[PATCH] ceph: flush release queue when handling caps for unknown inode

[PATCH] ceph: flush release queue when handling caps for unknown inode

[Jeff Layton]

It's possible for the VFS to completely forget about an inode, but for
it to still be sitting on the cap release queue. If the MDS sends the
client a cap message for such an inode, it just ignores it today, which
can lead to a stall of up to 5s until the cap release queue is flushed.

If we get a cap message for an inode that can't be located, then go
ahead and flush the cap release queue.

Cc: stable@vger.kernel.org
Fixes: 1e9c2eb6811e ("ceph: delete stale dentry when last reference is dropped")
Reported-by: Andrej Filipčič <andrej.filipcic@ijs.si>
Fix-suggested-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/ceph/caps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 27c2e60f33dc..41eb999dadf0 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -4070,7 +4070,7 @@ void ceph_handle_caps(struct ceph_mds_session *session,
 			__ceph_queue_cap_release(session, cap);
 			spin_unlock(&session->s_cap_lock);
 		}
-		goto done;
+		goto flush_cap_releases;
 	}
 
 	/* these will work even if we don't have a cap yet */
-- 
2.26.2