diff options
Diffstat (limited to 'sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_mirror.c')
| -rw-r--r-- | sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_mirror.c | 779 |
1 files changed, 0 insertions, 779 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_mirror.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_mirror.c deleted file mode 100644 index 391cee87af08..000000000000 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_mirror.c +++ /dev/null @@ -1,779 +0,0 @@ -/* - * 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 2010 Sun Microsystems, Inc. All rights reserved. - * Use is subject to license terms. - */ - -/* - * Copyright (c) 2012, 2018 by Delphix. All rights reserved. - */ - -#include <sys/zfs_context.h> -#include <sys/spa.h> -#include <sys/spa_impl.h> -#include <sys/dsl_pool.h> -#include <sys/dsl_scan.h> -#include <sys/vdev_impl.h> -#include <sys/zio.h> -#include <sys/abd.h> -#include <sys/fs/zfs.h> - -/* - * Virtual device vector for mirroring. - */ - -typedef struct mirror_child { - vdev_t *mc_vd; - uint64_t mc_offset; - int mc_error; - int mc_load; - uint8_t mc_tried; - uint8_t mc_skipped; - uint8_t mc_speculative; -} mirror_child_t; - -typedef struct mirror_map { - int *mm_preferred; - int mm_preferred_cnt; - int mm_children; - boolean_t mm_resilvering; - boolean_t mm_root; - mirror_child_t mm_child[]; -} mirror_map_t; - -static int vdev_mirror_shift = 21; - -#ifdef _KERNEL -SYSCTL_DECL(_vfs_zfs_vdev); -static SYSCTL_NODE(_vfs_zfs_vdev, OID_AUTO, mirror, - CTLFLAG_RD | CTLFLAG_MPSAFE, 0, - "ZFS VDEV Mirror"); -#endif - -/* - * The load configuration settings below are tuned by default for - * the case where all devices are of the same rotational type. - * - * If there is a mixture of rotating and non-rotating media, setting - * non_rotating_seek_inc to 0 may well provide better results as it - * will direct more reads to the non-rotating vdevs which are more - * likely to have a higher performance. - */ - -/* Rotating media load calculation configuration. */ -static int rotating_inc = 0; -#ifdef _KERNEL -SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, rotating_inc, CTLFLAG_RWTUN, - &rotating_inc, 0, "Rotating media load increment for non-seeking I/O's"); -#endif - -static int rotating_seek_inc = 5; -#ifdef _KERNEL -SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, rotating_seek_inc, CTLFLAG_RWTUN, - &rotating_seek_inc, 0, "Rotating media load increment for seeking I/O's"); -#endif - -static int rotating_seek_offset = 1 * 1024 * 1024; -#ifdef _KERNEL -SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, rotating_seek_offset, CTLFLAG_RWTUN, - &rotating_seek_offset, 0, "Offset in bytes from the last I/O which " - "triggers a reduced rotating media seek increment"); -#endif - -/* Non-rotating media load calculation configuration. */ -static int non_rotating_inc = 0; -#ifdef _KERNEL -SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, non_rotating_inc, CTLFLAG_RWTUN, - &non_rotating_inc, 0, - "Non-rotating media load increment for non-seeking I/O's"); -#endif - -static int non_rotating_seek_inc = 1; -#ifdef _KERNEL -SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, non_rotating_seek_inc, CTLFLAG_RWTUN, - &non_rotating_seek_inc, 0, - "Non-rotating media load increment for seeking I/O's"); -#endif - - -static inline size_t -vdev_mirror_map_size(int children) -{ - return (offsetof(mirror_map_t, mm_child[children]) + - sizeof(int) * children); -} - -static inline mirror_map_t * -vdev_mirror_map_alloc(int children, boolean_t resilvering, boolean_t root) -{ - mirror_map_t *mm; - - mm = kmem_zalloc(vdev_mirror_map_size(children), KM_SLEEP); - mm->mm_children = children; - mm->mm_resilvering = resilvering; - mm->mm_root = root; - mm->mm_preferred = (int *)((uintptr_t)mm + - offsetof(mirror_map_t, mm_child[children])); - - return mm; -} - -static void -vdev_mirror_map_free(zio_t *zio) -{ - mirror_map_t *mm = zio->io_vsd; - - kmem_free(mm, vdev_mirror_map_size(mm->mm_children)); -} - -static const zio_vsd_ops_t vdev_mirror_vsd_ops = { - vdev_mirror_map_free, - zio_vsd_default_cksum_report -}; - -static int -vdev_mirror_load(mirror_map_t *mm, vdev_t *vd, uint64_t zio_offset) -{ - uint64_t lastoffset; - int load; - - /* All DVAs have equal weight at the root. */ - if (mm->mm_root) - return (INT_MAX); - - /* - * We don't return INT_MAX if the device is resilvering i.e. - * vdev_resilver_txg != 0 as when tested performance was slightly - * worse overall when resilvering with compared to without. - */ - - /* Standard load based on pending queue length. */ - load = vdev_queue_length(vd); - lastoffset = vdev_queue_lastoffset(vd); - - if (vd->vdev_nonrot) { - /* Non-rotating media. */ - if (lastoffset == zio_offset) - return (load + non_rotating_inc); - - /* - * Apply a seek penalty even for non-rotating devices as - * sequential I/O'a can be aggregated into fewer operations - * on the device, thus avoiding unnecessary per-command - * overhead and boosting performance. - */ - return (load + non_rotating_seek_inc); - } - - /* Rotating media I/O's which directly follow the last I/O. */ - if (lastoffset == zio_offset) - return (load + rotating_inc); - - /* - * Apply half the seek increment to I/O's within seek offset - * of the last I/O queued to this vdev as they should incure less - * of a seek increment. - */ - if (ABS(lastoffset - zio_offset) < rotating_seek_offset) - return (load + (rotating_seek_inc / 2)); - - /* Apply the full seek increment to all other I/O's. */ - return (load + rotating_seek_inc); -} - - -static mirror_map_t * -vdev_mirror_map_init(zio_t *zio) -{ - mirror_map_t *mm = NULL; - mirror_child_t *mc; - vdev_t *vd = zio->io_vd; - int c; - - if (vd == NULL) { - dva_t *dva = zio->io_bp->blk_dva; - spa_t *spa = zio->io_spa; - dva_t dva_copy[SPA_DVAS_PER_BP]; - - c = BP_GET_NDVAS(zio->io_bp); - - /* - * If we do not trust the pool config, some DVAs might be - * invalid or point to vdevs that do not exist. We skip them. - */ - if (!spa_trust_config(spa)) { - ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); - int j = 0; - for (int i = 0; i < c; i++) { - if (zfs_dva_valid(spa, &dva[i], zio->io_bp)) - dva_copy[j++] = dva[i]; - } - if (j == 0) { - zio->io_vsd = NULL; - zio->io_error = ENXIO; - return (NULL); - } - if (j < c) { - dva = dva_copy; - c = j; - } - } - - mm = vdev_mirror_map_alloc(c, B_FALSE, B_TRUE); - - for (c = 0; c < mm->mm_children; c++) { - mc = &mm->mm_child[c]; - mc->mc_vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[c])); - mc->mc_offset = DVA_GET_OFFSET(&dva[c]); - } - } else { - /* - * If we are resilvering, then we should handle scrub reads - * differently; we shouldn't issue them to the resilvering - * device because it might not have those blocks. - * - * We are resilvering iff: - * 1) We are a replacing vdev (ie our name is "replacing-1" or - * "spare-1" or something like that), and - * 2) The pool is currently being resilvered. - * - * We cannot simply check vd->vdev_resilver_txg, because it's - * not set in this path. - * - * Nor can we just check our vdev_ops; there are cases (such as - * when a user types "zpool replace pool odev spare_dev" and - * spare_dev is in the spare list, or when a spare device is - * automatically used to replace a DEGRADED device) when - * resilvering is complete but both the original vdev and the - * spare vdev remain in the pool. That behavior is intentional. - * It helps implement the policy that a spare should be - * automatically removed from the pool after the user replaces - * the device that originally failed. - * - * If a spa load is in progress, then spa_dsl_pool may be - * uninitialized. But we shouldn't be resilvering during a spa - * load anyway. - */ - boolean_t replacing = (vd->vdev_ops == &vdev_replacing_ops || - vd->vdev_ops == &vdev_spare_ops) && - spa_load_state(vd->vdev_spa) == SPA_LOAD_NONE && - dsl_scan_resilvering(vd->vdev_spa->spa_dsl_pool); - mm = vdev_mirror_map_alloc(vd->vdev_children, replacing, - B_FALSE); - for (c = 0; c < mm->mm_children; c++) { - mc = &mm->mm_child[c]; - mc->mc_vd = vd->vdev_child[c]; - mc->mc_offset = zio->io_offset; - } - } - - zio->io_vsd = mm; - zio->io_vsd_ops = &vdev_mirror_vsd_ops; - return (mm); -} - -static int -vdev_mirror_open(vdev_t *vd, uint64_t *asize, uint64_t *max_asize, - uint64_t *logical_ashift, uint64_t *physical_ashift) -{ - int numerrors = 0; - int lasterror = 0; - - if (vd->vdev_children == 0) { - vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; - return (SET_ERROR(EINVAL)); - } - - vdev_open_children(vd); - - for (int c = 0; c < vd->vdev_children; c++) { - vdev_t *cvd = vd->vdev_child[c]; - - if (cvd->vdev_open_error) { - lasterror = cvd->vdev_open_error; - numerrors++; - continue; - } - - *asize = MIN(*asize - 1, cvd->vdev_asize - 1) + 1; - *max_asize = MIN(*max_asize - 1, cvd->vdev_max_asize - 1) + 1; - *logical_ashift = MAX(*logical_ashift, cvd->vdev_ashift); - *physical_ashift = MAX(*physical_ashift, - cvd->vdev_physical_ashift); - } - - if (numerrors == vd->vdev_children) { - if (vdev_children_are_offline(vd)) - vd->vdev_stat.vs_aux = VDEV_AUX_CHILDREN_OFFLINE; - else - vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS; - return (lasterror); - } - - return (0); -} - -static void -vdev_mirror_close(vdev_t *vd) -{ - for (int c = 0; c < vd->vdev_children; c++) - vdev_close(vd->vdev_child[c]); -} - -static void -vdev_mirror_child_done(zio_t *zio) -{ - mirror_child_t *mc = zio->io_private; - - mc->mc_error = zio->io_error; - mc->mc_tried = 1; - mc->mc_skipped = 0; -} - -static void -vdev_mirror_scrub_done(zio_t *zio) -{ - mirror_child_t *mc = zio->io_private; - - if (zio->io_error == 0) { - zio_t *pio; - zio_link_t *zl = NULL; - - mutex_enter(&zio->io_lock); - while ((pio = zio_walk_parents(zio, &zl)) != NULL) { - mutex_enter(&pio->io_lock); - ASSERT3U(zio->io_size, >=, pio->io_size); - abd_copy(pio->io_abd, zio->io_abd, pio->io_size); - mutex_exit(&pio->io_lock); - } - mutex_exit(&zio->io_lock); - } - abd_free(zio->io_abd); - - mc->mc_error = zio->io_error; - mc->mc_tried = 1; - mc->mc_skipped = 0; -} - -/* - * Check the other, lower-index DVAs to see if they're on the same - * vdev as the child we picked. If they are, use them since they - * are likely to have been allocated from the primary metaslab in - * use at the time, and hence are more likely to have locality with - * single-copy data. - */ -static int -vdev_mirror_dva_select(zio_t *zio, int p) -{ - dva_t *dva = zio->io_bp->blk_dva; - mirror_map_t *mm = zio->io_vsd; - int preferred; - int c; - - preferred = mm->mm_preferred[p]; - for (p-- ; p >= 0; p--) { - c = mm->mm_preferred[p]; - if (DVA_GET_VDEV(&dva[c]) == DVA_GET_VDEV(&dva[preferred])) - preferred = c; - } - return (preferred); -} - -static int -vdev_mirror_preferred_child_randomize(zio_t *zio) -{ - mirror_map_t *mm = zio->io_vsd; - int p; - - if (mm->mm_root) { - p = spa_get_random(mm->mm_preferred_cnt); - return (vdev_mirror_dva_select(zio, p)); - } - - /* - * To ensure we don't always favour the first matching vdev, - * which could lead to wear leveling issues on SSD's, we - * use the I/O offset as a pseudo random seed into the vdevs - * which have the lowest load. - */ - p = (zio->io_offset >> vdev_mirror_shift) % mm->mm_preferred_cnt; - return (mm->mm_preferred[p]); -} - -/* - * Try to find a vdev whose DTL doesn't contain the block we want to read - * prefering vdevs based on determined load. - * - * If we can't, try the read on any vdev we haven't already tried. - */ -static int -vdev_mirror_child_select(zio_t *zio) -{ - mirror_map_t *mm = zio->io_vsd; - uint64_t txg = zio->io_txg; - int c, lowest_load; - - ASSERT(zio->io_bp == NULL || BP_PHYSICAL_BIRTH(zio->io_bp) == txg); - - lowest_load = INT_MAX; - mm->mm_preferred_cnt = 0; - for (c = 0; c < mm->mm_children; c++) { - mirror_child_t *mc; - - mc = &mm->mm_child[c]; - if (mc->mc_tried || mc->mc_skipped) - continue; - - if (!vdev_readable(mc->mc_vd)) { - mc->mc_error = SET_ERROR(ENXIO); - mc->mc_tried = 1; /* don't even try */ - mc->mc_skipped = 1; - continue; - } - - if (vdev_dtl_contains(mc->mc_vd, DTL_MISSING, txg, 1)) { - mc->mc_error = SET_ERROR(ESTALE); - mc->mc_skipped = 1; - mc->mc_speculative = 1; - continue; - } - - mc->mc_load = vdev_mirror_load(mm, mc->mc_vd, mc->mc_offset); - if (mc->mc_load > lowest_load) - continue; - - if (mc->mc_load < lowest_load) { - lowest_load = mc->mc_load; - mm->mm_preferred_cnt = 0; - } - mm->mm_preferred[mm->mm_preferred_cnt] = c; - mm->mm_preferred_cnt++; - } - - if (mm->mm_preferred_cnt == 1) { - vdev_queue_register_lastoffset( - mm->mm_child[mm->mm_preferred[0]].mc_vd, zio); - return (mm->mm_preferred[0]); - } - - if (mm->mm_preferred_cnt > 1) { - int c = vdev_mirror_preferred_child_randomize(zio); - - vdev_queue_register_lastoffset(mm->mm_child[c].mc_vd, zio); - return (c); - } - - /* - * Every device is either missing or has this txg in its DTL. - * Look for any child we haven't already tried before giving up. - */ - for (c = 0; c < mm->mm_children; c++) { - if (!mm->mm_child[c].mc_tried) { - vdev_queue_register_lastoffset(mm->mm_child[c].mc_vd, - zio); - return (c); - } - } - - /* - * Every child failed. There's no place left to look. - */ - return (-1); -} - -static void -vdev_mirror_io_start(zio_t *zio) -{ - mirror_map_t *mm; - mirror_child_t *mc; - int c, children; - - mm = vdev_mirror_map_init(zio); - - if (mm == NULL) { - ASSERT(!spa_trust_config(zio->io_spa)); - ASSERT(zio->io_type == ZIO_TYPE_READ); - zio_execute(zio); - return; - } - - if (zio->io_type == ZIO_TYPE_READ) { - if (zio->io_bp != NULL && - (zio->io_flags & ZIO_FLAG_SCRUB) && !mm->mm_resilvering && - mm->mm_children > 1) { - /* - * For scrubbing reads (if we can verify the - * checksum here, as indicated by io_bp being - * non-NULL) we need to allocate a read buffer for - * each child and issue reads to all children. If - * any child succeeds, it will copy its data into - * zio->io_data in vdev_mirror_scrub_done. - */ - for (c = 0; c < mm->mm_children; c++) { - mc = &mm->mm_child[c]; - zio_nowait(zio_vdev_child_io(zio, zio->io_bp, - mc->mc_vd, mc->mc_offset, - abd_alloc_sametype(zio->io_abd, - zio->io_size), zio->io_size, - zio->io_type, zio->io_priority, 0, - vdev_mirror_scrub_done, mc)); - } - zio_execute(zio); - return; - } - /* - * For normal reads just pick one child. - */ - c = vdev_mirror_child_select(zio); - children = (c >= 0); - } else { - ASSERT(zio->io_type == ZIO_TYPE_WRITE || - zio->io_type == ZIO_TYPE_FREE); - - /* - * Writes and frees go to all children. - */ - c = 0; - children = mm->mm_children; - } - - while (children--) { - mc = &mm->mm_child[c]; - zio_nowait(zio_vdev_child_io(zio, zio->io_bp, - mc->mc_vd, mc->mc_offset, zio->io_abd, zio->io_size, - zio->io_type, zio->io_priority, 0, - vdev_mirror_child_done, mc)); - c++; - } - - zio_execute(zio); -} - -static int -vdev_mirror_worst_error(mirror_map_t *mm) -{ - int error[2] = { 0, 0 }; - - for (int c = 0; c < mm->mm_children; c++) { - mirror_child_t *mc = &mm->mm_child[c]; - int s = mc->mc_speculative; - error[s] = zio_worst_error(error[s], mc->mc_error); - } - - return (error[0] ? error[0] : error[1]); -} - -static void -vdev_mirror_io_done(zio_t *zio) -{ - mirror_map_t *mm = zio->io_vsd; - mirror_child_t *mc; - int c; - int good_copies = 0; - int unexpected_errors = 0; - - if (mm == NULL) - return; - - for (c = 0; c < mm->mm_children; c++) { - mc = &mm->mm_child[c]; - - if (mc->mc_error) { - if (!mc->mc_skipped) - unexpected_errors++; - } else if (mc->mc_tried) { - good_copies++; - } - } - - if (zio->io_type == ZIO_TYPE_WRITE) { - /* - * XXX -- for now, treat partial writes as success. - * - * Now that we support write reallocation, it would be better - * to treat partial failure as real failure unless there are - * no non-degraded top-level vdevs left, and not update DTLs - * if we intend to reallocate. - */ - /* XXPOLICY */ - if (good_copies != mm->mm_children) { - /* - * Always require at least one good copy. - * - * For ditto blocks (io_vd == NULL), require - * all copies to be good. - * - * XXX -- for replacing vdevs, there's no great answer. - * If the old device is really dead, we may not even - * be able to access it -- so we only want to - * require good writes to the new device. But if - * the new device turns out to be flaky, we want - * to be able to detach it -- which requires all - * writes to the old device to have succeeded. - */ - if (good_copies == 0 || zio->io_vd == NULL) - zio->io_error = vdev_mirror_worst_error(mm); - } - return; - } else if (zio->io_type == ZIO_TYPE_FREE) { - return; - } - - ASSERT(zio->io_type == ZIO_TYPE_READ); - - /* - * If we don't have a good copy yet, keep trying other children. - */ - /* XXPOLICY */ - if (good_copies == 0 && (c = vdev_mirror_child_select(zio)) != -1) { - ASSERT(c >= 0 && c < mm->mm_children); - mc = &mm->mm_child[c]; - zio_vdev_io_redone(zio); - zio_nowait(zio_vdev_child_io(zio, zio->io_bp, - mc->mc_vd, mc->mc_offset, zio->io_abd, zio->io_size, - ZIO_TYPE_READ, zio->io_priority, 0, - vdev_mirror_child_done, mc)); - return; - } - - /* XXPOLICY */ - if (good_copies == 0) { - zio->io_error = vdev_mirror_worst_error(mm); - ASSERT(zio->io_error != 0); - } - - if (good_copies && spa_writeable(zio->io_spa) && - (unexpected_errors || - (zio->io_flags & ZIO_FLAG_RESILVER) || - ((zio->io_flags & ZIO_FLAG_SCRUB) && mm->mm_resilvering))) { - /* - * Use the good data we have in hand to repair damaged children. - */ - for (c = 0; c < mm->mm_children; c++) { - /* - * Don't rewrite known good children. - * Not only is it unnecessary, it could - * actually be harmful: if the system lost - * power while rewriting the only good copy, - * there would be no good copies left! - */ - mc = &mm->mm_child[c]; - - if (mc->mc_error == 0) { - if (mc->mc_tried) - continue; - /* - * We didn't try this child. We need to - * repair it if: - * 1. it's a scrub (in which case we have - * tried everything that was healthy) - * - or - - * 2. it's an indirect vdev (in which case - * it could point to any other vdev, which - * might have a bad DTL) - * - or - - * 3. the DTL indicates that this data is - * missing from this vdev - */ - if (!(zio->io_flags & ZIO_FLAG_SCRUB) && - mc->mc_vd->vdev_ops != &vdev_indirect_ops && - !vdev_dtl_contains(mc->mc_vd, DTL_PARTIAL, - zio->io_txg, 1)) - continue; - mc->mc_error = SET_ERROR(ESTALE); - } - - zio_nowait(zio_vdev_child_io(zio, zio->io_bp, - mc->mc_vd, mc->mc_offset, - zio->io_abd, zio->io_size, - ZIO_TYPE_WRITE, ZIO_PRIORITY_ASYNC_WRITE, - ZIO_FLAG_IO_REPAIR | (unexpected_errors ? - ZIO_FLAG_SELF_HEAL : 0), NULL, NULL)); - } - } -} - -static void -vdev_mirror_state_change(vdev_t *vd, int faulted, int degraded) -{ - if (faulted == vd->vdev_children) { - if (vdev_children_are_offline(vd)) { - vdev_set_state(vd, B_FALSE, VDEV_STATE_OFFLINE, - VDEV_AUX_CHILDREN_OFFLINE); - } else { - vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN, - VDEV_AUX_NO_REPLICAS); - } - } else if (degraded + faulted != 0) { - vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE); - } else { - vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE); - } -} - -vdev_ops_t vdev_mirror_ops = { - vdev_mirror_open, - vdev_mirror_close, - vdev_default_asize, - vdev_mirror_io_start, - vdev_mirror_io_done, - vdev_mirror_state_change, - NULL, - NULL, - NULL, - NULL, - vdev_default_xlate, - VDEV_TYPE_MIRROR, /* name of this vdev type */ - B_FALSE /* not a leaf vdev */ -}; - -vdev_ops_t vdev_replacing_ops = { - vdev_mirror_open, - vdev_mirror_close, - vdev_default_asize, - vdev_mirror_io_start, - vdev_mirror_io_done, - vdev_mirror_state_change, - NULL, - NULL, - NULL, - NULL, - vdev_default_xlate, - VDEV_TYPE_REPLACING, /* name of this vdev type */ - B_FALSE /* not a leaf vdev */ -}; - -vdev_ops_t vdev_spare_ops = { - vdev_mirror_open, - vdev_mirror_close, - vdev_default_asize, - vdev_mirror_io_start, - vdev_mirror_io_done, - vdev_mirror_state_change, - NULL, - NULL, - NULL, - NULL, - vdev_default_xlate, - VDEV_TYPE_SPARE, /* name of this vdev type */ - B_FALSE /* not a leaf vdev */ -}; |