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