usr/src/boot/sys/cddl/boot/zfs/zfsimpl.h

   1 /*-
   2  * Copyright (c) 2002 McAfee, Inc.
   3  * All rights reserved.
   4  *
   5  * This software was developed for the FreeBSD Project by Marshall
   6  * Kirk McKusick and McAfee Research,, the Security Research Division of
   7  * McAfee, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as
   8  * part of the DARPA CHATS research program
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31 /*
  32  * CDDL HEADER START
  33  *
  34  * The contents of this file are subject to the terms of the
  35  * Common Development and Distribution License (the "License").
  36  * You may not use this file except in compliance with the License.
  37  *
  38  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  39  * or http://www.opensolaris.org/os/licensing.
  40  * See the License for the specific language governing permissions
  41  * and limitations under the License.
  42  *
  43  * When distributing Covered Code, include this CDDL HEADER in each
  44  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  45  * If applicable, add the following below this CDDL HEADER, with the
  46  * fields enclosed by brackets "[]" replaced with your own identifying
  47  * information: Portions Copyright [yyyy] [name of copyright owner]
  48  *
  49  * CDDL HEADER END
  50  */
  51 /*
  52  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  53  * Use is subject to license terms.
  54  */
  55 /*
  56  * Copyright 2013 by Saso Kiselkov. All rights reserved.
  57  */
  58 /*
  59  * Copyright (c) 2013 by Delphix. All rights reserved.
  60  */
  61
  62 #define MAXNAMELEN      256
  63
  64 #define _NOTE(s)
  65
  66 typedef enum { B_FALSE, B_TRUE } boolean_t;
  67
  68 /* CRC64 table */
  69 #define ZFS_CRC64_POLY  0xC96C5795D7870F42ULL   /* ECMA-182, reflected form */
  70
  71 /*
  72  * Macros for various sorts of alignment and rounding when the alignment
  73  * is known to be a power of 2.
  74  */
  75 #define P2ALIGN(x, align)               ((x) & -(align))
  76 #define P2PHASE(x, align)               ((x) & ((align) - 1))
  77 #define P2NPHASE(x, align)              (-(x) & ((align) - 1))
  78 #define P2ROUNDUP(x, align)             (-(-(x) & -(align)))
  79 #define P2END(x, align)                 (-(~(x) & -(align)))
  80 #define P2PHASEUP(x, align, phase)      ((phase) - (((phase) - (x)) & -(align)))
  81 #define P2BOUNDARY(off, len, align)     (((off) ^ ((off) + (len) - 1)) > (align) - 1)
  82
  83 /*
  84  * General-purpose 32-bit and 64-bit bitfield encodings.
  85  */
  86 #define BF32_DECODE(x, low, len)        P2PHASE((x) >> (low), 1U << (len))
  87 #define BF64_DECODE(x, low, len)        P2PHASE((x) >> (low), 1ULL << (len))
  88 #define BF32_ENCODE(x, low, len)        (P2PHASE((x), 1U << (len)) << (low))
  89 #define BF64_ENCODE(x, low, len)        (P2PHASE((x), 1ULL << (len)) << (low))
  90
  91 #define BF32_GET(x, low, len)           BF32_DECODE(x, low, len)
  92 #define BF64_GET(x, low, len)           BF64_DECODE(x, low, len)
  93
  94 #define BF32_SET(x, low, len, val)      \
  95         ((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len))
  96 #define BF64_SET(x, low, len, val)      \
  97         ((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len))
  98
  99 #define BF32_GET_SB(x, low, len, shift, bias)   \
 100         ((BF32_GET(x, low, len) + (bias)) << (shift))
 101 #define BF64_GET_SB(x, low, len, shift, bias)   \
 102         ((BF64_GET(x, low, len) + (bias)) << (shift))
 103
 104 #define BF32_SET_SB(x, low, len, shift, bias, val)      \
 105         BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
 106 #define BF64_SET_SB(x, low, len, shift, bias, val)      \
 107         BF64_SET(x, low, len, ((val) >> (shift)) - (bias))
 108
 109 /*
 110  * Macros to reverse byte order
 111  */
 112 #define BSWAP_8(x)      ((x) & 0xff)
 113 #define BSWAP_16(x)     ((BSWAP_8(x) << 8) | BSWAP_8((x) >> 8))
 114 #define BSWAP_32(x)     ((BSWAP_16(x) << 16) | BSWAP_16((x) >> 16))
 115 #define BSWAP_64(x)     ((BSWAP_32(x) << 32) | BSWAP_32((x) >> 32))
 116
 117 #define SPA_MINBLOCKSHIFT       9
 118 #define SPA_OLDMAXBLOCKSHIFT    17
 119 #define SPA_MAXBLOCKSHIFT       24
 120 #define SPA_MINBLOCKSIZE        (1ULL << SPA_MINBLOCKSHIFT)
 121 #define SPA_OLDMAXBLOCKSIZE     (1ULL << SPA_OLDMAXBLOCKSHIFT)
 122 #define SPA_MAXBLOCKSIZE        (1ULL << SPA_MAXBLOCKSHIFT)
 123
 124 /*
 125  * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
 126  * The ASIZE encoding should be at least 64 times larger (6 more bits)
 127  * to support up to 4-way RAID-Z mirror mode with worst-case gang block
 128  * overhead, three DVAs per bp, plus one more bit in case we do anything
 129  * else that expands the ASIZE.
 130  */
 131 #define SPA_LSIZEBITS           16      /* LSIZE up to 32M (2^16 * 512) */
 132 #define SPA_PSIZEBITS           16      /* PSIZE up to 32M (2^16 * 512) */
 133 #define SPA_ASIZEBITS           24      /* ASIZE up to 64 times larger  */
 134
 135 /*
 136  * All SPA data is represented by 128-bit data virtual addresses (DVAs).
 137  * The members of the dva_t should be considered opaque outside the SPA.
 138  */
 139 typedef struct dva {
 140         uint64_t        dva_word[2];
 141 } dva_t;
 142
 143 /*
 144  * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
 145  */
 146 typedef struct zio_cksum {
 147         uint64_t        zc_word[4];
 148 } zio_cksum_t;
 149
 150 /*
 151  * Some checksums/hashes need a 256-bit initialization salt. This salt is kept
 152  * secret and is suitable for use in MAC algorithms as the key.
 153  */
 154 typedef struct zio_cksum_salt {
 155         uint8_t         zcs_bytes[32];
 156 } zio_cksum_salt_t;
 157
 158 /*
 159  * Each block is described by its DVAs, time of birth, checksum, etc.
 160  * The word-by-word, bit-by-bit layout of the blkptr is as follows:
 161  *
 162  *      64      56      48      40      32      24      16      8       0
 163  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 164  * 0    |               vdev1           | GRID  |         ASIZE         |
 165  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 166  * 1    |G|                      offset1                                |
 167  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 168  * 2    |               vdev2           | GRID  |         ASIZE         |
 169  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 170  * 3    |G|                      offset2                                |
 171  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 172  * 4    |               vdev3           | GRID  |         ASIZE         |
 173  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 174  * 5    |G|                      offset3                                |
 175  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 176  * 6    |BDX|lvl| type  | cksum |E| comp|    PSIZE      |     LSIZE     |
 177  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 178  * 7    |                       padding                                 |
 179  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 180  * 8    |                       padding                                 |
 181  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 182  * 9    |                       physical birth txg                      |
 183  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 184  * a    |                       logical birth txg                       |
 185  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 186  * b    |                       fill count                              |
 187  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 188  * c    |                       checksum[0]                             |
 189  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 190  * d    |                       checksum[1]                             |
 191  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 192  * e    |                       checksum[2]                             |
 193  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 194  * f    |                       checksum[3]                             |
 195  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 196  *
 197  * Legend:
 198  *
 199  * vdev         virtual device ID
 200  * offset       offset into virtual device
 201  * LSIZE        logical size
 202  * PSIZE        physical size (after compression)
 203  * ASIZE        allocated size (including RAID-Z parity and gang block headers)
 204  * GRID         RAID-Z layout information (reserved for future use)
 205  * cksum        checksum function
 206  * comp         compression function
 207  * G            gang block indicator
 208  * B            byteorder (endianness)
 209  * D            dedup
 210  * X            encryption (on version 30, which is not supported)
 211  * E            blkptr_t contains embedded data (see below)
 212  * lvl          level of indirection
 213  * type         DMU object type
 214  * phys birth   txg of block allocation; zero if same as logical birth txg
 215  * log. birth   transaction group in which the block was logically born
 216  * fill count   number of non-zero blocks under this bp
 217  * checksum[4]  256-bit checksum of the data this bp describes
 218  */
 219
 220 /*
 221  * "Embedded" blkptr_t's don't actually point to a block, instead they
 222  * have a data payload embedded in the blkptr_t itself.  See the comment
 223  * in blkptr.c for more details.
 224  *
 225  * The blkptr_t is laid out as follows:
 226  *
 227  *      64      56      48      40      32      24      16      8       0
 228  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 229  * 0    |      payload                                                  |
 230  * 1    |      payload                                                  |
 231  * 2    |      payload                                                  |
 232  * 3    |      payload                                                  |
 233  * 4    |      payload                                                  |
 234  * 5    |      payload                                                  |
 235  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 236  * 6    |BDX|lvl| type  | etype |E| comp| PSIZE|              LSIZE     |
 237  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 238  * 7    |      payload                                                  |
 239  * 8    |      payload                                                  |
 240  * 9    |      payload                                                  |
 241  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 242  * a    |                       logical birth txg                       |
 243  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 244  * b    |      payload                                                  |
 245  * c    |      payload                                                  |
 246  * d    |      payload                                                  |
 247  * e    |      payload                                                  |
 248  * f    |      payload                                                  |
 249  *      +-------+-------+-------+-------+-------+-------+-------+-------+
 250  *
 251  * Legend:
 252  *
 253  * payload              contains the embedded data
 254  * B (byteorder)        byteorder (endianness)
 255  * D (dedup)            padding (set to zero)
 256  * X                    encryption (set to zero; see above)
 257  * E (embedded)         set to one
 258  * lvl                  indirection level
 259  * type                 DMU object type
 260  * etype                how to interpret embedded data (BP_EMBEDDED_TYPE_*)
 261  * comp                 compression function of payload
 262  * PSIZE                size of payload after compression, in bytes
 263  * LSIZE                logical size of payload, in bytes
 264  *                      note that 25 bits is enough to store the largest
 265  *                      "normal" BP's LSIZE (2^16 * 2^9) in bytes
 266  * log. birth           transaction group in which the block was logically born
 267  *
 268  * Note that LSIZE and PSIZE are stored in bytes, whereas for non-embedded
 269  * bp's they are stored in units of SPA_MINBLOCKSHIFT.
 270  * Generally, the generic BP_GET_*() macros can be used on embedded BP's.
 271  * The B, D, X, lvl, type, and comp fields are stored the same as with normal
 272  * BP's so the BP_SET_* macros can be used with them.  etype, PSIZE, LSIZE must
 273  * be set with the BPE_SET_* macros.  BP_SET_EMBEDDED() should be called before
 274  * other macros, as they assert that they are only used on BP's of the correct
 275  * "embedded-ness".
 276  */
 277
 278 #define BPE_GET_ETYPE(bp)       \
 279         (ASSERT(BP_IS_EMBEDDED(bp)), \
 280         BF64_GET((bp)->blk_prop, 40, 8))
 281 #define BPE_SET_ETYPE(bp, t)    do { \
 282         ASSERT(BP_IS_EMBEDDED(bp)); \
 283         BF64_SET((bp)->blk_prop, 40, 8, t); \
 284 _NOTE(CONSTCOND) } while (0)
 285
 286 #define BPE_GET_LSIZE(bp)       \
 287         (ASSERT(BP_IS_EMBEDDED(bp)), \
 288         BF64_GET_SB((bp)->blk_prop, 0, 25, 0, 1))
 289 #define BPE_SET_LSIZE(bp, x)    do { \
 290         ASSERT(BP_IS_EMBEDDED(bp)); \
 291         BF64_SET_SB((bp)->blk_prop, 0, 25, 0, 1, x); \
 292 _NOTE(CONSTCOND) } while (0)
 293
 294 #define BPE_GET_PSIZE(bp)       \
 295         (ASSERT(BP_IS_EMBEDDED(bp)), \
 296         BF64_GET_SB((bp)->blk_prop, 25, 7, 0, 1))
 297 #define BPE_SET_PSIZE(bp, x)    do { \
 298         ASSERT(BP_IS_EMBEDDED(bp)); \
 299         BF64_SET_SB((bp)->blk_prop, 25, 7, 0, 1, x); \
 300 _NOTE(CONSTCOND) } while (0)
 301
 302 typedef enum bp_embedded_type {
 303         BP_EMBEDDED_TYPE_DATA,
 304         BP_EMBEDDED_TYPE_RESERVED, /* Reserved for an unintegrated feature. */
 305         NUM_BP_EMBEDDED_TYPES = BP_EMBEDDED_TYPE_RESERVED
 306 } bp_embedded_type_t;
 307
 308 #define BPE_NUM_WORDS 14
 309 #define BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
 310 #define BPE_IS_PAYLOADWORD(bp, wp) \
 311         ((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)
 312
 313 #define SPA_BLKPTRSHIFT 7               /* blkptr_t is 128 bytes        */
 314 #define SPA_DVAS_PER_BP 3               /* Number of DVAs in a bp       */
 315
 316 typedef struct blkptr {
 317         dva_t           blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
 318         uint64_t        blk_prop;       /* size, compression, type, etc     */
 319         uint64_t        blk_pad[2];     /* Extra space for the future       */
 320         uint64_t        blk_phys_birth; /* txg when block was allocated     */
 321         uint64_t        blk_birth;      /* transaction group at birth       */
 322         uint64_t        blk_fill;       /* fill count                       */
 323         zio_cksum_t     blk_cksum;      /* 256-bit checksum                 */
 324 } blkptr_t;
 325
 326 /*
 327  * Macros to get and set fields in a bp or DVA.
 328  */
 329 #define DVA_GET_ASIZE(dva)      \
 330         BF64_GET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, SPA_MINBLOCKSHIFT, 0)
 331 #define DVA_SET_ASIZE(dva, x)   \
 332         BF64_SET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, \
 333         SPA_MINBLOCKSHIFT, 0, x)
 334
 335 #define DVA_GET_GRID(dva)       BF64_GET((dva)->dva_word[0], 24, 8)
 336 #define DVA_SET_GRID(dva, x)    BF64_SET((dva)->dva_word[0], 24, 8, x)
 337
 338 #define DVA_GET_VDEV(dva)       BF64_GET((dva)->dva_word[0], 32, 32)
 339 #define DVA_SET_VDEV(dva, x)    BF64_SET((dva)->dva_word[0], 32, 32, x)
 340
 341 #define DVA_GET_OFFSET(dva)     \
 342         BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
 343 #define DVA_SET_OFFSET(dva, x)  \
 344         BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)
 345
 346 #define DVA_GET_GANG(dva)       BF64_GET((dva)->dva_word[1], 63, 1)
 347 #define DVA_SET_GANG(dva, x)    BF64_SET((dva)->dva_word[1], 63, 1, x)
 348
 349 #define BP_GET_LSIZE(bp)        \
 350         (BP_IS_EMBEDDED(bp) ?   \
 351         (BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA ? BPE_GET_LSIZE(bp) : 0): \
 352         BF64_GET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1))
 353 #define BP_SET_LSIZE(bp, x)     do { \
 354         ASSERT(!BP_IS_EMBEDDED(bp)); \
 355         BF64_SET_SB((bp)->blk_prop, \
 356             0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x); \
 357 _NOTE(CONSTCOND) } while (0)
 358
 359 #define BP_GET_PSIZE(bp)        \
 360         BF64_GET_SB((bp)->blk_prop, 16, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1)
 361 #define BP_SET_PSIZE(bp, x)     \
 362         BF64_SET_SB((bp)->blk_prop, 16, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x)
 363
 364 #define BP_GET_COMPRESS(bp)     BF64_GET((bp)->blk_prop, 32, 7)
 365 #define BP_SET_COMPRESS(bp, x)  BF64_SET((bp)->blk_prop, 32, 7, x)
 366
 367 #define BP_GET_CHECKSUM(bp)     BF64_GET((bp)->blk_prop, 40, 8)
 368 #define BP_SET_CHECKSUM(bp, x)  BF64_SET((bp)->blk_prop, 40, 8, x)
 369
 370 #define BP_GET_TYPE(bp)         BF64_GET((bp)->blk_prop, 48, 8)
 371 #define BP_SET_TYPE(bp, x)      BF64_SET((bp)->blk_prop, 48, 8, x)
 372
 373 #define BP_GET_LEVEL(bp)        BF64_GET((bp)->blk_prop, 56, 5)
 374 #define BP_SET_LEVEL(bp, x)     BF64_SET((bp)->blk_prop, 56, 5, x)
 375
 376 #define BP_IS_EMBEDDED(bp)      BF64_GET((bp)->blk_prop, 39, 1)
 377
 378 #define BP_GET_DEDUP(bp)        BF64_GET((bp)->blk_prop, 62, 1)
 379 #define BP_SET_DEDUP(bp, x)     BF64_SET((bp)->blk_prop, 62, 1, x)
 380
 381 #define BP_GET_BYTEORDER(bp)    BF64_GET((bp)->blk_prop, 63, 1)
 382 #define BP_SET_BYTEORDER(bp, x) BF64_SET((bp)->blk_prop, 63, 1, x)
 383
 384 #define BP_PHYSICAL_BIRTH(bp)           \
 385         ((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)
 386
 387 #define BP_GET_ASIZE(bp)        \
 388         (DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
 389                 DVA_GET_ASIZE(&(bp)->blk_dva[2]))
 390
 391 #define BP_GET_UCSIZE(bp) \
 392         ((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
 393         BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp));
 394
 395 #define BP_GET_NDVAS(bp)        \
 396         (!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
 397         !!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
 398         !!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
 399
 400 #define DVA_EQUAL(dva1, dva2)   \
 401         ((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
 402         (dva1)->dva_word[0] == (dva2)->dva_word[0])
 403
 404 #define ZIO_CHECKSUM_EQUAL(zc1, zc2) \
 405         (0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
 406         ((zc1).zc_word[1] - (zc2).zc_word[1]) | \
 407         ((zc1).zc_word[2] - (zc2).zc_word[2]) | \
 408         ((zc1).zc_word[3] - (zc2).zc_word[3])))
 409
 410
 411 #define DVA_IS_VALID(dva)       (DVA_GET_ASIZE(dva) != 0)
 412
 413 #define ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3)   \
 414 {                                               \
 415         (zcp)->zc_word[0] = w0;                 \
 416         (zcp)->zc_word[1] = w1;                 \
 417         (zcp)->zc_word[2] = w2;                 \
 418         (zcp)->zc_word[3] = w3;                 \
 419 }
 420
 421 #define BP_IDENTITY(bp)         (&(bp)->blk_dva[0])
 422 #define BP_IS_GANG(bp)          DVA_GET_GANG(BP_IDENTITY(bp))
 423 #define DVA_IS_EMPTY(dva)       ((dva)->dva_word[0] == 0ULL &&  \
 424         (dva)->dva_word[1] == 0ULL)
 425 #define BP_IS_HOLE(bp)          DVA_IS_EMPTY(BP_IDENTITY(bp))
 426 #define BP_IS_OLDER(bp, txg)    (!BP_IS_HOLE(bp) && (bp)->blk_birth < (txg))
 427
 428 #define BP_ZERO(bp)                             \
 429 {                                               \
 430         (bp)->blk_dva[0].dva_word[0] = 0;       \
 431         (bp)->blk_dva[0].dva_word[1] = 0;       \
 432         (bp)->blk_dva[1].dva_word[0] = 0;       \
 433         (bp)->blk_dva[1].dva_word[1] = 0;       \
 434         (bp)->blk_dva[2].dva_word[0] = 0;       \
 435         (bp)->blk_dva[2].dva_word[1] = 0;       \
 436         (bp)->blk_prop = 0;                     \
 437         (bp)->blk_pad[0] = 0;                   \
 438         (bp)->blk_pad[1] = 0;                   \
 439         (bp)->blk_phys_birth = 0;               \
 440         (bp)->blk_birth = 0;                    \
 441         (bp)->blk_fill = 0;                     \
 442         ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0); \
 443 }
 444
 445 #define BPE_NUM_WORDS 14
 446 #define BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
 447 #define BPE_IS_PAYLOADWORD(bp, wp) \
 448         ((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)
 449
 450 /*
 451  * Embedded checksum
 452  */
 453 #define ZEC_MAGIC       0x210da7ab10c7a11ULL
 454
 455 typedef struct zio_eck {
 456         uint64_t        zec_magic;      /* for validation, endianness   */
 457         zio_cksum_t     zec_cksum;      /* 256-bit checksum             */
 458 } zio_eck_t;
 459
 460 /*
 461  * Gang block headers are self-checksumming and contain an array
 462  * of block pointers.
 463  */
 464 #define SPA_GANGBLOCKSIZE       SPA_MINBLOCKSIZE
 465 #define SPA_GBH_NBLKPTRS        ((SPA_GANGBLOCKSIZE - \
 466         sizeof (zio_eck_t)) / sizeof (blkptr_t))
 467 #define SPA_GBH_FILLER          ((SPA_GANGBLOCKSIZE - \
 468         sizeof (zio_eck_t) - \
 469         (SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\
 470         sizeof (uint64_t))
 471
 472 typedef struct zio_gbh {
 473         blkptr_t                zg_blkptr[SPA_GBH_NBLKPTRS];
 474         uint64_t                zg_filler[SPA_GBH_FILLER];
 475         zio_eck_t               zg_tail;
 476 } zio_gbh_phys_t;
 477
 478 #define VDEV_RAIDZ_MAXPARITY    3
 479
 480 #define VDEV_PAD_SIZE           (8 << 10)
 481 /* 2 padding areas (vl_pad1 and vl_pad2) to skip */
 482 #define VDEV_SKIP_SIZE          VDEV_PAD_SIZE * 2
 483 #define VDEV_PHYS_SIZE          (112 << 10)
 484 #define VDEV_UBERBLOCK_RING     (128 << 10)
 485
 486 #define VDEV_UBERBLOCK_SHIFT(vd)        \
 487         MAX((vd)->v_top->v_ashift, UBERBLOCK_SHIFT)
 488 #define VDEV_UBERBLOCK_COUNT(vd)        \
 489         (VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(vd))
 490 #define VDEV_UBERBLOCK_OFFSET(vd, n)    \
 491         offsetof(vdev_label_t, vl_uberblock[(n) << VDEV_UBERBLOCK_SHIFT(vd)])
 492 #define VDEV_UBERBLOCK_SIZE(vd)         (1ULL << VDEV_UBERBLOCK_SHIFT(vd))
 493
 494 typedef struct vdev_phys {
 495         char            vp_nvlist[VDEV_PHYS_SIZE - sizeof (zio_eck_t)];
 496         zio_eck_t       vp_zbt;
 497 } vdev_phys_t;
 498
 499 typedef struct vdev_label {
 500         char            vl_pad1[VDEV_PAD_SIZE];                 /*  8K  */
 501         char            vl_pad2[VDEV_PAD_SIZE];                 /*  8K  */
 502         vdev_phys_t     vl_vdev_phys;                           /* 112K */
 503         char            vl_uberblock[VDEV_UBERBLOCK_RING];      /* 128K */
 504 } vdev_label_t;                                                 /* 256K total */
 505
 506 /*
 507  * vdev_dirty() flags
 508  */
 509 #define VDD_METASLAB    0x01
 510 #define VDD_DTL         0x02
 511
 512 /*
 513  * Size and offset of embedded boot loader region on each label.
 514  * The total size of the first two labels plus the boot area is 4MB.
 515  */
 516 #define VDEV_BOOT_OFFSET        (2 * sizeof (vdev_label_t))
 517 #define VDEV_BOOT_SIZE          (7ULL << 19)                    /* 3.5M */
 518
 519 /*
 520  * Size of label regions at the start and end of each leaf device.
 521  */
 522 #define VDEV_LABEL_START_SIZE   (2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
 523 #define VDEV_LABEL_END_SIZE     (2 * sizeof (vdev_label_t))
 524 #define VDEV_LABELS             4
 525
 526 enum zio_checksum {
 527         ZIO_CHECKSUM_INHERIT = 0,
 528         ZIO_CHECKSUM_ON,
 529         ZIO_CHECKSUM_OFF,
 530         ZIO_CHECKSUM_LABEL,
 531         ZIO_CHECKSUM_GANG_HEADER,
 532         ZIO_CHECKSUM_ZILOG,
 533         ZIO_CHECKSUM_FLETCHER_2,
 534         ZIO_CHECKSUM_FLETCHER_4,
 535         ZIO_CHECKSUM_SHA256,
 536         ZIO_CHECKSUM_ZILOG2,
 537         ZIO_CHECKSUM_NOPARITY,
 538         ZIO_CHECKSUM_SHA512,
 539         ZIO_CHECKSUM_SKEIN,
 540         ZIO_CHECKSUM_EDONR,
 541         ZIO_CHECKSUM_FUNCTIONS
 542 };
 543
 544 #define ZIO_CHECKSUM_ON_VALUE   ZIO_CHECKSUM_FLETCHER_4
 545 #define ZIO_CHECKSUM_DEFAULT    ZIO_CHECKSUM_ON
 546
 547 enum zio_compress {
 548         ZIO_COMPRESS_INHERIT = 0,
 549         ZIO_COMPRESS_ON,
 550         ZIO_COMPRESS_OFF,
 551         ZIO_COMPRESS_LZJB,
 552         ZIO_COMPRESS_EMPTY,
 553         ZIO_COMPRESS_GZIP_1,
 554         ZIO_COMPRESS_GZIP_2,
 555         ZIO_COMPRESS_GZIP_3,
 556         ZIO_COMPRESS_GZIP_4,
 557         ZIO_COMPRESS_GZIP_5,
 558         ZIO_COMPRESS_GZIP_6,
 559         ZIO_COMPRESS_GZIP_7,
 560         ZIO_COMPRESS_GZIP_8,
 561         ZIO_COMPRESS_GZIP_9,
 562         ZIO_COMPRESS_ZLE,
 563         ZIO_COMPRESS_LZ4,
 564         ZIO_COMPRESS_FUNCTIONS
 565 };
 566
 567 #define ZIO_COMPRESS_ON_VALUE   ZIO_COMPRESS_LZJB
 568 #define ZIO_COMPRESS_DEFAULT    ZIO_COMPRESS_OFF
 569
 570 /* nvlist pack encoding */
 571 #define NV_ENCODE_NATIVE        0
 572 #define NV_ENCODE_XDR           1
 573
 574 typedef enum {
 575         DATA_TYPE_UNKNOWN = 0,
 576         DATA_TYPE_BOOLEAN,
 577         DATA_TYPE_BYTE,
 578         DATA_TYPE_INT16,
 579         DATA_TYPE_UINT16,
 580         DATA_TYPE_INT32,
 581         DATA_TYPE_UINT32,
 582         DATA_TYPE_INT64,
 583         DATA_TYPE_UINT64,
 584         DATA_TYPE_STRING,
 585         DATA_TYPE_BYTE_ARRAY,
 586         DATA_TYPE_INT16_ARRAY,
 587         DATA_TYPE_UINT16_ARRAY,
 588         DATA_TYPE_INT32_ARRAY,
 589         DATA_TYPE_UINT32_ARRAY,
 590         DATA_TYPE_INT64_ARRAY,
 591         DATA_TYPE_UINT64_ARRAY,
 592         DATA_TYPE_STRING_ARRAY,
 593         DATA_TYPE_HRTIME,
 594         DATA_TYPE_NVLIST,
 595         DATA_TYPE_NVLIST_ARRAY,
 596         DATA_TYPE_BOOLEAN_VALUE,
 597         DATA_TYPE_INT8,
 598         DATA_TYPE_UINT8,
 599         DATA_TYPE_BOOLEAN_ARRAY,
 600         DATA_TYPE_INT8_ARRAY,
 601         DATA_TYPE_UINT8_ARRAY
 602 } data_type_t;
 603
 604 /*
 605  * On-disk version number.
 606  */
 607 #define SPA_VERSION_1                   1ULL
 608 #define SPA_VERSION_2                   2ULL
 609 #define SPA_VERSION_3                   3ULL
 610 #define SPA_VERSION_4                   4ULL
 611 #define SPA_VERSION_5                   5ULL
 612 #define SPA_VERSION_6                   6ULL
 613 #define SPA_VERSION_7                   7ULL
 614 #define SPA_VERSION_8                   8ULL
 615 #define SPA_VERSION_9                   9ULL
 616 #define SPA_VERSION_10                  10ULL
 617 #define SPA_VERSION_11                  11ULL
 618 #define SPA_VERSION_12                  12ULL
 619 #define SPA_VERSION_13                  13ULL
 620 #define SPA_VERSION_14                  14ULL
 621 #define SPA_VERSION_15                  15ULL
 622 #define SPA_VERSION_16                  16ULL
 623 #define SPA_VERSION_17                  17ULL
 624 #define SPA_VERSION_18                  18ULL
 625 #define SPA_VERSION_19                  19ULL
 626 #define SPA_VERSION_20                  20ULL
 627 #define SPA_VERSION_21                  21ULL
 628 #define SPA_VERSION_22                  22ULL
 629 #define SPA_VERSION_23                  23ULL
 630 #define SPA_VERSION_24                  24ULL
 631 #define SPA_VERSION_25                  25ULL
 632 #define SPA_VERSION_26                  26ULL
 633 #define SPA_VERSION_27                  27ULL
 634 #define SPA_VERSION_28                  28ULL
 635 #define SPA_VERSION_5000                5000ULL
 636
 637 /*
 638  * When bumping up SPA_VERSION, make sure GRUB ZFS understands the on-disk
 639  * format change. Go to usr/src/grub/grub-0.97/stage2/{zfs-include/, fsys_zfs*},
 640  * and do the appropriate changes.  Also bump the version number in
 641  * usr/src/grub/capability.
 642  */
 643 #define SPA_VERSION                     SPA_VERSION_5000
 644 #define SPA_VERSION_STRING              "5000"
 645
 646 /*
 647  * Symbolic names for the changes that caused a SPA_VERSION switch.
 648  * Used in the code when checking for presence or absence of a feature.
 649  * Feel free to define multiple symbolic names for each version if there
 650  * were multiple changes to on-disk structures during that version.
 651  *
 652  * NOTE: When checking the current SPA_VERSION in your code, be sure
 653  *       to use spa_version() since it reports the version of the
 654  *       last synced uberblock.  Checking the in-flight version can
 655  *       be dangerous in some cases.
 656  */
 657 #define SPA_VERSION_INITIAL             SPA_VERSION_1
 658 #define SPA_VERSION_DITTO_BLOCKS        SPA_VERSION_2
 659 #define SPA_VERSION_SPARES              SPA_VERSION_3
 660 #define SPA_VERSION_RAID6               SPA_VERSION_3
 661 #define SPA_VERSION_BPLIST_ACCOUNT      SPA_VERSION_3
 662 #define SPA_VERSION_RAIDZ_DEFLATE       SPA_VERSION_3
 663 #define SPA_VERSION_DNODE_BYTES         SPA_VERSION_3
 664 #define SPA_VERSION_ZPOOL_HISTORY       SPA_VERSION_4
 665 #define SPA_VERSION_GZIP_COMPRESSION    SPA_VERSION_5
 666 #define SPA_VERSION_BOOTFS              SPA_VERSION_6
 667 #define SPA_VERSION_SLOGS               SPA_VERSION_7
 668 #define SPA_VERSION_DELEGATED_PERMS     SPA_VERSION_8
 669 #define SPA_VERSION_FUID                SPA_VERSION_9
 670 #define SPA_VERSION_REFRESERVATION      SPA_VERSION_9
 671 #define SPA_VERSION_REFQUOTA            SPA_VERSION_9
 672 #define SPA_VERSION_UNIQUE_ACCURATE     SPA_VERSION_9
 673 #define SPA_VERSION_L2CACHE             SPA_VERSION_10
 674 #define SPA_VERSION_NEXT_CLONES         SPA_VERSION_11
 675 #define SPA_VERSION_ORIGIN              SPA_VERSION_11
 676 #define SPA_VERSION_DSL_SCRUB           SPA_VERSION_11
 677 #define SPA_VERSION_SNAP_PROPS          SPA_VERSION_12
 678 #define SPA_VERSION_USED_BREAKDOWN      SPA_VERSION_13
 679 #define SPA_VERSION_PASSTHROUGH_X       SPA_VERSION_14
 680 #define SPA_VERSION_USERSPACE           SPA_VERSION_15
 681 #define SPA_VERSION_STMF_PROP           SPA_VERSION_16
 682 #define SPA_VERSION_RAIDZ3              SPA_VERSION_17
 683 #define SPA_VERSION_USERREFS            SPA_VERSION_18
 684 #define SPA_VERSION_HOLES               SPA_VERSION_19
 685 #define SPA_VERSION_ZLE_COMPRESSION     SPA_VERSION_20
 686 #define SPA_VERSION_DEDUP               SPA_VERSION_21
 687 #define SPA_VERSION_RECVD_PROPS         SPA_VERSION_22
 688 #define SPA_VERSION_SLIM_ZIL            SPA_VERSION_23
 689 #define SPA_VERSION_SA                  SPA_VERSION_24
 690 #define SPA_VERSION_SCAN                SPA_VERSION_25
 691 #define SPA_VERSION_DIR_CLONES          SPA_VERSION_26
 692 #define SPA_VERSION_DEADLISTS           SPA_VERSION_26
 693 #define SPA_VERSION_FAST_SNAP           SPA_VERSION_27
 694 #define SPA_VERSION_MULTI_REPLACE       SPA_VERSION_28
 695 #define SPA_VERSION_BEFORE_FEATURES     SPA_VERSION_28
 696 #define SPA_VERSION_FEATURES            SPA_VERSION_5000
 697
 698 #define SPA_VERSION_IS_SUPPORTED(v) \
 699         (((v) >= SPA_VERSION_INITIAL && (v) <= SPA_VERSION_BEFORE_FEATURES) || \
 700         ((v) >= SPA_VERSION_FEATURES && (v) <= SPA_VERSION))
 701
 702 /*
 703  * The following are configuration names used in the nvlist describing a pool's
 704  * configuration.
 705  */
 706 #define ZPOOL_CONFIG_VERSION            "version"
 707 #define ZPOOL_CONFIG_POOL_NAME          "name"
 708 #define ZPOOL_CONFIG_POOL_STATE         "state"
 709 #define ZPOOL_CONFIG_POOL_TXG           "txg"
 710 #define ZPOOL_CONFIG_POOL_GUID          "pool_guid"
 711 #define ZPOOL_CONFIG_CREATE_TXG         "create_txg"
 712 #define ZPOOL_CONFIG_TOP_GUID           "top_guid"
 713 #define ZPOOL_CONFIG_VDEV_TREE          "vdev_tree"
 714 #define ZPOOL_CONFIG_TYPE               "type"
 715 #define ZPOOL_CONFIG_CHILDREN           "children"
 716 #define ZPOOL_CONFIG_ID                 "id"
 717 #define ZPOOL_CONFIG_GUID               "guid"
 718 #define ZPOOL_CONFIG_PATH               "path"
 719 #define ZPOOL_CONFIG_DEVID              "devid"
 720 #define ZPOOL_CONFIG_PHYS_PATH          "phys_path"
 721 #define ZPOOL_CONFIG_METASLAB_ARRAY     "metaslab_array"
 722 #define ZPOOL_CONFIG_METASLAB_SHIFT     "metaslab_shift"
 723 #define ZPOOL_CONFIG_ASHIFT             "ashift"
 724 #define ZPOOL_CONFIG_ASIZE              "asize"
 725 #define ZPOOL_CONFIG_DTL                "DTL"
 726 #define ZPOOL_CONFIG_STATS              "stats"
 727 #define ZPOOL_CONFIG_WHOLE_DISK         "whole_disk"
 728 #define ZPOOL_CONFIG_ERRCOUNT           "error_count"
 729 #define ZPOOL_CONFIG_NOT_PRESENT        "not_present"
 730 #define ZPOOL_CONFIG_SPARES             "spares"
 731 #define ZPOOL_CONFIG_IS_SPARE           "is_spare"
 732 #define ZPOOL_CONFIG_NPARITY            "nparity"
 733 #define ZPOOL_CONFIG_HOSTID             "hostid"
 734 #define ZPOOL_CONFIG_HOSTNAME           "hostname"
 735 #define ZPOOL_CONFIG_IS_LOG             "is_log"
 736 #define ZPOOL_CONFIG_TIMESTAMP          "timestamp" /* not stored on disk */
 737 #define ZPOOL_CONFIG_FEATURES_FOR_READ  "features_for_read"
 738
 739 /*
 740  * The persistent vdev state is stored as separate values rather than a single
 741  * 'vdev_state' entry.  This is because a device can be in multiple states, such
 742  * as offline and degraded.
 743  */
 744 #define ZPOOL_CONFIG_OFFLINE            "offline"
 745 #define ZPOOL_CONFIG_FAULTED            "faulted"
 746 #define ZPOOL_CONFIG_DEGRADED           "degraded"
 747 #define ZPOOL_CONFIG_REMOVED            "removed"
 748 #define ZPOOL_CONFIG_FRU                "fru"
 749 #define ZPOOL_CONFIG_AUX_STATE          "aux_state"
 750
 751 #define VDEV_TYPE_ROOT                  "root"
 752 #define VDEV_TYPE_MIRROR                "mirror"
 753 #define VDEV_TYPE_REPLACING             "replacing"
 754 #define VDEV_TYPE_RAIDZ                 "raidz"
 755 #define VDEV_TYPE_DISK                  "disk"
 756 #define VDEV_TYPE_FILE                  "file"
 757 #define VDEV_TYPE_MISSING               "missing"
 758 #define VDEV_TYPE_HOLE                  "hole"
 759 #define VDEV_TYPE_SPARE                 "spare"
 760 #define VDEV_TYPE_LOG                   "log"
 761 #define VDEV_TYPE_L2CACHE               "l2cache"
 762
 763 /*
 764  * This is needed in userland to report the minimum necessary device size.
 765  */
 766 #define SPA_MINDEVSIZE          (64ULL << 20)
 767
 768 /*
 769  * The location of the pool configuration repository, shared between kernel and
 770  * userland.
 771  */
 772 #define ZPOOL_CACHE             "/boot/zfs/zpool.cache"
 773
 774 /*
 775  * vdev states are ordered from least to most healthy.
 776  * A vdev that's CANT_OPEN or below is considered unusable.
 777  */
 778 typedef enum vdev_state {
 779         VDEV_STATE_UNKNOWN = 0, /* Uninitialized vdev                   */
 780         VDEV_STATE_CLOSED,      /* Not currently open                   */
 781         VDEV_STATE_OFFLINE,     /* Not allowed to open                  */
 782         VDEV_STATE_REMOVED,     /* Explicitly removed from system       */
 783         VDEV_STATE_CANT_OPEN,   /* Tried to open, but failed            */
 784         VDEV_STATE_FAULTED,     /* External request to fault device     */
 785         VDEV_STATE_DEGRADED,    /* Replicated vdev with unhealthy kids  */
 786         VDEV_STATE_HEALTHY      /* Presumed good                        */
 787 } vdev_state_t;
 788
 789 /*
 790  * vdev aux states.  When a vdev is in the CANT_OPEN state, the aux field
 791  * of the vdev stats structure uses these constants to distinguish why.
 792  */
 793 typedef enum vdev_aux {
 794         VDEV_AUX_NONE,          /* no error                             */
 795         VDEV_AUX_OPEN_FAILED,   /* ldi_open_*() or vn_open() failed     */
 796         VDEV_AUX_CORRUPT_DATA,  /* bad label or disk contents           */
 797         VDEV_AUX_NO_REPLICAS,   /* insufficient number of replicas      */
 798         VDEV_AUX_BAD_GUID_SUM,  /* vdev guid sum doesn't match          */
 799         VDEV_AUX_TOO_SMALL,     /* vdev size is too small               */
 800         VDEV_AUX_BAD_LABEL,     /* the label is OK but invalid          */
 801         VDEV_AUX_VERSION_NEWER, /* on-disk version is too new           */
 802         VDEV_AUX_VERSION_OLDER, /* on-disk version is too old           */
 803         VDEV_AUX_SPARED         /* hot spare used in another pool       */
 804 } vdev_aux_t;
 805
 806 /*
 807  * pool state.  The following states are written to disk as part of the normal
 808  * SPA lifecycle: ACTIVE, EXPORTED, DESTROYED, SPARE.  The remaining states are
 809  * software abstractions used at various levels to communicate pool state.
 810  */
 811 typedef enum pool_state {
 812         POOL_STATE_ACTIVE = 0,          /* In active use                */
 813         POOL_STATE_EXPORTED,            /* Explicitly exported          */
 814         POOL_STATE_DESTROYED,           /* Explicitly destroyed         */
 815         POOL_STATE_SPARE,               /* Reserved for hot spare use   */
 816         POOL_STATE_UNINITIALIZED,       /* Internal spa_t state         */
 817         POOL_STATE_UNAVAIL,             /* Internal libzfs state        */
 818         POOL_STATE_POTENTIALLY_ACTIVE   /* Internal libzfs state        */
 819 } pool_state_t;
 820
 821 /*
 822  * The uberblock version is incremented whenever an incompatible on-disk
 823  * format change is made to the SPA, DMU, or ZAP.
 824  *
 825  * Note: the first two fields should never be moved.  When a storage pool
 826  * is opened, the uberblock must be read off the disk before the version
 827  * can be checked.  If the ub_version field is moved, we may not detect
 828  * version mismatch.  If the ub_magic field is moved, applications that
 829  * expect the magic number in the first word won't work.
 830  */
 831 #define UBERBLOCK_MAGIC         0x00bab10c              /* oo-ba-bloc!  */
 832 #define UBERBLOCK_SHIFT         10                      /* up to 1K     */
 833
 834 struct uberblock {
 835         uint64_t        ub_magic;       /* UBERBLOCK_MAGIC              */
 836         uint64_t        ub_version;     /* SPA_VERSION                  */
 837         uint64_t        ub_txg;         /* txg of last sync             */
 838         uint64_t        ub_guid_sum;    /* sum of all vdev guids        */
 839         uint64_t        ub_timestamp;   /* UTC time of last sync        */
 840         blkptr_t        ub_rootbp;      /* MOS objset_phys_t            */
 841 };
 842
 843 /*
 844  * Flags.
 845  */
 846 #define DNODE_MUST_BE_ALLOCATED 1
 847 #define DNODE_MUST_BE_FREE      2
 848
 849 /*
 850  * Fixed constants.
 851  */
 852 #define DNODE_SHIFT             9       /* 512 bytes */
 853 #define DN_MIN_INDBLKSHIFT      12      /* 4k */
 854 #define DN_MAX_INDBLKSHIFT      14      /* 16k */
 855 #define DNODE_BLOCK_SHIFT       14      /* 16k */
 856 #define DNODE_CORE_SIZE         64      /* 64 bytes for dnode sans blkptrs */
 857 #define DN_MAX_OBJECT_SHIFT     48      /* 256 trillion (zfs_fid_t limit) */
 858 #define DN_MAX_OFFSET_SHIFT     64      /* 2^64 bytes in a dnode */
 859
 860 /*
 861  * Derived constants.
 862  */
 863 #define DNODE_MIN_SIZE          (1 << DNODE_SHIFT)
 864 #define DNODE_MAX_SIZE          (1 << DNODE_BLOCK_SHIFT)
 865 #define DNODE_BLOCK_SIZE        (1 << DNODE_BLOCK_SHIFT)
 866 #define DNODE_MIN_SLOTS         (DNODE_MIN_SIZE >> DNODE_SHIFT)
 867 #define DNODE_MAX_SLOTS         (DNODE_MAX_SIZE >> DNODE_SHIFT)
 868 #define DN_BONUS_SIZE(dnsize)   ((dnsize) - DNODE_CORE_SIZE - \
 869         (1 << SPA_BLKPTRSHIFT))
 870 #define DN_SLOTS_TO_BONUSLEN(slots)     DN_BONUS_SIZE((slots) << DNODE_SHIFT)
 871 #define DN_OLD_MAX_BONUSLEN             (DN_BONUS_SIZE(DNODE_MIN_SIZE))
 872 #define DN_MAX_NBLKPTR          ((DNODE_MIN_SIZE - DNODE_CORE_SIZE) >> \
 873         SPA_BLKPTRSHIFT)
 874 #define DN_MAX_OBJECT           (1ULL << DN_MAX_OBJECT_SHIFT)
 875 #define DN_ZERO_BONUSLEN        (DN_BONUS_SIZE(DNODE_MAX_SIZE) + 1)
 876
 877 #define DNODES_PER_BLOCK_SHIFT  (DNODE_BLOCK_SHIFT - DNODE_SHIFT)
 878 #define DNODES_PER_BLOCK        (1ULL << DNODES_PER_BLOCK_SHIFT)
 879 #define DNODES_PER_LEVEL_SHIFT  (DN_MAX_INDBLKSHIFT - SPA_BLKPTRSHIFT)
 880
 881 /* The +2 here is a cheesy way to round up */
 882 #define DN_MAX_LEVELS   (2 + ((DN_MAX_OFFSET_SHIFT - SPA_MINBLOCKSHIFT) / \
 883         (DN_MIN_INDBLKSHIFT - SPA_BLKPTRSHIFT)))
 884
 885 #define DN_BONUS(dnp)   ((void*)((dnp)->dn_bonus + \
 886         (((dnp)->dn_nblkptr - 1) * sizeof (blkptr_t))))
 887
 888 #define DN_USED_BYTES(dnp) (((dnp)->dn_flags & DNODE_FLAG_USED_BYTES) ? \
 889         (dnp)->dn_used : (dnp)->dn_used << SPA_MINBLOCKSHIFT)
 890
 891 #define EPB(blkshift, typeshift)        (1 << (blkshift - typeshift))
 892
 893 /* Is dn_used in bytes?  if not, it's in multiples of SPA_MINBLOCKSIZE */
 894 #define DNODE_FLAG_USED_BYTES           (1<<0)
 895 #define DNODE_FLAG_USERUSED_ACCOUNTED   (1<<1)
 896
 897 /* Does dnode have a SA spill blkptr in bonus? */
 898 #define DNODE_FLAG_SPILL_BLKPTR (1<<2)
 899
 900 typedef struct dnode_phys {
 901         uint8_t dn_type;                /* dmu_object_type_t */
 902         uint8_t dn_indblkshift;         /* ln2(indirect block size) */
 903         uint8_t dn_nlevels;             /* 1=dn_blkptr->data blocks */
 904         uint8_t dn_nblkptr;             /* length of dn_blkptr */
 905         uint8_t dn_bonustype;           /* type of data in bonus buffer */
 906         uint8_t dn_checksum;            /* ZIO_CHECKSUM type */
 907         uint8_t dn_compress;            /* ZIO_COMPRESS type */
 908         uint8_t dn_flags;               /* DNODE_FLAG_* */
 909         uint16_t dn_datablkszsec;       /* data block size in 512b sectors */
 910         uint16_t dn_bonuslen;           /* length of dn_bonus */
 911         uint8_t dn_extra_slots;         /* # of subsequent slots consumed */
 912         uint8_t dn_pad2[3];
 913
 914         /* accounting is protected by dn_dirty_mtx */
 915         uint64_t dn_maxblkid;           /* largest allocated block ID */
 916         uint64_t dn_used;               /* bytes (or sectors) of disk space */
 917
 918         uint64_t dn_pad3[4];
 919
 920         /*
 921          * The tail region is 448 bytes for a 512 byte dnode, and
 922          * correspondingly larger for larger dnode sizes. The spill
 923          * block pointer, when present, is always at the end of the tail
 924          * region. There are three ways this space may be used, using
 925          * a 512 byte dnode for this diagram:
 926          *
 927          * 0       64      128     192     256     320     384     448 (offset)
 928          * +---------------+---------------+---------------+-------+
 929          * | dn_blkptr[0]  | dn_blkptr[1]  | dn_blkptr[2]  | /     |
 930          * +---------------+---------------+---------------+-------+
 931          * | dn_blkptr[0]  | dn_bonus[0..319]                      |
 932          * +---------------+-----------------------+---------------+
 933          * | dn_blkptr[0]  | dn_bonus[0..191]      | dn_spill      |
 934          * +---------------+-----------------------+---------------+
 935          */
 936         union {
 937                 blkptr_t dn_blkptr[1+DN_OLD_MAX_BONUSLEN/sizeof (blkptr_t)];
 938                 struct {
 939                         blkptr_t __dn_ignore1;
 940                         uint8_t dn_bonus[DN_OLD_MAX_BONUSLEN];
 941                 };
 942                 struct {
 943                         blkptr_t __dn_ignore2;
 944                         uint8_t __dn_ignore3[DN_OLD_MAX_BONUSLEN -
 945                             sizeof (blkptr_t)];
 946                         blkptr_t dn_spill;
 947                 };
 948         };
 949 } dnode_phys_t;
 950
 951 #define DN_SPILL_BLKPTR(dnp)    (blkptr_t *)((char *)(dnp) + \
 952         (((dnp)->dn_extra_slots + 1) << DNODE_SHIFT) - (1 << SPA_BLKPTRSHIFT))
 953
 954 typedef enum dmu_object_byteswap {
 955         DMU_BSWAP_UINT8,
 956         DMU_BSWAP_UINT16,
 957         DMU_BSWAP_UINT32,
 958         DMU_BSWAP_UINT64,
 959         DMU_BSWAP_ZAP,
 960         DMU_BSWAP_DNODE,
 961         DMU_BSWAP_OBJSET,
 962         DMU_BSWAP_ZNODE,
 963         DMU_BSWAP_OLDACL,
 964         DMU_BSWAP_ACL,
 965         /*
 966          * Allocating a new byteswap type number makes the on-disk format
 967          * incompatible with any other format that uses the same number.
 968          *
 969          * Data can usually be structured to work with one of the
 970          * DMU_BSWAP_UINT* or DMU_BSWAP_ZAP types.
 971          */
 972         DMU_BSWAP_NUMFUNCS
 973 } dmu_object_byteswap_t;
 974
 975 #define DMU_OT_NEWTYPE 0x80
 976 #define DMU_OT_METADATA 0x40
 977 #define DMU_OT_BYTESWAP_MASK 0x3f
 978
 979 /*
 980  * Defines a uint8_t object type. Object types specify if the data
 981  * in the object is metadata (boolean) and how to byteswap the data
 982  * (dmu_object_byteswap_t).
 983  */
 984 #define DMU_OT(byteswap, metadata) \
 985         (DMU_OT_NEWTYPE | \
 986         ((metadata) ? DMU_OT_METADATA : 0) | \
 987         ((byteswap) & DMU_OT_BYTESWAP_MASK))
 988
 989 typedef enum dmu_object_type {
 990         DMU_OT_NONE,
 991         /* general: */
 992         DMU_OT_OBJECT_DIRECTORY,        /* ZAP */
 993         DMU_OT_OBJECT_ARRAY,            /* UINT64 */
 994         DMU_OT_PACKED_NVLIST,           /* UINT8 (XDR by nvlist_pack/unpack) */
 995         DMU_OT_PACKED_NVLIST_SIZE,      /* UINT64 */
 996         DMU_OT_BPLIST,                  /* UINT64 */
 997         DMU_OT_BPLIST_HDR,              /* UINT64 */
 998         /* spa: */
 999         DMU_OT_SPACE_MAP_HEADER,        /* UINT64 */
1000         DMU_OT_SPACE_MAP,               /* UINT64 */
1001         /* zil: */
1002         DMU_OT_INTENT_LOG,              /* UINT64 */
1003         /* dmu: */
1004         DMU_OT_DNODE,                   /* DNODE */
1005         DMU_OT_OBJSET,                  /* OBJSET */
1006         /* dsl: */
1007         DMU_OT_DSL_DIR,                 /* UINT64 */
1008         DMU_OT_DSL_DIR_CHILD_MAP,       /* ZAP */
1009         DMU_OT_DSL_DS_SNAP_MAP,         /* ZAP */
1010         DMU_OT_DSL_PROPS,               /* ZAP */
1011         DMU_OT_DSL_DATASET,             /* UINT64 */
1012         /* zpl: */
1013         DMU_OT_ZNODE,                   /* ZNODE */
1014         DMU_OT_OLDACL,                  /* Old ACL */
1015         DMU_OT_PLAIN_FILE_CONTENTS,     /* UINT8 */
1016         DMU_OT_DIRECTORY_CONTENTS,      /* ZAP */
1017         DMU_OT_MASTER_NODE,             /* ZAP */
1018         DMU_OT_UNLINKED_SET,            /* ZAP */
1019         /* zvol: */
1020         DMU_OT_ZVOL,                    /* UINT8 */
1021         DMU_OT_ZVOL_PROP,               /* ZAP */
1022         /* other; for testing only! */
1023         DMU_OT_PLAIN_OTHER,             /* UINT8 */
1024         DMU_OT_UINT64_OTHER,            /* UINT64 */
1025         DMU_OT_ZAP_OTHER,               /* ZAP */
1026         /* new object types: */
1027         DMU_OT_ERROR_LOG,               /* ZAP */
1028         DMU_OT_SPA_HISTORY,             /* UINT8 */
1029         DMU_OT_SPA_HISTORY_OFFSETS,     /* spa_his_phys_t */
1030         DMU_OT_POOL_PROPS,              /* ZAP */
1031         DMU_OT_DSL_PERMS,               /* ZAP */
1032         DMU_OT_ACL,                     /* ACL */
1033         DMU_OT_SYSACL,                  /* SYSACL */
1034         DMU_OT_FUID,                    /* FUID table (Packed NVLIST UINT8) */
1035         DMU_OT_FUID_SIZE,               /* FUID table size UINT64 */
1036         DMU_OT_NEXT_CLONES,             /* ZAP */
1037         DMU_OT_SCAN_QUEUE,              /* ZAP */
1038         DMU_OT_USERGROUP_USED,          /* ZAP */
1039         DMU_OT_USERGROUP_QUOTA,         /* ZAP */
1040         DMU_OT_USERREFS,                /* ZAP */
1041         DMU_OT_DDT_ZAP,                 /* ZAP */
1042         DMU_OT_DDT_STATS,               /* ZAP */
1043         DMU_OT_SA,                      /* System attr */
1044         DMU_OT_SA_MASTER_NODE,          /* ZAP */
1045         DMU_OT_SA_ATTR_REGISTRATION,    /* ZAP */
1046         DMU_OT_SA_ATTR_LAYOUTS,         /* ZAP */
1047         DMU_OT_SCAN_XLATE,              /* ZAP */
1048         DMU_OT_DEDUP,                   /* fake dedup BP from ddt_bp_create() */
1049         DMU_OT_NUMTYPES,
1050
1051         /*
1052          * Names for valid types declared with DMU_OT().
1053          */
1054         DMU_OTN_UINT8_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE),
1055         DMU_OTN_UINT8_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE),
1056         DMU_OTN_UINT16_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE),
1057         DMU_OTN_UINT16_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE),
1058         DMU_OTN_UINT32_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE),
1059         DMU_OTN_UINT32_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE),
1060         DMU_OTN_UINT64_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE),
1061         DMU_OTN_UINT64_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE),
1062         DMU_OTN_ZAP_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE),
1063         DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE)
1064 } dmu_object_type_t;
1065
1066 typedef enum dmu_objset_type {
1067         DMU_OST_NONE,
1068         DMU_OST_META,
1069         DMU_OST_ZFS,
1070         DMU_OST_ZVOL,
1071         DMU_OST_OTHER,                  /* For testing only! */
1072         DMU_OST_ANY,                    /* Be careful! */
1073         DMU_OST_NUMTYPES
1074 } dmu_objset_type_t;
1075
1076 /*
1077  * header for all bonus and spill buffers.
1078  * The header has a fixed portion with a variable number
1079  * of "lengths" depending on the number of variable sized
1080  * attribues which are determined by the "layout number"
1081  */
1082
1083 #define SA_MAGIC        0x2F505A  /* ZFS SA */
1084 typedef struct sa_hdr_phys {
1085         uint32_t sa_magic;
1086         uint16_t sa_layout_info;  /* Encoded with hdrsize and layout number */
1087         uint16_t sa_lengths[1]; /* optional sizes for variable length attrs */
1088         /* ... Data follows the lengths.  */
1089 } sa_hdr_phys_t;
1090
1091 /*
1092  * sa_hdr_phys -> sa_layout_info
1093  *
1094  * 16      10       0
1095  * +--------+-------+
1096  * | hdrsz  |layout |
1097  * +--------+-------+
1098  *
1099  * Bits 0-10 are the layout number
1100  * Bits 11-16 are the size of the header.
1101  * The hdrsize is the number * 8
1102  *
1103  * For example.
1104  * hdrsz of 1 ==> 8 byte header
1105  *          2 ==> 16 byte header
1106  *
1107  */
1108
1109 #define SA_HDR_LAYOUT_NUM(hdr) BF32_GET(hdr->sa_layout_info, 0, 10)
1110 #define SA_HDR_SIZE(hdr) BF32_GET_SB(hdr->sa_layout_info, 10, 16, 3, 0)
1111 #define SA_HDR_LAYOUT_INFO_ENCODE(x, num, size) \
1112 { \
1113         BF32_SET_SB(x, 10, 6, 3, 0, size); \
1114         BF32_SET(x, 0, 10, num); \
1115 }
1116
1117 #define SA_MODE_OFFSET          0
1118 #define SA_SIZE_OFFSET          8
1119 #define SA_GEN_OFFSET           16
1120 #define SA_UID_OFFSET           24
1121 #define SA_GID_OFFSET           32
1122 #define SA_PARENT_OFFSET        40
1123 #define SA_SYMLINK_OFFSET       160
1124
1125 /*
1126  * Intent log header - this on disk structure holds fields to manage
1127  * the log.  All fields are 64 bit to easily handle cross architectures.
1128  */
1129 typedef struct zil_header {
1130         uint64_t zh_claim_txg;  /* txg in which log blocks were claimed */
1131         uint64_t zh_replay_seq; /* highest replayed sequence number */
1132         blkptr_t zh_log;        /* log chain */
1133         uint64_t zh_claim_seq;  /* highest claimed sequence number */
1134         uint64_t zh_pad[5];
1135 } zil_header_t;
1136
1137 #define OBJSET_PHYS_SIZE 2048
1138
1139 typedef struct objset_phys {
1140         dnode_phys_t os_meta_dnode;
1141         zil_header_t os_zil_header;
1142         uint64_t os_type;
1143         uint64_t os_flags;
1144         char os_pad[OBJSET_PHYS_SIZE - sizeof (dnode_phys_t)*3 -
1145             sizeof (zil_header_t) - sizeof (uint64_t)*2];
1146         dnode_phys_t os_userused_dnode;
1147         dnode_phys_t os_groupused_dnode;
1148 } objset_phys_t;
1149
1150 typedef struct dsl_dir_phys {
1151         uint64_t dd_creation_time; /* not actually used */
1152         uint64_t dd_head_dataset_obj;
1153         uint64_t dd_parent_obj;
1154         uint64_t dd_clone_parent_obj;
1155         uint64_t dd_child_dir_zapobj;
1156         /*
1157          * how much space our children are accounting for; for leaf
1158          * datasets, == physical space used by fs + snaps
1159          */
1160         uint64_t dd_used_bytes;
1161         uint64_t dd_compressed_bytes;
1162         uint64_t dd_uncompressed_bytes;
1163         /* Administrative quota setting */
1164         uint64_t dd_quota;
1165         /* Administrative reservation setting */
1166         uint64_t dd_reserved;
1167         uint64_t dd_props_zapobj;
1168         uint64_t dd_pad[21]; /* pad out to 256 bytes for good measure */
1169 } dsl_dir_phys_t;
1170
1171 typedef struct dsl_dataset_phys {
1172         uint64_t ds_dir_obj;
1173         uint64_t ds_prev_snap_obj;
1174         uint64_t ds_prev_snap_txg;
1175         uint64_t ds_next_snap_obj;
1176         uint64_t ds_snapnames_zapobj;   /* zap obj of snaps; ==0 for snaps */
1177         uint64_t ds_num_children;       /* clone/snap children; ==0 for head */
1178         uint64_t ds_creation_time;      /* seconds since 1970 */
1179         uint64_t ds_creation_txg;
1180         uint64_t ds_deadlist_obj;
1181         uint64_t ds_used_bytes;
1182         uint64_t ds_compressed_bytes;
1183         uint64_t ds_uncompressed_bytes;
1184         uint64_t ds_unique_bytes;       /* only relevant to snapshots */
1185         /*
1186          * The ds_fsid_guid is a 56-bit ID that can change to avoid
1187          * collisions.  The ds_guid is a 64-bit ID that will never
1188          * change, so there is a small probability that it will collide.
1189          */
1190         uint64_t ds_fsid_guid;
1191         uint64_t ds_guid;
1192         uint64_t ds_flags;
1193         blkptr_t ds_bp;
1194         uint64_t ds_pad[8]; /* pad out to 320 bytes for good measure */
1195 } dsl_dataset_phys_t;
1196
1197 /*
1198  * The names of zap entries in the DIRECTORY_OBJECT of the MOS.
1199  */
1200 #define DMU_POOL_DIRECTORY_OBJECT       1
1201 #define DMU_POOL_CONFIG                 "config"
1202 #define DMU_POOL_FEATURES_FOR_READ      "features_for_read"
1203 #define DMU_POOL_ROOT_DATASET           "root_dataset"
1204 #define DMU_POOL_SYNC_BPLIST            "sync_bplist"
1205 #define DMU_POOL_ERRLOG_SCRUB           "errlog_scrub"
1206 #define DMU_POOL_ERRLOG_LAST            "errlog_last"
1207 #define DMU_POOL_SPARES                 "spares"
1208 #define DMU_POOL_DEFLATE                "deflate"
1209 #define DMU_POOL_HISTORY                "history"
1210 #define DMU_POOL_PROPS                  "pool_props"
1211
1212 #define ZAP_MAGIC 0x2F52AB2ABULL
1213
1214 #define FZAP_BLOCK_SHIFT(zap)   ((zap)->zap_block_shift)
1215
1216 #define ZAP_MAXCD               (uint32_t)(-1)
1217 #define ZAP_HASHBITS            28
1218 #define MZAP_ENT_LEN            64
1219 #define MZAP_NAME_LEN           (MZAP_ENT_LEN - 8 - 4 - 2)
1220 #define MZAP_MAX_BLKSHIFT       SPA_MAXBLOCKSHIFT
1221 #define MZAP_MAX_BLKSZ          (1 << MZAP_MAX_BLKSHIFT)
1222
1223 typedef struct mzap_ent_phys {
1224         uint64_t mze_value;
1225         uint32_t mze_cd;
1226         uint16_t mze_pad;       /* in case we want to chain them someday */
1227         char mze_name[MZAP_NAME_LEN];
1228 } mzap_ent_phys_t;
1229
1230 typedef struct mzap_phys {
1231         uint64_t mz_block_type; /* ZBT_MICRO */
1232         uint64_t mz_salt;
1233         uint64_t mz_pad[6];
1234         mzap_ent_phys_t mz_chunk[1];
1235         /* actually variable size depending on block size */
1236 } mzap_phys_t;
1237
1238 /*
1239  * The (fat) zap is stored in one object. It is an array of
1240  * 1<<FZAP_BLOCK_SHIFT byte blocks. The layout looks like one of:
1241  *
1242  * ptrtbl fits in first block:
1243  *      [zap_phys_t zap_ptrtbl_shift < 6] [zap_leaf_t] ...
1244  *
1245  * ptrtbl too big for first block:
1246  *      [zap_phys_t zap_ptrtbl_shift >= 6] [zap_leaf_t] [ptrtbl] ...
1247  *
1248  */
1249
1250 #define ZBT_LEAF                ((1ULL << 63) + 0)
1251 #define ZBT_HEADER              ((1ULL << 63) + 1)
1252 #define ZBT_MICRO               ((1ULL << 63) + 3)
1253 /* any other values are ptrtbl blocks */
1254
1255 /*
1256  * the embedded pointer table takes up half a block:
1257  * block size / entry size (2^3) / 2
1258  */
1259 #define ZAP_EMBEDDED_PTRTBL_SHIFT(zap) (FZAP_BLOCK_SHIFT(zap) - 3 - 1)
1260
1261 /*
1262  * The embedded pointer table starts half-way through the block.  Since
1263  * the pointer table itself is half the block, it starts at (64-bit)
1264  * word number (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)).
1265  */
1266 #define ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) \
1267         ((uint64_t *)(zap)->zap_phys) \
1268         [(idx) + (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap))]
1269
1270 /*
1271  * TAKE NOTE:
1272  * If zap_phys_t is modified, zap_byteswap() must be modified.
1273  */
1274 typedef struct zap_phys {
1275         uint64_t zap_block_type;        /* ZBT_HEADER */
1276         uint64_t zap_magic;             /* ZAP_MAGIC */
1277
1278         struct zap_table_phys {
1279                 uint64_t zt_blk;        /* starting block number */
1280                 uint64_t zt_numblks;    /* number of blocks */
1281                 uint64_t zt_shift;      /* bits to index it */
1282                 uint64_t zt_nextblk;    /* next (larger) copy start block */
1283                 uint64_t zt_blks_copied; /* number source blocks copied */
1284         } zap_ptrtbl;
1285
1286         uint64_t zap_freeblk;           /* the next free block */
1287         uint64_t zap_num_leafs;         /* number of leafs */
1288         uint64_t zap_num_entries;       /* number of entries */
1289         uint64_t zap_salt;              /* salt to stir into hash function */
1290         /*
1291          * This structure is followed by padding, and then the embedded
1292          * pointer table.  The embedded pointer table takes up second
1293          * half of the block.  It is accessed using the
1294          * ZAP_EMBEDDED_PTRTBL_ENT() macro.
1295          */
1296 } zap_phys_t;
1297
1298 typedef struct zap_table_phys zap_table_phys_t;
1299
1300 typedef struct fat_zap {
1301         int zap_block_shift;                    /* block size shift */
1302         zap_phys_t *zap_phys;
1303 } fat_zap_t;
1304
1305 #define ZAP_LEAF_MAGIC 0x2AB1EAF
1306
1307 /* chunk size = 24 bytes */
1308 #define ZAP_LEAF_CHUNKSIZE 24
1309
1310 /*
1311  * The amount of space available for chunks is:
1312  * block size (1<<l->l_bs) - hash entry size (2) * number of hash
1313  * entries - header space (2*chunksize)
1314  */
1315 #define ZAP_LEAF_NUMCHUNKS(l) \
1316         (((1<<(l)->l_bs) - 2*ZAP_LEAF_HASH_NUMENTRIES(l)) / \
1317         ZAP_LEAF_CHUNKSIZE - 2)
1318
1319 /*
1320  * The amount of space within the chunk available for the array is:
1321  * chunk size - space for type (1) - space for next pointer (2)
1322  */
1323 #define ZAP_LEAF_ARRAY_BYTES (ZAP_LEAF_CHUNKSIZE - 3)
1324
1325 #define ZAP_LEAF_ARRAY_NCHUNKS(bytes) \
1326         (((bytes)+ZAP_LEAF_ARRAY_BYTES-1)/ZAP_LEAF_ARRAY_BYTES)
1327
1328 /*
1329  * Low water mark:  when there are only this many chunks free, start
1330  * growing the ptrtbl.  Ideally, this should be larger than a
1331  * "reasonably-sized" entry.  20 chunks is more than enough for the
1332  * largest directory entry (MAXNAMELEN (256) byte name, 8-byte value),
1333  * while still being only around 3% for 16k blocks.
1334  */
1335 #define ZAP_LEAF_LOW_WATER (20)
1336
1337 /*
1338  * The leaf hash table has block size / 2^5 (32) number of entries,
1339  * which should be more than enough for the maximum number of entries,
1340  * which is less than block size / CHUNKSIZE (24) / minimum number of
1341  * chunks per entry (3).
1342  */
1343 #define ZAP_LEAF_HASH_SHIFT(l) ((l)->l_bs - 5)
1344 #define ZAP_LEAF_HASH_NUMENTRIES(l) (1 << ZAP_LEAF_HASH_SHIFT(l))
1345
1346 /*
1347  * The chunks start immediately after the hash table.  The end of the
1348  * hash table is at l_hash + HASH_NUMENTRIES, which we simply cast to a
1349  * chunk_t.
1350  */
1351 #define ZAP_LEAF_CHUNK(l, idx) \
1352         ((zap_leaf_chunk_t *) \
1353         ((l)->l_phys->l_hash + ZAP_LEAF_HASH_NUMENTRIES(l)))[idx]
1354 #define ZAP_LEAF_ENTRY(l, idx) (&ZAP_LEAF_CHUNK(l, idx).l_entry)
1355
1356 typedef enum zap_chunk_type {
1357         ZAP_CHUNK_FREE = 253,
1358         ZAP_CHUNK_ENTRY = 252,
1359         ZAP_CHUNK_ARRAY = 251,
1360         ZAP_CHUNK_TYPE_MAX = 250
1361 } zap_chunk_type_t;
1362
1363 /*
1364  * TAKE NOTE:
1365  * If zap_leaf_phys_t is modified, zap_leaf_byteswap() must be modified.
1366  */
1367 typedef struct zap_leaf_phys {
1368         struct zap_leaf_header {
1369                 uint64_t lh_block_type;         /* ZBT_LEAF */
1370                 uint64_t lh_pad1;
1371                 uint64_t lh_prefix;             /* hash prefix of this leaf */
1372                 uint32_t lh_magic;              /* ZAP_LEAF_MAGIC */
1373                 uint16_t lh_nfree;              /* number free chunks */
1374                 uint16_t lh_nentries;           /* number of entries */
1375                 uint16_t lh_prefix_len;         /* num bits used to id this */
1376
1377 /* above is accessable to zap, below is zap_leaf private */
1378
1379                 uint16_t lh_freelist;           /* chunk head of free list */
1380                 uint8_t lh_pad2[12];
1381         } l_hdr; /* 2 24-byte chunks */
1382
1383         /*
1384          * The header is followed by a hash table with
1385          * ZAP_LEAF_HASH_NUMENTRIES(zap) entries.  The hash table is
1386          * followed by an array of ZAP_LEAF_NUMCHUNKS(zap)
1387          * zap_leaf_chunk structures.  These structures are accessed
1388          * with the ZAP_LEAF_CHUNK() macro.
1389          */
1390
1391         uint16_t l_hash[1];
1392 } zap_leaf_phys_t;
1393
1394 typedef union zap_leaf_chunk {
1395         struct zap_leaf_entry {
1396                 uint8_t le_type;                /* always ZAP_CHUNK_ENTRY */
1397                 uint8_t le_value_intlen;        /* size of ints */
1398                 uint16_t le_next;               /* next entry in hash chain */
1399                 uint16_t le_name_chunk;         /* first chunk of the name */
1400                 uint16_t le_name_numints;       /* bytes in name, incl null */
1401                 uint16_t le_value_chunk;        /* first chunk of the value */
1402                 uint16_t le_value_numints;      /* value length in ints */
1403                 uint32_t le_cd;                 /* collision differentiator */
1404                 uint64_t le_hash;               /* hash value of the name */
1405         } l_entry;
1406         struct zap_leaf_array {
1407                 uint8_t la_type;                /* always ZAP_CHUNK_ARRAY */
1408                 uint8_t la_array[ZAP_LEAF_ARRAY_BYTES];
1409                 uint16_t la_next;               /* next blk or CHAIN_END */
1410         } l_array;
1411         struct zap_leaf_free {
1412                 uint8_t lf_type;                /* always ZAP_CHUNK_FREE */
1413                 uint8_t lf_pad[ZAP_LEAF_ARRAY_BYTES];
1414                 uint16_t lf_next;       /* next in free list, or CHAIN_END */
1415         } l_free;
1416 } zap_leaf_chunk_t;
1417
1418 typedef struct zap_leaf {
1419         int l_bs;                       /* block size shift */
1420         zap_leaf_phys_t *l_phys;
1421 } zap_leaf_t;
1422
1423 /*
1424  * Define special zfs pflags
1425  */
1426 #define ZFS_XATTR       0x1             /* is an extended attribute */
1427 #define ZFS_INHERIT_ACE 0x2             /* ace has inheritable ACEs */
1428 #define ZFS_ACL_TRIVIAL 0x4             /* files ACL is trivial */
1429
1430 #define MASTER_NODE_OBJ 1
1431
1432 /*
1433  * special attributes for master node.
1434  */
1435
1436 #define ZFS_FSID                "FSID"
1437 #define ZFS_UNLINKED_SET        "DELETE_QUEUE"
1438 #define ZFS_ROOT_OBJ            "ROOT"
1439 #define ZPL_VERSION_OBJ         "VERSION"
1440 #define ZFS_PROP_BLOCKPERPAGE   "BLOCKPERPAGE"
1441 #define ZFS_PROP_NOGROWBLOCKS   "NOGROWBLOCKS"
1442
1443 #define ZFS_FLAG_BLOCKPERPAGE   0x1
1444 #define ZFS_FLAG_NOGROWBLOCKS   0x2
1445
1446 /*
1447  * ZPL version - rev'd whenever an incompatible on-disk format change
1448  * occurs.  Independent of SPA/DMU/ZAP versioning.
1449  */
1450
1451 #define ZPL_VERSION             1ULL
1452
1453 /*
1454  * The directory entry has the type (currently unused on Solaris) in the
1455  * top 4 bits, and the object number in the low 48 bits.  The "middle"
1456  * 12 bits are unused.
1457  */
1458 #define ZFS_DIRENT_TYPE(de) BF64_GET(de, 60, 4)
1459 #define ZFS_DIRENT_OBJ(de) BF64_GET(de, 0, 48)
1460 #define ZFS_DIRENT_MAKE(type, obj) (((uint64_t)type << 60) | obj)
1461
1462 typedef struct ace {
1463         uid_t           a_who;          /* uid or gid */
1464         uint32_t        a_access_mask;  /* read,write,... */
1465         uint16_t        a_flags;        /* see below */
1466         uint16_t        a_type;         /* allow or deny */
1467 } ace_t;
1468
1469 #define ACE_SLOT_CNT    6
1470
1471 typedef struct zfs_znode_acl {
1472         uint64_t        z_acl_extern_obj;         /* ext acl pieces */
1473         uint32_t        z_acl_count;              /* Number of ACEs */
1474         uint16_t        z_acl_version;            /* acl version */
1475         uint16_t        z_acl_pad;                /* pad */
1476         ace_t           z_ace_data[ACE_SLOT_CNT]; /* 6 standard ACEs */
1477 } zfs_znode_acl_t;
1478
1479 /*
1480  * This is the persistent portion of the znode.  It is stored
1481  * in the "bonus buffer" of the file.  Short symbolic links
1482  * are also stored in the bonus buffer.
1483  */
1484 typedef struct znode_phys {
1485         uint64_t zp_atime[2];           /*  0 - last file access time */
1486         uint64_t zp_mtime[2];           /* 16 - last file modification time */
1487         uint64_t zp_ctime[2];           /* 32 - last file change time */
1488         uint64_t zp_crtime[2];          /* 48 - creation time */
1489         uint64_t zp_gen;                /* 64 - generation (txg of creation) */
1490         uint64_t zp_mode;               /* 72 - file mode bits */
1491         uint64_t zp_size;               /* 80 - size of file */
1492         uint64_t zp_parent;             /* 88 - directory parent (`..') */
1493         uint64_t zp_links;              /* 96 - number of links to file */
1494         uint64_t zp_xattr;              /* 104 - DMU object for xattrs */
1495         uint64_t zp_rdev;               /* 112 - dev_t for VBLK & VCHR files */
1496         uint64_t zp_flags;              /* 120 - persistent flags */
1497         uint64_t zp_uid;                /* 128 - file owner */
1498         uint64_t zp_gid;                /* 136 - owning group */
1499         uint64_t zp_pad[4];             /* 144 - future */
1500         zfs_znode_acl_t zp_acl;         /* 176 - 263 ACL */
1501         /*
1502          * Data may pad out any remaining bytes in the znode buffer, eg:
1503          *
1504          * |<---------------------- dnode_phys (512) ------------------------>|
1505          * |<-- dnode (192) --->|<----------- "bonus" buffer (320) ---------->|
1506          *                      |<---- znode (264) ---->|<---- data (56) ---->|
1507          *
1508          * At present, we only use this space to store symbolic links.
1509          */
1510 } znode_phys_t;
1511
1512 /*
1513  * In-core vdev representation.
1514  */
1515 struct vdev;
1516 typedef int vdev_phys_read_t(struct vdev *vdev, void *priv,
1517     off_t offset, void *buf, size_t bytes);
1518 typedef int vdev_read_t(struct vdev *vdev, const blkptr_t *bp,
1519     void *buf, off_t offset, size_t bytes);
1520
1521 typedef STAILQ_HEAD(vdev_list, vdev) vdev_list_t;
1522
1523 typedef struct vdev {
1524         STAILQ_ENTRY(vdev) v_childlink; /* link in parent's child list */
1525         STAILQ_ENTRY(vdev) v_alllink;   /* link in global vdev list */
1526         vdev_list_t     v_children;     /* children of this vdev */
1527         const char      *v_name;        /* vdev name */
1528         const char      *v_phys_path;   /* vdev bootpath */
1529         const char      *v_devid;       /* vdev devid */
1530         uint64_t        v_guid;         /* vdev guid */
1531         int             v_id;           /* index in parent */
1532         int             v_ashift;       /* offset to block shift */
1533         int             v_nparity;      /* # parity for raidz */
1534         struct vdev     *v_top;         /* parent vdev */
1535         int             v_nchildren;    /* # children */
1536         vdev_state_t    v_state;        /* current state */
1537         vdev_phys_read_t *v_phys_read;  /* read from raw leaf vdev */
1538         vdev_read_t     *v_read;        /* read from vdev */
1539         void            *v_read_priv;   /* private data for read function */
1540 } vdev_t;
1541
1542 /*
1543  * In-core pool representation.
1544  */
1545 typedef STAILQ_HEAD(spa_list, spa) spa_list_t;
1546
1547 typedef struct spa {
1548         STAILQ_ENTRY(spa) spa_link;     /* link in global pool list */
1549         char            *spa_name;      /* pool name */
1550         uint64_t        spa_guid;       /* pool guid */
1551         uint64_t        spa_txg;        /* most recent transaction */
1552         struct uberblock spa_uberblock; /* best uberblock so far */
1553         vdev_list_t     spa_vdevs;      /* list of all toplevel vdevs */
1554         objset_phys_t   spa_mos;        /* MOS for this pool */
1555         int             spa_inited;     /* initialized */
1556         vdev_t          *spa_boot_vdev; /* boot device for kernel */
1557 } spa_t;
1558
1559 static void decode_embedded_bp_compressed(const blkptr_t *, void *);