NFS41: fix error of setting blocklayoutdriver

After commit e38eb650 (NFS: set_pnfs_layoutdriver() from
nfs4_proc_fsinfo()), set_pnfs_layoutdriver() is called inside
nfs4_proc_fsinfo(), but pnfs_blksize is not set. It causes setting
blocklayoutdriver failure and pnfsblock mount failure.

Cc: stable <stable@vger.kernel.org> [since v3.5]
Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/client.c

@@ -849,7 +849,6 @@ static void nfs_server_set_fsinfo(struct nfs_server *server,
 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
 		server->wsize = NFS_MAX_FILE_IO_SIZE;
 	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
-	server->pnfs_blksize = fsinfo->blksize;
 
 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
 

fs/nfs/nfs4proc.c

@@ -3402,8 +3402,11 @@ static int nfs4_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle, s
 
 	nfs_fattr_init(fsinfo->fattr);
 	error = nfs4_do_fsinfo(server, fhandle, fsinfo);
-	if (error == 0)
+	if (error == 0) {
+		/* block layout checks this! */
+		server->pnfs_blksize = fsinfo->blksize;
 		set_pnfs_layoutdriver(server, fhandle, fsinfo->layouttype);
+	}
 
 	return error;
 }