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 /** 34 * struct nilfs_btree_path - A path on which B-tree operations are executed 35 * @bp_bh: buffer head of node block 36 * @bp_sib_bh: buffer head of sibling node block 37 * @bp_index: index of child node 38 * @bp_oldreq: ptr end request for old ptr 39 * @bp_newreq: ptr alloc request for new ptr 40 * @bp_op: rebalance operation 41 */ 42 struct nilfs_btree_path { 43 struct buffer_head *bp_bh; 44 struct buffer_head *bp_sib_bh; 45 int bp_index; 46 union nilfs_bmap_ptr_req bp_oldreq; 47 union nilfs_bmap_ptr_req bp_newreq; 48 struct nilfs_btnode_chkey_ctxt bp_ctxt; 49 void (*bp_op)(struct nilfs_bmap *, struct nilfs_btree_path *, 50 int, __u64 *, __u64 *); 51 }; 52 53 #define NILFS_BTREE_ROOT_SIZE NILFS_BMAP_SIZE 54 #define NILFS_BTREE_ROOT_NCHILDREN_MAX \ 55 ((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \ 56 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) 57 #define NILFS_BTREE_ROOT_NCHILDREN_MIN 0 58 #define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64)) 59 #define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) \ 60 (((nodesize) - sizeof(struct nilfs_btree_node) - \ 61 NILFS_BTREE_NODE_EXTRA_PAD_SIZE) / \ 62 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) 63 #define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize) \ 64 ((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1) 65 #define NILFS_BTREE_KEY_MIN ((__u64)0) 66 #define NILFS_BTREE_KEY_MAX (~(__u64)0) 67 68 extern struct kmem_cache *nilfs_btree_path_cache; 69 70 int nilfs_btree_init(struct nilfs_bmap *); 71 int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64, 72 const __u64 *, const __u64 *, int); 73 void nilfs_btree_init_gc(struct nilfs_bmap *); 74 75 int nilfs_btree_broken_node_block(struct buffer_head *bh); 76 77 #endif /* _NILFS_BTREE_H */ 78