NFSv4: Handle NFS4ERR_GRACE when recovering an expired lease.

If our lease expires, and the server reboots while we're recovering, we
need to be able to wait until the grace period is over.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/nfs4proc.c

@@ -1488,18 +1488,24 @@ static int _nfs4_open_expired(struct nfs_open_context *ctx, struct nfs4_state *s
 	return ret;
 }
 
-static inline int nfs4_do_open_expired(struct nfs_open_context *ctx, struct nfs4_state *state)
+static int nfs4_do_open_expired(struct nfs_open_context *ctx, struct nfs4_state *state)
 {
 	struct nfs_server *server = NFS_SERVER(state->inode);
 	struct nfs4_exception exception = { };
 	int err;
 
 	do {
 		err = _nfs4_open_expired(ctx, state);
-		if (err != -NFS4ERR_DELAY)
-			break;
-		nfs4_handle_exception(server, err, &exception);
+		switch (err) {
+		default:
+			goto out;
+		case -NFS4ERR_GRACE:
+		case -NFS4ERR_DELAY:
+			nfs4_handle_exception(server, err, &exception);
+			err = 0;
+		}
 	} while (exception.retry);
+out:
 	return err;
 }
 
@@ -4049,10 +4055,16 @@ static int nfs4_lock_expired(struct nfs4_state *state, struct file_lock *request
 		if (test_bit(NFS_DELEGATED_STATE, &state->flags) != 0)
 			return 0;
 		err = _nfs4_do_setlk(state, F_SETLK, request, 0);
-		if (err != -NFS4ERR_DELAY)
-			break;
-		nfs4_handle_exception(server, err, &exception);
+		switch (err) {
+		default:
+			goto out;
+		case -NFS4ERR_GRACE:
+		case -NFS4ERR_DELAY:
+			nfs4_handle_exception(server, err, &exception);
+			err = 0;
+		}
 	} while (exception.retry);
+out:
 	return err;
 }