NFSv4: Fix OPEN_DOWNGRADE error handling

If OPEN_DOWNGRADE returns a state error, then we want to initiate
state recovery in addition to marking the stateid as closed.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/nfs4proc.c

@@ -3399,7 +3399,9 @@ static void nfs4_close_done(struct rpc_task *task, void *data)
 					task->tk_msg.rpc_cred);
 			/* Fallthrough */
 		case -NFS4ERR_BAD_STATEID:
+			if (calldata->arg.fmode == 0)
 				break;
+			/* Fallthrough */
 		default:
 			task->tk_status = nfs4_async_handle_exception(task,
 					server, task->tk_status, &exception);