Root/fs/hfs/btree.h

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

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