With gcc-5:
In file included from ./include/trace/define_trace.h:102:0,
from ./fs/xfs/scrub/trace.h:988,
from fs/xfs/scrub/trace.c:40:
./fs/xfs/./scrub/trace.h: In function ‘trace_raw_output_xchk_fsgate_class’:
./fs/xfs/scrub/scrub.h:111:28: error: initializer element is not constant
#define XREP_ALREADY_FIXED (1 << 31) /* checking our repair work */
^
Shifting the (signed) value 1 into the sign bit is undefined behavior.
Fix this for all definitions in the file by shifting "1U" instead of
"1".
This was exposed by the first user added in commit 466c525d6d
("xfs: minimize overhead of drain wakeups by using jump labels").
Fixes: 160b5a7845 ("xfs: hoist the already_fixed variable to the scrub context")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The fscounters scrub code doesn't work properly because it cannot
quiesce updates to the percpu counters in the filesystem, hence it
returns false corruption reports. This has been fixed properly in
one of the online repair patchsets that are under review by replacing
the xchk_disable_reaping calls with an exclusive filesystem freeze.
Disabling background gc isn't sufficient to fix the problem.
In other words, scrub doesn't need to call xfs_inodegc_stop, which is
just as well since it wasn't correct to allow scrub to call
xfs_inodegc_start when something else could be calling xfs_inodegc_stop
(e.g. trying to freeze the filesystem).
Neuter the scrubber for now, and remove the xchk_*_reaping functions.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Move the free space bitmap from somewhere in xchk_xattr_buf.buf[] to an
explicit pointer. This is the start of removing the complex overloaded
memory buffer that is the source of weird memory misuse bugs.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Strengthen online scrub's checking even further by enabling us to check
that a range of blocks are owned solely by a given owner.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Make sure that all filesystem metadata blocks and file data blocks are
not also marked as CoW staging extents. The extra checking added here
was inspired by an actual VM host filesystem corruption incident due to
bugs in the CoW handling of 4.x kernels.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
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>
Teach the summary count checker to count the number of free realtime
extents and compare that to the superblock copy.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Memory allocation usage is the same throughout online fsck -- we want
kernel memory, we have to be able to back out if we can't allocate
memory, and we don't want to spray dmesg with memory allocation failure
reports. Standardize the GFP flag usage and document these requirements.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
While scrubbing an allocation group, we don't need to hold the AGFL
buffer as part of the scrub context. All that is necessary to lock an
AG is to hold the AGI and AGF buffers, so fix all the existing users of
the AGFL buffer to grab them only when necessary.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Prior to commit 40b52225e5 ("xfs: remove support for disabling quota
accounting on a mounted file system"), we used the quotaoff mutex to
protect dquot operations against quotaoff trying to pull down dquots as
part of disabling quota.
Now that we only support turning off quota enforcement, the quotaoff
mutex only protects changes in m_qflags/sb_qflags. We don't need it to
protect dquots, which means we can remove it from setqlimits and the
dquot scrub code. While we're at it, fix the function that forces
quotacheck, since it should have been taking the quotaoff mutex.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The scrub feature checks are the last place that the superblock
feature checks are used. Convert them to mount based feature checks.
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>
Now that we always grab an active reference to a perag structure when
dealing with perag metadata, we can remove this unnecessary variable.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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>
While running a new fstest that races a readonly remount with scrub
running in repair mode, I observed the kernel tripping over debugging
assertions in the log quiesce code that were checking that the CIL was
empty. When the sysadmin runs scrub in repair mode, the scrub code
allocates real transactions (with reservations) to change things, but
doesn't increment the superblock writers count to block a readonly
remount attempt while it is running.
We don't require the userspace caller to have a writable file descriptor
to run repairs, so we have to call mnt_want_write_file to obtain freeze
protection and increment the writers count. It's ok to remove the call
to sb_start_write for the dry-run case because commit 8321ddb2fa
removed the behavior where scrub and fsfreeze fight over the buffer LRU.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.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>
Now that we have the ability to track sick metadata in-core, make scrub
and repair update those health assessments after doing work.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Now that we no longer memset the scrub context, we can move the
already_fixed variable into the scrub context's state flags instead of
passing around pointers to separate stack variables.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Combine all the boolean state flags in struct xfs_scrub into a single
unsigned int, because we're going to be adding more state flags soon.
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>
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>
Plumb in the pieces necessary to make the "scrub" subfunction of
the scrub ioctl actually work. This means that we make the IFLAG_REPAIR
flag to the scrub ioctl actually do something, and we add an errortag
knob so that xfstests can force the kernel to rebuild a metadata
structure even if there's nothing wrong with it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Refactor the quota scrubber to take the quotaofflock and grab the quota
inode in the setup function so that we can treat quota in the same
"scrub in the context of this inode" (i.e. sc->ip) manner as we treat
any other inode. We do have to drop the quota inode's ILOCK_EXCL to use
dqiterate, but since dquots have their own individual locks the ILOCK
wasn't helping us anyway.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
While we're scrubbing various btrees, cross-reference the records
with the other metadata.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
During metadata btree scrub, we should cross-reference with the
reference counts.
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>
Cross-reference the inode btrees with the other metadata when we
scrub the filesystem.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
When we're scrubbing various btrees, cross-reference the records with
the bnobt to ensure that we don't also think the space is free.
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>
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>
Add a forgotten check to the AGI verifier, then wire up the scrub
infrastructure to check the AGI contents.
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>
Geert Uytterhoeven