1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * CDDL HEADER START 4 * 5 * The contents of this file are subject to the terms of the 6 * Common Development and Distribution License (the "License"). 7 * You may not use this file except in compliance with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or https://opensource.org/licenses/CDDL-1.0. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 2018 Intel Corporation. 24 * Copyright (c) 2020 by Lawrence Livermore National Security, LLC. 25 * Copyright (c) 2025, Klara, Inc. 26 * Copyright (c) 2026, Seagate Technology, LLC. 27 * Copyright (c) 2026, Wasabi Technologies, Inc. 28 */ 29 30 #include <sys/zfs_context.h> 31 #include <sys/spa.h> 32 #include <sys/spa_impl.h> 33 #include <sys/vdev_impl.h> 34 #include <sys/vdev_draid.h> 35 #include <sys/vdev_raidz.h> 36 #include <sys/vdev_rebuild.h> 37 #include <sys/abd.h> 38 #include <sys/zio.h> 39 #include <sys/nvpair.h> 40 #include <sys/zio_checksum.h> 41 #include <sys/fs/zfs.h> 42 #include <sys/fm/fs/zfs.h> 43 #include <zfs_fletcher.h> 44 45 #ifdef ZFS_DEBUG 46 #include <sys/vdev.h> /* For vdev_xlate() in vdev_draid_io_verify() */ 47 #endif 48 49 /* 50 * dRAID is a distributed spare implementation for ZFS. A dRAID vdev is 51 * comprised of multiple raidz redundancy groups which are spread over the 52 * dRAID children. To ensure an even distribution, and avoid hot spots, a 53 * permutation mapping is applied to the order of the dRAID children. 54 * This mixing effectively distributes the parity columns evenly over all 55 * of the disks in the dRAID. 56 * 57 * This is beneficial because it means when resilvering all of the disks 58 * can participate thereby increasing the available IOPs and bandwidth. 59 * Furthermore, by reserving a small fraction of each child's total capacity 60 * virtual distributed spare disks can be created. These spares similarly 61 * benefit from the performance gains of spanning all of the children. The 62 * consequence of which is that resilvering to a distributed spare can 63 * substantially reduce the time required to restore full parity to pool 64 * with a failed disks. 65 * 66 * === dRAID group layout === 67 * 68 * First, let's define a "row" in the configuration to be a 16M chunk from 69 * each physical drive at the same offset. This is the minimum allowable 70 * size since it must be possible to store a full 16M block when there is 71 * only a single data column. Next, we define a "group" to be a set of 72 * sequential disks containing both the parity and data columns. We allow 73 * groups to span multiple rows in order to align any group size to any 74 * number of physical drives. Finally, a "slice" is comprised of the rows 75 * which contain the target number of groups. The permutation mappings 76 * are applied in a round robin fashion to each slice. 77 * 78 * Given D+P drives in a group (including parity drives) and C-S physical 79 * drives (not including the spare drives), we can distribute the groups 80 * across R rows without remainder by selecting the least common multiple 81 * of D+P and C-S as the number of groups; i.e. ngroups = LCM(D+P, C-S). 82 * 83 * In the example below, there are C=14 physical drives in the configuration 84 * with S=2 drives worth of spare capacity. Each group has a width of 9 85 * which includes D=8 data and P=1 parity drive. There are 4 groups and 86 * 3 rows per slice. Each group has a size of 144M (16M * 9) and a slice 87 * size is 576M (144M * 4). When allocating from a dRAID each group is 88 * filled before moving on to the next as show in slice0 below. 89 * 90 * data disks (8 data + 1 parity) spares (2) 91 * +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 92 * ^ | 2 | 6 | 1 | 11| 4 | 0 | 7 | 10| 8 | 9 | 13| 5 | 12| 3 | device map 0 93 * | +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 94 * | | group 0 | group 1..| | 95 * | +-----------------------------------+-----------+-------| 96 * | | 0 1 2 3 4 5 6 7 8 | 36 37 38| | r 97 * | | 9 10 11 12 13 14 15 16 17| 45 46 47| | o 98 * | | 18 19 20 21 22 23 24 25 26| 54 55 56| | w 99 * | 27 28 29 30 31 32 33 34 35| 63 64 65| | 0 100 * s +-----------------------+-----------------------+-------+ 101 * l | ..group 1 | group 2.. | | 102 * i +-----------------------+-----------------------+-------+ 103 * c | 39 40 41 42 43 44| 72 73 74 75 76 77| | r 104 * e | 48 49 50 51 52 53| 81 82 83 84 85 86| | o 105 * 0 | 57 58 59 60 61 62| 90 91 92 93 94 95| | w 106 * | 66 67 68 69 70 71| 99 100 101 102 103 104| | 1 107 * | +-----------+-----------+-----------------------+-------+ 108 * | |..group 2 | group 3 | | 109 * | +-----------+-----------+-----------------------+-------+ 110 * | | 78 79 80|108 109 110 111 112 113 114 115 116| | r 111 * | | 87 88 89|117 118 119 120 121 122 123 124 125| | o 112 * | | 96 97 98|126 127 128 129 130 131 132 133 134| | w 113 * v |105 106 107|135 136 137 138 139 140 141 142 143| | 2 114 * +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 115 * | 9 | 11| 12| 2 | 4 | 1 | 3 | 0 | 10| 13| 8 | 5 | 6 | 7 | device map 1 116 * s +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 117 * l | group 4 | group 5..| | row 3 118 * i +-----------------------+-----------+-----------+-------| 119 * c | ..group 5 | group 6.. | | row 4 120 * e +-----------+-----------+-----------------------+-------+ 121 * 1 |..group 6 | group 7 | | row 5 122 * +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 123 * | 3 | 5 | 10| 8 | 6 | 11| 12| 0 | 2 | 4 | 7 | 1 | 9 | 13| device map 2 124 * s +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 125 * l | group 8 | group 9..| | row 6 126 * i +-----------------------------------------------+-------| 127 * c | ..group 9 | group 10.. | | row 7 128 * e +-----------------------+-----------------------+-------+ 129 * 2 |..group 10 | group 11 | | row 8 130 * +-----------+-----------------------------------+-------+ 131 * 132 * This layout has several advantages over requiring that each row contain 133 * a whole number of groups. 134 * 135 * 1. The group count is not a relevant parameter when defining a dRAID 136 * layout. Only the group width is needed, and *all* groups will have 137 * the desired size. 138 * 139 * 2. All possible group widths (<= physical disk count) can be supported. 140 * 141 * 3. The logic within vdev_draid.c is simplified when the group width is 142 * the same for all groups (although some of the logic around computing 143 * permutation numbers and drive offsets is more complicated). 144 * 145 * === dRAID failure domains === 146 * 147 * If we put several slices alongside in a row and configure each disk in 148 * slice to be from different failure domain (for example an enclosure), we 149 * can then tolerate the failure of the whole domain -- only one device 150 * will be failed in every slice in this case. The column of such slices 151 * we will call failure group, and the row with such slices alongside we 152 * will call "big width row", width being multiple of children (W = C*n). 153 * 154 * Here's an example of configuration with 7 failure domains and two 155 * failure groups: 156 * 157 * 7 C disks in each slice, 2 slices in big 14 W rows 158 * +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 159 * | 1 | 7 | 3 | 9 | 11| 5 | 13| 6 | 10| 4 | 8 | 0 | 12| 2 | device map 0 160 * s +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 161 * l | group 0 | gr1..| S | group 3 | gr4.. | S | row 0 162 * c +-------+-------+-------+---+-------+-------+-------+---+ 163 * 0,1 | ..gr1 | group 2 | S | ..gr4 | group 5 | S | row 1 164 * +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 165 * | 2 | 10| 12| 7 | 8 | 13| 11| 1 | 5 | 4 | 6 | 3 | 9 | 0 | device map 1 166 * s +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ 167 * l | group 6 | gr7..| S | group 9 |gr10.. | S | row 2 168 * c +-------+-------+-------+---+---------------+-------+---+ 169 * 2,3 | ..gr7 | group 8 | S |..gr10 | group 11 | S | row 3 170 * +-------+---------------+---+-------+---------------+---+ 171 * failure group 0 failure group 1 172 * 173 * In practice, there might be much more failure groups. And in theory, the 174 * width of the big rows can be much larger than curent limit of 255 imposed 175 * for the number of children. But we kept the same limit for now for the 176 * sake of simplicity of implementation. 177 * 178 * In order to preserve fast sequential resilvering in case of a disk failure, 179 * all failure groups much share all disks between themselves, and this is 180 * achieved by shuffling the disks between the groups. But only i-th disks 181 * in each group are shuffled between themselves, i.e. the disks from the 182 * same failure domains (enclosures). After that, they are shuffled within 183 * each group. Thus, no more than one disk from any failure domain can appear 184 * in any failure group as a result of this shuffling. In the above example, 185 * you won't find any tuple of (0, 7) or (1, 8) or (2, 9) or ... (6, 13) 186 * mapped to the same slice. This is done in vdev_draid_shuffle_perms(). 187 * 188 * Spare disks are evenly distributed among failure groups, and they are 189 * shared by all groups. However, to support domain failure, we cannot have 190 * more than (nparity - 1) failed disks in any group, no matter if they are 191 * rebuilt to draid spares or not (the blocks of those spares can be mapped 192 * to the disks from the failed domain (enclosure), and we cannot tolerate 193 * more than nparity failures in any failure group). 194 * 195 * 196 * N.B. The following array describes all valid dRAID permutation maps. 197 * Each row is used to generate a permutation map for a different number 198 * of children from a unique seed. The seeds were generated and carefully 199 * evaluated by the 'draid' utility in order to provide balanced mappings. 200 * In addition to the seed a checksum of the in-memory mapping is stored 201 * for verification. 202 * 203 * The imbalance ratio of a given failure (e.g. 5 disks wide, child 3 failed, 204 * with a given permutation map) is the ratio of the amounts of I/O that will 205 * be sent to the least and most busy disks when resilvering. The average 206 * imbalance ratio (of a given number of disks and permutation map) is the 207 * average of the ratios of all possible single and double disk failures. 208 * 209 * In order to achieve a low imbalance ratio the number of permutations in 210 * the mapping must be significantly larger than the number of children. 211 * For dRAID the number of permutations has been limited to 512 to minimize 212 * the map size. This does result in a gradually increasing imbalance ratio 213 * as seen in the table below. Increasing the number of permutations for 214 * larger child counts would reduce the imbalance ratio. However, in practice 215 * when there are a large number of children each child is responsible for 216 * fewer total IOs so it's less of a concern. 217 * 218 * Note these values are hard coded and must never be changed. Existing 219 * pools depend on the same mapping always being generated in order to 220 * read and write from the correct locations. Any change would make 221 * existing pools completely inaccessible. 222 */ 223 static const draid_map_t draid_maps[VDEV_DRAID_MAX_MAPS] = { 224 { 2, 256, 0x89ef3dabbcc7de37, 0x00000000433d433d }, /* 1.000 */ 225 { 3, 256, 0x89a57f3de98121b4, 0x00000000bcd8b7b5 }, /* 1.000 */ 226 { 4, 256, 0xc9ea9ec82340c885, 0x00000001819d7c69 }, /* 1.000 */ 227 { 5, 256, 0xf46733b7f4d47dfd, 0x00000002a1648d74 }, /* 1.010 */ 228 { 6, 256, 0x88c3c62d8585b362, 0x00000003d3b0c2c4 }, /* 1.031 */ 229 { 7, 256, 0x3a65d809b4d1b9d5, 0x000000055c4183ee }, /* 1.043 */ 230 { 8, 256, 0xe98930e3c5d2e90a, 0x00000006edfb0329 }, /* 1.059 */ 231 { 9, 256, 0x5a5430036b982ccb, 0x00000008ceaf6934 }, /* 1.056 */ 232 { 10, 256, 0x92bf389e9eadac74, 0x0000000b26668c09 }, /* 1.072 */ 233 { 11, 256, 0x74ccebf1dcf3ae80, 0x0000000dd691358c }, /* 1.083 */ 234 { 12, 256, 0x8847e41a1a9f5671, 0x00000010a0c63c8e }, /* 1.097 */ 235 { 13, 256, 0x7481b56debf0e637, 0x0000001424121fe4 }, /* 1.100 */ 236 { 14, 256, 0x559b8c44065f8967, 0x00000016ab2ff079 }, /* 1.121 */ 237 { 15, 256, 0x34c49545a2ee7f01, 0x0000001a6028efd6 }, /* 1.103 */ 238 { 16, 256, 0xb85f4fa81a7698f7, 0x0000001e95ff5e66 }, /* 1.111 */ 239 { 17, 256, 0x6353e47b7e47aba0, 0x00000021a81fa0fe }, /* 1.133 */ 240 { 18, 256, 0xaa549746b1cbb81c, 0x00000026f02494c9 }, /* 1.131 */ 241 { 19, 256, 0x892e343f2f31d690, 0x00000029eb392835 }, /* 1.130 */ 242 { 20, 256, 0x76914824db98cc3f, 0x0000003004f31a7c }, /* 1.141 */ 243 { 21, 256, 0x4b3cbabf9cfb1d0f, 0x00000036363a2408 }, /* 1.139 */ 244 { 22, 256, 0xf45c77abb4f035d4, 0x00000038dd0f3e84 }, /* 1.150 */ 245 { 23, 256, 0x5e18bd7f3fd4baf4, 0x0000003f0660391f }, /* 1.174 */ 246 { 24, 256, 0xa7b3a4d285d6503b, 0x000000443dfc9ff6 }, /* 1.168 */ 247 { 25, 256, 0x56ac7dd967521f5a, 0x0000004b03a87eb7 }, /* 1.180 */ 248 { 26, 256, 0x3a42dfda4eb880f7, 0x000000522c719bba }, /* 1.226 */ 249 { 27, 256, 0xd200d2fc6b54bf60, 0x0000005760b4fdf5 }, /* 1.228 */ 250 { 28, 256, 0xc52605bbd486c546, 0x0000005e00d8f74c }, /* 1.217 */ 251 { 29, 256, 0xc761779e63cd762f, 0x00000067be3cd85c }, /* 1.239 */ 252 { 30, 256, 0xca577b1e07f85ca5, 0x0000006f5517f3e4 }, /* 1.238 */ 253 { 31, 256, 0xfd50a593c518b3d4, 0x0000007370e7778f }, /* 1.273 */ 254 { 32, 512, 0xc6c87ba5b042650b, 0x000000f7eb08a156 }, /* 1.191 */ 255 { 33, 512, 0xc3880d0c9d458304, 0x0000010734b5d160 }, /* 1.199 */ 256 { 34, 512, 0xe920927e4d8b2c97, 0x00000118c1edbce0 }, /* 1.195 */ 257 { 35, 512, 0x8da7fcda87bde316, 0x0000012a3e9f9110 }, /* 1.201 */ 258 { 36, 512, 0xcf09937491514a29, 0x0000013bd6a24bef }, /* 1.194 */ 259 { 37, 512, 0x9b5abbf345cbd7cc, 0x0000014b9d90fac3 }, /* 1.237 */ 260 { 38, 512, 0x506312a44668d6a9, 0x0000015e1b5f6148 }, /* 1.242 */ 261 { 39, 512, 0x71659ede62b4755f, 0x00000173ef029bcd }, /* 1.231 */ 262 { 40, 512, 0xa7fde73fb74cf2d7, 0x000001866fb72748 }, /* 1.233 */ 263 { 41, 512, 0x19e8b461a1dea1d3, 0x000001a046f76b23 }, /* 1.271 */ 264 { 42, 512, 0x031c9b868cc3e976, 0x000001afa64c49d3 }, /* 1.263 */ 265 { 43, 512, 0xbaa5125faa781854, 0x000001c76789e278 }, /* 1.270 */ 266 { 44, 512, 0x4ed55052550d721b, 0x000001d800ccd8eb }, /* 1.281 */ 267 { 45, 512, 0x0fd63ddbdff90677, 0x000001f08ad59ed2 }, /* 1.282 */ 268 { 46, 512, 0x36d66546de7fdd6f, 0x000002016f09574b }, /* 1.286 */ 269 { 47, 512, 0x99f997e7eafb69d7, 0x0000021e42e47cb6 }, /* 1.329 */ 270 { 48, 512, 0xbecd9c2571312c5d, 0x000002320fe2872b }, /* 1.286 */ 271 { 49, 512, 0xd97371329e488a32, 0x0000024cd73f2ca7 }, /* 1.322 */ 272 { 50, 512, 0x30e9b136670749ee, 0x000002681c83b0e0 }, /* 1.335 */ 273 { 51, 512, 0x11ad6bc8f47aaeb4, 0x0000027e9261b5d5 }, /* 1.305 */ 274 { 52, 512, 0x68e445300af432c1, 0x0000029aa0eb7dbf }, /* 1.330 */ 275 { 53, 512, 0x910fb561657ea98c, 0x000002b3dca04853 }, /* 1.365 */ 276 { 54, 512, 0xd619693d8ce5e7a5, 0x000002cc280e9c97 }, /* 1.334 */ 277 { 55, 512, 0x24e281f564dbb60a, 0x000002e9fa842713 }, /* 1.364 */ 278 { 56, 512, 0x947a7d3bdaab44c5, 0x000003046680f72e }, /* 1.374 */ 279 { 57, 512, 0x2d44fec9c093e0de, 0x00000324198ba810 }, /* 1.363 */ 280 { 58, 512, 0x87743c272d29bb4c, 0x0000033ec48c9ac9 }, /* 1.401 */ 281 { 59, 512, 0x96aa3b6f67f5d923, 0x0000034faead902c }, /* 1.392 */ 282 { 60, 512, 0x94a4f1faf520b0d3, 0x0000037d713ab005 }, /* 1.360 */ 283 { 61, 512, 0xb13ed3a272f711a2, 0x00000397368f3cbd }, /* 1.396 */ 284 { 62, 512, 0x3b1b11805fa4a64a, 0x000003b8a5e2840c }, /* 1.453 */ 285 { 63, 512, 0x4c74caad9172ba71, 0x000003d4be280290 }, /* 1.437 */ 286 { 64, 512, 0x035ff643923dd29e, 0x000003fad6c355e1 }, /* 1.402 */ 287 { 65, 512, 0x768e9171b11abd3c, 0x0000040eb07fed20 }, /* 1.459 */ 288 { 66, 512, 0x75880e6f78a13ddd, 0x000004433d6acf14 }, /* 1.423 */ 289 { 67, 512, 0x910b9714f698a877, 0x00000451ea65d5db }, /* 1.447 */ 290 { 68, 512, 0x87f5db6f9fdcf5c7, 0x000004732169e3f7 }, /* 1.450 */ 291 { 69, 512, 0x836d4968fbaa3706, 0x000004954068a380 }, /* 1.455 */ 292 { 70, 512, 0xc567d73a036421ab, 0x000004bd7cb7bd3d }, /* 1.463 */ 293 { 71, 512, 0x619df40f240b8fed, 0x000004e376c2e972 }, /* 1.463 */ 294 { 72, 512, 0x42763a680d5bed8e, 0x000005084275c680 }, /* 1.452 */ 295 { 73, 512, 0x5866f064b3230431, 0x0000052906f2c9ab }, /* 1.498 */ 296 { 74, 512, 0x9fa08548b1621a44, 0x0000054708019247 }, /* 1.526 */ 297 { 75, 512, 0xb6053078ce0fc303, 0x00000572cc5c72b0 }, /* 1.491 */ 298 { 76, 512, 0x4a7aad7bf3890923, 0x0000058e987bc8e9 }, /* 1.470 */ 299 { 77, 512, 0xe165613fd75b5a53, 0x000005c20473a211 }, /* 1.527 */ 300 { 78, 512, 0x3ff154ac878163a6, 0x000005d659194bf3 }, /* 1.509 */ 301 { 79, 512, 0x24b93ade0aa8a532, 0x0000060a201c4f8e }, /* 1.569 */ 302 { 80, 512, 0xc18e2d14cd9bb554, 0x0000062c55cfe48c }, /* 1.555 */ 303 { 81, 512, 0x98cc78302feb58b6, 0x0000066656a07194 }, /* 1.509 */ 304 { 82, 512, 0xc6c5fd5a2abc0543, 0x0000067cff94fbf8 }, /* 1.596 */ 305 { 83, 512, 0xa7962f514acbba21, 0x000006ab7b5afa2e }, /* 1.568 */ 306 { 84, 512, 0xba02545069ddc6dc, 0x000006d19861364f }, /* 1.541 */ 307 { 85, 512, 0x447c73192c35073e, 0x000006fce315ce35 }, /* 1.623 */ 308 { 86, 512, 0x48beef9e2d42b0c2, 0x00000720a8e38b6b }, /* 1.620 */ 309 { 87, 512, 0x4874cf98541a35e0, 0x00000758382a2273 }, /* 1.597 */ 310 { 88, 512, 0xad4cf8333a31127a, 0x00000781e1651b1b }, /* 1.575 */ 311 { 89, 512, 0x47ae4859d57888c1, 0x000007b27edbe5bc }, /* 1.627 */ 312 { 90, 512, 0x06f7723cfe5d1891, 0x000007dc2a96d8eb }, /* 1.596 */ 313 { 91, 512, 0xd4e44218d660576d, 0x0000080ac46f02d5 }, /* 1.622 */ 314 { 92, 512, 0x7066702b0d5be1f2, 0x00000832c96d154e }, /* 1.695 */ 315 { 93, 512, 0x011209b4f9e11fb9, 0x0000085eefda104c }, /* 1.605 */ 316 { 94, 512, 0x47ffba30a0b35708, 0x00000899badc32dc }, /* 1.625 */ 317 { 95, 512, 0x1a95a6ac4538aaa8, 0x000008b6b69a42b2 }, /* 1.687 */ 318 { 96, 512, 0xbda2b239bb2008eb, 0x000008f22d2de38a }, /* 1.621 */ 319 { 97, 512, 0x7ffa0bea90355c6c, 0x0000092e5b23b816 }, /* 1.699 */ 320 { 98, 512, 0x1d56ba34be426795, 0x0000094f482e5d1b }, /* 1.688 */ 321 { 99, 512, 0x0aa89d45c502e93d, 0x00000977d94a98ce }, /* 1.642 */ 322 { 100, 512, 0x54369449f6857774, 0x000009c06c9b34cc }, /* 1.683 */ 323 { 101, 512, 0xf7d4dd8445b46765, 0x000009e5dc542259 }, /* 1.755 */ 324 { 102, 512, 0xfa8866312f169469, 0x00000a16b54eae93 }, /* 1.692 */ 325 { 103, 512, 0xd8a5aea08aef3ff9, 0x00000a381d2cbfe7 }, /* 1.747 */ 326 { 104, 512, 0x66bcd2c3d5f9ef0e, 0x00000a8191817be7 }, /* 1.751 */ 327 { 105, 512, 0x3fb13a47a012ec81, 0x00000ab562b9a254 }, /* 1.751 */ 328 { 106, 512, 0x43100f01c9e5e3ca, 0x00000aeee84c185f }, /* 1.726 */ 329 { 107, 512, 0xca09c50ccee2d054, 0x00000b1c359c047d }, /* 1.788 */ 330 { 108, 512, 0xd7176732ac503f9b, 0x00000b578bc52a73 }, /* 1.740 */ 331 { 109, 512, 0xed206e51f8d9422d, 0x00000b8083e0d960 }, /* 1.780 */ 332 { 110, 512, 0x17ead5dc6ba0dcd6, 0x00000bcfb1a32ca8 }, /* 1.836 */ 333 { 111, 512, 0x5f1dc21e38a969eb, 0x00000c0171becdd6 }, /* 1.778 */ 334 { 112, 512, 0xddaa973de33ec528, 0x00000c3edaba4b95 }, /* 1.831 */ 335 { 113, 512, 0x2a5eccd7735a3630, 0x00000c630664e7df }, /* 1.825 */ 336 { 114, 512, 0xafcccee5c0b71446, 0x00000cb65392f6e4 }, /* 1.826 */ 337 { 115, 512, 0x8fa30c5e7b147e27, 0x00000cd4db391e55 }, /* 1.843 */ 338 { 116, 512, 0x5afe0711fdfafd82, 0x00000d08cb4ec35d }, /* 1.826 */ 339 { 117, 512, 0x533a6090238afd4c, 0x00000d336f115d1b }, /* 1.803 */ 340 { 118, 512, 0x90cf11b595e39a84, 0x00000d8e041c2048 }, /* 1.857 */ 341 { 119, 512, 0x0d61a3b809444009, 0x00000dcb798afe35 }, /* 1.877 */ 342 { 120, 512, 0x7f34da0f54b0d114, 0x00000df3922664e1 }, /* 1.849 */ 343 { 121, 512, 0xa52258d5b72f6551, 0x00000e4d37a9872d }, /* 1.867 */ 344 { 122, 512, 0xc1de54d7672878db, 0x00000e6583a94cf6 }, /* 1.978 */ 345 { 123, 512, 0x1d03354316a414ab, 0x00000ebffc50308d }, /* 1.947 */ 346 { 124, 512, 0xcebdcc377665412c, 0x00000edee1997cea }, /* 1.865 */ 347 { 125, 512, 0x4ddd4c04b1a12344, 0x00000f21d64b373f }, /* 1.881 */ 348 { 126, 512, 0x64fc8f94e3973658, 0x00000f8f87a8896b }, /* 1.882 */ 349 { 127, 512, 0x68765f78034a334e, 0x00000fb8fe62197e }, /* 1.867 */ 350 { 128, 512, 0xaf36b871a303e816, 0x00000fec6f3afb1e }, /* 1.972 */ 351 { 129, 512, 0x2a4cbf73866c3a28, 0x00001027febfe4e5 }, /* 1.896 */ 352 { 130, 512, 0x9cb128aacdcd3b2f, 0x0000106aa8ac569d }, /* 1.965 */ 353 { 131, 512, 0x5511d41c55869124, 0x000010bbd755ddf1 }, /* 1.963 */ 354 { 132, 512, 0x42f92461937f284a, 0x000010fb8bceb3b5 }, /* 1.925 */ 355 { 133, 512, 0xe2d89a1cf6f1f287, 0x0000114cf5331e34 }, /* 1.862 */ 356 { 134, 512, 0xdc631a038956200e, 0x0000116428d2adc5 }, /* 2.042 */ 357 { 135, 512, 0xb2e5ac222cd236be, 0x000011ca88e4d4d2 }, /* 1.935 */ 358 { 136, 512, 0xbc7d8236655d88e7, 0x000011e39cb94e66 }, /* 2.005 */ 359 { 137, 512, 0x073e02d88d2d8e75, 0x0000123136c7933c }, /* 2.041 */ 360 { 138, 512, 0x3ddb9c3873166be0, 0x00001280e4ec6d52 }, /* 1.997 */ 361 { 139, 512, 0x7d3b1a845420e1b5, 0x000012c2e7cd6a44 }, /* 1.996 */ 362 { 140, 512, 0x60102308aa7b2a6c, 0x000012fc490e6c7d }, /* 2.053 */ 363 { 141, 512, 0xdb22bb2f9eb894aa, 0x00001343f5a85a1a }, /* 1.971 */ 364 { 142, 512, 0xd853f879a13b1606, 0x000013bb7d5f9048 }, /* 2.018 */ 365 { 143, 512, 0x001620a03f804b1d, 0x000013e74cc794fd }, /* 1.961 */ 366 { 144, 512, 0xfdb52dda76fbf667, 0x00001442d2f22480 }, /* 2.046 */ 367 { 145, 512, 0xa9160110f66e24ff, 0x0000144b899f9dbb }, /* 1.968 */ 368 { 146, 512, 0x77306a30379ae03b, 0x000014cb98eb1f81 }, /* 2.143 */ 369 { 147, 512, 0x14f5985d2752319d, 0x000014feab821fc9 }, /* 2.064 */ 370 { 148, 512, 0xa4b8ff11de7863f8, 0x0000154a0e60b9c9 }, /* 2.023 */ 371 { 149, 512, 0x44b345426455c1b3, 0x000015999c3c569c }, /* 2.136 */ 372 { 150, 512, 0x272677826049b46c, 0x000015c9697f4b92 }, /* 2.063 */ 373 { 151, 512, 0x2f9216e2cd74fe40, 0x0000162b1f7bbd39 }, /* 1.974 */ 374 { 152, 512, 0x706ae3e763ad8771, 0x00001661371c55e1 }, /* 2.210 */ 375 { 153, 512, 0xf7fd345307c2480e, 0x000016e251f28b6a }, /* 2.006 */ 376 { 154, 512, 0x6e94e3d26b3139eb, 0x000016f2429bb8c6 }, /* 2.193 */ 377 { 155, 512, 0x5458bbfbb781fcba, 0x0000173efdeca1b9 }, /* 2.163 */ 378 { 156, 512, 0xa80e2afeccd93b33, 0x000017bfdcb78adc }, /* 2.046 */ 379 { 157, 512, 0x1e4ccbb22796cf9d, 0x00001826fdcc39c9 }, /* 2.084 */ 380 { 158, 512, 0x8fba4b676aaa3663, 0x00001841a1379480 }, /* 2.264 */ 381 { 159, 512, 0xf82b843814b315fa, 0x000018886e19b8a3 }, /* 2.074 */ 382 { 160, 512, 0x7f21e920ecf753a3, 0x0000191812ca0ea7 }, /* 2.282 */ 383 { 161, 512, 0x48bb8ea2c4caa620, 0x0000192f310faccf }, /* 2.148 */ 384 { 162, 512, 0x5cdb652b4952c91b, 0x0000199e1d7437c7 }, /* 2.355 */ 385 { 163, 512, 0x6ac1ba6f78c06cd4, 0x000019cd11f82c70 }, /* 2.164 */ 386 { 164, 512, 0x9faf5f9ca2669a56, 0x00001a18d5431f6a }, /* 2.393 */ 387 { 165, 512, 0xaa57e9383eb01194, 0x00001a9e7d253d85 }, /* 2.178 */ 388 { 166, 512, 0x896967bf495c34d2, 0x00001afb8319b9fc }, /* 2.334 */ 389 { 167, 512, 0xdfad5f05de225f1b, 0x00001b3a59c3093b }, /* 2.266 */ 390 { 168, 512, 0xfd299a99f9f2abdd, 0x00001bb6f1a10799 }, /* 2.304 */ 391 { 169, 512, 0xdda239e798fe9fd4, 0x00001bfae0c9692d }, /* 2.218 */ 392 { 170, 512, 0x5fca670414a32c3e, 0x00001c22129dbcff }, /* 2.377 */ 393 { 171, 512, 0x1bb8934314b087de, 0x00001c955db36cd0 }, /* 2.155 */ 394 { 172, 512, 0xd96394b4b082200d, 0x00001cfc8619b7e6 }, /* 2.404 */ 395 { 173, 512, 0xb612a7735b1c8cbc, 0x00001d303acdd585 }, /* 2.205 */ 396 { 174, 512, 0x28e7430fe5875fe1, 0x00001d7ed5b3697d }, /* 2.359 */ 397 { 175, 512, 0x5038e89efdd981b9, 0x00001dc40ec35c59 }, /* 2.158 */ 398 { 176, 512, 0x075fd78f1d14db7c, 0x00001e31c83b4a2b }, /* 2.614 */ 399 { 177, 512, 0xc50fafdb5021be15, 0x00001e7cdac82fbc }, /* 2.239 */ 400 { 178, 512, 0xe6dc7572ce7b91c7, 0x00001edd8bb454fc }, /* 2.493 */ 401 { 179, 512, 0x21f7843e7beda537, 0x00001f3a8e019d6c }, /* 2.327 */ 402 { 180, 512, 0xc83385e20b43ec82, 0x00001f70735ec137 }, /* 2.231 */ 403 { 181, 512, 0xca818217dddb21fd, 0x0000201ca44c5a3c }, /* 2.237 */ 404 { 182, 512, 0xe6035defea48f933, 0x00002038e3346658 }, /* 2.691 */ 405 { 183, 512, 0x47262a4f953dac5a, 0x000020c2e554314e }, /* 2.170 */ 406 { 184, 512, 0xe24c7246260873ea, 0x000021197e618d64 }, /* 2.600 */ 407 { 185, 512, 0xeef6b57c9b58e9e1, 0x0000217ea48ecddc }, /* 2.391 */ 408 { 186, 512, 0x2becd3346e386142, 0x000021c496d4a5f9 }, /* 2.677 */ 409 { 187, 512, 0x63c6207bdf3b40a3, 0x0000220e0f2eec0c }, /* 2.410 */ 410 { 188, 512, 0x3056ce8989767d4b, 0x0000228eb76cd137 }, /* 2.776 */ 411 { 189, 512, 0x91af61c307cee780, 0x000022e17e2ea501 }, /* 2.266 */ 412 { 190, 512, 0xda359da225f6d54f, 0x00002358a2debc19 }, /* 2.717 */ 413 { 191, 512, 0x0a5f7a2a55607ba0, 0x0000238a79dac18c }, /* 2.474 */ 414 { 192, 512, 0x27bb75bf5224638a, 0x00002403a58e2351 }, /* 2.673 */ 415 { 193, 512, 0x1ebfdb94630f5d0f, 0x00002492a10cb339 }, /* 2.420 */ 416 { 194, 512, 0x6eae5e51d9c5f6fb, 0x000024ce4bf98715 }, /* 2.898 */ 417 { 195, 512, 0x08d903b4daedc2e0, 0x0000250d1e15886c }, /* 2.363 */ 418 { 196, 512, 0xc722a2f7fa7cd686, 0x0000258a99ed0c9e }, /* 2.747 */ 419 { 197, 512, 0x8f71faf0e54e361d, 0x000025dee11976f5 }, /* 2.531 */ 420 { 198, 512, 0x87f64695c91a54e7, 0x0000264e00a43da0 }, /* 2.707 */ 421 { 199, 512, 0xc719cbac2c336b92, 0x000026d327277ac1 }, /* 2.315 */ 422 { 200, 512, 0xe7e647afaf771ade, 0x000027523a5c44bf }, /* 3.012 */ 423 { 201, 512, 0x12d4b5c38ce8c946, 0x0000273898432545 }, /* 2.378 */ 424 { 202, 512, 0xf2e0cd4067bdc94a, 0x000027e47bb2c935 }, /* 2.969 */ 425 { 203, 512, 0x21b79f14d6d947d3, 0x0000281e64977f0d }, /* 2.594 */ 426 { 204, 512, 0x515093f952f18cd6, 0x0000289691a473fd }, /* 2.763 */ 427 { 205, 512, 0xd47b160a1b1022c8, 0x00002903e8b52411 }, /* 2.457 */ 428 { 206, 512, 0xc02fc96684715a16, 0x0000297515608601 }, /* 3.057 */ 429 { 207, 512, 0xef51e68efba72ed0, 0x000029ef73604804 }, /* 2.590 */ 430 { 208, 512, 0x9e3be6e5448b4f33, 0x00002a2846ed074b }, /* 3.047 */ 431 { 209, 512, 0x81d446c6d5fec063, 0x00002a92ca693455 }, /* 2.676 */ 432 { 210, 512, 0xff215de8224e57d5, 0x00002b2271fe3729 }, /* 2.993 */ 433 { 211, 512, 0xe2524d9ba8f69796, 0x00002b64b99c3ba2 }, /* 2.457 */ 434 { 212, 512, 0xf6b28e26097b7e4b, 0x00002bd768b6e068 }, /* 3.182 */ 435 { 213, 512, 0x893a487f30ce1644, 0x00002c67f722b4b2 }, /* 2.563 */ 436 { 214, 512, 0x386566c3fc9871df, 0x00002cc1cf8b4037 }, /* 3.025 */ 437 { 215, 512, 0x1e0ed78edf1f558a, 0x00002d3948d36c7f }, /* 2.730 */ 438 { 216, 512, 0xe3bc20c31e61f113, 0x00002d6d6b12e025 }, /* 3.036 */ 439 { 217, 512, 0xd6c3ad2e23021882, 0x00002deff7572241 }, /* 2.722 */ 440 { 218, 512, 0xb4a9f95cf0f69c5a, 0x00002e67d537aa36 }, /* 3.356 */ 441 { 219, 512, 0x6e98ed6f6c38e82f, 0x00002e9720626789 }, /* 2.697 */ 442 { 220, 512, 0x2e01edba33fddac7, 0x00002f407c6b0198 }, /* 2.979 */ 443 { 221, 512, 0x559d02e1f5f57ccc, 0x00002fb6a5ab4f24 }, /* 2.858 */ 444 { 222, 512, 0xac18f5a916adcd8e, 0x0000304ae1c5c57e }, /* 3.258 */ 445 { 223, 512, 0x15789fbaddb86f4b, 0x0000306f6e019c78 }, /* 2.693 */ 446 { 224, 512, 0xf4a9c36d5bc4c408, 0x000030da40434213 }, /* 3.259 */ 447 { 225, 512, 0xf640f90fd2727f44, 0x00003189ed37b90c }, /* 2.733 */ 448 { 226, 512, 0xb5313d390d61884a, 0x000031e152616b37 }, /* 3.235 */ 449 { 227, 512, 0x4bae6b3ce9160939, 0x0000321f40aeac42 }, /* 2.983 */ 450 { 228, 512, 0x838c34480f1a66a1, 0x000032f389c0f78e }, /* 3.308 */ 451 { 229, 512, 0xb1c4a52c8e3d6060, 0x0000330062a40284 }, /* 2.715 */ 452 { 230, 512, 0xe0f1110c6d0ed822, 0x0000338be435644f }, /* 3.540 */ 453 { 231, 512, 0x9f1a8ccdcea68d4b, 0x000034045a4e97e1 }, /* 2.779 */ 454 { 232, 512, 0x3261ed62223f3099, 0x000034702cfc401c }, /* 3.084 */ 455 { 233, 512, 0xf2191e2311022d65, 0x00003509dd19c9fc }, /* 2.987 */ 456 { 234, 512, 0xf102a395c2033abc, 0x000035654dc96fae }, /* 3.341 */ 457 { 235, 512, 0x11fe378f027906b6, 0x000035b5193b0264 }, /* 2.793 */ 458 { 236, 512, 0xf777f2c026b337aa, 0x000036704f5d9297 }, /* 3.518 */ 459 { 237, 512, 0x1b04e9c2ee143f32, 0x000036dfbb7af218 }, /* 2.962 */ 460 { 238, 512, 0x2fcec95266f9352c, 0x00003785c8df24a9 }, /* 3.196 */ 461 { 239, 512, 0xfe2b0e47e427dd85, 0x000037cbdf5da729 }, /* 2.914 */ 462 { 240, 512, 0x72b49bf2225f6c6d, 0x0000382227c15855 }, /* 3.408 */ 463 { 241, 512, 0x50486b43df7df9c7, 0x0000389b88be6453 }, /* 2.903 */ 464 { 242, 512, 0x5192a3e53181c8ab, 0x000038ddf3d67263 }, /* 3.778 */ 465 { 243, 512, 0xe9f5d8365296fd5e, 0x0000399f1c6c9e9c }, /* 3.026 */ 466 { 244, 512, 0xc740263f0301efa8, 0x00003a147146512d }, /* 3.347 */ 467 { 245, 512, 0x23cd0f2b5671e67d, 0x00003ab10bcc0d9d }, /* 3.212 */ 468 { 246, 512, 0x002ccc7e5cd41390, 0x00003ad6cd14a6c0 }, /* 3.482 */ 469 { 247, 512, 0x9aafb3c02544b31b, 0x00003b8cb8779fb0 }, /* 3.146 */ 470 { 248, 512, 0x72ba07a78b121999, 0x00003c24142a5a3f }, /* 3.626 */ 471 { 249, 512, 0x3d784aa58edfc7b4, 0x00003cd084817d99 }, /* 2.952 */ 472 { 250, 512, 0xaab750424d8004af, 0x00003d506a8e098e }, /* 3.463 */ 473 { 251, 512, 0x84403fcf8e6b5ca2, 0x00003d4c54c2aec4 }, /* 3.131 */ 474 { 252, 512, 0x71eb7455ec98e207, 0x00003e655715cf2c }, /* 3.538 */ 475 { 253, 512, 0xd752b4f19301595b, 0x00003ecd7b2ca5ac }, /* 2.974 */ 476 { 254, 512, 0xc4674129750499de, 0x00003e99e86d3e95 }, /* 3.843 */ 477 { 255, 512, 0x9772baff5cd12ef5, 0x00003f895c019841 }, /* 3.088 */ 478 }; 479 480 /* 481 * Verify the map is valid. Each device index must appear exactly 482 * once in every row, and the permutation array checksum must match. 483 */ 484 static int 485 verify_perms(uint8_t *perms, uint64_t children, uint64_t nperms, 486 uint64_t checksum) 487 { 488 int countssz = sizeof (uint16_t) * children; 489 uint16_t *counts = kmem_zalloc(countssz, KM_SLEEP); 490 491 for (int i = 0; i < nperms; i++) { 492 for (int j = 0; j < children; j++) { 493 uint8_t val = perms[(i * children) + j]; 494 495 if (val >= children || counts[val] != i) { 496 kmem_free(counts, countssz); 497 return (EINVAL); 498 } 499 500 counts[val]++; 501 } 502 } 503 504 if (checksum != 0) { 505 int permssz = sizeof (uint8_t) * children * nperms; 506 zio_cksum_t cksum; 507 508 fletcher_4_native_varsize(perms, permssz, &cksum); 509 510 if (checksum != cksum.zc_word[0]) { 511 kmem_free(counts, countssz); 512 return (ECKSUM); 513 } 514 } 515 516 kmem_free(counts, countssz); 517 518 return (0); 519 } 520 521 /* 522 * Generate the permutation array for the draid_map_t. These maps control 523 * the placement of all data in a dRAID. Therefore it's critical that the 524 * seed always generates the same mapping. We provide our own pseudo-random 525 * number generator for this purpose. 526 */ 527 int 528 vdev_draid_generate_perms(const draid_map_t *map, uint8_t **permsp) 529 { 530 VERIFY3U(map->dm_children, >=, VDEV_DRAID_MIN_CHILDREN); 531 VERIFY3U(map->dm_children, <=, VDEV_DRAID_MAX_CHILDREN); 532 VERIFY3U(map->dm_seed, !=, 0); 533 VERIFY3U(map->dm_nperms, !=, 0); 534 VERIFY0P(map->dm_perms); 535 536 #ifdef _KERNEL 537 /* 538 * The kernel code always provides both a map_seed and checksum. 539 * Only the tests/zfs-tests/cmd/draid/draid.c utility will provide 540 * a zero checksum when generating new candidate maps. 541 */ 542 VERIFY3U(map->dm_checksum, !=, 0); 543 #endif 544 uint64_t children = map->dm_children; 545 uint64_t nperms = map->dm_nperms; 546 int rowsz = sizeof (uint8_t) * children; 547 int permssz = rowsz * nperms; 548 uint8_t *perms; 549 550 /* Allocate the permutation array */ 551 perms = vmem_alloc(permssz, KM_SLEEP); 552 553 /* Setup an initial row with a known pattern */ 554 uint8_t *initial_row = kmem_alloc(rowsz, KM_SLEEP); 555 for (int i = 0; i < children; i++) 556 initial_row[i] = i; 557 558 uint64_t draid_seed[2] = { VDEV_DRAID_SEED, map->dm_seed }; 559 uint8_t *current_row, *previous_row = initial_row; 560 561 /* 562 * Perform a Fisher-Yates shuffle of each row using the previous 563 * row as the starting point. An initial_row with known pattern 564 * is used as the input for the first row. 565 */ 566 for (int i = 0; i < nperms; i++) { 567 current_row = &perms[i * children]; 568 memcpy(current_row, previous_row, rowsz); 569 570 for (int j = children - 1; j > 0; j--) { 571 uint64_t k = vdev_draid_rand(draid_seed) % (j + 1); 572 uint8_t val = current_row[j]; 573 current_row[j] = current_row[k]; 574 current_row[k] = val; 575 } 576 577 previous_row = current_row; 578 } 579 580 kmem_free(initial_row, rowsz); 581 582 int error = verify_perms(perms, children, nperms, map->dm_checksum); 583 if (error) { 584 vmem_free(perms, permssz); 585 return (error); 586 } 587 588 *permsp = perms; 589 590 return (0); 591 } 592 593 static void 594 vdev_draid_swap_perms(uint8_t *perms, uint64_t i, uint64_t j) 595 { 596 uint8_t val = perms[i]; 597 598 perms[i] = perms[j]; 599 perms[j] = val; 600 } 601 602 /* 603 * Shuffle every i-th disk in slices that lie alongside in the big width row, 604 * increasing disk indices in each next slice in the row accordingly. The 605 * input to this function is the array of ready permutations from 606 * vdev_draid_generate_perms(), so in order to correctly shuffle i-th disks, 607 * we need to locate their position first and build a map of their locations. 608 * 609 * Note: the same Fisher-Yates shuffle algorithm is used as in 610 * vdev_draid_generate_perms(). 611 */ 612 static void 613 vdev_draid_shuffle_perms(const draid_map_t *map, uint8_t *perms, uint64_t width) 614 { 615 uint64_t cn = map->dm_children; 616 uint64_t n = width / cn; 617 uint64_t nperms = map->dm_nperms / n * n; 618 619 if (width <= cn) 620 return; 621 622 VERIFY3U(width, >=, VDEV_DRAID_MIN_CHILDREN); 623 VERIFY3U(width, <=, VDEV_DRAID_MAX_CHILDREN); 624 ASSERT0(width % cn); 625 626 uint64_t draid_seed[2] = { VDEV_DRAID_SEED, map->dm_seed }; 627 628 uint8_t *cmap = kmem_alloc(n, KM_SLEEP); 629 630 for (int i = 0; i < nperms; i += n) { 631 for (int j = 0; j < cn; j++) { 632 633 /* locate position of the same child in other slices */ 634 for (int k = n - 1; k > 0; k--) 635 for (int l = 0; l < cn; l++) 636 if (perms[(i+k) * cn + l] == 637 perms[(i+0) * cn + j]) 638 cmap[k] = l; 639 cmap[0] = j; 640 641 /* increase index values for slices on the right */ 642 for (int k = n - 1; k > 0; k--) 643 perms[(i+k) * cn + cmap[k]] += k * cn; 644 645 /* shuffle */ 646 for (int k = n - 1; k > 0; k--) { 647 int l = vdev_draid_rand(draid_seed) % (k + 1); 648 if (k == l) 649 continue; 650 vdev_draid_swap_perms(perms, 651 (i+k) * cn + cmap[k], 652 (i+l) * cn + cmap[l]); 653 } 654 } 655 } 656 657 kmem_free(cmap, n); 658 } 659 660 /* 661 * Lookup the fixed draid_map_t for the requested number of children. 662 */ 663 int 664 vdev_draid_lookup_map(uint64_t children, const draid_map_t **mapp) 665 { 666 for (int i = 0; i < VDEV_DRAID_MAX_MAPS; i++) { 667 if (draid_maps[i].dm_children == children) { 668 *mapp = &draid_maps[i]; 669 return (0); 670 } 671 } 672 673 return (ENOENT); 674 } 675 676 /* 677 * Lookup the permutation array and iteration id for the provided offset. 678 */ 679 static void 680 vdev_draid_get_perm(vdev_draid_config_t *vdc, uint64_t pindex, 681 uint8_t **base, uint64_t *iter) 682 { 683 uint64_t n = vdc->vdc_width / vdc->vdc_children; 684 uint64_t ncols = vdc->vdc_children; 685 uint64_t nperms = (vdc->vdc_nperms / n) * n; 686 uint64_t poff = pindex % (nperms * ncols); 687 688 ASSERT3P(nperms, >=, ncols * n); 689 690 *base = vdc->vdc_perms + (poff / (ncols * n)) * (ncols * n); 691 *iter = (poff % ncols) + (pindex % n) * ncols; 692 } 693 694 static inline uint64_t 695 vdev_draid_permute_id(vdev_draid_config_t *vdc, 696 uint8_t *base, uint64_t iter, uint64_t index) 697 { 698 if (vdc->vdc_width > vdc->vdc_children) { 699 uint64_t off = (iter / vdc->vdc_children) * vdc->vdc_children; 700 return (base[(index + iter) % vdc->vdc_children + off]); 701 } 702 703 return ((base[index] + iter) % vdc->vdc_children); 704 } 705 706 /* 707 * Return the asize which is the psize rounded up to a full group width. 708 * i.e. vdev_draid_psize_to_asize(). 709 */ 710 static uint64_t 711 vdev_draid_psize_to_asize(vdev_t *vd, uint64_t psize, uint64_t txg) 712 { 713 (void) txg; 714 vdev_draid_config_t *vdc = vd->vdev_tsd; 715 uint64_t ashift = vd->vdev_ashift; 716 717 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 718 719 uint64_t rows = ((psize - 1) / (vdc->vdc_ndata << ashift)) + 1; 720 uint64_t asize = (rows * vdc->vdc_groupwidth) << ashift; 721 722 ASSERT3U(asize, !=, 0); 723 ASSERT0(asize % (vdc->vdc_groupwidth)); 724 725 return (asize); 726 } 727 728 /* 729 * Deflate the asize to the psize, this includes stripping parity. 730 */ 731 uint64_t 732 vdev_draid_asize_to_psize(vdev_t *vd, uint64_t asize, uint64_t txg) 733 { 734 (void) txg; 735 vdev_draid_config_t *vdc = vd->vdev_tsd; 736 737 ASSERT0(asize % vdc->vdc_groupwidth); 738 739 return ((asize / vdc->vdc_groupwidth) * vdc->vdc_ndata); 740 } 741 742 /* 743 * Convert a logical offset to the corresponding group number. 744 */ 745 static uint64_t 746 vdev_draid_offset_to_group(vdev_t *vd, uint64_t offset) 747 { 748 vdev_draid_config_t *vdc = vd->vdev_tsd; 749 750 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 751 752 return (offset / vdc->vdc_groupsz); 753 } 754 755 /* 756 * Convert a group number to the logical starting offset for that group. 757 */ 758 static uint64_t 759 vdev_draid_group_to_offset(vdev_t *vd, uint64_t group) 760 { 761 vdev_draid_config_t *vdc = vd->vdev_tsd; 762 763 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 764 765 return (group * vdc->vdc_groupsz); 766 } 767 768 /* 769 * Full stripe writes. When writing, all columns (D+P) are required. Parity 770 * is calculated over all the columns, including empty zero filled sectors, 771 * and each is written to disk. While only the data columns are needed for 772 * a normal read, all of the columns are required for reconstruction when 773 * performing a sequential resilver. 774 * 775 * For "big columns" it's sufficient to map the correct range of the zio ABD. 776 * Partial columns require allocating a gang ABD in order to zero fill the 777 * empty sectors. When the column is empty a zero filled sector must be 778 * mapped. In all cases the data ABDs must be the same size as the parity 779 * ABDs (e.g. rc->rc_size == parity_size). 780 */ 781 static void 782 vdev_draid_map_alloc_write(zio_t *zio, uint64_t abd_offset, raidz_row_t *rr) 783 { 784 uint64_t skip_size = 1ULL << zio->io_vd->vdev_top->vdev_ashift; 785 uint64_t parity_size = rr->rr_col[0].rc_size; 786 uint64_t abd_off = abd_offset; 787 788 ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE); 789 ASSERT3U(parity_size, ==, abd_get_size(rr->rr_col[0].rc_abd)); 790 791 for (uint64_t c = rr->rr_firstdatacol; c < rr->rr_cols; c++) { 792 raidz_col_t *rc = &rr->rr_col[c]; 793 794 if (rc->rc_size == 0) { 795 /* empty data column (small write), add a skip sector */ 796 ASSERT3U(skip_size, ==, parity_size); 797 rc->rc_abd = abd_get_zeros(skip_size); 798 } else if (rc->rc_size == parity_size) { 799 /* this is a "big column" */ 800 rc->rc_abd = abd_get_offset_struct(&rc->rc_abdstruct, 801 zio->io_abd, abd_off, rc->rc_size); 802 } else { 803 /* short data column, add a skip sector */ 804 ASSERT3U(rc->rc_size + skip_size, ==, parity_size); 805 rc->rc_abd = abd_alloc_gang(); 806 abd_gang_add(rc->rc_abd, abd_get_offset_size( 807 zio->io_abd, abd_off, rc->rc_size), B_TRUE); 808 abd_gang_add(rc->rc_abd, abd_get_zeros(skip_size), 809 B_TRUE); 810 } 811 812 ASSERT3U(abd_get_size(rc->rc_abd), ==, parity_size); 813 814 abd_off += rc->rc_size; 815 rc->rc_size = parity_size; 816 } 817 818 IMPLY(abd_offset != 0, abd_off == zio->io_size); 819 } 820 821 /* 822 * Scrub/resilver reads. In order to store the contents of the skip sectors 823 * an additional ABD is allocated. The columns are handled in the same way 824 * as a full stripe write except instead of using the zero ABD the newly 825 * allocated skip ABD is used to back the skip sectors. In all cases the 826 * data ABD must be the same size as the parity ABDs. 827 */ 828 static void 829 vdev_draid_map_alloc_scrub(zio_t *zio, uint64_t abd_offset, raidz_row_t *rr) 830 { 831 uint64_t skip_size = 1ULL << zio->io_vd->vdev_top->vdev_ashift; 832 uint64_t parity_size = rr->rr_col[0].rc_size; 833 uint64_t abd_off = abd_offset; 834 uint64_t skip_off = 0; 835 836 ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); 837 ASSERT0P(rr->rr_abd_empty); 838 839 if (rr->rr_nempty > 0) { 840 rr->rr_abd_empty = abd_alloc_linear(rr->rr_nempty * skip_size, 841 B_FALSE); 842 } 843 844 for (uint64_t c = rr->rr_firstdatacol; c < rr->rr_cols; c++) { 845 raidz_col_t *rc = &rr->rr_col[c]; 846 847 if (rc->rc_size == 0) { 848 /* empty data column (small read), add a skip sector */ 849 ASSERT3U(skip_size, ==, parity_size); 850 ASSERT3U(rr->rr_nempty, !=, 0); 851 rc->rc_abd = abd_get_offset_size(rr->rr_abd_empty, 852 skip_off, skip_size); 853 skip_off += skip_size; 854 } else if (rc->rc_size == parity_size) { 855 /* this is a "big column" */ 856 rc->rc_abd = abd_get_offset_struct(&rc->rc_abdstruct, 857 zio->io_abd, abd_off, rc->rc_size); 858 } else { 859 /* short data column, add a skip sector */ 860 ASSERT3U(rc->rc_size + skip_size, ==, parity_size); 861 ASSERT3U(rr->rr_nempty, !=, 0); 862 rc->rc_abd = abd_alloc_gang(); 863 abd_gang_add(rc->rc_abd, abd_get_offset_size( 864 zio->io_abd, abd_off, rc->rc_size), B_TRUE); 865 abd_gang_add(rc->rc_abd, abd_get_offset_size( 866 rr->rr_abd_empty, skip_off, skip_size), B_TRUE); 867 skip_off += skip_size; 868 } 869 870 uint64_t abd_size = abd_get_size(rc->rc_abd); 871 ASSERT3U(abd_size, ==, abd_get_size(rr->rr_col[0].rc_abd)); 872 873 /* 874 * Increase rc_size so the skip ABD is included in subsequent 875 * parity calculations. 876 */ 877 abd_off += rc->rc_size; 878 rc->rc_size = abd_size; 879 } 880 881 IMPLY(abd_offset != 0, abd_off == zio->io_size); 882 ASSERT3U(skip_off, ==, rr->rr_nempty * skip_size); 883 } 884 885 /* 886 * Normal reads. In this common case only the columns containing data 887 * are read in to the zio ABDs. Neither the parity columns or empty skip 888 * sectors are read unless the checksum fails verification. In which case 889 * vdev_raidz_read_all() will call vdev_draid_map_alloc_empty() to expand 890 * the raid map in order to allow reconstruction using the parity data and 891 * skip sectors. 892 */ 893 static void 894 vdev_draid_map_alloc_read(zio_t *zio, uint64_t abd_offset, raidz_row_t *rr) 895 { 896 uint64_t abd_off = abd_offset; 897 898 ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); 899 900 for (uint64_t c = rr->rr_firstdatacol; c < rr->rr_cols; c++) { 901 raidz_col_t *rc = &rr->rr_col[c]; 902 903 if (rc->rc_size > 0) { 904 rc->rc_abd = abd_get_offset_struct(&rc->rc_abdstruct, 905 zio->io_abd, abd_off, rc->rc_size); 906 abd_off += rc->rc_size; 907 } 908 } 909 910 IMPLY(abd_offset != 0, abd_off == zio->io_size); 911 } 912 913 /* 914 * Converts a normal "read" raidz_row_t to a "scrub" raidz_row_t. The key 915 * difference is that an ABD is allocated to back skip sectors so they may 916 * be read in to memory, verified, and repaired if needed. 917 */ 918 void 919 vdev_draid_map_alloc_empty(zio_t *zio, raidz_row_t *rr) 920 { 921 uint64_t skip_size = 1ULL << zio->io_vd->vdev_top->vdev_ashift; 922 uint64_t parity_size = rr->rr_col[0].rc_size; 923 uint64_t skip_off = 0; 924 925 ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); 926 ASSERT0P(rr->rr_abd_empty); 927 928 if (rr->rr_nempty > 0) { 929 rr->rr_abd_empty = abd_alloc_linear(rr->rr_nempty * skip_size, 930 B_FALSE); 931 } 932 933 for (uint64_t c = rr->rr_firstdatacol; c < rr->rr_cols; c++) { 934 raidz_col_t *rc = &rr->rr_col[c]; 935 936 if (rc->rc_size == 0) { 937 /* empty data column (small read), add a skip sector */ 938 ASSERT3U(skip_size, ==, parity_size); 939 ASSERT3U(rr->rr_nempty, !=, 0); 940 ASSERT0P(rc->rc_abd); 941 rc->rc_abd = abd_get_offset_size(rr->rr_abd_empty, 942 skip_off, skip_size); 943 skip_off += skip_size; 944 } else if (rc->rc_size == parity_size) { 945 /* this is a "big column", nothing to add */ 946 ASSERT3P(rc->rc_abd, !=, NULL); 947 } else { 948 /* 949 * short data column, add a skip sector and clear 950 * rc_tried to force the entire column to be re-read 951 * thereby including the missing skip sector data 952 * which is needed for reconstruction. 953 */ 954 ASSERT3U(rc->rc_size + skip_size, ==, parity_size); 955 ASSERT3U(rr->rr_nempty, !=, 0); 956 ASSERT3P(rc->rc_abd, !=, NULL); 957 ASSERT(!abd_is_gang(rc->rc_abd)); 958 abd_t *read_abd = rc->rc_abd; 959 rc->rc_abd = abd_alloc_gang(); 960 abd_gang_add(rc->rc_abd, read_abd, B_TRUE); 961 abd_gang_add(rc->rc_abd, abd_get_offset_size( 962 rr->rr_abd_empty, skip_off, skip_size), B_TRUE); 963 skip_off += skip_size; 964 rc->rc_tried = 0; 965 } 966 967 /* 968 * Increase rc_size so the empty ABD is included in subsequent 969 * parity calculations. 970 */ 971 rc->rc_size = parity_size; 972 } 973 974 ASSERT3U(skip_off, ==, rr->rr_nempty * skip_size); 975 } 976 977 /* 978 * Verify that all empty sectors are zero filled before using them to 979 * calculate parity. Otherwise, silent corruption in an empty sector will 980 * result in bad parity being generated. That bad parity will then be 981 * considered authoritative and overwrite the good parity on disk. This 982 * is possible because the checksum is only calculated over the data, 983 * thus it cannot be used to detect damage in empty sectors. 984 */ 985 int 986 vdev_draid_map_verify_empty(zio_t *zio, raidz_row_t *rr) 987 { 988 uint64_t skip_size = 1ULL << zio->io_vd->vdev_top->vdev_ashift; 989 uint64_t parity_size = rr->rr_col[0].rc_size; 990 uint64_t skip_off = parity_size - skip_size; 991 uint64_t empty_off = 0; 992 int ret = 0; 993 994 ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); 995 ASSERT3P(rr->rr_abd_empty, !=, NULL); 996 ASSERT3U(rr->rr_bigcols, >, 0); 997 998 void *zero_buf = kmem_zalloc(skip_size, KM_SLEEP); 999 1000 for (int c = rr->rr_bigcols; c < rr->rr_cols; c++) { 1001 raidz_col_t *rc = &rr->rr_col[c]; 1002 1003 ASSERT3P(rc->rc_abd, !=, NULL); 1004 ASSERT3U(rc->rc_size, ==, parity_size); 1005 1006 if (abd_cmp_buf_off(rc->rc_abd, zero_buf, skip_off, 1007 skip_size) != 0) { 1008 vdev_raidz_checksum_error(zio, rc, rc->rc_abd); 1009 abd_zero_off(rc->rc_abd, skip_off, skip_size); 1010 rc->rc_error = SET_ERROR(ECKSUM); 1011 ret++; 1012 } 1013 1014 empty_off += skip_size; 1015 } 1016 1017 ASSERT3U(empty_off, ==, abd_get_size(rr->rr_abd_empty)); 1018 1019 kmem_free(zero_buf, skip_size); 1020 1021 return (ret); 1022 } 1023 1024 /* 1025 * Given a logical address within a dRAID configuration, return the physical 1026 * address on the first drive in the group that this address maps to 1027 * (at position 'start' in permutation number 'perm'). 1028 */ 1029 static uint64_t 1030 vdev_draid_logical_to_physical(vdev_t *vd, uint64_t logical_offset, 1031 uint64_t *perm, uint64_t *start, uint64_t *ndisks) 1032 { 1033 vdev_draid_config_t *vdc = vd->vdev_tsd; 1034 1035 /* b is the dRAID (parent) sector offset. */ 1036 uint64_t ashift = vd->vdev_top->vdev_ashift; 1037 uint64_t b_offset = logical_offset >> ashift; 1038 1039 /* 1040 * The height of a row in units of the vdev's minimum sector size. 1041 * This is the amount of data written to each disk of each group 1042 * in a given permutation. 1043 */ 1044 uint64_t rowheight_sectors = VDEV_DRAID_ROWHEIGHT >> ashift; 1045 1046 /* 1047 * We cycle through a disk permutation every groupsz * ngroups chunk 1048 * of address space. Note that ngroups * groupsz must be a multiple 1049 * of the number of data drives (ndisks) in order to guarantee 1050 * alignment. So, for example, if our row height is 16MB, our group 1051 * size is 10, and there are 13 data drives in the draid, then ngroups 1052 * will be 13, we will change permutation every 2.08GB and each 1053 * disk will have 160MB of data per chunk. 1054 */ 1055 uint64_t groupwidth = vdc->vdc_groupwidth; 1056 uint64_t ngroups = vdc->vdc_ngroups; 1057 1058 uint64_t group = logical_offset / vdc->vdc_groupsz; 1059 uint64_t fgrps = vdc->vdc_width / vdc->vdc_children; 1060 1061 *perm = (group / ngroups) * fgrps; 1062 1063 /* 1064 * Failure groups starting from (vdc_nspares % fgrps) have one less 1065 * spare, so they have one more ndisks. 1066 */ 1067 uint64_t biggies = vdc->vdc_nspares % fgrps; 1068 1069 uint64_t poff = 0; 1070 group %= ngroups; 1071 uint64_t ngroups1 = ngroups / fgrps; 1072 if (!biggies || group < biggies * ngroups1) 1073 poff = group / ngroups1; 1074 else 1075 poff = biggies + 1076 (group - (biggies * ngroups1)) / (ngroups1 + 1); 1077 ASSERT3U(poff, <, fgrps); 1078 *perm += poff; 1079 1080 *ndisks = (vdc->vdc_ndisks / fgrps) + 1081 (biggies ? ((poff >= biggies) ? 1 : 0) : 0); 1082 1083 /* b_offset is the sector offset within a group chunk */ 1084 b_offset = b_offset % (rowheight_sectors * groupwidth); 1085 ASSERT0(b_offset % groupwidth); 1086 1087 /* 1088 * Find the starting byte offset on each child vdev: 1089 * - within a permutation there are ngroups groups spread over the 1090 * rows, where each row covers a slice portion of the disk 1091 * - each permutation has (groupwidth * ngroups) / ndisks rows 1092 * - so each permutation covers rows * slice portion of the disk 1093 * - so we need to find the row where this IO group target begins 1094 */ 1095 uint64_t perm_rows = (groupwidth * ngroups) / vdc->vdc_ndisks; 1096 1097 /* Adjust group for our failure group. */ 1098 if (!biggies || poff <= biggies) 1099 group -= poff * ngroups1; 1100 else 1101 group -= (biggies * ngroups1) + 1102 (poff - biggies) * (ngroups1 + 1); 1103 1104 IMPLY(poff < biggies, group < ngroups1); 1105 ASSERT3U(group, <=, ngroups1); 1106 1107 /* 1108 * groupstart is where the group this IO will land in "starts" in 1109 * the permutation array. 1110 */ 1111 uint64_t groupstart = (group * groupwidth) % *ndisks; 1112 ASSERT3U(groupstart + groupwidth, <=, *ndisks + groupstart); 1113 *start = groupstart; 1114 1115 /* Adjust ngroups for our failure group. */ 1116 ngroups = ngroups1 + ((biggies && poff >= biggies) ? 1 : 0); 1117 1118 ASSERT3U(group, <, ngroups); 1119 1120 uint64_t row = ((*perm / fgrps) * perm_rows) + 1121 (((group % ngroups) * groupwidth) / *ndisks); 1122 1123 return (((rowheight_sectors * row) + 1124 (b_offset / groupwidth)) << ashift); 1125 } 1126 1127 static uint64_t 1128 vdev_draid_map_alloc_row(zio_t *zio, raidz_row_t **rrp, uint64_t io_offset, 1129 uint64_t abd_offset, uint64_t abd_size) 1130 { 1131 vdev_t *vd = zio->io_vd; 1132 vdev_draid_config_t *vdc = vd->vdev_tsd; 1133 uint64_t ashift = vd->vdev_top->vdev_ashift; 1134 uint64_t io_size = abd_size; 1135 uint64_t io_asize = vdev_draid_psize_to_asize(vd, io_size, 0); 1136 uint64_t group = vdev_draid_offset_to_group(vd, io_offset); 1137 uint64_t start_offset = vdev_draid_group_to_offset(vd, group + 1); 1138 1139 /* 1140 * Limit the io_size to the space remaining in the group. A second 1141 * row in the raidz_map_t is created for the remainder. 1142 */ 1143 if (io_offset + io_asize > start_offset) { 1144 io_size = vdev_draid_asize_to_psize(vd, 1145 start_offset - io_offset, 0); 1146 } 1147 1148 /* 1149 * At most a block may span the logical end of one group and the start 1150 * of the next group. Therefore, at the end of a group the io_size must 1151 * span the group width evenly and the remainder must be aligned to the 1152 * start of the next group. 1153 */ 1154 IMPLY(abd_offset == 0 && io_size < zio->io_size, 1155 (io_asize >> ashift) % vdc->vdc_groupwidth == 0); 1156 IMPLY(abd_offset != 0, 1157 vdev_draid_group_to_offset(vd, group) == io_offset); 1158 1159 /* Lookup starting byte offset on each child vdev */ 1160 uint64_t groupstart, perm, ndisks; 1161 uint64_t physical_offset = vdev_draid_logical_to_physical(vd, 1162 io_offset, &perm, &groupstart, &ndisks); 1163 1164 /* 1165 * If there is less than groupwidth drives available after the group 1166 * start, the group is going to wrap onto the next row. 'wrap' is the 1167 * group disk number that starts on the next row. 1168 */ 1169 uint64_t groupwidth = vdc->vdc_groupwidth; 1170 uint64_t wrap = groupwidth; 1171 1172 if (groupstart + groupwidth > ndisks) 1173 wrap = ndisks - groupstart; 1174 1175 /* The io size in units of the vdev's minimum sector size. */ 1176 const uint64_t psize = io_size >> ashift; 1177 1178 /* 1179 * "Quotient": The number of data sectors for this stripe on all but 1180 * the "big column" child vdevs that also contain "remainder" data. 1181 */ 1182 uint64_t q = psize / vdc->vdc_ndata; 1183 1184 /* 1185 * "Remainder": The number of partial stripe data sectors in this I/O. 1186 * This will add a sector to some, but not all, child vdevs. 1187 */ 1188 uint64_t r = psize - q * vdc->vdc_ndata; 1189 1190 /* The number of "big columns" - those which contain remainder data. */ 1191 uint64_t bc = (r == 0 ? 0 : r + vdc->vdc_nparity); 1192 ASSERT3U(bc, <, groupwidth); 1193 1194 /* The total number of data and parity sectors for this I/O. */ 1195 uint64_t tot = psize + (vdc->vdc_nparity * (q + (r == 0 ? 0 : 1))); 1196 1197 ASSERT3U(vdc->vdc_nparity, >, 0); 1198 1199 raidz_row_t *rr = vdev_raidz_row_alloc(groupwidth, zio); 1200 rr->rr_bigcols = bc; 1201 rr->rr_firstdatacol = vdc->vdc_nparity; 1202 #ifdef ZFS_DEBUG 1203 rr->rr_offset = io_offset; 1204 rr->rr_size = io_size; 1205 #endif 1206 *rrp = rr; 1207 1208 uint8_t *base; 1209 uint64_t iter, asize = 0; 1210 vdev_draid_get_perm(vdc, perm, &base, &iter); 1211 for (uint64_t i = 0; i < groupwidth; i++) { 1212 raidz_col_t *rc = &rr->rr_col[i]; 1213 uint64_t c = (groupstart + i) % ndisks; 1214 1215 /* increment the offset if we wrap to the next row */ 1216 if (i == wrap) 1217 physical_offset += VDEV_DRAID_ROWHEIGHT; 1218 1219 rc->rc_devidx = vdev_draid_permute_id(vdc, base, iter, c); 1220 rc->rc_offset = physical_offset; 1221 1222 if (q == 0 && i >= bc) 1223 rc->rc_size = 0; 1224 else if (i < bc) 1225 rc->rc_size = (q + 1) << ashift; 1226 else 1227 rc->rc_size = q << ashift; 1228 1229 asize += rc->rc_size; 1230 } 1231 1232 ASSERT3U(asize, ==, tot << ashift); 1233 rr->rr_nempty = roundup(tot, groupwidth) - tot; 1234 IMPLY(bc > 0, rr->rr_nempty == groupwidth - bc); 1235 1236 /* Allocate buffers for the parity columns */ 1237 for (uint64_t c = 0; c < rr->rr_firstdatacol; c++) { 1238 raidz_col_t *rc = &rr->rr_col[c]; 1239 rc->rc_abd = abd_alloc_linear(rc->rc_size, B_FALSE); 1240 } 1241 1242 /* 1243 * Map buffers for data columns and allocate/map buffers for skip 1244 * sectors. There are three distinct cases for dRAID which are 1245 * required to support sequential rebuild. 1246 */ 1247 if (zio->io_type == ZIO_TYPE_WRITE) { 1248 vdev_draid_map_alloc_write(zio, abd_offset, rr); 1249 } else if ((rr->rr_nempty > 0) && 1250 (zio->io_flags & (ZIO_FLAG_SCRUB | ZIO_FLAG_RESILVER))) { 1251 vdev_draid_map_alloc_scrub(zio, abd_offset, rr); 1252 } else { 1253 ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); 1254 vdev_draid_map_alloc_read(zio, abd_offset, rr); 1255 } 1256 1257 return (io_size); 1258 } 1259 1260 /* 1261 * Allocate the raidz mapping to be applied to the dRAID I/O. The parity 1262 * calculations for dRAID are identical to raidz however there are a few 1263 * differences in the layout. 1264 * 1265 * - dRAID always allocates a full stripe width. Any extra sectors due 1266 * this padding are zero filled and written to disk. They will be read 1267 * back during a scrub or repair operation since they are included in 1268 * the parity calculation. This property enables sequential resilvering. 1269 * 1270 * - When the block at the logical offset spans redundancy groups then two 1271 * rows are allocated in the raidz_map_t. One row resides at the end of 1272 * the first group and the other at the start of the following group. 1273 */ 1274 static raidz_map_t * 1275 vdev_draid_map_alloc(zio_t *zio) 1276 { 1277 raidz_row_t *rr[2]; 1278 uint64_t abd_offset = 0; 1279 uint64_t abd_size = zio->io_size; 1280 uint64_t io_offset = zio->io_offset; 1281 uint64_t size; 1282 int nrows = 1; 1283 1284 size = vdev_draid_map_alloc_row(zio, &rr[0], io_offset, 1285 abd_offset, abd_size); 1286 if (size < abd_size) { 1287 vdev_t *vd = zio->io_vd; 1288 1289 io_offset += vdev_draid_psize_to_asize(vd, size, 0); 1290 abd_offset += size; 1291 abd_size -= size; 1292 nrows++; 1293 1294 ASSERT3U(io_offset, ==, vdev_draid_group_to_offset( 1295 vd, vdev_draid_offset_to_group(vd, io_offset))); 1296 ASSERT3U(abd_offset, <, zio->io_size); 1297 ASSERT3U(abd_size, !=, 0); 1298 1299 size = vdev_draid_map_alloc_row(zio, &rr[1], 1300 io_offset, abd_offset, abd_size); 1301 VERIFY3U(size, ==, abd_size); 1302 } 1303 1304 raidz_map_t *rm; 1305 rm = kmem_zalloc(offsetof(raidz_map_t, rm_row[nrows]), KM_SLEEP); 1306 rm->rm_ops = vdev_raidz_math_get_ops(); 1307 rm->rm_nrows = nrows; 1308 rm->rm_row[0] = rr[0]; 1309 if (nrows == 2) 1310 rm->rm_row[1] = rr[1]; 1311 return (rm); 1312 } 1313 1314 /* 1315 * Given an offset into a dRAID return the next group width aligned offset 1316 * which can be used to start an allocation. 1317 */ 1318 static uint64_t 1319 vdev_draid_get_astart(vdev_t *vd, const uint64_t start) 1320 { 1321 vdev_draid_config_t *vdc = vd->vdev_tsd; 1322 1323 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 1324 1325 return (roundup(start, vdc->vdc_groupwidth << vd->vdev_ashift)); 1326 } 1327 1328 /* 1329 * Allocatable space for dRAID is (children - nspares) * sizeof(smallest child) 1330 * rounded down to the last full slice. So each child must provide at least 1331 * 1 / (children - nspares) of its asize rounded up to VDEV_DRAID_ROWHEIGHT. 1332 */ 1333 static uint64_t 1334 vdev_draid_min_asize(vdev_t *vd) 1335 { 1336 vdev_draid_config_t *vdc = vd->vdev_tsd; 1337 1338 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 1339 1340 return (VDEV_DRAID_REFLOW_RESERVE + 1341 DIV_ROUND_UP(DIV_ROUND_UP(vd->vdev_min_asize, vdc->vdc_ndisks), 1342 VDEV_DRAID_ROWHEIGHT) * VDEV_DRAID_ROWHEIGHT); 1343 } 1344 1345 /* 1346 * When using dRAID the minimum allocation size is determined by the number 1347 * of data disks in the redundancy group. Full stripes are always used. 1348 */ 1349 static uint64_t 1350 vdev_draid_min_alloc(vdev_t *vd) 1351 { 1352 vdev_draid_config_t *vdc = vd->vdev_tsd; 1353 1354 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 1355 1356 return (vdc->vdc_ndata << vd->vdev_ashift); 1357 } 1358 1359 /* 1360 * Returns false if the txg range exists on any leaf vdev, true otherwise. 1361 * 1362 * A dRAID spare does not fit into the DTL model. While it has child vdevs 1363 * there is no redundancy among them, and the effective child vdev is 1364 * determined by offset. Essentially we do a vdev_dtl_reassess() on the 1365 * fly by replacing a dRAID spare with the child vdev under the offset. 1366 * Note that it is a recursive process because the child vdev can be 1367 * another dRAID spare and so on. 1368 */ 1369 boolean_t 1370 vdev_draid_missing(vdev_t *vd, uint64_t physical_offset, uint64_t txg, 1371 uint64_t size) 1372 { 1373 if (vd->vdev_ops == &vdev_spare_ops || 1374 vd->vdev_ops == &vdev_replacing_ops) { 1375 /* 1376 * Check all of the readable children, if any child 1377 * contains the txg range the data it is not missing. 1378 */ 1379 for (int c = 0; c < vd->vdev_children; c++) { 1380 vdev_t *cvd = vd->vdev_child[c]; 1381 1382 if (!vdev_readable(cvd)) 1383 continue; 1384 1385 if (!vdev_draid_missing(cvd, physical_offset, 1386 txg, size)) 1387 return (B_FALSE); 1388 } 1389 1390 return (B_TRUE); 1391 } 1392 1393 if (vd->vdev_ops == &vdev_draid_spare_ops) { 1394 /* 1395 * When sequentially resilvering we don't have a proper 1396 * txg range so instead we must presume all txgs are 1397 * missing on this vdev until the resilver completes. 1398 */ 1399 if (vd->vdev_rebuild_txg != 0) 1400 return (B_TRUE); 1401 1402 /* 1403 * DTL_MISSING is set for all prior txgs when a resilver 1404 * is started in spa_vdev_attach(). 1405 */ 1406 if (vdev_dtl_contains(vd, DTL_MISSING, txg, size)) 1407 return (B_TRUE); 1408 1409 /* 1410 * Consult the DTL on the relevant vdev. Either a vdev 1411 * leaf or spare/replace mirror child may be returned so 1412 * we must recursively call vdev_draid_missing_impl(). 1413 */ 1414 vd = vdev_draid_spare_get_child(vd, physical_offset); 1415 if (vd == NULL) 1416 return (B_TRUE); 1417 1418 return (vdev_draid_missing(vd, physical_offset, txg, size)); 1419 } 1420 1421 return (vdev_dtl_contains(vd, DTL_MISSING, txg, size)); 1422 } 1423 1424 /* 1425 * Returns true if the txg is only partially replicated on the leaf vdevs. 1426 */ 1427 static boolean_t 1428 vdev_draid_partial(vdev_t *vd, uint64_t physical_offset, uint64_t txg, 1429 uint64_t size) 1430 { 1431 if (vd->vdev_ops == &vdev_spare_ops || 1432 vd->vdev_ops == &vdev_replacing_ops) { 1433 /* 1434 * Check all of the readable children, if any child is 1435 * missing the txg range then it is partially replicated. 1436 */ 1437 for (int c = 0; c < vd->vdev_children; c++) { 1438 vdev_t *cvd = vd->vdev_child[c]; 1439 1440 if (!vdev_readable(cvd)) 1441 continue; 1442 1443 if (vdev_draid_partial(cvd, physical_offset, txg, size)) 1444 return (B_TRUE); 1445 } 1446 1447 return (B_FALSE); 1448 } 1449 1450 if (vd->vdev_ops == &vdev_draid_spare_ops) { 1451 /* 1452 * When sequentially resilvering we don't have a proper 1453 * txg range so instead we must presume all txgs are 1454 * missing on this vdev until the resilver completes. 1455 */ 1456 if (vd->vdev_rebuild_txg != 0) 1457 return (B_TRUE); 1458 1459 /* 1460 * DTL_MISSING is set for all prior txgs when a resilver 1461 * is started in spa_vdev_attach(). 1462 */ 1463 if (vdev_dtl_contains(vd, DTL_MISSING, txg, size)) 1464 return (B_TRUE); 1465 1466 /* 1467 * Consult the DTL on the relevant vdev. Either a vdev 1468 * leaf or spare/replace mirror child may be returned so 1469 * we must recursively call vdev_draid_missing_impl(). 1470 */ 1471 vd = vdev_draid_spare_get_child(vd, physical_offset); 1472 if (vd == NULL) 1473 return (B_TRUE); 1474 1475 return (vdev_draid_partial(vd, physical_offset, txg, size)); 1476 } 1477 1478 return (vdev_dtl_contains(vd, DTL_MISSING, txg, size)); 1479 } 1480 1481 /* 1482 * Determine if the vdev is readable at the given offset. 1483 */ 1484 boolean_t 1485 vdev_draid_readable(vdev_t *vd, uint64_t physical_offset) 1486 { 1487 if (vd->vdev_ops == &vdev_draid_spare_ops) { 1488 vd = vdev_draid_spare_get_child(vd, physical_offset); 1489 if (vd == NULL) 1490 return (B_FALSE); 1491 } 1492 1493 if (vd->vdev_ops == &vdev_spare_ops || 1494 vd->vdev_ops == &vdev_replacing_ops) { 1495 1496 for (int c = 0; c < vd->vdev_children; c++) { 1497 vdev_t *cvd = vd->vdev_child[c]; 1498 1499 if (!vdev_readable(cvd)) 1500 continue; 1501 1502 if (vdev_draid_readable(cvd, physical_offset)) 1503 return (B_TRUE); 1504 } 1505 1506 return (B_FALSE); 1507 } 1508 1509 return (vdev_readable(vd)); 1510 } 1511 1512 /* 1513 * Returns the first distributed spare found under the provided vdev tree. 1514 */ 1515 static vdev_t * 1516 vdev_draid_find_spare(vdev_t *vd) 1517 { 1518 if (vd->vdev_ops == &vdev_draid_spare_ops) 1519 return (vd); 1520 1521 for (int c = 0; c < vd->vdev_children; c++) { 1522 vdev_t *svd = vdev_draid_find_spare(vd->vdev_child[c]); 1523 if (svd != NULL) 1524 return (svd); 1525 } 1526 1527 return (NULL); 1528 } 1529 1530 /* 1531 * Returns B_TRUE if the passed in vdev is currently "faulted". 1532 * Faulted, in this context, means that the vdev represents a 1533 * replacing or sparing vdev tree. 1534 */ 1535 static boolean_t 1536 vdev_draid_faulted(vdev_t *vd, uint64_t physical_offset) 1537 { 1538 if (vd->vdev_ops == &vdev_draid_spare_ops) { 1539 vd = vdev_draid_spare_get_child(vd, physical_offset); 1540 if (vd == NULL) 1541 return (B_FALSE); 1542 1543 /* 1544 * After resolving the distributed spare to a leaf vdev 1545 * check the parent to determine if it's "faulted". 1546 */ 1547 vd = vd->vdev_parent; 1548 } 1549 1550 return (vd->vdev_ops == &vdev_replacing_ops || 1551 vd->vdev_ops == &vdev_spare_ops); 1552 } 1553 1554 /* 1555 * Determine if the dRAID block at the logical offset is degraded. 1556 * Used by sequential resilver. 1557 */ 1558 static boolean_t 1559 vdev_draid_group_degraded(vdev_t *vd, uint64_t offset) 1560 { 1561 vdev_draid_config_t *vdc = vd->vdev_tsd; 1562 1563 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 1564 ASSERT3U(vdev_draid_get_astart(vd, offset), ==, offset); 1565 1566 uint64_t groupstart, perm, ndisks; 1567 uint64_t physical_offset = vdev_draid_logical_to_physical(vd, 1568 offset, &perm, &groupstart, &ndisks); 1569 1570 uint8_t *base; 1571 uint64_t iter; 1572 vdev_draid_get_perm(vdc, perm, &base, &iter); 1573 1574 for (uint64_t i = 0; i < vdc->vdc_groupwidth; i++) { 1575 uint64_t c = (groupstart + i) % ndisks; 1576 uint64_t cid = vdev_draid_permute_id(vdc, base, iter, c); 1577 vdev_t *cvd = vd->vdev_child[cid]; 1578 1579 /* Group contains a faulted vdev. */ 1580 if (vdev_draid_faulted(cvd, physical_offset)) 1581 return (B_TRUE); 1582 1583 /* 1584 * Always check groups with active distributed spares 1585 * because any vdev failure in the pool will affect them. 1586 */ 1587 if (vdev_draid_find_spare(cvd) != NULL) 1588 return (B_TRUE); 1589 } 1590 1591 return (B_FALSE); 1592 } 1593 1594 /* 1595 * Determine if the txg is missing. Used by healing resilver. 1596 */ 1597 static boolean_t 1598 vdev_draid_group_missing(vdev_t *vd, uint64_t offset, uint64_t txg, 1599 uint64_t size) 1600 { 1601 vdev_draid_config_t *vdc = vd->vdev_tsd; 1602 1603 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 1604 ASSERT3U(vdev_draid_get_astart(vd, offset), ==, offset); 1605 1606 uint64_t groupstart, perm, ndisks; 1607 uint64_t physical_offset = vdev_draid_logical_to_physical(vd, 1608 offset, &perm, &groupstart, &ndisks); 1609 1610 uint8_t *base; 1611 uint64_t iter; 1612 vdev_draid_get_perm(vdc, perm, &base, &iter); 1613 1614 for (uint64_t i = 0; i < vdc->vdc_groupwidth; i++) { 1615 uint64_t c = (groupstart + i) % ndisks; 1616 uint64_t cid = vdev_draid_permute_id(vdc, base, iter, c); 1617 vdev_t *cvd = vd->vdev_child[cid]; 1618 1619 /* Transaction group is known to be partially replicated. */ 1620 if (vdev_draid_partial(cvd, physical_offset, txg, size)) 1621 return (B_TRUE); 1622 } 1623 1624 return (B_FALSE); 1625 } 1626 1627 /* 1628 * Find the smallest child asize and largest sector size to calculate the 1629 * available capacity. Distributed spares are ignored since their capacity 1630 * is also based of the minimum child size in the top-level dRAID. 1631 */ 1632 static void 1633 vdev_draid_calculate_asize(vdev_t *vd, uint64_t *asizep, uint64_t *max_asizep, 1634 uint64_t *logical_ashiftp, uint64_t *physical_ashiftp) 1635 { 1636 uint64_t logical_ashift = 0, physical_ashift = 0; 1637 uint64_t asize = 0, max_asize = 0; 1638 1639 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 1640 1641 for (int c = 0; c < vd->vdev_children; c++) { 1642 vdev_t *cvd = vd->vdev_child[c]; 1643 1644 if (cvd->vdev_ops == &vdev_draid_spare_ops) 1645 continue; 1646 1647 asize = MIN(asize - 1, cvd->vdev_asize - 1) + 1; 1648 max_asize = MIN(max_asize - 1, cvd->vdev_max_asize - 1) + 1; 1649 logical_ashift = MAX(logical_ashift, cvd->vdev_ashift); 1650 } 1651 for (int c = 0; c < vd->vdev_children; c++) { 1652 vdev_t *cvd = vd->vdev_child[c]; 1653 1654 if (cvd->vdev_ops == &vdev_draid_spare_ops) 1655 continue; 1656 physical_ashift = vdev_best_ashift(logical_ashift, 1657 physical_ashift, cvd->vdev_physical_ashift); 1658 } 1659 1660 *asizep = asize; 1661 *max_asizep = max_asize; 1662 *logical_ashiftp = logical_ashift; 1663 *physical_ashiftp = physical_ashift; 1664 } 1665 1666 /* 1667 * Open spare vdevs. 1668 */ 1669 static boolean_t 1670 vdev_draid_open_spares(vdev_t *vd) 1671 { 1672 return (vd->vdev_ops == &vdev_draid_spare_ops || 1673 vd->vdev_ops == &vdev_replacing_ops || 1674 vd->vdev_ops == &vdev_spare_ops); 1675 } 1676 1677 /* 1678 * Open all children, excluding spares. 1679 */ 1680 static boolean_t 1681 vdev_draid_open_children(vdev_t *vd) 1682 { 1683 return (!vdev_draid_open_spares(vd)); 1684 } 1685 1686 /* 1687 * Open a top-level dRAID vdev. 1688 */ 1689 static int 1690 vdev_draid_open(vdev_t *vd, uint64_t *asize, uint64_t *max_asize, 1691 uint64_t *logical_ashift, uint64_t *physical_ashift) 1692 { 1693 vdev_draid_config_t *vdc = vd->vdev_tsd; 1694 uint64_t nparity = vdc->vdc_nparity; 1695 int open_errors = 0; 1696 1697 if (nparity > VDEV_DRAID_MAXPARITY || 1698 vdc->vdc_children < nparity + 1) { 1699 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; 1700 return (SET_ERROR(EINVAL)); 1701 } 1702 1703 /* 1704 * First open the normal children then the distributed spares. This 1705 * ordering is important to ensure the distributed spares calculate 1706 * the correct psize in the event that the dRAID vdevs were expanded. 1707 */ 1708 vdev_open_children_subset(vd, vdev_draid_open_children); 1709 vdev_open_children_subset(vd, vdev_draid_open_spares); 1710 1711 /* 1712 * Verify enough of the children are available to continue. 1713 * If several disks got failed on i-th position in each slice in the 1714 * big width row (failure groups) - they are counted as one failure, 1715 * but only if the failures threshold is not reached in any group. 1716 */ 1717 boolean_t safe2skip = B_FALSE; 1718 if (vdc->vdc_width > vdc->vdc_children && 1719 vdev_draid_fail_domain_allowed(vd)) 1720 safe2skip = B_TRUE; 1721 for (int c = 0; c < vdc->vdc_children; c++) { 1722 for (int i = c; i < vdc->vdc_width; i += vdc->vdc_children) { 1723 if (vd->vdev_child[i]->vdev_open_error != 0) { 1724 if ((++open_errors) > nparity) { 1725 vd->vdev_stat.vs_aux = 1726 VDEV_AUX_NO_REPLICAS; 1727 return (SET_ERROR(ENXIO)); 1728 } 1729 if (safe2skip) 1730 break; 1731 } 1732 } 1733 } 1734 1735 /* 1736 * Allocatable capacity is the sum of the space on all children less 1737 * the number of distributed spares rounded down to last full row 1738 * and then to the last full group. An additional 32MB of scratch 1739 * space is reserved at the end of each child for use by the dRAID 1740 * expansion feature. 1741 */ 1742 uint64_t child_asize, child_max_asize; 1743 vdev_draid_calculate_asize(vd, &child_asize, &child_max_asize, 1744 logical_ashift, physical_ashift); 1745 1746 /* 1747 * Should be unreachable since the minimum child size is 64MB, but 1748 * we want to make sure an underflow absolutely cannot occur here. 1749 */ 1750 if (child_asize < VDEV_DRAID_REFLOW_RESERVE || 1751 child_max_asize < VDEV_DRAID_REFLOW_RESERVE) { 1752 return (SET_ERROR(ENXIO)); 1753 } 1754 1755 child_asize = ((child_asize - VDEV_DRAID_REFLOW_RESERVE) / 1756 VDEV_DRAID_ROWHEIGHT) * VDEV_DRAID_ROWHEIGHT; 1757 child_max_asize = ((child_max_asize - VDEV_DRAID_REFLOW_RESERVE) / 1758 VDEV_DRAID_ROWHEIGHT) * VDEV_DRAID_ROWHEIGHT; 1759 1760 *asize = (((child_asize * vdc->vdc_ndisks) / vdc->vdc_groupsz) * 1761 vdc->vdc_groupsz); 1762 *max_asize = (((child_max_asize * vdc->vdc_ndisks) / vdc->vdc_groupsz) * 1763 vdc->vdc_groupsz); 1764 1765 /* 1766 * For failure groups with multiple silices in the big width row, 1767 * round down to the big slice size. 1768 */ 1769 if (vdc->vdc_width > vdc->vdc_children) { 1770 uint64_t slicesz = vdc->vdc_devslicesz * vdc->vdc_ndisks; 1771 *asize = (*asize / slicesz) * slicesz; 1772 *max_asize = (*max_asize / slicesz) * slicesz; 1773 } 1774 1775 return (0); 1776 } 1777 1778 /* 1779 * Close a top-level dRAID vdev. 1780 */ 1781 static void 1782 vdev_draid_close(vdev_t *vd) 1783 { 1784 for (int c = 0; c < vd->vdev_children; c++) { 1785 if (vd->vdev_child[c] != NULL) 1786 vdev_close(vd->vdev_child[c]); 1787 } 1788 } 1789 1790 /* 1791 * Return the maximum asize for a rebuild zio in the provided range 1792 * given the following constraints. A dRAID chunks may not: 1793 * 1794 * - Exceed the maximum allowed block size (SPA_MAXBLOCKSIZE), or 1795 * - Span dRAID redundancy groups. 1796 */ 1797 static uint64_t 1798 vdev_draid_rebuild_asize(vdev_t *vd, uint64_t start, uint64_t asize, 1799 uint64_t max_segment) 1800 { 1801 vdev_draid_config_t *vdc = vd->vdev_tsd; 1802 1803 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 1804 1805 uint64_t ashift = vd->vdev_ashift; 1806 uint64_t ndata = vdc->vdc_ndata; 1807 uint64_t psize = MIN(P2ROUNDUP(max_segment * ndata, 1 << ashift), 1808 SPA_MAXBLOCKSIZE); 1809 1810 ASSERT3U(vdev_draid_get_astart(vd, start), ==, start); 1811 ASSERT0(asize % (vdc->vdc_groupwidth << ashift)); 1812 1813 /* Chunks must evenly span all data columns in the group. */ 1814 psize = (((psize >> ashift) / ndata) * ndata) << ashift; 1815 uint64_t chunk_size = MIN(asize, vdev_psize_to_asize(vd, psize)); 1816 1817 /* Reduce the chunk size to the group space remaining. */ 1818 uint64_t group = vdev_draid_offset_to_group(vd, start); 1819 uint64_t left = vdev_draid_group_to_offset(vd, group + 1) - start; 1820 chunk_size = MIN(chunk_size, left); 1821 1822 ASSERT0(chunk_size % (vdc->vdc_groupwidth << ashift)); 1823 ASSERT3U(vdev_draid_offset_to_group(vd, start), ==, 1824 vdev_draid_offset_to_group(vd, start + chunk_size - 1)); 1825 1826 return (chunk_size); 1827 } 1828 1829 /* 1830 * Align the start of the metaslab to the group width and slightly reduce 1831 * its size to a multiple of the group width. Since full stripe writes are 1832 * required by dRAID this space is unallocable. Furthermore, aligning the 1833 * metaslab start is important for vdev initialize and TRIM which both operate 1834 * on metaslab boundaries which vdev_xlate() expects to be aligned. 1835 */ 1836 static void 1837 vdev_draid_metaslab_init(vdev_t *vd, uint64_t *ms_start, uint64_t *ms_size) 1838 { 1839 vdev_draid_config_t *vdc = vd->vdev_tsd; 1840 1841 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 1842 1843 uint64_t sz = vdc->vdc_groupwidth << vd->vdev_ashift; 1844 uint64_t astart = vdev_draid_get_astart(vd, *ms_start); 1845 uint64_t asize = ((*ms_size - (astart - *ms_start)) / sz) * sz; 1846 1847 *ms_start = astart; 1848 *ms_size = asize; 1849 1850 ASSERT0(*ms_start % sz); 1851 ASSERT0(*ms_size % sz); 1852 } 1853 1854 /* 1855 * Add virtual dRAID spares to the list of valid spares. In order to accomplish 1856 * this the existing array must be freed and reallocated with the additional 1857 * entries. 1858 */ 1859 int 1860 vdev_draid_spare_create(nvlist_t *nvroot, vdev_t *vd, uint64_t *ndraidp, 1861 uint64_t *nfgroupp, uint64_t next_vdev_id) 1862 { 1863 uint64_t draid_nspares = 0; 1864 uint64_t ndraid = 0; 1865 uint64_t nfgroup = 0; 1866 int error; 1867 1868 for (uint64_t i = 0; i < vd->vdev_children; i++) { 1869 vdev_t *cvd = vd->vdev_child[i]; 1870 1871 if (cvd->vdev_ops == &vdev_draid_ops) { 1872 vdev_draid_config_t *vdc = cvd->vdev_tsd; 1873 draid_nspares += vdc->vdc_nspares; 1874 ndraid++; 1875 if (vdc->vdc_width > vdc->vdc_children) 1876 nfgroup++; 1877 } 1878 } 1879 1880 if (draid_nspares == 0) { 1881 *ndraidp = ndraid; 1882 *nfgroupp = nfgroup; 1883 return (0); 1884 } 1885 1886 nvlist_t **old_spares, **new_spares; 1887 uint_t old_nspares; 1888 error = nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES, 1889 &old_spares, &old_nspares); 1890 if (error) 1891 old_nspares = 0; 1892 1893 /* Allocate memory and copy of the existing spares. */ 1894 new_spares = kmem_alloc(sizeof (nvlist_t *) * 1895 (draid_nspares + old_nspares), KM_SLEEP); 1896 for (uint_t i = 0; i < old_nspares; i++) 1897 new_spares[i] = fnvlist_dup(old_spares[i]); 1898 1899 /* Add new distributed spares to ZPOOL_CONFIG_SPARES. */ 1900 uint64_t n = old_nspares; 1901 for (uint64_t vdev_id = 0; vdev_id < vd->vdev_children; vdev_id++) { 1902 vdev_t *cvd = vd->vdev_child[vdev_id]; 1903 char path[64]; 1904 1905 if (cvd->vdev_ops != &vdev_draid_ops) 1906 continue; 1907 1908 vdev_draid_config_t *vdc = cvd->vdev_tsd; 1909 uint64_t nspares = vdc->vdc_nspares; 1910 uint64_t nparity = vdc->vdc_nparity; 1911 1912 for (uint64_t spare_id = 0; spare_id < nspares; spare_id++) { 1913 memset(path, 0, sizeof (path)); 1914 (void) snprintf(path, sizeof (path) - 1, 1915 "%s%llu-%llu-%llu", VDEV_TYPE_DRAID, 1916 (u_longlong_t)nparity, 1917 (u_longlong_t)next_vdev_id + vdev_id, 1918 (u_longlong_t)spare_id); 1919 1920 nvlist_t *spare = fnvlist_alloc(); 1921 fnvlist_add_string(spare, ZPOOL_CONFIG_PATH, path); 1922 fnvlist_add_string(spare, ZPOOL_CONFIG_TYPE, 1923 VDEV_TYPE_DRAID_SPARE); 1924 fnvlist_add_uint64(spare, ZPOOL_CONFIG_TOP_GUID, 1925 cvd->vdev_guid); 1926 fnvlist_add_uint64(spare, ZPOOL_CONFIG_SPARE_ID, 1927 spare_id); 1928 fnvlist_add_uint64(spare, ZPOOL_CONFIG_IS_LOG, 0); 1929 fnvlist_add_uint64(spare, ZPOOL_CONFIG_IS_SPARE, 1); 1930 fnvlist_add_uint64(spare, ZPOOL_CONFIG_WHOLE_DISK, 1); 1931 fnvlist_add_uint64(spare, ZPOOL_CONFIG_ASHIFT, 1932 cvd->vdev_ashift); 1933 1934 new_spares[n] = spare; 1935 n++; 1936 } 1937 } 1938 1939 if (n > 0) { 1940 (void) nvlist_remove_all(nvroot, ZPOOL_CONFIG_SPARES); 1941 fnvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES, 1942 (const nvlist_t **)new_spares, n); 1943 } 1944 1945 for (int i = 0; i < n; i++) 1946 nvlist_free(new_spares[i]); 1947 1948 kmem_free(new_spares, sizeof (*new_spares) * n); 1949 *ndraidp = ndraid; 1950 *nfgroupp = nfgroup; 1951 1952 return (0); 1953 } 1954 1955 /* 1956 * Determine if any portion of the provided block resides on a child vdev 1957 * with a dirty DTL and therefore needs to be resilvered. 1958 */ 1959 static boolean_t 1960 vdev_draid_need_resilver(vdev_t *vd, const dva_t *dva, size_t psize, 1961 uint64_t phys_birth) 1962 { 1963 uint64_t offset = DVA_GET_OFFSET(dva); 1964 uint64_t asize = vdev_draid_psize_to_asize(vd, psize, 0); 1965 1966 if (phys_birth == TXG_UNKNOWN) { 1967 /* 1968 * Sequential resilver. There is no meaningful phys_birth 1969 * for this block, we can only determine if block resides 1970 * in a degraded group in which case it must be resilvered. 1971 */ 1972 ASSERT3U(vdev_draid_offset_to_group(vd, offset), ==, 1973 vdev_draid_offset_to_group(vd, offset + asize - 1)); 1974 1975 return (vdev_draid_group_degraded(vd, offset)); 1976 } else { 1977 /* 1978 * Healing resilver. TXGs not in DTL_PARTIAL are intact, 1979 * as are blocks in non-degraded groups. 1980 */ 1981 if (!vdev_dtl_contains(vd, DTL_PARTIAL, phys_birth, 1)) 1982 return (B_FALSE); 1983 1984 if (vdev_draid_group_missing(vd, offset, phys_birth, 1)) 1985 return (B_TRUE); 1986 1987 /* The block may span groups in which case check both. */ 1988 if (vdev_draid_offset_to_group(vd, offset) != 1989 vdev_draid_offset_to_group(vd, offset + asize - 1)) { 1990 if (vdev_draid_group_missing(vd, 1991 offset + asize, phys_birth, 1)) 1992 return (B_TRUE); 1993 } 1994 1995 return (B_FALSE); 1996 } 1997 } 1998 1999 static boolean_t 2000 vdev_draid_rebuilding(vdev_t *vd) 2001 { 2002 if (vd->vdev_ops->vdev_op_leaf && vd->vdev_rebuild_txg) 2003 return (B_TRUE); 2004 2005 for (int i = 0; i < vd->vdev_children; i++) { 2006 if (vdev_draid_rebuilding(vd->vdev_child[i])) { 2007 return (B_TRUE); 2008 } 2009 } 2010 2011 return (B_FALSE); 2012 } 2013 2014 static void 2015 vdev_draid_io_verify(vdev_t *vd, raidz_row_t *rr, int col) 2016 { 2017 #ifdef ZFS_DEBUG 2018 zfs_range_seg64_t logical_rs, physical_rs, remain_rs; 2019 logical_rs.rs_start = rr->rr_offset; 2020 logical_rs.rs_end = logical_rs.rs_start + 2021 vdev_draid_psize_to_asize(vd, rr->rr_size, 0); 2022 2023 raidz_col_t *rc = &rr->rr_col[col]; 2024 vdev_t *cvd = vd->vdev_child[rc->rc_devidx]; 2025 2026 vdev_xlate(cvd, &logical_rs, &physical_rs, &remain_rs); 2027 ASSERT(vdev_xlate_is_empty(&remain_rs)); 2028 ASSERT3U(rc->rc_offset, ==, physical_rs.rs_start); 2029 ASSERT3U(rc->rc_offset, <, physical_rs.rs_end); 2030 ASSERT3U(rc->rc_offset + rc->rc_size, ==, physical_rs.rs_end); 2031 #endif 2032 } 2033 2034 /* 2035 * For write operations: 2036 * 1. Generate the parity data 2037 * 2. Create child zio write operations to each column's vdev, for both 2038 * data and parity. A gang ABD is allocated by vdev_draid_map_alloc() 2039 * if a skip sector needs to be added to a column. 2040 */ 2041 static void 2042 vdev_draid_io_start_write(zio_t *zio, raidz_row_t *rr) 2043 { 2044 vdev_t *vd = zio->io_vd; 2045 raidz_map_t *rm = zio->io_vsd; 2046 2047 vdev_raidz_generate_parity_row(rm, rr); 2048 2049 for (int c = 0; c < rr->rr_cols; c++) { 2050 raidz_col_t *rc = &rr->rr_col[c]; 2051 2052 /* 2053 * Empty columns are zero filled and included in the parity 2054 * calculation and therefore must be written. 2055 */ 2056 ASSERT3U(rc->rc_size, !=, 0); 2057 2058 /* Verify physical to logical translation */ 2059 vdev_draid_io_verify(vd, rr, c); 2060 2061 zio_nowait(zio_vdev_child_io(zio, NULL, 2062 vd->vdev_child[rc->rc_devidx], rc->rc_offset, 2063 rc->rc_abd, rc->rc_size, zio->io_type, zio->io_priority, 2064 0, vdev_raidz_child_done, rc)); 2065 } 2066 } 2067 2068 /* 2069 * For read operations: 2070 * 1. The vdev_draid_map_alloc() function will create a minimal raidz 2071 * mapping for the read based on the zio->io_flags. There are two 2072 * possible mappings either 1) a normal read, or 2) a scrub/resilver. 2073 * 2. Create the zio read operations. This will include all parity 2074 * columns and skip sectors for a scrub/resilver. 2075 */ 2076 static void 2077 vdev_draid_io_start_read(zio_t *zio, raidz_row_t *rr) 2078 { 2079 vdev_t *vd = zio->io_vd; 2080 2081 /* Sequential rebuild must do IO at redundancy group boundary. */ 2082 IMPLY(zio->io_priority == ZIO_PRIORITY_REBUILD, rr->rr_nempty == 0); 2083 2084 /* 2085 * Iterate over the columns in reverse order so that we hit the parity 2086 * last. Any errors along the way will force us to read the parity. 2087 * For scrub/resilver IOs which verify skip sectors, a gang ABD will 2088 * have been allocated to store them and rc->rc_size is increased. 2089 */ 2090 for (int c = rr->rr_cols - 1; c >= 0; c--) { 2091 raidz_col_t *rc = &rr->rr_col[c]; 2092 vdev_t *cvd = vd->vdev_child[rc->rc_devidx]; 2093 2094 if (!vdev_draid_readable(cvd, rc->rc_offset)) { 2095 if (c >= rr->rr_firstdatacol) 2096 rr->rr_missingdata++; 2097 else 2098 rr->rr_missingparity++; 2099 rc->rc_error = SET_ERROR(ENXIO); 2100 rc->rc_tried = 1; 2101 rc->rc_skipped = 1; 2102 continue; 2103 } 2104 2105 if (vdev_draid_missing(cvd, rc->rc_offset, zio->io_txg, 1)) { 2106 vdev_t *svd; 2107 2108 if (c >= rr->rr_firstdatacol) 2109 rr->rr_missingdata++; 2110 else 2111 rr->rr_missingparity++; 2112 rc->rc_error = SET_ERROR(ESTALE); 2113 rc->rc_skipped = 1; 2114 2115 /* 2116 * If this child has draid spare attached, and that 2117 * spare by rc_offset maps to another spare, the repair 2118 * would go to that spare, and we want all mirrored 2119 * children on it to be updated with the repaired data, 2120 * even when we cannot vouch for it during rebuilds 2121 * (which don't have checksums). Otherwise, we will have 2122 * a lot of checksum errors on that spares during scrub. 2123 * The worst thing that can happen in this case is that 2124 * we will update the reserved spare column on some 2125 * device with unverified data, which is harmless. 2126 */ 2127 if ((svd = vdev_draid_find_spare(cvd)) != NULL) { 2128 svd = vdev_draid_spare_get_child(svd, 2129 rc->rc_offset); 2130 if (svd && (svd->vdev_ops == &vdev_spare_ops || 2131 svd->vdev_ops == &vdev_replacing_ops)) 2132 rc->rc_tgt_is_dspare = 1; 2133 } 2134 continue; 2135 } 2136 2137 /* 2138 * Empty columns may be read during vdev_draid_io_done(). 2139 * Only skip them after the readable and missing checks 2140 * verify they are available. 2141 */ 2142 if (rc->rc_size == 0) { 2143 rc->rc_skipped = 1; 2144 continue; 2145 } 2146 2147 if (zio->io_flags & ZIO_FLAG_RESILVER) { 2148 vdev_t *svd; 2149 2150 /* 2151 * Repairs need to be constrained to the devices being 2152 * rebuilt since without a checksum we cannot verify the 2153 * data is actually correct and performing an incorrect 2154 * repair could result in locking in the damage and 2155 * making the data unrecoverable. 2156 */ 2157 if (zio->io_priority == ZIO_PRIORITY_REBUILD && 2158 !vdev_draid_rebuilding(cvd)) 2159 rc->rc_allow_repair = 0; 2160 2161 /* 2162 * If this child is a distributed spare then the 2163 * offset might reside on the vdev being replaced. 2164 * In which case this data must be written to the 2165 * new device. Failure to do so would result in 2166 * checksum errors when the old device is detached 2167 * and the pool is scrubbed. 2168 */ 2169 if ((svd = vdev_draid_find_spare(cvd)) != NULL) { 2170 svd = vdev_draid_spare_get_child(svd, 2171 rc->rc_offset); 2172 if (svd && (svd->vdev_ops == &vdev_spare_ops || 2173 svd->vdev_ops == &vdev_replacing_ops)) { 2174 rc->rc_force_repair = 1; 2175 2176 if (vdev_draid_rebuilding(svd)) 2177 rc->rc_allow_repair = 1; 2178 } 2179 } 2180 2181 /* 2182 * Always issue a repair IO to this child when its 2183 * a spare or replacing vdev with an active rebuild. 2184 */ 2185 if ((cvd->vdev_ops == &vdev_spare_ops || 2186 cvd->vdev_ops == &vdev_replacing_ops) && 2187 vdev_draid_rebuilding(cvd)) { 2188 rc->rc_force_repair = 1; 2189 rc->rc_allow_repair = 1; 2190 } 2191 } 2192 2193 if (vdev_sit_out_reads(cvd, zio->io_flags)) { 2194 rr->rr_outlier_cnt++; 2195 ASSERT0(rc->rc_latency_outlier); 2196 rc->rc_latency_outlier = 1; 2197 } 2198 } 2199 2200 /* 2201 * When the row contains a latency outlier and sufficient parity 2202 * exists to reconstruct the column data, then skip reading the 2203 * known slow child vdev as a performance optimization. 2204 */ 2205 if (rr->rr_outlier_cnt > 0 && 2206 (rr->rr_firstdatacol - rr->rr_missingparity) >= 2207 (rr->rr_missingdata + 1)) { 2208 2209 for (int c = rr->rr_cols - 1; c >= rr->rr_firstdatacol; c--) { 2210 raidz_col_t *rc = &rr->rr_col[c]; 2211 2212 if (rc->rc_error == 0 && rc->rc_latency_outlier) { 2213 rr->rr_missingdata++; 2214 rc->rc_error = SET_ERROR(EAGAIN); 2215 rc->rc_skipped = 1; 2216 break; 2217 } 2218 } 2219 } 2220 2221 /* 2222 * Either a parity or data column is missing this means a repair 2223 * may be attempted by vdev_draid_io_done(). Expand the raid map 2224 * to read in empty columns which are needed along with the parity 2225 * during reconstruction. 2226 */ 2227 if ((rr->rr_missingdata > 0 || rr->rr_missingparity > 0) && 2228 rr->rr_nempty > 0 && rr->rr_abd_empty == NULL) { 2229 vdev_draid_map_alloc_empty(zio, rr); 2230 } 2231 2232 for (int c = rr->rr_cols - 1; c >= 0; c--) { 2233 raidz_col_t *rc = &rr->rr_col[c]; 2234 vdev_t *cvd = vd->vdev_child[rc->rc_devidx]; 2235 2236 if (rc->rc_error || rc->rc_size == 0) 2237 continue; 2238 2239 if (c >= rr->rr_firstdatacol || rr->rr_missingdata > 0 || 2240 (zio->io_flags & (ZIO_FLAG_SCRUB | ZIO_FLAG_RESILVER))) { 2241 zio_nowait(zio_vdev_child_io(zio, NULL, cvd, 2242 rc->rc_offset, rc->rc_abd, rc->rc_size, 2243 zio->io_type, zio->io_priority, 0, 2244 vdev_raidz_child_done, rc)); 2245 } 2246 } 2247 } 2248 2249 /* 2250 * Start an IO operation to a dRAID vdev. 2251 */ 2252 static void 2253 vdev_draid_io_start(zio_t *zio) 2254 { 2255 vdev_t *vd __maybe_unused = zio->io_vd; 2256 2257 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 2258 ASSERT3U(zio->io_offset, ==, vdev_draid_get_astart(vd, zio->io_offset)); 2259 2260 raidz_map_t *rm = vdev_draid_map_alloc(zio); 2261 zio->io_vsd = rm; 2262 zio->io_vsd_ops = &vdev_raidz_vsd_ops; 2263 2264 if (zio->io_type == ZIO_TYPE_WRITE) { 2265 for (int i = 0; i < rm->rm_nrows; i++) { 2266 vdev_draid_io_start_write(zio, rm->rm_row[i]); 2267 } 2268 } else { 2269 ASSERT(zio->io_type == ZIO_TYPE_READ); 2270 2271 for (int i = 0; i < rm->rm_nrows; i++) { 2272 vdev_draid_io_start_read(zio, rm->rm_row[i]); 2273 } 2274 } 2275 2276 zio_execute(zio); 2277 } 2278 2279 /* 2280 * Complete an IO operation on a dRAID vdev. The raidz logic can be applied 2281 * to dRAID since the layout is fully described by the raidz_map_t. 2282 */ 2283 static void 2284 vdev_draid_io_done(zio_t *zio) 2285 { 2286 vdev_raidz_io_done(zio); 2287 } 2288 2289 static void 2290 vdev_draid_state_change(vdev_t *vd, int faulted, int degraded) 2291 { 2292 vdev_draid_config_t *vdc = vd->vdev_tsd; 2293 ASSERT(vd->vdev_ops == &vdev_draid_ops); 2294 2295 if (faulted > vdc->vdc_nparity * (vdc->vdc_width / vdc->vdc_children)) 2296 vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN, 2297 VDEV_AUX_NO_REPLICAS); 2298 else if (degraded + faulted != 0) 2299 vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE); 2300 else 2301 vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE); 2302 } 2303 2304 static void 2305 vdev_draid_xlate(vdev_t *cvd, const zfs_range_seg64_t *logical_rs, 2306 zfs_range_seg64_t *physical_rs, zfs_range_seg64_t *remain_rs) 2307 { 2308 vdev_t *raidvd = cvd->vdev_parent; 2309 ASSERT(raidvd->vdev_ops == &vdev_draid_ops); 2310 2311 vdev_draid_config_t *vdc = raidvd->vdev_tsd; 2312 uint64_t ashift = raidvd->vdev_top->vdev_ashift; 2313 2314 /* Make sure the offsets are block-aligned */ 2315 ASSERT0(logical_rs->rs_start % (1 << ashift)); 2316 ASSERT0(logical_rs->rs_end % (1 << ashift)); 2317 2318 uint64_t logical_start = logical_rs->rs_start; 2319 uint64_t logical_end = logical_rs->rs_end; 2320 2321 /* 2322 * Unaligned ranges must be skipped. All metaslabs are correctly 2323 * aligned so this should not happen, but this case is handled in 2324 * case it's needed by future callers. 2325 */ 2326 uint64_t astart = vdev_draid_get_astart(raidvd, logical_start); 2327 if (astart != logical_start) { 2328 physical_rs->rs_start = logical_start; 2329 physical_rs->rs_end = logical_start; 2330 remain_rs->rs_start = MIN(astart, logical_end); 2331 remain_rs->rs_end = logical_end; 2332 return; 2333 } 2334 2335 /* 2336 * Unlike with mirrors and raidz a dRAID logical range can map 2337 * to multiple non-contiguous physical ranges. This is handled by 2338 * limiting the size of the logical range to a single group and 2339 * setting the remain argument such that it describes the remaining 2340 * unmapped logical range. This is stricter than absolutely 2341 * necessary but helps simplify the logic below. 2342 */ 2343 uint64_t group = vdev_draid_offset_to_group(raidvd, logical_start); 2344 uint64_t nextstart = vdev_draid_group_to_offset(raidvd, group + 1); 2345 if (logical_end > nextstart) 2346 logical_end = nextstart; 2347 2348 /* Find the starting offset for each vdev in the group */ 2349 uint64_t perm, groupstart, ndisks; 2350 uint64_t start = vdev_draid_logical_to_physical(raidvd, 2351 logical_start, &perm, &groupstart, &ndisks); 2352 uint64_t end = start; 2353 2354 uint8_t *base; 2355 uint64_t iter, id; 2356 vdev_draid_get_perm(vdc, perm, &base, &iter); 2357 2358 /* 2359 * Check if the passed child falls within the group. If it does 2360 * update the start and end to reflect the physical range. 2361 * Otherwise, leave them unmodified which will result in an empty 2362 * (zero-length) physical range being returned. 2363 */ 2364 for (uint64_t i = 0; i < vdc->vdc_groupwidth; i++) { 2365 uint64_t c = (groupstart + i) % ndisks; 2366 2367 if (c == 0 && i != 0) { 2368 /* the group wrapped, increment the start */ 2369 start += VDEV_DRAID_ROWHEIGHT; 2370 end = start; 2371 } 2372 2373 id = vdev_draid_permute_id(vdc, base, iter, c); 2374 if (id == cvd->vdev_id) { 2375 uint64_t b_size = (logical_end >> ashift) - 2376 (logical_start >> ashift); 2377 ASSERT3U(b_size, >, 0); 2378 end = start + ((((b_size - 1) / 2379 vdc->vdc_groupwidth) + 1) << ashift); 2380 break; 2381 } 2382 } 2383 physical_rs->rs_start = start; 2384 physical_rs->rs_end = end; 2385 2386 /* 2387 * Only top-level vdevs are allowed to set remain_rs because 2388 * when .vdev_op_xlate() is called for their children the full 2389 * logical range is not provided by vdev_xlate(). 2390 */ 2391 remain_rs->rs_start = logical_end; 2392 remain_rs->rs_end = logical_rs->rs_end; 2393 2394 ASSERT3U(physical_rs->rs_start, <=, logical_start); 2395 ASSERT3U(physical_rs->rs_end - physical_rs->rs_start, <=, 2396 logical_end - logical_start); 2397 } 2398 2399 /* 2400 * Add dRAID specific fields to the config nvlist. 2401 */ 2402 static void 2403 vdev_draid_config_generate(vdev_t *vd, nvlist_t *nv) 2404 { 2405 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 2406 vdev_draid_config_t *vdc = vd->vdev_tsd; 2407 2408 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NPARITY, vdc->vdc_nparity); 2409 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DRAID_NDATA, vdc->vdc_ndata); 2410 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DRAID_NSPARES, vdc->vdc_nspares); 2411 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DRAID_NGROUPS, vdc->vdc_ngroups); 2412 2413 if (spa_feature_is_active(vd->vdev_spa, SPA_FEATURE_DRAID_FAIL_DOMAINS)) 2414 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DRAID_NCHILDREN, 2415 vdc->vdc_children); 2416 } 2417 2418 /* 2419 * Initialize private dRAID specific fields from the nvlist. 2420 */ 2421 static int 2422 vdev_draid_init(spa_t *spa, nvlist_t *nv, void **tsd) 2423 { 2424 (void) spa; 2425 uint64_t ndata, nparity, nspares, ngroups; 2426 int error; 2427 2428 if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DRAID_NDATA, &ndata)) 2429 return (SET_ERROR(EINVAL)); 2430 2431 if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_NPARITY, &nparity) || 2432 nparity == 0 || nparity > VDEV_DRAID_MAXPARITY) { 2433 return (SET_ERROR(EINVAL)); 2434 } 2435 2436 uint_t width; 2437 uint64_t children; 2438 nvlist_t **child; 2439 if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN, 2440 &child, &width) != 0 || width == 0) { 2441 return (SET_ERROR(EINVAL)); 2442 } 2443 2444 if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DRAID_NCHILDREN, &children)) { 2445 children = width; 2446 if (children > VDEV_DRAID_MAX_CHILDREN) 2447 return (SET_ERROR(EINVAL)); 2448 } 2449 2450 if (children == 0 || width % children != 0) 2451 return (SET_ERROR(EINVAL)); 2452 2453 if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DRAID_NSPARES, &nspares) || 2454 nspares > 100) { 2455 return (SET_ERROR(EINVAL)); 2456 } 2457 2458 int fgrps = width / children; 2459 int nspare = nspares / fgrps; 2460 if (nspares % fgrps) 2461 nspare++; 2462 2463 /* 2464 * Validate the minimum number of children exist per group for the 2465 * specified parity level (draid1 >= 2, draid2 >= 3, draid3 >= 4). 2466 */ 2467 if (children < (ndata + nparity + nspare)) 2468 return (SET_ERROR(EINVAL)); 2469 2470 if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DRAID_NGROUPS, &ngroups) || 2471 ngroups == 0 || ngroups > VDEV_DRAID_MAX_CHILDREN) { 2472 return (SET_ERROR(EINVAL)); 2473 } 2474 2475 /* 2476 * Create the dRAID configuration using the pool nvlist configuration 2477 * and the fixed mapping for the correct number of children. 2478 */ 2479 vdev_draid_config_t *vdc; 2480 const draid_map_t *map; 2481 2482 error = vdev_draid_lookup_map(children, &map); 2483 if (error) 2484 return (SET_ERROR(EINVAL)); 2485 2486 vdc = kmem_zalloc(sizeof (*vdc), KM_SLEEP); 2487 vdc->vdc_ndata = ndata; 2488 vdc->vdc_nparity = nparity; 2489 vdc->vdc_nspares = nspares; 2490 vdc->vdc_children = children; 2491 vdc->vdc_ngroups = ngroups; 2492 vdc->vdc_width = width; 2493 vdc->vdc_nperms = map->dm_nperms; 2494 2495 error = vdev_draid_generate_perms(map, &vdc->vdc_perms); 2496 if (error) { 2497 kmem_free(vdc, sizeof (*vdc)); 2498 return (SET_ERROR(EINVAL)); 2499 } 2500 2501 if (width > children) 2502 vdev_draid_shuffle_perms(map, vdc->vdc_perms, width); 2503 2504 /* 2505 * Derived constants. 2506 */ 2507 vdc->vdc_groupwidth = vdc->vdc_ndata + vdc->vdc_nparity; 2508 vdc->vdc_ndisks = vdc->vdc_width - vdc->vdc_nspares; 2509 vdc->vdc_groupsz = vdc->vdc_groupwidth * VDEV_DRAID_ROWHEIGHT; 2510 vdc->vdc_devslicesz = (vdc->vdc_groupsz * vdc->vdc_ngroups) / 2511 vdc->vdc_ndisks; 2512 2513 ASSERT3U(vdc->vdc_groupwidth, >=, 2); 2514 ASSERT3U(vdc->vdc_groupwidth, <=, vdc->vdc_ndisks); 2515 ASSERT3U(vdc->vdc_groupsz, >=, 2 * VDEV_DRAID_ROWHEIGHT); 2516 ASSERT3U(vdc->vdc_devslicesz, >=, VDEV_DRAID_ROWHEIGHT); 2517 ASSERT0(vdc->vdc_devslicesz % VDEV_DRAID_ROWHEIGHT); 2518 ASSERT3U((vdc->vdc_groupwidth * vdc->vdc_ngroups) % 2519 vdc->vdc_ndisks, ==, 0); 2520 2521 *tsd = vdc; 2522 2523 return (0); 2524 } 2525 2526 static void 2527 vdev_draid_fini(vdev_t *vd) 2528 { 2529 vdev_draid_config_t *vdc = vd->vdev_tsd; 2530 2531 vmem_free(vdc->vdc_perms, sizeof (uint8_t) * 2532 vdc->vdc_children * vdc->vdc_nperms); 2533 kmem_free(vdc, sizeof (*vdc)); 2534 } 2535 2536 static uint64_t 2537 vdev_draid_nparity(vdev_t *vd) 2538 { 2539 vdev_draid_config_t *vdc = vd->vdev_tsd; 2540 2541 return (vdc->vdc_nparity * (vdc->vdc_width / vdc->vdc_children)); 2542 } 2543 2544 static uint64_t 2545 vdev_draid_ndisks(vdev_t *vd) 2546 { 2547 vdev_draid_config_t *vdc = vd->vdev_tsd; 2548 2549 return (vdc->vdc_ndisks); 2550 } 2551 2552 vdev_ops_t vdev_draid_ops = { 2553 .vdev_op_init = vdev_draid_init, 2554 .vdev_op_fini = vdev_draid_fini, 2555 .vdev_op_open = vdev_draid_open, 2556 .vdev_op_close = vdev_draid_close, 2557 .vdev_op_psize_to_asize = vdev_draid_psize_to_asize, 2558 .vdev_op_asize_to_psize = vdev_draid_asize_to_psize, 2559 .vdev_op_min_asize = vdev_draid_min_asize, 2560 .vdev_op_min_alloc = vdev_draid_min_alloc, 2561 .vdev_op_io_start = vdev_draid_io_start, 2562 .vdev_op_io_done = vdev_draid_io_done, 2563 .vdev_op_state_change = vdev_draid_state_change, 2564 .vdev_op_need_resilver = vdev_draid_need_resilver, 2565 .vdev_op_hold = NULL, 2566 .vdev_op_rele = NULL, 2567 .vdev_op_remap = NULL, 2568 .vdev_op_xlate = vdev_draid_xlate, 2569 .vdev_op_rebuild_asize = vdev_draid_rebuild_asize, 2570 .vdev_op_metaslab_init = vdev_draid_metaslab_init, 2571 .vdev_op_config_generate = vdev_draid_config_generate, 2572 .vdev_op_nparity = vdev_draid_nparity, 2573 .vdev_op_ndisks = vdev_draid_ndisks, 2574 .vdev_op_type = VDEV_TYPE_DRAID, 2575 .vdev_op_leaf = B_FALSE, 2576 }; 2577 2578 2579 /* 2580 * A dRAID distributed spare is a virtual leaf vdev which is included in the 2581 * parent dRAID configuration. The last N columns of the dRAID permutation 2582 * table are used to determine on which dRAID children a specific offset 2583 * should be written. These spare leaf vdevs can only be used to replace 2584 * faulted children in the same dRAID configuration. 2585 */ 2586 2587 /* 2588 * Distributed spare state. All fields are set when the distributed spare is 2589 * first opened and are immutable. 2590 */ 2591 typedef struct { 2592 vdev_t *vds_draid_vdev; /* top-level parent dRAID vdev */ 2593 uint64_t vds_top_guid; /* top-level parent dRAID guid */ 2594 uint64_t vds_spare_id; /* spare id (0 - vdc->vdc_nspares-1) */ 2595 } vdev_draid_spare_t; 2596 2597 /* 2598 * Returns the parent dRAID vdev to which the distributed spare belongs. 2599 * This may be safely called even when the vdev is not open. 2600 */ 2601 vdev_t * 2602 vdev_draid_spare_get_parent(vdev_t *vd) 2603 { 2604 vdev_draid_spare_t *vds = vd->vdev_tsd; 2605 2606 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_spare_ops); 2607 2608 if (vds->vds_draid_vdev != NULL) 2609 return (vds->vds_draid_vdev); 2610 2611 return (vdev_lookup_by_guid(vd->vdev_spa->spa_root_vdev, 2612 vds->vds_top_guid)); 2613 } 2614 2615 /* 2616 * A dRAID space is active when it's the child of a vdev using the 2617 * vdev_spare_ops, vdev_replacing_ops or vdev_draid_ops. 2618 */ 2619 static boolean_t 2620 vdev_draid_spare_is_active(vdev_t *vd) 2621 { 2622 vdev_t *pvd = vd->vdev_parent; 2623 2624 if (pvd != NULL && (pvd->vdev_ops == &vdev_spare_ops || 2625 pvd->vdev_ops == &vdev_replacing_ops || 2626 pvd->vdev_ops == &vdev_draid_ops)) { 2627 return (B_TRUE); 2628 } else { 2629 return (B_FALSE); 2630 } 2631 } 2632 2633 /* 2634 * Given a dRAID distribute spare vdev, returns the physical child vdev 2635 * on which the provided offset resides. This may involve recursing through 2636 * multiple layers of distributed spares. Note that offset is relative to 2637 * this vdev. 2638 */ 2639 vdev_t * 2640 vdev_draid_spare_get_child(vdev_t *vd, uint64_t physical_offset) 2641 { 2642 vdev_draid_spare_t *vds = vd->vdev_tsd; 2643 2644 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_spare_ops); 2645 2646 /* The vdev is closed */ 2647 if (vds->vds_draid_vdev == NULL) 2648 return (NULL); 2649 2650 vdev_t *tvd = vds->vds_draid_vdev; 2651 vdev_draid_config_t *vdc = tvd->vdev_tsd; 2652 2653 uint64_t fgrps = vdc->vdc_width / vdc->vdc_children; 2654 2655 ASSERT3P(tvd->vdev_ops, ==, &vdev_draid_ops); 2656 ASSERT3U(vds->vds_spare_id, <, vdc->vdc_nspares); 2657 2658 uint8_t *base; 2659 uint64_t iter; 2660 uint64_t perm = (physical_offset / vdc->vdc_devslicesz) * fgrps; 2661 2662 /* 2663 * Adjust permutation so that it points to the correct slice in the 2664 * big width row. 2665 */ 2666 perm += vds->vds_spare_id % fgrps; 2667 2668 vdev_draid_get_perm(vdc, perm, &base, &iter); 2669 2670 uint64_t cid = vdev_draid_permute_id(vdc, base, iter, 2671 (vdc->vdc_children - 1) - (vds->vds_spare_id / fgrps)); 2672 vdev_t *cvd = tvd->vdev_child[cid]; 2673 2674 if (cvd->vdev_ops == &vdev_draid_spare_ops) 2675 return (vdev_draid_spare_get_child(cvd, physical_offset)); 2676 2677 return (cvd); 2678 } 2679 2680 /* 2681 * Returns true if no failure group reached failures threshold so that 2682 * enclosure failure cannot be tolerated anymore. Used spares are counted 2683 * as failures because in case of enclosure failure their blocks can belong 2684 * to the disks from that enclosure and can be lost. 2685 */ 2686 boolean_t 2687 vdev_draid_fail_domain_allowed(vdev_t *vd) 2688 { 2689 vdev_draid_config_t *vdc = vd->vdev_tsd; 2690 2691 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); 2692 ASSERT3P(vdc->vdc_width, >, vdc->vdc_children); 2693 2694 int counter = 0; 2695 2696 for (int c = 0; c < vdc->vdc_width; c++) { 2697 vdev_t *cvd = vd->vdev_child[c]; 2698 2699 if ((c % vdc->vdc_children) == 0) 2700 counter = 0; 2701 2702 if (cvd->vdev_ops == &vdev_spare_ops || 2703 cvd->vdev_ops == &vdev_draid_spare_ops || 2704 !vdev_readable(cvd)) 2705 counter++; 2706 2707 if (counter > vdc->vdc_nparity) 2708 return (B_FALSE); 2709 } 2710 2711 return (B_TRUE); 2712 } 2713 2714 static void 2715 vdev_draid_spare_close(vdev_t *vd) 2716 { 2717 vdev_draid_spare_t *vds = vd->vdev_tsd; 2718 vds->vds_draid_vdev = NULL; 2719 } 2720 2721 /* 2722 * Opening a dRAID spare device is done by looking up the associated dRAID 2723 * top-level vdev guid from the spare configuration. 2724 */ 2725 static int 2726 vdev_draid_spare_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize, 2727 uint64_t *logical_ashift, uint64_t *physical_ashift) 2728 { 2729 vdev_draid_spare_t *vds = vd->vdev_tsd; 2730 vdev_t *rvd = vd->vdev_spa->spa_root_vdev; 2731 uint64_t asize, max_asize; 2732 2733 vdev_t *tvd = vdev_lookup_by_guid(rvd, vds->vds_top_guid); 2734 if (tvd == NULL) { 2735 /* 2736 * When spa_vdev_add() is labeling new spares the 2737 * associated dRAID is not attached to the root vdev 2738 * nor does this spare have a parent. Simulate a valid 2739 * device in order to allow the label to be initialized 2740 * and the distributed spare added to the configuration. 2741 */ 2742 if (vd->vdev_parent == NULL) { 2743 *psize = *max_psize = SPA_MINDEVSIZE; 2744 *logical_ashift = *physical_ashift = ASHIFT_MIN; 2745 return (0); 2746 } 2747 2748 return (SET_ERROR(EINVAL)); 2749 } 2750 2751 vdev_draid_config_t *vdc = tvd->vdev_tsd; 2752 if (tvd->vdev_ops != &vdev_draid_ops || vdc == NULL) 2753 return (SET_ERROR(EINVAL)); 2754 2755 if (vds->vds_spare_id >= vdc->vdc_nspares) 2756 return (SET_ERROR(EINVAL)); 2757 2758 /* 2759 * Neither tvd->vdev_asize or tvd->vdev_max_asize can be used here 2760 * because the caller may be vdev_draid_open() in which case the 2761 * values are stale as they haven't yet been updated by vdev_open(). 2762 * To avoid this always recalculate the dRAID asize and max_asize. 2763 */ 2764 vdev_draid_calculate_asize(tvd, &asize, &max_asize, 2765 logical_ashift, physical_ashift); 2766 2767 *psize = asize + VDEV_LABEL_START_SIZE + VDEV_LABEL_END_SIZE; 2768 *max_psize = max_asize + VDEV_LABEL_START_SIZE + VDEV_LABEL_END_SIZE; 2769 2770 vds->vds_draid_vdev = tvd; 2771 vd->vdev_nonrot = tvd->vdev_nonrot; 2772 2773 return (0); 2774 } 2775 2776 /* 2777 * Completed distributed spare IO. Store the result in the parent zio 2778 * as if it had performed the operation itself. Only the first error is 2779 * preserved if there are multiple errors. 2780 */ 2781 static void 2782 vdev_draid_spare_child_done(zio_t *zio) 2783 { 2784 zio_t *pio = zio->io_private; 2785 2786 /* 2787 * IOs are issued to non-writable vdevs in order to keep their 2788 * DTLs accurate. However, we don't want to propagate the 2789 * error in to the distributed spare's DTL. When resilvering 2790 * vdev_draid_need_resilver() will consult the relevant DTL 2791 * to determine if the data is missing and must be repaired. 2792 */ 2793 if (!vdev_writeable(zio->io_vd)) 2794 return; 2795 2796 if (pio->io_error == 0) 2797 pio->io_error = zio->io_error; 2798 } 2799 2800 /* 2801 * Returns a valid label nvlist for the distributed spare vdev. This is 2802 * used to bypass the IO pipeline to avoid the complexity of constructing 2803 * a complete label with valid checksum to return when read. 2804 */ 2805 nvlist_t * 2806 vdev_draid_read_config_spare(vdev_t *vd) 2807 { 2808 spa_t *spa = vd->vdev_spa; 2809 spa_aux_vdev_t *sav = &spa->spa_spares; 2810 uint64_t guid = vd->vdev_guid; 2811 2812 nvlist_t *nv = fnvlist_alloc(); 2813 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_SPARE, 1); 2814 fnvlist_add_uint64(nv, ZPOOL_CONFIG_CREATE_TXG, vd->vdev_crtxg); 2815 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VERSION, spa_version(spa)); 2816 fnvlist_add_string(nv, ZPOOL_CONFIG_POOL_NAME, spa_name(spa)); 2817 fnvlist_add_uint64(nv, ZPOOL_CONFIG_POOL_GUID, spa_guid(spa)); 2818 fnvlist_add_uint64(nv, ZPOOL_CONFIG_POOL_TXG, spa->spa_config_txg); 2819 fnvlist_add_uint64(nv, ZPOOL_CONFIG_TOP_GUID, vd->vdev_top->vdev_guid); 2820 fnvlist_add_uint64(nv, ZPOOL_CONFIG_POOL_STATE, 2821 vdev_draid_spare_is_active(vd) ? 2822 POOL_STATE_ACTIVE : POOL_STATE_SPARE); 2823 2824 /* Set the vdev guid based on the vdev list in sav_count. */ 2825 for (int i = 0; i < sav->sav_count; i++) { 2826 if (sav->sav_vdevs[i]->vdev_ops == &vdev_draid_spare_ops && 2827 strcmp(sav->sav_vdevs[i]->vdev_path, vd->vdev_path) == 0) { 2828 guid = sav->sav_vdevs[i]->vdev_guid; 2829 break; 2830 } 2831 } 2832 2833 fnvlist_add_uint64(nv, ZPOOL_CONFIG_GUID, guid); 2834 2835 return (nv); 2836 } 2837 2838 /* 2839 * Handle any flush requested of the distributed spare. All children must be 2840 * flushed. 2841 */ 2842 static int 2843 vdev_draid_spare_flush(zio_t *zio) 2844 { 2845 vdev_t *vd = zio->io_vd; 2846 int error = 0; 2847 2848 for (int c = 0; c < vd->vdev_children; c++) { 2849 zio_nowait(zio_vdev_child_io(zio, NULL, 2850 vd->vdev_child[c], zio->io_offset, zio->io_abd, 2851 zio->io_size, zio->io_type, zio->io_priority, 0, 2852 vdev_draid_spare_child_done, zio)); 2853 } 2854 2855 return (error); 2856 } 2857 2858 /* 2859 * Initiate an IO to the distributed spare. For normal IOs this entails using 2860 * the zio->io_offset and permutation table to calculate which child dRAID vdev 2861 * is responsible for the data. Then passing along the zio to that child to 2862 * perform the actual IO. The label ranges are not stored on disk and require 2863 * some special handling which is described below. 2864 */ 2865 static void 2866 vdev_draid_spare_io_start(zio_t *zio) 2867 { 2868 vdev_t *cvd = NULL, *vd = zio->io_vd; 2869 vdev_draid_spare_t *vds = vd->vdev_tsd; 2870 uint64_t offset = zio->io_offset - VDEV_LABEL_START_SIZE; 2871 2872 /* 2873 * If the vdev is closed, it's likely in the REMOVED or FAULTED state. 2874 * Nothing to be done here but return failure. 2875 */ 2876 if (vds == NULL) { 2877 zio->io_error = ENXIO; 2878 zio_interrupt(zio); 2879 return; 2880 } 2881 2882 switch (zio->io_type) { 2883 case ZIO_TYPE_FLUSH: 2884 zio->io_error = vdev_draid_spare_flush(zio); 2885 break; 2886 2887 case ZIO_TYPE_WRITE: 2888 if (VDEV_OFFSET_IS_LABEL(vd, zio->io_offset)) { 2889 /* 2890 * Accept probe IOs and config writers to simulate the 2891 * existence of an on disk label. vdev_label_sync(), 2892 * vdev_uberblock_sync() and vdev_copy_uberblocks() 2893 * skip the distributed spares. This only leaves 2894 * vdev_label_init() which is allowed to succeed to 2895 * avoid adding special cases the function. 2896 */ 2897 if (zio->io_flags & ZIO_FLAG_PROBE || 2898 zio->io_flags & ZIO_FLAG_CONFIG_WRITER) { 2899 zio->io_error = 0; 2900 } else { 2901 zio->io_error = SET_ERROR(EIO); 2902 } 2903 } else { 2904 cvd = vdev_draid_spare_get_child(vd, offset); 2905 2906 if (cvd == NULL) { 2907 zio->io_error = SET_ERROR(ENXIO); 2908 } else { 2909 zio_nowait(zio_vdev_child_io(zio, NULL, cvd, 2910 offset, zio->io_abd, zio->io_size, 2911 zio->io_type, zio->io_priority, 0, 2912 vdev_draid_spare_child_done, zio)); 2913 } 2914 } 2915 break; 2916 2917 case ZIO_TYPE_READ: 2918 if (VDEV_OFFSET_IS_LABEL(vd, zio->io_offset)) { 2919 /* 2920 * Accept probe IOs to simulate the existence of a 2921 * label. vdev_label_read_config() bypasses the 2922 * pipeline to read the label configuration and 2923 * vdev_uberblock_load() skips distributed spares 2924 * when attempting to locate the best uberblock. 2925 */ 2926 if (zio->io_flags & ZIO_FLAG_PROBE) { 2927 zio->io_error = 0; 2928 } else { 2929 zio->io_error = SET_ERROR(EIO); 2930 } 2931 } else { 2932 cvd = vdev_draid_spare_get_child(vd, offset); 2933 2934 if (cvd == NULL || !vdev_readable(cvd)) { 2935 zio->io_error = SET_ERROR(ENXIO); 2936 } else { 2937 zio_nowait(zio_vdev_child_io(zio, NULL, cvd, 2938 offset, zio->io_abd, zio->io_size, 2939 zio->io_type, zio->io_priority, 0, 2940 vdev_draid_spare_child_done, zio)); 2941 } 2942 } 2943 break; 2944 2945 case ZIO_TYPE_TRIM: 2946 /* The vdev label ranges are never trimmed */ 2947 ASSERT0(VDEV_OFFSET_IS_LABEL(vd, zio->io_offset)); 2948 2949 cvd = vdev_draid_spare_get_child(vd, offset); 2950 2951 if (cvd == NULL || !cvd->vdev_has_trim) { 2952 zio->io_error = SET_ERROR(ENXIO); 2953 } else { 2954 zio_nowait(zio_vdev_child_io(zio, NULL, cvd, 2955 offset, zio->io_abd, zio->io_size, 2956 zio->io_type, zio->io_priority, 0, 2957 vdev_draid_spare_child_done, zio)); 2958 } 2959 break; 2960 2961 default: 2962 zio->io_error = SET_ERROR(ENOTSUP); 2963 break; 2964 } 2965 2966 zio_execute(zio); 2967 } 2968 2969 static void 2970 vdev_draid_spare_io_done(zio_t *zio) 2971 { 2972 (void) zio; 2973 } 2974 2975 /* 2976 * Lookup the full spare config in spa->spa_spares.sav_config and 2977 * return the top_guid and spare_id for the named spare. 2978 */ 2979 static int 2980 vdev_draid_spare_lookup(spa_t *spa, nvlist_t *nv, uint64_t *top_guidp, 2981 uint64_t *spare_idp) 2982 { 2983 nvlist_t **spares; 2984 uint_t nspares; 2985 int error; 2986 2987 if ((spa->spa_spares.sav_config == NULL) || 2988 (nvlist_lookup_nvlist_array(spa->spa_spares.sav_config, 2989 ZPOOL_CONFIG_SPARES, &spares, &nspares) != 0)) { 2990 return (SET_ERROR(ENOENT)); 2991 } 2992 2993 const char *spare_name; 2994 error = nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &spare_name); 2995 if (error != 0) 2996 return (SET_ERROR(EINVAL)); 2997 2998 for (int i = 0; i < nspares; i++) { 2999 nvlist_t *spare = spares[i]; 3000 uint64_t top_guid, spare_id; 3001 const char *type, *path; 3002 3003 /* Skip non-distributed spares */ 3004 error = nvlist_lookup_string(spare, ZPOOL_CONFIG_TYPE, &type); 3005 if (error != 0 || strcmp(type, VDEV_TYPE_DRAID_SPARE) != 0) 3006 continue; 3007 3008 /* Skip spares with the wrong name */ 3009 error = nvlist_lookup_string(spare, ZPOOL_CONFIG_PATH, &path); 3010 if (error != 0 || strcmp(path, spare_name) != 0) 3011 continue; 3012 3013 /* Found the matching spare */ 3014 error = nvlist_lookup_uint64(spare, 3015 ZPOOL_CONFIG_TOP_GUID, &top_guid); 3016 if (error == 0) { 3017 error = nvlist_lookup_uint64(spare, 3018 ZPOOL_CONFIG_SPARE_ID, &spare_id); 3019 } 3020 3021 if (error != 0) { 3022 return (SET_ERROR(EINVAL)); 3023 } else { 3024 *top_guidp = top_guid; 3025 *spare_idp = spare_id; 3026 return (0); 3027 } 3028 } 3029 3030 return (SET_ERROR(ENOENT)); 3031 } 3032 3033 /* 3034 * Initialize private dRAID spare specific fields from the nvlist. 3035 */ 3036 static int 3037 vdev_draid_spare_init(spa_t *spa, nvlist_t *nv, void **tsd) 3038 { 3039 vdev_draid_spare_t *vds; 3040 uint64_t top_guid = 0; 3041 uint64_t spare_id; 3042 3043 /* 3044 * In the normal case check the list of spares stored in the spa 3045 * to lookup the top_guid and spare_id for provided spare config. 3046 * When creating a new pool or adding vdevs the spare list is not 3047 * yet populated and the values are provided in the passed config. 3048 */ 3049 if (vdev_draid_spare_lookup(spa, nv, &top_guid, &spare_id) != 0) { 3050 if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_TOP_GUID, 3051 &top_guid) != 0) 3052 return (SET_ERROR(EINVAL)); 3053 3054 if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_SPARE_ID, 3055 &spare_id) != 0) 3056 return (SET_ERROR(EINVAL)); 3057 } 3058 3059 vds = kmem_alloc(sizeof (vdev_draid_spare_t), KM_SLEEP); 3060 vds->vds_draid_vdev = NULL; 3061 vds->vds_top_guid = top_guid; 3062 vds->vds_spare_id = spare_id; 3063 3064 *tsd = vds; 3065 3066 return (0); 3067 } 3068 3069 static void 3070 vdev_draid_spare_fini(vdev_t *vd) 3071 { 3072 kmem_free(vd->vdev_tsd, sizeof (vdev_draid_spare_t)); 3073 } 3074 3075 static void 3076 vdev_draid_spare_config_generate(vdev_t *vd, nvlist_t *nv) 3077 { 3078 vdev_draid_spare_t *vds = vd->vdev_tsd; 3079 3080 ASSERT3P(vd->vdev_ops, ==, &vdev_draid_spare_ops); 3081 3082 fnvlist_add_uint64(nv, ZPOOL_CONFIG_TOP_GUID, vds->vds_top_guid); 3083 fnvlist_add_uint64(nv, ZPOOL_CONFIG_SPARE_ID, vds->vds_spare_id); 3084 } 3085 3086 vdev_ops_t vdev_draid_spare_ops = { 3087 .vdev_op_init = vdev_draid_spare_init, 3088 .vdev_op_fini = vdev_draid_spare_fini, 3089 .vdev_op_open = vdev_draid_spare_open, 3090 .vdev_op_close = vdev_draid_spare_close, 3091 .vdev_op_psize_to_asize = vdev_default_asize, 3092 .vdev_op_asize_to_psize = vdev_default_psize, 3093 .vdev_op_min_asize = vdev_default_min_asize, 3094 .vdev_op_min_alloc = NULL, 3095 .vdev_op_io_start = vdev_draid_spare_io_start, 3096 .vdev_op_io_done = vdev_draid_spare_io_done, 3097 .vdev_op_state_change = NULL, 3098 .vdev_op_need_resilver = NULL, 3099 .vdev_op_hold = NULL, 3100 .vdev_op_rele = NULL, 3101 .vdev_op_remap = NULL, 3102 .vdev_op_xlate = vdev_default_xlate, 3103 .vdev_op_rebuild_asize = NULL, 3104 .vdev_op_metaslab_init = NULL, 3105 .vdev_op_config_generate = vdev_draid_spare_config_generate, 3106 .vdev_op_nparity = NULL, 3107 .vdev_op_ndisks = NULL, 3108 .vdev_op_type = VDEV_TYPE_DRAID_SPARE, 3109 .vdev_op_leaf = B_TRUE, 3110 }; 3111