1 /* 2 * btree.h - NILFS B-tree. 3 * 4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * Written by Koji Sato <koji@osrg.net>. 21 */ 22 23 #ifndef _NILFS_BTREE_H 24 #define _NILFS_BTREE_H 25 26 #include <linux/types.h> 27 #include <linux/buffer_head.h> 28 #include <linux/list.h> 29 #include <linux/nilfs2_fs.h> 30 #include "btnode.h" 31 #include "bmap.h" 32 33 struct nilfs_btree; 34 struct nilfs_btree_path; 35 36 /** 37 * struct nilfs_btree - B-tree structure 38 * @bt_bmap: bmap base structure 39 */ 40 struct nilfs_btree { 41 struct nilfs_bmap bt_bmap; 42 }; 43 44 45 #define NILFS_BTREE_ROOT_SIZE NILFS_BMAP_SIZE 46 #define NILFS_BTREE_ROOT_NCHILDREN_MAX \ 47 ((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \ 48 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) 49 #define NILFS_BTREE_ROOT_NCHILDREN_MIN 0 50 #define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64)) 51 #define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) \ 52 (((nodesize) - sizeof(struct nilfs_btree_node) - \ 53 NILFS_BTREE_NODE_EXTRA_PAD_SIZE) / \ 54 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) 55 #define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize) \ 56 ((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1) 57 #define NILFS_BTREE_KEY_MIN ((__u64)0) 58 #define NILFS_BTREE_KEY_MAX (~(__u64)0) 59 60 61 int nilfs_btree_path_cache_init(void); 62 void nilfs_btree_path_cache_destroy(void); 63 int nilfs_btree_init(struct nilfs_bmap *); 64 int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64, 65 const __u64 *, const __u64 *, int); 66 void nilfs_btree_init_gc(struct nilfs_bmap *); 67 68 #endif /* _NILFS_BTREE_H */ 69