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.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or https://opensource.org/licenses/CDDL-1.0.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
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]
23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2012, 2020 by Delphix. All rights reserved.
25 * Copyright (c) 2017, Intel Corporation.
29 * Virtual Device Labels
30 * ---------------------
32 * The vdev label serves several distinct purposes:
34 * 1. Uniquely identify this device as part of a ZFS pool and confirm its
35 * identity within the pool.
37 * 2. Verify that all the devices given in a configuration are present
40 * 3. Determine the uberblock for the pool.
42 * 4. In case of an import operation, determine the configuration of the
43 * toplevel vdev of which it is a part.
45 * 5. If an import operation cannot find all the devices in the pool,
46 * provide enough information to the administrator to determine which
47 * devices are missing.
49 * It is important to note that while the kernel is responsible for writing the
50 * label, it only consumes the information in the first three cases. The
51 * latter information is only consumed in userland when determining the
52 * configuration to import a pool.
58 * Before describing the contents of the label, it's important to understand how
59 * the labels are written and updated with respect to the uberblock.
61 * When the pool configuration is altered, either because it was newly created
62 * or a device was added, we want to update all the labels such that we can deal
63 * with fatal failure at any point. To this end, each disk has two labels which
64 * are updated before and after the uberblock is synced. Assuming we have
65 * labels and an uberblock with the following transaction groups:
68 * +------+ +------+ +------+
70 * | t10 | | t10 | | t10 |
72 * +------+ +------+ +------+
74 * In this stable state, the labels and the uberblock were all updated within
75 * the same transaction group (10). Each label is mirrored and checksummed, so
76 * that we can detect when we fail partway through writing the label.
78 * In order to identify which labels are valid, the labels are written in the
81 * 1. For each vdev, update 'L1' to the new label
82 * 2. Update the uberblock
83 * 3. For each vdev, update 'L2' to the new label
85 * Given arbitrary failure, we can determine the correct label to use based on
86 * the transaction group. If we fail after updating L1 but before updating the
87 * UB, we will notice that L1's transaction group is greater than the uberblock,
88 * so L2 must be valid. If we fail after writing the uberblock but before
89 * writing L2, we will notice that L2's transaction group is less than L1, and
90 * therefore L1 is valid.
92 * Another added complexity is that not every label is updated when the config
93 * is synced. If we add a single device, we do not want to have to re-write
94 * every label for every device in the pool. This means that both L1 and L2 may
95 * be older than the pool uberblock, because the necessary information is stored
102 * The vdev label consists of two distinct parts, and is wrapped within the
103 * vdev_label_t structure. The label includes 8k of padding to permit legacy
104 * VTOC disk labels, but is otherwise ignored.
106 * The first half of the label is a packed nvlist which contains pool wide
107 * properties, per-vdev properties, and configuration information. It is
108 * described in more detail below.
110 * The latter half of the label consists of a redundant array of uberblocks.
111 * These uberblocks are updated whenever a transaction group is committed,
112 * or when the configuration is updated. When a pool is loaded, we scan each
113 * vdev for the 'best' uberblock.
116 * Configuration Information
117 * -------------------------
119 * The nvlist describing the pool and vdev contains the following elements:
121 * version ZFS on-disk version
124 * txg Transaction group in which this label was written
125 * pool_guid Unique identifier for this pool
126 * vdev_tree An nvlist describing vdev tree.
128 * An nvlist of the features necessary for reading the MOS.
130 * Each leaf device label also contains the following:
132 * top_guid Unique ID for top-level vdev in which this is contained
133 * guid Unique ID for the leaf vdev
135 * The 'vs' configuration follows the format described in 'spa_config.c'.
138 #include <sys/zfs_context.h>
140 #include <sys/spa_impl.h>
143 #include <sys/vdev.h>
144 #include <sys/vdev_impl.h>
145 #include <sys/vdev_draid.h>
146 #include <sys/uberblock_impl.h>
147 #include <sys/metaslab.h>
148 #include <sys/metaslab_impl.h>
150 #include <sys/dsl_scan.h>
152 #include <sys/fs/zfs.h>
153 #include <sys/byteorder.h>
154 #include <sys/zfs_bootenv.h>
157 * Basic routines to read and write from a vdev label.
158 * Used throughout the rest of this file.
161 vdev_label_offset(uint64_t psize, int l, uint64_t offset)
163 ASSERT(offset < sizeof (vdev_label_t));
164 ASSERT(P2PHASE_TYPED(psize, sizeof (vdev_label_t), uint64_t) == 0);
166 return (offset + l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ?
167 0 : psize - VDEV_LABELS * sizeof (vdev_label_t)));
171 * Returns back the vdev label associated with the passed in offset.
174 vdev_label_number(uint64_t psize, uint64_t offset)
178 if (offset >= psize - VDEV_LABEL_END_SIZE) {
179 offset -= psize - VDEV_LABEL_END_SIZE;
180 offset += (VDEV_LABELS / 2) * sizeof (vdev_label_t);
182 l = offset / sizeof (vdev_label_t);
183 return (l < VDEV_LABELS ? l : -1);
187 vdev_label_read(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset,
188 uint64_t size, zio_done_func_t *done, void *private, int flags)
191 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE ||
192 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE);
193 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER);
195 zio_nowait(zio_read_phys(zio, vd,
196 vdev_label_offset(vd->vdev_psize, l, offset),
197 size, buf, ZIO_CHECKSUM_LABEL, done, private,
198 ZIO_PRIORITY_SYNC_READ, flags, B_TRUE));
202 vdev_label_write(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset,
203 uint64_t size, zio_done_func_t *done, void *private, int flags)
206 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE ||
207 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE);
208 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER);
210 zio_nowait(zio_write_phys(zio, vd,
211 vdev_label_offset(vd->vdev_psize, l, offset),
212 size, buf, ZIO_CHECKSUM_LABEL, done, private,
213 ZIO_PRIORITY_SYNC_WRITE, flags, B_TRUE));
217 * Generate the nvlist representing this vdev's stats
220 vdev_config_generate_stats(vdev_t *vd, nvlist_t *nv)
226 vs = kmem_alloc(sizeof (*vs), KM_SLEEP);
227 vsx = kmem_alloc(sizeof (*vsx), KM_SLEEP);
229 vdev_get_stats_ex(vd, vs, vsx);
230 fnvlist_add_uint64_array(nv, ZPOOL_CONFIG_VDEV_STATS,
231 (uint64_t *)vs, sizeof (*vs) / sizeof (uint64_t));
234 * Add extended stats into a special extended stats nvlist. This keeps
235 * all the extended stats nicely grouped together. The extended stats
236 * nvlist is then added to the main nvlist.
238 nvx = fnvlist_alloc();
240 /* ZIOs in flight to disk */
241 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_ACTIVE_QUEUE,
242 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_READ]);
244 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_ACTIVE_QUEUE,
245 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_WRITE]);
247 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_ACTIVE_QUEUE,
248 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_READ]);
250 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_ACTIVE_QUEUE,
251 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_WRITE]);
253 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_ACTIVE_QUEUE,
254 vsx->vsx_active_queue[ZIO_PRIORITY_SCRUB]);
256 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_ACTIVE_QUEUE,
257 vsx->vsx_active_queue[ZIO_PRIORITY_TRIM]);
259 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_REBUILD_ACTIVE_QUEUE,
260 vsx->vsx_active_queue[ZIO_PRIORITY_REBUILD]);
263 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_PEND_QUEUE,
264 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_READ]);
266 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_PEND_QUEUE,
267 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_WRITE]);
269 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_PEND_QUEUE,
270 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_READ]);
272 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_PEND_QUEUE,
273 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_WRITE]);
275 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_PEND_QUEUE,
276 vsx->vsx_pend_queue[ZIO_PRIORITY_SCRUB]);
278 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_PEND_QUEUE,
279 vsx->vsx_pend_queue[ZIO_PRIORITY_TRIM]);
281 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_REBUILD_PEND_QUEUE,
282 vsx->vsx_pend_queue[ZIO_PRIORITY_REBUILD]);
285 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_R_LAT_HISTO,
286 vsx->vsx_total_histo[ZIO_TYPE_READ],
287 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_READ]));
289 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_W_LAT_HISTO,
290 vsx->vsx_total_histo[ZIO_TYPE_WRITE],
291 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_WRITE]));
293 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_R_LAT_HISTO,
294 vsx->vsx_disk_histo[ZIO_TYPE_READ],
295 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_READ]));
297 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_W_LAT_HISTO,
298 vsx->vsx_disk_histo[ZIO_TYPE_WRITE],
299 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_WRITE]));
301 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_LAT_HISTO,
302 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ],
303 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ]));
305 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_LAT_HISTO,
306 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE],
307 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE]));
309 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_LAT_HISTO,
310 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ],
311 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ]));
313 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_LAT_HISTO,
314 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE],
315 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE]));
317 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SCRUB_LAT_HISTO,
318 vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB],
319 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB]));
321 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TRIM_LAT_HISTO,
322 vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM],
323 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM]));
325 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_REBUILD_LAT_HISTO,
326 vsx->vsx_queue_histo[ZIO_PRIORITY_REBUILD],
327 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_REBUILD]));
330 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_R_HISTO,
331 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ],
332 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ]));
334 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_W_HISTO,
335 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE],
336 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE]));
338 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_R_HISTO,
339 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ],
340 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ]));
342 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_W_HISTO,
343 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE],
344 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE]));
346 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_SCRUB_HISTO,
347 vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB],
348 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB]));
350 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_TRIM_HISTO,
351 vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM],
352 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM]));
354 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_REBUILD_HISTO,
355 vsx->vsx_ind_histo[ZIO_PRIORITY_REBUILD],
356 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_REBUILD]));
358 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_R_HISTO,
359 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ],
360 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ]));
362 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_W_HISTO,
363 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE],
364 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE]));
366 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_R_HISTO,
367 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ],
368 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ]));
370 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_W_HISTO,
371 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE],
372 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE]));
374 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_SCRUB_HISTO,
375 vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB],
376 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB]));
378 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_TRIM_HISTO,
379 vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM],
380 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM]));
382 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_REBUILD_HISTO,
383 vsx->vsx_agg_histo[ZIO_PRIORITY_REBUILD],
384 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_REBUILD]));
387 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SLOW_IOS, vs->vs_slow_ios);
389 /* Add extended stats nvlist to main nvlist */
390 fnvlist_add_nvlist(nv, ZPOOL_CONFIG_VDEV_STATS_EX, nvx);
393 kmem_free(vs, sizeof (*vs));
394 kmem_free(vsx, sizeof (*vsx));
398 root_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl)
400 spa_t *spa = vd->vdev_spa;
402 if (vd != spa->spa_root_vdev)
405 /* provide either current or previous scan information */
407 if (spa_scan_get_stats(spa, &ps) == 0) {
408 fnvlist_add_uint64_array(nvl,
409 ZPOOL_CONFIG_SCAN_STATS, (uint64_t *)&ps,
410 sizeof (pool_scan_stat_t) / sizeof (uint64_t));
413 pool_removal_stat_t prs;
414 if (spa_removal_get_stats(spa, &prs) == 0) {
415 fnvlist_add_uint64_array(nvl,
416 ZPOOL_CONFIG_REMOVAL_STATS, (uint64_t *)&prs,
417 sizeof (prs) / sizeof (uint64_t));
420 pool_checkpoint_stat_t pcs;
421 if (spa_checkpoint_get_stats(spa, &pcs) == 0) {
422 fnvlist_add_uint64_array(nvl,
423 ZPOOL_CONFIG_CHECKPOINT_STATS, (uint64_t *)&pcs,
424 sizeof (pcs) / sizeof (uint64_t));
429 top_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl)
431 if (vd == vd->vdev_top) {
432 vdev_rebuild_stat_t vrs;
433 if (vdev_rebuild_get_stats(vd, &vrs) == 0) {
434 fnvlist_add_uint64_array(nvl,
435 ZPOOL_CONFIG_REBUILD_STATS, (uint64_t *)&vrs,
436 sizeof (vrs) / sizeof (uint64_t));
442 * Generate the nvlist representing this vdev's config.
445 vdev_config_generate(spa_t *spa, vdev_t *vd, boolean_t getstats,
446 vdev_config_flag_t flags)
449 vdev_indirect_config_t *vic = &vd->vdev_indirect_config;
451 nv = fnvlist_alloc();
453 fnvlist_add_string(nv, ZPOOL_CONFIG_TYPE, vd->vdev_ops->vdev_op_type);
454 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE)))
455 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ID, vd->vdev_id);
456 fnvlist_add_uint64(nv, ZPOOL_CONFIG_GUID, vd->vdev_guid);
458 if (vd->vdev_path != NULL)
459 fnvlist_add_string(nv, ZPOOL_CONFIG_PATH, vd->vdev_path);
461 if (vd->vdev_devid != NULL)
462 fnvlist_add_string(nv, ZPOOL_CONFIG_DEVID, vd->vdev_devid);
464 if (vd->vdev_physpath != NULL)
465 fnvlist_add_string(nv, ZPOOL_CONFIG_PHYS_PATH,
468 if (vd->vdev_enc_sysfs_path != NULL)
469 fnvlist_add_string(nv, ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH,
470 vd->vdev_enc_sysfs_path);
472 if (vd->vdev_fru != NULL)
473 fnvlist_add_string(nv, ZPOOL_CONFIG_FRU, vd->vdev_fru);
475 if (vd->vdev_ops->vdev_op_config_generate != NULL)
476 vd->vdev_ops->vdev_op_config_generate(vd, nv);
478 if (vd->vdev_wholedisk != -1ULL) {
479 fnvlist_add_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK,
483 if (vd->vdev_not_present && !(flags & VDEV_CONFIG_MISSING))
484 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NOT_PRESENT, 1);
486 if (vd->vdev_isspare)
487 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_SPARE, 1);
489 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE)) &&
490 vd == vd->vdev_top) {
491 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_ARRAY,
493 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_SHIFT,
495 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASHIFT, vd->vdev_ashift);
496 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASIZE,
498 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_LOG, vd->vdev_islog);
499 if (vd->vdev_noalloc) {
500 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NONALLOCATING,
505 * Slog devices are removed synchronously so don't
506 * persist the vdev_removing flag to the label.
508 if (vd->vdev_removing && !vd->vdev_islog) {
509 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVING,
513 /* zpool command expects alloc class data */
514 if (getstats && vd->vdev_alloc_bias != VDEV_BIAS_NONE) {
515 const char *bias = NULL;
517 switch (vd->vdev_alloc_bias) {
519 bias = VDEV_ALLOC_BIAS_LOG;
521 case VDEV_BIAS_SPECIAL:
522 bias = VDEV_ALLOC_BIAS_SPECIAL;
524 case VDEV_BIAS_DEDUP:
525 bias = VDEV_ALLOC_BIAS_DEDUP;
528 ASSERT3U(vd->vdev_alloc_bias, ==,
531 fnvlist_add_string(nv, ZPOOL_CONFIG_ALLOCATION_BIAS,
536 if (vd->vdev_dtl_sm != NULL) {
537 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DTL,
538 space_map_object(vd->vdev_dtl_sm));
541 if (vic->vic_mapping_object != 0) {
542 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_OBJECT,
543 vic->vic_mapping_object);
546 if (vic->vic_births_object != 0) {
547 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_BIRTHS,
548 vic->vic_births_object);
551 if (vic->vic_prev_indirect_vdev != UINT64_MAX) {
552 fnvlist_add_uint64(nv, ZPOOL_CONFIG_PREV_INDIRECT_VDEV,
553 vic->vic_prev_indirect_vdev);
557 fnvlist_add_uint64(nv, ZPOOL_CONFIG_CREATE_TXG, vd->vdev_crtxg);
559 if (vd->vdev_expansion_time)
560 fnvlist_add_uint64(nv, ZPOOL_CONFIG_EXPANSION_TIME,
561 vd->vdev_expansion_time);
563 if (flags & VDEV_CONFIG_MOS) {
564 if (vd->vdev_leaf_zap != 0) {
565 ASSERT(vd->vdev_ops->vdev_op_leaf);
566 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_LEAF_ZAP,
570 if (vd->vdev_top_zap != 0) {
571 ASSERT(vd == vd->vdev_top);
572 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_TOP_ZAP,
576 if (vd->vdev_resilver_deferred) {
577 ASSERT(vd->vdev_ops->vdev_op_leaf);
578 ASSERT(spa->spa_resilver_deferred);
579 fnvlist_add_boolean(nv, ZPOOL_CONFIG_RESILVER_DEFER);
584 vdev_config_generate_stats(vd, nv);
586 root_vdev_actions_getprogress(vd, nv);
587 top_vdev_actions_getprogress(vd, nv);
590 * Note: this can be called from open context
591 * (spa_get_stats()), so we need the rwlock to prevent
592 * the mapping from being changed by condensing.
594 rw_enter(&vd->vdev_indirect_rwlock, RW_READER);
595 if (vd->vdev_indirect_mapping != NULL) {
596 ASSERT(vd->vdev_indirect_births != NULL);
597 vdev_indirect_mapping_t *vim =
598 vd->vdev_indirect_mapping;
599 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE,
600 vdev_indirect_mapping_size(vim));
602 rw_exit(&vd->vdev_indirect_rwlock);
603 if (vd->vdev_mg != NULL &&
604 vd->vdev_mg->mg_fragmentation != ZFS_FRAG_INVALID) {
606 * Compute approximately how much memory would be used
607 * for the indirect mapping if this device were to
610 * Note: If the frag metric is invalid, then not
611 * enough metaslabs have been converted to have
614 uint64_t seg_count = 0;
615 uint64_t to_alloc = vd->vdev_stat.vs_alloc;
618 * There are the same number of allocated segments
619 * as free segments, so we will have at least one
620 * entry per free segment. However, small free
621 * segments (smaller than vdev_removal_max_span)
622 * will be combined with adjacent allocated segments
623 * as a single mapping.
625 for (int i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) {
626 if (i + 1 < highbit64(vdev_removal_max_span)
629 vd->vdev_mg->mg_histogram[i] <<
633 vd->vdev_mg->mg_histogram[i];
638 * The maximum length of a mapping is
639 * zfs_remove_max_segment, so we need at least one entry
640 * per zfs_remove_max_segment of allocated data.
642 seg_count += to_alloc / spa_remove_max_segment(spa);
644 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE,
646 sizeof (vdev_indirect_mapping_entry_phys_t));
650 if (!vd->vdev_ops->vdev_op_leaf) {
654 ASSERT(!vd->vdev_ishole);
656 child = kmem_alloc(vd->vdev_children * sizeof (nvlist_t *),
659 for (c = 0; c < vd->vdev_children; c++) {
660 child[c] = vdev_config_generate(spa, vd->vdev_child[c],
664 fnvlist_add_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
665 (const nvlist_t * const *)child, vd->vdev_children);
667 for (c = 0; c < vd->vdev_children; c++)
668 nvlist_free(child[c]);
670 kmem_free(child, vd->vdev_children * sizeof (nvlist_t *));
673 const char *aux = NULL;
675 if (vd->vdev_offline && !vd->vdev_tmpoffline)
676 fnvlist_add_uint64(nv, ZPOOL_CONFIG_OFFLINE, B_TRUE);
677 if (vd->vdev_resilver_txg != 0)
678 fnvlist_add_uint64(nv, ZPOOL_CONFIG_RESILVER_TXG,
679 vd->vdev_resilver_txg);
680 if (vd->vdev_rebuild_txg != 0)
681 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REBUILD_TXG,
682 vd->vdev_rebuild_txg);
683 if (vd->vdev_faulted)
684 fnvlist_add_uint64(nv, ZPOOL_CONFIG_FAULTED, B_TRUE);
685 if (vd->vdev_degraded)
686 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DEGRADED, B_TRUE);
687 if (vd->vdev_removed)
688 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVED, B_TRUE);
689 if (vd->vdev_unspare)
690 fnvlist_add_uint64(nv, ZPOOL_CONFIG_UNSPARE, B_TRUE);
692 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_HOLE, B_TRUE);
694 /* Set the reason why we're FAULTED/DEGRADED. */
695 switch (vd->vdev_stat.vs_aux) {
696 case VDEV_AUX_ERR_EXCEEDED:
697 aux = "err_exceeded";
700 case VDEV_AUX_EXTERNAL:
705 if (aux != NULL && !vd->vdev_tmpoffline) {
706 fnvlist_add_string(nv, ZPOOL_CONFIG_AUX_STATE, aux);
709 * We're healthy - clear any previous AUX_STATE values.
711 if (nvlist_exists(nv, ZPOOL_CONFIG_AUX_STATE))
712 nvlist_remove_all(nv, ZPOOL_CONFIG_AUX_STATE);
715 if (vd->vdev_splitting && vd->vdev_orig_guid != 0LL) {
716 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ORIG_GUID,
725 * Generate a view of the top-level vdevs. If we currently have holes
726 * in the namespace, then generate an array which contains a list of holey
727 * vdevs. Additionally, add the number of top-level children that currently
731 vdev_top_config_generate(spa_t *spa, nvlist_t *config)
733 vdev_t *rvd = spa->spa_root_vdev;
737 array = kmem_alloc(rvd->vdev_children * sizeof (uint64_t), KM_SLEEP);
739 for (c = 0, idx = 0; c < rvd->vdev_children; c++) {
740 vdev_t *tvd = rvd->vdev_child[c];
742 if (tvd->vdev_ishole) {
748 VERIFY(nvlist_add_uint64_array(config, ZPOOL_CONFIG_HOLE_ARRAY,
752 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN,
753 rvd->vdev_children) == 0);
755 kmem_free(array, rvd->vdev_children * sizeof (uint64_t));
759 * Returns the configuration from the label of the given vdev. For vdevs
760 * which don't have a txg value stored on their label (i.e. spares/cache)
761 * or have not been completely initialized (txg = 0) just return
762 * the configuration from the first valid label we find. Otherwise,
763 * find the most up-to-date label that does not exceed the specified
767 vdev_label_read_config(vdev_t *vd, uint64_t txg)
769 spa_t *spa = vd->vdev_spa;
770 nvlist_t *config = NULL;
771 vdev_phys_t *vp[VDEV_LABELS];
772 abd_t *vp_abd[VDEV_LABELS];
773 zio_t *zio[VDEV_LABELS];
774 uint64_t best_txg = 0;
775 uint64_t label_txg = 0;
777 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL |
778 ZIO_FLAG_SPECULATIVE;
780 ASSERT(vd->vdev_validate_thread == curthread ||
781 spa_config_held(spa, SCL_STATE_ALL, RW_WRITER) == SCL_STATE_ALL);
783 if (!vdev_readable(vd))
787 * The label for a dRAID distributed spare is not stored on disk.
788 * Instead it is generated when needed which allows us to bypass
789 * the pipeline when reading the config from the label.
791 if (vd->vdev_ops == &vdev_draid_spare_ops)
792 return (vdev_draid_read_config_spare(vd));
794 for (int l = 0; l < VDEV_LABELS; l++) {
795 vp_abd[l] = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE);
796 vp[l] = abd_to_buf(vp_abd[l]);
800 for (int l = 0; l < VDEV_LABELS; l++) {
801 zio[l] = zio_root(spa, NULL, NULL, flags);
803 vdev_label_read(zio[l], vd, l, vp_abd[l],
804 offsetof(vdev_label_t, vl_vdev_phys), sizeof (vdev_phys_t),
807 for (int l = 0; l < VDEV_LABELS; l++) {
808 nvlist_t *label = NULL;
810 if (zio_wait(zio[l]) == 0 &&
811 nvlist_unpack(vp[l]->vp_nvlist, sizeof (vp[l]->vp_nvlist),
814 * Auxiliary vdevs won't have txg values in their
815 * labels and newly added vdevs may not have been
816 * completely initialized so just return the
817 * configuration from the first valid label we
820 error = nvlist_lookup_uint64(label,
821 ZPOOL_CONFIG_POOL_TXG, &label_txg);
822 if ((error || label_txg == 0) && !config) {
824 for (l++; l < VDEV_LABELS; l++)
827 } else if (label_txg <= txg && label_txg > best_txg) {
828 best_txg = label_txg;
830 config = fnvlist_dup(label);
840 if (config == NULL && !(flags & ZIO_FLAG_TRYHARD)) {
841 flags |= ZIO_FLAG_TRYHARD;
846 * We found a valid label but it didn't pass txg restrictions.
848 if (config == NULL && label_txg != 0) {
849 vdev_dbgmsg(vd, "label discarded as txg is too large "
850 "(%llu > %llu)", (u_longlong_t)label_txg,
854 for (int l = 0; l < VDEV_LABELS; l++) {
862 * Determine if a device is in use. The 'spare_guid' parameter will be filled
863 * in with the device guid if this spare is active elsewhere on the system.
866 vdev_inuse(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason,
867 uint64_t *spare_guid, uint64_t *l2cache_guid)
869 spa_t *spa = vd->vdev_spa;
870 uint64_t state, pool_guid, device_guid, txg, spare_pool;
877 *l2cache_guid = 0ULL;
880 * Read the label, if any, and perform some basic sanity checks.
882 if ((label = vdev_label_read_config(vd, -1ULL)) == NULL)
885 (void) nvlist_lookup_uint64(label, ZPOOL_CONFIG_CREATE_TXG,
888 if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_STATE,
890 nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID,
891 &device_guid) != 0) {
896 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
897 (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID,
899 nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG,
908 * Check to see if this device indeed belongs to the pool it claims to
909 * be a part of. The only way this is allowed is if the device is a hot
910 * spare (which we check for later on).
912 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
913 !spa_guid_exists(pool_guid, device_guid) &&
914 !spa_spare_exists(device_guid, NULL, NULL) &&
915 !spa_l2cache_exists(device_guid, NULL))
919 * If the transaction group is zero, then this an initialized (but
920 * unused) label. This is only an error if the create transaction
921 * on-disk is the same as the one we're using now, in which case the
922 * user has attempted to add the same vdev multiple times in the same
925 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
926 txg == 0 && vdtxg == crtxg)
930 * Check to see if this is a spare device. We do an explicit check for
931 * spa_has_spare() here because it may be on our pending list of spares
934 if (spa_spare_exists(device_guid, &spare_pool, NULL) ||
935 spa_has_spare(spa, device_guid)) {
937 *spare_guid = device_guid;
940 case VDEV_LABEL_CREATE:
943 case VDEV_LABEL_REPLACE:
944 return (!spa_has_spare(spa, device_guid) ||
947 case VDEV_LABEL_SPARE:
948 return (spa_has_spare(spa, device_guid));
955 * Check to see if this is an l2cache device.
957 if (spa_l2cache_exists(device_guid, NULL) ||
958 spa_has_l2cache(spa, device_guid)) {
960 *l2cache_guid = device_guid;
963 case VDEV_LABEL_CREATE:
966 case VDEV_LABEL_REPLACE:
967 return (!spa_has_l2cache(spa, device_guid));
969 case VDEV_LABEL_L2CACHE:
970 return (spa_has_l2cache(spa, device_guid));
977 * We can't rely on a pool's state if it's been imported
978 * read-only. Instead we look to see if the pools is marked
979 * read-only in the namespace and set the state to active.
981 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
982 (spa = spa_by_guid(pool_guid, device_guid)) != NULL &&
983 spa_mode(spa) == SPA_MODE_READ)
984 state = POOL_STATE_ACTIVE;
987 * If the device is marked ACTIVE, then this device is in use by another
988 * pool on the system.
990 return (state == POOL_STATE_ACTIVE);
994 * Initialize a vdev label. We check to make sure each leaf device is not in
995 * use, and writable. We put down an initial label which we will later
996 * overwrite with a complete label. Note that it's important to do this
997 * sequentially, not in parallel, so that we catch cases of multiple use of the
998 * same leaf vdev in the vdev we're creating -- e.g. mirroring a disk with
1002 vdev_label_init(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason)
1004 spa_t *spa = vd->vdev_spa;
1015 uint64_t spare_guid = 0, l2cache_guid = 0;
1016 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL;
1018 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1020 for (int c = 0; c < vd->vdev_children; c++)
1021 if ((error = vdev_label_init(vd->vdev_child[c],
1022 crtxg, reason)) != 0)
1025 /* Track the creation time for this vdev */
1026 vd->vdev_crtxg = crtxg;
1028 if (!vd->vdev_ops->vdev_op_leaf || !spa_writeable(spa))
1032 * Dead vdevs cannot be initialized.
1034 if (vdev_is_dead(vd))
1035 return (SET_ERROR(EIO));
1038 * Determine if the vdev is in use.
1040 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPLIT &&
1041 vdev_inuse(vd, crtxg, reason, &spare_guid, &l2cache_guid))
1042 return (SET_ERROR(EBUSY));
1045 * If this is a request to add or replace a spare or l2cache device
1046 * that is in use elsewhere on the system, then we must update the
1047 * guid (which was initialized to a random value) to reflect the
1048 * actual GUID (which is shared between multiple pools).
1050 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_L2CACHE &&
1051 spare_guid != 0ULL) {
1052 uint64_t guid_delta = spare_guid - vd->vdev_guid;
1054 vd->vdev_guid += guid_delta;
1056 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent)
1057 pvd->vdev_guid_sum += guid_delta;
1060 * If this is a replacement, then we want to fallthrough to the
1061 * rest of the code. If we're adding a spare, then it's already
1062 * labeled appropriately and we can just return.
1064 if (reason == VDEV_LABEL_SPARE)
1066 ASSERT(reason == VDEV_LABEL_REPLACE ||
1067 reason == VDEV_LABEL_SPLIT);
1070 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPARE &&
1071 l2cache_guid != 0ULL) {
1072 uint64_t guid_delta = l2cache_guid - vd->vdev_guid;
1074 vd->vdev_guid += guid_delta;
1076 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent)
1077 pvd->vdev_guid_sum += guid_delta;
1080 * If this is a replacement, then we want to fallthrough to the
1081 * rest of the code. If we're adding an l2cache, then it's
1082 * already labeled appropriately and we can just return.
1084 if (reason == VDEV_LABEL_L2CACHE)
1086 ASSERT(reason == VDEV_LABEL_REPLACE);
1090 * Initialize its label.
1092 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE);
1093 abd_zero(vp_abd, sizeof (vdev_phys_t));
1094 vp = abd_to_buf(vp_abd);
1097 * Generate a label describing the pool and our top-level vdev.
1098 * We mark it as being from txg 0 to indicate that it's not
1099 * really part of an active pool just yet. The labels will
1100 * be written again with a meaningful txg by spa_sync().
1102 if (reason == VDEV_LABEL_SPARE ||
1103 (reason == VDEV_LABEL_REMOVE && vd->vdev_isspare)) {
1105 * For inactive hot spares, we generate a special label that
1106 * identifies as a mutually shared hot spare. We write the
1107 * label if we are adding a hot spare, or if we are removing an
1108 * active hot spare (in which case we want to revert the
1111 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1113 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION,
1114 spa_version(spa)) == 0);
1115 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE,
1116 POOL_STATE_SPARE) == 0);
1117 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID,
1118 vd->vdev_guid) == 0);
1119 } else if (reason == VDEV_LABEL_L2CACHE ||
1120 (reason == VDEV_LABEL_REMOVE && vd->vdev_isl2cache)) {
1122 * For level 2 ARC devices, add a special label.
1124 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1126 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION,
1127 spa_version(spa)) == 0);
1128 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE,
1129 POOL_STATE_L2CACHE) == 0);
1130 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID,
1131 vd->vdev_guid) == 0);
1133 uint64_t txg = 0ULL;
1135 if (reason == VDEV_LABEL_SPLIT)
1136 txg = spa->spa_uberblock.ub_txg;
1137 label = spa_config_generate(spa, vd, txg, B_FALSE);
1140 * Add our creation time. This allows us to detect multiple
1141 * vdev uses as described above, and automatically expires if we
1144 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_CREATE_TXG,
1148 buf = vp->vp_nvlist;
1149 buflen = sizeof (vp->vp_nvlist);
1151 error = nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP);
1155 /* EFAULT means nvlist_pack ran out of room */
1156 return (SET_ERROR(error == EFAULT ? ENAMETOOLONG : EINVAL));
1160 * Initialize uberblock template.
1162 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_RING, B_TRUE);
1163 abd_zero(ub_abd, VDEV_UBERBLOCK_RING);
1164 abd_copy_from_buf(ub_abd, &spa->spa_uberblock, sizeof (uberblock_t));
1165 ub = abd_to_buf(ub_abd);
1168 /* Initialize the 2nd padding area. */
1169 bootenv = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE);
1170 abd_zero(bootenv, VDEV_PAD_SIZE);
1173 * Write everything in parallel.
1176 zio = zio_root(spa, NULL, NULL, flags);
1178 for (int l = 0; l < VDEV_LABELS; l++) {
1180 vdev_label_write(zio, vd, l, vp_abd,
1181 offsetof(vdev_label_t, vl_vdev_phys),
1182 sizeof (vdev_phys_t), NULL, NULL, flags);
1185 * Skip the 1st padding area.
1186 * Zero out the 2nd padding area where it might have
1187 * left over data from previous filesystem format.
1189 vdev_label_write(zio, vd, l, bootenv,
1190 offsetof(vdev_label_t, vl_be),
1191 VDEV_PAD_SIZE, NULL, NULL, flags);
1193 vdev_label_write(zio, vd, l, ub_abd,
1194 offsetof(vdev_label_t, vl_uberblock),
1195 VDEV_UBERBLOCK_RING, NULL, NULL, flags);
1198 error = zio_wait(zio);
1200 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) {
1201 flags |= ZIO_FLAG_TRYHARD;
1211 * If this vdev hasn't been previously identified as a spare, then we
1212 * mark it as such only if a) we are labeling it as a spare, or b) it
1213 * exists as a spare elsewhere in the system. Do the same for
1214 * level 2 ARC devices.
1216 if (error == 0 && !vd->vdev_isspare &&
1217 (reason == VDEV_LABEL_SPARE ||
1218 spa_spare_exists(vd->vdev_guid, NULL, NULL)))
1221 if (error == 0 && !vd->vdev_isl2cache &&
1222 (reason == VDEV_LABEL_L2CACHE ||
1223 spa_l2cache_exists(vd->vdev_guid, NULL)))
1224 spa_l2cache_add(vd);
1230 * Done callback for vdev_label_read_bootenv_impl. If this is the first
1231 * callback to finish, store our abd in the callback pointer. Otherwise, we
1232 * just free our abd and return.
1235 vdev_label_read_bootenv_done(zio_t *zio)
1237 zio_t *rio = zio->io_private;
1238 abd_t **cbp = rio->io_private;
1240 ASSERT3U(zio->io_size, ==, VDEV_PAD_SIZE);
1242 if (zio->io_error == 0) {
1243 mutex_enter(&rio->io_lock);
1245 /* Will free this buffer in vdev_label_read_bootenv. */
1248 abd_free(zio->io_abd);
1250 mutex_exit(&rio->io_lock);
1252 abd_free(zio->io_abd);
1257 vdev_label_read_bootenv_impl(zio_t *zio, vdev_t *vd, int flags)
1259 for (int c = 0; c < vd->vdev_children; c++)
1260 vdev_label_read_bootenv_impl(zio, vd->vdev_child[c], flags);
1263 * We just use the first label that has a correct checksum; the
1264 * bootloader should have rewritten them all to be the same on boot,
1265 * and any changes we made since boot have been the same across all
1268 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd)) {
1269 for (int l = 0; l < VDEV_LABELS; l++) {
1270 vdev_label_read(zio, vd, l,
1271 abd_alloc_linear(VDEV_PAD_SIZE, B_FALSE),
1272 offsetof(vdev_label_t, vl_be), VDEV_PAD_SIZE,
1273 vdev_label_read_bootenv_done, zio, flags);
1279 vdev_label_read_bootenv(vdev_t *rvd, nvlist_t *bootenv)
1282 spa_t *spa = rvd->vdev_spa;
1284 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL |
1285 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD;
1288 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1290 zio_t *zio = zio_root(spa, NULL, &abd, flags);
1291 vdev_label_read_bootenv_impl(zio, rvd, flags);
1292 int err = zio_wait(zio);
1296 vdev_boot_envblock_t *vbe = abd_to_buf(abd);
1298 vbe->vbe_version = ntohll(vbe->vbe_version);
1299 switch (vbe->vbe_version) {
1302 * if we have textual data in vbe_bootenv, create nvlist
1303 * with key "envmap".
1305 fnvlist_add_uint64(bootenv, BOOTENV_VERSION, VB_RAW);
1306 vbe->vbe_bootenv[sizeof (vbe->vbe_bootenv) - 1] = '\0';
1307 fnvlist_add_string(bootenv, GRUB_ENVMAP,
1312 err = nvlist_unpack(vbe->vbe_bootenv,
1313 sizeof (vbe->vbe_bootenv), &config, 0);
1315 fnvlist_merge(bootenv, config);
1316 nvlist_free(config);
1321 /* Check for FreeBSD zfs bootonce command string */
1322 buf = abd_to_buf(abd);
1324 fnvlist_add_uint64(bootenv, BOOTENV_VERSION,
1328 fnvlist_add_string(bootenv, FREEBSD_BOOTONCE, buf);
1332 * abd was allocated in vdev_label_read_bootenv_impl()
1336 * If we managed to read any successfully,
1345 vdev_label_write_bootenv(vdev_t *vd, nvlist_t *env)
1348 spa_t *spa = vd->vdev_spa;
1349 vdev_boot_envblock_t *bootenv;
1350 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL;
1356 error = nvlist_size(env, &nvsize, NV_ENCODE_XDR);
1358 return (SET_ERROR(error));
1360 if (nvsize >= sizeof (bootenv->vbe_bootenv)) {
1361 return (SET_ERROR(E2BIG));
1364 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1367 for (int c = 0; c < vd->vdev_children; c++) {
1370 child_err = vdev_label_write_bootenv(vd->vdev_child[c], env);
1372 * As long as any of the disks managed to write all of their
1373 * labels successfully, return success.
1379 if (!vd->vdev_ops->vdev_op_leaf || vdev_is_dead(vd) ||
1380 !vdev_writeable(vd)) {
1383 ASSERT3U(sizeof (*bootenv), ==, VDEV_PAD_SIZE);
1384 abd_t *abd = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE);
1385 abd_zero(abd, VDEV_PAD_SIZE);
1387 bootenv = abd_borrow_buf_copy(abd, VDEV_PAD_SIZE);
1388 nvbuf = bootenv->vbe_bootenv;
1389 nvsize = sizeof (bootenv->vbe_bootenv);
1391 bootenv->vbe_version = fnvlist_lookup_uint64(env, BOOTENV_VERSION);
1392 switch (bootenv->vbe_version) {
1394 if (nvlist_lookup_string(env, GRUB_ENVMAP, &tmp) == 0) {
1395 (void) strlcpy(bootenv->vbe_bootenv, tmp, nvsize);
1401 error = nvlist_pack(env, &nvbuf, &nvsize, NV_ENCODE_XDR,
1411 bootenv->vbe_version = htonll(bootenv->vbe_version);
1412 abd_return_buf_copy(abd, bootenv, VDEV_PAD_SIZE);
1415 return (SET_ERROR(error));
1419 zio = zio_root(spa, NULL, NULL, flags);
1420 for (int l = 0; l < VDEV_LABELS; l++) {
1421 vdev_label_write(zio, vd, l, abd,
1422 offsetof(vdev_label_t, vl_be),
1423 VDEV_PAD_SIZE, NULL, NULL, flags);
1426 error = zio_wait(zio);
1427 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) {
1428 flags |= ZIO_FLAG_TRYHARD;
1437 * ==========================================================================
1438 * uberblock load/sync
1439 * ==========================================================================
1443 * Consider the following situation: txg is safely synced to disk. We've
1444 * written the first uberblock for txg + 1, and then we lose power. When we
1445 * come back up, we fail to see the uberblock for txg + 1 because, say,
1446 * it was on a mirrored device and the replica to which we wrote txg + 1
1447 * is now offline. If we then make some changes and sync txg + 1, and then
1448 * the missing replica comes back, then for a few seconds we'll have two
1449 * conflicting uberblocks on disk with the same txg. The solution is simple:
1450 * among uberblocks with equal txg, choose the one with the latest timestamp.
1453 vdev_uberblock_compare(const uberblock_t *ub1, const uberblock_t *ub2)
1455 int cmp = TREE_CMP(ub1->ub_txg, ub2->ub_txg);
1460 cmp = TREE_CMP(ub1->ub_timestamp, ub2->ub_timestamp);
1465 * If MMP_VALID(ub) && MMP_SEQ_VALID(ub) then the host has an MMP-aware
1466 * ZFS, e.g. OpenZFS >= 0.7.
1468 * If one ub has MMP and the other does not, they were written by
1469 * different hosts, which matters for MMP. So we treat no MMP/no SEQ as
1472 * Since timestamp and txg are the same if we get this far, either is
1473 * acceptable for importing the pool.
1475 unsigned int seq1 = 0;
1476 unsigned int seq2 = 0;
1478 if (MMP_VALID(ub1) && MMP_SEQ_VALID(ub1))
1479 seq1 = MMP_SEQ(ub1);
1481 if (MMP_VALID(ub2) && MMP_SEQ_VALID(ub2))
1482 seq2 = MMP_SEQ(ub2);
1484 return (TREE_CMP(seq1, seq2));
1488 uberblock_t *ubl_ubbest; /* Best uberblock */
1489 vdev_t *ubl_vd; /* vdev associated with the above */
1493 vdev_uberblock_load_done(zio_t *zio)
1495 vdev_t *vd = zio->io_vd;
1496 spa_t *spa = zio->io_spa;
1497 zio_t *rio = zio->io_private;
1498 uberblock_t *ub = abd_to_buf(zio->io_abd);
1499 struct ubl_cbdata *cbp = rio->io_private;
1501 ASSERT3U(zio->io_size, ==, VDEV_UBERBLOCK_SIZE(vd));
1503 if (zio->io_error == 0 && uberblock_verify(ub) == 0) {
1504 mutex_enter(&rio->io_lock);
1505 if (ub->ub_txg <= spa->spa_load_max_txg &&
1506 vdev_uberblock_compare(ub, cbp->ubl_ubbest) > 0) {
1508 * Keep track of the vdev in which this uberblock
1509 * was found. We will use this information later
1510 * to obtain the config nvlist associated with
1513 *cbp->ubl_ubbest = *ub;
1516 mutex_exit(&rio->io_lock);
1519 abd_free(zio->io_abd);
1523 vdev_uberblock_load_impl(zio_t *zio, vdev_t *vd, int flags,
1524 struct ubl_cbdata *cbp)
1526 for (int c = 0; c < vd->vdev_children; c++)
1527 vdev_uberblock_load_impl(zio, vd->vdev_child[c], flags, cbp);
1529 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd) &&
1530 vd->vdev_ops != &vdev_draid_spare_ops) {
1531 for (int l = 0; l < VDEV_LABELS; l++) {
1532 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) {
1533 vdev_label_read(zio, vd, l,
1534 abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd),
1535 B_TRUE), VDEV_UBERBLOCK_OFFSET(vd, n),
1536 VDEV_UBERBLOCK_SIZE(vd),
1537 vdev_uberblock_load_done, zio, flags);
1544 * Reads the 'best' uberblock from disk along with its associated
1545 * configuration. First, we read the uberblock array of each label of each
1546 * vdev, keeping track of the uberblock with the highest txg in each array.
1547 * Then, we read the configuration from the same vdev as the best uberblock.
1550 vdev_uberblock_load(vdev_t *rvd, uberblock_t *ub, nvlist_t **config)
1553 spa_t *spa = rvd->vdev_spa;
1554 struct ubl_cbdata cb;
1555 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL |
1556 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD;
1561 memset(ub, 0, sizeof (uberblock_t));
1567 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1568 zio = zio_root(spa, NULL, &cb, flags);
1569 vdev_uberblock_load_impl(zio, rvd, flags, &cb);
1570 (void) zio_wait(zio);
1573 * It's possible that the best uberblock was discovered on a label
1574 * that has a configuration which was written in a future txg.
1575 * Search all labels on this vdev to find the configuration that
1576 * matches the txg for our uberblock.
1578 if (cb.ubl_vd != NULL) {
1579 vdev_dbgmsg(cb.ubl_vd, "best uberblock found for spa %s. "
1580 "txg %llu", spa->spa_name, (u_longlong_t)ub->ub_txg);
1582 *config = vdev_label_read_config(cb.ubl_vd, ub->ub_txg);
1583 if (*config == NULL && spa->spa_extreme_rewind) {
1584 vdev_dbgmsg(cb.ubl_vd, "failed to read label config. "
1585 "Trying again without txg restrictions.");
1586 *config = vdev_label_read_config(cb.ubl_vd, UINT64_MAX);
1588 if (*config == NULL) {
1589 vdev_dbgmsg(cb.ubl_vd, "failed to read label config");
1592 spa_config_exit(spa, SCL_ALL, FTAG);
1596 * For use when a leaf vdev is expanded.
1597 * The location of labels 2 and 3 changed, and at the new location the
1598 * uberblock rings are either empty or contain garbage. The sync will write
1599 * new configs there because the vdev is dirty, but expansion also needs the
1600 * uberblock rings copied. Read them from label 0 which did not move.
1602 * Since the point is to populate labels {2,3} with valid uberblocks,
1603 * we zero uberblocks we fail to read or which are not valid.
1607 vdev_copy_uberblocks(vdev_t *vd)
1611 int locks = (SCL_L2ARC | SCL_ZIO);
1612 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL |
1613 ZIO_FLAG_SPECULATIVE;
1615 ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_READER) ==
1617 ASSERT(vd->vdev_ops->vdev_op_leaf);
1620 * No uberblocks are stored on distributed spares, they may be
1621 * safely skipped when expanding a leaf vdev.
1623 if (vd->vdev_ops == &vdev_draid_spare_ops)
1626 spa_config_enter(vd->vdev_spa, locks, FTAG, RW_READER);
1628 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), B_TRUE);
1630 write_zio = zio_root(vd->vdev_spa, NULL, NULL, flags);
1631 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) {
1632 const int src_label = 0;
1635 zio = zio_root(vd->vdev_spa, NULL, NULL, flags);
1636 vdev_label_read(zio, vd, src_label, ub_abd,
1637 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd),
1640 if (zio_wait(zio) || uberblock_verify(abd_to_buf(ub_abd)))
1641 abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd));
1643 for (int l = 2; l < VDEV_LABELS; l++)
1644 vdev_label_write(write_zio, vd, l, ub_abd,
1645 VDEV_UBERBLOCK_OFFSET(vd, n),
1646 VDEV_UBERBLOCK_SIZE(vd), NULL, NULL,
1647 flags | ZIO_FLAG_DONT_PROPAGATE);
1649 (void) zio_wait(write_zio);
1651 spa_config_exit(vd->vdev_spa, locks, FTAG);
1657 * On success, increment root zio's count of good writes.
1658 * We only get credit for writes to known-visible vdevs; see spa_vdev_add().
1661 vdev_uberblock_sync_done(zio_t *zio)
1663 uint64_t *good_writes = zio->io_private;
1665 if (zio->io_error == 0 && zio->io_vd->vdev_top->vdev_ms_array != 0)
1666 atomic_inc_64(good_writes);
1670 * Write the uberblock to all labels of all leaves of the specified vdev.
1673 vdev_uberblock_sync(zio_t *zio, uint64_t *good_writes,
1674 uberblock_t *ub, vdev_t *vd, int flags)
1676 for (uint64_t c = 0; c < vd->vdev_children; c++) {
1677 vdev_uberblock_sync(zio, good_writes,
1678 ub, vd->vdev_child[c], flags);
1681 if (!vd->vdev_ops->vdev_op_leaf)
1684 if (!vdev_writeable(vd))
1688 * There's no need to write uberblocks to a distributed spare, they
1689 * are already stored on all the leaves of the parent dRAID. For
1690 * this same reason vdev_uberblock_load_impl() skips distributed
1691 * spares when reading uberblocks.
1693 if (vd->vdev_ops == &vdev_draid_spare_ops)
1696 /* If the vdev was expanded, need to copy uberblock rings. */
1697 if (vd->vdev_state == VDEV_STATE_HEALTHY &&
1698 vd->vdev_copy_uberblocks == B_TRUE) {
1699 vdev_copy_uberblocks(vd);
1700 vd->vdev_copy_uberblocks = B_FALSE;
1703 int m = spa_multihost(vd->vdev_spa) ? MMP_BLOCKS_PER_LABEL : 0;
1704 int n = ub->ub_txg % (VDEV_UBERBLOCK_COUNT(vd) - m);
1706 /* Copy the uberblock_t into the ABD */
1707 abd_t *ub_abd = abd_alloc_for_io(VDEV_UBERBLOCK_SIZE(vd), B_TRUE);
1708 abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd));
1709 abd_copy_from_buf(ub_abd, ub, sizeof (uberblock_t));
1711 for (int l = 0; l < VDEV_LABELS; l++)
1712 vdev_label_write(zio, vd, l, ub_abd,
1713 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd),
1714 vdev_uberblock_sync_done, good_writes,
1715 flags | ZIO_FLAG_DONT_PROPAGATE);
1720 /* Sync the uberblocks to all vdevs in svd[] */
1722 vdev_uberblock_sync_list(vdev_t **svd, int svdcount, uberblock_t *ub, int flags)
1724 spa_t *spa = svd[0]->vdev_spa;
1726 uint64_t good_writes = 0;
1728 zio = zio_root(spa, NULL, NULL, flags);
1730 for (int v = 0; v < svdcount; v++)
1731 vdev_uberblock_sync(zio, &good_writes, ub, svd[v], flags);
1733 (void) zio_wait(zio);
1736 * Flush the uberblocks to disk. This ensures that the odd labels
1737 * are no longer needed (because the new uberblocks and the even
1738 * labels are safely on disk), so it is safe to overwrite them.
1740 zio = zio_root(spa, NULL, NULL, flags);
1742 for (int v = 0; v < svdcount; v++) {
1743 if (vdev_writeable(svd[v])) {
1744 zio_flush(zio, svd[v]);
1748 (void) zio_wait(zio);
1750 return (good_writes >= 1 ? 0 : EIO);
1754 * On success, increment the count of good writes for our top-level vdev.
1757 vdev_label_sync_done(zio_t *zio)
1759 uint64_t *good_writes = zio->io_private;
1761 if (zio->io_error == 0)
1762 atomic_inc_64(good_writes);
1766 * If there weren't enough good writes, indicate failure to the parent.
1769 vdev_label_sync_top_done(zio_t *zio)
1771 uint64_t *good_writes = zio->io_private;
1773 if (*good_writes == 0)
1774 zio->io_error = SET_ERROR(EIO);
1776 kmem_free(good_writes, sizeof (uint64_t));
1780 * We ignore errors for log and cache devices, simply free the private data.
1783 vdev_label_sync_ignore_done(zio_t *zio)
1785 kmem_free(zio->io_private, sizeof (uint64_t));
1789 * Write all even or odd labels to all leaves of the specified vdev.
1792 vdev_label_sync(zio_t *zio, uint64_t *good_writes,
1793 vdev_t *vd, int l, uint64_t txg, int flags)
1801 for (int c = 0; c < vd->vdev_children; c++) {
1802 vdev_label_sync(zio, good_writes,
1803 vd->vdev_child[c], l, txg, flags);
1806 if (!vd->vdev_ops->vdev_op_leaf)
1809 if (!vdev_writeable(vd))
1813 * The top-level config never needs to be written to a distributed
1814 * spare. When read vdev_dspare_label_read_config() will generate
1815 * the config for the vdev_label_read_config().
1817 if (vd->vdev_ops == &vdev_draid_spare_ops)
1821 * Generate a label describing the top-level config to which we belong.
1823 label = spa_config_generate(vd->vdev_spa, vd, txg, B_FALSE);
1825 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE);
1826 abd_zero(vp_abd, sizeof (vdev_phys_t));
1827 vp = abd_to_buf(vp_abd);
1829 buf = vp->vp_nvlist;
1830 buflen = sizeof (vp->vp_nvlist);
1832 if (!nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP)) {
1833 for (; l < VDEV_LABELS; l += 2) {
1834 vdev_label_write(zio, vd, l, vp_abd,
1835 offsetof(vdev_label_t, vl_vdev_phys),
1836 sizeof (vdev_phys_t),
1837 vdev_label_sync_done, good_writes,
1838 flags | ZIO_FLAG_DONT_PROPAGATE);
1847 vdev_label_sync_list(spa_t *spa, int l, uint64_t txg, int flags)
1849 list_t *dl = &spa->spa_config_dirty_list;
1855 * Write the new labels to disk.
1857 zio = zio_root(spa, NULL, NULL, flags);
1859 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) {
1860 uint64_t *good_writes;
1862 ASSERT(!vd->vdev_ishole);
1864 good_writes = kmem_zalloc(sizeof (uint64_t), KM_SLEEP);
1865 zio_t *vio = zio_null(zio, spa, NULL,
1866 (vd->vdev_islog || vd->vdev_aux != NULL) ?
1867 vdev_label_sync_ignore_done : vdev_label_sync_top_done,
1868 good_writes, flags);
1869 vdev_label_sync(vio, good_writes, vd, l, txg, flags);
1873 error = zio_wait(zio);
1876 * Flush the new labels to disk.
1878 zio = zio_root(spa, NULL, NULL, flags);
1880 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd))
1883 (void) zio_wait(zio);
1889 * Sync the uberblock and any changes to the vdev configuration.
1891 * The order of operations is carefully crafted to ensure that
1892 * if the system panics or loses power at any time, the state on disk
1893 * is still transactionally consistent. The in-line comments below
1894 * describe the failure semantics at each stage.
1896 * Moreover, vdev_config_sync() is designed to be idempotent: if it fails
1897 * at any time, you can just call it again, and it will resume its work.
1900 vdev_config_sync(vdev_t **svd, int svdcount, uint64_t txg)
1902 spa_t *spa = svd[0]->vdev_spa;
1903 uberblock_t *ub = &spa->spa_uberblock;
1905 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL;
1907 ASSERT(svdcount != 0);
1910 * Normally, we don't want to try too hard to write every label and
1911 * uberblock. If there is a flaky disk, we don't want the rest of the
1912 * sync process to block while we retry. But if we can't write a
1913 * single label out, we should retry with ZIO_FLAG_TRYHARD before
1914 * bailing out and declaring the pool faulted.
1917 if ((flags & ZIO_FLAG_TRYHARD) != 0)
1919 flags |= ZIO_FLAG_TRYHARD;
1922 ASSERT(ub->ub_txg <= txg);
1925 * If this isn't a resync due to I/O errors,
1926 * and nothing changed in this transaction group,
1927 * and the vdev configuration hasn't changed,
1928 * then there's nothing to do.
1930 if (ub->ub_txg < txg) {
1931 boolean_t changed = uberblock_update(ub, spa->spa_root_vdev,
1932 txg, spa->spa_mmp.mmp_delay);
1934 if (!changed && list_is_empty(&spa->spa_config_dirty_list))
1938 if (txg > spa_freeze_txg(spa))
1941 ASSERT(txg <= spa->spa_final_txg);
1944 * Flush the write cache of every disk that's been written to
1945 * in this transaction group. This ensures that all blocks
1946 * written in this txg will be committed to stable storage
1947 * before any uberblock that references them.
1949 zio_t *zio = zio_root(spa, NULL, NULL, flags);
1952 txg_list_head(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)); vd != NULL;
1953 vd = txg_list_next(&spa->spa_vdev_txg_list, vd, TXG_CLEAN(txg)))
1956 (void) zio_wait(zio);
1959 * Sync out the even labels (L0, L2) for every dirty vdev. If the
1960 * system dies in the middle of this process, that's OK: all of the
1961 * even labels that made it to disk will be newer than any uberblock,
1962 * and will therefore be considered invalid. The odd labels (L1, L3),
1963 * which have not yet been touched, will still be valid. We flush
1964 * the new labels to disk to ensure that all even-label updates
1965 * are committed to stable storage before the uberblock update.
1967 if ((error = vdev_label_sync_list(spa, 0, txg, flags)) != 0) {
1968 if ((flags & ZIO_FLAG_TRYHARD) != 0) {
1969 zfs_dbgmsg("vdev_label_sync_list() returned error %d "
1970 "for pool '%s' when syncing out the even labels "
1971 "of dirty vdevs", error, spa_name(spa));
1977 * Sync the uberblocks to all vdevs in svd[].
1978 * If the system dies in the middle of this step, there are two cases
1979 * to consider, and the on-disk state is consistent either way:
1981 * (1) If none of the new uberblocks made it to disk, then the
1982 * previous uberblock will be the newest, and the odd labels
1983 * (which had not yet been touched) will be valid with respect
1984 * to that uberblock.
1986 * (2) If one or more new uberblocks made it to disk, then they
1987 * will be the newest, and the even labels (which had all
1988 * been successfully committed) will be valid with respect
1989 * to the new uberblocks.
1991 if ((error = vdev_uberblock_sync_list(svd, svdcount, ub, flags)) != 0) {
1992 if ((flags & ZIO_FLAG_TRYHARD) != 0) {
1993 zfs_dbgmsg("vdev_uberblock_sync_list() returned error "
1994 "%d for pool '%s'", error, spa_name(spa));
1999 if (spa_multihost(spa))
2000 mmp_update_uberblock(spa, ub);
2003 * Sync out odd labels for every dirty vdev. If the system dies
2004 * in the middle of this process, the even labels and the new
2005 * uberblocks will suffice to open the pool. The next time
2006 * the pool is opened, the first thing we'll do -- before any
2007 * user data is modified -- is mark every vdev dirty so that
2008 * all labels will be brought up to date. We flush the new labels
2009 * to disk to ensure that all odd-label updates are committed to
2010 * stable storage before the next transaction group begins.
2012 if ((error = vdev_label_sync_list(spa, 1, txg, flags)) != 0) {
2013 if ((flags & ZIO_FLAG_TRYHARD) != 0) {
2014 zfs_dbgmsg("vdev_label_sync_list() returned error %d "
2015 "for pool '%s' when syncing out the odd labels of "
2016 "dirty vdevs", error, spa_name(spa));