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 | 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 unused 154 * lvl level of indirection 155 * type DMU object type 156 * phys birth txg of block allocation; zero if same as logical birth txg 157 * log. birth transaction group in which the block was logically born 158 * fill count number of non-zero blocks under this bp 159 * checksum[4] 256-bit checksum of the data this bp describes 160 */ 161 #define SPA_BLKPTRSHIFT 7 /* blkptr_t is 128 bytes */ 162 #define SPA_DVAS_PER_BP 3 /* Number of DVAs in a bp */ 163 164 typedef struct blkptr { 165 dva_t blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */ 166 uint64_t blk_prop; /* size, compression, type, etc */ 167 uint64_t blk_pad[2]; /* Extra space for the future */ 168 uint64_t blk_phys_birth; /* txg when block was allocated */ 169 uint64_t blk_birth; /* transaction group at birth */ 170 uint64_t blk_fill; /* fill count */ 171 zio_cksum_t blk_cksum; /* 256-bit checksum */ 172 } blkptr_t; 173 174 /* 175 * Macros to get and set fields in a bp or DVA. 176 */ 177 #define DVA_GET_ASIZE(dva) \ 178 BF64_GET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, SPA_MINBLOCKSHIFT, 0) 179 #define DVA_SET_ASIZE(dva, x) \ 180 BF64_SET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, \ 181 SPA_MINBLOCKSHIFT, 0, x) 182 183 #define DVA_GET_GRID(dva) BF64_GET((dva)->dva_word[0], 24, 8) 184 #define DVA_SET_GRID(dva, x) BF64_SET((dva)->dva_word[0], 24, 8, x) 185 186 #define DVA_GET_VDEV(dva) BF64_GET((dva)->dva_word[0], 32, 32) 187 #define DVA_SET_VDEV(dva, x) BF64_SET((dva)->dva_word[0], 32, 32, x) 188 189 #define DVA_GET_OFFSET(dva) \ 190 BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0) 191 #define DVA_SET_OFFSET(dva, x) \ 192 BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x) 193 194 #define DVA_GET_GANG(dva) BF64_GET((dva)->dva_word[1], 63, 1) 195 #define DVA_SET_GANG(dva, x) BF64_SET((dva)->dva_word[1], 63, 1, x) 196 197 #define BP_GET_LSIZE(bp) \ 198 BF64_GET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1) 199 #define BP_SET_LSIZE(bp, x) \ 200 BF64_SET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x) 201 202 #define BP_GET_PSIZE(bp) \ 203 BF64_GET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1) 204 #define BP_SET_PSIZE(bp, x) \ 205 BF64_SET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1, x) 206 207 #define BP_GET_COMPRESS(bp) BF64_GET((bp)->blk_prop, 32, 8) 208 #define BP_SET_COMPRESS(bp, x) BF64_SET((bp)->blk_prop, 32, 8, x) 209 210 #define BP_GET_CHECKSUM(bp) BF64_GET((bp)->blk_prop, 40, 8) 211 #define BP_SET_CHECKSUM(bp, x) BF64_SET((bp)->blk_prop, 40, 8, x) 212 213 #define BP_GET_TYPE(bp) BF64_GET((bp)->blk_prop, 48, 8) 214 #define BP_SET_TYPE(bp, x) BF64_SET((bp)->blk_prop, 48, 8, x) 215 216 #define BP_GET_LEVEL(bp) BF64_GET((bp)->blk_prop, 56, 5) 217 #define BP_SET_LEVEL(bp, x) BF64_SET((bp)->blk_prop, 56, 5, x) 218 219 #define BP_GET_DEDUP(bp) BF64_GET((bp)->blk_prop, 62, 1) 220 #define BP_SET_DEDUP(bp, x) BF64_SET((bp)->blk_prop, 62, 1, x) 221 222 #define BP_GET_BYTEORDER(bp) BF64_GET((bp)->blk_prop, 63, 1) 223 #define BP_SET_BYTEORDER(bp, x) BF64_SET((bp)->blk_prop, 63, 1, x) 224 225 #define BP_PHYSICAL_BIRTH(bp) \ 226 ((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth) 227 228 #define BP_SET_BIRTH(bp, logical, physical) \ 229 { \ 230 (bp)->blk_birth = (logical); \ 231 (bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \ 232 } 233 234 #define BP_GET_ASIZE(bp) \ 235 (DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \ 236 DVA_GET_ASIZE(&(bp)->blk_dva[2])) 237 238 #define BP_GET_UCSIZE(bp) \ 239 ((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \ 240 BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp)); 241 242 #define BP_GET_NDVAS(bp) \ 243 (!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \ 244 !!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \ 245 !!DVA_GET_ASIZE(&(bp)->blk_dva[2])) 246 247 #define DVA_EQUAL(dva1, dva2) \ 248 ((dva1)->dva_word[1] == (dva2)->dva_word[1] && \ 249 (dva1)->dva_word[0] == (dva2)->dva_word[0]) 250 251 #define BP_EQUAL(bp1, bp2) \ 252 (BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) && \ 253 DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) && \ 254 DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) && \ 255 DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2])) 256 257 #define ZIO_CHECKSUM_EQUAL(zc1, zc2) \ 258 (0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \ 259 ((zc1).zc_word[1] - (zc2).zc_word[1]) | \ 260 ((zc1).zc_word[2] - (zc2).zc_word[2]) | \ 261 ((zc1).zc_word[3] - (zc2).zc_word[3]))) 262 263 #define DVA_IS_VALID(dva) (DVA_GET_ASIZE(dva) != 0) 264 265 #define ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3) \ 266 { \ 267 (zcp)->zc_word[0] = w0; \ 268 (zcp)->zc_word[1] = w1; \ 269 (zcp)->zc_word[2] = w2; \ 270 (zcp)->zc_word[3] = w3; \ 271 } 272 273 #define BP_IDENTITY(bp) (&(bp)->blk_dva[0]) 274 #define BP_IS_GANG(bp) DVA_GET_GANG(BP_IDENTITY(bp)) 275 #define DVA_IS_EMPTY(dva) ((dva)->dva_word[0] == 0ULL && \ 276 (dva)->dva_word[1] == 0ULL) 277 #define BP_IS_HOLE(bp) DVA_IS_EMPTY(BP_IDENTITY(bp)) 278 279 /* BP_IS_RAIDZ(bp) assumes no block compression */ 280 #define BP_IS_RAIDZ(bp) (DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \ 281 BP_GET_PSIZE(bp)) 282 283 #define BP_ZERO(bp) \ 284 { \ 285 (bp)->blk_dva[0].dva_word[0] = 0; \ 286 (bp)->blk_dva[0].dva_word[1] = 0; \ 287 (bp)->blk_dva[1].dva_word[0] = 0; \ 288 (bp)->blk_dva[1].dva_word[1] = 0; \ 289 (bp)->blk_dva[2].dva_word[0] = 0; \ 290 (bp)->blk_dva[2].dva_word[1] = 0; \ 291 (bp)->blk_prop = 0; \ 292 (bp)->blk_pad[0] = 0; \ 293 (bp)->blk_pad[1] = 0; \ 294 (bp)->blk_phys_birth = 0; \ 295 (bp)->blk_birth = 0; \ 296 (bp)->blk_fill = 0; \ 297 ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0); \ 298 } 299 300 #ifdef _BIG_ENDIAN 301 #define ZFS_HOST_BYTEORDER (0ULL) 302 #else 303 #define ZFS_HOST_BYTEORDER (1ULL) 304 #endif 305 306 #define BP_SHOULD_BYTESWAP(bp) (BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER) 307 308 #define BP_SPRINTF_LEN 320 309 310 #endif /* _SYS_SPA_H */ 311