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_op: rebalance operation
28 */
29struct nilfs_btree_path {
30 struct buffer_head *bp_bh;
31 struct buffer_head *bp_sib_bh;
32 int bp_index;
33 union nilfs_bmap_ptr_req bp_oldreq;
34 union nilfs_bmap_ptr_req bp_newreq;
35 struct nilfs_btnode_chkey_ctxt bp_ctxt;
36 void (*bp_op)(struct nilfs_bmap *, struct nilfs_btree_path *,
37 int, __u64 *, __u64 *);
38};
39
40#define NILFS_BTREE_ROOT_SIZE NILFS_BMAP_SIZE
41#define NILFS_BTREE_ROOT_NCHILDREN_MAX \
42 ((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \
43 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
44#define NILFS_BTREE_ROOT_NCHILDREN_MIN 0
45#define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64))
46#define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) \
47 (((nodesize) - sizeof(struct nilfs_btree_node) - \
48 NILFS_BTREE_NODE_EXTRA_PAD_SIZE) / \
49 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
50#define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize) \
51 ((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1)
52#define NILFS_BTREE_KEY_MIN ((__u64)0)
53#define NILFS_BTREE_KEY_MAX (~(__u64)0)
54
55extern struct kmem_cache *nilfs_btree_path_cache;
56
57int nilfs_btree_init(struct nilfs_bmap *);
58int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64,
59 const __u64 *, const __u64 *, int);
60void nilfs_btree_init_gc(struct nilfs_bmap *);
61
62int nilfs_btree_broken_node_block(struct buffer_head *bh);
63
64#endif /* _NILFS_BTREE_H */
65

source code of linux/fs/nilfs2/btree.h