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 * Written by Koji Sato. 17 */ 18 19 #ifndef _NILFS_BTREE_H 20 #define _NILFS_BTREE_H 21 22 #include <linux/types.h> 23 #include <linux/buffer_head.h> 24 #include <linux/list.h> 25 #include <linux/nilfs2_ondisk.h> /* nilfs_btree_node */ 26 #include "btnode.h" 27 #include "bmap.h" 28 29 /** 30 * struct nilfs_btree_path - A path on which B-tree operations are executed 31 * @bp_bh: buffer head of node block 32 * @bp_sib_bh: buffer head of sibling node block 33 * @bp_index: index of child node 34 * @bp_oldreq: ptr end request for old ptr 35 * @bp_newreq: ptr alloc request for new ptr 36 * @bp_op: rebalance operation 37 */ 38 struct nilfs_btree_path { 39 struct buffer_head *bp_bh; 40 struct buffer_head *bp_sib_bh; 41 int bp_index; 42 union nilfs_bmap_ptr_req bp_oldreq; 43 union nilfs_bmap_ptr_req bp_newreq; 44 struct nilfs_btnode_chkey_ctxt bp_ctxt; 45 void (*bp_op)(struct nilfs_bmap *, struct nilfs_btree_path *, 46 int, __u64 *, __u64 *); 47 }; 48 49 #define NILFS_BTREE_ROOT_SIZE NILFS_BMAP_SIZE 50 #define NILFS_BTREE_ROOT_NCHILDREN_MAX \ 51 ((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \ 52 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) 53 #define NILFS_BTREE_ROOT_NCHILDREN_MIN 0 54 #define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64)) 55 #define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) \ 56 (((nodesize) - sizeof(struct nilfs_btree_node) - \ 57 NILFS_BTREE_NODE_EXTRA_PAD_SIZE) / \ 58 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) 59 #define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize) \ 60 ((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1) 61 #define NILFS_BTREE_KEY_MIN ((__u64)0) 62 #define NILFS_BTREE_KEY_MAX (~(__u64)0) 63 64 extern struct kmem_cache *nilfs_btree_path_cache; 65 66 int nilfs_btree_init(struct nilfs_bmap *); 67 int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64, 68 const __u64 *, const __u64 *, int); 69 void nilfs_btree_init_gc(struct nilfs_bmap *); 70 71 int nilfs_btree_broken_node_block(struct buffer_head *bh); 72 73 #endif /* _NILFS_BTREE_H */ 74