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