NFSv4.1/pnfs: Play safe w.r.t. close() races when return-on-close is set

If we have an OPEN_DOWNGRADE and CLOSE race with one another, we want
to ensure that the layout is forgotten by the client, so that we
start afresh with a new layoutget.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

fs/nfs/nfs4proc.c

@@ -2661,7 +2661,7 @@ static void nfs4_close_done(struct rpc_task *task, void *data)
 	switch (task->tk_status) {
 		case 0:
 			res_stateid = &calldata->res.stateid;
-			if (calldata->arg.fmode == 0 && calldata->roc)
+			if (calldata->roc)
 				pnfs_roc_set_barrier(state->inode,
 						     calldata->roc_barrier);
 			renew_lease(server, calldata->timestamp);
@@ -2735,11 +2735,11 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data)
 		goto out_no_action;
 	}
 
-	if (calldata->arg.fmode == 0) {
+	if (calldata->arg.fmode == 0)
 		task->tk_msg.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CLOSE];
-		if (calldata->roc)
-			pnfs_roc_get_barrier(inode, &calldata->roc_barrier);
-	}
+	if (calldata->roc)
+		pnfs_roc_get_barrier(inode, &calldata->roc_barrier);
+
 	calldata->arg.share_access =
 		nfs4_map_atomic_open_share(NFS_SERVER(inode),
 				calldata->arg.fmode, 0);