Commit Graph

51 Commits

Author SHA1 Message Date
Jianping Liu 3154060704 tkernel: sync code to the same with tk4 pub/lts/0017-kabi
Sync code to the same with tk4 pub/lts/0017-kabi, except deleted rue
and wujing. Partners can submit pull requests to this branch, and we
can pick the commits to tk4 pub/lts/0017-kabi easly.

Signed-off-by: Jianping Liu <frankjpliu@tencent.com>
2024-06-12 13:13:20 +08:00
Tetsuo Handa 707e0ddaf6 fs: xfs: Remove KM_NOSLEEP and KM_SLEEP.
Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP,
we can remove KM_NOSLEEP and replace KM_SLEEP with 0.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-08-26 12:06:22 -07:00
Darrick J. Wong 858b44dc62 xfs: remove more ondisk directory corruption asserts
Continue our game of replacing ASSERTs for corrupt ondisk metadata with
EFSCORRUPTED returns.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
2019-08-12 09:32:44 -07:00
Eric Sandeen 250d4b4c40 xfs: remove unused header files
There are many, many xfs header files which are included but
unneeded (or included twice) in the xfs code, so remove them.

nb: xfs_linux.h includes about 9 headers for everyone, so those
explicit includes get removed by this.  I'm not sure what the
preference is, but if we wanted explicit includes everywhere,
a followup patch could remove those xfs_*.h includes from
xfs_linux.h and move them into the files that need them.
Or it could be left as-is.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-28 19:30:43 -07:00
Christoph Hellwig dbd329f1e4 xfs: add struct xfs_mount pointer to struct xfs_buf
We need to derive the mount pointer from a buffer in a lot of place.
Add a direct pointer to short cut the pointer chasing.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-28 19:27:29 -07:00
Darrick J. Wong 15baadf72c xfs: fix xfs_buf magic number endian checks
Create a separate magic16 check function so that we don't run afoul of
static checkers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-02-18 09:38:41 -08:00
Brian Foster 8764f98351 xfs: factor xfs_da3_blkinfo verification into common helper
With the verifier magic value helper in place, we've left a bit more
duplicate code across the verifiers that involve struct
xfs_da3_blkinfo. This includes the da node, xattr leaf and dir leaf
verifiers, all of which perform similar checks for v4 and v5
filesystems.

Create a common helper to verify an xfs_da3_blkinfo structure,
taking care to only access v5 fields where appropriate, and refactor
the aforementioned verifiers to use the helper. No functional
changes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-02-11 16:07:01 -08:00
Brian Foster 39708c20ab xfs: miscellaneous verifier magic value fixups
Most buffer verifiers have hardcoded magic value checks
conditionalized on the version of the filesystem. The magic value
field of the verifier structure facilitates abstraction of some of
this code. Populate the ->magic field of various verifiers to take
advantage of this abstraction. No functional changes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-02-11 16:07:01 -08:00
Brian Foster e34d3e74eb xfs: always check magic values in on-disk byte order
Most verifiers that check on-disk magic values convert the CPU
endian magic value constant to disk endian to facilitate compile
time optimization of the byte swap and reduce the need for runtime
byte swaps in buffer verifiers. Several buffer verifiers do not
follow this pattern. Update those verifiers for consistency.

Also fix up a random typo in the inode readahead verifier name.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-02-11 16:07:01 -08:00
Darrick J. Wong 56830d6cc1 xfs: check da node magic in _node_lookup_int
Before we start processing what we /think/ is a da3 node block, actually
check the magic to make sure that we're looking at a node block.  This
way we won't blow the asserts in _node_hdr_from_disk on corrupted
metadata.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2018-08-01 07:42:43 -07:00
Darrick J. Wong 611995db2c xfs: use a local variable for magic number in xfs_da3_node_lookup_int
Use a local variable for the block magic number checks instead of
abusing blk->magic.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2018-08-01 07:42:18 -07:00
Brian Foster 2af5284253 xfs: remove xfs_bunmapi() firstblock param
All callers pass ->t_firstblock from the current transaction.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-11 22:26:25 -07:00
Brian Foster a7beabeae2 xfs: remove xfs_bmapi_write() firstblock param
All callers pass ->t_firstblock from the current transaction.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-11 22:26:25 -07:00
Brian Foster 766139032f xfs: use ->t_firstblock in xattr ops
Similar to the dirops code, the xattr code uses an on-stack
firstblock variable for the various operations. This code rolls the
underlying transaction in various places, however, which means we
cannot simply replace the local firstblock vars with ->t_firstblock.
Doing so (without further changes) would invalidate the memory
pointed to by xfs_da_args.firstblock as soon as the first
transaction rolls.

To avoid this problem, remove xfs_da_args.firstblock and replace all
such accesses with ->t_firstblock at the same time. This ensures
that accesses to the current firstblock always occur through the
current transaction rather than a potentially invalid xfs_da_args
pointer.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-11 22:26:22 -07:00
Brian Foster ccd9d91148 xfs: remove xfs_bunmapi() dfops param
Now that all xfs_bunmapi() callers use ->t_dfops, remove the
unnecessary parameter and access ->t_dfops directly. This patch does
not change behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-11 22:26:13 -07:00
Brian Foster 6e702a5dcb xfs: remove xfs_bmapi_write() dfops param
Now that all callers use ->t_dfops, the xfs_bmapi_write() dfops
parameter is no longer necessary. Remove it and access ->t_dfops
directly. This patch does not change behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-11 22:26:12 -07:00
Brian Foster 32a9b7c65c xfs: replace xfs_da_args->dfops accesses with ->t_dfops and remove
Now that xfs_da_args->dfops is always assigned from a ->t_dfops
pointer (or one that is immediately attached), replace all
downstream accesses of the former with the latter and remove the
field from struct xfs_da_args.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-11 22:26:11 -07:00
Dave Chinner 9bb54cb56a xfs: clean up MIN/MAX
Get rid of the MIN/MAX macros and just use the native min/max macros
directly in the XFS code.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-08 10:07:52 -07:00
Dave Chinner 0b61f8a407 xfs: convert to SPDX license tags
Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
	echo $f
	cat $f | awk -f hdr.awk > $f.new
	mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
	hdr = 1.0
	tag = "GPL-2.0"
	str = ""
}

/^ \* This program is free software/ {
	hdr = 2.0;
	next
}

/any later version./ {
	tag = "GPL-2.0+"
	next
}

/^ \*\// {
	if (hdr > 0.0) {
		print "// SPDX-License-Identifier: " tag
		print str
		print $0
		str=""
		hdr = 0.0
		next
	}
	print $0
	next
}

/^ \* / {
	if (hdr > 1.0)
		next
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
	next
}

/^ \*/ {
	if (hdr > 0.0)
		next
	print $0
	next
}

// {
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06 14:17:53 -07:00
Darrick J. Wong 2551a53053 xfs: explicitly pass buffer size to xfs_corruption_error
Explicitly pass the buffer length to xfs_corruption_error() instead of
assuming XFS_CORRUPTION_DUMP_LEN so that we avoid dumping off the end
of the buffer.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 18:25:05 -07:00
Darrick J. Wong 924cade4df xfs: don't return garbage buffers in xfs_da3_node_read
If we're reading a node in a dir/attr btree and the buffer comes off the
disk with a magic number we don't recognize, don't ASSERT and don't set
a garbage buffer type (0 also triggers ASSERTs).  Instead, report the
corruption, release the buffer, and return -EFSCORRUPTED because that's
what the dabtree is -- corrupt.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:30 -07:00
Carlos Maiolino fb1755a645 Split buffer's b_fspriv field
By splitting the b_fspriv field into two different fields (b_log_item
and b_li_list). It's possible to get rid of an old ABI workaround, by
using the new b_log_item field to store xfs_buf_log_item separated from
the log items attached to the buffer, which will be linked in the new
b_li_list field.

This way, there is no more need to reorder the log items list to place
the buf_log_item at the beginning of the list, simplifying a bit the
logic to handle buffer IO.

This also opens the possibility to change buffer's log items list into a
proper list_head.

b_log_item field is still defined as a void *, because it is still used
by the log buffers to store xlog_in_core structures, and there is no
need to add an extra field on xfs_buf just for xlog_in_core.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: minor style changes]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-01-29 07:27:22 -08:00
Darrick J. Wong b55725974c xfs: create a new buf_ops pointer to verify structure metadata
Expose all metadata structure buffer verifier functions via buf_ops.
These will be used by the online scrub mechanism to look for problems
with buffers that are already sitting around in memory.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-08 10:54:47 -08:00
Darrick J. Wong bc1a09b8e3 xfs: refactor verifier callers to print address of failing check
Refactor the callers of verifiers to print the instruction address of a
failing check.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-08 10:54:46 -08:00
Darrick J. Wong a6a781a58b xfs: have buffer verifier functions report failing address
Modify each function that checks the contents of a metadata buffer to
return the instruction address of the failing test so that we can report
more precise failure errors to the log.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-08 10:54:46 -08:00
Darrick J. Wong 31ca03c92c xfs: refactor xfs_verifier_error and xfs_buf_ioerror
Since all verification errors also mark the buffer as having an error,
we can combine these two calls.  Later we'll add a xfs_failaddr_t
parameter to promote the idea of reporting corruption errors and the
address of the failing check to enable better debugging reports.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-08 10:54:45 -08:00
Darrick J. Wong 8210f4dda2 xfs: abort dir/attr btree operation if btree is obviously weird
Abort an dir/attr btree operation if the attr btree has obvious problems
like loops back to the root or pointers don't point down the tree.
Found by fuzzing btree[0].before to zero in xfs/402, which livelocks on
the cycle in the attr btree.

Apply the same checks to xfs_da3_node_lookup_int.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-10-27 09:20:31 -07:00
Darrick J. Wong cd87d86792 xfs: don't crash on unexpected holes in dir/attr btrees
In quite a few places we call xfs_da_read_buf with a mappedbno that we
don't control, then assume that the function passes back either an error
code or a buffer pointer.  Unfortunately, if mappedbno == -2 and bno
maps to a hole, we get a return code of zero and a NULL buffer, which
means that we crash if we actually try to use that buffer pointer.  This
happens immediately when we set the buffer type for transaction context.

Therefore, check that we have no error code and a non-NULL bp before
trying to use bp.  This patch is a follow-up to an incomplete fix in
96a3aefb8f ("xfs: don't crash if reading a directory results in an
unexpected hole").

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-07-07 18:55:17 -07:00
Darrick J. Wong 8e8877e6ed xfs: return the hash value of a leaf1 directory block
Modify the existing dir leafn lasthash function to enable us to
calculate the highest hash value of a leaf1 block.  This will be used by
the directory scrubbing code to check the sanity of hashes in leaf1
directory blocks.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-06-20 10:45:21 -07:00
Darrick J. Wong c8ce540db5 xfs: remove double-underscore integer types
This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs.  This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-06-19 14:11:33 -07:00
Darrick J. Wong 7a652bbe36 xfs: fail _dir_open when readahead fails
When we open a directory, we try to readahead block 0 of the directory
on the assumption that we're going to need it soon.  If the bmbt is
corrupt, the directory will never be usable and the readahead fails
immediately, so we might as well prevent the directory from being opened
at all.  This prevents a subsequent read or modify operation from
hitting it and taking the fs offline.

NOTE: We're only checking for early failures in the block mapping, not
the readahead directory block itself.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-02-02 15:13:58 -08:00
Darrick J. Wong 2c3234d1ef xfs: rename flist/free_list to dfops
Mechanical change of flist/free_list to dfops, since they're now
deferred ops, not just a freeing list.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-08-03 11:19:29 +10:00
Dave Chinner 160ae76fa1 libxfs: directory node splitting does not have an extra block
xfsprogs source commit 4280e59dcbc4cd8e01585efe788a68eb378048e8

xfs_da3_split() has to handle all three versions of the
directory/attribute btree structure. The attr tree is v1, the dir
tre is v2 or v3. The main difference between the v1 and v2/3 trees
is the way tree nodes are split - in the v1 tree we can require a
double split to occur because the object to be inserted may be
larger than the space made by splitting a leaf. In this case we need
to do a double split - one to split the full leaf, then another to
allocate an empty leaf block in the correct location for the new
entry.  This does not happen with dir (v2/v3) formats as the objects
being inserted are always guaranteed to fit into the new space in
the split blocks.

Indeed, for directories they *may* be an extra block on this buffer
pointer. However, it's guaranteed not to be a leaf block (i.e. a
directory data block) - the directory code only ever places hash
index or free space blocks in this pointer (as a cursor of
sorts), and so to use it as a directory data block will immediately
corrupt the directory.

The problem is that the code assumes that there may be extra blocks
that we need to link into the tree once we've split the root, but
this is not true for either dir or attr trees, because the extra
attr block is always consumed by the last node split before we split
the root. Hence the linking in an extra block is always wrong at the
root split level, and this manifests itself in repair as a directory
corruption in a repaired directory, leaving the directory rebuild
incomplete.

This is a dir v2 zero-day bug - it was in the initial dir v2 commit
that was made back in February 1998.

Fix this by ensuring the linking of the blocks after the root split
never tries to make use of the extra blocks that may be held in the
cursor. They are held there for other purposes and should never be
touched by the root splitting code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-07-22 09:51:05 +10:00
Eric Sandeen 233135b763 xfs: print name of verifier if it fails
This adds a name to each buf_ops structure, so that if
a verifier fails we can print the type of verifier that
failed it.  Should be a slight debugging aid, I hope.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-01-04 16:10:19 +11:00
Brian Foster a45086e27d xfs: validate metadata LSNs against log on v5 superblocks
Since the onset of v5 superblocks, the LSN of the last modification has
been included in a variety of on-disk data structures. This LSN is used
to provide log recovery ordering guarantees (e.g., to ensure an older
log recovery item is not replayed over a newer target data structure).

While this works correctly from the point a filesystem is formatted and
mounted, userspace tools have some problematic behaviors that defeat
this mechanism. For example, xfs_repair historically zeroes out the log
unconditionally (regardless of whether corruption is detected). If this
occurs, the LSN of the filesystem is reset and the log is now in a
problematic state with respect to on-disk metadata structures that might
have a larger LSN. Until either the log catches up to the highest
previously used metadata LSN or each affected data structure is modified
and written out without incident (which resets the metadata LSN), log
recovery is susceptible to filesystem corruption.

This problem is ultimately addressed and repaired in the associated
userspace tools. The kernel is still responsible to detect the problem
and notify the user that something is wrong. Check the superblock LSN at
mount time and fail the mount if it is invalid. From that point on,
trigger verifier failure on any metadata I/O where an invalid LSN is
detected. This results in a filesystem shutdown and guarantees that we
do not log metadata changes with invalid LSNs on disk. Since this is a
known issue with a known recovery path, present a warning to instruct
the user how to recover.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-10-12 15:59:25 +11:00
Dave Chinner 5d54b8cdea Merge branch 'xfs-misc-fixes-for-4.3-4' into for-next 2015-09-01 10:30:11 +10:00
Darrick J. Wong dfdd4ac66c libxfs: bad magic number should set da block buffer error
If xfs_da3_node_read_verify() doesn't recognize the magic number of a
buffer it's just read, set the buffer error to -EFSCORRUPTED so that
the error can be sent up to userspace.  Without this patch we'll
notice the bad magic eventually while trying to traverse or change
the block, but we really ought to fail early in the verifier.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-28 14:50:03 +10:00
Dave Chinner aa493382cb Merge branch 'xfs-misc-fixes-for-4.3-2' into for-next 2015-08-20 09:28:45 +10:00
Brian Foster 7df1c170b9 xfs: swap leaf buffer into path struct atomically during path shift
The node directory lookup code uses a state structure that tracks the
path of buffers used to search for the hash of a filename through the
leaf blocks. When the lookup encounters a block that ends with the
requested hash, but the entry has not yet been found, it must shift over
to the next block and continue looking for the entry (i.e., duplicate
hashes could continue over into the next block). This shift mechanism
involves walking back up and down the state structure, replacing buffers
at the appropriate btree levels as necessary.

When a buffer is replaced, the old buffer is released and the new buffer
read into the active slot in the path structure. Because the buffer is
read directly into the path slot, a buffer read failure can result in
setting a NULL buffer pointer in an active slot. This throws off the
state cleanup code in xfs_dir2_node_lookup(), which expects to release a
buffer from each active slot. Instead, a BUG occurs due to a NULL
pointer dereference:

  BUG: unable to handle kernel NULL pointer dereference at 00000000000001e8
  IP: [<ffffffffa0585063>] xfs_trans_brelse+0x2a3/0x3c0 [xfs]
  ...
  RIP: 0010:[<ffffffffa0585063>]  [<ffffffffa0585063>] xfs_trans_brelse+0x2a3/0x3c0 [xfs]
  ...
  Call Trace:
   [<ffffffffa05250c6>] xfs_dir2_node_lookup+0xa6/0x2c0 [xfs]
   [<ffffffffa0519f7c>] xfs_dir_lookup+0x1ac/0x1c0 [xfs]
   [<ffffffffa055d0e1>] xfs_lookup+0x91/0x290 [xfs]
   [<ffffffffa05580b3>] xfs_vn_lookup+0x73/0xb0 [xfs]
   [<ffffffff8122de8d>] lookup_real+0x1d/0x50
   [<ffffffff8123330e>] path_openat+0x91e/0x1490
   [<ffffffff81235079>] do_filp_open+0x89/0x100
   ...

This has been reproduced via a parallel fsstress and filesystem shutdown
workload in a loop. The shutdown triggers the read error in the
aforementioned codepath and causes the BUG in xfs_dir2_node_lookup().

Update xfs_da3_path_shift() to update the active path slot atomically
with respect to the caller when a buffer is replaced. This ensures that
the caller always sees the old or new buffer in the slot and prevents
the NULL pointer dereference.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 10:32:33 +10:00
Dave Chinner 5461ad99ca Merge branch 'xfs-meta-uuid' into for-next 2015-07-29 11:54:21 +10:00
Eric Sandeen ce748eaa65 xfs: create new metadata UUID field and incompat flag
This adds a new superblock field, sb_meta_uuid.  If set, along with
a new incompat flag, the code will use that field on a V5 filesystem
to compare to metadata UUIDs, which allows us to change the user-
visible UUID at will.  Userspace handles the setting and clearing
of the incompat flag as appropriate, as the UUID gets changed; i.e.
setting the user-visible UUID back to the original UUID (as stored in
the new field) will remove the incompatible feature flag.

If the incompat flag is not set, this copies the user-visible UUID into
into the meta_uuid slot in memory when the superblock is read from disk;
the meta_uuid field is not written back to disk in this case.

The remainder of this patch simply switches verifiers, initializers,
etc to use the new sb_meta_uuid field.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-07-29 11:53:31 +10:00
Dave Chinner ab7bb61092 xfs: xfs_bunmapi() does not need XFS_BMAPI_METADATA flag
xfs_bunmapi() doesn't care what type of extent is being freed and
does not look at the XFS_BMAPI_METADATA flag at all. As such we can
remove the XFS_BMAPI_METADATA from all callers that use it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-07-29 11:51:01 +10:00
Fabian Frederick 29916df08d xfs: fix shadow warning in xfs_da3_root_split()
Use icnodehdr for struct xfs_da3_icnode_hdr instead of nodehdr
(already declared above).

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-03-25 14:55:25 +11:00
Dave Chinner 6044e4386c Merge branch 'xfs-misc-fixes-for-3.19-2' into for-next
Conflicts:
	fs/xfs/xfs_iops.c
2014-12-04 09:46:17 +11:00
Dave Chinner 32296f865e xfs: fix set-but-unused warnings
The kernel compile doesn't turn on these checks by default, so it's
only when I do a kernel-user sync that I find that there are lots of
compiler warnings waiting to be fixed. Fix up these set-but-unused
warnings.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-12-04 09:43:17 +11:00
Christoph Hellwig bb58e6188a xfs: move most of xfs_sb.h to xfs_format.h
More on-disk format consolidation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28 14:27:09 +11:00
Christoph Hellwig 4fb6e8ade2 xfs: merge xfs_ag.h into xfs_format.h
More on-disk format consolidation.  A few declarations that weren't on-disk
format related move into better suitable spots.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28 14:25:04 +11:00
Eric Sandeen 6ee49a20c1 xfs: don't send null bp to xfs_trans_brelse()
In this case, if bp is NULL, error is set, and we send a
NULL bp to xfs_trans_brelse, which will try to dereference it.

Test whether we actually have a buffer before we try to
free it.

Coverity spotted this.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:23:49 +10:00
Christoph Hellwig d5cf09bace xfs: require 64-bit sector_t
Trying to support tiny disks only and saving a bit memory might have
made sense on an SGI O2 15 years ago, but is pretty pointless today.

Remove the rarely tested codepath that uses various smaller in-memory
types to reduce our test matrix and make the codebase a little bit
smaller and less complicated.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-30 09:12:05 +10:00
Dave Chinner 2451337dd0 xfs: global error sign conversion
Convert all the errors the core XFs code to negative error signs
like the rest of the kernel and remove all the sign conversion we
do in the interface layers.

Errors for conversion (and comparison) found via searches like:

$ git grep " E" fs/xfs
$ git grep "return E" fs/xfs
$ git grep " E[A-Z].*;$" fs/xfs

Negation points found via searches like:

$ git grep "= -[a-z,A-Z]" fs/xfs
$ git grep "return -[a-z,A-D,F-Z]" fs/xfs
$ git grep " -[a-z].*;" fs/xfs

[ with some bits I missed from Brian Foster ]

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25 14:58:08 +10:00