xref: /titanic_44/usr/src/uts/common/fs/zfs/spa.c (revision 34f9b3eef6fdadbda0a846aa4d68691ac40eace5)
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 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * This file contains all the routines used when modifying on-disk SPA state.
29  * This includes opening, importing, destroying, exporting a pool, and syncing a
30  * pool.
31  */
32 
33 #include <sys/zfs_context.h>
34 #include <sys/fm/fs/zfs.h>
35 #include <sys/spa_impl.h>
36 #include <sys/zio.h>
37 #include <sys/zio_checksum.h>
38 #include <sys/zio_compress.h>
39 #include <sys/dmu.h>
40 #include <sys/dmu_tx.h>
41 #include <sys/zap.h>
42 #include <sys/zil.h>
43 #include <sys/vdev_impl.h>
44 #include <sys/metaslab.h>
45 #include <sys/metaslab_impl.h>
46 #include <sys/uberblock_impl.h>
47 #include <sys/txg.h>
48 #include <sys/avl.h>
49 #include <sys/dmu_traverse.h>
50 #include <sys/dmu_objset.h>
51 #include <sys/unique.h>
52 #include <sys/dsl_pool.h>
53 #include <sys/dsl_dataset.h>
54 #include <sys/dsl_dir.h>
55 #include <sys/dsl_prop.h>
56 #include <sys/dsl_synctask.h>
57 #include <sys/fs/zfs.h>
58 #include <sys/arc.h>
59 #include <sys/callb.h>
60 #include <sys/systeminfo.h>
61 #include <sys/sunddi.h>
62 #include <sys/spa_boot.h>
63 #include <sys/zfs_ioctl.h>
64 
65 #ifdef	_KERNEL
66 #include <sys/zone.h>
67 #include <sys/bootprops.h>
68 #endif	/* _KERNEL */
69 
70 #include "zfs_prop.h"
71 #include "zfs_comutil.h"
72 
73 enum zti_modes {
74 	zti_mode_fixed,			/* value is # of threads (min 1) */
75 	zti_mode_online_percent,	/* value is % of online CPUs */
76 	zti_mode_tune,			/* fill from zio_taskq_tune_* */
77 	zti_nmodes
78 };
79 
80 #define	ZTI_THREAD_FIX(n)	{ zti_mode_fixed, (n) }
81 #define	ZTI_THREAD_PCT(n)	{ zti_mode_online_percent, (n) }
82 #define	ZTI_THREAD_TUNE		{ zti_mode_tune, 0 }
83 
84 #define	ZTI_THREAD_ONE		ZTI_THREAD_FIX(1)
85 
86 typedef struct zio_taskq_info {
87 	const char *zti_name;
88 	struct {
89 		enum zti_modes zti_mode;
90 		uint_t zti_value;
91 	} zti_nthreads[ZIO_TASKQ_TYPES];
92 } zio_taskq_info_t;
93 
94 static const char *const zio_taskq_types[ZIO_TASKQ_TYPES] = {
95 				"issue",		"intr"
96 };
97 
98 const zio_taskq_info_t zio_taskqs[ZIO_TYPES] = {
99 	/*			ISSUE			INTR		*/
100 	{ "spa_zio_null",	{ ZTI_THREAD_ONE,	ZTI_THREAD_ONE } },
101 	{ "spa_zio_read",	{ ZTI_THREAD_FIX(8),	ZTI_THREAD_TUNE } },
102 	{ "spa_zio_write",	{ ZTI_THREAD_TUNE,	ZTI_THREAD_FIX(8) } },
103 	{ "spa_zio_free",	{ ZTI_THREAD_ONE,	ZTI_THREAD_ONE } },
104 	{ "spa_zio_claim",	{ ZTI_THREAD_ONE,	ZTI_THREAD_ONE } },
105 	{ "spa_zio_ioctl",	{ ZTI_THREAD_ONE,	ZTI_THREAD_ONE } },
106 };
107 
108 enum zti_modes zio_taskq_tune_mode = zti_mode_online_percent;
109 uint_t zio_taskq_tune_value = 80;	/* #threads = 80% of # online CPUs */
110 
111 static void spa_sync_props(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx);
112 static boolean_t spa_has_active_shared_spare(spa_t *spa);
113 
114 /*
115  * ==========================================================================
116  * SPA properties routines
117  * ==========================================================================
118  */
119 
120 /*
121  * Add a (source=src, propname=propval) list to an nvlist.
122  */
123 static void
124 spa_prop_add_list(nvlist_t *nvl, zpool_prop_t prop, char *strval,
125     uint64_t intval, zprop_source_t src)
126 {
127 	const char *propname = zpool_prop_to_name(prop);
128 	nvlist_t *propval;
129 
130 	VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
131 	VERIFY(nvlist_add_uint64(propval, ZPROP_SOURCE, src) == 0);
132 
133 	if (strval != NULL)
134 		VERIFY(nvlist_add_string(propval, ZPROP_VALUE, strval) == 0);
135 	else
136 		VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, intval) == 0);
137 
138 	VERIFY(nvlist_add_nvlist(nvl, propname, propval) == 0);
139 	nvlist_free(propval);
140 }
141 
142 /*
143  * Get property values from the spa configuration.
144  */
145 static void
146 spa_prop_get_config(spa_t *spa, nvlist_t **nvp)
147 {
148 	uint64_t size;
149 	uint64_t used;
150 	uint64_t cap, version;
151 	zprop_source_t src = ZPROP_SRC_NONE;
152 	spa_config_dirent_t *dp;
153 
154 	ASSERT(MUTEX_HELD(&spa->spa_props_lock));
155 
156 	if (spa->spa_root_vdev != NULL) {
157 		size = spa_get_space(spa);
158 		used = spa_get_alloc(spa);
159 		spa_prop_add_list(*nvp, ZPOOL_PROP_NAME, spa_name(spa), 0, src);
160 		spa_prop_add_list(*nvp, ZPOOL_PROP_SIZE, NULL, size, src);
161 		spa_prop_add_list(*nvp, ZPOOL_PROP_USED, NULL, used, src);
162 		spa_prop_add_list(*nvp, ZPOOL_PROP_AVAILABLE, NULL,
163 		    size - used, src);
164 
165 		cap = (size == 0) ? 0 : (used * 100 / size);
166 		spa_prop_add_list(*nvp, ZPOOL_PROP_CAPACITY, NULL, cap, src);
167 
168 		spa_prop_add_list(*nvp, ZPOOL_PROP_HEALTH, NULL,
169 		    spa->spa_root_vdev->vdev_state, src);
170 
171 		version = spa_version(spa);
172 		if (version == zpool_prop_default_numeric(ZPOOL_PROP_VERSION))
173 			src = ZPROP_SRC_DEFAULT;
174 		else
175 			src = ZPROP_SRC_LOCAL;
176 		spa_prop_add_list(*nvp, ZPOOL_PROP_VERSION, NULL, version, src);
177 	}
178 
179 	spa_prop_add_list(*nvp, ZPOOL_PROP_GUID, NULL, spa_guid(spa), src);
180 
181 	if (spa->spa_root != NULL)
182 		spa_prop_add_list(*nvp, ZPOOL_PROP_ALTROOT, spa->spa_root,
183 		    0, ZPROP_SRC_LOCAL);
184 
185 	if ((dp = list_head(&spa->spa_config_list)) != NULL) {
186 		if (dp->scd_path == NULL) {
187 			spa_prop_add_list(*nvp, ZPOOL_PROP_CACHEFILE,
188 			    "none", 0, ZPROP_SRC_LOCAL);
189 		} else if (strcmp(dp->scd_path, spa_config_path) != 0) {
190 			spa_prop_add_list(*nvp, ZPOOL_PROP_CACHEFILE,
191 			    dp->scd_path, 0, ZPROP_SRC_LOCAL);
192 		}
193 	}
194 }
195 
196 /*
197  * Get zpool property values.
198  */
199 int
200 spa_prop_get(spa_t *spa, nvlist_t **nvp)
201 {
202 	zap_cursor_t zc;
203 	zap_attribute_t za;
204 	objset_t *mos = spa->spa_meta_objset;
205 	int err;
206 
207 	VERIFY(nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
208 
209 	mutex_enter(&spa->spa_props_lock);
210 
211 	/*
212 	 * Get properties from the spa config.
213 	 */
214 	spa_prop_get_config(spa, nvp);
215 
216 	/* If no pool property object, no more prop to get. */
217 	if (spa->spa_pool_props_object == 0) {
218 		mutex_exit(&spa->spa_props_lock);
219 		return (0);
220 	}
221 
222 	/*
223 	 * Get properties from the MOS pool property object.
224 	 */
225 	for (zap_cursor_init(&zc, mos, spa->spa_pool_props_object);
226 	    (err = zap_cursor_retrieve(&zc, &za)) == 0;
227 	    zap_cursor_advance(&zc)) {
228 		uint64_t intval = 0;
229 		char *strval = NULL;
230 		zprop_source_t src = ZPROP_SRC_DEFAULT;
231 		zpool_prop_t prop;
232 
233 		if ((prop = zpool_name_to_prop(za.za_name)) == ZPROP_INVAL)
234 			continue;
235 
236 		switch (za.za_integer_length) {
237 		case 8:
238 			/* integer property */
239 			if (za.za_first_integer !=
240 			    zpool_prop_default_numeric(prop))
241 				src = ZPROP_SRC_LOCAL;
242 
243 			if (prop == ZPOOL_PROP_BOOTFS) {
244 				dsl_pool_t *dp;
245 				dsl_dataset_t *ds = NULL;
246 
247 				dp = spa_get_dsl(spa);
248 				rw_enter(&dp->dp_config_rwlock, RW_READER);
249 				if (err = dsl_dataset_hold_obj(dp,
250 				    za.za_first_integer, FTAG, &ds)) {
251 					rw_exit(&dp->dp_config_rwlock);
252 					break;
253 				}
254 
255 				strval = kmem_alloc(
256 				    MAXNAMELEN + strlen(MOS_DIR_NAME) + 1,
257 				    KM_SLEEP);
258 				dsl_dataset_name(ds, strval);
259 				dsl_dataset_rele(ds, FTAG);
260 				rw_exit(&dp->dp_config_rwlock);
261 			} else {
262 				strval = NULL;
263 				intval = za.za_first_integer;
264 			}
265 
266 			spa_prop_add_list(*nvp, prop, strval, intval, src);
267 
268 			if (strval != NULL)
269 				kmem_free(strval,
270 				    MAXNAMELEN + strlen(MOS_DIR_NAME) + 1);
271 
272 			break;
273 
274 		case 1:
275 			/* string property */
276 			strval = kmem_alloc(za.za_num_integers, KM_SLEEP);
277 			err = zap_lookup(mos, spa->spa_pool_props_object,
278 			    za.za_name, 1, za.za_num_integers, strval);
279 			if (err) {
280 				kmem_free(strval, za.za_num_integers);
281 				break;
282 			}
283 			spa_prop_add_list(*nvp, prop, strval, 0, src);
284 			kmem_free(strval, za.za_num_integers);
285 			break;
286 
287 		default:
288 			break;
289 		}
290 	}
291 	zap_cursor_fini(&zc);
292 	mutex_exit(&spa->spa_props_lock);
293 out:
294 	if (err && err != ENOENT) {
295 		nvlist_free(*nvp);
296 		*nvp = NULL;
297 		return (err);
298 	}
299 
300 	return (0);
301 }
302 
303 /*
304  * Validate the given pool properties nvlist and modify the list
305  * for the property values to be set.
306  */
307 static int
308 spa_prop_validate(spa_t *spa, nvlist_t *props)
309 {
310 	nvpair_t *elem;
311 	int error = 0, reset_bootfs = 0;
312 	uint64_t objnum;
313 
314 	elem = NULL;
315 	while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
316 		zpool_prop_t prop;
317 		char *propname, *strval;
318 		uint64_t intval;
319 		objset_t *os;
320 		char *slash;
321 
322 		propname = nvpair_name(elem);
323 
324 		if ((prop = zpool_name_to_prop(propname)) == ZPROP_INVAL)
325 			return (EINVAL);
326 
327 		switch (prop) {
328 		case ZPOOL_PROP_VERSION:
329 			error = nvpair_value_uint64(elem, &intval);
330 			if (!error &&
331 			    (intval < spa_version(spa) || intval > SPA_VERSION))
332 				error = EINVAL;
333 			break;
334 
335 		case ZPOOL_PROP_DELEGATION:
336 		case ZPOOL_PROP_AUTOREPLACE:
337 		case ZPOOL_PROP_LISTSNAPS:
338 		case ZPOOL_PROP_AUTOEXPAND:
339 			error = nvpair_value_uint64(elem, &intval);
340 			if (!error && intval > 1)
341 				error = EINVAL;
342 			break;
343 
344 		case ZPOOL_PROP_BOOTFS:
345 			/*
346 			 * If the pool version is less than SPA_VERSION_BOOTFS,
347 			 * or the pool is still being created (version == 0),
348 			 * the bootfs property cannot be set.
349 			 */
350 			if (spa_version(spa) < SPA_VERSION_BOOTFS) {
351 				error = ENOTSUP;
352 				break;
353 			}
354 
355 			/*
356 			 * Make sure the vdev config is bootable
357 			 */
358 			if (!vdev_is_bootable(spa->spa_root_vdev)) {
359 				error = ENOTSUP;
360 				break;
361 			}
362 
363 			reset_bootfs = 1;
364 
365 			error = nvpair_value_string(elem, &strval);
366 
367 			if (!error) {
368 				uint64_t compress;
369 
370 				if (strval == NULL || strval[0] == '\0') {
371 					objnum = zpool_prop_default_numeric(
372 					    ZPOOL_PROP_BOOTFS);
373 					break;
374 				}
375 
376 				if (error = dmu_objset_hold(strval, FTAG, &os))
377 					break;
378 
379 				/* Must be ZPL and not gzip compressed. */
380 
381 				if (dmu_objset_type(os) != DMU_OST_ZFS) {
382 					error = ENOTSUP;
383 				} else if ((error = dsl_prop_get_integer(strval,
384 				    zfs_prop_to_name(ZFS_PROP_COMPRESSION),
385 				    &compress, NULL)) == 0 &&
386 				    !BOOTFS_COMPRESS_VALID(compress)) {
387 					error = ENOTSUP;
388 				} else {
389 					objnum = dmu_objset_id(os);
390 				}
391 				dmu_objset_rele(os, FTAG);
392 			}
393 			break;
394 
395 		case ZPOOL_PROP_FAILUREMODE:
396 			error = nvpair_value_uint64(elem, &intval);
397 			if (!error && (intval < ZIO_FAILURE_MODE_WAIT ||
398 			    intval > ZIO_FAILURE_MODE_PANIC))
399 				error = EINVAL;
400 
401 			/*
402 			 * This is a special case which only occurs when
403 			 * the pool has completely failed. This allows
404 			 * the user to change the in-core failmode property
405 			 * without syncing it out to disk (I/Os might
406 			 * currently be blocked). We do this by returning
407 			 * EIO to the caller (spa_prop_set) to trick it
408 			 * into thinking we encountered a property validation
409 			 * error.
410 			 */
411 			if (!error && spa_suspended(spa)) {
412 				spa->spa_failmode = intval;
413 				error = EIO;
414 			}
415 			break;
416 
417 		case ZPOOL_PROP_CACHEFILE:
418 			if ((error = nvpair_value_string(elem, &strval)) != 0)
419 				break;
420 
421 			if (strval[0] == '\0')
422 				break;
423 
424 			if (strcmp(strval, "none") == 0)
425 				break;
426 
427 			if (strval[0] != '/') {
428 				error = EINVAL;
429 				break;
430 			}
431 
432 			slash = strrchr(strval, '/');
433 			ASSERT(slash != NULL);
434 
435 			if (slash[1] == '\0' || strcmp(slash, "/.") == 0 ||
436 			    strcmp(slash, "/..") == 0)
437 				error = EINVAL;
438 			break;
439 		}
440 
441 		if (error)
442 			break;
443 	}
444 
445 	if (!error && reset_bootfs) {
446 		error = nvlist_remove(props,
447 		    zpool_prop_to_name(ZPOOL_PROP_BOOTFS), DATA_TYPE_STRING);
448 
449 		if (!error) {
450 			error = nvlist_add_uint64(props,
451 			    zpool_prop_to_name(ZPOOL_PROP_BOOTFS), objnum);
452 		}
453 	}
454 
455 	return (error);
456 }
457 
458 void
459 spa_configfile_set(spa_t *spa, nvlist_t *nvp, boolean_t need_sync)
460 {
461 	char *cachefile;
462 	spa_config_dirent_t *dp;
463 
464 	if (nvlist_lookup_string(nvp, zpool_prop_to_name(ZPOOL_PROP_CACHEFILE),
465 	    &cachefile) != 0)
466 		return;
467 
468 	dp = kmem_alloc(sizeof (spa_config_dirent_t),
469 	    KM_SLEEP);
470 
471 	if (cachefile[0] == '\0')
472 		dp->scd_path = spa_strdup(spa_config_path);
473 	else if (strcmp(cachefile, "none") == 0)
474 		dp->scd_path = NULL;
475 	else
476 		dp->scd_path = spa_strdup(cachefile);
477 
478 	list_insert_head(&spa->spa_config_list, dp);
479 	if (need_sync)
480 		spa_async_request(spa, SPA_ASYNC_CONFIG_UPDATE);
481 }
482 
483 int
484 spa_prop_set(spa_t *spa, nvlist_t *nvp)
485 {
486 	int error;
487 	nvpair_t *elem;
488 	boolean_t need_sync = B_FALSE;
489 	zpool_prop_t prop;
490 
491 	if ((error = spa_prop_validate(spa, nvp)) != 0)
492 		return (error);
493 
494 	elem = NULL;
495 	while ((elem = nvlist_next_nvpair(nvp, elem)) != NULL) {
496 		if ((prop = zpool_name_to_prop(
497 		    nvpair_name(elem))) == ZPROP_INVAL)
498 			return (EINVAL);
499 
500 		if (prop == ZPOOL_PROP_CACHEFILE || prop == ZPOOL_PROP_ALTROOT)
501 			continue;
502 
503 		need_sync = B_TRUE;
504 		break;
505 	}
506 
507 	if (need_sync)
508 		return (dsl_sync_task_do(spa_get_dsl(spa), NULL, spa_sync_props,
509 		    spa, nvp, 3));
510 	else
511 		return (0);
512 }
513 
514 /*
515  * If the bootfs property value is dsobj, clear it.
516  */
517 void
518 spa_prop_clear_bootfs(spa_t *spa, uint64_t dsobj, dmu_tx_t *tx)
519 {
520 	if (spa->spa_bootfs == dsobj && spa->spa_pool_props_object != 0) {
521 		VERIFY(zap_remove(spa->spa_meta_objset,
522 		    spa->spa_pool_props_object,
523 		    zpool_prop_to_name(ZPOOL_PROP_BOOTFS), tx) == 0);
524 		spa->spa_bootfs = 0;
525 	}
526 }
527 
528 /*
529  * ==========================================================================
530  * SPA state manipulation (open/create/destroy/import/export)
531  * ==========================================================================
532  */
533 
534 static int
535 spa_error_entry_compare(const void *a, const void *b)
536 {
537 	spa_error_entry_t *sa = (spa_error_entry_t *)a;
538 	spa_error_entry_t *sb = (spa_error_entry_t *)b;
539 	int ret;
540 
541 	ret = bcmp(&sa->se_bookmark, &sb->se_bookmark,
542 	    sizeof (zbookmark_t));
543 
544 	if (ret < 0)
545 		return (-1);
546 	else if (ret > 0)
547 		return (1);
548 	else
549 		return (0);
550 }
551 
552 /*
553  * Utility function which retrieves copies of the current logs and
554  * re-initializes them in the process.
555  */
556 void
557 spa_get_errlists(spa_t *spa, avl_tree_t *last, avl_tree_t *scrub)
558 {
559 	ASSERT(MUTEX_HELD(&spa->spa_errlist_lock));
560 
561 	bcopy(&spa->spa_errlist_last, last, sizeof (avl_tree_t));
562 	bcopy(&spa->spa_errlist_scrub, scrub, sizeof (avl_tree_t));
563 
564 	avl_create(&spa->spa_errlist_scrub,
565 	    spa_error_entry_compare, sizeof (spa_error_entry_t),
566 	    offsetof(spa_error_entry_t, se_avl));
567 	avl_create(&spa->spa_errlist_last,
568 	    spa_error_entry_compare, sizeof (spa_error_entry_t),
569 	    offsetof(spa_error_entry_t, se_avl));
570 }
571 
572 /*
573  * Activate an uninitialized pool.
574  */
575 static void
576 spa_activate(spa_t *spa, int mode)
577 {
578 	ASSERT(spa->spa_state == POOL_STATE_UNINITIALIZED);
579 
580 	spa->spa_state = POOL_STATE_ACTIVE;
581 	spa->spa_mode = mode;
582 
583 	spa->spa_normal_class = metaslab_class_create(spa, zfs_metaslab_ops);
584 	spa->spa_log_class = metaslab_class_create(spa, zfs_metaslab_ops);
585 
586 	for (int t = 0; t < ZIO_TYPES; t++) {
587 		const zio_taskq_info_t *ztip = &zio_taskqs[t];
588 		for (int q = 0; q < ZIO_TASKQ_TYPES; q++) {
589 			enum zti_modes mode = ztip->zti_nthreads[q].zti_mode;
590 			uint_t value = ztip->zti_nthreads[q].zti_value;
591 			char name[32];
592 
593 			(void) snprintf(name, sizeof (name),
594 			    "%s_%s", ztip->zti_name, zio_taskq_types[q]);
595 
596 			if (mode == zti_mode_tune) {
597 				mode = zio_taskq_tune_mode;
598 				value = zio_taskq_tune_value;
599 				if (mode == zti_mode_tune)
600 					mode = zti_mode_online_percent;
601 			}
602 
603 			switch (mode) {
604 			case zti_mode_fixed:
605 				ASSERT3U(value, >=, 1);
606 				value = MAX(value, 1);
607 
608 				spa->spa_zio_taskq[t][q] = taskq_create(name,
609 				    value, maxclsyspri, 50, INT_MAX,
610 				    TASKQ_PREPOPULATE);
611 				break;
612 
613 			case zti_mode_online_percent:
614 				spa->spa_zio_taskq[t][q] = taskq_create(name,
615 				    value, maxclsyspri, 50, INT_MAX,
616 				    TASKQ_PREPOPULATE | TASKQ_THREADS_CPU_PCT);
617 				break;
618 
619 			case zti_mode_tune:
620 			default:
621 				panic("unrecognized mode for "
622 				    "zio_taskqs[%u]->zti_nthreads[%u] (%u:%u) "
623 				    "in spa_activate()",
624 				    t, q, mode, value);
625 				break;
626 			}
627 		}
628 	}
629 
630 	list_create(&spa->spa_config_dirty_list, sizeof (vdev_t),
631 	    offsetof(vdev_t, vdev_config_dirty_node));
632 	list_create(&spa->spa_state_dirty_list, sizeof (vdev_t),
633 	    offsetof(vdev_t, vdev_state_dirty_node));
634 
635 	txg_list_create(&spa->spa_vdev_txg_list,
636 	    offsetof(struct vdev, vdev_txg_node));
637 
638 	avl_create(&spa->spa_errlist_scrub,
639 	    spa_error_entry_compare, sizeof (spa_error_entry_t),
640 	    offsetof(spa_error_entry_t, se_avl));
641 	avl_create(&spa->spa_errlist_last,
642 	    spa_error_entry_compare, sizeof (spa_error_entry_t),
643 	    offsetof(spa_error_entry_t, se_avl));
644 }
645 
646 /*
647  * Opposite of spa_activate().
648  */
649 static void
650 spa_deactivate(spa_t *spa)
651 {
652 	ASSERT(spa->spa_sync_on == B_FALSE);
653 	ASSERT(spa->spa_dsl_pool == NULL);
654 	ASSERT(spa->spa_root_vdev == NULL);
655 	ASSERT(spa->spa_async_zio_root == NULL);
656 	ASSERT(spa->spa_state != POOL_STATE_UNINITIALIZED);
657 
658 	txg_list_destroy(&spa->spa_vdev_txg_list);
659 
660 	list_destroy(&spa->spa_config_dirty_list);
661 	list_destroy(&spa->spa_state_dirty_list);
662 
663 	for (int t = 0; t < ZIO_TYPES; t++) {
664 		for (int q = 0; q < ZIO_TASKQ_TYPES; q++) {
665 			taskq_destroy(spa->spa_zio_taskq[t][q]);
666 			spa->spa_zio_taskq[t][q] = NULL;
667 		}
668 	}
669 
670 	metaslab_class_destroy(spa->spa_normal_class);
671 	spa->spa_normal_class = NULL;
672 
673 	metaslab_class_destroy(spa->spa_log_class);
674 	spa->spa_log_class = NULL;
675 
676 	/*
677 	 * If this was part of an import or the open otherwise failed, we may
678 	 * still have errors left in the queues.  Empty them just in case.
679 	 */
680 	spa_errlog_drain(spa);
681 
682 	avl_destroy(&spa->spa_errlist_scrub);
683 	avl_destroy(&spa->spa_errlist_last);
684 
685 	spa->spa_state = POOL_STATE_UNINITIALIZED;
686 }
687 
688 /*
689  * Verify a pool configuration, and construct the vdev tree appropriately.  This
690  * will create all the necessary vdevs in the appropriate layout, with each vdev
691  * in the CLOSED state.  This will prep the pool before open/creation/import.
692  * All vdev validation is done by the vdev_alloc() routine.
693  */
694 static int
695 spa_config_parse(spa_t *spa, vdev_t **vdp, nvlist_t *nv, vdev_t *parent,
696     uint_t id, int atype)
697 {
698 	nvlist_t **child;
699 	uint_t children;
700 	int error;
701 
702 	if ((error = vdev_alloc(spa, vdp, nv, parent, id, atype)) != 0)
703 		return (error);
704 
705 	if ((*vdp)->vdev_ops->vdev_op_leaf)
706 		return (0);
707 
708 	error = nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
709 	    &child, &children);
710 
711 	if (error == ENOENT)
712 		return (0);
713 
714 	if (error) {
715 		vdev_free(*vdp);
716 		*vdp = NULL;
717 		return (EINVAL);
718 	}
719 
720 	for (int c = 0; c < children; c++) {
721 		vdev_t *vd;
722 		if ((error = spa_config_parse(spa, &vd, child[c], *vdp, c,
723 		    atype)) != 0) {
724 			vdev_free(*vdp);
725 			*vdp = NULL;
726 			return (error);
727 		}
728 	}
729 
730 	ASSERT(*vdp != NULL);
731 
732 	return (0);
733 }
734 
735 /*
736  * Opposite of spa_load().
737  */
738 static void
739 spa_unload(spa_t *spa)
740 {
741 	int i;
742 
743 	ASSERT(MUTEX_HELD(&spa_namespace_lock));
744 
745 	/*
746 	 * Stop async tasks.
747 	 */
748 	spa_async_suspend(spa);
749 
750 	/*
751 	 * Stop syncing.
752 	 */
753 	if (spa->spa_sync_on) {
754 		txg_sync_stop(spa->spa_dsl_pool);
755 		spa->spa_sync_on = B_FALSE;
756 	}
757 
758 	/*
759 	 * Wait for any outstanding async I/O to complete.
760 	 */
761 	if (spa->spa_async_zio_root != NULL) {
762 		(void) zio_wait(spa->spa_async_zio_root);
763 		spa->spa_async_zio_root = NULL;
764 	}
765 
766 	/*
767 	 * Close the dsl pool.
768 	 */
769 	if (spa->spa_dsl_pool) {
770 		dsl_pool_close(spa->spa_dsl_pool);
771 		spa->spa_dsl_pool = NULL;
772 	}
773 
774 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
775 
776 	/*
777 	 * Drop and purge level 2 cache
778 	 */
779 	spa_l2cache_drop(spa);
780 
781 	/*
782 	 * Close all vdevs.
783 	 */
784 	if (spa->spa_root_vdev)
785 		vdev_free(spa->spa_root_vdev);
786 	ASSERT(spa->spa_root_vdev == NULL);
787 
788 	for (i = 0; i < spa->spa_spares.sav_count; i++)
789 		vdev_free(spa->spa_spares.sav_vdevs[i]);
790 	if (spa->spa_spares.sav_vdevs) {
791 		kmem_free(spa->spa_spares.sav_vdevs,
792 		    spa->spa_spares.sav_count * sizeof (void *));
793 		spa->spa_spares.sav_vdevs = NULL;
794 	}
795 	if (spa->spa_spares.sav_config) {
796 		nvlist_free(spa->spa_spares.sav_config);
797 		spa->spa_spares.sav_config = NULL;
798 	}
799 	spa->spa_spares.sav_count = 0;
800 
801 	for (i = 0; i < spa->spa_l2cache.sav_count; i++)
802 		vdev_free(spa->spa_l2cache.sav_vdevs[i]);
803 	if (spa->spa_l2cache.sav_vdevs) {
804 		kmem_free(spa->spa_l2cache.sav_vdevs,
805 		    spa->spa_l2cache.sav_count * sizeof (void *));
806 		spa->spa_l2cache.sav_vdevs = NULL;
807 	}
808 	if (spa->spa_l2cache.sav_config) {
809 		nvlist_free(spa->spa_l2cache.sav_config);
810 		spa->spa_l2cache.sav_config = NULL;
811 	}
812 	spa->spa_l2cache.sav_count = 0;
813 
814 	spa->spa_async_suspended = 0;
815 
816 	spa_config_exit(spa, SCL_ALL, FTAG);
817 }
818 
819 /*
820  * Load (or re-load) the current list of vdevs describing the active spares for
821  * this pool.  When this is called, we have some form of basic information in
822  * 'spa_spares.sav_config'.  We parse this into vdevs, try to open them, and
823  * then re-generate a more complete list including status information.
824  */
825 static void
826 spa_load_spares(spa_t *spa)
827 {
828 	nvlist_t **spares;
829 	uint_t nspares;
830 	int i;
831 	vdev_t *vd, *tvd;
832 
833 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
834 
835 	/*
836 	 * First, close and free any existing spare vdevs.
837 	 */
838 	for (i = 0; i < spa->spa_spares.sav_count; i++) {
839 		vd = spa->spa_spares.sav_vdevs[i];
840 
841 		/* Undo the call to spa_activate() below */
842 		if ((tvd = spa_lookup_by_guid(spa, vd->vdev_guid,
843 		    B_FALSE)) != NULL && tvd->vdev_isspare)
844 			spa_spare_remove(tvd);
845 		vdev_close(vd);
846 		vdev_free(vd);
847 	}
848 
849 	if (spa->spa_spares.sav_vdevs)
850 		kmem_free(spa->spa_spares.sav_vdevs,
851 		    spa->spa_spares.sav_count * sizeof (void *));
852 
853 	if (spa->spa_spares.sav_config == NULL)
854 		nspares = 0;
855 	else
856 		VERIFY(nvlist_lookup_nvlist_array(spa->spa_spares.sav_config,
857 		    ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0);
858 
859 	spa->spa_spares.sav_count = (int)nspares;
860 	spa->spa_spares.sav_vdevs = NULL;
861 
862 	if (nspares == 0)
863 		return;
864 
865 	/*
866 	 * Construct the array of vdevs, opening them to get status in the
867 	 * process.   For each spare, there is potentially two different vdev_t
868 	 * structures associated with it: one in the list of spares (used only
869 	 * for basic validation purposes) and one in the active vdev
870 	 * configuration (if it's spared in).  During this phase we open and
871 	 * validate each vdev on the spare list.  If the vdev also exists in the
872 	 * active configuration, then we also mark this vdev as an active spare.
873 	 */
874 	spa->spa_spares.sav_vdevs = kmem_alloc(nspares * sizeof (void *),
875 	    KM_SLEEP);
876 	for (i = 0; i < spa->spa_spares.sav_count; i++) {
877 		VERIFY(spa_config_parse(spa, &vd, spares[i], NULL, 0,
878 		    VDEV_ALLOC_SPARE) == 0);
879 		ASSERT(vd != NULL);
880 
881 		spa->spa_spares.sav_vdevs[i] = vd;
882 
883 		if ((tvd = spa_lookup_by_guid(spa, vd->vdev_guid,
884 		    B_FALSE)) != NULL) {
885 			if (!tvd->vdev_isspare)
886 				spa_spare_add(tvd);
887 
888 			/*
889 			 * We only mark the spare active if we were successfully
890 			 * able to load the vdev.  Otherwise, importing a pool
891 			 * with a bad active spare would result in strange
892 			 * behavior, because multiple pool would think the spare
893 			 * is actively in use.
894 			 *
895 			 * There is a vulnerability here to an equally bizarre
896 			 * circumstance, where a dead active spare is later
897 			 * brought back to life (onlined or otherwise).  Given
898 			 * the rarity of this scenario, and the extra complexity
899 			 * it adds, we ignore the possibility.
900 			 */
901 			if (!vdev_is_dead(tvd))
902 				spa_spare_activate(tvd);
903 		}
904 
905 		vd->vdev_top = vd;
906 		vd->vdev_aux = &spa->spa_spares;
907 
908 		if (vdev_open(vd) != 0)
909 			continue;
910 
911 		if (vdev_validate_aux(vd) == 0)
912 			spa_spare_add(vd);
913 	}
914 
915 	/*
916 	 * Recompute the stashed list of spares, with status information
917 	 * this time.
918 	 */
919 	VERIFY(nvlist_remove(spa->spa_spares.sav_config, ZPOOL_CONFIG_SPARES,
920 	    DATA_TYPE_NVLIST_ARRAY) == 0);
921 
922 	spares = kmem_alloc(spa->spa_spares.sav_count * sizeof (void *),
923 	    KM_SLEEP);
924 	for (i = 0; i < spa->spa_spares.sav_count; i++)
925 		spares[i] = vdev_config_generate(spa,
926 		    spa->spa_spares.sav_vdevs[i], B_TRUE, B_TRUE, B_FALSE);
927 	VERIFY(nvlist_add_nvlist_array(spa->spa_spares.sav_config,
928 	    ZPOOL_CONFIG_SPARES, spares, spa->spa_spares.sav_count) == 0);
929 	for (i = 0; i < spa->spa_spares.sav_count; i++)
930 		nvlist_free(spares[i]);
931 	kmem_free(spares, spa->spa_spares.sav_count * sizeof (void *));
932 }
933 
934 /*
935  * Load (or re-load) the current list of vdevs describing the active l2cache for
936  * this pool.  When this is called, we have some form of basic information in
937  * 'spa_l2cache.sav_config'.  We parse this into vdevs, try to open them, and
938  * then re-generate a more complete list including status information.
939  * Devices which are already active have their details maintained, and are
940  * not re-opened.
941  */
942 static void
943 spa_load_l2cache(spa_t *spa)
944 {
945 	nvlist_t **l2cache;
946 	uint_t nl2cache;
947 	int i, j, oldnvdevs;
948 	uint64_t guid;
949 	vdev_t *vd, **oldvdevs, **newvdevs;
950 	spa_aux_vdev_t *sav = &spa->spa_l2cache;
951 
952 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
953 
954 	if (sav->sav_config != NULL) {
955 		VERIFY(nvlist_lookup_nvlist_array(sav->sav_config,
956 		    ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0);
957 		newvdevs = kmem_alloc(nl2cache * sizeof (void *), KM_SLEEP);
958 	} else {
959 		nl2cache = 0;
960 	}
961 
962 	oldvdevs = sav->sav_vdevs;
963 	oldnvdevs = sav->sav_count;
964 	sav->sav_vdevs = NULL;
965 	sav->sav_count = 0;
966 
967 	/*
968 	 * Process new nvlist of vdevs.
969 	 */
970 	for (i = 0; i < nl2cache; i++) {
971 		VERIFY(nvlist_lookup_uint64(l2cache[i], ZPOOL_CONFIG_GUID,
972 		    &guid) == 0);
973 
974 		newvdevs[i] = NULL;
975 		for (j = 0; j < oldnvdevs; j++) {
976 			vd = oldvdevs[j];
977 			if (vd != NULL && guid == vd->vdev_guid) {
978 				/*
979 				 * Retain previous vdev for add/remove ops.
980 				 */
981 				newvdevs[i] = vd;
982 				oldvdevs[j] = NULL;
983 				break;
984 			}
985 		}
986 
987 		if (newvdevs[i] == NULL) {
988 			/*
989 			 * Create new vdev
990 			 */
991 			VERIFY(spa_config_parse(spa, &vd, l2cache[i], NULL, 0,
992 			    VDEV_ALLOC_L2CACHE) == 0);
993 			ASSERT(vd != NULL);
994 			newvdevs[i] = vd;
995 
996 			/*
997 			 * Commit this vdev as an l2cache device,
998 			 * even if it fails to open.
999 			 */
1000 			spa_l2cache_add(vd);
1001 
1002 			vd->vdev_top = vd;
1003 			vd->vdev_aux = sav;
1004 
1005 			spa_l2cache_activate(vd);
1006 
1007 			if (vdev_open(vd) != 0)
1008 				continue;
1009 
1010 			(void) vdev_validate_aux(vd);
1011 
1012 			if (!vdev_is_dead(vd))
1013 				l2arc_add_vdev(spa, vd);
1014 		}
1015 	}
1016 
1017 	/*
1018 	 * Purge vdevs that were dropped
1019 	 */
1020 	for (i = 0; i < oldnvdevs; i++) {
1021 		uint64_t pool;
1022 
1023 		vd = oldvdevs[i];
1024 		if (vd != NULL) {
1025 			if (spa_l2cache_exists(vd->vdev_guid, &pool) &&
1026 			    pool != 0ULL && l2arc_vdev_present(vd))
1027 				l2arc_remove_vdev(vd);
1028 			(void) vdev_close(vd);
1029 			spa_l2cache_remove(vd);
1030 		}
1031 	}
1032 
1033 	if (oldvdevs)
1034 		kmem_free(oldvdevs, oldnvdevs * sizeof (void *));
1035 
1036 	if (sav->sav_config == NULL)
1037 		goto out;
1038 
1039 	sav->sav_vdevs = newvdevs;
1040 	sav->sav_count = (int)nl2cache;
1041 
1042 	/*
1043 	 * Recompute the stashed list of l2cache devices, with status
1044 	 * information this time.
1045 	 */
1046 	VERIFY(nvlist_remove(sav->sav_config, ZPOOL_CONFIG_L2CACHE,
1047 	    DATA_TYPE_NVLIST_ARRAY) == 0);
1048 
1049 	l2cache = kmem_alloc(sav->sav_count * sizeof (void *), KM_SLEEP);
1050 	for (i = 0; i < sav->sav_count; i++)
1051 		l2cache[i] = vdev_config_generate(spa,
1052 		    sav->sav_vdevs[i], B_TRUE, B_FALSE, B_TRUE);
1053 	VERIFY(nvlist_add_nvlist_array(sav->sav_config,
1054 	    ZPOOL_CONFIG_L2CACHE, l2cache, sav->sav_count) == 0);
1055 out:
1056 	for (i = 0; i < sav->sav_count; i++)
1057 		nvlist_free(l2cache[i]);
1058 	if (sav->sav_count)
1059 		kmem_free(l2cache, sav->sav_count * sizeof (void *));
1060 }
1061 
1062 static int
1063 load_nvlist(spa_t *spa, uint64_t obj, nvlist_t **value)
1064 {
1065 	dmu_buf_t *db;
1066 	char *packed = NULL;
1067 	size_t nvsize = 0;
1068 	int error;
1069 	*value = NULL;
1070 
1071 	VERIFY(0 == dmu_bonus_hold(spa->spa_meta_objset, obj, FTAG, &db));
1072 	nvsize = *(uint64_t *)db->db_data;
1073 	dmu_buf_rele(db, FTAG);
1074 
1075 	packed = kmem_alloc(nvsize, KM_SLEEP);
1076 	error = dmu_read(spa->spa_meta_objset, obj, 0, nvsize, packed,
1077 	    DMU_READ_PREFETCH);
1078 	if (error == 0)
1079 		error = nvlist_unpack(packed, nvsize, value, 0);
1080 	kmem_free(packed, nvsize);
1081 
1082 	return (error);
1083 }
1084 
1085 /*
1086  * Checks to see if the given vdev could not be opened, in which case we post a
1087  * sysevent to notify the autoreplace code that the device has been removed.
1088  */
1089 static void
1090 spa_check_removed(vdev_t *vd)
1091 {
1092 	for (int c = 0; c < vd->vdev_children; c++)
1093 		spa_check_removed(vd->vdev_child[c]);
1094 
1095 	if (vd->vdev_ops->vdev_op_leaf && vdev_is_dead(vd)) {
1096 		zfs_post_autoreplace(vd->vdev_spa, vd);
1097 		spa_event_notify(vd->vdev_spa, vd, ESC_ZFS_VDEV_CHECK);
1098 	}
1099 }
1100 
1101 /*
1102  * Load the slog device state from the config object since it's possible
1103  * that the label does not contain the most up-to-date information.
1104  */
1105 void
1106 spa_load_log_state(spa_t *spa, nvlist_t *nv)
1107 {
1108 	vdev_t *ovd, *rvd = spa->spa_root_vdev;
1109 
1110 	/*
1111 	 * Load the original root vdev tree from the passed config.
1112 	 */
1113 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1114 	VERIFY(spa_config_parse(spa, &ovd, nv, NULL, 0, VDEV_ALLOC_LOAD) == 0);
1115 
1116 	for (int c = 0; c < rvd->vdev_children; c++) {
1117 		vdev_t *cvd = rvd->vdev_child[c];
1118 		if (cvd->vdev_islog)
1119 			vdev_load_log_state(cvd, ovd->vdev_child[c]);
1120 	}
1121 	vdev_free(ovd);
1122 	spa_config_exit(spa, SCL_ALL, FTAG);
1123 }
1124 
1125 /*
1126  * Check for missing log devices
1127  */
1128 int
1129 spa_check_logs(spa_t *spa)
1130 {
1131 	switch (spa->spa_log_state) {
1132 	case SPA_LOG_MISSING:
1133 		/* need to recheck in case slog has been restored */
1134 	case SPA_LOG_UNKNOWN:
1135 		if (dmu_objset_find(spa->spa_name, zil_check_log_chain, NULL,
1136 		    DS_FIND_CHILDREN)) {
1137 			spa->spa_log_state = SPA_LOG_MISSING;
1138 			return (1);
1139 		}
1140 		break;
1141 	}
1142 	return (0);
1143 }
1144 
1145 static void
1146 spa_aux_check_removed(spa_aux_vdev_t *sav)
1147 {
1148 	int i;
1149 
1150 	for (i = 0; i < sav->sav_count; i++)
1151 		spa_check_removed(sav->sav_vdevs[i]);
1152 }
1153 
1154 /*
1155  * Load an existing storage pool, using the pool's builtin spa_config as a
1156  * source of configuration information.
1157  */
1158 static int
1159 spa_load(spa_t *spa, nvlist_t *config, spa_load_state_t state, int mosconfig)
1160 {
1161 	int error = 0;
1162 	nvlist_t *nvconfig, *nvroot = NULL;
1163 	vdev_t *rvd;
1164 	uberblock_t *ub = &spa->spa_uberblock;
1165 	uint64_t config_cache_txg = spa->spa_config_txg;
1166 	uint64_t pool_guid;
1167 	uint64_t version;
1168 	uint64_t autoreplace = 0;
1169 	int orig_mode = spa->spa_mode;
1170 	char *ereport = FM_EREPORT_ZFS_POOL;
1171 
1172 	/*
1173 	 * If this is an untrusted config, access the pool in read-only mode.
1174 	 * This prevents things like resilvering recently removed devices.
1175 	 */
1176 	if (!mosconfig)
1177 		spa->spa_mode = FREAD;
1178 
1179 	ASSERT(MUTEX_HELD(&spa_namespace_lock));
1180 
1181 	spa->spa_load_state = state;
1182 
1183 	if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nvroot) ||
1184 	    nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID, &pool_guid)) {
1185 		error = EINVAL;
1186 		goto out;
1187 	}
1188 
1189 	/*
1190 	 * Versioning wasn't explicitly added to the label until later, so if
1191 	 * it's not present treat it as the initial version.
1192 	 */
1193 	if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_VERSION, &version) != 0)
1194 		version = SPA_VERSION_INITIAL;
1195 
1196 	(void) nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
1197 	    &spa->spa_config_txg);
1198 
1199 	if ((state == SPA_LOAD_IMPORT || state == SPA_LOAD_TRYIMPORT) &&
1200 	    spa_guid_exists(pool_guid, 0)) {
1201 		error = EEXIST;
1202 		goto out;
1203 	}
1204 
1205 	spa->spa_load_guid = pool_guid;
1206 
1207 	/*
1208 	 * Create "The Godfather" zio to hold all async IOs
1209 	 */
1210 	spa->spa_async_zio_root = zio_root(spa, NULL, NULL,
1211 	    ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_GODFATHER);
1212 
1213 	/*
1214 	 * Parse the configuration into a vdev tree.  We explicitly set the
1215 	 * value that will be returned by spa_version() since parsing the
1216 	 * configuration requires knowing the version number.
1217 	 */
1218 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1219 	spa->spa_ubsync.ub_version = version;
1220 	error = spa_config_parse(spa, &rvd, nvroot, NULL, 0, VDEV_ALLOC_LOAD);
1221 	spa_config_exit(spa, SCL_ALL, FTAG);
1222 
1223 	if (error != 0)
1224 		goto out;
1225 
1226 	ASSERT(spa->spa_root_vdev == rvd);
1227 	ASSERT(spa_guid(spa) == pool_guid);
1228 
1229 	/*
1230 	 * Try to open all vdevs, loading each label in the process.
1231 	 */
1232 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1233 	error = vdev_open(rvd);
1234 	spa_config_exit(spa, SCL_ALL, FTAG);
1235 	if (error != 0)
1236 		goto out;
1237 
1238 	/*
1239 	 * We need to validate the vdev labels against the configuration that
1240 	 * we have in hand, which is dependent on the setting of mosconfig. If
1241 	 * mosconfig is true then we're validating the vdev labels based on
1242 	 * that config. Otherwise, we're validating against the cached config
1243 	 * (zpool.cache) that was read when we loaded the zfs module, and then
1244 	 * later we will recursively call spa_load() and validate against
1245 	 * the vdev config.
1246 	 */
1247 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1248 	error = vdev_validate(rvd);
1249 	spa_config_exit(spa, SCL_ALL, FTAG);
1250 	if (error != 0)
1251 		goto out;
1252 
1253 	if (rvd->vdev_state <= VDEV_STATE_CANT_OPEN) {
1254 		error = ENXIO;
1255 		goto out;
1256 	}
1257 
1258 	/*
1259 	 * Find the best uberblock.
1260 	 */
1261 	vdev_uberblock_load(NULL, rvd, ub);
1262 
1263 	/*
1264 	 * If we weren't able to find a single valid uberblock, return failure.
1265 	 */
1266 	if (ub->ub_txg == 0) {
1267 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1268 		    VDEV_AUX_CORRUPT_DATA);
1269 		error = ENXIO;
1270 		goto out;
1271 	}
1272 
1273 	/*
1274 	 * If the pool is newer than the code, we can't open it.
1275 	 */
1276 	if (ub->ub_version > SPA_VERSION) {
1277 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1278 		    VDEV_AUX_VERSION_NEWER);
1279 		error = ENOTSUP;
1280 		goto out;
1281 	}
1282 
1283 	/*
1284 	 * If the vdev guid sum doesn't match the uberblock, we have an
1285 	 * incomplete configuration.
1286 	 */
1287 	if (rvd->vdev_guid_sum != ub->ub_guid_sum && mosconfig) {
1288 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1289 		    VDEV_AUX_BAD_GUID_SUM);
1290 		error = ENXIO;
1291 		goto out;
1292 	}
1293 
1294 	/*
1295 	 * Initialize internal SPA structures.
1296 	 */
1297 	spa->spa_state = POOL_STATE_ACTIVE;
1298 	spa->spa_ubsync = spa->spa_uberblock;
1299 	spa->spa_first_txg = spa_last_synced_txg(spa) + 1;
1300 	error = dsl_pool_open(spa, spa->spa_first_txg, &spa->spa_dsl_pool);
1301 	if (error) {
1302 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1303 		    VDEV_AUX_CORRUPT_DATA);
1304 		goto out;
1305 	}
1306 	spa->spa_meta_objset = spa->spa_dsl_pool->dp_meta_objset;
1307 
1308 	if (zap_lookup(spa->spa_meta_objset,
1309 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_CONFIG,
1310 	    sizeof (uint64_t), 1, &spa->spa_config_object) != 0) {
1311 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1312 		    VDEV_AUX_CORRUPT_DATA);
1313 		error = EIO;
1314 		goto out;
1315 	}
1316 
1317 	if (load_nvlist(spa, spa->spa_config_object, &nvconfig) != 0) {
1318 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1319 		    VDEV_AUX_CORRUPT_DATA);
1320 		error = EIO;
1321 		goto out;
1322 	}
1323 
1324 	if (!mosconfig) {
1325 		uint64_t hostid;
1326 
1327 		if (!spa_is_root(spa) && nvlist_lookup_uint64(nvconfig,
1328 		    ZPOOL_CONFIG_HOSTID, &hostid) == 0) {
1329 			char *hostname;
1330 			unsigned long myhostid = 0;
1331 
1332 			VERIFY(nvlist_lookup_string(nvconfig,
1333 			    ZPOOL_CONFIG_HOSTNAME, &hostname) == 0);
1334 
1335 #ifdef	_KERNEL
1336 			myhostid = zone_get_hostid(NULL);
1337 #else	/* _KERNEL */
1338 			/*
1339 			 * We're emulating the system's hostid in userland, so
1340 			 * we can't use zone_get_hostid().
1341 			 */
1342 			(void) ddi_strtoul(hw_serial, NULL, 10, &myhostid);
1343 #endif	/* _KERNEL */
1344 			if (hostid != 0 && myhostid != 0 &&
1345 			    hostid != myhostid) {
1346 				cmn_err(CE_WARN, "pool '%s' could not be "
1347 				    "loaded as it was last accessed by "
1348 				    "another system (host: %s hostid: 0x%lx). "
1349 				    "See: http://www.sun.com/msg/ZFS-8000-EY",
1350 				    spa_name(spa), hostname,
1351 				    (unsigned long)hostid);
1352 				error = EBADF;
1353 				goto out;
1354 			}
1355 		}
1356 
1357 		spa_config_set(spa, nvconfig);
1358 		spa_unload(spa);
1359 		spa_deactivate(spa);
1360 		spa_activate(spa, orig_mode);
1361 
1362 		return (spa_load(spa, nvconfig, state, B_TRUE));
1363 	}
1364 
1365 	if (zap_lookup(spa->spa_meta_objset,
1366 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_SYNC_BPLIST,
1367 	    sizeof (uint64_t), 1, &spa->spa_sync_bplist_obj) != 0) {
1368 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1369 		    VDEV_AUX_CORRUPT_DATA);
1370 		error = EIO;
1371 		goto out;
1372 	}
1373 
1374 	/*
1375 	 * Load the bit that tells us to use the new accounting function
1376 	 * (raid-z deflation).  If we have an older pool, this will not
1377 	 * be present.
1378 	 */
1379 	error = zap_lookup(spa->spa_meta_objset,
1380 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_DEFLATE,
1381 	    sizeof (uint64_t), 1, &spa->spa_deflate);
1382 	if (error != 0 && error != ENOENT) {
1383 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1384 		    VDEV_AUX_CORRUPT_DATA);
1385 		error = EIO;
1386 		goto out;
1387 	}
1388 
1389 	/*
1390 	 * Load the persistent error log.  If we have an older pool, this will
1391 	 * not be present.
1392 	 */
1393 	error = zap_lookup(spa->spa_meta_objset,
1394 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ERRLOG_LAST,
1395 	    sizeof (uint64_t), 1, &spa->spa_errlog_last);
1396 	if (error != 0 && error != ENOENT) {
1397 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1398 		    VDEV_AUX_CORRUPT_DATA);
1399 		error = EIO;
1400 		goto out;
1401 	}
1402 
1403 	error = zap_lookup(spa->spa_meta_objset,
1404 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ERRLOG_SCRUB,
1405 	    sizeof (uint64_t), 1, &spa->spa_errlog_scrub);
1406 	if (error != 0 && error != ENOENT) {
1407 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1408 		    VDEV_AUX_CORRUPT_DATA);
1409 		error = EIO;
1410 		goto out;
1411 	}
1412 
1413 	/*
1414 	 * Load the history object.  If we have an older pool, this
1415 	 * will not be present.
1416 	 */
1417 	error = zap_lookup(spa->spa_meta_objset,
1418 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_HISTORY,
1419 	    sizeof (uint64_t), 1, &spa->spa_history);
1420 	if (error != 0 && error != ENOENT) {
1421 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1422 		    VDEV_AUX_CORRUPT_DATA);
1423 		error = EIO;
1424 		goto out;
1425 	}
1426 
1427 	/*
1428 	 * Load any hot spares for this pool.
1429 	 */
1430 	error = zap_lookup(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
1431 	    DMU_POOL_SPARES, sizeof (uint64_t), 1, &spa->spa_spares.sav_object);
1432 	if (error != 0 && error != ENOENT) {
1433 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1434 		    VDEV_AUX_CORRUPT_DATA);
1435 		error = EIO;
1436 		goto out;
1437 	}
1438 	if (error == 0) {
1439 		ASSERT(spa_version(spa) >= SPA_VERSION_SPARES);
1440 		if (load_nvlist(spa, spa->spa_spares.sav_object,
1441 		    &spa->spa_spares.sav_config) != 0) {
1442 			vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1443 			    VDEV_AUX_CORRUPT_DATA);
1444 			error = EIO;
1445 			goto out;
1446 		}
1447 
1448 		spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1449 		spa_load_spares(spa);
1450 		spa_config_exit(spa, SCL_ALL, FTAG);
1451 	}
1452 
1453 	/*
1454 	 * Load any level 2 ARC devices for this pool.
1455 	 */
1456 	error = zap_lookup(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
1457 	    DMU_POOL_L2CACHE, sizeof (uint64_t), 1,
1458 	    &spa->spa_l2cache.sav_object);
1459 	if (error != 0 && error != ENOENT) {
1460 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1461 		    VDEV_AUX_CORRUPT_DATA);
1462 		error = EIO;
1463 		goto out;
1464 	}
1465 	if (error == 0) {
1466 		ASSERT(spa_version(spa) >= SPA_VERSION_L2CACHE);
1467 		if (load_nvlist(spa, spa->spa_l2cache.sav_object,
1468 		    &spa->spa_l2cache.sav_config) != 0) {
1469 			vdev_set_state(rvd, B_TRUE,
1470 			    VDEV_STATE_CANT_OPEN,
1471 			    VDEV_AUX_CORRUPT_DATA);
1472 			error = EIO;
1473 			goto out;
1474 		}
1475 
1476 		spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1477 		spa_load_l2cache(spa);
1478 		spa_config_exit(spa, SCL_ALL, FTAG);
1479 	}
1480 
1481 	VERIFY(nvlist_lookup_nvlist(nvconfig, ZPOOL_CONFIG_VDEV_TREE,
1482 	    &nvroot) == 0);
1483 	spa_load_log_state(spa, nvroot);
1484 	nvlist_free(nvconfig);
1485 
1486 	if (spa_check_logs(spa)) {
1487 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1488 		    VDEV_AUX_BAD_LOG);
1489 		error = ENXIO;
1490 		ereport = FM_EREPORT_ZFS_LOG_REPLAY;
1491 		goto out;
1492 	}
1493 
1494 
1495 	spa->spa_delegation = zpool_prop_default_numeric(ZPOOL_PROP_DELEGATION);
1496 
1497 	error = zap_lookup(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
1498 	    DMU_POOL_PROPS, sizeof (uint64_t), 1, &spa->spa_pool_props_object);
1499 
1500 	if (error && error != ENOENT) {
1501 		vdev_set_state(rvd, B_TRUE, VDEV_STATE_CANT_OPEN,
1502 		    VDEV_AUX_CORRUPT_DATA);
1503 		error = EIO;
1504 		goto out;
1505 	}
1506 
1507 	if (error == 0) {
1508 		(void) zap_lookup(spa->spa_meta_objset,
1509 		    spa->spa_pool_props_object,
1510 		    zpool_prop_to_name(ZPOOL_PROP_BOOTFS),
1511 		    sizeof (uint64_t), 1, &spa->spa_bootfs);
1512 		(void) zap_lookup(spa->spa_meta_objset,
1513 		    spa->spa_pool_props_object,
1514 		    zpool_prop_to_name(ZPOOL_PROP_AUTOREPLACE),
1515 		    sizeof (uint64_t), 1, &autoreplace);
1516 		spa->spa_autoreplace = (autoreplace != 0);
1517 		(void) zap_lookup(spa->spa_meta_objset,
1518 		    spa->spa_pool_props_object,
1519 		    zpool_prop_to_name(ZPOOL_PROP_DELEGATION),
1520 		    sizeof (uint64_t), 1, &spa->spa_delegation);
1521 		(void) zap_lookup(spa->spa_meta_objset,
1522 		    spa->spa_pool_props_object,
1523 		    zpool_prop_to_name(ZPOOL_PROP_FAILUREMODE),
1524 		    sizeof (uint64_t), 1, &spa->spa_failmode);
1525 		(void) zap_lookup(spa->spa_meta_objset,
1526 		    spa->spa_pool_props_object,
1527 		    zpool_prop_to_name(ZPOOL_PROP_AUTOEXPAND),
1528 		    sizeof (uint64_t), 1, &spa->spa_autoexpand);
1529 	}
1530 
1531 	/*
1532 	 * If the 'autoreplace' property is set, then post a resource notifying
1533 	 * the ZFS DE that it should not issue any faults for unopenable
1534 	 * devices.  We also iterate over the vdevs, and post a sysevent for any
1535 	 * unopenable vdevs so that the normal autoreplace handler can take
1536 	 * over.
1537 	 */
1538 	if (spa->spa_autoreplace && state != SPA_LOAD_TRYIMPORT) {
1539 		spa_check_removed(spa->spa_root_vdev);
1540 		/*
1541 		 * For the import case, this is done in spa_import(), because
1542 		 * at this point we're using the spare definitions from
1543 		 * the MOS config, not necessarily from the userland config.
1544 		 */
1545 		if (state != SPA_LOAD_IMPORT) {
1546 			spa_aux_check_removed(&spa->spa_spares);
1547 			spa_aux_check_removed(&spa->spa_l2cache);
1548 		}
1549 	}
1550 
1551 	/*
1552 	 * Load the vdev state for all toplevel vdevs.
1553 	 */
1554 	vdev_load(rvd);
1555 
1556 	/*
1557 	 * Propagate the leaf DTLs we just loaded all the way up the tree.
1558 	 */
1559 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1560 	vdev_dtl_reassess(rvd, 0, 0, B_FALSE);
1561 	spa_config_exit(spa, SCL_ALL, FTAG);
1562 
1563 	/*
1564 	 * Check the state of the root vdev.  If it can't be opened, it
1565 	 * indicates one or more toplevel vdevs are faulted.
1566 	 */
1567 	if (rvd->vdev_state <= VDEV_STATE_CANT_OPEN) {
1568 		error = ENXIO;
1569 		goto out;
1570 	}
1571 
1572 	if (spa_writeable(spa)) {
1573 		dmu_tx_t *tx;
1574 		int need_update = B_FALSE;
1575 
1576 		ASSERT(state != SPA_LOAD_TRYIMPORT);
1577 
1578 		/*
1579 		 * Claim log blocks that haven't been committed yet.
1580 		 * This must all happen in a single txg.
1581 		 */
1582 		tx = dmu_tx_create_assigned(spa_get_dsl(spa),
1583 		    spa_first_txg(spa));
1584 		(void) dmu_objset_find(spa_name(spa),
1585 		    zil_claim, tx, DS_FIND_CHILDREN);
1586 		dmu_tx_commit(tx);
1587 
1588 		spa->spa_log_state = SPA_LOG_GOOD;
1589 		spa->spa_sync_on = B_TRUE;
1590 		txg_sync_start(spa->spa_dsl_pool);
1591 
1592 		/*
1593 		 * Wait for all claims to sync.
1594 		 */
1595 		txg_wait_synced(spa->spa_dsl_pool, 0);
1596 
1597 		/*
1598 		 * If the config cache is stale, or we have uninitialized
1599 		 * metaslabs (see spa_vdev_add()), then update the config.
1600 		 *
1601 		 * If spa_load_verbatim is true, trust the current
1602 		 * in-core spa_config and update the disk labels.
1603 		 */
1604 		if (config_cache_txg != spa->spa_config_txg ||
1605 		    state == SPA_LOAD_IMPORT || spa->spa_load_verbatim)
1606 			need_update = B_TRUE;
1607 
1608 		for (int c = 0; c < rvd->vdev_children; c++)
1609 			if (rvd->vdev_child[c]->vdev_ms_array == 0)
1610 				need_update = B_TRUE;
1611 
1612 		/*
1613 		 * Update the config cache asychronously in case we're the
1614 		 * root pool, in which case the config cache isn't writable yet.
1615 		 */
1616 		if (need_update)
1617 			spa_async_request(spa, SPA_ASYNC_CONFIG_UPDATE);
1618 
1619 		/*
1620 		 * Check all DTLs to see if anything needs resilvering.
1621 		 */
1622 		if (vdev_resilver_needed(rvd, NULL, NULL))
1623 			spa_async_request(spa, SPA_ASYNC_RESILVER);
1624 
1625 		/*
1626 		 * Delete any inconsistent datasets.
1627 		 */
1628 		(void) dmu_objset_find(spa_name(spa),
1629 		    dsl_destroy_inconsistent, NULL, DS_FIND_CHILDREN);
1630 
1631 		/*
1632 		 * Clean up any stale temporary dataset userrefs.
1633 		 */
1634 		dsl_pool_clean_tmp_userrefs(spa->spa_dsl_pool);
1635 	}
1636 
1637 	error = 0;
1638 out:
1639 	spa->spa_minref = refcount_count(&spa->spa_refcount);
1640 	if (error && error != EBADF)
1641 		zfs_ereport_post(ereport, spa, NULL, NULL, 0, 0);
1642 	spa->spa_load_state = SPA_LOAD_NONE;
1643 	spa->spa_ena = 0;
1644 
1645 	return (error);
1646 }
1647 
1648 /*
1649  * Pool Open/Import
1650  *
1651  * The import case is identical to an open except that the configuration is sent
1652  * down from userland, instead of grabbed from the configuration cache.  For the
1653  * case of an open, the pool configuration will exist in the
1654  * POOL_STATE_UNINITIALIZED state.
1655  *
1656  * The stats information (gen/count/ustats) is used to gather vdev statistics at
1657  * the same time open the pool, without having to keep around the spa_t in some
1658  * ambiguous state.
1659  */
1660 static int
1661 spa_open_common(const char *pool, spa_t **spapp, void *tag, nvlist_t **config)
1662 {
1663 	spa_t *spa;
1664 	int error;
1665 	int locked = B_FALSE;
1666 
1667 	*spapp = NULL;
1668 
1669 	/*
1670 	 * As disgusting as this is, we need to support recursive calls to this
1671 	 * function because dsl_dir_open() is called during spa_load(), and ends
1672 	 * up calling spa_open() again.  The real fix is to figure out how to
1673 	 * avoid dsl_dir_open() calling this in the first place.
1674 	 */
1675 	if (mutex_owner(&spa_namespace_lock) != curthread) {
1676 		mutex_enter(&spa_namespace_lock);
1677 		locked = B_TRUE;
1678 	}
1679 
1680 	if ((spa = spa_lookup(pool)) == NULL) {
1681 		if (locked)
1682 			mutex_exit(&spa_namespace_lock);
1683 		return (ENOENT);
1684 	}
1685 	if (spa->spa_state == POOL_STATE_UNINITIALIZED) {
1686 
1687 		spa_activate(spa, spa_mode_global);
1688 
1689 		error = spa_load(spa, spa->spa_config, SPA_LOAD_OPEN, B_FALSE);
1690 
1691 		if (error == EBADF) {
1692 			/*
1693 			 * If vdev_validate() returns failure (indicated by
1694 			 * EBADF), it indicates that one of the vdevs indicates
1695 			 * that the pool has been exported or destroyed.  If
1696 			 * this is the case, the config cache is out of sync and
1697 			 * we should remove the pool from the namespace.
1698 			 */
1699 			spa_unload(spa);
1700 			spa_deactivate(spa);
1701 			spa_config_sync(spa, B_TRUE, B_TRUE);
1702 			spa_remove(spa);
1703 			if (locked)
1704 				mutex_exit(&spa_namespace_lock);
1705 			return (ENOENT);
1706 		}
1707 
1708 		if (error) {
1709 			/*
1710 			 * We can't open the pool, but we still have useful
1711 			 * information: the state of each vdev after the
1712 			 * attempted vdev_open().  Return this to the user.
1713 			 */
1714 			if (config != NULL && spa->spa_root_vdev != NULL)
1715 				*config = spa_config_generate(spa, NULL, -1ULL,
1716 				    B_TRUE);
1717 			spa_unload(spa);
1718 			spa_deactivate(spa);
1719 			spa->spa_last_open_failed = B_TRUE;
1720 			if (locked)
1721 				mutex_exit(&spa_namespace_lock);
1722 			*spapp = NULL;
1723 			return (error);
1724 		} else {
1725 			spa->spa_last_open_failed = B_FALSE;
1726 		}
1727 	}
1728 
1729 	spa_open_ref(spa, tag);
1730 
1731 	if (locked)
1732 		mutex_exit(&spa_namespace_lock);
1733 
1734 	*spapp = spa;
1735 
1736 	if (config != NULL)
1737 		*config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
1738 
1739 	return (0);
1740 }
1741 
1742 int
1743 spa_open(const char *name, spa_t **spapp, void *tag)
1744 {
1745 	return (spa_open_common(name, spapp, tag, NULL));
1746 }
1747 
1748 /*
1749  * Lookup the given spa_t, incrementing the inject count in the process,
1750  * preventing it from being exported or destroyed.
1751  */
1752 spa_t *
1753 spa_inject_addref(char *name)
1754 {
1755 	spa_t *spa;
1756 
1757 	mutex_enter(&spa_namespace_lock);
1758 	if ((spa = spa_lookup(name)) == NULL) {
1759 		mutex_exit(&spa_namespace_lock);
1760 		return (NULL);
1761 	}
1762 	spa->spa_inject_ref++;
1763 	mutex_exit(&spa_namespace_lock);
1764 
1765 	return (spa);
1766 }
1767 
1768 void
1769 spa_inject_delref(spa_t *spa)
1770 {
1771 	mutex_enter(&spa_namespace_lock);
1772 	spa->spa_inject_ref--;
1773 	mutex_exit(&spa_namespace_lock);
1774 }
1775 
1776 /*
1777  * Add spares device information to the nvlist.
1778  */
1779 static void
1780 spa_add_spares(spa_t *spa, nvlist_t *config)
1781 {
1782 	nvlist_t **spares;
1783 	uint_t i, nspares;
1784 	nvlist_t *nvroot;
1785 	uint64_t guid;
1786 	vdev_stat_t *vs;
1787 	uint_t vsc;
1788 	uint64_t pool;
1789 
1790 	ASSERT(spa_config_held(spa, SCL_CONFIG, RW_READER));
1791 
1792 	if (spa->spa_spares.sav_count == 0)
1793 		return;
1794 
1795 	VERIFY(nvlist_lookup_nvlist(config,
1796 	    ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
1797 	VERIFY(nvlist_lookup_nvlist_array(spa->spa_spares.sav_config,
1798 	    ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0);
1799 	if (nspares != 0) {
1800 		VERIFY(nvlist_add_nvlist_array(nvroot,
1801 		    ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
1802 		VERIFY(nvlist_lookup_nvlist_array(nvroot,
1803 		    ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0);
1804 
1805 		/*
1806 		 * Go through and find any spares which have since been
1807 		 * repurposed as an active spare.  If this is the case, update
1808 		 * their status appropriately.
1809 		 */
1810 		for (i = 0; i < nspares; i++) {
1811 			VERIFY(nvlist_lookup_uint64(spares[i],
1812 			    ZPOOL_CONFIG_GUID, &guid) == 0);
1813 			if (spa_spare_exists(guid, &pool, NULL) &&
1814 			    pool != 0ULL) {
1815 				VERIFY(nvlist_lookup_uint64_array(
1816 				    spares[i], ZPOOL_CONFIG_STATS,
1817 				    (uint64_t **)&vs, &vsc) == 0);
1818 				vs->vs_state = VDEV_STATE_CANT_OPEN;
1819 				vs->vs_aux = VDEV_AUX_SPARED;
1820 			}
1821 		}
1822 	}
1823 }
1824 
1825 /*
1826  * Add l2cache device information to the nvlist, including vdev stats.
1827  */
1828 static void
1829 spa_add_l2cache(spa_t *spa, nvlist_t *config)
1830 {
1831 	nvlist_t **l2cache;
1832 	uint_t i, j, nl2cache;
1833 	nvlist_t *nvroot;
1834 	uint64_t guid;
1835 	vdev_t *vd;
1836 	vdev_stat_t *vs;
1837 	uint_t vsc;
1838 
1839 	ASSERT(spa_config_held(spa, SCL_CONFIG, RW_READER));
1840 
1841 	if (spa->spa_l2cache.sav_count == 0)
1842 		return;
1843 
1844 	VERIFY(nvlist_lookup_nvlist(config,
1845 	    ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
1846 	VERIFY(nvlist_lookup_nvlist_array(spa->spa_l2cache.sav_config,
1847 	    ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0);
1848 	if (nl2cache != 0) {
1849 		VERIFY(nvlist_add_nvlist_array(nvroot,
1850 		    ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
1851 		VERIFY(nvlist_lookup_nvlist_array(nvroot,
1852 		    ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0);
1853 
1854 		/*
1855 		 * Update level 2 cache device stats.
1856 		 */
1857 
1858 		for (i = 0; i < nl2cache; i++) {
1859 			VERIFY(nvlist_lookup_uint64(l2cache[i],
1860 			    ZPOOL_CONFIG_GUID, &guid) == 0);
1861 
1862 			vd = NULL;
1863 			for (j = 0; j < spa->spa_l2cache.sav_count; j++) {
1864 				if (guid ==
1865 				    spa->spa_l2cache.sav_vdevs[j]->vdev_guid) {
1866 					vd = spa->spa_l2cache.sav_vdevs[j];
1867 					break;
1868 				}
1869 			}
1870 			ASSERT(vd != NULL);
1871 
1872 			VERIFY(nvlist_lookup_uint64_array(l2cache[i],
1873 			    ZPOOL_CONFIG_STATS, (uint64_t **)&vs, &vsc) == 0);
1874 			vdev_get_stats(vd, vs);
1875 		}
1876 	}
1877 }
1878 
1879 int
1880 spa_get_stats(const char *name, nvlist_t **config, char *altroot, size_t buflen)
1881 {
1882 	int error;
1883 	spa_t *spa;
1884 
1885 	*config = NULL;
1886 	error = spa_open_common(name, &spa, FTAG, config);
1887 
1888 	if (spa != NULL) {
1889 		/*
1890 		 * This still leaves a window of inconsistency where the spares
1891 		 * or l2cache devices could change and the config would be
1892 		 * self-inconsistent.
1893 		 */
1894 		spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
1895 
1896 		if (*config != NULL) {
1897 			VERIFY(nvlist_add_uint64(*config,
1898 			    ZPOOL_CONFIG_ERRCOUNT,
1899 			    spa_get_errlog_size(spa)) == 0);
1900 
1901 			if (spa_suspended(spa))
1902 				VERIFY(nvlist_add_uint64(*config,
1903 				    ZPOOL_CONFIG_SUSPENDED,
1904 				    spa->spa_failmode) == 0);
1905 
1906 			spa_add_spares(spa, *config);
1907 			spa_add_l2cache(spa, *config);
1908 		}
1909 	}
1910 
1911 	/*
1912 	 * We want to get the alternate root even for faulted pools, so we cheat
1913 	 * and call spa_lookup() directly.
1914 	 */
1915 	if (altroot) {
1916 		if (spa == NULL) {
1917 			mutex_enter(&spa_namespace_lock);
1918 			spa = spa_lookup(name);
1919 			if (spa)
1920 				spa_altroot(spa, altroot, buflen);
1921 			else
1922 				altroot[0] = '\0';
1923 			spa = NULL;
1924 			mutex_exit(&spa_namespace_lock);
1925 		} else {
1926 			spa_altroot(spa, altroot, buflen);
1927 		}
1928 	}
1929 
1930 	if (spa != NULL) {
1931 		spa_config_exit(spa, SCL_CONFIG, FTAG);
1932 		spa_close(spa, FTAG);
1933 	}
1934 
1935 	return (error);
1936 }
1937 
1938 /*
1939  * Validate that the auxiliary device array is well formed.  We must have an
1940  * array of nvlists, each which describes a valid leaf vdev.  If this is an
1941  * import (mode is VDEV_ALLOC_SPARE), then we allow corrupted spares to be
1942  * specified, as long as they are well-formed.
1943  */
1944 static int
1945 spa_validate_aux_devs(spa_t *spa, nvlist_t *nvroot, uint64_t crtxg, int mode,
1946     spa_aux_vdev_t *sav, const char *config, uint64_t version,
1947     vdev_labeltype_t label)
1948 {
1949 	nvlist_t **dev;
1950 	uint_t i, ndev;
1951 	vdev_t *vd;
1952 	int error;
1953 
1954 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1955 
1956 	/*
1957 	 * It's acceptable to have no devs specified.
1958 	 */
1959 	if (nvlist_lookup_nvlist_array(nvroot, config, &dev, &ndev) != 0)
1960 		return (0);
1961 
1962 	if (ndev == 0)
1963 		return (EINVAL);
1964 
1965 	/*
1966 	 * Make sure the pool is formatted with a version that supports this
1967 	 * device type.
1968 	 */
1969 	if (spa_version(spa) < version)
1970 		return (ENOTSUP);
1971 
1972 	/*
1973 	 * Set the pending device list so we correctly handle device in-use
1974 	 * checking.
1975 	 */
1976 	sav->sav_pending = dev;
1977 	sav->sav_npending = ndev;
1978 
1979 	for (i = 0; i < ndev; i++) {
1980 		if ((error = spa_config_parse(spa, &vd, dev[i], NULL, 0,
1981 		    mode)) != 0)
1982 			goto out;
1983 
1984 		if (!vd->vdev_ops->vdev_op_leaf) {
1985 			vdev_free(vd);
1986 			error = EINVAL;
1987 			goto out;
1988 		}
1989 
1990 		/*
1991 		 * The L2ARC currently only supports disk devices in
1992 		 * kernel context.  For user-level testing, we allow it.
1993 		 */
1994 #ifdef _KERNEL
1995 		if ((strcmp(config, ZPOOL_CONFIG_L2CACHE) == 0) &&
1996 		    strcmp(vd->vdev_ops->vdev_op_type, VDEV_TYPE_DISK) != 0) {
1997 			error = ENOTBLK;
1998 			goto out;
1999 		}
2000 #endif
2001 		vd->vdev_top = vd;
2002 
2003 		if ((error = vdev_open(vd)) == 0 &&
2004 		    (error = vdev_label_init(vd, crtxg, label)) == 0) {
2005 			VERIFY(nvlist_add_uint64(dev[i], ZPOOL_CONFIG_GUID,
2006 			    vd->vdev_guid) == 0);
2007 		}
2008 
2009 		vdev_free(vd);
2010 
2011 		if (error &&
2012 		    (mode != VDEV_ALLOC_SPARE && mode != VDEV_ALLOC_L2CACHE))
2013 			goto out;
2014 		else
2015 			error = 0;
2016 	}
2017 
2018 out:
2019 	sav->sav_pending = NULL;
2020 	sav->sav_npending = 0;
2021 	return (error);
2022 }
2023 
2024 static int
2025 spa_validate_aux(spa_t *spa, nvlist_t *nvroot, uint64_t crtxg, int mode)
2026 {
2027 	int error;
2028 
2029 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
2030 
2031 	if ((error = spa_validate_aux_devs(spa, nvroot, crtxg, mode,
2032 	    &spa->spa_spares, ZPOOL_CONFIG_SPARES, SPA_VERSION_SPARES,
2033 	    VDEV_LABEL_SPARE)) != 0) {
2034 		return (error);
2035 	}
2036 
2037 	return (spa_validate_aux_devs(spa, nvroot, crtxg, mode,
2038 	    &spa->spa_l2cache, ZPOOL_CONFIG_L2CACHE, SPA_VERSION_L2CACHE,
2039 	    VDEV_LABEL_L2CACHE));
2040 }
2041 
2042 static void
2043 spa_set_aux_vdevs(spa_aux_vdev_t *sav, nvlist_t **devs, int ndevs,
2044     const char *config)
2045 {
2046 	int i;
2047 
2048 	if (sav->sav_config != NULL) {
2049 		nvlist_t **olddevs;
2050 		uint_t oldndevs;
2051 		nvlist_t **newdevs;
2052 
2053 		/*
2054 		 * Generate new dev list by concatentating with the
2055 		 * current dev list.
2056 		 */
2057 		VERIFY(nvlist_lookup_nvlist_array(sav->sav_config, config,
2058 		    &olddevs, &oldndevs) == 0);
2059 
2060 		newdevs = kmem_alloc(sizeof (void *) *
2061 		    (ndevs + oldndevs), KM_SLEEP);
2062 		for (i = 0; i < oldndevs; i++)
2063 			VERIFY(nvlist_dup(olddevs[i], &newdevs[i],
2064 			    KM_SLEEP) == 0);
2065 		for (i = 0; i < ndevs; i++)
2066 			VERIFY(nvlist_dup(devs[i], &newdevs[i + oldndevs],
2067 			    KM_SLEEP) == 0);
2068 
2069 		VERIFY(nvlist_remove(sav->sav_config, config,
2070 		    DATA_TYPE_NVLIST_ARRAY) == 0);
2071 
2072 		VERIFY(nvlist_add_nvlist_array(sav->sav_config,
2073 		    config, newdevs, ndevs + oldndevs) == 0);
2074 		for (i = 0; i < oldndevs + ndevs; i++)
2075 			nvlist_free(newdevs[i]);
2076 		kmem_free(newdevs, (oldndevs + ndevs) * sizeof (void *));
2077 	} else {
2078 		/*
2079 		 * Generate a new dev list.
2080 		 */
2081 		VERIFY(nvlist_alloc(&sav->sav_config, NV_UNIQUE_NAME,
2082 		    KM_SLEEP) == 0);
2083 		VERIFY(nvlist_add_nvlist_array(sav->sav_config, config,
2084 		    devs, ndevs) == 0);
2085 	}
2086 }
2087 
2088 /*
2089  * Stop and drop level 2 ARC devices
2090  */
2091 void
2092 spa_l2cache_drop(spa_t *spa)
2093 {
2094 	vdev_t *vd;
2095 	int i;
2096 	spa_aux_vdev_t *sav = &spa->spa_l2cache;
2097 
2098 	for (i = 0; i < sav->sav_count; i++) {
2099 		uint64_t pool;
2100 
2101 		vd = sav->sav_vdevs[i];
2102 		ASSERT(vd != NULL);
2103 
2104 		if (spa_l2cache_exists(vd->vdev_guid, &pool) &&
2105 		    pool != 0ULL && l2arc_vdev_present(vd))
2106 			l2arc_remove_vdev(vd);
2107 		if (vd->vdev_isl2cache)
2108 			spa_l2cache_remove(vd);
2109 		vdev_clear_stats(vd);
2110 		(void) vdev_close(vd);
2111 	}
2112 }
2113 
2114 /*
2115  * Pool Creation
2116  */
2117 int
2118 spa_create(const char *pool, nvlist_t *nvroot, nvlist_t *props,
2119     const char *history_str, nvlist_t *zplprops)
2120 {
2121 	spa_t *spa;
2122 	char *altroot = NULL;
2123 	vdev_t *rvd;
2124 	dsl_pool_t *dp;
2125 	dmu_tx_t *tx;
2126 	int error = 0;
2127 	uint64_t txg = TXG_INITIAL;
2128 	nvlist_t **spares, **l2cache;
2129 	uint_t nspares, nl2cache;
2130 	uint64_t version;
2131 
2132 	/*
2133 	 * If this pool already exists, return failure.
2134 	 */
2135 	mutex_enter(&spa_namespace_lock);
2136 	if (spa_lookup(pool) != NULL) {
2137 		mutex_exit(&spa_namespace_lock);
2138 		return (EEXIST);
2139 	}
2140 
2141 	/*
2142 	 * Allocate a new spa_t structure.
2143 	 */
2144 	(void) nvlist_lookup_string(props,
2145 	    zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
2146 	spa = spa_add(pool, altroot);
2147 	spa_activate(spa, spa_mode_global);
2148 
2149 	spa->spa_uberblock.ub_txg = txg - 1;
2150 
2151 	if (props && (error = spa_prop_validate(spa, props))) {
2152 		spa_deactivate(spa);
2153 		spa_remove(spa);
2154 		mutex_exit(&spa_namespace_lock);
2155 		return (error);
2156 	}
2157 
2158 	if (nvlist_lookup_uint64(props, zpool_prop_to_name(ZPOOL_PROP_VERSION),
2159 	    &version) != 0)
2160 		version = SPA_VERSION;
2161 	ASSERT(version <= SPA_VERSION);
2162 	spa->spa_uberblock.ub_version = version;
2163 	spa->spa_ubsync = spa->spa_uberblock;
2164 
2165 	/*
2166 	 * Create "The Godfather" zio to hold all async IOs
2167 	 */
2168 	spa->spa_async_zio_root = zio_root(spa, NULL, NULL,
2169 	    ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_GODFATHER);
2170 
2171 	/*
2172 	 * Create the root vdev.
2173 	 */
2174 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2175 
2176 	error = spa_config_parse(spa, &rvd, nvroot, NULL, 0, VDEV_ALLOC_ADD);
2177 
2178 	ASSERT(error != 0 || rvd != NULL);
2179 	ASSERT(error != 0 || spa->spa_root_vdev == rvd);
2180 
2181 	if (error == 0 && !zfs_allocatable_devs(nvroot))
2182 		error = EINVAL;
2183 
2184 	if (error == 0 &&
2185 	    (error = vdev_create(rvd, txg, B_FALSE)) == 0 &&
2186 	    (error = spa_validate_aux(spa, nvroot, txg,
2187 	    VDEV_ALLOC_ADD)) == 0) {
2188 		for (int c = 0; c < rvd->vdev_children; c++) {
2189 			vdev_metaslab_set_size(rvd->vdev_child[c]);
2190 			vdev_expand(rvd->vdev_child[c], txg);
2191 		}
2192 	}
2193 
2194 	spa_config_exit(spa, SCL_ALL, FTAG);
2195 
2196 	if (error != 0) {
2197 		spa_unload(spa);
2198 		spa_deactivate(spa);
2199 		spa_remove(spa);
2200 		mutex_exit(&spa_namespace_lock);
2201 		return (error);
2202 	}
2203 
2204 	/*
2205 	 * Get the list of spares, if specified.
2206 	 */
2207 	if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
2208 	    &spares, &nspares) == 0) {
2209 		VERIFY(nvlist_alloc(&spa->spa_spares.sav_config, NV_UNIQUE_NAME,
2210 		    KM_SLEEP) == 0);
2211 		VERIFY(nvlist_add_nvlist_array(spa->spa_spares.sav_config,
2212 		    ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
2213 		spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2214 		spa_load_spares(spa);
2215 		spa_config_exit(spa, SCL_ALL, FTAG);
2216 		spa->spa_spares.sav_sync = B_TRUE;
2217 	}
2218 
2219 	/*
2220 	 * Get the list of level 2 cache devices, if specified.
2221 	 */
2222 	if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
2223 	    &l2cache, &nl2cache) == 0) {
2224 		VERIFY(nvlist_alloc(&spa->spa_l2cache.sav_config,
2225 		    NV_UNIQUE_NAME, KM_SLEEP) == 0);
2226 		VERIFY(nvlist_add_nvlist_array(spa->spa_l2cache.sav_config,
2227 		    ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
2228 		spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2229 		spa_load_l2cache(spa);
2230 		spa_config_exit(spa, SCL_ALL, FTAG);
2231 		spa->spa_l2cache.sav_sync = B_TRUE;
2232 	}
2233 
2234 	spa->spa_dsl_pool = dp = dsl_pool_create(spa, zplprops, txg);
2235 	spa->spa_meta_objset = dp->dp_meta_objset;
2236 
2237 	tx = dmu_tx_create_assigned(dp, txg);
2238 
2239 	/*
2240 	 * Create the pool config object.
2241 	 */
2242 	spa->spa_config_object = dmu_object_alloc(spa->spa_meta_objset,
2243 	    DMU_OT_PACKED_NVLIST, SPA_CONFIG_BLOCKSIZE,
2244 	    DMU_OT_PACKED_NVLIST_SIZE, sizeof (uint64_t), tx);
2245 
2246 	if (zap_add(spa->spa_meta_objset,
2247 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_CONFIG,
2248 	    sizeof (uint64_t), 1, &spa->spa_config_object, tx) != 0) {
2249 		cmn_err(CE_PANIC, "failed to add pool config");
2250 	}
2251 
2252 	/* Newly created pools with the right version are always deflated. */
2253 	if (version >= SPA_VERSION_RAIDZ_DEFLATE) {
2254 		spa->spa_deflate = TRUE;
2255 		if (zap_add(spa->spa_meta_objset,
2256 		    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_DEFLATE,
2257 		    sizeof (uint64_t), 1, &spa->spa_deflate, tx) != 0) {
2258 			cmn_err(CE_PANIC, "failed to add deflate");
2259 		}
2260 	}
2261 
2262 	/*
2263 	 * Create the deferred-free bplist object.  Turn off compression
2264 	 * because sync-to-convergence takes longer if the blocksize
2265 	 * keeps changing.
2266 	 */
2267 	spa->spa_sync_bplist_obj = bplist_create(spa->spa_meta_objset,
2268 	    1 << 14, tx);
2269 	dmu_object_set_compress(spa->spa_meta_objset, spa->spa_sync_bplist_obj,
2270 	    ZIO_COMPRESS_OFF, tx);
2271 
2272 	if (zap_add(spa->spa_meta_objset,
2273 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_SYNC_BPLIST,
2274 	    sizeof (uint64_t), 1, &spa->spa_sync_bplist_obj, tx) != 0) {
2275 		cmn_err(CE_PANIC, "failed to add bplist");
2276 	}
2277 
2278 	/*
2279 	 * Create the pool's history object.
2280 	 */
2281 	if (version >= SPA_VERSION_ZPOOL_HISTORY)
2282 		spa_history_create_obj(spa, tx);
2283 
2284 	/*
2285 	 * Set pool properties.
2286 	 */
2287 	spa->spa_bootfs = zpool_prop_default_numeric(ZPOOL_PROP_BOOTFS);
2288 	spa->spa_delegation = zpool_prop_default_numeric(ZPOOL_PROP_DELEGATION);
2289 	spa->spa_failmode = zpool_prop_default_numeric(ZPOOL_PROP_FAILUREMODE);
2290 	spa->spa_autoexpand = zpool_prop_default_numeric(ZPOOL_PROP_AUTOEXPAND);
2291 	if (props != NULL) {
2292 		spa_configfile_set(spa, props, B_FALSE);
2293 		spa_sync_props(spa, props, CRED(), tx);
2294 	}
2295 
2296 	dmu_tx_commit(tx);
2297 
2298 	spa->spa_sync_on = B_TRUE;
2299 	txg_sync_start(spa->spa_dsl_pool);
2300 
2301 	/*
2302 	 * We explicitly wait for the first transaction to complete so that our
2303 	 * bean counters are appropriately updated.
2304 	 */
2305 	txg_wait_synced(spa->spa_dsl_pool, txg);
2306 
2307 	spa_config_sync(spa, B_FALSE, B_TRUE);
2308 
2309 	if (version >= SPA_VERSION_ZPOOL_HISTORY && history_str != NULL)
2310 		(void) spa_history_log(spa, history_str, LOG_CMD_POOL_CREATE);
2311 	spa_history_log_version(spa, LOG_POOL_CREATE);
2312 
2313 	spa->spa_minref = refcount_count(&spa->spa_refcount);
2314 
2315 	mutex_exit(&spa_namespace_lock);
2316 
2317 	return (0);
2318 }
2319 
2320 #ifdef _KERNEL
2321 /*
2322  * Get the root pool information from the root disk, then import the root pool
2323  * during the system boot up time.
2324  */
2325 extern int vdev_disk_read_rootlabel(char *, char *, nvlist_t **);
2326 
2327 static nvlist_t *
2328 spa_generate_rootconf(char *devpath, char *devid, uint64_t *guid)
2329 {
2330 	nvlist_t *config;
2331 	nvlist_t *nvtop, *nvroot;
2332 	uint64_t pgid;
2333 
2334 	if (vdev_disk_read_rootlabel(devpath, devid, &config) != 0)
2335 		return (NULL);
2336 
2337 	/*
2338 	 * Add this top-level vdev to the child array.
2339 	 */
2340 	VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
2341 	    &nvtop) == 0);
2342 	VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
2343 	    &pgid) == 0);
2344 	VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID, guid) == 0);
2345 
2346 	/*
2347 	 * Put this pool's top-level vdevs into a root vdev.
2348 	 */
2349 	VERIFY(nvlist_alloc(&nvroot, NV_UNIQUE_NAME, KM_SLEEP) == 0);
2350 	VERIFY(nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
2351 	    VDEV_TYPE_ROOT) == 0);
2352 	VERIFY(nvlist_add_uint64(nvroot, ZPOOL_CONFIG_ID, 0ULL) == 0);
2353 	VERIFY(nvlist_add_uint64(nvroot, ZPOOL_CONFIG_GUID, pgid) == 0);
2354 	VERIFY(nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
2355 	    &nvtop, 1) == 0);
2356 
2357 	/*
2358 	 * Replace the existing vdev_tree with the new root vdev in
2359 	 * this pool's configuration (remove the old, add the new).
2360 	 */
2361 	VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0);
2362 	nvlist_free(nvroot);
2363 	return (config);
2364 }
2365 
2366 /*
2367  * Walk the vdev tree and see if we can find a device with "better"
2368  * configuration. A configuration is "better" if the label on that
2369  * device has a more recent txg.
2370  */
2371 static void
2372 spa_alt_rootvdev(vdev_t *vd, vdev_t **avd, uint64_t *txg)
2373 {
2374 	for (int c = 0; c < vd->vdev_children; c++)
2375 		spa_alt_rootvdev(vd->vdev_child[c], avd, txg);
2376 
2377 	if (vd->vdev_ops->vdev_op_leaf) {
2378 		nvlist_t *label;
2379 		uint64_t label_txg;
2380 
2381 		if (vdev_disk_read_rootlabel(vd->vdev_physpath, vd->vdev_devid,
2382 		    &label) != 0)
2383 			return;
2384 
2385 		VERIFY(nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG,
2386 		    &label_txg) == 0);
2387 
2388 		/*
2389 		 * Do we have a better boot device?
2390 		 */
2391 		if (label_txg > *txg) {
2392 			*txg = label_txg;
2393 			*avd = vd;
2394 		}
2395 		nvlist_free(label);
2396 	}
2397 }
2398 
2399 /*
2400  * Import a root pool.
2401  *
2402  * For x86. devpath_list will consist of devid and/or physpath name of
2403  * the vdev (e.g. "id1,sd@SSEAGATE..." or "/pci@1f,0/ide@d/disk@0,0:a").
2404  * The GRUB "findroot" command will return the vdev we should boot.
2405  *
2406  * For Sparc, devpath_list consists the physpath name of the booting device
2407  * no matter the rootpool is a single device pool or a mirrored pool.
2408  * e.g.
2409  *	"/pci@1f,0/ide@d/disk@0,0:a"
2410  */
2411 int
2412 spa_import_rootpool(char *devpath, char *devid)
2413 {
2414 	spa_t *spa;
2415 	vdev_t *rvd, *bvd, *avd = NULL;
2416 	nvlist_t *config, *nvtop;
2417 	uint64_t guid, txg;
2418 	char *pname;
2419 	int error;
2420 
2421 	/*
2422 	 * Read the label from the boot device and generate a configuration.
2423 	 */
2424 	config = spa_generate_rootconf(devpath, devid, &guid);
2425 #if defined(_OBP) && defined(_KERNEL)
2426 	if (config == NULL) {
2427 		if (strstr(devpath, "/iscsi/ssd") != NULL) {
2428 			/* iscsi boot */
2429 			get_iscsi_bootpath_phy(devpath);
2430 			config = spa_generate_rootconf(devpath, devid, &guid);
2431 		}
2432 	}
2433 #endif
2434 	if (config == NULL) {
2435 		cmn_err(CE_NOTE, "Can not read the pool label from '%s'",
2436 		    devpath);
2437 		return (EIO);
2438 	}
2439 
2440 	VERIFY(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
2441 	    &pname) == 0);
2442 	VERIFY(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG, &txg) == 0);
2443 
2444 	mutex_enter(&spa_namespace_lock);
2445 	if ((spa = spa_lookup(pname)) != NULL) {
2446 		/*
2447 		 * Remove the existing root pool from the namespace so that we
2448 		 * can replace it with the correct config we just read in.
2449 		 */
2450 		spa_remove(spa);
2451 	}
2452 
2453 	spa = spa_add(pname, NULL);
2454 	spa->spa_is_root = B_TRUE;
2455 	spa->spa_load_verbatim = B_TRUE;
2456 
2457 	/*
2458 	 * Build up a vdev tree based on the boot device's label config.
2459 	 */
2460 	VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
2461 	    &nvtop) == 0);
2462 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2463 	error = spa_config_parse(spa, &rvd, nvtop, NULL, 0,
2464 	    VDEV_ALLOC_ROOTPOOL);
2465 	spa_config_exit(spa, SCL_ALL, FTAG);
2466 	if (error) {
2467 		mutex_exit(&spa_namespace_lock);
2468 		nvlist_free(config);
2469 		cmn_err(CE_NOTE, "Can not parse the config for pool '%s'",
2470 		    pname);
2471 		return (error);
2472 	}
2473 
2474 	/*
2475 	 * Get the boot vdev.
2476 	 */
2477 	if ((bvd = vdev_lookup_by_guid(rvd, guid)) == NULL) {
2478 		cmn_err(CE_NOTE, "Can not find the boot vdev for guid %llu",
2479 		    (u_longlong_t)guid);
2480 		error = ENOENT;
2481 		goto out;
2482 	}
2483 
2484 	/*
2485 	 * Determine if there is a better boot device.
2486 	 */
2487 	avd = bvd;
2488 	spa_alt_rootvdev(rvd, &avd, &txg);
2489 	if (avd != bvd) {
2490 		cmn_err(CE_NOTE, "The boot device is 'degraded'. Please "
2491 		    "try booting from '%s'", avd->vdev_path);
2492 		error = EINVAL;
2493 		goto out;
2494 	}
2495 
2496 	/*
2497 	 * If the boot device is part of a spare vdev then ensure that
2498 	 * we're booting off the active spare.
2499 	 */
2500 	if (bvd->vdev_parent->vdev_ops == &vdev_spare_ops &&
2501 	    !bvd->vdev_isspare) {
2502 		cmn_err(CE_NOTE, "The boot device is currently spared. Please "
2503 		    "try booting from '%s'",
2504 		    bvd->vdev_parent->vdev_child[1]->vdev_path);
2505 		error = EINVAL;
2506 		goto out;
2507 	}
2508 
2509 	VERIFY(nvlist_dup(config, &spa->spa_config, 0) == 0);
2510 	error = 0;
2511 	spa_history_log_version(spa, LOG_POOL_IMPORT);
2512 out:
2513 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2514 	vdev_free(rvd);
2515 	spa_config_exit(spa, SCL_ALL, FTAG);
2516 	mutex_exit(&spa_namespace_lock);
2517 
2518 	nvlist_free(config);
2519 	return (error);
2520 }
2521 
2522 #endif
2523 
2524 /*
2525  * Take a pool and insert it into the namespace as if it had been loaded at
2526  * boot.
2527  */
2528 int
2529 spa_import_verbatim(const char *pool, nvlist_t *config, nvlist_t *props)
2530 {
2531 	spa_t *spa;
2532 	char *altroot = NULL;
2533 
2534 	mutex_enter(&spa_namespace_lock);
2535 	if (spa_lookup(pool) != NULL) {
2536 		mutex_exit(&spa_namespace_lock);
2537 		return (EEXIST);
2538 	}
2539 
2540 	(void) nvlist_lookup_string(props,
2541 	    zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
2542 	spa = spa_add(pool, altroot);
2543 
2544 	spa->spa_load_verbatim = B_TRUE;
2545 
2546 	VERIFY(nvlist_dup(config, &spa->spa_config, 0) == 0);
2547 
2548 	if (props != NULL)
2549 		spa_configfile_set(spa, props, B_FALSE);
2550 
2551 	spa_config_sync(spa, B_FALSE, B_TRUE);
2552 
2553 	mutex_exit(&spa_namespace_lock);
2554 	spa_history_log_version(spa, LOG_POOL_IMPORT);
2555 
2556 	return (0);
2557 }
2558 
2559 /*
2560  * Import a non-root pool into the system.
2561  */
2562 int
2563 spa_import(const char *pool, nvlist_t *config, nvlist_t *props)
2564 {
2565 	spa_t *spa;
2566 	char *altroot = NULL;
2567 	int error;
2568 	nvlist_t *nvroot;
2569 	nvlist_t **spares, **l2cache;
2570 	uint_t nspares, nl2cache;
2571 
2572 	/*
2573 	 * If a pool with this name exists, return failure.
2574 	 */
2575 	mutex_enter(&spa_namespace_lock);
2576 	if ((spa = spa_lookup(pool)) != NULL) {
2577 		mutex_exit(&spa_namespace_lock);
2578 		return (EEXIST);
2579 	}
2580 
2581 	/*
2582 	 * Create and initialize the spa structure.
2583 	 */
2584 	(void) nvlist_lookup_string(props,
2585 	    zpool_prop_to_name(ZPOOL_PROP_ALTROOT), &altroot);
2586 	spa = spa_add(pool, altroot);
2587 	spa_activate(spa, spa_mode_global);
2588 
2589 	/*
2590 	 * Don't start async tasks until we know everything is healthy.
2591 	 */
2592 	spa_async_suspend(spa);
2593 
2594 	/*
2595 	 * Pass off the heavy lifting to spa_load().  Pass TRUE for mosconfig
2596 	 * because the user-supplied config is actually the one to trust when
2597 	 * doing an import.
2598 	 */
2599 	error = spa_load(spa, config, SPA_LOAD_IMPORT, B_TRUE);
2600 
2601 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2602 	/*
2603 	 * Toss any existing sparelist, as it doesn't have any validity
2604 	 * anymore, and conflicts with spa_has_spare().
2605 	 */
2606 	if (spa->spa_spares.sav_config) {
2607 		nvlist_free(spa->spa_spares.sav_config);
2608 		spa->spa_spares.sav_config = NULL;
2609 		spa_load_spares(spa);
2610 	}
2611 	if (spa->spa_l2cache.sav_config) {
2612 		nvlist_free(spa->spa_l2cache.sav_config);
2613 		spa->spa_l2cache.sav_config = NULL;
2614 		spa_load_l2cache(spa);
2615 	}
2616 
2617 	VERIFY(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
2618 	    &nvroot) == 0);
2619 	if (error == 0)
2620 		error = spa_validate_aux(spa, nvroot, -1ULL,
2621 		    VDEV_ALLOC_SPARE);
2622 	if (error == 0)
2623 		error = spa_validate_aux(spa, nvroot, -1ULL,
2624 		    VDEV_ALLOC_L2CACHE);
2625 	spa_config_exit(spa, SCL_ALL, FTAG);
2626 
2627 	if (props != NULL)
2628 		spa_configfile_set(spa, props, B_FALSE);
2629 
2630 	if (error != 0 || (props && spa_writeable(spa) &&
2631 	    (error = spa_prop_set(spa, props)))) {
2632 		spa_unload(spa);
2633 		spa_deactivate(spa);
2634 		spa_remove(spa);
2635 		mutex_exit(&spa_namespace_lock);
2636 		return (error);
2637 	}
2638 
2639 	spa_async_resume(spa);
2640 
2641 	/*
2642 	 * Override any spares and level 2 cache devices as specified by
2643 	 * the user, as these may have correct device names/devids, etc.
2644 	 */
2645 	if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
2646 	    &spares, &nspares) == 0) {
2647 		if (spa->spa_spares.sav_config)
2648 			VERIFY(nvlist_remove(spa->spa_spares.sav_config,
2649 			    ZPOOL_CONFIG_SPARES, DATA_TYPE_NVLIST_ARRAY) == 0);
2650 		else
2651 			VERIFY(nvlist_alloc(&spa->spa_spares.sav_config,
2652 			    NV_UNIQUE_NAME, KM_SLEEP) == 0);
2653 		VERIFY(nvlist_add_nvlist_array(spa->spa_spares.sav_config,
2654 		    ZPOOL_CONFIG_SPARES, spares, nspares) == 0);
2655 		spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2656 		spa_load_spares(spa);
2657 		spa_config_exit(spa, SCL_ALL, FTAG);
2658 		spa->spa_spares.sav_sync = B_TRUE;
2659 	}
2660 	if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
2661 	    &l2cache, &nl2cache) == 0) {
2662 		if (spa->spa_l2cache.sav_config)
2663 			VERIFY(nvlist_remove(spa->spa_l2cache.sav_config,
2664 			    ZPOOL_CONFIG_L2CACHE, DATA_TYPE_NVLIST_ARRAY) == 0);
2665 		else
2666 			VERIFY(nvlist_alloc(&spa->spa_l2cache.sav_config,
2667 			    NV_UNIQUE_NAME, KM_SLEEP) == 0);
2668 		VERIFY(nvlist_add_nvlist_array(spa->spa_l2cache.sav_config,
2669 		    ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache) == 0);
2670 		spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2671 		spa_load_l2cache(spa);
2672 		spa_config_exit(spa, SCL_ALL, FTAG);
2673 		spa->spa_l2cache.sav_sync = B_TRUE;
2674 	}
2675 
2676 	/*
2677 	 * Check for any removed devices.
2678 	 */
2679 	if (spa->spa_autoreplace) {
2680 		spa_aux_check_removed(&spa->spa_spares);
2681 		spa_aux_check_removed(&spa->spa_l2cache);
2682 	}
2683 
2684 	if (spa_writeable(spa)) {
2685 		/*
2686 		 * Update the config cache to include the newly-imported pool.
2687 		 */
2688 		spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
2689 	}
2690 
2691 	/*
2692 	 * It's possible that the pool was expanded while it was exported.
2693 	 * We kick off an async task to handle this for us.
2694 	 */
2695 	spa_async_request(spa, SPA_ASYNC_AUTOEXPAND);
2696 
2697 	mutex_exit(&spa_namespace_lock);
2698 	spa_history_log_version(spa, LOG_POOL_IMPORT);
2699 
2700 	return (0);
2701 }
2702 
2703 
2704 /*
2705  * This (illegal) pool name is used when temporarily importing a spa_t in order
2706  * to get the vdev stats associated with the imported devices.
2707  */
2708 #define	TRYIMPORT_NAME	"$import"
2709 
2710 nvlist_t *
2711 spa_tryimport(nvlist_t *tryconfig)
2712 {
2713 	nvlist_t *config = NULL;
2714 	char *poolname;
2715 	spa_t *spa;
2716 	uint64_t state;
2717 	int error;
2718 
2719 	if (nvlist_lookup_string(tryconfig, ZPOOL_CONFIG_POOL_NAME, &poolname))
2720 		return (NULL);
2721 
2722 	if (nvlist_lookup_uint64(tryconfig, ZPOOL_CONFIG_POOL_STATE, &state))
2723 		return (NULL);
2724 
2725 	/*
2726 	 * Create and initialize the spa structure.
2727 	 */
2728 	mutex_enter(&spa_namespace_lock);
2729 	spa = spa_add(TRYIMPORT_NAME, NULL);
2730 	spa_activate(spa, FREAD);
2731 
2732 	/*
2733 	 * Pass off the heavy lifting to spa_load().
2734 	 * Pass TRUE for mosconfig because the user-supplied config
2735 	 * is actually the one to trust when doing an import.
2736 	 */
2737 	error = spa_load(spa, tryconfig, SPA_LOAD_TRYIMPORT, B_TRUE);
2738 
2739 	/*
2740 	 * If 'tryconfig' was at least parsable, return the current config.
2741 	 */
2742 	if (spa->spa_root_vdev != NULL) {
2743 		config = spa_config_generate(spa, NULL, -1ULL, B_TRUE);
2744 		VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME,
2745 		    poolname) == 0);
2746 		VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
2747 		    state) == 0);
2748 		VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TIMESTAMP,
2749 		    spa->spa_uberblock.ub_timestamp) == 0);
2750 
2751 		/*
2752 		 * If the bootfs property exists on this pool then we
2753 		 * copy it out so that external consumers can tell which
2754 		 * pools are bootable.
2755 		 */
2756 		if ((!error || error == EEXIST) && spa->spa_bootfs) {
2757 			char *tmpname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
2758 
2759 			/*
2760 			 * We have to play games with the name since the
2761 			 * pool was opened as TRYIMPORT_NAME.
2762 			 */
2763 			if (dsl_dsobj_to_dsname(spa_name(spa),
2764 			    spa->spa_bootfs, tmpname) == 0) {
2765 				char *cp;
2766 				char *dsname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
2767 
2768 				cp = strchr(tmpname, '/');
2769 				if (cp == NULL) {
2770 					(void) strlcpy(dsname, tmpname,
2771 					    MAXPATHLEN);
2772 				} else {
2773 					(void) snprintf(dsname, MAXPATHLEN,
2774 					    "%s/%s", poolname, ++cp);
2775 				}
2776 				VERIFY(nvlist_add_string(config,
2777 				    ZPOOL_CONFIG_BOOTFS, dsname) == 0);
2778 				kmem_free(dsname, MAXPATHLEN);
2779 			}
2780 			kmem_free(tmpname, MAXPATHLEN);
2781 		}
2782 
2783 		/*
2784 		 * Add the list of hot spares and level 2 cache devices.
2785 		 */
2786 		spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
2787 		spa_add_spares(spa, config);
2788 		spa_add_l2cache(spa, config);
2789 		spa_config_exit(spa, SCL_CONFIG, FTAG);
2790 	}
2791 
2792 	spa_unload(spa);
2793 	spa_deactivate(spa);
2794 	spa_remove(spa);
2795 	mutex_exit(&spa_namespace_lock);
2796 
2797 	return (config);
2798 }
2799 
2800 /*
2801  * Pool export/destroy
2802  *
2803  * The act of destroying or exporting a pool is very simple.  We make sure there
2804  * is no more pending I/O and any references to the pool are gone.  Then, we
2805  * update the pool state and sync all the labels to disk, removing the
2806  * configuration from the cache afterwards. If the 'hardforce' flag is set, then
2807  * we don't sync the labels or remove the configuration cache.
2808  */
2809 static int
2810 spa_export_common(char *pool, int new_state, nvlist_t **oldconfig,
2811     boolean_t force, boolean_t hardforce)
2812 {
2813 	spa_t *spa;
2814 
2815 	if (oldconfig)
2816 		*oldconfig = NULL;
2817 
2818 	if (!(spa_mode_global & FWRITE))
2819 		return (EROFS);
2820 
2821 	mutex_enter(&spa_namespace_lock);
2822 	if ((spa = spa_lookup(pool)) == NULL) {
2823 		mutex_exit(&spa_namespace_lock);
2824 		return (ENOENT);
2825 	}
2826 
2827 	/*
2828 	 * Put a hold on the pool, drop the namespace lock, stop async tasks,
2829 	 * reacquire the namespace lock, and see if we can export.
2830 	 */
2831 	spa_open_ref(spa, FTAG);
2832 	mutex_exit(&spa_namespace_lock);
2833 	spa_async_suspend(spa);
2834 	mutex_enter(&spa_namespace_lock);
2835 	spa_close(spa, FTAG);
2836 
2837 	/*
2838 	 * The pool will be in core if it's openable,
2839 	 * in which case we can modify its state.
2840 	 */
2841 	if (spa->spa_state != POOL_STATE_UNINITIALIZED && spa->spa_sync_on) {
2842 		/*
2843 		 * Objsets may be open only because they're dirty, so we
2844 		 * have to force it to sync before checking spa_refcnt.
2845 		 */
2846 		txg_wait_synced(spa->spa_dsl_pool, 0);
2847 
2848 		/*
2849 		 * A pool cannot be exported or destroyed if there are active
2850 		 * references.  If we are resetting a pool, allow references by
2851 		 * fault injection handlers.
2852 		 */
2853 		if (!spa_refcount_zero(spa) ||
2854 		    (spa->spa_inject_ref != 0 &&
2855 		    new_state != POOL_STATE_UNINITIALIZED)) {
2856 			spa_async_resume(spa);
2857 			mutex_exit(&spa_namespace_lock);
2858 			return (EBUSY);
2859 		}
2860 
2861 		/*
2862 		 * A pool cannot be exported if it has an active shared spare.
2863 		 * This is to prevent other pools stealing the active spare
2864 		 * from an exported pool. At user's own will, such pool can
2865 		 * be forcedly exported.
2866 		 */
2867 		if (!force && new_state == POOL_STATE_EXPORTED &&
2868 		    spa_has_active_shared_spare(spa)) {
2869 			spa_async_resume(spa);
2870 			mutex_exit(&spa_namespace_lock);
2871 			return (EXDEV);
2872 		}
2873 
2874 		/*
2875 		 * We want this to be reflected on every label,
2876 		 * so mark them all dirty.  spa_unload() will do the
2877 		 * final sync that pushes these changes out.
2878 		 */
2879 		if (new_state != POOL_STATE_UNINITIALIZED && !hardforce) {
2880 			spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
2881 			spa->spa_state = new_state;
2882 			spa->spa_final_txg = spa_last_synced_txg(spa) + 1;
2883 			vdev_config_dirty(spa->spa_root_vdev);
2884 			spa_config_exit(spa, SCL_ALL, FTAG);
2885 		}
2886 	}
2887 
2888 	spa_event_notify(spa, NULL, ESC_ZFS_POOL_DESTROY);
2889 
2890 	if (spa->spa_state != POOL_STATE_UNINITIALIZED) {
2891 		spa_unload(spa);
2892 		spa_deactivate(spa);
2893 	}
2894 
2895 	if (oldconfig && spa->spa_config)
2896 		VERIFY(nvlist_dup(spa->spa_config, oldconfig, 0) == 0);
2897 
2898 	if (new_state != POOL_STATE_UNINITIALIZED) {
2899 		if (!hardforce)
2900 			spa_config_sync(spa, B_TRUE, B_TRUE);
2901 		spa_remove(spa);
2902 	}
2903 	mutex_exit(&spa_namespace_lock);
2904 
2905 	return (0);
2906 }
2907 
2908 /*
2909  * Destroy a storage pool.
2910  */
2911 int
2912 spa_destroy(char *pool)
2913 {
2914 	return (spa_export_common(pool, POOL_STATE_DESTROYED, NULL,
2915 	    B_FALSE, B_FALSE));
2916 }
2917 
2918 /*
2919  * Export a storage pool.
2920  */
2921 int
2922 spa_export(char *pool, nvlist_t **oldconfig, boolean_t force,
2923     boolean_t hardforce)
2924 {
2925 	return (spa_export_common(pool, POOL_STATE_EXPORTED, oldconfig,
2926 	    force, hardforce));
2927 }
2928 
2929 /*
2930  * Similar to spa_export(), this unloads the spa_t without actually removing it
2931  * from the namespace in any way.
2932  */
2933 int
2934 spa_reset(char *pool)
2935 {
2936 	return (spa_export_common(pool, POOL_STATE_UNINITIALIZED, NULL,
2937 	    B_FALSE, B_FALSE));
2938 }
2939 
2940 /*
2941  * ==========================================================================
2942  * Device manipulation
2943  * ==========================================================================
2944  */
2945 
2946 /*
2947  * Add a device to a storage pool.
2948  */
2949 int
2950 spa_vdev_add(spa_t *spa, nvlist_t *nvroot)
2951 {
2952 	uint64_t txg, id;
2953 	int error;
2954 	vdev_t *rvd = spa->spa_root_vdev;
2955 	vdev_t *vd, *tvd;
2956 	nvlist_t **spares, **l2cache;
2957 	uint_t nspares, nl2cache;
2958 
2959 	txg = spa_vdev_enter(spa);
2960 
2961 	if ((error = spa_config_parse(spa, &vd, nvroot, NULL, 0,
2962 	    VDEV_ALLOC_ADD)) != 0)
2963 		return (spa_vdev_exit(spa, NULL, txg, error));
2964 
2965 	spa->spa_pending_vdev = vd;	/* spa_vdev_exit() will clear this */
2966 
2967 	if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES, &spares,
2968 	    &nspares) != 0)
2969 		nspares = 0;
2970 
2971 	if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE, &l2cache,
2972 	    &nl2cache) != 0)
2973 		nl2cache = 0;
2974 
2975 	if (vd->vdev_children == 0 && nspares == 0 && nl2cache == 0)
2976 		return (spa_vdev_exit(spa, vd, txg, EINVAL));
2977 
2978 	if (vd->vdev_children != 0 &&
2979 	    (error = vdev_create(vd, txg, B_FALSE)) != 0)
2980 		return (spa_vdev_exit(spa, vd, txg, error));
2981 
2982 	/*
2983 	 * We must validate the spares and l2cache devices after checking the
2984 	 * children.  Otherwise, vdev_inuse() will blindly overwrite the spare.
2985 	 */
2986 	if ((error = spa_validate_aux(spa, nvroot, txg, VDEV_ALLOC_ADD)) != 0)
2987 		return (spa_vdev_exit(spa, vd, txg, error));
2988 
2989 	/*
2990 	 * Transfer each new top-level vdev from vd to rvd.
2991 	 */
2992 	for (int c = 0; c < vd->vdev_children; c++) {
2993 
2994 		/*
2995 		 * Set the vdev id to the first hole, if one exists.
2996 		 */
2997 		for (id = 0; id < rvd->vdev_children; id++) {
2998 			if (rvd->vdev_child[id]->vdev_ishole) {
2999 				vdev_free(rvd->vdev_child[id]);
3000 				break;
3001 			}
3002 		}
3003 		tvd = vd->vdev_child[c];
3004 		vdev_remove_child(vd, tvd);
3005 		tvd->vdev_id = id;
3006 		vdev_add_child(rvd, tvd);
3007 		vdev_config_dirty(tvd);
3008 	}
3009 
3010 	if (nspares != 0) {
3011 		spa_set_aux_vdevs(&spa->spa_spares, spares, nspares,
3012 		    ZPOOL_CONFIG_SPARES);
3013 		spa_load_spares(spa);
3014 		spa->spa_spares.sav_sync = B_TRUE;
3015 	}
3016 
3017 	if (nl2cache != 0) {
3018 		spa_set_aux_vdevs(&spa->spa_l2cache, l2cache, nl2cache,
3019 		    ZPOOL_CONFIG_L2CACHE);
3020 		spa_load_l2cache(spa);
3021 		spa->spa_l2cache.sav_sync = B_TRUE;
3022 	}
3023 
3024 	/*
3025 	 * We have to be careful when adding new vdevs to an existing pool.
3026 	 * If other threads start allocating from these vdevs before we
3027 	 * sync the config cache, and we lose power, then upon reboot we may
3028 	 * fail to open the pool because there are DVAs that the config cache
3029 	 * can't translate.  Therefore, we first add the vdevs without
3030 	 * initializing metaslabs; sync the config cache (via spa_vdev_exit());
3031 	 * and then let spa_config_update() initialize the new metaslabs.
3032 	 *
3033 	 * spa_load() checks for added-but-not-initialized vdevs, so that
3034 	 * if we lose power at any point in this sequence, the remaining
3035 	 * steps will be completed the next time we load the pool.
3036 	 */
3037 	(void) spa_vdev_exit(spa, vd, txg, 0);
3038 
3039 	mutex_enter(&spa_namespace_lock);
3040 	spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
3041 	mutex_exit(&spa_namespace_lock);
3042 
3043 	return (0);
3044 }
3045 
3046 /*
3047  * Attach a device to a mirror.  The arguments are the path to any device
3048  * in the mirror, and the nvroot for the new device.  If the path specifies
3049  * a device that is not mirrored, we automatically insert the mirror vdev.
3050  *
3051  * If 'replacing' is specified, the new device is intended to replace the
3052  * existing device; in this case the two devices are made into their own
3053  * mirror using the 'replacing' vdev, which is functionally identical to
3054  * the mirror vdev (it actually reuses all the same ops) but has a few
3055  * extra rules: you can't attach to it after it's been created, and upon
3056  * completion of resilvering, the first disk (the one being replaced)
3057  * is automatically detached.
3058  */
3059 int
3060 spa_vdev_attach(spa_t *spa, uint64_t guid, nvlist_t *nvroot, int replacing)
3061 {
3062 	uint64_t txg, open_txg;
3063 	vdev_t *rvd = spa->spa_root_vdev;
3064 	vdev_t *oldvd, *newvd, *newrootvd, *pvd, *tvd;
3065 	vdev_ops_t *pvops;
3066 	char *oldvdpath, *newvdpath;
3067 	int newvd_isspare;
3068 	int error;
3069 
3070 	txg = spa_vdev_enter(spa);
3071 
3072 	oldvd = spa_lookup_by_guid(spa, guid, B_FALSE);
3073 
3074 	if (oldvd == NULL)
3075 		return (spa_vdev_exit(spa, NULL, txg, ENODEV));
3076 
3077 	if (!oldvd->vdev_ops->vdev_op_leaf)
3078 		return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
3079 
3080 	pvd = oldvd->vdev_parent;
3081 
3082 	if ((error = spa_config_parse(spa, &newrootvd, nvroot, NULL, 0,
3083 	    VDEV_ALLOC_ADD)) != 0)
3084 		return (spa_vdev_exit(spa, NULL, txg, EINVAL));
3085 
3086 	if (newrootvd->vdev_children != 1)
3087 		return (spa_vdev_exit(spa, newrootvd, txg, EINVAL));
3088 
3089 	newvd = newrootvd->vdev_child[0];
3090 
3091 	if (!newvd->vdev_ops->vdev_op_leaf)
3092 		return (spa_vdev_exit(spa, newrootvd, txg, EINVAL));
3093 
3094 	if ((error = vdev_create(newrootvd, txg, replacing)) != 0)
3095 		return (spa_vdev_exit(spa, newrootvd, txg, error));
3096 
3097 	/*
3098 	 * Spares can't replace logs
3099 	 */
3100 	if (oldvd->vdev_top->vdev_islog && newvd->vdev_isspare)
3101 		return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
3102 
3103 	if (!replacing) {
3104 		/*
3105 		 * For attach, the only allowable parent is a mirror or the root
3106 		 * vdev.
3107 		 */
3108 		if (pvd->vdev_ops != &vdev_mirror_ops &&
3109 		    pvd->vdev_ops != &vdev_root_ops)
3110 			return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
3111 
3112 		pvops = &vdev_mirror_ops;
3113 	} else {
3114 		/*
3115 		 * Active hot spares can only be replaced by inactive hot
3116 		 * spares.
3117 		 */
3118 		if (pvd->vdev_ops == &vdev_spare_ops &&
3119 		    pvd->vdev_child[1] == oldvd &&
3120 		    !spa_has_spare(spa, newvd->vdev_guid))
3121 			return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
3122 
3123 		/*
3124 		 * If the source is a hot spare, and the parent isn't already a
3125 		 * spare, then we want to create a new hot spare.  Otherwise, we
3126 		 * want to create a replacing vdev.  The user is not allowed to
3127 		 * attach to a spared vdev child unless the 'isspare' state is
3128 		 * the same (spare replaces spare, non-spare replaces
3129 		 * non-spare).
3130 		 */
3131 		if (pvd->vdev_ops == &vdev_replacing_ops)
3132 			return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
3133 		else if (pvd->vdev_ops == &vdev_spare_ops &&
3134 		    newvd->vdev_isspare != oldvd->vdev_isspare)
3135 			return (spa_vdev_exit(spa, newrootvd, txg, ENOTSUP));
3136 		else if (pvd->vdev_ops != &vdev_spare_ops &&
3137 		    newvd->vdev_isspare)
3138 			pvops = &vdev_spare_ops;
3139 		else
3140 			pvops = &vdev_replacing_ops;
3141 	}
3142 
3143 	/*
3144 	 * Make sure the new device is big enough.
3145 	 */
3146 	if (newvd->vdev_asize < vdev_get_min_asize(oldvd))
3147 		return (spa_vdev_exit(spa, newrootvd, txg, EOVERFLOW));
3148 
3149 	/*
3150 	 * The new device cannot have a higher alignment requirement
3151 	 * than the top-level vdev.
3152 	 */
3153 	if (newvd->vdev_ashift > oldvd->vdev_top->vdev_ashift)
3154 		return (spa_vdev_exit(spa, newrootvd, txg, EDOM));
3155 
3156 	/*
3157 	 * If this is an in-place replacement, update oldvd's path and devid
3158 	 * to make it distinguishable from newvd, and unopenable from now on.
3159 	 */
3160 	if (strcmp(oldvd->vdev_path, newvd->vdev_path) == 0) {
3161 		spa_strfree(oldvd->vdev_path);
3162 		oldvd->vdev_path = kmem_alloc(strlen(newvd->vdev_path) + 5,
3163 		    KM_SLEEP);
3164 		(void) sprintf(oldvd->vdev_path, "%s/%s",
3165 		    newvd->vdev_path, "old");
3166 		if (oldvd->vdev_devid != NULL) {
3167 			spa_strfree(oldvd->vdev_devid);
3168 			oldvd->vdev_devid = NULL;
3169 		}
3170 	}
3171 
3172 	/*
3173 	 * If the parent is not a mirror, or if we're replacing, insert the new
3174 	 * mirror/replacing/spare vdev above oldvd.
3175 	 */
3176 	if (pvd->vdev_ops != pvops)
3177 		pvd = vdev_add_parent(oldvd, pvops);
3178 
3179 	ASSERT(pvd->vdev_top->vdev_parent == rvd);
3180 	ASSERT(pvd->vdev_ops == pvops);
3181 	ASSERT(oldvd->vdev_parent == pvd);
3182 
3183 	/*
3184 	 * Extract the new device from its root and add it to pvd.
3185 	 */
3186 	vdev_remove_child(newrootvd, newvd);
3187 	newvd->vdev_id = pvd->vdev_children;
3188 	newvd->vdev_crtxg = oldvd->vdev_crtxg;
3189 	vdev_add_child(pvd, newvd);
3190 
3191 	tvd = newvd->vdev_top;
3192 	ASSERT(pvd->vdev_top == tvd);
3193 	ASSERT(tvd->vdev_parent == rvd);
3194 
3195 	vdev_config_dirty(tvd);
3196 
3197 	/*
3198 	 * Set newvd's DTL to [TXG_INITIAL, open_txg].  It will propagate
3199 	 * upward when spa_vdev_exit() calls vdev_dtl_reassess().
3200 	 */
3201 	open_txg = txg + TXG_CONCURRENT_STATES - 1;
3202 
3203 	vdev_dtl_dirty(newvd, DTL_MISSING,
3204 	    TXG_INITIAL, open_txg - TXG_INITIAL + 1);
3205 
3206 	if (newvd->vdev_isspare) {
3207 		spa_spare_activate(newvd);
3208 		spa_event_notify(spa, newvd, ESC_ZFS_VDEV_SPARE);
3209 	}
3210 
3211 	oldvdpath = spa_strdup(oldvd->vdev_path);
3212 	newvdpath = spa_strdup(newvd->vdev_path);
3213 	newvd_isspare = newvd->vdev_isspare;
3214 
3215 	/*
3216 	 * Mark newvd's DTL dirty in this txg.
3217 	 */
3218 	vdev_dirty(tvd, VDD_DTL, newvd, txg);
3219 
3220 	(void) spa_vdev_exit(spa, newrootvd, open_txg, 0);
3221 
3222 	spa_history_internal_log(LOG_POOL_VDEV_ATTACH, spa, NULL,
3223 	    CRED(),  "%s vdev=%s %s vdev=%s",
3224 	    replacing && newvd_isspare ? "spare in" :
3225 	    replacing ? "replace" : "attach", newvdpath,
3226 	    replacing ? "for" : "to", oldvdpath);
3227 
3228 	spa_strfree(oldvdpath);
3229 	spa_strfree(newvdpath);
3230 
3231 	/*
3232 	 * Kick off a resilver to update newvd.
3233 	 */
3234 	VERIFY3U(spa_scrub(spa, POOL_SCRUB_RESILVER), ==, 0);
3235 
3236 	return (0);
3237 }
3238 
3239 /*
3240  * Detach a device from a mirror or replacing vdev.
3241  * If 'replace_done' is specified, only detach if the parent
3242  * is a replacing vdev.
3243  */
3244 int
3245 spa_vdev_detach(spa_t *spa, uint64_t guid, uint64_t pguid, int replace_done)
3246 {
3247 	uint64_t txg;
3248 	int error;
3249 	vdev_t *rvd = spa->spa_root_vdev;
3250 	vdev_t *vd, *pvd, *cvd, *tvd;
3251 	boolean_t unspare = B_FALSE;
3252 	uint64_t unspare_guid;
3253 	size_t len;
3254 
3255 	txg = spa_vdev_enter(spa);
3256 
3257 	vd = spa_lookup_by_guid(spa, guid, B_FALSE);
3258 
3259 	if (vd == NULL)
3260 		return (spa_vdev_exit(spa, NULL, txg, ENODEV));
3261 
3262 	if (!vd->vdev_ops->vdev_op_leaf)
3263 		return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
3264 
3265 	pvd = vd->vdev_parent;
3266 
3267 	/*
3268 	 * If the parent/child relationship is not as expected, don't do it.
3269 	 * Consider M(A,R(B,C)) -- that is, a mirror of A with a replacing
3270 	 * vdev that's replacing B with C.  The user's intent in replacing
3271 	 * is to go from M(A,B) to M(A,C).  If the user decides to cancel
3272 	 * the replace by detaching C, the expected behavior is to end up
3273 	 * M(A,B).  But suppose that right after deciding to detach C,
3274 	 * the replacement of B completes.  We would have M(A,C), and then
3275 	 * ask to detach C, which would leave us with just A -- not what
3276 	 * the user wanted.  To prevent this, we make sure that the
3277 	 * parent/child relationship hasn't changed -- in this example,
3278 	 * that C's parent is still the replacing vdev R.
3279 	 */
3280 	if (pvd->vdev_guid != pguid && pguid != 0)
3281 		return (spa_vdev_exit(spa, NULL, txg, EBUSY));
3282 
3283 	/*
3284 	 * If replace_done is specified, only remove this device if it's
3285 	 * the first child of a replacing vdev.  For the 'spare' vdev, either
3286 	 * disk can be removed.
3287 	 */
3288 	if (replace_done) {
3289 		if (pvd->vdev_ops == &vdev_replacing_ops) {
3290 			if (vd->vdev_id != 0)
3291 				return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
3292 		} else if (pvd->vdev_ops != &vdev_spare_ops) {
3293 			return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
3294 		}
3295 	}
3296 
3297 	ASSERT(pvd->vdev_ops != &vdev_spare_ops ||
3298 	    spa_version(spa) >= SPA_VERSION_SPARES);
3299 
3300 	/*
3301 	 * Only mirror, replacing, and spare vdevs support detach.
3302 	 */
3303 	if (pvd->vdev_ops != &vdev_replacing_ops &&
3304 	    pvd->vdev_ops != &vdev_mirror_ops &&
3305 	    pvd->vdev_ops != &vdev_spare_ops)
3306 		return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
3307 
3308 	/*
3309 	 * If this device has the only valid copy of some data,
3310 	 * we cannot safely detach it.
3311 	 */
3312 	if (vdev_dtl_required(vd))
3313 		return (spa_vdev_exit(spa, NULL, txg, EBUSY));
3314 
3315 	ASSERT(pvd->vdev_children >= 2);
3316 
3317 	/*
3318 	 * If we are detaching the second disk from a replacing vdev, then
3319 	 * check to see if we changed the original vdev's path to have "/old"
3320 	 * at the end in spa_vdev_attach().  If so, undo that change now.
3321 	 */
3322 	if (pvd->vdev_ops == &vdev_replacing_ops && vd->vdev_id == 1 &&
3323 	    pvd->vdev_child[0]->vdev_path != NULL &&
3324 	    pvd->vdev_child[1]->vdev_path != NULL) {
3325 		ASSERT(pvd->vdev_child[1] == vd);
3326 		cvd = pvd->vdev_child[0];
3327 		len = strlen(vd->vdev_path);
3328 		if (strncmp(cvd->vdev_path, vd->vdev_path, len) == 0 &&
3329 		    strcmp(cvd->vdev_path + len, "/old") == 0) {
3330 			spa_strfree(cvd->vdev_path);
3331 			cvd->vdev_path = spa_strdup(vd->vdev_path);
3332 		}
3333 	}
3334 
3335 	/*
3336 	 * If we are detaching the original disk from a spare, then it implies
3337 	 * that the spare should become a real disk, and be removed from the
3338 	 * active spare list for the pool.
3339 	 */
3340 	if (pvd->vdev_ops == &vdev_spare_ops &&
3341 	    vd->vdev_id == 0 && pvd->vdev_child[1]->vdev_isspare)
3342 		unspare = B_TRUE;
3343 
3344 	/*
3345 	 * Erase the disk labels so the disk can be used for other things.
3346 	 * This must be done after all other error cases are handled,
3347 	 * but before we disembowel vd (so we can still do I/O to it).
3348 	 * But if we can't do it, don't treat the error as fatal --
3349 	 * it may be that the unwritability of the disk is the reason
3350 	 * it's being detached!
3351 	 */
3352 	error = vdev_label_init(vd, 0, VDEV_LABEL_REMOVE);
3353 
3354 	/*
3355 	 * Remove vd from its parent and compact the parent's children.
3356 	 */
3357 	vdev_remove_child(pvd, vd);
3358 	vdev_compact_children(pvd);
3359 
3360 	/*
3361 	 * Remember one of the remaining children so we can get tvd below.
3362 	 */
3363 	cvd = pvd->vdev_child[0];
3364 
3365 	/*
3366 	 * If we need to remove the remaining child from the list of hot spares,
3367 	 * do it now, marking the vdev as no longer a spare in the process.
3368 	 * We must do this before vdev_remove_parent(), because that can
3369 	 * change the GUID if it creates a new toplevel GUID.  For a similar
3370 	 * reason, we must remove the spare now, in the same txg as the detach;
3371 	 * otherwise someone could attach a new sibling, change the GUID, and
3372 	 * the subsequent attempt to spa_vdev_remove(unspare_guid) would fail.
3373 	 */
3374 	if (unspare) {
3375 		ASSERT(cvd->vdev_isspare);
3376 		spa_spare_remove(cvd);
3377 		unspare_guid = cvd->vdev_guid;
3378 		(void) spa_vdev_remove(spa, unspare_guid, B_TRUE);
3379 	}
3380 
3381 	/*
3382 	 * If the parent mirror/replacing vdev only has one child,
3383 	 * the parent is no longer needed.  Remove it from the tree.
3384 	 */
3385 	if (pvd->vdev_children == 1)
3386 		vdev_remove_parent(cvd);
3387 
3388 	/*
3389 	 * We don't set tvd until now because the parent we just removed
3390 	 * may have been the previous top-level vdev.
3391 	 */
3392 	tvd = cvd->vdev_top;
3393 	ASSERT(tvd->vdev_parent == rvd);
3394 
3395 	/*
3396 	 * Reevaluate the parent vdev state.
3397 	 */
3398 	vdev_propagate_state(cvd);
3399 
3400 	/*
3401 	 * If the 'autoexpand' property is set on the pool then automatically
3402 	 * try to expand the size of the pool. For example if the device we
3403 	 * just detached was smaller than the others, it may be possible to
3404 	 * add metaslabs (i.e. grow the pool). We need to reopen the vdev
3405 	 * first so that we can obtain the updated sizes of the leaf vdevs.
3406 	 */
3407 	if (spa->spa_autoexpand) {
3408 		vdev_reopen(tvd);
3409 		vdev_expand(tvd, txg);
3410 	}
3411 
3412 	vdev_config_dirty(tvd);
3413 
3414 	/*
3415 	 * Mark vd's DTL as dirty in this txg.  vdev_dtl_sync() will see that
3416 	 * vd->vdev_detached is set and free vd's DTL object in syncing context.
3417 	 * But first make sure we're not on any *other* txg's DTL list, to
3418 	 * prevent vd from being accessed after it's freed.
3419 	 */
3420 	for (int t = 0; t < TXG_SIZE; t++)
3421 		(void) txg_list_remove_this(&tvd->vdev_dtl_list, vd, t);
3422 	vd->vdev_detached = B_TRUE;
3423 	vdev_dirty(tvd, VDD_DTL, vd, txg);
3424 
3425 	spa_event_notify(spa, vd, ESC_ZFS_VDEV_REMOVE);
3426 
3427 	error = spa_vdev_exit(spa, vd, txg, 0);
3428 
3429 	/*
3430 	 * If this was the removal of the original device in a hot spare vdev,
3431 	 * then we want to go through and remove the device from the hot spare
3432 	 * list of every other pool.
3433 	 */
3434 	if (unspare) {
3435 		spa_t *myspa = spa;
3436 		spa = NULL;
3437 		mutex_enter(&spa_namespace_lock);
3438 		while ((spa = spa_next(spa)) != NULL) {
3439 			if (spa->spa_state != POOL_STATE_ACTIVE)
3440 				continue;
3441 			if (spa == myspa)
3442 				continue;
3443 			spa_open_ref(spa, FTAG);
3444 			mutex_exit(&spa_namespace_lock);
3445 			(void) spa_vdev_remove(spa, unspare_guid, B_TRUE);
3446 			mutex_enter(&spa_namespace_lock);
3447 			spa_close(spa, FTAG);
3448 		}
3449 		mutex_exit(&spa_namespace_lock);
3450 	}
3451 
3452 	return (error);
3453 }
3454 
3455 static nvlist_t *
3456 spa_nvlist_lookup_by_guid(nvlist_t **nvpp, int count, uint64_t target_guid)
3457 {
3458 	for (int i = 0; i < count; i++) {
3459 		uint64_t guid;
3460 
3461 		VERIFY(nvlist_lookup_uint64(nvpp[i], ZPOOL_CONFIG_GUID,
3462 		    &guid) == 0);
3463 
3464 		if (guid == target_guid)
3465 			return (nvpp[i]);
3466 	}
3467 
3468 	return (NULL);
3469 }
3470 
3471 static void
3472 spa_vdev_remove_aux(nvlist_t *config, char *name, nvlist_t **dev, int count,
3473 	nvlist_t *dev_to_remove)
3474 {
3475 	nvlist_t **newdev = NULL;
3476 
3477 	if (count > 1)
3478 		newdev = kmem_alloc((count - 1) * sizeof (void *), KM_SLEEP);
3479 
3480 	for (int i = 0, j = 0; i < count; i++) {
3481 		if (dev[i] == dev_to_remove)
3482 			continue;
3483 		VERIFY(nvlist_dup(dev[i], &newdev[j++], KM_SLEEP) == 0);
3484 	}
3485 
3486 	VERIFY(nvlist_remove(config, name, DATA_TYPE_NVLIST_ARRAY) == 0);
3487 	VERIFY(nvlist_add_nvlist_array(config, name, newdev, count - 1) == 0);
3488 
3489 	for (int i = 0; i < count - 1; i++)
3490 		nvlist_free(newdev[i]);
3491 
3492 	if (count > 1)
3493 		kmem_free(newdev, (count - 1) * sizeof (void *));
3494 }
3495 
3496 /*
3497  * Removing a device from the vdev namespace requires several steps
3498  * and can take a significant amount of time.  As a result we use
3499  * the spa_vdev_config_[enter/exit] functions which allow us to
3500  * grab and release the spa_config_lock while still holding the namespace
3501  * lock.  During each step the configuration is synced out.
3502  */
3503 
3504 /*
3505  * Initial phase of device removal - stop future allocations from this device.
3506  */
3507 void
3508 spa_vdev_remove_start(spa_t *spa, vdev_t *vd)
3509 {
3510 	metaslab_group_t *mg = vd->vdev_mg;
3511 
3512 	ASSERT(MUTEX_HELD(&spa_namespace_lock));
3513 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
3514 
3515 	/*
3516 	 * Remove our vdev from the allocatable vdevs
3517 	 */
3518 	if (mg)
3519 		metaslab_class_remove(mg->mg_class, mg);
3520 }
3521 
3522 /*
3523  * Evacuate the device.
3524  */
3525 int
3526 spa_vdev_remove_evacuate(spa_t *spa, vdev_t *vd)
3527 {
3528 	uint64_t txg;
3529 	int error;
3530 
3531 	ASSERT(MUTEX_HELD(&spa_namespace_lock));
3532 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == 0);
3533 
3534 	/*
3535 	 * Evacuate the device.  We don't hold the config lock as writer
3536 	 * since we need to do I/O but we do keep the
3537 	 * spa_namespace_lock held.  Once this completes the device
3538 	 * should no longer have any blocks allocated on it.
3539 	 */
3540 	if (vd->vdev_islog) {
3541 		/*
3542 		 * Evacuate the device.
3543 		 */
3544 		if (error = dmu_objset_find(spa_name(spa),
3545 		    zil_vdev_offline, NULL, DS_FIND_CHILDREN)) {
3546 			uint64_t txg;
3547 
3548 			txg = spa_vdev_config_enter(spa);
3549 			metaslab_class_add(spa->spa_log_class,
3550 			    vd->vdev_mg);
3551 			return (spa_vdev_exit(spa, NULL, txg, error));
3552 		}
3553 		txg_wait_synced(spa_get_dsl(spa), 0);
3554 	}
3555 
3556 	/*
3557 	 * Remove any remaining MOS metadata associated with the device.
3558 	 */
3559 	txg = spa_vdev_config_enter(spa);
3560 	vd->vdev_removing = B_TRUE;
3561 	vdev_dirty(vd, 0, NULL, txg);
3562 	vdev_config_dirty(vd);
3563 	spa_vdev_config_exit(spa, NULL, txg, 0, FTAG);
3564 
3565 	return (0);
3566 }
3567 
3568 /*
3569  * Complete the removal by cleaning up the namespace.
3570  */
3571 void
3572 spa_vdev_remove_done(spa_t *spa, vdev_t *vd)
3573 {
3574 	vdev_t *rvd = spa->spa_root_vdev;
3575 	metaslab_group_t *mg = vd->vdev_mg;
3576 	uint64_t id = vd->vdev_id;
3577 	boolean_t last_vdev = (id == (rvd->vdev_children - 1));
3578 
3579 	ASSERT(MUTEX_HELD(&spa_namespace_lock));
3580 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
3581 
3582 	(void) vdev_label_init(vd, 0, VDEV_LABEL_REMOVE);
3583 	vdev_free(vd);
3584 
3585 	/*
3586 	 * It's possible that another thread is trying todo a spa_vdev_add()
3587 	 * at the same time we're trying remove it. As a result the
3588 	 * added vdev may not have initialized its metaslabs yet.
3589 	 */
3590 	if (mg != NULL)
3591 		metaslab_group_destroy(mg);
3592 
3593 	if (last_vdev) {
3594 		vdev_compact_children(rvd);
3595 	} else {
3596 		vd = vdev_alloc_common(spa, id, 0, &vdev_hole_ops);
3597 		vdev_add_child(rvd, vd);
3598 	}
3599 	vdev_config_dirty(rvd);
3600 
3601 	/*
3602 	 * Reassess the health of our root vdev.
3603 	 */
3604 	vdev_reopen(rvd);
3605 }
3606 
3607 /*
3608  * Remove a device from the pool.  Currently, this supports removing only hot
3609  * spares, slogs, and level 2 ARC devices.
3610  */
3611 int
3612 spa_vdev_remove(spa_t *spa, uint64_t guid, boolean_t unspare)
3613 {
3614 	vdev_t *vd;
3615 	nvlist_t **spares, **l2cache, *nv;
3616 	uint64_t txg = 0;
3617 	uint_t nspares, nl2cache;
3618 	int error = 0;
3619 	boolean_t locked = MUTEX_HELD(&spa_namespace_lock);
3620 
3621 	if (!locked)
3622 		txg = spa_vdev_enter(spa);
3623 
3624 	vd = spa_lookup_by_guid(spa, guid, B_FALSE);
3625 
3626 	if (spa->spa_spares.sav_vdevs != NULL &&
3627 	    nvlist_lookup_nvlist_array(spa->spa_spares.sav_config,
3628 	    ZPOOL_CONFIG_SPARES, &spares, &nspares) == 0 &&
3629 	    (nv = spa_nvlist_lookup_by_guid(spares, nspares, guid)) != NULL) {
3630 		/*
3631 		 * Only remove the hot spare if it's not currently in use
3632 		 * in this pool.
3633 		 */
3634 		if (vd == NULL || unspare) {
3635 			spa_vdev_remove_aux(spa->spa_spares.sav_config,
3636 			    ZPOOL_CONFIG_SPARES, spares, nspares, nv);
3637 			spa_load_spares(spa);
3638 			spa->spa_spares.sav_sync = B_TRUE;
3639 		} else {
3640 			error = EBUSY;
3641 		}
3642 	} else if (spa->spa_l2cache.sav_vdevs != NULL &&
3643 	    nvlist_lookup_nvlist_array(spa->spa_l2cache.sav_config,
3644 	    ZPOOL_CONFIG_L2CACHE, &l2cache, &nl2cache) == 0 &&
3645 	    (nv = spa_nvlist_lookup_by_guid(l2cache, nl2cache, guid)) != NULL) {
3646 		/*
3647 		 * Cache devices can always be removed.
3648 		 */
3649 		spa_vdev_remove_aux(spa->spa_l2cache.sav_config,
3650 		    ZPOOL_CONFIG_L2CACHE, l2cache, nl2cache, nv);
3651 		spa_load_l2cache(spa);
3652 		spa->spa_l2cache.sav_sync = B_TRUE;
3653 	} else if (vd != NULL && vd->vdev_islog) {
3654 		ASSERT(!locked);
3655 
3656 		/*
3657 		 * XXX - Once we have bp-rewrite this should
3658 		 * become the common case.
3659 		 */
3660 
3661 		/*
3662 		 * 1. Stop allocations
3663 		 * 2. Evacuate the device (i.e. kill off stubby and
3664 		 *    metadata) and wait for it to complete (i.e. sync).
3665 		 * 3. Cleanup the vdev namespace.
3666 		 */
3667 		spa_vdev_remove_start(spa, vd);
3668 
3669 		spa_vdev_config_exit(spa, NULL, txg, 0, FTAG);
3670 		if ((error = spa_vdev_remove_evacuate(spa, vd)) != 0)
3671 			return (error);
3672 		txg = spa_vdev_config_enter(spa);
3673 
3674 		spa_vdev_remove_done(spa, vd);
3675 
3676 	} else if (vd != NULL) {
3677 		/*
3678 		 * Normal vdevs cannot be removed (yet).
3679 		 */
3680 		error = ENOTSUP;
3681 	} else {
3682 		/*
3683 		 * There is no vdev of any kind with the specified guid.
3684 		 */
3685 		error = ENOENT;
3686 	}
3687 
3688 	if (!locked)
3689 		return (spa_vdev_exit(spa, NULL, txg, error));
3690 
3691 	return (error);
3692 }
3693 
3694 /*
3695  * Find any device that's done replacing, or a vdev marked 'unspare' that's
3696  * current spared, so we can detach it.
3697  */
3698 static vdev_t *
3699 spa_vdev_resilver_done_hunt(vdev_t *vd)
3700 {
3701 	vdev_t *newvd, *oldvd;
3702 
3703 	for (int c = 0; c < vd->vdev_children; c++) {
3704 		oldvd = spa_vdev_resilver_done_hunt(vd->vdev_child[c]);
3705 		if (oldvd != NULL)
3706 			return (oldvd);
3707 	}
3708 
3709 	/*
3710 	 * Check for a completed replacement.
3711 	 */
3712 	if (vd->vdev_ops == &vdev_replacing_ops && vd->vdev_children == 2) {
3713 		oldvd = vd->vdev_child[0];
3714 		newvd = vd->vdev_child[1];
3715 
3716 		if (vdev_dtl_empty(newvd, DTL_MISSING) &&
3717 		    !vdev_dtl_required(oldvd))
3718 			return (oldvd);
3719 	}
3720 
3721 	/*
3722 	 * Check for a completed resilver with the 'unspare' flag set.
3723 	 */
3724 	if (vd->vdev_ops == &vdev_spare_ops && vd->vdev_children == 2) {
3725 		newvd = vd->vdev_child[0];
3726 		oldvd = vd->vdev_child[1];
3727 
3728 		if (newvd->vdev_unspare &&
3729 		    vdev_dtl_empty(newvd, DTL_MISSING) &&
3730 		    !vdev_dtl_required(oldvd)) {
3731 			newvd->vdev_unspare = 0;
3732 			return (oldvd);
3733 		}
3734 	}
3735 
3736 	return (NULL);
3737 }
3738 
3739 static void
3740 spa_vdev_resilver_done(spa_t *spa)
3741 {
3742 	vdev_t *vd, *pvd, *ppvd;
3743 	uint64_t guid, sguid, pguid, ppguid;
3744 
3745 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3746 
3747 	while ((vd = spa_vdev_resilver_done_hunt(spa->spa_root_vdev)) != NULL) {
3748 		pvd = vd->vdev_parent;
3749 		ppvd = pvd->vdev_parent;
3750 		guid = vd->vdev_guid;
3751 		pguid = pvd->vdev_guid;
3752 		ppguid = ppvd->vdev_guid;
3753 		sguid = 0;
3754 		/*
3755 		 * If we have just finished replacing a hot spared device, then
3756 		 * we need to detach the parent's first child (the original hot
3757 		 * spare) as well.
3758 		 */
3759 		if (ppvd->vdev_ops == &vdev_spare_ops && pvd->vdev_id == 0) {
3760 			ASSERT(pvd->vdev_ops == &vdev_replacing_ops);
3761 			ASSERT(ppvd->vdev_children == 2);
3762 			sguid = ppvd->vdev_child[1]->vdev_guid;
3763 		}
3764 		spa_config_exit(spa, SCL_ALL, FTAG);
3765 		if (spa_vdev_detach(spa, guid, pguid, B_TRUE) != 0)
3766 			return;
3767 		if (sguid && spa_vdev_detach(spa, sguid, ppguid, B_TRUE) != 0)
3768 			return;
3769 		spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
3770 	}
3771 
3772 	spa_config_exit(spa, SCL_ALL, FTAG);
3773 }
3774 
3775 /*
3776  * Update the stored path or FRU for this vdev.  Dirty the vdev configuration,
3777  * relying on spa_vdev_enter/exit() to synchronize the labels and cache.
3778  */
3779 int
3780 spa_vdev_set_common(spa_t *spa, uint64_t guid, const char *value,
3781     boolean_t ispath)
3782 {
3783 	vdev_t *vd;
3784 	uint64_t txg;
3785 
3786 	txg = spa_vdev_enter(spa);
3787 
3788 	if ((vd = spa_lookup_by_guid(spa, guid, B_TRUE)) == NULL)
3789 		return (spa_vdev_exit(spa, NULL, txg, ENOENT));
3790 
3791 	if (!vd->vdev_ops->vdev_op_leaf)
3792 		return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
3793 
3794 	if (ispath) {
3795 		spa_strfree(vd->vdev_path);
3796 		vd->vdev_path = spa_strdup(value);
3797 	} else {
3798 		if (vd->vdev_fru != NULL)
3799 			spa_strfree(vd->vdev_fru);
3800 		vd->vdev_fru = spa_strdup(value);
3801 	}
3802 
3803 	vdev_config_dirty(vd->vdev_top);
3804 
3805 	return (spa_vdev_exit(spa, NULL, txg, 0));
3806 }
3807 
3808 int
3809 spa_vdev_setpath(spa_t *spa, uint64_t guid, const char *newpath)
3810 {
3811 	return (spa_vdev_set_common(spa, guid, newpath, B_TRUE));
3812 }
3813 
3814 int
3815 spa_vdev_setfru(spa_t *spa, uint64_t guid, const char *newfru)
3816 {
3817 	return (spa_vdev_set_common(spa, guid, newfru, B_FALSE));
3818 }
3819 
3820 /*
3821  * ==========================================================================
3822  * SPA Scrubbing
3823  * ==========================================================================
3824  */
3825 
3826 int
3827 spa_scrub(spa_t *spa, pool_scrub_type_t type)
3828 {
3829 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == 0);
3830 
3831 	if ((uint_t)type >= POOL_SCRUB_TYPES)
3832 		return (ENOTSUP);
3833 
3834 	/*
3835 	 * If a resilver was requested, but there is no DTL on a
3836 	 * writeable leaf device, we have nothing to do.
3837 	 */
3838 	if (type == POOL_SCRUB_RESILVER &&
3839 	    !vdev_resilver_needed(spa->spa_root_vdev, NULL, NULL)) {
3840 		spa_async_request(spa, SPA_ASYNC_RESILVER_DONE);
3841 		return (0);
3842 	}
3843 
3844 	if (type == POOL_SCRUB_EVERYTHING &&
3845 	    spa->spa_dsl_pool->dp_scrub_func != SCRUB_FUNC_NONE &&
3846 	    spa->spa_dsl_pool->dp_scrub_isresilver)
3847 		return (EBUSY);
3848 
3849 	if (type == POOL_SCRUB_EVERYTHING || type == POOL_SCRUB_RESILVER) {
3850 		return (dsl_pool_scrub_clean(spa->spa_dsl_pool));
3851 	} else if (type == POOL_SCRUB_NONE) {
3852 		return (dsl_pool_scrub_cancel(spa->spa_dsl_pool));
3853 	} else {
3854 		return (EINVAL);
3855 	}
3856 }
3857 
3858 /*
3859  * ==========================================================================
3860  * SPA async task processing
3861  * ==========================================================================
3862  */
3863 
3864 static void
3865 spa_async_remove(spa_t *spa, vdev_t *vd)
3866 {
3867 	if (vd->vdev_remove_wanted) {
3868 		vd->vdev_remove_wanted = 0;
3869 		vdev_set_state(vd, B_FALSE, VDEV_STATE_REMOVED, VDEV_AUX_NONE);
3870 
3871 		/*
3872 		 * We want to clear the stats, but we don't want to do a full
3873 		 * vdev_clear() as that will cause us to throw away
3874 		 * degraded/faulted state as well as attempt to reopen the
3875 		 * device, all of which is a waste.
3876 		 */
3877 		vd->vdev_stat.vs_read_errors = 0;
3878 		vd->vdev_stat.vs_write_errors = 0;
3879 		vd->vdev_stat.vs_checksum_errors = 0;
3880 
3881 		vdev_state_dirty(vd->vdev_top);
3882 	}
3883 
3884 	for (int c = 0; c < vd->vdev_children; c++)
3885 		spa_async_remove(spa, vd->vdev_child[c]);
3886 }
3887 
3888 static void
3889 spa_async_probe(spa_t *spa, vdev_t *vd)
3890 {
3891 	if (vd->vdev_probe_wanted) {
3892 		vd->vdev_probe_wanted = 0;
3893 		vdev_reopen(vd);	/* vdev_open() does the actual probe */
3894 	}
3895 
3896 	for (int c = 0; c < vd->vdev_children; c++)
3897 		spa_async_probe(spa, vd->vdev_child[c]);
3898 }
3899 
3900 static void
3901 spa_async_autoexpand(spa_t *spa, vdev_t *vd)
3902 {
3903 	sysevent_id_t eid;
3904 	nvlist_t *attr;
3905 	char *physpath;
3906 
3907 	if (!spa->spa_autoexpand)
3908 		return;
3909 
3910 	for (int c = 0; c < vd->vdev_children; c++) {
3911 		vdev_t *cvd = vd->vdev_child[c];
3912 		spa_async_autoexpand(spa, cvd);
3913 	}
3914 
3915 	if (!vd->vdev_ops->vdev_op_leaf || vd->vdev_physpath == NULL)
3916 		return;
3917 
3918 	physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
3919 	(void) snprintf(physpath, MAXPATHLEN, "/devices%s", vd->vdev_physpath);
3920 
3921 	VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
3922 	VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
3923 
3924 	(void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
3925 	    ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
3926 
3927 	nvlist_free(attr);
3928 	kmem_free(physpath, MAXPATHLEN);
3929 }
3930 
3931 static void
3932 spa_async_thread(spa_t *spa)
3933 {
3934 	int tasks;
3935 
3936 	ASSERT(spa->spa_sync_on);
3937 
3938 	mutex_enter(&spa->spa_async_lock);
3939 	tasks = spa->spa_async_tasks;
3940 	spa->spa_async_tasks = 0;
3941 	mutex_exit(&spa->spa_async_lock);
3942 
3943 	/*
3944 	 * See if the config needs to be updated.
3945 	 */
3946 	if (tasks & SPA_ASYNC_CONFIG_UPDATE) {
3947 		uint64_t oldsz, space_update;
3948 
3949 		mutex_enter(&spa_namespace_lock);
3950 		oldsz = spa_get_space(spa);
3951 		spa_config_update(spa, SPA_CONFIG_UPDATE_POOL);
3952 		space_update = spa_get_space(spa) - oldsz;
3953 		mutex_exit(&spa_namespace_lock);
3954 
3955 		/*
3956 		 * If the pool grew as a result of the config update,
3957 		 * then log an internal history event.
3958 		 */
3959 		if (space_update) {
3960 			spa_history_internal_log(LOG_POOL_VDEV_ONLINE,
3961 			    spa, NULL, CRED(),
3962 			    "pool '%s' size: %llu(+%llu)",
3963 			    spa_name(spa), spa_get_space(spa),
3964 			    space_update);
3965 		}
3966 	}
3967 
3968 	/*
3969 	 * See if any devices need to be marked REMOVED.
3970 	 */
3971 	if (tasks & SPA_ASYNC_REMOVE) {
3972 		spa_vdev_state_enter(spa, SCL_NONE);
3973 		spa_async_remove(spa, spa->spa_root_vdev);
3974 		for (int i = 0; i < spa->spa_l2cache.sav_count; i++)
3975 			spa_async_remove(spa, spa->spa_l2cache.sav_vdevs[i]);
3976 		for (int i = 0; i < spa->spa_spares.sav_count; i++)
3977 			spa_async_remove(spa, spa->spa_spares.sav_vdevs[i]);
3978 		(void) spa_vdev_state_exit(spa, NULL, 0);
3979 	}
3980 
3981 	if ((tasks & SPA_ASYNC_AUTOEXPAND) && !spa_suspended(spa)) {
3982 		spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
3983 		spa_async_autoexpand(spa, spa->spa_root_vdev);
3984 		spa_config_exit(spa, SCL_CONFIG, FTAG);
3985 	}
3986 
3987 	/*
3988 	 * See if any devices need to be probed.
3989 	 */
3990 	if (tasks & SPA_ASYNC_PROBE) {
3991 		spa_vdev_state_enter(spa, SCL_NONE);
3992 		spa_async_probe(spa, spa->spa_root_vdev);
3993 		(void) spa_vdev_state_exit(spa, NULL, 0);
3994 	}
3995 
3996 	/*
3997 	 * If any devices are done replacing, detach them.
3998 	 */
3999 	if (tasks & SPA_ASYNC_RESILVER_DONE)
4000 		spa_vdev_resilver_done(spa);
4001 
4002 	/*
4003 	 * Kick off a resilver.
4004 	 */
4005 	if (tasks & SPA_ASYNC_RESILVER)
4006 		VERIFY(spa_scrub(spa, POOL_SCRUB_RESILVER) == 0);
4007 
4008 	/*
4009 	 * Let the world know that we're done.
4010 	 */
4011 	mutex_enter(&spa->spa_async_lock);
4012 	spa->spa_async_thread = NULL;
4013 	cv_broadcast(&spa->spa_async_cv);
4014 	mutex_exit(&spa->spa_async_lock);
4015 	thread_exit();
4016 }
4017 
4018 void
4019 spa_async_suspend(spa_t *spa)
4020 {
4021 	mutex_enter(&spa->spa_async_lock);
4022 	spa->spa_async_suspended++;
4023 	while (spa->spa_async_thread != NULL)
4024 		cv_wait(&spa->spa_async_cv, &spa->spa_async_lock);
4025 	mutex_exit(&spa->spa_async_lock);
4026 }
4027 
4028 void
4029 spa_async_resume(spa_t *spa)
4030 {
4031 	mutex_enter(&spa->spa_async_lock);
4032 	ASSERT(spa->spa_async_suspended != 0);
4033 	spa->spa_async_suspended--;
4034 	mutex_exit(&spa->spa_async_lock);
4035 }
4036 
4037 static void
4038 spa_async_dispatch(spa_t *spa)
4039 {
4040 	mutex_enter(&spa->spa_async_lock);
4041 	if (spa->spa_async_tasks && !spa->spa_async_suspended &&
4042 	    spa->spa_async_thread == NULL &&
4043 	    rootdir != NULL && !vn_is_readonly(rootdir))
4044 		spa->spa_async_thread = thread_create(NULL, 0,
4045 		    spa_async_thread, spa, 0, &p0, TS_RUN, maxclsyspri);
4046 	mutex_exit(&spa->spa_async_lock);
4047 }
4048 
4049 void
4050 spa_async_request(spa_t *spa, int task)
4051 {
4052 	mutex_enter(&spa->spa_async_lock);
4053 	spa->spa_async_tasks |= task;
4054 	mutex_exit(&spa->spa_async_lock);
4055 }
4056 
4057 /*
4058  * ==========================================================================
4059  * SPA syncing routines
4060  * ==========================================================================
4061  */
4062 
4063 static void
4064 spa_sync_deferred_frees(spa_t *spa, uint64_t txg)
4065 {
4066 	bplist_t *bpl = &spa->spa_sync_bplist;
4067 	dmu_tx_t *tx;
4068 	blkptr_t blk;
4069 	uint64_t itor = 0;
4070 	zio_t *zio;
4071 	int error;
4072 	uint8_t c = 1;
4073 
4074 	zio = zio_root(spa, NULL, NULL, ZIO_FLAG_CANFAIL);
4075 
4076 	while (bplist_iterate(bpl, &itor, &blk) == 0) {
4077 		ASSERT(blk.blk_birth < txg);
4078 		zio_nowait(zio_free(zio, spa, txg, &blk, NULL, NULL,
4079 		    ZIO_FLAG_MUSTSUCCEED));
4080 	}
4081 
4082 	error = zio_wait(zio);
4083 	ASSERT3U(error, ==, 0);
4084 
4085 	tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg);
4086 	bplist_vacate(bpl, tx);
4087 
4088 	/*
4089 	 * Pre-dirty the first block so we sync to convergence faster.
4090 	 * (Usually only the first block is needed.)
4091 	 */
4092 	dmu_write(spa->spa_meta_objset, spa->spa_sync_bplist_obj, 0, 1, &c, tx);
4093 	dmu_tx_commit(tx);
4094 }
4095 
4096 static void
4097 spa_sync_nvlist(spa_t *spa, uint64_t obj, nvlist_t *nv, dmu_tx_t *tx)
4098 {
4099 	char *packed = NULL;
4100 	size_t bufsize;
4101 	size_t nvsize = 0;
4102 	dmu_buf_t *db;
4103 
4104 	VERIFY(nvlist_size(nv, &nvsize, NV_ENCODE_XDR) == 0);
4105 
4106 	/*
4107 	 * Write full (SPA_CONFIG_BLOCKSIZE) blocks of configuration
4108 	 * information.  This avoids the dbuf_will_dirty() path and
4109 	 * saves us a pre-read to get data we don't actually care about.
4110 	 */
4111 	bufsize = P2ROUNDUP(nvsize, SPA_CONFIG_BLOCKSIZE);
4112 	packed = kmem_alloc(bufsize, KM_SLEEP);
4113 
4114 	VERIFY(nvlist_pack(nv, &packed, &nvsize, NV_ENCODE_XDR,
4115 	    KM_SLEEP) == 0);
4116 	bzero(packed + nvsize, bufsize - nvsize);
4117 
4118 	dmu_write(spa->spa_meta_objset, obj, 0, bufsize, packed, tx);
4119 
4120 	kmem_free(packed, bufsize);
4121 
4122 	VERIFY(0 == dmu_bonus_hold(spa->spa_meta_objset, obj, FTAG, &db));
4123 	dmu_buf_will_dirty(db, tx);
4124 	*(uint64_t *)db->db_data = nvsize;
4125 	dmu_buf_rele(db, FTAG);
4126 }
4127 
4128 static void
4129 spa_sync_aux_dev(spa_t *spa, spa_aux_vdev_t *sav, dmu_tx_t *tx,
4130     const char *config, const char *entry)
4131 {
4132 	nvlist_t *nvroot;
4133 	nvlist_t **list;
4134 	int i;
4135 
4136 	if (!sav->sav_sync)
4137 		return;
4138 
4139 	/*
4140 	 * Update the MOS nvlist describing the list of available devices.
4141 	 * spa_validate_aux() will have already made sure this nvlist is
4142 	 * valid and the vdevs are labeled appropriately.
4143 	 */
4144 	if (sav->sav_object == 0) {
4145 		sav->sav_object = dmu_object_alloc(spa->spa_meta_objset,
4146 		    DMU_OT_PACKED_NVLIST, 1 << 14, DMU_OT_PACKED_NVLIST_SIZE,
4147 		    sizeof (uint64_t), tx);
4148 		VERIFY(zap_update(spa->spa_meta_objset,
4149 		    DMU_POOL_DIRECTORY_OBJECT, entry, sizeof (uint64_t), 1,
4150 		    &sav->sav_object, tx) == 0);
4151 	}
4152 
4153 	VERIFY(nvlist_alloc(&nvroot, NV_UNIQUE_NAME, KM_SLEEP) == 0);
4154 	if (sav->sav_count == 0) {
4155 		VERIFY(nvlist_add_nvlist_array(nvroot, config, NULL, 0) == 0);
4156 	} else {
4157 		list = kmem_alloc(sav->sav_count * sizeof (void *), KM_SLEEP);
4158 		for (i = 0; i < sav->sav_count; i++)
4159 			list[i] = vdev_config_generate(spa, sav->sav_vdevs[i],
4160 			    B_FALSE, B_FALSE, B_TRUE);
4161 		VERIFY(nvlist_add_nvlist_array(nvroot, config, list,
4162 		    sav->sav_count) == 0);
4163 		for (i = 0; i < sav->sav_count; i++)
4164 			nvlist_free(list[i]);
4165 		kmem_free(list, sav->sav_count * sizeof (void *));
4166 	}
4167 
4168 	spa_sync_nvlist(spa, sav->sav_object, nvroot, tx);
4169 	nvlist_free(nvroot);
4170 
4171 	sav->sav_sync = B_FALSE;
4172 }
4173 
4174 static void
4175 spa_sync_config_object(spa_t *spa, dmu_tx_t *tx)
4176 {
4177 	nvlist_t *config;
4178 
4179 	if (list_is_empty(&spa->spa_config_dirty_list))
4180 		return;
4181 
4182 	spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
4183 
4184 	config = spa_config_generate(spa, spa->spa_root_vdev,
4185 	    dmu_tx_get_txg(tx), B_FALSE);
4186 
4187 	spa_config_exit(spa, SCL_STATE, FTAG);
4188 
4189 	if (spa->spa_config_syncing)
4190 		nvlist_free(spa->spa_config_syncing);
4191 	spa->spa_config_syncing = config;
4192 
4193 	spa_sync_nvlist(spa, spa->spa_config_object, config, tx);
4194 }
4195 
4196 /*
4197  * Set zpool properties.
4198  */
4199 static void
4200 spa_sync_props(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
4201 {
4202 	spa_t *spa = arg1;
4203 	objset_t *mos = spa->spa_meta_objset;
4204 	nvlist_t *nvp = arg2;
4205 	nvpair_t *elem;
4206 	uint64_t intval;
4207 	char *strval;
4208 	zpool_prop_t prop;
4209 	const char *propname;
4210 	zprop_type_t proptype;
4211 
4212 	mutex_enter(&spa->spa_props_lock);
4213 
4214 	elem = NULL;
4215 	while ((elem = nvlist_next_nvpair(nvp, elem))) {
4216 		switch (prop = zpool_name_to_prop(nvpair_name(elem))) {
4217 		case ZPOOL_PROP_VERSION:
4218 			/*
4219 			 * Only set version for non-zpool-creation cases
4220 			 * (set/import). spa_create() needs special care
4221 			 * for version setting.
4222 			 */
4223 			if (tx->tx_txg != TXG_INITIAL) {
4224 				VERIFY(nvpair_value_uint64(elem,
4225 				    &intval) == 0);
4226 				ASSERT(intval <= SPA_VERSION);
4227 				ASSERT(intval >= spa_version(spa));
4228 				spa->spa_uberblock.ub_version = intval;
4229 				vdev_config_dirty(spa->spa_root_vdev);
4230 			}
4231 			break;
4232 
4233 		case ZPOOL_PROP_ALTROOT:
4234 			/*
4235 			 * 'altroot' is a non-persistent property. It should
4236 			 * have been set temporarily at creation or import time.
4237 			 */
4238 			ASSERT(spa->spa_root != NULL);
4239 			break;
4240 
4241 		case ZPOOL_PROP_CACHEFILE:
4242 			/*
4243 			 * 'cachefile' is also a non-persisitent property.
4244 			 */
4245 			break;
4246 		default:
4247 			/*
4248 			 * Set pool property values in the poolprops mos object.
4249 			 */
4250 			if (spa->spa_pool_props_object == 0) {
4251 				objset_t *mos = spa->spa_meta_objset;
4252 
4253 				VERIFY((spa->spa_pool_props_object =
4254 				    zap_create(mos, DMU_OT_POOL_PROPS,
4255 				    DMU_OT_NONE, 0, tx)) > 0);
4256 
4257 				VERIFY(zap_update(mos,
4258 				    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_PROPS,
4259 				    8, 1, &spa->spa_pool_props_object, tx)
4260 				    == 0);
4261 			}
4262 
4263 			/* normalize the property name */
4264 			propname = zpool_prop_to_name(prop);
4265 			proptype = zpool_prop_get_type(prop);
4266 
4267 			if (nvpair_type(elem) == DATA_TYPE_STRING) {
4268 				ASSERT(proptype == PROP_TYPE_STRING);
4269 				VERIFY(nvpair_value_string(elem, &strval) == 0);
4270 				VERIFY(zap_update(mos,
4271 				    spa->spa_pool_props_object, propname,
4272 				    1, strlen(strval) + 1, strval, tx) == 0);
4273 
4274 			} else if (nvpair_type(elem) == DATA_TYPE_UINT64) {
4275 				VERIFY(nvpair_value_uint64(elem, &intval) == 0);
4276 
4277 				if (proptype == PROP_TYPE_INDEX) {
4278 					const char *unused;
4279 					VERIFY(zpool_prop_index_to_string(
4280 					    prop, intval, &unused) == 0);
4281 				}
4282 				VERIFY(zap_update(mos,
4283 				    spa->spa_pool_props_object, propname,
4284 				    8, 1, &intval, tx) == 0);
4285 			} else {
4286 				ASSERT(0); /* not allowed */
4287 			}
4288 
4289 			switch (prop) {
4290 			case ZPOOL_PROP_DELEGATION:
4291 				spa->spa_delegation = intval;
4292 				break;
4293 			case ZPOOL_PROP_BOOTFS:
4294 				spa->spa_bootfs = intval;
4295 				break;
4296 			case ZPOOL_PROP_FAILUREMODE:
4297 				spa->spa_failmode = intval;
4298 				break;
4299 			case ZPOOL_PROP_AUTOEXPAND:
4300 				spa->spa_autoexpand = intval;
4301 				spa_async_request(spa, SPA_ASYNC_AUTOEXPAND);
4302 				break;
4303 			default:
4304 				break;
4305 			}
4306 		}
4307 
4308 		/* log internal history if this is not a zpool create */
4309 		if (spa_version(spa) >= SPA_VERSION_ZPOOL_HISTORY &&
4310 		    tx->tx_txg != TXG_INITIAL) {
4311 			spa_history_internal_log(LOG_POOL_PROPSET,
4312 			    spa, tx, cr, "%s %lld %s",
4313 			    nvpair_name(elem), intval, spa_name(spa));
4314 		}
4315 	}
4316 
4317 	mutex_exit(&spa->spa_props_lock);
4318 }
4319 
4320 /*
4321  * Sync the specified transaction group.  New blocks may be dirtied as
4322  * part of the process, so we iterate until it converges.
4323  */
4324 void
4325 spa_sync(spa_t *spa, uint64_t txg)
4326 {
4327 	dsl_pool_t *dp = spa->spa_dsl_pool;
4328 	objset_t *mos = spa->spa_meta_objset;
4329 	bplist_t *bpl = &spa->spa_sync_bplist;
4330 	vdev_t *rvd = spa->spa_root_vdev;
4331 	vdev_t *vd;
4332 	dmu_tx_t *tx;
4333 	int dirty_vdevs;
4334 	int error;
4335 
4336 	/*
4337 	 * Lock out configuration changes.
4338 	 */
4339 	spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
4340 
4341 	spa->spa_syncing_txg = txg;
4342 	spa->spa_sync_pass = 0;
4343 
4344 	/*
4345 	 * If there are any pending vdev state changes, convert them
4346 	 * into config changes that go out with this transaction group.
4347 	 */
4348 	spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
4349 	while (list_head(&spa->spa_state_dirty_list) != NULL) {
4350 		/*
4351 		 * We need the write lock here because, for aux vdevs,
4352 		 * calling vdev_config_dirty() modifies sav_config.
4353 		 * This is ugly and will become unnecessary when we
4354 		 * eliminate the aux vdev wart by integrating all vdevs
4355 		 * into the root vdev tree.
4356 		 */
4357 		spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
4358 		spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_WRITER);
4359 		while ((vd = list_head(&spa->spa_state_dirty_list)) != NULL) {
4360 			vdev_state_clean(vd);
4361 			vdev_config_dirty(vd);
4362 		}
4363 		spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
4364 		spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER);
4365 	}
4366 	spa_config_exit(spa, SCL_STATE, FTAG);
4367 
4368 	VERIFY(0 == bplist_open(bpl, mos, spa->spa_sync_bplist_obj));
4369 
4370 	tx = dmu_tx_create_assigned(dp, txg);
4371 
4372 	/*
4373 	 * If we are upgrading to SPA_VERSION_RAIDZ_DEFLATE this txg,
4374 	 * set spa_deflate if we have no raid-z vdevs.
4375 	 */
4376 	if (spa->spa_ubsync.ub_version < SPA_VERSION_RAIDZ_DEFLATE &&
4377 	    spa->spa_uberblock.ub_version >= SPA_VERSION_RAIDZ_DEFLATE) {
4378 		int i;
4379 
4380 		for (i = 0; i < rvd->vdev_children; i++) {
4381 			vd = rvd->vdev_child[i];
4382 			if (vd->vdev_deflate_ratio != SPA_MINBLOCKSIZE)
4383 				break;
4384 		}
4385 		if (i == rvd->vdev_children) {
4386 			spa->spa_deflate = TRUE;
4387 			VERIFY(0 == zap_add(spa->spa_meta_objset,
4388 			    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_DEFLATE,
4389 			    sizeof (uint64_t), 1, &spa->spa_deflate, tx));
4390 		}
4391 	}
4392 
4393 	if (spa->spa_ubsync.ub_version < SPA_VERSION_ORIGIN &&
4394 	    spa->spa_uberblock.ub_version >= SPA_VERSION_ORIGIN) {
4395 		dsl_pool_create_origin(dp, tx);
4396 
4397 		/* Keeping the origin open increases spa_minref */
4398 		spa->spa_minref += 3;
4399 	}
4400 
4401 	if (spa->spa_ubsync.ub_version < SPA_VERSION_NEXT_CLONES &&
4402 	    spa->spa_uberblock.ub_version >= SPA_VERSION_NEXT_CLONES) {
4403 		dsl_pool_upgrade_clones(dp, tx);
4404 	}
4405 
4406 	/*
4407 	 * If anything has changed in this txg, push the deferred frees
4408 	 * from the previous txg.  If not, leave them alone so that we
4409 	 * don't generate work on an otherwise idle system.
4410 	 */
4411 	if (!txg_list_empty(&dp->dp_dirty_datasets, txg) ||
4412 	    !txg_list_empty(&dp->dp_dirty_dirs, txg) ||
4413 	    !txg_list_empty(&dp->dp_sync_tasks, txg))
4414 		spa_sync_deferred_frees(spa, txg);
4415 
4416 	/*
4417 	 * Iterate to convergence.
4418 	 */
4419 	do {
4420 		spa->spa_sync_pass++;
4421 
4422 		spa_sync_config_object(spa, tx);
4423 		spa_sync_aux_dev(spa, &spa->spa_spares, tx,
4424 		    ZPOOL_CONFIG_SPARES, DMU_POOL_SPARES);
4425 		spa_sync_aux_dev(spa, &spa->spa_l2cache, tx,
4426 		    ZPOOL_CONFIG_L2CACHE, DMU_POOL_L2CACHE);
4427 		spa_errlog_sync(spa, txg);
4428 		dsl_pool_sync(dp, txg);
4429 
4430 		dirty_vdevs = 0;
4431 		while (vd = txg_list_remove(&spa->spa_vdev_txg_list, txg)) {
4432 			vdev_sync(vd, txg);
4433 			dirty_vdevs++;
4434 		}
4435 
4436 		bplist_sync(bpl, tx);
4437 	} while (dirty_vdevs);
4438 
4439 	bplist_close(bpl);
4440 
4441 	dprintf("txg %llu passes %d\n", txg, spa->spa_sync_pass);
4442 
4443 	/*
4444 	 * Rewrite the vdev configuration (which includes the uberblock)
4445 	 * to commit the transaction group.
4446 	 *
4447 	 * If there are no dirty vdevs, we sync the uberblock to a few
4448 	 * random top-level vdevs that are known to be visible in the
4449 	 * config cache (see spa_vdev_add() for a complete description).
4450 	 * If there *are* dirty vdevs, sync the uberblock to all vdevs.
4451 	 */
4452 	for (;;) {
4453 		/*
4454 		 * We hold SCL_STATE to prevent vdev open/close/etc.
4455 		 * while we're attempting to write the vdev labels.
4456 		 */
4457 		spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
4458 
4459 		if (list_is_empty(&spa->spa_config_dirty_list)) {
4460 			vdev_t *svd[SPA_DVAS_PER_BP];
4461 			int svdcount = 0;
4462 			int children = rvd->vdev_children;
4463 			int c0 = spa_get_random(children);
4464 
4465 			for (int c = 0; c < children; c++) {
4466 				vd = rvd->vdev_child[(c0 + c) % children];
4467 				if (vd->vdev_ms_array == 0 || vd->vdev_islog)
4468 					continue;
4469 				svd[svdcount++] = vd;
4470 				if (svdcount == SPA_DVAS_PER_BP)
4471 					break;
4472 			}
4473 			error = vdev_config_sync(svd, svdcount, txg, B_FALSE);
4474 			if (error != 0)
4475 				error = vdev_config_sync(svd, svdcount, txg,
4476 				    B_TRUE);
4477 		} else {
4478 			error = vdev_config_sync(rvd->vdev_child,
4479 			    rvd->vdev_children, txg, B_FALSE);
4480 			if (error != 0)
4481 				error = vdev_config_sync(rvd->vdev_child,
4482 				    rvd->vdev_children, txg, B_TRUE);
4483 		}
4484 
4485 		spa_config_exit(spa, SCL_STATE, FTAG);
4486 
4487 		if (error == 0)
4488 			break;
4489 		zio_suspend(spa, NULL);
4490 		zio_resume_wait(spa);
4491 	}
4492 	dmu_tx_commit(tx);
4493 
4494 	/*
4495 	 * Clear the dirty config list.
4496 	 */
4497 	while ((vd = list_head(&spa->spa_config_dirty_list)) != NULL)
4498 		vdev_config_clean(vd);
4499 
4500 	/*
4501 	 * Now that the new config has synced transactionally,
4502 	 * let it become visible to the config cache.
4503 	 */
4504 	if (spa->spa_config_syncing != NULL) {
4505 		spa_config_set(spa, spa->spa_config_syncing);
4506 		spa->spa_config_txg = txg;
4507 		spa->spa_config_syncing = NULL;
4508 	}
4509 
4510 	spa->spa_ubsync = spa->spa_uberblock;
4511 
4512 	/*
4513 	 * Clean up the ZIL records for the synced txg.
4514 	 */
4515 	dsl_pool_zil_clean(dp);
4516 
4517 	/*
4518 	 * Update usable space statistics.
4519 	 */
4520 	while (vd = txg_list_remove(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)))
4521 		vdev_sync_done(vd, txg);
4522 
4523 	/*
4524 	 * It had better be the case that we didn't dirty anything
4525 	 * since vdev_config_sync().
4526 	 */
4527 	ASSERT(txg_list_empty(&dp->dp_dirty_datasets, txg));
4528 	ASSERT(txg_list_empty(&dp->dp_dirty_dirs, txg));
4529 	ASSERT(txg_list_empty(&spa->spa_vdev_txg_list, txg));
4530 	ASSERT(bpl->bpl_queue == NULL);
4531 
4532 	spa_config_exit(spa, SCL_CONFIG, FTAG);
4533 
4534 	/*
4535 	 * If any async tasks have been requested, kick them off.
4536 	 */
4537 	spa_async_dispatch(spa);
4538 }
4539 
4540 /*
4541  * Sync all pools.  We don't want to hold the namespace lock across these
4542  * operations, so we take a reference on the spa_t and drop the lock during the
4543  * sync.
4544  */
4545 void
4546 spa_sync_allpools(void)
4547 {
4548 	spa_t *spa = NULL;
4549 	mutex_enter(&spa_namespace_lock);
4550 	while ((spa = spa_next(spa)) != NULL) {
4551 		if (spa_state(spa) != POOL_STATE_ACTIVE || spa_suspended(spa))
4552 			continue;
4553 		spa_open_ref(spa, FTAG);
4554 		mutex_exit(&spa_namespace_lock);
4555 		txg_wait_synced(spa_get_dsl(spa), 0);
4556 		mutex_enter(&spa_namespace_lock);
4557 		spa_close(spa, FTAG);
4558 	}
4559 	mutex_exit(&spa_namespace_lock);
4560 }
4561 
4562 /*
4563  * ==========================================================================
4564  * Miscellaneous routines
4565  * ==========================================================================
4566  */
4567 
4568 /*
4569  * Remove all pools in the system.
4570  */
4571 void
4572 spa_evict_all(void)
4573 {
4574 	spa_t *spa;
4575 
4576 	/*
4577 	 * Remove all cached state.  All pools should be closed now,
4578 	 * so every spa in the AVL tree should be unreferenced.
4579 	 */
4580 	mutex_enter(&spa_namespace_lock);
4581 	while ((spa = spa_next(NULL)) != NULL) {
4582 		/*
4583 		 * Stop async tasks.  The async thread may need to detach
4584 		 * a device that's been replaced, which requires grabbing
4585 		 * spa_namespace_lock, so we must drop it here.
4586 		 */
4587 		spa_open_ref(spa, FTAG);
4588 		mutex_exit(&spa_namespace_lock);
4589 		spa_async_suspend(spa);
4590 		mutex_enter(&spa_namespace_lock);
4591 		spa_close(spa, FTAG);
4592 
4593 		if (spa->spa_state != POOL_STATE_UNINITIALIZED) {
4594 			spa_unload(spa);
4595 			spa_deactivate(spa);
4596 		}
4597 		spa_remove(spa);
4598 	}
4599 	mutex_exit(&spa_namespace_lock);
4600 }
4601 
4602 vdev_t *
4603 spa_lookup_by_guid(spa_t *spa, uint64_t guid, boolean_t aux)
4604 {
4605 	vdev_t *vd;
4606 	int i;
4607 
4608 	if ((vd = vdev_lookup_by_guid(spa->spa_root_vdev, guid)) != NULL)
4609 		return (vd);
4610 
4611 	if (aux) {
4612 		for (i = 0; i < spa->spa_l2cache.sav_count; i++) {
4613 			vd = spa->spa_l2cache.sav_vdevs[i];
4614 			if (vd->vdev_guid == guid)
4615 				return (vd);
4616 		}
4617 
4618 		for (i = 0; i < spa->spa_spares.sav_count; i++) {
4619 			vd = spa->spa_spares.sav_vdevs[i];
4620 			if (vd->vdev_guid == guid)
4621 				return (vd);
4622 		}
4623 	}
4624 
4625 	return (NULL);
4626 }
4627 
4628 void
4629 spa_upgrade(spa_t *spa, uint64_t version)
4630 {
4631 	spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
4632 
4633 	/*
4634 	 * This should only be called for a non-faulted pool, and since a
4635 	 * future version would result in an unopenable pool, this shouldn't be
4636 	 * possible.
4637 	 */
4638 	ASSERT(spa->spa_uberblock.ub_version <= SPA_VERSION);
4639 	ASSERT(version >= spa->spa_uberblock.ub_version);
4640 
4641 	spa->spa_uberblock.ub_version = version;
4642 	vdev_config_dirty(spa->spa_root_vdev);
4643 
4644 	spa_config_exit(spa, SCL_ALL, FTAG);
4645 
4646 	txg_wait_synced(spa_get_dsl(spa), 0);
4647 }
4648 
4649 boolean_t
4650 spa_has_spare(spa_t *spa, uint64_t guid)
4651 {
4652 	int i;
4653 	uint64_t spareguid;
4654 	spa_aux_vdev_t *sav = &spa->spa_spares;
4655 
4656 	for (i = 0; i < sav->sav_count; i++)
4657 		if (sav->sav_vdevs[i]->vdev_guid == guid)
4658 			return (B_TRUE);
4659 
4660 	for (i = 0; i < sav->sav_npending; i++) {
4661 		if (nvlist_lookup_uint64(sav->sav_pending[i], ZPOOL_CONFIG_GUID,
4662 		    &spareguid) == 0 && spareguid == guid)
4663 			return (B_TRUE);
4664 	}
4665 
4666 	return (B_FALSE);
4667 }
4668 
4669 /*
4670  * Check if a pool has an active shared spare device.
4671  * Note: reference count of an active spare is 2, as a spare and as a replace
4672  */
4673 static boolean_t
4674 spa_has_active_shared_spare(spa_t *spa)
4675 {
4676 	int i, refcnt;
4677 	uint64_t pool;
4678 	spa_aux_vdev_t *sav = &spa->spa_spares;
4679 
4680 	for (i = 0; i < sav->sav_count; i++) {
4681 		if (spa_spare_exists(sav->sav_vdevs[i]->vdev_guid, &pool,
4682 		    &refcnt) && pool != 0ULL && pool == spa_guid(spa) &&
4683 		    refcnt > 2)
4684 			return (B_TRUE);
4685 	}
4686 
4687 	return (B_FALSE);
4688 }
4689 
4690 /*
4691  * Post a sysevent corresponding to the given event.  The 'name' must be one of
4692  * the event definitions in sys/sysevent/eventdefs.h.  The payload will be
4693  * filled in from the spa and (optionally) the vdev.  This doesn't do anything
4694  * in the userland libzpool, as we don't want consumers to misinterpret ztest
4695  * or zdb as real changes.
4696  */
4697 void
4698 spa_event_notify(spa_t *spa, vdev_t *vd, const char *name)
4699 {
4700 #ifdef _KERNEL
4701 	sysevent_t		*ev;
4702 	sysevent_attr_list_t	*attr = NULL;
4703 	sysevent_value_t	value;
4704 	sysevent_id_t		eid;
4705 
4706 	ev = sysevent_alloc(EC_ZFS, (char *)name, SUNW_KERN_PUB "zfs",
4707 	    SE_SLEEP);
4708 
4709 	value.value_type = SE_DATA_TYPE_STRING;
4710 	value.value.sv_string = spa_name(spa);
4711 	if (sysevent_add_attr(&attr, ZFS_EV_POOL_NAME, &value, SE_SLEEP) != 0)
4712 		goto done;
4713 
4714 	value.value_type = SE_DATA_TYPE_UINT64;
4715 	value.value.sv_uint64 = spa_guid(spa);
4716 	if (sysevent_add_attr(&attr, ZFS_EV_POOL_GUID, &value, SE_SLEEP) != 0)
4717 		goto done;
4718 
4719 	if (vd) {
4720 		value.value_type = SE_DATA_TYPE_UINT64;
4721 		value.value.sv_uint64 = vd->vdev_guid;
4722 		if (sysevent_add_attr(&attr, ZFS_EV_VDEV_GUID, &value,
4723 		    SE_SLEEP) != 0)
4724 			goto done;
4725 
4726 		if (vd->vdev_path) {
4727 			value.value_type = SE_DATA_TYPE_STRING;
4728 			value.value.sv_string = vd->vdev_path;
4729 			if (sysevent_add_attr(&attr, ZFS_EV_VDEV_PATH,
4730 			    &value, SE_SLEEP) != 0)
4731 				goto done;
4732 		}
4733 	}
4734 
4735 	if (sysevent_attach_attributes(ev, attr) != 0)
4736 		goto done;
4737 	attr = NULL;
4738 
4739 	(void) log_sysevent(ev, SE_SLEEP, &eid);
4740 
4741 done:
4742 	if (attr)
4743 		sysevent_free_attr(attr);
4744 	sysevent_free(ev);
4745 #endif
4746 }
4747