diff options
author | Dave Chinner <dchinner@redhat.com> | 2012-04-23 07:58:46 +0200 |
---|---|---|
committer | Ben Myers <bpm@sgi.com> | 2012-05-14 23:20:42 +0200 |
commit | 0e95f19ad983e72a9cb93a67b3290b58f0467b36 (patch) | |
tree | 2b3117e20f1e739d5cb560b1b1b32f3fdc8e3ee5 /fs | |
parent | xfs: fix buffer lookup race on allocation failure (diff) | |
download | linux-0e95f19ad983e72a9cb93a67b3290b58f0467b36.tar.xz linux-0e95f19ad983e72a9cb93a67b3290b58f0467b36.zip |
xfs: check for buffer errors before waiting
If we call xfs_buf_iowait() on a buffer that failed dispatch due to
an IO error, it will wait forever for an Io that does not exist.
This is hndled in xfs_buf_read, but there is other code that calls
xfs_buf_iowait directly that doesn't.
Rather than make the call sites have to handle checking for dispatch
errors and then checking for completion errors, make
xfs_buf_iowait() check for dispatch errors on the buffer before
waiting. This means we handle both dispatch and completion errors
with one set of error handling at the caller sites.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/xfs/xfs_buf.c | 22 | ||||
-rw-r--r-- | fs/xfs/xfs_buf.h | 2 | ||||
-rw-r--r-- | fs/xfs/xfs_log_recover.c | 2 |
3 files changed, 13 insertions, 13 deletions
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index da2541e5ff81..86d9af70ab3b 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -600,17 +600,15 @@ _xfs_buf_read( xfs_buf_t *bp, xfs_buf_flags_t flags) { - int status; - ASSERT(!(flags & XBF_WRITE)); ASSERT(bp->b_bn != XFS_BUF_DADDR_NULL); bp->b_flags &= ~(XBF_WRITE | XBF_ASYNC | XBF_READ_AHEAD); bp->b_flags |= flags & (XBF_READ | XBF_ASYNC | XBF_READ_AHEAD); - status = xfs_buf_iorequest(bp); - if (status || bp->b_error || (flags & XBF_ASYNC)) - return status; + xfs_buf_iorequest(bp); + if (flags & XBF_ASYNC) + return 0; return xfs_buf_iowait(bp); } @@ -695,7 +693,7 @@ xfs_buf_read_uncached( xfsbdstrat(mp, bp); error = xfs_buf_iowait(bp); - if (error || bp->b_error) { + if (error) { xfs_buf_relse(bp); return NULL; } @@ -1252,7 +1250,7 @@ next_chunk: } } -int +void xfs_buf_iorequest( xfs_buf_t *bp) { @@ -1273,13 +1271,12 @@ xfs_buf_iorequest( _xfs_buf_ioend(bp, 0); xfs_buf_rele(bp); - return 0; } /* - * Waits for I/O to complete on the buffer supplied. - * It returns immediately if no I/O is pending. - * It returns the I/O error code, if any, or 0 if there was no error. + * Waits for I/O to complete on the buffer supplied. It returns immediately if + * no I/O is pending or there is already a pending error on the buffer. It + * returns the I/O error code, if any, or 0 if there was no error. */ int xfs_buf_iowait( @@ -1287,7 +1284,8 @@ xfs_buf_iowait( { trace_xfs_buf_iowait(bp, _RET_IP_); - wait_for_completion(&bp->b_iowait); + if (!bp->b_error) + wait_for_completion(&bp->b_iowait); trace_xfs_buf_iowait_done(bp, _RET_IP_); return bp->b_error; diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h index 7083cf44d95f..87a474853f8a 100644 --- a/fs/xfs/xfs_buf.h +++ b/fs/xfs/xfs_buf.h @@ -191,7 +191,7 @@ extern int xfs_bdstrat_cb(struct xfs_buf *); extern void xfs_buf_ioend(xfs_buf_t *, int); extern void xfs_buf_ioerror(xfs_buf_t *, int); extern void xfs_buf_ioerror_alert(struct xfs_buf *, const char *func); -extern int xfs_buf_iorequest(xfs_buf_t *); +extern void xfs_buf_iorequest(xfs_buf_t *); extern int xfs_buf_iowait(xfs_buf_t *); extern void xfs_buf_iomove(xfs_buf_t *, size_t, size_t, void *, xfs_buf_rw_t); diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index 5540e79da6f5..e1577e763fdf 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -179,6 +179,7 @@ xlog_bread_noalign( XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no); XFS_BUF_READ(bp); XFS_BUF_SET_COUNT(bp, BBTOB(nbblks)); + bp->b_error = 0; xfsbdstrat(log->l_mp, bp); error = xfs_buf_iowait(bp); @@ -266,6 +267,7 @@ xlog_bwrite( xfs_buf_hold(bp); xfs_buf_lock(bp); XFS_BUF_SET_COUNT(bp, BBTOB(nbblks)); + bp->b_error = 0; error = xfs_bwrite(bp); if (error) |