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 https://opensource.org/licenses/CDDL-1.0.
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_raidz.h>
146 #include <sys/vdev_draid.h>
147 #include <sys/uberblock_impl.h>
148 #include <sys/metaslab.h>
149 #include <sys/metaslab_impl.h>
150 #include <sys/zio.h>
151 #include <sys/dsl_scan.h>
152 #include <sys/abd.h>
153 #include <sys/fs/zfs.h>
154 #include <sys/byteorder.h>
155 #include <sys/zfs_bootenv.h>
156
157 /*
158 * Basic routines to read and write from a vdev label.
159 * Used throughout the rest of this file.
160 */
161 uint64_t
vdev_label_offset(uint64_t psize,int l,uint64_t offset)162 vdev_label_offset(uint64_t psize, int l, uint64_t offset)
163 {
164 ASSERT(offset < sizeof (vdev_label_t));
165 ASSERT(P2PHASE_TYPED(psize, sizeof (vdev_label_t), uint64_t) == 0);
166
167 return (offset + l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ?
168 0 : psize - VDEV_LABELS * sizeof (vdev_label_t)));
169 }
170
171 /*
172 * Returns back the vdev label associated with the passed in offset.
173 */
174 int
vdev_label_number(uint64_t psize,uint64_t offset)175 vdev_label_number(uint64_t psize, uint64_t offset)
176 {
177 int l;
178
179 if (offset >= psize - VDEV_LABEL_END_SIZE) {
180 offset -= psize - VDEV_LABEL_END_SIZE;
181 offset += (VDEV_LABELS / 2) * sizeof (vdev_label_t);
182 }
183 l = offset / sizeof (vdev_label_t);
184 return (l < VDEV_LABELS ? l : -1);
185 }
186
187 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)188 vdev_label_read(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset,
189 uint64_t size, zio_done_func_t *done, void *private, int flags)
190 {
191 ASSERT(
192 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE ||
193 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE);
194 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER);
195
196 zio_nowait(zio_read_phys(zio, vd,
197 vdev_label_offset(vd->vdev_psize, l, offset),
198 size, buf, ZIO_CHECKSUM_LABEL, done, private,
199 ZIO_PRIORITY_SYNC_READ, flags, B_TRUE));
200 }
201
202 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)203 vdev_label_write(zio_t *zio, vdev_t *vd, int l, abd_t *buf, uint64_t offset,
204 uint64_t size, zio_done_func_t *done, void *private, int flags)
205 {
206 ASSERT(
207 spa_config_held(zio->io_spa, SCL_STATE, RW_READER) == SCL_STATE ||
208 spa_config_held(zio->io_spa, SCL_STATE, RW_WRITER) == SCL_STATE);
209 ASSERT(flags & ZIO_FLAG_CONFIG_WRITER);
210
211 zio_nowait(zio_write_phys(zio, vd,
212 vdev_label_offset(vd->vdev_psize, l, offset),
213 size, buf, ZIO_CHECKSUM_LABEL, done, private,
214 ZIO_PRIORITY_SYNC_WRITE, flags, B_TRUE));
215 }
216
217 /*
218 * Generate the nvlist representing this vdev's stats
219 */
220 void
vdev_config_generate_stats(vdev_t * vd,nvlist_t * nv)221 vdev_config_generate_stats(vdev_t *vd, nvlist_t *nv)
222 {
223 nvlist_t *nvx;
224 vdev_stat_t *vs;
225 vdev_stat_ex_t *vsx;
226
227 vs = kmem_alloc(sizeof (*vs), KM_SLEEP);
228 vsx = kmem_alloc(sizeof (*vsx), KM_SLEEP);
229
230 vdev_get_stats_ex(vd, vs, vsx);
231 fnvlist_add_uint64_array(nv, ZPOOL_CONFIG_VDEV_STATS,
232 (uint64_t *)vs, sizeof (*vs) / sizeof (uint64_t));
233
234 /*
235 * Add extended stats into a special extended stats nvlist. This keeps
236 * all the extended stats nicely grouped together. The extended stats
237 * nvlist is then added to the main nvlist.
238 */
239 nvx = fnvlist_alloc();
240
241 /* ZIOs in flight to disk */
242 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_ACTIVE_QUEUE,
243 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_READ]);
244
245 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_ACTIVE_QUEUE,
246 vsx->vsx_active_queue[ZIO_PRIORITY_SYNC_WRITE]);
247
248 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_ACTIVE_QUEUE,
249 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_READ]);
250
251 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_ACTIVE_QUEUE,
252 vsx->vsx_active_queue[ZIO_PRIORITY_ASYNC_WRITE]);
253
254 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_ACTIVE_QUEUE,
255 vsx->vsx_active_queue[ZIO_PRIORITY_SCRUB]);
256
257 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_ACTIVE_QUEUE,
258 vsx->vsx_active_queue[ZIO_PRIORITY_TRIM]);
259
260 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_REBUILD_ACTIVE_QUEUE,
261 vsx->vsx_active_queue[ZIO_PRIORITY_REBUILD]);
262
263 /* ZIOs pending */
264 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_PEND_QUEUE,
265 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_READ]);
266
267 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_PEND_QUEUE,
268 vsx->vsx_pend_queue[ZIO_PRIORITY_SYNC_WRITE]);
269
270 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_PEND_QUEUE,
271 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_READ]);
272
273 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_PEND_QUEUE,
274 vsx->vsx_pend_queue[ZIO_PRIORITY_ASYNC_WRITE]);
275
276 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SCRUB_PEND_QUEUE,
277 vsx->vsx_pend_queue[ZIO_PRIORITY_SCRUB]);
278
279 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_TRIM_PEND_QUEUE,
280 vsx->vsx_pend_queue[ZIO_PRIORITY_TRIM]);
281
282 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_REBUILD_PEND_QUEUE,
283 vsx->vsx_pend_queue[ZIO_PRIORITY_REBUILD]);
284
285 /* Histograms */
286 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_R_LAT_HISTO,
287 vsx->vsx_total_histo[ZIO_TYPE_READ],
288 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_READ]));
289
290 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TOT_W_LAT_HISTO,
291 vsx->vsx_total_histo[ZIO_TYPE_WRITE],
292 ARRAY_SIZE(vsx->vsx_total_histo[ZIO_TYPE_WRITE]));
293
294 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_R_LAT_HISTO,
295 vsx->vsx_disk_histo[ZIO_TYPE_READ],
296 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_READ]));
297
298 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_DISK_W_LAT_HISTO,
299 vsx->vsx_disk_histo[ZIO_TYPE_WRITE],
300 ARRAY_SIZE(vsx->vsx_disk_histo[ZIO_TYPE_WRITE]));
301
302 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_R_LAT_HISTO,
303 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ],
304 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_READ]));
305
306 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_W_LAT_HISTO,
307 vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE],
308 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SYNC_WRITE]));
309
310 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_R_LAT_HISTO,
311 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ],
312 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_READ]));
313
314 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_W_LAT_HISTO,
315 vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE],
316 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_ASYNC_WRITE]));
317
318 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SCRUB_LAT_HISTO,
319 vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB],
320 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_SCRUB]));
321
322 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_TRIM_LAT_HISTO,
323 vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM],
324 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_TRIM]));
325
326 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_REBUILD_LAT_HISTO,
327 vsx->vsx_queue_histo[ZIO_PRIORITY_REBUILD],
328 ARRAY_SIZE(vsx->vsx_queue_histo[ZIO_PRIORITY_REBUILD]));
329
330 /* Request sizes */
331 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_R_HISTO,
332 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ],
333 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_READ]));
334
335 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_IND_W_HISTO,
336 vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE],
337 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SYNC_WRITE]));
338
339 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_R_HISTO,
340 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ],
341 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_READ]));
342
343 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_IND_W_HISTO,
344 vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE],
345 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_ASYNC_WRITE]));
346
347 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_SCRUB_HISTO,
348 vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB],
349 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_SCRUB]));
350
351 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_TRIM_HISTO,
352 vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM],
353 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_TRIM]));
354
355 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_IND_REBUILD_HISTO,
356 vsx->vsx_ind_histo[ZIO_PRIORITY_REBUILD],
357 ARRAY_SIZE(vsx->vsx_ind_histo[ZIO_PRIORITY_REBUILD]));
358
359 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_R_HISTO,
360 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ],
361 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_READ]));
362
363 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_SYNC_AGG_W_HISTO,
364 vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE],
365 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SYNC_WRITE]));
366
367 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_R_HISTO,
368 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ],
369 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_READ]));
370
371 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_ASYNC_AGG_W_HISTO,
372 vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE],
373 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_ASYNC_WRITE]));
374
375 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_SCRUB_HISTO,
376 vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB],
377 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_SCRUB]));
378
379 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_TRIM_HISTO,
380 vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM],
381 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_TRIM]));
382
383 fnvlist_add_uint64_array(nvx, ZPOOL_CONFIG_VDEV_AGG_REBUILD_HISTO,
384 vsx->vsx_agg_histo[ZIO_PRIORITY_REBUILD],
385 ARRAY_SIZE(vsx->vsx_agg_histo[ZIO_PRIORITY_REBUILD]));
386
387 /* IO delays */
388 fnvlist_add_uint64(nvx, ZPOOL_CONFIG_VDEV_SLOW_IOS, vs->vs_slow_ios);
389
390 /* Add extended stats nvlist to main nvlist */
391 fnvlist_add_nvlist(nv, ZPOOL_CONFIG_VDEV_STATS_EX, nvx);
392
393 fnvlist_free(nvx);
394 kmem_free(vs, sizeof (*vs));
395 kmem_free(vsx, sizeof (*vsx));
396 }
397
398 static void
root_vdev_actions_getprogress(vdev_t * vd,nvlist_t * nvl)399 root_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl)
400 {
401 spa_t *spa = vd->vdev_spa;
402
403 if (vd != spa->spa_root_vdev)
404 return;
405
406 /* provide either current or previous scan information */
407 pool_scan_stat_t ps;
408 if (spa_scan_get_stats(spa, &ps) == 0) {
409 fnvlist_add_uint64_array(nvl,
410 ZPOOL_CONFIG_SCAN_STATS, (uint64_t *)&ps,
411 sizeof (pool_scan_stat_t) / sizeof (uint64_t));
412 }
413
414 pool_removal_stat_t prs;
415 if (spa_removal_get_stats(spa, &prs) == 0) {
416 fnvlist_add_uint64_array(nvl,
417 ZPOOL_CONFIG_REMOVAL_STATS, (uint64_t *)&prs,
418 sizeof (prs) / sizeof (uint64_t));
419 }
420
421 pool_checkpoint_stat_t pcs;
422 if (spa_checkpoint_get_stats(spa, &pcs) == 0) {
423 fnvlist_add_uint64_array(nvl,
424 ZPOOL_CONFIG_CHECKPOINT_STATS, (uint64_t *)&pcs,
425 sizeof (pcs) / sizeof (uint64_t));
426 }
427
428 pool_raidz_expand_stat_t pres;
429 if (spa_raidz_expand_get_stats(spa, &pres) == 0) {
430 fnvlist_add_uint64_array(nvl,
431 ZPOOL_CONFIG_RAIDZ_EXPAND_STATS, (uint64_t *)&pres,
432 sizeof (pres) / sizeof (uint64_t));
433 }
434 }
435
436 static void
top_vdev_actions_getprogress(vdev_t * vd,nvlist_t * nvl)437 top_vdev_actions_getprogress(vdev_t *vd, nvlist_t *nvl)
438 {
439 if (vd == vd->vdev_top) {
440 vdev_rebuild_stat_t vrs;
441 if (vdev_rebuild_get_stats(vd, &vrs) == 0) {
442 fnvlist_add_uint64_array(nvl,
443 ZPOOL_CONFIG_REBUILD_STATS, (uint64_t *)&vrs,
444 sizeof (vrs) / sizeof (uint64_t));
445 }
446 }
447 }
448
449 /*
450 * Generate the nvlist representing this vdev's config.
451 */
452 nvlist_t *
vdev_config_generate(spa_t * spa,vdev_t * vd,boolean_t getstats,vdev_config_flag_t flags)453 vdev_config_generate(spa_t *spa, vdev_t *vd, boolean_t getstats,
454 vdev_config_flag_t flags)
455 {
456 nvlist_t *nv = NULL;
457 vdev_indirect_config_t *vic = &vd->vdev_indirect_config;
458
459 nv = fnvlist_alloc();
460
461 fnvlist_add_string(nv, ZPOOL_CONFIG_TYPE, vd->vdev_ops->vdev_op_type);
462 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE)))
463 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ID, vd->vdev_id);
464 fnvlist_add_uint64(nv, ZPOOL_CONFIG_GUID, vd->vdev_guid);
465
466 if (vd->vdev_path != NULL)
467 fnvlist_add_string(nv, ZPOOL_CONFIG_PATH, vd->vdev_path);
468
469 if (vd->vdev_devid != NULL)
470 fnvlist_add_string(nv, ZPOOL_CONFIG_DEVID, vd->vdev_devid);
471
472 if (vd->vdev_physpath != NULL)
473 fnvlist_add_string(nv, ZPOOL_CONFIG_PHYS_PATH,
474 vd->vdev_physpath);
475
476 if (vd->vdev_enc_sysfs_path != NULL)
477 fnvlist_add_string(nv, ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH,
478 vd->vdev_enc_sysfs_path);
479
480 if (vd->vdev_fru != NULL)
481 fnvlist_add_string(nv, ZPOOL_CONFIG_FRU, vd->vdev_fru);
482
483 if (vd->vdev_ops->vdev_op_config_generate != NULL)
484 vd->vdev_ops->vdev_op_config_generate(vd, nv);
485
486 if (vd->vdev_wholedisk != -1ULL) {
487 fnvlist_add_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK,
488 vd->vdev_wholedisk);
489 }
490
491 if (vd->vdev_not_present && !(flags & VDEV_CONFIG_MISSING))
492 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NOT_PRESENT, 1);
493
494 if (vd->vdev_isspare)
495 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_SPARE, 1);
496
497 if (flags & VDEV_CONFIG_L2CACHE)
498 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASHIFT, vd->vdev_ashift);
499
500 if (!(flags & (VDEV_CONFIG_SPARE | VDEV_CONFIG_L2CACHE)) &&
501 vd == vd->vdev_top) {
502 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_ARRAY,
503 vd->vdev_ms_array);
504 fnvlist_add_uint64(nv, ZPOOL_CONFIG_METASLAB_SHIFT,
505 vd->vdev_ms_shift);
506 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASHIFT, vd->vdev_ashift);
507 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ASIZE,
508 vd->vdev_asize);
509 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_LOG, vd->vdev_islog);
510 if (vd->vdev_noalloc) {
511 fnvlist_add_uint64(nv, ZPOOL_CONFIG_NONALLOCATING,
512 vd->vdev_noalloc);
513 }
514
515 /*
516 * Slog devices are removed synchronously so don't
517 * persist the vdev_removing flag to the label.
518 */
519 if (vd->vdev_removing && !vd->vdev_islog) {
520 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVING,
521 vd->vdev_removing);
522 }
523
524 /* zpool command expects alloc class data */
525 if (getstats && vd->vdev_alloc_bias != VDEV_BIAS_NONE) {
526 const char *bias = NULL;
527
528 switch (vd->vdev_alloc_bias) {
529 case VDEV_BIAS_LOG:
530 bias = VDEV_ALLOC_BIAS_LOG;
531 break;
532 case VDEV_BIAS_SPECIAL:
533 bias = VDEV_ALLOC_BIAS_SPECIAL;
534 break;
535 case VDEV_BIAS_DEDUP:
536 bias = VDEV_ALLOC_BIAS_DEDUP;
537 break;
538 default:
539 ASSERT3U(vd->vdev_alloc_bias, ==,
540 VDEV_BIAS_NONE);
541 }
542 fnvlist_add_string(nv, ZPOOL_CONFIG_ALLOCATION_BIAS,
543 bias);
544 }
545 }
546
547 if (vd->vdev_dtl_sm != NULL) {
548 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DTL,
549 space_map_object(vd->vdev_dtl_sm));
550 }
551
552 if (vic->vic_mapping_object != 0) {
553 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_OBJECT,
554 vic->vic_mapping_object);
555 }
556
557 if (vic->vic_births_object != 0) {
558 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_BIRTHS,
559 vic->vic_births_object);
560 }
561
562 if (vic->vic_prev_indirect_vdev != UINT64_MAX) {
563 fnvlist_add_uint64(nv, ZPOOL_CONFIG_PREV_INDIRECT_VDEV,
564 vic->vic_prev_indirect_vdev);
565 }
566
567 if (vd->vdev_crtxg)
568 fnvlist_add_uint64(nv, ZPOOL_CONFIG_CREATE_TXG, vd->vdev_crtxg);
569
570 if (vd->vdev_expansion_time)
571 fnvlist_add_uint64(nv, ZPOOL_CONFIG_EXPANSION_TIME,
572 vd->vdev_expansion_time);
573
574 if (flags & VDEV_CONFIG_MOS) {
575 if (vd->vdev_leaf_zap != 0) {
576 ASSERT(vd->vdev_ops->vdev_op_leaf);
577 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_LEAF_ZAP,
578 vd->vdev_leaf_zap);
579 }
580
581 if (vd->vdev_top_zap != 0) {
582 ASSERT(vd == vd->vdev_top);
583 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_TOP_ZAP,
584 vd->vdev_top_zap);
585 }
586
587 if (vd->vdev_ops == &vdev_root_ops && vd->vdev_root_zap != 0 &&
588 spa_feature_is_active(vd->vdev_spa, SPA_FEATURE_AVZ_V2)) {
589 fnvlist_add_uint64(nv, ZPOOL_CONFIG_VDEV_ROOT_ZAP,
590 vd->vdev_root_zap);
591 }
592
593 if (vd->vdev_resilver_deferred) {
594 ASSERT(vd->vdev_ops->vdev_op_leaf);
595 ASSERT(spa->spa_resilver_deferred);
596 fnvlist_add_boolean(nv, ZPOOL_CONFIG_RESILVER_DEFER);
597 }
598 }
599
600 if (getstats) {
601 vdev_config_generate_stats(vd, nv);
602
603 root_vdev_actions_getprogress(vd, nv);
604 top_vdev_actions_getprogress(vd, nv);
605
606 /*
607 * Note: this can be called from open context
608 * (spa_get_stats()), so we need the rwlock to prevent
609 * the mapping from being changed by condensing.
610 */
611 rw_enter(&vd->vdev_indirect_rwlock, RW_READER);
612 if (vd->vdev_indirect_mapping != NULL) {
613 ASSERT(vd->vdev_indirect_births != NULL);
614 vdev_indirect_mapping_t *vim =
615 vd->vdev_indirect_mapping;
616 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE,
617 vdev_indirect_mapping_size(vim));
618 }
619 rw_exit(&vd->vdev_indirect_rwlock);
620 if (vd->vdev_mg != NULL &&
621 vd->vdev_mg->mg_fragmentation != ZFS_FRAG_INVALID) {
622 /*
623 * Compute approximately how much memory would be used
624 * for the indirect mapping if this device were to
625 * be removed.
626 *
627 * Note: If the frag metric is invalid, then not
628 * enough metaslabs have been converted to have
629 * histograms.
630 */
631 uint64_t seg_count = 0;
632 uint64_t to_alloc = vd->vdev_stat.vs_alloc;
633
634 /*
635 * There are the same number of allocated segments
636 * as free segments, so we will have at least one
637 * entry per free segment. However, small free
638 * segments (smaller than vdev_removal_max_span)
639 * will be combined with adjacent allocated segments
640 * as a single mapping.
641 */
642 for (int i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) {
643 if (i + 1 < highbit64(vdev_removal_max_span)
644 - 1) {
645 to_alloc +=
646 vd->vdev_mg->mg_histogram[i] <<
647 (i + 1);
648 } else {
649 seg_count +=
650 vd->vdev_mg->mg_histogram[i];
651 }
652 }
653
654 /*
655 * The maximum length of a mapping is
656 * zfs_remove_max_segment, so we need at least one entry
657 * per zfs_remove_max_segment of allocated data.
658 */
659 seg_count += to_alloc / spa_remove_max_segment(spa);
660
661 fnvlist_add_uint64(nv, ZPOOL_CONFIG_INDIRECT_SIZE,
662 seg_count *
663 sizeof (vdev_indirect_mapping_entry_phys_t));
664 }
665 }
666
667 if (!vd->vdev_ops->vdev_op_leaf) {
668 nvlist_t **child;
669 uint64_t c;
670
671 ASSERT(!vd->vdev_ishole);
672
673 child = kmem_alloc(vd->vdev_children * sizeof (nvlist_t *),
674 KM_SLEEP);
675
676 for (c = 0; c < vd->vdev_children; c++) {
677 child[c] = vdev_config_generate(spa, vd->vdev_child[c],
678 getstats, flags);
679 }
680
681 fnvlist_add_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
682 (const nvlist_t * const *)child, vd->vdev_children);
683
684 for (c = 0; c < vd->vdev_children; c++)
685 nvlist_free(child[c]);
686
687 kmem_free(child, vd->vdev_children * sizeof (nvlist_t *));
688
689 } else {
690 const char *aux = NULL;
691
692 if (vd->vdev_offline && !vd->vdev_tmpoffline)
693 fnvlist_add_uint64(nv, ZPOOL_CONFIG_OFFLINE, B_TRUE);
694 if (vd->vdev_resilver_txg != 0)
695 fnvlist_add_uint64(nv, ZPOOL_CONFIG_RESILVER_TXG,
696 vd->vdev_resilver_txg);
697 if (vd->vdev_rebuild_txg != 0)
698 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REBUILD_TXG,
699 vd->vdev_rebuild_txg);
700 if (vd->vdev_faulted)
701 fnvlist_add_uint64(nv, ZPOOL_CONFIG_FAULTED, B_TRUE);
702 if (vd->vdev_degraded)
703 fnvlist_add_uint64(nv, ZPOOL_CONFIG_DEGRADED, B_TRUE);
704 if (vd->vdev_removed)
705 fnvlist_add_uint64(nv, ZPOOL_CONFIG_REMOVED, B_TRUE);
706 if (vd->vdev_unspare)
707 fnvlist_add_uint64(nv, ZPOOL_CONFIG_UNSPARE, B_TRUE);
708 if (vd->vdev_ishole)
709 fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_HOLE, B_TRUE);
710
711 /* Set the reason why we're FAULTED/DEGRADED. */
712 switch (vd->vdev_stat.vs_aux) {
713 case VDEV_AUX_ERR_EXCEEDED:
714 aux = "err_exceeded";
715 break;
716
717 case VDEV_AUX_EXTERNAL:
718 aux = "external";
719 break;
720 }
721
722 if (aux != NULL && !vd->vdev_tmpoffline) {
723 fnvlist_add_string(nv, ZPOOL_CONFIG_AUX_STATE, aux);
724 } else {
725 /*
726 * We're healthy - clear any previous AUX_STATE values.
727 */
728 if (nvlist_exists(nv, ZPOOL_CONFIG_AUX_STATE))
729 nvlist_remove_all(nv, ZPOOL_CONFIG_AUX_STATE);
730 }
731
732 if (vd->vdev_splitting && vd->vdev_orig_guid != 0LL) {
733 fnvlist_add_uint64(nv, ZPOOL_CONFIG_ORIG_GUID,
734 vd->vdev_orig_guid);
735 }
736 }
737
738 return (nv);
739 }
740
741 /*
742 * Generate a view of the top-level vdevs. If we currently have holes
743 * in the namespace, then generate an array which contains a list of holey
744 * vdevs. Additionally, add the number of top-level children that currently
745 * exist.
746 */
747 void
vdev_top_config_generate(spa_t * spa,nvlist_t * config)748 vdev_top_config_generate(spa_t *spa, nvlist_t *config)
749 {
750 vdev_t *rvd = spa->spa_root_vdev;
751 uint64_t *array;
752 uint_t c, idx;
753
754 array = kmem_alloc(rvd->vdev_children * sizeof (uint64_t), KM_SLEEP);
755
756 for (c = 0, idx = 0; c < rvd->vdev_children; c++) {
757 vdev_t *tvd = rvd->vdev_child[c];
758
759 if (tvd->vdev_ishole) {
760 array[idx++] = c;
761 }
762 }
763
764 if (idx) {
765 VERIFY(nvlist_add_uint64_array(config, ZPOOL_CONFIG_HOLE_ARRAY,
766 array, idx) == 0);
767 }
768
769 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN,
770 rvd->vdev_children) == 0);
771
772 kmem_free(array, rvd->vdev_children * sizeof (uint64_t));
773 }
774
775 /*
776 * Returns the configuration from the label of the given vdev. For vdevs
777 * which don't have a txg value stored on their label (i.e. spares/cache)
778 * or have not been completely initialized (txg = 0) just return
779 * the configuration from the first valid label we find. Otherwise,
780 * find the most up-to-date label that does not exceed the specified
781 * 'txg' value.
782 */
783 nvlist_t *
vdev_label_read_config(vdev_t * vd,uint64_t txg)784 vdev_label_read_config(vdev_t *vd, uint64_t txg)
785 {
786 spa_t *spa = vd->vdev_spa;
787 nvlist_t *config = NULL;
788 vdev_phys_t *vp[VDEV_LABELS];
789 abd_t *vp_abd[VDEV_LABELS];
790 zio_t *zio[VDEV_LABELS];
791 uint64_t best_txg = 0;
792 uint64_t label_txg = 0;
793 int error = 0;
794 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL |
795 ZIO_FLAG_SPECULATIVE;
796
797 ASSERT(vd->vdev_validate_thread == curthread ||
798 spa_config_held(spa, SCL_STATE_ALL, RW_WRITER) == SCL_STATE_ALL);
799
800 if (!vdev_readable(vd))
801 return (NULL);
802
803 /*
804 * The label for a dRAID distributed spare is not stored on disk.
805 * Instead it is generated when needed which allows us to bypass
806 * the pipeline when reading the config from the label.
807 */
808 if (vd->vdev_ops == &vdev_draid_spare_ops)
809 return (vdev_draid_read_config_spare(vd));
810
811 for (int l = 0; l < VDEV_LABELS; l++) {
812 vp_abd[l] = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE);
813 vp[l] = abd_to_buf(vp_abd[l]);
814 }
815
816 retry:
817 for (int l = 0; l < VDEV_LABELS; l++) {
818 zio[l] = zio_root(spa, NULL, NULL, flags);
819
820 vdev_label_read(zio[l], vd, l, vp_abd[l],
821 offsetof(vdev_label_t, vl_vdev_phys), sizeof (vdev_phys_t),
822 NULL, NULL, flags);
823 }
824 for (int l = 0; l < VDEV_LABELS; l++) {
825 nvlist_t *label = NULL;
826
827 if (zio_wait(zio[l]) == 0 &&
828 nvlist_unpack(vp[l]->vp_nvlist, sizeof (vp[l]->vp_nvlist),
829 &label, 0) == 0) {
830 /*
831 * Auxiliary vdevs won't have txg values in their
832 * labels and newly added vdevs may not have been
833 * completely initialized so just return the
834 * configuration from the first valid label we
835 * encounter.
836 */
837 error = nvlist_lookup_uint64(label,
838 ZPOOL_CONFIG_POOL_TXG, &label_txg);
839 if ((error || label_txg == 0) && !config) {
840 config = label;
841 for (l++; l < VDEV_LABELS; l++)
842 zio_wait(zio[l]);
843 break;
844 } else if (label_txg <= txg && label_txg > best_txg) {
845 best_txg = label_txg;
846 nvlist_free(config);
847 config = fnvlist_dup(label);
848 }
849 }
850
851 if (label != NULL) {
852 nvlist_free(label);
853 label = NULL;
854 }
855 }
856
857 if (config == NULL && !(flags & ZIO_FLAG_TRYHARD)) {
858 flags |= ZIO_FLAG_TRYHARD;
859 goto retry;
860 }
861
862 /*
863 * We found a valid label but it didn't pass txg restrictions.
864 */
865 if (config == NULL && label_txg != 0) {
866 vdev_dbgmsg(vd, "label discarded as txg is too large "
867 "(%llu > %llu)", (u_longlong_t)label_txg,
868 (u_longlong_t)txg);
869 }
870
871 for (int l = 0; l < VDEV_LABELS; l++) {
872 abd_free(vp_abd[l]);
873 }
874
875 return (config);
876 }
877
878 /*
879 * Determine if a device is in use. The 'spare_guid' parameter will be filled
880 * in with the device guid if this spare is active elsewhere on the system.
881 */
882 static boolean_t
vdev_inuse(vdev_t * vd,uint64_t crtxg,vdev_labeltype_t reason,uint64_t * spare_guid,uint64_t * l2cache_guid)883 vdev_inuse(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason,
884 uint64_t *spare_guid, uint64_t *l2cache_guid)
885 {
886 spa_t *spa = vd->vdev_spa;
887 uint64_t state, pool_guid, device_guid, txg, spare_pool;
888 uint64_t vdtxg = 0;
889 nvlist_t *label;
890
891 if (spare_guid)
892 *spare_guid = 0ULL;
893 if (l2cache_guid)
894 *l2cache_guid = 0ULL;
895
896 /*
897 * Read the label, if any, and perform some basic sanity checks.
898 */
899 if ((label = vdev_label_read_config(vd, -1ULL)) == NULL)
900 return (B_FALSE);
901
902 (void) nvlist_lookup_uint64(label, ZPOOL_CONFIG_CREATE_TXG,
903 &vdtxg);
904
905 if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_STATE,
906 &state) != 0 ||
907 nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID,
908 &device_guid) != 0) {
909 nvlist_free(label);
910 return (B_FALSE);
911 }
912
913 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
914 (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID,
915 &pool_guid) != 0 ||
916 nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_TXG,
917 &txg) != 0)) {
918 nvlist_free(label);
919 return (B_FALSE);
920 }
921
922 nvlist_free(label);
923
924 /*
925 * Check to see if this device indeed belongs to the pool it claims to
926 * be a part of. The only way this is allowed is if the device is a hot
927 * spare (which we check for later on).
928 */
929 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
930 !spa_guid_exists(pool_guid, device_guid) &&
931 !spa_spare_exists(device_guid, NULL, NULL) &&
932 !spa_l2cache_exists(device_guid, NULL))
933 return (B_FALSE);
934
935 /*
936 * If the transaction group is zero, then this an initialized (but
937 * unused) label. This is only an error if the create transaction
938 * on-disk is the same as the one we're using now, in which case the
939 * user has attempted to add the same vdev multiple times in the same
940 * transaction.
941 */
942 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
943 txg == 0 && vdtxg == crtxg)
944 return (B_TRUE);
945
946 /*
947 * Check to see if this is a spare device. We do an explicit check for
948 * spa_has_spare() here because it may be on our pending list of spares
949 * to add.
950 */
951 if (spa_spare_exists(device_guid, &spare_pool, NULL) ||
952 spa_has_spare(spa, device_guid)) {
953 if (spare_guid)
954 *spare_guid = device_guid;
955
956 switch (reason) {
957 case VDEV_LABEL_CREATE:
958 return (B_TRUE);
959
960 case VDEV_LABEL_REPLACE:
961 return (!spa_has_spare(spa, device_guid) ||
962 spare_pool != 0ULL);
963
964 case VDEV_LABEL_SPARE:
965 return (spa_has_spare(spa, device_guid));
966 default:
967 break;
968 }
969 }
970
971 /*
972 * Check to see if this is an l2cache device.
973 */
974 if (spa_l2cache_exists(device_guid, NULL) ||
975 spa_has_l2cache(spa, device_guid)) {
976 if (l2cache_guid)
977 *l2cache_guid = device_guid;
978
979 switch (reason) {
980 case VDEV_LABEL_CREATE:
981 return (B_TRUE);
982
983 case VDEV_LABEL_REPLACE:
984 return (!spa_has_l2cache(spa, device_guid));
985
986 case VDEV_LABEL_L2CACHE:
987 return (spa_has_l2cache(spa, device_guid));
988 default:
989 break;
990 }
991 }
992
993 /*
994 * We can't rely on a pool's state if it's been imported
995 * read-only. Instead we look to see if the pools is marked
996 * read-only in the namespace and set the state to active.
997 */
998 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
999 (spa = spa_by_guid(pool_guid, device_guid)) != NULL &&
1000 spa_mode(spa) == SPA_MODE_READ)
1001 state = POOL_STATE_ACTIVE;
1002
1003 /*
1004 * If the device is marked ACTIVE, then this device is in use by another
1005 * pool on the system.
1006 */
1007 return (state == POOL_STATE_ACTIVE);
1008 }
1009
1010 /*
1011 * Initialize a vdev label. We check to make sure each leaf device is not in
1012 * use, and writable. We put down an initial label which we will later
1013 * overwrite with a complete label. Note that it's important to do this
1014 * sequentially, not in parallel, so that we catch cases of multiple use of the
1015 * same leaf vdev in the vdev we're creating -- e.g. mirroring a disk with
1016 * itself.
1017 */
1018 int
vdev_label_init(vdev_t * vd,uint64_t crtxg,vdev_labeltype_t reason)1019 vdev_label_init(vdev_t *vd, uint64_t crtxg, vdev_labeltype_t reason)
1020 {
1021 spa_t *spa = vd->vdev_spa;
1022 nvlist_t *label;
1023 vdev_phys_t *vp;
1024 abd_t *vp_abd;
1025 abd_t *bootenv;
1026 uberblock_t *ub;
1027 abd_t *ub_abd;
1028 zio_t *zio;
1029 char *buf;
1030 size_t buflen;
1031 int error;
1032 uint64_t spare_guid = 0, l2cache_guid = 0;
1033 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL;
1034 boolean_t reason_spare = (reason == VDEV_LABEL_SPARE || (reason ==
1035 VDEV_LABEL_REMOVE && vd->vdev_isspare));
1036 boolean_t reason_l2cache = (reason == VDEV_LABEL_L2CACHE || (reason ==
1037 VDEV_LABEL_REMOVE && vd->vdev_isl2cache));
1038
1039 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1040
1041 for (int c = 0; c < vd->vdev_children; c++)
1042 if ((error = vdev_label_init(vd->vdev_child[c],
1043 crtxg, reason)) != 0)
1044 return (error);
1045
1046 /* Track the creation time for this vdev */
1047 vd->vdev_crtxg = crtxg;
1048
1049 if (!vd->vdev_ops->vdev_op_leaf || !spa_writeable(spa))
1050 return (0);
1051
1052 /*
1053 * Dead vdevs cannot be initialized.
1054 */
1055 if (vdev_is_dead(vd))
1056 return (SET_ERROR(EIO));
1057
1058 /*
1059 * Determine if the vdev is in use.
1060 */
1061 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPLIT &&
1062 vdev_inuse(vd, crtxg, reason, &spare_guid, &l2cache_guid))
1063 return (SET_ERROR(EBUSY));
1064
1065 /*
1066 * If this is a request to add or replace a spare or l2cache device
1067 * that is in use elsewhere on the system, then we must update the
1068 * guid (which was initialized to a random value) to reflect the
1069 * actual GUID (which is shared between multiple pools).
1070 */
1071 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_L2CACHE &&
1072 spare_guid != 0ULL) {
1073 uint64_t guid_delta = spare_guid - vd->vdev_guid;
1074
1075 vd->vdev_guid += guid_delta;
1076
1077 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent)
1078 pvd->vdev_guid_sum += guid_delta;
1079
1080 /*
1081 * If this is a replacement, then we want to fallthrough to the
1082 * rest of the code. If we're adding a spare, then it's already
1083 * labeled appropriately and we can just return.
1084 */
1085 if (reason == VDEV_LABEL_SPARE)
1086 return (0);
1087 ASSERT(reason == VDEV_LABEL_REPLACE ||
1088 reason == VDEV_LABEL_SPLIT);
1089 }
1090
1091 if (reason != VDEV_LABEL_REMOVE && reason != VDEV_LABEL_SPARE &&
1092 l2cache_guid != 0ULL) {
1093 uint64_t guid_delta = l2cache_guid - vd->vdev_guid;
1094
1095 vd->vdev_guid += guid_delta;
1096
1097 for (vdev_t *pvd = vd; pvd != NULL; pvd = pvd->vdev_parent)
1098 pvd->vdev_guid_sum += guid_delta;
1099
1100 /*
1101 * If this is a replacement, then we want to fallthrough to the
1102 * rest of the code. If we're adding an l2cache, then it's
1103 * already labeled appropriately and we can just return.
1104 */
1105 if (reason == VDEV_LABEL_L2CACHE)
1106 return (0);
1107 ASSERT(reason == VDEV_LABEL_REPLACE);
1108 }
1109
1110 /*
1111 * Initialize its label.
1112 */
1113 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE);
1114 abd_zero(vp_abd, sizeof (vdev_phys_t));
1115 vp = abd_to_buf(vp_abd);
1116
1117 /*
1118 * Generate a label describing the pool and our top-level vdev.
1119 * We mark it as being from txg 0 to indicate that it's not
1120 * really part of an active pool just yet. The labels will
1121 * be written again with a meaningful txg by spa_sync().
1122 */
1123 if (reason_spare || reason_l2cache) {
1124 /*
1125 * For inactive hot spares and level 2 ARC devices, we generate
1126 * a special label that identifies as a mutually shared hot
1127 * spare or l2cache device. We write the label in case of
1128 * addition or removal of hot spare or l2cache vdev (in which
1129 * case we want to revert the labels).
1130 */
1131 VERIFY(nvlist_alloc(&label, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1132
1133 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_VERSION,
1134 spa_version(spa)) == 0);
1135 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_POOL_STATE,
1136 reason_spare ? POOL_STATE_SPARE : POOL_STATE_L2CACHE) == 0);
1137 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_GUID,
1138 vd->vdev_guid) == 0);
1139
1140 /*
1141 * This is merely to facilitate reporting the ashift of the
1142 * cache device through zdb. The actual retrieval of the
1143 * ashift (in vdev_alloc()) uses the nvlist
1144 * spa->spa_l2cache->sav_config (populated in
1145 * spa_ld_open_aux_vdevs()).
1146 */
1147 if (reason_l2cache) {
1148 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_ASHIFT,
1149 vd->vdev_ashift) == 0);
1150 }
1151
1152 /*
1153 * Add path information to help find it during pool import
1154 */
1155 if (vd->vdev_path != NULL) {
1156 VERIFY(nvlist_add_string(label, ZPOOL_CONFIG_PATH,
1157 vd->vdev_path) == 0);
1158 }
1159 if (vd->vdev_devid != NULL) {
1160 VERIFY(nvlist_add_string(label, ZPOOL_CONFIG_DEVID,
1161 vd->vdev_devid) == 0);
1162 }
1163 if (vd->vdev_physpath != NULL) {
1164 VERIFY(nvlist_add_string(label, ZPOOL_CONFIG_PHYS_PATH,
1165 vd->vdev_physpath) == 0);
1166 }
1167
1168 /*
1169 * When spare or l2cache (aux) vdev is added during pool
1170 * creation, spa->spa_uberblock is not written until this
1171 * point. Write it on next config sync.
1172 */
1173 if (uberblock_verify(&spa->spa_uberblock))
1174 spa->spa_aux_sync_uber = B_TRUE;
1175 } else {
1176 uint64_t txg = 0ULL;
1177
1178 if (reason == VDEV_LABEL_SPLIT)
1179 txg = spa->spa_uberblock.ub_txg;
1180 label = spa_config_generate(spa, vd, txg, B_FALSE);
1181
1182 /*
1183 * Add our creation time. This allows us to detect multiple
1184 * vdev uses as described above, and automatically expires if we
1185 * fail.
1186 */
1187 VERIFY(nvlist_add_uint64(label, ZPOOL_CONFIG_CREATE_TXG,
1188 crtxg) == 0);
1189 }
1190
1191 buf = vp->vp_nvlist;
1192 buflen = sizeof (vp->vp_nvlist);
1193
1194 error = nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP);
1195 if (error != 0) {
1196 nvlist_free(label);
1197 abd_free(vp_abd);
1198 /* EFAULT means nvlist_pack ran out of room */
1199 return (SET_ERROR(error == EFAULT ? ENAMETOOLONG : EINVAL));
1200 }
1201
1202 /*
1203 * Initialize uberblock template.
1204 */
1205 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_RING, B_TRUE);
1206 abd_copy_from_buf(ub_abd, &spa->spa_uberblock, sizeof (uberblock_t));
1207 abd_zero_off(ub_abd, sizeof (uberblock_t),
1208 VDEV_UBERBLOCK_RING - sizeof (uberblock_t));
1209 ub = abd_to_buf(ub_abd);
1210 ub->ub_txg = 0;
1211
1212 /* Initialize the 2nd padding area. */
1213 bootenv = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE);
1214 abd_zero(bootenv, VDEV_PAD_SIZE);
1215
1216 /*
1217 * Write everything in parallel.
1218 */
1219 retry:
1220 zio = zio_root(spa, NULL, NULL, flags);
1221
1222 for (int l = 0; l < VDEV_LABELS; l++) {
1223
1224 vdev_label_write(zio, vd, l, vp_abd,
1225 offsetof(vdev_label_t, vl_vdev_phys),
1226 sizeof (vdev_phys_t), NULL, NULL, flags);
1227
1228 /*
1229 * Skip the 1st padding area.
1230 * Zero out the 2nd padding area where it might have
1231 * left over data from previous filesystem format.
1232 */
1233 vdev_label_write(zio, vd, l, bootenv,
1234 offsetof(vdev_label_t, vl_be),
1235 VDEV_PAD_SIZE, NULL, NULL, flags);
1236
1237 vdev_label_write(zio, vd, l, ub_abd,
1238 offsetof(vdev_label_t, vl_uberblock),
1239 VDEV_UBERBLOCK_RING, NULL, NULL, flags);
1240 }
1241
1242 error = zio_wait(zio);
1243
1244 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) {
1245 flags |= ZIO_FLAG_TRYHARD;
1246 goto retry;
1247 }
1248
1249 nvlist_free(label);
1250 abd_free(bootenv);
1251 abd_free(ub_abd);
1252 abd_free(vp_abd);
1253
1254 /*
1255 * If this vdev hasn't been previously identified as a spare, then we
1256 * mark it as such only if a) we are labeling it as a spare, or b) it
1257 * exists as a spare elsewhere in the system. Do the same for
1258 * level 2 ARC devices.
1259 */
1260 if (error == 0 && !vd->vdev_isspare &&
1261 (reason == VDEV_LABEL_SPARE ||
1262 spa_spare_exists(vd->vdev_guid, NULL, NULL)))
1263 spa_spare_add(vd);
1264
1265 if (error == 0 && !vd->vdev_isl2cache &&
1266 (reason == VDEV_LABEL_L2CACHE ||
1267 spa_l2cache_exists(vd->vdev_guid, NULL)))
1268 spa_l2cache_add(vd);
1269
1270 return (error);
1271 }
1272
1273 /*
1274 * Done callback for vdev_label_read_bootenv_impl. If this is the first
1275 * callback to finish, store our abd in the callback pointer. Otherwise, we
1276 * just free our abd and return.
1277 */
1278 static void
vdev_label_read_bootenv_done(zio_t * zio)1279 vdev_label_read_bootenv_done(zio_t *zio)
1280 {
1281 zio_t *rio = zio->io_private;
1282 abd_t **cbp = rio->io_private;
1283
1284 ASSERT3U(zio->io_size, ==, VDEV_PAD_SIZE);
1285
1286 if (zio->io_error == 0) {
1287 mutex_enter(&rio->io_lock);
1288 if (*cbp == NULL) {
1289 /* Will free this buffer in vdev_label_read_bootenv. */
1290 *cbp = zio->io_abd;
1291 } else {
1292 abd_free(zio->io_abd);
1293 }
1294 mutex_exit(&rio->io_lock);
1295 } else {
1296 abd_free(zio->io_abd);
1297 }
1298 }
1299
1300 static void
vdev_label_read_bootenv_impl(zio_t * zio,vdev_t * vd,int flags)1301 vdev_label_read_bootenv_impl(zio_t *zio, vdev_t *vd, int flags)
1302 {
1303 for (int c = 0; c < vd->vdev_children; c++)
1304 vdev_label_read_bootenv_impl(zio, vd->vdev_child[c], flags);
1305
1306 /*
1307 * We just use the first label that has a correct checksum; the
1308 * bootloader should have rewritten them all to be the same on boot,
1309 * and any changes we made since boot have been the same across all
1310 * labels.
1311 */
1312 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd)) {
1313 for (int l = 0; l < VDEV_LABELS; l++) {
1314 vdev_label_read(zio, vd, l,
1315 abd_alloc_linear(VDEV_PAD_SIZE, B_FALSE),
1316 offsetof(vdev_label_t, vl_be), VDEV_PAD_SIZE,
1317 vdev_label_read_bootenv_done, zio, flags);
1318 }
1319 }
1320 }
1321
1322 int
vdev_label_read_bootenv(vdev_t * rvd,nvlist_t * bootenv)1323 vdev_label_read_bootenv(vdev_t *rvd, nvlist_t *bootenv)
1324 {
1325 nvlist_t *config;
1326 spa_t *spa = rvd->vdev_spa;
1327 abd_t *abd = NULL;
1328 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL |
1329 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD;
1330
1331 ASSERT(bootenv);
1332 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1333
1334 zio_t *zio = zio_root(spa, NULL, &abd, flags);
1335 vdev_label_read_bootenv_impl(zio, rvd, flags);
1336 int err = zio_wait(zio);
1337
1338 if (abd != NULL) {
1339 char *buf;
1340 vdev_boot_envblock_t *vbe = abd_to_buf(abd);
1341
1342 vbe->vbe_version = ntohll(vbe->vbe_version);
1343 switch (vbe->vbe_version) {
1344 case VB_RAW:
1345 /*
1346 * if we have textual data in vbe_bootenv, create nvlist
1347 * with key "envmap".
1348 */
1349 fnvlist_add_uint64(bootenv, BOOTENV_VERSION, VB_RAW);
1350 vbe->vbe_bootenv[sizeof (vbe->vbe_bootenv) - 1] = '\0';
1351 fnvlist_add_string(bootenv, GRUB_ENVMAP,
1352 vbe->vbe_bootenv);
1353 break;
1354
1355 case VB_NVLIST:
1356 err = nvlist_unpack(vbe->vbe_bootenv,
1357 sizeof (vbe->vbe_bootenv), &config, 0);
1358 if (err == 0) {
1359 fnvlist_merge(bootenv, config);
1360 nvlist_free(config);
1361 break;
1362 }
1363 zfs_fallthrough;
1364 default:
1365 /* Check for FreeBSD zfs bootonce command string */
1366 buf = abd_to_buf(abd);
1367 if (*buf == '\0') {
1368 fnvlist_add_uint64(bootenv, BOOTENV_VERSION,
1369 VB_NVLIST);
1370 break;
1371 }
1372 fnvlist_add_string(bootenv, FREEBSD_BOOTONCE, buf);
1373 }
1374
1375 /*
1376 * abd was allocated in vdev_label_read_bootenv_impl()
1377 */
1378 abd_free(abd);
1379 /*
1380 * If we managed to read any successfully,
1381 * return success.
1382 */
1383 return (0);
1384 }
1385 return (err);
1386 }
1387
1388 int
vdev_label_write_bootenv(vdev_t * vd,nvlist_t * env)1389 vdev_label_write_bootenv(vdev_t *vd, nvlist_t *env)
1390 {
1391 zio_t *zio;
1392 spa_t *spa = vd->vdev_spa;
1393 vdev_boot_envblock_t *bootenv;
1394 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL;
1395 int error;
1396 size_t nvsize;
1397 char *nvbuf;
1398 const char *tmp;
1399
1400 error = nvlist_size(env, &nvsize, NV_ENCODE_XDR);
1401 if (error != 0)
1402 return (SET_ERROR(error));
1403
1404 if (nvsize >= sizeof (bootenv->vbe_bootenv)) {
1405 return (SET_ERROR(E2BIG));
1406 }
1407
1408 ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
1409
1410 error = ENXIO;
1411 for (int c = 0; c < vd->vdev_children; c++) {
1412 int child_err;
1413
1414 child_err = vdev_label_write_bootenv(vd->vdev_child[c], env);
1415 /*
1416 * As long as any of the disks managed to write all of their
1417 * labels successfully, return success.
1418 */
1419 if (child_err == 0)
1420 error = child_err;
1421 }
1422
1423 if (!vd->vdev_ops->vdev_op_leaf || vdev_is_dead(vd) ||
1424 !vdev_writeable(vd)) {
1425 return (error);
1426 }
1427 ASSERT3U(sizeof (*bootenv), ==, VDEV_PAD_SIZE);
1428 abd_t *abd = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE);
1429 abd_zero(abd, VDEV_PAD_SIZE);
1430
1431 bootenv = abd_borrow_buf_copy(abd, VDEV_PAD_SIZE);
1432 nvbuf = bootenv->vbe_bootenv;
1433 nvsize = sizeof (bootenv->vbe_bootenv);
1434
1435 bootenv->vbe_version = fnvlist_lookup_uint64(env, BOOTENV_VERSION);
1436 switch (bootenv->vbe_version) {
1437 case VB_RAW:
1438 if (nvlist_lookup_string(env, GRUB_ENVMAP, &tmp) == 0) {
1439 (void) strlcpy(bootenv->vbe_bootenv, tmp, nvsize);
1440 }
1441 error = 0;
1442 break;
1443
1444 case VB_NVLIST:
1445 error = nvlist_pack(env, &nvbuf, &nvsize, NV_ENCODE_XDR,
1446 KM_SLEEP);
1447 break;
1448
1449 default:
1450 error = EINVAL;
1451 break;
1452 }
1453
1454 if (error == 0) {
1455 bootenv->vbe_version = htonll(bootenv->vbe_version);
1456 abd_return_buf_copy(abd, bootenv, VDEV_PAD_SIZE);
1457 } else {
1458 abd_free(abd);
1459 return (SET_ERROR(error));
1460 }
1461
1462 retry:
1463 zio = zio_root(spa, NULL, NULL, flags);
1464 for (int l = 0; l < VDEV_LABELS; l++) {
1465 vdev_label_write(zio, vd, l, abd,
1466 offsetof(vdev_label_t, vl_be),
1467 VDEV_PAD_SIZE, NULL, NULL, flags);
1468 }
1469
1470 error = zio_wait(zio);
1471 if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) {
1472 flags |= ZIO_FLAG_TRYHARD;
1473 goto retry;
1474 }
1475
1476 abd_free(abd);
1477 return (error);
1478 }
1479
1480 /*
1481 * ==========================================================================
1482 * uberblock load/sync
1483 * ==========================================================================
1484 */
1485
1486 /*
1487 * Consider the following situation: txg is safely synced to disk. We've
1488 * written the first uberblock for txg + 1, and then we lose power. When we
1489 * come back up, we fail to see the uberblock for txg + 1 because, say,
1490 * it was on a mirrored device and the replica to which we wrote txg + 1
1491 * is now offline. If we then make some changes and sync txg + 1, and then
1492 * the missing replica comes back, then for a few seconds we'll have two
1493 * conflicting uberblocks on disk with the same txg. The solution is simple:
1494 * among uberblocks with equal txg, choose the one with the latest timestamp.
1495 */
1496 static int
vdev_uberblock_compare(const uberblock_t * ub1,const uberblock_t * ub2)1497 vdev_uberblock_compare(const uberblock_t *ub1, const uberblock_t *ub2)
1498 {
1499 int cmp = TREE_CMP(ub1->ub_txg, ub2->ub_txg);
1500
1501 if (likely(cmp))
1502 return (cmp);
1503
1504 cmp = TREE_CMP(ub1->ub_timestamp, ub2->ub_timestamp);
1505 if (likely(cmp))
1506 return (cmp);
1507
1508 /*
1509 * If MMP_VALID(ub) && MMP_SEQ_VALID(ub) then the host has an MMP-aware
1510 * ZFS, e.g. OpenZFS >= 0.7.
1511 *
1512 * If one ub has MMP and the other does not, they were written by
1513 * different hosts, which matters for MMP. So we treat no MMP/no SEQ as
1514 * a 0 value.
1515 *
1516 * Since timestamp and txg are the same if we get this far, either is
1517 * acceptable for importing the pool.
1518 */
1519 unsigned int seq1 = 0;
1520 unsigned int seq2 = 0;
1521
1522 if (MMP_VALID(ub1) && MMP_SEQ_VALID(ub1))
1523 seq1 = MMP_SEQ(ub1);
1524
1525 if (MMP_VALID(ub2) && MMP_SEQ_VALID(ub2))
1526 seq2 = MMP_SEQ(ub2);
1527
1528 return (TREE_CMP(seq1, seq2));
1529 }
1530
1531 struct ubl_cbdata {
1532 uberblock_t ubl_latest; /* Most recent uberblock */
1533 uberblock_t *ubl_ubbest; /* Best uberblock (w/r/t max_txg) */
1534 vdev_t *ubl_vd; /* vdev associated with the above */
1535 };
1536
1537 static void
vdev_uberblock_load_done(zio_t * zio)1538 vdev_uberblock_load_done(zio_t *zio)
1539 {
1540 vdev_t *vd = zio->io_vd;
1541 spa_t *spa = zio->io_spa;
1542 zio_t *rio = zio->io_private;
1543 uberblock_t *ub = abd_to_buf(zio->io_abd);
1544 struct ubl_cbdata *cbp = rio->io_private;
1545
1546 ASSERT3U(zio->io_size, ==, VDEV_UBERBLOCK_SIZE(vd));
1547
1548 if (zio->io_error == 0 && uberblock_verify(ub) == 0) {
1549 mutex_enter(&rio->io_lock);
1550 if (vdev_uberblock_compare(ub, &cbp->ubl_latest) > 0) {
1551 cbp->ubl_latest = *ub;
1552 }
1553 if (ub->ub_txg <= spa->spa_load_max_txg &&
1554 vdev_uberblock_compare(ub, cbp->ubl_ubbest) > 0) {
1555 /*
1556 * Keep track of the vdev in which this uberblock
1557 * was found. We will use this information later
1558 * to obtain the config nvlist associated with
1559 * this uberblock.
1560 */
1561 *cbp->ubl_ubbest = *ub;
1562 cbp->ubl_vd = vd;
1563 }
1564 mutex_exit(&rio->io_lock);
1565 }
1566
1567 abd_free(zio->io_abd);
1568 }
1569
1570 static void
vdev_uberblock_load_impl(zio_t * zio,vdev_t * vd,int flags,struct ubl_cbdata * cbp)1571 vdev_uberblock_load_impl(zio_t *zio, vdev_t *vd, int flags,
1572 struct ubl_cbdata *cbp)
1573 {
1574 for (int c = 0; c < vd->vdev_children; c++)
1575 vdev_uberblock_load_impl(zio, vd->vdev_child[c], flags, cbp);
1576
1577 if (vd->vdev_ops->vdev_op_leaf && vdev_readable(vd) &&
1578 vd->vdev_ops != &vdev_draid_spare_ops) {
1579 for (int l = 0; l < VDEV_LABELS; l++) {
1580 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) {
1581 vdev_label_read(zio, vd, l,
1582 abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd),
1583 B_TRUE), VDEV_UBERBLOCK_OFFSET(vd, n),
1584 VDEV_UBERBLOCK_SIZE(vd),
1585 vdev_uberblock_load_done, zio, flags);
1586 }
1587 }
1588 }
1589 }
1590
1591 /*
1592 * Reads the 'best' uberblock from disk along with its associated
1593 * configuration. First, we read the uberblock array of each label of each
1594 * vdev, keeping track of the uberblock with the highest txg in each array.
1595 * Then, we read the configuration from the same vdev as the best uberblock.
1596 */
1597 void
vdev_uberblock_load(vdev_t * rvd,uberblock_t * ub,nvlist_t ** config)1598 vdev_uberblock_load(vdev_t *rvd, uberblock_t *ub, nvlist_t **config)
1599 {
1600 zio_t *zio;
1601 spa_t *spa = rvd->vdev_spa;
1602 struct ubl_cbdata cb;
1603 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL |
1604 ZIO_FLAG_SPECULATIVE | ZIO_FLAG_TRYHARD;
1605
1606 ASSERT(ub);
1607 ASSERT(config);
1608
1609 memset(ub, 0, sizeof (uberblock_t));
1610 memset(&cb, 0, sizeof (cb));
1611 *config = NULL;
1612
1613 cb.ubl_ubbest = ub;
1614
1615 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
1616 zio = zio_root(spa, NULL, &cb, flags);
1617 vdev_uberblock_load_impl(zio, rvd, flags, &cb);
1618 (void) zio_wait(zio);
1619
1620 /*
1621 * It's possible that the best uberblock was discovered on a label
1622 * that has a configuration which was written in a future txg.
1623 * Search all labels on this vdev to find the configuration that
1624 * matches the txg for our uberblock.
1625 */
1626 if (cb.ubl_vd != NULL) {
1627 vdev_dbgmsg(cb.ubl_vd, "best uberblock found for spa %s. "
1628 "txg %llu", spa->spa_name, (u_longlong_t)ub->ub_txg);
1629
1630 if (ub->ub_raidz_reflow_info !=
1631 cb.ubl_latest.ub_raidz_reflow_info) {
1632 vdev_dbgmsg(cb.ubl_vd,
1633 "spa=%s best uberblock (txg=%llu info=0x%llx) "
1634 "has different raidz_reflow_info than latest "
1635 "uberblock (txg=%llu info=0x%llx)",
1636 spa->spa_name,
1637 (u_longlong_t)ub->ub_txg,
1638 (u_longlong_t)ub->ub_raidz_reflow_info,
1639 (u_longlong_t)cb.ubl_latest.ub_txg,
1640 (u_longlong_t)cb.ubl_latest.ub_raidz_reflow_info);
1641 memset(ub, 0, sizeof (uberblock_t));
1642 spa_config_exit(spa, SCL_ALL, FTAG);
1643 return;
1644 }
1645
1646 *config = vdev_label_read_config(cb.ubl_vd, ub->ub_txg);
1647 if (*config == NULL && spa->spa_extreme_rewind) {
1648 vdev_dbgmsg(cb.ubl_vd, "failed to read label config. "
1649 "Trying again without txg restrictions.");
1650 *config = vdev_label_read_config(cb.ubl_vd, UINT64_MAX);
1651 }
1652 if (*config == NULL) {
1653 vdev_dbgmsg(cb.ubl_vd, "failed to read label config");
1654 }
1655 }
1656 spa_config_exit(spa, SCL_ALL, FTAG);
1657 }
1658
1659 /*
1660 * For use when a leaf vdev is expanded.
1661 * The location of labels 2 and 3 changed, and at the new location the
1662 * uberblock rings are either empty or contain garbage. The sync will write
1663 * new configs there because the vdev is dirty, but expansion also needs the
1664 * uberblock rings copied. Read them from label 0 which did not move.
1665 *
1666 * Since the point is to populate labels {2,3} with valid uberblocks,
1667 * we zero uberblocks we fail to read or which are not valid.
1668 */
1669
1670 static void
vdev_copy_uberblocks(vdev_t * vd)1671 vdev_copy_uberblocks(vdev_t *vd)
1672 {
1673 abd_t *ub_abd;
1674 zio_t *write_zio;
1675 int locks = (SCL_L2ARC | SCL_ZIO);
1676 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL |
1677 ZIO_FLAG_SPECULATIVE;
1678
1679 ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_READER) ==
1680 SCL_STATE);
1681 ASSERT(vd->vdev_ops->vdev_op_leaf);
1682
1683 /*
1684 * No uberblocks are stored on distributed spares, they may be
1685 * safely skipped when expanding a leaf vdev.
1686 */
1687 if (vd->vdev_ops == &vdev_draid_spare_ops)
1688 return;
1689
1690 spa_config_enter(vd->vdev_spa, locks, FTAG, RW_READER);
1691
1692 ub_abd = abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd), B_TRUE);
1693
1694 write_zio = zio_root(vd->vdev_spa, NULL, NULL, flags);
1695 for (int n = 0; n < VDEV_UBERBLOCK_COUNT(vd); n++) {
1696 const int src_label = 0;
1697 zio_t *zio;
1698
1699 zio = zio_root(vd->vdev_spa, NULL, NULL, flags);
1700 vdev_label_read(zio, vd, src_label, ub_abd,
1701 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd),
1702 NULL, NULL, flags);
1703
1704 if (zio_wait(zio) || uberblock_verify(abd_to_buf(ub_abd)))
1705 abd_zero(ub_abd, VDEV_UBERBLOCK_SIZE(vd));
1706
1707 for (int l = 2; l < VDEV_LABELS; l++)
1708 vdev_label_write(write_zio, vd, l, ub_abd,
1709 VDEV_UBERBLOCK_OFFSET(vd, n),
1710 VDEV_UBERBLOCK_SIZE(vd), NULL, NULL,
1711 flags | ZIO_FLAG_DONT_PROPAGATE);
1712 }
1713 (void) zio_wait(write_zio);
1714
1715 spa_config_exit(vd->vdev_spa, locks, FTAG);
1716
1717 abd_free(ub_abd);
1718 }
1719
1720 /*
1721 * On success, increment root zio's count of good writes.
1722 * We only get credit for writes to known-visible vdevs; see spa_vdev_add().
1723 */
1724 static void
vdev_uberblock_sync_done(zio_t * zio)1725 vdev_uberblock_sync_done(zio_t *zio)
1726 {
1727 uint64_t *good_writes = zio->io_private;
1728
1729 if (zio->io_error == 0 && zio->io_vd->vdev_top->vdev_ms_array != 0)
1730 atomic_inc_64(good_writes);
1731 }
1732
1733 /*
1734 * Write the uberblock to all labels of all leaves of the specified vdev.
1735 */
1736 static void
vdev_uberblock_sync(zio_t * zio,uint64_t * good_writes,uberblock_t * ub,vdev_t * vd,int flags)1737 vdev_uberblock_sync(zio_t *zio, uint64_t *good_writes,
1738 uberblock_t *ub, vdev_t *vd, int flags)
1739 {
1740 for (uint64_t c = 0; c < vd->vdev_children; c++) {
1741 vdev_uberblock_sync(zio, good_writes,
1742 ub, vd->vdev_child[c], flags);
1743 }
1744
1745 if (!vd->vdev_ops->vdev_op_leaf)
1746 return;
1747
1748 if (!vdev_writeable(vd))
1749 return;
1750
1751 /*
1752 * There's no need to write uberblocks to a distributed spare, they
1753 * are already stored on all the leaves of the parent dRAID. For
1754 * this same reason vdev_uberblock_load_impl() skips distributed
1755 * spares when reading uberblocks.
1756 */
1757 if (vd->vdev_ops == &vdev_draid_spare_ops)
1758 return;
1759
1760 /* If the vdev was expanded, need to copy uberblock rings. */
1761 if (vd->vdev_state == VDEV_STATE_HEALTHY &&
1762 vd->vdev_copy_uberblocks == B_TRUE) {
1763 vdev_copy_uberblocks(vd);
1764 vd->vdev_copy_uberblocks = B_FALSE;
1765 }
1766
1767 /*
1768 * We chose a slot based on the txg. If this uberblock has a special
1769 * RAIDZ expansion state, then it is essentially an update of the
1770 * current uberblock (it has the same txg). However, the current
1771 * state is committed, so we want to write it to a different slot. If
1772 * we overwrote the same slot, and we lose power during the uberblock
1773 * write, and the disk does not do single-sector overwrites
1774 * atomically (even though it is required to - i.e. we should see
1775 * either the old or the new uberblock), then we could lose this
1776 * txg's uberblock. Rewinding to the previous txg's uberblock may not
1777 * be possible because RAIDZ expansion may have already overwritten
1778 * some of the data, so we need the progress indicator in the
1779 * uberblock.
1780 */
1781 int m = spa_multihost(vd->vdev_spa) ? MMP_BLOCKS_PER_LABEL : 0;
1782 int n = (ub->ub_txg - (RRSS_GET_STATE(ub) == RRSS_SCRATCH_VALID)) %
1783 (VDEV_UBERBLOCK_COUNT(vd) - m);
1784
1785 /* Copy the uberblock_t into the ABD */
1786 abd_t *ub_abd = abd_alloc_for_io(VDEV_UBERBLOCK_SIZE(vd), B_TRUE);
1787 abd_copy_from_buf(ub_abd, ub, sizeof (uberblock_t));
1788 abd_zero_off(ub_abd, sizeof (uberblock_t),
1789 VDEV_UBERBLOCK_SIZE(vd) - sizeof (uberblock_t));
1790
1791 for (int l = 0; l < VDEV_LABELS; l++)
1792 vdev_label_write(zio, vd, l, ub_abd,
1793 VDEV_UBERBLOCK_OFFSET(vd, n), VDEV_UBERBLOCK_SIZE(vd),
1794 vdev_uberblock_sync_done, good_writes,
1795 flags | ZIO_FLAG_DONT_PROPAGATE);
1796
1797 abd_free(ub_abd);
1798 }
1799
1800 /* Sync the uberblocks to all vdevs in svd[] */
1801 int
vdev_uberblock_sync_list(vdev_t ** svd,int svdcount,uberblock_t * ub,int flags)1802 vdev_uberblock_sync_list(vdev_t **svd, int svdcount, uberblock_t *ub, int flags)
1803 {
1804 spa_t *spa = svd[0]->vdev_spa;
1805 zio_t *zio;
1806 uint64_t good_writes = 0;
1807
1808 zio = zio_root(spa, NULL, NULL, flags);
1809
1810 for (int v = 0; v < svdcount; v++)
1811 vdev_uberblock_sync(zio, &good_writes, ub, svd[v], flags);
1812
1813 if (spa->spa_aux_sync_uber) {
1814 for (int v = 0; v < spa->spa_spares.sav_count; v++) {
1815 vdev_uberblock_sync(zio, &good_writes, ub,
1816 spa->spa_spares.sav_vdevs[v], flags);
1817 }
1818 for (int v = 0; v < spa->spa_l2cache.sav_count; v++) {
1819 vdev_uberblock_sync(zio, &good_writes, ub,
1820 spa->spa_l2cache.sav_vdevs[v], flags);
1821 }
1822 }
1823 (void) zio_wait(zio);
1824
1825 /*
1826 * Flush the uberblocks to disk. This ensures that the odd labels
1827 * are no longer needed (because the new uberblocks and the even
1828 * labels are safely on disk), so it is safe to overwrite them.
1829 */
1830 zio = zio_root(spa, NULL, NULL, flags);
1831
1832 for (int v = 0; v < svdcount; v++) {
1833 if (vdev_writeable(svd[v])) {
1834 zio_flush(zio, svd[v]);
1835 }
1836 }
1837 if (spa->spa_aux_sync_uber) {
1838 spa->spa_aux_sync_uber = B_FALSE;
1839 for (int v = 0; v < spa->spa_spares.sav_count; v++) {
1840 if (vdev_writeable(spa->spa_spares.sav_vdevs[v])) {
1841 zio_flush(zio, spa->spa_spares.sav_vdevs[v]);
1842 }
1843 }
1844 for (int v = 0; v < spa->spa_l2cache.sav_count; v++) {
1845 if (vdev_writeable(spa->spa_l2cache.sav_vdevs[v])) {
1846 zio_flush(zio, spa->spa_l2cache.sav_vdevs[v]);
1847 }
1848 }
1849 }
1850
1851 (void) zio_wait(zio);
1852
1853 return (good_writes >= 1 ? 0 : EIO);
1854 }
1855
1856 /*
1857 * On success, increment the count of good writes for our top-level vdev.
1858 */
1859 static void
vdev_label_sync_done(zio_t * zio)1860 vdev_label_sync_done(zio_t *zio)
1861 {
1862 uint64_t *good_writes = zio->io_private;
1863
1864 if (zio->io_error == 0)
1865 atomic_inc_64(good_writes);
1866 }
1867
1868 /*
1869 * If there weren't enough good writes, indicate failure to the parent.
1870 */
1871 static void
vdev_label_sync_top_done(zio_t * zio)1872 vdev_label_sync_top_done(zio_t *zio)
1873 {
1874 uint64_t *good_writes = zio->io_private;
1875
1876 if (*good_writes == 0)
1877 zio->io_error = SET_ERROR(EIO);
1878
1879 kmem_free(good_writes, sizeof (uint64_t));
1880 }
1881
1882 /*
1883 * We ignore errors for log and cache devices, simply free the private data.
1884 */
1885 static void
vdev_label_sync_ignore_done(zio_t * zio)1886 vdev_label_sync_ignore_done(zio_t *zio)
1887 {
1888 kmem_free(zio->io_private, sizeof (uint64_t));
1889 }
1890
1891 /*
1892 * Write all even or odd labels to all leaves of the specified vdev.
1893 */
1894 static void
vdev_label_sync(zio_t * zio,uint64_t * good_writes,vdev_t * vd,int l,uint64_t txg,int flags)1895 vdev_label_sync(zio_t *zio, uint64_t *good_writes,
1896 vdev_t *vd, int l, uint64_t txg, int flags)
1897 {
1898 nvlist_t *label;
1899 vdev_phys_t *vp;
1900 abd_t *vp_abd;
1901 char *buf;
1902 size_t buflen;
1903
1904 for (int c = 0; c < vd->vdev_children; c++) {
1905 vdev_label_sync(zio, good_writes,
1906 vd->vdev_child[c], l, txg, flags);
1907 }
1908
1909 if (!vd->vdev_ops->vdev_op_leaf)
1910 return;
1911
1912 if (!vdev_writeable(vd))
1913 return;
1914
1915 /*
1916 * The top-level config never needs to be written to a distributed
1917 * spare. When read vdev_dspare_label_read_config() will generate
1918 * the config for the vdev_label_read_config().
1919 */
1920 if (vd->vdev_ops == &vdev_draid_spare_ops)
1921 return;
1922
1923 /*
1924 * Generate a label describing the top-level config to which we belong.
1925 */
1926 label = spa_config_generate(vd->vdev_spa, vd, txg, B_FALSE);
1927
1928 vp_abd = abd_alloc_linear(sizeof (vdev_phys_t), B_TRUE);
1929 abd_zero(vp_abd, sizeof (vdev_phys_t));
1930 vp = abd_to_buf(vp_abd);
1931
1932 buf = vp->vp_nvlist;
1933 buflen = sizeof (vp->vp_nvlist);
1934
1935 if (!nvlist_pack(label, &buf, &buflen, NV_ENCODE_XDR, KM_SLEEP)) {
1936 for (; l < VDEV_LABELS; l += 2) {
1937 vdev_label_write(zio, vd, l, vp_abd,
1938 offsetof(vdev_label_t, vl_vdev_phys),
1939 sizeof (vdev_phys_t),
1940 vdev_label_sync_done, good_writes,
1941 flags | ZIO_FLAG_DONT_PROPAGATE);
1942 }
1943 }
1944
1945 abd_free(vp_abd);
1946 nvlist_free(label);
1947 }
1948
1949 static int
vdev_label_sync_list(spa_t * spa,int l,uint64_t txg,int flags)1950 vdev_label_sync_list(spa_t *spa, int l, uint64_t txg, int flags)
1951 {
1952 list_t *dl = &spa->spa_config_dirty_list;
1953 vdev_t *vd;
1954 zio_t *zio;
1955 int error;
1956
1957 /*
1958 * Write the new labels to disk.
1959 */
1960 zio = zio_root(spa, NULL, NULL, flags);
1961
1962 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd)) {
1963 uint64_t *good_writes;
1964
1965 ASSERT(!vd->vdev_ishole);
1966
1967 good_writes = kmem_zalloc(sizeof (uint64_t), KM_SLEEP);
1968 zio_t *vio = zio_null(zio, spa, NULL,
1969 (vd->vdev_islog || vd->vdev_aux != NULL) ?
1970 vdev_label_sync_ignore_done : vdev_label_sync_top_done,
1971 good_writes, flags);
1972 vdev_label_sync(vio, good_writes, vd, l, txg, flags);
1973 zio_nowait(vio);
1974 }
1975
1976 error = zio_wait(zio);
1977
1978 /*
1979 * Flush the new labels to disk.
1980 */
1981 zio = zio_root(spa, NULL, NULL, flags);
1982
1983 for (vd = list_head(dl); vd != NULL; vd = list_next(dl, vd))
1984 zio_flush(zio, vd);
1985
1986 (void) zio_wait(zio);
1987
1988 return (error);
1989 }
1990
1991 /*
1992 * Sync the uberblock and any changes to the vdev configuration.
1993 *
1994 * The order of operations is carefully crafted to ensure that
1995 * if the system panics or loses power at any time, the state on disk
1996 * is still transactionally consistent. The in-line comments below
1997 * describe the failure semantics at each stage.
1998 *
1999 * Moreover, vdev_config_sync() is designed to be idempotent: if it fails
2000 * at any time, you can just call it again, and it will resume its work.
2001 */
2002 int
vdev_config_sync(vdev_t ** svd,int svdcount,uint64_t txg)2003 vdev_config_sync(vdev_t **svd, int svdcount, uint64_t txg)
2004 {
2005 spa_t *spa = svd[0]->vdev_spa;
2006 uberblock_t *ub = &spa->spa_uberblock;
2007 int error = 0;
2008 int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL;
2009
2010 ASSERT(svdcount != 0);
2011 retry:
2012 /*
2013 * Normally, we don't want to try too hard to write every label and
2014 * uberblock. If there is a flaky disk, we don't want the rest of the
2015 * sync process to block while we retry. But if we can't write a
2016 * single label out, we should retry with ZIO_FLAG_TRYHARD before
2017 * bailing out and declaring the pool faulted.
2018 */
2019 if (error != 0) {
2020 if ((flags & ZIO_FLAG_TRYHARD) != 0)
2021 return (error);
2022 flags |= ZIO_FLAG_TRYHARD;
2023 }
2024
2025 ASSERT(ub->ub_txg <= txg);
2026
2027 /*
2028 * If this isn't a resync due to I/O errors,
2029 * and nothing changed in this transaction group,
2030 * and multihost protection isn't enabled,
2031 * and the vdev configuration hasn't changed,
2032 * then there's nothing to do.
2033 */
2034 if (ub->ub_txg < txg) {
2035 boolean_t changed = uberblock_update(ub, spa->spa_root_vdev,
2036 txg, spa->spa_mmp.mmp_delay);
2037
2038 if (!changed && list_is_empty(&spa->spa_config_dirty_list) &&
2039 !spa_multihost(spa))
2040 return (0);
2041 }
2042
2043 if (txg > spa_freeze_txg(spa))
2044 return (0);
2045
2046 ASSERT(txg <= spa->spa_final_txg);
2047
2048 /*
2049 * Flush the write cache of every disk that's been written to
2050 * in this transaction group. This ensures that all blocks
2051 * written in this txg will be committed to stable storage
2052 * before any uberblock that references them.
2053 */
2054 zio_t *zio = zio_root(spa, NULL, NULL, flags);
2055
2056 for (vdev_t *vd =
2057 txg_list_head(&spa->spa_vdev_txg_list, TXG_CLEAN(txg)); vd != NULL;
2058 vd = txg_list_next(&spa->spa_vdev_txg_list, vd, TXG_CLEAN(txg)))
2059 zio_flush(zio, vd);
2060
2061 (void) zio_wait(zio);
2062
2063 /*
2064 * Sync out the even labels (L0, L2) for every dirty vdev. If the
2065 * system dies in the middle of this process, that's OK: all of the
2066 * even labels that made it to disk will be newer than any uberblock,
2067 * and will therefore be considered invalid. The odd labels (L1, L3),
2068 * which have not yet been touched, will still be valid. We flush
2069 * the new labels to disk to ensure that all even-label updates
2070 * are committed to stable storage before the uberblock update.
2071 */
2072 if ((error = vdev_label_sync_list(spa, 0, txg, flags)) != 0) {
2073 if ((flags & ZIO_FLAG_TRYHARD) != 0) {
2074 zfs_dbgmsg("vdev_label_sync_list() returned error %d "
2075 "for pool '%s' when syncing out the even labels "
2076 "of dirty vdevs", error, spa_name(spa));
2077 }
2078 goto retry;
2079 }
2080
2081 /*
2082 * Sync the uberblocks to all vdevs in svd[].
2083 * If the system dies in the middle of this step, there are two cases
2084 * to consider, and the on-disk state is consistent either way:
2085 *
2086 * (1) If none of the new uberblocks made it to disk, then the
2087 * previous uberblock will be the newest, and the odd labels
2088 * (which had not yet been touched) will be valid with respect
2089 * to that uberblock.
2090 *
2091 * (2) If one or more new uberblocks made it to disk, then they
2092 * will be the newest, and the even labels (which had all
2093 * been successfully committed) will be valid with respect
2094 * to the new uberblocks.
2095 */
2096 if ((error = vdev_uberblock_sync_list(svd, svdcount, ub, flags)) != 0) {
2097 if ((flags & ZIO_FLAG_TRYHARD) != 0) {
2098 zfs_dbgmsg("vdev_uberblock_sync_list() returned error "
2099 "%d for pool '%s'", error, spa_name(spa));
2100 }
2101 goto retry;
2102 }
2103
2104 if (spa_multihost(spa))
2105 mmp_update_uberblock(spa, ub);
2106
2107 /*
2108 * Sync out odd labels for every dirty vdev. If the system dies
2109 * in the middle of this process, the even labels and the new
2110 * uberblocks will suffice to open the pool. The next time
2111 * the pool is opened, the first thing we'll do -- before any
2112 * user data is modified -- is mark every vdev dirty so that
2113 * all labels will be brought up to date. We flush the new labels
2114 * to disk to ensure that all odd-label updates are committed to
2115 * stable storage before the next transaction group begins.
2116 */
2117 if ((error = vdev_label_sync_list(spa, 1, txg, flags)) != 0) {
2118 if ((flags & ZIO_FLAG_TRYHARD) != 0) {
2119 zfs_dbgmsg("vdev_label_sync_list() returned error %d "
2120 "for pool '%s' when syncing out the odd labels of "
2121 "dirty vdevs", error, spa_name(spa));
2122 }
2123 goto retry;
2124 }
2125
2126 return (0);
2127 }
2128