diff options
author | Dave Chinner <dchinner@redhat.com> | 2014-10-02 09:04:31 +1000 |
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committer | Dave Chinner <david@fromorbit.com> | 2014-10-02 09:04:31 +1000 |
commit | 61be9c529a4a715ab8679e9ca82bc3790c7ab66c (patch) | |
tree | 3e8d1c757133eb7c844cd4ba8815f4a6bc0218cb /fs/xfs/xfs_buf.h | |
parent | e8aaba9a783c8e5d2c58ebe69650ea31b91bb745 (diff) | |
download | linux-61be9c529a4a715ab8679e9ca82bc3790c7ab66c.tar.bz2 |
xfs: rework xfs_buf_bio_endio error handling
Currently the report of a bio error from completion
immediately marks the buffer with an error. The issue is that this
is racy w.r.t. synchronous IO - the submitter can see b_error being
set before the IO is complete, and hence we cannot differentiate
between submission failures and completion failures.
Add an internal b_io_error field protected by the b_lock to catch IO
completion errors, and only propagate that to the buffer during
final IO completion handling. Hence we can tell in xfs_buf_iorequest
if we've had a submission failure bey checking bp->b_error before
dropping our b_io_remaining reference - that reference will prevent
b_io_error values from being propagated to b_error in the event that
completion races with submission.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Diffstat (limited to 'fs/xfs/xfs_buf.h')
-rw-r--r-- | fs/xfs/xfs_buf.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h index 4585c1595a98..44db8cd67bda 100644 --- a/fs/xfs/xfs_buf.h +++ b/fs/xfs/xfs_buf.h @@ -158,6 +158,7 @@ typedef struct xfs_buf { struct list_head b_lru; /* lru list */ spinlock_t b_lock; /* internal state lock */ unsigned int b_state; /* internal state flags */ + int b_io_error; /* internal IO error state */ wait_queue_head_t b_waiters; /* unpin waiters */ struct list_head b_list; struct xfs_perag *b_pag; /* contains rbtree root */ |