linux/fs/xfs/libxfs/xfs_dir2_sf.c
Darrick J. Wong 6da1b4b1ab xfs: fix an ABBA deadlock in xfs_rename
When overlayfs is running on top of xfs and the user unlinks a file in
the overlay, overlayfs will create a whiteout inode and ask xfs to
"rename" the whiteout file atop the one being unlinked.  If the file
being unlinked loses its one nlink, we then have to put the inode on the
unlinked list.

This requires us to grab the AGI buffer of the whiteout inode to take it
off the unlinked list (which is where whiteouts are created) and to grab
the AGI buffer of the file being deleted.  If the whiteout was created
in a higher numbered AG than the file being deleted, we'll lock the AGIs
in the wrong order and deadlock.

Therefore, grab all the AGI locks we think we'll need ahead of time, and
in order of increasing AG number per the locking rules.

Reported-by: wenli xie <wlxie7296@gmail.com>
Fixes: 93597ae8da ("xfs: Fix deadlock between AGI and AGF when target_ip exists in xfs_rename()")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-01-22 16:54:43 -08:00

1298 lines
37 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2003,2005 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_dir2.h"
#include "xfs_dir2_priv.h"
#include "xfs_trace.h"
/*
* Prototypes for internal functions.
*/
static void xfs_dir2_sf_addname_easy(xfs_da_args_t *args,
xfs_dir2_sf_entry_t *sfep,
xfs_dir2_data_aoff_t offset,
int new_isize);
static void xfs_dir2_sf_addname_hard(xfs_da_args_t *args, int objchange,
int new_isize);
static int xfs_dir2_sf_addname_pick(xfs_da_args_t *args, int objchange,
xfs_dir2_sf_entry_t **sfepp,
xfs_dir2_data_aoff_t *offsetp);
#ifdef DEBUG
static void xfs_dir2_sf_check(xfs_da_args_t *args);
#else
#define xfs_dir2_sf_check(args)
#endif /* DEBUG */
static void xfs_dir2_sf_toino4(xfs_da_args_t *args);
static void xfs_dir2_sf_toino8(xfs_da_args_t *args);
int
xfs_dir2_sf_entsize(
struct xfs_mount *mp,
struct xfs_dir2_sf_hdr *hdr,
int len)
{
int count = len;
count += sizeof(struct xfs_dir2_sf_entry); /* namelen + offset */
count += hdr->i8count ? XFS_INO64_SIZE : XFS_INO32_SIZE; /* ino # */
if (xfs_sb_version_hasftype(&mp->m_sb))
count += sizeof(uint8_t);
return count;
}
struct xfs_dir2_sf_entry *
xfs_dir2_sf_nextentry(
struct xfs_mount *mp,
struct xfs_dir2_sf_hdr *hdr,
struct xfs_dir2_sf_entry *sfep)
{
return (void *)sfep + xfs_dir2_sf_entsize(mp, hdr, sfep->namelen);
}
/*
* In short-form directory entries the inode numbers are stored at variable
* offset behind the entry name. If the entry stores a filetype value, then it
* sits between the name and the inode number. The actual inode numbers can
* come in two formats as well, either 4 bytes or 8 bytes wide.
*/
xfs_ino_t
xfs_dir2_sf_get_ino(
struct xfs_mount *mp,
struct xfs_dir2_sf_hdr *hdr,
struct xfs_dir2_sf_entry *sfep)
{
uint8_t *from = sfep->name + sfep->namelen;
if (xfs_sb_version_hasftype(&mp->m_sb))
from++;
if (!hdr->i8count)
return get_unaligned_be32(from);
return get_unaligned_be64(from) & XFS_MAXINUMBER;
}
void
xfs_dir2_sf_put_ino(
struct xfs_mount *mp,
struct xfs_dir2_sf_hdr *hdr,
struct xfs_dir2_sf_entry *sfep,
xfs_ino_t ino)
{
uint8_t *to = sfep->name + sfep->namelen;
ASSERT(ino <= XFS_MAXINUMBER);
if (xfs_sb_version_hasftype(&mp->m_sb))
to++;
if (hdr->i8count)
put_unaligned_be64(ino, to);
else
put_unaligned_be32(ino, to);
}
xfs_ino_t
xfs_dir2_sf_get_parent_ino(
struct xfs_dir2_sf_hdr *hdr)
{
if (!hdr->i8count)
return get_unaligned_be32(hdr->parent);
return get_unaligned_be64(hdr->parent) & XFS_MAXINUMBER;
}
void
xfs_dir2_sf_put_parent_ino(
struct xfs_dir2_sf_hdr *hdr,
xfs_ino_t ino)
{
ASSERT(ino <= XFS_MAXINUMBER);
if (hdr->i8count)
put_unaligned_be64(ino, hdr->parent);
else
put_unaligned_be32(ino, hdr->parent);
}
/*
* The file type field is stored at the end of the name for filetype enabled
* shortform directories, or not at all otherwise.
*/
uint8_t
xfs_dir2_sf_get_ftype(
struct xfs_mount *mp,
struct xfs_dir2_sf_entry *sfep)
{
if (xfs_sb_version_hasftype(&mp->m_sb)) {
uint8_t ftype = sfep->name[sfep->namelen];
if (ftype < XFS_DIR3_FT_MAX)
return ftype;
}
return XFS_DIR3_FT_UNKNOWN;
}
void
xfs_dir2_sf_put_ftype(
struct xfs_mount *mp,
struct xfs_dir2_sf_entry *sfep,
uint8_t ftype)
{
ASSERT(ftype < XFS_DIR3_FT_MAX);
if (xfs_sb_version_hasftype(&mp->m_sb))
sfep->name[sfep->namelen] = ftype;
}
/*
* Given a block directory (dp/block), calculate its size as a shortform (sf)
* directory and a header for the sf directory, if it will fit it the
* space currently present in the inode. If it won't fit, the output
* size is too big (but not accurate).
*/
int /* size for sf form */
xfs_dir2_block_sfsize(
xfs_inode_t *dp, /* incore inode pointer */
xfs_dir2_data_hdr_t *hdr, /* block directory data */
xfs_dir2_sf_hdr_t *sfhp) /* output: header for sf form */
{
xfs_dir2_dataptr_t addr; /* data entry address */
xfs_dir2_leaf_entry_t *blp; /* leaf area of the block */
xfs_dir2_block_tail_t *btp; /* tail area of the block */
int count; /* shortform entry count */
xfs_dir2_data_entry_t *dep; /* data entry in the block */
int i; /* block entry index */
int i8count; /* count of big-inode entries */
int isdot; /* entry is "." */
int isdotdot; /* entry is ".." */
xfs_mount_t *mp; /* mount structure pointer */
int namelen; /* total name bytes */
xfs_ino_t parent = 0; /* parent inode number */
int size=0; /* total computed size */
int has_ftype;
struct xfs_da_geometry *geo;
mp = dp->i_mount;
geo = mp->m_dir_geo;
/*
* if there is a filetype field, add the extra byte to the namelen
* for each entry that we see.
*/
has_ftype = xfs_sb_version_hasftype(&mp->m_sb) ? 1 : 0;
count = i8count = namelen = 0;
btp = xfs_dir2_block_tail_p(geo, hdr);
blp = xfs_dir2_block_leaf_p(btp);
/*
* Iterate over the block's data entries by using the leaf pointers.
*/
for (i = 0; i < be32_to_cpu(btp->count); i++) {
if ((addr = be32_to_cpu(blp[i].address)) == XFS_DIR2_NULL_DATAPTR)
continue;
/*
* Calculate the pointer to the entry at hand.
*/
dep = (xfs_dir2_data_entry_t *)((char *)hdr +
xfs_dir2_dataptr_to_off(geo, addr));
/*
* Detect . and .., so we can special-case them.
* . is not included in sf directories.
* .. is included by just the parent inode number.
*/
isdot = dep->namelen == 1 && dep->name[0] == '.';
isdotdot =
dep->namelen == 2 &&
dep->name[0] == '.' && dep->name[1] == '.';
if (!isdot)
i8count += be64_to_cpu(dep->inumber) > XFS_DIR2_MAX_SHORT_INUM;
/* take into account the file type field */
if (!isdot && !isdotdot) {
count++;
namelen += dep->namelen + has_ftype;
} else if (isdotdot)
parent = be64_to_cpu(dep->inumber);
/*
* Calculate the new size, see if we should give up yet.
*/
size = xfs_dir2_sf_hdr_size(i8count) + /* header */
count * 3 * sizeof(u8) + /* namelen + offset */
namelen + /* name */
(i8count ? /* inumber */
count * XFS_INO64_SIZE :
count * XFS_INO32_SIZE);
if (size > XFS_IFORK_DSIZE(dp))
return size; /* size value is a failure */
}
/*
* Create the output header, if it worked.
*/
sfhp->count = count;
sfhp->i8count = i8count;
xfs_dir2_sf_put_parent_ino(sfhp, parent);
return size;
}
/*
* Convert a block format directory to shortform.
* Caller has already checked that it will fit, and built us a header.
*/
int /* error */
xfs_dir2_block_to_sf(
struct xfs_da_args *args, /* operation arguments */
struct xfs_buf *bp,
int size, /* shortform directory size */
struct xfs_dir2_sf_hdr *sfhp) /* shortform directory hdr */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
int error; /* error return value */
int logflags; /* inode logging flags */
struct xfs_dir2_sf_entry *sfep; /* shortform entry */
struct xfs_dir2_sf_hdr *sfp; /* shortform directory header */
unsigned int offset = args->geo->data_entry_offset;
unsigned int end;
trace_xfs_dir2_block_to_sf(args);
/*
* Allocate a temporary destination buffer the size of the inode to
* format the data into. Once we have formatted the data, we can free
* the block and copy the formatted data into the inode literal area.
*/
sfp = kmem_alloc(mp->m_sb.sb_inodesize, 0);
memcpy(sfp, sfhp, xfs_dir2_sf_hdr_size(sfhp->i8count));
/*
* Loop over the active and unused entries. Stop when we reach the
* leaf/tail portion of the block.
*/
end = xfs_dir3_data_end_offset(args->geo, bp->b_addr);
sfep = xfs_dir2_sf_firstentry(sfp);
while (offset < end) {
struct xfs_dir2_data_unused *dup = bp->b_addr + offset;
struct xfs_dir2_data_entry *dep = bp->b_addr + offset;
/*
* If it's unused, just skip over it.
*/
if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
offset += be16_to_cpu(dup->length);
continue;
}
/*
* Skip .
*/
if (dep->namelen == 1 && dep->name[0] == '.')
ASSERT(be64_to_cpu(dep->inumber) == dp->i_ino);
/*
* Skip .., but make sure the inode number is right.
*/
else if (dep->namelen == 2 &&
dep->name[0] == '.' && dep->name[1] == '.')
ASSERT(be64_to_cpu(dep->inumber) ==
xfs_dir2_sf_get_parent_ino(sfp));
/*
* Normal entry, copy it into shortform.
*/
else {
sfep->namelen = dep->namelen;
xfs_dir2_sf_put_offset(sfep, offset);
memcpy(sfep->name, dep->name, dep->namelen);
xfs_dir2_sf_put_ino(mp, sfp, sfep,
be64_to_cpu(dep->inumber));
xfs_dir2_sf_put_ftype(mp, sfep,
xfs_dir2_data_get_ftype(mp, dep));
sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep);
}
offset += xfs_dir2_data_entsize(mp, dep->namelen);
}
ASSERT((char *)sfep - (char *)sfp == size);
/* now we are done with the block, we can shrink the inode */
logflags = XFS_ILOG_CORE;
error = xfs_dir2_shrink_inode(args, args->geo->datablk, bp);
if (error) {
ASSERT(error != -ENOSPC);
goto out;
}
/*
* The buffer is now unconditionally gone, whether
* xfs_dir2_shrink_inode worked or not.
*
* Convert the inode to local format and copy the data in.
*/
ASSERT(dp->i_df.if_bytes == 0);
xfs_init_local_fork(dp, XFS_DATA_FORK, sfp, size);
dp->i_df.if_format = XFS_DINODE_FMT_LOCAL;
dp->i_d.di_size = size;
logflags |= XFS_ILOG_DDATA;
xfs_dir2_sf_check(args);
out:
xfs_trans_log_inode(args->trans, dp, logflags);
kmem_free(sfp);
return error;
}
/*
* Add a name to a shortform directory.
* There are two algorithms, "easy" and "hard" which we decide on
* before changing anything.
* Convert to block form if necessary, if the new entry won't fit.
*/
int /* error */
xfs_dir2_sf_addname(
xfs_da_args_t *args) /* operation arguments */
{
xfs_inode_t *dp; /* incore directory inode */
int error; /* error return value */
int incr_isize; /* total change in size */
int new_isize; /* di_size after adding name */
int objchange; /* changing to 8-byte inodes */
xfs_dir2_data_aoff_t offset = 0; /* offset for new entry */
int pick; /* which algorithm to use */
xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
xfs_dir2_sf_entry_t *sfep = NULL; /* shortform entry */
trace_xfs_dir2_sf_addname(args);
ASSERT(xfs_dir2_sf_lookup(args) == -ENOENT);
dp = args->dp;
ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
ASSERT(dp->i_d.di_size >= offsetof(struct xfs_dir2_sf_hdr, parent));
ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
ASSERT(dp->i_df.if_u1.if_data != NULL);
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->i8count));
/*
* Compute entry (and change in) size.
*/
incr_isize = xfs_dir2_sf_entsize(dp->i_mount, sfp, args->namelen);
objchange = 0;
/*
* Do we have to change to 8 byte inodes?
*/
if (args->inumber > XFS_DIR2_MAX_SHORT_INUM && sfp->i8count == 0) {
/*
* Yes, adjust the inode size. old count + (parent + new)
*/
incr_isize += (sfp->count + 2) * XFS_INO64_DIFF;
objchange = 1;
}
new_isize = (int)dp->i_d.di_size + incr_isize;
/*
* Won't fit as shortform any more (due to size),
* or the pick routine says it won't (due to offset values).
*/
if (new_isize > XFS_IFORK_DSIZE(dp) ||
(pick =
xfs_dir2_sf_addname_pick(args, objchange, &sfep, &offset)) == 0) {
/*
* Just checking or no space reservation, it doesn't fit.
*/
if ((args->op_flags & XFS_DA_OP_JUSTCHECK) || args->total == 0)
return -ENOSPC;
/*
* Convert to block form then add the name.
*/
error = xfs_dir2_sf_to_block(args);
if (error)
return error;
return xfs_dir2_block_addname(args);
}
/*
* Just checking, it fits.
*/
if (args->op_flags & XFS_DA_OP_JUSTCHECK)
return 0;
/*
* Do it the easy way - just add it at the end.
*/
if (pick == 1)
xfs_dir2_sf_addname_easy(args, sfep, offset, new_isize);
/*
* Do it the hard way - look for a place to insert the new entry.
* Convert to 8 byte inode numbers first if necessary.
*/
else {
ASSERT(pick == 2);
if (objchange)
xfs_dir2_sf_toino8(args);
xfs_dir2_sf_addname_hard(args, objchange, new_isize);
}
xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_DDATA);
return 0;
}
/*
* Add the new entry the "easy" way.
* This is copying the old directory and adding the new entry at the end.
* Since it's sorted by "offset" we need room after the last offset
* that's already there, and then room to convert to a block directory.
* This is already checked by the pick routine.
*/
static void
xfs_dir2_sf_addname_easy(
xfs_da_args_t *args, /* operation arguments */
xfs_dir2_sf_entry_t *sfep, /* pointer to new entry */
xfs_dir2_data_aoff_t offset, /* offset to use for new ent */
int new_isize) /* new directory size */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
int byteoff; /* byte offset in sf dir */
xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
byteoff = (int)((char *)sfep - (char *)sfp);
/*
* Grow the in-inode space.
*/
xfs_idata_realloc(dp, xfs_dir2_sf_entsize(mp, sfp, args->namelen),
XFS_DATA_FORK);
/*
* Need to set up again due to realloc of the inode data.
*/
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
sfep = (xfs_dir2_sf_entry_t *)((char *)sfp + byteoff);
/*
* Fill in the new entry.
*/
sfep->namelen = args->namelen;
xfs_dir2_sf_put_offset(sfep, offset);
memcpy(sfep->name, args->name, sfep->namelen);
xfs_dir2_sf_put_ino(mp, sfp, sfep, args->inumber);
xfs_dir2_sf_put_ftype(mp, sfep, args->filetype);
/*
* Update the header and inode.
*/
sfp->count++;
if (args->inumber > XFS_DIR2_MAX_SHORT_INUM)
sfp->i8count++;
dp->i_d.di_size = new_isize;
xfs_dir2_sf_check(args);
}
/*
* Add the new entry the "hard" way.
* The caller has already converted to 8 byte inode numbers if necessary,
* in which case we need to leave the i8count at 1.
* Find a hole that the new entry will fit into, and copy
* the first part of the entries, the new entry, and the last part of
* the entries.
*/
/* ARGSUSED */
static void
xfs_dir2_sf_addname_hard(
xfs_da_args_t *args, /* operation arguments */
int objchange, /* changing inode number size */
int new_isize) /* new directory size */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
int add_datasize; /* data size need for new ent */
char *buf; /* buffer for old */
int eof; /* reached end of old dir */
int nbytes; /* temp for byte copies */
xfs_dir2_data_aoff_t new_offset; /* next offset value */
xfs_dir2_data_aoff_t offset; /* current offset value */
int old_isize; /* previous di_size */
xfs_dir2_sf_entry_t *oldsfep; /* entry in original dir */
xfs_dir2_sf_hdr_t *oldsfp; /* original shortform dir */
xfs_dir2_sf_entry_t *sfep; /* entry in new dir */
xfs_dir2_sf_hdr_t *sfp; /* new shortform dir */
/*
* Copy the old directory to the stack buffer.
*/
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
old_isize = (int)dp->i_d.di_size;
buf = kmem_alloc(old_isize, 0);
oldsfp = (xfs_dir2_sf_hdr_t *)buf;
memcpy(oldsfp, sfp, old_isize);
/*
* Loop over the old directory finding the place we're going
* to insert the new entry.
* If it's going to end up at the end then oldsfep will point there.
*/
for (offset = args->geo->data_first_offset,
oldsfep = xfs_dir2_sf_firstentry(oldsfp),
add_datasize = xfs_dir2_data_entsize(mp, args->namelen),
eof = (char *)oldsfep == &buf[old_isize];
!eof;
offset = new_offset + xfs_dir2_data_entsize(mp, oldsfep->namelen),
oldsfep = xfs_dir2_sf_nextentry(mp, oldsfp, oldsfep),
eof = (char *)oldsfep == &buf[old_isize]) {
new_offset = xfs_dir2_sf_get_offset(oldsfep);
if (offset + add_datasize <= new_offset)
break;
}
/*
* Get rid of the old directory, then allocate space for
* the new one. We do this so xfs_idata_realloc won't copy
* the data.
*/
xfs_idata_realloc(dp, -old_isize, XFS_DATA_FORK);
xfs_idata_realloc(dp, new_isize, XFS_DATA_FORK);
/*
* Reset the pointer since the buffer was reallocated.
*/
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
/*
* Copy the first part of the directory, including the header.
*/
nbytes = (int)((char *)oldsfep - (char *)oldsfp);
memcpy(sfp, oldsfp, nbytes);
sfep = (xfs_dir2_sf_entry_t *)((char *)sfp + nbytes);
/*
* Fill in the new entry, and update the header counts.
*/
sfep->namelen = args->namelen;
xfs_dir2_sf_put_offset(sfep, offset);
memcpy(sfep->name, args->name, sfep->namelen);
xfs_dir2_sf_put_ino(mp, sfp, sfep, args->inumber);
xfs_dir2_sf_put_ftype(mp, sfep, args->filetype);
sfp->count++;
if (args->inumber > XFS_DIR2_MAX_SHORT_INUM && !objchange)
sfp->i8count++;
/*
* If there's more left to copy, do that.
*/
if (!eof) {
sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep);
memcpy(sfep, oldsfep, old_isize - nbytes);
}
kmem_free(buf);
dp->i_d.di_size = new_isize;
xfs_dir2_sf_check(args);
}
/*
* Decide if the new entry will fit at all.
* If it will fit, pick between adding the new entry to the end (easy)
* or somewhere else (hard).
* Return 0 (won't fit), 1 (easy), 2 (hard).
*/
/*ARGSUSED*/
static int /* pick result */
xfs_dir2_sf_addname_pick(
xfs_da_args_t *args, /* operation arguments */
int objchange, /* inode # size changes */
xfs_dir2_sf_entry_t **sfepp, /* out(1): new entry ptr */
xfs_dir2_data_aoff_t *offsetp) /* out(1): new offset */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
int holefit; /* found hole it will fit in */
int i; /* entry number */
xfs_dir2_data_aoff_t offset; /* data block offset */
xfs_dir2_sf_entry_t *sfep; /* shortform entry */
xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
int size; /* entry's data size */
int used; /* data bytes used */
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
size = xfs_dir2_data_entsize(mp, args->namelen);
offset = args->geo->data_first_offset;
sfep = xfs_dir2_sf_firstentry(sfp);
holefit = 0;
/*
* Loop over sf entries.
* Keep track of data offset and whether we've seen a place
* to insert the new entry.
*/
for (i = 0; i < sfp->count; i++) {
if (!holefit)
holefit = offset + size <= xfs_dir2_sf_get_offset(sfep);
offset = xfs_dir2_sf_get_offset(sfep) +
xfs_dir2_data_entsize(mp, sfep->namelen);
sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep);
}
/*
* Calculate data bytes used excluding the new entry, if this
* was a data block (block form directory).
*/
used = offset +
(sfp->count + 3) * (uint)sizeof(xfs_dir2_leaf_entry_t) +
(uint)sizeof(xfs_dir2_block_tail_t);
/*
* If it won't fit in a block form then we can't insert it,
* we'll go back, convert to block, then try the insert and convert
* to leaf.
*/
if (used + (holefit ? 0 : size) > args->geo->blksize)
return 0;
/*
* If changing the inode number size, do it the hard way.
*/
if (objchange)
return 2;
/*
* If it won't fit at the end then do it the hard way (use the hole).
*/
if (used + size > args->geo->blksize)
return 2;
/*
* Do it the easy way.
*/
*sfepp = sfep;
*offsetp = offset;
return 1;
}
#ifdef DEBUG
/*
* Check consistency of shortform directory, assert if bad.
*/
static void
xfs_dir2_sf_check(
xfs_da_args_t *args) /* operation arguments */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
int i; /* entry number */
int i8count; /* number of big inode#s */
xfs_ino_t ino; /* entry inode number */
int offset; /* data offset */
xfs_dir2_sf_entry_t *sfep; /* shortform dir entry */
xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
offset = args->geo->data_first_offset;
ino = xfs_dir2_sf_get_parent_ino(sfp);
i8count = ino > XFS_DIR2_MAX_SHORT_INUM;
for (i = 0, sfep = xfs_dir2_sf_firstentry(sfp);
i < sfp->count;
i++, sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep)) {
ASSERT(xfs_dir2_sf_get_offset(sfep) >= offset);
ino = xfs_dir2_sf_get_ino(mp, sfp, sfep);
i8count += ino > XFS_DIR2_MAX_SHORT_INUM;
offset =
xfs_dir2_sf_get_offset(sfep) +
xfs_dir2_data_entsize(mp, sfep->namelen);
ASSERT(xfs_dir2_sf_get_ftype(mp, sfep) < XFS_DIR3_FT_MAX);
}
ASSERT(i8count == sfp->i8count);
ASSERT((char *)sfep - (char *)sfp == dp->i_d.di_size);
ASSERT(offset +
(sfp->count + 2) * (uint)sizeof(xfs_dir2_leaf_entry_t) +
(uint)sizeof(xfs_dir2_block_tail_t) <= args->geo->blksize);
}
#endif /* DEBUG */
/* Verify the consistency of an inline directory. */
xfs_failaddr_t
xfs_dir2_sf_verify(
struct xfs_inode *ip)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
struct xfs_dir2_sf_hdr *sfp;
struct xfs_dir2_sf_entry *sfep;
struct xfs_dir2_sf_entry *next_sfep;
char *endp;
xfs_ino_t ino;
int i;
int i8count;
int offset;
int64_t size;
int error;
uint8_t filetype;
ASSERT(ifp->if_format == XFS_DINODE_FMT_LOCAL);
sfp = (struct xfs_dir2_sf_hdr *)ifp->if_u1.if_data;
size = ifp->if_bytes;
/*
* Give up if the directory is way too short.
*/
if (size <= offsetof(struct xfs_dir2_sf_hdr, parent) ||
size < xfs_dir2_sf_hdr_size(sfp->i8count))
return __this_address;
endp = (char *)sfp + size;
/* Check .. entry */
ino = xfs_dir2_sf_get_parent_ino(sfp);
i8count = ino > XFS_DIR2_MAX_SHORT_INUM;
error = xfs_dir_ino_validate(mp, ino);
if (error)
return __this_address;
offset = mp->m_dir_geo->data_first_offset;
/* Check all reported entries */
sfep = xfs_dir2_sf_firstentry(sfp);
for (i = 0; i < sfp->count; i++) {
/*
* struct xfs_dir2_sf_entry has a variable length.
* Check the fixed-offset parts of the structure are
* within the data buffer.
*/
if (((char *)sfep + sizeof(*sfep)) >= endp)
return __this_address;
/* Don't allow names with known bad length. */
if (sfep->namelen == 0)
return __this_address;
/*
* Check that the variable-length part of the structure is
* within the data buffer. The next entry starts after the
* name component, so nextentry is an acceptable test.
*/
next_sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep);
if (endp < (char *)next_sfep)
return __this_address;
/* Check that the offsets always increase. */
if (xfs_dir2_sf_get_offset(sfep) < offset)
return __this_address;
/* Check the inode number. */
ino = xfs_dir2_sf_get_ino(mp, sfp, sfep);
i8count += ino > XFS_DIR2_MAX_SHORT_INUM;
error = xfs_dir_ino_validate(mp, ino);
if (error)
return __this_address;
/* Check the file type. */
filetype = xfs_dir2_sf_get_ftype(mp, sfep);
if (filetype >= XFS_DIR3_FT_MAX)
return __this_address;
offset = xfs_dir2_sf_get_offset(sfep) +
xfs_dir2_data_entsize(mp, sfep->namelen);
sfep = next_sfep;
}
if (i8count != sfp->i8count)
return __this_address;
if ((void *)sfep != (void *)endp)
return __this_address;
/* Make sure this whole thing ought to be in local format. */
if (offset + (sfp->count + 2) * (uint)sizeof(xfs_dir2_leaf_entry_t) +
(uint)sizeof(xfs_dir2_block_tail_t) > mp->m_dir_geo->blksize)
return __this_address;
return NULL;
}
/*
* Create a new (shortform) directory.
*/
int /* error, always 0 */
xfs_dir2_sf_create(
xfs_da_args_t *args, /* operation arguments */
xfs_ino_t pino) /* parent inode number */
{
xfs_inode_t *dp; /* incore directory inode */
int i8count; /* parent inode is an 8-byte number */
xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
int size; /* directory size */
trace_xfs_dir2_sf_create(args);
dp = args->dp;
ASSERT(dp != NULL);
ASSERT(dp->i_d.di_size == 0);
/*
* If it's currently a zero-length extent file,
* convert it to local format.
*/
if (dp->i_df.if_format == XFS_DINODE_FMT_EXTENTS) {
dp->i_df.if_flags &= ~XFS_IFEXTENTS; /* just in case */
dp->i_df.if_format = XFS_DINODE_FMT_LOCAL;
xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE);
dp->i_df.if_flags |= XFS_IFINLINE;
}
ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
ASSERT(dp->i_df.if_bytes == 0);
i8count = pino > XFS_DIR2_MAX_SHORT_INUM;
size = xfs_dir2_sf_hdr_size(i8count);
/*
* Make a buffer for the data.
*/
xfs_idata_realloc(dp, size, XFS_DATA_FORK);
/*
* Fill in the header,
*/
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
sfp->i8count = i8count;
/*
* Now can put in the inode number, since i8count is set.
*/
xfs_dir2_sf_put_parent_ino(sfp, pino);
sfp->count = 0;
dp->i_d.di_size = size;
xfs_dir2_sf_check(args);
xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_DDATA);
return 0;
}
/*
* Lookup an entry in a shortform directory.
* Returns EEXIST if found, ENOENT if not found.
*/
int /* error */
xfs_dir2_sf_lookup(
xfs_da_args_t *args) /* operation arguments */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
int i; /* entry index */
int error;
xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */
xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
enum xfs_dacmp cmp; /* comparison result */
xfs_dir2_sf_entry_t *ci_sfep; /* case-insens. entry */
trace_xfs_dir2_sf_lookup(args);
xfs_dir2_sf_check(args);
ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
ASSERT(dp->i_d.di_size >= offsetof(struct xfs_dir2_sf_hdr, parent));
ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
ASSERT(dp->i_df.if_u1.if_data != NULL);
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->i8count));
/*
* Special case for .
*/
if (args->namelen == 1 && args->name[0] == '.') {
args->inumber = dp->i_ino;
args->cmpresult = XFS_CMP_EXACT;
args->filetype = XFS_DIR3_FT_DIR;
return -EEXIST;
}
/*
* Special case for ..
*/
if (args->namelen == 2 &&
args->name[0] == '.' && args->name[1] == '.') {
args->inumber = xfs_dir2_sf_get_parent_ino(sfp);
args->cmpresult = XFS_CMP_EXACT;
args->filetype = XFS_DIR3_FT_DIR;
return -EEXIST;
}
/*
* Loop over all the entries trying to match ours.
*/
ci_sfep = NULL;
for (i = 0, sfep = xfs_dir2_sf_firstentry(sfp); i < sfp->count;
i++, sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep)) {
/*
* Compare name and if it's an exact match, return the inode
* number. If it's the first case-insensitive match, store the
* inode number and continue looking for an exact match.
*/
cmp = xfs_dir2_compname(args, sfep->name, sfep->namelen);
if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
args->cmpresult = cmp;
args->inumber = xfs_dir2_sf_get_ino(mp, sfp, sfep);
args->filetype = xfs_dir2_sf_get_ftype(mp, sfep);
if (cmp == XFS_CMP_EXACT)
return -EEXIST;
ci_sfep = sfep;
}
}
ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
/*
* Here, we can only be doing a lookup (not a rename or replace).
* If a case-insensitive match was not found, return -ENOENT.
*/
if (!ci_sfep)
return -ENOENT;
/* otherwise process the CI match as required by the caller */
error = xfs_dir_cilookup_result(args, ci_sfep->name, ci_sfep->namelen);
return error;
}
/*
* Remove an entry from a shortform directory.
*/
int /* error */
xfs_dir2_sf_removename(
xfs_da_args_t *args)
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
int byteoff; /* offset of removed entry */
int entsize; /* this entry's size */
int i; /* shortform entry index */
int newsize; /* new inode size */
int oldsize; /* old inode size */
xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */
xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
trace_xfs_dir2_sf_removename(args);
ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
oldsize = (int)dp->i_d.di_size;
ASSERT(oldsize >= offsetof(struct xfs_dir2_sf_hdr, parent));
ASSERT(dp->i_df.if_bytes == oldsize);
ASSERT(dp->i_df.if_u1.if_data != NULL);
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
ASSERT(oldsize >= xfs_dir2_sf_hdr_size(sfp->i8count));
/*
* Loop over the old directory entries.
* Find the one we're deleting.
*/
for (i = 0, sfep = xfs_dir2_sf_firstentry(sfp); i < sfp->count;
i++, sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep)) {
if (xfs_da_compname(args, sfep->name, sfep->namelen) ==
XFS_CMP_EXACT) {
ASSERT(xfs_dir2_sf_get_ino(mp, sfp, sfep) ==
args->inumber);
break;
}
}
/*
* Didn't find it.
*/
if (i == sfp->count)
return -ENOENT;
/*
* Calculate sizes.
*/
byteoff = (int)((char *)sfep - (char *)sfp);
entsize = xfs_dir2_sf_entsize(mp, sfp, args->namelen);
newsize = oldsize - entsize;
/*
* Copy the part if any after the removed entry, sliding it down.
*/
if (byteoff + entsize < oldsize)
memmove((char *)sfp + byteoff, (char *)sfp + byteoff + entsize,
oldsize - (byteoff + entsize));
/*
* Fix up the header and file size.
*/
sfp->count--;
dp->i_d.di_size = newsize;
/*
* Reallocate, making it smaller.
*/
xfs_idata_realloc(dp, newsize - oldsize, XFS_DATA_FORK);
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
/*
* Are we changing inode number size?
*/
if (args->inumber > XFS_DIR2_MAX_SHORT_INUM) {
if (sfp->i8count == 1)
xfs_dir2_sf_toino4(args);
else
sfp->i8count--;
}
xfs_dir2_sf_check(args);
xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_DDATA);
return 0;
}
/*
* Check whether the sf dir replace operation need more blocks.
*/
static bool
xfs_dir2_sf_replace_needblock(
struct xfs_inode *dp,
xfs_ino_t inum)
{
int newsize;
struct xfs_dir2_sf_hdr *sfp;
if (dp->i_df.if_format != XFS_DINODE_FMT_LOCAL)
return false;
sfp = (struct xfs_dir2_sf_hdr *)dp->i_df.if_u1.if_data;
newsize = dp->i_df.if_bytes + (sfp->count + 1) * XFS_INO64_DIFF;
return inum > XFS_DIR2_MAX_SHORT_INUM &&
sfp->i8count == 0 && newsize > XFS_IFORK_DSIZE(dp);
}
/*
* Replace the inode number of an entry in a shortform directory.
*/
int /* error */
xfs_dir2_sf_replace(
xfs_da_args_t *args) /* operation arguments */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
int i; /* entry index */
xfs_ino_t ino=0; /* entry old inode number */
int i8elevated; /* sf_toino8 set i8count=1 */
xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */
xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
trace_xfs_dir2_sf_replace(args);
ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
ASSERT(dp->i_d.di_size >= offsetof(struct xfs_dir2_sf_hdr, parent));
ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
ASSERT(dp->i_df.if_u1.if_data != NULL);
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->i8count));
/*
* New inode number is large, and need to convert to 8-byte inodes.
*/
if (args->inumber > XFS_DIR2_MAX_SHORT_INUM && sfp->i8count == 0) {
int error; /* error return value */
/*
* Won't fit as shortform, convert to block then do replace.
*/
if (xfs_dir2_sf_replace_needblock(dp, args->inumber)) {
error = xfs_dir2_sf_to_block(args);
if (error)
return error;
return xfs_dir2_block_replace(args);
}
/*
* Still fits, convert to 8-byte now.
*/
xfs_dir2_sf_toino8(args);
i8elevated = 1;
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
} else
i8elevated = 0;
ASSERT(args->namelen != 1 || args->name[0] != '.');
/*
* Replace ..'s entry.
*/
if (args->namelen == 2 &&
args->name[0] == '.' && args->name[1] == '.') {
ino = xfs_dir2_sf_get_parent_ino(sfp);
ASSERT(args->inumber != ino);
xfs_dir2_sf_put_parent_ino(sfp, args->inumber);
}
/*
* Normal entry, look for the name.
*/
else {
for (i = 0, sfep = xfs_dir2_sf_firstentry(sfp); i < sfp->count;
i++, sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep)) {
if (xfs_da_compname(args, sfep->name, sfep->namelen) ==
XFS_CMP_EXACT) {
ino = xfs_dir2_sf_get_ino(mp, sfp, sfep);
ASSERT(args->inumber != ino);
xfs_dir2_sf_put_ino(mp, sfp, sfep,
args->inumber);
xfs_dir2_sf_put_ftype(mp, sfep, args->filetype);
break;
}
}
/*
* Didn't find it.
*/
if (i == sfp->count) {
ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
if (i8elevated)
xfs_dir2_sf_toino4(args);
return -ENOENT;
}
}
/*
* See if the old number was large, the new number is small.
*/
if (ino > XFS_DIR2_MAX_SHORT_INUM &&
args->inumber <= XFS_DIR2_MAX_SHORT_INUM) {
/*
* And the old count was one, so need to convert to small.
*/
if (sfp->i8count == 1)
xfs_dir2_sf_toino4(args);
else
sfp->i8count--;
}
/*
* See if the old number was small, the new number is large.
*/
if (ino <= XFS_DIR2_MAX_SHORT_INUM &&
args->inumber > XFS_DIR2_MAX_SHORT_INUM) {
/*
* add to the i8count unless we just converted to 8-byte
* inodes (which does an implied i8count = 1)
*/
ASSERT(sfp->i8count != 0);
if (!i8elevated)
sfp->i8count++;
}
xfs_dir2_sf_check(args);
xfs_trans_log_inode(args->trans, dp, XFS_ILOG_DDATA);
return 0;
}
/*
* Convert from 8-byte inode numbers to 4-byte inode numbers.
* The last 8-byte inode number is gone, but the count is still 1.
*/
static void
xfs_dir2_sf_toino4(
xfs_da_args_t *args) /* operation arguments */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
char *buf; /* old dir's buffer */
int i; /* entry index */
int newsize; /* new inode size */
xfs_dir2_sf_entry_t *oldsfep; /* old sf entry */
xfs_dir2_sf_hdr_t *oldsfp; /* old sf directory */
int oldsize; /* old inode size */
xfs_dir2_sf_entry_t *sfep; /* new sf entry */
xfs_dir2_sf_hdr_t *sfp; /* new sf directory */
trace_xfs_dir2_sf_toino4(args);
/*
* Copy the old directory to the buffer.
* Then nuke it from the inode, and add the new buffer to the inode.
* Don't want xfs_idata_realloc copying the data here.
*/
oldsize = dp->i_df.if_bytes;
buf = kmem_alloc(oldsize, 0);
oldsfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
ASSERT(oldsfp->i8count == 1);
memcpy(buf, oldsfp, oldsize);
/*
* Compute the new inode size.
*/
newsize = oldsize - (oldsfp->count + 1) * XFS_INO64_DIFF;
xfs_idata_realloc(dp, -oldsize, XFS_DATA_FORK);
xfs_idata_realloc(dp, newsize, XFS_DATA_FORK);
/*
* Reset our pointers, the data has moved.
*/
oldsfp = (xfs_dir2_sf_hdr_t *)buf;
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
/*
* Fill in the new header.
*/
sfp->count = oldsfp->count;
sfp->i8count = 0;
xfs_dir2_sf_put_parent_ino(sfp, xfs_dir2_sf_get_parent_ino(oldsfp));
/*
* Copy the entries field by field.
*/
for (i = 0, sfep = xfs_dir2_sf_firstentry(sfp),
oldsfep = xfs_dir2_sf_firstentry(oldsfp);
i < sfp->count;
i++, sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep),
oldsfep = xfs_dir2_sf_nextentry(mp, oldsfp, oldsfep)) {
sfep->namelen = oldsfep->namelen;
memcpy(sfep->offset, oldsfep->offset, sizeof(sfep->offset));
memcpy(sfep->name, oldsfep->name, sfep->namelen);
xfs_dir2_sf_put_ino(mp, sfp, sfep,
xfs_dir2_sf_get_ino(mp, oldsfp, oldsfep));
xfs_dir2_sf_put_ftype(mp, sfep,
xfs_dir2_sf_get_ftype(mp, oldsfep));
}
/*
* Clean up the inode.
*/
kmem_free(buf);
dp->i_d.di_size = newsize;
xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_DDATA);
}
/*
* Convert existing entries from 4-byte inode numbers to 8-byte inode numbers.
* The new entry w/ an 8-byte inode number is not there yet; we leave with
* i8count set to 1, but no corresponding 8-byte entry.
*/
static void
xfs_dir2_sf_toino8(
xfs_da_args_t *args) /* operation arguments */
{
struct xfs_inode *dp = args->dp;
struct xfs_mount *mp = dp->i_mount;
char *buf; /* old dir's buffer */
int i; /* entry index */
int newsize; /* new inode size */
xfs_dir2_sf_entry_t *oldsfep; /* old sf entry */
xfs_dir2_sf_hdr_t *oldsfp; /* old sf directory */
int oldsize; /* old inode size */
xfs_dir2_sf_entry_t *sfep; /* new sf entry */
xfs_dir2_sf_hdr_t *sfp; /* new sf directory */
trace_xfs_dir2_sf_toino8(args);
/*
* Copy the old directory to the buffer.
* Then nuke it from the inode, and add the new buffer to the inode.
* Don't want xfs_idata_realloc copying the data here.
*/
oldsize = dp->i_df.if_bytes;
buf = kmem_alloc(oldsize, 0);
oldsfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
ASSERT(oldsfp->i8count == 0);
memcpy(buf, oldsfp, oldsize);
/*
* Compute the new inode size (nb: entry count + 1 for parent)
*/
newsize = oldsize + (oldsfp->count + 1) * XFS_INO64_DIFF;
xfs_idata_realloc(dp, -oldsize, XFS_DATA_FORK);
xfs_idata_realloc(dp, newsize, XFS_DATA_FORK);
/*
* Reset our pointers, the data has moved.
*/
oldsfp = (xfs_dir2_sf_hdr_t *)buf;
sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
/*
* Fill in the new header.
*/
sfp->count = oldsfp->count;
sfp->i8count = 1;
xfs_dir2_sf_put_parent_ino(sfp, xfs_dir2_sf_get_parent_ino(oldsfp));
/*
* Copy the entries field by field.
*/
for (i = 0, sfep = xfs_dir2_sf_firstentry(sfp),
oldsfep = xfs_dir2_sf_firstentry(oldsfp);
i < sfp->count;
i++, sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep),
oldsfep = xfs_dir2_sf_nextentry(mp, oldsfp, oldsfep)) {
sfep->namelen = oldsfep->namelen;
memcpy(sfep->offset, oldsfep->offset, sizeof(sfep->offset));
memcpy(sfep->name, oldsfep->name, sfep->namelen);
xfs_dir2_sf_put_ino(mp, sfp, sfep,
xfs_dir2_sf_get_ino(mp, oldsfp, oldsfep));
xfs_dir2_sf_put_ftype(mp, sfep,
xfs_dir2_sf_get_ftype(mp, oldsfep));
}
/*
* Clean up the inode.
*/
kmem_free(buf);
dp->i_d.di_size = newsize;
xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_DDATA);
}