1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * linux/fs/hfs/btree.h
4 *
5 * Copyright (C) 2001
6 * Brad Boyer (flar@allandria.com)
7 * (C) 2003 Ardis Technologies <roman@ardistech.com>
8 */
9
10 #include "hfs_fs.h"
11
12 typedef int (*btree_keycmp)(const btree_key *, const btree_key *);
13
14 #define NODE_HASH_SIZE 256
15
16 /* B-tree mutex nested subclasses */
17 enum hfs_btree_mutex_classes {
18 CATALOG_BTREE_MUTEX,
19 EXTENTS_BTREE_MUTEX,
20 ATTR_BTREE_MUTEX,
21 };
22
23 /* A HFS BTree held in memory */
24 struct hfs_btree {
25 struct super_block *sb;
26 struct inode *inode;
27 btree_keycmp keycmp;
28
29 u32 cnid;
30 u32 root;
31 u32 leaf_count;
32 u32 leaf_head;
33 u32 leaf_tail;
34 u32 node_count;
35 u32 free_nodes;
36 u32 attributes;
37
38 unsigned int node_size;
39 unsigned int node_size_shift;
40 unsigned int max_key_len;
41 unsigned int depth;
42
43 //unsigned int map1_size, map_size;
44 struct mutex tree_lock;
45
46 unsigned int pages_per_bnode;
47 spinlock_t hash_lock;
48 struct hfs_bnode *node_hash[NODE_HASH_SIZE];
49 int node_hash_cnt;
50 };
51
52 /* A HFS BTree node in memory */
53 struct hfs_bnode {
54 struct hfs_btree *tree;
55
56 u32 prev;
57 u32 this;
58 u32 next;
59 u32 parent;
60
61 u16 num_recs;
62 u8 type;
63 u8 height;
64
65 struct hfs_bnode *next_hash;
66 unsigned long flags;
67 wait_queue_head_t lock_wq;
68 atomic_t refcnt;
69 unsigned int page_offset;
70 struct page *page[];
71 };
72
73 #define HFS_BNODE_ERROR 0
74 #define HFS_BNODE_NEW 1
75 #define HFS_BNODE_DELETED 2
76
77 struct hfs_find_data {
78 btree_key *key;
79 btree_key *search_key;
80 struct hfs_btree *tree;
81 struct hfs_bnode *bnode;
82 int record;
83 int keyoffset, keylength;
84 int entryoffset, entrylength;
85 };
86
87
88 /* btree.c */
89 extern struct hfs_btree *hfs_btree_open(struct super_block *, u32, btree_keycmp);
90 extern void hfs_btree_close(struct hfs_btree *);
91 extern void hfs_btree_write(struct hfs_btree *);
92 extern int hfs_bmap_reserve(struct hfs_btree *, int);
93 extern struct hfs_bnode * hfs_bmap_alloc(struct hfs_btree *);
94 extern void hfs_bmap_free(struct hfs_bnode *node);
95
96 /* bnode.c */
97 extern void hfs_bnode_read(struct hfs_bnode *, void *, int, int);
98 extern u16 hfs_bnode_read_u16(struct hfs_bnode *, int);
99 extern u8 hfs_bnode_read_u8(struct hfs_bnode *, int);
100 extern void hfs_bnode_read_key(struct hfs_bnode *, void *, int);
101 extern void hfs_bnode_write(struct hfs_bnode *, void *, int, int);
102 extern void hfs_bnode_write_u16(struct hfs_bnode *, int, u16);
103 extern void hfs_bnode_write_u8(struct hfs_bnode *, int, u8);
104 extern void hfs_bnode_clear(struct hfs_bnode *, int, int);
105 extern void hfs_bnode_copy(struct hfs_bnode *, int,
106 struct hfs_bnode *, int, int);
107 extern void hfs_bnode_move(struct hfs_bnode *, int, int, int);
108 extern void hfs_bnode_dump(struct hfs_bnode *);
109 extern void hfs_bnode_unlink(struct hfs_bnode *);
110 extern struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *, u32);
111 extern struct hfs_bnode *hfs_bnode_find(struct hfs_btree *, u32);
112 extern void hfs_bnode_unhash(struct hfs_bnode *);
113 extern void hfs_bnode_free(struct hfs_bnode *);
114 extern struct hfs_bnode *hfs_bnode_create(struct hfs_btree *, u32);
115 extern void hfs_bnode_get(struct hfs_bnode *);
116 extern void hfs_bnode_put(struct hfs_bnode *);
117
118 /* brec.c */
119 extern u16 hfs_brec_lenoff(struct hfs_bnode *, u16, u16 *);
120 extern u16 hfs_brec_keylen(struct hfs_bnode *, u16);
121 extern int hfs_brec_insert(struct hfs_find_data *, void *, int);
122 extern int hfs_brec_remove(struct hfs_find_data *);
123
124 /* bfind.c */
125 extern int hfs_find_init(struct hfs_btree *, struct hfs_find_data *);
126 extern void hfs_find_exit(struct hfs_find_data *);
127 extern int __hfs_brec_find(struct hfs_bnode *, struct hfs_find_data *);
128 extern int hfs_brec_find(struct hfs_find_data *);
129 extern int hfs_brec_read(struct hfs_find_data *, void *, int);
130 extern int hfs_brec_goto(struct hfs_find_data *, int);
131
132
133 struct hfs_bnode_desc {
134 __be32 next; /* (V) Number of the next node at this level */
135 __be32 prev; /* (V) Number of the prev node at this level */
136 u8 type; /* (F) The type of node */
137 u8 height; /* (F) The level of this node (leaves=1) */
138 __be16 num_recs; /* (V) The number of records in this node */
139 u16 reserved;
140 } __packed;
141
142 #define HFS_NODE_INDEX 0x00 /* An internal (index) node */
143 #define HFS_NODE_HEADER 0x01 /* The tree header node (node 0) */
144 #define HFS_NODE_MAP 0x02 /* Holds part of the bitmap of used nodes */
145 #define HFS_NODE_LEAF 0xFF /* A leaf (ndNHeight==1) node */
146
147 struct hfs_btree_header_rec {
148 __be16 depth; /* (V) The number of levels in this B-tree */
149 __be32 root; /* (V) The node number of the root node */
150 __be32 leaf_count; /* (V) The number of leaf records */
151 __be32 leaf_head; /* (V) The number of the first leaf node */
152 __be32 leaf_tail; /* (V) The number of the last leaf node */
153 __be16 node_size; /* (F) The number of bytes in a node (=512) */
154 __be16 max_key_len; /* (F) The length of a key in an index node */
155 __be32 node_count; /* (V) The total number of nodes */
156 __be32 free_nodes; /* (V) The number of unused nodes */
157 u16 reserved1;
158 __be32 clump_size; /* (F) clump size. not usually used. */
159 u8 btree_type; /* (F) BTree type */
160 u8 reserved2;
161 __be32 attributes; /* (F) attributes */
162 u32 reserved3[16];
163 } __packed;
164
165 #define BTREE_ATTR_BADCLOSE 0x00000001 /* b-tree not closed properly. not
166 used by hfsplus. */
167 #define HFS_TREE_BIGKEYS 0x00000002 /* key length is u16 instead of u8.
168 used by hfsplus. */
169 #define HFS_TREE_VARIDXKEYS 0x00000004 /* variable key length instead of
170 max key length. use din catalog
171 b-tree but not in extents
172 b-tree (hfsplus). */
173
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