// 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_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_bmap.h"
#include "xfs_dir2.h"
#include "xfs_dir2_priv.h"
#include "xfs_errortag.h"
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_health.h"
#include "xfs_bmap_btree.h"
#include "xfs_trans_space.h"
#include "xfs_parent.h"
#include "xfs_ag.h"
#include "xfs_ialloc.h"
const struct xfs_name xfs_name_dotdot = {
.name = (const unsigned char *)"..",
.len = 2,
.type = XFS_DIR3_FT_DIR,
};
const struct xfs_name xfs_name_dot = {
.name = (const unsigned char *)".",
.len = 1,
.type = 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.
*/
xfs_dahash_t
xfs_ascii_ci_hashname(
const struct xfs_name *name)
{
xfs_dahash_t hash;
int i;
for (i = 0, hash = 0; i < name->len; i++)
hash = xfs_ascii_ci_xfrm(name->name[i]) ^ rol32(hash, 7);
return hash;
}
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 (xfs_ascii_ci_xfrm(args->name[i]) !=
xfs_ascii_ci_xfrm(name[i]))
return XFS_CMP_DIFFERENT;
result = XFS_CMP_CASE;
}
return result;
}
int
xfs_da_mount(
struct xfs_mount *mp)
{
struct xfs_da_geometry *dageo;
ASSERT(mp->m_sb.sb_versionnum & XFS_SB_VERSION_DIRV2BIT);
ASSERT(xfs_dir2_dirblock_bytes(&mp->m_sb) <= XFS_MAX_BLOCKSIZE);
mp->m_dir_geo = kzalloc(sizeof(struct xfs_da_geometry),
GFP_KERNEL | __GFP_RETRY_MAYFAIL);
mp->m_attr_geo = kzalloc(sizeof(struct xfs_da_geometry),
GFP_KERNEL | __GFP_RETRY_MAYFAIL);
if (!mp->m_dir_geo || !mp->m_attr_geo) {
kfree(mp->m_dir_geo);
kfree(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;
if (xfs_has_crc(mp)) {
dageo->node_hdr_size = sizeof(struct xfs_da3_node_hdr);
dageo->leaf_hdr_size = sizeof(struct xfs_dir3_leaf_hdr);
dageo->free_hdr_size = sizeof(struct xfs_dir3_free_hdr);
dageo->data_entry_offset =
sizeof(struct xfs_dir3_data_hdr);
} else {
dageo->node_hdr_size = sizeof(struct xfs_da_node_hdr);
dageo->leaf_hdr_size = sizeof(struct xfs_dir2_leaf_hdr);
dageo->free_hdr_size = sizeof(struct xfs_dir2_free_hdr);
dageo->data_entry_offset =
sizeof(struct xfs_dir2_data_hdr);
}
dageo->leaf_max_ents = (dageo->blksize - dageo->leaf_hdr_size) /
sizeof(struct xfs_dir2_leaf_entry);
dageo->free_max_bests = (dageo->blksize - dageo->free_hdr_size) /
sizeof(xfs_dir2_data_off_t);
dageo->data_first_offset = dageo->data_entry_offset +
xfs_dir2_data_entsize(mp, 1) +
xfs_dir2_data_entsize(mp, 2);
/*
* 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 - dageo->node_hdr_size) /
(uint)sizeof(xfs_da_node_entry_t);
dageo->max_extents = (XFS_DIR2_MAX_SPACES * XFS_DIR2_SPACE_SIZE) >>
mp->m_sb.sb_blocklog;
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_hdr_size = mp->m_dir_geo->node_hdr_size;
dageo->node_ents = (dageo->blksize - dageo->node_hdr_size) /
(uint)sizeof(xfs_da_node_entry_t);
if (xfs_has_large_extent_counts(mp))
dageo->max_extents = XFS_MAX_EXTCNT_ATTR_FORK_LARGE;
else
dageo->max_extents = XFS_MAX_EXTCNT_ATTR_FORK_SMALL;
dageo->magicpct = (dageo->blksize * 37) / 100;
return 0;
}
void
xfs_da_unmount(
struct xfs_mount *mp)
{
kfree(mp->m_dir_geo);
kfree(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_disk_size == 0) /* might happen during shutdown. */
return 1;
if (dp->i_disk_size > xfs_inode_data_fork_size(dp))
return 0;
sfp = dp->i_df.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 (XFS_IS_CORRUPT(mp, !ino_ok) ||
XFS_TEST_ERROR(false, mp, XFS_ERRTAG_DIR_INO_VALIDATE)) {
xfs_warn(mp, "Invalid inode number 0x%Lx",
(unsigned long long) ino);
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 = kzalloc(sizeof(*args), GFP_KERNEL | __GFP_NOFAIL);
if (!args)
return -ENOMEM;
args->geo = dp->i_mount->m_dir_geo;
args->dp = dp;
args->trans = tp;
args->owner = dp->i_ino;
error = xfs_dir2_sf_create(args, pdp->i_ino);
kfree(args);
return error;
}
enum xfs_dir2_fmt
xfs_dir2_format(
struct xfs_da_args *args,
int *error)
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
struct xfs_da_geometry *geo = mp->m_dir_geo;
xfs_fileoff_t eof;
xfs_assert_ilocked(dp, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL);
*error = 0;
if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL)
return XFS_DIR2_FMT_SF;
*error = xfs_bmap_last_offset(dp, &eof, XFS_DATA_FORK);
if (*error)
return XFS_DIR2_FMT_ERROR;
if (eof == XFS_B_TO_FSB(mp, geo->blksize)) {
if (XFS_IS_CORRUPT(mp, dp->i_disk_size != geo->blksize)) {
xfs_da_mark_sick(args);
*error = -EFSCORRUPTED;
return XFS_DIR2_FMT_ERROR;
}
return XFS_DIR2_FMT_BLOCK;
}
if (eof == geo->leafblk + geo->fsbcount)
return XFS_DIR2_FMT_LEAF;
return XFS_DIR2_FMT_NODE;
}
int
xfs_dir_createname_args(
struct xfs_da_args *args)
{
int error;
if (!args->inumber)
args->op_flags |= XFS_DA_OP_JUSTCHECK;
switch (xfs_dir2_format(args, &error)) {
case XFS_DIR2_FMT_SF:
return xfs_dir2_sf_addname(args);
case XFS_DIR2_FMT_BLOCK:
return xfs_dir2_block_addname(args);
case XFS_DIR2_FMT_LEAF:
return xfs_dir2_leaf_addname(args);
case XFS_DIR2_FMT_NODE:
return xfs_dir2_node_addname(args);
default:
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,
const 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;
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 = kzalloc(sizeof(*args), GFP_KERNEL | __GFP_NOFAIL);
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 = xfs_dir2_hashname(dp->i_mount, 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;
args->owner = dp->i_ino;
rval = xfs_dir_createname_args(args);
kfree(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 = kmalloc(len,
GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_RETRY_MAYFAIL);
if (!args->value)
return -ENOMEM;
memcpy(args->value, name, len);
args->valuelen = len;
return -EEXIST;
}
int
xfs_dir_lookup_args(
struct xfs_da_args *args)
{
int error;
switch (xfs_dir2_format(args, &error)) {
case XFS_DIR2_FMT_SF:
error = xfs_dir2_sf_lookup(args);
break;
case XFS_DIR2_FMT_BLOCK:
error = xfs_dir2_block_lookup(args);
break;
case XFS_DIR2_FMT_LEAF:
error = xfs_dir2_leaf_lookup(args);
break;
case XFS_DIR2_FMT_NODE:
error = xfs_dir2_node_lookup(args);
break;
default:
break;
}
if (error != -EEXIST)
return error;
return 0;
}
/*
* 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(
struct xfs_trans *tp,
struct xfs_inode *dp,
const 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 lock_mode;
ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
XFS_STATS_INC(dp->i_mount, xs_dir_lookup);
args = kzalloc(sizeof(*args),
GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
args->geo = dp->i_mount->m_dir_geo;
args->name = name->name;
args->namelen = name->len;
args->filetype = name->type;
args->hashval = xfs_dir2_hashname(dp->i_mount, name);
args->dp = dp;
args->whichfork = XFS_DATA_FORK;
args->trans = tp;
args->op_flags = XFS_DA_OP_OKNOENT;
args->owner = dp->i_ino;
if (ci_name)
args->op_flags |= XFS_DA_OP_CILOOKUP;
lock_mode = xfs_ilock_data_map_shared(dp);
rval = xfs_dir_lookup_args(args);
if (!rval) {
*inum = args->inumber;
if (ci_name) {
ci_name->name = args->value;
ci_name->len = args->valuelen;
}
}
xfs_iunlock(dp, lock_mode);
kfree(args);
return rval;
}
int
xfs_dir_removename_args(
struct xfs_da_args *args)
{
int error;
switch (xfs_dir2_format(args, &error)) {
case XFS_DIR2_FMT_SF:
return xfs_dir2_sf_removename(args);
case XFS_DIR2_FMT_BLOCK:
return xfs_dir2_block_removename(args);
case XFS_DIR2_FMT_LEAF:
return xfs_dir2_leaf_removename(args);
case XFS_DIR2_FMT_NODE:
return xfs_dir2_node_removename(args);
default:
return error;
}
}
/*
* Remove an entry from a directory.
*/
int
xfs_dir_removename(
struct xfs_trans *tp,
struct xfs_inode *dp,
const struct xfs_name *name,
xfs_ino_t ino,
xfs_extlen_t total) /* bmap's total block count */
{
struct xfs_da_args *args;
int rval;
ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
XFS_STATS_INC(dp->i_mount, xs_dir_remove);
args = kzalloc(sizeof(*args), GFP_KERNEL | __GFP_NOFAIL);
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 = xfs_dir2_hashname(dp->i_mount, name);
args->inumber = ino;
args->dp = dp;
args->total = total;
args->whichfork = XFS_DATA_FORK;
args->trans = tp;
args->owner = dp->i_ino;
rval = xfs_dir_removename_args(args);
kfree(args);
return rval;
}
int
xfs_dir_replace_args(
struct xfs_da_args *args)
{
int error;
switch (xfs_dir2_format(args, &error)) {
case XFS_DIR2_FMT_SF:
return xfs_dir2_sf_replace(args);
case XFS_DIR2_FMT_BLOCK:
return xfs_dir2_block_replace(args);
case XFS_DIR2_FMT_LEAF:
return xfs_dir2_leaf_replace(args);
case XFS_DIR2_FMT_NODE:
return xfs_dir2_node_replace(args);
default:
return error;
}
}
/*
* Replace the inode number of a directory entry.
*/
int
xfs_dir_replace(
struct xfs_trans *tp,
struct xfs_inode *dp,
const 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;
ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
rval = xfs_dir_ino_validate(tp->t_mountp, inum);
if (rval)
return rval;
args = kzalloc(sizeof(*args), GFP_KERNEL | __GFP_NOFAIL);
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 = xfs_dir2_hashname(dp->i_mount, name);
args->inumber = inum;
args->dp = dp;
args->total = total;
args->whichfork = XFS_DATA_FORK;
args->trans = tp;
args->owner = dp->i_ino;
rval = xfs_dir_replace_args(args);
kfree(args);
return rval;
}
/*
* See if this entry can be added to the directory without allocating space.
*/
int
xfs_dir_canenter(
struct xfs_trans *tp,
struct xfs_inode *dp,
const 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_disk_size) {
dp->i_disk_size = size;
xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE);
}
}
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_disk_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_disk_size = XFS_FSB_TO_B(mp, bno);
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
return 0;
}
/* Returns true if the directory entry name is valid. */
bool
xfs_dir2_namecheck(
const void *name,
size_t length)
{
/*
* MAXNAMELEN includes the trailing null, but (name/length) leave it
* out, so use >= for the length check.
*/
if (length >= MAXNAMELEN)
return false;
/* There shouldn't be any slashes or nulls here */
return !memchr(name, '/', length) && !memchr(name, 0, length);
}
xfs_dahash_t
xfs_dir2_hashname(
struct xfs_mount *mp,
const struct xfs_name *name)
{
if (unlikely(xfs_has_asciici(mp)))
return xfs_ascii_ci_hashname(name);
return xfs_da_hashname(name->name, name->len);
}
enum xfs_dacmp
xfs_dir2_compname(
struct xfs_da_args *args,
const unsigned char *name,
int len)
{
if (unlikely(xfs_has_asciici(args->dp->i_mount)))
return xfs_ascii_ci_compname(args, name, len);
return xfs_da_compname(args, name, len);
}
#ifdef CONFIG_XFS_LIVE_HOOKS
/*
* Use a static key here to reduce the overhead of directory live update hooks.
* If the compiler supports jump labels, the static branch will be replaced by
* a nop sled when there are no hook users. Online fsck is currently the only
* caller, so this is a reasonable tradeoff.
*
* Note: Patching the kernel code requires taking the cpu hotplug lock. Other
* parts of the kernel allocate memory with that lock held, which means that
* XFS callers cannot hold any locks that might be used by memory reclaim or
* writeback when calling the static_branch_{inc,dec} functions.
*/
DEFINE_STATIC_XFS_HOOK_SWITCH(xfs_dir_hooks_switch);
void
xfs_dir_hook_disable(void)
{
xfs_hooks_switch_off(&xfs_dir_hooks_switch);
}
void
xfs_dir_hook_enable(void)
{
xfs_hooks_switch_on(&xfs_dir_hooks_switch);
}
/* Call hooks for a directory update relating to a child dirent update. */
inline void
xfs_dir_update_hook(
struct xfs_inode *dp,
struct xfs_inode *ip,
int delta,
const struct xfs_name *name)
{
if (xfs_hooks_switched_on(&xfs_dir_hooks_switch)) {
struct xfs_dir_update_params p = {
.dp = dp,
.ip = ip,
.delta = delta,
.name = name,
};
struct xfs_mount *mp = ip->i_mount;
xfs_hooks_call(&mp->m_dir_update_hooks, 0, &p);
}
}
/* Call the specified function during a directory update. */
int
xfs_dir_hook_add(
struct xfs_mount *mp,
struct xfs_dir_hook *hook)
{
return xfs_hooks_add(&mp->m_dir_update_hooks, &hook->dirent_hook);
}
/* Stop calling the specified function during a directory update. */
void
xfs_dir_hook_del(
struct xfs_mount *mp,
struct xfs_dir_hook *hook)
{
xfs_hooks_del(&mp->m_dir_update_hooks, &hook->dirent_hook);
}
/* Configure directory update hook functions. */
void
xfs_dir_hook_setup(
struct xfs_dir_hook *hook,
notifier_fn_t mod_fn)
{
xfs_hook_setup(&hook->dirent_hook, mod_fn);
}
#endif /* CONFIG_XFS_LIVE_HOOKS */
/*
* Given a directory @dp, a newly allocated inode @ip, and a @name, link @ip
* into @dp under the given @name. If @ip is a directory, it will be
* initialized. Both inodes must have the ILOCK held and the transaction must
* have sufficient blocks reserved.
*/
int
xfs_dir_create_child(
struct xfs_trans *tp,
unsigned int resblks,
struct xfs_dir_update *du)
{
struct xfs_inode *dp = du->dp;
const struct xfs_name *name = du->name;
struct xfs_inode *ip = du->ip;
int error;
xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
xfs_assert_ilocked(dp, XFS_ILOCK_EXCL);
error = xfs_dir_createname(tp, dp, name, ip->i_ino, resblks);
if (error) {
ASSERT(error != -ENOSPC);
return error;
}
xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
if (S_ISDIR(VFS_I(ip)->i_mode)) {
error = xfs_dir_init(tp, ip, dp);
if (error)
return error;
xfs_bumplink(tp, dp);
}
/*
* If we have parent pointers, we need to add the attribute containing
* the parent information now.
*/
if (du->ppargs) {
error = xfs_parent_addname(tp, du->ppargs, dp, name, ip);
if (error)
return error;
}
xfs_dir_update_hook(dp, ip, 1, name);
return 0;
}
/*
* Given a directory @dp, an existing non-directory inode @ip, and a @name,
* link @ip into @dp under the given @name. Both inodes must have the ILOCK
* held.
*/
int
xfs_dir_add_child(
struct xfs_trans *tp,
unsigned int resblks,
struct xfs_dir_update *du)
{
struct xfs_inode *dp = du->dp;
const struct xfs_name *name = du->name;
struct xfs_inode *ip = du->ip;
struct xfs_mount *mp = tp->t_mountp;
int error;
xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
xfs_assert_ilocked(dp, XFS_ILOCK_EXCL);
ASSERT(!S_ISDIR(VFS_I(ip)->i_mode));
if (!resblks) {
error = xfs_dir_canenter(tp, dp, name);
if (error)
return error;
}
/*
* Handle initial link state of O_TMPFILE inode
*/
if (VFS_I(ip)->i_nlink == 0) {
struct xfs_perag *pag;
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
error = xfs_iunlink_remove(tp, pag, ip);
xfs_perag_put(pag);
if (error)
return error;
}
error = xfs_dir_createname(tp, dp, name, ip->i_ino, resblks);
if (error)
return error;
xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
xfs_bumplink(tp, ip);
/*
* If we have parent pointers, we now need to add the parent record to
* the attribute fork of the inode. If this is the initial parent
* attribute, we need to create it correctly, otherwise we can just add
* the parent to the inode.
*/
if (du->ppargs) {
error = xfs_parent_addname(tp, du->ppargs, dp, name, ip);
if (error)
return error;
}
xfs_dir_update_hook(dp, ip, 1, name);
return 0;
}
/*
* Given a directory @dp, a child @ip, and a @name, remove the (@name, @ip)
* entry from the directory. Both inodes must have the ILOCK held.
*/
int
xfs_dir_remove_child(
struct xfs_trans *tp,
unsigned int resblks,
struct xfs_dir_update *du)
{
struct xfs_inode *dp = du->dp;
const struct xfs_name *name = du->name;
struct xfs_inode *ip = du->ip;
int error;
xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
xfs_assert_ilocked(dp, XFS_ILOCK_EXCL);
/*
* If we're removing a directory perform some additional validation.
*/
if (S_ISDIR(VFS_I(ip)->i_mode)) {
ASSERT(VFS_I(ip)->i_nlink >= 2);
if (VFS_I(ip)->i_nlink != 2)
return -ENOTEMPTY;
if (!xfs_dir_isempty(ip))
return -ENOTEMPTY;
/* Drop the link from ip's "..". */
error = xfs_droplink(tp, dp);
if (error)
return error;
/* Drop the "." link from ip to self. */
error = xfs_droplink(tp, ip);
if (error)
return error;
/*
* Point the unlinked child directory's ".." entry to the root
* directory to eliminate back-references to inodes that may
* get freed before the child directory is closed. If the fs
* gets shrunk, this can lead to dirent inode validation errors.
*/
if (dp->i_ino != tp->t_mountp->m_sb.sb_rootino) {
error = xfs_dir_replace(tp, ip, &xfs_name_dotdot,
tp->t_mountp->m_sb.sb_rootino, 0);
if (error)
return error;
}
} else {
/*
* When removing a non-directory we need to log the parent
* inode here. For a directory this is done implicitly
* by the xfs_droplink call for the ".." entry.
*/
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
}
xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
/* Drop the link from dp to ip. */
error = xfs_droplink(tp, ip);
if (error)
return error;
error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks);
if (error) {
ASSERT(error != -ENOENT);
return error;
}
/* Remove parent pointer. */
if (du->ppargs) {
error = xfs_parent_removename(tp, du->ppargs, dp, name, ip);
if (error)
return error;
}
xfs_dir_update_hook(dp, ip, -1, name);
return 0;
}
/*
* Exchange the entry (@name1, @ip1) in directory @dp1 with the entry (@name2,
* @ip2) in directory @dp2, and update '..' @ip1 and @ip2's entries as needed.
* @ip1 and @ip2 need not be of the same type.
*
* All inodes must have the ILOCK held, and both entries must already exist.
*/
int
xfs_dir_exchange_children(
struct xfs_trans *tp,
struct xfs_dir_update *du1,
struct xfs_dir_update *du2,
unsigned int spaceres)
{
struct xfs_inode *dp1 = du1->dp;
const struct xfs_name *name1 = du1->name;
struct xfs_inode *ip1 = du1->ip;
struct xfs_inode *dp2 = du2->dp;
const struct xfs_name *name2 = du2->name;
struct xfs_inode *ip2 = du2->ip;
int ip1_flags = 0;
int ip2_flags = 0;
int dp2_flags = 0;
int error;
/* Swap inode number for dirent in first parent */
error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres);
if (error)
return error;
/* Swap inode number for dirent in second parent */
error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres);
if (error)
return error;
/*
* If we're renaming one or more directories across different parents,
* update the respective ".." entries (and link counts) to match the new
* parents.
*/
if (dp1 != dp2) {
dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
if (S_ISDIR(VFS_I(ip2)->i_mode)) {
error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
dp1->i_ino, spaceres);
if (error)
return error;
/* transfer ip2 ".." reference to dp1 */
if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
error = xfs_droplink(tp, dp2);
if (error)
return error;
xfs_bumplink(tp, dp1);
}
/*
* Although ip1 isn't changed here, userspace needs
* to be warned about the change, so that applications
* relying on it (like backup ones), will properly
* notify the change
*/
ip1_flags |= XFS_ICHGTIME_CHG;
ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
}
if (S_ISDIR(VFS_I(ip1)->i_mode)) {
error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
dp2->i_ino, spaceres);
if (error)
return error;
/* transfer ip1 ".." reference to dp2 */
if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
error = xfs_droplink(tp, dp1);
if (error)
return error;
xfs_bumplink(tp, dp2);
}
/*
* Although ip2 isn't changed here, userspace needs
* to be warned about the change, so that applications
* relying on it (like backup ones), will properly
* notify the change
*/
ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
ip2_flags |= XFS_ICHGTIME_CHG;
}
}
if (ip1_flags) {
xfs_trans_ichgtime(tp, ip1, ip1_flags);
xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
}
if (ip2_flags) {
xfs_trans_ichgtime(tp, ip2, ip2_flags);
xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
}
if (dp2_flags) {
xfs_trans_ichgtime(tp, dp2, dp2_flags);
xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
}
xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
/* Schedule parent pointer replacements */
if (du1->ppargs) {
error = xfs_parent_replacename(tp, du1->ppargs, dp1, name1,
dp2, name2, ip1);
if (error)
return error;
}
if (du2->ppargs) {
error = xfs_parent_replacename(tp, du2->ppargs, dp2, name2,
dp1, name1, ip2);
if (error)
return error;
}
/*
* Inform our hook clients that we've finished an exchange operation as
* follows: removed the source and target files from their directories;
* added the target to the source directory; and added the source to
* the target directory. All inodes are locked, so it's ok to model a
* rename this way so long as we say we deleted entries before we add
* new ones.
*/
xfs_dir_update_hook(dp1, ip1, -1, name1);
xfs_dir_update_hook(dp2, ip2, -1, name2);
xfs_dir_update_hook(dp1, ip2, 1, name1);
xfs_dir_update_hook(dp2, ip1, 1, name2);
return 0;
}
/*
* Given an entry (@src_name, @src_ip) in directory @src_dp, make the entry
* @target_name in directory @target_dp point to @src_ip and remove the
* original entry, cleaning up everything left behind.
*
* Cleanup involves dropping a link count on @target_ip, and either removing
* the (@src_name, @src_ip) entry from @src_dp or simply replacing the entry
* with (@src_name, @wip) if a whiteout inode @wip is supplied.
*
* All inodes must have the ILOCK held. We assume that if @src_ip is a
* directory then its '..' doesn't already point to @target_dp, and that @wip
* is a freshly allocated whiteout.
*/
int
xfs_dir_rename_children(
struct xfs_trans *tp,
struct xfs_dir_update *du_src,
struct xfs_dir_update *du_tgt,
unsigned int spaceres,
struct xfs_dir_update *du_wip)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_inode *src_dp = du_src->dp;
const struct xfs_name *src_name = du_src->name;
struct xfs_inode *src_ip = du_src->ip;
struct xfs_inode *target_dp = du_tgt->dp;
const struct xfs_name *target_name = du_tgt->name;
struct xfs_inode *target_ip = du_tgt->ip;
bool new_parent = (src_dp != target_dp);
bool src_is_directory;
int error;
src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
/*
* Check for expected errors before we dirty the transaction
* so we can return an error without a transaction abort.
*/
if (target_ip == NULL) {
/*
* If there's no space reservation, check the entry will
* fit before actually inserting it.
*/
if (!spaceres) {
error = xfs_dir_canenter(tp, target_dp, target_name);
if (error)
return error;
}
} else {
/*
* If target exists and it's a directory, check that whether
* it can be destroyed.
*/
if (S_ISDIR(VFS_I(target_ip)->i_mode) &&
(!xfs_dir_isempty(target_ip) ||
(VFS_I(target_ip)->i_nlink > 2)))
return -EEXIST;
}
/*
* Directory entry creation below may acquire the AGF. Remove
* the whiteout from the unlinked list first to preserve correct
* AGI/AGF locking order. This dirties the transaction so failures
* after this point will abort and log recovery will clean up the
* mess.
*
* For whiteouts, we need to bump the link count on the whiteout
* inode. After this point, we have a real link, clear the tmpfile
* state flag from the inode so it doesn't accidentally get misused
* in future.
*/
if (du_wip->ip) {
struct xfs_perag *pag;
ASSERT(VFS_I(du_wip->ip)->i_nlink == 0);
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, du_wip->ip->i_ino));
error = xfs_iunlink_remove(tp, pag, du_wip->ip);
xfs_perag_put(pag);
if (error)
return error;
xfs_bumplink(tp, du_wip->ip);
}
/*
* Set up the target.
*/
if (target_ip == NULL) {
/*
* If target does not exist and the rename crosses
* directories, adjust the target directory link count
* to account for the ".." reference from the new entry.
*/
error = xfs_dir_createname(tp, target_dp, target_name,
src_ip->i_ino, spaceres);
if (error)
return error;
xfs_trans_ichgtime(tp, target_dp,
XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
if (new_parent && src_is_directory) {
xfs_bumplink(tp, target_dp);
}
} else { /* target_ip != NULL */
/*
* Link the source inode under the target name.
* If the source inode is a directory and we are moving
* it across directories, its ".." entry will be
* inconsistent until we replace that down below.
*
* In case there is already an entry with the same
* name at the destination directory, remove it first.
*/
error = xfs_dir_replace(tp, target_dp, target_name,
src_ip->i_ino, spaceres);
if (error)
return error;
xfs_trans_ichgtime(tp, target_dp,
XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
/*
* Decrement the link count on the target since the target
* dir no longer points to it.
*/
error = xfs_droplink(tp, target_ip);
if (error)
return error;
if (src_is_directory) {
/*
* Drop the link from the old "." entry.
*/
error = xfs_droplink(tp, target_ip);
if (error)
return error;
}
} /* target_ip != NULL */
/*
* Remove the source.
*/
if (new_parent && src_is_directory) {
/*
* Rewrite the ".." entry to point to the new
* directory.
*/
error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
target_dp->i_ino, spaceres);
ASSERT(error != -EEXIST);
if (error)
return error;
}
/*
* We always want to hit the ctime on the source inode.
*
* This isn't strictly required by the standards since the source
* inode isn't really being changed, but old unix file systems did
* it and some incremental backup programs won't work without it.
*/
xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
/*
* Adjust the link count on src_dp. This is necessary when
* renaming a directory, either within one parent when
* the target existed, or across two parent directories.
*/
if (src_is_directory && (new_parent || target_ip != NULL)) {
/*
* Decrement link count on src_directory since the
* entry that's moved no longer points to it.
*/
error = xfs_droplink(tp, src_dp);
if (error)
return error;
}
/*
* For whiteouts, we only need to update the source dirent with the
* inode number of the whiteout inode rather than removing it
* altogether.
*/
if (du_wip->ip)
error = xfs_dir_replace(tp, src_dp, src_name, du_wip->ip->i_ino,
spaceres);
else
error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
spaceres);
if (error)
return error;
xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
if (new_parent)
xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
/* Schedule parent pointer updates. */
if (du_wip->ppargs) {
error = xfs_parent_addname(tp, du_wip->ppargs, src_dp,
src_name, du_wip->ip);
if (error)
return error;
}
if (du_src->ppargs) {
error = xfs_parent_replacename(tp, du_src->ppargs, src_dp,
src_name, target_dp, target_name, src_ip);
if (error)
return error;
}
if (du_tgt->ppargs) {
error = xfs_parent_removename(tp, du_tgt->ppargs, target_dp,
target_name, target_ip);
if (error)
return error;
}
/*
* Inform our hook clients that we've finished a rename operation as
* follows: removed the source and target files from their directories;
* that we've added the source to the target directory; and finally
* that we've added the whiteout, if there was one. All inodes are
* locked, so it's ok to model a rename this way so long as we say we
* deleted entries before we add new ones.
*/
if (target_ip)
xfs_dir_update_hook(target_dp, target_ip, -1, target_name);
xfs_dir_update_hook(src_dp, src_ip, -1, src_name);
xfs_dir_update_hook(target_dp, src_ip, 1, target_name);
if (du_wip->ip)
xfs_dir_update_hook(src_dp, du_wip->ip, 1, src_name);
return 0;
}
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