usr/src/grub/grub-0.97/stage2/zfs-include/zap_leaf.h

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 1999,2000,2001,2002,2003,2004  Free Software Foundation, Inc.
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19 /*
  20  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  21  * Use is subject to license terms.
  22  */
  23
  24 #ifndef _SYS_ZAP_LEAF_H
  25 #define _SYS_ZAP_LEAF_H
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #define ZAP_LEAF_MAGIC 0x2AB1EAF
  30
  31 /* chunk size = 24 bytes */
  32 #define ZAP_LEAF_CHUNKSIZE 24
  33
  34 /*
  35  * The amount of space within the chunk available for the array is:
  36  * chunk size - space for type (1) - space for next pointer (2)
  37  */
  38 #define ZAP_LEAF_ARRAY_BYTES (ZAP_LEAF_CHUNKSIZE - 3)
  39
  40 typedef enum zap_chunk_type {
  41         ZAP_CHUNK_FREE = 253,
  42         ZAP_CHUNK_ENTRY = 252,
  43         ZAP_CHUNK_ARRAY = 251,
  44         ZAP_CHUNK_TYPE_MAX = 250
  45 } zap_chunk_type_t;
  46
  47 /*
  48  * TAKE NOTE:
  49  * If zap_leaf_phys_t is modified, zap_leaf_byteswap() must be modified.
  50  */
  51 typedef struct zap_leaf_phys {
  52         struct zap_leaf_header {
  53                 uint64_t lh_block_type;         /* ZBT_LEAF */
  54                 uint64_t lh_pad1;
  55                 uint64_t lh_prefix;             /* hash prefix of this leaf */
  56                 uint32_t lh_magic;              /* ZAP_LEAF_MAGIC */
  57                 uint16_t lh_nfree;              /* number free chunks */
  58                 uint16_t lh_nentries;           /* number of entries */
  59                 uint16_t lh_prefix_len;         /* num bits used to id this */
  60
  61 /* above is accessable to zap, below is zap_leaf private */
  62
  63                 uint16_t lh_freelist;           /* chunk head of free list */
  64                 uint8_t lh_pad2[12];
  65         } l_hdr; /* 2 24-byte chunks */
  66
  67         /*
  68          * The header is followed by a hash table with
  69          * ZAP_LEAF_HASH_NUMENTRIES(zap) entries.  The hash table is
  70          * followed by an array of ZAP_LEAF_NUMCHUNKS(zap)
  71          * zap_leaf_chunk structures.  These structures are accessed
  72          * with the ZAP_LEAF_CHUNK() macro.
  73          */
  74
  75         uint16_t l_hash[1];
  76 } zap_leaf_phys_t;
  77
  78 typedef union zap_leaf_chunk {
  79         struct zap_leaf_entry {
  80                 uint8_t le_type;                /* always ZAP_CHUNK_ENTRY */
  81                 uint8_t le_int_size;            /* size of ints */
  82                 uint16_t le_next;               /* next entry in hash chain */
  83                 uint16_t le_name_chunk;         /* first chunk of the name */
  84                 uint16_t le_name_length;        /* bytes in name, incl null */
  85                 uint16_t le_value_chunk;        /* first chunk of the value */
  86                 uint16_t le_value_length;       /* value length in ints */
  87                 uint32_t le_cd;                 /* collision differentiator */
  88                 uint64_t le_hash;               /* hash value of the name */
  89         } l_entry;
  90         struct zap_leaf_array {
  91                 uint8_t la_type;                /* always ZAP_CHUNK_ARRAY */
  92                 uint8_t la_array[ZAP_LEAF_ARRAY_BYTES];
  93                 uint16_t la_next;               /* next blk or CHAIN_END */
  94         } l_array;
  95         struct zap_leaf_free {
  96                 uint8_t lf_type;                /* always ZAP_CHUNK_FREE */
  97                 uint8_t lf_pad[ZAP_LEAF_ARRAY_BYTES];
  98                 uint16_t lf_next;       /* next in free list, or CHAIN_END */
  99         } l_free;
 100 } zap_leaf_chunk_t;
 101
 102 #endif /* _SYS_ZAP_LEAF_H */