This is a note to let you know that I've just added the patch titled
xfs: Properly retry failed dquot items in case of error during buffer writeback
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xfs-properly-retry-failed-dquot-items-in-case-of-error-during-buffer-writeback.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Thu Feb 1 13:45:42 CET 2018
From: Carlos Maiolino <cmaiolino@xxxxxxxxxx>
Date: Tue, 28 Nov 2017 08:54:10 -0800
Subject: xfs: Properly retry failed dquot items in case of error during buffer writeback
From: Carlos Maiolino <cmaiolino@xxxxxxxxxx>
[ Upstream commit 373b0589dc8d58bc09c9a28d03611ae4fb216057 ]
Once the inode item writeback errors is already fixed, it's time to fix the same
problem in dquot code.
Although there were no reports of users hitting this bug in dquot code (at least
none I've seen), the bug is there and I was already planning to fix it when the
correct approach to fix the inodes part was decided.
This patch aims to fix the same problem in dquot code, regarding failed buffers
being unable to be resubmitted once they are flush locked.
Tested with the recently test-case sent to fstests list by Hou Tao.
Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx>
Signed-off-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx>
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/xfs/xfs_dquot.c | 14 +++++++++++---
fs/xfs/xfs_dquot_item.c | 40 ++++++++++++++++++++++++++++++++++++++--
2 files changed, 49 insertions(+), 5 deletions(-)
--- a/fs/xfs/xfs_dquot.c
+++ b/fs/xfs/xfs_dquot.c
@@ -987,14 +987,22 @@ xfs_qm_dqflush_done(
* holding the lock before removing the dquot from the AIL.
*/
if ((lip->li_flags & XFS_LI_IN_AIL) &&
- lip->li_lsn == qip->qli_flush_lsn) {
+ ((lip->li_lsn == qip->qli_flush_lsn) ||
+ (lip->li_flags & XFS_LI_FAILED))) {
/* xfs_trans_ail_delete() drops the AIL lock. */
spin_lock(&ailp->xa_lock);
- if (lip->li_lsn == qip->qli_flush_lsn)
+ if (lip->li_lsn == qip->qli_flush_lsn) {
xfs_trans_ail_delete(ailp, lip, SHUTDOWN_CORRUPT_INCORE);
- else
+ } else {
+ /*
+ * Clear the failed state since we are about to drop the
+ * flush lock
+ */
+ if (lip->li_flags & XFS_LI_FAILED)
+ xfs_clear_li_failed(lip);
spin_unlock(&ailp->xa_lock);
+ }
}
/*
--- a/fs/xfs/xfs_dquot_item.c
+++ b/fs/xfs/xfs_dquot_item.c
@@ -137,6 +137,26 @@ xfs_qm_dqunpin_wait(
wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
}
+/*
+ * Callback used to mark a buffer with XFS_LI_FAILED when items in the buffer
+ * have been failed during writeback
+ *
+ * this informs the AIL that the dquot is already flush locked on the next push,
+ * and acquires a hold on the buffer to ensure that it isn't reclaimed before
+ * dirty data makes it to disk.
+ */
+STATIC void
+xfs_dquot_item_error(
+ struct xfs_log_item *lip,
+ struct xfs_buf *bp)
+{
+ struct xfs_dquot *dqp;
+
+ dqp = DQUOT_ITEM(lip)->qli_dquot;
+ ASSERT(!completion_done(&dqp->q_flush));
+ xfs_set_li_failed(lip, bp);
+}
+
STATIC uint
xfs_qm_dquot_logitem_push(
struct xfs_log_item *lip,
@@ -144,13 +164,28 @@ xfs_qm_dquot_logitem_push(
__acquires(&lip->li_ailp->xa_lock)
{
struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
- struct xfs_buf *bp = NULL;
+ struct xfs_buf *bp = lip->li_buf;
uint rval = XFS_ITEM_SUCCESS;
int error;
if (atomic_read(&dqp->q_pincount) > 0)
return XFS_ITEM_PINNED;
+ /*
+ * The buffer containing this item failed to be written back
+ * previously. Resubmit the buffer for IO
+ */
+ if (lip->li_flags & XFS_LI_FAILED) {
+ if (!xfs_buf_trylock(bp))
+ return XFS_ITEM_LOCKED;
+
+ if (!xfs_buf_resubmit_failed_buffers(bp, lip, buffer_list))
+ rval = XFS_ITEM_FLUSHING;
+
+ xfs_buf_unlock(bp);
+ return rval;
+ }
+
if (!xfs_dqlock_nowait(dqp))
return XFS_ITEM_LOCKED;
@@ -242,7 +277,8 @@ static const struct xfs_item_ops xfs_dqu
.iop_unlock = xfs_qm_dquot_logitem_unlock,
.iop_committed = xfs_qm_dquot_logitem_committed,
.iop_push = xfs_qm_dquot_logitem_push,
- .iop_committing = xfs_qm_dquot_logitem_committing
+ .iop_committing = xfs_qm_dquot_logitem_committing,
+ .iop_error = xfs_dquot_item_error
};
/*
Patches currently in stable-queue which might be from cmaiolino@xxxxxxxxxx are
queue-4.14/xfs-properly-retry-failed-dquot-items-in-case-of-error-during-buffer-writeback.patch