Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 1624 insertions, 0 deletions

diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
new file mode 100644
index 0000000000..5f4ebe279a
--- /dev/null
+++ b/fs/gfs2/super.c
@@ -0,0 +1,1624 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
+ * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/bio.h>
+#include <linux/sched/signal.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/statfs.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/crc32.h>
+#include <linux/time.h>
+#include <linux/wait.h>
+#include <linux/writeback.h>
+#include <linux/backing-dev.h>
+#include <linux/kernel.h>
+
+#include "gfs2.h"
+#include "incore.h"
+#include "bmap.h"
+#include "dir.h"
+#include "glock.h"
+#include "glops.h"
+#include "inode.h"
+#include "log.h"
+#include "meta_io.h"
+#include "quota.h"
+#include "recovery.h"
+#include "rgrp.h"
+#include "super.h"
+#include "trans.h"
+#include "util.h"
+#include "sys.h"
+#include "xattr.h"
+#include "lops.h"
+
+enum dinode_demise {
+	SHOULD_DELETE_DINODE,
+	SHOULD_NOT_DELETE_DINODE,
+	SHOULD_DEFER_EVICTION,
+};
+
+/**
+ * gfs2_jindex_free - Clear all the journal index information
+ * @sdp: The GFS2 superblock
+ *
+ */
+
+void gfs2_jindex_free(struct gfs2_sbd *sdp)
+{
+	struct list_head list;
+	struct gfs2_jdesc *jd;
+
+	spin_lock(&sdp->sd_jindex_spin);
+	list_add(&list, &sdp->sd_jindex_list);
+	list_del_init(&sdp->sd_jindex_list);
+	sdp->sd_journals = 0;
+	spin_unlock(&sdp->sd_jindex_spin);
+
+	sdp->sd_jdesc = NULL;
+	while (!list_empty(&list)) {
+		jd = list_first_entry(&list, struct gfs2_jdesc, jd_list);
+		gfs2_free_journal_extents(jd);
+		list_del(&jd->jd_list);
+		iput(jd->jd_inode);
+		jd->jd_inode = NULL;
+		kfree(jd);
+	}
+}
+
+static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
+{
+	struct gfs2_jdesc *jd;
+
+	list_for_each_entry(jd, head, jd_list) {
+		if (jd->jd_jid == jid)
+			return jd;
+	}
+	return NULL;
+}
+
+struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
+{
+	struct gfs2_jdesc *jd;
+
+	spin_lock(&sdp->sd_jindex_spin);
+	jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
+	spin_unlock(&sdp->sd_jindex_spin);
+
+	return jd;
+}
+
+int gfs2_jdesc_check(struct gfs2_jdesc *jd)
+{
+	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
+	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
+	u64 size = i_size_read(jd->jd_inode);
+
+	if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, BIT(30)))
+		return -EIO;
+
+	jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
+
+	if (gfs2_write_alloc_required(ip, 0, size)) {
+		gfs2_consist_inode(ip);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
+ * @sdp: the filesystem
+ *
+ * Returns: errno
+ */
+
+int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
+{
+	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
+	struct gfs2_glock *j_gl = ip->i_gl;
+	struct gfs2_log_header_host head;
+	int error;
+
+	j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
+	if (gfs2_withdrawn(sdp))
+		return -EIO;
+
+	error = gfs2_find_jhead(sdp->sd_jdesc, &head, false);
+	if (error) {
+		gfs2_consist(sdp);
+		return error;
+	}
+
+	if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
+		gfs2_consist(sdp);
+		return -EIO;
+	}
+
+	/*  Initialize some head of the log stuff  */
+	sdp->sd_log_sequence = head.lh_sequence + 1;
+	gfs2_log_pointers_init(sdp, head.lh_blkno);
+
+	error = gfs2_quota_init(sdp);
+	if (!error && gfs2_withdrawn(sdp))
+		error = -EIO;
+	if (!error)
+		set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
+	return error;
+}
+
+void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
+{
+	const struct gfs2_statfs_change *str = buf;
+
+	sc->sc_total = be64_to_cpu(str->sc_total);
+	sc->sc_free = be64_to_cpu(str->sc_free);
+	sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
+}
+
+void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
+{
+	struct gfs2_statfs_change *str = buf;
+
+	str->sc_total = cpu_to_be64(sc->sc_total);
+	str->sc_free = cpu_to_be64(sc->sc_free);
+	str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
+}
+
+int gfs2_statfs_init(struct gfs2_sbd *sdp)
+{
+	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+	struct buffer_head *m_bh;
+	struct gfs2_holder gh;
+	int error;
+
+	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
+				   &gh);
+	if (error)
+		return error;
+
+	error = gfs2_meta_inode_buffer(m_ip, &m_bh);
+	if (error)
+		goto out;
+
+	if (sdp->sd_args.ar_spectator) {
+		spin_lock(&sdp->sd_statfs_spin);
+		gfs2_statfs_change_in(m_sc, m_bh->b_data +
+				      sizeof(struct gfs2_dinode));
+		spin_unlock(&sdp->sd_statfs_spin);
+	} else {
+		spin_lock(&sdp->sd_statfs_spin);
+		gfs2_statfs_change_in(m_sc, m_bh->b_data +
+				      sizeof(struct gfs2_dinode));
+		gfs2_statfs_change_in(l_sc, sdp->sd_sc_bh->b_data +
+				      sizeof(struct gfs2_dinode));
+		spin_unlock(&sdp->sd_statfs_spin);
+
+	}
+
+	brelse(m_bh);
+out:
+	gfs2_glock_dq_uninit(&gh);
+	return 0;
+}
+
+void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
+			s64 dinodes)
+{
+	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	s64 x, y;
+	int need_sync = 0;
+
+	gfs2_trans_add_meta(l_ip->i_gl, sdp->sd_sc_bh);
+
+	spin_lock(&sdp->sd_statfs_spin);
+	l_sc->sc_total += total;
+	l_sc->sc_free += free;
+	l_sc->sc_dinodes += dinodes;
+	gfs2_statfs_change_out(l_sc, sdp->sd_sc_bh->b_data +
+			       sizeof(struct gfs2_dinode));
+	if (sdp->sd_args.ar_statfs_percent) {
+		x = 100 * l_sc->sc_free;
+		y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
+		if (x >= y || x <= -y)
+			need_sync = 1;
+	}
+	spin_unlock(&sdp->sd_statfs_spin);
+
+	if (need_sync)
+		gfs2_wake_up_statfs(sdp);
+}
+
+void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh)
+{
+	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
+	struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+
+	gfs2_trans_add_meta(l_ip->i_gl, sdp->sd_sc_bh);
+	gfs2_trans_add_meta(m_ip->i_gl, m_bh);
+
+	spin_lock(&sdp->sd_statfs_spin);
+	m_sc->sc_total += l_sc->sc_total;
+	m_sc->sc_free += l_sc->sc_free;
+	m_sc->sc_dinodes += l_sc->sc_dinodes;
+	memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
+	memset(sdp->sd_sc_bh->b_data + sizeof(struct gfs2_dinode),
+	       0, sizeof(struct gfs2_statfs_change));
+	gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
+	spin_unlock(&sdp->sd_statfs_spin);
+}
+
+int gfs2_statfs_sync(struct super_block *sb, int type)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+	struct gfs2_holder gh;
+	struct buffer_head *m_bh;
+	int error;
+
+	error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
+				   &gh);
+	if (error)
+		goto out;
+
+	error = gfs2_meta_inode_buffer(m_ip, &m_bh);
+	if (error)
+		goto out_unlock;
+
+	spin_lock(&sdp->sd_statfs_spin);
+	gfs2_statfs_change_in(m_sc, m_bh->b_data +
+			      sizeof(struct gfs2_dinode));
+	if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
+		spin_unlock(&sdp->sd_statfs_spin);
+		goto out_bh;
+	}
+	spin_unlock(&sdp->sd_statfs_spin);
+
+	error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
+	if (error)
+		goto out_bh;
+
+	update_statfs(sdp, m_bh);
+	sdp->sd_statfs_force_sync = 0;
+
+	gfs2_trans_end(sdp);
+
+out_bh:
+	brelse(m_bh);
+out_unlock:
+	gfs2_glock_dq_uninit(&gh);
+out:
+	return error;
+}
+
+struct lfcc {
+	struct list_head list;
+	struct gfs2_holder gh;
+};
+
+/**
+ * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
+ *                            journals are clean
+ * @sdp: the file system
+ *
+ * Returns: errno
+ */
+
+static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp)
+{
+	struct gfs2_inode *ip;
+	struct gfs2_jdesc *jd;
+	struct lfcc *lfcc;
+	LIST_HEAD(list);
+	struct gfs2_log_header_host lh;
+	int error, error2;
+
+	/*
+	 * Grab all the journal glocks in SH mode.  We are *probably* doing
+	 * that to prevent recovery.
+	 */
+
+	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+		lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
+		if (!lfcc) {
+			error = -ENOMEM;
+			goto out;
+		}
+		ip = GFS2_I(jd->jd_inode);
+		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
+		if (error) {
+			kfree(lfcc);
+			goto out;
+		}
+		list_add(&lfcc->list, &list);
+	}
+
+	gfs2_freeze_unlock(&sdp->sd_freeze_gh);
+
+	error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE,
+				   LM_FLAG_NOEXP | GL_NOPID,
+				   &sdp->sd_freeze_gh);
+	if (error)
+		goto relock_shared;
+
+	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+		error = gfs2_jdesc_check(jd);
+		if (error)
+			break;
+		error = gfs2_find_jhead(jd, &lh, false);
+		if (error)
+			break;
+		if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
+			error = -EBUSY;
+			break;
+		}
+	}
+
+	if (!error)
+		goto out;  /* success */
+
+	gfs2_freeze_unlock(&sdp->sd_freeze_gh);
+
+relock_shared:
+	error2 = gfs2_freeze_lock_shared(sdp);
+	gfs2_assert_withdraw(sdp, !error2);
+
+out:
+	while (!list_empty(&list)) {
+		lfcc = list_first_entry(&list, struct lfcc, list);
+		list_del(&lfcc->list);
+		gfs2_glock_dq_uninit(&lfcc->gh);
+		kfree(lfcc);
+	}
+	return error;
+}
+
+void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
+{
+	const struct inode *inode = &ip->i_inode;
+	struct gfs2_dinode *str = buf;
+
+	str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
+	str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
+	str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
+	str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
+	str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
+	str->di_mode = cpu_to_be32(inode->i_mode);
+	str->di_uid = cpu_to_be32(i_uid_read(inode));
+	str->di_gid = cpu_to_be32(i_gid_read(inode));
+	str->di_nlink = cpu_to_be32(inode->i_nlink);
+	str->di_size = cpu_to_be64(i_size_read(inode));
+	str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(inode));
+	str->di_atime = cpu_to_be64(inode->i_atime.tv_sec);
+	str->di_mtime = cpu_to_be64(inode->i_mtime.tv_sec);
+	str->di_ctime = cpu_to_be64(inode_get_ctime(inode).tv_sec);
+
+	str->di_goal_meta = cpu_to_be64(ip->i_goal);
+	str->di_goal_data = cpu_to_be64(ip->i_goal);
+	str->di_generation = cpu_to_be64(ip->i_generation);
+
+	str->di_flags = cpu_to_be32(ip->i_diskflags);
+	str->di_height = cpu_to_be16(ip->i_height);
+	str->di_payload_format = cpu_to_be32(S_ISDIR(inode->i_mode) &&
+					     !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
+					     GFS2_FORMAT_DE : 0);
+	str->di_depth = cpu_to_be16(ip->i_depth);
+	str->di_entries = cpu_to_be32(ip->i_entries);
+
+	str->di_eattr = cpu_to_be64(ip->i_eattr);
+	str->di_atime_nsec = cpu_to_be32(inode->i_atime.tv_nsec);
+	str->di_mtime_nsec = cpu_to_be32(inode->i_mtime.tv_nsec);
+	str->di_ctime_nsec = cpu_to_be32(inode_get_ctime(inode).tv_nsec);
+}
+
+/**
+ * gfs2_write_inode - Make sure the inode is stable on the disk
+ * @inode: The inode
+ * @wbc: The writeback control structure
+ *
+ * Returns: errno
+ */
+
+static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
+	struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
+	struct backing_dev_info *bdi = inode_to_bdi(metamapping->host);
+	int ret = 0;
+	bool flush_all = (wbc->sync_mode == WB_SYNC_ALL || gfs2_is_jdata(ip));
+
+	if (flush_all)
+		gfs2_log_flush(GFS2_SB(inode), ip->i_gl,
+			       GFS2_LOG_HEAD_FLUSH_NORMAL |
+			       GFS2_LFC_WRITE_INODE);
+	if (bdi->wb.dirty_exceeded)
+		gfs2_ail1_flush(sdp, wbc);
+	else
+		filemap_fdatawrite(metamapping);
+	if (flush_all)
+		ret = filemap_fdatawait(metamapping);
+	if (ret)
+		mark_inode_dirty_sync(inode);
+	else {
+		spin_lock(&inode->i_lock);
+		if (!(inode->i_flags & I_DIRTY))
+			gfs2_ordered_del_inode(ip);
+		spin_unlock(&inode->i_lock);
+	}
+	return ret;
+}
+
+/**
+ * gfs2_dirty_inode - check for atime updates
+ * @inode: The inode in question
+ * @flags: The type of dirty
+ *
+ * Unfortunately it can be called under any combination of inode
+ * glock and freeze glock, so we have to check carefully.
+ *
+ * At the moment this deals only with atime - it should be possible
+ * to expand that role in future, once a review of the locking has
+ * been carried out.
+ */
+
+static void gfs2_dirty_inode(struct inode *inode, int flags)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
+	struct buffer_head *bh;
+	struct gfs2_holder gh;
+	int need_unlock = 0;
+	int need_endtrans = 0;
+	int ret;
+
+	if (unlikely(!ip->i_gl)) {
+		/* This can only happen during incomplete inode creation. */
+		BUG_ON(!test_bit(GIF_ALLOC_FAILED, &ip->i_flags));
+		return;
+	}
+
+	if (unlikely(gfs2_withdrawn(sdp)))
+		return;
+	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
+		ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+		if (ret) {
+			fs_err(sdp, "dirty_inode: glock %d\n", ret);
+			gfs2_dump_glock(NULL, ip->i_gl, true);
+			return;
+		}
+		need_unlock = 1;
+	} else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE))
+		return;
+
+	if (current->journal_info == NULL) {
+		ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
+		if (ret) {
+			fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
+			goto out;
+		}
+		need_endtrans = 1;
+	}
+
+	ret = gfs2_meta_inode_buffer(ip, &bh);
+	if (ret == 0) {
+		gfs2_trans_add_meta(ip->i_gl, bh);
+		gfs2_dinode_out(ip, bh->b_data);
+		brelse(bh);
+	}
+
+	if (need_endtrans)
+		gfs2_trans_end(sdp);
+out:
+	if (need_unlock)
+		gfs2_glock_dq_uninit(&gh);
+}
+
+/**
+ * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
+ * @sdp: the filesystem
+ *
+ * Returns: errno
+ */
+
+void gfs2_make_fs_ro(struct gfs2_sbd *sdp)
+{
+	int log_write_allowed = test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
+
+	if (!test_bit(SDF_KILL, &sdp->sd_flags))
+		gfs2_flush_delete_work(sdp);
+
+	gfs2_destroy_threads(sdp);
+
+	if (log_write_allowed) {
+		gfs2_quota_sync(sdp->sd_vfs, 0);
+		gfs2_statfs_sync(sdp->sd_vfs, 0);
+
+		/* We do two log flushes here. The first one commits dirty inodes
+		 * and rgrps to the journal, but queues up revokes to the ail list.
+		 * The second flush writes out and removes the revokes.
+		 *
+		 * The first must be done before the FLUSH_SHUTDOWN code
+		 * clears the LIVE flag, otherwise it will not be able to start
+		 * a transaction to write its revokes, and the error will cause
+		 * a withdraw of the file system. */
+		gfs2_log_flush(sdp, NULL, GFS2_LFC_MAKE_FS_RO);
+		gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
+			       GFS2_LFC_MAKE_FS_RO);
+		wait_event_timeout(sdp->sd_log_waitq,
+				   gfs2_log_is_empty(sdp),
+				   HZ * 5);
+		gfs2_assert_warn(sdp, gfs2_log_is_empty(sdp));
+	}
+	gfs2_quota_cleanup(sdp);
+}
+
+/**
+ * gfs2_put_super - Unmount the filesystem
+ * @sb: The VFS superblock
+ *
+ */
+
+static void gfs2_put_super(struct super_block *sb)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_jdesc *jd;
+
+	/* No more recovery requests */
+	set_bit(SDF_NORECOVERY, &sdp->sd_flags);
+	smp_mb();
+
+	/* Wait on outstanding recovery */
+restart:
+	spin_lock(&sdp->sd_jindex_spin);
+	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+		if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
+			continue;
+		spin_unlock(&sdp->sd_jindex_spin);
+		wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
+			    TASK_UNINTERRUPTIBLE);
+		goto restart;
+	}
+	spin_unlock(&sdp->sd_jindex_spin);
+
+	if (!sb_rdonly(sb))
+		gfs2_make_fs_ro(sdp);
+	else {
+		if (gfs2_withdrawn(sdp))
+			gfs2_destroy_threads(sdp);
+
+		gfs2_quota_cleanup(sdp);
+	}
+
+	WARN_ON(gfs2_withdrawing(sdp));
+
+	/*  At this point, we're through modifying the disk  */
+
+	/*  Release stuff  */
+
+	gfs2_freeze_unlock(&sdp->sd_freeze_gh);
+
+	iput(sdp->sd_jindex);
+	iput(sdp->sd_statfs_inode);
+	iput(sdp->sd_rindex);
+	iput(sdp->sd_quota_inode);
+
+	gfs2_glock_put(sdp->sd_rename_gl);
+	gfs2_glock_put(sdp->sd_freeze_gl);
+
+	if (!sdp->sd_args.ar_spectator) {
+		if (gfs2_holder_initialized(&sdp->sd_journal_gh))
+			gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
+		if (gfs2_holder_initialized(&sdp->sd_jinode_gh))
+			gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
+		brelse(sdp->sd_sc_bh);
+		gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
+		gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
+		free_local_statfs_inodes(sdp);
+		iput(sdp->sd_qc_inode);
+	}
+
+	gfs2_glock_dq_uninit(&sdp->sd_live_gh);
+	gfs2_clear_rgrpd(sdp);
+	gfs2_jindex_free(sdp);
+	/*  Take apart glock structures and buffer lists  */
+	gfs2_gl_hash_clear(sdp);
+	truncate_inode_pages_final(&sdp->sd_aspace);
+	gfs2_delete_debugfs_file(sdp);
+	/*  Unmount the locking protocol  */
+	gfs2_lm_unmount(sdp);
+
+	/*  At this point, we're through participating in the lockspace  */
+	gfs2_sys_fs_del(sdp);
+	free_sbd(sdp);
+}
+
+/**
+ * gfs2_sync_fs - sync the filesystem
+ * @sb: the superblock
+ * @wait: true to wait for completion
+ *
+ * Flushes the log to disk.
+ */
+
+static int gfs2_sync_fs(struct super_block *sb, int wait)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+
+	gfs2_quota_sync(sb, -1);
+	if (wait)
+		gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
+			       GFS2_LFC_SYNC_FS);
+	return sdp->sd_log_error;
+}
+
+static int gfs2_freeze_locally(struct gfs2_sbd *sdp)
+{
+	struct super_block *sb = sdp->sd_vfs;
+	int error;
+
+	error = freeze_super(sb, FREEZE_HOLDER_USERSPACE);
+	if (error)
+		return error;
+
+	if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
+		gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_FREEZE |
+			       GFS2_LFC_FREEZE_GO_SYNC);
+		if (gfs2_withdrawn(sdp)) {
+			error = thaw_super(sb, FREEZE_HOLDER_USERSPACE);
+			if (error)
+				return error;
+			return -EIO;
+		}
+	}
+	return 0;
+}
+
+static int gfs2_do_thaw(struct gfs2_sbd *sdp)
+{
+	struct super_block *sb = sdp->sd_vfs;
+	int error;
+
+	error = gfs2_freeze_lock_shared(sdp);
+	if (error)
+		goto fail;
+	error = thaw_super(sb, FREEZE_HOLDER_USERSPACE);
+	if (!error)
+		return 0;
+
+fail:
+	fs_info(sdp, "GFS2: couldn't thaw filesystem: %d\n", error);
+	gfs2_assert_withdraw(sdp, 0);
+	return error;
+}
+
+void gfs2_freeze_func(struct work_struct *work)
+{
+	struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_freeze_work);
+	struct super_block *sb = sdp->sd_vfs;
+	int error;
+
+	mutex_lock(&sdp->sd_freeze_mutex);
+	error = -EBUSY;
+	if (test_bit(SDF_FROZEN, &sdp->sd_flags))
+		goto freeze_failed;
+
+	error = gfs2_freeze_locally(sdp);
+	if (error)
+		goto freeze_failed;
+
+	gfs2_freeze_unlock(&sdp->sd_freeze_gh);
+	set_bit(SDF_FROZEN, &sdp->sd_flags);
+
+	error = gfs2_do_thaw(sdp);
+	if (error)
+		goto out;
+
+	clear_bit(SDF_FROZEN, &sdp->sd_flags);
+	goto out;
+
+freeze_failed:
+	fs_info(sdp, "GFS2: couldn't freeze filesystem: %d\n", error);
+
+out:
+	mutex_unlock(&sdp->sd_freeze_mutex);
+	deactivate_super(sb);
+}
+
+/**
+ * gfs2_freeze_super - prevent further writes to the filesystem
+ * @sb: the VFS structure for the filesystem
+ *
+ */
+
+static int gfs2_freeze_super(struct super_block *sb, enum freeze_holder who)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	int error;
+
+	if (!mutex_trylock(&sdp->sd_freeze_mutex))
+		return -EBUSY;
+	error = -EBUSY;
+	if (test_bit(SDF_FROZEN, &sdp->sd_flags))
+		goto out;
+
+	for (;;) {
+		error = gfs2_freeze_locally(sdp);
+		if (error) {
+			fs_info(sdp, "GFS2: couldn't freeze filesystem: %d\n",
+				error);
+			goto out;
+		}
+
+		error = gfs2_lock_fs_check_clean(sdp);
+		if (!error)
+			break;  /* success */
+
+		error = gfs2_do_thaw(sdp);
+		if (error)
+			goto out;
+
+		if (error == -EBUSY)
+			fs_err(sdp, "waiting for recovery before freeze\n");
+		else if (error == -EIO) {
+			fs_err(sdp, "Fatal IO error: cannot freeze gfs2 due "
+			       "to recovery error.\n");
+			goto out;
+		} else {
+			fs_err(sdp, "error freezing FS: %d\n", error);
+		}
+		fs_err(sdp, "retrying...\n");
+		msleep(1000);
+	}
+
+out:
+	if (!error) {
+		set_bit(SDF_FREEZE_INITIATOR, &sdp->sd_flags);
+		set_bit(SDF_FROZEN, &sdp->sd_flags);
+	}
+	mutex_unlock(&sdp->sd_freeze_mutex);
+	return error;
+}
+
+/**
+ * gfs2_thaw_super - reallow writes to the filesystem
+ * @sb: the VFS structure for the filesystem
+ *
+ */
+
+static int gfs2_thaw_super(struct super_block *sb, enum freeze_holder who)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	int error;
+
+	if (!mutex_trylock(&sdp->sd_freeze_mutex))
+		return -EBUSY;
+	error = -EINVAL;
+	if (!test_bit(SDF_FREEZE_INITIATOR, &sdp->sd_flags))
+		goto out;
+
+	gfs2_freeze_unlock(&sdp->sd_freeze_gh);
+
+	error = gfs2_do_thaw(sdp);
+
+	if (!error) {
+		clear_bit(SDF_FREEZE_INITIATOR, &sdp->sd_flags);
+		clear_bit(SDF_FROZEN, &sdp->sd_flags);
+	}
+out:
+	mutex_unlock(&sdp->sd_freeze_mutex);
+	return error;
+}
+
+void gfs2_thaw_freeze_initiator(struct super_block *sb)
+{
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+
+	mutex_lock(&sdp->sd_freeze_mutex);
+	if (!test_bit(SDF_FREEZE_INITIATOR, &sdp->sd_flags))
+		goto out;
+
+	gfs2_freeze_unlock(&sdp->sd_freeze_gh);
+
+out:
+	mutex_unlock(&sdp->sd_freeze_mutex);
+}
+
+/**
+ * statfs_slow_fill - fill in the sg for a given RG
+ * @rgd: the RG
+ * @sc: the sc structure
+ *
+ * Returns: 0 on success, -ESTALE if the LVB is invalid
+ */
+
+static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
+			    struct gfs2_statfs_change_host *sc)
+{
+	gfs2_rgrp_verify(rgd);
+	sc->sc_total += rgd->rd_data;
+	sc->sc_free += rgd->rd_free;
+	sc->sc_dinodes += rgd->rd_dinodes;
+	return 0;
+}
+
+/**
+ * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
+ * @sdp: the filesystem
+ * @sc: the sc info that will be returned
+ *
+ * Any error (other than a signal) will cause this routine to fall back
+ * to the synchronous version.
+ *
+ * FIXME: This really shouldn't busy wait like this.
+ *
+ * Returns: errno
+ */
+
+static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
+{
+	struct gfs2_rgrpd *rgd_next;
+	struct gfs2_holder *gha, *gh;
+	unsigned int slots = 64;
+	unsigned int x;
+	int done;
+	int error = 0, err;
+
+	memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
+	gha = kmalloc_array(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
+	if (!gha)
+		return -ENOMEM;
+	for (x = 0; x < slots; x++)
+		gfs2_holder_mark_uninitialized(gha + x);
+
+	rgd_next = gfs2_rgrpd_get_first(sdp);
+
+	for (;;) {
+		done = 1;
+
+		for (x = 0; x < slots; x++) {
+			gh = gha + x;
+
+			if (gfs2_holder_initialized(gh) && gfs2_glock_poll(gh)) {
+				err = gfs2_glock_wait(gh);
+				if (err) {
+					gfs2_holder_uninit(gh);
+					error = err;
+				} else {
+					if (!error) {
+						struct gfs2_rgrpd *rgd =
+							gfs2_glock2rgrp(gh->gh_gl);
+
+						error = statfs_slow_fill(rgd, sc);
+					}
+					gfs2_glock_dq_uninit(gh);
+				}
+			}
+
+			if (gfs2_holder_initialized(gh))
+				done = 0;
+			else if (rgd_next && !error) {
+				error = gfs2_glock_nq_init(rgd_next->rd_gl,
+							   LM_ST_SHARED,
+							   GL_ASYNC,
+							   gh);
+				rgd_next = gfs2_rgrpd_get_next(rgd_next);
+				done = 0;
+			}
+
+			if (signal_pending(current))
+				error = -ERESTARTSYS;
+		}
+
+		if (done)
+			break;
+
+		yield();
+	}
+
+	kfree(gha);
+	return error;
+}
+
+/**
+ * gfs2_statfs_i - Do a statfs
+ * @sdp: the filesystem
+ * @sc: the sc structure
+ *
+ * Returns: errno
+ */
+
+static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
+{
+	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
+	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
+
+	spin_lock(&sdp->sd_statfs_spin);
+
+	*sc = *m_sc;
+	sc->sc_total += l_sc->sc_total;
+	sc->sc_free += l_sc->sc_free;
+	sc->sc_dinodes += l_sc->sc_dinodes;
+
+	spin_unlock(&sdp->sd_statfs_spin);
+
+	if (sc->sc_free < 0)
+		sc->sc_free = 0;
+	if (sc->sc_free > sc->sc_total)
+		sc->sc_free = sc->sc_total;
+	if (sc->sc_dinodes < 0)
+		sc->sc_dinodes = 0;
+
+	return 0;
+}
+
+/**
+ * gfs2_statfs - Gather and return stats about the filesystem
+ * @dentry: The name of the link
+ * @buf: The buffer
+ *
+ * Returns: 0 on success or error code
+ */
+
+static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct super_block *sb = dentry->d_sb;
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_statfs_change_host sc;
+	int error;
+
+	error = gfs2_rindex_update(sdp);
+	if (error)
+		return error;
+
+	if (gfs2_tune_get(sdp, gt_statfs_slow))
+		error = gfs2_statfs_slow(sdp, &sc);
+	else
+		error = gfs2_statfs_i(sdp, &sc);
+
+	if (error)
+		return error;
+
+	buf->f_type = GFS2_MAGIC;
+	buf->f_bsize = sdp->sd_sb.sb_bsize;
+	buf->f_blocks = sc.sc_total;
+	buf->f_bfree = sc.sc_free;
+	buf->f_bavail = sc.sc_free;
+	buf->f_files = sc.sc_dinodes + sc.sc_free;
+	buf->f_ffree = sc.sc_free;
+	buf->f_namelen = GFS2_FNAMESIZE;
+
+	return 0;
+}
+
+/**
+ * gfs2_drop_inode - Drop an inode (test for remote unlink)
+ * @inode: The inode to drop
+ *
+ * If we've received a callback on an iopen lock then it's because a
+ * remote node tried to deallocate the inode but failed due to this node
+ * still having the inode open. Here we mark the link count zero
+ * since we know that it must have reached zero if the GLF_DEMOTE flag
+ * is set on the iopen glock. If we didn't do a disk read since the
+ * remote node removed the final link then we might otherwise miss
+ * this event. This check ensures that this node will deallocate the
+ * inode's blocks, or alternatively pass the baton on to another
+ * node for later deallocation.
+ */
+
+static int gfs2_drop_inode(struct inode *inode)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
+
+	if (inode->i_nlink &&
+	    gfs2_holder_initialized(&ip->i_iopen_gh)) {
+		struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
+		if (test_bit(GLF_DEMOTE, &gl->gl_flags))
+			clear_nlink(inode);
+	}
+
+	/*
+	 * When under memory pressure when an inode's link count has dropped to
+	 * zero, defer deleting the inode to the delete workqueue.  This avoids
+	 * calling into DLM under memory pressure, which can deadlock.
+	 */
+	if (!inode->i_nlink &&
+	    unlikely(current->flags & PF_MEMALLOC) &&
+	    gfs2_holder_initialized(&ip->i_iopen_gh)) {
+		struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
+
+		gfs2_glock_hold(gl);
+		if (!gfs2_queue_try_to_evict(gl))
+			gfs2_glock_queue_put(gl);
+		return 0;
+	}
+
+	/*
+	 * No longer cache inodes when trying to evict them all.
+	 */
+	if (test_bit(SDF_EVICTING, &sdp->sd_flags))
+		return 1;
+
+	return generic_drop_inode(inode);
+}
+
+static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
+{
+	do {
+		if (d1 == d2)
+			return 1;
+		d1 = d1->d_parent;
+	} while (!IS_ROOT(d1));
+	return 0;
+}
+
+/**
+ * gfs2_show_options - Show mount options for /proc/mounts
+ * @s: seq_file structure
+ * @root: root of this (sub)tree
+ *
+ * Returns: 0 on success or error code
+ */
+
+static int gfs2_show_options(struct seq_file *s, struct dentry *root)
+{
+	struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
+	struct gfs2_args *args = &sdp->sd_args;
+	unsigned int logd_secs, statfs_slow, statfs_quantum, quota_quantum;
+
+	spin_lock(&sdp->sd_tune.gt_spin);
+	logd_secs = sdp->sd_tune.gt_logd_secs;
+	quota_quantum = sdp->sd_tune.gt_quota_quantum;
+	statfs_quantum = sdp->sd_tune.gt_statfs_quantum;
+	statfs_slow = sdp->sd_tune.gt_statfs_slow;
+	spin_unlock(&sdp->sd_tune.gt_spin);
+
+	if (is_ancestor(root, sdp->sd_master_dir))
+		seq_puts(s, ",meta");
+	if (args->ar_lockproto[0])
+		seq_show_option(s, "lockproto", args->ar_lockproto);
+	if (args->ar_locktable[0])
+		seq_show_option(s, "locktable", args->ar_locktable);
+	if (args->ar_hostdata[0])
+		seq_show_option(s, "hostdata", args->ar_hostdata);
+	if (args->ar_spectator)
+		seq_puts(s, ",spectator");
+	if (args->ar_localflocks)
+		seq_puts(s, ",localflocks");
+	if (args->ar_debug)
+		seq_puts(s, ",debug");
+	if (args->ar_posix_acl)
+		seq_puts(s, ",acl");
+	if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
+		char *state;
+		switch (args->ar_quota) {
+		case GFS2_QUOTA_OFF:
+			state = "off";
+			break;
+		case GFS2_QUOTA_ACCOUNT:
+			state = "account";
+			break;
+		case GFS2_QUOTA_ON:
+			state = "on";
+			break;
+		case GFS2_QUOTA_QUIET:
+			state = "quiet";
+			break;
+		default:
+			state = "unknown";
+			break;
+		}
+		seq_printf(s, ",quota=%s", state);
+	}
+	if (args->ar_suiddir)
+		seq_puts(s, ",suiddir");
+	if (args->ar_data != GFS2_DATA_DEFAULT) {
+		char *state;
+		switch (args->ar_data) {
+		case GFS2_DATA_WRITEBACK:
+			state = "writeback";
+			break;
+		case GFS2_DATA_ORDERED:
+			state = "ordered";
+			break;
+		default:
+			state = "unknown";
+			break;
+		}
+		seq_printf(s, ",data=%s", state);
+	}
+	if (args->ar_discard)
+		seq_puts(s, ",discard");
+	if (logd_secs != 30)
+		seq_printf(s, ",commit=%d", logd_secs);
+	if (statfs_quantum != 30)
+		seq_printf(s, ",statfs_quantum=%d", statfs_quantum);
+	else if (statfs_slow)
+		seq_puts(s, ",statfs_quantum=0");
+	if (quota_quantum != 60)
+		seq_printf(s, ",quota_quantum=%d", quota_quantum);
+	if (args->ar_statfs_percent)
+		seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
+	if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
+		const char *state;
+
+		switch (args->ar_errors) {
+		case GFS2_ERRORS_WITHDRAW:
+			state = "withdraw";
+			break;
+		case GFS2_ERRORS_PANIC:
+			state = "panic";
+			break;
+		default:
+			state = "unknown";
+			break;
+		}
+		seq_printf(s, ",errors=%s", state);
+	}
+	if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
+		seq_puts(s, ",nobarrier");
+	if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
+		seq_puts(s, ",demote_interface_used");
+	if (args->ar_rgrplvb)
+		seq_puts(s, ",rgrplvb");
+	if (args->ar_loccookie)
+		seq_puts(s, ",loccookie");
+	return 0;
+}
+
+static void gfs2_final_release_pages(struct gfs2_inode *ip)
+{
+	struct inode *inode = &ip->i_inode;
+	struct gfs2_glock *gl = ip->i_gl;
+
+	if (unlikely(!gl)) {
+		/* This can only happen during incomplete inode creation. */
+		BUG_ON(!test_bit(GIF_ALLOC_FAILED, &ip->i_flags));
+		return;
+	}
+
+	truncate_inode_pages(gfs2_glock2aspace(gl), 0);
+	truncate_inode_pages(&inode->i_data, 0);
+
+	if (atomic_read(&gl->gl_revokes) == 0) {
+		clear_bit(GLF_LFLUSH, &gl->gl_flags);
+		clear_bit(GLF_DIRTY, &gl->gl_flags);
+	}
+}
+
+static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
+{
+	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+	struct gfs2_rgrpd *rgd;
+	struct gfs2_holder gh;
+	int error;
+
+	if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
+		gfs2_consist_inode(ip);
+		return -EIO;
+	}
+
+	gfs2_rindex_update(sdp);
+
+	error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
+	if (error)
+		return error;
+
+	rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
+	if (!rgd) {
+		gfs2_consist_inode(ip);
+		error = -EIO;
+		goto out_qs;
+	}
+
+	error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE,
+				   LM_FLAG_NODE_SCOPE, &gh);
+	if (error)
+		goto out_qs;
+
+	error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
+				 sdp->sd_jdesc->jd_blocks);
+	if (error)
+		goto out_rg_gunlock;
+
+	gfs2_free_di(rgd, ip);
+
+	gfs2_final_release_pages(ip);
+
+	gfs2_trans_end(sdp);
+
+out_rg_gunlock:
+	gfs2_glock_dq_uninit(&gh);
+out_qs:
+	gfs2_quota_unhold(ip);
+	return error;
+}
+
+/**
+ * gfs2_glock_put_eventually
+ * @gl:	The glock to put
+ *
+ * When under memory pressure, trigger a deferred glock put to make sure we
+ * won't call into DLM and deadlock.  Otherwise, put the glock directly.
+ */
+
+static void gfs2_glock_put_eventually(struct gfs2_glock *gl)
+{
+	if (current->flags & PF_MEMALLOC)
+		gfs2_glock_queue_put(gl);
+	else
+		gfs2_glock_put(gl);
+}
+
+static bool gfs2_upgrade_iopen_glock(struct inode *inode)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_sbd *sdp = GFS2_SB(inode);
+	struct gfs2_holder *gh = &ip->i_iopen_gh;
+	long timeout = 5 * HZ;
+	int error;
+
+	gh->gh_flags |= GL_NOCACHE;
+	gfs2_glock_dq_wait(gh);
+
+	/*
+	 * If there are no other lock holders, we will immediately get
+	 * exclusive access to the iopen glock here.
+	 *
+	 * Otherwise, the other nodes holding the lock will be notified about
+	 * our locking request.  If they do not have the inode open, they are
+	 * expected to evict the cached inode and release the lock, allowing us
+	 * to proceed.
+	 *
+	 * Otherwise, if they cannot evict the inode, they are expected to poke
+	 * the inode glock (note: not the iopen glock).  We will notice that
+	 * and stop waiting for the iopen glock immediately.  The other node(s)
+	 * are then expected to take care of deleting the inode when they no
+	 * longer use it.
+	 *
+	 * As a last resort, if another node keeps holding the iopen glock
+	 * without showing any activity on the inode glock, we will eventually
+	 * time out and fail the iopen glock upgrade.
+	 *
+	 * Note that we're passing the LM_FLAG_TRY_1CB flag to the first
+	 * locking request as an optimization to notify lock holders as soon as
+	 * possible.  Without that flag, they'd be notified implicitly by the
+	 * second locking request.
+	 */
+
+	gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, gh);
+	error = gfs2_glock_nq(gh);
+	if (error != GLR_TRYFAILED)
+		return !error;
+
+	gfs2_holder_reinit(LM_ST_EXCLUSIVE, GL_ASYNC | GL_NOCACHE, gh);
+	error = gfs2_glock_nq(gh);
+	if (error)
+		return false;
+
+	timeout = wait_event_interruptible_timeout(sdp->sd_async_glock_wait,
+		!test_bit(HIF_WAIT, &gh->gh_iflags) ||
+		test_bit(GLF_DEMOTE, &ip->i_gl->gl_flags),
+		timeout);
+	if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) {
+		gfs2_glock_dq(gh);
+		return false;
+	}
+	return gfs2_glock_holder_ready(gh) == 0;
+}
+
+/**
+ * evict_should_delete - determine whether the inode is eligible for deletion
+ * @inode: The inode to evict
+ * @gh: The glock holder structure
+ *
+ * This function determines whether the evicted inode is eligible to be deleted
+ * and locks the inode glock.
+ *
+ * Returns: the fate of the dinode
+ */
+static enum dinode_demise evict_should_delete(struct inode *inode,
+					      struct gfs2_holder *gh)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct super_block *sb = inode->i_sb;
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	int ret;
+
+	if (unlikely(test_bit(GIF_ALLOC_FAILED, &ip->i_flags)))
+		goto should_delete;
+
+	if (test_bit(GIF_DEFERRED_DELETE, &ip->i_flags))
+		return SHOULD_DEFER_EVICTION;
+
+	/* Deletes should never happen under memory pressure anymore.  */
+	if (WARN_ON_ONCE(current->flags & PF_MEMALLOC))
+		return SHOULD_DEFER_EVICTION;
+
+	/* Must not read inode block until block type has been verified */
+	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, gh);
+	if (unlikely(ret)) {
+		glock_clear_object(ip->i_iopen_gh.gh_gl, ip);
+		ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
+		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
+		return SHOULD_DEFER_EVICTION;
+	}
+
+	if (gfs2_inode_already_deleted(ip->i_gl, ip->i_no_formal_ino))
+		return SHOULD_NOT_DELETE_DINODE;
+	ret = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
+	if (ret)
+		return SHOULD_NOT_DELETE_DINODE;
+
+	ret = gfs2_instantiate(gh);
+	if (ret)
+		return SHOULD_NOT_DELETE_DINODE;
+
+	/*
+	 * The inode may have been recreated in the meantime.
+	 */
+	if (inode->i_nlink)
+		return SHOULD_NOT_DELETE_DINODE;
+
+should_delete:
+	if (gfs2_holder_initialized(&ip->i_iopen_gh) &&
+	    test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
+		if (!gfs2_upgrade_iopen_glock(inode)) {
+			gfs2_holder_uninit(&ip->i_iopen_gh);
+			return SHOULD_NOT_DELETE_DINODE;
+		}
+	}
+	return SHOULD_DELETE_DINODE;
+}
+
+/**
+ * evict_unlinked_inode - delete the pieces of an unlinked evicted inode
+ * @inode: The inode to evict
+ */
+static int evict_unlinked_inode(struct inode *inode)
+{
+	struct gfs2_inode *ip = GFS2_I(inode);
+	int ret;
+
+	if (S_ISDIR(inode->i_mode) &&
+	    (ip->i_diskflags & GFS2_DIF_EXHASH)) {
+		ret = gfs2_dir_exhash_dealloc(ip);
+		if (ret)
+			goto out;
+	}
+
+	if (ip->i_eattr) {
+		ret = gfs2_ea_dealloc(ip);
+		if (ret)
+			goto out;
+	}
+
+	if (!gfs2_is_stuffed(ip)) {
+		ret = gfs2_file_dealloc(ip);
+		if (ret)
+			goto out;
+	}
+
+	/*
+	 * As soon as we clear the bitmap for the dinode, gfs2_create_inode()
+	 * can get called to recreate it, or even gfs2_inode_lookup() if the
+	 * inode was recreated on another node in the meantime.
+	 *
+	 * However, inserting the new inode into the inode hash table will not
+	 * succeed until the old inode is removed, and that only happens after
+	 * ->evict_inode() returns.  The new inode is attached to its inode and
+	 *  iopen glocks after inserting it into the inode hash table, so at
+	 *  that point we can be sure that both glocks are unused.
+	 */
+
+	ret = gfs2_dinode_dealloc(ip);
+	if (!ret && ip->i_gl)
+		gfs2_inode_remember_delete(ip->i_gl, ip->i_no_formal_ino);
+
+out:
+	return ret;
+}
+
+/*
+ * evict_linked_inode - evict an inode whose dinode has not been unlinked
+ * @inode: The inode to evict
+ */
+static int evict_linked_inode(struct inode *inode)
+{
+	struct super_block *sb = inode->i_sb;
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct address_space *metamapping;
+	int ret;
+
+	gfs2_log_flush(sdp, ip->i_gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
+		       GFS2_LFC_EVICT_INODE);
+	metamapping = gfs2_glock2aspace(ip->i_gl);
+	if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
+		filemap_fdatawrite(metamapping);
+		filemap_fdatawait(metamapping);
+	}
+	write_inode_now(inode, 1);
+	gfs2_ail_flush(ip->i_gl, 0);
+
+	ret = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
+	if (ret)
+		return ret;
+
+	/* Needs to be done before glock release & also in a transaction */
+	truncate_inode_pages(&inode->i_data, 0);
+	truncate_inode_pages(metamapping, 0);
+	gfs2_trans_end(sdp);
+	return 0;
+}
+
+/**
+ * gfs2_evict_inode - Remove an inode from cache
+ * @inode: The inode to evict
+ *
+ * There are three cases to consider:
+ * 1. i_nlink == 0, we are final opener (and must deallocate)
+ * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
+ * 3. i_nlink > 0
+ *
+ * If the fs is read only, then we have to treat all cases as per #3
+ * since we are unable to do any deallocation. The inode will be
+ * deallocated by the next read/write node to attempt an allocation
+ * in the same resource group
+ *
+ * We have to (at the moment) hold the inodes main lock to cover
+ * the gap between unlocking the shared lock on the iopen lock and
+ * taking the exclusive lock. I'd rather do a shared -> exclusive
+ * conversion on the iopen lock, but we can change that later. This
+ * is safe, just less efficient.
+ */
+
+static void gfs2_evict_inode(struct inode *inode)
+{
+	struct super_block *sb = inode->i_sb;
+	struct gfs2_sbd *sdp = sb->s_fs_info;
+	struct gfs2_inode *ip = GFS2_I(inode);
+	struct gfs2_holder gh;
+	int ret;
+
+	if (inode->i_nlink || sb_rdonly(sb) || !ip->i_no_addr)
+		goto out;
+
+	/*
+	 * In case of an incomplete mount, gfs2_evict_inode() may be called for
+	 * system files without having an active journal to write to.  In that
+	 * case, skip the filesystem evict.
+	 */
+	if (!sdp->sd_jdesc)
+		goto out;
+
+	gfs2_holder_mark_uninitialized(&gh);
+	ret = evict_should_delete(inode, &gh);
+	if (ret == SHOULD_DEFER_EVICTION)
+		goto out;
+	if (ret == SHOULD_DELETE_DINODE)
+		ret = evict_unlinked_inode(inode);
+	else
+		ret = evict_linked_inode(inode);
+
+	if (gfs2_rs_active(&ip->i_res))
+		gfs2_rs_deltree(&ip->i_res);
+
+	if (gfs2_holder_initialized(&gh))
+		gfs2_glock_dq_uninit(&gh);
+	if (ret && ret != GLR_TRYFAILED && ret != -EROFS)
+		fs_warn(sdp, "gfs2_evict_inode: %d\n", ret);
+out:
+	truncate_inode_pages_final(&inode->i_data);
+	if (ip->i_qadata)
+		gfs2_assert_warn(sdp, ip->i_qadata->qa_ref == 0);
+	gfs2_rs_deltree(&ip->i_res);
+	gfs2_ordered_del_inode(ip);
+	clear_inode(inode);
+	gfs2_dir_hash_inval(ip);
+	if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
+		struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
+
+		glock_clear_object(gl, ip);
+		gfs2_glock_hold(gl);
+		ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
+		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
+		gfs2_glock_put_eventually(gl);
+	}
+	if (ip->i_gl) {
+		glock_clear_object(ip->i_gl, ip);
+		wait_on_bit_io(&ip->i_flags, GIF_GLOP_PENDING, TASK_UNINTERRUPTIBLE);
+		gfs2_glock_add_to_lru(ip->i_gl);
+		gfs2_glock_put_eventually(ip->i_gl);
+		rcu_assign_pointer(ip->i_gl, NULL);
+	}
+}
+
+static struct inode *gfs2_alloc_inode(struct super_block *sb)
+{
+	struct gfs2_inode *ip;
+
+	ip = alloc_inode_sb(sb, gfs2_inode_cachep, GFP_KERNEL);
+	if (!ip)
+		return NULL;
+	ip->i_no_addr = 0;
+	ip->i_flags = 0;
+	ip->i_gl = NULL;
+	gfs2_holder_mark_uninitialized(&ip->i_iopen_gh);
+	memset(&ip->i_res, 0, sizeof(ip->i_res));
+	RB_CLEAR_NODE(&ip->i_res.rs_node);
+	ip->i_rahead = 0;
+	return &ip->i_inode;
+}
+
+static void gfs2_free_inode(struct inode *inode)
+{
+	kmem_cache_free(gfs2_inode_cachep, GFS2_I(inode));
+}
+
+extern void free_local_statfs_inodes(struct gfs2_sbd *sdp)
+{
+	struct local_statfs_inode *lsi, *safe;
+
+	/* Run through the statfs inodes list to iput and free memory */
+	list_for_each_entry_safe(lsi, safe, &sdp->sd_sc_inodes_list, si_list) {
+		if (lsi->si_jid == sdp->sd_jdesc->jd_jid)
+			sdp->sd_sc_inode = NULL; /* belongs to this node */
+		if (lsi->si_sc_inode)
+			iput(lsi->si_sc_inode);
+		list_del(&lsi->si_list);
+		kfree(lsi);
+	}
+}
+
+extern struct inode *find_local_statfs_inode(struct gfs2_sbd *sdp,
+					     unsigned int index)
+{
+	struct local_statfs_inode *lsi;
+
+	/* Return the local (per node) statfs inode in the
+	 * sdp->sd_sc_inodes_list corresponding to the 'index'. */
+	list_for_each_entry(lsi, &sdp->sd_sc_inodes_list, si_list) {
+		if (lsi->si_jid == index)
+			return lsi->si_sc_inode;
+	}
+	return NULL;
+}
+
+const struct super_operations gfs2_super_ops = {
+	.alloc_inode		= gfs2_alloc_inode,
+	.free_inode		= gfs2_free_inode,
+	.write_inode		= gfs2_write_inode,
+	.dirty_inode		= gfs2_dirty_inode,
+	.evict_inode		= gfs2_evict_inode,
+	.put_super		= gfs2_put_super,
+	.sync_fs		= gfs2_sync_fs,
+	.freeze_super		= gfs2_freeze_super,
+	.thaw_super		= gfs2_thaw_super,
+	.statfs			= gfs2_statfs,
+	.drop_inode		= gfs2_drop_inode,
+	.show_options		= gfs2_show_options,
+};
+