xfs: separate dquot buffer reads from xfs_dqflush

commit a40fe30868ba433ac08376e30132400bec067583 upstream

The first step towards holding the dquot buffer in the li_buf instead of
reading it in the AIL is to separate the part that reads the buffer from
the actual flush code.  There should be no functional changes.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 30 insertions, 7 deletions

diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index 7e2307921deb..4f50d8ce125f 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -146,17 +146,28 @@ xfs_qm_dqpurge(
 		 * We don't care about getting disk errors here. We need
 		 * to purge this dquot anyway, so we go ahead regardless.
 		 */
-		error = xfs_qm_dqflush(dqp, &bp);
+		error = xfs_dquot_read_buf(NULL, dqp, &bp);
+		if (error == -EAGAIN) {
+			xfs_dqfunlock(dqp);
+			dqp->q_flags &= ~XFS_DQFLAG_FREEING;
+			goto out_unlock;
+		}
+		if (error)
+			goto out_funlock;
+
+		/*
+		 * dqflush completes dqflock on error, and the bwrite ioend
+		 * does it on success.
+		 */
+		error = xfs_qm_dqflush(dqp, bp);
 		if (!error) {
 			error = xfs_bwrite(bp);
 			xfs_buf_relse(bp);
-		} else if (error == -EAGAIN) {
-			dqp->q_flags &= ~XFS_DQFLAG_FREEING;
-			goto out_unlock;
 		}
 		xfs_dqflock(dqp);
 	}
 
+out_funlock:
 	ASSERT(atomic_read(&dqp->q_pincount) == 0);
 	ASSERT(xlog_is_shutdown(dqp->q_logitem.qli_item.li_log) ||
 		!test_bit(XFS_LI_IN_AIL, &dqp->q_logitem.qli_item.li_flags));
@@ -462,7 +473,17 @@ xfs_qm_dquot_isolate(
 		/* we have to drop the LRU lock to flush the dquot */
 		spin_unlock(lru_lock);
 
-		error = xfs_qm_dqflush(dqp, &bp);
+		error = xfs_dquot_read_buf(NULL, dqp, &bp);
+		if (error) {
+			xfs_dqfunlock(dqp);
+			goto out_unlock_dirty;
+		}
+
+		/*
+		 * dqflush completes dqflock on error, and the delwri ioend
+		 * does it on success.
+		 */
+		error = xfs_qm_dqflush(dqp, bp);
 		if (error)
 			goto out_unlock_dirty;
 
@@ -1287,11 +1308,13 @@ xfs_qm_flush_one(
 		goto out_unlock;
 	}
 
-	error = xfs_qm_dqflush(dqp, &bp);
+	error = xfs_dquot_read_buf(NULL, dqp, &bp);
 	if (error)
 		goto out_unlock;
 
-	xfs_buf_delwri_queue(bp, buffer_list);
+	error = xfs_qm_dqflush(dqp, bp);
+	if (!error)
+		xfs_buf_delwri_queue(bp, buffer_list);
 	xfs_buf_relse(bp);
 out_unlock:
 	xfs_dqunlock(dqp);