09 Sep, 2015
2 commits
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Use DAX to provide support for huge pages.
Signed-off-by: Matthew Wilcox
Cc: Hillf Danton
Cc: "Kirill A. Shutemov"
Cc: Theodore Ts'o
Cc: Jan Kara
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In order to handle the !CONFIG_TRANSPARENT_HUGEPAGES case, we need to
return VM_FAULT_FALLBACK from the inlined dax_pmd_fault(), which is
defined in linux/mm.h. Given that we don't want to include
in , the easiest solution is to move the DAX-related
functions to a new header, . We could also have moved
VM_FAULT_* definitions to a new header, or a different header that isn't
quite such a boil-the-ocean header as , but this felt like
the best option.Signed-off-by: Matthew Wilcox
Cc: Hillf Danton
Cc: "Kirill A. Shutemov"
Cc: Theodore Ts'o
Cc: Jan Kara
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Sep, 2015
1 commit
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Pull xfs updates from Dave Chinner:
"There isn't a whole lot to this update - it's mostly bug fixes and
they are spread pretty much all over XFS. There are some corruption
fixes, some fixes for log recovery, some fixes that prevent unount
from hanging, a lockdep annotation rework for inode locking to prevent
false positives and the usual random bunch of cleanups and minor
improvements.Deatils:
- large rework of EFI/EFD lifecycle handling to fix log recovery
corruption issues, crashes and unmount hangs- separate metadata UUID on disk to enable changing boot label UUID
for v5 filesystems- fixes for gcc miscompilation on certain platforms and optimisation
levels- remote attribute allocation and recovery corruption fixes
- inode lockdep annotation rework to fix bugs with too many
subclasses- directory inode locking changes to prevent lockdep false positives
- a handful of minor corruption fixes
- various other small cleanups and bug fixes"
* tag 'xfs-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (42 commits)
xfs: fix error gotos in xfs_setattr_nonsize
xfs: add mssing inode cache attempts counter increment
xfs: return errors from partial I/O failures to files
libxfs: bad magic number should set da block buffer error
xfs: fix non-debug build warnings
xfs: collapse allocsize and biosize mount option handling
xfs: Fix file type directory corruption for btree directories
xfs: lockdep annotations throw warnings on non-debug builds
xfs: Fix uninitialized return value in xfs_alloc_fix_freelist()
xfs: inode lockdep annotations broke non-lockdep build
xfs: flush entire file on dio read/write to cached file
xfs: Fix xfs_attr_leafblock definition
libxfs: readahead of dir3 data blocks should use the read verifier
xfs: stop holding ILOCK over filldir callbacks
xfs: clean up inode lockdep annotations
xfs: swap leaf buffer into path struct atomically during path shift
xfs: relocate sparse inode mount warning
xfs: dquots should be stamped with sb_meta_uuid
xfs: log recovery needs to validate against sb_meta_uuid
xfs: growfs not aware of sb_meta_uuid
...
06 Sep, 2015
1 commit
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Pull vfs updates from Al Viro:
"In this one:- d_move fixes (Eric Biederman)
- UFS fixes (me; locking is mostly sane now, a bunch of bugs in error
handling ought to be fixed)- switch of sb_writers to percpu rwsem (Oleg Nesterov)
- superblock scalability (Josef Bacik and Dave Chinner)
- swapon(2) race fix (Hugh Dickins)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits)
vfs: Test for and handle paths that are unreachable from their mnt_root
dcache: Reduce the scope of i_lock in d_splice_alias
dcache: Handle escaped paths in prepend_path
mm: fix potential data race in SyS_swapon
inode: don't softlockup when evicting inodes
inode: rename i_wb_list to i_io_list
sync: serialise per-superblock sync operations
inode: convert inode_sb_list_lock to per-sb
inode: add hlist_fake to avoid the inode hash lock in evict
writeback: plug writeback at a high level
change sb_writers to use percpu_rw_semaphore
shift percpu_counter_destroy() into destroy_super_work()
percpu-rwsem: kill CONFIG_PERCPU_RWSEM
percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire()
percpu-rwsem: introduce percpu_down_read_trylock()
document rwsem_release() in sb_wait_write()
fix the broken lockdep logic in __sb_start_write()
introduce __sb_writers_{acquired,release}() helpers
ufs_inode_get{frag,block}(): get rid of 'phys' argument
ufs_getfrag_block(): tidy up a bit
...
05 Sep, 2015
1 commit
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Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g. new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files. This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else. This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink). Imagine the use
of "sudo" is something more sneaky:$ BASE="ovl"
$ MNT="$BASE/mnt"
$ LOW="$BASE/lower"
$ UP="$BASE/upper"
$ WORK="$BASE/work/ 0 0
none /proc fuse.pwn user_id=1000"
$ mkdir -p "$LOW" "$UP" "$WORK"
$ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
$ cat /proc/mounts
none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
none /proc fuse.pwn user_id=1000 0 0
$ fusermount -u /proc
$ cat /proc/mounts
cat: /proc/mounts: No such file or directoryThis fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed. Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: Kees Cook
Acked-by: Serge Hallyn
Acked-by: Jan Kara
Acked-by: Paul Moore
Cc: J. R. Okajima
Signed-off-by: Kees Cook
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
03 Sep, 2015
1 commit
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Pull core block updates from Jens Axboe:
"This first core part of the block IO changes contains:- Cleanup of the bio IO error signaling from Christoph. We used to
rely on the uptodate bit and passing around of an error, now we
store the error in the bio itself.- Improvement of the above from myself, by shrinking the bio size
down again to fit in two cachelines on x86-64.- Revert of the max_hw_sectors cap removal from a revision again,
from Jeff Moyer. This caused performance regressions in various
tests. Reinstate the limit, bump it to a more reasonable size
instead.- Make /sys/block//queue/discard_max_bytes writeable, by me.
Most devices have huge trim limits, which can cause nasty latencies
when deleting files. Enable the admin to configure the size down.
We will look into having a more sane default instead of UINT_MAX
sectors.- Improvement of the SGP gaps logic from Keith Busch.
- Enable the block core to handle arbitrarily sized bios, which
enables a nice simplification of bio_add_page() (which is an IO hot
path). From Kent.- Improvements to the partition io stats accounting, making it
faster. From Ming Lei.- Also from Ming Lei, a basic fixup for overflow of the sysfs pending
file in blk-mq, as well as a fix for a blk-mq timeout race
condition.- Ming Lin has been carrying Kents above mentioned patches forward
for a while, and testing them. Ming also did a few fixes around
that.- Sasha Levin found and fixed a use-after-free problem introduced by
the bio->bi_error changes from Christoph.- Small blk cgroup cleanup from Viresh Kumar"
* 'for-4.3/core' of git://git.kernel.dk/linux-block: (26 commits)
blk: Fix bio_io_vec index when checking bvec gaps
block: Replace SG_GAPS with new queue limits mask
block: bump BLK_DEF_MAX_SECTORS to 2560
Revert "block: remove artifical max_hw_sectors cap"
blk-mq: fix race between timeout and freeing request
blk-mq: fix buffer overflow when reading sysfs file of 'pending'
Documentation: update notes in biovecs about arbitrarily sized bios
block: remove bio_get_nr_vecs()
fs: use helper bio_add_page() instead of open coding on bi_io_vec
block: kill merge_bvec_fn() completely
md/raid5: get rid of bio_fits_rdev()
md/raid5: split bio for chunk_aligned_read
block: remove split code in blkdev_issue_{discard,write_same}
btrfs: remove bio splitting and merge_bvec_fn() calls
bcache: remove driver private bio splitting code
block: simplify bio_add_page()
block: make generic_make_request handle arbitrarily sized bios
blk-cgroup: Drop unlikely before IS_ERR(_OR_NULL)
block: don't access bio->bi_error after bio_put()
block: shrink struct bio down to 2 cache lines again
...
01 Sep, 2015
1 commit
28 Aug, 2015
4 commits
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As the code stands today, if xfs_trans_reserve() fails, we
goto out_dqrele, which does not free the allocated transaction.Fix up the goto targets to undo everything properly.
Addresses-Coverity-Id: 145571
Signed-off-by: Eric Sandeen
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
Increasing the inode cache attempt counter was apparently dropped while
refactoring the cache code and so stayed at the initial 0 value. Add the
increment back to make the runtime stats more useful.Signed-off-by: Lucas Stach
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
There is an issue with xfs's error reporting in some cases of I/O partially
failing and partially succeeding. Calls like fsync() can report success even
though not all I/O was successful in partial-failure cases such as one disk of
a RAID0 array being offline.The issue can occur when there are more than one bio per xfs_ioend struct.
Each call to xfs_end_bio() for a bio completing will write a value to
ioend->io_error. If a successful bio completes after any failed bio, no
error is reported do to it writing 0 over the error code set by any failed bio.
The I/O error information is now lost and when the ioend is completed
only success is reported back up the filesystem stack.xfs_end_bio() should only set ioend->io_error in the case of BIO_UPTODATE
being clear. ioend->io_error is initialized to 0 at allocation so only needs
to be updated by a failed bio. Also check that ioend->io_error is 0 so that
the first error reported will be the error code returned.Cc: stable@vger.kernel.org
Signed-off-by: David Jeffery
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
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
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner
25 Aug, 2015
6 commits
-
There seem to be a couple of new set-but-unused build warnings
that gcc 4.9.3 is now warning about. These are not regressions, just
the compiler being more picky.Signed-off-by: Dave Chinner
Reviewed-by: Brian Foster
Signed-off-by: Dave Chinner -
The allocsize and biosize mount options are handled identically,
other than allocsize accepting suffixes. suffix_kstrtoint handles
bare numbers just fine too, so these can be collapsed.Signed-off-by: Eric Sandeen
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
Users have occasionally reported that file type for some directory
entries is wrong. This mostly happened after updating libraries some
libraries. After some debugging the problem was traced down to
xfs_dir2_node_replace(). The function uses args->filetype as a file type
to store in the replaced directory entry however it also calls
xfs_da3_node_lookup_int() which will store file type of the current
directory entry in args->filetype. Thus we fail to change file type of a
directory entry to a proper type.Fix the problem by storing new file type in a local variable before
calling xfs_da3_node_lookup_int().cc: # 3.16 - 4.x
Reported-by: Giacomo Comes
Signed-off-by: Jan Kara
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
SO, now if we enable lockdep without enabling CONFIG_XFS_DEBUG,
the lockdep annotations throw a warning because the assert that uses
the lockdep define is not built in:fs/xfs/xfs_inode.c:367:1: warning: 'xfs_lockdep_subclass_ok' defined but not used [-Wunused-function]
xfs_lockdep_subclass_ok(So now we need to create an ifdef mess to sort this all out, because
we need to handle all the combinations of CONFIG_XFS_DEBUG=[y|n],
CONFIG_XFS_WARNING=[y|n] and CONFIG_LOCKDEP=[y|n] appropriately.Signed-off-by: Dave Chinner
Reviewed-by: Brian Foster
Signed-off-by: Dave Chinner -
xfs_alloc_fix_freelist() can sometimes jump to out_agbp_relse
without ever setting value of 'error' variable which is then
returned. This can happen e.g. when pag->pagf_init is set but AG is
for metadata and we want to allocate user data.Fix the problem by initializing 'error' to 0, which is the desired
return value when we decide to skip this group.CC: xfs@oss.sgi.com
Coverity-id: 1309714
Signed-off-by: Jan Kara
Reviewed-by: Brian Foster
Signed-off-by: Dave Chinner
20 Aug, 2015
2 commits
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Fix CONFIG_LOCKDEP=n build, because asserts I put in to ensure we
aren't overrunning lockdep subclasses in commit 0952c81 ("xfs:
clean up inode lockdep annotations") use a define that doesn't
exist when CONFIG_LOCKDEP=nOnly check the subclass limits when lockdep is actually enabled.
Signed-off-by: Dave Chinner
Reviewed-by: Eric Sandeen
Signed-off-by: Dave Chinner
19 Aug, 2015
21 commits
-
Filesystems are responsible to manage file coherency between the page
cache and direct I/O. The generic dio code flushes dirty pages over the
range of a dio to ensure that the dio read or a future buffered read
returns the correct data. XFS has generally followed this pattern,
though traditionally has flushed and invalidated the range from the
start of the I/O all the way to the end of the file. This changed after
the following commit:7d4ea3ce xfs: use ranged writeback and invalidation for direct IO
... as the full file flush was no longer necessary to deal with the
strange post-eof delalloc issues that were since fixed. Unfortunately,
we have since received complaints about performance degradation due to
the increased exclusive iolock cycles (which locks out parallel dio
submission) that occur when a file has cached pages. This does not occur
on filesystems that use the generic code as it also does not incorporate
locking.The exclusive iolock is acquired any time the inode mapping has cached
pages, regardless of whether they reside in the range of the I/O or not.
If not, the flush/inval calls do no work and the lock was cycled for no
reason.Under consideration of the cost of the exclusive iolock, update the dio
read and write handlers to flush and invalidate the entire mapping when
cached pages exist. In most cases, this increases the cost of the
initial flush sequence but eliminates the need for further lock cycles
and flushes so long as the workload does not actively mix direct and
buffered I/O. This also more closely matches historical behavior and
performance characteristics that users have come to expect.Signed-off-by: Brian Foster
Reviewed-by: Christoph Hellwig
Signed-off-by: Dave Chinner -
struct xfs_attr_leafblock contains 'entries' array which is declared
with size 1 altough it can in fact contain much more entries. Since this
array is followed by further struct members, gcc (at least in version
4.8.3) thinks that the array has the fixed size of 1 element and thus
may optimize away all accesses beyond the end of array resulting in
non-working code. This problem was only observed with userspace code in
xfsprogs, however it's better to be safe in kernel as well and have
matching kernel and xfsprogs definitions.cc:
Signed-off-by: Jan Kara
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
In the dir3 data block readahead function, use the regular read
verifier to check the block's CRC and spot-check the block contents
instead of directly calling only the spot-checking routine. This
prevents corrupted directory data blocks from being read into the
kernel, which can lead to garbage ls output and directory loops (if
say one of the entries contains slashes and other junk).cc: # 3.12 - 4.2
Signed-off-by: Darrick J. Wong
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
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
Reviewed-by: Brian Foster
Signed-off-by: Dave Chinner -
Lockdep annotations are a maintenance nightmare. Locking has to be
modified to suit the limitations of the annotations, and we're
always having to fix the annotations because they are unable to
express the complexity of locking heirarchies correctly.So, next up, we've got more issues with lockdep annotations for
inode locking w.r.t. XFS_LOCK_PARENT:- lockdep classes are exclusive and can't be ORed together
to form new classes.
- IOLOCK needs multiple PARENT subclasses to express the
changes needed for the readdir locking rework needed to
stop the endless flow of lockdep false positives involving
readdir calling filldir under the ILOCK.
- there are only 8 unique lockdep subclasses available,
so we can't create a generic solution.IOWs we need to treat the 3-bit space available to each lock type
differently:- IOLOCK uses xfs_lock_two_inodes(), so needs:
- at least 2 IOLOCK subclasses
- at least 2 IOLOCK_PARENT subclasses
- MMAPLOCK uses xfs_lock_two_inodes(), so needs:
- at least 2 MMAPLOCK subclasses
- ILOCK uses xfs_lock_inodes with up to 5 inodes, so needs:
- at least 5 ILOCK subclasses
- one ILOCK_PARENT subclass
- one RTBITMAP subclass
- one RTSUM subclassFor the IOLOCK, split the space into two sets of subclasses.
For the MMAPLOCK, just use half the space for the one subclass to
match the non-parent lock classes of the IOLOCK.
For the ILOCK, use 0-4 as the ILOCK subclasses, 5-7 for the
remaining individual subclasses.Because they are now all different, modify xfs_lock_inumorder() to
handle the nested subclasses, and to assert fail if passed an
invalid subclass. Further, annotate xfs_lock_inodes() to assert fail
if an invalid combination of lock primitives and inode counts are
passed that would result in a lockdep subclass annotation overflow.Signed-off-by: Dave Chinner
Reviewed-by: Brian Foster
Signed-off-by: Dave Chinner -
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: [] xfs_trans_brelse+0x2a3/0x3c0 [xfs]
...
RIP: 0010:[] [] xfs_trans_brelse+0x2a3/0x3c0 [xfs]
...
Call Trace:
[] xfs_dir2_node_lookup+0xa6/0x2c0 [xfs]
[] xfs_dir_lookup+0x1ac/0x1c0 [xfs]
[] xfs_lookup+0x91/0x290 [xfs]
[] xfs_vn_lookup+0x73/0xb0 [xfs]
[] lookup_real+0x1d/0x50
[] path_openat+0x91e/0x1490
[] 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
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
The sparse inodes feature is currently considered experimental. We warn
at mount time from xfs_mount_validate_sb(). This function is part of the
superblock verifier codepath, however, which means it could be invoked
repeatedly on superblock reads or writes. This is currently only
noticeable from userspace, where mkfs produces multiple warnings at
format time.As mkfs warnings were not the intent of this change, relocate the mount
time warning to xfs_fs_fill_super(), which is only invoked once and only
in kernel space.Signed-off-by: Brian Foster
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
Once the sb_uuid is changed, the wrong uuid is stamped into new
dquots on disk. Found by inspection, verified by generic/219.Signed-off-by: Dave Chinner
Reviewed-by: Eric Sandeen
Signed-off-by: Dave Chinner -
Now that sb_uuid can be changed by the user, we cannot use this to
validate the metadata blocks being recovered belong to this
filesystem. We must check against the sb_meta_uuid as that will
remain unchanged.There is a complication in this code - the superblock itself. We can
not check the sb_meta_uuid unconditionally, as that may not be set
on disk. Hence we must verify the superblock sb_uuid matches between
the log record and the in-core superblock.Found by inspection after the previous two problems were found.
Signed-off-by: Dave Chinner
Reviewed-by: Eric Sandeen
Signed-off-by: Dave Chinner -
Adding this simple change to xfstests:common/rc::_scratch_mkfs_xfs:
+ if [ $mkfs_status -eq 0 ]; then
+ xfs_admin -U generate $SCRATCH_DEV > /dev/null
+ fitriggers all sorts of errors in xfstests. xfs/104 is an example,
where growfs fails with a UUID mismatch corruption detected by
xfs_agf_write_verify() when trying to write the first new AG
headers.Fix this problem by making sure we copy the sb_meta_uuid into new
metadata written by growfs.Signed-off-by: Dave Chinner
Reviewed-by: Eric Sandeen
Signed-off-by: Dave Chinner -
After changing the UUID on a v5 filesystem, xfstests fails
immediately on a debug kernel with:XFS: Assertion failed: uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid), file: fs/xfs/xfs_inode.c, line: 799
This needs to check against the sb_meta_uuid, not the user visible
UUID that was changed.Signed-off-by: Dave Chinner
Reviewed-by: Eric Sandeen
Signed-off-by: Dave Chinner -
It's entirely possible for userspace to ask for an xattr which
does not exist.Normally, there is no problem whatsoever when we ask for such
a thing, but when we look at an obfuscated metadump image
on a debug kernel with selinux, we trip over this ASSERT in
xfs_da3_path_shift():*result = -ENOENT; /* we're out of our tree */
ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);It (more or less) only shows up in the above scenario, because
xfs_metadump obfuscates attr names, but chooses names which
keep the same hash value - and xfs_da3_node_lookup_int does:if (((retval == -ENOENT) || (retval == -ENOATTR)) &&
(blk->hashval == args->hashval)) {
error = xfs_da3_path_shift(state, &state->path, 1, 1,
&retval);IOWS, we only get down to the xfs_da3_path_shift() ASSERT
if we are looking for an xattr which doesn't exist, but we
find xattrs on disk which have the same hash, and so might be
a hash collision, so we try the path shift. When *that*
fails to find what we're looking for, we hit the assert about
XFS_DA_OP_OKNOENT.Simply setting XFS_DA_OP_OKNOENT in xfs_attr_get solves this
rather corner-case problem with no ill side effects. It's
fine for an attr name lookup to fail.Signed-off-by: Eric Sandeen
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
If a failure occurs after the bmap free list is populated and before
xfs_bmap_finish() completes successfully (which returns a partial
list on failure), the bmap free list must be cancelled. Otherwise,
the extent items on the list are never freed and a memory leak
occurs.Several random error paths throughout the code suffer this problem.
Fix these up such that xfs_bmap_cancel() is always called on error.Signed-off-by: Brian Foster
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
Several areas of code duplicate a pattern where we take the AIL lock,
check whether an item is in the AIL and remove it if so. Create a new
helper for this pattern and use it where appropriate.Signed-off-by: Brian Foster
-
The btree cursor cleanup function takes an error parameter that
affects how buffers are released from the cursor. All buffers are
released in the event of error. Several callers do not specify the
XFS_BTREE_ERROR flag in the event of error, however. This can cause
buffers to hang around locked or with an elevated hold count and
thus lead to umount hangs in the event of errors.Fix up the xfs_btree_del_cursor() callers to pass XFS_BTREE_ERROR if
the cursor is being torn down due to error.Signed-off-by: Brian Foster
Reviewed-by: Christoph Hellwig
Signed-off-by: Dave Chinner -
The root inode is read as part of the xfs_mountfs() sequence and the
reference is dropped in the event of failure after we grab the
inode. The reference drop doesn't necessarily free the inode,
however. It marks it for reclaim and potentially kicks off the
reclaim workqueue. The workqueue is destroyed further up the error
path, which means we are subject to crash if the workqueue job runs
after this point or a memory leak which is identified if the
xfs_inode_zone is destroyed (e.g., on module removal). Both of these
outcomes are reproducible via manual instrumentation of a mount
error after the root inode xfs_iget() call in xfs_mountfs().Update the xfs_mountfs() error path to cancel any potential reclaim
work items and to run a synchronous inode reclaim if the root inode
is marked for reclaim. This ensures that no jobs remain on the queue
before it is destroyed and that the root inode is freed before the
reclaim mechanism is torn down.Signed-off-by: Brian Foster
Reviewed-by: Christoph Hellwig
Signed-off-by: Dave Chinner -
The first 4 bytes of every basic block in the physical log is stamped
with the current lsn. To support this mechanism, the log record header
(first block of each new log record) contains space for the original
first byte of each log record block before it is replaced with the lsn.
The log record header has space for 32k worth of blocks. The version 2
log adds new extended record headers for each additional 32k worth of
blocks beyond what is supported by the record header.The log record checksum incorporates the log record header, the extended
headers and the record payload. xlog_cksum() checksums the extended
headers based on log->l_iclog_heads, which specifies the number of
extended headers in a log record based on the log buffer size mount
option. The log buffer size is variable, however, and thus means the
checksum can be calculated differently based on how a filesystem is
mounted. This is problematic if a filesystem crashes and recovery occurs
on a subsequent mount using a different log buffer size. For example,
crash an active filesystem that is mounted with the default (32k)
logbsize, attempt remount/recovery using '-o logbsize=64k' and the mount
fails on or warns about log checksum failures.To avoid this problem, update xlog_cksum() to calculate the checksum
based on the size of the log buffer according to the log record. The
size is already included in the h_size field of the log record header
and thus is available at log recovery time. Extended log record headers
are also only written when the log record is large enough to require
them. This makes checksum calculation of log records consistent with the
extended record header mechanism as well as how on-disk records are
checksummed with various log buffer size mount options.Signed-off-by: Brian Foster
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
Inode cluster buffers are invalidated and cancelled when inode chunks
are freed to notify log recovery that previous logged updates to the
metadata buffer should be skipped. This ensures that log recovery does
not overwrite buffers that might have already been reused.On v4 filesystems, inode chunk allocation and inode updates are logged
via the cluster buffers and thus cancellation is easily detected via
buffer cancellation items. v5 filesystems use the new icreate
transaction, which uses logical logging and ordered buffers to log a
full inode chunk allocation at once. The resulting icreate item often
spans multiple inode cluster buffers.Log recovery checks for cancelled buffers when processing icreate log
items, but it has a couple problems. First, it uses the full length of
the inode chunk rather than the cluster size. Second, it uses the length
in FSB units rather than BB units. Either of these problems prevent
icreate recovery from identifying cancelled buffers and thus inode
initialization proceeds unconditionally.Update xlog_recover_do_icreate_pass2() to iterate the icreate range in
cluster sized increments and check each increment for cancellation.
Since icreate is currently only used for the minimum atomic inode chunk
allocation, we expect that either all or none of the buffers will be
cancelled. Cancel the icreate if at least one buffer is cancelled to
avoid making a bad situation worse by initializing a partial inode
chunk, but detect such anomalies and warn the user.Signed-off-by: Brian Foster
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner -
Various log items have recovery tracepoints to identify whether a
particular log item is recovered or cancelled. Add the equivalent
tracepoints for the icreate transaction.Signed-off-by: Brian Foster
Reviewed-by: Christoph Hellwig
Signed-off-by: Dave Chinner -
Log recovery occurs in two phases at mount time. In the first phase,
EFIs and EFDs are processed and potentially cancelled out. EFIs without
EFD objects are inserted into the AIL for processing and recovery in the
second phase. xfs_mountfs() runs various other operations between the
phases and is thus subject to failure. If failure occurs after the first
phase but before the second, pending EFIs sit on the AIL, pin it and
cause the mount to hang.Update the mount sequence to ensure that pending EFIs are cancelled in
the event of failure. Add a recovery cancellation mechanism to iterate
the AIL and cancel all EFI items when requested. Plumb cancellation
support through the log mount finish helper and update xfs_mountfs() to
invoke cancellation in the event of failure after recovery has started.Signed-off-by: Brian Foster
Reviewed-by: Dave Chinner
Signed-off-by: Dave Chinner
