1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or https://opensource.org/licenses/CDDL-1.0. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2012, 2020 by Delphix. All rights reserved. 25 * Copyright (c) 2017, Intel Corporation. 26 */ 27 28 /* 29 * Virtual Device Labels 30 * --------------------- 31 * 32 * The vdev label serves several distinct purposes: 33 * 34 * 1. Uniquely identify this device as part of a ZFS pool and confirm its 35 * identity within the pool. 36 * 37 * 2. Verify that all the devices given in a configuration are present 38 * within the pool. 39 * 40 * 3. Determine the uberblock for the pool. 41 * 42 * 4. In case of an import operation, determine the configuration of the 43 * toplevel vdev of which it is a part. 44 * 45 * 5. If an import operation cannot find all the devices in the pool, 46 * provide enough information to the administrator to determine which 47 * devices are missing. 48 * 49 * It is important to note that while the kernel is responsible for writing the 50 * label, it only consumes the information in the first three cases. The 51 * latter information is only consumed in userland when determining the 52 * configuration to import a pool. 53 * 54 * 55 * Label Organization 56 * ------------------ 57 * 58 * Before describing the contents of the label, it's important to understand how 59 * the labels are written and updated with respect to the uberblock. 60 * 61 * When the pool configuration is altered, either because it was newly created 62 * or a device was added, we want to update all the labels such that we can deal 63 * with fatal failure at any point. To this end, each disk has two labels which 64 * are updated before and after the uberblock is synced. Assuming we have 65 * labels and an uberblock with the following transaction groups: 66 * 67 * L1 UB L2 68 * +------+ +------+ +------+ 69 * | | | | | | 70 * | t10 | | t10 | | t10 | 71 * | | | | | | 72 * +------+ +------+ +------+ 73 * 74 * In this stable state, the labels and the uberblock were all updated within 75 * the same transaction group (10). Each label is mirrored and checksummed, so 76 * that we can detect when we fail partway through writing the label. 77 * 78 * In order to identify which labels are valid, the labels are written in the 79 * following manner: 80 * 81 * 1. For each vdev, update 'L1' to the new label 82 * 2. Update the uberblock 83 * 3. For each vdev, update 'L2' to the new label 84 * 85 * Given arbitrary failure, we can determine the correct label to use based on 86 * the transaction group. If we fail after updating L1 but before updating the 87 * UB, we will notice that L1's transaction group is greater than the uberblock, 88 * so L2 must be valid. If we fail after writing the uberblock but before 89 * writing L2, we will notice that L2's transaction group is less than L1, and 90 * therefore L1 is valid. 91 * 92 * Another added complexity is that not every label is updated when the config 93 * is synced. If we add a single device, we do not want to have to re-write 94 * every label for every device in the pool. This means that both L1 and L2 may 95 * be older than the pool uberblock, because the necessary information is stored 96 * on another vdev. 97 * 98 * 99 * On-disk Format 100 * -------------- 101 * 102 * The vdev label consists of two distinct parts, and is wrapped within the 103 * vdev_label_t structure. The label includes 8k of padding to permit legacy 104 * VTOC disk labels, but is otherwise ignored. 105 * 106 * The first half of the label is a packed nvlist which contains pool wide 107 * properties, per-vdev properties, and configuration information. It is 108 * described in more detail below. 109 * 110 * The latter half of the label consists of a redundant array of uberblocks. 111 * These uberblocks are updated whenever a transaction group is committed, 112 * or when the configuration is updated. When a pool is loaded, we scan each 113 * vdev for the 'best' uberblock. 114 * 115 * 116 * Configuration Information 117 * ------------------------- 118 * 119 * The nvlist describing the pool and vdev contains the following elements: 120 * 121 * version ZFS on-disk version 122 * name Pool name 123 * state Pool state 124 * txg Transaction group in which this label was written 125 * pool_guid Unique identifier for this pool 126 * vdev_tree An nvlist describing vdev tree. 127 * features_for_read 128 * An nvlist of the features necessary for reading the MOS. 129 * 130 * Each leaf device label also contains the following: 131 * 132 * top_guid Unique ID for top-level vdev in which this is contained 133 * guid Unique ID for the leaf vdev 134 * 135 * The 'vs' configuration follows the format described in 'spa_config.c'. 136 */ 137 138 #include <sys/zfs_context.h> 139 #include <sys/spa.h> 140 #include <sys/spa_impl.h> 141 #include <sys/dmu.h> 142 #include <sys/zap.h> 143 #include <sys/vdev.h> 144 #include <sys/vdev_impl.h> 145 #include <sys/vdev_raidz.h> 146 #include <sys/vdev_draid.h> 147 #include <sys/uberblock_impl.h> 148 #include <sys/metaslab.h> 149 #include <sys/metaslab_impl.h> 150 #include <sys/zio.h> 151 #include <sys/dsl_scan.h> 152 #include <sys/abd.h> 153 #include <sys/fs/zfs.h> 154 #include <sys/byteorder.h> 155 #include <sys/zfs_bootenv.h> 156 157 /* 158 * Basic routines to read and write from a vdev label. 159 * Used throughout the rest of this file. 160 */ 161 uint64_t 162 vdev_label_offset(uint64_t psize, int l, uint64_t offset) 163 { 164 ASSERT(offset < sizeof (vdev_label_t)); 165 ASSERT(P2PHASE_TYPED(psize, sizeof (vdev_label_t), uint64_t) == 0); 166 167 return (offset + l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ? 168 0 : psize - VDEV_LABELS * sizeof (vdev_label_t))); 169 } 170 171 /* 172 * Returns back the vdev label associated with the passed in offset. 173 */ 174 int 175 vdev_label_number(uint64_t psize, uint64_t offset) 176 { 177 int l; 178 179 if (offset >= psize - VDEV_LABEL_END_SIZE) { 180 offset -= psize - VDEV_LABEL_END_SIZE; 181 offset += (VDEV_LABELS / 2) * sizeof (vdev_label_t); 182 } 183 l = offset / sizeof (vdev_label_t); 184 return (l < VDEV_LABELS ? l : -1); 185 } 186 187 static void 188 vdev_label_read(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset, 189 uint64_t size, zio_done_func_t *done, void *private, int flags) 190 { 191 ASSERT( 192 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE || 193 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE); 194 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER); 195 196 zio_nowait(zio_read_phys(zio, vd, 197 vdev_label_offset(vd->vdev_psize, l, offset), 198 size, buf, ZIO_CHECKSUM_LABEL, done, private, 199 ZIO_PRIORITY_SYNC_READ, flags, B_TRUE)); 200 } 201 202 void 203 vdev_label_write(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset, 204 uint64_t size, zio_done_func_t *done, void *private, int flags) 205 { 206 ASSERT( 207 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE || 208 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE); 209 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER); 210 211 zio_nowait(zio_write_phys(zio, vd, 212 vdev_label_offset(vd->vdev_psize, l, offset), 213 size, buf, ZIO_CHECKSUM_LABEL, done, private, 214 ZIO_PRIORITY_SYNC_WRITE, flags, B_TRUE)); 215 } 216 217 /* 218 * Generate the nvlist representing this vdev's stats 219 */ 220 void 221 vdev_config_generate_stats(vdev_t *vd, nvlist_t *nv) 222 { 223 nvlist_t *nvx; 224 vdev_stat_t *vs; 225 vdev_stat_ex_t *vsx; 226 227 vs = kmem_alloc(sizeof (*vs), KM_SLEEP); 228 vsx = kmem_alloc(sizeof (*vsx), KM_SLEEP); 229 230 vdev_get_stats_ex(vd, vs, vsx); 231 fnvlist_add_uint64_array(nv, ZPOOL_CONFIG_VDEV_STATS, 232 (uint64_t *)vs, sizeof (*vs) / sizeof (uint64_t)); 233 234 /* 235 * Add extended stats into a special extended stats nvlist. This keeps 236 * all the extended stats nicely grouped together. The extended stats 237 * nvlist is then added to the main nvlist. 238 */ 239 nvx = fnvlist_alloc(); 240 241 /* ZIOs in flight to disk */ 242 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_ACTIVE_QUEUE, 243 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_READ]); 244 245 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_ACTIVE_QUEUE, 246 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_WRITE]); 247 248 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_ACTIVE_QUEUE, 249 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_READ]); 250 251 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_ACTIVE_QUEUE, 252 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_WRITE]); 253 254 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_ACTIVE_QUEUE, 255 vsx->vsx_active_queue[ZIO_PRIORITY_SCRUB]); 256 257 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_ACTIVE_QUEUE, 258 vsx->vsx_active_queue[ZIO_PRIORITY_TRIM]); 259 260 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_REBUILD_ACTIVE_QUEUE, 261 vsx->vsx_active_queue[ZIO_PRIORITY_REBUILD]); 262 263 /* ZIOs pending */ 264 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_PEND_QUEUE, 265 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_READ]); 266 267 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_PEND_QUEUE, 268 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_WRITE]); 269 270 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_PEND_QUEUE, 271 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_READ]); 272 273 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_PEND_QUEUE, 274 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_WRITE]); 275 276 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_PEND_QUEUE, 277 vsx->vsx_pend_queue[ZIO_PRIORITY_SCRUB]); 278 279 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_PEND_QUEUE, 280 vsx->vsx_pend_queue[ZIO_PRIORITY_TRIM]); 281 282 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_REBUILD_PEND_QUEUE, 283 vsx->vsx_pend_queue[ZIO_PRIORITY_REBUILD]); 284 285 /* Histograms */ 286 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_R_LAT_HISTO, 287 vsx->vsx_total_histo[ZIO_TYPE_READ], 288 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_READ])); 289 290 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_W_LAT_HISTO, 291 vsx->vsx_total_histo[ZIO_TYPE_WRITE], 292 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_WRITE])); 293 294 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_R_LAT_HISTO, 295 vsx->vsx_disk_histo[ZIO_TYPE_READ], 296 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_READ])); 297 298 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_W_LAT_HISTO, 299 vsx->vsx_disk_histo[ZIO_TYPE_WRITE], 300 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_WRITE])); 301 302 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_LAT_HISTO, 303 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ], 304 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ])); 305 306 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_LAT_HISTO, 307 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE], 308 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE])); 309 310 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_LAT_HISTO, 311 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ], 312 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ])); 313 314 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_LAT_HISTO, 315 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE], 316 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE])); 317 318 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SCRUB_LAT_HISTO, 319 vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB], 320 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB])); 321 322 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TRIM_LAT_HISTO, 323 vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM], 324 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM])); 325 326 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_REBUILD_LAT_HISTO, 327 vsx->vsx_queue_histo[ZIO_PRIORITY_REBUILD], 328 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_REBUILD])); 329 330 /* Request sizes */ 331 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_R_HISTO, 332 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ], 333 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ])); 334 335 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_W_HISTO, 336 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE], 337 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE])); 338 339 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_R_HISTO, 340 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ], 341 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ])); 342 343 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_W_HISTO, 344 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE], 345 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE])); 346 347 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_SCRUB_HISTO, 348 vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB], 349 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB])); 350 351 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_TRIM_HISTO, 352 vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM], 353 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM])); 354 355 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_REBUILD_HISTO, 356 vsx->vsx_ind_histo[ZIO_PRIORITY_REBUILD], 357 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_REBUILD])); 358 359 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_R_HISTO, 360 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ], 361 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ])); 362 363 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_W_HISTO, 364 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE], 365 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE])); 366 367 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_R_HISTO, 368 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ], 369 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ])); 370 371 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_W_HISTO, 372 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE], 373 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE])); 374 375 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_SCRUB_HISTO, 376 vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB], 377 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB])); 378 379 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_TRIM_HISTO, 380 vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM], 381 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM])); 382 383 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_REBUILD_HISTO, 384 vsx->vsx_agg_histo[ZIO_PRIORITY_REBUILD], 385 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_REBUILD])); 386 387 /* IO delays */ 388 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SLOW_IOS, vs->vs_slow_ios); 389 390 /* Add extended stats nvlist to main nvlist */ 391 fnvlist_add_nvlist(nv, ZPOOL_CONFIG_VDEV_STATS_EX, nvx); 392 393 fnvlist_free(nvx); 394 kmem_free(vs, sizeof (*vs)); 395 kmem_free(vsx, sizeof (*vsx)); 396 } 397 398 static void 399 root_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl) 400 { 401 spa_t *spa = vd->vdev_spa; 402 403 if (vd != spa->spa_root_vdev) 404 return; 405 406 /* provide either current or previous scan information */ 407 pool_scan_stat_t ps; 408 if (spa_scan_get_stats(spa, &ps) == 0) { 409 fnvlist_add_uint64_array(nvl, 410 ZPOOL_CONFIG_SCAN_STATS, (uint64_t *)&ps, 411 sizeof (pool_scan_stat_t) / sizeof (uint64_t)); 412 } 413 414 pool_removal_stat_t prs; 415 if (spa_removal_get_stats(spa, &prs) == 0) { 416 fnvlist_add_uint64_array(nvl, 417 ZPOOL_CONFIG_REMOVAL_STATS, (uint64_t *)&prs, 418 sizeof (prs) / sizeof (uint64_t)); 419 } 420 421 pool_checkpoint_stat_t pcs; 422 if (spa_checkpoint_get_stats(spa, &pcs) == 0) { 423 fnvlist_add_uint64_array(nvl, 424 ZPOOL_CONFIG_CHECKPOINT_STATS, (uint64_t *)&pcs, 425 sizeof (pcs) / sizeof (uint64_t)); 426 } 427 428 pool_raidz_expand_stat_t pres; 429 if (spa_raidz_expand_get_stats(spa, &pres) == 0) { 430 fnvlist_add_uint64_array(nvl, 431 ZPOOL_CONFIG_RAIDZ_EXPAND_STATS, (uint64_t *)&pres, 432 sizeof (pres) / sizeof (uint64_t)); 433 } 434 } 435 436 static void 437 top_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl) 438 { 439 if (vd == vd->vdev_top) { 440 vdev_rebuild_stat_t vrs; 441 if (vdev_rebuild_get_stats(vd, &vrs) == 0) { 442 fnvlist_add_uint64_array(nvl, 443 ZPOOL_CONFIG_REBUILD_STATS, (uint64_t *)&vrs, 444 sizeof (vrs) / sizeof (uint64_t)); 445 } 446 } 447 } 448 449 /* 450 * Generate the nvlist representing this vdev's config. 451 */ 452 nvlist_t * 453 vdev_config_generate(spa_t *spa, vdev_t *vd, boolean_t getstats, 454 vdev_config_flag_t flags) 455 { 456 nvlist_t *nv = NULL; 457 vdev_indirect_config_t *vic = &vd->vdev_indirect_config; 458 459 nv = fnvlist_alloc(); 460 461 fnvlist_add_string(nv, ZPOOL_CONFIG_TYPE, vd->vdev_ops->vdev_op_type); 462 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE))) 463 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ID, vd->vdev_id); 464 fnvlist_add_uint64(nv, ZPOOL_CONFIG_GUID, vd->vdev_guid); 465 466 if (vd->vdev_path != NULL) 467 fnvlist_add_string(nv, ZPOOL_CONFIG_PATH, vd->vdev_path); 468 469 if (vd->vdev_devid != NULL) 470 fnvlist_add_string(nv, ZPOOL_CONFIG_DEVID, vd->vdev_devid); 471 472 if (vd->vdev_physpath != NULL) 473 fnvlist_add_string(nv, ZPOOL_CONFIG_PHYS_PATH, 474 vd->vdev_physpath); 475 476 if (vd->vdev_enc_sysfs_path != NULL) 477 fnvlist_add_string(nv, ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH, 478 vd->vdev_enc_sysfs_path); 479 480 if (vd->vdev_fru != NULL) 481 fnvlist_add_string(nv, ZPOOL_CONFIG_FRU, vd->vdev_fru); 482 483 if (vd->vdev_ops->vdev_op_config_generate != NULL) 484 vd->vdev_ops->vdev_op_config_generate(vd, nv); 485 486 if (vd->vdev_wholedisk != -1ULL) { 487 fnvlist_add_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK, 488 vd->vdev_wholedisk); 489 } 490 491 if (vd->vdev_not_present && !(flags & VDEV_CONFIG_MISSING)) 492 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NOT_PRESENT, 1); 493 494 if (vd->vdev_isspare) 495 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_SPARE, 1); 496 497 if (flags & VDEV_CONFIG_L2CACHE) 498 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASHIFT, vd->vdev_ashift); 499 500 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE)) && 501 vd == vd->vdev_top) { 502 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_ARRAY, 503 vd->vdev_ms_array); 504 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_SHIFT, 505 vd->vdev_ms_shift); 506 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASHIFT, vd->vdev_ashift); 507 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASIZE, 508 vd->vdev_asize); 509 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_LOG, vd->vdev_islog); 510 if (vd->vdev_noalloc) { 511 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NONALLOCATING, 512 vd->vdev_noalloc); 513 } 514 515 /* 516 * Slog devices are removed synchronously so don't 517 * persist the vdev_removing flag to the label. 518 */ 519 if (vd->vdev_removing && !vd->vdev_islog) { 520 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVING, 521 vd->vdev_removing); 522 } 523 524 /* zpool command expects alloc class data */ 525 if (getstats && vd->vdev_alloc_bias != VDEV_BIAS_NONE) { 526 const char *bias = NULL; 527 528 switch (vd->vdev_alloc_bias) { 529 case VDEV_BIAS_LOG: 530 bias = VDEV_ALLOC_BIAS_LOG; 531 break; 532 case VDEV_BIAS_SPECIAL: 533 bias = VDEV_ALLOC_BIAS_SPECIAL; 534 break; 535 case VDEV_BIAS_DEDUP: 536 bias = VDEV_ALLOC_BIAS_DEDUP; 537 break; 538 default: 539 ASSERT3U(vd->vdev_alloc_bias, ==, 540 VDEV_BIAS_NONE); 541 } 542 fnvlist_add_string(nv, ZPOOL_CONFIG_ALLOCATION_BIAS, 543 bias); 544 } 545 } 546 547 if (vd->vdev_dtl_sm != NULL) { 548 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DTL, 549 space_map_object(vd->vdev_dtl_sm)); 550 } 551 552 if (vic->vic_mapping_object != 0) { 553 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_OBJECT, 554 vic->vic_mapping_object); 555 } 556 557 if (vic->vic_births_object != 0) { 558 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_BIRTHS, 559 vic->vic_births_object); 560 } 561 562 if (vic->vic_prev_indirect_vdev != UINT64_MAX) { 563 fnvlist_add_uint64(nv, ZPOOL_CONFIG_PREV_INDIRECT_VDEV, 564 vic->vic_prev_indirect_vdev); 565 } 566 567 if (vd->vdev_crtxg) 568 fnvlist_add_uint64(nv, ZPOOL_CONFIG_CREATE_TXG, vd->vdev_crtxg); 569 570 if (vd->vdev_expansion_time) 571 fnvlist_add_uint64(nv, ZPOOL_CONFIG_EXPANSION_TIME, 572 vd->vdev_expansion_time); 573 574 if (flags & VDEV_CONFIG_MOS) { 575 if (vd->vdev_leaf_zap != 0) { 576 ASSERT(vd->vdev_ops->vdev_op_leaf); 577 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_LEAF_ZAP, 578 vd->vdev_leaf_zap); 579 } 580 581 if (vd->vdev_top_zap != 0) { 582 ASSERT(vd == vd->vdev_top); 583 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_TOP_ZAP, 584 vd->vdev_top_zap); 585 } 586 587 if (vd->vdev_ops == &vdev_root_ops && vd->vdev_root_zap != 0 && 588 spa_feature_is_active(vd->vdev_spa, SPA_FEATURE_AVZ_V2)) { 589 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_ROOT_ZAP, 590 vd->vdev_root_zap); 591 } 592 593 if (vd->vdev_resilver_deferred) { 594 ASSERT(vd->vdev_ops->vdev_op_leaf); 595 ASSERT(spa->spa_resilver_deferred); 596 fnvlist_add_boolean(nv, ZPOOL_CONFIG_RESILVER_DEFER); 597 } 598 } 599 600 if (getstats) { 601 vdev_config_generate_stats(vd, nv); 602 603 root_vdev_actions_getprogress(vd, nv); 604 top_vdev_actions_getprogress(vd, nv); 605 606 /* 607 * Note: this can be called from open context 608 * (spa_get_stats()), so we need the rwlock to prevent 609 * the mapping from being changed by condensing. 610 */ 611 rw_enter(&vd->vdev_indirect_rwlock, RW_READER); 612 if (vd->vdev_indirect_mapping != NULL) { 613 ASSERT(vd->vdev_indirect_births != NULL); 614 vdev_indirect_mapping_t *vim = 615 vd->vdev_indirect_mapping; 616 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE, 617 vdev_indirect_mapping_size(vim)); 618 } 619 rw_exit(&vd->vdev_indirect_rwlock); 620 if (vd->vdev_mg != NULL && 621 vd->vdev_mg->mg_fragmentation != ZFS_FRAG_INVALID) { 622 /* 623 * Compute approximately how much memory would be used 624 * for the indirect mapping if this device were to 625 * be removed. 626 * 627 * Note: If the frag metric is invalid, then not 628 * enough metaslabs have been converted to have 629 * histograms. 630 */ 631 uint64_t seg_count = 0; 632 uint64_t to_alloc = vd->vdev_stat.vs_alloc; 633 634 /* 635 * There are the same number of allocated segments 636 * as free segments, so we will have at least one 637 * entry per free segment. However, small free 638 * segments (smaller than vdev_removal_max_span) 639 * will be combined with adjacent allocated segments 640 * as a single mapping. 641 */ 642 for (int i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) { 643 if (i + 1 < highbit64(vdev_removal_max_span) 644 - 1) { 645 to_alloc += 646 vd->vdev_mg->mg_histogram[i] << 647 (i + 1); 648 } else { 649 seg_count += 650 vd->vdev_mg->mg_histogram[i]; 651 } 652 } 653 654 /* 655 * The maximum length of a mapping is 656 * zfs_remove_max_segment, so we need at least one entry 657 * per zfs_remove_max_segment of allocated data. 658 */ 659 seg_count += to_alloc / spa_remove_max_segment(spa); 660 661 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE, 662 seg_count * 663 sizeof (vdev_indirect_mapping_entry_phys_t)); 664 } 665 } 666 667 if (!vd->vdev_ops->vdev_op_leaf) { 668 nvlist_t **child; 669 uint64_t c; 670 671 ASSERT(!vd->vdev_ishole); 672 673 child = kmem_alloc(vd->vdev_children * sizeof (nvlist_t *), 674 KM_SLEEP); 675 676 for (c = 0; c < vd->vdev_children; c++) { 677 child[c] = vdev_config_generate(spa, vd->vdev_child[c], 678 getstats, flags); 679 } 680 681 fnvlist_add_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN, 682 (const nvlist_t * const *)child, vd->vdev_children); 683 684 for (c = 0; c < vd->vdev_children; c++) 685 nvlist_free(child[c]); 686 687 kmem_free(child, vd->vdev_children * sizeof (nvlist_t *)); 688 689 } else { 690 const char *aux = NULL; 691 692 if (vd->vdev_offline && !vd->vdev_tmpoffline) 693 fnvlist_add_uint64(nv, ZPOOL_CONFIG_OFFLINE, B_TRUE); 694 if (vd->vdev_resilver_txg != 0) 695 fnvlist_add_uint64(nv, ZPOOL_CONFIG_RESILVER_TXG, 696 vd->vdev_resilver_txg); 697 if (vd->vdev_rebuild_txg != 0) 698 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REBUILD_TXG, 699 vd->vdev_rebuild_txg); 700 if (vd->vdev_faulted) 701 fnvlist_add_uint64(nv, ZPOOL_CONFIG_FAULTED, B_TRUE); 702 if (vd->vdev_degraded) 703 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DEGRADED, B_TRUE); 704 if (vd->vdev_removed) 705 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVED, B_TRUE); 706 if (vd->vdev_unspare) 707 fnvlist_add_uint64(nv, ZPOOL_CONFIG_UNSPARE, B_TRUE); 708 if (vd->vdev_ishole) 709 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_HOLE, B_TRUE); 710 711 /* Set the reason why we're FAULTED/DEGRADED. */ 712 switch (vd->vdev_stat.vs_aux) { 713 case VDEV_AUX_ERR_EXCEEDED: 714 aux = "err_exceeded"; 715 break; 716 717 case VDEV_AUX_EXTERNAL: 718 aux = "external"; 719 break; 720 } 721 722 if (aux != NULL && !vd->vdev_tmpoffline) { 723 fnvlist_add_string(nv, ZPOOL_CONFIG_AUX_STATE, aux); 724 } else { 725 /* 726 * We're healthy - clear any previous AUX_STATE values. 727 */ 728 if (nvlist_exists(nv, ZPOOL_CONFIG_AUX_STATE)) 729 nvlist_remove_all(nv, ZPOOL_CONFIG_AUX_STATE); 730 } 731 732 if (vd->vdev_splitting && vd->vdev_orig_guid != 0LL) { 733 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ORIG_GUID, 734 vd->vdev_orig_guid); 735 } 736 } 737 738 return (nv); 739 } 740 741 /* 742 * Generate a view of the top-level vdevs. If we currently have holes 743 * in the namespace, then generate an array which contains a list of holey 744 * vdevs. Additionally, add the number of top-level children that currently 745 * exist. 746 */ 747 void 748 vdev_top_config_generate(spa_t *spa, nvlist_t *config) 749 { 750 vdev_t *rvd = spa->spa_root_vdev; 751 uint64_t *array; 752 uint_t c, idx; 753 754 array = kmem_alloc(rvd->vdev_children * sizeof (uint64_t), KM_SLEEP); 755 756 for (c = 0, idx = 0; c < rvd->vdev_children; c++) { 757 vdev_t *tvd = rvd->vdev_child[c]; 758 759 if (tvd->vdev_ishole) { 760 array[idx++] = c; 761 } 762 } 763 764 if (idx) { 765 VERIFY(nvlist_add_uint64_array(config, ZPOOL_CONFIG_HOLE_ARRAY, 766 array, idx) == 0); 767 } 768 769 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN, 770 rvd->vdev_children) == 0); 771 772 kmem_free(array, rvd->vdev_children * sizeof (uint64_t)); 773 } 774 775 /* 776 * Returns the configuration from the label of the given vdev. For vdevs 777 * which don't have a txg value stored on their label (i.e. spares/cache) 778 * or have not been completely initialized (txg = 0) just return 779 * the configuration from the first valid label we find. Otherwise, 780 * find the most up-to-date label that does not exceed the specified 781 * 'txg' value. 782 */ 783 nvlist_t * 784 vdev_label_read_config(vdev_t *vd, uint64_t txg) 785 { 786 spa_t *spa = vd->vdev_spa; 787 nvlist_t *config = NULL; 788 vdev_phys_t *vp[VDEV_LABELS]; 789 abd_t *vp_abd[VDEV_LABELS]; 790 zio_t *zio[VDEV_LABELS]; 791 uint64_t best_txg = 0; 792 uint64_t label_txg = 0; 793 int error = 0; 794 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 795 ZIO_FLAG_SPECULATIVE; 796 797 ASSERT(vd->vdev_validate_thread == curthread || 798 spa_config_held(spa, SCL_STATE_ALL, RW_WRITER) == SCL_STATE_ALL); 799 800 if (!vdev_readable(vd)) 801 return (NULL); 802 803 /* 804 * The label for a dRAID distributed spare is not stored on disk. 805 * Instead it is generated when needed which allows us to bypass 806 * the pipeline when reading the config from the label. 807 */ 808 if (vd->vdev_ops == &vdev_draid_spare_ops) 809 return (vdev_draid_read_config_spare(vd)); 810 811 for (int l = 0; l < VDEV_LABELS; l++) { 812 vp_abd[l] = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 813 vp[l] = abd_to_buf(vp_abd[l]); 814 } 815 816 retry: 817 for (int l = 0; l < VDEV_LABELS; l++) { 818 zio[l] = zio_root(spa, NULL, NULL, flags); 819 820 vdev_label_read(zio[l], vd, l, vp_abd[l], 821 offsetof(vdev_label_t, vl_vdev_phys), sizeof (vdev_phys_t), 822 NULL, NULL, flags); 823 } 824 for (int l = 0; l < VDEV_LABELS; l++) { 825 nvlist_t *label = NULL; 826 827 if (zio_wait(zio[l]) == 0 && 828 nvlist_unpack(vp[l]->vp_nvlist, sizeof (vp[l]->vp_nvlist), 829 &label, 0) == 0) { 830 /* 831 * Auxiliary vdevs won't have txg values in their 832 * labels and newly added vdevs may not have been 833 * completely initialized so just return the 834 * configuration from the first valid label we 835 * encounter. 836 */ 837 error = nvlist_lookup_uint64(label, 838 ZPOOL_CONFIG_POOL_TXG, &label_txg); 839 if ((error || label_txg == 0) && !config) { 840 config = label; 841 for (l++; l < VDEV_LABELS; l++) 842 zio_wait(zio[l]); 843 break; 844 } else if (label_txg <= txg && label_txg > best_txg) { 845 best_txg = label_txg; 846 nvlist_free(config); 847 config = fnvlist_dup(label); 848 } 849 } 850 851 if (label != NULL) { 852 nvlist_free(label); 853 label = NULL; 854 } 855 } 856 857 if (config == NULL && !(flags & ZIO_FLAG_TRYHARD)) { 858 flags |= ZIO_FLAG_TRYHARD; 859 goto retry; 860 } 861 862 /* 863 * We found a valid label but it didn't pass txg restrictions. 864 */ 865 if (config == NULL && label_txg != 0) { 866 vdev_dbgmsg(vd, "label discarded as txg is too large " 867 "(%llu > %llu)", (u_longlong_t)label_txg, 868 (u_longlong_t)txg); 869 } 870 871 for (int l = 0; l < VDEV_LABELS; l++) { 872 abd_free(vp_abd[l]); 873 } 874 875 return (config); 876 } 877 878 /* 879 * Determine if a device is in use. The 'spare_guid' parameter will be filled 880 * in with the device guid if this spare is active elsewhere on the system. 881 */ 882 static boolean_t 883 vdev_inuse(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason, 884 uint64_t *spare_guid, uint64_t *l2cache_guid) 885 { 886 spa_t *spa = vd->vdev_spa; 887 uint64_t state, pool_guid, device_guid, txg, spare_pool; 888 uint64_t vdtxg = 0; 889 nvlist_t *label; 890 891 if (spare_guid) 892 *spare_guid = 0ULL; 893 if (l2cache_guid) 894 *l2cache_guid = 0ULL; 895 896 /* 897 * Read the label, if any, and perform some basic sanity checks. 898 */ 899 if ((label = vdev_label_read_config(vd, -1ULL)) == NULL) 900 return (B_FALSE); 901 902 (void) nvlist_lookup_uint64(label, ZPOOL_CONFIG_CREATE_TXG, 903 &vdtxg); 904 905 if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_STATE, 906 &state) != 0 || 907 nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID, 908 &device_guid) != 0) { 909 nvlist_free(label); 910 return (B_FALSE); 911 } 912 913 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 914 (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID, 915 &pool_guid) != 0 || 916 nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG, 917 &txg) != 0)) { 918 nvlist_free(label); 919 return (B_FALSE); 920 } 921 922 nvlist_free(label); 923 924 /* 925 * Check to see if this device indeed belongs to the pool it claims to 926 * be a part of. The only way this is allowed is if the device is a hot 927 * spare (which we check for later on). 928 */ 929 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 930 !spa_guid_exists(pool_guid, device_guid) && 931 !spa_spare_exists(device_guid, NULL, NULL) && 932 !spa_l2cache_exists(device_guid, NULL)) 933 return (B_FALSE); 934 935 /* 936 * If the transaction group is zero, then this an initialized (but 937 * unused) label. This is only an error if the create transaction 938 * on-disk is the same as the one we're using now, in which case the 939 * user has attempted to add the same vdev multiple times in the same 940 * transaction. 941 */ 942 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 943 txg == 0 && vdtxg == crtxg) 944 return (B_TRUE); 945 946 /* 947 * Check to see if this is a spare device. We do an explicit check for 948 * spa_has_spare() here because it may be on our pending list of spares 949 * to add. 950 */ 951 if (spa_spare_exists(device_guid, &spare_pool, NULL) || 952 spa_has_spare(spa, device_guid)) { 953 if (spare_guid) 954 *spare_guid = device_guid; 955 956 switch (reason) { 957 case VDEV_LABEL_CREATE: 958 return (B_TRUE); 959 960 case VDEV_LABEL_REPLACE: 961 return (!spa_has_spare(spa, device_guid) || 962 spare_pool != 0ULL); 963 964 case VDEV_LABEL_SPARE: 965 return (spa_has_spare(spa, device_guid)); 966 default: 967 break; 968 } 969 } 970 971 /* 972 * Check to see if this is an l2cache device. 973 */ 974 if (spa_l2cache_exists(device_guid, NULL) || 975 spa_has_l2cache(spa, device_guid)) { 976 if (l2cache_guid) 977 *l2cache_guid = device_guid; 978 979 switch (reason) { 980 case VDEV_LABEL_CREATE: 981 return (B_TRUE); 982 983 case VDEV_LABEL_REPLACE: 984 return (!spa_has_l2cache(spa, device_guid)); 985 986 case VDEV_LABEL_L2CACHE: 987 return (spa_has_l2cache(spa, device_guid)); 988 default: 989 break; 990 } 991 } 992 993 /* 994 * We can't rely on a pool's state if it's been imported 995 * read-only. Instead we look to see if the pools is marked 996 * read-only in the namespace and set the state to active. 997 */ 998 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && 999 (spa = spa_by_guid(pool_guid, device_guid)) != NULL && 1000 spa_mode(spa) == SPA_MODE_READ) 1001 state = POOL_STATE_ACTIVE; 1002 1003 /* 1004 * If the device is marked ACTIVE, then this device is in use by another 1005 * pool on the system. 1006 */ 1007 return (state == POOL_STATE_ACTIVE); 1008 } 1009 1010 /* 1011 * Initialize a vdev label. We check to make sure each leaf device is not in 1012 * use, and writable. We put down an initial label which we will later 1013 * overwrite with a complete label. Note that it's important to do this 1014 * sequentially, not in parallel, so that we catch cases of multiple use of the 1015 * same leaf vdev in the vdev we're creating -- e.g. mirroring a disk with 1016 * itself. 1017 */ 1018 int 1019 vdev_label_init(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason) 1020 { 1021 spa_t *spa = vd->vdev_spa; 1022 nvlist_t *label; 1023 vdev_phys_t *vp; 1024 abd_t *vp_abd; 1025 abd_t *bootenv; 1026 uberblock_t *ub; 1027 abd_t *ub_abd; 1028 zio_t *zio; 1029 char *buf; 1030 size_t buflen; 1031 int error; 1032 uint64_t spare_guid = 0, l2cache_guid = 0; 1033 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; 1034 1035 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); 1036 1037 for (int c = 0; c < vd->vdev_children; c++) 1038 if ((error = vdev_label_init(vd->vdev_child[c], 1039 crtxg, reason)) != 0) 1040 return (error); 1041 1042 /* Track the creation time for this vdev */ 1043 vd->vdev_crtxg = crtxg; 1044 1045 if (!vd->vdev_ops->vdev_op_leaf || !spa_writeable(spa)) 1046 return (0); 1047 1048 /* 1049 * Dead vdevs cannot be initialized. 1050 */ 1051 if (vdev_is_dead(vd)) 1052 return (SET_ERROR(EIO)); 1053 1054 /* 1055 * Determine if the vdev is in use. 1056 */ 1057 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPLIT && 1058 vdev_inuse(vd, crtxg, reason, &spare_guid, &l2cache_guid)) 1059 return (SET_ERROR(EBUSY)); 1060 1061 /* 1062 * If this is a request to add or replace a spare or l2cache device 1063 * that is in use elsewhere on the system, then we must update the 1064 * guid (which was initialized to a random value) to reflect the 1065 * actual GUID (which is shared between multiple pools). 1066 */ 1067 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_L2CACHE && 1068 spare_guid != 0ULL) { 1069 uint64_t guid_delta = spare_guid - vd->vdev_guid; 1070 1071 vd->vdev_guid += guid_delta; 1072 1073 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent) 1074 pvd->vdev_guid_sum += guid_delta; 1075 1076 /* 1077 * If this is a replacement, then we want to fallthrough to the 1078 * rest of the code. If we're adding a spare, then it's already 1079 * labeled appropriately and we can just return. 1080 */ 1081 if (reason == VDEV_LABEL_SPARE) 1082 return (0); 1083 ASSERT(reason == VDEV_LABEL_REPLACE || 1084 reason == VDEV_LABEL_SPLIT); 1085 } 1086 1087 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPARE && 1088 l2cache_guid != 0ULL) { 1089 uint64_t guid_delta = l2cache_guid - vd->vdev_guid; 1090 1091 vd->vdev_guid += guid_delta; 1092 1093 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent) 1094 pvd->vdev_guid_sum += guid_delta; 1095 1096 /* 1097 * If this is a replacement, then we want to fallthrough to the 1098 * rest of the code. If we're adding an l2cache, then it's 1099 * already labeled appropriately and we can just return. 1100 */ 1101 if (reason == VDEV_LABEL_L2CACHE) 1102 return (0); 1103 ASSERT(reason == VDEV_LABEL_REPLACE); 1104 } 1105 1106 /* 1107 * Initialize its label. 1108 */ 1109 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 1110 abd_zero(vp_abd, sizeof (vdev_phys_t)); 1111 vp = abd_to_buf(vp_abd); 1112 1113 /* 1114 * Generate a label describing the pool and our top-level vdev. 1115 * We mark it as being from txg 0 to indicate that it's not 1116 * really part of an active pool just yet. The labels will 1117 * be written again with a meaningful txg by spa_sync(). 1118 */ 1119 if (reason == VDEV_LABEL_SPARE || 1120 (reason == VDEV_LABEL_REMOVE && vd->vdev_isspare)) { 1121 /* 1122 * For inactive hot spares, we generate a special label that 1123 * identifies as a mutually shared hot spare. We write the 1124 * label if we are adding a hot spare, or if we are removing an 1125 * active hot spare (in which case we want to revert the 1126 * labels). 1127 */ 1128 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1129 1130 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION, 1131 spa_version(spa)) == 0); 1132 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE, 1133 POOL_STATE_SPARE) == 0); 1134 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID, 1135 vd->vdev_guid) == 0); 1136 } else if (reason == VDEV_LABEL_L2CACHE || 1137 (reason == VDEV_LABEL_REMOVE && vd->vdev_isl2cache)) { 1138 /* 1139 * For level 2 ARC devices, add a special label. 1140 */ 1141 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0); 1142 1143 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION, 1144 spa_version(spa)) == 0); 1145 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE, 1146 POOL_STATE_L2CACHE) == 0); 1147 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID, 1148 vd->vdev_guid) == 0); 1149 1150 /* 1151 * This is merely to facilitate reporting the ashift of the 1152 * cache device through zdb. The actual retrieval of the 1153 * ashift (in vdev_alloc()) uses the nvlist 1154 * spa->spa_l2cache->sav_config (populated in 1155 * spa_ld_open_aux_vdevs()). 1156 */ 1157 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_ASHIFT, 1158 vd->vdev_ashift) == 0); 1159 } else { 1160 uint64_t txg = 0ULL; 1161 1162 if (reason == VDEV_LABEL_SPLIT) 1163 txg = spa->spa_uberblock.ub_txg; 1164 label = spa_config_generate(spa, vd, txg, B_FALSE); 1165 1166 /* 1167 * Add our creation time. This allows us to detect multiple 1168 * vdev uses as described above, and automatically expires if we 1169 * fail. 1170 */ 1171 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_CREATE_TXG, 1172 crtxg) == 0); 1173 } 1174 1175 buf = vp->vp_nvlist; 1176 buflen = sizeof (vp->vp_nvlist); 1177 1178 error = nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP); 1179 if (error != 0) { 1180 nvlist_free(label); 1181 abd_free(vp_abd); 1182 /* EFAULT means nvlist_pack ran out of room */ 1183 return (SET_ERROR(error == EFAULT ? ENAMETOOLONG : EINVAL)); 1184 } 1185 1186 /* 1187 * Initialize uberblock template. 1188 */ 1189 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_RING, B_TRUE); 1190 abd_copy_from_buf(ub_abd, &spa->spa_uberblock, sizeof (uberblock_t)); 1191 abd_zero_off(ub_abd, sizeof (uberblock_t), 1192 VDEV_UBERBLOCK_RING - sizeof (uberblock_t)); 1193 ub = abd_to_buf(ub_abd); 1194 ub->ub_txg = 0; 1195 1196 /* Initialize the 2nd padding area. */ 1197 bootenv = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE); 1198 abd_zero(bootenv, VDEV_PAD_SIZE); 1199 1200 /* 1201 * Write everything in parallel. 1202 */ 1203 retry: 1204 zio = zio_root(spa, NULL, NULL, flags); 1205 1206 for (int l = 0; l < VDEV_LABELS; l++) { 1207 1208 vdev_label_write(zio, vd, l, vp_abd, 1209 offsetof(vdev_label_t, vl_vdev_phys), 1210 sizeof (vdev_phys_t), NULL, NULL, flags); 1211 1212 /* 1213 * Skip the 1st padding area. 1214 * Zero out the 2nd padding area where it might have 1215 * left over data from previous filesystem format. 1216 */ 1217 vdev_label_write(zio, vd, l, bootenv, 1218 offsetof(vdev_label_t, vl_be), 1219 VDEV_PAD_SIZE, NULL, NULL, flags); 1220 1221 vdev_label_write(zio, vd, l, ub_abd, 1222 offsetof(vdev_label_t, vl_uberblock), 1223 VDEV_UBERBLOCK_RING, NULL, NULL, flags); 1224 } 1225 1226 error = zio_wait(zio); 1227 1228 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) { 1229 flags |= ZIO_FLAG_TRYHARD; 1230 goto retry; 1231 } 1232 1233 nvlist_free(label); 1234 abd_free(bootenv); 1235 abd_free(ub_abd); 1236 abd_free(vp_abd); 1237 1238 /* 1239 * If this vdev hasn't been previously identified as a spare, then we 1240 * mark it as such only if a) we are labeling it as a spare, or b) it 1241 * exists as a spare elsewhere in the system. Do the same for 1242 * level 2 ARC devices. 1243 */ 1244 if (error == 0 && !vd->vdev_isspare && 1245 (reason == VDEV_LABEL_SPARE || 1246 spa_spare_exists(vd->vdev_guid, NULL, NULL))) 1247 spa_spare_add(vd); 1248 1249 if (error == 0 && !vd->vdev_isl2cache && 1250 (reason == VDEV_LABEL_L2CACHE || 1251 spa_l2cache_exists(vd->vdev_guid, NULL))) 1252 spa_l2cache_add(vd); 1253 1254 return (error); 1255 } 1256 1257 /* 1258 * Done callback for vdev_label_read_bootenv_impl. If this is the first 1259 * callback to finish, store our abd in the callback pointer. Otherwise, we 1260 * just free our abd and return. 1261 */ 1262 static void 1263 vdev_label_read_bootenv_done(zio_t *zio) 1264 { 1265 zio_t *rio = zio->io_private; 1266 abd_t **cbp = rio->io_private; 1267 1268 ASSERT3U(zio->io_size, ==, VDEV_PAD_SIZE); 1269 1270 if (zio->io_error == 0) { 1271 mutex_enter(&rio->io_lock); 1272 if (*cbp == NULL) { 1273 /* Will free this buffer in vdev_label_read_bootenv. */ 1274 *cbp = zio->io_abd; 1275 } else { 1276 abd_free(zio->io_abd); 1277 } 1278 mutex_exit(&rio->io_lock); 1279 } else { 1280 abd_free(zio->io_abd); 1281 } 1282 } 1283 1284 static void 1285 vdev_label_read_bootenv_impl(zio_t *zio, vdev_t *vd, int flags) 1286 { 1287 for (int c = 0; c < vd->vdev_children; c++) 1288 vdev_label_read_bootenv_impl(zio, vd->vdev_child[c], flags); 1289 1290 /* 1291 * We just use the first label that has a correct checksum; the 1292 * bootloader should have rewritten them all to be the same on boot, 1293 * and any changes we made since boot have been the same across all 1294 * labels. 1295 */ 1296 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd)) { 1297 for (int l = 0; l < VDEV_LABELS; l++) { 1298 vdev_label_read(zio, vd, l, 1299 abd_alloc_linear(VDEV_PAD_SIZE, B_FALSE), 1300 offsetof(vdev_label_t, vl_be), VDEV_PAD_SIZE, 1301 vdev_label_read_bootenv_done, zio, flags); 1302 } 1303 } 1304 } 1305 1306 int 1307 vdev_label_read_bootenv(vdev_t *rvd, nvlist_t *bootenv) 1308 { 1309 nvlist_t *config; 1310 spa_t *spa = rvd->vdev_spa; 1311 abd_t *abd = NULL; 1312 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 1313 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD; 1314 1315 ASSERT(bootenv); 1316 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); 1317 1318 zio_t *zio = zio_root(spa, NULL, &abd, flags); 1319 vdev_label_read_bootenv_impl(zio, rvd, flags); 1320 int err = zio_wait(zio); 1321 1322 if (abd != NULL) { 1323 char *buf; 1324 vdev_boot_envblock_t *vbe = abd_to_buf(abd); 1325 1326 vbe->vbe_version = ntohll(vbe->vbe_version); 1327 switch (vbe->vbe_version) { 1328 case VB_RAW: 1329 /* 1330 * if we have textual data in vbe_bootenv, create nvlist 1331 * with key "envmap". 1332 */ 1333 fnvlist_add_uint64(bootenv, BOOTENV_VERSION, VB_RAW); 1334 vbe->vbe_bootenv[sizeof (vbe->vbe_bootenv) - 1] = '\0'; 1335 fnvlist_add_string(bootenv, GRUB_ENVMAP, 1336 vbe->vbe_bootenv); 1337 break; 1338 1339 case VB_NVLIST: 1340 err = nvlist_unpack(vbe->vbe_bootenv, 1341 sizeof (vbe->vbe_bootenv), &config, 0); 1342 if (err == 0) { 1343 fnvlist_merge(bootenv, config); 1344 nvlist_free(config); 1345 break; 1346 } 1347 zfs_fallthrough; 1348 default: 1349 /* Check for FreeBSD zfs bootonce command string */ 1350 buf = abd_to_buf(abd); 1351 if (*buf == '\0') { 1352 fnvlist_add_uint64(bootenv, BOOTENV_VERSION, 1353 VB_NVLIST); 1354 break; 1355 } 1356 fnvlist_add_string(bootenv, FREEBSD_BOOTONCE, buf); 1357 } 1358 1359 /* 1360 * abd was allocated in vdev_label_read_bootenv_impl() 1361 */ 1362 abd_free(abd); 1363 /* 1364 * If we managed to read any successfully, 1365 * return success. 1366 */ 1367 return (0); 1368 } 1369 return (err); 1370 } 1371 1372 int 1373 vdev_label_write_bootenv(vdev_t *vd, nvlist_t *env) 1374 { 1375 zio_t *zio; 1376 spa_t *spa = vd->vdev_spa; 1377 vdev_boot_envblock_t *bootenv; 1378 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; 1379 int error; 1380 size_t nvsize; 1381 char *nvbuf; 1382 const char *tmp; 1383 1384 error = nvlist_size(env, &nvsize, NV_ENCODE_XDR); 1385 if (error != 0) 1386 return (SET_ERROR(error)); 1387 1388 if (nvsize >= sizeof (bootenv->vbe_bootenv)) { 1389 return (SET_ERROR(E2BIG)); 1390 } 1391 1392 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL); 1393 1394 error = ENXIO; 1395 for (int c = 0; c < vd->vdev_children; c++) { 1396 int child_err; 1397 1398 child_err = vdev_label_write_bootenv(vd->vdev_child[c], env); 1399 /* 1400 * As long as any of the disks managed to write all of their 1401 * labels successfully, return success. 1402 */ 1403 if (child_err == 0) 1404 error = child_err; 1405 } 1406 1407 if (!vd->vdev_ops->vdev_op_leaf || vdev_is_dead(vd) || 1408 !vdev_writeable(vd)) { 1409 return (error); 1410 } 1411 ASSERT3U(sizeof (*bootenv), ==, VDEV_PAD_SIZE); 1412 abd_t *abd = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE); 1413 abd_zero(abd, VDEV_PAD_SIZE); 1414 1415 bootenv = abd_borrow_buf_copy(abd, VDEV_PAD_SIZE); 1416 nvbuf = bootenv->vbe_bootenv; 1417 nvsize = sizeof (bootenv->vbe_bootenv); 1418 1419 bootenv->vbe_version = fnvlist_lookup_uint64(env, BOOTENV_VERSION); 1420 switch (bootenv->vbe_version) { 1421 case VB_RAW: 1422 if (nvlist_lookup_string(env, GRUB_ENVMAP, &tmp) == 0) { 1423 (void) strlcpy(bootenv->vbe_bootenv, tmp, nvsize); 1424 } 1425 error = 0; 1426 break; 1427 1428 case VB_NVLIST: 1429 error = nvlist_pack(env, &nvbuf, &nvsize, NV_ENCODE_XDR, 1430 KM_SLEEP); 1431 break; 1432 1433 default: 1434 error = EINVAL; 1435 break; 1436 } 1437 1438 if (error == 0) { 1439 bootenv->vbe_version = htonll(bootenv->vbe_version); 1440 abd_return_buf_copy(abd, bootenv, VDEV_PAD_SIZE); 1441 } else { 1442 abd_free(abd); 1443 return (SET_ERROR(error)); 1444 } 1445 1446 retry: 1447 zio = zio_root(spa, NULL, NULL, flags); 1448 for (int l = 0; l < VDEV_LABELS; l++) { 1449 vdev_label_write(zio, vd, l, abd, 1450 offsetof(vdev_label_t, vl_be), 1451 VDEV_PAD_SIZE, NULL, NULL, flags); 1452 } 1453 1454 error = zio_wait(zio); 1455 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) { 1456 flags |= ZIO_FLAG_TRYHARD; 1457 goto retry; 1458 } 1459 1460 abd_free(abd); 1461 return (error); 1462 } 1463 1464 /* 1465 * ========================================================================== 1466 * uberblock load/sync 1467 * ========================================================================== 1468 */ 1469 1470 /* 1471 * Consider the following situation: txg is safely synced to disk. We've 1472 * written the first uberblock for txg + 1, and then we lose power. When we 1473 * come back up, we fail to see the uberblock for txg + 1 because, say, 1474 * it was on a mirrored device and the replica to which we wrote txg + 1 1475 * is now offline. If we then make some changes and sync txg + 1, and then 1476 * the missing replica comes back, then for a few seconds we'll have two 1477 * conflicting uberblocks on disk with the same txg. The solution is simple: 1478 * among uberblocks with equal txg, choose the one with the latest timestamp. 1479 */ 1480 static int 1481 vdev_uberblock_compare(const uberblock_t *ub1, const uberblock_t *ub2) 1482 { 1483 int cmp = TREE_CMP(ub1->ub_txg, ub2->ub_txg); 1484 1485 if (likely(cmp)) 1486 return (cmp); 1487 1488 cmp = TREE_CMP(ub1->ub_timestamp, ub2->ub_timestamp); 1489 if (likely(cmp)) 1490 return (cmp); 1491 1492 /* 1493 * If MMP_VALID(ub) && MMP_SEQ_VALID(ub) then the host has an MMP-aware 1494 * ZFS, e.g. OpenZFS >= 0.7. 1495 * 1496 * If one ub has MMP and the other does not, they were written by 1497 * different hosts, which matters for MMP. So we treat no MMP/no SEQ as 1498 * a 0 value. 1499 * 1500 * Since timestamp and txg are the same if we get this far, either is 1501 * acceptable for importing the pool. 1502 */ 1503 unsigned int seq1 = 0; 1504 unsigned int seq2 = 0; 1505 1506 if (MMP_VALID(ub1) && MMP_SEQ_VALID(ub1)) 1507 seq1 = MMP_SEQ(ub1); 1508 1509 if (MMP_VALID(ub2) && MMP_SEQ_VALID(ub2)) 1510 seq2 = MMP_SEQ(ub2); 1511 1512 return (TREE_CMP(seq1, seq2)); 1513 } 1514 1515 struct ubl_cbdata { 1516 uberblock_t ubl_latest; /* Most recent uberblock */ 1517 uberblock_t *ubl_ubbest; /* Best uberblock (w/r/t max_txg) */ 1518 vdev_t *ubl_vd; /* vdev associated with the above */ 1519 }; 1520 1521 static void 1522 vdev_uberblock_load_done(zio_t *zio) 1523 { 1524 vdev_t *vd = zio->io_vd; 1525 spa_t *spa = zio->io_spa; 1526 zio_t *rio = zio->io_private; 1527 uberblock_t *ub = abd_to_buf(zio->io_abd); 1528 struct ubl_cbdata *cbp = rio->io_private; 1529 1530 ASSERT3U(zio->io_size, ==, VDEV_UBERBLOCK_SIZE(vd)); 1531 1532 if (zio->io_error == 0 && uberblock_verify(ub) == 0) { 1533 mutex_enter(&rio->io_lock); 1534 if (vdev_uberblock_compare(ub, &cbp->ubl_latest) > 0) { 1535 cbp->ubl_latest = *ub; 1536 } 1537 if (ub->ub_txg <= spa->spa_load_max_txg && 1538 vdev_uberblock_compare(ub, cbp->ubl_ubbest) > 0) { 1539 /* 1540 * Keep track of the vdev in which this uberblock 1541 * was found. We will use this information later 1542 * to obtain the config nvlist associated with 1543 * this uberblock. 1544 */ 1545 *cbp->ubl_ubbest = *ub; 1546 cbp->ubl_vd = vd; 1547 } 1548 mutex_exit(&rio->io_lock); 1549 } 1550 1551 abd_free(zio->io_abd); 1552 } 1553 1554 static void 1555 vdev_uberblock_load_impl(zio_t *zio, vdev_t *vd, int flags, 1556 struct ubl_cbdata *cbp) 1557 { 1558 for (int c = 0; c < vd->vdev_children; c++) 1559 vdev_uberblock_load_impl(zio, vd->vdev_child[c], flags, cbp); 1560 1561 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd) && 1562 vd->vdev_ops != &vdev_draid_spare_ops) { 1563 for (int l = 0; l < VDEV_LABELS; l++) { 1564 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) { 1565 vdev_label_read(zio, vd, l, 1566 abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), 1567 B_TRUE), VDEV_UBERBLOCK_OFFSET(vd, n), 1568 VDEV_UBERBLOCK_SIZE(vd), 1569 vdev_uberblock_load_done, zio, flags); 1570 } 1571 } 1572 } 1573 } 1574 1575 /* 1576 * Reads the 'best' uberblock from disk along with its associated 1577 * configuration. First, we read the uberblock array of each label of each 1578 * vdev, keeping track of the uberblock with the highest txg in each array. 1579 * Then, we read the configuration from the same vdev as the best uberblock. 1580 */ 1581 void 1582 vdev_uberblock_load(vdev_t *rvd, uberblock_t *ub, nvlist_t **config) 1583 { 1584 zio_t *zio; 1585 spa_t *spa = rvd->vdev_spa; 1586 struct ubl_cbdata cb; 1587 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 1588 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD; 1589 1590 ASSERT(ub); 1591 ASSERT(config); 1592 1593 memset(ub, 0, sizeof (uberblock_t)); 1594 memset(&cb, 0, sizeof (cb)); 1595 *config = NULL; 1596 1597 cb.ubl_ubbest = ub; 1598 1599 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 1600 zio = zio_root(spa, NULL, &cb, flags); 1601 vdev_uberblock_load_impl(zio, rvd, flags, &cb); 1602 (void) zio_wait(zio); 1603 1604 /* 1605 * It's possible that the best uberblock was discovered on a label 1606 * that has a configuration which was written in a future txg. 1607 * Search all labels on this vdev to find the configuration that 1608 * matches the txg for our uberblock. 1609 */ 1610 if (cb.ubl_vd != NULL) { 1611 vdev_dbgmsg(cb.ubl_vd, "best uberblock found for spa %s. " 1612 "txg %llu", spa->spa_name, (u_longlong_t)ub->ub_txg); 1613 1614 if (ub->ub_raidz_reflow_info != 1615 cb.ubl_latest.ub_raidz_reflow_info) { 1616 vdev_dbgmsg(cb.ubl_vd, 1617 "spa=%s best uberblock (txg=%llu info=0x%llx) " 1618 "has different raidz_reflow_info than latest " 1619 "uberblock (txg=%llu info=0x%llx)", 1620 spa->spa_name, 1621 (u_longlong_t)ub->ub_txg, 1622 (u_longlong_t)ub->ub_raidz_reflow_info, 1623 (u_longlong_t)cb.ubl_latest.ub_txg, 1624 (u_longlong_t)cb.ubl_latest.ub_raidz_reflow_info); 1625 memset(ub, 0, sizeof (uberblock_t)); 1626 spa_config_exit(spa, SCL_ALL, FTAG); 1627 return; 1628 } 1629 1630 *config = vdev_label_read_config(cb.ubl_vd, ub->ub_txg); 1631 if (*config == NULL && spa->spa_extreme_rewind) { 1632 vdev_dbgmsg(cb.ubl_vd, "failed to read label config. " 1633 "Trying again without txg restrictions."); 1634 *config = vdev_label_read_config(cb.ubl_vd, UINT64_MAX); 1635 } 1636 if (*config == NULL) { 1637 vdev_dbgmsg(cb.ubl_vd, "failed to read label config"); 1638 } 1639 } 1640 spa_config_exit(spa, SCL_ALL, FTAG); 1641 } 1642 1643 /* 1644 * For use when a leaf vdev is expanded. 1645 * The location of labels 2 and 3 changed, and at the new location the 1646 * uberblock rings are either empty or contain garbage. The sync will write 1647 * new configs there because the vdev is dirty, but expansion also needs the 1648 * uberblock rings copied. Read them from label 0 which did not move. 1649 * 1650 * Since the point is to populate labels {2,3} with valid uberblocks, 1651 * we zero uberblocks we fail to read or which are not valid. 1652 */ 1653 1654 static void 1655 vdev_copy_uberblocks(vdev_t *vd) 1656 { 1657 abd_t *ub_abd; 1658 zio_t *write_zio; 1659 int locks = (SCL_L2ARC | SCL_ZIO); 1660 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL | 1661 ZIO_FLAG_SPECULATIVE; 1662 1663 ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_READER) == 1664 SCL_STATE); 1665 ASSERT(vd->vdev_ops->vdev_op_leaf); 1666 1667 /* 1668 * No uberblocks are stored on distributed spares, they may be 1669 * safely skipped when expanding a leaf vdev. 1670 */ 1671 if (vd->vdev_ops == &vdev_draid_spare_ops) 1672 return; 1673 1674 spa_config_enter(vd->vdev_spa, locks, FTAG, RW_READER); 1675 1676 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), B_TRUE); 1677 1678 write_zio = zio_root(vd->vdev_spa, NULL, NULL, flags); 1679 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) { 1680 const int src_label = 0; 1681 zio_t *zio; 1682 1683 zio = zio_root(vd->vdev_spa, NULL, NULL, flags); 1684 vdev_label_read(zio, vd, src_label, ub_abd, 1685 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd), 1686 NULL, NULL, flags); 1687 1688 if (zio_wait(zio) || uberblock_verify(abd_to_buf(ub_abd))) 1689 abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd)); 1690 1691 for (int l = 2; l < VDEV_LABELS; l++) 1692 vdev_label_write(write_zio, vd, l, ub_abd, 1693 VDEV_UBERBLOCK_OFFSET(vd, n), 1694 VDEV_UBERBLOCK_SIZE(vd), NULL, NULL, 1695 flags | ZIO_FLAG_DONT_PROPAGATE); 1696 } 1697 (void) zio_wait(write_zio); 1698 1699 spa_config_exit(vd->vdev_spa, locks, FTAG); 1700 1701 abd_free(ub_abd); 1702 } 1703 1704 /* 1705 * On success, increment root zio's count of good writes. 1706 * We only get credit for writes to known-visible vdevs; see spa_vdev_add(). 1707 */ 1708 static void 1709 vdev_uberblock_sync_done(zio_t *zio) 1710 { 1711 uint64_t *good_writes = zio->io_private; 1712 1713 if (zio->io_error == 0 && zio->io_vd->vdev_top->vdev_ms_array != 0) 1714 atomic_inc_64(good_writes); 1715 } 1716 1717 /* 1718 * Write the uberblock to all labels of all leaves of the specified vdev. 1719 */ 1720 static void 1721 vdev_uberblock_sync(zio_t *zio, uint64_t *good_writes, 1722 uberblock_t *ub, vdev_t *vd, int flags) 1723 { 1724 for (uint64_t c = 0; c < vd->vdev_children; c++) { 1725 vdev_uberblock_sync(zio, good_writes, 1726 ub, vd->vdev_child[c], flags); 1727 } 1728 1729 if (!vd->vdev_ops->vdev_op_leaf) 1730 return; 1731 1732 if (!vdev_writeable(vd)) 1733 return; 1734 1735 /* 1736 * There's no need to write uberblocks to a distributed spare, they 1737 * are already stored on all the leaves of the parent dRAID. For 1738 * this same reason vdev_uberblock_load_impl() skips distributed 1739 * spares when reading uberblocks. 1740 */ 1741 if (vd->vdev_ops == &vdev_draid_spare_ops) 1742 return; 1743 1744 /* If the vdev was expanded, need to copy uberblock rings. */ 1745 if (vd->vdev_state == VDEV_STATE_HEALTHY && 1746 vd->vdev_copy_uberblocks == B_TRUE) { 1747 vdev_copy_uberblocks(vd); 1748 vd->vdev_copy_uberblocks = B_FALSE; 1749 } 1750 1751 /* 1752 * We chose a slot based on the txg. If this uberblock has a special 1753 * RAIDZ expansion state, then it is essentially an update of the 1754 * current uberblock (it has the same txg). However, the current 1755 * state is committed, so we want to write it to a different slot. If 1756 * we overwrote the same slot, and we lose power during the uberblock 1757 * write, and the disk does not do single-sector overwrites 1758 * atomically (even though it is required to - i.e. we should see 1759 * either the old or the new uberblock), then we could lose this 1760 * txg's uberblock. Rewinding to the previous txg's uberblock may not 1761 * be possible because RAIDZ expansion may have already overwritten 1762 * some of the data, so we need the progress indicator in the 1763 * uberblock. 1764 */ 1765 int m = spa_multihost(vd->vdev_spa) ? MMP_BLOCKS_PER_LABEL : 0; 1766 int n = (ub->ub_txg - (RRSS_GET_STATE(ub) == RRSS_SCRATCH_VALID)) % 1767 (VDEV_UBERBLOCK_COUNT(vd) - m); 1768 1769 /* Copy the uberblock_t into the ABD */ 1770 abd_t *ub_abd = abd_alloc_for_io(VDEV_UBERBLOCK_SIZE(vd), B_TRUE); 1771 abd_copy_from_buf(ub_abd, ub, sizeof (uberblock_t)); 1772 abd_zero_off(ub_abd, sizeof (uberblock_t), 1773 VDEV_UBERBLOCK_SIZE(vd) - sizeof (uberblock_t)); 1774 1775 for (int l = 0; l < VDEV_LABELS; l++) 1776 vdev_label_write(zio, vd, l, ub_abd, 1777 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd), 1778 vdev_uberblock_sync_done, good_writes, 1779 flags | ZIO_FLAG_DONT_PROPAGATE); 1780 1781 abd_free(ub_abd); 1782 } 1783 1784 /* Sync the uberblocks to all vdevs in svd[] */ 1785 int 1786 vdev_uberblock_sync_list(vdev_t **svd, int svdcount, uberblock_t *ub, int flags) 1787 { 1788 spa_t *spa = svd[0]->vdev_spa; 1789 zio_t *zio; 1790 uint64_t good_writes = 0; 1791 1792 zio = zio_root(spa, NULL, NULL, flags); 1793 1794 for (int v = 0; v < svdcount; v++) 1795 vdev_uberblock_sync(zio, &good_writes, ub, svd[v], flags); 1796 1797 (void) zio_wait(zio); 1798 1799 /* 1800 * Flush the uberblocks to disk. This ensures that the odd labels 1801 * are no longer needed (because the new uberblocks and the even 1802 * labels are safely on disk), so it is safe to overwrite them. 1803 */ 1804 zio = zio_root(spa, NULL, NULL, flags); 1805 1806 for (int v = 0; v < svdcount; v++) { 1807 if (vdev_writeable(svd[v])) { 1808 zio_flush(zio, svd[v]); 1809 } 1810 } 1811 1812 (void) zio_wait(zio); 1813 1814 return (good_writes >= 1 ? 0 : EIO); 1815 } 1816 1817 /* 1818 * On success, increment the count of good writes for our top-level vdev. 1819 */ 1820 static void 1821 vdev_label_sync_done(zio_t *zio) 1822 { 1823 uint64_t *good_writes = zio->io_private; 1824 1825 if (zio->io_error == 0) 1826 atomic_inc_64(good_writes); 1827 } 1828 1829 /* 1830 * If there weren't enough good writes, indicate failure to the parent. 1831 */ 1832 static void 1833 vdev_label_sync_top_done(zio_t *zio) 1834 { 1835 uint64_t *good_writes = zio->io_private; 1836 1837 if (*good_writes == 0) 1838 zio->io_error = SET_ERROR(EIO); 1839 1840 kmem_free(good_writes, sizeof (uint64_t)); 1841 } 1842 1843 /* 1844 * We ignore errors for log and cache devices, simply free the private data. 1845 */ 1846 static void 1847 vdev_label_sync_ignore_done(zio_t *zio) 1848 { 1849 kmem_free(zio->io_private, sizeof (uint64_t)); 1850 } 1851 1852 /* 1853 * Write all even or odd labels to all leaves of the specified vdev. 1854 */ 1855 static void 1856 vdev_label_sync(zio_t *zio, uint64_t *good_writes, 1857 vdev_t *vd, int l, uint64_t txg, int flags) 1858 { 1859 nvlist_t *label; 1860 vdev_phys_t *vp; 1861 abd_t *vp_abd; 1862 char *buf; 1863 size_t buflen; 1864 1865 for (int c = 0; c < vd->vdev_children; c++) { 1866 vdev_label_sync(zio, good_writes, 1867 vd->vdev_child[c], l, txg, flags); 1868 } 1869 1870 if (!vd->vdev_ops->vdev_op_leaf) 1871 return; 1872 1873 if (!vdev_writeable(vd)) 1874 return; 1875 1876 /* 1877 * The top-level config never needs to be written to a distributed 1878 * spare. When read vdev_dspare_label_read_config() will generate 1879 * the config for the vdev_label_read_config(). 1880 */ 1881 if (vd->vdev_ops == &vdev_draid_spare_ops) 1882 return; 1883 1884 /* 1885 * Generate a label describing the top-level config to which we belong. 1886 */ 1887 label = spa_config_generate(vd->vdev_spa, vd, txg, B_FALSE); 1888 1889 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE); 1890 abd_zero(vp_abd, sizeof (vdev_phys_t)); 1891 vp = abd_to_buf(vp_abd); 1892 1893 buf = vp->vp_nvlist; 1894 buflen = sizeof (vp->vp_nvlist); 1895 1896 if (!nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP)) { 1897 for (; l < VDEV_LABELS; l += 2) { 1898 vdev_label_write(zio, vd, l, vp_abd, 1899 offsetof(vdev_label_t, vl_vdev_phys), 1900 sizeof (vdev_phys_t), 1901 vdev_label_sync_done, good_writes, 1902 flags | ZIO_FLAG_DONT_PROPAGATE); 1903 } 1904 } 1905 1906 abd_free(vp_abd); 1907 nvlist_free(label); 1908 } 1909 1910 static int 1911 vdev_label_sync_list(spa_t *spa, int l, uint64_t txg, int flags) 1912 { 1913 list_t *dl = &spa->spa_config_dirty_list; 1914 vdev_t *vd; 1915 zio_t *zio; 1916 int error; 1917 1918 /* 1919 * Write the new labels to disk. 1920 */ 1921 zio = zio_root(spa, NULL, NULL, flags); 1922 1923 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) { 1924 uint64_t *good_writes; 1925 1926 ASSERT(!vd->vdev_ishole); 1927 1928 good_writes = kmem_zalloc(sizeof (uint64_t), KM_SLEEP); 1929 zio_t *vio = zio_null(zio, spa, NULL, 1930 (vd->vdev_islog || vd->vdev_aux != NULL) ? 1931 vdev_label_sync_ignore_done : vdev_label_sync_top_done, 1932 good_writes, flags); 1933 vdev_label_sync(vio, good_writes, vd, l, txg, flags); 1934 zio_nowait(vio); 1935 } 1936 1937 error = zio_wait(zio); 1938 1939 /* 1940 * Flush the new labels to disk. 1941 */ 1942 zio = zio_root(spa, NULL, NULL, flags); 1943 1944 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) 1945 zio_flush(zio, vd); 1946 1947 (void) zio_wait(zio); 1948 1949 return (error); 1950 } 1951 1952 /* 1953 * Sync the uberblock and any changes to the vdev configuration. 1954 * 1955 * The order of operations is carefully crafted to ensure that 1956 * if the system panics or loses power at any time, the state on disk 1957 * is still transactionally consistent. The in-line comments below 1958 * describe the failure semantics at each stage. 1959 * 1960 * Moreover, vdev_config_sync() is designed to be idempotent: if it fails 1961 * at any time, you can just call it again, and it will resume its work. 1962 */ 1963 int 1964 vdev_config_sync(vdev_t **svd, int svdcount, uint64_t txg) 1965 { 1966 spa_t *spa = svd[0]->vdev_spa; 1967 uberblock_t *ub = &spa->spa_uberblock; 1968 int error = 0; 1969 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL; 1970 1971 ASSERT(svdcount != 0); 1972 retry: 1973 /* 1974 * Normally, we don't want to try too hard to write every label and 1975 * uberblock. If there is a flaky disk, we don't want the rest of the 1976 * sync process to block while we retry. But if we can't write a 1977 * single label out, we should retry with ZIO_FLAG_TRYHARD before 1978 * bailing out and declaring the pool faulted. 1979 */ 1980 if (error != 0) { 1981 if ((flags & ZIO_FLAG_TRYHARD) != 0) 1982 return (error); 1983 flags |= ZIO_FLAG_TRYHARD; 1984 } 1985 1986 ASSERT(ub->ub_txg <= txg); 1987 1988 /* 1989 * If this isn't a resync due to I/O errors, 1990 * and nothing changed in this transaction group, 1991 * and the vdev configuration hasn't changed, 1992 * then there's nothing to do. 1993 */ 1994 if (ub->ub_txg < txg) { 1995 boolean_t changed = uberblock_update(ub, spa->spa_root_vdev, 1996 txg, spa->spa_mmp.mmp_delay); 1997 1998 if (!changed && list_is_empty(&spa->spa_config_dirty_list)) 1999 return (0); 2000 } 2001 2002 if (txg > spa_freeze_txg(spa)) 2003 return (0); 2004 2005 ASSERT(txg <= spa->spa_final_txg); 2006 2007 /* 2008 * Flush the write cache of every disk that's been written to 2009 * in this transaction group. This ensures that all blocks 2010 * written in this txg will be committed to stable storage 2011 * before any uberblock that references them. 2012 */ 2013 zio_t *zio = zio_root(spa, NULL, NULL, flags); 2014 2015 for (vdev_t *vd = 2016 txg_list_head(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)); vd != NULL; 2017 vd = txg_list_next(&spa->spa_vdev_txg_list, vd, TXG_CLEAN(txg))) 2018 zio_flush(zio, vd); 2019 2020 (void) zio_wait(zio); 2021 2022 /* 2023 * Sync out the even labels (L0, L2) for every dirty vdev. If the 2024 * system dies in the middle of this process, that's OK: all of the 2025 * even labels that made it to disk will be newer than any uberblock, 2026 * and will therefore be considered invalid. The odd labels (L1, L3), 2027 * which have not yet been touched, will still be valid. We flush 2028 * the new labels to disk to ensure that all even-label updates 2029 * are committed to stable storage before the uberblock update. 2030 */ 2031 if ((error = vdev_label_sync_list(spa, 0, txg, flags)) != 0) { 2032 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 2033 zfs_dbgmsg("vdev_label_sync_list() returned error %d " 2034 "for pool '%s' when syncing out the even labels " 2035 "of dirty vdevs", error, spa_name(spa)); 2036 } 2037 goto retry; 2038 } 2039 2040 /* 2041 * Sync the uberblocks to all vdevs in svd[]. 2042 * If the system dies in the middle of this step, there are two cases 2043 * to consider, and the on-disk state is consistent either way: 2044 * 2045 * (1) If none of the new uberblocks made it to disk, then the 2046 * previous uberblock will be the newest, and the odd labels 2047 * (which had not yet been touched) will be valid with respect 2048 * to that uberblock. 2049 * 2050 * (2) If one or more new uberblocks made it to disk, then they 2051 * will be the newest, and the even labels (which had all 2052 * been successfully committed) will be valid with respect 2053 * to the new uberblocks. 2054 */ 2055 if ((error = vdev_uberblock_sync_list(svd, svdcount, ub, flags)) != 0) { 2056 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 2057 zfs_dbgmsg("vdev_uberblock_sync_list() returned error " 2058 "%d for pool '%s'", error, spa_name(spa)); 2059 } 2060 goto retry; 2061 } 2062 2063 if (spa_multihost(spa)) 2064 mmp_update_uberblock(spa, ub); 2065 2066 /* 2067 * Sync out odd labels for every dirty vdev. If the system dies 2068 * in the middle of this process, the even labels and the new 2069 * uberblocks will suffice to open the pool. The next time 2070 * the pool is opened, the first thing we'll do -- before any 2071 * user data is modified -- is mark every vdev dirty so that 2072 * all labels will be brought up to date. We flush the new labels 2073 * to disk to ensure that all odd-label updates are committed to 2074 * stable storage before the next transaction group begins. 2075 */ 2076 if ((error = vdev_label_sync_list(spa, 1, txg, flags)) != 0) { 2077 if ((flags & ZIO_FLAG_TRYHARD) != 0) { 2078 zfs_dbgmsg("vdev_label_sync_list() returned error %d " 2079 "for pool '%s' when syncing out the odd labels of " 2080 "dirty vdevs", error, spa_name(spa)); 2081 } 2082 goto retry; 2083 } 2084 2085 return (0); 2086 } 2087