xfs: untangle SYNC_WAIT and SYNC_TRYLOCK meanings for xfs_qm_dqflush

Only skip pinned dquots if SYNC_TRYLOCK is specified, and adjust the callers
to keep the behaviour unchanged.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

fs/xfs/xfs_dquot.c

@@ -1169,7 +1169,7 @@ xfs_qm_dqflush(
 	 * If not dirty, or it's pinned and we are not supposed to block, nada.
 	 */
 	if (!XFS_DQ_IS_DIRTY(dqp) ||
-	    (!(flags & SYNC_WAIT) && atomic_read(&dqp->q_pincount) > 0)) {
+	    ((flags & SYNC_TRYLOCK) && atomic_read(&dqp->q_pincount) > 0)) {
 		xfs_dqfunlock(dqp);
 		return 0;
 	}

fs/xfs/xfs_dquot_item.c

@@ -133,7 +133,7 @@ xfs_qm_dquot_logitem_push(
 	 * lock without sleeping, then there must not have been
 	 * anyone in the process of flushing the dquot.
 	 */
-	error = xfs_qm_dqflush(dqp, 0);
+	error = xfs_qm_dqflush(dqp, SYNC_TRYLOCK);
 	if (error)
 		xfs_warn(dqp->q_mount, "%s: push error %d on dqp %p",
 			__func__, error, dqp);

fs/xfs/xfs_qm.c

@@ -1661,7 +1661,7 @@ xfs_qm_quotacheck(
 	 * successfully.
 	 */
 	if (!error)
-		error = xfs_qm_dqflush_all(mp, 0);
+		error = xfs_qm_dqflush_all(mp, SYNC_TRYLOCK);
 
 	/*
 	 * We can get this error if we couldn't do a dquot allocation inside
@@ -1874,7 +1874,7 @@ xfs_qm_dqreclaim_one(void)
 			 * We flush it delayed write, so don't bother
 			 * releasing the freelist lock.
 			 */
-			error = xfs_qm_dqflush(dqp, 0);
+			error = xfs_qm_dqflush(dqp, SYNC_TRYLOCK);
 			if (error) {
 				xfs_warn(mp, "%s: dquot %p flush failed",
 					__func__, dqp);