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  1. 12 6月, 2019 2 次提交
  3. 02 5月, 2019 1 次提交
  5. 15 4月, 2019 1 次提交
    • B
      xfs: shutdown after buf release in iflush cluster abort path · 22fedd80
      由 Brian Foster 提交于 
      If xfs_iflush_cluster() fails due to corruption, the error path
issues a shutdown and simulates an I/O completion to release the
buffer. This code has a couple small problems. First, the shutdown
sequence can issue a synchronous log force, which is unsafe to do
with buffer locks held. Second, the simulated I/O completion does not
guarantee the buffer is async and thus is unlocked and released.

For example, if the last operation on the buffer was a read off disk
prior to the corruption event, XBF_ASYNC is not set and the buffer
is left locked and held upon return. This results in a memory leak
as shown by the following message on module unload:

 BUG xfs_buf (...): Objects remaining in xfs_buf on __kmem_cache_shutdown()

Fix both of these problems by setting XBF_ASYNC on the buffer prior
to the simulated I/O error and performing the shutdown immediately
after ioend processing when the buffer has been released.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      22fedd80
  7. 15 2月, 2019 2 次提交
  9. 12 2月, 2019 8 次提交
  11. 13 12月, 2018 3 次提交
  13. 29 9月, 2018 1 次提交
    • B
      xfs: remove last of unnecessary xfs_defer_cancel() callers · d5a2e289
      由 Brian Foster 提交于 
      Now that deferred operations are completely managed via
transactions, it's no longer necessary to cancel the dfops in error
paths that already cancel the associated transaction. There are a
few such calls lingering throughout the codebase.

Remove all remaining unnecessary calls to xfs_defer_cancel(). This
leaves xfs_defer_cancel() calls in two places. The first is the call
in the transaction cancel path itself, which facilitates this patch.
The second is made via the xfs_defer_finish() error path to provide
consistent error semantics with transaction commit. For example,
xfs_trans_commit() expects an xfs_defer_finish() failure to clean up
the dfops structure before it returns.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>
      d5a2e289
  15. 03 8月, 2018 3 次提交
    • B
      xfs: cancel dfops on xfs_defer_finish() error · 9b1f4e98
      由 Brian Foster 提交于 
      The current semantics of xfs_defer_finish() require the caller to
call xfs_defer_cancel() on error. This is slightly inconsistent with
transaction commit error handling where a failed commit cleans up
the transaction before returning.

More significantly, the only requirement for exposure of
->dop_pending outside of xfs_defer_finish() is so that
xfs_defer_cancel() can drain it on error. Since the only recourse of
xfs_defer_finish() errors is cancellation, mirror the transaction
logic and cancel remaining dfops before returning from
xfs_defer_finish() with an error.

Beside simplifying xfs_defer_finish() semantics, this ensures that
xfs_defer_finish() always returns with an empty ->dop_pending and
thus facilitates removal of the list from xfs_defer_ops.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      9b1f4e98
    • B
      xfs: automatic dfops inode relogging · a8198666
      由 Brian Foster 提交于 
      Inodes that are held across deferred operations are explicitly
joined to the dfops structure to ensure appropriate relogging.
While inodes are currently joined explicitly, we can detect the
conditions that require relogging at dfops finish time by inspecting
the transaction item list for inodes with ili_lock_flags == 0.

Replace the xfs_defer_ijoin() infrastructure with such detection and
automatic relogging of held inodes. This eliminates the need for the
per-dfops inode list, replaced by an on-stack variant in
xfs_defer_trans_roll().
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      a8198666
    • B
      xfs: add missing defer ijoins for held inodes · 488c919a
      由 Brian Foster 提交于 
      Log items that require relogging during deferred operations
processing are explicitly joined to the associated dfops via the
xfs_defer_*join() helpers. These calls imply that the associated
object is "held" by the transaction such that when rolled, the item
can be immediately joined to a follow up transaction. For buffers,
this means the buffer remains locked and held after each roll. For
inodes, this means that the inode remains locked.

Failure to join a held item to the dfops structure means the
associated object pins the tail of the log while dfops processing
completes, because the item never relogs and is not unlocked or
released until deferred processing completes.

Currently, all buffers that are held in transactions (XFS_BLI_HOLD)
with deferred operations are explicitly joined to the dfops. This is
not the case for inodes, however, as various contexts defer
operations to transactions with held inodes without explicit joins
to the associated dfops (and thus not relogging).

While this is not a catastrophic problem, it is not ideal. Given
that we want to eventually relog such items automatically during
dfops processing, start by explicitly adding these missing
xfs_defer_ijoin() calls. A call is added everywhere an inode is
joined to a transaction without transferring lock ownership and
said transaction runs deferred operations.

All xfs_defer_ijoin() calls will eventually be replaced by automatic
dfops inode relogging. This patch essentially implements the
behavior change that would otherwise occur due to automatic inode
dfops relogging.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      488c919a
  17. 30 7月, 2018 2 次提交
  19. 27 7月, 2018 4 次提交
  21. 12 7月, 2018 12 次提交
  23. 22 6月, 2018 1 次提交
    • D
      xfs: xfs_iflush_abort() can be called twice on cluster writeback failure · e53946db
      由 Dave Chinner 提交于 
      When a corrupt inode is detected during xfs_iflush_cluster, we can
get a shutdown ASSERT failure like this:

XFS (pmem1): Metadata corruption detected at xfs_symlink_shortform_verify+0x5c/0xa0, inode 0x86627 data fork
XFS (pmem1): Unmount and run xfs_repair
XFS (pmem1): xfs_do_force_shutdown(0x8) called from line 3372 of file fs/xfs/xfs_inode.c.  Return address = ffffffff814f4116
XFS (pmem1): Corruption of in-memory data detected.  Shutting down filesystem
XFS (pmem1): xfs_do_force_shutdown(0x1) called from line 222 of file fs/xfs/libxfs/xfs_defer.c.  Return address = ffffffff814a8a88
XFS (pmem1): xfs_do_force_shutdown(0x1) called from line 222 of file fs/xfs/libxfs/xfs_defer.c.  Return address = ffffffff814a8ef9
XFS (pmem1): Please umount the filesystem and rectify the problem(s)
XFS: Assertion failed: xfs_isiflocked(ip), file: fs/xfs/xfs_inode.h, line: 258
.....
Call Trace:
 xfs_iflush_abort+0x10a/0x110
 xfs_iflush+0xf3/0x390
 xfs_inode_item_push+0x126/0x1e0
 xfsaild+0x2c5/0x890
 kthread+0x11c/0x140
 ret_from_fork+0x24/0x30

Essentially, xfs_iflush_abort() has been called twice on the
original inode that that was flushed. This happens because the
inode has been flushed to teh buffer successfully via
xfs_iflush_int(), and so when another inode is detected as corrupt
in xfs_iflush_cluster, the buffer is marked stale and EIO, and
iodone callbacks are run on it.

Running the iodone callbacks walks across the original inode and
calls xfs_iflush_abort() on it. When xfs_iflush_cluster() returns
to xfs_iflush(), it runs the error path for that function, and that
calls xfs_iflush_abort() on the inode a second time, leading to the
above assert failure as the inode is not flush locked anymore.

This bug has been there a long time.

The simple fix would be to just avoid calling xfs_iflush_abort() in
xfs_iflush() if we've got a failure from xfs_iflush_cluster().
However, xfs_iflush_cluster() has magic delwri buffer handling that
means it may or may not have run IO completion on the buffer, and
hence sometimes we have to call xfs_iflush_abort() from
xfs_iflush(), and sometimes we shouldn't.

After reading through all the error paths and the delwri buffer
code, it's clear that the error handling in xfs_iflush_cluster() is
unnecessary. If the buffer is delwri, it leaves it on the delwri
list so that when the delwri list is submitted it sees a shutdown
fliesystem in xfs_buf_submit() and that marks the buffer stale, EIO
and runs IO completion. i.e. exactly what xfs+iflush_cluster() does
when it's not a delwri buffer. Further, marking a buffer stale
clears the _XBF_DELWRI_Q flag on the buffer, which means when
submission of the buffer occurs, it just skips over it and releases
it.

IOWs, the error handling in xfs_iflush_cluster doesn't need to care
if the buffer is already on a the delwri queue or not - it just
needs to mark the buffer stale, EIO and run completions. That means
we can just use the easy fix for xfs_iflush() to avoid the double
abort.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      e53946db