nfs4: wake any lock waiters on successful RECLAIM_COMPLETE

If we have a RECLAIM_COMPLETE with a populated cl_lock_waitq, then
that implies that a reconnect has occurred. Since we can't expect a
CB_NOTIFY_LOCK callback at that point, just wake up the entire queue
so that all the tasks can re-poll for their locks.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/nfs4proc.c

@@ -6621,8 +6621,11 @@ static int
 nfs4_wake_lock_waiter(wait_queue_entry_t *wait, unsigned int mode, int flags, void *key)
 {
 	int ret;
-	struct cb_notify_lock_args *cbnl = key;
 	struct nfs4_lock_waiter	*waiter	= wait->private;
+
+	/* NULL key means to wake up everyone */
+	if (key) {
+		struct cb_notify_lock_args	*cbnl = key;
 		struct nfs_lowner		*lowner = &cbnl->cbnl_owner,
 						*wowner = waiter->owner;
 
@@ -6635,6 +6638,7 @@ nfs4_wake_lock_waiter(wait_queue_entry_t *wait, unsigned int mode, int flags, vo
 			return 0;
 
 		waiter->notified = true;
+	}
 
 	/* override "private" so we can use default_wake_function */
 	wait->private = waiter->task;
@@ -8413,6 +8417,8 @@ static int nfs41_reclaim_complete_handle_errors(struct rpc_task *task, struct nf
 {
 	switch(task->tk_status) {
 	case 0:
+		wake_up_all(&clp->cl_lock_waitq);
+		/* Fallthrough */
 	case -NFS4ERR_COMPLETE_ALREADY:
 	case -NFS4ERR_WRONG_CRED: /* What to do here? */
 		break;