Merge misc updates from Andrew Morton:
"146 patches.
Subsystems affected by this patch series: kthread, ia64, scripts,
ntfs, squashfs, ocfs2, vfs, and mm (slab-generic, slab, kmemleak,
dax, kasan, debug, pagecache, gup, shmem, frontswap, memremap,
memcg, selftests, pagemap, dma, vmalloc, memory-failure, hugetlb,
userfaultfd, vmscan, mempolicy, oom-kill, hugetlbfs, migration, thp,
ksm, page-poison, percpu, rmap, zswap, zram, cleanups, hmm, and
damon)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (146 commits)
mm/damon: hide kernel pointer from tracepoint event
mm/damon/vaddr: hide kernel pointer from damon_va_three_regions() failure log
mm/damon/vaddr: use pr_debug() for damon_va_three_regions() failure logging
mm/damon/dbgfs: remove an unnecessary variable
mm/damon: move the implementation of damon_insert_region to damon.h
mm/damon: add access checking for hugetlb pages
Docs/admin-guide/mm/damon/usage: update for schemes statistics
mm/damon/dbgfs: support all DAMOS stats
Docs/admin-guide/mm/damon/reclaim: document statistics parameters
mm/damon/reclaim: provide reclamation statistics
mm/damon/schemes: account how many times quota limit has exceeded
mm/damon/schemes: account scheme actions that successfully applied
mm/damon: remove a mistakenly added comment for a future feature
Docs/admin-guide/mm/damon/usage: update for kdamond_pid and (mk|rm)_contexts
Docs/admin-guide/mm/damon/usage: mention tracepoint at the beginning
Docs/admin-guide/mm/damon/usage: remove redundant information
Docs/admin-guide/mm/damon/usage: update for scheme quotas and watermarks
mm/damon: convert macro functions to static inline functions
mm/damon: modify damon_rand() macro to static inline function
mm/damon: move damon_rand() definition into damon.h
...
Various places in the kernel - largely in filesystems - respond to a
memory allocation failure by looping around and re-trying. Some of
these cannot conveniently use __GFP_NOFAIL, for reasons such as:
- a GFP_ATOMIC allocation, which __GFP_NOFAIL doesn't work on
- a need to check for the process being signalled between failures
- the possibility that other recovery actions could be performed
- the allocation is quite deep in support code, and passing down an
extra flag to say if __GFP_NOFAIL is wanted would be clumsy.
Many of these currently use congestion_wait() which (in almost all
cases) simply waits the given timeout - congestion isn't tracked for
most devices.
It isn't clear what the best delay is for loops, but it is clear that
the various filesystems shouldn't be responsible for choosing a timeout.
This patch introduces memalloc_retry_wait() with takes on that
responsibility. Code that wants to retry a memory allocation can call
this function passing the GFP flags that were used. It will wait
however is appropriate.
For now, it only considers __GFP_NORETRY and whatever
gfpflags_allow_blocking() tests. If blocking is allowed without
__GFP_NORETRY, then alloc_page either made some reclaim progress, or
waited for a while, before failing. So there is no need for much
further waiting. memalloc_retry_wait() will wait until the current
jiffie ends. If this condition is not met, then alloc_page() won't have
waited much if at all. In that case memalloc_retry_wait() waits about
200ms. This is the delay that most current loops uses.
linux/sched/mm.h needs to be included in some files now,
but linux/backing-dev.h does not.
Link: https://lkml.kernel.org/r/163754371968.13692.1277530886009912421@noble.neil.brown.name
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Prepare for the removal of the block_device from the DAX I/O path by
returning the partition offset from fs_dax_get_by_bdev so that the file
systems have it at hand for use during I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20211129102203.2243509-26-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Hide the DAX device lookup from the xfs_super.c code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20211129102203.2243509-22-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that we've gotten rid of the kmem_zone_t typedef, rename the
variables to _cache since that's what they are.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Remove these typedefs by referencing kmem_cache directly.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
- Fix a potential log livelock on busy filesystems when there's so much
work going on that we can't finish a quotaoff before filling up the log
by removing the ability to disable quota accounting.
- Introduce the ability to use per-CPU data structures in XFS so that
we can do a better job of maintaining CPU locality for certain
operations.
- Defer inode inactivation work to per-CPU lists, which will help us
batch that processing. Deletions of large sparse files will *appear*
to run faster, but all that means is that we've moved the work to the
backend.
- Drop the EXPERIMENTAL warnings from the y2038+ support and the inode
btree counters, since it's been nearly a year and no complaints have
come in.
- Remove more of our bespoke kmem* variants in favor of using the
standard Linux calls.
- Prepare for the addition of log incompat features in upcoming cycles
by actually adding code to support this.
- Small cleanups of the xattr code in preparation for landing support
for full logging of extended attribute updates in a future cycle.
- Replace the various log shutdown state and flag code all over xfs
with a single atomic bit flag.
- Fix a serious log recovery bug where log item replay can be skipped
based on the start lsn of a transaction even though the transaction
commit lsn is the key data point for that by enforcing start lsns to
appear in the log in the same order as commit lsns.
- Enable pipelining in the code that pushes log items to disk.
- Drop ->writepage.
- Fix some bugs in GETFSMAP where the last fsmap record reported for a
device could extend beyond the end of the device, and a separate bug
where query keys for one device could be applied to another.
- Don't let GETFSMAP query functions edit their input parameters.
- Small cleanups to the scrub code's handling of perag structures.
- Small cleanups to the incore inode tree walk code.
- Constify btree function parameters that aren't changed, so that there
will never again be confusion about range query functions changing
their input parameters.
- Standardize the format and names of tracepoint data attributes.
- Clean up all the mount state and feature flags to use wrapped bitset
functions instead of inconsistently open-coded flag checks.
- Fix some confusion between xfs_buf hash table key variable vs. block
number.
- Fix a mis-interaction with iomap where we reported shared delalloc
cow fork extents to iomap, which would cause the iomap unshare
operation to return IO errors unnecessarily.
- Fix DONTCACHE behavior.
-----BEGIN PGP SIGNATURE-----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=HPJr
-----END PGP SIGNATURE-----
Merge tag 'xfs-5.15-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Darrick Wong:
"There's a lot in this cycle.
Starting with bug fixes: To avoid livelocks between the logging code
and the quota code, we've disabled the ability of quotaoff to turn off
quota accounting. (Admins can still disable quota enforcement, but
truly turning off accounting requires a remount.) We've tried to do
this in a careful enough way that there shouldn't be any user visible
effects aside from quotaoff no longer randomly hanging the system.
We've also fixed some bugs in runtime log behavior that could trip up
log recovery if (otherwise unrelated) transactions manage to start and
commit concurrently; some bugs in the GETFSMAP ioctl where we would
incorrectly restrict the range of records output if the two xfs
devices are of different sizes; a bug that resulted in fallocate
funshare failing unnecessarily; and broken behavior in the xfs inode
cache when DONTCACHE is in play.
As for new features: we now batch inode inactivations in percpu
background threads, which sharply decreases frontend thread wait time
when performing file deletions and should improve overall directory
tree deletion times. This eliminates both the problem where closing an
unlinked file (especially on a frozen fs) can stall for a long time,
and should also ease complaints about direct reclaim bogging down on
unlinked file cleanup.
Starting with this release, we've enabled pipelining of the XFS log.
On workloads with high rates of metadata updates to different shards
of the filesystem, multiple threads can be used to format committed
log updates into log checkpoints.
Lastly, with this release, two new features have graduated to
supported status: inode btree counters (for faster mounts), and
support for dates beyond Y2038. Expect these to be enabled by default
in a future release of xfsprogs.
Summary:
- Fix a potential log livelock on busy filesystems when there's so
much work going on that we can't finish a quotaoff before filling
up the log by removing the ability to disable quota accounting.
- Introduce the ability to use per-CPU data structures in XFS so that
we can do a better job of maintaining CPU locality for certain
operations.
- Defer inode inactivation work to per-CPU lists, which will help us
batch that processing. Deletions of large sparse files will
*appear* to run faster, but all that means is that we've moved the
work to the backend.
- Drop the EXPERIMENTAL warnings from the y2038+ support and the
inode btree counters, since it's been nearly a year and no
complaints have come in.
- Remove more of our bespoke kmem* variants in favor of using the
standard Linux calls.
- Prepare for the addition of log incompat features in upcoming
cycles by actually adding code to support this.
- Small cleanups of the xattr code in preparation for landing support
for full logging of extended attribute updates in a future cycle.
- Replace the various log shutdown state and flag code all over xfs
with a single atomic bit flag.
- Fix a serious log recovery bug where log item replay can be skipped
based on the start lsn of a transaction even though the transaction
commit lsn is the key data point for that by enforcing start lsns
to appear in the log in the same order as commit lsns.
- Enable pipelining in the code that pushes log items to disk.
- Drop ->writepage.
- Fix some bugs in GETFSMAP where the last fsmap record reported for
a device could extend beyond the end of the device, and a separate
bug where query keys for one device could be applied to another.
- Don't let GETFSMAP query functions edit their input parameters.
- Small cleanups to the scrub code's handling of perag structures.
- Small cleanups to the incore inode tree walk code.
- Constify btree function parameters that aren't changed, so that
there will never again be confusion about range query functions
changing their input parameters.
- Standardize the format and names of tracepoint data attributes.
- Clean up all the mount state and feature flags to use wrapped
bitset functions instead of inconsistently open-coded flag checks.
- Fix some confusion between xfs_buf hash table key variable vs.
block number.
- Fix a mis-interaction with iomap where we reported shared delalloc
cow fork extents to iomap, which would cause the iomap unshare
operation to return IO errors unnecessarily.
- Fix DONTCACHE behavior"
* tag 'xfs-5.15-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (103 commits)
xfs: fix I_DONTCACHE
xfs: only set IOMAP_F_SHARED when providing a srcmap to a write
xfs: fix perag structure refcounting error when scrub fails
xfs: rename buffer cache index variable b_bn
xfs: convert bp->b_bn references to xfs_buf_daddr()
xfs: introduce xfs_buf_daddr()
xfs: kill xfs_sb_version_has_v3inode()
xfs: introduce xfs_sb_is_v5 helper
xfs: remove unused xfs_sb_version_has wrappers
xfs: convert xfs_sb_version_has checks to use mount features
xfs: convert scrub to use mount-based feature checks
xfs: open code sb verifier feature checks
xfs: convert xfs_fs_geometry to use mount feature checks
xfs: replace XFS_FORCED_SHUTDOWN with xfs_is_shutdown
xfs: convert remaining mount flags to state flags
xfs: convert mount flags to features
xfs: consolidate mount option features in m_features
xfs: replace xfs_sb_version checks with feature flag checks
xfs: reflect sb features in xfs_mount
xfs: rework attr2 feature and mount options
...
To stop external users from using b_bn as the disk address of the
buffer, rename it to b_rhash_key to indicate that it is the buffer
cache index, not the block number of the buffer. Code that needs the
disk address should use xfs_buf_daddr() to obtain it.
Do the rename and clean up any of the remaining internal b_bn users.
Also clean up any remaining b_bn cruft that is now unused.
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>
Introduce a helper function xfs_buf_daddr() to extract the disk
address of the buffer from the struct xfs_buf. This will replace
direct accesses to bp->b_bn and bp->b_maps[0].bm_bn, as well as
the XFS_BUF_ADDR() macro.
This patch introduces the helper function and replaces all uses of
XFS_BUF_ADDR() as this is just a simple sed replacement.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
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>
The remaining mount flags kept in m_flags are actually runtime state
flags. These change dynamically, so they really should be updated
atomically so we don't potentially lose an update due to racing
modifications.
Convert these remaining flags to be stored in m_opstate and use
atomic bitops to set and clear the flags. This also adds a couple of
simple wrappers for common state checks - read only and shutdown.
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>
Since commit 59bb47985c ("mm, sl[aou]b: guarantee natural alignment
for kmalloc(power-of-two)"), the core slab code now guarantees slab
alignment in all situations sufficient for IO purposes (i.e. minimum
of 512 byte alignment of >= 512 byte sized heap allocations) we no
longer need the workaround in the XFS code to provide this
guarantee.
Replace the use of kmem_alloc_io() with kmem_alloc() or
kmem_alloc_large() appropriately, and remove the kmem_alloc_io()
interface altogether.
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>
Just retrieve the bdi from the disk.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210809141744.1203023-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It's a one line wrapper around blkdev_issue_flush(). Just replace it
with direct calls to blkdev_issue_flush().
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
'error' will be initialized, so clean up the redundant initialization.
Cc: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
If we want to use active references to the perag to be able to gate
shrink removing AGs and hence perags safely, we've got a fair bit of
work to do actually use perags in all the places we need to.
There's a lot of code that iterates ag numbers and then
looks up perags from that, often multiple times for the same perag
in the one operation. If we want to use reference counted perags for
access control, then we need to convert all these uses to perag
iterators, not agno iterators.
[Patches 1-4]
The first step of this is consolidating all the perag management -
init, free, get, put, etc into a common location. THis is spread all
over the place right now, so move it all into libxfs/xfs_ag.[ch].
This does expose kernel only bits of the perag to libxfs and hence
userspace, so the structures and code is rearranged to minimise the
number of ifdefs that need to be added to the userspace codebase.
The perag iterator in xfs_icache.c is promoted to a first class API
and expanded to the needs of the code as required.
[Patches 5-10]
These are the first basic perag iterator conversions and changes to
pass the perag down the stack from those iterators where
appropriate. A lot of this is obvious, simple changes, though in
some places we stop passing the perag down the stack because the
code enters into an as yet unconverted subsystem that still uses raw
AGs.
[Patches 11-16]
These replace the agno passed in the btree cursor for per-ag btree
operations with a perag that is passed to the cursor init function.
The cursor takes it's own reference to the perag, and the reference
is dropped when the cursor is deleted. Hence we get reference
coverage for the entire time the cursor is active, even if the code
that initialised the cursor drops it's reference before the cursor
or any of it's children (duplicates) have been deleted.
The first patch adds the perag infrastructure for the cursor, the
next four patches convert a btree cursor at a time, and the last
removes the agno from the cursor once it is unused.
[Patches 17-21]
These patches are a demonstration of the simplifications and
cleanups that come from plumbing the perag through interfaces that
select and then operate on a specific AG. In this case the inode
allocation algorithm does up to three walks across all AGs before it
either allocates an inode or fails. Two of these walks are purely
just to select the AG, and even then it doesn't guarantee inode
allocation success so there's a third walk if the selected AG
allocation fails.
These patches collapse the selection and allocation into a single
loop, simplifies the error handling because xfs_dir_ialloc() always
returns ENOSPC if no AG was selected for inode allocation or we fail
to allocate an inode in any AG, gets rid of xfs_dir_ialloc()
wrapper, converts inode allocation to run entirely from a single
perag instance, and then factors xfs_dialloc() into a much, much
simpler loop which is easy to understand.
Hence we end up with the same inode allocation logic, but it only
needs two complete iterations at worst, makes AG selection and
allocation atomic w.r.t. shrink and chops out out over 100 lines of
code from this hot code path.
[Patch 22]
Converts the unlink path to pass perags through it.
There's more conversion work to be done, but this patchset gets
through a large chunk of it in one hit. Most of the iterators are
converted, so once this is solidified we can move on to converting
these to active references for being able to free perags while the
fs is still active.
-----BEGIN PGP SIGNATURE-----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=YNzW
-----END PGP SIGNATURE-----
Merge tag 'xfs-perag-conv-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs into xfs-5.14-merge2
xfs: initial agnumber -> perag conversions for shrink
If we want to use active references to the perag to be able to gate
shrink removing AGs and hence perags safely, we've got a fair bit of
work to do actually use perags in all the places we need to.
There's a lot of code that iterates ag numbers and then
looks up perags from that, often multiple times for the same perag
in the one operation. If we want to use reference counted perags for
access control, then we need to convert all these uses to perag
iterators, not agno iterators.
[Patches 1-4]
The first step of this is consolidating all the perag management -
init, free, get, put, etc into a common location. THis is spread all
over the place right now, so move it all into libxfs/xfs_ag.[ch].
This does expose kernel only bits of the perag to libxfs and hence
userspace, so the structures and code is rearranged to minimise the
number of ifdefs that need to be added to the userspace codebase.
The perag iterator in xfs_icache.c is promoted to a first class API
and expanded to the needs of the code as required.
[Patches 5-10]
These are the first basic perag iterator conversions and changes to
pass the perag down the stack from those iterators where
appropriate. A lot of this is obvious, simple changes, though in
some places we stop passing the perag down the stack because the
code enters into an as yet unconverted subsystem that still uses raw
AGs.
[Patches 11-16]
These replace the agno passed in the btree cursor for per-ag btree
operations with a perag that is passed to the cursor init function.
The cursor takes it's own reference to the perag, and the reference
is dropped when the cursor is deleted. Hence we get reference
coverage for the entire time the cursor is active, even if the code
that initialised the cursor drops it's reference before the cursor
or any of it's children (duplicates) have been deleted.
The first patch adds the perag infrastructure for the cursor, the
next four patches convert a btree cursor at a time, and the last
removes the agno from the cursor once it is unused.
[Patches 17-21]
These patches are a demonstration of the simplifications and
cleanups that come from plumbing the perag through interfaces that
select and then operate on a specific AG. In this case the inode
allocation algorithm does up to three walks across all AGs before it
either allocates an inode or fails. Two of these walks are purely
just to select the AG, and even then it doesn't guarantee inode
allocation success so there's a third walk if the selected AG
allocation fails.
These patches collapse the selection and allocation into a single
loop, simplifies the error handling because xfs_dir_ialloc() always
returns ENOSPC if no AG was selected for inode allocation or we fail
to allocate an inode in any AG, gets rid of xfs_dir_ialloc()
wrapper, converts inode allocation to run entirely from a single
perag instance, and then factors xfs_dialloc() into a much, much
simpler loop which is easy to understand.
Hence we end up with the same inode allocation logic, but it only
needs two complete iterations at worst, makes AG selection and
allocation atomic w.r.t. shrink and chops out out over 100 lines of
code from this hot code path.
[Patch 22]
Converts the unlink path to pass perags through it.
There's more conversion work to be done, but this patchset gets
through a large chunk of it in one hit. Most of the iterators are
converted, so once this is solidified we can move on to converting
these to active references for being able to free perags while the
fs is still active.
* tag 'xfs-perag-conv-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (23 commits)
xfs: remove xfs_perag_t
xfs: use perag through unlink processing
xfs: clean up and simplify xfs_dialloc()
xfs: inode allocation can use a single perag instance
xfs: get rid of xfs_dir_ialloc()
xfs: collapse AG selection for inode allocation
xfs: simplify xfs_dialloc_select_ag() return values
xfs: remove agno from btree cursor
xfs: use perag for ialloc btree cursors
xfs: convert allocbt cursors to use perags
xfs: convert refcount btree cursor to use perags
xfs: convert rmap btree cursor to using a perag
xfs: add a perag to the btree cursor
xfs: pass perags around in fsmap data dev functions
xfs: push perags through the ag reservation callouts
xfs: pass perags through to the busy extent code
xfs: convert secondary superblock walk to use perags
xfs: convert xfs_iwalk to use perag references
xfs: convert raw ag walks to use for_each_perag
xfs: make for_each_perag... a first class citizen
...
It only has one caller and is now a simple function, so merge it
into the caller.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Use a single goto label for freeing the buffer and returning an
error.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Only used in one place, so just open code the logic in the macro.
Based on a patch from Christoph Hellwig.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Ever since we stopped using the Linux page cache to back XFS buffers
there is no need to take the start sector into account for
calculating the number of pages in a buffer, as the data always
start from the beginning of the buffer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
[dgc: modified to suit this series]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
->b_offset can only be non-zero for _XBF_KMEM backed buffers, so
remove all code dealing with it for page backed buffers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
[dgc: modified to fit this patchset]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
They are AG functions, not superblock functions, so move them to the
appropriate location.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Rather than open coding it just before we call
_xfs_buf_free_pages(). Also, rename the function to
xfs_buf_free_pages() as the leading underscore has no useful
meaning.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Only called from one place now, so merge it into
xfs_buf_alloc_pages(). Because page array allocation is dependent on
bp->b_pages being null, always ensure that when the pages array is
freed we always set bp->b_pages to null.
Also convert the page array to use kmalloc() rather than
kmem_alloc() so we can use the gfp flags we've already calculated
for the allocation context instead of hard coding KM_NOFS semantics.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Because it's more efficient than allocating pages one at a time in a
loop.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Use the newly factored out page allocation code. This adds
automatic buffer zeroing for non-read uncached buffers.
This also allows us to greatly simply the error handling in
xfs_buf_get_uncached(). Because xfs_buf_alloc_pages() cleans up
partial allocation failure, we can just call xfs_buf_free() in all
error cases now to clean up after failures.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Based on a patch from Christoph Hellwig.
This splits out the heap allocation and page allocation portions of
the buffer memory allocation into two separate helper functions.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
list_sort() internally casts the comparison function passed to it
to a different type with constant struct list_head pointers, and
uses this pointer to call the functions, which trips indirect call
Control-Flow Integrity (CFI) checking.
Instead of removing the consts, this change defines the
list_cmp_func_t type and changes the comparison function types of
all list_sort() callers to use const pointers, thus avoiding type
mismatches.
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-10-samitolvanen@google.com
It's often inconvenient to use BIO_MAX_PAGES due to min() requiring the
sign to be the same. Introduce bio_max_segs() and change BIO_MAX_PAGES to
be unsigned to make it easier for the users.
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
xfs_buftarg_drain() is called from xfs_log_quiesce() to ensure the
buffer cache is reclaimed during unmount. xfs_log_quiesce() is also
called from xfs_quiesce_attr(), however, which means that cache
state is completely drained for filesystem freeze and read-only
remount. While technically harmless, this is unnecessarily
heavyweight. Both freeze and read-only mounts allow reads and thus
allow population of the buffer cache. Therefore, the transitional
sequence in either case really only needs to quiesce outstanding
writes to return the filesystem in a generally read-only state.
Additionally, some users have reported that attempts to freeze a
filesystem concurrent with a read-heavy workload causes the freeze
process to stall for a significant amount of time. This occurs
because, as mentioned above, the read workload repopulates the
buffer LRU while the freeze task attempts to drain it.
To improve this situation, replace the drain in xfs_log_quiesce()
with a buffer I/O quiesce and lift the drain into the unmount path.
This removes buffer LRU reclaim from freeze and read-only [re]mount,
but ensures the LRU is still drained before the filesystem unmounts.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
xfs_wait_buftarg() is vaguely named and somewhat overloaded. Its
primary purpose is to reclaim all buffers from the provided buffer
target LRU. In preparation to refactor xfs_wait_buftarg() into
serialization and LRU draining components, rename the function and
associated helpers to something more descriptive. This patch has no
functional changes with the minor exception of renaming a
tracepoint.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Prepare for kernel xfs_buf alignment by getting rid of the
xfs_buf_t typedef from userspace.
[darrick: This patch is a port of a userspace patch removing the
xfs_buf_t typedef in preparation to make the userspace xfs_buf code
behave more like its kernel counterpart.]
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>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Instead of poking deeply into buffer cache internals when re-reading the
superblock during log recovery just generalize _xfs_buf_read and use it
there. Note that we don't have to explicitly set up the ops as they
must be set from the initial read.
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 log recovery I/O completion handler does not substancially differ from
the normal one except for the fact that it:
a) never retries failed writes
b) can have log items that aren't on the AIL
c) never has inode/dquot log items attached and thus don't need to
handle them
Add conditionals for (a) and (b) to the ioend code, while (c) doesn't
need special handling anyway.
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>
Clear the flags at the end of xfs_buf_ioend so that they can be used
during the completion.
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>
Now that all the actual error handling is in a single place,
xfs_buf_ioend_disposition just needs to return true if took ownership of
the buffer, or false if not instead of the tristate. Also move the
error check back in the caller to optimize for the fast path, and give
the function a better fitting name.
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>
Keep all the error handling code together.
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>
Merge xfs_buf_ioerror_retry into its only caller to make the resubmission
flow a little easier to follow.
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>
xfs_buf_ioerror_fail_without_retry is a somewhat weird function in
that it has two trivial checks that decide the return value, while
the rest implements a ratelimited warning. Just lift the two checks
into the caller, and give the remainder a suitable name.
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>
No need to keep a separate helper for this logic.
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 buffer retry state machine logic to xfs_buf.c and call it once
from xfs_ioend instead of duplicating it three times for the three kinds
of buffers.
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 log recovery I/O completion handling entirely into the log
recovery code, and re-arrange the normal I/O completion handler flow
to prepare to lifting more logic into common code in the next commits.
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>
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 kmem_cache_zalloc() directly.
With the exception of xlog_ticket_alloc() which will be dealt on the
next patch for readability.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
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>
All unmarked dirty buffers should be in the AIL and have log items
attached to them. Hence when they are written, we will run a
callback to remove the item from the AIL if appropriate. Now that
we've handled inode and dquot buffers, all remaining calls are to
xfs_buf_iodone() and so we can hard code this rather than use an
indirect call.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Log recovery has it's own buffer write completion handler for
buffers that it directly recovers. Convert these to direct calls by
flagging these buffers as being log recovery buffers. The flag will
get cleared by the log recovery IO completion routine, so it will
never leak out of log recovery.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
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>
dquot buffers always have write IO callbacks, so by marking them
directly we can avoid needing to attach ->b_iodone functions to
them. This avoids an indirect call, and makes future modifications
much simpler.
This is largely a rearrangement of the code at this point - no IO
completion functionality changes at this point, just how the
code is run is modified.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
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>
Inode buffers always have write IO callbacks, so by marking them
directly we can avoid needing to attach ->b_iodone functions to
them. This avoids an indirect call, and makes future modifications
much simpler.
While this is largely a refactor of existing functionality, we
broaden the scope of the flag to beyond where inodes are explicitly
attached because future changes need to know what type of log items
are attached to the buffer. Adding this buffer flag may invoke the
inode iodone callback in cases where it wouldn't have been
previously, but this is not a functional change because the callback
is identical to the normal buffer write iodone callback when inodes
are not attached.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
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>
- Various cleanups to remove dead code, unnecessary conditionals,
asserts, etc.
- Fix a linker warning caused by xfs stuffing '-g' into CFLAGS
redundantly.
- Tighten up our dmesg logging to ensure that everything is prefixed
with 'XFS' for easier grepping.
- Kill a bunch of typedefs.
- Refactor the deferred ops code to reduce indirect function calls.
- Increase type-safety with the deferred ops code.
- Make the DAX mount options a tri-state.
- Fix some error handling problems in the inode flush code and clean up
other inode flush warts.
- Refactor log recovery so that each log item recovery functions now live
with the other log item processing code.
- Fix some SPDX forms.
- Fix quota counter corruption if the fs crashes after running
quotacheck but before any dquots get logged.
- Don't fail metadata verification on zero-entry attr leaf blocks, since
they're just part of the disk format now due to a historic lack of log
atomicity.
- Don't allow SWAPEXT between files with different [ugp]id when quotas
are enabled.
- Refactor inode fork reading and verification to run directly from the
inode-from-disk function. This means that we now actually guarantee
that _iget'ted inodes are totally verified and ready to go.
- Move the incore inode fork format and extent counts to the ifork
structure.
- Scalability improvements by reducing cacheline pingponging in
struct xfs_mount.
- More scalability improvements by removing m_active_trans from the
hot path.
- Fix inode counter update sanity checking to run /only/ on debug
kernels.
- Fix longstanding inconsistency in what error code we return when a
program hits project quota limits (ENOSPC).
- Fix group quota returning the wrong error code when a program hits
group quota limits.
- Fix per-type quota limits and grace periods for group and project
quotas so that they actually work.
- Allow extension of individual grace periods.
- Refactor the non-reclaim inode radix tree walking code to remove a
bunch of stupid little functions and straighten out the
inconsistent naming schemes.
- Fix a bug in speculative preallocation where we measured a new
allocation based on the last extent mapping in the file instead of
looking farther for the last contiguous space allocation.
- Force delalloc writes to unwritten extents. This closes a
stale disk contents exposure vector if the system goes down before
the write completes.
- More lockdep whackamole.
-----BEGIN PGP SIGNATURE-----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=/NYc
-----END PGP SIGNATURE-----
Merge tag 'xfs-5.8-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs updates from Darrick Wong:
"Most of the changes this cycle are refactoring of existing code in
preparation for things landing in the future.
We also fixed various problems and deficiencies in the quota
implementation, and (I hope) the last of the stale read vectors by
forcing write allocations to go through the unwritten state until the
write completes.
Summary:
- Various cleanups to remove dead code, unnecessary conditionals,
asserts, etc.
- Fix a linker warning caused by xfs stuffing '-g' into CFLAGS
redundantly.
- Tighten up our dmesg logging to ensure that everything is prefixed
with 'XFS' for easier grepping.
- Kill a bunch of typedefs.
- Refactor the deferred ops code to reduce indirect function calls.
- Increase type-safety with the deferred ops code.
- Make the DAX mount options a tri-state.
- Fix some error handling problems in the inode flush code and clean
up other inode flush warts.
- Refactor log recovery so that each log item recovery functions now
live with the other log item processing code.
- Fix some SPDX forms.
- Fix quota counter corruption if the fs crashes after running
quotacheck but before any dquots get logged.
- Don't fail metadata verification on zero-entry attr leaf blocks,
since they're just part of the disk format now due to a historic
lack of log atomicity.
- Don't allow SWAPEXT between files with different [ugp]id when
quotas are enabled.
- Refactor inode fork reading and verification to run directly from
the inode-from-disk function. This means that we now actually
guarantee that _iget'ted inodes are totally verified and ready to
go.
- Move the incore inode fork format and extent counts to the ifork
structure.
- Scalability improvements by reducing cacheline pingponging in
struct xfs_mount.
- More scalability improvements by removing m_active_trans from the
hot path.
- Fix inode counter update sanity checking to run /only/ on debug
kernels.
- Fix longstanding inconsistency in what error code we return when a
program hits project quota limits (ENOSPC).
- Fix group quota returning the wrong error code when a program hits
group quota limits.
- Fix per-type quota limits and grace periods for group and project
quotas so that they actually work.
- Allow extension of individual grace periods.
- Refactor the non-reclaim inode radix tree walking code to remove a
bunch of stupid little functions and straighten out the
inconsistent naming schemes.
- Fix a bug in speculative preallocation where we measured a new
allocation based on the last extent mapping in the file instead of
looking farther for the last contiguous space allocation.
- Force delalloc writes to unwritten extents. This closes a stale
disk contents exposure vector if the system goes down before the
write completes.
- More lockdep whackamole"
* tag 'xfs-5.8-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (129 commits)
xfs: more lockdep whackamole with kmem_alloc*
xfs: force writes to delalloc regions to unwritten
xfs: refactor xfs_iomap_prealloc_size
xfs: measure all contiguous previous extents for prealloc size
xfs: don't fail unwritten extent conversion on writeback due to edquot
xfs: rearrange xfs_inode_walk_ag parameters
xfs: straighten out all the naming around incore inode tree walks
xfs: move xfs_inode_ag_iterator to be closer to the perag walking code
xfs: use bool for done in xfs_inode_ag_walk
xfs: fix inode ag walk predicate function return values
xfs: refactor eofb matching into a single helper
xfs: remove __xfs_icache_free_eofblocks
xfs: remove flags argument from xfs_inode_ag_walk
xfs: remove xfs_inode_ag_iterator_flags
xfs: remove unused xfs_inode_ag_iterator function
xfs: replace open-coded XFS_ICI_NO_TAG
xfs: move eofblocks conversion function to xfs_ioctl.c
xfs: allow individual quota grace period extension
xfs: per-type quota timers and warn limits
xfs: switch xfs_get_defquota to take explicit type
...
This is always PAGE_KERNEL - for long term mappings with other properties
vmap should be used.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-19-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The random buffer write failure errortag patch introduced a local
mount pointer variable for the test macro, but the macro is compiled
out on !DEBUG kernels. This results in an unused variable warning.
Access the mount structure through the buffer pointer and remove the
local mount pointer to address the warning.
Fixes: 7376d74547 ("xfs: random buffer write failure errortag")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Introduce an error tag to randomly fail async buffer writes. This is
primarily to facilitate testing of the XFS error configuration
mechanism.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
At unmount time, XFS emits an alert for every in-core buffer that
might have undergone a write error. In practice this behavior is
probably reasonable given that the filesystem is likely short lived
once I/O errors begin to occur consistently. Under certain test or
otherwise expected error conditions, this can spam the logs and slow
down the unmount.
Now that we have a ratelimit mechanism specifically for buffer
alerts, reuse it for the per-buffer alerts in xfs_wait_buftarg().
Also lift the final repair message out of the loop so it always
prints and assert that the metadata error handling code has shut
down the fs.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
XFS has some inconsistent log message rate limiting with respect to
buffer alerts. The metadata I/O error notification uses the generic
ratelimited alert, the buffer push code uses a custom rate limit and
the similar quiesce time failure checks are not rate limited at all
(when they should be).
The custom rate limit defined in the buf item code is specifically
crafted for buffer alerts. It is more aggressive than generic rate
limiting code because it must accommodate a high frequency of I/O
error events in a relative short timeframe.
Factor out the custom rate limit state from the buf item code into a
per-buftarg rate limit so various alerts are limited based on the
target. Define a buffer alert helper function and use it for the
buffer alerts that are already ratelimited.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The buffer write failure flag is intended to control the internal
write retry that XFS has historically implemented to help mitigate
the severity of transient I/O errors. The flag is set when a buffer
is resubmitted from the I/O completion path due to a previous
failure. It is checked on subsequent I/O completions to skip the
internal retry and fall through to the higher level configurable
error handling mechanism. The flag is cleared in the synchronous and
delwri submission paths and also checked in various places to log
write failure messages.
There are a couple minor problems with the current usage of this
flag. One is that we issue an internal retry after every submission
from xfsaild due to how delwri submission clears the flag. This
results in double the expected or configured number of write
attempts when under sustained failures. Another more subtle issue is
that the flag is never cleared on successful I/O completion. This
can cause xfs_wait_buftarg() to suggest that dirty buffers are being
thrown away due to the existence of the flag, when the reality is
that the flag might still be set because the write succeeded on the
retry.
Clear the write failure flag on successful I/O completion to address
both of these problems. This means that the internal retry attempt
occurs once since the last time a buffer write failed and that
various other contexts only see the flag set when the immediately
previous write attempt has failed.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
We use the same buffer I/O failure code in a few different places.
It's not much code, but it's not necessarily self-explanatory.
Factor it into a helper and document it in one place.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The buffer cache shrinker frees more than just the xfs_buf slab
objects - it also frees the pages attached to the buffers. Make sure
the memory reclaim code accounts for this memory being freed
correctly, similar to how the inode shrinker accounts for pages
freed from the page cache due to mapping invalidation.
We also need to make sure that the mm subsystem knows these are
reclaimable objects. We provide the memory reclaim subsystem with a
a shrinker to reclaim xfs_bufs, so we should really mark the slab
that way.
We also have a lot of xfs_bufs in a busy system, spread them around
like we do inodes.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
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>
Add a xfs_failaddr_t parameter to this function so that callers can
potentially pass in (and therefore report) the exact point in the code
where we decided that a metadata buffer was corrupt. This enables us to
wire it up to checking functions that have to run outside of verifiers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a helper function to get rid of buffers that we have decided are
corrupt after the verifiers have run. This function is intended to
handle metadata checks that can't happen in the verifiers, such as
inter-block relationship checking. Note that we now mark the buffer
stale so that it will not end up on any LRU and will be purged on
release.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Use printk_ratelimit() to limit the amount of messages printed from
xfs_buf_ioerror_alert. Without that a failing device causes a large
number of errors that doesn't really help debugging the underling
issue.
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>
If xfs_buf_get_map can't allocate enough memory for the buffer it's
trying to create, it'll cough up an error about not being able to
allocate "pagesn". That's not particularly helpful (and if we're really
out of memory the message is very spammy) so change the message to tell
us how many pages were actually requested, and ratelimit it too.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Instead of passing __func__ to the error reporting function, let's use
the return address builtins so that the messages actually tell you which
higher level function called the buffer functions. This was previously
true for the xfs_buf_read callers, but not for the xfs_trans_read_buf
callers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Convert xfs_buf_get_uncached() to return numeric error codes like most
everywhere else in xfs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Convert xfs_buf_read_map() to return numeric error codes like most
everywhere else in xfs. This involves moving the open-coded logic that
reports metadata IO read / corruption errors and stales the buffer into
xfs_buf_read_map so that the logic is all in one place.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Convert xfs_buf_get_map() to return numeric error codes like most
everywhere else in xfs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Convert _xfs_buf_alloc() to return numeric error codes like most
everywhere else in xfs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
We can remove it now, without needing to rework the KM_ flags.
Use kmem_cache_free() directly.
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Use kmem_cache_destroy directly
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Remove kmem_zone_init() and kmem_zone_init_flags() together with their
specific KM_* to SLAB_* flag wrappers.
Use kmem_cache_create() directly.
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Just fix the typos checkpatch notices...
Signed-off-by: Joe Perches <joe@perches.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>
Stop using the deprecated bio_set_op_attrs helper, and use a single
argument to xfs_buf_ioapply_map for the operation and flags.
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>
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>
Guarantee zeroed memory buffers for cases where potential memory
leak to disk can occur. In these cases, kmem_alloc is used and
doesn't zero the buffer, opening the possibility of information
leakage to disk.
Use existing infrastucture (xfs_buf_allocate_memory) to obtain
the already zeroed buffer from kernel memory.
This solution avoids the performance issue that would occur if a
wholesale change to replace kmem_alloc with kmem_zalloc was done.
Signed-off-by: Bill O'Donnell <billodo@redhat.com>
[darrick: fix bitwise complaint about kmflag_mask]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Memory we use to submit for IO needs strict alignment to the
underlying driver contraints. Worst case, this is 512 bytes. Given
that all allocations for IO are always a power of 2 multiple of 512
bytes, the kernel heap provides natural alignment for objects of
these sizes and that suffices.
Until, of course, memory debugging of some kind is turned on (e.g.
red zones, poisoning, KASAN) and then the alignment of the heap
objects is thrown out the window. Then we get weird IO errors and
data corruption problems because drivers don't validate alignment
and do the wrong thing when passed unaligned memory buffers in bios.
TO fix this, introduce kmem_alloc_io(), which will guaranteeat least
512 byte alignment of buffers for IO, even if memory debugging
options are turned on. It is assumed that the minimum allocation
size will be 512 bytes, and that sizes will be power of 2 mulitples
of 512 bytes.
Use this everywhere we allocate buffers for IO.
This no longer fails with log recovery errors when KASAN is enabled
due to the brd driver not handling unaligned memory buffers:
# mkfs.xfs -f /dev/ram0 ; mount /dev/ram0 /mnt/test
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP,
we can remove KM_NOSLEEP and replace KM_SLEEP with 0.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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>
We need to derive the mount pointer from a buffer in a lot of place.
Add a direct pointer to short cut the pointer chasing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This field is now always idential to b_length.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
Now that the log code uses bios directly we can drop various special
cases in the buffer cache code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
Rename the function to kmem_to_page and move it to kmem.h together
with our kmem_large allocator that may either return kmalloced or
vmalloc pages.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
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>
xfs_buf_zero is the only caller of xfs_buf_iomove. Remove support
for copying from or to the buffer in xfs_buf_iomove and merge the
two functions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
Create a separate magic16 check function so that we don't run afoul of
static checkers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The inode btree verifier code is shared between the inode btree and
free inode btree because the underlying metadata formats are
essentially equivalent. A side effect of this is that the verifier
cannot determine whether a particular btree block should have an
inobt or finobt magic value.
This logic allows an unfortunate xfs_repair bug to escape detection
where certain level > 0 nodes of the finobt are stamped with inobt
magic by xfs_repair finobt reconstruction. This is fortunately not a
severe problem since the inode btree magic values do not contribute
to any changes in kernel behavior, but we do need a means to detect
and prevent this problem in the future.
Add a field to xfs_buf_ops to store the v4 and v5 superblock magic
values expected by a particular verifier. Add a helper to check an
on-disk magic value against the value expected by the verifier. Call
the helper from the shared [f]inobt verifier code for magic value
verification. This ensures that the inode btree blocks each have the
appropriate magic value based on specific tree type and superblock
version.
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>
Improve the documentation around xfs_buf_ensure_ops, which is the
function that is responsible for cleaning up the b_ops state of buffers
that go through xrep_findroot_block but don't match anything. Rename
the function to xfs_buf_reverify.
[darrick: this started off as bfoster mods of a previous patch of mine,
but the renaming part is now this separate patch.]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
In xrep_findroot_block, we work out the btree type and correctness of a
given block by calling different btree verifiers on root block
candidates. However, we leave the NULL b_ops while ->verify_read
validates the block, which means that if the verifier calls
xfs_buf_verifier_error it'll crash on the null b_ops. Fix it to set
b_ops before calling the verifier and unsetting it if the verifier
fails.
Furthermore, improve the documentation around xfs_buf_ensure_ops, which
is the function that is responsible for cleaning up the b_ops state of
buffers that go through xrep_findroot_block but don't match anything.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
As of commit e339dd8d8b ("xfs: use sync buffer I/O for sync delwri
queue submission"), the delwri submission code uses sync buffer I/O
for sync delwri I/O. Instead of waiting on async I/O to unlock the
buffer, it uses the underlying sync I/O completion mechanism.
If delwri buffer submission fails due to a shutdown scenario, an
error is set on the buffer and buffer completion never occurs. This
can cause xfs_buf_delwri_submit() to deadlock waiting on a
completion event.
We could check the error state before waiting on such buffers, but
that doesn't serialize against the case of an error set via a racing
I/O completion. Instead, invoke I/O completion in the shutdown case
regardless of buffer I/O type.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-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>
Drop LIST_HEAD where the variable it declares has never
been used.
The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
identifier x;
@@
- LIST_HEAD(x);
... when != x
// </smpl>
Fixes: 26f1fe858f ("xfs: reduce lock hold times in buffer writeback")
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
In the typical unmount case, the AIL is forced out by the unmount
sequence before the xfsaild task is stopped. Since AIL items are
removed on writeback completion, this means that the AIL
->ail_buf_list delwri queue has been drained. This is not always
true in the shutdown case, however.
It's possible for buffers to sit on a delwri queue for a period of
time across submission attempts if said items are locked or have
been relogged and pinned since first added to the queue. If the
attempt to log such an item results in a log I/O error, the error
processing can shutdown the fs, remove the item from the AIL, stale
the buffer (dropping the LRU reference) and clear its delwri queue
state. The latter bit means the buffer will be released from a
delwri queue on the next submission attempt, but this might never
occur if the filesystem has shutdown and the AIL is empty.
This means that such buffers are held indefinitely by the AIL delwri
queue across destruction of the AIL. Aside from being a memory leak,
these buffers can also hold references to in-core perag structures.
The latter problem manifests as a generic/475 failure, reproducing
the following asserts at unmount time:
XFS: Assertion failed: atomic_read(&pag->pag_ref) == 0,
file: fs/xfs/xfs_mount.c, line: 151
XFS: Assertion failed: atomic_read(&pag->pag_ref) == 0,
file: fs/xfs/xfs_mount.c, line: 132
To prevent this problem, clear the AIL delwri queue as a final step
before xfsaild() exit. The !empty state should never occur in the
normal case, so add an assert to catch unexpected problems going
forward.
[dgc: add comment explaining need for xfs_buf_delwri_cancel() after
calling xfs_buf_delwri_submit_nowait().]
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When looking at a 4.18 based KASAN use after free report, I noticed
that racing xfs_buf_rele() may race on dropping the last reference
to the buffer and taking the buffer lock. This was the symptom
displayed by the KASAN report, but the actual issue that was
reported had already been fixed in 4.19-rc1 by commit e339dd8d8b
("xfs: use sync buffer I/O for sync delwri queue submission").
Despite this, I think there is still an issue with xfs_buf_rele()
in this code:
release = atomic_dec_and_lock(&bp->b_hold, &pag->pag_buf_lock);
spin_lock(&bp->b_lock);
if (!release) {
.....
If two threads race on the b_lock after both dropping a reference
and one getting dropping the last reference so release = true, we
end up with:
CPU 0 CPU 1
atomic_dec_and_lock()
atomic_dec_and_lock()
spin_lock(&bp->b_lock)
spin_lock(&bp->b_lock)
<spins>
<release = true bp->b_lru_ref = 0>
<remove from lists>
freebuf = true
spin_unlock(&bp->b_lock)
xfs_buf_free(bp)
<gets lock, reading and writing freed memory>
<accesses freed memory>
spin_unlock(&bp->b_lock) <reads/writes freed memory>
IOWs, we can't safely take bp->b_lock after dropping the hold
reference because the buffer may go away at any time after we
drop that reference. However, this can be fixed simply by taking the
bp->b_lock before we drop the reference.
It is safe to nest the pag_buf_lock inside bp->b_lock as the
pag_buf_lock is only used to serialise against lookup in
xfs_buf_find() and no other locks are held over or under the
pag_buf_lock there. Make this clear by documenting the buffer lock
orders at the top of the file.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com
Signed-off-by: Dave Chinner <david@fromorbit.com>
If a caller supplies buffer ops when trying to read a buffer and the
buffer doesn't already have buf ops assigned, ensure that the ops are
assigned to the buffer and the verifier is run on that buffer.
Note that current XFS code is careful to assign buffer ops after a
xfs_{trans_,}buf_read call in which ops were not supplied. However, we
should apply ops defensively in case there is ever a coding mistake; and
an upcoming repair patch will need to be able to read a buffer without
assigning buf ops.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The old lock tracking infrastructure in xfs using the b_last_holder
field seems to only be useful if you can get into the system with a
debugger; it seems that the existing tracepoints would be the way to
go these days, and this old infrastructure can be removed.
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>
Now that there is only one caller, fold the common submission helper
into __xfs_buf_submit().
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The buffer I/O submission path consists of separate function calls
per type. The buffer I/O type is already controlled via buffer
state (XBF_ASYNC), however, so there is no real need for separate
submission functions.
Combine the buffer submission functions into a single function that
processes the buffer appropriately based on XBF_ASYNC. Retain an
internal helper with a conditional wait parameter to continue to
support batched !XBF_ASYNC submission/completion required by delwri
queues.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
If a delwri queue occurs of a buffer that sits on a delwri queue
wait list, the queue sets _XBF_DELWRI_Q without changing the state
of ->b_list. This occurs, for example, if another thread beats the
current delwri waiter thread to the buffer lock after I/O
completion. Once the waiter acquires the lock, it removes the buffer
from the wait list and leaves a buffer with _XBF_DELWRI_Q set but
not populated on a list. This results in a lost buffer submission
and in turn can result in assert failures due to _XBF_DELWRI_Q being
set on buffer reclaim or filesystem lockups if the buffer happens to
cover an item in the AIL.
This problem has been reproduced by repeated iterations of xfs/305
on high CPU count (28xcpu) systems with limited memory (~1GB). Dirty
dquot reclaim races with an xfsaild push of a separate dquot backed
by the same buffer such that the buffer sits on the reclaim wait
list at the time xfsaild attempts to queue it. Since the latter
dquot has been flush locked but the underlying buffer not submitted
for I/O, the dquot pins the AIL and causes the filesystem to
livelock.
This race is essentially made possible by the buffer lock cycle
involved with waiting on a synchronous delwri queue submission.
Close the race by using synchronous buffer I/O for respective delwri
queue submission. This means the buffer remains locked across the
I/O and so is inaccessible from other contexts while in the
intermediate wait list state. The sync buffer I/O wait mechanism is
factored into a helper such that sync delwri buffer submission and
serialization are batched operations.
Designed-by: Dave Chinner <dchinner@redhat.com>
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>
Sync and async buffer submission both do generally similar things
with a couple odd exceptions. Refactor the core buffer submission
code into a common helper to isolate buffer submission from
completion handling of synchronous buffer I/O.
This patch does not change behavior. It is a step towards support
for using synchronous buffer I/O via synchronous delwri queue
submission.
Designed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
xfs_reflink_convert_cow() manipulates the incore extent list
in GFP_KERNEL context in the IO submission path whilst holding
locked pages under writeback. This is a memory reclaim deadlock
vector. This code is not in a transaction, so any memory allocations
it makes aren't protected via the memalloc_nofs_save() context that
transactions carry.
Hence we need to run this call under memalloc_nofs_save() context to
prevent potential memory allocations from being run as GFP_KERNEL
and deadlocking.
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
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>
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>
