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, 2018 by Delphix. All rights reserved. 25 * Copyright (c) 2017, Intel Corporation. 26 * Copyright 2020 Joyent, Inc. 27 */ 28 29 /* 30 * Virtual Device Labels 31 * --------------------- 32 * 33 * The vdev label serves several distinct purposes: 34 * 35 * 1. Uniquely identify this device as part of a ZFS pool and confirm its 36 * identity within the pool. 37 * 38 * 2. Verify that all the devices given in a configuration are present 39 * within the pool. 40 * 41 * 3. Determine the uberblock for the pool. 42 * 43 * 4. In case of an import operation, determine the configuration of the 44 * toplevel vdev of which it is a part. 45 * 46 * 5. If an import operation cannot find all the devices in the pool, 47 * provide enough information to the administrator to determine which 48 * devices are missing. 49 * 50 * It is important to note that while the kernel is responsible for writing the 51 * label, it only consumes the information in the first three cases. The 52 * latter information is only consumed in userland when determining the 53 * configuration to import a pool. 54 * 55 * 56 * Label Organization 57 * ------------------ 58 * 59 * Before describing the contents of the label, it's important to understand how 60 * the labels are written and updated with respect to the uberblock. 61 * 62 * When the pool configuration is altered, either because it was newly created 63 * or a device was added, we want to update all the labels such that we can deal 64 * with fatal failure at any point. To this end, each disk has two labels which 65 * are updated before and after the uberblock is synced. Assuming we have 66 * labels and an uberblock with the following transaction groups: 67 * 68 * L1 UB L2 69 * +------+ +------+ +------+ 70 * | | | | | | 71 * | t10 | | t10 | | t10 | 72 * | | | | | | 73 * +------+ +------+ +------+ 74 * 75 * In this stable state, the labels and the uberblock were all updated within 76 * the same transaction group (10). Each label is mirrored and checksummed, so 77 * that we can detect when we fail partway through writing the label. 78 * 79 * In order to identify which labels are valid, the labels are written in the 80 * following manner: 81 * 82 * 1. For each vdev, update 'L1' to the new label 83 * 2. Update the uberblock 84 * 3. For each vdev, update 'L2' to the new label 85 * 86 * Given arbitrary failure, we can determine the correct label to use based on 87 * the transaction group. If we fail after updating L1 but before updating the 88 * UB, we will notice that L1's transaction group is greater than the uberblock, 89 * so L2 must be valid. If we fail after writing the uberblock but before 90 * writing L2, we will notice that L2's transaction group is less than L1, and 91 * therefore L1 is valid. 92 * 93 * Another added complexity is that not every label is updated when the config 94 * is synced. If we add a single device, we do not want to have to re-write 95 * every label for every device in the pool. This means that both L1 and L2 may 96 * be older than the pool uberblock, because the necessary information is stored 97 * on another vdev. 98 * 99 * 100 * On-disk Format 101 * -------------- 102 * 103 * The vdev label consists of two distinct parts, and is wrapped within the 104 * vdev_label_t structure. The label includes 8k of padding to permit legacy 105 * VTOC disk labels, but is otherwise ignored. 106 * 107 * The first half of the label is a packed nvlist which contains pool wide 108 * properties, per-vdev properties, and configuration information. It is 109 * described in more detail below. 110 * 111 * The latter half of the label consists of a redundant array of uberblocks. 112 * These uberblocks are updated whenever a transaction group is committed, 113 * or when the configuration is updated. When a pool is loaded, we scan each 114 * vdev for the 'best' uberblock. 115 * 116 * 117 * Configuration Information 118 * ------------------------- 119 * 120 * The nvlist describing the pool and vdev contains the following elements: 121 * 122 * version ZFS on-disk version 123 * name Pool name 124 * state Pool state 125 * txg Transaction group in which this label was written 126 * pool_guid Unique identifier for this pool 127 * vdev_tree An nvlist describing vdev tree. 128 * features_for_read 129 * An nvlist of the features necessary for reading the MOS. 130 * 131 * Each leaf device label also contains the following: 132 * 133 * top_guid Unique ID for top-level vdev in which this is contained 134 * guid Unique ID for the leaf vdev 135 * 136 * The 'vs' configuration follows the format described in 'spa_config.c'. 137 */ 138 139 #include <sys/zfs_context.h> 140 #include <sys/spa.h> 141 #include <sys/spa_impl.h> 142 #include <sys/dmu.h> 143 #include <sys/zap.h> 144 #include <sys/vdev.h> 145 #include <sys/vdev_impl.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> 153 154 /* 155 * Basic routines to read and write from a vdev label. 156 * Used throughout the rest of this file. 157 */ 158 uint64_t 159 vdev_label_offset(uint64_t psize, int l, uint64_t offset) 160 { 161 ASSERT(offset < sizeof (vdev_label_t)); 162 ASSERT(P2PHASE_TYPED(psize, sizeof (vdev_label_t), uint64_t) == 0); 163 164 return (offset + l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ? 165 0 : psize - VDEV_LABELS * sizeof (vdev_label_t))); 166 } 167 168 /* 169 * Returns back the vdev label associated with the passed in offset. 170 */ 171 int 172 vdev_label_number(uint64_t psize, uint64_t offset) 173 { 174 int l; 175 176 if (offset >= psize - VDEV_LABEL_END_SIZE) { 177 offset -= psize - VDEV_LABEL_END_SIZE; 178 offset += (VDEV_LABELS / 2) * sizeof (vdev_label_t); 179 } 180 l = offset / sizeof (vdev_label_t); 181 return (l < VDEV_LABELS ? l : -1); 182 } 183 184 static void 185 vdev_label_read(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset, 186 uint64_t size, zio_done_func_t *done, void *private, int flags) 187 { 188 ASSERT( 189 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE || 190 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE); 191 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER); 192 193 zio_nowait(zio_read_phys(zio, vd, 194 vdev_label_offset(vd->vdev_psize, l, offset), 195 size, buf, ZIO_CHECKSUM_LABEL, done, private, 196 ZIO_PRIORITY_SYNC_READ, flags, B_TRUE)); 197 } 198 199 void 200 vdev_label_write(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset, 201 uint64_t size, zio_done_func_t *done, void *private, int flags) 202 { 203 ASSERT( 204 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE || 205 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE); 206 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER); 207 208 zio_nowait(zio_write_phys(zio, vd, 209 vdev_label_offset(vd->vdev_psize, l, offset), 210 size, buf, ZIO_CHECKSUM_LABEL, done, private, 211 ZIO_PRIORITY_SYNC_WRITE, flags, B_TRUE)); 212 } 213 214 /* 215 * Generate the nvlist representing this vdev's stats 216 */ 217 void 218 vdev_config_generate_stats(vdev_t *vd, nvlist_t *nv) 219 { 220 nvlist_t *nvx; 221 vdev_stat_t *vs; 222 vdev_stat_ex_t *vsx; 223 224 vs = kmem_alloc(sizeof (*vs), KM_SLEEP); 225 vsx = kmem_alloc(sizeof (*vsx), KM_SLEEP); 226 227 vdev_get_stats_ex(vd, vs, vsx); 228 fnvlist_add_uint64_array(nv, ZPOOL_CONFIG_VDEV_STATS, 229 (uint64_t *)vs, sizeof (*vs) / sizeof (uint64_t)); 230 231 /* 232 * Add extended stats into a special extended stats nvlist. This keeps 233 * all the extended stats nicely grouped together. The extended stats 234 * nvlist is then added to the main nvlist. 235 */ 236 nvx = fnvlist_alloc(); 237 238 /* ZIOs in flight to disk */ 239 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_ACTIVE_QUEUE, 240 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_READ]); 241 242 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_ACTIVE_QUEUE, 243 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_WRITE]); 244 245 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_ACTIVE_QUEUE, 246 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_READ]); 247 248 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_ACTIVE_QUEUE, 249 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_WRITE]); 250 251 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_ACTIVE_QUEUE, 252 vsx->vsx_active_queue[ZIO_PRIORITY_SCRUB]); 253 254 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_ACTIVE_QUEUE, 255 vsx->vsx_active_queue[ZIO_PRIORITY_TRIM]); 256 257 /* ZIOs pending */ 258 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_PEND_QUEUE, 259 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_READ]); 260 261 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_PEND_QUEUE, 262 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_WRITE]); 263 264 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_PEND_QUEUE, 265 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_READ]); 266 267 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_PEND_QUEUE, 268 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_WRITE]); 269 270 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_PEND_QUEUE, 271 vsx->vsx_pend_queue[ZIO_PRIORITY_SCRUB]); 272 273 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_PEND_QUEUE, 274 vsx->vsx_pend_queue[ZIO_PRIORITY_TRIM]); 275 276 /* Histograms */ 277 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_R_LAT_HISTO, 278 vsx->vsx_total_histo[ZIO_TYPE_READ], 279 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_READ])); 280 281 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_W_LAT_HISTO, 282 vsx->vsx_total_histo[ZIO_TYPE_WRITE], 283 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_WRITE])); 284 285 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_R_LAT_HISTO, 286 vsx->vsx_disk_histo[ZIO_TYPE_READ], 287 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_READ])); 288 289 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_W_LAT_HISTO, 290 vsx->vsx_disk_histo[ZIO_TYPE_WRITE], 291 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_WRITE])); 292 293 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_LAT_HISTO, 294 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ], 295 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ])); 296 297 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_LAT_HISTO, 298 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE], 299 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE])); 300 301 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_LAT_HISTO, 302 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ], 303 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ])); 304 305 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_LAT_HISTO, 306 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE], 307 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE])); 308 309 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SCRUB_LAT_HISTO, 310 vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB], 311 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB])); 312 313 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TRIM_LAT_HISTO, 314 vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM], 315 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM])); 316 317 /* Request sizes */ 318 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_R_HISTO, 319 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ], 320 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ])); 321 322 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_W_HISTO, 323 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE], 324 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE])); 325 326 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_R_HISTO, 327 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ], 328 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ])); 329 330 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_W_HISTO, 331 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE], 332 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE])); 333 334 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_SCRUB_HISTO, 335 vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB], 336 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB])); 337 338 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_TRIM_HISTO, 339 vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM], 340 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM])); 341 342 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_R_HISTO, 343 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ], 344 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ])); 345 346 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_W_HISTO, 347 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE], 348 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE])); 349 350 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_R_HISTO, 351 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ], 352 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ])); 353 354 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_W_HISTO, 355 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE], 356 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE])); 357 358 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_SCRUB_HISTO, 359 vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB], 360 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB])); 361 362 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_TRIM_HISTO, 363 vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM], 364 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM])); 365 366 /* IO delays */ 367 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SLOW_IOS, vs->vs_slow_ios); 368 369 /* Add extended stats nvlist to main nvlist */ 370 fnvlist_add_nvlist(nv, ZPOOL_CONFIG_VDEV_STATS_EX, nvx); 371 372 nvlist_free(nvx); 373 kmem_free(vs, sizeof (*vs)); 374 kmem_free(vsx, sizeof (*vsx)); 375 } 376 377 static void 378 root_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl) 379 { 380 spa_t *spa = vd->vdev_spa; 381 382 if (vd != spa->spa_root_vdev) 383 return; 384 385 /* provide either current or previous scan information */ 386 pool_scan_stat_t ps; 387 if (spa_scan_get_stats(spa, &ps) == 0) { 388 fnvlist_add_uint64_array(nvl, 389 ZPOOL_CONFIG_SCAN_STATS, (uint64_t *)&ps, 390 sizeof (pool_scan_stat_t) / sizeof (uint64_t)); 391 } 392 393 pool_removal_stat_t prs; 394 if (spa_removal_get_stats(spa, &prs) == 0) { 395 fnvlist_add_uint64_array(nvl, 396 ZPOOL_CONFIG_REMOVAL_STATS, (uint64_t *)&prs, 397 sizeof (prs) / sizeof (uint64_t)); 398 } 399 400 pool_checkpoint_stat_t pcs; 401 if (spa_checkpoint_get_stats(spa, &pcs) == 0) { 402 fnvlist_add_uint64_array(nvl, 403 ZPOOL_CONFIG_CHECKPOINT_STATS, (uint64_t *)&pcs, 404 sizeof (pcs) / sizeof (uint64_t)); 405 } 406 } 407 408 /* 409 * Generate the nvlist representing this vdev's config. 410 */ 411 nvlist_t * 412 vdev_config_generate(spa_t *spa, vdev_t *vd, boolean_t getstats, 413 vdev_config_flag_t flags) 414 { 415 nvlist_t *nv = NULL; 416 vdev_indirect_config_t *vic = &vd->vdev_indirect_config; 417 418 nv = fnvlist_alloc(); 419 420 fnvlist_add_string(nv, ZPOOL_CONFIG_TYPE, vd->vdev_ops->vdev_op_type); 421 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE))) 422 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ID, vd->vdev_id); 423 fnvlist_add_uint64(nv, ZPOOL_CONFIG_GUID, vd->vdev_guid); 424 425 if (vd->vdev_path != NULL) 426 fnvlist_add_string(nv, ZPOOL_CONFIG_PATH, vd->vdev_path); 427 428 if (vd->vdev_devid != NULL) 429 fnvlist_add_string(nv, ZPOOL_CONFIG_DEVID, vd->vdev_devid); 430 431 if (vd->vdev_physpath != NULL) 432 fnvlist_add_string(nv, ZPOOL_CONFIG_PHYS_PATH, 433 vd->vdev_physpath); 434 435 if (vd->vdev_fru != NULL) 436 fnvlist_add_string(nv, ZPOOL_CONFIG_FRU, vd->vdev_fru); 437 438 if (vd->vdev_nparity != 0) { 439 ASSERT(strcmp(vd->vdev_ops->vdev_op_type, 440 VDEV_TYPE_RAIDZ) == 0); 441 442 /* 443 * Make sure someone hasn't managed to sneak a fancy new vdev 444 * into a crufty old storage pool. 445 */ 446 ASSERT(vd->vdev_nparity == 1 || 447 (vd->vdev_nparity <= 2 && 448 spa_version(spa) >= SPA_VERSION_RAIDZ2) || 449 (vd->vdev_nparity <= 3 && 450 spa_version(spa) >= SPA_VERSION_RAIDZ3)); 451 452 /* 453 * Note that we'll add the nparity tag even on storage pools 454 * that only support a single parity device -- older software 455 * will just ignore it. 456 */ 457 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NPARITY, vd->vdev_nparity); 458 } 459 460 if (vd->vdev_wholedisk != -1ULL) 461 fnvlist_add_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK, 462 vd->vdev_wholedisk); 463 464 if (vd->vdev_not_present && !(flags & VDEV_CONFIG_MISSING)) 465 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NOT_PRESENT, 1); 466 467 if (vd->vdev_isspare) 468 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_SPARE, 1); 469 470 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE)) && 471 vd == vd->vdev_top) { 472 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_ARRAY, 473 vd->vdev_ms_array); 474 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_SHIFT, 475 vd->vdev_ms_shift); 476 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASHIFT, vd->vdev_ashift); 477 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASIZE, 478 vd->vdev_asize); 479 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_LOG, vd->vdev_islog); 480 if (vd->vdev_removing) { 481 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVING, 482 vd->vdev_removing); 483 } 484 485 /* zpool command expects alloc class data */ 486 if (getstats && vd->vdev_alloc_bias != VDEV_BIAS_NONE) { 487 const char *bias = NULL; 488 489 switch (vd->vdev_alloc_bias) { 490 case VDEV_BIAS_LOG: 491 bias = VDEV_ALLOC_BIAS_LOG; 492 break; 493 case VDEV_BIAS_SPECIAL: 494 bias = VDEV_ALLOC_BIAS_SPECIAL; 495 break; 496 case VDEV_BIAS_DEDUP: 497 bias = VDEV_ALLOC_BIAS_DEDUP; 498 break; 499 default: 500 ASSERT3U(vd->vdev_alloc_bias, ==, 501 VDEV_BIAS_NONE); 502 } 503 fnvlist_add_string(nv, ZPOOL_CONFIG_ALLOCATION_BIAS, 504 bias); 505 } 506 } 507 508 if (vd->vdev_dtl_sm != NULL) { 509 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DTL, 510 space_map_object(vd->vdev_dtl_sm)); 511 } 512 513 if (vic->vic_mapping_object != 0) { 514 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_OBJECT, 515 vic->vic_mapping_object); 516 } 517 518 if (vic->vic_births_object != 0) { 519 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_BIRTHS, 520 vic->vic_births_object); 521 } 522 523 if (vic->vic_prev_indirect_vdev != UINT64_MAX) { 524 fnvlist_add_uint64(nv, ZPOOL_CONFIG_PREV_INDIRECT_VDEV, 525 vic->vic_prev_indirect_vdev); 526 } 527 528 if (vd->vdev_crtxg) 529 fnvlist_add_uint64(nv, ZPOOL_CONFIG_CREATE_TXG, vd->vdev_crtxg); 530 531 if (flags & VDEV_CONFIG_MOS) { 532 if (vd->vdev_leaf_zap != 0) { 533 ASSERT(vd->vdev_ops->vdev_op_leaf); 534 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_LEAF_ZAP, 535 vd->vdev_leaf_zap); 536 } 537 538 if (vd->vdev_top_zap != 0) { 539 ASSERT(vd == vd->vdev_top); 540 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_TOP_ZAP, 541 vd->vdev_top_zap); 542 } 543 544 if (vd->vdev_resilver_deferred) { 545 ASSERT(vd->vdev_ops->vdev_op_leaf); 546 ASSERT(spa->spa_resilver_deferred); 547 fnvlist_add_boolean(nv, ZPOOL_CONFIG_RESILVER_DEFER); 548 } 549 } 550 551 if (getstats) { 552 vdev_config_generate_stats(vd, nv); 553 554 root_vdev_actions_getprogress(vd, nv); 555 556 /* 557 * Note: this can be called from open context 558 * (spa_get_stats()), so we need the rwlock to prevent 559 * the mapping from being changed by condensing. 560 */ 561 rw_enter(&vd->vdev_indirect_rwlock, RW_READER); 562 if (vd->vdev_indirect_mapping != NULL) { 563 ASSERT(vd->vdev_indirect_births != NULL); 564 vdev_indirect_mapping_t *vim = 565 vd->vdev_indirect_mapping; 566 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE, 567 vdev_indirect_mapping_size(vim)); 568 } 569 rw_exit(&vd->vdev_indirect_rwlock); 570 if (vd->vdev_mg != NULL && 571 vd->vdev_mg->mg_fragmentation != ZFS_FRAG_INVALID) { 572 /* 573 * Compute approximately how much memory would be used 574 * for the indirect mapping if this device were to 575 * be removed. 576 * 577 * Note: If the frag metric is invalid, then not 578 * enough metaslabs have been converted to have 579 * histograms. 580 */ 581 uint64_t seg_count = 0; 582 uint64_t to_alloc = vd->vdev_stat.vs_alloc; 583 584 /* 585 * There are the same number of allocated segments 586 * as free segments, so we will have at least one 587 * entry per free segment. However, small free 588 * segments (smaller than vdev_removal_max_span) 589 * will be combined with adjacent allocated segments 590 * as a single mapping. 591 */ 592 for (int i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) { 593 if (1ULL << (i + 1) < vdev_removal_max_span) { 594 to_alloc += 595 vd->vdev_mg->mg_histogram[i] << 596 i + 1; 597 } else { 598 seg_count += 599 vd->vdev_mg->mg_histogram[i]; 600 } 601 } 602 603 /* 604 * The maximum length of a mapping is 605 * zfs_remove_max_segment, so we need at least one entry 606 * per zfs_remove_max_segment of allocated data. 607 */ 608 seg_count += to_alloc / zfs_remove_max_segment; 609 610 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE, 611 seg_count * 612 sizeof (vdev_indirect_mapping_entry_phys_t)); 613 } 614 } 615 616 if (!vd->vdev_ops->vdev_op_leaf) { 617 nvlist_t **child; 618 int c, idx; 619 620 ASSERT(!vd->vdev_ishole); 621 622 child = kmem_alloc(vd->vdev_children * sizeof (nvlist_t *), 623 KM_SLEEP); 624 625 for (c = 0, idx = 0; c < vd->vdev_children; c++) { 626 vdev_t *cvd = vd->vdev_child[c]; 627 628 /* 629 * If we're generating an nvlist of removing 630 * vdevs then skip over any device which is 631 * not being removed. 632 */ 633 if ((flags & VDEV_CONFIG_REMOVING) && 634 !cvd->vdev_removing) 635 continue; 636 637 child[idx++] = vdev_config_generate(spa, cvd, 638 getstats, flags); 639 } 640 641 if (idx) { 642 fnvlist_add_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN, 643 child, idx); 644 } 645 646 for (c = 0; c < idx; c++) 647 nvlist_free(child[c]); 648 649 kmem_free(child, vd->vdev_children * sizeof (nvlist_t *)); 650 651 } else { 652 const char *aux = NULL; 653 654 if (vd->vdev_offline && !vd->vdev_tmpoffline) 655 fnvlist_add_uint64(nv, ZPOOL_CONFIG_OFFLINE, B_TRUE); 656 if (vd->vdev_resilver_txg != 0) 657 fnvlist_add_uint64(nv, ZPOOL_CONFIG_RESILVER_TXG, 658 vd->vdev_resilver_txg); 659 if (vd->vdev_faulted) 660 fnvlist_add_uint64(nv, ZPOOL_CONFIG_FAULTED, B_TRUE); 661 if (vd->vdev_degraded) 662 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DEGRADED, B_TRUE); 663 if (vd->vdev_removed) 664 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVED, B_TRUE); 665 if (vd->vdev_unspare) 666 fnvlist_add_uint64(nv, ZPOOL_CONFIG_UNSPARE, B_TRUE); 667 if (vd->vdev_ishole) 668 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_HOLE, B_TRUE); 669 670 switch (vd->vdev_stat.vs_aux) { 671 case VDEV_AUX_ERR_EXCEEDED: 672 aux = "err_exceeded"; 673 break; 674 675 case VDEV_AUX_EXTERNAL: 676 aux = "external"; 677 break; 678 } 679 680 if (aux != NULL) 681 fnvlist_add_string(nv, ZPOOL_CONFIG_AUX_STATE, aux); 682 683 if (vd->vdev_splitting && vd->vdev_orig_guid != 0LL) { 684 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ORIG_GUID, 685 vd->vdev_orig_guid); 686 } 687 } 688 689 return (nv); 690 } 691 692 /* 693 * Generate a view of the top-level vdevs. If we currently have holes 694 * in the namespace, then generate an array which contains a list of holey 695 * vdevs. Additionally, add the number of top-level children that currently 696 * exist. 697 */ 698 void 699 vdev_top_config_generate(spa_t *spa, nvlist_t *config) 700 { 701 vdev_t *rvd = spa->spa_root_vdev; 702 uint64_t *array; 703 uint_t c, idx; 704 705 array = kmem_alloc(rvd->vdev_children * sizeof (uint64_t), KM_SLEEP); 706 707 for (c = 0, idx = 0; c < rvd->vdev_children; c++) { 708 vdev_t *tvd = rvd->vdev_child[c]; 709 710 if (tvd->vdev_ishole) { 711 array[idx++] = c; 712 } 713 } 714 715 if (idx) { 716 VERIFY(nvlist_add_uint64_array(config, ZPOOL_CONFIG_HOLE_ARRAY, 717 array, idx) == 0); 718 } 719 720 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN, 721 rvd->vdev_children) == 0); 722 723 kmem_free(array, rvd->vdev_children * sizeof (uint64_t)); 724 } 725 726 /* 727 * Returns the configuration from the label of the given vdev. For vdevs 728 * which don't have a txg value stored on their label (i.e. spares/cache) 729 * or have not been completely initialized (txg = 0) just return 730 * the configuration from the first valid label we find. Otherwise, 731 * find the most up-to-date label that does not exceed the specified 732 * 'txg' value. 733 */ 734 nvlist_t * 735 vdev_label_read_config(vdev_t *vd, uint64_t txg) 736 { 737 spa_t *spa = vd->vdev_spa; 738 nvlist_t *config = NULL; 739 vdev_phys_t *vp; 740 abd_t *vp_abd; 741 zio_t *zio; 742 uint64_t best_txg = 0; 743 uint64_t label_txg = 0; 744 int error = 0; 745 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 746 ZIO_FLAG_SPECULATIVE; 747 748 ASSERT(spa_config_held(spa, SCL_STATE_ALL, RW_WRITER) == SCL_STATE_ALL); 749 750 if (!vdev_readable(vd)) 751 return (NULL); 752 753 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 754 vp = abd_to_buf(vp_abd); 755 756 retry: 757 for (int l = 0; l < VDEV_LABELS; l++) { 758 nvlist_t *label = NULL; 759 760 zio = zio_root(spa, NULL, NULL, flags); 761 762 vdev_label_read(zio, vd, l, vp_abd, 763 offsetof(vdev_label_t, vl_vdev_phys), 764 sizeof (vdev_phys_t), NULL, NULL, flags); 765 766 if (zio_wait(zio) == 0 && 767 nvlist_unpack(vp->vp_nvlist, sizeof (vp->vp_nvlist), 768 &label, 0) == 0) { 769 /* 770 * Auxiliary vdevs won't have txg values in their 771 * labels and newly added vdevs may not have been 772 * completely initialized so just return the 773 * configuration from the first valid label we 774 * encounter. 775 */ 776 error = nvlist_lookup_uint64(label, 777 ZPOOL_CONFIG_POOL_TXG, &label_txg); 778 if ((error || label_txg == 0) && !config) { 779 config = label; 780 break; 781 } else if (label_txg <= txg && label_txg > best_txg) { 782 best_txg = label_txg; 783 nvlist_free(config); 784 config = fnvlist_dup(label); 785 } 786 } 787 788 if (label != NULL) { 789 nvlist_free(label); 790 label = NULL; 791 } 792 } 793 794 if (config == NULL && !(flags & ZIO_FLAG_TRYHARD)) { 795 flags |= ZIO_FLAG_TRYHARD; 796 goto retry; 797 } 798 799 /* 800 * We found a valid label but it didn't pass txg restrictions. 801 */ 802 if (config == NULL && label_txg != 0) { 803 vdev_dbgmsg(vd, "label discarded as txg is too large " 804 "(%llu > %llu)", (u_longlong_t)label_txg, 805 (u_longlong_t)txg); 806 } 807 808 abd_free(vp_abd); 809 810 return (config); 811 } 812 813 /* 814 * Determine if a device is in use. The 'spare_guid' parameter will be filled 815 * in with the device guid if this spare is active elsewhere on the system. 816 */ 817 static boolean_t 818 vdev_inuse(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason, 819 uint64_t *spare_guid, uint64_t *l2cache_guid) 820 { 821 spa_t *spa = vd->vdev_spa; 822 uint64_t state, pool_guid, device_guid, txg, spare_pool; 823 uint64_t vdtxg = 0; 824 nvlist_t *label; 825 826 if (spare_guid) 827 *spare_guid = 0ULL; 828 if (l2cache_guid) 829 *l2cache_guid = 0ULL; 830 831 /* 832 * Read the label, if any, and perform some basic sanity checks. 833 */ 834 if ((label = vdev_label_read_config(vd, -1ULL)) == NULL) 835 return (B_FALSE); 836 837 (void) nvlist_lookup_uint64(label, ZPOOL_CONFIG_CREATE_TXG, 838 &vdtxg); 839 840 if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_STATE, 841 &state) != 0 || 842 nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID, 843 &device_guid) != 0) { 844 nvlist_free(label); 845 return (B_FALSE); 846 } 847 848 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 849 (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID, 850 &pool_guid) != 0 || 851 nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG, 852 &txg) != 0)) { 853 nvlist_free(label); 854 return (B_FALSE); 855 } 856 857 nvlist_free(label); 858 859 /* 860 * Check to see if this device indeed belongs to the pool it claims to 861 * be a part of. The only way this is allowed is if the device is a hot 862 * spare (which we check for later on). 863 */ 864 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 865 !spa_guid_exists(pool_guid, device_guid) && 866 !spa_spare_exists(device_guid, NULL, NULL) && 867 !spa_l2cache_exists(device_guid, NULL)) 868 return (B_FALSE); 869 870 /* 871 * If the transaction group is zero, then this an initialized (but 872 * unused) label. This is only an error if the create transaction 873 * on-disk is the same as the one we're using now, in which case the 874 * user has attempted to add the same vdev multiple times in the same 875 * transaction. 876 */ 877 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 878 txg == 0 && vdtxg == crtxg) 879 return (B_TRUE); 880 881 /* 882 * Check to see if this is a spare device. We do an explicit check for 883 * spa_has_spare() here because it may be on our pending list of spares 884 * to add. We also check if it is an l2cache device. 885 */ 886 if (spa_spare_exists(device_guid, &spare_pool, NULL) || 887 spa_has_spare(spa, device_guid)) { 888 if (spare_guid) 889 *spare_guid = device_guid; 890 891 switch (reason) { 892 case VDEV_LABEL_CREATE: 893 case VDEV_LABEL_L2CACHE: 894 return (B_TRUE); 895 896 case VDEV_LABEL_REPLACE: 897 return (!spa_has_spare(spa, device_guid) || 898 spare_pool != 0ULL); 899 900 case VDEV_LABEL_SPARE: 901 return (spa_has_spare(spa, device_guid)); 902 } 903 } 904 905 /* 906 * Check to see if this is an l2cache device. 907 */ 908 if (spa_l2cache_exists(device_guid, NULL)) 909 return (B_TRUE); 910 911 /* 912 * We can't rely on a pool's state if it's been imported 913 * read-only. Instead we look to see if the pools is marked 914 * read-only in the namespace and set the state to active. 915 */ 916 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 917 (spa = spa_by_guid(pool_guid, device_guid)) != NULL && 918 spa_mode(spa) == FREAD) 919 state = POOL_STATE_ACTIVE; 920 921 /* 922 * If the device is marked ACTIVE, then this device is in use by another 923 * pool on the system. 924 */ 925 return (state == POOL_STATE_ACTIVE); 926 } 927 928 /* 929 * Initialize a vdev label. We check to make sure each leaf device is not in 930 * use, and writable. We put down an initial label which we will later 931 * overwrite with a complete label. Note that it's important to do this 932 * sequentially, not in parallel, so that we catch cases of multiple use of the 933 * same leaf vdev in the vdev we're creating -- e.g. mirroring a disk with 934 * itself. 935 */ 936 int 937 vdev_label_init(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason) 938 { 939 spa_t *spa = vd->vdev_spa; 940 nvlist_t *label; 941 vdev_phys_t *vp; 942 abd_t *vp_abd; 943 abd_t *pad2; 944 uberblock_t *ub; 945 abd_t *ub_abd; 946 zio_t *zio; 947 char *buf; 948 size_t buflen; 949 int error; 950 uint64_t spare_guid, l2cache_guid; 951 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; 952 953 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); 954 955 for (int c = 0; c < vd->vdev_children; c++) 956 if ((error = vdev_label_init(vd->vdev_child[c], 957 crtxg, reason)) != 0) 958 return (error); 959 960 /* Track the creation time for this vdev */ 961 vd->vdev_crtxg = crtxg; 962 963 if (!vd->vdev_ops->vdev_op_leaf || !spa_writeable(spa)) 964 return (0); 965 966 /* 967 * Dead vdevs cannot be initialized. 968 */ 969 if (vdev_is_dead(vd)) 970 return (SET_ERROR(EIO)); 971 972 /* 973 * Determine if the vdev is in use. 974 */ 975 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPLIT && 976 vdev_inuse(vd, crtxg, reason, &spare_guid, &l2cache_guid)) 977 return (SET_ERROR(EBUSY)); 978 979 /* 980 * If this is a request to add or replace a spare or l2cache device 981 * that is in use elsewhere on the system, then we must update the 982 * guid (which was initialized to a random value) to reflect the 983 * actual GUID (which is shared between multiple pools). 984 */ 985 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_L2CACHE && 986 spare_guid != 0ULL) { 987 uint64_t guid_delta = spare_guid - vd->vdev_guid; 988 989 vd->vdev_guid += guid_delta; 990 991 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent) 992 pvd->vdev_guid_sum += guid_delta; 993 994 /* 995 * If this is a replacement, then we want to fallthrough to the 996 * rest of the code. If we're adding a spare, then it's already 997 * labeled appropriately and we can just return. 998 */ 999 if (reason == VDEV_LABEL_SPARE) 1000 return (0); 1001 ASSERT(reason == VDEV_LABEL_REPLACE || 1002 reason == VDEV_LABEL_SPLIT); 1003 } 1004 1005 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPARE && 1006 l2cache_guid != 0ULL) { 1007 uint64_t guid_delta = l2cache_guid - vd->vdev_guid; 1008 1009 vd->vdev_guid += guid_delta; 1010 1011 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent) 1012 pvd->vdev_guid_sum += guid_delta; 1013 1014 /* 1015 * If this is a replacement, then we want to fallthrough to the 1016 * rest of the code. If we're adding an l2cache, then it's 1017 * already labeled appropriately and we can just return. 1018 */ 1019 if (reason == VDEV_LABEL_L2CACHE) 1020 return (0); 1021 ASSERT(reason == VDEV_LABEL_REPLACE); 1022 } 1023 1024 /* 1025 * Initialize its label. 1026 */ 1027 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 1028 abd_zero(vp_abd, sizeof (vdev_phys_t)); 1029 vp = abd_to_buf(vp_abd); 1030 1031 /* 1032 * Generate a label describing the pool and our top-level vdev. 1033 * We mark it as being from txg 0 to indicate that it's not 1034 * really part of an active pool just yet. The labels will 1035 * be written again with a meaningful txg by spa_sync(). 1036 */ 1037 if (reason == VDEV_LABEL_SPARE || 1038 (reason == VDEV_LABEL_REMOVE && vd->vdev_isspare)) { 1039 /* 1040 * For inactive hot spares, we generate a special label that 1041 * identifies as a mutually shared hot spare. We write the 1042 * label if we are adding a hot spare, or if we are removing an 1043 * active hot spare (in which case we want to revert the 1044 * labels). 1045 */ 1046 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1047 1048 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION, 1049 spa_version(spa)) == 0); 1050 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE, 1051 POOL_STATE_SPARE) == 0); 1052 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID, 1053 vd->vdev_guid) == 0); 1054 } else if (reason == VDEV_LABEL_L2CACHE || 1055 (reason == VDEV_LABEL_REMOVE && vd->vdev_isl2cache)) { 1056 /* 1057 * For level 2 ARC devices, add a special label. 1058 */ 1059 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1060 1061 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION, 1062 spa_version(spa)) == 0); 1063 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE, 1064 POOL_STATE_L2CACHE) == 0); 1065 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID, 1066 vd->vdev_guid) == 0); 1067 } else { 1068 uint64_t txg = 0ULL; 1069 1070 if (reason == VDEV_LABEL_SPLIT) 1071 txg = spa->spa_uberblock.ub_txg; 1072 label = spa_config_generate(spa, vd, txg, B_FALSE); 1073 1074 /* 1075 * Add our creation time. This allows us to detect multiple 1076 * vdev uses as described above, and automatically expires if we 1077 * fail. 1078 */ 1079 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_CREATE_TXG, 1080 crtxg) == 0); 1081 } 1082 1083 buf = vp->vp_nvlist; 1084 buflen = sizeof (vp->vp_nvlist); 1085 1086 error = nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP); 1087 if (error != 0) { 1088 nvlist_free(label); 1089 abd_free(vp_abd); 1090 /* EFAULT means nvlist_pack ran out of room */ 1091 return (error == EFAULT ? ENAMETOOLONG : EINVAL); 1092 } 1093 1094 /* 1095 * Initialize uberblock template. 1096 */ 1097 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_RING, B_TRUE); 1098 abd_zero(ub_abd, VDEV_UBERBLOCK_RING); 1099 abd_copy_from_buf(ub_abd, &spa->spa_uberblock, sizeof (uberblock_t)); 1100 ub = abd_to_buf(ub_abd); 1101 ub->ub_txg = 0; 1102 1103 /* Initialize the 2nd padding area. */ 1104 pad2 = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE); 1105 abd_zero(pad2, VDEV_PAD_SIZE); 1106 1107 /* 1108 * Write everything in parallel. 1109 */ 1110 retry: 1111 zio = zio_root(spa, NULL, NULL, flags); 1112 1113 for (int l = 0; l < VDEV_LABELS; l++) { 1114 1115 vdev_label_write(zio, vd, l, vp_abd, 1116 offsetof(vdev_label_t, vl_vdev_phys), 1117 sizeof (vdev_phys_t), NULL, NULL, flags); 1118 1119 /* 1120 * Skip the 1st padding area. 1121 * Zero out the 2nd padding area where it might have 1122 * left over data from previous filesystem format. 1123 */ 1124 vdev_label_write(zio, vd, l, pad2, 1125 offsetof(vdev_label_t, vl_pad2), 1126 VDEV_PAD_SIZE, NULL, NULL, flags); 1127 1128 vdev_label_write(zio, vd, l, ub_abd, 1129 offsetof(vdev_label_t, vl_uberblock), 1130 VDEV_UBERBLOCK_RING, NULL, NULL, flags); 1131 } 1132 1133 error = zio_wait(zio); 1134 1135 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) { 1136 flags |= ZIO_FLAG_TRYHARD; 1137 goto retry; 1138 } 1139 1140 nvlist_free(label); 1141 abd_free(pad2); 1142 abd_free(ub_abd); 1143 abd_free(vp_abd); 1144 1145 /* 1146 * If this vdev hasn't been previously identified as a spare, then we 1147 * mark it as such only if a) we are labeling it as a spare, or b) it 1148 * exists as a spare elsewhere in the system. Do the same for 1149 * level 2 ARC devices. 1150 */ 1151 if (error == 0 && !vd->vdev_isspare && 1152 (reason == VDEV_LABEL_SPARE || 1153 spa_spare_exists(vd->vdev_guid, NULL, NULL))) 1154 spa_spare_add(vd); 1155 1156 if (error == 0 && !vd->vdev_isl2cache && 1157 (reason == VDEV_LABEL_L2CACHE || 1158 spa_l2cache_exists(vd->vdev_guid, NULL))) 1159 spa_l2cache_add(vd); 1160 1161 return (error); 1162 } 1163 1164 /* 1165 * ========================================================================== 1166 * uberblock load/sync 1167 * ========================================================================== 1168 */ 1169 1170 /* 1171 * Consider the following situation: txg is safely synced to disk. We've 1172 * written the first uberblock for txg + 1, and then we lose power. When we 1173 * come back up, we fail to see the uberblock for txg + 1 because, say, 1174 * it was on a mirrored device and the replica to which we wrote txg + 1 1175 * is now offline. If we then make some changes and sync txg + 1, and then 1176 * the missing replica comes back, then for a few seconds we'll have two 1177 * conflicting uberblocks on disk with the same txg. The solution is simple: 1178 * among uberblocks with equal txg, choose the one with the latest timestamp. 1179 */ 1180 static int 1181 vdev_uberblock_compare(const uberblock_t *ub1, const uberblock_t *ub2) 1182 { 1183 int cmp = TREE_CMP(ub1->ub_txg, ub2->ub_txg); 1184 1185 if (likely(cmp)) 1186 return (cmp); 1187 1188 cmp = TREE_CMP(ub1->ub_timestamp, ub2->ub_timestamp); 1189 if (likely(cmp)) 1190 return (cmp); 1191 1192 /* 1193 * If MMP_VALID(ub) && MMP_SEQ_VALID(ub) then the host has an MMP-aware 1194 * ZFS, e.g. zfsonlinux >= 0.7. 1195 * 1196 * If one ub has MMP and the other does not, they were written by 1197 * different hosts, which matters for MMP. So we treat no MMP/no SEQ as 1198 * a 0 value. 1199 * 1200 * Since timestamp and txg are the same if we get this far, either is 1201 * acceptable for importing the pool. 1202 */ 1203 unsigned int seq1 = 0; 1204 unsigned int seq2 = 0; 1205 1206 if (MMP_VALID(ub1) && MMP_SEQ_VALID(ub1)) 1207 seq1 = MMP_SEQ(ub1); 1208 1209 if (MMP_VALID(ub2) && MMP_SEQ_VALID(ub2)) 1210 seq2 = MMP_SEQ(ub2); 1211 1212 return (TREE_CMP(seq1, seq2)); 1213 } 1214 1215 struct ubl_cbdata { 1216 uberblock_t *ubl_ubbest; /* Best uberblock */ 1217 vdev_t *ubl_vd; /* vdev associated with the above */ 1218 }; 1219 1220 static void 1221 vdev_uberblock_load_done(zio_t *zio) 1222 { 1223 vdev_t *vd = zio->io_vd; 1224 spa_t *spa = zio->io_spa; 1225 zio_t *rio = zio->io_private; 1226 uberblock_t *ub = abd_to_buf(zio->io_abd); 1227 struct ubl_cbdata *cbp = rio->io_private; 1228 1229 ASSERT3U(zio->io_size, ==, VDEV_UBERBLOCK_SIZE(vd)); 1230 1231 if (zio->io_error == 0 && uberblock_verify(ub) == 0) { 1232 mutex_enter(&rio->io_lock); 1233 if (ub->ub_txg <= spa->spa_load_max_txg && 1234 vdev_uberblock_compare(ub, cbp->ubl_ubbest) > 0) { 1235 /* 1236 * Keep track of the vdev in which this uberblock 1237 * was found. We will use this information later 1238 * to obtain the config nvlist associated with 1239 * this uberblock. 1240 */ 1241 *cbp->ubl_ubbest = *ub; 1242 cbp->ubl_vd = vd; 1243 } 1244 mutex_exit(&rio->io_lock); 1245 } 1246 1247 abd_free(zio->io_abd); 1248 } 1249 1250 static void 1251 vdev_uberblock_load_impl(zio_t *zio, vdev_t *vd, int flags, 1252 struct ubl_cbdata *cbp) 1253 { 1254 for (int c = 0; c < vd->vdev_children; c++) 1255 vdev_uberblock_load_impl(zio, vd->vdev_child[c], flags, cbp); 1256 1257 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd)) { 1258 for (int l = 0; l < VDEV_LABELS; l++) { 1259 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) { 1260 vdev_label_read(zio, vd, l, 1261 abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), 1262 B_TRUE), VDEV_UBERBLOCK_OFFSET(vd, n), 1263 VDEV_UBERBLOCK_SIZE(vd), 1264 vdev_uberblock_load_done, zio, flags); 1265 } 1266 } 1267 } 1268 } 1269 1270 /* 1271 * Reads the 'best' uberblock from disk along with its associated 1272 * configuration. First, we read the uberblock array of each label of each 1273 * vdev, keeping track of the uberblock with the highest txg in each array. 1274 * Then, we read the configuration from the same vdev as the best uberblock. 1275 */ 1276 void 1277 vdev_uberblock_load(vdev_t *rvd, uberblock_t *ub, nvlist_t **config) 1278 { 1279 zio_t *zio; 1280 spa_t *spa = rvd->vdev_spa; 1281 struct ubl_cbdata cb; 1282 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 1283 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD; 1284 1285 ASSERT(ub); 1286 ASSERT(config); 1287 1288 bzero(ub, sizeof (uberblock_t)); 1289 *config = NULL; 1290 1291 cb.ubl_ubbest = ub; 1292 cb.ubl_vd = NULL; 1293 1294 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 1295 zio = zio_root(spa, NULL, &cb, flags); 1296 vdev_uberblock_load_impl(zio, rvd, flags, &cb); 1297 (void) zio_wait(zio); 1298 1299 /* 1300 * It's possible that the best uberblock was discovered on a label 1301 * that has a configuration which was written in a future txg. 1302 * Search all labels on this vdev to find the configuration that 1303 * matches the txg for our uberblock. 1304 */ 1305 if (cb.ubl_vd != NULL) { 1306 vdev_dbgmsg(cb.ubl_vd, "best uberblock found for spa %s. " 1307 "txg %llu", spa->spa_name, (u_longlong_t)ub->ub_txg); 1308 1309 *config = vdev_label_read_config(cb.ubl_vd, ub->ub_txg); 1310 if (*config == NULL && spa->spa_extreme_rewind) { 1311 vdev_dbgmsg(cb.ubl_vd, "failed to read label config. " 1312 "Trying again without txg restrictions."); 1313 *config = vdev_label_read_config(cb.ubl_vd, UINT64_MAX); 1314 } 1315 if (*config == NULL) { 1316 vdev_dbgmsg(cb.ubl_vd, "failed to read label config"); 1317 } 1318 } 1319 spa_config_exit(spa, SCL_ALL, FTAG); 1320 } 1321 1322 /* 1323 * On success, increment root zio's count of good writes. 1324 * We only get credit for writes to known-visible vdevs; see spa_vdev_add(). 1325 */ 1326 static void 1327 vdev_uberblock_sync_done(zio_t *zio) 1328 { 1329 uint64_t *good_writes = zio->io_private; 1330 1331 if (zio->io_error == 0 && zio->io_vd->vdev_top->vdev_ms_array != 0) 1332 atomic_inc_64(good_writes); 1333 } 1334 1335 /* 1336 * Write the uberblock to all labels of all leaves of the specified vdev. 1337 */ 1338 static void 1339 vdev_uberblock_sync(zio_t *zio, uint64_t *good_writes, 1340 uberblock_t *ub, vdev_t *vd, int flags) 1341 { 1342 for (uint64_t c = 0; c < vd->vdev_children; c++) { 1343 vdev_uberblock_sync(zio, good_writes, 1344 ub, vd->vdev_child[c], flags); 1345 } 1346 1347 if (!vd->vdev_ops->vdev_op_leaf) 1348 return; 1349 1350 if (!vdev_writeable(vd)) 1351 return; 1352 1353 int m = spa_multihost(vd->vdev_spa) ? MMP_BLOCKS_PER_LABEL : 0; 1354 int n = ub->ub_txg % (VDEV_UBERBLOCK_COUNT(vd) - m); 1355 1356 /* Copy the uberblock_t into the ABD */ 1357 abd_t *ub_abd = abd_alloc_for_io(VDEV_UBERBLOCK_SIZE(vd), B_TRUE); 1358 abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd)); 1359 abd_copy_from_buf(ub_abd, ub, sizeof (uberblock_t)); 1360 1361 for (int l = 0; l < VDEV_LABELS; l++) 1362 vdev_label_write(zio, vd, l, ub_abd, 1363 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd), 1364 vdev_uberblock_sync_done, good_writes, 1365 flags | ZIO_FLAG_DONT_PROPAGATE); 1366 1367 abd_free(ub_abd); 1368 } 1369 1370 /* Sync the uberblocks to all vdevs in svd[] */ 1371 int 1372 vdev_uberblock_sync_list(vdev_t **svd, int svdcount, uberblock_t *ub, int flags) 1373 { 1374 spa_t *spa = svd[0]->vdev_spa; 1375 zio_t *zio; 1376 uint64_t good_writes = 0; 1377 1378 zio = zio_root(spa, NULL, NULL, flags); 1379 1380 for (int v = 0; v < svdcount; v++) 1381 vdev_uberblock_sync(zio, &good_writes, ub, svd[v], flags); 1382 1383 (void) zio_wait(zio); 1384 1385 /* 1386 * Flush the uberblocks to disk. This ensures that the odd labels 1387 * are no longer needed (because the new uberblocks and the even 1388 * labels are safely on disk), so it is safe to overwrite them. 1389 */ 1390 zio = zio_root(spa, NULL, NULL, flags); 1391 1392 for (int v = 0; v < svdcount; v++) { 1393 if (vdev_writeable(svd[v])) { 1394 zio_flush(zio, svd[v]); 1395 } 1396 } 1397 1398 (void) zio_wait(zio); 1399 1400 return (good_writes >= 1 ? 0 : EIO); 1401 } 1402 1403 /* 1404 * On success, increment the count of good writes for our top-level vdev. 1405 */ 1406 static void 1407 vdev_label_sync_done(zio_t *zio) 1408 { 1409 uint64_t *good_writes = zio->io_private; 1410 1411 if (zio->io_error == 0) 1412 atomic_inc_64(good_writes); 1413 } 1414 1415 /* 1416 * If there weren't enough good writes, indicate failure to the parent. 1417 */ 1418 static void 1419 vdev_label_sync_top_done(zio_t *zio) 1420 { 1421 uint64_t *good_writes = zio->io_private; 1422 1423 if (*good_writes == 0) 1424 zio->io_error = SET_ERROR(EIO); 1425 1426 kmem_free(good_writes, sizeof (uint64_t)); 1427 } 1428 1429 /* 1430 * We ignore errors for log and cache devices, simply free the private data. 1431 */ 1432 static void 1433 vdev_label_sync_ignore_done(zio_t *zio) 1434 { 1435 kmem_free(zio->io_private, sizeof (uint64_t)); 1436 } 1437 1438 /* 1439 * Write all even or odd labels to all leaves of the specified vdev. 1440 */ 1441 static void 1442 vdev_label_sync(zio_t *zio, uint64_t *good_writes, 1443 vdev_t *vd, int l, uint64_t txg, int flags) 1444 { 1445 nvlist_t *label; 1446 vdev_phys_t *vp; 1447 abd_t *vp_abd; 1448 char *buf; 1449 size_t buflen; 1450 1451 for (int c = 0; c < vd->vdev_children; c++) { 1452 vdev_label_sync(zio, good_writes, 1453 vd->vdev_child[c], l, txg, flags); 1454 } 1455 1456 if (!vd->vdev_ops->vdev_op_leaf) 1457 return; 1458 1459 if (!vdev_writeable(vd)) 1460 return; 1461 1462 /* 1463 * Generate a label describing the top-level config to which we belong. 1464 */ 1465 label = spa_config_generate(vd->vdev_spa, vd, txg, B_FALSE); 1466 1467 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 1468 abd_zero(vp_abd, sizeof (vdev_phys_t)); 1469 vp = abd_to_buf(vp_abd); 1470 1471 buf = vp->vp_nvlist; 1472 buflen = sizeof (vp->vp_nvlist); 1473 1474 if (nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP) == 0) { 1475 for (; l < VDEV_LABELS; l += 2) { 1476 vdev_label_write(zio, vd, l, vp_abd, 1477 offsetof(vdev_label_t, vl_vdev_phys), 1478 sizeof (vdev_phys_t), 1479 vdev_label_sync_done, good_writes, 1480 flags | ZIO_FLAG_DONT_PROPAGATE); 1481 } 1482 } 1483 1484 abd_free(vp_abd); 1485 nvlist_free(label); 1486 } 1487 1488 int 1489 vdev_label_sync_list(spa_t *spa, int l, uint64_t txg, int flags) 1490 { 1491 list_t *dl = &spa->spa_config_dirty_list; 1492 vdev_t *vd; 1493 zio_t *zio; 1494 int error; 1495 1496 /* 1497 * Write the new labels to disk. 1498 */ 1499 zio = zio_root(spa, NULL, NULL, flags); 1500 1501 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) { 1502 uint64_t *good_writes = kmem_zalloc(sizeof (uint64_t), 1503 KM_SLEEP); 1504 1505 ASSERT(!vd->vdev_ishole); 1506 1507 zio_t *vio = zio_null(zio, spa, NULL, 1508 (vd->vdev_islog || vd->vdev_aux != NULL) ? 1509 vdev_label_sync_ignore_done : vdev_label_sync_top_done, 1510 good_writes, flags); 1511 vdev_label_sync(vio, good_writes, vd, l, txg, flags); 1512 zio_nowait(vio); 1513 } 1514 1515 error = zio_wait(zio); 1516 1517 /* 1518 * Flush the new labels to disk. 1519 */ 1520 zio = zio_root(spa, NULL, NULL, flags); 1521 1522 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) 1523 zio_flush(zio, vd); 1524 1525 (void) zio_wait(zio); 1526 1527 return (error); 1528 } 1529 1530 /* 1531 * Sync the uberblock and any changes to the vdev configuration. 1532 * 1533 * The order of operations is carefully crafted to ensure that 1534 * if the system panics or loses power at any time, the state on disk 1535 * is still transactionally consistent. The in-line comments below 1536 * describe the failure semantics at each stage. 1537 * 1538 * Moreover, vdev_config_sync() is designed to be idempotent: if it fails 1539 * at any time, you can just call it again, and it will resume its work. 1540 */ 1541 int 1542 vdev_config_sync(vdev_t **svd, int svdcount, uint64_t txg) 1543 { 1544 spa_t *spa = svd[0]->vdev_spa; 1545 uberblock_t *ub = &spa->spa_uberblock; 1546 int error = 0; 1547 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; 1548 1549 ASSERT(svdcount != 0); 1550 retry: 1551 /* 1552 * Normally, we don't want to try too hard to write every label and 1553 * uberblock. If there is a flaky disk, we don't want the rest of the 1554 * sync process to block while we retry. But if we can't write a 1555 * single label out, we should retry with ZIO_FLAG_TRYHARD before 1556 * bailing out and declaring the pool faulted. 1557 */ 1558 if (error != 0) { 1559 if ((flags & ZIO_FLAG_TRYHARD) != 0) 1560 return (error); 1561 flags |= ZIO_FLAG_TRYHARD; 1562 } 1563 1564 ASSERT(ub->ub_txg <= txg); 1565 1566 /* 1567 * If this isn't a resync due to I/O errors, 1568 * and nothing changed in this transaction group, 1569 * and the vdev configuration hasn't changed, 1570 * then there's nothing to do. 1571 */ 1572 if (ub->ub_txg < txg) { 1573 boolean_t changed = uberblock_update(ub, spa->spa_root_vdev, 1574 txg, spa->spa_mmp.mmp_delay); 1575 1576 if (!changed && list_is_empty(&spa->spa_config_dirty_list)) 1577 return (0); 1578 } 1579 1580 if (txg > spa_freeze_txg(spa)) 1581 return (0); 1582 1583 ASSERT(txg <= spa->spa_final_txg); 1584 1585 /* 1586 * Flush the write cache of every disk that's been written to 1587 * in this transaction group. This ensures that all blocks 1588 * written in this txg will be committed to stable storage 1589 * before any uberblock that references them. 1590 */ 1591 zio_t *zio = zio_root(spa, NULL, NULL, flags); 1592 1593 for (vdev_t *vd = 1594 txg_list_head(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)); vd != NULL; 1595 vd = txg_list_next(&spa->spa_vdev_txg_list, vd, TXG_CLEAN(txg))) 1596 zio_flush(zio, vd); 1597 1598 (void) zio_wait(zio); 1599 1600 /* 1601 * Sync out the even labels (L0, L2) for every dirty vdev. If the 1602 * system dies in the middle of this process, that's OK: all of the 1603 * even labels that made it to disk will be newer than any uberblock, 1604 * and will therefore be considered invalid. The odd labels (L1, L3), 1605 * which have not yet been touched, will still be valid. We flush 1606 * the new labels to disk to ensure that all even-label updates 1607 * are committed to stable storage before the uberblock update. 1608 */ 1609 if ((error = vdev_label_sync_list(spa, 0, txg, flags)) != 0) { 1610 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 1611 zfs_dbgmsg("vdev_label_sync_list() returned error %d " 1612 "for pool '%s' when syncing out the even labels " 1613 "of dirty vdevs", error, spa_name(spa)); 1614 } 1615 goto retry; 1616 } 1617 1618 /* 1619 * Sync the uberblocks to all vdevs in svd[]. 1620 * If the system dies in the middle of this step, there are two cases 1621 * to consider, and the on-disk state is consistent either way: 1622 * 1623 * (1) If none of the new uberblocks made it to disk, then the 1624 * previous uberblock will be the newest, and the odd labels 1625 * (which had not yet been touched) will be valid with respect 1626 * to that uberblock. 1627 * 1628 * (2) If one or more new uberblocks made it to disk, then they 1629 * will be the newest, and the even labels (which had all 1630 * been successfully committed) will be valid with respect 1631 * to the new uberblocks. 1632 */ 1633 if ((error = vdev_uberblock_sync_list(svd, svdcount, ub, flags)) != 0) { 1634 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 1635 zfs_dbgmsg("vdev_uberblock_sync_list() returned error " 1636 "%d for pool '%s'", error, spa_name(spa)); 1637 } 1638 goto retry; 1639 } 1640 1641 if (spa_multihost(spa)) 1642 mmp_update_uberblock(spa, ub); 1643 1644 /* 1645 * Sync out odd labels for every dirty vdev. If the system dies 1646 * in the middle of this process, the even labels and the new 1647 * uberblocks will suffice to open the pool. The next time 1648 * the pool is opened, the first thing we'll do -- before any 1649 * user data is modified -- is mark every vdev dirty so that 1650 * all labels will be brought up to date. We flush the new labels 1651 * to disk to ensure that all odd-label updates are committed to 1652 * stable storage before the next transaction group begins. 1653 */ 1654 if ((error = vdev_label_sync_list(spa, 1, txg, flags)) != 0) { 1655 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 1656 zfs_dbgmsg("vdev_label_sync_list() returned error %d " 1657 "for pool '%s' when syncing out the odd labels of " 1658 "dirty vdevs", error, spa_name(spa)); 1659 } 1660 goto retry; 1661 } 1662 1663 return (0); 1664 } 1665