Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

47 files changed, 30827 insertions, 0 deletions

diff --git a/fs/jfs/Kconfig b/fs/jfs/Kconfig
new file mode 100644
index 000000000..05cb0e8e4
--- /dev/null
+++ b/fs/jfs/Kconfig
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config JFS_FS
+	tristate "JFS filesystem support"
+	select NLS
+	select CRC32
+	help
+	  This is a port of IBM's Journaled Filesystem .  More information is
+	  available in the file <file:Documentation/admin-guide/jfs.rst>.
+
+	  If you do not intend to use the JFS filesystem, say N.
+
+config JFS_POSIX_ACL
+	bool "JFS POSIX Access Control Lists"
+	depends on JFS_FS
+	select FS_POSIX_ACL
+	help
+	  Posix Access Control Lists (ACLs) support permissions for users and
+	  groups beyond the owner/group/world scheme.
+
+	  If you don't know what Access Control Lists are, say N
+
+config JFS_SECURITY
+	bool "JFS Security Labels"
+	depends on JFS_FS
+	help
+	  Security labels support alternative access control models
+	  implemented by security modules like SELinux.  This option
+	  enables an extended attribute handler for file security
+	  labels in the jfs filesystem.
+
+	  If you are not using a security module that requires using
+	  extended attributes for file security labels, say N.
+
+config JFS_DEBUG
+	bool "JFS debugging"
+	depends on JFS_FS
+	help
+	  If you are experiencing any problems with the JFS filesystem, say
+	  Y here.  This will result in additional debugging messages to be
+	  written to the system log.  Under normal circumstances, this
+	  results in very little overhead.
+
+config JFS_STATISTICS
+	bool "JFS statistics"
+	depends on JFS_FS
+	help
+	  Enabling this option will cause statistics from the JFS file system
+	  to be made available to the user in the /proc/fs/jfs/ directory.
diff --git a/fs/jfs/Makefile b/fs/jfs/Makefile
new file mode 100644
index 000000000..7156d2c21
--- /dev/null
+++ b/fs/jfs/Makefile
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the Linux JFS filesystem routines.
+#
+
+obj-$(CONFIG_JFS_FS) += jfs.o
+
+jfs-y    := super.o file.o inode.o namei.o jfs_mount.o jfs_umount.o \
+	    jfs_xtree.o jfs_imap.o jfs_debug.o jfs_dmap.o \
+	    jfs_unicode.o jfs_dtree.o jfs_inode.o jfs_discard.o \
+	    jfs_extent.o symlink.o jfs_metapage.o \
+	    jfs_logmgr.o jfs_txnmgr.o jfs_uniupr.o \
+	    resize.o xattr.o ioctl.o
+
+jfs-$(CONFIG_JFS_POSIX_ACL) += acl.o
diff --git a/fs/jfs/acl.c b/fs/jfs/acl.c
new file mode 100644
index 000000000..a653f34c6
--- /dev/null
+++ b/fs/jfs/acl.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines  Corp., 2002-2004
+ *   Copyright (C) Andreas Gruenbacher, 2001
+ *   Copyright (C) Linus Torvalds, 1991, 1992
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/posix_acl_xattr.h>
+#include "jfs_incore.h"
+#include "jfs_txnmgr.h"
+#include "jfs_xattr.h"
+#include "jfs_acl.h"
+
+struct posix_acl *jfs_get_acl(struct inode *inode, int type, bool rcu)
+{
+	struct posix_acl *acl;
+	char *ea_name;
+	int size;
+	char *value = NULL;
+
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
+	switch(type) {
+		case ACL_TYPE_ACCESS:
+			ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
+			break;
+		case ACL_TYPE_DEFAULT:
+			ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
+			break;
+		default:
+			return ERR_PTR(-EINVAL);
+	}
+
+	size = __jfs_getxattr(inode, ea_name, NULL, 0);
+
+	if (size > 0) {
+		value = kmalloc(size, GFP_KERNEL);
+		if (!value)
+			return ERR_PTR(-ENOMEM);
+		size = __jfs_getxattr(inode, ea_name, value, size);
+	}
+
+	if (size < 0) {
+		if (size == -ENODATA)
+			acl = NULL;
+		else
+			acl = ERR_PTR(size);
+	} else {
+		acl = posix_acl_from_xattr(&init_user_ns, value, size);
+	}
+	kfree(value);
+	return acl;
+}
+
+static int __jfs_set_acl(tid_t tid, struct inode *inode, int type,
+		       struct posix_acl *acl)
+{
+	char *ea_name;
+	int rc;
+	int size = 0;
+	char *value = NULL;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (acl) {
+		size = posix_acl_xattr_size(acl->a_count);
+		value = kmalloc(size, GFP_KERNEL);
+		if (!value)
+			return -ENOMEM;
+		rc = posix_acl_to_xattr(&init_user_ns, acl, value, size);
+		if (rc < 0)
+			goto out;
+	}
+	rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0);
+out:
+	kfree(value);
+
+	if (!rc)
+		set_cached_acl(inode, type, acl);
+
+	return rc;
+}
+
+int jfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		struct posix_acl *acl, int type)
+{
+	int rc;
+	tid_t tid;
+	int update_mode = 0;
+	umode_t mode = inode->i_mode;
+
+	tid = txBegin(inode->i_sb, 0);
+	mutex_lock(&JFS_IP(inode)->commit_mutex);
+	if (type == ACL_TYPE_ACCESS && acl) {
+		rc = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
+		if (rc)
+			goto end_tx;
+		if (mode != inode->i_mode)
+			update_mode = 1;
+	}
+	rc = __jfs_set_acl(tid, inode, type, acl);
+	if (!rc) {
+		if (update_mode) {
+			inode->i_mode = mode;
+			inode->i_ctime = current_time(inode);
+			mark_inode_dirty(inode);
+		}
+		rc = txCommit(tid, 1, &inode, 0);
+	}
+end_tx:
+	txEnd(tid);
+	mutex_unlock(&JFS_IP(inode)->commit_mutex);
+	return rc;
+}
+
+int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
+{
+	struct posix_acl *default_acl, *acl;
+	int rc = 0;
+
+	rc = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
+	if (rc)
+		return rc;
+
+	if (default_acl) {
+		rc = __jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, default_acl);
+		posix_acl_release(default_acl);
+	} else {
+		inode->i_default_acl = NULL;
+	}
+
+	if (acl) {
+		if (!rc)
+			rc = __jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, acl);
+		posix_acl_release(acl);
+	} else {
+		inode->i_acl = NULL;
+	}
+
+	JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
+			       inode->i_mode;
+
+	return rc;
+}
diff --git a/fs/jfs/file.c b/fs/jfs/file.c
new file mode 100644
index 000000000..332dc9ac4
--- /dev/null
+++ b/fs/jfs/file.c
@@ -0,0 +1,153 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/posix_acl.h>
+#include <linux/quotaops.h>
+#include "jfs_incore.h"
+#include "jfs_inode.h"
+#include "jfs_dmap.h"
+#include "jfs_txnmgr.h"
+#include "jfs_xattr.h"
+#include "jfs_acl.h"
+#include "jfs_debug.h"
+
+int jfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+	struct inode *inode = file->f_mapping->host;
+	int rc = 0;
+
+	rc = file_write_and_wait_range(file, start, end);
+	if (rc)
+		return rc;
+
+	inode_lock(inode);
+	if (!(inode->i_state & I_DIRTY_ALL) ||
+	    (datasync && !(inode->i_state & I_DIRTY_DATASYNC))) {
+		/* Make sure committed changes hit the disk */
+		jfs_flush_journal(JFS_SBI(inode->i_sb)->log, 1);
+		inode_unlock(inode);
+		return rc;
+	}
+
+	rc |= jfs_commit_inode(inode, 1);
+	inode_unlock(inode);
+
+	return rc ? -EIO : 0;
+}
+
+static int jfs_open(struct inode *inode, struct file *file)
+{
+	int rc;
+
+	if ((rc = dquot_file_open(inode, file)))
+		return rc;
+
+	/*
+	 * We attempt to allow only one "active" file open per aggregate
+	 * group.  Otherwise, appending to files in parallel can cause
+	 * fragmentation within the files.
+	 *
+	 * If the file is empty, it was probably just created and going
+	 * to be written to.  If it has a size, we'll hold off until the
+	 * file is actually grown.
+	 */
+	if (S_ISREG(inode->i_mode) && file->f_mode & FMODE_WRITE &&
+	    (inode->i_size == 0)) {
+		struct jfs_inode_info *ji = JFS_IP(inode);
+		spin_lock_irq(&ji->ag_lock);
+		if (ji->active_ag == -1) {
+			struct jfs_sb_info *jfs_sb = JFS_SBI(inode->i_sb);
+			ji->active_ag = BLKTOAG(addressPXD(&ji->ixpxd), jfs_sb);
+			atomic_inc(&jfs_sb->bmap->db_active[ji->active_ag]);
+		}
+		spin_unlock_irq(&ji->ag_lock);
+	}
+
+	return 0;
+}
+static int jfs_release(struct inode *inode, struct file *file)
+{
+	struct jfs_inode_info *ji = JFS_IP(inode);
+
+	spin_lock_irq(&ji->ag_lock);
+	if (ji->active_ag != -1) {
+		struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
+		atomic_dec(&bmap->db_active[ji->active_ag]);
+		ji->active_ag = -1;
+	}
+	spin_unlock_irq(&ji->ag_lock);
+
+	return 0;
+}
+
+int jfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		struct iattr *iattr)
+{
+	struct inode *inode = d_inode(dentry);
+	int rc;
+
+	rc = setattr_prepare(&init_user_ns, dentry, iattr);
+	if (rc)
+		return rc;
+
+	if (is_quota_modification(mnt_userns, inode, iattr)) {
+		rc = dquot_initialize(inode);
+		if (rc)
+			return rc;
+	}
+	if ((iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)) ||
+	    (iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid))) {
+		rc = dquot_transfer(mnt_userns, inode, iattr);
+		if (rc)
+			return rc;
+	}
+
+	if ((iattr->ia_valid & ATTR_SIZE) &&
+	    iattr->ia_size != i_size_read(inode)) {
+		inode_dio_wait(inode);
+
+		rc = inode_newsize_ok(inode, iattr->ia_size);
+		if (rc)
+			return rc;
+
+		truncate_setsize(inode, iattr->ia_size);
+		jfs_truncate(inode);
+	}
+
+	setattr_copy(&init_user_ns, inode, iattr);
+	mark_inode_dirty(inode);
+
+	if (iattr->ia_valid & ATTR_MODE)
+		rc = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
+	return rc;
+}
+
+const struct inode_operations jfs_file_inode_operations = {
+	.listxattr	= jfs_listxattr,
+	.setattr	= jfs_setattr,
+	.fileattr_get	= jfs_fileattr_get,
+	.fileattr_set	= jfs_fileattr_set,
+#ifdef CONFIG_JFS_POSIX_ACL
+	.get_acl	= jfs_get_acl,
+	.set_acl	= jfs_set_acl,
+#endif
+};
+
+const struct file_operations jfs_file_operations = {
+	.open		= jfs_open,
+	.llseek		= generic_file_llseek,
+	.read_iter	= generic_file_read_iter,
+	.write_iter	= generic_file_write_iter,
+	.mmap		= generic_file_mmap,
+	.splice_read	= generic_file_splice_read,
+	.splice_write	= iter_file_splice_write,
+	.fsync		= jfs_fsync,
+	.release	= jfs_release,
+	.unlocked_ioctl = jfs_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+};
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
new file mode 100644
index 000000000..d1ec920aa
--- /dev/null
+++ b/fs/jfs/inode.c
@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+#include <linux/fs.h>
+#include <linux/mpage.h>
+#include <linux/buffer_head.h>
+#include <linux/pagemap.h>
+#include <linux/quotaops.h>
+#include <linux/uio.h>
+#include <linux/writeback.h>
+#include "jfs_incore.h"
+#include "jfs_inode.h"
+#include "jfs_filsys.h"
+#include "jfs_imap.h"
+#include "jfs_extent.h"
+#include "jfs_unicode.h"
+#include "jfs_debug.h"
+#include "jfs_dmap.h"
+
+
+struct inode *jfs_iget(struct super_block *sb, unsigned long ino)
+{
+	struct inode *inode;
+	int ret;
+
+	inode = iget_locked(sb, ino);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	ret = diRead(inode);
+	if (ret < 0) {
+		iget_failed(inode);
+		return ERR_PTR(ret);
+	}
+
+	if (S_ISREG(inode->i_mode)) {
+		inode->i_op = &jfs_file_inode_operations;
+		inode->i_fop = &jfs_file_operations;
+		inode->i_mapping->a_ops = &jfs_aops;
+	} else if (S_ISDIR(inode->i_mode)) {
+		inode->i_op = &jfs_dir_inode_operations;
+		inode->i_fop = &jfs_dir_operations;
+	} else if (S_ISLNK(inode->i_mode)) {
+		if (inode->i_size >= IDATASIZE) {
+			inode->i_op = &page_symlink_inode_operations;
+			inode_nohighmem(inode);
+			inode->i_mapping->a_ops = &jfs_aops;
+		} else {
+			inode->i_op = &jfs_fast_symlink_inode_operations;
+			inode->i_link = JFS_IP(inode)->i_inline;
+			/*
+			 * The inline data should be null-terminated, but
+			 * don't let on-disk corruption crash the kernel
+			 */
+			inode->i_link[inode->i_size] = '\0';
+		}
+	} else {
+		inode->i_op = &jfs_file_inode_operations;
+		init_special_inode(inode, inode->i_mode, inode->i_rdev);
+	}
+	unlock_new_inode(inode);
+	return inode;
+}
+
+/*
+ * Workhorse of both fsync & write_inode
+ */
+int jfs_commit_inode(struct inode *inode, int wait)
+{
+	int rc = 0;
+	tid_t tid;
+	static int noisy = 5;
+
+	jfs_info("In jfs_commit_inode, inode = 0x%p", inode);
+
+	/*
+	 * Don't commit if inode has been committed since last being
+	 * marked dirty, or if it has been deleted.
+	 */
+	if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))
+		return 0;
+
+	if (isReadOnly(inode)) {
+		/* kernel allows writes to devices on read-only
+		 * partitions and may think inode is dirty
+		 */
+		if (!special_file(inode->i_mode) && noisy) {
+			jfs_err("jfs_commit_inode(0x%p) called on read-only volume",
+				inode);
+			jfs_err("Is remount racy?");
+			noisy--;
+		}
+		return 0;
+	}
+
+	tid = txBegin(inode->i_sb, COMMIT_INODE);
+	mutex_lock(&JFS_IP(inode)->commit_mutex);
+
+	/*
+	 * Retest inode state after taking commit_mutex
+	 */
+	if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))
+		rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);
+
+	txEnd(tid);
+	mutex_unlock(&JFS_IP(inode)->commit_mutex);
+	return rc;
+}
+
+int jfs_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+	int wait = wbc->sync_mode == WB_SYNC_ALL;
+
+	if (inode->i_nlink == 0)
+		return 0;
+	/*
+	 * If COMMIT_DIRTY is not set, the inode isn't really dirty.
+	 * It has been committed since the last change, but was still
+	 * on the dirty inode list.
+	 */
+	if (!test_cflag(COMMIT_Dirty, inode)) {
+		/* Make sure committed changes hit the disk */
+		jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
+		return 0;
+	}
+
+	if (jfs_commit_inode(inode, wait)) {
+		jfs_err("jfs_write_inode: jfs_commit_inode failed!");
+		return -EIO;
+	} else
+		return 0;
+}
+
+void jfs_evict_inode(struct inode *inode)
+{
+	struct jfs_inode_info *ji = JFS_IP(inode);
+
+	jfs_info("In jfs_evict_inode, inode = 0x%p", inode);
+
+	if (!inode->i_nlink && !is_bad_inode(inode)) {
+		dquot_initialize(inode);
+
+		if (JFS_IP(inode)->fileset == FILESYSTEM_I) {
+			struct inode *ipimap = JFS_SBI(inode->i_sb)->ipimap;
+			truncate_inode_pages_final(&inode->i_data);
+
+			if (test_cflag(COMMIT_Freewmap, inode))
+				jfs_free_zero_link(inode);
+
+			if (ipimap && JFS_IP(ipimap)->i_imap)
+				diFree(inode);
+
+			/*
+			 * Free the inode from the quota allocation.
+			 */
+			dquot_free_inode(inode);
+		}
+	} else {
+		truncate_inode_pages_final(&inode->i_data);
+	}
+	clear_inode(inode);
+	dquot_drop(inode);
+
+	BUG_ON(!list_empty(&ji->anon_inode_list));
+
+	spin_lock_irq(&ji->ag_lock);
+	if (ji->active_ag != -1) {
+		struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
+		atomic_dec(&bmap->db_active[ji->active_ag]);
+		ji->active_ag = -1;
+	}
+	spin_unlock_irq(&ji->ag_lock);
+}
+
+void jfs_dirty_inode(struct inode *inode, int flags)
+{
+	static int noisy = 5;
+
+	if (isReadOnly(inode)) {
+		if (!special_file(inode->i_mode) && noisy) {
+			/* kernel allows writes to devices on read-only
+			 * partitions and may try to mark inode dirty
+			 */
+			jfs_err("jfs_dirty_inode called on read-only volume");
+			jfs_err("Is remount racy?");
+			noisy--;
+		}
+		return;
+	}
+
+	set_cflag(COMMIT_Dirty, inode);
+}
+
+int jfs_get_block(struct inode *ip, sector_t lblock,
+		  struct buffer_head *bh_result, int create)
+{
+	s64 lblock64 = lblock;
+	int rc = 0;
+	xad_t xad;
+	s64 xaddr;
+	int xflag;
+	s32 xlen = bh_result->b_size >> ip->i_blkbits;
+
+	/*
+	 * Take appropriate lock on inode
+	 */
+	if (create)
+		IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
+	else
+		IREAD_LOCK(ip, RDWRLOCK_NORMAL);
+
+	if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&
+	    (!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) &&
+	    xaddr) {
+		if (xflag & XAD_NOTRECORDED) {
+			if (!create)
+				/*
+				 * Allocated but not recorded, read treats
+				 * this as a hole
+				 */
+				goto unlock;
+			XADoffset(&xad, lblock64);
+			XADlength(&xad, xlen);
+			XADaddress(&xad, xaddr);
+			rc = extRecord(ip, &xad);
+			if (rc)
+				goto unlock;
+			set_buffer_new(bh_result);
+		}
+
+		map_bh(bh_result, ip->i_sb, xaddr);
+		bh_result->b_size = xlen << ip->i_blkbits;
+		goto unlock;
+	}
+	if (!create)
+		goto unlock;
+
+	/*
+	 * Allocate a new block
+	 */
+	if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
+		goto unlock;
+	rc = extAlloc(ip, xlen, lblock64, &xad, false);
+	if (rc)
+		goto unlock;
+
+	set_buffer_new(bh_result);
+	map_bh(bh_result, ip->i_sb, addressXAD(&xad));
+	bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;
+
+      unlock:
+	/*
+	 * Release lock on inode
+	 */
+	if (create)
+		IWRITE_UNLOCK(ip);
+	else
+		IREAD_UNLOCK(ip);
+	return rc;
+}
+
+static int jfs_writepage(struct page *page, struct writeback_control *wbc)
+{
+	return block_write_full_page(page, jfs_get_block, wbc);
+}
+
+static int jfs_writepages(struct address_space *mapping,
+			struct writeback_control *wbc)
+{
+	return mpage_writepages(mapping, wbc, jfs_get_block);
+}
+
+static int jfs_read_folio(struct file *file, struct folio *folio)
+{
+	return mpage_read_folio(folio, jfs_get_block);
+}
+
+static void jfs_readahead(struct readahead_control *rac)
+{
+	mpage_readahead(rac, jfs_get_block);
+}
+
+static void jfs_write_failed(struct address_space *mapping, loff_t to)
+{
+	struct inode *inode = mapping->host;
+
+	if (to > inode->i_size) {
+		truncate_pagecache(inode, inode->i_size);
+		jfs_truncate(inode);
+	}
+}
+
+static int jfs_write_begin(struct file *file, struct address_space *mapping,
+				loff_t pos, unsigned len,
+				struct page **pagep, void **fsdata)
+{
+	int ret;
+
+	ret = block_write_begin(mapping, pos, len, pagep, jfs_get_block);
+	if (unlikely(ret))
+		jfs_write_failed(mapping, pos + len);
+
+	return ret;
+}
+
+static int jfs_write_end(struct file *file, struct address_space *mapping,
+		loff_t pos, unsigned len, unsigned copied, struct page *page,
+		void *fsdata)
+{
+	int ret;
+
+	ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
+	if (ret < len)
+		jfs_write_failed(mapping, pos + len);
+	return ret;
+}
+
+static sector_t jfs_bmap(struct address_space *mapping, sector_t block)
+{
+	return generic_block_bmap(mapping, block, jfs_get_block);
+}
+
+static ssize_t jfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
+{
+	struct file *file = iocb->ki_filp;
+	struct address_space *mapping = file->f_mapping;
+	struct inode *inode = file->f_mapping->host;
+	size_t count = iov_iter_count(iter);
+	ssize_t ret;
+
+	ret = blockdev_direct_IO(iocb, inode, iter, jfs_get_block);
+
+	/*
+	 * In case of error extending write may have instantiated a few
+	 * blocks outside i_size. Trim these off again.
+	 */
+	if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) {
+		loff_t isize = i_size_read(inode);
+		loff_t end = iocb->ki_pos + count;
+
+		if (end > isize)
+			jfs_write_failed(mapping, end);
+	}
+
+	return ret;
+}
+
+const struct address_space_operations jfs_aops = {
+	.dirty_folio	= block_dirty_folio,
+	.invalidate_folio = block_invalidate_folio,
+	.read_folio	= jfs_read_folio,
+	.readahead	= jfs_readahead,
+	.writepage	= jfs_writepage,
+	.writepages	= jfs_writepages,
+	.write_begin	= jfs_write_begin,
+	.write_end	= jfs_write_end,
+	.bmap		= jfs_bmap,
+	.direct_IO	= jfs_direct_IO,
+};
+
+/*
+ * Guts of jfs_truncate.  Called with locks already held.  Can be called
+ * with directory for truncating directory index table.
+ */
+void jfs_truncate_nolock(struct inode *ip, loff_t length)
+{
+	loff_t newsize;
+	tid_t tid;
+
+	ASSERT(length >= 0);
+
+	if (test_cflag(COMMIT_Nolink, ip)) {
+		xtTruncate(0, ip, length, COMMIT_WMAP);
+		return;
+	}
+
+	do {
+		tid = txBegin(ip->i_sb, 0);
+
+		/*
+		 * The commit_mutex cannot be taken before txBegin.
+		 * txBegin may block and there is a chance the inode
+		 * could be marked dirty and need to be committed
+		 * before txBegin unblocks
+		 */
+		mutex_lock(&JFS_IP(ip)->commit_mutex);
+
+		newsize = xtTruncate(tid, ip, length,
+				     COMMIT_TRUNCATE | COMMIT_PWMAP);
+		if (newsize < 0) {
+			txEnd(tid);
+			mutex_unlock(&JFS_IP(ip)->commit_mutex);
+			break;
+		}
+
+		ip->i_mtime = ip->i_ctime = current_time(ip);
+		mark_inode_dirty(ip);
+
+		txCommit(tid, 1, &ip, 0);
+		txEnd(tid);
+		mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	} while (newsize > length);	/* Truncate isn't always atomic */
+}
+
+void jfs_truncate(struct inode *ip)
+{
+	jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);
+
+	block_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);
+
+	IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
+	jfs_truncate_nolock(ip, ip->i_size);
+	IWRITE_UNLOCK(ip);
+}
diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c
new file mode 100644
index 000000000..1e7b177ec
--- /dev/null
+++ b/fs/jfs/ioctl.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/jfs/ioctl.c
+ *
+ * Copyright (C) 2006 Herbert Poetzl
+ * adapted from Remy Card's ext2/ioctl.c
+ */
+
+#include <linux/fs.h>
+#include <linux/ctype.h>
+#include <linux/capability.h>
+#include <linux/mount.h>
+#include <linux/time.h>
+#include <linux/sched.h>
+#include <linux/blkdev.h>
+#include <asm/current.h>
+#include <linux/uaccess.h>
+#include <linux/fileattr.h>
+
+#include "jfs_filsys.h"
+#include "jfs_debug.h"
+#include "jfs_incore.h"
+#include "jfs_dinode.h"
+#include "jfs_inode.h"
+#include "jfs_dmap.h"
+#include "jfs_discard.h"
+
+static struct {
+	long jfs_flag;
+	long ext2_flag;
+} jfs_map[] = {
+	{JFS_NOATIME_FL,	FS_NOATIME_FL},
+	{JFS_DIRSYNC_FL,	FS_DIRSYNC_FL},
+	{JFS_SYNC_FL,		FS_SYNC_FL},
+	{JFS_SECRM_FL,		FS_SECRM_FL},
+	{JFS_UNRM_FL,		FS_UNRM_FL},
+	{JFS_APPEND_FL,		FS_APPEND_FL},
+	{JFS_IMMUTABLE_FL,	FS_IMMUTABLE_FL},
+	{0, 0},
+};
+
+static long jfs_map_ext2(unsigned long flags, int from)
+{
+	int index=0;
+	long mapped=0;
+
+	while (jfs_map[index].jfs_flag) {
+		if (from) {
+			if (jfs_map[index].ext2_flag & flags)
+				mapped |= jfs_map[index].jfs_flag;
+		} else {
+			if (jfs_map[index].jfs_flag & flags)
+				mapped |= jfs_map[index].ext2_flag;
+		}
+		index++;
+	}
+	return mapped;
+}
+
+int jfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
+{
+	struct jfs_inode_info *jfs_inode = JFS_IP(d_inode(dentry));
+	unsigned int flags = jfs_inode->mode2 & JFS_FL_USER_VISIBLE;
+
+	if (d_is_special(dentry))
+		return -ENOTTY;
+
+	fileattr_fill_flags(fa, jfs_map_ext2(flags, 0));
+
+	return 0;
+}
+
+int jfs_fileattr_set(struct user_namespace *mnt_userns,
+		     struct dentry *dentry, struct fileattr *fa)
+{
+	struct inode *inode = d_inode(dentry);
+	struct jfs_inode_info *jfs_inode = JFS_IP(inode);
+	unsigned int flags;
+
+	if (d_is_special(dentry))
+		return -ENOTTY;
+
+	if (fileattr_has_fsx(fa))
+		return -EOPNOTSUPP;
+
+	flags = jfs_map_ext2(fa->flags, 1);
+	if (!S_ISDIR(inode->i_mode))
+		flags &= ~JFS_DIRSYNC_FL;
+
+	/* Is it quota file? Do not allow user to mess with it */
+	if (IS_NOQUOTA(inode))
+		return -EPERM;
+
+	flags = flags & JFS_FL_USER_MODIFIABLE;
+	flags |= jfs_inode->mode2 & ~JFS_FL_USER_MODIFIABLE;
+	jfs_inode->mode2 = flags;
+
+	jfs_set_inode_flags(inode);
+	inode->i_ctime = current_time(inode);
+	mark_inode_dirty(inode);
+
+	return 0;
+}
+
+long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	struct inode *inode = file_inode(filp);
+
+	switch (cmd) {
+	case FITRIM:
+	{
+		struct super_block *sb = inode->i_sb;
+		struct fstrim_range range;
+		s64 ret = 0;
+
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+
+		if (!bdev_max_discard_sectors(sb->s_bdev)) {
+			jfs_warn("FITRIM not supported on device");
+			return -EOPNOTSUPP;
+		}
+
+		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
+		    sizeof(range)))
+			return -EFAULT;
+
+		range.minlen = max_t(unsigned int, range.minlen,
+				     bdev_discard_granularity(sb->s_bdev));
+
+		ret = jfs_ioc_trim(inode, &range);
+		if (ret < 0)
+			return ret;
+
+		if (copy_to_user((struct fstrim_range __user *)arg, &range,
+		    sizeof(range)))
+			return -EFAULT;
+
+		return 0;
+	}
+
+	default:
+		return -ENOTTY;
+	}
+}
diff --git a/fs/jfs/jfs_acl.h b/fs/jfs/jfs_acl.h
new file mode 100644
index 000000000..3de40286d
--- /dev/null
+++ b/fs/jfs/jfs_acl.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines  Corp., 2002
+ */
+#ifndef _H_JFS_ACL
+#define _H_JFS_ACL
+
+#ifdef CONFIG_JFS_POSIX_ACL
+
+struct posix_acl *jfs_get_acl(struct inode *inode, int type, bool rcu);
+int jfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		struct posix_acl *acl, int type);
+int jfs_init_acl(tid_t, struct inode *, struct inode *);
+
+#else
+
+static inline int jfs_init_acl(tid_t tid, struct inode *inode,
+			       struct inode *dir)
+{
+	return 0;
+}
+
+#endif
+#endif		/* _H_JFS_ACL */
diff --git a/fs/jfs/jfs_btree.h b/fs/jfs/jfs_btree.h
new file mode 100644
index 000000000..ce055ef50
--- /dev/null
+++ b/fs/jfs/jfs_btree.h
@@ -0,0 +1,159 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+#ifndef	_H_JFS_BTREE
+#define _H_JFS_BTREE
+
+/*
+ *	jfs_btree.h: B+-tree
+ *
+ * JFS B+-tree (dtree and xtree) common definitions
+ */
+
+/*
+ *	basic btree page - btpage
+ *
+struct btpage {
+	s64 next;		right sibling bn
+	s64 prev;		left sibling bn
+
+	u8 flag;
+	u8 rsrvd[7];		type specific
+	s64 self;		self address
+
+	u8 entry[4064];
+};						*/
+
+/* btpaget_t flag */
+#define BT_TYPE		0x07	/* B+-tree index */
+#define	BT_ROOT		0x01	/* root page */
+#define	BT_LEAF		0x02	/* leaf page */
+#define	BT_INTERNAL	0x04	/* internal page */
+#define	BT_RIGHTMOST	0x10	/* rightmost page */
+#define	BT_LEFTMOST	0x20	/* leftmost page */
+#define	BT_SWAPPED	0x80	/* used by fsck for endian swapping */
+
+/* btorder (in inode) */
+#define	BT_RANDOM		0x0000
+#define	BT_SEQUENTIAL		0x0001
+#define	BT_LOOKUP		0x0010
+#define	BT_INSERT		0x0020
+#define	BT_DELETE		0x0040
+
+/*
+ *	btree page buffer cache access
+ */
+#define BT_IS_ROOT(MP) (((MP)->xflag & COMMIT_PAGE) == 0)
+
+/* get page from buffer page */
+#define BT_PAGE(IP, MP, TYPE, ROOT)\
+	(BT_IS_ROOT(MP) ? (TYPE *)&JFS_IP(IP)->ROOT : (TYPE *)(MP)->data)
+
+/* get the page buffer and the page for specified block address */
+#define BT_GETPAGE(IP, BN, MP, TYPE, SIZE, P, RC, ROOT)\
+{\
+	if ((BN) == 0)\
+	{\
+		MP = (struct metapage *)&JFS_IP(IP)->bxflag;\
+		P = (TYPE *)&JFS_IP(IP)->ROOT;\
+		RC = 0;\
+	}\
+	else\
+	{\
+		MP = read_metapage((IP), BN, SIZE, 1);\
+		if (MP) {\
+			RC = 0;\
+			P = (MP)->data;\
+		} else {\
+			P = NULL;\
+			jfs_err("bread failed!");\
+			RC = -EIO;\
+		}\
+	}\
+}
+
+#define BT_MARK_DIRTY(MP, IP)\
+{\
+	if (BT_IS_ROOT(MP))\
+		mark_inode_dirty(IP);\
+	else\
+		mark_metapage_dirty(MP);\
+}
+
+/* put the page buffer */
+#define BT_PUTPAGE(MP)\
+{\
+	if (! BT_IS_ROOT(MP)) \
+		release_metapage(MP); \
+}
+
+
+/*
+ *	btree traversal stack
+ *
+ * record the path traversed during the search;
+ * top frame record the leaf page/entry selected.
+ */
+struct btframe {	/* stack frame */
+	s64 bn;			/* 8: */
+	s16 index;		/* 2: */
+	s16 lastindex;		/* 2: unused */
+	struct metapage *mp;	/* 4/8: */
+};				/* (16/24) */
+
+struct btstack {
+	struct btframe *top;
+	int nsplit;
+	struct btframe stack[MAXTREEHEIGHT];
+};
+
+#define BT_CLR(btstack)\
+	(btstack)->top = (btstack)->stack
+
+#define BT_STACK_FULL(btstack)\
+	( (btstack)->top == &((btstack)->stack[MAXTREEHEIGHT-1]))
+
+#define BT_PUSH(BTSTACK, BN, INDEX)\
+{\
+	assert(!BT_STACK_FULL(BTSTACK));\
+	(BTSTACK)->top->bn = BN;\
+	(BTSTACK)->top->index = INDEX;\
+	++(BTSTACK)->top;\
+}
+
+#define BT_POP(btstack)\
+	( (btstack)->top == (btstack)->stack ? NULL : --(btstack)->top )
+
+#define BT_STACK(btstack)\
+	( (btstack)->top == (btstack)->stack ? NULL : (btstack)->top )
+
+static inline void BT_STACK_DUMP(struct btstack *btstack)
+{
+	int i;
+	printk("btstack dump:\n");
+	for (i = 0; i < MAXTREEHEIGHT; i++)
+		printk(KERN_ERR "bn = %Lx, index = %d\n",
+		       (long long)btstack->stack[i].bn,
+		       btstack->stack[i].index);
+}
+
+/* retrieve search results */
+#define BT_GETSEARCH(IP, LEAF, BN, MP, TYPE, P, INDEX, ROOT)\
+{\
+	BN = (LEAF)->bn;\
+	MP = (LEAF)->mp;\
+	if (BN)\
+		P = (TYPE *)MP->data;\
+	else\
+		P = (TYPE *)&JFS_IP(IP)->ROOT;\
+	INDEX = (LEAF)->index;\
+}
+
+/* put the page buffer of search */
+#define BT_PUTSEARCH(BTSTACK)\
+{\
+	if (! BT_IS_ROOT((BTSTACK)->top->mp))\
+		release_metapage((BTSTACK)->top->mp);\
+}
+#endif				/* _H_JFS_BTREE */
diff --git a/fs/jfs/jfs_debug.c b/fs/jfs/jfs_debug.c
new file mode 100644
index 000000000..44b62b3c3
--- /dev/null
+++ b/fs/jfs/jfs_debug.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+#include <linux/fs.h>
+#include <linux/ctype.h>
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/uaccess.h>
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_debug.h"
+
+#ifdef PROC_FS_JFS /* see jfs_debug.h */
+
+#ifdef CONFIG_JFS_DEBUG
+static int jfs_loglevel_proc_show(struct seq_file *m, void *v)
+{
+	seq_printf(m, "%d\n", jfsloglevel);
+	return 0;
+}
+
+static int jfs_loglevel_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, jfs_loglevel_proc_show, NULL);
+}
+
+static ssize_t jfs_loglevel_proc_write(struct file *file,
+		const char __user *buffer, size_t count, loff_t *ppos)
+{
+	char c;
+
+	if (get_user(c, buffer))
+		return -EFAULT;
+
+	/* yes, I know this is an ASCIIism.  --hch */
+	if (c < '0' || c > '9')
+		return -EINVAL;
+	jfsloglevel = c - '0';
+	return count;
+}
+
+static const struct proc_ops jfs_loglevel_proc_ops = {
+	.proc_open	= jfs_loglevel_proc_open,
+	.proc_read	= seq_read,
+	.proc_lseek	= seq_lseek,
+	.proc_release	= single_release,
+	.proc_write	= jfs_loglevel_proc_write,
+};
+#endif
+
+void jfs_proc_init(void)
+{
+	struct proc_dir_entry *base;
+
+	base = proc_mkdir("fs/jfs", NULL);
+	if (!base)
+		return;
+
+#ifdef CONFIG_JFS_STATISTICS
+	proc_create_single("lmstats", 0, base, jfs_lmstats_proc_show);
+	proc_create_single("txstats", 0, base, jfs_txstats_proc_show);
+	proc_create_single("xtstat", 0, base, jfs_xtstat_proc_show);
+	proc_create_single("mpstat", 0, base, jfs_mpstat_proc_show);
+#endif
+#ifdef CONFIG_JFS_DEBUG
+	proc_create_single("TxAnchor", 0, base, jfs_txanchor_proc_show);
+	proc_create("loglevel", 0, base, &jfs_loglevel_proc_ops);
+#endif
+}
+
+void jfs_proc_clean(void)
+{
+	remove_proc_subtree("fs/jfs", NULL);
+}
+
+#endif /* PROC_FS_JFS */
diff --git a/fs/jfs/jfs_debug.h b/fs/jfs/jfs_debug.h
new file mode 100644
index 000000000..48e2150c0
--- /dev/null
+++ b/fs/jfs/jfs_debug.h
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+#ifndef _H_JFS_DEBUG
+#define _H_JFS_DEBUG
+
+/*
+ *	jfs_debug.h
+ *
+ * global debug message, data structure/macro definitions
+ * under control of CONFIG_JFS_DEBUG, CONFIG_JFS_STATISTICS;
+ */
+
+/*
+ * Create /proc/fs/jfs if procfs is enabled andeither
+ * CONFIG_JFS_DEBUG or CONFIG_JFS_STATISTICS is defined
+ */
+#if defined(CONFIG_PROC_FS) && (defined(CONFIG_JFS_DEBUG) || defined(CONFIG_JFS_STATISTICS))
+#define PROC_FS_JFS
+extern void jfs_proc_init(void);
+extern void jfs_proc_clean(void);
+#endif
+
+/*
+ *	assert with traditional printf/panic
+ */
+#define assert(p) do {	\
+	if (!(p)) {	\
+		printk(KERN_CRIT "BUG at %s:%d assert(%s)\n",	\
+		       __FILE__, __LINE__, #p);			\
+		BUG();	\
+	}		\
+} while (0)
+
+/*
+ *	debug ON
+ *	--------
+ */
+#ifdef CONFIG_JFS_DEBUG
+#define ASSERT(p) assert(p)
+
+/* printk verbosity */
+#define JFS_LOGLEVEL_ERR 1
+#define JFS_LOGLEVEL_WARN 2
+#define JFS_LOGLEVEL_DEBUG 3
+#define JFS_LOGLEVEL_INFO 4
+
+extern int jfsloglevel;
+
+int jfs_txanchor_proc_show(struct seq_file *m, void *v);
+
+/* information message: e.g., configuration, major event */
+#define jfs_info(fmt, arg...) do {			\
+	if (jfsloglevel >= JFS_LOGLEVEL_INFO)		\
+		printk(KERN_INFO fmt "\n", ## arg);	\
+} while (0)
+
+/* debug message: ad hoc */
+#define jfs_debug(fmt, arg...) do {			\
+	if (jfsloglevel >= JFS_LOGLEVEL_DEBUG)		\
+		printk(KERN_DEBUG fmt "\n", ## arg);	\
+} while (0)
+
+/* warn message: */
+#define jfs_warn(fmt, arg...) do {			\
+	if (jfsloglevel >= JFS_LOGLEVEL_WARN)		\
+		printk(KERN_WARNING fmt "\n", ## arg);	\
+} while (0)
+
+/* error event message: e.g., i/o error */
+#define jfs_err(fmt, arg...) do {			\
+	if (jfsloglevel >= JFS_LOGLEVEL_ERR)		\
+		printk(KERN_ERR fmt "\n", ## arg);	\
+} while (0)
+
+/*
+ *	debug OFF
+ *	---------
+ */
+#else				/* CONFIG_JFS_DEBUG */
+#define ASSERT(p) do {} while (0)
+#define jfs_info(fmt, arg...) do {} while (0)
+#define jfs_debug(fmt, arg...) do {} while (0)
+#define jfs_warn(fmt, arg...) do {} while (0)
+#define jfs_err(fmt, arg...) do {} while (0)
+#endif				/* CONFIG_JFS_DEBUG */
+
+/*
+ *	statistics
+ *	----------
+ */
+#ifdef	CONFIG_JFS_STATISTICS
+int jfs_lmstats_proc_show(struct seq_file *m, void *v);
+int jfs_txstats_proc_show(struct seq_file *m, void *v);
+int jfs_mpstat_proc_show(struct seq_file *m, void *v);
+int jfs_xtstat_proc_show(struct seq_file *m, void *v);
+
+#define	INCREMENT(x)		((x)++)
+#define	DECREMENT(x)		((x)--)
+#define	HIGHWATERMARK(x,y)	((x) = max((x), (y)))
+#else
+#define	INCREMENT(x)
+#define	DECREMENT(x)
+#define	HIGHWATERMARK(x,y)
+#endif				/* CONFIG_JFS_STATISTICS */
+
+#endif				/* _H_JFS_DEBUG */
diff --git a/fs/jfs/jfs_dinode.h b/fs/jfs/jfs_dinode.h
new file mode 100644
index 000000000..6b231d0d0
--- /dev/null
+++ b/fs/jfs/jfs_dinode.h
@@ -0,0 +1,169 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2001
+ */
+#ifndef _H_JFS_DINODE
+#define _H_JFS_DINODE
+
+/*
+ *	jfs_dinode.h: on-disk inode manager
+ */
+
+#define INODESLOTSIZE		128
+#define L2INODESLOTSIZE		7
+#define log2INODESIZE		9	/* log2(bytes per dinode) */
+
+
+/*
+ *	on-disk inode : 512 bytes
+ *
+ * note: align 64-bit fields on 8-byte boundary.
+ */
+struct dinode {
+	/*
+	 *	I. base area (128 bytes)
+	 *	------------------------
+	 *
+	 * define generic/POSIX attributes
+	 */
+	__le32 di_inostamp;	/* 4: stamp to show inode belongs to fileset */
+	__le32 di_fileset;	/* 4: fileset number */
+	__le32 di_number;	/* 4: inode number, aka file serial number */
+	__le32 di_gen;		/* 4: inode generation number */
+
+	pxd_t di_ixpxd;		/* 8: inode extent descriptor */
+
+	__le64 di_size;		/* 8: size */
+	__le64 di_nblocks;	/* 8: number of blocks allocated */
+
+	__le32 di_nlink;	/* 4: number of links to the object */
+
+	__le32 di_uid;		/* 4: user id of owner */
+	__le32 di_gid;		/* 4: group id of owner */
+
+	__le32 di_mode;		/* 4: attribute, format and permission */
+
+	struct timestruc_t di_atime;	/* 8: time last data accessed */
+	struct timestruc_t di_ctime;	/* 8: time last status changed */
+	struct timestruc_t di_mtime;	/* 8: time last data modified */
+	struct timestruc_t di_otime;	/* 8: time created */
+
+	dxd_t di_acl;		/* 16: acl descriptor */
+
+	dxd_t di_ea;		/* 16: ea descriptor */
+
+	__le32 di_next_index;	/* 4: Next available dir_table index */
+
+	__le32 di_acltype;	/* 4: Type of ACL */
+
+	/*
+	 *	Extension Areas.
+	 *
+	 *	Historically, the inode was partitioned into 4 128-byte areas,
+	 *	the last 3 being defined as unions which could have multiple
+	 *	uses.  The first 96 bytes had been completely unused until
+	 *	an index table was added to the directory.  It is now more
+	 *	useful to describe the last 3/4 of the inode as a single
+	 *	union.  We would probably be better off redesigning the
+	 *	entire structure from scratch, but we don't want to break
+	 *	commonality with OS/2's JFS at this time.
+	 */
+	union {
+		struct {
+			/*
+			 * This table contains the information needed to
+			 * find a directory entry from a 32-bit index.
+			 * If the index is small enough, the table is inline,
+			 * otherwise, an x-tree root overlays this table
+			 */
+			struct dir_table_slot _table[12]; /* 96: inline */
+
+			dtroot_t _dtroot;		/* 288: dtree root */
+		} _dir;					/* (384) */
+#define di_dirtable	u._dir._table
+#define di_dtroot	u._dir._dtroot
+#define di_parent	di_dtroot.header.idotdot
+#define di_DASD		di_dtroot.header.DASD
+
+		struct {
+			union {
+				u8 _data[96];		/* 96: unused */
+				struct {
+					void *_imap;	/* 4: unused */
+					__le32 _gengen;	/* 4: generator */
+				} _imap;
+			} _u1;				/* 96: */
+#define di_gengen	u._file._u1._imap._gengen
+
+			union {
+				xtpage_t _xtroot;
+				struct {
+					u8 unused[16];	/* 16: */
+					dxd_t _dxd;	/* 16: */
+					union {
+						/*
+						 * The fast symlink area
+						 * is expected to overflow
+						 * into _inlineea when
+						 * needed (which will clear
+						 * INLINEEA).
+						 */
+						struct {
+							union {
+								__le32 _rdev;	/* 4: */
+								u8 _fastsymlink[128];
+							} _u;
+							u8 _inlineea[128];
+						};
+						u8 _inline_all[256];
+					};
+				} _special;
+			} _u2;
+		} _file;
+#define di_xtroot	u._file._u2._xtroot
+#define di_dxd		u._file._u2._special._dxd
+#define di_btroot	di_xtroot
+#define di_inlinedata	u._file._u2._special._u
+#define di_rdev		u._file._u2._special._u._rdev
+#define di_fastsymlink	u._file._u2._special._u._fastsymlink
+#define di_inlineea	u._file._u2._special._inlineea
+#define di_inline_all	u._file._u2._special._inline_all
+	} u;
+};
+
+/* extended mode bits (on-disk inode di_mode) */
+#define IFJOURNAL	0x00010000	/* journalled file */
+#define ISPARSE		0x00020000	/* sparse file enabled */
+#define INLINEEA	0x00040000	/* inline EA area free */
+#define ISWAPFILE	0x00800000	/* file open for pager swap space */
+
+/* more extended mode bits: attributes for OS/2 */
+#define IREADONLY	0x02000000	/* no write access to file */
+#define IHIDDEN		0x04000000	/* hidden file */
+#define ISYSTEM		0x08000000	/* system file */
+
+#define IDIRECTORY	0x20000000	/* directory (shadow of real bit) */
+#define IARCHIVE	0x40000000	/* file archive bit */
+#define INEWNAME	0x80000000	/* non-8.3 filename format */
+
+#define IRASH		0x4E000000	/* mask for changeable attributes */
+#define ATTRSHIFT	25	/* bits to shift to move attribute
+				   specification to mode position */
+
+/* extended attributes for Linux */
+
+#define JFS_NOATIME_FL		0x00080000 /* do not update atime */
+
+#define JFS_DIRSYNC_FL		0x00100000 /* dirsync behaviour */
+#define JFS_SYNC_FL		0x00200000 /* Synchronous updates */
+#define JFS_SECRM_FL		0x00400000 /* Secure deletion */
+#define JFS_UNRM_FL		0x00800000 /* allow for undelete */
+
+#define JFS_APPEND_FL		0x01000000 /* writes to file may only append */
+#define JFS_IMMUTABLE_FL	0x02000000 /* Immutable file */
+
+#define JFS_FL_USER_VISIBLE	0x03F80000
+#define JFS_FL_USER_MODIFIABLE	0x03F80000
+#define JFS_FL_INHERIT		0x03C80000
+
+#endif /*_H_JFS_DINODE */
diff --git a/fs/jfs/jfs_discard.c b/fs/jfs/jfs_discard.c
new file mode 100644
index 000000000..575cb2ba7
--- /dev/null
+++ b/fs/jfs/jfs_discard.c
@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) Tino Reichardt, 2012
+ */
+
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_discard.h"
+#include "jfs_dmap.h"
+#include "jfs_debug.h"
+
+
+/*
+ * NAME:	jfs_issue_discard()
+ *
+ * FUNCTION:	TRIM the specified block range on device, if supported
+ *
+ * PARAMETERS:
+ *	ip	- pointer to in-core inode
+ *	blkno	- starting block number to be trimmed (0..N)
+ *	nblocks	- number of blocks to be trimmed
+ *
+ * RETURN VALUES:
+ *	none
+ *
+ * serialization: IREAD_LOCK(ipbmap) held on entry/exit;
+ */
+void jfs_issue_discard(struct inode *ip, u64 blkno, u64 nblocks)
+{
+	struct super_block *sb = ip->i_sb;
+	int r = 0;
+
+	r = sb_issue_discard(sb, blkno, nblocks, GFP_NOFS, 0);
+	if (unlikely(r != 0)) {
+		jfs_err("JFS: sb_issue_discard(%p, %llu, %llu, GFP_NOFS, 0) = %d => failed!",
+			sb, (unsigned long long)blkno,
+			(unsigned long long)nblocks, r);
+	}
+
+	jfs_info("JFS: sb_issue_discard(%p, %llu, %llu, GFP_NOFS, 0) = %d",
+		sb, (unsigned long long)blkno,
+		(unsigned long long)nblocks, r);
+
+	return;
+}
+
+/*
+ * NAME:	jfs_ioc_trim()
+ *
+ * FUNCTION:	attempt to discard (TRIM) all free blocks from the
+ *              filesystem.
+ *
+ * PARAMETERS:
+ *	ip	- pointer to in-core inode;
+ *	range	- the range, given by user space
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error
+ */
+int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
+{
+	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
+	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
+	struct super_block *sb = ipbmap->i_sb;
+	int agno, agno_end;
+	u64 start, end, minlen;
+	u64 trimmed = 0;
+
+	/**
+	 * convert byte values to block size of filesystem:
+	 * start:	First Byte to trim
+	 * len:		number of Bytes to trim from start
+	 * minlen:	minimum extent length in Bytes
+	 */
+	start = range->start >> sb->s_blocksize_bits;
+	end = start + (range->len >> sb->s_blocksize_bits) - 1;
+	minlen = range->minlen >> sb->s_blocksize_bits;
+	if (minlen == 0)
+		minlen = 1;
+
+	if (minlen > bmp->db_agsize ||
+	    start >= bmp->db_mapsize ||
+	    range->len < sb->s_blocksize)
+		return -EINVAL;
+
+	if (end >= bmp->db_mapsize)
+		end = bmp->db_mapsize - 1;
+
+	/**
+	 * we trim all ag's within the range
+	 */
+	agno = BLKTOAG(start, JFS_SBI(ip->i_sb));
+	agno_end = BLKTOAG(end, JFS_SBI(ip->i_sb));
+	while (agno <= agno_end) {
+		trimmed += dbDiscardAG(ip, agno, minlen);
+		agno++;
+	}
+	range->len = trimmed << sb->s_blocksize_bits;
+
+	return 0;
+}
diff --git a/fs/jfs/jfs_discard.h b/fs/jfs/jfs_discard.h
new file mode 100644
index 000000000..05215fa27
--- /dev/null
+++ b/fs/jfs/jfs_discard.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) Tino Reichardt, 2012
+ */
+#ifndef _H_JFS_DISCARD
+#define _H_JFS_DISCARD
+
+struct fstrim_range;
+
+extern void jfs_issue_discard(struct inode *ip, u64 blkno, u64 nblocks);
+extern int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range);
+
+#endif /* _H_JFS_DISCARD */
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
new file mode 100644
index 000000000..4d56f6081
--- /dev/null
+++ b/fs/jfs/jfs_dmap.c
@@ -0,0 +1,4061 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *   Portions Copyright (C) Tino Reichardt, 2012
+ */
+
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_dmap.h"
+#include "jfs_imap.h"
+#include "jfs_lock.h"
+#include "jfs_metapage.h"
+#include "jfs_debug.h"
+#include "jfs_discard.h"
+
+/*
+ *	SERIALIZATION of the Block Allocation Map.
+ *
+ *	the working state of the block allocation map is accessed in
+ *	two directions:
+ *
+ *	1) allocation and free requests that start at the dmap
+ *	   level and move up through the dmap control pages (i.e.
+ *	   the vast majority of requests).
+ *
+ *	2) allocation requests that start at dmap control page
+ *	   level and work down towards the dmaps.
+ *
+ *	the serialization scheme used here is as follows.
+ *
+ *	requests which start at the bottom are serialized against each
+ *	other through buffers and each requests holds onto its buffers
+ *	as it works it way up from a single dmap to the required level
+ *	of dmap control page.
+ *	requests that start at the top are serialized against each other
+ *	and request that start from the bottom by the multiple read/single
+ *	write inode lock of the bmap inode. requests starting at the top
+ *	take this lock in write mode while request starting at the bottom
+ *	take the lock in read mode.  a single top-down request may proceed
+ *	exclusively while multiple bottoms-up requests may proceed
+ *	simultaneously (under the protection of busy buffers).
+ *
+ *	in addition to information found in dmaps and dmap control pages,
+ *	the working state of the block allocation map also includes read/
+ *	write information maintained in the bmap descriptor (i.e. total
+ *	free block count, allocation group level free block counts).
+ *	a single exclusive lock (BMAP_LOCK) is used to guard this information
+ *	in the face of multiple-bottoms up requests.
+ *	(lock ordering: IREAD_LOCK, BMAP_LOCK);
+ *
+ *	accesses to the persistent state of the block allocation map (limited
+ *	to the persistent bitmaps in dmaps) is guarded by (busy) buffers.
+ */
+
+#define BMAP_LOCK_INIT(bmp)	mutex_init(&bmp->db_bmaplock)
+#define BMAP_LOCK(bmp)		mutex_lock(&bmp->db_bmaplock)
+#define BMAP_UNLOCK(bmp)	mutex_unlock(&bmp->db_bmaplock)
+
+/*
+ * forward references
+ */
+static void dbAllocBits(struct bmap * bmp, struct dmap * dp, s64 blkno,
+			int nblocks);
+static void dbSplit(dmtree_t * tp, int leafno, int splitsz, int newval);
+static int dbBackSplit(dmtree_t * tp, int leafno);
+static int dbJoin(dmtree_t * tp, int leafno, int newval);
+static void dbAdjTree(dmtree_t * tp, int leafno, int newval);
+static int dbAdjCtl(struct bmap * bmp, s64 blkno, int newval, int alloc,
+		    int level);
+static int dbAllocAny(struct bmap * bmp, s64 nblocks, int l2nb, s64 * results);
+static int dbAllocNext(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		       int nblocks);
+static int dbAllocNear(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		       int nblocks,
+		       int l2nb, s64 * results);
+static int dbAllocDmap(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		       int nblocks);
+static int dbAllocDmapLev(struct bmap * bmp, struct dmap * dp, int nblocks,
+			  int l2nb,
+			  s64 * results);
+static int dbAllocAG(struct bmap * bmp, int agno, s64 nblocks, int l2nb,
+		     s64 * results);
+static int dbAllocCtl(struct bmap * bmp, s64 nblocks, int l2nb, s64 blkno,
+		      s64 * results);
+static int dbExtend(struct inode *ip, s64 blkno, s64 nblocks, s64 addnblocks);
+static int dbFindBits(u32 word, int l2nb);
+static int dbFindCtl(struct bmap * bmp, int l2nb, int level, s64 * blkno);
+static int dbFindLeaf(dmtree_t *tp, int l2nb, int *leafidx, bool is_ctl);
+static int dbFreeBits(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		      int nblocks);
+static int dbFreeDmap(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		      int nblocks);
+static int dbMaxBud(u8 * cp);
+static int blkstol2(s64 nb);
+
+static int cntlz(u32 value);
+static int cnttz(u32 word);
+
+static int dbAllocDmapBU(struct bmap * bmp, struct dmap * dp, s64 blkno,
+			 int nblocks);
+static int dbInitDmap(struct dmap * dp, s64 blkno, int nblocks);
+static int dbInitDmapTree(struct dmap * dp);
+static int dbInitTree(struct dmaptree * dtp);
+static int dbInitDmapCtl(struct dmapctl * dcp, int level, int i);
+static int dbGetL2AGSize(s64 nblocks);
+
+/*
+ *	buddy table
+ *
+ * table used for determining buddy sizes within characters of
+ * dmap bitmap words.  the characters themselves serve as indexes
+ * into the table, with the table elements yielding the maximum
+ * binary buddy of free bits within the character.
+ */
+static const s8 budtab[256] = {
+	3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
+	2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
+	2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
+	2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, -1
+};
+
+/*
+ * NAME:	dbMount()
+ *
+ * FUNCTION:	initializate the block allocation map.
+ *
+ *		memory is allocated for the in-core bmap descriptor and
+ *		the in-core descriptor is initialized from disk.
+ *
+ * PARAMETERS:
+ *	ipbmap	- pointer to in-core inode for the block map.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOMEM	- insufficient memory
+ *	-EIO	- i/o error
+ *	-EINVAL - wrong bmap data
+ */
+int dbMount(struct inode *ipbmap)
+{
+	struct bmap *bmp;
+	struct dbmap_disk *dbmp_le;
+	struct metapage *mp;
+	int i, err;
+
+	/*
+	 * allocate/initialize the in-memory bmap descriptor
+	 */
+	/* allocate memory for the in-memory bmap descriptor */
+	bmp = kmalloc(sizeof(struct bmap), GFP_KERNEL);
+	if (bmp == NULL)
+		return -ENOMEM;
+
+	/* read the on-disk bmap descriptor. */
+	mp = read_metapage(ipbmap,
+			   BMAPBLKNO << JFS_SBI(ipbmap->i_sb)->l2nbperpage,
+			   PSIZE, 0);
+	if (mp == NULL) {
+		err = -EIO;
+		goto err_kfree_bmp;
+	}
+
+	/* copy the on-disk bmap descriptor to its in-memory version. */
+	dbmp_le = (struct dbmap_disk *) mp->data;
+	bmp->db_mapsize = le64_to_cpu(dbmp_le->dn_mapsize);
+	bmp->db_nfree = le64_to_cpu(dbmp_le->dn_nfree);
+
+	bmp->db_l2nbperpage = le32_to_cpu(dbmp_le->dn_l2nbperpage);
+	if (bmp->db_l2nbperpage > L2PSIZE - L2MINBLOCKSIZE ||
+		bmp->db_l2nbperpage < 0) {
+		err = -EINVAL;
+		goto err_release_metapage;
+	}
+
+	bmp->db_numag = le32_to_cpu(dbmp_le->dn_numag);
+	if (!bmp->db_numag) {
+		err = -EINVAL;
+		goto err_release_metapage;
+	}
+
+	bmp->db_maxlevel = le32_to_cpu(dbmp_le->dn_maxlevel);
+	bmp->db_maxag = le32_to_cpu(dbmp_le->dn_maxag);
+	bmp->db_agpref = le32_to_cpu(dbmp_le->dn_agpref);
+	if (bmp->db_maxag >= MAXAG || bmp->db_maxag < 0 ||
+		bmp->db_agpref >= MAXAG || bmp->db_agpref < 0) {
+		err = -EINVAL;
+		goto err_release_metapage;
+	}
+
+	bmp->db_aglevel = le32_to_cpu(dbmp_le->dn_aglevel);
+	bmp->db_agheight = le32_to_cpu(dbmp_le->dn_agheight);
+	bmp->db_agwidth = le32_to_cpu(dbmp_le->dn_agwidth);
+	bmp->db_agstart = le32_to_cpu(dbmp_le->dn_agstart);
+	bmp->db_agl2size = le32_to_cpu(dbmp_le->dn_agl2size);
+	if (bmp->db_agl2size > L2MAXL2SIZE - L2MAXAG ||
+	    bmp->db_agl2size < 0) {
+		err = -EINVAL;
+		goto err_release_metapage;
+	}
+
+	if (((bmp->db_mapsize - 1) >> bmp->db_agl2size) > MAXAG) {
+		err = -EINVAL;
+		goto err_release_metapage;
+	}
+
+	for (i = 0; i < MAXAG; i++)
+		bmp->db_agfree[i] = le64_to_cpu(dbmp_le->dn_agfree[i]);
+	bmp->db_agsize = le64_to_cpu(dbmp_le->dn_agsize);
+	bmp->db_maxfreebud = dbmp_le->dn_maxfreebud;
+
+	/* release the buffer. */
+	release_metapage(mp);
+
+	/* bind the bmap inode and the bmap descriptor to each other. */
+	bmp->db_ipbmap = ipbmap;
+	JFS_SBI(ipbmap->i_sb)->bmap = bmp;
+
+	memset(bmp->db_active, 0, sizeof(bmp->db_active));
+
+	/*
+	 * allocate/initialize the bmap lock
+	 */
+	BMAP_LOCK_INIT(bmp);
+
+	return (0);
+
+err_release_metapage:
+	release_metapage(mp);
+err_kfree_bmp:
+	kfree(bmp);
+	return err;
+}
+
+
+/*
+ * NAME:	dbUnmount()
+ *
+ * FUNCTION:	terminate the block allocation map in preparation for
+ *		file system unmount.
+ *
+ *		the in-core bmap descriptor is written to disk and
+ *		the memory for this descriptor is freed.
+ *
+ * PARAMETERS:
+ *	ipbmap	- pointer to in-core inode for the block map.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error
+ */
+int dbUnmount(struct inode *ipbmap, int mounterror)
+{
+	struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap;
+
+	if (!(mounterror || isReadOnly(ipbmap)))
+		dbSync(ipbmap);
+
+	/*
+	 * Invalidate the page cache buffers
+	 */
+	truncate_inode_pages(ipbmap->i_mapping, 0);
+
+	/* free the memory for the in-memory bmap. */
+	kfree(bmp);
+	JFS_SBI(ipbmap->i_sb)->bmap = NULL;
+
+	return (0);
+}
+
+/*
+ *	dbSync()
+ */
+int dbSync(struct inode *ipbmap)
+{
+	struct dbmap_disk *dbmp_le;
+	struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap;
+	struct metapage *mp;
+	int i;
+
+	/*
+	 * write bmap global control page
+	 */
+	/* get the buffer for the on-disk bmap descriptor. */
+	mp = read_metapage(ipbmap,
+			   BMAPBLKNO << JFS_SBI(ipbmap->i_sb)->l2nbperpage,
+			   PSIZE, 0);
+	if (mp == NULL) {
+		jfs_err("dbSync: read_metapage failed!");
+		return -EIO;
+	}
+	/* copy the in-memory version of the bmap to the on-disk version */
+	dbmp_le = (struct dbmap_disk *) mp->data;
+	dbmp_le->dn_mapsize = cpu_to_le64(bmp->db_mapsize);
+	dbmp_le->dn_nfree = cpu_to_le64(bmp->db_nfree);
+	dbmp_le->dn_l2nbperpage = cpu_to_le32(bmp->db_l2nbperpage);
+	dbmp_le->dn_numag = cpu_to_le32(bmp->db_numag);
+	dbmp_le->dn_maxlevel = cpu_to_le32(bmp->db_maxlevel);
+	dbmp_le->dn_maxag = cpu_to_le32(bmp->db_maxag);
+	dbmp_le->dn_agpref = cpu_to_le32(bmp->db_agpref);
+	dbmp_le->dn_aglevel = cpu_to_le32(bmp->db_aglevel);
+	dbmp_le->dn_agheight = cpu_to_le32(bmp->db_agheight);
+	dbmp_le->dn_agwidth = cpu_to_le32(bmp->db_agwidth);
+	dbmp_le->dn_agstart = cpu_to_le32(bmp->db_agstart);
+	dbmp_le->dn_agl2size = cpu_to_le32(bmp->db_agl2size);
+	for (i = 0; i < MAXAG; i++)
+		dbmp_le->dn_agfree[i] = cpu_to_le64(bmp->db_agfree[i]);
+	dbmp_le->dn_agsize = cpu_to_le64(bmp->db_agsize);
+	dbmp_le->dn_maxfreebud = bmp->db_maxfreebud;
+
+	/* write the buffer */
+	write_metapage(mp);
+
+	/*
+	 * write out dirty pages of bmap
+	 */
+	filemap_write_and_wait(ipbmap->i_mapping);
+
+	diWriteSpecial(ipbmap, 0);
+
+	return (0);
+}
+
+/*
+ * NAME:	dbFree()
+ *
+ * FUNCTION:	free the specified block range from the working block
+ *		allocation map.
+ *
+ *		the blocks will be free from the working map one dmap
+ *		at a time.
+ *
+ * PARAMETERS:
+ *	ip	- pointer to in-core inode;
+ *	blkno	- starting block number to be freed.
+ *	nblocks	- number of blocks to be freed.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error
+ */
+int dbFree(struct inode *ip, s64 blkno, s64 nblocks)
+{
+	struct metapage *mp;
+	struct dmap *dp;
+	int nb, rc;
+	s64 lblkno, rem;
+	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
+	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
+	struct super_block *sb = ipbmap->i_sb;
+
+	IREAD_LOCK(ipbmap, RDWRLOCK_DMAP);
+
+	/* block to be freed better be within the mapsize. */
+	if (unlikely((blkno == 0) || (blkno + nblocks > bmp->db_mapsize))) {
+		IREAD_UNLOCK(ipbmap);
+		printk(KERN_ERR "blkno = %Lx, nblocks = %Lx\n",
+		       (unsigned long long) blkno,
+		       (unsigned long long) nblocks);
+		jfs_error(ip->i_sb, "block to be freed is outside the map\n");
+		return -EIO;
+	}
+
+	/**
+	 * TRIM the blocks, when mounted with discard option
+	 */
+	if (JFS_SBI(sb)->flag & JFS_DISCARD)
+		if (JFS_SBI(sb)->minblks_trim <= nblocks)
+			jfs_issue_discard(ipbmap, blkno, nblocks);
+
+	/*
+	 * free the blocks a dmap at a time.
+	 */
+	mp = NULL;
+	for (rem = nblocks; rem > 0; rem -= nb, blkno += nb) {
+		/* release previous dmap if any */
+		if (mp) {
+			write_metapage(mp);
+		}
+
+		/* get the buffer for the current dmap. */
+		lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage);
+		mp = read_metapage(ipbmap, lblkno, PSIZE, 0);
+		if (mp == NULL) {
+			IREAD_UNLOCK(ipbmap);
+			return -EIO;
+		}
+		dp = (struct dmap *) mp->data;
+
+		/* determine the number of blocks to be freed from
+		 * this dmap.
+		 */
+		nb = min(rem, BPERDMAP - (blkno & (BPERDMAP - 1)));
+
+		/* free the blocks. */
+		if ((rc = dbFreeDmap(bmp, dp, blkno, nb))) {
+			jfs_error(ip->i_sb, "error in block map\n");
+			release_metapage(mp);
+			IREAD_UNLOCK(ipbmap);
+			return (rc);
+		}
+	}
+
+	/* write the last buffer. */
+	if (mp)
+		write_metapage(mp);
+
+	IREAD_UNLOCK(ipbmap);
+
+	return (0);
+}
+
+
+/*
+ * NAME:	dbUpdatePMap()
+ *
+ * FUNCTION:	update the allocation state (free or allocate) of the
+ *		specified block range in the persistent block allocation map.
+ *
+ *		the blocks will be updated in the persistent map one
+ *		dmap at a time.
+ *
+ * PARAMETERS:
+ *	ipbmap	- pointer to in-core inode for the block map.
+ *	free	- 'true' if block range is to be freed from the persistent
+ *		  map; 'false' if it is to be allocated.
+ *	blkno	- starting block number of the range.
+ *	nblocks	- number of contiguous blocks in the range.
+ *	tblk	- transaction block;
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error
+ */
+int
+dbUpdatePMap(struct inode *ipbmap,
+	     int free, s64 blkno, s64 nblocks, struct tblock * tblk)
+{
+	int nblks, dbitno, wbitno, rbits;
+	int word, nbits, nwords;
+	struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap;
+	s64 lblkno, rem, lastlblkno;
+	u32 mask;
+	struct dmap *dp;
+	struct metapage *mp;
+	struct jfs_log *log;
+	int lsn, difft, diffp;
+	unsigned long flags;
+
+	/* the blocks better be within the mapsize. */
+	if (blkno + nblocks > bmp->db_mapsize) {
+		printk(KERN_ERR "blkno = %Lx, nblocks = %Lx\n",
+		       (unsigned long long) blkno,
+		       (unsigned long long) nblocks);
+		jfs_error(ipbmap->i_sb, "blocks are outside the map\n");
+		return -EIO;
+	}
+
+	/* compute delta of transaction lsn from log syncpt */
+	lsn = tblk->lsn;
+	log = (struct jfs_log *) JFS_SBI(tblk->sb)->log;
+	logdiff(difft, lsn, log);
+
+	/*
+	 * update the block state a dmap at a time.
+	 */
+	mp = NULL;
+	lastlblkno = 0;
+	for (rem = nblocks; rem > 0; rem -= nblks, blkno += nblks) {
+		/* get the buffer for the current dmap. */
+		lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage);
+		if (lblkno != lastlblkno) {
+			if (mp) {
+				write_metapage(mp);
+			}
+
+			mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE,
+					   0);
+			if (mp == NULL)
+				return -EIO;
+			metapage_wait_for_io(mp);
+		}
+		dp = (struct dmap *) mp->data;
+
+		/* determine the bit number and word within the dmap of
+		 * the starting block.  also determine how many blocks
+		 * are to be updated within this dmap.
+		 */
+		dbitno = blkno & (BPERDMAP - 1);
+		word = dbitno >> L2DBWORD;
+		nblks = min(rem, (s64)BPERDMAP - dbitno);
+
+		/* update the bits of the dmap words. the first and last
+		 * words may only have a subset of their bits updated. if
+		 * this is the case, we'll work against that word (i.e.
+		 * partial first and/or last) only in a single pass.  a
+		 * single pass will also be used to update all words that
+		 * are to have all their bits updated.
+		 */
+		for (rbits = nblks; rbits > 0;
+		     rbits -= nbits, dbitno += nbits) {
+			/* determine the bit number within the word and
+			 * the number of bits within the word.
+			 */
+			wbitno = dbitno & (DBWORD - 1);
+			nbits = min(rbits, DBWORD - wbitno);
+
+			/* check if only part of the word is to be updated. */
+			if (nbits < DBWORD) {
+				/* update (free or allocate) the bits
+				 * in this word.
+				 */
+				mask =
+				    (ONES << (DBWORD - nbits) >> wbitno);
+				if (free)
+					dp->pmap[word] &=
+					    cpu_to_le32(~mask);
+				else
+					dp->pmap[word] |=
+					    cpu_to_le32(mask);
+
+				word += 1;
+			} else {
+				/* one or more words are to have all
+				 * their bits updated.  determine how
+				 * many words and how many bits.
+				 */
+				nwords = rbits >> L2DBWORD;
+				nbits = nwords << L2DBWORD;
+
+				/* update (free or allocate) the bits
+				 * in these words.
+				 */
+				if (free)
+					memset(&dp->pmap[word], 0,
+					       nwords * 4);
+				else
+					memset(&dp->pmap[word], (int) ONES,
+					       nwords * 4);
+
+				word += nwords;
+			}
+		}
+
+		/*
+		 * update dmap lsn
+		 */
+		if (lblkno == lastlblkno)
+			continue;
+
+		lastlblkno = lblkno;
+
+		LOGSYNC_LOCK(log, flags);
+		if (mp->lsn != 0) {
+			/* inherit older/smaller lsn */
+			logdiff(diffp, mp->lsn, log);
+			if (difft < diffp) {
+				mp->lsn = lsn;
+
+				/* move bp after tblock in logsync list */
+				list_move(&mp->synclist, &tblk->synclist);
+			}
+
+			/* inherit younger/larger clsn */
+			logdiff(difft, tblk->clsn, log);
+			logdiff(diffp, mp->clsn, log);
+			if (difft > diffp)
+				mp->clsn = tblk->clsn;
+		} else {
+			mp->log = log;
+			mp->lsn = lsn;
+
+			/* insert bp after tblock in logsync list */
+			log->count++;
+			list_add(&mp->synclist, &tblk->synclist);
+
+			mp->clsn = tblk->clsn;
+		}
+		LOGSYNC_UNLOCK(log, flags);
+	}
+
+	/* write the last buffer. */
+	if (mp) {
+		write_metapage(mp);
+	}
+
+	return (0);
+}
+
+
+/*
+ * NAME:	dbNextAG()
+ *
+ * FUNCTION:	find the preferred allocation group for new allocations.
+ *
+ *		Within the allocation groups, we maintain a preferred
+ *		allocation group which consists of a group with at least
+ *		average free space.  It is the preferred group that we target
+ *		new inode allocation towards.  The tie-in between inode
+ *		allocation and block allocation occurs as we allocate the
+ *		first (data) block of an inode and specify the inode (block)
+ *		as the allocation hint for this block.
+ *
+ *		We try to avoid having more than one open file growing in
+ *		an allocation group, as this will lead to fragmentation.
+ *		This differs from the old OS/2 method of trying to keep
+ *		empty ags around for large allocations.
+ *
+ * PARAMETERS:
+ *	ipbmap	- pointer to in-core inode for the block map.
+ *
+ * RETURN VALUES:
+ *	the preferred allocation group number.
+ */
+int dbNextAG(struct inode *ipbmap)
+{
+	s64 avgfree;
+	int agpref;
+	s64 hwm = 0;
+	int i;
+	int next_best = -1;
+	struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap;
+
+	BMAP_LOCK(bmp);
+
+	/* determine the average number of free blocks within the ags. */
+	avgfree = (u32)bmp->db_nfree / bmp->db_numag;
+
+	/*
+	 * if the current preferred ag does not have an active allocator
+	 * and has at least average freespace, return it
+	 */
+	agpref = bmp->db_agpref;
+	if ((atomic_read(&bmp->db_active[agpref]) == 0) &&
+	    (bmp->db_agfree[agpref] >= avgfree))
+		goto unlock;
+
+	/* From the last preferred ag, find the next one with at least
+	 * average free space.
+	 */
+	for (i = 0 ; i < bmp->db_numag; i++, agpref++) {
+		if (agpref == bmp->db_numag)
+			agpref = 0;
+
+		if (atomic_read(&bmp->db_active[agpref]))
+			/* open file is currently growing in this ag */
+			continue;
+		if (bmp->db_agfree[agpref] >= avgfree) {
+			/* Return this one */
+			bmp->db_agpref = agpref;
+			goto unlock;
+		} else if (bmp->db_agfree[agpref] > hwm) {
+			/* Less than avg. freespace, but best so far */
+			hwm = bmp->db_agfree[agpref];
+			next_best = agpref;
+		}
+	}
+
+	/*
+	 * If no inactive ag was found with average freespace, use the
+	 * next best
+	 */
+	if (next_best != -1)
+		bmp->db_agpref = next_best;
+	/* else leave db_agpref unchanged */
+unlock:
+	BMAP_UNLOCK(bmp);
+
+	/* return the preferred group.
+	 */
+	return (bmp->db_agpref);
+}
+
+/*
+ * NAME:	dbAlloc()
+ *
+ * FUNCTION:	attempt to allocate a specified number of contiguous free
+ *		blocks from the working allocation block map.
+ *
+ *		the block allocation policy uses hints and a multi-step
+ *		approach.
+ *
+ *		for allocation requests smaller than the number of blocks
+ *		per dmap, we first try to allocate the new blocks
+ *		immediately following the hint.  if these blocks are not
+ *		available, we try to allocate blocks near the hint.  if
+ *		no blocks near the hint are available, we next try to
+ *		allocate within the same dmap as contains the hint.
+ *
+ *		if no blocks are available in the dmap or the allocation
+ *		request is larger than the dmap size, we try to allocate
+ *		within the same allocation group as contains the hint. if
+ *		this does not succeed, we finally try to allocate anywhere
+ *		within the aggregate.
+ *
+ *		we also try to allocate anywhere within the aggregate
+ *		for allocation requests larger than the allocation group
+ *		size or requests that specify no hint value.
+ *
+ * PARAMETERS:
+ *	ip	- pointer to in-core inode;
+ *	hint	- allocation hint.
+ *	nblocks	- number of contiguous blocks in the range.
+ *	results	- on successful return, set to the starting block number
+ *		  of the newly allocated contiguous range.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ */
+int dbAlloc(struct inode *ip, s64 hint, s64 nblocks, s64 * results)
+{
+	int rc, agno;
+	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
+	struct bmap *bmp;
+	struct metapage *mp;
+	s64 lblkno, blkno;
+	struct dmap *dp;
+	int l2nb;
+	s64 mapSize;
+	int writers;
+
+	/* assert that nblocks is valid */
+	assert(nblocks > 0);
+
+	/* get the log2 number of blocks to be allocated.
+	 * if the number of blocks is not a log2 multiple,
+	 * it will be rounded up to the next log2 multiple.
+	 */
+	l2nb = BLKSTOL2(nblocks);
+
+	bmp = JFS_SBI(ip->i_sb)->bmap;
+
+	mapSize = bmp->db_mapsize;
+
+	/* the hint should be within the map */
+	if (hint >= mapSize) {
+		jfs_error(ip->i_sb, "the hint is outside the map\n");
+		return -EIO;
+	}
+
+	/* if the number of blocks to be allocated is greater than the
+	 * allocation group size, try to allocate anywhere.
+	 */
+	if (l2nb > bmp->db_agl2size) {
+		IWRITE_LOCK(ipbmap, RDWRLOCK_DMAP);
+
+		rc = dbAllocAny(bmp, nblocks, l2nb, results);
+
+		goto write_unlock;
+	}
+
+	/*
+	 * If no hint, let dbNextAG recommend an allocation group
+	 */
+	if (hint == 0)
+		goto pref_ag;
+
+	/* we would like to allocate close to the hint.  adjust the
+	 * hint to the block following the hint since the allocators
+	 * will start looking for free space starting at this point.
+	 */
+	blkno = hint + 1;
+
+	if (blkno >= bmp->db_mapsize)
+		goto pref_ag;
+
+	agno = blkno >> bmp->db_agl2size;
+
+	/* check if blkno crosses over into a new allocation group.
+	 * if so, check if we should allow allocations within this
+	 * allocation group.
+	 */
+	if ((blkno & (bmp->db_agsize - 1)) == 0)
+		/* check if the AG is currently being written to.
+		 * if so, call dbNextAG() to find a non-busy
+		 * AG with sufficient free space.
+		 */
+		if (atomic_read(&bmp->db_active[agno]))
+			goto pref_ag;
+
+	/* check if the allocation request size can be satisfied from a
+	 * single dmap.  if so, try to allocate from the dmap containing
+	 * the hint using a tiered strategy.
+	 */
+	if (nblocks <= BPERDMAP) {
+		IREAD_LOCK(ipbmap, RDWRLOCK_DMAP);
+
+		/* get the buffer for the dmap containing the hint.
+		 */
+		rc = -EIO;
+		lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage);
+		mp = read_metapage(ipbmap, lblkno, PSIZE, 0);
+		if (mp == NULL)
+			goto read_unlock;
+
+		dp = (struct dmap *) mp->data;
+
+		/* first, try to satisfy the allocation request with the
+		 * blocks beginning at the hint.
+		 */
+		if ((rc = dbAllocNext(bmp, dp, blkno, (int) nblocks))
+		    != -ENOSPC) {
+			if (rc == 0) {
+				*results = blkno;
+				mark_metapage_dirty(mp);
+			}
+
+			release_metapage(mp);
+			goto read_unlock;
+		}
+
+		writers = atomic_read(&bmp->db_active[agno]);
+		if ((writers > 1) ||
+		    ((writers == 1) && (JFS_IP(ip)->active_ag != agno))) {
+			/*
+			 * Someone else is writing in this allocation
+			 * group.  To avoid fragmenting, try another ag
+			 */
+			release_metapage(mp);
+			IREAD_UNLOCK(ipbmap);
+			goto pref_ag;
+		}
+
+		/* next, try to satisfy the allocation request with blocks
+		 * near the hint.
+		 */
+		if ((rc =
+		     dbAllocNear(bmp, dp, blkno, (int) nblocks, l2nb, results))
+		    != -ENOSPC) {
+			if (rc == 0)
+				mark_metapage_dirty(mp);
+
+			release_metapage(mp);
+			goto read_unlock;
+		}
+
+		/* try to satisfy the allocation request with blocks within
+		 * the same dmap as the hint.
+		 */
+		if ((rc = dbAllocDmapLev(bmp, dp, (int) nblocks, l2nb, results))
+		    != -ENOSPC) {
+			if (rc == 0)
+				mark_metapage_dirty(mp);
+
+			release_metapage(mp);
+			goto read_unlock;
+		}
+
+		release_metapage(mp);
+		IREAD_UNLOCK(ipbmap);
+	}
+
+	/* try to satisfy the allocation request with blocks within
+	 * the same allocation group as the hint.
+	 */
+	IWRITE_LOCK(ipbmap, RDWRLOCK_DMAP);
+	if ((rc = dbAllocAG(bmp, agno, nblocks, l2nb, results)) != -ENOSPC)
+		goto write_unlock;
+
+	IWRITE_UNLOCK(ipbmap);
+
+
+      pref_ag:
+	/*
+	 * Let dbNextAG recommend a preferred allocation group
+	 */
+	agno = dbNextAG(ipbmap);
+	IWRITE_LOCK(ipbmap, RDWRLOCK_DMAP);
+
+	/* Try to allocate within this allocation group.  if that fails, try to
+	 * allocate anywhere in the map.
+	 */
+	if ((rc = dbAllocAG(bmp, agno, nblocks, l2nb, results)) == -ENOSPC)
+		rc = dbAllocAny(bmp, nblocks, l2nb, results);
+
+      write_unlock:
+	IWRITE_UNLOCK(ipbmap);
+
+	return (rc);
+
+      read_unlock:
+	IREAD_UNLOCK(ipbmap);
+
+	return (rc);
+}
+
+/*
+ * NAME:	dbReAlloc()
+ *
+ * FUNCTION:	attempt to extend a current allocation by a specified
+ *		number of blocks.
+ *
+ *		this routine attempts to satisfy the allocation request
+ *		by first trying to extend the existing allocation in
+ *		place by allocating the additional blocks as the blocks
+ *		immediately following the current allocation.  if these
+ *		blocks are not available, this routine will attempt to
+ *		allocate a new set of contiguous blocks large enough
+ *		to cover the existing allocation plus the additional
+ *		number of blocks required.
+ *
+ * PARAMETERS:
+ *	ip	    -  pointer to in-core inode requiring allocation.
+ *	blkno	    -  starting block of the current allocation.
+ *	nblocks	    -  number of contiguous blocks within the current
+ *		       allocation.
+ *	addnblocks  -  number of blocks to add to the allocation.
+ *	results	-      on successful return, set to the starting block number
+ *		       of the existing allocation if the existing allocation
+ *		       was extended in place or to a newly allocated contiguous
+ *		       range if the existing allocation could not be extended
+ *		       in place.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ */
+int
+dbReAlloc(struct inode *ip,
+	  s64 blkno, s64 nblocks, s64 addnblocks, s64 * results)
+{
+	int rc;
+
+	/* try to extend the allocation in place.
+	 */
+	if ((rc = dbExtend(ip, blkno, nblocks, addnblocks)) == 0) {
+		*results = blkno;
+		return (0);
+	} else {
+		if (rc != -ENOSPC)
+			return (rc);
+	}
+
+	/* could not extend the allocation in place, so allocate a
+	 * new set of blocks for the entire request (i.e. try to get
+	 * a range of contiguous blocks large enough to cover the
+	 * existing allocation plus the additional blocks.)
+	 */
+	return (dbAlloc
+		(ip, blkno + nblocks - 1, addnblocks + nblocks, results));
+}
+
+
+/*
+ * NAME:	dbExtend()
+ *
+ * FUNCTION:	attempt to extend a current allocation by a specified
+ *		number of blocks.
+ *
+ *		this routine attempts to satisfy the allocation request
+ *		by first trying to extend the existing allocation in
+ *		place by allocating the additional blocks as the blocks
+ *		immediately following the current allocation.
+ *
+ * PARAMETERS:
+ *	ip	    -  pointer to in-core inode requiring allocation.
+ *	blkno	    -  starting block of the current allocation.
+ *	nblocks	    -  number of contiguous blocks within the current
+ *		       allocation.
+ *	addnblocks  -  number of blocks to add to the allocation.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ */
+static int dbExtend(struct inode *ip, s64 blkno, s64 nblocks, s64 addnblocks)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+	s64 lblkno, lastblkno, extblkno;
+	uint rel_block;
+	struct metapage *mp;
+	struct dmap *dp;
+	int rc;
+	struct inode *ipbmap = sbi->ipbmap;
+	struct bmap *bmp;
+
+	/*
+	 * We don't want a non-aligned extent to cross a page boundary
+	 */
+	if (((rel_block = blkno & (sbi->nbperpage - 1))) &&
+	    (rel_block + nblocks + addnblocks > sbi->nbperpage))
+		return -ENOSPC;
+
+	/* get the last block of the current allocation */
+	lastblkno = blkno + nblocks - 1;
+
+	/* determine the block number of the block following
+	 * the existing allocation.
+	 */
+	extblkno = lastblkno + 1;
+
+	IREAD_LOCK(ipbmap, RDWRLOCK_DMAP);
+
+	/* better be within the file system */
+	bmp = sbi->bmap;
+	if (lastblkno < 0 || lastblkno >= bmp->db_mapsize) {
+		IREAD_UNLOCK(ipbmap);
+		jfs_error(ip->i_sb, "the block is outside the filesystem\n");
+		return -EIO;
+	}
+
+	/* we'll attempt to extend the current allocation in place by
+	 * allocating the additional blocks as the blocks immediately
+	 * following the current allocation.  we only try to extend the
+	 * current allocation in place if the number of additional blocks
+	 * can fit into a dmap, the last block of the current allocation
+	 * is not the last block of the file system, and the start of the
+	 * inplace extension is not on an allocation group boundary.
+	 */
+	if (addnblocks > BPERDMAP || extblkno >= bmp->db_mapsize ||
+	    (extblkno & (bmp->db_agsize - 1)) == 0) {
+		IREAD_UNLOCK(ipbmap);
+		return -ENOSPC;
+	}
+
+	/* get the buffer for the dmap containing the first block
+	 * of the extension.
+	 */
+	lblkno = BLKTODMAP(extblkno, bmp->db_l2nbperpage);
+	mp = read_metapage(ipbmap, lblkno, PSIZE, 0);
+	if (mp == NULL) {
+		IREAD_UNLOCK(ipbmap);
+		return -EIO;
+	}
+
+	dp = (struct dmap *) mp->data;
+
+	/* try to allocate the blocks immediately following the
+	 * current allocation.
+	 */
+	rc = dbAllocNext(bmp, dp, extblkno, (int) addnblocks);
+
+	IREAD_UNLOCK(ipbmap);
+
+	/* were we successful ? */
+	if (rc == 0)
+		write_metapage(mp);
+	else
+		/* we were not successful */
+		release_metapage(mp);
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	dbAllocNext()
+ *
+ * FUNCTION:	attempt to allocate the blocks of the specified block
+ *		range within a dmap.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	dp	-  pointer to dmap.
+ *	blkno	-  starting block number of the range.
+ *	nblocks	-  number of contiguous free blocks of the range.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ *
+ * serialization: IREAD_LOCK(ipbmap) held on entry/exit;
+ */
+static int dbAllocNext(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		       int nblocks)
+{
+	int dbitno, word, rembits, nb, nwords, wbitno, nw;
+	int l2size;
+	s8 *leaf;
+	u32 mask;
+
+	if (dp->tree.leafidx != cpu_to_le32(LEAFIND)) {
+		jfs_error(bmp->db_ipbmap->i_sb, "Corrupt dmap page\n");
+		return -EIO;
+	}
+
+	/* pick up a pointer to the leaves of the dmap tree.
+	 */
+	leaf = dp->tree.stree + le32_to_cpu(dp->tree.leafidx);
+
+	/* determine the bit number and word within the dmap of the
+	 * starting block.
+	 */
+	dbitno = blkno & (BPERDMAP - 1);
+	word = dbitno >> L2DBWORD;
+
+	/* check if the specified block range is contained within
+	 * this dmap.
+	 */
+	if (dbitno + nblocks > BPERDMAP)
+		return -ENOSPC;
+
+	/* check if the starting leaf indicates that anything
+	 * is free.
+	 */
+	if (leaf[word] == NOFREE)
+		return -ENOSPC;
+
+	/* check the dmaps words corresponding to block range to see
+	 * if the block range is free.  not all bits of the first and
+	 * last words may be contained within the block range.  if this
+	 * is the case, we'll work against those words (i.e. partial first
+	 * and/or last) on an individual basis (a single pass) and examine
+	 * the actual bits to determine if they are free.  a single pass
+	 * will be used for all dmap words fully contained within the
+	 * specified range.  within this pass, the leaves of the dmap
+	 * tree will be examined to determine if the blocks are free. a
+	 * single leaf may describe the free space of multiple dmap
+	 * words, so we may visit only a subset of the actual leaves
+	 * corresponding to the dmap words of the block range.
+	 */
+	for (rembits = nblocks; rembits > 0; rembits -= nb, dbitno += nb) {
+		/* determine the bit number within the word and
+		 * the number of bits within the word.
+		 */
+		wbitno = dbitno & (DBWORD - 1);
+		nb = min(rembits, DBWORD - wbitno);
+
+		/* check if only part of the word is to be examined.
+		 */
+		if (nb < DBWORD) {
+			/* check if the bits are free.
+			 */
+			mask = (ONES << (DBWORD - nb) >> wbitno);
+			if ((mask & ~le32_to_cpu(dp->wmap[word])) != mask)
+				return -ENOSPC;
+
+			word += 1;
+		} else {
+			/* one or more dmap words are fully contained
+			 * within the block range.  determine how many
+			 * words and how many bits.
+			 */
+			nwords = rembits >> L2DBWORD;
+			nb = nwords << L2DBWORD;
+
+			/* now examine the appropriate leaves to determine
+			 * if the blocks are free.
+			 */
+			while (nwords > 0) {
+				/* does the leaf describe any free space ?
+				 */
+				if (leaf[word] < BUDMIN)
+					return -ENOSPC;
+
+				/* determine the l2 number of bits provided
+				 * by this leaf.
+				 */
+				l2size =
+				    min_t(int, leaf[word], NLSTOL2BSZ(nwords));
+
+				/* determine how many words were handled.
+				 */
+				nw = BUDSIZE(l2size, BUDMIN);
+
+				nwords -= nw;
+				word += nw;
+			}
+		}
+	}
+
+	/* allocate the blocks.
+	 */
+	return (dbAllocDmap(bmp, dp, blkno, nblocks));
+}
+
+
+/*
+ * NAME:	dbAllocNear()
+ *
+ * FUNCTION:	attempt to allocate a number of contiguous free blocks near
+ *		a specified block (hint) within a dmap.
+ *
+ *		starting with the dmap leaf that covers the hint, we'll
+ *		check the next four contiguous leaves for sufficient free
+ *		space.  if sufficient free space is found, we'll allocate
+ *		the desired free space.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	dp	-  pointer to dmap.
+ *	blkno	-  block number to allocate near.
+ *	nblocks	-  actual number of contiguous free blocks desired.
+ *	l2nb	-  log2 number of contiguous free blocks desired.
+ *	results	-  on successful return, set to the starting block number
+ *		   of the newly allocated range.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ *
+ * serialization: IREAD_LOCK(ipbmap) held on entry/exit;
+ */
+static int
+dbAllocNear(struct bmap * bmp,
+	    struct dmap * dp, s64 blkno, int nblocks, int l2nb, s64 * results)
+{
+	int word, lword, rc;
+	s8 *leaf;
+
+	if (dp->tree.leafidx != cpu_to_le32(LEAFIND)) {
+		jfs_error(bmp->db_ipbmap->i_sb, "Corrupt dmap page\n");
+		return -EIO;
+	}
+
+	leaf = dp->tree.stree + le32_to_cpu(dp->tree.leafidx);
+
+	/* determine the word within the dmap that holds the hint
+	 * (i.e. blkno).  also, determine the last word in the dmap
+	 * that we'll include in our examination.
+	 */
+	word = (blkno & (BPERDMAP - 1)) >> L2DBWORD;
+	lword = min(word + 4, LPERDMAP);
+
+	/* examine the leaves for sufficient free space.
+	 */
+	for (; word < lword; word++) {
+		/* does the leaf describe sufficient free space ?
+		 */
+		if (leaf[word] < l2nb)
+			continue;
+
+		/* determine the block number within the file system
+		 * of the first block described by this dmap word.
+		 */
+		blkno = le64_to_cpu(dp->start) + (word << L2DBWORD);
+
+		/* if not all bits of the dmap word are free, get the
+		 * starting bit number within the dmap word of the required
+		 * string of free bits and adjust the block number with the
+		 * value.
+		 */
+		if (leaf[word] < BUDMIN)
+			blkno +=
+			    dbFindBits(le32_to_cpu(dp->wmap[word]), l2nb);
+
+		/* allocate the blocks.
+		 */
+		if ((rc = dbAllocDmap(bmp, dp, blkno, nblocks)) == 0)
+			*results = blkno;
+
+		return (rc);
+	}
+
+	return -ENOSPC;
+}
+
+
+/*
+ * NAME:	dbAllocAG()
+ *
+ * FUNCTION:	attempt to allocate the specified number of contiguous
+ *		free blocks within the specified allocation group.
+ *
+ *		unless the allocation group size is equal to the number
+ *		of blocks per dmap, the dmap control pages will be used to
+ *		find the required free space, if available.  we start the
+ *		search at the highest dmap control page level which
+ *		distinctly describes the allocation group's free space
+ *		(i.e. the highest level at which the allocation group's
+ *		free space is not mixed in with that of any other group).
+ *		in addition, we start the search within this level at a
+ *		height of the dmapctl dmtree at which the nodes distinctly
+ *		describe the allocation group's free space.  at this height,
+ *		the allocation group's free space may be represented by 1
+ *		or two sub-trees, depending on the allocation group size.
+ *		we search the top nodes of these subtrees left to right for
+ *		sufficient free space.  if sufficient free space is found,
+ *		the subtree is searched to find the leftmost leaf that
+ *		has free space.  once we have made it to the leaf, we
+ *		move the search to the next lower level dmap control page
+ *		corresponding to this leaf.  we continue down the dmap control
+ *		pages until we find the dmap that contains or starts the
+ *		sufficient free space and we allocate at this dmap.
+ *
+ *		if the allocation group size is equal to the dmap size,
+ *		we'll start at the dmap corresponding to the allocation
+ *		group and attempt the allocation at this level.
+ *
+ *		the dmap control page search is also not performed if the
+ *		allocation group is completely free and we go to the first
+ *		dmap of the allocation group to do the allocation.  this is
+ *		done because the allocation group may be part (not the first
+ *		part) of a larger binary buddy system, causing the dmap
+ *		control pages to indicate no free space (NOFREE) within
+ *		the allocation group.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	agno	- allocation group number.
+ *	nblocks	-  actual number of contiguous free blocks desired.
+ *	l2nb	-  log2 number of contiguous free blocks desired.
+ *	results	-  on successful return, set to the starting block number
+ *		   of the newly allocated range.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ *
+ * note: IWRITE_LOCK(ipmap) held on entry/exit;
+ */
+static int
+dbAllocAG(struct bmap * bmp, int agno, s64 nblocks, int l2nb, s64 * results)
+{
+	struct metapage *mp;
+	struct dmapctl *dcp;
+	int rc, ti, i, k, m, n, agperlev;
+	s64 blkno, lblkno;
+	int budmin;
+
+	/* allocation request should not be for more than the
+	 * allocation group size.
+	 */
+	if (l2nb > bmp->db_agl2size) {
+		jfs_error(bmp->db_ipbmap->i_sb,
+			  "allocation request is larger than the allocation group size\n");
+		return -EIO;
+	}
+
+	/* determine the starting block number of the allocation
+	 * group.
+	 */
+	blkno = (s64) agno << bmp->db_agl2size;
+
+	/* check if the allocation group size is the minimum allocation
+	 * group size or if the allocation group is completely free. if
+	 * the allocation group size is the minimum size of BPERDMAP (i.e.
+	 * 1 dmap), there is no need to search the dmap control page (below)
+	 * that fully describes the allocation group since the allocation
+	 * group is already fully described by a dmap.  in this case, we
+	 * just call dbAllocCtl() to search the dmap tree and allocate the
+	 * required space if available.
+	 *
+	 * if the allocation group is completely free, dbAllocCtl() is
+	 * also called to allocate the required space.  this is done for
+	 * two reasons.  first, it makes no sense searching the dmap control
+	 * pages for free space when we know that free space exists.  second,
+	 * the dmap control pages may indicate that the allocation group
+	 * has no free space if the allocation group is part (not the first
+	 * part) of a larger binary buddy system.
+	 */
+	if (bmp->db_agsize == BPERDMAP
+	    || bmp->db_agfree[agno] == bmp->db_agsize) {
+		rc = dbAllocCtl(bmp, nblocks, l2nb, blkno, results);
+		if ((rc == -ENOSPC) &&
+		    (bmp->db_agfree[agno] == bmp->db_agsize)) {
+			printk(KERN_ERR "blkno = %Lx, blocks = %Lx\n",
+			       (unsigned long long) blkno,
+			       (unsigned long long) nblocks);
+			jfs_error(bmp->db_ipbmap->i_sb,
+				  "dbAllocCtl failed in free AG\n");
+		}
+		return (rc);
+	}
+
+	/* the buffer for the dmap control page that fully describes the
+	 * allocation group.
+	 */
+	lblkno = BLKTOCTL(blkno, bmp->db_l2nbperpage, bmp->db_aglevel);
+	mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0);
+	if (mp == NULL)
+		return -EIO;
+	dcp = (struct dmapctl *) mp->data;
+	budmin = dcp->budmin;
+
+	if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) {
+		jfs_error(bmp->db_ipbmap->i_sb, "Corrupt dmapctl page\n");
+		release_metapage(mp);
+		return -EIO;
+	}
+
+	/* search the subtree(s) of the dmap control page that describes
+	 * the allocation group, looking for sufficient free space.  to begin,
+	 * determine how many allocation groups are represented in a dmap
+	 * control page at the control page level (i.e. L0, L1, L2) that
+	 * fully describes an allocation group. next, determine the starting
+	 * tree index of this allocation group within the control page.
+	 */
+	agperlev =
+	    (1 << (L2LPERCTL - (bmp->db_agheight << 1))) / bmp->db_agwidth;
+	ti = bmp->db_agstart + bmp->db_agwidth * (agno & (agperlev - 1));
+
+	/* dmap control page trees fan-out by 4 and a single allocation
+	 * group may be described by 1 or 2 subtrees within the ag level
+	 * dmap control page, depending upon the ag size. examine the ag's
+	 * subtrees for sufficient free space, starting with the leftmost
+	 * subtree.
+	 */
+	for (i = 0; i < bmp->db_agwidth; i++, ti++) {
+		/* is there sufficient free space ?
+		 */
+		if (l2nb > dcp->stree[ti])
+			continue;
+
+		/* sufficient free space found in a subtree. now search down
+		 * the subtree to find the leftmost leaf that describes this
+		 * free space.
+		 */
+		for (k = bmp->db_agheight; k > 0; k--) {
+			for (n = 0, m = (ti << 2) + 1; n < 4; n++) {
+				if (l2nb <= dcp->stree[m + n]) {
+					ti = m + n;
+					break;
+				}
+			}
+			if (n == 4) {
+				jfs_error(bmp->db_ipbmap->i_sb,
+					  "failed descending stree\n");
+				release_metapage(mp);
+				return -EIO;
+			}
+		}
+
+		/* determine the block number within the file system
+		 * that corresponds to this leaf.
+		 */
+		if (bmp->db_aglevel == 2)
+			blkno = 0;
+		else if (bmp->db_aglevel == 1)
+			blkno &= ~(MAXL1SIZE - 1);
+		else		/* bmp->db_aglevel == 0 */
+			blkno &= ~(MAXL0SIZE - 1);
+
+		blkno +=
+		    ((s64) (ti - le32_to_cpu(dcp->leafidx))) << budmin;
+
+		/* release the buffer in preparation for going down
+		 * the next level of dmap control pages.
+		 */
+		release_metapage(mp);
+
+		/* check if we need to continue to search down the lower
+		 * level dmap control pages.  we need to if the number of
+		 * blocks required is less than maximum number of blocks
+		 * described at the next lower level.
+		 */
+		if (l2nb < budmin) {
+
+			/* search the lower level dmap control pages to get
+			 * the starting block number of the dmap that
+			 * contains or starts off the free space.
+			 */
+			if ((rc =
+			     dbFindCtl(bmp, l2nb, bmp->db_aglevel - 1,
+				       &blkno))) {
+				if (rc == -ENOSPC) {
+					jfs_error(bmp->db_ipbmap->i_sb,
+						  "control page inconsistent\n");
+					return -EIO;
+				}
+				return (rc);
+			}
+		}
+
+		/* allocate the blocks.
+		 */
+		rc = dbAllocCtl(bmp, nblocks, l2nb, blkno, results);
+		if (rc == -ENOSPC) {
+			jfs_error(bmp->db_ipbmap->i_sb,
+				  "unable to allocate blocks\n");
+			rc = -EIO;
+		}
+		return (rc);
+	}
+
+	/* no space in the allocation group.  release the buffer and
+	 * return -ENOSPC.
+	 */
+	release_metapage(mp);
+
+	return -ENOSPC;
+}
+
+
+/*
+ * NAME:	dbAllocAny()
+ *
+ * FUNCTION:	attempt to allocate the specified number of contiguous
+ *		free blocks anywhere in the file system.
+ *
+ *		dbAllocAny() attempts to find the sufficient free space by
+ *		searching down the dmap control pages, starting with the
+ *		highest level (i.e. L0, L1, L2) control page.  if free space
+ *		large enough to satisfy the desired free space is found, the
+ *		desired free space is allocated.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	nblocks	 -  actual number of contiguous free blocks desired.
+ *	l2nb	 -  log2 number of contiguous free blocks desired.
+ *	results	-  on successful return, set to the starting block number
+ *		   of the newly allocated range.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ *
+ * serialization: IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static int dbAllocAny(struct bmap * bmp, s64 nblocks, int l2nb, s64 * results)
+{
+	int rc;
+	s64 blkno = 0;
+
+	/* starting with the top level dmap control page, search
+	 * down the dmap control levels for sufficient free space.
+	 * if free space is found, dbFindCtl() returns the starting
+	 * block number of the dmap that contains or starts off the
+	 * range of free space.
+	 */
+	if ((rc = dbFindCtl(bmp, l2nb, bmp->db_maxlevel, &blkno)))
+		return (rc);
+
+	/* allocate the blocks.
+	 */
+	rc = dbAllocCtl(bmp, nblocks, l2nb, blkno, results);
+	if (rc == -ENOSPC) {
+		jfs_error(bmp->db_ipbmap->i_sb, "unable to allocate blocks\n");
+		return -EIO;
+	}
+	return (rc);
+}
+
+
+/*
+ * NAME:	dbDiscardAG()
+ *
+ * FUNCTION:	attempt to discard (TRIM) all free blocks of specific AG
+ *
+ *		algorithm:
+ *		1) allocate blocks, as large as possible and save them
+ *		   while holding IWRITE_LOCK on ipbmap
+ *		2) trim all these saved block/length values
+ *		3) mark the blocks free again
+ *
+ *		benefit:
+ *		- we work only on one ag at some time, minimizing how long we
+ *		  need to lock ipbmap
+ *		- reading / writing the fs is possible most time, even on
+ *		  trimming
+ *
+ *		downside:
+ *		- we write two times to the dmapctl and dmap pages
+ *		- but for me, this seems the best way, better ideas?
+ *		/TR 2012
+ *
+ * PARAMETERS:
+ *	ip	- pointer to in-core inode
+ *	agno	- ag to trim
+ *	minlen	- minimum value of contiguous blocks
+ *
+ * RETURN VALUES:
+ *	s64	- actual number of blocks trimmed
+ */
+s64 dbDiscardAG(struct inode *ip, int agno, s64 minlen)
+{
+	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
+	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
+	s64 nblocks, blkno;
+	u64 trimmed = 0;
+	int rc, l2nb;
+	struct super_block *sb = ipbmap->i_sb;
+
+	struct range2trim {
+		u64 blkno;
+		u64 nblocks;
+	} *totrim, *tt;
+
+	/* max blkno / nblocks pairs to trim */
+	int count = 0, range_cnt;
+	u64 max_ranges;
+
+	/* prevent others from writing new stuff here, while trimming */
+	IWRITE_LOCK(ipbmap, RDWRLOCK_DMAP);
+
+	nblocks = bmp->db_agfree[agno];
+	max_ranges = nblocks;
+	do_div(max_ranges, minlen);
+	range_cnt = min_t(u64, max_ranges + 1, 32 * 1024);
+	totrim = kmalloc_array(range_cnt, sizeof(struct range2trim), GFP_NOFS);
+	if (totrim == NULL) {
+		jfs_error(bmp->db_ipbmap->i_sb, "no memory for trim array\n");
+		IWRITE_UNLOCK(ipbmap);
+		return 0;
+	}
+
+	tt = totrim;
+	while (nblocks >= minlen) {
+		l2nb = BLKSTOL2(nblocks);
+
+		/* 0 = okay, -EIO = fatal, -ENOSPC -> try smaller block */
+		rc = dbAllocAG(bmp, agno, nblocks, l2nb, &blkno);
+		if (rc == 0) {
+			tt->blkno = blkno;
+			tt->nblocks = nblocks;
+			tt++; count++;
+
+			/* the whole ag is free, trim now */
+			if (bmp->db_agfree[agno] == 0)
+				break;
+
+			/* give a hint for the next while */
+			nblocks = bmp->db_agfree[agno];
+			continue;
+		} else if (rc == -ENOSPC) {
+			/* search for next smaller log2 block */
+			l2nb = BLKSTOL2(nblocks) - 1;
+			nblocks = 1LL << l2nb;
+		} else {
+			/* Trim any already allocated blocks */
+			jfs_error(bmp->db_ipbmap->i_sb, "-EIO\n");
+			break;
+		}
+
+		/* check, if our trim array is full */
+		if (unlikely(count >= range_cnt - 1))
+			break;
+	}
+	IWRITE_UNLOCK(ipbmap);
+
+	tt->nblocks = 0; /* mark the current end */
+	for (tt = totrim; tt->nblocks != 0; tt++) {
+		/* when mounted with online discard, dbFree() will
+		 * call jfs_issue_discard() itself */
+		if (!(JFS_SBI(sb)->flag & JFS_DISCARD))
+			jfs_issue_discard(ip, tt->blkno, tt->nblocks);
+		dbFree(ip, tt->blkno, tt->nblocks);
+		trimmed += tt->nblocks;
+	}
+	kfree(totrim);
+
+	return trimmed;
+}
+
+/*
+ * NAME:	dbFindCtl()
+ *
+ * FUNCTION:	starting at a specified dmap control page level and block
+ *		number, search down the dmap control levels for a range of
+ *		contiguous free blocks large enough to satisfy an allocation
+ *		request for the specified number of free blocks.
+ *
+ *		if sufficient contiguous free blocks are found, this routine
+ *		returns the starting block number within a dmap page that
+ *		contains or starts a range of contiqious free blocks that
+ *		is sufficient in size.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	level	-  starting dmap control page level.
+ *	l2nb	-  log2 number of contiguous free blocks desired.
+ *	*blkno	-  on entry, starting block number for conducting the search.
+ *		   on successful return, the first block within a dmap page
+ *		   that contains or starts a range of contiguous free blocks.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ *
+ * serialization: IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static int dbFindCtl(struct bmap * bmp, int l2nb, int level, s64 * blkno)
+{
+	int rc, leafidx, lev;
+	s64 b, lblkno;
+	struct dmapctl *dcp;
+	int budmin;
+	struct metapage *mp;
+
+	/* starting at the specified dmap control page level and block
+	 * number, search down the dmap control levels for the starting
+	 * block number of a dmap page that contains or starts off
+	 * sufficient free blocks.
+	 */
+	for (lev = level, b = *blkno; lev >= 0; lev--) {
+		/* get the buffer of the dmap control page for the block
+		 * number and level (i.e. L0, L1, L2).
+		 */
+		lblkno = BLKTOCTL(b, bmp->db_l2nbperpage, lev);
+		mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0);
+		if (mp == NULL)
+			return -EIO;
+		dcp = (struct dmapctl *) mp->data;
+		budmin = dcp->budmin;
+
+		if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) {
+			jfs_error(bmp->db_ipbmap->i_sb,
+				  "Corrupt dmapctl page\n");
+			release_metapage(mp);
+			return -EIO;
+		}
+
+		/* search the tree within the dmap control page for
+		 * sufficient free space.  if sufficient free space is found,
+		 * dbFindLeaf() returns the index of the leaf at which
+		 * free space was found.
+		 */
+		rc = dbFindLeaf((dmtree_t *) dcp, l2nb, &leafidx, true);
+
+		/* release the buffer.
+		 */
+		release_metapage(mp);
+
+		/* space found ?
+		 */
+		if (rc) {
+			if (lev != level) {
+				jfs_error(bmp->db_ipbmap->i_sb,
+					  "dmap inconsistent\n");
+				return -EIO;
+			}
+			return -ENOSPC;
+		}
+
+		/* adjust the block number to reflect the location within
+		 * the dmap control page (i.e. the leaf) at which free
+		 * space was found.
+		 */
+		b += (((s64) leafidx) << budmin);
+
+		/* we stop the search at this dmap control page level if
+		 * the number of blocks required is greater than or equal
+		 * to the maximum number of blocks described at the next
+		 * (lower) level.
+		 */
+		if (l2nb >= budmin)
+			break;
+	}
+
+	*blkno = b;
+	return (0);
+}
+
+
+/*
+ * NAME:	dbAllocCtl()
+ *
+ * FUNCTION:	attempt to allocate a specified number of contiguous
+ *		blocks starting within a specific dmap.
+ *
+ *		this routine is called by higher level routines that search
+ *		the dmap control pages above the actual dmaps for contiguous
+ *		free space.  the result of successful searches by these
+ *		routines are the starting block numbers within dmaps, with
+ *		the dmaps themselves containing the desired contiguous free
+ *		space or starting a contiguous free space of desired size
+ *		that is made up of the blocks of one or more dmaps. these
+ *		calls should not fail due to insufficent resources.
+ *
+ *		this routine is called in some cases where it is not known
+ *		whether it will fail due to insufficient resources.  more
+ *		specifically, this occurs when allocating from an allocation
+ *		group whose size is equal to the number of blocks per dmap.
+ *		in this case, the dmap control pages are not examined prior
+ *		to calling this routine (to save pathlength) and the call
+ *		might fail.
+ *
+ *		for a request size that fits within a dmap, this routine relies
+ *		upon the dmap's dmtree to find the requested contiguous free
+ *		space.  for request sizes that are larger than a dmap, the
+ *		requested free space will start at the first block of the
+ *		first dmap (i.e. blkno).
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	nblocks	 -  actual number of contiguous free blocks to allocate.
+ *	l2nb	 -  log2 number of contiguous free blocks to allocate.
+ *	blkno	 -  starting block number of the dmap to start the allocation
+ *		    from.
+ *	results	-  on successful return, set to the starting block number
+ *		   of the newly allocated range.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ *
+ * serialization: IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static int
+dbAllocCtl(struct bmap * bmp, s64 nblocks, int l2nb, s64 blkno, s64 * results)
+{
+	int rc, nb;
+	s64 b, lblkno, n;
+	struct metapage *mp;
+	struct dmap *dp;
+
+	/* check if the allocation request is confined to a single dmap.
+	 */
+	if (l2nb <= L2BPERDMAP) {
+		/* get the buffer for the dmap.
+		 */
+		lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage);
+		mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0);
+		if (mp == NULL)
+			return -EIO;
+		dp = (struct dmap *) mp->data;
+
+		/* try to allocate the blocks.
+		 */
+		rc = dbAllocDmapLev(bmp, dp, (int) nblocks, l2nb, results);
+		if (rc == 0)
+			mark_metapage_dirty(mp);
+
+		release_metapage(mp);
+
+		return (rc);
+	}
+
+	/* allocation request involving multiple dmaps. it must start on
+	 * a dmap boundary.
+	 */
+	assert((blkno & (BPERDMAP - 1)) == 0);
+
+	/* allocate the blocks dmap by dmap.
+	 */
+	for (n = nblocks, b = blkno; n > 0; n -= nb, b += nb) {
+		/* get the buffer for the dmap.
+		 */
+		lblkno = BLKTODMAP(b, bmp->db_l2nbperpage);
+		mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0);
+		if (mp == NULL) {
+			rc = -EIO;
+			goto backout;
+		}
+		dp = (struct dmap *) mp->data;
+
+		/* the dmap better be all free.
+		 */
+		if (dp->tree.stree[ROOT] != L2BPERDMAP) {
+			release_metapage(mp);
+			jfs_error(bmp->db_ipbmap->i_sb,
+				  "the dmap is not all free\n");
+			rc = -EIO;
+			goto backout;
+		}
+
+		/* determine how many blocks to allocate from this dmap.
+		 */
+		nb = min_t(s64, n, BPERDMAP);
+
+		/* allocate the blocks from the dmap.
+		 */
+		if ((rc = dbAllocDmap(bmp, dp, b, nb))) {
+			release_metapage(mp);
+			goto backout;
+		}
+
+		/* write the buffer.
+		 */
+		write_metapage(mp);
+	}
+
+	/* set the results (starting block number) and return.
+	 */
+	*results = blkno;
+	return (0);
+
+	/* something failed in handling an allocation request involving
+	 * multiple dmaps.  we'll try to clean up by backing out any
+	 * allocation that has already happened for this request.  if
+	 * we fail in backing out the allocation, we'll mark the file
+	 * system to indicate that blocks have been leaked.
+	 */
+      backout:
+
+	/* try to backout the allocations dmap by dmap.
+	 */
+	for (n = nblocks - n, b = blkno; n > 0;
+	     n -= BPERDMAP, b += BPERDMAP) {
+		/* get the buffer for this dmap.
+		 */
+		lblkno = BLKTODMAP(b, bmp->db_l2nbperpage);
+		mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0);
+		if (mp == NULL) {
+			/* could not back out.  mark the file system
+			 * to indicate that we have leaked blocks.
+			 */
+			jfs_error(bmp->db_ipbmap->i_sb,
+				  "I/O Error: Block Leakage\n");
+			continue;
+		}
+		dp = (struct dmap *) mp->data;
+
+		/* free the blocks is this dmap.
+		 */
+		if (dbFreeDmap(bmp, dp, b, BPERDMAP)) {
+			/* could not back out.  mark the file system
+			 * to indicate that we have leaked blocks.
+			 */
+			release_metapage(mp);
+			jfs_error(bmp->db_ipbmap->i_sb, "Block Leakage\n");
+			continue;
+		}
+
+		/* write the buffer.
+		 */
+		write_metapage(mp);
+	}
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	dbAllocDmapLev()
+ *
+ * FUNCTION:	attempt to allocate a specified number of contiguous blocks
+ *		from a specified dmap.
+ *
+ *		this routine checks if the contiguous blocks are available.
+ *		if so, nblocks of blocks are allocated; otherwise, ENOSPC is
+ *		returned.
+ *
+ * PARAMETERS:
+ *	mp	-  pointer to bmap descriptor
+ *	dp	-  pointer to dmap to attempt to allocate blocks from.
+ *	l2nb	-  log2 number of contiguous block desired.
+ *	nblocks	-  actual number of contiguous block desired.
+ *	results	-  on successful return, set to the starting block number
+ *		   of the newly allocated range.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient disk resources
+ *	-EIO	- i/o error
+ *
+ * serialization: IREAD_LOCK(ipbmap), e.g., from dbAlloc(), or
+ *	IWRITE_LOCK(ipbmap), e.g., dbAllocCtl(), held on entry/exit;
+ */
+static int
+dbAllocDmapLev(struct bmap * bmp,
+	       struct dmap * dp, int nblocks, int l2nb, s64 * results)
+{
+	s64 blkno;
+	int leafidx, rc;
+
+	/* can't be more than a dmaps worth of blocks */
+	assert(l2nb <= L2BPERDMAP);
+
+	/* search the tree within the dmap page for sufficient
+	 * free space.  if sufficient free space is found, dbFindLeaf()
+	 * returns the index of the leaf at which free space was found.
+	 */
+	if (dbFindLeaf((dmtree_t *) &dp->tree, l2nb, &leafidx, false))
+		return -ENOSPC;
+
+	if (leafidx < 0)
+		return -EIO;
+
+	/* determine the block number within the file system corresponding
+	 * to the leaf at which free space was found.
+	 */
+	blkno = le64_to_cpu(dp->start) + (leafidx << L2DBWORD);
+
+	/* if not all bits of the dmap word are free, get the starting
+	 * bit number within the dmap word of the required string of free
+	 * bits and adjust the block number with this value.
+	 */
+	if (dp->tree.stree[leafidx + LEAFIND] < BUDMIN)
+		blkno += dbFindBits(le32_to_cpu(dp->wmap[leafidx]), l2nb);
+
+	/* allocate the blocks */
+	if ((rc = dbAllocDmap(bmp, dp, blkno, nblocks)) == 0)
+		*results = blkno;
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	dbAllocDmap()
+ *
+ * FUNCTION:	adjust the disk allocation map to reflect the allocation
+ *		of a specified block range within a dmap.
+ *
+ *		this routine allocates the specified blocks from the dmap
+ *		through a call to dbAllocBits(). if the allocation of the
+ *		block range causes the maximum string of free blocks within
+ *		the dmap to change (i.e. the value of the root of the dmap's
+ *		dmtree), this routine will cause this change to be reflected
+ *		up through the appropriate levels of the dmap control pages
+ *		by a call to dbAdjCtl() for the L0 dmap control page that
+ *		covers this dmap.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	dp	-  pointer to dmap to allocate the block range from.
+ *	blkno	-  starting block number of the block to be allocated.
+ *	nblocks	-  number of blocks to be allocated.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error
+ *
+ * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static int dbAllocDmap(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		       int nblocks)
+{
+	s8 oldroot;
+	int rc;
+
+	/* save the current value of the root (i.e. maximum free string)
+	 * of the dmap tree.
+	 */
+	oldroot = dp->tree.stree[ROOT];
+
+	/* allocate the specified (blocks) bits */
+	dbAllocBits(bmp, dp, blkno, nblocks);
+
+	/* if the root has not changed, done. */
+	if (dp->tree.stree[ROOT] == oldroot)
+		return (0);
+
+	/* root changed. bubble the change up to the dmap control pages.
+	 * if the adjustment of the upper level control pages fails,
+	 * backout the bit allocation (thus making everything consistent).
+	 */
+	if ((rc = dbAdjCtl(bmp, blkno, dp->tree.stree[ROOT], 1, 0)))
+		dbFreeBits(bmp, dp, blkno, nblocks);
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	dbFreeDmap()
+ *
+ * FUNCTION:	adjust the disk allocation map to reflect the allocation
+ *		of a specified block range within a dmap.
+ *
+ *		this routine frees the specified blocks from the dmap through
+ *		a call to dbFreeBits(). if the deallocation of the block range
+ *		causes the maximum string of free blocks within the dmap to
+ *		change (i.e. the value of the root of the dmap's dmtree), this
+ *		routine will cause this change to be reflected up through the
+ *		appropriate levels of the dmap control pages by a call to
+ *		dbAdjCtl() for the L0 dmap control page that covers this dmap.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	dp	-  pointer to dmap to free the block range from.
+ *	blkno	-  starting block number of the block to be freed.
+ *	nblocks	-  number of blocks to be freed.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error
+ *
+ * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static int dbFreeDmap(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		      int nblocks)
+{
+	s8 oldroot;
+	int rc = 0, word;
+
+	/* save the current value of the root (i.e. maximum free string)
+	 * of the dmap tree.
+	 */
+	oldroot = dp->tree.stree[ROOT];
+
+	/* free the specified (blocks) bits */
+	rc = dbFreeBits(bmp, dp, blkno, nblocks);
+
+	/* if error or the root has not changed, done. */
+	if (rc || (dp->tree.stree[ROOT] == oldroot))
+		return (rc);
+
+	/* root changed. bubble the change up to the dmap control pages.
+	 * if the adjustment of the upper level control pages fails,
+	 * backout the deallocation.
+	 */
+	if ((rc = dbAdjCtl(bmp, blkno, dp->tree.stree[ROOT], 0, 0))) {
+		word = (blkno & (BPERDMAP - 1)) >> L2DBWORD;
+
+		/* as part of backing out the deallocation, we will have
+		 * to back split the dmap tree if the deallocation caused
+		 * the freed blocks to become part of a larger binary buddy
+		 * system.
+		 */
+		if (dp->tree.stree[word] == NOFREE)
+			dbBackSplit((dmtree_t *) & dp->tree, word);
+
+		dbAllocBits(bmp, dp, blkno, nblocks);
+	}
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	dbAllocBits()
+ *
+ * FUNCTION:	allocate a specified block range from a dmap.
+ *
+ *		this routine updates the dmap to reflect the working
+ *		state allocation of the specified block range. it directly
+ *		updates the bits of the working map and causes the adjustment
+ *		of the binary buddy system described by the dmap's dmtree
+ *		leaves to reflect the bits allocated.  it also causes the
+ *		dmap's dmtree, as a whole, to reflect the allocated range.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	dp	-  pointer to dmap to allocate bits from.
+ *	blkno	-  starting block number of the bits to be allocated.
+ *	nblocks	-  number of bits to be allocated.
+ *
+ * RETURN VALUES: none
+ *
+ * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static void dbAllocBits(struct bmap * bmp, struct dmap * dp, s64 blkno,
+			int nblocks)
+{
+	int dbitno, word, rembits, nb, nwords, wbitno, nw, agno;
+	dmtree_t *tp = (dmtree_t *) & dp->tree;
+	int size;
+	s8 *leaf;
+
+	/* pick up a pointer to the leaves of the dmap tree */
+	leaf = dp->tree.stree + LEAFIND;
+
+	/* determine the bit number and word within the dmap of the
+	 * starting block.
+	 */
+	dbitno = blkno & (BPERDMAP - 1);
+	word = dbitno >> L2DBWORD;
+
+	/* block range better be within the dmap */
+	assert(dbitno + nblocks <= BPERDMAP);
+
+	/* allocate the bits of the dmap's words corresponding to the block
+	 * range. not all bits of the first and last words may be contained
+	 * within the block range.  if this is the case, we'll work against
+	 * those words (i.e. partial first and/or last) on an individual basis
+	 * (a single pass), allocating the bits of interest by hand and
+	 * updating the leaf corresponding to the dmap word. a single pass
+	 * will be used for all dmap words fully contained within the
+	 * specified range.  within this pass, the bits of all fully contained
+	 * dmap words will be marked as free in a single shot and the leaves
+	 * will be updated. a single leaf may describe the free space of
+	 * multiple dmap words, so we may update only a subset of the actual
+	 * leaves corresponding to the dmap words of the block range.
+	 */
+	for (rembits = nblocks; rembits > 0; rembits -= nb, dbitno += nb) {
+		/* determine the bit number within the word and
+		 * the number of bits within the word.
+		 */
+		wbitno = dbitno & (DBWORD - 1);
+		nb = min(rembits, DBWORD - wbitno);
+
+		/* check if only part of a word is to be allocated.
+		 */
+		if (nb < DBWORD) {
+			/* allocate (set to 1) the appropriate bits within
+			 * this dmap word.
+			 */
+			dp->wmap[word] |= cpu_to_le32(ONES << (DBWORD - nb)
+						      >> wbitno);
+
+			/* update the leaf for this dmap word. in addition
+			 * to setting the leaf value to the binary buddy max
+			 * of the updated dmap word, dbSplit() will split
+			 * the binary system of the leaves if need be.
+			 */
+			dbSplit(tp, word, BUDMIN,
+				dbMaxBud((u8 *) & dp->wmap[word]));
+
+			word += 1;
+		} else {
+			/* one or more dmap words are fully contained
+			 * within the block range.  determine how many
+			 * words and allocate (set to 1) the bits of these
+			 * words.
+			 */
+			nwords = rembits >> L2DBWORD;
+			memset(&dp->wmap[word], (int) ONES, nwords * 4);
+
+			/* determine how many bits.
+			 */
+			nb = nwords << L2DBWORD;
+
+			/* now update the appropriate leaves to reflect
+			 * the allocated words.
+			 */
+			for (; nwords > 0; nwords -= nw) {
+				if (leaf[word] < BUDMIN) {
+					jfs_error(bmp->db_ipbmap->i_sb,
+						  "leaf page corrupt\n");
+					break;
+				}
+
+				/* determine what the leaf value should be
+				 * updated to as the minimum of the l2 number
+				 * of bits being allocated and the l2 number
+				 * of bits currently described by this leaf.
+				 */
+				size = min_t(int, leaf[word],
+					     NLSTOL2BSZ(nwords));
+
+				/* update the leaf to reflect the allocation.
+				 * in addition to setting the leaf value to
+				 * NOFREE, dbSplit() will split the binary
+				 * system of the leaves to reflect the current
+				 * allocation (size).
+				 */
+				dbSplit(tp, word, size, NOFREE);
+
+				/* get the number of dmap words handled */
+				nw = BUDSIZE(size, BUDMIN);
+				word += nw;
+			}
+		}
+	}
+
+	/* update the free count for this dmap */
+	le32_add_cpu(&dp->nfree, -nblocks);
+
+	BMAP_LOCK(bmp);
+
+	/* if this allocation group is completely free,
+	 * update the maximum allocation group number if this allocation
+	 * group is the new max.
+	 */
+	agno = blkno >> bmp->db_agl2size;
+	if (agno > bmp->db_maxag)
+		bmp->db_maxag = agno;
+
+	/* update the free count for the allocation group and map */
+	bmp->db_agfree[agno] -= nblocks;
+	bmp->db_nfree -= nblocks;
+
+	BMAP_UNLOCK(bmp);
+}
+
+
+/*
+ * NAME:	dbFreeBits()
+ *
+ * FUNCTION:	free a specified block range from a dmap.
+ *
+ *		this routine updates the dmap to reflect the working
+ *		state allocation of the specified block range. it directly
+ *		updates the bits of the working map and causes the adjustment
+ *		of the binary buddy system described by the dmap's dmtree
+ *		leaves to reflect the bits freed.  it also causes the dmap's
+ *		dmtree, as a whole, to reflect the deallocated range.
+ *
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	dp	-  pointer to dmap to free bits from.
+ *	blkno	-  starting block number of the bits to be freed.
+ *	nblocks	-  number of bits to be freed.
+ *
+ * RETURN VALUES: 0 for success
+ *
+ * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static int dbFreeBits(struct bmap * bmp, struct dmap * dp, s64 blkno,
+		       int nblocks)
+{
+	int dbitno, word, rembits, nb, nwords, wbitno, nw, agno;
+	dmtree_t *tp = (dmtree_t *) & dp->tree;
+	int rc = 0;
+	int size;
+
+	/* determine the bit number and word within the dmap of the
+	 * starting block.
+	 */
+	dbitno = blkno & (BPERDMAP - 1);
+	word = dbitno >> L2DBWORD;
+
+	/* block range better be within the dmap.
+	 */
+	assert(dbitno + nblocks <= BPERDMAP);
+
+	/* free the bits of the dmaps words corresponding to the block range.
+	 * not all bits of the first and last words may be contained within
+	 * the block range.  if this is the case, we'll work against those
+	 * words (i.e. partial first and/or last) on an individual basis
+	 * (a single pass), freeing the bits of interest by hand and updating
+	 * the leaf corresponding to the dmap word. a single pass will be used
+	 * for all dmap words fully contained within the specified range.
+	 * within this pass, the bits of all fully contained dmap words will
+	 * be marked as free in a single shot and the leaves will be updated. a
+	 * single leaf may describe the free space of multiple dmap words,
+	 * so we may update only a subset of the actual leaves corresponding
+	 * to the dmap words of the block range.
+	 *
+	 * dbJoin() is used to update leaf values and will join the binary
+	 * buddy system of the leaves if the new leaf values indicate this
+	 * should be done.
+	 */
+	for (rembits = nblocks; rembits > 0; rembits -= nb, dbitno += nb) {
+		/* determine the bit number within the word and
+		 * the number of bits within the word.
+		 */
+		wbitno = dbitno & (DBWORD - 1);
+		nb = min(rembits, DBWORD - wbitno);
+
+		/* check if only part of a word is to be freed.
+		 */
+		if (nb < DBWORD) {
+			/* free (zero) the appropriate bits within this
+			 * dmap word.
+			 */
+			dp->wmap[word] &=
+			    cpu_to_le32(~(ONES << (DBWORD - nb)
+					  >> wbitno));
+
+			/* update the leaf for this dmap word.
+			 */
+			rc = dbJoin(tp, word,
+				    dbMaxBud((u8 *) & dp->wmap[word]));
+			if (rc)
+				return rc;
+
+			word += 1;
+		} else {
+			/* one or more dmap words are fully contained
+			 * within the block range.  determine how many
+			 * words and free (zero) the bits of these words.
+			 */
+			nwords = rembits >> L2DBWORD;
+			memset(&dp->wmap[word], 0, nwords * 4);
+
+			/* determine how many bits.
+			 */
+			nb = nwords << L2DBWORD;
+
+			/* now update the appropriate leaves to reflect
+			 * the freed words.
+			 */
+			for (; nwords > 0; nwords -= nw) {
+				/* determine what the leaf value should be
+				 * updated to as the minimum of the l2 number
+				 * of bits being freed and the l2 (max) number
+				 * of bits that can be described by this leaf.
+				 */
+				size =
+				    min(LITOL2BSZ
+					(word, L2LPERDMAP, BUDMIN),
+					NLSTOL2BSZ(nwords));
+
+				/* update the leaf.
+				 */
+				rc = dbJoin(tp, word, size);
+				if (rc)
+					return rc;
+
+				/* get the number of dmap words handled.
+				 */
+				nw = BUDSIZE(size, BUDMIN);
+				word += nw;
+			}
+		}
+	}
+
+	/* update the free count for this dmap.
+	 */
+	le32_add_cpu(&dp->nfree, nblocks);
+
+	BMAP_LOCK(bmp);
+
+	/* update the free count for the allocation group and
+	 * map.
+	 */
+	agno = blkno >> bmp->db_agl2size;
+	bmp->db_nfree += nblocks;
+	bmp->db_agfree[agno] += nblocks;
+
+	/* check if this allocation group is not completely free and
+	 * if it is currently the maximum (rightmost) allocation group.
+	 * if so, establish the new maximum allocation group number by
+	 * searching left for the first allocation group with allocation.
+	 */
+	if ((bmp->db_agfree[agno] == bmp->db_agsize && agno == bmp->db_maxag) ||
+	    (agno == bmp->db_numag - 1 &&
+	     bmp->db_agfree[agno] == (bmp-> db_mapsize & (BPERDMAP - 1)))) {
+		while (bmp->db_maxag > 0) {
+			bmp->db_maxag -= 1;
+			if (bmp->db_agfree[bmp->db_maxag] !=
+			    bmp->db_agsize)
+				break;
+		}
+
+		/* re-establish the allocation group preference if the
+		 * current preference is right of the maximum allocation
+		 * group.
+		 */
+		if (bmp->db_agpref > bmp->db_maxag)
+			bmp->db_agpref = bmp->db_maxag;
+	}
+
+	BMAP_UNLOCK(bmp);
+
+	return 0;
+}
+
+
+/*
+ * NAME:	dbAdjCtl()
+ *
+ * FUNCTION:	adjust a dmap control page at a specified level to reflect
+ *		the change in a lower level dmap or dmap control page's
+ *		maximum string of free blocks (i.e. a change in the root
+ *		of the lower level object's dmtree) due to the allocation
+ *		or deallocation of a range of blocks with a single dmap.
+ *
+ *		on entry, this routine is provided with the new value of
+ *		the lower level dmap or dmap control page root and the
+ *		starting block number of the block range whose allocation
+ *		or deallocation resulted in the root change.  this range
+ *		is respresented by a single leaf of the current dmapctl
+ *		and the leaf will be updated with this value, possibly
+ *		causing a binary buddy system within the leaves to be
+ *		split or joined.  the update may also cause the dmapctl's
+ *		dmtree to be updated.
+ *
+ *		if the adjustment of the dmap control page, itself, causes its
+ *		root to change, this change will be bubbled up to the next dmap
+ *		control level by a recursive call to this routine, specifying
+ *		the new root value and the next dmap control page level to
+ *		be adjusted.
+ * PARAMETERS:
+ *	bmp	-  pointer to bmap descriptor
+ *	blkno	-  the first block of a block range within a dmap.  it is
+ *		   the allocation or deallocation of this block range that
+ *		   requires the dmap control page to be adjusted.
+ *	newval	-  the new value of the lower level dmap or dmap control
+ *		   page root.
+ *	alloc	-  'true' if adjustment is due to an allocation.
+ *	level	-  current level of dmap control page (i.e. L0, L1, L2) to
+ *		   be adjusted.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error
+ *
+ * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static int
+dbAdjCtl(struct bmap * bmp, s64 blkno, int newval, int alloc, int level)
+{
+	struct metapage *mp;
+	s8 oldroot;
+	int oldval;
+	s64 lblkno;
+	struct dmapctl *dcp;
+	int rc, leafno, ti;
+
+	/* get the buffer for the dmap control page for the specified
+	 * block number and control page level.
+	 */
+	lblkno = BLKTOCTL(blkno, bmp->db_l2nbperpage, level);
+	mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0);
+	if (mp == NULL)
+		return -EIO;
+	dcp = (struct dmapctl *) mp->data;
+
+	if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) {
+		jfs_error(bmp->db_ipbmap->i_sb, "Corrupt dmapctl page\n");
+		release_metapage(mp);
+		return -EIO;
+	}
+
+	/* determine the leaf number corresponding to the block and
+	 * the index within the dmap control tree.
+	 */
+	leafno = BLKTOCTLLEAF(blkno, dcp->budmin);
+	ti = leafno + le32_to_cpu(dcp->leafidx);
+
+	/* save the current leaf value and the current root level (i.e.
+	 * maximum l2 free string described by this dmapctl).
+	 */
+	oldval = dcp->stree[ti];
+	oldroot = dcp->stree[ROOT];
+
+	/* check if this is a control page update for an allocation.
+	 * if so, update the leaf to reflect the new leaf value using
+	 * dbSplit(); otherwise (deallocation), use dbJoin() to update
+	 * the leaf with the new value.  in addition to updating the
+	 * leaf, dbSplit() will also split the binary buddy system of
+	 * the leaves, if required, and bubble new values within the
+	 * dmapctl tree, if required.  similarly, dbJoin() will join
+	 * the binary buddy system of leaves and bubble new values up
+	 * the dmapctl tree as required by the new leaf value.
+	 */
+	if (alloc) {
+		/* check if we are in the middle of a binary buddy
+		 * system.  this happens when we are performing the
+		 * first allocation out of an allocation group that
+		 * is part (not the first part) of a larger binary
+		 * buddy system.  if we are in the middle, back split
+		 * the system prior to calling dbSplit() which assumes
+		 * that it is at the front of a binary buddy system.
+		 */
+		if (oldval == NOFREE) {
+			rc = dbBackSplit((dmtree_t *) dcp, leafno);
+			if (rc) {
+				release_metapage(mp);
+				return rc;
+			}
+			oldval = dcp->stree[ti];
+		}
+		dbSplit((dmtree_t *) dcp, leafno, dcp->budmin, newval);
+	} else {
+		rc = dbJoin((dmtree_t *) dcp, leafno, newval);
+		if (rc) {
+			release_metapage(mp);
+			return rc;
+		}
+	}
+
+	/* check if the root of the current dmap control page changed due
+	 * to the update and if the current dmap control page is not at
+	 * the current top level (i.e. L0, L1, L2) of the map.  if so (i.e.
+	 * root changed and this is not the top level), call this routine
+	 * again (recursion) for the next higher level of the mapping to
+	 * reflect the change in root for the current dmap control page.
+	 */
+	if (dcp->stree[ROOT] != oldroot) {
+		/* are we below the top level of the map.  if so,
+		 * bubble the root up to the next higher level.
+		 */
+		if (level < bmp->db_maxlevel) {
+			/* bubble up the new root of this dmap control page to
+			 * the next level.
+			 */
+			if ((rc =
+			     dbAdjCtl(bmp, blkno, dcp->stree[ROOT], alloc,
+				      level + 1))) {
+				/* something went wrong in bubbling up the new
+				 * root value, so backout the changes to the
+				 * current dmap control page.
+				 */
+				if (alloc) {
+					dbJoin((dmtree_t *) dcp, leafno,
+					       oldval);
+				} else {
+					/* the dbJoin() above might have
+					 * caused a larger binary buddy system
+					 * to form and we may now be in the
+					 * middle of it.  if this is the case,
+					 * back split the buddies.
+					 */
+					if (dcp->stree[ti] == NOFREE)
+						dbBackSplit((dmtree_t *)
+							    dcp, leafno);
+					dbSplit((dmtree_t *) dcp, leafno,
+						dcp->budmin, oldval);
+				}
+
+				/* release the buffer and return the error.
+				 */
+				release_metapage(mp);
+				return (rc);
+			}
+		} else {
+			/* we're at the top level of the map. update
+			 * the bmap control page to reflect the size
+			 * of the maximum free buddy system.
+			 */
+			assert(level == bmp->db_maxlevel);
+			if (bmp->db_maxfreebud != oldroot) {
+				jfs_error(bmp->db_ipbmap->i_sb,
+					  "the maximum free buddy is not the old root\n");
+			}
+			bmp->db_maxfreebud = dcp->stree[ROOT];
+		}
+	}
+
+	/* write the buffer.
+	 */
+	write_metapage(mp);
+
+	return (0);
+}
+
+
+/*
+ * NAME:	dbSplit()
+ *
+ * FUNCTION:	update the leaf of a dmtree with a new value, splitting
+ *		the leaf from the binary buddy system of the dmtree's
+ *		leaves, as required.
+ *
+ * PARAMETERS:
+ *	tp	- pointer to the tree containing the leaf.
+ *	leafno	- the number of the leaf to be updated.
+ *	splitsz	- the size the binary buddy system starting at the leaf
+ *		  must be split to, specified as the log2 number of blocks.
+ *	newval	- the new value for the leaf.
+ *
+ * RETURN VALUES: none
+ *
+ * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static void dbSplit(dmtree_t * tp, int leafno, int splitsz, int newval)
+{
+	int budsz;
+	int cursz;
+	s8 *leaf = tp->dmt_stree + le32_to_cpu(tp->dmt_leafidx);
+
+	/* check if the leaf needs to be split.
+	 */
+	if (leaf[leafno] > tp->dmt_budmin) {
+		/* the split occurs by cutting the buddy system in half
+		 * at the specified leaf until we reach the specified
+		 * size.  pick up the starting split size (current size
+		 * - 1 in l2) and the corresponding buddy size.
+		 */
+		cursz = leaf[leafno] - 1;
+		budsz = BUDSIZE(cursz, tp->dmt_budmin);
+
+		/* split until we reach the specified size.
+		 */
+		while (cursz >= splitsz) {
+			/* update the buddy's leaf with its new value.
+			 */
+			dbAdjTree(tp, leafno ^ budsz, cursz);
+
+			/* on to the next size and buddy.
+			 */
+			cursz -= 1;
+			budsz >>= 1;
+		}
+	}
+
+	/* adjust the dmap tree to reflect the specified leaf's new
+	 * value.
+	 */
+	dbAdjTree(tp, leafno, newval);
+}
+
+
+/*
+ * NAME:	dbBackSplit()
+ *
+ * FUNCTION:	back split the binary buddy system of dmtree leaves
+ *		that hold a specified leaf until the specified leaf
+ *		starts its own binary buddy system.
+ *
+ *		the allocators typically perform allocations at the start
+ *		of binary buddy systems and dbSplit() is used to accomplish
+ *		any required splits.  in some cases, however, allocation
+ *		may occur in the middle of a binary system and requires a
+ *		back split, with the split proceeding out from the middle of
+ *		the system (less efficient) rather than the start of the
+ *		system (more efficient).  the cases in which a back split
+ *		is required are rare and are limited to the first allocation
+ *		within an allocation group which is a part (not first part)
+ *		of a larger binary buddy system and a few exception cases
+ *		in which a previous join operation must be backed out.
+ *
+ * PARAMETERS:
+ *	tp	- pointer to the tree containing the leaf.
+ *	leafno	- the number of the leaf to be updated.
+ *
+ * RETURN VALUES: none
+ *
+ * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit;
+ */
+static int dbBackSplit(dmtree_t * tp, int leafno)
+{
+	int budsz, bud, w, bsz, size;
+	int cursz;
+	s8 *leaf = tp->dmt_stree + le32_to_cpu(tp->dmt_leafidx);
+
+	/* leaf should be part (not first part) of a binary
+	 * buddy system.
+	 */
+	assert(leaf[leafno] == NOFREE);
+
+	/* the back split is accomplished by iteratively finding the leaf
+	 * that starts the buddy system that contains the specified leaf and
+	 * splitting that system in two.  this iteration continues until
+	 * the specified leaf becomes the start of a buddy system.
+	 *
+	 * determine maximum possible l2 size for the specified leaf.
+	 */
+	size =
+	    LITOL2BSZ(leafno, le32_to_cpu(tp->dmt_l2nleafs),
+		      tp->dmt_budmin);
+
+	/* determine the number of leaves covered by this size.  this
+	 * is the buddy size that we will start with as we search for
+	 * the buddy system that contains the specified leaf.
+	 */
+	budsz = BUDSIZE(size, tp->dmt_budmin);
+
+	/* back split.
+	 */
+	while (leaf[leafno] == NOFREE) {
+		/* find the leftmost buddy leaf.
+		 */
+		for (w = leafno, bsz = budsz;; bsz <<= 1,
+		     w = (w < bud) ? w : bud) {
+			if (bsz >= le32_to_cpu(tp->dmt_nleafs)) {
+				jfs_err("JFS: block map error in dbBackSplit");
+				return -EIO;
+			}
+
+			/* determine the buddy.
+			 */
+			bud = w ^ bsz;
+
+			/* check if this buddy is the start of the system.
+			 */
+			if (leaf[bud] != NOFREE) {
+				/* split the leaf at the start of the
+				 * system in two.
+				 */
+				cursz = leaf[bud] - 1;
+				dbSplit(tp, bud, cursz, cursz);
+				break;
+			}
+		}
+	}
+
+	if (leaf[leafno] != size) {
+		jfs_err("JFS: wrong leaf value in dbBackSplit");
+		return -EIO;
+	}
+	return 0;
+}
+
+
+/*
+ * NAME:	dbJoin()
+ *
+ * FUNCTION:	update the leaf of a dmtree with a new value, joining
+ *		the leaf with other leaves of the dmtree into a multi-leaf
+ *		binary buddy system, as required.
+ *
+ * PARAMETERS:
+ *	tp	- pointer to the tree containing the leaf.
+ *	leafno	- the number of the leaf to be updated.
+ *	newval	- the new value for the leaf.
+ *
+ * RETURN VALUES: none
+ */
+static int dbJoin(dmtree_t * tp, int leafno, int newval)
+{
+	int budsz, buddy;
+	s8 *leaf;
+
+	/* can the new leaf value require a join with other leaves ?
+	 */
+	if (newval >= tp->dmt_budmin) {
+		/* pickup a pointer to the leaves of the tree.
+		 */
+		leaf = tp->dmt_stree + le32_to_cpu(tp->dmt_leafidx);
+
+		/* try to join the specified leaf into a large binary
+		 * buddy system.  the join proceeds by attempting to join
+		 * the specified leafno with its buddy (leaf) at new value.
+		 * if the join occurs, we attempt to join the left leaf
+		 * of the joined buddies with its buddy at new value + 1.
+		 * we continue to join until we find a buddy that cannot be
+		 * joined (does not have a value equal to the size of the
+		 * last join) or until all leaves have been joined into a
+		 * single system.
+		 *
+		 * get the buddy size (number of words covered) of
+		 * the new value.
+		 */
+		budsz = BUDSIZE(newval, tp->dmt_budmin);
+
+		/* try to join.
+		 */
+		while (budsz < le32_to_cpu(tp->dmt_nleafs)) {
+			/* get the buddy leaf.
+			 */
+			buddy = leafno ^ budsz;
+
+			/* if the leaf's new value is greater than its
+			 * buddy's value, we join no more.
+			 */
+			if (newval > leaf[buddy])
+				break;
+
+			/* It shouldn't be less */
+			if (newval < leaf[buddy])
+				return -EIO;
+
+			/* check which (leafno or buddy) is the left buddy.
+			 * the left buddy gets to claim the blocks resulting
+			 * from the join while the right gets to claim none.
+			 * the left buddy is also eligible to participate in
+			 * a join at the next higher level while the right
+			 * is not.
+			 *
+			 */
+			if (leafno < buddy) {
+				/* leafno is the left buddy.
+				 */
+				dbAdjTree(tp, buddy, NOFREE);
+			} else {
+				/* buddy is the left buddy and becomes
+				 * leafno.
+				 */
+				dbAdjTree(tp, leafno, NOFREE);
+				leafno = buddy;
+			}
+
+			/* on to try the next join.
+			 */
+			newval += 1;
+			budsz <<= 1;
+		}
+	}
+
+	/* update the leaf value.
+	 */
+	dbAdjTree(tp, leafno, newval);
+
+	return 0;
+}
+
+
+/*
+ * NAME:	dbAdjTree()
+ *
+ * FUNCTION:	update a leaf of a dmtree with a new value, adjusting
+ *		the dmtree, as required, to reflect the new leaf value.
+ *		the combination of any buddies must already be done before
+ *		this is called.
+ *
+ * PARAMETERS:
+ *	tp	- pointer to the tree to be adjusted.
+ *	leafno	- the number of the leaf to be updated.
+ *	newval	- the new value for the leaf.
+ *
+ * RETURN VALUES: none
+ */
+static void dbAdjTree(dmtree_t * tp, int leafno, int newval)
+{
+	int lp, pp, k;
+	int max;
+
+	/* pick up the index of the leaf for this leafno.
+	 */
+	lp = leafno + le32_to_cpu(tp->dmt_leafidx);
+
+	/* is the current value the same as the old value ?  if so,
+	 * there is nothing to do.
+	 */
+	if (tp->dmt_stree[lp] == newval)
+		return;
+
+	/* set the new value.
+	 */
+	tp->dmt_stree[lp] = newval;
+
+	/* bubble the new value up the tree as required.
+	 */
+	for (k = 0; k < le32_to_cpu(tp->dmt_height); k++) {
+		/* get the index of the first leaf of the 4 leaf
+		 * group containing the specified leaf (leafno).
+		 */
+		lp = ((lp - 1) & ~0x03) + 1;
+
+		/* get the index of the parent of this 4 leaf group.
+		 */
+		pp = (lp - 1) >> 2;
+
+		/* determine the maximum of the 4 leaves.
+		 */
+		max = TREEMAX(&tp->dmt_stree[lp]);
+
+		/* if the maximum of the 4 is the same as the
+		 * parent's value, we're done.
+		 */
+		if (tp->dmt_stree[pp] == max)
+			break;
+
+		/* parent gets new value.
+		 */
+		tp->dmt_stree[pp] = max;
+
+		/* parent becomes leaf for next go-round.
+		 */
+		lp = pp;
+	}
+}
+
+
+/*
+ * NAME:	dbFindLeaf()
+ *
+ * FUNCTION:	search a dmtree_t for sufficient free blocks, returning
+ *		the index of a leaf describing the free blocks if
+ *		sufficient free blocks are found.
+ *
+ *		the search starts at the top of the dmtree_t tree and
+ *		proceeds down the tree to the leftmost leaf with sufficient
+ *		free space.
+ *
+ * PARAMETERS:
+ *	tp	- pointer to the tree to be searched.
+ *	l2nb	- log2 number of free blocks to search for.
+ *	leafidx	- return pointer to be set to the index of the leaf
+ *		  describing at least l2nb free blocks if sufficient
+ *		  free blocks are found.
+ *	is_ctl	- determines if the tree is of type ctl
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOSPC	- insufficient free blocks.
+ */
+static int dbFindLeaf(dmtree_t *tp, int l2nb, int *leafidx, bool is_ctl)
+{
+	int ti, n = 0, k, x = 0;
+	int max_size;
+
+	max_size = is_ctl ? CTLTREESIZE : TREESIZE;
+
+	/* first check the root of the tree to see if there is
+	 * sufficient free space.
+	 */
+	if (l2nb > tp->dmt_stree[ROOT])
+		return -ENOSPC;
+
+	/* sufficient free space available. now search down the tree
+	 * starting at the next level for the leftmost leaf that
+	 * describes sufficient free space.
+	 */
+	for (k = le32_to_cpu(tp->dmt_height), ti = 1;
+	     k > 0; k--, ti = ((ti + n) << 2) + 1) {
+		/* search the four nodes at this level, starting from
+		 * the left.
+		 */
+		for (x = ti, n = 0; n < 4; n++) {
+			/* sufficient free space found.  move to the next
+			 * level (or quit if this is the last level).
+			 */
+			if (x + n > max_size)
+				return -ENOSPC;
+			if (l2nb <= tp->dmt_stree[x + n])
+				break;
+		}
+
+		/* better have found something since the higher
+		 * levels of the tree said it was here.
+		 */
+		assert(n < 4);
+	}
+
+	/* set the return to the leftmost leaf describing sufficient
+	 * free space.
+	 */
+	*leafidx = x + n - le32_to_cpu(tp->dmt_leafidx);
+
+	return (0);
+}
+
+
+/*
+ * NAME:	dbFindBits()
+ *
+ * FUNCTION:	find a specified number of binary buddy free bits within a
+ *		dmap bitmap word value.
+ *
+ *		this routine searches the bitmap value for (1 << l2nb) free
+ *		bits at (1 << l2nb) alignments within the value.
+ *
+ * PARAMETERS:
+ *	word	-  dmap bitmap word value.
+ *	l2nb	-  number of free bits specified as a log2 number.
+ *
+ * RETURN VALUES:
+ *	starting bit number of free bits.
+ */
+static int dbFindBits(u32 word, int l2nb)
+{
+	int bitno, nb;
+	u32 mask;
+
+	/* get the number of bits.
+	 */
+	nb = 1 << l2nb;
+	assert(nb <= DBWORD);
+
+	/* complement the word so we can use a mask (i.e. 0s represent
+	 * free bits) and compute the mask.
+	 */
+	word = ~word;
+	mask = ONES << (DBWORD - nb);
+
+	/* scan the word for nb free bits at nb alignments.
+	 */
+	for (bitno = 0; mask != 0; bitno += nb, mask >>= nb) {
+		if ((mask & word) == mask)
+			break;
+	}
+
+	ASSERT(bitno < 32);
+
+	/* return the bit number.
+	 */
+	return (bitno);
+}
+
+
+/*
+ * NAME:	dbMaxBud(u8 *cp)
+ *
+ * FUNCTION:	determine the largest binary buddy string of free
+ *		bits within 32-bits of the map.
+ *
+ * PARAMETERS:
+ *	cp	-  pointer to the 32-bit value.
+ *
+ * RETURN VALUES:
+ *	largest binary buddy of free bits within a dmap word.
+ */
+static int dbMaxBud(u8 * cp)
+{
+	signed char tmp1, tmp2;
+
+	/* check if the wmap word is all free. if so, the
+	 * free buddy size is BUDMIN.
+	 */
+	if (*((uint *) cp) == 0)
+		return (BUDMIN);
+
+	/* check if the wmap word is half free. if so, the
+	 * free buddy size is BUDMIN-1.
+	 */
+	if (*((u16 *) cp) == 0 || *((u16 *) cp + 1) == 0)
+		return (BUDMIN - 1);
+
+	/* not all free or half free. determine the free buddy
+	 * size thru table lookup using quarters of the wmap word.
+	 */
+	tmp1 = max(budtab[cp[2]], budtab[cp[3]]);
+	tmp2 = max(budtab[cp[0]], budtab[cp[1]]);
+	return (max(tmp1, tmp2));
+}
+
+
+/*
+ * NAME:	cnttz(uint word)
+ *
+ * FUNCTION:	determine the number of trailing zeros within a 32-bit
+ *		value.
+ *
+ * PARAMETERS:
+ *	value	-  32-bit value to be examined.
+ *
+ * RETURN VALUES:
+ *	count of trailing zeros
+ */
+static int cnttz(u32 word)
+{
+	int n;
+
+	for (n = 0; n < 32; n++, word >>= 1) {
+		if (word & 0x01)
+			break;
+	}
+
+	return (n);
+}
+
+
+/*
+ * NAME:	cntlz(u32 value)
+ *
+ * FUNCTION:	determine the number of leading zeros within a 32-bit
+ *		value.
+ *
+ * PARAMETERS:
+ *	value	-  32-bit value to be examined.
+ *
+ * RETURN VALUES:
+ *	count of leading zeros
+ */
+static int cntlz(u32 value)
+{
+	int n;
+
+	for (n = 0; n < 32; n++, value <<= 1) {
+		if (value & HIGHORDER)
+			break;
+	}
+	return (n);
+}
+
+
+/*
+ * NAME:	blkstol2(s64 nb)
+ *
+ * FUNCTION:	convert a block count to its log2 value. if the block
+ *		count is not a l2 multiple, it is rounded up to the next
+ *		larger l2 multiple.
+ *
+ * PARAMETERS:
+ *	nb	-  number of blocks
+ *
+ * RETURN VALUES:
+ *	log2 number of blocks
+ */
+static int blkstol2(s64 nb)
+{
+	int l2nb;
+	s64 mask;		/* meant to be signed */
+
+	mask = (s64) 1 << (64 - 1);
+
+	/* count the leading bits.
+	 */
+	for (l2nb = 0; l2nb < 64; l2nb++, mask >>= 1) {
+		/* leading bit found.
+		 */
+		if (nb & mask) {
+			/* determine the l2 value.
+			 */
+			l2nb = (64 - 1) - l2nb;
+
+			/* check if we need to round up.
+			 */
+			if (~mask & nb)
+				l2nb++;
+
+			return (l2nb);
+		}
+	}
+	assert(0);
+	return 0;		/* fix compiler warning */
+}
+
+
+/*
+ * NAME:	dbAllocBottomUp()
+ *
+ * FUNCTION:	alloc the specified block range from the working block
+ *		allocation map.
+ *
+ *		the blocks will be alloc from the working map one dmap
+ *		at a time.
+ *
+ * PARAMETERS:
+ *	ip	-  pointer to in-core inode;
+ *	blkno	-  starting block number to be freed.
+ *	nblocks	-  number of blocks to be freed.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error
+ */
+int dbAllocBottomUp(struct inode *ip, s64 blkno, s64 nblocks)
+{
+	struct metapage *mp;
+	struct dmap *dp;
+	int nb, rc;
+	s64 lblkno, rem;
+	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
+	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
+
+	IREAD_LOCK(ipbmap, RDWRLOCK_DMAP);
+
+	/* block to be allocated better be within the mapsize. */
+	ASSERT(nblocks <= bmp->db_mapsize - blkno);
+
+	/*
+	 * allocate the blocks a dmap at a time.
+	 */
+	mp = NULL;
+	for (rem = nblocks; rem > 0; rem -= nb, blkno += nb) {
+		/* release previous dmap if any */
+		if (mp) {
+			write_metapage(mp);
+		}
+
+		/* get the buffer for the current dmap. */
+		lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage);
+		mp = read_metapage(ipbmap, lblkno, PSIZE, 0);
+		if (mp == NULL) {
+			IREAD_UNLOCK(ipbmap);
+			return -EIO;
+		}
+		dp = (struct dmap *) mp->data;
+
+		/* determine the number of blocks to be allocated from
+		 * this dmap.
+		 */
+		nb = min(rem, BPERDMAP - (blkno & (BPERDMAP - 1)));
+
+		/* allocate the blocks. */
+		if ((rc = dbAllocDmapBU(bmp, dp, blkno, nb))) {
+			release_metapage(mp);
+			IREAD_UNLOCK(ipbmap);
+			return (rc);
+		}
+	}
+
+	/* write the last buffer. */
+	write_metapage(mp);
+
+	IREAD_UNLOCK(ipbmap);
+
+	return (0);
+}
+
+
+static int dbAllocDmapBU(struct bmap * bmp, struct dmap * dp, s64 blkno,
+			 int nblocks)
+{
+	int rc;
+	int dbitno, word, rembits, nb, nwords, wbitno, agno;
+	s8 oldroot;
+	struct dmaptree *tp = (struct dmaptree *) & dp->tree;
+
+	/* save the current value of the root (i.e. maximum free string)
+	 * of the dmap tree.
+	 */
+	oldroot = tp->stree[ROOT];
+
+	/* determine the bit number and word within the dmap of the
+	 * starting block.
+	 */
+	dbitno = blkno & (BPERDMAP - 1);
+	word = dbitno >> L2DBWORD;
+
+	/* block range better be within the dmap */
+	assert(dbitno + nblocks <= BPERDMAP);
+
+	/* allocate the bits of the dmap's words corresponding to the block
+	 * range. not all bits of the first and last words may be contained
+	 * within the block range.  if this is the case, we'll work against
+	 * those words (i.e. partial first and/or last) on an individual basis
+	 * (a single pass), allocating the bits of interest by hand and
+	 * updating the leaf corresponding to the dmap word. a single pass
+	 * will be used for all dmap words fully contained within the
+	 * specified range.  within this pass, the bits of all fully contained
+	 * dmap words will be marked as free in a single shot and the leaves
+	 * will be updated. a single leaf may describe the free space of
+	 * multiple dmap words, so we may update only a subset of the actual
+	 * leaves corresponding to the dmap words of the block range.
+	 */
+	for (rembits = nblocks; rembits > 0; rembits -= nb, dbitno += nb) {
+		/* determine the bit number within the word and
+		 * the number of bits within the word.
+		 */
+		wbitno = dbitno & (DBWORD - 1);
+		nb = min(rembits, DBWORD - wbitno);
+
+		/* check if only part of a word is to be allocated.
+		 */
+		if (nb < DBWORD) {
+			/* allocate (set to 1) the appropriate bits within
+			 * this dmap word.
+			 */
+			dp->wmap[word] |= cpu_to_le32(ONES << (DBWORD - nb)
+						      >> wbitno);
+
+			word++;
+		} else {
+			/* one or more dmap words are fully contained
+			 * within the block range.  determine how many
+			 * words and allocate (set to 1) the bits of these
+			 * words.
+			 */
+			nwords = rembits >> L2DBWORD;
+			memset(&dp->wmap[word], (int) ONES, nwords * 4);
+
+			/* determine how many bits */
+			nb = nwords << L2DBWORD;
+			word += nwords;
+		}
+	}
+
+	/* update the free count for this dmap */
+	le32_add_cpu(&dp->nfree, -nblocks);
+
+	/* reconstruct summary tree */
+	dbInitDmapTree(dp);
+
+	BMAP_LOCK(bmp);
+
+	/* if this allocation group is completely free,
+	 * update the highest active allocation group number
+	 * if this allocation group is the new max.
+	 */
+	agno = blkno >> bmp->db_agl2size;
+	if (agno > bmp->db_maxag)
+		bmp->db_maxag = agno;
+
+	/* update the free count for the allocation group and map */
+	bmp->db_agfree[agno] -= nblocks;
+	bmp->db_nfree -= nblocks;
+
+	BMAP_UNLOCK(bmp);
+
+	/* if the root has not changed, done. */
+	if (tp->stree[ROOT] == oldroot)
+		return (0);
+
+	/* root changed. bubble the change up to the dmap control pages.
+	 * if the adjustment of the upper level control pages fails,
+	 * backout the bit allocation (thus making everything consistent).
+	 */
+	if ((rc = dbAdjCtl(bmp, blkno, tp->stree[ROOT], 1, 0)))
+		dbFreeBits(bmp, dp, blkno, nblocks);
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	dbExtendFS()
+ *
+ * FUNCTION:	extend bmap from blkno for nblocks;
+ *		dbExtendFS() updates bmap ready for dbAllocBottomUp();
+ *
+ * L2
+ *  |
+ *   L1---------------------------------L1
+ *    |					 |
+ *     L0---------L0---------L0		  L0---------L0---------L0
+ *      |	   |	      |		   |	      |		 |
+ *	 d0,...,dn  d0,...,dn  d0,...,dn    d0,...,dn  d0,...,dn  d0,.,dm;
+ * L2L1L0d0,...,dnL0d0,...,dnL0d0,...,dnL1L0d0,...,dnL0d0,...,dnL0d0,..dm
+ *
+ * <---old---><----------------------------extend----------------------->
+ */
+int dbExtendFS(struct inode *ipbmap, s64 blkno,	s64 nblocks)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(ipbmap->i_sb);
+	int nbperpage = sbi->nbperpage;
+	int i, i0 = true, j, j0 = true, k, n;
+	s64 newsize;
+	s64 p;
+	struct metapage *mp, *l2mp, *l1mp = NULL, *l0mp = NULL;
+	struct dmapctl *l2dcp, *l1dcp, *l0dcp;
+	struct dmap *dp;
+	s8 *l0leaf, *l1leaf, *l2leaf;
+	struct bmap *bmp = sbi->bmap;
+	int agno, l2agsize, oldl2agsize;
+	s64 ag_rem;
+
+	newsize = blkno + nblocks;
+
+	jfs_info("dbExtendFS: blkno:%Ld nblocks:%Ld newsize:%Ld",
+		 (long long) blkno, (long long) nblocks, (long long) newsize);
+
+	/*
+	 *	initialize bmap control page.
+	 *
+	 * all the data in bmap control page should exclude
+	 * the mkfs hidden dmap page.
+	 */
+
+	/* update mapsize */
+	bmp->db_mapsize = newsize;
+	bmp->db_maxlevel = BMAPSZTOLEV(bmp->db_mapsize);
+
+	/* compute new AG size */
+	l2agsize = dbGetL2AGSize(newsize);
+	oldl2agsize = bmp->db_agl2size;
+
+	bmp->db_agl2size = l2agsize;
+	bmp->db_agsize = 1 << l2agsize;
+
+	/* compute new number of AG */
+	agno = bmp->db_numag;
+	bmp->db_numag = newsize >> l2agsize;
+	bmp->db_numag += ((u32) newsize % (u32) bmp->db_agsize) ? 1 : 0;
+
+	/*
+	 *	reconfigure db_agfree[]
+	 * from old AG configuration to new AG configuration;
+	 *
+	 * coalesce contiguous k (newAGSize/oldAGSize) AGs;
+	 * i.e., (AGi, ..., AGj) where i = k*n and j = k*(n+1) - 1 to AGn;
+	 * note: new AG size = old AG size * (2**x).
+	 */
+	if (l2agsize == oldl2agsize)
+		goto extend;
+	k = 1 << (l2agsize - oldl2agsize);
+	ag_rem = bmp->db_agfree[0];	/* save agfree[0] */
+	for (i = 0, n = 0; i < agno; n++) {
+		bmp->db_agfree[n] = 0;	/* init collection point */
+
+		/* coalesce contiguous k AGs; */
+		for (j = 0; j < k && i < agno; j++, i++) {
+			/* merge AGi to AGn */
+			bmp->db_agfree[n] += bmp->db_agfree[i];
+		}
+	}
+	bmp->db_agfree[0] += ag_rem;	/* restore agfree[0] */
+
+	for (; n < MAXAG; n++)
+		bmp->db_agfree[n] = 0;
+
+	/*
+	 * update highest active ag number
+	 */
+
+	bmp->db_maxag = bmp->db_maxag / k;
+
+	/*
+	 *	extend bmap
+	 *
+	 * update bit maps and corresponding level control pages;
+	 * global control page db_nfree, db_agfree[agno], db_maxfreebud;
+	 */
+      extend:
+	/* get L2 page */
+	p = BMAPBLKNO + nbperpage;	/* L2 page */
+	l2mp = read_metapage(ipbmap, p, PSIZE, 0);
+	if (!l2mp) {
+		jfs_error(ipbmap->i_sb, "L2 page could not be read\n");
+		return -EIO;
+	}
+	l2dcp = (struct dmapctl *) l2mp->data;
+
+	/* compute start L1 */
+	k = blkno >> L2MAXL1SIZE;
+	l2leaf = l2dcp->stree + CTLLEAFIND + k;
+	p = BLKTOL1(blkno, sbi->l2nbperpage);	/* L1 page */
+
+	/*
+	 * extend each L1 in L2
+	 */
+	for (; k < LPERCTL; k++, p += nbperpage) {
+		/* get L1 page */
+		if (j0) {
+			/* read in L1 page: (blkno & (MAXL1SIZE - 1)) */
+			l1mp = read_metapage(ipbmap, p, PSIZE, 0);
+			if (l1mp == NULL)
+				goto errout;
+			l1dcp = (struct dmapctl *) l1mp->data;
+
+			/* compute start L0 */
+			j = (blkno & (MAXL1SIZE - 1)) >> L2MAXL0SIZE;
+			l1leaf = l1dcp->stree + CTLLEAFIND + j;
+			p = BLKTOL0(blkno, sbi->l2nbperpage);
+			j0 = false;
+		} else {
+			/* assign/init L1 page */
+			l1mp = get_metapage(ipbmap, p, PSIZE, 0);
+			if (l1mp == NULL)
+				goto errout;
+
+			l1dcp = (struct dmapctl *) l1mp->data;
+
+			/* compute start L0 */
+			j = 0;
+			l1leaf = l1dcp->stree + CTLLEAFIND;
+			p += nbperpage;	/* 1st L0 of L1.k */
+		}
+
+		/*
+		 * extend each L0 in L1
+		 */
+		for (; j < LPERCTL; j++) {
+			/* get L0 page */
+			if (i0) {
+				/* read in L0 page: (blkno & (MAXL0SIZE - 1)) */
+
+				l0mp = read_metapage(ipbmap, p, PSIZE, 0);
+				if (l0mp == NULL)
+					goto errout;
+				l0dcp = (struct dmapctl *) l0mp->data;
+
+				/* compute start dmap */
+				i = (blkno & (MAXL0SIZE - 1)) >>
+				    L2BPERDMAP;
+				l0leaf = l0dcp->stree + CTLLEAFIND + i;
+				p = BLKTODMAP(blkno,
+					      sbi->l2nbperpage);
+				i0 = false;
+			} else {
+				/* assign/init L0 page */
+				l0mp = get_metapage(ipbmap, p, PSIZE, 0);
+				if (l0mp == NULL)
+					goto errout;
+
+				l0dcp = (struct dmapctl *) l0mp->data;
+
+				/* compute start dmap */
+				i = 0;
+				l0leaf = l0dcp->stree + CTLLEAFIND;
+				p += nbperpage;	/* 1st dmap of L0.j */
+			}
+
+			/*
+			 * extend each dmap in L0
+			 */
+			for (; i < LPERCTL; i++) {
+				/*
+				 * reconstruct the dmap page, and
+				 * initialize corresponding parent L0 leaf
+				 */
+				if ((n = blkno & (BPERDMAP - 1))) {
+					/* read in dmap page: */
+					mp = read_metapage(ipbmap, p,
+							   PSIZE, 0);
+					if (mp == NULL)
+						goto errout;
+					n = min(nblocks, (s64)BPERDMAP - n);
+				} else {
+					/* assign/init dmap page */
+					mp = read_metapage(ipbmap, p,
+							   PSIZE, 0);
+					if (mp == NULL)
+						goto errout;
+
+					n = min_t(s64, nblocks, BPERDMAP);
+				}
+
+				dp = (struct dmap *) mp->data;
+				*l0leaf = dbInitDmap(dp, blkno, n);
+
+				bmp->db_nfree += n;
+				agno = le64_to_cpu(dp->start) >> l2agsize;
+				bmp->db_agfree[agno] += n;
+
+				write_metapage(mp);
+
+				l0leaf++;
+				p += nbperpage;
+
+				blkno += n;
+				nblocks -= n;
+				if (nblocks == 0)
+					break;
+			}	/* for each dmap in a L0 */
+
+			/*
+			 * build current L0 page from its leaves, and
+			 * initialize corresponding parent L1 leaf
+			 */
+			*l1leaf = dbInitDmapCtl(l0dcp, 0, ++i);
+			write_metapage(l0mp);
+			l0mp = NULL;
+
+			if (nblocks)
+				l1leaf++;	/* continue for next L0 */
+			else {
+				/* more than 1 L0 ? */
+				if (j > 0)
+					break;	/* build L1 page */
+				else {
+					/* summarize in global bmap page */
+					bmp->db_maxfreebud = *l1leaf;
+					release_metapage(l1mp);
+					release_metapage(l2mp);
+					goto finalize;
+				}
+			}
+		}		/* for each L0 in a L1 */
+
+		/*
+		 * build current L1 page from its leaves, and
+		 * initialize corresponding parent L2 leaf
+		 */
+		*l2leaf = dbInitDmapCtl(l1dcp, 1, ++j);
+		write_metapage(l1mp);
+		l1mp = NULL;
+
+		if (nblocks)
+			l2leaf++;	/* continue for next L1 */
+		else {
+			/* more than 1 L1 ? */
+			if (k > 0)
+				break;	/* build L2 page */
+			else {
+				/* summarize in global bmap page */
+				bmp->db_maxfreebud = *l2leaf;
+				release_metapage(l2mp);
+				goto finalize;
+			}
+		}
+	}			/* for each L1 in a L2 */
+
+	jfs_error(ipbmap->i_sb, "function has not returned as expected\n");
+errout:
+	if (l0mp)
+		release_metapage(l0mp);
+	if (l1mp)
+		release_metapage(l1mp);
+	release_metapage(l2mp);
+	return -EIO;
+
+	/*
+	 *	finalize bmap control page
+	 */
+finalize:
+
+	return 0;
+}
+
+
+/*
+ *	dbFinalizeBmap()
+ */
+void dbFinalizeBmap(struct inode *ipbmap)
+{
+	struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap;
+	int actags, inactags, l2nl;
+	s64 ag_rem, actfree, inactfree, avgfree;
+	int i, n;
+
+	/*
+	 *	finalize bmap control page
+	 */
+//finalize:
+	/*
+	 * compute db_agpref: preferred ag to allocate from
+	 * (the leftmost ag with average free space in it);
+	 */
+//agpref:
+	/* get the number of active ags and inactive ags */
+	actags = bmp->db_maxag + 1;
+	inactags = bmp->db_numag - actags;
+	ag_rem = bmp->db_mapsize & (bmp->db_agsize - 1);	/* ??? */
+
+	/* determine how many blocks are in the inactive allocation
+	 * groups. in doing this, we must account for the fact that
+	 * the rightmost group might be a partial group (i.e. file
+	 * system size is not a multiple of the group size).
+	 */
+	inactfree = (inactags && ag_rem) ?
+	    ((inactags - 1) << bmp->db_agl2size) + ag_rem
+	    : inactags << bmp->db_agl2size;
+
+	/* determine how many free blocks are in the active
+	 * allocation groups plus the average number of free blocks
+	 * within the active ags.
+	 */
+	actfree = bmp->db_nfree - inactfree;
+	avgfree = (u32) actfree / (u32) actags;
+
+	/* if the preferred allocation group has not average free space.
+	 * re-establish the preferred group as the leftmost
+	 * group with average free space.
+	 */
+	if (bmp->db_agfree[bmp->db_agpref] < avgfree) {
+		for (bmp->db_agpref = 0; bmp->db_agpref < actags;
+		     bmp->db_agpref++) {
+			if (bmp->db_agfree[bmp->db_agpref] >= avgfree)
+				break;
+		}
+		if (bmp->db_agpref >= bmp->db_numag) {
+			jfs_error(ipbmap->i_sb,
+				  "cannot find ag with average freespace\n");
+		}
+	}
+
+	/*
+	 * compute db_aglevel, db_agheight, db_width, db_agstart:
+	 * an ag is covered in aglevel dmapctl summary tree,
+	 * at agheight level height (from leaf) with agwidth number of nodes
+	 * each, which starts at agstart index node of the smmary tree node
+	 * array;
+	 */
+	bmp->db_aglevel = BMAPSZTOLEV(bmp->db_agsize);
+	l2nl =
+	    bmp->db_agl2size - (L2BPERDMAP + bmp->db_aglevel * L2LPERCTL);
+	bmp->db_agheight = l2nl >> 1;
+	bmp->db_agwidth = 1 << (l2nl - (bmp->db_agheight << 1));
+	for (i = 5 - bmp->db_agheight, bmp->db_agstart = 0, n = 1; i > 0;
+	     i--) {
+		bmp->db_agstart += n;
+		n <<= 2;
+	}
+
+}
+
+
+/*
+ * NAME:	dbInitDmap()/ujfs_idmap_page()
+ *
+ * FUNCTION:	initialize working/persistent bitmap of the dmap page
+ *		for the specified number of blocks:
+ *
+ *		at entry, the bitmaps had been initialized as free (ZEROS);
+ *		The number of blocks will only account for the actually
+ *		existing blocks. Blocks which don't actually exist in
+ *		the aggregate will be marked as allocated (ONES);
+ *
+ * PARAMETERS:
+ *	dp	- pointer to page of map
+ *	nblocks	- number of blocks this page
+ *
+ * RETURNS: NONE
+ */
+static int dbInitDmap(struct dmap * dp, s64 Blkno, int nblocks)
+{
+	int blkno, w, b, r, nw, nb, i;
+
+	/* starting block number within the dmap */
+	blkno = Blkno & (BPERDMAP - 1);
+
+	if (blkno == 0) {
+		dp->nblocks = dp->nfree = cpu_to_le32(nblocks);
+		dp->start = cpu_to_le64(Blkno);
+
+		if (nblocks == BPERDMAP) {
+			memset(&dp->wmap[0], 0, LPERDMAP * 4);
+			memset(&dp->pmap[0], 0, LPERDMAP * 4);
+			goto initTree;
+		}
+	} else {
+		le32_add_cpu(&dp->nblocks, nblocks);
+		le32_add_cpu(&dp->nfree, nblocks);
+	}
+
+	/* word number containing start block number */
+	w = blkno >> L2DBWORD;
+
+	/*
+	 * free the bits corresponding to the block range (ZEROS):
+	 * note: not all bits of the first and last words may be contained
+	 * within the block range.
+	 */
+	for (r = nblocks; r > 0; r -= nb, blkno += nb) {
+		/* number of bits preceding range to be freed in the word */
+		b = blkno & (DBWORD - 1);
+		/* number of bits to free in the word */
+		nb = min(r, DBWORD - b);
+
+		/* is partial word to be freed ? */
+		if (nb < DBWORD) {
+			/* free (set to 0) from the bitmap word */
+			dp->wmap[w] &= cpu_to_le32(~(ONES << (DBWORD - nb)
+						     >> b));
+			dp->pmap[w] &= cpu_to_le32(~(ONES << (DBWORD - nb)
+						     >> b));
+
+			/* skip the word freed */
+			w++;
+		} else {
+			/* free (set to 0) contiguous bitmap words */
+			nw = r >> L2DBWORD;
+			memset(&dp->wmap[w], 0, nw * 4);
+			memset(&dp->pmap[w], 0, nw * 4);
+
+			/* skip the words freed */
+			nb = nw << L2DBWORD;
+			w += nw;
+		}
+	}
+
+	/*
+	 * mark bits following the range to be freed (non-existing
+	 * blocks) as allocated (ONES)
+	 */
+
+	if (blkno == BPERDMAP)
+		goto initTree;
+
+	/* the first word beyond the end of existing blocks */
+	w = blkno >> L2DBWORD;
+
+	/* does nblocks fall on a 32-bit boundary ? */
+	b = blkno & (DBWORD - 1);
+	if (b) {
+		/* mark a partial word allocated */
+		dp->wmap[w] = dp->pmap[w] = cpu_to_le32(ONES >> b);
+		w++;
+	}
+
+	/* set the rest of the words in the page to allocated (ONES) */
+	for (i = w; i < LPERDMAP; i++)
+		dp->pmap[i] = dp->wmap[i] = cpu_to_le32(ONES);
+
+	/*
+	 * init tree
+	 */
+      initTree:
+	return (dbInitDmapTree(dp));
+}
+
+
+/*
+ * NAME:	dbInitDmapTree()/ujfs_complete_dmap()
+ *
+ * FUNCTION:	initialize summary tree of the specified dmap:
+ *
+ *		at entry, bitmap of the dmap has been initialized;
+ *
+ * PARAMETERS:
+ *	dp	- dmap to complete
+ *	blkno	- starting block number for this dmap
+ *	treemax	- will be filled in with max free for this dmap
+ *
+ * RETURNS:	max free string at the root of the tree
+ */
+static int dbInitDmapTree(struct dmap * dp)
+{
+	struct dmaptree *tp;
+	s8 *cp;
+	int i;
+
+	/* init fixed info of tree */
+	tp = &dp->tree;
+	tp->nleafs = cpu_to_le32(LPERDMAP);
+	tp->l2nleafs = cpu_to_le32(L2LPERDMAP);
+	tp->leafidx = cpu_to_le32(LEAFIND);
+	tp->height = cpu_to_le32(4);
+	tp->budmin = BUDMIN;
+
+	/* init each leaf from corresponding wmap word:
+	 * note: leaf is set to NOFREE(-1) if all blocks of corresponding
+	 * bitmap word are allocated.
+	 */
+	cp = tp->stree + le32_to_cpu(tp->leafidx);
+	for (i = 0; i < LPERDMAP; i++)
+		*cp++ = dbMaxBud((u8 *) & dp->wmap[i]);
+
+	/* build the dmap's binary buddy summary tree */
+	return (dbInitTree(tp));
+}
+
+
+/*
+ * NAME:	dbInitTree()/ujfs_adjtree()
+ *
+ * FUNCTION:	initialize binary buddy summary tree of a dmap or dmapctl.
+ *
+ *		at entry, the leaves of the tree has been initialized
+ *		from corresponding bitmap word or root of summary tree
+ *		of the child control page;
+ *		configure binary buddy system at the leaf level, then
+ *		bubble up the values of the leaf nodes up the tree.
+ *
+ * PARAMETERS:
+ *	cp	- Pointer to the root of the tree
+ *	l2leaves- Number of leaf nodes as a power of 2
+ *	l2min	- Number of blocks that can be covered by a leaf
+ *		  as a power of 2
+ *
+ * RETURNS: max free string at the root of the tree
+ */
+static int dbInitTree(struct dmaptree * dtp)
+{
+	int l2max, l2free, bsize, nextb, i;
+	int child, parent, nparent;
+	s8 *tp, *cp, *cp1;
+
+	tp = dtp->stree;
+
+	/* Determine the maximum free string possible for the leaves */
+	l2max = le32_to_cpu(dtp->l2nleafs) + dtp->budmin;
+
+	/*
+	 * configure the leaf levevl into binary buddy system
+	 *
+	 * Try to combine buddies starting with a buddy size of 1
+	 * (i.e. two leaves). At a buddy size of 1 two buddy leaves
+	 * can be combined if both buddies have a maximum free of l2min;
+	 * the combination will result in the left-most buddy leaf having
+	 * a maximum free of l2min+1.
+	 * After processing all buddies for a given size, process buddies
+	 * at the next higher buddy size (i.e. current size * 2) and
+	 * the next maximum free (current free + 1).
+	 * This continues until the maximum possible buddy combination
+	 * yields maximum free.
+	 */
+	for (l2free = dtp->budmin, bsize = 1; l2free < l2max;
+	     l2free++, bsize = nextb) {
+		/* get next buddy size == current buddy pair size */
+		nextb = bsize << 1;
+
+		/* scan each adjacent buddy pair at current buddy size */
+		for (i = 0, cp = tp + le32_to_cpu(dtp->leafidx);
+		     i < le32_to_cpu(dtp->nleafs);
+		     i += nextb, cp += nextb) {
+			/* coalesce if both adjacent buddies are max free */
+			if (*cp == l2free && *(cp + bsize) == l2free) {
+				*cp = l2free + 1;	/* left take right */
+				*(cp + bsize) = -1;	/* right give left */
+			}
+		}
+	}
+
+	/*
+	 * bubble summary information of leaves up the tree.
+	 *
+	 * Starting at the leaf node level, the four nodes described by
+	 * the higher level parent node are compared for a maximum free and
+	 * this maximum becomes the value of the parent node.
+	 * when all lower level nodes are processed in this fashion then
+	 * move up to the next level (parent becomes a lower level node) and
+	 * continue the process for that level.
+	 */
+	for (child = le32_to_cpu(dtp->leafidx),
+	     nparent = le32_to_cpu(dtp->nleafs) >> 2;
+	     nparent > 0; nparent >>= 2, child = parent) {
+		/* get index of 1st node of parent level */
+		parent = (child - 1) >> 2;
+
+		/* set the value of the parent node as the maximum
+		 * of the four nodes of the current level.
+		 */
+		for (i = 0, cp = tp + child, cp1 = tp + parent;
+		     i < nparent; i++, cp += 4, cp1++)
+			*cp1 = TREEMAX(cp);
+	}
+
+	return (*tp);
+}
+
+
+/*
+ *	dbInitDmapCtl()
+ *
+ * function: initialize dmapctl page
+ */
+static int dbInitDmapCtl(struct dmapctl * dcp, int level, int i)
+{				/* start leaf index not covered by range */
+	s8 *cp;
+
+	dcp->nleafs = cpu_to_le32(LPERCTL);
+	dcp->l2nleafs = cpu_to_le32(L2LPERCTL);
+	dcp->leafidx = cpu_to_le32(CTLLEAFIND);
+	dcp->height = cpu_to_le32(5);
+	dcp->budmin = L2BPERDMAP + L2LPERCTL * level;
+
+	/*
+	 * initialize the leaves of current level that were not covered
+	 * by the specified input block range (i.e. the leaves have no
+	 * low level dmapctl or dmap).
+	 */
+	cp = &dcp->stree[CTLLEAFIND + i];
+	for (; i < LPERCTL; i++)
+		*cp++ = NOFREE;
+
+	/* build the dmap's binary buddy summary tree */
+	return (dbInitTree((struct dmaptree *) dcp));
+}
+
+
+/*
+ * NAME:	dbGetL2AGSize()/ujfs_getagl2size()
+ *
+ * FUNCTION:	Determine log2(allocation group size) from aggregate size
+ *
+ * PARAMETERS:
+ *	nblocks	- Number of blocks in aggregate
+ *
+ * RETURNS: log2(allocation group size) in aggregate blocks
+ */
+static int dbGetL2AGSize(s64 nblocks)
+{
+	s64 sz;
+	s64 m;
+	int l2sz;
+
+	if (nblocks < BPERDMAP * MAXAG)
+		return (L2BPERDMAP);
+
+	/* round up aggregate size to power of 2 */
+	m = ((u64) 1 << (64 - 1));
+	for (l2sz = 64; l2sz >= 0; l2sz--, m >>= 1) {
+		if (m & nblocks)
+			break;
+	}
+
+	sz = (s64) 1 << l2sz;
+	if (sz < nblocks)
+		l2sz += 1;
+
+	/* agsize = roundupSize/max_number_of_ag */
+	return (l2sz - L2MAXAG);
+}
+
+
+/*
+ * NAME:	dbMapFileSizeToMapSize()
+ *
+ * FUNCTION:	compute number of blocks the block allocation map file
+ *		can cover from the map file size;
+ *
+ * RETURNS:	Number of blocks which can be covered by this block map file;
+ */
+
+/*
+ * maximum number of map pages at each level including control pages
+ */
+#define MAXL0PAGES	(1 + LPERCTL)
+#define MAXL1PAGES	(1 + LPERCTL * MAXL0PAGES)
+
+/*
+ * convert number of map pages to the zero origin top dmapctl level
+ */
+#define BMAPPGTOLEV(npages)	\
+	(((npages) <= 3 + MAXL0PAGES) ? 0 : \
+	 ((npages) <= 2 + MAXL1PAGES) ? 1 : 2)
+
+s64 dbMapFileSizeToMapSize(struct inode * ipbmap)
+{
+	struct super_block *sb = ipbmap->i_sb;
+	s64 nblocks;
+	s64 npages, ndmaps;
+	int level, i;
+	int complete, factor;
+
+	nblocks = ipbmap->i_size >> JFS_SBI(sb)->l2bsize;
+	npages = nblocks >> JFS_SBI(sb)->l2nbperpage;
+	level = BMAPPGTOLEV(npages);
+
+	/* At each level, accumulate the number of dmap pages covered by
+	 * the number of full child levels below it;
+	 * repeat for the last incomplete child level.
+	 */
+	ndmaps = 0;
+	npages--;		/* skip the first global control page */
+	/* skip higher level control pages above top level covered by map */
+	npages -= (2 - level);
+	npages--;		/* skip top level's control page */
+	for (i = level; i >= 0; i--) {
+		factor =
+		    (i == 2) ? MAXL1PAGES : ((i == 1) ? MAXL0PAGES : 1);
+		complete = (u32) npages / factor;
+		ndmaps += complete * ((i == 2) ? LPERCTL * LPERCTL :
+				      ((i == 1) ? LPERCTL : 1));
+
+		/* pages in last/incomplete child */
+		npages = (u32) npages % factor;
+		/* skip incomplete child's level control page */
+		npages--;
+	}
+
+	/* convert the number of dmaps into the number of blocks
+	 * which can be covered by the dmaps;
+	 */
+	nblocks = ndmaps << L2BPERDMAP;
+
+	return (nblocks);
+}
diff --git a/fs/jfs/jfs_dmap.h b/fs/jfs/jfs_dmap.h
new file mode 100644
index 000000000..aa03a904d
--- /dev/null
+++ b/fs/jfs/jfs_dmap.h
@@ -0,0 +1,303 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ */
+#ifndef	_H_JFS_DMAP
+#define _H_JFS_DMAP
+
+#include "jfs_txnmgr.h"
+
+#define BMAPVERSION	1	/* version number */
+#define	TREESIZE	(256+64+16+4+1)	/* size of a dmap tree */
+#define	LEAFIND		(64+16+4+1)	/* index of 1st leaf of a dmap tree */
+#define LPERDMAP	256	/* num leaves per dmap tree */
+#define L2LPERDMAP	8	/* l2 number of leaves per dmap tree */
+#define	DBWORD		32	/* # of blks covered by a map word */
+#define	L2DBWORD	5	/* l2 # of blks covered by a mword */
+#define BUDMIN		L2DBWORD	/* max free string in a map word */
+#define BPERDMAP	(LPERDMAP * DBWORD)	/* num of blks per dmap */
+#define L2BPERDMAP	13	/* l2 num of blks per dmap */
+#define CTLTREESIZE	(1024+256+64+16+4+1)	/* size of a dmapctl tree */
+#define CTLLEAFIND	(256+64+16+4+1)	/* idx of 1st leaf of a dmapctl tree */
+#define LPERCTL		1024	/* num of leaves per dmapctl tree */
+#define L2LPERCTL	10	/* l2 num of leaves per dmapctl tree */
+#define	ROOT		0	/* index of the root of a tree */
+#define	NOFREE		((s8) -1)	/* no blocks free */
+#define	MAXAG		128	/* max number of allocation groups */
+#define L2MAXAG		7	/* l2 max num of AG */
+#define L2MINAGSZ	25	/* l2 of minimum AG size in bytes */
+#define	BMAPBLKNO	0	/* lblkno of bmap within the map */
+
+/*
+ * maximum l2 number of disk blocks at the various dmapctl levels.
+ */
+#define	L2MAXL0SIZE	(L2BPERDMAP + 1 * L2LPERCTL)
+#define	L2MAXL1SIZE	(L2BPERDMAP + 2 * L2LPERCTL)
+#define	L2MAXL2SIZE	(L2BPERDMAP + 3 * L2LPERCTL)
+
+/*
+ * maximum number of disk blocks at the various dmapctl levels.
+ */
+#define	MAXL0SIZE	((s64)1 << L2MAXL0SIZE)
+#define	MAXL1SIZE	((s64)1 << L2MAXL1SIZE)
+#define	MAXL2SIZE	((s64)1 << L2MAXL2SIZE)
+
+#define	MAXMAPSIZE	MAXL2SIZE	/* maximum aggregate map size */
+
+/*
+ * determine the maximum free string for four (lower level) nodes
+ * of the tree.
+ */
+static inline signed char TREEMAX(signed char *cp)
+{
+	signed char tmp1, tmp2;
+
+	tmp1 = max(*(cp+2), *(cp+3));
+	tmp2 = max(*(cp), *(cp+1));
+
+	return max(tmp1, tmp2);
+}
+
+/*
+ * convert disk block number to the logical block number of the dmap
+ * describing the disk block.  s is the log2(number of logical blocks per page)
+ *
+ * The calculation figures out how many logical pages are in front of the dmap.
+ *	- the number of dmaps preceding it
+ *	- the number of L0 pages preceding its L0 page
+ *	- the number of L1 pages preceding its L1 page
+ *	- 3 is added to account for the L2, L1, and L0 page for this dmap
+ *	- 1 is added to account for the control page of the map.
+ */
+#define BLKTODMAP(b,s)    \
+	((((b) >> 13) + ((b) >> 23) + ((b) >> 33) + 3 + 1) << (s))
+
+/*
+ * convert disk block number to the logical block number of the LEVEL 0
+ * dmapctl describing the disk block.  s is the log2(number of logical blocks
+ * per page)
+ *
+ * The calculation figures out how many logical pages are in front of the L0.
+ *	- the number of dmap pages preceding it
+ *	- the number of L0 pages preceding it
+ *	- the number of L1 pages preceding its L1 page
+ *	- 2 is added to account for the L2, and L1 page for this L0
+ *	- 1 is added to account for the control page of the map.
+ */
+#define BLKTOL0(b,s)      \
+	(((((b) >> 23) << 10) + ((b) >> 23) + ((b) >> 33) + 2 + 1) << (s))
+
+/*
+ * convert disk block number to the logical block number of the LEVEL 1
+ * dmapctl describing the disk block.  s is the log2(number of logical blocks
+ * per page)
+ *
+ * The calculation figures out how many logical pages are in front of the L1.
+ *	- the number of dmap pages preceding it
+ *	- the number of L0 pages preceding it
+ *	- the number of L1 pages preceding it
+ *	- 1 is added to account for the L2 page
+ *	- 1 is added to account for the control page of the map.
+ */
+#define BLKTOL1(b,s)      \
+     (((((b) >> 33) << 20) + (((b) >> 33) << 10) + ((b) >> 33) + 1 + 1) << (s))
+
+/*
+ * convert disk block number to the logical block number of the dmapctl
+ * at the specified level which describes the disk block.
+ */
+#define BLKTOCTL(b,s,l)   \
+	(((l) == 2) ? 1 : ((l) == 1) ? BLKTOL1((b),(s)) : BLKTOL0((b),(s)))
+
+/*
+ * convert aggregate map size to the zero origin dmapctl level of the
+ * top dmapctl.
+ */
+#define	BMAPSZTOLEV(size)	\
+	(((size) <= MAXL0SIZE) ? 0 : ((size) <= MAXL1SIZE) ? 1 : 2)
+
+/* convert disk block number to allocation group number.
+ */
+#define BLKTOAG(b,sbi)	((b) >> ((sbi)->bmap->db_agl2size))
+
+/* convert allocation group number to starting disk block
+ * number.
+ */
+#define AGTOBLK(a,ip)	\
+	((s64)(a) << (JFS_SBI((ip)->i_sb)->bmap->db_agl2size))
+
+/*
+ *	dmap summary tree
+ *
+ * dmaptree must be consistent with dmapctl.
+ */
+struct dmaptree {
+	__le32 nleafs;		/* 4: number of tree leafs	*/
+	__le32 l2nleafs;	/* 4: l2 number of tree leafs	*/
+	__le32 leafidx;		/* 4: index of first tree leaf	*/
+	__le32 height;		/* 4: height of the tree	*/
+	s8 budmin;		/* 1: min l2 tree leaf value to combine */
+	s8 stree[TREESIZE];	/* TREESIZE: tree		*/
+	u8 pad[2];		/* 2: pad to word boundary	*/
+};				/* - 360 -			*/
+
+/*
+ *	dmap page per 8K blocks bitmap
+ */
+struct dmap {
+	__le32 nblocks;		/* 4: num blks covered by this dmap	*/
+	__le32 nfree;		/* 4: num of free blks in this dmap	*/
+	__le64 start;		/* 8: starting blkno for this dmap	*/
+	struct dmaptree tree;	/* 360: dmap tree			*/
+	u8 pad[1672];		/* 1672: pad to 2048 bytes		*/
+	__le32 wmap[LPERDMAP];	/* 1024: bits of the working map	*/
+	__le32 pmap[LPERDMAP];	/* 1024: bits of the persistent map	*/
+};				/* - 4096 -				*/
+
+/*
+ *	disk map control page per level.
+ *
+ * dmapctl must be consistent with dmaptree.
+ */
+struct dmapctl {
+	__le32 nleafs;		/* 4: number of tree leafs	*/
+	__le32 l2nleafs;	/* 4: l2 number of tree leafs	*/
+	__le32 leafidx;		/* 4: index of the first tree leaf	*/
+	__le32 height;		/* 4: height of tree		*/
+	s8 budmin;		/* 1: minimum l2 tree leaf value	*/
+	s8 stree[CTLTREESIZE];	/* CTLTREESIZE: dmapctl tree	*/
+	u8 pad[2714];		/* 2714: pad to 4096		*/
+};				/* - 4096 -			*/
+
+/*
+ *	common definition for dmaptree within dmap and dmapctl
+ */
+typedef union dmtree {
+	struct dmaptree t1;
+	struct dmapctl t2;
+} dmtree_t;
+
+/* macros for accessing fields within dmtree */
+#define	dmt_nleafs	t1.nleafs
+#define	dmt_l2nleafs	t1.l2nleafs
+#define	dmt_leafidx	t1.leafidx
+#define	dmt_height	t1.height
+#define	dmt_budmin	t1.budmin
+#define	dmt_stree	t2.stree
+
+/*
+ *	on-disk aggregate disk allocation map descriptor.
+ */
+struct dbmap_disk {
+	__le64 dn_mapsize;	/* 8: number of blocks in aggregate	*/
+	__le64 dn_nfree;	/* 8: num free blks in aggregate map	*/
+	__le32 dn_l2nbperpage;	/* 4: number of blks per page		*/
+	__le32 dn_numag;	/* 4: total number of ags		*/
+	__le32 dn_maxlevel;	/* 4: number of active ags		*/
+	__le32 dn_maxag;	/* 4: max active alloc group number	*/
+	__le32 dn_agpref;	/* 4: preferred alloc group (hint)	*/
+	__le32 dn_aglevel;	/* 4: dmapctl level holding the AG	*/
+	__le32 dn_agheight;	/* 4: height in dmapctl of the AG	*/
+	__le32 dn_agwidth;	/* 4: width in dmapctl of the AG	*/
+	__le32 dn_agstart;	/* 4: start tree index at AG height	*/
+	__le32 dn_agl2size;	/* 4: l2 num of blks per alloc group	*/
+	__le64 dn_agfree[MAXAG];/* 8*MAXAG: per AG free count		*/
+	__le64 dn_agsize;	/* 8: num of blks per alloc group	*/
+	s8 dn_maxfreebud;	/* 1: max free buddy system		*/
+	u8 pad[3007];		/* 3007: pad to 4096			*/
+};				/* - 4096 -				*/
+
+struct dbmap {
+	s64 dn_mapsize;		/* number of blocks in aggregate	*/
+	s64 dn_nfree;		/* num free blks in aggregate map	*/
+	int dn_l2nbperpage;	/* number of blks per page		*/
+	int dn_numag;		/* total number of ags			*/
+	int dn_maxlevel;	/* number of active ags			*/
+	int dn_maxag;		/* max active alloc group number	*/
+	int dn_agpref;		/* preferred alloc group (hint)		*/
+	int dn_aglevel;		/* dmapctl level holding the AG		*/
+	int dn_agheight;	/* height in dmapctl of the AG		*/
+	int dn_agwidth;		/* width in dmapctl of the AG		*/
+	int dn_agstart;		/* start tree index at AG height	*/
+	int dn_agl2size;	/* l2 num of blks per alloc group	*/
+	s64 dn_agfree[MAXAG];	/* per AG free count			*/
+	s64 dn_agsize;		/* num of blks per alloc group		*/
+	signed char dn_maxfreebud;	/* max free buddy system	*/
+};				/* - 4096 -				*/
+/*
+ *	in-memory aggregate disk allocation map descriptor.
+ */
+struct bmap {
+	struct dbmap db_bmap;		/* on-disk aggregate map descriptor */
+	struct inode *db_ipbmap;	/* ptr to aggregate map incore inode */
+	struct mutex db_bmaplock;	/* aggregate map lock */
+	atomic_t db_active[MAXAG];	/* count of active, open files in AG */
+	u32 *db_DBmap;
+};
+
+/* macros for accessing fields within in-memory aggregate map descriptor */
+#define	db_mapsize	db_bmap.dn_mapsize
+#define	db_nfree	db_bmap.dn_nfree
+#define	db_agfree	db_bmap.dn_agfree
+#define	db_agsize	db_bmap.dn_agsize
+#define	db_agl2size	db_bmap.dn_agl2size
+#define	db_agwidth	db_bmap.dn_agwidth
+#define	db_agheight	db_bmap.dn_agheight
+#define	db_agstart	db_bmap.dn_agstart
+#define	db_numag	db_bmap.dn_numag
+#define	db_maxlevel	db_bmap.dn_maxlevel
+#define	db_aglevel	db_bmap.dn_aglevel
+#define	db_agpref	db_bmap.dn_agpref
+#define	db_maxag	db_bmap.dn_maxag
+#define	db_maxfreebud	db_bmap.dn_maxfreebud
+#define	db_l2nbperpage	db_bmap.dn_l2nbperpage
+
+/*
+ * macros for various conversions needed by the allocators.
+ * blkstol2(), cntlz(), and cnttz() are operating system dependent functions.
+ */
+/* convert number of blocks to log2 number of blocks, rounding up to
+ * the next log2 value if blocks is not a l2 multiple.
+ */
+#define	BLKSTOL2(d)		(blkstol2(d))
+
+/* convert number of leafs to log2 leaf value */
+#define	NLSTOL2BSZ(n)		(31 - cntlz((n)) + BUDMIN)
+
+/* convert leaf index to log2 leaf value */
+#define	LITOL2BSZ(n,m,b)	((((n) == 0) ? (m) : cnttz((n))) + (b))
+
+/* convert a block number to a dmap control leaf index */
+#define BLKTOCTLLEAF(b,m)	\
+	(((b) & (((s64)1 << ((m) + L2LPERCTL)) - 1)) >> (m))
+
+/* convert log2 leaf value to buddy size */
+#define	BUDSIZE(s,m)		(1 << ((s) - (m)))
+
+/*
+ *	external references.
+ */
+extern int dbMount(struct inode *ipbmap);
+
+extern int dbUnmount(struct inode *ipbmap, int mounterror);
+
+extern int dbFree(struct inode *ipbmap, s64 blkno, s64 nblocks);
+
+extern int dbUpdatePMap(struct inode *ipbmap,
+			int free, s64 blkno, s64 nblocks, struct tblock * tblk);
+
+extern int dbNextAG(struct inode *ipbmap);
+
+extern int dbAlloc(struct inode *ipbmap, s64 hint, s64 nblocks, s64 * results);
+
+extern int dbReAlloc(struct inode *ipbmap,
+		     s64 blkno, s64 nblocks, s64 addnblocks, s64 * results);
+
+extern int dbSync(struct inode *ipbmap);
+extern int dbAllocBottomUp(struct inode *ip, s64 blkno, s64 nblocks);
+extern int dbExtendFS(struct inode *ipbmap, s64 blkno, s64 nblocks);
+extern void dbFinalizeBmap(struct inode *ipbmap);
+extern s64 dbMapFileSizeToMapSize(struct inode *ipbmap);
+extern s64 dbDiscardAG(struct inode *ip, int agno, s64 minlen);
+
+#endif				/* _H_JFS_DMAP */
diff --git a/fs/jfs/jfs_dtree.c b/fs/jfs/jfs_dtree.c
new file mode 100644
index 000000000..92b7c5334
--- /dev/null
+++ b/fs/jfs/jfs_dtree.c
@@ -0,0 +1,4264 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+
+/*
+ *	jfs_dtree.c: directory B+-tree manager
+ *
+ * B+-tree with variable length key directory:
+ *
+ * each directory page is structured as an array of 32-byte
+ * directory entry slots initialized as a freelist
+ * to avoid search/compaction of free space at insertion.
+ * when an entry is inserted, a number of slots are allocated
+ * from the freelist as required to store variable length data
+ * of the entry; when the entry is deleted, slots of the entry
+ * are returned to freelist.
+ *
+ * leaf entry stores full name as key and file serial number
+ * (aka inode number) as data.
+ * internal/router entry stores sufffix compressed name
+ * as key and simple extent descriptor as data.
+ *
+ * each directory page maintains a sorted entry index table
+ * which stores the start slot index of sorted entries
+ * to allow binary search on the table.
+ *
+ * directory starts as a root/leaf page in on-disk inode
+ * inline data area.
+ * when it becomes full, it starts a leaf of a external extent
+ * of length of 1 block. each time the first leaf becomes full,
+ * it is extended rather than split (its size is doubled),
+ * until its length becoms 4 KBytes, from then the extent is split
+ * with new 4 Kbyte extent when it becomes full
+ * to reduce external fragmentation of small directories.
+ *
+ * blah, blah, blah, for linear scan of directory in pieces by
+ * readdir().
+ *
+ *
+ *	case-insensitive directory file system
+ *
+ * names are stored in case-sensitive way in leaf entry.
+ * but stored, searched and compared in case-insensitive (uppercase) order
+ * (i.e., both search key and entry key are folded for search/compare):
+ * (note that case-sensitive order is BROKEN in storage, e.g.,
+ *  sensitive: Ad, aB, aC, aD -> insensitive: aB, aC, aD, Ad
+ *
+ *  entries which folds to the same key makes up a equivalent class
+ *  whose members are stored as contiguous cluster (may cross page boundary)
+ *  but whose order is arbitrary and acts as duplicate, e.g.,
+ *  abc, Abc, aBc, abC)
+ *
+ * once match is found at leaf, requires scan forward/backward
+ * either for, in case-insensitive search, duplicate
+ * or for, in case-sensitive search, for exact match
+ *
+ * router entry must be created/stored in case-insensitive way
+ * in internal entry:
+ * (right most key of left page and left most key of right page
+ * are folded, and its suffix compression is propagated as router
+ * key in parent)
+ * (e.g., if split occurs <abc> and <aBd>, <ABD> trather than <aB>
+ * should be made the router key for the split)
+ *
+ * case-insensitive search:
+ *
+ *	fold search key;
+ *
+ *	case-insensitive search of B-tree:
+ *	for internal entry, router key is already folded;
+ *	for leaf entry, fold the entry key before comparison.
+ *
+ *	if (leaf entry case-insensitive match found)
+ *		if (next entry satisfies case-insensitive match)
+ *			return EDUPLICATE;
+ *		if (prev entry satisfies case-insensitive match)
+ *			return EDUPLICATE;
+ *		return match;
+ *	else
+ *		return no match;
+ *
+ *	serialization:
+ * target directory inode lock is being held on entry/exit
+ * of all main directory service routines.
+ *
+ *	log based recovery:
+ */
+
+#include <linux/fs.h>
+#include <linux/quotaops.h>
+#include <linux/slab.h>
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_filsys.h"
+#include "jfs_metapage.h"
+#include "jfs_dmap.h"
+#include "jfs_unicode.h"
+#include "jfs_debug.h"
+
+/* dtree split parameter */
+struct dtsplit {
+	struct metapage *mp;
+	s16 index;
+	s16 nslot;
+	struct component_name *key;
+	ddata_t *data;
+	struct pxdlist *pxdlist;
+};
+
+#define DT_PAGE(IP, MP) BT_PAGE(IP, MP, dtpage_t, i_dtroot)
+
+/* get page buffer for specified block address */
+#define DT_GETPAGE(IP, BN, MP, SIZE, P, RC)				\
+do {									\
+	BT_GETPAGE(IP, BN, MP, dtpage_t, SIZE, P, RC, i_dtroot);	\
+	if (!(RC)) {							\
+		if (((P)->header.nextindex >				\
+		     (((BN) == 0) ? DTROOTMAXSLOT : (P)->header.maxslot)) || \
+		    ((BN) && ((P)->header.maxslot > DTPAGEMAXSLOT))) {	\
+			BT_PUTPAGE(MP);					\
+			jfs_error((IP)->i_sb,				\
+				  "DT_GETPAGE: dtree page corrupt\n");	\
+			MP = NULL;					\
+			RC = -EIO;					\
+		}							\
+	}								\
+} while (0)
+
+/* for consistency */
+#define DT_PUTPAGE(MP) BT_PUTPAGE(MP)
+
+#define DT_GETSEARCH(IP, LEAF, BN, MP, P, INDEX) \
+	BT_GETSEARCH(IP, LEAF, BN, MP, dtpage_t, P, INDEX, i_dtroot)
+
+/*
+ * forward references
+ */
+static int dtSplitUp(tid_t tid, struct inode *ip,
+		     struct dtsplit * split, struct btstack * btstack);
+
+static int dtSplitPage(tid_t tid, struct inode *ip, struct dtsplit * split,
+		       struct metapage ** rmpp, dtpage_t ** rpp, pxd_t * rxdp);
+
+static int dtExtendPage(tid_t tid, struct inode *ip,
+			struct dtsplit * split, struct btstack * btstack);
+
+static int dtSplitRoot(tid_t tid, struct inode *ip,
+		       struct dtsplit * split, struct metapage ** rmpp);
+
+static int dtDeleteUp(tid_t tid, struct inode *ip, struct metapage * fmp,
+		      dtpage_t * fp, struct btstack * btstack);
+
+static int dtRelink(tid_t tid, struct inode *ip, dtpage_t * p);
+
+static int dtReadFirst(struct inode *ip, struct btstack * btstack);
+
+static int dtReadNext(struct inode *ip,
+		      loff_t * offset, struct btstack * btstack);
+
+static int dtCompare(struct component_name * key, dtpage_t * p, int si);
+
+static int ciCompare(struct component_name * key, dtpage_t * p, int si,
+		     int flag);
+
+static void dtGetKey(dtpage_t * p, int i, struct component_name * key,
+		     int flag);
+
+static int ciGetLeafPrefixKey(dtpage_t * lp, int li, dtpage_t * rp,
+			      int ri, struct component_name * key, int flag);
+
+static void dtInsertEntry(dtpage_t * p, int index, struct component_name * key,
+			  ddata_t * data, struct dt_lock **);
+
+static void dtMoveEntry(dtpage_t * sp, int si, dtpage_t * dp,
+			struct dt_lock ** sdtlock, struct dt_lock ** ddtlock,
+			int do_index);
+
+static void dtDeleteEntry(dtpage_t * p, int fi, struct dt_lock ** dtlock);
+
+static void dtTruncateEntry(dtpage_t * p, int ti, struct dt_lock ** dtlock);
+
+static void dtLinelockFreelist(dtpage_t * p, int m, struct dt_lock ** dtlock);
+
+#define ciToUpper(c)	UniStrupr((c)->name)
+
+/*
+ *	read_index_page()
+ *
+ *	Reads a page of a directory's index table.
+ *	Having metadata mapped into the directory inode's address space
+ *	presents a multitude of problems.  We avoid this by mapping to
+ *	the absolute address space outside of the *_metapage routines
+ */
+static struct metapage *read_index_page(struct inode *inode, s64 blkno)
+{
+	int rc;
+	s64 xaddr;
+	int xflag;
+	s32 xlen;
+
+	rc = xtLookup(inode, blkno, 1, &xflag, &xaddr, &xlen, 1);
+	if (rc || (xaddr == 0))
+		return NULL;
+
+	return read_metapage(inode, xaddr, PSIZE, 1);
+}
+
+/*
+ *	get_index_page()
+ *
+ *	Same as get_index_page(), but get's a new page without reading
+ */
+static struct metapage *get_index_page(struct inode *inode, s64 blkno)
+{
+	int rc;
+	s64 xaddr;
+	int xflag;
+	s32 xlen;
+
+	rc = xtLookup(inode, blkno, 1, &xflag, &xaddr, &xlen, 1);
+	if (rc || (xaddr == 0))
+		return NULL;
+
+	return get_metapage(inode, xaddr, PSIZE, 1);
+}
+
+/*
+ *	find_index()
+ *
+ *	Returns dtree page containing directory table entry for specified
+ *	index and pointer to its entry.
+ *
+ *	mp must be released by caller.
+ */
+static struct dir_table_slot *find_index(struct inode *ip, u32 index,
+					 struct metapage ** mp, s64 *lblock)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	s64 blkno;
+	s64 offset;
+	int page_offset;
+	struct dir_table_slot *slot;
+	static int maxWarnings = 10;
+
+	if (index < 2) {
+		if (maxWarnings) {
+			jfs_warn("find_entry called with index = %d", index);
+			maxWarnings--;
+		}
+		return NULL;
+	}
+
+	if (index >= jfs_ip->next_index) {
+		jfs_warn("find_entry called with index >= next_index");
+		return NULL;
+	}
+
+	if (jfs_dirtable_inline(ip)) {
+		/*
+		 * Inline directory table
+		 */
+		*mp = NULL;
+		slot = &jfs_ip->i_dirtable[index - 2];
+	} else {
+		offset = (index - 2) * sizeof(struct dir_table_slot);
+		page_offset = offset & (PSIZE - 1);
+		blkno = ((offset + 1) >> L2PSIZE) <<
+		    JFS_SBI(ip->i_sb)->l2nbperpage;
+
+		if (*mp && (*lblock != blkno)) {
+			release_metapage(*mp);
+			*mp = NULL;
+		}
+		if (!(*mp)) {
+			*lblock = blkno;
+			*mp = read_index_page(ip, blkno);
+		}
+		if (!(*mp)) {
+			jfs_err("free_index: error reading directory table");
+			return NULL;
+		}
+
+		slot =
+		    (struct dir_table_slot *) ((char *) (*mp)->data +
+					       page_offset);
+	}
+	return slot;
+}
+
+static inline void lock_index(tid_t tid, struct inode *ip, struct metapage * mp,
+			      u32 index)
+{
+	struct tlock *tlck;
+	struct linelock *llck;
+	struct lv *lv;
+
+	tlck = txLock(tid, ip, mp, tlckDATA);
+	llck = (struct linelock *) tlck->lock;
+
+	if (llck->index >= llck->maxcnt)
+		llck = txLinelock(llck);
+	lv = &llck->lv[llck->index];
+
+	/*
+	 *	Linelock slot size is twice the size of directory table
+	 *	slot size.  512 entries per page.
+	 */
+	lv->offset = ((index - 2) & 511) >> 1;
+	lv->length = 1;
+	llck->index++;
+}
+
+/*
+ *	add_index()
+ *
+ *	Adds an entry to the directory index table.  This is used to provide
+ *	each directory entry with a persistent index in which to resume
+ *	directory traversals
+ */
+static u32 add_index(tid_t tid, struct inode *ip, s64 bn, int slot)
+{
+	struct super_block *sb = ip->i_sb;
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	u64 blkno;
+	struct dir_table_slot *dirtab_slot;
+	u32 index;
+	struct linelock *llck;
+	struct lv *lv;
+	struct metapage *mp;
+	s64 offset;
+	uint page_offset;
+	struct tlock *tlck;
+	s64 xaddr;
+
+	ASSERT(DO_INDEX(ip));
+
+	if (jfs_ip->next_index < 2) {
+		jfs_warn("add_index: next_index = %d.  Resetting!",
+			   jfs_ip->next_index);
+		jfs_ip->next_index = 2;
+	}
+
+	index = jfs_ip->next_index++;
+
+	if (index <= MAX_INLINE_DIRTABLE_ENTRY) {
+		/*
+		 * i_size reflects size of index table, or 8 bytes per entry.
+		 */
+		ip->i_size = (loff_t) (index - 1) << 3;
+
+		/*
+		 * dir table fits inline within inode
+		 */
+		dirtab_slot = &jfs_ip->i_dirtable[index-2];
+		dirtab_slot->flag = DIR_INDEX_VALID;
+		dirtab_slot->slot = slot;
+		DTSaddress(dirtab_slot, bn);
+
+		set_cflag(COMMIT_Dirtable, ip);
+
+		return index;
+	}
+	if (index == (MAX_INLINE_DIRTABLE_ENTRY + 1)) {
+		struct dir_table_slot temp_table[12];
+
+		/*
+		 * It's time to move the inline table to an external
+		 * page and begin to build the xtree
+		 */
+		if (dquot_alloc_block(ip, sbi->nbperpage))
+			goto clean_up;
+		if (dbAlloc(ip, 0, sbi->nbperpage, &xaddr)) {
+			dquot_free_block(ip, sbi->nbperpage);
+			goto clean_up;
+		}
+
+		/*
+		 * Save the table, we're going to overwrite it with the
+		 * xtree root
+		 */
+		memcpy(temp_table, &jfs_ip->i_dirtable, sizeof(temp_table));
+
+		/*
+		 * Initialize empty x-tree
+		 */
+		xtInitRoot(tid, ip);
+
+		/*
+		 * Add the first block to the xtree
+		 */
+		if (xtInsert(tid, ip, 0, 0, sbi->nbperpage, &xaddr, 0)) {
+			/* This really shouldn't fail */
+			jfs_warn("add_index: xtInsert failed!");
+			memcpy(&jfs_ip->i_dirtable, temp_table,
+			       sizeof (temp_table));
+			dbFree(ip, xaddr, sbi->nbperpage);
+			dquot_free_block(ip, sbi->nbperpage);
+			goto clean_up;
+		}
+		ip->i_size = PSIZE;
+
+		mp = get_index_page(ip, 0);
+		if (!mp) {
+			jfs_err("add_index: get_metapage failed!");
+			xtTruncate(tid, ip, 0, COMMIT_PWMAP);
+			memcpy(&jfs_ip->i_dirtable, temp_table,
+			       sizeof (temp_table));
+			goto clean_up;
+		}
+		tlck = txLock(tid, ip, mp, tlckDATA);
+		llck = (struct linelock *) & tlck->lock;
+		ASSERT(llck->index == 0);
+		lv = &llck->lv[0];
+
+		lv->offset = 0;
+		lv->length = 6;	/* tlckDATA slot size is 16 bytes */
+		llck->index++;
+
+		memcpy(mp->data, temp_table, sizeof(temp_table));
+
+		mark_metapage_dirty(mp);
+		release_metapage(mp);
+
+		/*
+		 * Logging is now directed by xtree tlocks
+		 */
+		clear_cflag(COMMIT_Dirtable, ip);
+	}
+
+	offset = (index - 2) * sizeof(struct dir_table_slot);
+	page_offset = offset & (PSIZE - 1);
+	blkno = ((offset + 1) >> L2PSIZE) << sbi->l2nbperpage;
+	if (page_offset == 0) {
+		/*
+		 * This will be the beginning of a new page
+		 */
+		xaddr = 0;
+		if (xtInsert(tid, ip, 0, blkno, sbi->nbperpage, &xaddr, 0)) {
+			jfs_warn("add_index: xtInsert failed!");
+			goto clean_up;
+		}
+		ip->i_size += PSIZE;
+
+		if ((mp = get_index_page(ip, blkno)))
+			memset(mp->data, 0, PSIZE);	/* Just looks better */
+		else
+			xtTruncate(tid, ip, offset, COMMIT_PWMAP);
+	} else
+		mp = read_index_page(ip, blkno);
+
+	if (!mp) {
+		jfs_err("add_index: get/read_metapage failed!");
+		goto clean_up;
+	}
+
+	lock_index(tid, ip, mp, index);
+
+	dirtab_slot =
+	    (struct dir_table_slot *) ((char *) mp->data + page_offset);
+	dirtab_slot->flag = DIR_INDEX_VALID;
+	dirtab_slot->slot = slot;
+	DTSaddress(dirtab_slot, bn);
+
+	mark_metapage_dirty(mp);
+	release_metapage(mp);
+
+	return index;
+
+      clean_up:
+
+	jfs_ip->next_index--;
+
+	return 0;
+}
+
+/*
+ *	free_index()
+ *
+ *	Marks an entry to the directory index table as free.
+ */
+static void free_index(tid_t tid, struct inode *ip, u32 index, u32 next)
+{
+	struct dir_table_slot *dirtab_slot;
+	s64 lblock;
+	struct metapage *mp = NULL;
+
+	dirtab_slot = find_index(ip, index, &mp, &lblock);
+
+	if (!dirtab_slot)
+		return;
+
+	dirtab_slot->flag = DIR_INDEX_FREE;
+	dirtab_slot->slot = dirtab_slot->addr1 = 0;
+	dirtab_slot->addr2 = cpu_to_le32(next);
+
+	if (mp) {
+		lock_index(tid, ip, mp, index);
+		mark_metapage_dirty(mp);
+		release_metapage(mp);
+	} else
+		set_cflag(COMMIT_Dirtable, ip);
+}
+
+/*
+ *	modify_index()
+ *
+ *	Changes an entry in the directory index table
+ */
+static void modify_index(tid_t tid, struct inode *ip, u32 index, s64 bn,
+			 int slot, struct metapage ** mp, s64 *lblock)
+{
+	struct dir_table_slot *dirtab_slot;
+
+	dirtab_slot = find_index(ip, index, mp, lblock);
+
+	if (!dirtab_slot)
+		return;
+
+	DTSaddress(dirtab_slot, bn);
+	dirtab_slot->slot = slot;
+
+	if (*mp) {
+		lock_index(tid, ip, *mp, index);
+		mark_metapage_dirty(*mp);
+	} else
+		set_cflag(COMMIT_Dirtable, ip);
+}
+
+/*
+ *	read_index()
+ *
+ *	reads a directory table slot
+ */
+static int read_index(struct inode *ip, u32 index,
+		     struct dir_table_slot * dirtab_slot)
+{
+	s64 lblock;
+	struct metapage *mp = NULL;
+	struct dir_table_slot *slot;
+
+	slot = find_index(ip, index, &mp, &lblock);
+	if (!slot) {
+		return -EIO;
+	}
+
+	memcpy(dirtab_slot, slot, sizeof(struct dir_table_slot));
+
+	if (mp)
+		release_metapage(mp);
+
+	return 0;
+}
+
+/*
+ *	dtSearch()
+ *
+ * function:
+ *	Search for the entry with specified key
+ *
+ * parameter:
+ *
+ * return: 0 - search result on stack, leaf page pinned;
+ *	   errno - I/O error
+ */
+int dtSearch(struct inode *ip, struct component_name * key, ino_t * data,
+	     struct btstack * btstack, int flag)
+{
+	int rc = 0;
+	int cmp = 1;		/* init for empty page */
+	s64 bn;
+	struct metapage *mp;
+	dtpage_t *p;
+	s8 *stbl;
+	int base, index, lim;
+	struct btframe *btsp;
+	pxd_t *pxd;
+	int psize = 288;	/* initial in-line directory */
+	ino_t inumber;
+	struct component_name ciKey;
+	struct super_block *sb = ip->i_sb;
+
+	ciKey.name = kmalloc_array(JFS_NAME_MAX + 1, sizeof(wchar_t),
+				   GFP_NOFS);
+	if (!ciKey.name) {
+		rc = -ENOMEM;
+		goto dtSearch_Exit2;
+	}
+
+
+	/* uppercase search key for c-i directory */
+	UniStrcpy(ciKey.name, key->name);
+	ciKey.namlen = key->namlen;
+
+	/* only uppercase if case-insensitive support is on */
+	if ((JFS_SBI(sb)->mntflag & JFS_OS2) == JFS_OS2) {
+		ciToUpper(&ciKey);
+	}
+	BT_CLR(btstack);	/* reset stack */
+
+	/* init level count for max pages to split */
+	btstack->nsplit = 1;
+
+	/*
+	 *	search down tree from root:
+	 *
+	 * between two consecutive entries of <Ki, Pi> and <Kj, Pj> of
+	 * internal page, child page Pi contains entry with k, Ki <= K < Kj.
+	 *
+	 * if entry with search key K is not found
+	 * internal page search find the entry with largest key Ki
+	 * less than K which point to the child page to search;
+	 * leaf page search find the entry with smallest key Kj
+	 * greater than K so that the returned index is the position of
+	 * the entry to be shifted right for insertion of new entry.
+	 * for empty tree, search key is greater than any key of the tree.
+	 *
+	 * by convention, root bn = 0.
+	 */
+	for (bn = 0;;) {
+		/* get/pin the page to search */
+		DT_GETPAGE(ip, bn, mp, psize, p, rc);
+		if (rc)
+			goto dtSearch_Exit1;
+
+		/* get sorted entry table of the page */
+		stbl = DT_GETSTBL(p);
+
+		/*
+		 * binary search with search key K on the current page.
+		 */
+		for (base = 0, lim = p->header.nextindex; lim; lim >>= 1) {
+			index = base + (lim >> 1);
+
+			if (p->header.flag & BT_LEAF) {
+				/* uppercase leaf name to compare */
+				cmp =
+				    ciCompare(&ciKey, p, stbl[index],
+					      JFS_SBI(sb)->mntflag);
+			} else {
+				/* router key is in uppercase */
+
+				cmp = dtCompare(&ciKey, p, stbl[index]);
+
+
+			}
+			if (cmp == 0) {
+				/*
+				 *	search hit
+				 */
+				/* search hit - leaf page:
+				 * return the entry found
+				 */
+				if (p->header.flag & BT_LEAF) {
+					inumber = le32_to_cpu(
+			((struct ldtentry *) & p->slot[stbl[index]])->inumber);
+
+					/*
+					 * search for JFS_LOOKUP
+					 */
+					if (flag == JFS_LOOKUP) {
+						*data = inumber;
+						rc = 0;
+						goto out;
+					}
+
+					/*
+					 * search for JFS_CREATE
+					 */
+					if (flag == JFS_CREATE) {
+						*data = inumber;
+						rc = -EEXIST;
+						goto out;
+					}
+
+					/*
+					 * search for JFS_REMOVE or JFS_RENAME
+					 */
+					if ((flag == JFS_REMOVE ||
+					     flag == JFS_RENAME) &&
+					    *data != inumber) {
+						rc = -ESTALE;
+						goto out;
+					}
+
+					/*
+					 * JFS_REMOVE|JFS_FINDDIR|JFS_RENAME
+					 */
+					/* save search result */
+					*data = inumber;
+					btsp = btstack->top;
+					btsp->bn = bn;
+					btsp->index = index;
+					btsp->mp = mp;
+
+					rc = 0;
+					goto dtSearch_Exit1;
+				}
+
+				/* search hit - internal page:
+				 * descend/search its child page
+				 */
+				goto getChild;
+			}
+
+			if (cmp > 0) {
+				base = index + 1;
+				--lim;
+			}
+		}
+
+		/*
+		 *	search miss
+		 *
+		 * base is the smallest index with key (Kj) greater than
+		 * search key (K) and may be zero or (maxindex + 1) index.
+		 */
+		/*
+		 * search miss - leaf page
+		 *
+		 * return location of entry (base) where new entry with
+		 * search key K is to be inserted.
+		 */
+		if (p->header.flag & BT_LEAF) {
+			/*
+			 * search for JFS_LOOKUP, JFS_REMOVE, or JFS_RENAME
+			 */
+			if (flag == JFS_LOOKUP || flag == JFS_REMOVE ||
+			    flag == JFS_RENAME) {
+				rc = -ENOENT;
+				goto out;
+			}
+
+			/*
+			 * search for JFS_CREATE|JFS_FINDDIR:
+			 *
+			 * save search result
+			 */
+			*data = 0;
+			btsp = btstack->top;
+			btsp->bn = bn;
+			btsp->index = base;
+			btsp->mp = mp;
+
+			rc = 0;
+			goto dtSearch_Exit1;
+		}
+
+		/*
+		 * search miss - internal page
+		 *
+		 * if base is non-zero, decrement base by one to get the parent
+		 * entry of the child page to search.
+		 */
+		index = base ? base - 1 : base;
+
+		/*
+		 * go down to child page
+		 */
+	      getChild:
+		/* update max. number of pages to split */
+		if (BT_STACK_FULL(btstack)) {
+			/* Something's corrupted, mark filesystem dirty so
+			 * chkdsk will fix it.
+			 */
+			jfs_error(sb, "stack overrun!\n");
+			BT_STACK_DUMP(btstack);
+			rc = -EIO;
+			goto out;
+		}
+		btstack->nsplit++;
+
+		/* push (bn, index) of the parent page/entry */
+		BT_PUSH(btstack, bn, index);
+
+		/* get the child page block number */
+		pxd = (pxd_t *) & p->slot[stbl[index]];
+		bn = addressPXD(pxd);
+		psize = lengthPXD(pxd) << JFS_SBI(ip->i_sb)->l2bsize;
+
+		/* unpin the parent page */
+		DT_PUTPAGE(mp);
+	}
+
+      out:
+	DT_PUTPAGE(mp);
+
+      dtSearch_Exit1:
+
+	kfree(ciKey.name);
+
+      dtSearch_Exit2:
+
+	return rc;
+}
+
+
+/*
+ *	dtInsert()
+ *
+ * function: insert an entry to directory tree
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ *	   errno - failure;
+ */
+int dtInsert(tid_t tid, struct inode *ip,
+	 struct component_name * name, ino_t * fsn, struct btstack * btstack)
+{
+	int rc = 0;
+	struct metapage *mp;	/* meta-page buffer */
+	dtpage_t *p;		/* base B+-tree index page */
+	s64 bn;
+	int index;
+	struct dtsplit split;	/* split information */
+	ddata_t data;
+	struct dt_lock *dtlck;
+	int n;
+	struct tlock *tlck;
+	struct lv *lv;
+
+	/*
+	 *	retrieve search result
+	 *
+	 * dtSearch() returns (leaf page pinned, index at which to insert).
+	 * n.b. dtSearch() may return index of (maxindex + 1) of
+	 * the full page.
+	 */
+	DT_GETSEARCH(ip, btstack->top, bn, mp, p, index);
+
+	/*
+	 *	insert entry for new key
+	 */
+	if (DO_INDEX(ip)) {
+		if (JFS_IP(ip)->next_index == DIREND) {
+			DT_PUTPAGE(mp);
+			return -EMLINK;
+		}
+		n = NDTLEAF(name->namlen);
+		data.leaf.tid = tid;
+		data.leaf.ip = ip;
+	} else {
+		n = NDTLEAF_LEGACY(name->namlen);
+		data.leaf.ip = NULL;	/* signifies legacy directory format */
+	}
+	data.leaf.ino = *fsn;
+
+	/*
+	 *	leaf page does not have enough room for new entry:
+	 *
+	 *	extend/split the leaf page;
+	 *
+	 * dtSplitUp() will insert the entry and unpin the leaf page.
+	 */
+	if (n > p->header.freecnt) {
+		split.mp = mp;
+		split.index = index;
+		split.nslot = n;
+		split.key = name;
+		split.data = &data;
+		rc = dtSplitUp(tid, ip, &split, btstack);
+		return rc;
+	}
+
+	/*
+	 *	leaf page does have enough room for new entry:
+	 *
+	 *	insert the new data entry into the leaf page;
+	 */
+	BT_MARK_DIRTY(mp, ip);
+	/*
+	 * acquire a transaction lock on the leaf page
+	 */
+	tlck = txLock(tid, ip, mp, tlckDTREE | tlckENTRY);
+	dtlck = (struct dt_lock *) & tlck->lock;
+	ASSERT(dtlck->index == 0);
+	lv = & dtlck->lv[0];
+
+	/* linelock header */
+	lv->offset = 0;
+	lv->length = 1;
+	dtlck->index++;
+
+	dtInsertEntry(p, index, name, &data, &dtlck);
+
+	/* linelock stbl of non-root leaf page */
+	if (!(p->header.flag & BT_ROOT)) {
+		if (dtlck->index >= dtlck->maxcnt)
+			dtlck = (struct dt_lock *) txLinelock(dtlck);
+		lv = & dtlck->lv[dtlck->index];
+		n = index >> L2DTSLOTSIZE;
+		lv->offset = p->header.stblindex + n;
+		lv->length =
+		    ((p->header.nextindex - 1) >> L2DTSLOTSIZE) - n + 1;
+		dtlck->index++;
+	}
+
+	/* unpin the leaf page */
+	DT_PUTPAGE(mp);
+
+	return 0;
+}
+
+
+/*
+ *	dtSplitUp()
+ *
+ * function: propagate insertion bottom up;
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ *	   errno - failure;
+ *	leaf page unpinned;
+ */
+static int dtSplitUp(tid_t tid,
+	  struct inode *ip, struct dtsplit * split, struct btstack * btstack)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+	int rc = 0;
+	struct metapage *smp;
+	dtpage_t *sp;		/* split page */
+	struct metapage *rmp;
+	dtpage_t *rp;		/* new right page split from sp */
+	pxd_t rpxd;		/* new right page extent descriptor */
+	struct metapage *lmp;
+	dtpage_t *lp;		/* left child page */
+	int skip;		/* index of entry of insertion */
+	struct btframe *parent;	/* parent page entry on traverse stack */
+	s64 xaddr, nxaddr;
+	int xlen, xsize;
+	struct pxdlist pxdlist;
+	pxd_t *pxd;
+	struct component_name key = { 0, NULL };
+	ddata_t *data = split->data;
+	int n;
+	struct dt_lock *dtlck;
+	struct tlock *tlck;
+	struct lv *lv;
+	int quota_allocation = 0;
+
+	/* get split page */
+	smp = split->mp;
+	sp = DT_PAGE(ip, smp);
+
+	key.name = kmalloc_array(JFS_NAME_MAX + 2, sizeof(wchar_t), GFP_NOFS);
+	if (!key.name) {
+		DT_PUTPAGE(smp);
+		rc = -ENOMEM;
+		goto dtSplitUp_Exit;
+	}
+
+	/*
+	 *	split leaf page
+	 *
+	 * The split routines insert the new entry, and
+	 * acquire txLock as appropriate.
+	 */
+	/*
+	 *	split root leaf page:
+	 */
+	if (sp->header.flag & BT_ROOT) {
+		/*
+		 * allocate a single extent child page
+		 */
+		xlen = 1;
+		n = sbi->bsize >> L2DTSLOTSIZE;
+		n -= (n + 31) >> L2DTSLOTSIZE;	/* stbl size */
+		n -= DTROOTMAXSLOT - sp->header.freecnt; /* header + entries */
+		if (n <= split->nslot)
+			xlen++;
+		if ((rc = dbAlloc(ip, 0, (s64) xlen, &xaddr))) {
+			DT_PUTPAGE(smp);
+			goto freeKeyName;
+		}
+
+		pxdlist.maxnpxd = 1;
+		pxdlist.npxd = 0;
+		pxd = &pxdlist.pxd[0];
+		PXDaddress(pxd, xaddr);
+		PXDlength(pxd, xlen);
+		split->pxdlist = &pxdlist;
+		rc = dtSplitRoot(tid, ip, split, &rmp);
+
+		if (rc)
+			dbFree(ip, xaddr, xlen);
+		else
+			DT_PUTPAGE(rmp);
+
+		DT_PUTPAGE(smp);
+
+		if (!DO_INDEX(ip))
+			ip->i_size = xlen << sbi->l2bsize;
+
+		goto freeKeyName;
+	}
+
+	/*
+	 *	extend first leaf page
+	 *
+	 * extend the 1st extent if less than buffer page size
+	 * (dtExtendPage() reurns leaf page unpinned)
+	 */
+	pxd = &sp->header.self;
+	xlen = lengthPXD(pxd);
+	xsize = xlen << sbi->l2bsize;
+	if (xsize < PSIZE) {
+		xaddr = addressPXD(pxd);
+		n = xsize >> L2DTSLOTSIZE;
+		n -= (n + 31) >> L2DTSLOTSIZE;	/* stbl size */
+		if ((n + sp->header.freecnt) <= split->nslot)
+			n = xlen + (xlen << 1);
+		else
+			n = xlen;
+
+		/* Allocate blocks to quota. */
+		rc = dquot_alloc_block(ip, n);
+		if (rc)
+			goto extendOut;
+		quota_allocation += n;
+
+		if ((rc = dbReAlloc(sbi->ipbmap, xaddr, (s64) xlen,
+				    (s64) n, &nxaddr)))
+			goto extendOut;
+
+		pxdlist.maxnpxd = 1;
+		pxdlist.npxd = 0;
+		pxd = &pxdlist.pxd[0];
+		PXDaddress(pxd, nxaddr);
+		PXDlength(pxd, xlen + n);
+		split->pxdlist = &pxdlist;
+		if ((rc = dtExtendPage(tid, ip, split, btstack))) {
+			nxaddr = addressPXD(pxd);
+			if (xaddr != nxaddr) {
+				/* free relocated extent */
+				xlen = lengthPXD(pxd);
+				dbFree(ip, nxaddr, (s64) xlen);
+			} else {
+				/* free extended delta */
+				xlen = lengthPXD(pxd) - n;
+				xaddr = addressPXD(pxd) + xlen;
+				dbFree(ip, xaddr, (s64) n);
+			}
+		} else if (!DO_INDEX(ip))
+			ip->i_size = lengthPXD(pxd) << sbi->l2bsize;
+
+
+	      extendOut:
+		DT_PUTPAGE(smp);
+		goto freeKeyName;
+	}
+
+	/*
+	 *	split leaf page <sp> into <sp> and a new right page <rp>.
+	 *
+	 * return <rp> pinned and its extent descriptor <rpxd>
+	 */
+	/*
+	 * allocate new directory page extent and
+	 * new index page(s) to cover page split(s)
+	 *
+	 * allocation hint: ?
+	 */
+	n = btstack->nsplit;
+	pxdlist.maxnpxd = pxdlist.npxd = 0;
+	xlen = sbi->nbperpage;
+	for (pxd = pxdlist.pxd; n > 0; n--, pxd++) {
+		if ((rc = dbAlloc(ip, 0, (s64) xlen, &xaddr)) == 0) {
+			PXDaddress(pxd, xaddr);
+			PXDlength(pxd, xlen);
+			pxdlist.maxnpxd++;
+			continue;
+		}
+
+		DT_PUTPAGE(smp);
+
+		/* undo allocation */
+		goto splitOut;
+	}
+
+	split->pxdlist = &pxdlist;
+	if ((rc = dtSplitPage(tid, ip, split, &rmp, &rp, &rpxd))) {
+		DT_PUTPAGE(smp);
+
+		/* undo allocation */
+		goto splitOut;
+	}
+
+	if (!DO_INDEX(ip))
+		ip->i_size += PSIZE;
+
+	/*
+	 * propagate up the router entry for the leaf page just split
+	 *
+	 * insert a router entry for the new page into the parent page,
+	 * propagate the insert/split up the tree by walking back the stack
+	 * of (bn of parent page, index of child page entry in parent page)
+	 * that were traversed during the search for the page that split.
+	 *
+	 * the propagation of insert/split up the tree stops if the root
+	 * splits or the page inserted into doesn't have to split to hold
+	 * the new entry.
+	 *
+	 * the parent entry for the split page remains the same, and
+	 * a new entry is inserted at its right with the first key and
+	 * block number of the new right page.
+	 *
+	 * There are a maximum of 4 pages pinned at any time:
+	 * two children, left parent and right parent (when the parent splits).
+	 * keep the child pages pinned while working on the parent.
+	 * make sure that all pins are released at exit.
+	 */
+	while ((parent = BT_POP(btstack)) != NULL) {
+		/* parent page specified by stack frame <parent> */
+
+		/* keep current child pages (<lp>, <rp>) pinned */
+		lmp = smp;
+		lp = sp;
+
+		/*
+		 * insert router entry in parent for new right child page <rp>
+		 */
+		/* get the parent page <sp> */
+		DT_GETPAGE(ip, parent->bn, smp, PSIZE, sp, rc);
+		if (rc) {
+			DT_PUTPAGE(lmp);
+			DT_PUTPAGE(rmp);
+			goto splitOut;
+		}
+
+		/*
+		 * The new key entry goes ONE AFTER the index of parent entry,
+		 * because the split was to the right.
+		 */
+		skip = parent->index + 1;
+
+		/*
+		 * compute the key for the router entry
+		 *
+		 * key suffix compression:
+		 * for internal pages that have leaf pages as children,
+		 * retain only what's needed to distinguish between
+		 * the new entry and the entry on the page to its left.
+		 * If the keys compare equal, retain the entire key.
+		 *
+		 * note that compression is performed only at computing
+		 * router key at the lowest internal level.
+		 * further compression of the key between pairs of higher
+		 * level internal pages loses too much information and
+		 * the search may fail.
+		 * (e.g., two adjacent leaf pages of {a, ..., x} {xx, ...,}
+		 * results in two adjacent parent entries (a)(xx).
+		 * if split occurs between these two entries, and
+		 * if compression is applied, the router key of parent entry
+		 * of right page (x) will divert search for x into right
+		 * subtree and miss x in the left subtree.)
+		 *
+		 * the entire key must be retained for the next-to-leftmost
+		 * internal key at any level of the tree, or search may fail
+		 * (e.g., ?)
+		 */
+		switch (rp->header.flag & BT_TYPE) {
+		case BT_LEAF:
+			/*
+			 * compute the length of prefix for suffix compression
+			 * between last entry of left page and first entry
+			 * of right page
+			 */
+			if ((sp->header.flag & BT_ROOT && skip > 1) ||
+			    sp->header.prev != 0 || skip > 1) {
+				/* compute uppercase router prefix key */
+				rc = ciGetLeafPrefixKey(lp,
+							lp->header.nextindex-1,
+							rp, 0, &key,
+							sbi->mntflag);
+				if (rc) {
+					DT_PUTPAGE(lmp);
+					DT_PUTPAGE(rmp);
+					DT_PUTPAGE(smp);
+					goto splitOut;
+				}
+			} else {
+				/* next to leftmost entry of
+				   lowest internal level */
+
+				/* compute uppercase router key */
+				dtGetKey(rp, 0, &key, sbi->mntflag);
+				key.name[key.namlen] = 0;
+
+				if ((sbi->mntflag & JFS_OS2) == JFS_OS2)
+					ciToUpper(&key);
+			}
+
+			n = NDTINTERNAL(key.namlen);
+			break;
+
+		case BT_INTERNAL:
+			dtGetKey(rp, 0, &key, sbi->mntflag);
+			n = NDTINTERNAL(key.namlen);
+			break;
+
+		default:
+			jfs_err("dtSplitUp(): UFO!");
+			break;
+		}
+
+		/* unpin left child page */
+		DT_PUTPAGE(lmp);
+
+		/*
+		 * compute the data for the router entry
+		 */
+		data->xd = rpxd;	/* child page xd */
+
+		/*
+		 * parent page is full - split the parent page
+		 */
+		if (n > sp->header.freecnt) {
+			/* init for parent page split */
+			split->mp = smp;
+			split->index = skip;	/* index at insert */
+			split->nslot = n;
+			split->key = &key;
+			/* split->data = data; */
+
+			/* unpin right child page */
+			DT_PUTPAGE(rmp);
+
+			/* The split routines insert the new entry,
+			 * acquire txLock as appropriate.
+			 * return <rp> pinned and its block number <rbn>.
+			 */
+			rc = (sp->header.flag & BT_ROOT) ?
+			    dtSplitRoot(tid, ip, split, &rmp) :
+			    dtSplitPage(tid, ip, split, &rmp, &rp, &rpxd);
+			if (rc) {
+				DT_PUTPAGE(smp);
+				goto splitOut;
+			}
+
+			/* smp and rmp are pinned */
+		}
+		/*
+		 * parent page is not full - insert router entry in parent page
+		 */
+		else {
+			BT_MARK_DIRTY(smp, ip);
+			/*
+			 * acquire a transaction lock on the parent page
+			 */
+			tlck = txLock(tid, ip, smp, tlckDTREE | tlckENTRY);
+			dtlck = (struct dt_lock *) & tlck->lock;
+			ASSERT(dtlck->index == 0);
+			lv = & dtlck->lv[0];
+
+			/* linelock header */
+			lv->offset = 0;
+			lv->length = 1;
+			dtlck->index++;
+
+			/* linelock stbl of non-root parent page */
+			if (!(sp->header.flag & BT_ROOT)) {
+				lv++;
+				n = skip >> L2DTSLOTSIZE;
+				lv->offset = sp->header.stblindex + n;
+				lv->length =
+				    ((sp->header.nextindex -
+				      1) >> L2DTSLOTSIZE) - n + 1;
+				dtlck->index++;
+			}
+
+			dtInsertEntry(sp, skip, &key, data, &dtlck);
+
+			/* exit propagate up */
+			break;
+		}
+	}
+
+	/* unpin current split and its right page */
+	DT_PUTPAGE(smp);
+	DT_PUTPAGE(rmp);
+
+	/*
+	 * free remaining extents allocated for split
+	 */
+      splitOut:
+	n = pxdlist.npxd;
+	pxd = &pxdlist.pxd[n];
+	for (; n < pxdlist.maxnpxd; n++, pxd++)
+		dbFree(ip, addressPXD(pxd), (s64) lengthPXD(pxd));
+
+      freeKeyName:
+	kfree(key.name);
+
+	/* Rollback quota allocation */
+	if (rc && quota_allocation)
+		dquot_free_block(ip, quota_allocation);
+
+      dtSplitUp_Exit:
+
+	return rc;
+}
+
+
+/*
+ *	dtSplitPage()
+ *
+ * function: Split a non-root page of a btree.
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ *	   errno - failure;
+ *	return split and new page pinned;
+ */
+static int dtSplitPage(tid_t tid, struct inode *ip, struct dtsplit * split,
+	    struct metapage ** rmpp, dtpage_t ** rpp, pxd_t * rpxdp)
+{
+	int rc = 0;
+	struct metapage *smp;
+	dtpage_t *sp;
+	struct metapage *rmp;
+	dtpage_t *rp;		/* new right page allocated */
+	s64 rbn;		/* new right page block number */
+	struct metapage *mp;
+	dtpage_t *p;
+	s64 nextbn;
+	struct pxdlist *pxdlist;
+	pxd_t *pxd;
+	int skip, nextindex, half, left, nxt, off, si;
+	struct ldtentry *ldtentry;
+	struct idtentry *idtentry;
+	u8 *stbl;
+	struct dtslot *f;
+	int fsi, stblsize;
+	int n;
+	struct dt_lock *sdtlck, *rdtlck;
+	struct tlock *tlck;
+	struct dt_lock *dtlck;
+	struct lv *slv, *rlv, *lv;
+
+	/* get split page */
+	smp = split->mp;
+	sp = DT_PAGE(ip, smp);
+
+	/*
+	 * allocate the new right page for the split
+	 */
+	pxdlist = split->pxdlist;
+	pxd = &pxdlist->pxd[pxdlist->npxd];
+	pxdlist->npxd++;
+	rbn = addressPXD(pxd);
+	rmp = get_metapage(ip, rbn, PSIZE, 1);
+	if (rmp == NULL)
+		return -EIO;
+
+	/* Allocate blocks to quota. */
+	rc = dquot_alloc_block(ip, lengthPXD(pxd));
+	if (rc) {
+		release_metapage(rmp);
+		return rc;
+	}
+
+	jfs_info("dtSplitPage: ip:0x%p smp:0x%p rmp:0x%p", ip, smp, rmp);
+
+	BT_MARK_DIRTY(rmp, ip);
+	/*
+	 * acquire a transaction lock on the new right page
+	 */
+	tlck = txLock(tid, ip, rmp, tlckDTREE | tlckNEW);
+	rdtlck = (struct dt_lock *) & tlck->lock;
+
+	rp = (dtpage_t *) rmp->data;
+	*rpp = rp;
+	rp->header.self = *pxd;
+
+	BT_MARK_DIRTY(smp, ip);
+	/*
+	 * acquire a transaction lock on the split page
+	 *
+	 * action:
+	 */
+	tlck = txLock(tid, ip, smp, tlckDTREE | tlckENTRY);
+	sdtlck = (struct dt_lock *) & tlck->lock;
+
+	/* linelock header of split page */
+	ASSERT(sdtlck->index == 0);
+	slv = & sdtlck->lv[0];
+	slv->offset = 0;
+	slv->length = 1;
+	sdtlck->index++;
+
+	/*
+	 * initialize/update sibling pointers between sp and rp
+	 */
+	nextbn = le64_to_cpu(sp->header.next);
+	rp->header.next = cpu_to_le64(nextbn);
+	rp->header.prev = cpu_to_le64(addressPXD(&sp->header.self));
+	sp->header.next = cpu_to_le64(rbn);
+
+	/*
+	 * initialize new right page
+	 */
+	rp->header.flag = sp->header.flag;
+
+	/* compute sorted entry table at start of extent data area */
+	rp->header.nextindex = 0;
+	rp->header.stblindex = 1;
+
+	n = PSIZE >> L2DTSLOTSIZE;
+	rp->header.maxslot = n;
+	stblsize = (n + 31) >> L2DTSLOTSIZE;	/* in unit of slot */
+
+	/* init freelist */
+	fsi = rp->header.stblindex + stblsize;
+	rp->header.freelist = fsi;
+	rp->header.freecnt = rp->header.maxslot - fsi;
+
+	/*
+	 *	sequential append at tail: append without split
+	 *
+	 * If splitting the last page on a level because of appending
+	 * a entry to it (skip is maxentry), it's likely that the access is
+	 * sequential. Adding an empty page on the side of the level is less
+	 * work and can push the fill factor much higher than normal.
+	 * If we're wrong it's no big deal, we'll just do the split the right
+	 * way next time.
+	 * (It may look like it's equally easy to do a similar hack for
+	 * reverse sorted data, that is, split the tree left,
+	 * but it's not. Be my guest.)
+	 */
+	if (nextbn == 0 && split->index == sp->header.nextindex) {
+		/* linelock header + stbl (first slot) of new page */
+		rlv = & rdtlck->lv[rdtlck->index];
+		rlv->offset = 0;
+		rlv->length = 2;
+		rdtlck->index++;
+
+		/*
+		 * initialize freelist of new right page
+		 */
+		f = &rp->slot[fsi];
+		for (fsi++; fsi < rp->header.maxslot; f++, fsi++)
+			f->next = fsi;
+		f->next = -1;
+
+		/* insert entry at the first entry of the new right page */
+		dtInsertEntry(rp, 0, split->key, split->data, &rdtlck);
+
+		goto out;
+	}
+
+	/*
+	 *	non-sequential insert (at possibly middle page)
+	 */
+
+	/*
+	 * update prev pointer of previous right sibling page;
+	 */
+	if (nextbn != 0) {
+		DT_GETPAGE(ip, nextbn, mp, PSIZE, p, rc);
+		if (rc) {
+			discard_metapage(rmp);
+			return rc;
+		}
+
+		BT_MARK_DIRTY(mp, ip);
+		/*
+		 * acquire a transaction lock on the next page
+		 */
+		tlck = txLock(tid, ip, mp, tlckDTREE | tlckRELINK);
+		jfs_info("dtSplitPage: tlck = 0x%p, ip = 0x%p, mp=0x%p",
+			tlck, ip, mp);
+		dtlck = (struct dt_lock *) & tlck->lock;
+
+		/* linelock header of previous right sibling page */
+		lv = & dtlck->lv[dtlck->index];
+		lv->offset = 0;
+		lv->length = 1;
+		dtlck->index++;
+
+		p->header.prev = cpu_to_le64(rbn);
+
+		DT_PUTPAGE(mp);
+	}
+
+	/*
+	 * split the data between the split and right pages.
+	 */
+	skip = split->index;
+	half = (PSIZE >> L2DTSLOTSIZE) >> 1;	/* swag */
+	left = 0;
+
+	/*
+	 *	compute fill factor for split pages
+	 *
+	 * <nxt> traces the next entry to move to rp
+	 * <off> traces the next entry to stay in sp
+	 */
+	stbl = (u8 *) & sp->slot[sp->header.stblindex];
+	nextindex = sp->header.nextindex;
+	for (nxt = off = 0; nxt < nextindex; ++off) {
+		if (off == skip)
+			/* check for fill factor with new entry size */
+			n = split->nslot;
+		else {
+			si = stbl[nxt];
+			switch (sp->header.flag & BT_TYPE) {
+			case BT_LEAF:
+				ldtentry = (struct ldtentry *) & sp->slot[si];
+				if (DO_INDEX(ip))
+					n = NDTLEAF(ldtentry->namlen);
+				else
+					n = NDTLEAF_LEGACY(ldtentry->
+							   namlen);
+				break;
+
+			case BT_INTERNAL:
+				idtentry = (struct idtentry *) & sp->slot[si];
+				n = NDTINTERNAL(idtentry->namlen);
+				break;
+
+			default:
+				break;
+			}
+
+			++nxt;	/* advance to next entry to move in sp */
+		}
+
+		left += n;
+		if (left >= half)
+			break;
+	}
+
+	/* <nxt> poins to the 1st entry to move */
+
+	/*
+	 *	move entries to right page
+	 *
+	 * dtMoveEntry() initializes rp and reserves entry for insertion
+	 *
+	 * split page moved out entries are linelocked;
+	 * new/right page moved in entries are linelocked;
+	 */
+	/* linelock header + stbl of new right page */
+	rlv = & rdtlck->lv[rdtlck->index];
+	rlv->offset = 0;
+	rlv->length = 5;
+	rdtlck->index++;
+
+	dtMoveEntry(sp, nxt, rp, &sdtlck, &rdtlck, DO_INDEX(ip));
+
+	sp->header.nextindex = nxt;
+
+	/*
+	 * finalize freelist of new right page
+	 */
+	fsi = rp->header.freelist;
+	f = &rp->slot[fsi];
+	for (fsi++; fsi < rp->header.maxslot; f++, fsi++)
+		f->next = fsi;
+	f->next = -1;
+
+	/*
+	 * Update directory index table for entries now in right page
+	 */
+	if ((rp->header.flag & BT_LEAF) && DO_INDEX(ip)) {
+		s64 lblock;
+
+		mp = NULL;
+		stbl = DT_GETSTBL(rp);
+		for (n = 0; n < rp->header.nextindex; n++) {
+			ldtentry = (struct ldtentry *) & rp->slot[stbl[n]];
+			modify_index(tid, ip, le32_to_cpu(ldtentry->index),
+				     rbn, n, &mp, &lblock);
+		}
+		if (mp)
+			release_metapage(mp);
+	}
+
+	/*
+	 * the skipped index was on the left page,
+	 */
+	if (skip <= off) {
+		/* insert the new entry in the split page */
+		dtInsertEntry(sp, skip, split->key, split->data, &sdtlck);
+
+		/* linelock stbl of split page */
+		if (sdtlck->index >= sdtlck->maxcnt)
+			sdtlck = (struct dt_lock *) txLinelock(sdtlck);
+		slv = & sdtlck->lv[sdtlck->index];
+		n = skip >> L2DTSLOTSIZE;
+		slv->offset = sp->header.stblindex + n;
+		slv->length =
+		    ((sp->header.nextindex - 1) >> L2DTSLOTSIZE) - n + 1;
+		sdtlck->index++;
+	}
+	/*
+	 * the skipped index was on the right page,
+	 */
+	else {
+		/* adjust the skip index to reflect the new position */
+		skip -= nxt;
+
+		/* insert the new entry in the right page */
+		dtInsertEntry(rp, skip, split->key, split->data, &rdtlck);
+	}
+
+      out:
+	*rmpp = rmp;
+	*rpxdp = *pxd;
+
+	return rc;
+}
+
+
+/*
+ *	dtExtendPage()
+ *
+ * function: extend 1st/only directory leaf page
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ *	   errno - failure;
+ *	return extended page pinned;
+ */
+static int dtExtendPage(tid_t tid,
+	     struct inode *ip, struct dtsplit * split, struct btstack * btstack)
+{
+	struct super_block *sb = ip->i_sb;
+	int rc;
+	struct metapage *smp, *pmp, *mp;
+	dtpage_t *sp, *pp;
+	struct pxdlist *pxdlist;
+	pxd_t *pxd, *tpxd;
+	int xlen, xsize;
+	int newstblindex, newstblsize;
+	int oldstblindex, oldstblsize;
+	int fsi, last;
+	struct dtslot *f;
+	struct btframe *parent;
+	int n;
+	struct dt_lock *dtlck;
+	s64 xaddr, txaddr;
+	struct tlock *tlck;
+	struct pxd_lock *pxdlock;
+	struct lv *lv;
+	uint type;
+	struct ldtentry *ldtentry;
+	u8 *stbl;
+
+	/* get page to extend */
+	smp = split->mp;
+	sp = DT_PAGE(ip, smp);
+
+	/* get parent/root page */
+	parent = BT_POP(btstack);
+	DT_GETPAGE(ip, parent->bn, pmp, PSIZE, pp, rc);
+	if (rc)
+		return (rc);
+
+	/*
+	 *	extend the extent
+	 */
+	pxdlist = split->pxdlist;
+	pxd = &pxdlist->pxd[pxdlist->npxd];
+	pxdlist->npxd++;
+
+	xaddr = addressPXD(pxd);
+	tpxd = &sp->header.self;
+	txaddr = addressPXD(tpxd);
+	/* in-place extension */
+	if (xaddr == txaddr) {
+		type = tlckEXTEND;
+	}
+	/* relocation */
+	else {
+		type = tlckNEW;
+
+		/* save moved extent descriptor for later free */
+		tlck = txMaplock(tid, ip, tlckDTREE | tlckRELOCATE);
+		pxdlock = (struct pxd_lock *) & tlck->lock;
+		pxdlock->flag = mlckFREEPXD;
+		pxdlock->pxd = sp->header.self;
+		pxdlock->index = 1;
+
+		/*
+		 * Update directory index table to reflect new page address
+		 */
+		if (DO_INDEX(ip)) {
+			s64 lblock;
+
+			mp = NULL;
+			stbl = DT_GETSTBL(sp);
+			for (n = 0; n < sp->header.nextindex; n++) {
+				ldtentry =
+				    (struct ldtentry *) & sp->slot[stbl[n]];
+				modify_index(tid, ip,
+					     le32_to_cpu(ldtentry->index),
+					     xaddr, n, &mp, &lblock);
+			}
+			if (mp)
+				release_metapage(mp);
+		}
+	}
+
+	/*
+	 *	extend the page
+	 */
+	sp->header.self = *pxd;
+
+	jfs_info("dtExtendPage: ip:0x%p smp:0x%p sp:0x%p", ip, smp, sp);
+
+	BT_MARK_DIRTY(smp, ip);
+	/*
+	 * acquire a transaction lock on the extended/leaf page
+	 */
+	tlck = txLock(tid, ip, smp, tlckDTREE | type);
+	dtlck = (struct dt_lock *) & tlck->lock;
+	lv = & dtlck->lv[0];
+
+	/* update buffer extent descriptor of extended page */
+	xlen = lengthPXD(pxd);
+	xsize = xlen << JFS_SBI(sb)->l2bsize;
+
+	/*
+	 * copy old stbl to new stbl at start of extended area
+	 */
+	oldstblindex = sp->header.stblindex;
+	oldstblsize = (sp->header.maxslot + 31) >> L2DTSLOTSIZE;
+	newstblindex = sp->header.maxslot;
+	n = xsize >> L2DTSLOTSIZE;
+	newstblsize = (n + 31) >> L2DTSLOTSIZE;
+	memcpy(&sp->slot[newstblindex], &sp->slot[oldstblindex],
+	       sp->header.nextindex);
+
+	/*
+	 * in-line extension: linelock old area of extended page
+	 */
+	if (type == tlckEXTEND) {
+		/* linelock header */
+		lv->offset = 0;
+		lv->length = 1;
+		dtlck->index++;
+		lv++;
+
+		/* linelock new stbl of extended page */
+		lv->offset = newstblindex;
+		lv->length = newstblsize;
+	}
+	/*
+	 * relocation: linelock whole relocated area
+	 */
+	else {
+		lv->offset = 0;
+		lv->length = sp->header.maxslot + newstblsize;
+	}
+
+	dtlck->index++;
+
+	sp->header.maxslot = n;
+	sp->header.stblindex = newstblindex;
+	/* sp->header.nextindex remains the same */
+
+	/*
+	 * add old stbl region at head of freelist
+	 */
+	fsi = oldstblindex;
+	f = &sp->slot[fsi];
+	last = sp->header.freelist;
+	for (n = 0; n < oldstblsize; n++, fsi++, f++) {
+		f->next = last;
+		last = fsi;
+	}
+	sp->header.freelist = last;
+	sp->header.freecnt += oldstblsize;
+
+	/*
+	 * append free region of newly extended area at tail of freelist
+	 */
+	/* init free region of newly extended area */
+	fsi = n = newstblindex + newstblsize;
+	f = &sp->slot[fsi];
+	for (fsi++; fsi < sp->header.maxslot; f++, fsi++)
+		f->next = fsi;
+	f->next = -1;
+
+	/* append new free region at tail of old freelist */
+	fsi = sp->header.freelist;
+	if (fsi == -1)
+		sp->header.freelist = n;
+	else {
+		do {
+			f = &sp->slot[fsi];
+			fsi = f->next;
+		} while (fsi != -1);
+
+		f->next = n;
+	}
+
+	sp->header.freecnt += sp->header.maxslot - n;
+
+	/*
+	 * insert the new entry
+	 */
+	dtInsertEntry(sp, split->index, split->key, split->data, &dtlck);
+
+	BT_MARK_DIRTY(pmp, ip);
+	/*
+	 * linelock any freeslots residing in old extent
+	 */
+	if (type == tlckEXTEND) {
+		n = sp->header.maxslot >> 2;
+		if (sp->header.freelist < n)
+			dtLinelockFreelist(sp, n, &dtlck);
+	}
+
+	/*
+	 *	update parent entry on the parent/root page
+	 */
+	/*
+	 * acquire a transaction lock on the parent/root page
+	 */
+	tlck = txLock(tid, ip, pmp, tlckDTREE | tlckENTRY);
+	dtlck = (struct dt_lock *) & tlck->lock;
+	lv = & dtlck->lv[dtlck->index];
+
+	/* linelock parent entry - 1st slot */
+	lv->offset = 1;
+	lv->length = 1;
+	dtlck->index++;
+
+	/* update the parent pxd for page extension */
+	tpxd = (pxd_t *) & pp->slot[1];
+	*tpxd = *pxd;
+
+	DT_PUTPAGE(pmp);
+	return 0;
+}
+
+
+/*
+ *	dtSplitRoot()
+ *
+ * function:
+ *	split the full root page into
+ *	original/root/split page and new right page
+ *	i.e., root remains fixed in tree anchor (inode) and
+ *	the root is copied to a single new right child page
+ *	since root page << non-root page, and
+ *	the split root page contains a single entry for the
+ *	new right child page.
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ *	   errno - failure;
+ *	return new page pinned;
+ */
+static int dtSplitRoot(tid_t tid,
+	    struct inode *ip, struct dtsplit * split, struct metapage ** rmpp)
+{
+	struct super_block *sb = ip->i_sb;
+	struct metapage *smp;
+	dtroot_t *sp;
+	struct metapage *rmp;
+	dtpage_t *rp;
+	s64 rbn;
+	int xlen;
+	int xsize;
+	struct dtslot *f;
+	s8 *stbl;
+	int fsi, stblsize, n;
+	struct idtentry *s;
+	pxd_t *ppxd;
+	struct pxdlist *pxdlist;
+	pxd_t *pxd;
+	struct dt_lock *dtlck;
+	struct tlock *tlck;
+	struct lv *lv;
+	int rc;
+
+	/* get split root page */
+	smp = split->mp;
+	sp = &JFS_IP(ip)->i_dtroot;
+
+	/*
+	 *	allocate/initialize a single (right) child page
+	 *
+	 * N.B. at first split, a one (or two) block to fit new entry
+	 * is allocated; at subsequent split, a full page is allocated;
+	 */
+	pxdlist = split->pxdlist;
+	pxd = &pxdlist->pxd[pxdlist->npxd];
+	pxdlist->npxd++;
+	rbn = addressPXD(pxd);
+	xlen = lengthPXD(pxd);
+	xsize = xlen << JFS_SBI(sb)->l2bsize;
+	rmp = get_metapage(ip, rbn, xsize, 1);
+	if (!rmp)
+		return -EIO;
+
+	rp = rmp->data;
+
+	/* Allocate blocks to quota. */
+	rc = dquot_alloc_block(ip, lengthPXD(pxd));
+	if (rc) {
+		release_metapage(rmp);
+		return rc;
+	}
+
+	BT_MARK_DIRTY(rmp, ip);
+	/*
+	 * acquire a transaction lock on the new right page
+	 */
+	tlck = txLock(tid, ip, rmp, tlckDTREE | tlckNEW);
+	dtlck = (struct dt_lock *) & tlck->lock;
+
+	rp->header.flag =
+	    (sp->header.flag & BT_LEAF) ? BT_LEAF : BT_INTERNAL;
+	rp->header.self = *pxd;
+
+	/* initialize sibling pointers */
+	rp->header.next = 0;
+	rp->header.prev = 0;
+
+	/*
+	 *	move in-line root page into new right page extent
+	 */
+	/* linelock header + copied entries + new stbl (1st slot) in new page */
+	ASSERT(dtlck->index == 0);
+	lv = & dtlck->lv[0];
+	lv->offset = 0;
+	lv->length = 10;	/* 1 + 8 + 1 */
+	dtlck->index++;
+
+	n = xsize >> L2DTSLOTSIZE;
+	rp->header.maxslot = n;
+	stblsize = (n + 31) >> L2DTSLOTSIZE;
+
+	/* copy old stbl to new stbl at start of extended area */
+	rp->header.stblindex = DTROOTMAXSLOT;
+	stbl = (s8 *) & rp->slot[DTROOTMAXSLOT];
+	memcpy(stbl, sp->header.stbl, sp->header.nextindex);
+	rp->header.nextindex = sp->header.nextindex;
+
+	/* copy old data area to start of new data area */
+	memcpy(&rp->slot[1], &sp->slot[1], IDATASIZE);
+
+	/*
+	 * append free region of newly extended area at tail of freelist
+	 */
+	/* init free region of newly extended area */
+	fsi = n = DTROOTMAXSLOT + stblsize;
+	f = &rp->slot[fsi];
+	for (fsi++; fsi < rp->header.maxslot; f++, fsi++)
+		f->next = fsi;
+	f->next = -1;
+
+	/* append new free region at tail of old freelist */
+	fsi = sp->header.freelist;
+	if (fsi == -1)
+		rp->header.freelist = n;
+	else {
+		rp->header.freelist = fsi;
+
+		do {
+			f = &rp->slot[fsi];
+			fsi = f->next;
+		} while (fsi != -1);
+
+		f->next = n;
+	}
+
+	rp->header.freecnt = sp->header.freecnt + rp->header.maxslot - n;
+
+	/*
+	 * Update directory index table for entries now in right page
+	 */
+	if ((rp->header.flag & BT_LEAF) && DO_INDEX(ip)) {
+		s64 lblock;
+		struct metapage *mp = NULL;
+		struct ldtentry *ldtentry;
+
+		stbl = DT_GETSTBL(rp);
+		for (n = 0; n < rp->header.nextindex; n++) {
+			ldtentry = (struct ldtentry *) & rp->slot[stbl[n]];
+			modify_index(tid, ip, le32_to_cpu(ldtentry->index),
+				     rbn, n, &mp, &lblock);
+		}
+		if (mp)
+			release_metapage(mp);
+	}
+	/*
+	 * insert the new entry into the new right/child page
+	 * (skip index in the new right page will not change)
+	 */
+	dtInsertEntry(rp, split->index, split->key, split->data, &dtlck);
+
+	/*
+	 *	reset parent/root page
+	 *
+	 * set the 1st entry offset to 0, which force the left-most key
+	 * at any level of the tree to be less than any search key.
+	 *
+	 * The btree comparison code guarantees that the left-most key on any
+	 * level of the tree is never used, so it doesn't need to be filled in.
+	 */
+	BT_MARK_DIRTY(smp, ip);
+	/*
+	 * acquire a transaction lock on the root page (in-memory inode)
+	 */
+	tlck = txLock(tid, ip, smp, tlckDTREE | tlckNEW | tlckBTROOT);
+	dtlck = (struct dt_lock *) & tlck->lock;
+
+	/* linelock root */
+	ASSERT(dtlck->index == 0);
+	lv = & dtlck->lv[0];
+	lv->offset = 0;
+	lv->length = DTROOTMAXSLOT;
+	dtlck->index++;
+
+	/* update page header of root */
+	if (sp->header.flag & BT_LEAF) {
+		sp->header.flag &= ~BT_LEAF;
+		sp->header.flag |= BT_INTERNAL;
+	}
+
+	/* init the first entry */
+	s = (struct idtentry *) & sp->slot[DTENTRYSTART];
+	ppxd = (pxd_t *) s;
+	*ppxd = *pxd;
+	s->next = -1;
+	s->namlen = 0;
+
+	stbl = sp->header.stbl;
+	stbl[0] = DTENTRYSTART;
+	sp->header.nextindex = 1;
+
+	/* init freelist */
+	fsi = DTENTRYSTART + 1;
+	f = &sp->slot[fsi];
+
+	/* init free region of remaining area */
+	for (fsi++; fsi < DTROOTMAXSLOT; f++, fsi++)
+		f->next = fsi;
+	f->next = -1;
+
+	sp->header.freelist = DTENTRYSTART + 1;
+	sp->header.freecnt = DTROOTMAXSLOT - (DTENTRYSTART + 1);
+
+	*rmpp = rmp;
+
+	return 0;
+}
+
+
+/*
+ *	dtDelete()
+ *
+ * function: delete the entry(s) referenced by a key.
+ *
+ * parameter:
+ *
+ * return:
+ */
+int dtDelete(tid_t tid,
+	 struct inode *ip, struct component_name * key, ino_t * ino, int flag)
+{
+	int rc = 0;
+	s64 bn;
+	struct metapage *mp, *imp;
+	dtpage_t *p;
+	int index;
+	struct btstack btstack;
+	struct dt_lock *dtlck;
+	struct tlock *tlck;
+	struct lv *lv;
+	int i;
+	struct ldtentry *ldtentry;
+	u8 *stbl;
+	u32 table_index, next_index;
+	struct metapage *nmp;
+	dtpage_t *np;
+
+	/*
+	 *	search for the entry to delete:
+	 *
+	 * dtSearch() returns (leaf page pinned, index at which to delete).
+	 */
+	if ((rc = dtSearch(ip, key, ino, &btstack, flag)))
+		return rc;
+
+	/* retrieve search result */
+	DT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+	/*
+	 * We need to find put the index of the next entry into the
+	 * directory index table in order to resume a readdir from this
+	 * entry.
+	 */
+	if (DO_INDEX(ip)) {
+		stbl = DT_GETSTBL(p);
+		ldtentry = (struct ldtentry *) & p->slot[stbl[index]];
+		table_index = le32_to_cpu(ldtentry->index);
+		if (index == (p->header.nextindex - 1)) {
+			/*
+			 * Last entry in this leaf page
+			 */
+			if ((p->header.flag & BT_ROOT)
+			    || (p->header.next == 0))
+				next_index = -1;
+			else {
+				/* Read next leaf page */
+				DT_GETPAGE(ip, le64_to_cpu(p->header.next),
+					   nmp, PSIZE, np, rc);
+				if (rc)
+					next_index = -1;
+				else {
+					stbl = DT_GETSTBL(np);
+					ldtentry =
+					    (struct ldtentry *) & np->
+					    slot[stbl[0]];
+					next_index =
+					    le32_to_cpu(ldtentry->index);
+					DT_PUTPAGE(nmp);
+				}
+			}
+		} else {
+			ldtentry =
+			    (struct ldtentry *) & p->slot[stbl[index + 1]];
+			next_index = le32_to_cpu(ldtentry->index);
+		}
+		free_index(tid, ip, table_index, next_index);
+	}
+	/*
+	 * the leaf page becomes empty, delete the page
+	 */
+	if (p->header.nextindex == 1) {
+		/* delete empty page */
+		rc = dtDeleteUp(tid, ip, mp, p, &btstack);
+	}
+	/*
+	 * the leaf page has other entries remaining:
+	 *
+	 * delete the entry from the leaf page.
+	 */
+	else {
+		BT_MARK_DIRTY(mp, ip);
+		/*
+		 * acquire a transaction lock on the leaf page
+		 */
+		tlck = txLock(tid, ip, mp, tlckDTREE | tlckENTRY);
+		dtlck = (struct dt_lock *) & tlck->lock;
+
+		/*
+		 * Do not assume that dtlck->index will be zero.  During a
+		 * rename within a directory, this transaction may have
+		 * modified this page already when adding the new entry.
+		 */
+
+		/* linelock header */
+		if (dtlck->index >= dtlck->maxcnt)
+			dtlck = (struct dt_lock *) txLinelock(dtlck);
+		lv = & dtlck->lv[dtlck->index];
+		lv->offset = 0;
+		lv->length = 1;
+		dtlck->index++;
+
+		/* linelock stbl of non-root leaf page */
+		if (!(p->header.flag & BT_ROOT)) {
+			if (dtlck->index >= dtlck->maxcnt)
+				dtlck = (struct dt_lock *) txLinelock(dtlck);
+			lv = & dtlck->lv[dtlck->index];
+			i = index >> L2DTSLOTSIZE;
+			lv->offset = p->header.stblindex + i;
+			lv->length =
+			    ((p->header.nextindex - 1) >> L2DTSLOTSIZE) -
+			    i + 1;
+			dtlck->index++;
+		}
+
+		/* free the leaf entry */
+		dtDeleteEntry(p, index, &dtlck);
+
+		/*
+		 * Update directory index table for entries moved in stbl
+		 */
+		if (DO_INDEX(ip) && index < p->header.nextindex) {
+			s64 lblock;
+
+			imp = NULL;
+			stbl = DT_GETSTBL(p);
+			for (i = index; i < p->header.nextindex; i++) {
+				ldtentry =
+				    (struct ldtentry *) & p->slot[stbl[i]];
+				modify_index(tid, ip,
+					     le32_to_cpu(ldtentry->index),
+					     bn, i, &imp, &lblock);
+			}
+			if (imp)
+				release_metapage(imp);
+		}
+
+		DT_PUTPAGE(mp);
+	}
+
+	return rc;
+}
+
+
+/*
+ *	dtDeleteUp()
+ *
+ * function:
+ *	free empty pages as propagating deletion up the tree
+ *
+ * parameter:
+ *
+ * return:
+ */
+static int dtDeleteUp(tid_t tid, struct inode *ip,
+	   struct metapage * fmp, dtpage_t * fp, struct btstack * btstack)
+{
+	int rc = 0;
+	struct metapage *mp;
+	dtpage_t *p;
+	int index, nextindex;
+	int xlen;
+	struct btframe *parent;
+	struct dt_lock *dtlck;
+	struct tlock *tlck;
+	struct lv *lv;
+	struct pxd_lock *pxdlock;
+	int i;
+
+	/*
+	 *	keep the root leaf page which has become empty
+	 */
+	if (BT_IS_ROOT(fmp)) {
+		/*
+		 * reset the root
+		 *
+		 * dtInitRoot() acquires txlock on the root
+		 */
+		dtInitRoot(tid, ip, PARENT(ip));
+
+		DT_PUTPAGE(fmp);
+
+		return 0;
+	}
+
+	/*
+	 *	free the non-root leaf page
+	 */
+	/*
+	 * acquire a transaction lock on the page
+	 *
+	 * write FREEXTENT|NOREDOPAGE log record
+	 * N.B. linelock is overlaid as freed extent descriptor, and
+	 * the buffer page is freed;
+	 */
+	tlck = txMaplock(tid, ip, tlckDTREE | tlckFREE);
+	pxdlock = (struct pxd_lock *) & tlck->lock;
+	pxdlock->flag = mlckFREEPXD;
+	pxdlock->pxd = fp->header.self;
+	pxdlock->index = 1;
+
+	/* update sibling pointers */
+	if ((rc = dtRelink(tid, ip, fp))) {
+		BT_PUTPAGE(fmp);
+		return rc;
+	}
+
+	xlen = lengthPXD(&fp->header.self);
+
+	/* Free quota allocation. */
+	dquot_free_block(ip, xlen);
+
+	/* free/invalidate its buffer page */
+	discard_metapage(fmp);
+
+	/*
+	 *	propagate page deletion up the directory tree
+	 *
+	 * If the delete from the parent page makes it empty,
+	 * continue all the way up the tree.
+	 * stop if the root page is reached (which is never deleted) or
+	 * if the entry deletion does not empty the page.
+	 */
+	while ((parent = BT_POP(btstack)) != NULL) {
+		/* pin the parent page <sp> */
+		DT_GETPAGE(ip, parent->bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		/*
+		 * free the extent of the child page deleted
+		 */
+		index = parent->index;
+
+		/*
+		 * delete the entry for the child page from parent
+		 */
+		nextindex = p->header.nextindex;
+
+		/*
+		 * the parent has the single entry being deleted:
+		 *
+		 * free the parent page which has become empty.
+		 */
+		if (nextindex == 1) {
+			/*
+			 * keep the root internal page which has become empty
+			 */
+			if (p->header.flag & BT_ROOT) {
+				/*
+				 * reset the root
+				 *
+				 * dtInitRoot() acquires txlock on the root
+				 */
+				dtInitRoot(tid, ip, PARENT(ip));
+
+				DT_PUTPAGE(mp);
+
+				return 0;
+			}
+			/*
+			 * free the parent page
+			 */
+			else {
+				/*
+				 * acquire a transaction lock on the page
+				 *
+				 * write FREEXTENT|NOREDOPAGE log record
+				 */
+				tlck =
+				    txMaplock(tid, ip,
+					      tlckDTREE | tlckFREE);
+				pxdlock = (struct pxd_lock *) & tlck->lock;
+				pxdlock->flag = mlckFREEPXD;
+				pxdlock->pxd = p->header.self;
+				pxdlock->index = 1;
+
+				/* update sibling pointers */
+				if ((rc = dtRelink(tid, ip, p))) {
+					DT_PUTPAGE(mp);
+					return rc;
+				}
+
+				xlen = lengthPXD(&p->header.self);
+
+				/* Free quota allocation */
+				dquot_free_block(ip, xlen);
+
+				/* free/invalidate its buffer page */
+				discard_metapage(mp);
+
+				/* propagate up */
+				continue;
+			}
+		}
+
+		/*
+		 * the parent has other entries remaining:
+		 *
+		 * delete the router entry from the parent page.
+		 */
+		BT_MARK_DIRTY(mp, ip);
+		/*
+		 * acquire a transaction lock on the page
+		 *
+		 * action: router entry deletion
+		 */
+		tlck = txLock(tid, ip, mp, tlckDTREE | tlckENTRY);
+		dtlck = (struct dt_lock *) & tlck->lock;
+
+		/* linelock header */
+		if (dtlck->index >= dtlck->maxcnt)
+			dtlck = (struct dt_lock *) txLinelock(dtlck);
+		lv = & dtlck->lv[dtlck->index];
+		lv->offset = 0;
+		lv->length = 1;
+		dtlck->index++;
+
+		/* linelock stbl of non-root leaf page */
+		if (!(p->header.flag & BT_ROOT)) {
+			if (dtlck->index < dtlck->maxcnt)
+				lv++;
+			else {
+				dtlck = (struct dt_lock *) txLinelock(dtlck);
+				lv = & dtlck->lv[0];
+			}
+			i = index >> L2DTSLOTSIZE;
+			lv->offset = p->header.stblindex + i;
+			lv->length =
+			    ((p->header.nextindex - 1) >> L2DTSLOTSIZE) -
+			    i + 1;
+			dtlck->index++;
+		}
+
+		/* free the router entry */
+		dtDeleteEntry(p, index, &dtlck);
+
+		/* reset key of new leftmost entry of level (for consistency) */
+		if (index == 0 &&
+		    ((p->header.flag & BT_ROOT) || p->header.prev == 0))
+			dtTruncateEntry(p, 0, &dtlck);
+
+		/* unpin the parent page */
+		DT_PUTPAGE(mp);
+
+		/* exit propagation up */
+		break;
+	}
+
+	if (!DO_INDEX(ip))
+		ip->i_size -= PSIZE;
+
+	return 0;
+}
+
+/*
+ *	dtRelink()
+ *
+ * function:
+ *	link around a freed page.
+ *
+ * parameter:
+ *	fp:	page to be freed
+ *
+ * return:
+ */
+static int dtRelink(tid_t tid, struct inode *ip, dtpage_t * p)
+{
+	int rc;
+	struct metapage *mp;
+	s64 nextbn, prevbn;
+	struct tlock *tlck;
+	struct dt_lock *dtlck;
+	struct lv *lv;
+
+	nextbn = le64_to_cpu(p->header.next);
+	prevbn = le64_to_cpu(p->header.prev);
+
+	/* update prev pointer of the next page */
+	if (nextbn != 0) {
+		DT_GETPAGE(ip, nextbn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		BT_MARK_DIRTY(mp, ip);
+		/*
+		 * acquire a transaction lock on the next page
+		 *
+		 * action: update prev pointer;
+		 */
+		tlck = txLock(tid, ip, mp, tlckDTREE | tlckRELINK);
+		jfs_info("dtRelink nextbn: tlck = 0x%p, ip = 0x%p, mp=0x%p",
+			tlck, ip, mp);
+		dtlck = (struct dt_lock *) & tlck->lock;
+
+		/* linelock header */
+		if (dtlck->index >= dtlck->maxcnt)
+			dtlck = (struct dt_lock *) txLinelock(dtlck);
+		lv = & dtlck->lv[dtlck->index];
+		lv->offset = 0;
+		lv->length = 1;
+		dtlck->index++;
+
+		p->header.prev = cpu_to_le64(prevbn);
+		DT_PUTPAGE(mp);
+	}
+
+	/* update next pointer of the previous page */
+	if (prevbn != 0) {
+		DT_GETPAGE(ip, prevbn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		BT_MARK_DIRTY(mp, ip);
+		/*
+		 * acquire a transaction lock on the prev page
+		 *
+		 * action: update next pointer;
+		 */
+		tlck = txLock(tid, ip, mp, tlckDTREE | tlckRELINK);
+		jfs_info("dtRelink prevbn: tlck = 0x%p, ip = 0x%p, mp=0x%p",
+			tlck, ip, mp);
+		dtlck = (struct dt_lock *) & tlck->lock;
+
+		/* linelock header */
+		if (dtlck->index >= dtlck->maxcnt)
+			dtlck = (struct dt_lock *) txLinelock(dtlck);
+		lv = & dtlck->lv[dtlck->index];
+		lv->offset = 0;
+		lv->length = 1;
+		dtlck->index++;
+
+		p->header.next = cpu_to_le64(nextbn);
+		DT_PUTPAGE(mp);
+	}
+
+	return 0;
+}
+
+
+/*
+ *	dtInitRoot()
+ *
+ * initialize directory root (inline in inode)
+ */
+void dtInitRoot(tid_t tid, struct inode *ip, u32 idotdot)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	dtroot_t *p;
+	int fsi;
+	struct dtslot *f;
+	struct tlock *tlck;
+	struct dt_lock *dtlck;
+	struct lv *lv;
+	u16 xflag_save;
+
+	/*
+	 * If this was previously an non-empty directory, we need to remove
+	 * the old directory table.
+	 */
+	if (DO_INDEX(ip)) {
+		if (!jfs_dirtable_inline(ip)) {
+			struct tblock *tblk = tid_to_tblock(tid);
+			/*
+			 * We're playing games with the tid's xflag.  If
+			 * we're removing a regular file, the file's xtree
+			 * is committed with COMMIT_PMAP, but we always
+			 * commit the directories xtree with COMMIT_PWMAP.
+			 */
+			xflag_save = tblk->xflag;
+			tblk->xflag = 0;
+			/*
+			 * xtTruncate isn't guaranteed to fully truncate
+			 * the xtree.  The caller needs to check i_size
+			 * after committing the transaction to see if
+			 * additional truncation is needed.  The
+			 * COMMIT_Stale flag tells caller that we
+			 * initiated the truncation.
+			 */
+			xtTruncate(tid, ip, 0, COMMIT_PWMAP);
+			set_cflag(COMMIT_Stale, ip);
+
+			tblk->xflag = xflag_save;
+		} else
+			ip->i_size = 1;
+
+		jfs_ip->next_index = 2;
+	} else
+		ip->i_size = IDATASIZE;
+
+	/*
+	 * acquire a transaction lock on the root
+	 *
+	 * action: directory initialization;
+	 */
+	tlck = txLock(tid, ip, (struct metapage *) & jfs_ip->bxflag,
+		      tlckDTREE | tlckENTRY | tlckBTROOT);
+	dtlck = (struct dt_lock *) & tlck->lock;
+
+	/* linelock root */
+	ASSERT(dtlck->index == 0);
+	lv = & dtlck->lv[0];
+	lv->offset = 0;
+	lv->length = DTROOTMAXSLOT;
+	dtlck->index++;
+
+	p = &jfs_ip->i_dtroot;
+
+	p->header.flag = DXD_INDEX | BT_ROOT | BT_LEAF;
+
+	p->header.nextindex = 0;
+
+	/* init freelist */
+	fsi = 1;
+	f = &p->slot[fsi];
+
+	/* init data area of root */
+	for (fsi++; fsi < DTROOTMAXSLOT; f++, fsi++)
+		f->next = fsi;
+	f->next = -1;
+
+	p->header.freelist = 1;
+	p->header.freecnt = 8;
+
+	/* init '..' entry */
+	p->header.idotdot = cpu_to_le32(idotdot);
+
+	return;
+}
+
+/*
+ *	add_missing_indices()
+ *
+ * function: Fix dtree page in which one or more entries has an invalid index.
+ *	     fsck.jfs should really fix this, but it currently does not.
+ *	     Called from jfs_readdir when bad index is detected.
+ */
+static void add_missing_indices(struct inode *inode, s64 bn)
+{
+	struct ldtentry *d;
+	struct dt_lock *dtlck;
+	int i;
+	uint index;
+	struct lv *lv;
+	struct metapage *mp;
+	dtpage_t *p;
+	int rc;
+	s8 *stbl;
+	tid_t tid;
+	struct tlock *tlck;
+
+	tid = txBegin(inode->i_sb, 0);
+
+	DT_GETPAGE(inode, bn, mp, PSIZE, p, rc);
+
+	if (rc) {
+		printk(KERN_ERR "DT_GETPAGE failed!\n");
+		goto end;
+	}
+	BT_MARK_DIRTY(mp, inode);
+
+	ASSERT(p->header.flag & BT_LEAF);
+
+	tlck = txLock(tid, inode, mp, tlckDTREE | tlckENTRY);
+	if (BT_IS_ROOT(mp))
+		tlck->type |= tlckBTROOT;
+
+	dtlck = (struct dt_lock *) &tlck->lock;
+
+	stbl = DT_GETSTBL(p);
+	for (i = 0; i < p->header.nextindex; i++) {
+		d = (struct ldtentry *) &p->slot[stbl[i]];
+		index = le32_to_cpu(d->index);
+		if ((index < 2) || (index >= JFS_IP(inode)->next_index)) {
+			d->index = cpu_to_le32(add_index(tid, inode, bn, i));
+			if (dtlck->index >= dtlck->maxcnt)
+				dtlck = (struct dt_lock *) txLinelock(dtlck);
+			lv = &dtlck->lv[dtlck->index];
+			lv->offset = stbl[i];
+			lv->length = 1;
+			dtlck->index++;
+		}
+	}
+
+	DT_PUTPAGE(mp);
+	(void) txCommit(tid, 1, &inode, 0);
+end:
+	txEnd(tid);
+}
+
+/*
+ * Buffer to hold directory entry info while traversing a dtree page
+ * before being fed to the filldir function
+ */
+struct jfs_dirent {
+	loff_t position;
+	int ino;
+	u16 name_len;
+	char name[];
+};
+
+/*
+ * function to determine next variable-sized jfs_dirent in buffer
+ */
+static inline struct jfs_dirent *next_jfs_dirent(struct jfs_dirent *dirent)
+{
+	return (struct jfs_dirent *)
+		((char *)dirent +
+		 ((sizeof (struct jfs_dirent) + dirent->name_len + 1 +
+		   sizeof (loff_t) - 1) &
+		  ~(sizeof (loff_t) - 1)));
+}
+
+/*
+ *	jfs_readdir()
+ *
+ * function: read directory entries sequentially
+ *	from the specified entry offset
+ *
+ * parameter:
+ *
+ * return: offset = (pn, index) of start entry
+ *	of next jfs_readdir()/dtRead()
+ */
+int jfs_readdir(struct file *file, struct dir_context *ctx)
+{
+	struct inode *ip = file_inode(file);
+	struct nls_table *codepage = JFS_SBI(ip->i_sb)->nls_tab;
+	int rc = 0;
+	loff_t dtpos;	/* legacy OS/2 style position */
+	struct dtoffset {
+		s16 pn;
+		s16 index;
+		s32 unused;
+	} *dtoffset = (struct dtoffset *) &dtpos;
+	s64 bn;
+	struct metapage *mp;
+	dtpage_t *p;
+	int index;
+	s8 *stbl;
+	struct btstack btstack;
+	int i, next;
+	struct ldtentry *d;
+	struct dtslot *t;
+	int d_namleft, len, outlen;
+	unsigned long dirent_buf;
+	char *name_ptr;
+	u32 dir_index;
+	int do_index = 0;
+	uint loop_count = 0;
+	struct jfs_dirent *jfs_dirent;
+	int jfs_dirents;
+	int overflow, fix_page, page_fixed = 0;
+	static int unique_pos = 2;	/* If we can't fix broken index */
+
+	if (ctx->pos == DIREND)
+		return 0;
+
+	if (DO_INDEX(ip)) {
+		/*
+		 * persistent index is stored in directory entries.
+		 * Special cases:	 0 = .
+		 *			 1 = ..
+		 *			-1 = End of directory
+		 */
+		do_index = 1;
+
+		dir_index = (u32) ctx->pos;
+
+		/*
+		 * NFSv4 reserves cookies 1 and 2 for . and .. so the value
+		 * we return to the vfs is one greater than the one we use
+		 * internally.
+		 */
+		if (dir_index)
+			dir_index--;
+
+		if (dir_index > 1) {
+			struct dir_table_slot dirtab_slot;
+
+			if (dtEmpty(ip) ||
+			    (dir_index >= JFS_IP(ip)->next_index)) {
+				/* Stale position.  Directory has shrunk */
+				ctx->pos = DIREND;
+				return 0;
+			}
+		      repeat:
+			rc = read_index(ip, dir_index, &dirtab_slot);
+			if (rc) {
+				ctx->pos = DIREND;
+				return rc;
+			}
+			if (dirtab_slot.flag == DIR_INDEX_FREE) {
+				if (loop_count++ > JFS_IP(ip)->next_index) {
+					jfs_err("jfs_readdir detected infinite loop!");
+					ctx->pos = DIREND;
+					return 0;
+				}
+				dir_index = le32_to_cpu(dirtab_slot.addr2);
+				if (dir_index == -1) {
+					ctx->pos = DIREND;
+					return 0;
+				}
+				goto repeat;
+			}
+			bn = addressDTS(&dirtab_slot);
+			index = dirtab_slot.slot;
+			DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+			if (rc) {
+				ctx->pos = DIREND;
+				return 0;
+			}
+			if (p->header.flag & BT_INTERNAL) {
+				jfs_err("jfs_readdir: bad index table");
+				DT_PUTPAGE(mp);
+				ctx->pos = DIREND;
+				return 0;
+			}
+		} else {
+			if (dir_index == 0) {
+				/*
+				 * self "."
+				 */
+				ctx->pos = 1;
+				if (!dir_emit(ctx, ".", 1, ip->i_ino, DT_DIR))
+					return 0;
+			}
+			/*
+			 * parent ".."
+			 */
+			ctx->pos = 2;
+			if (!dir_emit(ctx, "..", 2, PARENT(ip), DT_DIR))
+				return 0;
+
+			/*
+			 * Find first entry of left-most leaf
+			 */
+			if (dtEmpty(ip)) {
+				ctx->pos = DIREND;
+				return 0;
+			}
+
+			if ((rc = dtReadFirst(ip, &btstack)))
+				return rc;
+
+			DT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+		}
+	} else {
+		/*
+		 * Legacy filesystem - OS/2 & Linux JFS < 0.3.6
+		 *
+		 * pn = 0; index = 1:	First entry "."
+		 * pn = 0; index = 2:	Second entry ".."
+		 * pn > 0:		Real entries, pn=1 -> leftmost page
+		 * pn = index = -1:	No more entries
+		 */
+		dtpos = ctx->pos;
+		if (dtpos < 2) {
+			/* build "." entry */
+			ctx->pos = 1;
+			if (!dir_emit(ctx, ".", 1, ip->i_ino, DT_DIR))
+				return 0;
+			dtoffset->index = 2;
+			ctx->pos = dtpos;
+		}
+
+		if (dtoffset->pn == 0) {
+			if (dtoffset->index == 2) {
+				/* build ".." entry */
+				if (!dir_emit(ctx, "..", 2, PARENT(ip), DT_DIR))
+					return 0;
+			} else {
+				jfs_err("jfs_readdir called with invalid offset!");
+			}
+			dtoffset->pn = 1;
+			dtoffset->index = 0;
+			ctx->pos = dtpos;
+		}
+
+		if (dtEmpty(ip)) {
+			ctx->pos = DIREND;
+			return 0;
+		}
+
+		if ((rc = dtReadNext(ip, &ctx->pos, &btstack))) {
+			jfs_err("jfs_readdir: unexpected rc = %d from dtReadNext",
+				rc);
+			ctx->pos = DIREND;
+			return 0;
+		}
+		/* get start leaf page and index */
+		DT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+		/* offset beyond directory eof ? */
+		if (bn < 0) {
+			ctx->pos = DIREND;
+			return 0;
+		}
+	}
+
+	dirent_buf = __get_free_page(GFP_KERNEL);
+	if (dirent_buf == 0) {
+		DT_PUTPAGE(mp);
+		jfs_warn("jfs_readdir: __get_free_page failed!");
+		ctx->pos = DIREND;
+		return -ENOMEM;
+	}
+
+	while (1) {
+		jfs_dirent = (struct jfs_dirent *) dirent_buf;
+		jfs_dirents = 0;
+		overflow = fix_page = 0;
+
+		stbl = DT_GETSTBL(p);
+
+		for (i = index; i < p->header.nextindex; i++) {
+			d = (struct ldtentry *) & p->slot[stbl[i]];
+
+			if (((long) jfs_dirent + d->namlen + 1) >
+			    (dirent_buf + PAGE_SIZE)) {
+				/* DBCS codepages could overrun dirent_buf */
+				index = i;
+				overflow = 1;
+				break;
+			}
+
+			d_namleft = d->namlen;
+			name_ptr = jfs_dirent->name;
+			jfs_dirent->ino = le32_to_cpu(d->inumber);
+
+			if (do_index) {
+				len = min(d_namleft, DTLHDRDATALEN);
+				jfs_dirent->position = le32_to_cpu(d->index);
+				/*
+				 * d->index should always be valid, but it
+				 * isn't.  fsck.jfs doesn't create the
+				 * directory index for the lost+found
+				 * directory.  Rather than let it go,
+				 * we can try to fix it.
+				 */
+				if ((jfs_dirent->position < 2) ||
+				    (jfs_dirent->position >=
+				     JFS_IP(ip)->next_index)) {
+					if (!page_fixed && !isReadOnly(ip)) {
+						fix_page = 1;
+						/*
+						 * setting overflow and setting
+						 * index to i will cause the
+						 * same page to be processed
+						 * again starting here
+						 */
+						overflow = 1;
+						index = i;
+						break;
+					}
+					jfs_dirent->position = unique_pos++;
+				}
+				/*
+				 * We add 1 to the index because we may
+				 * use a value of 2 internally, and NFSv4
+				 * doesn't like that.
+				 */
+				jfs_dirent->position++;
+			} else {
+				jfs_dirent->position = dtpos;
+				len = min(d_namleft, DTLHDRDATALEN_LEGACY);
+			}
+
+			/* copy the name of head/only segment */
+			outlen = jfs_strfromUCS_le(name_ptr, d->name, len,
+						   codepage);
+			jfs_dirent->name_len = outlen;
+
+			/* copy name in the additional segment(s) */
+			next = d->next;
+			while (next >= 0) {
+				t = (struct dtslot *) & p->slot[next];
+				name_ptr += outlen;
+				d_namleft -= len;
+				/* Sanity Check */
+				if (d_namleft == 0) {
+					jfs_error(ip->i_sb,
+						  "JFS:Dtree error: ino = %ld, bn=%lld, index = %d\n",
+						  (long)ip->i_ino,
+						  (long long)bn,
+						  i);
+					goto skip_one;
+				}
+				len = min(d_namleft, DTSLOTDATALEN);
+				outlen = jfs_strfromUCS_le(name_ptr, t->name,
+							   len, codepage);
+				jfs_dirent->name_len += outlen;
+
+				next = t->next;
+			}
+
+			jfs_dirents++;
+			jfs_dirent = next_jfs_dirent(jfs_dirent);
+skip_one:
+			if (!do_index)
+				dtoffset->index++;
+		}
+
+		if (!overflow) {
+			/* Point to next leaf page */
+			if (p->header.flag & BT_ROOT)
+				bn = 0;
+			else {
+				bn = le64_to_cpu(p->header.next);
+				index = 0;
+				/* update offset (pn:index) for new page */
+				if (!do_index) {
+					dtoffset->pn++;
+					dtoffset->index = 0;
+				}
+			}
+			page_fixed = 0;
+		}
+
+		/* unpin previous leaf page */
+		DT_PUTPAGE(mp);
+
+		jfs_dirent = (struct jfs_dirent *) dirent_buf;
+		while (jfs_dirents--) {
+			ctx->pos = jfs_dirent->position;
+			if (!dir_emit(ctx, jfs_dirent->name,
+				    jfs_dirent->name_len,
+				    jfs_dirent->ino, DT_UNKNOWN))
+				goto out;
+			jfs_dirent = next_jfs_dirent(jfs_dirent);
+		}
+
+		if (fix_page) {
+			add_missing_indices(ip, bn);
+			page_fixed = 1;
+		}
+
+		if (!overflow && (bn == 0)) {
+			ctx->pos = DIREND;
+			break;
+		}
+
+		DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc) {
+			free_page(dirent_buf);
+			return rc;
+		}
+	}
+
+      out:
+	free_page(dirent_buf);
+
+	return rc;
+}
+
+
+/*
+ *	dtReadFirst()
+ *
+ * function: get the leftmost page of the directory
+ */
+static int dtReadFirst(struct inode *ip, struct btstack * btstack)
+{
+	int rc = 0;
+	s64 bn;
+	int psize = 288;	/* initial in-line directory */
+	struct metapage *mp;
+	dtpage_t *p;
+	s8 *stbl;
+	struct btframe *btsp;
+	pxd_t *xd;
+
+	BT_CLR(btstack);	/* reset stack */
+
+	/*
+	 *	descend leftmost path of the tree
+	 *
+	 * by convention, root bn = 0.
+	 */
+	for (bn = 0;;) {
+		DT_GETPAGE(ip, bn, mp, psize, p, rc);
+		if (rc)
+			return rc;
+
+		/*
+		 * leftmost leaf page
+		 */
+		if (p->header.flag & BT_LEAF) {
+			/* return leftmost entry */
+			btsp = btstack->top;
+			btsp->bn = bn;
+			btsp->index = 0;
+			btsp->mp = mp;
+
+			return 0;
+		}
+
+		/*
+		 * descend down to leftmost child page
+		 */
+		if (BT_STACK_FULL(btstack)) {
+			DT_PUTPAGE(mp);
+			jfs_error(ip->i_sb, "btstack overrun\n");
+			BT_STACK_DUMP(btstack);
+			return -EIO;
+		}
+		/* push (bn, index) of the parent page/entry */
+		BT_PUSH(btstack, bn, 0);
+
+		/* get the leftmost entry */
+		stbl = DT_GETSTBL(p);
+		xd = (pxd_t *) & p->slot[stbl[0]];
+
+		/* get the child page block address */
+		bn = addressPXD(xd);
+		psize = lengthPXD(xd) << JFS_SBI(ip->i_sb)->l2bsize;
+
+		/* unpin the parent page */
+		DT_PUTPAGE(mp);
+	}
+}
+
+
+/*
+ *	dtReadNext()
+ *
+ * function: get the page of the specified offset (pn:index)
+ *
+ * return: if (offset > eof), bn = -1;
+ *
+ * note: if index > nextindex of the target leaf page,
+ * start with 1st entry of next leaf page;
+ */
+static int dtReadNext(struct inode *ip, loff_t * offset,
+		      struct btstack * btstack)
+{
+	int rc = 0;
+	struct dtoffset {
+		s16 pn;
+		s16 index;
+		s32 unused;
+	} *dtoffset = (struct dtoffset *) offset;
+	s64 bn;
+	struct metapage *mp;
+	dtpage_t *p;
+	int index;
+	int pn;
+	s8 *stbl;
+	struct btframe *btsp, *parent;
+	pxd_t *xd;
+
+	/*
+	 * get leftmost leaf page pinned
+	 */
+	if ((rc = dtReadFirst(ip, btstack)))
+		return rc;
+
+	/* get leaf page */
+	DT_GETSEARCH(ip, btstack->top, bn, mp, p, index);
+
+	/* get the start offset (pn:index) */
+	pn = dtoffset->pn - 1;	/* Now pn = 0 represents leftmost leaf */
+	index = dtoffset->index;
+
+	/* start at leftmost page ? */
+	if (pn == 0) {
+		/* offset beyond eof ? */
+		if (index < p->header.nextindex)
+			goto out;
+
+		if (p->header.flag & BT_ROOT) {
+			bn = -1;
+			goto out;
+		}
+
+		/* start with 1st entry of next leaf page */
+		dtoffset->pn++;
+		dtoffset->index = index = 0;
+		goto a;
+	}
+
+	/* start at non-leftmost page: scan parent pages for large pn */
+	if (p->header.flag & BT_ROOT) {
+		bn = -1;
+		goto out;
+	}
+
+	/* start after next leaf page ? */
+	if (pn > 1)
+		goto b;
+
+	/* get leaf page pn = 1 */
+      a:
+	bn = le64_to_cpu(p->header.next);
+
+	/* unpin leaf page */
+	DT_PUTPAGE(mp);
+
+	/* offset beyond eof ? */
+	if (bn == 0) {
+		bn = -1;
+		goto out;
+	}
+
+	goto c;
+
+	/*
+	 * scan last internal page level to get target leaf page
+	 */
+      b:
+	/* unpin leftmost leaf page */
+	DT_PUTPAGE(mp);
+
+	/* get left most parent page */
+	btsp = btstack->top;
+	parent = btsp - 1;
+	bn = parent->bn;
+	DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+	if (rc)
+		return rc;
+
+	/* scan parent pages at last internal page level */
+	while (pn >= p->header.nextindex) {
+		pn -= p->header.nextindex;
+
+		/* get next parent page address */
+		bn = le64_to_cpu(p->header.next);
+
+		/* unpin current parent page */
+		DT_PUTPAGE(mp);
+
+		/* offset beyond eof ? */
+		if (bn == 0) {
+			bn = -1;
+			goto out;
+		}
+
+		/* get next parent page */
+		DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		/* update parent page stack frame */
+		parent->bn = bn;
+	}
+
+	/* get leaf page address */
+	stbl = DT_GETSTBL(p);
+	xd = (pxd_t *) & p->slot[stbl[pn]];
+	bn = addressPXD(xd);
+
+	/* unpin parent page */
+	DT_PUTPAGE(mp);
+
+	/*
+	 * get target leaf page
+	 */
+      c:
+	DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+	if (rc)
+		return rc;
+
+	/*
+	 * leaf page has been completed:
+	 * start with 1st entry of next leaf page
+	 */
+	if (index >= p->header.nextindex) {
+		bn = le64_to_cpu(p->header.next);
+
+		/* unpin leaf page */
+		DT_PUTPAGE(mp);
+
+		/* offset beyond eof ? */
+		if (bn == 0) {
+			bn = -1;
+			goto out;
+		}
+
+		/* get next leaf page */
+		DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		/* start with 1st entry of next leaf page */
+		dtoffset->pn++;
+		dtoffset->index = 0;
+	}
+
+      out:
+	/* return target leaf page pinned */
+	btsp = btstack->top;
+	btsp->bn = bn;
+	btsp->index = dtoffset->index;
+	btsp->mp = mp;
+
+	return 0;
+}
+
+
+/*
+ *	dtCompare()
+ *
+ * function: compare search key with an internal entry
+ *
+ * return:
+ *	< 0 if k is < record
+ *	= 0 if k is = record
+ *	> 0 if k is > record
+ */
+static int dtCompare(struct component_name * key,	/* search key */
+		     dtpage_t * p,	/* directory page */
+		     int si)
+{				/* entry slot index */
+	wchar_t *kname;
+	__le16 *name;
+	int klen, namlen, len, rc;
+	struct idtentry *ih;
+	struct dtslot *t;
+
+	/*
+	 * force the left-most key on internal pages, at any level of
+	 * the tree, to be less than any search key.
+	 * this obviates having to update the leftmost key on an internal
+	 * page when the user inserts a new key in the tree smaller than
+	 * anything that has been stored.
+	 *
+	 * (? if/when dtSearch() narrows down to 1st entry (index = 0),
+	 * at any internal page at any level of the tree,
+	 * it descends to child of the entry anyway -
+	 * ? make the entry as min size dummy entry)
+	 *
+	 * if (e->index == 0 && h->prevpg == P_INVALID && !(h->flags & BT_LEAF))
+	 * return (1);
+	 */
+
+	kname = key->name;
+	klen = key->namlen;
+
+	ih = (struct idtentry *) & p->slot[si];
+	si = ih->next;
+	name = ih->name;
+	namlen = ih->namlen;
+	len = min(namlen, DTIHDRDATALEN);
+
+	/* compare with head/only segment */
+	len = min(klen, len);
+	if ((rc = UniStrncmp_le(kname, name, len)))
+		return rc;
+
+	klen -= len;
+	namlen -= len;
+
+	/* compare with additional segment(s) */
+	kname += len;
+	while (klen > 0 && namlen > 0) {
+		/* compare with next name segment */
+		t = (struct dtslot *) & p->slot[si];
+		len = min(namlen, DTSLOTDATALEN);
+		len = min(klen, len);
+		name = t->name;
+		if ((rc = UniStrncmp_le(kname, name, len)))
+			return rc;
+
+		klen -= len;
+		namlen -= len;
+		kname += len;
+		si = t->next;
+	}
+
+	return (klen - namlen);
+}
+
+
+
+
+/*
+ *	ciCompare()
+ *
+ * function: compare search key with an (leaf/internal) entry
+ *
+ * return:
+ *	< 0 if k is < record
+ *	= 0 if k is = record
+ *	> 0 if k is > record
+ */
+static int ciCompare(struct component_name * key,	/* search key */
+		     dtpage_t * p,	/* directory page */
+		     int si,	/* entry slot index */
+		     int flag)
+{
+	wchar_t *kname, x;
+	__le16 *name;
+	int klen, namlen, len, rc;
+	struct ldtentry *lh;
+	struct idtentry *ih;
+	struct dtslot *t;
+	int i;
+
+	/*
+	 * force the left-most key on internal pages, at any level of
+	 * the tree, to be less than any search key.
+	 * this obviates having to update the leftmost key on an internal
+	 * page when the user inserts a new key in the tree smaller than
+	 * anything that has been stored.
+	 *
+	 * (? if/when dtSearch() narrows down to 1st entry (index = 0),
+	 * at any internal page at any level of the tree,
+	 * it descends to child of the entry anyway -
+	 * ? make the entry as min size dummy entry)
+	 *
+	 * if (e->index == 0 && h->prevpg == P_INVALID && !(h->flags & BT_LEAF))
+	 * return (1);
+	 */
+
+	kname = key->name;
+	klen = key->namlen;
+
+	/*
+	 * leaf page entry
+	 */
+	if (p->header.flag & BT_LEAF) {
+		lh = (struct ldtentry *) & p->slot[si];
+		si = lh->next;
+		name = lh->name;
+		namlen = lh->namlen;
+		if (flag & JFS_DIR_INDEX)
+			len = min(namlen, DTLHDRDATALEN);
+		else
+			len = min(namlen, DTLHDRDATALEN_LEGACY);
+	}
+	/*
+	 * internal page entry
+	 */
+	else {
+		ih = (struct idtentry *) & p->slot[si];
+		si = ih->next;
+		name = ih->name;
+		namlen = ih->namlen;
+		len = min(namlen, DTIHDRDATALEN);
+	}
+
+	/* compare with head/only segment */
+	len = min(klen, len);
+	for (i = 0; i < len; i++, kname++, name++) {
+		/* only uppercase if case-insensitive support is on */
+		if ((flag & JFS_OS2) == JFS_OS2)
+			x = UniToupper(le16_to_cpu(*name));
+		else
+			x = le16_to_cpu(*name);
+		if ((rc = *kname - x))
+			return rc;
+	}
+
+	klen -= len;
+	namlen -= len;
+
+	/* compare with additional segment(s) */
+	while (klen > 0 && namlen > 0) {
+		/* compare with next name segment */
+		t = (struct dtslot *) & p->slot[si];
+		len = min(namlen, DTSLOTDATALEN);
+		len = min(klen, len);
+		name = t->name;
+		for (i = 0; i < len; i++, kname++, name++) {
+			/* only uppercase if case-insensitive support is on */
+			if ((flag & JFS_OS2) == JFS_OS2)
+				x = UniToupper(le16_to_cpu(*name));
+			else
+				x = le16_to_cpu(*name);
+
+			if ((rc = *kname - x))
+				return rc;
+		}
+
+		klen -= len;
+		namlen -= len;
+		si = t->next;
+	}
+
+	return (klen - namlen);
+}
+
+
+/*
+ *	ciGetLeafPrefixKey()
+ *
+ * function: compute prefix of suffix compression
+ *	     from two adjacent leaf entries
+ *	     across page boundary
+ *
+ * return: non-zero on error
+ *
+ */
+static int ciGetLeafPrefixKey(dtpage_t * lp, int li, dtpage_t * rp,
+			       int ri, struct component_name * key, int flag)
+{
+	int klen, namlen;
+	wchar_t *pl, *pr, *kname;
+	struct component_name lkey;
+	struct component_name rkey;
+
+	lkey.name = kmalloc_array(JFS_NAME_MAX + 1, sizeof(wchar_t),
+					GFP_KERNEL);
+	if (lkey.name == NULL)
+		return -ENOMEM;
+
+	rkey.name = kmalloc_array(JFS_NAME_MAX + 1, sizeof(wchar_t),
+					GFP_KERNEL);
+	if (rkey.name == NULL) {
+		kfree(lkey.name);
+		return -ENOMEM;
+	}
+
+	/* get left and right key */
+	dtGetKey(lp, li, &lkey, flag);
+	lkey.name[lkey.namlen] = 0;
+
+	if ((flag & JFS_OS2) == JFS_OS2)
+		ciToUpper(&lkey);
+
+	dtGetKey(rp, ri, &rkey, flag);
+	rkey.name[rkey.namlen] = 0;
+
+
+	if ((flag & JFS_OS2) == JFS_OS2)
+		ciToUpper(&rkey);
+
+	/* compute prefix */
+	klen = 0;
+	kname = key->name;
+	namlen = min(lkey.namlen, rkey.namlen);
+	for (pl = lkey.name, pr = rkey.name;
+	     namlen; pl++, pr++, namlen--, klen++, kname++) {
+		*kname = *pr;
+		if (*pl != *pr) {
+			key->namlen = klen + 1;
+			goto free_names;
+		}
+	}
+
+	/* l->namlen <= r->namlen since l <= r */
+	if (lkey.namlen < rkey.namlen) {
+		*kname = *pr;
+		key->namlen = klen + 1;
+	} else			/* l->namelen == r->namelen */
+		key->namlen = klen;
+
+free_names:
+	kfree(lkey.name);
+	kfree(rkey.name);
+	return 0;
+}
+
+
+
+/*
+ *	dtGetKey()
+ *
+ * function: get key of the entry
+ */
+static void dtGetKey(dtpage_t * p, int i,	/* entry index */
+		     struct component_name * key, int flag)
+{
+	int si;
+	s8 *stbl;
+	struct ldtentry *lh;
+	struct idtentry *ih;
+	struct dtslot *t;
+	int namlen, len;
+	wchar_t *kname;
+	__le16 *name;
+
+	/* get entry */
+	stbl = DT_GETSTBL(p);
+	si = stbl[i];
+	if (p->header.flag & BT_LEAF) {
+		lh = (struct ldtentry *) & p->slot[si];
+		si = lh->next;
+		namlen = lh->namlen;
+		name = lh->name;
+		if (flag & JFS_DIR_INDEX)
+			len = min(namlen, DTLHDRDATALEN);
+		else
+			len = min(namlen, DTLHDRDATALEN_LEGACY);
+	} else {
+		ih = (struct idtentry *) & p->slot[si];
+		si = ih->next;
+		namlen = ih->namlen;
+		name = ih->name;
+		len = min(namlen, DTIHDRDATALEN);
+	}
+
+	key->namlen = namlen;
+	kname = key->name;
+
+	/*
+	 * move head/only segment
+	 */
+	UniStrncpy_from_le(kname, name, len);
+
+	/*
+	 * move additional segment(s)
+	 */
+	while (si >= 0) {
+		/* get next segment */
+		t = &p->slot[si];
+		kname += len;
+		namlen -= len;
+		len = min(namlen, DTSLOTDATALEN);
+		UniStrncpy_from_le(kname, t->name, len);
+
+		si = t->next;
+	}
+}
+
+
+/*
+ *	dtInsertEntry()
+ *
+ * function: allocate free slot(s) and
+ *	     write a leaf/internal entry
+ *
+ * return: entry slot index
+ */
+static void dtInsertEntry(dtpage_t * p, int index, struct component_name * key,
+			  ddata_t * data, struct dt_lock ** dtlock)
+{
+	struct dtslot *h, *t;
+	struct ldtentry *lh = NULL;
+	struct idtentry *ih = NULL;
+	int hsi, fsi, klen, len, nextindex;
+	wchar_t *kname;
+	__le16 *name;
+	s8 *stbl;
+	pxd_t *xd;
+	struct dt_lock *dtlck = *dtlock;
+	struct lv *lv;
+	int xsi, n;
+	s64 bn = 0;
+	struct metapage *mp = NULL;
+
+	klen = key->namlen;
+	kname = key->name;
+
+	/* allocate a free slot */
+	hsi = fsi = p->header.freelist;
+	h = &p->slot[fsi];
+	p->header.freelist = h->next;
+	--p->header.freecnt;
+
+	/* open new linelock */
+	if (dtlck->index >= dtlck->maxcnt)
+		dtlck = (struct dt_lock *) txLinelock(dtlck);
+
+	lv = & dtlck->lv[dtlck->index];
+	lv->offset = hsi;
+
+	/* write head/only segment */
+	if (p->header.flag & BT_LEAF) {
+		lh = (struct ldtentry *) h;
+		lh->next = h->next;
+		lh->inumber = cpu_to_le32(data->leaf.ino);
+		lh->namlen = klen;
+		name = lh->name;
+		if (data->leaf.ip) {
+			len = min(klen, DTLHDRDATALEN);
+			if (!(p->header.flag & BT_ROOT))
+				bn = addressPXD(&p->header.self);
+			lh->index = cpu_to_le32(add_index(data->leaf.tid,
+							  data->leaf.ip,
+							  bn, index));
+		} else
+			len = min(klen, DTLHDRDATALEN_LEGACY);
+	} else {
+		ih = (struct idtentry *) h;
+		ih->next = h->next;
+		xd = (pxd_t *) ih;
+		*xd = data->xd;
+		ih->namlen = klen;
+		name = ih->name;
+		len = min(klen, DTIHDRDATALEN);
+	}
+
+	UniStrncpy_to_le(name, kname, len);
+
+	n = 1;
+	xsi = hsi;
+
+	/* write additional segment(s) */
+	t = h;
+	klen -= len;
+	while (klen) {
+		/* get free slot */
+		fsi = p->header.freelist;
+		t = &p->slot[fsi];
+		p->header.freelist = t->next;
+		--p->header.freecnt;
+
+		/* is next slot contiguous ? */
+		if (fsi != xsi + 1) {
+			/* close current linelock */
+			lv->length = n;
+			dtlck->index++;
+
+			/* open new linelock */
+			if (dtlck->index < dtlck->maxcnt)
+				lv++;
+			else {
+				dtlck = (struct dt_lock *) txLinelock(dtlck);
+				lv = & dtlck->lv[0];
+			}
+
+			lv->offset = fsi;
+			n = 0;
+		}
+
+		kname += len;
+		len = min(klen, DTSLOTDATALEN);
+		UniStrncpy_to_le(t->name, kname, len);
+
+		n++;
+		xsi = fsi;
+		klen -= len;
+	}
+
+	/* close current linelock */
+	lv->length = n;
+	dtlck->index++;
+
+	*dtlock = dtlck;
+
+	/* terminate last/only segment */
+	if (h == t) {
+		/* single segment entry */
+		if (p->header.flag & BT_LEAF)
+			lh->next = -1;
+		else
+			ih->next = -1;
+	} else
+		/* multi-segment entry */
+		t->next = -1;
+
+	/* if insert into middle, shift right succeeding entries in stbl */
+	stbl = DT_GETSTBL(p);
+	nextindex = p->header.nextindex;
+	if (index < nextindex) {
+		memmove(stbl + index + 1, stbl + index, nextindex - index);
+
+		if ((p->header.flag & BT_LEAF) && data->leaf.ip) {
+			s64 lblock;
+
+			/*
+			 * Need to update slot number for entries that moved
+			 * in the stbl
+			 */
+			mp = NULL;
+			for (n = index + 1; n <= nextindex; n++) {
+				lh = (struct ldtentry *) & (p->slot[stbl[n]]);
+				modify_index(data->leaf.tid, data->leaf.ip,
+					     le32_to_cpu(lh->index), bn, n,
+					     &mp, &lblock);
+			}
+			if (mp)
+				release_metapage(mp);
+		}
+	}
+
+	stbl[index] = hsi;
+
+	/* advance next available entry index of stbl */
+	++p->header.nextindex;
+}
+
+
+/*
+ *	dtMoveEntry()
+ *
+ * function: move entries from split/left page to new/right page
+ *
+ *	nextindex of dst page and freelist/freecnt of both pages
+ *	are updated.
+ */
+static void dtMoveEntry(dtpage_t * sp, int si, dtpage_t * dp,
+			struct dt_lock ** sdtlock, struct dt_lock ** ddtlock,
+			int do_index)
+{
+	int ssi, next;		/* src slot index */
+	int di;			/* dst entry index */
+	int dsi;		/* dst slot index */
+	s8 *sstbl, *dstbl;	/* sorted entry table */
+	int snamlen, len;
+	struct ldtentry *slh, *dlh = NULL;
+	struct idtentry *sih, *dih = NULL;
+	struct dtslot *h, *s, *d;
+	struct dt_lock *sdtlck = *sdtlock, *ddtlck = *ddtlock;
+	struct lv *slv, *dlv;
+	int xssi, ns, nd;
+	int sfsi;
+
+	sstbl = (s8 *) & sp->slot[sp->header.stblindex];
+	dstbl = (s8 *) & dp->slot[dp->header.stblindex];
+
+	dsi = dp->header.freelist;	/* first (whole page) free slot */
+	sfsi = sp->header.freelist;
+
+	/* linelock destination entry slot */
+	dlv = & ddtlck->lv[ddtlck->index];
+	dlv->offset = dsi;
+
+	/* linelock source entry slot */
+	slv = & sdtlck->lv[sdtlck->index];
+	slv->offset = sstbl[si];
+	xssi = slv->offset - 1;
+
+	/*
+	 * move entries
+	 */
+	ns = nd = 0;
+	for (di = 0; si < sp->header.nextindex; si++, di++) {
+		ssi = sstbl[si];
+		dstbl[di] = dsi;
+
+		/* is next slot contiguous ? */
+		if (ssi != xssi + 1) {
+			/* close current linelock */
+			slv->length = ns;
+			sdtlck->index++;
+
+			/* open new linelock */
+			if (sdtlck->index < sdtlck->maxcnt)
+				slv++;
+			else {
+				sdtlck = (struct dt_lock *) txLinelock(sdtlck);
+				slv = & sdtlck->lv[0];
+			}
+
+			slv->offset = ssi;
+			ns = 0;
+		}
+
+		/*
+		 * move head/only segment of an entry
+		 */
+		/* get dst slot */
+		h = d = &dp->slot[dsi];
+
+		/* get src slot and move */
+		s = &sp->slot[ssi];
+		if (sp->header.flag & BT_LEAF) {
+			/* get source entry */
+			slh = (struct ldtentry *) s;
+			dlh = (struct ldtentry *) h;
+			snamlen = slh->namlen;
+
+			if (do_index) {
+				len = min(snamlen, DTLHDRDATALEN);
+				dlh->index = slh->index; /* little-endian */
+			} else
+				len = min(snamlen, DTLHDRDATALEN_LEGACY);
+
+			memcpy(dlh, slh, 6 + len * 2);
+
+			next = slh->next;
+
+			/* update dst head/only segment next field */
+			dsi++;
+			dlh->next = dsi;
+		} else {
+			sih = (struct idtentry *) s;
+			snamlen = sih->namlen;
+
+			len = min(snamlen, DTIHDRDATALEN);
+			dih = (struct idtentry *) h;
+			memcpy(dih, sih, 10 + len * 2);
+			next = sih->next;
+
+			dsi++;
+			dih->next = dsi;
+		}
+
+		/* free src head/only segment */
+		s->next = sfsi;
+		s->cnt = 1;
+		sfsi = ssi;
+
+		ns++;
+		nd++;
+		xssi = ssi;
+
+		/*
+		 * move additional segment(s) of the entry
+		 */
+		snamlen -= len;
+		while ((ssi = next) >= 0) {
+			/* is next slot contiguous ? */
+			if (ssi != xssi + 1) {
+				/* close current linelock */
+				slv->length = ns;
+				sdtlck->index++;
+
+				/* open new linelock */
+				if (sdtlck->index < sdtlck->maxcnt)
+					slv++;
+				else {
+					sdtlck =
+					    (struct dt_lock *)
+					    txLinelock(sdtlck);
+					slv = & sdtlck->lv[0];
+				}
+
+				slv->offset = ssi;
+				ns = 0;
+			}
+
+			/* get next source segment */
+			s = &sp->slot[ssi];
+
+			/* get next destination free slot */
+			d++;
+
+			len = min(snamlen, DTSLOTDATALEN);
+			UniStrncpy_le(d->name, s->name, len);
+
+			ns++;
+			nd++;
+			xssi = ssi;
+
+			dsi++;
+			d->next = dsi;
+
+			/* free source segment */
+			next = s->next;
+			s->next = sfsi;
+			s->cnt = 1;
+			sfsi = ssi;
+
+			snamlen -= len;
+		}		/* end while */
+
+		/* terminate dst last/only segment */
+		if (h == d) {
+			/* single segment entry */
+			if (dp->header.flag & BT_LEAF)
+				dlh->next = -1;
+			else
+				dih->next = -1;
+		} else
+			/* multi-segment entry */
+			d->next = -1;
+	}			/* end for */
+
+	/* close current linelock */
+	slv->length = ns;
+	sdtlck->index++;
+	*sdtlock = sdtlck;
+
+	dlv->length = nd;
+	ddtlck->index++;
+	*ddtlock = ddtlck;
+
+	/* update source header */
+	sp->header.freelist = sfsi;
+	sp->header.freecnt += nd;
+
+	/* update destination header */
+	dp->header.nextindex = di;
+
+	dp->header.freelist = dsi;
+	dp->header.freecnt -= nd;
+}
+
+
+/*
+ *	dtDeleteEntry()
+ *
+ * function: free a (leaf/internal) entry
+ *
+ * log freelist header, stbl, and each segment slot of entry
+ * (even though last/only segment next field is modified,
+ * physical image logging requires all segment slots of
+ * the entry logged to avoid applying previous updates
+ * to the same slots)
+ */
+static void dtDeleteEntry(dtpage_t * p, int fi, struct dt_lock ** dtlock)
+{
+	int fsi;		/* free entry slot index */
+	s8 *stbl;
+	struct dtslot *t;
+	int si, freecnt;
+	struct dt_lock *dtlck = *dtlock;
+	struct lv *lv;
+	int xsi, n;
+
+	/* get free entry slot index */
+	stbl = DT_GETSTBL(p);
+	fsi = stbl[fi];
+
+	/* open new linelock */
+	if (dtlck->index >= dtlck->maxcnt)
+		dtlck = (struct dt_lock *) txLinelock(dtlck);
+	lv = & dtlck->lv[dtlck->index];
+
+	lv->offset = fsi;
+
+	/* get the head/only segment */
+	t = &p->slot[fsi];
+	if (p->header.flag & BT_LEAF)
+		si = ((struct ldtentry *) t)->next;
+	else
+		si = ((struct idtentry *) t)->next;
+	t->next = si;
+	t->cnt = 1;
+
+	n = freecnt = 1;
+	xsi = fsi;
+
+	/* find the last/only segment */
+	while (si >= 0) {
+		/* is next slot contiguous ? */
+		if (si != xsi + 1) {
+			/* close current linelock */
+			lv->length = n;
+			dtlck->index++;
+
+			/* open new linelock */
+			if (dtlck->index < dtlck->maxcnt)
+				lv++;
+			else {
+				dtlck = (struct dt_lock *) txLinelock(dtlck);
+				lv = & dtlck->lv[0];
+			}
+
+			lv->offset = si;
+			n = 0;
+		}
+
+		n++;
+		xsi = si;
+		freecnt++;
+
+		t = &p->slot[si];
+		t->cnt = 1;
+		si = t->next;
+	}
+
+	/* close current linelock */
+	lv->length = n;
+	dtlck->index++;
+
+	*dtlock = dtlck;
+
+	/* update freelist */
+	t->next = p->header.freelist;
+	p->header.freelist = fsi;
+	p->header.freecnt += freecnt;
+
+	/* if delete from middle,
+	 * shift left the succedding entries in the stbl
+	 */
+	si = p->header.nextindex;
+	if (fi < si - 1)
+		memmove(&stbl[fi], &stbl[fi + 1], si - fi - 1);
+
+	p->header.nextindex--;
+}
+
+
+/*
+ *	dtTruncateEntry()
+ *
+ * function: truncate a (leaf/internal) entry
+ *
+ * log freelist header, stbl, and each segment slot of entry
+ * (even though last/only segment next field is modified,
+ * physical image logging requires all segment slots of
+ * the entry logged to avoid applying previous updates
+ * to the same slots)
+ */
+static void dtTruncateEntry(dtpage_t * p, int ti, struct dt_lock ** dtlock)
+{
+	int tsi;		/* truncate entry slot index */
+	s8 *stbl;
+	struct dtslot *t;
+	int si, freecnt;
+	struct dt_lock *dtlck = *dtlock;
+	struct lv *lv;
+	int fsi, xsi, n;
+
+	/* get free entry slot index */
+	stbl = DT_GETSTBL(p);
+	tsi = stbl[ti];
+
+	/* open new linelock */
+	if (dtlck->index >= dtlck->maxcnt)
+		dtlck = (struct dt_lock *) txLinelock(dtlck);
+	lv = & dtlck->lv[dtlck->index];
+
+	lv->offset = tsi;
+
+	/* get the head/only segment */
+	t = &p->slot[tsi];
+	ASSERT(p->header.flag & BT_INTERNAL);
+	((struct idtentry *) t)->namlen = 0;
+	si = ((struct idtentry *) t)->next;
+	((struct idtentry *) t)->next = -1;
+
+	n = 1;
+	freecnt = 0;
+	fsi = si;
+	xsi = tsi;
+
+	/* find the last/only segment */
+	while (si >= 0) {
+		/* is next slot contiguous ? */
+		if (si != xsi + 1) {
+			/* close current linelock */
+			lv->length = n;
+			dtlck->index++;
+
+			/* open new linelock */
+			if (dtlck->index < dtlck->maxcnt)
+				lv++;
+			else {
+				dtlck = (struct dt_lock *) txLinelock(dtlck);
+				lv = & dtlck->lv[0];
+			}
+
+			lv->offset = si;
+			n = 0;
+		}
+
+		n++;
+		xsi = si;
+		freecnt++;
+
+		t = &p->slot[si];
+		t->cnt = 1;
+		si = t->next;
+	}
+
+	/* close current linelock */
+	lv->length = n;
+	dtlck->index++;
+
+	*dtlock = dtlck;
+
+	/* update freelist */
+	if (freecnt == 0)
+		return;
+	t->next = p->header.freelist;
+	p->header.freelist = fsi;
+	p->header.freecnt += freecnt;
+}
+
+
+/*
+ *	dtLinelockFreelist()
+ */
+static void dtLinelockFreelist(dtpage_t * p,	/* directory page */
+			       int m,	/* max slot index */
+			       struct dt_lock ** dtlock)
+{
+	int fsi;		/* free entry slot index */
+	struct dtslot *t;
+	int si;
+	struct dt_lock *dtlck = *dtlock;
+	struct lv *lv;
+	int xsi, n;
+
+	/* get free entry slot index */
+	fsi = p->header.freelist;
+
+	/* open new linelock */
+	if (dtlck->index >= dtlck->maxcnt)
+		dtlck = (struct dt_lock *) txLinelock(dtlck);
+	lv = & dtlck->lv[dtlck->index];
+
+	lv->offset = fsi;
+
+	n = 1;
+	xsi = fsi;
+
+	t = &p->slot[fsi];
+	si = t->next;
+
+	/* find the last/only segment */
+	while (si < m && si >= 0) {
+		/* is next slot contiguous ? */
+		if (si != xsi + 1) {
+			/* close current linelock */
+			lv->length = n;
+			dtlck->index++;
+
+			/* open new linelock */
+			if (dtlck->index < dtlck->maxcnt)
+				lv++;
+			else {
+				dtlck = (struct dt_lock *) txLinelock(dtlck);
+				lv = & dtlck->lv[0];
+			}
+
+			lv->offset = si;
+			n = 0;
+		}
+
+		n++;
+		xsi = si;
+
+		t = &p->slot[si];
+		si = t->next;
+	}
+
+	/* close current linelock */
+	lv->length = n;
+	dtlck->index++;
+
+	*dtlock = dtlck;
+}
+
+
+/*
+ * NAME: dtModify
+ *
+ * FUNCTION: Modify the inode number part of a directory entry
+ *
+ * PARAMETERS:
+ *	tid	- Transaction id
+ *	ip	- Inode of parent directory
+ *	key	- Name of entry to be modified
+ *	orig_ino	- Original inode number expected in entry
+ *	new_ino	- New inode number to put into entry
+ *	flag	- JFS_RENAME
+ *
+ * RETURNS:
+ *	-ESTALE	- If entry found does not match orig_ino passed in
+ *	-ENOENT	- If no entry can be found to match key
+ *	0	- If successfully modified entry
+ */
+int dtModify(tid_t tid, struct inode *ip,
+	 struct component_name * key, ino_t * orig_ino, ino_t new_ino, int flag)
+{
+	int rc;
+	s64 bn;
+	struct metapage *mp;
+	dtpage_t *p;
+	int index;
+	struct btstack btstack;
+	struct tlock *tlck;
+	struct dt_lock *dtlck;
+	struct lv *lv;
+	s8 *stbl;
+	int entry_si;		/* entry slot index */
+	struct ldtentry *entry;
+
+	/*
+	 *	search for the entry to modify:
+	 *
+	 * dtSearch() returns (leaf page pinned, index at which to modify).
+	 */
+	if ((rc = dtSearch(ip, key, orig_ino, &btstack, flag)))
+		return rc;
+
+	/* retrieve search result */
+	DT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+	BT_MARK_DIRTY(mp, ip);
+	/*
+	 * acquire a transaction lock on the leaf page of named entry
+	 */
+	tlck = txLock(tid, ip, mp, tlckDTREE | tlckENTRY);
+	dtlck = (struct dt_lock *) & tlck->lock;
+
+	/* get slot index of the entry */
+	stbl = DT_GETSTBL(p);
+	entry_si = stbl[index];
+
+	/* linelock entry */
+	ASSERT(dtlck->index == 0);
+	lv = & dtlck->lv[0];
+	lv->offset = entry_si;
+	lv->length = 1;
+	dtlck->index++;
+
+	/* get the head/only segment */
+	entry = (struct ldtentry *) & p->slot[entry_si];
+
+	/* substitute the inode number of the entry */
+	entry->inumber = cpu_to_le32(new_ino);
+
+	/* unpin the leaf page */
+	DT_PUTPAGE(mp);
+
+	return 0;
+}
diff --git a/fs/jfs/jfs_dtree.h b/fs/jfs/jfs_dtree.h
new file mode 100644
index 000000000..175828964
--- /dev/null
+++ b/fs/jfs/jfs_dtree.h
@@ -0,0 +1,256 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ */
+#ifndef _H_JFS_DTREE
+#define	_H_JFS_DTREE
+
+/*
+ *	jfs_dtree.h: directory B+-tree manager
+ */
+
+#include "jfs_btree.h"
+
+typedef union {
+	struct {
+		tid_t tid;
+		struct inode *ip;
+		u32 ino;
+	} leaf;
+	pxd_t xd;
+} ddata_t;
+
+
+/*
+ *	entry segment/slot
+ *
+ * an entry consists of type dependent head/only segment/slot and
+ * additional segments/slots linked vi next field;
+ * N.B. last/only segment of entry is terminated by next = -1;
+ */
+/*
+ *	directory page slot
+ */
+struct dtslot {
+	s8 next;		/* 1: */
+	s8 cnt;			/* 1: */
+	__le16 name[15];	/* 30: */
+};				/* (32) */
+
+
+#define DATASLOTSIZE	16
+#define L2DATASLOTSIZE	4
+#define	DTSLOTSIZE	32
+#define	L2DTSLOTSIZE	5
+#define DTSLOTHDRSIZE	2
+#define DTSLOTDATASIZE	30
+#define DTSLOTDATALEN	15
+
+/*
+ *	 internal node entry head/only segment
+ */
+struct idtentry {
+	pxd_t xd;		/* 8: child extent descriptor */
+
+	s8 next;		/* 1: */
+	u8 namlen;		/* 1: */
+	__le16 name[11];	/* 22: 2-byte aligned */
+};				/* (32) */
+
+#define DTIHDRSIZE	10
+#define DTIHDRDATALEN	11
+
+/* compute number of slots for entry */
+#define	NDTINTERNAL(klen) (DIV_ROUND_UP((4 + (klen)), 15))
+
+
+/*
+ *	leaf node entry head/only segment
+ *
+ *	For legacy filesystems, name contains 13 wchars -- no index field
+ */
+struct ldtentry {
+	__le32 inumber;		/* 4: 4-byte aligned */
+	s8 next;		/* 1: */
+	u8 namlen;		/* 1: */
+	__le16 name[11];	/* 22: 2-byte aligned */
+	__le32 index;		/* 4: index into dir_table */
+};				/* (32) */
+
+#define DTLHDRSIZE	6
+#define DTLHDRDATALEN_LEGACY	13	/* Old (OS/2) format */
+#define DTLHDRDATALEN	11
+
+/*
+ * dir_table used for directory traversal during readdir
+ */
+
+/*
+ * Keep persistent index for directory entries
+ */
+#define DO_INDEX(INODE) (JFS_SBI((INODE)->i_sb)->mntflag & JFS_DIR_INDEX)
+
+/*
+ * Maximum entry in inline directory table
+ */
+#define MAX_INLINE_DIRTABLE_ENTRY 13
+
+struct dir_table_slot {
+	u8 rsrvd;		/* 1: */
+	u8 flag;		/* 1: 0 if free */
+	u8 slot;		/* 1: slot within leaf page of entry */
+	u8 addr1;		/* 1: upper 8 bits of leaf page address */
+	__le32 addr2;		/* 4: lower 32 bits of leaf page address -OR-
+				   index of next entry when this entry was deleted */
+};				/* (8) */
+
+/*
+ * flag values
+ */
+#define DIR_INDEX_VALID 1
+#define DIR_INDEX_FREE 0
+
+#define DTSaddress(dir_table_slot, address64)\
+{\
+	(dir_table_slot)->addr1 = ((u64)address64) >> 32;\
+	(dir_table_slot)->addr2 = __cpu_to_le32((address64) & 0xffffffff);\
+}
+
+#define addressDTS(dts)\
+	( ((s64)((dts)->addr1)) << 32 | __le32_to_cpu((dts)->addr2) )
+
+/* compute number of slots for entry */
+#define	NDTLEAF_LEGACY(klen)	(DIV_ROUND_UP((2 + (klen)), 15))
+#define	NDTLEAF	NDTINTERNAL
+
+
+/*
+ *	directory root page (in-line in on-disk inode):
+ *
+ * cf. dtpage_t below.
+ */
+typedef union {
+	struct {
+		struct dasd DASD; /* 16: DASD limit/usage info */
+
+		u8 flag;	/* 1: */
+		u8 nextindex;	/* 1: next free entry in stbl */
+		s8 freecnt;	/* 1: free count */
+		s8 freelist;	/* 1: freelist header */
+
+		__le32 idotdot;	/* 4: parent inode number */
+
+		s8 stbl[8];	/* 8: sorted entry index table */
+	} header;		/* (32) */
+
+	struct dtslot slot[9];
+} dtroot_t;
+
+#define PARENT(IP) \
+	(le32_to_cpu(JFS_IP(IP)->i_dtroot.header.idotdot))
+
+#define DTROOTMAXSLOT	9
+
+#define	dtEmpty(IP) (JFS_IP(IP)->i_dtroot.header.nextindex == 0)
+
+
+/*
+ *	directory regular page:
+ *
+ *	entry slot array of 32 byte slot
+ *
+ * sorted entry slot index table (stbl):
+ * contiguous slots at slot specified by stblindex,
+ * 1-byte per entry
+ *   512 byte block:  16 entry tbl (1 slot)
+ *  1024 byte block:  32 entry tbl (1 slot)
+ *  2048 byte block:  64 entry tbl (2 slot)
+ *  4096 byte block: 128 entry tbl (4 slot)
+ *
+ * data area:
+ *   512 byte block:  16 - 2 =  14 slot
+ *  1024 byte block:  32 - 2 =  30 slot
+ *  2048 byte block:  64 - 3 =  61 slot
+ *  4096 byte block: 128 - 5 = 123 slot
+ *
+ * N.B. index is 0-based; index fields refer to slot index
+ * except nextindex which refers to entry index in stbl;
+ * end of entry stot list or freelist is marked with -1.
+ */
+typedef union {
+	struct {
+		__le64 next;	/* 8: next sibling */
+		__le64 prev;	/* 8: previous sibling */
+
+		u8 flag;	/* 1: */
+		u8 nextindex;	/* 1: next entry index in stbl */
+		s8 freecnt;	/* 1: */
+		s8 freelist;	/* 1: slot index of head of freelist */
+
+		u8 maxslot;	/* 1: number of slots in page slot[] */
+		u8 stblindex;	/* 1: slot index of start of stbl */
+		u8 rsrvd[2];	/* 2: */
+
+		pxd_t self;	/* 8: self pxd */
+	} header;		/* (32) */
+
+	struct dtslot slot[128];
+} dtpage_t;
+
+#define DTPAGEMAXSLOT        128
+
+#define DT8THPGNODEBYTES     512
+#define DT8THPGNODETSLOTS      1
+#define DT8THPGNODESLOTS      16
+
+#define DTQTRPGNODEBYTES    1024
+#define DTQTRPGNODETSLOTS      1
+#define DTQTRPGNODESLOTS      32
+
+#define DTHALFPGNODEBYTES   2048
+#define DTHALFPGNODETSLOTS     2
+#define DTHALFPGNODESLOTS     64
+
+#define DTFULLPGNODEBYTES   4096
+#define DTFULLPGNODETSLOTS     4
+#define DTFULLPGNODESLOTS    128
+
+#define DTENTRYSTART	1
+
+/* get sorted entry table of the page */
+#define DT_GETSTBL(p) ( ((p)->header.flag & BT_ROOT) ?\
+	((dtroot_t *)(p))->header.stbl : \
+	(s8 *)&(p)->slot[(p)->header.stblindex] )
+
+/*
+ * Flags for dtSearch
+ */
+#define JFS_CREATE 1
+#define JFS_LOOKUP 2
+#define JFS_REMOVE 3
+#define JFS_RENAME 4
+
+/*
+ * Maximum file offset for directories.
+ */
+#define DIREND	INT_MAX
+
+/*
+ *	external declarations
+ */
+extern void dtInitRoot(tid_t tid, struct inode *ip, u32 idotdot);
+
+extern int dtSearch(struct inode *ip, struct component_name * key,
+		    ino_t * data, struct btstack * btstack, int flag);
+
+extern int dtInsert(tid_t tid, struct inode *ip, struct component_name * key,
+		    ino_t * ino, struct btstack * btstack);
+
+extern int dtDelete(tid_t tid, struct inode *ip, struct component_name * key,
+		    ino_t * data, int flag);
+
+extern int dtModify(tid_t tid, struct inode *ip, struct component_name * key,
+		    ino_t * orig_ino, ino_t new_ino, int flag);
+
+extern int jfs_readdir(struct file *file, struct dir_context *ctx);
+#endif				/* !_H_JFS_DTREE */
diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
new file mode 100644
index 000000000..a82751e6c
--- /dev/null
+++ b/fs/jfs/jfs_extent.c
@@ -0,0 +1,388 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+
+#include <linux/fs.h>
+#include <linux/quotaops.h>
+#include "jfs_incore.h"
+#include "jfs_inode.h"
+#include "jfs_superblock.h"
+#include "jfs_dmap.h"
+#include "jfs_extent.h"
+#include "jfs_debug.h"
+
+/*
+ * forward references
+ */
+static int extBalloc(struct inode *, s64, s64 *, s64 *);
+static s64 extRoundDown(s64 nb);
+
+#define DPD(a)		(printk("(a): %d\n",(a)))
+#define DPC(a)		(printk("(a): %c\n",(a)))
+#define DPL1(a)					\
+{						\
+	if ((a) >> 32)				\
+		printk("(a): %x%08x  ",(a));	\
+	else					\
+		printk("(a): %x  ",(a) << 32);	\
+}
+#define DPL(a)					\
+{						\
+	if ((a) >> 32)				\
+		printk("(a): %x%08x\n",(a));	\
+	else					\
+		printk("(a): %x\n",(a) << 32);	\
+}
+
+#define DPD1(a)		(printk("(a): %d  ",(a)))
+#define DPX(a)		(printk("(a): %08x\n",(a)))
+#define DPX1(a)		(printk("(a): %08x  ",(a)))
+#define DPS(a)		(printk("%s\n",(a)))
+#define DPE(a)		(printk("\nENTERING: %s\n",(a)))
+#define DPE1(a)		(printk("\nENTERING: %s",(a)))
+#define DPS1(a)		(printk("  %s  ",(a)))
+
+
+/*
+ * NAME:	extAlloc()
+ *
+ * FUNCTION:	allocate an extent for a specified page range within a
+ *		file.
+ *
+ * PARAMETERS:
+ *	ip	- the inode of the file.
+ *	xlen	- requested extent length.
+ *	pno	- the starting page number with the file.
+ *	xp	- pointer to an xad.  on entry, xad describes an
+ *		  extent that is used as an allocation hint if the
+ *		  xaddr of the xad is non-zero.  on successful exit,
+ *		  the xad describes the newly allocated extent.
+ *	abnr	- bool indicating whether the newly allocated extent
+ *		  should be marked as allocated but not recorded.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error.
+ *	-ENOSPC	- insufficient disk resources.
+ */
+int
+extAlloc(struct inode *ip, s64 xlen, s64 pno, xad_t * xp, bool abnr)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+	s64 nxlen, nxaddr, xoff, hint, xaddr = 0;
+	int rc;
+	int xflag;
+
+	/* This blocks if we are low on resources */
+	txBeginAnon(ip->i_sb);
+
+	/* Avoid race with jfs_commit_inode() */
+	mutex_lock(&JFS_IP(ip)->commit_mutex);
+
+	/* validate extent length */
+	if (xlen > MAXXLEN)
+		xlen = MAXXLEN;
+
+	/* get the page's starting extent offset */
+	xoff = pno << sbi->l2nbperpage;
+
+	/* check if an allocation hint was provided */
+	if ((hint = addressXAD(xp))) {
+		/* get the size of the extent described by the hint */
+		nxlen = lengthXAD(xp);
+
+		/* check if the hint is for the portion of the file
+		 * immediately previous to the current allocation
+		 * request and if hint extent has the same abnr
+		 * value as the current request.  if so, we can
+		 * extend the hint extent to include the current
+		 * extent if we can allocate the blocks immediately
+		 * following the hint extent.
+		 */
+		if (offsetXAD(xp) + nxlen == xoff &&
+		    abnr == ((xp->flag & XAD_NOTRECORDED) ? true : false))
+			xaddr = hint + nxlen;
+
+		/* adjust the hint to the last block of the extent */
+		hint += (nxlen - 1);
+	}
+
+	/* allocate the disk blocks for the extent.  initially, extBalloc()
+	 * will try to allocate disk blocks for the requested size (xlen).
+	 * if this fails (xlen contiguous free blocks not available), it'll
+	 * try to allocate a smaller number of blocks (producing a smaller
+	 * extent), with this smaller number of blocks consisting of the
+	 * requested number of blocks rounded down to the next smaller
+	 * power of 2 number (i.e. 16 -> 8).  it'll continue to round down
+	 * and retry the allocation until the number of blocks to allocate
+	 * is smaller than the number of blocks per page.
+	 */
+	nxlen = xlen;
+	if ((rc = extBalloc(ip, hint ? hint : INOHINT(ip), &nxlen, &nxaddr))) {
+		mutex_unlock(&JFS_IP(ip)->commit_mutex);
+		return (rc);
+	}
+
+	/* Allocate blocks to quota. */
+	rc = dquot_alloc_block(ip, nxlen);
+	if (rc) {
+		dbFree(ip, nxaddr, (s64) nxlen);
+		mutex_unlock(&JFS_IP(ip)->commit_mutex);
+		return rc;
+	}
+
+	/* determine the value of the extent flag */
+	xflag = abnr ? XAD_NOTRECORDED : 0;
+
+	/* if we can extend the hint extent to cover the current request,
+	 * extend it.  otherwise, insert a new extent to
+	 * cover the current request.
+	 */
+	if (xaddr && xaddr == nxaddr)
+		rc = xtExtend(0, ip, xoff, (int) nxlen, 0);
+	else
+		rc = xtInsert(0, ip, xflag, xoff, (int) nxlen, &nxaddr, 0);
+
+	/* if the extend or insert failed,
+	 * free the newly allocated blocks and return the error.
+	 */
+	if (rc) {
+		dbFree(ip, nxaddr, nxlen);
+		dquot_free_block(ip, nxlen);
+		mutex_unlock(&JFS_IP(ip)->commit_mutex);
+		return (rc);
+	}
+
+	/* set the results of the extent allocation */
+	XADaddress(xp, nxaddr);
+	XADlength(xp, nxlen);
+	XADoffset(xp, xoff);
+	xp->flag = xflag;
+
+	mark_inode_dirty(ip);
+
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	/*
+	 * COMMIT_SyncList flags an anonymous tlock on page that is on
+	 * sync list.
+	 * We need to commit the inode to get the page written disk.
+	 */
+	if (test_and_clear_cflag(COMMIT_Synclist,ip))
+		jfs_commit_inode(ip, 0);
+
+	return (0);
+}
+
+/*
+ * NAME:	extHint()
+ *
+ * FUNCTION:	produce an extent allocation hint for a file offset.
+ *
+ * PARAMETERS:
+ *	ip	- the inode of the file.
+ *	offset  - file offset for which the hint is needed.
+ *	xp	- pointer to the xad that is to be filled in with
+ *		  the hint.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error.
+ */
+int extHint(struct inode *ip, s64 offset, xad_t * xp)
+{
+	struct super_block *sb = ip->i_sb;
+	int nbperpage = JFS_SBI(sb)->nbperpage;
+	s64 prev;
+	int rc = 0;
+	s64 xaddr;
+	int xlen;
+	int xflag;
+
+	/* init the hint as "no hint provided" */
+	XADaddress(xp, 0);
+
+	/* determine the starting extent offset of the page previous
+	 * to the page containing the offset.
+	 */
+	prev = ((offset & ~POFFSET) >> JFS_SBI(sb)->l2bsize) - nbperpage;
+
+	/* if the offset is in the first page of the file, no hint provided.
+	 */
+	if (prev < 0)
+		goto out;
+
+	rc = xtLookup(ip, prev, nbperpage, &xflag, &xaddr, &xlen, 0);
+
+	if ((rc == 0) && xlen) {
+		if (xlen != nbperpage) {
+			jfs_error(ip->i_sb, "corrupt xtree\n");
+			rc = -EIO;
+		}
+		XADaddress(xp, xaddr);
+		XADlength(xp, xlen);
+		XADoffset(xp, prev);
+		/*
+		 * only preserve the abnr flag within the xad flags
+		 * of the returned hint.
+		 */
+		xp->flag  = xflag & XAD_NOTRECORDED;
+	} else
+		rc = 0;
+
+out:
+	return (rc);
+}
+
+
+/*
+ * NAME:	extRecord()
+ *
+ * FUNCTION:	change a page with a file from not recorded to recorded.
+ *
+ * PARAMETERS:
+ *	ip	- inode of the file.
+ *	cp	- cbuf of the file page.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error.
+ *	-ENOSPC	- insufficient disk resources.
+ */
+int extRecord(struct inode *ip, xad_t * xp)
+{
+	int rc;
+
+	txBeginAnon(ip->i_sb);
+
+	mutex_lock(&JFS_IP(ip)->commit_mutex);
+
+	/* update the extent */
+	rc = xtUpdate(0, ip, xp);
+
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	return rc;
+}
+
+/*
+ * NAME:	extBalloc()
+ *
+ * FUNCTION:	allocate disk blocks to form an extent.
+ *
+ *		initially, we will try to allocate disk blocks for the
+ *		requested size (nblocks).  if this fails (nblocks
+ *		contiguous free blocks not available), we'll try to allocate
+ *		a smaller number of blocks (producing a smaller extent), with
+ *		this smaller number of blocks consisting of the requested
+ *		number of blocks rounded down to the next smaller power of 2
+ *		number (i.e. 16 -> 8).  we'll continue to round down and
+ *		retry the allocation until the number of blocks to allocate
+ *		is smaller than the number of blocks per page.
+ *
+ * PARAMETERS:
+ *	ip	 - the inode of the file.
+ *	hint	 - disk block number to be used as an allocation hint.
+ *	*nblocks - pointer to an s64 value.  on entry, this value specifies
+ *		   the desired number of block to be allocated. on successful
+ *		   exit, this value is set to the number of blocks actually
+ *		   allocated.
+ *	blkno	 - pointer to a block address that is filled in on successful
+ *		   return with the starting block number of the newly
+ *		   allocated block range.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error.
+ *	-ENOSPC	- insufficient disk resources.
+ */
+static int
+extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
+{
+	struct jfs_inode_info *ji = JFS_IP(ip);
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+	s64 nb, nblks, daddr, max;
+	int rc, nbperpage = sbi->nbperpage;
+	struct bmap *bmp = sbi->bmap;
+	int ag;
+
+	/* get the number of blocks to initially attempt to allocate.
+	 * we'll first try the number of blocks requested unless this
+	 * number is greater than the maximum number of contiguous free
+	 * blocks in the map. in that case, we'll start off with the
+	 * maximum free.
+	 */
+
+	/* give up if no space left */
+	if (bmp->db_maxfreebud == -1)
+		return -ENOSPC;
+
+	max = (s64) 1 << bmp->db_maxfreebud;
+	if (*nblocks >= max && *nblocks > nbperpage)
+		nb = nblks = (max > nbperpage) ? max : nbperpage;
+	else
+		nb = nblks = *nblocks;
+
+	/* try to allocate blocks */
+	while ((rc = dbAlloc(ip, hint, nb, &daddr)) != 0) {
+		/* if something other than an out of space error,
+		 * stop and return this error.
+		 */
+		if (rc != -ENOSPC)
+			return (rc);
+
+		/* decrease the allocation request size */
+		nb = min(nblks, extRoundDown(nb));
+
+		/* give up if we cannot cover a page */
+		if (nb < nbperpage)
+			return (rc);
+	}
+
+	*nblocks = nb;
+	*blkno = daddr;
+
+	if (S_ISREG(ip->i_mode) && (ji->fileset == FILESYSTEM_I)) {
+		ag = BLKTOAG(daddr, sbi);
+		spin_lock_irq(&ji->ag_lock);
+		if (ji->active_ag == -1) {
+			atomic_inc(&bmp->db_active[ag]);
+			ji->active_ag = ag;
+		} else if (ji->active_ag != ag) {
+			atomic_dec(&bmp->db_active[ji->active_ag]);
+			atomic_inc(&bmp->db_active[ag]);
+			ji->active_ag = ag;
+		}
+		spin_unlock_irq(&ji->ag_lock);
+	}
+
+	return (0);
+}
+
+/*
+ * NAME:	extRoundDown()
+ *
+ * FUNCTION:	round down a specified number of blocks to the next
+ *		smallest power of 2 number.
+ *
+ * PARAMETERS:
+ *	nb	- the inode of the file.
+ *
+ * RETURN VALUES:
+ *	next smallest power of 2 number.
+ */
+static s64 extRoundDown(s64 nb)
+{
+	int i;
+	u64 m, k;
+
+	for (i = 0, m = (u64) 1 << 63; i < 64; i++, m >>= 1) {
+		if (m & nb)
+			break;
+	}
+
+	i = 63 - i;
+	k = (u64) 1 << i;
+	k = ((k - 1) & nb) ? k : k >> 1;
+
+	return (k);
+}
diff --git a/fs/jfs/jfs_extent.h b/fs/jfs/jfs_extent.h
new file mode 100644
index 000000000..1c984214e
--- /dev/null
+++ b/fs/jfs/jfs_extent.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2001
+ */
+#ifndef	_H_JFS_EXTENT
+#define _H_JFS_EXTENT
+
+/*  get block allocation hint as location of disk inode */
+#define	INOHINT(ip)	\
+	(addressPXD(&(JFS_IP(ip)->ixpxd)) + lengthPXD(&(JFS_IP(ip)->ixpxd)) - 1)
+
+extern int	extAlloc(struct inode *, s64, s64, xad_t *, bool);
+extern int	extFill(struct inode *, xad_t *);
+extern int	extHint(struct inode *, s64, xad_t *);
+extern int	extRealloc(struct inode *, s64, xad_t *, bool);
+extern int	extRecord(struct inode *, xad_t *);
+
+#endif	/* _H_JFS_EXTENT */
diff --git a/fs/jfs/jfs_filsys.h b/fs/jfs/jfs_filsys.h
new file mode 100644
index 000000000..33ef13a0b
--- /dev/null
+++ b/fs/jfs/jfs_filsys.h
@@ -0,0 +1,275 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2003
+ */
+#ifndef _H_JFS_FILSYS
+#define _H_JFS_FILSYS
+
+/*
+ *	jfs_filsys.h
+ *
+ * file system (implementation-dependent) constants
+ *
+ * refer to <limits.h> for system wide implementation-dependent constants
+ */
+
+/*
+ *	 file system option (superblock flag)
+ */
+
+/* directory option */
+#define JFS_UNICODE	0x00000001	/* unicode name */
+
+/* mount time flags for error handling */
+#define JFS_ERR_REMOUNT_RO 0x00000002	/* remount read-only */
+#define JFS_ERR_CONTINUE   0x00000004	/* continue */
+#define JFS_ERR_PANIC      0x00000008	/* panic */
+
+/* Quota support */
+#define	JFS_USRQUOTA	0x00000010
+#define	JFS_GRPQUOTA	0x00000020
+
+/* mount time flag to disable journaling to disk */
+#define JFS_NOINTEGRITY 0x00000040
+
+/* mount time flag to enable TRIM to ssd disks */
+#define JFS_DISCARD     0x00000080
+
+/* commit option */
+#define	JFS_COMMIT	0x00000f00	/* commit option mask */
+#define	JFS_GROUPCOMMIT	0x00000100	/* group (of 1) commit */
+#define	JFS_LAZYCOMMIT	0x00000200	/* lazy commit */
+#define	JFS_TMPFS	0x00000400	/* temporary file system -
+					 * do not log/commit:
+					 * Never implemented
+					 */
+
+/* log logical volume option */
+#define	JFS_INLINELOG	0x00000800	/* inline log within file system */
+#define JFS_INLINEMOVE	0x00001000	/* inline log being moved */
+
+/* Secondary aggregate inode table */
+#define JFS_BAD_SAIT	0x00010000	/* current secondary ait is bad */
+
+/* sparse regular file support */
+#define JFS_SPARSE	0x00020000	/* sparse regular file */
+
+/* DASD Limits		F226941 */
+#define JFS_DASD_ENABLED 0x00040000	/* DASD limits enabled */
+#define	JFS_DASD_PRIME	0x00080000	/* Prime DASD usage on boot */
+
+/* big endian flag */
+#define	JFS_SWAP_BYTES	0x00100000	/* running on big endian computer */
+
+/* Directory index */
+#define JFS_DIR_INDEX	0x00200000	/* Persistent index for */
+
+/* platform options */
+#define JFS_LINUX	0x10000000	/* Linux support */
+#define JFS_DFS		0x20000000	/* DCE DFS LFS support */
+/*	Never implemented */
+
+#define JFS_OS2		0x40000000	/* OS/2 support */
+/*	case-insensitive name/directory support */
+
+#define JFS_AIX		0x80000000	/* AIX support */
+
+/*
+ *	buffer cache configuration
+ */
+/* page size */
+#ifdef PSIZE
+#undef PSIZE
+#endif
+#define	PSIZE		4096	/* page size (in byte) */
+#define	L2PSIZE		12	/* log2(PSIZE) */
+#define	POFFSET		4095	/* offset within page */
+
+/* buffer page size */
+#define BPSIZE	PSIZE
+
+/*
+ *	fs fundamental size
+ *
+ * PSIZE >= file system block size >= PBSIZE >= DISIZE
+ */
+#define	PBSIZE		512	/* physical block size (in byte) */
+#define	L2PBSIZE	9	/* log2(PBSIZE) */
+
+#define DISIZE		512	/* on-disk inode size (in byte) */
+#define L2DISIZE	9	/* log2(DISIZE) */
+
+#define IDATASIZE	256	/* inode inline data size */
+#define	IXATTRSIZE	128	/* inode inline extended attribute size */
+
+#define XTPAGE_SIZE	4096
+#define log2_PAGESIZE	12
+
+#define IAG_SIZE	4096
+#define IAG_EXTENT_SIZE 4096
+#define	INOSPERIAG	4096	/* number of disk inodes per iag */
+#define	L2INOSPERIAG	12	/* l2 number of disk inodes per iag */
+#define INOSPEREXT	32	/* number of disk inode per extent */
+#define L2INOSPEREXT	5	/* l2 number of disk inode per extent */
+#define	IXSIZE		(DISIZE * INOSPEREXT)	/* inode extent size */
+#define	INOSPERPAGE	8	/* number of disk inodes per 4K page */
+#define	L2INOSPERPAGE	3	/* log2(INOSPERPAGE) */
+
+#define	IAGFREELIST_LWM	64
+
+#define INODE_EXTENT_SIZE	IXSIZE	/* inode extent size */
+#define NUM_INODE_PER_EXTENT	INOSPEREXT
+#define NUM_INODE_PER_IAG	INOSPERIAG
+
+#define MINBLOCKSIZE		512
+#define L2MINBLOCKSIZE		9
+#define MAXBLOCKSIZE		4096
+#define L2MAXBLOCKSIZE		12
+#define	MAXFILESIZE		((s64)1 << 52)
+
+#define JFS_LINK_MAX		0xffffffff
+
+/* Minimum number of bytes supported for a JFS partition */
+#define MINJFS			(0x1000000)
+#define MINJFSTEXT		"16"
+
+/*
+ * file system block size -> physical block size
+ */
+#define LBOFFSET(x)	((x) & (PBSIZE - 1))
+#define LBNUMBER(x)	((x) >> L2PBSIZE)
+#define	LBLK2PBLK(sb,b)	((b) << (sb->s_blocksize_bits - L2PBSIZE))
+#define	PBLK2LBLK(sb,b)	((b) >> (sb->s_blocksize_bits - L2PBSIZE))
+/* size in byte -> last page number */
+#define	SIZE2PN(size)	( ((s64)((size) - 1)) >> (L2PSIZE) )
+/* size in byte -> last file system block number */
+#define	SIZE2BN(size, l2bsize) ( ((s64)((size) - 1)) >> (l2bsize) )
+
+/*
+ * fixed physical block address (physical block size = 512 byte)
+ *
+ * NOTE: since we can't guarantee a physical block size of 512 bytes the use of
+ *	 these macros should be removed and the byte offset macros used instead.
+ */
+#define SUPER1_B	64	/* primary superblock */
+#define	AIMAP_B		(SUPER1_B + 8)	/* 1st extent of aggregate inode map */
+#define	AITBL_B		(AIMAP_B + 16)	/*
+					 * 1st extent of aggregate inode table
+					 */
+#define	SUPER2_B	(AITBL_B + 32)	/* 2ndary superblock pbn */
+#define	BMAP_B		(SUPER2_B + 8)	/* block allocation map */
+
+/*
+ * SIZE_OF_SUPER defines the total amount of space reserved on disk for the
+ * superblock.  This is not the same as the superblock structure, since all of
+ * this space is not currently being used.
+ */
+#define SIZE_OF_SUPER	PSIZE
+
+/*
+ * SIZE_OF_AG_TABLE defines the amount of space reserved to hold the AG table
+ */
+#define SIZE_OF_AG_TABLE	PSIZE
+
+/*
+ * SIZE_OF_MAP_PAGE defines the amount of disk space reserved for each page of
+ * the inode allocation map (to hold iag)
+ */
+#define SIZE_OF_MAP_PAGE	PSIZE
+
+/*
+ * fixed byte offset address
+ */
+#define SUPER1_OFF	0x8000	/* primary superblock */
+#define AIMAP_OFF	(SUPER1_OFF + SIZE_OF_SUPER)
+					/*
+					 * Control page of aggregate inode map
+					 * followed by 1st extent of map
+					 */
+#define AITBL_OFF	(AIMAP_OFF + (SIZE_OF_MAP_PAGE << 1))
+					/*
+					 * 1st extent of aggregate inode table
+					 */
+#define SUPER2_OFF	(AITBL_OFF + INODE_EXTENT_SIZE)
+					/*
+					 * secondary superblock
+					 */
+#define BMAP_OFF	(SUPER2_OFF + SIZE_OF_SUPER)
+					/*
+					 * block allocation map
+					 */
+
+/*
+ * The following macro is used to indicate the number of reserved disk blocks at
+ * the front of an aggregate, in terms of physical blocks.  This value is
+ * currently defined to be 32K.  This turns out to be the same as the primary
+ * superblock's address, since it directly follows the reserved blocks.
+ */
+#define AGGR_RSVD_BLOCKS	SUPER1_B
+
+/*
+ * The following macro is used to indicate the number of reserved bytes at the
+ * front of an aggregate.  This value is currently defined to be 32K.  This
+ * turns out to be the same as the primary superblock's byte offset, since it
+ * directly follows the reserved blocks.
+ */
+#define AGGR_RSVD_BYTES	SUPER1_OFF
+
+/*
+ * The following macro defines the byte offset for the first inode extent in
+ * the aggregate inode table.  This allows us to find the self inode to find the
+ * rest of the table.  Currently this value is 44K.
+ */
+#define AGGR_INODE_TABLE_START	AITBL_OFF
+
+/*
+ *	fixed reserved inode number
+ */
+/* aggregate inode */
+#define AGGR_RESERVED_I	0	/* aggregate inode (reserved) */
+#define	AGGREGATE_I	1	/* aggregate inode map inode */
+#define	BMAP_I		2	/* aggregate block allocation map inode */
+#define	LOG_I		3	/* aggregate inline log inode */
+#define BADBLOCK_I	4	/* aggregate bad block inode */
+#define	FILESYSTEM_I	16	/* 1st/only fileset inode in ait:
+				 * fileset inode map inode
+				 */
+
+/* per fileset inode */
+#define FILESET_RSVD_I	0	/* fileset inode (reserved) */
+#define FILESET_EXT_I	1	/* fileset inode extension */
+#define	ROOT_I		2	/* fileset root inode */
+#define ACL_I		3	/* fileset ACL inode */
+
+#define FILESET_OBJECT_I 4	/* the first fileset inode available for a file
+				 * or directory or link...
+				 */
+#define FIRST_FILESET_INO 16	/* the first aggregate inode which describes
+				 * an inode.  (To fsck this is also the first
+				 * inode in part 2 of the agg inode table.)
+				 */
+
+/*
+ *	directory configuration
+ */
+#define JFS_NAME_MAX	255
+#define JFS_PATH_MAX	BPSIZE
+
+
+/*
+ *	file system state (superblock state)
+ */
+#define FM_CLEAN 0x00000000	/* file system is unmounted and clean */
+#define FM_MOUNT 0x00000001	/* file system is mounted cleanly */
+#define FM_DIRTY 0x00000002	/* file system was not unmounted and clean
+				 * when mounted or
+				 * commit failure occurred while being mounted:
+				 * fsck() must be run to repair
+				 */
+#define	FM_LOGREDO 0x00000004	/* log based recovery (logredo()) failed:
+				 * fsck() must be run to repair
+				 */
+#define	FM_EXTENDFS 0x00000008	/* file system extendfs() in progress */
+#define	FM_STATE_MAX 0x0000000f	/* max value of s_state */
+
+#endif				/* _H_JFS_FILSYS */
diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c
new file mode 100644
index 000000000..6ed2e1d4c
--- /dev/null
+++ b/fs/jfs/jfs_imap.c
@@ -0,0 +1,3159 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+
+/*
+ *	jfs_imap.c: inode allocation map manager
+ *
+ * Serialization:
+ *   Each AG has a simple lock which is used to control the serialization of
+ *	the AG level lists.  This lock should be taken first whenever an AG
+ *	level list will be modified or accessed.
+ *
+ *   Each IAG is locked by obtaining the buffer for the IAG page.
+ *
+ *   There is also a inode lock for the inode map inode.  A read lock needs to
+ *	be taken whenever an IAG is read from the map or the global level
+ *	information is read.  A write lock needs to be taken whenever the global
+ *	level information is modified or an atomic operation needs to be used.
+ *
+ *	If more than one IAG is read at one time, the read lock may not
+ *	be given up until all of the IAG's are read.  Otherwise, a deadlock
+ *	may occur when trying to obtain the read lock while another thread
+ *	holding the read lock is waiting on the IAG already being held.
+ *
+ *   The control page of the inode map is read into memory by diMount().
+ *	Thereafter it should only be modified in memory and then it will be
+ *	written out when the filesystem is unmounted by diUnmount().
+ */
+
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include <linux/pagemap.h>
+#include <linux/quotaops.h>
+#include <linux/slab.h>
+
+#include "jfs_incore.h"
+#include "jfs_inode.h"
+#include "jfs_filsys.h"
+#include "jfs_dinode.h"
+#include "jfs_dmap.h"
+#include "jfs_imap.h"
+#include "jfs_metapage.h"
+#include "jfs_superblock.h"
+#include "jfs_debug.h"
+
+/*
+ * imap locks
+ */
+/* iag free list lock */
+#define IAGFREE_LOCK_INIT(imap)		mutex_init(&imap->im_freelock)
+#define IAGFREE_LOCK(imap)		mutex_lock(&imap->im_freelock)
+#define IAGFREE_UNLOCK(imap)		mutex_unlock(&imap->im_freelock)
+
+/* per ag iag list locks */
+#define AG_LOCK_INIT(imap,index)	mutex_init(&(imap->im_aglock[index]))
+#define AG_LOCK(imap,agno)		mutex_lock(&imap->im_aglock[agno])
+#define AG_UNLOCK(imap,agno)		mutex_unlock(&imap->im_aglock[agno])
+
+/*
+ * forward references
+ */
+static int diAllocAG(struct inomap *, int, bool, struct inode *);
+static int diAllocAny(struct inomap *, int, bool, struct inode *);
+static int diAllocBit(struct inomap *, struct iag *, int);
+static int diAllocExt(struct inomap *, int, struct inode *);
+static int diAllocIno(struct inomap *, int, struct inode *);
+static int diFindFree(u32, int);
+static int diNewExt(struct inomap *, struct iag *, int);
+static int diNewIAG(struct inomap *, int *, int, struct metapage **);
+static void duplicateIXtree(struct super_block *, s64, int, s64 *);
+
+static int diIAGRead(struct inomap * imap, int, struct metapage **);
+static int copy_from_dinode(struct dinode *, struct inode *);
+static void copy_to_dinode(struct dinode *, struct inode *);
+
+/*
+ * NAME:	diMount()
+ *
+ * FUNCTION:	initialize the incore inode map control structures for
+ *		a fileset or aggregate init time.
+ *
+ *		the inode map's control structure (dinomap) is
+ *		brought in from disk and placed in virtual memory.
+ *
+ * PARAMETERS:
+ *	ipimap	- pointer to inode map inode for the aggregate or fileset.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOMEM	- insufficient free virtual memory.
+ *	-EIO	- i/o error.
+ */
+int diMount(struct inode *ipimap)
+{
+	struct inomap *imap;
+	struct metapage *mp;
+	int index;
+	struct dinomap_disk *dinom_le;
+
+	/*
+	 * allocate/initialize the in-memory inode map control structure
+	 */
+	/* allocate the in-memory inode map control structure. */
+	imap = kmalloc(sizeof(struct inomap), GFP_KERNEL);
+	if (imap == NULL)
+		return -ENOMEM;
+
+	/* read the on-disk inode map control structure. */
+
+	mp = read_metapage(ipimap,
+			   IMAPBLKNO << JFS_SBI(ipimap->i_sb)->l2nbperpage,
+			   PSIZE, 0);
+	if (mp == NULL) {
+		kfree(imap);
+		return -EIO;
+	}
+
+	/* copy the on-disk version to the in-memory version. */
+	dinom_le = (struct dinomap_disk *) mp->data;
+	imap->im_freeiag = le32_to_cpu(dinom_le->in_freeiag);
+	imap->im_nextiag = le32_to_cpu(dinom_le->in_nextiag);
+	atomic_set(&imap->im_numinos, le32_to_cpu(dinom_le->in_numinos));
+	atomic_set(&imap->im_numfree, le32_to_cpu(dinom_le->in_numfree));
+	imap->im_nbperiext = le32_to_cpu(dinom_le->in_nbperiext);
+	imap->im_l2nbperiext = le32_to_cpu(dinom_le->in_l2nbperiext);
+	for (index = 0; index < MAXAG; index++) {
+		imap->im_agctl[index].inofree =
+		    le32_to_cpu(dinom_le->in_agctl[index].inofree);
+		imap->im_agctl[index].extfree =
+		    le32_to_cpu(dinom_le->in_agctl[index].extfree);
+		imap->im_agctl[index].numinos =
+		    le32_to_cpu(dinom_le->in_agctl[index].numinos);
+		imap->im_agctl[index].numfree =
+		    le32_to_cpu(dinom_le->in_agctl[index].numfree);
+	}
+
+	/* release the buffer. */
+	release_metapage(mp);
+
+	/*
+	 * allocate/initialize inode allocation map locks
+	 */
+	/* allocate and init iag free list lock */
+	IAGFREE_LOCK_INIT(imap);
+
+	/* allocate and init ag list locks */
+	for (index = 0; index < MAXAG; index++) {
+		AG_LOCK_INIT(imap, index);
+	}
+
+	/* bind the inode map inode and inode map control structure
+	 * to each other.
+	 */
+	imap->im_ipimap = ipimap;
+	JFS_IP(ipimap)->i_imap = imap;
+
+	return (0);
+}
+
+
+/*
+ * NAME:	diUnmount()
+ *
+ * FUNCTION:	write to disk the incore inode map control structures for
+ *		a fileset or aggregate at unmount time.
+ *
+ * PARAMETERS:
+ *	ipimap	- pointer to inode map inode for the aggregate or fileset.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOMEM	- insufficient free virtual memory.
+ *	-EIO	- i/o error.
+ */
+int diUnmount(struct inode *ipimap, int mounterror)
+{
+	struct inomap *imap = JFS_IP(ipimap)->i_imap;
+
+	/*
+	 * update the on-disk inode map control structure
+	 */
+
+	if (!(mounterror || isReadOnly(ipimap)))
+		diSync(ipimap);
+
+	/*
+	 * Invalidate the page cache buffers
+	 */
+	truncate_inode_pages(ipimap->i_mapping, 0);
+
+	/*
+	 * free in-memory control structure
+	 */
+	kfree(imap);
+	JFS_IP(ipimap)->i_imap = NULL;
+
+	return (0);
+}
+
+
+/*
+ *	diSync()
+ */
+int diSync(struct inode *ipimap)
+{
+	struct dinomap_disk *dinom_le;
+	struct inomap *imp = JFS_IP(ipimap)->i_imap;
+	struct metapage *mp;
+	int index;
+
+	/*
+	 * write imap global conrol page
+	 */
+	/* read the on-disk inode map control structure */
+	mp = get_metapage(ipimap,
+			  IMAPBLKNO << JFS_SBI(ipimap->i_sb)->l2nbperpage,
+			  PSIZE, 0);
+	if (mp == NULL) {
+		jfs_err("diSync: get_metapage failed!");
+		return -EIO;
+	}
+
+	/* copy the in-memory version to the on-disk version */
+	dinom_le = (struct dinomap_disk *) mp->data;
+	dinom_le->in_freeiag = cpu_to_le32(imp->im_freeiag);
+	dinom_le->in_nextiag = cpu_to_le32(imp->im_nextiag);
+	dinom_le->in_numinos = cpu_to_le32(atomic_read(&imp->im_numinos));
+	dinom_le->in_numfree = cpu_to_le32(atomic_read(&imp->im_numfree));
+	dinom_le->in_nbperiext = cpu_to_le32(imp->im_nbperiext);
+	dinom_le->in_l2nbperiext = cpu_to_le32(imp->im_l2nbperiext);
+	for (index = 0; index < MAXAG; index++) {
+		dinom_le->in_agctl[index].inofree =
+		    cpu_to_le32(imp->im_agctl[index].inofree);
+		dinom_le->in_agctl[index].extfree =
+		    cpu_to_le32(imp->im_agctl[index].extfree);
+		dinom_le->in_agctl[index].numinos =
+		    cpu_to_le32(imp->im_agctl[index].numinos);
+		dinom_le->in_agctl[index].numfree =
+		    cpu_to_le32(imp->im_agctl[index].numfree);
+	}
+
+	/* write out the control structure */
+	write_metapage(mp);
+
+	/*
+	 * write out dirty pages of imap
+	 */
+	filemap_write_and_wait(ipimap->i_mapping);
+
+	diWriteSpecial(ipimap, 0);
+
+	return (0);
+}
+
+
+/*
+ * NAME:	diRead()
+ *
+ * FUNCTION:	initialize an incore inode from disk.
+ *
+ *		on entry, the specifed incore inode should itself
+ *		specify the disk inode number corresponding to the
+ *		incore inode (i.e. i_number should be initialized).
+ *
+ *		this routine handles incore inode initialization for
+ *		both "special" and "regular" inodes.  special inodes
+ *		are those required early in the mount process and
+ *		require special handling since much of the file system
+ *		is not yet initialized.  these "special" inodes are
+ *		identified by a NULL inode map inode pointer and are
+ *		actually initialized by a call to diReadSpecial().
+ *
+ *		for regular inodes, the iag describing the disk inode
+ *		is read from disk to determine the inode extent address
+ *		for the disk inode.  with the inode extent address in
+ *		hand, the page of the extent that contains the disk
+ *		inode is read and the disk inode is copied to the
+ *		incore inode.
+ *
+ * PARAMETERS:
+ *	ip	-  pointer to incore inode to be initialized from disk.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error.
+ *	-ENOMEM	- insufficient memory
+ *
+ */
+int diRead(struct inode *ip)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+	int iagno, ino, extno, rc;
+	struct inode *ipimap;
+	struct dinode *dp;
+	struct iag *iagp;
+	struct metapage *mp;
+	s64 blkno, agstart;
+	struct inomap *imap;
+	int block_offset;
+	int inodes_left;
+	unsigned long pageno;
+	int rel_inode;
+
+	jfs_info("diRead: ino = %ld", ip->i_ino);
+
+	ipimap = sbi->ipimap;
+	JFS_IP(ip)->ipimap = ipimap;
+
+	/* determine the iag number for this inode (number) */
+	iagno = INOTOIAG(ip->i_ino);
+
+	/* read the iag */
+	imap = JFS_IP(ipimap)->i_imap;
+	IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
+	rc = diIAGRead(imap, iagno, &mp);
+	IREAD_UNLOCK(ipimap);
+	if (rc) {
+		jfs_err("diRead: diIAGRead returned %d", rc);
+		return (rc);
+	}
+
+	iagp = (struct iag *) mp->data;
+
+	/* determine inode extent that holds the disk inode */
+	ino = ip->i_ino & (INOSPERIAG - 1);
+	extno = ino >> L2INOSPEREXT;
+
+	if ((lengthPXD(&iagp->inoext[extno]) != imap->im_nbperiext) ||
+	    (addressPXD(&iagp->inoext[extno]) == 0)) {
+		release_metapage(mp);
+		return -ESTALE;
+	}
+
+	/* get disk block number of the page within the inode extent
+	 * that holds the disk inode.
+	 */
+	blkno = INOPBLK(&iagp->inoext[extno], ino, sbi->l2nbperpage);
+
+	/* get the ag for the iag */
+	agstart = le64_to_cpu(iagp->agstart);
+
+	release_metapage(mp);
+
+	rel_inode = (ino & (INOSPERPAGE - 1));
+	pageno = blkno >> sbi->l2nbperpage;
+
+	if ((block_offset = ((u32) blkno & (sbi->nbperpage - 1)))) {
+		/*
+		 * OS/2 didn't always align inode extents on page boundaries
+		 */
+		inodes_left =
+		     (sbi->nbperpage - block_offset) << sbi->l2niperblk;
+
+		if (rel_inode < inodes_left)
+			rel_inode += block_offset << sbi->l2niperblk;
+		else {
+			pageno += 1;
+			rel_inode -= inodes_left;
+		}
+	}
+
+	/* read the page of disk inode */
+	mp = read_metapage(ipimap, pageno << sbi->l2nbperpage, PSIZE, 1);
+	if (!mp) {
+		jfs_err("diRead: read_metapage failed");
+		return -EIO;
+	}
+
+	/* locate the disk inode requested */
+	dp = (struct dinode *) mp->data;
+	dp += rel_inode;
+
+	if (ip->i_ino != le32_to_cpu(dp->di_number)) {
+		jfs_error(ip->i_sb, "i_ino != di_number\n");
+		rc = -EIO;
+	} else if (le32_to_cpu(dp->di_nlink) == 0)
+		rc = -ESTALE;
+	else
+		/* copy the disk inode to the in-memory inode */
+		rc = copy_from_dinode(dp, ip);
+
+	release_metapage(mp);
+
+	/* set the ag for the inode */
+	JFS_IP(ip)->agstart = agstart;
+	JFS_IP(ip)->active_ag = -1;
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	diReadSpecial()
+ *
+ * FUNCTION:	initialize a 'special' inode from disk.
+ *
+ *		this routines handles aggregate level inodes.  The
+ *		inode cache cannot differentiate between the
+ *		aggregate inodes and the filesystem inodes, so we
+ *		handle these here.  We don't actually use the aggregate
+ *		inode map, since these inodes are at a fixed location
+ *		and in some cases the aggregate inode map isn't initialized
+ *		yet.
+ *
+ * PARAMETERS:
+ *	sb - filesystem superblock
+ *	inum - aggregate inode number
+ *	secondary - 1 if secondary aggregate inode table
+ *
+ * RETURN VALUES:
+ *	new inode	- success
+ *	NULL		- i/o error.
+ */
+struct inode *diReadSpecial(struct super_block *sb, ino_t inum, int secondary)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	uint address;
+	struct dinode *dp;
+	struct inode *ip;
+	struct metapage *mp;
+
+	ip = new_inode(sb);
+	if (ip == NULL) {
+		jfs_err("diReadSpecial: new_inode returned NULL!");
+		return ip;
+	}
+
+	if (secondary) {
+		address = addressPXD(&sbi->ait2) >> sbi->l2nbperpage;
+		JFS_IP(ip)->ipimap = sbi->ipaimap2;
+	} else {
+		address = AITBL_OFF >> L2PSIZE;
+		JFS_IP(ip)->ipimap = sbi->ipaimap;
+	}
+
+	ASSERT(inum < INOSPEREXT);
+
+	ip->i_ino = inum;
+
+	address += inum >> 3;	/* 8 inodes per 4K page */
+
+	/* read the page of fixed disk inode (AIT) in raw mode */
+	mp = read_metapage(ip, address << sbi->l2nbperpage, PSIZE, 1);
+	if (mp == NULL) {
+		set_nlink(ip, 1);	/* Don't want iput() deleting it */
+		iput(ip);
+		return (NULL);
+	}
+
+	/* get the pointer to the disk inode of interest */
+	dp = (struct dinode *) (mp->data);
+	dp += inum % 8;		/* 8 inodes per 4K page */
+
+	/* copy on-disk inode to in-memory inode */
+	if ((copy_from_dinode(dp, ip)) != 0) {
+		/* handle bad return by returning NULL for ip */
+		set_nlink(ip, 1);	/* Don't want iput() deleting it */
+		iput(ip);
+		/* release the page */
+		release_metapage(mp);
+		return (NULL);
+
+	}
+
+	ip->i_mapping->a_ops = &jfs_metapage_aops;
+	mapping_set_gfp_mask(ip->i_mapping, GFP_NOFS);
+
+	/* Allocations to metadata inodes should not affect quotas */
+	ip->i_flags |= S_NOQUOTA;
+
+	if ((inum == FILESYSTEM_I) && (JFS_IP(ip)->ipimap == sbi->ipaimap)) {
+		sbi->gengen = le32_to_cpu(dp->di_gengen);
+		sbi->inostamp = le32_to_cpu(dp->di_inostamp);
+	}
+
+	/* release the page */
+	release_metapage(mp);
+
+	inode_fake_hash(ip);
+
+	return (ip);
+}
+
+/*
+ * NAME:	diWriteSpecial()
+ *
+ * FUNCTION:	Write the special inode to disk
+ *
+ * PARAMETERS:
+ *	ip - special inode
+ *	secondary - 1 if secondary aggregate inode table
+ *
+ * RETURN VALUES: none
+ */
+
+void diWriteSpecial(struct inode *ip, int secondary)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+	uint address;
+	struct dinode *dp;
+	ino_t inum = ip->i_ino;
+	struct metapage *mp;
+
+	if (secondary)
+		address = addressPXD(&sbi->ait2) >> sbi->l2nbperpage;
+	else
+		address = AITBL_OFF >> L2PSIZE;
+
+	ASSERT(inum < INOSPEREXT);
+
+	address += inum >> 3;	/* 8 inodes per 4K page */
+
+	/* read the page of fixed disk inode (AIT) in raw mode */
+	mp = read_metapage(ip, address << sbi->l2nbperpage, PSIZE, 1);
+	if (mp == NULL) {
+		jfs_err("diWriteSpecial: failed to read aggregate inode extent!");
+		return;
+	}
+
+	/* get the pointer to the disk inode of interest */
+	dp = (struct dinode *) (mp->data);
+	dp += inum % 8;		/* 8 inodes per 4K page */
+
+	/* copy on-disk inode to in-memory inode */
+	copy_to_dinode(dp, ip);
+	memcpy(&dp->di_xtroot, &JFS_IP(ip)->i_xtroot, 288);
+
+	if (inum == FILESYSTEM_I)
+		dp->di_gengen = cpu_to_le32(sbi->gengen);
+
+	/* write the page */
+	write_metapage(mp);
+}
+
+/*
+ * NAME:	diFreeSpecial()
+ *
+ * FUNCTION:	Free allocated space for special inode
+ */
+void diFreeSpecial(struct inode *ip)
+{
+	if (ip == NULL) {
+		jfs_err("diFreeSpecial called with NULL ip!");
+		return;
+	}
+	filemap_write_and_wait(ip->i_mapping);
+	truncate_inode_pages(ip->i_mapping, 0);
+	iput(ip);
+}
+
+
+
+/*
+ * NAME:	diWrite()
+ *
+ * FUNCTION:	write the on-disk inode portion of the in-memory inode
+ *		to its corresponding on-disk inode.
+ *
+ *		on entry, the specifed incore inode should itself
+ *		specify the disk inode number corresponding to the
+ *		incore inode (i.e. i_number should be initialized).
+ *
+ *		the inode contains the inode extent address for the disk
+ *		inode.  with the inode extent address in hand, the
+ *		page of the extent that contains the disk inode is
+ *		read and the disk inode portion of the incore inode
+ *		is copied to the disk inode.
+ *
+ * PARAMETERS:
+ *	tid -  transacation id
+ *	ip  -  pointer to incore inode to be written to the inode extent.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error.
+ */
+int diWrite(tid_t tid, struct inode *ip)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	int rc = 0;
+	s32 ino;
+	struct dinode *dp;
+	s64 blkno;
+	int block_offset;
+	int inodes_left;
+	struct metapage *mp;
+	unsigned long pageno;
+	int rel_inode;
+	int dioffset;
+	struct inode *ipimap;
+	uint type;
+	lid_t lid;
+	struct tlock *ditlck, *tlck;
+	struct linelock *dilinelock, *ilinelock;
+	struct lv *lv;
+	int n;
+
+	ipimap = jfs_ip->ipimap;
+
+	ino = ip->i_ino & (INOSPERIAG - 1);
+
+	if (!addressPXD(&(jfs_ip->ixpxd)) ||
+	    (lengthPXD(&(jfs_ip->ixpxd)) !=
+	     JFS_IP(ipimap)->i_imap->im_nbperiext)) {
+		jfs_error(ip->i_sb, "ixpxd invalid\n");
+		return -EIO;
+	}
+
+	/*
+	 * read the page of disk inode containing the specified inode:
+	 */
+	/* compute the block address of the page */
+	blkno = INOPBLK(&(jfs_ip->ixpxd), ino, sbi->l2nbperpage);
+
+	rel_inode = (ino & (INOSPERPAGE - 1));
+	pageno = blkno >> sbi->l2nbperpage;
+
+	if ((block_offset = ((u32) blkno & (sbi->nbperpage - 1)))) {
+		/*
+		 * OS/2 didn't always align inode extents on page boundaries
+		 */
+		inodes_left =
+		    (sbi->nbperpage - block_offset) << sbi->l2niperblk;
+
+		if (rel_inode < inodes_left)
+			rel_inode += block_offset << sbi->l2niperblk;
+		else {
+			pageno += 1;
+			rel_inode -= inodes_left;
+		}
+	}
+	/* read the page of disk inode */
+      retry:
+	mp = read_metapage(ipimap, pageno << sbi->l2nbperpage, PSIZE, 1);
+	if (!mp)
+		return -EIO;
+
+	/* get the pointer to the disk inode */
+	dp = (struct dinode *) mp->data;
+	dp += rel_inode;
+
+	dioffset = (ino & (INOSPERPAGE - 1)) << L2DISIZE;
+
+	/*
+	 * acquire transaction lock on the on-disk inode;
+	 * N.B. tlock is acquired on ipimap not ip;
+	 */
+	if ((ditlck =
+	     txLock(tid, ipimap, mp, tlckINODE | tlckENTRY)) == NULL)
+		goto retry;
+	dilinelock = (struct linelock *) & ditlck->lock;
+
+	/*
+	 * copy btree root from in-memory inode to on-disk inode
+	 *
+	 * (tlock is taken from inline B+-tree root in in-memory
+	 * inode when the B+-tree root is updated, which is pointed
+	 * by jfs_ip->blid as well as being on tx tlock list)
+	 *
+	 * further processing of btree root is based on the copy
+	 * in in-memory inode, where txLog() will log from, and,
+	 * for xtree root, txUpdateMap() will update map and reset
+	 * XAD_NEW bit;
+	 */
+
+	if (S_ISDIR(ip->i_mode) && (lid = jfs_ip->xtlid)) {
+		/*
+		 * This is the special xtree inside the directory for storing
+		 * the directory table
+		 */
+		xtpage_t *p, *xp;
+		xad_t *xad;
+
+		jfs_ip->xtlid = 0;
+		tlck = lid_to_tlock(lid);
+		assert(tlck->type & tlckXTREE);
+		tlck->type |= tlckBTROOT;
+		tlck->mp = mp;
+		ilinelock = (struct linelock *) & tlck->lock;
+
+		/*
+		 * copy xtree root from inode to dinode:
+		 */
+		p = &jfs_ip->i_xtroot;
+		xp = (xtpage_t *) &dp->di_dirtable;
+		lv = ilinelock->lv;
+		for (n = 0; n < ilinelock->index; n++, lv++) {
+			memcpy(&xp->xad[lv->offset], &p->xad[lv->offset],
+			       lv->length << L2XTSLOTSIZE);
+		}
+
+		/* reset on-disk (metadata page) xtree XAD_NEW bit */
+		xad = &xp->xad[XTENTRYSTART];
+		for (n = XTENTRYSTART;
+		     n < le16_to_cpu(xp->header.nextindex); n++, xad++)
+			if (xad->flag & (XAD_NEW | XAD_EXTENDED))
+				xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
+	}
+
+	if ((lid = jfs_ip->blid) == 0)
+		goto inlineData;
+	jfs_ip->blid = 0;
+
+	tlck = lid_to_tlock(lid);
+	type = tlck->type;
+	tlck->type |= tlckBTROOT;
+	tlck->mp = mp;
+	ilinelock = (struct linelock *) & tlck->lock;
+
+	/*
+	 *	regular file: 16 byte (XAD slot) granularity
+	 */
+	if (type & tlckXTREE) {
+		xtpage_t *p, *xp;
+		xad_t *xad;
+
+		/*
+		 * copy xtree root from inode to dinode:
+		 */
+		p = &jfs_ip->i_xtroot;
+		xp = &dp->di_xtroot;
+		lv = ilinelock->lv;
+		for (n = 0; n < ilinelock->index; n++, lv++) {
+			memcpy(&xp->xad[lv->offset], &p->xad[lv->offset],
+			       lv->length << L2XTSLOTSIZE);
+		}
+
+		/* reset on-disk (metadata page) xtree XAD_NEW bit */
+		xad = &xp->xad[XTENTRYSTART];
+		for (n = XTENTRYSTART;
+		     n < le16_to_cpu(xp->header.nextindex); n++, xad++)
+			if (xad->flag & (XAD_NEW | XAD_EXTENDED))
+				xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
+	}
+	/*
+	 *	directory: 32 byte (directory entry slot) granularity
+	 */
+	else if (type & tlckDTREE) {
+		dtpage_t *p, *xp;
+
+		/*
+		 * copy dtree root from inode to dinode:
+		 */
+		p = (dtpage_t *) &jfs_ip->i_dtroot;
+		xp = (dtpage_t *) & dp->di_dtroot;
+		lv = ilinelock->lv;
+		for (n = 0; n < ilinelock->index; n++, lv++) {
+			memcpy(&xp->slot[lv->offset], &p->slot[lv->offset],
+			       lv->length << L2DTSLOTSIZE);
+		}
+	} else {
+		jfs_err("diWrite: UFO tlock");
+	}
+
+      inlineData:
+	/*
+	 * copy inline symlink from in-memory inode to on-disk inode
+	 */
+	if (S_ISLNK(ip->i_mode) && ip->i_size < IDATASIZE) {
+		lv = & dilinelock->lv[dilinelock->index];
+		lv->offset = (dioffset + 2 * 128) >> L2INODESLOTSIZE;
+		lv->length = 2;
+		memcpy(&dp->di_inline_all, jfs_ip->i_inline_all, IDATASIZE);
+		dilinelock->index++;
+	}
+	/*
+	 * copy inline data from in-memory inode to on-disk inode:
+	 * 128 byte slot granularity
+	 */
+	if (test_cflag(COMMIT_Inlineea, ip)) {
+		lv = & dilinelock->lv[dilinelock->index];
+		lv->offset = (dioffset + 3 * 128) >> L2INODESLOTSIZE;
+		lv->length = 1;
+		memcpy(&dp->di_inlineea, jfs_ip->i_inline_ea, INODESLOTSIZE);
+		dilinelock->index++;
+
+		clear_cflag(COMMIT_Inlineea, ip);
+	}
+
+	/*
+	 *	lock/copy inode base: 128 byte slot granularity
+	 */
+	lv = & dilinelock->lv[dilinelock->index];
+	lv->offset = dioffset >> L2INODESLOTSIZE;
+	copy_to_dinode(dp, ip);
+	if (test_and_clear_cflag(COMMIT_Dirtable, ip)) {
+		lv->length = 2;
+		memcpy(&dp->di_dirtable, &jfs_ip->i_dirtable, 96);
+	} else
+		lv->length = 1;
+	dilinelock->index++;
+
+	/* release the buffer holding the updated on-disk inode.
+	 * the buffer will be later written by commit processing.
+	 */
+	write_metapage(mp);
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	diFree(ip)
+ *
+ * FUNCTION:	free a specified inode from the inode working map
+ *		for a fileset or aggregate.
+ *
+ *		if the inode to be freed represents the first (only)
+ *		free inode within the iag, the iag will be placed on
+ *		the ag free inode list.
+ *
+ *		freeing the inode will cause the inode extent to be
+ *		freed if the inode is the only allocated inode within
+ *		the extent.  in this case all the disk resource backing
+ *		up the inode extent will be freed. in addition, the iag
+ *		will be placed on the ag extent free list if the extent
+ *		is the first free extent in the iag.  if freeing the
+ *		extent also means that no free inodes will exist for
+ *		the iag, the iag will also be removed from the ag free
+ *		inode list.
+ *
+ *		the iag describing the inode will be freed if the extent
+ *		is to be freed and it is the only backed extent within
+ *		the iag.  in this case, the iag will be removed from the
+ *		ag free extent list and ag free inode list and placed on
+ *		the inode map's free iag list.
+ *
+ *		a careful update approach is used to provide consistency
+ *		in the face of updates to multiple buffers.  under this
+ *		approach, all required buffers are obtained before making
+ *		any updates and are held until all updates are complete.
+ *
+ * PARAMETERS:
+ *	ip	- inode to be freed.
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-EIO	- i/o error.
+ */
+int diFree(struct inode *ip)
+{
+	int rc;
+	ino_t inum = ip->i_ino;
+	struct iag *iagp, *aiagp, *biagp, *ciagp, *diagp;
+	struct metapage *mp, *amp, *bmp, *cmp, *dmp;
+	int iagno, ino, extno, bitno, sword, agno;
+	int back, fwd;
+	u32 bitmap, mask;
+	struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap;
+	struct inomap *imap = JFS_IP(ipimap)->i_imap;
+	pxd_t freepxd;
+	tid_t tid;
+	struct inode *iplist[3];
+	struct tlock *tlck;
+	struct pxd_lock *pxdlock;
+
+	/*
+	 * This is just to suppress compiler warnings.  The same logic that
+	 * references these variables is used to initialize them.
+	 */
+	aiagp = biagp = ciagp = diagp = NULL;
+
+	/* get the iag number containing the inode.
+	 */
+	iagno = INOTOIAG(inum);
+
+	/* make sure that the iag is contained within
+	 * the map.
+	 */
+	if (iagno >= imap->im_nextiag) {
+		print_hex_dump(KERN_ERR, "imap: ", DUMP_PREFIX_ADDRESS, 16, 4,
+			       imap, 32, 0);
+		jfs_error(ip->i_sb, "inum = %d, iagno = %d, nextiag = %d\n",
+			  (uint) inum, iagno, imap->im_nextiag);
+		return -EIO;
+	}
+
+	/* get the allocation group for this ino.
+	 */
+	agno = BLKTOAG(JFS_IP(ip)->agstart, JFS_SBI(ip->i_sb));
+
+	/* Lock the AG specific inode map information
+	 */
+	AG_LOCK(imap, agno);
+
+	/* Obtain read lock in imap inode.  Don't release it until we have
+	 * read all of the IAG's that we are going to.
+	 */
+	IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
+
+	/* read the iag.
+	 */
+	if ((rc = diIAGRead(imap, iagno, &mp))) {
+		IREAD_UNLOCK(ipimap);
+		AG_UNLOCK(imap, agno);
+		return (rc);
+	}
+	iagp = (struct iag *) mp->data;
+
+	/* get the inode number and extent number of the inode within
+	 * the iag and the inode number within the extent.
+	 */
+	ino = inum & (INOSPERIAG - 1);
+	extno = ino >> L2INOSPEREXT;
+	bitno = ino & (INOSPEREXT - 1);
+	mask = HIGHORDER >> bitno;
+
+	if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
+		jfs_error(ip->i_sb, "wmap shows inode already free\n");
+	}
+
+	if (!addressPXD(&iagp->inoext[extno])) {
+		release_metapage(mp);
+		IREAD_UNLOCK(ipimap);
+		AG_UNLOCK(imap, agno);
+		jfs_error(ip->i_sb, "invalid inoext\n");
+		return -EIO;
+	}
+
+	/* compute the bitmap for the extent reflecting the freed inode.
+	 */
+	bitmap = le32_to_cpu(iagp->wmap[extno]) & ~mask;
+
+	if (imap->im_agctl[agno].numfree > imap->im_agctl[agno].numinos) {
+		release_metapage(mp);
+		IREAD_UNLOCK(ipimap);
+		AG_UNLOCK(imap, agno);
+		jfs_error(ip->i_sb, "numfree > numinos\n");
+		return -EIO;
+	}
+	/*
+	 *	inode extent still has some inodes or below low water mark:
+	 *	keep the inode extent;
+	 */
+	if (bitmap ||
+	    imap->im_agctl[agno].numfree < 96 ||
+	    (imap->im_agctl[agno].numfree < 288 &&
+	     (((imap->im_agctl[agno].numfree * 100) /
+	       imap->im_agctl[agno].numinos) <= 25))) {
+		/* if the iag currently has no free inodes (i.e.,
+		 * the inode being freed is the first free inode of iag),
+		 * insert the iag at head of the inode free list for the ag.
+		 */
+		if (iagp->nfreeinos == 0) {
+			/* check if there are any iags on the ag inode
+			 * free list.  if so, read the first one so that
+			 * we can link the current iag onto the list at
+			 * the head.
+			 */
+			if ((fwd = imap->im_agctl[agno].inofree) >= 0) {
+				/* read the iag that currently is the head
+				 * of the list.
+				 */
+				if ((rc = diIAGRead(imap, fwd, &amp))) {
+					IREAD_UNLOCK(ipimap);
+					AG_UNLOCK(imap, agno);
+					release_metapage(mp);
+					return (rc);
+				}
+				aiagp = (struct iag *) amp->data;
+
+				/* make current head point back to the iag.
+				 */
+				aiagp->inofreeback = cpu_to_le32(iagno);
+
+				write_metapage(amp);
+			}
+
+			/* iag points forward to current head and iag
+			 * becomes the new head of the list.
+			 */
+			iagp->inofreefwd =
+			    cpu_to_le32(imap->im_agctl[agno].inofree);
+			iagp->inofreeback = cpu_to_le32(-1);
+			imap->im_agctl[agno].inofree = iagno;
+		}
+		IREAD_UNLOCK(ipimap);
+
+		/* update the free inode summary map for the extent if
+		 * freeing the inode means the extent will now have free
+		 * inodes (i.e., the inode being freed is the first free
+		 * inode of extent),
+		 */
+		if (iagp->wmap[extno] == cpu_to_le32(ONES)) {
+			sword = extno >> L2EXTSPERSUM;
+			bitno = extno & (EXTSPERSUM - 1);
+			iagp->inosmap[sword] &=
+			    cpu_to_le32(~(HIGHORDER >> bitno));
+		}
+
+		/* update the bitmap.
+		 */
+		iagp->wmap[extno] = cpu_to_le32(bitmap);
+
+		/* update the free inode counts at the iag, ag and
+		 * map level.
+		 */
+		le32_add_cpu(&iagp->nfreeinos, 1);
+		imap->im_agctl[agno].numfree += 1;
+		atomic_inc(&imap->im_numfree);
+
+		/* release the AG inode map lock
+		 */
+		AG_UNLOCK(imap, agno);
+
+		/* write the iag */
+		write_metapage(mp);
+
+		return (0);
+	}
+
+
+	/*
+	 *	inode extent has become free and above low water mark:
+	 *	free the inode extent;
+	 */
+
+	/*
+	 *	prepare to update iag list(s) (careful update step 1)
+	 */
+	amp = bmp = cmp = dmp = NULL;
+	fwd = back = -1;
+
+	/* check if the iag currently has no free extents.  if so,
+	 * it will be placed on the head of the ag extent free list.
+	 */
+	if (iagp->nfreeexts == 0) {
+		/* check if the ag extent free list has any iags.
+		 * if so, read the iag at the head of the list now.
+		 * this (head) iag will be updated later to reflect
+		 * the addition of the current iag at the head of
+		 * the list.
+		 */
+		if ((fwd = imap->im_agctl[agno].extfree) >= 0) {
+			if ((rc = diIAGRead(imap, fwd, &amp)))
+				goto error_out;
+			aiagp = (struct iag *) amp->data;
+		}
+	} else {
+		/* iag has free extents. check if the addition of a free
+		 * extent will cause all extents to be free within this
+		 * iag.  if so, the iag will be removed from the ag extent
+		 * free list and placed on the inode map's free iag list.
+		 */
+		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG - 1)) {
+			/* in preparation for removing the iag from the
+			 * ag extent free list, read the iags preceding
+			 * and following the iag on the ag extent free
+			 * list.
+			 */
+			if ((fwd = le32_to_cpu(iagp->extfreefwd)) >= 0) {
+				if ((rc = diIAGRead(imap, fwd, &amp)))
+					goto error_out;
+				aiagp = (struct iag *) amp->data;
+			}
+
+			if ((back = le32_to_cpu(iagp->extfreeback)) >= 0) {
+				if ((rc = diIAGRead(imap, back, &bmp)))
+					goto error_out;
+				biagp = (struct iag *) bmp->data;
+			}
+		}
+	}
+
+	/* remove the iag from the ag inode free list if freeing
+	 * this extent cause the iag to have no free inodes.
+	 */
+	if (iagp->nfreeinos == cpu_to_le32(INOSPEREXT - 1)) {
+		int inofreeback = le32_to_cpu(iagp->inofreeback);
+		int inofreefwd = le32_to_cpu(iagp->inofreefwd);
+
+		/* in preparation for removing the iag from the
+		 * ag inode free list, read the iags preceding
+		 * and following the iag on the ag inode free
+		 * list.  before reading these iags, we must make
+		 * sure that we already don't have them in hand
+		 * from up above, since re-reading an iag (buffer)
+		 * we are currently holding would cause a deadlock.
+		 */
+		if (inofreefwd >= 0) {
+
+			if (inofreefwd == fwd)
+				ciagp = (struct iag *) amp->data;
+			else if (inofreefwd == back)
+				ciagp = (struct iag *) bmp->data;
+			else {
+				if ((rc =
+				     diIAGRead(imap, inofreefwd, &cmp)))
+					goto error_out;
+				ciagp = (struct iag *) cmp->data;
+			}
+			assert(ciagp != NULL);
+		}
+
+		if (inofreeback >= 0) {
+			if (inofreeback == fwd)
+				diagp = (struct iag *) amp->data;
+			else if (inofreeback == back)
+				diagp = (struct iag *) bmp->data;
+			else {
+				if ((rc =
+				     diIAGRead(imap, inofreeback, &dmp)))
+					goto error_out;
+				diagp = (struct iag *) dmp->data;
+			}
+			assert(diagp != NULL);
+		}
+	}
+
+	IREAD_UNLOCK(ipimap);
+
+	/*
+	 * invalidate any page of the inode extent freed from buffer cache;
+	 */
+	freepxd = iagp->inoext[extno];
+	invalidate_pxd_metapages(ip, freepxd);
+
+	/*
+	 *	update iag list(s) (careful update step 2)
+	 */
+	/* add the iag to the ag extent free list if this is the
+	 * first free extent for the iag.
+	 */
+	if (iagp->nfreeexts == 0) {
+		if (fwd >= 0)
+			aiagp->extfreeback = cpu_to_le32(iagno);
+
+		iagp->extfreefwd =
+		    cpu_to_le32(imap->im_agctl[agno].extfree);
+		iagp->extfreeback = cpu_to_le32(-1);
+		imap->im_agctl[agno].extfree = iagno;
+	} else {
+		/* remove the iag from the ag extent list if all extents
+		 * are now free and place it on the inode map iag free list.
+		 */
+		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG - 1)) {
+			if (fwd >= 0)
+				aiagp->extfreeback = iagp->extfreeback;
+
+			if (back >= 0)
+				biagp->extfreefwd = iagp->extfreefwd;
+			else
+				imap->im_agctl[agno].extfree =
+				    le32_to_cpu(iagp->extfreefwd);
+
+			iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
+
+			IAGFREE_LOCK(imap);
+			iagp->iagfree = cpu_to_le32(imap->im_freeiag);
+			imap->im_freeiag = iagno;
+			IAGFREE_UNLOCK(imap);
+		}
+	}
+
+	/* remove the iag from the ag inode free list if freeing
+	 * this extent causes the iag to have no free inodes.
+	 */
+	if (iagp->nfreeinos == cpu_to_le32(INOSPEREXT - 1)) {
+		if ((int) le32_to_cpu(iagp->inofreefwd) >= 0)
+			ciagp->inofreeback = iagp->inofreeback;
+
+		if ((int) le32_to_cpu(iagp->inofreeback) >= 0)
+			diagp->inofreefwd = iagp->inofreefwd;
+		else
+			imap->im_agctl[agno].inofree =
+			    le32_to_cpu(iagp->inofreefwd);
+
+		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
+	}
+
+	/* update the inode extent address and working map
+	 * to reflect the free extent.
+	 * the permanent map should have been updated already
+	 * for the inode being freed.
+	 */
+	if (iagp->pmap[extno] != 0) {
+		jfs_error(ip->i_sb, "the pmap does not show inode free\n");
+	}
+	iagp->wmap[extno] = 0;
+	PXDlength(&iagp->inoext[extno], 0);
+	PXDaddress(&iagp->inoext[extno], 0);
+
+	/* update the free extent and free inode summary maps
+	 * to reflect the freed extent.
+	 * the inode summary map is marked to indicate no inodes
+	 * available for the freed extent.
+	 */
+	sword = extno >> L2EXTSPERSUM;
+	bitno = extno & (EXTSPERSUM - 1);
+	mask = HIGHORDER >> bitno;
+	iagp->inosmap[sword] |= cpu_to_le32(mask);
+	iagp->extsmap[sword] &= cpu_to_le32(~mask);
+
+	/* update the number of free inodes and number of free extents
+	 * for the iag.
+	 */
+	le32_add_cpu(&iagp->nfreeinos, -(INOSPEREXT - 1));
+	le32_add_cpu(&iagp->nfreeexts, 1);
+
+	/* update the number of free inodes and backed inodes
+	 * at the ag and inode map level.
+	 */
+	imap->im_agctl[agno].numfree -= (INOSPEREXT - 1);
+	imap->im_agctl[agno].numinos -= INOSPEREXT;
+	atomic_sub(INOSPEREXT - 1, &imap->im_numfree);
+	atomic_sub(INOSPEREXT, &imap->im_numinos);
+
+	if (amp)
+		write_metapage(amp);
+	if (bmp)
+		write_metapage(bmp);
+	if (cmp)
+		write_metapage(cmp);
+	if (dmp)
+		write_metapage(dmp);
+
+	/*
+	 * start transaction to update block allocation map
+	 * for the inode extent freed;
+	 *
+	 * N.B. AG_LOCK is released and iag will be released below, and
+	 * other thread may allocate inode from/reusing the ixad freed
+	 * BUT with new/different backing inode extent from the extent
+	 * to be freed by the transaction;
+	 */
+	tid = txBegin(ipimap->i_sb, COMMIT_FORCE);
+	mutex_lock(&JFS_IP(ipimap)->commit_mutex);
+
+	/* acquire tlock of the iag page of the freed ixad
+	 * to force the page NOHOMEOK (even though no data is
+	 * logged from the iag page) until NOREDOPAGE|FREEXTENT log
+	 * for the free of the extent is committed;
+	 * write FREEXTENT|NOREDOPAGE log record
+	 * N.B. linelock is overlaid as freed extent descriptor;
+	 */
+	tlck = txLock(tid, ipimap, mp, tlckINODE | tlckFREE);
+	pxdlock = (struct pxd_lock *) & tlck->lock;
+	pxdlock->flag = mlckFREEPXD;
+	pxdlock->pxd = freepxd;
+	pxdlock->index = 1;
+
+	write_metapage(mp);
+
+	iplist[0] = ipimap;
+
+	/*
+	 * logredo needs the IAG number and IAG extent index in order
+	 * to ensure that the IMap is consistent.  The least disruptive
+	 * way to pass these values through  to the transaction manager
+	 * is in the iplist array.
+	 *
+	 * It's not pretty, but it works.
+	 */
+	iplist[1] = (struct inode *) (size_t)iagno;
+	iplist[2] = (struct inode *) (size_t)extno;
+
+	rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
+
+	txEnd(tid);
+	mutex_unlock(&JFS_IP(ipimap)->commit_mutex);
+
+	/* unlock the AG inode map information */
+	AG_UNLOCK(imap, agno);
+
+	return (0);
+
+      error_out:
+	IREAD_UNLOCK(ipimap);
+
+	if (amp)
+		release_metapage(amp);
+	if (bmp)
+		release_metapage(bmp);
+	if (cmp)
+		release_metapage(cmp);
+	if (dmp)
+		release_metapage(dmp);
+
+	AG_UNLOCK(imap, agno);
+
+	release_metapage(mp);
+
+	return (rc);
+}
+
+/*
+ * There are several places in the diAlloc* routines where we initialize
+ * the inode.
+ */
+static inline void
+diInitInode(struct inode *ip, int iagno, int ino, int extno, struct iag * iagp)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+
+	ip->i_ino = (iagno << L2INOSPERIAG) + ino;
+	jfs_ip->ixpxd = iagp->inoext[extno];
+	jfs_ip->agstart = le64_to_cpu(iagp->agstart);
+	jfs_ip->active_ag = -1;
+}
+
+
+/*
+ * NAME:	diAlloc(pip,dir,ip)
+ *
+ * FUNCTION:	allocate a disk inode from the inode working map
+ *		for a fileset or aggregate.
+ *
+ * PARAMETERS:
+ *	pip	- pointer to incore inode for the parent inode.
+ *	dir	- 'true' if the new disk inode is for a directory.
+ *	ip	- pointer to a new inode
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-ENOSPC	- insufficient disk resources.
+ *	-EIO	- i/o error.
+ */
+int diAlloc(struct inode *pip, bool dir, struct inode *ip)
+{
+	int rc, ino, iagno, addext, extno, bitno, sword;
+	int nwords, rem, i, agno, dn_numag;
+	u32 mask, inosmap, extsmap;
+	struct inode *ipimap;
+	struct metapage *mp;
+	ino_t inum;
+	struct iag *iagp;
+	struct inomap *imap;
+
+	/* get the pointers to the inode map inode and the
+	 * corresponding imap control structure.
+	 */
+	ipimap = JFS_SBI(pip->i_sb)->ipimap;
+	imap = JFS_IP(ipimap)->i_imap;
+	JFS_IP(ip)->ipimap = ipimap;
+	JFS_IP(ip)->fileset = FILESYSTEM_I;
+
+	/* for a directory, the allocation policy is to start
+	 * at the ag level using the preferred ag.
+	 */
+	if (dir) {
+		agno = dbNextAG(JFS_SBI(pip->i_sb)->ipbmap);
+		AG_LOCK(imap, agno);
+		goto tryag;
+	}
+
+	/* for files, the policy starts off by trying to allocate from
+	 * the same iag containing the parent disk inode:
+	 * try to allocate the new disk inode close to the parent disk
+	 * inode, using parent disk inode number + 1 as the allocation
+	 * hint.  (we use a left-to-right policy to attempt to avoid
+	 * moving backward on the disk.)  compute the hint within the
+	 * file system and the iag.
+	 */
+
+	/* get the ag number of this iag */
+	agno = BLKTOAG(JFS_IP(pip)->agstart, JFS_SBI(pip->i_sb));
+	dn_numag = JFS_SBI(pip->i_sb)->bmap->db_numag;
+	if (agno < 0 || agno > dn_numag)
+		return -EIO;
+
+	if (atomic_read(&JFS_SBI(pip->i_sb)->bmap->db_active[agno])) {
+		/*
+		 * There is an open file actively growing.  We want to
+		 * allocate new inodes from a different ag to avoid
+		 * fragmentation problems.
+		 */
+		agno = dbNextAG(JFS_SBI(pip->i_sb)->ipbmap);
+		AG_LOCK(imap, agno);
+		goto tryag;
+	}
+
+	inum = pip->i_ino + 1;
+	ino = inum & (INOSPERIAG - 1);
+
+	/* back off the hint if it is outside of the iag */
+	if (ino == 0)
+		inum = pip->i_ino;
+
+	/* lock the AG inode map information */
+	AG_LOCK(imap, agno);
+
+	/* Get read lock on imap inode */
+	IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
+
+	/* get the iag number and read the iag */
+	iagno = INOTOIAG(inum);
+	if ((rc = diIAGRead(imap, iagno, &mp))) {
+		IREAD_UNLOCK(ipimap);
+		AG_UNLOCK(imap, agno);
+		return (rc);
+	}
+	iagp = (struct iag *) mp->data;
+
+	/* determine if new inode extent is allowed to be added to the iag.
+	 * new inode extent can be added to the iag if the ag
+	 * has less than 32 free disk inodes and the iag has free extents.
+	 */
+	addext = (imap->im_agctl[agno].numfree < 32 && iagp->nfreeexts);
+
+	/*
+	 *	try to allocate from the IAG
+	 */
+	/* check if the inode may be allocated from the iag
+	 * (i.e. the inode has free inodes or new extent can be added).
+	 */
+	if (iagp->nfreeinos || addext) {
+		/* determine the extent number of the hint.
+		 */
+		extno = ino >> L2INOSPEREXT;
+
+		/* check if the extent containing the hint has backed
+		 * inodes.  if so, try to allocate within this extent.
+		 */
+		if (addressPXD(&iagp->inoext[extno])) {
+			bitno = ino & (INOSPEREXT - 1);
+			if ((bitno =
+			     diFindFree(le32_to_cpu(iagp->wmap[extno]),
+					bitno))
+			    < INOSPEREXT) {
+				ino = (extno << L2INOSPEREXT) + bitno;
+
+				/* a free inode (bit) was found within this
+				 * extent, so allocate it.
+				 */
+				rc = diAllocBit(imap, iagp, ino);
+				IREAD_UNLOCK(ipimap);
+				if (rc) {
+					assert(rc == -EIO);
+				} else {
+					/* set the results of the allocation
+					 * and write the iag.
+					 */
+					diInitInode(ip, iagno, ino, extno,
+						    iagp);
+					mark_metapage_dirty(mp);
+				}
+				release_metapage(mp);
+
+				/* free the AG lock and return.
+				 */
+				AG_UNLOCK(imap, agno);
+				return (rc);
+			}
+
+			if (!addext)
+				extno =
+				    (extno ==
+				     EXTSPERIAG - 1) ? 0 : extno + 1;
+		}
+
+		/*
+		 * no free inodes within the extent containing the hint.
+		 *
+		 * try to allocate from the backed extents following
+		 * hint or, if appropriate (i.e. addext is true), allocate
+		 * an extent of free inodes at or following the extent
+		 * containing the hint.
+		 *
+		 * the free inode and free extent summary maps are used
+		 * here, so determine the starting summary map position
+		 * and the number of words we'll have to examine.  again,
+		 * the approach is to allocate following the hint, so we
+		 * might have to initially ignore prior bits of the summary
+		 * map that represent extents prior to the extent containing
+		 * the hint and later revisit these bits.
+		 */
+		bitno = extno & (EXTSPERSUM - 1);
+		nwords = (bitno == 0) ? SMAPSZ : SMAPSZ + 1;
+		sword = extno >> L2EXTSPERSUM;
+
+		/* mask any prior bits for the starting words of the
+		 * summary map.
+		 */
+		mask = (bitno == 0) ? 0 : (ONES << (EXTSPERSUM - bitno));
+		inosmap = le32_to_cpu(iagp->inosmap[sword]) | mask;
+		extsmap = le32_to_cpu(iagp->extsmap[sword]) | mask;
+
+		/* scan the free inode and free extent summary maps for
+		 * free resources.
+		 */
+		for (i = 0; i < nwords; i++) {
+			/* check if this word of the free inode summary
+			 * map describes an extent with free inodes.
+			 */
+			if (~inosmap) {
+				/* an extent with free inodes has been
+				 * found. determine the extent number
+				 * and the inode number within the extent.
+				 */
+				rem = diFindFree(inosmap, 0);
+				extno = (sword << L2EXTSPERSUM) + rem;
+				rem = diFindFree(le32_to_cpu(iagp->wmap[extno]),
+						 0);
+				if (rem >= INOSPEREXT) {
+					IREAD_UNLOCK(ipimap);
+					release_metapage(mp);
+					AG_UNLOCK(imap, agno);
+					jfs_error(ip->i_sb,
+						  "can't find free bit in wmap\n");
+					return -EIO;
+				}
+
+				/* determine the inode number within the
+				 * iag and allocate the inode from the
+				 * map.
+				 */
+				ino = (extno << L2INOSPEREXT) + rem;
+				rc = diAllocBit(imap, iagp, ino);
+				IREAD_UNLOCK(ipimap);
+				if (rc)
+					assert(rc == -EIO);
+				else {
+					/* set the results of the allocation
+					 * and write the iag.
+					 */
+					diInitInode(ip, iagno, ino, extno,
+						    iagp);
+					mark_metapage_dirty(mp);
+				}
+				release_metapage(mp);
+
+				/* free the AG lock and return.
+				 */
+				AG_UNLOCK(imap, agno);
+				return (rc);
+
+			}
+
+			/* check if we may allocate an extent of free
+			 * inodes and whether this word of the free
+			 * extents summary map describes a free extent.
+			 */
+			if (addext && ~extsmap) {
+				/* a free extent has been found.  determine
+				 * the extent number.
+				 */
+				rem = diFindFree(extsmap, 0);
+				extno = (sword << L2EXTSPERSUM) + rem;
+
+				/* allocate an extent of free inodes.
+				 */
+				if ((rc = diNewExt(imap, iagp, extno))) {
+					/* if there is no disk space for a
+					 * new extent, try to allocate the
+					 * disk inode from somewhere else.
+					 */
+					if (rc == -ENOSPC)
+						break;
+
+					assert(rc == -EIO);
+				} else {
+					/* set the results of the allocation
+					 * and write the iag.
+					 */
+					diInitInode(ip, iagno,
+						    extno << L2INOSPEREXT,
+						    extno, iagp);
+					mark_metapage_dirty(mp);
+				}
+				release_metapage(mp);
+				/* free the imap inode & the AG lock & return.
+				 */
+				IREAD_UNLOCK(ipimap);
+				AG_UNLOCK(imap, agno);
+				return (rc);
+			}
+
+			/* move on to the next set of summary map words.
+			 */
+			sword = (sword == SMAPSZ - 1) ? 0 : sword + 1;
+			inosmap = le32_to_cpu(iagp->inosmap[sword]);
+			extsmap = le32_to_cpu(iagp->extsmap[sword]);
+		}
+	}
+	/* unlock imap inode */
+	IREAD_UNLOCK(ipimap);
+
+	/* nothing doing in this iag, so release it. */
+	release_metapage(mp);
+
+      tryag:
+	/*
+	 * try to allocate anywhere within the same AG as the parent inode.
+	 */
+	rc = diAllocAG(imap, agno, dir, ip);
+
+	AG_UNLOCK(imap, agno);
+
+	if (rc != -ENOSPC)
+		return (rc);
+
+	/*
+	 * try to allocate in any AG.
+	 */
+	return (diAllocAny(imap, agno, dir, ip));
+}
+
+
+/*
+ * NAME:	diAllocAG(imap,agno,dir,ip)
+ *
+ * FUNCTION:	allocate a disk inode from the allocation group.
+ *
+ *		this routine first determines if a new extent of free
+ *		inodes should be added for the allocation group, with
+ *		the current request satisfied from this extent. if this
+ *		is the case, an attempt will be made to do just that.  if
+ *		this attempt fails or it has been determined that a new
+ *		extent should not be added, an attempt is made to satisfy
+ *		the request by allocating an existing (backed) free inode
+ *		from the allocation group.
+ *
+ * PRE CONDITION: Already have the AG lock for this AG.
+ *
+ * PARAMETERS:
+ *	imap	- pointer to inode map control structure.
+ *	agno	- allocation group to allocate from.
+ *	dir	- 'true' if the new disk inode is for a directory.
+ *	ip	- pointer to the new inode to be filled in on successful return
+ *		  with the disk inode number allocated, its extent address
+ *		  and the start of the ag.
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-ENOSPC	- insufficient disk resources.
+ *	-EIO	- i/o error.
+ */
+static int
+diAllocAG(struct inomap * imap, int agno, bool dir, struct inode *ip)
+{
+	int rc, addext, numfree, numinos;
+
+	/* get the number of free and the number of backed disk
+	 * inodes currently within the ag.
+	 */
+	numfree = imap->im_agctl[agno].numfree;
+	numinos = imap->im_agctl[agno].numinos;
+
+	if (numfree > numinos) {
+		jfs_error(ip->i_sb, "numfree > numinos\n");
+		return -EIO;
+	}
+
+	/* determine if we should allocate a new extent of free inodes
+	 * within the ag: for directory inodes, add a new extent
+	 * if there are a small number of free inodes or number of free
+	 * inodes is a small percentage of the number of backed inodes.
+	 */
+	if (dir)
+		addext = (numfree < 64 ||
+			  (numfree < 256
+			   && ((numfree * 100) / numinos) <= 20));
+	else
+		addext = (numfree == 0);
+
+	/*
+	 * try to allocate a new extent of free inodes.
+	 */
+	if (addext) {
+		/* if free space is not available for this new extent, try
+		 * below to allocate a free and existing (already backed)
+		 * inode from the ag.
+		 */
+		if ((rc = diAllocExt(imap, agno, ip)) != -ENOSPC)
+			return (rc);
+	}
+
+	/*
+	 * try to allocate an existing free inode from the ag.
+	 */
+	return (diAllocIno(imap, agno, ip));
+}
+
+
+/*
+ * NAME:	diAllocAny(imap,agno,dir,iap)
+ *
+ * FUNCTION:	allocate a disk inode from any other allocation group.
+ *
+ *		this routine is called when an allocation attempt within
+ *		the primary allocation group has failed. if attempts to
+ *		allocate an inode from any allocation group other than the
+ *		specified primary group.
+ *
+ * PARAMETERS:
+ *	imap	- pointer to inode map control structure.
+ *	agno	- primary allocation group (to avoid).
+ *	dir	- 'true' if the new disk inode is for a directory.
+ *	ip	- pointer to a new inode to be filled in on successful return
+ *		  with the disk inode number allocated, its extent address
+ *		  and the start of the ag.
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-ENOSPC	- insufficient disk resources.
+ *	-EIO	- i/o error.
+ */
+static int
+diAllocAny(struct inomap * imap, int agno, bool dir, struct inode *ip)
+{
+	int ag, rc;
+	int maxag = JFS_SBI(imap->im_ipimap->i_sb)->bmap->db_maxag;
+
+
+	/* try to allocate from the ags following agno up to
+	 * the maximum ag number.
+	 */
+	for (ag = agno + 1; ag <= maxag; ag++) {
+		AG_LOCK(imap, ag);
+
+		rc = diAllocAG(imap, ag, dir, ip);
+
+		AG_UNLOCK(imap, ag);
+
+		if (rc != -ENOSPC)
+			return (rc);
+	}
+
+	/* try to allocate from the ags in front of agno.
+	 */
+	for (ag = 0; ag < agno; ag++) {
+		AG_LOCK(imap, ag);
+
+		rc = diAllocAG(imap, ag, dir, ip);
+
+		AG_UNLOCK(imap, ag);
+
+		if (rc != -ENOSPC)
+			return (rc);
+	}
+
+	/* no free disk inodes.
+	 */
+	return -ENOSPC;
+}
+
+
+/*
+ * NAME:	diAllocIno(imap,agno,ip)
+ *
+ * FUNCTION:	allocate a disk inode from the allocation group's free
+ *		inode list, returning an error if this free list is
+ *		empty (i.e. no iags on the list).
+ *
+ *		allocation occurs from the first iag on the list using
+ *		the iag's free inode summary map to find the leftmost
+ *		free inode in the iag.
+ *
+ * PRE CONDITION: Already have AG lock for this AG.
+ *
+ * PARAMETERS:
+ *	imap	- pointer to inode map control structure.
+ *	agno	- allocation group.
+ *	ip	- pointer to new inode to be filled in on successful return
+ *		  with the disk inode number allocated, its extent address
+ *		  and the start of the ag.
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-ENOSPC	- insufficient disk resources.
+ *	-EIO	- i/o error.
+ */
+static int diAllocIno(struct inomap * imap, int agno, struct inode *ip)
+{
+	int iagno, ino, rc, rem, extno, sword;
+	struct metapage *mp;
+	struct iag *iagp;
+
+	/* check if there are iags on the ag's free inode list.
+	 */
+	if ((iagno = imap->im_agctl[agno].inofree) < 0)
+		return -ENOSPC;
+
+	/* obtain read lock on imap inode */
+	IREAD_LOCK(imap->im_ipimap, RDWRLOCK_IMAP);
+
+	/* read the iag at the head of the list.
+	 */
+	if ((rc = diIAGRead(imap, iagno, &mp))) {
+		IREAD_UNLOCK(imap->im_ipimap);
+		return (rc);
+	}
+	iagp = (struct iag *) mp->data;
+
+	/* better be free inodes in this iag if it is on the
+	 * list.
+	 */
+	if (!iagp->nfreeinos) {
+		IREAD_UNLOCK(imap->im_ipimap);
+		release_metapage(mp);
+		jfs_error(ip->i_sb, "nfreeinos = 0, but iag on freelist\n");
+		return -EIO;
+	}
+
+	/* scan the free inode summary map to find an extent
+	 * with free inodes.
+	 */
+	for (sword = 0;; sword++) {
+		if (sword >= SMAPSZ) {
+			IREAD_UNLOCK(imap->im_ipimap);
+			release_metapage(mp);
+			jfs_error(ip->i_sb,
+				  "free inode not found in summary map\n");
+			return -EIO;
+		}
+
+		if (~iagp->inosmap[sword])
+			break;
+	}
+
+	/* found a extent with free inodes. determine
+	 * the extent number.
+	 */
+	rem = diFindFree(le32_to_cpu(iagp->inosmap[sword]), 0);
+	if (rem >= EXTSPERSUM) {
+		IREAD_UNLOCK(imap->im_ipimap);
+		release_metapage(mp);
+		jfs_error(ip->i_sb, "no free extent found\n");
+		return -EIO;
+	}
+	extno = (sword << L2EXTSPERSUM) + rem;
+
+	/* find the first free inode in the extent.
+	 */
+	rem = diFindFree(le32_to_cpu(iagp->wmap[extno]), 0);
+	if (rem >= INOSPEREXT) {
+		IREAD_UNLOCK(imap->im_ipimap);
+		release_metapage(mp);
+		jfs_error(ip->i_sb, "free inode not found\n");
+		return -EIO;
+	}
+
+	/* compute the inode number within the iag.
+	 */
+	ino = (extno << L2INOSPEREXT) + rem;
+
+	/* allocate the inode.
+	 */
+	rc = diAllocBit(imap, iagp, ino);
+	IREAD_UNLOCK(imap->im_ipimap);
+	if (rc) {
+		release_metapage(mp);
+		return (rc);
+	}
+
+	/* set the results of the allocation and write the iag.
+	 */
+	diInitInode(ip, iagno, ino, extno, iagp);
+	write_metapage(mp);
+
+	return (0);
+}
+
+
+/*
+ * NAME:	diAllocExt(imap,agno,ip)
+ *
+ * FUNCTION:	add a new extent of free inodes to an iag, allocating
+ *		an inode from this extent to satisfy the current allocation
+ *		request.
+ *
+ *		this routine first tries to find an existing iag with free
+ *		extents through the ag free extent list.  if list is not
+ *		empty, the head of the list will be selected as the home
+ *		of the new extent of free inodes.  otherwise (the list is
+ *		empty), a new iag will be allocated for the ag to contain
+ *		the extent.
+ *
+ *		once an iag has been selected, the free extent summary map
+ *		is used to locate a free extent within the iag and diNewExt()
+ *		is called to initialize the extent, with initialization
+ *		including the allocation of the first inode of the extent
+ *		for the purpose of satisfying this request.
+ *
+ * PARAMETERS:
+ *	imap	- pointer to inode map control structure.
+ *	agno	- allocation group number.
+ *	ip	- pointer to new inode to be filled in on successful return
+ *		  with the disk inode number allocated, its extent address
+ *		  and the start of the ag.
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-ENOSPC	- insufficient disk resources.
+ *	-EIO	- i/o error.
+ */
+static int diAllocExt(struct inomap * imap, int agno, struct inode *ip)
+{
+	int rem, iagno, sword, extno, rc;
+	struct metapage *mp;
+	struct iag *iagp;
+
+	/* check if the ag has any iags with free extents.  if not,
+	 * allocate a new iag for the ag.
+	 */
+	if ((iagno = imap->im_agctl[agno].extfree) < 0) {
+		/* If successful, diNewIAG will obtain the read lock on the
+		 * imap inode.
+		 */
+		if ((rc = diNewIAG(imap, &iagno, agno, &mp))) {
+			return (rc);
+		}
+		iagp = (struct iag *) mp->data;
+
+		/* set the ag number if this a brand new iag
+		 */
+		iagp->agstart =
+		    cpu_to_le64(AGTOBLK(agno, imap->im_ipimap));
+	} else {
+		/* read the iag.
+		 */
+		IREAD_LOCK(imap->im_ipimap, RDWRLOCK_IMAP);
+		if ((rc = diIAGRead(imap, iagno, &mp))) {
+			IREAD_UNLOCK(imap->im_ipimap);
+			jfs_error(ip->i_sb, "error reading iag\n");
+			return rc;
+		}
+		iagp = (struct iag *) mp->data;
+	}
+
+	/* using the free extent summary map, find a free extent.
+	 */
+	for (sword = 0;; sword++) {
+		if (sword >= SMAPSZ) {
+			release_metapage(mp);
+			IREAD_UNLOCK(imap->im_ipimap);
+			jfs_error(ip->i_sb, "free ext summary map not found\n");
+			return -EIO;
+		}
+		if (~iagp->extsmap[sword])
+			break;
+	}
+
+	/* determine the extent number of the free extent.
+	 */
+	rem = diFindFree(le32_to_cpu(iagp->extsmap[sword]), 0);
+	if (rem >= EXTSPERSUM) {
+		release_metapage(mp);
+		IREAD_UNLOCK(imap->im_ipimap);
+		jfs_error(ip->i_sb, "free extent not found\n");
+		return -EIO;
+	}
+	extno = (sword << L2EXTSPERSUM) + rem;
+
+	/* initialize the new extent.
+	 */
+	rc = diNewExt(imap, iagp, extno);
+	IREAD_UNLOCK(imap->im_ipimap);
+	if (rc) {
+		/* something bad happened.  if a new iag was allocated,
+		 * place it back on the inode map's iag free list, and
+		 * clear the ag number information.
+		 */
+		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
+			IAGFREE_LOCK(imap);
+			iagp->iagfree = cpu_to_le32(imap->im_freeiag);
+			imap->im_freeiag = iagno;
+			IAGFREE_UNLOCK(imap);
+		}
+		write_metapage(mp);
+		return (rc);
+	}
+
+	/* set the results of the allocation and write the iag.
+	 */
+	diInitInode(ip, iagno, extno << L2INOSPEREXT, extno, iagp);
+
+	write_metapage(mp);
+
+	return (0);
+}
+
+
+/*
+ * NAME:	diAllocBit(imap,iagp,ino)
+ *
+ * FUNCTION:	allocate a backed inode from an iag.
+ *
+ *		this routine performs the mechanics of allocating a
+ *		specified inode from a backed extent.
+ *
+ *		if the inode to be allocated represents the last free
+ *		inode within the iag, the iag will be removed from the
+ *		ag free inode list.
+ *
+ *		a careful update approach is used to provide consistency
+ *		in the face of updates to multiple buffers.  under this
+ *		approach, all required buffers are obtained before making
+ *		any updates and are held all are updates are complete.
+ *
+ * PRE CONDITION: Already have buffer lock on iagp.  Already have AG lock on
+ *	this AG.  Must have read lock on imap inode.
+ *
+ * PARAMETERS:
+ *	imap	- pointer to inode map control structure.
+ *	iagp	- pointer to iag.
+ *	ino	- inode number to be allocated within the iag.
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-ENOSPC	- insufficient disk resources.
+ *	-EIO	- i/o error.
+ */
+static int diAllocBit(struct inomap * imap, struct iag * iagp, int ino)
+{
+	int extno, bitno, agno, sword, rc;
+	struct metapage *amp = NULL, *bmp = NULL;
+	struct iag *aiagp = NULL, *biagp = NULL;
+	u32 mask;
+
+	/* check if this is the last free inode within the iag.
+	 * if so, it will have to be removed from the ag free
+	 * inode list, so get the iags preceding and following
+	 * it on the list.
+	 */
+	if (iagp->nfreeinos == cpu_to_le32(1)) {
+		if ((int) le32_to_cpu(iagp->inofreefwd) >= 0) {
+			if ((rc =
+			     diIAGRead(imap, le32_to_cpu(iagp->inofreefwd),
+				       &amp)))
+				return (rc);
+			aiagp = (struct iag *) amp->data;
+		}
+
+		if ((int) le32_to_cpu(iagp->inofreeback) >= 0) {
+			if ((rc =
+			     diIAGRead(imap,
+				       le32_to_cpu(iagp->inofreeback),
+				       &bmp))) {
+				if (amp)
+					release_metapage(amp);
+				return (rc);
+			}
+			biagp = (struct iag *) bmp->data;
+		}
+	}
+
+	/* get the ag number, extent number, inode number within
+	 * the extent.
+	 */
+	agno = BLKTOAG(le64_to_cpu(iagp->agstart), JFS_SBI(imap->im_ipimap->i_sb));
+	extno = ino >> L2INOSPEREXT;
+	bitno = ino & (INOSPEREXT - 1);
+
+	/* compute the mask for setting the map.
+	 */
+	mask = HIGHORDER >> bitno;
+
+	/* the inode should be free and backed.
+	 */
+	if (((le32_to_cpu(iagp->pmap[extno]) & mask) != 0) ||
+	    ((le32_to_cpu(iagp->wmap[extno]) & mask) != 0) ||
+	    (addressPXD(&iagp->inoext[extno]) == 0)) {
+		if (amp)
+			release_metapage(amp);
+		if (bmp)
+			release_metapage(bmp);
+
+		jfs_error(imap->im_ipimap->i_sb, "iag inconsistent\n");
+		return -EIO;
+	}
+
+	/* mark the inode as allocated in the working map.
+	 */
+	iagp->wmap[extno] |= cpu_to_le32(mask);
+
+	/* check if all inodes within the extent are now
+	 * allocated.  if so, update the free inode summary
+	 * map to reflect this.
+	 */
+	if (iagp->wmap[extno] == cpu_to_le32(ONES)) {
+		sword = extno >> L2EXTSPERSUM;
+		bitno = extno & (EXTSPERSUM - 1);
+		iagp->inosmap[sword] |= cpu_to_le32(HIGHORDER >> bitno);
+	}
+
+	/* if this was the last free inode in the iag, remove the
+	 * iag from the ag free inode list.
+	 */
+	if (iagp->nfreeinos == cpu_to_le32(1)) {
+		if (amp) {
+			aiagp->inofreeback = iagp->inofreeback;
+			write_metapage(amp);
+		}
+
+		if (bmp) {
+			biagp->inofreefwd = iagp->inofreefwd;
+			write_metapage(bmp);
+		} else {
+			imap->im_agctl[agno].inofree =
+			    le32_to_cpu(iagp->inofreefwd);
+		}
+		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
+	}
+
+	/* update the free inode count at the iag, ag, inode
+	 * map levels.
+	 */
+	le32_add_cpu(&iagp->nfreeinos, -1);
+	imap->im_agctl[agno].numfree -= 1;
+	atomic_dec(&imap->im_numfree);
+
+	return (0);
+}
+
+
+/*
+ * NAME:	diNewExt(imap,iagp,extno)
+ *
+ * FUNCTION:	initialize a new extent of inodes for an iag, allocating
+ *		the first inode of the extent for use for the current
+ *		allocation request.
+ *
+ *		disk resources are allocated for the new extent of inodes
+ *		and the inodes themselves are initialized to reflect their
+ *		existence within the extent (i.e. their inode numbers and
+ *		inode extent addresses are set) and their initial state
+ *		(mode and link count are set to zero).
+ *
+ *		if the iag is new, it is not yet on an ag extent free list
+ *		but will now be placed on this list.
+ *
+ *		if the allocation of the new extent causes the iag to
+ *		have no free extent, the iag will be removed from the
+ *		ag extent free list.
+ *
+ *		if the iag has no free backed inodes, it will be placed
+ *		on the ag free inode list, since the addition of the new
+ *		extent will now cause it to have free inodes.
+ *
+ *		a careful update approach is used to provide consistency
+ *		(i.e. list consistency) in the face of updates to multiple
+ *		buffers.  under this approach, all required buffers are
+ *		obtained before making any updates and are held until all
+ *		updates are complete.
+ *
+ * PRE CONDITION: Already have buffer lock on iagp.  Already have AG lock on
+ *	this AG.  Must have read lock on imap inode.
+ *
+ * PARAMETERS:
+ *	imap	- pointer to inode map control structure.
+ *	iagp	- pointer to iag.
+ *	extno	- extent number.
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-ENOSPC	- insufficient disk resources.
+ *	-EIO	- i/o error.
+ */
+static int diNewExt(struct inomap * imap, struct iag * iagp, int extno)
+{
+	int agno, iagno, fwd, back, freei = 0, sword, rc;
+	struct iag *aiagp = NULL, *biagp = NULL, *ciagp = NULL;
+	struct metapage *amp, *bmp, *cmp, *dmp;
+	struct inode *ipimap;
+	s64 blkno, hint;
+	int i, j;
+	u32 mask;
+	ino_t ino;
+	struct dinode *dp;
+	struct jfs_sb_info *sbi;
+
+	/* better have free extents.
+	 */
+	if (!iagp->nfreeexts) {
+		jfs_error(imap->im_ipimap->i_sb, "no free extents\n");
+		return -EIO;
+	}
+
+	/* get the inode map inode.
+	 */
+	ipimap = imap->im_ipimap;
+	sbi = JFS_SBI(ipimap->i_sb);
+
+	amp = bmp = cmp = NULL;
+
+	/* get the ag and iag numbers for this iag.
+	 */
+	agno = BLKTOAG(le64_to_cpu(iagp->agstart), sbi);
+	iagno = le32_to_cpu(iagp->iagnum);
+
+	/* check if this is the last free extent within the
+	 * iag.  if so, the iag must be removed from the ag
+	 * free extent list, so get the iags preceding and
+	 * following the iag on this list.
+	 */
+	if (iagp->nfreeexts == cpu_to_le32(1)) {
+		if ((fwd = le32_to_cpu(iagp->extfreefwd)) >= 0) {
+			if ((rc = diIAGRead(imap, fwd, &amp)))
+				return (rc);
+			aiagp = (struct iag *) amp->data;
+		}
+
+		if ((back = le32_to_cpu(iagp->extfreeback)) >= 0) {
+			if ((rc = diIAGRead(imap, back, &bmp)))
+				goto error_out;
+			biagp = (struct iag *) bmp->data;
+		}
+	} else {
+		/* the iag has free extents.  if all extents are free
+		 * (as is the case for a newly allocated iag), the iag
+		 * must be added to the ag free extent list, so get
+		 * the iag at the head of the list in preparation for
+		 * adding this iag to this list.
+		 */
+		fwd = back = -1;
+		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
+			if ((fwd = imap->im_agctl[agno].extfree) >= 0) {
+				if ((rc = diIAGRead(imap, fwd, &amp)))
+					goto error_out;
+				aiagp = (struct iag *) amp->data;
+			}
+		}
+	}
+
+	/* check if the iag has no free inodes.  if so, the iag
+	 * will have to be added to the ag free inode list, so get
+	 * the iag at the head of the list in preparation for
+	 * adding this iag to this list.  in doing this, we must
+	 * check if we already have the iag at the head of
+	 * the list in hand.
+	 */
+	if (iagp->nfreeinos == 0) {
+		freei = imap->im_agctl[agno].inofree;
+
+		if (freei >= 0) {
+			if (freei == fwd) {
+				ciagp = aiagp;
+			} else if (freei == back) {
+				ciagp = biagp;
+			} else {
+				if ((rc = diIAGRead(imap, freei, &cmp)))
+					goto error_out;
+				ciagp = (struct iag *) cmp->data;
+			}
+			if (ciagp == NULL) {
+				jfs_error(imap->im_ipimap->i_sb,
+					  "ciagp == NULL\n");
+				rc = -EIO;
+				goto error_out;
+			}
+		}
+	}
+
+	/* allocate disk space for the inode extent.
+	 */
+	if ((extno == 0) || (addressPXD(&iagp->inoext[extno - 1]) == 0))
+		hint = ((s64) agno << sbi->bmap->db_agl2size) - 1;
+	else
+		hint = addressPXD(&iagp->inoext[extno - 1]) +
+		    lengthPXD(&iagp->inoext[extno - 1]) - 1;
+
+	if ((rc = dbAlloc(ipimap, hint, (s64) imap->im_nbperiext, &blkno)))
+		goto error_out;
+
+	/* compute the inode number of the first inode within the
+	 * extent.
+	 */
+	ino = (iagno << L2INOSPERIAG) + (extno << L2INOSPEREXT);
+
+	/* initialize the inodes within the newly allocated extent a
+	 * page at a time.
+	 */
+	for (i = 0; i < imap->im_nbperiext; i += sbi->nbperpage) {
+		/* get a buffer for this page of disk inodes.
+		 */
+		dmp = get_metapage(ipimap, blkno + i, PSIZE, 1);
+		if (dmp == NULL) {
+			rc = -EIO;
+			goto error_out;
+		}
+		dp = (struct dinode *) dmp->data;
+
+		/* initialize the inode number, mode, link count and
+		 * inode extent address.
+		 */
+		for (j = 0; j < INOSPERPAGE; j++, dp++, ino++) {
+			dp->di_inostamp = cpu_to_le32(sbi->inostamp);
+			dp->di_number = cpu_to_le32(ino);
+			dp->di_fileset = cpu_to_le32(FILESYSTEM_I);
+			dp->di_mode = 0;
+			dp->di_nlink = 0;
+			PXDaddress(&(dp->di_ixpxd), blkno);
+			PXDlength(&(dp->di_ixpxd), imap->im_nbperiext);
+		}
+		write_metapage(dmp);
+	}
+
+	/* if this is the last free extent within the iag, remove the
+	 * iag from the ag free extent list.
+	 */
+	if (iagp->nfreeexts == cpu_to_le32(1)) {
+		if (fwd >= 0)
+			aiagp->extfreeback = iagp->extfreeback;
+
+		if (back >= 0)
+			biagp->extfreefwd = iagp->extfreefwd;
+		else
+			imap->im_agctl[agno].extfree =
+			    le32_to_cpu(iagp->extfreefwd);
+
+		iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
+	} else {
+		/* if the iag has all free extents (newly allocated iag),
+		 * add the iag to the ag free extent list.
+		 */
+		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
+			if (fwd >= 0)
+				aiagp->extfreeback = cpu_to_le32(iagno);
+
+			iagp->extfreefwd = cpu_to_le32(fwd);
+			iagp->extfreeback = cpu_to_le32(-1);
+			imap->im_agctl[agno].extfree = iagno;
+		}
+	}
+
+	/* if the iag has no free inodes, add the iag to the
+	 * ag free inode list.
+	 */
+	if (iagp->nfreeinos == 0) {
+		if (freei >= 0)
+			ciagp->inofreeback = cpu_to_le32(iagno);
+
+		iagp->inofreefwd =
+		    cpu_to_le32(imap->im_agctl[agno].inofree);
+		iagp->inofreeback = cpu_to_le32(-1);
+		imap->im_agctl[agno].inofree = iagno;
+	}
+
+	/* initialize the extent descriptor of the extent. */
+	PXDlength(&iagp->inoext[extno], imap->im_nbperiext);
+	PXDaddress(&iagp->inoext[extno], blkno);
+
+	/* initialize the working and persistent map of the extent.
+	 * the working map will be initialized such that
+	 * it indicates the first inode of the extent is allocated.
+	 */
+	iagp->wmap[extno] = cpu_to_le32(HIGHORDER);
+	iagp->pmap[extno] = 0;
+
+	/* update the free inode and free extent summary maps
+	 * for the extent to indicate the extent has free inodes
+	 * and no longer represents a free extent.
+	 */
+	sword = extno >> L2EXTSPERSUM;
+	mask = HIGHORDER >> (extno & (EXTSPERSUM - 1));
+	iagp->extsmap[sword] |= cpu_to_le32(mask);
+	iagp->inosmap[sword] &= cpu_to_le32(~mask);
+
+	/* update the free inode and free extent counts for the
+	 * iag.
+	 */
+	le32_add_cpu(&iagp->nfreeinos, (INOSPEREXT - 1));
+	le32_add_cpu(&iagp->nfreeexts, -1);
+
+	/* update the free and backed inode counts for the ag.
+	 */
+	imap->im_agctl[agno].numfree += (INOSPEREXT - 1);
+	imap->im_agctl[agno].numinos += INOSPEREXT;
+
+	/* update the free and backed inode counts for the inode map.
+	 */
+	atomic_add(INOSPEREXT - 1, &imap->im_numfree);
+	atomic_add(INOSPEREXT, &imap->im_numinos);
+
+	/* write the iags.
+	 */
+	if (amp)
+		write_metapage(amp);
+	if (bmp)
+		write_metapage(bmp);
+	if (cmp)
+		write_metapage(cmp);
+
+	return (0);
+
+      error_out:
+
+	/* release the iags.
+	 */
+	if (amp)
+		release_metapage(amp);
+	if (bmp)
+		release_metapage(bmp);
+	if (cmp)
+		release_metapage(cmp);
+
+	return (rc);
+}
+
+
+/*
+ * NAME:	diNewIAG(imap,iagnop,agno)
+ *
+ * FUNCTION:	allocate a new iag for an allocation group.
+ *
+ *		first tries to allocate the iag from the inode map
+ *		iagfree list:
+ *		if the list has free iags, the head of the list is removed
+ *		and returned to satisfy the request.
+ *		if the inode map's iag free list is empty, the inode map
+ *		is extended to hold a new iag. this new iag is initialized
+ *		and returned to satisfy the request.
+ *
+ * PARAMETERS:
+ *	imap	- pointer to inode map control structure.
+ *	iagnop	- pointer to an iag number set with the number of the
+ *		  newly allocated iag upon successful return.
+ *	agno	- allocation group number.
+ *	bpp	- Buffer pointer to be filled in with new IAG's buffer
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-ENOSPC	- insufficient disk resources.
+ *	-EIO	- i/o error.
+ *
+ * serialization:
+ *	AG lock held on entry/exit;
+ *	write lock on the map is held inside;
+ *	read lock on the map is held on successful completion;
+ *
+ * note: new iag transaction:
+ * . synchronously write iag;
+ * . write log of xtree and inode of imap;
+ * . commit;
+ * . synchronous write of xtree (right to left, bottom to top);
+ * . at start of logredo(): init in-memory imap with one additional iag page;
+ * . at end of logredo(): re-read imap inode to determine
+ *   new imap size;
+ */
+static int
+diNewIAG(struct inomap * imap, int *iagnop, int agno, struct metapage ** mpp)
+{
+	int rc;
+	int iagno, i, xlen;
+	struct inode *ipimap;
+	struct super_block *sb;
+	struct jfs_sb_info *sbi;
+	struct metapage *mp;
+	struct iag *iagp;
+	s64 xaddr = 0;
+	s64 blkno;
+	tid_t tid;
+	struct inode *iplist[1];
+
+	/* pick up pointers to the inode map and mount inodes */
+	ipimap = imap->im_ipimap;
+	sb = ipimap->i_sb;
+	sbi = JFS_SBI(sb);
+
+	/* acquire the free iag lock */
+	IAGFREE_LOCK(imap);
+
+	/* if there are any iags on the inode map free iag list,
+	 * allocate the iag from the head of the list.
+	 */
+	if (imap->im_freeiag >= 0) {
+		/* pick up the iag number at the head of the list */
+		iagno = imap->im_freeiag;
+
+		/* determine the logical block number of the iag */
+		blkno = IAGTOLBLK(iagno, sbi->l2nbperpage);
+	} else {
+		/* no free iags. the inode map will have to be extented
+		 * to include a new iag.
+		 */
+
+		/* acquire inode map lock */
+		IWRITE_LOCK(ipimap, RDWRLOCK_IMAP);
+
+		if (ipimap->i_size >> L2PSIZE != imap->im_nextiag + 1) {
+			IWRITE_UNLOCK(ipimap);
+			IAGFREE_UNLOCK(imap);
+			jfs_error(imap->im_ipimap->i_sb,
+				  "ipimap->i_size is wrong\n");
+			return -EIO;
+		}
+
+
+		/* get the next available iag number */
+		iagno = imap->im_nextiag;
+
+		/* make sure that we have not exceeded the maximum inode
+		 * number limit.
+		 */
+		if (iagno > (MAXIAGS - 1)) {
+			/* release the inode map lock */
+			IWRITE_UNLOCK(ipimap);
+
+			rc = -ENOSPC;
+			goto out;
+		}
+
+		/*
+		 * synchronously append new iag page.
+		 */
+		/* determine the logical address of iag page to append */
+		blkno = IAGTOLBLK(iagno, sbi->l2nbperpage);
+
+		/* Allocate extent for new iag page */
+		xlen = sbi->nbperpage;
+		if ((rc = dbAlloc(ipimap, 0, (s64) xlen, &xaddr))) {
+			/* release the inode map lock */
+			IWRITE_UNLOCK(ipimap);
+
+			goto out;
+		}
+
+		/*
+		 * start transaction of update of the inode map
+		 * addressing structure pointing to the new iag page;
+		 */
+		tid = txBegin(sb, COMMIT_FORCE);
+		mutex_lock(&JFS_IP(ipimap)->commit_mutex);
+
+		/* update the inode map addressing structure to point to it */
+		if ((rc =
+		     xtInsert(tid, ipimap, 0, blkno, xlen, &xaddr, 0))) {
+			txEnd(tid);
+			mutex_unlock(&JFS_IP(ipimap)->commit_mutex);
+			/* Free the blocks allocated for the iag since it was
+			 * not successfully added to the inode map
+			 */
+			dbFree(ipimap, xaddr, (s64) xlen);
+
+			/* release the inode map lock */
+			IWRITE_UNLOCK(ipimap);
+
+			goto out;
+		}
+
+		/* update the inode map's inode to reflect the extension */
+		ipimap->i_size += PSIZE;
+		inode_add_bytes(ipimap, PSIZE);
+
+		/* assign a buffer for the page */
+		mp = get_metapage(ipimap, blkno, PSIZE, 0);
+		if (!mp) {
+			/*
+			 * This is very unlikely since we just created the
+			 * extent, but let's try to handle it correctly
+			 */
+			xtTruncate(tid, ipimap, ipimap->i_size - PSIZE,
+				   COMMIT_PWMAP);
+
+			txAbort(tid, 0);
+			txEnd(tid);
+			mutex_unlock(&JFS_IP(ipimap)->commit_mutex);
+
+			/* release the inode map lock */
+			IWRITE_UNLOCK(ipimap);
+
+			rc = -EIO;
+			goto out;
+		}
+		iagp = (struct iag *) mp->data;
+
+		/* init the iag */
+		memset(iagp, 0, sizeof(struct iag));
+		iagp->iagnum = cpu_to_le32(iagno);
+		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
+		iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
+		iagp->iagfree = cpu_to_le32(-1);
+		iagp->nfreeinos = 0;
+		iagp->nfreeexts = cpu_to_le32(EXTSPERIAG);
+
+		/* initialize the free inode summary map (free extent
+		 * summary map initialization handled by bzero).
+		 */
+		for (i = 0; i < SMAPSZ; i++)
+			iagp->inosmap[i] = cpu_to_le32(ONES);
+
+		/*
+		 * Write and sync the metapage
+		 */
+		flush_metapage(mp);
+
+		/*
+		 * txCommit(COMMIT_FORCE) will synchronously write address
+		 * index pages and inode after commit in careful update order
+		 * of address index pages (right to left, bottom up);
+		 */
+		iplist[0] = ipimap;
+		rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
+
+		txEnd(tid);
+		mutex_unlock(&JFS_IP(ipimap)->commit_mutex);
+
+		duplicateIXtree(sb, blkno, xlen, &xaddr);
+
+		/* update the next available iag number */
+		imap->im_nextiag += 1;
+
+		/* Add the iag to the iag free list so we don't lose the iag
+		 * if a failure happens now.
+		 */
+		imap->im_freeiag = iagno;
+
+		/* Until we have logredo working, we want the imap inode &
+		 * control page to be up to date.
+		 */
+		diSync(ipimap);
+
+		/* release the inode map lock */
+		IWRITE_UNLOCK(ipimap);
+	}
+
+	/* obtain read lock on map */
+	IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
+
+	/* read the iag */
+	if ((rc = diIAGRead(imap, iagno, &mp))) {
+		IREAD_UNLOCK(ipimap);
+		rc = -EIO;
+		goto out;
+	}
+	iagp = (struct iag *) mp->data;
+
+	/* remove the iag from the iag free list */
+	imap->im_freeiag = le32_to_cpu(iagp->iagfree);
+	iagp->iagfree = cpu_to_le32(-1);
+
+	/* set the return iag number and buffer pointer */
+	*iagnop = iagno;
+	*mpp = mp;
+
+      out:
+	/* release the iag free lock */
+	IAGFREE_UNLOCK(imap);
+
+	return (rc);
+}
+
+/*
+ * NAME:	diIAGRead()
+ *
+ * FUNCTION:	get the buffer for the specified iag within a fileset
+ *		or aggregate inode map.
+ *
+ * PARAMETERS:
+ *	imap	- pointer to inode map control structure.
+ *	iagno	- iag number.
+ *	bpp	- point to buffer pointer to be filled in on successful
+ *		  exit.
+ *
+ * SERIALIZATION:
+ *	must have read lock on imap inode
+ *	(When called by diExtendFS, the filesystem is quiesced, therefore
+ *	 the read lock is unnecessary.)
+ *
+ * RETURN VALUES:
+ *	0	- success.
+ *	-EIO	- i/o error.
+ */
+static int diIAGRead(struct inomap * imap, int iagno, struct metapage ** mpp)
+{
+	struct inode *ipimap = imap->im_ipimap;
+	s64 blkno;
+
+	/* compute the logical block number of the iag. */
+	blkno = IAGTOLBLK(iagno, JFS_SBI(ipimap->i_sb)->l2nbperpage);
+
+	/* read the iag. */
+	*mpp = read_metapage(ipimap, blkno, PSIZE, 0);
+	if (*mpp == NULL) {
+		return -EIO;
+	}
+
+	return (0);
+}
+
+/*
+ * NAME:	diFindFree()
+ *
+ * FUNCTION:	find the first free bit in a word starting at
+ *		the specified bit position.
+ *
+ * PARAMETERS:
+ *	word	- word to be examined.
+ *	start	- starting bit position.
+ *
+ * RETURN VALUES:
+ *	bit position of first free bit in the word or 32 if
+ *	no free bits were found.
+ */
+static int diFindFree(u32 word, int start)
+{
+	int bitno;
+	assert(start < 32);
+	/* scan the word for the first free bit. */
+	for (word <<= start, bitno = start; bitno < 32;
+	     bitno++, word <<= 1) {
+		if ((word & HIGHORDER) == 0)
+			break;
+	}
+	return (bitno);
+}
+
+/*
+ * NAME:	diUpdatePMap()
+ *
+ * FUNCTION: Update the persistent map in an IAG for the allocation or
+ *	freeing of the specified inode.
+ *
+ * PRE CONDITIONS: Working map has already been updated for allocate.
+ *
+ * PARAMETERS:
+ *	ipimap	- Incore inode map inode
+ *	inum	- Number of inode to mark in permanent map
+ *	is_free	- If 'true' indicates inode should be marked freed, otherwise
+ *		  indicates inode should be marked allocated.
+ *
+ * RETURN VALUES:
+ *		0 for success
+ */
+int
+diUpdatePMap(struct inode *ipimap,
+	     unsigned long inum, bool is_free, struct tblock * tblk)
+{
+	int rc;
+	struct iag *iagp;
+	struct metapage *mp;
+	int iagno, ino, extno, bitno;
+	struct inomap *imap;
+	u32 mask;
+	struct jfs_log *log;
+	int lsn, difft, diffp;
+	unsigned long flags;
+
+	imap = JFS_IP(ipimap)->i_imap;
+	/* get the iag number containing the inode */
+	iagno = INOTOIAG(inum);
+	/* make sure that the iag is contained within the map */
+	if (iagno >= imap->im_nextiag) {
+		jfs_error(ipimap->i_sb, "the iag is outside the map\n");
+		return -EIO;
+	}
+	/* read the iag */
+	IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
+	rc = diIAGRead(imap, iagno, &mp);
+	IREAD_UNLOCK(ipimap);
+	if (rc)
+		return (rc);
+	metapage_wait_for_io(mp);
+	iagp = (struct iag *) mp->data;
+	/* get the inode number and extent number of the inode within
+	 * the iag and the inode number within the extent.
+	 */
+	ino = inum & (INOSPERIAG - 1);
+	extno = ino >> L2INOSPEREXT;
+	bitno = ino & (INOSPEREXT - 1);
+	mask = HIGHORDER >> bitno;
+	/*
+	 * mark the inode free in persistent map:
+	 */
+	if (is_free) {
+		/* The inode should have been allocated both in working
+		 * map and in persistent map;
+		 * the inode will be freed from working map at the release
+		 * of last reference release;
+		 */
+		if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
+			jfs_error(ipimap->i_sb,
+				  "inode %ld not marked as allocated in wmap!\n",
+				  inum);
+		}
+		if (!(le32_to_cpu(iagp->pmap[extno]) & mask)) {
+			jfs_error(ipimap->i_sb,
+				  "inode %ld not marked as allocated in pmap!\n",
+				  inum);
+		}
+		/* update the bitmap for the extent of the freed inode */
+		iagp->pmap[extno] &= cpu_to_le32(~mask);
+	}
+	/*
+	 * mark the inode allocated in persistent map:
+	 */
+	else {
+		/* The inode should be already allocated in the working map
+		 * and should be free in persistent map;
+		 */
+		if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
+			release_metapage(mp);
+			jfs_error(ipimap->i_sb,
+				  "the inode is not allocated in the working map\n");
+			return -EIO;
+		}
+		if ((le32_to_cpu(iagp->pmap[extno]) & mask) != 0) {
+			release_metapage(mp);
+			jfs_error(ipimap->i_sb,
+				  "the inode is not free in the persistent map\n");
+			return -EIO;
+		}
+		/* update the bitmap for the extent of the allocated inode */
+		iagp->pmap[extno] |= cpu_to_le32(mask);
+	}
+	/*
+	 * update iag lsn
+	 */
+	lsn = tblk->lsn;
+	log = JFS_SBI(tblk->sb)->log;
+	LOGSYNC_LOCK(log, flags);
+	if (mp->lsn != 0) {
+		/* inherit older/smaller lsn */
+		logdiff(difft, lsn, log);
+		logdiff(diffp, mp->lsn, log);
+		if (difft < diffp) {
+			mp->lsn = lsn;
+			/* move mp after tblock in logsync list */
+			list_move(&mp->synclist, &tblk->synclist);
+		}
+		/* inherit younger/larger clsn */
+		assert(mp->clsn);
+		logdiff(difft, tblk->clsn, log);
+		logdiff(diffp, mp->clsn, log);
+		if (difft > diffp)
+			mp->clsn = tblk->clsn;
+	} else {
+		mp->log = log;
+		mp->lsn = lsn;
+		/* insert mp after tblock in logsync list */
+		log->count++;
+		list_add(&mp->synclist, &tblk->synclist);
+		mp->clsn = tblk->clsn;
+	}
+	LOGSYNC_UNLOCK(log, flags);
+	write_metapage(mp);
+	return (0);
+}
+
+/*
+ *	diExtendFS()
+ *
+ * function: update imap for extendfs();
+ *
+ * note: AG size has been increased s.t. each k old contiguous AGs are
+ * coalesced into a new AG;
+ */
+int diExtendFS(struct inode *ipimap, struct inode *ipbmap)
+{
+	int rc, rcx = 0;
+	struct inomap *imap = JFS_IP(ipimap)->i_imap;
+	struct iag *iagp = NULL, *hiagp = NULL;
+	struct bmap *mp = JFS_SBI(ipbmap->i_sb)->bmap;
+	struct metapage *bp, *hbp;
+	int i, n, head;
+	int numinos, xnuminos = 0, xnumfree = 0;
+	s64 agstart;
+
+	jfs_info("diExtendFS: nextiag:%d numinos:%d numfree:%d",
+		   imap->im_nextiag, atomic_read(&imap->im_numinos),
+		   atomic_read(&imap->im_numfree));
+
+	/*
+	 *	reconstruct imap
+	 *
+	 * coalesce contiguous k (newAGSize/oldAGSize) AGs;
+	 * i.e., (AGi, ..., AGj) where i = k*n and j = k*(n+1) - 1 to AGn;
+	 * note: new AG size = old AG size * (2**x).
+	 */
+
+	/* init per AG control information im_agctl[] */
+	for (i = 0; i < MAXAG; i++) {
+		imap->im_agctl[i].inofree = -1;
+		imap->im_agctl[i].extfree = -1;
+		imap->im_agctl[i].numinos = 0;	/* number of backed inodes */
+		imap->im_agctl[i].numfree = 0;	/* number of free backed inodes */
+	}
+
+	/*
+	 *	process each iag page of the map.
+	 *
+	 * rebuild AG Free Inode List, AG Free Inode Extent List;
+	 */
+	for (i = 0; i < imap->im_nextiag; i++) {
+		if ((rc = diIAGRead(imap, i, &bp))) {
+			rcx = rc;
+			continue;
+		}
+		iagp = (struct iag *) bp->data;
+		if (le32_to_cpu(iagp->iagnum) != i) {
+			release_metapage(bp);
+			jfs_error(ipimap->i_sb, "unexpected value of iagnum\n");
+			return -EIO;
+		}
+
+		/* leave free iag in the free iag list */
+		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
+			release_metapage(bp);
+			continue;
+		}
+
+		agstart = le64_to_cpu(iagp->agstart);
+		n = agstart >> mp->db_agl2size;
+		iagp->agstart = cpu_to_le64((s64)n << mp->db_agl2size);
+
+		/* compute backed inodes */
+		numinos = (EXTSPERIAG - le32_to_cpu(iagp->nfreeexts))
+		    << L2INOSPEREXT;
+		if (numinos > 0) {
+			/* merge AG backed inodes */
+			imap->im_agctl[n].numinos += numinos;
+			xnuminos += numinos;
+		}
+
+		/* if any backed free inodes, insert at AG free inode list */
+		if ((int) le32_to_cpu(iagp->nfreeinos) > 0) {
+			if ((head = imap->im_agctl[n].inofree) == -1) {
+				iagp->inofreefwd = cpu_to_le32(-1);
+				iagp->inofreeback = cpu_to_le32(-1);
+			} else {
+				if ((rc = diIAGRead(imap, head, &hbp))) {
+					rcx = rc;
+					goto nextiag;
+				}
+				hiagp = (struct iag *) hbp->data;
+				hiagp->inofreeback = iagp->iagnum;
+				iagp->inofreefwd = cpu_to_le32(head);
+				iagp->inofreeback = cpu_to_le32(-1);
+				write_metapage(hbp);
+			}
+
+			imap->im_agctl[n].inofree =
+			    le32_to_cpu(iagp->iagnum);
+
+			/* merge AG backed free inodes */
+			imap->im_agctl[n].numfree +=
+			    le32_to_cpu(iagp->nfreeinos);
+			xnumfree += le32_to_cpu(iagp->nfreeinos);
+		}
+
+		/* if any free extents, insert at AG free extent list */
+		if (le32_to_cpu(iagp->nfreeexts) > 0) {
+			if ((head = imap->im_agctl[n].extfree) == -1) {
+				iagp->extfreefwd = cpu_to_le32(-1);
+				iagp->extfreeback = cpu_to_le32(-1);
+			} else {
+				if ((rc = diIAGRead(imap, head, &hbp))) {
+					rcx = rc;
+					goto nextiag;
+				}
+				hiagp = (struct iag *) hbp->data;
+				hiagp->extfreeback = iagp->iagnum;
+				iagp->extfreefwd = cpu_to_le32(head);
+				iagp->extfreeback = cpu_to_le32(-1);
+				write_metapage(hbp);
+			}
+
+			imap->im_agctl[n].extfree =
+			    le32_to_cpu(iagp->iagnum);
+		}
+
+	      nextiag:
+		write_metapage(bp);
+	}
+
+	if (xnuminos != atomic_read(&imap->im_numinos) ||
+	    xnumfree != atomic_read(&imap->im_numfree)) {
+		jfs_error(ipimap->i_sb, "numinos or numfree incorrect\n");
+		return -EIO;
+	}
+
+	return rcx;
+}
+
+
+/*
+ *	duplicateIXtree()
+ *
+ * serialization: IWRITE_LOCK held on entry/exit
+ *
+ * note: shadow page with regular inode (rel.2);
+ */
+static void duplicateIXtree(struct super_block *sb, s64 blkno,
+			    int xlen, s64 *xaddr)
+{
+	struct jfs_superblock *j_sb;
+	struct buffer_head *bh;
+	struct inode *ip;
+	tid_t tid;
+
+	/* if AIT2 ipmap2 is bad, do not try to update it */
+	if (JFS_SBI(sb)->mntflag & JFS_BAD_SAIT)	/* s_flag */
+		return;
+	ip = diReadSpecial(sb, FILESYSTEM_I, 1);
+	if (ip == NULL) {
+		JFS_SBI(sb)->mntflag |= JFS_BAD_SAIT;
+		if (readSuper(sb, &bh))
+			return;
+		j_sb = (struct jfs_superblock *)bh->b_data;
+		j_sb->s_flag |= cpu_to_le32(JFS_BAD_SAIT);
+
+		mark_buffer_dirty(bh);
+		sync_dirty_buffer(bh);
+		brelse(bh);
+		return;
+	}
+
+	/* start transaction */
+	tid = txBegin(sb, COMMIT_FORCE);
+	/* update the inode map addressing structure to point to it */
+	if (xtInsert(tid, ip, 0, blkno, xlen, xaddr, 0)) {
+		JFS_SBI(sb)->mntflag |= JFS_BAD_SAIT;
+		txAbort(tid, 1);
+		goto cleanup;
+
+	}
+	/* update the inode map's inode to reflect the extension */
+	ip->i_size += PSIZE;
+	inode_add_bytes(ip, PSIZE);
+	txCommit(tid, 1, &ip, COMMIT_FORCE);
+      cleanup:
+	txEnd(tid);
+	diFreeSpecial(ip);
+}
+
+/*
+ * NAME:	copy_from_dinode()
+ *
+ * FUNCTION:	Copies inode info from disk inode to in-memory inode
+ *
+ * RETURN VALUES:
+ *	0	- success
+ *	-ENOMEM	- insufficient memory
+ */
+static int copy_from_dinode(struct dinode * dip, struct inode *ip)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+
+	jfs_ip->fileset = le32_to_cpu(dip->di_fileset);
+	jfs_ip->mode2 = le32_to_cpu(dip->di_mode);
+	jfs_set_inode_flags(ip);
+
+	ip->i_mode = le32_to_cpu(dip->di_mode) & 0xffff;
+	if (sbi->umask != -1) {
+		ip->i_mode = (ip->i_mode & ~0777) | (0777 & ~sbi->umask);
+		/* For directories, add x permission if r is allowed by umask */
+		if (S_ISDIR(ip->i_mode)) {
+			if (ip->i_mode & 0400)
+				ip->i_mode |= 0100;
+			if (ip->i_mode & 0040)
+				ip->i_mode |= 0010;
+			if (ip->i_mode & 0004)
+				ip->i_mode |= 0001;
+		}
+	}
+	set_nlink(ip, le32_to_cpu(dip->di_nlink));
+
+	jfs_ip->saved_uid = make_kuid(&init_user_ns, le32_to_cpu(dip->di_uid));
+	if (!uid_valid(sbi->uid))
+		ip->i_uid = jfs_ip->saved_uid;
+	else {
+		ip->i_uid = sbi->uid;
+	}
+
+	jfs_ip->saved_gid = make_kgid(&init_user_ns, le32_to_cpu(dip->di_gid));
+	if (!gid_valid(sbi->gid))
+		ip->i_gid = jfs_ip->saved_gid;
+	else {
+		ip->i_gid = sbi->gid;
+	}
+
+	ip->i_size = le64_to_cpu(dip->di_size);
+	ip->i_atime.tv_sec = le32_to_cpu(dip->di_atime.tv_sec);
+	ip->i_atime.tv_nsec = le32_to_cpu(dip->di_atime.tv_nsec);
+	ip->i_mtime.tv_sec = le32_to_cpu(dip->di_mtime.tv_sec);
+	ip->i_mtime.tv_nsec = le32_to_cpu(dip->di_mtime.tv_nsec);
+	ip->i_ctime.tv_sec = le32_to_cpu(dip->di_ctime.tv_sec);
+	ip->i_ctime.tv_nsec = le32_to_cpu(dip->di_ctime.tv_nsec);
+	ip->i_blocks = LBLK2PBLK(ip->i_sb, le64_to_cpu(dip->di_nblocks));
+	ip->i_generation = le32_to_cpu(dip->di_gen);
+
+	jfs_ip->ixpxd = dip->di_ixpxd;	/* in-memory pxd's are little-endian */
+	jfs_ip->acl = dip->di_acl;	/* as are dxd's */
+	jfs_ip->ea = dip->di_ea;
+	jfs_ip->next_index = le32_to_cpu(dip->di_next_index);
+	jfs_ip->otime = le32_to_cpu(dip->di_otime.tv_sec);
+	jfs_ip->acltype = le32_to_cpu(dip->di_acltype);
+
+	if (S_ISCHR(ip->i_mode) || S_ISBLK(ip->i_mode)) {
+		jfs_ip->dev = le32_to_cpu(dip->di_rdev);
+		ip->i_rdev = new_decode_dev(jfs_ip->dev);
+	}
+
+	if (S_ISDIR(ip->i_mode)) {
+		memcpy(&jfs_ip->u.dir, &dip->u._dir, 384);
+	} else if (S_ISREG(ip->i_mode) || S_ISLNK(ip->i_mode)) {
+		memcpy(&jfs_ip->i_xtroot, &dip->di_xtroot, 288);
+	} else
+		memcpy(&jfs_ip->i_inline_ea, &dip->di_inlineea, 128);
+
+	/* Zero the in-memory-only stuff */
+	jfs_ip->cflag = 0;
+	jfs_ip->btindex = 0;
+	jfs_ip->btorder = 0;
+	jfs_ip->bxflag = 0;
+	jfs_ip->blid = 0;
+	jfs_ip->atlhead = 0;
+	jfs_ip->atltail = 0;
+	jfs_ip->xtlid = 0;
+	return (0);
+}
+
+/*
+ * NAME:	copy_to_dinode()
+ *
+ * FUNCTION:	Copies inode info from in-memory inode to disk inode
+ */
+static void copy_to_dinode(struct dinode * dip, struct inode *ip)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+
+	dip->di_fileset = cpu_to_le32(jfs_ip->fileset);
+	dip->di_inostamp = cpu_to_le32(sbi->inostamp);
+	dip->di_number = cpu_to_le32(ip->i_ino);
+	dip->di_gen = cpu_to_le32(ip->i_generation);
+	dip->di_size = cpu_to_le64(ip->i_size);
+	dip->di_nblocks = cpu_to_le64(PBLK2LBLK(ip->i_sb, ip->i_blocks));
+	dip->di_nlink = cpu_to_le32(ip->i_nlink);
+	if (!uid_valid(sbi->uid))
+		dip->di_uid = cpu_to_le32(i_uid_read(ip));
+	else
+		dip->di_uid =cpu_to_le32(from_kuid(&init_user_ns,
+						   jfs_ip->saved_uid));
+	if (!gid_valid(sbi->gid))
+		dip->di_gid = cpu_to_le32(i_gid_read(ip));
+	else
+		dip->di_gid = cpu_to_le32(from_kgid(&init_user_ns,
+						    jfs_ip->saved_gid));
+	/*
+	 * mode2 is only needed for storing the higher order bits.
+	 * Trust i_mode for the lower order ones
+	 */
+	if (sbi->umask == -1)
+		dip->di_mode = cpu_to_le32((jfs_ip->mode2 & 0xffff0000) |
+					   ip->i_mode);
+	else /* Leave the original permissions alone */
+		dip->di_mode = cpu_to_le32(jfs_ip->mode2);
+
+	dip->di_atime.tv_sec = cpu_to_le32(ip->i_atime.tv_sec);
+	dip->di_atime.tv_nsec = cpu_to_le32(ip->i_atime.tv_nsec);
+	dip->di_ctime.tv_sec = cpu_to_le32(ip->i_ctime.tv_sec);
+	dip->di_ctime.tv_nsec = cpu_to_le32(ip->i_ctime.tv_nsec);
+	dip->di_mtime.tv_sec = cpu_to_le32(ip->i_mtime.tv_sec);
+	dip->di_mtime.tv_nsec = cpu_to_le32(ip->i_mtime.tv_nsec);
+	dip->di_ixpxd = jfs_ip->ixpxd;	/* in-memory pxd's are little-endian */
+	dip->di_acl = jfs_ip->acl;	/* as are dxd's */
+	dip->di_ea = jfs_ip->ea;
+	dip->di_next_index = cpu_to_le32(jfs_ip->next_index);
+	dip->di_otime.tv_sec = cpu_to_le32(jfs_ip->otime);
+	dip->di_otime.tv_nsec = 0;
+	dip->di_acltype = cpu_to_le32(jfs_ip->acltype);
+	if (S_ISCHR(ip->i_mode) || S_ISBLK(ip->i_mode))
+		dip->di_rdev = cpu_to_le32(jfs_ip->dev);
+}
diff --git a/fs/jfs/jfs_imap.h b/fs/jfs/jfs_imap.h
new file mode 100644
index 000000000..dd7409feb
--- /dev/null
+++ b/fs/jfs/jfs_imap.h
@@ -0,0 +1,162 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ */
+#ifndef	_H_JFS_IMAP
+#define _H_JFS_IMAP
+
+#include "jfs_txnmgr.h"
+
+/*
+ *	jfs_imap.h: disk inode manager
+ */
+
+#define	EXTSPERIAG	128	/* number of disk inode extent per iag	*/
+#define IMAPBLKNO	0	/* lblkno of dinomap within inode map	*/
+#define SMAPSZ		4	/* number of words per summary map	*/
+#define	EXTSPERSUM	32	/* number of extents per summary map entry */
+#define	L2EXTSPERSUM	5	/* l2 number of extents per summary map */
+#define	PGSPERIEXT	4	/* number of 4K pages per dinode extent */
+#define	MAXIAGS		((1<<20)-1)	/* maximum number of iags	*/
+#define	MAXAG		128	/* maximum number of allocation groups	*/
+
+#define AMAPSIZE	512	/* bytes in the IAG allocation maps */
+#define SMAPSIZE	16	/* bytes in the IAG summary maps */
+
+/* convert inode number to iag number */
+#define	INOTOIAG(ino)	((ino) >> L2INOSPERIAG)
+
+/* convert iag number to logical block number of the iag page */
+#define IAGTOLBLK(iagno,l2nbperpg)	(((iagno) + 1) << (l2nbperpg))
+
+/* get the starting block number of the 4K page of an inode extent
+ * that contains ino.
+ */
+#define INOPBLK(pxd,ino,l2nbperpg)	(addressPXD((pxd)) +		\
+	((((ino) & (INOSPEREXT-1)) >> L2INOSPERPAGE) << (l2nbperpg)))
+
+/*
+ *	inode allocation map:
+ *
+ * inode allocation map consists of
+ * . the inode map control page and
+ * . inode allocation group pages (per 4096 inodes)
+ * which are addressed by standard JFS xtree.
+ */
+/*
+ *	inode allocation group page (per 4096 inodes of an AG)
+ */
+struct iag {
+	__le64 agstart;		/* 8: starting block of ag		*/
+	__le32 iagnum;		/* 4: inode allocation group number	*/
+	__le32 inofreefwd;	/* 4: ag inode free list forward	*/
+	__le32 inofreeback;	/* 4: ag inode free list back		*/
+	__le32 extfreefwd;	/* 4: ag inode extent free list forward	*/
+	__le32 extfreeback;	/* 4: ag inode extent free list back	*/
+	__le32 iagfree;		/* 4: iag free list			*/
+
+	/* summary map: 1 bit per inode extent */
+	__le32 inosmap[SMAPSZ];	/* 16: sum map of mapwords w/ free inodes;
+				 *	note: this indicates free and backed
+				 *	inodes, if the extent is not backed the
+				 *	value will be 1.  if the extent is
+				 *	backed but all inodes are being used the
+				 *	value will be 1.  if the extent is
+				 *	backed but at least one of the inodes is
+				 *	free the value will be 0.
+				 */
+	__le32 extsmap[SMAPSZ];	/* 16: sum map of mapwords w/ free extents */
+	__le32 nfreeinos;	/* 4: number of free inodes		*/
+	__le32 nfreeexts;	/* 4: number of free extents		*/
+	/* (72) */
+	u8 pad[1976];		/* 1976: pad to 2048 bytes */
+	/* allocation bit map: 1 bit per inode (0 - free, 1 - allocated) */
+	__le32 wmap[EXTSPERIAG];	/* 512: working allocation map */
+	__le32 pmap[EXTSPERIAG];	/* 512: persistent allocation map */
+	pxd_t inoext[EXTSPERIAG];	/* 1024: inode extent addresses */
+};				/* (4096) */
+
+/*
+ *	per AG control information (in inode map control page)
+ */
+struct iagctl_disk {
+	__le32 inofree;		/* 4: free inode list anchor		*/
+	__le32 extfree;		/* 4: free extent list anchor		*/
+	__le32 numinos;		/* 4: number of backed inodes		*/
+	__le32 numfree;		/* 4: number of free inodes		*/
+};				/* (16) */
+
+struct iagctl {
+	int inofree;		/* free inode list anchor		*/
+	int extfree;		/* free extent list anchor		*/
+	int numinos;		/* number of backed inodes		*/
+	int numfree;		/* number of free inodes		*/
+};
+
+/*
+ *	per fileset/aggregate inode map control page
+ */
+struct dinomap_disk {
+	__le32 in_freeiag;	/* 4: free iag list anchor	*/
+	__le32 in_nextiag;	/* 4: next free iag number	*/
+	__le32 in_numinos;	/* 4: num of backed inodes	*/
+	__le32 in_numfree;	/* 4: num of free backed inodes */
+	__le32 in_nbperiext;	/* 4: num of blocks per inode extent */
+	__le32 in_l2nbperiext;	/* 4: l2 of in_nbperiext	*/
+	__le32 in_diskblock;	/* 4: for standalone test driver */
+	__le32 in_maxag;	/* 4: for standalone test driver */
+	u8 pad[2016];		/* 2016: pad to 2048		*/
+	struct iagctl_disk in_agctl[MAXAG]; /* 2048: AG control information */
+};				/* (4096) */
+
+struct dinomap {
+	int in_freeiag;		/* free iag list anchor		*/
+	int in_nextiag;		/* next free iag number		*/
+	int in_numinos;		/* num of backed inodes		*/
+	int in_numfree;		/* num of free backed inodes	*/
+	int in_nbperiext;	/* num of blocks per inode extent */
+	int in_l2nbperiext;	/* l2 of in_nbperiext		*/
+	int in_diskblock;	/* for standalone test driver	*/
+	int in_maxag;		/* for standalone test driver	*/
+	struct iagctl in_agctl[MAXAG];	/* AG control information */
+};
+
+/*
+ *	In-core inode map control page
+ */
+struct inomap {
+	struct dinomap im_imap;		/* 4096: inode allocation control */
+	struct inode *im_ipimap;	/* 4: ptr to inode for imap	*/
+	struct mutex im_freelock;	/* 4: iag free list lock	*/
+	struct mutex im_aglock[MAXAG];	/* 512: per AG locks		*/
+	u32 *im_DBGdimap;
+	atomic_t im_numinos;	/* num of backed inodes */
+	atomic_t im_numfree;	/* num of free backed inodes */
+};
+
+#define	im_freeiag	im_imap.in_freeiag
+#define	im_nextiag	im_imap.in_nextiag
+#define	im_agctl	im_imap.in_agctl
+#define	im_nbperiext	im_imap.in_nbperiext
+#define	im_l2nbperiext	im_imap.in_l2nbperiext
+
+/* for standalone testdriver
+ */
+#define	im_diskblock	im_imap.in_diskblock
+#define	im_maxag	im_imap.in_maxag
+
+extern int diFree(struct inode *);
+extern int diAlloc(struct inode *, bool, struct inode *);
+extern int diSync(struct inode *);
+/* external references */
+extern int diUpdatePMap(struct inode *ipimap, unsigned long inum,
+			bool is_free, struct tblock * tblk);
+extern int diExtendFS(struct inode *ipimap, struct inode *ipbmap);
+extern int diMount(struct inode *);
+extern int diUnmount(struct inode *, int);
+extern int diRead(struct inode *);
+extern struct inode *diReadSpecial(struct super_block *, ino_t, int);
+extern void diWriteSpecial(struct inode *, int);
+extern void diFreeSpecial(struct inode *);
+extern int diWrite(tid_t tid, struct inode *);
+#endif				/* _H_JFS_IMAP */
diff --git a/fs/jfs/jfs_incore.h b/fs/jfs/jfs_incore.h
new file mode 100644
index 000000000..721def69e
--- /dev/null
+++ b/fs/jfs/jfs_incore.h
@@ -0,0 +1,226 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+#ifndef _H_JFS_INCORE
+#define _H_JFS_INCORE
+
+#include <linux/mutex.h>
+#include <linux/rwsem.h>
+#include <linux/slab.h>
+#include <linux/bitops.h>
+#include <linux/uuid.h>
+
+#include "jfs_types.h"
+#include "jfs_xtree.h"
+#include "jfs_dtree.h"
+
+/*
+ * JFS magic number
+ */
+#define JFS_SUPER_MAGIC 0x3153464a /* "JFS1" */
+
+/*
+ * JFS-private inode information
+ */
+struct jfs_inode_info {
+	int	fileset;	/* fileset number (always 16)*/
+	uint	mode2;		/* jfs-specific mode		*/
+	kuid_t	saved_uid;	/* saved for uid mount option */
+	kgid_t	saved_gid;	/* saved for gid mount option */
+	pxd_t	ixpxd;		/* inode extent descriptor	*/
+	dxd_t	acl;		/* dxd describing acl	*/
+	dxd_t	ea;		/* dxd describing ea	*/
+	time64_t otime;		/* time created	*/
+	uint	next_index;	/* next available directory entry index */
+	int	acltype;	/* Type of ACL	*/
+	short	btorder;	/* access order	*/
+	short	btindex;	/* btpage entry index*/
+	struct inode *ipimap;	/* inode map			*/
+	unsigned long cflag;	/* commit flags		*/
+	u64	agstart;	/* agstart of the containing IAG */
+	u16	bxflag;		/* xflag of pseudo buffer?	*/
+	unchar	pad;
+	signed char active_ag;	/* ag currently allocating from	*/
+	lid_t	blid;		/* lid of pseudo buffer?	*/
+	lid_t	atlhead;	/* anonymous tlock list head	*/
+	lid_t	atltail;	/* anonymous tlock list tail	*/
+	spinlock_t ag_lock;	/* protects active_ag		*/
+	struct list_head anon_inode_list; /* inodes having anonymous txns */
+	/*
+	 * rdwrlock serializes xtree between reads & writes and synchronizes
+	 * changes to special inodes.  It's use would be redundant on
+	 * directories since the i_mutex taken in the VFS is sufficient.
+	 */
+	struct rw_semaphore rdwrlock;
+	/*
+	 * commit_mutex serializes transaction processing on an inode.
+	 * It must be taken after beginning a transaction (txBegin), since
+	 * dirty inodes may be committed while a new transaction on the
+	 * inode is blocked in txBegin or TxBeginAnon
+	 */
+	struct mutex commit_mutex;
+	/* xattr_sem allows us to access the xattrs without taking i_mutex */
+	struct rw_semaphore xattr_sem;
+	lid_t	xtlid;		/* lid of xtree lock on directory */
+	union {
+		struct {
+			xtpage_t _xtroot;	/* 288: xtree root */
+			struct inomap *_imap;	/* 4: inode map header	*/
+		} file;
+		struct {
+			struct dir_table_slot _table[12]; /* 96: dir index */
+			dtroot_t _dtroot;	/* 288: dtree root */
+		} dir;
+		struct {
+			unchar _unused[16];	/* 16: */
+			dxd_t _dxd;		/* 16: */
+			/* _inline may overflow into _inline_ea when needed */
+			/* _inline_ea may overlay the last part of
+			 * file._xtroot if maxentry = XTROOTINITSLOT
+			 */
+			union {
+				struct {
+					/* 128: inline symlink */
+					unchar _inline[128];
+					/* 128: inline extended attr */
+					unchar _inline_ea[128];
+				};
+				unchar _inline_all[256];
+			};
+		} link;
+	} u;
+#ifdef CONFIG_QUOTA
+	struct dquot *i_dquot[MAXQUOTAS];
+#endif
+	u32 dev;	/* will die when we get wide dev_t */
+	struct inode	vfs_inode;
+};
+#define i_xtroot u.file._xtroot
+#define i_imap u.file._imap
+#define i_dirtable u.dir._table
+#define i_dtroot u.dir._dtroot
+#define i_inline u.link._inline
+#define i_inline_ea u.link._inline_ea
+#define i_inline_all u.link._inline_all
+
+#define IREAD_LOCK(ip, subclass) \
+	down_read_nested(&JFS_IP(ip)->rdwrlock, subclass)
+#define IREAD_UNLOCK(ip)	up_read(&JFS_IP(ip)->rdwrlock)
+#define IWRITE_LOCK(ip, subclass) \
+	down_write_nested(&JFS_IP(ip)->rdwrlock, subclass)
+#define IWRITE_UNLOCK(ip)	up_write(&JFS_IP(ip)->rdwrlock)
+
+/*
+ * cflag
+ */
+enum cflags {
+	COMMIT_Nolink,		/* inode committed with zero link count */
+	COMMIT_Inlineea,	/* commit inode inline EA */
+	COMMIT_Freewmap,	/* free WMAP at iClose() */
+	COMMIT_Dirty,		/* Inode is really dirty */
+	COMMIT_Dirtable,	/* commit changes to di_dirtable */
+	COMMIT_Stale,		/* data extent is no longer valid */
+	COMMIT_Synclist,	/* metadata pages on group commit synclist */
+};
+
+/*
+ * commit_mutex nesting subclasses:
+ */
+enum commit_mutex_class
+{
+	COMMIT_MUTEX_PARENT,
+	COMMIT_MUTEX_CHILD,
+	COMMIT_MUTEX_SECOND_PARENT,	/* Renaming */
+	COMMIT_MUTEX_VICTIM		/* Inode being unlinked due to rename */
+};
+
+/*
+ * rdwrlock subclasses:
+ * The dmap inode may be locked while a normal inode or the imap inode are
+ * locked.
+ */
+enum rdwrlock_class
+{
+	RDWRLOCK_NORMAL,
+	RDWRLOCK_IMAP,
+	RDWRLOCK_DMAP
+};
+
+#define set_cflag(flag, ip)	set_bit(flag, &(JFS_IP(ip)->cflag))
+#define clear_cflag(flag, ip)	clear_bit(flag, &(JFS_IP(ip)->cflag))
+#define test_cflag(flag, ip)	test_bit(flag, &(JFS_IP(ip)->cflag))
+#define test_and_clear_cflag(flag, ip) \
+	test_and_clear_bit(flag, &(JFS_IP(ip)->cflag))
+/*
+ * JFS-private superblock information.
+ */
+struct jfs_sb_info {
+	struct super_block *sb;		/* Point back to vfs super block */
+	unsigned long	mntflag;	/* aggregate attributes	*/
+	struct inode	*ipbmap;	/* block map inode		*/
+	struct inode	*ipaimap;	/* aggregate inode map inode	*/
+	struct inode	*ipaimap2;	/* secondary aimap inode	*/
+	struct inode	*ipimap;	/* aggregate inode map inode	*/
+	struct jfs_log	*log;		/* log			*/
+	struct list_head log_list;	/* volumes associated with a journal */
+	short		bsize;		/* logical block size	*/
+	short		l2bsize;	/* log2 logical block size	*/
+	short		nbperpage;	/* blocks per page		*/
+	short		l2nbperpage;	/* log2 blocks per page	*/
+	short		l2niperblk;	/* log2 inodes per page	*/
+	dev_t		logdev;		/* external log device	*/
+	uint		aggregate;	/* volume identifier in log record */
+	pxd_t		logpxd;		/* pxd describing log	*/
+	pxd_t		fsckpxd;	/* pxd describing fsck wkspc */
+	pxd_t		ait2;		/* pxd describing AIT copy	*/
+	uuid_t		uuid;		/* 128-bit uuid for volume	*/
+	uuid_t		loguuid;	/* 128-bit uuid for log	*/
+	/*
+	 * commit_state is used for synchronization of the jfs_commit
+	 * threads.  It is protected by LAZY_LOCK().
+	 */
+	int		commit_state;	/* commit state */
+	/* Formerly in ipimap */
+	uint		gengen;		/* inode generation generator*/
+	uint		inostamp;	/* shows inode belongs to fileset*/
+
+	/* Formerly in ipbmap */
+	struct bmap	*bmap;		/* incore bmap descriptor	*/
+	struct nls_table *nls_tab;	/* current codepage		*/
+	struct inode *direct_inode;	/* metadata inode */
+	uint		state;		/* mount/recovery state	*/
+	unsigned long	flag;		/* mount time flags */
+	uint		p_state;	/* state prior to going no integrity */
+	kuid_t		uid;		/* uid to override on-disk uid */
+	kgid_t		gid;		/* gid to override on-disk gid */
+	uint		umask;		/* umask to override on-disk umask */
+	uint		minblks_trim;	/* minimum blocks, for online trim */
+};
+
+/* jfs_sb_info commit_state */
+#define IN_LAZYCOMMIT 1
+
+static inline struct jfs_inode_info *JFS_IP(struct inode *inode)
+{
+	return container_of(inode, struct jfs_inode_info, vfs_inode);
+}
+
+static inline int jfs_dirtable_inline(struct inode *inode)
+{
+	return (JFS_IP(inode)->next_index <= (MAX_INLINE_DIRTABLE_ENTRY + 1));
+}
+
+static inline struct jfs_sb_info *JFS_SBI(struct super_block *sb)
+{
+	return sb->s_fs_info;
+}
+
+static inline int isReadOnly(struct inode *inode)
+{
+	if (JFS_SBI(inode->i_sb)->log)
+		return 0;
+	return 1;
+}
+#endif /* _H_JFS_INCORE */
diff --git a/fs/jfs/jfs_inode.c b/fs/jfs/jfs_inode.c
new file mode 100644
index 000000000..59379089e
--- /dev/null
+++ b/fs/jfs/jfs_inode.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+
+#include <linux/fs.h>
+#include <linux/quotaops.h>
+#include "jfs_incore.h"
+#include "jfs_inode.h"
+#include "jfs_filsys.h"
+#include "jfs_imap.h"
+#include "jfs_dinode.h"
+#include "jfs_debug.h"
+
+
+void jfs_set_inode_flags(struct inode *inode)
+{
+	unsigned int flags = JFS_IP(inode)->mode2;
+	unsigned int new_fl = 0;
+
+	if (flags & JFS_IMMUTABLE_FL)
+		new_fl |= S_IMMUTABLE;
+	if (flags & JFS_APPEND_FL)
+		new_fl |= S_APPEND;
+	if (flags & JFS_NOATIME_FL)
+		new_fl |= S_NOATIME;
+	if (flags & JFS_DIRSYNC_FL)
+		new_fl |= S_DIRSYNC;
+	if (flags & JFS_SYNC_FL)
+		new_fl |= S_SYNC;
+	inode_set_flags(inode, new_fl, S_IMMUTABLE | S_APPEND | S_NOATIME |
+			S_DIRSYNC | S_SYNC);
+}
+
+/*
+ * NAME:	ialloc()
+ *
+ * FUNCTION:	Allocate a new inode
+ *
+ */
+struct inode *ialloc(struct inode *parent, umode_t mode)
+{
+	struct super_block *sb = parent->i_sb;
+	struct inode *inode;
+	struct jfs_inode_info *jfs_inode;
+	int rc;
+
+	inode = new_inode(sb);
+	if (!inode) {
+		jfs_warn("ialloc: new_inode returned NULL!");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	jfs_inode = JFS_IP(inode);
+
+	rc = diAlloc(parent, S_ISDIR(mode), inode);
+	if (rc) {
+		jfs_warn("ialloc: diAlloc returned %d!", rc);
+		goto fail_put;
+	}
+
+	if (insert_inode_locked(inode) < 0) {
+		rc = -EINVAL;
+		goto fail_put;
+	}
+
+	inode_init_owner(&init_user_ns, inode, parent, mode);
+	/*
+	 * New inodes need to save sane values on disk when
+	 * uid & gid mount options are used
+	 */
+	jfs_inode->saved_uid = inode->i_uid;
+	jfs_inode->saved_gid = inode->i_gid;
+
+	/*
+	 * Allocate inode to quota.
+	 */
+	rc = dquot_initialize(inode);
+	if (rc)
+		goto fail_drop;
+	rc = dquot_alloc_inode(inode);
+	if (rc)
+		goto fail_drop;
+
+	/* inherit flags from parent */
+	jfs_inode->mode2 = JFS_IP(parent)->mode2 & JFS_FL_INHERIT;
+
+	if (S_ISDIR(mode)) {
+		jfs_inode->mode2 |= IDIRECTORY;
+		jfs_inode->mode2 &= ~JFS_DIRSYNC_FL;
+	}
+	else {
+		jfs_inode->mode2 |= INLINEEA | ISPARSE;
+		if (S_ISLNK(mode))
+			jfs_inode->mode2 &= ~(JFS_IMMUTABLE_FL|JFS_APPEND_FL);
+	}
+	jfs_inode->mode2 |= inode->i_mode;
+
+	inode->i_blocks = 0;
+	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
+	jfs_inode->otime = inode->i_ctime.tv_sec;
+	inode->i_generation = JFS_SBI(sb)->gengen++;
+
+	jfs_inode->cflag = 0;
+
+	/* Zero remaining fields */
+	memset(&jfs_inode->acl, 0, sizeof(dxd_t));
+	memset(&jfs_inode->ea, 0, sizeof(dxd_t));
+	jfs_inode->next_index = 0;
+	jfs_inode->acltype = 0;
+	jfs_inode->btorder = 0;
+	jfs_inode->btindex = 0;
+	jfs_inode->bxflag = 0;
+	jfs_inode->blid = 0;
+	jfs_inode->atlhead = 0;
+	jfs_inode->atltail = 0;
+	jfs_inode->xtlid = 0;
+	jfs_set_inode_flags(inode);
+
+	jfs_info("ialloc returns inode = 0x%p", inode);
+
+	return inode;
+
+fail_drop:
+	dquot_drop(inode);
+	inode->i_flags |= S_NOQUOTA;
+	clear_nlink(inode);
+	discard_new_inode(inode);
+	return ERR_PTR(rc);
+
+fail_put:
+	iput(inode);
+	return ERR_PTR(rc);
+}
diff --git a/fs/jfs/jfs_inode.h b/fs/jfs/jfs_inode.h
new file mode 100644
index 000000000..7de961a81
--- /dev/null
+++ b/fs/jfs/jfs_inode.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2001
+ */
+#ifndef	_H_JFS_INODE
+#define _H_JFS_INODE
+
+struct fid;
+
+extern struct inode *ialloc(struct inode *, umode_t);
+extern int jfs_fsync(struct file *, loff_t, loff_t, int);
+extern int jfs_fileattr_get(struct dentry *dentry, struct fileattr *fa);
+extern int jfs_fileattr_set(struct user_namespace *mnt_userns,
+			    struct dentry *dentry, struct fileattr *fa);
+extern long jfs_ioctl(struct file *, unsigned int, unsigned long);
+extern struct inode *jfs_iget(struct super_block *, unsigned long);
+extern int jfs_commit_inode(struct inode *, int);
+extern int jfs_write_inode(struct inode *, struct writeback_control *);
+extern void jfs_evict_inode(struct inode *);
+extern void jfs_dirty_inode(struct inode *, int);
+extern void jfs_truncate(struct inode *);
+extern void jfs_truncate_nolock(struct inode *, loff_t);
+extern void jfs_free_zero_link(struct inode *);
+extern struct dentry *jfs_get_parent(struct dentry *dentry);
+extern struct dentry *jfs_fh_to_dentry(struct super_block *sb, struct fid *fid,
+	int fh_len, int fh_type);
+extern struct dentry *jfs_fh_to_parent(struct super_block *sb, struct fid *fid,
+	int fh_len, int fh_type);
+extern void jfs_set_inode_flags(struct inode *);
+extern int jfs_get_block(struct inode *, sector_t, struct buffer_head *, int);
+extern int jfs_setattr(struct user_namespace *, struct dentry *, struct iattr *);
+
+extern const struct address_space_operations jfs_aops;
+extern const struct inode_operations jfs_dir_inode_operations;
+extern const struct file_operations jfs_dir_operations;
+extern const struct inode_operations jfs_file_inode_operations;
+extern const struct file_operations jfs_file_operations;
+extern const struct inode_operations jfs_symlink_inode_operations;
+extern const struct inode_operations jfs_fast_symlink_inode_operations;
+extern const struct dentry_operations jfs_ci_dentry_operations;
+#endif				/* _H_JFS_INODE */
diff --git a/fs/jfs/jfs_lock.h b/fs/jfs/jfs_lock.h
new file mode 100644
index 000000000..feb37dd9d
--- /dev/null
+++ b/fs/jfs/jfs_lock.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2001
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+#ifndef _H_JFS_LOCK
+#define _H_JFS_LOCK
+
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+
+/*
+ *	jfs_lock.h
+ */
+
+/*
+ * Conditional sleep where condition is protected by spinlock
+ *
+ * lock_cmd and unlock_cmd take and release the spinlock
+ */
+#define __SLEEP_COND(wq, cond, lock_cmd, unlock_cmd)	\
+do {							\
+	DECLARE_WAITQUEUE(__wait, current);		\
+							\
+	add_wait_queue(&wq, &__wait);			\
+	for (;;) {					\
+		set_current_state(TASK_UNINTERRUPTIBLE);\
+		if (cond)				\
+			break;				\
+		unlock_cmd;				\
+		io_schedule();				\
+		lock_cmd;				\
+	}						\
+	__set_current_state(TASK_RUNNING);			\
+	remove_wait_queue(&wq, &__wait);		\
+} while (0)
+
+#endif				/* _H_JFS_LOCK */
diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c
new file mode 100644
index 000000000..695415cbf
--- /dev/null
+++ b/fs/jfs/jfs_logmgr.c
@@ -0,0 +1,2486 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+/*
+ *	jfs_logmgr.c: log manager
+ *
+ * for related information, see transaction manager (jfs_txnmgr.c), and
+ * recovery manager (jfs_logredo.c).
+ *
+ * note: for detail, RTFS.
+ *
+ *	log buffer manager:
+ * special purpose buffer manager supporting log i/o requirements.
+ * per log serial pageout of logpage
+ * queuing i/o requests and redrive i/o at iodone
+ * maintain current logpage buffer
+ * no caching since append only
+ * appropriate jfs buffer cache buffers as needed
+ *
+ *	group commit:
+ * transactions which wrote COMMIT records in the same in-memory
+ * log page during the pageout of previous/current log page(s) are
+ * committed together by the pageout of the page.
+ *
+ *	TBD lazy commit:
+ * transactions are committed asynchronously when the log page
+ * containing it COMMIT is paged out when it becomes full;
+ *
+ *	serialization:
+ * . a per log lock serialize log write.
+ * . a per log lock serialize group commit.
+ * . a per log lock serialize log open/close;
+ *
+ *	TBD log integrity:
+ * careful-write (ping-pong) of last logpage to recover from crash
+ * in overwrite.
+ * detection of split (out-of-order) write of physical sectors
+ * of last logpage via timestamp at end of each sector
+ * with its mirror data array at trailer).
+ *
+ *	alternatives:
+ * lsn - 64-bit monotonically increasing integer vs
+ * 32-bit lspn and page eor.
+ */
+
+#include <linux/fs.h>
+#include <linux/blkdev.h>
+#include <linux/interrupt.h>
+#include <linux/completion.h>
+#include <linux/kthread.h>
+#include <linux/buffer_head.h>		/* for sync_blockdev() */
+#include <linux/bio.h>
+#include <linux/freezer.h>
+#include <linux/export.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_metapage.h"
+#include "jfs_superblock.h"
+#include "jfs_txnmgr.h"
+#include "jfs_debug.h"
+
+
+/*
+ * lbuf's ready to be redriven.  Protected by log_redrive_lock (jfsIO thread)
+ */
+static struct lbuf *log_redrive_list;
+static DEFINE_SPINLOCK(log_redrive_lock);
+
+
+/*
+ *	log read/write serialization (per log)
+ */
+#define LOG_LOCK_INIT(log)	mutex_init(&(log)->loglock)
+#define LOG_LOCK(log)		mutex_lock(&((log)->loglock))
+#define LOG_UNLOCK(log)		mutex_unlock(&((log)->loglock))
+
+
+/*
+ *	log group commit serialization (per log)
+ */
+
+#define LOGGC_LOCK_INIT(log)	spin_lock_init(&(log)->gclock)
+#define LOGGC_LOCK(log)		spin_lock_irq(&(log)->gclock)
+#define LOGGC_UNLOCK(log)	spin_unlock_irq(&(log)->gclock)
+#define LOGGC_WAKEUP(tblk)	wake_up_all(&(tblk)->gcwait)
+
+/*
+ *	log sync serialization (per log)
+ */
+#define	LOGSYNC_DELTA(logsize)		min((logsize)/8, 128*LOGPSIZE)
+#define	LOGSYNC_BARRIER(logsize)	((logsize)/4)
+/*
+#define	LOGSYNC_DELTA(logsize)		min((logsize)/4, 256*LOGPSIZE)
+#define	LOGSYNC_BARRIER(logsize)	((logsize)/2)
+*/
+
+
+/*
+ *	log buffer cache synchronization
+ */
+static DEFINE_SPINLOCK(jfsLCacheLock);
+
+#define	LCACHE_LOCK(flags)	spin_lock_irqsave(&jfsLCacheLock, flags)
+#define	LCACHE_UNLOCK(flags)	spin_unlock_irqrestore(&jfsLCacheLock, flags)
+
+/*
+ * See __SLEEP_COND in jfs_locks.h
+ */
+#define LCACHE_SLEEP_COND(wq, cond, flags)	\
+do {						\
+	if (cond)				\
+		break;				\
+	__SLEEP_COND(wq, cond, LCACHE_LOCK(flags), LCACHE_UNLOCK(flags)); \
+} while (0)
+
+#define	LCACHE_WAKEUP(event)	wake_up(event)
+
+
+/*
+ *	lbuf buffer cache (lCache) control
+ */
+/* log buffer manager pageout control (cumulative, inclusive) */
+#define	lbmREAD		0x0001
+#define	lbmWRITE	0x0002	/* enqueue at tail of write queue;
+				 * init pageout if at head of queue;
+				 */
+#define	lbmRELEASE	0x0004	/* remove from write queue
+				 * at completion of pageout;
+				 * do not free/recycle it yet:
+				 * caller will free it;
+				 */
+#define	lbmSYNC		0x0008	/* do not return to freelist
+				 * when removed from write queue;
+				 */
+#define lbmFREE		0x0010	/* return to freelist
+				 * at completion of pageout;
+				 * the buffer may be recycled;
+				 */
+#define	lbmDONE		0x0020
+#define	lbmERROR	0x0040
+#define lbmGC		0x0080	/* lbmIODone to perform post-GC processing
+				 * of log page
+				 */
+#define lbmDIRECT	0x0100
+
+/*
+ * Global list of active external journals
+ */
+static LIST_HEAD(jfs_external_logs);
+static struct jfs_log *dummy_log;
+static DEFINE_MUTEX(jfs_log_mutex);
+
+/*
+ * forward references
+ */
+static int lmWriteRecord(struct jfs_log * log, struct tblock * tblk,
+			 struct lrd * lrd, struct tlock * tlck);
+
+static int lmNextPage(struct jfs_log * log);
+static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
+			   int activate);
+
+static int open_inline_log(struct super_block *sb);
+static int open_dummy_log(struct super_block *sb);
+static int lbmLogInit(struct jfs_log * log);
+static void lbmLogShutdown(struct jfs_log * log);
+static struct lbuf *lbmAllocate(struct jfs_log * log, int);
+static void lbmFree(struct lbuf * bp);
+static void lbmfree(struct lbuf * bp);
+static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp);
+static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag, int cant_block);
+static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag);
+static int lbmIOWait(struct lbuf * bp, int flag);
+static bio_end_io_t lbmIODone;
+static void lbmStartIO(struct lbuf * bp);
+static void lmGCwrite(struct jfs_log * log, int cant_block);
+static int lmLogSync(struct jfs_log * log, int hard_sync);
+
+
+
+/*
+ *	statistics
+ */
+#ifdef CONFIG_JFS_STATISTICS
+static struct lmStat {
+	uint commit;		/* # of commit */
+	uint pagedone;		/* # of page written */
+	uint submitted;		/* # of pages submitted */
+	uint full_page;		/* # of full pages submitted */
+	uint partial_page;	/* # of partial pages submitted */
+} lmStat;
+#endif
+
+static void write_special_inodes(struct jfs_log *log,
+				 int (*writer)(struct address_space *))
+{
+	struct jfs_sb_info *sbi;
+
+	list_for_each_entry(sbi, &log->sb_list, log_list) {
+		writer(sbi->ipbmap->i_mapping);
+		writer(sbi->ipimap->i_mapping);
+		writer(sbi->direct_inode->i_mapping);
+	}
+}
+
+/*
+ * NAME:	lmLog()
+ *
+ * FUNCTION:	write a log record;
+ *
+ * PARAMETER:
+ *
+ * RETURN:	lsn - offset to the next log record to write (end-of-log);
+ *		-1  - error;
+ *
+ * note: todo: log error handler
+ */
+int lmLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
+	  struct tlock * tlck)
+{
+	int lsn;
+	int diffp, difft;
+	struct metapage *mp = NULL;
+	unsigned long flags;
+
+	jfs_info("lmLog: log:0x%p tblk:0x%p, lrd:0x%p tlck:0x%p",
+		 log, tblk, lrd, tlck);
+
+	LOG_LOCK(log);
+
+	/* log by (out-of-transaction) JFS ? */
+	if (tblk == NULL)
+		goto writeRecord;
+
+	/* log from page ? */
+	if (tlck == NULL ||
+	    tlck->type & tlckBTROOT || (mp = tlck->mp) == NULL)
+		goto writeRecord;
+
+	/*
+	 *	initialize/update page/transaction recovery lsn
+	 */
+	lsn = log->lsn;
+
+	LOGSYNC_LOCK(log, flags);
+
+	/*
+	 * initialize page lsn if first log write of the page
+	 */
+	if (mp->lsn == 0) {
+		mp->log = log;
+		mp->lsn = lsn;
+		log->count++;
+
+		/* insert page at tail of logsynclist */
+		list_add_tail(&mp->synclist, &log->synclist);
+	}
+
+	/*
+	 *	initialize/update lsn of tblock of the page
+	 *
+	 * transaction inherits oldest lsn of pages associated
+	 * with allocation/deallocation of resources (their
+	 * log records are used to reconstruct allocation map
+	 * at recovery time: inode for inode allocation map,
+	 * B+-tree index of extent descriptors for block
+	 * allocation map);
+	 * allocation map pages inherit transaction lsn at
+	 * commit time to allow forwarding log syncpt past log
+	 * records associated with allocation/deallocation of
+	 * resources only after persistent map of these map pages
+	 * have been updated and propagated to home.
+	 */
+	/*
+	 * initialize transaction lsn:
+	 */
+	if (tblk->lsn == 0) {
+		/* inherit lsn of its first page logged */
+		tblk->lsn = mp->lsn;
+		log->count++;
+
+		/* insert tblock after the page on logsynclist */
+		list_add(&tblk->synclist, &mp->synclist);
+	}
+	/*
+	 * update transaction lsn:
+	 */
+	else {
+		/* inherit oldest/smallest lsn of page */
+		logdiff(diffp, mp->lsn, log);
+		logdiff(difft, tblk->lsn, log);
+		if (diffp < difft) {
+			/* update tblock lsn with page lsn */
+			tblk->lsn = mp->lsn;
+
+			/* move tblock after page on logsynclist */
+			list_move(&tblk->synclist, &mp->synclist);
+		}
+	}
+
+	LOGSYNC_UNLOCK(log, flags);
+
+	/*
+	 *	write the log record
+	 */
+      writeRecord:
+	lsn = lmWriteRecord(log, tblk, lrd, tlck);
+
+	/*
+	 * forward log syncpt if log reached next syncpt trigger
+	 */
+	logdiff(diffp, lsn, log);
+	if (diffp >= log->nextsync)
+		lsn = lmLogSync(log, 0);
+
+	/* update end-of-log lsn */
+	log->lsn = lsn;
+
+	LOG_UNLOCK(log);
+
+	/* return end-of-log address */
+	return lsn;
+}
+
+/*
+ * NAME:	lmWriteRecord()
+ *
+ * FUNCTION:	move the log record to current log page
+ *
+ * PARAMETER:	cd	- commit descriptor
+ *
+ * RETURN:	end-of-log address
+ *
+ * serialization: LOG_LOCK() held on entry/exit
+ */
+static int
+lmWriteRecord(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
+	      struct tlock * tlck)
+{
+	int lsn = 0;		/* end-of-log address */
+	struct lbuf *bp;	/* dst log page buffer */
+	struct logpage *lp;	/* dst log page */
+	caddr_t dst;		/* destination address in log page */
+	int dstoffset;		/* end-of-log offset in log page */
+	int freespace;		/* free space in log page */
+	caddr_t p;		/* src meta-data page */
+	caddr_t src;
+	int srclen;
+	int nbytes;		/* number of bytes to move */
+	int i;
+	int len;
+	struct linelock *linelock;
+	struct lv *lv;
+	struct lvd *lvd;
+	int l2linesize;
+
+	len = 0;
+
+	/* retrieve destination log page to write */
+	bp = (struct lbuf *) log->bp;
+	lp = (struct logpage *) bp->l_ldata;
+	dstoffset = log->eor;
+
+	/* any log data to write ? */
+	if (tlck == NULL)
+		goto moveLrd;
+
+	/*
+	 *	move log record data
+	 */
+	/* retrieve source meta-data page to log */
+	if (tlck->flag & tlckPAGELOCK) {
+		p = (caddr_t) (tlck->mp->data);
+		linelock = (struct linelock *) & tlck->lock;
+	}
+	/* retrieve source in-memory inode to log */
+	else if (tlck->flag & tlckINODELOCK) {
+		if (tlck->type & tlckDTREE)
+			p = (caddr_t) &JFS_IP(tlck->ip)->i_dtroot;
+		else
+			p = (caddr_t) &JFS_IP(tlck->ip)->i_xtroot;
+		linelock = (struct linelock *) & tlck->lock;
+	}
+	else {
+		jfs_err("lmWriteRecord: UFO tlck:0x%p", tlck);
+		return 0;	/* Probably should trap */
+	}
+	l2linesize = linelock->l2linesize;
+
+      moveData:
+	ASSERT(linelock->index <= linelock->maxcnt);
+
+	lv = linelock->lv;
+	for (i = 0; i < linelock->index; i++, lv++) {
+		if (lv->length == 0)
+			continue;
+
+		/* is page full ? */
+		if (dstoffset >= LOGPSIZE - LOGPTLRSIZE) {
+			/* page become full: move on to next page */
+			lmNextPage(log);
+
+			bp = log->bp;
+			lp = (struct logpage *) bp->l_ldata;
+			dstoffset = LOGPHDRSIZE;
+		}
+
+		/*
+		 * move log vector data
+		 */
+		src = (u8 *) p + (lv->offset << l2linesize);
+		srclen = lv->length << l2linesize;
+		len += srclen;
+		while (srclen > 0) {
+			freespace = (LOGPSIZE - LOGPTLRSIZE) - dstoffset;
+			nbytes = min(freespace, srclen);
+			dst = (caddr_t) lp + dstoffset;
+			memcpy(dst, src, nbytes);
+			dstoffset += nbytes;
+
+			/* is page not full ? */
+			if (dstoffset < LOGPSIZE - LOGPTLRSIZE)
+				break;
+
+			/* page become full: move on to next page */
+			lmNextPage(log);
+
+			bp = (struct lbuf *) log->bp;
+			lp = (struct logpage *) bp->l_ldata;
+			dstoffset = LOGPHDRSIZE;
+
+			srclen -= nbytes;
+			src += nbytes;
+		}
+
+		/*
+		 * move log vector descriptor
+		 */
+		len += 4;
+		lvd = (struct lvd *) ((caddr_t) lp + dstoffset);
+		lvd->offset = cpu_to_le16(lv->offset);
+		lvd->length = cpu_to_le16(lv->length);
+		dstoffset += 4;
+		jfs_info("lmWriteRecord: lv offset:%d length:%d",
+			 lv->offset, lv->length);
+	}
+
+	if ((i = linelock->next)) {
+		linelock = (struct linelock *) lid_to_tlock(i);
+		goto moveData;
+	}
+
+	/*
+	 *	move log record descriptor
+	 */
+      moveLrd:
+	lrd->length = cpu_to_le16(len);
+
+	src = (caddr_t) lrd;
+	srclen = LOGRDSIZE;
+
+	while (srclen > 0) {
+		freespace = (LOGPSIZE - LOGPTLRSIZE) - dstoffset;
+		nbytes = min(freespace, srclen);
+		dst = (caddr_t) lp + dstoffset;
+		memcpy(dst, src, nbytes);
+
+		dstoffset += nbytes;
+		srclen -= nbytes;
+
+		/* are there more to move than freespace of page ? */
+		if (srclen)
+			goto pageFull;
+
+		/*
+		 * end of log record descriptor
+		 */
+
+		/* update last log record eor */
+		log->eor = dstoffset;
+		bp->l_eor = dstoffset;
+		lsn = (log->page << L2LOGPSIZE) + dstoffset;
+
+		if (lrd->type & cpu_to_le16(LOG_COMMIT)) {
+			tblk->clsn = lsn;
+			jfs_info("wr: tclsn:0x%x, beor:0x%x", tblk->clsn,
+				 bp->l_eor);
+
+			INCREMENT(lmStat.commit);	/* # of commit */
+
+			/*
+			 * enqueue tblock for group commit:
+			 *
+			 * enqueue tblock of non-trivial/synchronous COMMIT
+			 * at tail of group commit queue
+			 * (trivial/asynchronous COMMITs are ignored by
+			 * group commit.)
+			 */
+			LOGGC_LOCK(log);
+
+			/* init tblock gc state */
+			tblk->flag = tblkGC_QUEUE;
+			tblk->bp = log->bp;
+			tblk->pn = log->page;
+			tblk->eor = log->eor;
+
+			/* enqueue transaction to commit queue */
+			list_add_tail(&tblk->cqueue, &log->cqueue);
+
+			LOGGC_UNLOCK(log);
+		}
+
+		jfs_info("lmWriteRecord: lrd:0x%04x bp:0x%p pn:%d eor:0x%x",
+			le16_to_cpu(lrd->type), log->bp, log->page, dstoffset);
+
+		/* page not full ? */
+		if (dstoffset < LOGPSIZE - LOGPTLRSIZE)
+			return lsn;
+
+	      pageFull:
+		/* page become full: move on to next page */
+		lmNextPage(log);
+
+		bp = (struct lbuf *) log->bp;
+		lp = (struct logpage *) bp->l_ldata;
+		dstoffset = LOGPHDRSIZE;
+		src += nbytes;
+	}
+
+	return lsn;
+}
+
+
+/*
+ * NAME:	lmNextPage()
+ *
+ * FUNCTION:	write current page and allocate next page.
+ *
+ * PARAMETER:	log
+ *
+ * RETURN:	0
+ *
+ * serialization: LOG_LOCK() held on entry/exit
+ */
+static int lmNextPage(struct jfs_log * log)
+{
+	struct logpage *lp;
+	int lspn;		/* log sequence page number */
+	int pn;			/* current page number */
+	struct lbuf *bp;
+	struct lbuf *nextbp;
+	struct tblock *tblk;
+
+	/* get current log page number and log sequence page number */
+	pn = log->page;
+	bp = log->bp;
+	lp = (struct logpage *) bp->l_ldata;
+	lspn = le32_to_cpu(lp->h.page);
+
+	LOGGC_LOCK(log);
+
+	/*
+	 *	write or queue the full page at the tail of write queue
+	 */
+	/* get the tail tblk on commit queue */
+	if (list_empty(&log->cqueue))
+		tblk = NULL;
+	else
+		tblk = list_entry(log->cqueue.prev, struct tblock, cqueue);
+
+	/* every tblk who has COMMIT record on the current page,
+	 * and has not been committed, must be on commit queue
+	 * since tblk is queued at commit queueu at the time
+	 * of writing its COMMIT record on the page before
+	 * page becomes full (even though the tblk thread
+	 * who wrote COMMIT record may have been suspended
+	 * currently);
+	 */
+
+	/* is page bound with outstanding tail tblk ? */
+	if (tblk && tblk->pn == pn) {
+		/* mark tblk for end-of-page */
+		tblk->flag |= tblkGC_EOP;
+
+		if (log->cflag & logGC_PAGEOUT) {
+			/* if page is not already on write queue,
+			 * just enqueue (no lbmWRITE to prevent redrive)
+			 * buffer to wqueue to ensure correct serial order
+			 * of the pages since log pages will be added
+			 * continuously
+			 */
+			if (bp->l_wqnext == NULL)
+				lbmWrite(log, bp, 0, 0);
+		} else {
+			/*
+			 * No current GC leader, initiate group commit
+			 */
+			log->cflag |= logGC_PAGEOUT;
+			lmGCwrite(log, 0);
+		}
+	}
+	/* page is not bound with outstanding tblk:
+	 * init write or mark it to be redriven (lbmWRITE)
+	 */
+	else {
+		/* finalize the page */
+		bp->l_ceor = bp->l_eor;
+		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
+		lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmFREE, 0);
+	}
+	LOGGC_UNLOCK(log);
+
+	/*
+	 *	allocate/initialize next page
+	 */
+	/* if log wraps, the first data page of log is 2
+	 * (0 never used, 1 is superblock).
+	 */
+	log->page = (pn == log->size - 1) ? 2 : pn + 1;
+	log->eor = LOGPHDRSIZE;	/* ? valid page empty/full at logRedo() */
+
+	/* allocate/initialize next log page buffer */
+	nextbp = lbmAllocate(log, log->page);
+	nextbp->l_eor = log->eor;
+	log->bp = nextbp;
+
+	/* initialize next log page */
+	lp = (struct logpage *) nextbp->l_ldata;
+	lp->h.page = lp->t.page = cpu_to_le32(lspn + 1);
+	lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
+
+	return 0;
+}
+
+
+/*
+ * NAME:	lmGroupCommit()
+ *
+ * FUNCTION:	group commit
+ *	initiate pageout of the pages with COMMIT in the order of
+ *	page number - redrive pageout of the page at the head of
+ *	pageout queue until full page has been written.
+ *
+ * RETURN:
+ *
+ * NOTE:
+ *	LOGGC_LOCK serializes log group commit queue, and
+ *	transaction blocks on the commit queue.
+ *	N.B. LOG_LOCK is NOT held during lmGroupCommit().
+ */
+int lmGroupCommit(struct jfs_log * log, struct tblock * tblk)
+{
+	int rc = 0;
+
+	LOGGC_LOCK(log);
+
+	/* group committed already ? */
+	if (tblk->flag & tblkGC_COMMITTED) {
+		if (tblk->flag & tblkGC_ERROR)
+			rc = -EIO;
+
+		LOGGC_UNLOCK(log);
+		return rc;
+	}
+	jfs_info("lmGroup Commit: tblk = 0x%p, gcrtc = %d", tblk, log->gcrtc);
+
+	if (tblk->xflag & COMMIT_LAZY)
+		tblk->flag |= tblkGC_LAZY;
+
+	if ((!(log->cflag & logGC_PAGEOUT)) && (!list_empty(&log->cqueue)) &&
+	    (!(tblk->xflag & COMMIT_LAZY) || test_bit(log_FLUSH, &log->flag)
+	     || jfs_tlocks_low)) {
+		/*
+		 * No pageout in progress
+		 *
+		 * start group commit as its group leader.
+		 */
+		log->cflag |= logGC_PAGEOUT;
+
+		lmGCwrite(log, 0);
+	}
+
+	if (tblk->xflag & COMMIT_LAZY) {
+		/*
+		 * Lazy transactions can leave now
+		 */
+		LOGGC_UNLOCK(log);
+		return 0;
+	}
+
+	/* lmGCwrite gives up LOGGC_LOCK, check again */
+
+	if (tblk->flag & tblkGC_COMMITTED) {
+		if (tblk->flag & tblkGC_ERROR)
+			rc = -EIO;
+
+		LOGGC_UNLOCK(log);
+		return rc;
+	}
+
+	/* upcount transaction waiting for completion
+	 */
+	log->gcrtc++;
+	tblk->flag |= tblkGC_READY;
+
+	__SLEEP_COND(tblk->gcwait, (tblk->flag & tblkGC_COMMITTED),
+		     LOGGC_LOCK(log), LOGGC_UNLOCK(log));
+
+	/* removed from commit queue */
+	if (tblk->flag & tblkGC_ERROR)
+		rc = -EIO;
+
+	LOGGC_UNLOCK(log);
+	return rc;
+}
+
+/*
+ * NAME:	lmGCwrite()
+ *
+ * FUNCTION:	group commit write
+ *	initiate write of log page, building a group of all transactions
+ *	with commit records on that page.
+ *
+ * RETURN:	None
+ *
+ * NOTE:
+ *	LOGGC_LOCK must be held by caller.
+ *	N.B. LOG_LOCK is NOT held during lmGroupCommit().
+ */
+static void lmGCwrite(struct jfs_log * log, int cant_write)
+{
+	struct lbuf *bp;
+	struct logpage *lp;
+	int gcpn;		/* group commit page number */
+	struct tblock *tblk;
+	struct tblock *xtblk = NULL;
+
+	/*
+	 * build the commit group of a log page
+	 *
+	 * scan commit queue and make a commit group of all
+	 * transactions with COMMIT records on the same log page.
+	 */
+	/* get the head tblk on the commit queue */
+	gcpn = list_entry(log->cqueue.next, struct tblock, cqueue)->pn;
+
+	list_for_each_entry(tblk, &log->cqueue, cqueue) {
+		if (tblk->pn != gcpn)
+			break;
+
+		xtblk = tblk;
+
+		/* state transition: (QUEUE, READY) -> COMMIT */
+		tblk->flag |= tblkGC_COMMIT;
+	}
+	tblk = xtblk;		/* last tblk of the page */
+
+	/*
+	 * pageout to commit transactions on the log page.
+	 */
+	bp = (struct lbuf *) tblk->bp;
+	lp = (struct logpage *) bp->l_ldata;
+	/* is page already full ? */
+	if (tblk->flag & tblkGC_EOP) {
+		/* mark page to free at end of group commit of the page */
+		tblk->flag &= ~tblkGC_EOP;
+		tblk->flag |= tblkGC_FREE;
+		bp->l_ceor = bp->l_eor;
+		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
+		lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmGC,
+			 cant_write);
+		INCREMENT(lmStat.full_page);
+	}
+	/* page is not yet full */
+	else {
+		bp->l_ceor = tblk->eor;	/* ? bp->l_ceor = bp->l_eor; */
+		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
+		lbmWrite(log, bp, lbmWRITE | lbmGC, cant_write);
+		INCREMENT(lmStat.partial_page);
+	}
+}
+
+/*
+ * NAME:	lmPostGC()
+ *
+ * FUNCTION:	group commit post-processing
+ *	Processes transactions after their commit records have been written
+ *	to disk, redriving log I/O if necessary.
+ *
+ * RETURN:	None
+ *
+ * NOTE:
+ *	This routine is called a interrupt time by lbmIODone
+ */
+static void lmPostGC(struct lbuf * bp)
+{
+	unsigned long flags;
+	struct jfs_log *log = bp->l_log;
+	struct logpage *lp;
+	struct tblock *tblk, *temp;
+
+	//LOGGC_LOCK(log);
+	spin_lock_irqsave(&log->gclock, flags);
+	/*
+	 * current pageout of group commit completed.
+	 *
+	 * remove/wakeup transactions from commit queue who were
+	 * group committed with the current log page
+	 */
+	list_for_each_entry_safe(tblk, temp, &log->cqueue, cqueue) {
+		if (!(tblk->flag & tblkGC_COMMIT))
+			break;
+		/* if transaction was marked GC_COMMIT then
+		 * it has been shipped in the current pageout
+		 * and made it to disk - it is committed.
+		 */
+
+		if (bp->l_flag & lbmERROR)
+			tblk->flag |= tblkGC_ERROR;
+
+		/* remove it from the commit queue */
+		list_del(&tblk->cqueue);
+		tblk->flag &= ~tblkGC_QUEUE;
+
+		if (tblk == log->flush_tblk) {
+			/* we can stop flushing the log now */
+			clear_bit(log_FLUSH, &log->flag);
+			log->flush_tblk = NULL;
+		}
+
+		jfs_info("lmPostGC: tblk = 0x%p, flag = 0x%x", tblk,
+			 tblk->flag);
+
+		if (!(tblk->xflag & COMMIT_FORCE))
+			/*
+			 * Hand tblk over to lazy commit thread
+			 */
+			txLazyUnlock(tblk);
+		else {
+			/* state transition: COMMIT -> COMMITTED */
+			tblk->flag |= tblkGC_COMMITTED;
+
+			if (tblk->flag & tblkGC_READY)
+				log->gcrtc--;
+
+			LOGGC_WAKEUP(tblk);
+		}
+
+		/* was page full before pageout ?
+		 * (and this is the last tblk bound with the page)
+		 */
+		if (tblk->flag & tblkGC_FREE)
+			lbmFree(bp);
+		/* did page become full after pageout ?
+		 * (and this is the last tblk bound with the page)
+		 */
+		else if (tblk->flag & tblkGC_EOP) {
+			/* finalize the page */
+			lp = (struct logpage *) bp->l_ldata;
+			bp->l_ceor = bp->l_eor;
+			lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
+			jfs_info("lmPostGC: calling lbmWrite");
+			lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmFREE,
+				 1);
+		}
+
+	}
+
+	/* are there any transactions who have entered lnGroupCommit()
+	 * (whose COMMITs are after that of the last log page written.
+	 * They are waiting for new group commit (above at (SLEEP 1))
+	 * or lazy transactions are on a full (queued) log page,
+	 * select the latest ready transaction as new group leader and
+	 * wake her up to lead her group.
+	 */
+	if ((!list_empty(&log->cqueue)) &&
+	    ((log->gcrtc > 0) || (tblk->bp->l_wqnext != NULL) ||
+	     test_bit(log_FLUSH, &log->flag) || jfs_tlocks_low))
+		/*
+		 * Call lmGCwrite with new group leader
+		 */
+		lmGCwrite(log, 1);
+
+	/* no transaction are ready yet (transactions are only just
+	 * queued (GC_QUEUE) and not entered for group commit yet).
+	 * the first transaction entering group commit
+	 * will elect herself as new group leader.
+	 */
+	else
+		log->cflag &= ~logGC_PAGEOUT;
+
+	//LOGGC_UNLOCK(log);
+	spin_unlock_irqrestore(&log->gclock, flags);
+	return;
+}
+
+/*
+ * NAME:	lmLogSync()
+ *
+ * FUNCTION:	write log SYNCPT record for specified log
+ *	if new sync address is available
+ *	(normally the case if sync() is executed by back-ground
+ *	process).
+ *	calculate new value of i_nextsync which determines when
+ *	this code is called again.
+ *
+ * PARAMETERS:	log	- log structure
+ *		hard_sync - 1 to force all metadata to be written
+ *
+ * RETURN:	0
+ *
+ * serialization: LOG_LOCK() held on entry/exit
+ */
+static int lmLogSync(struct jfs_log * log, int hard_sync)
+{
+	int logsize;
+	int written;		/* written since last syncpt */
+	int free;		/* free space left available */
+	int delta;		/* additional delta to write normally */
+	int more;		/* additional write granted */
+	struct lrd lrd;
+	int lsn;
+	struct logsyncblk *lp;
+	unsigned long flags;
+
+	/* push dirty metapages out to disk */
+	if (hard_sync)
+		write_special_inodes(log, filemap_fdatawrite);
+	else
+		write_special_inodes(log, filemap_flush);
+
+	/*
+	 *	forward syncpt
+	 */
+	/* if last sync is same as last syncpt,
+	 * invoke sync point forward processing to update sync.
+	 */
+
+	if (log->sync == log->syncpt) {
+		LOGSYNC_LOCK(log, flags);
+		if (list_empty(&log->synclist))
+			log->sync = log->lsn;
+		else {
+			lp = list_entry(log->synclist.next,
+					struct logsyncblk, synclist);
+			log->sync = lp->lsn;
+		}
+		LOGSYNC_UNLOCK(log, flags);
+
+	}
+
+	/* if sync is different from last syncpt,
+	 * write a SYNCPT record with syncpt = sync.
+	 * reset syncpt = sync
+	 */
+	if (log->sync != log->syncpt) {
+		lrd.logtid = 0;
+		lrd.backchain = 0;
+		lrd.type = cpu_to_le16(LOG_SYNCPT);
+		lrd.length = 0;
+		lrd.log.syncpt.sync = cpu_to_le32(log->sync);
+		lsn = lmWriteRecord(log, NULL, &lrd, NULL);
+
+		log->syncpt = log->sync;
+	} else
+		lsn = log->lsn;
+
+	/*
+	 *	setup next syncpt trigger (SWAG)
+	 */
+	logsize = log->logsize;
+
+	logdiff(written, lsn, log);
+	free = logsize - written;
+	delta = LOGSYNC_DELTA(logsize);
+	more = min(free / 2, delta);
+	if (more < 2 * LOGPSIZE) {
+		jfs_warn("\n ... Log Wrap ... Log Wrap ... Log Wrap ...\n");
+		/*
+		 *	log wrapping
+		 *
+		 * option 1 - panic ? No.!
+		 * option 2 - shutdown file systems
+		 *	      associated with log ?
+		 * option 3 - extend log ?
+		 * option 4 - second chance
+		 *
+		 * mark log wrapped, and continue.
+		 * when all active transactions are completed,
+		 * mark log valid for recovery.
+		 * if crashed during invalid state, log state
+		 * implies invalid log, forcing fsck().
+		 */
+		/* mark log state log wrap in log superblock */
+		/* log->state = LOGWRAP; */
+
+		/* reset sync point computation */
+		log->syncpt = log->sync = lsn;
+		log->nextsync = delta;
+	} else
+		/* next syncpt trigger = written + more */
+		log->nextsync = written + more;
+
+	/* if number of bytes written from last sync point is more
+	 * than 1/4 of the log size, stop new transactions from
+	 * starting until all current transactions are completed
+	 * by setting syncbarrier flag.
+	 */
+	if (!test_bit(log_SYNCBARRIER, &log->flag) &&
+	    (written > LOGSYNC_BARRIER(logsize)) && log->active) {
+		set_bit(log_SYNCBARRIER, &log->flag);
+		jfs_info("log barrier on: lsn=0x%x syncpt=0x%x", lsn,
+			 log->syncpt);
+		/*
+		 * We may have to initiate group commit
+		 */
+		jfs_flush_journal(log, 0);
+	}
+
+	return lsn;
+}
+
+/*
+ * NAME:	jfs_syncpt
+ *
+ * FUNCTION:	write log SYNCPT record for specified log
+ *
+ * PARAMETERS:	log	  - log structure
+ *		hard_sync - set to 1 to force metadata to be written
+ */
+void jfs_syncpt(struct jfs_log *log, int hard_sync)
+{	LOG_LOCK(log);
+	if (!test_bit(log_QUIESCE, &log->flag))
+		lmLogSync(log, hard_sync);
+	LOG_UNLOCK(log);
+}
+
+/*
+ * NAME:	lmLogOpen()
+ *
+ * FUNCTION:	open the log on first open;
+ *	insert filesystem in the active list of the log.
+ *
+ * PARAMETER:	ipmnt	- file system mount inode
+ *		iplog	- log inode (out)
+ *
+ * RETURN:
+ *
+ * serialization:
+ */
+int lmLogOpen(struct super_block *sb)
+{
+	int rc;
+	struct block_device *bdev;
+	struct jfs_log *log;
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+
+	if (sbi->flag & JFS_NOINTEGRITY)
+		return open_dummy_log(sb);
+
+	if (sbi->mntflag & JFS_INLINELOG)
+		return open_inline_log(sb);
+
+	mutex_lock(&jfs_log_mutex);
+	list_for_each_entry(log, &jfs_external_logs, journal_list) {
+		if (log->bdev->bd_dev == sbi->logdev) {
+			if (!uuid_equal(&log->uuid, &sbi->loguuid)) {
+				jfs_warn("wrong uuid on JFS journal");
+				mutex_unlock(&jfs_log_mutex);
+				return -EINVAL;
+			}
+			/*
+			 * add file system to log active file system list
+			 */
+			if ((rc = lmLogFileSystem(log, sbi, 1))) {
+				mutex_unlock(&jfs_log_mutex);
+				return rc;
+			}
+			goto journal_found;
+		}
+	}
+
+	if (!(log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL))) {
+		mutex_unlock(&jfs_log_mutex);
+		return -ENOMEM;
+	}
+	INIT_LIST_HEAD(&log->sb_list);
+	init_waitqueue_head(&log->syncwait);
+
+	/*
+	 *	external log as separate logical volume
+	 *
+	 * file systems to log may have n-to-1 relationship;
+	 */
+
+	bdev = blkdev_get_by_dev(sbi->logdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
+				 log);
+	if (IS_ERR(bdev)) {
+		rc = PTR_ERR(bdev);
+		goto free;
+	}
+
+	log->bdev = bdev;
+	uuid_copy(&log->uuid, &sbi->loguuid);
+
+	/*
+	 * initialize log:
+	 */
+	if ((rc = lmLogInit(log)))
+		goto close;
+
+	list_add(&log->journal_list, &jfs_external_logs);
+
+	/*
+	 * add file system to log active file system list
+	 */
+	if ((rc = lmLogFileSystem(log, sbi, 1)))
+		goto shutdown;
+
+journal_found:
+	LOG_LOCK(log);
+	list_add(&sbi->log_list, &log->sb_list);
+	sbi->log = log;
+	LOG_UNLOCK(log);
+
+	mutex_unlock(&jfs_log_mutex);
+	return 0;
+
+	/*
+	 *	unwind on error
+	 */
+      shutdown:		/* unwind lbmLogInit() */
+	list_del(&log->journal_list);
+	lbmLogShutdown(log);
+
+      close:		/* close external log device */
+	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
+
+      free:		/* free log descriptor */
+	mutex_unlock(&jfs_log_mutex);
+	kfree(log);
+
+	jfs_warn("lmLogOpen: exit(%d)", rc);
+	return rc;
+}
+
+static int open_inline_log(struct super_block *sb)
+{
+	struct jfs_log *log;
+	int rc;
+
+	if (!(log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL)))
+		return -ENOMEM;
+	INIT_LIST_HEAD(&log->sb_list);
+	init_waitqueue_head(&log->syncwait);
+
+	set_bit(log_INLINELOG, &log->flag);
+	log->bdev = sb->s_bdev;
+	log->base = addressPXD(&JFS_SBI(sb)->logpxd);
+	log->size = lengthPXD(&JFS_SBI(sb)->logpxd) >>
+	    (L2LOGPSIZE - sb->s_blocksize_bits);
+	log->l2bsize = sb->s_blocksize_bits;
+	ASSERT(L2LOGPSIZE >= sb->s_blocksize_bits);
+
+	/*
+	 * initialize log.
+	 */
+	if ((rc = lmLogInit(log))) {
+		kfree(log);
+		jfs_warn("lmLogOpen: exit(%d)", rc);
+		return rc;
+	}
+
+	list_add(&JFS_SBI(sb)->log_list, &log->sb_list);
+	JFS_SBI(sb)->log = log;
+
+	return rc;
+}
+
+static int open_dummy_log(struct super_block *sb)
+{
+	int rc;
+
+	mutex_lock(&jfs_log_mutex);
+	if (!dummy_log) {
+		dummy_log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL);
+		if (!dummy_log) {
+			mutex_unlock(&jfs_log_mutex);
+			return -ENOMEM;
+		}
+		INIT_LIST_HEAD(&dummy_log->sb_list);
+		init_waitqueue_head(&dummy_log->syncwait);
+		dummy_log->no_integrity = 1;
+		/* Make up some stuff */
+		dummy_log->base = 0;
+		dummy_log->size = 1024;
+		rc = lmLogInit(dummy_log);
+		if (rc) {
+			kfree(dummy_log);
+			dummy_log = NULL;
+			mutex_unlock(&jfs_log_mutex);
+			return rc;
+		}
+	}
+
+	LOG_LOCK(dummy_log);
+	list_add(&JFS_SBI(sb)->log_list, &dummy_log->sb_list);
+	JFS_SBI(sb)->log = dummy_log;
+	LOG_UNLOCK(dummy_log);
+	mutex_unlock(&jfs_log_mutex);
+
+	return 0;
+}
+
+/*
+ * NAME:	lmLogInit()
+ *
+ * FUNCTION:	log initialization at first log open.
+ *
+ *	logredo() (or logformat()) should have been run previously.
+ *	initialize the log from log superblock.
+ *	set the log state in the superblock to LOGMOUNT and
+ *	write SYNCPT log record.
+ *
+ * PARAMETER:	log	- log structure
+ *
+ * RETURN:	0	- if ok
+ *		-EINVAL	- bad log magic number or superblock dirty
+ *		error returned from logwait()
+ *
+ * serialization: single first open thread
+ */
+int lmLogInit(struct jfs_log * log)
+{
+	int rc = 0;
+	struct lrd lrd;
+	struct logsuper *logsuper;
+	struct lbuf *bpsuper;
+	struct lbuf *bp;
+	struct logpage *lp;
+	int lsn = 0;
+
+	jfs_info("lmLogInit: log:0x%p", log);
+
+	/* initialize the group commit serialization lock */
+	LOGGC_LOCK_INIT(log);
+
+	/* allocate/initialize the log write serialization lock */
+	LOG_LOCK_INIT(log);
+
+	LOGSYNC_LOCK_INIT(log);
+
+	INIT_LIST_HEAD(&log->synclist);
+
+	INIT_LIST_HEAD(&log->cqueue);
+	log->flush_tblk = NULL;
+
+	log->count = 0;
+
+	/*
+	 * initialize log i/o
+	 */
+	if ((rc = lbmLogInit(log)))
+		return rc;
+
+	if (!test_bit(log_INLINELOG, &log->flag))
+		log->l2bsize = L2LOGPSIZE;
+
+	/* check for disabled journaling to disk */
+	if (log->no_integrity) {
+		/*
+		 * Journal pages will still be filled.  When the time comes
+		 * to actually do the I/O, the write is not done, and the
+		 * endio routine is called directly.
+		 */
+		bp = lbmAllocate(log , 0);
+		log->bp = bp;
+		bp->l_pn = bp->l_eor = 0;
+	} else {
+		/*
+		 * validate log superblock
+		 */
+		if ((rc = lbmRead(log, 1, &bpsuper)))
+			goto errout10;
+
+		logsuper = (struct logsuper *) bpsuper->l_ldata;
+
+		if (logsuper->magic != cpu_to_le32(LOGMAGIC)) {
+			jfs_warn("*** Log Format Error ! ***");
+			rc = -EINVAL;
+			goto errout20;
+		}
+
+		/* logredo() should have been run successfully. */
+		if (logsuper->state != cpu_to_le32(LOGREDONE)) {
+			jfs_warn("*** Log Is Dirty ! ***");
+			rc = -EINVAL;
+			goto errout20;
+		}
+
+		/* initialize log from log superblock */
+		if (test_bit(log_INLINELOG,&log->flag)) {
+			if (log->size != le32_to_cpu(logsuper->size)) {
+				rc = -EINVAL;
+				goto errout20;
+			}
+			jfs_info("lmLogInit: inline log:0x%p base:0x%Lx size:0x%x",
+				 log, (unsigned long long)log->base, log->size);
+		} else {
+			if (!uuid_equal(&logsuper->uuid, &log->uuid)) {
+				jfs_warn("wrong uuid on JFS log device");
+				rc = -EINVAL;
+				goto errout20;
+			}
+			log->size = le32_to_cpu(logsuper->size);
+			log->l2bsize = le32_to_cpu(logsuper->l2bsize);
+			jfs_info("lmLogInit: external log:0x%p base:0x%Lx size:0x%x",
+				 log, (unsigned long long)log->base, log->size);
+		}
+
+		log->page = le32_to_cpu(logsuper->end) / LOGPSIZE;
+		log->eor = le32_to_cpu(logsuper->end) - (LOGPSIZE * log->page);
+
+		/*
+		 * initialize for log append write mode
+		 */
+		/* establish current/end-of-log page/buffer */
+		if ((rc = lbmRead(log, log->page, &bp)))
+			goto errout20;
+
+		lp = (struct logpage *) bp->l_ldata;
+
+		jfs_info("lmLogInit: lsn:0x%x page:%d eor:%d:%d",
+			 le32_to_cpu(logsuper->end), log->page, log->eor,
+			 le16_to_cpu(lp->h.eor));
+
+		log->bp = bp;
+		bp->l_pn = log->page;
+		bp->l_eor = log->eor;
+
+		/* if current page is full, move on to next page */
+		if (log->eor >= LOGPSIZE - LOGPTLRSIZE)
+			lmNextPage(log);
+
+		/*
+		 * initialize log syncpoint
+		 */
+		/*
+		 * write the first SYNCPT record with syncpoint = 0
+		 * (i.e., log redo up to HERE !);
+		 * remove current page from lbm write queue at end of pageout
+		 * (to write log superblock update), but do not release to
+		 * freelist;
+		 */
+		lrd.logtid = 0;
+		lrd.backchain = 0;
+		lrd.type = cpu_to_le16(LOG_SYNCPT);
+		lrd.length = 0;
+		lrd.log.syncpt.sync = 0;
+		lsn = lmWriteRecord(log, NULL, &lrd, NULL);
+		bp = log->bp;
+		bp->l_ceor = bp->l_eor;
+		lp = (struct logpage *) bp->l_ldata;
+		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
+		lbmWrite(log, bp, lbmWRITE | lbmSYNC, 0);
+		if ((rc = lbmIOWait(bp, 0)))
+			goto errout30;
+
+		/*
+		 * update/write superblock
+		 */
+		logsuper->state = cpu_to_le32(LOGMOUNT);
+		log->serial = le32_to_cpu(logsuper->serial) + 1;
+		logsuper->serial = cpu_to_le32(log->serial);
+		lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
+		if ((rc = lbmIOWait(bpsuper, lbmFREE)))
+			goto errout30;
+	}
+
+	/* initialize logsync parameters */
+	log->logsize = (log->size - 2) << L2LOGPSIZE;
+	log->lsn = lsn;
+	log->syncpt = lsn;
+	log->sync = log->syncpt;
+	log->nextsync = LOGSYNC_DELTA(log->logsize);
+
+	jfs_info("lmLogInit: lsn:0x%x syncpt:0x%x sync:0x%x",
+		 log->lsn, log->syncpt, log->sync);
+
+	/*
+	 * initialize for lazy/group commit
+	 */
+	log->clsn = lsn;
+
+	return 0;
+
+	/*
+	 *	unwind on error
+	 */
+      errout30:		/* release log page */
+	log->wqueue = NULL;
+	bp->l_wqnext = NULL;
+	lbmFree(bp);
+
+      errout20:		/* release log superblock */
+	lbmFree(bpsuper);
+
+      errout10:		/* unwind lbmLogInit() */
+	lbmLogShutdown(log);
+
+	jfs_warn("lmLogInit: exit(%d)", rc);
+	return rc;
+}
+
+
+/*
+ * NAME:	lmLogClose()
+ *
+ * FUNCTION:	remove file system <ipmnt> from active list of log <iplog>
+ *		and close it on last close.
+ *
+ * PARAMETER:	sb	- superblock
+ *
+ * RETURN:	errors from subroutines
+ *
+ * serialization:
+ */
+int lmLogClose(struct super_block *sb)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct jfs_log *log = sbi->log;
+	struct block_device *bdev;
+	int rc = 0;
+
+	jfs_info("lmLogClose: log:0x%p", log);
+
+	mutex_lock(&jfs_log_mutex);
+	LOG_LOCK(log);
+	list_del(&sbi->log_list);
+	LOG_UNLOCK(log);
+	sbi->log = NULL;
+
+	/*
+	 * We need to make sure all of the "written" metapages
+	 * actually make it to disk
+	 */
+	sync_blockdev(sb->s_bdev);
+
+	if (test_bit(log_INLINELOG, &log->flag)) {
+		/*
+		 *	in-line log in host file system
+		 */
+		rc = lmLogShutdown(log);
+		kfree(log);
+		goto out;
+	}
+
+	if (!log->no_integrity)
+		lmLogFileSystem(log, sbi, 0);
+
+	if (!list_empty(&log->sb_list))
+		goto out;
+
+	/*
+	 * TODO: ensure that the dummy_log is in a state to allow
+	 * lbmLogShutdown to deallocate all the buffers and call
+	 * kfree against dummy_log.  For now, leave dummy_log & its
+	 * buffers in memory, and resuse if another no-integrity mount
+	 * is requested.
+	 */
+	if (log->no_integrity)
+		goto out;
+
+	/*
+	 *	external log as separate logical volume
+	 */
+	list_del(&log->journal_list);
+	bdev = log->bdev;
+	rc = lmLogShutdown(log);
+
+	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
+
+	kfree(log);
+
+      out:
+	mutex_unlock(&jfs_log_mutex);
+	jfs_info("lmLogClose: exit(%d)", rc);
+	return rc;
+}
+
+
+/*
+ * NAME:	jfs_flush_journal()
+ *
+ * FUNCTION:	initiate write of any outstanding transactions to the journal
+ *		and optionally wait until they are all written to disk
+ *
+ *		wait == 0  flush until latest txn is committed, don't wait
+ *		wait == 1  flush until latest txn is committed, wait
+ *		wait > 1   flush until all txn's are complete, wait
+ */
+void jfs_flush_journal(struct jfs_log *log, int wait)
+{
+	int i;
+	struct tblock *target = NULL;
+
+	/* jfs_write_inode may call us during read-only mount */
+	if (!log)
+		return;
+
+	jfs_info("jfs_flush_journal: log:0x%p wait=%d", log, wait);
+
+	LOGGC_LOCK(log);
+
+	if (!list_empty(&log->cqueue)) {
+		/*
+		 * This ensures that we will keep writing to the journal as long
+		 * as there are unwritten commit records
+		 */
+		target = list_entry(log->cqueue.prev, struct tblock, cqueue);
+
+		if (test_bit(log_FLUSH, &log->flag)) {
+			/*
+			 * We're already flushing.
+			 * if flush_tblk is NULL, we are flushing everything,
+			 * so leave it that way.  Otherwise, update it to the
+			 * latest transaction
+			 */
+			if (log->flush_tblk)
+				log->flush_tblk = target;
+		} else {
+			/* Only flush until latest transaction is committed */
+			log->flush_tblk = target;
+			set_bit(log_FLUSH, &log->flag);
+
+			/*
+			 * Initiate I/O on outstanding transactions
+			 */
+			if (!(log->cflag & logGC_PAGEOUT)) {
+				log->cflag |= logGC_PAGEOUT;
+				lmGCwrite(log, 0);
+			}
+		}
+	}
+	if ((wait > 1) || test_bit(log_SYNCBARRIER, &log->flag)) {
+		/* Flush until all activity complete */
+		set_bit(log_FLUSH, &log->flag);
+		log->flush_tblk = NULL;
+	}
+
+	if (wait && target && !(target->flag & tblkGC_COMMITTED)) {
+		DECLARE_WAITQUEUE(__wait, current);
+
+		add_wait_queue(&target->gcwait, &__wait);
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		LOGGC_UNLOCK(log);
+		schedule();
+		LOGGC_LOCK(log);
+		remove_wait_queue(&target->gcwait, &__wait);
+	}
+	LOGGC_UNLOCK(log);
+
+	if (wait < 2)
+		return;
+
+	write_special_inodes(log, filemap_fdatawrite);
+
+	/*
+	 * If there was recent activity, we may need to wait
+	 * for the lazycommit thread to catch up
+	 */
+	if ((!list_empty(&log->cqueue)) || !list_empty(&log->synclist)) {
+		for (i = 0; i < 200; i++) {	/* Too much? */
+			msleep(250);
+			write_special_inodes(log, filemap_fdatawrite);
+			if (list_empty(&log->cqueue) &&
+			    list_empty(&log->synclist))
+				break;
+		}
+	}
+	assert(list_empty(&log->cqueue));
+
+#ifdef CONFIG_JFS_DEBUG
+	if (!list_empty(&log->synclist)) {
+		struct logsyncblk *lp;
+
+		printk(KERN_ERR "jfs_flush_journal: synclist not empty\n");
+		list_for_each_entry(lp, &log->synclist, synclist) {
+			if (lp->xflag & COMMIT_PAGE) {
+				struct metapage *mp = (struct metapage *)lp;
+				print_hex_dump(KERN_ERR, "metapage: ",
+					       DUMP_PREFIX_ADDRESS, 16, 4,
+					       mp, sizeof(struct metapage), 0);
+				print_hex_dump(KERN_ERR, "page: ",
+					       DUMP_PREFIX_ADDRESS, 16,
+					       sizeof(long), mp->page,
+					       sizeof(struct page), 0);
+			} else
+				print_hex_dump(KERN_ERR, "tblock:",
+					       DUMP_PREFIX_ADDRESS, 16, 4,
+					       lp, sizeof(struct tblock), 0);
+		}
+	}
+#else
+	WARN_ON(!list_empty(&log->synclist));
+#endif
+	clear_bit(log_FLUSH, &log->flag);
+}
+
+/*
+ * NAME:	lmLogShutdown()
+ *
+ * FUNCTION:	log shutdown at last LogClose().
+ *
+ *		write log syncpt record.
+ *		update super block to set redone flag to 0.
+ *
+ * PARAMETER:	log	- log inode
+ *
+ * RETURN:	0	- success
+ *
+ * serialization: single last close thread
+ */
+int lmLogShutdown(struct jfs_log * log)
+{
+	int rc;
+	struct lrd lrd;
+	int lsn;
+	struct logsuper *logsuper;
+	struct lbuf *bpsuper;
+	struct lbuf *bp;
+	struct logpage *lp;
+
+	jfs_info("lmLogShutdown: log:0x%p", log);
+
+	jfs_flush_journal(log, 2);
+
+	/*
+	 * write the last SYNCPT record with syncpoint = 0
+	 * (i.e., log redo up to HERE !)
+	 */
+	lrd.logtid = 0;
+	lrd.backchain = 0;
+	lrd.type = cpu_to_le16(LOG_SYNCPT);
+	lrd.length = 0;
+	lrd.log.syncpt.sync = 0;
+
+	lsn = lmWriteRecord(log, NULL, &lrd, NULL);
+	bp = log->bp;
+	lp = (struct logpage *) bp->l_ldata;
+	lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
+	lbmWrite(log, log->bp, lbmWRITE | lbmRELEASE | lbmSYNC, 0);
+	lbmIOWait(log->bp, lbmFREE);
+	log->bp = NULL;
+
+	/*
+	 * synchronous update log superblock
+	 * mark log state as shutdown cleanly
+	 * (i.e., Log does not need to be replayed).
+	 */
+	if ((rc = lbmRead(log, 1, &bpsuper)))
+		goto out;
+
+	logsuper = (struct logsuper *) bpsuper->l_ldata;
+	logsuper->state = cpu_to_le32(LOGREDONE);
+	logsuper->end = cpu_to_le32(lsn);
+	lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
+	rc = lbmIOWait(bpsuper, lbmFREE);
+
+	jfs_info("lmLogShutdown: lsn:0x%x page:%d eor:%d",
+		 lsn, log->page, log->eor);
+
+      out:
+	/*
+	 * shutdown per log i/o
+	 */
+	lbmLogShutdown(log);
+
+	if (rc) {
+		jfs_warn("lmLogShutdown: exit(%d)", rc);
+	}
+	return rc;
+}
+
+
+/*
+ * NAME:	lmLogFileSystem()
+ *
+ * FUNCTION:	insert (<activate> = true)/remove (<activate> = false)
+ *	file system into/from log active file system list.
+ *
+ * PARAMETE:	log	- pointer to logs inode.
+ *		fsdev	- kdev_t of filesystem.
+ *		serial	- pointer to returned log serial number
+ *		activate - insert/remove device from active list.
+ *
+ * RETURN:	0	- success
+ *		errors returned by vms_iowait().
+ */
+static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
+			   int activate)
+{
+	int rc = 0;
+	int i;
+	struct logsuper *logsuper;
+	struct lbuf *bpsuper;
+	uuid_t *uuid = &sbi->uuid;
+
+	/*
+	 * insert/remove file system device to log active file system list.
+	 */
+	if ((rc = lbmRead(log, 1, &bpsuper)))
+		return rc;
+
+	logsuper = (struct logsuper *) bpsuper->l_ldata;
+	if (activate) {
+		for (i = 0; i < MAX_ACTIVE; i++)
+			if (uuid_is_null(&logsuper->active[i].uuid)) {
+				uuid_copy(&logsuper->active[i].uuid, uuid);
+				sbi->aggregate = i;
+				break;
+			}
+		if (i == MAX_ACTIVE) {
+			jfs_warn("Too many file systems sharing journal!");
+			lbmFree(bpsuper);
+			return -EMFILE;	/* Is there a better rc? */
+		}
+	} else {
+		for (i = 0; i < MAX_ACTIVE; i++)
+			if (uuid_equal(&logsuper->active[i].uuid, uuid)) {
+				uuid_copy(&logsuper->active[i].uuid,
+					  &uuid_null);
+				break;
+			}
+		if (i == MAX_ACTIVE) {
+			jfs_warn("Somebody stomped on the journal!");
+			lbmFree(bpsuper);
+			return -EIO;
+		}
+
+	}
+
+	/*
+	 * synchronous write log superblock:
+	 *
+	 * write sidestream bypassing write queue:
+	 * at file system mount, log super block is updated for
+	 * activation of the file system before any log record
+	 * (MOUNT record) of the file system, and at file system
+	 * unmount, all meta data for the file system has been
+	 * flushed before log super block is updated for deactivation
+	 * of the file system.
+	 */
+	lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
+	rc = lbmIOWait(bpsuper, lbmFREE);
+
+	return rc;
+}
+
+/*
+ *		log buffer manager (lbm)
+ *		------------------------
+ *
+ * special purpose buffer manager supporting log i/o requirements.
+ *
+ * per log write queue:
+ * log pageout occurs in serial order by fifo write queue and
+ * restricting to a single i/o in pregress at any one time.
+ * a circular singly-linked list
+ * (log->wrqueue points to the tail, and buffers are linked via
+ * bp->wrqueue field), and
+ * maintains log page in pageout ot waiting for pageout in serial pageout.
+ */
+
+/*
+ *	lbmLogInit()
+ *
+ * initialize per log I/O setup at lmLogInit()
+ */
+static int lbmLogInit(struct jfs_log * log)
+{				/* log inode */
+	int i;
+	struct lbuf *lbuf;
+
+	jfs_info("lbmLogInit: log:0x%p", log);
+
+	/* initialize current buffer cursor */
+	log->bp = NULL;
+
+	/* initialize log device write queue */
+	log->wqueue = NULL;
+
+	/*
+	 * Each log has its own buffer pages allocated to it.  These are
+	 * not managed by the page cache.  This ensures that a transaction
+	 * writing to the log does not block trying to allocate a page from
+	 * the page cache (for the log).  This would be bad, since page
+	 * allocation waits on the kswapd thread that may be committing inodes
+	 * which would cause log activity.  Was that clear?  I'm trying to
+	 * avoid deadlock here.
+	 */
+	init_waitqueue_head(&log->free_wait);
+
+	log->lbuf_free = NULL;
+
+	for (i = 0; i < LOGPAGES;) {
+		char *buffer;
+		uint offset;
+		struct page *page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+
+		if (!page)
+			goto error;
+		buffer = page_address(page);
+		for (offset = 0; offset < PAGE_SIZE; offset += LOGPSIZE) {
+			lbuf = kmalloc(sizeof(struct lbuf), GFP_KERNEL);
+			if (lbuf == NULL) {
+				if (offset == 0)
+					__free_page(page);
+				goto error;
+			}
+			if (offset) /* we already have one reference */
+				get_page(page);
+			lbuf->l_offset = offset;
+			lbuf->l_ldata = buffer + offset;
+			lbuf->l_page = page;
+			lbuf->l_log = log;
+			init_waitqueue_head(&lbuf->l_ioevent);
+
+			lbuf->l_freelist = log->lbuf_free;
+			log->lbuf_free = lbuf;
+			i++;
+		}
+	}
+
+	return (0);
+
+      error:
+	lbmLogShutdown(log);
+	return -ENOMEM;
+}
+
+
+/*
+ *	lbmLogShutdown()
+ *
+ * finalize per log I/O setup at lmLogShutdown()
+ */
+static void lbmLogShutdown(struct jfs_log * log)
+{
+	struct lbuf *lbuf;
+
+	jfs_info("lbmLogShutdown: log:0x%p", log);
+
+	lbuf = log->lbuf_free;
+	while (lbuf) {
+		struct lbuf *next = lbuf->l_freelist;
+		__free_page(lbuf->l_page);
+		kfree(lbuf);
+		lbuf = next;
+	}
+}
+
+
+/*
+ *	lbmAllocate()
+ *
+ * allocate an empty log buffer
+ */
+static struct lbuf *lbmAllocate(struct jfs_log * log, int pn)
+{
+	struct lbuf *bp;
+	unsigned long flags;
+
+	/*
+	 * recycle from log buffer freelist if any
+	 */
+	LCACHE_LOCK(flags);
+	LCACHE_SLEEP_COND(log->free_wait, (bp = log->lbuf_free), flags);
+	log->lbuf_free = bp->l_freelist;
+	LCACHE_UNLOCK(flags);
+
+	bp->l_flag = 0;
+
+	bp->l_wqnext = NULL;
+	bp->l_freelist = NULL;
+
+	bp->l_pn = pn;
+	bp->l_blkno = log->base + (pn << (L2LOGPSIZE - log->l2bsize));
+	bp->l_ceor = 0;
+
+	return bp;
+}
+
+
+/*
+ *	lbmFree()
+ *
+ * release a log buffer to freelist
+ */
+static void lbmFree(struct lbuf * bp)
+{
+	unsigned long flags;
+
+	LCACHE_LOCK(flags);
+
+	lbmfree(bp);
+
+	LCACHE_UNLOCK(flags);
+}
+
+static void lbmfree(struct lbuf * bp)
+{
+	struct jfs_log *log = bp->l_log;
+
+	assert(bp->l_wqnext == NULL);
+
+	/*
+	 * return the buffer to head of freelist
+	 */
+	bp->l_freelist = log->lbuf_free;
+	log->lbuf_free = bp;
+
+	wake_up(&log->free_wait);
+	return;
+}
+
+
+/*
+ * NAME:	lbmRedrive
+ *
+ * FUNCTION:	add a log buffer to the log redrive list
+ *
+ * PARAMETER:
+ *	bp	- log buffer
+ *
+ * NOTES:
+ *	Takes log_redrive_lock.
+ */
+static inline void lbmRedrive(struct lbuf *bp)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&log_redrive_lock, flags);
+	bp->l_redrive_next = log_redrive_list;
+	log_redrive_list = bp;
+	spin_unlock_irqrestore(&log_redrive_lock, flags);
+
+	wake_up_process(jfsIOthread);
+}
+
+
+/*
+ *	lbmRead()
+ */
+static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp)
+{
+	struct bio *bio;
+	struct lbuf *bp;
+
+	/*
+	 * allocate a log buffer
+	 */
+	*bpp = bp = lbmAllocate(log, pn);
+	jfs_info("lbmRead: bp:0x%p pn:0x%x", bp, pn);
+
+	bp->l_flag |= lbmREAD;
+
+	bio = bio_alloc(log->bdev, 1, REQ_OP_READ, GFP_NOFS);
+	bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
+	bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
+	BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
+
+	bio->bi_end_io = lbmIODone;
+	bio->bi_private = bp;
+	/*check if journaling to disk has been disabled*/
+	if (log->no_integrity) {
+		bio->bi_iter.bi_size = 0;
+		lbmIODone(bio);
+	} else {
+		submit_bio(bio);
+	}
+
+	wait_event(bp->l_ioevent, (bp->l_flag != lbmREAD));
+
+	return 0;
+}
+
+
+/*
+ *	lbmWrite()
+ *
+ * buffer at head of pageout queue stays after completion of
+ * partial-page pageout and redriven by explicit initiation of
+ * pageout by caller until full-page pageout is completed and
+ * released.
+ *
+ * device driver i/o done redrives pageout of new buffer at
+ * head of pageout queue when current buffer at head of pageout
+ * queue is released at the completion of its full-page pageout.
+ *
+ * LOGGC_LOCK() serializes lbmWrite() by lmNextPage() and lmGroupCommit().
+ * LCACHE_LOCK() serializes xflag between lbmWrite() and lbmIODone()
+ */
+static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag,
+		     int cant_block)
+{
+	struct lbuf *tail;
+	unsigned long flags;
+
+	jfs_info("lbmWrite: bp:0x%p flag:0x%x pn:0x%x", bp, flag, bp->l_pn);
+
+	/* map the logical block address to physical block address */
+	bp->l_blkno =
+	    log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
+
+	LCACHE_LOCK(flags);		/* disable+lock */
+
+	/*
+	 * initialize buffer for device driver
+	 */
+	bp->l_flag = flag;
+
+	/*
+	 *	insert bp at tail of write queue associated with log
+	 *
+	 * (request is either for bp already/currently at head of queue
+	 * or new bp to be inserted at tail)
+	 */
+	tail = log->wqueue;
+
+	/* is buffer not already on write queue ? */
+	if (bp->l_wqnext == NULL) {
+		/* insert at tail of wqueue */
+		if (tail == NULL) {
+			log->wqueue = bp;
+			bp->l_wqnext = bp;
+		} else {
+			log->wqueue = bp;
+			bp->l_wqnext = tail->l_wqnext;
+			tail->l_wqnext = bp;
+		}
+
+		tail = bp;
+	}
+
+	/* is buffer at head of wqueue and for write ? */
+	if ((bp != tail->l_wqnext) || !(flag & lbmWRITE)) {
+		LCACHE_UNLOCK(flags);	/* unlock+enable */
+		return;
+	}
+
+	LCACHE_UNLOCK(flags);	/* unlock+enable */
+
+	if (cant_block)
+		lbmRedrive(bp);
+	else if (flag & lbmSYNC)
+		lbmStartIO(bp);
+	else {
+		LOGGC_UNLOCK(log);
+		lbmStartIO(bp);
+		LOGGC_LOCK(log);
+	}
+}
+
+
+/*
+ *	lbmDirectWrite()
+ *
+ * initiate pageout bypassing write queue for sidestream
+ * (e.g., log superblock) write;
+ */
+static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag)
+{
+	jfs_info("lbmDirectWrite: bp:0x%p flag:0x%x pn:0x%x",
+		 bp, flag, bp->l_pn);
+
+	/*
+	 * initialize buffer for device driver
+	 */
+	bp->l_flag = flag | lbmDIRECT;
+
+	/* map the logical block address to physical block address */
+	bp->l_blkno =
+	    log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
+
+	/*
+	 *	initiate pageout of the page
+	 */
+	lbmStartIO(bp);
+}
+
+
+/*
+ * NAME:	lbmStartIO()
+ *
+ * FUNCTION:	Interface to DD strategy routine
+ *
+ * RETURN:	none
+ *
+ * serialization: LCACHE_LOCK() is NOT held during log i/o;
+ */
+static void lbmStartIO(struct lbuf * bp)
+{
+	struct bio *bio;
+	struct jfs_log *log = bp->l_log;
+
+	jfs_info("lbmStartIO");
+
+	bio = bio_alloc(log->bdev, 1, REQ_OP_WRITE | REQ_SYNC, GFP_NOFS);
+	bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
+	bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
+	BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
+
+	bio->bi_end_io = lbmIODone;
+	bio->bi_private = bp;
+
+	/* check if journaling to disk has been disabled */
+	if (log->no_integrity) {
+		bio->bi_iter.bi_size = 0;
+		lbmIODone(bio);
+	} else {
+		submit_bio(bio);
+		INCREMENT(lmStat.submitted);
+	}
+}
+
+
+/*
+ *	lbmIOWait()
+ */
+static int lbmIOWait(struct lbuf * bp, int flag)
+{
+	unsigned long flags;
+	int rc = 0;
+
+	jfs_info("lbmIOWait1: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
+
+	LCACHE_LOCK(flags);		/* disable+lock */
+
+	LCACHE_SLEEP_COND(bp->l_ioevent, (bp->l_flag & lbmDONE), flags);
+
+	rc = (bp->l_flag & lbmERROR) ? -EIO : 0;
+
+	if (flag & lbmFREE)
+		lbmfree(bp);
+
+	LCACHE_UNLOCK(flags);	/* unlock+enable */
+
+	jfs_info("lbmIOWait2: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
+	return rc;
+}
+
+/*
+ *	lbmIODone()
+ *
+ * executed at INTIODONE level
+ */
+static void lbmIODone(struct bio *bio)
+{
+	struct lbuf *bp = bio->bi_private;
+	struct lbuf *nextbp, *tail;
+	struct jfs_log *log;
+	unsigned long flags;
+
+	/*
+	 * get back jfs buffer bound to the i/o buffer
+	 */
+	jfs_info("lbmIODone: bp:0x%p flag:0x%x", bp, bp->l_flag);
+
+	LCACHE_LOCK(flags);		/* disable+lock */
+
+	bp->l_flag |= lbmDONE;
+
+	if (bio->bi_status) {
+		bp->l_flag |= lbmERROR;
+
+		jfs_err("lbmIODone: I/O error in JFS log");
+	}
+
+	bio_put(bio);
+
+	/*
+	 *	pagein completion
+	 */
+	if (bp->l_flag & lbmREAD) {
+		bp->l_flag &= ~lbmREAD;
+
+		LCACHE_UNLOCK(flags);	/* unlock+enable */
+
+		/* wakeup I/O initiator */
+		LCACHE_WAKEUP(&bp->l_ioevent);
+
+		return;
+	}
+
+	/*
+	 *	pageout completion
+	 *
+	 * the bp at the head of write queue has completed pageout.
+	 *
+	 * if single-commit/full-page pageout, remove the current buffer
+	 * from head of pageout queue, and redrive pageout with
+	 * the new buffer at head of pageout queue;
+	 * otherwise, the partial-page pageout buffer stays at
+	 * the head of pageout queue to be redriven for pageout
+	 * by lmGroupCommit() until full-page pageout is completed.
+	 */
+	bp->l_flag &= ~lbmWRITE;
+	INCREMENT(lmStat.pagedone);
+
+	/* update committed lsn */
+	log = bp->l_log;
+	log->clsn = (bp->l_pn << L2LOGPSIZE) + bp->l_ceor;
+
+	if (bp->l_flag & lbmDIRECT) {
+		LCACHE_WAKEUP(&bp->l_ioevent);
+		LCACHE_UNLOCK(flags);
+		return;
+	}
+
+	tail = log->wqueue;
+
+	/* single element queue */
+	if (bp == tail) {
+		/* remove head buffer of full-page pageout
+		 * from log device write queue
+		 */
+		if (bp->l_flag & lbmRELEASE) {
+			log->wqueue = NULL;
+			bp->l_wqnext = NULL;
+		}
+	}
+	/* multi element queue */
+	else {
+		/* remove head buffer of full-page pageout
+		 * from log device write queue
+		 */
+		if (bp->l_flag & lbmRELEASE) {
+			nextbp = tail->l_wqnext = bp->l_wqnext;
+			bp->l_wqnext = NULL;
+
+			/*
+			 * redrive pageout of next page at head of write queue:
+			 * redrive next page without any bound tblk
+			 * (i.e., page w/o any COMMIT records), or
+			 * first page of new group commit which has been
+			 * queued after current page (subsequent pageout
+			 * is performed synchronously, except page without
+			 * any COMMITs) by lmGroupCommit() as indicated
+			 * by lbmWRITE flag;
+			 */
+			if (nextbp->l_flag & lbmWRITE) {
+				/*
+				 * We can't do the I/O at interrupt time.
+				 * The jfsIO thread can do it
+				 */
+				lbmRedrive(nextbp);
+			}
+		}
+	}
+
+	/*
+	 *	synchronous pageout:
+	 *
+	 * buffer has not necessarily been removed from write queue
+	 * (e.g., synchronous write of partial-page with COMMIT):
+	 * leave buffer for i/o initiator to dispose
+	 */
+	if (bp->l_flag & lbmSYNC) {
+		LCACHE_UNLOCK(flags);	/* unlock+enable */
+
+		/* wakeup I/O initiator */
+		LCACHE_WAKEUP(&bp->l_ioevent);
+	}
+
+	/*
+	 *	Group Commit pageout:
+	 */
+	else if (bp->l_flag & lbmGC) {
+		LCACHE_UNLOCK(flags);
+		lmPostGC(bp);
+	}
+
+	/*
+	 *	asynchronous pageout:
+	 *
+	 * buffer must have been removed from write queue:
+	 * insert buffer at head of freelist where it can be recycled
+	 */
+	else {
+		assert(bp->l_flag & lbmRELEASE);
+		assert(bp->l_flag & lbmFREE);
+		lbmfree(bp);
+
+		LCACHE_UNLOCK(flags);	/* unlock+enable */
+	}
+}
+
+int jfsIOWait(void *arg)
+{
+	struct lbuf *bp;
+
+	do {
+		spin_lock_irq(&log_redrive_lock);
+		while ((bp = log_redrive_list)) {
+			log_redrive_list = bp->l_redrive_next;
+			bp->l_redrive_next = NULL;
+			spin_unlock_irq(&log_redrive_lock);
+			lbmStartIO(bp);
+			spin_lock_irq(&log_redrive_lock);
+		}
+
+		if (freezing(current)) {
+			spin_unlock_irq(&log_redrive_lock);
+			try_to_freeze();
+		} else {
+			set_current_state(TASK_INTERRUPTIBLE);
+			spin_unlock_irq(&log_redrive_lock);
+			schedule();
+		}
+	} while (!kthread_should_stop());
+
+	jfs_info("jfsIOWait being killed!");
+	return 0;
+}
+
+/*
+ * NAME:	lmLogFormat()/jfs_logform()
+ *
+ * FUNCTION:	format file system log
+ *
+ * PARAMETERS:
+ *	log	- volume log
+ *	logAddress - start address of log space in FS block
+ *	logSize	- length of log space in FS block;
+ *
+ * RETURN:	0	- success
+ *		-EIO	- i/o error
+ *
+ * XXX: We're synchronously writing one page at a time.  This needs to
+ *	be improved by writing multiple pages at once.
+ */
+int lmLogFormat(struct jfs_log *log, s64 logAddress, int logSize)
+{
+	int rc = -EIO;
+	struct jfs_sb_info *sbi;
+	struct logsuper *logsuper;
+	struct logpage *lp;
+	int lspn;		/* log sequence page number */
+	struct lrd *lrd_ptr;
+	int npages = 0;
+	struct lbuf *bp;
+
+	jfs_info("lmLogFormat: logAddress:%Ld logSize:%d",
+		 (long long)logAddress, logSize);
+
+	sbi = list_entry(log->sb_list.next, struct jfs_sb_info, log_list);
+
+	/* allocate a log buffer */
+	bp = lbmAllocate(log, 1);
+
+	npages = logSize >> sbi->l2nbperpage;
+
+	/*
+	 *	log space:
+	 *
+	 * page 0 - reserved;
+	 * page 1 - log superblock;
+	 * page 2 - log data page: A SYNC log record is written
+	 *	    into this page at logform time;
+	 * pages 3-N - log data page: set to empty log data pages;
+	 */
+	/*
+	 *	init log superblock: log page 1
+	 */
+	logsuper = (struct logsuper *) bp->l_ldata;
+
+	logsuper->magic = cpu_to_le32(LOGMAGIC);
+	logsuper->version = cpu_to_le32(LOGVERSION);
+	logsuper->state = cpu_to_le32(LOGREDONE);
+	logsuper->flag = cpu_to_le32(sbi->mntflag);	/* ? */
+	logsuper->size = cpu_to_le32(npages);
+	logsuper->bsize = cpu_to_le32(sbi->bsize);
+	logsuper->l2bsize = cpu_to_le32(sbi->l2bsize);
+	logsuper->end = cpu_to_le32(2 * LOGPSIZE + LOGPHDRSIZE + LOGRDSIZE);
+
+	bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
+	bp->l_blkno = logAddress + sbi->nbperpage;
+	lbmStartIO(bp);
+	if ((rc = lbmIOWait(bp, 0)))
+		goto exit;
+
+	/*
+	 *	init pages 2 to npages-1 as log data pages:
+	 *
+	 * log page sequence number (lpsn) initialization:
+	 *
+	 * pn:   0     1     2     3                 n-1
+	 *       +-----+-----+=====+=====+===.....===+=====+
+	 * lspn:             N-1   0     1           N-2
+	 *                   <--- N page circular file ---->
+	 *
+	 * the N (= npages-2) data pages of the log is maintained as
+	 * a circular file for the log records;
+	 * lpsn grows by 1 monotonically as each log page is written
+	 * to the circular file of the log;
+	 * and setLogpage() will not reset the page number even if
+	 * the eor is equal to LOGPHDRSIZE. In order for binary search
+	 * still work in find log end process, we have to simulate the
+	 * log wrap situation at the log format time.
+	 * The 1st log page written will have the highest lpsn. Then
+	 * the succeeding log pages will have ascending order of
+	 * the lspn starting from 0, ... (N-2)
+	 */
+	lp = (struct logpage *) bp->l_ldata;
+	/*
+	 * initialize 1st log page to be written: lpsn = N - 1,
+	 * write a SYNCPT log record is written to this page
+	 */
+	lp->h.page = lp->t.page = cpu_to_le32(npages - 3);
+	lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE + LOGRDSIZE);
+
+	lrd_ptr = (struct lrd *) &lp->data;
+	lrd_ptr->logtid = 0;
+	lrd_ptr->backchain = 0;
+	lrd_ptr->type = cpu_to_le16(LOG_SYNCPT);
+	lrd_ptr->length = 0;
+	lrd_ptr->log.syncpt.sync = 0;
+
+	bp->l_blkno += sbi->nbperpage;
+	bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
+	lbmStartIO(bp);
+	if ((rc = lbmIOWait(bp, 0)))
+		goto exit;
+
+	/*
+	 *	initialize succeeding log pages: lpsn = 0, 1, ..., (N-2)
+	 */
+	for (lspn = 0; lspn < npages - 3; lspn++) {
+		lp->h.page = lp->t.page = cpu_to_le32(lspn);
+		lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
+
+		bp->l_blkno += sbi->nbperpage;
+		bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
+		lbmStartIO(bp);
+		if ((rc = lbmIOWait(bp, 0)))
+			goto exit;
+	}
+
+	rc = 0;
+exit:
+	/*
+	 *	finalize log
+	 */
+	/* release the buffer */
+	lbmFree(bp);
+
+	return rc;
+}
+
+#ifdef CONFIG_JFS_STATISTICS
+int jfs_lmstats_proc_show(struct seq_file *m, void *v)
+{
+	seq_printf(m,
+		       "JFS Logmgr stats\n"
+		       "================\n"
+		       "commits = %d\n"
+		       "writes submitted = %d\n"
+		       "writes completed = %d\n"
+		       "full pages submitted = %d\n"
+		       "partial pages submitted = %d\n",
+		       lmStat.commit,
+		       lmStat.submitted,
+		       lmStat.pagedone,
+		       lmStat.full_page,
+		       lmStat.partial_page);
+	return 0;
+}
+#endif /* CONFIG_JFS_STATISTICS */
diff --git a/fs/jfs/jfs_logmgr.h b/fs/jfs/jfs_logmgr.h
new file mode 100644
index 000000000..805877ce5
--- /dev/null
+++ b/fs/jfs/jfs_logmgr.h
@@ -0,0 +1,500 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+#ifndef	_H_JFS_LOGMGR
+#define _H_JFS_LOGMGR
+
+#include <linux/uuid.h>
+
+#include "jfs_filsys.h"
+#include "jfs_lock.h"
+
+/*
+ *	log manager configuration parameters
+ */
+
+/* log page size */
+#define	LOGPSIZE	4096
+#define	L2LOGPSIZE	12
+
+#define LOGPAGES	16	/* Log pages per mounted file system */
+
+/*
+ *	log logical volume
+ *
+ * a log is used to make the commit operation on journalled
+ * files within the same logical volume group atomic.
+ * a log is implemented with a logical volume.
+ * there is one log per logical volume group.
+ *
+ * block 0 of the log logical volume is not used (ipl etc).
+ * block 1 contains a log "superblock" and is used by logFormat(),
+ * lmLogInit(), lmLogShutdown(), and logRedo() to record status
+ * of the log but is not otherwise used during normal processing.
+ * blocks 2 - (N-1) are used to contain log records.
+ *
+ * when a volume group is varied-on-line, logRedo() must have
+ * been executed before the file systems (logical volumes) in
+ * the volume group can be mounted.
+ */
+/*
+ *	log superblock (block 1 of logical volume)
+ */
+#define	LOGSUPER_B	1
+#define	LOGSTART_B	2
+
+#define	LOGMAGIC	0x87654321
+#define	LOGVERSION	1
+
+#define MAX_ACTIVE	128	/* Max active file systems sharing log */
+
+struct logsuper {
+	__le32 magic;		/* 4: log lv identifier */
+	__le32 version;		/* 4: version number */
+	__le32 serial;		/* 4: log open/mount counter */
+	__le32 size;		/* 4: size in number of LOGPSIZE blocks */
+	__le32 bsize;		/* 4: logical block size in byte */
+	__le32 l2bsize;		/* 4: log2 of bsize */
+
+	__le32 flag;		/* 4: option */
+	__le32 state;		/* 4: state - see below */
+
+	__le32 end;		/* 4: addr of last log record set by logredo */
+	uuid_t uuid;		/* 16: 128-bit journal uuid */
+	char label[16];		/* 16: journal label */
+	struct {
+		uuid_t uuid;
+	} active[MAX_ACTIVE];	/* 2048: active file systems list */
+};
+
+/* log flag: commit option (see jfs_filsys.h) */
+
+/* log state */
+#define	LOGMOUNT	0	/* log mounted by lmLogInit() */
+#define LOGREDONE	1	/* log shutdown by lmLogShutdown().
+				 * log redo completed by logredo().
+				 */
+#define LOGWRAP		2	/* log wrapped */
+#define LOGREADERR	3	/* log read error detected in logredo() */
+
+
+/*
+ *	log logical page
+ *
+ * (this comment should be rewritten !)
+ * the header and trailer structures (h,t) will normally have
+ * the same page and eor value.
+ * An exception to this occurs when a complete page write is not
+ * accomplished on a power failure. Since the hardware may "split write"
+ * sectors in the page, any out of order sequence may occur during powerfail
+ * and needs to be recognized during log replay.  The xor value is
+ * an "exclusive or" of all log words in the page up to eor.  This
+ * 32 bit eor is stored with the top 16 bits in the header and the
+ * bottom 16 bits in the trailer.  logredo can easily recognize pages
+ * that were not completed by reconstructing this eor and checking
+ * the log page.
+ *
+ * Previous versions of the operating system did not allow split
+ * writes and detected partially written records in logredo by
+ * ordering the updates to the header, trailer, and the move of data
+ * into the logdata area.  The order: (1) data is moved (2) header
+ * is updated (3) trailer is updated.  In logredo, when the header
+ * differed from the trailer, the header and trailer were reconciled
+ * as follows: if h.page != t.page they were set to the smaller of
+ * the two and h.eor and t.eor set to 8 (i.e. empty page). if (only)
+ * h.eor != t.eor they were set to the smaller of their two values.
+ */
+struct logpage {
+	struct {		/* header */
+		__le32 page;	/* 4: log sequence page number */
+		__le16 rsrvd;	/* 2: */
+		__le16 eor;	/* 2: end-of-log offset of lasrt record write */
+	} h;
+
+	__le32 data[LOGPSIZE / 4 - 4];	/* log record area */
+
+	struct {		/* trailer */
+		__le32 page;	/* 4: normally the same as h.page */
+		__le16 rsrvd;	/* 2: */
+		__le16 eor;	/* 2: normally the same as h.eor */
+	} t;
+};
+
+#define LOGPHDRSIZE	8	/* log page header size */
+#define LOGPTLRSIZE	8	/* log page trailer size */
+
+
+/*
+ *	log record
+ *
+ * (this comment should be rewritten !)
+ * jfs uses only "after" log records (only a single writer is allowed
+ * in a page, pages are written to temporary paging space if
+ * they must be written to disk before commit, and i/o is
+ * scheduled for modified pages to their home location after
+ * the log records containing the after values and the commit
+ * record is written to the log on disk, undo discards the copy
+ * in main-memory.)
+ *
+ * a log record consists of a data area of variable length followed by
+ * a descriptor of fixed size LOGRDSIZE bytes.
+ * the data area is rounded up to an integral number of 4-bytes and
+ * must be no longer than LOGPSIZE.
+ * the descriptor is of size of multiple of 4-bytes and aligned on a
+ * 4-byte boundary.
+ * records are packed one after the other in the data area of log pages.
+ * (sometimes a DUMMY record is inserted so that at least one record ends
+ * on every page or the longest record is placed on at most two pages).
+ * the field eor in page header/trailer points to the byte following
+ * the last record on a page.
+ */
+
+/* log record types */
+#define LOG_COMMIT		0x8000
+#define LOG_SYNCPT		0x4000
+#define LOG_MOUNT		0x2000
+#define LOG_REDOPAGE		0x0800
+#define LOG_NOREDOPAGE		0x0080
+#define LOG_NOREDOINOEXT	0x0040
+#define LOG_UPDATEMAP		0x0008
+#define LOG_NOREDOFILE		0x0001
+
+/* REDOPAGE/NOREDOPAGE log record data type */
+#define	LOG_INODE		0x0001
+#define	LOG_XTREE		0x0002
+#define	LOG_DTREE		0x0004
+#define	LOG_BTROOT		0x0010
+#define	LOG_EA			0x0020
+#define	LOG_ACL			0x0040
+#define	LOG_DATA		0x0080
+#define	LOG_NEW			0x0100
+#define	LOG_EXTEND		0x0200
+#define LOG_RELOCATE		0x0400
+#define LOG_DIR_XTREE		0x0800	/* Xtree is in directory inode */
+
+/* UPDATEMAP log record descriptor type */
+#define	LOG_ALLOCXADLIST	0x0080
+#define	LOG_ALLOCPXDLIST	0x0040
+#define	LOG_ALLOCXAD		0x0020
+#define	LOG_ALLOCPXD		0x0010
+#define	LOG_FREEXADLIST		0x0008
+#define	LOG_FREEPXDLIST		0x0004
+#define	LOG_FREEXAD		0x0002
+#define	LOG_FREEPXD		0x0001
+
+
+struct lrd {
+	/*
+	 * type independent area
+	 */
+	__le32 logtid;		/* 4: log transaction identifier */
+	__le32 backchain;	/* 4: ptr to prev record of same transaction */
+	__le16 type;		/* 2: record type */
+	__le16 length;		/* 2: length of data in record (in byte) */
+	__le32 aggregate;	/* 4: file system lv/aggregate */
+	/* (16) */
+
+	/*
+	 * type dependent area (20)
+	 */
+	union {
+
+		/*
+		 *	COMMIT: commit
+		 *
+		 * transaction commit: no type-dependent information;
+		 */
+
+		/*
+		 *	REDOPAGE: after-image
+		 *
+		 * apply after-image;
+		 *
+		 * N.B. REDOPAGE, NOREDOPAGE, and UPDATEMAP must be same format;
+		 */
+		struct {
+			__le32 fileset;	/* 4: fileset number */
+			__le32 inode;	/* 4: inode number */
+			__le16 type;	/* 2: REDOPAGE record type */
+			__le16 l2linesize;	/* 2: log2 of line size */
+			pxd_t pxd;	/* 8: on-disk page pxd */
+		} redopage;	/* (20) */
+
+		/*
+		 *	NOREDOPAGE: the page is freed
+		 *
+		 * do not apply after-image records which precede this record
+		 * in the log with the same page block number to this page.
+		 *
+		 * N.B. REDOPAGE, NOREDOPAGE, and UPDATEMAP must be same format;
+		 */
+		struct {
+			__le32 fileset;	/* 4: fileset number */
+			__le32 inode;	/* 4: inode number */
+			__le16 type;	/* 2: NOREDOPAGE record type */
+			__le16 rsrvd;	/* 2: reserved */
+			pxd_t pxd;	/* 8: on-disk page pxd */
+		} noredopage;	/* (20) */
+
+		/*
+		 *	UPDATEMAP: update block allocation map
+		 *
+		 * either in-line PXD,
+		 * or     out-of-line  XADLIST;
+		 *
+		 * N.B. REDOPAGE, NOREDOPAGE, and UPDATEMAP must be same format;
+		 */
+		struct {
+			__le32 fileset;	/* 4: fileset number */
+			__le32 inode;	/* 4: inode number */
+			__le16 type;	/* 2: UPDATEMAP record type */
+			__le16 nxd;	/* 2: number of extents */
+			pxd_t pxd;	/* 8: pxd */
+		} updatemap;	/* (20) */
+
+		/*
+		 *	NOREDOINOEXT: the inode extent is freed
+		 *
+		 * do not apply after-image records which precede this
+		 * record in the log with the any of the 4 page block
+		 * numbers in this inode extent.
+		 *
+		 * NOTE: The fileset and pxd fields MUST remain in
+		 *       the same fields in the REDOPAGE record format.
+		 *
+		 */
+		struct {
+			__le32 fileset;	/* 4: fileset number */
+			__le32 iagnum;	/* 4: IAG number     */
+			__le32 inoext_idx;	/* 4: inode extent index */
+			pxd_t pxd;	/* 8: on-disk page pxd */
+		} noredoinoext;	/* (20) */
+
+		/*
+		 *	SYNCPT: log sync point
+		 *
+		 * replay log up to syncpt address specified;
+		 */
+		struct {
+			__le32 sync;	/* 4: syncpt address (0 = here) */
+		} syncpt;
+
+		/*
+		 *	MOUNT: file system mount
+		 *
+		 * file system mount: no type-dependent information;
+		 */
+
+		/*
+		 *	? FREEXTENT: free specified extent(s)
+		 *
+		 * free specified extent(s) from block allocation map
+		 * N.B.: nextents should be length of data/sizeof(xad_t)
+		 */
+		struct {
+			__le32 type;	/* 4: FREEXTENT record type */
+			__le32 nextent;	/* 4: number of extents */
+
+			/* data: PXD or XAD list */
+		} freextent;
+
+		/*
+		 *	? NOREDOFILE: this file is freed
+		 *
+		 * do not apply records which precede this record in the log
+		 * with the same inode number.
+		 *
+		 * NOREDOFILE must be the first to be written at commit
+		 * (last to be read in logredo()) - it prevents
+		 * replay of preceding updates of all preceding generations
+		 * of the inumber esp. the on-disk inode itself.
+		 */
+		struct {
+			__le32 fileset;	/* 4: fileset number */
+			__le32 inode;	/* 4: inode number */
+		} noredofile;
+
+		/*
+		 *	? NEWPAGE:
+		 *
+		 * metadata type dependent
+		 */
+		struct {
+			__le32 fileset;	/* 4: fileset number */
+			__le32 inode;	/* 4: inode number */
+			__le32 type;	/* 4: NEWPAGE record type */
+			pxd_t pxd;	/* 8: on-disk page pxd */
+		} newpage;
+
+		/*
+		 *	? DUMMY: filler
+		 *
+		 * no type-dependent information
+		 */
+	} log;
+};					/* (36) */
+
+#define	LOGRDSIZE	(sizeof(struct lrd))
+
+/*
+ *	line vector descriptor
+ */
+struct lvd {
+	__le16 offset;
+	__le16 length;
+};
+
+
+/*
+ *	log logical volume
+ */
+struct jfs_log {
+
+	struct list_head sb_list;/*  This is used to sync metadata
+				 *    before writing syncpt.
+				 */
+	struct list_head journal_list; /* Global list */
+	struct block_device *bdev; /* 4: log lv pointer */
+	int serial;		/* 4: log mount serial number */
+
+	s64 base;		/* @8: log extent address (inline log ) */
+	int size;		/* 4: log size in log page (in page) */
+	int l2bsize;		/* 4: log2 of bsize */
+
+	unsigned long flag;	/* 4: flag */
+
+	struct lbuf *lbuf_free;	/* 4: free lbufs */
+	wait_queue_head_t free_wait;	/* 4: */
+
+	/* log write */
+	int logtid;		/* 4: log tid */
+	int page;		/* 4: page number of eol page */
+	int eor;		/* 4: eor of last record in eol page */
+	struct lbuf *bp;	/* 4: current log page buffer */
+
+	struct mutex loglock;	/* 4: log write serialization lock */
+
+	/* syncpt */
+	int nextsync;		/* 4: bytes to write before next syncpt */
+	int active;		/* 4: */
+	wait_queue_head_t syncwait;	/* 4: */
+
+	/* commit */
+	uint cflag;		/* 4: */
+	struct list_head cqueue; /* FIFO commit queue */
+	struct tblock *flush_tblk; /* tblk we're waiting on for flush */
+	int gcrtc;		/* 4: GC_READY transaction count */
+	struct tblock *gclrt;	/* 4: latest GC_READY transaction */
+	spinlock_t gclock;	/* 4: group commit lock */
+	int logsize;		/* 4: log data area size in byte */
+	int lsn;		/* 4: end-of-log */
+	int clsn;		/* 4: clsn */
+	int syncpt;		/* 4: addr of last syncpt record */
+	int sync;		/* 4: addr from last logsync() */
+	struct list_head synclist;	/* 8: logsynclist anchor */
+	spinlock_t synclock;	/* 4: synclist lock */
+	struct lbuf *wqueue;	/* 4: log pageout queue */
+	int count;		/* 4: count */
+	uuid_t uuid;		/* 16: 128-bit uuid of log device */
+
+	int no_integrity;	/* 3: flag to disable journaling to disk */
+};
+
+/*
+ * Log flag
+ */
+#define log_INLINELOG	1
+#define log_SYNCBARRIER	2
+#define log_QUIESCE	3
+#define log_FLUSH	4
+
+/*
+ * group commit flag
+ */
+/* jfs_log */
+#define logGC_PAGEOUT	0x00000001
+
+/* tblock/lbuf */
+#define tblkGC_QUEUE		0x0001
+#define tblkGC_READY		0x0002
+#define tblkGC_COMMIT		0x0004
+#define tblkGC_COMMITTED	0x0008
+#define tblkGC_EOP		0x0010
+#define tblkGC_FREE		0x0020
+#define tblkGC_LEADER		0x0040
+#define tblkGC_ERROR		0x0080
+#define tblkGC_LAZY		0x0100	// D230860
+#define tblkGC_UNLOCKED		0x0200	// D230860
+
+/*
+ *		log cache buffer header
+ */
+struct lbuf {
+	struct jfs_log *l_log;	/* 4: log associated with buffer */
+
+	/*
+	 * data buffer base area
+	 */
+	uint l_flag;		/* 4: pageout control flags */
+
+	struct lbuf *l_wqnext;	/* 4: write queue link */
+	struct lbuf *l_freelist;	/* 4: freelistlink */
+
+	int l_pn;		/* 4: log page number */
+	int l_eor;		/* 4: log record eor */
+	int l_ceor;		/* 4: committed log record eor */
+
+	s64 l_blkno;		/* 8: log page block number */
+	caddr_t l_ldata;	/* 4: data page */
+	struct page *l_page;	/* The page itself */
+	uint l_offset;		/* Offset of l_ldata within the page */
+
+	wait_queue_head_t l_ioevent;	/* 4: i/o done event */
+};
+
+/* Reuse l_freelist for redrive list */
+#define l_redrive_next l_freelist
+
+/*
+ *	logsynclist block
+ *
+ * common logsyncblk prefix for jbuf_t and tblock
+ */
+struct logsyncblk {
+	u16 xflag;		/* flags */
+	u16 flag;		/* only meaninful in tblock */
+	lid_t lid;		/* lock id */
+	s32 lsn;		/* log sequence number */
+	struct list_head synclist;	/* log sync list link */
+};
+
+/*
+ *	logsynclist serialization (per log)
+ */
+
+#define LOGSYNC_LOCK_INIT(log) spin_lock_init(&(log)->synclock)
+#define LOGSYNC_LOCK(log, flags) spin_lock_irqsave(&(log)->synclock, flags)
+#define LOGSYNC_UNLOCK(log, flags) \
+	spin_unlock_irqrestore(&(log)->synclock, flags)
+
+/* compute the difference in bytes of lsn from sync point */
+#define logdiff(diff, lsn, log)\
+{\
+	diff = (lsn) - (log)->syncpt;\
+	if (diff < 0)\
+		diff += (log)->logsize;\
+}
+
+extern int lmLogOpen(struct super_block *sb);
+extern int lmLogClose(struct super_block *sb);
+extern int lmLogShutdown(struct jfs_log * log);
+extern int lmLogInit(struct jfs_log * log);
+extern int lmLogFormat(struct jfs_log *log, s64 logAddress, int logSize);
+extern int lmGroupCommit(struct jfs_log *, struct tblock *);
+extern int jfsIOWait(void *);
+extern void jfs_flush_journal(struct jfs_log * log, int wait);
+extern void jfs_syncpt(struct jfs_log *log, int hard_sync);
+
+#endif				/* _H_JFS_LOGMGR */
diff --git a/fs/jfs/jfs_metapage.c b/fs/jfs/jfs_metapage.c
new file mode 100644
index 000000000..2e8461ce7
--- /dev/null
+++ b/fs/jfs/jfs_metapage.c
@@ -0,0 +1,817 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2005
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/bio.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/buffer_head.h>
+#include <linux/mempool.h>
+#include <linux/seq_file.h>
+#include <linux/writeback.h>
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_filsys.h"
+#include "jfs_metapage.h"
+#include "jfs_txnmgr.h"
+#include "jfs_debug.h"
+
+#ifdef CONFIG_JFS_STATISTICS
+static struct {
+	uint	pagealloc;	/* # of page allocations */
+	uint	pagefree;	/* # of page frees */
+	uint	lockwait;	/* # of sleeping lock_metapage() calls */
+} mpStat;
+#endif
+
+#define metapage_locked(mp) test_bit(META_locked, &(mp)->flag)
+#define trylock_metapage(mp) test_and_set_bit_lock(META_locked, &(mp)->flag)
+
+static inline void unlock_metapage(struct metapage *mp)
+{
+	clear_bit_unlock(META_locked, &mp->flag);
+	wake_up(&mp->wait);
+}
+
+static inline void __lock_metapage(struct metapage *mp)
+{
+	DECLARE_WAITQUEUE(wait, current);
+	INCREMENT(mpStat.lockwait);
+	add_wait_queue_exclusive(&mp->wait, &wait);
+	do {
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		if (metapage_locked(mp)) {
+			unlock_page(mp->page);
+			io_schedule();
+			lock_page(mp->page);
+		}
+	} while (trylock_metapage(mp));
+	__set_current_state(TASK_RUNNING);
+	remove_wait_queue(&mp->wait, &wait);
+}
+
+/*
+ * Must have mp->page locked
+ */
+static inline void lock_metapage(struct metapage *mp)
+{
+	if (trylock_metapage(mp))
+		__lock_metapage(mp);
+}
+
+#define METAPOOL_MIN_PAGES 32
+static struct kmem_cache *metapage_cache;
+static mempool_t *metapage_mempool;
+
+#define MPS_PER_PAGE (PAGE_SIZE >> L2PSIZE)
+
+#if MPS_PER_PAGE > 1
+
+struct meta_anchor {
+	int mp_count;
+	atomic_t io_count;
+	struct metapage *mp[MPS_PER_PAGE];
+};
+#define mp_anchor(page) ((struct meta_anchor *)page_private(page))
+
+static inline struct metapage *page_to_mp(struct page *page, int offset)
+{
+	if (!PagePrivate(page))
+		return NULL;
+	return mp_anchor(page)->mp[offset >> L2PSIZE];
+}
+
+static inline int insert_metapage(struct page *page, struct metapage *mp)
+{
+	struct meta_anchor *a;
+	int index;
+	int l2mp_blocks;	/* log2 blocks per metapage */
+
+	if (PagePrivate(page))
+		a = mp_anchor(page);
+	else {
+		a = kzalloc(sizeof(struct meta_anchor), GFP_NOFS);
+		if (!a)
+			return -ENOMEM;
+		set_page_private(page, (unsigned long)a);
+		SetPagePrivate(page);
+		kmap(page);
+	}
+
+	if (mp) {
+		l2mp_blocks = L2PSIZE - page->mapping->host->i_blkbits;
+		index = (mp->index >> l2mp_blocks) & (MPS_PER_PAGE - 1);
+		a->mp_count++;
+		a->mp[index] = mp;
+	}
+
+	return 0;
+}
+
+static inline void remove_metapage(struct page *page, struct metapage *mp)
+{
+	struct meta_anchor *a = mp_anchor(page);
+	int l2mp_blocks = L2PSIZE - page->mapping->host->i_blkbits;
+	int index;
+
+	index = (mp->index >> l2mp_blocks) & (MPS_PER_PAGE - 1);
+
+	BUG_ON(a->mp[index] != mp);
+
+	a->mp[index] = NULL;
+	if (--a->mp_count == 0) {
+		kfree(a);
+		set_page_private(page, 0);
+		ClearPagePrivate(page);
+		kunmap(page);
+	}
+}
+
+static inline void inc_io(struct page *page)
+{
+	atomic_inc(&mp_anchor(page)->io_count);
+}
+
+static inline void dec_io(struct page *page, void (*handler) (struct page *))
+{
+	if (atomic_dec_and_test(&mp_anchor(page)->io_count))
+		handler(page);
+}
+
+#else
+static inline struct metapage *page_to_mp(struct page *page, int offset)
+{
+	return PagePrivate(page) ? (struct metapage *)page_private(page) : NULL;
+}
+
+static inline int insert_metapage(struct page *page, struct metapage *mp)
+{
+	if (mp) {
+		set_page_private(page, (unsigned long)mp);
+		SetPagePrivate(page);
+		kmap(page);
+	}
+	return 0;
+}
+
+static inline void remove_metapage(struct page *page, struct metapage *mp)
+{
+	set_page_private(page, 0);
+	ClearPagePrivate(page);
+	kunmap(page);
+}
+
+#define inc_io(page) do {} while(0)
+#define dec_io(page, handler) handler(page)
+
+#endif
+
+static inline struct metapage *alloc_metapage(gfp_t gfp_mask)
+{
+	struct metapage *mp = mempool_alloc(metapage_mempool, gfp_mask);
+
+	if (mp) {
+		mp->lid = 0;
+		mp->lsn = 0;
+		mp->data = NULL;
+		mp->clsn = 0;
+		mp->log = NULL;
+		init_waitqueue_head(&mp->wait);
+	}
+	return mp;
+}
+
+static inline void free_metapage(struct metapage *mp)
+{
+	mempool_free(mp, metapage_mempool);
+}
+
+int __init metapage_init(void)
+{
+	/*
+	 * Allocate the metapage structures
+	 */
+	metapage_cache = kmem_cache_create("jfs_mp", sizeof(struct metapage),
+					   0, 0, NULL);
+	if (metapage_cache == NULL)
+		return -ENOMEM;
+
+	metapage_mempool = mempool_create_slab_pool(METAPOOL_MIN_PAGES,
+						    metapage_cache);
+
+	if (metapage_mempool == NULL) {
+		kmem_cache_destroy(metapage_cache);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+void metapage_exit(void)
+{
+	mempool_destroy(metapage_mempool);
+	kmem_cache_destroy(metapage_cache);
+}
+
+static inline void drop_metapage(struct page *page, struct metapage *mp)
+{
+	if (mp->count || mp->nohomeok || test_bit(META_dirty, &mp->flag) ||
+	    test_bit(META_io, &mp->flag))
+		return;
+	remove_metapage(page, mp);
+	INCREMENT(mpStat.pagefree);
+	free_metapage(mp);
+}
+
+/*
+ * Metapage address space operations
+ */
+
+static sector_t metapage_get_blocks(struct inode *inode, sector_t lblock,
+				    int *len)
+{
+	int rc = 0;
+	int xflag;
+	s64 xaddr;
+	sector_t file_blocks = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
+			       inode->i_blkbits;
+
+	if (lblock >= file_blocks)
+		return 0;
+	if (lblock + *len > file_blocks)
+		*len = file_blocks - lblock;
+
+	if (inode->i_ino) {
+		rc = xtLookup(inode, (s64)lblock, *len, &xflag, &xaddr, len, 0);
+		if ((rc == 0) && *len)
+			lblock = (sector_t)xaddr;
+		else
+			lblock = 0;
+	} /* else no mapping */
+
+	return lblock;
+}
+
+static void last_read_complete(struct page *page)
+{
+	if (!PageError(page))
+		SetPageUptodate(page);
+	unlock_page(page);
+}
+
+static void metapage_read_end_io(struct bio *bio)
+{
+	struct page *page = bio->bi_private;
+
+	if (bio->bi_status) {
+		printk(KERN_ERR "metapage_read_end_io: I/O error\n");
+		SetPageError(page);
+	}
+
+	dec_io(page, last_read_complete);
+	bio_put(bio);
+}
+
+static void remove_from_logsync(struct metapage *mp)
+{
+	struct jfs_log *log = mp->log;
+	unsigned long flags;
+/*
+ * This can race.  Recheck that log hasn't been set to null, and after
+ * acquiring logsync lock, recheck lsn
+ */
+	if (!log)
+		return;
+
+	LOGSYNC_LOCK(log, flags);
+	if (mp->lsn) {
+		mp->log = NULL;
+		mp->lsn = 0;
+		mp->clsn = 0;
+		log->count--;
+		list_del(&mp->synclist);
+	}
+	LOGSYNC_UNLOCK(log, flags);
+}
+
+static void last_write_complete(struct page *page)
+{
+	struct metapage *mp;
+	unsigned int offset;
+
+	for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
+		mp = page_to_mp(page, offset);
+		if (mp && test_bit(META_io, &mp->flag)) {
+			if (mp->lsn)
+				remove_from_logsync(mp);
+			clear_bit(META_io, &mp->flag);
+		}
+		/*
+		 * I'd like to call drop_metapage here, but I don't think it's
+		 * safe unless I have the page locked
+		 */
+	}
+	end_page_writeback(page);
+}
+
+static void metapage_write_end_io(struct bio *bio)
+{
+	struct page *page = bio->bi_private;
+
+	BUG_ON(!PagePrivate(page));
+
+	if (bio->bi_status) {
+		printk(KERN_ERR "metapage_write_end_io: I/O error\n");
+		SetPageError(page);
+	}
+	dec_io(page, last_write_complete);
+	bio_put(bio);
+}
+
+static int metapage_writepage(struct page *page, struct writeback_control *wbc)
+{
+	struct bio *bio = NULL;
+	int block_offset;	/* block offset of mp within page */
+	struct inode *inode = page->mapping->host;
+	int blocks_per_mp = JFS_SBI(inode->i_sb)->nbperpage;
+	int len;
+	int xlen;
+	struct metapage *mp;
+	int redirty = 0;
+	sector_t lblock;
+	int nr_underway = 0;
+	sector_t pblock;
+	sector_t next_block = 0;
+	sector_t page_start;
+	unsigned long bio_bytes = 0;
+	unsigned long bio_offset = 0;
+	int offset;
+	int bad_blocks = 0;
+
+	page_start = (sector_t)page->index <<
+		     (PAGE_SHIFT - inode->i_blkbits);
+	BUG_ON(!PageLocked(page));
+	BUG_ON(PageWriteback(page));
+	set_page_writeback(page);
+
+	for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
+		mp = page_to_mp(page, offset);
+
+		if (!mp || !test_bit(META_dirty, &mp->flag))
+			continue;
+
+		if (mp->nohomeok && !test_bit(META_forcewrite, &mp->flag)) {
+			redirty = 1;
+			/*
+			 * Make sure this page isn't blocked indefinitely.
+			 * If the journal isn't undergoing I/O, push it
+			 */
+			if (mp->log && !(mp->log->cflag & logGC_PAGEOUT))
+				jfs_flush_journal(mp->log, 0);
+			continue;
+		}
+
+		clear_bit(META_dirty, &mp->flag);
+		set_bit(META_io, &mp->flag);
+		block_offset = offset >> inode->i_blkbits;
+		lblock = page_start + block_offset;
+		if (bio) {
+			if (xlen && lblock == next_block) {
+				/* Contiguous, in memory & on disk */
+				len = min(xlen, blocks_per_mp);
+				xlen -= len;
+				bio_bytes += len << inode->i_blkbits;
+				continue;
+			}
+			/* Not contiguous */
+			if (bio_add_page(bio, page, bio_bytes, bio_offset) <
+			    bio_bytes)
+				goto add_failed;
+			/*
+			 * Increment counter before submitting i/o to keep
+			 * count from hitting zero before we're through
+			 */
+			inc_io(page);
+			if (!bio->bi_iter.bi_size)
+				goto dump_bio;
+			submit_bio(bio);
+			nr_underway++;
+			bio = NULL;
+		} else
+			inc_io(page);
+		xlen = (PAGE_SIZE - offset) >> inode->i_blkbits;
+		pblock = metapage_get_blocks(inode, lblock, &xlen);
+		if (!pblock) {
+			printk(KERN_ERR "JFS: metapage_get_blocks failed\n");
+			/*
+			 * We already called inc_io(), but can't cancel it
+			 * with dec_io() until we're done with the page
+			 */
+			bad_blocks++;
+			continue;
+		}
+		len = min(xlen, (int)JFS_SBI(inode->i_sb)->nbperpage);
+
+		bio = bio_alloc(inode->i_sb->s_bdev, 1, REQ_OP_WRITE, GFP_NOFS);
+		bio->bi_iter.bi_sector = pblock << (inode->i_blkbits - 9);
+		bio->bi_end_io = metapage_write_end_io;
+		bio->bi_private = page;
+
+		/* Don't call bio_add_page yet, we may add to this vec */
+		bio_offset = offset;
+		bio_bytes = len << inode->i_blkbits;
+
+		xlen -= len;
+		next_block = lblock + len;
+	}
+	if (bio) {
+		if (bio_add_page(bio, page, bio_bytes, bio_offset) < bio_bytes)
+				goto add_failed;
+		if (!bio->bi_iter.bi_size)
+			goto dump_bio;
+
+		submit_bio(bio);
+		nr_underway++;
+	}
+	if (redirty)
+		redirty_page_for_writepage(wbc, page);
+
+	unlock_page(page);
+
+	if (bad_blocks)
+		goto err_out;
+
+	if (nr_underway == 0)
+		end_page_writeback(page);
+
+	return 0;
+add_failed:
+	/* We should never reach here, since we're only adding one vec */
+	printk(KERN_ERR "JFS: bio_add_page failed unexpectedly\n");
+	goto skip;
+dump_bio:
+	print_hex_dump(KERN_ERR, "JFS: dump of bio: ", DUMP_PREFIX_ADDRESS, 16,
+		       4, bio, sizeof(*bio), 0);
+skip:
+	bio_put(bio);
+	unlock_page(page);
+	dec_io(page, last_write_complete);
+err_out:
+	while (bad_blocks--)
+		dec_io(page, last_write_complete);
+	return -EIO;
+}
+
+static int metapage_read_folio(struct file *fp, struct folio *folio)
+{
+	struct page *page = &folio->page;
+	struct inode *inode = page->mapping->host;
+	struct bio *bio = NULL;
+	int block_offset;
+	int blocks_per_page = i_blocks_per_page(inode, page);
+	sector_t page_start;	/* address of page in fs blocks */
+	sector_t pblock;
+	int xlen;
+	unsigned int len;
+	int offset;
+
+	BUG_ON(!PageLocked(page));
+	page_start = (sector_t)page->index <<
+		     (PAGE_SHIFT - inode->i_blkbits);
+
+	block_offset = 0;
+	while (block_offset < blocks_per_page) {
+		xlen = blocks_per_page - block_offset;
+		pblock = metapage_get_blocks(inode, page_start + block_offset,
+					     &xlen);
+		if (pblock) {
+			if (!PagePrivate(page))
+				insert_metapage(page, NULL);
+			inc_io(page);
+			if (bio)
+				submit_bio(bio);
+
+			bio = bio_alloc(inode->i_sb->s_bdev, 1, REQ_OP_READ,
+					GFP_NOFS);
+			bio->bi_iter.bi_sector =
+				pblock << (inode->i_blkbits - 9);
+			bio->bi_end_io = metapage_read_end_io;
+			bio->bi_private = page;
+			len = xlen << inode->i_blkbits;
+			offset = block_offset << inode->i_blkbits;
+			if (bio_add_page(bio, page, len, offset) < len)
+				goto add_failed;
+			block_offset += xlen;
+		} else
+			block_offset++;
+	}
+	if (bio)
+		submit_bio(bio);
+	else
+		unlock_page(page);
+
+	return 0;
+
+add_failed:
+	printk(KERN_ERR "JFS: bio_add_page failed unexpectedly\n");
+	bio_put(bio);
+	dec_io(page, last_read_complete);
+	return -EIO;
+}
+
+static bool metapage_release_folio(struct folio *folio, gfp_t gfp_mask)
+{
+	struct metapage *mp;
+	bool ret = true;
+	int offset;
+
+	for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
+		mp = page_to_mp(&folio->page, offset);
+
+		if (!mp)
+			continue;
+
+		jfs_info("metapage_release_folio: mp = 0x%p", mp);
+		if (mp->count || mp->nohomeok ||
+		    test_bit(META_dirty, &mp->flag)) {
+			jfs_info("count = %ld, nohomeok = %d", mp->count,
+				 mp->nohomeok);
+			ret = false;
+			continue;
+		}
+		if (mp->lsn)
+			remove_from_logsync(mp);
+		remove_metapage(&folio->page, mp);
+		INCREMENT(mpStat.pagefree);
+		free_metapage(mp);
+	}
+	return ret;
+}
+
+static void metapage_invalidate_folio(struct folio *folio, size_t offset,
+				    size_t length)
+{
+	BUG_ON(offset || length < folio_size(folio));
+
+	BUG_ON(folio_test_writeback(folio));
+
+	metapage_release_folio(folio, 0);
+}
+
+const struct address_space_operations jfs_metapage_aops = {
+	.read_folio	= metapage_read_folio,
+	.writepage	= metapage_writepage,
+	.release_folio	= metapage_release_folio,
+	.invalidate_folio = metapage_invalidate_folio,
+	.dirty_folio	= filemap_dirty_folio,
+};
+
+struct metapage *__get_metapage(struct inode *inode, unsigned long lblock,
+				unsigned int size, int absolute,
+				unsigned long new)
+{
+	int l2BlocksPerPage;
+	int l2bsize;
+	struct address_space *mapping;
+	struct metapage *mp = NULL;
+	struct page *page;
+	unsigned long page_index;
+	unsigned long page_offset;
+
+	jfs_info("__get_metapage: ino = %ld, lblock = 0x%lx, abs=%d",
+		 inode->i_ino, lblock, absolute);
+
+	l2bsize = inode->i_blkbits;
+	l2BlocksPerPage = PAGE_SHIFT - l2bsize;
+	page_index = lblock >> l2BlocksPerPage;
+	page_offset = (lblock - (page_index << l2BlocksPerPage)) << l2bsize;
+	if ((page_offset + size) > PAGE_SIZE) {
+		jfs_err("MetaData crosses page boundary!!");
+		jfs_err("lblock = %lx, size  = %d", lblock, size);
+		dump_stack();
+		return NULL;
+	}
+	if (absolute)
+		mapping = JFS_SBI(inode->i_sb)->direct_inode->i_mapping;
+	else {
+		/*
+		 * If an nfs client tries to read an inode that is larger
+		 * than any existing inodes, we may try to read past the
+		 * end of the inode map
+		 */
+		if ((lblock << inode->i_blkbits) >= inode->i_size)
+			return NULL;
+		mapping = inode->i_mapping;
+	}
+
+	if (new && (PSIZE == PAGE_SIZE)) {
+		page = grab_cache_page(mapping, page_index);
+		if (!page) {
+			jfs_err("grab_cache_page failed!");
+			return NULL;
+		}
+		SetPageUptodate(page);
+	} else {
+		page = read_mapping_page(mapping, page_index, NULL);
+		if (IS_ERR(page)) {
+			jfs_err("read_mapping_page failed!");
+			return NULL;
+		}
+		lock_page(page);
+	}
+
+	mp = page_to_mp(page, page_offset);
+	if (mp) {
+		if (mp->logical_size != size) {
+			jfs_error(inode->i_sb,
+				  "get_mp->logical_size != size\n");
+			jfs_err("logical_size = %d, size = %d",
+				mp->logical_size, size);
+			dump_stack();
+			goto unlock;
+		}
+		mp->count++;
+		lock_metapage(mp);
+		if (test_bit(META_discard, &mp->flag)) {
+			if (!new) {
+				jfs_error(inode->i_sb,
+					  "using a discarded metapage\n");
+				discard_metapage(mp);
+				goto unlock;
+			}
+			clear_bit(META_discard, &mp->flag);
+		}
+	} else {
+		INCREMENT(mpStat.pagealloc);
+		mp = alloc_metapage(GFP_NOFS);
+		if (!mp)
+			goto unlock;
+		mp->page = page;
+		mp->sb = inode->i_sb;
+		mp->flag = 0;
+		mp->xflag = COMMIT_PAGE;
+		mp->count = 1;
+		mp->nohomeok = 0;
+		mp->logical_size = size;
+		mp->data = page_address(page) + page_offset;
+		mp->index = lblock;
+		if (unlikely(insert_metapage(page, mp))) {
+			free_metapage(mp);
+			goto unlock;
+		}
+		lock_metapage(mp);
+	}
+
+	if (new) {
+		jfs_info("zeroing mp = 0x%p", mp);
+		memset(mp->data, 0, PSIZE);
+	}
+
+	unlock_page(page);
+	jfs_info("__get_metapage: returning = 0x%p data = 0x%p", mp, mp->data);
+	return mp;
+
+unlock:
+	unlock_page(page);
+	return NULL;
+}
+
+void grab_metapage(struct metapage * mp)
+{
+	jfs_info("grab_metapage: mp = 0x%p", mp);
+	get_page(mp->page);
+	lock_page(mp->page);
+	mp->count++;
+	lock_metapage(mp);
+	unlock_page(mp->page);
+}
+
+void force_metapage(struct metapage *mp)
+{
+	struct page *page = mp->page;
+	jfs_info("force_metapage: mp = 0x%p", mp);
+	set_bit(META_forcewrite, &mp->flag);
+	clear_bit(META_sync, &mp->flag);
+	get_page(page);
+	lock_page(page);
+	set_page_dirty(page);
+	if (write_one_page(page))
+		jfs_error(mp->sb, "write_one_page() failed\n");
+	clear_bit(META_forcewrite, &mp->flag);
+	put_page(page);
+}
+
+void hold_metapage(struct metapage *mp)
+{
+	lock_page(mp->page);
+}
+
+void put_metapage(struct metapage *mp)
+{
+	if (mp->count || mp->nohomeok) {
+		/* Someone else will release this */
+		unlock_page(mp->page);
+		return;
+	}
+	get_page(mp->page);
+	mp->count++;
+	lock_metapage(mp);
+	unlock_page(mp->page);
+	release_metapage(mp);
+}
+
+void release_metapage(struct metapage * mp)
+{
+	struct page *page = mp->page;
+	jfs_info("release_metapage: mp = 0x%p, flag = 0x%lx", mp, mp->flag);
+
+	BUG_ON(!page);
+
+	lock_page(page);
+	unlock_metapage(mp);
+
+	assert(mp->count);
+	if (--mp->count || mp->nohomeok) {
+		unlock_page(page);
+		put_page(page);
+		return;
+	}
+
+	if (test_bit(META_dirty, &mp->flag)) {
+		set_page_dirty(page);
+		if (test_bit(META_sync, &mp->flag)) {
+			clear_bit(META_sync, &mp->flag);
+			if (write_one_page(page))
+				jfs_error(mp->sb, "write_one_page() failed\n");
+			lock_page(page); /* write_one_page unlocks the page */
+		}
+	} else if (mp->lsn)	/* discard_metapage doesn't remove it */
+		remove_from_logsync(mp);
+
+	/* Try to keep metapages from using up too much memory */
+	drop_metapage(page, mp);
+
+	unlock_page(page);
+	put_page(page);
+}
+
+void __invalidate_metapages(struct inode *ip, s64 addr, int len)
+{
+	sector_t lblock;
+	int l2BlocksPerPage = PAGE_SHIFT - ip->i_blkbits;
+	int BlocksPerPage = 1 << l2BlocksPerPage;
+	/* All callers are interested in block device's mapping */
+	struct address_space *mapping =
+		JFS_SBI(ip->i_sb)->direct_inode->i_mapping;
+	struct metapage *mp;
+	struct page *page;
+	unsigned int offset;
+
+	/*
+	 * Mark metapages to discard.  They will eventually be
+	 * released, but should not be written.
+	 */
+	for (lblock = addr & ~(BlocksPerPage - 1); lblock < addr + len;
+	     lblock += BlocksPerPage) {
+		page = find_lock_page(mapping, lblock >> l2BlocksPerPage);
+		if (!page)
+			continue;
+		for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
+			mp = page_to_mp(page, offset);
+			if (!mp)
+				continue;
+			if (mp->index < addr)
+				continue;
+			if (mp->index >= addr + len)
+				break;
+
+			clear_bit(META_dirty, &mp->flag);
+			set_bit(META_discard, &mp->flag);
+			if (mp->lsn)
+				remove_from_logsync(mp);
+		}
+		unlock_page(page);
+		put_page(page);
+	}
+}
+
+#ifdef CONFIG_JFS_STATISTICS
+int jfs_mpstat_proc_show(struct seq_file *m, void *v)
+{
+	seq_printf(m,
+		       "JFS Metapage statistics\n"
+		       "=======================\n"
+		       "page allocations = %d\n"
+		       "page frees = %d\n"
+		       "lock waits = %d\n",
+		       mpStat.pagealloc,
+		       mpStat.pagefree,
+		       mpStat.lockwait);
+	return 0;
+}
+#endif
diff --git a/fs/jfs/jfs_metapage.h b/fs/jfs/jfs_metapage.h
new file mode 100644
index 000000000..4179f9df4
--- /dev/null
+++ b/fs/jfs/jfs_metapage.h
@@ -0,0 +1,142 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+#ifndef	_H_JFS_METAPAGE
+#define _H_JFS_METAPAGE
+
+#include <linux/pagemap.h>
+
+struct metapage {
+	/* Common logsyncblk prefix (see jfs_logmgr.h) */
+	u16 xflag;
+	u16 unused;
+	lid_t lid;
+	int lsn;
+	struct list_head synclist;
+	/* End of logsyncblk prefix */
+
+	unsigned long flag;	/* See Below */
+	unsigned long count;	/* Reference count */
+	void *data;		/* Data pointer */
+	sector_t index;		/* block address of page */
+	wait_queue_head_t wait;
+
+	/* implementation */
+	struct page *page;
+	struct super_block *sb;
+	unsigned int logical_size;
+
+	/* Journal management */
+	int clsn;
+	int nohomeok;
+	struct jfs_log *log;
+};
+
+/* metapage flag */
+#define META_locked	0
+#define META_dirty	2
+#define META_sync	3
+#define META_discard	4
+#define META_forcewrite	5
+#define META_io		6
+
+#define mark_metapage_dirty(mp) set_bit(META_dirty, &(mp)->flag)
+
+/* function prototypes */
+extern int metapage_init(void);
+extern void metapage_exit(void);
+extern struct metapage *__get_metapage(struct inode *inode,
+				  unsigned long lblock, unsigned int size,
+				  int absolute, unsigned long new);
+
+#define read_metapage(inode, lblock, size, absolute)\
+	 __get_metapage(inode, lblock, size, absolute, false)
+
+#define get_metapage(inode, lblock, size, absolute)\
+	 __get_metapage(inode, lblock, size, absolute, true)
+
+extern void release_metapage(struct metapage *);
+extern void grab_metapage(struct metapage *);
+extern void force_metapage(struct metapage *);
+
+/*
+ * hold_metapage and put_metapage are used in conjunction.  The page lock
+ * is not dropped between the two, so no other threads can get or release
+ * the metapage
+ */
+extern void hold_metapage(struct metapage *);
+extern void put_metapage(struct metapage *);
+
+static inline void write_metapage(struct metapage *mp)
+{
+	set_bit(META_dirty, &mp->flag);
+	release_metapage(mp);
+}
+
+static inline void flush_metapage(struct metapage *mp)
+{
+	set_bit(META_sync, &mp->flag);
+	write_metapage(mp);
+}
+
+static inline void discard_metapage(struct metapage *mp)
+{
+	clear_bit(META_dirty, &mp->flag);
+	set_bit(META_discard, &mp->flag);
+	release_metapage(mp);
+}
+
+static inline void metapage_nohomeok(struct metapage *mp)
+{
+	struct page *page = mp->page;
+	lock_page(page);
+	if (!mp->nohomeok++) {
+		mark_metapage_dirty(mp);
+		get_page(page);
+		wait_on_page_writeback(page);
+	}
+	unlock_page(page);
+}
+
+/*
+ * This serializes access to mp->lsn when metapages are added to logsynclist
+ * without setting nohomeok.  i.e. updating imap & dmap
+ */
+static inline void metapage_wait_for_io(struct metapage *mp)
+{
+	if (test_bit(META_io, &mp->flag))
+		wait_on_page_writeback(mp->page);
+}
+
+/*
+ * This is called when already holding the metapage
+ */
+static inline void _metapage_homeok(struct metapage *mp)
+{
+	if (!--mp->nohomeok)
+		put_page(mp->page);
+}
+
+static inline void metapage_homeok(struct metapage *mp)
+{
+	hold_metapage(mp);
+	_metapage_homeok(mp);
+	put_metapage(mp);
+}
+
+extern const struct address_space_operations jfs_metapage_aops;
+
+/*
+ * This routines invalidate all pages for an extent.
+ */
+extern void __invalidate_metapages(struct inode *, s64, int);
+#define invalidate_pxd_metapages(ip, pxd) \
+	__invalidate_metapages((ip), addressPXD(&(pxd)), lengthPXD(&(pxd)))
+#define invalidate_dxd_metapages(ip, dxd) \
+	__invalidate_metapages((ip), addressDXD(&(dxd)), lengthDXD(&(dxd)))
+#define invalidate_xad_metapages(ip, xad) \
+	__invalidate_metapages((ip), addressXAD(&(xad)), lengthXAD(&(xad)))
+
+#endif				/* _H_JFS_METAPAGE */
diff --git a/fs/jfs/jfs_mount.c b/fs/jfs/jfs_mount.c
new file mode 100644
index 000000000..48d1f70f7
--- /dev/null
+++ b/fs/jfs/jfs_mount.c
@@ -0,0 +1,496 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+
+/*
+ * Module: jfs_mount.c
+ *
+ * note: file system in transition to aggregate/fileset:
+ *
+ * file system mount is interpreted as the mount of aggregate,
+ * if not already mounted, and mount of the single/only fileset in
+ * the aggregate;
+ *
+ * a file system/aggregate is represented by an internal inode
+ * (aka mount inode) initialized with aggregate superblock;
+ * each vfs represents a fileset, and points to its "fileset inode
+ * allocation map inode" (aka fileset inode):
+ * (an aggregate itself is structured recursively as a filset:
+ * an internal vfs is constructed and points to its "fileset inode
+ * allocation map inode" (aka aggregate inode) where each inode
+ * represents a fileset inode) so that inode number is mapped to
+ * on-disk inode in uniform way at both aggregate and fileset level;
+ *
+ * each vnode/inode of a fileset is linked to its vfs (to facilitate
+ * per fileset inode operations, e.g., unmount of a fileset, etc.);
+ * each inode points to the mount inode (to facilitate access to
+ * per aggregate information, e.g., block size, etc.) as well as
+ * its file set inode.
+ *
+ *   aggregate
+ *   ipmnt
+ *   mntvfs -> fileset ipimap+ -> aggregate ipbmap -> aggregate ipaimap;
+ *             fileset vfs     -> vp(1) <-> ... <-> vp(n) <->vproot;
+ */
+
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include <linux/blkdev.h>
+#include <linux/log2.h>
+
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_superblock.h"
+#include "jfs_dmap.h"
+#include "jfs_imap.h"
+#include "jfs_metapage.h"
+#include "jfs_debug.h"
+
+
+/*
+ * forward references
+ */
+static int chkSuper(struct super_block *);
+static int logMOUNT(struct super_block *sb);
+
+/*
+ * NAME:	jfs_mount(sb)
+ *
+ * FUNCTION:	vfs_mount()
+ *
+ * PARAMETER:	sb	- super block
+ *
+ * RETURN:	-EBUSY	- device already mounted or open for write
+ *		-EBUSY	- cvrdvp already mounted;
+ *		-EBUSY	- mount table full
+ *		-ENOTDIR- cvrdvp not directory on a device mount
+ *		-ENXIO	- device open failure
+ */
+int jfs_mount(struct super_block *sb)
+{
+	int rc = 0;		/* Return code */
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct inode *ipaimap = NULL;
+	struct inode *ipaimap2 = NULL;
+	struct inode *ipimap = NULL;
+	struct inode *ipbmap = NULL;
+
+	/*
+	 * read/validate superblock
+	 * (initialize mount inode from the superblock)
+	 */
+	if ((rc = chkSuper(sb))) {
+		goto out;
+	}
+
+	ipaimap = diReadSpecial(sb, AGGREGATE_I, 0);
+	if (ipaimap == NULL) {
+		jfs_err("jfs_mount: Failed to read AGGREGATE_I");
+		rc = -EIO;
+		goto out;
+	}
+	sbi->ipaimap = ipaimap;
+
+	jfs_info("jfs_mount: ipaimap:0x%p", ipaimap);
+
+	/*
+	 * initialize aggregate inode allocation map
+	 */
+	if ((rc = diMount(ipaimap))) {
+		jfs_err("jfs_mount: diMount(ipaimap) failed w/rc = %d", rc);
+		goto err_ipaimap;
+	}
+
+	/*
+	 * open aggregate block allocation map
+	 */
+	ipbmap = diReadSpecial(sb, BMAP_I, 0);
+	if (ipbmap == NULL) {
+		rc = -EIO;
+		goto err_umount_ipaimap;
+	}
+
+	jfs_info("jfs_mount: ipbmap:0x%p", ipbmap);
+
+	sbi->ipbmap = ipbmap;
+
+	/*
+	 * initialize aggregate block allocation map
+	 */
+	if ((rc = dbMount(ipbmap))) {
+		jfs_err("jfs_mount: dbMount failed w/rc = %d", rc);
+		goto err_ipbmap;
+	}
+
+	/*
+	 * open the secondary aggregate inode allocation map
+	 *
+	 * This is a duplicate of the aggregate inode allocation map.
+	 *
+	 * hand craft a vfs in the same fashion as we did to read ipaimap.
+	 * By adding INOSPEREXT (32) to the inode number, we are telling
+	 * diReadSpecial that we are reading from the secondary aggregate
+	 * inode table.  This also creates a unique entry in the inode hash
+	 * table.
+	 */
+	if ((sbi->mntflag & JFS_BAD_SAIT) == 0) {
+		ipaimap2 = diReadSpecial(sb, AGGREGATE_I, 1);
+		if (!ipaimap2) {
+			jfs_err("jfs_mount: Failed to read AGGREGATE_I");
+			rc = -EIO;
+			goto err_umount_ipbmap;
+		}
+		sbi->ipaimap2 = ipaimap2;
+
+		jfs_info("jfs_mount: ipaimap2:0x%p", ipaimap2);
+
+		/*
+		 * initialize secondary aggregate inode allocation map
+		 */
+		if ((rc = diMount(ipaimap2))) {
+			jfs_err("jfs_mount: diMount(ipaimap2) failed, rc = %d",
+				rc);
+			goto err_ipaimap2;
+		}
+	} else
+		/* Secondary aggregate inode table is not valid */
+		sbi->ipaimap2 = NULL;
+
+	/*
+	 *	mount (the only/single) fileset
+	 */
+	/*
+	 * open fileset inode allocation map (aka fileset inode)
+	 */
+	ipimap = diReadSpecial(sb, FILESYSTEM_I, 0);
+	if (ipimap == NULL) {
+		jfs_err("jfs_mount: Failed to read FILESYSTEM_I");
+		/* open fileset secondary inode allocation map */
+		rc = -EIO;
+		goto err_umount_ipaimap2;
+	}
+	jfs_info("jfs_mount: ipimap:0x%p", ipimap);
+
+	/* map further access of per fileset inodes by the fileset inode */
+	sbi->ipimap = ipimap;
+
+	/* initialize fileset inode allocation map */
+	if ((rc = diMount(ipimap))) {
+		jfs_err("jfs_mount: diMount failed w/rc = %d", rc);
+		goto err_ipimap;
+	}
+
+	return rc;
+
+	/*
+	 *	unwind on error
+	 */
+err_ipimap:
+	/* close fileset inode allocation map inode */
+	diFreeSpecial(ipimap);
+err_umount_ipaimap2:
+	/* close secondary aggregate inode allocation map */
+	if (ipaimap2)
+		diUnmount(ipaimap2, 1);
+err_ipaimap2:
+	/* close aggregate inodes */
+	if (ipaimap2)
+		diFreeSpecial(ipaimap2);
+err_umount_ipbmap:	/* close aggregate block allocation map */
+	dbUnmount(ipbmap, 1);
+err_ipbmap:		/* close aggregate inodes */
+	diFreeSpecial(ipbmap);
+err_umount_ipaimap:	/* close aggregate inode allocation map */
+	diUnmount(ipaimap, 1);
+err_ipaimap:		/* close aggregate inodes */
+	diFreeSpecial(ipaimap);
+out:
+	if (rc)
+		jfs_err("Mount JFS Failure: %d", rc);
+
+	return rc;
+}
+
+/*
+ * NAME:	jfs_mount_rw(sb, remount)
+ *
+ * FUNCTION:	Completes read-write mount, or remounts read-only volume
+ *		as read-write
+ */
+int jfs_mount_rw(struct super_block *sb, int remount)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	int rc;
+
+	/*
+	 * If we are re-mounting a previously read-only volume, we want to
+	 * re-read the inode and block maps, since fsck.jfs may have updated
+	 * them.
+	 */
+	if (remount) {
+		if (chkSuper(sb) || (sbi->state != FM_CLEAN))
+			return -EINVAL;
+
+		truncate_inode_pages(sbi->ipimap->i_mapping, 0);
+		truncate_inode_pages(sbi->ipbmap->i_mapping, 0);
+		diUnmount(sbi->ipimap, 1);
+		if ((rc = diMount(sbi->ipimap))) {
+			jfs_err("jfs_mount_rw: diMount failed!");
+			return rc;
+		}
+
+		dbUnmount(sbi->ipbmap, 1);
+		if ((rc = dbMount(sbi->ipbmap))) {
+			jfs_err("jfs_mount_rw: dbMount failed!");
+			return rc;
+		}
+	}
+
+	/*
+	 * open/initialize log
+	 */
+	if ((rc = lmLogOpen(sb)))
+		return rc;
+
+	/*
+	 * update file system superblock;
+	 */
+	if ((rc = updateSuper(sb, FM_MOUNT))) {
+		jfs_err("jfs_mount: updateSuper failed w/rc = %d", rc);
+		lmLogClose(sb);
+		return rc;
+	}
+
+	/*
+	 * write MOUNT log record of the file system
+	 */
+	logMOUNT(sb);
+
+	return rc;
+}
+
+/*
+ *	chkSuper()
+ *
+ * validate the superblock of the file system to be mounted and
+ * get the file system parameters.
+ *
+ * returns
+ *	0 with fragsize set if check successful
+ *	error code if not successful
+ */
+static int chkSuper(struct super_block *sb)
+{
+	int rc = 0;
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct jfs_superblock *j_sb;
+	struct buffer_head *bh;
+	int AIM_bytesize, AIT_bytesize;
+	int expected_AIM_bytesize, expected_AIT_bytesize;
+	s64 AIM_byte_addr, AIT_byte_addr, fsckwsp_addr;
+	s64 byte_addr_diff0, byte_addr_diff1;
+	s32 bsize;
+
+	if ((rc = readSuper(sb, &bh)))
+		return rc;
+	j_sb = (struct jfs_superblock *)bh->b_data;
+
+	/*
+	 * validate superblock
+	 */
+	/* validate fs signature */
+	if (strncmp(j_sb->s_magic, JFS_MAGIC, 4) ||
+	    le32_to_cpu(j_sb->s_version) > JFS_VERSION) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	bsize = le32_to_cpu(j_sb->s_bsize);
+	if (bsize != PSIZE) {
+		jfs_err("Only 4K block size supported!");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	jfs_info("superblock: flag:0x%08x state:0x%08x size:0x%Lx",
+		 le32_to_cpu(j_sb->s_flag), le32_to_cpu(j_sb->s_state),
+		 (unsigned long long) le64_to_cpu(j_sb->s_size));
+
+	/* validate the descriptors for Secondary AIM and AIT */
+	if ((j_sb->s_flag & cpu_to_le32(JFS_BAD_SAIT)) !=
+	    cpu_to_le32(JFS_BAD_SAIT)) {
+		expected_AIM_bytesize = 2 * PSIZE;
+		AIM_bytesize = lengthPXD(&(j_sb->s_aim2)) * bsize;
+		expected_AIT_bytesize = 4 * PSIZE;
+		AIT_bytesize = lengthPXD(&(j_sb->s_ait2)) * bsize;
+		AIM_byte_addr = addressPXD(&(j_sb->s_aim2)) * bsize;
+		AIT_byte_addr = addressPXD(&(j_sb->s_ait2)) * bsize;
+		byte_addr_diff0 = AIT_byte_addr - AIM_byte_addr;
+		fsckwsp_addr = addressPXD(&(j_sb->s_fsckpxd)) * bsize;
+		byte_addr_diff1 = fsckwsp_addr - AIT_byte_addr;
+		if ((AIM_bytesize != expected_AIM_bytesize) ||
+		    (AIT_bytesize != expected_AIT_bytesize) ||
+		    (byte_addr_diff0 != AIM_bytesize) ||
+		    (byte_addr_diff1 <= AIT_bytesize))
+			j_sb->s_flag |= cpu_to_le32(JFS_BAD_SAIT);
+	}
+
+	if ((j_sb->s_flag & cpu_to_le32(JFS_GROUPCOMMIT)) !=
+	    cpu_to_le32(JFS_GROUPCOMMIT))
+		j_sb->s_flag |= cpu_to_le32(JFS_GROUPCOMMIT);
+
+	/* validate fs state */
+	if (j_sb->s_state != cpu_to_le32(FM_CLEAN) &&
+	    !sb_rdonly(sb)) {
+		jfs_err("jfs_mount: Mount Failure: File System Dirty.");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	sbi->state = le32_to_cpu(j_sb->s_state);
+	sbi->mntflag = le32_to_cpu(j_sb->s_flag);
+
+	/*
+	 * JFS always does I/O by 4K pages.  Don't tell the buffer cache
+	 * that we use anything else (leave s_blocksize alone).
+	 */
+	sbi->bsize = bsize;
+	sbi->l2bsize = le16_to_cpu(j_sb->s_l2bsize);
+
+	/* check some fields for possible corruption */
+	if (sbi->l2bsize != ilog2((u32)bsize) ||
+	    j_sb->pad != 0 ||
+	    le32_to_cpu(j_sb->s_state) > FM_STATE_MAX) {
+		rc = -EINVAL;
+		jfs_err("jfs_mount: Mount Failure: superblock is corrupt!");
+		goto out;
+	}
+
+	/*
+	 * For now, ignore s_pbsize, l2bfactor.  All I/O going through buffer
+	 * cache.
+	 */
+	sbi->nbperpage = PSIZE >> sbi->l2bsize;
+	sbi->l2nbperpage = L2PSIZE - sbi->l2bsize;
+	sbi->l2niperblk = sbi->l2bsize - L2DISIZE;
+	if (sbi->mntflag & JFS_INLINELOG)
+		sbi->logpxd = j_sb->s_logpxd;
+	else {
+		sbi->logdev = new_decode_dev(le32_to_cpu(j_sb->s_logdev));
+		uuid_copy(&sbi->uuid, &j_sb->s_uuid);
+		uuid_copy(&sbi->loguuid, &j_sb->s_loguuid);
+	}
+	sbi->fsckpxd = j_sb->s_fsckpxd;
+	sbi->ait2 = j_sb->s_ait2;
+
+      out:
+	brelse(bh);
+	return rc;
+}
+
+
+/*
+ *	updateSuper()
+ *
+ * update synchronously superblock if it is mounted read-write.
+ */
+int updateSuper(struct super_block *sb, uint state)
+{
+	struct jfs_superblock *j_sb;
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct buffer_head *bh;
+	int rc;
+
+	if (sbi->flag & JFS_NOINTEGRITY) {
+		if (state == FM_DIRTY) {
+			sbi->p_state = state;
+			return 0;
+		} else if (state == FM_MOUNT) {
+			sbi->p_state = sbi->state;
+			state = FM_DIRTY;
+		} else if (state == FM_CLEAN) {
+			state = sbi->p_state;
+		} else
+			jfs_err("updateSuper: bad state");
+	} else if (sbi->state == FM_DIRTY)
+		return 0;
+
+	if ((rc = readSuper(sb, &bh)))
+		return rc;
+
+	j_sb = (struct jfs_superblock *)bh->b_data;
+
+	j_sb->s_state = cpu_to_le32(state);
+	sbi->state = state;
+
+	if (state == FM_MOUNT) {
+		/* record log's dev_t and mount serial number */
+		j_sb->s_logdev = cpu_to_le32(new_encode_dev(sbi->log->bdev->bd_dev));
+		j_sb->s_logserial = cpu_to_le32(sbi->log->serial);
+	} else if (state == FM_CLEAN) {
+		/*
+		 * If this volume is shared with OS/2, OS/2 will need to
+		 * recalculate DASD usage, since we don't deal with it.
+		 */
+		if (j_sb->s_flag & cpu_to_le32(JFS_DASD_ENABLED))
+			j_sb->s_flag |= cpu_to_le32(JFS_DASD_PRIME);
+	}
+
+	mark_buffer_dirty(bh);
+	sync_dirty_buffer(bh);
+	brelse(bh);
+
+	return 0;
+}
+
+
+/*
+ *	readSuper()
+ *
+ * read superblock by raw sector address
+ */
+int readSuper(struct super_block *sb, struct buffer_head **bpp)
+{
+	/* read in primary superblock */
+	*bpp = sb_bread(sb, SUPER1_OFF >> sb->s_blocksize_bits);
+	if (*bpp)
+		return 0;
+
+	/* read in secondary/replicated superblock */
+	*bpp = sb_bread(sb, SUPER2_OFF >> sb->s_blocksize_bits);
+	if (*bpp)
+		return 0;
+
+	return -EIO;
+}
+
+
+/*
+ *	logMOUNT()
+ *
+ * function: write a MOUNT log record for file system.
+ *
+ * MOUNT record keeps logredo() from processing log records
+ * for this file system past this point in log.
+ * it is harmless if mount fails.
+ *
+ * note: MOUNT record is at aggregate level, not at fileset level,
+ * since log records of previous mounts of a fileset
+ * (e.g., AFTER record of extent allocation) have to be processed
+ * to update block allocation map at aggregate level.
+ */
+static int logMOUNT(struct super_block *sb)
+{
+	struct jfs_log *log = JFS_SBI(sb)->log;
+	struct lrd lrd;
+
+	lrd.logtid = 0;
+	lrd.backchain = 0;
+	lrd.type = cpu_to_le16(LOG_MOUNT);
+	lrd.length = 0;
+	lrd.aggregate = cpu_to_le32(new_encode_dev(sb->s_bdev->bd_dev));
+	lmLog(log, NULL, &lrd, NULL);
+
+	return 0;
+}
diff --git a/fs/jfs/jfs_superblock.h b/fs/jfs/jfs_superblock.h
new file mode 100644
index 000000000..93402c420
--- /dev/null
+++ b/fs/jfs/jfs_superblock.h
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2003
+ */
+#ifndef	_H_JFS_SUPERBLOCK
+#define _H_JFS_SUPERBLOCK
+
+#include <linux/uuid.h>
+
+/*
+ * make the magic number something a human could read
+ */
+#define JFS_MAGIC	"JFS1"	/* Magic word */
+
+#define JFS_VERSION	2	/* Version number: Version 2 */
+
+#define LV_NAME_SIZE	11	/* MUST BE 11 for OS/2 boot sector */
+
+/*
+ *	aggregate superblock
+ *
+ * The name superblock is too close to super_block, so the name has been
+ * changed to jfs_superblock.  The utilities are still using the old name.
+ */
+struct jfs_superblock {
+	char s_magic[4];	/* 4: magic number */
+	__le32 s_version;	/* 4: version number */
+
+	__le64 s_size;		/* 8: aggregate size in hardware/LVM blocks;
+				 * VFS: number of blocks
+				 */
+	__le32 s_bsize;		/* 4: aggregate block size in bytes;
+				 * VFS: fragment size
+				 */
+	__le16 s_l2bsize;	/* 2: log2 of s_bsize */
+	__le16 s_l2bfactor;	/* 2: log2(s_bsize/hardware block size) */
+	__le32 s_pbsize;	/* 4: hardware/LVM block size in bytes */
+	__le16 s_l2pbsize;	/* 2: log2 of s_pbsize */
+	__le16 pad;		/* 2: padding necessary for alignment */
+
+	__le32 s_agsize;	/* 4: allocation group size in aggr. blocks */
+
+	__le32 s_flag;		/* 4: aggregate attributes:
+				 *    see jfs_filsys.h
+				 */
+	__le32 s_state;		/* 4: mount/unmount/recovery state:
+				 *    see jfs_filsys.h
+				 */
+	__le32 s_compress;		/* 4: > 0 if data compression */
+
+	pxd_t s_ait2;		/* 8: first extent of secondary
+				 *    aggregate inode table
+				 */
+
+	pxd_t s_aim2;		/* 8: first extent of secondary
+				 *    aggregate inode map
+				 */
+	__le32 s_logdev;		/* 4: device address of log */
+	__le32 s_logserial;	/* 4: log serial number at aggregate mount */
+	pxd_t s_logpxd;		/* 8: inline log extent */
+
+	pxd_t s_fsckpxd;	/* 8: inline fsck work space extent */
+
+	struct timestruc_t s_time;	/* 8: time last updated */
+
+	__le32 s_fsckloglen;	/* 4: Number of filesystem blocks reserved for
+				 *    the fsck service log.
+				 *    N.B. These blocks are divided among the
+				 *         versions kept.  This is not a per
+				 *         version size.
+				 *    N.B. These blocks are included in the
+				 *         length field of s_fsckpxd.
+				 */
+	s8 s_fscklog;		/* 1: which fsck service log is most recent
+				 *    0 => no service log data yet
+				 *    1 => the first one
+				 *    2 => the 2nd one
+				 */
+	char s_fpack[11];	/* 11: file system volume name
+				 *     N.B. This must be 11 bytes to
+				 *          conform with the OS/2 BootSector
+				 *          requirements
+				 *          Only used when s_version is 1
+				 */
+
+	/* extendfs() parameter under s_state & FM_EXTENDFS */
+	__le64 s_xsize;		/* 8: extendfs s_size */
+	pxd_t s_xfsckpxd;	/* 8: extendfs fsckpxd */
+	pxd_t s_xlogpxd;	/* 8: extendfs logpxd */
+	uuid_t s_uuid;		/* 16: 128-bit uuid for volume */
+	char s_label[16];	/* 16: volume label */
+	uuid_t s_loguuid;	/* 16: 128-bit uuid for log device */
+
+};
+
+extern int readSuper(struct super_block *, struct buffer_head **);
+extern int updateSuper(struct super_block *, uint);
+__printf(2, 3)
+extern void jfs_error(struct super_block *, const char *, ...);
+extern int jfs_mount(struct super_block *);
+extern int jfs_mount_rw(struct super_block *, int);
+extern int jfs_umount(struct super_block *);
+extern int jfs_umount_rw(struct super_block *);
+extern int jfs_extendfs(struct super_block *, s64, int);
+
+extern struct task_struct *jfsIOthread;
+extern struct task_struct *jfsSyncThread;
+
+#endif /*_H_JFS_SUPERBLOCK */
diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
new file mode 100644
index 000000000..ce4b4760f
--- /dev/null
+++ b/fs/jfs/jfs_txnmgr.c
@@ -0,0 +1,3017 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2005
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+/*
+ *	jfs_txnmgr.c: transaction manager
+ *
+ * notes:
+ * transaction starts with txBegin() and ends with txCommit()
+ * or txAbort().
+ *
+ * tlock is acquired at the time of update;
+ * (obviate scan at commit time for xtree and dtree)
+ * tlock and mp points to each other;
+ * (no hashlist for mp -> tlock).
+ *
+ * special cases:
+ * tlock on in-memory inode:
+ * in-place tlock in the in-memory inode itself;
+ * converted to page lock by iWrite() at commit time.
+ *
+ * tlock during write()/mmap() under anonymous transaction (tid = 0):
+ * transferred (?) to transaction at commit time.
+ *
+ * use the page itself to update allocation maps
+ * (obviate intermediate replication of allocation/deallocation data)
+ * hold on to mp+lock thru update of maps
+ */
+
+#include <linux/fs.h>
+#include <linux/vmalloc.h>
+#include <linux/completion.h>
+#include <linux/freezer.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kthread.h>
+#include <linux/seq_file.h>
+#include "jfs_incore.h"
+#include "jfs_inode.h"
+#include "jfs_filsys.h"
+#include "jfs_metapage.h"
+#include "jfs_dinode.h"
+#include "jfs_imap.h"
+#include "jfs_dmap.h"
+#include "jfs_superblock.h"
+#include "jfs_debug.h"
+
+/*
+ *	transaction management structures
+ */
+static struct {
+	int freetid;		/* index of a free tid structure */
+	int freelock;		/* index first free lock word */
+	wait_queue_head_t freewait;	/* eventlist of free tblock */
+	wait_queue_head_t freelockwait;	/* eventlist of free tlock */
+	wait_queue_head_t lowlockwait;	/* eventlist of ample tlocks */
+	int tlocksInUse;	/* Number of tlocks in use */
+	spinlock_t LazyLock;	/* synchronize sync_queue & unlock_queue */
+/*	struct tblock *sync_queue; * Transactions waiting for data sync */
+	struct list_head unlock_queue;	/* Txns waiting to be released */
+	struct list_head anon_list;	/* inodes having anonymous txns */
+	struct list_head anon_list2;	/* inodes having anonymous txns
+					   that couldn't be sync'ed */
+} TxAnchor;
+
+int jfs_tlocks_low;		/* Indicates low number of available tlocks */
+
+#ifdef CONFIG_JFS_STATISTICS
+static struct {
+	uint txBegin;
+	uint txBegin_barrier;
+	uint txBegin_lockslow;
+	uint txBegin_freetid;
+	uint txBeginAnon;
+	uint txBeginAnon_barrier;
+	uint txBeginAnon_lockslow;
+	uint txLockAlloc;
+	uint txLockAlloc_freelock;
+} TxStat;
+#endif
+
+static int nTxBlock = -1;	/* number of transaction blocks */
+module_param(nTxBlock, int, 0);
+MODULE_PARM_DESC(nTxBlock,
+		 "Number of transaction blocks (max:65536)");
+
+static int nTxLock = -1;	/* number of transaction locks */
+module_param(nTxLock, int, 0);
+MODULE_PARM_DESC(nTxLock,
+		 "Number of transaction locks (max:65536)");
+
+struct tblock *TxBlock;	/* transaction block table */
+static int TxLockLWM;	/* Low water mark for number of txLocks used */
+static int TxLockHWM;	/* High water mark for number of txLocks used */
+static int TxLockVHWM;	/* Very High water mark */
+struct tlock *TxLock;	/* transaction lock table */
+
+/*
+ *	transaction management lock
+ */
+static DEFINE_SPINLOCK(jfsTxnLock);
+
+#define TXN_LOCK()		spin_lock(&jfsTxnLock)
+#define TXN_UNLOCK()		spin_unlock(&jfsTxnLock)
+
+#define LAZY_LOCK_INIT()	spin_lock_init(&TxAnchor.LazyLock)
+#define LAZY_LOCK(flags)	spin_lock_irqsave(&TxAnchor.LazyLock, flags)
+#define LAZY_UNLOCK(flags) spin_unlock_irqrestore(&TxAnchor.LazyLock, flags)
+
+static DECLARE_WAIT_QUEUE_HEAD(jfs_commit_thread_wait);
+static int jfs_commit_thread_waking;
+
+/*
+ * Retry logic exist outside these macros to protect from spurrious wakeups.
+ */
+static inline void TXN_SLEEP_DROP_LOCK(wait_queue_head_t * event)
+{
+	DECLARE_WAITQUEUE(wait, current);
+
+	add_wait_queue(event, &wait);
+	set_current_state(TASK_UNINTERRUPTIBLE);
+	TXN_UNLOCK();
+	io_schedule();
+	remove_wait_queue(event, &wait);
+}
+
+#define TXN_SLEEP(event)\
+{\
+	TXN_SLEEP_DROP_LOCK(event);\
+	TXN_LOCK();\
+}
+
+#define TXN_WAKEUP(event) wake_up_all(event)
+
+/*
+ *	statistics
+ */
+static struct {
+	tid_t maxtid;		/* 4: biggest tid ever used */
+	lid_t maxlid;		/* 4: biggest lid ever used */
+	int ntid;		/* 4: # of transactions performed */
+	int nlid;		/* 4: # of tlocks acquired */
+	int waitlock;		/* 4: # of tlock wait */
+} stattx;
+
+/*
+ * forward references
+ */
+static void diLog(struct jfs_log *log, struct tblock *tblk, struct lrd *lrd,
+		struct tlock *tlck, struct commit *cd);
+static void dataLog(struct jfs_log *log, struct tblock *tblk, struct lrd *lrd,
+		struct tlock *tlck);
+static void dtLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
+		struct tlock * tlck);
+static void mapLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
+		struct tlock * tlck);
+static void txAllocPMap(struct inode *ip, struct maplock * maplock,
+		struct tblock * tblk);
+static void txForce(struct tblock * tblk);
+static void txLog(struct jfs_log *log, struct tblock *tblk,
+		struct commit *cd);
+static void txUpdateMap(struct tblock * tblk);
+static void txRelease(struct tblock * tblk);
+static void xtLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
+	   struct tlock * tlck);
+static void LogSyncRelease(struct metapage * mp);
+
+/*
+ *		transaction block/lock management
+ *		---------------------------------
+ */
+
+/*
+ * Get a transaction lock from the free list.  If the number in use is
+ * greater than the high water mark, wake up the sync daemon.  This should
+ * free some anonymous transaction locks.  (TXN_LOCK must be held.)
+ */
+static lid_t txLockAlloc(void)
+{
+	lid_t lid;
+
+	INCREMENT(TxStat.txLockAlloc);
+	if (!TxAnchor.freelock) {
+		INCREMENT(TxStat.txLockAlloc_freelock);
+	}
+
+	while (!(lid = TxAnchor.freelock))
+		TXN_SLEEP(&TxAnchor.freelockwait);
+	TxAnchor.freelock = TxLock[lid].next;
+	HIGHWATERMARK(stattx.maxlid, lid);
+	if ((++TxAnchor.tlocksInUse > TxLockHWM) && (jfs_tlocks_low == 0)) {
+		jfs_info("txLockAlloc tlocks low");
+		jfs_tlocks_low = 1;
+		wake_up_process(jfsSyncThread);
+	}
+
+	return lid;
+}
+
+static void txLockFree(lid_t lid)
+{
+	TxLock[lid].tid = 0;
+	TxLock[lid].next = TxAnchor.freelock;
+	TxAnchor.freelock = lid;
+	TxAnchor.tlocksInUse--;
+	if (jfs_tlocks_low && (TxAnchor.tlocksInUse < TxLockLWM)) {
+		jfs_info("txLockFree jfs_tlocks_low no more");
+		jfs_tlocks_low = 0;
+		TXN_WAKEUP(&TxAnchor.lowlockwait);
+	}
+	TXN_WAKEUP(&TxAnchor.freelockwait);
+}
+
+/*
+ * NAME:	txInit()
+ *
+ * FUNCTION:	initialize transaction management structures
+ *
+ * RETURN:
+ *
+ * serialization: single thread at jfs_init()
+ */
+int txInit(void)
+{
+	int k, size;
+	struct sysinfo si;
+
+	/* Set defaults for nTxLock and nTxBlock if unset */
+
+	if (nTxLock == -1) {
+		if (nTxBlock == -1) {
+			/* Base default on memory size */
+			si_meminfo(&si);
+			if (si.totalram > (256 * 1024)) /* 1 GB */
+				nTxLock = 64 * 1024;
+			else
+				nTxLock = si.totalram >> 2;
+		} else if (nTxBlock > (8 * 1024))
+			nTxLock = 64 * 1024;
+		else
+			nTxLock = nTxBlock << 3;
+	}
+	if (nTxBlock == -1)
+		nTxBlock = nTxLock >> 3;
+
+	/* Verify tunable parameters */
+	if (nTxBlock < 16)
+		nTxBlock = 16;	/* No one should set it this low */
+	if (nTxBlock > 65536)
+		nTxBlock = 65536;
+	if (nTxLock < 256)
+		nTxLock = 256;	/* No one should set it this low */
+	if (nTxLock > 65536)
+		nTxLock = 65536;
+
+	printk(KERN_INFO "JFS: nTxBlock = %d, nTxLock = %d\n",
+	       nTxBlock, nTxLock);
+	/*
+	 * initialize transaction block (tblock) table
+	 *
+	 * transaction id (tid) = tblock index
+	 * tid = 0 is reserved.
+	 */
+	TxLockLWM = (nTxLock * 4) / 10;
+	TxLockHWM = (nTxLock * 7) / 10;
+	TxLockVHWM = (nTxLock * 8) / 10;
+
+	size = sizeof(struct tblock) * nTxBlock;
+	TxBlock = vmalloc(size);
+	if (TxBlock == NULL)
+		return -ENOMEM;
+
+	for (k = 1; k < nTxBlock - 1; k++) {
+		TxBlock[k].next = k + 1;
+		init_waitqueue_head(&TxBlock[k].gcwait);
+		init_waitqueue_head(&TxBlock[k].waitor);
+	}
+	TxBlock[k].next = 0;
+	init_waitqueue_head(&TxBlock[k].gcwait);
+	init_waitqueue_head(&TxBlock[k].waitor);
+
+	TxAnchor.freetid = 1;
+	init_waitqueue_head(&TxAnchor.freewait);
+
+	stattx.maxtid = 1;	/* statistics */
+
+	/*
+	 * initialize transaction lock (tlock) table
+	 *
+	 * transaction lock id = tlock index
+	 * tlock id = 0 is reserved.
+	 */
+	size = sizeof(struct tlock) * nTxLock;
+	TxLock = vmalloc(size);
+	if (TxLock == NULL) {
+		vfree(TxBlock);
+		return -ENOMEM;
+	}
+
+	/* initialize tlock table */
+	for (k = 1; k < nTxLock - 1; k++)
+		TxLock[k].next = k + 1;
+	TxLock[k].next = 0;
+	init_waitqueue_head(&TxAnchor.freelockwait);
+	init_waitqueue_head(&TxAnchor.lowlockwait);
+
+	TxAnchor.freelock = 1;
+	TxAnchor.tlocksInUse = 0;
+	INIT_LIST_HEAD(&TxAnchor.anon_list);
+	INIT_LIST_HEAD(&TxAnchor.anon_list2);
+
+	LAZY_LOCK_INIT();
+	INIT_LIST_HEAD(&TxAnchor.unlock_queue);
+
+	stattx.maxlid = 1;	/* statistics */
+
+	return 0;
+}
+
+/*
+ * NAME:	txExit()
+ *
+ * FUNCTION:	clean up when module is unloaded
+ */
+void txExit(void)
+{
+	vfree(TxLock);
+	TxLock = NULL;
+	vfree(TxBlock);
+	TxBlock = NULL;
+}
+
+/*
+ * NAME:	txBegin()
+ *
+ * FUNCTION:	start a transaction.
+ *
+ * PARAMETER:	sb	- superblock
+ *		flag	- force for nested tx;
+ *
+ * RETURN:	tid	- transaction id
+ *
+ * note: flag force allows to start tx for nested tx
+ * to prevent deadlock on logsync barrier;
+ */
+tid_t txBegin(struct super_block *sb, int flag)
+{
+	tid_t t;
+	struct tblock *tblk;
+	struct jfs_log *log;
+
+	jfs_info("txBegin: flag = 0x%x", flag);
+	log = JFS_SBI(sb)->log;
+
+	if (!log) {
+		jfs_error(sb, "read-only filesystem\n");
+		return 0;
+	}
+
+	TXN_LOCK();
+
+	INCREMENT(TxStat.txBegin);
+
+      retry:
+	if (!(flag & COMMIT_FORCE)) {
+		/*
+		 * synchronize with logsync barrier
+		 */
+		if (test_bit(log_SYNCBARRIER, &log->flag) ||
+		    test_bit(log_QUIESCE, &log->flag)) {
+			INCREMENT(TxStat.txBegin_barrier);
+			TXN_SLEEP(&log->syncwait);
+			goto retry;
+		}
+	}
+	if (flag == 0) {
+		/*
+		 * Don't begin transaction if we're getting starved for tlocks
+		 * unless COMMIT_FORCE or COMMIT_INODE (which may ultimately
+		 * free tlocks)
+		 */
+		if (TxAnchor.tlocksInUse > TxLockVHWM) {
+			INCREMENT(TxStat.txBegin_lockslow);
+			TXN_SLEEP(&TxAnchor.lowlockwait);
+			goto retry;
+		}
+	}
+
+	/*
+	 * allocate transaction id/block
+	 */
+	if ((t = TxAnchor.freetid) == 0) {
+		jfs_info("txBegin: waiting for free tid");
+		INCREMENT(TxStat.txBegin_freetid);
+		TXN_SLEEP(&TxAnchor.freewait);
+		goto retry;
+	}
+
+	tblk = tid_to_tblock(t);
+
+	if ((tblk->next == 0) && !(flag & COMMIT_FORCE)) {
+		/* Don't let a non-forced transaction take the last tblk */
+		jfs_info("txBegin: waiting for free tid");
+		INCREMENT(TxStat.txBegin_freetid);
+		TXN_SLEEP(&TxAnchor.freewait);
+		goto retry;
+	}
+
+	TxAnchor.freetid = tblk->next;
+
+	/*
+	 * initialize transaction
+	 */
+
+	/*
+	 * We can't zero the whole thing or we screw up another thread being
+	 * awakened after sleeping on tblk->waitor
+	 *
+	 * memset(tblk, 0, sizeof(struct tblock));
+	 */
+	tblk->next = tblk->last = tblk->xflag = tblk->flag = tblk->lsn = 0;
+
+	tblk->sb = sb;
+	++log->logtid;
+	tblk->logtid = log->logtid;
+
+	++log->active;
+
+	HIGHWATERMARK(stattx.maxtid, t);	/* statistics */
+	INCREMENT(stattx.ntid);	/* statistics */
+
+	TXN_UNLOCK();
+
+	jfs_info("txBegin: returning tid = %d", t);
+
+	return t;
+}
+
+/*
+ * NAME:	txBeginAnon()
+ *
+ * FUNCTION:	start an anonymous transaction.
+ *		Blocks if logsync or available tlocks are low to prevent
+ *		anonymous tlocks from depleting supply.
+ *
+ * PARAMETER:	sb	- superblock
+ *
+ * RETURN:	none
+ */
+void txBeginAnon(struct super_block *sb)
+{
+	struct jfs_log *log;
+
+	log = JFS_SBI(sb)->log;
+
+	TXN_LOCK();
+	INCREMENT(TxStat.txBeginAnon);
+
+      retry:
+	/*
+	 * synchronize with logsync barrier
+	 */
+	if (test_bit(log_SYNCBARRIER, &log->flag) ||
+	    test_bit(log_QUIESCE, &log->flag)) {
+		INCREMENT(TxStat.txBeginAnon_barrier);
+		TXN_SLEEP(&log->syncwait);
+		goto retry;
+	}
+
+	/*
+	 * Don't begin transaction if we're getting starved for tlocks
+	 */
+	if (TxAnchor.tlocksInUse > TxLockVHWM) {
+		INCREMENT(TxStat.txBeginAnon_lockslow);
+		TXN_SLEEP(&TxAnchor.lowlockwait);
+		goto retry;
+	}
+	TXN_UNLOCK();
+}
+
+/*
+ *	txEnd()
+ *
+ * function: free specified transaction block.
+ *
+ *	logsync barrier processing:
+ *
+ * serialization:
+ */
+void txEnd(tid_t tid)
+{
+	struct tblock *tblk = tid_to_tblock(tid);
+	struct jfs_log *log;
+
+	jfs_info("txEnd: tid = %d", tid);
+	TXN_LOCK();
+
+	/*
+	 * wakeup transactions waiting on the page locked
+	 * by the current transaction
+	 */
+	TXN_WAKEUP(&tblk->waitor);
+
+	log = JFS_SBI(tblk->sb)->log;
+
+	/*
+	 * Lazy commit thread can't free this guy until we mark it UNLOCKED,
+	 * otherwise, we would be left with a transaction that may have been
+	 * reused.
+	 *
+	 * Lazy commit thread will turn off tblkGC_LAZY before calling this
+	 * routine.
+	 */
+	if (tblk->flag & tblkGC_LAZY) {
+		jfs_info("txEnd called w/lazy tid: %d, tblk = 0x%p", tid, tblk);
+		TXN_UNLOCK();
+
+		spin_lock_irq(&log->gclock);	// LOGGC_LOCK
+		tblk->flag |= tblkGC_UNLOCKED;
+		spin_unlock_irq(&log->gclock);	// LOGGC_UNLOCK
+		return;
+	}
+
+	jfs_info("txEnd: tid: %d, tblk = 0x%p", tid, tblk);
+
+	assert(tblk->next == 0);
+
+	/*
+	 * insert tblock back on freelist
+	 */
+	tblk->next = TxAnchor.freetid;
+	TxAnchor.freetid = tid;
+
+	/*
+	 * mark the tblock not active
+	 */
+	if (--log->active == 0) {
+		clear_bit(log_FLUSH, &log->flag);
+
+		/*
+		 * synchronize with logsync barrier
+		 */
+		if (test_bit(log_SYNCBARRIER, &log->flag)) {
+			TXN_UNLOCK();
+
+			/* write dirty metadata & forward log syncpt */
+			jfs_syncpt(log, 1);
+
+			jfs_info("log barrier off: 0x%x", log->lsn);
+
+			/* enable new transactions start */
+			clear_bit(log_SYNCBARRIER, &log->flag);
+
+			/* wakeup all waitors for logsync barrier */
+			TXN_WAKEUP(&log->syncwait);
+
+			goto wakeup;
+		}
+	}
+
+	TXN_UNLOCK();
+wakeup:
+	/*
+	 * wakeup all waitors for a free tblock
+	 */
+	TXN_WAKEUP(&TxAnchor.freewait);
+}
+
+/*
+ *	txLock()
+ *
+ * function: acquire a transaction lock on the specified <mp>
+ *
+ * parameter:
+ *
+ * return:	transaction lock id
+ *
+ * serialization:
+ */
+struct tlock *txLock(tid_t tid, struct inode *ip, struct metapage * mp,
+		     int type)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	int dir_xtree = 0;
+	lid_t lid;
+	tid_t xtid;
+	struct tlock *tlck;
+	struct xtlock *xtlck;
+	struct linelock *linelock;
+	xtpage_t *p;
+	struct tblock *tblk;
+
+	TXN_LOCK();
+
+	if (S_ISDIR(ip->i_mode) && (type & tlckXTREE) &&
+	    !(mp->xflag & COMMIT_PAGE)) {
+		/*
+		 * Directory inode is special.  It can have both an xtree tlock
+		 * and a dtree tlock associated with it.
+		 */
+		dir_xtree = 1;
+		lid = jfs_ip->xtlid;
+	} else
+		lid = mp->lid;
+
+	/* is page not locked by a transaction ? */
+	if (lid == 0)
+		goto allocateLock;
+
+	jfs_info("txLock: tid:%d ip:0x%p mp:0x%p lid:%d", tid, ip, mp, lid);
+
+	/* is page locked by the requester transaction ? */
+	tlck = lid_to_tlock(lid);
+	if ((xtid = tlck->tid) == tid) {
+		TXN_UNLOCK();
+		goto grantLock;
+	}
+
+	/*
+	 * is page locked by anonymous transaction/lock ?
+	 *
+	 * (page update without transaction (i.e., file write) is
+	 * locked under anonymous transaction tid = 0:
+	 * anonymous tlocks maintained on anonymous tlock list of
+	 * the inode of the page and available to all anonymous
+	 * transactions until txCommit() time at which point
+	 * they are transferred to the transaction tlock list of
+	 * the committing transaction of the inode)
+	 */
+	if (xtid == 0) {
+		tlck->tid = tid;
+		TXN_UNLOCK();
+		tblk = tid_to_tblock(tid);
+		/*
+		 * The order of the tlocks in the transaction is important
+		 * (during truncate, child xtree pages must be freed before
+		 * parent's tlocks change the working map).
+		 * Take tlock off anonymous list and add to tail of
+		 * transaction list
+		 *
+		 * Note:  We really need to get rid of the tid & lid and
+		 * use list_head's.  This code is getting UGLY!
+		 */
+		if (jfs_ip->atlhead == lid) {
+			if (jfs_ip->atltail == lid) {
+				/* only anonymous txn.
+				 * Remove from anon_list
+				 */
+				TXN_LOCK();
+				list_del_init(&jfs_ip->anon_inode_list);
+				TXN_UNLOCK();
+			}
+			jfs_ip->atlhead = tlck->next;
+		} else {
+			lid_t last;
+			for (last = jfs_ip->atlhead;
+			     lid_to_tlock(last)->next != lid;
+			     last = lid_to_tlock(last)->next) {
+				assert(last);
+			}
+			lid_to_tlock(last)->next = tlck->next;
+			if (jfs_ip->atltail == lid)
+				jfs_ip->atltail = last;
+		}
+
+		/* insert the tlock at tail of transaction tlock list */
+
+		if (tblk->next)
+			lid_to_tlock(tblk->last)->next = lid;
+		else
+			tblk->next = lid;
+		tlck->next = 0;
+		tblk->last = lid;
+
+		goto grantLock;
+	}
+
+	goto waitLock;
+
+	/*
+	 * allocate a tlock
+	 */
+      allocateLock:
+	lid = txLockAlloc();
+	tlck = lid_to_tlock(lid);
+
+	/*
+	 * initialize tlock
+	 */
+	tlck->tid = tid;
+
+	TXN_UNLOCK();
+
+	/* mark tlock for meta-data page */
+	if (mp->xflag & COMMIT_PAGE) {
+
+		tlck->flag = tlckPAGELOCK;
+
+		/* mark the page dirty and nohomeok */
+		metapage_nohomeok(mp);
+
+		jfs_info("locking mp = 0x%p, nohomeok = %d tid = %d tlck = 0x%p",
+			 mp, mp->nohomeok, tid, tlck);
+
+		/* if anonymous transaction, and buffer is on the group
+		 * commit synclist, mark inode to show this.  This will
+		 * prevent the buffer from being marked nohomeok for too
+		 * long a time.
+		 */
+		if ((tid == 0) && mp->lsn)
+			set_cflag(COMMIT_Synclist, ip);
+	}
+	/* mark tlock for in-memory inode */
+	else
+		tlck->flag = tlckINODELOCK;
+
+	if (S_ISDIR(ip->i_mode))
+		tlck->flag |= tlckDIRECTORY;
+
+	tlck->type = 0;
+
+	/* bind the tlock and the page */
+	tlck->ip = ip;
+	tlck->mp = mp;
+	if (dir_xtree)
+		jfs_ip->xtlid = lid;
+	else
+		mp->lid = lid;
+
+	/*
+	 * enqueue transaction lock to transaction/inode
+	 */
+	/* insert the tlock at tail of transaction tlock list */
+	if (tid) {
+		tblk = tid_to_tblock(tid);
+		if (tblk->next)
+			lid_to_tlock(tblk->last)->next = lid;
+		else
+			tblk->next = lid;
+		tlck->next = 0;
+		tblk->last = lid;
+	}
+	/* anonymous transaction:
+	 * insert the tlock at head of inode anonymous tlock list
+	 */
+	else {
+		tlck->next = jfs_ip->atlhead;
+		jfs_ip->atlhead = lid;
+		if (tlck->next == 0) {
+			/* This inode's first anonymous transaction */
+			jfs_ip->atltail = lid;
+			TXN_LOCK();
+			list_add_tail(&jfs_ip->anon_inode_list,
+				      &TxAnchor.anon_list);
+			TXN_UNLOCK();
+		}
+	}
+
+	/* initialize type dependent area for linelock */
+	linelock = (struct linelock *) & tlck->lock;
+	linelock->next = 0;
+	linelock->flag = tlckLINELOCK;
+	linelock->maxcnt = TLOCKSHORT;
+	linelock->index = 0;
+
+	switch (type & tlckTYPE) {
+	case tlckDTREE:
+		linelock->l2linesize = L2DTSLOTSIZE;
+		break;
+
+	case tlckXTREE:
+		linelock->l2linesize = L2XTSLOTSIZE;
+
+		xtlck = (struct xtlock *) linelock;
+		xtlck->header.offset = 0;
+		xtlck->header.length = 2;
+
+		if (type & tlckNEW) {
+			xtlck->lwm.offset = XTENTRYSTART;
+		} else {
+			if (mp->xflag & COMMIT_PAGE)
+				p = (xtpage_t *) mp->data;
+			else
+				p = &jfs_ip->i_xtroot;
+			xtlck->lwm.offset =
+			    le16_to_cpu(p->header.nextindex);
+		}
+		xtlck->lwm.length = 0;	/* ! */
+		xtlck->twm.offset = 0;
+		xtlck->hwm.offset = 0;
+
+		xtlck->index = 2;
+		break;
+
+	case tlckINODE:
+		linelock->l2linesize = L2INODESLOTSIZE;
+		break;
+
+	case tlckDATA:
+		linelock->l2linesize = L2DATASLOTSIZE;
+		break;
+
+	default:
+		jfs_err("UFO tlock:0x%p", tlck);
+	}
+
+	/*
+	 * update tlock vector
+	 */
+      grantLock:
+	tlck->type |= type;
+
+	return tlck;
+
+	/*
+	 * page is being locked by another transaction:
+	 */
+      waitLock:
+	/* Only locks on ipimap or ipaimap should reach here */
+	/* assert(jfs_ip->fileset == AGGREGATE_I); */
+	if (jfs_ip->fileset != AGGREGATE_I) {
+		printk(KERN_ERR "txLock: trying to lock locked page!");
+		print_hex_dump(KERN_ERR, "ip: ", DUMP_PREFIX_ADDRESS, 16, 4,
+			       ip, sizeof(*ip), 0);
+		print_hex_dump(KERN_ERR, "mp: ", DUMP_PREFIX_ADDRESS, 16, 4,
+			       mp, sizeof(*mp), 0);
+		print_hex_dump(KERN_ERR, "Locker's tblock: ",
+			       DUMP_PREFIX_ADDRESS, 16, 4, tid_to_tblock(tid),
+			       sizeof(struct tblock), 0);
+		print_hex_dump(KERN_ERR, "Tlock: ", DUMP_PREFIX_ADDRESS, 16, 4,
+			       tlck, sizeof(*tlck), 0);
+		BUG();
+	}
+	INCREMENT(stattx.waitlock);	/* statistics */
+	TXN_UNLOCK();
+	release_metapage(mp);
+	TXN_LOCK();
+	xtid = tlck->tid;	/* reacquire after dropping TXN_LOCK */
+
+	jfs_info("txLock: in waitLock, tid = %d, xtid = %d, lid = %d",
+		 tid, xtid, lid);
+
+	/* Recheck everything since dropping TXN_LOCK */
+	if (xtid && (tlck->mp == mp) && (mp->lid == lid))
+		TXN_SLEEP_DROP_LOCK(&tid_to_tblock(xtid)->waitor);
+	else
+		TXN_UNLOCK();
+	jfs_info("txLock: awakened     tid = %d, lid = %d", tid, lid);
+
+	return NULL;
+}
+
+/*
+ * NAME:	txRelease()
+ *
+ * FUNCTION:	Release buffers associated with transaction locks, but don't
+ *		mark homeok yet.  The allows other transactions to modify
+ *		buffers, but won't let them go to disk until commit record
+ *		actually gets written.
+ *
+ * PARAMETER:
+ *		tblk	-
+ *
+ * RETURN:	Errors from subroutines.
+ */
+static void txRelease(struct tblock * tblk)
+{
+	struct metapage *mp;
+	lid_t lid;
+	struct tlock *tlck;
+
+	TXN_LOCK();
+
+	for (lid = tblk->next; lid; lid = tlck->next) {
+		tlck = lid_to_tlock(lid);
+		if ((mp = tlck->mp) != NULL &&
+		    (tlck->type & tlckBTROOT) == 0) {
+			assert(mp->xflag & COMMIT_PAGE);
+			mp->lid = 0;
+		}
+	}
+
+	/*
+	 * wakeup transactions waiting on a page locked
+	 * by the current transaction
+	 */
+	TXN_WAKEUP(&tblk->waitor);
+
+	TXN_UNLOCK();
+}
+
+/*
+ * NAME:	txUnlock()
+ *
+ * FUNCTION:	Initiates pageout of pages modified by tid in journalled
+ *		objects and frees their lockwords.
+ */
+static void txUnlock(struct tblock * tblk)
+{
+	struct tlock *tlck;
+	struct linelock *linelock;
+	lid_t lid, next, llid, k;
+	struct metapage *mp;
+	struct jfs_log *log;
+	int difft, diffp;
+	unsigned long flags;
+
+	jfs_info("txUnlock: tblk = 0x%p", tblk);
+	log = JFS_SBI(tblk->sb)->log;
+
+	/*
+	 * mark page under tlock homeok (its log has been written):
+	 */
+	for (lid = tblk->next; lid; lid = next) {
+		tlck = lid_to_tlock(lid);
+		next = tlck->next;
+
+		jfs_info("unlocking lid = %d, tlck = 0x%p", lid, tlck);
+
+		/* unbind page from tlock */
+		if ((mp = tlck->mp) != NULL &&
+		    (tlck->type & tlckBTROOT) == 0) {
+			assert(mp->xflag & COMMIT_PAGE);
+
+			/* hold buffer
+			 */
+			hold_metapage(mp);
+
+			assert(mp->nohomeok > 0);
+			_metapage_homeok(mp);
+
+			/* inherit younger/larger clsn */
+			LOGSYNC_LOCK(log, flags);
+			if (mp->clsn) {
+				logdiff(difft, tblk->clsn, log);
+				logdiff(diffp, mp->clsn, log);
+				if (difft > diffp)
+					mp->clsn = tblk->clsn;
+			} else
+				mp->clsn = tblk->clsn;
+			LOGSYNC_UNLOCK(log, flags);
+
+			assert(!(tlck->flag & tlckFREEPAGE));
+
+			put_metapage(mp);
+		}
+
+		/* insert tlock, and linelock(s) of the tlock if any,
+		 * at head of freelist
+		 */
+		TXN_LOCK();
+
+		llid = ((struct linelock *) & tlck->lock)->next;
+		while (llid) {
+			linelock = (struct linelock *) lid_to_tlock(llid);
+			k = linelock->next;
+			txLockFree(llid);
+			llid = k;
+		}
+		txLockFree(lid);
+
+		TXN_UNLOCK();
+	}
+	tblk->next = tblk->last = 0;
+
+	/*
+	 * remove tblock from logsynclist
+	 * (allocation map pages inherited lsn of tblk and
+	 * has been inserted in logsync list at txUpdateMap())
+	 */
+	if (tblk->lsn) {
+		LOGSYNC_LOCK(log, flags);
+		log->count--;
+		list_del(&tblk->synclist);
+		LOGSYNC_UNLOCK(log, flags);
+	}
+}
+
+/*
+ *	txMaplock()
+ *
+ * function: allocate a transaction lock for freed page/entry;
+ *	for freed page, maplock is used as xtlock/dtlock type;
+ */
+struct tlock *txMaplock(tid_t tid, struct inode *ip, int type)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	lid_t lid;
+	struct tblock *tblk;
+	struct tlock *tlck;
+	struct maplock *maplock;
+
+	TXN_LOCK();
+
+	/*
+	 * allocate a tlock
+	 */
+	lid = txLockAlloc();
+	tlck = lid_to_tlock(lid);
+
+	/*
+	 * initialize tlock
+	 */
+	tlck->tid = tid;
+
+	/* bind the tlock and the object */
+	tlck->flag = tlckINODELOCK;
+	if (S_ISDIR(ip->i_mode))
+		tlck->flag |= tlckDIRECTORY;
+	tlck->ip = ip;
+	tlck->mp = NULL;
+
+	tlck->type = type;
+
+	/*
+	 * enqueue transaction lock to transaction/inode
+	 */
+	/* insert the tlock at tail of transaction tlock list */
+	if (tid) {
+		tblk = tid_to_tblock(tid);
+		if (tblk->next)
+			lid_to_tlock(tblk->last)->next = lid;
+		else
+			tblk->next = lid;
+		tlck->next = 0;
+		tblk->last = lid;
+	}
+	/* anonymous transaction:
+	 * insert the tlock at head of inode anonymous tlock list
+	 */
+	else {
+		tlck->next = jfs_ip->atlhead;
+		jfs_ip->atlhead = lid;
+		if (tlck->next == 0) {
+			/* This inode's first anonymous transaction */
+			jfs_ip->atltail = lid;
+			list_add_tail(&jfs_ip->anon_inode_list,
+				      &TxAnchor.anon_list);
+		}
+	}
+
+	TXN_UNLOCK();
+
+	/* initialize type dependent area for maplock */
+	maplock = (struct maplock *) & tlck->lock;
+	maplock->next = 0;
+	maplock->maxcnt = 0;
+	maplock->index = 0;
+
+	return tlck;
+}
+
+/*
+ *	txLinelock()
+ *
+ * function: allocate a transaction lock for log vector list
+ */
+struct linelock *txLinelock(struct linelock * tlock)
+{
+	lid_t lid;
+	struct tlock *tlck;
+	struct linelock *linelock;
+
+	TXN_LOCK();
+
+	/* allocate a TxLock structure */
+	lid = txLockAlloc();
+	tlck = lid_to_tlock(lid);
+
+	TXN_UNLOCK();
+
+	/* initialize linelock */
+	linelock = (struct linelock *) tlck;
+	linelock->next = 0;
+	linelock->flag = tlckLINELOCK;
+	linelock->maxcnt = TLOCKLONG;
+	linelock->index = 0;
+	if (tlck->flag & tlckDIRECTORY)
+		linelock->flag |= tlckDIRECTORY;
+
+	/* append linelock after tlock */
+	linelock->next = tlock->next;
+	tlock->next = lid;
+
+	return linelock;
+}
+
+/*
+ *		transaction commit management
+ *		-----------------------------
+ */
+
+/*
+ * NAME:	txCommit()
+ *
+ * FUNCTION:	commit the changes to the objects specified in
+ *		clist.  For journalled segments only the
+ *		changes of the caller are committed, ie by tid.
+ *		for non-journalled segments the data are flushed to
+ *		disk and then the change to the disk inode and indirect
+ *		blocks committed (so blocks newly allocated to the
+ *		segment will be made a part of the segment atomically).
+ *
+ *		all of the segments specified in clist must be in
+ *		one file system. no more than 6 segments are needed
+ *		to handle all unix svcs.
+ *
+ *		if the i_nlink field (i.e. disk inode link count)
+ *		is zero, and the type of inode is a regular file or
+ *		directory, or symbolic link , the inode is truncated
+ *		to zero length. the truncation is committed but the
+ *		VM resources are unaffected until it is closed (see
+ *		iput and iclose).
+ *
+ * PARAMETER:
+ *
+ * RETURN:
+ *
+ * serialization:
+ *		on entry the inode lock on each segment is assumed
+ *		to be held.
+ *
+ * i/o error:
+ */
+int txCommit(tid_t tid,		/* transaction identifier */
+	     int nip,		/* number of inodes to commit */
+	     struct inode **iplist,	/* list of inode to commit */
+	     int flag)
+{
+	int rc = 0;
+	struct commit cd;
+	struct jfs_log *log;
+	struct tblock *tblk;
+	struct lrd *lrd;
+	struct inode *ip;
+	struct jfs_inode_info *jfs_ip;
+	int k, n;
+	ino_t top;
+	struct super_block *sb;
+
+	jfs_info("txCommit, tid = %d, flag = %d", tid, flag);
+	/* is read-only file system ? */
+	if (isReadOnly(iplist[0])) {
+		rc = -EROFS;
+		goto TheEnd;
+	}
+
+	sb = cd.sb = iplist[0]->i_sb;
+	cd.tid = tid;
+
+	if (tid == 0)
+		tid = txBegin(sb, 0);
+	tblk = tid_to_tblock(tid);
+
+	/*
+	 * initialize commit structure
+	 */
+	log = JFS_SBI(sb)->log;
+	cd.log = log;
+
+	/* initialize log record descriptor in commit */
+	lrd = &cd.lrd;
+	lrd->logtid = cpu_to_le32(tblk->logtid);
+	lrd->backchain = 0;
+
+	tblk->xflag |= flag;
+
+	if ((flag & (COMMIT_FORCE | COMMIT_SYNC)) == 0)
+		tblk->xflag |= COMMIT_LAZY;
+	/*
+	 *	prepare non-journaled objects for commit
+	 *
+	 * flush data pages of non-journaled file
+	 * to prevent the file getting non-initialized disk blocks
+	 * in case of crash.
+	 * (new blocks - )
+	 */
+	cd.iplist = iplist;
+	cd.nip = nip;
+
+	/*
+	 *	acquire transaction lock on (on-disk) inodes
+	 *
+	 * update on-disk inode from in-memory inode
+	 * acquiring transaction locks for AFTER records
+	 * on the on-disk inode of file object
+	 *
+	 * sort the inodes array by inode number in descending order
+	 * to prevent deadlock when acquiring transaction lock
+	 * of on-disk inodes on multiple on-disk inode pages by
+	 * multiple concurrent transactions
+	 */
+	for (k = 0; k < cd.nip; k++) {
+		top = (cd.iplist[k])->i_ino;
+		for (n = k + 1; n < cd.nip; n++) {
+			ip = cd.iplist[n];
+			if (ip->i_ino > top) {
+				top = ip->i_ino;
+				cd.iplist[n] = cd.iplist[k];
+				cd.iplist[k] = ip;
+			}
+		}
+
+		ip = cd.iplist[k];
+		jfs_ip = JFS_IP(ip);
+
+		/*
+		 * BUGBUG - This code has temporarily been removed.  The
+		 * intent is to ensure that any file data is written before
+		 * the metadata is committed to the journal.  This prevents
+		 * uninitialized data from appearing in a file after the
+		 * journal has been replayed.  (The uninitialized data
+		 * could be sensitive data removed by another user.)
+		 *
+		 * The problem now is that we are holding the IWRITELOCK
+		 * on the inode, and calling filemap_fdatawrite on an
+		 * unmapped page will cause a deadlock in jfs_get_block.
+		 *
+		 * The long term solution is to pare down the use of
+		 * IWRITELOCK.  We are currently holding it too long.
+		 * We could also be smarter about which data pages need
+		 * to be written before the transaction is committed and
+		 * when we don't need to worry about it at all.
+		 *
+		 * if ((!S_ISDIR(ip->i_mode))
+		 *    && (tblk->flag & COMMIT_DELETE) == 0)
+		 *	filemap_write_and_wait(ip->i_mapping);
+		 */
+
+		/*
+		 * Mark inode as not dirty.  It will still be on the dirty
+		 * inode list, but we'll know not to commit it again unless
+		 * it gets marked dirty again
+		 */
+		clear_cflag(COMMIT_Dirty, ip);
+
+		/* inherit anonymous tlock(s) of inode */
+		if (jfs_ip->atlhead) {
+			lid_to_tlock(jfs_ip->atltail)->next = tblk->next;
+			tblk->next = jfs_ip->atlhead;
+			if (!tblk->last)
+				tblk->last = jfs_ip->atltail;
+			jfs_ip->atlhead = jfs_ip->atltail = 0;
+			TXN_LOCK();
+			list_del_init(&jfs_ip->anon_inode_list);
+			TXN_UNLOCK();
+		}
+
+		/*
+		 * acquire transaction lock on on-disk inode page
+		 * (become first tlock of the tblk's tlock list)
+		 */
+		if (((rc = diWrite(tid, ip))))
+			goto out;
+	}
+
+	/*
+	 *	write log records from transaction locks
+	 *
+	 * txUpdateMap() resets XAD_NEW in XAD.
+	 */
+	txLog(log, tblk, &cd);
+
+	/*
+	 * Ensure that inode isn't reused before
+	 * lazy commit thread finishes processing
+	 */
+	if (tblk->xflag & COMMIT_DELETE) {
+		ihold(tblk->u.ip);
+		/*
+		 * Avoid a rare deadlock
+		 *
+		 * If the inode is locked, we may be blocked in
+		 * jfs_commit_inode.  If so, we don't want the
+		 * lazy_commit thread doing the last iput() on the inode
+		 * since that may block on the locked inode.  Instead,
+		 * commit the transaction synchronously, so the last iput
+		 * will be done by the calling thread (or later)
+		 */
+		/*
+		 * I believe this code is no longer needed.  Splitting I_LOCK
+		 * into two bits, I_NEW and I_SYNC should prevent this
+		 * deadlock as well.  But since I don't have a JFS testload
+		 * to verify this, only a trivial s/I_LOCK/I_SYNC/ was done.
+		 * Joern
+		 */
+		if (tblk->u.ip->i_state & I_SYNC)
+			tblk->xflag &= ~COMMIT_LAZY;
+	}
+
+	ASSERT((!(tblk->xflag & COMMIT_DELETE)) ||
+	       ((tblk->u.ip->i_nlink == 0) &&
+		!test_cflag(COMMIT_Nolink, tblk->u.ip)));
+
+	/*
+	 *	write COMMIT log record
+	 */
+	lrd->type = cpu_to_le16(LOG_COMMIT);
+	lrd->length = 0;
+	lmLog(log, tblk, lrd, NULL);
+
+	lmGroupCommit(log, tblk);
+
+	/*
+	 *	- transaction is now committed -
+	 */
+
+	/*
+	 * force pages in careful update
+	 * (imap addressing structure update)
+	 */
+	if (flag & COMMIT_FORCE)
+		txForce(tblk);
+
+	/*
+	 *	update allocation map.
+	 *
+	 * update inode allocation map and inode:
+	 * free pager lock on memory object of inode if any.
+	 * update block allocation map.
+	 *
+	 * txUpdateMap() resets XAD_NEW in XAD.
+	 */
+	if (tblk->xflag & COMMIT_FORCE)
+		txUpdateMap(tblk);
+
+	/*
+	 *	free transaction locks and pageout/free pages
+	 */
+	txRelease(tblk);
+
+	if ((tblk->flag & tblkGC_LAZY) == 0)
+		txUnlock(tblk);
+
+
+	/*
+	 *	reset in-memory object state
+	 */
+	for (k = 0; k < cd.nip; k++) {
+		ip = cd.iplist[k];
+		jfs_ip = JFS_IP(ip);
+
+		/*
+		 * reset in-memory inode state
+		 */
+		jfs_ip->bxflag = 0;
+		jfs_ip->blid = 0;
+	}
+
+      out:
+	if (rc != 0)
+		txAbort(tid, 1);
+
+      TheEnd:
+	jfs_info("txCommit: tid = %d, returning %d", tid, rc);
+	return rc;
+}
+
+/*
+ * NAME:	txLog()
+ *
+ * FUNCTION:	Writes AFTER log records for all lines modified
+ *		by tid for segments specified by inodes in comdata.
+ *		Code assumes only WRITELOCKS are recorded in lockwords.
+ *
+ * PARAMETERS:
+ *
+ * RETURN :
+ */
+static void txLog(struct jfs_log *log, struct tblock *tblk, struct commit *cd)
+{
+	struct inode *ip;
+	lid_t lid;
+	struct tlock *tlck;
+	struct lrd *lrd = &cd->lrd;
+
+	/*
+	 * write log record(s) for each tlock of transaction,
+	 */
+	for (lid = tblk->next; lid; lid = tlck->next) {
+		tlck = lid_to_tlock(lid);
+
+		tlck->flag |= tlckLOG;
+
+		/* initialize lrd common */
+		ip = tlck->ip;
+		lrd->aggregate = cpu_to_le32(JFS_SBI(ip->i_sb)->aggregate);
+		lrd->log.redopage.fileset = cpu_to_le32(JFS_IP(ip)->fileset);
+		lrd->log.redopage.inode = cpu_to_le32(ip->i_ino);
+
+		/* write log record of page from the tlock */
+		switch (tlck->type & tlckTYPE) {
+		case tlckXTREE:
+			xtLog(log, tblk, lrd, tlck);
+			break;
+
+		case tlckDTREE:
+			dtLog(log, tblk, lrd, tlck);
+			break;
+
+		case tlckINODE:
+			diLog(log, tblk, lrd, tlck, cd);
+			break;
+
+		case tlckMAP:
+			mapLog(log, tblk, lrd, tlck);
+			break;
+
+		case tlckDATA:
+			dataLog(log, tblk, lrd, tlck);
+			break;
+
+		default:
+			jfs_err("UFO tlock:0x%p", tlck);
+		}
+	}
+
+	return;
+}
+
+/*
+ *	diLog()
+ *
+ * function:	log inode tlock and format maplock to update bmap;
+ */
+static void diLog(struct jfs_log *log, struct tblock *tblk, struct lrd *lrd,
+		 struct tlock *tlck, struct commit *cd)
+{
+	struct metapage *mp;
+	pxd_t *pxd;
+	struct pxd_lock *pxdlock;
+
+	mp = tlck->mp;
+
+	/* initialize as REDOPAGE record format */
+	lrd->log.redopage.type = cpu_to_le16(LOG_INODE);
+	lrd->log.redopage.l2linesize = cpu_to_le16(L2INODESLOTSIZE);
+
+	pxd = &lrd->log.redopage.pxd;
+
+	/*
+	 *	inode after image
+	 */
+	if (tlck->type & tlckENTRY) {
+		/* log after-image for logredo(): */
+		lrd->type = cpu_to_le16(LOG_REDOPAGE);
+		PXDaddress(pxd, mp->index);
+		PXDlength(pxd,
+			  mp->logical_size >> tblk->sb->s_blocksize_bits);
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+
+		/* mark page as homeward bound */
+		tlck->flag |= tlckWRITEPAGE;
+	} else if (tlck->type & tlckFREE) {
+		/*
+		 *	free inode extent
+		 *
+		 * (pages of the freed inode extent have been invalidated and
+		 * a maplock for free of the extent has been formatted at
+		 * txLock() time);
+		 *
+		 * the tlock had been acquired on the inode allocation map page
+		 * (iag) that specifies the freed extent, even though the map
+		 * page is not itself logged, to prevent pageout of the map
+		 * page before the log;
+		 */
+
+		/* log LOG_NOREDOINOEXT of the freed inode extent for
+		 * logredo() to start NoRedoPage filters, and to update
+		 * imap and bmap for free of the extent;
+		 */
+		lrd->type = cpu_to_le16(LOG_NOREDOINOEXT);
+		/*
+		 * For the LOG_NOREDOINOEXT record, we need
+		 * to pass the IAG number and inode extent
+		 * index (within that IAG) from which the
+		 * extent is being released.  These have been
+		 * passed to us in the iplist[1] and iplist[2].
+		 */
+		lrd->log.noredoinoext.iagnum =
+		    cpu_to_le32((u32) (size_t) cd->iplist[1]);
+		lrd->log.noredoinoext.inoext_idx =
+		    cpu_to_le32((u32) (size_t) cd->iplist[2]);
+
+		pxdlock = (struct pxd_lock *) & tlck->lock;
+		*pxd = pxdlock->pxd;
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, NULL));
+
+		/* update bmap */
+		tlck->flag |= tlckUPDATEMAP;
+
+		/* mark page as homeward bound */
+		tlck->flag |= tlckWRITEPAGE;
+	} else
+		jfs_err("diLog: UFO type tlck:0x%p", tlck);
+	return;
+}
+
+/*
+ *	dataLog()
+ *
+ * function:	log data tlock
+ */
+static void dataLog(struct jfs_log *log, struct tblock *tblk, struct lrd *lrd,
+	    struct tlock *tlck)
+{
+	struct metapage *mp;
+	pxd_t *pxd;
+
+	mp = tlck->mp;
+
+	/* initialize as REDOPAGE record format */
+	lrd->log.redopage.type = cpu_to_le16(LOG_DATA);
+	lrd->log.redopage.l2linesize = cpu_to_le16(L2DATASLOTSIZE);
+
+	pxd = &lrd->log.redopage.pxd;
+
+	/* log after-image for logredo(): */
+	lrd->type = cpu_to_le16(LOG_REDOPAGE);
+
+	if (jfs_dirtable_inline(tlck->ip)) {
+		/*
+		 * The table has been truncated, we've must have deleted
+		 * the last entry, so don't bother logging this
+		 */
+		mp->lid = 0;
+		grab_metapage(mp);
+		metapage_homeok(mp);
+		discard_metapage(mp);
+		tlck->mp = NULL;
+		return;
+	}
+
+	PXDaddress(pxd, mp->index);
+	PXDlength(pxd, mp->logical_size >> tblk->sb->s_blocksize_bits);
+
+	lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+
+	/* mark page as homeward bound */
+	tlck->flag |= tlckWRITEPAGE;
+
+	return;
+}
+
+/*
+ *	dtLog()
+ *
+ * function:	log dtree tlock and format maplock to update bmap;
+ */
+static void dtLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
+	   struct tlock * tlck)
+{
+	struct metapage *mp;
+	struct pxd_lock *pxdlock;
+	pxd_t *pxd;
+
+	mp = tlck->mp;
+
+	/* initialize as REDOPAGE/NOREDOPAGE record format */
+	lrd->log.redopage.type = cpu_to_le16(LOG_DTREE);
+	lrd->log.redopage.l2linesize = cpu_to_le16(L2DTSLOTSIZE);
+
+	pxd = &lrd->log.redopage.pxd;
+
+	if (tlck->type & tlckBTROOT)
+		lrd->log.redopage.type |= cpu_to_le16(LOG_BTROOT);
+
+	/*
+	 *	page extension via relocation: entry insertion;
+	 *	page extension in-place: entry insertion;
+	 *	new right page from page split, reinitialized in-line
+	 *	root from root page split: entry insertion;
+	 */
+	if (tlck->type & (tlckNEW | tlckEXTEND)) {
+		/* log after-image of the new page for logredo():
+		 * mark log (LOG_NEW) for logredo() to initialize
+		 * freelist and update bmap for alloc of the new page;
+		 */
+		lrd->type = cpu_to_le16(LOG_REDOPAGE);
+		if (tlck->type & tlckEXTEND)
+			lrd->log.redopage.type |= cpu_to_le16(LOG_EXTEND);
+		else
+			lrd->log.redopage.type |= cpu_to_le16(LOG_NEW);
+		PXDaddress(pxd, mp->index);
+		PXDlength(pxd,
+			  mp->logical_size >> tblk->sb->s_blocksize_bits);
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+
+		/* format a maplock for txUpdateMap() to update bPMAP for
+		 * alloc of the new page;
+		 */
+		if (tlck->type & tlckBTROOT)
+			return;
+		tlck->flag |= tlckUPDATEMAP;
+		pxdlock = (struct pxd_lock *) & tlck->lock;
+		pxdlock->flag = mlckALLOCPXD;
+		pxdlock->pxd = *pxd;
+
+		pxdlock->index = 1;
+
+		/* mark page as homeward bound */
+		tlck->flag |= tlckWRITEPAGE;
+		return;
+	}
+
+	/*
+	 *	entry insertion/deletion,
+	 *	sibling page link update (old right page before split);
+	 */
+	if (tlck->type & (tlckENTRY | tlckRELINK)) {
+		/* log after-image for logredo(): */
+		lrd->type = cpu_to_le16(LOG_REDOPAGE);
+		PXDaddress(pxd, mp->index);
+		PXDlength(pxd,
+			  mp->logical_size >> tblk->sb->s_blocksize_bits);
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+
+		/* mark page as homeward bound */
+		tlck->flag |= tlckWRITEPAGE;
+		return;
+	}
+
+	/*
+	 *	page deletion: page has been invalidated
+	 *	page relocation: source extent
+	 *
+	 *	a maplock for free of the page has been formatted
+	 *	at txLock() time);
+	 */
+	if (tlck->type & (tlckFREE | tlckRELOCATE)) {
+		/* log LOG_NOREDOPAGE of the deleted page for logredo()
+		 * to start NoRedoPage filter and to update bmap for free
+		 * of the deletd page
+		 */
+		lrd->type = cpu_to_le16(LOG_NOREDOPAGE);
+		pxdlock = (struct pxd_lock *) & tlck->lock;
+		*pxd = pxdlock->pxd;
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, NULL));
+
+		/* a maplock for txUpdateMap() for free of the page
+		 * has been formatted at txLock() time;
+		 */
+		tlck->flag |= tlckUPDATEMAP;
+	}
+	return;
+}
+
+/*
+ *	xtLog()
+ *
+ * function:	log xtree tlock and format maplock to update bmap;
+ */
+static void xtLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
+	   struct tlock * tlck)
+{
+	struct inode *ip;
+	struct metapage *mp;
+	xtpage_t *p;
+	struct xtlock *xtlck;
+	struct maplock *maplock;
+	struct xdlistlock *xadlock;
+	struct pxd_lock *pxdlock;
+	pxd_t *page_pxd;
+	int next, lwm, hwm;
+
+	ip = tlck->ip;
+	mp = tlck->mp;
+
+	/* initialize as REDOPAGE/NOREDOPAGE record format */
+	lrd->log.redopage.type = cpu_to_le16(LOG_XTREE);
+	lrd->log.redopage.l2linesize = cpu_to_le16(L2XTSLOTSIZE);
+
+	page_pxd = &lrd->log.redopage.pxd;
+
+	if (tlck->type & tlckBTROOT) {
+		lrd->log.redopage.type |= cpu_to_le16(LOG_BTROOT);
+		p = &JFS_IP(ip)->i_xtroot;
+		if (S_ISDIR(ip->i_mode))
+			lrd->log.redopage.type |=
+			    cpu_to_le16(LOG_DIR_XTREE);
+	} else
+		p = (xtpage_t *) mp->data;
+	next = le16_to_cpu(p->header.nextindex);
+
+	xtlck = (struct xtlock *) & tlck->lock;
+
+	maplock = (struct maplock *) & tlck->lock;
+	xadlock = (struct xdlistlock *) maplock;
+
+	/*
+	 *	entry insertion/extension;
+	 *	sibling page link update (old right page before split);
+	 */
+	if (tlck->type & (tlckNEW | tlckGROW | tlckRELINK)) {
+		/* log after-image for logredo():
+		 * logredo() will update bmap for alloc of new/extended
+		 * extents (XAD_NEW|XAD_EXTEND) of XAD[lwm:next) from
+		 * after-image of XADlist;
+		 * logredo() resets (XAD_NEW|XAD_EXTEND) flag when
+		 * applying the after-image to the meta-data page.
+		 */
+		lrd->type = cpu_to_le16(LOG_REDOPAGE);
+		PXDaddress(page_pxd, mp->index);
+		PXDlength(page_pxd,
+			  mp->logical_size >> tblk->sb->s_blocksize_bits);
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+
+		/* format a maplock for txUpdateMap() to update bPMAP
+		 * for alloc of new/extended extents of XAD[lwm:next)
+		 * from the page itself;
+		 * txUpdateMap() resets (XAD_NEW|XAD_EXTEND) flag.
+		 */
+		lwm = xtlck->lwm.offset;
+		if (lwm == 0)
+			lwm = XTPAGEMAXSLOT;
+
+		if (lwm == next)
+			goto out;
+		if (lwm > next) {
+			jfs_err("xtLog: lwm > next");
+			goto out;
+		}
+		tlck->flag |= tlckUPDATEMAP;
+		xadlock->flag = mlckALLOCXADLIST;
+		xadlock->count = next - lwm;
+		if ((xadlock->count <= 4) && (tblk->xflag & COMMIT_LAZY)) {
+			int i;
+			pxd_t *pxd;
+			/*
+			 * Lazy commit may allow xtree to be modified before
+			 * txUpdateMap runs.  Copy xad into linelock to
+			 * preserve correct data.
+			 *
+			 * We can fit twice as may pxd's as xads in the lock
+			 */
+			xadlock->flag = mlckALLOCPXDLIST;
+			pxd = xadlock->xdlist = &xtlck->pxdlock;
+			for (i = 0; i < xadlock->count; i++) {
+				PXDaddress(pxd, addressXAD(&p->xad[lwm + i]));
+				PXDlength(pxd, lengthXAD(&p->xad[lwm + i]));
+				p->xad[lwm + i].flag &=
+				    ~(XAD_NEW | XAD_EXTENDED);
+				pxd++;
+			}
+		} else {
+			/*
+			 * xdlist will point to into inode's xtree, ensure
+			 * that transaction is not committed lazily.
+			 */
+			xadlock->flag = mlckALLOCXADLIST;
+			xadlock->xdlist = &p->xad[lwm];
+			tblk->xflag &= ~COMMIT_LAZY;
+		}
+		jfs_info("xtLog: alloc ip:0x%p mp:0x%p tlck:0x%p lwm:%d count:%d",
+			 tlck->ip, mp, tlck, lwm, xadlock->count);
+
+		maplock->index = 1;
+
+	      out:
+		/* mark page as homeward bound */
+		tlck->flag |= tlckWRITEPAGE;
+
+		return;
+	}
+
+	/*
+	 *	page deletion: file deletion/truncation (ref. xtTruncate())
+	 *
+	 * (page will be invalidated after log is written and bmap
+	 * is updated from the page);
+	 */
+	if (tlck->type & tlckFREE) {
+		/* LOG_NOREDOPAGE log for NoRedoPage filter:
+		 * if page free from file delete, NoRedoFile filter from
+		 * inode image of zero link count will subsume NoRedoPage
+		 * filters for each page;
+		 * if page free from file truncattion, write NoRedoPage
+		 * filter;
+		 *
+		 * upadte of block allocation map for the page itself:
+		 * if page free from deletion and truncation, LOG_UPDATEMAP
+		 * log for the page itself is generated from processing
+		 * its parent page xad entries;
+		 */
+		/* if page free from file truncation, log LOG_NOREDOPAGE
+		 * of the deleted page for logredo() to start NoRedoPage
+		 * filter for the page;
+		 */
+		if (tblk->xflag & COMMIT_TRUNCATE) {
+			/* write NOREDOPAGE for the page */
+			lrd->type = cpu_to_le16(LOG_NOREDOPAGE);
+			PXDaddress(page_pxd, mp->index);
+			PXDlength(page_pxd,
+				  mp->logical_size >> tblk->sb->
+				  s_blocksize_bits);
+			lrd->backchain =
+			    cpu_to_le32(lmLog(log, tblk, lrd, NULL));
+
+			if (tlck->type & tlckBTROOT) {
+				/* Empty xtree must be logged */
+				lrd->type = cpu_to_le16(LOG_REDOPAGE);
+				lrd->backchain =
+				    cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+			}
+		}
+
+		/* init LOG_UPDATEMAP of the freed extents
+		 * XAD[XTENTRYSTART:hwm) from the deleted page itself
+		 * for logredo() to update bmap;
+		 */
+		lrd->type = cpu_to_le16(LOG_UPDATEMAP);
+		lrd->log.updatemap.type = cpu_to_le16(LOG_FREEXADLIST);
+		xtlck = (struct xtlock *) & tlck->lock;
+		hwm = xtlck->hwm.offset;
+		lrd->log.updatemap.nxd =
+		    cpu_to_le16(hwm - XTENTRYSTART + 1);
+		/* reformat linelock for lmLog() */
+		xtlck->header.offset = XTENTRYSTART;
+		xtlck->header.length = hwm - XTENTRYSTART + 1;
+		xtlck->index = 1;
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+
+		/* format a maplock for txUpdateMap() to update bmap
+		 * to free extents of XAD[XTENTRYSTART:hwm) from the
+		 * deleted page itself;
+		 */
+		tlck->flag |= tlckUPDATEMAP;
+		xadlock->count = hwm - XTENTRYSTART + 1;
+		if ((xadlock->count <= 4) && (tblk->xflag & COMMIT_LAZY)) {
+			int i;
+			pxd_t *pxd;
+			/*
+			 * Lazy commit may allow xtree to be modified before
+			 * txUpdateMap runs.  Copy xad into linelock to
+			 * preserve correct data.
+			 *
+			 * We can fit twice as may pxd's as xads in the lock
+			 */
+			xadlock->flag = mlckFREEPXDLIST;
+			pxd = xadlock->xdlist = &xtlck->pxdlock;
+			for (i = 0; i < xadlock->count; i++) {
+				PXDaddress(pxd,
+					addressXAD(&p->xad[XTENTRYSTART + i]));
+				PXDlength(pxd,
+					lengthXAD(&p->xad[XTENTRYSTART + i]));
+				pxd++;
+			}
+		} else {
+			/*
+			 * xdlist will point to into inode's xtree, ensure
+			 * that transaction is not committed lazily.
+			 */
+			xadlock->flag = mlckFREEXADLIST;
+			xadlock->xdlist = &p->xad[XTENTRYSTART];
+			tblk->xflag &= ~COMMIT_LAZY;
+		}
+		jfs_info("xtLog: free ip:0x%p mp:0x%p count:%d lwm:2",
+			 tlck->ip, mp, xadlock->count);
+
+		maplock->index = 1;
+
+		/* mark page as invalid */
+		if (((tblk->xflag & COMMIT_PWMAP) || S_ISDIR(ip->i_mode))
+		    && !(tlck->type & tlckBTROOT))
+			tlck->flag |= tlckFREEPAGE;
+		/*
+		   else (tblk->xflag & COMMIT_PMAP)
+		   ? release the page;
+		 */
+		return;
+	}
+
+	/*
+	 *	page/entry truncation: file truncation (ref. xtTruncate())
+	 *
+	 *	|----------+------+------+---------------|
+	 *		   |      |      |
+	 *		   |      |     hwm - hwm before truncation
+	 *		   |     next - truncation point
+	 *		  lwm - lwm before truncation
+	 * header ?
+	 */
+	if (tlck->type & tlckTRUNCATE) {
+		pxd_t pxd;	/* truncated extent of xad */
+		int twm;
+
+		/*
+		 * For truncation the entire linelock may be used, so it would
+		 * be difficult to store xad list in linelock itself.
+		 * Therefore, we'll just force transaction to be committed
+		 * synchronously, so that xtree pages won't be changed before
+		 * txUpdateMap runs.
+		 */
+		tblk->xflag &= ~COMMIT_LAZY;
+		lwm = xtlck->lwm.offset;
+		if (lwm == 0)
+			lwm = XTPAGEMAXSLOT;
+		hwm = xtlck->hwm.offset;
+		twm = xtlck->twm.offset;
+
+		/*
+		 *	write log records
+		 */
+		/* log after-image for logredo():
+		 *
+		 * logredo() will update bmap for alloc of new/extended
+		 * extents (XAD_NEW|XAD_EXTEND) of XAD[lwm:next) from
+		 * after-image of XADlist;
+		 * logredo() resets (XAD_NEW|XAD_EXTEND) flag when
+		 * applying the after-image to the meta-data page.
+		 */
+		lrd->type = cpu_to_le16(LOG_REDOPAGE);
+		PXDaddress(page_pxd, mp->index);
+		PXDlength(page_pxd,
+			  mp->logical_size >> tblk->sb->s_blocksize_bits);
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+
+		/*
+		 * truncate entry XAD[twm == next - 1]:
+		 */
+		if (twm == next - 1) {
+			/* init LOG_UPDATEMAP for logredo() to update bmap for
+			 * free of truncated delta extent of the truncated
+			 * entry XAD[next - 1]:
+			 * (xtlck->pxdlock = truncated delta extent);
+			 */
+			pxdlock = (struct pxd_lock *) & xtlck->pxdlock;
+			/* assert(pxdlock->type & tlckTRUNCATE); */
+			lrd->type = cpu_to_le16(LOG_UPDATEMAP);
+			lrd->log.updatemap.type = cpu_to_le16(LOG_FREEPXD);
+			lrd->log.updatemap.nxd = cpu_to_le16(1);
+			lrd->log.updatemap.pxd = pxdlock->pxd;
+			pxd = pxdlock->pxd;	/* save to format maplock */
+			lrd->backchain =
+			    cpu_to_le32(lmLog(log, tblk, lrd, NULL));
+		}
+
+		/*
+		 * free entries XAD[next:hwm]:
+		 */
+		if (hwm >= next) {
+			/* init LOG_UPDATEMAP of the freed extents
+			 * XAD[next:hwm] from the deleted page itself
+			 * for logredo() to update bmap;
+			 */
+			lrd->type = cpu_to_le16(LOG_UPDATEMAP);
+			lrd->log.updatemap.type =
+			    cpu_to_le16(LOG_FREEXADLIST);
+			xtlck = (struct xtlock *) & tlck->lock;
+			hwm = xtlck->hwm.offset;
+			lrd->log.updatemap.nxd =
+			    cpu_to_le16(hwm - next + 1);
+			/* reformat linelock for lmLog() */
+			xtlck->header.offset = next;
+			xtlck->header.length = hwm - next + 1;
+			xtlck->index = 1;
+			lrd->backchain =
+			    cpu_to_le32(lmLog(log, tblk, lrd, tlck));
+		}
+
+		/*
+		 *	format maplock(s) for txUpdateMap() to update bmap
+		 */
+		maplock->index = 0;
+
+		/*
+		 * allocate entries XAD[lwm:next):
+		 */
+		if (lwm < next) {
+			/* format a maplock for txUpdateMap() to update bPMAP
+			 * for alloc of new/extended extents of XAD[lwm:next)
+			 * from the page itself;
+			 * txUpdateMap() resets (XAD_NEW|XAD_EXTEND) flag.
+			 */
+			tlck->flag |= tlckUPDATEMAP;
+			xadlock->flag = mlckALLOCXADLIST;
+			xadlock->count = next - lwm;
+			xadlock->xdlist = &p->xad[lwm];
+
+			jfs_info("xtLog: alloc ip:0x%p mp:0x%p count:%d lwm:%d next:%d",
+				 tlck->ip, mp, xadlock->count, lwm, next);
+			maplock->index++;
+			xadlock++;
+		}
+
+		/*
+		 * truncate entry XAD[twm == next - 1]:
+		 */
+		if (twm == next - 1) {
+			/* format a maplock for txUpdateMap() to update bmap
+			 * to free truncated delta extent of the truncated
+			 * entry XAD[next - 1];
+			 * (xtlck->pxdlock = truncated delta extent);
+			 */
+			tlck->flag |= tlckUPDATEMAP;
+			pxdlock = (struct pxd_lock *) xadlock;
+			pxdlock->flag = mlckFREEPXD;
+			pxdlock->count = 1;
+			pxdlock->pxd = pxd;
+
+			jfs_info("xtLog: truncate ip:0x%p mp:0x%p count:%d hwm:%d",
+				 ip, mp, pxdlock->count, hwm);
+			maplock->index++;
+			xadlock++;
+		}
+
+		/*
+		 * free entries XAD[next:hwm]:
+		 */
+		if (hwm >= next) {
+			/* format a maplock for txUpdateMap() to update bmap
+			 * to free extents of XAD[next:hwm] from thedeleted
+			 * page itself;
+			 */
+			tlck->flag |= tlckUPDATEMAP;
+			xadlock->flag = mlckFREEXADLIST;
+			xadlock->count = hwm - next + 1;
+			xadlock->xdlist = &p->xad[next];
+
+			jfs_info("xtLog: free ip:0x%p mp:0x%p count:%d next:%d hwm:%d",
+				 tlck->ip, mp, xadlock->count, next, hwm);
+			maplock->index++;
+		}
+
+		/* mark page as homeward bound */
+		tlck->flag |= tlckWRITEPAGE;
+	}
+	return;
+}
+
+/*
+ *	mapLog()
+ *
+ * function:	log from maplock of freed data extents;
+ */
+static void mapLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
+		   struct tlock * tlck)
+{
+	struct pxd_lock *pxdlock;
+	int i, nlock;
+	pxd_t *pxd;
+
+	/*
+	 *	page relocation: free the source page extent
+	 *
+	 * a maplock for txUpdateMap() for free of the page
+	 * has been formatted at txLock() time saving the src
+	 * relocated page address;
+	 */
+	if (tlck->type & tlckRELOCATE) {
+		/* log LOG_NOREDOPAGE of the old relocated page
+		 * for logredo() to start NoRedoPage filter;
+		 */
+		lrd->type = cpu_to_le16(LOG_NOREDOPAGE);
+		pxdlock = (struct pxd_lock *) & tlck->lock;
+		pxd = &lrd->log.redopage.pxd;
+		*pxd = pxdlock->pxd;
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, NULL));
+
+		/* (N.B. currently, logredo() does NOT update bmap
+		 * for free of the page itself for (LOG_XTREE|LOG_NOREDOPAGE);
+		 * if page free from relocation, LOG_UPDATEMAP log is
+		 * specifically generated now for logredo()
+		 * to update bmap for free of src relocated page;
+		 * (new flag LOG_RELOCATE may be introduced which will
+		 * inform logredo() to start NORedoPage filter and also
+		 * update block allocation map at the same time, thus
+		 * avoiding an extra log write);
+		 */
+		lrd->type = cpu_to_le16(LOG_UPDATEMAP);
+		lrd->log.updatemap.type = cpu_to_le16(LOG_FREEPXD);
+		lrd->log.updatemap.nxd = cpu_to_le16(1);
+		lrd->log.updatemap.pxd = pxdlock->pxd;
+		lrd->backchain = cpu_to_le32(lmLog(log, tblk, lrd, NULL));
+
+		/* a maplock for txUpdateMap() for free of the page
+		 * has been formatted at txLock() time;
+		 */
+		tlck->flag |= tlckUPDATEMAP;
+		return;
+	}
+	/*
+
+	 * Otherwise it's not a relocate request
+	 *
+	 */
+	else {
+		/* log LOG_UPDATEMAP for logredo() to update bmap for
+		 * free of truncated/relocated delta extent of the data;
+		 * e.g.: external EA extent, relocated/truncated extent
+		 * from xtTailgate();
+		 */
+		lrd->type = cpu_to_le16(LOG_UPDATEMAP);
+		pxdlock = (struct pxd_lock *) & tlck->lock;
+		nlock = pxdlock->index;
+		for (i = 0; i < nlock; i++, pxdlock++) {
+			if (pxdlock->flag & mlckALLOCPXD)
+				lrd->log.updatemap.type =
+				    cpu_to_le16(LOG_ALLOCPXD);
+			else
+				lrd->log.updatemap.type =
+				    cpu_to_le16(LOG_FREEPXD);
+			lrd->log.updatemap.nxd = cpu_to_le16(1);
+			lrd->log.updatemap.pxd = pxdlock->pxd;
+			lrd->backchain =
+			    cpu_to_le32(lmLog(log, tblk, lrd, NULL));
+			jfs_info("mapLog: xaddr:0x%lx xlen:0x%x",
+				 (ulong) addressPXD(&pxdlock->pxd),
+				 lengthPXD(&pxdlock->pxd));
+		}
+
+		/* update bmap */
+		tlck->flag |= tlckUPDATEMAP;
+	}
+}
+
+/*
+ *	txEA()
+ *
+ * function:	acquire maplock for EA/ACL extents or
+ *		set COMMIT_INLINE flag;
+ */
+void txEA(tid_t tid, struct inode *ip, dxd_t * oldea, dxd_t * newea)
+{
+	struct tlock *tlck = NULL;
+	struct pxd_lock *maplock = NULL, *pxdlock = NULL;
+
+	/*
+	 * format maplock for alloc of new EA extent
+	 */
+	if (newea) {
+		/* Since the newea could be a completely zeroed entry we need to
+		 * check for the two flags which indicate we should actually
+		 * commit new EA data
+		 */
+		if (newea->flag & DXD_EXTENT) {
+			tlck = txMaplock(tid, ip, tlckMAP);
+			maplock = (struct pxd_lock *) & tlck->lock;
+			pxdlock = (struct pxd_lock *) maplock;
+			pxdlock->flag = mlckALLOCPXD;
+			PXDaddress(&pxdlock->pxd, addressDXD(newea));
+			PXDlength(&pxdlock->pxd, lengthDXD(newea));
+			pxdlock++;
+			maplock->index = 1;
+		} else if (newea->flag & DXD_INLINE) {
+			tlck = NULL;
+
+			set_cflag(COMMIT_Inlineea, ip);
+		}
+	}
+
+	/*
+	 * format maplock for free of old EA extent
+	 */
+	if (!test_cflag(COMMIT_Nolink, ip) && oldea->flag & DXD_EXTENT) {
+		if (tlck == NULL) {
+			tlck = txMaplock(tid, ip, tlckMAP);
+			maplock = (struct pxd_lock *) & tlck->lock;
+			pxdlock = (struct pxd_lock *) maplock;
+			maplock->index = 0;
+		}
+		pxdlock->flag = mlckFREEPXD;
+		PXDaddress(&pxdlock->pxd, addressDXD(oldea));
+		PXDlength(&pxdlock->pxd, lengthDXD(oldea));
+		maplock->index++;
+	}
+}
+
+/*
+ *	txForce()
+ *
+ * function: synchronously write pages locked by transaction
+ *	     after txLog() but before txUpdateMap();
+ */
+static void txForce(struct tblock * tblk)
+{
+	struct tlock *tlck;
+	lid_t lid, next;
+	struct metapage *mp;
+
+	/*
+	 * reverse the order of transaction tlocks in
+	 * careful update order of address index pages
+	 * (right to left, bottom up)
+	 */
+	tlck = lid_to_tlock(tblk->next);
+	lid = tlck->next;
+	tlck->next = 0;
+	while (lid) {
+		tlck = lid_to_tlock(lid);
+		next = tlck->next;
+		tlck->next = tblk->next;
+		tblk->next = lid;
+		lid = next;
+	}
+
+	/*
+	 * synchronously write the page, and
+	 * hold the page for txUpdateMap();
+	 */
+	for (lid = tblk->next; lid; lid = next) {
+		tlck = lid_to_tlock(lid);
+		next = tlck->next;
+
+		if ((mp = tlck->mp) != NULL &&
+		    (tlck->type & tlckBTROOT) == 0) {
+			assert(mp->xflag & COMMIT_PAGE);
+
+			if (tlck->flag & tlckWRITEPAGE) {
+				tlck->flag &= ~tlckWRITEPAGE;
+
+				/* do not release page to freelist */
+				force_metapage(mp);
+#if 0
+				/*
+				 * The "right" thing to do here is to
+				 * synchronously write the metadata.
+				 * With the current implementation this
+				 * is hard since write_metapage requires
+				 * us to kunmap & remap the page.  If we
+				 * have tlocks pointing into the metadata
+				 * pages, we don't want to do this.  I think
+				 * we can get by with synchronously writing
+				 * the pages when they are released.
+				 */
+				assert(mp->nohomeok);
+				set_bit(META_dirty, &mp->flag);
+				set_bit(META_sync, &mp->flag);
+#endif
+			}
+		}
+	}
+}
+
+/*
+ *	txUpdateMap()
+ *
+ * function:	update persistent allocation map (and working map
+ *		if appropriate);
+ *
+ * parameter:
+ */
+static void txUpdateMap(struct tblock * tblk)
+{
+	struct inode *ip;
+	struct inode *ipimap;
+	lid_t lid;
+	struct tlock *tlck;
+	struct maplock *maplock;
+	struct pxd_lock pxdlock;
+	int maptype;
+	int k, nlock;
+	struct metapage *mp = NULL;
+
+	ipimap = JFS_SBI(tblk->sb)->ipimap;
+
+	maptype = (tblk->xflag & COMMIT_PMAP) ? COMMIT_PMAP : COMMIT_PWMAP;
+
+
+	/*
+	 *	update block allocation map
+	 *
+	 * update allocation state in pmap (and wmap) and
+	 * update lsn of the pmap page;
+	 */
+	/*
+	 * scan each tlock/page of transaction for block allocation/free:
+	 *
+	 * for each tlock/page of transaction, update map.
+	 *  ? are there tlock for pmap and pwmap at the same time ?
+	 */
+	for (lid = tblk->next; lid; lid = tlck->next) {
+		tlck = lid_to_tlock(lid);
+
+		if ((tlck->flag & tlckUPDATEMAP) == 0)
+			continue;
+
+		if (tlck->flag & tlckFREEPAGE) {
+			/*
+			 * Another thread may attempt to reuse freed space
+			 * immediately, so we want to get rid of the metapage
+			 * before anyone else has a chance to get it.
+			 * Lock metapage, update maps, then invalidate
+			 * the metapage.
+			 */
+			mp = tlck->mp;
+			ASSERT(mp->xflag & COMMIT_PAGE);
+			grab_metapage(mp);
+		}
+
+		/*
+		 * extent list:
+		 * . in-line PXD list:
+		 * . out-of-line XAD list:
+		 */
+		maplock = (struct maplock *) & tlck->lock;
+		nlock = maplock->index;
+
+		for (k = 0; k < nlock; k++, maplock++) {
+			/*
+			 * allocate blocks in persistent map:
+			 *
+			 * blocks have been allocated from wmap at alloc time;
+			 */
+			if (maplock->flag & mlckALLOC) {
+				txAllocPMap(ipimap, maplock, tblk);
+			}
+			/*
+			 * free blocks in persistent and working map:
+			 * blocks will be freed in pmap and then in wmap;
+			 *
+			 * ? tblock specifies the PMAP/PWMAP based upon
+			 * transaction
+			 *
+			 * free blocks in persistent map:
+			 * blocks will be freed from wmap at last reference
+			 * release of the object for regular files;
+			 *
+			 * Alway free blocks from both persistent & working
+			 * maps for directories
+			 */
+			else {	/* (maplock->flag & mlckFREE) */
+
+				if (tlck->flag & tlckDIRECTORY)
+					txFreeMap(ipimap, maplock,
+						  tblk, COMMIT_PWMAP);
+				else
+					txFreeMap(ipimap, maplock,
+						  tblk, maptype);
+			}
+		}
+		if (tlck->flag & tlckFREEPAGE) {
+			if (!(tblk->flag & tblkGC_LAZY)) {
+				/* This is equivalent to txRelease */
+				ASSERT(mp->lid == lid);
+				tlck->mp->lid = 0;
+			}
+			assert(mp->nohomeok == 1);
+			metapage_homeok(mp);
+			discard_metapage(mp);
+			tlck->mp = NULL;
+		}
+	}
+	/*
+	 *	update inode allocation map
+	 *
+	 * update allocation state in pmap and
+	 * update lsn of the pmap page;
+	 * update in-memory inode flag/state
+	 *
+	 * unlock mapper/write lock
+	 */
+	if (tblk->xflag & COMMIT_CREATE) {
+		diUpdatePMap(ipimap, tblk->ino, false, tblk);
+		/* update persistent block allocation map
+		 * for the allocation of inode extent;
+		 */
+		pxdlock.flag = mlckALLOCPXD;
+		pxdlock.pxd = tblk->u.ixpxd;
+		pxdlock.index = 1;
+		txAllocPMap(ipimap, (struct maplock *) & pxdlock, tblk);
+	} else if (tblk->xflag & COMMIT_DELETE) {
+		ip = tblk->u.ip;
+		diUpdatePMap(ipimap, ip->i_ino, true, tblk);
+		iput(ip);
+	}
+}
+
+/*
+ *	txAllocPMap()
+ *
+ * function: allocate from persistent map;
+ *
+ * parameter:
+ *	ipbmap	-
+ *	malock	-
+ *		xad list:
+ *		pxd:
+ *
+ *	maptype -
+ *		allocate from persistent map;
+ *		free from persistent map;
+ *		(e.g., tmp file - free from working map at releae
+ *		 of last reference);
+ *		free from persistent and working map;
+ *
+ *	lsn	- log sequence number;
+ */
+static void txAllocPMap(struct inode *ip, struct maplock * maplock,
+			struct tblock * tblk)
+{
+	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
+	struct xdlistlock *xadlistlock;
+	xad_t *xad;
+	s64 xaddr;
+	int xlen;
+	struct pxd_lock *pxdlock;
+	struct xdlistlock *pxdlistlock;
+	pxd_t *pxd;
+	int n;
+
+	/*
+	 * allocate from persistent map;
+	 */
+	if (maplock->flag & mlckALLOCXADLIST) {
+		xadlistlock = (struct xdlistlock *) maplock;
+		xad = xadlistlock->xdlist;
+		for (n = 0; n < xadlistlock->count; n++, xad++) {
+			if (xad->flag & (XAD_NEW | XAD_EXTENDED)) {
+				xaddr = addressXAD(xad);
+				xlen = lengthXAD(xad);
+				dbUpdatePMap(ipbmap, false, xaddr,
+					     (s64) xlen, tblk);
+				xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
+				jfs_info("allocPMap: xaddr:0x%lx xlen:%d",
+					 (ulong) xaddr, xlen);
+			}
+		}
+	} else if (maplock->flag & mlckALLOCPXD) {
+		pxdlock = (struct pxd_lock *) maplock;
+		xaddr = addressPXD(&pxdlock->pxd);
+		xlen = lengthPXD(&pxdlock->pxd);
+		dbUpdatePMap(ipbmap, false, xaddr, (s64) xlen, tblk);
+		jfs_info("allocPMap: xaddr:0x%lx xlen:%d", (ulong) xaddr, xlen);
+	} else {		/* (maplock->flag & mlckALLOCPXDLIST) */
+
+		pxdlistlock = (struct xdlistlock *) maplock;
+		pxd = pxdlistlock->xdlist;
+		for (n = 0; n < pxdlistlock->count; n++, pxd++) {
+			xaddr = addressPXD(pxd);
+			xlen = lengthPXD(pxd);
+			dbUpdatePMap(ipbmap, false, xaddr, (s64) xlen,
+				     tblk);
+			jfs_info("allocPMap: xaddr:0x%lx xlen:%d",
+				 (ulong) xaddr, xlen);
+		}
+	}
+}
+
+/*
+ *	txFreeMap()
+ *
+ * function:	free from persistent and/or working map;
+ *
+ * todo: optimization
+ */
+void txFreeMap(struct inode *ip,
+	       struct maplock * maplock, struct tblock * tblk, int maptype)
+{
+	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
+	struct xdlistlock *xadlistlock;
+	xad_t *xad;
+	s64 xaddr;
+	int xlen;
+	struct pxd_lock *pxdlock;
+	struct xdlistlock *pxdlistlock;
+	pxd_t *pxd;
+	int n;
+
+	jfs_info("txFreeMap: tblk:0x%p maplock:0x%p maptype:0x%x",
+		 tblk, maplock, maptype);
+
+	/*
+	 * free from persistent map;
+	 */
+	if (maptype == COMMIT_PMAP || maptype == COMMIT_PWMAP) {
+		if (maplock->flag & mlckFREEXADLIST) {
+			xadlistlock = (struct xdlistlock *) maplock;
+			xad = xadlistlock->xdlist;
+			for (n = 0; n < xadlistlock->count; n++, xad++) {
+				if (!(xad->flag & XAD_NEW)) {
+					xaddr = addressXAD(xad);
+					xlen = lengthXAD(xad);
+					dbUpdatePMap(ipbmap, true, xaddr,
+						     (s64) xlen, tblk);
+					jfs_info("freePMap: xaddr:0x%lx xlen:%d",
+						 (ulong) xaddr, xlen);
+				}
+			}
+		} else if (maplock->flag & mlckFREEPXD) {
+			pxdlock = (struct pxd_lock *) maplock;
+			xaddr = addressPXD(&pxdlock->pxd);
+			xlen = lengthPXD(&pxdlock->pxd);
+			dbUpdatePMap(ipbmap, true, xaddr, (s64) xlen,
+				     tblk);
+			jfs_info("freePMap: xaddr:0x%lx xlen:%d",
+				 (ulong) xaddr, xlen);
+		} else {	/* (maplock->flag & mlckALLOCPXDLIST) */
+
+			pxdlistlock = (struct xdlistlock *) maplock;
+			pxd = pxdlistlock->xdlist;
+			for (n = 0; n < pxdlistlock->count; n++, pxd++) {
+				xaddr = addressPXD(pxd);
+				xlen = lengthPXD(pxd);
+				dbUpdatePMap(ipbmap, true, xaddr,
+					     (s64) xlen, tblk);
+				jfs_info("freePMap: xaddr:0x%lx xlen:%d",
+					 (ulong) xaddr, xlen);
+			}
+		}
+	}
+
+	/*
+	 * free from working map;
+	 */
+	if (maptype == COMMIT_PWMAP || maptype == COMMIT_WMAP) {
+		if (maplock->flag & mlckFREEXADLIST) {
+			xadlistlock = (struct xdlistlock *) maplock;
+			xad = xadlistlock->xdlist;
+			for (n = 0; n < xadlistlock->count; n++, xad++) {
+				xaddr = addressXAD(xad);
+				xlen = lengthXAD(xad);
+				dbFree(ip, xaddr, (s64) xlen);
+				xad->flag = 0;
+				jfs_info("freeWMap: xaddr:0x%lx xlen:%d",
+					 (ulong) xaddr, xlen);
+			}
+		} else if (maplock->flag & mlckFREEPXD) {
+			pxdlock = (struct pxd_lock *) maplock;
+			xaddr = addressPXD(&pxdlock->pxd);
+			xlen = lengthPXD(&pxdlock->pxd);
+			dbFree(ip, xaddr, (s64) xlen);
+			jfs_info("freeWMap: xaddr:0x%lx xlen:%d",
+				 (ulong) xaddr, xlen);
+		} else {	/* (maplock->flag & mlckFREEPXDLIST) */
+
+			pxdlistlock = (struct xdlistlock *) maplock;
+			pxd = pxdlistlock->xdlist;
+			for (n = 0; n < pxdlistlock->count; n++, pxd++) {
+				xaddr = addressPXD(pxd);
+				xlen = lengthPXD(pxd);
+				dbFree(ip, xaddr, (s64) xlen);
+				jfs_info("freeWMap: xaddr:0x%lx xlen:%d",
+					 (ulong) xaddr, xlen);
+			}
+		}
+	}
+}
+
+/*
+ *	txFreelock()
+ *
+ * function:	remove tlock from inode anonymous locklist
+ */
+void txFreelock(struct inode *ip)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	struct tlock *xtlck, *tlck;
+	lid_t xlid = 0, lid;
+
+	if (!jfs_ip->atlhead)
+		return;
+
+	TXN_LOCK();
+	xtlck = (struct tlock *) &jfs_ip->atlhead;
+
+	while ((lid = xtlck->next) != 0) {
+		tlck = lid_to_tlock(lid);
+		if (tlck->flag & tlckFREELOCK) {
+			xtlck->next = tlck->next;
+			txLockFree(lid);
+		} else {
+			xtlck = tlck;
+			xlid = lid;
+		}
+	}
+
+	if (jfs_ip->atlhead)
+		jfs_ip->atltail = xlid;
+	else {
+		jfs_ip->atltail = 0;
+		/*
+		 * If inode was on anon_list, remove it
+		 */
+		list_del_init(&jfs_ip->anon_inode_list);
+	}
+	TXN_UNLOCK();
+}
+
+/*
+ *	txAbort()
+ *
+ * function: abort tx before commit;
+ *
+ * frees line-locks and segment locks for all
+ * segments in comdata structure.
+ * Optionally sets state of file-system to FM_DIRTY in super-block.
+ * log age of page-frames in memory for which caller has
+ * are reset to 0 (to avoid logwarap).
+ */
+void txAbort(tid_t tid, int dirty)
+{
+	lid_t lid, next;
+	struct metapage *mp;
+	struct tblock *tblk = tid_to_tblock(tid);
+	struct tlock *tlck;
+
+	/*
+	 * free tlocks of the transaction
+	 */
+	for (lid = tblk->next; lid; lid = next) {
+		tlck = lid_to_tlock(lid);
+		next = tlck->next;
+		mp = tlck->mp;
+		JFS_IP(tlck->ip)->xtlid = 0;
+
+		if (mp) {
+			mp->lid = 0;
+
+			/*
+			 * reset lsn of page to avoid logwarap:
+			 *
+			 * (page may have been previously committed by another
+			 * transaction(s) but has not been paged, i.e.,
+			 * it may be on logsync list even though it has not
+			 * been logged for the current tx.)
+			 */
+			if (mp->xflag & COMMIT_PAGE && mp->lsn)
+				LogSyncRelease(mp);
+		}
+		/* insert tlock at head of freelist */
+		TXN_LOCK();
+		txLockFree(lid);
+		TXN_UNLOCK();
+	}
+
+	/* caller will free the transaction block */
+
+	tblk->next = tblk->last = 0;
+
+	/*
+	 * mark filesystem dirty
+	 */
+	if (dirty)
+		jfs_error(tblk->sb, "\n");
+
+	return;
+}
+
+/*
+ *	txLazyCommit(void)
+ *
+ *	All transactions except those changing ipimap (COMMIT_FORCE) are
+ *	processed by this routine.  This insures that the inode and block
+ *	allocation maps are updated in order.  For synchronous transactions,
+ *	let the user thread finish processing after txUpdateMap() is called.
+ */
+static void txLazyCommit(struct tblock * tblk)
+{
+	struct jfs_log *log;
+
+	while (((tblk->flag & tblkGC_READY) == 0) &&
+	       ((tblk->flag & tblkGC_UNLOCKED) == 0)) {
+		/* We must have gotten ahead of the user thread
+		 */
+		jfs_info("jfs_lazycommit: tblk 0x%p not unlocked", tblk);
+		yield();
+	}
+
+	jfs_info("txLazyCommit: processing tblk 0x%p", tblk);
+
+	txUpdateMap(tblk);
+
+	log = (struct jfs_log *) JFS_SBI(tblk->sb)->log;
+
+	spin_lock_irq(&log->gclock);	// LOGGC_LOCK
+
+	tblk->flag |= tblkGC_COMMITTED;
+
+	if (tblk->flag & tblkGC_READY)
+		log->gcrtc--;
+
+	wake_up_all(&tblk->gcwait);	// LOGGC_WAKEUP
+
+	/*
+	 * Can't release log->gclock until we've tested tblk->flag
+	 */
+	if (tblk->flag & tblkGC_LAZY) {
+		spin_unlock_irq(&log->gclock);	// LOGGC_UNLOCK
+		txUnlock(tblk);
+		tblk->flag &= ~tblkGC_LAZY;
+		txEnd(tblk - TxBlock);	/* Convert back to tid */
+	} else
+		spin_unlock_irq(&log->gclock);	// LOGGC_UNLOCK
+
+	jfs_info("txLazyCommit: done: tblk = 0x%p", tblk);
+}
+
+/*
+ *	jfs_lazycommit(void)
+ *
+ *	To be run as a kernel daemon.  If lbmIODone is called in an interrupt
+ *	context, or where blocking is not wanted, this routine will process
+ *	committed transactions from the unlock queue.
+ */
+int jfs_lazycommit(void *arg)
+{
+	int WorkDone;
+	struct tblock *tblk;
+	unsigned long flags;
+	struct jfs_sb_info *sbi;
+
+	do {
+		LAZY_LOCK(flags);
+		jfs_commit_thread_waking = 0;	/* OK to wake another thread */
+		while (!list_empty(&TxAnchor.unlock_queue)) {
+			WorkDone = 0;
+			list_for_each_entry(tblk, &TxAnchor.unlock_queue,
+					    cqueue) {
+
+				sbi = JFS_SBI(tblk->sb);
+				/*
+				 * For each volume, the transactions must be
+				 * handled in order.  If another commit thread
+				 * is handling a tblk for this superblock,
+				 * skip it
+				 */
+				if (sbi->commit_state & IN_LAZYCOMMIT)
+					continue;
+
+				sbi->commit_state |= IN_LAZYCOMMIT;
+				WorkDone = 1;
+
+				/*
+				 * Remove transaction from queue
+				 */
+				list_del(&tblk->cqueue);
+
+				LAZY_UNLOCK(flags);
+				txLazyCommit(tblk);
+				LAZY_LOCK(flags);
+
+				sbi->commit_state &= ~IN_LAZYCOMMIT;
+				/*
+				 * Don't continue in the for loop.  (We can't
+				 * anyway, it's unsafe!)  We want to go back to
+				 * the beginning of the list.
+				 */
+				break;
+			}
+
+			/* If there was nothing to do, don't continue */
+			if (!WorkDone)
+				break;
+		}
+		/* In case a wakeup came while all threads were active */
+		jfs_commit_thread_waking = 0;
+
+		if (freezing(current)) {
+			LAZY_UNLOCK(flags);
+			try_to_freeze();
+		} else {
+			DECLARE_WAITQUEUE(wq, current);
+
+			add_wait_queue(&jfs_commit_thread_wait, &wq);
+			set_current_state(TASK_INTERRUPTIBLE);
+			LAZY_UNLOCK(flags);
+			schedule();
+			remove_wait_queue(&jfs_commit_thread_wait, &wq);
+		}
+	} while (!kthread_should_stop());
+
+	if (!list_empty(&TxAnchor.unlock_queue))
+		jfs_err("jfs_lazycommit being killed w/pending transactions!");
+	else
+		jfs_info("jfs_lazycommit being killed");
+	return 0;
+}
+
+void txLazyUnlock(struct tblock * tblk)
+{
+	unsigned long flags;
+
+	LAZY_LOCK(flags);
+
+	list_add_tail(&tblk->cqueue, &TxAnchor.unlock_queue);
+	/*
+	 * Don't wake up a commit thread if there is already one servicing
+	 * this superblock, or if the last one we woke up hasn't started yet.
+	 */
+	if (!(JFS_SBI(tblk->sb)->commit_state & IN_LAZYCOMMIT) &&
+	    !jfs_commit_thread_waking) {
+		jfs_commit_thread_waking = 1;
+		wake_up(&jfs_commit_thread_wait);
+	}
+	LAZY_UNLOCK(flags);
+}
+
+static void LogSyncRelease(struct metapage * mp)
+{
+	struct jfs_log *log = mp->log;
+
+	assert(mp->nohomeok);
+	assert(log);
+	metapage_homeok(mp);
+}
+
+/*
+ *	txQuiesce
+ *
+ *	Block all new transactions and push anonymous transactions to
+ *	completion
+ *
+ *	This does almost the same thing as jfs_sync below.  We don't
+ *	worry about deadlocking when jfs_tlocks_low is set, since we would
+ *	expect jfs_sync to get us out of that jam.
+ */
+void txQuiesce(struct super_block *sb)
+{
+	struct inode *ip;
+	struct jfs_inode_info *jfs_ip;
+	struct jfs_log *log = JFS_SBI(sb)->log;
+	tid_t tid;
+
+	set_bit(log_QUIESCE, &log->flag);
+
+	TXN_LOCK();
+restart:
+	while (!list_empty(&TxAnchor.anon_list)) {
+		jfs_ip = list_entry(TxAnchor.anon_list.next,
+				    struct jfs_inode_info,
+				    anon_inode_list);
+		ip = &jfs_ip->vfs_inode;
+
+		/*
+		 * inode will be removed from anonymous list
+		 * when it is committed
+		 */
+		TXN_UNLOCK();
+		tid = txBegin(ip->i_sb, COMMIT_INODE | COMMIT_FORCE);
+		mutex_lock(&jfs_ip->commit_mutex);
+		txCommit(tid, 1, &ip, 0);
+		txEnd(tid);
+		mutex_unlock(&jfs_ip->commit_mutex);
+		/*
+		 * Just to be safe.  I don't know how
+		 * long we can run without blocking
+		 */
+		cond_resched();
+		TXN_LOCK();
+	}
+
+	/*
+	 * If jfs_sync is running in parallel, there could be some inodes
+	 * on anon_list2.  Let's check.
+	 */
+	if (!list_empty(&TxAnchor.anon_list2)) {
+		list_splice_init(&TxAnchor.anon_list2, &TxAnchor.anon_list);
+		goto restart;
+	}
+	TXN_UNLOCK();
+
+	/*
+	 * We may need to kick off the group commit
+	 */
+	jfs_flush_journal(log, 0);
+}
+
+/*
+ * txResume()
+ *
+ * Allows transactions to start again following txQuiesce
+ */
+void txResume(struct super_block *sb)
+{
+	struct jfs_log *log = JFS_SBI(sb)->log;
+
+	clear_bit(log_QUIESCE, &log->flag);
+	TXN_WAKEUP(&log->syncwait);
+}
+
+/*
+ *	jfs_sync(void)
+ *
+ *	To be run as a kernel daemon.  This is awakened when tlocks run low.
+ *	We write any inodes that have anonymous tlocks so they will become
+ *	available.
+ */
+int jfs_sync(void *arg)
+{
+	struct inode *ip;
+	struct jfs_inode_info *jfs_ip;
+	tid_t tid;
+
+	do {
+		/*
+		 * write each inode on the anonymous inode list
+		 */
+		TXN_LOCK();
+		while (jfs_tlocks_low && !list_empty(&TxAnchor.anon_list)) {
+			jfs_ip = list_entry(TxAnchor.anon_list.next,
+					    struct jfs_inode_info,
+					    anon_inode_list);
+			ip = &jfs_ip->vfs_inode;
+
+			if (! igrab(ip)) {
+				/*
+				 * Inode is being freed
+				 */
+				list_del_init(&jfs_ip->anon_inode_list);
+			} else if (mutex_trylock(&jfs_ip->commit_mutex)) {
+				/*
+				 * inode will be removed from anonymous list
+				 * when it is committed
+				 */
+				TXN_UNLOCK();
+				tid = txBegin(ip->i_sb, COMMIT_INODE);
+				txCommit(tid, 1, &ip, 0);
+				txEnd(tid);
+				mutex_unlock(&jfs_ip->commit_mutex);
+
+				iput(ip);
+				/*
+				 * Just to be safe.  I don't know how
+				 * long we can run without blocking
+				 */
+				cond_resched();
+				TXN_LOCK();
+			} else {
+				/* We can't get the commit mutex.  It may
+				 * be held by a thread waiting for tlock's
+				 * so let's not block here.  Save it to
+				 * put back on the anon_list.
+				 */
+
+				/* Move from anon_list to anon_list2 */
+				list_move(&jfs_ip->anon_inode_list,
+					  &TxAnchor.anon_list2);
+
+				TXN_UNLOCK();
+				iput(ip);
+				TXN_LOCK();
+			}
+		}
+		/* Add anon_list2 back to anon_list */
+		list_splice_init(&TxAnchor.anon_list2, &TxAnchor.anon_list);
+
+		if (freezing(current)) {
+			TXN_UNLOCK();
+			try_to_freeze();
+		} else {
+			set_current_state(TASK_INTERRUPTIBLE);
+			TXN_UNLOCK();
+			schedule();
+		}
+	} while (!kthread_should_stop());
+
+	jfs_info("jfs_sync being killed");
+	return 0;
+}
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_JFS_DEBUG)
+int jfs_txanchor_proc_show(struct seq_file *m, void *v)
+{
+	char *freewait;
+	char *freelockwait;
+	char *lowlockwait;
+
+	freewait =
+	    waitqueue_active(&TxAnchor.freewait) ? "active" : "empty";
+	freelockwait =
+	    waitqueue_active(&TxAnchor.freelockwait) ? "active" : "empty";
+	lowlockwait =
+	    waitqueue_active(&TxAnchor.lowlockwait) ? "active" : "empty";
+
+	seq_printf(m,
+		       "JFS TxAnchor\n"
+		       "============\n"
+		       "freetid = %d\n"
+		       "freewait = %s\n"
+		       "freelock = %d\n"
+		       "freelockwait = %s\n"
+		       "lowlockwait = %s\n"
+		       "tlocksInUse = %d\n"
+		       "jfs_tlocks_low = %d\n"
+		       "unlock_queue is %sempty\n",
+		       TxAnchor.freetid,
+		       freewait,
+		       TxAnchor.freelock,
+		       freelockwait,
+		       lowlockwait,
+		       TxAnchor.tlocksInUse,
+		       jfs_tlocks_low,
+		       list_empty(&TxAnchor.unlock_queue) ? "" : "not ");
+	return 0;
+}
+#endif
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_JFS_STATISTICS)
+int jfs_txstats_proc_show(struct seq_file *m, void *v)
+{
+	seq_printf(m,
+		       "JFS TxStats\n"
+		       "===========\n"
+		       "calls to txBegin = %d\n"
+		       "txBegin blocked by sync barrier = %d\n"
+		       "txBegin blocked by tlocks low = %d\n"
+		       "txBegin blocked by no free tid = %d\n"
+		       "calls to txBeginAnon = %d\n"
+		       "txBeginAnon blocked by sync barrier = %d\n"
+		       "txBeginAnon blocked by tlocks low = %d\n"
+		       "calls to txLockAlloc = %d\n"
+		       "tLockAlloc blocked by no free lock = %d\n",
+		       TxStat.txBegin,
+		       TxStat.txBegin_barrier,
+		       TxStat.txBegin_lockslow,
+		       TxStat.txBegin_freetid,
+		       TxStat.txBeginAnon,
+		       TxStat.txBeginAnon_barrier,
+		       TxStat.txBeginAnon_lockslow,
+		       TxStat.txLockAlloc,
+		       TxStat.txLockAlloc_freelock);
+	return 0;
+}
+#endif
diff --git a/fs/jfs/jfs_txnmgr.h b/fs/jfs/jfs_txnmgr.h
new file mode 100644
index 000000000..ba71eb5ce
--- /dev/null
+++ b/fs/jfs/jfs_txnmgr.h
@@ -0,0 +1,298 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+#ifndef _H_JFS_TXNMGR
+#define _H_JFS_TXNMGR
+
+#include "jfs_logmgr.h"
+
+/*
+ * Hide implementation of TxBlock and TxLock
+ */
+#define tid_to_tblock(tid) (&TxBlock[tid])
+
+#define lid_to_tlock(lid) (&TxLock[lid])
+
+/*
+ *	transaction block
+ */
+struct tblock {
+	/*
+	 * tblock and jbuf_t common area: struct logsyncblk
+	 *
+	 * the following 5 fields are the same as struct logsyncblk
+	 * which is common to tblock and jbuf to form logsynclist
+	 */
+	u16 xflag;		/* tx commit type */
+	u16 flag;		/* tx commit state */
+	lid_t dummy;		/* Must keep structures common */
+	s32 lsn;		/* recovery lsn */
+	struct list_head synclist;	/* logsynclist link */
+
+	/* lock management */
+	struct super_block *sb;	/* super block */
+	lid_t next;		/* index of first tlock of tid */
+	lid_t last;		/* index of last tlock of tid */
+	wait_queue_head_t waitor;	/* tids waiting on this tid */
+
+	/* log management */
+	u32 logtid;		/* log transaction id */
+
+	/* commit management */
+	struct list_head cqueue;	/* commit queue list */
+	s32 clsn;		/* commit lsn */
+	struct lbuf *bp;
+	s32 pn;			/* commit record log page number */
+	s32 eor;		/* commit record eor */
+	wait_queue_head_t gcwait;	/* group commit event list:
+					 * ready transactions wait on this
+					 * event for group commit completion.
+					 */
+	union {
+		struct inode *ip; /* inode being deleted */
+		pxd_t ixpxd;	/* pxd of inode extent for created inode */
+	} u;
+	u32 ino;		/* inode number being created */
+};
+
+extern struct tblock *TxBlock;	/* transaction block table */
+
+/* commit flags: tblk->xflag */
+#define	COMMIT_SYNC	0x0001	/* synchronous commit */
+#define	COMMIT_FORCE	0x0002	/* force pageout at end of commit */
+#define	COMMIT_FLUSH	0x0004	/* init flush at end of commit */
+#define COMMIT_MAP	0x00f0
+#define	COMMIT_PMAP	0x0010	/* update pmap */
+#define	COMMIT_WMAP	0x0020	/* update wmap */
+#define	COMMIT_PWMAP	0x0040	/* update pwmap */
+#define	COMMIT_FREE	0x0f00
+#define	COMMIT_DELETE	0x0100	/* inode delete */
+#define	COMMIT_TRUNCATE	0x0200	/* file truncation */
+#define	COMMIT_CREATE	0x0400	/* inode create */
+#define	COMMIT_LAZY	0x0800	/* lazy commit */
+#define COMMIT_PAGE	0x1000	/* Identifies element as metapage */
+#define COMMIT_INODE	0x2000	/* Identifies element as inode */
+
+/* group commit flags tblk->flag: see jfs_logmgr.h */
+
+/*
+ *	transaction lock
+ */
+struct tlock {
+	lid_t next;		/* 2: index next lockword on tid locklist
+				 *	    next lockword on freelist
+				 */
+	tid_t tid;		/* 2: transaction id holding lock */
+
+	u16 flag;		/* 2: lock control */
+	u16 type;		/* 2: log type */
+
+	struct metapage *mp;	/* 4/8: object page buffer locked */
+	struct inode *ip;	/* 4/8: object */
+	/* (16) */
+
+	s16 lock[24];		/* 48: overlay area */
+};				/* (64) */
+
+extern struct tlock *TxLock;	/* transaction lock table */
+
+/*
+ * tlock flag
+ */
+/* txLock state */
+#define tlckPAGELOCK		0x8000
+#define tlckINODELOCK		0x4000
+#define tlckLINELOCK		0x2000
+#define tlckINLINELOCK		0x1000
+/* lmLog state */
+#define tlckLOG			0x0800
+/* updateMap state */
+#define	tlckUPDATEMAP		0x0080
+#define	tlckDIRECTORY		0x0040
+/* freeLock state */
+#define tlckFREELOCK		0x0008
+#define tlckWRITEPAGE		0x0004
+#define tlckFREEPAGE		0x0002
+
+/*
+ * tlock type
+ */
+#define	tlckTYPE		0xfe00
+#define	tlckINODE		0x8000
+#define	tlckXTREE		0x4000
+#define	tlckDTREE		0x2000
+#define	tlckMAP			0x1000
+#define	tlckEA			0x0800
+#define	tlckACL			0x0400
+#define	tlckDATA		0x0200
+#define	tlckBTROOT		0x0100
+
+#define	tlckOPERATION		0x00ff
+#define tlckGROW		0x0001	/* file grow */
+#define tlckREMOVE		0x0002	/* file delete */
+#define tlckTRUNCATE		0x0004	/* file truncate */
+#define tlckRELOCATE		0x0008	/* file/directory relocate */
+#define tlckENTRY		0x0001	/* directory insert/delete */
+#define tlckEXTEND		0x0002	/* directory extend in-line */
+#define tlckSPLIT		0x0010	/* splited page */
+#define tlckNEW			0x0020	/* new page from split */
+#define tlckFREE		0x0040	/* free page */
+#define tlckRELINK		0x0080	/* update sibling pointer */
+
+/*
+ *	linelock for lmLog()
+ *
+ * note: linelock and its variations are overlaid
+ * at tlock.lock: watch for alignment;
+ */
+struct lv {
+	u8 offset;		/* 1: */
+	u8 length;		/* 1: */
+};				/* (2) */
+
+#define	TLOCKSHORT	20
+#define	TLOCKLONG	28
+
+struct linelock {
+	lid_t next;		/* 2: next linelock */
+
+	s8 maxcnt;		/* 1: */
+	s8 index;		/* 1: */
+
+	u16 flag;		/* 2: */
+	u8 type;		/* 1: */
+	u8 l2linesize;		/* 1: log2 of linesize */
+	/* (8) */
+
+	struct lv lv[20];	/* 40: */
+};				/* (48) */
+
+#define dt_lock	linelock
+
+struct xtlock {
+	lid_t next;		/* 2: */
+
+	s8 maxcnt;		/* 1: */
+	s8 index;		/* 1: */
+
+	u16 flag;		/* 2: */
+	u8 type;		/* 1: */
+	u8 l2linesize;		/* 1: log2 of linesize */
+				/* (8) */
+
+	struct lv header;	/* 2: */
+	struct lv lwm;		/* 2: low water mark */
+	struct lv hwm;		/* 2: high water mark */
+	struct lv twm;		/* 2: */
+				/* (16) */
+
+	s32 pxdlock[8];		/* 32: */
+};				/* (48) */
+
+
+/*
+ *	maplock for txUpdateMap()
+ *
+ * note: maplock and its variations are overlaid
+ * at tlock.lock/linelock: watch for alignment;
+ * N.B. next field may be set by linelock, and should not
+ * be modified by maplock;
+ * N.B. index of the first pxdlock specifies index of next
+ * free maplock (i.e., number of maplock) in the tlock;
+ */
+struct maplock {
+	lid_t next;		/* 2: */
+
+	u8 maxcnt;		/* 2: */
+	u8 index;		/* 2: next free maplock index */
+
+	u16 flag;		/* 2: */
+	u8 type;		/* 1: */
+	u8 count;		/* 1: number of pxd/xad */
+				/* (8) */
+
+	pxd_t pxd;		/* 8: */
+};				/* (16): */
+
+/* maplock flag */
+#define	mlckALLOC		0x00f0
+#define	mlckALLOCXADLIST	0x0080
+#define	mlckALLOCPXDLIST	0x0040
+#define	mlckALLOCXAD		0x0020
+#define	mlckALLOCPXD		0x0010
+#define	mlckFREE		0x000f
+#define	mlckFREEXADLIST		0x0008
+#define	mlckFREEPXDLIST		0x0004
+#define	mlckFREEXAD		0x0002
+#define	mlckFREEPXD		0x0001
+
+#define	pxd_lock	maplock
+
+struct xdlistlock {
+	lid_t next;		/* 2: */
+
+	u8 maxcnt;		/* 2: */
+	u8 index;		/* 2: */
+
+	u16 flag;		/* 2: */
+	u8 type;		/* 1: */
+	u8 count;		/* 1: number of pxd/xad */
+				/* (8) */
+
+	/*
+	 * We need xdlist to be 64 bits (8 bytes), regardless of
+	 * whether void * is 32 or 64 bits
+	 */
+	union {
+		void *_xdlist;	/* pxd/xad list */
+		s64 pad;	/* 8: Force 64-bit xdlist size */
+	} union64;
+};				/* (16): */
+
+#define xdlist union64._xdlist
+
+/*
+ *	commit
+ *
+ * parameter to the commit manager routines
+ */
+struct commit {
+	tid_t tid;		/* tid = index of tblock */
+	int flag;		/* flags */
+	struct jfs_log *log;	/* log */
+	struct super_block *sb;	/* superblock */
+
+	int nip;		/* number of entries in iplist */
+	struct inode **iplist;	/* list of pointers to inodes */
+
+	/* log record descriptor on 64-bit boundary */
+	struct lrd lrd;		/* : log record descriptor */
+};
+
+/*
+ * external declarations
+ */
+extern int jfs_tlocks_low;
+
+extern int txInit(void);
+extern void txExit(void);
+extern struct tlock *txLock(tid_t, struct inode *, struct metapage *, int);
+extern struct tlock *txMaplock(tid_t, struct inode *, int);
+extern int txCommit(tid_t, int, struct inode **, int);
+extern tid_t txBegin(struct super_block *, int);
+extern void txBeginAnon(struct super_block *);
+extern void txEnd(tid_t);
+extern void txAbort(tid_t, int);
+extern struct linelock *txLinelock(struct linelock *);
+extern void txFreeMap(struct inode *, struct maplock *, struct tblock *, int);
+extern void txEA(tid_t, struct inode *, dxd_t *, dxd_t *);
+extern void txFreelock(struct inode *);
+extern int lmLog(struct jfs_log *, struct tblock *, struct lrd *,
+		 struct tlock *);
+extern void txQuiesce(struct super_block *);
+extern void txResume(struct super_block *);
+extern void txLazyUnlock(struct tblock *);
+extern int jfs_lazycommit(void *);
+extern int jfs_sync(void *);
+#endif				/* _H_JFS_TXNMGR */
diff --git a/fs/jfs/jfs_types.h b/fs/jfs/jfs_types.h
new file mode 100644
index 000000000..3ff9f26bc
--- /dev/null
+++ b/fs/jfs/jfs_types.h
@@ -0,0 +1,157 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+#ifndef _H_JFS_TYPES
+#define	_H_JFS_TYPES
+
+/*
+ *	jfs_types.h:
+ *
+ * basic type/utility definitions
+ *
+ * note: this header file must be the 1st include file
+ * of JFS include list in all JFS .c file.
+ */
+
+#include <linux/types.h>
+#include <linux/nls.h>
+
+/*
+ * transaction and lock id's
+ *
+ * Don't change these without carefully considering the impact on the
+ * size and alignment of all of the linelock variants
+ */
+typedef u16 tid_t;
+typedef u16 lid_t;
+
+/*
+ * Almost identical to Linux's timespec, but not quite
+ */
+struct timestruc_t {
+	__le32 tv_sec;
+	__le32 tv_nsec;
+};
+
+/*
+ *	handy
+ */
+
+#define LEFTMOSTONE	0x80000000
+#define	HIGHORDER	0x80000000u	/* high order bit on	*/
+#define	ONES		0xffffffffu	/* all bit on		*/
+
+/*
+ *	physical xd (pxd)
+ *
+ *	The leftmost 24 bits of len_addr are the extent length.
+ *	The rightmost 8 bits of len_addr are the most signficant bits of
+ *	the extent address
+ */
+typedef struct {
+	__le32 len_addr;
+	__le32 addr2;
+} pxd_t;
+
+/* xd_t field construction */
+
+static inline void PXDlength(pxd_t *pxd, __u32 len)
+{
+	pxd->len_addr = (pxd->len_addr & cpu_to_le32(~0xffffff)) |
+			cpu_to_le32(len & 0xffffff);
+}
+
+static inline void PXDaddress(pxd_t *pxd, __u64 addr)
+{
+	pxd->len_addr = (pxd->len_addr & cpu_to_le32(0xffffff)) |
+			cpu_to_le32((addr >> 32)<<24);
+	pxd->addr2 = cpu_to_le32(addr & 0xffffffff);
+}
+
+/* xd_t field extraction */
+static inline __u32 lengthPXD(pxd_t *pxd)
+{
+	return le32_to_cpu((pxd)->len_addr) & 0xffffff;
+}
+
+static inline __u64 addressPXD(pxd_t *pxd)
+{
+	__u64 n = le32_to_cpu(pxd->len_addr) & ~0xffffff;
+	return (n << 8) + le32_to_cpu(pxd->addr2);
+}
+
+#define MAXTREEHEIGHT 8
+/* pxd list */
+struct pxdlist {
+	s16 maxnpxd;
+	s16 npxd;
+	pxd_t pxd[MAXTREEHEIGHT];
+};
+
+
+/*
+ *	data extent descriptor (dxd)
+ */
+typedef struct {
+	__u8 flag;	/* 1: flags */
+	__u8 rsrvd[3];
+	__le32 size;		/* 4: size in byte */
+	pxd_t loc;		/* 8: address and length in unit of fsblksize */
+} dxd_t;			/* - 16 - */
+
+/* dxd_t flags */
+#define	DXD_INDEX	0x80	/* B+-tree index */
+#define	DXD_INLINE	0x40	/* in-line data extent */
+#define	DXD_EXTENT	0x20	/* out-of-line single extent */
+#define	DXD_FILE	0x10	/* out-of-line file (inode) */
+#define DXD_CORRUPT	0x08	/* Inconsistency detected */
+
+/* dxd_t field construction
+ */
+#define	DXDlength(dxd, len)	PXDlength(&(dxd)->loc, len)
+#define	DXDaddress(dxd, addr)	PXDaddress(&(dxd)->loc, addr)
+#define	lengthDXD(dxd)	lengthPXD(&(dxd)->loc)
+#define	addressDXD(dxd)	addressPXD(&(dxd)->loc)
+#define DXDsize(dxd, size32) ((dxd)->size = cpu_to_le32(size32))
+#define sizeDXD(dxd)	le32_to_cpu((dxd)->size)
+
+/*
+ *	directory entry argument
+ */
+struct component_name {
+	int namlen;
+	wchar_t *name;
+};
+
+
+/*
+ *	DASD limit information - stored in directory inode
+ */
+struct dasd {
+	u8 thresh;		/* Alert Threshold (in percent)		*/
+	u8 delta;		/* Alert Threshold delta (in percent)	*/
+	u8 rsrvd1;
+	u8 limit_hi;		/* DASD limit (in logical blocks)	*/
+	__le32 limit_lo;	/* DASD limit (in logical blocks)	*/
+	u8 rsrvd2[3];
+	u8 used_hi;		/* DASD usage (in logical blocks)	*/
+	__le32 used_lo;		/* DASD usage (in logical blocks)	*/
+};
+
+#define DASDLIMIT(dasdp) \
+	(((u64)((dasdp)->limit_hi) << 32) + __le32_to_cpu((dasdp)->limit_lo))
+#define setDASDLIMIT(dasdp, limit)\
+{\
+	(dasdp)->limit_hi = ((u64)limit) >> 32;\
+	(dasdp)->limit_lo = __cpu_to_le32(limit);\
+}
+#define DASDUSED(dasdp) \
+	(((u64)((dasdp)->used_hi) << 32) + __le32_to_cpu((dasdp)->used_lo))
+#define setDASDUSED(dasdp, used)\
+{\
+	(dasdp)->used_hi = ((u64)used) >> 32;\
+	(dasdp)->used_lo = __cpu_to_le32(used);\
+}
+
+#endif				/* !_H_JFS_TYPES */
diff --git a/fs/jfs/jfs_umount.c b/fs/jfs/jfs_umount.c
new file mode 100644
index 000000000..3e8b13e6a
--- /dev/null
+++ b/fs/jfs/jfs_umount.c
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+
+/*
+ *	jfs_umount.c
+ *
+ * note: file system in transition to aggregate/fileset:
+ * (ref. jfs_mount.c)
+ *
+ * file system unmount is interpreted as mount of the single/only
+ * fileset in the aggregate and, if unmount of the last fileset,
+ * as unmount of the aggerate;
+ */
+
+#include <linux/fs.h>
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_superblock.h"
+#include "jfs_dmap.h"
+#include "jfs_imap.h"
+#include "jfs_metapage.h"
+#include "jfs_debug.h"
+
+/*
+ * NAME:	jfs_umount(vfsp, flags, crp)
+ *
+ * FUNCTION:	vfs_umount()
+ *
+ * PARAMETERS:	vfsp	- virtual file system pointer
+ *		flags	- unmount for shutdown
+ *		crp	- credential
+ *
+ * RETURN :	EBUSY	- device has open files
+ */
+int jfs_umount(struct super_block *sb)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct inode *ipbmap = sbi->ipbmap;
+	struct inode *ipimap = sbi->ipimap;
+	struct inode *ipaimap = sbi->ipaimap;
+	struct inode *ipaimap2 = sbi->ipaimap2;
+	struct jfs_log *log;
+	int rc = 0;
+
+	jfs_info("UnMount JFS: sb:0x%p", sb);
+
+	/*
+	 *	update superblock and close log
+	 *
+	 * if mounted read-write and log based recovery was enabled
+	 */
+	if ((log = sbi->log))
+		/*
+		 * Wait for outstanding transactions to be written to log:
+		 */
+		jfs_flush_journal(log, 2);
+
+	/*
+	 * close fileset inode allocation map (aka fileset inode)
+	 */
+	diUnmount(ipimap, 0);
+
+	diFreeSpecial(ipimap);
+	sbi->ipimap = NULL;
+
+	/*
+	 * close secondary aggregate inode allocation map
+	 */
+	ipaimap2 = sbi->ipaimap2;
+	if (ipaimap2) {
+		diUnmount(ipaimap2, 0);
+		diFreeSpecial(ipaimap2);
+		sbi->ipaimap2 = NULL;
+	}
+
+	/*
+	 * close aggregate inode allocation map
+	 */
+	ipaimap = sbi->ipaimap;
+	diUnmount(ipaimap, 0);
+	diFreeSpecial(ipaimap);
+	sbi->ipaimap = NULL;
+
+	/*
+	 * close aggregate block allocation map
+	 */
+	dbUnmount(ipbmap, 0);
+
+	diFreeSpecial(ipbmap);
+	sbi->ipimap = NULL;
+
+	/*
+	 * Make sure all metadata makes it to disk before we mark
+	 * the superblock as clean
+	 */
+	filemap_write_and_wait(sbi->direct_inode->i_mapping);
+
+	/*
+	 * ensure all file system file pages are propagated to their
+	 * home blocks on disk (and their in-memory buffer pages are
+	 * invalidated) BEFORE updating file system superblock state
+	 * (to signify file system is unmounted cleanly, and thus in
+	 * consistent state) and log superblock active file system
+	 * list (to signify skip logredo()).
+	 */
+	if (log) {		/* log = NULL if read-only mount */
+		updateSuper(sb, FM_CLEAN);
+
+		/*
+		 * close log:
+		 *
+		 * remove file system from log active file system list.
+		 */
+		rc = lmLogClose(sb);
+	}
+	jfs_info("UnMount JFS Complete: rc = %d", rc);
+	return rc;
+}
+
+
+int jfs_umount_rw(struct super_block *sb)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct jfs_log *log = sbi->log;
+
+	if (!log)
+		return 0;
+
+	/*
+	 * close log:
+	 *
+	 * remove file system from log active file system list.
+	 */
+	jfs_flush_journal(log, 2);
+
+	/*
+	 * Make sure all metadata makes it to disk
+	 */
+	dbSync(sbi->ipbmap);
+	diSync(sbi->ipimap);
+
+	/*
+	 * Note that we have to do this even if sync_blockdev() will
+	 * do exactly the same a few instructions later:  We can't
+	 * mark the superblock clean before everything is flushed to
+	 * disk.
+	 */
+	filemap_write_and_wait(sbi->direct_inode->i_mapping);
+
+	updateSuper(sb, FM_CLEAN);
+
+	return lmLogClose(sb);
+}
diff --git a/fs/jfs/jfs_unicode.c b/fs/jfs/jfs_unicode.c
new file mode 100644
index 000000000..0c1e90272
--- /dev/null
+++ b/fs/jfs/jfs_unicode.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ */
+
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_unicode.h"
+#include "jfs_debug.h"
+
+/*
+ * NAME:	jfs_strfromUCS()
+ *
+ * FUNCTION:	Convert little-endian unicode string to character string
+ *
+ */
+int jfs_strfromUCS_le(char *to, const __le16 * from,
+		      int len, struct nls_table *codepage)
+{
+	int i;
+	int outlen = 0;
+	static int warn_again = 5;	/* Only warn up to 5 times total */
+	int warn = !!warn_again;	/* once per string */
+
+	if (codepage) {
+		for (i = 0; (i < len) && from[i]; i++) {
+			int charlen;
+			charlen =
+			    codepage->uni2char(le16_to_cpu(from[i]),
+					       &to[outlen],
+					       NLS_MAX_CHARSET_SIZE);
+			if (charlen > 0)
+				outlen += charlen;
+			else
+				to[outlen++] = '?';
+		}
+	} else {
+		for (i = 0; (i < len) && from[i]; i++) {
+			if (unlikely(le16_to_cpu(from[i]) & 0xff00)) {
+				to[i] = '?';
+				if (unlikely(warn)) {
+					warn--;
+					warn_again--;
+					printk(KERN_ERR
+			"non-latin1 character 0x%x found in JFS file name\n",
+					       le16_to_cpu(from[i]));
+					printk(KERN_ERR
+				"mount with iocharset=utf8 to access\n");
+				}
+
+			}
+			else
+				to[i] = (char) (le16_to_cpu(from[i]));
+		}
+		outlen = i;
+	}
+	to[outlen] = 0;
+	return outlen;
+}
+
+/*
+ * NAME:	jfs_strtoUCS()
+ *
+ * FUNCTION:	Convert character string to unicode string
+ *
+ */
+static int jfs_strtoUCS(wchar_t * to, const unsigned char *from, int len,
+		struct nls_table *codepage)
+{
+	int charlen;
+	int i;
+
+	if (codepage) {
+		for (i = 0; len && *from; i++, from += charlen, len -= charlen)
+		{
+			charlen = codepage->char2uni(from, len, &to[i]);
+			if (charlen < 1) {
+				jfs_err("jfs_strtoUCS: char2uni returned %d.",
+					charlen);
+				jfs_err("charset = %s, char = 0x%x",
+					codepage->charset, *from);
+				return charlen;
+			}
+		}
+	} else {
+		for (i = 0; (i < len) && from[i]; i++)
+			to[i] = (wchar_t) from[i];
+	}
+
+	to[i] = 0;
+	return i;
+}
+
+/*
+ * NAME:	get_UCSname()
+ *
+ * FUNCTION:	Allocate and translate to unicode string
+ *
+ */
+int get_UCSname(struct component_name * uniName, struct dentry *dentry)
+{
+	struct nls_table *nls_tab = JFS_SBI(dentry->d_sb)->nls_tab;
+	int length = dentry->d_name.len;
+
+	if (length > JFS_NAME_MAX)
+		return -ENAMETOOLONG;
+
+	uniName->name =
+	    kmalloc_array(length + 1, sizeof(wchar_t), GFP_NOFS);
+
+	if (uniName->name == NULL)
+		return -ENOMEM;
+
+	uniName->namlen = jfs_strtoUCS(uniName->name, dentry->d_name.name,
+				       length, nls_tab);
+
+	if (uniName->namlen < 0) {
+		kfree(uniName->name);
+		return uniName->namlen;
+	}
+
+	return 0;
+}
diff --git a/fs/jfs/jfs_unicode.h b/fs/jfs/jfs_unicode.h
new file mode 100644
index 000000000..9db62d047
--- /dev/null
+++ b/fs/jfs/jfs_unicode.h
@@ -0,0 +1,143 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+#ifndef _H_JFS_UNICODE
+#define _H_JFS_UNICODE
+
+#include <linux/slab.h>
+#include <asm/byteorder.h>
+#include "jfs_types.h"
+
+typedef struct {
+	wchar_t start;
+	wchar_t end;
+	signed char *table;
+} UNICASERANGE;
+
+extern signed char UniUpperTable[512];
+extern UNICASERANGE UniUpperRange[];
+extern int get_UCSname(struct component_name *, struct dentry *);
+extern int jfs_strfromUCS_le(char *, const __le16 *, int, struct nls_table *);
+
+#define free_UCSname(COMP) kfree((COMP)->name)
+
+/*
+ * UniStrcpy:  Copy a string
+ */
+static inline wchar_t *UniStrcpy(wchar_t * ucs1, const wchar_t * ucs2)
+{
+	wchar_t *anchor = ucs1;	/* save the start of result string */
+
+	while ((*ucs1++ = *ucs2++));
+	return anchor;
+}
+
+
+
+/*
+ * UniStrncpy:  Copy length limited string with pad
+ */
+static inline __le16 *UniStrncpy_le(__le16 * ucs1, const __le16 * ucs2,
+				  size_t n)
+{
+	__le16 *anchor = ucs1;
+
+	while (n-- && *ucs2)	/* Copy the strings */
+		*ucs1++ = *ucs2++;
+
+	n++;
+	while (n--)		/* Pad with nulls */
+		*ucs1++ = 0;
+	return anchor;
+}
+
+/*
+ * UniStrncmp_le:  Compare length limited string - native to little-endian
+ */
+static inline int UniStrncmp_le(const wchar_t * ucs1, const __le16 * ucs2,
+				size_t n)
+{
+	if (!n)
+		return 0;	/* Null strings are equal */
+	while ((*ucs1 == __le16_to_cpu(*ucs2)) && *ucs1 && --n) {
+		ucs1++;
+		ucs2++;
+	}
+	return (int) *ucs1 - (int) __le16_to_cpu(*ucs2);
+}
+
+/*
+ * UniStrncpy_to_le:  Copy length limited string with pad to little-endian
+ */
+static inline __le16 *UniStrncpy_to_le(__le16 * ucs1, const wchar_t * ucs2,
+				       size_t n)
+{
+	__le16 *anchor = ucs1;
+
+	while (n-- && *ucs2)	/* Copy the strings */
+		*ucs1++ = cpu_to_le16(*ucs2++);
+
+	n++;
+	while (n--)		/* Pad with nulls */
+		*ucs1++ = 0;
+	return anchor;
+}
+
+/*
+ * UniStrncpy_from_le:  Copy length limited string with pad from little-endian
+ */
+static inline wchar_t *UniStrncpy_from_le(wchar_t * ucs1, const __le16 * ucs2,
+					  size_t n)
+{
+	wchar_t *anchor = ucs1;
+
+	while (n-- && *ucs2)	/* Copy the strings */
+		*ucs1++ = __le16_to_cpu(*ucs2++);
+
+	n++;
+	while (n--)		/* Pad with nulls */
+		*ucs1++ = 0;
+	return anchor;
+}
+
+/*
+ * UniToupper:  Convert a unicode character to upper case
+ */
+static inline wchar_t UniToupper(wchar_t uc)
+{
+	UNICASERANGE *rp;
+
+	if (uc < sizeof(UniUpperTable)) {	/* Latin characters */
+		return uc + UniUpperTable[uc];	/* Use base tables */
+	} else {
+		rp = UniUpperRange;	/* Use range tables */
+		while (rp->start) {
+			if (uc < rp->start)	/* Before start of range */
+				return uc;	/* Uppercase = input */
+			if (uc <= rp->end)	/* In range */
+				return uc + rp->table[uc - rp->start];
+			rp++;	/* Try next range */
+		}
+	}
+	return uc;		/* Past last range */
+}
+
+
+/*
+ * UniStrupr:  Upper case a unicode string
+ */
+static inline wchar_t *UniStrupr(wchar_t * upin)
+{
+	wchar_t *up;
+
+	up = upin;
+	while (*up) {		/* For all characters */
+		*up = UniToupper(*up);
+		up++;
+	}
+	return upin;		/* Return input pointer */
+}
+
+#endif				/* !_H_JFS_UNICODE */
diff --git a/fs/jfs/jfs_uniupr.c b/fs/jfs/jfs_uniupr.c
new file mode 100644
index 000000000..d0b18c7be
--- /dev/null
+++ b/fs/jfs/jfs_uniupr.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ */
+
+#include <linux/fs.h>
+#include "jfs_unicode.h"
+
+/*
+ * Latin upper case
+ */
+signed char UniUpperTable[512] = {
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 000-00f */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 010-01f */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 020-02f */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 030-03f */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 040-04f */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 050-05f */
+   0,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32, /* 060-06f */
+ -32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,  0,  0,  0,  0,  0, /* 070-07f */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 080-08f */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 090-09f */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 0a0-0af */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 0b0-0bf */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 0c0-0cf */
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 0d0-0df */
+ -32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32, /* 0e0-0ef */
+ -32,-32,-32,-32,-32,-32,-32,  0,-32,-32,-32,-32,-32,-32,-32,121, /* 0f0-0ff */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 100-10f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 110-11f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 120-12f */
+   0,  0,  0, -1,  0, -1,  0, -1,  0,  0, -1,  0, -1,  0, -1,  0, /* 130-13f */
+  -1,  0, -1,  0, -1,  0, -1,  0, -1,  0,  0, -1,  0, -1,  0, -1, /* 140-14f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 150-15f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 160-16f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0,  0, -1,  0, -1,  0, -1,  0, /* 170-17f */
+   0,  0,  0, -1,  0, -1,  0,  0, -1,  0,  0,  0, -1,  0,  0,  0, /* 180-18f */
+   0,  0, -1,  0,  0,  0,  0,  0,  0, -1,  0,  0,  0,  0,  0,  0, /* 190-19f */
+   0, -1,  0, -1,  0, -1,  0,  0, -1,  0,  0,  0,  0, -1,  0,  0, /* 1a0-1af */
+  -1,  0,  0,  0, -1,  0, -1,  0,  0, -1,  0,  0,  0, -1,  0,  0, /* 1b0-1bf */
+   0,  0,  0,  0,  0, -1, -2,  0, -1, -2,  0, -1, -2,  0, -1,  0, /* 1c0-1cf */
+  -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,-79,  0, -1, /* 1d0-1df */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e0-1ef */
+   0,  0, -1, -2,  0, -1,  0,  0,  0, -1,  0, -1,  0, -1,  0, -1, /* 1f0-1ff */
+};
+
+/* Upper case range - Greek */
+static signed char UniCaseRangeU03a0[47] = {
+   0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,-38,-37,-37,-37, /* 3a0-3af */
+   0,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32, /* 3b0-3bf */
+ -32,-32,-31,-32,-32,-32,-32,-32,-32,-32,-32,-32,-64,-63,-63,
+};
+
+/* Upper case range - Cyrillic */
+static signed char UniCaseRangeU0430[48] = {
+ -32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32, /* 430-43f */
+ -32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32, /* 440-44f */
+   0,-80,-80,-80,-80,-80,-80,-80,-80,-80,-80,-80,-80,  0,-80,-80, /* 450-45f */
+};
+
+/* Upper case range - Extended cyrillic */
+static signed char UniCaseRangeU0490[61] = {
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 490-49f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 4a0-4af */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 4b0-4bf */
+   0,  0, -1,  0, -1,  0,  0,  0, -1,  0,  0,  0, -1,
+};
+
+/* Upper case range - Extended latin and greek */
+static signed char UniCaseRangeU1e00[509] = {
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e00-1e0f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e10-1e1f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e20-1e2f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e30-1e3f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e40-1e4f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e50-1e5f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e60-1e6f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e70-1e7f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1e80-1e8f */
+   0, -1,  0, -1,  0, -1,  0,  0,  0,  0,  0,-59,  0, -1,  0, -1, /* 1e90-1e9f */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1ea0-1eaf */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1eb0-1ebf */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1ec0-1ecf */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1ed0-1edf */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0, -1, /* 1ee0-1eef */
+   0, -1,  0, -1,  0, -1,  0, -1,  0, -1,  0,  0,  0,  0,  0,  0, /* 1ef0-1eff */
+   8,  8,  8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f00-1f0f */
+   8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f10-1f1f */
+   8,  8,  8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f20-1f2f */
+   8,  8,  8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f30-1f3f */
+   8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f40-1f4f */
+   0,  8,  0,  8,  0,  8,  0,  8,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f50-1f5f */
+   8,  8,  8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f60-1f6f */
+  74, 74, 86, 86, 86, 86,100,100,  0,  0,112,112,126,126,  0,  0, /* 1f70-1f7f */
+   8,  8,  8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f80-1f8f */
+   8,  8,  8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0, /* 1f90-1f9f */
+   8,  8,  8,  8,  8,  8,  8,  8,  0,  0,  0,  0,  0,  0,  0,  0, /* 1fa0-1faf */
+   8,  8,  0,  9,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 1fb0-1fbf */
+   0,  0,  0,  9,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 1fc0-1fcf */
+   8,  8,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 1fd0-1fdf */
+   8,  8,  0,  0,  0,  7,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, /* 1fe0-1fef */
+   0,  0,  0,  9,  0,  0,  0,  0,  0,  0,  0,  0,  0,
+};
+
+/* Upper case range - Wide latin */
+static signed char UniCaseRangeUff40[27] = {
+   0,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32, /* ff40-ff4f */
+ -32,-32,-32,-32,-32,-32,-32,-32,-32,-32,-32,
+};
+
+/*
+ * Upper Case Range
+ */
+UNICASERANGE UniUpperRange[] = {
+    { 0x03a0,  0x03ce,  UniCaseRangeU03a0 },
+    { 0x0430,  0x045f,  UniCaseRangeU0430 },
+    { 0x0490,  0x04cc,  UniCaseRangeU0490 },
+    { 0x1e00,  0x1ffc,  UniCaseRangeU1e00 },
+    { 0xff40,  0xff5a,  UniCaseRangeUff40 },
+    { 0 }
+};
diff --git a/fs/jfs/jfs_xattr.h b/fs/jfs/jfs_xattr.h
new file mode 100644
index 000000000..c50167a7b
--- /dev/null
+++ b/fs/jfs/jfs_xattr.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ */
+
+#ifndef H_JFS_XATTR
+#define H_JFS_XATTR
+
+#include <linux/xattr.h>
+
+/*
+ * jfs_ea_list describe the on-disk format of the extended attributes.
+ * I know the null-terminator is redundant since namelen is stored, but
+ * I am maintaining compatibility with OS/2 where possible.
+ */
+struct jfs_ea {
+	u8 flag;	/* Unused? */
+	u8 namelen;	/* Length of name */
+	__le16 valuelen;	/* Length of value */
+	char name[];	/* Attribute name (includes null-terminator) */
+};			/* Value immediately follows name */
+
+struct jfs_ea_list {
+	__le32 size;		/* overall size */
+	struct jfs_ea ea[];	/* Variable length list */
+};
+
+/* Macros for defining maxiumum number of bytes supported for EAs */
+#define MAXEASIZE	65535
+#define MAXEALISTSIZE	MAXEASIZE
+
+/*
+ * some macros for dealing with variable length EA lists.
+ */
+#define EA_SIZE(ea) \
+	(sizeof (struct jfs_ea) + (ea)->namelen + 1 + \
+	 le16_to_cpu((ea)->valuelen))
+#define	NEXT_EA(ea) ((struct jfs_ea *) (((char *) (ea)) + (EA_SIZE (ea))))
+#define	FIRST_EA(ealist) ((ealist)->ea)
+#define	EALIST_SIZE(ealist) le32_to_cpu((ealist)->size)
+#define	END_EALIST(ealist) \
+	((struct jfs_ea *) (((char *) (ealist)) + EALIST_SIZE(ealist)))
+
+extern int __jfs_setxattr(tid_t, struct inode *, const char *, const void *,
+			  size_t, int);
+extern ssize_t __jfs_getxattr(struct inode *, const char *, void *, size_t);
+extern ssize_t jfs_listxattr(struct dentry *, char *, size_t);
+
+extern const struct xattr_handler *jfs_xattr_handlers[];
+
+#ifdef CONFIG_JFS_SECURITY
+extern int jfs_init_security(tid_t, struct inode *, struct inode *,
+			     const struct qstr *);
+#else
+static inline int jfs_init_security(tid_t tid, struct inode *inode,
+				    struct inode *dir, const struct qstr *qstr)
+{
+	return 0;
+}
+#endif
+
+#endif	/* H_JFS_XATTR */
diff --git a/fs/jfs/jfs_xtree.c b/fs/jfs/jfs_xtree.c
new file mode 100644
index 000000000..2d304cee8
--- /dev/null
+++ b/fs/jfs/jfs_xtree.c
@@ -0,0 +1,2916 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2005
+ */
+/*
+ *	jfs_xtree.c: extent allocation descriptor B+-tree manager
+ */
+
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/quotaops.h>
+#include <linux/seq_file.h>
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_metapage.h"
+#include "jfs_dmap.h"
+#include "jfs_dinode.h"
+#include "jfs_superblock.h"
+#include "jfs_debug.h"
+
+/*
+ * xtree local flag
+ */
+#define XT_INSERT	0x00000001
+
+/*
+ *	xtree key/entry comparison: extent offset
+ *
+ * return:
+ *	-1: k < start of extent
+ *	 0: start_of_extent <= k <= end_of_extent
+ *	 1: k > end_of_extent
+ */
+#define XT_CMP(CMP, K, X, OFFSET64)\
+{\
+	OFFSET64 = offsetXAD(X);\
+	(CMP) = ((K) >= OFFSET64 + lengthXAD(X)) ? 1 :\
+		((K) < OFFSET64) ? -1 : 0;\
+}
+
+/* write a xad entry */
+#define XT_PUTENTRY(XAD, FLAG, OFF, LEN, ADDR)\
+{\
+	(XAD)->flag = (FLAG);\
+	XADoffset((XAD), (OFF));\
+	XADlength((XAD), (LEN));\
+	XADaddress((XAD), (ADDR));\
+}
+
+#define XT_PAGE(IP, MP) BT_PAGE(IP, MP, xtpage_t, i_xtroot)
+
+/* get page buffer for specified block address */
+/* ToDo: Replace this ugly macro with a function */
+#define XT_GETPAGE(IP, BN, MP, SIZE, P, RC)				\
+do {									\
+	BT_GETPAGE(IP, BN, MP, xtpage_t, SIZE, P, RC, i_xtroot);	\
+	if (!(RC)) {							\
+		if ((le16_to_cpu((P)->header.nextindex) < XTENTRYSTART) || \
+		    (le16_to_cpu((P)->header.nextindex) >		\
+		     le16_to_cpu((P)->header.maxentry)) ||		\
+		    (le16_to_cpu((P)->header.maxentry) >		\
+		     (((BN) == 0) ? XTROOTMAXSLOT : PSIZE >> L2XTSLOTSIZE))) { \
+			jfs_error((IP)->i_sb,				\
+				  "XT_GETPAGE: xtree page corrupt\n");	\
+			BT_PUTPAGE(MP);					\
+			MP = NULL;					\
+			RC = -EIO;					\
+		}							\
+	}								\
+} while (0)
+
+/* for consistency */
+#define XT_PUTPAGE(MP) BT_PUTPAGE(MP)
+
+#define XT_GETSEARCH(IP, LEAF, BN, MP, P, INDEX) \
+	BT_GETSEARCH(IP, LEAF, BN, MP, xtpage_t, P, INDEX, i_xtroot)
+/* xtree entry parameter descriptor */
+struct xtsplit {
+	struct metapage *mp;
+	s16 index;
+	u8 flag;
+	s64 off;
+	s64 addr;
+	int len;
+	struct pxdlist *pxdlist;
+};
+
+
+/*
+ *	statistics
+ */
+#ifdef CONFIG_JFS_STATISTICS
+static struct {
+	uint search;
+	uint fastSearch;
+	uint split;
+} xtStat;
+#endif
+
+
+/*
+ * forward references
+ */
+static int xtSearch(struct inode *ip, s64 xoff, s64 *next, int *cmpp,
+		    struct btstack * btstack, int flag);
+
+static int xtSplitUp(tid_t tid,
+		     struct inode *ip,
+		     struct xtsplit * split, struct btstack * btstack);
+
+static int xtSplitPage(tid_t tid, struct inode *ip, struct xtsplit * split,
+		       struct metapage ** rmpp, s64 * rbnp);
+
+static int xtSplitRoot(tid_t tid, struct inode *ip,
+		       struct xtsplit * split, struct metapage ** rmpp);
+
+/*
+ *	xtLookup()
+ *
+ * function: map a single page into a physical extent;
+ */
+int xtLookup(struct inode *ip, s64 lstart,
+	     s64 llen, int *pflag, s64 * paddr, s32 * plen, int no_check)
+{
+	int rc = 0;
+	struct btstack btstack;
+	int cmp;
+	s64 bn;
+	struct metapage *mp;
+	xtpage_t *p;
+	int index;
+	xad_t *xad;
+	s64 next, size, xoff, xend;
+	int xlen;
+	s64 xaddr;
+
+	*paddr = 0;
+	*plen = llen;
+
+	if (!no_check) {
+		/* is lookup offset beyond eof ? */
+		size = ((u64) ip->i_size + (JFS_SBI(ip->i_sb)->bsize - 1)) >>
+		    JFS_SBI(ip->i_sb)->l2bsize;
+		if (lstart >= size)
+			return 0;
+	}
+
+	/*
+	 * search for the xad entry covering the logical extent
+	 */
+//search:
+	if ((rc = xtSearch(ip, lstart, &next, &cmp, &btstack, 0))) {
+		jfs_err("xtLookup: xtSearch returned %d", rc);
+		return rc;
+	}
+
+	/*
+	 *	compute the physical extent covering logical extent
+	 *
+	 * N.B. search may have failed (e.g., hole in sparse file),
+	 * and returned the index of the next entry.
+	 */
+	/* retrieve search result */
+	XT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+	/* is xad found covering start of logical extent ?
+	 * lstart is a page start address,
+	 * i.e., lstart cannot start in a hole;
+	 */
+	if (cmp) {
+		if (next)
+			*plen = min(next - lstart, llen);
+		goto out;
+	}
+
+	/*
+	 * lxd covered by xad
+	 */
+	xad = &p->xad[index];
+	xoff = offsetXAD(xad);
+	xlen = lengthXAD(xad);
+	xend = xoff + xlen;
+	xaddr = addressXAD(xad);
+
+	/* initialize new pxd */
+	*pflag = xad->flag;
+	*paddr = xaddr + (lstart - xoff);
+	/* a page must be fully covered by an xad */
+	*plen = min(xend - lstart, llen);
+
+      out:
+	XT_PUTPAGE(mp);
+
+	return rc;
+}
+
+/*
+ *	xtSearch()
+ *
+ * function:	search for the xad entry covering specified offset.
+ *
+ * parameters:
+ *	ip	- file object;
+ *	xoff	- extent offset;
+ *	nextp	- address of next extent (if any) for search miss
+ *	cmpp	- comparison result:
+ *	btstack - traverse stack;
+ *	flag	- search process flag (XT_INSERT);
+ *
+ * returns:
+ *	btstack contains (bn, index) of search path traversed to the entry.
+ *	*cmpp is set to result of comparison with the entry returned.
+ *	the page containing the entry is pinned at exit.
+ */
+static int xtSearch(struct inode *ip, s64 xoff,	s64 *nextp,
+		    int *cmpp, struct btstack * btstack, int flag)
+{
+	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+	int rc = 0;
+	int cmp = 1;		/* init for empty page */
+	s64 bn;			/* block number */
+	struct metapage *mp;	/* page buffer */
+	xtpage_t *p;		/* page */
+	xad_t *xad;
+	int base, index, lim, btindex;
+	struct btframe *btsp;
+	int nsplit = 0;		/* number of pages to split */
+	s64 t64;
+	s64 next = 0;
+
+	INCREMENT(xtStat.search);
+
+	BT_CLR(btstack);
+
+	btstack->nsplit = 0;
+
+	/*
+	 *	search down tree from root:
+	 *
+	 * between two consecutive entries of <Ki, Pi> and <Kj, Pj> of
+	 * internal page, child page Pi contains entry with k, Ki <= K < Kj.
+	 *
+	 * if entry with search key K is not found
+	 * internal page search find the entry with largest key Ki
+	 * less than K which point to the child page to search;
+	 * leaf page search find the entry with smallest key Kj
+	 * greater than K so that the returned index is the position of
+	 * the entry to be shifted right for insertion of new entry.
+	 * for empty tree, search key is greater than any key of the tree.
+	 *
+	 * by convention, root bn = 0.
+	 */
+	for (bn = 0;;) {
+		/* get/pin the page to search */
+		XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		/* try sequential access heuristics with the previous
+		 * access entry in target leaf page:
+		 * once search narrowed down into the target leaf,
+		 * key must either match an entry in the leaf or
+		 * key entry does not exist in the tree;
+		 */
+//fastSearch:
+		if ((jfs_ip->btorder & BT_SEQUENTIAL) &&
+		    (p->header.flag & BT_LEAF) &&
+		    (index = jfs_ip->btindex) <
+		    le16_to_cpu(p->header.nextindex)) {
+			xad = &p->xad[index];
+			t64 = offsetXAD(xad);
+			if (xoff < t64 + lengthXAD(xad)) {
+				if (xoff >= t64) {
+					*cmpp = 0;
+					goto out;
+				}
+
+				/* stop sequential access heuristics */
+				goto binarySearch;
+			} else {	/* (t64 + lengthXAD(xad)) <= xoff */
+
+				/* try next sequential entry */
+				index++;
+				if (index <
+				    le16_to_cpu(p->header.nextindex)) {
+					xad++;
+					t64 = offsetXAD(xad);
+					if (xoff < t64 + lengthXAD(xad)) {
+						if (xoff >= t64) {
+							*cmpp = 0;
+							goto out;
+						}
+
+						/* miss: key falls between
+						 * previous and this entry
+						 */
+						*cmpp = 1;
+						next = t64;
+						goto out;
+					}
+
+					/* (xoff >= t64 + lengthXAD(xad));
+					 * matching entry may be further out:
+					 * stop heuristic search
+					 */
+					/* stop sequential access heuristics */
+					goto binarySearch;
+				}
+
+				/* (index == p->header.nextindex);
+				 * miss: key entry does not exist in
+				 * the target leaf/tree
+				 */
+				*cmpp = 1;
+				goto out;
+			}
+
+			/*
+			 * if hit, return index of the entry found, and
+			 * if miss, where new entry with search key is
+			 * to be inserted;
+			 */
+		      out:
+			/* compute number of pages to split */
+			if (flag & XT_INSERT) {
+				if (p->header.nextindex ==	/* little-endian */
+				    p->header.maxentry)
+					nsplit++;
+				else
+					nsplit = 0;
+				btstack->nsplit = nsplit;
+			}
+
+			/* save search result */
+			btsp = btstack->top;
+			btsp->bn = bn;
+			btsp->index = index;
+			btsp->mp = mp;
+
+			/* update sequential access heuristics */
+			jfs_ip->btindex = index;
+
+			if (nextp)
+				*nextp = next;
+
+			INCREMENT(xtStat.fastSearch);
+			return 0;
+		}
+
+		/* well, ... full search now */
+	      binarySearch:
+		lim = le16_to_cpu(p->header.nextindex) - XTENTRYSTART;
+
+		/*
+		 * binary search with search key K on the current page
+		 */
+		for (base = XTENTRYSTART; lim; lim >>= 1) {
+			index = base + (lim >> 1);
+
+			XT_CMP(cmp, xoff, &p->xad[index], t64);
+			if (cmp == 0) {
+				/*
+				 *	search hit
+				 */
+				/* search hit - leaf page:
+				 * return the entry found
+				 */
+				if (p->header.flag & BT_LEAF) {
+					*cmpp = cmp;
+
+					/* compute number of pages to split */
+					if (flag & XT_INSERT) {
+						if (p->header.nextindex ==
+						    p->header.maxentry)
+							nsplit++;
+						else
+							nsplit = 0;
+						btstack->nsplit = nsplit;
+					}
+
+					/* save search result */
+					btsp = btstack->top;
+					btsp->bn = bn;
+					btsp->index = index;
+					btsp->mp = mp;
+
+					/* init sequential access heuristics */
+					btindex = jfs_ip->btindex;
+					if (index == btindex ||
+					    index == btindex + 1)
+						jfs_ip->btorder = BT_SEQUENTIAL;
+					else
+						jfs_ip->btorder = BT_RANDOM;
+					jfs_ip->btindex = index;
+
+					return 0;
+				}
+				/* search hit - internal page:
+				 * descend/search its child page
+				 */
+				if (index < le16_to_cpu(p->header.nextindex)-1)
+					next = offsetXAD(&p->xad[index + 1]);
+				goto next;
+			}
+
+			if (cmp > 0) {
+				base = index + 1;
+				--lim;
+			}
+		}
+
+		/*
+		 *	search miss
+		 *
+		 * base is the smallest index with key (Kj) greater than
+		 * search key (K) and may be zero or maxentry index.
+		 */
+		if (base < le16_to_cpu(p->header.nextindex))
+			next = offsetXAD(&p->xad[base]);
+		/*
+		 * search miss - leaf page:
+		 *
+		 * return location of entry (base) where new entry with
+		 * search key K is to be inserted.
+		 */
+		if (p->header.flag & BT_LEAF) {
+			*cmpp = cmp;
+
+			/* compute number of pages to split */
+			if (flag & XT_INSERT) {
+				if (p->header.nextindex ==
+				    p->header.maxentry)
+					nsplit++;
+				else
+					nsplit = 0;
+				btstack->nsplit = nsplit;
+			}
+
+			/* save search result */
+			btsp = btstack->top;
+			btsp->bn = bn;
+			btsp->index = base;
+			btsp->mp = mp;
+
+			/* init sequential access heuristics */
+			btindex = jfs_ip->btindex;
+			if (base == btindex || base == btindex + 1)
+				jfs_ip->btorder = BT_SEQUENTIAL;
+			else
+				jfs_ip->btorder = BT_RANDOM;
+			jfs_ip->btindex = base;
+
+			if (nextp)
+				*nextp = next;
+
+			return 0;
+		}
+
+		/*
+		 * search miss - non-leaf page:
+		 *
+		 * if base is non-zero, decrement base by one to get the parent
+		 * entry of the child page to search.
+		 */
+		index = base ? base - 1 : base;
+
+		/*
+		 * go down to child page
+		 */
+	      next:
+		/* update number of pages to split */
+		if (p->header.nextindex == p->header.maxentry)
+			nsplit++;
+		else
+			nsplit = 0;
+
+		/* push (bn, index) of the parent page/entry */
+		if (BT_STACK_FULL(btstack)) {
+			jfs_error(ip->i_sb, "stack overrun!\n");
+			XT_PUTPAGE(mp);
+			return -EIO;
+		}
+		BT_PUSH(btstack, bn, index);
+
+		/* get the child page block number */
+		bn = addressXAD(&p->xad[index]);
+
+		/* unpin the parent page */
+		XT_PUTPAGE(mp);
+	}
+}
+
+/*
+ *	xtInsert()
+ *
+ * function:
+ *
+ * parameter:
+ *	tid	- transaction id;
+ *	ip	- file object;
+ *	xflag	- extent flag (XAD_NOTRECORDED):
+ *	xoff	- extent offset;
+ *	xlen	- extent length;
+ *	xaddrp	- extent address pointer (in/out):
+ *		if (*xaddrp)
+ *			caller allocated data extent at *xaddrp;
+ *		else
+ *			allocate data extent and return its xaddr;
+ *	flag	-
+ *
+ * return:
+ */
+int xtInsert(tid_t tid,		/* transaction id */
+	     struct inode *ip, int xflag, s64 xoff, s32 xlen, s64 * xaddrp,
+	     int flag)
+{
+	int rc = 0;
+	s64 xaddr, hint;
+	struct metapage *mp;	/* meta-page buffer */
+	xtpage_t *p;		/* base B+-tree index page */
+	s64 bn;
+	int index, nextindex;
+	struct btstack btstack;	/* traverse stack */
+	struct xtsplit split;	/* split information */
+	xad_t *xad;
+	int cmp;
+	s64 next;
+	struct tlock *tlck;
+	struct xtlock *xtlck;
+
+	jfs_info("xtInsert: nxoff:0x%lx nxlen:0x%x", (ulong) xoff, xlen);
+
+	/*
+	 *	search for the entry location at which to insert:
+	 *
+	 * xtFastSearch() and xtSearch() both returns (leaf page
+	 * pinned, index at which to insert).
+	 * n.b. xtSearch() may return index of maxentry of
+	 * the full page.
+	 */
+	if ((rc = xtSearch(ip, xoff, &next, &cmp, &btstack, XT_INSERT)))
+		return rc;
+
+	/* retrieve search result */
+	XT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+	/* This test must follow XT_GETSEARCH since mp must be valid if
+	 * we branch to out: */
+	if ((cmp == 0) || (next && (xlen > next - xoff))) {
+		rc = -EEXIST;
+		goto out;
+	}
+
+	/*
+	 * allocate data extent requested
+	 *
+	 * allocation hint: last xad
+	 */
+	if ((xaddr = *xaddrp) == 0) {
+		if (index > XTENTRYSTART) {
+			xad = &p->xad[index - 1];
+			hint = addressXAD(xad) + lengthXAD(xad) - 1;
+		} else
+			hint = 0;
+		if ((rc = dquot_alloc_block(ip, xlen)))
+			goto out;
+		if ((rc = dbAlloc(ip, hint, (s64) xlen, &xaddr))) {
+			dquot_free_block(ip, xlen);
+			goto out;
+		}
+	}
+
+	/*
+	 *	insert entry for new extent
+	 */
+	xflag |= XAD_NEW;
+
+	/*
+	 *	if the leaf page is full, split the page and
+	 *	propagate up the router entry for the new page from split
+	 *
+	 * The xtSplitUp() will insert the entry and unpin the leaf page.
+	 */
+	nextindex = le16_to_cpu(p->header.nextindex);
+	if (nextindex == le16_to_cpu(p->header.maxentry)) {
+		split.mp = mp;
+		split.index = index;
+		split.flag = xflag;
+		split.off = xoff;
+		split.len = xlen;
+		split.addr = xaddr;
+		split.pxdlist = NULL;
+		if ((rc = xtSplitUp(tid, ip, &split, &btstack))) {
+			/* undo data extent allocation */
+			if (*xaddrp == 0) {
+				dbFree(ip, xaddr, (s64) xlen);
+				dquot_free_block(ip, xlen);
+			}
+			return rc;
+		}
+
+		*xaddrp = xaddr;
+		return 0;
+	}
+
+	/*
+	 *	insert the new entry into the leaf page
+	 */
+	/*
+	 * acquire a transaction lock on the leaf page;
+	 *
+	 * action: xad insertion/extension;
+	 */
+	BT_MARK_DIRTY(mp, ip);
+
+	/* if insert into middle, shift right remaining entries. */
+	if (index < nextindex)
+		memmove(&p->xad[index + 1], &p->xad[index],
+			(nextindex - index) * sizeof(xad_t));
+
+	/* insert the new entry: mark the entry NEW */
+	xad = &p->xad[index];
+	XT_PUTENTRY(xad, xflag, xoff, xlen, xaddr);
+
+	/* advance next available entry index */
+	le16_add_cpu(&p->header.nextindex, 1);
+
+	/* Don't log it if there are no links to the file */
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW);
+		xtlck = (struct xtlock *) & tlck->lock;
+		xtlck->lwm.offset =
+		    (xtlck->lwm.offset) ? min(index,
+					      (int)xtlck->lwm.offset) : index;
+		xtlck->lwm.length =
+		    le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset;
+	}
+
+	*xaddrp = xaddr;
+
+      out:
+	/* unpin the leaf page */
+	XT_PUTPAGE(mp);
+
+	return rc;
+}
+
+
+/*
+ *	xtSplitUp()
+ *
+ * function:
+ *	split full pages as propagating insertion up the tree
+ *
+ * parameter:
+ *	tid	- transaction id;
+ *	ip	- file object;
+ *	split	- entry parameter descriptor;
+ *	btstack - traverse stack from xtSearch()
+ *
+ * return:
+ */
+static int
+xtSplitUp(tid_t tid,
+	  struct inode *ip, struct xtsplit * split, struct btstack * btstack)
+{
+	int rc = 0;
+	struct metapage *smp;
+	xtpage_t *sp;		/* split page */
+	struct metapage *rmp;
+	s64 rbn;		/* new right page block number */
+	struct metapage *rcmp;
+	xtpage_t *rcp;		/* right child page */
+	s64 rcbn;		/* right child page block number */
+	int skip;		/* index of entry of insertion */
+	int nextindex;		/* next available entry index of p */
+	struct btframe *parent;	/* parent page entry on traverse stack */
+	xad_t *xad;
+	s64 xaddr;
+	int xlen;
+	int nsplit;		/* number of pages split */
+	struct pxdlist pxdlist;
+	pxd_t *pxd;
+	struct tlock *tlck;
+	struct xtlock *xtlck;
+
+	smp = split->mp;
+	sp = XT_PAGE(ip, smp);
+
+	/* is inode xtree root extension/inline EA area free ? */
+	if ((sp->header.flag & BT_ROOT) && (!S_ISDIR(ip->i_mode)) &&
+	    (le16_to_cpu(sp->header.maxentry) < XTROOTMAXSLOT) &&
+	    (JFS_IP(ip)->mode2 & INLINEEA)) {
+		sp->header.maxentry = cpu_to_le16(XTROOTMAXSLOT);
+		JFS_IP(ip)->mode2 &= ~INLINEEA;
+
+		BT_MARK_DIRTY(smp, ip);
+		/*
+		 * acquire a transaction lock on the leaf page;
+		 *
+		 * action: xad insertion/extension;
+		 */
+
+		/* if insert into middle, shift right remaining entries. */
+		skip = split->index;
+		nextindex = le16_to_cpu(sp->header.nextindex);
+		if (skip < nextindex)
+			memmove(&sp->xad[skip + 1], &sp->xad[skip],
+				(nextindex - skip) * sizeof(xad_t));
+
+		/* insert the new entry: mark the entry NEW */
+		xad = &sp->xad[skip];
+		XT_PUTENTRY(xad, split->flag, split->off, split->len,
+			    split->addr);
+
+		/* advance next available entry index */
+		le16_add_cpu(&sp->header.nextindex, 1);
+
+		/* Don't log it if there are no links to the file */
+		if (!test_cflag(COMMIT_Nolink, ip)) {
+			tlck = txLock(tid, ip, smp, tlckXTREE | tlckGROW);
+			xtlck = (struct xtlock *) & tlck->lock;
+			xtlck->lwm.offset = (xtlck->lwm.offset) ?
+			    min(skip, (int)xtlck->lwm.offset) : skip;
+			xtlck->lwm.length =
+			    le16_to_cpu(sp->header.nextindex) -
+			    xtlck->lwm.offset;
+		}
+
+		return 0;
+	}
+
+	/*
+	 * allocate new index blocks to cover index page split(s)
+	 *
+	 * allocation hint: ?
+	 */
+	if (split->pxdlist == NULL) {
+		nsplit = btstack->nsplit;
+		split->pxdlist = &pxdlist;
+		pxdlist.maxnpxd = pxdlist.npxd = 0;
+		pxd = &pxdlist.pxd[0];
+		xlen = JFS_SBI(ip->i_sb)->nbperpage;
+		for (; nsplit > 0; nsplit--, pxd++) {
+			if ((rc = dbAlloc(ip, (s64) 0, (s64) xlen, &xaddr))
+			    == 0) {
+				PXDaddress(pxd, xaddr);
+				PXDlength(pxd, xlen);
+
+				pxdlist.maxnpxd++;
+
+				continue;
+			}
+
+			/* undo allocation */
+
+			XT_PUTPAGE(smp);
+			return rc;
+		}
+	}
+
+	/*
+	 * Split leaf page <sp> into <sp> and a new right page <rp>.
+	 *
+	 * The split routines insert the new entry into the leaf page,
+	 * and acquire txLock as appropriate.
+	 * return <rp> pinned and its block number <rpbn>.
+	 */
+	rc = (sp->header.flag & BT_ROOT) ?
+	    xtSplitRoot(tid, ip, split, &rmp) :
+	    xtSplitPage(tid, ip, split, &rmp, &rbn);
+
+	XT_PUTPAGE(smp);
+
+	if (rc)
+		return -EIO;
+	/*
+	 * propagate up the router entry for the leaf page just split
+	 *
+	 * insert a router entry for the new page into the parent page,
+	 * propagate the insert/split up the tree by walking back the stack
+	 * of (bn of parent page, index of child page entry in parent page)
+	 * that were traversed during the search for the page that split.
+	 *
+	 * the propagation of insert/split up the tree stops if the root
+	 * splits or the page inserted into doesn't have to split to hold
+	 * the new entry.
+	 *
+	 * the parent entry for the split page remains the same, and
+	 * a new entry is inserted at its right with the first key and
+	 * block number of the new right page.
+	 *
+	 * There are a maximum of 3 pages pinned at any time:
+	 * right child, left parent and right parent (when the parent splits)
+	 * to keep the child page pinned while working on the parent.
+	 * make sure that all pins are released at exit.
+	 */
+	while ((parent = BT_POP(btstack)) != NULL) {
+		/* parent page specified by stack frame <parent> */
+
+		/* keep current child pages <rcp> pinned */
+		rcmp = rmp;
+		rcbn = rbn;
+		rcp = XT_PAGE(ip, rcmp);
+
+		/*
+		 * insert router entry in parent for new right child page <rp>
+		 */
+		/* get/pin the parent page <sp> */
+		XT_GETPAGE(ip, parent->bn, smp, PSIZE, sp, rc);
+		if (rc) {
+			XT_PUTPAGE(rcmp);
+			return rc;
+		}
+
+		/*
+		 * The new key entry goes ONE AFTER the index of parent entry,
+		 * because the split was to the right.
+		 */
+		skip = parent->index + 1;
+
+		/*
+		 * split or shift right remaining entries of the parent page
+		 */
+		nextindex = le16_to_cpu(sp->header.nextindex);
+		/*
+		 * parent page is full - split the parent page
+		 */
+		if (nextindex == le16_to_cpu(sp->header.maxentry)) {
+			/* init for parent page split */
+			split->mp = smp;
+			split->index = skip;	/* index at insert */
+			split->flag = XAD_NEW;
+			split->off = offsetXAD(&rcp->xad[XTENTRYSTART]);
+			split->len = JFS_SBI(ip->i_sb)->nbperpage;
+			split->addr = rcbn;
+
+			/* unpin previous right child page */
+			XT_PUTPAGE(rcmp);
+
+			/* The split routines insert the new entry,
+			 * and acquire txLock as appropriate.
+			 * return <rp> pinned and its block number <rpbn>.
+			 */
+			rc = (sp->header.flag & BT_ROOT) ?
+			    xtSplitRoot(tid, ip, split, &rmp) :
+			    xtSplitPage(tid, ip, split, &rmp, &rbn);
+			if (rc) {
+				XT_PUTPAGE(smp);
+				return rc;
+			}
+
+			XT_PUTPAGE(smp);
+			/* keep new child page <rp> pinned */
+		}
+		/*
+		 * parent page is not full - insert in parent page
+		 */
+		else {
+			/*
+			 * insert router entry in parent for the right child
+			 * page from the first entry of the right child page:
+			 */
+			/*
+			 * acquire a transaction lock on the parent page;
+			 *
+			 * action: router xad insertion;
+			 */
+			BT_MARK_DIRTY(smp, ip);
+
+			/*
+			 * if insert into middle, shift right remaining entries
+			 */
+			if (skip < nextindex)
+				memmove(&sp->xad[skip + 1], &sp->xad[skip],
+					(nextindex -
+					 skip) << L2XTSLOTSIZE);
+
+			/* insert the router entry */
+			xad = &sp->xad[skip];
+			XT_PUTENTRY(xad, XAD_NEW,
+				    offsetXAD(&rcp->xad[XTENTRYSTART]),
+				    JFS_SBI(ip->i_sb)->nbperpage, rcbn);
+
+			/* advance next available entry index. */
+			le16_add_cpu(&sp->header.nextindex, 1);
+
+			/* Don't log it if there are no links to the file */
+			if (!test_cflag(COMMIT_Nolink, ip)) {
+				tlck = txLock(tid, ip, smp,
+					      tlckXTREE | tlckGROW);
+				xtlck = (struct xtlock *) & tlck->lock;
+				xtlck->lwm.offset = (xtlck->lwm.offset) ?
+				    min(skip, (int)xtlck->lwm.offset) : skip;
+				xtlck->lwm.length =
+				    le16_to_cpu(sp->header.nextindex) -
+				    xtlck->lwm.offset;
+			}
+
+			/* unpin parent page */
+			XT_PUTPAGE(smp);
+
+			/* exit propagate up */
+			break;
+		}
+	}
+
+	/* unpin current right page */
+	XT_PUTPAGE(rmp);
+
+	return 0;
+}
+
+
+/*
+ *	xtSplitPage()
+ *
+ * function:
+ *	split a full non-root page into
+ *	original/split/left page and new right page
+ *	i.e., the original/split page remains as left page.
+ *
+ * parameter:
+ *	int		tid,
+ *	struct inode	*ip,
+ *	struct xtsplit	*split,
+ *	struct metapage	**rmpp,
+ *	u64		*rbnp,
+ *
+ * return:
+ *	Pointer to page in which to insert or NULL on error.
+ */
+static int
+xtSplitPage(tid_t tid, struct inode *ip,
+	    struct xtsplit * split, struct metapage ** rmpp, s64 * rbnp)
+{
+	int rc = 0;
+	struct metapage *smp;
+	xtpage_t *sp;
+	struct metapage *rmp;
+	xtpage_t *rp;		/* new right page allocated */
+	s64 rbn;		/* new right page block number */
+	struct metapage *mp;
+	xtpage_t *p;
+	s64 nextbn;
+	int skip, maxentry, middle, righthalf, n;
+	xad_t *xad;
+	struct pxdlist *pxdlist;
+	pxd_t *pxd;
+	struct tlock *tlck;
+	struct xtlock *sxtlck = NULL, *rxtlck = NULL;
+	int quota_allocation = 0;
+
+	smp = split->mp;
+	sp = XT_PAGE(ip, smp);
+
+	INCREMENT(xtStat.split);
+
+	pxdlist = split->pxdlist;
+	pxd = &pxdlist->pxd[pxdlist->npxd];
+	pxdlist->npxd++;
+	rbn = addressPXD(pxd);
+
+	/* Allocate blocks to quota. */
+	rc = dquot_alloc_block(ip, lengthPXD(pxd));
+	if (rc)
+		goto clean_up;
+
+	quota_allocation += lengthPXD(pxd);
+
+	/*
+	 * allocate the new right page for the split
+	 */
+	rmp = get_metapage(ip, rbn, PSIZE, 1);
+	if (rmp == NULL) {
+		rc = -EIO;
+		goto clean_up;
+	}
+
+	jfs_info("xtSplitPage: ip:0x%p smp:0x%p rmp:0x%p", ip, smp, rmp);
+
+	BT_MARK_DIRTY(rmp, ip);
+	/*
+	 * action: new page;
+	 */
+
+	rp = (xtpage_t *) rmp->data;
+	rp->header.self = *pxd;
+	rp->header.flag = sp->header.flag & BT_TYPE;
+	rp->header.maxentry = sp->header.maxentry;	/* little-endian */
+	rp->header.nextindex = cpu_to_le16(XTENTRYSTART);
+
+	BT_MARK_DIRTY(smp, ip);
+	/* Don't log it if there are no links to the file */
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		/*
+		 * acquire a transaction lock on the new right page;
+		 */
+		tlck = txLock(tid, ip, rmp, tlckXTREE | tlckNEW);
+		rxtlck = (struct xtlock *) & tlck->lock;
+		rxtlck->lwm.offset = XTENTRYSTART;
+		/*
+		 * acquire a transaction lock on the split page
+		 */
+		tlck = txLock(tid, ip, smp, tlckXTREE | tlckGROW);
+		sxtlck = (struct xtlock *) & tlck->lock;
+	}
+
+	/*
+	 * initialize/update sibling pointers of <sp> and <rp>
+	 */
+	nextbn = le64_to_cpu(sp->header.next);
+	rp->header.next = cpu_to_le64(nextbn);
+	rp->header.prev = cpu_to_le64(addressPXD(&sp->header.self));
+	sp->header.next = cpu_to_le64(rbn);
+
+	skip = split->index;
+
+	/*
+	 *	sequential append at tail (after last entry of last page)
+	 *
+	 * if splitting the last page on a level because of appending
+	 * a entry to it (skip is maxentry), it's likely that the access is
+	 * sequential. adding an empty page on the side of the level is less
+	 * work and can push the fill factor much higher than normal.
+	 * if we're wrong it's no big deal -  we will do the split the right
+	 * way next time.
+	 * (it may look like it's equally easy to do a similar hack for
+	 * reverse sorted data, that is, split the tree left, but it's not.
+	 * Be my guest.)
+	 */
+	if (nextbn == 0 && skip == le16_to_cpu(sp->header.maxentry)) {
+		/*
+		 * acquire a transaction lock on the new/right page;
+		 *
+		 * action: xad insertion;
+		 */
+		/* insert entry at the first entry of the new right page */
+		xad = &rp->xad[XTENTRYSTART];
+		XT_PUTENTRY(xad, split->flag, split->off, split->len,
+			    split->addr);
+
+		rp->header.nextindex = cpu_to_le16(XTENTRYSTART + 1);
+
+		if (!test_cflag(COMMIT_Nolink, ip)) {
+			/* rxtlck->lwm.offset = XTENTRYSTART; */
+			rxtlck->lwm.length = 1;
+		}
+
+		*rmpp = rmp;
+		*rbnp = rbn;
+
+		jfs_info("xtSplitPage: sp:0x%p rp:0x%p", sp, rp);
+		return 0;
+	}
+
+	/*
+	 *	non-sequential insert (at possibly middle page)
+	 */
+
+	/*
+	 * update previous pointer of old next/right page of <sp>
+	 */
+	if (nextbn != 0) {
+		XT_GETPAGE(ip, nextbn, mp, PSIZE, p, rc);
+		if (rc) {
+			XT_PUTPAGE(rmp);
+			goto clean_up;
+		}
+
+		BT_MARK_DIRTY(mp, ip);
+		/*
+		 * acquire a transaction lock on the next page;
+		 *
+		 * action:sibling pointer update;
+		 */
+		if (!test_cflag(COMMIT_Nolink, ip))
+			tlck = txLock(tid, ip, mp, tlckXTREE | tlckRELINK);
+
+		p->header.prev = cpu_to_le64(rbn);
+
+		/* sibling page may have been updated previously, or
+		 * it may be updated later;
+		 */
+
+		XT_PUTPAGE(mp);
+	}
+
+	/*
+	 * split the data between the split and new/right pages
+	 */
+	maxentry = le16_to_cpu(sp->header.maxentry);
+	middle = maxentry >> 1;
+	righthalf = maxentry - middle;
+
+	/*
+	 * skip index in old split/left page - insert into left page:
+	 */
+	if (skip <= middle) {
+		/* move right half of split page to the new right page */
+		memmove(&rp->xad[XTENTRYSTART], &sp->xad[middle],
+			righthalf << L2XTSLOTSIZE);
+
+		/* shift right tail of left half to make room for new entry */
+		if (skip < middle)
+			memmove(&sp->xad[skip + 1], &sp->xad[skip],
+				(middle - skip) << L2XTSLOTSIZE);
+
+		/* insert new entry */
+		xad = &sp->xad[skip];
+		XT_PUTENTRY(xad, split->flag, split->off, split->len,
+			    split->addr);
+
+		/* update page header */
+		sp->header.nextindex = cpu_to_le16(middle + 1);
+		if (!test_cflag(COMMIT_Nolink, ip)) {
+			sxtlck->lwm.offset = (sxtlck->lwm.offset) ?
+			    min(skip, (int)sxtlck->lwm.offset) : skip;
+		}
+
+		rp->header.nextindex =
+		    cpu_to_le16(XTENTRYSTART + righthalf);
+	}
+	/*
+	 * skip index in new right page - insert into right page:
+	 */
+	else {
+		/* move left head of right half to right page */
+		n = skip - middle;
+		memmove(&rp->xad[XTENTRYSTART], &sp->xad[middle],
+			n << L2XTSLOTSIZE);
+
+		/* insert new entry */
+		n += XTENTRYSTART;
+		xad = &rp->xad[n];
+		XT_PUTENTRY(xad, split->flag, split->off, split->len,
+			    split->addr);
+
+		/* move right tail of right half to right page */
+		if (skip < maxentry)
+			memmove(&rp->xad[n + 1], &sp->xad[skip],
+				(maxentry - skip) << L2XTSLOTSIZE);
+
+		/* update page header */
+		sp->header.nextindex = cpu_to_le16(middle);
+		if (!test_cflag(COMMIT_Nolink, ip)) {
+			sxtlck->lwm.offset = (sxtlck->lwm.offset) ?
+			    min(middle, (int)sxtlck->lwm.offset) : middle;
+		}
+
+		rp->header.nextindex = cpu_to_le16(XTENTRYSTART +
+						   righthalf + 1);
+	}
+
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		sxtlck->lwm.length = le16_to_cpu(sp->header.nextindex) -
+		    sxtlck->lwm.offset;
+
+		/* rxtlck->lwm.offset = XTENTRYSTART; */
+		rxtlck->lwm.length = le16_to_cpu(rp->header.nextindex) -
+		    XTENTRYSTART;
+	}
+
+	*rmpp = rmp;
+	*rbnp = rbn;
+
+	jfs_info("xtSplitPage: sp:0x%p rp:0x%p", sp, rp);
+	return rc;
+
+      clean_up:
+
+	/* Rollback quota allocation. */
+	if (quota_allocation)
+		dquot_free_block(ip, quota_allocation);
+
+	return (rc);
+}
+
+
+/*
+ *	xtSplitRoot()
+ *
+ * function:
+ *	split the full root page into original/root/split page and new
+ *	right page
+ *	i.e., root remains fixed in tree anchor (inode) and the root is
+ *	copied to a single new right child page since root page <<
+ *	non-root page, and the split root page contains a single entry
+ *	for the new right child page.
+ *
+ * parameter:
+ *	int		tid,
+ *	struct inode	*ip,
+ *	struct xtsplit	*split,
+ *	struct metapage	**rmpp)
+ *
+ * return:
+ *	Pointer to page in which to insert or NULL on error.
+ */
+static int
+xtSplitRoot(tid_t tid,
+	    struct inode *ip, struct xtsplit * split, struct metapage ** rmpp)
+{
+	xtpage_t *sp;
+	struct metapage *rmp;
+	xtpage_t *rp;
+	s64 rbn;
+	int skip, nextindex;
+	xad_t *xad;
+	pxd_t *pxd;
+	struct pxdlist *pxdlist;
+	struct tlock *tlck;
+	struct xtlock *xtlck;
+	int rc;
+
+	sp = &JFS_IP(ip)->i_xtroot;
+
+	INCREMENT(xtStat.split);
+
+	/*
+	 *	allocate a single (right) child page
+	 */
+	pxdlist = split->pxdlist;
+	pxd = &pxdlist->pxd[pxdlist->npxd];
+	pxdlist->npxd++;
+	rbn = addressPXD(pxd);
+	rmp = get_metapage(ip, rbn, PSIZE, 1);
+	if (rmp == NULL)
+		return -EIO;
+
+	/* Allocate blocks to quota. */
+	rc = dquot_alloc_block(ip, lengthPXD(pxd));
+	if (rc) {
+		release_metapage(rmp);
+		return rc;
+	}
+
+	jfs_info("xtSplitRoot: ip:0x%p rmp:0x%p", ip, rmp);
+
+	/*
+	 * acquire a transaction lock on the new right page;
+	 *
+	 * action: new page;
+	 */
+	BT_MARK_DIRTY(rmp, ip);
+
+	rp = (xtpage_t *) rmp->data;
+	rp->header.flag =
+	    (sp->header.flag & BT_LEAF) ? BT_LEAF : BT_INTERNAL;
+	rp->header.self = *pxd;
+	rp->header.nextindex = cpu_to_le16(XTENTRYSTART);
+	rp->header.maxentry = cpu_to_le16(PSIZE >> L2XTSLOTSIZE);
+
+	/* initialize sibling pointers */
+	rp->header.next = 0;
+	rp->header.prev = 0;
+
+	/*
+	 * copy the in-line root page into new right page extent
+	 */
+	nextindex = le16_to_cpu(sp->header.maxentry);
+	memmove(&rp->xad[XTENTRYSTART], &sp->xad[XTENTRYSTART],
+		(nextindex - XTENTRYSTART) << L2XTSLOTSIZE);
+
+	/*
+	 * insert the new entry into the new right/child page
+	 * (skip index in the new right page will not change)
+	 */
+	skip = split->index;
+	/* if insert into middle, shift right remaining entries */
+	if (skip != nextindex)
+		memmove(&rp->xad[skip + 1], &rp->xad[skip],
+			(nextindex - skip) * sizeof(xad_t));
+
+	xad = &rp->xad[skip];
+	XT_PUTENTRY(xad, split->flag, split->off, split->len, split->addr);
+
+	/* update page header */
+	rp->header.nextindex = cpu_to_le16(nextindex + 1);
+
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		tlck = txLock(tid, ip, rmp, tlckXTREE | tlckNEW);
+		xtlck = (struct xtlock *) & tlck->lock;
+		xtlck->lwm.offset = XTENTRYSTART;
+		xtlck->lwm.length = le16_to_cpu(rp->header.nextindex) -
+		    XTENTRYSTART;
+	}
+
+	/*
+	 *	reset the root
+	 *
+	 * init root with the single entry for the new right page
+	 * set the 1st entry offset to 0, which force the left-most key
+	 * at any level of the tree to be less than any search key.
+	 */
+	/*
+	 * acquire a transaction lock on the root page (in-memory inode);
+	 *
+	 * action: root split;
+	 */
+	BT_MARK_DIRTY(split->mp, ip);
+
+	xad = &sp->xad[XTENTRYSTART];
+	XT_PUTENTRY(xad, XAD_NEW, 0, JFS_SBI(ip->i_sb)->nbperpage, rbn);
+
+	/* update page header of root */
+	sp->header.flag &= ~BT_LEAF;
+	sp->header.flag |= BT_INTERNAL;
+
+	sp->header.nextindex = cpu_to_le16(XTENTRYSTART + 1);
+
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		tlck = txLock(tid, ip, split->mp, tlckXTREE | tlckGROW);
+		xtlck = (struct xtlock *) & tlck->lock;
+		xtlck->lwm.offset = XTENTRYSTART;
+		xtlck->lwm.length = 1;
+	}
+
+	*rmpp = rmp;
+
+	jfs_info("xtSplitRoot: sp:0x%p rp:0x%p", sp, rp);
+	return 0;
+}
+
+
+/*
+ *	xtExtend()
+ *
+ * function: extend in-place;
+ *
+ * note: existing extent may or may not have been committed.
+ * caller is responsible for pager buffer cache update, and
+ * working block allocation map update;
+ * update pmap: alloc whole extended extent;
+ */
+int xtExtend(tid_t tid,		/* transaction id */
+	     struct inode *ip, s64 xoff,	/* delta extent offset */
+	     s32 xlen,		/* delta extent length */
+	     int flag)
+{
+	int rc = 0;
+	int cmp;
+	struct metapage *mp;	/* meta-page buffer */
+	xtpage_t *p;		/* base B+-tree index page */
+	s64 bn;
+	int index, nextindex, len;
+	struct btstack btstack;	/* traverse stack */
+	struct xtsplit split;	/* split information */
+	xad_t *xad;
+	s64 xaddr;
+	struct tlock *tlck;
+	struct xtlock *xtlck = NULL;
+
+	jfs_info("xtExtend: nxoff:0x%lx nxlen:0x%x", (ulong) xoff, xlen);
+
+	/* there must exist extent to be extended */
+	if ((rc = xtSearch(ip, xoff - 1, NULL, &cmp, &btstack, XT_INSERT)))
+		return rc;
+
+	/* retrieve search result */
+	XT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+	if (cmp != 0) {
+		XT_PUTPAGE(mp);
+		jfs_error(ip->i_sb, "xtSearch did not find extent\n");
+		return -EIO;
+	}
+
+	/* extension must be contiguous */
+	xad = &p->xad[index];
+	if ((offsetXAD(xad) + lengthXAD(xad)) != xoff) {
+		XT_PUTPAGE(mp);
+		jfs_error(ip->i_sb, "extension is not contiguous\n");
+		return -EIO;
+	}
+
+	/*
+	 * acquire a transaction lock on the leaf page;
+	 *
+	 * action: xad insertion/extension;
+	 */
+	BT_MARK_DIRTY(mp, ip);
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW);
+		xtlck = (struct xtlock *) & tlck->lock;
+	}
+
+	/* extend will overflow extent ? */
+	xlen = lengthXAD(xad) + xlen;
+	if ((len = xlen - MAXXLEN) <= 0)
+		goto extendOld;
+
+	/*
+	 *	extent overflow: insert entry for new extent
+	 */
+//insertNew:
+	xoff = offsetXAD(xad) + MAXXLEN;
+	xaddr = addressXAD(xad) + MAXXLEN;
+	nextindex = le16_to_cpu(p->header.nextindex);
+
+	/*
+	 *	if the leaf page is full, insert the new entry and
+	 *	propagate up the router entry for the new page from split
+	 *
+	 * The xtSplitUp() will insert the entry and unpin the leaf page.
+	 */
+	if (nextindex == le16_to_cpu(p->header.maxentry)) {
+		/* xtSpliUp() unpins leaf pages */
+		split.mp = mp;
+		split.index = index + 1;
+		split.flag = XAD_NEW;
+		split.off = xoff;	/* split offset */
+		split.len = len;
+		split.addr = xaddr;
+		split.pxdlist = NULL;
+		if ((rc = xtSplitUp(tid, ip, &split, &btstack)))
+			return rc;
+
+		/* get back old page */
+		XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+		/*
+		 * if leaf root has been split, original root has been
+		 * copied to new child page, i.e., original entry now
+		 * resides on the new child page;
+		 */
+		if (p->header.flag & BT_INTERNAL) {
+			ASSERT(p->header.nextindex ==
+			       cpu_to_le16(XTENTRYSTART + 1));
+			xad = &p->xad[XTENTRYSTART];
+			bn = addressXAD(xad);
+			XT_PUTPAGE(mp);
+
+			/* get new child page */
+			XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+			if (rc)
+				return rc;
+
+			BT_MARK_DIRTY(mp, ip);
+			if (!test_cflag(COMMIT_Nolink, ip)) {
+				tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW);
+				xtlck = (struct xtlock *) & tlck->lock;
+			}
+		}
+	}
+	/*
+	 *	insert the new entry into the leaf page
+	 */
+	else {
+		/* insert the new entry: mark the entry NEW */
+		xad = &p->xad[index + 1];
+		XT_PUTENTRY(xad, XAD_NEW, xoff, len, xaddr);
+
+		/* advance next available entry index */
+		le16_add_cpu(&p->header.nextindex, 1);
+	}
+
+	/* get back old entry */
+	xad = &p->xad[index];
+	xlen = MAXXLEN;
+
+	/*
+	 * extend old extent
+	 */
+      extendOld:
+	XADlength(xad, xlen);
+	if (!(xad->flag & XAD_NEW))
+		xad->flag |= XAD_EXTENDED;
+
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		xtlck->lwm.offset =
+		    (xtlck->lwm.offset) ? min(index,
+					      (int)xtlck->lwm.offset) : index;
+		xtlck->lwm.length =
+		    le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset;
+	}
+
+	/* unpin the leaf page */
+	XT_PUTPAGE(mp);
+
+	return rc;
+}
+
+/*
+ *	xtUpdate()
+ *
+ * function: update XAD;
+ *
+ *	update extent for allocated_but_not_recorded or
+ *	compressed extent;
+ *
+ * parameter:
+ *	nxad	- new XAD;
+ *		logical extent of the specified XAD must be completely
+ *		contained by an existing XAD;
+ */
+int xtUpdate(tid_t tid, struct inode *ip, xad_t * nxad)
+{				/* new XAD */
+	int rc = 0;
+	int cmp;
+	struct metapage *mp;	/* meta-page buffer */
+	xtpage_t *p;		/* base B+-tree index page */
+	s64 bn;
+	int index0, index, newindex, nextindex;
+	struct btstack btstack;	/* traverse stack */
+	struct xtsplit split;	/* split information */
+	xad_t *xad, *lxad, *rxad;
+	int xflag;
+	s64 nxoff, xoff;
+	int nxlen, xlen, lxlen, rxlen;
+	s64 nxaddr, xaddr;
+	struct tlock *tlck;
+	struct xtlock *xtlck = NULL;
+	int newpage = 0;
+
+	/* there must exist extent to be tailgated */
+	nxoff = offsetXAD(nxad);
+	nxlen = lengthXAD(nxad);
+	nxaddr = addressXAD(nxad);
+
+	if ((rc = xtSearch(ip, nxoff, NULL, &cmp, &btstack, XT_INSERT)))
+		return rc;
+
+	/* retrieve search result */
+	XT_GETSEARCH(ip, btstack.top, bn, mp, p, index0);
+
+	if (cmp != 0) {
+		XT_PUTPAGE(mp);
+		jfs_error(ip->i_sb, "Could not find extent\n");
+		return -EIO;
+	}
+
+	BT_MARK_DIRTY(mp, ip);
+	/*
+	 * acquire tlock of the leaf page containing original entry
+	 */
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW);
+		xtlck = (struct xtlock *) & tlck->lock;
+	}
+
+	xad = &p->xad[index0];
+	xflag = xad->flag;
+	xoff = offsetXAD(xad);
+	xlen = lengthXAD(xad);
+	xaddr = addressXAD(xad);
+
+	/* nXAD must be completely contained within XAD */
+	if ((xoff > nxoff) ||
+	    (nxoff + nxlen > xoff + xlen)) {
+		XT_PUTPAGE(mp);
+		jfs_error(ip->i_sb,
+			  "nXAD in not completely contained within XAD\n");
+		return -EIO;
+	}
+
+	index = index0;
+	newindex = index + 1;
+	nextindex = le16_to_cpu(p->header.nextindex);
+
+	if (xoff < nxoff)
+		goto coalesceRight;
+
+	/*
+	 * coalesce with left XAD
+	 */
+	/* is XAD first entry of page ? */
+	if (index == XTENTRYSTART)
+		goto replace;
+
+	/* is nXAD logically and physically contiguous with lXAD ? */
+	lxad = &p->xad[index - 1];
+	lxlen = lengthXAD(lxad);
+	if (!(lxad->flag & XAD_NOTRECORDED) &&
+	    (nxoff == offsetXAD(lxad) + lxlen) &&
+	    (nxaddr == addressXAD(lxad) + lxlen) &&
+	    (lxlen + nxlen < MAXXLEN)) {
+		/* extend right lXAD */
+		index0 = index - 1;
+		XADlength(lxad, lxlen + nxlen);
+
+		/* If we just merged two extents together, need to make sure the
+		 * right extent gets logged.  If the left one is marked XAD_NEW,
+		 * then we know it will be logged.  Otherwise, mark as
+		 * XAD_EXTENDED
+		 */
+		if (!(lxad->flag & XAD_NEW))
+			lxad->flag |= XAD_EXTENDED;
+
+		if (xlen > nxlen) {
+			/* truncate XAD */
+			XADoffset(xad, xoff + nxlen);
+			XADlength(xad, xlen - nxlen);
+			XADaddress(xad, xaddr + nxlen);
+			goto out;
+		} else {	/* (xlen == nxlen) */
+
+			/* remove XAD */
+			if (index < nextindex - 1)
+				memmove(&p->xad[index], &p->xad[index + 1],
+					(nextindex - index -
+					 1) << L2XTSLOTSIZE);
+
+			p->header.nextindex =
+			    cpu_to_le16(le16_to_cpu(p->header.nextindex) -
+					1);
+
+			index = index0;
+			newindex = index + 1;
+			nextindex = le16_to_cpu(p->header.nextindex);
+			xoff = nxoff = offsetXAD(lxad);
+			xlen = nxlen = lxlen + nxlen;
+			xaddr = nxaddr = addressXAD(lxad);
+			goto coalesceRight;
+		}
+	}
+
+	/*
+	 * replace XAD with nXAD
+	 */
+      replace:			/* (nxoff == xoff) */
+	if (nxlen == xlen) {
+		/* replace XAD with nXAD:recorded */
+		*xad = *nxad;
+		xad->flag = xflag & ~XAD_NOTRECORDED;
+
+		goto coalesceRight;
+	} else			/* (nxlen < xlen) */
+		goto updateLeft;
+
+	/*
+	 * coalesce with right XAD
+	 */
+      coalesceRight:		/* (xoff <= nxoff) */
+	/* is XAD last entry of page ? */
+	if (newindex == nextindex) {
+		if (xoff == nxoff)
+			goto out;
+		goto updateRight;
+	}
+
+	/* is nXAD logically and physically contiguous with rXAD ? */
+	rxad = &p->xad[index + 1];
+	rxlen = lengthXAD(rxad);
+	if (!(rxad->flag & XAD_NOTRECORDED) &&
+	    (nxoff + nxlen == offsetXAD(rxad)) &&
+	    (nxaddr + nxlen == addressXAD(rxad)) &&
+	    (rxlen + nxlen < MAXXLEN)) {
+		/* extend left rXAD */
+		XADoffset(rxad, nxoff);
+		XADlength(rxad, rxlen + nxlen);
+		XADaddress(rxad, nxaddr);
+
+		/* If we just merged two extents together, need to make sure
+		 * the left extent gets logged.  If the right one is marked
+		 * XAD_NEW, then we know it will be logged.  Otherwise, mark as
+		 * XAD_EXTENDED
+		 */
+		if (!(rxad->flag & XAD_NEW))
+			rxad->flag |= XAD_EXTENDED;
+
+		if (xlen > nxlen)
+			/* truncate XAD */
+			XADlength(xad, xlen - nxlen);
+		else {		/* (xlen == nxlen) */
+
+			/* remove XAD */
+			memmove(&p->xad[index], &p->xad[index + 1],
+				(nextindex - index - 1) << L2XTSLOTSIZE);
+
+			p->header.nextindex =
+			    cpu_to_le16(le16_to_cpu(p->header.nextindex) -
+					1);
+		}
+
+		goto out;
+	} else if (xoff == nxoff)
+		goto out;
+
+	if (xoff >= nxoff) {
+		XT_PUTPAGE(mp);
+		jfs_error(ip->i_sb, "xoff >= nxoff\n");
+		return -EIO;
+	}
+
+	/*
+	 * split XAD into (lXAD, nXAD):
+	 *
+	 *          |---nXAD--->
+	 * --|----------XAD----------|--
+	 *   |-lXAD-|
+	 */
+      updateRight:		/* (xoff < nxoff) */
+	/* truncate old XAD as lXAD:not_recorded */
+	xad = &p->xad[index];
+	XADlength(xad, nxoff - xoff);
+
+	/* insert nXAD:recorded */
+	if (nextindex == le16_to_cpu(p->header.maxentry)) {
+
+		/* xtSpliUp() unpins leaf pages */
+		split.mp = mp;
+		split.index = newindex;
+		split.flag = xflag & ~XAD_NOTRECORDED;
+		split.off = nxoff;
+		split.len = nxlen;
+		split.addr = nxaddr;
+		split.pxdlist = NULL;
+		if ((rc = xtSplitUp(tid, ip, &split, &btstack)))
+			return rc;
+
+		/* get back old page */
+		XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+		/*
+		 * if leaf root has been split, original root has been
+		 * copied to new child page, i.e., original entry now
+		 * resides on the new child page;
+		 */
+		if (p->header.flag & BT_INTERNAL) {
+			ASSERT(p->header.nextindex ==
+			       cpu_to_le16(XTENTRYSTART + 1));
+			xad = &p->xad[XTENTRYSTART];
+			bn = addressXAD(xad);
+			XT_PUTPAGE(mp);
+
+			/* get new child page */
+			XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+			if (rc)
+				return rc;
+
+			BT_MARK_DIRTY(mp, ip);
+			if (!test_cflag(COMMIT_Nolink, ip)) {
+				tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW);
+				xtlck = (struct xtlock *) & tlck->lock;
+			}
+		} else {
+			/* is nXAD on new page ? */
+			if (newindex >
+			    (le16_to_cpu(p->header.maxentry) >> 1)) {
+				newindex =
+				    newindex -
+				    le16_to_cpu(p->header.nextindex) +
+				    XTENTRYSTART;
+				newpage = 1;
+			}
+		}
+	} else {
+		/* if insert into middle, shift right remaining entries */
+		if (newindex < nextindex)
+			memmove(&p->xad[newindex + 1], &p->xad[newindex],
+				(nextindex - newindex) << L2XTSLOTSIZE);
+
+		/* insert the entry */
+		xad = &p->xad[newindex];
+		*xad = *nxad;
+		xad->flag = xflag & ~XAD_NOTRECORDED;
+
+		/* advance next available entry index. */
+		p->header.nextindex =
+		    cpu_to_le16(le16_to_cpu(p->header.nextindex) + 1);
+	}
+
+	/*
+	 * does nXAD force 3-way split ?
+	 *
+	 *          |---nXAD--->|
+	 * --|----------XAD-------------|--
+	 *   |-lXAD-|           |-rXAD -|
+	 */
+	if (nxoff + nxlen == xoff + xlen)
+		goto out;
+
+	/* reorient nXAD as XAD for further split XAD into (nXAD, rXAD) */
+	if (newpage) {
+		/* close out old page */
+		if (!test_cflag(COMMIT_Nolink, ip)) {
+			xtlck->lwm.offset = (xtlck->lwm.offset) ?
+			    min(index0, (int)xtlck->lwm.offset) : index0;
+			xtlck->lwm.length =
+			    le16_to_cpu(p->header.nextindex) -
+			    xtlck->lwm.offset;
+		}
+
+		bn = le64_to_cpu(p->header.next);
+		XT_PUTPAGE(mp);
+
+		/* get new right page */
+		XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		BT_MARK_DIRTY(mp, ip);
+		if (!test_cflag(COMMIT_Nolink, ip)) {
+			tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW);
+			xtlck = (struct xtlock *) & tlck->lock;
+		}
+
+		index0 = index = newindex;
+	} else
+		index++;
+
+	newindex = index + 1;
+	nextindex = le16_to_cpu(p->header.nextindex);
+	xlen = xlen - (nxoff - xoff);
+	xoff = nxoff;
+	xaddr = nxaddr;
+
+	/* recompute split pages */
+	if (nextindex == le16_to_cpu(p->header.maxentry)) {
+		XT_PUTPAGE(mp);
+
+		if ((rc = xtSearch(ip, nxoff, NULL, &cmp, &btstack, XT_INSERT)))
+			return rc;
+
+		/* retrieve search result */
+		XT_GETSEARCH(ip, btstack.top, bn, mp, p, index0);
+
+		if (cmp != 0) {
+			XT_PUTPAGE(mp);
+			jfs_error(ip->i_sb, "xtSearch failed\n");
+			return -EIO;
+		}
+
+		if (index0 != index) {
+			XT_PUTPAGE(mp);
+			jfs_error(ip->i_sb, "unexpected value of index\n");
+			return -EIO;
+		}
+	}
+
+	/*
+	 * split XAD into (nXAD, rXAD)
+	 *
+	 *          ---nXAD---|
+	 * --|----------XAD----------|--
+	 *                    |-rXAD-|
+	 */
+      updateLeft:		/* (nxoff == xoff) && (nxlen < xlen) */
+	/* update old XAD with nXAD:recorded */
+	xad = &p->xad[index];
+	*xad = *nxad;
+	xad->flag = xflag & ~XAD_NOTRECORDED;
+
+	/* insert rXAD:not_recorded */
+	xoff = xoff + nxlen;
+	xlen = xlen - nxlen;
+	xaddr = xaddr + nxlen;
+	if (nextindex == le16_to_cpu(p->header.maxentry)) {
+/*
+printf("xtUpdate.updateLeft.split p:0x%p\n", p);
+*/
+		/* xtSpliUp() unpins leaf pages */
+		split.mp = mp;
+		split.index = newindex;
+		split.flag = xflag;
+		split.off = xoff;
+		split.len = xlen;
+		split.addr = xaddr;
+		split.pxdlist = NULL;
+		if ((rc = xtSplitUp(tid, ip, &split, &btstack)))
+			return rc;
+
+		/* get back old page */
+		XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		/*
+		 * if leaf root has been split, original root has been
+		 * copied to new child page, i.e., original entry now
+		 * resides on the new child page;
+		 */
+		if (p->header.flag & BT_INTERNAL) {
+			ASSERT(p->header.nextindex ==
+			       cpu_to_le16(XTENTRYSTART + 1));
+			xad = &p->xad[XTENTRYSTART];
+			bn = addressXAD(xad);
+			XT_PUTPAGE(mp);
+
+			/* get new child page */
+			XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+			if (rc)
+				return rc;
+
+			BT_MARK_DIRTY(mp, ip);
+			if (!test_cflag(COMMIT_Nolink, ip)) {
+				tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW);
+				xtlck = (struct xtlock *) & tlck->lock;
+			}
+		}
+	} else {
+		/* if insert into middle, shift right remaining entries */
+		if (newindex < nextindex)
+			memmove(&p->xad[newindex + 1], &p->xad[newindex],
+				(nextindex - newindex) << L2XTSLOTSIZE);
+
+		/* insert the entry */
+		xad = &p->xad[newindex];
+		XT_PUTENTRY(xad, xflag, xoff, xlen, xaddr);
+
+		/* advance next available entry index. */
+		p->header.nextindex =
+		    cpu_to_le16(le16_to_cpu(p->header.nextindex) + 1);
+	}
+
+      out:
+	if (!test_cflag(COMMIT_Nolink, ip)) {
+		xtlck->lwm.offset = (xtlck->lwm.offset) ?
+		    min(index0, (int)xtlck->lwm.offset) : index0;
+		xtlck->lwm.length = le16_to_cpu(p->header.nextindex) -
+		    xtlck->lwm.offset;
+	}
+
+	/* unpin the leaf page */
+	XT_PUTPAGE(mp);
+
+	return rc;
+}
+
+
+/*
+ *	xtAppend()
+ *
+ * function: grow in append mode from contiguous region specified ;
+ *
+ * parameter:
+ *	tid		- transaction id;
+ *	ip		- file object;
+ *	xflag		- extent flag:
+ *	xoff		- extent offset;
+ *	maxblocks	- max extent length;
+ *	xlen		- extent length (in/out);
+ *	xaddrp		- extent address pointer (in/out):
+ *	flag		-
+ *
+ * return:
+ */
+int xtAppend(tid_t tid,		/* transaction id */
+	     struct inode *ip, int xflag, s64 xoff, s32 maxblocks,
+	     s32 * xlenp,	/* (in/out) */
+	     s64 * xaddrp,	/* (in/out) */
+	     int flag)
+{
+	int rc = 0;
+	struct metapage *mp;	/* meta-page buffer */
+	xtpage_t *p;		/* base B+-tree index page */
+	s64 bn, xaddr;
+	int index, nextindex;
+	struct btstack btstack;	/* traverse stack */
+	struct xtsplit split;	/* split information */
+	xad_t *xad;
+	int cmp;
+	struct tlock *tlck;
+	struct xtlock *xtlck;
+	int nsplit, nblocks, xlen;
+	struct pxdlist pxdlist;
+	pxd_t *pxd;
+	s64 next;
+
+	xaddr = *xaddrp;
+	xlen = *xlenp;
+	jfs_info("xtAppend: xoff:0x%lx maxblocks:%d xlen:%d xaddr:0x%lx",
+		 (ulong) xoff, maxblocks, xlen, (ulong) xaddr);
+
+	/*
+	 *	search for the entry location at which to insert:
+	 *
+	 * xtFastSearch() and xtSearch() both returns (leaf page
+	 * pinned, index at which to insert).
+	 * n.b. xtSearch() may return index of maxentry of
+	 * the full page.
+	 */
+	if ((rc = xtSearch(ip, xoff, &next, &cmp, &btstack, XT_INSERT)))
+		return rc;
+
+	/* retrieve search result */
+	XT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+	if (cmp == 0) {
+		rc = -EEXIST;
+		goto out;
+	}
+
+	if (next)
+		xlen = min(xlen, (int)(next - xoff));
+//insert:
+	/*
+	 *	insert entry for new extent
+	 */
+	xflag |= XAD_NEW;
+
+	/*
+	 *	if the leaf page is full, split the page and
+	 *	propagate up the router entry for the new page from split
+	 *
+	 * The xtSplitUp() will insert the entry and unpin the leaf page.
+	 */
+	nextindex = le16_to_cpu(p->header.nextindex);
+	if (nextindex < le16_to_cpu(p->header.maxentry))
+		goto insertLeaf;
+
+	/*
+	 * allocate new index blocks to cover index page split(s)
+	 */
+	nsplit = btstack.nsplit;
+	split.pxdlist = &pxdlist;
+	pxdlist.maxnpxd = pxdlist.npxd = 0;
+	pxd = &pxdlist.pxd[0];
+	nblocks = JFS_SBI(ip->i_sb)->nbperpage;
+	for (; nsplit > 0; nsplit--, pxd++, xaddr += nblocks, maxblocks -= nblocks) {
+		if ((rc = dbAllocBottomUp(ip, xaddr, (s64) nblocks)) == 0) {
+			PXDaddress(pxd, xaddr);
+			PXDlength(pxd, nblocks);
+
+			pxdlist.maxnpxd++;
+
+			continue;
+		}
+
+		/* undo allocation */
+
+		goto out;
+	}
+
+	xlen = min(xlen, maxblocks);
+
+	/*
+	 * allocate data extent requested
+	 */
+	if ((rc = dbAllocBottomUp(ip, xaddr, (s64) xlen)))
+		goto out;
+
+	split.mp = mp;
+	split.index = index;
+	split.flag = xflag;
+	split.off = xoff;
+	split.len = xlen;
+	split.addr = xaddr;
+	if ((rc = xtSplitUp(tid, ip, &split, &btstack))) {
+		/* undo data extent allocation */
+		dbFree(ip, *xaddrp, (s64) * xlenp);
+
+		return rc;
+	}
+
+	*xaddrp = xaddr;
+	*xlenp = xlen;
+	return 0;
+
+	/*
+	 *	insert the new entry into the leaf page
+	 */
+      insertLeaf:
+	/*
+	 * allocate data extent requested
+	 */
+	if ((rc = dbAllocBottomUp(ip, xaddr, (s64) xlen)))
+		goto out;
+
+	BT_MARK_DIRTY(mp, ip);
+	/*
+	 * acquire a transaction lock on the leaf page;
+	 *
+	 * action: xad insertion/extension;
+	 */
+	tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW);
+	xtlck = (struct xtlock *) & tlck->lock;
+
+	/* insert the new entry: mark the entry NEW */
+	xad = &p->xad[index];
+	XT_PUTENTRY(xad, xflag, xoff, xlen, xaddr);
+
+	/* advance next available entry index */
+	le16_add_cpu(&p->header.nextindex, 1);
+
+	xtlck->lwm.offset =
+	    (xtlck->lwm.offset) ? min(index,(int) xtlck->lwm.offset) : index;
+	xtlck->lwm.length = le16_to_cpu(p->header.nextindex) -
+	    xtlck->lwm.offset;
+
+	*xaddrp = xaddr;
+	*xlenp = xlen;
+
+      out:
+	/* unpin the leaf page */
+	XT_PUTPAGE(mp);
+
+	return rc;
+}
+
+/*
+ *	xtInitRoot()
+ *
+ * initialize file root (inline in inode)
+ */
+void xtInitRoot(tid_t tid, struct inode *ip)
+{
+	xtpage_t *p;
+
+	/*
+	 * acquire a transaction lock on the root
+	 *
+	 * action:
+	 */
+	txLock(tid, ip, (struct metapage *) &JFS_IP(ip)->bxflag,
+		      tlckXTREE | tlckNEW);
+	p = &JFS_IP(ip)->i_xtroot;
+
+	p->header.flag = DXD_INDEX | BT_ROOT | BT_LEAF;
+	p->header.nextindex = cpu_to_le16(XTENTRYSTART);
+
+	if (S_ISDIR(ip->i_mode))
+		p->header.maxentry = cpu_to_le16(XTROOTINITSLOT_DIR);
+	else {
+		p->header.maxentry = cpu_to_le16(XTROOTINITSLOT);
+		ip->i_size = 0;
+	}
+
+
+	return;
+}
+
+
+/*
+ * We can run into a deadlock truncating a file with a large number of
+ * xtree pages (large fragmented file).  A robust fix would entail a
+ * reservation system where we would reserve a number of metadata pages
+ * and tlocks which we would be guaranteed without a deadlock.  Without
+ * this, a partial fix is to limit number of metadata pages we will lock
+ * in a single transaction.  Currently we will truncate the file so that
+ * no more than 50 leaf pages will be locked.  The caller of xtTruncate
+ * will be responsible for ensuring that the current transaction gets
+ * committed, and that subsequent transactions are created to truncate
+ * the file further if needed.
+ */
+#define MAX_TRUNCATE_LEAVES 50
+
+/*
+ *	xtTruncate()
+ *
+ * function:
+ *	traverse for truncation logging backward bottom up;
+ *	terminate at the last extent entry at the current subtree
+ *	root page covering new down size.
+ *	truncation may occur within the last extent entry.
+ *
+ * parameter:
+ *	int		tid,
+ *	struct inode	*ip,
+ *	s64		newsize,
+ *	int		type)	{PWMAP, PMAP, WMAP; DELETE, TRUNCATE}
+ *
+ * return:
+ *
+ * note:
+ *	PWMAP:
+ *	 1. truncate (non-COMMIT_NOLINK file)
+ *	    by jfs_truncate() or jfs_open(O_TRUNC):
+ *	    xtree is updated;
+ *	 2. truncate index table of directory when last entry removed
+ *	map update via tlock at commit time;
+ *	PMAP:
+ *	 Call xtTruncate_pmap instead
+ *	WMAP:
+ *	 1. remove (free zero link count) on last reference release
+ *	    (pmap has been freed at commit zero link count);
+ *	 2. truncate (COMMIT_NOLINK file, i.e., tmp file):
+ *	    xtree is updated;
+ *	 map update directly at truncation time;
+ *
+ *	if (DELETE)
+ *		no LOG_NOREDOPAGE is required (NOREDOFILE is sufficient);
+ *	else if (TRUNCATE)
+ *		must write LOG_NOREDOPAGE for deleted index page;
+ *
+ * pages may already have been tlocked by anonymous transactions
+ * during file growth (i.e., write) before truncation;
+ *
+ * except last truncated entry, deleted entries remains as is
+ * in the page (nextindex is updated) for other use
+ * (e.g., log/update allocation map): this avoid copying the page
+ * info but delay free of pages;
+ *
+ */
+s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int flag)
+{
+	int rc = 0;
+	s64 teof;
+	struct metapage *mp;
+	xtpage_t *p;
+	s64 bn;
+	int index, nextindex;
+	xad_t *xad;
+	s64 xoff, xaddr;
+	int xlen, len, freexlen;
+	struct btstack btstack;
+	struct btframe *parent;
+	struct tblock *tblk = NULL;
+	struct tlock *tlck = NULL;
+	struct xtlock *xtlck = NULL;
+	struct xdlistlock xadlock;	/* maplock for COMMIT_WMAP */
+	struct pxd_lock *pxdlock;		/* maplock for COMMIT_WMAP */
+	s64 nfreed;
+	int freed, log;
+	int locked_leaves = 0;
+
+	/* save object truncation type */
+	if (tid) {
+		tblk = tid_to_tblock(tid);
+		tblk->xflag |= flag;
+	}
+
+	nfreed = 0;
+
+	flag &= COMMIT_MAP;
+	assert(flag != COMMIT_PMAP);
+
+	if (flag == COMMIT_PWMAP)
+		log = 1;
+	else {
+		log = 0;
+		xadlock.flag = mlckFREEXADLIST;
+		xadlock.index = 1;
+	}
+
+	/*
+	 * if the newsize is not an integral number of pages,
+	 * the file between newsize and next page boundary will
+	 * be cleared.
+	 * if truncating into a file hole, it will cause
+	 * a full block to be allocated for the logical block.
+	 */
+
+	/*
+	 * release page blocks of truncated region <teof, eof>
+	 *
+	 * free the data blocks from the leaf index blocks.
+	 * delete the parent index entries corresponding to
+	 * the freed child data/index blocks.
+	 * free the index blocks themselves which aren't needed
+	 * in new sized file.
+	 *
+	 * index blocks are updated only if the blocks are to be
+	 * retained in the new sized file.
+	 * if type is PMAP, the data and index pages are NOT
+	 * freed, and the data and index blocks are NOT freed
+	 * from working map.
+	 * (this will allow continued access of data/index of
+	 * temporary file (zerolink count file truncated to zero-length)).
+	 */
+	teof = (newsize + (JFS_SBI(ip->i_sb)->bsize - 1)) >>
+	    JFS_SBI(ip->i_sb)->l2bsize;
+
+	/* clear stack */
+	BT_CLR(&btstack);
+
+	/*
+	 * start with root
+	 *
+	 * root resides in the inode
+	 */
+	bn = 0;
+
+	/*
+	 * first access of each page:
+	 */
+      getPage:
+	XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+	if (rc)
+		return rc;
+
+	/* process entries backward from last index */
+	index = le16_to_cpu(p->header.nextindex) - 1;
+
+
+	/* Since this is the rightmost page at this level, and we may have
+	 * already freed a page that was formerly to the right, let's make
+	 * sure that the next pointer is zero.
+	 */
+	if (p->header.next) {
+		if (log)
+			/*
+			 * Make sure this change to the header is logged.
+			 * If we really truncate this leaf, the flag
+			 * will be changed to tlckTRUNCATE
+			 */
+			tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW);
+		BT_MARK_DIRTY(mp, ip);
+		p->header.next = 0;
+	}
+
+	if (p->header.flag & BT_INTERNAL)
+		goto getChild;
+
+	/*
+	 *	leaf page
+	 */
+	freed = 0;
+
+	/* does region covered by leaf page precede Teof ? */
+	xad = &p->xad[index];
+	xoff = offsetXAD(xad);
+	xlen = lengthXAD(xad);
+	if (teof >= xoff + xlen) {
+		XT_PUTPAGE(mp);
+		goto getParent;
+	}
+
+	/* (re)acquire tlock of the leaf page */
+	if (log) {
+		if (++locked_leaves > MAX_TRUNCATE_LEAVES) {
+			/*
+			 * We need to limit the size of the transaction
+			 * to avoid exhausting pagecache & tlocks
+			 */
+			XT_PUTPAGE(mp);
+			newsize = (xoff + xlen) << JFS_SBI(ip->i_sb)->l2bsize;
+			goto getParent;
+		}
+		tlck = txLock(tid, ip, mp, tlckXTREE);
+		tlck->type = tlckXTREE | tlckTRUNCATE;
+		xtlck = (struct xtlock *) & tlck->lock;
+		xtlck->hwm.offset = le16_to_cpu(p->header.nextindex) - 1;
+	}
+	BT_MARK_DIRTY(mp, ip);
+
+	/*
+	 * scan backward leaf page entries
+	 */
+	for (; index >= XTENTRYSTART; index--) {
+		xad = &p->xad[index];
+		xoff = offsetXAD(xad);
+		xlen = lengthXAD(xad);
+		xaddr = addressXAD(xad);
+
+		/*
+		 * The "data" for a directory is indexed by the block
+		 * device's address space.  This metadata must be invalidated
+		 * here
+		 */
+		if (S_ISDIR(ip->i_mode) && (teof == 0))
+			invalidate_xad_metapages(ip, *xad);
+		/*
+		 * entry beyond eof: continue scan of current page
+		 *          xad
+		 * ---|---=======------->
+		 *   eof
+		 */
+		if (teof < xoff) {
+			nfreed += xlen;
+			continue;
+		}
+
+		/*
+		 * (xoff <= teof): last entry to be deleted from page;
+		 * If other entries remain in page: keep and update the page.
+		 */
+
+		/*
+		 * eof == entry_start: delete the entry
+		 *           xad
+		 * -------|=======------->
+		 *       eof
+		 *
+		 */
+		if (teof == xoff) {
+			nfreed += xlen;
+
+			if (index == XTENTRYSTART)
+				break;
+
+			nextindex = index;
+		}
+		/*
+		 * eof within the entry: truncate the entry.
+		 *          xad
+		 * -------===|===------->
+		 *          eof
+		 */
+		else if (teof < xoff + xlen) {
+			/* update truncated entry */
+			len = teof - xoff;
+			freexlen = xlen - len;
+			XADlength(xad, len);
+
+			/* save pxd of truncated extent in tlck */
+			xaddr += len;
+			if (log) {	/* COMMIT_PWMAP */
+				xtlck->lwm.offset = (xtlck->lwm.offset) ?
+				    min(index, (int)xtlck->lwm.offset) : index;
+				xtlck->lwm.length = index + 1 -
+				    xtlck->lwm.offset;
+				xtlck->twm.offset = index;
+				pxdlock = (struct pxd_lock *) & xtlck->pxdlock;
+				pxdlock->flag = mlckFREEPXD;
+				PXDaddress(&pxdlock->pxd, xaddr);
+				PXDlength(&pxdlock->pxd, freexlen);
+			}
+			/* free truncated extent */
+			else {	/* COMMIT_WMAP */
+
+				pxdlock = (struct pxd_lock *) & xadlock;
+				pxdlock->flag = mlckFREEPXD;
+				PXDaddress(&pxdlock->pxd, xaddr);
+				PXDlength(&pxdlock->pxd, freexlen);
+				txFreeMap(ip, pxdlock, NULL, COMMIT_WMAP);
+
+				/* reset map lock */
+				xadlock.flag = mlckFREEXADLIST;
+			}
+
+			/* current entry is new last entry; */
+			nextindex = index + 1;
+
+			nfreed += freexlen;
+		}
+		/*
+		 * eof beyond the entry:
+		 *          xad
+		 * -------=======---|--->
+		 *                 eof
+		 */
+		else {		/* (xoff + xlen < teof) */
+
+			nextindex = index + 1;
+		}
+
+		if (nextindex < le16_to_cpu(p->header.nextindex)) {
+			if (!log) {	/* COMMIT_WAMP */
+				xadlock.xdlist = &p->xad[nextindex];
+				xadlock.count =
+				    le16_to_cpu(p->header.nextindex) -
+				    nextindex;
+				txFreeMap(ip, (struct maplock *) & xadlock,
+					  NULL, COMMIT_WMAP);
+			}
+			p->header.nextindex = cpu_to_le16(nextindex);
+		}
+
+		XT_PUTPAGE(mp);
+
+		/* assert(freed == 0); */
+		goto getParent;
+	}			/* end scan of leaf page entries */
+
+	freed = 1;
+
+	/*
+	 * leaf page become empty: free the page if type != PMAP
+	 */
+	if (log) {		/* COMMIT_PWMAP */
+		/* txCommit() with tlckFREE:
+		 * free data extents covered by leaf [XTENTRYSTART:hwm);
+		 * invalidate leaf if COMMIT_PWMAP;
+		 * if (TRUNCATE), will write LOG_NOREDOPAGE;
+		 */
+		tlck->type = tlckXTREE | tlckFREE;
+	} else {		/* COMMIT_WAMP */
+
+		/* free data extents covered by leaf */
+		xadlock.xdlist = &p->xad[XTENTRYSTART];
+		xadlock.count =
+		    le16_to_cpu(p->header.nextindex) - XTENTRYSTART;
+		txFreeMap(ip, (struct maplock *) & xadlock, NULL, COMMIT_WMAP);
+	}
+
+	if (p->header.flag & BT_ROOT) {
+		p->header.flag &= ~BT_INTERNAL;
+		p->header.flag |= BT_LEAF;
+		p->header.nextindex = cpu_to_le16(XTENTRYSTART);
+
+		XT_PUTPAGE(mp);	/* debug */
+		goto out;
+	} else {
+		if (log) {	/* COMMIT_PWMAP */
+			/* page will be invalidated at tx completion
+			 */
+			XT_PUTPAGE(mp);
+		} else {	/* COMMIT_WMAP */
+
+			if (mp->lid)
+				lid_to_tlock(mp->lid)->flag |= tlckFREELOCK;
+
+			/* invalidate empty leaf page */
+			discard_metapage(mp);
+		}
+	}
+
+	/*
+	 * the leaf page become empty: delete the parent entry
+	 * for the leaf page if the parent page is to be kept
+	 * in the new sized file.
+	 */
+
+	/*
+	 * go back up to the parent page
+	 */
+      getParent:
+	/* pop/restore parent entry for the current child page */
+	if ((parent = BT_POP(&btstack)) == NULL)
+		/* current page must have been root */
+		goto out;
+
+	/* get back the parent page */
+	bn = parent->bn;
+	XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+	if (rc)
+		return rc;
+
+	index = parent->index;
+
+	/*
+	 * child page was not empty:
+	 */
+	if (freed == 0) {
+		/* has any entry deleted from parent ? */
+		if (index < le16_to_cpu(p->header.nextindex) - 1) {
+			/* (re)acquire tlock on the parent page */
+			if (log) {	/* COMMIT_PWMAP */
+				/* txCommit() with tlckTRUNCATE:
+				 * free child extents covered by parent [);
+				 */
+				tlck = txLock(tid, ip, mp, tlckXTREE);
+				xtlck = (struct xtlock *) & tlck->lock;
+				if (!(tlck->type & tlckTRUNCATE)) {
+					xtlck->hwm.offset =
+					    le16_to_cpu(p->header.
+							nextindex) - 1;
+					tlck->type =
+					    tlckXTREE | tlckTRUNCATE;
+				}
+			} else {	/* COMMIT_WMAP */
+
+				/* free child extents covered by parent */
+				xadlock.xdlist = &p->xad[index + 1];
+				xadlock.count =
+				    le16_to_cpu(p->header.nextindex) -
+				    index - 1;
+				txFreeMap(ip, (struct maplock *) & xadlock,
+					  NULL, COMMIT_WMAP);
+			}
+			BT_MARK_DIRTY(mp, ip);
+
+			p->header.nextindex = cpu_to_le16(index + 1);
+		}
+		XT_PUTPAGE(mp);
+		goto getParent;
+	}
+
+	/*
+	 * child page was empty:
+	 */
+	nfreed += lengthXAD(&p->xad[index]);
+
+	/*
+	 * During working map update, child page's tlock must be handled
+	 * before parent's.  This is because the parent's tlock will cause
+	 * the child's disk space to be marked available in the wmap, so
+	 * it's important that the child page be released by that time.
+	 *
+	 * ToDo:  tlocks should be on doubly-linked list, so we can
+	 * quickly remove it and add it to the end.
+	 */
+
+	/*
+	 * Move parent page's tlock to the end of the tid's tlock list
+	 */
+	if (log && mp->lid && (tblk->last != mp->lid) &&
+	    lid_to_tlock(mp->lid)->tid) {
+		lid_t lid = mp->lid;
+		struct tlock *prev;
+
+		tlck = lid_to_tlock(lid);
+
+		if (tblk->next == lid)
+			tblk->next = tlck->next;
+		else {
+			for (prev = lid_to_tlock(tblk->next);
+			     prev->next != lid;
+			     prev = lid_to_tlock(prev->next)) {
+				assert(prev->next);
+			}
+			prev->next = tlck->next;
+		}
+		lid_to_tlock(tblk->last)->next = lid;
+		tlck->next = 0;
+		tblk->last = lid;
+	}
+
+	/*
+	 * parent page become empty: free the page
+	 */
+	if (index == XTENTRYSTART) {
+		if (log) {	/* COMMIT_PWMAP */
+			/* txCommit() with tlckFREE:
+			 * free child extents covered by parent;
+			 * invalidate parent if COMMIT_PWMAP;
+			 */
+			tlck = txLock(tid, ip, mp, tlckXTREE);
+			xtlck = (struct xtlock *) & tlck->lock;
+			xtlck->hwm.offset =
+			    le16_to_cpu(p->header.nextindex) - 1;
+			tlck->type = tlckXTREE | tlckFREE;
+		} else {	/* COMMIT_WMAP */
+
+			/* free child extents covered by parent */
+			xadlock.xdlist = &p->xad[XTENTRYSTART];
+			xadlock.count =
+			    le16_to_cpu(p->header.nextindex) -
+			    XTENTRYSTART;
+			txFreeMap(ip, (struct maplock *) & xadlock, NULL,
+				  COMMIT_WMAP);
+		}
+		BT_MARK_DIRTY(mp, ip);
+
+		if (p->header.flag & BT_ROOT) {
+			p->header.flag &= ~BT_INTERNAL;
+			p->header.flag |= BT_LEAF;
+			p->header.nextindex = cpu_to_le16(XTENTRYSTART);
+			if (le16_to_cpu(p->header.maxentry) == XTROOTMAXSLOT) {
+				/*
+				 * Shrink root down to allow inline
+				 * EA (otherwise fsck complains)
+				 */
+				p->header.maxentry =
+				    cpu_to_le16(XTROOTINITSLOT);
+				JFS_IP(ip)->mode2 |= INLINEEA;
+			}
+
+			XT_PUTPAGE(mp);	/* debug */
+			goto out;
+		} else {
+			if (log) {	/* COMMIT_PWMAP */
+				/* page will be invalidated at tx completion
+				 */
+				XT_PUTPAGE(mp);
+			} else {	/* COMMIT_WMAP */
+
+				if (mp->lid)
+					lid_to_tlock(mp->lid)->flag |=
+						tlckFREELOCK;
+
+				/* invalidate parent page */
+				discard_metapage(mp);
+			}
+
+			/* parent has become empty and freed:
+			 * go back up to its parent page
+			 */
+			/* freed = 1; */
+			goto getParent;
+		}
+	}
+	/*
+	 * parent page still has entries for front region;
+	 */
+	else {
+		/* try truncate region covered by preceding entry
+		 * (process backward)
+		 */
+		index--;
+
+		/* go back down to the child page corresponding
+		 * to the entry
+		 */
+		goto getChild;
+	}
+
+	/*
+	 *	internal page: go down to child page of current entry
+	 */
+      getChild:
+	/* save current parent entry for the child page */
+	if (BT_STACK_FULL(&btstack)) {
+		jfs_error(ip->i_sb, "stack overrun!\n");
+		XT_PUTPAGE(mp);
+		return -EIO;
+	}
+	BT_PUSH(&btstack, bn, index);
+
+	/* get child page */
+	xad = &p->xad[index];
+	bn = addressXAD(xad);
+
+	/*
+	 * first access of each internal entry:
+	 */
+	/* release parent page */
+	XT_PUTPAGE(mp);
+
+	/* process the child page */
+	goto getPage;
+
+      out:
+	/*
+	 * update file resource stat
+	 */
+	/* set size
+	 */
+	if (S_ISDIR(ip->i_mode) && !newsize)
+		ip->i_size = 1;	/* fsck hates zero-length directories */
+	else
+		ip->i_size = newsize;
+
+	/* update quota allocation to reflect freed blocks */
+	dquot_free_block(ip, nfreed);
+
+	/*
+	 * free tlock of invalidated pages
+	 */
+	if (flag == COMMIT_WMAP)
+		txFreelock(ip);
+
+	return newsize;
+}
+
+
+/*
+ *	xtTruncate_pmap()
+ *
+ * function:
+ *	Perform truncate to zero length for deleted file, leaving the
+ *	xtree and working map untouched.  This allows the file to
+ *	be accessed via open file handles, while the delete of the file
+ *	is committed to disk.
+ *
+ * parameter:
+ *	tid_t		tid,
+ *	struct inode	*ip,
+ *	s64		committed_size)
+ *
+ * return: new committed size
+ *
+ * note:
+ *
+ *	To avoid deadlock by holding too many transaction locks, the
+ *	truncation may be broken up into multiple transactions.
+ *	The committed_size keeps track of part of the file has been
+ *	freed from the pmaps.
+ */
+s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size)
+{
+	s64 bn;
+	struct btstack btstack;
+	int cmp;
+	int index;
+	int locked_leaves = 0;
+	struct metapage *mp;
+	xtpage_t *p;
+	struct btframe *parent;
+	int rc;
+	struct tblock *tblk;
+	struct tlock *tlck = NULL;
+	xad_t *xad;
+	int xlen;
+	s64 xoff;
+	struct xtlock *xtlck = NULL;
+
+	/* save object truncation type */
+	tblk = tid_to_tblock(tid);
+	tblk->xflag |= COMMIT_PMAP;
+
+	/* clear stack */
+	BT_CLR(&btstack);
+
+	if (committed_size) {
+		xoff = (committed_size >> JFS_SBI(ip->i_sb)->l2bsize) - 1;
+		rc = xtSearch(ip, xoff, NULL, &cmp, &btstack, 0);
+		if (rc)
+			return rc;
+
+		XT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+		if (cmp != 0) {
+			XT_PUTPAGE(mp);
+			jfs_error(ip->i_sb, "did not find extent\n");
+			return -EIO;
+		}
+	} else {
+		/*
+		 * start with root
+		 *
+		 * root resides in the inode
+		 */
+		bn = 0;
+
+		/*
+		 * first access of each page:
+		 */
+      getPage:
+		XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+		if (rc)
+			return rc;
+
+		/* process entries backward from last index */
+		index = le16_to_cpu(p->header.nextindex) - 1;
+
+		if (p->header.flag & BT_INTERNAL)
+			goto getChild;
+	}
+
+	/*
+	 *	leaf page
+	 */
+
+	if (++locked_leaves > MAX_TRUNCATE_LEAVES) {
+		/*
+		 * We need to limit the size of the transaction
+		 * to avoid exhausting pagecache & tlocks
+		 */
+		xad = &p->xad[index];
+		xoff = offsetXAD(xad);
+		xlen = lengthXAD(xad);
+		XT_PUTPAGE(mp);
+		return (xoff + xlen) << JFS_SBI(ip->i_sb)->l2bsize;
+	}
+	tlck = txLock(tid, ip, mp, tlckXTREE);
+	tlck->type = tlckXTREE | tlckFREE;
+	xtlck = (struct xtlock *) & tlck->lock;
+	xtlck->hwm.offset = index;
+
+
+	XT_PUTPAGE(mp);
+
+	/*
+	 * go back up to the parent page
+	 */
+      getParent:
+	/* pop/restore parent entry for the current child page */
+	if ((parent = BT_POP(&btstack)) == NULL)
+		/* current page must have been root */
+		goto out;
+
+	/* get back the parent page */
+	bn = parent->bn;
+	XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+	if (rc)
+		return rc;
+
+	index = parent->index;
+
+	/*
+	 * parent page become empty: free the page
+	 */
+	if (index == XTENTRYSTART) {
+		/* txCommit() with tlckFREE:
+		 * free child extents covered by parent;
+		 * invalidate parent if COMMIT_PWMAP;
+		 */
+		tlck = txLock(tid, ip, mp, tlckXTREE);
+		xtlck = (struct xtlock *) & tlck->lock;
+		xtlck->hwm.offset = le16_to_cpu(p->header.nextindex) - 1;
+		tlck->type = tlckXTREE | tlckFREE;
+
+		XT_PUTPAGE(mp);
+
+		if (p->header.flag & BT_ROOT) {
+
+			goto out;
+		} else {
+			goto getParent;
+		}
+	}
+	/*
+	 * parent page still has entries for front region;
+	 */
+	else
+		index--;
+	/*
+	 *	internal page: go down to child page of current entry
+	 */
+      getChild:
+	/* save current parent entry for the child page */
+	if (BT_STACK_FULL(&btstack)) {
+		jfs_error(ip->i_sb, "stack overrun!\n");
+		XT_PUTPAGE(mp);
+		return -EIO;
+	}
+	BT_PUSH(&btstack, bn, index);
+
+	/* get child page */
+	xad = &p->xad[index];
+	bn = addressXAD(xad);
+
+	/*
+	 * first access of each internal entry:
+	 */
+	/* release parent page */
+	XT_PUTPAGE(mp);
+
+	/* process the child page */
+	goto getPage;
+
+      out:
+
+	return 0;
+}
+
+#ifdef CONFIG_JFS_STATISTICS
+int jfs_xtstat_proc_show(struct seq_file *m, void *v)
+{
+	seq_printf(m,
+		       "JFS Xtree statistics\n"
+		       "====================\n"
+		       "searches = %d\n"
+		       "fast searches = %d\n"
+		       "splits = %d\n",
+		       xtStat.search,
+		       xtStat.fastSearch,
+		       xtStat.split);
+	return 0;
+}
+#endif
diff --git a/fs/jfs/jfs_xtree.h b/fs/jfs/jfs_xtree.h
new file mode 100644
index 000000000..142caafc7
--- /dev/null
+++ b/fs/jfs/jfs_xtree.h
@@ -0,0 +1,108 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2002
+ */
+#ifndef _H_JFS_XTREE
+#define _H_JFS_XTREE
+
+/*
+ *	jfs_xtree.h: extent allocation descriptor B+-tree manager
+ */
+
+#include "jfs_btree.h"
+
+
+/*
+ *	extent allocation descriptor (xad)
+ */
+typedef struct xad {
+	__u8 flag;	/* 1: flag */
+	__u8 rsvrd[2];	/* 2: reserved */
+	__u8 off1;	/* 1: offset in unit of fsblksize */
+	__le32 off2;	/* 4: offset in unit of fsblksize */
+	pxd_t loc;	/* 8: length and address in unit of fsblksize */
+} xad_t;			/* (16) */
+
+#define MAXXLEN		((1 << 24) - 1)
+
+#define XTSLOTSIZE	16
+#define L2XTSLOTSIZE	4
+
+/* xad_t field construction */
+#define XADoffset(xad, offset64)\
+{\
+	(xad)->off1 = ((u64)offset64) >> 32;\
+	(xad)->off2 = __cpu_to_le32((offset64) & 0xffffffff);\
+}
+#define XADaddress(xad, address64) PXDaddress(&(xad)->loc, address64)
+#define XADlength(xad, length32) PXDlength(&(xad)->loc, length32)
+
+/* xad_t field extraction */
+#define offsetXAD(xad)\
+	( ((s64)((xad)->off1)) << 32 | __le32_to_cpu((xad)->off2))
+#define addressXAD(xad) addressPXD(&(xad)->loc)
+#define lengthXAD(xad) lengthPXD(&(xad)->loc)
+
+/* xad list */
+struct xadlist {
+	s16 maxnxad;
+	s16 nxad;
+	xad_t *xad;
+};
+
+/* xad_t flags */
+#define XAD_NEW		0x01	/* new */
+#define XAD_EXTENDED	0x02	/* extended */
+#define XAD_COMPRESSED	0x04	/* compressed with recorded length */
+#define XAD_NOTRECORDED 0x08	/* allocated but not recorded */
+#define XAD_COW		0x10	/* copy-on-write */
+
+
+/* possible values for maxentry */
+#define XTROOTINITSLOT_DIR 6
+#define XTROOTINITSLOT	10
+#define XTROOTMAXSLOT	18
+#define XTPAGEMAXSLOT	256
+#define XTENTRYSTART	2
+
+/*
+ *	xtree page:
+ */
+typedef union {
+	struct xtheader {
+		__le64 next;	/* 8: */
+		__le64 prev;	/* 8: */
+
+		u8 flag;	/* 1: */
+		u8 rsrvd1;	/* 1: */
+		__le16 nextindex;	/* 2: next index = number of entries */
+		__le16 maxentry;	/* 2: max number of entries */
+		__le16 rsrvd2;	/* 2: */
+
+		pxd_t self;	/* 8: self */
+	} header;		/* (32) */
+
+	xad_t xad[XTROOTMAXSLOT];	/* 16 * maxentry: xad array */
+} xtpage_t;
+
+/*
+ *	external declaration
+ */
+extern int xtLookup(struct inode *ip, s64 lstart, s64 llen,
+		    int *pflag, s64 * paddr, int *plen, int flag);
+extern void xtInitRoot(tid_t tid, struct inode *ip);
+extern int xtInsert(tid_t tid, struct inode *ip,
+		    int xflag, s64 xoff, int xlen, s64 * xaddrp, int flag);
+extern int xtExtend(tid_t tid, struct inode *ip, s64 xoff, int xlen,
+		    int flag);
+extern int xtUpdate(tid_t tid, struct inode *ip, struct xad *nxad);
+extern int xtDelete(tid_t tid, struct inode *ip, s64 xoff, int xlen,
+		    int flag);
+extern s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int type);
+extern s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size);
+extern int xtRelocate(tid_t tid, struct inode *ip,
+		      xad_t * oxad, s64 nxaddr, int xtype);
+extern int xtAppend(tid_t tid,
+		    struct inode *ip, int xflag, s64 xoff, int maxblocks,
+		    int *xlenp, s64 * xaddrp, int flag);
+#endif				/* !_H_JFS_XTREE */
diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c
new file mode 100644
index 000000000..b3a0fe064
--- /dev/null
+++ b/fs/jfs/namei.c
@@ -0,0 +1,1613 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+#include <linux/fs.h>
+#include <linux/namei.h>
+#include <linux/ctype.h>
+#include <linux/quotaops.h>
+#include <linux/exportfs.h>
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_inode.h"
+#include "jfs_dinode.h"
+#include "jfs_dmap.h"
+#include "jfs_unicode.h"
+#include "jfs_metapage.h"
+#include "jfs_xattr.h"
+#include "jfs_acl.h"
+#include "jfs_debug.h"
+
+/*
+ * forward references
+ */
+const struct dentry_operations jfs_ci_dentry_operations;
+
+static s64 commitZeroLink(tid_t, struct inode *);
+
+/*
+ * NAME:	free_ea_wmap(inode)
+ *
+ * FUNCTION:	free uncommitted extended attributes from working map
+ *
+ */
+static inline void free_ea_wmap(struct inode *inode)
+{
+	dxd_t *ea = &JFS_IP(inode)->ea;
+
+	if (ea->flag & DXD_EXTENT) {
+		/* free EA pages from cache */
+		invalidate_dxd_metapages(inode, *ea);
+		dbFree(inode, addressDXD(ea), lengthDXD(ea));
+	}
+	ea->flag = 0;
+}
+
+/*
+ * NAME:	jfs_create(dip, dentry, mode)
+ *
+ * FUNCTION:	create a regular file in the parent directory <dip>
+ *		with name = <from dentry> and mode = <mode>
+ *
+ * PARAMETER:	dip	- parent directory vnode
+ *		dentry	- dentry of new file
+ *		mode	- create mode (rwxrwxrwx).
+ *		nd- nd struct
+ *
+ * RETURN:	Errors from subroutines
+ *
+ */
+static int jfs_create(struct user_namespace *mnt_userns, struct inode *dip,
+		      struct dentry *dentry, umode_t mode, bool excl)
+{
+	int rc = 0;
+	tid_t tid;		/* transaction id */
+	struct inode *ip = NULL;	/* child directory inode */
+	ino_t ino;
+	struct component_name dname;	/* child directory name */
+	struct btstack btstack;
+	struct inode *iplist[2];
+	struct tblock *tblk;
+
+	jfs_info("jfs_create: dip:0x%p name:%pd", dip, dentry);
+
+	rc = dquot_initialize(dip);
+	if (rc)
+		goto out1;
+
+	/*
+	 * search parent directory for entry/freespace
+	 * (dtSearch() returns parent directory page pinned)
+	 */
+	if ((rc = get_UCSname(&dname, dentry)))
+		goto out1;
+
+	/*
+	 * Either iAlloc() or txBegin() may block.  Deadlock can occur if we
+	 * block there while holding dtree page, so we allocate the inode &
+	 * begin the transaction before we search the directory.
+	 */
+	ip = ialloc(dip, mode);
+	if (IS_ERR(ip)) {
+		rc = PTR_ERR(ip);
+		goto out2;
+	}
+
+	tid = txBegin(dip->i_sb, 0);
+
+	mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
+	mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
+
+	rc = jfs_init_acl(tid, ip, dip);
+	if (rc)
+		goto out3;
+
+	rc = jfs_init_security(tid, ip, dip, &dentry->d_name);
+	if (rc) {
+		txAbort(tid, 0);
+		goto out3;
+	}
+
+	if ((rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE))) {
+		jfs_err("jfs_create: dtSearch returned %d", rc);
+		txAbort(tid, 0);
+		goto out3;
+	}
+
+	tblk = tid_to_tblock(tid);
+	tblk->xflag |= COMMIT_CREATE;
+	tblk->ino = ip->i_ino;
+	tblk->u.ixpxd = JFS_IP(ip)->ixpxd;
+
+	iplist[0] = dip;
+	iplist[1] = ip;
+
+	/*
+	 * initialize the child XAD tree root in-line in inode
+	 */
+	xtInitRoot(tid, ip);
+
+	/*
+	 * create entry in parent directory for child directory
+	 * (dtInsert() releases parent directory page)
+	 */
+	ino = ip->i_ino;
+	if ((rc = dtInsert(tid, dip, &dname, &ino, &btstack))) {
+		if (rc == -EIO) {
+			jfs_err("jfs_create: dtInsert returned -EIO");
+			txAbort(tid, 1);	/* Marks Filesystem dirty */
+		} else
+			txAbort(tid, 0);	/* Filesystem full */
+		goto out3;
+	}
+
+	ip->i_op = &jfs_file_inode_operations;
+	ip->i_fop = &jfs_file_operations;
+	ip->i_mapping->a_ops = &jfs_aops;
+
+	mark_inode_dirty(ip);
+
+	dip->i_ctime = dip->i_mtime = current_time(dip);
+
+	mark_inode_dirty(dip);
+
+	rc = txCommit(tid, 2, &iplist[0], 0);
+
+      out3:
+	txEnd(tid);
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	mutex_unlock(&JFS_IP(dip)->commit_mutex);
+	if (rc) {
+		free_ea_wmap(ip);
+		clear_nlink(ip);
+		discard_new_inode(ip);
+	} else {
+		d_instantiate_new(dentry, ip);
+	}
+
+      out2:
+	free_UCSname(&dname);
+
+      out1:
+
+	jfs_info("jfs_create: rc:%d", rc);
+	return rc;
+}
+
+
+/*
+ * NAME:	jfs_mkdir(dip, dentry, mode)
+ *
+ * FUNCTION:	create a child directory in the parent directory <dip>
+ *		with name = <from dentry> and mode = <mode>
+ *
+ * PARAMETER:	dip	- parent directory vnode
+ *		dentry	- dentry of child directory
+ *		mode	- create mode (rwxrwxrwx).
+ *
+ * RETURN:	Errors from subroutines
+ *
+ * note:
+ * EACCES: user needs search+write permission on the parent directory
+ */
+static int jfs_mkdir(struct user_namespace *mnt_userns, struct inode *dip,
+		     struct dentry *dentry, umode_t mode)
+{
+	int rc = 0;
+	tid_t tid;		/* transaction id */
+	struct inode *ip = NULL;	/* child directory inode */
+	ino_t ino;
+	struct component_name dname;	/* child directory name */
+	struct btstack btstack;
+	struct inode *iplist[2];
+	struct tblock *tblk;
+
+	jfs_info("jfs_mkdir: dip:0x%p name:%pd", dip, dentry);
+
+	rc = dquot_initialize(dip);
+	if (rc)
+		goto out1;
+
+	/*
+	 * search parent directory for entry/freespace
+	 * (dtSearch() returns parent directory page pinned)
+	 */
+	if ((rc = get_UCSname(&dname, dentry)))
+		goto out1;
+
+	/*
+	 * Either iAlloc() or txBegin() may block.  Deadlock can occur if we
+	 * block there while holding dtree page, so we allocate the inode &
+	 * begin the transaction before we search the directory.
+	 */
+	ip = ialloc(dip, S_IFDIR | mode);
+	if (IS_ERR(ip)) {
+		rc = PTR_ERR(ip);
+		goto out2;
+	}
+
+	tid = txBegin(dip->i_sb, 0);
+
+	mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
+	mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
+
+	rc = jfs_init_acl(tid, ip, dip);
+	if (rc)
+		goto out3;
+
+	rc = jfs_init_security(tid, ip, dip, &dentry->d_name);
+	if (rc) {
+		txAbort(tid, 0);
+		goto out3;
+	}
+
+	if ((rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE))) {
+		jfs_err("jfs_mkdir: dtSearch returned %d", rc);
+		txAbort(tid, 0);
+		goto out3;
+	}
+
+	tblk = tid_to_tblock(tid);
+	tblk->xflag |= COMMIT_CREATE;
+	tblk->ino = ip->i_ino;
+	tblk->u.ixpxd = JFS_IP(ip)->ixpxd;
+
+	iplist[0] = dip;
+	iplist[1] = ip;
+
+	/*
+	 * initialize the child directory in-line in inode
+	 */
+	dtInitRoot(tid, ip, dip->i_ino);
+
+	/*
+	 * create entry in parent directory for child directory
+	 * (dtInsert() releases parent directory page)
+	 */
+	ino = ip->i_ino;
+	if ((rc = dtInsert(tid, dip, &dname, &ino, &btstack))) {
+		if (rc == -EIO) {
+			jfs_err("jfs_mkdir: dtInsert returned -EIO");
+			txAbort(tid, 1);	/* Marks Filesystem dirty */
+		} else
+			txAbort(tid, 0);	/* Filesystem full */
+		goto out3;
+	}
+
+	set_nlink(ip, 2);	/* for '.' */
+	ip->i_op = &jfs_dir_inode_operations;
+	ip->i_fop = &jfs_dir_operations;
+
+	mark_inode_dirty(ip);
+
+	/* update parent directory inode */
+	inc_nlink(dip);		/* for '..' from child directory */
+	dip->i_ctime = dip->i_mtime = current_time(dip);
+	mark_inode_dirty(dip);
+
+	rc = txCommit(tid, 2, &iplist[0], 0);
+
+      out3:
+	txEnd(tid);
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	mutex_unlock(&JFS_IP(dip)->commit_mutex);
+	if (rc) {
+		free_ea_wmap(ip);
+		clear_nlink(ip);
+		discard_new_inode(ip);
+	} else {
+		d_instantiate_new(dentry, ip);
+	}
+
+      out2:
+	free_UCSname(&dname);
+
+
+      out1:
+
+	jfs_info("jfs_mkdir: rc:%d", rc);
+	return rc;
+}
+
+/*
+ * NAME:	jfs_rmdir(dip, dentry)
+ *
+ * FUNCTION:	remove a link to child directory
+ *
+ * PARAMETER:	dip	- parent inode
+ *		dentry	- child directory dentry
+ *
+ * RETURN:	-EINVAL	- if name is . or ..
+ *		-EINVAL - if . or .. exist but are invalid.
+ *		errors from subroutines
+ *
+ * note:
+ * if other threads have the directory open when the last link
+ * is removed, the "." and ".." entries, if present, are removed before
+ * rmdir() returns and no new entries may be created in the directory,
+ * but the directory is not removed until the last reference to
+ * the directory is released (cf.unlink() of regular file).
+ */
+static int jfs_rmdir(struct inode *dip, struct dentry *dentry)
+{
+	int rc;
+	tid_t tid;		/* transaction id */
+	struct inode *ip = d_inode(dentry);
+	ino_t ino;
+	struct component_name dname;
+	struct inode *iplist[2];
+	struct tblock *tblk;
+
+	jfs_info("jfs_rmdir: dip:0x%p name:%pd", dip, dentry);
+
+	/* Init inode for quota operations. */
+	rc = dquot_initialize(dip);
+	if (rc)
+		goto out;
+	rc = dquot_initialize(ip);
+	if (rc)
+		goto out;
+
+	/* directory must be empty to be removed */
+	if (!dtEmpty(ip)) {
+		rc = -ENOTEMPTY;
+		goto out;
+	}
+
+	if ((rc = get_UCSname(&dname, dentry))) {
+		goto out;
+	}
+
+	tid = txBegin(dip->i_sb, 0);
+
+	mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
+	mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
+
+	iplist[0] = dip;
+	iplist[1] = ip;
+
+	tblk = tid_to_tblock(tid);
+	tblk->xflag |= COMMIT_DELETE;
+	tblk->u.ip = ip;
+
+	/*
+	 * delete the entry of target directory from parent directory
+	 */
+	ino = ip->i_ino;
+	if ((rc = dtDelete(tid, dip, &dname, &ino, JFS_REMOVE))) {
+		jfs_err("jfs_rmdir: dtDelete returned %d", rc);
+		if (rc == -EIO)
+			txAbort(tid, 1);
+		txEnd(tid);
+		mutex_unlock(&JFS_IP(ip)->commit_mutex);
+		mutex_unlock(&JFS_IP(dip)->commit_mutex);
+
+		goto out2;
+	}
+
+	/* update parent directory's link count corresponding
+	 * to ".." entry of the target directory deleted
+	 */
+	dip->i_ctime = dip->i_mtime = current_time(dip);
+	inode_dec_link_count(dip);
+
+	/*
+	 * OS/2 could have created EA and/or ACL
+	 */
+	/* free EA from both persistent and working map */
+	if (JFS_IP(ip)->ea.flag & DXD_EXTENT) {
+		/* free EA pages */
+		txEA(tid, ip, &JFS_IP(ip)->ea, NULL);
+	}
+	JFS_IP(ip)->ea.flag = 0;
+
+	/* free ACL from both persistent and working map */
+	if (JFS_IP(ip)->acl.flag & DXD_EXTENT) {
+		/* free ACL pages */
+		txEA(tid, ip, &JFS_IP(ip)->acl, NULL);
+	}
+	JFS_IP(ip)->acl.flag = 0;
+
+	/* mark the target directory as deleted */
+	clear_nlink(ip);
+	mark_inode_dirty(ip);
+
+	rc = txCommit(tid, 2, &iplist[0], 0);
+
+	txEnd(tid);
+
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	mutex_unlock(&JFS_IP(dip)->commit_mutex);
+
+	/*
+	 * Truncating the directory index table is not guaranteed.  It
+	 * may need to be done iteratively
+	 */
+	if (test_cflag(COMMIT_Stale, dip)) {
+		if (dip->i_size > 1)
+			jfs_truncate_nolock(dip, 0);
+
+		clear_cflag(COMMIT_Stale, dip);
+	}
+
+      out2:
+	free_UCSname(&dname);
+
+      out:
+	jfs_info("jfs_rmdir: rc:%d", rc);
+	return rc;
+}
+
+/*
+ * NAME:	jfs_unlink(dip, dentry)
+ *
+ * FUNCTION:	remove a link to object <vp> named by <name>
+ *		from parent directory <dvp>
+ *
+ * PARAMETER:	dip	- inode of parent directory
+ *		dentry	- dentry of object to be removed
+ *
+ * RETURN:	errors from subroutines
+ *
+ * note:
+ * temporary file: if one or more processes have the file open
+ * when the last link is removed, the link will be removed before
+ * unlink() returns, but the removal of the file contents will be
+ * postponed until all references to the files are closed.
+ *
+ * JFS does NOT support unlink() on directories.
+ *
+ */
+static int jfs_unlink(struct inode *dip, struct dentry *dentry)
+{
+	int rc;
+	tid_t tid;		/* transaction id */
+	struct inode *ip = d_inode(dentry);
+	ino_t ino;
+	struct component_name dname;	/* object name */
+	struct inode *iplist[2];
+	struct tblock *tblk;
+	s64 new_size = 0;
+	int commit_flag;
+
+	jfs_info("jfs_unlink: dip:0x%p name:%pd", dip, dentry);
+
+	/* Init inode for quota operations. */
+	rc = dquot_initialize(dip);
+	if (rc)
+		goto out;
+	rc = dquot_initialize(ip);
+	if (rc)
+		goto out;
+
+	if ((rc = get_UCSname(&dname, dentry)))
+		goto out;
+
+	IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
+
+	tid = txBegin(dip->i_sb, 0);
+
+	mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
+	mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
+
+	iplist[0] = dip;
+	iplist[1] = ip;
+
+	/*
+	 * delete the entry of target file from parent directory
+	 */
+	ino = ip->i_ino;
+	if ((rc = dtDelete(tid, dip, &dname, &ino, JFS_REMOVE))) {
+		jfs_err("jfs_unlink: dtDelete returned %d", rc);
+		if (rc == -EIO)
+			txAbort(tid, 1);	/* Marks FS Dirty */
+		txEnd(tid);
+		mutex_unlock(&JFS_IP(ip)->commit_mutex);
+		mutex_unlock(&JFS_IP(dip)->commit_mutex);
+		IWRITE_UNLOCK(ip);
+		goto out1;
+	}
+
+	ASSERT(ip->i_nlink);
+
+	ip->i_ctime = dip->i_ctime = dip->i_mtime = current_time(ip);
+	mark_inode_dirty(dip);
+
+	/* update target's inode */
+	inode_dec_link_count(ip);
+
+	/*
+	 *	commit zero link count object
+	 */
+	if (ip->i_nlink == 0) {
+		assert(!test_cflag(COMMIT_Nolink, ip));
+		/* free block resources */
+		if ((new_size = commitZeroLink(tid, ip)) < 0) {
+			txAbort(tid, 1);	/* Marks FS Dirty */
+			txEnd(tid);
+			mutex_unlock(&JFS_IP(ip)->commit_mutex);
+			mutex_unlock(&JFS_IP(dip)->commit_mutex);
+			IWRITE_UNLOCK(ip);
+			rc = new_size;
+			goto out1;
+		}
+		tblk = tid_to_tblock(tid);
+		tblk->xflag |= COMMIT_DELETE;
+		tblk->u.ip = ip;
+	}
+
+	/*
+	 * Incomplete truncate of file data can
+	 * result in timing problems unless we synchronously commit the
+	 * transaction.
+	 */
+	if (new_size)
+		commit_flag = COMMIT_SYNC;
+	else
+		commit_flag = 0;
+
+	/*
+	 * If xtTruncate was incomplete, commit synchronously to avoid
+	 * timing complications
+	 */
+	rc = txCommit(tid, 2, &iplist[0], commit_flag);
+
+	txEnd(tid);
+
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	mutex_unlock(&JFS_IP(dip)->commit_mutex);
+
+	while (new_size && (rc == 0)) {
+		tid = txBegin(dip->i_sb, 0);
+		mutex_lock(&JFS_IP(ip)->commit_mutex);
+		new_size = xtTruncate_pmap(tid, ip, new_size);
+		if (new_size < 0) {
+			txAbort(tid, 1);	/* Marks FS Dirty */
+			rc = new_size;
+		} else
+			rc = txCommit(tid, 2, &iplist[0], COMMIT_SYNC);
+		txEnd(tid);
+		mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	}
+
+	if (ip->i_nlink == 0)
+		set_cflag(COMMIT_Nolink, ip);
+
+	IWRITE_UNLOCK(ip);
+
+	/*
+	 * Truncating the directory index table is not guaranteed.  It
+	 * may need to be done iteratively
+	 */
+	if (test_cflag(COMMIT_Stale, dip)) {
+		if (dip->i_size > 1)
+			jfs_truncate_nolock(dip, 0);
+
+		clear_cflag(COMMIT_Stale, dip);
+	}
+
+      out1:
+	free_UCSname(&dname);
+      out:
+	jfs_info("jfs_unlink: rc:%d", rc);
+	return rc;
+}
+
+/*
+ * NAME:	commitZeroLink()
+ *
+ * FUNCTION:	for non-directory, called by jfs_remove(),
+ *		truncate a regular file, directory or symbolic
+ *		link to zero length. return 0 if type is not
+ *		one of these.
+ *
+ *		if the file is currently associated with a VM segment
+ *		only permanent disk and inode map resources are freed,
+ *		and neither the inode nor indirect blocks are modified
+ *		so that the resources can be later freed in the work
+ *		map by ctrunc1.
+ *		if there is no VM segment on entry, the resources are
+ *		freed in both work and permanent map.
+ *		(? for temporary file - memory object is cached even
+ *		after no reference:
+ *		reference count > 0 -   )
+ *
+ * PARAMETERS:	cd	- pointer to commit data structure.
+ *			  current inode is the one to truncate.
+ *
+ * RETURN:	Errors from subroutines
+ */
+static s64 commitZeroLink(tid_t tid, struct inode *ip)
+{
+	int filetype;
+	struct tblock *tblk;
+
+	jfs_info("commitZeroLink: tid = %d, ip = 0x%p", tid, ip);
+
+	filetype = ip->i_mode & S_IFMT;
+	switch (filetype) {
+	case S_IFREG:
+		break;
+	case S_IFLNK:
+		/* fast symbolic link */
+		if (ip->i_size < IDATASIZE) {
+			ip->i_size = 0;
+			return 0;
+		}
+		break;
+	default:
+		assert(filetype != S_IFDIR);
+		return 0;
+	}
+
+	set_cflag(COMMIT_Freewmap, ip);
+
+	/* mark transaction of block map update type */
+	tblk = tid_to_tblock(tid);
+	tblk->xflag |= COMMIT_PMAP;
+
+	/*
+	 * free EA
+	 */
+	if (JFS_IP(ip)->ea.flag & DXD_EXTENT)
+		/* acquire maplock on EA to be freed from block map */
+		txEA(tid, ip, &JFS_IP(ip)->ea, NULL);
+
+	/*
+	 * free ACL
+	 */
+	if (JFS_IP(ip)->acl.flag & DXD_EXTENT)
+		/* acquire maplock on EA to be freed from block map */
+		txEA(tid, ip, &JFS_IP(ip)->acl, NULL);
+
+	/*
+	 * free xtree/data (truncate to zero length):
+	 * free xtree/data pages from cache if COMMIT_PWMAP,
+	 * free xtree/data blocks from persistent block map, and
+	 * free xtree/data blocks from working block map if COMMIT_PWMAP;
+	 */
+	if (ip->i_size)
+		return xtTruncate_pmap(tid, ip, 0);
+
+	return 0;
+}
+
+
+/*
+ * NAME:	jfs_free_zero_link()
+ *
+ * FUNCTION:	for non-directory, called by iClose(),
+ *		free resources of a file from cache and WORKING map
+ *		for a file previously committed with zero link count
+ *		while associated with a pager object,
+ *
+ * PARAMETER:	ip	- pointer to inode of file.
+ */
+void jfs_free_zero_link(struct inode *ip)
+{
+	int type;
+
+	jfs_info("jfs_free_zero_link: ip = 0x%p", ip);
+
+	/* return if not reg or symbolic link or if size is
+	 * already ok.
+	 */
+	type = ip->i_mode & S_IFMT;
+
+	switch (type) {
+	case S_IFREG:
+		break;
+	case S_IFLNK:
+		/* if its contained in inode nothing to do */
+		if (ip->i_size < IDATASIZE)
+			return;
+		break;
+	default:
+		return;
+	}
+
+	/*
+	 * free EA
+	 */
+	if (JFS_IP(ip)->ea.flag & DXD_EXTENT) {
+		s64 xaddr = addressDXD(&JFS_IP(ip)->ea);
+		int xlen = lengthDXD(&JFS_IP(ip)->ea);
+		struct maplock maplock;	/* maplock for COMMIT_WMAP */
+		struct pxd_lock *pxdlock;	/* maplock for COMMIT_WMAP */
+
+		/* free EA pages from cache */
+		invalidate_dxd_metapages(ip, JFS_IP(ip)->ea);
+
+		/* free EA extent from working block map */
+		maplock.index = 1;
+		pxdlock = (struct pxd_lock *) & maplock;
+		pxdlock->flag = mlckFREEPXD;
+		PXDaddress(&pxdlock->pxd, xaddr);
+		PXDlength(&pxdlock->pxd, xlen);
+		txFreeMap(ip, pxdlock, NULL, COMMIT_WMAP);
+	}
+
+	/*
+	 * free ACL
+	 */
+	if (JFS_IP(ip)->acl.flag & DXD_EXTENT) {
+		s64 xaddr = addressDXD(&JFS_IP(ip)->acl);
+		int xlen = lengthDXD(&JFS_IP(ip)->acl);
+		struct maplock maplock;	/* maplock for COMMIT_WMAP */
+		struct pxd_lock *pxdlock;	/* maplock for COMMIT_WMAP */
+
+		invalidate_dxd_metapages(ip, JFS_IP(ip)->acl);
+
+		/* free ACL extent from working block map */
+		maplock.index = 1;
+		pxdlock = (struct pxd_lock *) & maplock;
+		pxdlock->flag = mlckFREEPXD;
+		PXDaddress(&pxdlock->pxd, xaddr);
+		PXDlength(&pxdlock->pxd, xlen);
+		txFreeMap(ip, pxdlock, NULL, COMMIT_WMAP);
+	}
+
+	/*
+	 * free xtree/data (truncate to zero length):
+	 * free xtree/data pages from cache, and
+	 * free xtree/data blocks from working block map;
+	 */
+	if (ip->i_size)
+		xtTruncate(0, ip, 0, COMMIT_WMAP);
+}
+
+/*
+ * NAME:	jfs_link(vp, dvp, name, crp)
+ *
+ * FUNCTION:	create a link to <vp> by the name = <name>
+ *		in the parent directory <dvp>
+ *
+ * PARAMETER:	vp	- target object
+ *		dvp	- parent directory of new link
+ *		name	- name of new link to target object
+ *		crp	- credential
+ *
+ * RETURN:	Errors from subroutines
+ *
+ * note:
+ * JFS does NOT support link() on directories (to prevent circular
+ * path in the directory hierarchy);
+ * EPERM: the target object is a directory, and either the caller
+ * does not have appropriate privileges or the implementation prohibits
+ * using link() on directories [XPG4.2].
+ *
+ * JFS does NOT support links between file systems:
+ * EXDEV: target object and new link are on different file systems and
+ * implementation does not support links between file systems [XPG4.2].
+ */
+static int jfs_link(struct dentry *old_dentry,
+	     struct inode *dir, struct dentry *dentry)
+{
+	int rc;
+	tid_t tid;
+	struct inode *ip = d_inode(old_dentry);
+	ino_t ino;
+	struct component_name dname;
+	struct btstack btstack;
+	struct inode *iplist[2];
+
+	jfs_info("jfs_link: %pd %pd", old_dentry, dentry);
+
+	rc = dquot_initialize(dir);
+	if (rc)
+		goto out;
+
+	if (isReadOnly(ip)) {
+		jfs_error(ip->i_sb, "read-only filesystem\n");
+		return -EROFS;
+	}
+
+	tid = txBegin(ip->i_sb, 0);
+
+	mutex_lock_nested(&JFS_IP(dir)->commit_mutex, COMMIT_MUTEX_PARENT);
+	mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
+
+	/*
+	 * scan parent directory for entry/freespace
+	 */
+	if ((rc = get_UCSname(&dname, dentry)))
+		goto out_tx;
+
+	if ((rc = dtSearch(dir, &dname, &ino, &btstack, JFS_CREATE)))
+		goto free_dname;
+
+	/*
+	 * create entry for new link in parent directory
+	 */
+	ino = ip->i_ino;
+	if ((rc = dtInsert(tid, dir, &dname, &ino, &btstack)))
+		goto free_dname;
+
+	/* update object inode */
+	inc_nlink(ip);		/* for new link */
+	ip->i_ctime = current_time(ip);
+	dir->i_ctime = dir->i_mtime = current_time(dir);
+	mark_inode_dirty(dir);
+	ihold(ip);
+
+	iplist[0] = ip;
+	iplist[1] = dir;
+	rc = txCommit(tid, 2, &iplist[0], 0);
+
+	if (rc) {
+		drop_nlink(ip); /* never instantiated */
+		iput(ip);
+	} else
+		d_instantiate(dentry, ip);
+
+      free_dname:
+	free_UCSname(&dname);
+
+      out_tx:
+	txEnd(tid);
+
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	mutex_unlock(&JFS_IP(dir)->commit_mutex);
+
+      out:
+	jfs_info("jfs_link: rc:%d", rc);
+	return rc;
+}
+
+/*
+ * NAME:	jfs_symlink(dip, dentry, name)
+ *
+ * FUNCTION:	creates a symbolic link to <symlink> by name <name>
+ *			in directory <dip>
+ *
+ * PARAMETER:	dip	- parent directory vnode
+ *		dentry	- dentry of symbolic link
+ *		name	- the path name of the existing object
+ *			  that will be the source of the link
+ *
+ * RETURN:	errors from subroutines
+ *
+ * note:
+ * ENAMETOOLONG: pathname resolution of a symbolic link produced
+ * an intermediate result whose length exceeds PATH_MAX [XPG4.2]
+*/
+
+static int jfs_symlink(struct user_namespace *mnt_userns, struct inode *dip,
+		       struct dentry *dentry, const char *name)
+{
+	int rc;
+	tid_t tid;
+	ino_t ino = 0;
+	struct component_name dname;
+	int ssize;		/* source pathname size */
+	struct btstack btstack;
+	struct inode *ip = d_inode(dentry);
+	s64 xlen = 0;
+	int bmask = 0, xsize;
+	s64 xaddr;
+	struct metapage *mp;
+	struct super_block *sb;
+	struct tblock *tblk;
+
+	struct inode *iplist[2];
+
+	jfs_info("jfs_symlink: dip:0x%p name:%s", dip, name);
+
+	rc = dquot_initialize(dip);
+	if (rc)
+		goto out1;
+
+	ssize = strlen(name) + 1;
+
+	/*
+	 * search parent directory for entry/freespace
+	 * (dtSearch() returns parent directory page pinned)
+	 */
+
+	if ((rc = get_UCSname(&dname, dentry)))
+		goto out1;
+
+	/*
+	 * allocate on-disk/in-memory inode for symbolic link:
+	 * (iAlloc() returns new, locked inode)
+	 */
+	ip = ialloc(dip, S_IFLNK | 0777);
+	if (IS_ERR(ip)) {
+		rc = PTR_ERR(ip);
+		goto out2;
+	}
+
+	tid = txBegin(dip->i_sb, 0);
+
+	mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
+	mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
+
+	rc = jfs_init_security(tid, ip, dip, &dentry->d_name);
+	if (rc)
+		goto out3;
+
+	tblk = tid_to_tblock(tid);
+	tblk->xflag |= COMMIT_CREATE;
+	tblk->ino = ip->i_ino;
+	tblk->u.ixpxd = JFS_IP(ip)->ixpxd;
+
+	/* fix symlink access permission
+	 * (dir_create() ANDs in the u.u_cmask,
+	 * but symlinks really need to be 777 access)
+	 */
+	ip->i_mode |= 0777;
+
+	/*
+	 * write symbolic link target path name
+	 */
+	xtInitRoot(tid, ip);
+
+	/*
+	 * write source path name inline in on-disk inode (fast symbolic link)
+	 */
+
+	if (ssize <= IDATASIZE) {
+		ip->i_op = &jfs_fast_symlink_inode_operations;
+
+		ip->i_link = JFS_IP(ip)->i_inline_all;
+		memcpy(ip->i_link, name, ssize);
+		ip->i_size = ssize - 1;
+
+		/*
+		 * if symlink is > 128 bytes, we don't have the space to
+		 * store inline extended attributes
+		 */
+		if (ssize > sizeof (JFS_IP(ip)->i_inline))
+			JFS_IP(ip)->mode2 &= ~INLINEEA;
+
+		jfs_info("jfs_symlink: fast symlink added  ssize:%d name:%s ",
+			 ssize, name);
+	}
+	/*
+	 * write source path name in a single extent
+	 */
+	else {
+		jfs_info("jfs_symlink: allocate extent ip:0x%p", ip);
+
+		ip->i_op = &jfs_symlink_inode_operations;
+		inode_nohighmem(ip);
+		ip->i_mapping->a_ops = &jfs_aops;
+
+		/*
+		 * even though the data of symlink object (source
+		 * path name) is treated as non-journaled user data,
+		 * it is read/written thru buffer cache for performance.
+		 */
+		sb = ip->i_sb;
+		bmask = JFS_SBI(sb)->bsize - 1;
+		xsize = (ssize + bmask) & ~bmask;
+		xaddr = 0;
+		xlen = xsize >> JFS_SBI(sb)->l2bsize;
+		if ((rc = xtInsert(tid, ip, 0, 0, xlen, &xaddr, 0))) {
+			txAbort(tid, 0);
+			goto out3;
+		}
+		ip->i_size = ssize - 1;
+		while (ssize) {
+			/* This is kind of silly since PATH_MAX == 4K */
+			int copy_size = min(ssize, PSIZE);
+
+			mp = get_metapage(ip, xaddr, PSIZE, 1);
+
+			if (mp == NULL) {
+				xtTruncate(tid, ip, 0, COMMIT_PWMAP);
+				rc = -EIO;
+				txAbort(tid, 0);
+				goto out3;
+			}
+			memcpy(mp->data, name, copy_size);
+			flush_metapage(mp);
+			ssize -= copy_size;
+			name += copy_size;
+			xaddr += JFS_SBI(sb)->nbperpage;
+		}
+	}
+
+	/*
+	 * create entry for symbolic link in parent directory
+	 */
+	rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE);
+	if (rc == 0) {
+		ino = ip->i_ino;
+		rc = dtInsert(tid, dip, &dname, &ino, &btstack);
+	}
+	if (rc) {
+		if (xlen)
+			xtTruncate(tid, ip, 0, COMMIT_PWMAP);
+		txAbort(tid, 0);
+		/* discard new inode */
+		goto out3;
+	}
+
+	mark_inode_dirty(ip);
+
+	dip->i_ctime = dip->i_mtime = current_time(dip);
+	mark_inode_dirty(dip);
+	/*
+	 * commit update of parent directory and link object
+	 */
+
+	iplist[0] = dip;
+	iplist[1] = ip;
+	rc = txCommit(tid, 2, &iplist[0], 0);
+
+      out3:
+	txEnd(tid);
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	mutex_unlock(&JFS_IP(dip)->commit_mutex);
+	if (rc) {
+		free_ea_wmap(ip);
+		clear_nlink(ip);
+		discard_new_inode(ip);
+	} else {
+		d_instantiate_new(dentry, ip);
+	}
+
+      out2:
+	free_UCSname(&dname);
+
+      out1:
+	jfs_info("jfs_symlink: rc:%d", rc);
+	return rc;
+}
+
+
+/*
+ * NAME:	jfs_rename
+ *
+ * FUNCTION:	rename a file or directory
+ */
+static int jfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		      struct dentry *old_dentry, struct inode *new_dir,
+		      struct dentry *new_dentry, unsigned int flags)
+{
+	struct btstack btstack;
+	ino_t ino;
+	struct component_name new_dname;
+	struct inode *new_ip;
+	struct component_name old_dname;
+	struct inode *old_ip;
+	int rc;
+	tid_t tid;
+	struct tlock *tlck;
+	struct dt_lock *dtlck;
+	struct lv *lv;
+	int ipcount;
+	struct inode *iplist[4];
+	struct tblock *tblk;
+	s64 new_size = 0;
+	int commit_flag;
+
+	if (flags & ~RENAME_NOREPLACE)
+		return -EINVAL;
+
+	jfs_info("jfs_rename: %pd %pd", old_dentry, new_dentry);
+
+	rc = dquot_initialize(old_dir);
+	if (rc)
+		goto out1;
+	rc = dquot_initialize(new_dir);
+	if (rc)
+		goto out1;
+
+	old_ip = d_inode(old_dentry);
+	new_ip = d_inode(new_dentry);
+
+	if ((rc = get_UCSname(&old_dname, old_dentry)))
+		goto out1;
+
+	if ((rc = get_UCSname(&new_dname, new_dentry)))
+		goto out2;
+
+	/*
+	 * Make sure source inode number is what we think it is
+	 */
+	rc = dtSearch(old_dir, &old_dname, &ino, &btstack, JFS_LOOKUP);
+	if (rc || (ino != old_ip->i_ino)) {
+		rc = -ENOENT;
+		goto out3;
+	}
+
+	/*
+	 * Make sure dest inode number (if any) is what we think it is
+	 */
+	rc = dtSearch(new_dir, &new_dname, &ino, &btstack, JFS_LOOKUP);
+	if (!rc) {
+		if ((!new_ip) || (ino != new_ip->i_ino)) {
+			rc = -ESTALE;
+			goto out3;
+		}
+	} else if (rc != -ENOENT)
+		goto out3;
+	else if (new_ip) {
+		/* no entry exists, but one was expected */
+		rc = -ESTALE;
+		goto out3;
+	}
+
+	if (S_ISDIR(old_ip->i_mode)) {
+		if (new_ip) {
+			if (!dtEmpty(new_ip)) {
+				rc = -ENOTEMPTY;
+				goto out3;
+			}
+		}
+	} else if (new_ip) {
+		IWRITE_LOCK(new_ip, RDWRLOCK_NORMAL);
+		/* Init inode for quota operations. */
+		rc = dquot_initialize(new_ip);
+		if (rc)
+			goto out_unlock;
+	}
+
+	/*
+	 * The real work starts here
+	 */
+	tid = txBegin(new_dir->i_sb, 0);
+
+	/*
+	 * How do we know the locking is safe from deadlocks?
+	 * The vfs does the hard part for us.  Any time we are taking nested
+	 * commit_mutexes, the vfs already has i_mutex held on the parent.
+	 * Here, the vfs has already taken i_mutex on both old_dir and new_dir.
+	 */
+	mutex_lock_nested(&JFS_IP(new_dir)->commit_mutex, COMMIT_MUTEX_PARENT);
+	mutex_lock_nested(&JFS_IP(old_ip)->commit_mutex, COMMIT_MUTEX_CHILD);
+	if (old_dir != new_dir)
+		mutex_lock_nested(&JFS_IP(old_dir)->commit_mutex,
+				  COMMIT_MUTEX_SECOND_PARENT);
+
+	if (new_ip) {
+		mutex_lock_nested(&JFS_IP(new_ip)->commit_mutex,
+				  COMMIT_MUTEX_VICTIM);
+		/*
+		 * Change existing directory entry to new inode number
+		 */
+		ino = new_ip->i_ino;
+		rc = dtModify(tid, new_dir, &new_dname, &ino,
+			      old_ip->i_ino, JFS_RENAME);
+		if (rc)
+			goto out_tx;
+		drop_nlink(new_ip);
+		if (S_ISDIR(new_ip->i_mode)) {
+			drop_nlink(new_ip);
+			if (new_ip->i_nlink) {
+				mutex_unlock(&JFS_IP(new_ip)->commit_mutex);
+				if (old_dir != new_dir)
+					mutex_unlock(&JFS_IP(old_dir)->commit_mutex);
+				mutex_unlock(&JFS_IP(old_ip)->commit_mutex);
+				mutex_unlock(&JFS_IP(new_dir)->commit_mutex);
+				if (!S_ISDIR(old_ip->i_mode) && new_ip)
+					IWRITE_UNLOCK(new_ip);
+				jfs_error(new_ip->i_sb,
+					  "new_ip->i_nlink != 0\n");
+				return -EIO;
+			}
+			tblk = tid_to_tblock(tid);
+			tblk->xflag |= COMMIT_DELETE;
+			tblk->u.ip = new_ip;
+		} else if (new_ip->i_nlink == 0) {
+			assert(!test_cflag(COMMIT_Nolink, new_ip));
+			/* free block resources */
+			if ((new_size = commitZeroLink(tid, new_ip)) < 0) {
+				txAbort(tid, 1);	/* Marks FS Dirty */
+				rc = new_size;
+				goto out_tx;
+			}
+			tblk = tid_to_tblock(tid);
+			tblk->xflag |= COMMIT_DELETE;
+			tblk->u.ip = new_ip;
+		} else {
+			new_ip->i_ctime = current_time(new_ip);
+			mark_inode_dirty(new_ip);
+		}
+	} else {
+		/*
+		 * Add new directory entry
+		 */
+		rc = dtSearch(new_dir, &new_dname, &ino, &btstack,
+			      JFS_CREATE);
+		if (rc) {
+			jfs_err("jfs_rename didn't expect dtSearch to fail w/rc = %d",
+				rc);
+			goto out_tx;
+		}
+
+		ino = old_ip->i_ino;
+		rc = dtInsert(tid, new_dir, &new_dname, &ino, &btstack);
+		if (rc) {
+			if (rc == -EIO)
+				jfs_err("jfs_rename: dtInsert returned -EIO");
+			goto out_tx;
+		}
+		if (S_ISDIR(old_ip->i_mode))
+			inc_nlink(new_dir);
+	}
+	/*
+	 * Remove old directory entry
+	 */
+
+	ino = old_ip->i_ino;
+	rc = dtDelete(tid, old_dir, &old_dname, &ino, JFS_REMOVE);
+	if (rc) {
+		jfs_err("jfs_rename did not expect dtDelete to return rc = %d",
+			rc);
+		txAbort(tid, 1);	/* Marks Filesystem dirty */
+		goto out_tx;
+	}
+	if (S_ISDIR(old_ip->i_mode)) {
+		drop_nlink(old_dir);
+		if (old_dir != new_dir) {
+			/*
+			 * Change inode number of parent for moved directory
+			 */
+
+			JFS_IP(old_ip)->i_dtroot.header.idotdot =
+				cpu_to_le32(new_dir->i_ino);
+
+			/* Linelock header of dtree */
+			tlck = txLock(tid, old_ip,
+				    (struct metapage *) &JFS_IP(old_ip)->bxflag,
+				      tlckDTREE | tlckBTROOT | tlckRELINK);
+			dtlck = (struct dt_lock *) & tlck->lock;
+			ASSERT(dtlck->index == 0);
+			lv = & dtlck->lv[0];
+			lv->offset = 0;
+			lv->length = 1;
+			dtlck->index++;
+		}
+	}
+
+	/*
+	 * Update ctime on changed/moved inodes & mark dirty
+	 */
+	old_ip->i_ctime = current_time(old_ip);
+	mark_inode_dirty(old_ip);
+
+	new_dir->i_ctime = new_dir->i_mtime = current_time(new_dir);
+	mark_inode_dirty(new_dir);
+
+	/* Build list of inodes modified by this transaction */
+	ipcount = 0;
+	iplist[ipcount++] = old_ip;
+	if (new_ip)
+		iplist[ipcount++] = new_ip;
+	iplist[ipcount++] = old_dir;
+
+	if (old_dir != new_dir) {
+		iplist[ipcount++] = new_dir;
+		old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
+		mark_inode_dirty(old_dir);
+	}
+
+	/*
+	 * Incomplete truncate of file data can
+	 * result in timing problems unless we synchronously commit the
+	 * transaction.
+	 */
+	if (new_size)
+		commit_flag = COMMIT_SYNC;
+	else
+		commit_flag = 0;
+
+	rc = txCommit(tid, ipcount, iplist, commit_flag);
+
+      out_tx:
+	txEnd(tid);
+	if (new_ip)
+		mutex_unlock(&JFS_IP(new_ip)->commit_mutex);
+	if (old_dir != new_dir)
+		mutex_unlock(&JFS_IP(old_dir)->commit_mutex);
+	mutex_unlock(&JFS_IP(old_ip)->commit_mutex);
+	mutex_unlock(&JFS_IP(new_dir)->commit_mutex);
+
+	while (new_size && (rc == 0)) {
+		tid = txBegin(new_ip->i_sb, 0);
+		mutex_lock(&JFS_IP(new_ip)->commit_mutex);
+		new_size = xtTruncate_pmap(tid, new_ip, new_size);
+		if (new_size < 0) {
+			txAbort(tid, 1);
+			rc = new_size;
+		} else
+			rc = txCommit(tid, 1, &new_ip, COMMIT_SYNC);
+		txEnd(tid);
+		mutex_unlock(&JFS_IP(new_ip)->commit_mutex);
+	}
+	if (new_ip && (new_ip->i_nlink == 0))
+		set_cflag(COMMIT_Nolink, new_ip);
+	/*
+	 * Truncating the directory index table is not guaranteed.  It
+	 * may need to be done iteratively
+	 */
+	if (test_cflag(COMMIT_Stale, old_dir)) {
+		if (old_dir->i_size > 1)
+			jfs_truncate_nolock(old_dir, 0);
+
+		clear_cflag(COMMIT_Stale, old_dir);
+	}
+      out_unlock:
+	if (new_ip && !S_ISDIR(new_ip->i_mode))
+		IWRITE_UNLOCK(new_ip);
+      out3:
+	free_UCSname(&new_dname);
+      out2:
+	free_UCSname(&old_dname);
+      out1:
+	jfs_info("jfs_rename: returning %d", rc);
+	return rc;
+}
+
+
+/*
+ * NAME:	jfs_mknod
+ *
+ * FUNCTION:	Create a special file (device)
+ */
+static int jfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode, dev_t rdev)
+{
+	struct jfs_inode_info *jfs_ip;
+	struct btstack btstack;
+	struct component_name dname;
+	ino_t ino;
+	struct inode *ip;
+	struct inode *iplist[2];
+	int rc;
+	tid_t tid;
+	struct tblock *tblk;
+
+	jfs_info("jfs_mknod: %pd", dentry);
+
+	rc = dquot_initialize(dir);
+	if (rc)
+		goto out;
+
+	if ((rc = get_UCSname(&dname, dentry)))
+		goto out;
+
+	ip = ialloc(dir, mode);
+	if (IS_ERR(ip)) {
+		rc = PTR_ERR(ip);
+		goto out1;
+	}
+	jfs_ip = JFS_IP(ip);
+
+	tid = txBegin(dir->i_sb, 0);
+
+	mutex_lock_nested(&JFS_IP(dir)->commit_mutex, COMMIT_MUTEX_PARENT);
+	mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
+
+	rc = jfs_init_acl(tid, ip, dir);
+	if (rc)
+		goto out3;
+
+	rc = jfs_init_security(tid, ip, dir, &dentry->d_name);
+	if (rc) {
+		txAbort(tid, 0);
+		goto out3;
+	}
+
+	if ((rc = dtSearch(dir, &dname, &ino, &btstack, JFS_CREATE))) {
+		txAbort(tid, 0);
+		goto out3;
+	}
+
+	tblk = tid_to_tblock(tid);
+	tblk->xflag |= COMMIT_CREATE;
+	tblk->ino = ip->i_ino;
+	tblk->u.ixpxd = JFS_IP(ip)->ixpxd;
+
+	ino = ip->i_ino;
+	if ((rc = dtInsert(tid, dir, &dname, &ino, &btstack))) {
+		txAbort(tid, 0);
+		goto out3;
+	}
+
+	ip->i_op = &jfs_file_inode_operations;
+	jfs_ip->dev = new_encode_dev(rdev);
+	init_special_inode(ip, ip->i_mode, rdev);
+
+	mark_inode_dirty(ip);
+
+	dir->i_ctime = dir->i_mtime = current_time(dir);
+
+	mark_inode_dirty(dir);
+
+	iplist[0] = dir;
+	iplist[1] = ip;
+	rc = txCommit(tid, 2, iplist, 0);
+
+      out3:
+	txEnd(tid);
+	mutex_unlock(&JFS_IP(ip)->commit_mutex);
+	mutex_unlock(&JFS_IP(dir)->commit_mutex);
+	if (rc) {
+		free_ea_wmap(ip);
+		clear_nlink(ip);
+		discard_new_inode(ip);
+	} else {
+		d_instantiate_new(dentry, ip);
+	}
+
+      out1:
+	free_UCSname(&dname);
+
+      out:
+	jfs_info("jfs_mknod: returning %d", rc);
+	return rc;
+}
+
+static struct dentry *jfs_lookup(struct inode *dip, struct dentry *dentry, unsigned int flags)
+{
+	struct btstack btstack;
+	ino_t inum;
+	struct inode *ip;
+	struct component_name key;
+	int rc;
+
+	jfs_info("jfs_lookup: name = %pd", dentry);
+
+	if ((rc = get_UCSname(&key, dentry)))
+		return ERR_PTR(rc);
+	rc = dtSearch(dip, &key, &inum, &btstack, JFS_LOOKUP);
+	free_UCSname(&key);
+	if (rc == -ENOENT) {
+		ip = NULL;
+	} else if (rc) {
+		jfs_err("jfs_lookup: dtSearch returned %d", rc);
+		ip = ERR_PTR(rc);
+	} else {
+		ip = jfs_iget(dip->i_sb, inum);
+		if (IS_ERR(ip))
+			jfs_err("jfs_lookup: iget failed on inum %d", (uint)inum);
+	}
+
+	return d_splice_alias(ip, dentry);
+}
+
+static struct inode *jfs_nfs_get_inode(struct super_block *sb,
+		u64 ino, u32 generation)
+{
+	struct inode *inode;
+
+	if (ino == 0)
+		return ERR_PTR(-ESTALE);
+	inode = jfs_iget(sb, ino);
+	if (IS_ERR(inode))
+		return ERR_CAST(inode);
+
+	if (generation && inode->i_generation != generation) {
+		iput(inode);
+		return ERR_PTR(-ESTALE);
+	}
+
+	return inode;
+}
+
+struct dentry *jfs_fh_to_dentry(struct super_block *sb, struct fid *fid,
+		int fh_len, int fh_type)
+{
+	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
+				    jfs_nfs_get_inode);
+}
+
+struct dentry *jfs_fh_to_parent(struct super_block *sb, struct fid *fid,
+		int fh_len, int fh_type)
+{
+	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
+				    jfs_nfs_get_inode);
+}
+
+struct dentry *jfs_get_parent(struct dentry *dentry)
+{
+	unsigned long parent_ino;
+
+	parent_ino =
+		le32_to_cpu(JFS_IP(d_inode(dentry))->i_dtroot.header.idotdot);
+
+	return d_obtain_alias(jfs_iget(dentry->d_sb, parent_ino));
+}
+
+const struct inode_operations jfs_dir_inode_operations = {
+	.create		= jfs_create,
+	.lookup		= jfs_lookup,
+	.link		= jfs_link,
+	.unlink		= jfs_unlink,
+	.symlink	= jfs_symlink,
+	.mkdir		= jfs_mkdir,
+	.rmdir		= jfs_rmdir,
+	.mknod		= jfs_mknod,
+	.rename		= jfs_rename,
+	.listxattr	= jfs_listxattr,
+	.setattr	= jfs_setattr,
+	.fileattr_get	= jfs_fileattr_get,
+	.fileattr_set	= jfs_fileattr_set,
+#ifdef CONFIG_JFS_POSIX_ACL
+	.get_acl	= jfs_get_acl,
+	.set_acl	= jfs_set_acl,
+#endif
+};
+
+const struct file_operations jfs_dir_operations = {
+	.read		= generic_read_dir,
+	.iterate	= jfs_readdir,
+	.fsync		= jfs_fsync,
+	.unlocked_ioctl = jfs_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+	.llseek		= generic_file_llseek,
+};
+
+static int jfs_ci_hash(const struct dentry *dir, struct qstr *this)
+{
+	unsigned long hash;
+	int i;
+
+	hash = init_name_hash(dir);
+	for (i=0; i < this->len; i++)
+		hash = partial_name_hash(tolower(this->name[i]), hash);
+	this->hash = end_name_hash(hash);
+
+	return 0;
+}
+
+static int jfs_ci_compare(const struct dentry *dentry,
+		unsigned int len, const char *str, const struct qstr *name)
+{
+	int i, result = 1;
+
+	if (len != name->len)
+		goto out;
+	for (i=0; i < len; i++) {
+		if (tolower(str[i]) != tolower(name->name[i]))
+			goto out;
+	}
+	result = 0;
+out:
+	return result;
+}
+
+static int jfs_ci_revalidate(struct dentry *dentry, unsigned int flags)
+{
+	/*
+	 * This is not negative dentry. Always valid.
+	 *
+	 * Note, rename() to existing directory entry will have ->d_inode,
+	 * and will use existing name which isn't specified name by user.
+	 *
+	 * We may be able to drop this positive dentry here. But dropping
+	 * positive dentry isn't good idea. So it's unsupported like
+	 * rename("filename", "FILENAME") for now.
+	 */
+	if (d_really_is_positive(dentry))
+		return 1;
+
+	/*
+	 * This may be nfsd (or something), anyway, we can't see the
+	 * intent of this. So, since this can be for creation, drop it.
+	 */
+	if (!flags)
+		return 0;
+
+	/*
+	 * Drop the negative dentry, in order to make sure to use the
+	 * case sensitive name which is specified by user if this is
+	 * for creation.
+	 */
+	if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
+		return 0;
+	return 1;
+}
+
+const struct dentry_operations jfs_ci_dentry_operations =
+{
+	.d_hash = jfs_ci_hash,
+	.d_compare = jfs_ci_compare,
+	.d_revalidate = jfs_ci_revalidate,
+};
diff --git a/fs/jfs/resize.c b/fs/jfs/resize.c
new file mode 100644
index 000000000..8b9a72ae5
--- /dev/null
+++ b/fs/jfs/resize.c
@@ -0,0 +1,536 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines  Corp., 2000-2004
+*/
+
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include <linux/quotaops.h>
+#include <linux/blkdev.h>
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_metapage.h"
+#include "jfs_dinode.h"
+#include "jfs_imap.h"
+#include "jfs_dmap.h"
+#include "jfs_superblock.h"
+#include "jfs_txnmgr.h"
+#include "jfs_debug.h"
+
+#define BITSPERPAGE	(PSIZE << 3)
+#define L2MEGABYTE	20
+#define MEGABYTE	(1 << L2MEGABYTE)
+#define MEGABYTE32	(MEGABYTE << 5)
+
+/* convert block number to bmap file page number */
+#define BLKTODMAPN(b)\
+	(((b) >> 13) + ((b) >> 23) + ((b) >> 33) + 3 + 1)
+
+/*
+ *	jfs_extendfs()
+ *
+ * function: extend file system;
+ *
+ *   |-------------------------------|----------|----------|
+ *   file system space               fsck       inline log
+ *                                   workspace  space
+ *
+ * input:
+ *	new LVSize: in LV blocks (required)
+ *	new LogSize: in LV blocks (optional)
+ *	new FSSize: in LV blocks (optional)
+ *
+ * new configuration:
+ * 1. set new LogSize as specified or default from new LVSize;
+ * 2. compute new FSCKSize from new LVSize;
+ * 3. set new FSSize as MIN(FSSize, LVSize-(LogSize+FSCKSize)) where
+ *    assert(new FSSize >= old FSSize),
+ *    i.e., file system must not be shrunk;
+ */
+int jfs_extendfs(struct super_block *sb, s64 newLVSize, int newLogSize)
+{
+	int rc = 0;
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct inode *ipbmap = sbi->ipbmap;
+	struct inode *ipbmap2;
+	struct inode *ipimap = sbi->ipimap;
+	struct jfs_log *log = sbi->log;
+	struct bmap *bmp = sbi->bmap;
+	s64 newLogAddress, newFSCKAddress;
+	int newFSCKSize;
+	s64 newMapSize = 0, mapSize;
+	s64 XAddress, XSize, nblocks, xoff, xaddr, t64;
+	s64 oldLVSize;
+	s64 newFSSize;
+	s64 VolumeSize;
+	int newNpages = 0, nPages, newPage, xlen, t32;
+	int tid;
+	int log_formatted = 0;
+	struct inode *iplist[1];
+	struct jfs_superblock *j_sb, *j_sb2;
+	s64 old_agsize;
+	int agsizechanged = 0;
+	struct buffer_head *bh, *bh2;
+
+	/* If the volume hasn't grown, get out now */
+
+	if (sbi->mntflag & JFS_INLINELOG)
+		oldLVSize = addressPXD(&sbi->logpxd) + lengthPXD(&sbi->logpxd);
+	else
+		oldLVSize = addressPXD(&sbi->fsckpxd) +
+		    lengthPXD(&sbi->fsckpxd);
+
+	if (oldLVSize >= newLVSize) {
+		printk(KERN_WARNING
+		       "jfs_extendfs: volume hasn't grown, returning\n");
+		goto out;
+	}
+
+	VolumeSize = sb_bdev_nr_blocks(sb);
+	if (VolumeSize) {
+		if (newLVSize > VolumeSize) {
+			printk(KERN_WARNING "jfs_extendfs: invalid size\n");
+			rc = -EINVAL;
+			goto out;
+		}
+	} else {
+		/* check the device */
+		bh = sb_bread(sb, newLVSize - 1);
+		if (!bh) {
+			printk(KERN_WARNING "jfs_extendfs: invalid size\n");
+			rc = -EINVAL;
+			goto out;
+		}
+		bforget(bh);
+	}
+
+	/* Can't extend write-protected drive */
+
+	if (isReadOnly(ipbmap)) {
+		printk(KERN_WARNING "jfs_extendfs: read-only file system\n");
+		rc = -EROFS;
+		goto out;
+	}
+
+	/*
+	 *	reconfigure LV spaces
+	 *	---------------------
+	 *
+	 * validate new size, or, if not specified, determine new size
+	 */
+
+	/*
+	 * reconfigure inline log space:
+	 */
+	if ((sbi->mntflag & JFS_INLINELOG)) {
+		if (newLogSize == 0) {
+			/*
+			 * no size specified: default to 1/256 of aggregate
+			 * size; rounded up to a megabyte boundary;
+			 */
+			newLogSize = newLVSize >> 8;
+			t32 = (1 << (20 - sbi->l2bsize)) - 1;
+			newLogSize = (newLogSize + t32) & ~t32;
+			newLogSize =
+			    min(newLogSize, MEGABYTE32 >> sbi->l2bsize);
+		} else {
+			/*
+			 * convert the newLogSize to fs blocks.
+			 *
+			 * Since this is given in megabytes, it will always be
+			 * an even number of pages.
+			 */
+			newLogSize = (newLogSize * MEGABYTE) >> sbi->l2bsize;
+		}
+
+	} else
+		newLogSize = 0;
+
+	newLogAddress = newLVSize - newLogSize;
+
+	/*
+	 * reconfigure fsck work space:
+	 *
+	 * configure it to the end of the logical volume regardless of
+	 * whether file system extends to the end of the aggregate;
+	 * Need enough 4k pages to cover:
+	 *  - 1 bit per block in aggregate rounded up to BPERDMAP boundary
+	 *  - 1 extra page to handle control page and intermediate level pages
+	 *  - 50 extra pages for the chkdsk service log
+	 */
+	t64 = ((newLVSize - newLogSize + BPERDMAP - 1) >> L2BPERDMAP)
+	    << L2BPERDMAP;
+	t32 = DIV_ROUND_UP(t64, BITSPERPAGE) + 1 + 50;
+	newFSCKSize = t32 << sbi->l2nbperpage;
+	newFSCKAddress = newLogAddress - newFSCKSize;
+
+	/*
+	 * compute new file system space;
+	 */
+	newFSSize = newLVSize - newLogSize - newFSCKSize;
+
+	/* file system cannot be shrunk */
+	if (newFSSize < bmp->db_mapsize) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * If we're expanding enough that the inline log does not overlap
+	 * the old one, we can format the new log before we quiesce the
+	 * filesystem.
+	 */
+	if ((sbi->mntflag & JFS_INLINELOG) && (newLogAddress > oldLVSize)) {
+		if ((rc = lmLogFormat(log, newLogAddress, newLogSize)))
+			goto out;
+		log_formatted = 1;
+	}
+	/*
+	 *	quiesce file system
+	 *
+	 * (prepare to move the inline log and to prevent map update)
+	 *
+	 * block any new transactions and wait for completion of
+	 * all wip transactions and flush modified pages s.t.
+	 * on-disk file system is in consistent state and
+	 * log is not required for recovery.
+	 */
+	txQuiesce(sb);
+
+	/* Reset size of direct inode */
+	sbi->direct_inode->i_size = bdev_nr_bytes(sb->s_bdev);
+
+	if (sbi->mntflag & JFS_INLINELOG) {
+		/*
+		 * deactivate old inline log
+		 */
+		lmLogShutdown(log);
+
+		/*
+		 * mark on-disk super block for fs in transition;
+		 *
+		 * update on-disk superblock for the new space configuration
+		 * of inline log space and fsck work space descriptors:
+		 * N.B. FS descriptor is NOT updated;
+		 *
+		 * crash recovery:
+		 * logredo(): if FM_EXTENDFS, return to fsck() for cleanup;
+		 * fsck(): if FM_EXTENDFS, reformat inline log and fsck
+		 * workspace from superblock inline log descriptor and fsck
+		 * workspace descriptor;
+		 */
+
+		/* read in superblock */
+		if ((rc = readSuper(sb, &bh)))
+			goto error_out;
+		j_sb = (struct jfs_superblock *)bh->b_data;
+
+		/* mark extendfs() in progress */
+		j_sb->s_state |= cpu_to_le32(FM_EXTENDFS);
+		j_sb->s_xsize = cpu_to_le64(newFSSize);
+		PXDaddress(&j_sb->s_xfsckpxd, newFSCKAddress);
+		PXDlength(&j_sb->s_xfsckpxd, newFSCKSize);
+		PXDaddress(&j_sb->s_xlogpxd, newLogAddress);
+		PXDlength(&j_sb->s_xlogpxd, newLogSize);
+
+		/* synchronously update superblock */
+		mark_buffer_dirty(bh);
+		sync_dirty_buffer(bh);
+		brelse(bh);
+
+		/*
+		 * format new inline log synchronously;
+		 *
+		 * crash recovery: if log move in progress,
+		 * reformat log and exit success;
+		 */
+		if (!log_formatted)
+			if ((rc = lmLogFormat(log, newLogAddress, newLogSize)))
+				goto error_out;
+
+		/*
+		 * activate new log
+		 */
+		log->base = newLogAddress;
+		log->size = newLogSize >> (L2LOGPSIZE - sb->s_blocksize_bits);
+		if ((rc = lmLogInit(log)))
+			goto error_out;
+	}
+
+	/*
+	 *	extend block allocation map
+	 *	---------------------------
+	 *
+	 * extendfs() for new extension, retry after crash recovery;
+	 *
+	 * note: both logredo() and fsck() rebuild map from
+	 * the bitmap and configuration parameter from superblock
+	 * (disregarding all other control information in the map);
+	 *
+	 * superblock:
+	 *  s_size: aggregate size in physical blocks;
+	 */
+	/*
+	 *	compute the new block allocation map configuration
+	 *
+	 * map dinode:
+	 *  di_size: map file size in byte;
+	 *  di_nblocks: number of blocks allocated for map file;
+	 *  di_mapsize: number of blocks in aggregate (covered by map);
+	 * map control page:
+	 *  db_mapsize: number of blocks in aggregate (covered by map);
+	 */
+	newMapSize = newFSSize;
+	/* number of data pages of new bmap file:
+	 * roundup new size to full dmap page boundary and
+	 * add 1 extra dmap page for next extendfs()
+	 */
+	t64 = (newMapSize - 1) + BPERDMAP;
+	newNpages = BLKTODMAPN(t64) + 1;
+
+	/*
+	 *	extend map from current map (WITHOUT growing mapfile)
+	 *
+	 * map new extension with unmapped part of the last partial
+	 * dmap page, if applicable, and extra page(s) allocated
+	 * at end of bmap by mkfs() or previous extendfs();
+	 */
+      extendBmap:
+	/* compute number of blocks requested to extend */
+	mapSize = bmp->db_mapsize;
+	XAddress = mapSize;	/* eXtension Address */
+	XSize = newMapSize - mapSize;	/* eXtension Size */
+	old_agsize = bmp->db_agsize;	/* We need to know if this changes */
+
+	/* compute number of blocks that can be extended by current mapfile */
+	t64 = dbMapFileSizeToMapSize(ipbmap);
+	if (mapSize > t64) {
+		printk(KERN_ERR "jfs_extendfs: mapSize (0x%Lx) > t64 (0x%Lx)\n",
+		       (long long) mapSize, (long long) t64);
+		rc = -EIO;
+		goto error_out;
+	}
+	nblocks = min(t64 - mapSize, XSize);
+
+	/*
+	 * update map pages for new extension:
+	 *
+	 * update/init dmap and bubble up the control hierarchy
+	 * incrementally fold up dmaps into upper levels;
+	 * update bmap control page;
+	 */
+	if ((rc = dbExtendFS(ipbmap, XAddress, nblocks)))
+		goto error_out;
+
+	agsizechanged |= (bmp->db_agsize != old_agsize);
+
+	/*
+	 * the map now has extended to cover additional nblocks:
+	 * dn_mapsize = oldMapsize + nblocks;
+	 */
+	/* ipbmap->i_mapsize += nblocks; */
+	XSize -= nblocks;
+
+	/*
+	 *	grow map file to cover remaining extension
+	 *	and/or one extra dmap page for next extendfs();
+	 *
+	 * allocate new map pages and its backing blocks, and
+	 * update map file xtree
+	 */
+	/* compute number of data pages of current bmap file */
+	nPages = ipbmap->i_size >> L2PSIZE;
+
+	/* need to grow map file ? */
+	if (nPages == newNpages)
+		goto finalizeBmap;
+
+	/*
+	 * grow bmap file for the new map pages required:
+	 *
+	 * allocate growth at the start of newly extended region;
+	 * bmap file only grows sequentially, i.e., both data pages
+	 * and possibly xtree index pages may grow in append mode,
+	 * s.t. logredo() can reconstruct pre-extension state
+	 * by washing away bmap file of pages outside s_size boundary;
+	 */
+	/*
+	 * journal map file growth as if a regular file growth:
+	 * (note: bmap is created with di_mode = IFJOURNAL|IFREG);
+	 *
+	 * journaling of bmap file growth is not required since
+	 * logredo() do/can not use log records of bmap file growth
+	 * but it provides careful write semantics, pmap update, etc.;
+	 */
+	/* synchronous write of data pages: bmap data pages are
+	 * cached in meta-data cache, and not written out
+	 * by txCommit();
+	 */
+	rc = filemap_fdatawait(ipbmap->i_mapping);
+	if (rc)
+		goto error_out;
+
+	rc = filemap_write_and_wait(ipbmap->i_mapping);
+	if (rc)
+		goto error_out;
+
+	diWriteSpecial(ipbmap, 0);
+
+	newPage = nPages;	/* first new page number */
+	xoff = newPage << sbi->l2nbperpage;
+	xlen = (newNpages - nPages) << sbi->l2nbperpage;
+	xlen = min(xlen, (int) nblocks) & ~(sbi->nbperpage - 1);
+	xaddr = XAddress;
+
+	tid = txBegin(sb, COMMIT_FORCE);
+
+	if ((rc = xtAppend(tid, ipbmap, 0, xoff, nblocks, &xlen, &xaddr, 0))) {
+		txEnd(tid);
+		goto error_out;
+	}
+	/* update bmap file size */
+	ipbmap->i_size += xlen << sbi->l2bsize;
+	inode_add_bytes(ipbmap, xlen << sbi->l2bsize);
+
+	iplist[0] = ipbmap;
+	rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
+
+	txEnd(tid);
+
+	if (rc)
+		goto error_out;
+
+	/*
+	 * map file has been grown now to cover extension to further out;
+	 * di_size = new map file size;
+	 *
+	 * if huge extension, the previous extension based on previous
+	 * map file size may not have been sufficient to cover whole extension
+	 * (it could have been used up for new map pages),
+	 * but the newly grown map file now covers lot bigger new free space
+	 * available for further extension of map;
+	 */
+	/* any more blocks to extend ? */
+	if (XSize)
+		goto extendBmap;
+
+      finalizeBmap:
+	/* finalize bmap */
+	dbFinalizeBmap(ipbmap);
+
+	/*
+	 *	update inode allocation map
+	 *	---------------------------
+	 *
+	 * move iag lists from old to new iag;
+	 * agstart field is not updated for logredo() to reconstruct
+	 * iag lists if system crash occurs.
+	 * (computation of ag number from agstart based on agsize
+	 * will correctly identify the new ag);
+	 */
+	/* if new AG size the same as old AG size, done! */
+	if (agsizechanged) {
+		if ((rc = diExtendFS(ipimap, ipbmap)))
+			goto error_out;
+
+		/* finalize imap */
+		if ((rc = diSync(ipimap)))
+			goto error_out;
+	}
+
+	/*
+	 *	finalize
+	 *	--------
+	 *
+	 * extension is committed when on-disk super block is
+	 * updated with new descriptors: logredo will recover
+	 * crash before it to pre-extension state;
+	 */
+
+	/* sync log to skip log replay of bmap file growth transaction; */
+	/* lmLogSync(log, 1); */
+
+	/*
+	 * synchronous write bmap global control page;
+	 * for crash before completion of write
+	 * logredo() will recover to pre-extendfs state;
+	 * for crash after completion of write,
+	 * logredo() will recover post-extendfs state;
+	 */
+	if ((rc = dbSync(ipbmap)))
+		goto error_out;
+
+	/*
+	 * copy primary bmap inode to secondary bmap inode
+	 */
+
+	ipbmap2 = diReadSpecial(sb, BMAP_I, 1);
+	if (ipbmap2 == NULL) {
+		printk(KERN_ERR "jfs_extendfs: diReadSpecial(bmap) failed\n");
+		goto error_out;
+	}
+	memcpy(&JFS_IP(ipbmap2)->i_xtroot, &JFS_IP(ipbmap)->i_xtroot, 288);
+	ipbmap2->i_size = ipbmap->i_size;
+	ipbmap2->i_blocks = ipbmap->i_blocks;
+
+	diWriteSpecial(ipbmap2, 1);
+	diFreeSpecial(ipbmap2);
+
+	/*
+	 *	update superblock
+	 */
+	if ((rc = readSuper(sb, &bh)))
+		goto error_out;
+	j_sb = (struct jfs_superblock *)bh->b_data;
+
+	/* mark extendfs() completion */
+	j_sb->s_state &= cpu_to_le32(~FM_EXTENDFS);
+	j_sb->s_size = cpu_to_le64(bmp->db_mapsize <<
+				   le16_to_cpu(j_sb->s_l2bfactor));
+	j_sb->s_agsize = cpu_to_le32(bmp->db_agsize);
+
+	/* update inline log space descriptor */
+	if (sbi->mntflag & JFS_INLINELOG) {
+		PXDaddress(&(j_sb->s_logpxd), newLogAddress);
+		PXDlength(&(j_sb->s_logpxd), newLogSize);
+	}
+
+	/* record log's mount serial number */
+	j_sb->s_logserial = cpu_to_le32(log->serial);
+
+	/* update fsck work space descriptor */
+	PXDaddress(&(j_sb->s_fsckpxd), newFSCKAddress);
+	PXDlength(&(j_sb->s_fsckpxd), newFSCKSize);
+	j_sb->s_fscklog = 1;
+	/* sb->s_fsckloglen remains the same */
+
+	/* Update secondary superblock */
+	bh2 = sb_bread(sb, SUPER2_OFF >> sb->s_blocksize_bits);
+	if (bh2) {
+		j_sb2 = (struct jfs_superblock *)bh2->b_data;
+		memcpy(j_sb2, j_sb, sizeof (struct jfs_superblock));
+
+		mark_buffer_dirty(bh);
+		sync_dirty_buffer(bh2);
+		brelse(bh2);
+	}
+
+	/* write primary superblock */
+	mark_buffer_dirty(bh);
+	sync_dirty_buffer(bh);
+	brelse(bh);
+
+	goto resume;
+
+      error_out:
+	jfs_error(sb, "\n");
+
+      resume:
+	/*
+	 *	resume file system transactions
+	 */
+	txResume(sb);
+
+      out:
+	return rc;
+}
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
new file mode 100644
index 000000000..85d4f44f2
--- /dev/null
+++ b/fs/jfs/super.c
@@ -0,0 +1,1046 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *   Portions Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/parser.h>
+#include <linux/completion.h>
+#include <linux/vfs.h>
+#include <linux/quotaops.h>
+#include <linux/mount.h>
+#include <linux/moduleparam.h>
+#include <linux/kthread.h>
+#include <linux/posix_acl.h>
+#include <linux/buffer_head.h>
+#include <linux/exportfs.h>
+#include <linux/crc32.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/seq_file.h>
+#include <linux/blkdev.h>
+
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_inode.h"
+#include "jfs_metapage.h"
+#include "jfs_superblock.h"
+#include "jfs_dmap.h"
+#include "jfs_imap.h"
+#include "jfs_acl.h"
+#include "jfs_debug.h"
+#include "jfs_xattr.h"
+#include "jfs_dinode.h"
+
+MODULE_DESCRIPTION("The Journaled Filesystem (JFS)");
+MODULE_AUTHOR("Steve Best/Dave Kleikamp/Barry Arndt, IBM");
+MODULE_LICENSE("GPL");
+
+static struct kmem_cache *jfs_inode_cachep;
+
+static const struct super_operations jfs_super_operations;
+static const struct export_operations jfs_export_operations;
+static struct file_system_type jfs_fs_type;
+
+#define MAX_COMMIT_THREADS 64
+static int commit_threads;
+module_param(commit_threads, int, 0);
+MODULE_PARM_DESC(commit_threads, "Number of commit threads");
+
+static struct task_struct *jfsCommitThread[MAX_COMMIT_THREADS];
+struct task_struct *jfsIOthread;
+struct task_struct *jfsSyncThread;
+
+#ifdef CONFIG_JFS_DEBUG
+int jfsloglevel = JFS_LOGLEVEL_WARN;
+module_param(jfsloglevel, int, 0644);
+MODULE_PARM_DESC(jfsloglevel, "Specify JFS loglevel (0, 1 or 2)");
+#endif
+
+static void jfs_handle_error(struct super_block *sb)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+
+	if (sb_rdonly(sb))
+		return;
+
+	updateSuper(sb, FM_DIRTY);
+
+	if (sbi->flag & JFS_ERR_PANIC)
+		panic("JFS (device %s): panic forced after error\n",
+			sb->s_id);
+	else if (sbi->flag & JFS_ERR_REMOUNT_RO) {
+		jfs_err("ERROR: (device %s): remounting filesystem as read-only",
+			sb->s_id);
+		sb->s_flags |= SB_RDONLY;
+	}
+
+	/* nothing is done for continue beyond marking the superblock dirty */
+}
+
+void jfs_error(struct super_block *sb, const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	pr_err("ERROR: (device %s): %ps: %pV\n",
+	       sb->s_id, __builtin_return_address(0), &vaf);
+
+	va_end(args);
+
+	jfs_handle_error(sb);
+}
+
+static struct inode *jfs_alloc_inode(struct super_block *sb)
+{
+	struct jfs_inode_info *jfs_inode;
+
+	jfs_inode = alloc_inode_sb(sb, jfs_inode_cachep, GFP_NOFS);
+	if (!jfs_inode)
+		return NULL;
+#ifdef CONFIG_QUOTA
+	memset(&jfs_inode->i_dquot, 0, sizeof(jfs_inode->i_dquot));
+#endif
+	return &jfs_inode->vfs_inode;
+}
+
+static void jfs_free_inode(struct inode *inode)
+{
+	kmem_cache_free(jfs_inode_cachep, JFS_IP(inode));
+}
+
+static int jfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(dentry->d_sb);
+	s64 maxinodes;
+	struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;
+
+	jfs_info("In jfs_statfs");
+	buf->f_type = JFS_SUPER_MAGIC;
+	buf->f_bsize = sbi->bsize;
+	buf->f_blocks = sbi->bmap->db_mapsize;
+	buf->f_bfree = sbi->bmap->db_nfree;
+	buf->f_bavail = sbi->bmap->db_nfree;
+	/*
+	 * If we really return the number of allocated & free inodes, some
+	 * applications will fail because they won't see enough free inodes.
+	 * We'll try to calculate some guess as to how many inodes we can
+	 * really allocate
+	 *
+	 * buf->f_files = atomic_read(&imap->im_numinos);
+	 * buf->f_ffree = atomic_read(&imap->im_numfree);
+	 */
+	maxinodes = min((s64) atomic_read(&imap->im_numinos) +
+			((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
+			 << L2INOSPEREXT), (s64) 0xffffffffLL);
+	buf->f_files = maxinodes;
+	buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
+				    atomic_read(&imap->im_numfree));
+	buf->f_fsid.val[0] = crc32_le(0, (char *)&sbi->uuid,
+				      sizeof(sbi->uuid)/2);
+	buf->f_fsid.val[1] = crc32_le(0,
+				      (char *)&sbi->uuid + sizeof(sbi->uuid)/2,
+				      sizeof(sbi->uuid)/2);
+
+	buf->f_namelen = JFS_NAME_MAX;
+	return 0;
+}
+
+#ifdef CONFIG_QUOTA
+static int jfs_quota_off(struct super_block *sb, int type);
+static int jfs_quota_on(struct super_block *sb, int type, int format_id,
+			const struct path *path);
+
+static void jfs_quota_off_umount(struct super_block *sb)
+{
+	int type;
+
+	for (type = 0; type < MAXQUOTAS; type++)
+		jfs_quota_off(sb, type);
+}
+
+static const struct quotactl_ops jfs_quotactl_ops = {
+	.quota_on	= jfs_quota_on,
+	.quota_off	= jfs_quota_off,
+	.quota_sync	= dquot_quota_sync,
+	.get_state	= dquot_get_state,
+	.set_info	= dquot_set_dqinfo,
+	.get_dqblk	= dquot_get_dqblk,
+	.set_dqblk	= dquot_set_dqblk,
+	.get_nextdqblk	= dquot_get_next_dqblk,
+};
+#else
+static inline void jfs_quota_off_umount(struct super_block *sb)
+{
+}
+#endif
+
+static void jfs_put_super(struct super_block *sb)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	int rc;
+
+	jfs_info("In jfs_put_super");
+
+	jfs_quota_off_umount(sb);
+
+	rc = jfs_umount(sb);
+	if (rc)
+		jfs_err("jfs_umount failed with return code %d", rc);
+
+	unload_nls(sbi->nls_tab);
+
+	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
+	iput(sbi->direct_inode);
+
+	kfree(sbi);
+}
+
+enum {
+	Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
+	Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, Opt_quota,
+	Opt_usrquota, Opt_grpquota, Opt_uid, Opt_gid, Opt_umask,
+	Opt_discard, Opt_nodiscard, Opt_discard_minblk
+};
+
+static const match_table_t tokens = {
+	{Opt_integrity, "integrity"},
+	{Opt_nointegrity, "nointegrity"},
+	{Opt_iocharset, "iocharset=%s"},
+	{Opt_resize, "resize=%u"},
+	{Opt_resize_nosize, "resize"},
+	{Opt_errors, "errors=%s"},
+	{Opt_ignore, "noquota"},
+	{Opt_quota, "quota"},
+	{Opt_usrquota, "usrquota"},
+	{Opt_grpquota, "grpquota"},
+	{Opt_uid, "uid=%u"},
+	{Opt_gid, "gid=%u"},
+	{Opt_umask, "umask=%u"},
+	{Opt_discard, "discard"},
+	{Opt_nodiscard, "nodiscard"},
+	{Opt_discard_minblk, "discard=%u"},
+	{Opt_err, NULL}
+};
+
+static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
+			 int *flag)
+{
+	void *nls_map = (void *)-1;	/* -1: no change;  NULL: none */
+	char *p;
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+
+	*newLVSize = 0;
+
+	if (!options)
+		return 1;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		substring_t args[MAX_OPT_ARGS];
+		int token;
+		if (!*p)
+			continue;
+
+		token = match_token(p, tokens, args);
+		switch (token) {
+		case Opt_integrity:
+			*flag &= ~JFS_NOINTEGRITY;
+			break;
+		case Opt_nointegrity:
+			*flag |= JFS_NOINTEGRITY;
+			break;
+		case Opt_ignore:
+			/* Silently ignore the quota options */
+			/* Don't do anything ;-) */
+			break;
+		case Opt_iocharset:
+			if (nls_map && nls_map != (void *) -1)
+				unload_nls(nls_map);
+			if (!strcmp(args[0].from, "none"))
+				nls_map = NULL;
+			else {
+				nls_map = load_nls(args[0].from);
+				if (!nls_map) {
+					pr_err("JFS: charset not found\n");
+					goto cleanup;
+				}
+			}
+			break;
+		case Opt_resize:
+		{
+			char *resize = args[0].from;
+			int rc = kstrtoll(resize, 0, newLVSize);
+
+			if (rc)
+				goto cleanup;
+			break;
+		}
+		case Opt_resize_nosize:
+		{
+			*newLVSize = sb_bdev_nr_blocks(sb);
+			if (*newLVSize == 0)
+				pr_err("JFS: Cannot determine volume size\n");
+			break;
+		}
+		case Opt_errors:
+		{
+			char *errors = args[0].from;
+			if (!errors || !*errors)
+				goto cleanup;
+			if (!strcmp(errors, "continue")) {
+				*flag &= ~JFS_ERR_REMOUNT_RO;
+				*flag &= ~JFS_ERR_PANIC;
+				*flag |= JFS_ERR_CONTINUE;
+			} else if (!strcmp(errors, "remount-ro")) {
+				*flag &= ~JFS_ERR_CONTINUE;
+				*flag &= ~JFS_ERR_PANIC;
+				*flag |= JFS_ERR_REMOUNT_RO;
+			} else if (!strcmp(errors, "panic")) {
+				*flag &= ~JFS_ERR_CONTINUE;
+				*flag &= ~JFS_ERR_REMOUNT_RO;
+				*flag |= JFS_ERR_PANIC;
+			} else {
+				pr_err("JFS: %s is an invalid error handler\n",
+				       errors);
+				goto cleanup;
+			}
+			break;
+		}
+
+#ifdef CONFIG_QUOTA
+		case Opt_quota:
+		case Opt_usrquota:
+			*flag |= JFS_USRQUOTA;
+			break;
+		case Opt_grpquota:
+			*flag |= JFS_GRPQUOTA;
+			break;
+#else
+		case Opt_usrquota:
+		case Opt_grpquota:
+		case Opt_quota:
+			pr_err("JFS: quota operations not supported\n");
+			break;
+#endif
+		case Opt_uid:
+		{
+			char *uid = args[0].from;
+			uid_t val;
+			int rc = kstrtouint(uid, 0, &val);
+
+			if (rc)
+				goto cleanup;
+			sbi->uid = make_kuid(current_user_ns(), val);
+			if (!uid_valid(sbi->uid))
+				goto cleanup;
+			break;
+		}
+
+		case Opt_gid:
+		{
+			char *gid = args[0].from;
+			gid_t val;
+			int rc = kstrtouint(gid, 0, &val);
+
+			if (rc)
+				goto cleanup;
+			sbi->gid = make_kgid(current_user_ns(), val);
+			if (!gid_valid(sbi->gid))
+				goto cleanup;
+			break;
+		}
+
+		case Opt_umask:
+		{
+			char *umask = args[0].from;
+			int rc = kstrtouint(umask, 8, &sbi->umask);
+
+			if (rc)
+				goto cleanup;
+			if (sbi->umask & ~0777) {
+				pr_err("JFS: Invalid value of umask\n");
+				goto cleanup;
+			}
+			break;
+		}
+
+		case Opt_discard:
+			/* if set to 1, even copying files will cause
+			 * trimming :O
+			 * -> user has more control over the online trimming
+			 */
+			sbi->minblks_trim = 64;
+			if (bdev_max_discard_sectors(sb->s_bdev))
+				*flag |= JFS_DISCARD;
+			else
+				pr_err("JFS: discard option not supported on device\n");
+			break;
+
+		case Opt_nodiscard:
+			*flag &= ~JFS_DISCARD;
+			break;
+
+		case Opt_discard_minblk:
+		{
+			char *minblks_trim = args[0].from;
+			int rc;
+			if (bdev_max_discard_sectors(sb->s_bdev)) {
+				*flag |= JFS_DISCARD;
+				rc = kstrtouint(minblks_trim, 0,
+						&sbi->minblks_trim);
+				if (rc)
+					goto cleanup;
+			} else
+				pr_err("JFS: discard option not supported on device\n");
+			break;
+		}
+
+		default:
+			printk("jfs: Unrecognized mount option \"%s\" or missing value\n",
+			       p);
+			goto cleanup;
+		}
+	}
+
+	if (nls_map != (void *) -1) {
+		/* Discard old (if remount) */
+		unload_nls(sbi->nls_tab);
+		sbi->nls_tab = nls_map;
+	}
+	return 1;
+
+cleanup:
+	if (nls_map && nls_map != (void *) -1)
+		unload_nls(nls_map);
+	return 0;
+}
+
+static int jfs_remount(struct super_block *sb, int *flags, char *data)
+{
+	s64 newLVSize = 0;
+	int rc = 0;
+	int flag = JFS_SBI(sb)->flag;
+	int ret;
+
+	sync_filesystem(sb);
+	if (!parse_options(data, sb, &newLVSize, &flag))
+		return -EINVAL;
+
+	if (newLVSize) {
+		if (sb_rdonly(sb)) {
+			pr_err("JFS: resize requires volume to be mounted read-write\n");
+			return -EROFS;
+		}
+		rc = jfs_extendfs(sb, newLVSize, 0);
+		if (rc)
+			return rc;
+	}
+
+	if (sb_rdonly(sb) && !(*flags & SB_RDONLY)) {
+		/*
+		 * Invalidate any previously read metadata.  fsck may have
+		 * changed the on-disk data since we mounted r/o
+		 */
+		truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);
+
+		JFS_SBI(sb)->flag = flag;
+		ret = jfs_mount_rw(sb, 1);
+
+		/* mark the fs r/w for quota activity */
+		sb->s_flags &= ~SB_RDONLY;
+
+		dquot_resume(sb, -1);
+		return ret;
+	}
+	if (!sb_rdonly(sb) && (*flags & SB_RDONLY)) {
+		rc = dquot_suspend(sb, -1);
+		if (rc < 0)
+			return rc;
+		rc = jfs_umount_rw(sb);
+		JFS_SBI(sb)->flag = flag;
+		return rc;
+	}
+	if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
+		if (!sb_rdonly(sb)) {
+			rc = jfs_umount_rw(sb);
+			if (rc)
+				return rc;
+
+			JFS_SBI(sb)->flag = flag;
+			ret = jfs_mount_rw(sb, 1);
+			return ret;
+		}
+	JFS_SBI(sb)->flag = flag;
+
+	return 0;
+}
+
+static int jfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+	struct jfs_sb_info *sbi;
+	struct inode *inode;
+	int rc;
+	s64 newLVSize = 0;
+	int flag, ret = -EINVAL;
+
+	jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);
+
+	sbi = kzalloc(sizeof(struct jfs_sb_info), GFP_KERNEL);
+	if (!sbi)
+		return -ENOMEM;
+
+	sb->s_fs_info = sbi;
+	sb->s_max_links = JFS_LINK_MAX;
+	sb->s_time_min = 0;
+	sb->s_time_max = U32_MAX;
+	sbi->sb = sb;
+	sbi->uid = INVALID_UID;
+	sbi->gid = INVALID_GID;
+	sbi->umask = -1;
+
+	/* initialize the mount flag and determine the default error handler */
+	flag = JFS_ERR_REMOUNT_RO;
+
+	if (!parse_options((char *) data, sb, &newLVSize, &flag))
+		goto out_kfree;
+	sbi->flag = flag;
+
+#ifdef CONFIG_JFS_POSIX_ACL
+	sb->s_flags |= SB_POSIXACL;
+#endif
+
+	if (newLVSize) {
+		pr_err("resize option for remount only\n");
+		goto out_kfree;
+	}
+
+	/*
+	 * Initialize blocksize to 4K.
+	 */
+	sb_set_blocksize(sb, PSIZE);
+
+	/*
+	 * Set method vectors.
+	 */
+	sb->s_op = &jfs_super_operations;
+	sb->s_export_op = &jfs_export_operations;
+	sb->s_xattr = jfs_xattr_handlers;
+#ifdef CONFIG_QUOTA
+	sb->dq_op = &dquot_operations;
+	sb->s_qcop = &jfs_quotactl_ops;
+	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
+#endif
+
+	/*
+	 * Initialize direct-mapping inode/address-space
+	 */
+	inode = new_inode(sb);
+	if (inode == NULL) {
+		ret = -ENOMEM;
+		goto out_unload;
+	}
+	inode->i_size = bdev_nr_bytes(sb->s_bdev);
+	inode->i_mapping->a_ops = &jfs_metapage_aops;
+	inode_fake_hash(inode);
+	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
+
+	sbi->direct_inode = inode;
+
+	rc = jfs_mount(sb);
+	if (rc) {
+		if (!silent)
+			jfs_err("jfs_mount failed w/return code = %d", rc);
+		goto out_mount_failed;
+	}
+	if (sb_rdonly(sb))
+		sbi->log = NULL;
+	else {
+		rc = jfs_mount_rw(sb, 0);
+		if (rc) {
+			if (!silent) {
+				jfs_err("jfs_mount_rw failed, return code = %d",
+					rc);
+			}
+			goto out_no_rw;
+		}
+	}
+
+	sb->s_magic = JFS_SUPER_MAGIC;
+
+	if (sbi->mntflag & JFS_OS2)
+		sb->s_d_op = &jfs_ci_dentry_operations;
+
+	inode = jfs_iget(sb, ROOT_I);
+	if (IS_ERR(inode)) {
+		ret = PTR_ERR(inode);
+		goto out_no_rw;
+	}
+	sb->s_root = d_make_root(inode);
+	if (!sb->s_root)
+		goto out_no_root;
+
+	/* logical blocks are represented by 40 bits in pxd_t, etc.
+	 * and page cache is indexed by long
+	 */
+	sb->s_maxbytes = min(((loff_t)sb->s_blocksize) << 40, MAX_LFS_FILESIZE);
+	sb->s_time_gran = 1;
+	return 0;
+
+out_no_root:
+	jfs_err("jfs_read_super: get root dentry failed");
+
+out_no_rw:
+	rc = jfs_umount(sb);
+	if (rc)
+		jfs_err("jfs_umount failed with return code %d", rc);
+out_mount_failed:
+	filemap_write_and_wait(sbi->direct_inode->i_mapping);
+	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
+	make_bad_inode(sbi->direct_inode);
+	iput(sbi->direct_inode);
+	sbi->direct_inode = NULL;
+out_unload:
+	unload_nls(sbi->nls_tab);
+out_kfree:
+	kfree(sbi);
+	return ret;
+}
+
+static int jfs_freeze(struct super_block *sb)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct jfs_log *log = sbi->log;
+	int rc = 0;
+
+	if (!sb_rdonly(sb)) {
+		txQuiesce(sb);
+		rc = lmLogShutdown(log);
+		if (rc) {
+			jfs_error(sb, "lmLogShutdown failed\n");
+
+			/* let operations fail rather than hang */
+			txResume(sb);
+
+			return rc;
+		}
+		rc = updateSuper(sb, FM_CLEAN);
+		if (rc) {
+			jfs_err("jfs_freeze: updateSuper failed");
+			/*
+			 * Don't fail here. Everything succeeded except
+			 * marking the superblock clean, so there's really
+			 * no harm in leaving it frozen for now.
+			 */
+		}
+	}
+	return 0;
+}
+
+static int jfs_unfreeze(struct super_block *sb)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	struct jfs_log *log = sbi->log;
+	int rc = 0;
+
+	if (!sb_rdonly(sb)) {
+		rc = updateSuper(sb, FM_MOUNT);
+		if (rc) {
+			jfs_error(sb, "updateSuper failed\n");
+			goto out;
+		}
+		rc = lmLogInit(log);
+		if (rc)
+			jfs_error(sb, "lmLogInit failed\n");
+out:
+		txResume(sb);
+	}
+	return rc;
+}
+
+static struct dentry *jfs_do_mount(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data)
+{
+	return mount_bdev(fs_type, flags, dev_name, data, jfs_fill_super);
+}
+
+static int jfs_sync_fs(struct super_block *sb, int wait)
+{
+	struct jfs_log *log = JFS_SBI(sb)->log;
+
+	/* log == NULL indicates read-only mount */
+	if (log) {
+		/*
+		 * Write quota structures to quota file, sync_blockdev() will
+		 * write them to disk later
+		 */
+		dquot_writeback_dquots(sb, -1);
+		jfs_flush_journal(log, wait);
+		jfs_syncpt(log, 0);
+	}
+
+	return 0;
+}
+
+static int jfs_show_options(struct seq_file *seq, struct dentry *root)
+{
+	struct jfs_sb_info *sbi = JFS_SBI(root->d_sb);
+
+	if (uid_valid(sbi->uid))
+		seq_printf(seq, ",uid=%d", from_kuid(&init_user_ns, sbi->uid));
+	if (gid_valid(sbi->gid))
+		seq_printf(seq, ",gid=%d", from_kgid(&init_user_ns, sbi->gid));
+	if (sbi->umask != -1)
+		seq_printf(seq, ",umask=%03o", sbi->umask);
+	if (sbi->flag & JFS_NOINTEGRITY)
+		seq_puts(seq, ",nointegrity");
+	if (sbi->flag & JFS_DISCARD)
+		seq_printf(seq, ",discard=%u", sbi->minblks_trim);
+	if (sbi->nls_tab)
+		seq_printf(seq, ",iocharset=%s", sbi->nls_tab->charset);
+	if (sbi->flag & JFS_ERR_CONTINUE)
+		seq_printf(seq, ",errors=continue");
+	if (sbi->flag & JFS_ERR_PANIC)
+		seq_printf(seq, ",errors=panic");
+
+#ifdef CONFIG_QUOTA
+	if (sbi->flag & JFS_USRQUOTA)
+		seq_puts(seq, ",usrquota");
+
+	if (sbi->flag & JFS_GRPQUOTA)
+		seq_puts(seq, ",grpquota");
+#endif
+
+	return 0;
+}
+
+#ifdef CONFIG_QUOTA
+
+/* Read data from quotafile - avoid pagecache and such because we cannot afford
+ * acquiring the locks... As quota files are never truncated and quota code
+ * itself serializes the operations (and no one else should touch the files)
+ * we don't have to be afraid of races */
+static ssize_t jfs_quota_read(struct super_block *sb, int type, char *data,
+			      size_t len, loff_t off)
+{
+	struct inode *inode = sb_dqopt(sb)->files[type];
+	sector_t blk = off >> sb->s_blocksize_bits;
+	int err = 0;
+	int offset = off & (sb->s_blocksize - 1);
+	int tocopy;
+	size_t toread;
+	struct buffer_head tmp_bh;
+	struct buffer_head *bh;
+	loff_t i_size = i_size_read(inode);
+
+	if (off > i_size)
+		return 0;
+	if (off+len > i_size)
+		len = i_size-off;
+	toread = len;
+	while (toread > 0) {
+		tocopy = sb->s_blocksize - offset < toread ?
+				sb->s_blocksize - offset : toread;
+
+		tmp_bh.b_state = 0;
+		tmp_bh.b_size = i_blocksize(inode);
+		err = jfs_get_block(inode, blk, &tmp_bh, 0);
+		if (err)
+			return err;
+		if (!buffer_mapped(&tmp_bh))	/* A hole? */
+			memset(data, 0, tocopy);
+		else {
+			bh = sb_bread(sb, tmp_bh.b_blocknr);
+			if (!bh)
+				return -EIO;
+			memcpy(data, bh->b_data+offset, tocopy);
+			brelse(bh);
+		}
+		offset = 0;
+		toread -= tocopy;
+		data += tocopy;
+		blk++;
+	}
+	return len;
+}
+
+/* Write to quotafile */
+static ssize_t jfs_quota_write(struct super_block *sb, int type,
+			       const char *data, size_t len, loff_t off)
+{
+	struct inode *inode = sb_dqopt(sb)->files[type];
+	sector_t blk = off >> sb->s_blocksize_bits;
+	int err = 0;
+	int offset = off & (sb->s_blocksize - 1);
+	int tocopy;
+	size_t towrite = len;
+	struct buffer_head tmp_bh;
+	struct buffer_head *bh;
+
+	inode_lock(inode);
+	while (towrite > 0) {
+		tocopy = sb->s_blocksize - offset < towrite ?
+				sb->s_blocksize - offset : towrite;
+
+		tmp_bh.b_state = 0;
+		tmp_bh.b_size = i_blocksize(inode);
+		err = jfs_get_block(inode, blk, &tmp_bh, 1);
+		if (err)
+			goto out;
+		if (offset || tocopy != sb->s_blocksize)
+			bh = sb_bread(sb, tmp_bh.b_blocknr);
+		else
+			bh = sb_getblk(sb, tmp_bh.b_blocknr);
+		if (!bh) {
+			err = -EIO;
+			goto out;
+		}
+		lock_buffer(bh);
+		memcpy(bh->b_data+offset, data, tocopy);
+		flush_dcache_page(bh->b_page);
+		set_buffer_uptodate(bh);
+		mark_buffer_dirty(bh);
+		unlock_buffer(bh);
+		brelse(bh);
+		offset = 0;
+		towrite -= tocopy;
+		data += tocopy;
+		blk++;
+	}
+out:
+	if (len == towrite) {
+		inode_unlock(inode);
+		return err;
+	}
+	if (inode->i_size < off+len-towrite)
+		i_size_write(inode, off+len-towrite);
+	inode->i_mtime = inode->i_ctime = current_time(inode);
+	mark_inode_dirty(inode);
+	inode_unlock(inode);
+	return len - towrite;
+}
+
+static struct dquot **jfs_get_dquots(struct inode *inode)
+{
+	return JFS_IP(inode)->i_dquot;
+}
+
+static int jfs_quota_on(struct super_block *sb, int type, int format_id,
+			const struct path *path)
+{
+	int err;
+	struct inode *inode;
+
+	err = dquot_quota_on(sb, type, format_id, path);
+	if (err)
+		return err;
+
+	inode = d_inode(path->dentry);
+	inode_lock(inode);
+	JFS_IP(inode)->mode2 |= JFS_NOATIME_FL | JFS_IMMUTABLE_FL;
+	inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
+			S_NOATIME | S_IMMUTABLE);
+	inode_unlock(inode);
+	mark_inode_dirty(inode);
+
+	return 0;
+}
+
+static int jfs_quota_off(struct super_block *sb, int type)
+{
+	struct inode *inode = sb_dqopt(sb)->files[type];
+	int err;
+
+	if (!inode || !igrab(inode))
+		goto out;
+
+	err = dquot_quota_off(sb, type);
+	if (err)
+		goto out_put;
+
+	inode_lock(inode);
+	JFS_IP(inode)->mode2 &= ~(JFS_NOATIME_FL | JFS_IMMUTABLE_FL);
+	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
+	inode_unlock(inode);
+	mark_inode_dirty(inode);
+out_put:
+	iput(inode);
+	return err;
+out:
+	return dquot_quota_off(sb, type);
+}
+#endif
+
+static const struct super_operations jfs_super_operations = {
+	.alloc_inode	= jfs_alloc_inode,
+	.free_inode	= jfs_free_inode,
+	.dirty_inode	= jfs_dirty_inode,
+	.write_inode	= jfs_write_inode,
+	.evict_inode	= jfs_evict_inode,
+	.put_super	= jfs_put_super,
+	.sync_fs	= jfs_sync_fs,
+	.freeze_fs	= jfs_freeze,
+	.unfreeze_fs	= jfs_unfreeze,
+	.statfs		= jfs_statfs,
+	.remount_fs	= jfs_remount,
+	.show_options	= jfs_show_options,
+#ifdef CONFIG_QUOTA
+	.quota_read	= jfs_quota_read,
+	.quota_write	= jfs_quota_write,
+	.get_dquots	= jfs_get_dquots,
+#endif
+};
+
+static const struct export_operations jfs_export_operations = {
+	.fh_to_dentry	= jfs_fh_to_dentry,
+	.fh_to_parent	= jfs_fh_to_parent,
+	.get_parent	= jfs_get_parent,
+};
+
+static struct file_system_type jfs_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "jfs",
+	.mount		= jfs_do_mount,
+	.kill_sb	= kill_block_super,
+	.fs_flags	= FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("jfs");
+
+static void init_once(void *foo)
+{
+	struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;
+
+	memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
+	INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
+	init_rwsem(&jfs_ip->rdwrlock);
+	mutex_init(&jfs_ip->commit_mutex);
+	init_rwsem(&jfs_ip->xattr_sem);
+	spin_lock_init(&jfs_ip->ag_lock);
+	jfs_ip->active_ag = -1;
+	inode_init_once(&jfs_ip->vfs_inode);
+}
+
+static int __init init_jfs_fs(void)
+{
+	int i;
+	int rc;
+
+	jfs_inode_cachep =
+	    kmem_cache_create_usercopy("jfs_ip", sizeof(struct jfs_inode_info),
+			0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|SLAB_ACCOUNT,
+			offsetof(struct jfs_inode_info, i_inline_all),
+			sizeof_field(struct jfs_inode_info, i_inline_all),
+			init_once);
+	if (jfs_inode_cachep == NULL)
+		return -ENOMEM;
+
+	/*
+	 * Metapage initialization
+	 */
+	rc = metapage_init();
+	if (rc) {
+		jfs_err("metapage_init failed w/rc = %d", rc);
+		goto free_slab;
+	}
+
+	/*
+	 * Transaction Manager initialization
+	 */
+	rc = txInit();
+	if (rc) {
+		jfs_err("txInit failed w/rc = %d", rc);
+		goto free_metapage;
+	}
+
+	/*
+	 * I/O completion thread (endio)
+	 */
+	jfsIOthread = kthread_run(jfsIOWait, NULL, "jfsIO");
+	if (IS_ERR(jfsIOthread)) {
+		rc = PTR_ERR(jfsIOthread);
+		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
+		goto end_txmngr;
+	}
+
+	if (commit_threads < 1)
+		commit_threads = num_online_cpus();
+	if (commit_threads > MAX_COMMIT_THREADS)
+		commit_threads = MAX_COMMIT_THREADS;
+
+	for (i = 0; i < commit_threads; i++) {
+		jfsCommitThread[i] = kthread_run(jfs_lazycommit, NULL,
+						 "jfsCommit");
+		if (IS_ERR(jfsCommitThread[i])) {
+			rc = PTR_ERR(jfsCommitThread[i]);
+			jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
+			commit_threads = i;
+			goto kill_committask;
+		}
+	}
+
+	jfsSyncThread = kthread_run(jfs_sync, NULL, "jfsSync");
+	if (IS_ERR(jfsSyncThread)) {
+		rc = PTR_ERR(jfsSyncThread);
+		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
+		goto kill_committask;
+	}
+
+#ifdef PROC_FS_JFS
+	jfs_proc_init();
+#endif
+
+	rc = register_filesystem(&jfs_fs_type);
+	if (!rc)
+		return 0;
+
+#ifdef PROC_FS_JFS
+	jfs_proc_clean();
+#endif
+	kthread_stop(jfsSyncThread);
+kill_committask:
+	for (i = 0; i < commit_threads; i++)
+		kthread_stop(jfsCommitThread[i]);
+	kthread_stop(jfsIOthread);
+end_txmngr:
+	txExit();
+free_metapage:
+	metapage_exit();
+free_slab:
+	kmem_cache_destroy(jfs_inode_cachep);
+	return rc;
+}
+
+static void __exit exit_jfs_fs(void)
+{
+	int i;
+
+	jfs_info("exit_jfs_fs called");
+
+	txExit();
+	metapage_exit();
+
+	kthread_stop(jfsIOthread);
+	for (i = 0; i < commit_threads; i++)
+		kthread_stop(jfsCommitThread[i]);
+	kthread_stop(jfsSyncThread);
+#ifdef PROC_FS_JFS
+	jfs_proc_clean();
+#endif
+	unregister_filesystem(&jfs_fs_type);
+
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+	kmem_cache_destroy(jfs_inode_cachep);
+}
+
+module_init(init_jfs_fs)
+module_exit(exit_jfs_fs)
diff --git a/fs/jfs/symlink.c b/fs/jfs/symlink.c
new file mode 100644
index 000000000..a040719aa
--- /dev/null
+++ b/fs/jfs/symlink.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) Christoph Hellwig, 2001-2002
+ */
+
+#include <linux/fs.h>
+#include "jfs_incore.h"
+#include "jfs_inode.h"
+#include "jfs_xattr.h"
+
+const struct inode_operations jfs_fast_symlink_inode_operations = {
+	.get_link	= simple_get_link,
+	.setattr	= jfs_setattr,
+	.listxattr	= jfs_listxattr,
+};
+
+const struct inode_operations jfs_symlink_inode_operations = {
+	.get_link	= page_get_link,
+	.setattr	= jfs_setattr,
+	.listxattr	= jfs_listxattr,
+};
+
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
new file mode 100644
index 000000000..f9273f690
--- /dev/null
+++ b/fs/jfs/xattr.c
@@ -0,0 +1,1035 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) International Business Machines  Corp., 2000-2004
+ *   Copyright (C) Christoph Hellwig, 2002
+ */
+
+#include <linux/capability.h>
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/posix_acl_xattr.h>
+#include <linux/slab.h>
+#include <linux/quotaops.h>
+#include <linux/security.h>
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_dmap.h"
+#include "jfs_debug.h"
+#include "jfs_dinode.h"
+#include "jfs_extent.h"
+#include "jfs_metapage.h"
+#include "jfs_xattr.h"
+#include "jfs_acl.h"
+
+/*
+ *	jfs_xattr.c: extended attribute service
+ *
+ * Overall design --
+ *
+ * Format:
+ *
+ *   Extended attribute lists (jfs_ea_list) consist of an overall size (32 bit
+ *   value) and a variable (0 or more) number of extended attribute
+ *   entries.  Each extended attribute entry (jfs_ea) is a <name,value> double
+ *   where <name> is constructed from a null-terminated ascii string
+ *   (1 ... 255 bytes in the name) and <value> is arbitrary 8 bit data
+ *   (1 ... 65535 bytes).  The in-memory format is
+ *
+ *   0       1        2        4                4 + namelen + 1
+ *   +-------+--------+--------+----------------+-------------------+
+ *   | Flags | Name   | Value  | Name String \0 | Data . . . .      |
+ *   |       | Length | Length |                |                   |
+ *   +-------+--------+--------+----------------+-------------------+
+ *
+ *   A jfs_ea_list then is structured as
+ *
+ *   0            4                   4 + EA_SIZE(ea1)
+ *   +------------+-------------------+--------------------+-----
+ *   | Overall EA | First FEA Element | Second FEA Element | .....
+ *   | List Size  |                   |                    |
+ *   +------------+-------------------+--------------------+-----
+ *
+ *   On-disk:
+ *
+ *	FEALISTs are stored on disk using blocks allocated by dbAlloc() and
+ *	written directly. An EA list may be in-lined in the inode if there is
+ *	sufficient room available.
+ */
+
+struct ea_buffer {
+	int flag;		/* Indicates what storage xattr points to */
+	int max_size;		/* largest xattr that fits in current buffer */
+	dxd_t new_ea;		/* dxd to replace ea when modifying xattr */
+	struct metapage *mp;	/* metapage containing ea list */
+	struct jfs_ea_list *xattr;	/* buffer containing ea list */
+};
+
+/*
+ * ea_buffer.flag values
+ */
+#define EA_INLINE	0x0001
+#define EA_EXTENT	0x0002
+#define EA_NEW		0x0004
+#define EA_MALLOC	0x0008
+
+
+/*
+ * Mapping of on-disk attribute names: for on-disk attribute names with an
+ * unknown prefix (not "system.", "user.", "security.", or "trusted."), the
+ * prefix "os2." is prepended.  On the way back to disk, "os2." prefixes are
+ * stripped and we make sure that the remaining name does not start with one
+ * of the know prefixes.
+ */
+
+static int is_known_namespace(const char *name)
+{
+	if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
+	    strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
+	    strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
+	    strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
+		return false;
+
+	return true;
+}
+
+static inline int name_size(struct jfs_ea *ea)
+{
+	if (is_known_namespace(ea->name))
+		return ea->namelen;
+	else
+		return ea->namelen + XATTR_OS2_PREFIX_LEN;
+}
+
+static inline int copy_name(char *buffer, struct jfs_ea *ea)
+{
+	int len = ea->namelen;
+
+	if (!is_known_namespace(ea->name)) {
+		memcpy(buffer, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN);
+		buffer += XATTR_OS2_PREFIX_LEN;
+		len += XATTR_OS2_PREFIX_LEN;
+	}
+	memcpy(buffer, ea->name, ea->namelen);
+	buffer[ea->namelen] = 0;
+
+	return len;
+}
+
+/* Forward references */
+static void ea_release(struct inode *inode, struct ea_buffer *ea_buf);
+
+/*
+ * NAME: ea_write_inline
+ *
+ * FUNCTION: Attempt to write an EA inline if area is available
+ *
+ * PRE CONDITIONS:
+ *	Already verified that the specified EA is small enough to fit inline
+ *
+ * PARAMETERS:
+ *	ip	- Inode pointer
+ *	ealist	- EA list pointer
+ *	size	- size of ealist in bytes
+ *	ea	- dxd_t structure to be filled in with necessary EA information
+ *		  if we successfully copy the EA inline
+ *
+ * NOTES:
+ *	Checks if the inode's inline area is available.  If so, copies EA inline
+ *	and sets <ea> fields appropriately.  Otherwise, returns failure, EA will
+ *	have to be put into an extent.
+ *
+ * RETURNS: 0 for successful copy to inline area; -1 if area not available
+ */
+static int ea_write_inline(struct inode *ip, struct jfs_ea_list *ealist,
+			   int size, dxd_t * ea)
+{
+	struct jfs_inode_info *ji = JFS_IP(ip);
+
+	/*
+	 * Make sure we have an EA -- the NULL EA list is valid, but you
+	 * can't copy it!
+	 */
+	if (ealist && size > sizeof (struct jfs_ea_list)) {
+		assert(size <= sizeof (ji->i_inline_ea));
+
+		/*
+		 * See if the space is available or if it is already being
+		 * used for an inline EA.
+		 */
+		if (!(ji->mode2 & INLINEEA) && !(ji->ea.flag & DXD_INLINE))
+			return -EPERM;
+
+		DXDsize(ea, size);
+		DXDlength(ea, 0);
+		DXDaddress(ea, 0);
+		memcpy(ji->i_inline_ea, ealist, size);
+		ea->flag = DXD_INLINE;
+		ji->mode2 &= ~INLINEEA;
+	} else {
+		ea->flag = 0;
+		DXDsize(ea, 0);
+		DXDlength(ea, 0);
+		DXDaddress(ea, 0);
+
+		/* Free up INLINE area */
+		if (ji->ea.flag & DXD_INLINE)
+			ji->mode2 |= INLINEEA;
+	}
+
+	return 0;
+}
+
+/*
+ * NAME: ea_write
+ *
+ * FUNCTION: Write an EA for an inode
+ *
+ * PRE CONDITIONS: EA has been verified
+ *
+ * PARAMETERS:
+ *	ip	- Inode pointer
+ *	ealist	- EA list pointer
+ *	size	- size of ealist in bytes
+ *	ea	- dxd_t structure to be filled in appropriately with where the
+ *		  EA was copied
+ *
+ * NOTES: Will write EA inline if able to, otherwise allocates blocks for an
+ *	extent and synchronously writes it to those blocks.
+ *
+ * RETURNS: 0 for success; Anything else indicates failure
+ */
+static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size,
+		       dxd_t * ea)
+{
+	struct super_block *sb = ip->i_sb;
+	struct jfs_inode_info *ji = JFS_IP(ip);
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	int nblocks;
+	s64 blkno;
+	int rc = 0, i;
+	char *cp;
+	s32 nbytes, nb;
+	s32 bytes_to_write;
+	struct metapage *mp;
+
+	/*
+	 * Quick check to see if this is an in-linable EA.  Short EAs
+	 * and empty EAs are all in-linable, provided the space exists.
+	 */
+	if (!ealist || size <= sizeof (ji->i_inline_ea)) {
+		if (!ea_write_inline(ip, ealist, size, ea))
+			return 0;
+	}
+
+	/* figure out how many blocks we need */
+	nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits;
+
+	/* Allocate new blocks to quota. */
+	rc = dquot_alloc_block(ip, nblocks);
+	if (rc)
+		return rc;
+
+	rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno);
+	if (rc) {
+		/*Rollback quota allocation. */
+		dquot_free_block(ip, nblocks);
+		return rc;
+	}
+
+	/*
+	 * Now have nblocks worth of storage to stuff into the FEALIST.
+	 * loop over the FEALIST copying data into the buffer one page at
+	 * a time.
+	 */
+	cp = (char *) ealist;
+	nbytes = size;
+	for (i = 0; i < nblocks; i += sbi->nbperpage) {
+		/*
+		 * Determine how many bytes for this request, and round up to
+		 * the nearest aggregate block size
+		 */
+		nb = min(PSIZE, nbytes);
+		bytes_to_write =
+		    ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
+		    << sb->s_blocksize_bits;
+
+		if (!(mp = get_metapage(ip, blkno + i, bytes_to_write, 1))) {
+			rc = -EIO;
+			goto failed;
+		}
+
+		memcpy(mp->data, cp, nb);
+
+		/*
+		 * We really need a way to propagate errors for
+		 * forced writes like this one.  --hch
+		 *
+		 * (__write_metapage => release_metapage => flush_metapage)
+		 */
+#ifdef _JFS_FIXME
+		if ((rc = flush_metapage(mp))) {
+			/*
+			 * the write failed -- this means that the buffer
+			 * is still assigned and the blocks are not being
+			 * used.  this seems like the best error recovery
+			 * we can get ...
+			 */
+			goto failed;
+		}
+#else
+		flush_metapage(mp);
+#endif
+
+		cp += PSIZE;
+		nbytes -= nb;
+	}
+
+	ea->flag = DXD_EXTENT;
+	DXDsize(ea, le32_to_cpu(ealist->size));
+	DXDlength(ea, nblocks);
+	DXDaddress(ea, blkno);
+
+	/* Free up INLINE area */
+	if (ji->ea.flag & DXD_INLINE)
+		ji->mode2 |= INLINEEA;
+
+	return 0;
+
+      failed:
+	/* Rollback quota allocation. */
+	dquot_free_block(ip, nblocks);
+
+	dbFree(ip, blkno, nblocks);
+	return rc;
+}
+
+/*
+ * NAME: ea_read_inline
+ *
+ * FUNCTION: Read an inlined EA into user's buffer
+ *
+ * PARAMETERS:
+ *	ip	- Inode pointer
+ *	ealist	- Pointer to buffer to fill in with EA
+ *
+ * RETURNS: 0
+ */
+static int ea_read_inline(struct inode *ip, struct jfs_ea_list *ealist)
+{
+	struct jfs_inode_info *ji = JFS_IP(ip);
+	int ea_size = sizeDXD(&ji->ea);
+
+	if (ea_size == 0) {
+		ealist->size = 0;
+		return 0;
+	}
+
+	/* Sanity Check */
+	if ((sizeDXD(&ji->ea) > sizeof (ji->i_inline_ea)))
+		return -EIO;
+	if (le32_to_cpu(((struct jfs_ea_list *) &ji->i_inline_ea)->size)
+	    != ea_size)
+		return -EIO;
+
+	memcpy(ealist, ji->i_inline_ea, ea_size);
+	return 0;
+}
+
+/*
+ * NAME: ea_read
+ *
+ * FUNCTION: copy EA data into user's buffer
+ *
+ * PARAMETERS:
+ *	ip	- Inode pointer
+ *	ealist	- Pointer to buffer to fill in with EA
+ *
+ * NOTES:  If EA is inline calls ea_read_inline() to copy EA.
+ *
+ * RETURNS: 0 for success; other indicates failure
+ */
+static int ea_read(struct inode *ip, struct jfs_ea_list *ealist)
+{
+	struct super_block *sb = ip->i_sb;
+	struct jfs_inode_info *ji = JFS_IP(ip);
+	struct jfs_sb_info *sbi = JFS_SBI(sb);
+	int nblocks;
+	s64 blkno;
+	char *cp = (char *) ealist;
+	int i;
+	int nbytes, nb;
+	s32 bytes_to_read;
+	struct metapage *mp;
+
+	/* quick check for in-line EA */
+	if (ji->ea.flag & DXD_INLINE)
+		return ea_read_inline(ip, ealist);
+
+	nbytes = sizeDXD(&ji->ea);
+	if (!nbytes) {
+		jfs_error(sb, "nbytes is 0\n");
+		return -EIO;
+	}
+
+	/*
+	 * Figure out how many blocks were allocated when this EA list was
+	 * originally written to disk.
+	 */
+	nblocks = lengthDXD(&ji->ea) << sbi->l2nbperpage;
+	blkno = addressDXD(&ji->ea) << sbi->l2nbperpage;
+
+	/*
+	 * I have found the disk blocks which were originally used to store
+	 * the FEALIST.  now i loop over each contiguous block copying the
+	 * data into the buffer.
+	 */
+	for (i = 0; i < nblocks; i += sbi->nbperpage) {
+		/*
+		 * Determine how many bytes for this request, and round up to
+		 * the nearest aggregate block size
+		 */
+		nb = min(PSIZE, nbytes);
+		bytes_to_read =
+		    ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
+		    << sb->s_blocksize_bits;
+
+		if (!(mp = read_metapage(ip, blkno + i, bytes_to_read, 1)))
+			return -EIO;
+
+		memcpy(cp, mp->data, nb);
+		release_metapage(mp);
+
+		cp += PSIZE;
+		nbytes -= nb;
+	}
+
+	return 0;
+}
+
+/*
+ * NAME: ea_get
+ *
+ * FUNCTION: Returns buffer containing existing extended attributes.
+ *	     The size of the buffer will be the larger of the existing
+ *	     attributes size, or min_size.
+ *
+ *	     The buffer, which may be inlined in the inode or in the
+ *	     page cache must be release by calling ea_release or ea_put
+ *
+ * PARAMETERS:
+ *	inode	- Inode pointer
+ *	ea_buf	- Structure to be populated with ealist and its metadata
+ *	min_size- minimum size of buffer to be returned
+ *
+ * RETURNS: 0 for success; Other indicates failure
+ */
+static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size)
+{
+	struct jfs_inode_info *ji = JFS_IP(inode);
+	struct super_block *sb = inode->i_sb;
+	int size;
+	int ea_size = sizeDXD(&ji->ea);
+	int blocks_needed, current_blocks;
+	s64 blkno;
+	int rc;
+	int quota_allocation = 0;
+
+	/* When fsck.jfs clears a bad ea, it doesn't clear the size */
+	if (ji->ea.flag == 0)
+		ea_size = 0;
+
+	if (ea_size == 0) {
+		if (min_size == 0) {
+			ea_buf->flag = 0;
+			ea_buf->max_size = 0;
+			ea_buf->xattr = NULL;
+			return 0;
+		}
+		if ((min_size <= sizeof (ji->i_inline_ea)) &&
+		    (ji->mode2 & INLINEEA)) {
+			ea_buf->flag = EA_INLINE | EA_NEW;
+			ea_buf->max_size = sizeof (ji->i_inline_ea);
+			ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
+			DXDlength(&ea_buf->new_ea, 0);
+			DXDaddress(&ea_buf->new_ea, 0);
+			ea_buf->new_ea.flag = DXD_INLINE;
+			DXDsize(&ea_buf->new_ea, min_size);
+			return 0;
+		}
+		current_blocks = 0;
+	} else if (ji->ea.flag & DXD_INLINE) {
+		if (min_size <= sizeof (ji->i_inline_ea)) {
+			ea_buf->flag = EA_INLINE;
+			ea_buf->max_size = sizeof (ji->i_inline_ea);
+			ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
+			goto size_check;
+		}
+		current_blocks = 0;
+	} else {
+		if (!(ji->ea.flag & DXD_EXTENT)) {
+			jfs_error(sb, "invalid ea.flag\n");
+			return -EIO;
+		}
+		current_blocks = (ea_size + sb->s_blocksize - 1) >>
+		    sb->s_blocksize_bits;
+	}
+	size = max(min_size, ea_size);
+
+	if (size > PSIZE) {
+		/*
+		 * To keep the rest of the code simple.  Allocate a
+		 * contiguous buffer to work with. Make the buffer large
+		 * enough to make use of the whole extent.
+		 */
+		ea_buf->max_size = (size + sb->s_blocksize - 1) &
+		    ~(sb->s_blocksize - 1);
+
+		ea_buf->xattr = kmalloc(ea_buf->max_size, GFP_KERNEL);
+		if (ea_buf->xattr == NULL)
+			return -ENOMEM;
+
+		ea_buf->flag = EA_MALLOC;
+
+		if (ea_size == 0)
+			return 0;
+
+		if ((rc = ea_read(inode, ea_buf->xattr))) {
+			kfree(ea_buf->xattr);
+			ea_buf->xattr = NULL;
+			return rc;
+		}
+		goto size_check;
+	}
+	blocks_needed = (min_size + sb->s_blocksize - 1) >>
+	    sb->s_blocksize_bits;
+
+	if (blocks_needed > current_blocks) {
+		/* Allocate new blocks to quota. */
+		rc = dquot_alloc_block(inode, blocks_needed);
+		if (rc)
+			return -EDQUOT;
+
+		quota_allocation = blocks_needed;
+
+		rc = dbAlloc(inode, INOHINT(inode), (s64) blocks_needed,
+			     &blkno);
+		if (rc)
+			goto clean_up;
+
+		DXDlength(&ea_buf->new_ea, blocks_needed);
+		DXDaddress(&ea_buf->new_ea, blkno);
+		ea_buf->new_ea.flag = DXD_EXTENT;
+		DXDsize(&ea_buf->new_ea, min_size);
+
+		ea_buf->flag = EA_EXTENT | EA_NEW;
+
+		ea_buf->mp = get_metapage(inode, blkno,
+					  blocks_needed << sb->s_blocksize_bits,
+					  1);
+		if (ea_buf->mp == NULL) {
+			dbFree(inode, blkno, (s64) blocks_needed);
+			rc = -EIO;
+			goto clean_up;
+		}
+		ea_buf->xattr = ea_buf->mp->data;
+		ea_buf->max_size = (min_size + sb->s_blocksize - 1) &
+		    ~(sb->s_blocksize - 1);
+		if (ea_size == 0)
+			return 0;
+		if ((rc = ea_read(inode, ea_buf->xattr))) {
+			discard_metapage(ea_buf->mp);
+			dbFree(inode, blkno, (s64) blocks_needed);
+			goto clean_up;
+		}
+		goto size_check;
+	}
+	ea_buf->flag = EA_EXTENT;
+	ea_buf->mp = read_metapage(inode, addressDXD(&ji->ea),
+				   lengthDXD(&ji->ea) << sb->s_blocksize_bits,
+				   1);
+	if (ea_buf->mp == NULL) {
+		rc = -EIO;
+		goto clean_up;
+	}
+	ea_buf->xattr = ea_buf->mp->data;
+	ea_buf->max_size = (ea_size + sb->s_blocksize - 1) &
+	    ~(sb->s_blocksize - 1);
+
+      size_check:
+	if (EALIST_SIZE(ea_buf->xattr) != ea_size) {
+		printk(KERN_ERR "ea_get: invalid extended attribute\n");
+		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1,
+				     ea_buf->xattr, ea_size, 1);
+		ea_release(inode, ea_buf);
+		rc = -EIO;
+		goto clean_up;
+	}
+
+	return ea_size;
+
+      clean_up:
+	/* Rollback quota allocation */
+	if (quota_allocation)
+		dquot_free_block(inode, quota_allocation);
+
+	return (rc);
+}
+
+static void ea_release(struct inode *inode, struct ea_buffer *ea_buf)
+{
+	if (ea_buf->flag & EA_MALLOC)
+		kfree(ea_buf->xattr);
+	else if (ea_buf->flag & EA_EXTENT) {
+		assert(ea_buf->mp);
+		release_metapage(ea_buf->mp);
+
+		if (ea_buf->flag & EA_NEW)
+			dbFree(inode, addressDXD(&ea_buf->new_ea),
+			       lengthDXD(&ea_buf->new_ea));
+	}
+}
+
+static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf,
+		  int new_size)
+{
+	struct jfs_inode_info *ji = JFS_IP(inode);
+	unsigned long old_blocks, new_blocks;
+	int rc = 0;
+
+	if (new_size == 0) {
+		ea_release(inode, ea_buf);
+		ea_buf = NULL;
+	} else if (ea_buf->flag & EA_INLINE) {
+		assert(new_size <= sizeof (ji->i_inline_ea));
+		ji->mode2 &= ~INLINEEA;
+		ea_buf->new_ea.flag = DXD_INLINE;
+		DXDsize(&ea_buf->new_ea, new_size);
+		DXDaddress(&ea_buf->new_ea, 0);
+		DXDlength(&ea_buf->new_ea, 0);
+	} else if (ea_buf->flag & EA_MALLOC) {
+		rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
+		kfree(ea_buf->xattr);
+	} else if (ea_buf->flag & EA_NEW) {
+		/* We have already allocated a new dxd */
+		flush_metapage(ea_buf->mp);
+	} else {
+		/* ->xattr must point to original ea's metapage */
+		rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
+		discard_metapage(ea_buf->mp);
+	}
+	if (rc)
+		return rc;
+
+	old_blocks = new_blocks = 0;
+
+	if (ji->ea.flag & DXD_EXTENT) {
+		invalidate_dxd_metapages(inode, ji->ea);
+		old_blocks = lengthDXD(&ji->ea);
+	}
+
+	if (ea_buf) {
+		txEA(tid, inode, &ji->ea, &ea_buf->new_ea);
+		if (ea_buf->new_ea.flag & DXD_EXTENT) {
+			new_blocks = lengthDXD(&ea_buf->new_ea);
+			if (ji->ea.flag & DXD_INLINE)
+				ji->mode2 |= INLINEEA;
+		}
+		ji->ea = ea_buf->new_ea;
+	} else {
+		txEA(tid, inode, &ji->ea, NULL);
+		if (ji->ea.flag & DXD_INLINE)
+			ji->mode2 |= INLINEEA;
+		ji->ea.flag = 0;
+		ji->ea.size = 0;
+	}
+
+	/* If old blocks exist, they must be removed from quota allocation. */
+	if (old_blocks)
+		dquot_free_block(inode, old_blocks);
+
+	inode->i_ctime = current_time(inode);
+
+	return 0;
+}
+
+int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name,
+		   const void *value, size_t value_len, int flags)
+{
+	struct jfs_ea_list *ealist;
+	struct jfs_ea *ea, *old_ea = NULL, *next_ea = NULL;
+	struct ea_buffer ea_buf;
+	int old_ea_size = 0;
+	int xattr_size;
+	int new_size;
+	int namelen = strlen(name);
+	int found = 0;
+	int rc;
+	int length;
+
+	down_write(&JFS_IP(inode)->xattr_sem);
+
+	xattr_size = ea_get(inode, &ea_buf, 0);
+	if (xattr_size < 0) {
+		rc = xattr_size;
+		goto out;
+	}
+
+      again:
+	ealist = (struct jfs_ea_list *) ea_buf.xattr;
+	new_size = sizeof (struct jfs_ea_list);
+
+	if (xattr_size) {
+		for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist);
+		     ea = NEXT_EA(ea)) {
+			if ((namelen == ea->namelen) &&
+			    (memcmp(name, ea->name, namelen) == 0)) {
+				found = 1;
+				if (flags & XATTR_CREATE) {
+					rc = -EEXIST;
+					goto release;
+				}
+				old_ea = ea;
+				old_ea_size = EA_SIZE(ea);
+				next_ea = NEXT_EA(ea);
+			} else
+				new_size += EA_SIZE(ea);
+		}
+	}
+
+	if (!found) {
+		if (flags & XATTR_REPLACE) {
+			rc = -ENODATA;
+			goto release;
+		}
+		if (value == NULL) {
+			rc = 0;
+			goto release;
+		}
+	}
+	if (value)
+		new_size += sizeof (struct jfs_ea) + namelen + 1 + value_len;
+
+	if (new_size > ea_buf.max_size) {
+		/*
+		 * We need to allocate more space for merged ea list.
+		 * We should only have loop to again: once.
+		 */
+		ea_release(inode, &ea_buf);
+		xattr_size = ea_get(inode, &ea_buf, new_size);
+		if (xattr_size < 0) {
+			rc = xattr_size;
+			goto out;
+		}
+		goto again;
+	}
+
+	/* Remove old ea of the same name */
+	if (found) {
+		/* number of bytes following target EA */
+		length = (char *) END_EALIST(ealist) - (char *) next_ea;
+		if (length > 0)
+			memmove(old_ea, next_ea, length);
+		xattr_size -= old_ea_size;
+	}
+
+	/* Add new entry to the end */
+	if (value) {
+		if (xattr_size == 0)
+			/* Completely new ea list */
+			xattr_size = sizeof (struct jfs_ea_list);
+
+		/*
+		 * The size of EA value is limitted by on-disk format up to
+		 *  __le16, there would be an overflow if the size is equal
+		 * to XATTR_SIZE_MAX (65536).  In order to avoid this issue,
+		 * we can pre-checkup the value size against USHRT_MAX, and
+		 * return -E2BIG in this case, which is consistent with the
+		 * VFS setxattr interface.
+		 */
+		if (value_len >= USHRT_MAX) {
+			rc = -E2BIG;
+			goto release;
+		}
+
+		ea = (struct jfs_ea *) ((char *) ealist + xattr_size);
+		ea->flag = 0;
+		ea->namelen = namelen;
+		ea->valuelen = (cpu_to_le16(value_len));
+		memcpy(ea->name, name, namelen);
+		ea->name[namelen] = 0;
+		if (value_len)
+			memcpy(&ea->name[namelen + 1], value, value_len);
+		xattr_size += EA_SIZE(ea);
+	}
+
+	/* DEBUG - If we did this right, these number match */
+	if (xattr_size != new_size) {
+		printk(KERN_ERR
+		       "__jfs_setxattr: xattr_size = %d, new_size = %d\n",
+		       xattr_size, new_size);
+
+		rc = -EINVAL;
+		goto release;
+	}
+
+	/*
+	 * If we're left with an empty list, there's no ea
+	 */
+	if (new_size == sizeof (struct jfs_ea_list))
+		new_size = 0;
+
+	ealist->size = cpu_to_le32(new_size);
+
+	rc = ea_put(tid, inode, &ea_buf, new_size);
+
+	goto out;
+      release:
+	ea_release(inode, &ea_buf);
+      out:
+	up_write(&JFS_IP(inode)->xattr_sem);
+
+	return rc;
+}
+
+ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data,
+		       size_t buf_size)
+{
+	struct jfs_ea_list *ealist;
+	struct jfs_ea *ea;
+	struct ea_buffer ea_buf;
+	int xattr_size;
+	ssize_t size;
+	int namelen = strlen(name);
+	char *value;
+
+	down_read(&JFS_IP(inode)->xattr_sem);
+
+	xattr_size = ea_get(inode, &ea_buf, 0);
+
+	if (xattr_size < 0) {
+		size = xattr_size;
+		goto out;
+	}
+
+	if (xattr_size == 0)
+		goto not_found;
+
+	ealist = (struct jfs_ea_list *) ea_buf.xattr;
+
+	/* Find the named attribute */
+	for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea))
+		if ((namelen == ea->namelen) &&
+		    memcmp(name, ea->name, namelen) == 0) {
+			/* Found it */
+			size = le16_to_cpu(ea->valuelen);
+			if (!data)
+				goto release;
+			else if (size > buf_size) {
+				size = -ERANGE;
+				goto release;
+			}
+			value = ((char *) &ea->name) + ea->namelen + 1;
+			memcpy(data, value, size);
+			goto release;
+		}
+      not_found:
+	size = -ENODATA;
+      release:
+	ea_release(inode, &ea_buf);
+      out:
+	up_read(&JFS_IP(inode)->xattr_sem);
+
+	return size;
+}
+
+/*
+ * No special permissions are needed to list attributes except for trusted.*
+ */
+static inline int can_list(struct jfs_ea *ea)
+{
+	return (strncmp(ea->name, XATTR_TRUSTED_PREFIX,
+			    XATTR_TRUSTED_PREFIX_LEN) ||
+		capable(CAP_SYS_ADMIN));
+}
+
+ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size)
+{
+	struct inode *inode = d_inode(dentry);
+	char *buffer;
+	ssize_t size = 0;
+	int xattr_size;
+	struct jfs_ea_list *ealist;
+	struct jfs_ea *ea;
+	struct ea_buffer ea_buf;
+
+	down_read(&JFS_IP(inode)->xattr_sem);
+
+	xattr_size = ea_get(inode, &ea_buf, 0);
+	if (xattr_size < 0) {
+		size = xattr_size;
+		goto out;
+	}
+
+	if (xattr_size == 0)
+		goto release;
+
+	ealist = (struct jfs_ea_list *) ea_buf.xattr;
+
+	/* compute required size of list */
+	for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) {
+		if (can_list(ea))
+			size += name_size(ea) + 1;
+	}
+
+	if (!data)
+		goto release;
+
+	if (size > buf_size) {
+		size = -ERANGE;
+		goto release;
+	}
+
+	/* Copy attribute names to buffer */
+	buffer = data;
+	for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) {
+		if (can_list(ea)) {
+			int namelen = copy_name(buffer, ea);
+			buffer += namelen + 1;
+		}
+	}
+
+      release:
+	ea_release(inode, &ea_buf);
+      out:
+	up_read(&JFS_IP(inode)->xattr_sem);
+	return size;
+}
+
+static int __jfs_xattr_set(struct inode *inode, const char *name,
+			   const void *value, size_t size, int flags)
+{
+	struct jfs_inode_info *ji = JFS_IP(inode);
+	tid_t tid;
+	int rc;
+
+	tid = txBegin(inode->i_sb, 0);
+	mutex_lock(&ji->commit_mutex);
+	rc = __jfs_setxattr(tid, inode, name, value, size, flags);
+	if (!rc)
+		rc = txCommit(tid, 1, &inode, 0);
+	txEnd(tid);
+	mutex_unlock(&ji->commit_mutex);
+
+	return rc;
+}
+
+static int jfs_xattr_get(const struct xattr_handler *handler,
+			 struct dentry *unused, struct inode *inode,
+			 const char *name, void *value, size_t size)
+{
+	name = xattr_full_name(handler, name);
+	return __jfs_getxattr(inode, name, value, size);
+}
+
+static int jfs_xattr_set(const struct xattr_handler *handler,
+			 struct user_namespace *mnt_userns,
+			 struct dentry *unused, struct inode *inode,
+			 const char *name, const void *value,
+			 size_t size, int flags)
+{
+	name = xattr_full_name(handler, name);
+	return __jfs_xattr_set(inode, name, value, size, flags);
+}
+
+static int jfs_xattr_get_os2(const struct xattr_handler *handler,
+			     struct dentry *unused, struct inode *inode,
+			     const char *name, void *value, size_t size)
+{
+	if (is_known_namespace(name))
+		return -EOPNOTSUPP;
+	return __jfs_getxattr(inode, name, value, size);
+}
+
+static int jfs_xattr_set_os2(const struct xattr_handler *handler,
+			     struct user_namespace *mnt_userns,
+			     struct dentry *unused, struct inode *inode,
+			     const char *name, const void *value,
+			     size_t size, int flags)
+{
+	if (is_known_namespace(name))
+		return -EOPNOTSUPP;
+	return __jfs_xattr_set(inode, name, value, size, flags);
+}
+
+static const struct xattr_handler jfs_user_xattr_handler = {
+	.prefix = XATTR_USER_PREFIX,
+	.get = jfs_xattr_get,
+	.set = jfs_xattr_set,
+};
+
+static const struct xattr_handler jfs_os2_xattr_handler = {
+	.prefix = XATTR_OS2_PREFIX,
+	.get = jfs_xattr_get_os2,
+	.set = jfs_xattr_set_os2,
+};
+
+static const struct xattr_handler jfs_security_xattr_handler = {
+	.prefix = XATTR_SECURITY_PREFIX,
+	.get = jfs_xattr_get,
+	.set = jfs_xattr_set,
+};
+
+static const struct xattr_handler jfs_trusted_xattr_handler = {
+	.prefix = XATTR_TRUSTED_PREFIX,
+	.get = jfs_xattr_get,
+	.set = jfs_xattr_set,
+};
+
+const struct xattr_handler *jfs_xattr_handlers[] = {
+#ifdef CONFIG_JFS_POSIX_ACL
+	&posix_acl_access_xattr_handler,
+	&posix_acl_default_xattr_handler,
+#endif
+	&jfs_os2_xattr_handler,
+	&jfs_user_xattr_handler,
+	&jfs_security_xattr_handler,
+	&jfs_trusted_xattr_handler,
+	NULL,
+};
+
+
+#ifdef CONFIG_JFS_SECURITY
+static int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+			  void *fs_info)
+{
+	const struct xattr *xattr;
+	tid_t *tid = fs_info;
+	char *name;
+	int err = 0;
+
+	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+		name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
+			       strlen(xattr->name) + 1, GFP_NOFS);
+		if (!name) {
+			err = -ENOMEM;
+			break;
+		}
+		strcpy(name, XATTR_SECURITY_PREFIX);
+		strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
+
+		err = __jfs_setxattr(*tid, inode, name,
+				     xattr->value, xattr->value_len, 0);
+		kfree(name);
+		if (err < 0)
+			break;
+	}
+	return err;
+}
+
+int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir,
+		      const struct qstr *qstr)
+{
+	return security_inode_init_security(inode, dir, qstr,
+					    &jfs_initxattrs, &tid);
+}
+#endif