Commit graph

295 commits

Author SHA1 Message Date
Brian Foster
8321ddb2fa xfs: don't drain buffer lru on freeze and read-only remount
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>
2021-01-22 16:54:50 -08:00
Brian Foster
10fb9ac125 xfs: rename xfs_wait_buftarg() to xfs_buftarg_drain()
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>
2021-01-22 16:54:50 -08:00
Dave Chinner
e82226138b xfs: remove xfs_buf_t typedef
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>
2020-12-16 16:07:34 -08:00
Christoph Hellwig
26e328759b xfs: reuse _xfs_buf_read for re-reading the superblock
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>
2020-09-15 20:52:39 -07:00
Christoph Hellwig
22c10589a1 xfs: remove xlog_recover_iodone
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>
2020-09-15 20:52:39 -07:00
Christoph Hellwig
55b7d7115f xfs: clear the read/write flags later in xfs_buf_ioend
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>
2020-09-15 20:52:39 -07:00
Christoph Hellwig
70796c6b74 xfs: simplify the xfs_buf_ioend_disposition calling convention
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>
2020-09-15 20:52:38 -07:00
Christoph Hellwig
844c9358df xfs: lift the XBF_IOEND_FAIL handling into xfs_buf_ioend_disposition
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>
2020-09-15 20:52:38 -07:00
Christoph Hellwig
3cc498845a xfs: remove xfs_buf_ioerror_retry
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>
2020-09-15 20:52:38 -07:00
Christoph Hellwig
f58d0ea956 xfs: refactor xfs_buf_ioerror_fail_without_retry
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>
2020-09-15 20:52:38 -07:00
Christoph Hellwig
6a7584b1d8 xfs: fold xfs_buf_ioend_finish into xfs_ioend
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>
2020-09-15 20:52:38 -07:00
Christoph Hellwig
664ffb8a42 xfs: move the buffer retry logic to xfs_buf.c
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>
2020-09-15 20:52:38 -07:00
Christoph Hellwig
23fb5a93c2 xfs: refactor xfs_buf_ioend
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>
2020-09-15 20:52:38 -07:00
Christoph Hellwig
76b2d32346 xfs: mark xfs_buf_ioend static
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>
2020-09-15 20:52:38 -07:00
Carlos Maiolino
32a2b11f46 xfs: Remove kmem_zone_zalloc() usage
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>
2020-07-28 20:24:14 -07:00
Dave Chinner
b01d1461ae xfs: call xfs_buf_iodone directly
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>
2020-07-06 10:46:58 -07:00
Dave Chinner
9fe5c77cbe xfs: mark log recovery buffers for completion
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>
2020-07-06 10:46:58 -07:00
Dave Chinner
0c7e5afbea xfs: mark dquot buffers in cache
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>
2020-07-06 10:46:58 -07:00
Dave Chinner
f593bf144c xfs: mark inode buffers in cache
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>
2020-07-06 10:46:58 -07:00
Linus Torvalds
16d91548d1 New code for 5.8:
- 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.
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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
  ...
2020-06-02 19:21:40 -07:00
Christoph Hellwig
d4efd79a81 mm: remove the prot argument from vm_map_ram
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>
2020-06-02 10:59:11 -07:00
Brian Foster
43dc0aa84e xfs: fix unused variable warning in buffer completion on !DEBUG
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>
2020-05-08 08:50:52 -07:00
Brian Foster
7376d74547 xfs: random buffer write failure errortag
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>
2020-05-07 08:27:48 -07:00
Brian Foster
61948b6fb2 xfs: ratelimit unmount time per-buffer I/O error alert
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>
2020-05-07 08:27:46 -07:00
Brian Foster
f9bccfcc3b xfs: refactor ratelimited buffer error messages into helper
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>
2020-05-07 08:27:46 -07:00
Brian Foster
b6983e80b0 xfs: reset buffer write failure state on successful completion
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>
2020-05-07 08:27:46 -07:00
Brian Foster
54b3b1f619 xfs: factor out buffer I/O failure code
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>
2020-05-07 08:27:45 -07:00
Dave Chinner
12eba65b28 xfs: Improve metadata buffer reclaim accountability
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>
2020-03-27 08:32:54 -07:00
Darrick J. Wong
e83cf875d6 xfs: xfs_buf_corruption_error should take __this_address
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>
2020-03-12 07:58:12 -07:00
Darrick J. Wong
8d57c21600 xfs: add a function to deal with corrupt buffers post-verifiers
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>
2020-03-12 07:58:12 -07:00
Christoph Hellwig
13b1f811b1 xfs: ratelimit xfs_buf_ioerror_alert messages
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>
2020-03-02 20:55:51 -08:00
Darrick J. Wong
93baa55af1 xfs: improve error message when we can't allocate memory for xfs_buf
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>
2020-03-02 20:55:50 -08:00
Darrick J. Wong
cdbcf82b86 xfs: fix xfs_buf_ioerror_alert location reporting
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>
2020-01-26 14:32:27 -08:00
Darrick J. Wong
2842b6db3d xfs: make xfs_buf_get_uncached return an error code
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>
2020-01-26 14:32:26 -08:00
Darrick J. Wong
4ed8e27b4f xfs: make xfs_buf_read_map return an error code
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>
2020-01-26 14:32:26 -08:00
Darrick J. Wong
3848b5f670 xfs: make xfs_buf_get_map return an error code
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>
2020-01-26 14:32:25 -08:00
Darrick J. Wong
32dff5e5d1 xfs: make xfs_buf_alloc return an error code
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>
2020-01-26 14:32:25 -08:00
Carlos Maiolino
377bcd5f3b xfs: Remove kmem_zone_free() wrapper
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>
2019-11-18 08:40:44 -08:00
Carlos Maiolino
aaf54eb8bc xfs: Remove kmem_zone_destroy() wrapper
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>
2019-11-18 08:40:44 -08:00
Carlos Maiolino
b1231760e4 xfs: Remove slab init wrappers
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>
2019-11-18 08:40:43 -08:00
Joe Perches
cf085a1b5d xfs: Correct comment tyops -> typos
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>
2019-11-10 10:21:57 -08:00
Christoph Hellwig
2123ef8510 xfs: simplify setting bio flags
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>
2019-10-29 09:50:12 -07:00
Christoph Hellwig
25a409572b xfs: mark xfs_buf_free static
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>
2019-10-28 08:37:54 -07:00
Bill O'Donnell
3219e8cf0d xfs: assure zeroed memory buffers for certain kmem allocations
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>
2019-10-06 15:39:06 -07:00
Denis Efremov
14ed868807 xfs: remove unlikely() from WARN_ON() condition
"unlikely(WARN_ON(x))" is excessive. WARN_ON() already uses unlikely()
internally.

Link: http://lkml.kernel.org/r/20190829165025.15750-7-efremov@linux.com
Signed-off-by: Denis Efremov <efremov@linux.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-26 10:10:30 -07:00
Dave Chinner
f8f9ee4794 xfs: add kmem_alloc_io()
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>
2019-08-26 17:43:15 -07:00
Tetsuo Handa
707e0ddaf6 fs: xfs: Remove KM_NOSLEEP and KM_SLEEP.
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>
2019-08-26 12:06:22 -07:00
Eric Sandeen
250d4b4c40 xfs: remove unused header files
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>
2019-06-28 19:30:43 -07:00
Christoph Hellwig
dbd329f1e4 xfs: add struct xfs_mount pointer to struct xfs_buf
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>
2019-06-28 19:27:29 -07:00
Christoph Hellwig
8124b9b601 xfs: remove the b_io_length field in struct xfs_buf
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>
2019-06-28 19:27:28 -07:00
Christoph Hellwig
0564501ff5 xfs: remove unused buffer cache APIs
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>
2019-06-28 19:27:27 -07:00
Christoph Hellwig
72945d86dd xfs: make mem_to_page available outside of xfs_buf.c
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>
2019-06-28 19:27:19 -07:00
Darrick J. Wong
5467b34bd1 xfs: move xfs_ino_geometry to xfs_shared.h
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>
2019-06-28 19:25:35 -07:00
Christoph Hellwig
f9a196ee5a xfs: merge xfs_buf_zero and xfs_buf_iomove
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>
2019-06-12 08:59:59 -07:00
Darrick J. Wong
15baadf72c xfs: fix xfs_buf magic number endian checks
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>
2019-02-18 09:38:41 -08:00
Brian Foster
8473fee340 xfs: distinguish between inobt and finobt magic values
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>
2019-02-11 16:07:01 -08:00
Brian Foster
75d0230314 xfs: clarify documentation for the function to reverify buffers
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>
2019-02-11 16:07:01 -08:00
Darrick J. Wong
add46b3b02 xfs: set buffer ops when repair probes for btree type
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>
2019-02-03 14:03:59 -08:00
Brian Foster
465fa17f4a xfs: end sync buffer I/O properly on shutdown error
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>
2019-02-03 14:03:06 -08:00
Julia Lawall
89be677b6b xfs: xfs_buf: drop useless LIST_HEAD
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>
2018-12-29 10:47:34 -08:00
Brian Foster
efc3289cf8 xfs: clear ail delwri queued bufs on unmount of shutdown fs
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>
2018-10-18 17:21:49 +11:00
Dave Chinner
37fd167824 xfs: fix use-after-free race in xfs_buf_rele
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>
2018-10-18 17:21:29 +11:00
Darrick J. Wong
1aff5696f3 xfs: always assign buffer verifiers when one is provided
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>
2018-10-18 17:20:30 +11:00
Eric Sandeen
fa6c668d80 xfs: remove b_last_holder & associated macros
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>
2018-08-12 08:37:31 -07:00
Brian Foster
bb00b6f1e2 xfs: kill __xfs_buf_submit_common()
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>
2018-07-11 22:26:35 -07:00
Brian Foster
6af88cda00 xfs: combine [a]sync buffer submission apis
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>
2018-07-11 22:26:35 -07:00
Brian Foster
e339dd8d8b xfs: use sync buffer I/O for sync delwri queue submission
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>
2018-07-11 22:26:34 -07:00
Brian Foster
eaebb515f1 xfs: refactor buffer submission into a common helper
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>
2018-07-11 22:26:34 -07:00
Dave Chinner
4a2d01b076 xfs: xfs_reflink_convert_cow() memory allocation deadlock
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>
2018-06-08 10:07:51 -07:00
Dave Chinner
0b61f8a407 xfs: convert to SPDX license tags
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>
2018-06-06 14:17:53 -07:00
Dave Chinner
b027d4c97b xfs: don't retry xfs_buf_find on XBF_TRYLOCK failure
When looking at an event trace recently, I noticed that non-blocking
buffer lookup attempts would fail on cached locked buffers and then
run the slow cache-miss path. This means we are doing an xfs_buf
allocation, lookup and free unnecessarily every time we avoid
blocking on a locked buffer.

Fix this by changing _xfs_buf_find() to return an error status to
the caller to indicate that we failed the lock attempt rather than
just returning a NULL. This allows the higher level code to
discriminate between a cache miss and an cache hit that we failed to
lock.

This also allows us to return a -EFSCORRUPTED state if we are asked
to look up a block number outside the range of the filesystem in
_xfs_buf_find(), which moves us one step closer to being able to
handle such errors in a more graceful manner at the higher levels.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-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>
2018-05-09 10:04:00 -07:00
Dave Chinner
8925a3dc47 xfs: make xfs_buf_incore out of line
Move xfs_buf_incore out of line and make it the only way to look up
a buffer in the buffer cache from outside the buffer cache. Convert
the external users of _xfs_buf_find() to xfs_buf_incore() and make
_xfs_buf_find() static.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: actually rename xfs_incore -> xfs_buf_incore]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-09 10:04:00 -07:00
Eric Sandeen
a1f69417c6 xfs: non-scrub - remove unused function parameters
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>
2018-04-09 10:23:42 -07:00
Vratislav Bendel
19957a1816 xfs: Correctly invert xfs_buftarg LRU isolation logic
Due to an inverted logic mistake in xfs_buftarg_isolate()
the xfs_buffers with zero b_lru_ref will take another trip
around LRU, while isolating buffers with non-zero b_lru_ref.

Additionally those isolated buffers end up right back on the LRU
once they are released, because b_lru_ref remains elevated.

Fix that circuitous route by leaving them on the LRU
as originally intended.

Signed-off-by: Vratislav Bendel <vbendel@redhat.com>
Reviewed-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>
2018-03-11 20:27:56 -07:00
Carlos Maiolino
643c8c05e7 Use list_head infra-structure for buffer's log items list
Now that buffer's b_fspriv has been split, just replace the current
singly linked list of xfs_log_items, by the list_head infrastructure.

Also, remove the xfs_log_item argument from xfs_buf_resubmit_failed_buffers(),
there is no need for this argument, once the log items can be walked
through the list_head in the buffer.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: minor style cleanups]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-01-29 07:27:22 -08:00
Darrick J. Wong
c219b01579 xfs: clarify units in the failed metadata io message
If a metadata IO error happens, we report the location of the failed IO
request in units of daddrs.  However, the printk message misleads people
into thinking that the units are fs blocks, so fix the reported units.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-09 15:18:07 -08:00
Darrick J. Wong
9c712a1346 xfs: dump the first 128 bytes of any corrupt buffer
Increase the corrupt buffer dump to the first 128 bytes since v5
filesystems have larger block headers than before.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-08 10:54:47 -08:00
Darrick J. Wong
31ca03c92c xfs: refactor xfs_verifier_error and xfs_buf_ioerror
Since all verification errors also mark the buffer as having an error,
we can combine these two calls.  Later we'll add a xfs_failaddr_t
parameter to promote the idea of reporting corruption errors and the
address of the failing check to enable better debugging reports.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-08 10:54:45 -08:00
Michal Hocko
d210a9874b xfs: fortify xfs_alloc_buftarg error handling
percpu_counter_init failure path doesn't clean up &btp->bt_lru list.
Call list_lru_destroy in that error path. Similarly register_shrinker
error path is not handled.

While it is unlikely to trigger these error path, it is not impossible
especially the later might fail with large NUMAs.  Let's handle the
failure to make the code more robust.

Noticed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-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>
2017-11-28 08:57:11 -08:00
Darrick J. Wong
e9e899a2a8 xfs: move error injection tags into their own file
Move the error injection tag names into a libxfs header so that we can
share it between kernel and userspace.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2017-11-01 15:03:16 -07:00
Brian Foster
4eadcf9a41 xfs: fix unused variable warning in xfs_buf_set_ref()
Fix an unused variable warning on non-DEBUG builds introduced by
commit 7561d27e90 ("xfs: buffer lru reference count error injection
tag").

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>
2017-10-27 09:20:31 -07:00
Brian Foster
7561d27e90 xfs: buffer lru reference count error injection tag
XFS uses a fixed reference count for certain types of buffers in the
internal LRU cache. These reference counts dictate how aggressively
certain buffers are reclaimed vs. others. While the reference counts
implements priority across different buffer types, all buffers
(other than uncached buffers) are typically cached for at least one
reclaim cycle.

We've had at least one bug recently that has been hidden by a
released buffer sitting around in the LRU. Users hitting the problem
were able to reproduce under enough memory pressure to cause
aggressive reclaim in a particular window of time.

To support future xfstests cases, add an error injection tag to
hardcode the buffer reference count to zero. When enabled, this
bypasses caching of associated buffers and facilitates test cases
that depend on this behavior.

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>
2017-10-26 15:38:23 -07:00
Colin Ian King
60915f83cd xfs: remove redundant re-initialization of total_nr_pages
Variable total_nr_pages is being initialized and then updated with
the same value, this latter assignment is redundant and can be
removed.  Cleans up clang build warning:

Value stored to 'total_nr_pages' during its initialization is never read

Signed-off-by: Colin Ian King <colin.king@canonical.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>
2017-09-25 18:22:30 -07:00
Linus Torvalds
89fd915c40 libnvdimm for 4.14
* Media error handling support in the Block Translation Table (BTT)
   driver is reworked to address sleeping-while-atomic locking and
   memory-allocation-context conflicts.
 
 * The dax_device lookup overhead for xfs and ext4 is moved out of the
   iomap hot-path to a mount-time lookup.
 
 * A new 'ecc_unit_size' sysfs attribute is added to advertise the
   read-modify-write boundary property of a persistent memory range.
 
 * Preparatory fix-ups for arm and powerpc pmem support are included
   along with other miscellaneous fixes.
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Merge tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm from Dan Williams:
 "A rework of media error handling in the BTT driver and other updates.
  It has appeared in a few -next releases and collected some late-
  breaking build-error and warning fixups as a result.

  Summary:

   - Media error handling support in the Block Translation Table (BTT)
     driver is reworked to address sleeping-while-atomic locking and
     memory-allocation-context conflicts.

   - The dax_device lookup overhead for xfs and ext4 is moved out of the
     iomap hot-path to a mount-time lookup.

   - A new 'ecc_unit_size' sysfs attribute is added to advertise the
     read-modify-write boundary property of a persistent memory range.

   - Preparatory fix-ups for arm and powerpc pmem support are included
     along with other miscellaneous fixes"

* tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (26 commits)
  libnvdimm, btt: fix format string warnings
  libnvdimm, btt: clean up warning and error messages
  ext4: fix null pointer dereference on sbi
  libnvdimm, nfit: move the check on nd_reserved2 to the endpoint
  dax: fix FS_DAX=n BLOCK=y compilation
  libnvdimm: fix integer overflow static analysis warning
  libnvdimm, nd_blk: remove mmio_flush_range()
  libnvdimm, btt: rework error clearing
  libnvdimm: fix potential deadlock while clearing errors
  libnvdimm, btt: cache sector_size in arena_info
  libnvdimm, btt: ensure that flags were also unchanged during a map_read
  libnvdimm, btt: refactor map entry operations with macros
  libnvdimm, btt: fix a missed NVDIMM_IO_ATOMIC case in the write path
  libnvdimm, nfit: export an 'ecc_unit_size' sysfs attribute
  ext4: perform dax_device lookup at mount
  ext2: perform dax_device lookup at mount
  xfs: perform dax_device lookup at mount
  dax: introduce a fs_dax_get_by_bdev() helper
  libnvdimm, btt: check memory allocation failure
  libnvdimm, label: fix index block size calculation
  ...
2017-09-11 13:10:57 -07:00
Dan Williams
486aff5e04 xfs: perform dax_device lookup at mount
The ->iomap_begin() operation is a hot path, so cache the
fs_dax_get_by_host() result at mount time to avoid the incurring the
hash lookup overhead on a per-i/o basis.

Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31 09:31:47 -07:00
Christoph Hellwig
74d46992e0 block: replace bi_bdev with a gendisk pointer and partitions index
This way we don't need a block_device structure to submit I/O.  The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open.  Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).

For the actual I/O path all that we need is the gendisk, which exists
once per block device.  But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.

Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:49:55 -06:00
Linus Torvalds
642338ba33 Changes for 4.13:
- Avoid quotacheck deadlocks
 - Fix transaction overflows when bunmapping fragmented files
 - Refactor directory readahead
 - Allow admin to configure if ASSERT is fatal
 - Improve transaction usage detail logging during overflows
 - Minor cleanups
 - Don't leak log items when the log shuts down
 - Remove double-underscore typedefs
 - Various preparation for online scrubbing
 - Introduce new error injection configuration sysfs knobs
 - Refactor dq_get_next to use extent map directly
 - Fix problems with iterating the page cache for unwritten data
 - Implement SEEK_{HOLE,DATA} via iomap
 - Refactor XFS to use iomap SEEK_HOLE and SEEK_DATA
 - Don't use MAXPATHLEN to check on-disk symlink target lengths
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Merge tag 'xfs-4.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull XFS updates from Darrick Wong:
 "Here are some changes for you for 4.13. For the most part it's fixes
  for bugs and deadlock problems, and preparation for online fsck in
  some future merge window.

   - Avoid quotacheck deadlocks

   - Fix transaction overflows when bunmapping fragmented files

   - Refactor directory readahead

   - Allow admin to configure if ASSERT is fatal

   - Improve transaction usage detail logging during overflows

   - Minor cleanups

   - Don't leak log items when the log shuts down

   - Remove double-underscore typedefs

   - Various preparation for online scrubbing

   - Introduce new error injection configuration sysfs knobs

   - Refactor dq_get_next to use extent map directly

   - Fix problems with iterating the page cache for unwritten data

   - Implement SEEK_{HOLE,DATA} via iomap

   - Refactor XFS to use iomap SEEK_HOLE and SEEK_DATA

   - Don't use MAXPATHLEN to check on-disk symlink target lengths"

* tag 'xfs-4.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (48 commits)
  xfs: don't crash on unexpected holes in dir/attr btrees
  xfs: rename MAXPATHLEN to XFS_SYMLINK_MAXLEN
  xfs: fix contiguous dquot chunk iteration livelock
  xfs: Switch to iomap for SEEK_HOLE / SEEK_DATA
  vfs: Add iomap_seek_hole and iomap_seek_data helpers
  vfs: Add page_cache_seek_hole_data helper
  xfs: remove a whitespace-only line from xfs_fs_get_nextdqblk
  xfs: rewrite xfs_dq_get_next_id using xfs_iext_lookup_extent
  xfs: Check for m_errortag initialization in xfs_errortag_test
  xfs: grab dquots without taking the ilock
  xfs: fix semicolon.cocci warnings
  xfs: Don't clear SGID when inheriting ACLs
  xfs: free cowblocks and retry on buffered write ENOSPC
  xfs: replace log_badcrc_factor knob with error injection tag
  xfs: convert drop_writes to use the errortag mechanism
  xfs: remove unneeded parameter from XFS_TEST_ERROR
  xfs: expose errortag knobs via sysfs
  xfs: make errortag a per-mountpoint structure
  xfs: free uncommitted transactions during log recovery
  xfs: don't allow bmap on rt files
  ...
2017-07-10 10:51:53 -07:00
Linus Torvalds
c6b1e36c8f Merge branch 'for-4.13/block' of git://git.kernel.dk/linux-block
Pull core block/IO updates from Jens Axboe:
 "This is the main pull request for the block layer for 4.13. Not a huge
  round in terms of features, but there's a lot of churn related to some
  core cleanups.

  Note this depends on the UUID tree pull request, that Christoph
  already sent out.

  This pull request contains:

   - A series from Christoph, unifying the error/stats codes in the
     block layer. We now use blk_status_t everywhere, instead of using
     different schemes for different places.

   - Also from Christoph, some cleanups around request allocation and IO
     scheduler interactions in blk-mq.

   - And yet another series from Christoph, cleaning up how we handle
     and do bounce buffering in the block layer.

   - A blk-mq debugfs series from Bart, further improving on the support
     we have for exporting internal information to aid debugging IO
     hangs or stalls.

   - Also from Bart, a series that cleans up the request initialization
     differences across types of devices.

   - A series from Goldwyn Rodrigues, allowing the block layer to return
     failure if we will block and the user asked for non-blocking.

   - Patch from Hannes for supporting setting loop devices block size to
     that of the underlying device.

   - Two series of patches from Javier, fixing various issues with
     lightnvm, particular around pblk.

   - A series from me, adding support for write hints. This comes with
     NVMe support as well, so applications can help guide data placement
     on flash to improve performance, latencies, and write
     amplification.

   - A series from Ming, improving and hardening blk-mq support for
     stopping/starting and quiescing hardware queues.

   - Two pull requests for NVMe updates. Nothing major on the feature
     side, but lots of cleanups and bug fixes. From the usual crew.

   - A series from Neil Brown, greatly improving the bio rescue set
     support. Most notably, this kills the bio rescue work queues, if we
     don't really need them.

   - Lots of other little bug fixes that are all over the place"

* 'for-4.13/block' of git://git.kernel.dk/linux-block: (217 commits)
  lightnvm: pblk: set line bitmap check under debug
  lightnvm: pblk: verify that cache read is still valid
  lightnvm: pblk: add initialization check
  lightnvm: pblk: remove target using async. I/Os
  lightnvm: pblk: use vmalloc for GC data buffer
  lightnvm: pblk: use right metadata buffer for recovery
  lightnvm: pblk: schedule if data is not ready
  lightnvm: pblk: remove unused return variable
  lightnvm: pblk: fix double-free on pblk init
  lightnvm: pblk: fix bad le64 assignations
  nvme: Makefile: remove dead build rule
  blk-mq: map all HWQ also in hyperthreaded system
  nvmet-rdma: register ib_client to not deadlock in device removal
  nvme_fc: fix error recovery on link down.
  nvmet_fc: fix crashes on bad opcodes
  nvme_fc: Fix crash when nvme controller connection fails.
  nvme_fc: replace ioabort msleep loop with completion
  nvme_fc: fix double calls to nvme_cleanup_cmd()
  nvme-fabrics: verify that a controller returns the correct NQN
  nvme: simplify nvme_dev_attrs_are_visible
  ...
2017-07-03 10:34:51 -07:00
Darrick J. Wong
c8ce540db5 xfs: remove double-underscore integer types
This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs.  This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-06-19 14:11:33 -07:00
Brian Foster
7912e7fef2 xfs: push buffer of flush locked dquot to avoid quotacheck deadlock
Reclaim during quotacheck can lead to deadlocks on the dquot flush
lock:

 - Quotacheck populates a local delwri queue with the physical dquot
   buffers.
 - Quotacheck performs the xfs_qm_dqusage_adjust() bulkstat and
   dirties all of the dquots.
 - Reclaim kicks in and attempts to flush a dquot whose buffer is
   already queud on the quotacheck queue. The flush succeeds but
   queueing to the reclaim delwri queue fails as the backing buffer is
   already queued. The flush unlock is now deferred to I/O completion
   of the buffer from the quotacheck queue.
 - The dqadjust bulkstat continues and dirties the recently flushed
   dquot once again.
 - Quotacheck proceeds to the xfs_qm_flush_one() walk which requires
   the flush lock to update the backing buffers with the in-core
   recalculated values. It deadlocks on the redirtied dquot as the
   flush lock was already acquired by reclaim, but the buffer resides
   on the local delwri queue which isn't submitted until the end of
   quotacheck.

This is reproduced by running quotacheck on a filesystem with a
couple million inodes in low memory (512MB-1GB) situations. This is
a regression as of commit 43ff2122e6 ("xfs: on-stack delayed write
buffer lists"), which removed a trylock and buffer I/O submission
from the quotacheck dquot flush sequence.

Quotacheck first resets and collects the physical dquot buffers in a
delwri queue. Then, it traverses the filesystem inodes via bulkstat,
updates the in-core dquots, flushes the corrected dquots to the
backing buffers and finally submits the delwri queue for I/O. Since
the backing buffers are queued across the entire quotacheck
operation, dquot reclaim cannot possibly complete a dquot flush
before quotacheck completes.

Therefore, quotacheck must submit the buffer for I/O in order to
cycle the flush lock and flush the dirty in-core dquot to the
buffer. Add a delwri queue buffer push mechanism to submit an
individual buffer for I/O without losing the delwri queue status and
use it from quotacheck to avoid the deadlock. This restores
quotacheck behavior to as before the regression was introduced.

Reported-by: Martin Svec <martin.svec@zoner.cz>
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>
2017-06-19 08:59:10 -07:00
Jens Axboe
8f66439eec Linux 4.12-rc5
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Merge tag 'v4.12-rc5' into for-4.13/block

We've already got a few conflicts and upcoming work depends on some of the
changes that have gone into mainline as regression fixes for this series.

Pull in 4.12-rc5 to resolve these conflicts and make it easier on down stream
trees to continue working on 4.13 changes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-12 08:30:13 -06:00
Christoph Hellwig
4e4cbee93d block: switch bios to blk_status_t
Replace bi_error with a new bi_status to allow for a clear conversion.
Note that device mapper overloaded bi_error with a private value, which
we'll have to keep arround at least for now and thus propagate to a
proper blk_status_t value.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09 09:27:32 -06:00
Brian Foster
95989c46d2 xfs: fix spurious spin_is_locked() assert failures on non-smp kernels
The 0-day kernel test robot reports assertion failures on
!CONFIG_SMP kernels due to failed spin_is_locked() checks. As it
turns out, spin_is_locked() is hardcoded to return zero on
!CONFIG_SMP kernels and so this function cannot be relied on to
verify spinlock state in this configuration.

To avoid this problem, replace the associated asserts with lockdep
variants that do the right thing regardless of kernel configuration.
Drop the one assert that checks for an unlocked lock as there is no
suitable lockdep variant for that case. This moves the spinlock
checks from XFS debug code to lockdep, but generally provides the
same level of protection.

Reported-by: kbuild test robot <fengguang.wu@intel.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>
2017-06-08 08:23:07 -07:00
Brian Foster
63db7c815b xfs: use ->b_state to fix buffer I/O accounting release race
We've had user reports of unmount hangs in xfs_wait_buftarg() that
analysis shows is due to btp->bt_io_count == -1. bt_io_count
represents the count of in-flight asynchronous buffers and thus
should always be >= 0. xfs_wait_buftarg() waits for this value to
stabilize to zero in order to ensure that all untracked (with
respect to the lru) buffers have completed I/O processing before
unmount proceeds to tear down in-core data structures.

The value of -1 implies an I/O accounting decrement race. Indeed,
the fact that xfs_buf_ioacct_dec() is called from xfs_buf_rele()
(where the buffer lock is no longer held) means that bp->b_flags can
be updated from an unsafe context. While a user-level reproducer is
currently not available, some intrusive hacks to run racing buffer
lookups/ioacct/releases from multiple threads was used to
successfully manufacture this problem.

Existing callers do not expect to acquire the buffer lock from
xfs_buf_rele(). Therefore, we can not safely update ->b_flags from
this context. It turns out that we already have separate buffer
state bits and associated serialization for dealing with buffer LRU
state in the form of ->b_state and ->b_lock. Therefore, replace the
_XBF_IN_FLIGHT flag with a ->b_state variant, update the I/O
accounting wrappers appropriately and make sure they are used with
the correct locking. This ensures that buffer in-flight state can be
modified at buffer release time without racing with modifications
from a buffer lock holder.

Fixes: 9c7504aa72 ("xfs: track and serialize in-flight async buffers against unmount")
Cc: <stable@vger.kernel.org> # v4.8+
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Libor Pechacek <lpechacek@suse.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-05-31 08:22:52 -07:00
Linus Torvalds
d484467c86 Changes for 4.12:
- various code cleanups
 - introduce GETFSMAP ioctl
 - various refactoring
 - avoid dio reads past eof
 - fix memory corruption and other errors with fragmented directory blocks
 - fix accidental userspace memory corruptions
 - publish fs uuid in superblock
 - make fstrim terminatable
 - fix race between quotaoff and in-core inode creation
 - Avoid use-after-free when finishing up w/ buffer heads
 - Reserve enough space to handle bmap tree resizing during cow remap
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Merge tag 'xfs-4.12-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Darrick Wong:
 "Here are the XFS changes for 4.12. The big new feature for this
  release is the new space mapping ioctl that we've been discussing
  since LSF2016, but other than that most of the patches are larger bug
  fixes, memory corruption prevention, and other cleanups.

  Summary:
   - various code cleanups
   - introduce GETFSMAP ioctl
   - various refactoring
   - avoid dio reads past eof
   - fix memory corruption and other errors with fragmented directory blocks
   - fix accidental userspace memory corruptions
   - publish fs uuid in superblock
   - make fstrim terminatable
   - fix race between quotaoff and in-core inode creation
   - avoid use-after-free when finishing up w/ buffer heads
   - reserve enough space to handle bmap tree resizing during cow remap"

* tag 'xfs-4.12-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (53 commits)
  xfs: fix use-after-free in xfs_finish_page_writeback
  xfs: reserve enough blocks to handle btree splits when remapping
  xfs: wait on new inodes during quotaoff dquot release
  xfs: update ag iterator to support wait on new inodes
  xfs: support ability to wait on new inodes
  xfs: publish UUID in struct super_block
  xfs: Allow user to kill fstrim process
  xfs: better log intent item refcount checking
  xfs: fix up quotacheck buffer list error handling
  xfs: remove xfs_trans_ail_delete_bulk
  xfs: don't use bool values in trace buffers
  xfs: fix getfsmap userspace memory corruption while setting OF_LAST
  xfs: fix __user annotations for xfs_ioc_getfsmap
  xfs: corruption needs to respect endianess too!
  xfs: use NULL instead of 0 to initialize a pointer in xfs_ioc_getfsmap
  xfs: use NULL instead of 0 to initialize a pointer in xfs_getfsmap
  xfs: simplify validation of the unwritten extent bit
  xfs: remove unused values from xfs_exntst_t
  xfs: remove the unused XFS_MAXLINK_1 define
  xfs: more do_div cleanups
  ...
2017-05-06 11:46:16 -07:00
Michal Hocko
9ba1fb2c60 xfs: use memalloc_nofs_{save,restore} instead of memalloc_noio*
kmem_zalloc_large and _xfs_buf_map_pages use memalloc_noio_{save,restore}
API to prevent from reclaim recursion into the fs because vmalloc can
invoke unconditional GFP_KERNEL allocations and these functions might be
called from the NOFS contexts.  The memalloc_noio_save will enforce
GFP_NOIO context which is even weaker than GFP_NOFS and that seems to be
unnecessary.  Let's use memalloc_nofs_{save,restore} instead as it
should provide exactly what we need here - implicit GFP_NOFS context.

Link: http://lkml.kernel.org/r/20170306131408.9828-6-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-03 15:52:09 -07:00
Brian Foster
20e8a06378 xfs: fix up quotacheck buffer list error handling
The quotacheck error handling of the delwri buffer list assumes the
resident buffers are locked and doesn't clear the _XBF_DELWRI_Q flag
on the buffers that are dequeued. This can lead to assert failures
on buffer release and possibly other locking problems.

Move this code to a delwri queue cancel helper function to
encapsulate the logic required to properly release buffers from a
delwri queue. Update the helper to clear the delwri queue flag and
call it from quotacheck.

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>
2017-04-25 09:40:42 -07:00
Ingo Molnar
5b3cc15aff sched/headers: Prepare to move the memalloc_noio_*() APIs to <linux/sched/mm.h>
Update the .c files that depend on these APIs.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:33 +01:00
Jens Axboe
818551e2b2 Merge branch 'for-4.11/next' into for-4.11/linus-merge
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-17 14:08:19 -07:00
Jan Kara
efa7c9f97e block: Get rid of blk_get_backing_dev_info()
blk_get_backing_dev_info() is now a simple dereference. Remove that
function and simplify some code around that.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-02 08:21:32 -07:00