1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * GRUB -- GRand Unified Bootloader 4 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc. 5 */ 6 /* 7 * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved. 8 */ 9 10 #ifndef ZFS_SPA_HEADER 11 #define ZFS_SPA_HEADER 1 12 13 14 /* 15 * General-purpose 32-bit and 64-bit bitfield encodings. 16 */ 17 #define BF32_DECODE(x, low, len) P2PHASE((x) >> (low), 1U << (len)) 18 #define BF64_DECODE(x, low, len) P2PHASE((x) >> (low), 1ULL << (len)) 19 #define BF32_ENCODE(x, low, len) (P2PHASE((x), 1U << (len)) << (low)) 20 #define BF64_ENCODE(x, low, len) (P2PHASE((x), 1ULL << (len)) << (low)) 21 22 #define BF32_GET(x, low, len) BF32_DECODE(x, low, len) 23 #define BF64_GET(x, low, len) BF64_DECODE(x, low, len) 24 25 #define BF32_SET(x, low, len, val) \ 26 ((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len)) 27 #define BF64_SET(x, low, len, val) \ 28 ((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len)) 29 30 #define BF32_GET_SB(x, low, len, shift, bias) \ 31 ((BF32_GET(x, low, len) + (bias)) << (shift)) 32 #define BF64_GET_SB(x, low, len, shift, bias) \ 33 ((BF64_GET(x, low, len) + (bias)) << (shift)) 34 35 #define BF32_SET_SB(x, low, len, shift, bias, val) \ 36 BF32_SET(x, low, len, ((val) >> (shift)) - (bias)) 37 #define BF64_SET_SB(x, low, len, shift, bias, val) \ 38 BF64_SET(x, low, len, ((val) >> (shift)) - (bias)) 39 40 /* 41 * We currently support nine block sizes, from 512 bytes to 128K. 42 * We could go higher, but the benefits are near-zero and the cost 43 * of COWing a giant block to modify one byte would become excessive. 44 */ 45 #define SPA_MINBLOCKSHIFT 9 46 #define SPA_MAXBLOCKSHIFT 17 47 #define SPA_MINBLOCKSIZE (1ULL << SPA_MINBLOCKSHIFT) 48 #define SPA_MAXBLOCKSIZE (1ULL << SPA_MAXBLOCKSHIFT) 49 50 #define SPA_BLOCKSIZES (SPA_MAXBLOCKSHIFT - SPA_MINBLOCKSHIFT + 1) 51 52 /* 53 * Size of block to hold the configuration data (a packed nvlist) 54 */ 55 #define SPA_CONFIG_BLOCKSIZE (1 << 14) 56 57 /* 58 * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB. 59 * The ASIZE encoding should be at least 64 times larger (6 more bits) 60 * to support up to 4-way RAID-Z mirror mode with worst-case gang block 61 * overhead, three DVAs per bp, plus one more bit in case we do anything 62 * else that expands the ASIZE. 63 */ 64 #define SPA_LSIZEBITS 16 /* LSIZE up to 32M (2^16 * 512) */ 65 #define SPA_PSIZEBITS 16 /* PSIZE up to 32M (2^16 * 512) */ 66 #define SPA_ASIZEBITS 24 /* ASIZE up to 64 times larger */ 67 68 /* 69 * All SPA data is represented by 128-bit data virtual addresses (DVAs). 70 * The members of the dva_t should be considered opaque outside the SPA. 71 */ 72 typedef struct dva { 73 uint64_t dva_word[2]; 74 } dva_t; 75 76 /* 77 * Each block has a 256-bit checksum -- strong enough for cryptographic hashes. 78 */ 79 typedef struct zio_cksum { 80 uint64_t zc_word[4]; 81 } zio_cksum_t; 82 83 /* 84 * Each block is described by its DVAs, time of birth, checksum, etc. 85 * The word-by-word, bit-by-bit layout of the blkptr is as follows: 86 * 87 * 64 56 48 40 32 24 16 8 0 88 * +-------+-------+-------+-------+-------+-------+-------+-------+ 89 * 0 | vdev1 | GRID | ASIZE | 90 * +-------+-------+-------+-------+-------+-------+-------+-------+ 91 * 1 |G| offset1 | 92 * +-------+-------+-------+-------+-------+-------+-------+-------+ 93 * 2 | vdev2 | GRID | ASIZE | 94 * +-------+-------+-------+-------+-------+-------+-------+-------+ 95 * 3 |G| offset2 | 96 * +-------+-------+-------+-------+-------+-------+-------+-------+ 97 * 4 | vdev3 | GRID | ASIZE | 98 * +-------+-------+-------+-------+-------+-------+-------+-------+ 99 * 5 |G| offset3 | 100 * +-------+-------+-------+-------+-------+-------+-------+-------+ 101 * 6 |BDX|lvl| type | cksum | comp | PSIZE | LSIZE | 102 * +-------+-------+-------+-------+-------+-------+-------+-------+ 103 * 7 | padding | 104 * +-------+-------+-------+-------+-------+-------+-------+-------+ 105 * 8 | padding | 106 * +-------+-------+-------+-------+-------+-------+-------+-------+ 107 * 9 | physical birth txg | 108 * +-------+-------+-------+-------+-------+-------+-------+-------+ 109 * a | logical birth txg | 110 * +-------+-------+-------+-------+-------+-------+-------+-------+ 111 * b | fill count | 112 * +-------+-------+-------+-------+-------+-------+-------+-------+ 113 * c | checksum[0] | 114 * +-------+-------+-------+-------+-------+-------+-------+-------+ 115 * d | checksum[1] | 116 * +-------+-------+-------+-------+-------+-------+-------+-------+ 117 * e | checksum[2] | 118 * +-------+-------+-------+-------+-------+-------+-------+-------+ 119 * f | checksum[3] | 120 * +-------+-------+-------+-------+-------+-------+-------+-------+ 121 * 122 * Legend: 123 * 124 * vdev virtual device ID 125 * offset offset into virtual device 126 * LSIZE logical size 127 * PSIZE physical size (after compression) 128 * ASIZE allocated size (including RAID-Z parity and gang block headers) 129 * GRID RAID-Z layout information (reserved for future use) 130 * cksum checksum function 131 * comp compression function 132 * G gang block indicator 133 * B byteorder (endianness) 134 * D dedup 135 * X unused 136 * lvl level of indirection 137 * type DMU object type 138 * phys birth txg of block allocation; zero if same as logical birth txg 139 * log. birth transaction group in which the block was logically born 140 * fill count number of non-zero blocks under this bp 141 * checksum[4] 256-bit checksum of the data this bp describes 142 */ 143 #define SPA_BLKPTRSHIFT 7 /* blkptr_t is 128 bytes */ 144 #define SPA_DVAS_PER_BP 3 /* Number of DVAs in a bp */ 145 146 typedef struct blkptr { 147 dva_t blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */ 148 uint64_t blk_prop; /* size, compression, type, etc */ 149 uint64_t blk_pad[2]; /* Extra space for the future */ 150 uint64_t blk_phys_birth; /* txg when block was allocated */ 151 uint64_t blk_birth; /* transaction group at birth */ 152 uint64_t blk_fill; /* fill count */ 153 zio_cksum_t blk_cksum; /* 256-bit checksum */ 154 } blkptr_t; 155 156 /* 157 * Macros to get and set fields in a bp or DVA. 158 */ 159 #define DVA_GET_ASIZE(dva) \ 160 BF64_GET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0) 161 #define DVA_SET_ASIZE(dva, x) \ 162 BF64_SET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0, x) 163 164 #define DVA_GET_GRID(dva) BF64_GET((dva)->dva_word[0], 24, 8) 165 #define DVA_SET_GRID(dva, x) BF64_SET((dva)->dva_word[0], 24, 8, x) 166 167 #define DVA_GET_VDEV(dva) BF64_GET((dva)->dva_word[0], 32, 32) 168 #define DVA_SET_VDEV(dva, x) BF64_SET((dva)->dva_word[0], 32, 32, x) 169 170 #define DVA_GET_GANG(dva) BF64_GET((dva)->dva_word[1], 63, 1) 171 #define DVA_SET_GANG(dva, x) BF64_SET((dva)->dva_word[1], 63, 1, x) 172 173 #define BP_GET_LSIZE(bp) \ 174 BF64_GET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1) 175 #define BP_SET_LSIZE(bp, x) \ 176 BF64_SET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1, x) 177 178 #define BP_GET_COMPRESS(bp) BF64_GET((bp)->blk_prop, 32, 8) 179 #define BP_SET_COMPRESS(bp, x) BF64_SET((bp)->blk_prop, 32, 8, x) 180 181 #define BP_GET_CHECKSUM(bp) BF64_GET((bp)->blk_prop, 40, 8) 182 #define BP_SET_CHECKSUM(bp, x) BF64_SET((bp)->blk_prop, 40, 8, x) 183 184 #define BP_GET_TYPE(bp) BF64_GET((bp)->blk_prop, 48, 8) 185 #define BP_SET_TYPE(bp, x) BF64_SET((bp)->blk_prop, 48, 8, x) 186 187 #define BP_GET_LEVEL(bp) BF64_GET((bp)->blk_prop, 56, 5) 188 #define BP_SET_LEVEL(bp, x) BF64_SET((bp)->blk_prop, 56, 5, x) 189 190 #define BP_GET_PROP_BIT_61(bp) BF64_GET((bp)->blk_prop, 61, 1) 191 #define BP_SET_PROP_BIT_61(bp, x) BF64_SET((bp)->blk_prop, 61, 1, x) 192 193 #define BP_GET_DEDUP(bp) BF64_GET((bp)->blk_prop, 62, 1) 194 #define BP_SET_DEDUP(bp, x) BF64_SET((bp)->blk_prop, 62, 1, x) 195 196 #define BP_GET_BYTEORDER(bp) (0 - BF64_GET((bp)->blk_prop, 63, 1)) 197 #define BP_SET_BYTEORDER(bp, x) BF64_SET((bp)->blk_prop, 63, 1, x) 198 199 #define BP_PHYSICAL_BIRTH(bp) \ 200 ((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth) 201 202 #define BP_SET_BIRTH(bp, logical, physical) \ 203 { \ 204 (bp)->blk_birth = (logical); \ 205 (bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \ 206 } 207 208 #define BP_GET_ASIZE(bp) \ 209 (DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \ 210 DVA_GET_ASIZE(&(bp)->blk_dva[2])) 211 212 #define BP_GET_UCSIZE(bp) \ 213 ((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \ 214 BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp)); 215 216 #define BP_GET_NDVAS(bp) \ 217 (!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \ 218 !!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \ 219 !!DVA_GET_ASIZE(&(bp)->blk_dva[2])) 220 221 #define BP_COUNT_GANG(bp) \ 222 (DVA_GET_GANG(&(bp)->blk_dva[0]) + \ 223 DVA_GET_GANG(&(bp)->blk_dva[1]) + \ 224 DVA_GET_GANG(&(bp)->blk_dva[2])) 225 226 #define DVA_EQUAL(dva1, dva2) \ 227 ((dva1)->dva_word[1] == (dva2)->dva_word[1] && \ 228 (dva1)->dva_word[0] == (dva2)->dva_word[0]) 229 230 #define BP_EQUAL(bp1, bp2) \ 231 (BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) && \ 232 DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) && \ 233 DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) && \ 234 DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2])) 235 236 #define ZIO_CHECKSUM_EQUAL(zc1, zc2) \ 237 (0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \ 238 ((zc1).zc_word[1] - (zc2).zc_word[1]) | \ 239 ((zc1).zc_word[2] - (zc2).zc_word[2]) | \ 240 ((zc1).zc_word[3] - (zc2).zc_word[3]))) 241 242 #define DVA_IS_VALID(dva) (DVA_GET_ASIZE(dva) != 0) 243 244 #define ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3) \ 245 { \ 246 (zcp)->zc_word[0] = w0; \ 247 (zcp)->zc_word[1] = w1; \ 248 (zcp)->zc_word[2] = w2; \ 249 (zcp)->zc_word[3] = w3; \ 250 } 251 252 #define BP_IDENTITY(bp) (&(bp)->blk_dva[0]) 253 #define BP_IS_GANG(bp) DVA_GET_GANG(BP_IDENTITY(bp)) 254 #define BP_IS_HOLE(bp) ((bp)->blk_birth == 0) 255 256 /* BP_IS_RAIDZ(bp) assumes no block compression */ 257 #define BP_IS_RAIDZ(bp) (DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \ 258 BP_GET_PSIZE(bp)) 259 260 #define BP_ZERO(bp) \ 261 { \ 262 (bp)->blk_dva[0].dva_word[0] = 0; \ 263 (bp)->blk_dva[0].dva_word[1] = 0; \ 264 (bp)->blk_dva[1].dva_word[0] = 0; \ 265 (bp)->blk_dva[1].dva_word[1] = 0; \ 266 (bp)->blk_dva[2].dva_word[0] = 0; \ 267 (bp)->blk_dva[2].dva_word[1] = 0; \ 268 (bp)->blk_prop = 0; \ 269 (bp)->blk_pad[0] = 0; \ 270 (bp)->blk_pad[1] = 0; \ 271 (bp)->blk_phys_birth = 0; \ 272 (bp)->blk_birth = 0; \ 273 (bp)->blk_fill = 0; \ 274 ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0); \ 275 } 276 277 #define BP_SPRINTF_LEN 320 278 279 #endif /* ! ZFS_SPA_HEADER */ 280