I was poking around in the directory code while diagnosing online fsck
bugs, and noticed that xfs_readdir doesn't actually take the directory
ILOCK when it calls xfs_dir2_isblock. xfs_dir_open most probably loaded
the data fork mappings and the VFS took i_rwsem (aka IOLOCK_SHARED) so
we're protected against writer threads, but we really need to follow the
locking model like we do in other places.
To avoid unnecessarily cycling the ILOCK for fairly small directories,
change the block/leaf _getdents functions to consume the ILOCK hold that
the parent readdir function took to decide on a _getdents implementation.
It is ok to cycle the ILOCK in readdir because the VFS takes the IOLOCK
in the appropriate mode during lookups and writes, and we don't want to
be holding the ILOCK when we copy directory entries to userspace in case
there's a page fault. We really only need it to protect against data
fork lookups, like we do for other files.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Remove the shouty macro and instead use the inline function that
matches other state/feature check wrapper naming. This conversion
was done with sed.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Convert the xfs_sb_version_hasfoo() to checks against
mp->m_features. Checks of the superblock itself during disk
operations (e.g. in the read/write verifiers and the to/from disk
formatters) are not converted - they operate purely on the
superblock state. Everything else should use the mount features.
Large parts of this conversion were done with sed with commands like
this:
for f in `git grep -l xfs_sb_version_has fs/xfs/*.c`; do
sed -i -e 's/xfs_sb_version_has\(.*\)(&\(.*\)->m_sb)/xfs_has_\1(\2)/' $f
done
With manual cleanups for things like "xfs_has_extflgbit" and other
little inconsistencies in naming.
The result is ia lot less typing to check features and an XFS binary
size reduced by a bit over 3kB:
$ size -t fs/xfs/built-in.a
text data bss dec hex filenam
before 1130866 311352 484 1442702 16038e (TOTALS)
after 1127727 311352 484 1439563 15f74b (TOTALS)
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Just check for an inline format fork instead of the using the equivalent
in-memory XFS_IFINLINE flag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Move the XFS_IFEXTENTS check from the callers into xfs_iread_extents to
simplify the code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
In preparation of removing the historic icinode struct, move the on-disk
size field into the containing xfs_inode structure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Both the data and attr fork have a format that is stored in the legacy
idinode. Move it into the xfs_ifork structure instead, where it uses
up padding.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Commit 263dde869b ("xfs: cleanup xfs_dir2_block_getdents") introduced
a getdents regression, when it converted the pointer arithmetics to
offset calculations: offset is updated in the loop already for the next
iteration, but the updated offset value is used incorrectly in two
places, where we should have used the not-yet-updated value.
This caused for example "git clean -ffdx" failures to cleanup certain
directory structures when running in a container.
Fix the regression by making sure we use proper offset in the loop body.
Thanks to Christoph Hellwig for suggestion how to best fix the code.
Cc: Christoph Hellwig <hch@lst.de>
Fixes: 263dde869b ("xfs: cleanup xfs_dir2_block_getdents")
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.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>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Move the code for reading an already mapped block into
xfs_da3_node_read_mapped, which is the only caller ever passing a block
number in the mappedbno argument and replace the mappedbno argument with
the simple xfs_dabuf_get flags.
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>
Replace the mappedbno argument with the simple flags for xfs_da_reada_buf
and xfs_dir3_data_readahead.
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>
Convert the last of the open coded corruption check and report idioms to
use the XFS_IS_CORRUPT macro.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Replace the ->data_get_ftype and ->data_put_ftype dir ops methods with
directly called xfs_dir2_data_get_ftype and xfs_dir2_data_put_ftype
helpers that takes care of the differences between the directory format
with and without the file type field.
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>
Move the data block fixed offsets towards our structure for dir/attr
geometry parameters.
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>
Replace the ->data_entsize dir ops method with a directly called
xfs_dir2_data_entsize helper that takes care of the differences between
the directory format with and without the file type field.
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>
All the callers really want an offset into the buffer, so adopt
the helper to return that instead.
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>
Use an offset as the main means for iteration, and only do pointer
arithmetics to find the data/unused entries.
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>
Use an offset as the main means for iteration, and only do pointer
arithmetics to find the data/unused entries.
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>
The data_dotdot_offset value is always equal to data_entry_offset plus
the fixed size of the "." entry. Right now calculating that fixed size
requires an indirect call, but by the end of this series it will be
an inline function that can be constant folded.
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>
The data_dot_offset value is always equal to data_entry_offset given
that "." is always the first entry in the directory.
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>
Replace the ->sf_get_ftype and ->sf_put_ftype dir ops methods with
directly called xfs_dir2_sf_get_ftype and xfs_dir2_sf_put_ftype helpers
that takes care of the differences between the directory format with and
without the file type field.
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>
Replace the ->sf_get_ino and ->sf_put_ino dir ops methods with directly
called xfs_dir2_sf_get_ino and xfs_dir2_sf_put_ino helpers that take care
of the difference between the directory format with and without the file
type field. Also move xfs_dir2_sf_get_parent_ino and
xfs_dir2_sf_put_parent_ino to xfs_dir2_sf.c with the rest of the
low-level short form entry handling and use XFS_MAXINUMBER istead of
opencoded constants.
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>
Just check for file-type enabled directories directly.
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>
The parent inode handling is the same for all directory format variants,
just use direct calls instead of going through a pointless indirect
call.
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>
Actually call namecheck on directory entry names before we hand them
over to userspace.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
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>
The inode geometry structure isn't related to ondisk format; it's
support for the mount structure. Move it to xfs_shared.h.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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>
In xfs_scrub_dir_rec, we must walk through the directory block entries
to arrive at the offset given by the hash structure. If we blindly
trust the hash address, we can end up midway into a directory entry and
stray outside the block. Found by lastbit fuzzing lents[3].address in
xfs/390 with KASAN enabled.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a new xfs_iext_cursor structure to hide the direct extent map
index manipulations. In addition to the existing lookup/get/insert/
remove and update routines new primitives to get the first and last
extent cursor, as well as moving up and down by one extent are
provided. Also new are convenience to increment/decrement the
cursor and retreive the new extent, as well as to peek into the
previous/next extent without updating the cursor and last but not
least a macro to iterate over all extents in a fork.
[darrick: rename for_each_iext to for_each_xfs_iext]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
Scrub the hash tree and all the entries in a directory.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Teach the directory reading functions to pass along a transaction context
if one was supplied. The directory scrub code will use transactions to
lock buffers and avoid deadlocking with itself in the case of loops.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
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>
Currently, the dir2 leaf block getdents function uses a complex state
tracking mechanism to create a shadow copy of the block mappings and
then uses the shadow copy to schedule readahead. Since the read and
readahead functions are perfectly capable of reading the mappings
themselves, we can tear all that out in favor of a simpler function that
simply keeps pushing the readahead window further out.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Directory block readahead uses a complex iteration mechanism to map
between high-level directory blocks and underlying physical extents.
This mechanism attempts to traverse the higher-level dir blocks in a
manner that handles multi-fsb directory blocks and simultaneously
maintains a reference to the corresponding physical blocks.
This logic doesn't handle certain (discontiguous) physical extent
layouts correctly with multi-fsb directory blocks. For example,
consider the case of a 4k FSB filesystem with a 2 FSB (8k) directory
block size and a directory with the following extent layout:
EXT: FILE-OFFSET BLOCK-RANGE AG AG-OFFSET TOTAL
0: [0..7]: 88..95 0 (88..95) 8
1: [8..15]: 80..87 0 (80..87) 8
2: [16..39]: 168..191 0 (168..191) 24
3: [40..63]: 5242952..5242975 1 (72..95) 24
Directory block 0 spans physical extents 0 and 1, dirblk 1 lies
entirely within extent 2 and dirblk 2 spans extents 2 and 3. Because
extent 2 is larger than the directory block size, the readahead code
erroneously assumes the block is contiguous and issues a readahead
based on the physical mapping of the first fsb of the dirblk. This
results in read verifier failure and a spurious corruption or crc
failure, depending on the filesystem format.
Further, the subsequent readahead code responsible for walking
through the physical table doesn't correctly advance the physical
block reference for dirblk 2. Instead of advancing two physical
filesystem blocks, the first iteration of the loop advances 1 block
(correctly), but the subsequent iteration advances 2 more physical
blocks because the next physical extent (extent 3, above) happens to
cover more than dirblk 2. At this point, the higher-level directory
block walking is completely off the rails of the actual physical
layout of the directory for the respective mapping table.
Update the contiguous dirblock logic to consider the current offset
in the physical extent to avoid issuing directory readahead to
unrelated blocks. Also, update the mapping table advancing code to
consider the current offset within the current dirblock to avoid
advancing the mapping reference too far beyond the dirblock.
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>
Carlos had a case where "find" seemed to start spinning
forever and never return.
This was on a filesystem with non-default multi-fsb (8k)
directory blocks, and a fragmented directory with extents
like this:
0:[0,133646,2,0]
1:[2,195888,1,0]
2:[3,195890,1,0]
3:[4,195892,1,0]
4:[5,195894,1,0]
5:[6,195896,1,0]
6:[7,195898,1,0]
7:[8,195900,1,0]
8:[9,195902,1,0]
9:[10,195908,1,0]
10:[11,195910,1,0]
11:[12,195912,1,0]
12:[13,195914,1,0]
...
i.e. the first extent is a contiguous 2-fsb dir block, but
after that it is fragmented into 1 block extents.
At the top of the readdir path, we allocate a mapping array
which (for this filesystem geometry) can hold 10 extents; see
the assignment to map_info->map_size. During readdir, we are
therefore able to map extents 0 through 9 above into the array
for readahead purposes. If we count by 2, we see that the last
mapped index (9) is the first block of a 2-fsb directory block.
At the end of xfs_dir2_leaf_readbuf() we have 2 loops to fill
more readahead; the outer loop assumes one full dir block is
processed each loop iteration, and an inner loop that ensures
that this is so by advancing to the next extent until a full
directory block is mapped.
The problem is that this inner loop may step past the last
extent in the mapping array as it tries to reach the end of
the directory block. This will read garbage for the extent
length, and as a result the loop control variable 'j' may
become corrupted and never fail the loop conditional.
The number of valid mappings we have in our array is stored
in map->map_valid, so stop this inner loop based on that limit.
There is an ASSERT at the top of the outer loop for this
same condition, but we never made it out of the inner loop,
so the ASSERT never fired.
Huge appreciation for Carlos for debugging and isolating
the problem.
Debugged-and-analyzed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Tested-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
When we're reading or writing the data fork of an inline directory,
check the contents to make sure we're not overflowing buffers or eating
garbage data. xfs/348 corrupts an inline symlink into an inline
directory, triggering a buffer overflow bug.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
v2: add more checks consistent with _dir2_sf_check and make the verifier
usable from anywhere.
This patch drops the XFS-own i_iolock and uses the VFS i_rwsem which
recently replaced i_mutex instead. This means we only have to take
one lock instead of two in many fast path operations, and we can
also shrink the xfs_inode structure. Thanks to the xfs_ilock family
there is very little churn, the only thing of note is that we need
to switch to use the lock_two_directory helper for taking the i_rwsem
on two inodes in a few places to make sure our lock order matches
the one used in the VFS.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If the size of an inline directory is so small that it doesn't
even cover the required header size, return an error to userspace
instead of ASSERTing and returning 0 like everything's ok.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reported-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
There's a three-process deadlock involving shared/exclusive barriers
and inverted lock orders in the directory readdir implementation.
It's a pre-existing problem with lock ordering, exposed by the
VFS parallelisation code.
process 1 process 2 process 3
--------- --------- ---------
readdir
iolock(shared)
get_leaf_dents
iterate entries
ilock(shared)
map, lock and read buffer
iunlock(shared)
process entries in buffer
.....
readdir
iolock(shared)
get_leaf_dents
iterate entries
ilock(shared)
map, lock buffer
<blocks>
finish ->iterate_shared
file_accessed()
->update_time
start transaction
ilock(excl)
<blocks>
.....
finishes processing buffer
get next buffer
ilock(shared)
<blocks>
And that's the deadlock.
Fix this by dropping the current buffer lock in process 1 before
trying to map the next buffer. This means we keep the lock order of
ilock -> buffer lock intact and hence will allow process 3 to make
progress and drop it's ilock(shared) once it is done.
Reported-by: Xiong Zhou <xzhou@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Move the di_mode value from the xfs_icdinode to the VFS inode, reducing
the xfs_icdinode byte another 2 bytes and collapsing another 2 byte hole
in the structure.
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>
This patch modifies the stats counting macros and the callers
to those macros to properly increment, decrement, and add-to
the xfs stats counts. The counts for global and per-fs stats
are correctly advanced, and cleared by writing a "1" to the
corresponding clear file.
global counts: /sys/fs/xfs/stats/stats
per-fs counts: /sys/fs/xfs/sda*/stats/stats
global clear: /sys/fs/xfs/stats/stats_clear
per-fs clear: /sys/fs/xfs/sda*/stats/stats_clear
[dchinner: cleaned up macro variables, removed CONFIG_FS_PROC around
stats structures and macros. ]
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The recent change to the readdir locking made in 40194ec ("xfs:
reinstate the ilock in xfs_readdir") for CXFS directory sanity was
probably the wrong thing to do. Deep in the readdir code we
can take page faults in the filldir callback, and so taking a page
fault while holding an inode ilock creates a new set of locking
issues that lockdep warns all over the place about.
The locking order for regular inodes w.r.t. page faults is io_lock
-> pagefault -> mmap_sem -> ilock. The directory readdir code now
triggers ilock -> page fault -> mmap_sem. While we cannot deadlock
at this point, it inverts all the locking patterns that lockdep
normally sees on XFS inodes, and so triggers lockdep. We worked
around this with commit 93a8614 ("xfs: fix directory inode iolock
lockdep false positive"), but that then just moved the lockdep
warning to deeper in the page fault path and triggered on security
inode locks. Fixing the shmem issue there just moved the lockdep
reports somewhere else, and now we are getting false positives from
filesystem freezing annotations getting confused.
Further, if we enter memory reclaim in a readdir path, we now get
lockdep warning about potential deadlocks because the ilock is held
when we enter reclaim. This, again, is different to a regular file
in that we never allow memory reclaim to run while holding the ilock
for regular files. Hence lockdep now throws
ilock->kmalloc->reclaim->ilock warnings.
Basically, the problem is that the ilock is being used to protect
the directory data and the inode metadata, whereas for a regular
file the iolock protects the data and the ilock protects the
metadata. From the VFS perspective, the i_mutex serialises all
accesses to the directory data, and so not holding the ilock for
readdir doesn't matter. The issue is that CXFS doesn't access
directory data via the VFS, so it has no "data serialisaton"
mechanism. Hence we need to hold the IOLOCK in the correct places to
provide this low level directory data access serialisation.
The ilock can then be used just when the extent list needs to be
read, just like we do for regular files. The directory modification
code can take the iolock exclusive when the ilock is also taken,
and this then ensures that readdir is correct excluded while
modifications are in progress.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
These functions are needed in userspace for repair and mkfs to
do the right thing. Move them to libxfs so they can be easily
shared.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
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>
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>
More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
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>
XFS_ERROR was designed long ago to trap return values, but it's not
runtime configurable, it's not consistently used, and we can do
similar error trapping with ftrace scripts and triggers from
userspace.
Just nuke XFS_ERROR and associated bits.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The kbuild test robot reported:
>> fs/xfs/xfs_dir2_readdir.c:672:41: sparse: Using plain integer as NULL pointer
Fix it.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Darrick J. Wong
Dave Chinner
Christoph Hellwig
Tommi Rantala
Darrick J. Wong
Eric Sandeen
Brian Foster
Eric Sandeen
Dave Chinner
Bill O'Donnell