xref: /titanic_52/usr/src/uts/common/fs/zfs/vdev.c (revision 380789fc80376bd1573770361cb177a08c7e3524)
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 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/zfs_context.h>
30 #include <sys/fm/fs/zfs.h>
31 #include <sys/spa.h>
32 #include <sys/spa_impl.h>
33 #include <sys/dmu.h>
34 #include <sys/dmu_tx.h>
35 #include <sys/vdev_impl.h>
36 #include <sys/uberblock_impl.h>
37 #include <sys/metaslab.h>
38 #include <sys/metaslab_impl.h>
39 #include <sys/space_map.h>
40 #include <sys/zio.h>
41 #include <sys/zap.h>
42 #include <sys/fs/zfs.h>
43 
44 /*
45  * Virtual device management.
46  */
47 
48 static vdev_ops_t *vdev_ops_table[] = {
49 	&vdev_root_ops,
50 	&vdev_raidz_ops,
51 	&vdev_mirror_ops,
52 	&vdev_replacing_ops,
53 	&vdev_spare_ops,
54 	&vdev_disk_ops,
55 	&vdev_file_ops,
56 	&vdev_missing_ops,
57 	NULL
58 };
59 
60 /* maximum scrub/resilver I/O queue */
61 int zfs_scrub_limit = 70;
62 
63 /*
64  * Given a vdev type, return the appropriate ops vector.
65  */
66 static vdev_ops_t *
67 vdev_getops(const char *type)
68 {
69 	vdev_ops_t *ops, **opspp;
70 
71 	for (opspp = vdev_ops_table; (ops = *opspp) != NULL; opspp++)
72 		if (strcmp(ops->vdev_op_type, type) == 0)
73 			break;
74 
75 	return (ops);
76 }
77 
78 /*
79  * Default asize function: return the MAX of psize with the asize of
80  * all children.  This is what's used by anything other than RAID-Z.
81  */
82 uint64_t
83 vdev_default_asize(vdev_t *vd, uint64_t psize)
84 {
85 	uint64_t asize = P2ROUNDUP(psize, 1ULL << vd->vdev_top->vdev_ashift);
86 	uint64_t csize;
87 	uint64_t c;
88 
89 	for (c = 0; c < vd->vdev_children; c++) {
90 		csize = vdev_psize_to_asize(vd->vdev_child[c], psize);
91 		asize = MAX(asize, csize);
92 	}
93 
94 	return (asize);
95 }
96 
97 /*
98  * Get the replaceable or attachable device size.
99  * If the parent is a mirror or raidz, the replaceable size is the minimum
100  * psize of all its children. For the rest, just return our own psize.
101  *
102  * e.g.
103  *			psize	rsize
104  * root			-	-
105  *	mirror/raidz	-	-
106  *	    disk1	20g	20g
107  *	    disk2 	40g	20g
108  *	disk3 		80g	80g
109  */
110 uint64_t
111 vdev_get_rsize(vdev_t *vd)
112 {
113 	vdev_t *pvd, *cvd;
114 	uint64_t c, rsize;
115 
116 	pvd = vd->vdev_parent;
117 
118 	/*
119 	 * If our parent is NULL or the root, just return our own psize.
120 	 */
121 	if (pvd == NULL || pvd->vdev_parent == NULL)
122 		return (vd->vdev_psize);
123 
124 	rsize = 0;
125 
126 	for (c = 0; c < pvd->vdev_children; c++) {
127 		cvd = pvd->vdev_child[c];
128 		rsize = MIN(rsize - 1, cvd->vdev_psize - 1) + 1;
129 	}
130 
131 	return (rsize);
132 }
133 
134 vdev_t *
135 vdev_lookup_top(spa_t *spa, uint64_t vdev)
136 {
137 	vdev_t *rvd = spa->spa_root_vdev;
138 
139 	if (vdev < rvd->vdev_children)
140 		return (rvd->vdev_child[vdev]);
141 
142 	return (NULL);
143 }
144 
145 vdev_t *
146 vdev_lookup_by_guid(vdev_t *vd, uint64_t guid)
147 {
148 	int c;
149 	vdev_t *mvd;
150 
151 	if (vd->vdev_guid == guid)
152 		return (vd);
153 
154 	for (c = 0; c < vd->vdev_children; c++)
155 		if ((mvd = vdev_lookup_by_guid(vd->vdev_child[c], guid)) !=
156 		    NULL)
157 			return (mvd);
158 
159 	return (NULL);
160 }
161 
162 void
163 vdev_add_child(vdev_t *pvd, vdev_t *cvd)
164 {
165 	size_t oldsize, newsize;
166 	uint64_t id = cvd->vdev_id;
167 	vdev_t **newchild;
168 
169 	ASSERT(spa_config_held(cvd->vdev_spa, RW_WRITER));
170 	ASSERT(cvd->vdev_parent == NULL);
171 
172 	cvd->vdev_parent = pvd;
173 
174 	if (pvd == NULL)
175 		return;
176 
177 	ASSERT(id >= pvd->vdev_children || pvd->vdev_child[id] == NULL);
178 
179 	oldsize = pvd->vdev_children * sizeof (vdev_t *);
180 	pvd->vdev_children = MAX(pvd->vdev_children, id + 1);
181 	newsize = pvd->vdev_children * sizeof (vdev_t *);
182 
183 	newchild = kmem_zalloc(newsize, KM_SLEEP);
184 	if (pvd->vdev_child != NULL) {
185 		bcopy(pvd->vdev_child, newchild, oldsize);
186 		kmem_free(pvd->vdev_child, oldsize);
187 	}
188 
189 	pvd->vdev_child = newchild;
190 	pvd->vdev_child[id] = cvd;
191 
192 	cvd->vdev_top = (pvd->vdev_top ? pvd->vdev_top: cvd);
193 	ASSERT(cvd->vdev_top->vdev_parent->vdev_parent == NULL);
194 
195 	/*
196 	 * Walk up all ancestors to update guid sum.
197 	 */
198 	for (; pvd != NULL; pvd = pvd->vdev_parent)
199 		pvd->vdev_guid_sum += cvd->vdev_guid_sum;
200 
201 	if (cvd->vdev_ops->vdev_op_leaf)
202 		cvd->vdev_spa->spa_scrub_maxinflight += zfs_scrub_limit;
203 }
204 
205 void
206 vdev_remove_child(vdev_t *pvd, vdev_t *cvd)
207 {
208 	int c;
209 	uint_t id = cvd->vdev_id;
210 
211 	ASSERT(cvd->vdev_parent == pvd);
212 
213 	if (pvd == NULL)
214 		return;
215 
216 	ASSERT(id < pvd->vdev_children);
217 	ASSERT(pvd->vdev_child[id] == cvd);
218 
219 	pvd->vdev_child[id] = NULL;
220 	cvd->vdev_parent = NULL;
221 
222 	for (c = 0; c < pvd->vdev_children; c++)
223 		if (pvd->vdev_child[c])
224 			break;
225 
226 	if (c == pvd->vdev_children) {
227 		kmem_free(pvd->vdev_child, c * sizeof (vdev_t *));
228 		pvd->vdev_child = NULL;
229 		pvd->vdev_children = 0;
230 	}
231 
232 	/*
233 	 * Walk up all ancestors to update guid sum.
234 	 */
235 	for (; pvd != NULL; pvd = pvd->vdev_parent)
236 		pvd->vdev_guid_sum -= cvd->vdev_guid_sum;
237 
238 	if (cvd->vdev_ops->vdev_op_leaf)
239 		cvd->vdev_spa->spa_scrub_maxinflight -= zfs_scrub_limit;
240 }
241 
242 /*
243  * Remove any holes in the child array.
244  */
245 void
246 vdev_compact_children(vdev_t *pvd)
247 {
248 	vdev_t **newchild, *cvd;
249 	int oldc = pvd->vdev_children;
250 	int newc, c;
251 
252 	ASSERT(spa_config_held(pvd->vdev_spa, RW_WRITER));
253 
254 	for (c = newc = 0; c < oldc; c++)
255 		if (pvd->vdev_child[c])
256 			newc++;
257 
258 	newchild = kmem_alloc(newc * sizeof (vdev_t *), KM_SLEEP);
259 
260 	for (c = newc = 0; c < oldc; c++) {
261 		if ((cvd = pvd->vdev_child[c]) != NULL) {
262 			newchild[newc] = cvd;
263 			cvd->vdev_id = newc++;
264 		}
265 	}
266 
267 	kmem_free(pvd->vdev_child, oldc * sizeof (vdev_t *));
268 	pvd->vdev_child = newchild;
269 	pvd->vdev_children = newc;
270 }
271 
272 /*
273  * Allocate and minimally initialize a vdev_t.
274  */
275 static vdev_t *
276 vdev_alloc_common(spa_t *spa, uint_t id, uint64_t guid, vdev_ops_t *ops)
277 {
278 	vdev_t *vd;
279 
280 	vd = kmem_zalloc(sizeof (vdev_t), KM_SLEEP);
281 
282 	if (spa->spa_root_vdev == NULL) {
283 		ASSERT(ops == &vdev_root_ops);
284 		spa->spa_root_vdev = vd;
285 	}
286 
287 	if (guid == 0) {
288 		if (spa->spa_root_vdev == vd) {
289 			/*
290 			 * The root vdev's guid will also be the pool guid,
291 			 * which must be unique among all pools.
292 			 */
293 			while (guid == 0 || spa_guid_exists(guid, 0))
294 				guid = spa_get_random(-1ULL);
295 		} else {
296 			/*
297 			 * Any other vdev's guid must be unique within the pool.
298 			 */
299 			while (guid == 0 ||
300 			    spa_guid_exists(spa_guid(spa), guid))
301 				guid = spa_get_random(-1ULL);
302 		}
303 		ASSERT(!spa_guid_exists(spa_guid(spa), guid));
304 	}
305 
306 	vd->vdev_spa = spa;
307 	vd->vdev_id = id;
308 	vd->vdev_guid = guid;
309 	vd->vdev_guid_sum = guid;
310 	vd->vdev_ops = ops;
311 	vd->vdev_state = VDEV_STATE_CLOSED;
312 
313 	mutex_init(&vd->vdev_dtl_lock, NULL, MUTEX_DEFAULT, NULL);
314 	mutex_init(&vd->vdev_stat_lock, NULL, MUTEX_DEFAULT, NULL);
315 	space_map_create(&vd->vdev_dtl_map, 0, -1ULL, 0, &vd->vdev_dtl_lock);
316 	space_map_create(&vd->vdev_dtl_scrub, 0, -1ULL, 0, &vd->vdev_dtl_lock);
317 	txg_list_create(&vd->vdev_ms_list,
318 	    offsetof(struct metaslab, ms_txg_node));
319 	txg_list_create(&vd->vdev_dtl_list,
320 	    offsetof(struct vdev, vdev_dtl_node));
321 	vd->vdev_stat.vs_timestamp = gethrtime();
322 	vdev_queue_init(vd);
323 	vdev_cache_init(vd);
324 
325 	return (vd);
326 }
327 
328 /*
329  * Allocate a new vdev.  The 'alloctype' is used to control whether we are
330  * creating a new vdev or loading an existing one - the behavior is slightly
331  * different for each case.
332  */
333 int
334 vdev_alloc(spa_t *spa, vdev_t **vdp, nvlist_t *nv, vdev_t *parent, uint_t id,
335     int alloctype)
336 {
337 	vdev_ops_t *ops;
338 	char *type;
339 	uint64_t guid = 0, islog, nparity;
340 	vdev_t *vd;
341 
342 	ASSERT(spa_config_held(spa, RW_WRITER));
343 
344 	if (nvlist_lookup_string(nv, ZPOOL_CONFIG_TYPE, &type) != 0)
345 		return (EINVAL);
346 
347 	if ((ops = vdev_getops(type)) == NULL)
348 		return (EINVAL);
349 
350 	/*
351 	 * If this is a load, get the vdev guid from the nvlist.
352 	 * Otherwise, vdev_alloc_common() will generate one for us.
353 	 */
354 	if (alloctype == VDEV_ALLOC_LOAD) {
355 		uint64_t label_id;
356 
357 		if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_ID, &label_id) ||
358 		    label_id != id)
359 			return (EINVAL);
360 
361 		if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &guid) != 0)
362 			return (EINVAL);
363 	} else if (alloctype == VDEV_ALLOC_SPARE) {
364 		if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &guid) != 0)
365 			return (EINVAL);
366 	}
367 
368 	/*
369 	 * The first allocated vdev must be of type 'root'.
370 	 */
371 	if (ops != &vdev_root_ops && spa->spa_root_vdev == NULL)
372 		return (EINVAL);
373 
374 	/*
375 	 * Determine whether we're a log vdev.
376 	 */
377 	islog = 0;
378 	(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_IS_LOG, &islog);
379 	if (islog && spa_version(spa) < SPA_VERSION_SLOGS)
380 		return (ENOTSUP);
381 
382 	/*
383 	 * Set the nparity property for RAID-Z vdevs.
384 	 */
385 	nparity = -1ULL;
386 	if (ops == &vdev_raidz_ops) {
387 		if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_NPARITY,
388 		    &nparity) == 0) {
389 			/*
390 			 * Currently, we can only support 2 parity devices.
391 			 */
392 			if (nparity == 0 || nparity > 2)
393 				return (EINVAL);
394 			/*
395 			 * Older versions can only support 1 parity device.
396 			 */
397 			if (nparity == 2 &&
398 			    spa_version(spa) < SPA_VERSION_RAID6)
399 				return (ENOTSUP);
400 		} else {
401 			/*
402 			 * We require the parity to be specified for SPAs that
403 			 * support multiple parity levels.
404 			 */
405 			if (spa_version(spa) >= SPA_VERSION_RAID6)
406 				return (EINVAL);
407 			/*
408 			 * Otherwise, we default to 1 parity device for RAID-Z.
409 			 */
410 			nparity = 1;
411 		}
412 	} else {
413 		nparity = 0;
414 	}
415 	ASSERT(nparity != -1ULL);
416 
417 	vd = vdev_alloc_common(spa, id, guid, ops);
418 
419 	vd->vdev_islog = islog;
420 	vd->vdev_nparity = nparity;
421 
422 	if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &vd->vdev_path) == 0)
423 		vd->vdev_path = spa_strdup(vd->vdev_path);
424 	if (nvlist_lookup_string(nv, ZPOOL_CONFIG_DEVID, &vd->vdev_devid) == 0)
425 		vd->vdev_devid = spa_strdup(vd->vdev_devid);
426 	if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PHYS_PATH,
427 	    &vd->vdev_physpath) == 0)
428 		vd->vdev_physpath = spa_strdup(vd->vdev_physpath);
429 
430 	/*
431 	 * Set the whole_disk property.  If it's not specified, leave the value
432 	 * as -1.
433 	 */
434 	if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK,
435 	    &vd->vdev_wholedisk) != 0)
436 		vd->vdev_wholedisk = -1ULL;
437 
438 	/*
439 	 * Look for the 'not present' flag.  This will only be set if the device
440 	 * was not present at the time of import.
441 	 */
442 	(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_NOT_PRESENT,
443 	    &vd->vdev_not_present);
444 
445 	/*
446 	 * Get the alignment requirement.
447 	 */
448 	(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_ASHIFT, &vd->vdev_ashift);
449 
450 	/*
451 	 * If we're a top-level vdev, try to load the allocation parameters.
452 	 */
453 	if (parent && !parent->vdev_parent && alloctype == VDEV_ALLOC_LOAD) {
454 		(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_METASLAB_ARRAY,
455 		    &vd->vdev_ms_array);
456 		(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_METASLAB_SHIFT,
457 		    &vd->vdev_ms_shift);
458 		(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_ASIZE,
459 		    &vd->vdev_asize);
460 	}
461 
462 	/*
463 	 * If we're a leaf vdev, try to load the DTL object and other state.
464 	 */
465 	if (vd->vdev_ops->vdev_op_leaf && alloctype == VDEV_ALLOC_LOAD) {
466 		(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DTL,
467 		    &vd->vdev_dtl.smo_object);
468 		(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_OFFLINE,
469 		    &vd->vdev_offline);
470 		(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_UNSPARE,
471 		    &vd->vdev_unspare);
472 		/*
473 		 * When importing a pool, we want to ignore the persistent fault
474 		 * state, as the diagnosis made on another system may not be
475 		 * valid in the current context.
476 		 */
477 		if (spa->spa_load_state == SPA_LOAD_OPEN) {
478 			(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_FAULTED,
479 			    &vd->vdev_faulted);
480 			(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DEGRADED,
481 			    &vd->vdev_degraded);
482 			(void) nvlist_lookup_uint64(nv, ZPOOL_CONFIG_REMOVED,
483 			    &vd->vdev_removed);
484 		}
485 	}
486 
487 	/*
488 	 * Add ourselves to the parent's list of children.
489 	 */
490 	vdev_add_child(parent, vd);
491 
492 	*vdp = vd;
493 
494 	return (0);
495 }
496 
497 void
498 vdev_free(vdev_t *vd)
499 {
500 	int c;
501 	spa_t *spa = vd->vdev_spa;
502 
503 	/*
504 	 * vdev_free() implies closing the vdev first.  This is simpler than
505 	 * trying to ensure complicated semantics for all callers.
506 	 */
507 	vdev_close(vd);
508 
509 
510 	ASSERT(!list_link_active(&vd->vdev_dirty_node));
511 
512 	/*
513 	 * Free all children.
514 	 */
515 	for (c = 0; c < vd->vdev_children; c++)
516 		vdev_free(vd->vdev_child[c]);
517 
518 	ASSERT(vd->vdev_child == NULL);
519 	ASSERT(vd->vdev_guid_sum == vd->vdev_guid);
520 
521 	/*
522 	 * Discard allocation state.
523 	 */
524 	if (vd == vd->vdev_top)
525 		vdev_metaslab_fini(vd);
526 
527 	ASSERT3U(vd->vdev_stat.vs_space, ==, 0);
528 	ASSERT3U(vd->vdev_stat.vs_dspace, ==, 0);
529 	ASSERT3U(vd->vdev_stat.vs_alloc, ==, 0);
530 
531 	/*
532 	 * Remove this vdev from its parent's child list.
533 	 */
534 	vdev_remove_child(vd->vdev_parent, vd);
535 
536 	ASSERT(vd->vdev_parent == NULL);
537 
538 	/*
539 	 * Clean up vdev structure.
540 	 */
541 	vdev_queue_fini(vd);
542 	vdev_cache_fini(vd);
543 
544 	if (vd->vdev_path)
545 		spa_strfree(vd->vdev_path);
546 	if (vd->vdev_devid)
547 		spa_strfree(vd->vdev_devid);
548 	if (vd->vdev_physpath)
549 		spa_strfree(vd->vdev_physpath);
550 
551 	if (vd->vdev_isspare)
552 		spa_spare_remove(vd);
553 
554 	txg_list_destroy(&vd->vdev_ms_list);
555 	txg_list_destroy(&vd->vdev_dtl_list);
556 	mutex_enter(&vd->vdev_dtl_lock);
557 	space_map_unload(&vd->vdev_dtl_map);
558 	space_map_destroy(&vd->vdev_dtl_map);
559 	space_map_vacate(&vd->vdev_dtl_scrub, NULL, NULL);
560 	space_map_destroy(&vd->vdev_dtl_scrub);
561 	mutex_exit(&vd->vdev_dtl_lock);
562 	mutex_destroy(&vd->vdev_dtl_lock);
563 	mutex_destroy(&vd->vdev_stat_lock);
564 
565 	if (vd == spa->spa_root_vdev)
566 		spa->spa_root_vdev = NULL;
567 
568 	kmem_free(vd, sizeof (vdev_t));
569 }
570 
571 /*
572  * Transfer top-level vdev state from svd to tvd.
573  */
574 static void
575 vdev_top_transfer(vdev_t *svd, vdev_t *tvd)
576 {
577 	spa_t *spa = svd->vdev_spa;
578 	metaslab_t *msp;
579 	vdev_t *vd;
580 	int t;
581 
582 	ASSERT(tvd == tvd->vdev_top);
583 
584 	tvd->vdev_ms_array = svd->vdev_ms_array;
585 	tvd->vdev_ms_shift = svd->vdev_ms_shift;
586 	tvd->vdev_ms_count = svd->vdev_ms_count;
587 
588 	svd->vdev_ms_array = 0;
589 	svd->vdev_ms_shift = 0;
590 	svd->vdev_ms_count = 0;
591 
592 	tvd->vdev_mg = svd->vdev_mg;
593 	tvd->vdev_ms = svd->vdev_ms;
594 
595 	svd->vdev_mg = NULL;
596 	svd->vdev_ms = NULL;
597 
598 	if (tvd->vdev_mg != NULL)
599 		tvd->vdev_mg->mg_vd = tvd;
600 
601 	tvd->vdev_stat.vs_alloc = svd->vdev_stat.vs_alloc;
602 	tvd->vdev_stat.vs_space = svd->vdev_stat.vs_space;
603 	tvd->vdev_stat.vs_dspace = svd->vdev_stat.vs_dspace;
604 
605 	svd->vdev_stat.vs_alloc = 0;
606 	svd->vdev_stat.vs_space = 0;
607 	svd->vdev_stat.vs_dspace = 0;
608 
609 	for (t = 0; t < TXG_SIZE; t++) {
610 		while ((msp = txg_list_remove(&svd->vdev_ms_list, t)) != NULL)
611 			(void) txg_list_add(&tvd->vdev_ms_list, msp, t);
612 		while ((vd = txg_list_remove(&svd->vdev_dtl_list, t)) != NULL)
613 			(void) txg_list_add(&tvd->vdev_dtl_list, vd, t);
614 		if (txg_list_remove_this(&spa->spa_vdev_txg_list, svd, t))
615 			(void) txg_list_add(&spa->spa_vdev_txg_list, tvd, t);
616 	}
617 
618 	if (list_link_active(&svd->vdev_dirty_node)) {
619 		vdev_config_clean(svd);
620 		vdev_config_dirty(tvd);
621 	}
622 
623 	tvd->vdev_deflate_ratio = svd->vdev_deflate_ratio;
624 	svd->vdev_deflate_ratio = 0;
625 
626 	tvd->vdev_islog = svd->vdev_islog;
627 	svd->vdev_islog = 0;
628 }
629 
630 static void
631 vdev_top_update(vdev_t *tvd, vdev_t *vd)
632 {
633 	int c;
634 
635 	if (vd == NULL)
636 		return;
637 
638 	vd->vdev_top = tvd;
639 
640 	for (c = 0; c < vd->vdev_children; c++)
641 		vdev_top_update(tvd, vd->vdev_child[c]);
642 }
643 
644 /*
645  * Add a mirror/replacing vdev above an existing vdev.
646  */
647 vdev_t *
648 vdev_add_parent(vdev_t *cvd, vdev_ops_t *ops)
649 {
650 	spa_t *spa = cvd->vdev_spa;
651 	vdev_t *pvd = cvd->vdev_parent;
652 	vdev_t *mvd;
653 
654 	ASSERT(spa_config_held(spa, RW_WRITER));
655 
656 	mvd = vdev_alloc_common(spa, cvd->vdev_id, 0, ops);
657 
658 	mvd->vdev_asize = cvd->vdev_asize;
659 	mvd->vdev_ashift = cvd->vdev_ashift;
660 	mvd->vdev_state = cvd->vdev_state;
661 
662 	vdev_remove_child(pvd, cvd);
663 	vdev_add_child(pvd, mvd);
664 	cvd->vdev_id = mvd->vdev_children;
665 	vdev_add_child(mvd, cvd);
666 	vdev_top_update(cvd->vdev_top, cvd->vdev_top);
667 
668 	if (mvd == mvd->vdev_top)
669 		vdev_top_transfer(cvd, mvd);
670 
671 	return (mvd);
672 }
673 
674 /*
675  * Remove a 1-way mirror/replacing vdev from the tree.
676  */
677 void
678 vdev_remove_parent(vdev_t *cvd)
679 {
680 	vdev_t *mvd = cvd->vdev_parent;
681 	vdev_t *pvd = mvd->vdev_parent;
682 
683 	ASSERT(spa_config_held(cvd->vdev_spa, RW_WRITER));
684 
685 	ASSERT(mvd->vdev_children == 1);
686 	ASSERT(mvd->vdev_ops == &vdev_mirror_ops ||
687 	    mvd->vdev_ops == &vdev_replacing_ops ||
688 	    mvd->vdev_ops == &vdev_spare_ops);
689 	cvd->vdev_ashift = mvd->vdev_ashift;
690 
691 	vdev_remove_child(mvd, cvd);
692 	vdev_remove_child(pvd, mvd);
693 	cvd->vdev_id = mvd->vdev_id;
694 	vdev_add_child(pvd, cvd);
695 	/*
696 	 * If we created a new toplevel vdev, then we need to change the child's
697 	 * vdev GUID to match the old toplevel vdev.  Otherwise, we could have
698 	 * detached an offline device, and when we go to import the pool we'll
699 	 * think we have two toplevel vdevs, instead of a different version of
700 	 * the same toplevel vdev.
701 	 */
702 	if (cvd->vdev_top == cvd) {
703 		pvd->vdev_guid_sum -= cvd->vdev_guid;
704 		cvd->vdev_guid_sum -= cvd->vdev_guid;
705 		cvd->vdev_guid = mvd->vdev_guid;
706 		cvd->vdev_guid_sum += mvd->vdev_guid;
707 		pvd->vdev_guid_sum += cvd->vdev_guid;
708 	}
709 	vdev_top_update(cvd->vdev_top, cvd->vdev_top);
710 
711 	if (cvd == cvd->vdev_top)
712 		vdev_top_transfer(mvd, cvd);
713 
714 	ASSERT(mvd->vdev_children == 0);
715 	vdev_free(mvd);
716 }
717 
718 int
719 vdev_metaslab_init(vdev_t *vd, uint64_t txg)
720 {
721 	spa_t *spa = vd->vdev_spa;
722 	objset_t *mos = spa->spa_meta_objset;
723 	metaslab_class_t *mc;
724 	uint64_t m;
725 	uint64_t oldc = vd->vdev_ms_count;
726 	uint64_t newc = vd->vdev_asize >> vd->vdev_ms_shift;
727 	metaslab_t **mspp;
728 	int error;
729 
730 	if (vd->vdev_ms_shift == 0)	/* not being allocated from yet */
731 		return (0);
732 
733 	dprintf("%s oldc %llu newc %llu\n", vdev_description(vd), oldc, newc);
734 
735 	ASSERT(oldc <= newc);
736 
737 	if (vd->vdev_islog)
738 		mc = spa->spa_log_class;
739 	else
740 		mc = spa->spa_normal_class;
741 
742 	if (vd->vdev_mg == NULL)
743 		vd->vdev_mg = metaslab_group_create(mc, vd);
744 
745 	mspp = kmem_zalloc(newc * sizeof (*mspp), KM_SLEEP);
746 
747 	if (oldc != 0) {
748 		bcopy(vd->vdev_ms, mspp, oldc * sizeof (*mspp));
749 		kmem_free(vd->vdev_ms, oldc * sizeof (*mspp));
750 	}
751 
752 	vd->vdev_ms = mspp;
753 	vd->vdev_ms_count = newc;
754 
755 	for (m = oldc; m < newc; m++) {
756 		space_map_obj_t smo = { 0, 0, 0 };
757 		if (txg == 0) {
758 			uint64_t object = 0;
759 			error = dmu_read(mos, vd->vdev_ms_array,
760 			    m * sizeof (uint64_t), sizeof (uint64_t), &object);
761 			if (error)
762 				return (error);
763 			if (object != 0) {
764 				dmu_buf_t *db;
765 				error = dmu_bonus_hold(mos, object, FTAG, &db);
766 				if (error)
767 					return (error);
768 				ASSERT3U(db->db_size, >=, sizeof (smo));
769 				bcopy(db->db_data, &smo, sizeof (smo));
770 				ASSERT3U(smo.smo_object, ==, object);
771 				dmu_buf_rele(db, FTAG);
772 			}
773 		}
774 		vd->vdev_ms[m] = metaslab_init(vd->vdev_mg, &smo,
775 		    m << vd->vdev_ms_shift, 1ULL << vd->vdev_ms_shift, txg);
776 	}
777 
778 	return (0);
779 }
780 
781 void
782 vdev_metaslab_fini(vdev_t *vd)
783 {
784 	uint64_t m;
785 	uint64_t count = vd->vdev_ms_count;
786 
787 	if (vd->vdev_ms != NULL) {
788 		for (m = 0; m < count; m++)
789 			if (vd->vdev_ms[m] != NULL)
790 				metaslab_fini(vd->vdev_ms[m]);
791 		kmem_free(vd->vdev_ms, count * sizeof (metaslab_t *));
792 		vd->vdev_ms = NULL;
793 	}
794 }
795 
796 int
797 vdev_probe(vdev_t *vd)
798 {
799 	if (vd == NULL)
800 		return (EINVAL);
801 
802 	/*
803 	 * Right now we only support status checks on the leaf vdevs.
804 	 */
805 	if (vd->vdev_ops->vdev_op_leaf)
806 		return (vd->vdev_ops->vdev_op_probe(vd));
807 
808 	return (0);
809 }
810 
811 /*
812  * Prepare a virtual device for access.
813  */
814 int
815 vdev_open(vdev_t *vd)
816 {
817 	int error;
818 	int c;
819 	uint64_t osize = 0;
820 	uint64_t asize, psize;
821 	uint64_t ashift = 0;
822 
823 	ASSERT(vd->vdev_state == VDEV_STATE_CLOSED ||
824 	    vd->vdev_state == VDEV_STATE_CANT_OPEN ||
825 	    vd->vdev_state == VDEV_STATE_OFFLINE);
826 
827 	if (vd->vdev_fault_mode == VDEV_FAULT_COUNT)
828 		vd->vdev_fault_arg >>= 1;
829 	else
830 		vd->vdev_fault_mode = VDEV_FAULT_NONE;
831 
832 	vd->vdev_stat.vs_aux = VDEV_AUX_NONE;
833 
834 	if (!vd->vdev_removed && vd->vdev_faulted) {
835 		ASSERT(vd->vdev_children == 0);
836 		vdev_set_state(vd, B_TRUE, VDEV_STATE_FAULTED,
837 		    VDEV_AUX_ERR_EXCEEDED);
838 		return (ENXIO);
839 	} else if (vd->vdev_offline) {
840 		ASSERT(vd->vdev_children == 0);
841 		vdev_set_state(vd, B_TRUE, VDEV_STATE_OFFLINE, VDEV_AUX_NONE);
842 		return (ENXIO);
843 	}
844 
845 	error = vd->vdev_ops->vdev_op_open(vd, &osize, &ashift);
846 
847 	if (zio_injection_enabled && error == 0)
848 		error = zio_handle_device_injection(vd, ENXIO);
849 
850 	if (error) {
851 		if (vd->vdev_removed &&
852 		    vd->vdev_stat.vs_aux != VDEV_AUX_OPEN_FAILED)
853 			vd->vdev_removed = B_FALSE;
854 
855 		vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
856 		    vd->vdev_stat.vs_aux);
857 		return (error);
858 	}
859 
860 	vd->vdev_removed = B_FALSE;
861 
862 	if (vd->vdev_degraded) {
863 		ASSERT(vd->vdev_children == 0);
864 		vdev_set_state(vd, B_TRUE, VDEV_STATE_DEGRADED,
865 		    VDEV_AUX_ERR_EXCEEDED);
866 	} else {
867 		vd->vdev_state = VDEV_STATE_HEALTHY;
868 	}
869 
870 	for (c = 0; c < vd->vdev_children; c++)
871 		if (vd->vdev_child[c]->vdev_state != VDEV_STATE_HEALTHY) {
872 			vdev_set_state(vd, B_TRUE, VDEV_STATE_DEGRADED,
873 			    VDEV_AUX_NONE);
874 			break;
875 		}
876 
877 	osize = P2ALIGN(osize, (uint64_t)sizeof (vdev_label_t));
878 
879 	if (vd->vdev_children == 0) {
880 		if (osize < SPA_MINDEVSIZE) {
881 			vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
882 			    VDEV_AUX_TOO_SMALL);
883 			return (EOVERFLOW);
884 		}
885 		psize = osize;
886 		asize = osize - (VDEV_LABEL_START_SIZE + VDEV_LABEL_END_SIZE);
887 	} else {
888 		if (vd->vdev_parent != NULL && osize < SPA_MINDEVSIZE -
889 		    (VDEV_LABEL_START_SIZE + VDEV_LABEL_END_SIZE)) {
890 			vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
891 			    VDEV_AUX_TOO_SMALL);
892 			return (EOVERFLOW);
893 		}
894 		psize = 0;
895 		asize = osize;
896 	}
897 
898 	vd->vdev_psize = psize;
899 
900 	if (vd->vdev_asize == 0) {
901 		/*
902 		 * This is the first-ever open, so use the computed values.
903 		 * For testing purposes, a higher ashift can be requested.
904 		 */
905 		vd->vdev_asize = asize;
906 		vd->vdev_ashift = MAX(ashift, vd->vdev_ashift);
907 	} else {
908 		/*
909 		 * Make sure the alignment requirement hasn't increased.
910 		 */
911 		if (ashift > vd->vdev_top->vdev_ashift) {
912 			vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
913 			    VDEV_AUX_BAD_LABEL);
914 			return (EINVAL);
915 		}
916 
917 		/*
918 		 * Make sure the device hasn't shrunk.
919 		 */
920 		if (asize < vd->vdev_asize) {
921 			vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
922 			    VDEV_AUX_BAD_LABEL);
923 			return (EINVAL);
924 		}
925 
926 		/*
927 		 * If all children are healthy and the asize has increased,
928 		 * then we've experienced dynamic LUN growth.
929 		 */
930 		if (vd->vdev_state == VDEV_STATE_HEALTHY &&
931 		    asize > vd->vdev_asize) {
932 			vd->vdev_asize = asize;
933 		}
934 	}
935 
936 	/*
937 	 * Ensure we can issue some IO before declaring the
938 	 * vdev open for business.
939 	 */
940 	error = vdev_probe(vd);
941 	if (error) {
942 		vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
943 		    VDEV_AUX_OPEN_FAILED);
944 		return (error);
945 	}
946 
947 	/*
948 	 * If this is a top-level vdev, compute the raidz-deflation
949 	 * ratio.  Note, we hard-code in 128k (1<<17) because it is the
950 	 * current "typical" blocksize.  Even if SPA_MAXBLOCKSIZE
951 	 * changes, this algorithm must never change, or we will
952 	 * inconsistently account for existing bp's.
953 	 */
954 	if (vd->vdev_top == vd) {
955 		vd->vdev_deflate_ratio = (1<<17) /
956 		    (vdev_psize_to_asize(vd, 1<<17) >> SPA_MINBLOCKSHIFT);
957 	}
958 
959 	/*
960 	 * This allows the ZFS DE to close cases appropriately.  If a device
961 	 * goes away and later returns, we want to close the associated case.
962 	 * But it's not enough to simply post this only when a device goes from
963 	 * CANT_OPEN -> HEALTHY.  If we reboot the system and the device is
964 	 * back, we also need to close the case (otherwise we will try to replay
965 	 * it).  So we have to post this notifier every time.  Since this only
966 	 * occurs during pool open or error recovery, this should not be an
967 	 * issue.
968 	 */
969 	zfs_post_ok(vd->vdev_spa, vd);
970 
971 	return (0);
972 }
973 
974 /*
975  * Called once the vdevs are all opened, this routine validates the label
976  * contents.  This needs to be done before vdev_load() so that we don't
977  * inadvertently do repair I/Os to the wrong device.
978  *
979  * This function will only return failure if one of the vdevs indicates that it
980  * has since been destroyed or exported.  This is only possible if
981  * /etc/zfs/zpool.cache was readonly at the time.  Otherwise, the vdev state
982  * will be updated but the function will return 0.
983  */
984 int
985 vdev_validate(vdev_t *vd)
986 {
987 	spa_t *spa = vd->vdev_spa;
988 	int c;
989 	nvlist_t *label;
990 	uint64_t guid;
991 	uint64_t state;
992 
993 	for (c = 0; c < vd->vdev_children; c++)
994 		if (vdev_validate(vd->vdev_child[c]) != 0)
995 			return (EBADF);
996 
997 	/*
998 	 * If the device has already failed, or was marked offline, don't do
999 	 * any further validation.  Otherwise, label I/O will fail and we will
1000 	 * overwrite the previous state.
1001 	 */
1002 	if (vd->vdev_ops->vdev_op_leaf && !vdev_is_dead(vd)) {
1003 
1004 		if ((label = vdev_label_read_config(vd)) == NULL) {
1005 			vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
1006 			    VDEV_AUX_BAD_LABEL);
1007 			return (0);
1008 		}
1009 
1010 		if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID,
1011 		    &guid) != 0 || guid != spa_guid(spa)) {
1012 			vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
1013 			    VDEV_AUX_CORRUPT_DATA);
1014 			nvlist_free(label);
1015 			return (0);
1016 		}
1017 
1018 		if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID,
1019 		    &guid) != 0 || guid != vd->vdev_guid) {
1020 			vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
1021 			    VDEV_AUX_CORRUPT_DATA);
1022 			nvlist_free(label);
1023 			return (0);
1024 		}
1025 
1026 		if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_STATE,
1027 		    &state) != 0) {
1028 			vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
1029 			    VDEV_AUX_CORRUPT_DATA);
1030 			nvlist_free(label);
1031 			return (0);
1032 		}
1033 
1034 		nvlist_free(label);
1035 
1036 		if (spa->spa_load_state == SPA_LOAD_OPEN &&
1037 		    state != POOL_STATE_ACTIVE)
1038 			return (EBADF);
1039 	}
1040 
1041 	/*
1042 	 * If we were able to open and validate a vdev that was previously
1043 	 * marked permanently unavailable, clear that state now.
1044 	 */
1045 	if (vd->vdev_not_present)
1046 		vd->vdev_not_present = 0;
1047 
1048 	return (0);
1049 }
1050 
1051 /*
1052  * Close a virtual device.
1053  */
1054 void
1055 vdev_close(vdev_t *vd)
1056 {
1057 	vd->vdev_ops->vdev_op_close(vd);
1058 
1059 	vdev_cache_purge(vd);
1060 
1061 	/*
1062 	 * We record the previous state before we close it, so  that if we are
1063 	 * doing a reopen(), we don't generate FMA ereports if we notice that
1064 	 * it's still faulted.
1065 	 */
1066 	vd->vdev_prevstate = vd->vdev_state;
1067 
1068 	if (vd->vdev_offline)
1069 		vd->vdev_state = VDEV_STATE_OFFLINE;
1070 	else
1071 		vd->vdev_state = VDEV_STATE_CLOSED;
1072 	vd->vdev_stat.vs_aux = VDEV_AUX_NONE;
1073 }
1074 
1075 void
1076 vdev_reopen(vdev_t *vd)
1077 {
1078 	spa_t *spa = vd->vdev_spa;
1079 
1080 	ASSERT(spa_config_held(spa, RW_WRITER));
1081 
1082 	vdev_close(vd);
1083 	(void) vdev_open(vd);
1084 
1085 	/*
1086 	 * Call vdev_validate() here to make sure we have the same device.
1087 	 * Otherwise, a device with an invalid label could be successfully
1088 	 * opened in response to vdev_reopen().
1089 	 */
1090 	(void) vdev_validate(vd);
1091 
1092 	/*
1093 	 * Reassess parent vdev's health.
1094 	 */
1095 	vdev_propagate_state(vd);
1096 }
1097 
1098 int
1099 vdev_create(vdev_t *vd, uint64_t txg, boolean_t isreplacing)
1100 {
1101 	int error;
1102 
1103 	/*
1104 	 * Normally, partial opens (e.g. of a mirror) are allowed.
1105 	 * For a create, however, we want to fail the request if
1106 	 * there are any components we can't open.
1107 	 */
1108 	error = vdev_open(vd);
1109 
1110 	if (error || vd->vdev_state != VDEV_STATE_HEALTHY) {
1111 		vdev_close(vd);
1112 		return (error ? error : ENXIO);
1113 	}
1114 
1115 	/*
1116 	 * Recursively initialize all labels.
1117 	 */
1118 	if ((error = vdev_label_init(vd, txg, isreplacing ?
1119 	    VDEV_LABEL_REPLACE : VDEV_LABEL_CREATE)) != 0) {
1120 		vdev_close(vd);
1121 		return (error);
1122 	}
1123 
1124 	return (0);
1125 }
1126 
1127 /*
1128  * The is the latter half of vdev_create().  It is distinct because it
1129  * involves initiating transactions in order to do metaslab creation.
1130  * For creation, we want to try to create all vdevs at once and then undo it
1131  * if anything fails; this is much harder if we have pending transactions.
1132  */
1133 void
1134 vdev_init(vdev_t *vd, uint64_t txg)
1135 {
1136 	/*
1137 	 * Aim for roughly 200 metaslabs per vdev.
1138 	 */
1139 	vd->vdev_ms_shift = highbit(vd->vdev_asize / 200);
1140 	vd->vdev_ms_shift = MAX(vd->vdev_ms_shift, SPA_MAXBLOCKSHIFT);
1141 
1142 	/*
1143 	 * Initialize the vdev's metaslabs.  This can't fail because
1144 	 * there's nothing to read when creating all new metaslabs.
1145 	 */
1146 	VERIFY(vdev_metaslab_init(vd, txg) == 0);
1147 }
1148 
1149 void
1150 vdev_dirty(vdev_t *vd, int flags, void *arg, uint64_t txg)
1151 {
1152 	ASSERT(vd == vd->vdev_top);
1153 	ASSERT(ISP2(flags));
1154 
1155 	if (flags & VDD_METASLAB)
1156 		(void) txg_list_add(&vd->vdev_ms_list, arg, txg);
1157 
1158 	if (flags & VDD_DTL)
1159 		(void) txg_list_add(&vd->vdev_dtl_list, arg, txg);
1160 
1161 	(void) txg_list_add(&vd->vdev_spa->spa_vdev_txg_list, vd, txg);
1162 }
1163 
1164 void
1165 vdev_dtl_dirty(space_map_t *sm, uint64_t txg, uint64_t size)
1166 {
1167 	mutex_enter(sm->sm_lock);
1168 	if (!space_map_contains(sm, txg, size))
1169 		space_map_add(sm, txg, size);
1170 	mutex_exit(sm->sm_lock);
1171 }
1172 
1173 int
1174 vdev_dtl_contains(space_map_t *sm, uint64_t txg, uint64_t size)
1175 {
1176 	int dirty;
1177 
1178 	/*
1179 	 * Quick test without the lock -- covers the common case that
1180 	 * there are no dirty time segments.
1181 	 */
1182 	if (sm->sm_space == 0)
1183 		return (0);
1184 
1185 	mutex_enter(sm->sm_lock);
1186 	dirty = space_map_contains(sm, txg, size);
1187 	mutex_exit(sm->sm_lock);
1188 
1189 	return (dirty);
1190 }
1191 
1192 /*
1193  * Reassess DTLs after a config change or scrub completion.
1194  */
1195 void
1196 vdev_dtl_reassess(vdev_t *vd, uint64_t txg, uint64_t scrub_txg, int scrub_done)
1197 {
1198 	spa_t *spa = vd->vdev_spa;
1199 	int c;
1200 
1201 	ASSERT(spa_config_held(spa, RW_WRITER));
1202 
1203 	if (vd->vdev_children == 0) {
1204 		mutex_enter(&vd->vdev_dtl_lock);
1205 		/*
1206 		 * We're successfully scrubbed everything up to scrub_txg.
1207 		 * Therefore, excise all old DTLs up to that point, then
1208 		 * fold in the DTLs for everything we couldn't scrub.
1209 		 */
1210 		if (scrub_txg != 0) {
1211 			space_map_excise(&vd->vdev_dtl_map, 0, scrub_txg);
1212 			space_map_union(&vd->vdev_dtl_map, &vd->vdev_dtl_scrub);
1213 		}
1214 		if (scrub_done)
1215 			space_map_vacate(&vd->vdev_dtl_scrub, NULL, NULL);
1216 		mutex_exit(&vd->vdev_dtl_lock);
1217 		if (txg != 0)
1218 			vdev_dirty(vd->vdev_top, VDD_DTL, vd, txg);
1219 		return;
1220 	}
1221 
1222 	/*
1223 	 * Make sure the DTLs are always correct under the scrub lock.
1224 	 */
1225 	if (vd == spa->spa_root_vdev)
1226 		mutex_enter(&spa->spa_scrub_lock);
1227 
1228 	mutex_enter(&vd->vdev_dtl_lock);
1229 	space_map_vacate(&vd->vdev_dtl_map, NULL, NULL);
1230 	space_map_vacate(&vd->vdev_dtl_scrub, NULL, NULL);
1231 	mutex_exit(&vd->vdev_dtl_lock);
1232 
1233 	for (c = 0; c < vd->vdev_children; c++) {
1234 		vdev_t *cvd = vd->vdev_child[c];
1235 		vdev_dtl_reassess(cvd, txg, scrub_txg, scrub_done);
1236 		mutex_enter(&vd->vdev_dtl_lock);
1237 		space_map_union(&vd->vdev_dtl_map, &cvd->vdev_dtl_map);
1238 		space_map_union(&vd->vdev_dtl_scrub, &cvd->vdev_dtl_scrub);
1239 		mutex_exit(&vd->vdev_dtl_lock);
1240 	}
1241 
1242 	if (vd == spa->spa_root_vdev)
1243 		mutex_exit(&spa->spa_scrub_lock);
1244 }
1245 
1246 static int
1247 vdev_dtl_load(vdev_t *vd)
1248 {
1249 	spa_t *spa = vd->vdev_spa;
1250 	space_map_obj_t *smo = &vd->vdev_dtl;
1251 	objset_t *mos = spa->spa_meta_objset;
1252 	dmu_buf_t *db;
1253 	int error;
1254 
1255 	ASSERT(vd->vdev_children == 0);
1256 
1257 	if (smo->smo_object == 0)
1258 		return (0);
1259 
1260 	if ((error = dmu_bonus_hold(mos, smo->smo_object, FTAG, &db)) != 0)
1261 		return (error);
1262 
1263 	ASSERT3U(db->db_size, >=, sizeof (*smo));
1264 	bcopy(db->db_data, smo, sizeof (*smo));
1265 	dmu_buf_rele(db, FTAG);
1266 
1267 	mutex_enter(&vd->vdev_dtl_lock);
1268 	error = space_map_load(&vd->vdev_dtl_map, NULL, SM_ALLOC, smo, mos);
1269 	mutex_exit(&vd->vdev_dtl_lock);
1270 
1271 	return (error);
1272 }
1273 
1274 void
1275 vdev_dtl_sync(vdev_t *vd, uint64_t txg)
1276 {
1277 	spa_t *spa = vd->vdev_spa;
1278 	space_map_obj_t *smo = &vd->vdev_dtl;
1279 	space_map_t *sm = &vd->vdev_dtl_map;
1280 	objset_t *mos = spa->spa_meta_objset;
1281 	space_map_t smsync;
1282 	kmutex_t smlock;
1283 	dmu_buf_t *db;
1284 	dmu_tx_t *tx;
1285 
1286 	dprintf("%s in txg %llu pass %d\n",
1287 	    vdev_description(vd), (u_longlong_t)txg, spa_sync_pass(spa));
1288 
1289 	tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg);
1290 
1291 	if (vd->vdev_detached) {
1292 		if (smo->smo_object != 0) {
1293 			int err = dmu_object_free(mos, smo->smo_object, tx);
1294 			ASSERT3U(err, ==, 0);
1295 			smo->smo_object = 0;
1296 		}
1297 		dmu_tx_commit(tx);
1298 		dprintf("detach %s committed in txg %llu\n",
1299 		    vdev_description(vd), txg);
1300 		return;
1301 	}
1302 
1303 	if (smo->smo_object == 0) {
1304 		ASSERT(smo->smo_objsize == 0);
1305 		ASSERT(smo->smo_alloc == 0);
1306 		smo->smo_object = dmu_object_alloc(mos,
1307 		    DMU_OT_SPACE_MAP, 1 << SPACE_MAP_BLOCKSHIFT,
1308 		    DMU_OT_SPACE_MAP_HEADER, sizeof (*smo), tx);
1309 		ASSERT(smo->smo_object != 0);
1310 		vdev_config_dirty(vd->vdev_top);
1311 	}
1312 
1313 	mutex_init(&smlock, NULL, MUTEX_DEFAULT, NULL);
1314 
1315 	space_map_create(&smsync, sm->sm_start, sm->sm_size, sm->sm_shift,
1316 	    &smlock);
1317 
1318 	mutex_enter(&smlock);
1319 
1320 	mutex_enter(&vd->vdev_dtl_lock);
1321 	space_map_walk(sm, space_map_add, &smsync);
1322 	mutex_exit(&vd->vdev_dtl_lock);
1323 
1324 	space_map_truncate(smo, mos, tx);
1325 	space_map_sync(&smsync, SM_ALLOC, smo, mos, tx);
1326 
1327 	space_map_destroy(&smsync);
1328 
1329 	mutex_exit(&smlock);
1330 	mutex_destroy(&smlock);
1331 
1332 	VERIFY(0 == dmu_bonus_hold(mos, smo->smo_object, FTAG, &db));
1333 	dmu_buf_will_dirty(db, tx);
1334 	ASSERT3U(db->db_size, >=, sizeof (*smo));
1335 	bcopy(smo, db->db_data, sizeof (*smo));
1336 	dmu_buf_rele(db, FTAG);
1337 
1338 	dmu_tx_commit(tx);
1339 }
1340 
1341 void
1342 vdev_load(vdev_t *vd)
1343 {
1344 	int c;
1345 
1346 	/*
1347 	 * Recursively load all children.
1348 	 */
1349 	for (c = 0; c < vd->vdev_children; c++)
1350 		vdev_load(vd->vdev_child[c]);
1351 
1352 	/*
1353 	 * If this is a top-level vdev, initialize its metaslabs.
1354 	 */
1355 	if (vd == vd->vdev_top &&
1356 	    (vd->vdev_ashift == 0 || vd->vdev_asize == 0 ||
1357 	    vdev_metaslab_init(vd, 0) != 0))
1358 		vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
1359 		    VDEV_AUX_CORRUPT_DATA);
1360 
1361 	/*
1362 	 * If this is a leaf vdev, load its DTL.
1363 	 */
1364 	if (vd->vdev_ops->vdev_op_leaf && vdev_dtl_load(vd) != 0)
1365 		vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
1366 		    VDEV_AUX_CORRUPT_DATA);
1367 }
1368 
1369 /*
1370  * This special case of vdev_spare() is used for hot spares.  It's sole purpose
1371  * it to set the vdev state for the associated vdev.  To do this, we make sure
1372  * that we can open the underlying device, then try to read the label, and make
1373  * sure that the label is sane and that it hasn't been repurposed to another
1374  * pool.
1375  */
1376 int
1377 vdev_validate_spare(vdev_t *vd)
1378 {
1379 	nvlist_t *label;
1380 	uint64_t guid, version;
1381 	uint64_t state;
1382 
1383 	if ((label = vdev_label_read_config(vd)) == NULL) {
1384 		vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
1385 		    VDEV_AUX_CORRUPT_DATA);
1386 		return (-1);
1387 	}
1388 
1389 	if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_VERSION, &version) != 0 ||
1390 	    version > SPA_VERSION ||
1391 	    nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID, &guid) != 0 ||
1392 	    guid != vd->vdev_guid ||
1393 	    nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_STATE, &state) != 0) {
1394 		vdev_set_state(vd, B_TRUE, VDEV_STATE_CANT_OPEN,
1395 		    VDEV_AUX_CORRUPT_DATA);
1396 		nvlist_free(label);
1397 		return (-1);
1398 	}
1399 
1400 	spa_spare_add(vd);
1401 
1402 	/*
1403 	 * We don't actually check the pool state here.  If it's in fact in
1404 	 * use by another pool, we update this fact on the fly when requested.
1405 	 */
1406 	nvlist_free(label);
1407 	return (0);
1408 }
1409 
1410 void
1411 vdev_sync_done(vdev_t *vd, uint64_t txg)
1412 {
1413 	metaslab_t *msp;
1414 
1415 	dprintf("%s txg %llu\n", vdev_description(vd), txg);
1416 
1417 	while (msp = txg_list_remove(&vd->vdev_ms_list, TXG_CLEAN(txg)))
1418 		metaslab_sync_done(msp, txg);
1419 }
1420 
1421 void
1422 vdev_sync(vdev_t *vd, uint64_t txg)
1423 {
1424 	spa_t *spa = vd->vdev_spa;
1425 	vdev_t *lvd;
1426 	metaslab_t *msp;
1427 	dmu_tx_t *tx;
1428 
1429 	dprintf("%s txg %llu pass %d\n",
1430 	    vdev_description(vd), (u_longlong_t)txg, spa_sync_pass(spa));
1431 
1432 	if (vd->vdev_ms_array == 0 && vd->vdev_ms_shift != 0) {
1433 		ASSERT(vd == vd->vdev_top);
1434 		tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg);
1435 		vd->vdev_ms_array = dmu_object_alloc(spa->spa_meta_objset,
1436 		    DMU_OT_OBJECT_ARRAY, 0, DMU_OT_NONE, 0, tx);
1437 		ASSERT(vd->vdev_ms_array != 0);
1438 		vdev_config_dirty(vd);
1439 		dmu_tx_commit(tx);
1440 	}
1441 
1442 	while ((msp = txg_list_remove(&vd->vdev_ms_list, txg)) != NULL) {
1443 		metaslab_sync(msp, txg);
1444 		(void) txg_list_add(&vd->vdev_ms_list, msp, TXG_CLEAN(txg));
1445 	}
1446 
1447 	while ((lvd = txg_list_remove(&vd->vdev_dtl_list, txg)) != NULL)
1448 		vdev_dtl_sync(lvd, txg);
1449 
1450 	(void) txg_list_add(&spa->spa_vdev_txg_list, vd, TXG_CLEAN(txg));
1451 }
1452 
1453 uint64_t
1454 vdev_psize_to_asize(vdev_t *vd, uint64_t psize)
1455 {
1456 	return (vd->vdev_ops->vdev_op_asize(vd, psize));
1457 }
1458 
1459 void
1460 vdev_io_start(zio_t *zio)
1461 {
1462 	zio->io_vd->vdev_ops->vdev_op_io_start(zio);
1463 }
1464 
1465 void
1466 vdev_io_done(zio_t *zio)
1467 {
1468 	zio->io_vd->vdev_ops->vdev_op_io_done(zio);
1469 }
1470 
1471 const char *
1472 vdev_description(vdev_t *vd)
1473 {
1474 	if (vd == NULL || vd->vdev_ops == NULL)
1475 		return ("<unknown>");
1476 
1477 	if (vd->vdev_path != NULL)
1478 		return (vd->vdev_path);
1479 
1480 	if (vd->vdev_parent == NULL)
1481 		return (spa_name(vd->vdev_spa));
1482 
1483 	return (vd->vdev_ops->vdev_op_type);
1484 }
1485 
1486 /*
1487  * Mark the given vdev faulted.  A faulted vdev behaves as if the device could
1488  * not be opened, and no I/O is attempted.
1489  */
1490 int
1491 vdev_fault(spa_t *spa, uint64_t guid)
1492 {
1493 	vdev_t *rvd, *vd;
1494 	uint64_t txg;
1495 
1496 	/*
1497 	 * Disregard a vdev fault request if the pool has
1498 	 * experienced a complete failure.
1499 	 *
1500 	 * XXX - We do this here so that we don't hold the
1501 	 * spa_namespace_lock in the event that we can't get
1502 	 * the RW_WRITER spa_config_lock.
1503 	 */
1504 	if (spa_state(spa) == POOL_STATE_IO_FAILURE)
1505 		return (EIO);
1506 
1507 	txg = spa_vdev_enter(spa);
1508 
1509 	rvd = spa->spa_root_vdev;
1510 
1511 	if ((vd = vdev_lookup_by_guid(rvd, guid)) == NULL)
1512 		return (spa_vdev_exit(spa, NULL, txg, ENODEV));
1513 	if (!vd->vdev_ops->vdev_op_leaf)
1514 		return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
1515 
1516 	/*
1517 	 * Faulted state takes precedence over degraded.
1518 	 */
1519 	vd->vdev_faulted = 1ULL;
1520 	vd->vdev_degraded = 0ULL;
1521 	vdev_set_state(vd, B_FALSE, VDEV_STATE_FAULTED,
1522 	    VDEV_AUX_ERR_EXCEEDED);
1523 
1524 	/*
1525 	 * If marking the vdev as faulted cause the toplevel vdev to become
1526 	 * unavailable, then back off and simply mark the vdev as degraded
1527 	 * instead.
1528 	 */
1529 	if (vdev_is_dead(vd->vdev_top)) {
1530 		vd->vdev_degraded = 1ULL;
1531 		vd->vdev_faulted = 0ULL;
1532 
1533 		/*
1534 		 * If we reopen the device and it's not dead, only then do we
1535 		 * mark it degraded.
1536 		 */
1537 		vdev_reopen(vd);
1538 
1539 		if (vdev_readable(vd)) {
1540 			vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED,
1541 			    VDEV_AUX_ERR_EXCEEDED);
1542 		}
1543 	}
1544 
1545 	vdev_config_dirty(vd->vdev_top);
1546 
1547 	(void) spa_vdev_exit(spa, NULL, txg, 0);
1548 
1549 	return (0);
1550 }
1551 
1552 /*
1553  * Mark the given vdev degraded.  A degraded vdev is purely an indication to the
1554  * user that something is wrong.  The vdev continues to operate as normal as far
1555  * as I/O is concerned.
1556  */
1557 int
1558 vdev_degrade(spa_t *spa, uint64_t guid)
1559 {
1560 	vdev_t *rvd, *vd;
1561 	uint64_t txg;
1562 
1563 	/*
1564 	 * Disregard a vdev fault request if the pool has
1565 	 * experienced a complete failure.
1566 	 *
1567 	 * XXX - We do this here so that we don't hold the
1568 	 * spa_namespace_lock in the event that we can't get
1569 	 * the RW_WRITER spa_config_lock.
1570 	 */
1571 	if (spa_state(spa) == POOL_STATE_IO_FAILURE)
1572 		return (EIO);
1573 
1574 	txg = spa_vdev_enter(spa);
1575 
1576 	rvd = spa->spa_root_vdev;
1577 
1578 	if ((vd = vdev_lookup_by_guid(rvd, guid)) == NULL)
1579 		return (spa_vdev_exit(spa, NULL, txg, ENODEV));
1580 	if (!vd->vdev_ops->vdev_op_leaf)
1581 		return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
1582 
1583 	/*
1584 	 * If the vdev is already faulted, then don't do anything.
1585 	 */
1586 	if (vd->vdev_faulted || vd->vdev_degraded) {
1587 		(void) spa_vdev_exit(spa, NULL, txg, 0);
1588 		return (0);
1589 	}
1590 
1591 	vd->vdev_degraded = 1ULL;
1592 	if (!vdev_is_dead(vd))
1593 		vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED,
1594 		    VDEV_AUX_ERR_EXCEEDED);
1595 	vdev_config_dirty(vd->vdev_top);
1596 
1597 	(void) spa_vdev_exit(spa, NULL, txg, 0);
1598 
1599 	return (0);
1600 }
1601 
1602 /*
1603  * Online the given vdev.  If 'unspare' is set, it implies two things.  First,
1604  * any attached spare device should be detached when the device finishes
1605  * resilvering.  Second, the online should be treated like a 'test' online case,
1606  * so no FMA events are generated if the device fails to open.
1607  */
1608 int
1609 vdev_online(spa_t *spa, uint64_t guid, uint64_t flags,
1610     vdev_state_t *newstate)
1611 {
1612 	vdev_t *rvd, *vd;
1613 	uint64_t txg;
1614 
1615 	/*
1616 	 * Disregard a vdev fault request if the pool has
1617 	 * experienced a complete failure.
1618 	 *
1619 	 * XXX - We do this here so that we don't hold the
1620 	 * spa_namespace_lock in the event that we can't get
1621 	 * the RW_WRITER spa_config_lock.
1622 	 */
1623 	if (spa_state(spa) == POOL_STATE_IO_FAILURE)
1624 		return (EIO);
1625 
1626 	txg = spa_vdev_enter(spa);
1627 
1628 	rvd = spa->spa_root_vdev;
1629 
1630 	if ((vd = vdev_lookup_by_guid(rvd, guid)) == NULL)
1631 		return (spa_vdev_exit(spa, NULL, txg, ENODEV));
1632 
1633 	if (!vd->vdev_ops->vdev_op_leaf)
1634 		return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
1635 
1636 	vd->vdev_offline = B_FALSE;
1637 	vd->vdev_tmpoffline = B_FALSE;
1638 	vd->vdev_checkremove = (flags & ZFS_ONLINE_CHECKREMOVE) ?
1639 	    B_TRUE : B_FALSE;
1640 	vd->vdev_forcefault = (flags & ZFS_ONLINE_FORCEFAULT) ?
1641 	    B_TRUE : B_FALSE;
1642 	vdev_reopen(vd->vdev_top);
1643 	vd->vdev_checkremove = vd->vdev_forcefault = B_FALSE;
1644 
1645 	if (newstate)
1646 		*newstate = vd->vdev_state;
1647 	if ((flags & ZFS_ONLINE_UNSPARE) &&
1648 	    !vdev_is_dead(vd) && vd->vdev_parent &&
1649 	    vd->vdev_parent->vdev_ops == &vdev_spare_ops &&
1650 	    vd->vdev_parent->vdev_child[0] == vd)
1651 		vd->vdev_unspare = B_TRUE;
1652 
1653 	vdev_config_dirty(vd->vdev_top);
1654 
1655 	(void) spa_vdev_exit(spa, NULL, txg, 0);
1656 
1657 	/*
1658 	 * Must hold spa_namespace_lock in order to post resilver sysevent
1659 	 * w/pool name.
1660 	 */
1661 	mutex_enter(&spa_namespace_lock);
1662 	VERIFY(spa_scrub(spa, POOL_SCRUB_RESILVER, B_TRUE) == 0);
1663 	mutex_exit(&spa_namespace_lock);
1664 
1665 	return (0);
1666 }
1667 
1668 int
1669 vdev_offline(spa_t *spa, uint64_t guid, uint64_t flags)
1670 {
1671 	vdev_t *rvd, *vd;
1672 	uint64_t txg;
1673 
1674 	/*
1675 	 * Disregard a vdev fault request if the pool has
1676 	 * experienced a complete failure.
1677 	 *
1678 	 * XXX - We do this here so that we don't hold the
1679 	 * spa_namespace_lock in the event that we can't get
1680 	 * the RW_WRITER spa_config_lock.
1681 	 */
1682 	if (spa_state(spa) == POOL_STATE_IO_FAILURE)
1683 		return (EIO);
1684 
1685 	txg = spa_vdev_enter(spa);
1686 
1687 	rvd = spa->spa_root_vdev;
1688 
1689 	if ((vd = vdev_lookup_by_guid(rvd, guid)) == NULL)
1690 		return (spa_vdev_exit(spa, NULL, txg, ENODEV));
1691 
1692 	if (!vd->vdev_ops->vdev_op_leaf)
1693 		return (spa_vdev_exit(spa, NULL, txg, ENOTSUP));
1694 
1695 	/*
1696 	 * If the device isn't already offline, try to offline it.
1697 	 */
1698 	if (!vd->vdev_offline) {
1699 		/*
1700 		 * If this device's top-level vdev has a non-empty DTL,
1701 		 * don't allow the device to be offlined.
1702 		 *
1703 		 * XXX -- make this more precise by allowing the offline
1704 		 * as long as the remaining devices don't have any DTL holes.
1705 		 */
1706 		if (vd->vdev_top->vdev_dtl_map.sm_space != 0)
1707 			return (spa_vdev_exit(spa, NULL, txg, EBUSY));
1708 
1709 		/*
1710 		 * Offline this device and reopen its top-level vdev.
1711 		 * If this action results in the top-level vdev becoming
1712 		 * unusable, undo it and fail the request.
1713 		 */
1714 		vd->vdev_offline = B_TRUE;
1715 		vdev_reopen(vd->vdev_top);
1716 		if (vdev_is_dead(vd->vdev_top)) {
1717 			vd->vdev_offline = B_FALSE;
1718 			vdev_reopen(vd->vdev_top);
1719 			return (spa_vdev_exit(spa, NULL, txg, EBUSY));
1720 		}
1721 	}
1722 
1723 	vd->vdev_tmpoffline = (flags & ZFS_OFFLINE_TEMPORARY) ?
1724 	    B_TRUE : B_FALSE;
1725 
1726 	vdev_config_dirty(vd->vdev_top);
1727 
1728 	return (spa_vdev_exit(spa, NULL, txg, 0));
1729 }
1730 
1731 /*
1732  * Clear the error counts associated with this vdev.  Unlike vdev_online() and
1733  * vdev_offline(), we assume the spa config is locked.  We also clear all
1734  * children.  If 'vd' is NULL, then the user wants to clear all vdevs.
1735  * If reopen is specified then attempt to reopen the vdev if the vdev is
1736  * faulted or degraded.
1737  */
1738 void
1739 vdev_clear(spa_t *spa, vdev_t *vd, boolean_t reopen_wanted)
1740 {
1741 	int c;
1742 
1743 	if (vd == NULL)
1744 		vd = spa->spa_root_vdev;
1745 
1746 	vd->vdev_stat.vs_read_errors = 0;
1747 	vd->vdev_stat.vs_write_errors = 0;
1748 	vd->vdev_stat.vs_checksum_errors = 0;
1749 	vd->vdev_is_failing = B_FALSE;
1750 
1751 	for (c = 0; c < vd->vdev_children; c++)
1752 		vdev_clear(spa, vd->vdev_child[c], reopen_wanted);
1753 
1754 	/*
1755 	 * If we're in the FAULTED state, then clear the persistent state and
1756 	 * attempt to reopen the device.  We also mark the vdev config dirty, so
1757 	 * that the new faulted state is written out to disk.
1758 	 */
1759 	if (reopen_wanted && (vd->vdev_faulted || vd->vdev_degraded)) {
1760 		vd->vdev_faulted = vd->vdev_degraded = 0;
1761 		vdev_reopen(vd);
1762 		vdev_config_dirty(vd->vdev_top);
1763 
1764 		if (vd->vdev_faulted)
1765 			spa_async_request(spa, SPA_ASYNC_RESILVER);
1766 
1767 		spa_event_notify(spa, vd, ESC_ZFS_VDEV_CLEAR);
1768 	}
1769 }
1770 
1771 int
1772 vdev_readable(vdev_t *vd)
1773 {
1774 	/* XXPOLICY */
1775 	return (!vdev_is_dead(vd));
1776 }
1777 
1778 int
1779 vdev_writeable(vdev_t *vd)
1780 {
1781 	return (!vdev_is_dead(vd) && !vd->vdev_is_failing);
1782 }
1783 
1784 int
1785 vdev_is_dead(vdev_t *vd)
1786 {
1787 	return (vd->vdev_state < VDEV_STATE_DEGRADED);
1788 }
1789 
1790 int
1791 vdev_error_inject(vdev_t *vd, zio_t *zio)
1792 {
1793 	int error = 0;
1794 
1795 	if (vd->vdev_fault_mode == VDEV_FAULT_NONE)
1796 		return (0);
1797 
1798 	if (((1ULL << zio->io_type) & vd->vdev_fault_mask) == 0)
1799 		return (0);
1800 
1801 	switch (vd->vdev_fault_mode) {
1802 	case VDEV_FAULT_RANDOM:
1803 		if (spa_get_random(vd->vdev_fault_arg) == 0)
1804 			error = EIO;
1805 		break;
1806 
1807 	case VDEV_FAULT_COUNT:
1808 		if ((int64_t)--vd->vdev_fault_arg <= 0)
1809 			vd->vdev_fault_mode = VDEV_FAULT_NONE;
1810 		error = EIO;
1811 		break;
1812 	}
1813 
1814 	return (error);
1815 }
1816 
1817 /*
1818  * Get statistics for the given vdev.
1819  */
1820 void
1821 vdev_get_stats(vdev_t *vd, vdev_stat_t *vs)
1822 {
1823 	vdev_t *rvd = vd->vdev_spa->spa_root_vdev;
1824 	int c, t;
1825 
1826 	mutex_enter(&vd->vdev_stat_lock);
1827 	bcopy(&vd->vdev_stat, vs, sizeof (*vs));
1828 	vs->vs_timestamp = gethrtime() - vs->vs_timestamp;
1829 	vs->vs_state = vd->vdev_state;
1830 	vs->vs_rsize = vdev_get_rsize(vd);
1831 	mutex_exit(&vd->vdev_stat_lock);
1832 
1833 	/*
1834 	 * If we're getting stats on the root vdev, aggregate the I/O counts
1835 	 * over all top-level vdevs (i.e. the direct children of the root).
1836 	 */
1837 	if (vd == rvd) {
1838 		for (c = 0; c < rvd->vdev_children; c++) {
1839 			vdev_t *cvd = rvd->vdev_child[c];
1840 			vdev_stat_t *cvs = &cvd->vdev_stat;
1841 
1842 			mutex_enter(&vd->vdev_stat_lock);
1843 			for (t = 0; t < ZIO_TYPES; t++) {
1844 				vs->vs_ops[t] += cvs->vs_ops[t];
1845 				vs->vs_bytes[t] += cvs->vs_bytes[t];
1846 			}
1847 			vs->vs_read_errors += cvs->vs_read_errors;
1848 			vs->vs_write_errors += cvs->vs_write_errors;
1849 			vs->vs_checksum_errors += cvs->vs_checksum_errors;
1850 			vs->vs_scrub_examined += cvs->vs_scrub_examined;
1851 			vs->vs_scrub_errors += cvs->vs_scrub_errors;
1852 			mutex_exit(&vd->vdev_stat_lock);
1853 		}
1854 	}
1855 }
1856 
1857 void
1858 vdev_stat_update(zio_t *zio)
1859 {
1860 	vdev_t *vd = zio->io_vd;
1861 	vdev_t *pvd;
1862 	uint64_t txg = zio->io_txg;
1863 	vdev_stat_t *vs = &vd->vdev_stat;
1864 	zio_type_t type = zio->io_type;
1865 	int flags = zio->io_flags;
1866 
1867 	if (zio->io_error == 0) {
1868 		if (!(flags & ZIO_FLAG_IO_BYPASS)) {
1869 			mutex_enter(&vd->vdev_stat_lock);
1870 			vs->vs_ops[type]++;
1871 			vs->vs_bytes[type] += zio->io_size;
1872 			mutex_exit(&vd->vdev_stat_lock);
1873 		}
1874 		if ((flags & ZIO_FLAG_IO_REPAIR) &&
1875 		    zio->io_delegate_list == NULL) {
1876 			mutex_enter(&vd->vdev_stat_lock);
1877 			if (flags & ZIO_FLAG_SCRUB_THREAD)
1878 				vs->vs_scrub_repaired += zio->io_size;
1879 			else
1880 				vs->vs_self_healed += zio->io_size;
1881 			mutex_exit(&vd->vdev_stat_lock);
1882 		}
1883 		return;
1884 	}
1885 
1886 	if (flags & ZIO_FLAG_SPECULATIVE)
1887 		return;
1888 
1889 	if (vdev_readable(vd)) {
1890 		mutex_enter(&vd->vdev_stat_lock);
1891 		if (type == ZIO_TYPE_READ) {
1892 			if (zio->io_error == ECKSUM)
1893 				vs->vs_checksum_errors++;
1894 			else
1895 				vs->vs_read_errors++;
1896 		}
1897 		if (type == ZIO_TYPE_WRITE)
1898 			vs->vs_write_errors++;
1899 		mutex_exit(&vd->vdev_stat_lock);
1900 	}
1901 
1902 	if (type == ZIO_TYPE_WRITE) {
1903 		if (txg == 0 || vd->vdev_children != 0)
1904 			return;
1905 		if (flags & ZIO_FLAG_SCRUB_THREAD) {
1906 			ASSERT(flags & ZIO_FLAG_IO_REPAIR);
1907 			for (pvd = vd; pvd != NULL; pvd = pvd->vdev_parent)
1908 				vdev_dtl_dirty(&pvd->vdev_dtl_scrub, txg, 1);
1909 		}
1910 		if (!(flags & ZIO_FLAG_IO_REPAIR)) {
1911 			if (vdev_dtl_contains(&vd->vdev_dtl_map, txg, 1))
1912 				return;
1913 			vdev_dirty(vd->vdev_top, VDD_DTL, vd, txg);
1914 			for (pvd = vd; pvd != NULL; pvd = pvd->vdev_parent)
1915 				vdev_dtl_dirty(&pvd->vdev_dtl_map, txg, 1);
1916 		}
1917 	}
1918 }
1919 
1920 void
1921 vdev_scrub_stat_update(vdev_t *vd, pool_scrub_type_t type, boolean_t complete)
1922 {
1923 	int c;
1924 	vdev_stat_t *vs = &vd->vdev_stat;
1925 
1926 	for (c = 0; c < vd->vdev_children; c++)
1927 		vdev_scrub_stat_update(vd->vdev_child[c], type, complete);
1928 
1929 	mutex_enter(&vd->vdev_stat_lock);
1930 
1931 	if (type == POOL_SCRUB_NONE) {
1932 		/*
1933 		 * Update completion and end time.  Leave everything else alone
1934 		 * so we can report what happened during the previous scrub.
1935 		 */
1936 		vs->vs_scrub_complete = complete;
1937 		vs->vs_scrub_end = gethrestime_sec();
1938 	} else {
1939 		vs->vs_scrub_type = type;
1940 		vs->vs_scrub_complete = 0;
1941 		vs->vs_scrub_examined = 0;
1942 		vs->vs_scrub_repaired = 0;
1943 		vs->vs_scrub_errors = 0;
1944 		vs->vs_scrub_start = gethrestime_sec();
1945 		vs->vs_scrub_end = 0;
1946 	}
1947 
1948 	mutex_exit(&vd->vdev_stat_lock);
1949 }
1950 
1951 /*
1952  * Update the in-core space usage stats for this vdev and the root vdev.
1953  */
1954 void
1955 vdev_space_update(vdev_t *vd, int64_t space_delta, int64_t alloc_delta)
1956 {
1957 	int64_t dspace_delta = space_delta;
1958 	spa_t *spa = vd->vdev_spa;
1959 	vdev_t *rvd = spa->spa_root_vdev;
1960 
1961 	ASSERT(vd == vd->vdev_top);
1962 	ASSERT(rvd == vd->vdev_parent);
1963 	ASSERT(vd->vdev_ms_count != 0);
1964 
1965 	/*
1966 	 * Apply the inverse of the psize-to-asize (ie. RAID-Z) space-expansion
1967 	 * factor.  We must calculate this here and not at the root vdev
1968 	 * because the root vdev's psize-to-asize is simply the max of its
1969 	 * childrens', thus not accurate enough for us.
1970 	 */
1971 	ASSERT((dspace_delta & (SPA_MINBLOCKSIZE-1)) == 0);
1972 	dspace_delta = (dspace_delta >> SPA_MINBLOCKSHIFT) *
1973 	    vd->vdev_deflate_ratio;
1974 
1975 	mutex_enter(&vd->vdev_stat_lock);
1976 	vd->vdev_stat.vs_space += space_delta;
1977 	vd->vdev_stat.vs_alloc += alloc_delta;
1978 	vd->vdev_stat.vs_dspace += dspace_delta;
1979 	mutex_exit(&vd->vdev_stat_lock);
1980 
1981 	/*
1982 	 * Don't count non-normal (e.g. intent log) space as part of
1983 	 * the pool's capacity.
1984 	 */
1985 	if (vd->vdev_mg->mg_class != spa->spa_normal_class)
1986 		return;
1987 
1988 	mutex_enter(&rvd->vdev_stat_lock);
1989 	rvd->vdev_stat.vs_space += space_delta;
1990 	rvd->vdev_stat.vs_alloc += alloc_delta;
1991 	rvd->vdev_stat.vs_dspace += dspace_delta;
1992 	mutex_exit(&rvd->vdev_stat_lock);
1993 }
1994 
1995 /*
1996  * Mark a top-level vdev's config as dirty, placing it on the dirty list
1997  * so that it will be written out next time the vdev configuration is synced.
1998  * If the root vdev is specified (vdev_top == NULL), dirty all top-level vdevs.
1999  */
2000 void
2001 vdev_config_dirty(vdev_t *vd)
2002 {
2003 	spa_t *spa = vd->vdev_spa;
2004 	vdev_t *rvd = spa->spa_root_vdev;
2005 	int c;
2006 
2007 	/*
2008 	 * The dirty list is protected by the config lock.  The caller must
2009 	 * either hold the config lock as writer, or must be the sync thread
2010 	 * (which holds the lock as reader).  There's only one sync thread,
2011 	 * so this is sufficient to ensure mutual exclusion.
2012 	 */
2013 	ASSERT(spa_config_held(spa, RW_WRITER) ||
2014 	    dsl_pool_sync_context(spa_get_dsl(spa)));
2015 
2016 	if (vd == rvd) {
2017 		for (c = 0; c < rvd->vdev_children; c++)
2018 			vdev_config_dirty(rvd->vdev_child[c]);
2019 	} else {
2020 		ASSERT(vd == vd->vdev_top);
2021 
2022 		if (!list_link_active(&vd->vdev_dirty_node))
2023 			list_insert_head(&spa->spa_dirty_list, vd);
2024 	}
2025 }
2026 
2027 void
2028 vdev_config_clean(vdev_t *vd)
2029 {
2030 	spa_t *spa = vd->vdev_spa;
2031 
2032 	ASSERT(spa_config_held(spa, RW_WRITER) ||
2033 	    dsl_pool_sync_context(spa_get_dsl(spa)));
2034 
2035 	ASSERT(list_link_active(&vd->vdev_dirty_node));
2036 	list_remove(&spa->spa_dirty_list, vd);
2037 }
2038 
2039 void
2040 vdev_propagate_state(vdev_t *vd)
2041 {
2042 	vdev_t *rvd = vd->vdev_spa->spa_root_vdev;
2043 	int degraded = 0, faulted = 0;
2044 	int corrupted = 0;
2045 	int c;
2046 	vdev_t *child;
2047 
2048 	if (vd->vdev_children > 0) {
2049 		for (c = 0; c < vd->vdev_children; c++) {
2050 			child = vd->vdev_child[c];
2051 			if (vdev_is_dead(child) && !vdev_readable(child))
2052 				faulted++;
2053 			else if (child->vdev_state <= VDEV_STATE_DEGRADED)
2054 				degraded++;
2055 
2056 			if (child->vdev_stat.vs_aux == VDEV_AUX_CORRUPT_DATA)
2057 				corrupted++;
2058 		}
2059 
2060 		vd->vdev_ops->vdev_op_state_change(vd, faulted, degraded);
2061 
2062 		/*
2063 		 * Root special: if there is a toplevel vdev that cannot be
2064 		 * opened due to corrupted metadata, then propagate the root
2065 		 * vdev's aux state as 'corrupt' rather than 'insufficient
2066 		 * replicas'.
2067 		 */
2068 		if (corrupted && vd == rvd &&
2069 		    rvd->vdev_state == VDEV_STATE_CANT_OPEN)
2070 			vdev_set_state(rvd, B_FALSE, VDEV_STATE_CANT_OPEN,
2071 			    VDEV_AUX_CORRUPT_DATA);
2072 	}
2073 
2074 	if (vd->vdev_parent && !vd->vdev_islog)
2075 		vdev_propagate_state(vd->vdev_parent);
2076 }
2077 
2078 /*
2079  * Set a vdev's state.  If this is during an open, we don't update the parent
2080  * state, because we're in the process of opening children depth-first.
2081  * Otherwise, we propagate the change to the parent.
2082  *
2083  * If this routine places a device in a faulted state, an appropriate ereport is
2084  * generated.
2085  */
2086 void
2087 vdev_set_state(vdev_t *vd, boolean_t isopen, vdev_state_t state, vdev_aux_t aux)
2088 {
2089 	uint64_t save_state;
2090 
2091 	if (state == vd->vdev_state) {
2092 		vd->vdev_stat.vs_aux = aux;
2093 		return;
2094 	}
2095 
2096 	save_state = vd->vdev_state;
2097 
2098 	vd->vdev_state = state;
2099 	vd->vdev_stat.vs_aux = aux;
2100 
2101 	/*
2102 	 * If we are setting the vdev state to anything but an open state, then
2103 	 * always close the underlying device.  Otherwise, we keep accessible
2104 	 * but invalid devices open forever.  We don't call vdev_close() itself,
2105 	 * because that implies some extra checks (offline, etc) that we don't
2106 	 * want here.  This is limited to leaf devices, because otherwise
2107 	 * closing the device will affect other children.
2108 	 */
2109 	if (!vdev_readable(vd) && vd->vdev_ops->vdev_op_leaf)
2110 		vd->vdev_ops->vdev_op_close(vd);
2111 
2112 	if (vd->vdev_removed &&
2113 	    state == VDEV_STATE_CANT_OPEN &&
2114 	    (aux == VDEV_AUX_OPEN_FAILED || vd->vdev_checkremove)) {
2115 		/*
2116 		 * If the previous state is set to VDEV_STATE_REMOVED, then this
2117 		 * device was previously marked removed and someone attempted to
2118 		 * reopen it.  If this failed due to a nonexistent device, then
2119 		 * keep the device in the REMOVED state.  We also let this be if
2120 		 * it is one of our special test online cases, which is only
2121 		 * attempting to online the device and shouldn't generate an FMA
2122 		 * fault.
2123 		 */
2124 		vd->vdev_state = VDEV_STATE_REMOVED;
2125 		vd->vdev_stat.vs_aux = VDEV_AUX_NONE;
2126 	} else if (state == VDEV_STATE_REMOVED) {
2127 		/*
2128 		 * Indicate to the ZFS DE that this device has been removed, and
2129 		 * any recent errors should be ignored.
2130 		 */
2131 		zfs_post_remove(vd->vdev_spa, vd);
2132 		vd->vdev_removed = B_TRUE;
2133 	} else if (state == VDEV_STATE_CANT_OPEN) {
2134 		/*
2135 		 * If we fail to open a vdev during an import, we mark it as
2136 		 * "not available", which signifies that it was never there to
2137 		 * begin with.  Failure to open such a device is not considered
2138 		 * an error.
2139 		 */
2140 		if (vd->vdev_spa->spa_load_state == SPA_LOAD_IMPORT &&
2141 		    vd->vdev_ops->vdev_op_leaf)
2142 			vd->vdev_not_present = 1;
2143 
2144 		/*
2145 		 * Post the appropriate ereport.  If the 'prevstate' field is
2146 		 * set to something other than VDEV_STATE_UNKNOWN, it indicates
2147 		 * that this is part of a vdev_reopen().  In this case, we don't
2148 		 * want to post the ereport if the device was already in the
2149 		 * CANT_OPEN state beforehand.
2150 		 *
2151 		 * If the 'checkremove' flag is set, then this is an attempt to
2152 		 * online the device in response to an insertion event.  If we
2153 		 * hit this case, then we have detected an insertion event for a
2154 		 * faulted or offline device that wasn't in the removed state.
2155 		 * In this scenario, we don't post an ereport because we are
2156 		 * about to replace the device, or attempt an online with
2157 		 * vdev_forcefault, which will generate the fault for us.
2158 		 */
2159 		if ((vd->vdev_prevstate != state || vd->vdev_forcefault) &&
2160 		    !vd->vdev_not_present && !vd->vdev_checkremove &&
2161 		    vd != vd->vdev_spa->spa_root_vdev) {
2162 			const char *class;
2163 
2164 			switch (aux) {
2165 			case VDEV_AUX_OPEN_FAILED:
2166 				class = FM_EREPORT_ZFS_DEVICE_OPEN_FAILED;
2167 				break;
2168 			case VDEV_AUX_CORRUPT_DATA:
2169 				class = FM_EREPORT_ZFS_DEVICE_CORRUPT_DATA;
2170 				break;
2171 			case VDEV_AUX_NO_REPLICAS:
2172 				class = FM_EREPORT_ZFS_DEVICE_NO_REPLICAS;
2173 				break;
2174 			case VDEV_AUX_BAD_GUID_SUM:
2175 				class = FM_EREPORT_ZFS_DEVICE_BAD_GUID_SUM;
2176 				break;
2177 			case VDEV_AUX_TOO_SMALL:
2178 				class = FM_EREPORT_ZFS_DEVICE_TOO_SMALL;
2179 				break;
2180 			case VDEV_AUX_BAD_LABEL:
2181 				class = FM_EREPORT_ZFS_DEVICE_BAD_LABEL;
2182 				break;
2183 			default:
2184 				class = FM_EREPORT_ZFS_DEVICE_UNKNOWN;
2185 			}
2186 
2187 			zfs_ereport_post(class, vd->vdev_spa,
2188 			    vd, NULL, save_state, 0);
2189 		}
2190 
2191 		/* Erase any notion of persistent removed state */
2192 		vd->vdev_removed = B_FALSE;
2193 	} else {
2194 		vd->vdev_removed = B_FALSE;
2195 	}
2196 
2197 	if (!isopen)
2198 		vdev_propagate_state(vd);
2199 }
2200