From: Jeff Layton <jlayton@kernel.org>
Date: Thu, 10 Dec 2020 13:35:46 -0500
Subject: ceph: fix flush_snap logic after putting caps
Git-commit: 64f36da5625f7f9853b86750eaa89d499d16a2e9
Patch-mainline: v5.12-rc1
References: bsc#1182853

A primary reason for skipping ceph_check_caps after putting the
references was to avoid the locking in ceph_check_caps during a
reconnect. __ceph_put_cap_refs can still call ceph_flush_snaps in that
case though, and that takes many of the same inconvenient locks.

Fix the logic in __ceph_put_cap_refs to skip flushing snaps when the
skip_checking_caps flag is set.

Fixes: e64f44a88465 ("ceph: skip checking caps when session reconnecting and releasing reqs")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
 fs/ceph/caps.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 255a512f1277..638d18c198ea 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -3093,10 +3093,12 @@ static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had,
 	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
 	     last ? " last" : "", put ? " put" : "");
 
-	if (last && !skip_checking_caps)
-		ceph_check_caps(ci, 0, NULL);
-	else if (flushsnaps)
-		ceph_flush_snaps(ci, NULL);
+	if (!skip_checking_caps) {
+		if (last)
+			ceph_check_caps(ci, 0, NULL);
+		else if (flushsnaps)
+			ceph_flush_snaps(ci, NULL);
+	}
 	if (wake)
 		wake_up_all(&ci->i_cap_wq);
 	while (put-- > 0)