/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2006 Pawel Jakub Dawidek * All rights reserved. * * Portions Copyright (c) 2012 Martin Matuska */ #include #include #include #include #include #include #include #include #include #include #include #include /* * Virtual device vector for GEOM. */ static g_attrchanged_t vdev_geom_attrchanged; struct g_class zfs_vdev_class = { .name = "ZFS::VDEV", .version = G_VERSION, .attrchanged = vdev_geom_attrchanged, }; DECLARE_GEOM_CLASS(zfs_vdev_class, zfs_vdev); SYSCTL_DECL(_vfs_zfs_vdev); /* Don't send BIO_FLUSH. */ static int vdev_geom_bio_flush_disable; SYSCTL_INT(_vfs_zfs_vdev, OID_AUTO, bio_flush_disable, CTLFLAG_RWTUN, &vdev_geom_bio_flush_disable, 0, "Disable BIO_FLUSH"); /* Don't send BIO_DELETE. */ static int vdev_geom_bio_delete_disable; SYSCTL_INT(_vfs_zfs_vdev, OID_AUTO, bio_delete_disable, CTLFLAG_RWTUN, &vdev_geom_bio_delete_disable, 0, "Disable BIO_DELETE"); static void vdev_geom_set_rotation_rate(vdev_t *vd, struct g_consumer *cp) { int error; uint16_t rate; error = g_getattr("GEOM::rotation_rate", cp, &rate); if (error == 0) vd->vdev_rotation_rate = rate; else vd->vdev_rotation_rate = VDEV_RATE_UNKNOWN; } static void vdev_geom_attrchanged(struct g_consumer *cp, const char *attr) { vdev_t *vd; vd = cp->private; if (vd == NULL) return; if (strcmp(attr, "GEOM::rotation_rate") == 0) { vdev_geom_set_rotation_rate(vd, cp); return; } } static void vdev_geom_orphan(struct g_consumer *cp) { vdev_t *vd; g_topology_assert(); vd = cp->private; if (vd == NULL) return; /* * Orphan callbacks occur from the GEOM event thread. * Concurrent with this call, new I/O requests may be * working their way through GEOM about to find out * (only once executed by the g_down thread) that we've * been orphaned from our disk provider. These I/Os * must be retired before we can detach our consumer. * This is most easily achieved by acquiring the * SPA ZIO configuration lock as a writer, but doing * so with the GEOM topology lock held would cause * a lock order reversal. Instead, rely on the SPA's * async removal support to invoke a close on this * vdev once it is safe to do so. */ zfs_post_remove(vd->vdev_spa, vd); vd->vdev_remove_wanted = B_TRUE; spa_async_request(vd->vdev_spa, SPA_ASYNC_REMOVE); } static struct g_consumer * vdev_geom_attach(struct g_provider *pp) { struct g_geom *gp; struct g_consumer *cp; g_topology_assert(); ZFS_LOG(1, "Attaching to %s.", pp->name); /* Do we have geom already? No? Create one. */ LIST_FOREACH(gp, &zfs_vdev_class.geom, geom) { if (gp->flags & G_GEOM_WITHER) continue; if (strcmp(gp->name, "zfs::vdev") != 0) continue; break; } if (gp == NULL) { gp = g_new_geomf(&zfs_vdev_class, "zfs::vdev"); gp->orphan = vdev_geom_orphan; cp = g_new_consumer(gp); if (g_attach(cp, pp) != 0) { g_wither_geom(gp, ENXIO); return (NULL); } if (g_access(cp, 1, 0, 1) != 0) { g_wither_geom(gp, ENXIO); return (NULL); } ZFS_LOG(1, "Created geom and consumer for %s.", pp->name); } else { /* Check if we are already connected to this provider. */ LIST_FOREACH(cp, &gp->consumer, consumer) { if (cp->provider == pp) { ZFS_LOG(1, "Found consumer for %s.", pp->name); break; } } if (cp == NULL) { cp = g_new_consumer(gp); if (g_attach(cp, pp) != 0) { g_destroy_consumer(cp); return (NULL); } if (g_access(cp, 1, 0, 1) != 0) { g_detach(cp); g_destroy_consumer(cp); return (NULL); } ZFS_LOG(1, "Created consumer for %s.", pp->name); } else { if (g_access(cp, 1, 0, 1) != 0) return (NULL); ZFS_LOG(1, "Used existing consumer for %s.", pp->name); } } cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE; return (cp); } static void vdev_geom_detach(void *arg, int flag __unused) { struct g_geom *gp; struct g_consumer *cp; g_topology_assert(); cp = arg; gp = cp->geom; ZFS_LOG(1, "Closing access to %s.", cp->provider->name); g_access(cp, -1, 0, -1); /* Destroy consumer on last close. */ if (cp->acr == 0 && cp->ace == 0) { ZFS_LOG(1, "Destroyed consumer to %s.", cp->provider->name); if (cp->acw > 0) g_access(cp, 0, -cp->acw, 0); g_detach(cp); g_destroy_consumer(cp); } /* Destroy geom if there are no consumers left. */ if (LIST_EMPTY(&gp->consumer)) { ZFS_LOG(1, "Destroyed geom %s.", gp->name); g_wither_geom(gp, ENXIO); } } static void nvlist_get_guids(nvlist_t *list, uint64_t *pguid, uint64_t *vguid) { nvlist_lookup_uint64(list, ZPOOL_CONFIG_GUID, vguid); nvlist_lookup_uint64(list, ZPOOL_CONFIG_POOL_GUID, pguid); } static int vdev_geom_io(struct g_consumer *cp, int cmd, void *data, off_t offset, off_t size) { struct bio *bp; u_char *p; off_t off, maxio; int error; ASSERT((offset % cp->provider->sectorsize) == 0); ASSERT((size % cp->provider->sectorsize) == 0); bp = g_alloc_bio(); off = offset; offset += size; p = data; maxio = MAXPHYS - (MAXPHYS % cp->provider->sectorsize); error = 0; for (; off < offset; off += maxio, p += maxio, size -= maxio) { bzero(bp, sizeof(*bp)); bp->bio_cmd = cmd; bp->bio_done = NULL; bp->bio_offset = off; bp->bio_length = MIN(size, maxio); bp->bio_data = p; g_io_request(bp, cp); error = biowait(bp, "vdev_geom_io"); if (error != 0) break; } g_destroy_bio(bp); return (error); } static void vdev_geom_taste_orphan(struct g_consumer *cp) { KASSERT(1 == 0, ("%s called while tasting %s.", __func__, cp->provider->name)); } static int vdev_geom_read_config(struct g_consumer *cp, nvlist_t **config) { struct g_provider *pp; vdev_label_t *label; char *p, *buf; size_t buflen; uint64_t psize; off_t offset, size; uint64_t state, txg; int error, l, len; g_topology_assert_not(); pp = cp->provider; ZFS_LOG(1, "Reading config from %s...", pp->name); psize = pp->mediasize; psize = P2ALIGN(psize, (uint64_t)sizeof(vdev_label_t)); size = sizeof(*label) + pp->sectorsize - ((sizeof(*label) - 1) % pp->sectorsize) - 1; label = kmem_alloc(size, KM_SLEEP); buflen = sizeof(label->vl_vdev_phys.vp_nvlist); *config = NULL; for (l = 0; l < VDEV_LABELS; l++) { offset = vdev_label_offset(psize, l, 0); if ((offset % pp->sectorsize) != 0) continue; if (vdev_geom_io(cp, BIO_READ, label, offset, size) != 0) continue; buf = label->vl_vdev_phys.vp_nvlist; if (nvlist_unpack(buf, buflen, config, 0) != 0) continue; if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_STATE, &state) != 0 || state > POOL_STATE_L2CACHE) { nvlist_free(*config); *config = NULL; continue; } if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE && (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG, &txg) != 0 || txg == 0)) { nvlist_free(*config); *config = NULL; continue; } break; } kmem_free(label, size); return (*config == NULL ? ENOENT : 0); } static void resize_configs(nvlist_t ***configs, uint64_t *count, uint64_t id) { nvlist_t **new_configs; uint64_t i; if (id < *count) return; new_configs = kmem_zalloc((id + 1) * sizeof(nvlist_t *), KM_SLEEP); for (i = 0; i < *count; i++) new_configs[i] = (*configs)[i]; if (*configs != NULL) kmem_free(*configs, *count * sizeof(void *)); *configs = new_configs; *count = id + 1; } static void process_vdev_config(nvlist_t ***configs, uint64_t *count, nvlist_t *cfg, const char *name, uint64_t* known_pool_guid) { nvlist_t *vdev_tree; uint64_t pool_guid; uint64_t vdev_guid, known_guid; uint64_t id, txg, known_txg; char *pname; int i; if (nvlist_lookup_string(cfg, ZPOOL_CONFIG_POOL_NAME, &pname) != 0 || strcmp(pname, name) != 0) goto ignore; if (nvlist_lookup_uint64(cfg, ZPOOL_CONFIG_POOL_GUID, &pool_guid) != 0) goto ignore; if (nvlist_lookup_uint64(cfg, ZPOOL_CONFIG_TOP_GUID, &vdev_guid) != 0) goto ignore; if (nvlist_lookup_nvlist(cfg, ZPOOL_CONFIG_VDEV_TREE, &vdev_tree) != 0) goto ignore; if (nvlist_lookup_uint64(vdev_tree, ZPOOL_CONFIG_ID, &id) != 0) goto ignore; VERIFY(nvlist_lookup_uint64(cfg, ZPOOL_CONFIG_POOL_TXG, &txg) == 0); if (*known_pool_guid != 0) { if (pool_guid != *known_pool_guid) goto ignore; } else *known_pool_guid = pool_guid; resize_configs(configs, count, id); if ((*configs)[id] != NULL) { VERIFY(nvlist_lookup_uint64((*configs)[id], ZPOOL_CONFIG_POOL_TXG, &known_txg) == 0); if (txg <= known_txg) goto ignore; nvlist_free((*configs)[id]); } (*configs)[id] = cfg; return; ignore: nvlist_free(cfg); } static int vdev_geom_attach_taster(struct g_consumer *cp, struct g_provider *pp) { int error; if (pp->flags & G_PF_WITHER) return (EINVAL); g_attach(cp, pp); error = g_access(cp, 1, 0, 0); if (error == 0) { if (pp->sectorsize > VDEV_PAD_SIZE || !ISP2(pp->sectorsize)) error = EINVAL; else if (pp->mediasize < SPA_MINDEVSIZE) error = EINVAL; if (error != 0) g_access(cp, -1, 0, 0); } if (error != 0) g_detach(cp); return (error); } static void vdev_geom_detach_taster(struct g_consumer *cp) { g_access(cp, -1, 0, 0); g_detach(cp); } int vdev_geom_read_pool_label(const char *name, nvlist_t ***configs, uint64_t *count) { struct g_class *mp; struct g_geom *gp, *zgp; struct g_provider *pp; struct g_consumer *zcp; nvlist_t *vdev_cfg; uint64_t pool_guid; int error; DROP_GIANT(); g_topology_lock(); zgp = g_new_geomf(&zfs_vdev_class, "zfs::vdev::taste"); /* This orphan function should be never called. */ zgp->orphan = vdev_geom_taste_orphan; zcp = g_new_consumer(zgp); *configs = NULL; *count = 0; pool_guid = 0; LIST_FOREACH(mp, &g_classes, class) { if (mp == &zfs_vdev_class) continue; LIST_FOREACH(gp, &mp->geom, geom) { if (gp->flags & G_GEOM_WITHER) continue; LIST_FOREACH(pp, &gp->provider, provider) { if (pp->flags & G_PF_WITHER) continue; if (vdev_geom_attach_taster(zcp, pp) != 0) continue; g_topology_unlock(); error = vdev_geom_read_config(zcp, &vdev_cfg); g_topology_lock(); vdev_geom_detach_taster(zcp); if (error) continue; ZFS_LOG(1, "successfully read vdev config"); process_vdev_config(configs, count, vdev_cfg, name, &pool_guid); } } } g_destroy_consumer(zcp); g_destroy_geom(zgp); g_topology_unlock(); PICKUP_GIANT(); return (*count > 0 ? 0 : ENOENT); } static void vdev_geom_read_guids(struct g_consumer *cp, uint64_t *pguid, uint64_t *vguid) { nvlist_t *config; g_topology_assert_not(); *pguid = 0; *vguid = 0; if (vdev_geom_read_config(cp, &config) == 0) { nvlist_get_guids(config, pguid, vguid); nvlist_free(config); } } static struct g_consumer * vdev_geom_attach_by_guids(uint64_t pool_guid, uint64_t vdev_guid) { struct g_class *mp; struct g_geom *gp, *zgp; struct g_provider *pp; struct g_consumer *cp, *zcp; uint64_t pguid, vguid; g_topology_assert(); zgp = g_new_geomf(&zfs_vdev_class, "zfs::vdev::taste"); /* This orphan function should be never called. */ zgp->orphan = vdev_geom_taste_orphan; zcp = g_new_consumer(zgp); cp = NULL; LIST_FOREACH(mp, &g_classes, class) { if (mp == &zfs_vdev_class) continue; LIST_FOREACH(gp, &mp->geom, geom) { if (gp->flags & G_GEOM_WITHER) continue; LIST_FOREACH(pp, &gp->provider, provider) { if (vdev_geom_attach_taster(zcp, pp) != 0) continue; g_topology_unlock(); vdev_geom_read_guids(zcp, &pguid, &vguid); g_topology_lock(); vdev_geom_detach_taster(zcp); if (pguid != pool_guid || vguid != vdev_guid) continue; cp = vdev_geom_attach(pp); if (cp == NULL) { printf("ZFS WARNING: Unable to " "attach to %s.\n", pp->name); continue; } break; } if (cp != NULL) break; } if (cp != NULL) break; } end: g_destroy_consumer(zcp); g_destroy_geom(zgp); return (cp); } static struct g_consumer * vdev_geom_open_by_guids(vdev_t *vd) { struct g_consumer *cp; char *buf; size_t len; g_topology_assert(); ZFS_LOG(1, "Searching by guid [%ju].", (uintmax_t)vd->vdev_guid); cp = vdev_geom_attach_by_guids(spa_guid(vd->vdev_spa), vd->vdev_guid); if (cp != NULL) { len = strlen(cp->provider->name) + strlen("/dev/") + 1; buf = kmem_alloc(len, KM_SLEEP); snprintf(buf, len, "/dev/%s", cp->provider->name); spa_strfree(vd->vdev_path); vd->vdev_path = buf; ZFS_LOG(1, "Attach by guid [%ju:%ju] succeeded, provider %s.", (uintmax_t)spa_guid(vd->vdev_spa), (uintmax_t)vd->vdev_guid, vd->vdev_path); } else { ZFS_LOG(1, "Search by guid [%ju:%ju] failed.", (uintmax_t)spa_guid(vd->vdev_spa), (uintmax_t)vd->vdev_guid); } return (cp); } static struct g_consumer * vdev_geom_open_by_path(vdev_t *vd, int check_guid) { struct g_provider *pp; struct g_consumer *cp; uint64_t pguid, vguid; g_topology_assert(); cp = NULL; pp = g_provider_by_name(vd->vdev_path + sizeof("/dev/") - 1); if (pp != NULL) { ZFS_LOG(1, "Found provider by name %s.", vd->vdev_path); cp = vdev_geom_attach(pp); if (cp != NULL && check_guid && ISP2(pp->sectorsize) && pp->sectorsize <= VDEV_PAD_SIZE) { g_topology_unlock(); vdev_geom_read_guids(cp, &pguid, &vguid); g_topology_lock(); if (pguid != spa_guid(vd->vdev_spa) || vguid != vd->vdev_guid) { vdev_geom_detach(cp, 0); cp = NULL; ZFS_LOG(1, "guid mismatch for provider %s: " "%ju:%ju != %ju:%ju.", vd->vdev_path, (uintmax_t)spa_guid(vd->vdev_spa), (uintmax_t)vd->vdev_guid, (uintmax_t)pguid, (uintmax_t)vguid); } else { ZFS_LOG(1, "guid match for provider %s.", vd->vdev_path); } } } return (cp); } static int vdev_geom_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize, uint64_t *logical_ashift, uint64_t *physical_ashift) { struct g_provider *pp; struct g_consumer *cp; size_t bufsize; int error; /* * We must have a pathname, and it must be absolute. */ if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') { vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; return (EINVAL); } vd->vdev_tsd = NULL; DROP_GIANT(); g_topology_lock(); error = 0; if (vd->vdev_spa->spa_splitting_newspa || (vd->vdev_prevstate == VDEV_STATE_UNKNOWN && vd->vdev_spa->spa_load_state == SPA_LOAD_NONE)) { /* * We are dealing with a vdev that hasn't been previously * opened (since boot), and we are not loading an * existing pool configuration. This looks like a * vdev add operation to a new or existing pool. * Assume the user knows what he/she is doing and find * GEOM provider by its name, ignoring GUID mismatches. * * XXPOLICY: It would be safer to only allow a device * that is unlabeled or labeled but missing * GUID information to be opened in this fashion, * unless we are doing a split, in which case we * should allow any guid. */ cp = vdev_geom_open_by_path(vd, 0); } else { /* * Try using the recorded path for this device, but only * accept it if its label data contains the expected GUIDs. */ cp = vdev_geom_open_by_path(vd, 1); if (cp == NULL) { /* * The device at vd->vdev_path doesn't have the * expected GUIDs. The disks might have merely * moved around so try all other GEOM providers * to find one with the right GUIDs. */ cp = vdev_geom_open_by_guids(vd); } } if (cp == NULL) { ZFS_LOG(1, "Provider %s not found.", vd->vdev_path); error = ENOENT; } else if (cp->provider->sectorsize > VDEV_PAD_SIZE || !ISP2(cp->provider->sectorsize)) { ZFS_LOG(1, "Provider %s has unsupported sectorsize.", vd->vdev_path); vdev_geom_detach(cp, 0); error = EINVAL; cp = NULL; } else if (cp->acw == 0 && (spa_mode(vd->vdev_spa) & FWRITE) != 0) { int i; for (i = 0; i < 5; i++) { error = g_access(cp, 0, 1, 0); if (error == 0) break; g_topology_unlock(); tsleep(vd, 0, "vdev", hz / 2); g_topology_lock(); } if (error != 0) { printf("ZFS WARNING: Unable to open %s for writing (error=%d).\n", vd->vdev_path, error); vdev_geom_detach(cp, 0); cp = NULL; } } g_topology_unlock(); PICKUP_GIANT(); if (cp == NULL) { vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; return (error); } cp->private = vd; vd->vdev_tsd = cp; pp = cp->provider; /* * Determine the actual size of the device. */ *max_psize = *psize = pp->mediasize; /* * Determine the device's minimum transfer size and preferred * transfer size. */ *logical_ashift = highbit(MAX(pp->sectorsize, SPA_MINBLOCKSIZE)) - 1; *physical_ashift = 0; if (pp->stripesize) *physical_ashift = highbit(pp->stripesize) - 1; /* * Clear the nowritecache settings, so that on a vdev_reopen() * we will try again. */ vd->vdev_nowritecache = B_FALSE; if (vd->vdev_physpath != NULL) spa_strfree(vd->vdev_physpath); bufsize = sizeof("/dev/") + strlen(pp->name); vd->vdev_physpath = kmem_alloc(bufsize, KM_SLEEP); snprintf(vd->vdev_physpath, bufsize, "/dev/%s", pp->name); /* * Determine the device's rotation rate. */ vdev_geom_set_rotation_rate(vd, cp); return (0); } static void vdev_geom_close(vdev_t *vd) { struct g_consumer *cp; cp = vd->vdev_tsd; if (cp == NULL) return; vd->vdev_tsd = NULL; vd->vdev_delayed_close = B_FALSE; cp->private = NULL; /* XXX locking */ g_post_event(vdev_geom_detach, cp, M_WAITOK, NULL); } static void vdev_geom_io_intr(struct bio *bp) { vdev_t *vd; zio_t *zio; zio = bp->bio_caller1; vd = zio->io_vd; zio->io_error = bp->bio_error; if (zio->io_error == 0 && bp->bio_resid != 0) zio->io_error = SET_ERROR(EIO); switch(zio->io_error) { case ENOTSUP: /* * If we get ENOTSUP for BIO_FLUSH or BIO_DELETE we know * that future attempts will never succeed. In this case * we set a persistent flag so that we don't bother with * requests in the future. */ switch(bp->bio_cmd) { case BIO_FLUSH: vd->vdev_nowritecache = B_TRUE; break; case BIO_DELETE: vd->vdev_notrim = B_TRUE; break; } break; case ENXIO: if (!vd->vdev_remove_wanted) { /* * If provider's error is set we assume it is being * removed. */ if (bp->bio_to->error != 0) { vd->vdev_remove_wanted = B_TRUE; spa_async_request(zio->io_spa, SPA_ASYNC_REMOVE); } else if (!vd->vdev_delayed_close) { vd->vdev_delayed_close = B_TRUE; } } break; } g_destroy_bio(bp); zio_interrupt(zio); } static void vdev_geom_io_start(zio_t *zio) { vdev_t *vd; struct g_consumer *cp; struct bio *bp; int error; vd = zio->io_vd; switch (zio->io_type) { case ZIO_TYPE_IOCTL: /* XXPOLICY */ if (!vdev_readable(vd)) { zio->io_error = SET_ERROR(ENXIO); zio_interrupt(zio); return; } else { switch (zio->io_cmd) { case DKIOCFLUSHWRITECACHE: if (zfs_nocacheflush || vdev_geom_bio_flush_disable) break; if (vd->vdev_nowritecache) { zio->io_error = SET_ERROR(ENOTSUP); break; } goto sendreq; default: zio->io_error = SET_ERROR(ENOTSUP); } } zio_execute(zio); return; case ZIO_TYPE_FREE: if (vd->vdev_notrim) { zio->io_error = SET_ERROR(ENOTSUP); } else if (!vdev_geom_bio_delete_disable) { goto sendreq; } zio_execute(zio); return; } sendreq: ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE || zio->io_type == ZIO_TYPE_FREE || zio->io_type == ZIO_TYPE_IOCTL); cp = vd->vdev_tsd; if (cp == NULL) { zio->io_error = SET_ERROR(ENXIO); zio_interrupt(zio); return; } bp = g_alloc_bio(); bp->bio_caller1 = zio; switch (zio->io_type) { case ZIO_TYPE_READ: case ZIO_TYPE_WRITE: bp->bio_cmd = zio->io_type == ZIO_TYPE_READ ? BIO_READ : BIO_WRITE; bp->bio_data = zio->io_data; bp->bio_offset = zio->io_offset; bp->bio_length = zio->io_size; break; case ZIO_TYPE_FREE: bp->bio_cmd = BIO_DELETE; bp->bio_data = NULL; bp->bio_offset = zio->io_offset; bp->bio_length = zio->io_size; break; case ZIO_TYPE_IOCTL: bp->bio_cmd = BIO_FLUSH; bp->bio_flags |= BIO_ORDERED; bp->bio_data = NULL; bp->bio_offset = cp->provider->mediasize; bp->bio_length = 0; break; } bp->bio_done = vdev_geom_io_intr; g_io_request(bp, cp); } static void vdev_geom_io_done(zio_t *zio) { } static void vdev_geom_hold(vdev_t *vd) { } static void vdev_geom_rele(vdev_t *vd) { } vdev_ops_t vdev_geom_ops = { vdev_geom_open, vdev_geom_close, vdev_default_asize, vdev_geom_io_start, vdev_geom_io_done, NULL, vdev_geom_hold, vdev_geom_rele, VDEV_TYPE_DISK, /* name of this vdev type */ B_TRUE /* leaf vdev */ };