NFSv4.1: add MDS mount DS only check
The DS only role cannot be used to mount.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 280d41f6..d5c5bdf 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -1453,6 +1453,10 @@
BUG_ON(!server->nfs_client->rpc_ops);
BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
+ /* data servers support only a subset of NFSv4.1 */
+ if (is_ds_only_client(server->nfs_client))
+ return -EPROTONOSUPPORT;
+
fattr = nfs_alloc_fattr();
if (fattr == NULL)
return -ENOMEM;