/* * 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 https://opensource.org/licenses/CDDL-1.0. * 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, 2015 by Delphix. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include /* * Vdev mirror kstats */ static kstat_t *mirror_ksp = NULL; typedef struct mirror_stats { kstat_named_t vdev_mirror_stat_rotating_linear; kstat_named_t vdev_mirror_stat_rotating_offset; kstat_named_t vdev_mirror_stat_rotating_seek; kstat_named_t vdev_mirror_stat_non_rotating_linear; kstat_named_t vdev_mirror_stat_non_rotating_seek; kstat_named_t vdev_mirror_stat_preferred_found; kstat_named_t vdev_mirror_stat_preferred_not_found; } mirror_stats_t; static mirror_stats_t mirror_stats = { /* New I/O follows directly the last I/O */ { "rotating_linear", KSTAT_DATA_UINT64 }, /* New I/O is within zfs_vdev_mirror_rotating_seek_offset of the last */ { "rotating_offset", KSTAT_DATA_UINT64 }, /* New I/O requires random seek */ { "rotating_seek", KSTAT_DATA_UINT64 }, /* New I/O follows directly the last I/O (nonrot) */ { "non_rotating_linear", KSTAT_DATA_UINT64 }, /* New I/O requires random seek (nonrot) */ { "non_rotating_seek", KSTAT_DATA_UINT64 }, /* Preferred child vdev found */ { "preferred_found", KSTAT_DATA_UINT64 }, /* Preferred child vdev not found or equal load */ { "preferred_not_found", KSTAT_DATA_UINT64 }, }; #define MIRROR_STAT(stat) (mirror_stats.stat.value.ui64) #define MIRROR_INCR(stat, val) atomic_add_64(&MIRROR_STAT(stat), val) #define MIRROR_BUMP(stat) MIRROR_INCR(stat, 1) void vdev_mirror_stat_init(void) { mirror_ksp = kstat_create("zfs", 0, "vdev_mirror_stats", "misc", KSTAT_TYPE_NAMED, sizeof (mirror_stats) / sizeof (kstat_named_t), KSTAT_FLAG_VIRTUAL); if (mirror_ksp != NULL) { mirror_ksp->ks_data = &mirror_stats; kstat_install(mirror_ksp); } } void vdev_mirror_stat_fini(void) { if (mirror_ksp != NULL) { kstat_delete(mirror_ksp); mirror_ksp = NULL; } } /* * Virtual device vector for mirroring. */ typedef struct mirror_child { vdev_t *mc_vd; abd_t *mc_abd; uint64_t mc_offset; int mc_error; int mc_load; uint8_t mc_tried; uint8_t mc_skipped; uint8_t mc_speculative; uint8_t mc_rebuilding; } mirror_child_t; typedef struct mirror_map { int *mm_preferred; int mm_preferred_cnt; int mm_children; boolean_t mm_resilvering; boolean_t mm_rebuilding; boolean_t mm_root; mirror_child_t mm_child[]; } mirror_map_t; static const int vdev_mirror_shift = 21; /* * 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 * zfs_vdev_mirror_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 zfs_vdev_mirror_rotating_inc = 0; static int zfs_vdev_mirror_rotating_seek_inc = 5; static int zfs_vdev_mirror_rotating_seek_offset = 1 * 1024 * 1024; /* Non-rotating media load calculation configuration. */ static int zfs_vdev_mirror_non_rotating_inc = 0; static int zfs_vdev_mirror_non_rotating_seek_inc = 1; 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 = { .vsd_free = vdev_mirror_map_free, }; static int vdev_mirror_load(mirror_map_t *mm, vdev_t *vd, uint64_t zio_offset) { uint64_t last_offset; int64_t offset_diff; 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. */ /* Fix zio_offset for leaf vdevs */ if (vd->vdev_ops->vdev_op_leaf) zio_offset += VDEV_LABEL_START_SIZE; /* Standard load based on pending queue length. */ load = vdev_queue_length(vd); last_offset = vdev_queue_last_offset(vd); if (vd->vdev_nonrot) { /* Non-rotating media. */ if (last_offset == zio_offset) { MIRROR_BUMP(vdev_mirror_stat_non_rotating_linear); return (load + zfs_vdev_mirror_non_rotating_inc); } /* * Apply a seek penalty even for non-rotating devices as * sequential I/O's can be aggregated into fewer operations on * the device, thus avoiding unnecessary per-command overhead * and boosting performance. */ MIRROR_BUMP(vdev_mirror_stat_non_rotating_seek); return (load + zfs_vdev_mirror_non_rotating_seek_inc); } /* Rotating media I/O's which directly follow the last I/O. */ if (last_offset == zio_offset) { MIRROR_BUMP(vdev_mirror_stat_rotating_linear); return (load + zfs_vdev_mirror_rotating_inc); } /* * Apply half the seek increment to I/O's within seek offset * of the last I/O issued to this vdev as they should incur less * of a seek increment. */ offset_diff = (int64_t)(last_offset - zio_offset); if (ABS(offset_diff) < zfs_vdev_mirror_rotating_seek_offset) { MIRROR_BUMP(vdev_mirror_stat_rotating_offset); return (load + (zfs_vdev_mirror_rotating_seek_inc / 2)); } /* Apply the full seek increment to all other I/O's. */ MIRROR_BUMP(vdev_mirror_stat_rotating_seek); return (load + zfs_vdev_mirror_rotating_seek_inc); } static boolean_t vdev_mirror_rebuilding(vdev_t *vd) { if (vd->vdev_ops->vdev_op_leaf && vd->vdev_rebuild_txg) return (B_TRUE); for (int i = 0; i < vd->vdev_children; i++) { if (vdev_mirror_rebuilding(vd->vdev_child[i])) { return (B_TRUE); } } return (B_FALSE); } /* * Avoid inlining the function to keep vdev_mirror_io_start(), which * is this functions only caller, as small as possible on the stack. */ noinline 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; dsl_scan_t *scn = spa->spa_dsl_pool->dp_scan; dva_t dva_copy[SPA_DVAS_PER_BP]; /* * The sequential scrub code sorts and issues all DVAs * of a bp separately. Each of these IOs includes all * original DVA copies so that repairs can be performed * in the event of an error, but we only actually want * to check the first DVA since the others will be * checked by their respective sorted IOs. Only if we * hit an error will we try all DVAs upon retrying. * * Note: This check is safe even if the user switches * from a legacy scrub to a sequential one in the middle * of processing, since scn_is_sorted isn't updated until * all outstanding IOs from the previous scrub pass * complete. */ if ((zio->io_flags & ZIO_FLAG_SCRUB) && !(zio->io_flags & ZIO_FLAG_IO_RETRY) && dsl_scan_scrubbing(spa->spa_dsl_pool) && scn->scn_is_sorted) { c = 1; } else { c = BP_GET_NDVAS(zio->io_bp); } /* * If the pool cannot be written to, then infer that some * DVAs might be invalid or point to vdevs that do not exist. * We skip them. */ if (!spa_writeable(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]); if (mc->mc_vd == NULL) { kmem_free(mm, vdev_mirror_map_size( mm->mm_children)); zio->io_vsd = NULL; zio->io_error = ENXIO; return (NULL); } } } 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; if (vdev_mirror_rebuilding(mc->mc_vd)) mm->mm_rebuilding = mc->mc_rebuilding = B_TRUE; } } 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); } for (int c = 0; c < vd->vdev_children; c++) { vdev_t *cvd = vd->vdev_child[c]; if (cvd->vdev_open_error) continue; *physical_ashift = vdev_best_ashift(*logical_ashift, *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; } /* * 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 = random_in_range(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]); } static boolean_t vdev_mirror_child_readable(mirror_child_t *mc) { vdev_t *vd = mc->mc_vd; if (vd->vdev_top != NULL && vd->vdev_top->vdev_ops == &vdev_draid_ops) return (vdev_draid_readable(vd, mc->mc_offset)); else return (vdev_readable(vd)); } static boolean_t vdev_mirror_child_missing(mirror_child_t *mc, uint64_t txg, uint64_t size) { vdev_t *vd = mc->mc_vd; if (vd->vdev_top != NULL && vd->vdev_top->vdev_ops == &vdev_draid_ops) return (vdev_draid_missing(vd, mc->mc_offset, txg, size)); else return (vdev_dtl_contains(vd, DTL_MISSING, txg, size)); } /* * Try to find a vdev whose DTL doesn't contain the block we want to read * preferring vdevs based on determined load. If we can't, try the read on * any vdev we haven't already tried. * * Distributed spares are an exception to the above load rule. They are * always preferred in order to detect gaps in the distributed spare which * are created when another disk in the dRAID fails. In order to restore * redundancy those gaps must be read to trigger the required repair IO. */ 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_GET_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 (mc->mc_vd == NULL || !vdev_mirror_child_readable(mc)) { mc->mc_error = SET_ERROR(ENXIO); mc->mc_tried = 1; /* don't even try */ mc->mc_skipped = 1; continue; } if (vdev_mirror_child_missing(mc, txg, 1)) { mc->mc_error = SET_ERROR(ESTALE); mc->mc_skipped = 1; mc->mc_speculative = 1; continue; } if (mc->mc_vd->vdev_ops == &vdev_draid_spare_ops) { mm->mm_preferred[0] = c; mm->mm_preferred_cnt = 1; break; } 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) { MIRROR_BUMP(vdev_mirror_stat_preferred_found); return (mm->mm_preferred[0]); } if (mm->mm_preferred_cnt > 1) { MIRROR_BUMP(vdev_mirror_stat_preferred_not_found); return (vdev_mirror_preferred_child_randomize(zio)); } /* * 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) 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); zio->io_vsd = mm; zio->io_vsd_ops = &vdev_mirror_vsd_ops; 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_flags & ZIO_FLAG_SCRUB) && !mm->mm_resilvering) { /* * For scrubbing reads we need to issue reads to all * children. One child can reuse parent buffer, but * for others we have to allocate separate ones to * verify checksums if io_bp is non-NULL, or compare * them in vdev_mirror_io_done() otherwise. */ boolean_t first = B_TRUE; for (c = 0; c < mm->mm_children; c++) { mc = &mm->mm_child[c]; /* Don't issue ZIOs to offline children */ if (!vdev_mirror_child_readable(mc)) { mc->mc_error = SET_ERROR(ENXIO); mc->mc_tried = 1; mc->mc_skipped = 1; continue; } mc->mc_abd = first ? zio->io_abd : abd_alloc_sametype(zio->io_abd, zio->io_size); zio_nowait(zio_vdev_child_io(zio, zio->io_bp, mc->mc_vd, mc->mc_offset, mc->mc_abd, zio->io_size, zio->io_type, zio->io_priority, 0, vdev_mirror_child_done, mc)); first = B_FALSE; } 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); /* * Writes go to all children. */ c = 0; children = mm->mm_children; } while (children--) { mc = &mm->mm_child[c]; c++; /* * When sequentially resilvering only issue write repair * IOs to the vdev which is being rebuilt since performance * is limited by the slowest child. This is an issue for * faster replacement devices such as distributed spares. */ if ((zio->io_priority == ZIO_PRIORITY_REBUILD) && (zio->io_flags & ZIO_FLAG_IO_REPAIR) && !(zio->io_flags & ZIO_FLAG_SCRUB) && mm->mm_rebuilding && !mc->mc_rebuilding) { continue; } 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)); } 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; int last_good_copy = -1; 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) { last_good_copy = c; 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. */ 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; } ASSERT(zio->io_type == ZIO_TYPE_READ); /* * Any Direct I/O read that has a checksum error must be treated as * suspicious as the contents of the buffer could be getting * manipulated while the I/O is taking place. The checksum verify error * will be reported to the top-level Mirror VDEV. * * There will be no attampt at reading any additional data copies. If * the buffer is still being manipulated while attempting to read from * another child, there exists a possibly that the checksum could be * verified as valid. However, the buffer contents could again get * manipulated after verifying the checksum. This would lead to bad data * being written out during self healing. */ if ((zio->io_flags & ZIO_FLAG_DIO_READ) && (zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR)) { zio_dio_chksum_verify_error_report(zio); zio->io_error = vdev_mirror_worst_error(mm); ASSERT3U(zio->io_error, ==, ECKSUM); return; } /* * If we don't have a good copy yet, keep trying other children. */ 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; } if (zio->io_flags & ZIO_FLAG_SCRUB && !mm->mm_resilvering) { abd_t *best_abd = NULL; if (last_good_copy >= 0) best_abd = mm->mm_child[last_good_copy].mc_abd; /* * If we're scrubbing but don't have a BP available (because * this vdev is under a raidz or draid vdev) then the best we * can do is compare all of the copies read. If they're not * identical then return a checksum error and the most likely * correct data. The raidz code will issue a repair I/O if * possible. */ if (zio->io_bp == NULL) { ASSERT(zio->io_vd->vdev_ops == &vdev_replacing_ops || zio->io_vd->vdev_ops == &vdev_spare_ops); abd_t *pref_abd = NULL; for (c = 0; c < last_good_copy; c++) { mc = &mm->mm_child[c]; if (mc->mc_error || !mc->mc_tried) continue; if (abd_cmp(mc->mc_abd, best_abd) != 0) zio->io_error = SET_ERROR(ECKSUM); /* * The distributed spare is always prefered * by vdev_mirror_child_select() so it's * considered to be the best candidate. */ if (pref_abd == NULL && mc->mc_vd->vdev_ops == &vdev_draid_spare_ops) pref_abd = mc->mc_abd; /* * In the absence of a preferred copy, use * the parent pointer to avoid a memory copy. */ if (mc->mc_abd == zio->io_abd) best_abd = mc->mc_abd; } if (pref_abd) best_abd = pref_abd; } else { /* * If we have a BP available, then checksums are * already verified and we just need a buffer * with valid data, preferring parent one to * avoid a memory copy. */ for (c = 0; c < last_good_copy; c++) { mc = &mm->mm_child[c]; if (mc->mc_error || !mc->mc_tried) continue; if (mc->mc_abd == zio->io_abd) { best_abd = mc->mc_abd; break; } } } if (best_abd && best_abd != zio->io_abd) abd_copy(zio->io_abd, best_abd, zio->io_size); for (c = 0; c < mm->mm_children; c++) { mc = &mm->mm_child[c]; if (mc->mc_abd != zio->io_abd) abd_free(mc->mc_abd); mc->mc_abd = NULL; } } 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) { vdev_ops_t *ops = mc->mc_vd->vdev_ops; 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 or distributed spare * 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) && ops != &vdev_indirect_ops && ops != &vdev_draid_spare_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->io_priority == ZIO_PRIORITY_REBUILD ? ZIO_PRIORITY_REBUILD : 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); } } /* * Return the maximum asize for a rebuild zio in the provided range. */ static uint64_t vdev_mirror_rebuild_asize(vdev_t *vd, uint64_t start, uint64_t asize, uint64_t max_segment) { (void) start; uint64_t psize = MIN(P2ROUNDUP(max_segment, 1 << vd->vdev_ashift), SPA_MAXBLOCKSIZE); return (MIN(asize, vdev_psize_to_asize(vd, psize))); } vdev_ops_t vdev_mirror_ops = { .vdev_op_init = NULL, .vdev_op_fini = NULL, .vdev_op_open = vdev_mirror_open, .vdev_op_close = vdev_mirror_close, .vdev_op_asize = vdev_default_asize, .vdev_op_min_asize = vdev_default_min_asize, .vdev_op_min_alloc = NULL, .vdev_op_io_start = vdev_mirror_io_start, .vdev_op_io_done = vdev_mirror_io_done, .vdev_op_state_change = vdev_mirror_state_change, .vdev_op_need_resilver = vdev_default_need_resilver, .vdev_op_hold = NULL, .vdev_op_rele = NULL, .vdev_op_remap = NULL, .vdev_op_xlate = vdev_default_xlate, .vdev_op_rebuild_asize = vdev_mirror_rebuild_asize, .vdev_op_metaslab_init = NULL, .vdev_op_config_generate = NULL, .vdev_op_nparity = NULL, .vdev_op_ndisks = NULL, .vdev_op_type = VDEV_TYPE_MIRROR, /* name of this vdev type */ .vdev_op_leaf = B_FALSE /* not a leaf vdev */ }; vdev_ops_t vdev_replacing_ops = { .vdev_op_init = NULL, .vdev_op_fini = NULL, .vdev_op_open = vdev_mirror_open, .vdev_op_close = vdev_mirror_close, .vdev_op_asize = vdev_default_asize, .vdev_op_min_asize = vdev_default_min_asize, .vdev_op_min_alloc = NULL, .vdev_op_io_start = vdev_mirror_io_start, .vdev_op_io_done = vdev_mirror_io_done, .vdev_op_state_change = vdev_mirror_state_change, .vdev_op_need_resilver = vdev_default_need_resilver, .vdev_op_hold = NULL, .vdev_op_rele = NULL, .vdev_op_remap = NULL, .vdev_op_xlate = vdev_default_xlate, .vdev_op_rebuild_asize = vdev_mirror_rebuild_asize, .vdev_op_metaslab_init = NULL, .vdev_op_config_generate = NULL, .vdev_op_nparity = NULL, .vdev_op_ndisks = NULL, .vdev_op_type = VDEV_TYPE_REPLACING, /* name of this vdev type */ .vdev_op_leaf = B_FALSE /* not a leaf vdev */ }; vdev_ops_t vdev_spare_ops = { .vdev_op_init = NULL, .vdev_op_fini = NULL, .vdev_op_open = vdev_mirror_open, .vdev_op_close = vdev_mirror_close, .vdev_op_asize = vdev_default_asize, .vdev_op_min_asize = vdev_default_min_asize, .vdev_op_min_alloc = NULL, .vdev_op_io_start = vdev_mirror_io_start, .vdev_op_io_done = vdev_mirror_io_done, .vdev_op_state_change = vdev_mirror_state_change, .vdev_op_need_resilver = vdev_default_need_resilver, .vdev_op_hold = NULL, .vdev_op_rele = NULL, .vdev_op_remap = NULL, .vdev_op_xlate = vdev_default_xlate, .vdev_op_rebuild_asize = vdev_mirror_rebuild_asize, .vdev_op_metaslab_init = NULL, .vdev_op_config_generate = NULL, .vdev_op_nparity = NULL, .vdev_op_ndisks = NULL, .vdev_op_type = VDEV_TYPE_SPARE, /* name of this vdev type */ .vdev_op_leaf = B_FALSE /* not a leaf vdev */ }; ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, rotating_inc, INT, ZMOD_RW, "Rotating media load increment for non-seeking I/Os"); ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, rotating_seek_inc, INT, ZMOD_RW, "Rotating media load increment for seeking I/Os"); /* BEGIN CSTYLED */ ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, rotating_seek_offset, INT, ZMOD_RW, "Offset in bytes from the last I/O which triggers " "a reduced rotating media seek increment"); /* END CSTYLED */ ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, non_rotating_inc, INT, ZMOD_RW, "Non-rotating media load increment for non-seeking I/Os"); ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, non_rotating_seek_inc, INT, ZMOD_RW, "Non-rotating media load increment for seeking I/Os");