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
  11 typedef int (*btree_keycmp)(const btree_key *, const btree_key *);
  12
  13 #define NODE_HASH_SIZE  256
  14
  15 /* A HFS BTree held in memory */
  16 struct 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 */
  45 struct 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
  69 struct 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 */
  81 extern struct hfs_btree *hfs_btree_open(struct super_block *, u32, btree_keycmp);
  82 extern void hfs_btree_close(struct hfs_btree *);
  83 extern void hfs_btree_write(struct hfs_btree *);
  84 extern struct hfs_bnode * hfs_bmap_alloc(struct hfs_btree *);
  85 extern void hfs_bmap_free(struct hfs_bnode *node);
  86
  87 /* bnode.c */
  88 extern void hfs_bnode_read(struct hfs_bnode *, void *, int, int);
  89 extern u16 hfs_bnode_read_u16(struct hfs_bnode *, int);
  90 extern u8 hfs_bnode_read_u8(struct hfs_bnode *, int);
  91 extern void hfs_bnode_read_key(struct hfs_bnode *, void *, int);
  92 extern void hfs_bnode_write(struct hfs_bnode *, void *, int, int);
  93 extern void hfs_bnode_write_u16(struct hfs_bnode *, int, u16);
  94 extern void hfs_bnode_write_u8(struct hfs_bnode *, int, u8);
  95 extern void hfs_bnode_clear(struct hfs_bnode *, int, int);
  96 extern void hfs_bnode_copy(struct hfs_bnode *, int,
  97                            struct hfs_bnode *, int, int);
  98 extern void hfs_bnode_move(struct hfs_bnode *, int, int, int);
  99 extern void hfs_bnode_dump(struct hfs_bnode *);
 100 extern void hfs_bnode_unlink(struct hfs_bnode *);
 101 extern struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *, u32);
 102 extern struct hfs_bnode *hfs_bnode_find(struct hfs_btree *, u32);
 103 extern void hfs_bnode_unhash(struct hfs_bnode *);
 104 extern void hfs_bnode_free(struct hfs_bnode *);
 105 extern struct hfs_bnode *hfs_bnode_create(struct hfs_btree *, u32);
 106 extern void hfs_bnode_get(struct hfs_bnode *);
 107 extern void hfs_bnode_put(struct hfs_bnode *);
 108
 109 /* brec.c */
 110 extern u16 hfs_brec_lenoff(struct hfs_bnode *, u16, u16 *);
 111 extern u16 hfs_brec_keylen(struct hfs_bnode *, u16);
 112 extern int hfs_brec_insert(struct hfs_find_data *, void *, int);
 113 extern int hfs_brec_remove(struct hfs_find_data *);
 114 extern struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *);
 115 extern int hfs_brec_update_parent(struct hfs_find_data *);
 116 extern int hfs_btree_inc_height(struct hfs_btree *);
 117
 118 /* bfind.c */
 119 extern int hfs_find_init(struct hfs_btree *, struct hfs_find_data *);
 120 extern void hfs_find_exit(struct hfs_find_data *);
 121 extern int __hfs_brec_find(struct hfs_bnode *, struct hfs_find_data *);
 122 extern int hfs_brec_find(struct hfs_find_data *);
 123 extern int hfs_brec_read(struct hfs_find_data *, void *, int);
 124 extern int hfs_brec_goto(struct hfs_find_data *, int);
 125
 126
 127 struct hfs_bnode_desc {
 128         __be32 next;            /* (V) Number of the next node at this level */
 129         __be32 prev;            /* (V) Number of the prev node at this level */
 130         u8 type;                /* (F) The type of node */
 131         u8 height;              /* (F) The level of this node (leaves=1) */
 132         __be16 num_recs;        /* (V) The number of records in this node */
 133         u16 reserved;
 134 } __packed;
 135
 136 #define HFS_NODE_INDEX  0x00    /* An internal (index) node */
 137 #define HFS_NODE_HEADER 0x01    /* The tree header node (node 0) */
 138 #define HFS_NODE_MAP    0x02    /* Holds part of the bitmap of used nodes */
 139 #define HFS_NODE_LEAF   0xFF    /* A leaf (ndNHeight==1) node */
 140
 141 struct hfs_btree_header_rec {
 142         __be16 depth;           /* (V) The number of levels in this B-tree */
 143         __be32 root;            /* (V) The node number of the root node */
 144         __be32 leaf_count;      /* (V) The number of leaf records */
 145         __be32 leaf_head;       /* (V) The number of the first leaf node */
 146         __be32 leaf_tail;       /* (V) The number of the last leaf node */
 147         __be16 node_size;       /* (F) The number of bytes in a node (=512) */
 148         __be16 max_key_len;     /* (F) The length of a key in an index node */
 149         __be32 node_count;      /* (V) The total number of nodes */
 150         __be32 free_nodes;      /* (V) The number of unused nodes */
 151         u16 reserved1;
 152         __be32 clump_size;      /* (F) clump size. not usually used. */
 153         u8 btree_type;          /* (F) BTree type */
 154         u8 reserved2;
 155         __be32 attributes;      /* (F) attributes */
 156         u32 reserved3[16];
 157 } __packed;
 158
 159 #define HFS_NODE_INDEX  0x00    /* An internal (index) node */
 160 #define HFS_NODE_HEADER 0x01    /* The tree header node (node 0) */
 161 #define HFS_NODE_MAP            0x02    /* Holds part of the bitmap of used nodes */
 162 #define HFS_NODE_LEAF           0xFF    /* A leaf (ndNHeight==1) node */
 163
 164 #define BTREE_ATTR_BADCLOSE     0x00000001      /* b-tree not closed properly. not
 165                                                    used by hfsplus. */
 166 #define HFS_TREE_BIGKEYS        0x00000002      /* key length is u16 instead of u8.
 167                                                    used by hfsplus. */
 168 #define HFS_TREE_VARIDXKEYS     0x00000004      /* variable key length instead of
 169                                                    max key length. use din catalog
 170                                                    b-tree but not in extents
 171                                                    b-tree (hfsplus). */