fs/hfs/btree.h

   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). */