NFS: "[no]resvport" mount option changes mountd client too

If the admin has specified the "noresvport" option for an NFS mount
point, the kernel's NFS client uses an unprivileged source port for
the main NFS transport.  The kernel's mountd client should use an
unprivileged port in this case as well.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/internal.h

@@ -72,6 +72,7 @@ struct nfs_mount_request {
 	u32			version;
 	unsigned short		protocol;
 	struct nfs_fh		*fh;
+	int			noresvport;
 };
 
 extern int nfs_mount(struct nfs_mount_request *info);

fs/nfs/mount_clnt.c

@@ -50,7 +50,6 @@ int nfs_mount(struct nfs_mount_request *info)
 		.program	= &mnt_program,
 		.version	= info->version,
 		.authflavor	= RPC_AUTH_UNIX,
-		.flags		= 0,
 	};
 	struct rpc_clnt		*mnt_clnt;
 	int			status;
@@ -59,6 +58,9 @@ int nfs_mount(struct nfs_mount_request *info)
 		(info->hostname ? info->hostname : "server"),
 			info->dirpath);
 
+	if (info->noresvport)
+		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
+
 	mnt_clnt = rpc_create(&args);
 	if (IS_ERR(mnt_clnt))
 		goto out_clnt_err;

fs/nfs/super.c

@@ -1345,6 +1345,7 @@ static int nfs_try_mount(struct nfs_parsed_mount_data *args,
 		.dirpath	= args->nfs_server.export_path,
 		.protocol	= args->mount_server.protocol,
 		.fh		= root_fh,
+		.noresvport	= args->flags & NFS_MOUNT_NORESVPORT,
 	};
 	int status;