LXR linux/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 mutex 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 BTREE_ATTR_BADCLOSE     0x00000001      /* b-tree not closed properly. not
 157                                                   used by hfsplus. */
 158#define HFS_TREE_BIGKEYS        0x00000002      /* key length is u16 instead of u8.
 159                                                   used by hfsplus. */
 160#define HFS_TREE_VARIDXKEYS     0x00000004      /* variable key length instead of
 161                                                   max key length. use din catalog
 162                                                   b-tree but not in extents
 163                                                   b-tree (hfsplus). */
 164