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