cifs: smbd: Return -EAGAIN when transport is reconnecting

During reconnecting, the transport may have already been destroyed and is in
the process being reconnected. In this case, return -EAGAIN to not fail and
to retry this I/O.
Signed-off-by: Long Li <longli@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/transport.c

@@ -325,8 +325,11 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
 	int val = 1;
 	__be32 rfc1002_marker;
 
-	if (cifs_rdma_enabled(server) && server->smbd_conn) {
-		rc = smbd_send(server, num_rqst, rqst);
+	if (cifs_rdma_enabled(server)) {
+		/* return -EAGAIN when connecting or reconnecting */
+		rc = -EAGAIN;
+		if (server->smbd_conn)
+			rc = smbd_send(server, num_rqst, rqst);
 		goto smbd_done;
 	}