NLM: Ensure that we resend all pending blocking locks after a reclaim

commit 666b3d803a511fbc9bc5e5ea8ce66010cf03ea13 upstream.

Currently, nlmclnt_lock will break out of the for(;;) loop when
the reclaimer wakes up the blocking lock thread by setting
nlm_lck_denied_grace_period. This causes the lock request to fail
with an ENOLCK error.
The intention was always to ensure that we resend the lock request
after the grace period has expired.

Reported-by: Wangyuan Zhang <Wangyuan.Zhang@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index 8392cb8..a3a0987 100644 (file)
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -551,6 +551,9 @@ again:
                status = nlmclnt_block(block, req, NLMCLNT_POLL_TIMEOUT);
                if (status < 0)
                        break;
+               /* Resend the blocking lock request after a server reboot */
+               if (resp->status ==  nlm_lck_denied_grace_period)
+                       continue;
                if (resp->status != nlm_lck_blocked)
                        break;
        }