1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * NILFS B-tree. 4 * 5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 6 * 7 * Written by Koji Sato. 8 */ 9 10 #ifndef _NILFS_BTREE_H 11 #define _NILFS_BTREE_H 12 13 #include <linux/types.h> 14 #include <linux/buffer_head.h> 15 #include <linux/list.h> 16 #include <linux/nilfs2_ondisk.h> /* nilfs_btree_node */ 17 #include "btnode.h" 18 #include "bmap.h" 19 20 /** 21 * struct nilfs_btree_path - A path on which B-tree operations are executed 22 * @bp_bh: buffer head of node block 23 * @bp_sib_bh: buffer head of sibling node block 24 * @bp_index: index of child node 25 * @bp_oldreq: ptr end request for old ptr 26 * @bp_newreq: ptr alloc request for new ptr 27 * @bp_ctxt: context information for changing the key of a b-tree node block 28 * @bp_op: rebalance operation 29 */ 30 struct nilfs_btree_path { 31 struct buffer_head *bp_bh; 32 struct buffer_head *bp_sib_bh; 33 int bp_index; 34 union nilfs_bmap_ptr_req bp_oldreq; 35 union nilfs_bmap_ptr_req bp_newreq; 36 struct nilfs_btnode_chkey_ctxt bp_ctxt; 37 void (*bp_op)(struct nilfs_bmap *, struct nilfs_btree_path *, 38 int, __u64 *, __u64 *); 39 }; 40 41 #define NILFS_BTREE_ROOT_SIZE NILFS_BMAP_SIZE 42 #define NILFS_BTREE_ROOT_NCHILDREN_MAX \ 43 ((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \ 44 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) 45 #define NILFS_BTREE_ROOT_NCHILDREN_MIN 0 46 #define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64)) 47 #define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) \ 48 (((nodesize) - sizeof(struct nilfs_btree_node) - \ 49 NILFS_BTREE_NODE_EXTRA_PAD_SIZE) / \ 50 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) 51 #define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize) \ 52 ((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1) 53 #define NILFS_BTREE_KEY_MIN ((__u64)0) 54 #define NILFS_BTREE_KEY_MAX (~(__u64)0) 55 56 extern struct kmem_cache *nilfs_btree_path_cache; 57 58 int nilfs_btree_init(struct nilfs_bmap *); 59 int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64, 60 const __u64 *, const __u64 *, int); 61 void nilfs_btree_init_gc(struct nilfs_bmap *); 62 63 int nilfs_btree_broken_node_block(struct buffer_head *bh); 64 65 #endif /* _NILFS_BTREE_H */ 66