1 files changed, 705 insertions, 0 deletions

diff --git a/fs/xfs/libxfs/xfs_dir2.c b/fs/xfs/libxfs/xfs_dir2.c
new file mode 100644
index 000000000..229152cd1
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_dir2.c
@@ -0,0 +1,705 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_defer.h"
+#include "xfs_da_format.h"
+#include "xfs_da_btree.h"
+#include "xfs_inode.h"
+#include "xfs_trans.h"
+#include "xfs_inode_item.h"
+#include "xfs_bmap.h"
+#include "xfs_dir2.h"
+#include "xfs_dir2_priv.h"
+#include "xfs_ialloc.h"
+#include "xfs_errortag.h"
+#include "xfs_error.h"
+#include "xfs_trace.h"
+
+struct xfs_name xfs_name_dotdot = { (unsigned char *)"..", 2, XFS_DIR3_FT_DIR };
+
+/*
+ * Convert inode mode to directory entry filetype
+ */
+unsigned char
+xfs_mode_to_ftype(
+	int		mode)
+{
+	switch (mode & S_IFMT) {
+	case S_IFREG:
+		return XFS_DIR3_FT_REG_FILE;
+	case S_IFDIR:
+		return XFS_DIR3_FT_DIR;
+	case S_IFCHR:
+		return XFS_DIR3_FT_CHRDEV;
+	case S_IFBLK:
+		return XFS_DIR3_FT_BLKDEV;
+	case S_IFIFO:
+		return XFS_DIR3_FT_FIFO;
+	case S_IFSOCK:
+		return XFS_DIR3_FT_SOCK;
+	case S_IFLNK:
+		return XFS_DIR3_FT_SYMLINK;
+	default:
+		return XFS_DIR3_FT_UNKNOWN;
+	}
+}
+
+/*
+ * ASCII case-insensitive (ie. A-Z) support for directories that was
+ * used in IRIX.
+ */
+STATIC xfs_dahash_t
+xfs_ascii_ci_hashname(
+	struct xfs_name	*name)
+{
+	xfs_dahash_t	hash;
+	int		i;
+
+	for (i = 0, hash = 0; i < name->len; i++)
+		hash = tolower(name->name[i]) ^ rol32(hash, 7);
+
+	return hash;
+}
+
+STATIC enum xfs_dacmp
+xfs_ascii_ci_compname(
+	struct xfs_da_args *args,
+	const unsigned char *name,
+	int		len)
+{
+	enum xfs_dacmp	result;
+	int		i;
+
+	if (args->namelen != len)
+		return XFS_CMP_DIFFERENT;
+
+	result = XFS_CMP_EXACT;
+	for (i = 0; i < len; i++) {
+		if (args->name[i] == name[i])
+			continue;
+		if (tolower(args->name[i]) != tolower(name[i]))
+			return XFS_CMP_DIFFERENT;
+		result = XFS_CMP_CASE;
+	}
+
+	return result;
+}
+
+static const struct xfs_nameops xfs_ascii_ci_nameops = {
+	.hashname	= xfs_ascii_ci_hashname,
+	.compname	= xfs_ascii_ci_compname,
+};
+
+int
+xfs_da_mount(
+	struct xfs_mount	*mp)
+{
+	struct xfs_da_geometry	*dageo;
+	int			nodehdr_size;
+
+
+	ASSERT(mp->m_sb.sb_versionnum & XFS_SB_VERSION_DIRV2BIT);
+	ASSERT(xfs_dir2_dirblock_bytes(&mp->m_sb) <= XFS_MAX_BLOCKSIZE);
+
+	mp->m_dir_inode_ops = xfs_dir_get_ops(mp, NULL);
+	mp->m_nondir_inode_ops = xfs_nondir_get_ops(mp, NULL);
+
+	nodehdr_size = mp->m_dir_inode_ops->node_hdr_size;
+	mp->m_dir_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
+				    KM_SLEEP | KM_MAYFAIL);
+	mp->m_attr_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
+				     KM_SLEEP | KM_MAYFAIL);
+	if (!mp->m_dir_geo || !mp->m_attr_geo) {
+		kmem_free(mp->m_dir_geo);
+		kmem_free(mp->m_attr_geo);
+		return -ENOMEM;
+	}
+
+	/* set up directory geometry */
+	dageo = mp->m_dir_geo;
+	dageo->blklog = mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog;
+	dageo->fsblog = mp->m_sb.sb_blocklog;
+	dageo->blksize = xfs_dir2_dirblock_bytes(&mp->m_sb);
+	dageo->fsbcount = 1 << mp->m_sb.sb_dirblklog;
+
+	/*
+	 * Now we've set up the block conversion variables, we can calculate the
+	 * segment block constants using the geometry structure.
+	 */
+	dageo->datablk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_DATA_OFFSET);
+	dageo->leafblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_LEAF_OFFSET);
+	dageo->freeblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_FREE_OFFSET);
+	dageo->node_ents = (dageo->blksize - nodehdr_size) /
+				(uint)sizeof(xfs_da_node_entry_t);
+	dageo->magicpct = (dageo->blksize * 37) / 100;
+
+	/* set up attribute geometry - single fsb only */
+	dageo = mp->m_attr_geo;
+	dageo->blklog = mp->m_sb.sb_blocklog;
+	dageo->fsblog = mp->m_sb.sb_blocklog;
+	dageo->blksize = 1 << dageo->blklog;
+	dageo->fsbcount = 1;
+	dageo->node_ents = (dageo->blksize - nodehdr_size) /
+				(uint)sizeof(xfs_da_node_entry_t);
+	dageo->magicpct = (dageo->blksize * 37) / 100;
+
+	if (xfs_sb_version_hasasciici(&mp->m_sb))
+		mp->m_dirnameops = &xfs_ascii_ci_nameops;
+	else
+		mp->m_dirnameops = &xfs_default_nameops;
+
+	return 0;
+}
+
+void
+xfs_da_unmount(
+	struct xfs_mount	*mp)
+{
+	kmem_free(mp->m_dir_geo);
+	kmem_free(mp->m_attr_geo);
+}
+
+/*
+ * Return 1 if directory contains only "." and "..".
+ */
+int
+xfs_dir_isempty(
+	xfs_inode_t	*dp)
+{
+	xfs_dir2_sf_hdr_t	*sfp;
+
+	ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
+	if (dp->i_d.di_size == 0)	/* might happen during shutdown. */
+		return 1;
+	if (dp->i_d.di_size > XFS_IFORK_DSIZE(dp))
+		return 0;
+	sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
+	return !sfp->count;
+}
+
+/*
+ * Validate a given inode number.
+ */
+int
+xfs_dir_ino_validate(
+	xfs_mount_t	*mp,
+	xfs_ino_t	ino)
+{
+	bool		ino_ok = xfs_verify_dir_ino(mp, ino);
+
+	if (unlikely(XFS_TEST_ERROR(!ino_ok, mp, XFS_ERRTAG_DIR_INO_VALIDATE))) {
+		xfs_warn(mp, "Invalid inode number 0x%Lx",
+				(unsigned long long) ino);
+		XFS_ERROR_REPORT("xfs_dir_ino_validate", XFS_ERRLEVEL_LOW, mp);
+		return -EFSCORRUPTED;
+	}
+	return 0;
+}
+
+/*
+ * Initialize a directory with its "." and ".." entries.
+ */
+int
+xfs_dir_init(
+	xfs_trans_t	*tp,
+	xfs_inode_t	*dp,
+	xfs_inode_t	*pdp)
+{
+	struct xfs_da_args *args;
+	int		error;
+
+	ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
+	error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino);
+	if (error)
+		return error;
+
+	args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
+	if (!args)
+		return -ENOMEM;
+
+	args->geo = dp->i_mount->m_dir_geo;
+	args->dp = dp;
+	args->trans = tp;
+	error = xfs_dir2_sf_create(args, pdp->i_ino);
+	kmem_free(args);
+	return error;
+}
+
+/*
+ * Enter a name in a directory, or check for available space.
+ * If inum is 0, only the available space test is performed.
+ */
+int
+xfs_dir_createname(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*dp,
+	struct xfs_name		*name,
+	xfs_ino_t		inum,		/* new entry inode number */
+	xfs_extlen_t		total)		/* bmap's total block count */
+{
+	struct xfs_da_args	*args;
+	int			rval;
+	int			v;		/* type-checking value */
+
+	ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
+
+	if (inum) {
+		rval = xfs_dir_ino_validate(tp->t_mountp, inum);
+		if (rval)
+			return rval;
+		XFS_STATS_INC(dp->i_mount, xs_dir_create);
+	}
+
+	args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
+	if (!args)
+		return -ENOMEM;
+
+	args->geo = dp->i_mount->m_dir_geo;
+	args->name = name->name;
+	args->namelen = name->len;
+	args->filetype = name->type;
+	args->hashval = dp->i_mount->m_dirnameops->hashname(name);
+	args->inumber = inum;
+	args->dp = dp;
+	args->total = total;
+	args->whichfork = XFS_DATA_FORK;
+	args->trans = tp;
+	args->op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
+	if (!inum)
+		args->op_flags |= XFS_DA_OP_JUSTCHECK;
+
+	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
+		rval = xfs_dir2_sf_addname(args);
+		goto out_free;
+	}
+
+	rval = xfs_dir2_isblock(args, &v);
+	if (rval)
+		goto out_free;
+	if (v) {
+		rval = xfs_dir2_block_addname(args);
+		goto out_free;
+	}
+
+	rval = xfs_dir2_isleaf(args, &v);
+	if (rval)
+		goto out_free;
+	if (v)
+		rval = xfs_dir2_leaf_addname(args);
+	else
+		rval = xfs_dir2_node_addname(args);
+
+out_free:
+	kmem_free(args);
+	return rval;
+}
+
+/*
+ * If doing a CI lookup and case-insensitive match, dup actual name into
+ * args.value. Return EEXIST for success (ie. name found) or an error.
+ */
+int
+xfs_dir_cilookup_result(
+	struct xfs_da_args *args,
+	const unsigned char *name,
+	int		len)
+{
+	if (args->cmpresult == XFS_CMP_DIFFERENT)
+		return -ENOENT;
+	if (args->cmpresult != XFS_CMP_CASE ||
+					!(args->op_flags & XFS_DA_OP_CILOOKUP))
+		return -EEXIST;
+
+	args->value = kmem_alloc(len, KM_NOFS | KM_MAYFAIL);
+	if (!args->value)
+		return -ENOMEM;
+
+	memcpy(args->value, name, len);
+	args->valuelen = len;
+	return -EEXIST;
+}
+
+/*
+ * Lookup a name in a directory, give back the inode number.
+ * If ci_name is not NULL, returns the actual name in ci_name if it differs
+ * to name, or ci_name->name is set to NULL for an exact match.
+ */
+
+int
+xfs_dir_lookup(
+	xfs_trans_t	*tp,
+	xfs_inode_t	*dp,
+	struct xfs_name	*name,
+	xfs_ino_t	*inum,		/* out: inode number */
+	struct xfs_name *ci_name)	/* out: actual name if CI match */
+{
+	struct xfs_da_args *args;
+	int		rval;
+	int		v;		/* type-checking value */
+	int		lock_mode;
+
+	ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
+	XFS_STATS_INC(dp->i_mount, xs_dir_lookup);
+
+	/*
+	 * We need to use KM_NOFS here so that lockdep will not throw false
+	 * positive deadlock warnings on a non-transactional lookup path. It is
+	 * safe to recurse into inode recalim in that case, but lockdep can't
+	 * easily be taught about it. Hence KM_NOFS avoids having to add more
+	 * lockdep Doing this avoids having to add a bunch of lockdep class
+	 * annotations into the reclaim path for the ilock.
+	 */
+	args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
+	args->geo = dp->i_mount->m_dir_geo;
+	args->name = name->name;
+	args->namelen = name->len;
+	args->filetype = name->type;
+	args->hashval = dp->i_mount->m_dirnameops->hashname(name);
+	args->dp = dp;
+	args->whichfork = XFS_DATA_FORK;
+	args->trans = tp;
+	args->op_flags = XFS_DA_OP_OKNOENT;
+	if (ci_name)
+		args->op_flags |= XFS_DA_OP_CILOOKUP;
+
+	lock_mode = xfs_ilock_data_map_shared(dp);
+	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
+		rval = xfs_dir2_sf_lookup(args);
+		goto out_check_rval;
+	}
+
+	rval = xfs_dir2_isblock(args, &v);
+	if (rval)
+		goto out_free;
+	if (v) {
+		rval = xfs_dir2_block_lookup(args);
+		goto out_check_rval;
+	}
+
+	rval = xfs_dir2_isleaf(args, &v);
+	if (rval)
+		goto out_free;
+	if (v)
+		rval = xfs_dir2_leaf_lookup(args);
+	else
+		rval = xfs_dir2_node_lookup(args);
+
+out_check_rval:
+	if (rval == -EEXIST)
+		rval = 0;
+	if (!rval) {
+		*inum = args->inumber;
+		if (ci_name) {
+			ci_name->name = args->value;
+			ci_name->len = args->valuelen;
+		}
+	}
+out_free:
+	xfs_iunlock(dp, lock_mode);
+	kmem_free(args);
+	return rval;
+}
+
+/*
+ * Remove an entry from a directory.
+ */
+int
+xfs_dir_removename(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*dp,
+	struct xfs_name		*name,
+	xfs_ino_t		ino,
+	xfs_extlen_t		total)		/* bmap's total block count */
+{
+	struct xfs_da_args	*args;
+	int			rval;
+	int			v;		/* type-checking value */
+
+	ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
+	XFS_STATS_INC(dp->i_mount, xs_dir_remove);
+
+	args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
+	if (!args)
+		return -ENOMEM;
+
+	args->geo = dp->i_mount->m_dir_geo;
+	args->name = name->name;
+	args->namelen = name->len;
+	args->filetype = name->type;
+	args->hashval = dp->i_mount->m_dirnameops->hashname(name);
+	args->inumber = ino;
+	args->dp = dp;
+	args->total = total;
+	args->whichfork = XFS_DATA_FORK;
+	args->trans = tp;
+
+	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
+		rval = xfs_dir2_sf_removename(args);
+		goto out_free;
+	}
+
+	rval = xfs_dir2_isblock(args, &v);
+	if (rval)
+		goto out_free;
+	if (v) {
+		rval = xfs_dir2_block_removename(args);
+		goto out_free;
+	}
+
+	rval = xfs_dir2_isleaf(args, &v);
+	if (rval)
+		goto out_free;
+	if (v)
+		rval = xfs_dir2_leaf_removename(args);
+	else
+		rval = xfs_dir2_node_removename(args);
+out_free:
+	kmem_free(args);
+	return rval;
+}
+
+/*
+ * Replace the inode number of a directory entry.
+ */
+int
+xfs_dir_replace(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*dp,
+	struct xfs_name		*name,		/* name of entry to replace */
+	xfs_ino_t		inum,		/* new inode number */
+	xfs_extlen_t		total)		/* bmap's total block count */
+{
+	struct xfs_da_args	*args;
+	int			rval;
+	int			v;		/* type-checking value */
+
+	ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
+
+	rval = xfs_dir_ino_validate(tp->t_mountp, inum);
+	if (rval)
+		return rval;
+
+	args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
+	if (!args)
+		return -ENOMEM;
+
+	args->geo = dp->i_mount->m_dir_geo;
+	args->name = name->name;
+	args->namelen = name->len;
+	args->filetype = name->type;
+	args->hashval = dp->i_mount->m_dirnameops->hashname(name);
+	args->inumber = inum;
+	args->dp = dp;
+	args->total = total;
+	args->whichfork = XFS_DATA_FORK;
+	args->trans = tp;
+
+	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
+		rval = xfs_dir2_sf_replace(args);
+		goto out_free;
+	}
+
+	rval = xfs_dir2_isblock(args, &v);
+	if (rval)
+		goto out_free;
+	if (v) {
+		rval = xfs_dir2_block_replace(args);
+		goto out_free;
+	}
+
+	rval = xfs_dir2_isleaf(args, &v);
+	if (rval)
+		goto out_free;
+	if (v)
+		rval = xfs_dir2_leaf_replace(args);
+	else
+		rval = xfs_dir2_node_replace(args);
+out_free:
+	kmem_free(args);
+	return rval;
+}
+
+/*
+ * See if this entry can be added to the directory without allocating space.
+ */
+int
+xfs_dir_canenter(
+	xfs_trans_t	*tp,
+	xfs_inode_t	*dp,
+	struct xfs_name	*name)		/* name of entry to add */
+{
+	return xfs_dir_createname(tp, dp, name, 0, 0);
+}
+
+/*
+ * Utility routines.
+ */
+
+/*
+ * Add a block to the directory.
+ *
+ * This routine is for data and free blocks, not leaf/node blocks which are
+ * handled by xfs_da_grow_inode.
+ */
+int
+xfs_dir2_grow_inode(
+	struct xfs_da_args	*args,
+	int			space,	/* v2 dir's space XFS_DIR2_xxx_SPACE */
+	xfs_dir2_db_t		*dbp)	/* out: block number added */
+{
+	struct xfs_inode	*dp = args->dp;
+	struct xfs_mount	*mp = dp->i_mount;
+	xfs_fileoff_t		bno;	/* directory offset of new block */
+	int			count;	/* count of filesystem blocks */
+	int			error;
+
+	trace_xfs_dir2_grow_inode(args, space);
+
+	/*
+	 * Set lowest possible block in the space requested.
+	 */
+	bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
+	count = args->geo->fsbcount;
+
+	error = xfs_da_grow_inode_int(args, &bno, count);
+	if (error)
+		return error;
+
+	*dbp = xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)bno);
+
+	/*
+	 * Update file's size if this is the data space and it grew.
+	 */
+	if (space == XFS_DIR2_DATA_SPACE) {
+		xfs_fsize_t	size;		/* directory file (data) size */
+
+		size = XFS_FSB_TO_B(mp, bno + count);
+		if (size > dp->i_d.di_size) {
+			dp->i_d.di_size = size;
+			xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE);
+		}
+	}
+	return 0;
+}
+
+/*
+ * See if the directory is a single-block form directory.
+ */
+int
+xfs_dir2_isblock(
+	struct xfs_da_args	*args,
+	int			*vp)	/* out: 1 is block, 0 is not block */
+{
+	xfs_fileoff_t		last;	/* last file offset */
+	int			rval;
+
+	if ((rval = xfs_bmap_last_offset(args->dp, &last, XFS_DATA_FORK)))
+		return rval;
+	rval = XFS_FSB_TO_B(args->dp->i_mount, last) == args->geo->blksize;
+	if (rval != 0 && args->dp->i_d.di_size != args->geo->blksize)
+		return -EFSCORRUPTED;
+	*vp = rval;
+	return 0;
+}
+
+/*
+ * See if the directory is a single-leaf form directory.
+ */
+int
+xfs_dir2_isleaf(
+	struct xfs_da_args	*args,
+	int			*vp)	/* out: 1 is block, 0 is not block */
+{
+	xfs_fileoff_t		last;	/* last file offset */
+	int			rval;
+
+	if ((rval = xfs_bmap_last_offset(args->dp, &last, XFS_DATA_FORK)))
+		return rval;
+	*vp = last == args->geo->leafblk + args->geo->fsbcount;
+	return 0;
+}
+
+/*
+ * Remove the given block from the directory.
+ * This routine is used for data and free blocks, leaf/node are done
+ * by xfs_da_shrink_inode.
+ */
+int
+xfs_dir2_shrink_inode(
+	struct xfs_da_args	*args,
+	xfs_dir2_db_t		db,
+	struct xfs_buf		*bp)
+{
+	xfs_fileoff_t		bno;		/* directory file offset */
+	xfs_dablk_t		da;		/* directory file offset */
+	int			done;		/* bunmap is finished */
+	struct xfs_inode	*dp;
+	int			error;
+	struct xfs_mount	*mp;
+	struct xfs_trans	*tp;
+
+	trace_xfs_dir2_shrink_inode(args, db);
+
+	dp = args->dp;
+	mp = dp->i_mount;
+	tp = args->trans;
+	da = xfs_dir2_db_to_da(args->geo, db);
+
+	/* Unmap the fsblock(s). */
+	error = xfs_bunmapi(tp, dp, da, args->geo->fsbcount, 0, 0, &done);
+	if (error) {
+		/*
+		 * ENOSPC actually can happen if we're in a removename with no
+		 * space reservation, and the resulting block removal would
+		 * cause a bmap btree split or conversion from extents to btree.
+		 * This can only happen for un-fragmented directory blocks,
+		 * since you need to be punching out the middle of an extent.
+		 * In this case we need to leave the block in the file, and not
+		 * binval it.  So the block has to be in a consistent empty
+		 * state and appropriately logged.  We don't free up the buffer,
+		 * the caller can tell it hasn't happened since it got an error
+		 * back.
+		 */
+		return error;
+	}
+	ASSERT(done);
+	/*
+	 * Invalidate the buffer from the transaction.
+	 */
+	xfs_trans_binval(tp, bp);
+	/*
+	 * If it's not a data block, we're done.
+	 */
+	if (db >= xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET))
+		return 0;
+	/*
+	 * If the block isn't the last one in the directory, we're done.
+	 */
+	if (dp->i_d.di_size > xfs_dir2_db_off_to_byte(args->geo, db + 1, 0))
+		return 0;
+	bno = da;
+	if ((error = xfs_bmap_last_before(tp, dp, &bno, XFS_DATA_FORK))) {
+		/*
+		 * This can't really happen unless there's kernel corruption.
+		 */
+		return error;
+	}
+	if (db == args->geo->datablk)
+		ASSERT(bno == 0);
+	else
+		ASSERT(bno > 0);
+	/*
+	 * Set the size to the new last block.
+	 */
+	dp->i_d.di_size = XFS_FSB_TO_B(mp, bno);
+	xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
+	return 0;
+}