1/*
2 *  linux/fs/hfs/btree.h
3 *
4 * Copyright (C) 2001
5 * Brad Boyer (flar@allandria.com)
6 * (C) 2003 Ardis Technologies <roman@ardistech.com>
7 */
8
9#include "hfs_fs.h"
10
11typedef int (*btree_keycmp)(const btree_key *, const btree_key *);
12
13#define NODE_HASH_SIZE  256
14
15/* A HFS BTree held in memory */
16struct hfs_btree {
17	struct super_block *sb;
18	struct inode *inode;
19	btree_keycmp keycmp;
20
21	u32 cnid;
22	u32 root;
23	u32 leaf_count;
24	u32 leaf_head;
25	u32 leaf_tail;
26	u32 node_count;
27	u32 free_nodes;
28	u32 attributes;
29
30	unsigned int node_size;
31	unsigned int node_size_shift;
32	unsigned int max_key_len;
33	unsigned int depth;
34
35	//unsigned int map1_size, map_size;
36	struct semaphore tree_lock;
37
38	unsigned int pages_per_bnode;
39	spinlock_t hash_lock;
40	struct hfs_bnode *node_hash[NODE_HASH_SIZE];
41	int node_hash_cnt;
42};
43
44/* A HFS BTree node in memory */
45struct hfs_bnode {
46	struct hfs_btree *tree;
47
48	u32 prev;
49	u32 this;
50	u32 next;
51	u32 parent;
52
53	u16 num_recs;
54	u8 type;
55	u8 height;
56
57	struct hfs_bnode *next_hash;
58	unsigned long flags;
59	wait_queue_head_t lock_wq;
60	atomic_t refcnt;
61	unsigned int page_offset;
62	struct page *page[0];
63};
64
65#define HFS_BNODE_ERROR		0
66#define HFS_BNODE_NEW		1
67#define HFS_BNODE_DELETED	2
68
69struct hfs_find_data {
70	btree_key *key;
71	btree_key *search_key;
72	struct hfs_btree *tree;
73	struct hfs_bnode *bnode;
74	int record;
75	int keyoffset, keylength;
76	int entryoffset, entrylength;
77};
78
79
80/* btree.c */
81extern struct hfs_btree *hfs_btree_open(struct super_block *, u32, btree_keycmp);
82extern void hfs_btree_close(struct hfs_btree *);
83extern void hfs_btree_write(struct hfs_btree *);
84extern struct hfs_bnode * hfs_bmap_alloc(struct hfs_btree *);
85extern void hfs_bmap_free(struct hfs_bnode *node);
86
87/* bnode.c */
88extern void hfs_bnode_read(struct hfs_bnode *, void *, int, int);
89extern u16 hfs_bnode_read_u16(struct hfs_bnode *, int);
90extern u8 hfs_bnode_read_u8(struct hfs_bnode *, int);
91extern void hfs_bnode_read_key(struct hfs_bnode *, void *, int);
92extern void hfs_bnode_write(struct hfs_bnode *, void *, int, int);
93extern void hfs_bnode_write_u16(struct hfs_bnode *, int, u16);
94extern void hfs_bnode_write_u8(struct hfs_bnode *, int, u8);
95extern void hfs_bnode_clear(struct hfs_bnode *, int, int);
96extern void hfs_bnode_copy(struct hfs_bnode *, int,
97			   struct hfs_bnode *, int, int);
98extern void hfs_bnode_move(struct hfs_bnode *, int, int, int);
99extern void hfs_bnode_dump(struct hfs_bnode *);
100extern void hfs_bnode_unlink(struct hfs_bnode *);
101extern struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *, u32);
102extern struct hfs_bnode *hfs_bnode_find(struct hfs_btree *, u32);
103extern void hfs_bnode_unhash(struct hfs_bnode *);
104extern void hfs_bnode_free(struct hfs_bnode *);
105extern struct hfs_bnode *hfs_bnode_create(struct hfs_btree *, u32);
106extern void hfs_bnode_get(struct hfs_bnode *);
107extern void hfs_bnode_put(struct hfs_bnode *);
108
109/* brec.c */
110extern u16 hfs_brec_lenoff(struct hfs_bnode *, u16, u16 *);
111extern u16 hfs_brec_keylen(struct hfs_bnode *, u16);
112extern int hfs_brec_insert(struct hfs_find_data *, void *, int);
113extern int hfs_brec_remove(struct hfs_find_data *);
114
115/* bfind.c */
116extern int hfs_find_init(struct hfs_btree *, struct hfs_find_data *);
117extern void hfs_find_exit(struct hfs_find_data *);
118extern int __hfs_brec_find(struct hfs_bnode *, struct hfs_find_data *);
119extern int hfs_brec_find(struct hfs_find_data *);
120extern int hfs_brec_read(struct hfs_find_data *, void *, int);
121extern int hfs_brec_goto(struct hfs_find_data *, int);
122
123
124struct hfs_bnode_desc {
125	__be32 next;		/* (V) Number of the next node at this level */
126	__be32 prev;		/* (V) Number of the prev node at this level */
127	u8 type;		/* (F) The type of node */
128	u8 height;		/* (F) The level of this node (leaves=1) */
129	__be16 num_recs;	/* (V) The number of records in this node */
130	u16 reserved;
131} __packed;
132
133#define HFS_NODE_INDEX	0x00	/* An internal (index) node */
134#define HFS_NODE_HEADER	0x01	/* The tree header node (node 0) */
135#define HFS_NODE_MAP	0x02	/* Holds part of the bitmap of used nodes */
136#define HFS_NODE_LEAF	0xFF	/* A leaf (ndNHeight==1) node */
137
138struct hfs_btree_header_rec {
139	__be16 depth;		/* (V) The number of levels in this B-tree */
140	__be32 root;		/* (V) The node number of the root node */
141	__be32 leaf_count;	/* (V) The number of leaf records */
142	__be32 leaf_head;	/* (V) The number of the first leaf node */
143	__be32 leaf_tail;	/* (V) The number of the last leaf node */
144	__be16 node_size;	/* (F) The number of bytes in a node (=512) */
145	__be16 max_key_len;	/* (F) The length of a key in an index node */
146	__be32 node_count;	/* (V) The total number of nodes */
147	__be32 free_nodes;	/* (V) The number of unused nodes */
148	u16 reserved1;
149	__be32 clump_size;	/* (F) clump size. not usually used. */
150	u8 btree_type;		/* (F) BTree type */
151	u8 reserved2;
152	__be32 attributes;	/* (F) attributes */
153	u32 reserved3[16];
154} __packed;
155
156#define HFS_NODE_INDEX	0x00	/* An internal (index) node */
157#define HFS_NODE_HEADER	0x01	/* The tree header node (node 0) */
158#define HFS_NODE_MAP		0x02	/* Holds part of the bitmap of used nodes */
159#define HFS_NODE_LEAF		0xFF	/* A leaf (ndNHeight==1) node */
160
161#define BTREE_ATTR_BADCLOSE	0x00000001	/* b-tree not closed properly. not
162						   used by hfsplus. */
163#define HFS_TREE_BIGKEYS	0x00000002	/* key length is u16 instead of u8.
164						   used by hfsplus. */
165#define HFS_TREE_VARIDXKEYS	0x00000004	/* variable key length instead of
166						   max key length. use din catalog
167						   b-tree but not in extents
168						   b-tree (hfsplus). */
169