usr/src/grub/grub-0.97/stage2/zfs-include/spa.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 /*
  21  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  22  * Use is subject to license terms.
  23  */
  24
  25 /*
  26  * Copyright (c) 2013 by Delphix. All rights reserved.
  27  */
  28
  29 #ifndef _SYS_SPA_H
  30 #define _SYS_SPA_H
  31
  32 /*
  33  * General-purpose 32-bit and 64-bit bitfield encodings.
  34  */
  35 #define BF32_DECODE(x, low, len)        P2PHASE((x) >> (low), 1U << (len))
  36 #define BF64_DECODE(x, low, len)        P2PHASE((x) >> (low), 1ULL << (len))
  37 #define BF32_ENCODE(x, low, len)        (P2PHASE((x), 1U << (len)) << (low))
  38 #define BF64_ENCODE(x, low, len)        (P2PHASE((x), 1ULL << (len)) << (low))
  39
  40 #define BF32_GET(x, low, len)           BF32_DECODE(x, low, len)
  41 #define BF64_GET(x, low, len)           BF64_DECODE(x, low, len)
  42
  43 #define BF32_SET(x, low, len, val)      \
  44         ((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len))
  45 #define BF64_SET(x, low, len, val)      \
  46         ((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len))
  47
  48 #define BF32_GET_SB(x, low, len, shift, bias)   \
  49         ((BF32_GET(x, low, len) + (bias)) << (shift))
  50 #define BF64_GET_SB(x, low, len, shift, bias)   \
  51         ((BF64_GET(x, low, len) + (bias)) << (shift))
  52
  53 #define BF32_SET_SB(x, low, len, shift, bias, val)      \
  54         BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
  55 #define BF64_SET_SB(x, low, len, shift, bias, val)      \
  56         BF64_SET(x, low, len, ((val) >> (shift)) - (bias))
  57
  58 /*
  59  * We currently support nine block sizes, from 512 bytes to 128K.
  60  * We could go higher, but the benefits are near-zero and the cost
  61  * of COWing a giant block to modify one byte would become excessive.
  62  */
  63 #define SPA_MINBLOCKSHIFT       9
  64 #define SPA_MAXBLOCKSHIFT       17
  65 #define SPA_MINBLOCKSIZE        (1ULL << SPA_MINBLOCKSHIFT)
  66 #define SPA_MAXBLOCKSIZE        (1ULL << SPA_MAXBLOCKSHIFT)
  67
  68 #define SPA_BLOCKSIZES          (SPA_MAXBLOCKSHIFT - SPA_MINBLOCKSHIFT + 1)
  69
  70 /*
  71  * Size of block to hold the configuration data (a packed nvlist)
  72  */
  73 #define SPA_CONFIG_BLOCKSIZE    (1ULL << 14)
  74
  75 /*
  76  * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
  77  * The ASIZE encoding should be at least 64 times larger (6 more bits)
  78  * to support up to 4-way RAID-Z mirror mode with worst-case gang block
  79  * overhead, three DVAs per bp, plus one more bit in case we do anything
  80  * else that expands the ASIZE.
  81  */
  82 #define SPA_LSIZEBITS           16      /* LSIZE up to 32M (2^16 * 512) */
  83 #define SPA_PSIZEBITS           16      /* PSIZE up to 32M (2^16 * 512) */
  84 #define SPA_ASIZEBITS           24      /* ASIZE up to 64 times larger  */
  85
  86 /*
  87  * All SPA data is represented by 128-bit data virtual addresses (DVAs).
  88  * The members of the dva_t should be considered opaque outside the SPA.
  89  */
  90 typedef struct dva {
  91         uint64_t        dva_word[2];
  92 } dva_t;
  93
  94 /*
  95  * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
  96  */
  97 typedef struct zio_cksum {
  98         uint64_t        zc_word[4];
  99 } zio_cksum_t;
 100
 101 /*
 102  * Each block is described by its DVAs, time of birth, checksum, etc.
 103  * The word-by-word, bit-by-bit layout of the blkptr is as follows:
 104  *
 105  *      64      56      48      40      32      24      16      8       0
 106  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 107  * 0    |               vdev1           | GRID  |         ASIZE         |
 108  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 109  * 1    |G|                      offset1                                |
 110  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 111  * 2    |               vdev2           | GRID  |         ASIZE         |
 112  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 113  * 3    |G|                      offset2                                |
 114  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 115  * 4    |               vdev3           | GRID  |         ASIZE         |
 116  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 117  * 5    |G|                      offset3                                |
 118  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 119  * 6    |BDX|lvl| type  | cksum |E| comp|    PSIZE      |     LSIZE     |
 120  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 121  * 7    |                       padding                                 |
 122  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 123  * 8    |                       padding                                 |
 124  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 125  * 9    |                       physical birth txg                      |
 126  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 127  * a    |                       logical birth txg                       |
 128  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 129  * b    |                       fill count                              |
 130  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 131  * c    |                       checksum[0]                             |
 132  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 133  * d    |                       checksum[1]                             |
 134  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 135  * e    |                       checksum[2]                             |
 136  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 137  * f    |                       checksum[3]                             |
 138  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 139  *
 140  * Legend:
 141  *
 142  * vdev         virtual device ID
 143  * offset       offset into virtual device
 144  * LSIZE        logical size
 145  * PSIZE        physical size (after compression)
 146  * ASIZE        allocated size (including RAID-Z parity and gang block headers)
 147  * GRID         RAID-Z layout information (reserved for future use)
 148  * cksum        checksum function
 149  * comp         compression function
 150  * G            gang block indicator
 151  * B            byteorder (endianness)
 152  * D            dedup
 153  * X            encryption (on version 30, which is not supported)
 154  * E            blkptr_t contains embedded data
 155  * lvl          level of indirection
 156  * type         DMU object type
 157  * phys birth   txg of block allocation; zero if same as logical birth txg
 158  * log. birth   transaction group in which the block was logically born
 159  * fill count   number of non-zero blocks under this bp
 160  * checksum[4]  256-bit checksum of the data this bp describes
 161  */
 162 #define SPA_BLKPTRSHIFT 7               /* blkptr_t is 128 bytes        */
 163 #define SPA_DVAS_PER_BP 3               /* Number of DVAs in a bp       */
 164
 165 typedef struct blkptr {
 166         dva_t           blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
 167         uint64_t        blk_prop;       /* size, compression, type, etc     */
 168         uint64_t        blk_pad[2];     /* Extra space for the future       */
 169         uint64_t        blk_phys_birth; /* txg when block was allocated     */
 170         uint64_t        blk_birth;      /* transaction group at birth       */
 171         uint64_t        blk_fill;       /* fill count                       */
 172         zio_cksum_t     blk_cksum;      /* 256-bit checksum                 */
 173 } blkptr_t;
 174
 175 /*
 176  * Macros to get and set fields in a bp or DVA.
 177  */
 178 #define DVA_GET_ASIZE(dva)      \
 179         BF64_GET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, SPA_MINBLOCKSHIFT, 0)
 180 #define DVA_SET_ASIZE(dva, x)   \
 181         BF64_SET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, \
 182         SPA_MINBLOCKSHIFT, 0, x)
 183
 184 #define DVA_GET_GRID(dva)       BF64_GET((dva)->dva_word[0], 24, 8)
 185 #define DVA_SET_GRID(dva, x)    BF64_SET((dva)->dva_word[0], 24, 8, x)
 186
 187 #define DVA_GET_VDEV(dva)       BF64_GET((dva)->dva_word[0], 32, 32)
 188 #define DVA_SET_VDEV(dva, x)    BF64_SET((dva)->dva_word[0], 32, 32, x)
 189
 190 #define DVA_GET_OFFSET(dva)     \
 191         BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
 192 #define DVA_SET_OFFSET(dva, x)  \
 193         BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)
 194
 195 #define DVA_GET_GANG(dva)       BF64_GET((dva)->dva_word[1], 63, 1)
 196 #define DVA_SET_GANG(dva, x)    BF64_SET((dva)->dva_word[1], 63, 1, x)
 197
 198 #define BP_GET_LSIZE(bp)        \
 199         BF64_GET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1)
 200 #define BP_SET_LSIZE(bp, x)     \
 201         BF64_SET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x)
 202
 203 #define BP_GET_PSIZE(bp)        \
 204         BF64_GET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1)
 205 #define BP_SET_PSIZE(bp, x)     \
 206         BF64_SET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1, x)
 207
 208 #define BP_GET_COMPRESS(bp)             BF64_GET((bp)->blk_prop, 32, 7)
 209 #define BP_SET_COMPRESS(bp, x)          BF64_SET((bp)->blk_prop, 32, 7, x)
 210
 211 #define BP_GET_CHECKSUM(bp)             BF64_GET((bp)->blk_prop, 40, 8)
 212 #define BP_SET_CHECKSUM(bp, x)          BF64_SET((bp)->blk_prop, 40, 8, x)
 213
 214 #define BP_GET_TYPE(bp)                 BF64_GET((bp)->blk_prop, 48, 8)
 215 #define BP_SET_TYPE(bp, x)              BF64_SET((bp)->blk_prop, 48, 8, x)
 216
 217 #define BP_GET_LEVEL(bp)                BF64_GET((bp)->blk_prop, 56, 5)
 218 #define BP_SET_LEVEL(bp, x)             BF64_SET((bp)->blk_prop, 56, 5, x)
 219
 220 #define BP_IS_EMBEDDED(bp)              BF64_GET((bp)->blk_prop, 39, 1)
 221
 222 #define BP_GET_DEDUP(bp)                BF64_GET((bp)->blk_prop, 62, 1)
 223 #define BP_SET_DEDUP(bp, x)             BF64_SET((bp)->blk_prop, 62, 1, x)
 224
 225 #define BP_GET_BYTEORDER(bp)            BF64_GET((bp)->blk_prop, 63, 1)
 226 #define BP_SET_BYTEORDER(bp, x)         BF64_SET((bp)->blk_prop, 63, 1, x)
 227
 228 #define BP_PHYSICAL_BIRTH(bp)           \
 229         ((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)
 230
 231 #define BP_SET_BIRTH(bp, logical, physical)     \
 232 {                                               \
 233         (bp)->blk_birth = (logical);            \
 234         (bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \
 235 }
 236
 237 #define BP_GET_ASIZE(bp)        \
 238         (DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
 239                 DVA_GET_ASIZE(&(bp)->blk_dva[2]))
 240
 241 #define BP_GET_UCSIZE(bp) \
 242         ((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
 243         BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp));
 244
 245 #define BP_GET_NDVAS(bp)        \
 246         (!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
 247         !!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
 248         !!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
 249
 250 #define DVA_EQUAL(dva1, dva2)   \
 251         ((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
 252         (dva1)->dva_word[0] == (dva2)->dva_word[0])
 253
 254 #define BP_EQUAL(bp1, bp2)      \
 255         (BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) &&    \
 256         DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) &&    \
 257         DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) &&    \
 258         DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2]))
 259
 260 #define ZIO_CHECKSUM_EQUAL(zc1, zc2) \
 261         (0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
 262         ((zc1).zc_word[1] - (zc2).zc_word[1]) | \
 263         ((zc1).zc_word[2] - (zc2).zc_word[2]) | \
 264         ((zc1).zc_word[3] - (zc2).zc_word[3])))
 265
 266 #define DVA_IS_VALID(dva)       (DVA_GET_ASIZE(dva) != 0)
 267
 268 #define ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3)   \
 269 {                                               \
 270         (zcp)->zc_word[0] = w0;                 \
 271         (zcp)->zc_word[1] = w1;                 \
 272         (zcp)->zc_word[2] = w2;                 \
 273         (zcp)->zc_word[3] = w3;                 \
 274 }
 275
 276 #define BP_IDENTITY(bp)         (&(bp)->blk_dva[0])
 277 #define BP_IS_GANG(bp)          DVA_GET_GANG(BP_IDENTITY(bp))
 278 #define DVA_IS_EMPTY(dva)       ((dva)->dva_word[0] == 0ULL &&  \
 279                                 (dva)->dva_word[1] == 0ULL)
 280 #define BP_IS_HOLE(bp)          DVA_IS_EMPTY(BP_IDENTITY(bp))
 281
 282 /* BP_IS_RAIDZ(bp) assumes no block compression */
 283 #define BP_IS_RAIDZ(bp)         (DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \
 284                                 BP_GET_PSIZE(bp))
 285
 286 #define BP_ZERO(bp)                             \
 287 {                                               \
 288         (bp)->blk_dva[0].dva_word[0] = 0;       \
 289         (bp)->blk_dva[0].dva_word[1] = 0;       \
 290         (bp)->blk_dva[1].dva_word[0] = 0;       \
 291         (bp)->blk_dva[1].dva_word[1] = 0;       \
 292         (bp)->blk_dva[2].dva_word[0] = 0;       \
 293         (bp)->blk_dva[2].dva_word[1] = 0;       \
 294         (bp)->blk_prop = 0;                     \
 295         (bp)->blk_pad[0] = 0;                   \
 296         (bp)->blk_pad[1] = 0;                   \
 297         (bp)->blk_phys_birth = 0;               \
 298         (bp)->blk_birth = 0;                    \
 299         (bp)->blk_fill = 0;                     \
 300         ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0); \
 301 }
 302
 303 #define BPE_GET_ETYPE(bp)       BP_GET_CHECKSUM(bp)
 304 #define BPE_GET_LSIZE(bp)       \
 305         BF64_GET_SB((bp)->blk_prop, 0, 25, 0, 1)
 306 #define BPE_GET_PSIZE(bp)       \
 307         BF64_GET_SB((bp)->blk_prop, 25, 7, 0, 1)
 308
 309 typedef enum bp_embedded_type {
 310         BP_EMBEDDED_TYPE_DATA,
 311         NUM_BP_EMBEDDED_TYPES
 312 } bp_embedded_type_t;
 313
 314 #define BPE_NUM_WORDS 14
 315 #define BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
 316 #define BPE_IS_PAYLOADWORD(bp, wp) \
 317         ((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)
 318
 319 #ifdef _BIG_ENDIAN
 320 #define ZFS_HOST_BYTEORDER      (0ULL)
 321 #else
 322 #define ZFS_HOST_BYTEORDER      (1ULL)
 323 #endif
 324
 325 #define BP_SHOULD_BYTESWAP(bp)  (BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER)
 326
 327 #define BP_SPRINTF_LEN  320
 328
 329 #endif  /* _SYS_SPA_H */