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>
This commit is contained in:
Brian Foster 2017-04-21 12:40:44 -07:00 committed by Darrick J. Wong
parent 27af1bbf52
commit 20e8a06378
3 changed files with 26 additions and 6 deletions

View File

@ -1079,6 +1079,8 @@ void
xfs_buf_unlock(
struct xfs_buf *bp)
{
ASSERT(xfs_buf_islocked(bp));
XB_CLEAR_OWNER(bp);
up(&bp->b_sema);
@ -1814,6 +1816,28 @@ error:
return NULL;
}
/*
* Cancel a delayed write list.
*
* Remove each buffer from the list, clear the delwri queue flag and drop the
* associated buffer reference.
*/
void
xfs_buf_delwri_cancel(
struct list_head *list)
{
struct xfs_buf *bp;
while (!list_empty(list)) {
bp = list_first_entry(list, struct xfs_buf, b_list);
xfs_buf_lock(bp);
bp->b_flags &= ~_XBF_DELWRI_Q;
list_del_init(&bp->b_list);
xfs_buf_relse(bp);
}
}
/*
* Add a buffer to the delayed write list.
*

View File

@ -329,6 +329,7 @@ extern void *xfs_buf_offset(struct xfs_buf *, size_t);
extern void xfs_buf_stale(struct xfs_buf *bp);
/* Delayed Write Buffer Routines */
extern void xfs_buf_delwri_cancel(struct list_head *);
extern bool xfs_buf_delwri_queue(struct xfs_buf *, struct list_head *);
extern int xfs_buf_delwri_submit(struct list_head *);
extern int xfs_buf_delwri_submit_nowait(struct list_head *);

View File

@ -1384,12 +1384,7 @@ xfs_qm_quotacheck(
mp->m_qflags |= flags;
error_return:
while (!list_empty(&buffer_list)) {
struct xfs_buf *bp =
list_first_entry(&buffer_list, struct xfs_buf, b_list);
list_del_init(&bp->b_list);
xfs_buf_relse(bp);
}
xfs_buf_delwri_cancel(&buffer_list);
if (error) {
xfs_warn(mp,