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 * Copyright (c) 2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
23 * All rights reserved.
24 *
25 * Portions Copyright (c) 2012 Martin Matuska <mm@FreeBSD.org>
26 */
27
28#include <sys/zfs_context.h>
29#include <sys/param.h>
30#include <sys/kernel.h>
31#include <sys/bio.h>
32#include <sys/disk.h>
33#include <sys/spa.h>
34#include <sys/spa_impl.h>
35#include <sys/vdev_impl.h>
36#include <sys/fs/zfs.h>
37#include <sys/zio.h>
38#include <geom/geom.h>
39#include <geom/geom_int.h>
40
41/*
42 * Virtual device vector for GEOM.
43 */
44
45struct g_class zfs_vdev_class = {
46 .name = "ZFS::VDEV",
47 .version = G_VERSION,
48};
49
50DECLARE_GEOM_CLASS(zfs_vdev_class, zfs_vdev);
51
52/*
53 * Don't send BIO_FLUSH.
54 */
55static int vdev_geom_bio_flush_disable = 0;
56TUNABLE_INT("vfs.zfs.vdev.bio_flush_disable", &vdev_geom_bio_flush_disable);
57SYSCTL_DECL(_vfs_zfs_vdev);
58SYSCTL_INT(_vfs_zfs_vdev, OID_AUTO, bio_flush_disable, CTLFLAG_RW,
59 &vdev_geom_bio_flush_disable, 0, "Disable BIO_FLUSH");
60
61static void
62vdev_geom_orphan(struct g_consumer *cp)
63{
64 vdev_t *vd;
65
66 g_topology_assert();
67
68 vd = cp->private;
69
70 /*
71 * Orphan callbacks occur from the GEOM event thread.
72 * Concurrent with this call, new I/O requests may be
73 * working their way through GEOM about to find out
74 * (only once executed by the g_down thread) that we've
75 * been orphaned from our disk provider. These I/Os
76 * must be retired before we can detach our consumer.
77 * This is most easily achieved by acquiring the
78 * SPA ZIO configuration lock as a writer, but doing
79 * so with the GEOM topology lock held would cause
80 * a lock order reversal. Instead, rely on the SPA's
81 * async removal support to invoke a close on this
82 * vdev once it is safe to do so.
83 */
84 zfs_post_remove(vd->vdev_spa, vd);
85 vd->vdev_remove_wanted = B_TRUE;
86 spa_async_request(vd->vdev_spa, SPA_ASYNC_REMOVE);
87}
88
89static struct g_consumer *
90vdev_geom_attach(struct g_provider *pp)
91{
92 struct g_geom *gp;
93 struct g_consumer *cp;
94
95 g_topology_assert();
96
97 ZFS_LOG(1, "Attaching to %s.", pp->name);
98 /* Do we have geom already? No? Create one. */
99 LIST_FOREACH(gp, &zfs_vdev_class.geom, geom) {
100 if (gp->flags & G_GEOM_WITHER)
101 continue;
102 if (strcmp(gp->name, "zfs::vdev") != 0)
103 continue;
104 break;
105 }
106 if (gp == NULL) {
107 gp = g_new_geomf(&zfs_vdev_class, "zfs::vdev");
108 gp->orphan = vdev_geom_orphan;
109 cp = g_new_consumer(gp);
110 if (g_attach(cp, pp) != 0) {
111 g_wither_geom(gp, ENXIO);
112 return (NULL);
113 }
114 if (g_access(cp, 1, 0, 1) != 0) {
115 g_wither_geom(gp, ENXIO);
116 return (NULL);
117 }
118 ZFS_LOG(1, "Created geom and consumer for %s.", pp->name);
119 } else {
120 /* Check if we are already connected to this provider. */
121 LIST_FOREACH(cp, &gp->consumer, consumer) {
122 if (cp->provider == pp) {
123 ZFS_LOG(1, "Found consumer for %s.", pp->name);
124 break;
125 }
126 }
127 if (cp == NULL) {
128 cp = g_new_consumer(gp);
129 if (g_attach(cp, pp) != 0) {
130 g_destroy_consumer(cp);
131 return (NULL);
132 }
133 if (g_access(cp, 1, 0, 1) != 0) {
134 g_detach(cp);
135 g_destroy_consumer(cp);
136 return (NULL);
137 }
138 ZFS_LOG(1, "Created consumer for %s.", pp->name);
139 } else {
140 if (g_access(cp, 1, 0, 1) != 0)
141 return (NULL);
142 ZFS_LOG(1, "Used existing consumer for %s.", pp->name);
143 }
144 }
145 return (cp);
146}
147
148static void
149vdev_geom_detach(void *arg, int flag __unused)
150{
151 struct g_geom *gp;
152 struct g_consumer *cp;
153
154 g_topology_assert();
155 cp = arg;
156 gp = cp->geom;
157
158 ZFS_LOG(1, "Closing access to %s.", cp->provider->name);
159 g_access(cp, -1, 0, -1);
160 /* Destroy consumer on last close. */
161 if (cp->acr == 0 && cp->ace == 0) {
162 ZFS_LOG(1, "Destroyed consumer to %s.", cp->provider->name);
163 if (cp->acw > 0)
164 g_access(cp, 0, -cp->acw, 0);
165 g_detach(cp);
166 g_destroy_consumer(cp);
167 }
168 /* Destroy geom if there are no consumers left. */
169 if (LIST_EMPTY(&gp->consumer)) {
170 ZFS_LOG(1, "Destroyed geom %s.", gp->name);
171 g_wither_geom(gp, ENXIO);
172 }
173}
174
175static uint64_t
176nvlist_get_guid(nvlist_t *list)
177{
178 nvpair_t *elem = NULL;
179 uint64_t value;
180
181 while ((elem = nvlist_next_nvpair(list, elem)) != NULL) {
182 if (nvpair_type(elem) == DATA_TYPE_UINT64 &&
183 strcmp(nvpair_name(elem), "guid") == 0) {
184 VERIFY(nvpair_value_uint64(elem, &value) == 0);
185 return (value);
186 }
187 }
188 return (0);
189}
190
191static int
192vdev_geom_io(struct g_consumer *cp, int cmd, void *data, off_t offset, off_t size)
193{
194 struct bio *bp;
195 u_char *p;
196 off_t off, maxio;
197 int error;
198
199 ASSERT((offset % cp->provider->sectorsize) == 0);
200 ASSERT((size % cp->provider->sectorsize) == 0);
201
202 bp = g_alloc_bio();
203 off = offset;
204 offset += size;
205 p = data;
206 maxio = MAXPHYS - (MAXPHYS % cp->provider->sectorsize);
207 error = 0;
208
209 for (; off < offset; off += maxio, p += maxio, size -= maxio) {
210 bzero(bp, sizeof(*bp));
211 bp->bio_cmd = cmd;
212 bp->bio_done = NULL;
213 bp->bio_offset = off;
214 bp->bio_length = MIN(size, maxio);
215 bp->bio_data = p;
216 g_io_request(bp, cp);
217 error = biowait(bp, "vdev_geom_io");
218 if (error != 0)
219 break;
220 }
221
222 g_destroy_bio(bp);
223 return (error);
224}
225
226static uint64_t
227vdev_geom_read_guid(struct g_consumer *cp)
228{
229 struct g_provider *pp;
230 vdev_label_t *label;
231 char *p, *buf;
232 size_t buflen;
233 uint64_t psize;
234 off_t offset, size;
235 uint64_t guid;
236 int error, l, len;
237
238 g_topology_assert_not();
239
240 pp = cp->provider;
241 ZFS_LOG(1, "Reading guid from %s...", pp->name);
242
243 psize = pp->mediasize;
244 psize = P2ALIGN(psize, (uint64_t)sizeof(vdev_label_t));
245
246 size = sizeof(*label) + pp->sectorsize -
247 ((sizeof(*label) - 1) % pp->sectorsize) - 1;
248
249 guid = 0;
250 label = kmem_alloc(size, KM_SLEEP);
251 buflen = sizeof(label->vl_vdev_phys.vp_nvlist);
252
253 for (l = 0; l < VDEV_LABELS; l++) {
254 nvlist_t *config = NULL;
255
256 offset = vdev_label_offset(psize, l, 0);
257 if ((offset % pp->sectorsize) != 0)
258 continue;
259
260 if (vdev_geom_io(cp, BIO_READ, label, offset, size) != 0)
261 continue;
262 buf = label->vl_vdev_phys.vp_nvlist;
263
264 if (nvlist_unpack(buf, buflen, &config, 0) != 0)
265 continue;
266
267 guid = nvlist_get_guid(config);
268 nvlist_free(config);
269 if (guid != 0)
270 break;
271 }
272
273 kmem_free(label, size);
274 if (guid != 0)
275 ZFS_LOG(1, "guid for %s is %ju", pp->name, (uintmax_t)guid);
276 return (guid);
277}
278
279static void
280vdev_geom_taste_orphan(struct g_consumer *cp)
281{
282
283 KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
284 cp->provider->name));
285}
286
287static struct g_consumer *
288vdev_geom_attach_by_guid(uint64_t guid)
289{
290 struct g_class *mp;
291 struct g_geom *gp, *zgp;
292 struct g_provider *pp;
293 struct g_consumer *cp, *zcp;
294 uint64_t pguid;
295
296 g_topology_assert();
297
298 zgp = g_new_geomf(&zfs_vdev_class, "zfs::vdev::taste");
299 /* This orphan function should be never called. */
300 zgp->orphan = vdev_geom_taste_orphan;
301 zcp = g_new_consumer(zgp);
302
303 cp = NULL;
304 LIST_FOREACH(mp, &g_classes, class) {
305 if (mp == &zfs_vdev_class)
306 continue;
307 LIST_FOREACH(gp, &mp->geom, geom) {
308 if (gp->flags & G_GEOM_WITHER)
309 continue;
310 LIST_FOREACH(pp, &gp->provider, provider) {
311 if (pp->flags & G_PF_WITHER)
312 continue;
313 g_attach(zcp, pp);
314 if (g_access(zcp, 1, 0, 0) != 0) {
315 g_detach(zcp);
316 continue;
317 }
318 g_topology_unlock();
319 pguid = vdev_geom_read_guid(zcp);
320 g_topology_lock();
321 g_access(zcp, -1, 0, 0);
322 g_detach(zcp);
323 if (pguid != guid)
324 continue;
325 cp = vdev_geom_attach(pp);
326 if (cp == NULL) {
327 printf("ZFS WARNING: Unable to attach to %s.\n",
328 pp->name);
329 continue;
330 }
331 break;
332 }
333 if (cp != NULL)
334 break;
335 }
336 if (cp != NULL)
337 break;
338 }
339end:
340 g_destroy_consumer(zcp);
341 g_destroy_geom(zgp);
342 return (cp);
343}
344
345static struct g_consumer *
346vdev_geom_open_by_guid(vdev_t *vd)
347{
348 struct g_consumer *cp;
349 char *buf;
350 size_t len;
351
352 g_topology_assert();
353
354 ZFS_LOG(1, "Searching by guid [%ju].", (uintmax_t)vd->vdev_guid);
355 cp = vdev_geom_attach_by_guid(vd->vdev_guid);
356 if (cp != NULL) {
357 len = strlen(cp->provider->name) + strlen("/dev/") + 1;
358 buf = kmem_alloc(len, KM_SLEEP);
359
360 snprintf(buf, len, "/dev/%s", cp->provider->name);
361 spa_strfree(vd->vdev_path);
362 vd->vdev_path = buf;
363
364 ZFS_LOG(1, "Attach by guid [%ju] succeeded, provider %s.",
365 (uintmax_t)vd->vdev_guid, vd->vdev_path);
366 } else {
367 ZFS_LOG(1, "Search by guid [%ju] failed.",
368 (uintmax_t)vd->vdev_guid);
369 }
370
371 return (cp);
372}
373
374static struct g_consumer *
375vdev_geom_open_by_path(vdev_t *vd, int check_guid)
376{
377 struct g_provider *pp;
378 struct g_consumer *cp;
379 uint64_t guid;
380
381 g_topology_assert();
382
383 cp = NULL;
384 pp = g_provider_by_name(vd->vdev_path + sizeof("/dev/") - 1);
385 if (pp != NULL) {
386 ZFS_LOG(1, "Found provider by name %s.", vd->vdev_path);
387 cp = vdev_geom_attach(pp);
388 if (cp != NULL && check_guid && ISP2(pp->sectorsize) &&
389 pp->sectorsize <= VDEV_PAD_SIZE) {
390 g_topology_unlock();
391 guid = vdev_geom_read_guid(cp);
392 g_topology_lock();
393 if (guid != vd->vdev_guid) {
394 vdev_geom_detach(cp, 0);
395 cp = NULL;
396 ZFS_LOG(1, "guid mismatch for provider %s: "
397 "%ju != %ju.", vd->vdev_path,
398 (uintmax_t)vd->vdev_guid, (uintmax_t)guid);
399 } else {
400 ZFS_LOG(1, "guid match for provider %s.",
401 vd->vdev_path);
402 }
403 }
404 }
405
406 return (cp);
407}
408
409static int
410vdev_geom_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize,
411 uint64_t *ashift)
412{
413 struct g_provider *pp;
414 struct g_consumer *cp;
415 size_t bufsize;
416 int error;
417
418 /*
419 * We must have a pathname, and it must be absolute.
420 */
421 if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') {
422 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
423 return (EINVAL);
424 }
425
426 vd->vdev_tsd = NULL;
427
428 DROP_GIANT();
429 g_topology_lock();
430 error = 0;
431
432 /*
433 * If we're creating or splitting a pool, just find the GEOM provider
434 * by its name and ignore GUID mismatches.
435 */
436 if (vd->vdev_spa->spa_load_state == SPA_LOAD_NONE ||
437 vd->vdev_spa->spa_splitting_newspa == B_TRUE)
438 cp = vdev_geom_open_by_path(vd, 0);
439 else {
440 cp = vdev_geom_open_by_path(vd, 1);
441 if (cp == NULL) {
442 /*
443 * The device at vd->vdev_path doesn't have the
444 * expected guid. The disks might have merely
445 * moved around so try all other GEOM providers
446 * to find one with the right guid.
447 */
448 cp = vdev_geom_open_by_guid(vd);
449 }
450 }
451
452 if (cp == NULL) {
453 ZFS_LOG(1, "Provider %s not found.", vd->vdev_path);
454 error = ENOENT;
455 } else if (cp->provider->sectorsize > VDEV_PAD_SIZE ||
456 !ISP2(cp->provider->sectorsize)) {
457 ZFS_LOG(1, "Provider %s has unsupported sectorsize.",
458 vd->vdev_path);
459 vdev_geom_detach(cp, 0);
460 error = EINVAL;
461 cp = NULL;
462 } else if (cp->acw == 0 && (spa_mode(vd->vdev_spa) & FWRITE) != 0) {
463 int i;
464
465 for (i = 0; i < 5; i++) {
466 error = g_access(cp, 0, 1, 0);
467 if (error == 0)
468 break;
469 g_topology_unlock();
470 tsleep(vd, 0, "vdev", hz / 2);
471 g_topology_lock();
472 }
473 if (error != 0) {
474 printf("ZFS WARNING: Unable to open %s for writing (error=%d).\n",
475 vd->vdev_path, error);
476 vdev_geom_detach(cp, 0);
477 cp = NULL;
478 }
479 }
480 g_topology_unlock();
481 PICKUP_GIANT();
482 if (cp == NULL) {
483 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
484 return (error);
485 }
486
487 cp->private = vd;
488 vd->vdev_tsd = cp;
489 pp = cp->provider;
490
491 /*
492 * Determine the actual size of the device.
493 */
494 *max_psize = *psize = pp->mediasize;
495
496 /*
497 * Determine the device's minimum transfer size.
498 */
499 *ashift = highbit(MAX(pp->sectorsize, SPA_MINBLOCKSIZE)) - 1;
500
501 /*
502 * Clear the nowritecache bit, so that on a vdev_reopen() we will
503 * try again.
504 */
505 vd->vdev_nowritecache = B_FALSE;
506
507 if (vd->vdev_physpath != NULL)
508 spa_strfree(vd->vdev_physpath);
509 bufsize = sizeof("/dev/") + strlen(pp->name);
510 vd->vdev_physpath = kmem_alloc(bufsize, KM_SLEEP);
511 snprintf(vd->vdev_physpath, bufsize, "/dev/%s", pp->name);
512
513 return (0);
514}
515
516static void
517vdev_geom_close(vdev_t *vd)
518{
519 struct g_consumer *cp;
520
521 cp = vd->vdev_tsd;
522 if (cp == NULL)
523 return;
524 vd->vdev_tsd = NULL;
525 vd->vdev_delayed_close = B_FALSE;
526 g_post_event(vdev_geom_detach, cp, M_WAITOK, NULL);
527}
528
529static void
530vdev_geom_io_intr(struct bio *bp)
531{
532 vdev_t *vd;
533 zio_t *zio;
534
535 zio = bp->bio_caller1;
536 vd = zio->io_vd;
537 zio->io_error = bp->bio_error;
538 if (zio->io_error == 0 && bp->bio_resid != 0)
539 zio->io_error = EIO;
540 if (bp->bio_cmd == BIO_FLUSH && bp->bio_error == ENOTSUP) {
541 /*
542 * If we get ENOTSUP, we know that no future
543 * attempts will ever succeed. In this case we
544 * set a persistent bit so that we don't bother
545 * with the ioctl in the future.
546 */
547 vd->vdev_nowritecache = B_TRUE;
548 }
549 if (zio->io_error == EIO && !vd->vdev_remove_wanted) {
550 /*
551 * If provider's error is set we assume it is being
552 * removed.
553 */
554 if (bp->bio_to->error != 0) {
555 /*
556 * We post the resource as soon as possible, instead of
557 * when the async removal actually happens, because the
558 * DE is using this information to discard previous I/O
559 * errors.
560 */
561 /* XXX: zfs_post_remove() can sleep. */
562 zfs_post_remove(zio->io_spa, vd);
563 vd->vdev_remove_wanted = B_TRUE;
564 spa_async_request(zio->io_spa, SPA_ASYNC_REMOVE);
565 } else if (!vd->vdev_delayed_close) {
566 vd->vdev_delayed_close = B_TRUE;
567 }
568 }
569 g_destroy_bio(bp);
570 zio_interrupt(zio);
571}
572
573static int
574vdev_geom_io_start(zio_t *zio)
575{
576 vdev_t *vd;
577 struct g_consumer *cp;
578 struct bio *bp;
579 int error;
580
581 vd = zio->io_vd;
582
583 if (zio->io_type == ZIO_TYPE_IOCTL) {
584 /* XXPOLICY */
585 if (!vdev_readable(vd)) {
586 zio->io_error = ENXIO;
587 return (ZIO_PIPELINE_CONTINUE);
588 }
589
590 switch (zio->io_cmd) {
591
592 case DKIOCFLUSHWRITECACHE:
593
594 if (zfs_nocacheflush || vdev_geom_bio_flush_disable)
595 break;
596
597 if (vd->vdev_nowritecache) {
598 zio->io_error = ENOTSUP;
599 break;
600 }
601
602 goto sendreq;
603 default:
604 zio->io_error = ENOTSUP;
605 }
606
607 return (ZIO_PIPELINE_CONTINUE);
608 }
609sendreq:
610 cp = vd->vdev_tsd;
611 if (cp == NULL) {
612 zio->io_error = ENXIO;
613 return (ZIO_PIPELINE_CONTINUE);
614 }
615 bp = g_alloc_bio();
616 bp->bio_caller1 = zio;
617 switch (zio->io_type) {
618 case ZIO_TYPE_READ:
619 case ZIO_TYPE_WRITE:
620 bp->bio_cmd = zio->io_type == ZIO_TYPE_READ ? BIO_READ : BIO_WRITE;
621 bp->bio_data = zio->io_data;
622 bp->bio_offset = zio->io_offset;
623 bp->bio_length = zio->io_size;
624 break;
625 case ZIO_TYPE_IOCTL:
626 bp->bio_cmd = BIO_FLUSH;
627 bp->bio_flags |= BIO_ORDERED;
628 bp->bio_data = NULL;
629 bp->bio_offset = cp->provider->mediasize;
630 bp->bio_length = 0;
631 break;
632 }
633 bp->bio_done = vdev_geom_io_intr;
634
635 g_io_request(bp, cp);
636
637 return (ZIO_PIPELINE_STOP);
638}
639
640static void
641vdev_geom_io_done(zio_t *zio)
642{
643}
644
645static void
646vdev_geom_hold(vdev_t *vd)
647{
648}
649
650static void
651vdev_geom_rele(vdev_t *vd)
652{
653}
654
655vdev_ops_t vdev_geom_ops = {
656 vdev_geom_open,
657 vdev_geom_close,
658 vdev_default_asize,
659 vdev_geom_io_start,
660 vdev_geom_io_done,
661 NULL,
662 vdev_geom_hold,
663 vdev_geom_rele,
664 VDEV_TYPE_DISK, /* name of this vdev type */
665 B_TRUE /* leaf vdev */
666};
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 * Copyright (c) 2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
23 * All rights reserved.
24 *
25 * Portions Copyright (c) 2012 Martin Matuska <mm@FreeBSD.org>
26 */
27
28#include <sys/zfs_context.h>
29#include <sys/param.h>
30#include <sys/kernel.h>
31#include <sys/bio.h>
32#include <sys/disk.h>
33#include <sys/spa.h>
34#include <sys/spa_impl.h>
35#include <sys/vdev_impl.h>
36#include <sys/fs/zfs.h>
37#include <sys/zio.h>
38#include <geom/geom.h>
39#include <geom/geom_int.h>
40
41/*
42 * Virtual device vector for GEOM.
43 */
44
45struct g_class zfs_vdev_class = {
46 .name = "ZFS::VDEV",
47 .version = G_VERSION,
48};
49
50DECLARE_GEOM_CLASS(zfs_vdev_class, zfs_vdev);
51
52/*
53 * Don't send BIO_FLUSH.
54 */
55static int vdev_geom_bio_flush_disable = 0;
56TUNABLE_INT("vfs.zfs.vdev.bio_flush_disable", &vdev_geom_bio_flush_disable);
57SYSCTL_DECL(_vfs_zfs_vdev);
58SYSCTL_INT(_vfs_zfs_vdev, OID_AUTO, bio_flush_disable, CTLFLAG_RW,
59 &vdev_geom_bio_flush_disable, 0, "Disable BIO_FLUSH");
60
61static void
62vdev_geom_orphan(struct g_consumer *cp)
63{
64 vdev_t *vd;
65
66 g_topology_assert();
67
68 vd = cp->private;
69
70 /*
71 * Orphan callbacks occur from the GEOM event thread.
72 * Concurrent with this call, new I/O requests may be
73 * working their way through GEOM about to find out
74 * (only once executed by the g_down thread) that we've
75 * been orphaned from our disk provider. These I/Os
76 * must be retired before we can detach our consumer.
77 * This is most easily achieved by acquiring the
78 * SPA ZIO configuration lock as a writer, but doing
79 * so with the GEOM topology lock held would cause
80 * a lock order reversal. Instead, rely on the SPA's
81 * async removal support to invoke a close on this
82 * vdev once it is safe to do so.
83 */
84 zfs_post_remove(vd->vdev_spa, vd);
85 vd->vdev_remove_wanted = B_TRUE;
86 spa_async_request(vd->vdev_spa, SPA_ASYNC_REMOVE);
87}
88
89static struct g_consumer *
90vdev_geom_attach(struct g_provider *pp)
91{
92 struct g_geom *gp;
93 struct g_consumer *cp;
94
95 g_topology_assert();
96
97 ZFS_LOG(1, "Attaching to %s.", pp->name);
98 /* Do we have geom already? No? Create one. */
99 LIST_FOREACH(gp, &zfs_vdev_class.geom, geom) {
100 if (gp->flags & G_GEOM_WITHER)
101 continue;
102 if (strcmp(gp->name, "zfs::vdev") != 0)
103 continue;
104 break;
105 }
106 if (gp == NULL) {
107 gp = g_new_geomf(&zfs_vdev_class, "zfs::vdev");
108 gp->orphan = vdev_geom_orphan;
109 cp = g_new_consumer(gp);
110 if (g_attach(cp, pp) != 0) {
111 g_wither_geom(gp, ENXIO);
112 return (NULL);
113 }
114 if (g_access(cp, 1, 0, 1) != 0) {
115 g_wither_geom(gp, ENXIO);
116 return (NULL);
117 }
118 ZFS_LOG(1, "Created geom and consumer for %s.", pp->name);
119 } else {
120 /* Check if we are already connected to this provider. */
121 LIST_FOREACH(cp, &gp->consumer, consumer) {
122 if (cp->provider == pp) {
123 ZFS_LOG(1, "Found consumer for %s.", pp->name);
124 break;
125 }
126 }
127 if (cp == NULL) {
128 cp = g_new_consumer(gp);
129 if (g_attach(cp, pp) != 0) {
130 g_destroy_consumer(cp);
131 return (NULL);
132 }
133 if (g_access(cp, 1, 0, 1) != 0) {
134 g_detach(cp);
135 g_destroy_consumer(cp);
136 return (NULL);
137 }
138 ZFS_LOG(1, "Created consumer for %s.", pp->name);
139 } else {
140 if (g_access(cp, 1, 0, 1) != 0)
141 return (NULL);
142 ZFS_LOG(1, "Used existing consumer for %s.", pp->name);
143 }
144 }
145 return (cp);
146}
147
148static void
149vdev_geom_detach(void *arg, int flag __unused)
150{
151 struct g_geom *gp;
152 struct g_consumer *cp;
153
154 g_topology_assert();
155 cp = arg;
156 gp = cp->geom;
157
158 ZFS_LOG(1, "Closing access to %s.", cp->provider->name);
159 g_access(cp, -1, 0, -1);
160 /* Destroy consumer on last close. */
161 if (cp->acr == 0 && cp->ace == 0) {
162 ZFS_LOG(1, "Destroyed consumer to %s.", cp->provider->name);
163 if (cp->acw > 0)
164 g_access(cp, 0, -cp->acw, 0);
165 g_detach(cp);
166 g_destroy_consumer(cp);
167 }
168 /* Destroy geom if there are no consumers left. */
169 if (LIST_EMPTY(&gp->consumer)) {
170 ZFS_LOG(1, "Destroyed geom %s.", gp->name);
171 g_wither_geom(gp, ENXIO);
172 }
173}
174
175static uint64_t
176nvlist_get_guid(nvlist_t *list)
177{
178 nvpair_t *elem = NULL;
179 uint64_t value;
180
181 while ((elem = nvlist_next_nvpair(list, elem)) != NULL) {
182 if (nvpair_type(elem) == DATA_TYPE_UINT64 &&
183 strcmp(nvpair_name(elem), "guid") == 0) {
184 VERIFY(nvpair_value_uint64(elem, &value) == 0);
185 return (value);
186 }
187 }
188 return (0);
189}
190
191static int
192vdev_geom_io(struct g_consumer *cp, int cmd, void *data, off_t offset, off_t size)
193{
194 struct bio *bp;
195 u_char *p;
196 off_t off, maxio;
197 int error;
198
199 ASSERT((offset % cp->provider->sectorsize) == 0);
200 ASSERT((size % cp->provider->sectorsize) == 0);
201
202 bp = g_alloc_bio();
203 off = offset;
204 offset += size;
205 p = data;
206 maxio = MAXPHYS - (MAXPHYS % cp->provider->sectorsize);
207 error = 0;
208
209 for (; off < offset; off += maxio, p += maxio, size -= maxio) {
210 bzero(bp, sizeof(*bp));
211 bp->bio_cmd = cmd;
212 bp->bio_done = NULL;
213 bp->bio_offset = off;
214 bp->bio_length = MIN(size, maxio);
215 bp->bio_data = p;
216 g_io_request(bp, cp);
217 error = biowait(bp, "vdev_geom_io");
218 if (error != 0)
219 break;
220 }
221
222 g_destroy_bio(bp);
223 return (error);
224}
225
226static uint64_t
227vdev_geom_read_guid(struct g_consumer *cp)
228{
229 struct g_provider *pp;
230 vdev_label_t *label;
231 char *p, *buf;
232 size_t buflen;
233 uint64_t psize;
234 off_t offset, size;
235 uint64_t guid;
236 int error, l, len;
237
238 g_topology_assert_not();
239
240 pp = cp->provider;
241 ZFS_LOG(1, "Reading guid from %s...", pp->name);
242
243 psize = pp->mediasize;
244 psize = P2ALIGN(psize, (uint64_t)sizeof(vdev_label_t));
245
246 size = sizeof(*label) + pp->sectorsize -
247 ((sizeof(*label) - 1) % pp->sectorsize) - 1;
248
249 guid = 0;
250 label = kmem_alloc(size, KM_SLEEP);
251 buflen = sizeof(label->vl_vdev_phys.vp_nvlist);
252
253 for (l = 0; l < VDEV_LABELS; l++) {
254 nvlist_t *config = NULL;
255
256 offset = vdev_label_offset(psize, l, 0);
257 if ((offset % pp->sectorsize) != 0)
258 continue;
259
260 if (vdev_geom_io(cp, BIO_READ, label, offset, size) != 0)
261 continue;
262 buf = label->vl_vdev_phys.vp_nvlist;
263
264 if (nvlist_unpack(buf, buflen, &config, 0) != 0)
265 continue;
266
267 guid = nvlist_get_guid(config);
268 nvlist_free(config);
269 if (guid != 0)
270 break;
271 }
272
273 kmem_free(label, size);
274 if (guid != 0)
275 ZFS_LOG(1, "guid for %s is %ju", pp->name, (uintmax_t)guid);
276 return (guid);
277}
278
279static void
280vdev_geom_taste_orphan(struct g_consumer *cp)
281{
282
283 KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
284 cp->provider->name));
285}
286
287static struct g_consumer *
288vdev_geom_attach_by_guid(uint64_t guid)
289{
290 struct g_class *mp;
291 struct g_geom *gp, *zgp;
292 struct g_provider *pp;
293 struct g_consumer *cp, *zcp;
294 uint64_t pguid;
295
296 g_topology_assert();
297
298 zgp = g_new_geomf(&zfs_vdev_class, "zfs::vdev::taste");
299 /* This orphan function should be never called. */
300 zgp->orphan = vdev_geom_taste_orphan;
301 zcp = g_new_consumer(zgp);
302
303 cp = NULL;
304 LIST_FOREACH(mp, &g_classes, class) {
305 if (mp == &zfs_vdev_class)
306 continue;
307 LIST_FOREACH(gp, &mp->geom, geom) {
308 if (gp->flags & G_GEOM_WITHER)
309 continue;
310 LIST_FOREACH(pp, &gp->provider, provider) {
311 if (pp->flags & G_PF_WITHER)
312 continue;
313 g_attach(zcp, pp);
314 if (g_access(zcp, 1, 0, 0) != 0) {
315 g_detach(zcp);
316 continue;
317 }
318 g_topology_unlock();
319 pguid = vdev_geom_read_guid(zcp);
320 g_topology_lock();
321 g_access(zcp, -1, 0, 0);
322 g_detach(zcp);
323 if (pguid != guid)
324 continue;
325 cp = vdev_geom_attach(pp);
326 if (cp == NULL) {
327 printf("ZFS WARNING: Unable to attach to %s.\n",
328 pp->name);
329 continue;
330 }
331 break;
332 }
333 if (cp != NULL)
334 break;
335 }
336 if (cp != NULL)
337 break;
338 }
339end:
340 g_destroy_consumer(zcp);
341 g_destroy_geom(zgp);
342 return (cp);
343}
344
345static struct g_consumer *
346vdev_geom_open_by_guid(vdev_t *vd)
347{
348 struct g_consumer *cp;
349 char *buf;
350 size_t len;
351
352 g_topology_assert();
353
354 ZFS_LOG(1, "Searching by guid [%ju].", (uintmax_t)vd->vdev_guid);
355 cp = vdev_geom_attach_by_guid(vd->vdev_guid);
356 if (cp != NULL) {
357 len = strlen(cp->provider->name) + strlen("/dev/") + 1;
358 buf = kmem_alloc(len, KM_SLEEP);
359
360 snprintf(buf, len, "/dev/%s", cp->provider->name);
361 spa_strfree(vd->vdev_path);
362 vd->vdev_path = buf;
363
364 ZFS_LOG(1, "Attach by guid [%ju] succeeded, provider %s.",
365 (uintmax_t)vd->vdev_guid, vd->vdev_path);
366 } else {
367 ZFS_LOG(1, "Search by guid [%ju] failed.",
368 (uintmax_t)vd->vdev_guid);
369 }
370
371 return (cp);
372}
373
374static struct g_consumer *
375vdev_geom_open_by_path(vdev_t *vd, int check_guid)
376{
377 struct g_provider *pp;
378 struct g_consumer *cp;
379 uint64_t guid;
380
381 g_topology_assert();
382
383 cp = NULL;
384 pp = g_provider_by_name(vd->vdev_path + sizeof("/dev/") - 1);
385 if (pp != NULL) {
386 ZFS_LOG(1, "Found provider by name %s.", vd->vdev_path);
387 cp = vdev_geom_attach(pp);
388 if (cp != NULL && check_guid && ISP2(pp->sectorsize) &&
389 pp->sectorsize <= VDEV_PAD_SIZE) {
390 g_topology_unlock();
391 guid = vdev_geom_read_guid(cp);
392 g_topology_lock();
393 if (guid != vd->vdev_guid) {
394 vdev_geom_detach(cp, 0);
395 cp = NULL;
396 ZFS_LOG(1, "guid mismatch for provider %s: "
397 "%ju != %ju.", vd->vdev_path,
398 (uintmax_t)vd->vdev_guid, (uintmax_t)guid);
399 } else {
400 ZFS_LOG(1, "guid match for provider %s.",
401 vd->vdev_path);
402 }
403 }
404 }
405
406 return (cp);
407}
408
409static int
410vdev_geom_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize,
411 uint64_t *ashift)
412{
413 struct g_provider *pp;
414 struct g_consumer *cp;
415 size_t bufsize;
416 int error;
417
418 /*
419 * We must have a pathname, and it must be absolute.
420 */
421 if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') {
422 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
423 return (EINVAL);
424 }
425
426 vd->vdev_tsd = NULL;
427
428 DROP_GIANT();
429 g_topology_lock();
430 error = 0;
431
432 /*
433 * If we're creating or splitting a pool, just find the GEOM provider
434 * by its name and ignore GUID mismatches.
435 */
436 if (vd->vdev_spa->spa_load_state == SPA_LOAD_NONE ||
437 vd->vdev_spa->spa_splitting_newspa == B_TRUE)
438 cp = vdev_geom_open_by_path(vd, 0);
439 else {
440 cp = vdev_geom_open_by_path(vd, 1);
441 if (cp == NULL) {
442 /*
443 * The device at vd->vdev_path doesn't have the
444 * expected guid. The disks might have merely
445 * moved around so try all other GEOM providers
446 * to find one with the right guid.
447 */
448 cp = vdev_geom_open_by_guid(vd);
449 }
450 }
451
452 if (cp == NULL) {
453 ZFS_LOG(1, "Provider %s not found.", vd->vdev_path);
454 error = ENOENT;
455 } else if (cp->provider->sectorsize > VDEV_PAD_SIZE ||
456 !ISP2(cp->provider->sectorsize)) {
457 ZFS_LOG(1, "Provider %s has unsupported sectorsize.",
458 vd->vdev_path);
459 vdev_geom_detach(cp, 0);
460 error = EINVAL;
461 cp = NULL;
462 } else if (cp->acw == 0 && (spa_mode(vd->vdev_spa) & FWRITE) != 0) {
463 int i;
464
465 for (i = 0; i < 5; i++) {
466 error = g_access(cp, 0, 1, 0);
467 if (error == 0)
468 break;
469 g_topology_unlock();
470 tsleep(vd, 0, "vdev", hz / 2);
471 g_topology_lock();
472 }
473 if (error != 0) {
474 printf("ZFS WARNING: Unable to open %s for writing (error=%d).\n",
475 vd->vdev_path, error);
476 vdev_geom_detach(cp, 0);
477 cp = NULL;
478 }
479 }
480 g_topology_unlock();
481 PICKUP_GIANT();
482 if (cp == NULL) {
483 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
484 return (error);
485 }
486
487 cp->private = vd;
488 vd->vdev_tsd = cp;
489 pp = cp->provider;
490
491 /*
492 * Determine the actual size of the device.
493 */
494 *max_psize = *psize = pp->mediasize;
495
496 /*
497 * Determine the device's minimum transfer size.
498 */
499 *ashift = highbit(MAX(pp->sectorsize, SPA_MINBLOCKSIZE)) - 1;
500
501 /*
502 * Clear the nowritecache bit, so that on a vdev_reopen() we will
503 * try again.
504 */
505 vd->vdev_nowritecache = B_FALSE;
506
507 if (vd->vdev_physpath != NULL)
508 spa_strfree(vd->vdev_physpath);
509 bufsize = sizeof("/dev/") + strlen(pp->name);
510 vd->vdev_physpath = kmem_alloc(bufsize, KM_SLEEP);
511 snprintf(vd->vdev_physpath, bufsize, "/dev/%s", pp->name);
512
513 return (0);
514}
515
516static void
517vdev_geom_close(vdev_t *vd)
518{
519 struct g_consumer *cp;
520
521 cp = vd->vdev_tsd;
522 if (cp == NULL)
523 return;
524 vd->vdev_tsd = NULL;
525 vd->vdev_delayed_close = B_FALSE;
526 g_post_event(vdev_geom_detach, cp, M_WAITOK, NULL);
527}
528
529static void
530vdev_geom_io_intr(struct bio *bp)
531{
532 vdev_t *vd;
533 zio_t *zio;
534
535 zio = bp->bio_caller1;
536 vd = zio->io_vd;
537 zio->io_error = bp->bio_error;
538 if (zio->io_error == 0 && bp->bio_resid != 0)
539 zio->io_error = EIO;
540 if (bp->bio_cmd == BIO_FLUSH && bp->bio_error == ENOTSUP) {
541 /*
542 * If we get ENOTSUP, we know that no future
543 * attempts will ever succeed. In this case we
544 * set a persistent bit so that we don't bother
545 * with the ioctl in the future.
546 */
547 vd->vdev_nowritecache = B_TRUE;
548 }
549 if (zio->io_error == EIO && !vd->vdev_remove_wanted) {
550 /*
551 * If provider's error is set we assume it is being
552 * removed.
553 */
554 if (bp->bio_to->error != 0) {
555 /*
556 * We post the resource as soon as possible, instead of
557 * when the async removal actually happens, because the
558 * DE is using this information to discard previous I/O
559 * errors.
560 */
561 /* XXX: zfs_post_remove() can sleep. */
562 zfs_post_remove(zio->io_spa, vd);
563 vd->vdev_remove_wanted = B_TRUE;
564 spa_async_request(zio->io_spa, SPA_ASYNC_REMOVE);
565 } else if (!vd->vdev_delayed_close) {
566 vd->vdev_delayed_close = B_TRUE;
567 }
568 }
569 g_destroy_bio(bp);
570 zio_interrupt(zio);
571}
572
573static int
574vdev_geom_io_start(zio_t *zio)
575{
576 vdev_t *vd;
577 struct g_consumer *cp;
578 struct bio *bp;
579 int error;
580
581 vd = zio->io_vd;
582
583 if (zio->io_type == ZIO_TYPE_IOCTL) {
584 /* XXPOLICY */
585 if (!vdev_readable(vd)) {
586 zio->io_error = ENXIO;
587 return (ZIO_PIPELINE_CONTINUE);
588 }
589
590 switch (zio->io_cmd) {
591
592 case DKIOCFLUSHWRITECACHE:
593
594 if (zfs_nocacheflush || vdev_geom_bio_flush_disable)
595 break;
596
597 if (vd->vdev_nowritecache) {
598 zio->io_error = ENOTSUP;
599 break;
600 }
601
602 goto sendreq;
603 default:
604 zio->io_error = ENOTSUP;
605 }
606
607 return (ZIO_PIPELINE_CONTINUE);
608 }
609sendreq:
610 cp = vd->vdev_tsd;
611 if (cp == NULL) {
612 zio->io_error = ENXIO;
613 return (ZIO_PIPELINE_CONTINUE);
614 }
615 bp = g_alloc_bio();
616 bp->bio_caller1 = zio;
617 switch (zio->io_type) {
618 case ZIO_TYPE_READ:
619 case ZIO_TYPE_WRITE:
620 bp->bio_cmd = zio->io_type == ZIO_TYPE_READ ? BIO_READ : BIO_WRITE;
621 bp->bio_data = zio->io_data;
622 bp->bio_offset = zio->io_offset;
623 bp->bio_length = zio->io_size;
624 break;
625 case ZIO_TYPE_IOCTL:
626 bp->bio_cmd = BIO_FLUSH;
627 bp->bio_flags |= BIO_ORDERED;
628 bp->bio_data = NULL;
629 bp->bio_offset = cp->provider->mediasize;
630 bp->bio_length = 0;
631 break;
632 }
633 bp->bio_done = vdev_geom_io_intr;
634
635 g_io_request(bp, cp);
636
637 return (ZIO_PIPELINE_STOP);
638}
639
640static void
641vdev_geom_io_done(zio_t *zio)
642{
643}
644
645static void
646vdev_geom_hold(vdev_t *vd)
647{
648}
649
650static void
651vdev_geom_rele(vdev_t *vd)
652{
653}
654
655vdev_ops_t vdev_geom_ops = {
656 vdev_geom_open,
657 vdev_geom_close,
658 vdev_default_asize,
659 vdev_geom_io_start,
660 vdev_geom_io_done,
661 NULL,
662 vdev_geom_hold,
663 vdev_geom_rele,
664 VDEV_TYPE_DISK, /* name of this vdev type */
665 B_TRUE /* leaf vdev */
666};