From 716529c475152eaae4ef454e1476a99204014991 Mon Sep 17 00:00:00 2001 From: mav Date: Wed, 3 Oct 2018 02:11:05 +0000 Subject: [PATCH] MFC r336951: MFV r336950: 9290 device removal reduces redundancy of mirrors Mirrors are supposed to provide redundancy in the face of whole-disk failure and silent damage (e.g. some data on disk is not right, but ZFS hasn't detected the whole device as being broken). However, the current device removal implementation bypasses some of the mirror's redundancy. illumos/illumos-gate@3a4b1be953ee5601bab748afa07c26ed4996cde6 Reviewed by: George Wilson Reviewed by: Prashanth Sreenivasa Reviewed by: Sara Hartse Reviewed by: Serapheim Dimitropoulos Reviewed by: Brian Behlendorf Reviewed by: Tim Chase Approved by: Richard Lowe Author: Matthew Ahrens --- cddl/contrib/opensolaris/cmd/zdb/zdb.c | 18 +- cddl/contrib/opensolaris/cmd/ztest/ztest.c | 58 +- .../lib/libzfs/common/libzfs_pool.c | 2 +- .../opensolaris/uts/common/fs/zfs/dsl_scan.c | 10 + .../opensolaris/uts/common/fs/zfs/metaslab.c | 2 +- .../opensolaris/uts/common/fs/zfs/spa.c | 7 +- .../opensolaris/uts/common/fs/zfs/spa_misc.c | 5 +- .../uts/common/fs/zfs/sys/vdev_removal.h | 2 +- .../opensolaris/uts/common/fs/zfs/sys/zio.h | 2 +- .../opensolaris/uts/common/fs/zfs/vdev.c | 26 + .../uts/common/fs/zfs/vdev_indirect.c | 552 +++++++++++++++++- .../uts/common/fs/zfs/vdev_mirror.c | 29 +- .../uts/common/fs/zfs/vdev_removal.c | 361 ++++++------ .../opensolaris/uts/common/fs/zfs/zio.c | 54 +- 14 files changed, 898 insertions(+), 230 deletions(-) diff --git a/cddl/contrib/opensolaris/cmd/zdb/zdb.c b/cddl/contrib/opensolaris/cmd/zdb/zdb.c index a0d3be3e77c..1a82bb2d5ad 100644 --- a/cddl/contrib/opensolaris/cmd/zdb/zdb.c +++ b/cddl/contrib/opensolaris/cmd/zdb/zdb.c @@ -3033,7 +3033,7 @@ zdb_claim_removing(spa_t *spa, zdb_cb_t *zcb) spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER); spa_vdev_removal_t *svr = spa->spa_vdev_removal; - vdev_t *vd = svr->svr_vdev; + vdev_t *vd = vdev_lookup_top(spa, svr->svr_vdev_id); vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping; for (uint64_t msi = 0; msi < vd->vdev_ms_count; msi++) { @@ -3049,13 +3049,17 @@ zdb_claim_removing(spa_t *spa, zdb_cb_t *zcb) svr->svr_allocd_segs, SM_ALLOC)); /* - * Clear everything past what has been synced, - * because we have not allocated mappings for it yet. + * Clear everything past what has been synced unless + * it's past the spacemap, because we have not allocated + * mappings for it yet. */ - range_tree_clear(svr->svr_allocd_segs, - vdev_indirect_mapping_max_offset(vim), - msp->ms_sm->sm_start + msp->ms_sm->sm_size - - vdev_indirect_mapping_max_offset(vim)); + uint64_t vim_max_offset = + vdev_indirect_mapping_max_offset(vim); + uint64_t sm_end = msp->ms_sm->sm_start + + msp->ms_sm->sm_size; + if (sm_end > vim_max_offset) + range_tree_clear(svr->svr_allocd_segs, + vim_max_offset, sm_end - vim_max_offset); } zcb->zcb_removing_size += diff --git a/cddl/contrib/opensolaris/cmd/ztest/ztest.c b/cddl/contrib/opensolaris/cmd/ztest/ztest.c index 9536df56f22..deb5763ed0e 100644 --- a/cddl/contrib/opensolaris/cmd/ztest/ztest.c +++ b/cddl/contrib/opensolaris/cmd/ztest/ztest.c @@ -438,6 +438,7 @@ static ztest_ds_t *ztest_ds; static kmutex_t ztest_vdev_lock; static kmutex_t ztest_checkpoint_lock; +static boolean_t ztest_device_removal_active = B_FALSE; /* * The ztest_name_lock protects the pool and dataset namespace used by @@ -2882,7 +2883,7 @@ ztest_vdev_attach_detach(ztest_ds_t *zd, uint64_t id) * value. Don't bother trying to attach while we are in the middle * of removal. */ - if (spa->spa_vdev_removal != NULL) { + if (ztest_device_removal_active) { spa_config_exit(spa, SCL_ALL, FTAG); mutex_exit(&ztest_vdev_lock); return; @@ -3057,16 +3058,49 @@ ztest_device_removal(ztest_ds_t *zd, uint64_t id) spa_t *spa = ztest_spa; vdev_t *vd; uint64_t guid; + int error; mutex_enter(&ztest_vdev_lock); + if (ztest_device_removal_active) { + mutex_exit(&ztest_vdev_lock); + return; + } + + /* + * Remove a random top-level vdev and wait for removal to finish. + */ spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER); vd = vdev_lookup_top(spa, ztest_random_vdev_top(spa, B_FALSE)); guid = vd->vdev_guid; spa_config_exit(spa, SCL_VDEV, FTAG); - (void) spa_vdev_remove(spa, guid, B_FALSE); + error = spa_vdev_remove(spa, guid, B_FALSE); + if (error == 0) { + ztest_device_removal_active = B_TRUE; + mutex_exit(&ztest_vdev_lock); + + while (spa->spa_vdev_removal != NULL) + txg_wait_synced(spa_get_dsl(spa), 0); + } else { + mutex_exit(&ztest_vdev_lock); + return; + } + /* + * The pool needs to be scrubbed after completing device removal. + * Failure to do so may result in checksum errors due to the + * strategy employed by ztest_fault_inject() when selecting which + * offset are redundant and can be damaged. + */ + error = spa_scan(spa, POOL_SCAN_SCRUB); + if (error == 0) { + while (dsl_scan_scrubbing(spa_get_dsl(spa))) + txg_wait_synced(spa_get_dsl(spa), 0); + } + + mutex_enter(&ztest_vdev_lock); + ztest_device_removal_active = B_FALSE; mutex_exit(&ztest_vdev_lock); } @@ -3205,7 +3239,7 @@ ztest_vdev_LUN_growth(ztest_ds_t *zd, uint64_t id) * that the metaslab_class space increased (because it decreases * when the device removal completes). */ - if (spa->spa_vdev_removal != NULL) { + if (ztest_device_removal_active) { spa_config_exit(spa, SCL_STATE, spa); mutex_exit(&ztest_vdev_lock); mutex_exit(&ztest_checkpoint_lock); @@ -4986,6 +5020,18 @@ ztest_fault_inject(ztest_ds_t *zd, uint64_t id) boolean_t islog = B_FALSE; mutex_enter(&ztest_vdev_lock); + + /* + * Device removal is in progress, fault injection must be disabled + * until it completes and the pool is scrubbed. The fault injection + * strategy for damaging blocks does not take in to account evacuated + * blocks which may have already been damaged. + */ + if (ztest_device_removal_active) { + mutex_exit(&ztest_vdev_lock); + return; + } + maxfaults = MAXFAULTS(); leaves = MAX(zs->zs_mirrors, 1) * ztest_opts.zo_raidz; mirror_save = zs->zs_mirrors; @@ -5331,6 +5377,12 @@ ztest_scrub(ztest_ds_t *zd, uint64_t id) { spa_t *spa = ztest_spa; + /* + * Scrub in progress by device removal. + */ + if (ztest_device_removal_active) + return; + (void) spa_scan(spa, POOL_SCAN_SCRUB); (void) poll(NULL, 0, 100); /* wait a moment, then force a restart */ (void) spa_scan(spa, POOL_SCAN_SCRUB); diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_pool.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_pool.c index 1eec116b9fa..c94963bf571 100644 --- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_pool.c +++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_pool.c @@ -2836,7 +2836,7 @@ zpool_vdev_attach(zpool_handle_t *zhp, case EBUSY: zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "%s is busy, " - "or pool has removing/removed vdevs"), + "or device removal is in progress"), new_disk); (void) zfs_error(hdl, EZFS_BADDEV, msg); break; diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c index 8e7616427e1..834ff2e32b8 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c @@ -2959,6 +2959,16 @@ dsl_scan_need_resilver(spa_t *spa, const dva_t *dva, size_t psize, { vdev_t *vd; + if (vd->vdev_ops == &vdev_indirect_ops) { + /* + * The indirect vdev can point to multiple + * vdevs. For simplicity, always create + * the resilver zio_t. zio_vdev_io_start() + * will bypass the child resilver i/o's if + * they are on vdevs that don't have DTL's. + */ + return (B_TRUE); + } if (DVA_GET_GANG(dva)) { /* * Gang members may be spread across multiple diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c index 35879e4e7f8..a306c0f033e 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c @@ -3596,7 +3596,7 @@ metaslab_free_impl(vdev_t *vd, uint64_t offset, uint64_t size, return; if (spa->spa_vdev_removal != NULL && - spa->spa_vdev_removal->svr_vdev == vd && + spa->spa_vdev_removal->svr_vdev_id == vd->vdev_id && vdev_is_concrete(vd)) { /* * Note: we check if the vdev is concrete because when diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c index bff343b28ec..ec06a1d108a 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c @@ -5838,8 +5838,7 @@ spa_vdev_add(spa_t *spa, nvlist_t *nvroot) for (int c = 0; c < vd->vdev_children; c++) { tvd = vd->vdev_child[c]; if (spa->spa_vdev_removal != NULL && - tvd->vdev_ashift != - spa->spa_vdev_removal->svr_vdev->vdev_ashift) { + tvd->vdev_ashift != spa->spa_max_ashift) { return (spa_vdev_exit(spa, vd, txg, EINVAL)); } /* Fail if top level vdev is raidz */ @@ -5955,10 +5954,8 @@ spa_vdev_attach(spa_t *spa, uint64_t guid, nvlist_t *nvroot, int replacing) return (spa_vdev_exit(spa, NULL, txg, error)); } - if (spa->spa_vdev_removal != NULL || - spa->spa_removing_phys.sr_prev_indirect_vdev != -1) { + if (spa->spa_vdev_removal != NULL) return (spa_vdev_exit(spa, NULL, txg, EBUSY)); - } if (oldvd == NULL) return (spa_vdev_exit(spa, NULL, txg, ENODEV)); diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_misc.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_misc.c index 1c83ec2a7be..3f1152c718c 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_misc.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_misc.c @@ -1882,9 +1882,12 @@ spa_update_dspace(spa_t *spa) * allocated twice (on the old device and the new * device). */ - vdev_t *vd = spa->spa_vdev_removal->svr_vdev; + spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER); + vdev_t *vd = + vdev_lookup_top(spa, spa->spa_vdev_removal->svr_vdev_id); spa->spa_dspace -= spa_deflate(spa) ? vd->vdev_stat.vs_dspace : vd->vdev_stat.vs_space; + spa_config_exit(spa, SCL_VDEV, FTAG); } } diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev_removal.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev_removal.h index a29ae586102..5fcd40b6e7c 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev_removal.h +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev_removal.h @@ -30,7 +30,7 @@ extern "C" { #endif typedef struct spa_vdev_removal { - vdev_t *svr_vdev; + uint64_t svr_vdev_id; uint64_t svr_max_offset_to_sync[TXG_SIZE]; /* Thread performing a vdev removal. */ kthread_t *svr_thread; diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zio.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zio.h index b0ff9598c1c..5f377734bce 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zio.h +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zio.h @@ -587,7 +587,7 @@ extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd, zio_done_func_t *done, void *priv); extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, - struct abd *data, uint64_t size, int type, zio_priority_t priority, + struct abd *data, uint64_t size, zio_type_t type, zio_priority_t priority, enum zio_flag flags, zio_done_func_t *done, void *priv); extern void zio_vdev_io_bypass(zio_t *zio); diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c index a06ecc249ae..80087a2fccc 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c @@ -988,6 +988,32 @@ vdev_top_transfer(vdev_t *svd, vdev_t *tvd) svd->vdev_stat.vs_space = 0; svd->vdev_stat.vs_dspace = 0; + /* + * State which may be set on a top-level vdev that's in the + * process of being removed. + */ + ASSERT0(tvd->vdev_indirect_config.vic_births_object); + ASSERT0(tvd->vdev_indirect_config.vic_mapping_object); + ASSERT3U(tvd->vdev_indirect_config.vic_prev_indirect_vdev, ==, -1ULL); + ASSERT3P(tvd->vdev_indirect_mapping, ==, NULL); + ASSERT3P(tvd->vdev_indirect_births, ==, NULL); + ASSERT3P(tvd->vdev_obsolete_sm, ==, NULL); + ASSERT0(tvd->vdev_removing); + tvd->vdev_removing = svd->vdev_removing; + tvd->vdev_indirect_config = svd->vdev_indirect_config; + tvd->vdev_indirect_mapping = svd->vdev_indirect_mapping; + tvd->vdev_indirect_births = svd->vdev_indirect_births; + range_tree_swap(&svd->vdev_obsolete_segments, + &tvd->vdev_obsolete_segments); + tvd->vdev_obsolete_sm = svd->vdev_obsolete_sm; + svd->vdev_indirect_config.vic_mapping_object = 0; + svd->vdev_indirect_config.vic_births_object = 0; + svd->vdev_indirect_config.vic_prev_indirect_vdev = -1ULL; + svd->vdev_indirect_mapping = NULL; + svd->vdev_indirect_births = NULL; + svd->vdev_obsolete_sm = NULL; + svd->vdev_removing = 0; + for (t = 0; t < TXG_SIZE; t++) { while ((msp = txg_list_remove(&svd->vdev_ms_list, t)) != NULL) (void) txg_list_add(&tvd->vdev_ms_list, msp, t); diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_indirect.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_indirect.c index 85d99ee36ee..f6452791c11 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_indirect.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_indirect.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include #include @@ -46,10 +47,11 @@ * "vdev_remap" operation that executes a callback on each contiguous * segment of the new location. This function is used in multiple ways: * - * - reads and repair writes to this device use the callback to create - * a child io for each mapped segment. + * - i/os to this vdev use the callback to determine where the + * data is now located, and issue child i/os for each segment's new + * location. * - * - frees and claims to this device use the callback to free or claim + * - frees and claims to this vdev use the callback to free or claim * each mapped segment. (Note that we don't actually need to claim * log blocks on indirect vdevs, because we don't allocate to * removing vdevs. However, zdb uses zio_claim() for its leak @@ -203,6 +205,94 @@ uint64_t zfs_condense_min_mapping_bytes = 128 * 1024; */ int zfs_condense_indirect_commit_entry_delay_ticks = 0; +/* + * If a split block contains more than this many segments, consider it too + * computationally expensive to check all (2^num_segments) possible + * combinations. Instead, try at most 2^_segments_max randomly-selected + * combinations. + * + * This is reasonable if only a few segment copies are damaged and the + * majority of segment copies are good. This allows all the segment copies to + * participate fairly in the reconstruction and prevents the repeated use of + * one bad copy. + */ +int zfs_reconstruct_indirect_segments_max = 10; + +/* + * The indirect_child_t represents the vdev that we will read from, when we + * need to read all copies of the data (e.g. for scrub or reconstruction). + * For plain (non-mirror) top-level vdevs (i.e. is_vdev is not a mirror), + * ic_vdev is the same as is_vdev. However, for mirror top-level vdevs, + * ic_vdev is a child of the mirror. + */ +typedef struct indirect_child { + abd_t *ic_data; + vdev_t *ic_vdev; +} indirect_child_t; + +/* + * The indirect_split_t represents one mapped segment of an i/o to the + * indirect vdev. For non-split (contiguously-mapped) blocks, there will be + * only one indirect_split_t, with is_split_offset==0 and is_size==io_size. + * For split blocks, there will be several of these. + */ +typedef struct indirect_split { + list_node_t is_node; /* link on iv_splits */ + + /* + * is_split_offset is the offset into the i/o. + * This is the sum of the previous splits' is_size's. + */ + uint64_t is_split_offset; + + vdev_t *is_vdev; /* top-level vdev */ + uint64_t is_target_offset; /* offset on is_vdev */ + uint64_t is_size; + int is_children; /* number of entries in is_child[] */ + + /* + * is_good_child is the child that we are currently using to + * attempt reconstruction. + */ + int is_good_child; + + indirect_child_t is_child[1]; /* variable-length */ +} indirect_split_t; + +/* + * The indirect_vsd_t is associated with each i/o to the indirect vdev. + * It is the "Vdev-Specific Data" in the zio_t's io_vsd. + */ +typedef struct indirect_vsd { + boolean_t iv_split_block; + boolean_t iv_reconstruct; + + list_t iv_splits; /* list of indirect_split_t's */ +} indirect_vsd_t; + +static void +vdev_indirect_map_free(zio_t *zio) +{ + indirect_vsd_t *iv = zio->io_vsd; + + indirect_split_t *is; + while ((is = list_head(&iv->iv_splits)) != NULL) { + for (int c = 0; c < is->is_children; c++) { + indirect_child_t *ic = &is->is_child[c]; + if (ic->ic_data != NULL) + abd_free(ic->ic_data); + } + list_remove(&iv->iv_splits, is); + kmem_free(is, + offsetof(indirect_split_t, is_child[is->is_children])); + } + kmem_free(iv, sizeof (*iv)); +} + +static const zio_vsd_ops_t vdev_indirect_vsd_ops = { + vdev_indirect_map_free, + zio_vsd_default_cksum_report +}; /* * Mark the given offset and size as being obsolete. */ @@ -817,12 +907,6 @@ vdev_indirect_close(vdev_t *vd) { } -/* ARGSUSED */ -static void -vdev_indirect_io_done(zio_t *zio) -{ -} - /* ARGSUSED */ static int vdev_indirect_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize, @@ -1067,41 +1151,475 @@ vdev_indirect_child_io_done(zio_t *zio) abd_put(zio->io_abd); } +/* + * This is a callback for vdev_indirect_remap() which allocates an + * indirect_split_t for each split segment and adds it to iv_splits. + */ static void -vdev_indirect_io_start_cb(uint64_t split_offset, vdev_t *vd, uint64_t offset, +vdev_indirect_gather_splits(uint64_t split_offset, vdev_t *vd, uint64_t offset, uint64_t size, void *arg) { zio_t *zio = arg; + indirect_vsd_t *iv = zio->io_vsd; ASSERT3P(vd, !=, NULL); if (vd->vdev_ops == &vdev_indirect_ops) return; - zio_nowait(zio_vdev_child_io(zio, NULL, vd, offset, - abd_get_offset(zio->io_abd, split_offset), - size, zio->io_type, zio->io_priority, - 0, vdev_indirect_child_io_done, zio)); + int n = 1; + if (vd->vdev_ops == &vdev_mirror_ops) + n = vd->vdev_children; + + indirect_split_t *is = + kmem_zalloc(offsetof(indirect_split_t, is_child[n]), KM_SLEEP); + + is->is_children = n; + is->is_size = size; + is->is_split_offset = split_offset; + is->is_target_offset = offset; + is->is_vdev = vd; + + /* + * Note that we only consider multiple copies of the data for + * *mirror* vdevs. We don't for "replacing" or "spare" vdevs, even + * though they use the same ops as mirror, because there's only one + * "good" copy under the replacing/spare. + */ + if (vd->vdev_ops == &vdev_mirror_ops) { + for (int i = 0; i < n; i++) { + is->is_child[i].ic_vdev = vd->vdev_child[i]; + } + } else { + is->is_child[0].ic_vdev = vd; + } + + list_insert_tail(&iv->iv_splits, is); +} + +static void +vdev_indirect_read_split_done(zio_t *zio) +{ + indirect_child_t *ic = zio->io_private; + + if (zio->io_error != 0) { + /* + * Clear ic_data to indicate that we do not have data for this + * child. + */ + abd_free(ic->ic_data); + ic->ic_data = NULL; + } +} + +/* + * Issue reads for all copies (mirror children) of all splits. + */ +static void +vdev_indirect_read_all(zio_t *zio) +{ + indirect_vsd_t *iv = zio->io_vsd; + + for (indirect_split_t *is = list_head(&iv->iv_splits); + is != NULL; is = list_next(&iv->iv_splits, is)) { + for (int i = 0; i < is->is_children; i++) { + indirect_child_t *ic = &is->is_child[i]; + + if (!vdev_readable(ic->ic_vdev)) + continue; + + /* + * Note, we may read from a child whose DTL + * indicates that the data may not be present here. + * While this might result in a few i/os that will + * likely return incorrect data, it simplifies the + * code since we can treat scrub and resilver + * identically. (The incorrect data will be + * detected and ignored when we verify the + * checksum.) + */ + + ic->ic_data = abd_alloc_sametype(zio->io_abd, + is->is_size); + + zio_nowait(zio_vdev_child_io(zio, NULL, + ic->ic_vdev, is->is_target_offset, ic->ic_data, + is->is_size, zio->io_type, zio->io_priority, 0, + vdev_indirect_read_split_done, ic)); + } + } + iv->iv_reconstruct = B_TRUE; } static void vdev_indirect_io_start(zio_t *zio) { spa_t *spa = zio->io_spa; + indirect_vsd_t *iv = kmem_zalloc(sizeof (*iv), KM_SLEEP); + list_create(&iv->iv_splits, + sizeof (indirect_split_t), offsetof(indirect_split_t, is_node)); + + zio->io_vsd = iv; + zio->io_vsd_ops = &vdev_indirect_vsd_ops; ASSERT(spa_config_held(spa, SCL_ALL, RW_READER) != 0); if (zio->io_type != ZIO_TYPE_READ) { ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE); - ASSERT((zio->io_flags & - (ZIO_FLAG_SELF_HEAL | ZIO_FLAG_INDUCE_DAMAGE)) != 0); + /* + * Note: this code can handle other kinds of writes, + * but we don't expect them. + */ + ASSERT((zio->io_flags & (ZIO_FLAG_SELF_HEAL | + ZIO_FLAG_RESILVER | ZIO_FLAG_INDUCE_DAMAGE)) != 0); } vdev_indirect_remap(zio->io_vd, zio->io_offset, zio->io_size, - vdev_indirect_io_start_cb, zio); + vdev_indirect_gather_splits, zio); + + indirect_split_t *first = list_head(&iv->iv_splits); + if (first->is_size == zio->io_size) { + /* + * This is not a split block; we are pointing to the entire + * data, which will checksum the same as the original data. + * Pass the BP down so that the child i/o can verify the + * checksum, and try a different location if available + * (e.g. on a mirror). + * + * While this special case could be handled the same as the + * general (split block) case, doing it this way ensures + * that the vast majority of blocks on indirect vdevs + * (which are not split) are handled identically to blocks + * on non-indirect vdevs. This allows us to be less strict + * about performance in the general (but rare) case. + */ + ASSERT0(first->is_split_offset); + ASSERT3P(list_next(&iv->iv_splits, first), ==, NULL); + zio_nowait(zio_vdev_child_io(zio, zio->io_bp, + first->is_vdev, first->is_target_offset, + abd_get_offset(zio->io_abd, 0), + zio->io_size, zio->io_type, zio->io_priority, 0, + vdev_indirect_child_io_done, zio)); + } else { + iv->iv_split_block = B_TRUE; + if (zio->io_flags & (ZIO_FLAG_SCRUB | ZIO_FLAG_RESILVER)) { + /* + * Read all copies. Note that for simplicity, + * we don't bother consulting the DTL in the + * resilver case. + */ + vdev_indirect_read_all(zio); + } else { + /* + * Read one copy of each split segment, from the + * top-level vdev. Since we don't know the + * checksum of each split individually, the child + * zio can't ensure that we get the right data. + * E.g. if it's a mirror, it will just read from a + * random (healthy) leaf vdev. We have to verify + * the checksum in vdev_indirect_io_done(). + */ + for (indirect_split_t *is = list_head(&iv->iv_splits); + is != NULL; is = list_next(&iv->iv_splits, is)) { + zio_nowait(zio_vdev_child_io(zio, NULL, + is->is_vdev, is->is_target_offset, + abd_get_offset(zio->io_abd, + is->is_split_offset), + is->is_size, zio->io_type, + zio->io_priority, 0, + vdev_indirect_child_io_done, zio)); + } + } + } zio_execute(zio); } +/* + * Report a checksum error for a child. + */ +static void +vdev_indirect_checksum_error(zio_t *zio, + indirect_split_t *is, indirect_child_t *ic) +{ + vdev_t *vd = ic->ic_vdev; + + if (zio->io_flags & ZIO_FLAG_SPECULATIVE) + return; + + mutex_enter(&vd->vdev_stat_lock); + vd->vdev_stat.vs_checksum_errors++; + mutex_exit(&vd->vdev_stat_lock); + + zio_bad_cksum_t zbc = { 0 }; + void *bad_buf = abd_borrow_buf_copy(ic->ic_data, is->is_size); + abd_t *good_abd = is->is_child[is->is_good_child].ic_data; + void *good_buf = abd_borrow_buf_copy(good_abd, is->is_size); + zfs_ereport_post_checksum(zio->io_spa, vd, zio, + is->is_target_offset, is->is_size, good_buf, bad_buf, &zbc); + abd_return_buf(ic->ic_data, bad_buf, is->is_size); + abd_return_buf(good_abd, good_buf, is->is_size); +} + +/* + * Issue repair i/os for any incorrect copies. We do this by comparing + * each split segment's correct data (is_good_child's ic_data) with each + * other copy of the data. If they differ, then we overwrite the bad data + * with the good copy. Note that we do this without regard for the DTL's, + * which simplifies this code and also issues the optimal number of writes + * (based on which copies actually read bad data, as opposed to which we + * think might be wrong). For the same reason, we always use + * ZIO_FLAG_SELF_HEAL, to bypass the DTL check in zio_vdev_io_start(). + */ +static void +vdev_indirect_repair(zio_t *zio) +{ + indirect_vsd_t *iv = zio->io_vsd; + + enum zio_flag flags = ZIO_FLAG_IO_REPAIR; + + if (!(zio->io_flags & (ZIO_FLAG_SCRUB | ZIO_FLAG_RESILVER))) + flags |= ZIO_FLAG_SELF_HEAL; + + if (!spa_writeable(zio->io_spa)) + return; + + for (indirect_split_t *is = list_head(&iv->iv_splits); + is != NULL; is = list_next(&iv->iv_splits, is)) { + indirect_child_t *good_child = &is->is_child[is->is_good_child]; + + for (int c = 0; c < is->is_children; c++) { + indirect_child_t *ic = &is->is_child[c]; + if (ic == good_child) + continue; + if (ic->ic_data == NULL) + continue; + if (abd_cmp(good_child->ic_data, ic->ic_data, + is->is_size) == 0) + continue; + + zio_nowait(zio_vdev_child_io(zio, NULL, + ic->ic_vdev, is->is_target_offset, + good_child->ic_data, is->is_size, + ZIO_TYPE_WRITE, ZIO_PRIORITY_ASYNC_WRITE, + ZIO_FLAG_IO_REPAIR | ZIO_FLAG_SELF_HEAL, + NULL, NULL)); + + vdev_indirect_checksum_error(zio, is, ic); + } + } +} + +/* + * Report checksum errors on all children that we read from. + */ +static void +vdev_indirect_all_checksum_errors(zio_t *zio) +{ + indirect_vsd_t *iv = zio->io_vsd; + + if (zio->io_flags & ZIO_FLAG_SPECULATIVE) + return; + + for (indirect_split_t *is = list_head(&iv->iv_splits); + is != NULL; is = list_next(&iv->iv_splits, is)) { + for (int c = 0; c < is->is_children; c++) { + indirect_child_t *ic = &is->is_child[c]; + + if (ic->ic_data == NULL) + continue; + + vdev_t *vd = ic->ic_vdev; + + mutex_enter(&vd->vdev_stat_lock); + vd->vdev_stat.vs_checksum_errors++; + mutex_exit(&vd->vdev_stat_lock); + + zfs_ereport_post_checksum(zio->io_spa, vd, zio, + is->is_target_offset, is->is_size, + NULL, NULL, NULL); + } + } +} + +/* + * This function is called when we have read all copies of the data and need + * to try to find a combination of copies that gives us the right checksum. + * + * If we pointed to any mirror vdevs, this effectively does the job of the + * mirror. The mirror vdev code can't do its own job because we don't know + * the checksum of each split segment individually. We have to try every + * combination of copies of split segments, until we find one that checksums + * correctly. (Or until we have tried all combinations, or have tried + * 2^zfs_reconstruct_indirect_segments_max combinations. In these cases we + * set io_error to ECKSUM to propagate the error up to the user.) + * + * For example, if we have 3 segments in the split, + * and each points to a 2-way mirror, we will have the following pieces of + * data: + * + * | mirror child + * split | [0] [1] + * ======|===================== + * A | data_A_0 data_A_1 + * B | data_B_0 data_B_1 + * C | data_C_0 data_C_1 + * + * We will try the following (mirror children)^(number of splits) (2^3=8) + * combinations, which is similar to bitwise-little-endian counting in + * binary. In general each "digit" corresponds to a split segment, and the + * base of each digit is is_children, which can be different for each + * digit. + * + * "low bit" "high bit" + * v v + * data_A_0 data_B_0 data_C_0 + * data_A_1 data_B_0 data_C_0 + * data_A_0 data_B_1 data_C_0 + * data_A_1 data_B_1 data_C_0 + * data_A_0 data_B_0 data_C_1 + * data_A_1 data_B_0 data_C_1 + * data_A_0 data_B_1 data_C_1 + * data_A_1 data_B_1 data_C_1 + * + * Note that the split segments may be on the same or different top-level + * vdevs. In either case, we try lots of combinations (see + * zfs_reconstruct_indirect_segments_max). This ensures that if a mirror has + * small silent errors on all of its children, we can still reconstruct the + * correct data, as long as those errors are at sufficiently-separated + * offsets (specifically, separated by the largest block size - default of + * 128KB, but up to 16MB). + */ +static void +vdev_indirect_reconstruct_io_done(zio_t *zio) +{ + indirect_vsd_t *iv = zio->io_vsd; + uint64_t attempts = 0; + uint64_t attempts_max = 1ULL << zfs_reconstruct_indirect_segments_max; + int segments = 0; + + for (indirect_split_t *is = list_head(&iv->iv_splits); + is != NULL; is = list_next(&iv->iv_splits, is)) + segments++; + + for (;;) { + /* copy data from splits to main zio */ + int ret; + for (indirect_split_t *is = list_head(&iv->iv_splits); + is != NULL; is = list_next(&iv->iv_splits, is)) { + + /* + * If this child failed, its ic_data will be NULL. + * Skip this combination. + */ + if (is->is_child[is->is_good_child].ic_data == NULL) { + ret = EIO; + goto next; + } + + abd_copy_off(zio->io_abd, + is->is_child[is->is_good_child].ic_data, + is->is_split_offset, 0, is->is_size); + } + + /* See if this checksum matches. */ + zio_bad_cksum_t zbc; + ret = zio_checksum_error(zio, &zbc); + if (ret == 0) { + /* Found a matching checksum. Issue repair i/os. */ + vdev_indirect_repair(zio); + zio_checksum_verified(zio); + return; + } + + /* + * Checksum failed; try a different combination of split + * children. + */ + boolean_t more; +next: + more = B_FALSE; + if (segments <= zfs_reconstruct_indirect_segments_max) { + /* + * There are relatively few segments, so + * deterministically check all combinations. We do + * this by by adding one to the first split's + * good_child. If it overflows, then "carry over" to + * the next split (like counting in base is_children, + * but each digit can have a different base). + */ + for (indirect_split_t *is = list_head(&iv->iv_splits); + is != NULL; is = list_next(&iv->iv_splits, is)) { + is->is_good_child++; + if (is->is_good_child < is->is_children) { + more = B_TRUE; + break; + } + is->is_good_child = 0; + } + } else if (++attempts < attempts_max) { + /* + * There are too many combinations to try all of them + * in a reasonable amount of time, so try a fixed + * number of random combinations, after which we'll + * consider the block unrecoverable. + */ + for (indirect_split_t *is = list_head(&iv->iv_splits); + is != NULL; is = list_next(&iv->iv_splits, is)) { + is->is_good_child = + spa_get_random(is->is_children); + } + more = B_TRUE; + } + if (!more) { + /* All combinations failed. */ + zio->io_error = ret; + vdev_indirect_all_checksum_errors(zio); + zio_checksum_verified(zio); + return; + } + } +} + +static void +vdev_indirect_io_done(zio_t *zio) +{ + indirect_vsd_t *iv = zio->io_vsd; + + if (iv->iv_reconstruct) { + /* + * We have read all copies of the data (e.g. from mirrors), + * either because this was a scrub/resilver, or because the + * one-copy read didn't checksum correctly. + */ + vdev_indirect_reconstruct_io_done(zio); + return; + } + + if (!iv->iv_split_block) { + /* + * This was not a split block, so we passed the BP down, + * and the checksum was handled by the (one) child zio. + */ + return; + } + + zio_bad_cksum_t zbc; + int ret = zio_checksum_error(zio, &zbc); + if (ret == 0) { + zio_checksum_verified(zio); + return; + } + + /* + * The checksum didn't match. Read all copies of all splits, and + * then we will try to reconstruct. The next time + * vdev_indirect_io_done() is called, iv_reconstruct will be set. + */ + vdev_indirect_read_all(zio); + + zio_vdev_io_redone(zio); +} + vdev_ops_t vdev_indirect_ops = { vdev_indirect_open, vdev_indirect_close, 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 index 60cb7aa96fc..e23acf73fbc 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_mirror.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_mirror.c @@ -24,7 +24,7 @@ */ /* - * Copyright (c) 2012, 2015 by Delphix. All rights reserved. + * Copyright (c) 2012, 2018 by Delphix. All rights reserved. */ #include @@ -516,13 +516,16 @@ vdev_mirror_io_start(zio_t *zio) } if (zio->io_type == ZIO_TYPE_READ) { - if ((zio->io_flags & ZIO_FLAG_SCRUB) && !mm->mm_resilvering && + if (zio->io_bp != NULL && + (zio->io_flags & ZIO_FLAG_SCRUB) && !mm->mm_resilvering && mm->mm_children > 1) { /* - * For scrubbing reads 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 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]; @@ -677,7 +680,21 @@ vdev_mirror_io_done(zio_t *zio) 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; diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_removal.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_removal.c index b1c53287dae..44391755b1e 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_removal.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_removal.c @@ -83,18 +83,12 @@ typedef struct vdev_copy_arg { kmutex_t vca_lock; } vdev_copy_arg_t; -typedef struct vdev_copy_seg_arg { - vdev_copy_arg_t *vcsa_copy_arg; - uint64_t vcsa_txg; - dva_t *vcsa_dest_dva; - blkptr_t *vcsa_dest_bp; -} vdev_copy_seg_arg_t; - /* - * The maximum amount of allowed data we're allowed to copy from a device - * at a time when removing it. + * The maximum amount of memory we can use for outstanding i/o while + * doing a device removal. This determines how much i/o we can have + * in flight concurrently. */ -int zfs_remove_max_copy_bytes = 8 * 1024 * 1024; +int zfs_remove_max_copy_bytes = 64 * 1024 * 1024; /* * The largest contiguous segment that we will attempt to allocate when @@ -176,7 +170,7 @@ spa_vdev_removal_create(vdev_t *vd) mutex_init(&svr->svr_lock, NULL, MUTEX_DEFAULT, NULL); cv_init(&svr->svr_cv, NULL, CV_DEFAULT, NULL); svr->svr_allocd_segs = range_tree_create(NULL, NULL); - svr->svr_vdev = vd; + svr->svr_vdev_id = vd->vdev_id; for (int i = 0; i < TXG_SIZE; i++) { svr->svr_frees[i] = range_tree_create(NULL, NULL); @@ -218,9 +212,10 @@ spa_vdev_removal_destroy(spa_vdev_removal_t *svr) static void vdev_remove_initiate_sync(void *arg, dmu_tx_t *tx) { - vdev_t *vd = arg; + int vdev_id = (uintptr_t)arg; + spa_t *spa = dmu_tx_pool(tx)->dp_spa; + vdev_t *vd = vdev_lookup_top(spa, vdev_id); vdev_indirect_config_t *vic = &vd->vdev_indirect_config; - spa_t *spa = vd->vdev_spa; objset_t *mos = spa->spa_dsl_pool->dp_meta_objset; spa_vdev_removal_t *svr = NULL; uint64_t txg = dmu_tx_get_txg(tx); @@ -342,7 +337,7 @@ vdev_remove_initiate_sync(void *arg, dmu_tx_t *tx) ASSERT3P(spa->spa_vdev_removal, ==, NULL); spa->spa_vdev_removal = svr; svr->svr_thread = thread_create(NULL, 0, - spa_vdev_remove_thread, vd, 0, &p0, TS_RUN, minclsyspri); + spa_vdev_remove_thread, spa, 0, &p0, TS_RUN, minclsyspri); } /* @@ -384,21 +379,24 @@ spa_remove_init(spa_t *spa) spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); vdev_t *vd = vdev_lookup_top(spa, spa->spa_removing_phys.sr_removing_vdev); - spa_config_exit(spa, SCL_STATE, FTAG); - if (vd == NULL) + if (vd == NULL) { + spa_config_exit(spa, SCL_STATE, FTAG); return (EINVAL); + } vdev_indirect_config_t *vic = &vd->vdev_indirect_config; ASSERT(vdev_is_concrete(vd)); spa_vdev_removal_t *svr = spa_vdev_removal_create(vd); - ASSERT(svr->svr_vdev->vdev_removing); + ASSERT3U(svr->svr_vdev_id, ==, vd->vdev_id); + ASSERT(vd->vdev_removing); vd->vdev_indirect_mapping = vdev_indirect_mapping_open( spa->spa_meta_objset, vic->vic_mapping_object); vd->vdev_indirect_births = vdev_indirect_births_open( spa->spa_meta_objset, vic->vic_births_object); + spa_config_exit(spa, SCL_STATE, FTAG); spa->spa_vdev_removal = svr; } @@ -451,15 +449,8 @@ spa_restart_removal(spa_t *spa) if (!spa_writeable(spa)) return; - vdev_t *vd = svr->svr_vdev; - vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping; - - ASSERT3P(vd, !=, NULL); - ASSERT(vd->vdev_removing); - - zfs_dbgmsg("restarting removal of %llu at count=%llu", - vd->vdev_id, vdev_indirect_mapping_num_entries(vim)); - svr->svr_thread = thread_create(NULL, 0, spa_vdev_remove_thread, vd, + zfs_dbgmsg("restarting removal of %llu", svr->svr_vdev_id); + svr->svr_thread = thread_create(NULL, 0, spa_vdev_remove_thread, spa, 0, &p0, TS_RUN, minclsyspri); } @@ -480,7 +471,7 @@ free_from_removing_vdev(vdev_t *vd, uint64_t offset, uint64_t size) ASSERT(vd->vdev_indirect_config.vic_mapping_object != 0); ASSERT3U(vd->vdev_indirect_config.vic_mapping_object, ==, vdev_indirect_mapping_object(vim)); - ASSERT3P(vd, ==, svr->svr_vdev); + ASSERT3U(vd->vdev_id, ==, svr->svr_vdev_id); mutex_enter(&svr->svr_lock); @@ -663,7 +654,7 @@ spa_finish_removal(spa_t *spa, dsl_scan_state_t state, dmu_tx_t *tx) if (state == DSS_FINISHED) { spa_removing_phys_t *srp = &spa->spa_removing_phys; - vdev_t *vd = svr->svr_vdev; + vdev_t *vd = vdev_lookup_top(spa, svr->svr_vdev_id); vdev_indirect_config_t *vic = &vd->vdev_indirect_config; if (srp->sr_prev_indirect_vdev != UINT64_MAX) { @@ -706,7 +697,7 @@ vdev_mapping_sync(void *arg, dmu_tx_t *tx) { spa_vdev_removal_t *svr = arg; spa_t *spa = dmu_tx_pool(tx)->dp_spa; - vdev_t *vd = svr->svr_vdev; + vdev_t *vd = vdev_lookup_top(spa, svr->svr_vdev_id); vdev_indirect_config_t *vic = &vd->vdev_indirect_config; uint64_t txg = dmu_tx_get_txg(tx); vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping; @@ -734,64 +725,128 @@ vdev_mapping_sync(void *arg, dmu_tx_t *tx) spa_sync_removing_state(spa, tx); } +/* + * All reads and writes associated with a call to spa_vdev_copy_segment() + * are done. + */ +static void +spa_vdev_copy_nullzio_done(zio_t *zio) +{ + spa_config_exit(zio->io_spa, SCL_STATE, zio->io_spa); +} + +/* + * The write of the new location is done. + */ static void spa_vdev_copy_segment_write_done(zio_t *zio) { - vdev_copy_seg_arg_t *vcsa = zio->io_private; - vdev_copy_arg_t *vca = vcsa->vcsa_copy_arg; - spa_config_exit(zio->io_spa, SCL_STATE, FTAG); + vdev_copy_arg_t *vca = zio->io_private; + abd_free(zio->io_abd); mutex_enter(&vca->vca_lock); vca->vca_outstanding_bytes -= zio->io_size; cv_signal(&vca->vca_cv); mutex_exit(&vca->vca_lock); - - ASSERT0(zio->io_error); - kmem_free(vcsa->vcsa_dest_bp, sizeof (blkptr_t)); - kmem_free(vcsa, sizeof (vdev_copy_seg_arg_t)); } +/* + * The read of the old location is done. The parent zio is the write to + * the new location. Allow it to start. + */ static void spa_vdev_copy_segment_read_done(zio_t *zio) { - vdev_copy_seg_arg_t *vcsa = zio->io_private; - dva_t *dest_dva = vcsa->vcsa_dest_dva; - uint64_t txg = vcsa->vcsa_txg; - spa_t *spa = zio->io_spa; - vdev_t *dest_vd = vdev_lookup_top(spa, DVA_GET_VDEV(dest_dva)); - blkptr_t *bp = NULL; - dva_t *dva = NULL; - uint64_t size = zio->io_size; - - ASSERT3P(dest_vd, !=, NULL); - ASSERT0(zio->io_error); - - vcsa->vcsa_dest_bp = kmem_alloc(sizeof (blkptr_t), KM_SLEEP); - bp = vcsa->vcsa_dest_bp; - dva = bp->blk_dva; - - BP_ZERO(bp); - - /* initialize with dest_dva */ - bcopy(dest_dva, dva, sizeof (dva_t)); - BP_SET_BIRTH(bp, TXG_INITIAL, TXG_INITIAL); - - BP_SET_LSIZE(bp, size); - BP_SET_PSIZE(bp, size); - BP_SET_COMPRESS(bp, ZIO_COMPRESS_OFF); - BP_SET_CHECKSUM(bp, ZIO_CHECKSUM_OFF); - BP_SET_TYPE(bp, DMU_OT_NONE); - BP_SET_LEVEL(bp, 0); - BP_SET_DEDUP(bp, 0); - BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER); - - zio_nowait(zio_rewrite(spa->spa_txg_zio[txg & TXG_MASK], spa, - txg, bp, zio->io_abd, size, - spa_vdev_copy_segment_write_done, vcsa, - ZIO_PRIORITY_REMOVAL, 0, NULL)); + zio_nowait(zio_unique_parent(zio)); } +/* + * If the old and new vdevs are mirrors, we will read both sides of the old + * mirror, and write each copy to the corresponding side of the new mirror. + * If the old and new vdevs have a different number of children, we will do + * this as best as possible. Since we aren't verifying checksums, this + * ensures that as long as there's a good copy of the data, we'll have a + * good copy after the removal, even if there's silent damage to one side + * of the mirror. If we're removing a mirror that has some silent damage, + * we'll have exactly the same damage in the new location (assuming that + * the new location is also a mirror). + * + * We accomplish this by creating a tree of zio_t's, with as many writes as + * there are "children" of the new vdev (a non-redundant vdev counts as one + * child, a 2-way mirror has 2 children, etc). Each write has an associated + * read from a child of the old vdev. Typically there will be the same + * number of children of the old and new vdevs. However, if there are more + * children of the new vdev, some child(ren) of the old vdev will be issued + * multiple reads. If there are more children of the old vdev, some copies + * will be dropped. + * + * For example, the tree of zio_t's for a 2-way mirror is: + * + * null + * / \ + * write(new vdev, child 0) write(new vdev, child 1) + * | | + * read(old vdev, child 0) read(old vdev, child 1) + * + * Child zio's complete before their parents complete. However, zio's + * created with zio_vdev_child_io() may be issued before their children + * complete. In this case we need to make sure that the children (reads) + * complete before the parents (writes) are *issued*. We do this by not + * calling zio_nowait() on each write until its corresponding read has + * completed. + * + * The spa_config_lock must be held while zio's created by + * zio_vdev_child_io() are in progress, to ensure that the vdev tree does + * not change (e.g. due to a concurrent "zpool attach/detach"). The "null" + * zio is needed to release the spa_config_lock after all the reads and + * writes complete. (Note that we can't grab the config lock for each read, + * because it is not reentrant - we could deadlock with a thread waiting + * for a write lock.) + */ +static void +spa_vdev_copy_one_child(vdev_copy_arg_t *vca, zio_t *nzio, + vdev_t *source_vd, uint64_t source_offset, + vdev_t *dest_child_vd, uint64_t dest_offset, int dest_id, uint64_t size) +{ + ASSERT3U(spa_config_held(nzio->io_spa, SCL_ALL, RW_READER), !=, 0); + + mutex_enter(&vca->vca_lock); + vca->vca_outstanding_bytes += size; + mutex_exit(&vca->vca_lock); + + abd_t *abd = abd_alloc_for_io(size, B_FALSE); + + vdev_t *source_child_vd; + if (source_vd->vdev_ops == &vdev_mirror_ops && dest_id != -1) { + /* + * Source and dest are both mirrors. Copy from the same + * child id as we are copying to (wrapping around if there + * are more dest children than source children). + */ + source_child_vd = + source_vd->vdev_child[dest_id % source_vd->vdev_children]; + } else { + source_child_vd = source_vd; + } + + zio_t *write_zio = zio_vdev_child_io(nzio, NULL, + dest_child_vd, dest_offset, abd, size, + ZIO_TYPE_WRITE, ZIO_PRIORITY_REMOVAL, + ZIO_FLAG_CANFAIL, + spa_vdev_copy_segment_write_done, vca); + + zio_nowait(zio_vdev_child_io(write_zio, NULL, + source_child_vd, source_offset, abd, size, + ZIO_TYPE_READ, ZIO_PRIORITY_REMOVAL, + ZIO_FLAG_CANFAIL, + spa_vdev_copy_segment_read_done, vca)); +} + +/* + * Allocate a new location for this segment, and create the zio_t's to + * read from the old location and write to the new location. + */ static int spa_vdev_copy_segment(vdev_t *vd, uint64_t start, uint64_t size, uint64_t txg, vdev_copy_arg_t *vca, zio_alloc_list_t *zal) @@ -800,10 +855,7 @@ spa_vdev_copy_segment(vdev_t *vd, uint64_t start, uint64_t size, uint64_t txg, spa_t *spa = vd->vdev_spa; spa_vdev_removal_t *svr = spa->spa_vdev_removal; vdev_indirect_mapping_entry_t *entry; - vdev_copy_seg_arg_t *private; dva_t dst = { 0 }; - blkptr_t blk, *bp = &blk; - dva_t *dva = bp->blk_dva; ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); @@ -827,51 +879,28 @@ spa_vdev_copy_segment(vdev_t *vd, uint64_t start, uint64_t size, uint64_t txg, */ ASSERT3U(DVA_GET_ASIZE(&dst), ==, size); - mutex_enter(&vca->vca_lock); - vca->vca_outstanding_bytes += size; - mutex_exit(&vca->vca_lock); - entry = kmem_zalloc(sizeof (vdev_indirect_mapping_entry_t), KM_SLEEP); DVA_MAPPING_SET_SRC_OFFSET(&entry->vime_mapping, start); entry->vime_mapping.vimep_dst = dst; - private = kmem_alloc(sizeof (vdev_copy_seg_arg_t), KM_SLEEP); - private->vcsa_dest_dva = &entry->vime_mapping.vimep_dst; - private->vcsa_txg = txg; - private->vcsa_copy_arg = vca; - /* - * This lock is eventually released by the donefunc for the - * zio_write_phys that finishes copying the data. + * See comment before spa_vdev_copy_one_child(). */ - spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); - - /* - * Do logical I/O, letting the redundancy vdevs (like mirror) - * handle their own I/O instead of duplicating that code here. - */ - BP_ZERO(bp); - - DVA_SET_VDEV(&dva[0], vd->vdev_id); - DVA_SET_OFFSET(&dva[0], start); - DVA_SET_GANG(&dva[0], 0); - DVA_SET_ASIZE(&dva[0], vdev_psize_to_asize(vd, size)); - - BP_SET_BIRTH(bp, TXG_INITIAL, TXG_INITIAL); - - BP_SET_LSIZE(bp, size); - BP_SET_PSIZE(bp, size); - BP_SET_COMPRESS(bp, ZIO_COMPRESS_OFF); - BP_SET_CHECKSUM(bp, ZIO_CHECKSUM_OFF); - BP_SET_TYPE(bp, DMU_OT_NONE); - BP_SET_LEVEL(bp, 0); - BP_SET_DEDUP(bp, 0); - BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER); - - zio_nowait(zio_read(spa->spa_txg_zio[txg & TXG_MASK], spa, - bp, abd_alloc_for_io(size, B_FALSE), size, - spa_vdev_copy_segment_read_done, private, - ZIO_PRIORITY_REMOVAL, 0, NULL)); + spa_config_enter(spa, SCL_STATE, spa, RW_READER); + zio_t *nzio = zio_null(spa->spa_txg_zio[txg & TXG_MASK], spa, NULL, + spa_vdev_copy_nullzio_done, NULL, 0); + vdev_t *dest_vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dst)); + if (dest_vd->vdev_ops == &vdev_mirror_ops) { + for (int i = 0; i < dest_vd->vdev_children; i++) { + vdev_t *child = dest_vd->vdev_child[i]; + spa_vdev_copy_one_child(vca, nzio, vd, start, + child, DVA_GET_OFFSET(&dst), i, size); + } + } else { + spa_vdev_copy_one_child(vca, nzio, vd, start, + dest_vd, DVA_GET_OFFSET(&dst), -1, size); + } + zio_nowait(nzio); list_insert_tail(&svr->svr_new_segments[txg & TXG_MASK], entry); ASSERT3U(start + size, <=, vd->vdev_ms_count << vd->vdev_ms_shift); @@ -889,8 +918,8 @@ static void vdev_remove_complete_sync(void *arg, dmu_tx_t *tx) { spa_vdev_removal_t *svr = arg; - vdev_t *vd = svr->svr_vdev; - spa_t *spa = vd->vdev_spa; + spa_t *spa = dmu_tx_pool(tx)->dp_spa; + vdev_t *vd = vdev_lookup_top(spa, svr->svr_vdev_id); ASSERT3P(vd->vdev_ops, ==, &vdev_indirect_ops); @@ -918,37 +947,6 @@ vdev_remove_complete_sync(void *arg, dmu_tx_t *tx) "%s vdev %llu", spa_name(spa), vd->vdev_id); } -static void -vdev_indirect_state_transfer(vdev_t *ivd, vdev_t *vd) -{ - ivd->vdev_indirect_config = vd->vdev_indirect_config; - - ASSERT3P(ivd->vdev_indirect_mapping, ==, NULL); - ASSERT(vd->vdev_indirect_mapping != NULL); - ivd->vdev_indirect_mapping = vd->vdev_indirect_mapping; - vd->vdev_indirect_mapping = NULL; - - ASSERT3P(ivd->vdev_indirect_births, ==, NULL); - ASSERT(vd->vdev_indirect_births != NULL); - ivd->vdev_indirect_births = vd->vdev_indirect_births; - vd->vdev_indirect_births = NULL; - - ASSERT0(range_tree_space(vd->vdev_obsolete_segments)); - ASSERT0(range_tree_space(ivd->vdev_obsolete_segments)); - - if (vd->vdev_obsolete_sm != NULL) { - ASSERT3U(ivd->vdev_asize, ==, vd->vdev_asize); - - /* - * We cannot use space_map_{open,close} because we hold all - * the config locks as writer. - */ - ASSERT3P(ivd->vdev_obsolete_sm, ==, NULL); - ivd->vdev_obsolete_sm = vd->vdev_obsolete_sm; - vd->vdev_obsolete_sm = NULL; - } -} - static void vdev_remove_enlist_zaps(vdev_t *vd, nvlist_t *zlist) { @@ -984,17 +982,13 @@ vdev_remove_replace_with_indirect(vdev_t *vd, uint64_t txg) vdev_remove_enlist_zaps(vd, svr->svr_zaplist); ivd = vdev_add_parent(vd, &vdev_indirect_ops); + ivd->vdev_removing = 0; vd->vdev_leaf_zap = 0; vdev_remove_child(ivd, vd); vdev_compact_children(ivd); - vdev_indirect_state_transfer(ivd, vd); - - svr->svr_vdev = ivd; - - ASSERT(!ivd->vdev_removing); ASSERT(!list_link_active(&vd->vdev_state_dirty_node)); tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg); @@ -1017,9 +1011,8 @@ vdev_remove_replace_with_indirect(vdev_t *vd, uint64_t txg) * context by the removal thread after we have copied all vdev's data. */ static void -vdev_remove_complete(vdev_t *vd) +vdev_remove_complete(spa_t *spa) { - spa_t *spa = vd->vdev_spa; uint64_t txg; /* @@ -1027,8 +1020,12 @@ vdev_remove_complete(vdev_t *vd) * vdev_metaslab_fini() */ txg_wait_synced(spa->spa_dsl_pool, 0); - txg = spa_vdev_enter(spa); + vdev_t *vd = vdev_lookup_top(spa, spa->spa_vdev_removal->svr_vdev_id); + + sysevent_t *ev = spa_event_create(spa, vd, NULL, + ESC_ZFS_VDEV_REMOVE_DEV); + zfs_dbgmsg("finishing device removal for vdev %llu in txg %llu", vd->vdev_id, txg); @@ -1048,6 +1045,10 @@ vdev_remove_complete(vdev_t *vd) /* * We now release the locks, allowing spa_sync to run and finish the * removal via vdev_remove_complete_sync in syncing context. + * + * Note that we hold on to the vdev_t that has been replaced. Since + * it isn't part of the vdev tree any longer, it can't be concurrently + * manipulated, even while we don't have the config lock. */ (void) spa_vdev_exit(spa, NULL, txg, 0); @@ -1069,6 +1070,8 @@ vdev_remove_complete(vdev_t *vd) */ vdev_config_dirty(spa->spa_root_vdev); (void) spa_vdev_exit(spa, vd, txg, 0); + + spa_event_post(ev); } /* @@ -1079,7 +1082,7 @@ vdev_remove_complete(vdev_t *vd) * this size again this txg. */ static void -spa_vdev_copy_impl(spa_vdev_removal_t *svr, vdev_copy_arg_t *vca, +spa_vdev_copy_impl(vdev_t *vd, spa_vdev_removal_t *svr, vdev_copy_arg_t *vca, uint64_t *max_alloc, dmu_tx_t *tx) { uint64_t txg = dmu_tx_get_txg(tx); @@ -1118,7 +1121,7 @@ spa_vdev_copy_impl(spa_vdev_removal_t *svr, vdev_copy_arg_t *vca, while (length > 0) { uint64_t mylen = MIN(length, thismax); - int error = spa_vdev_copy_segment(svr->svr_vdev, + int error = spa_vdev_copy_segment(vd, offset, mylen, txg, vca, &zal); if (error == ENOSPC) { @@ -1176,12 +1179,14 @@ spa_vdev_copy_impl(spa_vdev_removal_t *svr, vdev_copy_arg_t *vca, static void spa_vdev_remove_thread(void *arg) { - vdev_t *vd = arg; - spa_t *spa = vd->vdev_spa; + spa_t *spa = arg; spa_vdev_removal_t *svr = spa->spa_vdev_removal; vdev_copy_arg_t vca; uint64_t max_alloc = zfs_remove_max_segment; uint64_t last_txg = 0; + + spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER); + vdev_t *vd = vdev_lookup_top(spa, svr->svr_vdev_id); vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping; uint64_t start_offset = vdev_indirect_mapping_max_offset(vim); @@ -1189,7 +1194,6 @@ spa_vdev_remove_thread(void *arg) ASSERT(vdev_is_concrete(vd)); ASSERT(vd->vdev_removing); ASSERT(vd->vdev_indirect_config.vic_mapping_object != 0); - ASSERT3P(svr->svr_vdev, ==, vd); ASSERT(vim != NULL); mutex_init(&vca.vca_lock, NULL, MUTEX_DEFAULT, NULL); @@ -1270,6 +1274,17 @@ spa_vdev_remove_thread(void *arg) mutex_exit(&svr->svr_lock); + /* + * We need to periodically drop the config lock so that + * writers can get in. Additionally, we can't wait + * for a txg to sync while holding a config lock + * (since a waiting writer could cause a 3-way deadlock + * with the sync thread, which also gets a config + * lock for reader). So we can't hold the config lock + * while calling dmu_tx_assign(). + */ + spa_config_exit(spa, SCL_CONFIG, FTAG); + /* * This delay will pause the removal around the point * specified by zfs_remove_max_bytes_pause. We do this @@ -1296,11 +1311,19 @@ spa_vdev_remove_thread(void *arg) VERIFY0(dmu_tx_assign(tx, TXG_WAIT)); uint64_t txg = dmu_tx_get_txg(tx); + /* + * Reacquire the vdev_config lock. The vdev_t + * that we're removing may have changed, e.g. due + * to a vdev_attach or vdev_detach. + */ + spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER); + vd = vdev_lookup_top(spa, svr->svr_vdev_id); + if (txg != last_txg) max_alloc = zfs_remove_max_segment; last_txg = txg; - spa_vdev_copy_impl(svr, &vca, &max_alloc, tx); + spa_vdev_copy_impl(vd, svr, &vca, &max_alloc, tx); dmu_tx_commit(tx); mutex_enter(&svr->svr_lock); @@ -1308,6 +1331,9 @@ spa_vdev_remove_thread(void *arg) } mutex_exit(&svr->svr_lock); + + spa_config_exit(spa, SCL_CONFIG, FTAG); + /* * Wait for all copies to finish before cleaning up the vca. */ @@ -1325,7 +1351,7 @@ spa_vdev_remove_thread(void *arg) mutex_exit(&svr->svr_lock); } else { ASSERT0(range_tree_space(svr->svr_allocd_segs)); - vdev_remove_complete(vd); + vdev_remove_complete(spa); } thread_exit(); } @@ -1367,7 +1393,7 @@ spa_vdev_remove_cancel_sync(void *arg, dmu_tx_t *tx) { spa_t *spa = dmu_tx_pool(tx)->dp_spa; spa_vdev_removal_t *svr = spa->spa_vdev_removal; - vdev_t *vd = svr->svr_vdev; + vdev_t *vd = vdev_lookup_top(spa, svr->svr_vdev_id); vdev_indirect_config_t *vic = &vd->vdev_indirect_config; vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping; objset_t *mos = spa->spa_meta_objset; @@ -1440,8 +1466,11 @@ spa_vdev_remove_cancel_sync(void *arg, dmu_tx_t *tx) * because we have not allocated mappings for it yet. */ uint64_t syncd = vdev_indirect_mapping_max_offset(vim); - range_tree_clear(svr->svr_allocd_segs, syncd, - msp->ms_sm->sm_start + msp->ms_sm->sm_size - syncd); + uint64_t sm_end = msp->ms_sm->sm_start + + msp->ms_sm->sm_size; + if (sm_end > syncd) + range_tree_clear(svr->svr_allocd_segs, + syncd, sm_end - syncd); mutex_exit(&svr->svr_lock); } @@ -1502,7 +1531,7 @@ spa_vdev_remove_cancel(spa_t *spa) if (spa->spa_vdev_removal == NULL) return (ESRCH); - uint64_t vdid = spa->spa_vdev_removal->svr_vdev->vdev_id; + uint64_t vdid = spa->spa_vdev_removal->svr_vdev_id; int error = dsl_sync_task(spa->spa_name, spa_vdev_remove_cancel_check, spa_vdev_remove_cancel_sync, NULL, 0, @@ -1813,7 +1842,7 @@ spa_vdev_remove_top(vdev_t *vd, uint64_t *txg) dmu_tx_t *tx = dmu_tx_create_assigned(spa->spa_dsl_pool, *txg); dsl_sync_task_nowait(spa->spa_dsl_pool, vdev_remove_initiate_sync, - vd, 0, ZFS_SPACE_CHECK_NONE, tx); + (void *)(uintptr_t)vd->vdev_id, 0, ZFS_SPACE_CHECK_NONE, tx); dmu_tx_commit(tx); return (0); diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c index 9776317426d..e302bab60c1 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c @@ -1150,17 +1150,6 @@ zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset, ASSERT((flags & ZIO_FLAG_OPTIONAL) || (flags & ZIO_FLAG_IO_REPAIR) || done != NULL); - /* - * In the common case, where the parent zio was to a normal vdev, - * the child zio must be to a child vdev of that vdev. Otherwise, - * the child zio must be to a top-level vdev. - */ - if (pio->io_vd != NULL && pio->io_vd->vdev_ops != &vdev_indirect_ops) { - ASSERT3P(vd->vdev_parent, ==, pio->io_vd); - } else { - ASSERT3P(vd, ==, vd->vdev_top); - } - if (type == ZIO_TYPE_READ && bp != NULL) { /* * If we have the bp, then the child should perform the @@ -1224,7 +1213,7 @@ zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset, zio_t * zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, abd_t *data, uint64_t size, - int type, zio_priority_t priority, enum zio_flag flags, + zio_type_t type, zio_priority_t priority, enum zio_flag flags, zio_done_func_t *done, void *private) { zio_t *zio; @@ -3204,9 +3193,13 @@ zio_vdev_io_start(zio_t *zio) ASSERT(spa->spa_trust_config); if (zio->io_vd->vdev_removing) { + /* + * Note: the code can handle other kinds of writes, + * but we don't expect them. + */ ASSERT(zio->io_flags & (ZIO_FLAG_PHYSICAL | ZIO_FLAG_SELF_HEAL | - ZIO_FLAG_INDUCE_DAMAGE)); + ZIO_FLAG_RESILVER | ZIO_FLAG_INDUCE_DAMAGE)); } } @@ -3272,18 +3265,37 @@ zio_vdev_io_start(zio_t *zio) * If this is a repair I/O, and there's no self-healing involved -- * that is, we're just resilvering what we expect to resilver -- * then don't do the I/O unless zio's txg is actually in vd's DTL. - * This prevents spurious resilvering with nested replication. - * For example, given a mirror of mirrors, (A+B)+(C+D), if only - * A is out of date, we'll read from C+D, then use the data to - * resilver A+B -- but we don't actually want to resilver B, just A. - * The top-level mirror has no way to know this, so instead we just - * discard unnecessary repairs as we work our way down the vdev tree. - * The same logic applies to any form of nested replication: - * ditto + mirror, RAID-Z + replacing, etc. This covers them all. + * This prevents spurious resilvering. + * + * There are a few ways that we can end up creating these spurious + * resilver i/os: + * + * 1. A resilver i/o will be issued if any DVA in the BP has a + * dirty DTL. The mirror code will issue resilver writes to + * each DVA, including the one(s) that are not on vdevs with dirty + * DTLs. + * + * 2. With nested replication, which happens when we have a + * "replacing" or "spare" vdev that's a child of a mirror or raidz. + * For example, given mirror(replacing(A+B), C), it's likely that + * only A is out of date (it's the new device). In this case, we'll + * read from C, then use the data to resilver A+B -- but we don't + * actually want to resilver B, just A. The top-level mirror has no + * way to know this, so instead we just discard unnecessary repairs + * as we work our way down the vdev tree. + * + * 3. ZTEST also creates mirrors of mirrors, mirrors of raidz, etc. + * The same logic applies to any form of nested replication: ditto + * + mirror, RAID-Z + replacing, etc. + * + * However, indirect vdevs point off to other vdevs which may have + * DTL's, so we never bypass them. The child i/os on concrete vdevs + * will be properly bypassed instead. */ if ((zio->io_flags & ZIO_FLAG_IO_REPAIR) && !(zio->io_flags & ZIO_FLAG_SELF_HEAL) && zio->io_txg != 0 && /* not a delegated i/o */ + vd->vdev_ops != &vdev_indirect_ops && !vdev_dtl_contains(vd, DTL_PARTIAL, zio->io_txg, 1)) { ASSERT(zio->io_type == ZIO_TYPE_WRITE); zio_vdev_io_bypass(zio); -- 2.45.0