NFS: Save the values of the "mount*=" mount options

Save the value of the mountproto= mountport= mountvers= and mountaddr=
options so that these values can be displayed later via
nfs_show_options().

This preserves the intent of the original mount options, should the file
system need to be remounted based on what's displayed in /proc/mounts.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/client.c

@@ -688,6 +688,16 @@ static int nfs_init_server(struct nfs_server *server,
 	if (error < 0)
 		goto error;
 
+	/* Preserve the values of mount_server-related mount options */
+	if (data->mount_server.addrlen) {
+		memcpy(&server->mountd_address, &data->mount_server.address,
+			data->mount_server.addrlen);
+		server->mountd_addrlen = data->mount_server.addrlen;
+	}
+	server->mountd_version = data->mount_server.version;
+	server->mountd_port = data->mount_server.port;
+	server->mountd_protocol = data->mount_server.protocol;
+
 	server->namelen  = data->namlen;
 	/* Create a client RPC handle for the NFSv3 ACL management interface */
 	nfs_init_server_aclclient(server);

include/linux/nfs_fs_sb.h

@@ -118,6 +118,13 @@ struct nfs_server {
 
 	atomic_t active; /* Keep trace of any activity to this server */
 	wait_queue_head_t active_wq;  /* Wait for any activity to stop  */
+
+	/* mountd-related mount options */
+	struct sockaddr_storage	mountd_address;
+	size_t			mountd_addrlen;
+	u32			mountd_version;
+	unsigned short		mountd_port;
+	unsigned short		mountd_protocol;
 };
 
 /* Server capabilities */