xchk_get_inode is not quite the right function to be calling from the
inode scrubber setup function. The common get_inode function either
gets an inode and installs it in the scrub context, or it returns an
error code explaining what happened. This is acceptable for most file
scrubbers because it is not in their scope to fix corruptions in the
inode core and fork areas that cause iget to fail.
Dealing with these problems is within the scope of the inode scrubber,
however. If iget fails with EFSCORRUPTED, we need to xchk_inode to flag
that as corruption. Since we can't get our hands on an incore inode, we
need to hold the AGI to prevent inode allocation activity so that
nothing changes in the inode metadata.
Looking ahead to the inode core repair patches, we will also need to
hold the AGI buffer into xrep_inode so that we can make modifications to
the xfs_dinode structure without any other thread swooping in to
allocate or free the inode.
Adapt the xchk_get_inode into xchk_setup_inode since this is a one-off
use case where the error codes we check for are a little different, and
the return state is much different from the common function.
xchk_setup_inode prepares to check or repair an inode record, so it must
continue the scrub operation even if the inode/inobt verifiers cause
xfs_iget to return EFSCORRUPTED. This is done by attaching the locked
AGI buffer to the scrub transaction and returning 0 to move on to the
actual scrub. (Later, the online inode repair code will also want the
xfs_imap structure so that it can reset the ondisk xfs_dinode
structure.)
xchk_get_inode retrieves an inode on behalf of a scrubber that operates
on an incore inode -- data/attr/cow forks, directories, xattrs,
symlinks, parent pointers, etc. If the inode/inobt verifiers fail and
xfs_iget returns EFSCORRUPTED, we want to exit to userspace (because the
caller should be fix the inode first) and drop everything we acquired
along the way.
A behavior common to both functions is that it's possible that xfs_scrub
asked for a scrub-by-handle concurrent with the inode being freed or the
passed-in inumber is invalid. In this case, we call xfs_imap to see if
the inobt index thinks the inode is allocated, and return ENOENT
("nothing to check here") to userspace if this is not the case. The
imap lookup is why both functions call xchk_iget_agi.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Dave Chinner suggested renaming this function to make more obvious what
it does. The function returns an incore inode to callers that want to
scrub a metadata structure that hangs off an inode. If the iget fails
with EINVAL, it will single-step the loading process to distinguish
between actually free inodes or impossible inumbers (ENOENT);
discrepancies between the inobt freemask and the free status in the
inode record (EFSCORRUPTED). Any other negative errno is returned
unchanged.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
In commit d658e, we tried to improve the robustnes of xchk_get_inode in
the face of EINVAL returns from iget by calling xfs_imap to see if the
inobt itself thinks that the inode is allocated. Unfortunately, that
commit didn't consider the possibility that the inode gets allocated
after iget but before imap. In this case, the imap call will succeed,
but we turn that into a corruption error and tell userspace the inode is
corrupt.
Avoid this false corruption report by grabbing the AGI header and
retrying the iget before calling imap. If the iget succeeds, we can
proceed with the usual scrub-by-handle code. Fix all the incorrect
comments too, since unreadable/corrupt inodes no longer result in EINVAL
returns.
Fixes: d658e72b4a ("xfs: distinguish between corrupt inode and invalid inum in xfs_scrub_get_inode")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Right now, there are statements scattered all over the online fsck
codebase about how we can't use XFS_IGET_DONTCACHE because of concerns
about scrub's unusual practice of releasing inodes with transactions
held.
However, iget is the wrong place to handle this -- the DONTCACHE state
doesn't matter at all until we try to *release* the inode, and here we
get things wrong in multiple ways:
First, if we /do/ have a transaction, we must NOT drop the inode,
because the inode could have dirty pages, dropping the inode will
trigger writeback, and writeback can trigger a nested transaction.
Second, if the inode already had an active reference and the DONTCACHE
flag set, the icache hit when scrub grabs another ref will not clear
DONTCACHE. This is sort of by design, since DONTCACHE is now used to
initiate cache drops so that sysadmins can change a file's access mode
between pagecache and DAX.
Third, if we do actually have the last active reference to the inode, we
can set DONTCACHE to avoid polluting the cache. This is the /one/ case
where we actually want that flag.
Create an xchk_irele helper to encode all that logic and switch the
online fsck code to use it. Since this now means that nearly all
scrubbers use the same xfs_iget flags, we can wrap them too.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Jan Kara pointed out that rename() doesn't lock a subdirectory that is
being moved from one parent to another, even though the move requires an
update to the subdirectory's dotdot entry. This means that it's *not*
sufficient to hold a directory's IOLOCK to stabilize the dotdot entry.
We must hold the ILOCK of both the child and the alleged parent, and
there's no use in holding the parent's IOLOCK.
With that in mind, we can get rid of all the messy code that tries to
grab the parent's IOLOCK, which means we don't need to let go of the
ILOCK of the directory whose parent we are checking. We still have to
use nonblocking mode to take the ILOCK of the alleged parent, so the
revalidation loop has to stay.
However, we can remove the retry counter, since threads aren't supposed
to hold the ILOCK for long periods of time. Remove the inverted ilock
helper from the common code since nobody uses it. Remove the entire
source of -EDEADLOCK-based "retry harder" scrub executions.
Link: https://lore.kernel.org/linux-xfs/20230117123735.un7wbamlbdihninm@quack3/
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
In the previous patch, we added jump labels to the intent drain code so
that regular filesystem operations need not pay the price of checking
for someone (scrub) waiting on intents to drain from some part of the
filesystem when that someone isn't running.
However, I observed that xfs/285 now spends a lot more time pushing the
AIL from the inode btree scrubber than it used to. This is because the
inobt scrubber will try push the AIL to try to get logged inode cores
written to the filesystem when it sees a weird discrepancy between the
ondisk inode and the inobt records. This AIL push is triggered when the
setup function sees TRY_HARDER is set; and the requisite EDEADLOCK
return is initiated when the discrepancy is seen.
The solution to this performance slow down is to use a different result
code (ECHRNG) for scrub code to signal that it needs to wait for
deferred intent work items to drain out of some part of the filesystem.
When this happens, set a new scrub state flag (XCHK_NEED_DRAIN) so that
setup functions will activate the jump label.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
To reduce the runtime overhead even further when online fsck isn't
running, use a static branch key to decide if we call wake_up on the
drain. For compilers that support jump labels, the call to wake_up is
replaced by a nop sled when nobody is waiting for intents to drain.
From my initial microbenchmarking, every transition of the static key
between the on and off states takes about 22000ns to complete; this is
paid entirely by the xfs_scrub process. When the static key is off
(which it should be when fsck isn't running), the nop sled adds an
overhead of approximately 0.36ns to runtime code. The post-atomic
lockless waiter check adds about 0.03ns, which is basically free.
For the few compilers that don't support jump labels, runtime code pays
the cost of calling wake_up on an empty waitqueue, which was observed to
be about 30ns. However, most architectures that have sufficient memory
and CPU capacity to run XFS also support jump labels, so this is not
much of a worry.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Update the copyright years in the scrub/ source code files. This isn't
required, but it's helpful to remind myself just how long it's taken to
develop this feature.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Fix the spdx tags to match current practice, and update the author
contact information.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
If the program calling online fsck is terminated with a fatal signal,
bail out to userspace by returning EINTR, not EAGAIN. EAGAIN is used by
scrubbers to indicate that we should try again with more resources
locked, and not to indicate that the operation was cancelled. The
miswiring is mostly harmless, but it shows up in the trace data.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
This patch prepares scrub to deal with the possibility of tearing down
entire AGs by changing the order of resource acquisition to match the
rest of the XFS codebase. In other words, scrub now grabs AG resources
in order of: perag structure, then AGI/AGF/AGFL buffers, then btree
cursors; and releases them in reverse order.
This requires us to distinguish xchk_ag_init callers -- some are
responding to a user request to check AG metadata, in which case we can
return ENOENT to userspace; but other callers have an ondisk reference
to an AG that they're trying to cross-reference. In this second case,
the lack of an AG means there's ondisk corruption, since ondisk metadata
cannot point into nonexistent space.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Now that the scrub context stores a pointer to the file that was used to
invoke the scrub call, the struct xfs_inode pointer that we passed to
all the setup functions is no longer necessary. This is only ever used
if the caller wants us to scrub the metadata of the open file.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Functions called by this function cannot fail, so get rid of the return
and error checking.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Since xchk_ag_read_headers initializes fields in struct xchk_ag, we
might as well set the AG number and save the callers the trouble.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Christoph Hellwig complained about the following soft lockup warning
when running scrub after generic/175 when preemption is disabled and
slub debugging is enabled:
watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [xfs_scrub:161]
Modules linked in:
irq event stamp: 41692326
hardirqs last enabled at (41692325): [<ffffffff8232c3b7>] _raw_0
hardirqs last disabled at (41692326): [<ffffffff81001c5a>] trace0
softirqs last enabled at (41684994): [<ffffffff8260031f>] __do_e
softirqs last disabled at (41684987): [<ffffffff81127d8c>] irq_e0
CPU: 3 PID: 16189 Comm: xfs_scrub Not tainted 5.4.0-rc3+ #30
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.124
RIP: 0010:_raw_spin_unlock_irqrestore+0x39/0x40
Code: 89 f3 be 01 00 00 00 e8 d5 3a e5 fe 48 89 ef e8 ed 87 e5 f2
RSP: 0018:ffffc9000233f970 EFLAGS: 00000286 ORIG_RAX: ffffffffff3
RAX: ffff88813b398040 RBX: 0000000000000286 RCX: 0000000000000006
RDX: 0000000000000006 RSI: ffff88813b3988c0 RDI: ffff88813b398040
RBP: ffff888137958640 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea00042b0c00
R13: 0000000000000001 R14: ffff88810ac32308 R15: ffff8881376fc040
FS: 00007f6113dea700(0000) GS:ffff88813bb80000(0000) knlGS:00000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6113de8ff8 CR3: 000000012f290000 CR4: 00000000000006e0
Call Trace:
free_debug_processing+0x1dd/0x240
__slab_free+0x231/0x410
kmem_cache_free+0x30e/0x360
xchk_ag_btcur_free+0x76/0xb0
xchk_ag_free+0x10/0x80
xchk_bmap_iextent_xref.isra.14+0xd9/0x120
xchk_bmap_iextent+0x187/0x210
xchk_bmap+0x2e0/0x3b0
xfs_scrub_metadata+0x2e7/0x500
xfs_ioc_scrub_metadata+0x4a/0xa0
xfs_file_ioctl+0x58a/0xcd0
do_vfs_ioctl+0xa0/0x6f0
ksys_ioctl+0x5b/0x90
__x64_sys_ioctl+0x11/0x20
do_syscall_64+0x4b/0x1a0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
If preemption is disabled, all metadata buffers needed to perform the
scrub are already in memory, and there are a lot of records to check,
it's possible that the scrub thread will run for an extended period of
time without sleeping for IO or any other reason. Then the watchdog
timer or the RCU stall timeout can trigger, producing the backtrace
above.
To fix this problem, call cond_resched() from the scrub thread so that
we back out to the scheduler whenever necessary.
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Teach online scrub how to check the filesystem summary counters. We use
the incore delalloc block counter along with the incore AG headers to
compute expected values for fdblocks, icount, and ifree, and then check
that the percpu counter is within a certain threshold of the expected
value. This is done to avoid having to freeze or otherwise lock the
filesystem, which means that we're only checking that the counters are
fairly close, not that they're exactly correct.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The forthcoming summary counter patch races with regular filesystem
activity to compute rough expected values for the counters. This design
was chosen to avoid having to freeze the entire filesystem to check the
counters, but while that's running we'd prefer to minimize background
reclamation activity to reduce the perturbations to the incore free
block count. Therefore, provide a way for scrubbers to disable
background posteof and cowblock reclamation.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Only certain functions actually change the contents of an
xfs_owner_info; the rest can accept a const struct pointer. This will
enable us to save stack space by hoisting static owner info types to
be const global variables.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Now that we've shortened everything, fix up all the indentation and
whitespace problems. There are no functional changes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Shorten the name of the online fsck context structure. Whitespace
damage will be fixed by a subsequent patch. There are no functional
changes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Shorten all the metadata checking xfs_scrub_ prefixes to xchk_. After
this, the only xfs_scrub* symbols are the ones that pertain to both
scrub and repair. Whitespace damage will be fixed in a subsequent
patch. There are no functional changes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
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>
For repairs, we need to reserve at least as many blocks as we think
we're going to need to rebuild the data structure, and we're going to
need some helpers to roll transactions while maintaining locks on the AG
headers so that other threads cannot wander into the middle of a repair.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Grab and hold the per-AG data across a scrub run whenever relevant.
This helps us avoid repeated trips through rcu and the radix tree
in the repair code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
This function is basically a generic AGFL block iterator, so promote it
to libxfs ahead of online repair wanting to use it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
In normal operation, the XFS convention is to take an inode's iolock
and then allocate a transaction. However, when scrubbing parent inodes
this is inverted -- we allocated the transaction to do the scrub, and
now we're trying to grab the parent's iolock. This can lead to ABBA
deadlocks: some thread grabbed the parent's iolock and is waiting for
space for a transaction while our parent scrubber is sitting on a
transaction trying to get the parent's iolock.
Therefore, convert all iolock attempts to use trylock; if that fails,
they can use the existing mechanisms to back off and try again.
The ABBA deadlock didn't happen with a non-repair scrub because the
transactions don't reserve any space, but repair scrubs require
reservation in order to update metadata. However, any other concurrent
metadata update (e.g. directory create in the parent) could also induce
this deadlock with the parent scrubber.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Replace the quota scrubber's open-coded data fork scrubber with a
redirected call to the bmapbtd scrubber. This strengthens the quota
scrub to include all the cross-referencing that it does.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Don't bother looking for cross-referencing problems if the metadata is
already corrupt or we've already found a cross-referencing problem.
Since we added a helper function for flags testing, convert existing
users to use it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Since the transaction allocation helper is about to become more complex,
move it to common.c and remove the redundant parameters.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Now that we no longer do raw inode buffer scrubbing, the bp parameter is
no longer used anywhere we're dealing with an inode, so remove it and
all the useless NULL parameters that go with it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Whenever we load a buffer, explicitly re-call the structure verifier to
ensure that memory isn't corrupting things.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
When scrubbing various btrees, we should cross-reference the records
with the reverse mapping btree and ensure that traversing the btree
finds the same number of blocks that the rmapbt thinks are owned by
that btree.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Create some helper functions that we'll use later to deal with problems
we might encounter while cross referencing metadata with other metadata.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
There were ad-hoc checks for some scrub types but not others;
mark each scrub type with ... it's type, and use that to validate
the allowed and/or required input fields.
Moving these checks out of xfs_scrub_setup_ag_header makes it
a thin wrapper, so unwrap it in the process.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
[darrick: add xfs_ prefix to enum, check scrub args after checking type]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
There are two ways to scrub an inode -- calling xfs_iget and checking
the raw inode core, or by loading the inode cluster buffer and checking
the on-disk contents directly. The second method is only useful if
_iget fails the verifiers; when this is the case, sc->ip is NULL and
calling the tracepoint will cause a system crash.
Therefore, pass the raw inode number directly into the _preen and
_warning functions.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Perform some quick sanity testing of the disk quota information.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Perform simple tests of the realtime bitmap and summary.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Scrub parent pointers, sort of. For directories, we can ride the
'..' entry up to the parent to confirm that there's at most one
dentry that points back to this directory.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Create the infrastructure to scrub symbolic link data.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Scrub the hash tree, keys, and values in an extended attribute structure.
Refactor the attribute code to use the transaction if the caller supplied
one to avoid buffer deadocks.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.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>
Scrub an individual inode's block mappings to make sure they make sense.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Plumb in the pieces necessary to check the refcount btree. If rmap is
available, check the reference count by performing an interval query
against the rmapbt.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Check the reverse mapping records to make sure that the contents
make sense.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Check the records of the inode btrees to make sure that the values
make sense given the inode records themselves.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Check the extent records free space btrees to ensure that the values
look sane.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Check the block references in the AGF and AGFL headers to make sure
they make sense.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Ensure that the geometry presented in the backup superblocks matches
the primary superblock so that repair can recover the filesystem if
that primary gets corrupted.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add some helpers to enable us to lock an AG's headers, create btree
cursors for all btrees in that allocation group, and clean up
afterwards.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>