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) 2013 by Delphix. All rights reserved.
  25  * Copyright 2013 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_BATCH,      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                                 boolean_t do_rebuild = B_FALSE;
1490 
1491                                 (void) nvlist_lookup_boolean_value(l2cache[i],
1492                                     ZPOOL_CONFIG_L2CACHE_PERSISTENT,
1493                                     &do_rebuild);
1494                                 l2arc_add_vdev(spa, vd, do_rebuild);
1495                         }
1496                 }
1497         }
1498 
1499         /*
1500          * Purge vdevs that were dropped
1501          */
1502         for (i = 0; i < oldnvdevs; i++) {
1503                 uint64_t pool;
1504 
1505                 vd = oldvdevs[i];
1506                 if (vd != NULL) {
1507                         ASSERT(vd->vdev_isl2cache);
1508 
1509                         if (spa_l2cache_exists(vd->vdev_guid, &pool) &&
1510                             pool != 0ULL && l2arc_vdev_present(vd))
1511                                 l2arc_remove_vdev(vd);
1512                         vdev_clear_stats(vd);
1513                         vdev_free(vd);
1514                 }
1515         }
1516 
1517         if (oldvdevs)
1518                 kmem_free(oldvdevs, oldnvdevs * sizeof (void *));
1519 
1520         if (sav->sav_config == NULL)
1521                 goto out;
1522 
1523         sav->sav_vdevs = newvdevs;
1524         sav->sav_count = (int)nl2cache;
1525 
1526         /*
1527          * Recompute the stashed list of l2cache devices, with status
1528          * information this time.
1529          */
1530         VERIFY(nvlist_remove(sav->sav_config, ZPOOL_CONFIG_L2CACHE,
1531             DATA_TYPE_NVLIST_ARRAY) == 0);
1532 
1533         l2cache = kmem_alloc(sav->sav_count * sizeof (void *), KM_SLEEP);
1534         for (i = 0; i < sav->sav_count; i++)
1535                 l2cache[i] = vdev_config_generate(spa,
1536                     sav->sav_vdevs[i], B_TRUE, VDEV_CONFIG_L2CACHE);
1537         VERIFY(nvlist_add_nvlist_array(sav->sav_config,
1538             ZPOOL_CONFIG_L2CACHE, l2cache, sav->sav_count) == 0);
1539 out:
1540         for (i = 0; i < sav->sav_count; i++)
1541                 nvlist_free(l2cache[i]);
1542         if (sav->sav_count)
1543                 kmem_free(l2cache, sav->sav_count * sizeof (void *));
1544 }
1545 
1546 static int
1547 load_nvlist(spa_t *spa, uint64_t obj, nvlist_t **value)
1548 {
1549         dmu_buf_t *db;
1550         char *packed = NULL;
1551         size_t nvsize = 0;
1552         int error;
1553         *value = NULL;
1554 
1555         VERIFY(0 == dmu_bonus_hold(spa->spa_meta_objset, obj, FTAG, &db));
1556         nvsize = *(uint64_t *)db->db_data;
1557         dmu_buf_rele(db, FTAG);
1558 
1559         packed = kmem_alloc(nvsize, KM_SLEEP);
1560         error = dmu_read(spa->spa_meta_objset, obj, 0, nvsize, packed,
1561             DMU_READ_PREFETCH);
1562         if (error == 0)
1563                 error = nvlist_unpack(packed, nvsize, value, 0);
1564         kmem_free(packed, nvsize);
1565 
1566         return (error);
1567 }
1568 
1569 /*
1570  * Checks to see if the given vdev could not be opened, in which case we post a
1571  * sysevent to notify the autoreplace code that the device has been removed.
1572  */
1573 static void
1574 spa_check_removed(vdev_t *vd)
1575 {
1576         for (int c = 0; c < vd->vdev_children; c++)
1577                 spa_check_removed(vd->vdev_child[c]);
1578 
1579         if (vd->vdev_ops->vdev_op_leaf && vdev_is_dead(vd) &&
1580             !vd->vdev_ishole) {
1581                 zfs_post_autoreplace(vd->vdev_spa, vd);
1582                 spa_event_notify(vd->vdev_spa, vd, ESC_ZFS_VDEV_CHECK);
1583         }
1584 }
1585 
1586 /*
1587  * Validate the current config against the MOS config
1588  */
1589 static boolean_t
1590 spa_config_valid(spa_t *spa, nvlist_t *config)
1591 {
1592         vdev_t *mrvd, *rvd = spa->spa_root_vdev;
1593         nvlist_t *nv;
1594 
1595         VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nv) == 0);
1596 
1597         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1598         VERIFY(spa_config_parse(spa, &mrvd, nv, NULL, 0, VDEV_ALLOC_LOAD) == 0);
1599 
1600         ASSERT3U(rvd->vdev_children, ==, mrvd->vdev_children);
1601 
1602         /*
1603          * If we're doing a normal import, then build up any additional
1604          * diagnostic information about missing devices in this config.
1605          * We'll pass this up to the user for further processing.
1606          */
1607         if (!(spa->spa_import_flags & ZFS_IMPORT_MISSING_LOG)) {
1608                 nvlist_t **child, *nv;
1609                 uint64_t idx = 0;
1610 
1611                 child = kmem_alloc(rvd->vdev_children * sizeof (nvlist_t **),
1612                     KM_SLEEP);
1613                 VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1614 
1615                 for (int c = 0; c < rvd->vdev_children; c++) {
1616                         vdev_t *tvd = rvd->vdev_child[c];
1617                         vdev_t *mtvd  = mrvd->vdev_child[c];
1618 
1619                         if (tvd->vdev_ops == &vdev_missing_ops &&
1620                             mtvd->vdev_ops != &vdev_missing_ops &&
1621                             mtvd->vdev_islog)
1622                                 child[idx++] = vdev_config_generate(spa, mtvd,
1623                                     B_FALSE, 0);
1624                 }
1625 
1626                 if (idx) {
1627                         VERIFY(nvlist_add_nvlist_array(nv,
1628                             ZPOOL_CONFIG_CHILDREN, child, idx) == 0);
1629                         VERIFY(nvlist_add_nvlist(spa->spa_load_info,
1630                             ZPOOL_CONFIG_MISSING_DEVICES, nv) == 0);
1631 
1632                         for (int i = 0; i < idx; i++)
1633                                 nvlist_free(child[i]);
1634                 }
1635                 nvlist_free(nv);
1636                 kmem_free(child, rvd->vdev_children * sizeof (char **));
1637         }
1638 
1639         /*
1640          * Compare the root vdev tree with the information we have
1641          * from the MOS config (mrvd). Check each top-level vdev
1642          * with the corresponding MOS config top-level (mtvd).
1643          */
1644         for (int c = 0; c < rvd->vdev_children; c++) {
1645                 vdev_t *tvd = rvd->vdev_child[c];
1646                 vdev_t *mtvd  = mrvd->vdev_child[c];
1647 
1648                 /*
1649                  * Resolve any "missing" vdevs in the current configuration.
1650                  * If we find that the MOS config has more accurate information
1651                  * about the top-level vdev then use that vdev instead.
1652                  */
1653                 if (tvd->vdev_ops == &vdev_missing_ops &&
1654                     mtvd->vdev_ops != &vdev_missing_ops) {
1655 
1656                         if (!(spa->spa_import_flags & ZFS_IMPORT_MISSING_LOG))
1657                                 continue;
1658 
1659                         /*
1660                          * Device specific actions.
1661                          */
1662                         if (mtvd->vdev_islog) {
1663                                 spa_set_log_state(spa, SPA_LOG_CLEAR);
1664                         } else {
1665                                 /*
1666                                  * XXX - once we have 'readonly' pool
1667                                  * support we should be able to handle
1668                                  * missing data devices by transitioning
1669                                  * the pool to readonly.
1670                                  */
1671                                 continue;
1672                         }
1673 
1674                         /*
1675                          * Swap the missing vdev with the data we were
1676                          * able to obtain from the MOS config.
1677                          */
1678                         vdev_remove_child(rvd, tvd);
1679                         vdev_remove_child(mrvd, mtvd);
1680 
1681                         vdev_add_child(rvd, mtvd);
1682                         vdev_add_child(mrvd, tvd);
1683 
1684                         spa_config_exit(spa, SCL_ALL, FTAG);
1685                         vdev_load(mtvd);
1686                         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1687 
1688                         vdev_reopen(rvd);
1689                 } else if (mtvd->vdev_islog) {
1690                         /*
1691                          * Load the slog device's state from the MOS config
1692                          * since it's possible that the label does not
1693                          * contain the most up-to-date information.
1694                          */
1695                         vdev_load_log_state(tvd, mtvd);
1696                         vdev_reopen(tvd);
1697                 }
1698         }
1699         vdev_free(mrvd);
1700         spa_config_exit(spa, SCL_ALL, FTAG);
1701 
1702         /*
1703          * Ensure we were able to validate the config.
1704          */
1705         return (rvd->vdev_guid_sum == spa->spa_uberblock.ub_guid_sum);
1706 }
1707 
1708 /*
1709  * Check for missing log devices
1710  */
1711 static boolean_t
1712 spa_check_logs(spa_t *spa)
1713 {
1714         boolean_t rv = B_FALSE;
1715 
1716         switch (spa->spa_log_state) {
1717         case SPA_LOG_MISSING:
1718                 /* need to recheck in case slog has been restored */
1719         case SPA_LOG_UNKNOWN:
1720                 rv = (dmu_objset_find(spa->spa_name, zil_check_log_chain,
1721                     NULL, DS_FIND_CHILDREN) != 0);
1722                 if (rv)
1723                         spa_set_log_state(spa, SPA_LOG_MISSING);
1724                 break;
1725         }
1726         return (rv);
1727 }
1728 
1729 static boolean_t
1730 spa_passivate_log(spa_t *spa)
1731 {
1732         vdev_t *rvd = spa->spa_root_vdev;
1733         boolean_t slog_found = B_FALSE;
1734 
1735         ASSERT(spa_config_held(spa, SCL_ALLOC, RW_WRITER));
1736 
1737         if (!spa_has_slogs(spa))
1738                 return (B_FALSE);
1739 
1740         for (int c = 0; c < rvd->vdev_children; c++) {
1741                 vdev_t *tvd = rvd->vdev_child[c];
1742                 metaslab_group_t *mg = tvd->vdev_mg;
1743 
1744                 if (tvd->vdev_islog) {
1745                         metaslab_group_passivate(mg);
1746                         slog_found = B_TRUE;
1747                 }
1748         }
1749 
1750         return (slog_found);
1751 }
1752 
1753 static void
1754 spa_activate_log(spa_t *spa)
1755 {
1756         vdev_t *rvd = spa->spa_root_vdev;
1757 
1758         ASSERT(spa_config_held(spa, SCL_ALLOC, RW_WRITER));
1759 
1760         for (int c = 0; c < rvd->vdev_children; c++) {
1761                 vdev_t *tvd = rvd->vdev_child[c];
1762                 metaslab_group_t *mg = tvd->vdev_mg;
1763 
1764                 if (tvd->vdev_islog)
1765                         metaslab_group_activate(mg);
1766         }
1767 }
1768 
1769 int
1770 spa_offline_log(spa_t *spa)
1771 {
1772         int error;
1773 
1774         error = dmu_objset_find(spa_name(spa), zil_vdev_offline,
1775             NULL, DS_FIND_CHILDREN);
1776         if (error == 0) {
1777                 /*
1778                  * We successfully offlined the log device, sync out the
1779                  * current txg so that the "stubby" block can be removed
1780                  * by zil_sync().
1781                  */
1782                 txg_wait_synced(spa->spa_dsl_pool, 0);
1783         }
1784         return (error);
1785 }
1786 
1787 static void
1788 spa_aux_check_removed(spa_aux_vdev_t *sav)
1789 {
1790         for (int i = 0; i < sav->sav_count; i++)
1791                 spa_check_removed(sav->sav_vdevs[i]);
1792 }
1793 
1794 void
1795 spa_claim_notify(zio_t *zio)
1796 {
1797         spa_t *spa = zio->io_spa;
1798 
1799         if (zio->io_error)
1800                 return;
1801 
1802         mutex_enter(&spa->spa_props_lock);       /* any mutex will do */
1803         if (spa->spa_claim_max_txg < zio->io_bp->blk_birth)
1804                 spa->spa_claim_max_txg = zio->io_bp->blk_birth;
1805         mutex_exit(&spa->spa_props_lock);
1806 }
1807 
1808 typedef struct spa_load_error {
1809         uint64_t        sle_meta_count;
1810         uint64_t        sle_data_count;
1811 } spa_load_error_t;
1812 
1813 static void
1814 spa_load_verify_done(zio_t *zio)
1815 {
1816         blkptr_t *bp = zio->io_bp;
1817         spa_load_error_t *sle = zio->io_private;
1818         dmu_object_type_t type = BP_GET_TYPE(bp);
1819         int error = zio->io_error;
1820 
1821         if (error) {
1822                 if ((BP_GET_LEVEL(bp) != 0 || DMU_OT_IS_METADATA(type)) &&
1823                     type != DMU_OT_INTENT_LOG)
1824                         atomic_add_64(&sle->sle_meta_count, 1);
1825                 else
1826                         atomic_add_64(&sle->sle_data_count, 1);
1827         }
1828         zio_data_buf_free(zio->io_data, zio->io_size);
1829 }
1830 
1831 /*ARGSUSED*/
1832 static int
1833 spa_load_verify_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
1834     const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
1835 {
1836         if (bp != NULL) {
1837                 zio_t *rio = arg;
1838                 size_t size = BP_GET_PSIZE(bp);
1839                 void *data = zio_data_buf_alloc(size);
1840 
1841                 zio_nowait(zio_read(rio, spa, bp, data, size,
1842                     spa_load_verify_done, rio->io_private, ZIO_PRIORITY_SCRUB,
1843                     ZIO_FLAG_SPECULATIVE | ZIO_FLAG_CANFAIL |
1844                     ZIO_FLAG_SCRUB | ZIO_FLAG_RAW, zb));
1845         }
1846         return (0);
1847 }
1848 
1849 static int
1850 spa_load_verify(spa_t *spa)
1851 {
1852         zio_t *rio;
1853         spa_load_error_t sle = { 0 };
1854         zpool_rewind_policy_t policy;
1855         boolean_t verify_ok = B_FALSE;
1856         int error;
1857 
1858         zpool_get_rewind_policy(spa->spa_config, &policy);
1859 
1860         if (policy.zrp_request & ZPOOL_NEVER_REWIND)
1861                 return (0);
1862 
1863         rio = zio_root(spa, NULL, &sle,
1864             ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE);
1865 
1866         error = traverse_pool(spa, spa->spa_verify_min_txg,
1867             TRAVERSE_PRE | TRAVERSE_PREFETCH, spa_load_verify_cb, rio);
1868 
1869         (void) zio_wait(rio);
1870 
1871         spa->spa_load_meta_errors = sle.sle_meta_count;
1872         spa->spa_load_data_errors = sle.sle_data_count;
1873 
1874         if (!error && sle.sle_meta_count <= policy.zrp_maxmeta &&
1875             sle.sle_data_count <= policy.zrp_maxdata) {
1876                 int64_t loss = 0;
1877 
1878                 verify_ok = B_TRUE;
1879                 spa->spa_load_txg = spa->spa_uberblock.ub_txg;
1880                 spa->spa_load_txg_ts = spa->spa_uberblock.ub_timestamp;
1881 
1882                 loss = spa->spa_last_ubsync_txg_ts - spa->spa_load_txg_ts;
1883                 VERIFY(nvlist_add_uint64(spa->spa_load_info,
1884                     ZPOOL_CONFIG_LOAD_TIME, spa->spa_load_txg_ts) == 0);
1885                 VERIFY(nvlist_add_int64(spa->spa_load_info,
1886                     ZPOOL_CONFIG_REWIND_TIME, loss) == 0);
1887                 VERIFY(nvlist_add_uint64(spa->spa_load_info,
1888                     ZPOOL_CONFIG_LOAD_DATA_ERRORS, sle.sle_data_count) == 0);
1889         } else {
1890                 spa->spa_load_max_txg = spa->spa_uberblock.ub_txg;
1891         }
1892 
1893         if (error) {
1894                 if (error != ENXIO && error != EIO)
1895                         error = SET_ERROR(EIO);
1896                 return (error);
1897         }
1898 
1899         return (verify_ok ? 0 : EIO);
1900 }
1901 
1902 /*
1903  * Find a value in the pool props object.
1904  */
1905 static void
1906 spa_prop_find(spa_t *spa, zpool_prop_t prop, uint64_t *val)
1907 {
1908         (void) zap_lookup(spa->spa_meta_objset, spa->spa_pool_props_object,
1909             zpool_prop_to_name(prop), sizeof (uint64_t), 1, val);
1910 }
1911 
1912 /*
1913  * Find a value in the pool directory object.
1914  */
1915 static int
1916 spa_dir_prop(spa_t *spa, const char *name, uint64_t *val)
1917 {
1918         return (zap_lookup(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
1919             name, sizeof (uint64_t), 1, val));
1920 }
1921 
1922 static int
1923 spa_vdev_err(vdev_t *vdev, vdev_aux_t aux, int err)
1924 {
1925         vdev_set_state(vdev, B_TRUE, VDEV_STATE_CANT_OPEN, aux);
1926         return (err);
1927 }
1928 
1929 /*
1930  * Fix up config after a partly-completed split.  This is done with the
1931  * ZPOOL_CONFIG_SPLIT nvlist.  Both the splitting pool and the split-off
1932  * pool have that entry in their config, but only the splitting one contains
1933  * a list of all the guids of the vdevs that are being split off.
1934  *
1935  * This function determines what to do with that list: either rejoin
1936  * all the disks to the pool, or complete the splitting process.  To attempt
1937  * the rejoin, each disk that is offlined is marked online again, and
1938  * we do a reopen() call.  If the vdev label for every disk that was
1939  * marked online indicates it was successfully split off (VDEV_AUX_SPLIT_POOL)
1940  * then we call vdev_split() on each disk, and complete the split.
1941  *
1942  * Otherwise we leave the config alone, with all the vdevs in place in
1943  * the original pool.
1944  */
1945 static void
1946 spa_try_repair(spa_t *spa, nvlist_t *config)
1947 {
1948         uint_t extracted;
1949         uint64_t *glist;
1950         uint_t i, gcount;
1951         nvlist_t *nvl;
1952         vdev_t **vd;
1953         boolean_t attempt_reopen;
1954 
1955         if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_SPLIT, &nvl) != 0)
1956                 return;
1957 
1958         /* check that the config is complete */
1959         if (nvlist_lookup_uint64_array(nvl, ZPOOL_CONFIG_SPLIT_LIST,
1960             &glist, &gcount) != 0)
1961                 return;
1962 
1963         vd = kmem_zalloc(gcount * sizeof (vdev_t *), KM_SLEEP);
1964 
1965         /* attempt to online all the vdevs & validate */
1966         attempt_reopen = B_TRUE;
1967         for (i = 0; i < gcount; i++) {
1968                 if (glist[i] == 0)      /* vdev is hole */
1969                         continue;
1970 
1971                 vd[i] = spa_lookup_by_guid(spa, glist[i], B_FALSE);
1972                 if (vd[i] == NULL) {
1973                         /*
1974                          * Don't bother attempting to reopen the disks;
1975                          * just do the split.
1976                          */
1977                         attempt_reopen = B_FALSE;
1978                 } else {
1979                         /* attempt to re-online it */
1980                         vd[i]->vdev_offline = B_FALSE;
1981                 }
1982         }
1983 
1984         if (attempt_reopen) {
1985                 vdev_reopen(spa->spa_root_vdev);
1986 
1987                 /* check each device to see what state it's in */
1988                 for (extracted = 0, i = 0; i < gcount; i++) {
1989                         if (vd[i] != NULL &&
1990                             vd[i]->vdev_stat.vs_aux != VDEV_AUX_SPLIT_POOL)
1991                                 break;
1992                         ++extracted;
1993                 }
1994         }
1995 
1996         /*
1997          * If every disk has been moved to the new pool, or if we never
1998          * even attempted to look at them, then we split them off for
1999          * good.
2000          */
2001         if (!attempt_reopen || gcount == extracted) {
2002                 for (i = 0; i < gcount; i++)
2003                         if (vd[i] != NULL)
2004                                 vdev_split(vd[i]);
2005                 vdev_reopen(spa->spa_root_vdev);
2006         }
2007 
2008         kmem_free(vd, gcount * sizeof (vdev_t *));
2009 }
2010 
2011 static int
2012 spa_load(spa_t *spa, spa_load_state_t state, spa_import_type_t type,
2013     boolean_t mosconfig)
2014 {
2015         nvlist_t *config = spa->spa_config;
2016         char *ereport = FM_EREPORT_ZFS_POOL;
2017         char *comment;
2018         int error;
2019         uint64_t pool_guid;
2020         nvlist_t *nvl;
2021 
2022         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID, &pool_guid))
2023                 return (SET_ERROR(EINVAL));
2024 
2025         ASSERT(spa->spa_comment == NULL);
2026         if (nvlist_lookup_string(config, ZPOOL_CONFIG_COMMENT, &comment) == 0)
2027                 spa->spa_comment = spa_strdup(comment);
2028 
2029         /*
2030          * Versioning wasn't explicitly added to the label until later, so if
2031          * it's not present treat it as the initial version.
2032          */
2033         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_VERSION,
2034             &spa->spa_ubsync.ub_version) != 0)
2035                 spa->spa_ubsync.ub_version = SPA_VERSION_INITIAL;
2036 
2037         (void) nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
2038             &spa->spa_config_txg);
2039 
2040         if ((state == SPA_LOAD_IMPORT || state == SPA_LOAD_TRYIMPORT) &&
2041             spa_guid_exists(pool_guid, 0)) {
2042                 error = SET_ERROR(EEXIST);
2043         } else {
2044                 spa->spa_config_guid = pool_guid;
2045 
2046                 if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_SPLIT,
2047                     &nvl) == 0) {
2048                         VERIFY(nvlist_dup(nvl, &spa->spa_config_splitting,
2049                             KM_SLEEP) == 0);
2050                 }
2051 
2052                 nvlist_free(spa->spa_load_info);
2053                 spa->spa_load_info = fnvlist_alloc();
2054 
2055                 gethrestime(&spa->spa_loaded_ts);
2056                 error = spa_load_impl(spa, pool_guid, config, state, type,
2057                     mosconfig, &ereport);
2058         }
2059 
2060         spa->spa_minref = refcount_count(&spa->spa_refcount);
2061         if (error) {
2062                 if (error != EEXIST) {
2063                         spa->spa_loaded_ts.tv_sec = 0;
2064                         spa->spa_loaded_ts.tv_nsec = 0;
2065                 }
2066                 if (error != EBADF) {
2067                         zfs_ereport_post(ereport, spa, NULL, NULL, 0, 0);
2068                 }
2069         }
2070         spa->spa_load_state = error ? SPA_LOAD_ERROR : SPA_LOAD_NONE;
2071         spa->spa_ena = 0;
2072 
2073         return (error);
2074 }
2075 
2076 /*
2077  * Load an existing storage pool, using the pool's builtin spa_config as a
2078  * source of configuration information.
2079  */
2080 static int
2081 spa_load_impl(spa_t *spa, uint64_t pool_guid, nvlist_t *config,
2082     spa_load_state_t state, spa_import_type_t type, boolean_t mosconfig,
2083     char **ereport)
2084 {
2085         int error = 0;
2086         nvlist_t *nvroot = NULL;
2087         nvlist_t *label;
2088         vdev_t *rvd;
2089         uberblock_t *ub = &spa->spa_uberblock;
2090         uint64_t children, config_cache_txg = spa->spa_config_txg;
2091         int orig_mode = spa->spa_mode;
2092         int parse;
2093         uint64_t obj;
2094         boolean_t missing_feat_write = B_FALSE;
2095 
2096         /*
2097          * If this is an untrusted config, access the pool in read-only mode.
2098          * This prevents things like resilvering recently removed devices.
2099          */
2100         if (!mosconfig)
2101                 spa->spa_mode = FREAD;
2102 
2103         ASSERT(MUTEX_HELD(&spa_namespace_lock));
2104 
2105         spa->spa_load_state = state;
2106 
2107         if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nvroot))
2108                 return (SET_ERROR(EINVAL));
2109 
2110         parse = (type == SPA_IMPORT_EXISTING ?
2111             VDEV_ALLOC_LOAD : VDEV_ALLOC_SPLIT);
2112 
2113         /*
2114          * Create "The Godfather" zio to hold all async IOs
2115          */
2116         spa->spa_async_zio_root = zio_root(spa, NULL, NULL,
2117             ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_GODFATHER);
2118 
2119         /*
2120          * Parse the configuration into a vdev tree.  We explicitly set the
2121          * value that will be returned by spa_version() since parsing the
2122          * configuration requires knowing the version number.
2123          */
2124         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2125         error = spa_config_parse(spa, &rvd, nvroot, NULL, 0, parse);
2126         spa_config_exit(spa, SCL_ALL, FTAG);
2127 
2128         if (error != 0)
2129                 return (error);
2130 
2131         ASSERT(spa->spa_root_vdev == rvd);
2132 
2133         if (type != SPA_IMPORT_ASSEMBLE) {
2134                 ASSERT(spa_guid(spa) == pool_guid);
2135         }
2136 
2137         /*
2138          * Try to open all vdevs, loading each label in the process.
2139          */
2140         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2141         error = vdev_open(rvd);
2142         spa_config_exit(spa, SCL_ALL, FTAG);
2143         if (error != 0)
2144                 return (error);
2145 
2146         /*
2147          * We need to validate the vdev labels against the configuration that
2148          * we have in hand, which is dependent on the setting of mosconfig. If
2149          * mosconfig is true then we're validating the vdev labels based on
2150          * that config.  Otherwise, we're validating against the cached config
2151          * (zpool.cache) that was read when we loaded the zfs module, and then
2152          * later we will recursively call spa_load() and validate against
2153          * the vdev config.
2154          *
2155          * If we're assembling a new pool that's been split off from an
2156          * existing pool, the labels haven't yet been updated so we skip
2157          * validation for now.
2158          */
2159         if (type != SPA_IMPORT_ASSEMBLE) {
2160                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2161                 error = vdev_validate(rvd, mosconfig);
2162                 spa_config_exit(spa, SCL_ALL, FTAG);
2163 
2164                 if (error != 0)
2165                         return (error);
2166 
2167                 if (rvd->vdev_state <= VDEV_STATE_CANT_OPEN)
2168                         return (SET_ERROR(ENXIO));
2169         }
2170 
2171         /*
2172          * Find the best uberblock.
2173          */
2174         vdev_uberblock_load(rvd, ub, &label);
2175 
2176         /*
2177          * If we weren't able to find a single valid uberblock, return failure.
2178          */
2179         if (ub->ub_txg == 0) {
2180                 nvlist_free(label);
2181                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, ENXIO));
2182         }
2183 
2184         /*
2185          * If the pool has an unsupported version we can't open it.
2186          */
2187         if (!SPA_VERSION_IS_SUPPORTED(ub->ub_version)) {
2188                 nvlist_free(label);
2189                 return (spa_vdev_err(rvd, VDEV_AUX_VERSION_NEWER, ENOTSUP));
2190         }
2191 
2192         if (ub->ub_version >= SPA_VERSION_FEATURES) {
2193                 nvlist_t *features;
2194 
2195                 /*
2196                  * If we weren't able to find what's necessary for reading the
2197                  * MOS in the label, return failure.
2198                  */
2199                 if (label == NULL || nvlist_lookup_nvlist(label,
2200                     ZPOOL_CONFIG_FEATURES_FOR_READ, &features) != 0) {
2201                         nvlist_free(label);
2202                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA,
2203                             ENXIO));
2204                 }
2205 
2206                 /*
2207                  * Update our in-core representation with the definitive values
2208                  * from the label.
2209                  */
2210                 nvlist_free(spa->spa_label_features);
2211                 VERIFY(nvlist_dup(features, &spa->spa_label_features, 0) == 0);
2212         }
2213 
2214         nvlist_free(label);
2215 
2216         /*
2217          * Look through entries in the label nvlist's features_for_read. If
2218          * there is a feature listed there which we don't understand then we
2219          * cannot open a pool.
2220          */
2221         if (ub->ub_version >= SPA_VERSION_FEATURES) {
2222                 nvlist_t *unsup_feat;
2223 
2224                 VERIFY(nvlist_alloc(&unsup_feat, NV_UNIQUE_NAME, KM_SLEEP) ==
2225                     0);
2226 
2227                 for (nvpair_t *nvp = nvlist_next_nvpair(spa->spa_label_features,
2228                     NULL); nvp != NULL;
2229                     nvp = nvlist_next_nvpair(spa->spa_label_features, nvp)) {
2230                         if (!zfeature_is_supported(nvpair_name(nvp))) {
2231                                 VERIFY(nvlist_add_string(unsup_feat,
2232                                     nvpair_name(nvp), "") == 0);
2233                         }
2234                 }
2235 
2236                 if (!nvlist_empty(unsup_feat)) {
2237                         VERIFY(nvlist_add_nvlist(spa->spa_load_info,
2238                             ZPOOL_CONFIG_UNSUP_FEAT, unsup_feat) == 0);
2239                         nvlist_free(unsup_feat);
2240                         return (spa_vdev_err(rvd, VDEV_AUX_UNSUP_FEAT,
2241                             ENOTSUP));
2242                 }
2243 
2244                 nvlist_free(unsup_feat);
2245         }
2246 
2247         /*
2248          * If the vdev guid sum doesn't match the uberblock, we have an
2249          * incomplete configuration.  We first check to see if the pool
2250          * is aware of the complete config (i.e ZPOOL_CONFIG_VDEV_CHILDREN).
2251          * If it is, defer the vdev_guid_sum check till later so we
2252          * can handle missing vdevs.
2253          */
2254         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN,
2255             &children) != 0 && mosconfig && type != SPA_IMPORT_ASSEMBLE &&
2256             rvd->vdev_guid_sum != ub->ub_guid_sum)
2257                 return (spa_vdev_err(rvd, VDEV_AUX_BAD_GUID_SUM, ENXIO));
2258 
2259         if (type != SPA_IMPORT_ASSEMBLE && spa->spa_config_splitting) {
2260                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2261                 spa_try_repair(spa, config);
2262                 spa_config_exit(spa, SCL_ALL, FTAG);
2263                 nvlist_free(spa->spa_config_splitting);
2264                 spa->spa_config_splitting = NULL;
2265         }
2266 
2267         /*
2268          * Initialize internal SPA structures.
2269          */
2270         spa->spa_state = POOL_STATE_ACTIVE;
2271         spa->spa_ubsync = spa->spa_uberblock;
2272         spa->spa_verify_min_txg = spa->spa_extreme_rewind ?
2273             TXG_INITIAL - 1 : spa_last_synced_txg(spa) - TXG_DEFER_SIZE - 1;
2274         spa->spa_first_txg = spa->spa_last_ubsync_txg ?
2275             spa->spa_last_ubsync_txg : spa_last_synced_txg(spa) + 1;
2276         spa->spa_claim_max_txg = spa->spa_first_txg;
2277         spa->spa_prev_software_version = ub->ub_software_version;
2278 
2279         error = dsl_pool_init(spa, spa->spa_first_txg, &spa->spa_dsl_pool);
2280         if (error)
2281                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2282         spa->spa_meta_objset = spa->spa_dsl_pool->dp_meta_objset;
2283 
2284         if (spa_dir_prop(spa, DMU_POOL_CONFIG, &spa->spa_config_object) != 0)
2285                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2286 
2287         if (spa_version(spa) >= SPA_VERSION_FEATURES) {
2288                 boolean_t missing_feat_read = B_FALSE;
2289                 nvlist_t *unsup_feat, *enabled_feat;
2290 
2291                 if (spa_dir_prop(spa, DMU_POOL_FEATURES_FOR_READ,
2292                     &spa->spa_feat_for_read_obj) != 0) {
2293                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2294                 }
2295 
2296                 if (spa_dir_prop(spa, DMU_POOL_FEATURES_FOR_WRITE,
2297                     &spa->spa_feat_for_write_obj) != 0) {
2298                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2299                 }
2300 
2301                 if (spa_dir_prop(spa, DMU_POOL_FEATURE_DESCRIPTIONS,
2302                     &spa->spa_feat_desc_obj) != 0) {
2303                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2304                 }
2305 
2306                 enabled_feat = fnvlist_alloc();
2307                 unsup_feat = fnvlist_alloc();
2308 
2309                 if (!spa_features_check(spa, B_FALSE,
2310                     unsup_feat, enabled_feat))
2311                         missing_feat_read = B_TRUE;
2312 
2313                 if (spa_writeable(spa) || state == SPA_LOAD_TRYIMPORT) {
2314                         if (!spa_features_check(spa, B_TRUE,
2315                             unsup_feat, enabled_feat)) {
2316                                 missing_feat_write = B_TRUE;
2317                         }
2318                 }
2319 
2320                 fnvlist_add_nvlist(spa->spa_load_info,
2321                     ZPOOL_CONFIG_ENABLED_FEAT, enabled_feat);
2322 
2323                 if (!nvlist_empty(unsup_feat)) {
2324                         fnvlist_add_nvlist(spa->spa_load_info,
2325                             ZPOOL_CONFIG_UNSUP_FEAT, unsup_feat);
2326                 }
2327 
2328                 fnvlist_free(enabled_feat);
2329                 fnvlist_free(unsup_feat);
2330 
2331                 if (!missing_feat_read) {
2332                         fnvlist_add_boolean(spa->spa_load_info,
2333                             ZPOOL_CONFIG_CAN_RDONLY);
2334                 }
2335 
2336                 /*
2337                  * If the state is SPA_LOAD_TRYIMPORT, our objective is
2338                  * twofold: to determine whether the pool is available for
2339                  * import in read-write mode and (if it is not) whether the
2340                  * pool is available for import in read-only mode. If the pool
2341                  * is available for import in read-write mode, it is displayed
2342                  * as available in userland; if it is not available for import
2343                  * in read-only mode, it is displayed as unavailable in
2344                  * userland. If the pool is available for import in read-only
2345                  * mode but not read-write mode, it is displayed as unavailable
2346                  * in userland with a special note that the pool is actually
2347                  * available for open in read-only mode.
2348                  *
2349                  * As a result, if the state is SPA_LOAD_TRYIMPORT and we are
2350                  * missing a feature for write, we must first determine whether
2351                  * the pool can be opened read-only before returning to
2352                  * userland in order to know whether to display the
2353                  * abovementioned note.
2354                  */
2355                 if (missing_feat_read || (missing_feat_write &&
2356                     spa_writeable(spa))) {
2357                         return (spa_vdev_err(rvd, VDEV_AUX_UNSUP_FEAT,
2358                             ENOTSUP));
2359                 }
2360         }
2361 
2362         spa->spa_is_initializing = B_TRUE;
2363         error = dsl_pool_open(spa->spa_dsl_pool);
2364         spa->spa_is_initializing = B_FALSE;
2365         if (error != 0)
2366                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2367 
2368         if (!mosconfig) {
2369                 uint64_t hostid;
2370                 nvlist_t *policy = NULL, *nvconfig;
2371 
2372                 if (load_nvlist(spa, spa->spa_config_object, &nvconfig) != 0)
2373                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2374 
2375                 if (!spa_is_root(spa) && nvlist_lookup_uint64(nvconfig,
2376                     ZPOOL_CONFIG_HOSTID, &hostid) == 0) {
2377                         char *hostname;
2378                         unsigned long myhostid = 0;
2379 
2380                         VERIFY(nvlist_lookup_string(nvconfig,
2381                             ZPOOL_CONFIG_HOSTNAME, &hostname) == 0);
2382 
2383 #ifdef  _KERNEL
2384                         myhostid = zone_get_hostid(NULL);
2385 #else   /* _KERNEL */
2386                         /*
2387                          * We're emulating the system's hostid in userland, so
2388                          * we can't use zone_get_hostid().
2389                          */
2390                         (void) ddi_strtoul(hw_serial, NULL, 10, &myhostid);
2391 #endif  /* _KERNEL */
2392                         if (hostid != 0 && myhostid != 0 &&
2393                             hostid != myhostid) {
2394                                 nvlist_free(nvconfig);
2395                                 cmn_err(CE_WARN, "pool '%s' could not be "
2396                                     "loaded as it was last accessed by "
2397                                     "another system (host: %s hostid: 0x%lx). "
2398                                     "See: http://illumos.org/msg/ZFS-8000-EY",
2399                                     spa_name(spa), hostname,
2400                                     (unsigned long)hostid);
2401                                 return (SET_ERROR(EBADF));
2402                         }
2403                 }
2404                 if (nvlist_lookup_nvlist(spa->spa_config,
2405                     ZPOOL_REWIND_POLICY, &policy) == 0)
2406                         VERIFY(nvlist_add_nvlist(nvconfig,
2407                             ZPOOL_REWIND_POLICY, policy) == 0);
2408 
2409                 spa_config_set(spa, nvconfig);
2410                 spa_unload(spa);
2411                 spa_deactivate(spa);
2412                 spa_activate(spa, orig_mode);
2413 
2414                 return (spa_load(spa, state, SPA_IMPORT_EXISTING, B_TRUE));
2415         }
2416 
2417         if (spa_dir_prop(spa, DMU_POOL_SYNC_BPOBJ, &obj) != 0)
2418                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2419         error = bpobj_open(&spa->spa_deferred_bpobj, spa->spa_meta_objset, obj);
2420         if (error != 0)
2421                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2422 
2423         /*
2424          * Load the bit that tells us to use the new accounting function
2425          * (raid-z deflation).  If we have an older pool, this will not
2426          * be present.
2427          */
2428         error = spa_dir_prop(spa, DMU_POOL_DEFLATE, &spa->spa_deflate);
2429         if (error != 0 && error != ENOENT)
2430                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2431 
2432         error = spa_dir_prop(spa, DMU_POOL_CREATION_VERSION,
2433             &spa->spa_creation_version);
2434         if (error != 0 && error != ENOENT)
2435                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2436 
2437         /*
2438          * Load the persistent error log.  If we have an older pool, this will
2439          * not be present.
2440          */
2441         error = spa_dir_prop(spa, DMU_POOL_ERRLOG_LAST, &spa->spa_errlog_last);
2442         if (error != 0 && error != ENOENT)
2443                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2444 
2445         error = spa_dir_prop(spa, DMU_POOL_ERRLOG_SCRUB,
2446             &spa->spa_errlog_scrub);
2447         if (error != 0 && error != ENOENT)
2448                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2449 
2450         /*
2451          * Load the history object.  If we have an older pool, this
2452          * will not be present.
2453          */
2454         error = spa_dir_prop(spa, DMU_POOL_HISTORY, &spa->spa_history);
2455         if (error != 0 && error != ENOENT)
2456                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2457 
2458         /*
2459          * If we're assembling the pool from the split-off vdevs of
2460          * an existing pool, we don't want to attach the spares & cache
2461          * devices.
2462          */
2463 
2464         /*
2465          * Load any hot spares for this pool.
2466          */
2467         error = spa_dir_prop(spa, DMU_POOL_SPARES, &spa->spa_spares.sav_object);
2468         if (error != 0 && error != ENOENT)
2469                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2470         if (error == 0 && type != SPA_IMPORT_ASSEMBLE) {
2471                 ASSERT(spa_version(spa) >= SPA_VERSION_SPARES);
2472                 if (load_nvlist(spa, spa->spa_spares.sav_object,
2473                     &spa->spa_spares.sav_config) != 0)
2474                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2475 
2476                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2477                 spa_load_spares(spa);
2478                 spa_config_exit(spa, SCL_ALL, FTAG);
2479         } else if (error == 0) {
2480                 spa->spa_spares.sav_sync = B_TRUE;
2481         }
2482 
2483         /*
2484          * Load any level 2 ARC devices for this pool.
2485          */
2486         error = spa_dir_prop(spa, DMU_POOL_L2CACHE,
2487             &spa->spa_l2cache.sav_object);
2488         if (error != 0 && error != ENOENT)
2489                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2490         if (error == 0 && type != SPA_IMPORT_ASSEMBLE) {
2491                 ASSERT(spa_version(spa) >= SPA_VERSION_L2CACHE);
2492                 if (load_nvlist(spa, spa->spa_l2cache.sav_object,
2493                     &spa->spa_l2cache.sav_config) != 0)
2494                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2495 
2496                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2497                 spa_load_l2cache(spa);
2498                 spa_config_exit(spa, SCL_ALL, FTAG);
2499         } else if (error == 0) {
2500                 spa->spa_l2cache.sav_sync = B_TRUE;
2501         }
2502 
2503         spa->spa_delegation = zpool_prop_default_numeric(ZPOOL_PROP_DELEGATION);
2504 
2505         error = spa_dir_prop(spa, DMU_POOL_PROPS, &spa->spa_pool_props_object);
2506         if (error && error != ENOENT)
2507                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2508 
2509         if (error == 0) {
2510                 uint64_t autoreplace;
2511 
2512                 spa_prop_find(spa, ZPOOL_PROP_BOOTFS, &spa->spa_bootfs);
2513                 spa_prop_find(spa, ZPOOL_PROP_AUTOREPLACE, &autoreplace);
2514                 spa_prop_find(spa, ZPOOL_PROP_DELEGATION, &spa->spa_delegation);
2515                 spa_prop_find(spa, ZPOOL_PROP_FAILUREMODE, &spa->spa_failmode);
2516                 spa_prop_find(spa, ZPOOL_PROP_AUTOEXPAND, &spa->spa_autoexpand);
2517                 spa_prop_find(spa, ZPOOL_PROP_DEDUPDITTO,
2518                     &spa->spa_dedup_ditto);
2519 
2520                 spa->spa_autoreplace = (autoreplace != 0);
2521         }
2522 
2523         /*
2524          * If the 'autoreplace' property is set, then post a resource notifying
2525          * the ZFS DE that it should not issue any faults for unopenable
2526          * devices.  We also iterate over the vdevs, and post a sysevent for any
2527          * unopenable vdevs so that the normal autoreplace handler can take
2528          * over.
2529          */
2530         if (spa->spa_autoreplace && state != SPA_LOAD_TRYIMPORT) {
2531                 spa_check_removed(spa->spa_root_vdev);
2532                 /*
2533                  * For the import case, this is done in spa_import(), because
2534                  * at this point we're using the spare definitions from
2535                  * the MOS config, not necessarily from the userland config.
2536                  */
2537                 if (state != SPA_LOAD_IMPORT) {
2538                         spa_aux_check_removed(&spa->spa_spares);
2539                         spa_aux_check_removed(&spa->spa_l2cache);
2540                 }
2541         }
2542 
2543         /*
2544          * Load the vdev state for all toplevel vdevs.
2545          */
2546         vdev_load(rvd);
2547 
2548         /*
2549          * Propagate the leaf DTLs we just loaded all the way up the tree.
2550          */
2551         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2552         vdev_dtl_reassess(rvd, 0, 0, B_FALSE);
2553         spa_config_exit(spa, SCL_ALL, FTAG);
2554 
2555         /*
2556          * Load the DDTs (dedup tables).
2557          */
2558         error = ddt_load(spa);
2559         if (error != 0)
2560                 return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2561 
2562         spa_update_dspace(spa);
2563 
2564         /*
2565          * Validate the config, using the MOS config to fill in any
2566          * information which might be missing.  If we fail to validate
2567          * the config then declare the pool unfit for use. If we're
2568          * assembling a pool from a split, the log is not transferred
2569          * over.
2570          */
2571         if (type != SPA_IMPORT_ASSEMBLE) {
2572                 nvlist_t *nvconfig;
2573 
2574                 if (load_nvlist(spa, spa->spa_config_object, &nvconfig) != 0)
2575                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, EIO));
2576 
2577                 if (!spa_config_valid(spa, nvconfig)) {
2578                         nvlist_free(nvconfig);
2579                         return (spa_vdev_err(rvd, VDEV_AUX_BAD_GUID_SUM,
2580                             ENXIO));
2581                 }
2582                 nvlist_free(nvconfig);
2583 
2584                 /*
2585                  * Now that we've validated the config, check the state of the
2586                  * root vdev.  If it can't be opened, it indicates one or
2587                  * more toplevel vdevs are faulted.
2588                  */
2589                 if (rvd->vdev_state <= VDEV_STATE_CANT_OPEN)
2590                         return (SET_ERROR(ENXIO));
2591 
2592                 if (spa_check_logs(spa)) {
2593                         *ereport = FM_EREPORT_ZFS_LOG_REPLAY;
2594                         return (spa_vdev_err(rvd, VDEV_AUX_BAD_LOG, ENXIO));
2595                 }
2596         }
2597 
2598         if (missing_feat_write) {
2599                 ASSERT(state == SPA_LOAD_TRYIMPORT);
2600 
2601                 /*
2602                  * At this point, we know that we can open the pool in
2603                  * read-only mode but not read-write mode. We now have enough
2604                  * information and can return to userland.
2605                  */
2606                 return (spa_vdev_err(rvd, VDEV_AUX_UNSUP_FEAT, ENOTSUP));
2607         }
2608 
2609         /*
2610          * We've successfully opened the pool, verify that we're ready
2611          * to start pushing transactions.
2612          */
2613         if (state != SPA_LOAD_TRYIMPORT) {
2614                 if (error = spa_load_verify(spa))
2615                         return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA,
2616                             error));
2617         }
2618 
2619         if (spa_writeable(spa) && (state == SPA_LOAD_RECOVER ||
2620             spa->spa_load_max_txg == UINT64_MAX)) {
2621                 dmu_tx_t *tx;
2622                 int need_update = B_FALSE;
2623 
2624                 ASSERT(state != SPA_LOAD_TRYIMPORT);
2625 
2626                 /*
2627                  * Claim log blocks that haven't been committed yet.
2628                  * This must all happen in a single txg.
2629                  * Note: spa_claim_max_txg is updated by spa_claim_notify(),
2630                  * invoked from zil_claim_log_block()'s i/o done callback.
2631                  * Price of rollback is that we abandon the log.
2632                  */
2633                 spa->spa_claiming = B_TRUE;
2634 
2635                 tx = dmu_tx_create_assigned(spa_get_dsl(spa),
2636                     spa_first_txg(spa));
2637                 (void) dmu_objset_find(spa_name(spa),
2638                     zil_claim, tx, DS_FIND_CHILDREN);
2639                 dmu_tx_commit(tx);
2640 
2641                 spa->spa_claiming = B_FALSE;
2642 
2643                 spa_set_log_state(spa, SPA_LOG_GOOD);
2644                 spa->spa_sync_on = B_TRUE;
2645                 txg_sync_start(spa->spa_dsl_pool);
2646 
2647                 /*
2648                  * Wait for all claims to sync.  We sync up to the highest
2649                  * claimed log block birth time so that claimed log blocks
2650                  * don't appear to be from the future.  spa_claim_max_txg
2651                  * will have been set for us by either zil_check_log_chain()
2652                  * (invoked from spa_check_logs()) or zil_claim() above.
2653                  */
2654                 txg_wait_synced(spa->spa_dsl_pool, spa->spa_claim_max_txg);
2655 
2656                 /*
2657                  * If the config cache is stale, or we have uninitialized
2658                  * metaslabs (see spa_vdev_add()), then update the config.
2659                  *
2660                  * If this is a verbatim import, trust the current
2661                  * in-core spa_config and update the disk labels.
2662                  */
2663                 if (config_cache_txg != spa->spa_config_txg ||
2664                     state == SPA_LOAD_IMPORT ||
2665                     state == SPA_LOAD_RECOVER ||
2666                     (spa->spa_import_flags & ZFS_IMPORT_VERBATIM))
2667                         need_update = B_TRUE;
2668 
2669                 for (int c = 0; c < rvd->vdev_children; c++)
2670                         if (rvd->vdev_child[c]->vdev_ms_array == 0)
2671                                 need_update = B_TRUE;
2672 
2673                 /*
2674                  * Update the config cache asychronously in case we're the
2675                  * root pool, in which case the config cache isn't writable yet.
2676                  */
2677                 if (need_update)
2678                         spa_async_request(spa, SPA_ASYNC_CONFIG_UPDATE);
2679 
2680                 /*
2681                  * Check all DTLs to see if anything needs resilvering.
2682                  */
2683                 if (!dsl_scan_resilvering(spa->spa_dsl_pool) &&
2684                     vdev_resilver_needed(rvd, NULL, NULL))
2685                         spa_async_request(spa, SPA_ASYNC_RESILVER);
2686 
2687                 /*
2688                  * Log the fact that we booted up (so that we can detect if
2689                  * we rebooted in the middle of an operation).
2690                  */
2691                 spa_history_log_version(spa, "open");
2692 
2693                 /*
2694                  * Delete any inconsistent datasets.
2695                  */
2696                 (void) dmu_objset_find(spa_name(spa),
2697                     dsl_destroy_inconsistent, NULL, DS_FIND_CHILDREN);
2698 
2699                 /*
2700                  * Clean up any stale temporary dataset userrefs.
2701                  */
2702                 dsl_pool_clean_tmp_userrefs(spa->spa_dsl_pool);
2703         }
2704 
2705         spa_async_request(spa, SPA_ASYNC_L2CACHE_REBUILD);
2706 
2707         return (0);
2708 }
2709 
2710 static int
2711 spa_load_retry(spa_t *spa, spa_load_state_t state, int mosconfig)
2712 {
2713         int mode = spa->spa_mode;
2714 
2715         spa_unload(spa);
2716         spa_deactivate(spa);
2717 
2718         spa->spa_load_max_txg--;
2719 
2720         spa_activate(spa, mode);
2721         spa_async_suspend(spa);
2722 
2723         return (spa_load(spa, state, SPA_IMPORT_EXISTING, mosconfig));
2724 }
2725 
2726 /*
2727  * If spa_load() fails this function will try loading prior txg's. If
2728  * 'state' is SPA_LOAD_RECOVER and one of these loads succeeds the pool
2729  * will be rewound to that txg. If 'state' is not SPA_LOAD_RECOVER this
2730  * function will not rewind the pool and will return the same error as
2731  * spa_load().
2732  */
2733 static int
2734 spa_load_best(spa_t *spa, spa_load_state_t state, int mosconfig,
2735     uint64_t max_request, int rewind_flags)
2736 {
2737         nvlist_t *loadinfo = NULL;
2738         nvlist_t *config = NULL;
2739         int load_error, rewind_error;
2740         uint64_t safe_rewind_txg;
2741         uint64_t min_txg;
2742 
2743         if (spa->spa_load_txg && state == SPA_LOAD_RECOVER) {
2744                 spa->spa_load_max_txg = spa->spa_load_txg;
2745                 spa_set_log_state(spa, SPA_LOG_CLEAR);
2746         } else {
2747                 spa->spa_load_max_txg = max_request;
2748         }
2749 
2750         load_error = rewind_error = spa_load(spa, state, SPA_IMPORT_EXISTING,
2751             mosconfig);
2752         if (load_error == 0)
2753                 return (0);
2754 
2755         if (spa->spa_root_vdev != NULL)
2756                 config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
2757 
2758         spa->spa_last_ubsync_txg = spa->spa_uberblock.ub_txg;
2759         spa->spa_last_ubsync_txg_ts = spa->spa_uberblock.ub_timestamp;
2760 
2761         if (rewind_flags & ZPOOL_NEVER_REWIND) {
2762                 nvlist_free(config);
2763                 return (load_error);
2764         }
2765 
2766         if (state == SPA_LOAD_RECOVER) {
2767                 /* Price of rolling back is discarding txgs, including log */
2768                 spa_set_log_state(spa, SPA_LOG_CLEAR);
2769         } else {
2770                 /*
2771                  * If we aren't rolling back save the load info from our first
2772                  * import attempt so that we can restore it after attempting
2773                  * to rewind.
2774                  */
2775                 loadinfo = spa->spa_load_info;
2776                 spa->spa_load_info = fnvlist_alloc();
2777         }
2778 
2779         spa->spa_load_max_txg = spa->spa_last_ubsync_txg;
2780         safe_rewind_txg = spa->spa_last_ubsync_txg - TXG_DEFER_SIZE;
2781         min_txg = (rewind_flags & ZPOOL_EXTREME_REWIND) ?
2782             TXG_INITIAL : safe_rewind_txg;
2783 
2784         /*
2785          * Continue as long as we're finding errors, we're still within
2786          * the acceptable rewind range, and we're still finding uberblocks
2787          */
2788         while (rewind_error && spa->spa_uberblock.ub_txg >= min_txg &&
2789             spa->spa_uberblock.ub_txg <= spa->spa_load_max_txg) {
2790                 if (spa->spa_load_max_txg < safe_rewind_txg)
2791                         spa->spa_extreme_rewind = B_TRUE;
2792                 rewind_error = spa_load_retry(spa, state, mosconfig);
2793         }
2794 
2795         spa->spa_extreme_rewind = B_FALSE;
2796         spa->spa_load_max_txg = UINT64_MAX;
2797 
2798         if (config && (rewind_error || state != SPA_LOAD_RECOVER))
2799                 spa_config_set(spa, config);
2800 
2801         if (state == SPA_LOAD_RECOVER) {
2802                 ASSERT3P(loadinfo, ==, NULL);
2803                 return (rewind_error);
2804         } else {
2805                 /* Store the rewind info as part of the initial load info */
2806                 fnvlist_add_nvlist(loadinfo, ZPOOL_CONFIG_REWIND_INFO,
2807                     spa->spa_load_info);
2808 
2809                 /* Restore the initial load info */
2810                 fnvlist_free(spa->spa_load_info);
2811                 spa->spa_load_info = loadinfo;
2812 
2813                 return (load_error);
2814         }
2815 }
2816 
2817 /*
2818  * Pool Open/Import
2819  *
2820  * The import case is identical to an open except that the configuration is sent
2821  * down from userland, instead of grabbed from the configuration cache.  For the
2822  * case of an open, the pool configuration will exist in the
2823  * POOL_STATE_UNINITIALIZED state.
2824  *
2825  * The stats information (gen/count/ustats) is used to gather vdev statistics at
2826  * the same time open the pool, without having to keep around the spa_t in some
2827  * ambiguous state.
2828  */
2829 static int
2830 spa_open_common(const char *pool, spa_t **spapp, void *tag, nvlist_t *nvpolicy,
2831     nvlist_t **config)
2832 {
2833         spa_t *spa;
2834         spa_load_state_t state = SPA_LOAD_OPEN;
2835         int error;
2836         int locked = B_FALSE;
2837 
2838         *spapp = NULL;
2839 
2840         /*
2841          * As disgusting as this is, we need to support recursive calls to this
2842          * function because dsl_dir_open() is called during spa_load(), and ends
2843          * up calling spa_open() again.  The real fix is to figure out how to
2844          * avoid dsl_dir_open() calling this in the first place.
2845          */
2846         if (mutex_owner(&spa_namespace_lock) != curthread) {
2847                 mutex_enter(&spa_namespace_lock);
2848                 locked = B_TRUE;
2849         }
2850 
2851         if ((spa = spa_lookup(pool)) == NULL) {
2852                 if (locked)
2853                         mutex_exit(&spa_namespace_lock);
2854                 return (SET_ERROR(ENOENT));
2855         }
2856 
2857         if (spa->spa_state == POOL_STATE_UNINITIALIZED) {
2858                 zpool_rewind_policy_t policy;
2859 
2860                 zpool_get_rewind_policy(nvpolicy ? nvpolicy : spa->spa_config,
2861                     &policy);
2862                 if (policy.zrp_request & ZPOOL_DO_REWIND)
2863                         state = SPA_LOAD_RECOVER;
2864 
2865                 spa_activate(spa, spa_mode_global);
2866 
2867                 if (state != SPA_LOAD_RECOVER)
2868                         spa->spa_last_ubsync_txg = spa->spa_load_txg = 0;
2869 
2870                 error = spa_load_best(spa, state, B_FALSE, policy.zrp_txg,
2871                     policy.zrp_request);
2872 
2873                 if (error == EBADF) {
2874                         /*
2875                          * If vdev_validate() returns failure (indicated by
2876                          * EBADF), it indicates that one of the vdevs indicates
2877                          * that the pool has been exported or destroyed.  If
2878                          * this is the case, the config cache is out of sync and
2879                          * we should remove the pool from the namespace.
2880                          */
2881                         spa_unload(spa);
2882                         spa_deactivate(spa);
2883                         spa_config_sync(spa, B_TRUE, B_TRUE);
2884                         spa_remove(spa);
2885                         if (locked)
2886                                 mutex_exit(&spa_namespace_lock);
2887                         return (SET_ERROR(ENOENT));
2888                 }
2889 
2890                 if (error) {
2891                         /*
2892                          * We can't open the pool, but we still have useful
2893                          * information: the state of each vdev after the
2894                          * attempted vdev_open().  Return this to the user.
2895                          */
2896                         if (config != NULL && spa->spa_config) {
2897                                 VERIFY(nvlist_dup(spa->spa_config, config,
2898                                     KM_SLEEP) == 0);
2899                                 VERIFY(nvlist_add_nvlist(*config,
2900                                     ZPOOL_CONFIG_LOAD_INFO,
2901                                     spa->spa_load_info) == 0);
2902                         }
2903                         spa_unload(spa);
2904                         spa_deactivate(spa);
2905                         spa->spa_last_open_failed = error;
2906                         if (locked)
2907                                 mutex_exit(&spa_namespace_lock);
2908                         *spapp = NULL;
2909                         return (error);
2910                 }
2911         }
2912 
2913         spa_open_ref(spa, tag);
2914 
2915         if (config != NULL)
2916                 *config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
2917 
2918         /*
2919          * If we've recovered the pool, pass back any information we
2920          * gathered while doing the load.
2921          */
2922         if (state == SPA_LOAD_RECOVER) {
2923                 VERIFY(nvlist_add_nvlist(*config, ZPOOL_CONFIG_LOAD_INFO,
2924                     spa->spa_load_info) == 0);
2925         }
2926 
2927         if (locked) {
2928                 spa->spa_last_open_failed = 0;
2929                 spa->spa_last_ubsync_txg = 0;
2930                 spa->spa_load_txg = 0;
2931                 mutex_exit(&spa_namespace_lock);
2932         }
2933 
2934         *spapp = spa;
2935 
2936         return (0);
2937 }
2938 
2939 int
2940 spa_open_rewind(const char *name, spa_t **spapp, void *tag, nvlist_t *policy,
2941     nvlist_t **config)
2942 {
2943         return (spa_open_common(name, spapp, tag, policy, config));
2944 }
2945 
2946 int
2947 spa_open(const char *name, spa_t **spapp, void *tag)
2948 {
2949         return (spa_open_common(name, spapp, tag, NULL, NULL));
2950 }
2951 
2952 /*
2953  * Lookup the given spa_t, incrementing the inject count in the process,
2954  * preventing it from being exported or destroyed.
2955  */
2956 spa_t *
2957 spa_inject_addref(char *name)
2958 {
2959         spa_t *spa;
2960 
2961         mutex_enter(&spa_namespace_lock);
2962         if ((spa = spa_lookup(name)) == NULL) {
2963                 mutex_exit(&spa_namespace_lock);
2964                 return (NULL);
2965         }
2966         spa->spa_inject_ref++;
2967         mutex_exit(&spa_namespace_lock);
2968 
2969         return (spa);
2970 }
2971 
2972 void
2973 spa_inject_delref(spa_t *spa)
2974 {
2975         mutex_enter(&spa_namespace_lock);
2976         spa->spa_inject_ref--;
2977         mutex_exit(&spa_namespace_lock);
2978 }
2979 
2980 /*
2981  * Add spares device information to the nvlist.
2982  */
2983 static void
2984 spa_add_spares(spa_t *spa, nvlist_t *config)
2985 {
2986         nvlist_t **spares;
2987         uint_t i, nspares;
2988         nvlist_t *nvroot;
2989         uint64_t guid;
2990         vdev_stat_t *vs;
2991         uint_t vsc;
2992         uint64_t pool;
2993 
2994         ASSERT(spa_config_held(spa, SCL_CONFIG, RW_READER));
2995 
2996         if (spa->spa_spares.sav_count == 0)
2997                 return;
2998 
2999         VERIFY(nvlist_lookup_nvlist(config,
3000             ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
3001         VERIFY(nvlist_lookup_nvlist_array(spa->spa_spares.sav_config,
3002             ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0);
3003         if (nspares != 0) {
3004                 VERIFY(nvlist_add_nvlist_array(nvroot,
3005                     ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
3006                 VERIFY(nvlist_lookup_nvlist_array(nvroot,
3007                     ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0);
3008 
3009                 /*
3010                  * Go through and find any spares which have since been
3011                  * repurposed as an active spare.  If this is the case, update
3012                  * their status appropriately.
3013                  */
3014                 for (i = 0; i < nspares; i++) {
3015                         VERIFY(nvlist_lookup_uint64(spares[i],
3016                             ZPOOL_CONFIG_GUID, &guid) == 0);
3017                         if (spa_spare_exists(guid, &pool, NULL) &&
3018                             pool != 0ULL) {
3019                                 VERIFY(nvlist_lookup_uint64_array(
3020                                     spares[i], ZPOOL_CONFIG_VDEV_STATS,
3021                                     (uint64_t **)&vs, &vsc) == 0);
3022                                 vs->vs_state = VDEV_STATE_CANT_OPEN;
3023                                 vs->vs_aux = VDEV_AUX_SPARED;
3024                         }
3025                 }
3026         }
3027 }
3028 
3029 /*
3030  * Add l2cache device information to the nvlist, including vdev stats.
3031  */
3032 static void
3033 spa_add_l2cache(spa_t *spa, nvlist_t *config)
3034 {
3035         nvlist_t **l2cache;
3036         uint_t i, j, nl2cache;
3037         nvlist_t *nvroot;
3038         uint64_t guid;
3039         vdev_t *vd;
3040         vdev_stat_t *vs;
3041         uint_t vsc;
3042 
3043         ASSERT(spa_config_held(spa, SCL_CONFIG, RW_READER));
3044 
3045         if (spa->spa_l2cache.sav_count == 0)
3046                 return;
3047 
3048         VERIFY(nvlist_lookup_nvlist(config,
3049             ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
3050         VERIFY(nvlist_lookup_nvlist_array(spa->spa_l2cache.sav_config,
3051             ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0);
3052         if (nl2cache != 0) {
3053                 VERIFY(nvlist_add_nvlist_array(nvroot,
3054                     ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
3055                 VERIFY(nvlist_lookup_nvlist_array(nvroot,
3056                     ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0);
3057 
3058                 /*
3059                  * Update level 2 cache device stats.
3060                  */
3061 
3062                 for (i = 0; i < nl2cache; i++) {
3063                         VERIFY(nvlist_lookup_uint64(l2cache[i],
3064                             ZPOOL_CONFIG_GUID, &guid) == 0);
3065 
3066                         vd = NULL;
3067                         for (j = 0; j < spa->spa_l2cache.sav_count; j++) {
3068                                 if (guid ==
3069                                     spa->spa_l2cache.sav_vdevs[j]->vdev_guid) {
3070                                         vd = spa->spa_l2cache.sav_vdevs[j];
3071                                         break;
3072                                 }
3073                         }
3074                         ASSERT(vd != NULL);
3075 
3076                         VERIFY(nvlist_lookup_uint64_array(l2cache[i],
3077                             ZPOOL_CONFIG_VDEV_STATS, (uint64_t **)&vs, &vsc)
3078                             == 0);
3079                         vdev_get_stats(vd, vs);
3080                 }
3081         }
3082 }
3083 
3084 static void
3085 spa_add_feature_stats(spa_t *spa, nvlist_t *config)
3086 {
3087         nvlist_t *features;
3088         zap_cursor_t zc;
3089         zap_attribute_t za;
3090 
3091         ASSERT(spa_config_held(spa, SCL_CONFIG, RW_READER));
3092         VERIFY(nvlist_alloc(&features, NV_UNIQUE_NAME, KM_SLEEP) == 0);
3093 
3094         if (spa->spa_feat_for_read_obj != 0) {
3095                 for (zap_cursor_init(&zc, spa->spa_meta_objset,
3096                     spa->spa_feat_for_read_obj);
3097                     zap_cursor_retrieve(&zc, &za) == 0;
3098                     zap_cursor_advance(&zc)) {
3099                         ASSERT(za.za_integer_length == sizeof (uint64_t) &&
3100                             za.za_num_integers == 1);
3101                         VERIFY3U(0, ==, nvlist_add_uint64(features, za.za_name,
3102                             za.za_first_integer));
3103                 }
3104                 zap_cursor_fini(&zc);
3105         }
3106 
3107         if (spa->spa_feat_for_write_obj != 0) {
3108                 for (zap_cursor_init(&zc, spa->spa_meta_objset,
3109                     spa->spa_feat_for_write_obj);
3110                     zap_cursor_retrieve(&zc, &za) == 0;
3111                     zap_cursor_advance(&zc)) {
3112                         ASSERT(za.za_integer_length == sizeof (uint64_t) &&
3113                             za.za_num_integers == 1);
3114                         VERIFY3U(0, ==, nvlist_add_uint64(features, za.za_name,
3115                             za.za_first_integer));
3116                 }
3117                 zap_cursor_fini(&zc);
3118         }
3119 
3120         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_FEATURE_STATS,
3121             features) == 0);
3122         nvlist_free(features);
3123 }
3124 
3125 int
3126 spa_get_stats(const char *name, nvlist_t **config,
3127     char *altroot, size_t buflen)
3128 {
3129         int error;
3130         spa_t *spa;
3131 
3132         *config = NULL;
3133         error = spa_open_common(name, &spa, FTAG, NULL, config);
3134 
3135         if (spa != NULL) {
3136                 /*
3137                  * This still leaves a window of inconsistency where the spares
3138                  * or l2cache devices could change and the config would be
3139                  * self-inconsistent.
3140                  */
3141                 spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
3142 
3143                 if (*config != NULL) {
3144                         uint64_t loadtimes[2];
3145 
3146                         loadtimes[0] = spa->spa_loaded_ts.tv_sec;
3147                         loadtimes[1] = spa->spa_loaded_ts.tv_nsec;
3148                         VERIFY(nvlist_add_uint64_array(*config,
3149                             ZPOOL_CONFIG_LOADED_TIME, loadtimes, 2) == 0);
3150 
3151                         VERIFY(nvlist_add_uint64(*config,
3152                             ZPOOL_CONFIG_ERRCOUNT,
3153                             spa_get_errlog_size(spa)) == 0);
3154 
3155                         if (spa_suspended(spa))
3156                                 VERIFY(nvlist_add_uint64(*config,
3157                                     ZPOOL_CONFIG_SUSPENDED,
3158                                     spa->spa_failmode) == 0);
3159 
3160                         spa_add_spares(spa, *config);
3161                         spa_add_l2cache(spa, *config);
3162                         spa_add_feature_stats(spa, *config);
3163                 }
3164         }
3165 
3166         /*
3167          * We want to get the alternate root even for faulted pools, so we cheat
3168          * and call spa_lookup() directly.
3169          */
3170         if (altroot) {
3171                 if (spa == NULL) {
3172                         mutex_enter(&spa_namespace_lock);
3173                         spa = spa_lookup(name);
3174                         if (spa)
3175                                 spa_altroot(spa, altroot, buflen);
3176                         else
3177                                 altroot[0] = '\0';
3178                         spa = NULL;
3179                         mutex_exit(&spa_namespace_lock);
3180                 } else {
3181                         spa_altroot(spa, altroot, buflen);
3182                 }
3183         }
3184 
3185         if (spa != NULL) {
3186                 spa_config_exit(spa, SCL_CONFIG, FTAG);
3187                 spa_close(spa, FTAG);
3188         }
3189 
3190         return (error);
3191 }
3192 
3193 /*
3194  * Validate that the auxiliary device array is well formed.  We must have an
3195  * array of nvlists, each which describes a valid leaf vdev.  If this is an
3196  * import (mode is VDEV_ALLOC_SPARE), then we allow corrupted spares to be
3197  * specified, as long as they are well-formed.
3198  */
3199 static int
3200 spa_validate_aux_devs(spa_t *spa, nvlist_t *nvroot, uint64_t crtxg, int mode,
3201     spa_aux_vdev_t *sav, const char *config, uint64_t version,
3202     vdev_labeltype_t label)
3203 {
3204         nvlist_t **dev;
3205         uint_t i, ndev;
3206         vdev_t *vd;
3207         int error;
3208 
3209         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
3210 
3211         /*
3212          * It's acceptable to have no devs specified.
3213          */
3214         if (nvlist_lookup_nvlist_array(nvroot, config, &dev, &ndev) != 0)
3215                 return (0);
3216 
3217         if (ndev == 0)
3218                 return (SET_ERROR(EINVAL));
3219 
3220         /*
3221          * Make sure the pool is formatted with a version that supports this
3222          * device type.
3223          */
3224         if (spa_version(spa) < version)
3225                 return (SET_ERROR(ENOTSUP));
3226 
3227         /*
3228          * Set the pending device list so we correctly handle device in-use
3229          * checking.
3230          */
3231         sav->sav_pending = dev;
3232         sav->sav_npending = ndev;
3233 
3234         for (i = 0; i < ndev; i++) {
3235                 if ((error = spa_config_parse(spa, &vd, dev[i], NULL, 0,
3236                     mode)) != 0)
3237                         goto out;
3238 
3239                 if (!vd->vdev_ops->vdev_op_leaf) {
3240                         vdev_free(vd);
3241                         error = SET_ERROR(EINVAL);
3242                         goto out;
3243                 }
3244 
3245                 /*
3246                  * The L2ARC currently only supports disk devices in
3247                  * kernel context.  For user-level testing, we allow it.
3248                  */
3249 #ifdef _KERNEL
3250                 if ((strcmp(config, ZPOOL_CONFIG_L2CACHE) == 0) &&
3251                     strcmp(vd->vdev_ops->vdev_op_type, VDEV_TYPE_DISK) != 0) {
3252                         error = SET_ERROR(ENOTBLK);
3253                         vdev_free(vd);
3254                         goto out;
3255                 }
3256 #endif
3257                 vd->vdev_top = vd;
3258 
3259                 if ((error = vdev_open(vd)) == 0 &&
3260                     (error = vdev_label_init(vd, crtxg, label)) == 0) {
3261                         VERIFY(nvlist_add_uint64(dev[i], ZPOOL_CONFIG_GUID,
3262                             vd->vdev_guid) == 0);
3263                 }
3264 
3265                 vdev_free(vd);
3266 
3267                 if (error &&
3268                     (mode != VDEV_ALLOC_SPARE && mode != VDEV_ALLOC_L2CACHE))
3269                         goto out;
3270                 else
3271                         error = 0;
3272         }
3273 
3274 out:
3275         sav->sav_pending = NULL;
3276         sav->sav_npending = 0;
3277         return (error);
3278 }
3279 
3280 static int
3281 spa_validate_aux(spa_t *spa, nvlist_t *nvroot, uint64_t crtxg, int mode)
3282 {
3283         int error;
3284 
3285         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
3286 
3287         if ((error = spa_validate_aux_devs(spa, nvroot, crtxg, mode,
3288             &spa->spa_spares, ZPOOL_CONFIG_SPARES, SPA_VERSION_SPARES,
3289             VDEV_LABEL_SPARE)) != 0) {
3290                 return (error);
3291         }
3292 
3293         return (spa_validate_aux_devs(spa, nvroot, crtxg, mode,
3294             &spa->spa_l2cache, ZPOOL_CONFIG_L2CACHE, SPA_VERSION_L2CACHE,
3295             VDEV_LABEL_L2CACHE));
3296 }
3297 
3298 static void
3299 spa_set_aux_vdevs(spa_aux_vdev_t *sav, nvlist_t **devs, int ndevs,
3300     const char *config)
3301 {
3302         int i;
3303 
3304         if (sav->sav_config != NULL) {
3305                 nvlist_t **olddevs;
3306                 uint_t oldndevs;
3307                 nvlist_t **newdevs;
3308 
3309                 /*
3310                  * Generate new dev list by concatentating with the
3311                  * current dev list.
3312                  */
3313                 VERIFY(nvlist_lookup_nvlist_array(sav->sav_config, config,
3314                     &olddevs, &oldndevs) == 0);
3315 
3316                 newdevs = kmem_alloc(sizeof (void *) *
3317                     (ndevs + oldndevs), KM_SLEEP);
3318                 for (i = 0; i < oldndevs; i++)
3319                         VERIFY(nvlist_dup(olddevs[i], &newdevs[i],
3320                             KM_SLEEP) == 0);
3321                 for (i = 0; i < ndevs; i++)
3322                         VERIFY(nvlist_dup(devs[i], &newdevs[i + oldndevs],
3323                             KM_SLEEP) == 0);
3324 
3325                 VERIFY(nvlist_remove(sav->sav_config, config,
3326                     DATA_TYPE_NVLIST_ARRAY) == 0);
3327 
3328                 VERIFY(nvlist_add_nvlist_array(sav->sav_config,
3329                     config, newdevs, ndevs + oldndevs) == 0);
3330                 for (i = 0; i < oldndevs + ndevs; i++)
3331                         nvlist_free(newdevs[i]);
3332                 kmem_free(newdevs, (oldndevs + ndevs) * sizeof (void *));
3333         } else {
3334                 /*
3335                  * Generate a new dev list.
3336                  */
3337                 VERIFY(nvlist_alloc(&sav->sav_config, NV_UNIQUE_NAME,
3338                     KM_SLEEP) == 0);
3339                 VERIFY(nvlist_add_nvlist_array(sav->sav_config, config,
3340                     devs, ndevs) == 0);
3341         }
3342 }
3343 
3344 /*
3345  * Stop and drop level 2 ARC devices
3346  */
3347 void
3348 spa_l2cache_drop(spa_t *spa)
3349 {
3350         vdev_t *vd;
3351         int i;
3352         spa_aux_vdev_t *sav = &spa->spa_l2cache;
3353 
3354         for (i = 0; i < sav->sav_count; i++) {
3355                 uint64_t pool;
3356 
3357                 vd = sav->sav_vdevs[i];
3358                 ASSERT(vd != NULL);
3359 
3360                 if (spa_l2cache_exists(vd->vdev_guid, &pool) &&
3361                     pool != 0ULL && l2arc_vdev_present(vd))
3362                         l2arc_remove_vdev(vd);
3363         }
3364 }
3365 
3366 /*
3367  * Pool Creation
3368  */
3369 int
3370 spa_create(const char *pool, nvlist_t *nvroot, nvlist_t *props,
3371     nvlist_t *zplprops)
3372 {
3373         spa_t *spa;
3374         char *altroot = NULL;
3375         vdev_t *rvd;
3376         dsl_pool_t *dp;
3377         dmu_tx_t *tx;
3378         int error = 0;
3379         uint64_t txg = TXG_INITIAL;
3380         nvlist_t **spares, **l2cache;
3381         uint_t nspares, nl2cache;
3382         uint64_t version, obj;
3383         boolean_t has_features;
3384 
3385         /*
3386          * If this pool already exists, return failure.
3387          */
3388         mutex_enter(&spa_namespace_lock);
3389         if (spa_lookup(pool) != NULL) {
3390                 mutex_exit(&spa_namespace_lock);
3391                 return (SET_ERROR(EEXIST));
3392         }
3393 
3394         /*
3395          * Allocate a new spa_t structure.
3396          */
3397         (void) nvlist_lookup_string(props,
3398             zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
3399         spa = spa_add(pool, NULL, altroot);
3400         spa_activate(spa, spa_mode_global);
3401 
3402         if (props && (error = spa_prop_validate(spa, props))) {
3403                 spa_deactivate(spa);
3404                 spa_remove(spa);
3405                 mutex_exit(&spa_namespace_lock);
3406                 return (error);
3407         }
3408 
3409         has_features = B_FALSE;
3410         for (nvpair_t *elem = nvlist_next_nvpair(props, NULL);
3411             elem != NULL; elem = nvlist_next_nvpair(props, elem)) {
3412                 if (zpool_prop_feature(nvpair_name(elem)))
3413                         has_features = B_TRUE;
3414         }
3415 
3416         if (has_features || nvlist_lookup_uint64(props,
3417             zpool_prop_to_name(ZPOOL_PROP_VERSION), &version) != 0) {
3418                 version = SPA_VERSION;
3419         }
3420         ASSERT(SPA_VERSION_IS_SUPPORTED(version));
3421 
3422         spa->spa_first_txg = txg;
3423         spa->spa_uberblock.ub_txg = txg - 1;
3424         spa->spa_uberblock.ub_version = version;
3425         spa->spa_ubsync = spa->spa_uberblock;
3426 
3427         /*
3428          * Create "The Godfather" zio to hold all async IOs
3429          */
3430         spa->spa_async_zio_root = zio_root(spa, NULL, NULL,
3431             ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_GODFATHER);
3432 
3433         /*
3434          * Create the root vdev.
3435          */
3436         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3437 
3438         error = spa_config_parse(spa, &rvd, nvroot, NULL, 0, VDEV_ALLOC_ADD);
3439 
3440         ASSERT(error != 0 || rvd != NULL);
3441         ASSERT(error != 0 || spa->spa_root_vdev == rvd);
3442 
3443         if (error == 0 && !zfs_allocatable_devs(nvroot))
3444                 error = SET_ERROR(EINVAL);
3445 
3446         if (error == 0 &&
3447             (error = vdev_create(rvd, txg, B_FALSE)) == 0 &&
3448             (error = spa_validate_aux(spa, nvroot, txg,
3449             VDEV_ALLOC_ADD)) == 0) {
3450                 for (int c = 0; c < rvd->vdev_children; c++) {
3451                         vdev_metaslab_set_size(rvd->vdev_child[c]);
3452                         vdev_expand(rvd->vdev_child[c], txg);
3453                 }
3454         }
3455 
3456         spa_config_exit(spa, SCL_ALL, FTAG);
3457 
3458         if (error != 0) {
3459                 spa_unload(spa);
3460                 spa_deactivate(spa);
3461                 spa_remove(spa);
3462                 mutex_exit(&spa_namespace_lock);
3463                 return (error);
3464         }
3465 
3466         /*
3467          * Get the list of spares, if specified.
3468          */
3469         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
3470             &spares, &nspares) == 0) {
3471                 VERIFY(nvlist_alloc(&spa->spa_spares.sav_config, NV_UNIQUE_NAME,
3472                     KM_SLEEP) == 0);
3473                 VERIFY(nvlist_add_nvlist_array(spa->spa_spares.sav_config,
3474                     ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
3475                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3476                 spa_load_spares(spa);
3477                 spa_config_exit(spa, SCL_ALL, FTAG);
3478                 spa->spa_spares.sav_sync = B_TRUE;
3479         }
3480 
3481         /*
3482          * Get the list of level 2 cache devices, if specified.
3483          */
3484         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
3485             &l2cache, &nl2cache) == 0) {
3486                 VERIFY(nvlist_alloc(&spa->spa_l2cache.sav_config,
3487                     NV_UNIQUE_NAME, KM_SLEEP) == 0);
3488                 VERIFY(nvlist_add_nvlist_array(spa->spa_l2cache.sav_config,
3489                     ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
3490                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3491                 spa_load_l2cache(spa);
3492                 spa_config_exit(spa, SCL_ALL, FTAG);
3493                 spa->spa_l2cache.sav_sync = B_TRUE;
3494         }
3495 
3496         spa->spa_is_initializing = B_TRUE;
3497         spa->spa_dsl_pool = dp = dsl_pool_create(spa, zplprops, txg);
3498         spa->spa_meta_objset = dp->dp_meta_objset;
3499         spa->spa_is_initializing = B_FALSE;
3500 
3501         /*
3502          * Create DDTs (dedup tables).
3503          */
3504         ddt_create(spa);
3505 
3506         spa_update_dspace(spa);
3507 
3508         tx = dmu_tx_create_assigned(dp, txg);
3509 
3510         /*
3511          * Create the pool config object.
3512          */
3513         spa->spa_config_object = dmu_object_alloc(spa->spa_meta_objset,
3514             DMU_OT_PACKED_NVLIST, SPA_CONFIG_BLOCKSIZE,
3515             DMU_OT_PACKED_NVLIST_SIZE, sizeof (uint64_t), tx);
3516 
3517         if (zap_add(spa->spa_meta_objset,
3518             DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_CONFIG,
3519             sizeof (uint64_t), 1, &spa->spa_config_object, tx) != 0) {
3520                 cmn_err(CE_PANIC, "failed to add pool config");
3521         }
3522 
3523         if (spa_version(spa) >= SPA_VERSION_FEATURES)
3524                 spa_feature_create_zap_objects(spa, tx);
3525 
3526         if (zap_add(spa->spa_meta_objset,
3527             DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_CREATION_VERSION,
3528             sizeof (uint64_t), 1, &version, tx) != 0) {
3529                 cmn_err(CE_PANIC, "failed to add pool version");
3530         }
3531 
3532         /* Newly created pools with the right version are always deflated. */
3533         if (version >= SPA_VERSION_RAIDZ_DEFLATE) {
3534                 spa->spa_deflate = TRUE;
3535                 if (zap_add(spa->spa_meta_objset,
3536                     DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_DEFLATE,
3537                     sizeof (uint64_t), 1, &spa->spa_deflate, tx) != 0) {
3538                         cmn_err(CE_PANIC, "failed to add deflate");
3539                 }
3540         }
3541 
3542         /*
3543          * Create the deferred-free bpobj.  Turn off compression
3544          * because sync-to-convergence takes longer if the blocksize
3545          * keeps changing.
3546          */
3547         obj = bpobj_alloc(spa->spa_meta_objset, 1 << 14, tx);
3548         dmu_object_set_compress(spa->spa_meta_objset, obj,
3549             ZIO_COMPRESS_OFF, tx);
3550         if (zap_add(spa->spa_meta_objset,
3551             DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_SYNC_BPOBJ,
3552             sizeof (uint64_t), 1, &obj, tx) != 0) {
3553                 cmn_err(CE_PANIC, "failed to add bpobj");
3554         }
3555         VERIFY3U(0, ==, bpobj_open(&spa->spa_deferred_bpobj,
3556             spa->spa_meta_objset, obj));
3557 
3558         /*
3559          * Create the pool's history object.
3560          */
3561         if (version >= SPA_VERSION_ZPOOL_HISTORY)
3562                 spa_history_create_obj(spa, tx);
3563 
3564         /*
3565          * Set pool properties.
3566          */
3567         spa->spa_bootfs = zpool_prop_default_numeric(ZPOOL_PROP_BOOTFS);
3568         spa->spa_delegation = zpool_prop_default_numeric(ZPOOL_PROP_DELEGATION);
3569         spa->spa_failmode = zpool_prop_default_numeric(ZPOOL_PROP_FAILUREMODE);
3570         spa->spa_autoexpand = zpool_prop_default_numeric(ZPOOL_PROP_AUTOEXPAND);
3571 
3572         if (props != NULL) {
3573                 spa_configfile_set(spa, props, B_FALSE);
3574                 spa_sync_props(props, tx);
3575         }
3576 
3577         dmu_tx_commit(tx);
3578 
3579         spa->spa_sync_on = B_TRUE;
3580         txg_sync_start(spa->spa_dsl_pool);
3581 
3582         /*
3583          * We explicitly wait for the first transaction to complete so that our
3584          * bean counters are appropriately updated.
3585          */
3586         txg_wait_synced(spa->spa_dsl_pool, txg);
3587 
3588         spa_config_sync(spa, B_FALSE, B_TRUE);
3589 
3590         spa_history_log_version(spa, "create");
3591 
3592         spa->spa_minref = refcount_count(&spa->spa_refcount);
3593 
3594         mutex_exit(&spa_namespace_lock);
3595 
3596         return (0);
3597 }
3598 
3599 #ifdef _KERNEL
3600 /*
3601  * Get the root pool information from the root disk, then import the root pool
3602  * during the system boot up time.
3603  */
3604 extern int vdev_disk_read_rootlabel(char *, char *, nvlist_t **);
3605 
3606 static nvlist_t *
3607 spa_generate_rootconf(char *devpath, char *devid, uint64_t *guid)
3608 {
3609         nvlist_t *config;
3610         nvlist_t *nvtop, *nvroot;
3611         uint64_t pgid;
3612 
3613         if (vdev_disk_read_rootlabel(devpath, devid, &config) != 0)
3614                 return (NULL);
3615 
3616         /*
3617          * Add this top-level vdev to the child array.
3618          */
3619         VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
3620             &nvtop) == 0);
3621         VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
3622             &pgid) == 0);
3623         VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID, guid) == 0);
3624 
3625         /*
3626          * Put this pool's top-level vdevs into a root vdev.
3627          */
3628         VERIFY(nvlist_alloc(&nvroot, NV_UNIQUE_NAME, KM_SLEEP) == 0);
3629         VERIFY(nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
3630             VDEV_TYPE_ROOT) == 0);
3631         VERIFY(nvlist_add_uint64(nvroot, ZPOOL_CONFIG_ID, 0ULL) == 0);
3632         VERIFY(nvlist_add_uint64(nvroot, ZPOOL_CONFIG_GUID, pgid) == 0);
3633         VERIFY(nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
3634             &nvtop, 1) == 0);
3635 
3636         /*
3637          * Replace the existing vdev_tree with the new root vdev in
3638          * this pool's configuration (remove the old, add the new).
3639          */
3640         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0);
3641         nvlist_free(nvroot);
3642         return (config);
3643 }
3644 
3645 /*
3646  * Walk the vdev tree and see if we can find a device with "better"
3647  * configuration. A configuration is "better" if the label on that
3648  * device has a more recent txg.
3649  */
3650 static void
3651 spa_alt_rootvdev(vdev_t *vd, vdev_t **avd, uint64_t *txg)
3652 {
3653         for (int c = 0; c < vd->vdev_children; c++)
3654                 spa_alt_rootvdev(vd->vdev_child[c], avd, txg);
3655 
3656         if (vd->vdev_ops->vdev_op_leaf) {
3657                 nvlist_t *label;
3658                 uint64_t label_txg;
3659 
3660                 if (vdev_disk_read_rootlabel(vd->vdev_physpath, vd->vdev_devid,
3661                     &label) != 0)
3662                         return;
3663 
3664                 VERIFY(nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG,
3665                     &label_txg) == 0);
3666 
3667                 /*
3668                  * Do we have a better boot device?
3669                  */
3670                 if (label_txg > *txg) {
3671                         *txg = label_txg;
3672                         *avd = vd;
3673                 }
3674                 nvlist_free(label);
3675         }
3676 }
3677 
3678 /*
3679  * Import a root pool.
3680  *
3681  * For x86. devpath_list will consist of devid and/or physpath name of
3682  * the vdev (e.g. "id1,sd@SSEAGATE..." or "/pci@1f,0/ide@d/disk@0,0:a").
3683  * The GRUB "findroot" command will return the vdev we should boot.
3684  *
3685  * For Sparc, devpath_list consists the physpath name of the booting device
3686  * no matter the rootpool is a single device pool or a mirrored pool.
3687  * e.g.
3688  *      "/pci@1f,0/ide@d/disk@0,0:a"
3689  */
3690 int
3691 spa_import_rootpool(char *devpath, char *devid)
3692 {
3693         spa_t *spa;
3694         vdev_t *rvd, *bvd, *avd = NULL;
3695         nvlist_t *config, *nvtop;
3696         uint64_t guid, txg;
3697         char *pname;
3698         int error;
3699 
3700         /*
3701          * Read the label from the boot device and generate a configuration.
3702          */
3703         config = spa_generate_rootconf(devpath, devid, &guid);
3704 #if defined(_OBP) && defined(_KERNEL)
3705         if (config == NULL) {
3706                 if (strstr(devpath, "/iscsi/ssd") != NULL) {
3707                         /* iscsi boot */
3708                         get_iscsi_bootpath_phy(devpath);
3709                         config = spa_generate_rootconf(devpath, devid, &guid);
3710                 }
3711         }
3712 #endif
3713         if (config == NULL) {
3714                 cmn_err(CE_NOTE, "Cannot read the pool label from '%s'",
3715                     devpath);
3716                 return (SET_ERROR(EIO));
3717         }
3718 
3719         VERIFY(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
3720             &pname) == 0);
3721         VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG, &txg) == 0);
3722 
3723         mutex_enter(&spa_namespace_lock);
3724         if ((spa = spa_lookup(pname)) != NULL) {
3725                 /*
3726                  * Remove the existing root pool from the namespace so that we
3727                  * can replace it with the correct config we just read in.
3728                  */
3729                 spa_remove(spa);
3730         }
3731 
3732         spa = spa_add(pname, config, NULL);
3733         spa->spa_is_root = B_TRUE;
3734         spa->spa_import_flags = ZFS_IMPORT_VERBATIM;
3735 
3736         /*
3737          * Build up a vdev tree based on the boot device's label config.
3738          */
3739         VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
3740             &nvtop) == 0);
3741         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3742         error = spa_config_parse(spa, &rvd, nvtop, NULL, 0,
3743             VDEV_ALLOC_ROOTPOOL);
3744         spa_config_exit(spa, SCL_ALL, FTAG);
3745         if (error) {
3746                 mutex_exit(&spa_namespace_lock);
3747                 nvlist_free(config);
3748                 cmn_err(CE_NOTE, "Can not parse the config for pool '%s'",
3749                     pname);
3750                 return (error);
3751         }
3752 
3753         /*
3754          * Get the boot vdev.
3755          */
3756         if ((bvd = vdev_lookup_by_guid(rvd, guid)) == NULL) {
3757                 cmn_err(CE_NOTE, "Can not find the boot vdev for guid %llu",
3758                     (u_longlong_t)guid);
3759                 error = SET_ERROR(ENOENT);
3760                 goto out;
3761         }
3762 
3763         /*
3764          * Determine if there is a better boot device.
3765          */
3766         avd = bvd;
3767         spa_alt_rootvdev(rvd, &avd, &txg);
3768         if (avd != bvd) {
3769                 cmn_err(CE_NOTE, "The boot device is 'degraded'. Please "
3770                     "try booting from '%s'", avd->vdev_path);
3771                 error = SET_ERROR(EINVAL);
3772                 goto out;
3773         }
3774 
3775         /*
3776          * If the boot device is part of a spare vdev then ensure that
3777          * we're booting off the active spare.
3778          */
3779         if (bvd->vdev_parent->vdev_ops == &vdev_spare_ops &&
3780             !bvd->vdev_isspare) {
3781                 cmn_err(CE_NOTE, "The boot device is currently spared. Please "
3782                     "try booting from '%s'",
3783                     bvd->vdev_parent->
3784                     vdev_child[bvd->vdev_parent->vdev_children - 1]->vdev_path);
3785                 error = SET_ERROR(EINVAL);
3786                 goto out;
3787         }
3788 
3789         error = 0;
3790 out:
3791         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3792         vdev_free(rvd);
3793         spa_config_exit(spa, SCL_ALL, FTAG);
3794         mutex_exit(&spa_namespace_lock);
3795 
3796         nvlist_free(config);
3797         return (error);
3798 }
3799 
3800 #endif
3801 
3802 /*
3803  * Import a non-root pool into the system.
3804  */
3805 int
3806 spa_import(const char *pool, nvlist_t *config, nvlist_t *props, uint64_t flags)
3807 {
3808         spa_t *spa;
3809         char *altroot = NULL;
3810         spa_load_state_t state = SPA_LOAD_IMPORT;
3811         zpool_rewind_policy_t policy;
3812         uint64_t mode = spa_mode_global;
3813         uint64_t readonly = B_FALSE;
3814         int error;
3815         nvlist_t *nvroot;
3816         nvlist_t **spares, **l2cache;
3817         uint_t nspares, nl2cache;
3818 
3819         /*
3820          * If a pool with this name exists, return failure.
3821          */
3822         mutex_enter(&spa_namespace_lock);
3823         if (spa_lookup(pool) != NULL) {
3824                 mutex_exit(&spa_namespace_lock);
3825                 return (SET_ERROR(EEXIST));
3826         }
3827 
3828         /*
3829          * Create and initialize the spa structure.
3830          */
3831         (void) nvlist_lookup_string(props,
3832             zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
3833         (void) nvlist_lookup_uint64(props,
3834             zpool_prop_to_name(ZPOOL_PROP_READONLY), &readonly);
3835         if (readonly)
3836                 mode = FREAD;
3837         spa = spa_add(pool, config, altroot);
3838         spa->spa_import_flags = flags;
3839 
3840         /*
3841          * Verbatim import - Take a pool and insert it into the namespace
3842          * as if it had been loaded at boot.
3843          */
3844         if (spa->spa_import_flags & ZFS_IMPORT_VERBATIM) {
3845                 if (props != NULL)
3846                         spa_configfile_set(spa, props, B_FALSE);
3847 
3848                 spa_config_sync(spa, B_FALSE, B_TRUE);
3849 
3850                 mutex_exit(&spa_namespace_lock);
3851                 return (0);
3852         }
3853 
3854         spa_activate(spa, mode);
3855 
3856         /*
3857          * Don't start async tasks until we know everything is healthy.
3858          */
3859         spa_async_suspend(spa);
3860 
3861         zpool_get_rewind_policy(config, &policy);
3862         if (policy.zrp_request & ZPOOL_DO_REWIND)
3863                 state = SPA_LOAD_RECOVER;
3864 
3865         /*
3866          * Pass off the heavy lifting to spa_load().  Pass TRUE for mosconfig
3867          * because the user-supplied config is actually the one to trust when
3868          * doing an import.
3869          */
3870         if (state != SPA_LOAD_RECOVER)
3871                 spa->spa_last_ubsync_txg = spa->spa_load_txg = 0;
3872 
3873         error = spa_load_best(spa, state, B_TRUE, policy.zrp_txg,
3874             policy.zrp_request);
3875 
3876         /*
3877          * Propagate anything learned while loading the pool and pass it
3878          * back to caller (i.e. rewind info, missing devices, etc).
3879          */
3880         VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_LOAD_INFO,
3881             spa->spa_load_info) == 0);
3882 
3883         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3884         /*
3885          * Toss any existing sparelist, as it doesn't have any validity
3886          * anymore, and conflicts with spa_has_spare().
3887          */
3888         if (spa->spa_spares.sav_config) {
3889                 nvlist_free(spa->spa_spares.sav_config);
3890                 spa->spa_spares.sav_config = NULL;
3891                 spa_load_spares(spa);
3892         }
3893         if (spa->spa_l2cache.sav_config) {
3894                 nvlist_free(spa->spa_l2cache.sav_config);
3895                 spa->spa_l2cache.sav_config = NULL;
3896                 spa_load_l2cache(spa);
3897         }
3898 
3899         VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
3900             &nvroot) == 0);
3901         if (error == 0)
3902                 error = spa_validate_aux(spa, nvroot, -1ULL,
3903                     VDEV_ALLOC_SPARE);
3904         if (error == 0)
3905                 error = spa_validate_aux(spa, nvroot, -1ULL,
3906                     VDEV_ALLOC_L2CACHE);
3907         spa_config_exit(spa, SCL_ALL, FTAG);
3908 
3909         if (props != NULL)
3910                 spa_configfile_set(spa, props, B_FALSE);
3911 
3912         if (error != 0 || (props && spa_writeable(spa) &&
3913             (error = spa_prop_set(spa, props)))) {
3914                 spa_unload(spa);
3915                 spa_deactivate(spa);
3916                 spa_remove(spa);
3917                 mutex_exit(&spa_namespace_lock);
3918                 return (error);
3919         }
3920 
3921         spa_async_resume(spa);
3922 
3923         /*
3924          * Override any spares and level 2 cache devices as specified by
3925          * the user, as these may have correct device names/devids, etc.
3926          */
3927         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
3928             &spares, &nspares) == 0) {
3929                 if (spa->spa_spares.sav_config)
3930                         VERIFY(nvlist_remove(spa->spa_spares.sav_config,
3931                             ZPOOL_CONFIG_SPARES, DATA_TYPE_NVLIST_ARRAY) == 0);
3932                 else
3933                         VERIFY(nvlist_alloc(&spa->spa_spares.sav_config,
3934                             NV_UNIQUE_NAME, KM_SLEEP) == 0);
3935                 VERIFY(nvlist_add_nvlist_array(spa->spa_spares.sav_config,
3936                     ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
3937                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3938                 spa_load_spares(spa);
3939                 spa_config_exit(spa, SCL_ALL, FTAG);
3940                 spa->spa_spares.sav_sync = B_TRUE;
3941         }
3942         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
3943             &l2cache, &nl2cache) == 0) {
3944                 if (spa->spa_l2cache.sav_config)
3945                         VERIFY(nvlist_remove(spa->spa_l2cache.sav_config,
3946                             ZPOOL_CONFIG_L2CACHE, DATA_TYPE_NVLIST_ARRAY) == 0);
3947                 else
3948                         VERIFY(nvlist_alloc(&spa->spa_l2cache.sav_config,
3949                             NV_UNIQUE_NAME, KM_SLEEP) == 0);
3950                 VERIFY(nvlist_add_nvlist_array(spa->spa_l2cache.sav_config,
3951                     ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
3952                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3953                 spa_load_l2cache(spa);
3954                 spa_config_exit(spa, SCL_ALL, FTAG);
3955                 spa->spa_l2cache.sav_sync = B_TRUE;
3956         }
3957 
3958         /*
3959          * Check for any removed devices.
3960          */
3961         if (spa->spa_autoreplace) {
3962                 spa_aux_check_removed(&spa->spa_spares);
3963                 spa_aux_check_removed(&spa->spa_l2cache);
3964         }
3965 
3966         if (spa_writeable(spa)) {
3967                 /*
3968                  * Update the config cache to include the newly-imported pool.
3969                  */
3970                 spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
3971         }
3972 
3973         /*
3974          * It's possible that the pool was expanded while it was exported.
3975          * We kick off an async task to handle this for us.
3976          */
3977         spa_async_request(spa, SPA_ASYNC_AUTOEXPAND);
3978 
3979         mutex_exit(&spa_namespace_lock);
3980         spa_history_log_version(spa, "import");
3981 
3982         return (0);
3983 }
3984 
3985 nvlist_t *
3986 spa_tryimport(nvlist_t *tryconfig)
3987 {
3988         nvlist_t *config = NULL;
3989         char *poolname;
3990         spa_t *spa;
3991         uint64_t state;
3992         int error;
3993 
3994         if (nvlist_lookup_string(tryconfig, ZPOOL_CONFIG_POOL_NAME, &poolname))
3995                 return (NULL);
3996 
3997         if (nvlist_lookup_uint64(tryconfig, ZPOOL_CONFIG_POOL_STATE, &state))
3998                 return (NULL);
3999 
4000         /*
4001          * Create and initialize the spa structure.
4002          */
4003         mutex_enter(&spa_namespace_lock);
4004         spa = spa_add(TRYIMPORT_NAME, tryconfig, NULL);
4005         spa_activate(spa, FREAD);
4006 
4007         /*
4008          * Pass off the heavy lifting to spa_load().
4009          * Pass TRUE for mosconfig because the user-supplied config
4010          * is actually the one to trust when doing an import.
4011          */
4012         error = spa_load(spa, SPA_LOAD_TRYIMPORT, SPA_IMPORT_EXISTING, B_TRUE);
4013 
4014         /*
4015          * If 'tryconfig' was at least parsable, return the current config.
4016          */
4017         if (spa->spa_root_vdev != NULL) {
4018                 config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
4019                 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME,
4020                     poolname) == 0);
4021                 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
4022                     state) == 0);
4023                 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TIMESTAMP,
4024                     spa->spa_uberblock.ub_timestamp) == 0);
4025                 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_LOAD_INFO,
4026                     spa->spa_load_info) == 0);
4027 
4028                 /*
4029                  * If the bootfs property exists on this pool then we
4030                  * copy it out so that external consumers can tell which
4031                  * pools are bootable.
4032                  */
4033                 if ((!error || error == EEXIST) && spa->spa_bootfs) {
4034                         char *tmpname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
4035 
4036                         /*
4037                          * We have to play games with the name since the
4038                          * pool was opened as TRYIMPORT_NAME.
4039                          */
4040                         if (dsl_dsobj_to_dsname(spa_name(spa),
4041                             spa->spa_bootfs, tmpname) == 0) {
4042                                 char *cp;
4043                                 char *dsname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
4044 
4045                                 cp = strchr(tmpname, '/');
4046                                 if (cp == NULL) {
4047                                         (void) strlcpy(dsname, tmpname,
4048                                             MAXPATHLEN);
4049                                 } else {
4050                                         (void) snprintf(dsname, MAXPATHLEN,
4051                                             "%s/%s", poolname, ++cp);
4052                                 }
4053                                 VERIFY(nvlist_add_string(config,
4054                                     ZPOOL_CONFIG_BOOTFS, dsname) == 0);
4055                                 kmem_free(dsname, MAXPATHLEN);
4056                         }
4057                         kmem_free(tmpname, MAXPATHLEN);
4058                 }
4059 
4060                 /*
4061                  * Add the list of hot spares and level 2 cache devices.
4062                  */
4063                 spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
4064                 spa_add_spares(spa, config);
4065                 spa_add_l2cache(spa, config);
4066                 spa_config_exit(spa, SCL_CONFIG, FTAG);
4067         }
4068 
4069         spa_unload(spa);
4070         spa_deactivate(spa);
4071         spa_remove(spa);
4072         mutex_exit(&spa_namespace_lock);
4073 
4074         return (config);
4075 }
4076 
4077 /*
4078  * Pool export/destroy
4079  *
4080  * The act of destroying or exporting a pool is very simple.  We make sure there
4081  * is no more pending I/O and any references to the pool are gone.  Then, we
4082  * update the pool state and sync all the labels to disk, removing the
4083  * configuration from the cache afterwards. If the 'hardforce' flag is set, then
4084  * we don't sync the labels or remove the configuration cache.
4085  */
4086 static int
4087 spa_export_common(char *pool, int new_state, nvlist_t **oldconfig,
4088     boolean_t force, boolean_t hardforce)
4089 {
4090         spa_t *spa;
4091 
4092         if (oldconfig)
4093                 *oldconfig = NULL;
4094 
4095         if (!(spa_mode_global & FWRITE))
4096                 return (SET_ERROR(EROFS));
4097 
4098         mutex_enter(&spa_namespace_lock);
4099         if ((spa = spa_lookup(pool)) == NULL) {
4100                 mutex_exit(&spa_namespace_lock);
4101                 return (SET_ERROR(ENOENT));
4102         }
4103 
4104         /*
4105          * Put a hold on the pool, drop the namespace lock, stop async tasks,
4106          * reacquire the namespace lock, and see if we can export.
4107          */
4108         spa_open_ref(spa, FTAG);
4109         mutex_exit(&spa_namespace_lock);
4110         spa_async_suspend(spa);
4111         mutex_enter(&spa_namespace_lock);
4112         spa_close(spa, FTAG);
4113 
4114         /*
4115          * The pool will be in core if it's openable,
4116          * in which case we can modify its state.
4117          */
4118         if (spa->spa_state != POOL_STATE_UNINITIALIZED && spa->spa_sync_on) {
4119                 /*
4120                  * Objsets may be open only because they're dirty, so we
4121                  * have to force it to sync before checking spa_refcnt.
4122                  */
4123                 txg_wait_synced(spa->spa_dsl_pool, 0);
4124 
4125                 /*
4126                  * A pool cannot be exported or destroyed if there are active
4127                  * references.  If we are resetting a pool, allow references by
4128                  * fault injection handlers.
4129                  */
4130                 if (!spa_refcount_zero(spa) ||
4131                     (spa->spa_inject_ref != 0 &&
4132                     new_state != POOL_STATE_UNINITIALIZED)) {
4133                         spa_async_resume(spa);
4134                         mutex_exit(&spa_namespace_lock);
4135                         return (SET_ERROR(EBUSY));
4136                 }
4137 
4138                 /*
4139                  * A pool cannot be exported if it has an active shared spare.
4140                  * This is to prevent other pools stealing the active spare
4141                  * from an exported pool. At user's own will, such pool can
4142                  * be forcedly exported.
4143                  */
4144                 if (!force && new_state == POOL_STATE_EXPORTED &&
4145                     spa_has_active_shared_spare(spa)) {
4146                         spa_async_resume(spa);
4147                         mutex_exit(&spa_namespace_lock);
4148                         return (SET_ERROR(EXDEV));
4149                 }
4150 
4151                 /*
4152                  * We want this to be reflected on every label,
4153                  * so mark them all dirty.  spa_unload() will do the
4154                  * final sync that pushes these changes out.
4155                  */
4156                 if (new_state != POOL_STATE_UNINITIALIZED && !hardforce) {
4157                         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
4158                         spa->spa_state = new_state;
4159                         spa->spa_final_txg = spa_last_synced_txg(spa) +
4160                             TXG_DEFER_SIZE + 1;
4161                         vdev_config_dirty(spa->spa_root_vdev);
4162                         spa_config_exit(spa, SCL_ALL, FTAG);
4163                 }
4164         }
4165 
4166         spa_event_notify(spa, NULL, ESC_ZFS_POOL_DESTROY);
4167 
4168         if (spa->spa_state != POOL_STATE_UNINITIALIZED) {
4169                 spa_unload(spa);
4170                 spa_deactivate(spa);
4171         }
4172 
4173         if (oldconfig && spa->spa_config)
4174                 VERIFY(nvlist_dup(spa->spa_config, oldconfig, 0) == 0);
4175 
4176         if (new_state != POOL_STATE_UNINITIALIZED) {
4177                 if (!hardforce)
4178                         spa_config_sync(spa, B_TRUE, B_TRUE);
4179                 spa_remove(spa);
4180         }
4181         mutex_exit(&spa_namespace_lock);
4182 
4183         return (0);
4184 }
4185 
4186 /*
4187  * Destroy a storage pool.
4188  */
4189 int
4190 spa_destroy(char *pool)
4191 {
4192         return (spa_export_common(pool, POOL_STATE_DESTROYED, NULL,
4193             B_FALSE, B_FALSE));
4194 }
4195 
4196 /*
4197  * Export a storage pool.
4198  */
4199 int
4200 spa_export(char *pool, nvlist_t **oldconfig, boolean_t force,
4201     boolean_t hardforce)
4202 {
4203         return (spa_export_common(pool, POOL_STATE_EXPORTED, oldconfig,
4204             force, hardforce));
4205 }
4206 
4207 /*
4208  * Similar to spa_export(), this unloads the spa_t without actually removing it
4209  * from the namespace in any way.
4210  */
4211 int
4212 spa_reset(char *pool)
4213 {
4214         return (spa_export_common(pool, POOL_STATE_UNINITIALIZED, NULL,
4215             B_FALSE, B_FALSE));
4216 }
4217 
4218 /*
4219  * ==========================================================================
4220  * Device manipulation
4221  * ==========================================================================
4222  */
4223 
4224 /*
4225  * Add a device to a storage pool.
4226  */
4227 int
4228 spa_vdev_add(spa_t *spa, nvlist_t *nvroot)
4229 {
4230         uint64_t txg, id;
4231         int error;
4232         vdev_t *rvd = spa->spa_root_vdev;
4233         vdev_t *vd, *tvd;
4234         nvlist_t **spares, **l2cache;
4235         uint_t nspares, nl2cache;
4236 
4237         ASSERT(spa_writeable(spa));
4238 
4239         txg = spa_vdev_enter(spa);
4240 
4241         if ((error = spa_config_parse(spa, &vd, nvroot, NULL, 0,
4242             VDEV_ALLOC_ADD)) != 0)
4243                 return (spa_vdev_exit(spa, NULL, txg, error));
4244 
4245         spa->spa_pending_vdev = vd;  /* spa_vdev_exit() will clear this */
4246 
4247         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES, &spares,
4248             &nspares) != 0)
4249                 nspares = 0;
4250 
4251         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE, &l2cache,
4252             &nl2cache) != 0)
4253                 nl2cache = 0;
4254 
4255         if (vd->vdev_children == 0 && nspares == 0 && nl2cache == 0)
4256                 return (spa_vdev_exit(spa, vd, txg, EINVAL));
4257 
4258         if (vd->vdev_children != 0 &&
4259             (error = vdev_create(vd, txg, B_FALSE)) != 0)
4260                 return (spa_vdev_exit(spa, vd, txg, error));
4261 
4262         /*
4263          * We must validate the spares and l2cache devices after checking the
4264          * children.  Otherwise, vdev_inuse() will blindly overwrite the spare.
4265          */
4266         if ((error = spa_validate_aux(spa, nvroot, txg, VDEV_ALLOC_ADD)) != 0)
4267                 return (spa_vdev_exit(spa, vd, txg, error));
4268 
4269         /*
4270          * Transfer each new top-level vdev from vd to rvd.
4271          */
4272         for (int c = 0; c < vd->vdev_children; c++) {
4273 
4274                 /*
4275                  * Set the vdev id to the first hole, if one exists.
4276                  */
4277                 for (id = 0; id < rvd->vdev_children; id++) {
4278                         if (rvd->vdev_child[id]->vdev_ishole) {
4279                                 vdev_free(rvd->vdev_child[id]);
4280                                 break;
4281                         }
4282                 }
4283                 tvd = vd->vdev_child[c];
4284                 vdev_remove_child(vd, tvd);
4285                 tvd->vdev_id = id;
4286                 vdev_add_child(rvd, tvd);
4287                 vdev_config_dirty(tvd);
4288         }
4289 
4290         if (nspares != 0) {
4291                 spa_set_aux_vdevs(&spa->spa_spares, spares, nspares,
4292                     ZPOOL_CONFIG_SPARES);
4293                 spa_load_spares(spa);
4294                 spa->spa_spares.sav_sync = B_TRUE;
4295         }
4296 
4297         if (nl2cache != 0) {
4298                 spa_set_aux_vdevs(&spa->spa_l2cache, l2cache, nl2cache,
4299                     ZPOOL_CONFIG_L2CACHE);
4300                 spa_load_l2cache(spa);
4301                 spa->spa_l2cache.sav_sync = B_TRUE;
4302         }
4303 
4304         /*
4305          * We have to be careful when adding new vdevs to an existing pool.
4306          * If other threads start allocating from these vdevs before we
4307          * sync the config cache, and we lose power, then upon reboot we may
4308          * fail to open the pool because there are DVAs that the config cache
4309          * can't translate.  Therefore, we first add the vdevs without
4310          * initializing metaslabs; sync the config cache (via spa_vdev_exit());
4311          * and then let spa_config_update() initialize the new metaslabs.
4312          *
4313          * spa_load() checks for added-but-not-initialized vdevs, so that
4314          * if we lose power at any point in this sequence, the remaining
4315          * steps will be completed the next time we load the pool.
4316          */
4317         (void) spa_vdev_exit(spa, vd, txg, 0);
4318 
4319         mutex_enter(&spa_namespace_lock);
4320         spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
4321         mutex_exit(&spa_namespace_lock);
4322 
4323         return (0);
4324 }
4325 
4326 /*
4327  * Attach a device to a mirror.  The arguments are the path to any device
4328  * in the mirror, and the nvroot for the new device.  If the path specifies
4329  * a device that is not mirrored, we automatically insert the mirror vdev.
4330  *
4331  * If 'replacing' is specified, the new device is intended to replace the
4332  * existing device; in this case the two devices are made into their own
4333  * mirror using the 'replacing' vdev, which is functionally identical to
4334  * the mirror vdev (it actually reuses all the same ops) but has a few
4335  * extra rules: you can't attach to it after it's been created, and upon
4336  * completion of resilvering, the first disk (the one being replaced)
4337  * is automatically detached.
4338  */
4339 int
4340 spa_vdev_attach(spa_t *spa, uint64_t guid, nvlist_t *nvroot, int replacing)
4341 {
4342         uint64_t txg, dtl_max_txg;
4343         vdev_t *rvd = spa->spa_root_vdev;
4344         vdev_t *oldvd, *newvd, *newrootvd, *pvd, *tvd;
4345         vdev_ops_t *pvops;
4346         char *oldvdpath, *newvdpath;
4347         int newvd_isspare;
4348         int error;
4349 
4350         ASSERT(spa_writeable(spa));
4351 
4352         txg = spa_vdev_enter(spa);
4353 
4354         oldvd = spa_lookup_by_guid(spa, guid, B_FALSE);
4355 
4356         if (oldvd == NULL)
4357                 return (spa_vdev_exit(spa, NULL, txg, ENODEV));
4358 
4359         if (!oldvd->vdev_ops->vdev_op_leaf)
4360                 return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
4361 
4362         pvd = oldvd->vdev_parent;
4363 
4364         if ((error = spa_config_parse(spa, &newrootvd, nvroot, NULL, 0,
4365             VDEV_ALLOC_ATTACH)) != 0)
4366                 return (spa_vdev_exit(spa, NULL, txg, EINVAL));
4367 
4368         if (newrootvd->vdev_children != 1)
4369                 return (spa_vdev_exit(spa, newrootvd, txg, EINVAL));
4370 
4371         newvd = newrootvd->vdev_child[0];
4372 
4373         if (!newvd->vdev_ops->vdev_op_leaf)
4374                 return (spa_vdev_exit(spa, newrootvd, txg, EINVAL));
4375 
4376         if ((error = vdev_create(newrootvd, txg, replacing)) != 0)
4377                 return (spa_vdev_exit(spa, newrootvd, txg, error));
4378 
4379         /*
4380          * Spares can't replace logs
4381          */
4382         if (oldvd->vdev_top->vdev_islog && newvd->vdev_isspare)
4383                 return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4384 
4385         if (!replacing) {
4386                 /*
4387                  * For attach, the only allowable parent is a mirror or the root
4388                  * vdev.
4389                  */
4390                 if (pvd->vdev_ops != &vdev_mirror_ops &&
4391                     pvd->vdev_ops != &vdev_root_ops)
4392                         return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4393 
4394                 pvops = &vdev_mirror_ops;
4395         } else {
4396                 /*
4397                  * Active hot spares can only be replaced by inactive hot
4398                  * spares.
4399                  */
4400                 if (pvd->vdev_ops == &vdev_spare_ops &&
4401                     oldvd->vdev_isspare &&
4402                     !spa_has_spare(spa, newvd->vdev_guid))
4403                         return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4404 
4405                 /*
4406                  * If the source is a hot spare, and the parent isn't already a
4407                  * spare, then we want to create a new hot spare.  Otherwise, we
4408                  * want to create a replacing vdev.  The user is not allowed to
4409                  * attach to a spared vdev child unless the 'isspare' state is
4410                  * the same (spare replaces spare, non-spare replaces
4411                  * non-spare).
4412                  */
4413                 if (pvd->vdev_ops == &vdev_replacing_ops &&
4414                     spa_version(spa) < SPA_VERSION_MULTI_REPLACE) {
4415                         return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4416                 } else if (pvd->vdev_ops == &vdev_spare_ops &&
4417                     newvd->vdev_isspare != oldvd->vdev_isspare) {
4418                         return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
4419                 }
4420 
4421                 if (newvd->vdev_isspare)
4422                         pvops = &vdev_spare_ops;
4423                 else
4424                         pvops = &vdev_replacing_ops;
4425         }
4426 
4427         /*
4428          * Make sure the new device is big enough.
4429          */
4430         if (newvd->vdev_asize < vdev_get_min_asize(oldvd))
4431                 return (spa_vdev_exit(spa, newrootvd, txg, EOVERFLOW));
4432 
4433         /*
4434          * The new device cannot have a higher alignment requirement
4435          * than the top-level vdev.
4436          */
4437         if (newvd->vdev_ashift > oldvd->vdev_top->vdev_ashift)
4438                 return (spa_vdev_exit(spa, newrootvd, txg, EDOM));
4439 
4440         /*
4441          * If this is an in-place replacement, update oldvd's path and devid
4442          * to make it distinguishable from newvd, and unopenable from now on.
4443          */
4444         if (strcmp(oldvd->vdev_path, newvd->vdev_path) == 0) {
4445                 spa_strfree(oldvd->vdev_path);
4446                 oldvd->vdev_path = kmem_alloc(strlen(newvd->vdev_path) + 5,
4447                     KM_SLEEP);
4448                 (void) sprintf(oldvd->vdev_path, "%s/%s",
4449                     newvd->vdev_path, "old");
4450                 if (oldvd->vdev_devid != NULL) {
4451                         spa_strfree(oldvd->vdev_devid);
4452                         oldvd->vdev_devid = NULL;
4453                 }
4454         }
4455 
4456         /* mark the device being resilvered */
4457         newvd->vdev_resilver_txg = txg;
4458 
4459         /*
4460          * If the parent is not a mirror, or if we're replacing, insert the new
4461          * mirror/replacing/spare vdev above oldvd.
4462          */
4463         if (pvd->vdev_ops != pvops)
4464                 pvd = vdev_add_parent(oldvd, pvops);
4465 
4466         ASSERT(pvd->vdev_top->vdev_parent == rvd);
4467         ASSERT(pvd->vdev_ops == pvops);
4468         ASSERT(oldvd->vdev_parent == pvd);
4469 
4470         /*
4471          * Extract the new device from its root and add it to pvd.
4472          */
4473         vdev_remove_child(newrootvd, newvd);
4474         newvd->vdev_id = pvd->vdev_children;
4475         newvd->vdev_crtxg = oldvd->vdev_crtxg;
4476         vdev_add_child(pvd, newvd);
4477 
4478         tvd = newvd->vdev_top;
4479         ASSERT(pvd->vdev_top == tvd);
4480         ASSERT(tvd->vdev_parent == rvd);
4481 
4482         vdev_config_dirty(tvd);
4483 
4484         /*
4485          * Set newvd's DTL to [TXG_INITIAL, dtl_max_txg) so that we account
4486          * for any dmu_sync-ed blocks.  It will propagate upward when
4487          * spa_vdev_exit() calls vdev_dtl_reassess().
4488          */
4489         dtl_max_txg = txg + TXG_CONCURRENT_STATES;
4490 
4491         vdev_dtl_dirty(newvd, DTL_MISSING, TXG_INITIAL,
4492             dtl_max_txg - TXG_INITIAL);
4493 
4494         if (newvd->vdev_isspare) {
4495                 spa_spare_activate(newvd);
4496                 spa_event_notify(spa, newvd, ESC_ZFS_VDEV_SPARE);
4497         }
4498 
4499         oldvdpath = spa_strdup(oldvd->vdev_path);
4500         newvdpath = spa_strdup(newvd->vdev_path);
4501         newvd_isspare = newvd->vdev_isspare;
4502 
4503         /*
4504          * Mark newvd's DTL dirty in this txg.
4505          */
4506         vdev_dirty(tvd, VDD_DTL, newvd, txg);
4507 
4508         /*
4509          * Schedule the resilver to restart in the future. We do this to
4510          * ensure that dmu_sync-ed blocks have been stitched into the
4511          * respective datasets.
4512          */
4513         dsl_resilver_restart(spa->spa_dsl_pool, dtl_max_txg);
4514 
4515         /*
4516          * Commit the config
4517          */
4518         (void) spa_vdev_exit(spa, newrootvd, dtl_max_txg, 0);
4519 
4520         spa_history_log_internal(spa, "vdev attach", NULL,
4521             "%s vdev=%s %s vdev=%s",
4522             replacing && newvd_isspare ? "spare in" :
4523             replacing ? "replace" : "attach", newvdpath,
4524             replacing ? "for" : "to", oldvdpath);
4525 
4526         spa_strfree(oldvdpath);
4527         spa_strfree(newvdpath);
4528 
4529         if (spa->spa_bootfs)
4530                 spa_event_notify(spa, newvd, ESC_ZFS_BOOTFS_VDEV_ATTACH);
4531 
4532         return (0);
4533 }
4534 
4535 /*
4536  * Detach a device from a mirror or replacing vdev.
4537  *
4538  * If 'replace_done' is specified, only detach if the parent
4539  * is a replacing vdev.
4540  */
4541 int
4542 spa_vdev_detach(spa_t *spa, uint64_t guid, uint64_t pguid, int replace_done)
4543 {
4544         uint64_t txg;
4545         int error;
4546         vdev_t *rvd = spa->spa_root_vdev;
4547         vdev_t *vd, *pvd, *cvd, *tvd;
4548         boolean_t unspare = B_FALSE;
4549         uint64_t unspare_guid = 0;
4550         char *vdpath;
4551 
4552         ASSERT(spa_writeable(spa));
4553 
4554         txg = spa_vdev_enter(spa);
4555 
4556         vd = spa_lookup_by_guid(spa, guid, B_FALSE);
4557 
4558         if (vd == NULL)
4559                 return (spa_vdev_exit(spa, NULL, txg, ENODEV));
4560 
4561         if (!vd->vdev_ops->vdev_op_leaf)
4562                 return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
4563 
4564         pvd = vd->vdev_parent;
4565 
4566         /*
4567          * If the parent/child relationship is not as expected, don't do it.
4568          * Consider M(A,R(B,C)) -- that is, a mirror of A with a replacing
4569          * vdev that's replacing B with C.  The user's intent in replacing
4570          * is to go from M(A,B) to M(A,C).  If the user decides to cancel
4571          * the replace by detaching C, the expected behavior is to end up
4572          * M(A,B).  But suppose that right after deciding to detach C,
4573          * the replacement of B completes.  We would have M(A,C), and then
4574          * ask to detach C, which would leave us with just A -- not what
4575          * the user wanted.  To prevent this, we make sure that the
4576          * parent/child relationship hasn't changed -- in this example,
4577          * that C's parent is still the replacing vdev R.
4578          */
4579         if (pvd->vdev_guid != pguid && pguid != 0)
4580                 return (spa_vdev_exit(spa, NULL, txg, EBUSY));
4581 
4582         /*
4583          * Only 'replacing' or 'spare' vdevs can be replaced.
4584          */
4585         if (replace_done && pvd->vdev_ops != &vdev_replacing_ops &&
4586             pvd->vdev_ops != &vdev_spare_ops)
4587                 return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
4588 
4589         ASSERT(pvd->vdev_ops != &vdev_spare_ops ||
4590             spa_version(spa) >= SPA_VERSION_SPARES);
4591 
4592         /*
4593          * Only mirror, replacing, and spare vdevs support detach.
4594          */
4595         if (pvd->vdev_ops != &vdev_replacing_ops &&
4596             pvd->vdev_ops != &vdev_mirror_ops &&
4597             pvd->vdev_ops != &vdev_spare_ops)
4598                 return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
4599 
4600         /*
4601          * If this device has the only valid copy of some data,
4602          * we cannot safely detach it.
4603          */
4604         if (vdev_dtl_required(vd))
4605                 return (spa_vdev_exit(spa, NULL, txg, EBUSY));
4606 
4607         ASSERT(pvd->vdev_children >= 2);
4608 
4609         /*
4610          * If we are detaching the second disk from a replacing vdev, then
4611          * check to see if we changed the original vdev's path to have "/old"
4612          * at the end in spa_vdev_attach().  If so, undo that change now.
4613          */
4614         if (pvd->vdev_ops == &vdev_replacing_ops && vd->vdev_id > 0 &&
4615             vd->vdev_path != NULL) {
4616                 size_t len = strlen(vd->vdev_path);
4617 
4618                 for (int c = 0; c < pvd->vdev_children; c++) {
4619                         cvd = pvd->vdev_child[c];
4620 
4621                         if (cvd == vd || cvd->vdev_path == NULL)
4622                                 continue;
4623 
4624                         if (strncmp(cvd->vdev_path, vd->vdev_path, len) == 0 &&
4625                             strcmp(cvd->vdev_path + len, "/old") == 0) {
4626                                 spa_strfree(cvd->vdev_path);
4627                                 cvd->vdev_path = spa_strdup(vd->vdev_path);
4628                                 break;
4629                         }
4630                 }
4631         }
4632 
4633         /*
4634          * If we are detaching the original disk from a spare, then it implies
4635          * that the spare should become a real disk, and be removed from the
4636          * active spare list for the pool.
4637          */
4638         if (pvd->vdev_ops == &vdev_spare_ops &&
4639             vd->vdev_id == 0 &&
4640             pvd->vdev_child[pvd->vdev_children - 1]->vdev_isspare)
4641                 unspare = B_TRUE;
4642 
4643         /*
4644          * Erase the disk labels so the disk can be used for other things.
4645          * This must be done after all other error cases are handled,
4646          * but before we disembowel vd (so we can still do I/O to it).
4647          * But if we can't do it, don't treat the error as fatal --
4648          * it may be that the unwritability of the disk is the reason
4649          * it's being detached!
4650          */
4651         error = vdev_label_init(vd, 0, VDEV_LABEL_REMOVE);
4652 
4653         /*
4654          * Remove vd from its parent and compact the parent's children.
4655          */
4656         vdev_remove_child(pvd, vd);
4657         vdev_compact_children(pvd);
4658 
4659         /*
4660          * Remember one of the remaining children so we can get tvd below.
4661          */
4662         cvd = pvd->vdev_child[pvd->vdev_children - 1];
4663 
4664         /*
4665          * If we need to remove the remaining child from the list of hot spares,
4666          * do it now, marking the vdev as no longer a spare in the process.
4667          * We must do this before vdev_remove_parent(), because that can
4668          * change the GUID if it creates a new toplevel GUID.  For a similar
4669          * reason, we must remove the spare now, in the same txg as the detach;
4670          * otherwise someone could attach a new sibling, change the GUID, and
4671          * the subsequent attempt to spa_vdev_remove(unspare_guid) would fail.
4672          */
4673         if (unspare) {
4674                 ASSERT(cvd->vdev_isspare);
4675                 spa_spare_remove(cvd);
4676                 unspare_guid = cvd->vdev_guid;
4677                 (void) spa_vdev_remove(spa, unspare_guid, B_TRUE);
4678                 cvd->vdev_unspare = B_TRUE;
4679         }
4680 
4681         /*
4682          * If the parent mirror/replacing vdev only has one child,
4683          * the parent is no longer needed.  Remove it from the tree.
4684          */
4685         if (pvd->vdev_children == 1) {
4686                 if (pvd->vdev_ops == &vdev_spare_ops)
4687                         cvd->vdev_unspare = B_FALSE;
4688                 vdev_remove_parent(cvd);
4689         }
4690 
4691 
4692         /*
4693          * We don't set tvd until now because the parent we just removed
4694          * may have been the previous top-level vdev.
4695          */
4696         tvd = cvd->vdev_top;
4697         ASSERT(tvd->vdev_parent == rvd);
4698 
4699         /*
4700          * Reevaluate the parent vdev state.
4701          */
4702         vdev_propagate_state(cvd);
4703 
4704         /*
4705          * If the 'autoexpand' property is set on the pool then automatically
4706          * try to expand the size of the pool. For example if the device we
4707          * just detached was smaller than the others, it may be possible to
4708          * add metaslabs (i.e. grow the pool). We need to reopen the vdev
4709          * first so that we can obtain the updated sizes of the leaf vdevs.
4710          */
4711         if (spa->spa_autoexpand) {
4712                 vdev_reopen(tvd);
4713                 vdev_expand(tvd, txg);
4714         }
4715 
4716         vdev_config_dirty(tvd);
4717 
4718         /*
4719          * Mark vd's DTL as dirty in this txg.  vdev_dtl_sync() will see that
4720          * vd->vdev_detached is set and free vd's DTL object in syncing context.
4721          * But first make sure we're not on any *other* txg's DTL list, to
4722          * prevent vd from being accessed after it's freed.
4723          */
4724         vdpath = spa_strdup(vd->vdev_path);
4725         for (int t = 0; t < TXG_SIZE; t++)
4726                 (void) txg_list_remove_this(&tvd->vdev_dtl_list, vd, t);
4727         vd->vdev_detached = B_TRUE;
4728         vdev_dirty(tvd, VDD_DTL, vd, txg);
4729 
4730         spa_event_notify(spa, vd, ESC_ZFS_VDEV_REMOVE);
4731 
4732         /* hang on to the spa before we release the lock */
4733         spa_open_ref(spa, FTAG);
4734 
4735         error = spa_vdev_exit(spa, vd, txg, 0);
4736 
4737         spa_history_log_internal(spa, "detach", NULL,
4738             "vdev=%s", vdpath);
4739         spa_strfree(vdpath);
4740 
4741         /*
4742          * If this was the removal of the original device in a hot spare vdev,
4743          * then we want to go through and remove the device from the hot spare
4744          * list of every other pool.
4745          */
4746         if (unspare) {
4747                 spa_t *altspa = NULL;
4748 
4749                 mutex_enter(&spa_namespace_lock);
4750                 while ((altspa = spa_next(altspa)) != NULL) {
4751                         if (altspa->spa_state != POOL_STATE_ACTIVE ||
4752                             altspa == spa)
4753                                 continue;
4754 
4755                         spa_open_ref(altspa, FTAG);
4756                         mutex_exit(&spa_namespace_lock);
4757                         (void) spa_vdev_remove(altspa, unspare_guid, B_TRUE);
4758                         mutex_enter(&spa_namespace_lock);
4759                         spa_close(altspa, FTAG);
4760                 }
4761                 mutex_exit(&spa_namespace_lock);
4762 
4763                 /* search the rest of the vdevs for spares to remove */
4764                 spa_vdev_resilver_done(spa);
4765         }
4766 
4767         /* all done with the spa; OK to release */
4768         mutex_enter(&spa_namespace_lock);
4769         spa_close(spa, FTAG);
4770         mutex_exit(&spa_namespace_lock);
4771 
4772         return (error);
4773 }
4774 
4775 /*
4776  * Split a set of devices from their mirrors, and create a new pool from them.
4777  */
4778 int
4779 spa_vdev_split_mirror(spa_t *spa, char *newname, nvlist_t *config,
4780     nvlist_t *props, boolean_t exp)
4781 {
4782         int error = 0;
4783         uint64_t txg, *glist;
4784         spa_t *newspa;
4785         uint_t c, children, lastlog;
4786         nvlist_t **child, *nvl, *tmp;
4787         dmu_tx_t *tx;
4788         char *altroot = NULL;
4789         vdev_t *rvd, **vml = NULL;                      /* vdev modify list */
4790         boolean_t activate_slog;
4791 
4792         ASSERT(spa_writeable(spa));
4793 
4794         txg = spa_vdev_enter(spa);
4795 
4796         /* clear the log and flush everything up to now */
4797         activate_slog = spa_passivate_log(spa);
4798         (void) spa_vdev_config_exit(spa, NULL, txg, 0, FTAG);
4799         error = spa_offline_log(spa);
4800         txg = spa_vdev_config_enter(spa);
4801 
4802         if (activate_slog)
4803                 spa_activate_log(spa);
4804 
4805         if (error != 0)
4806                 return (spa_vdev_exit(spa, NULL, txg, error));
4807 
4808         /* check new spa name before going any further */
4809         if (spa_lookup(newname) != NULL)
4810                 return (spa_vdev_exit(spa, NULL, txg, EEXIST));
4811 
4812         /*
4813          * scan through all the children to ensure they're all mirrors
4814          */
4815         if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nvl) != 0 ||
4816             nvlist_lookup_nvlist_array(nvl, ZPOOL_CONFIG_CHILDREN, &child,
4817             &children) != 0)
4818                 return (spa_vdev_exit(spa, NULL, txg, EINVAL));
4819 
4820         /* first, check to ensure we've got the right child count */
4821         rvd = spa->spa_root_vdev;
4822         lastlog = 0;
4823         for (c = 0; c < rvd->vdev_children; c++) {
4824                 vdev_t *vd = rvd->vdev_child[c];
4825 
4826                 /* don't count the holes & logs as children */
4827                 if (vd->vdev_islog || vd->vdev_ishole) {
4828                         if (lastlog == 0)
4829                                 lastlog = c;
4830                         continue;
4831                 }
4832 
4833                 lastlog = 0;
4834         }
4835         if (children != (lastlog != 0 ? lastlog : rvd->vdev_children))
4836                 return (spa_vdev_exit(spa, NULL, txg, EINVAL));
4837 
4838         /* next, ensure no spare or cache devices are part of the split */
4839         if (nvlist_lookup_nvlist(nvl, ZPOOL_CONFIG_SPARES, &tmp) == 0 ||
4840             nvlist_lookup_nvlist(nvl, ZPOOL_CONFIG_L2CACHE, &tmp) == 0)
4841                 return (spa_vdev_exit(spa, NULL, txg, EINVAL));
4842 
4843         vml = kmem_zalloc(children * sizeof (vdev_t *), KM_SLEEP);
4844         glist = kmem_zalloc(children * sizeof (uint64_t), KM_SLEEP);
4845 
4846         /* then, loop over each vdev and validate it */
4847         for (c = 0; c < children; c++) {
4848                 uint64_t is_hole = 0;
4849 
4850                 (void) nvlist_lookup_uint64(child[c], ZPOOL_CONFIG_IS_HOLE,
4851                     &is_hole);
4852 
4853                 if (is_hole != 0) {
4854                         if (spa->spa_root_vdev->vdev_child[c]->vdev_ishole ||
4855                             spa->spa_root_vdev->vdev_child[c]->vdev_islog) {
4856                                 continue;
4857                         } else {
4858                                 error = SET_ERROR(EINVAL);
4859                                 break;
4860                         }
4861                 }
4862 
4863                 /* which disk is going to be split? */
4864                 if (nvlist_lookup_uint64(child[c], ZPOOL_CONFIG_GUID,
4865                     &glist[c]) != 0) {
4866                         error = SET_ERROR(EINVAL);
4867                         break;
4868                 }
4869 
4870                 /* look it up in the spa */
4871                 vml[c] = spa_lookup_by_guid(spa, glist[c], B_FALSE);
4872                 if (vml[c] == NULL) {
4873                         error = SET_ERROR(ENODEV);
4874                         break;
4875                 }
4876 
4877                 /* make sure there's nothing stopping the split */
4878                 if (vml[c]->vdev_parent->vdev_ops != &vdev_mirror_ops ||
4879                     vml[c]->vdev_islog ||
4880                     vml[c]->vdev_ishole ||
4881                     vml[c]->vdev_isspare ||
4882                     vml[c]->vdev_isl2cache ||
4883                     !vdev_writeable(vml[c]) ||
4884                     vml[c]->vdev_children != 0 ||
4885                     vml[c]->vdev_state != VDEV_STATE_HEALTHY ||
4886                     c != spa->spa_root_vdev->vdev_child[c]->vdev_id) {
4887                         error = SET_ERROR(EINVAL);
4888                         break;
4889                 }
4890 
4891                 if (vdev_dtl_required(vml[c])) {
4892                         error = SET_ERROR(EBUSY);
4893                         break;
4894                 }
4895 
4896                 /* we need certain info from the top level */
4897                 VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_METASLAB_ARRAY,
4898                     vml[c]->vdev_top->vdev_ms_array) == 0);
4899                 VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_METASLAB_SHIFT,
4900                     vml[c]->vdev_top->vdev_ms_shift) == 0);
4901                 VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_ASIZE,
4902                     vml[c]->vdev_top->vdev_asize) == 0);
4903                 VERIFY(nvlist_add_uint64(child[c], ZPOOL_CONFIG_ASHIFT,
4904                     vml[c]->vdev_top->vdev_ashift) == 0);
4905         }
4906 
4907         if (error != 0) {
4908                 kmem_free(vml, children * sizeof (vdev_t *));
4909                 kmem_free(glist, children * sizeof (uint64_t));
4910                 return (spa_vdev_exit(spa, NULL, txg, error));
4911         }
4912 
4913         /* stop writers from using the disks */
4914         for (c = 0; c < children; c++) {
4915                 if (vml[c] != NULL)
4916                         vml[c]->vdev_offline = B_TRUE;
4917         }
4918         vdev_reopen(spa->spa_root_vdev);
4919 
4920         /*
4921          * Temporarily record the splitting vdevs in the spa config.  This
4922          * will disappear once the config is regenerated.
4923          */
4924         VERIFY(nvlist_alloc(&nvl, NV_UNIQUE_NAME, KM_SLEEP) == 0);
4925         VERIFY(nvlist_add_uint64_array(nvl, ZPOOL_CONFIG_SPLIT_LIST,
4926             glist, children) == 0);
4927         kmem_free(glist, children * sizeof (uint64_t));
4928 
4929         mutex_enter(&spa->spa_props_lock);
4930         VERIFY(nvlist_add_nvlist(spa->spa_config, ZPOOL_CONFIG_SPLIT,
4931             nvl) == 0);
4932         mutex_exit(&spa->spa_props_lock);
4933         spa->spa_config_splitting = nvl;
4934         vdev_config_dirty(spa->spa_root_vdev);
4935 
4936         /* configure and create the new pool */
4937         VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, newname) == 0);
4938         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
4939             exp ? POOL_STATE_EXPORTED : POOL_STATE_ACTIVE) == 0);
4940         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION,
4941             spa_version(spa)) == 0);
4942         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG,
4943             spa->spa_config_txg) == 0);
4944         VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID,
4945             spa_generate_guid(NULL)) == 0);
4946         (void) nvlist_lookup_string(props,
4947             zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
4948 
4949         /* add the new pool to the namespace */
4950         newspa = spa_add(newname, config, altroot);
4951         newspa->spa_config_txg = spa->spa_config_txg;
4952         spa_set_log_state(newspa, SPA_LOG_CLEAR);
4953 
4954         /* release the spa config lock, retaining the namespace lock */
4955         spa_vdev_config_exit(spa, NULL, txg, 0, FTAG);
4956 
4957         if (zio_injection_enabled)
4958                 zio_handle_panic_injection(spa, FTAG, 1);
4959 
4960         spa_activate(newspa, spa_mode_global);
4961         spa_async_suspend(newspa);
4962 
4963         /* create the new pool from the disks of the original pool */
4964         error = spa_load(newspa, SPA_LOAD_IMPORT, SPA_IMPORT_ASSEMBLE, B_TRUE);
4965         if (error)
4966                 goto out;
4967 
4968         /* if that worked, generate a real config for the new pool */
4969         if (newspa->spa_root_vdev != NULL) {
4970                 VERIFY(nvlist_alloc(&newspa->spa_config_splitting,
4971                     NV_UNIQUE_NAME, KM_SLEEP) == 0);
4972                 VERIFY(nvlist_add_uint64(newspa->spa_config_splitting,
4973                     ZPOOL_CONFIG_SPLIT_GUID, spa_guid(spa)) == 0);
4974                 spa_config_set(newspa, spa_config_generate(newspa, NULL, -1ULL,
4975                     B_TRUE));
4976         }
4977 
4978         /* set the props */
4979         if (props != NULL) {
4980                 spa_configfile_set(newspa, props, B_FALSE);
4981                 error = spa_prop_set(newspa, props);
4982                 if (error)
4983                         goto out;
4984         }
4985 
4986         /* flush everything */
4987         txg = spa_vdev_config_enter(newspa);
4988         vdev_config_dirty(newspa->spa_root_vdev);
4989         (void) spa_vdev_config_exit(newspa, NULL, txg, 0, FTAG);
4990 
4991         if (zio_injection_enabled)
4992                 zio_handle_panic_injection(spa, FTAG, 2);
4993 
4994         spa_async_resume(newspa);
4995 
4996         /* finally, update the original pool's config */
4997         txg = spa_vdev_config_enter(spa);
4998         tx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir);
4999         error = dmu_tx_assign(tx, TXG_WAIT);
5000         if (error != 0)
5001                 dmu_tx_abort(tx);
5002         for (c = 0; c < children; c++) {
5003                 if (vml[c] != NULL) {
5004                         vdev_split(vml[c]);
5005                         if (error == 0)
5006                                 spa_history_log_internal(spa, "detach", tx,
5007                                     "vdev=%s", vml[c]->vdev_path);
5008                         vdev_free(vml[c]);
5009                 }
5010         }
5011         vdev_config_dirty(spa->spa_root_vdev);
5012         spa->spa_config_splitting = NULL;
5013         nvlist_free(nvl);
5014         if (error == 0)
5015                 dmu_tx_commit(tx);
5016         (void) spa_vdev_exit(spa, NULL, txg, 0);
5017 
5018         if (zio_injection_enabled)
5019                 zio_handle_panic_injection(spa, FTAG, 3);
5020 
5021         /* split is complete; log a history record */
5022         spa_history_log_internal(newspa, "split", NULL,
5023             "from pool %s", spa_name(spa));
5024 
5025         kmem_free(vml, children * sizeof (vdev_t *));
5026 
5027         /* if we're not going to mount the filesystems in userland, export */
5028         if (exp)
5029                 error = spa_export_common(newname, POOL_STATE_EXPORTED, NULL,
5030                     B_FALSE, B_FALSE);
5031 
5032         return (error);
5033 
5034 out:
5035         spa_unload(newspa);
5036         spa_deactivate(newspa);
5037         spa_remove(newspa);
5038 
5039         txg = spa_vdev_config_enter(spa);
5040 
5041         /* re-online all offlined disks */
5042         for (c = 0; c < children; c++) {
5043                 if (vml[c] != NULL)
5044                         vml[c]->vdev_offline = B_FALSE;
5045         }
5046         vdev_reopen(spa->spa_root_vdev);
5047 
5048         nvlist_free(spa->spa_config_splitting);
5049         spa->spa_config_splitting = NULL;
5050         (void) spa_vdev_exit(spa, NULL, txg, error);
5051 
5052         kmem_free(vml, children * sizeof (vdev_t *));
5053         return (error);
5054 }
5055 
5056 static nvlist_t *
5057 spa_nvlist_lookup_by_guid(nvlist_t **nvpp, int count, uint64_t target_guid)
5058 {
5059         for (int i = 0; i < count; i++) {
5060                 uint64_t guid;
5061 
5062                 VERIFY(nvlist_lookup_uint64(nvpp[i], ZPOOL_CONFIG_GUID,
5063                     &guid) == 0);
5064 
5065                 if (guid == target_guid)
5066                         return (nvpp[i]);
5067         }
5068 
5069         return (NULL);
5070 }
5071 
5072 static void
5073 spa_vdev_remove_aux(nvlist_t *config, char *name, nvlist_t **dev, int count,
5074         nvlist_t *dev_to_remove)
5075 {
5076         nvlist_t **newdev = NULL;
5077 
5078         if (count > 1)
5079                 newdev = kmem_alloc((count - 1) * sizeof (void *), KM_SLEEP);
5080 
5081         for (int i = 0, j = 0; i < count; i++) {
5082                 if (dev[i] == dev_to_remove)
5083                         continue;
5084                 VERIFY(nvlist_dup(dev[i], &newdev[j++], KM_SLEEP) == 0);
5085         }
5086 
5087         VERIFY(nvlist_remove(config, name, DATA_TYPE_NVLIST_ARRAY) == 0);
5088         VERIFY(nvlist_add_nvlist_array(config, name, newdev, count - 1) == 0);
5089 
5090         for (int i = 0; i < count - 1; i++)
5091                 nvlist_free(newdev[i]);
5092 
5093         if (count > 1)
5094                 kmem_free(newdev, (count - 1) * sizeof (void *));
5095 }
5096 
5097 /*
5098  * Evacuate the device.
5099  */
5100 static int
5101 spa_vdev_remove_evacuate(spa_t *spa, vdev_t *vd)
5102 {
5103         uint64_t txg;
5104         int error = 0;
5105 
5106         ASSERT(MUTEX_HELD(&spa_namespace_lock));
5107         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == 0);
5108         ASSERT(vd == vd->vdev_top);
5109 
5110         /*
5111          * Evacuate the device.  We don't hold the config lock as writer
5112          * since we need to do I/O but we do keep the
5113          * spa_namespace_lock held.  Once this completes the device
5114          * should no longer have any blocks allocated on it.
5115          */
5116         if (vd->vdev_islog) {
5117                 if (vd->vdev_stat.vs_alloc != 0)
5118                         error = spa_offline_log(spa);
5119         } else {
5120                 error = SET_ERROR(ENOTSUP);
5121         }
5122 
5123         if (error)
5124                 return (error);
5125 
5126         /*
5127          * The evacuation succeeded.  Remove any remaining MOS metadata
5128          * associated with this vdev, and wait for these changes to sync.
5129          */
5130         ASSERT0(vd->vdev_stat.vs_alloc);
5131         txg = spa_vdev_config_enter(spa);
5132         vd->vdev_removing = B_TRUE;
5133         vdev_dirty_leaves(vd, VDD_DTL, txg);
5134         vdev_config_dirty(vd);
5135         spa_vdev_config_exit(spa, NULL, txg, 0, FTAG);
5136 
5137         return (0);
5138 }
5139 
5140 /*
5141  * Complete the removal by cleaning up the namespace.
5142  */
5143 static void
5144 spa_vdev_remove_from_namespace(spa_t *spa, vdev_t *vd)
5145 {
5146         vdev_t *rvd = spa->spa_root_vdev;
5147         uint64_t id = vd->vdev_id;
5148         boolean_t last_vdev = (id == (rvd->vdev_children - 1));
5149 
5150         ASSERT(MUTEX_HELD(&spa_namespace_lock));
5151         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
5152         ASSERT(vd == vd->vdev_top);
5153 
5154         /*
5155          * Only remove any devices which are empty.
5156          */
5157         if (vd->vdev_stat.vs_alloc != 0)
5158                 return;
5159 
5160         (void) vdev_label_init(vd, 0, VDEV_LABEL_REMOVE);
5161 
5162         if (list_link_active(&vd->vdev_state_dirty_node))
5163                 vdev_state_clean(vd);
5164         if (list_link_active(&vd->vdev_config_dirty_node))
5165                 vdev_config_clean(vd);
5166 
5167         vdev_free(vd);
5168 
5169         if (last_vdev) {
5170                 vdev_compact_children(rvd);
5171         } else {
5172                 vd = vdev_alloc_common(spa, id, 0, &vdev_hole_ops);
5173                 vdev_add_child(rvd, vd);
5174         }
5175         vdev_config_dirty(rvd);
5176 
5177         /*
5178          * Reassess the health of our root vdev.
5179          */
5180         vdev_reopen(rvd);
5181 }
5182 
5183 /*
5184  * Remove a device from the pool -
5185  *
5186  * Removing a device from the vdev namespace requires several steps
5187  * and can take a significant amount of time.  As a result we use
5188  * the spa_vdev_config_[enter/exit] functions which allow us to
5189  * grab and release the spa_config_lock while still holding the namespace
5190  * lock.  During each step the configuration is synced out.
5191  *
5192  * Currently, this supports removing only hot spares, slogs, and level 2 ARC
5193  * devices.
5194  */
5195 int
5196 spa_vdev_remove(spa_t *spa, uint64_t guid, boolean_t unspare)
5197 {
5198         vdev_t *vd;
5199         metaslab_group_t *mg;
5200         nvlist_t **spares, **l2cache, *nv;
5201         uint64_t txg = 0;
5202         uint_t nspares, nl2cache;
5203         int error = 0;
5204         boolean_t locked = MUTEX_HELD(&spa_namespace_lock);
5205 
5206         ASSERT(spa_writeable(spa));
5207 
5208         if (!locked)
5209                 txg = spa_vdev_enter(spa);
5210 
5211         vd = spa_lookup_by_guid(spa, guid, B_FALSE);
5212 
5213         if (spa->spa_spares.sav_vdevs != NULL &&
5214             nvlist_lookup_nvlist_array(spa->spa_spares.sav_config,
5215             ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0 &&
5216             (nv = spa_nvlist_lookup_by_guid(spares, nspares, guid)) != NULL) {
5217                 /*
5218                  * Only remove the hot spare if it's not currently in use
5219                  * in this pool.
5220                  */
5221                 if (vd == NULL || unspare) {
5222                         spa_vdev_remove_aux(spa->spa_spares.sav_config,
5223                             ZPOOL_CONFIG_SPARES, spares, nspares, nv);
5224                         spa_load_spares(spa);
5225                         spa->spa_spares.sav_sync = B_TRUE;
5226                 } else {
5227                         error = SET_ERROR(EBUSY);
5228                 }
5229         } else if (spa->spa_l2cache.sav_vdevs != NULL &&
5230             nvlist_lookup_nvlist_array(spa->spa_l2cache.sav_config,
5231             ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0 &&
5232             (nv = spa_nvlist_lookup_by_guid(l2cache, nl2cache, guid)) != NULL) {
5233                 /*
5234                  * Cache devices can always be removed.
5235                  */
5236                 spa_vdev_remove_aux(spa->spa_l2cache.sav_config,
5237                     ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache, nv);
5238                 spa_load_l2cache(spa);
5239                 spa->spa_l2cache.sav_sync = B_TRUE;
5240         } else if (vd != NULL && vd->vdev_islog) {
5241                 ASSERT(!locked);
5242                 ASSERT(vd == vd->vdev_top);
5243 
5244                 /*
5245                  * XXX - Once we have bp-rewrite this should
5246                  * become the common case.
5247                  */
5248 
5249                 mg = vd->vdev_mg;
5250 
5251                 /*
5252                  * Stop allocating from this vdev.
5253                  */
5254                 metaslab_group_passivate(mg);
5255 
5256                 /*
5257                  * Wait for the youngest allocations and frees to sync,
5258                  * and then wait for the deferral of those frees to finish.
5259                  */
5260                 spa_vdev_config_exit(spa, NULL,
5261                     txg + TXG_CONCURRENT_STATES + TXG_DEFER_SIZE, 0, FTAG);
5262 
5263                 /*
5264                  * Attempt to evacuate the vdev.
5265                  */
5266                 error = spa_vdev_remove_evacuate(spa, vd);
5267 
5268                 txg = spa_vdev_config_enter(spa);
5269 
5270                 /*
5271                  * If we couldn't evacuate the vdev, unwind.
5272                  */
5273                 if (error) {
5274                         metaslab_group_activate(mg);
5275                         return (spa_vdev_exit(spa, NULL, txg, error));
5276                 }
5277 
5278                 /*
5279                  * Clean up the vdev namespace.
5280                  */
5281                 spa_vdev_remove_from_namespace(spa, vd);
5282 
5283         } else if (vd != NULL) {
5284                 /*
5285                  * Normal vdevs cannot be removed (yet).
5286                  */
5287                 error = SET_ERROR(ENOTSUP);
5288         } else {
5289                 /*
5290                  * There is no vdev of any kind with the specified guid.
5291                  */
5292                 error = SET_ERROR(ENOENT);
5293         }
5294 
5295         if (!locked)
5296                 return (spa_vdev_exit(spa, NULL, txg, error));
5297 
5298         return (error);
5299 }
5300 
5301 /*
5302  * Find any device that's done replacing, or a vdev marked 'unspare' that's
5303  * currently spared, so we can detach it.
5304  */
5305 static vdev_t *
5306 spa_vdev_resilver_done_hunt(vdev_t *vd)
5307 {
5308         vdev_t *newvd, *oldvd;
5309 
5310         for (int c = 0; c < vd->vdev_children; c++) {
5311                 oldvd = spa_vdev_resilver_done_hunt(vd->vdev_child[c]);
5312                 if (oldvd != NULL)
5313                         return (oldvd);
5314         }
5315 
5316         /*
5317          * Check for a completed replacement.  We always consider the first
5318          * vdev in the list to be the oldest vdev, and the last one to be
5319          * the newest (see spa_vdev_attach() for how that works).  In
5320          * the case where the newest vdev is faulted, we will not automatically
5321          * remove it after a resilver completes.  This is OK as it will require
5322          * user intervention to determine which disk the admin wishes to keep.
5323          */
5324         if (vd->vdev_ops == &vdev_replacing_ops) {
5325                 ASSERT(vd->vdev_children > 1);
5326 
5327                 newvd = vd->vdev_child[vd->vdev_children - 1];
5328                 oldvd = vd->vdev_child[0];
5329 
5330                 if (vdev_dtl_empty(newvd, DTL_MISSING) &&
5331                     vdev_dtl_empty(newvd, DTL_OUTAGE) &&
5332                     !vdev_dtl_required(oldvd))
5333                         return (oldvd);
5334         }
5335 
5336         /*
5337          * Check for a completed resilver with the 'unspare' flag set.
5338          */
5339         if (vd->vdev_ops == &vdev_spare_ops) {
5340                 vdev_t *first = vd->vdev_child[0];
5341                 vdev_t *last = vd->vdev_child[vd->vdev_children - 1];
5342 
5343                 if (last->vdev_unspare) {
5344                         oldvd = first;
5345                         newvd = last;
5346                 } else if (first->vdev_unspare) {
5347                         oldvd = last;
5348                         newvd = first;
5349                 } else {
5350                         oldvd = NULL;
5351                 }
5352 
5353                 if (oldvd != NULL &&
5354                     vdev_dtl_empty(newvd, DTL_MISSING) &&
5355                     vdev_dtl_empty(newvd, DTL_OUTAGE) &&
5356                     !vdev_dtl_required(oldvd))
5357                         return (oldvd);
5358 
5359                 /*
5360                  * If there are more than two spares attached to a disk,
5361                  * and those spares are not required, then we want to
5362                  * attempt to free them up now so that they can be used
5363                  * by other pools.  Once we're back down to a single
5364                  * disk+spare, we stop removing them.
5365                  */
5366                 if (vd->vdev_children > 2) {
5367                         newvd = vd->vdev_child[1];
5368 
5369                         if (newvd->vdev_isspare && last->vdev_isspare &&
5370                             vdev_dtl_empty(last, DTL_MISSING) &&
5371                             vdev_dtl_empty(last, DTL_OUTAGE) &&
5372                             !vdev_dtl_required(newvd))
5373                                 return (newvd);
5374                 }
5375         }
5376 
5377         return (NULL);
5378 }
5379 
5380 static void
5381 spa_vdev_resilver_done(spa_t *spa)
5382 {
5383         vdev_t *vd, *pvd, *ppvd;
5384         uint64_t guid, sguid, pguid, ppguid;
5385 
5386         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
5387 
5388         while ((vd = spa_vdev_resilver_done_hunt(spa->spa_root_vdev)) != NULL) {
5389                 pvd = vd->vdev_parent;
5390                 ppvd = pvd->vdev_parent;
5391                 guid = vd->vdev_guid;
5392                 pguid = pvd->vdev_guid;
5393                 ppguid = ppvd->vdev_guid;
5394                 sguid = 0;
5395                 /*
5396                  * If we have just finished replacing a hot spared device, then
5397                  * we need to detach the parent's first child (the original hot
5398                  * spare) as well.
5399                  */
5400                 if (ppvd->vdev_ops == &vdev_spare_ops && pvd->vdev_id == 0 &&
5401                     ppvd->vdev_children == 2) {
5402                         ASSERT(pvd->vdev_ops == &vdev_replacing_ops);
5403                         sguid = ppvd->vdev_child[1]->vdev_guid;
5404                 }
5405                 ASSERT(vd->vdev_resilver_txg == 0 || !vdev_dtl_required(vd));
5406 
5407                 spa_config_exit(spa, SCL_ALL, FTAG);
5408                 if (spa_vdev_detach(spa, guid, pguid, B_TRUE) != 0)
5409                         return;
5410                 if (sguid && spa_vdev_detach(spa, sguid, ppguid, B_TRUE) != 0)
5411                         return;
5412                 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
5413         }
5414 
5415         spa_config_exit(spa, SCL_ALL, FTAG);
5416 }
5417 
5418 /*
5419  * Update the stored path or FRU for this vdev.
5420  */
5421 int
5422 spa_vdev_set_common(spa_t *spa, uint64_t guid, const char *value,
5423     boolean_t ispath)
5424 {
5425         vdev_t *vd;
5426         boolean_t sync = B_FALSE;
5427 
5428         ASSERT(spa_writeable(spa));
5429 
5430         spa_vdev_state_enter(spa, SCL_ALL);
5431 
5432         if ((vd = spa_lookup_by_guid(spa, guid, B_TRUE)) == NULL)
5433                 return (spa_vdev_state_exit(spa, NULL, ENOENT));
5434 
5435         if (!vd->vdev_ops->vdev_op_leaf)
5436                 return (spa_vdev_state_exit(spa, NULL, ENOTSUP));
5437 
5438         if (ispath) {
5439                 if (strcmp(value, vd->vdev_path) != 0) {
5440                         spa_strfree(vd->vdev_path);
5441                         vd->vdev_path = spa_strdup(value);
5442                         sync = B_TRUE;
5443                 }
5444         } else {
5445                 if (vd->vdev_fru == NULL) {
5446                         vd->vdev_fru = spa_strdup(value);
5447                         sync = B_TRUE;
5448                 } else if (strcmp(value, vd->vdev_fru) != 0) {
5449                         spa_strfree(vd->vdev_fru);
5450                         vd->vdev_fru = spa_strdup(value);
5451                         sync = B_TRUE;
5452                 }
5453         }
5454 
5455         return (spa_vdev_state_exit(spa, sync ? vd : NULL, 0));
5456 }
5457 
5458 int
5459 spa_vdev_setpath(spa_t *spa, uint64_t guid, const char *newpath)
5460 {
5461         return (spa_vdev_set_common(spa, guid, newpath, B_TRUE));
5462 }
5463 
5464 int
5465 spa_vdev_setfru(spa_t *spa, uint64_t guid, const char *newfru)
5466 {
5467         return (spa_vdev_set_common(spa, guid, newfru, B_FALSE));
5468 }
5469 
5470 /*
5471  * ==========================================================================
5472  * SPA Scanning
5473  * ==========================================================================
5474  */
5475 
5476 int
5477 spa_scan_stop(spa_t *spa)
5478 {
5479         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == 0);
5480         if (dsl_scan_resilvering(spa->spa_dsl_pool))
5481                 return (SET_ERROR(EBUSY));
5482         return (dsl_scan_cancel(spa->spa_dsl_pool));
5483 }
5484 
5485 int
5486 spa_scan(spa_t *spa, pool_scan_func_t func)
5487 {
5488         ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == 0);
5489 
5490         if (func >= POOL_SCAN_FUNCS || func == POOL_SCAN_NONE)
5491                 return (SET_ERROR(ENOTSUP));
5492 
5493         /*
5494          * If a resilver was requested, but there is no DTL on a
5495          * writeable leaf device, we have nothing to do.
5496          */
5497         if (func == POOL_SCAN_RESILVER &&
5498             !vdev_resilver_needed(spa->spa_root_vdev, NULL, NULL)) {
5499                 spa_async_request(spa, SPA_ASYNC_RESILVER_DONE);
5500                 return (0);
5501         }
5502 
5503         return (dsl_scan(spa->spa_dsl_pool, func));
5504 }
5505 
5506 /*
5507  * ==========================================================================
5508  * SPA async task processing
5509  * ==========================================================================
5510  */
5511 
5512 static void
5513 spa_async_remove(spa_t *spa, vdev_t *vd)
5514 {
5515         if (vd->vdev_remove_wanted) {
5516                 vd->vdev_remove_wanted = B_FALSE;
5517                 vd->vdev_delayed_close = B_FALSE;
5518                 vdev_set_state(vd, B_FALSE, VDEV_STATE_REMOVED, VDEV_AUX_NONE);
5519 
5520                 /*
5521                  * We want to clear the stats, but we don't want to do a full
5522                  * vdev_clear() as that will cause us to throw away
5523                  * degraded/faulted state as well as attempt to reopen the
5524                  * device, all of which is a waste.
5525                  */
5526                 vd->vdev_stat.vs_read_errors = 0;
5527                 vd->vdev_stat.vs_write_errors = 0;
5528                 vd->vdev_stat.vs_checksum_errors = 0;
5529 
5530                 vdev_state_dirty(vd->vdev_top);
5531         }
5532 
5533         for (int c = 0; c < vd->vdev_children; c++)
5534                 spa_async_remove(spa, vd->vdev_child[c]);
5535 }
5536 
5537 static void
5538 spa_async_probe(spa_t *spa, vdev_t *vd)
5539 {
5540         if (vd->vdev_probe_wanted) {
5541                 vd->vdev_probe_wanted = B_FALSE;
5542                 vdev_reopen(vd);        /* vdev_open() does the actual probe */
5543         }
5544 
5545         for (int c = 0; c < vd->vdev_children; c++)
5546                 spa_async_probe(spa, vd->vdev_child[c]);
5547 }
5548 
5549 static void
5550 spa_async_autoexpand(spa_t *spa, vdev_t *vd)
5551 {
5552         sysevent_id_t eid;
5553         nvlist_t *attr;
5554         char *physpath;
5555 
5556         if (!spa->spa_autoexpand)
5557                 return;
5558 
5559         for (int c = 0; c < vd->vdev_children; c++) {
5560                 vdev_t *cvd = vd->vdev_child[c];
5561                 spa_async_autoexpand(spa, cvd);
5562         }
5563 
5564         if (!vd->vdev_ops->vdev_op_leaf || vd->vdev_physpath == NULL)
5565                 return;
5566 
5567         physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
5568         (void) snprintf(physpath, MAXPATHLEN, "/devices%s", vd->vdev_physpath);
5569 
5570         VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
5571         VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
5572 
5573         (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
5574             ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
5575 
5576         nvlist_free(attr);
5577         kmem_free(physpath, MAXPATHLEN);
5578 }
5579 
5580 static void
5581 spa_async_thread(spa_t *spa)
5582 {
5583         int tasks;
5584 
5585         ASSERT(spa->spa_sync_on);
5586 
5587         mutex_enter(&spa->spa_async_lock);
5588         tasks = spa->spa_async_tasks;
5589         spa->spa_async_tasks = 0;
5590         mutex_exit(&spa->spa_async_lock);
5591 
5592         /*
5593          * See if the config needs to be updated.
5594          */
5595         if (tasks & SPA_ASYNC_CONFIG_UPDATE) {
5596                 uint64_t old_space, new_space;
5597 
5598                 mutex_enter(&spa_namespace_lock);
5599                 old_space = metaslab_class_get_space(spa_normal_class(spa));
5600                 spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
5601                 new_space = metaslab_class_get_space(spa_normal_class(spa));
5602                 mutex_exit(&spa_namespace_lock);
5603 
5604                 /*
5605                  * If the pool grew as a result of the config update,
5606                  * then log an internal history event.
5607                  */
5608                 if (new_space != old_space) {
5609                         spa_history_log_internal(spa, "vdev online", NULL,
5610                             "pool '%s' size: %llu(+%llu)",
5611                             spa_name(spa), new_space, new_space - old_space);
5612                 }
5613         }
5614 
5615         /*
5616          * See if any devices need to be marked REMOVED.
5617          */
5618         if (tasks & SPA_ASYNC_REMOVE) {
5619                 spa_vdev_state_enter(spa, SCL_NONE);
5620                 spa_async_remove(spa, spa->spa_root_vdev);
5621                 for (int i = 0; i < spa->spa_l2cache.sav_count; i++)
5622                         spa_async_remove(spa, spa->spa_l2cache.sav_vdevs[i]);
5623                 for (int i = 0; i < spa->spa_spares.sav_count; i++)
5624                         spa_async_remove(spa, spa->spa_spares.sav_vdevs[i]);
5625                 (void) spa_vdev_state_exit(spa, NULL, 0);
5626         }
5627 
5628         if ((tasks & SPA_ASYNC_AUTOEXPAND) && !spa_suspended(spa)) {
5629                 spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
5630                 spa_async_autoexpand(spa, spa->spa_root_vdev);
5631                 spa_config_exit(spa, SCL_CONFIG, FTAG);
5632         }
5633 
5634         /*
5635          * See if any devices need to be probed.
5636          */
5637         if (tasks & SPA_ASYNC_PROBE) {
5638                 spa_vdev_state_enter(spa, SCL_NONE);
5639                 spa_async_probe(spa, spa->spa_root_vdev);
5640                 (void) spa_vdev_state_exit(spa, NULL, 0);
5641         }
5642 
5643         /*
5644          * If any devices are done replacing, detach them.
5645          */
5646         if (tasks & SPA_ASYNC_RESILVER_DONE)
5647                 spa_vdev_resilver_done(spa);
5648 
5649         /*
5650          * Kick off a resilver.
5651          */
5652         if (tasks & SPA_ASYNC_RESILVER)
5653                 dsl_resilver_restart(spa->spa_dsl_pool, 0);
5654 
5655         /*
5656          * Kick off L2 cache rebuilding.
5657          */
5658         if (tasks & SPA_ASYNC_L2CACHE_REBUILD)
5659                 l2arc_spa_rebuild_start(spa);
5660 
5661         /*
5662          * Let the world know that we're done.
5663          */
5664         mutex_enter(&spa->spa_async_lock);
5665         spa->spa_async_thread = NULL;
5666         cv_broadcast(&spa->spa_async_cv);
5667         mutex_exit(&spa->spa_async_lock);
5668         thread_exit();
5669 }
5670 
5671 void
5672 spa_async_suspend(spa_t *spa)
5673 {
5674         mutex_enter(&spa->spa_async_lock);
5675         spa->spa_async_suspended++;
5676         while (spa->spa_async_thread != NULL)
5677                 cv_wait(&spa->spa_async_cv, &spa->spa_async_lock);
5678         mutex_exit(&spa->spa_async_lock);
5679 }
5680 
5681 void
5682 spa_async_resume(spa_t *spa)
5683 {
5684         mutex_enter(&spa->spa_async_lock);
5685         ASSERT(spa->spa_async_suspended != 0);
5686         spa->spa_async_suspended--;
5687         mutex_exit(&spa->spa_async_lock);
5688 }
5689 
5690 static boolean_t
5691 spa_async_tasks_pending(spa_t *spa)
5692 {
5693         uint_t non_config_tasks;
5694         uint_t config_task;
5695         boolean_t config_task_suspended;
5696 
5697         non_config_tasks = spa->spa_async_tasks & ~SPA_ASYNC_CONFIG_UPDATE;
5698         config_task = spa->spa_async_tasks & SPA_ASYNC_CONFIG_UPDATE;
5699         if (spa->spa_ccw_fail_time == 0) {
5700                 config_task_suspended = B_FALSE;
5701         } else {
5702                 config_task_suspended =
5703                     (gethrtime() - spa->spa_ccw_fail_time) <
5704                     (zfs_ccw_retry_interval * NANOSEC);
5705         }
5706 
5707         return (non_config_tasks || (config_task && !config_task_suspended));
5708 }
5709 
5710 static void
5711 spa_async_dispatch(spa_t *spa)
5712 {
5713         mutex_enter(&spa->spa_async_lock);
5714         if (spa_async_tasks_pending(spa) &&
5715             !spa->spa_async_suspended &&
5716             spa->spa_async_thread == NULL &&
5717             rootdir != NULL)
5718                 spa->spa_async_thread = thread_create(NULL, 0,
5719                     spa_async_thread, spa, 0, &p0, TS_RUN, maxclsyspri);
5720         mutex_exit(&spa->spa_async_lock);
5721 }
5722 
5723 void
5724 spa_async_request(spa_t *spa, int task)
5725 {
5726         zfs_dbgmsg("spa=%s async request task=%u", spa->spa_name, task);
5727         mutex_enter(&spa->spa_async_lock);
5728         spa->spa_async_tasks |= task;
5729         mutex_exit(&spa->spa_async_lock);
5730 }
5731 
5732 /*
5733  * ==========================================================================
5734  * SPA syncing routines
5735  * ==========================================================================
5736  */
5737 
5738 static int
5739 bpobj_enqueue_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
5740 {
5741         bpobj_t *bpo = arg;
5742         bpobj_enqueue(bpo, bp, tx);
5743         return (0);
5744 }
5745 
5746 static int
5747 spa_free_sync_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
5748 {
5749         zio_t *zio = arg;
5750 
5751         zio_nowait(zio_free_sync(zio, zio->io_spa, dmu_tx_get_txg(tx), bp,
5752             zio->io_flags));
5753         return (0);
5754 }
5755 
5756 /*
5757  * Note: this simple function is not inlined to make it easier to dtrace the
5758  * amount of time spent syncing frees.
5759  */
5760 static void
5761 spa_sync_frees(spa_t *spa, bplist_t *bpl, dmu_tx_t *tx)
5762 {
5763         zio_t *zio = zio_root(spa, NULL, NULL, 0);
5764         bplist_iterate(bpl, spa_free_sync_cb, zio, tx);
5765         VERIFY(zio_wait(zio) == 0);
5766 }
5767 
5768 /*
5769  * Note: this simple function is not inlined to make it easier to dtrace the
5770  * amount of time spent syncing deferred frees.
5771  */
5772 static void
5773 spa_sync_deferred_frees(spa_t *spa, dmu_tx_t *tx)
5774 {
5775         zio_t *zio = zio_root(spa, NULL, NULL, 0);
5776         VERIFY3U(bpobj_iterate(&spa->spa_deferred_bpobj,
5777             spa_free_sync_cb, zio, tx), ==, 0);
5778         VERIFY0(zio_wait(zio));
5779 }
5780 
5781 
5782 static void
5783 spa_sync_nvlist(spa_t *spa, uint64_t obj, nvlist_t *nv, dmu_tx_t *tx)
5784 {
5785         char *packed = NULL;
5786         size_t bufsize;
5787         size_t nvsize = 0;
5788         dmu_buf_t *db;
5789 
5790         VERIFY(nvlist_size(nv, &nvsize, NV_ENCODE_XDR) == 0);
5791 
5792         /*
5793          * Write full (SPA_CONFIG_BLOCKSIZE) blocks of configuration
5794          * information.  This avoids the dbuf_will_dirty() path and
5795          * saves us a pre-read to get data we don't actually care about.
5796          */
5797         bufsize = P2ROUNDUP((uint64_t)nvsize, SPA_CONFIG_BLOCKSIZE);
5798         packed = kmem_alloc(bufsize, KM_SLEEP);
5799 
5800         VERIFY(nvlist_pack(nv, &packed, &nvsize, NV_ENCODE_XDR,
5801             KM_SLEEP) == 0);
5802         bzero(packed + nvsize, bufsize - nvsize);
5803 
5804         dmu_write(spa->spa_meta_objset, obj, 0, bufsize, packed, tx);
5805 
5806         kmem_free(packed, bufsize);
5807 
5808         VERIFY(0 == dmu_bonus_hold(spa->spa_meta_objset, obj, FTAG, &db));
5809         dmu_buf_will_dirty(db, tx);
5810         *(uint64_t *)db->db_data = nvsize;
5811         dmu_buf_rele(db, FTAG);
5812 }
5813 
5814 static void
5815 spa_sync_aux_dev(spa_t *spa, spa_aux_vdev_t *sav, dmu_tx_t *tx,
5816     const char *config, const char *entry)
5817 {
5818         nvlist_t *nvroot;
5819         nvlist_t **list;
5820         int i;
5821 
5822         if (!sav->sav_sync)
5823                 return;
5824 
5825         /*
5826          * Update the MOS nvlist describing the list of available devices.
5827          * spa_validate_aux() will have already made sure this nvlist is
5828          * valid and the vdevs are labeled appropriately.
5829          */
5830         if (sav->sav_object == 0) {
5831                 sav->sav_object = dmu_object_alloc(spa->spa_meta_objset,
5832                     DMU_OT_PACKED_NVLIST, 1 << 14, DMU_OT_PACKED_NVLIST_SIZE,
5833                     sizeof (uint64_t), tx);
5834                 VERIFY(zap_update(spa->spa_meta_objset,
5835                     DMU_POOL_DIRECTORY_OBJECT, entry, sizeof (uint64_t), 1,
5836                     &sav->sav_object, tx) == 0);
5837         }
5838 
5839         VERIFY(nvlist_alloc(&nvroot, NV_UNIQUE_NAME, KM_SLEEP) == 0);
5840         if (sav->sav_count == 0) {
5841                 VERIFY(nvlist_add_nvlist_array(nvroot, config, NULL, 0) == 0);
5842         } else {
5843                 list = kmem_alloc(sav->sav_count * sizeof (void *), KM_SLEEP);
5844                 for (i = 0; i < sav->sav_count; i++)
5845                         list[i] = vdev_config_generate(spa, sav->sav_vdevs[i],
5846                             B_FALSE, VDEV_CONFIG_L2CACHE);
5847                 VERIFY(nvlist_add_nvlist_array(nvroot, config, list,
5848                     sav->sav_count) == 0);
5849                 for (i = 0; i < sav->sav_count; i++)
5850                         nvlist_free(list[i]);
5851                 kmem_free(list, sav->sav_count * sizeof (void *));
5852         }
5853 
5854         spa_sync_nvlist(spa, sav->sav_object, nvroot, tx);
5855         nvlist_free(nvroot);
5856 
5857         sav->sav_sync = B_FALSE;
5858 }
5859 
5860 static void
5861 spa_sync_config_object(spa_t *spa, dmu_tx_t *tx)
5862 {
5863         nvlist_t *config;
5864 
5865         if (list_is_empty(&spa->spa_config_dirty_list))
5866                 return;
5867 
5868         spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
5869 
5870         config = spa_config_generate(spa, spa->spa_root_vdev,
5871             dmu_tx_get_txg(tx), B_FALSE);
5872 
5873         /*
5874          * If we're upgrading the spa version then make sure that
5875          * the config object gets updated with the correct version.
5876          */
5877         if (spa->spa_ubsync.ub_version < spa->spa_uberblock.ub_version)
5878                 fnvlist_add_uint64(config, ZPOOL_CONFIG_VERSION,
5879                     spa->spa_uberblock.ub_version);
5880 
5881         spa_config_exit(spa, SCL_STATE, FTAG);
5882 
5883         if (spa->spa_config_syncing)
5884                 nvlist_free(spa->spa_config_syncing);
5885         spa->spa_config_syncing = config;
5886 
5887         spa_sync_nvlist(spa, spa->spa_config_object, config, tx);
5888 }
5889 
5890 static void
5891 spa_sync_version(void *arg, dmu_tx_t *tx)
5892 {
5893         uint64_t *versionp = arg;
5894         uint64_t version = *versionp;
5895         spa_t *spa = dmu_tx_pool(tx)->dp_spa;
5896 
5897         /*
5898          * Setting the version is special cased when first creating the pool.
5899          */
5900         ASSERT(tx->tx_txg != TXG_INITIAL);
5901 
5902         ASSERT(SPA_VERSION_IS_SUPPORTED(version));
5903         ASSERT(version >= spa_version(spa));
5904 
5905         spa->spa_uberblock.ub_version = version;
5906         vdev_config_dirty(spa->spa_root_vdev);
5907         spa_history_log_internal(spa, "set", tx, "version=%lld", version);
5908 }
5909 
5910 /*
5911  * Set zpool properties.
5912  */
5913 static void
5914 spa_sync_props(void *arg, dmu_tx_t *tx)
5915 {
5916         nvlist_t *nvp = arg;
5917         spa_t *spa = dmu_tx_pool(tx)->dp_spa;
5918         objset_t *mos = spa->spa_meta_objset;
5919         nvpair_t *elem = NULL;
5920 
5921         mutex_enter(&spa->spa_props_lock);
5922 
5923         while ((elem = nvlist_next_nvpair(nvp, elem))) {
5924                 uint64_t intval;
5925                 char *strval, *fname;
5926                 zpool_prop_t prop;
5927                 const char *propname;
5928                 zprop_type_t proptype;
5929                 spa_feature_t fid;
5930 
5931                 switch (prop = zpool_name_to_prop(nvpair_name(elem))) {
5932                 case ZPROP_INVAL:
5933                         /*
5934                          * We checked this earlier in spa_prop_validate().
5935                          */
5936                         ASSERT(zpool_prop_feature(nvpair_name(elem)));
5937 
5938                         fname = strchr(nvpair_name(elem), '@') + 1;
5939                         VERIFY0(zfeature_lookup_name(fname, &fid));
5940 
5941                         spa_feature_enable(spa, fid, tx);
5942                         spa_history_log_internal(spa, "set", tx,
5943                             "%s=enabled", nvpair_name(elem));
5944                         break;
5945 
5946                 case ZPOOL_PROP_VERSION:
5947                         intval = fnvpair_value_uint64(elem);
5948                         /*
5949                          * The version is synced seperatly before other
5950                          * properties and should be correct by now.
5951                          */
5952                         ASSERT3U(spa_version(spa), >=, intval);
5953                         break;
5954 
5955                 case ZPOOL_PROP_ALTROOT:
5956                         /*
5957                          * 'altroot' is a non-persistent property. It should
5958                          * have been set temporarily at creation or import time.
5959                          */
5960                         ASSERT(spa->spa_root != NULL);
5961                         break;
5962 
5963                 case ZPOOL_PROP_READONLY:
5964                 case ZPOOL_PROP_CACHEFILE:
5965                         /*
5966                          * 'readonly' and 'cachefile' are also non-persisitent
5967                          * properties.
5968                          */
5969                         break;
5970                 case ZPOOL_PROP_COMMENT:
5971                         strval = fnvpair_value_string(elem);
5972                         if (spa->spa_comment != NULL)
5973                                 spa_strfree(spa->spa_comment);
5974                         spa->spa_comment = spa_strdup(strval);
5975                         /*
5976                          * We need to dirty the configuration on all the vdevs
5977                          * so that their labels get updated.  It's unnecessary
5978                          * to do this for pool creation since the vdev's
5979                          * configuratoin has already been dirtied.
5980                          */
5981                         if (tx->tx_txg != TXG_INITIAL)
5982                                 vdev_config_dirty(spa->spa_root_vdev);
5983                         spa_history_log_internal(spa, "set", tx,
5984                             "%s=%s", nvpair_name(elem), strval);
5985                         break;
5986                 default:
5987                         /*
5988                          * Set pool property values in the poolprops mos object.
5989                          */
5990                         if (spa->spa_pool_props_object == 0) {
5991                                 spa->spa_pool_props_object =
5992                                     zap_create_link(mos, DMU_OT_POOL_PROPS,
5993                                     DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_PROPS,
5994                                     tx);
5995                         }
5996 
5997                         /* normalize the property name */
5998                         propname = zpool_prop_to_name(prop);
5999                         proptype = zpool_prop_get_type(prop);
6000 
6001                         if (nvpair_type(elem) == DATA_TYPE_STRING) {
6002                                 ASSERT(proptype == PROP_TYPE_STRING);
6003                                 strval = fnvpair_value_string(elem);
6004                                 VERIFY0(zap_update(mos,
6005                                     spa->spa_pool_props_object, propname,
6006                                     1, strlen(strval) + 1, strval, tx));
6007                                 spa_history_log_internal(spa, "set", tx,
6008                                     "%s=%s", nvpair_name(elem), strval);
6009                         } else if (nvpair_type(elem) == DATA_TYPE_UINT64) {
6010                                 intval = fnvpair_value_uint64(elem);
6011 
6012                                 if (proptype == PROP_TYPE_INDEX) {
6013                                         const char *unused;
6014                                         VERIFY0(zpool_prop_index_to_string(
6015                                             prop, intval, &unused));
6016                                 }
6017                                 VERIFY0(zap_update(mos,
6018                                     spa->spa_pool_props_object, propname,
6019                                     8, 1, &intval, tx));
6020                                 spa_history_log_internal(spa, "set", tx,
6021                                     "%s=%lld", nvpair_name(elem), intval);
6022                         } else {
6023                                 ASSERT(0); /* not allowed */
6024                         }
6025 
6026                         switch (prop) {
6027                         case ZPOOL_PROP_DELEGATION:
6028                                 spa->spa_delegation = intval;
6029                                 break;
6030                         case ZPOOL_PROP_BOOTFS:
6031                                 spa->spa_bootfs = intval;
6032                                 break;
6033                         case ZPOOL_PROP_FAILUREMODE:
6034                                 spa->spa_failmode = intval;
6035                                 break;
6036                         case ZPOOL_PROP_AUTOEXPAND:
6037                                 spa->spa_autoexpand = intval;
6038                                 if (tx->tx_txg != TXG_INITIAL)
6039                                         spa_async_request(spa,
6040                                             SPA_ASYNC_AUTOEXPAND);
6041                                 break;
6042                         case ZPOOL_PROP_DEDUPDITTO:
6043                                 spa->spa_dedup_ditto = intval;
6044                                 break;
6045                         default:
6046                                 break;
6047                         }
6048                 }
6049 
6050         }
6051 
6052         mutex_exit(&spa->spa_props_lock);
6053 }
6054 
6055 /*
6056  * Perform one-time upgrade on-disk changes.  spa_version() does not
6057  * reflect the new version this txg, so there must be no changes this
6058  * txg to anything that the upgrade code depends on after it executes.
6059  * Therefore this must be called after dsl_pool_sync() does the sync
6060  * tasks.
6061  */
6062 static void
6063 spa_sync_upgrades(spa_t *spa, dmu_tx_t *tx)
6064 {
6065         dsl_pool_t *dp = spa->spa_dsl_pool;
6066 
6067         ASSERT(spa->spa_sync_pass == 1);
6068 
6069         rrw_enter(&dp->dp_config_rwlock, RW_WRITER, FTAG);
6070 
6071         if (spa->spa_ubsync.ub_version < SPA_VERSION_ORIGIN &&
6072             spa->spa_uberblock.ub_version >= SPA_VERSION_ORIGIN) {
6073                 dsl_pool_create_origin(dp, tx);
6074 
6075                 /* Keeping the origin open increases spa_minref */
6076                 spa->spa_minref += 3;
6077         }
6078 
6079         if (spa->spa_ubsync.ub_version < SPA_VERSION_NEXT_CLONES &&
6080             spa->spa_uberblock.ub_version >= SPA_VERSION_NEXT_CLONES) {
6081                 dsl_pool_upgrade_clones(dp, tx);
6082         }
6083 
6084         if (spa->spa_ubsync.ub_version < SPA_VERSION_DIR_CLONES &&
6085             spa->spa_uberblock.ub_version >= SPA_VERSION_DIR_CLONES) {
6086                 dsl_pool_upgrade_dir_clones(dp, tx);
6087 
6088                 /* Keeping the freedir open increases spa_minref */
6089                 spa->spa_minref += 3;
6090         }
6091 
6092         if (spa->spa_ubsync.ub_version < SPA_VERSION_FEATURES &&
6093             spa->spa_uberblock.ub_version >= SPA_VERSION_FEATURES) {
6094                 spa_feature_create_zap_objects(spa, tx);
6095         }
6096         rrw_exit(&dp->dp_config_rwlock, FTAG);
6097 }
6098 
6099 /*
6100  * Sync the specified transaction group.  New blocks may be dirtied as
6101  * part of the process, so we iterate until it converges.
6102  */
6103 void
6104 spa_sync(spa_t *spa, uint64_t txg)
6105 {
6106         dsl_pool_t *dp = spa->spa_dsl_pool;
6107         objset_t *mos = spa->spa_meta_objset;
6108         bplist_t *free_bpl = &spa->spa_free_bplist[txg & TXG_MASK];
6109         vdev_t *rvd = spa->spa_root_vdev;
6110         vdev_t *vd;
6111         dmu_tx_t *tx;
6112         int error;
6113 
6114         VERIFY(spa_writeable(spa));
6115 
6116         /*
6117          * Lock out configuration changes.
6118          */
6119         spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
6120 
6121         spa->spa_syncing_txg = txg;
6122         spa->spa_sync_pass = 0;
6123 
6124         /*
6125          * If there are any pending vdev state changes, convert them
6126          * into config changes that go out with this transaction group.
6127          */
6128         spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
6129         while (list_head(&spa->spa_state_dirty_list) != NULL) {
6130                 /*
6131                  * We need the write lock here because, for aux vdevs,
6132                  * calling vdev_config_dirty() modifies sav_config.
6133                  * This is ugly and will become unnecessary when we
6134                  * eliminate the aux vdev wart by integrating all vdevs
6135                  * into the root vdev tree.
6136                  */
6137                 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
6138                 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_WRITER);
6139                 while ((vd = list_head(&spa->spa_state_dirty_list)) != NULL) {
6140                         vdev_state_clean(vd);
6141                         vdev_config_dirty(vd);
6142                 }
6143                 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
6144                 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER);
6145         }
6146         spa_config_exit(spa, SCL_STATE, FTAG);
6147 
6148         tx = dmu_tx_create_assigned(dp, txg);
6149 
6150         spa->spa_sync_starttime = gethrtime();
6151         VERIFY(cyclic_reprogram(spa->spa_deadman_cycid,
6152             spa->spa_sync_starttime + spa->spa_deadman_synctime));
6153 
6154         /*
6155          * If we are upgrading to SPA_VERSION_RAIDZ_DEFLATE this txg,
6156          * set spa_deflate if we have no raid-z vdevs.
6157          */
6158         if (spa->spa_ubsync.ub_version < SPA_VERSION_RAIDZ_DEFLATE &&
6159             spa->spa_uberblock.ub_version >= SPA_VERSION_RAIDZ_DEFLATE) {
6160                 int i;
6161 
6162                 for (i = 0; i < rvd->vdev_children; i++) {
6163                         vd = rvd->vdev_child[i];
6164                         if (vd->vdev_deflate_ratio != SPA_MINBLOCKSIZE)
6165                                 break;
6166                 }
6167                 if (i == rvd->vdev_children) {
6168                         spa->spa_deflate = TRUE;
6169                         VERIFY(0 == zap_add(spa->spa_meta_objset,
6170                             DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_DEFLATE,
6171                             sizeof (uint64_t), 1, &spa->spa_deflate, tx));
6172                 }
6173         }
6174 
6175         /*
6176          * If anything has changed in this txg, or if someone is waiting
6177          * for this txg to sync (eg, spa_vdev_remove()), push the
6178          * deferred frees from the previous txg.  If not, leave them
6179          * alone so that we don't generate work on an otherwise idle
6180          * system.
6181          */
6182         if (!txg_list_empty(&dp->dp_dirty_datasets, txg) ||
6183             !txg_list_empty(&dp->dp_dirty_dirs, txg) ||
6184             !txg_list_empty(&dp->dp_sync_tasks, txg) ||
6185             ((dsl_scan_active(dp->dp_scan) ||
6186             txg_sync_waiting(dp)) && !spa_shutting_down(spa))) {
6187                 spa_sync_deferred_frees(spa, tx);
6188         }
6189 
6190         /*
6191          * Iterate to convergence.
6192          */
6193         do {
6194                 int pass = ++spa->spa_sync_pass;
6195 
6196                 spa_sync_config_object(spa, tx);
6197                 spa_sync_aux_dev(spa, &spa->spa_spares, tx,
6198                     ZPOOL_CONFIG_SPARES, DMU_POOL_SPARES);
6199                 spa_sync_aux_dev(spa, &spa->spa_l2cache, tx,
6200                     ZPOOL_CONFIG_L2CACHE, DMU_POOL_L2CACHE);
6201                 spa_errlog_sync(spa, txg);
6202                 dsl_pool_sync(dp, txg);
6203 
6204                 if (pass < zfs_sync_pass_deferred_free) {
6205                         spa_sync_frees(spa, free_bpl, tx);
6206                 } else {
6207                         bplist_iterate(free_bpl, bpobj_enqueue_cb,
6208                             &spa->spa_deferred_bpobj, tx);
6209                 }
6210 
6211                 ddt_sync(spa, txg);
6212                 dsl_scan_sync(dp, tx);
6213 
6214                 while (vd = txg_list_remove(&spa->spa_vdev_txg_list, txg))
6215                         vdev_sync(vd, txg);
6216 
6217                 if (pass == 1)
6218                         spa_sync_upgrades(spa, tx);
6219 
6220         } while (dmu_objset_is_dirty(mos, txg));
6221 
6222         /*
6223          * Rewrite the vdev configuration (which includes the uberblock)
6224          * to commit the transaction group.
6225          *
6226          * If there are no dirty vdevs, we sync the uberblock to a few
6227          * random top-level vdevs that are known to be visible in the
6228          * config cache (see spa_vdev_add() for a complete description).
6229          * If there *are* dirty vdevs, sync the uberblock to all vdevs.
6230          */
6231         for (;;) {
6232                 /*
6233                  * We hold SCL_STATE to prevent vdev open/close/etc.
6234                  * while we're attempting to write the vdev labels.
6235                  */
6236                 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
6237 
6238                 if (list_is_empty(&spa->spa_config_dirty_list)) {
6239                         vdev_t *svd[SPA_DVAS_PER_BP];
6240                         int svdcount = 0;
6241                         int children = rvd->vdev_children;
6242                         int c0 = spa_get_random(children);
6243 
6244                         for (int c = 0; c < children; c++) {
6245                                 vd = rvd->vdev_child[(c0 + c) % children];
6246                                 if (vd->vdev_ms_array == 0 || vd->vdev_islog)
6247                                         continue;
6248                                 svd[svdcount++] = vd;
6249                                 if (svdcount == SPA_DVAS_PER_BP)
6250                                         break;
6251                         }
6252                         error = vdev_config_sync(svd, svdcount, txg, B_FALSE);
6253                         if (error != 0)
6254                                 error = vdev_config_sync(svd, svdcount, txg,
6255                                     B_TRUE);
6256                 } else {
6257                         error = vdev_config_sync(rvd->vdev_child,
6258                             rvd->vdev_children, txg, B_FALSE);
6259                         if (error != 0)
6260                                 error = vdev_config_sync(rvd->vdev_child,
6261                                     rvd->vdev_children, txg, B_TRUE);
6262                 }
6263 
6264                 if (error == 0)
6265                         spa->spa_last_synced_guid = rvd->vdev_guid;
6266 
6267                 spa_config_exit(spa, SCL_STATE, FTAG);
6268 
6269                 if (error == 0)
6270                         break;
6271                 zio_suspend(spa, NULL);
6272                 zio_resume_wait(spa);
6273         }
6274         dmu_tx_commit(tx);
6275 
6276         VERIFY(cyclic_reprogram(spa->spa_deadman_cycid, CY_INFINITY));
6277 
6278         /*
6279          * Clear the dirty config list.
6280          */
6281         while ((vd = list_head(&spa->spa_config_dirty_list)) != NULL)
6282                 vdev_config_clean(vd);
6283 
6284         /*
6285          * Now that the new config has synced transactionally,
6286          * let it become visible to the config cache.
6287          */
6288         if (spa->spa_config_syncing != NULL) {
6289                 spa_config_set(spa, spa->spa_config_syncing);
6290                 spa->spa_config_txg = txg;
6291                 spa->spa_config_syncing = NULL;
6292         }
6293 
6294         spa->spa_ubsync = spa->spa_uberblock;
6295 
6296         dsl_pool_sync_done(dp, txg);
6297 
6298         /*
6299          * Update usable space statistics.
6300          */
6301         while (vd = txg_list_remove(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)))
6302                 vdev_sync_done(vd, txg);
6303 
6304         spa_update_dspace(spa);
6305 
6306         /*
6307          * It had better be the case that we didn't dirty anything
6308          * since vdev_config_sync().
6309          */
6310         ASSERT(txg_list_empty(&dp->dp_dirty_datasets, txg));
6311         ASSERT(txg_list_empty(&dp->dp_dirty_dirs, txg));
6312         ASSERT(txg_list_empty(&spa->spa_vdev_txg_list, txg));
6313 
6314         spa->spa_sync_pass = 0;
6315 
6316         spa_config_exit(spa, SCL_CONFIG, FTAG);
6317 
6318         spa_handle_ignored_writes(spa);
6319 
6320         /*
6321          * If any async tasks have been requested, kick them off.
6322          */
6323         spa_async_dispatch(spa);
6324 }
6325 
6326 /*
6327  * Sync all pools.  We don't want to hold the namespace lock across these
6328  * operations, so we take a reference on the spa_t and drop the lock during the
6329  * sync.
6330  */
6331 void
6332 spa_sync_allpools(void)
6333 {
6334         spa_t *spa = NULL;
6335         mutex_enter(&spa_namespace_lock);
6336         while ((spa = spa_next(spa)) != NULL) {
6337                 if (spa_state(spa) != POOL_STATE_ACTIVE ||
6338                     !spa_writeable(spa) || spa_suspended(spa))
6339                         continue;
6340                 spa_open_ref(spa, FTAG);
6341                 mutex_exit(&spa_namespace_lock);
6342                 txg_wait_synced(spa_get_dsl(spa), 0);
6343                 mutex_enter(&spa_namespace_lock);
6344                 spa_close(spa, FTAG);
6345         }
6346         mutex_exit(&spa_namespace_lock);
6347 }
6348 
6349 /*
6350  * ==========================================================================
6351  * Miscellaneous routines
6352  * ==========================================================================
6353  */
6354 
6355 /*
6356  * Remove all pools in the system.
6357  */
6358 void
6359 spa_evict_all(void)
6360 {
6361         spa_t *spa;
6362 
6363         /*
6364          * Remove all cached state.  All pools should be closed now,
6365          * so every spa in the AVL tree should be unreferenced.
6366          */
6367         mutex_enter(&spa_namespace_lock);
6368         while ((spa = spa_next(NULL)) != NULL) {
6369                 /*
6370                  * Stop async tasks.  The async thread may need to detach
6371                  * a device that's been replaced, which requires grabbing
6372                  * spa_namespace_lock, so we must drop it here.
6373                  */
6374                 spa_open_ref(spa, FTAG);
6375                 mutex_exit(&spa_namespace_lock);
6376                 spa_async_suspend(spa);
6377                 mutex_enter(&spa_namespace_lock);
6378                 spa_close(spa, FTAG);
6379 
6380                 if (spa->spa_state != POOL_STATE_UNINITIALIZED) {
6381                         spa_unload(spa);
6382                         spa_deactivate(spa);
6383                 }
6384                 spa_remove(spa);
6385         }
6386         mutex_exit(&spa_namespace_lock);
6387 }
6388 
6389 vdev_t *
6390 spa_lookup_by_guid(spa_t *spa, uint64_t guid, boolean_t aux)
6391 {
6392         vdev_t *vd;
6393         int i;
6394 
6395         if ((vd = vdev_lookup_by_guid(spa->spa_root_vdev, guid)) != NULL)
6396                 return (vd);
6397 
6398         if (aux) {
6399                 for (i = 0; i < spa->spa_l2cache.sav_count; i++) {
6400                         vd = spa->spa_l2cache.sav_vdevs[i];
6401                         if (vd->vdev_guid == guid)
6402                                 return (vd);
6403                 }
6404 
6405                 for (i = 0; i < spa->spa_spares.sav_count; i++) {
6406                         vd = spa->spa_spares.sav_vdevs[i];
6407                         if (vd->vdev_guid == guid)
6408                                 return (vd);
6409                 }
6410         }
6411 
6412         return (NULL);
6413 }
6414 
6415 void
6416 spa_upgrade(spa_t *spa, uint64_t version)
6417 {
6418         ASSERT(spa_writeable(spa));
6419 
6420         spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
6421 
6422         /*
6423          * This should only be called for a non-faulted pool, and since a
6424          * future version would result in an unopenable pool, this shouldn't be
6425          * possible.
6426          */
6427         ASSERT(SPA_VERSION_IS_SUPPORTED(spa->spa_uberblock.ub_version));
6428         ASSERT(version >= spa->spa_uberblock.ub_version);
6429 
6430         spa->spa_uberblock.ub_version = version;
6431         vdev_config_dirty(spa->spa_root_vdev);
6432 
6433         spa_config_exit(spa, SCL_ALL, FTAG);
6434 
6435         txg_wait_synced(spa_get_dsl(spa), 0);
6436 }
6437 
6438 boolean_t
6439 spa_has_spare(spa_t *spa, uint64_t guid)
6440 {
6441         int i;
6442         uint64_t spareguid;
6443         spa_aux_vdev_t *sav = &spa->spa_spares;
6444 
6445         for (i = 0; i < sav->sav_count; i++)
6446                 if (sav->sav_vdevs[i]->vdev_guid == guid)
6447                         return (B_TRUE);
6448 
6449         for (i = 0; i < sav->sav_npending; i++) {
6450                 if (nvlist_lookup_uint64(sav->sav_pending[i], ZPOOL_CONFIG_GUID,
6451                     &spareguid) == 0 && spareguid == guid)
6452                         return (B_TRUE);
6453         }
6454 
6455         return (B_FALSE);
6456 }
6457 
6458 /*
6459  * Check if a pool has an active shared spare device.
6460  * Note: reference count of an active spare is 2, as a spare and as a replace
6461  */
6462 static boolean_t
6463 spa_has_active_shared_spare(spa_t *spa)
6464 {
6465         int i, refcnt;
6466         uint64_t pool;
6467         spa_aux_vdev_t *sav = &spa->spa_spares;
6468 
6469         for (i = 0; i < sav->sav_count; i++) {
6470                 if (spa_spare_exists(sav->sav_vdevs[i]->vdev_guid, &pool,
6471                     &refcnt) && pool != 0ULL && pool == spa_guid(spa) &&
6472                     refcnt > 2)
6473                         return (B_TRUE);
6474         }
6475 
6476         return (B_FALSE);
6477 }
6478 
6479 /*
6480  * Post a sysevent corresponding to the given event.  The 'name' must be one of
6481  * the event definitions in sys/sysevent/eventdefs.h.  The payload will be
6482  * filled in from the spa and (optionally) the vdev.  This doesn't do anything
6483  * in the userland libzpool, as we don't want consumers to misinterpret ztest
6484  * or zdb as real changes.
6485  */
6486 void
6487 spa_event_notify(spa_t *spa, vdev_t *vd, const char *name)
6488 {
6489 #ifdef _KERNEL
6490         sysevent_t              *ev;
6491         sysevent_attr_list_t    *attr = NULL;
6492         sysevent_value_t        value;
6493         sysevent_id_t           eid;
6494 
6495         ev = sysevent_alloc(EC_ZFS, (char *)name, SUNW_KERN_PUB "zfs",
6496             SE_SLEEP);
6497 
6498         value.value_type = SE_DATA_TYPE_STRING;
6499         value.value.sv_string = spa_name(spa);
6500         if (sysevent_add_attr(&attr, ZFS_EV_POOL_NAME, &value, SE_SLEEP) != 0)
6501                 goto done;
6502 
6503         value.value_type = SE_DATA_TYPE_UINT64;
6504         value.value.sv_uint64 = spa_guid(spa);
6505         if (sysevent_add_attr(&attr, ZFS_EV_POOL_GUID, &value, SE_SLEEP) != 0)
6506                 goto done;
6507 
6508         if (vd) {
6509                 value.value_type = SE_DATA_TYPE_UINT64;
6510                 value.value.sv_uint64 = vd->vdev_guid;
6511                 if (sysevent_add_attr(&attr, ZFS_EV_VDEV_GUID, &value,
6512                     SE_SLEEP) != 0)
6513                         goto done;
6514 
6515                 if (vd->vdev_path) {
6516                         value.value_type = SE_DATA_TYPE_STRING;
6517                         value.value.sv_string = vd->vdev_path;
6518                         if (sysevent_add_attr(&attr, ZFS_EV_VDEV_PATH,
6519                             &value, SE_SLEEP) != 0)
6520                                 goto done;
6521                 }
6522         }
6523 
6524         if (sysevent_attach_attributes(ev, attr) != 0)
6525                 goto done;
6526         attr = NULL;
6527 
6528         (void) log_sysevent(ev, SE_SLEEP, &eid);
6529 
6530 done:
6531         if (attr)
6532                 sysevent_free_attr(attr);
6533         sysevent_free(ev);
6534 #endif
6535 }