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) 2011, 2014 by Delphix. All rights reserved.
  25  * Copyright (c) 2013, 2014, Nexenta Systems, Inc.  All rights reserved.
  26  */
  27 
  28 /*
  29  * SPA: Storage Pool Allocator
  30  *
  31  * This file contains all the routines used when modifying on-disk SPA state.
  32  * This includes opening, importing, destroying, exporting a pool, and syncing a
  33  * pool.
  34  */
  35 
  36 #include <sys/zfs_context.h>
  37 #include <sys/fm/fs/zfs.h>
  38 #include <sys/spa_impl.h>
  39 #include <sys/zio.h>
  40 #include <sys/zio_checksum.h>
  41 #include <sys/dmu.h>
  42 #include <sys/dmu_tx.h>
  43 #include <sys/zap.h>
  44 #include <sys/zil.h>
  45 #include <sys/ddt.h>
  46 #include <sys/vdev_impl.h>
  47 #include <sys/metaslab.h>
  48 #include <sys/metaslab_impl.h>
  49 #include <sys/uberblock_impl.h>
  50 #include <sys/txg.h>
  51 #include <sys/avl.h>
  52 #include <sys/dmu_traverse.h>
  53 #include <sys/dmu_objset.h>
  54 #include <sys/unique.h>
  55 #include <sys/dsl_pool.h>
  56 #include <sys/dsl_dataset.h>
  57 #include <sys/dsl_dir.h>
  58 #include <sys/dsl_prop.h>
  59 #include <sys/dsl_synctask.h>
  60 #include <sys/fs/zfs.h>
  61 #include <sys/arc.h>
  62 #include <sys/callb.h>
  63 #include <sys/systeminfo.h>
  64 #include <sys/spa_boot.h>
  65 #include <sys/zfs_ioctl.h>
  66 #include <sys/dsl_scan.h>
  67 #include <sys/zfeature.h>
  68 #include <sys/dsl_destroy.h>
  69 
  70 #ifdef  _KERNEL
  71 #include <sys/bootprops.h>
  72 #include <sys/callb.h>
  73 #include <sys/cpupart.h>
  74 #include <sys/pool.h>
  75 #include <sys/sysdc.h>
  76 #include <sys/zone.h>
  77 #endif  /* _KERNEL */
  78 
  79 #include "zfs_prop.h"
  80 #include "zfs_comutil.h"
  81 
  82 /*
  83  * The interval, in seconds, at which failed configuration cache file writes
  84  * should be retried.
  85  */
  86 static int zfs_ccw_retry_interval = 300;
  87 
  88 typedef enum zti_modes {
  89         ZTI_MODE_FIXED,                 /* value is # of threads (min 1) */
  90         ZTI_MODE_BATCH,                 /* cpu-intensive; value is ignored */
  91         ZTI_MODE_NULL,                  /* don't create a taskq */
  92         ZTI_NMODES
  93 } zti_modes_t;
  94 
  95 #define ZTI_P(n, q)     { ZTI_MODE_FIXED, (n), (q) }
  96 #define ZTI_BATCH       { ZTI_MODE_BATCH, 0, 1 }
  97 #define ZTI_NULL        { ZTI_MODE_NULL, 0, 0 }
  98 
  99 #define ZTI_N(n)        ZTI_P(n, 1)
 100 #define ZTI_ONE         ZTI_N(1)
 101 
 102 typedef struct zio_taskq_info {
 103         zti_modes_t zti_mode;
 104         uint_t zti_value;
 105         uint_t zti_count;
 106 } zio_taskq_info_t;
 107 
 108 static const char *const zio_taskq_types[ZIO_TASKQ_TYPES] = {
 109         "issue", "issue_high", "intr", "intr_high"
 110 };
 111 
 112 /*
 113  * This table defines the taskq settings for each ZFS I/O type. When
 114  * initializing a pool, we use this table to create an appropriately sized
 115  * taskq. Some operations are low volume and therefore have a small, static
 116  * number of threads assigned to their taskqs using the ZTI_N(#) or ZTI_ONE
 117  * macros. Other operations process a large amount of data; the ZTI_BATCH
 118  * macro causes us to create a taskq oriented for throughput. Some operations
 119  * are so high frequency and short-lived that the taskq itself can become a a
 120  * point of lock contention. The ZTI_P(#, #) macro indicates that we need an
 121  * additional degree of parallelism specified by the number of threads per-
 122  * taskq and the number of taskqs; when dispatching an event in this case, the
 123  * particular taskq is chosen at random.
 124  *
 125  * The different taskq priorities are to handle the different contexts (issue
 126  * and interrupt) and then to reserve threads for ZIO_PRIORITY_NOW I/Os that
 127  * need to be handled with minimum delay.
 128  */
 129 const zio_taskq_info_t zio_taskqs[ZIO_TYPES][ZIO_TASKQ_TYPES] = {
 130         /* ISSUE        ISSUE_HIGH      INTR            INTR_HIGH */
 131         { ZTI_ONE,      ZTI_NULL,       ZTI_ONE,        ZTI_NULL }, /* NULL */
 132         { ZTI_N(8),     ZTI_NULL,       ZTI_P(12, 8),   ZTI_NULL }, /* READ */
 133         { ZTI_BATCH,    ZTI_N(5),       ZTI_N(8),       ZTI_N(5) }, /* WRITE */
 134         { ZTI_P(12, 8), ZTI_NULL,       ZTI_ONE,        ZTI_NULL }, /* FREE */
 135         { ZTI_ONE,      ZTI_NULL,       ZTI_ONE,        ZTI_NULL }, /* CLAIM */
 136         { ZTI_ONE,      ZTI_NULL,       ZTI_ONE,        ZTI_NULL }, /* IOCTL */
 137 };
 138 
 139 static void spa_sync_version(void *arg, dmu_tx_t *tx);
 140 static void spa_sync_props(void *arg, dmu_tx_t *tx);
 141 static boolean_t spa_has_active_shared_spare(spa_t *spa);
 142 static int spa_load_impl(spa_t *spa, uint64_t, nvlist_t *config,
 143     spa_load_state_t state, spa_import_type_t type, boolean_t mosconfig,
 144     char **ereport);
 145 static void spa_vdev_resilver_done(spa_t *spa);
 146 
 147 uint_t          zio_taskq_batch_pct = 75;       /* 1 thread per cpu in pset */
 148 id_t            zio_taskq_psrset_bind = PS_NONE;
 149 boolean_t       zio_taskq_sysdc = B_TRUE;       /* use SDC scheduling class */
 150 uint_t          zio_taskq_basedc = 80;          /* base duty cycle */
 151 
 152 boolean_t       spa_create_process = B_TRUE;    /* no process ==> no sysdc */
 153 extern int      zfs_sync_pass_deferred_free;
 154 
 155 /*
 156  * This (illegal) pool name is used when temporarily importing a spa_t in order
 157  * to get the vdev stats associated with the imported devices.
 158  */
 159 #define TRYIMPORT_NAME  "$import"
 160 
 161 /*
 162  * ==========================================================================
 163  * SPA properties routines
 164  * ==========================================================================
 165  */
 166 
 167 /*
 168  * Add a (source=src, propname=propval) list to an nvlist.
 169  */
 170 static void
 171 spa_prop_add_list(nvlist_t *nvl, zpool_prop_t prop, char *strval,
 172     uint64_t intval, zprop_source_t src)
 173 {
 174         const char *propname = zpool_prop_to_name(prop);
 175         nvlist_t *propval;
 176 
 177         VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 178         VERIFY(nvlist_add_uint64(propval, ZPROP_SOURCE, src) == 0);
 179 
 180         if (strval != NULL)
 181                 VERIFY(nvlist_add_string(propval, ZPROP_VALUE, strval) == 0);
 182         else
 183                 VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, intval) == 0);
 184 
 185         VERIFY(nvlist_add_nvlist(nvl, propname, propval) == 0);
 186         nvlist_free(propval);
 187 }
 188 
 189 /*
 190  * Get property values from the spa configuration.
 191  */
 192 static void
 193 spa_prop_get_config(spa_t *spa, nvlist_t **nvp)
 194 {
 195         vdev_t *rvd = spa->spa_root_vdev;
 196         dsl_pool_t *pool = spa->spa_dsl_pool;
 197         uint64_t size;
 198         uint64_t alloc;
 199         uint64_t space;
 200         uint64_t cap, version;
 201         zprop_source_t src = ZPROP_SRC_NONE;
 202         spa_config_dirent_t *dp;
 203 
 204         ASSERT(MUTEX_HELD(&spa->spa_props_lock));
 205 
 206         if (rvd != NULL) {
 207                 alloc = metaslab_class_get_alloc(spa_normal_class(spa));
 208                 size = metaslab_class_get_space(spa_normal_class(spa));
 209                 spa_prop_add_list(*nvp, ZPOOL_PROP_NAME, spa_name(spa), 0, src);
 210                 spa_prop_add_list(*nvp, ZPOOL_PROP_SIZE, NULL, size, src);
 211                 spa_prop_add_list(*nvp, ZPOOL_PROP_ALLOCATED, NULL, alloc, src);
 212                 spa_prop_add_list(*nvp, ZPOOL_PROP_FREE, NULL,
 213                     size - alloc, src);
 214 
 215                 space = 0;
 216                 for (int c = 0; c < rvd->vdev_children; c++) {
 217                         vdev_t *tvd = rvd->vdev_child[c];
 218                         space += tvd->vdev_max_asize - tvd->vdev_asize;
 219                 }
 220                 spa_prop_add_list(*nvp, ZPOOL_PROP_EXPANDSZ, NULL, space,
 221                     src);
 222 
 223                 spa_prop_add_list(*nvp, ZPOOL_PROP_READONLY, NULL,
 224                     (spa_mode(spa) == FREAD), src);
 225 
 226                 cap = (size == 0) ? 0 : (alloc * 100 / size);
 227                 spa_prop_add_list(*nvp, ZPOOL_PROP_CAPACITY, NULL, cap, src);
 228 
 229                 spa_prop_add_list(*nvp, ZPOOL_PROP_DEDUPRATIO, NULL,
 230                     ddt_get_pool_dedup_ratio(spa), src);
 231 
 232                 spa_prop_add_list(*nvp, ZPOOL_PROP_HEALTH, NULL,
 233                     rvd->vdev_state, src);
 234 
 235                 version = spa_version(spa);
 236                 if (version == zpool_prop_default_numeric(ZPOOL_PROP_VERSION))
 237                         src = ZPROP_SRC_DEFAULT;
 238                 else
 239                         src = ZPROP_SRC_LOCAL;
 240                 spa_prop_add_list(*nvp, ZPOOL_PROP_VERSION, NULL, version, src);
 241         }
 242 
 243         if (pool != NULL) {
 244                 dsl_dir_t *freedir = pool->dp_free_dir;
 245 
 246                 /*
 247                  * The $FREE directory was introduced in SPA_VERSION_DEADLISTS,
 248                  * when opening pools before this version freedir will be NULL.
 249                  */
 250                 if (freedir != NULL) {
 251                         spa_prop_add_list(*nvp, ZPOOL_PROP_FREEING, NULL,
 252                             freedir->dd_phys->dd_used_bytes, src);
 253                 } else {
 254                         spa_prop_add_list(*nvp, ZPOOL_PROP_FREEING,
 255                             NULL, 0, src);
 256                 }
 257         }
 258 
 259         spa_prop_add_list(*nvp, ZPOOL_PROP_GUID, NULL, spa_guid(spa), src);
 260 
 261         if (spa->spa_comment != NULL) {
 262                 spa_prop_add_list(*nvp, ZPOOL_PROP_COMMENT, spa->spa_comment,
 263                     0, ZPROP_SRC_LOCAL);
 264         }
 265 
 266         if (spa->spa_root != NULL)
 267                 spa_prop_add_list(*nvp, ZPOOL_PROP_ALTROOT, spa->spa_root,
 268                     0, ZPROP_SRC_LOCAL);
 269 
 270         if ((dp = list_head(&spa->spa_config_list)) != NULL) {
 271                 if (dp->scd_path == NULL) {
 272                         spa_prop_add_list(*nvp, ZPOOL_PROP_CACHEFILE,
 273                             "none", 0, ZPROP_SRC_LOCAL);
 274                 } else if (strcmp(dp->scd_path, spa_config_path) != 0) {
 275                         spa_prop_add_list(*nvp, ZPOOL_PROP_CACHEFILE,
 276                             dp->scd_path, 0, ZPROP_SRC_LOCAL);
 277                 }
 278         }
 279 }
 280 
 281 /*
 282  * Get zpool property values.
 283  */
 284 int
 285 spa_prop_get(spa_t *spa, nvlist_t **nvp)
 286 {
 287         objset_t *mos = spa->spa_meta_objset;
 288         zap_cursor_t zc;
 289         zap_attribute_t za;
 290         int err;
 291 
 292         VERIFY(nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
 293 
 294         mutex_enter(&spa->spa_props_lock);
 295 
 296         /*
 297          * Get properties from the spa config.
 298          */
 299         spa_prop_get_config(spa, nvp);
 300 
 301         /* If no pool property object, no more prop to get. */
 302         if (mos == NULL || spa->spa_pool_props_object == 0) {
 303                 mutex_exit(&spa->spa_props_lock);
 304                 return (0);
 305         }
 306 
 307         /*
 308          * Get properties from the MOS pool property object.
 309          */
 310         for (zap_cursor_init(&zc, mos, spa->spa_pool_props_object);
 311             (err = zap_cursor_retrieve(&zc, &za)) == 0;
 312             zap_cursor_advance(&zc)) {
 313                 uint64_t intval = 0;
 314                 char *strval = NULL;
 315                 zprop_source_t src = ZPROP_SRC_DEFAULT;
 316                 zpool_prop_t prop;
 317 
 318                 if ((prop = zpool_name_to_prop(za.za_name)) == ZPROP_INVAL)
 319                         continue;
 320 
 321                 switch (za.za_integer_length) {
 322                 case 8:
 323                         /* integer property */
 324                         if (za.za_first_integer !=
 325                             zpool_prop_default_numeric(prop))
 326                                 src = ZPROP_SRC_LOCAL;
 327 
 328                         if (prop == ZPOOL_PROP_BOOTFS) {
 329                                 dsl_pool_t *dp;
 330                                 dsl_dataset_t *ds = NULL;
 331 
 332                                 dp = spa_get_dsl(spa);
 333                                 dsl_pool_config_enter(dp, FTAG);
 334                                 if (err = dsl_dataset_hold_obj(dp,
 335                                     za.za_first_integer, FTAG, &ds)) {
 336                                         dsl_pool_config_exit(dp, FTAG);
 337                                         break;
 338                                 }
 339 
 340                                 strval = kmem_alloc(
 341                                     MAXNAMELEN + strlen(MOS_DIR_NAME) + 1,
 342                                     KM_SLEEP);
 343                                 dsl_dataset_name(ds, strval);
 344                                 dsl_dataset_rele(ds, FTAG);
 345                                 dsl_pool_config_exit(dp, FTAG);
 346                         } else {
 347                                 strval = NULL;
 348                                 intval = za.za_first_integer;
 349                         }
 350 
 351                         spa_prop_add_list(*nvp, prop, strval, intval, src);
 352 
 353                         if (strval != NULL)
 354                                 kmem_free(strval,
 355                                     MAXNAMELEN + strlen(MOS_DIR_NAME) + 1);
 356 
 357                         break;
 358 
 359                 case 1:
 360                         /* string property */
 361                         strval = kmem_alloc(za.za_num_integers, KM_SLEEP);
 362                         err = zap_lookup(mos, spa->spa_pool_props_object,
 363                             za.za_name, 1, za.za_num_integers, strval);
 364                         if (err) {
 365                                 kmem_free(strval, za.za_num_integers);
 366                                 break;
 367                         }
 368                         spa_prop_add_list(*nvp, prop, strval, 0, src);
 369                         kmem_free(strval, za.za_num_integers);
 370                         break;
 371 
 372                 default:
 373                         break;
 374                 }
 375         }
 376         zap_cursor_fini(&zc);
 377         mutex_exit(&spa->spa_props_lock);
 378 out:
 379         if (err && err != ENOENT) {
 380                 nvlist_free(*nvp);
 381                 *nvp = NULL;
 382                 return (err);
 383         }
 384 
 385         return (0);
 386 }
 387 
 388 /*
 389  * Validate the given pool properties nvlist and modify the list
 390  * for the property values to be set.
 391  */
 392 static int
 393 spa_prop_validate(spa_t *spa, nvlist_t *props)
 394 {
 395         nvpair_t *elem;
 396         int error = 0, reset_bootfs = 0;
 397         uint64_t objnum = 0;
 398         boolean_t has_feature = B_FALSE;
 399 
 400         elem = NULL;
 401         while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
 402                 uint64_t intval;
 403                 char *strval, *slash, *check, *fname;
 404                 const char *propname = nvpair_name(elem);
 405                 zpool_prop_t prop = zpool_name_to_prop(propname);
 406 
 407                 switch (prop) {
 408                 case ZPROP_INVAL:
 409                         if (!zpool_prop_feature(propname)) {
 410                                 error = SET_ERROR(EINVAL);
 411                                 break;
 412                         }
 413 
 414                         /*
 415                          * Sanitize the input.
 416                          */
 417                         if (nvpair_type(elem) != DATA_TYPE_UINT64) {
 418                                 error = SET_ERROR(EINVAL);
 419                                 break;
 420                         }
 421 
 422                         if (nvpair_value_uint64(elem, &intval) != 0) {
 423                                 error = SET_ERROR(EINVAL);
 424                                 break;
 425                         }
 426 
 427                         if (intval != 0) {
 428                                 error = SET_ERROR(EINVAL);
 429                                 break;
 430                         }
 431 
 432                         fname = strchr(propname, '@') + 1;
 433                         if (zfeature_lookup_name(fname, NULL) != 0) {
 434                                 error = SET_ERROR(EINVAL);
 435                                 break;
 436                         }
 437 
 438                         has_feature = B_TRUE;
 439                         break;
 440 
 441                 case ZPOOL_PROP_VERSION:
 442                         error = nvpair_value_uint64(elem, &intval);
 443                         if (!error &&
 444                             (intval < spa_version(spa) ||
 445                             intval > SPA_VERSION_BEFORE_FEATURES ||
 446                             has_feature))
 447                                 error = SET_ERROR(EINVAL);
 448                         break;
 449 
 450                 case ZPOOL_PROP_DELEGATION:
 451                 case ZPOOL_PROP_AUTOREPLACE:
 452                 case ZPOOL_PROP_LISTSNAPS:
 453                 case ZPOOL_PROP_AUTOEXPAND:
 454                         error = nvpair_value_uint64(elem, &intval);
 455                         if (!error && intval > 1)
 456                                 error = SET_ERROR(EINVAL);
 457                         break;
 458 
 459                 case ZPOOL_PROP_BOOTFS:
 460                         /*
 461                          * If the pool version is less than SPA_VERSION_BOOTFS,
 462                          * or the pool is still being created (version == 0),
 463                          * the bootfs property cannot be set.
 464                          */
 465                         if (spa_version(spa) < SPA_VERSION_BOOTFS) {
 466                                 error = SET_ERROR(ENOTSUP);
 467                                 break;
 468                         }
 469 
 470                         /*
 471                          * Make sure the vdev config is bootable
 472                          */
 473                         if (!vdev_is_bootable(spa->spa_root_vdev)) {
 474                                 error = SET_ERROR(ENOTSUP);
 475                                 break;
 476                         }
 477 
 478                         reset_bootfs = 1;
 479 
 480                         error = nvpair_value_string(elem, &strval);
 481 
 482                         if (!error) {
 483                                 objset_t *os;
 484                                 uint64_t compress;
 485 
 486                                 if (strval == NULL || strval[0] == '\0') {
 487                                         objnum = zpool_prop_default_numeric(
 488                                             ZPOOL_PROP_BOOTFS);
 489                                         break;
 490                                 }
 491 
 492                                 if (error = dmu_objset_hold(strval, FTAG, &os))
 493                                         break;
 494 
 495                                 /* Must be ZPL and not gzip compressed. */
 496 
 497                                 if (dmu_objset_type(os) != DMU_OST_ZFS) {
 498                                         error = SET_ERROR(ENOTSUP);
 499                                 } else if ((error =
 500                                     dsl_prop_get_int_ds(dmu_objset_ds(os),
 501                                     zfs_prop_to_name(ZFS_PROP_COMPRESSION),
 502                                     &compress)) == 0 &&
 503                                     !BOOTFS_COMPRESS_VALID(compress)) {
 504                                         error = SET_ERROR(ENOTSUP);
 505                                 } else {
 506                                         objnum = dmu_objset_id(os);
 507                                 }
 508                                 dmu_objset_rele(os, FTAG);
 509                         }
 510                         break;
 511 
 512                 case ZPOOL_PROP_FAILUREMODE:
 513                         error = nvpair_value_uint64(elem, &intval);
 514                         if (!error && (intval < ZIO_FAILURE_MODE_WAIT ||
 515                             intval > ZIO_FAILURE_MODE_PANIC))
 516                                 error = SET_ERROR(EINVAL);
 517 
 518                         /*
 519                          * This is a special case which only occurs when
 520                          * the pool has completely failed. This allows
 521                          * the user to change the in-core failmode property
 522                          * without syncing it out to disk (I/Os might
 523                          * currently be blocked). We do this by returning
 524                          * EIO to the caller (spa_prop_set) to trick it
 525                          * into thinking we encountered a property validation
 526                          * error.
 527                          */
 528                         if (!error && spa_suspended(spa)) {
 529                                 spa->spa_failmode = intval;
 530                                 error = SET_ERROR(EIO);
 531                         }
 532                         break;
 533 
 534                 case ZPOOL_PROP_CACHEFILE:
 535                         if ((error = nvpair_value_string(elem, &strval)) != 0)
 536                                 break;
 537 
 538                         if (strval[0] == '\0')
 539                                 break;
 540 
 541                         if (strcmp(strval, "none") == 0)
 542                                 break;
 543 
 544                         if (strval[0] != '/') {
 545                                 error = SET_ERROR(EINVAL);
 546                                 break;
 547                         }
 548 
 549                         slash = strrchr(strval, '/');
 550                         ASSERT(slash != NULL);
 551 
 552                         if (slash[1] == '\0' || strcmp(slash, "/.") == 0 ||
 553                             strcmp(slash, "/..") == 0)
 554                                 error = SET_ERROR(EINVAL);
 555                         break;
 556 
 557                 case ZPOOL_PROP_COMMENT:
 558                         if ((error = nvpair_value_string(elem, &strval)) != 0)
 559                                 break;
 560                         for (check = strval; *check != '\0'; check++) {
 561                                 /*
 562                                  * The kernel doesn't have an easy isprint()
 563                                  * check.  For this kernel check, we merely
 564                                  * check ASCII apart from DEL.  Fix this if
 565                                  * there is an easy-to-use kernel isprint().
 566                                  */
 567                                 if (*check >= 0x7f) {
 568                                         error = SET_ERROR(EINVAL);
 569                                         break;
 570                                 }
 571                                 check++;
 572                         }
 573                         if (strlen(strval) > ZPROP_MAX_COMMENT)
 574                                 error = E2BIG;
 575                         break;
 576 
 577                 case ZPOOL_PROP_DEDUPDITTO:
 578                         if (spa_version(spa) < SPA_VERSION_DEDUP)
 579                                 error = SET_ERROR(ENOTSUP);
 580                         else
 581                                 error = nvpair_value_uint64(elem, &intval);
 582                         if (error == 0 &&
 583                             intval != 0 && intval < ZIO_DEDUPDITTO_MIN)
 584                                 error = SET_ERROR(EINVAL);
 585                         break;
 586                 }
 587 
 588                 if (error)
 589                         break;
 590         }
 591 
 592         if (!error && reset_bootfs) {
 593                 error = nvlist_remove(props,
 594                     zpool_prop_to_name(ZPOOL_PROP_BOOTFS), DATA_TYPE_STRING);
 595 
 596                 if (!error) {
 597                         error = nvlist_add_uint64(props,
 598                             zpool_prop_to_name(ZPOOL_PROP_BOOTFS), objnum);
 599                 }
 600         }
 601 
 602         return (error);
 603 }
 604 
 605 void
 606 spa_configfile_set(spa_t *spa, nvlist_t *nvp, boolean_t need_sync)
 607 {
 608         char *cachefile;
 609         spa_config_dirent_t *dp;
 610 
 611         if (nvlist_lookup_string(nvp, zpool_prop_to_name(ZPOOL_PROP_CACHEFILE),
 612             &cachefile) != 0)
 613                 return;
 614 
 615         dp = kmem_alloc(sizeof (spa_config_dirent_t),
 616             KM_SLEEP);
 617 
 618         if (cachefile[0] == '\0')
 619                 dp->scd_path = spa_strdup(spa_config_path);
 620         else if (strcmp(cachefile, "none") == 0)
 621                 dp->scd_path = NULL;
 622         else
 623                 dp->scd_path = spa_strdup(cachefile);
 624 
 625         list_insert_head(&spa->spa_config_list, dp);
 626         if (need_sync)
 627                 spa_async_request(spa, SPA_ASYNC_CONFIG_UPDATE);
 628 }
 629 
 630 int
 631 spa_prop_set(spa_t *spa, nvlist_t *nvp)
 632 {
 633         int error;
 634         nvpair_t *elem = NULL;
 635         boolean_t need_sync = B_FALSE;
 636 
 637         if ((error = spa_prop_validate(spa, nvp)) != 0)
 638                 return (error);
 639 
 640         while ((elem = nvlist_next_nvpair(nvp, elem)) != NULL) {
 641                 zpool_prop_t prop = zpool_name_to_prop(nvpair_name(elem));
 642 
 643                 if (prop == ZPOOL_PROP_CACHEFILE ||
 644                     prop == ZPOOL_PROP_ALTROOT ||
 645                     prop == ZPOOL_PROP_READONLY)
 646                         continue;
 647 
 648                 if (prop == ZPOOL_PROP_VERSION || prop == ZPROP_INVAL) {
 649                         uint64_t ver;
 650 
 651                         if (prop == ZPOOL_PROP_VERSION) {
 652                                 VERIFY(nvpair_value_uint64(elem, &ver) == 0);
 653                         } else {
 654                                 ASSERT(zpool_prop_feature(nvpair_name(elem)));
 655                                 ver = SPA_VERSION_FEATURES;
 656                                 need_sync = B_TRUE;
 657                         }
 658 
 659                         /* Save time if the version is already set. */
 660                         if (ver == spa_version(spa))
 661                                 continue;
 662 
 663                         /*
 664                          * In addition to the pool directory object, we might
 665                          * create the pool properties object, the features for
 666                          * read object, the features for write object, or the
 667                          * feature descriptions object.
 668                          */
 669                         error = dsl_sync_task(spa->spa_name, NULL,
 670                             spa_sync_version, &ver, 6);
 671                         if (error)
 672                                 return (error);
 673                         continue;
 674                 }
 675 
 676                 need_sync = B_TRUE;
 677                 break;
 678         }
 679 
 680         if (need_sync) {
 681                 return (dsl_sync_task(spa->spa_name, NULL, spa_sync_props,
 682                     nvp, 6));
 683         }
 684 
 685         return (0);
 686 }
 687 
 688 /*
 689  * If the bootfs property value is dsobj, clear it.
 690  */
 691 void
 692 spa_prop_clear_bootfs(spa_t *spa, uint64_t dsobj, dmu_tx_t *tx)
 693 {
 694         if (spa->spa_bootfs == dsobj && spa->spa_pool_props_object != 0) {
 695                 VERIFY(zap_remove(spa->spa_meta_objset,
 696                     spa->spa_pool_props_object,
 697                     zpool_prop_to_name(ZPOOL_PROP_BOOTFS), tx) == 0);
 698                 spa->spa_bootfs = 0;
 699         }
 700 }
 701 
 702 /*ARGSUSED*/
 703 static int
 704 spa_change_guid_check(void *arg, dmu_tx_t *tx)
 705 {
 706         uint64_t *newguid = arg;
 707         spa_t *spa = dmu_tx_pool(tx)->dp_spa;
 708         vdev_t *rvd = spa->spa_root_vdev;
 709         uint64_t vdev_state;
 710 
 711         spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
 712         vdev_state = rvd->vdev_state;
 713         spa_config_exit(spa, SCL_STATE, FTAG);
 714 
 715         if (vdev_state != VDEV_STATE_HEALTHY)
 716                 return (SET_ERROR(ENXIO));
 717 
 718         ASSERT3U(spa_guid(spa), !=, *newguid);
 719 
 720         return (0);
 721 }
 722 
 723 static void
 724 spa_change_guid_sync(void *arg, dmu_tx_t *tx)
 725 {
 726         uint64_t *newguid = arg;
 727         spa_t *spa = dmu_tx_pool(tx)->dp_spa;
 728         uint64_t oldguid;
 729         vdev_t *rvd = spa->spa_root_vdev;
 730 
 731         oldguid = spa_guid(spa);
 732 
 733         spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
 734         rvd->vdev_guid = *newguid;
 735         rvd->vdev_guid_sum += (*newguid - oldguid);
 736         vdev_config_dirty(rvd);
 737         spa_config_exit(spa, SCL_STATE, FTAG);
 738 
 739         spa_history_log_internal(spa, "guid change", tx, "old=%llu new=%llu",
 740             oldguid, *newguid);
 741 }
 742 
 743 /*
 744  * Change the GUID for the pool.  This is done so that we can later
 745  * re-import a pool built from a clone of our own vdevs.  We will modify
 746  * the root vdev's guid, our own pool guid, and then mark all of our
 747  * vdevs dirty.  Note that we must make sure that all our vdevs are
 748  * online when we do this, or else any vdevs that weren't present
 749  * would be orphaned from our pool.  We are also going to issue a
 750  * sysevent to update any watchers.
 751  */
 752 int
 753 spa_change_guid(spa_t *spa)
 754 {
 755         int error;
 756         uint64_t guid;
 757 
 758         mutex_enter(&spa->spa_vdev_top_lock);
 759         mutex_enter(&spa_namespace_lock);
 760         guid = spa_generate_guid(NULL);
 761 
 762         error = dsl_sync_task(spa->spa_name, spa_change_guid_check,
 763             spa_change_guid_sync, &guid, 5);
 764 
 765         if (error == 0) {
 766                 spa_config_sync(spa, B_FALSE, B_TRUE);
 767                 spa_event_notify(spa, NULL, ESC_ZFS_POOL_REGUID);
 768         }
 769 
 770         mutex_exit(&spa_namespace_lock);
 771         mutex_exit(&spa->spa_vdev_top_lock);
 772 
 773         return (error);
 774 }
 775 
 776 /*
 777  * ==========================================================================
 778  * SPA state manipulation (open/create/destroy/import/export)
 779  * ==========================================================================
 780  */
 781 
 782 static int
 783 spa_error_entry_compare(const void *a, const void *b)
 784 {
 785         spa_error_entry_t *sa = (spa_error_entry_t *)a;
 786         spa_error_entry_t *sb = (spa_error_entry_t *)b;
 787         int ret;
 788 
 789         ret = bcmp(&sa->se_bookmark, &sb->se_bookmark,
 790             sizeof (zbookmark_t));
 791 
 792         if (ret < 0)
 793                 return (-1);
 794         else if (ret > 0)
 795                 return (1);
 796         else
 797                 return (0);
 798 }
 799 
 800 /*
 801  * Utility function which retrieves copies of the current logs and
 802  * re-initializes them in the process.
 803  */
 804 void
 805 spa_get_errlists(spa_t *spa, avl_tree_t *last, avl_tree_t *scrub)
 806 {
 807         ASSERT(MUTEX_HELD(&spa->spa_errlist_lock));
 808 
 809         bcopy(&spa->spa_errlist_last, last, sizeof (avl_tree_t));
 810         bcopy(&spa->spa_errlist_scrub, scrub, sizeof (avl_tree_t));
 811 
 812         avl_create(&spa->spa_errlist_scrub,
 813             spa_error_entry_compare, sizeof (spa_error_entry_t),
 814             offsetof(spa_error_entry_t, se_avl));
 815         avl_create(&spa->spa_errlist_last,
 816             spa_error_entry_compare, sizeof (spa_error_entry_t),
 817             offsetof(spa_error_entry_t, se_avl));
 818 }
 819 
 820 static void
 821 spa_taskqs_init(spa_t *spa, zio_type_t t, zio_taskq_type_t q)
 822 {
 823         const zio_taskq_info_t *ztip = &zio_taskqs[t][q];
 824         enum zti_modes mode = ztip->zti_mode;
 825         uint_t value = ztip->zti_value;
 826         uint_t count = ztip->zti_count;
 827         spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q];
 828         char name[32];
 829         uint_t flags = 0;
 830         boolean_t batch = B_FALSE;
 831 
 832         if (mode == ZTI_MODE_NULL) {
 833                 tqs->stqs_count = 0;
 834                 tqs->stqs_taskq = NULL;
 835                 return;
 836         }
 837 
 838         ASSERT3U(count, >, 0);
 839 
 840         tqs->stqs_count = count;
 841         tqs->stqs_taskq = kmem_alloc(count * sizeof (taskq_t *), KM_SLEEP);
 842 
 843         switch (mode) {
 844         case ZTI_MODE_FIXED:
 845                 ASSERT3U(value, >=, 1);
 846                 value = MAX(value, 1);
 847                 break;
 848 
 849         case ZTI_MODE_BATCH:
 850                 batch = B_TRUE;
 851                 flags |= TASKQ_THREADS_CPU_PCT;
 852                 value = zio_taskq_batch_pct;
 853                 break;
 854 
 855         default:
 856                 panic("unrecognized mode for %s_%s taskq (%u:%u) in "
 857                     "spa_activate()",
 858                     zio_type_name[t], zio_taskq_types[q], mode, value);
 859                 break;
 860         }
 861 
 862         for (uint_t i = 0; i < count; i++) {
 863                 taskq_t *tq;
 864 
 865                 if (count > 1) {
 866                         (void) snprintf(name, sizeof (name), "%s_%s_%u",
 867                             zio_type_name[t], zio_taskq_types[q], i);
 868                 } else {
 869                         (void) snprintf(name, sizeof (name), "%s_%s",
 870                             zio_type_name[t], zio_taskq_types[q]);
 871                 }
 872 
 873                 if (zio_taskq_sysdc && spa->spa_proc != &p0) {
 874                         if (batch)
 875                                 flags |= TASKQ_DC_BATCH;
 876 
 877                         tq = taskq_create_sysdc(name, value, 50, INT_MAX,
 878                             spa->spa_proc, zio_taskq_basedc, flags);
 879                 } else {
 880                         pri_t pri = maxclsyspri;
 881                         /*
 882                          * The write issue taskq can be extremely CPU
 883                          * intensive.  Run it at slightly lower priority
 884                          * than the other taskqs.
 885                          */
 886                         if (t == ZIO_TYPE_WRITE && q == ZIO_TASKQ_ISSUE)
 887                                 pri--;
 888 
 889                         tq = taskq_create_proc(name, value, pri, 50,
 890                             INT_MAX, spa->spa_proc, flags);
 891                 }
 892 
 893                 tqs->stqs_taskq[i] = tq;
 894         }
 895 }
 896 
 897 static void
 898 spa_taskqs_fini(spa_t *spa, zio_type_t t, zio_taskq_type_t q)
 899 {
 900         spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q];
 901 
 902         if (tqs->stqs_taskq == NULL) {
 903                 ASSERT0(tqs->stqs_count);
 904                 return;
 905         }
 906 
 907         for (uint_t i = 0; i < tqs->stqs_count; i++) {
 908                 ASSERT3P(tqs->stqs_taskq[i], !=, NULL);
 909                 taskq_destroy(tqs->stqs_taskq[i]);
 910         }
 911 
 912         kmem_free(tqs->stqs_taskq, tqs->stqs_count * sizeof (taskq_t *));
 913         tqs->stqs_taskq = NULL;
 914 }
 915 
 916 /*
 917  * Dispatch a task to the appropriate taskq for the ZFS I/O type and priority.
 918  * Note that a type may have multiple discrete taskqs to avoid lock contention
 919  * on the taskq itself. In that case we choose which taskq at random by using
 920  * the low bits of gethrtime().
 921  */
 922 void
 923 spa_taskq_dispatch_ent(spa_t *spa, zio_type_t t, zio_taskq_type_t q,
 924     task_func_t *func, void *arg, uint_t flags, taskq_ent_t *ent)
 925 {
 926         spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q];
 927         taskq_t *tq;
 928 
 929         ASSERT3P(tqs->stqs_taskq, !=, NULL);
 930         ASSERT3U(tqs->stqs_count, !=, 0);
 931 
 932         if (tqs->stqs_count == 1) {
 933                 tq = tqs->stqs_taskq[0];
 934         } else {
 935                 tq = tqs->stqs_taskq[gethrtime() % tqs->stqs_count];
 936         }
 937 
 938         taskq_dispatch_ent(tq, func, arg, flags, ent);
 939 }
 940 
 941 static void
 942 spa_create_zio_taskqs(spa_t *spa)
 943 {
 944         for (int t = 0; t < ZIO_TYPES; t++) {
 945                 for (int q = 0; q < ZIO_TASKQ_TYPES; q++) {
 946                         spa_taskqs_init(spa, t, q);
 947                 }
 948         }
 949 }
 950 
 951 #ifdef _KERNEL
 952 static void
 953 spa_thread(void *arg)
 954 {
 955         callb_cpr_t cprinfo;
 956 
 957         spa_t *spa = arg;
 958         user_t *pu = PTOU(curproc);
 959 
 960         CALLB_CPR_INIT(&cprinfo, &spa->spa_proc_lock, callb_generic_cpr,
 961             spa->spa_name);
 962 
 963         ASSERT(curproc != &p0);
 964         (void) snprintf(pu->u_psargs, sizeof (pu->u_psargs),
 965             "zpool-%s", spa->spa_name);
 966         (void) strlcpy(pu->u_comm, pu->u_psargs, sizeof (pu->u_comm));
 967 
 968         /* bind this thread to the requested psrset */
 969         if (zio_taskq_psrset_bind != PS_NONE) {
 970                 pool_lock();
 971                 mutex_enter(&cpu_lock);
 972                 mutex_enter(&pidlock);
 973                 mutex_enter(&curproc->p_lock);
 974 
 975                 if (cpupart_bind_thread(curthread, zio_taskq_psrset_bind,
 976                     0, NULL, NULL) == 0)  {
 977                         curthread->t_bind_pset = zio_taskq_psrset_bind;
 978                 } else {
 979                         cmn_err(CE_WARN,
 980                             "Couldn't bind process for zfs pool \"%s\" to "
 981                             "pset %d\n", spa->spa_name, zio_taskq_psrset_bind);
 982                 }
 983 
 984                 mutex_exit(&curproc->p_lock);
 985                 mutex_exit(&pidlock);
 986                 mutex_exit(&cpu_lock);
 987                 pool_unlock();
 988         }
 989 
 990         if (zio_taskq_sysdc) {
 991                 sysdc_thread_enter(curthread, 100, 0);
 992         }
 993 
 994         spa->spa_proc = curproc;
 995         spa->spa_did = curthread->t_did;
 996 
 997         spa_create_zio_taskqs(spa);
 998 
 999         mutex_enter(&spa->spa_proc_lock);
1000         ASSERT(spa->spa_proc_state == SPA_PROC_CREATED);
1001 
1002         spa->spa_proc_state = SPA_PROC_ACTIVE;
1003         cv_broadcast(&spa->spa_proc_cv);
1004 
1005         CALLB_CPR_SAFE_BEGIN(&cprinfo);
1006         while (spa->spa_proc_state == SPA_PROC_ACTIVE)
1007                 cv_wait(&spa->spa_proc_cv, &spa->spa_proc_lock);
1008         CALLB_CPR_SAFE_END(&cprinfo, &spa->spa_proc_lock);
1009 
1010         ASSERT(spa->spa_proc_state == SPA_PROC_DEACTIVATE);
1011         spa->spa_proc_state = SPA_PROC_GONE;
1012         spa->spa_proc = &p0;
1013         cv_broadcast(&spa->spa_proc_cv);
1014         CALLB_CPR_EXIT(&cprinfo);   /* drops spa_proc_lock */
1015 
1016         mutex_enter(&curproc->p_lock);
1017         lwp_exit();
1018 }
1019 #endif
1020 
1021 /*
1022  * Activate an uninitialized pool.
1023  */
1024 static void
1025 spa_activate(spa_t *spa, int mode)
1026 {
1027         ASSERT(spa->spa_state == POOL_STATE_UNINITIALIZED);
1028 
1029         spa->spa_state = POOL_STATE_ACTIVE;
1030         spa->spa_mode = mode;
1031 
1032         spa->spa_normal_class = metaslab_class_create(spa, zfs_metaslab_ops);
1033         spa->spa_log_class = metaslab_class_create(spa, zfs_metaslab_ops);
1034 
1035         /* Try to create a covering process */
1036         mutex_enter(&spa->spa_proc_lock);
1037         ASSERT(spa->spa_proc_state == SPA_PROC_NONE);
1038         ASSERT(spa->spa_proc == &p0);
1039         spa->spa_did = 0;
1040 
1041         /* Only create a process if we're going to be around a while. */
1042         if (spa_create_process && strcmp(spa->spa_name, TRYIMPORT_NAME) != 0) {
1043                 if (newproc(spa_thread, (caddr_t)spa, syscid, maxclsyspri,
1044                     NULL, 0) == 0) {
1045                         spa->spa_proc_state = SPA_PROC_CREATED;
1046                         while (spa->spa_proc_state == SPA_PROC_CREATED) {
1047                                 cv_wait(&spa->spa_proc_cv,
1048                                     &spa->spa_proc_lock);
1049                         }
1050                         ASSERT(spa->spa_proc_state == SPA_PROC_ACTIVE);
1051                         ASSERT(spa->spa_proc != &p0);
1052                         ASSERT(spa->spa_did != 0);
1053                 } else {
1054 #ifdef _KERNEL
1055                         cmn_err(CE_WARN,
1056                             "Couldn't create process for zfs pool \"%s\"\n",
1057                             spa->spa_name);
1058 #endif
1059                 }
1060         }
1061         mutex_exit(&spa->spa_proc_lock);
1062 
1063         /* If we didn't create a process, we need to create our taskqs. */
1064         if (spa->spa_proc == &p0) {
1065                 spa_create_zio_taskqs(spa);
1066         }
1067 
1068         list_create(&spa->spa_config_dirty_list, sizeof (vdev_t),
1069             offsetof(vdev_t, vdev_config_dirty_node));
1070         list_create(&spa->spa_state_dirty_list, sizeof (vdev_t),
1071             offsetof(vdev_t, vdev_state_dirty_node));
1072 
1073         txg_list_create(&spa->spa_vdev_txg_list,
1074             offsetof(struct vdev, vdev_txg_node));
1075 
1076         avl_create(&spa->spa_errlist_scrub,
1077             spa_error_entry_compare, sizeof (spa_error_entry_t),
1078             offsetof(spa_error_entry_t, se_avl));
1079         avl_create(&spa->spa_errlist_last,
1080             spa_error_entry_compare, sizeof (spa_error_entry_t),
1081             offsetof(spa_error_entry_t, se_avl));
1082 }
1083 
1084 /*
1085  * Opposite of spa_activate().
1086  */
1087 static void
1088 spa_deactivate(spa_t *spa)
1089 {
1090         ASSERT(spa->spa_sync_on == B_FALSE);
1091         ASSERT(spa->spa_dsl_pool == NULL);
1092         ASSERT(spa->spa_root_vdev == NULL);
1093         ASSERT(spa->spa_async_zio_root == NULL);
1094         ASSERT(spa->spa_state != POOL_STATE_UNINITIALIZED);
1095 
1096         txg_list_destroy(&spa->spa_vdev_txg_list);
1097 
1098         list_destroy(&spa->spa_config_dirty_list);
1099         list_destroy(&spa->spa_state_dirty_list);
1100 
1101         for (int t = 0; t < ZIO_TYPES; t++) {
1102                 for (int q = 0; q < ZIO_TASKQ_TYPES; q++) {
1103                         spa_taskqs_fini(spa, t, q);
1104                 }
1105         }
1106 
1107         metaslab_class_destroy(spa->spa_normal_class);
1108         spa->spa_normal_class = NULL;
1109 
1110         metaslab_class_destroy(spa->spa_log_class);
1111         spa->spa_log_class = NULL;
1112 
1113         /*
1114          * If this was part of an import or the open otherwise failed, we may
1115          * still have errors left in the queues.  Empty them just in case.
1116          */
1117         spa_errlog_drain(spa);
1118 
1119         avl_destroy(&spa->spa_errlist_scrub);
1120         avl_destroy(&spa->spa_errlist_last);
1121 
1122         spa->spa_state = POOL_STATE_UNINITIALIZED;
1123 
1124         mutex_enter(&spa->spa_proc_lock);
1125         if (spa->spa_proc_state != SPA_PROC_NONE) {
1126                 ASSERT(spa->spa_proc_state == SPA_PROC_ACTIVE);
1127                 spa->spa_proc_state = SPA_PROC_DEACTIVATE;
1128                 cv_broadcast(&spa->spa_proc_cv);
1129                 while (spa->spa_proc_state == SPA_PROC_DEACTIVATE) {
1130                         ASSERT(spa->spa_proc != &p0);
1131                         cv_wait(&spa->spa_proc_cv, &spa->spa_proc_lock);
1132                 }
1133                 ASSERT(spa->spa_proc_state == SPA_PROC_GONE);
1134                 spa->spa_proc_state = SPA_PROC_NONE;
1135         }
1136         ASSERT(spa->spa_proc == &p0);
1137         mutex_exit(&spa->spa_proc_lock);
1138 
1139         /*
1140          * We want to make sure spa_thread() has actually exited the ZFS
1141          * module, so that the module can't be unloaded out from underneath
1142          * it.
1143          */
1144         if (spa->spa_did != 0) {
1145                 thread_join(spa->spa_did);
1146                 spa->spa_did = 0;
1147         }
1148 }
1149 
1150 /*
1151  * Verify a pool configuration, and construct the vdev tree appropriately.  This
1152  * will create all the necessary vdevs in the appropriate layout, with each vdev
1153  * in the CLOSED state.  This will prep the pool before open/creation/import.
1154  * All vdev validation is done by the vdev_alloc() routine.
1155  */
1156 static int
1157 spa_config_parse(spa_t *spa, vdev_t **vdp, nvlist_t *nv, vdev_t *parent,
1158     uint_t id, int atype)
1159 {
1160         nvlist_t **child;
1161         uint_t children;
1162         int error;
1163 
1164         if ((error = vdev_alloc(spa, vdp, nv, parent, id, atype)) != 0)
1165                 return (error);
1166 
1167         if ((*vdp)->vdev_ops->vdev_op_leaf)
1168                 return (0);
1169 
1170         error = nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
1171             &child, &children);
1172 
1173         if (error == ENOENT)
1174                 return (0);
1175 
1176         if (error) {
1177                 vdev_free(*vdp);
1178                 *vdp = NULL;
1179                 return (SET_ERROR(EINVAL));
1180         }
1181 
1182         for (int c = 0; c < children; c++) {
1183                 vdev_t *vd;
1184                 if ((error = spa_config_parse(spa, &vd, child[c], *vdp, c,
1185                     atype)) != 0) {
1186                         vdev_free(*vdp);
1187                         *vdp = NULL;
1188                         return (error);
1189                 }
1190         }
1191 
1192         ASSERT(*vdp != NULL);
1193 
1194         return (0);
1195 }
1196 
1197 /*
1198  * Opposite of spa_load().
1199  */
1200 static void
1201 spa_unload(spa_t *spa)
1202 {
1203         int i;
1204 
1205         ASSERT(MUTEX_HELD(&spa_namespace_lock));
1206 
1207         /*
1208          * Stop async tasks.
1209          */
1210         spa_async_suspend(spa);
1211 
1212         /*
1213          * Stop syncing.
1214          */
1215         if (spa->spa_sync_on) {
1216                 txg_sync_stop(spa->spa_dsl_pool);
1217                 spa->spa_sync_on = B_FALSE;
1218         }
1219 
1220         /*
1221          * Wait for any outstanding async I/O to complete.
1222          */
1223         if (spa->spa_async_zio_root != NULL) {
1224                 (void) zio_wait(spa->spa_async_zio_root);
1225                 spa->spa_async_zio_root = NULL;
1226         }
1227 
1228         bpobj_close(&spa->spa_deferred_bpobj);
1229 
1230         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1231 
1232         /*
1233          * Close all vdevs.
1234          */
1235         if (spa->spa_root_vdev)
1236                 vdev_free(spa->spa_root_vdev);
1237         ASSERT(spa->spa_root_vdev == NULL);
1238 
1239         /*
1240          * Close the dsl pool.
1241          */
1242         if (spa->spa_dsl_pool) {
1243                 dsl_pool_close(spa->spa_dsl_pool);
1244                 spa->spa_dsl_pool = NULL;
1245                 spa->spa_meta_objset = NULL;
1246         }
1247 
1248         ddt_unload(spa);
1249 
1250 
1251         /*
1252          * Drop and purge level 2 cache
1253          */
1254         spa_l2cache_drop(spa);
1255 
1256         for (i = 0; i < spa->spa_spares.sav_count; i++)
1257                 vdev_free(spa->spa_spares.sav_vdevs[i]);
1258         if (spa->spa_spares.sav_vdevs) {
1259                 kmem_free(spa->spa_spares.sav_vdevs,
1260                     spa->spa_spares.sav_count * sizeof (void *));
1261                 spa->spa_spares.sav_vdevs = NULL;
1262         }
1263         if (spa->spa_spares.sav_config) {
1264                 nvlist_free(spa->spa_spares.sav_config);
1265                 spa->spa_spares.sav_config = NULL;
1266         }
1267         spa->spa_spares.sav_count = 0;
1268 
1269         for (i = 0; i < spa->spa_l2cache.sav_count; i++) {
1270                 vdev_clear_stats(spa->spa_l2cache.sav_vdevs[i]);
1271                 vdev_free(spa->spa_l2cache.sav_vdevs[i]);
1272         }
1273         if (spa->spa_l2cache.sav_vdevs) {
1274                 kmem_free(spa->spa_l2cache.sav_vdevs,
1275                     spa->spa_l2cache.sav_count * sizeof (void *));
1276                 spa->spa_l2cache.sav_vdevs = NULL;
1277         }
1278         if (spa->spa_l2cache.sav_config) {
1279                 nvlist_free(spa->spa_l2cache.sav_config);
1280                 spa->spa_l2cache.sav_config = NULL;
1281         }
1282         spa->spa_l2cache.sav_count = 0;
1283 
1284         spa->spa_async_suspended = 0;
1285 
1286         if (spa->spa_comment != NULL) {
1287                 spa_strfree(spa->spa_comment);
1288                 spa->spa_comment = NULL;
1289         }
1290 
1291         spa_config_exit(spa, SCL_ALL, FTAG);
1292 }
1293 
1294 /*
1295  * Load (or re-load) the current list of vdevs describing the active spares for
1296  * this pool.  When this is called, we have some form of basic information in
1297  * 'spa_spares.sav_config'.  We parse this into vdevs, try to open them, and
1298  * then re-generate a more complete list including status information.
1299  */
1300 static void
1301 spa_load_spares(spa_t *spa)
1302 {
1303         nvlist_t **spares;
1304         uint_t nspares;
1305         int i;
1306         vdev_t *vd, *tvd;
1307 
1308         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1309 
1310         /*
1311          * First, close and free any existing spare vdevs.
1312          */
1313         for (i = 0; i < spa->spa_spares.sav_count; i++) {
1314                 vd = spa->spa_spares.sav_vdevs[i];
1315 
1316                 /* Undo the call to spa_activate() below */
1317                 if ((tvd = spa_lookup_by_guid(spa, vd->vdev_guid,
1318                     B_FALSE)) != NULL && tvd->vdev_isspare)
1319                         spa_spare_remove(tvd);
1320                 vdev_close(vd);
1321                 vdev_free(vd);
1322         }
1323 
1324         if (spa->spa_spares.sav_vdevs)
1325                 kmem_free(spa->spa_spares.sav_vdevs,
1326                     spa->spa_spares.sav_count * sizeof (void *));
1327 
1328         if (spa->spa_spares.sav_config == NULL)
1329                 nspares = 0;
1330         else
1331                 VERIFY(nvlist_lookup_nvlist_array(spa->spa_spares.sav_config,
1332                     ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0);
1333 
1334         spa->spa_spares.sav_count = (int)nspares;
1335         spa->spa_spares.sav_vdevs = NULL;
1336 
1337         if (nspares == 0)
1338                 return;
1339 
1340         /*
1341          * Construct the array of vdevs, opening them to get status in the
1342          * process.   For each spare, there is potentially two different vdev_t
1343          * structures associated with it: one in the list of spares (used only
1344          * for basic validation purposes) and one in the active vdev
1345          * configuration (if it's spared in).  During this phase we open and
1346          * validate each vdev on the spare list.  If the vdev also exists in the
1347          * active configuration, then we also mark this vdev as an active spare.
1348          */
1349         spa->spa_spares.sav_vdevs = kmem_alloc(nspares * sizeof (void *),
1350             KM_SLEEP);
1351         for (i = 0; i < spa->spa_spares.sav_count; i++) {
1352                 VERIFY(spa_config_parse(spa, &vd, spares[i], NULL, 0,
1353                     VDEV_ALLOC_SPARE) == 0);
1354                 ASSERT(vd != NULL);
1355 
1356                 spa->spa_spares.sav_vdevs[i] = vd;
1357 
1358                 if ((tvd = spa_lookup_by_guid(spa, vd->vdev_guid,
1359                     B_FALSE)) != NULL) {
1360                         if (!tvd->vdev_isspare)
1361                                 spa_spare_add(tvd);
1362 
1363                         /*
1364                          * We only mark the spare active if we were successfully
1365                          * able to load the vdev.  Otherwise, importing a pool
1366                          * with a bad active spare would result in strange
1367                          * behavior, because multiple pool would think the spare
1368                          * is actively in use.
1369                          *
1370                          * There is a vulnerability here to an equally bizarre
1371                          * circumstance, where a dead active spare is later
1372                          * brought back to life (onlined or otherwise).  Given
1373                          * the rarity of this scenario, and the extra complexity
1374                          * it adds, we ignore the possibility.
1375                          */
1376                         if (!vdev_is_dead(tvd))
1377                                 spa_spare_activate(tvd);
1378                 }
1379 
1380                 vd->vdev_top = vd;
1381                 vd->vdev_aux = &spa->spa_spares;
1382 
1383                 if (vdev_open(vd) != 0)
1384                         continue;
1385 
1386                 if (vdev_validate_aux(vd) == 0)
1387                         spa_spare_add(vd);
1388         }
1389 
1390         /*
1391          * Recompute the stashed list of spares, with status information
1392          * this time.
1393          */
1394         VERIFY(nvlist_remove(spa->spa_spares.sav_config, ZPOOL_CONFIG_SPARES,
1395             DATA_TYPE_NVLIST_ARRAY) == 0);
1396 
1397         spares = kmem_alloc(spa->spa_spares.sav_count * sizeof (void *),
1398             KM_SLEEP);
1399         for (i = 0; i < spa->spa_spares.sav_count; i++)
1400                 spares[i] = vdev_config_generate(spa,
1401                     spa->spa_spares.sav_vdevs[i], B_TRUE, VDEV_CONFIG_SPARE);
1402         VERIFY(nvlist_add_nvlist_array(spa->spa_spares.sav_config,
1403             ZPOOL_CONFIG_SPARES, spares, spa->spa_spares.sav_count) == 0);
1404         for (i = 0; i < spa->spa_spares.sav_count; i++)
1405                 nvlist_free(spares[i]);
1406         kmem_free(spares, spa->spa_spares.sav_count * sizeof (void *));
1407 }
1408 
1409 /*
1410  * Load (or re-load) the current list of vdevs describing the active l2cache for
1411  * this pool.  When this is called, we have some form of basic information in
1412  * 'spa_l2cache.sav_config'.  We parse this into vdevs, try to open them, and
1413  * then re-generate a more complete list including status information.
1414  * Devices which are already active have their details maintained, and are
1415  * not re-opened.
1416  */
1417 static void
1418 spa_load_l2cache(spa_t *spa)
1419 {
1420         nvlist_t **l2cache;
1421         uint_t nl2cache;
1422         int i, j, oldnvdevs;
1423         uint64_t guid;
1424         vdev_t *vd, **oldvdevs, **newvdevs;
1425         spa_aux_vdev_t *sav = &spa->spa_l2cache;
1426 
1427         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1428 
1429         if (sav->sav_config != NULL) {
1430                 VERIFY(nvlist_lookup_nvlist_array(sav->sav_config,
1431                     ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0);
1432                 newvdevs = kmem_alloc(nl2cache * sizeof (void *), KM_SLEEP);
1433         } else {
1434                 nl2cache = 0;
1435                 newvdevs = NULL;
1436         }
1437 
1438         oldvdevs = sav->sav_vdevs;
1439         oldnvdevs = sav->sav_count;
1440         sav->sav_vdevs = NULL;
1441         sav->sav_count = 0;
1442 
1443         /*
1444          * Process new nvlist of vdevs.
1445          */
1446         for (i = 0; i < nl2cache; i++) {
1447                 VERIFY(nvlist_lookup_uint64(l2cache[i], ZPOOL_CONFIG_GUID,
1448                     &guid) == 0);
1449 
1450                 newvdevs[i] = NULL;
1451                 for (j = 0; j < oldnvdevs; j++) {
1452                         vd = oldvdevs[j];
1453                         if (vd != NULL && guid == vd->vdev_guid) {
1454                                 /*
1455                                  * Retain previous vdev for add/remove ops.
1456                                  */
1457                                 newvdevs[i] = vd;
1458                                 oldvdevs[j] = NULL;
1459                                 break;
1460                         }
1461                 }
1462 
1463                 if (newvdevs[i] == NULL) {
1464                         /*
1465                          * Create new vdev
1466                          */
1467                         VERIFY(spa_config_parse(spa, &vd, l2cache[i], NULL, 0,
1468                             VDEV_ALLOC_L2CACHE) == 0);
1469                         ASSERT(vd != NULL);
1470                         newvdevs[i] = vd;
1471 
1472                         /*
1473                          * Commit this vdev as an l2cache device,
1474                          * even if it fails to open.
1475                          */
1476                         spa_l2cache_add(vd);
1477 
1478                         vd->vdev_top = vd;
1479                         vd->vdev_aux = sav;
1480 
1481                         spa_l2cache_activate(vd);
1482 
1483                         if (vdev_open(vd) != 0)
1484                                 continue;
1485 
1486                         (void) vdev_validate_aux(vd);
1487 
1488                         if (!vdev_is_dead(vd))
1489                                 l2arc_add_vdev(spa, vd);
1490                 }
1491         }
1492 
1493         /*
1494          * Purge vdevs that were dropped
1495          */
1496         for (i = 0; i < oldnvdevs; i++) {
1497                 uint64_t pool;
1498 
1499                 vd = oldvdevs[i];
1500                 if (vd != NULL) {
1501                         ASSERT(vd->vdev_isl2cache);
1502 
1503                         if (spa_l2cache_exists(vd->vdev_guid, &pool) &&
1504                             pool != 0ULL && l2arc_vdev_present(vd))
1505                                 l2arc_remove_vdev(vd);
1506                         vdev_clear_stats(vd);
1507                         vdev_free(vd);
1508                 }
1509         }
1510 
1511         if (oldvdevs)
1512                 kmem_free(oldvdevs, oldnvdevs * sizeof (void *));
1513 
1514         if (sav->sav_config == NULL)
1515                 goto out;
1516 
1517         sav->sav_vdevs = newvdevs;
1518         sav->sav_count = (int)nl2cache;
1519 
1520         /*
1521          * Recompute the stashed list of l2cache devices, with status
1522          * information this time.
1523          */
1524         VERIFY(nvlist_remove(sav->sav_config, ZPOOL_CONFIG_L2CACHE,
1525             DATA_TYPE_NVLIST_ARRAY) == 0);
1526 
1527         l2cache = kmem_alloc(sav->sav_count * sizeof (void *), KM_SLEEP);
1528         for (i = 0; i < sav->sav_count; i++)
1529                 l2cache[i] = vdev_config_generate(spa,
1530                     sav->sav_vdevs[i], B_TRUE, VDEV_CONFIG_L2CACHE);
1531         VERIFY(nvlist_add_nvlist_array(sav->sav_config,
1532             ZPOOL_CONFIG_L2CACHE, l2cache, sav->sav_count) == 0);
1533 out:
1534         for (i = 0; i < sav->sav_count; i++)
1535                 nvlist_free(l2cache[i]);
1536         if (sav->sav_count)
1537                 kmem_free(l2cache, sav->sav_count * sizeof (void *));
1538 }
1539 
1540 static int
1541 load_nvlist(spa_t *spa, uint64_t obj, nvlist_t **value)
1542 {
1543         dmu_buf_t *db;
1544         char *packed = NULL;
1545         size_t nvsize = 0;
1546         int error;
1547         *value = NULL;
1548 
1549         VERIFY(0 == dmu_bonus_hold(spa->spa_meta_objset, obj, FTAG, &db));
1550         nvsize = *(uint64_t *)db->db_data;
1551         dmu_buf_rele(db, FTAG);
1552 
1553         packed = kmem_alloc(nvsize, KM_SLEEP);
1554         error = dmu_read(spa->spa_meta_objset, obj, 0, nvsize, packed,
1555             DMU_READ_PREFETCH);
1556         if (error == 0)
1557                 error = nvlist_unpack(packed, nvsize, value, 0);
1558         kmem_free(packed, nvsize);
1559 
1560         return (error);
1561 }
1562 
1563 /*
1564  * Checks to see if the given vdev could not be opened, in which case we post a
1565  * sysevent to notify the autoreplace code that the device has been removed.
1566  */
1567 static void
1568 spa_check_removed(vdev_t *vd)
1569 {
1570         for (int c = 0; c < vd->vdev_children; c++)
1571                 spa_check_removed(vd->vdev_child[c]);
1572 
1573         if (vd->vdev_ops->vdev_op_leaf && vdev_is_dead(vd) &&
1574             !vd->vdev_ishole) {
1575                 zfs_post_autoreplace(vd->vdev_spa, vd);
1576                 spa_event_notify(vd->vdev_spa, vd, ESC_ZFS_VDEV_CHECK);
1577         }
1578 }
1579 
1580 /*
1581  * Validate the current config against the MOS config
1582  */
1583 static boolean_t
1584 spa_config_valid(spa_t *spa, nvlist_t *config)
1585 {
1586         vdev_t *mrvd, *rvd = spa->spa_root_vdev;
1587         nvlist_t *nv;
1588 
1589         VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nv) == 0);
1590 
1591         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1592         VERIFY(spa_config_parse(spa, &mrvd, nv, NULL, 0, VDEV_ALLOC_LOAD) == 0);
1593 
1594         ASSERT3U(rvd->vdev_children, ==, mrvd->vdev_children);
1595 
1596         /*
1597          * If we're doing a normal import, then build up any additional
1598          * diagnostic information about missing devices in this config.
1599          * We'll pass this up to the user for further processing.
1600          */
1601         if (!(spa->spa_import_flags & ZFS_IMPORT_MISSING_LOG)) {
1602                 nvlist_t **child, *nv;
1603                 uint64_t idx = 0;
1604 
1605                 child = kmem_alloc(rvd->vdev_children * sizeof (nvlist_t **),
1606                     KM_SLEEP);
1607                 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1608 
1609                 for (int c = 0; c < rvd->vdev_children; c++) {
1610                         vdev_t *tvd = rvd->vdev_child[c];
1611                         vdev_t *mtvd  = mrvd->vdev_child[c];
1612 
1613                         if (tvd->vdev_ops == &vdev_missing_ops &&
1614                             mtvd->vdev_ops != &vdev_missing_ops &&
1615                             mtvd->vdev_islog)
1616                                 child[idx++] = vdev_config_generate(spa, mtvd,
1617                                     B_FALSE, 0);
1618                 }
1619 
1620                 if (idx) {
1621                         VERIFY(nvlist_add_nvlist_array(nv,
1622                             ZPOOL_CONFIG_CHILDREN, child, idx) == 0);
1623                         VERIFY(nvlist_add_nvlist(spa->spa_load_info,
1624                             ZPOOL_CONFIG_MISSING_DEVICES, nv) == 0);
1625 
1626                         for (int i = 0; i < idx; i++)
1627                                 nvlist_free(child[i]);
1628                 }
1629                 nvlist_free(nv);
1630                 kmem_free(child, rvd->vdev_children * sizeof (char **));
1631         }
1632 
1633         /*
1634          * Compare the root vdev tree with the information we have
1635          * from the MOS config (mrvd). Check each top-level vdev
1636          * with the corresponding MOS config top-level (mtvd).
1637          */
1638         for (int c = 0; c < rvd->vdev_children; c++) {
1639                 vdev_t *tvd = rvd->vdev_child[c];
1640                 vdev_t *mtvd  = mrvd->vdev_child[c];
1641 
1642                 /*
1643                  * Resolve any "missing" vdevs in the current configuration.
1644                  * If we find that the MOS config has more accurate information
1645                  * about the top-level vdev then use that vdev instead.
1646                  */
1647                 if (tvd->vdev_ops == &vdev_missing_ops &&
1648                     mtvd->vdev_ops != &vdev_missing_ops) {
1649 
1650                         if (!(spa->spa_import_flags & ZFS_IMPORT_MISSING_LOG))
1651                                 continue;
1652 
1653                         /*
1654                          * Device specific actions.
1655                          */
1656                         if (mtvd->vdev_islog) {
1657                                 spa_set_log_state(spa, SPA_LOG_CLEAR);
1658                         } else {
1659                                 /*
1660                                  * XXX - once we have 'readonly' pool
1661                                  * support we should be able to handle
1662                                  * missing data devices by transitioning
1663                                  * the pool to readonly.
1664                                  */
1665                                 continue;
1666                         }
1667 
1668                         /*
1669                          * Swap the missing vdev with the data we were
1670                          * able to obtain from the MOS config.
1671                          */
1672                         vdev_remove_child(rvd, tvd);
1673                         vdev_remove_child(mrvd, mtvd);
1674 
1675                         vdev_add_child(rvd, mtvd);
1676                         vdev_add_child(mrvd, tvd);
1677 
1678                         spa_config_exit(spa, SCL_ALL, FTAG);
1679                         vdev_load(mtvd);
1680                         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1681 
1682                         vdev_reopen(rvd);
1683                 } else if (mtvd->vdev_islog) {
1684                         /*
1685                          * Load the slog device's state from the MOS config
1686                          * since it's possible that the label does not
1687                          * contain the most up-to-date information.
1688                          */
1689                         vdev_load_log_state(tvd, mtvd);
1690                         vdev_reopen(tvd);
1691                 }
1692         }
1693         vdev_free(mrvd);
1694         spa_config_exit(spa, SCL_ALL, FTAG);
1695 
1696         /*
1697          * Ensure we were able to validate the config.
1698          */
1699         return (rvd->vdev_guid_sum == spa->spa_uberblock.ub_guid_sum);
1700 }
1701 
1702 /*
1703  * Check for missing log devices
1704  */
1705 static boolean_t
1706 spa_check_logs(spa_t *spa)
1707 {
1708         boolean_t rv = B_FALSE;
1709 
1710         switch (spa->spa_log_state) {
1711         case SPA_LOG_MISSING:
1712                 /* need to recheck in case slog has been restored */
1713         case SPA_LOG_UNKNOWN:
1714                 rv = (dmu_objset_find(spa->spa_name, zil_check_log_chain,
1715                     NULL, DS_FIND_CHILDREN) != 0);
1716                 if (rv)
1717                         spa_set_log_state(spa, SPA_LOG_MISSING);
1718                 break;
1719         }
1720         return (rv);
1721 }
1722 
1723 static boolean_t
1724 spa_passivate_log(spa_t *spa)
1725 {
1726         vdev_t *rvd = spa->spa_root_vdev;
1727         boolean_t slog_found = B_FALSE;
1728 
1729         ASSERT(spa_config_held(spa, SCL_ALLOC, RW_WRITER));
1730 
1731         if (!spa_has_slogs(spa))
1732                 return (B_FALSE);
1733 
1734         for (int c = 0; c < rvd->vdev_children; c++) {
1735                 vdev_t *tvd = rvd->vdev_child[c];
1736                 metaslab_group_t *mg = tvd->vdev_mg;
1737 
1738                 if (tvd->vdev_islog) {
1739                         metaslab_group_passivate(mg);
1740                         slog_found = B_TRUE;
1741                 }
1742         }
1743 
1744         return (slog_found);
1745 }
1746 
1747 static void
1748 spa_activate_log(spa_t *spa)
1749 {
1750         vdev_t *rvd = spa->spa_root_vdev;
1751 
1752         ASSERT(spa_config_held(spa, SCL_ALLOC, RW_WRITER));
1753 
1754         for (int c = 0; c < rvd->vdev_children; c++) {
1755                 vdev_t *tvd = rvd->vdev_child[c];
1756                 metaslab_group_t *mg = tvd->vdev_mg;
1757 
1758                 if (tvd->vdev_islog)
1759                         metaslab_group_activate(mg);
1760         }
1761 }
1762 
1763 int
1764 spa_offline_log(spa_t *spa)
1765 {
1766         int error;
1767 
1768         error = dmu_objset_find(spa_name(spa), zil_vdev_offline,
1769             NULL, DS_FIND_CHILDREN);
1770         if (error == 0) {
1771                 /*
1772                  * We successfully offlined the log device, sync out the
1773                  * current txg so that the "stubby" block can be removed
1774                  * by zil_sync().
1775                  */
1776                 txg_wait_synced(spa->spa_dsl_pool, 0);
1777         }
1778         return (error);
1779 }
1780 
1781 static void
1782 spa_aux_check_removed(spa_aux_vdev_t *sav)
1783 {
1784         for (int i = 0; i < sav->sav_count; i++)
1785                 spa_check_removed(sav->sav_vdevs[i]);
1786 }
1787 
1788 void
1789 spa_claim_notify(zio_t *zio)
1790 {
1791         spa_t *spa = zio->io_spa;
1792 
1793         if (zio->io_error)
1794                 return;
1795 
1796         mutex_enter(&spa->spa_props_lock);       /* any mutex will do */
1797         if (spa->spa_claim_max_txg < zio->io_bp->blk_birth)
1798                 spa->spa_claim_max_txg = zio->io_bp->blk_birth;
1799         mutex_exit(&spa->spa_props_lock);
1800 }
1801 
1802 typedef struct spa_load_error {
1803         uint64_t        sle_meta_count;
1804         uint64_t        sle_data_count;
1805 } spa_load_error_t;
1806 
1807 static void
1808 spa_load_verify_done(zio_t *zio)
1809 {
1810         blkptr_t *bp = zio->io_bp;
1811         spa_load_error_t *sle = zio->io_private;
1812         dmu_object_type_t type = BP_GET_TYPE(bp);
1813         int error = zio->io_error;
1814 
1815         if (error) {
1816                 if ((BP_GET_LEVEL(bp) != 0 || DMU_OT_IS_METADATA(type)) &&
1817                     type != DMU_OT_INTENT_LOG)
1818                         atomic_add_64(&sle->sle_meta_count, 1);
1819                 else
1820                         atomic_add_64(&sle->sle_data_count, 1);
1821         }
1822         zio_data_buf_free(zio->io_data, zio->io_size);
1823 }
1824 
1825 /*ARGSUSED*/
1826 static int
1827 spa_load_verify_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
1828     const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
1829 {
1830         if (!BP_IS_HOLE(bp)) {
1831                 zio_t *rio = arg;
1832                 size_t size = BP_GET_PSIZE(bp);
1833                 void *data = zio_data_buf_alloc(size);
1834 
1835                 zio_nowait(zio_read(rio, spa, bp, data, size,
1836                     spa_load_verify_done, rio->io_private, ZIO_PRIORITY_SCRUB,
1837                     ZIO_FLAG_SPECULATIVE | ZIO_FLAG_CANFAIL |
1838                     ZIO_FLAG_SCRUB | ZIO_FLAG_RAW, zb));
1839         }
1840         return (0);
1841 }
1842 
1843 static int
1844 spa_load_verify(spa_t *spa)
1845 {
1846         zio_t *rio;
1847         spa_load_error_t sle = { 0 };
1848         zpool_rewind_policy_t policy;
1849         boolean_t verify_ok = B_FALSE;
1850         int error;
1851 
1852         zpool_get_rewind_policy(spa->spa_config, &policy);
1853 
1854         if (policy.zrp_request & ZPOOL_NEVER_REWIND)
1855                 return (0);
1856 
1857         rio = zio_root(spa, NULL, &sle,
1858             ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE);
1859 
1860         error = traverse_pool(spa, spa->spa_verify_min_txg,
1861             TRAVERSE_PRE | TRAVERSE_PREFETCH, spa_load_verify_cb, rio);
1862 
1863         (void) zio_wait(rio);
1864 
1865         spa->spa_load_meta_errors = sle.sle_meta_count;
1866         spa->spa_load_data_errors = sle.sle_data_count;
1867 
1868         if (!error && sle.sle_meta_count <= policy.zrp_maxmeta &&
1869             sle.sle_data_count <= policy.zrp_maxdata) {
1870                 int64_t loss = 0;
1871 
1872                 verify_ok = B_TRUE;
1873                 spa->spa_load_txg = spa->spa_uberblock.ub_txg;
1874                 spa->spa_load_txg_ts = spa->spa_uberblock.ub_timestamp;
1875 
1876                 loss = spa->spa_last_ubsync_txg_ts - spa->spa_load_txg_ts;
1877                 VERIFY(nvlist_add_uint64(spa->spa_load_info,
1878                     ZPOOL_CONFIG_LOAD_TIME, spa->spa_load_txg_ts) == 0);
1879                 VERIFY(nvlist_add_int64(spa->spa_load_info,
1880                     ZPOOL_CONFIG_REWIND_TIME, loss) == 0);
1881                 VERIFY(nvlist_add_uint64(spa->spa_load_info,
1882                     ZPOOL_CONFIG_LOAD_DATA_ERRORS, sle.sle_data_count) == 0);
1883         } else {
1884                 spa->spa_load_max_txg = spa->spa_uberblock.ub_txg;
1885         }
1886 
1887         if (error) {
1888                 if (error != ENXIO && error != EIO)
1889                         error = SET_ERROR(EIO);
1890                 return (error);
1891         }
1892 
1893         return (verify_ok ? 0 : EIO);
1894 }
1895 
1896 /*
1897  * Find a value in the pool props object.
1898  */
1899 static void
1900 spa_prop_find(spa_t *spa, zpool_prop_t prop, uint64_t *val)
1901 {
1902         (void) zap_lookup(spa->spa_meta_objset, spa->spa_pool_props_object,
1903             zpool_prop_to_name(prop), sizeof (uint64_t), 1, val);
1904 }
1905 
1906 /*
1907  * Find a value in the pool directory object.
1908  */
1909 static int
1910 spa_dir_prop(spa_t *spa, const char *name, uint64_t *val)
1911 {
1912         return (zap_lookup(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
1913             name, sizeof (uint64_t), 1, val));
1914 }
1915 
1916 static int
1917 spa_vdev_err(vdev_t *vdev, vdev_aux_t aux, int err)
1918 {
1919         vdev_set_state(vdev, B_TRUE, VDEV_STATE_CANT_OPEN, aux);
1920         return (err);
1921 }
1922 
1923 /*
1924  * Fix up config after a partly-completed split.  This is done with the
1925  * ZPOOL_CONFIG_SPLIT nvlist.  Both the splitting pool and the split-off
1926  * pool have that entry in their config, but only the splitting one contains
1927  * a list of all the guids of the vdevs that are being split off.
1928  *
1929  * This function determines what to do with that list: either rejoin
1930  * all the disks to the pool, or complete the splitting process.  To attempt
1931  * the rejoin, each disk that is offlined is marked online again, and
1932  * we do a reopen() call.  If the vdev label for every disk that was
1933  * marked online indicates it was successfully split off (VDEV_AUX_SPLIT_POOL)
1934  * then we call vdev_split() on each disk, and complete the split.
1935  *
1936  * Otherwise we leave the config alone, with all the vdevs in place in
1937  * the original pool.
1938  */
1939 static void
1940 spa_try_repair(spa_t *spa, nvlist_t *config)
1941 {
1942         uint_t extracted;
1943         uint64_t *glist;
1944         uint_t i, gcount;
1945         nvlist_t *nvl;
1946         vdev_t **vd;
1947         boolean_t attempt_reopen;
1948 
1949         if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_SPLIT, &nvl) != 0)
1950                 return;
1951 
1952         /* check that the config is complete */
1953         if (nvlist_lookup_uint64_array(nvl, ZPOOL_CONFIG_SPLIT_LIST,
1954             &glist, &gcount) != 0)
1955                 return;
1956 
1957         vd = kmem_zalloc(gcount * sizeof (vdev_t *), KM_SLEEP);
1958 
1959         /* attempt to online all the vdevs & validate */
1960         attempt_reopen = B_TRUE;
1961         for (i = 0; i < gcount; i++) {
1962                 if (glist[i] == 0)      /* vdev is hole */
1963                         continue;
1964 
1965                 vd[i] = spa_lookup_by_guid(spa, glist[i], B_FALSE);
1966                 if (vd[i] == NULL) {
1967                         /*
1968                          * Don't bother attempting to reopen the disks;
1969                          * just do the split.
1970                          */
1971                         attempt_reopen = B_FALSE;
1972                 } else {
1973                         /* attempt to re-online it */
1974                         vd[i]->vdev_offline = B_FALSE;
1975                 }
1976         }
1977 
1978         if (attempt_reopen) {
1979                 vdev_reopen(spa->spa_root_vdev);
1980 
1981                 /* check each device to see what state it's in */
1982                 for (extracted = 0, i = 0; i < gcount; i++) {
1983                         if (vd[i] != NULL &&
1984                             vd[i]->vdev_stat.vs_aux != VDEV_AUX_SPLIT_POOL)
1985                                 break;
1986                         ++extracted;
1987                 }
1988         }
1989 
1990         /*
1991          * If every disk has been moved to the new pool, or if we never
1992          * even attempted to look at them, then we split them off for
1993          * good.
1994          */
1995         if (!attempt_reopen || gcount == extracted) {
1996                 for (i = 0; i < gcount; i++)
1997                         if (vd[i] != NULL)
1998                                 vdev_split(vd[i]);
1999                 vdev_reopen(spa->spa_root_vdev);
2000         }
2001 
2002         kmem_free(vd, gcount * sizeof (vdev_t *));
2003 }
2004 
2005 static int
2006 spa_load(spa_t *spa, spa_load_state_t state, spa_import_type_t type,
2007     boolean_t mosconfig)
2008 {
2009         nvlist_t *config = spa->spa_config;
2010         char *ereport = FM_EREPORT_ZFS_POOL;
2011         char *comment;
2012         int error;
2013         uint64_t pool_guid;
2014         nvlist_t *nvl;
2015 
2016         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID, &pool_guid))
2017                 return (SET_ERROR(EINVAL));
2018 
2019         ASSERT(spa->spa_comment == NULL);
2020         if (nvlist_lookup_string(config, ZPOOL_CONFIG_COMMENT, &comment) == 0)
2021                 spa->spa_comment = spa_strdup(comment);
2022 
2023         /*
2024          * Versioning wasn't explicitly added to the label until later, so if
2025          * it's not present treat it as the initial version.
2026          */
2027         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_VERSION,
2028             &spa->spa_ubsync.ub_version) != 0)
2029                 spa->spa_ubsync.ub_version = SPA_VERSION_INITIAL;
2030 
2031         (void) nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
2032             &spa->spa_config_txg);
2033 
2034         if ((state == SPA_LOAD_IMPORT || state == SPA_LOAD_TRYIMPORT) &&
2035             spa_guid_exists(pool_guid, 0)) {
2036                 error = SET_ERROR(EEXIST);
2037         } else {
2038                 spa->spa_config_guid = pool_guid;
2039 
2040                 if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_SPLIT,
2041                     &nvl) == 0) {
2042                         VERIFY(nvlist_dup(nvl, &spa->spa_config_splitting,
2043                             KM_SLEEP) == 0);
2044                 }
2045 
2046                 nvlist_free(spa->spa_load_info);
2047                 spa->spa_load_info = fnvlist_alloc();
2048 
2049                 gethrestime(&spa->spa_loaded_ts);
2050                 error = spa_load_impl(spa, pool_guid, config, state, type,
2051                     mosconfig, &ereport);
2052         }
2053 
2054         spa->spa_minref = refcount_count(&spa->spa_refcount);
2055         if (error) {
2056                 if (error != EEXIST) {
2057                         spa->spa_loaded_ts.tv_sec = 0;
2058                         spa->spa_loaded_ts.tv_nsec = 0;
2059                 }
2060                 if (error != EBADF) {
2061                         zfs_ereport_post(ereport, spa, NULL, NULL, 0, 0);
2062                 }
2063         }
2064         spa->spa_load_state = error ? SPA_LOAD_ERROR : SPA_LOAD_NONE;
2065         spa->spa_ena = 0;
2066 
2067         return (error);
2068 }
2069 
2070 /*
2071  * Load an existing storage pool, using the pool's builtin spa_config as a
2072  * source of configuration information.
2073  */
2074 static int
2075 spa_load_impl(spa_t *spa, uint64_t pool_guid, nvlist_t *config,
2076     spa_load_state_t state, spa_import_type_t type, boolean_t mosconfig,
2077     char **ereport)
2078 {
2079         int error = 0;
2080         nvlist_t *nvroot = NULL;
2081         nvlist_t *label;
2082         vdev_t *rvd;
2083         uberblock_t *ub = &spa->spa_uberblock;
2084         uint64_t children, config_cache_txg = spa->spa_config_txg;
2085         int orig_mode = spa->spa_mode;
2086         int parse;
2087         uint64_t obj;
2088         boolean_t missing_feat_write = B_FALSE;
2089 
2090         /*
2091          * If this is an untrusted config, access the pool in read-only mode.
2092          * This prevents things like resilvering recently removed devices.
2093          */
2094         if (!mosconfig)
2095                 spa->spa_mode = FREAD;
2096 
2097         ASSERT(MUTEX_HELD(&spa_namespace_lock));
2098 
2099         spa->spa_load_state = state;
2100 
2101         if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nvroot))
2102                 return (SET_ERROR(EINVAL));
2103 
2104         parse = (type == SPA_IMPORT_EXISTING ?
2105             VDEV_ALLOC_LOAD : VDEV_ALLOC_SPLIT);
2106 
2107         /*
2108          * Create "The Godfather" zio to hold all async IOs
2109          */
2110         spa->spa_async_zio_root = zio_root(spa, NULL, NULL,
2111             ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_GODFATHER);
2112 
2113         /*
2114          * Parse the configuration into a vdev tree.  We explicitly set the
2115          * value that will be returned by spa_version() since parsing the
2116          * configuration requires knowing the version number.
2117          */
2118         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2119         error = spa_config_parse(spa, &rvd, nvroot, NULL, 0, parse);
2120         spa_config_exit(spa, SCL_ALL, FTAG);
2121 
2122         if (error != 0)
2123                 return (error);
2124 
2125         ASSERT(spa->spa_root_vdev == rvd);
2126 
2127         if (type != SPA_IMPORT_ASSEMBLE) {
2128                 ASSERT(spa_guid(spa) == pool_guid);
2129         }
2130 
2131         /*
2132          * Try to open all vdevs, loading each label in the process.
2133          */
2134         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2135         error = vdev_open(rvd);
2136         spa_config_exit(spa, SCL_ALL, FTAG);
2137         if (error != 0)
2138                 return (error);
2139 
2140         /*
2141          * We need to validate the vdev labels against the configuration that
2142          * we have in hand, which is dependent on the setting of mosconfig. If
2143          * mosconfig is true then we're validating the vdev labels based on
2144          * that config.  Otherwise, we're validating against the cached config
2145          * (zpool.cache) that was read when we loaded the zfs module, and then
2146          * later we will recursively call spa_load() and validate against
2147          * the vdev config.
2148          *
2149          * If we're assembling a new pool that's been split off from an
2150          * existing pool, the labels haven't yet been updated so we skip
2151          * validation for now.
2152          */
2153         if (type != SPA_IMPORT_ASSEMBLE) {
2154                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2155                 error = vdev_validate(rvd, mosconfig);
2156                 spa_config_exit(spa, SCL_ALL, FTAG);
2157 
2158                 if (error != 0)
2159                         return (error);
2160 
2161                 if (rvd->vdev_state <= VDEV_STATE_CANT_OPEN)
2162                         return (SET_ERROR(ENXIO));
2163         }
2164 
2165         /*
2166          * Find the best uberblock.
2167          */
2168         vdev_uberblock_load(rvd, ub, &label);
2169 
2170         /*
2171          * If we weren't able to find a single valid uberblock, return failure.
2172          */
2173         if (ub->ub_txg == 0) {
2174                 nvlist_free(label);
2175                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, ENXIO));
2176         }
2177 
2178         /*
2179          * If the pool has an unsupported version we can't open it.
2180          */
2181         if (!SPA_VERSION_IS_SUPPORTED(ub->ub_version)) {
2182                 nvlist_free(label);
2183                 return (spa_vdev_err(rvd, VDEV_AUX_VERSION_NEWER, ENOTSUP));
2184         }
2185 
2186         if (ub->ub_version >= SPA_VERSION_FEATURES) {
2187                 nvlist_t *features;
2188 
2189                 /*
2190                  * If we weren't able to find what's necessary for reading the
2191                  * MOS in the label, return failure.
2192                  */
2193                 if (label == NULL || nvlist_lookup_nvlist(label,
2194                     ZPOOL_CONFIG_FEATURES_FOR_READ, &features) != 0) {
2195                         nvlist_free(label);
2196                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA,
2197                             ENXIO));
2198                 }
2199 
2200                 /*
2201                  * Update our in-core representation with the definitive values
2202                  * from the label.
2203                  */
2204                 nvlist_free(spa->spa_label_features);
2205                 VERIFY(nvlist_dup(features, &spa->spa_label_features, 0) == 0);
2206         }
2207 
2208         nvlist_free(label);
2209 
2210         /*
2211          * Look through entries in the label nvlist's features_for_read. If
2212          * there is a feature listed there which we don't understand then we
2213          * cannot open a pool.
2214          */
2215         if (ub->ub_version >= SPA_VERSION_FEATURES) {
2216                 nvlist_t *unsup_feat;
2217 
2218                 VERIFY(nvlist_alloc(&unsup_feat, NV_UNIQUE_NAME, KM_SLEEP) ==
2219                     0);
2220 
2221                 for (nvpair_t *nvp = nvlist_next_nvpair(spa->spa_label_features,
2222                     NULL); nvp != NULL;
2223                     nvp = nvlist_next_nvpair(spa->spa_label_features, nvp)) {
2224                         if (!zfeature_is_supported(nvpair_name(nvp))) {
2225                                 VERIFY(nvlist_add_string(unsup_feat,
2226                                     nvpair_name(nvp), "") == 0);
2227                         }
2228                 }
2229 
2230                 if (!nvlist_empty(unsup_feat)) {
2231                         VERIFY(nvlist_add_nvlist(spa->spa_load_info,
2232                             ZPOOL_CONFIG_UNSUP_FEAT, unsup_feat) == 0);
2233                         nvlist_free(unsup_feat);
2234                         return (spa_vdev_err(rvd, VDEV_AUX_UNSUP_FEAT,
2235                             ENOTSUP));
2236                 }
2237 
2238                 nvlist_free(unsup_feat);
2239         }
2240 
2241         /*
2242          * If the vdev guid sum doesn't match the uberblock, we have an
2243          * incomplete configuration.  We first check to see if the pool
2244          * is aware of the complete config (i.e ZPOOL_CONFIG_VDEV_CHILDREN).
2245          * If it is, defer the vdev_guid_sum check till later so we
2246          * can handle missing vdevs.
2247          */
2248         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN,
2249             &children) != 0 && mosconfig && type != SPA_IMPORT_ASSEMBLE &&
2250             rvd->vdev_guid_sum != ub->ub_guid_sum)
2251                 return (spa_vdev_err(rvd, VDEV_AUX_BAD_GUID_SUM, ENXIO));
2252 
2253         if (type != SPA_IMPORT_ASSEMBLE && spa->spa_config_splitting) {
2254                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2255                 spa_try_repair(spa, config);
2256                 spa_config_exit(spa, SCL_ALL, FTAG);
2257                 nvlist_free(spa->spa_config_splitting);
2258                 spa->spa_config_splitting = NULL;
2259         }
2260 
2261         /*
2262          * Initialize internal SPA structures.
2263          */
2264         spa->spa_state = POOL_STATE_ACTIVE;
2265         spa->spa_ubsync = spa->spa_uberblock;
2266         spa->spa_verify_min_txg = spa->spa_extreme_rewind ?
2267             TXG_INITIAL - 1 : spa_last_synced_txg(spa) - TXG_DEFER_SIZE - 1;
2268         spa->spa_first_txg = spa->spa_last_ubsync_txg ?
2269             spa->spa_last_ubsync_txg : spa_last_synced_txg(spa) + 1;
2270         spa->spa_claim_max_txg = spa->spa_first_txg;
2271         spa->spa_prev_software_version = ub->ub_software_version;
2272 
2273         error = dsl_pool_init(spa, spa->spa_first_txg, &spa->spa_dsl_pool);
2274         if (error)
2275                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2276         spa->spa_meta_objset = spa->spa_dsl_pool->dp_meta_objset;
2277 
2278         if (spa_dir_prop(spa, DMU_POOL_CONFIG, &spa->spa_config_object) != 0)
2279                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2280 
2281         if (spa_version(spa) >= SPA_VERSION_FEATURES) {
2282                 boolean_t missing_feat_read = B_FALSE;
2283                 nvlist_t *unsup_feat, *enabled_feat;
2284 
2285                 if (spa_dir_prop(spa, DMU_POOL_FEATURES_FOR_READ,
2286                     &spa->spa_feat_for_read_obj) != 0) {
2287                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2288                 }
2289 
2290                 if (spa_dir_prop(spa, DMU_POOL_FEATURES_FOR_WRITE,
2291                     &spa->spa_feat_for_write_obj) != 0) {
2292                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2293                 }
2294 
2295                 if (spa_dir_prop(spa, DMU_POOL_FEATURE_DESCRIPTIONS,
2296                     &spa->spa_feat_desc_obj) != 0) {
2297                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2298                 }
2299 
2300                 enabled_feat = fnvlist_alloc();
2301                 unsup_feat = fnvlist_alloc();
2302 
2303                 if (!spa_features_check(spa, B_FALSE,
2304                     unsup_feat, enabled_feat))
2305                         missing_feat_read = B_TRUE;
2306 
2307                 if (spa_writeable(spa) || state == SPA_LOAD_TRYIMPORT) {
2308                         if (!spa_features_check(spa, B_TRUE,
2309                             unsup_feat, enabled_feat)) {
2310                                 missing_feat_write = B_TRUE;
2311                         }
2312                 }
2313 
2314                 fnvlist_add_nvlist(spa->spa_load_info,
2315                     ZPOOL_CONFIG_ENABLED_FEAT, enabled_feat);
2316 
2317                 if (!nvlist_empty(unsup_feat)) {
2318                         fnvlist_add_nvlist(spa->spa_load_info,
2319                             ZPOOL_CONFIG_UNSUP_FEAT, unsup_feat);
2320                 }
2321 
2322                 fnvlist_free(enabled_feat);
2323                 fnvlist_free(unsup_feat);
2324 
2325                 if (!missing_feat_read) {
2326                         fnvlist_add_boolean(spa->spa_load_info,
2327                             ZPOOL_CONFIG_CAN_RDONLY);
2328                 }
2329 
2330                 /*
2331                  * If the state is SPA_LOAD_TRYIMPORT, our objective is
2332                  * twofold: to determine whether the pool is available for
2333                  * import in read-write mode and (if it is not) whether the
2334                  * pool is available for import in read-only mode. If the pool
2335                  * is available for import in read-write mode, it is displayed
2336                  * as available in userland; if it is not available for import
2337                  * in read-only mode, it is displayed as unavailable in
2338                  * userland. If the pool is available for import in read-only
2339                  * mode but not read-write mode, it is displayed as unavailable
2340                  * in userland with a special note that the pool is actually
2341                  * available for open in read-only mode.
2342                  *
2343                  * As a result, if the state is SPA_LOAD_TRYIMPORT and we are
2344                  * missing a feature for write, we must first determine whether
2345                  * the pool can be opened read-only before returning to
2346                  * userland in order to know whether to display the
2347                  * abovementioned note.
2348                  */
2349                 if (missing_feat_read || (missing_feat_write &&
2350                     spa_writeable(spa))) {
2351                         return (spa_vdev_err(rvd, VDEV_AUX_UNSUP_FEAT,
2352                             ENOTSUP));
2353                 }
2354 
2355                 /*
2356                  * Load refcounts for ZFS features from disk into an in-memory
2357                  * cache during SPA initialization.
2358                  */
2359                 for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
2360                         uint64_t refcount;
2361 
2362                         error = feature_get_refcount_from_disk(spa,
2363                             &spa_feature_table[i], &refcount);
2364                         if (error == 0) {
2365                                 spa->spa_feat_refcount_cache[i] = refcount;
2366                         } else if (error == ENOTSUP) {
2367                                 spa->spa_feat_refcount_cache[i] =
2368                                     SPA_FEATURE_DISABLED;
2369                         } else {
2370                                 return (spa_vdev_err(rvd,
2371                                     VDEV_AUX_CORRUPT_DATA, EIO));
2372                         }
2373                 }
2374         }
2375 
2376         if (spa_feature_is_active(spa, SPA_FEATURE_ENABLED_TXG)) {
2377                 if (spa_dir_prop(spa, DMU_POOL_FEATURE_ENABLED_TXG,
2378                     &spa->spa_feat_enabled_txg_obj) != 0) {
2379                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2380                 }
2381         }
2382 
2383         spa->spa_is_initializing = B_TRUE;
2384         error = dsl_pool_open(spa->spa_dsl_pool);
2385         spa->spa_is_initializing = B_FALSE;
2386         if (error != 0)
2387                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2388 
2389         if (!mosconfig) {
2390                 uint64_t hostid;
2391                 nvlist_t *policy = NULL, *nvconfig;
2392 
2393                 if (load_nvlist(spa, spa->spa_config_object, &nvconfig) != 0)
2394                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2395 
2396                 if (!spa_is_root(spa) && nvlist_lookup_uint64(nvconfig,
2397                     ZPOOL_CONFIG_HOSTID, &hostid) == 0) {
2398                         char *hostname;
2399                         unsigned long myhostid = 0;
2400 
2401                         VERIFY(nvlist_lookup_string(nvconfig,
2402                             ZPOOL_CONFIG_HOSTNAME, &hostname) == 0);
2403 
2404 #ifdef  _KERNEL
2405                         myhostid = zone_get_hostid(NULL);
2406 #else   /* _KERNEL */
2407                         /*
2408                          * We're emulating the system's hostid in userland, so
2409                          * we can't use zone_get_hostid().
2410                          */
2411                         (void) ddi_strtoul(hw_serial, NULL, 10, &myhostid);
2412 #endif  /* _KERNEL */
2413                         if (hostid != 0 && myhostid != 0 &&
2414                             hostid != myhostid) {
2415                                 nvlist_free(nvconfig);
2416                                 cmn_err(CE_WARN, "pool '%s' could not be "
2417                                     "loaded as it was last accessed by "
2418                                     "another system (host: %s hostid: 0x%lx). "
2419                                     "See: http://illumos.org/msg/ZFS-8000-EY",
2420                                     spa_name(spa), hostname,
2421                                     (unsigned long)hostid);
2422                                 return (SET_ERROR(EBADF));
2423                         }
2424                 }
2425                 if (nvlist_lookup_nvlist(spa->spa_config,
2426                     ZPOOL_REWIND_POLICY, &policy) == 0)
2427                         VERIFY(nvlist_add_nvlist(nvconfig,
2428                             ZPOOL_REWIND_POLICY, policy) == 0);
2429 
2430                 spa_config_set(spa, nvconfig);
2431                 spa_unload(spa);
2432                 spa_deactivate(spa);
2433                 spa_activate(spa, orig_mode);
2434 
2435                 return (spa_load(spa, state, SPA_IMPORT_EXISTING, B_TRUE));
2436         }
2437 
2438         if (spa_dir_prop(spa, DMU_POOL_SYNC_BPOBJ, &obj) != 0)
2439                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2440         error = bpobj_open(&spa->spa_deferred_bpobj, spa->spa_meta_objset, obj);
2441         if (error != 0)
2442                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2443 
2444         /*
2445          * Load the bit that tells us to use the new accounting function
2446          * (raid-z deflation).  If we have an older pool, this will not
2447          * be present.
2448          */
2449         error = spa_dir_prop(spa, DMU_POOL_DEFLATE, &spa->spa_deflate);
2450         if (error != 0 && error != ENOENT)
2451                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2452 
2453         error = spa_dir_prop(spa, DMU_POOL_CREATION_VERSION,
2454             &spa->spa_creation_version);
2455         if (error != 0 && error != ENOENT)
2456                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2457 
2458         /*
2459          * Load the persistent error log.  If we have an older pool, this will
2460          * not be present.
2461          */
2462         error = spa_dir_prop(spa, DMU_POOL_ERRLOG_LAST, &spa->spa_errlog_last);
2463         if (error != 0 && error != ENOENT)
2464                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2465 
2466         error = spa_dir_prop(spa, DMU_POOL_ERRLOG_SCRUB,
2467             &spa->spa_errlog_scrub);
2468         if (error != 0 && error != ENOENT)
2469                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2470 
2471         /*
2472          * Load the history object.  If we have an older pool, this
2473          * will not be present.
2474          */
2475         error = spa_dir_prop(spa, DMU_POOL_HISTORY, &spa->spa_history);
2476         if (error != 0 && error != ENOENT)
2477                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2478 
2479         /*
2480          * If we're assembling the pool from the split-off vdevs of
2481          * an existing pool, we don't want to attach the spares & cache
2482          * devices.
2483          */
2484 
2485         /*
2486          * Load any hot spares for this pool.
2487          */
2488         error = spa_dir_prop(spa, DMU_POOL_SPARES, &spa->spa_spares.sav_object);
2489         if (error != 0 && error != ENOENT)
2490                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2491         if (error == 0 && type != SPA_IMPORT_ASSEMBLE) {
2492                 ASSERT(spa_version(spa) >= SPA_VERSION_SPARES);
2493                 if (load_nvlist(spa, spa->spa_spares.sav_object,
2494                     &spa->spa_spares.sav_config) != 0)
2495                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2496 
2497                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2498                 spa_load_spares(spa);
2499                 spa_config_exit(spa, SCL_ALL, FTAG);
2500         } else if (error == 0) {
2501                 spa->spa_spares.sav_sync = B_TRUE;
2502         }
2503 
2504         /*
2505          * Load any level 2 ARC devices for this pool.
2506          */
2507         error = spa_dir_prop(spa, DMU_POOL_L2CACHE,
2508             &spa->spa_l2cache.sav_object);
2509         if (error != 0 && error != ENOENT)
2510                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2511         if (error == 0 && type != SPA_IMPORT_ASSEMBLE) {
2512                 ASSERT(spa_version(spa) >= SPA_VERSION_L2CACHE);
2513                 if (load_nvlist(spa, spa->spa_l2cache.sav_object,
2514                     &spa->spa_l2cache.sav_config) != 0)
2515                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2516 
2517                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2518                 spa_load_l2cache(spa);
2519                 spa_config_exit(spa, SCL_ALL, FTAG);
2520         } else if (error == 0) {
2521                 spa->spa_l2cache.sav_sync = B_TRUE;
2522         }
2523 
2524         spa->spa_delegation = zpool_prop_default_numeric(ZPOOL_PROP_DELEGATION);
2525 
2526         error = spa_dir_prop(spa, DMU_POOL_PROPS, &spa->spa_pool_props_object);
2527         if (error && error != ENOENT)
2528                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2529 
2530         if (error == 0) {
2531                 uint64_t autoreplace;
2532 
2533                 spa_prop_find(spa, ZPOOL_PROP_BOOTFS, &spa->spa_bootfs);
2534                 spa_prop_find(spa, ZPOOL_PROP_AUTOREPLACE, &autoreplace);
2535                 spa_prop_find(spa, ZPOOL_PROP_DELEGATION, &spa->spa_delegation);
2536                 spa_prop_find(spa, ZPOOL_PROP_FAILUREMODE, &spa->spa_failmode);
2537                 spa_prop_find(spa, ZPOOL_PROP_AUTOEXPAND, &spa->spa_autoexpand);
2538                 spa_prop_find(spa, ZPOOL_PROP_DEDUPDITTO,
2539                     &spa->spa_dedup_ditto);
2540 
2541                 spa->spa_autoreplace = (autoreplace != 0);
2542         }
2543 
2544         /*
2545          * If the 'autoreplace' property is set, then post a resource notifying
2546          * the ZFS DE that it should not issue any faults for unopenable
2547          * devices.  We also iterate over the vdevs, and post a sysevent for any
2548          * unopenable vdevs so that the normal autoreplace handler can take
2549          * over.
2550          */
2551         if (spa->spa_autoreplace && state != SPA_LOAD_TRYIMPORT) {
2552                 spa_check_removed(spa->spa_root_vdev);
2553                 /*
2554                  * For the import case, this is done in spa_import(), because
2555                  * at this point we're using the spare definitions from
2556                  * the MOS config, not necessarily from the userland config.
2557                  */
2558                 if (state != SPA_LOAD_IMPORT) {
2559                         spa_aux_check_removed(&spa->spa_spares);
2560                         spa_aux_check_removed(&spa->spa_l2cache);
2561                 }
2562         }
2563 
2564         /*
2565          * Load the vdev state for all toplevel vdevs.
2566          */
2567         vdev_load(rvd);
2568 
2569         /*
2570          * Propagate the leaf DTLs we just loaded all the way up the tree.
2571          */
2572         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2573         vdev_dtl_reassess(rvd, 0, 0, B_FALSE);
2574         spa_config_exit(spa, SCL_ALL, FTAG);
2575 
2576         /*
2577          * Load the DDTs (dedup tables).
2578          */
2579         error = ddt_load(spa);
2580         if (error != 0)
2581                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2582 
2583         spa_update_dspace(spa);
2584 
2585         /*
2586          * Validate the config, using the MOS config to fill in any
2587          * information which might be missing.  If we fail to validate
2588          * the config then declare the pool unfit for use. If we're
2589          * assembling a pool from a split, the log is not transferred
2590          * over.
2591          */
2592         if (type != SPA_IMPORT_ASSEMBLE) {
2593                 nvlist_t *nvconfig;
2594 
2595                 if (load_nvlist(spa, spa->spa_config_object, &nvconfig) != 0)
2596                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2597 
2598                 if (!spa_config_valid(spa, nvconfig)) {
2599                         nvlist_free(nvconfig);
2600                         return (spa_vdev_err(rvd, VDEV_AUX_BAD_GUID_SUM,
2601                             ENXIO));
2602                 }
2603                 nvlist_free(nvconfig);
2604 
2605                 /*
2606                  * Now that we've validated the config, check the state of the
2607                  * root vdev.  If it can't be opened, it indicates one or
2608                  * more toplevel vdevs are faulted.
2609                  */
2610                 if (rvd->vdev_state <= VDEV_STATE_CANT_OPEN)
2611                         return (SET_ERROR(ENXIO));
2612 
2613                 if (spa_check_logs(spa)) {
2614                         *ereport = FM_EREPORT_ZFS_LOG_REPLAY;
2615                         return (spa_vdev_err(rvd, VDEV_AUX_BAD_LOG, ENXIO));
2616                 }
2617         }
2618 
2619         if (missing_feat_write) {
2620                 ASSERT(state == SPA_LOAD_TRYIMPORT);
2621 
2622                 /*
2623                  * At this point, we know that we can open the pool in
2624                  * read-only mode but not read-write mode. We now have enough
2625                  * information and can return to userland.
2626                  */
2627                 return (spa_vdev_err(rvd, VDEV_AUX_UNSUP_FEAT, ENOTSUP));
2628         }
2629 
2630         /*
2631          * We've successfully opened the pool, verify that we're ready
2632          * to start pushing transactions.
2633          */
2634         if (state != SPA_LOAD_TRYIMPORT) {
2635                 if (error = spa_load_verify(spa))
2636                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA,
2637                             error));
2638         }
2639 
2640         if (spa_writeable(spa) && (state == SPA_LOAD_RECOVER ||
2641             spa->spa_load_max_txg == UINT64_MAX)) {
2642                 dmu_tx_t *tx;
2643                 int need_update = B_FALSE;
2644 
2645                 ASSERT(state != SPA_LOAD_TRYIMPORT);
2646 
2647                 /*
2648                  * Claim log blocks that haven't been committed yet.
2649                  * This must all happen in a single txg.
2650                  * Note: spa_claim_max_txg is updated by spa_claim_notify(),
2651                  * invoked from zil_claim_log_block()'s i/o done callback.
2652                  * Price of rollback is that we abandon the log.
2653                  */
2654                 spa->spa_claiming = B_TRUE;
2655 
2656                 tx = dmu_tx_create_assigned(spa_get_dsl(spa),
2657                     spa_first_txg(spa));
2658                 (void) dmu_objset_find(spa_name(spa),
2659                     zil_claim, tx, DS_FIND_CHILDREN);
2660                 dmu_tx_commit(tx);
2661 
2662                 spa->spa_claiming = B_FALSE;
2663 
2664                 spa_set_log_state(spa, SPA_LOG_GOOD);
2665                 spa->spa_sync_on = B_TRUE;
2666                 txg_sync_start(spa->spa_dsl_pool);
2667 
2668                 /*
2669                  * Wait for all claims to sync.  We sync up to the highest
2670                  * claimed log block birth time so that claimed log blocks
2671                  * don't appear to be from the future.  spa_claim_max_txg
2672                  * will have been set for us by either zil_check_log_chain()
2673                  * (invoked from spa_check_logs()) or zil_claim() above.
2674                  */
2675                 txg_wait_synced(spa->spa_dsl_pool, spa->spa_claim_max_txg);
2676 
2677                 /*
2678                  * If the config cache is stale, or we have uninitialized
2679                  * metaslabs (see spa_vdev_add()), then update the config.
2680                  *
2681                  * If this is a verbatim import, trust the current
2682                  * in-core spa_config and update the disk labels.
2683                  */
2684                 if (config_cache_txg != spa->spa_config_txg ||
2685                     state == SPA_LOAD_IMPORT ||
2686                     state == SPA_LOAD_RECOVER ||
2687                     (spa->spa_import_flags & ZFS_IMPORT_VERBATIM))
2688                         need_update = B_TRUE;
2689 
2690                 for (int c = 0; c < rvd->vdev_children; c++)
2691                         if (rvd->vdev_child[c]->vdev_ms_array == 0)
2692                                 need_update = B_TRUE;
2693 
2694                 /*
2695                  * Update the config cache asychronously in case we're the
2696                  * root pool, in which case the config cache isn't writable yet.
2697                  */
2698                 if (need_update)
2699                         spa_async_request(spa, SPA_ASYNC_CONFIG_UPDATE);
2700 
2701                 /*
2702                  * Check all DTLs to see if anything needs resilvering.
2703                  */
2704                 if (!dsl_scan_resilvering(spa->spa_dsl_pool) &&
2705                     vdev_resilver_needed(rvd, NULL, NULL))
2706                         spa_async_request(spa, SPA_ASYNC_RESILVER);
2707 
2708                 /*
2709                  * Log the fact that we booted up (so that we can detect if
2710                  * we rebooted in the middle of an operation).
2711                  */
2712                 spa_history_log_version(spa, "open");
2713 
2714                 /*
2715                  * Delete any inconsistent datasets.
2716                  */
2717                 (void) dmu_objset_find(spa_name(spa),
2718                     dsl_destroy_inconsistent, NULL, DS_FIND_CHILDREN);
2719 
2720                 /*
2721                  * Clean up any stale temporary dataset userrefs.
2722                  */
2723                 dsl_pool_clean_tmp_userrefs(spa->spa_dsl_pool);
2724         }
2725 
2726         return (0);
2727 }
2728 
2729 static int
2730 spa_load_retry(spa_t *spa, spa_load_state_t state, int mosconfig)
2731 {
2732         int mode = spa->spa_mode;
2733 
2734         spa_unload(spa);
2735         spa_deactivate(spa);
2736 
2737         spa->spa_load_max_txg--;
2738 
2739         spa_activate(spa, mode);
2740         spa_async_suspend(spa);
2741 
2742         return (spa_load(spa, state, SPA_IMPORT_EXISTING, mosconfig));
2743 }
2744 
2745 /*
2746  * If spa_load() fails this function will try loading prior txg's. If
2747  * 'state' is SPA_LOAD_RECOVER and one of these loads succeeds the pool
2748  * will be rewound to that txg. If 'state' is not SPA_LOAD_RECOVER this
2749  * function will not rewind the pool and will return the same error as
2750  * spa_load().
2751  */
2752 static int
2753 spa_load_best(spa_t *spa, spa_load_state_t state, int mosconfig,
2754     uint64_t max_request, int rewind_flags)
2755 {
2756         nvlist_t *loadinfo = NULL;
2757         nvlist_t *config = NULL;
2758         int load_error, rewind_error;
2759         uint64_t safe_rewind_txg;
2760         uint64_t min_txg;
2761 
2762         if (spa->spa_load_txg && state == SPA_LOAD_RECOVER) {
2763                 spa->spa_load_max_txg = spa->spa_load_txg;
2764                 spa_set_log_state(spa, SPA_LOG_CLEAR);
2765         } else {
2766                 spa->spa_load_max_txg = max_request;
2767         }
2768 
2769         load_error = rewind_error = spa_load(spa, state, SPA_IMPORT_EXISTING,
2770             mosconfig);
2771         if (load_error == 0)
2772                 return (0);
2773 
2774         if (spa->spa_root_vdev != NULL)
2775                 config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
2776 
2777         spa->spa_last_ubsync_txg = spa->spa_uberblock.ub_txg;
2778         spa->spa_last_ubsync_txg_ts = spa->spa_uberblock.ub_timestamp;
2779 
2780         if (rewind_flags & ZPOOL_NEVER_REWIND) {
2781                 nvlist_free(config);
2782                 return (load_error);
2783         }
2784 
2785         if (state == SPA_LOAD_RECOVER) {
2786                 /* Price of rolling back is discarding txgs, including log */
2787                 spa_set_log_state(spa, SPA_LOG_CLEAR);
2788         } else {
2789                 /*
2790                  * If we aren't rolling back save the load info from our first
2791                  * import attempt so that we can restore it after attempting
2792                  * to rewind.
2793                  */
2794                 loadinfo = spa->spa_load_info;
2795                 spa->spa_load_info = fnvlist_alloc();
2796         }
2797 
2798         spa->spa_load_max_txg = spa->spa_last_ubsync_txg;
2799         safe_rewind_txg = spa->spa_last_ubsync_txg - TXG_DEFER_SIZE;
2800         min_txg = (rewind_flags & ZPOOL_EXTREME_REWIND) ?
2801             TXG_INITIAL : safe_rewind_txg;
2802 
2803         /*
2804          * Continue as long as we're finding errors, we're still within
2805          * the acceptable rewind range, and we're still finding uberblocks
2806          */
2807         while (rewind_error && spa->spa_uberblock.ub_txg >= min_txg &&
2808             spa->spa_uberblock.ub_txg <= spa->spa_load_max_txg) {
2809                 if (spa->spa_load_max_txg < safe_rewind_txg)
2810                         spa->spa_extreme_rewind = B_TRUE;
2811                 rewind_error = spa_load_retry(spa, state, mosconfig);
2812         }
2813 
2814         spa->spa_extreme_rewind = B_FALSE;
2815         spa->spa_load_max_txg = UINT64_MAX;
2816 
2817         if (config && (rewind_error || state != SPA_LOAD_RECOVER))
2818                 spa_config_set(spa, config);
2819 
2820         if (state == SPA_LOAD_RECOVER) {
2821                 ASSERT3P(loadinfo, ==, NULL);
2822                 return (rewind_error);
2823         } else {
2824                 /* Store the rewind info as part of the initial load info */
2825                 fnvlist_add_nvlist(loadinfo, ZPOOL_CONFIG_REWIND_INFO,
2826                     spa->spa_load_info);
2827 
2828                 /* Restore the initial load info */
2829                 fnvlist_free(spa->spa_load_info);
2830                 spa->spa_load_info = loadinfo;
2831 
2832                 return (load_error);
2833         }
2834 }
2835 
2836 /*
2837  * Pool Open/Import
2838  *
2839  * The import case is identical to an open except that the configuration is sent
2840  * down from userland, instead of grabbed from the configuration cache.  For the
2841  * case of an open, the pool configuration will exist in the
2842  * POOL_STATE_UNINITIALIZED state.
2843  *
2844  * The stats information (gen/count/ustats) is used to gather vdev statistics at
2845  * the same time open the pool, without having to keep around the spa_t in some
2846  * ambiguous state.
2847  */
2848 static int
2849 spa_open_common(const char *pool, spa_t **spapp, void *tag, nvlist_t *nvpolicy,
2850     nvlist_t **config)
2851 {
2852         spa_t *spa;
2853         spa_load_state_t state = SPA_LOAD_OPEN;
2854         int error;
2855         int locked = B_FALSE;
2856 
2857         *spapp = NULL;
2858 
2859         /*
2860          * As disgusting as this is, we need to support recursive calls to this
2861          * function because dsl_dir_open() is called during spa_load(), and ends
2862          * up calling spa_open() again.  The real fix is to figure out how to
2863          * avoid dsl_dir_open() calling this in the first place.
2864          */
2865         if (mutex_owner(&spa_namespace_lock) != curthread) {
2866                 mutex_enter(&spa_namespace_lock);
2867                 locked = B_TRUE;
2868         }
2869 
2870         if ((spa = spa_lookup(pool)) == NULL) {
2871                 if (locked)
2872                         mutex_exit(&spa_namespace_lock);
2873                 return (SET_ERROR(ENOENT));
2874         }
2875 
2876         if (spa->spa_state == POOL_STATE_UNINITIALIZED) {
2877                 zpool_rewind_policy_t policy;
2878 
2879                 zpool_get_rewind_policy(nvpolicy ? nvpolicy : spa->spa_config,
2880                     &policy);
2881                 if (policy.zrp_request & ZPOOL_DO_REWIND)
2882                         state = SPA_LOAD_RECOVER;
2883 
2884                 spa_activate(spa, spa_mode_global);
2885 
2886                 if (state != SPA_LOAD_RECOVER)
2887                         spa->spa_last_ubsync_txg = spa->spa_load_txg = 0;
2888 
2889                 error = spa_load_best(spa, state, B_FALSE, policy.zrp_txg,
2890                     policy.zrp_request);
2891 
2892                 if (error == EBADF) {
2893                         /*
2894                          * If vdev_validate() returns failure (indicated by
2895                          * EBADF), it indicates that one of the vdevs indicates
2896                          * that the pool has been exported or destroyed.  If
2897                          * this is the case, the config cache is out of sync and
2898                          * we should remove the pool from the namespace.
2899                          */
2900                         spa_unload(spa);
2901                         spa_deactivate(spa);
2902                         spa_config_sync(spa, B_TRUE, B_TRUE);
2903                         spa_remove(spa);
2904                         if (locked)
2905                                 mutex_exit(&spa_namespace_lock);
2906                         return (SET_ERROR(ENOENT));
2907                 }
2908 
2909                 if (error) {
2910                         /*
2911                          * We can't open the pool, but we still have useful
2912                          * information: the state of each vdev after the
2913                          * attempted vdev_open().  Return this to the user.
2914                          */
2915                         if (config != NULL && spa->spa_config) {
2916                                 VERIFY(nvlist_dup(spa->spa_config, config,
2917                                     KM_SLEEP) == 0);
2918                                 VERIFY(nvlist_add_nvlist(*config,
2919                                     ZPOOL_CONFIG_LOAD_INFO,
2920                                     spa->spa_load_info) == 0);
2921                         }
2922                         spa_unload(spa);
2923                         spa_deactivate(spa);
2924                         spa->spa_last_open_failed = error;
2925                         if (locked)
2926                                 mutex_exit(&spa_namespace_lock);
2927                         *spapp = NULL;
2928                         return (error);
2929                 }
2930         }
2931 
2932         spa_open_ref(spa, tag);
2933 
2934         if (config != NULL)
2935                 *config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
2936 
2937         /*
2938          * If we've recovered the pool, pass back any information we
2939          * gathered while doing the load.
2940          */
2941         if (state == SPA_LOAD_RECOVER) {
2942                 VERIFY(nvlist_add_nvlist(*config, ZPOOL_CONFIG_LOAD_INFO,
2943                     spa->spa_load_info) == 0);
2944         }
2945 
2946         if (locked) {
2947                 spa->spa_last_open_failed = 0;
2948                 spa->spa_last_ubsync_txg = 0;
2949                 spa->spa_load_txg = 0;
2950                 mutex_exit(&spa_namespace_lock);
2951         }
2952 
2953         *spapp = spa;
2954 
2955         return (0);
2956 }
2957 
2958 int
2959 spa_open_rewind(const char *name, spa_t **spapp, void *tag, nvlist_t *policy,
2960     nvlist_t **config)
2961 {
2962         return (spa_open_common(name, spapp, tag, policy, config));
2963 }
2964 
2965 int
2966 spa_open(const char *name, spa_t **spapp, void *tag)
2967 {
2968         return (spa_open_common(name, spapp, tag, NULL, NULL));
2969 }
2970 
2971 /*
2972  * Lookup the given spa_t, incrementing the inject count in the process,
2973  * preventing it from being exported or destroyed.
2974  */
2975 spa_t *
2976 spa_inject_addref(char *name)
2977 {
2978         spa_t *spa;
2979 
2980         mutex_enter(&spa_namespace_lock);
2981         if ((spa = spa_lookup(name)) == NULL) {
2982                 mutex_exit(&spa_namespace_lock);
2983                 return (NULL);
2984         }
2985         spa->spa_inject_ref++;
2986         mutex_exit(&spa_namespace_lock);
2987 
2988         return (spa);
2989 }
2990 
2991 void
2992 spa_inject_delref(spa_t *spa)
2993 {
2994         mutex_enter(&spa_namespace_lock);
2995         spa->spa_inject_ref--;
2996         mutex_exit(&spa_namespace_lock);
2997 }
2998 
2999 /*
3000  * Add spares device information to the nvlist.
3001  */
3002 static void
3003 spa_add_spares(spa_t *spa, nvlist_t *config)
3004 {
3005         nvlist_t **spares;
3006         uint_t i, nspares;
3007         nvlist_t *nvroot;
3008         uint64_t guid;
3009         vdev_stat_t *vs;
3010         uint_t vsc;
3011         uint64_t pool;
3012 
3013         ASSERT(spa_config_held(spa, SCL_CONFIG, RW_READER));
3014 
3015         if (spa->spa_spares.sav_count == 0)
3016                 return;
3017 
3018         VERIFY(nvlist_lookup_nvlist(config,
3019             ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
3020         VERIFY(nvlist_lookup_nvlist_array(spa->spa_spares.sav_config,
3021             ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0);
3022         if (nspares != 0) {
3023                 VERIFY(nvlist_add_nvlist_array(nvroot,
3024                     ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
3025                 VERIFY(nvlist_lookup_nvlist_array(nvroot,
3026                     ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0);
3027 
3028                 /*
3029                  * Go through and find any spares which have since been
3030                  * repurposed as an active spare.  If this is the case, update
3031                  * their status appropriately.
3032                  */
3033                 for (i = 0; i < nspares; i++) {
3034                         VERIFY(nvlist_lookup_uint64(spares[i],
3035                             ZPOOL_CONFIG_GUID, &guid) == 0);
3036                         if (spa_spare_exists(guid, &pool, NULL) &&
3037                             pool != 0ULL) {
3038                                 VERIFY(nvlist_lookup_uint64_array(
3039                                     spares[i], ZPOOL_CONFIG_VDEV_STATS,
3040                                     (uint64_t **)&vs, &vsc) == 0);
3041                                 vs->vs_state = VDEV_STATE_CANT_OPEN;
3042                                 vs->vs_aux = VDEV_AUX_SPARED;
3043                         }
3044                 }
3045         }
3046 }
3047 
3048 /*
3049  * Add l2cache device information to the nvlist, including vdev stats.
3050  */
3051 static void
3052 spa_add_l2cache(spa_t *spa, nvlist_t *config)
3053 {
3054         nvlist_t **l2cache;
3055         uint_t i, j, nl2cache;
3056         nvlist_t *nvroot;
3057         uint64_t guid;
3058         vdev_t *vd;
3059         vdev_stat_t *vs;
3060         uint_t vsc;
3061 
3062         ASSERT(spa_config_held(spa, SCL_CONFIG, RW_READER));
3063 
3064         if (spa->spa_l2cache.sav_count == 0)
3065                 return;
3066 
3067         VERIFY(nvlist_lookup_nvlist(config,
3068             ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
3069         VERIFY(nvlist_lookup_nvlist_array(spa->spa_l2cache.sav_config,
3070             ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0);
3071         if (nl2cache != 0) {
3072                 VERIFY(nvlist_add_nvlist_array(nvroot,
3073                     ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
3074                 VERIFY(nvlist_lookup_nvlist_array(nvroot,
3075                     ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0);
3076 
3077                 /*
3078                  * Update level 2 cache device stats.
3079                  */
3080 
3081                 for (i = 0; i < nl2cache; i++) {
3082                         VERIFY(nvlist_lookup_uint64(l2cache[i],
3083                             ZPOOL_CONFIG_GUID, &guid) == 0);
3084 
3085                         vd = NULL;
3086                         for (j = 0; j < spa->spa_l2cache.sav_count; j++) {
3087                                 if (guid ==
3088                                     spa->spa_l2cache.sav_vdevs[j]->vdev_guid) {
3089                                         vd = spa->spa_l2cache.sav_vdevs[j];
3090                                         break;
3091                                 }
3092                         }
3093                         ASSERT(vd != NULL);
3094 
3095                         VERIFY(nvlist_lookup_uint64_array(l2cache[i],
3096                             ZPOOL_CONFIG_VDEV_STATS, (uint64_t **)&vs, &vsc)
3097                             == 0);
3098                         vdev_get_stats(vd, vs);
3099                 }
3100         }
3101 }
3102 
3103 static void
3104 spa_add_feature_stats(spa_t *spa, nvlist_t *config)
3105 {
3106         nvlist_t *features;
3107         zap_cursor_t zc;
3108         zap_attribute_t za;
3109 
3110         ASSERT(spa_config_held(spa, SCL_CONFIG, RW_READER));
3111         VERIFY(nvlist_alloc(&features, NV_UNIQUE_NAME, KM_SLEEP) == 0);
3112 
3113         if (spa->spa_feat_for_read_obj != 0) {
3114                 for (zap_cursor_init(&zc, spa->spa_meta_objset,
3115                     spa->spa_feat_for_read_obj);
3116                     zap_cursor_retrieve(&zc, &za) == 0;
3117                     zap_cursor_advance(&zc)) {
3118                         ASSERT(za.za_integer_length == sizeof (uint64_t) &&
3119                             za.za_num_integers == 1);
3120                         VERIFY3U(0, ==, nvlist_add_uint64(features, za.za_name,
3121                             za.za_first_integer));
3122                 }
3123                 zap_cursor_fini(&zc);
3124         }
3125 
3126         if (spa->spa_feat_for_write_obj != 0) {
3127                 for (zap_cursor_init(&zc, spa->spa_meta_objset,
3128                     spa->spa_feat_for_write_obj);
3129                     zap_cursor_retrieve(&zc, &za) == 0;
3130                     zap_cursor_advance(&zc)) {
3131                         ASSERT(za.za_integer_length == sizeof (uint64_t) &&
3132                             za.za_num_integers == 1);
3133                         VERIFY3U(0, ==, nvlist_add_uint64(features, za.za_name,
3134                             za.za_first_integer));
3135                 }
3136                 zap_cursor_fini(&zc);
3137         }
3138 
3139         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_FEATURE_STATS,
3140             features) == 0);
3141         nvlist_free(features);
3142 }
3143 
3144 int
3145 spa_get_stats(const char *name, nvlist_t **config,
3146     char *altroot, size_t buflen)
3147 {
3148         int error;
3149         spa_t *spa;
3150 
3151         *config = NULL;
3152         error = spa_open_common(name, &spa, FTAG, NULL, config);
3153 
3154         if (spa != NULL) {
3155                 /*
3156                  * This still leaves a window of inconsistency where the spares
3157                  * or l2cache devices could change and the config would be
3158                  * self-inconsistent.
3159                  */
3160                 spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
3161 
3162                 if (*config != NULL) {
3163                         uint64_t loadtimes[2];
3164 
3165                         loadtimes[0] = spa->spa_loaded_ts.tv_sec;
3166                         loadtimes[1] = spa->spa_loaded_ts.tv_nsec;
3167                         VERIFY(nvlist_add_uint64_array(*config,
3168                             ZPOOL_CONFIG_LOADED_TIME, loadtimes, 2) == 0);
3169 
3170                         VERIFY(nvlist_add_uint64(*config,
3171                             ZPOOL_CONFIG_ERRCOUNT,
3172                             spa_get_errlog_size(spa)) == 0);
3173 
3174                         if (spa_suspended(spa))
3175                                 VERIFY(nvlist_add_uint64(*config,
3176                                     ZPOOL_CONFIG_SUSPENDED,
3177                                     spa->spa_failmode) == 0);
3178 
3179                         spa_add_spares(spa, *config);
3180                         spa_add_l2cache(spa, *config);
3181                         spa_add_feature_stats(spa, *config);
3182                 }
3183         }
3184 
3185         /*
3186          * We want to get the alternate root even for faulted pools, so we cheat
3187          * and call spa_lookup() directly.
3188          */
3189         if (altroot) {
3190                 if (spa == NULL) {
3191                         mutex_enter(&spa_namespace_lock);
3192                         spa = spa_lookup(name);
3193                         if (spa)
3194                                 spa_altroot(spa, altroot, buflen);
3195                         else
3196                                 altroot[0] = '\0';
3197                         spa = NULL;
3198                         mutex_exit(&spa_namespace_lock);
3199                 } else {
3200                         spa_altroot(spa, altroot, buflen);
3201                 }
3202         }
3203 
3204         if (spa != NULL) {
3205                 spa_config_exit(spa, SCL_CONFIG, FTAG);
3206                 spa_close(spa, FTAG);
3207         }
3208 
3209         return (error);
3210 }
3211 
3212 /*
3213  * Validate that the auxiliary device array is well formed.  We must have an
3214  * array of nvlists, each which describes a valid leaf vdev.  If this is an
3215  * import (mode is VDEV_ALLOC_SPARE), then we allow corrupted spares to be
3216  * specified, as long as they are well-formed.
3217  */
3218 static int
3219 spa_validate_aux_devs(spa_t *spa, nvlist_t *nvroot, uint64_t crtxg, int mode,
3220     spa_aux_vdev_t *sav, const char *config, uint64_t version,
3221     vdev_labeltype_t label)
3222 {
3223         nvlist_t **dev;
3224         uint_t i, ndev;
3225         vdev_t *vd;
3226         int error;
3227 
3228         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
3229 
3230         /*
3231          * It's acceptable to have no devs specified.
3232          */
3233         if (nvlist_lookup_nvlist_array(nvroot, config, &dev, &ndev) != 0)
3234                 return (0);
3235 
3236         if (ndev == 0)
3237                 return (SET_ERROR(EINVAL));
3238 
3239         /*
3240          * Make sure the pool is formatted with a version that supports this
3241          * device type.
3242          */
3243         if (spa_version(spa) < version)
3244                 return (SET_ERROR(ENOTSUP));
3245 
3246         /*
3247          * Set the pending device list so we correctly handle device in-use
3248          * checking.
3249          */
3250         sav->sav_pending = dev;
3251         sav->sav_npending = ndev;
3252 
3253         for (i = 0; i < ndev; i++) {
3254                 if ((error = spa_config_parse(spa, &vd, dev[i], NULL, 0,
3255                     mode)) != 0)
3256                         goto out;
3257 
3258                 if (!vd->vdev_ops->vdev_op_leaf) {
3259                         vdev_free(vd);
3260                         error = SET_ERROR(EINVAL);
3261                         goto out;
3262                 }
3263 
3264                 /*
3265                  * The L2ARC currently only supports disk devices in
3266                  * kernel context.  For user-level testing, we allow it.
3267                  */
3268 #ifdef _KERNEL
3269                 if ((strcmp(config, ZPOOL_CONFIG_L2CACHE) == 0) &&
3270                     strcmp(vd->vdev_ops->vdev_op_type, VDEV_TYPE_DISK) != 0) {
3271                         error = SET_ERROR(ENOTBLK);
3272                         vdev_free(vd);
3273                         goto out;
3274                 }
3275 #endif
3276                 vd->vdev_top = vd;
3277 
3278                 if ((error = vdev_open(vd)) == 0 &&
3279                     (error = vdev_label_init(vd, crtxg, label)) == 0) {
3280                         VERIFY(nvlist_add_uint64(dev[i], ZPOOL_CONFIG_GUID,
3281                             vd->vdev_guid) == 0);
3282                 }
3283 
3284                 vdev_free(vd);
3285 
3286                 if (error &&
3287                     (mode != VDEV_ALLOC_SPARE && mode != VDEV_ALLOC_L2CACHE))
3288                         goto out;
3289                 else
3290                         error = 0;
3291         }
3292 
3293 out:
3294         sav->sav_pending = NULL;
3295         sav->sav_npending = 0;
3296         return (error);
3297 }
3298 
3299 static int
3300 spa_validate_aux(spa_t *spa, nvlist_t *nvroot, uint64_t crtxg, int mode)
3301 {
3302         int error;
3303 
3304         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
3305 
3306         if ((error = spa_validate_aux_devs(spa, nvroot, crtxg, mode,
3307             &spa->spa_spares, ZPOOL_CONFIG_SPARES, SPA_VERSION_SPARES,
3308             VDEV_LABEL_SPARE)) != 0) {
3309                 return (error);
3310         }
3311 
3312         return (spa_validate_aux_devs(spa, nvroot, crtxg, mode,
3313             &spa->spa_l2cache, ZPOOL_CONFIG_L2CACHE, SPA_VERSION_L2CACHE,
3314             VDEV_LABEL_L2CACHE));
3315 }
3316 
3317 static void
3318 spa_set_aux_vdevs(spa_aux_vdev_t *sav, nvlist_t **devs, int ndevs,
3319     const char *config)
3320 {
3321         int i;
3322 
3323         if (sav->sav_config != NULL) {
3324                 nvlist_t **olddevs;
3325                 uint_t oldndevs;
3326                 nvlist_t **newdevs;
3327 
3328                 /*
3329                  * Generate new dev list by concatentating with the
3330                  * current dev list.
3331                  */
3332                 VERIFY(nvlist_lookup_nvlist_array(sav->sav_config, config,
3333                     &olddevs, &oldndevs) == 0);
3334 
3335                 newdevs = kmem_alloc(sizeof (void *) *
3336                     (ndevs + oldndevs), KM_SLEEP);
3337                 for (i = 0; i < oldndevs; i++)
3338                         VERIFY(nvlist_dup(olddevs[i], &newdevs[i],
3339                             KM_SLEEP) == 0);
3340                 for (i = 0; i < ndevs; i++)
3341                         VERIFY(nvlist_dup(devs[i], &newdevs[i + oldndevs],
3342                             KM_SLEEP) == 0);
3343 
3344                 VERIFY(nvlist_remove(sav->sav_config, config,
3345                     DATA_TYPE_NVLIST_ARRAY) == 0);
3346 
3347                 VERIFY(nvlist_add_nvlist_array(sav->sav_config,
3348                     config, newdevs, ndevs + oldndevs) == 0);
3349                 for (i = 0; i < oldndevs + ndevs; i++)
3350                         nvlist_free(newdevs[i]);
3351                 kmem_free(newdevs, (oldndevs + ndevs) * sizeof (void *));
3352         } else {
3353                 /*
3354                  * Generate a new dev list.
3355                  */
3356                 VERIFY(nvlist_alloc(&sav->sav_config, NV_UNIQUE_NAME,
3357                     KM_SLEEP) == 0);
3358                 VERIFY(nvlist_add_nvlist_array(sav->sav_config, config,
3359                     devs, ndevs) == 0);
3360         }
3361 }
3362 
3363 /*
3364  * Stop and drop level 2 ARC devices
3365  */
3366 void
3367 spa_l2cache_drop(spa_t *spa)
3368 {
3369         vdev_t *vd;
3370         int i;
3371         spa_aux_vdev_t *sav = &spa->spa_l2cache;
3372 
3373         for (i = 0; i < sav->sav_count; i++) {
3374                 uint64_t pool;
3375 
3376                 vd = sav->sav_vdevs[i];
3377                 ASSERT(vd != NULL);
3378 
3379                 if (spa_l2cache_exists(vd->vdev_guid, &pool) &&
3380                     pool != 0ULL && l2arc_vdev_present(vd))
3381                         l2arc_remove_vdev(vd);
3382         }
3383 }
3384 
3385 /*
3386  * Pool Creation
3387  */
3388 int
3389 spa_create(const char *pool, nvlist_t *nvroot, nvlist_t *props,
3390     nvlist_t *zplprops)
3391 {
3392         spa_t *spa;
3393         char *altroot = NULL;
3394         vdev_t *rvd;
3395         dsl_pool_t *dp;
3396         dmu_tx_t *tx;
3397         int error = 0;
3398         uint64_t txg = TXG_INITIAL;
3399         nvlist_t **spares, **l2cache;
3400         uint_t nspares, nl2cache;
3401         uint64_t version, obj;
3402         boolean_t has_features;
3403 
3404         /*
3405          * If this pool already exists, return failure.
3406          */
3407         mutex_enter(&spa_namespace_lock);
3408         if (spa_lookup(pool) != NULL) {
3409                 mutex_exit(&spa_namespace_lock);
3410                 return (SET_ERROR(EEXIST));
3411         }
3412 
3413         /*
3414          * Allocate a new spa_t structure.
3415          */
3416         (void) nvlist_lookup_string(props,
3417             zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
3418         spa = spa_add(pool, NULL, altroot);
3419         spa_activate(spa, spa_mode_global);
3420 
3421         if (props && (error = spa_prop_validate(spa, props))) {
3422                 spa_deactivate(spa);
3423                 spa_remove(spa);
3424                 mutex_exit(&spa_namespace_lock);
3425                 return (error);
3426         }
3427 
3428         has_features = B_FALSE;
3429         for (nvpair_t *elem = nvlist_next_nvpair(props, NULL);
3430             elem != NULL; elem = nvlist_next_nvpair(props, elem)) {
3431                 if (zpool_prop_feature(nvpair_name(elem)))
3432                         has_features = B_TRUE;
3433         }
3434 
3435         if (has_features || nvlist_lookup_uint64(props,
3436             zpool_prop_to_name(ZPOOL_PROP_VERSION), &version) != 0) {
3437                 version = SPA_VERSION;
3438         }
3439         ASSERT(SPA_VERSION_IS_SUPPORTED(version));
3440 
3441         spa->spa_first_txg = txg;
3442         spa->spa_uberblock.ub_txg = txg - 1;
3443         spa->spa_uberblock.ub_version = version;
3444         spa->spa_ubsync = spa->spa_uberblock;
3445 
3446         /*
3447          * Create "The Godfather" zio to hold all async IOs
3448          */
3449         spa->spa_async_zio_root = zio_root(spa, NULL, NULL,
3450             ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_GODFATHER);
3451 
3452         /*
3453          * Create the root vdev.
3454          */
3455         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3456 
3457         error = spa_config_parse(spa, &rvd, nvroot, NULL, 0, VDEV_ALLOC_ADD);
3458 
3459         ASSERT(error != 0 || rvd != NULL);
3460         ASSERT(error != 0 || spa->spa_root_vdev == rvd);
3461 
3462         if (error == 0 && !zfs_allocatable_devs(nvroot))
3463                 error = SET_ERROR(EINVAL);
3464 
3465         if (error == 0 &&
3466             (error = vdev_create(rvd, txg, B_FALSE)) == 0 &&
3467             (error = spa_validate_aux(spa, nvroot, txg,
3468             VDEV_ALLOC_ADD)) == 0) {
3469                 for (int c = 0; c < rvd->vdev_children; c++) {
3470                         vdev_metaslab_set_size(rvd->vdev_child[c]);
3471                         vdev_expand(rvd->vdev_child[c], txg);
3472                 }
3473         }
3474 
3475         spa_config_exit(spa, SCL_ALL, FTAG);
3476 
3477         if (error != 0) {
3478                 spa_unload(spa);
3479                 spa_deactivate(spa);
3480                 spa_remove(spa);
3481                 mutex_exit(&spa_namespace_lock);
3482                 return (error);
3483         }
3484 
3485         /*
3486          * Get the list of spares, if specified.
3487          */
3488         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
3489             &spares, &nspares) == 0) {
3490                 VERIFY(nvlist_alloc(&spa->spa_spares.sav_config, NV_UNIQUE_NAME,
3491                     KM_SLEEP) == 0);
3492                 VERIFY(nvlist_add_nvlist_array(spa->spa_spares.sav_config,
3493                     ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
3494                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3495                 spa_load_spares(spa);
3496                 spa_config_exit(spa, SCL_ALL, FTAG);
3497                 spa->spa_spares.sav_sync = B_TRUE;
3498         }
3499 
3500         /*
3501          * Get the list of level 2 cache devices, if specified.
3502          */
3503         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
3504             &l2cache, &nl2cache) == 0) {
3505                 VERIFY(nvlist_alloc(&spa->spa_l2cache.sav_config,
3506                     NV_UNIQUE_NAME, KM_SLEEP) == 0);
3507                 VERIFY(nvlist_add_nvlist_array(spa->spa_l2cache.sav_config,
3508                     ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
3509                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3510                 spa_load_l2cache(spa);
3511                 spa_config_exit(spa, SCL_ALL, FTAG);
3512                 spa->spa_l2cache.sav_sync = B_TRUE;
3513         }
3514 
3515         spa->spa_is_initializing = B_TRUE;
3516         spa->spa_dsl_pool = dp = dsl_pool_create(spa, zplprops, txg);
3517         spa->spa_meta_objset = dp->dp_meta_objset;
3518         spa->spa_is_initializing = B_FALSE;
3519 
3520         /*
3521          * Create DDTs (dedup tables).
3522          */
3523         ddt_create(spa);
3524 
3525         spa_update_dspace(spa);
3526 
3527         tx = dmu_tx_create_assigned(dp, txg);
3528 
3529         /*
3530          * Create the pool config object.
3531          */
3532         spa->spa_config_object = dmu_object_alloc(spa->spa_meta_objset,
3533             DMU_OT_PACKED_NVLIST, SPA_CONFIG_BLOCKSIZE,
3534             DMU_OT_PACKED_NVLIST_SIZE, sizeof (uint64_t), tx);
3535 
3536         if (zap_add(spa->spa_meta_objset,
3537             DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_CONFIG,
3538             sizeof (uint64_t), 1, &spa->spa_config_object, tx) != 0) {
3539                 cmn_err(CE_PANIC, "failed to add pool config");
3540         }
3541 
3542         if (spa_version(spa) >= SPA_VERSION_FEATURES)
3543                 spa_feature_create_zap_objects(spa, tx);
3544 
3545         if (zap_add(spa->spa_meta_objset,
3546             DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_CREATION_VERSION,
3547             sizeof (uint64_t), 1, &version, tx) != 0) {
3548                 cmn_err(CE_PANIC, "failed to add pool version");
3549         }
3550 
3551         /* Newly created pools with the right version are always deflated. */
3552         if (version >= SPA_VERSION_RAIDZ_DEFLATE) {
3553                 spa->spa_deflate = TRUE;
3554                 if (zap_add(spa->spa_meta_objset,
3555                     DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_DEFLATE,
3556                     sizeof (uint64_t), 1, &spa->spa_deflate, tx) != 0) {
3557                         cmn_err(CE_PANIC, "failed to add deflate");
3558                 }
3559         }
3560 
3561         /*
3562          * Create the deferred-free bpobj.  Turn off compression
3563          * because sync-to-convergence takes longer if the blocksize
3564          * keeps changing.
3565          */
3566         obj = bpobj_alloc(spa->spa_meta_objset, 1 << 14, tx);
3567         dmu_object_set_compress(spa->spa_meta_objset, obj,
3568             ZIO_COMPRESS_OFF, tx);
3569         if (zap_add(spa->spa_meta_objset,
3570             DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_SYNC_BPOBJ,
3571             sizeof (uint64_t), 1, &obj, tx) != 0) {
3572                 cmn_err(CE_PANIC, "failed to add bpobj");
3573         }
3574         VERIFY3U(0, ==, bpobj_open(&spa->spa_deferred_bpobj,
3575             spa->spa_meta_objset, obj));
3576 
3577         /*
3578          * Create the pool's history object.
3579          */
3580         if (version >= SPA_VERSION_ZPOOL_HISTORY)
3581                 spa_history_create_obj(spa, tx);
3582 
3583         /*
3584          * Set pool properties.
3585          */
3586         spa->spa_bootfs = zpool_prop_default_numeric(ZPOOL_PROP_BOOTFS);
3587         spa->spa_delegation = zpool_prop_default_numeric(ZPOOL_PROP_DELEGATION);
3588         spa->spa_failmode = zpool_prop_default_numeric(ZPOOL_PROP_FAILUREMODE);
3589         spa->spa_autoexpand = zpool_prop_default_numeric(ZPOOL_PROP_AUTOEXPAND);
3590 
3591         if (props != NULL) {
3592                 spa_configfile_set(spa, props, B_FALSE);
3593                 spa_sync_props(props, tx);
3594         }
3595 
3596         dmu_tx_commit(tx);
3597 
3598         spa->spa_sync_on = B_TRUE;
3599         txg_sync_start(spa->spa_dsl_pool);
3600 
3601         /*
3602          * We explicitly wait for the first transaction to complete so that our
3603          * bean counters are appropriately updated.
3604          */
3605         txg_wait_synced(spa->spa_dsl_pool, txg);
3606 
3607         spa_config_sync(spa, B_FALSE, B_TRUE);
3608 
3609         spa_history_log_version(spa, "create");
3610 
3611         spa->spa_minref = refcount_count(&spa->spa_refcount);
3612 
3613         mutex_exit(&spa_namespace_lock);
3614 
3615         return (0);
3616 }
3617 
3618 #ifdef _KERNEL
3619 /*
3620  * Get the root pool information from the root disk, then import the root pool
3621  * during the system boot up time.
3622  */
3623 extern int vdev_disk_read_rootlabel(char *, char *, nvlist_t **);
3624 
3625 static nvlist_t *
3626 spa_generate_rootconf(char *devpath, char *devid, uint64_t *guid)
3627 {
3628         nvlist_t *config;
3629         nvlist_t *nvtop, *nvroot;
3630         uint64_t pgid;
3631 
3632         if (vdev_disk_read_rootlabel(devpath, devid, &config) != 0)
3633                 return (NULL);
3634 
3635         /*
3636          * Add this top-level vdev to the child array.
3637          */
3638         VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
3639             &nvtop) == 0);
3640         VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
3641             &pgid) == 0);
3642         VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID, guid) == 0);
3643 
3644         /*
3645          * Put this pool's top-level vdevs into a root vdev.
3646          */
3647         VERIFY(nvlist_alloc(&nvroot, NV_UNIQUE_NAME, KM_SLEEP) == 0);
3648         VERIFY(nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
3649             VDEV_TYPE_ROOT) == 0);
3650         VERIFY(nvlist_add_uint64(nvroot, ZPOOL_CONFIG_ID, 0ULL) == 0);
3651         VERIFY(nvlist_add_uint64(nvroot, ZPOOL_CONFIG_GUID, pgid) == 0);
3652         VERIFY(nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
3653             &nvtop, 1) == 0);
3654 
3655         /*
3656          * Replace the existing vdev_tree with the new root vdev in
3657          * this pool's configuration (remove the old, add the new).
3658          */
3659         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0);
3660         nvlist_free(nvroot);
3661         return (config);
3662 }
3663 
3664 /*
3665  * Walk the vdev tree and see if we can find a device with "better"
3666  * configuration. A configuration is "better" if the label on that
3667  * device has a more recent txg.
3668  */
3669 static void
3670 spa_alt_rootvdev(vdev_t *vd, vdev_t **avd, uint64_t *txg)
3671 {
3672         for (int c = 0; c < vd->vdev_children; c++)
3673                 spa_alt_rootvdev(vd->vdev_child[c], avd, txg);
3674 
3675         if (vd->vdev_ops->vdev_op_leaf) {
3676                 nvlist_t *label;
3677                 uint64_t label_txg;
3678 
3679                 if (vdev_disk_read_rootlabel(vd->vdev_physpath, vd->vdev_devid,
3680                     &label) != 0)
3681                         return;
3682 
3683                 VERIFY(nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG,
3684                     &label_txg) == 0);
3685 
3686                 /*
3687                  * Do we have a better boot device?
3688                  */
3689                 if (label_txg > *txg) {
3690                         *txg = label_txg;
3691                         *avd = vd;
3692                 }
3693                 nvlist_free(label);
3694         }
3695 }
3696 
3697 /*
3698  * Import a root pool.
3699  *
3700  * For x86. devpath_list will consist of devid and/or physpath name of
3701  * the vdev (e.g. "id1,sd@SSEAGATE..." or "/pci@1f,0/ide@d/disk@0,0:a").
3702  * The GRUB "findroot" command will return the vdev we should boot.
3703  *
3704  * For Sparc, devpath_list consists the physpath name of the booting device
3705  * no matter the rootpool is a single device pool or a mirrored pool.
3706  * e.g.
3707  *      "/pci@1f,0/ide@d/disk@0,0:a"
3708  */
3709 int
3710 spa_import_rootpool(char *devpath, char *devid)
3711 {
3712         spa_t *spa;
3713         vdev_t *rvd, *bvd, *avd = NULL;
3714         nvlist_t *config, *nvtop;
3715         uint64_t guid, txg;
3716         char *pname;
3717         int error;
3718 
3719         /*
3720          * Read the label from the boot device and generate a configuration.
3721          */
3722         config = spa_generate_rootconf(devpath, devid, &guid);
3723 #if defined(_OBP) && defined(_KERNEL)
3724         if (config == NULL) {
3725                 if (strstr(devpath, "/iscsi/ssd") != NULL) {
3726                         /* iscsi boot */
3727                         get_iscsi_bootpath_phy(devpath);
3728                         config = spa_generate_rootconf(devpath, devid, &guid);
3729                 }
3730         }
3731 #endif
3732         if (config == NULL) {
3733                 cmn_err(CE_NOTE, "Cannot read the pool label from '%s'",
3734                     devpath);
3735                 return (SET_ERROR(EIO));
3736         }
3737 
3738         VERIFY(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
3739             &pname) == 0);
3740         VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG, &txg) == 0);
3741 
3742         mutex_enter(&spa_namespace_lock);
3743         if ((spa = spa_lookup(pname)) != NULL) {
3744                 /*
3745                  * Remove the existing root pool from the namespace so that we
3746                  * can replace it with the correct config we just read in.
3747                  */
3748                 spa_remove(spa);
3749         }
3750 
3751         spa = spa_add(pname, config, NULL);
3752         spa->spa_is_root = B_TRUE;
3753         spa->spa_import_flags = ZFS_IMPORT_VERBATIM;
3754 
3755         /*
3756          * Build up a vdev tree based on the boot device's label config.
3757          */
3758         VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
3759             &nvtop) == 0);
3760         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3761         error = spa_config_parse(spa, &rvd, nvtop, NULL, 0,
3762             VDEV_ALLOC_ROOTPOOL);
3763         spa_config_exit(spa, SCL_ALL, FTAG);
3764         if (error) {
3765                 mutex_exit(&spa_namespace_lock);
3766                 nvlist_free(config);
3767                 cmn_err(CE_NOTE, "Can not parse the config for pool '%s'",
3768                     pname);
3769                 return (error);
3770         }
3771 
3772         /*
3773          * Get the boot vdev.
3774          */
3775         if ((bvd = vdev_lookup_by_guid(rvd, guid)) == NULL) {
3776                 cmn_err(CE_NOTE, "Can not find the boot vdev for guid %llu",
3777                     (u_longlong_t)guid);
3778                 error = SET_ERROR(ENOENT);
3779                 goto out;
3780         }
3781 
3782         /*
3783          * Determine if there is a better boot device.
3784          */
3785         avd = bvd;
3786         spa_alt_rootvdev(rvd, &avd, &txg);
3787         if (avd != bvd) {
3788                 cmn_err(CE_NOTE, "The boot device is 'degraded'. Please "
3789                     "try booting from '%s'", avd->vdev_path);
3790                 error = SET_ERROR(EINVAL);
3791                 goto out;
3792         }
3793 
3794         /*
3795          * If the boot device is part of a spare vdev then ensure that
3796          * we're booting off the active spare.
3797          */
3798         if (bvd->vdev_parent->vdev_ops == &vdev_spare_ops &&
3799             !bvd->vdev_isspare) {
3800                 cmn_err(CE_NOTE, "The boot device is currently spared. Please "
3801                     "try booting from '%s'",
3802                     bvd->vdev_parent->
3803                     vdev_child[bvd->vdev_parent->vdev_children - 1]->vdev_path);
3804                 error = SET_ERROR(EINVAL);
3805                 goto out;
3806         }
3807 
3808         error = 0;
3809 out:
3810         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3811         vdev_free(rvd);
3812         spa_config_exit(spa, SCL_ALL, FTAG);
3813         mutex_exit(&spa_namespace_lock);
3814 
3815         nvlist_free(config);
3816         return (error);
3817 }
3818 
3819 #endif
3820 
3821 /*
3822  * Import a non-root pool into the system.
3823  */
3824 int
3825 spa_import(const char *pool, nvlist_t *config, nvlist_t *props, uint64_t flags)
3826 {
3827         spa_t *spa;
3828         char *altroot = NULL;
3829         spa_load_state_t state = SPA_LOAD_IMPORT;
3830         zpool_rewind_policy_t policy;
3831         uint64_t mode = spa_mode_global;
3832         uint64_t readonly = B_FALSE;
3833         int error;
3834         nvlist_t *nvroot;
3835         nvlist_t **spares, **l2cache;
3836         uint_t nspares, nl2cache;
3837 
3838         /*
3839          * If a pool with this name exists, return failure.
3840          */
3841         mutex_enter(&spa_namespace_lock);
3842         if (spa_lookup(pool) != NULL) {
3843                 mutex_exit(&spa_namespace_lock);
3844                 return (SET_ERROR(EEXIST));
3845         }
3846 
3847         /*
3848          * Create and initialize the spa structure.
3849          */
3850         (void) nvlist_lookup_string(props,
3851             zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
3852         (void) nvlist_lookup_uint64(props,
3853             zpool_prop_to_name(ZPOOL_PROP_READONLY), &readonly);
3854         if (readonly)
3855                 mode = FREAD;
3856         spa = spa_add(pool, config, altroot);
3857         spa->spa_import_flags = flags;
3858 
3859         /*
3860          * Verbatim import - Take a pool and insert it into the namespace
3861          * as if it had been loaded at boot.
3862          */
3863         if (spa->spa_import_flags & ZFS_IMPORT_VERBATIM) {
3864                 if (props != NULL)
3865                         spa_configfile_set(spa, props, B_FALSE);
3866 
3867                 spa_config_sync(spa, B_FALSE, B_TRUE);
3868 
3869                 mutex_exit(&spa_namespace_lock);
3870                 return (0);
3871         }
3872 
3873         spa_activate(spa, mode);
3874 
3875         /*
3876          * Don't start async tasks until we know everything is healthy.
3877          */
3878         spa_async_suspend(spa);
3879 
3880         zpool_get_rewind_policy(config, &policy);
3881         if (policy.zrp_request & ZPOOL_DO_REWIND)
3882                 state = SPA_LOAD_RECOVER;
3883 
3884         /*
3885          * Pass off the heavy lifting to spa_load().  Pass TRUE for mosconfig
3886          * because the user-supplied config is actually the one to trust when
3887          * doing an import.
3888          */
3889         if (state != SPA_LOAD_RECOVER)
3890                 spa->spa_last_ubsync_txg = spa->spa_load_txg = 0;
3891 
3892         error = spa_load_best(spa, state, B_TRUE, policy.zrp_txg,
3893             policy.zrp_request);
3894 
3895         /*
3896          * Propagate anything learned while loading the pool and pass it
3897          * back to caller (i.e. rewind info, missing devices, etc).
3898          */
3899         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_LOAD_INFO,
3900             spa->spa_load_info) == 0);
3901 
3902         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3903         /*
3904          * Toss any existing sparelist, as it doesn't have any validity
3905          * anymore, and conflicts with spa_has_spare().
3906          */
3907         if (spa->spa_spares.sav_config) {
3908                 nvlist_free(spa->spa_spares.sav_config);
3909                 spa->spa_spares.sav_config = NULL;
3910                 spa_load_spares(spa);
3911         }
3912         if (spa->spa_l2cache.sav_config) {
3913                 nvlist_free(spa->spa_l2cache.sav_config);
3914                 spa->spa_l2cache.sav_config = NULL;
3915                 spa_load_l2cache(spa);
3916         }
3917 
3918         VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
3919             &nvroot) == 0);
3920         if (error == 0)
3921                 error = spa_validate_aux(spa, nvroot, -1ULL,
3922                     VDEV_ALLOC_SPARE);
3923         if (error == 0)
3924                 error = spa_validate_aux(spa, nvroot, -1ULL,
3925                     VDEV_ALLOC_L2CACHE);
3926         spa_config_exit(spa, SCL_ALL, FTAG);
3927 
3928         if (props != NULL)
3929                 spa_configfile_set(spa, props, B_FALSE);
3930 
3931         if (error != 0 || (props && spa_writeable(spa) &&
3932             (error = spa_prop_set(spa, props)))) {
3933                 spa_unload(spa);
3934                 spa_deactivate(spa);
3935                 spa_remove(spa);
3936                 mutex_exit(&spa_namespace_lock);
3937                 return (error);
3938         }
3939 
3940         spa_async_resume(spa);
3941 
3942         /*
3943          * Override any spares and level 2 cache devices as specified by
3944          * the user, as these may have correct device names/devids, etc.
3945          */
3946         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
3947             &spares, &nspares) == 0) {
3948                 if (spa->spa_spares.sav_config)
3949                         VERIFY(nvlist_remove(spa->spa_spares.sav_config,
3950                             ZPOOL_CONFIG_SPARES, DATA_TYPE_NVLIST_ARRAY) == 0);
3951                 else
3952                         VERIFY(nvlist_alloc(&spa->spa_spares.sav_config,
3953                             NV_UNIQUE_NAME, KM_SLEEP) == 0);
3954                 VERIFY(nvlist_add_nvlist_array(spa->spa_spares.sav_config,
3955                     ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
3956                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3957                 spa_load_spares(spa);
3958                 spa_config_exit(spa, SCL_ALL, FTAG);
3959                 spa->spa_spares.sav_sync = B_TRUE;
3960         }
3961         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
3962             &l2cache, &nl2cache) == 0) {
3963                 if (spa->spa_l2cache.sav_config)
3964                         VERIFY(nvlist_remove(spa->spa_l2cache.sav_config,
3965                             ZPOOL_CONFIG_L2CACHE, DATA_TYPE_NVLIST_ARRAY) == 0);
3966                 else
3967                         VERIFY(nvlist_alloc(&spa->spa_l2cache.sav_config,
3968                             NV_UNIQUE_NAME, KM_SLEEP) == 0);
3969                 VERIFY(nvlist_add_nvlist_array(spa->spa_l2cache.sav_config,
3970                     ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
3971                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3972                 spa_load_l2cache(spa);
3973                 spa_config_exit(spa, SCL_ALL, FTAG);
3974                 spa->spa_l2cache.sav_sync = B_TRUE;
3975         }
3976 
3977         /*
3978          * Check for any removed devices.
3979          */
3980         if (spa->spa_autoreplace) {
3981                 spa_aux_check_removed(&spa->spa_spares);
3982                 spa_aux_check_removed(&spa->spa_l2cache);
3983         }
3984 
3985         if (spa_writeable(spa)) {
3986                 /*
3987                  * Update the config cache to include the newly-imported pool.
3988                  */
3989                 spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
3990         }
3991 
3992         /*
3993          * It's possible that the pool was expanded while it was exported.
3994          * We kick off an async task to handle this for us.
3995          */
3996         spa_async_request(spa, SPA_ASYNC_AUTOEXPAND);
3997 
3998         mutex_exit(&spa_namespace_lock);
3999         spa_history_log_version(spa, "import");
4000 
4001         return (0);
4002 }
4003 
4004 nvlist_t *
4005 spa_tryimport(nvlist_t *tryconfig)
4006 {
4007         nvlist_t *config = NULL;
4008         char *poolname;
4009         spa_t *spa;
4010         uint64_t state;
4011         int error;
4012 
4013         if (nvlist_lookup_string(tryconfig, ZPOOL_CONFIG_POOL_NAME, &poolname))
4014                 return (NULL);
4015 
4016         if (nvlist_lookup_uint64(tryconfig, ZPOOL_CONFIG_POOL_STATE, &state))
4017                 return (NULL);
4018 
4019         /*
4020          * Create and initialize the spa structure.
4021          */
4022         mutex_enter(&spa_namespace_lock);
4023         spa = spa_add(TRYIMPORT_NAME, tryconfig, NULL);
4024         spa_activate(spa, FREAD);
4025 
4026         /*
4027          * Pass off the heavy lifting to spa_load().
4028          * Pass TRUE for mosconfig because the user-supplied config
4029          * is actually the one to trust when doing an import.
4030          */
4031         error = spa_load(spa, SPA_LOAD_TRYIMPORT, SPA_IMPORT_EXISTING, B_TRUE);
4032 
4033         /*
4034          * If 'tryconfig' was at least parsable, return the current config.
4035          */
4036         if (spa->spa_root_vdev != NULL) {
4037                 config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
4038                 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME,
4039                     poolname) == 0);
4040                 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
4041                     state) == 0);
4042                 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TIMESTAMP,
4043                     spa->spa_uberblock.ub_timestamp) == 0);
4044                 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_LOAD_INFO,
4045                     spa->spa_load_info) == 0);
4046 
4047                 /*
4048                  * If the bootfs property exists on this pool then we
4049                  * copy it out so that external consumers can tell which
4050                  * pools are bootable.
4051                  */
4052                 if ((!error || error == EEXIST) && spa->spa_bootfs) {
4053                         char *tmpname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
4054 
4055                         /*
4056                          * We have to play games with the name since the
4057                          * pool was opened as TRYIMPORT_NAME.
4058                          */
4059                         if (dsl_dsobj_to_dsname(spa_name(spa),
4060                             spa->spa_bootfs, tmpname) == 0) {
4061                                 char *cp;
4062                                 char *dsname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
4063 
4064                                 cp = strchr(tmpname, '/');
4065                                 if (cp == NULL) {
4066                                         (void) strlcpy(dsname, tmpname,
4067                                             MAXPATHLEN);
4068                                 } else {
4069                                         (void) snprintf(dsname, MAXPATHLEN,
4070                                             "%s/%s", poolname, ++cp);
4071                                 }
4072                                 VERIFY(nvlist_add_string(config,
4073                                     ZPOOL_CONFIG_BOOTFS, dsname) == 0);
4074                                 kmem_free(dsname, MAXPATHLEN);
4075                         }
4076                         kmem_free(tmpname, MAXPATHLEN);
4077                 }
4078 
4079                 /*
4080                  * Add the list of hot spares and level 2 cache devices.
4081                  */
4082                 spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
4083                 spa_add_spares(spa, config);
4084                 spa_add_l2cache(spa, config);
4085                 spa_config_exit(spa, SCL_CONFIG, FTAG);
4086         }
4087 
4088         spa_unload(spa);
4089         spa_deactivate(spa);
4090         spa_remove(spa);
4091         mutex_exit(&spa_namespace_lock);
4092 
4093         return (config);
4094 }
4095 
4096 /*
4097  * Pool export/destroy
4098  *
4099  * The act of destroying or exporting a pool is very simple.  We make sure there
4100  * is no more pending I/O and any references to the pool are gone.  Then, we
4101  * update the pool state and sync all the labels to disk, removing the
4102  * configuration from the cache afterwards. If the 'hardforce' flag is set, then
4103  * we don't sync the labels or remove the configuration cache.
4104  */
4105 static int
4106 spa_export_common(char *pool, int new_state, nvlist_t **oldconfig,
4107     boolean_t force, boolean_t hardforce)
4108 {
4109         spa_t *spa;
4110 
4111         if (oldconfig)
4112                 *oldconfig = NULL;
4113 
4114         if (!(spa_mode_global & FWRITE))
4115                 return (SET_ERROR(EROFS));
4116 
4117         mutex_enter(&spa_namespace_lock);
4118         if ((spa = spa_lookup(pool)) == NULL) {
4119                 mutex_exit(&spa_namespace_lock);
4120                 return (SET_ERROR(ENOENT));
4121         }
4122 
4123         /*
4124          * Put a hold on the pool, drop the namespace lock, stop async tasks,
4125          * reacquire the namespace lock, and see if we can export.
4126          */
4127         spa_open_ref(spa, FTAG);
4128         mutex_exit(&spa_namespace_lock);
4129         spa_async_suspend(spa);
4130         mutex_enter(&spa_namespace_lock);
4131         spa_close(spa, FTAG);
4132 
4133         /*
4134          * The pool will be in core if it's openable,
4135          * in which case we can modify its state.
4136          */
4137         if (spa->spa_state != POOL_STATE_UNINITIALIZED && spa->spa_sync_on) {
4138                 /*
4139                  * Objsets may be open only because they're dirty, so we
4140                  * have to force it to sync before checking spa_refcnt.
4141                  */
4142                 txg_wait_synced(spa->spa_dsl_pool, 0);
4143 
4144                 /*
4145                  * A pool cannot be exported or destroyed if there are active
4146                  * references.  If we are resetting a pool, allow references by
4147                  * fault injection handlers.
4148                  */
4149                 if (!spa_refcount_zero(spa) ||
4150                     (spa->spa_inject_ref != 0 &&
4151                     new_state != POOL_STATE_UNINITIALIZED)) {
4152                         spa_async_resume(spa);
4153                         mutex_exit(&spa_namespace_lock);
4154                         return (SET_ERROR(EBUSY));
4155                 }
4156 
4157                 /*
4158                  * A pool cannot be exported if it has an active shared spare.
4159                  * This is to prevent other pools stealing the active spare
4160                  * from an exported pool. At user's own will, such pool can
4161                  * be forcedly exported.
4162                  */
4163                 if (!force && new_state == POOL_STATE_EXPORTED &&
4164                     spa_has_active_shared_spare(spa)) {
4165                         spa_async_resume(spa);
4166                         mutex_exit(&spa_namespace_lock);
4167                         return (SET_ERROR(EXDEV));
4168                 }
4169 
4170                 /*
4171                  * We want this to be reflected on every label,
4172                  * so mark them all dirty.  spa_unload() will do the
4173                  * final sync that pushes these changes out.
4174                  */
4175                 if (new_state != POOL_STATE_UNINITIALIZED && !hardforce) {
4176                         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
4177                         spa->spa_state = new_state;
4178                         spa->spa_final_txg = spa_last_synced_txg(spa) +
4179                             TXG_DEFER_SIZE + 1;
4180                         vdev_config_dirty(spa->spa_root_vdev);
4181                         spa_config_exit(spa, SCL_ALL, FTAG);
4182                 }
4183         }
4184 
4185         spa_event_notify(spa, NULL, ESC_ZFS_POOL_DESTROY);
4186 
4187         if (spa->spa_state != POOL_STATE_UNINITIALIZED) {
4188                 spa_unload(spa);
4189                 spa_deactivate(spa);
4190         }
4191 
4192         if (oldconfig && spa->spa_config)
4193                 VERIFY(nvlist_dup(spa->spa_config, oldconfig, 0) == 0);
4194 
4195         if (new_state != POOL_STATE_UNINITIALIZED) {
4196                 if (!hardforce)
4197                         spa_config_sync(spa, B_TRUE, B_TRUE);
4198                 spa_remove(spa);
4199         }
4200         mutex_exit(&spa_namespace_lock);
4201 
4202         return (0);
4203 }
4204 
4205 /*
4206  * Destroy a storage pool.
4207  */
4208 int
4209 spa_destroy(char *pool)
4210 {
4211         return (spa_export_common(pool, POOL_STATE_DESTROYED, NULL,
4212             B_FALSE, B_FALSE));
4213 }
4214 
4215 /*
4216  * Export a storage pool.
4217  */
4218 int
4219 spa_export(char *pool, nvlist_t **oldconfig, boolean_t force,
4220     boolean_t hardforce)
4221 {
4222         return (spa_export_common(pool, POOL_STATE_EXPORTED, oldconfig,
4223             force, hardforce));
4224 }
4225 
4226 /*
4227  * Similar to spa_export(), this unloads the spa_t without actually removing it
4228  * from the namespace in any way.
4229  */
4230 int
4231 spa_reset(char *pool)
4232 {
4233         return (spa_export_common(pool, POOL_STATE_UNINITIALIZED, NULL,
4234             B_FALSE, B_FALSE));
4235 }
4236 
4237 /*
4238  * ==========================================================================
4239  * Device manipulation
4240  * ==========================================================================
4241  */
4242 
4243 /*
4244  * Add a device to a storage pool.
4245  */
4246 int
4247 spa_vdev_add(spa_t *spa, nvlist_t *nvroot)
4248 {
4249         uint64_t txg, id;
4250         int error;
4251         vdev_t *rvd = spa->spa_root_vdev;
4252         vdev_t *vd, *tvd;
4253         nvlist_t **spares, **l2cache;
4254         uint_t nspares, nl2cache;
4255 
4256         ASSERT(spa_writeable(spa));
4257 
4258         txg = spa_vdev_enter(spa);
4259 
4260         if ((error = spa_config_parse(spa, &vd, nvroot, NULL, 0,
4261             VDEV_ALLOC_ADD)) != 0)
4262                 return (spa_vdev_exit(spa, NULL, txg, error));
4263 
4264         spa->spa_pending_vdev = vd;  /* spa_vdev_exit() will clear this */
4265 
4266         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES, &spares,
4267             &nspares) != 0)
4268                 nspares = 0;
4269 
4270         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE, &l2cache,
4271             &nl2cache) != 0)
4272                 nl2cache = 0;
4273 
4274         if (vd->vdev_children == 0 && nspares == 0 && nl2cache == 0)
4275                 return (spa_vdev_exit(spa, vd, txg, EINVAL));
4276 
4277         if (vd->vdev_children != 0 &&
4278             (error = vdev_create(vd, txg, B_FALSE)) != 0)
4279                 return (spa_vdev_exit(spa, vd, txg, error));
4280 
4281         /*
4282          * We must validate the spares and l2cache devices after checking the
4283          * children.  Otherwise, vdev_inuse() will blindly overwrite the spare.
4284          */
4285         if ((error = spa_validate_aux(spa, nvroot, txg, VDEV_ALLOC_ADD)) != 0)
4286                 return (spa_vdev_exit(spa, vd, txg, error));
4287 
4288         /*
4289          * Transfer each new top-level vdev from vd to rvd.
4290          */
4291         for (int c = 0; c < vd->vdev_children; c++) {
4292 
4293                 /*
4294                  * Set the vdev id to the first hole, if one exists.
4295                  */
4296                 for (id = 0; id < rvd->vdev_children; id++) {
4297                         if (rvd->vdev_child[id]->vdev_ishole) {
4298                                 vdev_free(rvd->vdev_child[id]);
4299                                 break;
4300                         }
4301                 }
4302                 tvd = vd->vdev_child[c];
4303                 vdev_remove_child(vd, tvd);
4304                 tvd->vdev_id = id;
4305                 vdev_add_child(rvd, tvd);
4306                 vdev_config_dirty(tvd);
4307         }
4308 
4309         if (nspares != 0) {
4310                 spa_set_aux_vdevs(&spa->spa_spares, spares, nspares,
4311                     ZPOOL_CONFIG_SPARES);
4312                 spa_load_spares(spa);
4313                 spa->spa_spares.sav_sync = B_TRUE;
4314         }
4315 
4316         if (nl2cache != 0) {
4317                 spa_set_aux_vdevs(&spa->spa_l2cache, l2cache, nl2cache,
4318                     ZPOOL_CONFIG_L2CACHE);
4319                 spa_load_l2cache(spa);
4320                 spa->spa_l2cache.sav_sync = B_TRUE;
4321         }
4322 
4323         /*
4324          * We have to be careful when adding new vdevs to an existing pool.
4325          * If other threads start allocating from these vdevs before we
4326          * sync the config cache, and we lose power, then upon reboot we may
4327          * fail to open the pool because there are DVAs that the config cache
4328          * can't translate.  Therefore, we first add the vdevs without
4329          * initializing metaslabs; sync the config cache (via spa_vdev_exit());
4330          * and then let spa_config_update() initialize the new metaslabs.
4331          *
4332          * spa_load() checks for added-but-not-initialized vdevs, so that
4333          * if we lose power at any point in this sequence, the remaining
4334          * steps will be completed the next time we load the pool.
4335          */
4336         (void) spa_vdev_exit(spa, vd, txg, 0);
4337 
4338         mutex_enter(&spa_namespace_lock);
4339         spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
4340         mutex_exit(&spa_namespace_lock);
4341 
4342         return (0);
4343 }
4344 
4345 /*
4346  * Attach a device to a mirror.  The arguments are the path to any device
4347  * in the mirror, and the nvroot for the new device.  If the path specifies
4348  * a device that is not mirrored, we automatically insert the mirror vdev.
4349  *
4350  * If 'replacing' is specified, the new device is intended to replace the
4351  * existing device; in this case the two devices are made into their own
4352  * mirror using the 'replacing' vdev, which is functionally identical to
4353  * the mirror vdev (it actually reuses all the same ops) but has a few
4354  * extra rules: you can't attach to it after it's been created, and upon
4355  * completion of resilvering, the first disk (the one being replaced)
4356  * is automatically detached.
4357  */
4358 int
4359 spa_vdev_attach(spa_t *spa, uint64_t guid, nvlist_t *nvroot, int replacing)
4360 {
4361         uint64_t txg, dtl_max_txg;
4362         vdev_t *rvd = spa->spa_root_vdev;
4363         vdev_t *oldvd, *newvd, *newrootvd, *pvd, *tvd;
4364         vdev_ops_t *pvops;
4365         char *oldvdpath, *newvdpath;
4366         int newvd_isspare;
4367         int error;
4368 
4369         ASSERT(spa_writeable(spa));
4370 
4371         txg = spa_vdev_enter(spa);
4372 
4373         oldvd = spa_lookup_by_guid(spa, guid, B_FALSE);
4374 
4375         if (oldvd == NULL)
4376                 return (spa_vdev_exit(spa, NULL, txg, ENODEV));
4377 
4378         if (!oldvd->vdev_ops->vdev_op_leaf)
4379                 return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
4380 
4381         pvd = oldvd->vdev_parent;
4382 
4383         if ((error = spa_config_parse(spa, &newrootvd, nvroot, NULL, 0,
4384             VDEV_ALLOC_ATTACH)) != 0)
4385                 return (spa_vdev_exit(spa, NULL, txg, EINVAL));
4386 
4387         if (newrootvd->vdev_children != 1)
4388                 return (spa_vdev_exit(spa, newrootvd, txg, EINVAL));
4389 
4390         newvd = newrootvd->vdev_child[0];
4391 
4392         if (!newvd->vdev_ops->vdev_op_leaf)
4393                 return (spa_vdev_exit(spa, newrootvd, txg, EINVAL));
4394 
4395         if ((error = vdev_create(newrootvd, txg, replacing)) != 0)
4396                 return (spa_vdev_exit(spa, newrootvd, txg, error));
4397 
4398         /*
4399          * Spares can't replace logs
4400          */
4401         if (oldvd->vdev_top->vdev_islog && newvd->vdev_isspare)
4402                 return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4403 
4404         if (!replacing) {
4405                 /*
4406                  * For attach, the only allowable parent is a mirror or the root
4407                  * vdev.
4408                  */
4409                 if (pvd->vdev_ops != &vdev_mirror_ops &&
4410                     pvd->vdev_ops != &vdev_root_ops)
4411                         return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4412 
4413                 pvops = &vdev_mirror_ops;
4414         } else {
4415                 /*
4416                  * Active hot spares can only be replaced by inactive hot
4417                  * spares.
4418                  */
4419                 if (pvd->vdev_ops == &vdev_spare_ops &&
4420                     oldvd->vdev_isspare &&
4421                     !spa_has_spare(spa, newvd->vdev_guid))
4422                         return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4423 
4424                 /*
4425                  * If the source is a hot spare, and the parent isn't already a
4426                  * spare, then we want to create a new hot spare.  Otherwise, we
4427                  * want to create a replacing vdev.  The user is not allowed to
4428                  * attach to a spared vdev child unless the 'isspare' state is
4429                  * the same (spare replaces spare, non-spare replaces
4430                  * non-spare).
4431                  */
4432                 if (pvd->vdev_ops == &vdev_replacing_ops &&
4433                     spa_version(spa) < SPA_VERSION_MULTI_REPLACE) {
4434                         return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4435                 } else if (pvd->vdev_ops == &vdev_spare_ops &&
4436                     newvd->vdev_isspare != oldvd->vdev_isspare) {
4437                         return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4438                 }
4439 
4440                 if (newvd->vdev_isspare)
4441                         pvops = &vdev_spare_ops;
4442                 else
4443                         pvops = &vdev_replacing_ops;
4444         }
4445 
4446         /*
4447          * Make sure the new device is big enough.
4448          */
4449         if (newvd->vdev_asize < vdev_get_min_asize(oldvd))
4450                 return (spa_vdev_exit(spa, newrootvd, txg, EOVERFLOW));
4451 
4452         /*
4453          * The new device cannot have a higher alignment requirement
4454          * than the top-level vdev.
4455          */
4456         if (newvd->vdev_ashift > oldvd->vdev_top->vdev_ashift)
4457                 return (spa_vdev_exit(spa, newrootvd, txg, EDOM));
4458 
4459         /*
4460          * If this is an in-place replacement, update oldvd's path and devid
4461          * to make it distinguishable from newvd, and unopenable from now on.
4462          */
4463         if (strcmp(oldvd->vdev_path, newvd->vdev_path) == 0) {
4464                 spa_strfree(oldvd->vdev_path);
4465                 oldvd->vdev_path = kmem_alloc(strlen(newvd->vdev_path) + 5,
4466                     KM_SLEEP);
4467                 (void) sprintf(oldvd->vdev_path, "%s/%s",
4468                     newvd->vdev_path, "old");
4469                 if (oldvd->vdev_devid != NULL) {
4470                         spa_strfree(oldvd->vdev_devid);
4471                         oldvd->vdev_devid = NULL;
4472                 }
4473         }
4474 
4475         /* mark the device being resilvered */
4476         newvd->vdev_resilver_txg = txg;
4477 
4478         /*
4479          * If the parent is not a mirror, or if we're replacing, insert the new
4480          * mirror/replacing/spare vdev above oldvd.
4481          */
4482         if (pvd->vdev_ops != pvops)
4483                 pvd = vdev_add_parent(oldvd, pvops);
4484 
4485         ASSERT(pvd->vdev_top->vdev_parent == rvd);
4486         ASSERT(pvd->vdev_ops == pvops);
4487         ASSERT(oldvd->vdev_parent == pvd);
4488 
4489         /*
4490          * Extract the new device from its root and add it to pvd.
4491          */
4492         vdev_remove_child(newrootvd, newvd);
4493         newvd->vdev_id = pvd->vdev_children;
4494         newvd->vdev_crtxg = oldvd->vdev_crtxg;
4495         vdev_add_child(pvd, newvd);
4496 
4497         tvd = newvd->vdev_top;
4498         ASSERT(pvd->vdev_top == tvd);
4499         ASSERT(tvd->vdev_parent == rvd);
4500 
4501         vdev_config_dirty(tvd);
4502 
4503         /*
4504          * Set newvd's DTL to [TXG_INITIAL, dtl_max_txg) so that we account
4505          * for any dmu_sync-ed blocks.  It will propagate upward when
4506          * spa_vdev_exit() calls vdev_dtl_reassess().
4507          */
4508         dtl_max_txg = txg + TXG_CONCURRENT_STATES;
4509 
4510         vdev_dtl_dirty(newvd, DTL_MISSING, TXG_INITIAL,
4511             dtl_max_txg - TXG_INITIAL);
4512 
4513         if (newvd->vdev_isspare) {
4514                 spa_spare_activate(newvd);
4515                 spa_event_notify(spa, newvd, ESC_ZFS_VDEV_SPARE);
4516         }
4517 
4518         oldvdpath = spa_strdup(oldvd->vdev_path);
4519         newvdpath = spa_strdup(newvd->vdev_path);
4520         newvd_isspare = newvd->vdev_isspare;
4521 
4522         /*
4523          * Mark newvd's DTL dirty in this txg.
4524          */
4525         vdev_dirty(tvd, VDD_DTL, newvd, txg);
4526 
4527         /*
4528          * Schedule the resilver to restart in the future. We do this to
4529          * ensure that dmu_sync-ed blocks have been stitched into the
4530          * respective datasets.
4531          */
4532         dsl_resilver_restart(spa->spa_dsl_pool, dtl_max_txg);
4533 
4534         /*
4535          * Commit the config
4536          */
4537         (void) spa_vdev_exit(spa, newrootvd, dtl_max_txg, 0);
4538 
4539         spa_history_log_internal(spa, "vdev attach", NULL,
4540             "%s vdev=%s %s vdev=%s",
4541             replacing && newvd_isspare ? "spare in" :
4542             replacing ? "replace" : "attach", newvdpath,
4543             replacing ? "for" : "to", oldvdpath);
4544 
4545         spa_strfree(oldvdpath);
4546         spa_strfree(newvdpath);
4547 
4548         if (spa->spa_bootfs)
4549                 spa_event_notify(spa, newvd, ESC_ZFS_BOOTFS_VDEV_ATTACH);
4550 
4551         return (0);
4552 }
4553 
4554 /*
4555  * Detach a device from a mirror or replacing vdev.
4556  *
4557  * If 'replace_done' is specified, only detach if the parent
4558  * is a replacing vdev.
4559  */
4560 int
4561 spa_vdev_detach(spa_t *spa, uint64_t guid, uint64_t pguid, int replace_done)
4562 {
4563         uint64_t txg;
4564         int error;
4565         vdev_t *rvd = spa->spa_root_vdev;
4566         vdev_t *vd, *pvd, *cvd, *tvd;
4567         boolean_t unspare = B_FALSE;
4568         uint64_t unspare_guid = 0;
4569         char *vdpath;
4570 
4571         ASSERT(spa_writeable(spa));
4572 
4573         txg = spa_vdev_enter(spa);
4574 
4575         vd = spa_lookup_by_guid(spa, guid, B_FALSE);
4576 
4577         if (vd == NULL)
4578                 return (spa_vdev_exit(spa, NULL, txg, ENODEV));
4579 
4580         if (!vd->vdev_ops->vdev_op_leaf)
4581                 return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
4582 
4583         pvd = vd->vdev_parent;
4584 
4585         /*
4586          * If the parent/child relationship is not as expected, don't do it.
4587          * Consider M(A,R(B,C)) -- that is, a mirror of A with a replacing
4588          * vdev that's replacing B with C.  The user's intent in replacing
4589          * is to go from M(A,B) to M(A,C).  If the user decides to cancel
4590          * the replace by detaching C, the expected behavior is to end up
4591          * M(A,B).  But suppose that right after deciding to detach C,
4592          * the replacement of B completes.  We would have M(A,C), and then
4593          * ask to detach C, which would leave us with just A -- not what
4594          * the user wanted.  To prevent this, we make sure that the
4595          * parent/child relationship hasn't changed -- in this example,
4596          * that C's parent is still the replacing vdev R.
4597          */
4598         if (pvd->vdev_guid != pguid && pguid != 0)
4599                 return (spa_vdev_exit(spa, NULL, txg, EBUSY));
4600 
4601         /*
4602          * Only 'replacing' or 'spare' vdevs can be replaced.
4603          */
4604         if (replace_done && pvd->vdev_ops != &vdev_replacing_ops &&
4605             pvd->vdev_ops != &vdev_spare_ops)
4606                 return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
4607 
4608         ASSERT(pvd->vdev_ops != &vdev_spare_ops ||
4609             spa_version(spa) >= SPA_VERSION_SPARES);
4610 
4611         /*
4612          * Only mirror, replacing, and spare vdevs support detach.
4613          */
4614         if (pvd->vdev_ops != &vdev_replacing_ops &&
4615             pvd->vdev_ops != &vdev_mirror_ops &&
4616             pvd->vdev_ops != &vdev_spare_ops)
4617                 return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
4618 
4619         /*
4620          * If this device has the only valid copy of some data,
4621          * we cannot safely detach it.
4622          */
4623         if (vdev_dtl_required(vd))
4624                 return (spa_vdev_exit(spa, NULL, txg, EBUSY));
4625 
4626         ASSERT(pvd->vdev_children >= 2);
4627 
4628         /*
4629          * If we are detaching the second disk from a replacing vdev, then
4630          * check to see if we changed the original vdev's path to have "/old"
4631          * at the end in spa_vdev_attach().  If so, undo that change now.
4632          */
4633         if (pvd->vdev_ops == &vdev_replacing_ops && vd->vdev_id > 0 &&
4634             vd->vdev_path != NULL) {
4635                 size_t len = strlen(vd->vdev_path);
4636 
4637                 for (int c = 0; c < pvd->vdev_children; c++) {
4638                         cvd = pvd->vdev_child[c];
4639 
4640                         if (cvd == vd || cvd->vdev_path == NULL)
4641                                 continue;
4642 
4643                         if (strncmp(cvd->vdev_path, vd->vdev_path, len) == 0 &&
4644                             strcmp(cvd->vdev_path + len, "/old") == 0) {
4645                                 spa_strfree(cvd->vdev_path);
4646                                 cvd->vdev_path = spa_strdup(vd->vdev_path);
4647                                 break;
4648                         }
4649                 }
4650         }
4651 
4652         /*
4653          * If we are detaching the original disk from a spare, then it implies
4654          * that the spare should become a real disk, and be removed from the
4655          * active spare list for the pool.
4656          */
4657         if (pvd->vdev_ops == &vdev_spare_ops &&
4658             vd->vdev_id == 0 &&
4659             pvd->vdev_child[pvd->vdev_children - 1]->vdev_isspare)
4660                 unspare = B_TRUE;
4661 
4662         /*
4663          * Erase the disk labels so the disk can be used for other things.
4664          * This must be done after all other error cases are handled,
4665          * but before we disembowel vd (so we can still do I/O to it).
4666          * But if we can't do it, don't treat the error as fatal --
4667          * it may be that the unwritability of the disk is the reason
4668          * it's being detached!
4669          */
4670         error = vdev_label_init(vd, 0, VDEV_LABEL_REMOVE);
4671 
4672         /*
4673          * Remove vd from its parent and compact the parent's children.
4674          */
4675         vdev_remove_child(pvd, vd);
4676         vdev_compact_children(pvd);
4677 
4678         /*
4679          * Remember one of the remaining children so we can get tvd below.
4680          */
4681         cvd = pvd->vdev_child[pvd->vdev_children - 1];
4682 
4683         /*
4684          * If we need to remove the remaining child from the list of hot spares,
4685          * do it now, marking the vdev as no longer a spare in the process.
4686          * We must do this before vdev_remove_parent(), because that can
4687          * change the GUID if it creates a new toplevel GUID.  For a similar
4688          * reason, we must remove the spare now, in the same txg as the detach;
4689          * otherwise someone could attach a new sibling, change the GUID, and
4690          * the subsequent attempt to spa_vdev_remove(unspare_guid) would fail.
4691          */
4692         if (unspare) {
4693                 ASSERT(cvd->vdev_isspare);
4694                 spa_spare_remove(cvd);
4695                 unspare_guid = cvd->vdev_guid;
4696                 (void) spa_vdev_remove(spa, unspare_guid, B_TRUE);
4697                 cvd->vdev_unspare = B_TRUE;
4698         }
4699 
4700         /*
4701          * If the parent mirror/replacing vdev only has one child,
4702          * the parent is no longer needed.  Remove it from the tree.
4703          */
4704         if (pvd->vdev_children == 1) {
4705                 if (pvd->vdev_ops == &vdev_spare_ops)
4706                         cvd->vdev_unspare = B_FALSE;
4707                 vdev_remove_parent(cvd);
4708         }
4709 
4710 
4711         /*
4712          * We don't set tvd until now because the parent we just removed
4713          * may have been the previous top-level vdev.
4714          */
4715         tvd = cvd->vdev_top;
4716         ASSERT(tvd->vdev_parent == rvd);
4717 
4718         /*
4719          * Reevaluate the parent vdev state.
4720          */
4721         vdev_propagate_state(cvd);
4722 
4723         /*
4724          * If the 'autoexpand' property is set on the pool then automatically
4725          * try to expand the size of the pool. For example if the device we
4726          * just detached was smaller than the others, it may be possible to
4727          * add metaslabs (i.e. grow the pool). We need to reopen the vdev
4728          * first so that we can obtain the updated sizes of the leaf vdevs.
4729          */
4730         if (spa->spa_autoexpand) {
4731                 vdev_reopen(tvd);
4732                 vdev_expand(tvd, txg);
4733         }
4734 
4735         vdev_config_dirty(tvd);
4736 
4737         /*
4738          * Mark vd's DTL as dirty in this txg.  vdev_dtl_sync() will see that
4739          * vd->vdev_detached is set and free vd's DTL object in syncing context.
4740          * But first make sure we're not on any *other* txg's DTL list, to
4741          * prevent vd from being accessed after it's freed.
4742          */
4743         vdpath = spa_strdup(vd->vdev_path);
4744         for (int t = 0; t < TXG_SIZE; t++)
4745                 (void) txg_list_remove_this(&tvd->vdev_dtl_list, vd, t);
4746         vd->vdev_detached = B_TRUE;
4747         vdev_dirty(tvd, VDD_DTL, vd, txg);
4748 
4749         spa_event_notify(spa, vd, ESC_ZFS_VDEV_REMOVE);
4750 
4751         /* hang on to the spa before we release the lock */
4752         spa_open_ref(spa, FTAG);
4753 
4754         error = spa_vdev_exit(spa, vd, txg, 0);
4755 
4756         spa_history_log_internal(spa, "detach", NULL,
4757             "vdev=%s", vdpath);
4758         spa_strfree(vdpath);
4759 
4760         /*
4761          * If this was the removal of the original device in a hot spare vdev,
4762          * then we want to go through and remove the device from the hot spare
4763          * list of every other pool.
4764          */
4765         if (unspare) {
4766                 spa_t *altspa = NULL;
4767 
4768                 mutex_enter(&spa_namespace_lock);
4769                 while ((altspa = spa_next(altspa)) != NULL) {
4770                         if (altspa->spa_state != POOL_STATE_ACTIVE ||
4771                             altspa == spa)
4772                                 continue;
4773 
4774                         spa_open_ref(altspa, FTAG);
4775                         mutex_exit(&spa_namespace_lock);
4776                         (void) spa_vdev_remove(altspa, unspare_guid, B_TRUE);
4777                         mutex_enter(&spa_namespace_lock);
4778                         spa_close(altspa, FTAG);
4779                 }
4780                 mutex_exit(&spa_namespace_lock);
4781 
4782                 /* search the rest of the vdevs for spares to remove */
4783                 spa_vdev_resilver_done(spa);
4784         }
4785 
4786         /* all done with the spa; OK to release */
4787         mutex_enter(&spa_namespace_lock);
4788         spa_close(spa, FTAG);
4789         mutex_exit(&spa_namespace_lock);
4790 
4791         return (error);
4792 }
4793 
4794 /*
4795  * Split a set of devices from their mirrors, and create a new pool from them.
4796  */
4797 int
4798 spa_vdev_split_mirror(spa_t *spa, char *newname, nvlist_t *config,
4799     nvlist_t *props, boolean_t exp)
4800 {
4801         int error = 0;
4802         uint64_t txg, *glist;
4803         spa_t *newspa;
4804         uint_t c, children, lastlog;
4805         nvlist_t **child, *nvl, *tmp;
4806         dmu_tx_t *tx;
4807         char *altroot = NULL;
4808         vdev_t *rvd, **vml = NULL;                      /* vdev modify list */
4809         boolean_t activate_slog;
4810 
4811         ASSERT(spa_writeable(spa));
4812 
4813         txg = spa_vdev_enter(spa);
4814 
4815         /* clear the log and flush everything up to now */
4816         activate_slog = spa_passivate_log(spa);
4817         (void) spa_vdev_config_exit(spa, NULL, txg, 0, FTAG);
4818         error = spa_offline_log(spa);
4819         txg = spa_vdev_config_enter(spa);
4820 
4821         if (activate_slog)
4822                 spa_activate_log(spa);
4823 
4824         if (error != 0)
4825                 return (spa_vdev_exit(spa, NULL, txg, error));
4826 
4827         /* check new spa name before going any further */
4828         if (spa_lookup(newname) != NULL)
4829                 return (spa_vdev_exit(spa, NULL, txg, EEXIST));
4830 
4831         /*
4832          * scan through all the children to ensure they're all mirrors
4833          */
4834         if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nvl) != 0 ||
4835             nvlist_lookup_nvlist_array(nvl, ZPOOL_CONFIG_CHILDREN, &child,
4836             &children) != 0)
4837                 return (spa_vdev_exit(spa, NULL, txg, EINVAL));
4838 
4839         /* first, check to ensure we've got the right child count */
4840         rvd = spa->spa_root_vdev;
4841         lastlog = 0;
4842         for (c = 0; c < rvd->vdev_children; c++) {
4843                 vdev_t *vd = rvd->vdev_child[c];
4844 
4845                 /* don't count the holes & logs as children */
4846                 if (vd->vdev_islog || vd->vdev_ishole) {
4847                         if (lastlog == 0)
4848                                 lastlog = c;
4849                         continue;
4850                 }
4851 
4852                 lastlog = 0;
4853         }
4854         if (children != (lastlog != 0 ? lastlog : rvd->vdev_children))
4855                 return (spa_vdev_exit(spa, NULL, txg, EINVAL));
4856 
4857         /* next, ensure no spare or cache devices are part of the split */
4858         if (nvlist_lookup_nvlist(nvl, ZPOOL_CONFIG_SPARES, &tmp) == 0 ||
4859             nvlist_lookup_nvlist(nvl, ZPOOL_CONFIG_L2CACHE, &tmp) == 0)
4860                 return (spa_vdev_exit(spa, NULL, txg, EINVAL));
4861 
4862         vml = kmem_zalloc(children * sizeof (vdev_t *), KM_SLEEP);
4863         glist = kmem_zalloc(children * sizeof (uint64_t), KM_SLEEP);
4864 
4865         /* then, loop over each vdev and validate it */
4866         for (c = 0; c < children; c++) {
4867                 uint64_t is_hole = 0;
4868 
4869                 (void) nvlist_lookup_uint64(child[c], ZPOOL_CONFIG_IS_HOLE,
4870                     &is_hole);
4871 
4872                 if (is_hole != 0) {
4873                         if (spa->spa_root_vdev->vdev_child[c]->vdev_ishole ||
4874                             spa->spa_root_vdev->vdev_child[c]->vdev_islog) {
4875                                 continue;
4876                         } else {
4877                                 error = SET_ERROR(EINVAL);
4878                                 break;
4879                         }
4880                 }
4881 
4882                 /* which disk is going to be split? */
4883                 if (nvlist_lookup_uint64(child[c], ZPOOL_CONFIG_GUID,
4884                     &glist[c]) != 0) {
4885                         error = SET_ERROR(EINVAL);
4886                         break;
4887                 }
4888 
4889                 /* look it up in the spa */
4890                 vml[c] = spa_lookup_by_guid(spa, glist[c], B_FALSE);
4891                 if (vml[c] == NULL) {
4892                         error = SET_ERROR(ENODEV);
4893                         break;
4894                 }
4895 
4896                 /* make sure there's nothing stopping the split */
4897                 if (vml[c]->vdev_parent->vdev_ops != &vdev_mirror_ops ||
4898                     vml[c]->vdev_islog ||
4899                     vml[c]->vdev_ishole ||
4900                     vml[c]->vdev_isspare ||
4901                     vml[c]->vdev_isl2cache ||
4902                     !vdev_writeable(vml[c]) ||
4903                     vml[c]->vdev_children != 0 ||
4904                     vml[c]->vdev_state != VDEV_STATE_HEALTHY ||
4905                     c != spa->spa_root_vdev->vdev_child[c]->vdev_id) {
4906                         error = SET_ERROR(EINVAL);
4907                         break;
4908                 }
4909 
4910                 if (vdev_dtl_required(vml[c])) {
4911                         error = SET_ERROR(EBUSY);
4912                         break;
4913                 }
4914 
4915                 /* we need certain info from the top level */
4916                 VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_METASLAB_ARRAY,
4917                     vml[c]->vdev_top->vdev_ms_array) == 0);
4918                 VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_METASLAB_SHIFT,
4919                     vml[c]->vdev_top->vdev_ms_shift) == 0);
4920                 VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_ASIZE,
4921                     vml[c]->vdev_top->vdev_asize) == 0);
4922                 VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_ASHIFT,
4923                     vml[c]->vdev_top->vdev_ashift) == 0);
4924         }
4925 
4926         if (error != 0) {
4927                 kmem_free(vml, children * sizeof (vdev_t *));
4928                 kmem_free(glist, children * sizeof (uint64_t));
4929                 return (spa_vdev_exit(spa, NULL, txg, error));
4930         }
4931 
4932         /* stop writers from using the disks */
4933         for (c = 0; c < children; c++) {
4934                 if (vml[c] != NULL)
4935                         vml[c]->vdev_offline = B_TRUE;
4936         }
4937         vdev_reopen(spa->spa_root_vdev);
4938 
4939         /*
4940          * Temporarily record the splitting vdevs in the spa config.  This
4941          * will disappear once the config is regenerated.
4942          */
4943         VERIFY(nvlist_alloc(&nvl, NV_UNIQUE_NAME, KM_SLEEP) == 0);
4944         VERIFY(nvlist_add_uint64_array(nvl, ZPOOL_CONFIG_SPLIT_LIST,
4945             glist, children) == 0);
4946         kmem_free(glist, children * sizeof (uint64_t));
4947 
4948         mutex_enter(&spa->spa_props_lock);
4949         VERIFY(nvlist_add_nvlist(spa->spa_config, ZPOOL_CONFIG_SPLIT,
4950             nvl) == 0);
4951         mutex_exit(&spa->spa_props_lock);
4952         spa->spa_config_splitting = nvl;
4953         vdev_config_dirty(spa->spa_root_vdev);
4954 
4955         /* configure and create the new pool */
4956         VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, newname) == 0);
4957         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
4958             exp ? POOL_STATE_EXPORTED : POOL_STATE_ACTIVE) == 0);
4959         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION,
4960             spa_version(spa)) == 0);
4961         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG,
4962             spa->spa_config_txg) == 0);
4963         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID,
4964             spa_generate_guid(NULL)) == 0);
4965         (void) nvlist_lookup_string(props,
4966             zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
4967 
4968         /* add the new pool to the namespace */
4969         newspa = spa_add(newname, config, altroot);
4970         newspa->spa_config_txg = spa->spa_config_txg;
4971         spa_set_log_state(newspa, SPA_LOG_CLEAR);
4972 
4973         /* release the spa config lock, retaining the namespace lock */
4974         spa_vdev_config_exit(spa, NULL, txg, 0, FTAG);
4975 
4976         if (zio_injection_enabled)
4977                 zio_handle_panic_injection(spa, FTAG, 1);
4978 
4979         spa_activate(newspa, spa_mode_global);
4980         spa_async_suspend(newspa);
4981 
4982         /* create the new pool from the disks of the original pool */
4983         error = spa_load(newspa, SPA_LOAD_IMPORT, SPA_IMPORT_ASSEMBLE, B_TRUE);
4984         if (error)
4985                 goto out;
4986 
4987         /* if that worked, generate a real config for the new pool */
4988         if (newspa->spa_root_vdev != NULL) {
4989                 VERIFY(nvlist_alloc(&newspa->spa_config_splitting,
4990                     NV_UNIQUE_NAME, KM_SLEEP) == 0);
4991                 VERIFY(nvlist_add_uint64(newspa->spa_config_splitting,
4992                     ZPOOL_CONFIG_SPLIT_GUID, spa_guid(spa)) == 0);
4993                 spa_config_set(newspa, spa_config_generate(newspa, NULL, -1ULL,
4994                     B_TRUE));
4995         }
4996 
4997         /* set the props */
4998         if (props != NULL) {
4999                 spa_configfile_set(newspa, props, B_FALSE);
5000                 error = spa_prop_set(newspa, props);
5001                 if (error)
5002                         goto out;
5003         }
5004 
5005         /* flush everything */
5006         txg = spa_vdev_config_enter(newspa);
5007         vdev_config_dirty(newspa->spa_root_vdev);
5008         (void) spa_vdev_config_exit(newspa, NULL, txg, 0, FTAG);
5009 
5010         if (zio_injection_enabled)
5011                 zio_handle_panic_injection(spa, FTAG, 2);
5012 
5013         spa_async_resume(newspa);
5014 
5015         /* finally, update the original pool's config */
5016         txg = spa_vdev_config_enter(spa);
5017         tx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir);
5018         error = dmu_tx_assign(tx, TXG_WAIT);
5019         if (error != 0)
5020                 dmu_tx_abort(tx);
5021         for (c = 0; c < children; c++) {
5022                 if (vml[c] != NULL) {
5023                         vdev_split(vml[c]);
5024                         if (error == 0)
5025                                 spa_history_log_internal(spa, "detach", tx,
5026                                     "vdev=%s", vml[c]->vdev_path);
5027                         vdev_free(vml[c]);
5028                 }
5029         }
5030         vdev_config_dirty(spa->spa_root_vdev);
5031         spa->spa_config_splitting = NULL;
5032         nvlist_free(nvl);
5033         if (error == 0)
5034                 dmu_tx_commit(tx);
5035         (void) spa_vdev_exit(spa, NULL, txg, 0);
5036 
5037         if (zio_injection_enabled)
5038                 zio_handle_panic_injection(spa, FTAG, 3);
5039 
5040         /* split is complete; log a history record */
5041         spa_history_log_internal(newspa, "split", NULL,
5042             "from pool %s", spa_name(spa));
5043 
5044         kmem_free(vml, children * sizeof (vdev_t *));
5045 
5046         /* if we're not going to mount the filesystems in userland, export */
5047         if (exp)
5048                 error = spa_export_common(newname, POOL_STATE_EXPORTED, NULL,
5049                     B_FALSE, B_FALSE);
5050 
5051         return (error);
5052 
5053 out:
5054         spa_unload(newspa);
5055         spa_deactivate(newspa);
5056         spa_remove(newspa);
5057 
5058         txg = spa_vdev_config_enter(spa);
5059 
5060         /* re-online all offlined disks */
5061         for (c = 0; c < children; c++) {
5062                 if (vml[c] != NULL)
5063                         vml[c]->vdev_offline = B_FALSE;
5064         }
5065         vdev_reopen(spa->spa_root_vdev);
5066 
5067         nvlist_free(spa->spa_config_splitting);
5068         spa->spa_config_splitting = NULL;
5069         (void) spa_vdev_exit(spa, NULL, txg, error);
5070 
5071         kmem_free(vml, children * sizeof (vdev_t *));
5072         return (error);
5073 }
5074 
5075 static nvlist_t *
5076 spa_nvlist_lookup_by_guid(nvlist_t **nvpp, int count, uint64_t target_guid)
5077 {
5078         for (int i = 0; i < count; i++) {
5079                 uint64_t guid;
5080 
5081                 VERIFY(nvlist_lookup_uint64(nvpp[i], ZPOOL_CONFIG_GUID,
5082                     &guid) == 0);
5083 
5084                 if (guid == target_guid)
5085                         return (nvpp[i]);
5086         }
5087 
5088         return (NULL);
5089 }
5090 
5091 static void
5092 spa_vdev_remove_aux(nvlist_t *config, char *name, nvlist_t **dev, int count,
5093         nvlist_t *dev_to_remove)
5094 {
5095         nvlist_t **newdev = NULL;
5096 
5097         if (count > 1)
5098                 newdev = kmem_alloc((count - 1) * sizeof (void *), KM_SLEEP);
5099 
5100         for (int i = 0, j = 0; i < count; i++) {
5101                 if (dev[i] == dev_to_remove)
5102                         continue;
5103                 VERIFY(nvlist_dup(dev[i], &newdev[j++], KM_SLEEP) == 0);
5104         }
5105 
5106         VERIFY(nvlist_remove(config, name, DATA_TYPE_NVLIST_ARRAY) == 0);
5107         VERIFY(nvlist_add_nvlist_array(config, name, newdev, count - 1) == 0);
5108 
5109         for (int i = 0; i < count - 1; i++)
5110                 nvlist_free(newdev[i]);
5111 
5112         if (count > 1)
5113                 kmem_free(newdev, (count - 1) * sizeof (void *));
5114 }
5115 
5116 /*
5117  * Evacuate the device.
5118  */
5119 static int
5120 spa_vdev_remove_evacuate(spa_t *spa, vdev_t *vd)
5121 {
5122         uint64_t txg;
5123         int error = 0;
5124 
5125         ASSERT(MUTEX_HELD(&spa_namespace_lock));
5126         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == 0);
5127         ASSERT(vd == vd->vdev_top);
5128 
5129         /*
5130          * Evacuate the device.  We don't hold the config lock as writer
5131          * since we need to do I/O but we do keep the
5132          * spa_namespace_lock held.  Once this completes the device
5133          * should no longer have any blocks allocated on it.
5134          */
5135         if (vd->vdev_islog) {
5136                 if (vd->vdev_stat.vs_alloc != 0)
5137                         error = spa_offline_log(spa);
5138         } else {
5139                 error = SET_ERROR(ENOTSUP);
5140         }
5141 
5142         if (error)
5143                 return (error);
5144 
5145         /*
5146          * The evacuation succeeded.  Remove any remaining MOS metadata
5147          * associated with this vdev, and wait for these changes to sync.
5148          */
5149         ASSERT0(vd->vdev_stat.vs_alloc);
5150         txg = spa_vdev_config_enter(spa);
5151         vd->vdev_removing = B_TRUE;
5152         vdev_dirty_leaves(vd, VDD_DTL, txg);
5153         vdev_config_dirty(vd);
5154         spa_vdev_config_exit(spa, NULL, txg, 0, FTAG);
5155 
5156         return (0);
5157 }
5158 
5159 /*
5160  * Complete the removal by cleaning up the namespace.
5161  */
5162 static void
5163 spa_vdev_remove_from_namespace(spa_t *spa, vdev_t *vd)
5164 {
5165         vdev_t *rvd = spa->spa_root_vdev;
5166         uint64_t id = vd->vdev_id;
5167         boolean_t last_vdev = (id == (rvd->vdev_children - 1));
5168 
5169         ASSERT(MUTEX_HELD(&spa_namespace_lock));
5170         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
5171         ASSERT(vd == vd->vdev_top);
5172 
5173         /*
5174          * Only remove any devices which are empty.
5175          */
5176         if (vd->vdev_stat.vs_alloc != 0)
5177                 return;
5178 
5179         (void) vdev_label_init(vd, 0, VDEV_LABEL_REMOVE);
5180 
5181         if (list_link_active(&vd->vdev_state_dirty_node))
5182                 vdev_state_clean(vd);
5183         if (list_link_active(&vd->vdev_config_dirty_node))
5184                 vdev_config_clean(vd);
5185 
5186         vdev_free(vd);
5187 
5188         if (last_vdev) {
5189                 vdev_compact_children(rvd);
5190         } else {
5191                 vd = vdev_alloc_common(spa, id, 0, &vdev_hole_ops);
5192                 vdev_add_child(rvd, vd);
5193         }
5194         vdev_config_dirty(rvd);
5195 
5196         /*
5197          * Reassess the health of our root vdev.
5198          */
5199         vdev_reopen(rvd);
5200 }
5201 
5202 /*
5203  * Remove a device from the pool -
5204  *
5205  * Removing a device from the vdev namespace requires several steps
5206  * and can take a significant amount of time.  As a result we use
5207  * the spa_vdev_config_[enter/exit] functions which allow us to
5208  * grab and release the spa_config_lock while still holding the namespace
5209  * lock.  During each step the configuration is synced out.
5210  *
5211  * Currently, this supports removing only hot spares, slogs, and level 2 ARC
5212  * devices.
5213  */
5214 int
5215 spa_vdev_remove(spa_t *spa, uint64_t guid, boolean_t unspare)
5216 {
5217         vdev_t *vd;
5218         metaslab_group_t *mg;
5219         nvlist_t **spares, **l2cache, *nv;
5220         uint64_t txg = 0;
5221         uint_t nspares, nl2cache;
5222         int error = 0;
5223         boolean_t locked = MUTEX_HELD(&spa_namespace_lock);
5224 
5225         ASSERT(spa_writeable(spa));
5226 
5227         if (!locked)
5228                 txg = spa_vdev_enter(spa);
5229 
5230         vd = spa_lookup_by_guid(spa, guid, B_FALSE);
5231 
5232         if (spa->spa_spares.sav_vdevs != NULL &&
5233             nvlist_lookup_nvlist_array(spa->spa_spares.sav_config,
5234             ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0 &&
5235             (nv = spa_nvlist_lookup_by_guid(spares, nspares, guid)) != NULL) {
5236                 /*
5237                  * Only remove the hot spare if it's not currently in use
5238                  * in this pool.
5239                  */
5240                 if (vd == NULL || unspare) {
5241                         spa_vdev_remove_aux(spa->spa_spares.sav_config,
5242                             ZPOOL_CONFIG_SPARES, spares, nspares, nv);
5243                         spa_load_spares(spa);
5244                         spa->spa_spares.sav_sync = B_TRUE;
5245                 } else {
5246                         error = SET_ERROR(EBUSY);
5247                 }
5248         } else if (spa->spa_l2cache.sav_vdevs != NULL &&
5249             nvlist_lookup_nvlist_array(spa->spa_l2cache.sav_config,
5250             ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0 &&
5251             (nv = spa_nvlist_lookup_by_guid(l2cache, nl2cache, guid)) != NULL) {
5252                 /*
5253                  * Cache devices can always be removed.
5254                  */
5255                 spa_vdev_remove_aux(spa->spa_l2cache.sav_config,
5256                     ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache, nv);
5257                 spa_load_l2cache(spa);
5258                 spa->spa_l2cache.sav_sync = B_TRUE;
5259         } else if (vd != NULL && vd->vdev_islog) {
5260                 ASSERT(!locked);
5261                 ASSERT(vd == vd->vdev_top);
5262 
5263                 /*
5264                  * XXX - Once we have bp-rewrite this should
5265                  * become the common case.
5266                  */
5267 
5268                 mg = vd->vdev_mg;
5269 
5270                 /*
5271                  * Stop allocating from this vdev.
5272                  */
5273                 metaslab_group_passivate(mg);
5274 
5275                 /*
5276                  * Wait for the youngest allocations and frees to sync,
5277                  * and then wait for the deferral of those frees to finish.
5278                  */
5279                 spa_vdev_config_exit(spa, NULL,
5280                     txg + TXG_CONCURRENT_STATES + TXG_DEFER_SIZE, 0, FTAG);
5281 
5282                 /*
5283                  * Attempt to evacuate the vdev.
5284                  */
5285                 error = spa_vdev_remove_evacuate(spa, vd);
5286 
5287                 txg = spa_vdev_config_enter(spa);
5288 
5289                 /*
5290                  * If we couldn't evacuate the vdev, unwind.
5291                  */
5292                 if (error) {
5293                         metaslab_group_activate(mg);
5294                         return (spa_vdev_exit(spa, NULL, txg, error));
5295                 }
5296 
5297                 /*
5298                  * Clean up the vdev namespace.
5299                  */
5300                 spa_vdev_remove_from_namespace(spa, vd);
5301 
5302         } else if (vd != NULL) {
5303                 /*
5304                  * Normal vdevs cannot be removed (yet).
5305                  */
5306                 error = SET_ERROR(ENOTSUP);
5307         } else {
5308                 /*
5309                  * There is no vdev of any kind with the specified guid.
5310                  */
5311                 error = SET_ERROR(ENOENT);
5312         }
5313 
5314         if (!locked)
5315                 return (spa_vdev_exit(spa, NULL, txg, error));
5316 
5317         return (error);
5318 }
5319 
5320 /*
5321  * Find any device that's done replacing, or a vdev marked 'unspare' that's
5322  * currently spared, so we can detach it.
5323  */
5324 static vdev_t *
5325 spa_vdev_resilver_done_hunt(vdev_t *vd)
5326 {
5327         vdev_t *newvd, *oldvd;
5328 
5329         for (int c = 0; c < vd->vdev_children; c++) {
5330                 oldvd = spa_vdev_resilver_done_hunt(vd->vdev_child[c]);
5331                 if (oldvd != NULL)
5332                         return (oldvd);
5333         }
5334 
5335         /*
5336          * Check for a completed replacement.  We always consider the first
5337          * vdev in the list to be the oldest vdev, and the last one to be
5338          * the newest (see spa_vdev_attach() for how that works).  In
5339          * the case where the newest vdev is faulted, we will not automatically
5340          * remove it after a resilver completes.  This is OK as it will require
5341          * user intervention to determine which disk the admin wishes to keep.
5342          */
5343         if (vd->vdev_ops == &vdev_replacing_ops) {
5344                 ASSERT(vd->vdev_children > 1);
5345 
5346                 newvd = vd->vdev_child[vd->vdev_children - 1];
5347                 oldvd = vd->vdev_child[0];
5348 
5349                 if (vdev_dtl_empty(newvd, DTL_MISSING) &&
5350                     vdev_dtl_empty(newvd, DTL_OUTAGE) &&
5351                     !vdev_dtl_required(oldvd))
5352                         return (oldvd);
5353         }
5354 
5355         /*
5356          * Check for a completed resilver with the 'unspare' flag set.
5357          */
5358         if (vd->vdev_ops == &vdev_spare_ops) {
5359                 vdev_t *first = vd->vdev_child[0];
5360                 vdev_t *last = vd->vdev_child[vd->vdev_children - 1];
5361 
5362                 if (last->vdev_unspare) {
5363                         oldvd = first;
5364                         newvd = last;
5365                 } else if (first->vdev_unspare) {
5366                         oldvd = last;
5367                         newvd = first;
5368                 } else {
5369                         oldvd = NULL;
5370                 }
5371 
5372                 if (oldvd != NULL &&
5373                     vdev_dtl_empty(newvd, DTL_MISSING) &&
5374                     vdev_dtl_empty(newvd, DTL_OUTAGE) &&
5375                     !vdev_dtl_required(oldvd))
5376                         return (oldvd);
5377 
5378                 /*
5379                  * If there are more than two spares attached to a disk,
5380                  * and those spares are not required, then we want to
5381                  * attempt to free them up now so that they can be used
5382                  * by other pools.  Once we're back down to a single
5383                  * disk+spare, we stop removing them.
5384                  */
5385                 if (vd->vdev_children > 2) {
5386                         newvd = vd->vdev_child[1];
5387 
5388                         if (newvd->vdev_isspare && last->vdev_isspare &&
5389                             vdev_dtl_empty(last, DTL_MISSING) &&
5390                             vdev_dtl_empty(last, DTL_OUTAGE) &&
5391                             !vdev_dtl_required(newvd))
5392                                 return (newvd);
5393                 }
5394         }
5395 
5396         return (NULL);
5397 }
5398 
5399 static void
5400 spa_vdev_resilver_done(spa_t *spa)
5401 {
5402         vdev_t *vd, *pvd, *ppvd;
5403         uint64_t guid, sguid, pguid, ppguid;
5404 
5405         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
5406 
5407         while ((vd = spa_vdev_resilver_done_hunt(spa->spa_root_vdev)) != NULL) {
5408                 pvd = vd->vdev_parent;
5409                 ppvd = pvd->vdev_parent;
5410                 guid = vd->vdev_guid;
5411                 pguid = pvd->vdev_guid;
5412                 ppguid = ppvd->vdev_guid;
5413                 sguid = 0;
5414                 /*
5415                  * If we have just finished replacing a hot spared device, then
5416                  * we need to detach the parent's first child (the original hot
5417                  * spare) as well.
5418                  */
5419                 if (ppvd->vdev_ops == &vdev_spare_ops && pvd->vdev_id == 0 &&
5420                     ppvd->vdev_children == 2) {
5421                         ASSERT(pvd->vdev_ops == &vdev_replacing_ops);
5422                         sguid = ppvd->vdev_child[1]->vdev_guid;
5423                 }
5424                 ASSERT(vd->vdev_resilver_txg == 0 || !vdev_dtl_required(vd));
5425 
5426                 spa_config_exit(spa, SCL_ALL, FTAG);
5427                 if (spa_vdev_detach(spa, guid, pguid, B_TRUE) != 0)
5428                         return;
5429                 if (sguid && spa_vdev_detach(spa, sguid, ppguid, B_TRUE) != 0)
5430                         return;
5431                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
5432         }
5433 
5434         spa_config_exit(spa, SCL_ALL, FTAG);
5435 }
5436 
5437 /*
5438  * Update the stored path or FRU for this vdev.
5439  */
5440 int
5441 spa_vdev_set_common(spa_t *spa, uint64_t guid, const char *value,
5442     boolean_t ispath)
5443 {
5444         vdev_t *vd;
5445         boolean_t sync = B_FALSE;
5446 
5447         ASSERT(spa_writeable(spa));
5448 
5449         spa_vdev_state_enter(spa, SCL_ALL);
5450 
5451         if ((vd = spa_lookup_by_guid(spa, guid, B_TRUE)) == NULL)
5452                 return (spa_vdev_state_exit(spa, NULL, ENOENT));
5453 
5454         if (!vd->vdev_ops->vdev_op_leaf)
5455                 return (spa_vdev_state_exit(spa, NULL, ENOTSUP));
5456 
5457         if (ispath) {
5458                 if (strcmp(value, vd->vdev_path) != 0) {
5459                         spa_strfree(vd->vdev_path);
5460                         vd->vdev_path = spa_strdup(value);
5461                         sync = B_TRUE;
5462                 }
5463         } else {
5464                 if (vd->vdev_fru == NULL) {
5465                         vd->vdev_fru = spa_strdup(value);
5466                         sync = B_TRUE;
5467                 } else if (strcmp(value, vd->vdev_fru) != 0) {
5468                         spa_strfree(vd->vdev_fru);
5469                         vd->vdev_fru = spa_strdup(value);
5470                         sync = B_TRUE;
5471                 }
5472         }
5473 
5474         return (spa_vdev_state_exit(spa, sync ? vd : NULL, 0));
5475 }
5476 
5477 int
5478 spa_vdev_setpath(spa_t *spa, uint64_t guid, const char *newpath)
5479 {
5480         return (spa_vdev_set_common(spa, guid, newpath, B_TRUE));
5481 }
5482 
5483 int
5484 spa_vdev_setfru(spa_t *spa, uint64_t guid, const char *newfru)
5485 {
5486         return (spa_vdev_set_common(spa, guid, newfru, B_FALSE));
5487 }
5488 
5489 /*
5490  * ==========================================================================
5491  * SPA Scanning
5492  * ==========================================================================
5493  */
5494 
5495 int
5496 spa_scan_stop(spa_t *spa)
5497 {
5498         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == 0);
5499         if (dsl_scan_resilvering(spa->spa_dsl_pool))
5500                 return (SET_ERROR(EBUSY));
5501         return (dsl_scan_cancel(spa->spa_dsl_pool));
5502 }
5503 
5504 int
5505 spa_scan(spa_t *spa, pool_scan_func_t func)
5506 {
5507         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == 0);
5508 
5509         if (func >= POOL_SCAN_FUNCS || func == POOL_SCAN_NONE)
5510                 return (SET_ERROR(ENOTSUP));
5511 
5512         /*
5513          * If a resilver was requested, but there is no DTL on a
5514          * writeable leaf device, we have nothing to do.
5515          */
5516         if (func == POOL_SCAN_RESILVER &&
5517             !vdev_resilver_needed(spa->spa_root_vdev, NULL, NULL)) {
5518                 spa_async_request(spa, SPA_ASYNC_RESILVER_DONE);
5519                 return (0);
5520         }
5521 
5522         return (dsl_scan(spa->spa_dsl_pool, func));
5523 }
5524 
5525 /*
5526  * ==========================================================================
5527  * SPA async task processing
5528  * ==========================================================================
5529  */
5530 
5531 static void
5532 spa_async_remove(spa_t *spa, vdev_t *vd)
5533 {
5534         if (vd->vdev_remove_wanted) {
5535                 vd->vdev_remove_wanted = B_FALSE;
5536                 vd->vdev_delayed_close = B_FALSE;
5537                 vdev_set_state(vd, B_FALSE, VDEV_STATE_REMOVED, VDEV_AUX_NONE);
5538 
5539                 /*
5540                  * We want to clear the stats, but we don't want to do a full
5541                  * vdev_clear() as that will cause us to throw away
5542                  * degraded/faulted state as well as attempt to reopen the
5543                  * device, all of which is a waste.
5544                  */
5545                 vd->vdev_stat.vs_read_errors = 0;
5546                 vd->vdev_stat.vs_write_errors = 0;
5547                 vd->vdev_stat.vs_checksum_errors = 0;
5548 
5549                 vdev_state_dirty(vd->vdev_top);
5550         }
5551 
5552         for (int c = 0; c < vd->vdev_children; c++)
5553                 spa_async_remove(spa, vd->vdev_child[c]);
5554 }
5555 
5556 static void
5557 spa_async_probe(spa_t *spa, vdev_t *vd)
5558 {
5559         if (vd->vdev_probe_wanted) {
5560                 vd->vdev_probe_wanted = B_FALSE;
5561                 vdev_reopen(vd);        /* vdev_open() does the actual probe */
5562         }
5563 
5564         for (int c = 0; c < vd->vdev_children; c++)
5565                 spa_async_probe(spa, vd->vdev_child[c]);
5566 }
5567 
5568 static void
5569 spa_async_autoexpand(spa_t *spa, vdev_t *vd)
5570 {
5571         sysevent_id_t eid;
5572         nvlist_t *attr;
5573         char *physpath;
5574 
5575         if (!spa->spa_autoexpand)
5576                 return;
5577 
5578         for (int c = 0; c < vd->vdev_children; c++) {
5579                 vdev_t *cvd = vd->vdev_child[c];
5580                 spa_async_autoexpand(spa, cvd);
5581         }
5582 
5583         if (!vd->vdev_ops->vdev_op_leaf || vd->vdev_physpath == NULL)
5584                 return;
5585 
5586         physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
5587         (void) snprintf(physpath, MAXPATHLEN, "/devices%s", vd->vdev_physpath);
5588 
5589         VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
5590         VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
5591 
5592         (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
5593             ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
5594 
5595         nvlist_free(attr);
5596         kmem_free(physpath, MAXPATHLEN);
5597 }
5598 
5599 static void
5600 spa_async_thread(spa_t *spa)
5601 {
5602         int tasks;
5603 
5604         ASSERT(spa->spa_sync_on);
5605 
5606         mutex_enter(&spa->spa_async_lock);
5607         tasks = spa->spa_async_tasks;
5608         spa->spa_async_tasks = 0;
5609         mutex_exit(&spa->spa_async_lock);
5610 
5611         /*
5612          * See if the config needs to be updated.
5613          */
5614         if (tasks & SPA_ASYNC_CONFIG_UPDATE) {
5615                 uint64_t old_space, new_space;
5616 
5617                 mutex_enter(&spa_namespace_lock);
5618                 old_space = metaslab_class_get_space(spa_normal_class(spa));
5619                 spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
5620                 new_space = metaslab_class_get_space(spa_normal_class(spa));
5621                 mutex_exit(&spa_namespace_lock);
5622 
5623                 /*
5624                  * If the pool grew as a result of the config update,
5625                  * then log an internal history event.
5626                  */
5627                 if (new_space != old_space) {
5628                         spa_history_log_internal(spa, "vdev online", NULL,
5629                             "pool '%s' size: %llu(+%llu)",
5630                             spa_name(spa), new_space, new_space - old_space);
5631                 }
5632         }
5633 
5634         /*
5635          * See if any devices need to be marked REMOVED.
5636          */
5637         if (tasks & SPA_ASYNC_REMOVE) {
5638                 spa_vdev_state_enter(spa, SCL_NONE);
5639                 spa_async_remove(spa, spa->spa_root_vdev);
5640                 for (int i = 0; i < spa->spa_l2cache.sav_count; i++)
5641                         spa_async_remove(spa, spa->spa_l2cache.sav_vdevs[i]);
5642                 for (int i = 0; i < spa->spa_spares.sav_count; i++)
5643                         spa_async_remove(spa, spa->spa_spares.sav_vdevs[i]);
5644                 (void) spa_vdev_state_exit(spa, NULL, 0);
5645         }
5646 
5647         if ((tasks & SPA_ASYNC_AUTOEXPAND) && !spa_suspended(spa)) {
5648                 spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
5649                 spa_async_autoexpand(spa, spa->spa_root_vdev);
5650                 spa_config_exit(spa, SCL_CONFIG, FTAG);
5651         }
5652 
5653         /*
5654          * See if any devices need to be probed.
5655          */
5656         if (tasks & SPA_ASYNC_PROBE) {
5657                 spa_vdev_state_enter(spa, SCL_NONE);
5658                 spa_async_probe(spa, spa->spa_root_vdev);
5659                 (void) spa_vdev_state_exit(spa, NULL, 0);
5660         }
5661 
5662         /*
5663          * If any devices are done replacing, detach them.
5664          */
5665         if (tasks & SPA_ASYNC_RESILVER_DONE)
5666                 spa_vdev_resilver_done(spa);
5667 
5668         /*
5669          * Kick off a resilver.
5670          */
5671         if (tasks & SPA_ASYNC_RESILVER)
5672                 dsl_resilver_restart(spa->spa_dsl_pool, 0);
5673 
5674         /*
5675          * Let the world know that we're done.
5676          */
5677         mutex_enter(&spa->spa_async_lock);
5678         spa->spa_async_thread = NULL;
5679         cv_broadcast(&spa->spa_async_cv);
5680         mutex_exit(&spa->spa_async_lock);
5681         thread_exit();
5682 }
5683 
5684 void
5685 spa_async_suspend(spa_t *spa)
5686 {
5687         mutex_enter(&spa->spa_async_lock);
5688         spa->spa_async_suspended++;
5689         while (spa->spa_async_thread != NULL)
5690                 cv_wait(&spa->spa_async_cv, &spa->spa_async_lock);
5691         mutex_exit(&spa->spa_async_lock);
5692 }
5693 
5694 void
5695 spa_async_resume(spa_t *spa)
5696 {
5697         mutex_enter(&spa->spa_async_lock);
5698         ASSERT(spa->spa_async_suspended != 0);
5699         spa->spa_async_suspended--;
5700         mutex_exit(&spa->spa_async_lock);
5701 }
5702 
5703 static boolean_t
5704 spa_async_tasks_pending(spa_t *spa)
5705 {
5706         uint_t non_config_tasks;
5707         uint_t config_task;
5708         boolean_t config_task_suspended;
5709 
5710         non_config_tasks = spa->spa_async_tasks & ~SPA_ASYNC_CONFIG_UPDATE;
5711         config_task = spa->spa_async_tasks & SPA_ASYNC_CONFIG_UPDATE;
5712         if (spa->spa_ccw_fail_time == 0) {
5713                 config_task_suspended = B_FALSE;
5714         } else {
5715                 config_task_suspended =
5716                     (gethrtime() - spa->spa_ccw_fail_time) <
5717                     (zfs_ccw_retry_interval * NANOSEC);
5718         }
5719 
5720         return (non_config_tasks || (config_task && !config_task_suspended));
5721 }
5722 
5723 static void
5724 spa_async_dispatch(spa_t *spa)
5725 {
5726         mutex_enter(&spa->spa_async_lock);
5727         if (spa_async_tasks_pending(spa) &&
5728             !spa->spa_async_suspended &&
5729             spa->spa_async_thread == NULL &&
5730             rootdir != NULL)
5731                 spa->spa_async_thread = thread_create(NULL, 0,
5732                     spa_async_thread, spa, 0, &p0, TS_RUN, maxclsyspri);
5733         mutex_exit(&spa->spa_async_lock);
5734 }
5735 
5736 void
5737 spa_async_request(spa_t *spa, int task)
5738 {
5739         zfs_dbgmsg("spa=%s async request task=%u", spa->spa_name, task);
5740         mutex_enter(&spa->spa_async_lock);
5741         spa->spa_async_tasks |= task;
5742         mutex_exit(&spa->spa_async_lock);
5743 }
5744 
5745 /*
5746  * ==========================================================================
5747  * SPA syncing routines
5748  * ==========================================================================
5749  */
5750 
5751 static int
5752 bpobj_enqueue_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
5753 {
5754         bpobj_t *bpo = arg;
5755         bpobj_enqueue(bpo, bp, tx);
5756         return (0);
5757 }
5758 
5759 static int
5760 spa_free_sync_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
5761 {
5762         zio_t *zio = arg;
5763 
5764         zio_nowait(zio_free_sync(zio, zio->io_spa, dmu_tx_get_txg(tx), bp,
5765             zio->io_flags));
5766         return (0);
5767 }
5768 
5769 /*
5770  * Note: this simple function is not inlined to make it easier to dtrace the
5771  * amount of time spent syncing frees.
5772  */
5773 static void
5774 spa_sync_frees(spa_t *spa, bplist_t *bpl, dmu_tx_t *tx)
5775 {
5776         zio_t *zio = zio_root(spa, NULL, NULL, 0);
5777         bplist_iterate(bpl, spa_free_sync_cb, zio, tx);
5778         VERIFY(zio_wait(zio) == 0);
5779 }
5780 
5781 /*
5782  * Note: this simple function is not inlined to make it easier to dtrace the
5783  * amount of time spent syncing deferred frees.
5784  */
5785 static void
5786 spa_sync_deferred_frees(spa_t *spa, dmu_tx_t *tx)
5787 {
5788         zio_t *zio = zio_root(spa, NULL, NULL, 0);
5789         VERIFY3U(bpobj_iterate(&spa->spa_deferred_bpobj,
5790             spa_free_sync_cb, zio, tx), ==, 0);
5791         VERIFY0(zio_wait(zio));
5792 }
5793 
5794 
5795 static void
5796 spa_sync_nvlist(spa_t *spa, uint64_t obj, nvlist_t *nv, dmu_tx_t *tx)
5797 {
5798         char *packed = NULL;
5799         size_t bufsize;
5800         size_t nvsize = 0;
5801         dmu_buf_t *db;
5802 
5803         VERIFY(nvlist_size(nv, &nvsize, NV_ENCODE_XDR) == 0);
5804 
5805         /*
5806          * Write full (SPA_CONFIG_BLOCKSIZE) blocks of configuration
5807          * information.  This avoids the dmu_buf_will_dirty() path and
5808          * saves us a pre-read to get data we don't actually care about.
5809          */
5810         bufsize = P2ROUNDUP((uint64_t)nvsize, SPA_CONFIG_BLOCKSIZE);
5811         packed = kmem_alloc(bufsize, KM_SLEEP);
5812 
5813         VERIFY(nvlist_pack(nv, &packed, &nvsize, NV_ENCODE_XDR,
5814             KM_SLEEP) == 0);
5815         bzero(packed + nvsize, bufsize - nvsize);
5816 
5817         dmu_write(spa->spa_meta_objset, obj, 0, bufsize, packed, tx);
5818 
5819         kmem_free(packed, bufsize);
5820 
5821         VERIFY(0 == dmu_bonus_hold(spa->spa_meta_objset, obj, FTAG, &db));
5822         dmu_buf_will_dirty(db, tx);
5823         *(uint64_t *)db->db_data = nvsize;
5824         dmu_buf_rele(db, FTAG);
5825 }
5826 
5827 static void
5828 spa_sync_aux_dev(spa_t *spa, spa_aux_vdev_t *sav, dmu_tx_t *tx,
5829     const char *config, const char *entry)
5830 {
5831         nvlist_t *nvroot;
5832         nvlist_t **list;
5833         int i;
5834 
5835         if (!sav->sav_sync)
5836                 return;
5837 
5838         /*
5839          * Update the MOS nvlist describing the list of available devices.
5840          * spa_validate_aux() will have already made sure this nvlist is
5841          * valid and the vdevs are labeled appropriately.
5842          */
5843         if (sav->sav_object == 0) {
5844                 sav->sav_object = dmu_object_alloc(spa->spa_meta_objset,
5845                     DMU_OT_PACKED_NVLIST, 1 << 14, DMU_OT_PACKED_NVLIST_SIZE,
5846                     sizeof (uint64_t), tx);
5847                 VERIFY(zap_update(spa->spa_meta_objset,
5848                     DMU_POOL_DIRECTORY_OBJECT, entry, sizeof (uint64_t), 1,
5849                     &sav->sav_object, tx) == 0);
5850         }
5851 
5852         VERIFY(nvlist_alloc(&nvroot, NV_UNIQUE_NAME, KM_SLEEP) == 0);
5853         if (sav->sav_count == 0) {
5854                 VERIFY(nvlist_add_nvlist_array(nvroot, config, NULL, 0) == 0);
5855         } else {
5856                 list = kmem_alloc(sav->sav_count * sizeof (void *), KM_SLEEP);
5857                 for (i = 0; i < sav->sav_count; i++)
5858                         list[i] = vdev_config_generate(spa, sav->sav_vdevs[i],
5859                             B_FALSE, VDEV_CONFIG_L2CACHE);
5860                 VERIFY(nvlist_add_nvlist_array(nvroot, config, list,
5861                     sav->sav_count) == 0);
5862                 for (i = 0; i < sav->sav_count; i++)
5863                         nvlist_free(list[i]);
5864                 kmem_free(list, sav->sav_count * sizeof (void *));
5865         }
5866 
5867         spa_sync_nvlist(spa, sav->sav_object, nvroot, tx);
5868         nvlist_free(nvroot);
5869 
5870         sav->sav_sync = B_FALSE;
5871 }
5872 
5873 static void
5874 spa_sync_config_object(spa_t *spa, dmu_tx_t *tx)
5875 {
5876         nvlist_t *config;
5877 
5878         if (list_is_empty(&spa->spa_config_dirty_list))
5879                 return;
5880 
5881         spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
5882 
5883         config = spa_config_generate(spa, spa->spa_root_vdev,
5884             dmu_tx_get_txg(tx), B_FALSE);
5885 
5886         /*
5887          * If we're upgrading the spa version then make sure that
5888          * the config object gets updated with the correct version.
5889          */
5890         if (spa->spa_ubsync.ub_version < spa->spa_uberblock.ub_version)
5891                 fnvlist_add_uint64(config, ZPOOL_CONFIG_VERSION,
5892                     spa->spa_uberblock.ub_version);
5893 
5894         spa_config_exit(spa, SCL_STATE, FTAG);
5895 
5896         if (spa->spa_config_syncing)
5897                 nvlist_free(spa->spa_config_syncing);
5898         spa->spa_config_syncing = config;
5899 
5900         spa_sync_nvlist(spa, spa->spa_config_object, config, tx);
5901 }
5902 
5903 static void
5904 spa_sync_version(void *arg, dmu_tx_t *tx)
5905 {
5906         uint64_t *versionp = arg;
5907         uint64_t version = *versionp;
5908         spa_t *spa = dmu_tx_pool(tx)->dp_spa;
5909 
5910         /*
5911          * Setting the version is special cased when first creating the pool.
5912          */
5913         ASSERT(tx->tx_txg != TXG_INITIAL);
5914 
5915         ASSERT(SPA_VERSION_IS_SUPPORTED(version));
5916         ASSERT(version >= spa_version(spa));
5917 
5918         spa->spa_uberblock.ub_version = version;
5919         vdev_config_dirty(spa->spa_root_vdev);
5920         spa_history_log_internal(spa, "set", tx, "version=%lld", version);
5921 }
5922 
5923 /*
5924  * Set zpool properties.
5925  */
5926 static void
5927 spa_sync_props(void *arg, dmu_tx_t *tx)
5928 {
5929         nvlist_t *nvp = arg;
5930         spa_t *spa = dmu_tx_pool(tx)->dp_spa;
5931         objset_t *mos = spa->spa_meta_objset;
5932         nvpair_t *elem = NULL;
5933 
5934         mutex_enter(&spa->spa_props_lock);
5935 
5936         while ((elem = nvlist_next_nvpair(nvp, elem))) {
5937                 uint64_t intval;
5938                 char *strval, *fname;
5939                 zpool_prop_t prop;
5940                 const char *propname;
5941                 zprop_type_t proptype;
5942                 spa_feature_t fid;
5943 
5944                 switch (prop = zpool_name_to_prop(nvpair_name(elem))) {
5945                 case ZPROP_INVAL:
5946                         /*
5947                          * We checked this earlier in spa_prop_validate().
5948                          */
5949                         ASSERT(zpool_prop_feature(nvpair_name(elem)));
5950 
5951                         fname = strchr(nvpair_name(elem), '@') + 1;
5952                         VERIFY0(zfeature_lookup_name(fname, &fid));
5953 
5954                         spa_feature_enable(spa, fid, tx);
5955                         spa_history_log_internal(spa, "set", tx,
5956                             "%s=enabled", nvpair_name(elem));
5957                         break;
5958 
5959                 case ZPOOL_PROP_VERSION:
5960                         intval = fnvpair_value_uint64(elem);
5961                         /*
5962                          * The version is synced seperatly before other
5963                          * properties and should be correct by now.
5964                          */
5965                         ASSERT3U(spa_version(spa), >=, intval);
5966                         break;
5967 
5968                 case ZPOOL_PROP_ALTROOT:
5969                         /*
5970                          * 'altroot' is a non-persistent property. It should
5971                          * have been set temporarily at creation or import time.
5972                          */
5973                         ASSERT(spa->spa_root != NULL);
5974                         break;
5975 
5976                 case ZPOOL_PROP_READONLY:
5977                 case ZPOOL_PROP_CACHEFILE:
5978                         /*
5979                          * 'readonly' and 'cachefile' are also non-persisitent
5980                          * properties.
5981                          */
5982                         break;
5983                 case ZPOOL_PROP_COMMENT:
5984                         strval = fnvpair_value_string(elem);
5985                         if (spa->spa_comment != NULL)
5986                                 spa_strfree(spa->spa_comment);
5987                         spa->spa_comment = spa_strdup(strval);
5988                         /*
5989                          * We need to dirty the configuration on all the vdevs
5990                          * so that their labels get updated.  It's unnecessary
5991                          * to do this for pool creation since the vdev's
5992                          * configuratoin has already been dirtied.
5993                          */
5994                         if (tx->tx_txg != TXG_INITIAL)
5995                                 vdev_config_dirty(spa->spa_root_vdev);
5996                         spa_history_log_internal(spa, "set", tx,
5997                             "%s=%s", nvpair_name(elem), strval);
5998                         break;
5999                 default:
6000                         /*
6001                          * Set pool property values in the poolprops mos object.
6002                          */
6003                         if (spa->spa_pool_props_object == 0) {
6004                                 spa->spa_pool_props_object =
6005                                     zap_create_link(mos, DMU_OT_POOL_PROPS,
6006                                     DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_PROPS,
6007                                     tx);
6008                         }
6009 
6010                         /* normalize the property name */
6011                         propname = zpool_prop_to_name(prop);
6012                         proptype = zpool_prop_get_type(prop);
6013 
6014                         if (nvpair_type(elem) == DATA_TYPE_STRING) {
6015                                 ASSERT(proptype == PROP_TYPE_STRING);
6016                                 strval = fnvpair_value_string(elem);
6017                                 VERIFY0(zap_update(mos,
6018                                     spa->spa_pool_props_object, propname,
6019                                     1, strlen(strval) + 1, strval, tx));
6020                                 spa_history_log_internal(spa, "set", tx,
6021                                     "%s=%s", nvpair_name(elem), strval);
6022                         } else if (nvpair_type(elem) == DATA_TYPE_UINT64) {
6023                                 intval = fnvpair_value_uint64(elem);
6024 
6025                                 if (proptype == PROP_TYPE_INDEX) {
6026                                         const char *unused;
6027                                         VERIFY0(zpool_prop_index_to_string(
6028                                             prop, intval, &unused));
6029                                 }
6030                                 VERIFY0(zap_update(mos,
6031                                     spa->spa_pool_props_object, propname,
6032                                     8, 1, &intval, tx));
6033                                 spa_history_log_internal(spa, "set", tx,
6034                                     "%s=%lld", nvpair_name(elem), intval);
6035                         } else {
6036                                 ASSERT(0); /* not allowed */
6037                         }
6038 
6039                         switch (prop) {
6040                         case ZPOOL_PROP_DELEGATION:
6041                                 spa->spa_delegation = intval;
6042                                 break;
6043                         case ZPOOL_PROP_BOOTFS:
6044                                 spa->spa_bootfs = intval;
6045                                 break;
6046                         case ZPOOL_PROP_FAILUREMODE:
6047                                 spa->spa_failmode = intval;
6048                                 break;
6049                         case ZPOOL_PROP_AUTOEXPAND:
6050                                 spa->spa_autoexpand = intval;
6051                                 if (tx->tx_txg != TXG_INITIAL)
6052                                         spa_async_request(spa,
6053                                             SPA_ASYNC_AUTOEXPAND);
6054                                 break;
6055                         case ZPOOL_PROP_DEDUPDITTO:
6056                                 spa->spa_dedup_ditto = intval;
6057                                 break;
6058                         default:
6059                                 break;
6060                         }
6061                 }
6062 
6063         }
6064 
6065         mutex_exit(&spa->spa_props_lock);
6066 }
6067 
6068 /*
6069  * Perform one-time upgrade on-disk changes.  spa_version() does not
6070  * reflect the new version this txg, so there must be no changes this
6071  * txg to anything that the upgrade code depends on after it executes.
6072  * Therefore this must be called after dsl_pool_sync() does the sync
6073  * tasks.
6074  */
6075 static void
6076 spa_sync_upgrades(spa_t *spa, dmu_tx_t *tx)
6077 {
6078         dsl_pool_t *dp = spa->spa_dsl_pool;
6079 
6080         ASSERT(spa->spa_sync_pass == 1);
6081 
6082         rrw_enter(&dp->dp_config_rwlock, RW_WRITER, FTAG);
6083 
6084         if (spa->spa_ubsync.ub_version < SPA_VERSION_ORIGIN &&
6085             spa->spa_uberblock.ub_version >= SPA_VERSION_ORIGIN) {
6086                 dsl_pool_create_origin(dp, tx);
6087 
6088                 /* Keeping the origin open increases spa_minref */
6089                 spa->spa_minref += 3;
6090         }
6091 
6092         if (spa->spa_ubsync.ub_version < SPA_VERSION_NEXT_CLONES &&
6093             spa->spa_uberblock.ub_version >= SPA_VERSION_NEXT_CLONES) {
6094                 dsl_pool_upgrade_clones(dp, tx);
6095         }
6096 
6097         if (spa->spa_ubsync.ub_version < SPA_VERSION_DIR_CLONES &&
6098             spa->spa_uberblock.ub_version >= SPA_VERSION_DIR_CLONES) {
6099                 dsl_pool_upgrade_dir_clones(dp, tx);
6100 
6101                 /* Keeping the freedir open increases spa_minref */
6102                 spa->spa_minref += 3;
6103         }
6104 
6105         if (spa->spa_ubsync.ub_version < SPA_VERSION_FEATURES &&
6106             spa->spa_uberblock.ub_version >= SPA_VERSION_FEATURES) {
6107                 spa_feature_create_zap_objects(spa, tx);
6108         }
6109 
6110         if (spa->spa_uberblock.ub_version >= SPA_VERSION_FEATURES) {
6111                 boolean_t lz4_en = spa_feature_is_enabled(spa,
6112                     SPA_FEATURE_LZ4_COMPRESS);
6113                 boolean_t lz4_ac = spa_feature_is_active(spa,
6114                     SPA_FEATURE_LZ4_COMPRESS);
6115 
6116                 if (lz4_en && !lz4_ac)
6117                         spa_feature_incr(spa, SPA_FEATURE_LZ4_COMPRESS, tx);
6118         }
6119         rrw_exit(&dp->dp_config_rwlock, FTAG);
6120 }
6121 
6122 /*
6123  * Sync the specified transaction group.  New blocks may be dirtied as
6124  * part of the process, so we iterate until it converges.
6125  */
6126 void
6127 spa_sync(spa_t *spa, uint64_t txg)
6128 {
6129         dsl_pool_t *dp = spa->spa_dsl_pool;
6130         objset_t *mos = spa->spa_meta_objset;
6131         bplist_t *free_bpl = &spa->spa_free_bplist[txg & TXG_MASK];
6132         vdev_t *rvd = spa->spa_root_vdev;
6133         vdev_t *vd;
6134         dmu_tx_t *tx;
6135         int error;
6136 
6137         VERIFY(spa_writeable(spa));
6138 
6139         /*
6140          * Lock out configuration changes.
6141          */
6142         spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
6143 
6144         spa->spa_syncing_txg = txg;
6145         spa->spa_sync_pass = 0;
6146 
6147         /*
6148          * If there are any pending vdev state changes, convert them
6149          * into config changes that go out with this transaction group.
6150          */
6151         spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
6152         while (list_head(&spa->spa_state_dirty_list) != NULL) {
6153                 /*
6154                  * We need the write lock here because, for aux vdevs,
6155                  * calling vdev_config_dirty() modifies sav_config.
6156                  * This is ugly and will become unnecessary when we
6157                  * eliminate the aux vdev wart by integrating all vdevs
6158                  * into the root vdev tree.
6159                  */
6160                 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
6161                 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_WRITER);
6162                 while ((vd = list_head(&spa->spa_state_dirty_list)) != NULL) {
6163                         vdev_state_clean(vd);
6164                         vdev_config_dirty(vd);
6165                 }
6166                 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
6167                 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER);
6168         }
6169         spa_config_exit(spa, SCL_STATE, FTAG);
6170 
6171         tx = dmu_tx_create_assigned(dp, txg);
6172 
6173         spa->spa_sync_starttime = gethrtime();
6174         VERIFY(cyclic_reprogram(spa->spa_deadman_cycid,
6175             spa->spa_sync_starttime + spa->spa_deadman_synctime));
6176 
6177         /*
6178          * If we are upgrading to SPA_VERSION_RAIDZ_DEFLATE this txg,
6179          * set spa_deflate if we have no raid-z vdevs.
6180          */
6181         if (spa->spa_ubsync.ub_version < SPA_VERSION_RAIDZ_DEFLATE &&
6182             spa->spa_uberblock.ub_version >= SPA_VERSION_RAIDZ_DEFLATE) {
6183                 int i;
6184 
6185                 for (i = 0; i < rvd->vdev_children; i++) {
6186                         vd = rvd->vdev_child[i];
6187                         if (vd->vdev_deflate_ratio != SPA_MINBLOCKSIZE)
6188                                 break;
6189                 }
6190                 if (i == rvd->vdev_children) {
6191                         spa->spa_deflate = TRUE;
6192                         VERIFY(0 == zap_add(spa->spa_meta_objset,
6193                             DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_DEFLATE,
6194                             sizeof (uint64_t), 1, &spa->spa_deflate, tx));
6195                 }
6196         }
6197 
6198         /*
6199          * If anything has changed in this txg, or if someone is waiting
6200          * for this txg to sync (eg, spa_vdev_remove()), push the
6201          * deferred frees from the previous txg.  If not, leave them
6202          * alone so that we don't generate work on an otherwise idle
6203          * system.
6204          */
6205         if (!txg_list_empty(&dp->dp_dirty_datasets, txg) ||
6206             !txg_list_empty(&dp->dp_dirty_dirs, txg) ||
6207             !txg_list_empty(&dp->dp_sync_tasks, txg) ||
6208             ((dsl_scan_active(dp->dp_scan) ||
6209             txg_sync_waiting(dp)) && !spa_shutting_down(spa))) {
6210                 spa_sync_deferred_frees(spa, tx);
6211         }
6212 
6213         /*
6214          * Iterate to convergence.
6215          */
6216         do {
6217                 int pass = ++spa->spa_sync_pass;
6218 
6219                 spa_sync_config_object(spa, tx);
6220                 spa_sync_aux_dev(spa, &spa->spa_spares, tx,
6221                     ZPOOL_CONFIG_SPARES, DMU_POOL_SPARES);
6222                 spa_sync_aux_dev(spa, &spa->spa_l2cache, tx,
6223                     ZPOOL_CONFIG_L2CACHE, DMU_POOL_L2CACHE);
6224                 spa_errlog_sync(spa, txg);
6225                 dsl_pool_sync(dp, txg);
6226 
6227                 if (pass < zfs_sync_pass_deferred_free) {
6228                         spa_sync_frees(spa, free_bpl, tx);
6229                 } else {
6230                         bplist_iterate(free_bpl, bpobj_enqueue_cb,
6231                             &spa->spa_deferred_bpobj, tx);
6232                 }
6233 
6234                 ddt_sync(spa, txg);
6235                 dsl_scan_sync(dp, tx);
6236 
6237                 while (vd = txg_list_remove(&spa->spa_vdev_txg_list, txg))
6238                         vdev_sync(vd, txg);
6239 
6240                 if (pass == 1)
6241                         spa_sync_upgrades(spa, tx);
6242 
6243         } while (dmu_objset_is_dirty(mos, txg));
6244 
6245         /*
6246          * Rewrite the vdev configuration (which includes the uberblock)
6247          * to commit the transaction group.
6248          *
6249          * If there are no dirty vdevs, we sync the uberblock to a few
6250          * random top-level vdevs that are known to be visible in the
6251          * config cache (see spa_vdev_add() for a complete description).
6252          * If there *are* dirty vdevs, sync the uberblock to all vdevs.
6253          */
6254         for (;;) {
6255                 /*
6256                  * We hold SCL_STATE to prevent vdev open/close/etc.
6257                  * while we're attempting to write the vdev labels.
6258                  */
6259                 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
6260 
6261                 if (list_is_empty(&spa->spa_config_dirty_list)) {
6262                         vdev_t *svd[SPA_DVAS_PER_BP];
6263                         int svdcount = 0;
6264                         int children = rvd->vdev_children;
6265                         int c0 = spa_get_random(children);
6266 
6267                         for (int c = 0; c < children; c++) {
6268                                 vd = rvd->vdev_child[(c0 + c) % children];
6269                                 if (vd->vdev_ms_array == 0 || vd->vdev_islog)
6270                                         continue;
6271                                 svd[svdcount++] = vd;
6272                                 if (svdcount == SPA_DVAS_PER_BP)
6273                                         break;
6274                         }
6275                         error = vdev_config_sync(svd, svdcount, txg, B_FALSE);
6276                         if (error != 0)
6277                                 error = vdev_config_sync(svd, svdcount, txg,
6278                                     B_TRUE);
6279                 } else {
6280                         error = vdev_config_sync(rvd->vdev_child,
6281                             rvd->vdev_children, txg, B_FALSE);
6282                         if (error != 0)
6283                                 error = vdev_config_sync(rvd->vdev_child,
6284                                     rvd->vdev_children, txg, B_TRUE);
6285                 }
6286 
6287                 if (error == 0)
6288                         spa->spa_last_synced_guid = rvd->vdev_guid;
6289 
6290                 spa_config_exit(spa, SCL_STATE, FTAG);
6291 
6292                 if (error == 0)
6293                         break;
6294                 zio_suspend(spa, NULL);
6295                 zio_resume_wait(spa);
6296         }
6297         dmu_tx_commit(tx);
6298 
6299         VERIFY(cyclic_reprogram(spa->spa_deadman_cycid, CY_INFINITY));
6300 
6301         /*
6302          * Clear the dirty config list.
6303          */
6304         while ((vd = list_head(&spa->spa_config_dirty_list)) != NULL)
6305                 vdev_config_clean(vd);
6306 
6307         /*
6308          * Now that the new config has synced transactionally,
6309          * let it become visible to the config cache.
6310          */
6311         if (spa->spa_config_syncing != NULL) {
6312                 spa_config_set(spa, spa->spa_config_syncing);
6313                 spa->spa_config_txg = txg;
6314                 spa->spa_config_syncing = NULL;
6315         }
6316 
6317         spa->spa_ubsync = spa->spa_uberblock;
6318 
6319         dsl_pool_sync_done(dp, txg);
6320 
6321         /*
6322          * Update usable space statistics.
6323          */
6324         while (vd = txg_list_remove(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)))
6325                 vdev_sync_done(vd, txg);
6326 
6327         spa_update_dspace(spa);
6328 
6329         /*
6330          * It had better be the case that we didn't dirty anything
6331          * since vdev_config_sync().
6332          */
6333         ASSERT(txg_list_empty(&dp->dp_dirty_datasets, txg));
6334         ASSERT(txg_list_empty(&dp->dp_dirty_dirs, txg));
6335         ASSERT(txg_list_empty(&spa->spa_vdev_txg_list, txg));
6336 
6337         spa->spa_sync_pass = 0;
6338 
6339         spa_config_exit(spa, SCL_CONFIG, FTAG);
6340 
6341         spa_handle_ignored_writes(spa);
6342 
6343         /*
6344          * If any async tasks have been requested, kick them off.
6345          */
6346         spa_async_dispatch(spa);
6347 }
6348 
6349 /*
6350  * Sync all pools.  We don't want to hold the namespace lock across these
6351  * operations, so we take a reference on the spa_t and drop the lock during the
6352  * sync.
6353  */
6354 void
6355 spa_sync_allpools(void)
6356 {
6357         spa_t *spa = NULL;
6358         mutex_enter(&spa_namespace_lock);
6359         while ((spa = spa_next(spa)) != NULL) {
6360                 if (spa_state(spa) != POOL_STATE_ACTIVE ||
6361                     !spa_writeable(spa) || spa_suspended(spa))
6362                         continue;
6363                 spa_open_ref(spa, FTAG);
6364                 mutex_exit(&spa_namespace_lock);
6365                 txg_wait_synced(spa_get_dsl(spa), 0);
6366                 mutex_enter(&spa_namespace_lock);
6367                 spa_close(spa, FTAG);
6368         }
6369         mutex_exit(&spa_namespace_lock);
6370 }
6371 
6372 /*
6373  * ==========================================================================
6374  * Miscellaneous routines
6375  * ==========================================================================
6376  */
6377 
6378 /*
6379  * Remove all pools in the system.
6380  */
6381 void
6382 spa_evict_all(void)
6383 {
6384         spa_t *spa;
6385 
6386         /*
6387          * Remove all cached state.  All pools should be closed now,
6388          * so every spa in the AVL tree should be unreferenced.
6389          */
6390         mutex_enter(&spa_namespace_lock);
6391         while ((spa = spa_next(NULL)) != NULL) {
6392                 /*
6393                  * Stop async tasks.  The async thread may need to detach
6394                  * a device that's been replaced, which requires grabbing
6395                  * spa_namespace_lock, so we must drop it here.
6396                  */
6397                 spa_open_ref(spa, FTAG);
6398                 mutex_exit(&spa_namespace_lock);
6399                 spa_async_suspend(spa);
6400                 mutex_enter(&spa_namespace_lock);
6401                 spa_close(spa, FTAG);
6402 
6403                 if (spa->spa_state != POOL_STATE_UNINITIALIZED) {
6404                         spa_unload(spa);
6405                         spa_deactivate(spa);
6406                 }
6407                 spa_remove(spa);
6408         }
6409         mutex_exit(&spa_namespace_lock);
6410 }
6411 
6412 vdev_t *
6413 spa_lookup_by_guid(spa_t *spa, uint64_t guid, boolean_t aux)
6414 {
6415         vdev_t *vd;
6416         int i;
6417 
6418         if ((vd = vdev_lookup_by_guid(spa->spa_root_vdev, guid)) != NULL)
6419                 return (vd);
6420 
6421         if (aux) {
6422                 for (i = 0; i < spa->spa_l2cache.sav_count; i++) {
6423                         vd = spa->spa_l2cache.sav_vdevs[i];
6424                         if (vd->vdev_guid == guid)
6425                                 return (vd);
6426                 }
6427 
6428                 for (i = 0; i < spa->spa_spares.sav_count; i++) {
6429                         vd = spa->spa_spares.sav_vdevs[i];
6430                         if (vd->vdev_guid == guid)
6431                                 return (vd);
6432                 }
6433         }
6434 
6435         return (NULL);
6436 }
6437 
6438 void
6439 spa_upgrade(spa_t *spa, uint64_t version)
6440 {
6441         ASSERT(spa_writeable(spa));
6442 
6443         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
6444 
6445         /*
6446          * This should only be called for a non-faulted pool, and since a
6447          * future version would result in an unopenable pool, this shouldn't be
6448          * possible.
6449          */
6450         ASSERT(SPA_VERSION_IS_SUPPORTED(spa->spa_uberblock.ub_version));
6451         ASSERT(version >= spa->spa_uberblock.ub_version);
6452 
6453         spa->spa_uberblock.ub_version = version;
6454         vdev_config_dirty(spa->spa_root_vdev);
6455 
6456         spa_config_exit(spa, SCL_ALL, FTAG);
6457 
6458         txg_wait_synced(spa_get_dsl(spa), 0);
6459 }
6460 
6461 boolean_t
6462 spa_has_spare(spa_t *spa, uint64_t guid)
6463 {
6464         int i;
6465         uint64_t spareguid;
6466         spa_aux_vdev_t *sav = &spa->spa_spares;
6467 
6468         for (i = 0; i < sav->sav_count; i++)
6469                 if (sav->sav_vdevs[i]->vdev_guid == guid)
6470                         return (B_TRUE);
6471 
6472         for (i = 0; i < sav->sav_npending; i++) {
6473                 if (nvlist_lookup_uint64(sav->sav_pending[i], ZPOOL_CONFIG_GUID,
6474                     &spareguid) == 0 && spareguid == guid)
6475                         return (B_TRUE);
6476         }
6477 
6478         return (B_FALSE);
6479 }
6480 
6481 /*
6482  * Check if a pool has an active shared spare device.
6483  * Note: reference count of an active spare is 2, as a spare and as a replace
6484  */
6485 static boolean_t
6486 spa_has_active_shared_spare(spa_t *spa)
6487 {
6488         int i, refcnt;
6489         uint64_t pool;
6490         spa_aux_vdev_t *sav = &spa->spa_spares;
6491 
6492         for (i = 0; i < sav->sav_count; i++) {
6493                 if (spa_spare_exists(sav->sav_vdevs[i]->vdev_guid, &pool,
6494                     &refcnt) && pool != 0ULL && pool == spa_guid(spa) &&
6495                     refcnt > 2)
6496                         return (B_TRUE);
6497         }
6498 
6499         return (B_FALSE);
6500 }
6501 
6502 /*
6503  * Post a sysevent corresponding to the given event.  The 'name' must be one of
6504  * the event definitions in sys/sysevent/eventdefs.h.  The payload will be
6505  * filled in from the spa and (optionally) the vdev.  This doesn't do anything
6506  * in the userland libzpool, as we don't want consumers to misinterpret ztest
6507  * or zdb as real changes.
6508  */
6509 void
6510 spa_event_notify(spa_t *spa, vdev_t *vd, const char *name)
6511 {
6512 #ifdef _KERNEL
6513         sysevent_t              *ev;
6514         sysevent_attr_list_t    *attr = NULL;
6515         sysevent_value_t        value;
6516         sysevent_id_t           eid;
6517 
6518         ev = sysevent_alloc(EC_ZFS, (char *)name, SUNW_KERN_PUB "zfs",
6519             SE_SLEEP);
6520 
6521         value.value_type = SE_DATA_TYPE_STRING;
6522         value.value.sv_string = spa_name(spa);
6523         if (sysevent_add_attr(&attr, ZFS_EV_POOL_NAME, &value, SE_SLEEP) != 0)
6524                 goto done;
6525 
6526         value.value_type = SE_DATA_TYPE_UINT64;
6527         value.value.sv_uint64 = spa_guid(spa);
6528         if (sysevent_add_attr(&attr, ZFS_EV_POOL_GUID, &value, SE_SLEEP) != 0)
6529                 goto done;
6530 
6531         if (vd) {
6532                 value.value_type = SE_DATA_TYPE_UINT64;
6533                 value.value.sv_uint64 = vd->vdev_guid;
6534                 if (sysevent_add_attr(&attr, ZFS_EV_VDEV_GUID, &value,
6535                     SE_SLEEP) != 0)
6536                         goto done;
6537 
6538                 if (vd->vdev_path) {
6539                         value.value_type = SE_DATA_TYPE_STRING;
6540                         value.value.sv_string = vd->vdev_path;
6541                         if (sysevent_add_attr(&attr, ZFS_EV_VDEV_PATH,
6542                             &value, SE_SLEEP) != 0)
6543                                 goto done;
6544                 }
6545         }
6546 
6547         if (sysevent_attach_attributes(ev, attr) != 0)
6548                 goto done;
6549         attr = NULL;
6550 
6551         (void) log_sysevent(ev, SE_SLEEP, &eid);
6552 
6553 done:
6554         if (attr)
6555                 sysevent_free_attr(attr);
6556         sysevent_free(ev);
6557 #endif
6558 }