1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or https://opensource.org/licenses/CDDL-1.0. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2012, 2020 by Delphix. All rights reserved. 25 * Copyright (c) 2017, Intel Corporation. 26 */ 27 28 /* 29 * Virtual Device Labels 30 * --------------------- 31 * 32 * The vdev label serves several distinct purposes: 33 * 34 * 1. Uniquely identify this device as part of a ZFS pool and confirm its 35 * identity within the pool. 36 * 37 * 2. Verify that all the devices given in a configuration are present 38 * within the pool. 39 * 40 * 3. Determine the uberblock for the pool. 41 * 42 * 4. In case of an import operation, determine the configuration of the 43 * toplevel vdev of which it is a part. 44 * 45 * 5. If an import operation cannot find all the devices in the pool, 46 * provide enough information to the administrator to determine which 47 * devices are missing. 48 * 49 * It is important to note that while the kernel is responsible for writing the 50 * label, it only consumes the information in the first three cases. The 51 * latter information is only consumed in userland when determining the 52 * configuration to import a pool. 53 * 54 * 55 * Label Organization 56 * ------------------ 57 * 58 * Before describing the contents of the label, it's important to understand how 59 * the labels are written and updated with respect to the uberblock. 60 * 61 * When the pool configuration is altered, either because it was newly created 62 * or a device was added, we want to update all the labels such that we can deal 63 * with fatal failure at any point. To this end, each disk has two labels which 64 * are updated before and after the uberblock is synced. Assuming we have 65 * labels and an uberblock with the following transaction groups: 66 * 67 * L1 UB L2 68 * +------+ +------+ +------+ 69 * | | | | | | 70 * | t10 | | t10 | | t10 | 71 * | | | | | | 72 * +------+ +------+ +------+ 73 * 74 * In this stable state, the labels and the uberblock were all updated within 75 * the same transaction group (10). Each label is mirrored and checksummed, so 76 * that we can detect when we fail partway through writing the label. 77 * 78 * In order to identify which labels are valid, the labels are written in the 79 * following manner: 80 * 81 * 1. For each vdev, update 'L1' to the new label 82 * 2. Update the uberblock 83 * 3. For each vdev, update 'L2' to the new label 84 * 85 * Given arbitrary failure, we can determine the correct label to use based on 86 * the transaction group. If we fail after updating L1 but before updating the 87 * UB, we will notice that L1's transaction group is greater than the uberblock, 88 * so L2 must be valid. If we fail after writing the uberblock but before 89 * writing L2, we will notice that L2's transaction group is less than L1, and 90 * therefore L1 is valid. 91 * 92 * Another added complexity is that not every label is updated when the config 93 * is synced. If we add a single device, we do not want to have to re-write 94 * every label for every device in the pool. This means that both L1 and L2 may 95 * be older than the pool uberblock, because the necessary information is stored 96 * on another vdev. 97 * 98 * 99 * On-disk Format 100 * -------------- 101 * 102 * The vdev label consists of two distinct parts, and is wrapped within the 103 * vdev_label_t structure. The label includes 8k of padding to permit legacy 104 * VTOC disk labels, but is otherwise ignored. 105 * 106 * The first half of the label is a packed nvlist which contains pool wide 107 * properties, per-vdev properties, and configuration information. It is 108 * described in more detail below. 109 * 110 * The latter half of the label consists of a redundant array of uberblocks. 111 * These uberblocks are updated whenever a transaction group is committed, 112 * or when the configuration is updated. When a pool is loaded, we scan each 113 * vdev for the 'best' uberblock. 114 * 115 * 116 * Configuration Information 117 * ------------------------- 118 * 119 * The nvlist describing the pool and vdev contains the following elements: 120 * 121 * version ZFS on-disk version 122 * name Pool name 123 * state Pool state 124 * txg Transaction group in which this label was written 125 * pool_guid Unique identifier for this pool 126 * vdev_tree An nvlist describing vdev tree. 127 * features_for_read 128 * An nvlist of the features necessary for reading the MOS. 129 * 130 * Each leaf device label also contains the following: 131 * 132 * top_guid Unique ID for top-level vdev in which this is contained 133 * guid Unique ID for the leaf vdev 134 * 135 * The 'vs' configuration follows the format described in 'spa_config.c'. 136 */ 137 138 #include <sys/zfs_context.h> 139 #include <sys/spa.h> 140 #include <sys/spa_impl.h> 141 #include <sys/dmu.h> 142 #include <sys/zap.h> 143 #include <sys/vdev.h> 144 #include <sys/vdev_impl.h> 145 #include <sys/vdev_draid.h> 146 #include <sys/uberblock_impl.h> 147 #include <sys/metaslab.h> 148 #include <sys/metaslab_impl.h> 149 #include <sys/zio.h> 150 #include <sys/dsl_scan.h> 151 #include <sys/abd.h> 152 #include <sys/fs/zfs.h> 153 #include <sys/byteorder.h> 154 #include <sys/zfs_bootenv.h> 155 156 /* 157 * Basic routines to read and write from a vdev label. 158 * Used throughout the rest of this file. 159 */ 160 uint64_t 161 vdev_label_offset(uint64_t psize, int l, uint64_t offset) 162 { 163 ASSERT(offset < sizeof (vdev_label_t)); 164 ASSERT(P2PHASE_TYPED(psize, sizeof (vdev_label_t), uint64_t) == 0); 165 166 return (offset + l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ? 167 0 : psize - VDEV_LABELS * sizeof (vdev_label_t))); 168 } 169 170 /* 171 * Returns back the vdev label associated with the passed in offset. 172 */ 173 int 174 vdev_label_number(uint64_t psize, uint64_t offset) 175 { 176 int l; 177 178 if (offset >= psize - VDEV_LABEL_END_SIZE) { 179 offset -= psize - VDEV_LABEL_END_SIZE; 180 offset += (VDEV_LABELS / 2) * sizeof (vdev_label_t); 181 } 182 l = offset / sizeof (vdev_label_t); 183 return (l < VDEV_LABELS ? l : -1); 184 } 185 186 static void 187 vdev_label_read(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset, 188 uint64_t size, zio_done_func_t *done, void *private, int flags) 189 { 190 ASSERT( 191 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE || 192 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE); 193 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER); 194 195 zio_nowait(zio_read_phys(zio, vd, 196 vdev_label_offset(vd->vdev_psize, l, offset), 197 size, buf, ZIO_CHECKSUM_LABEL, done, private, 198 ZIO_PRIORITY_SYNC_READ, flags, B_TRUE)); 199 } 200 201 void 202 vdev_label_write(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset, 203 uint64_t size, zio_done_func_t *done, void *private, int flags) 204 { 205 ASSERT( 206 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE || 207 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE); 208 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER); 209 210 zio_nowait(zio_write_phys(zio, vd, 211 vdev_label_offset(vd->vdev_psize, l, offset), 212 size, buf, ZIO_CHECKSUM_LABEL, done, private, 213 ZIO_PRIORITY_SYNC_WRITE, flags, B_TRUE)); 214 } 215 216 /* 217 * Generate the nvlist representing this vdev's stats 218 */ 219 void 220 vdev_config_generate_stats(vdev_t *vd, nvlist_t *nv) 221 { 222 nvlist_t *nvx; 223 vdev_stat_t *vs; 224 vdev_stat_ex_t *vsx; 225 226 vs = kmem_alloc(sizeof (*vs), KM_SLEEP); 227 vsx = kmem_alloc(sizeof (*vsx), KM_SLEEP); 228 229 vdev_get_stats_ex(vd, vs, vsx); 230 fnvlist_add_uint64_array(nv, ZPOOL_CONFIG_VDEV_STATS, 231 (uint64_t *)vs, sizeof (*vs) / sizeof (uint64_t)); 232 233 /* 234 * Add extended stats into a special extended stats nvlist. This keeps 235 * all the extended stats nicely grouped together. The extended stats 236 * nvlist is then added to the main nvlist. 237 */ 238 nvx = fnvlist_alloc(); 239 240 /* ZIOs in flight to disk */ 241 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_ACTIVE_QUEUE, 242 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_READ]); 243 244 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_ACTIVE_QUEUE, 245 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_WRITE]); 246 247 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_ACTIVE_QUEUE, 248 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_READ]); 249 250 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_ACTIVE_QUEUE, 251 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_WRITE]); 252 253 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_ACTIVE_QUEUE, 254 vsx->vsx_active_queue[ZIO_PRIORITY_SCRUB]); 255 256 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_ACTIVE_QUEUE, 257 vsx->vsx_active_queue[ZIO_PRIORITY_TRIM]); 258 259 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_REBUILD_ACTIVE_QUEUE, 260 vsx->vsx_active_queue[ZIO_PRIORITY_REBUILD]); 261 262 /* ZIOs pending */ 263 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_PEND_QUEUE, 264 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_READ]); 265 266 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_PEND_QUEUE, 267 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_WRITE]); 268 269 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_PEND_QUEUE, 270 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_READ]); 271 272 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_PEND_QUEUE, 273 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_WRITE]); 274 275 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_PEND_QUEUE, 276 vsx->vsx_pend_queue[ZIO_PRIORITY_SCRUB]); 277 278 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_PEND_QUEUE, 279 vsx->vsx_pend_queue[ZIO_PRIORITY_TRIM]); 280 281 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_REBUILD_PEND_QUEUE, 282 vsx->vsx_pend_queue[ZIO_PRIORITY_REBUILD]); 283 284 /* Histograms */ 285 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_R_LAT_HISTO, 286 vsx->vsx_total_histo[ZIO_TYPE_READ], 287 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_READ])); 288 289 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_W_LAT_HISTO, 290 vsx->vsx_total_histo[ZIO_TYPE_WRITE], 291 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_WRITE])); 292 293 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_R_LAT_HISTO, 294 vsx->vsx_disk_histo[ZIO_TYPE_READ], 295 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_READ])); 296 297 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_W_LAT_HISTO, 298 vsx->vsx_disk_histo[ZIO_TYPE_WRITE], 299 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_WRITE])); 300 301 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_LAT_HISTO, 302 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ], 303 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ])); 304 305 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_LAT_HISTO, 306 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE], 307 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE])); 308 309 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_LAT_HISTO, 310 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ], 311 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ])); 312 313 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_LAT_HISTO, 314 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE], 315 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE])); 316 317 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SCRUB_LAT_HISTO, 318 vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB], 319 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB])); 320 321 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TRIM_LAT_HISTO, 322 vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM], 323 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM])); 324 325 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_REBUILD_LAT_HISTO, 326 vsx->vsx_queue_histo[ZIO_PRIORITY_REBUILD], 327 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_REBUILD])); 328 329 /* Request sizes */ 330 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_R_HISTO, 331 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ], 332 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ])); 333 334 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_W_HISTO, 335 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE], 336 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE])); 337 338 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_R_HISTO, 339 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ], 340 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ])); 341 342 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_W_HISTO, 343 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE], 344 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE])); 345 346 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_SCRUB_HISTO, 347 vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB], 348 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB])); 349 350 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_TRIM_HISTO, 351 vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM], 352 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM])); 353 354 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_REBUILD_HISTO, 355 vsx->vsx_ind_histo[ZIO_PRIORITY_REBUILD], 356 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_REBUILD])); 357 358 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_R_HISTO, 359 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ], 360 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ])); 361 362 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_W_HISTO, 363 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE], 364 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE])); 365 366 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_R_HISTO, 367 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ], 368 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ])); 369 370 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_W_HISTO, 371 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE], 372 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE])); 373 374 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_SCRUB_HISTO, 375 vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB], 376 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB])); 377 378 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_TRIM_HISTO, 379 vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM], 380 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM])); 381 382 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_REBUILD_HISTO, 383 vsx->vsx_agg_histo[ZIO_PRIORITY_REBUILD], 384 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_REBUILD])); 385 386 /* IO delays */ 387 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SLOW_IOS, vs->vs_slow_ios); 388 389 /* Add extended stats nvlist to main nvlist */ 390 fnvlist_add_nvlist(nv, ZPOOL_CONFIG_VDEV_STATS_EX, nvx); 391 392 fnvlist_free(nvx); 393 kmem_free(vs, sizeof (*vs)); 394 kmem_free(vsx, sizeof (*vsx)); 395 } 396 397 static void 398 root_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl) 399 { 400 spa_t *spa = vd->vdev_spa; 401 402 if (vd != spa->spa_root_vdev) 403 return; 404 405 /* provide either current or previous scan information */ 406 pool_scan_stat_t ps; 407 if (spa_scan_get_stats(spa, &ps) == 0) { 408 fnvlist_add_uint64_array(nvl, 409 ZPOOL_CONFIG_SCAN_STATS, (uint64_t *)&ps, 410 sizeof (pool_scan_stat_t) / sizeof (uint64_t)); 411 } 412 413 pool_removal_stat_t prs; 414 if (spa_removal_get_stats(spa, &prs) == 0) { 415 fnvlist_add_uint64_array(nvl, 416 ZPOOL_CONFIG_REMOVAL_STATS, (uint64_t *)&prs, 417 sizeof (prs) / sizeof (uint64_t)); 418 } 419 420 pool_checkpoint_stat_t pcs; 421 if (spa_checkpoint_get_stats(spa, &pcs) == 0) { 422 fnvlist_add_uint64_array(nvl, 423 ZPOOL_CONFIG_CHECKPOINT_STATS, (uint64_t *)&pcs, 424 sizeof (pcs) / sizeof (uint64_t)); 425 } 426 } 427 428 static void 429 top_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl) 430 { 431 if (vd == vd->vdev_top) { 432 vdev_rebuild_stat_t vrs; 433 if (vdev_rebuild_get_stats(vd, &vrs) == 0) { 434 fnvlist_add_uint64_array(nvl, 435 ZPOOL_CONFIG_REBUILD_STATS, (uint64_t *)&vrs, 436 sizeof (vrs) / sizeof (uint64_t)); 437 } 438 } 439 } 440 441 /* 442 * Generate the nvlist representing this vdev's config. 443 */ 444 nvlist_t * 445 vdev_config_generate(spa_t *spa, vdev_t *vd, boolean_t getstats, 446 vdev_config_flag_t flags) 447 { 448 nvlist_t *nv = NULL; 449 vdev_indirect_config_t *vic = &vd->vdev_indirect_config; 450 451 nv = fnvlist_alloc(); 452 453 fnvlist_add_string(nv, ZPOOL_CONFIG_TYPE, vd->vdev_ops->vdev_op_type); 454 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE))) 455 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ID, vd->vdev_id); 456 fnvlist_add_uint64(nv, ZPOOL_CONFIG_GUID, vd->vdev_guid); 457 458 if (vd->vdev_path != NULL) 459 fnvlist_add_string(nv, ZPOOL_CONFIG_PATH, vd->vdev_path); 460 461 if (vd->vdev_devid != NULL) 462 fnvlist_add_string(nv, ZPOOL_CONFIG_DEVID, vd->vdev_devid); 463 464 if (vd->vdev_physpath != NULL) 465 fnvlist_add_string(nv, ZPOOL_CONFIG_PHYS_PATH, 466 vd->vdev_physpath); 467 468 if (vd->vdev_enc_sysfs_path != NULL) 469 fnvlist_add_string(nv, ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH, 470 vd->vdev_enc_sysfs_path); 471 472 if (vd->vdev_fru != NULL) 473 fnvlist_add_string(nv, ZPOOL_CONFIG_FRU, vd->vdev_fru); 474 475 if (vd->vdev_ops->vdev_op_config_generate != NULL) 476 vd->vdev_ops->vdev_op_config_generate(vd, nv); 477 478 if (vd->vdev_wholedisk != -1ULL) { 479 fnvlist_add_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK, 480 vd->vdev_wholedisk); 481 } 482 483 if (vd->vdev_not_present && !(flags & VDEV_CONFIG_MISSING)) 484 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NOT_PRESENT, 1); 485 486 if (vd->vdev_isspare) 487 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_SPARE, 1); 488 489 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE)) && 490 vd == vd->vdev_top) { 491 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_ARRAY, 492 vd->vdev_ms_array); 493 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_SHIFT, 494 vd->vdev_ms_shift); 495 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASHIFT, vd->vdev_ashift); 496 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASIZE, 497 vd->vdev_asize); 498 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_LOG, vd->vdev_islog); 499 if (vd->vdev_noalloc) { 500 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NONALLOCATING, 501 vd->vdev_noalloc); 502 } 503 504 /* 505 * Slog devices are removed synchronously so don't 506 * persist the vdev_removing flag to the label. 507 */ 508 if (vd->vdev_removing && !vd->vdev_islog) { 509 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVING, 510 vd->vdev_removing); 511 } 512 513 /* zpool command expects alloc class data */ 514 if (getstats && vd->vdev_alloc_bias != VDEV_BIAS_NONE) { 515 const char *bias = NULL; 516 517 switch (vd->vdev_alloc_bias) { 518 case VDEV_BIAS_LOG: 519 bias = VDEV_ALLOC_BIAS_LOG; 520 break; 521 case VDEV_BIAS_SPECIAL: 522 bias = VDEV_ALLOC_BIAS_SPECIAL; 523 break; 524 case VDEV_BIAS_DEDUP: 525 bias = VDEV_ALLOC_BIAS_DEDUP; 526 break; 527 default: 528 ASSERT3U(vd->vdev_alloc_bias, ==, 529 VDEV_BIAS_NONE); 530 } 531 fnvlist_add_string(nv, ZPOOL_CONFIG_ALLOCATION_BIAS, 532 bias); 533 } 534 } 535 536 if (vd->vdev_dtl_sm != NULL) { 537 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DTL, 538 space_map_object(vd->vdev_dtl_sm)); 539 } 540 541 if (vic->vic_mapping_object != 0) { 542 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_OBJECT, 543 vic->vic_mapping_object); 544 } 545 546 if (vic->vic_births_object != 0) { 547 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_BIRTHS, 548 vic->vic_births_object); 549 } 550 551 if (vic->vic_prev_indirect_vdev != UINT64_MAX) { 552 fnvlist_add_uint64(nv, ZPOOL_CONFIG_PREV_INDIRECT_VDEV, 553 vic->vic_prev_indirect_vdev); 554 } 555 556 if (vd->vdev_crtxg) 557 fnvlist_add_uint64(nv, ZPOOL_CONFIG_CREATE_TXG, vd->vdev_crtxg); 558 559 if (vd->vdev_expansion_time) 560 fnvlist_add_uint64(nv, ZPOOL_CONFIG_EXPANSION_TIME, 561 vd->vdev_expansion_time); 562 563 if (flags & VDEV_CONFIG_MOS) { 564 if (vd->vdev_leaf_zap != 0) { 565 ASSERT(vd->vdev_ops->vdev_op_leaf); 566 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_LEAF_ZAP, 567 vd->vdev_leaf_zap); 568 } 569 570 if (vd->vdev_top_zap != 0) { 571 ASSERT(vd == vd->vdev_top); 572 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_TOP_ZAP, 573 vd->vdev_top_zap); 574 } 575 576 if (vd->vdev_ops == &vdev_root_ops && vd->vdev_root_zap != 0 && 577 spa_feature_is_active(vd->vdev_spa, SPA_FEATURE_AVZ_V2)) { 578 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_ROOT_ZAP, 579 vd->vdev_root_zap); 580 } 581 582 if (vd->vdev_resilver_deferred) { 583 ASSERT(vd->vdev_ops->vdev_op_leaf); 584 ASSERT(spa->spa_resilver_deferred); 585 fnvlist_add_boolean(nv, ZPOOL_CONFIG_RESILVER_DEFER); 586 } 587 } 588 589 if (getstats) { 590 vdev_config_generate_stats(vd, nv); 591 592 root_vdev_actions_getprogress(vd, nv); 593 top_vdev_actions_getprogress(vd, nv); 594 595 /* 596 * Note: this can be called from open context 597 * (spa_get_stats()), so we need the rwlock to prevent 598 * the mapping from being changed by condensing. 599 */ 600 rw_enter(&vd->vdev_indirect_rwlock, RW_READER); 601 if (vd->vdev_indirect_mapping != NULL) { 602 ASSERT(vd->vdev_indirect_births != NULL); 603 vdev_indirect_mapping_t *vim = 604 vd->vdev_indirect_mapping; 605 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE, 606 vdev_indirect_mapping_size(vim)); 607 } 608 rw_exit(&vd->vdev_indirect_rwlock); 609 if (vd->vdev_mg != NULL && 610 vd->vdev_mg->mg_fragmentation != ZFS_FRAG_INVALID) { 611 /* 612 * Compute approximately how much memory would be used 613 * for the indirect mapping if this device were to 614 * be removed. 615 * 616 * Note: If the frag metric is invalid, then not 617 * enough metaslabs have been converted to have 618 * histograms. 619 */ 620 uint64_t seg_count = 0; 621 uint64_t to_alloc = vd->vdev_stat.vs_alloc; 622 623 /* 624 * There are the same number of allocated segments 625 * as free segments, so we will have at least one 626 * entry per free segment. However, small free 627 * segments (smaller than vdev_removal_max_span) 628 * will be combined with adjacent allocated segments 629 * as a single mapping. 630 */ 631 for (int i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) { 632 if (i + 1 < highbit64(vdev_removal_max_span) 633 - 1) { 634 to_alloc += 635 vd->vdev_mg->mg_histogram[i] << 636 (i + 1); 637 } else { 638 seg_count += 639 vd->vdev_mg->mg_histogram[i]; 640 } 641 } 642 643 /* 644 * The maximum length of a mapping is 645 * zfs_remove_max_segment, so we need at least one entry 646 * per zfs_remove_max_segment of allocated data. 647 */ 648 seg_count += to_alloc / spa_remove_max_segment(spa); 649 650 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE, 651 seg_count * 652 sizeof (vdev_indirect_mapping_entry_phys_t)); 653 } 654 } 655 656 if (!vd->vdev_ops->vdev_op_leaf) { 657 nvlist_t **child; 658 uint64_t c; 659 660 ASSERT(!vd->vdev_ishole); 661 662 child = kmem_alloc(vd->vdev_children * sizeof (nvlist_t *), 663 KM_SLEEP); 664 665 for (c = 0; c < vd->vdev_children; c++) { 666 child[c] = vdev_config_generate(spa, vd->vdev_child[c], 667 getstats, flags); 668 } 669 670 fnvlist_add_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN, 671 (const nvlist_t * const *)child, vd->vdev_children); 672 673 for (c = 0; c < vd->vdev_children; c++) 674 nvlist_free(child[c]); 675 676 kmem_free(child, vd->vdev_children * sizeof (nvlist_t *)); 677 678 } else { 679 const char *aux = NULL; 680 681 if (vd->vdev_offline && !vd->vdev_tmpoffline) 682 fnvlist_add_uint64(nv, ZPOOL_CONFIG_OFFLINE, B_TRUE); 683 if (vd->vdev_resilver_txg != 0) 684 fnvlist_add_uint64(nv, ZPOOL_CONFIG_RESILVER_TXG, 685 vd->vdev_resilver_txg); 686 if (vd->vdev_rebuild_txg != 0) 687 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REBUILD_TXG, 688 vd->vdev_rebuild_txg); 689 if (vd->vdev_faulted) 690 fnvlist_add_uint64(nv, ZPOOL_CONFIG_FAULTED, B_TRUE); 691 if (vd->vdev_degraded) 692 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DEGRADED, B_TRUE); 693 if (vd->vdev_removed) 694 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVED, B_TRUE); 695 if (vd->vdev_unspare) 696 fnvlist_add_uint64(nv, ZPOOL_CONFIG_UNSPARE, B_TRUE); 697 if (vd->vdev_ishole) 698 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_HOLE, B_TRUE); 699 700 /* Set the reason why we're FAULTED/DEGRADED. */ 701 switch (vd->vdev_stat.vs_aux) { 702 case VDEV_AUX_ERR_EXCEEDED: 703 aux = "err_exceeded"; 704 break; 705 706 case VDEV_AUX_EXTERNAL: 707 aux = "external"; 708 break; 709 } 710 711 if (aux != NULL && !vd->vdev_tmpoffline) { 712 fnvlist_add_string(nv, ZPOOL_CONFIG_AUX_STATE, aux); 713 } else { 714 /* 715 * We're healthy - clear any previous AUX_STATE values. 716 */ 717 if (nvlist_exists(nv, ZPOOL_CONFIG_AUX_STATE)) 718 nvlist_remove_all(nv, ZPOOL_CONFIG_AUX_STATE); 719 } 720 721 if (vd->vdev_splitting && vd->vdev_orig_guid != 0LL) { 722 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ORIG_GUID, 723 vd->vdev_orig_guid); 724 } 725 } 726 727 return (nv); 728 } 729 730 /* 731 * Generate a view of the top-level vdevs. If we currently have holes 732 * in the namespace, then generate an array which contains a list of holey 733 * vdevs. Additionally, add the number of top-level children that currently 734 * exist. 735 */ 736 void 737 vdev_top_config_generate(spa_t *spa, nvlist_t *config) 738 { 739 vdev_t *rvd = spa->spa_root_vdev; 740 uint64_t *array; 741 uint_t c, idx; 742 743 array = kmem_alloc(rvd->vdev_children * sizeof (uint64_t), KM_SLEEP); 744 745 for (c = 0, idx = 0; c < rvd->vdev_children; c++) { 746 vdev_t *tvd = rvd->vdev_child[c]; 747 748 if (tvd->vdev_ishole) { 749 array[idx++] = c; 750 } 751 } 752 753 if (idx) { 754 VERIFY(nvlist_add_uint64_array(config, ZPOOL_CONFIG_HOLE_ARRAY, 755 array, idx) == 0); 756 } 757 758 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN, 759 rvd->vdev_children) == 0); 760 761 kmem_free(array, rvd->vdev_children * sizeof (uint64_t)); 762 } 763 764 /* 765 * Returns the configuration from the label of the given vdev. For vdevs 766 * which don't have a txg value stored on their label (i.e. spares/cache) 767 * or have not been completely initialized (txg = 0) just return 768 * the configuration from the first valid label we find. Otherwise, 769 * find the most up-to-date label that does not exceed the specified 770 * 'txg' value. 771 */ 772 nvlist_t * 773 vdev_label_read_config(vdev_t *vd, uint64_t txg) 774 { 775 spa_t *spa = vd->vdev_spa; 776 nvlist_t *config = NULL; 777 vdev_phys_t *vp[VDEV_LABELS]; 778 abd_t *vp_abd[VDEV_LABELS]; 779 zio_t *zio[VDEV_LABELS]; 780 uint64_t best_txg = 0; 781 uint64_t label_txg = 0; 782 int error = 0; 783 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 784 ZIO_FLAG_SPECULATIVE; 785 786 ASSERT(vd->vdev_validate_thread == curthread || 787 spa_config_held(spa, SCL_STATE_ALL, RW_WRITER) == SCL_STATE_ALL); 788 789 if (!vdev_readable(vd)) 790 return (NULL); 791 792 /* 793 * The label for a dRAID distributed spare is not stored on disk. 794 * Instead it is generated when needed which allows us to bypass 795 * the pipeline when reading the config from the label. 796 */ 797 if (vd->vdev_ops == &vdev_draid_spare_ops) 798 return (vdev_draid_read_config_spare(vd)); 799 800 for (int l = 0; l < VDEV_LABELS; l++) { 801 vp_abd[l] = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 802 vp[l] = abd_to_buf(vp_abd[l]); 803 } 804 805 retry: 806 for (int l = 0; l < VDEV_LABELS; l++) { 807 zio[l] = zio_root(spa, NULL, NULL, flags); 808 809 vdev_label_read(zio[l], vd, l, vp_abd[l], 810 offsetof(vdev_label_t, vl_vdev_phys), sizeof (vdev_phys_t), 811 NULL, NULL, flags); 812 } 813 for (int l = 0; l < VDEV_LABELS; l++) { 814 nvlist_t *label = NULL; 815 816 if (zio_wait(zio[l]) == 0 && 817 nvlist_unpack(vp[l]->vp_nvlist, sizeof (vp[l]->vp_nvlist), 818 &label, 0) == 0) { 819 /* 820 * Auxiliary vdevs won't have txg values in their 821 * labels and newly added vdevs may not have been 822 * completely initialized so just return the 823 * configuration from the first valid label we 824 * encounter. 825 */ 826 error = nvlist_lookup_uint64(label, 827 ZPOOL_CONFIG_POOL_TXG, &label_txg); 828 if ((error || label_txg == 0) && !config) { 829 config = label; 830 for (l++; l < VDEV_LABELS; l++) 831 zio_wait(zio[l]); 832 break; 833 } else if (label_txg <= txg && label_txg > best_txg) { 834 best_txg = label_txg; 835 nvlist_free(config); 836 config = fnvlist_dup(label); 837 } 838 } 839 840 if (label != NULL) { 841 nvlist_free(label); 842 label = NULL; 843 } 844 } 845 846 if (config == NULL && !(flags & ZIO_FLAG_TRYHARD)) { 847 flags |= ZIO_FLAG_TRYHARD; 848 goto retry; 849 } 850 851 /* 852 * We found a valid label but it didn't pass txg restrictions. 853 */ 854 if (config == NULL && label_txg != 0) { 855 vdev_dbgmsg(vd, "label discarded as txg is too large " 856 "(%llu > %llu)", (u_longlong_t)label_txg, 857 (u_longlong_t)txg); 858 } 859 860 for (int l = 0; l < VDEV_LABELS; l++) { 861 abd_free(vp_abd[l]); 862 } 863 864 return (config); 865 } 866 867 /* 868 * Determine if a device is in use. The 'spare_guid' parameter will be filled 869 * in with the device guid if this spare is active elsewhere on the system. 870 */ 871 static boolean_t 872 vdev_inuse(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason, 873 uint64_t *spare_guid, uint64_t *l2cache_guid) 874 { 875 spa_t *spa = vd->vdev_spa; 876 uint64_t state, pool_guid, device_guid, txg, spare_pool; 877 uint64_t vdtxg = 0; 878 nvlist_t *label; 879 880 if (spare_guid) 881 *spare_guid = 0ULL; 882 if (l2cache_guid) 883 *l2cache_guid = 0ULL; 884 885 /* 886 * Read the label, if any, and perform some basic sanity checks. 887 */ 888 if ((label = vdev_label_read_config(vd, -1ULL)) == NULL) 889 return (B_FALSE); 890 891 (void) nvlist_lookup_uint64(label, ZPOOL_CONFIG_CREATE_TXG, 892 &vdtxg); 893 894 if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_STATE, 895 &state) != 0 || 896 nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID, 897 &device_guid) != 0) { 898 nvlist_free(label); 899 return (B_FALSE); 900 } 901 902 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 903 (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID, 904 &pool_guid) != 0 || 905 nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG, 906 &txg) != 0)) { 907 nvlist_free(label); 908 return (B_FALSE); 909 } 910 911 nvlist_free(label); 912 913 /* 914 * Check to see if this device indeed belongs to the pool it claims to 915 * be a part of. The only way this is allowed is if the device is a hot 916 * spare (which we check for later on). 917 */ 918 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 919 !spa_guid_exists(pool_guid, device_guid) && 920 !spa_spare_exists(device_guid, NULL, NULL) && 921 !spa_l2cache_exists(device_guid, NULL)) 922 return (B_FALSE); 923 924 /* 925 * If the transaction group is zero, then this an initialized (but 926 * unused) label. This is only an error if the create transaction 927 * on-disk is the same as the one we're using now, in which case the 928 * user has attempted to add the same vdev multiple times in the same 929 * transaction. 930 */ 931 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 932 txg == 0 && vdtxg == crtxg) 933 return (B_TRUE); 934 935 /* 936 * Check to see if this is a spare device. We do an explicit check for 937 * spa_has_spare() here because it may be on our pending list of spares 938 * to add. 939 */ 940 if (spa_spare_exists(device_guid, &spare_pool, NULL) || 941 spa_has_spare(spa, device_guid)) { 942 if (spare_guid) 943 *spare_guid = device_guid; 944 945 switch (reason) { 946 case VDEV_LABEL_CREATE: 947 return (B_TRUE); 948 949 case VDEV_LABEL_REPLACE: 950 return (!spa_has_spare(spa, device_guid) || 951 spare_pool != 0ULL); 952 953 case VDEV_LABEL_SPARE: 954 return (spa_has_spare(spa, device_guid)); 955 default: 956 break; 957 } 958 } 959 960 /* 961 * Check to see if this is an l2cache device. 962 */ 963 if (spa_l2cache_exists(device_guid, NULL) || 964 spa_has_l2cache(spa, device_guid)) { 965 if (l2cache_guid) 966 *l2cache_guid = device_guid; 967 968 switch (reason) { 969 case VDEV_LABEL_CREATE: 970 return (B_TRUE); 971 972 case VDEV_LABEL_REPLACE: 973 return (!spa_has_l2cache(spa, device_guid)); 974 975 case VDEV_LABEL_L2CACHE: 976 return (spa_has_l2cache(spa, device_guid)); 977 default: 978 break; 979 } 980 } 981 982 /* 983 * We can't rely on a pool's state if it's been imported 984 * read-only. Instead we look to see if the pools is marked 985 * read-only in the namespace and set the state to active. 986 */ 987 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 988 (spa = spa_by_guid(pool_guid, device_guid)) != NULL && 989 spa_mode(spa) == SPA_MODE_READ) 990 state = POOL_STATE_ACTIVE; 991 992 /* 993 * If the device is marked ACTIVE, then this device is in use by another 994 * pool on the system. 995 */ 996 return (state == POOL_STATE_ACTIVE); 997 } 998 999 /* 1000 * Initialize a vdev label. We check to make sure each leaf device is not in 1001 * use, and writable. We put down an initial label which we will later 1002 * overwrite with a complete label. Note that it's important to do this 1003 * sequentially, not in parallel, so that we catch cases of multiple use of the 1004 * same leaf vdev in the vdev we're creating -- e.g. mirroring a disk with 1005 * itself. 1006 */ 1007 int 1008 vdev_label_init(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason) 1009 { 1010 spa_t *spa = vd->vdev_spa; 1011 nvlist_t *label; 1012 vdev_phys_t *vp; 1013 abd_t *vp_abd; 1014 abd_t *bootenv; 1015 uberblock_t *ub; 1016 abd_t *ub_abd; 1017 zio_t *zio; 1018 char *buf; 1019 size_t buflen; 1020 int error; 1021 uint64_t spare_guid = 0, l2cache_guid = 0; 1022 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; 1023 1024 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); 1025 1026 for (int c = 0; c < vd->vdev_children; c++) 1027 if ((error = vdev_label_init(vd->vdev_child[c], 1028 crtxg, reason)) != 0) 1029 return (error); 1030 1031 /* Track the creation time for this vdev */ 1032 vd->vdev_crtxg = crtxg; 1033 1034 if (!vd->vdev_ops->vdev_op_leaf || !spa_writeable(spa)) 1035 return (0); 1036 1037 /* 1038 * Dead vdevs cannot be initialized. 1039 */ 1040 if (vdev_is_dead(vd)) 1041 return (SET_ERROR(EIO)); 1042 1043 /* 1044 * Determine if the vdev is in use. 1045 */ 1046 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPLIT && 1047 vdev_inuse(vd, crtxg, reason, &spare_guid, &l2cache_guid)) 1048 return (SET_ERROR(EBUSY)); 1049 1050 /* 1051 * If this is a request to add or replace a spare or l2cache device 1052 * that is in use elsewhere on the system, then we must update the 1053 * guid (which was initialized to a random value) to reflect the 1054 * actual GUID (which is shared between multiple pools). 1055 */ 1056 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_L2CACHE && 1057 spare_guid != 0ULL) { 1058 uint64_t guid_delta = spare_guid - vd->vdev_guid; 1059 1060 vd->vdev_guid += guid_delta; 1061 1062 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent) 1063 pvd->vdev_guid_sum += guid_delta; 1064 1065 /* 1066 * If this is a replacement, then we want to fallthrough to the 1067 * rest of the code. If we're adding a spare, then it's already 1068 * labeled appropriately and we can just return. 1069 */ 1070 if (reason == VDEV_LABEL_SPARE) 1071 return (0); 1072 ASSERT(reason == VDEV_LABEL_REPLACE || 1073 reason == VDEV_LABEL_SPLIT); 1074 } 1075 1076 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPARE && 1077 l2cache_guid != 0ULL) { 1078 uint64_t guid_delta = l2cache_guid - vd->vdev_guid; 1079 1080 vd->vdev_guid += guid_delta; 1081 1082 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent) 1083 pvd->vdev_guid_sum += guid_delta; 1084 1085 /* 1086 * If this is a replacement, then we want to fallthrough to the 1087 * rest of the code. If we're adding an l2cache, then it's 1088 * already labeled appropriately and we can just return. 1089 */ 1090 if (reason == VDEV_LABEL_L2CACHE) 1091 return (0); 1092 ASSERT(reason == VDEV_LABEL_REPLACE); 1093 } 1094 1095 /* 1096 * Initialize its label. 1097 */ 1098 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 1099 abd_zero(vp_abd, sizeof (vdev_phys_t)); 1100 vp = abd_to_buf(vp_abd); 1101 1102 /* 1103 * Generate a label describing the pool and our top-level vdev. 1104 * We mark it as being from txg 0 to indicate that it's not 1105 * really part of an active pool just yet. The labels will 1106 * be written again with a meaningful txg by spa_sync(). 1107 */ 1108 if (reason == VDEV_LABEL_SPARE || 1109 (reason == VDEV_LABEL_REMOVE && vd->vdev_isspare)) { 1110 /* 1111 * For inactive hot spares, we generate a special label that 1112 * identifies as a mutually shared hot spare. We write the 1113 * label if we are adding a hot spare, or if we are removing an 1114 * active hot spare (in which case we want to revert the 1115 * labels). 1116 */ 1117 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1118 1119 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION, 1120 spa_version(spa)) == 0); 1121 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE, 1122 POOL_STATE_SPARE) == 0); 1123 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID, 1124 vd->vdev_guid) == 0); 1125 } else if (reason == VDEV_LABEL_L2CACHE || 1126 (reason == VDEV_LABEL_REMOVE && vd->vdev_isl2cache)) { 1127 /* 1128 * For level 2 ARC devices, add a special label. 1129 */ 1130 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1131 1132 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION, 1133 spa_version(spa)) == 0); 1134 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE, 1135 POOL_STATE_L2CACHE) == 0); 1136 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID, 1137 vd->vdev_guid) == 0); 1138 } else { 1139 uint64_t txg = 0ULL; 1140 1141 if (reason == VDEV_LABEL_SPLIT) 1142 txg = spa->spa_uberblock.ub_txg; 1143 label = spa_config_generate(spa, vd, txg, B_FALSE); 1144 1145 /* 1146 * Add our creation time. This allows us to detect multiple 1147 * vdev uses as described above, and automatically expires if we 1148 * fail. 1149 */ 1150 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_CREATE_TXG, 1151 crtxg) == 0); 1152 } 1153 1154 buf = vp->vp_nvlist; 1155 buflen = sizeof (vp->vp_nvlist); 1156 1157 error = nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP); 1158 if (error != 0) { 1159 nvlist_free(label); 1160 abd_free(vp_abd); 1161 /* EFAULT means nvlist_pack ran out of room */ 1162 return (SET_ERROR(error == EFAULT ? ENAMETOOLONG : EINVAL)); 1163 } 1164 1165 /* 1166 * Initialize uberblock template. 1167 */ 1168 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_RING, B_TRUE); 1169 abd_zero(ub_abd, VDEV_UBERBLOCK_RING); 1170 abd_copy_from_buf(ub_abd, &spa->spa_uberblock, sizeof (uberblock_t)); 1171 ub = abd_to_buf(ub_abd); 1172 ub->ub_txg = 0; 1173 1174 /* Initialize the 2nd padding area. */ 1175 bootenv = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE); 1176 abd_zero(bootenv, VDEV_PAD_SIZE); 1177 1178 /* 1179 * Write everything in parallel. 1180 */ 1181 retry: 1182 zio = zio_root(spa, NULL, NULL, flags); 1183 1184 for (int l = 0; l < VDEV_LABELS; l++) { 1185 1186 vdev_label_write(zio, vd, l, vp_abd, 1187 offsetof(vdev_label_t, vl_vdev_phys), 1188 sizeof (vdev_phys_t), NULL, NULL, flags); 1189 1190 /* 1191 * Skip the 1st padding area. 1192 * Zero out the 2nd padding area where it might have 1193 * left over data from previous filesystem format. 1194 */ 1195 vdev_label_write(zio, vd, l, bootenv, 1196 offsetof(vdev_label_t, vl_be), 1197 VDEV_PAD_SIZE, NULL, NULL, flags); 1198 1199 vdev_label_write(zio, vd, l, ub_abd, 1200 offsetof(vdev_label_t, vl_uberblock), 1201 VDEV_UBERBLOCK_RING, NULL, NULL, flags); 1202 } 1203 1204 error = zio_wait(zio); 1205 1206 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) { 1207 flags |= ZIO_FLAG_TRYHARD; 1208 goto retry; 1209 } 1210 1211 nvlist_free(label); 1212 abd_free(bootenv); 1213 abd_free(ub_abd); 1214 abd_free(vp_abd); 1215 1216 /* 1217 * If this vdev hasn't been previously identified as a spare, then we 1218 * mark it as such only if a) we are labeling it as a spare, or b) it 1219 * exists as a spare elsewhere in the system. Do the same for 1220 * level 2 ARC devices. 1221 */ 1222 if (error == 0 && !vd->vdev_isspare && 1223 (reason == VDEV_LABEL_SPARE || 1224 spa_spare_exists(vd->vdev_guid, NULL, NULL))) 1225 spa_spare_add(vd); 1226 1227 if (error == 0 && !vd->vdev_isl2cache && 1228 (reason == VDEV_LABEL_L2CACHE || 1229 spa_l2cache_exists(vd->vdev_guid, NULL))) 1230 spa_l2cache_add(vd); 1231 1232 return (error); 1233 } 1234 1235 /* 1236 * Done callback for vdev_label_read_bootenv_impl. If this is the first 1237 * callback to finish, store our abd in the callback pointer. Otherwise, we 1238 * just free our abd and return. 1239 */ 1240 static void 1241 vdev_label_read_bootenv_done(zio_t *zio) 1242 { 1243 zio_t *rio = zio->io_private; 1244 abd_t **cbp = rio->io_private; 1245 1246 ASSERT3U(zio->io_size, ==, VDEV_PAD_SIZE); 1247 1248 if (zio->io_error == 0) { 1249 mutex_enter(&rio->io_lock); 1250 if (*cbp == NULL) { 1251 /* Will free this buffer in vdev_label_read_bootenv. */ 1252 *cbp = zio->io_abd; 1253 } else { 1254 abd_free(zio->io_abd); 1255 } 1256 mutex_exit(&rio->io_lock); 1257 } else { 1258 abd_free(zio->io_abd); 1259 } 1260 } 1261 1262 static void 1263 vdev_label_read_bootenv_impl(zio_t *zio, vdev_t *vd, int flags) 1264 { 1265 for (int c = 0; c < vd->vdev_children; c++) 1266 vdev_label_read_bootenv_impl(zio, vd->vdev_child[c], flags); 1267 1268 /* 1269 * We just use the first label that has a correct checksum; the 1270 * bootloader should have rewritten them all to be the same on boot, 1271 * and any changes we made since boot have been the same across all 1272 * labels. 1273 */ 1274 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd)) { 1275 for (int l = 0; l < VDEV_LABELS; l++) { 1276 vdev_label_read(zio, vd, l, 1277 abd_alloc_linear(VDEV_PAD_SIZE, B_FALSE), 1278 offsetof(vdev_label_t, vl_be), VDEV_PAD_SIZE, 1279 vdev_label_read_bootenv_done, zio, flags); 1280 } 1281 } 1282 } 1283 1284 int 1285 vdev_label_read_bootenv(vdev_t *rvd, nvlist_t *bootenv) 1286 { 1287 nvlist_t *config; 1288 spa_t *spa = rvd->vdev_spa; 1289 abd_t *abd = NULL; 1290 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 1291 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD; 1292 1293 ASSERT(bootenv); 1294 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); 1295 1296 zio_t *zio = zio_root(spa, NULL, &abd, flags); 1297 vdev_label_read_bootenv_impl(zio, rvd, flags); 1298 int err = zio_wait(zio); 1299 1300 if (abd != NULL) { 1301 char *buf; 1302 vdev_boot_envblock_t *vbe = abd_to_buf(abd); 1303 1304 vbe->vbe_version = ntohll(vbe->vbe_version); 1305 switch (vbe->vbe_version) { 1306 case VB_RAW: 1307 /* 1308 * if we have textual data in vbe_bootenv, create nvlist 1309 * with key "envmap". 1310 */ 1311 fnvlist_add_uint64(bootenv, BOOTENV_VERSION, VB_RAW); 1312 vbe->vbe_bootenv[sizeof (vbe->vbe_bootenv) - 1] = '\0'; 1313 fnvlist_add_string(bootenv, GRUB_ENVMAP, 1314 vbe->vbe_bootenv); 1315 break; 1316 1317 case VB_NVLIST: 1318 err = nvlist_unpack(vbe->vbe_bootenv, 1319 sizeof (vbe->vbe_bootenv), &config, 0); 1320 if (err == 0) { 1321 fnvlist_merge(bootenv, config); 1322 nvlist_free(config); 1323 break; 1324 } 1325 zfs_fallthrough; 1326 default: 1327 /* Check for FreeBSD zfs bootonce command string */ 1328 buf = abd_to_buf(abd); 1329 if (*buf == '\0') { 1330 fnvlist_add_uint64(bootenv, BOOTENV_VERSION, 1331 VB_NVLIST); 1332 break; 1333 } 1334 fnvlist_add_string(bootenv, FREEBSD_BOOTONCE, buf); 1335 } 1336 1337 /* 1338 * abd was allocated in vdev_label_read_bootenv_impl() 1339 */ 1340 abd_free(abd); 1341 /* 1342 * If we managed to read any successfully, 1343 * return success. 1344 */ 1345 return (0); 1346 } 1347 return (err); 1348 } 1349 1350 int 1351 vdev_label_write_bootenv(vdev_t *vd, nvlist_t *env) 1352 { 1353 zio_t *zio; 1354 spa_t *spa = vd->vdev_spa; 1355 vdev_boot_envblock_t *bootenv; 1356 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; 1357 int error; 1358 size_t nvsize; 1359 char *nvbuf; 1360 const char *tmp; 1361 1362 error = nvlist_size(env, &nvsize, NV_ENCODE_XDR); 1363 if (error != 0) 1364 return (SET_ERROR(error)); 1365 1366 if (nvsize >= sizeof (bootenv->vbe_bootenv)) { 1367 return (SET_ERROR(E2BIG)); 1368 } 1369 1370 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); 1371 1372 error = ENXIO; 1373 for (int c = 0; c < vd->vdev_children; c++) { 1374 int child_err; 1375 1376 child_err = vdev_label_write_bootenv(vd->vdev_child[c], env); 1377 /* 1378 * As long as any of the disks managed to write all of their 1379 * labels successfully, return success. 1380 */ 1381 if (child_err == 0) 1382 error = child_err; 1383 } 1384 1385 if (!vd->vdev_ops->vdev_op_leaf || vdev_is_dead(vd) || 1386 !vdev_writeable(vd)) { 1387 return (error); 1388 } 1389 ASSERT3U(sizeof (*bootenv), ==, VDEV_PAD_SIZE); 1390 abd_t *abd = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE); 1391 abd_zero(abd, VDEV_PAD_SIZE); 1392 1393 bootenv = abd_borrow_buf_copy(abd, VDEV_PAD_SIZE); 1394 nvbuf = bootenv->vbe_bootenv; 1395 nvsize = sizeof (bootenv->vbe_bootenv); 1396 1397 bootenv->vbe_version = fnvlist_lookup_uint64(env, BOOTENV_VERSION); 1398 switch (bootenv->vbe_version) { 1399 case VB_RAW: 1400 if (nvlist_lookup_string(env, GRUB_ENVMAP, &tmp) == 0) { 1401 (void) strlcpy(bootenv->vbe_bootenv, tmp, nvsize); 1402 } 1403 error = 0; 1404 break; 1405 1406 case VB_NVLIST: 1407 error = nvlist_pack(env, &nvbuf, &nvsize, NV_ENCODE_XDR, 1408 KM_SLEEP); 1409 break; 1410 1411 default: 1412 error = EINVAL; 1413 break; 1414 } 1415 1416 if (error == 0) { 1417 bootenv->vbe_version = htonll(bootenv->vbe_version); 1418 abd_return_buf_copy(abd, bootenv, VDEV_PAD_SIZE); 1419 } else { 1420 abd_free(abd); 1421 return (SET_ERROR(error)); 1422 } 1423 1424 retry: 1425 zio = zio_root(spa, NULL, NULL, flags); 1426 for (int l = 0; l < VDEV_LABELS; l++) { 1427 vdev_label_write(zio, vd, l, abd, 1428 offsetof(vdev_label_t, vl_be), 1429 VDEV_PAD_SIZE, NULL, NULL, flags); 1430 } 1431 1432 error = zio_wait(zio); 1433 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) { 1434 flags |= ZIO_FLAG_TRYHARD; 1435 goto retry; 1436 } 1437 1438 abd_free(abd); 1439 return (error); 1440 } 1441 1442 /* 1443 * ========================================================================== 1444 * uberblock load/sync 1445 * ========================================================================== 1446 */ 1447 1448 /* 1449 * Consider the following situation: txg is safely synced to disk. We've 1450 * written the first uberblock for txg + 1, and then we lose power. When we 1451 * come back up, we fail to see the uberblock for txg + 1 because, say, 1452 * it was on a mirrored device and the replica to which we wrote txg + 1 1453 * is now offline. If we then make some changes and sync txg + 1, and then 1454 * the missing replica comes back, then for a few seconds we'll have two 1455 * conflicting uberblocks on disk with the same txg. The solution is simple: 1456 * among uberblocks with equal txg, choose the one with the latest timestamp. 1457 */ 1458 static int 1459 vdev_uberblock_compare(const uberblock_t *ub1, const uberblock_t *ub2) 1460 { 1461 int cmp = TREE_CMP(ub1->ub_txg, ub2->ub_txg); 1462 1463 if (likely(cmp)) 1464 return (cmp); 1465 1466 cmp = TREE_CMP(ub1->ub_timestamp, ub2->ub_timestamp); 1467 if (likely(cmp)) 1468 return (cmp); 1469 1470 /* 1471 * If MMP_VALID(ub) && MMP_SEQ_VALID(ub) then the host has an MMP-aware 1472 * ZFS, e.g. OpenZFS >= 0.7. 1473 * 1474 * If one ub has MMP and the other does not, they were written by 1475 * different hosts, which matters for MMP. So we treat no MMP/no SEQ as 1476 * a 0 value. 1477 * 1478 * Since timestamp and txg are the same if we get this far, either is 1479 * acceptable for importing the pool. 1480 */ 1481 unsigned int seq1 = 0; 1482 unsigned int seq2 = 0; 1483 1484 if (MMP_VALID(ub1) && MMP_SEQ_VALID(ub1)) 1485 seq1 = MMP_SEQ(ub1); 1486 1487 if (MMP_VALID(ub2) && MMP_SEQ_VALID(ub2)) 1488 seq2 = MMP_SEQ(ub2); 1489 1490 return (TREE_CMP(seq1, seq2)); 1491 } 1492 1493 struct ubl_cbdata { 1494 uberblock_t *ubl_ubbest; /* Best uberblock */ 1495 vdev_t *ubl_vd; /* vdev associated with the above */ 1496 }; 1497 1498 static void 1499 vdev_uberblock_load_done(zio_t *zio) 1500 { 1501 vdev_t *vd = zio->io_vd; 1502 spa_t *spa = zio->io_spa; 1503 zio_t *rio = zio->io_private; 1504 uberblock_t *ub = abd_to_buf(zio->io_abd); 1505 struct ubl_cbdata *cbp = rio->io_private; 1506 1507 ASSERT3U(zio->io_size, ==, VDEV_UBERBLOCK_SIZE(vd)); 1508 1509 if (zio->io_error == 0 && uberblock_verify(ub) == 0) { 1510 mutex_enter(&rio->io_lock); 1511 if (ub->ub_txg <= spa->spa_load_max_txg && 1512 vdev_uberblock_compare(ub, cbp->ubl_ubbest) > 0) { 1513 /* 1514 * Keep track of the vdev in which this uberblock 1515 * was found. We will use this information later 1516 * to obtain the config nvlist associated with 1517 * this uberblock. 1518 */ 1519 *cbp->ubl_ubbest = *ub; 1520 cbp->ubl_vd = vd; 1521 } 1522 mutex_exit(&rio->io_lock); 1523 } 1524 1525 abd_free(zio->io_abd); 1526 } 1527 1528 static void 1529 vdev_uberblock_load_impl(zio_t *zio, vdev_t *vd, int flags, 1530 struct ubl_cbdata *cbp) 1531 { 1532 for (int c = 0; c < vd->vdev_children; c++) 1533 vdev_uberblock_load_impl(zio, vd->vdev_child[c], flags, cbp); 1534 1535 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd) && 1536 vd->vdev_ops != &vdev_draid_spare_ops) { 1537 for (int l = 0; l < VDEV_LABELS; l++) { 1538 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) { 1539 vdev_label_read(zio, vd, l, 1540 abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), 1541 B_TRUE), VDEV_UBERBLOCK_OFFSET(vd, n), 1542 VDEV_UBERBLOCK_SIZE(vd), 1543 vdev_uberblock_load_done, zio, flags); 1544 } 1545 } 1546 } 1547 } 1548 1549 /* 1550 * Reads the 'best' uberblock from disk along with its associated 1551 * configuration. First, we read the uberblock array of each label of each 1552 * vdev, keeping track of the uberblock with the highest txg in each array. 1553 * Then, we read the configuration from the same vdev as the best uberblock. 1554 */ 1555 void 1556 vdev_uberblock_load(vdev_t *rvd, uberblock_t *ub, nvlist_t **config) 1557 { 1558 zio_t *zio; 1559 spa_t *spa = rvd->vdev_spa; 1560 struct ubl_cbdata cb; 1561 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 1562 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD; 1563 1564 ASSERT(ub); 1565 ASSERT(config); 1566 1567 memset(ub, 0, sizeof (uberblock_t)); 1568 *config = NULL; 1569 1570 cb.ubl_ubbest = ub; 1571 cb.ubl_vd = NULL; 1572 1573 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 1574 zio = zio_root(spa, NULL, &cb, flags); 1575 vdev_uberblock_load_impl(zio, rvd, flags, &cb); 1576 (void) zio_wait(zio); 1577 1578 /* 1579 * It's possible that the best uberblock was discovered on a label 1580 * that has a configuration which was written in a future txg. 1581 * Search all labels on this vdev to find the configuration that 1582 * matches the txg for our uberblock. 1583 */ 1584 if (cb.ubl_vd != NULL) { 1585 vdev_dbgmsg(cb.ubl_vd, "best uberblock found for spa %s. " 1586 "txg %llu", spa->spa_name, (u_longlong_t)ub->ub_txg); 1587 1588 *config = vdev_label_read_config(cb.ubl_vd, ub->ub_txg); 1589 if (*config == NULL && spa->spa_extreme_rewind) { 1590 vdev_dbgmsg(cb.ubl_vd, "failed to read label config. " 1591 "Trying again without txg restrictions."); 1592 *config = vdev_label_read_config(cb.ubl_vd, UINT64_MAX); 1593 } 1594 if (*config == NULL) { 1595 vdev_dbgmsg(cb.ubl_vd, "failed to read label config"); 1596 } 1597 } 1598 spa_config_exit(spa, SCL_ALL, FTAG); 1599 } 1600 1601 /* 1602 * For use when a leaf vdev is expanded. 1603 * The location of labels 2 and 3 changed, and at the new location the 1604 * uberblock rings are either empty or contain garbage. The sync will write 1605 * new configs there because the vdev is dirty, but expansion also needs the 1606 * uberblock rings copied. Read them from label 0 which did not move. 1607 * 1608 * Since the point is to populate labels {2,3} with valid uberblocks, 1609 * we zero uberblocks we fail to read or which are not valid. 1610 */ 1611 1612 static void 1613 vdev_copy_uberblocks(vdev_t *vd) 1614 { 1615 abd_t *ub_abd; 1616 zio_t *write_zio; 1617 int locks = (SCL_L2ARC | SCL_ZIO); 1618 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 1619 ZIO_FLAG_SPECULATIVE; 1620 1621 ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_READER) == 1622 SCL_STATE); 1623 ASSERT(vd->vdev_ops->vdev_op_leaf); 1624 1625 /* 1626 * No uberblocks are stored on distributed spares, they may be 1627 * safely skipped when expanding a leaf vdev. 1628 */ 1629 if (vd->vdev_ops == &vdev_draid_spare_ops) 1630 return; 1631 1632 spa_config_enter(vd->vdev_spa, locks, FTAG, RW_READER); 1633 1634 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), B_TRUE); 1635 1636 write_zio = zio_root(vd->vdev_spa, NULL, NULL, flags); 1637 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) { 1638 const int src_label = 0; 1639 zio_t *zio; 1640 1641 zio = zio_root(vd->vdev_spa, NULL, NULL, flags); 1642 vdev_label_read(zio, vd, src_label, ub_abd, 1643 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd), 1644 NULL, NULL, flags); 1645 1646 if (zio_wait(zio) || uberblock_verify(abd_to_buf(ub_abd))) 1647 abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd)); 1648 1649 for (int l = 2; l < VDEV_LABELS; l++) 1650 vdev_label_write(write_zio, vd, l, ub_abd, 1651 VDEV_UBERBLOCK_OFFSET(vd, n), 1652 VDEV_UBERBLOCK_SIZE(vd), NULL, NULL, 1653 flags | ZIO_FLAG_DONT_PROPAGATE); 1654 } 1655 (void) zio_wait(write_zio); 1656 1657 spa_config_exit(vd->vdev_spa, locks, FTAG); 1658 1659 abd_free(ub_abd); 1660 } 1661 1662 /* 1663 * On success, increment root zio's count of good writes. 1664 * We only get credit for writes to known-visible vdevs; see spa_vdev_add(). 1665 */ 1666 static void 1667 vdev_uberblock_sync_done(zio_t *zio) 1668 { 1669 uint64_t *good_writes = zio->io_private; 1670 1671 if (zio->io_error == 0 && zio->io_vd->vdev_top->vdev_ms_array != 0) 1672 atomic_inc_64(good_writes); 1673 } 1674 1675 /* 1676 * Write the uberblock to all labels of all leaves of the specified vdev. 1677 */ 1678 static void 1679 vdev_uberblock_sync(zio_t *zio, uint64_t *good_writes, 1680 uberblock_t *ub, vdev_t *vd, int flags) 1681 { 1682 for (uint64_t c = 0; c < vd->vdev_children; c++) { 1683 vdev_uberblock_sync(zio, good_writes, 1684 ub, vd->vdev_child[c], flags); 1685 } 1686 1687 if (!vd->vdev_ops->vdev_op_leaf) 1688 return; 1689 1690 if (!vdev_writeable(vd)) 1691 return; 1692 1693 /* 1694 * There's no need to write uberblocks to a distributed spare, they 1695 * are already stored on all the leaves of the parent dRAID. For 1696 * this same reason vdev_uberblock_load_impl() skips distributed 1697 * spares when reading uberblocks. 1698 */ 1699 if (vd->vdev_ops == &vdev_draid_spare_ops) 1700 return; 1701 1702 /* If the vdev was expanded, need to copy uberblock rings. */ 1703 if (vd->vdev_state == VDEV_STATE_HEALTHY && 1704 vd->vdev_copy_uberblocks == B_TRUE) { 1705 vdev_copy_uberblocks(vd); 1706 vd->vdev_copy_uberblocks = B_FALSE; 1707 } 1708 1709 int m = spa_multihost(vd->vdev_spa) ? MMP_BLOCKS_PER_LABEL : 0; 1710 int n = ub->ub_txg % (VDEV_UBERBLOCK_COUNT(vd) - m); 1711 1712 /* Copy the uberblock_t into the ABD */ 1713 abd_t *ub_abd = abd_alloc_for_io(VDEV_UBERBLOCK_SIZE(vd), B_TRUE); 1714 abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd)); 1715 abd_copy_from_buf(ub_abd, ub, sizeof (uberblock_t)); 1716 1717 for (int l = 0; l < VDEV_LABELS; l++) 1718 vdev_label_write(zio, vd, l, ub_abd, 1719 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd), 1720 vdev_uberblock_sync_done, good_writes, 1721 flags | ZIO_FLAG_DONT_PROPAGATE); 1722 1723 abd_free(ub_abd); 1724 } 1725 1726 /* Sync the uberblocks to all vdevs in svd[] */ 1727 static int 1728 vdev_uberblock_sync_list(vdev_t **svd, int svdcount, uberblock_t *ub, int flags) 1729 { 1730 spa_t *spa = svd[0]->vdev_spa; 1731 zio_t *zio; 1732 uint64_t good_writes = 0; 1733 1734 zio = zio_root(spa, NULL, NULL, flags); 1735 1736 for (int v = 0; v < svdcount; v++) 1737 vdev_uberblock_sync(zio, &good_writes, ub, svd[v], flags); 1738 1739 (void) zio_wait(zio); 1740 1741 /* 1742 * Flush the uberblocks to disk. This ensures that the odd labels 1743 * are no longer needed (because the new uberblocks and the even 1744 * labels are safely on disk), so it is safe to overwrite them. 1745 */ 1746 zio = zio_root(spa, NULL, NULL, flags); 1747 1748 for (int v = 0; v < svdcount; v++) { 1749 if (vdev_writeable(svd[v])) { 1750 zio_flush(zio, svd[v]); 1751 } 1752 } 1753 1754 (void) zio_wait(zio); 1755 1756 return (good_writes >= 1 ? 0 : EIO); 1757 } 1758 1759 /* 1760 * On success, increment the count of good writes for our top-level vdev. 1761 */ 1762 static void 1763 vdev_label_sync_done(zio_t *zio) 1764 { 1765 uint64_t *good_writes = zio->io_private; 1766 1767 if (zio->io_error == 0) 1768 atomic_inc_64(good_writes); 1769 } 1770 1771 /* 1772 * If there weren't enough good writes, indicate failure to the parent. 1773 */ 1774 static void 1775 vdev_label_sync_top_done(zio_t *zio) 1776 { 1777 uint64_t *good_writes = zio->io_private; 1778 1779 if (*good_writes == 0) 1780 zio->io_error = SET_ERROR(EIO); 1781 1782 kmem_free(good_writes, sizeof (uint64_t)); 1783 } 1784 1785 /* 1786 * We ignore errors for log and cache devices, simply free the private data. 1787 */ 1788 static void 1789 vdev_label_sync_ignore_done(zio_t *zio) 1790 { 1791 kmem_free(zio->io_private, sizeof (uint64_t)); 1792 } 1793 1794 /* 1795 * Write all even or odd labels to all leaves of the specified vdev. 1796 */ 1797 static void 1798 vdev_label_sync(zio_t *zio, uint64_t *good_writes, 1799 vdev_t *vd, int l, uint64_t txg, int flags) 1800 { 1801 nvlist_t *label; 1802 vdev_phys_t *vp; 1803 abd_t *vp_abd; 1804 char *buf; 1805 size_t buflen; 1806 1807 for (int c = 0; c < vd->vdev_children; c++) { 1808 vdev_label_sync(zio, good_writes, 1809 vd->vdev_child[c], l, txg, flags); 1810 } 1811 1812 if (!vd->vdev_ops->vdev_op_leaf) 1813 return; 1814 1815 if (!vdev_writeable(vd)) 1816 return; 1817 1818 /* 1819 * The top-level config never needs to be written to a distributed 1820 * spare. When read vdev_dspare_label_read_config() will generate 1821 * the config for the vdev_label_read_config(). 1822 */ 1823 if (vd->vdev_ops == &vdev_draid_spare_ops) 1824 return; 1825 1826 /* 1827 * Generate a label describing the top-level config to which we belong. 1828 */ 1829 label = spa_config_generate(vd->vdev_spa, vd, txg, B_FALSE); 1830 1831 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 1832 abd_zero(vp_abd, sizeof (vdev_phys_t)); 1833 vp = abd_to_buf(vp_abd); 1834 1835 buf = vp->vp_nvlist; 1836 buflen = sizeof (vp->vp_nvlist); 1837 1838 if (!nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP)) { 1839 for (; l < VDEV_LABELS; l += 2) { 1840 vdev_label_write(zio, vd, l, vp_abd, 1841 offsetof(vdev_label_t, vl_vdev_phys), 1842 sizeof (vdev_phys_t), 1843 vdev_label_sync_done, good_writes, 1844 flags | ZIO_FLAG_DONT_PROPAGATE); 1845 } 1846 } 1847 1848 abd_free(vp_abd); 1849 nvlist_free(label); 1850 } 1851 1852 static int 1853 vdev_label_sync_list(spa_t *spa, int l, uint64_t txg, int flags) 1854 { 1855 list_t *dl = &spa->spa_config_dirty_list; 1856 vdev_t *vd; 1857 zio_t *zio; 1858 int error; 1859 1860 /* 1861 * Write the new labels to disk. 1862 */ 1863 zio = zio_root(spa, NULL, NULL, flags); 1864 1865 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) { 1866 uint64_t *good_writes; 1867 1868 ASSERT(!vd->vdev_ishole); 1869 1870 good_writes = kmem_zalloc(sizeof (uint64_t), KM_SLEEP); 1871 zio_t *vio = zio_null(zio, spa, NULL, 1872 (vd->vdev_islog || vd->vdev_aux != NULL) ? 1873 vdev_label_sync_ignore_done : vdev_label_sync_top_done, 1874 good_writes, flags); 1875 vdev_label_sync(vio, good_writes, vd, l, txg, flags); 1876 zio_nowait(vio); 1877 } 1878 1879 error = zio_wait(zio); 1880 1881 /* 1882 * Flush the new labels to disk. 1883 */ 1884 zio = zio_root(spa, NULL, NULL, flags); 1885 1886 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) 1887 zio_flush(zio, vd); 1888 1889 (void) zio_wait(zio); 1890 1891 return (error); 1892 } 1893 1894 /* 1895 * Sync the uberblock and any changes to the vdev configuration. 1896 * 1897 * The order of operations is carefully crafted to ensure that 1898 * if the system panics or loses power at any time, the state on disk 1899 * is still transactionally consistent. The in-line comments below 1900 * describe the failure semantics at each stage. 1901 * 1902 * Moreover, vdev_config_sync() is designed to be idempotent: if it fails 1903 * at any time, you can just call it again, and it will resume its work. 1904 */ 1905 int 1906 vdev_config_sync(vdev_t **svd, int svdcount, uint64_t txg) 1907 { 1908 spa_t *spa = svd[0]->vdev_spa; 1909 uberblock_t *ub = &spa->spa_uberblock; 1910 int error = 0; 1911 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; 1912 1913 ASSERT(svdcount != 0); 1914 retry: 1915 /* 1916 * Normally, we don't want to try too hard to write every label and 1917 * uberblock. If there is a flaky disk, we don't want the rest of the 1918 * sync process to block while we retry. But if we can't write a 1919 * single label out, we should retry with ZIO_FLAG_TRYHARD before 1920 * bailing out and declaring the pool faulted. 1921 */ 1922 if (error != 0) { 1923 if ((flags & ZIO_FLAG_TRYHARD) != 0) 1924 return (error); 1925 flags |= ZIO_FLAG_TRYHARD; 1926 } 1927 1928 ASSERT(ub->ub_txg <= txg); 1929 1930 /* 1931 * If this isn't a resync due to I/O errors, 1932 * and nothing changed in this transaction group, 1933 * and the vdev configuration hasn't changed, 1934 * then there's nothing to do. 1935 */ 1936 if (ub->ub_txg < txg) { 1937 boolean_t changed = uberblock_update(ub, spa->spa_root_vdev, 1938 txg, spa->spa_mmp.mmp_delay); 1939 1940 if (!changed && list_is_empty(&spa->spa_config_dirty_list)) 1941 return (0); 1942 } 1943 1944 if (txg > spa_freeze_txg(spa)) 1945 return (0); 1946 1947 ASSERT(txg <= spa->spa_final_txg); 1948 1949 /* 1950 * Flush the write cache of every disk that's been written to 1951 * in this transaction group. This ensures that all blocks 1952 * written in this txg will be committed to stable storage 1953 * before any uberblock that references them. 1954 */ 1955 zio_t *zio = zio_root(spa, NULL, NULL, flags); 1956 1957 for (vdev_t *vd = 1958 txg_list_head(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)); vd != NULL; 1959 vd = txg_list_next(&spa->spa_vdev_txg_list, vd, TXG_CLEAN(txg))) 1960 zio_flush(zio, vd); 1961 1962 (void) zio_wait(zio); 1963 1964 /* 1965 * Sync out the even labels (L0, L2) for every dirty vdev. If the 1966 * system dies in the middle of this process, that's OK: all of the 1967 * even labels that made it to disk will be newer than any uberblock, 1968 * and will therefore be considered invalid. The odd labels (L1, L3), 1969 * which have not yet been touched, will still be valid. We flush 1970 * the new labels to disk to ensure that all even-label updates 1971 * are committed to stable storage before the uberblock update. 1972 */ 1973 if ((error = vdev_label_sync_list(spa, 0, txg, flags)) != 0) { 1974 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 1975 zfs_dbgmsg("vdev_label_sync_list() returned error %d " 1976 "for pool '%s' when syncing out the even labels " 1977 "of dirty vdevs", error, spa_name(spa)); 1978 } 1979 goto retry; 1980 } 1981 1982 /* 1983 * Sync the uberblocks to all vdevs in svd[]. 1984 * If the system dies in the middle of this step, there are two cases 1985 * to consider, and the on-disk state is consistent either way: 1986 * 1987 * (1) If none of the new uberblocks made it to disk, then the 1988 * previous uberblock will be the newest, and the odd labels 1989 * (which had not yet been touched) will be valid with respect 1990 * to that uberblock. 1991 * 1992 * (2) If one or more new uberblocks made it to disk, then they 1993 * will be the newest, and the even labels (which had all 1994 * been successfully committed) will be valid with respect 1995 * to the new uberblocks. 1996 */ 1997 if ((error = vdev_uberblock_sync_list(svd, svdcount, ub, flags)) != 0) { 1998 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 1999 zfs_dbgmsg("vdev_uberblock_sync_list() returned error " 2000 "%d for pool '%s'", error, spa_name(spa)); 2001 } 2002 goto retry; 2003 } 2004 2005 if (spa_multihost(spa)) 2006 mmp_update_uberblock(spa, ub); 2007 2008 /* 2009 * Sync out odd labels for every dirty vdev. If the system dies 2010 * in the middle of this process, the even labels and the new 2011 * uberblocks will suffice to open the pool. The next time 2012 * the pool is opened, the first thing we'll do -- before any 2013 * user data is modified -- is mark every vdev dirty so that 2014 * all labels will be brought up to date. We flush the new labels 2015 * to disk to ensure that all odd-label updates are committed to 2016 * stable storage before the next transaction group begins. 2017 */ 2018 if ((error = vdev_label_sync_list(spa, 1, txg, flags)) != 0) { 2019 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 2020 zfs_dbgmsg("vdev_label_sync_list() returned error %d " 2021 "for pool '%s' when syncing out the odd labels of " 2022 "dirty vdevs", error, spa_name(spa)); 2023 } 2024 goto retry; 2025 } 2026 2027 return (0); 2028 } 2029