nilfs_btree_node_init
nilfs_btree_node_init(sib, 0, level, 0, ncblk, NULL, NULL);
nilfs_btree_node_init((struct nilfs_btree_node *)bh->b_data,
nilfs_btree_node_init(node, 0, 1, n, ncblk, keys, ptrs);
nilfs_btree_node_init(node, NILFS_BTREE_NODE_ROOT, 2, 1,
nilfs_btree_node_init(node, NILFS_BTREE_NODE_ROOT, 1, n,