diff options
Diffstat (limited to 'module/zfs/dsl_destroy.c')
| -rw-r--r-- | module/zfs/dsl_destroy.c | 940 |
1 files changed, 940 insertions, 0 deletions
diff --git a/module/zfs/dsl_destroy.c b/module/zfs/dsl_destroy.c new file mode 100644 index 000000000..1fb3859ac --- /dev/null +++ b/module/zfs/dsl_destroy.c @@ -0,0 +1,940 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2012 by Delphix. All rights reserved. + */ + +#include <sys/zfs_context.h> +#include <sys/dsl_userhold.h> +#include <sys/dsl_dataset.h> +#include <sys/dsl_synctask.h> +#include <sys/dmu_tx.h> +#include <sys/dsl_pool.h> +#include <sys/dsl_dir.h> +#include <sys/dmu_traverse.h> +#include <sys/dsl_scan.h> +#include <sys/dmu_objset.h> +#include <sys/zap.h> +#include <sys/zfeature.h> +#include <sys/zfs_ioctl.h> +#include <sys/dsl_deleg.h> + +typedef struct dmu_snapshots_destroy_arg { + nvlist_t *dsda_snaps; + nvlist_t *dsda_successful_snaps; + boolean_t dsda_defer; + nvlist_t *dsda_errlist; +} dmu_snapshots_destroy_arg_t; + +/* + * ds must be owned. + */ +static int +dsl_destroy_snapshot_check_impl(dsl_dataset_t *ds, boolean_t defer) +{ + if (!dsl_dataset_is_snapshot(ds)) + return (EINVAL); + + if (dsl_dataset_long_held(ds)) + return (EBUSY); + + /* + * Only allow deferred destroy on pools that support it. + * NOTE: deferred destroy is only supported on snapshots. + */ + if (defer) { + if (spa_version(ds->ds_dir->dd_pool->dp_spa) < + SPA_VERSION_USERREFS) + return (ENOTSUP); + return (0); + } + + /* + * If this snapshot has an elevated user reference count, + * we can't destroy it yet. + */ + if (ds->ds_userrefs > 0) + return (EBUSY); + + /* + * Can't delete a branch point. + */ + if (ds->ds_phys->ds_num_children > 1) + return (EEXIST); + + return (0); +} + +static int +dsl_destroy_snapshot_check(void *arg, dmu_tx_t *tx) +{ + dmu_snapshots_destroy_arg_t *dsda = arg; + dsl_pool_t *dp = dmu_tx_pool(tx); + nvpair_t *pair; + int error = 0; + + if (!dmu_tx_is_syncing(tx)) + return (0); + + for (pair = nvlist_next_nvpair(dsda->dsda_snaps, NULL); + pair != NULL; pair = nvlist_next_nvpair(dsda->dsda_snaps, pair)) { + dsl_dataset_t *ds; + + error = dsl_dataset_hold(dp, nvpair_name(pair), + FTAG, &ds); + + /* + * If the snapshot does not exist, silently ignore it + * (it's "already destroyed"). + */ + if (error == ENOENT) + continue; + + if (error == 0) { + error = dsl_destroy_snapshot_check_impl(ds, + dsda->dsda_defer); + dsl_dataset_rele(ds, FTAG); + } + + if (error == 0) { + fnvlist_add_boolean(dsda->dsda_successful_snaps, + nvpair_name(pair)); + } else { + fnvlist_add_int32(dsda->dsda_errlist, + nvpair_name(pair), error); + } + } + + pair = nvlist_next_nvpair(dsda->dsda_errlist, NULL); + if (pair != NULL) + return (fnvpair_value_int32(pair)); + return (0); +} + +struct process_old_arg { + dsl_dataset_t *ds; + dsl_dataset_t *ds_prev; + boolean_t after_branch_point; + zio_t *pio; + uint64_t used, comp, uncomp; +}; + +static int +process_old_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx) +{ + struct process_old_arg *poa = arg; + dsl_pool_t *dp = poa->ds->ds_dir->dd_pool; + + if (bp->blk_birth <= poa->ds->ds_phys->ds_prev_snap_txg) { + dsl_deadlist_insert(&poa->ds->ds_deadlist, bp, tx); + if (poa->ds_prev && !poa->after_branch_point && + bp->blk_birth > + poa->ds_prev->ds_phys->ds_prev_snap_txg) { + poa->ds_prev->ds_phys->ds_unique_bytes += + bp_get_dsize_sync(dp->dp_spa, bp); + } + } else { + poa->used += bp_get_dsize_sync(dp->dp_spa, bp); + poa->comp += BP_GET_PSIZE(bp); + poa->uncomp += BP_GET_UCSIZE(bp); + dsl_free_sync(poa->pio, dp, tx->tx_txg, bp); + } + return (0); +} + +static void +process_old_deadlist(dsl_dataset_t *ds, dsl_dataset_t *ds_prev, + dsl_dataset_t *ds_next, boolean_t after_branch_point, dmu_tx_t *tx) +{ + struct process_old_arg poa = { 0 }; + dsl_pool_t *dp = ds->ds_dir->dd_pool; + objset_t *mos = dp->dp_meta_objset; + uint64_t deadlist_obj; + + ASSERT(ds->ds_deadlist.dl_oldfmt); + ASSERT(ds_next->ds_deadlist.dl_oldfmt); + + poa.ds = ds; + poa.ds_prev = ds_prev; + poa.after_branch_point = after_branch_point; + poa.pio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); + VERIFY0(bpobj_iterate(&ds_next->ds_deadlist.dl_bpobj, + process_old_cb, &poa, tx)); + VERIFY0(zio_wait(poa.pio)); + ASSERT3U(poa.used, ==, ds->ds_phys->ds_unique_bytes); + + /* change snapused */ + dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP, + -poa.used, -poa.comp, -poa.uncomp, tx); + + /* swap next's deadlist to our deadlist */ + dsl_deadlist_close(&ds->ds_deadlist); + dsl_deadlist_close(&ds_next->ds_deadlist); + deadlist_obj = ds->ds_phys->ds_deadlist_obj; + ds->ds_phys->ds_deadlist_obj = ds_next->ds_phys->ds_deadlist_obj; + ds_next->ds_phys->ds_deadlist_obj = deadlist_obj; + dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj); + dsl_deadlist_open(&ds_next->ds_deadlist, mos, + ds_next->ds_phys->ds_deadlist_obj); +} + +static void +dsl_dataset_remove_clones_key(dsl_dataset_t *ds, uint64_t mintxg, dmu_tx_t *tx) +{ + objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset; + zap_cursor_t zc; + zap_attribute_t za; + + /* + * If it is the old version, dd_clones doesn't exist so we can't + * find the clones, but dsl_deadlist_remove_key() is a no-op so it + * doesn't matter. + */ + if (ds->ds_dir->dd_phys->dd_clones == 0) + return; + + for (zap_cursor_init(&zc, mos, ds->ds_dir->dd_phys->dd_clones); + zap_cursor_retrieve(&zc, &za) == 0; + zap_cursor_advance(&zc)) { + dsl_dataset_t *clone; + + VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool, + za.za_first_integer, FTAG, &clone)); + if (clone->ds_dir->dd_origin_txg > mintxg) { + dsl_deadlist_remove_key(&clone->ds_deadlist, + mintxg, tx); + dsl_dataset_remove_clones_key(clone, mintxg, tx); + } + dsl_dataset_rele(clone, FTAG); + } + zap_cursor_fini(&zc); +} + +void +dsl_destroy_snapshot_sync_impl(dsl_dataset_t *ds, boolean_t defer, dmu_tx_t *tx) +{ +#ifdef ZFS_DEBUG + int err; +#endif + int after_branch_point = FALSE; + dsl_pool_t *dp = ds->ds_dir->dd_pool; + objset_t *mos = dp->dp_meta_objset; + dsl_dataset_t *ds_prev = NULL; + uint64_t obj, old_unique, used = 0, comp = 0, uncomp = 0; + dsl_dataset_t *ds_next, *ds_head, *hds; + + + ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); + ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg); + ASSERT(refcount_is_zero(&ds->ds_longholds)); + + if (defer && + (ds->ds_userrefs > 0 || ds->ds_phys->ds_num_children > 1)) { + ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS); + dmu_buf_will_dirty(ds->ds_dbuf, tx); + ds->ds_phys->ds_flags |= DS_FLAG_DEFER_DESTROY; + spa_history_log_internal_ds(ds, "defer_destroy", tx, ""); + return; + } + + ASSERT3U(ds->ds_phys->ds_num_children, <=, 1); + + /* We need to log before removing it from the namespace. */ + spa_history_log_internal_ds(ds, "destroy", tx, ""); + + dsl_scan_ds_destroyed(ds, tx); + + obj = ds->ds_object; + + if (ds->ds_phys->ds_prev_snap_obj != 0) { + ASSERT3P(ds->ds_prev, ==, NULL); + VERIFY0(dsl_dataset_hold_obj(dp, + ds->ds_phys->ds_prev_snap_obj, FTAG, &ds_prev)); + after_branch_point = + (ds_prev->ds_phys->ds_next_snap_obj != obj); + + dmu_buf_will_dirty(ds_prev->ds_dbuf, tx); + if (after_branch_point && + ds_prev->ds_phys->ds_next_clones_obj != 0) { + dsl_dataset_remove_from_next_clones(ds_prev, obj, tx); + if (ds->ds_phys->ds_next_snap_obj != 0) { + VERIFY0(zap_add_int(mos, + ds_prev->ds_phys->ds_next_clones_obj, + ds->ds_phys->ds_next_snap_obj, tx)); + } + } + if (!after_branch_point) { + ds_prev->ds_phys->ds_next_snap_obj = + ds->ds_phys->ds_next_snap_obj; + } + } + + VERIFY0(dsl_dataset_hold_obj(dp, + ds->ds_phys->ds_next_snap_obj, FTAG, &ds_next)); + ASSERT3U(ds_next->ds_phys->ds_prev_snap_obj, ==, obj); + + old_unique = ds_next->ds_phys->ds_unique_bytes; + + dmu_buf_will_dirty(ds_next->ds_dbuf, tx); + ds_next->ds_phys->ds_prev_snap_obj = + ds->ds_phys->ds_prev_snap_obj; + ds_next->ds_phys->ds_prev_snap_txg = + ds->ds_phys->ds_prev_snap_txg; + ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==, + ds_prev ? ds_prev->ds_phys->ds_creation_txg : 0); + + if (ds_next->ds_deadlist.dl_oldfmt) { + process_old_deadlist(ds, ds_prev, ds_next, + after_branch_point, tx); + } else { + /* Adjust prev's unique space. */ + if (ds_prev && !after_branch_point) { + dsl_deadlist_space_range(&ds_next->ds_deadlist, + ds_prev->ds_phys->ds_prev_snap_txg, + ds->ds_phys->ds_prev_snap_txg, + &used, &comp, &uncomp); + ds_prev->ds_phys->ds_unique_bytes += used; + } + + /* Adjust snapused. */ + dsl_deadlist_space_range(&ds_next->ds_deadlist, + ds->ds_phys->ds_prev_snap_txg, UINT64_MAX, + &used, &comp, &uncomp); + dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP, + -used, -comp, -uncomp, tx); + + /* Move blocks to be freed to pool's free list. */ + dsl_deadlist_move_bpobj(&ds_next->ds_deadlist, + &dp->dp_free_bpobj, ds->ds_phys->ds_prev_snap_txg, + tx); + dsl_dir_diduse_space(tx->tx_pool->dp_free_dir, + DD_USED_HEAD, used, comp, uncomp, tx); + + /* Merge our deadlist into next's and free it. */ + dsl_deadlist_merge(&ds_next->ds_deadlist, + ds->ds_phys->ds_deadlist_obj, tx); + } + dsl_deadlist_close(&ds->ds_deadlist); + dsl_deadlist_free(mos, ds->ds_phys->ds_deadlist_obj, tx); + dmu_buf_will_dirty(ds->ds_dbuf, tx); + ds->ds_phys->ds_deadlist_obj = 0; + + /* Collapse range in clone heads */ + dsl_dataset_remove_clones_key(ds, + ds->ds_phys->ds_creation_txg, tx); + + if (dsl_dataset_is_snapshot(ds_next)) { + dsl_dataset_t *ds_nextnext; + + /* + * Update next's unique to include blocks which + * were previously shared by only this snapshot + * and it. Those blocks will be born after the + * prev snap and before this snap, and will have + * died after the next snap and before the one + * after that (ie. be on the snap after next's + * deadlist). + */ + VERIFY0(dsl_dataset_hold_obj(dp, + ds_next->ds_phys->ds_next_snap_obj, FTAG, &ds_nextnext)); + dsl_deadlist_space_range(&ds_nextnext->ds_deadlist, + ds->ds_phys->ds_prev_snap_txg, + ds->ds_phys->ds_creation_txg, + &used, &comp, &uncomp); + ds_next->ds_phys->ds_unique_bytes += used; + dsl_dataset_rele(ds_nextnext, FTAG); + ASSERT3P(ds_next->ds_prev, ==, NULL); + + /* Collapse range in this head. */ + VERIFY0(dsl_dataset_hold_obj(dp, + ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &hds)); + dsl_deadlist_remove_key(&hds->ds_deadlist, + ds->ds_phys->ds_creation_txg, tx); + dsl_dataset_rele(hds, FTAG); + + } else { + ASSERT3P(ds_next->ds_prev, ==, ds); + dsl_dataset_rele(ds_next->ds_prev, ds_next); + ds_next->ds_prev = NULL; + if (ds_prev) { + VERIFY0(dsl_dataset_hold_obj(dp, + ds->ds_phys->ds_prev_snap_obj, + ds_next, &ds_next->ds_prev)); + } + + dsl_dataset_recalc_head_uniq(ds_next); + + /* + * Reduce the amount of our unconsumed refreservation + * being charged to our parent by the amount of + * new unique data we have gained. + */ + if (old_unique < ds_next->ds_reserved) { + int64_t mrsdelta; + uint64_t new_unique = + ds_next->ds_phys->ds_unique_bytes; + + ASSERT(old_unique <= new_unique); + mrsdelta = MIN(new_unique - old_unique, + ds_next->ds_reserved - old_unique); + dsl_dir_diduse_space(ds->ds_dir, + DD_USED_REFRSRV, -mrsdelta, 0, 0, tx); + } + } + dsl_dataset_rele(ds_next, FTAG); + + /* + * This must be done after the dsl_traverse(), because it will + * re-open the objset. + */ + if (ds->ds_objset) { + dmu_objset_evict(ds->ds_objset); + ds->ds_objset = NULL; + } + + /* remove from snapshot namespace */ + ASSERT(ds->ds_phys->ds_snapnames_zapobj == 0); + VERIFY0(dsl_dataset_hold_obj(dp, + ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ds_head)); + VERIFY0(dsl_dataset_get_snapname(ds)); +#ifdef ZFS_DEBUG + { + uint64_t val; + + err = dsl_dataset_snap_lookup(ds_head, + ds->ds_snapname, &val); + ASSERT0(err); + ASSERT3U(val, ==, obj); + } +#endif + VERIFY0(dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx)); + dsl_dataset_rele(ds_head, FTAG); + + if (ds_prev != NULL) + dsl_dataset_rele(ds_prev, FTAG); + + spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx); + + if (ds->ds_phys->ds_next_clones_obj != 0) { + ASSERTV(uint64_t count); + ASSERT0(zap_count(mos, + ds->ds_phys->ds_next_clones_obj, &count) && count == 0); + VERIFY0(dmu_object_free(mos, + ds->ds_phys->ds_next_clones_obj, tx)); + } + if (ds->ds_phys->ds_props_obj != 0) + VERIFY0(zap_destroy(mos, ds->ds_phys->ds_props_obj, tx)); + if (ds->ds_phys->ds_userrefs_obj != 0) + VERIFY0(zap_destroy(mos, ds->ds_phys->ds_userrefs_obj, tx)); + dsl_dir_rele(ds->ds_dir, ds); + ds->ds_dir = NULL; + VERIFY0(dmu_object_free(mos, obj, tx)); +} + +static void +dsl_destroy_snapshot_sync(void *arg, dmu_tx_t *tx) +{ + dmu_snapshots_destroy_arg_t *dsda = arg; + dsl_pool_t *dp = dmu_tx_pool(tx); + nvpair_t *pair; + + for (pair = nvlist_next_nvpair(dsda->dsda_successful_snaps, NULL); + pair != NULL; + pair = nvlist_next_nvpair(dsda->dsda_successful_snaps, pair)) { + dsl_dataset_t *ds; + + VERIFY0(dsl_dataset_hold(dp, nvpair_name(pair), FTAG, &ds)); + + dsl_destroy_snapshot_sync_impl(ds, dsda->dsda_defer, tx); + dsl_dataset_rele(ds, FTAG); + } +} + +/* + * The semantics of this function are described in the comment above + * lzc_destroy_snaps(). To summarize: + * + * The snapshots must all be in the same pool. + * + * Snapshots that don't exist will be silently ignored (considered to be + * "already deleted"). + * + * On success, all snaps will be destroyed and this will return 0. + * On failure, no snaps will be destroyed, the errlist will be filled in, + * and this will return an errno. + */ +int +dsl_destroy_snapshots_nvl(nvlist_t *snaps, boolean_t defer, + nvlist_t *errlist) +{ + dmu_snapshots_destroy_arg_t dsda; + int error; + nvpair_t *pair; + + pair = nvlist_next_nvpair(snaps, NULL); + if (pair == NULL) + return (0); + + dsda.dsda_snaps = snaps; + VERIFY0(nvlist_alloc(&dsda.dsda_successful_snaps, NV_UNIQUE_NAME, KM_PUSHPAGE)); + dsda.dsda_defer = defer; + dsda.dsda_errlist = errlist; + + error = dsl_sync_task(nvpair_name(pair), + dsl_destroy_snapshot_check, dsl_destroy_snapshot_sync, + &dsda, 0); + fnvlist_free(dsda.dsda_successful_snaps); + + return (error); +} + +int +dsl_destroy_snapshot(const char *name, boolean_t defer) +{ + int error; + nvlist_t *nvl; + nvlist_t *errlist; + + VERIFY0(nvlist_alloc(&nvl, NV_UNIQUE_NAME, KM_PUSHPAGE)); + VERIFY0(nvlist_alloc(&errlist, NV_UNIQUE_NAME, KM_PUSHPAGE)); + + fnvlist_add_boolean(nvl, name); + error = dsl_destroy_snapshots_nvl(nvl, defer, errlist); + fnvlist_free(errlist); + fnvlist_free(nvl); + return (error); +} + +struct killarg { + dsl_dataset_t *ds; + dmu_tx_t *tx; +}; + +/* ARGSUSED */ +static int +kill_blkptr(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, + const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg) +{ + struct killarg *ka = arg; + dmu_tx_t *tx = ka->tx; + + if (bp == NULL) + return (0); + + if (zb->zb_level == ZB_ZIL_LEVEL) { + ASSERT(zilog != NULL); + /* + * It's a block in the intent log. It has no + * accounting, so just free it. + */ + dsl_free(ka->tx->tx_pool, ka->tx->tx_txg, bp); + } else { + ASSERT(zilog == NULL); + ASSERT3U(bp->blk_birth, >, ka->ds->ds_phys->ds_prev_snap_txg); + (void) dsl_dataset_block_kill(ka->ds, bp, tx, B_FALSE); + } + + return (0); +} + +static void +old_synchronous_dataset_destroy(dsl_dataset_t *ds, dmu_tx_t *tx) +{ + struct killarg ka; + + /* + * Free everything that we point to (that's born after + * the previous snapshot, if we are a clone) + * + * NB: this should be very quick, because we already + * freed all the objects in open context. + */ + ka.ds = ds; + ka.tx = tx; + VERIFY0(traverse_dataset(ds, + ds->ds_phys->ds_prev_snap_txg, TRAVERSE_POST, + kill_blkptr, &ka)); + ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) || ds->ds_phys->ds_unique_bytes == 0); +} + +typedef struct dsl_destroy_head_arg { + const char *ddha_name; +} dsl_destroy_head_arg_t; + +int +dsl_destroy_head_check_impl(dsl_dataset_t *ds, int expected_holds) +{ + int error; + uint64_t count; + objset_t *mos; + + if (dsl_dataset_is_snapshot(ds)) + return (EINVAL); + + if (refcount_count(&ds->ds_longholds) != expected_holds) + return (EBUSY); + + mos = ds->ds_dir->dd_pool->dp_meta_objset; + + /* + * Can't delete a head dataset if there are snapshots of it. + * (Except if the only snapshots are from the branch we cloned + * from.) + */ + if (ds->ds_prev != NULL && + ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) + return (EBUSY); + + /* + * Can't delete if there are children of this fs. + */ + error = zap_count(mos, + ds->ds_dir->dd_phys->dd_child_dir_zapobj, &count); + if (error != 0) + return (error); + if (count != 0) + return (EEXIST); + + if (dsl_dir_is_clone(ds->ds_dir) && DS_IS_DEFER_DESTROY(ds->ds_prev) && + ds->ds_prev->ds_phys->ds_num_children == 2 && + ds->ds_prev->ds_userrefs == 0) { + /* We need to remove the origin snapshot as well. */ + if (!refcount_is_zero(&ds->ds_prev->ds_longholds)) + return (EBUSY); + } + return (0); +} + +static int +dsl_destroy_head_check(void *arg, dmu_tx_t *tx) +{ + dsl_destroy_head_arg_t *ddha = arg; + dsl_pool_t *dp = dmu_tx_pool(tx); + dsl_dataset_t *ds; + int error; + + error = dsl_dataset_hold(dp, ddha->ddha_name, FTAG, &ds); + if (error != 0) + return (error); + + error = dsl_destroy_head_check_impl(ds, 0); + dsl_dataset_rele(ds, FTAG); + return (error); +} + +static void +dsl_dir_destroy_sync(uint64_t ddobj, dmu_tx_t *tx) +{ + dsl_dir_t *dd; + dsl_pool_t *dp = dmu_tx_pool(tx); + objset_t *mos = dp->dp_meta_objset; + dd_used_t t; + + ASSERT(RRW_WRITE_HELD(&dmu_tx_pool(tx)->dp_config_rwlock)); + + VERIFY0(dsl_dir_hold_obj(dp, ddobj, NULL, FTAG, &dd)); + + ASSERT0(dd->dd_phys->dd_head_dataset_obj); + + /* + * Remove our reservation. The impl() routine avoids setting the + * actual property, which would require the (already destroyed) ds. + */ + dsl_dir_set_reservation_sync_impl(dd, 0, tx); + + ASSERT0(dd->dd_phys->dd_used_bytes); + ASSERT0(dd->dd_phys->dd_reserved); + for (t = 0; t < DD_USED_NUM; t++) + ASSERT0(dd->dd_phys->dd_used_breakdown[t]); + + VERIFY0(zap_destroy(mos, dd->dd_phys->dd_child_dir_zapobj, tx)); + VERIFY0(zap_destroy(mos, dd->dd_phys->dd_props_zapobj, tx)); + VERIFY0(dsl_deleg_destroy(mos, dd->dd_phys->dd_deleg_zapobj, tx)); + VERIFY0(zap_remove(mos, + dd->dd_parent->dd_phys->dd_child_dir_zapobj, dd->dd_myname, tx)); + + dsl_dir_rele(dd, FTAG); + VERIFY0(dmu_object_free(mos, ddobj, tx)); +} + +void +dsl_destroy_head_sync_impl(dsl_dataset_t *ds, dmu_tx_t *tx) +{ + dsl_pool_t *dp = dmu_tx_pool(tx); + objset_t *mos = dp->dp_meta_objset; + uint64_t obj, ddobj, prevobj = 0; + boolean_t rmorigin; + zfeature_info_t *async_destroy; + objset_t *os; + + ASSERT3U(ds->ds_phys->ds_num_children, <=, 1); + ASSERT(ds->ds_prev == NULL || + ds->ds_prev->ds_phys->ds_next_snap_obj != ds->ds_object); + ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg); + ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); + + /* We need to log before removing it from the namespace. */ + spa_history_log_internal_ds(ds, "destroy", tx, ""); + + rmorigin = (dsl_dir_is_clone(ds->ds_dir) && + DS_IS_DEFER_DESTROY(ds->ds_prev) && + ds->ds_prev->ds_phys->ds_num_children == 2 && + ds->ds_prev->ds_userrefs == 0); + + /* Remove our reservation */ + if (ds->ds_reserved != 0) { + dsl_dataset_set_refreservation_sync_impl(ds, + (ZPROP_SRC_NONE | ZPROP_SRC_LOCAL | ZPROP_SRC_RECEIVED), + 0, tx); + ASSERT0(ds->ds_reserved); + } + + dsl_scan_ds_destroyed(ds, tx); + + obj = ds->ds_object; + + if (ds->ds_phys->ds_prev_snap_obj != 0) { + /* This is a clone */ + ASSERT(ds->ds_prev != NULL); + ASSERT3U(ds->ds_prev->ds_phys->ds_next_snap_obj, !=, obj); + ASSERT0(ds->ds_phys->ds_next_snap_obj); + + dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); + if (ds->ds_prev->ds_phys->ds_next_clones_obj != 0) { + dsl_dataset_remove_from_next_clones(ds->ds_prev, + obj, tx); + } + + ASSERT3U(ds->ds_prev->ds_phys->ds_num_children, >, 1); + ds->ds_prev->ds_phys->ds_num_children--; + } + + async_destroy = + &spa_feature_table[SPA_FEATURE_ASYNC_DESTROY]; + + /* + * Destroy the deadlist. Unless it's a clone, the + * deadlist should be empty. (If it's a clone, it's + * safe to ignore the deadlist contents.) + */ + dsl_deadlist_close(&ds->ds_deadlist); + dsl_deadlist_free(mos, ds->ds_phys->ds_deadlist_obj, tx); + dmu_buf_will_dirty(ds->ds_dbuf, tx); + ds->ds_phys->ds_deadlist_obj = 0; + + VERIFY0(dmu_objset_from_ds(ds, &os)); + + if (!spa_feature_is_enabled(dp->dp_spa, async_destroy)) { + old_synchronous_dataset_destroy(ds, tx); + } else { + /* + * Move the bptree into the pool's list of trees to + * clean up and update space accounting information. + */ + uint64_t used, comp, uncomp; + + zil_destroy_sync(dmu_objset_zil(os), tx); + + if (!spa_feature_is_active(dp->dp_spa, async_destroy)) { + spa_feature_incr(dp->dp_spa, async_destroy, tx); + dp->dp_bptree_obj = bptree_alloc(mos, tx); + VERIFY0(zap_add(mos, + DMU_POOL_DIRECTORY_OBJECT, + DMU_POOL_BPTREE_OBJ, sizeof (uint64_t), 1, + &dp->dp_bptree_obj, tx)); + } + + used = ds->ds_dir->dd_phys->dd_used_bytes; + comp = ds->ds_dir->dd_phys->dd_compressed_bytes; + uncomp = ds->ds_dir->dd_phys->dd_uncompressed_bytes; + + ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) || + ds->ds_phys->ds_unique_bytes == used); + + bptree_add(mos, dp->dp_bptree_obj, + &ds->ds_phys->ds_bp, ds->ds_phys->ds_prev_snap_txg, + used, comp, uncomp, tx); + dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, + -used, -comp, -uncomp, tx); + dsl_dir_diduse_space(dp->dp_free_dir, DD_USED_HEAD, + used, comp, uncomp, tx); + } + + if (ds->ds_prev != NULL) { + if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) { + VERIFY0(zap_remove_int(mos, + ds->ds_prev->ds_dir->dd_phys->dd_clones, + ds->ds_object, tx)); + } + prevobj = ds->ds_prev->ds_object; + dsl_dataset_rele(ds->ds_prev, ds); + ds->ds_prev = NULL; + } + + /* + * This must be done after the dsl_traverse(), because it will + * re-open the objset. + */ + if (ds->ds_objset) { + dmu_objset_evict(ds->ds_objset); + ds->ds_objset = NULL; + } + + /* Erase the link in the dir */ + dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx); + ds->ds_dir->dd_phys->dd_head_dataset_obj = 0; + ddobj = ds->ds_dir->dd_object; + ASSERT(ds->ds_phys->ds_snapnames_zapobj != 0); + VERIFY0(zap_destroy(mos, ds->ds_phys->ds_snapnames_zapobj, tx)); + + spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx); + + ASSERT0(ds->ds_phys->ds_next_clones_obj); + ASSERT0(ds->ds_phys->ds_props_obj); + ASSERT0(ds->ds_phys->ds_userrefs_obj); + dsl_dir_rele(ds->ds_dir, ds); + ds->ds_dir = NULL; + VERIFY0(dmu_object_free(mos, obj, tx)); + + dsl_dir_destroy_sync(ddobj, tx); + + if (rmorigin) { + dsl_dataset_t *prev; + VERIFY0(dsl_dataset_hold_obj(dp, prevobj, FTAG, &prev)); + dsl_destroy_snapshot_sync_impl(prev, B_FALSE, tx); + dsl_dataset_rele(prev, FTAG); + } +} + +static void +dsl_destroy_head_sync(void *arg, dmu_tx_t *tx) +{ + dsl_destroy_head_arg_t *ddha = arg; + dsl_pool_t *dp = dmu_tx_pool(tx); + dsl_dataset_t *ds; + + VERIFY0(dsl_dataset_hold(dp, ddha->ddha_name, FTAG, &ds)); + dsl_destroy_head_sync_impl(ds, tx); + dsl_dataset_rele(ds, FTAG); +} + +static void +dsl_destroy_head_begin_sync(void *arg, dmu_tx_t *tx) +{ + dsl_destroy_head_arg_t *ddha = arg; + dsl_pool_t *dp = dmu_tx_pool(tx); + dsl_dataset_t *ds; + + VERIFY0(dsl_dataset_hold(dp, ddha->ddha_name, FTAG, &ds)); + + /* Mark it as inconsistent on-disk, in case we crash */ + dmu_buf_will_dirty(ds->ds_dbuf, tx); + ds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT; + + spa_history_log_internal_ds(ds, "destroy begin", tx, ""); + dsl_dataset_rele(ds, FTAG); +} + +int +dsl_destroy_head(const char *name) +{ + dsl_destroy_head_arg_t ddha; + int error; + spa_t *spa; + boolean_t isenabled; + +#ifdef _KERNEL + zfs_destroy_unmount_origin(name); +#endif + + error = spa_open(name, &spa, FTAG); + if (error != 0) + return (error); + isenabled = spa_feature_is_enabled(spa, + &spa_feature_table[SPA_FEATURE_ASYNC_DESTROY]); + spa_close(spa, FTAG); + + ddha.ddha_name = name; + + if (!isenabled) { + objset_t *os; + + error = dsl_sync_task(name, dsl_destroy_head_check, + dsl_destroy_head_begin_sync, &ddha, 0); + if (error != 0) + return (error); + + /* + * Head deletion is processed in one txg on old pools; + * remove the objects from open context so that the txg sync + * is not too long. + */ + error = dmu_objset_own(name, DMU_OST_ANY, B_FALSE, FTAG, &os); + if (error == 0) { + uint64_t obj; + uint64_t prev_snap_txg = + dmu_objset_ds(os)->ds_phys->ds_prev_snap_txg; + for (obj = 0; error == 0; + error = dmu_object_next(os, &obj, FALSE, + prev_snap_txg)) + (void) dmu_free_object(os, obj); + /* sync out all frees */ + txg_wait_synced(dmu_objset_pool(os), 0); + dmu_objset_disown(os, FTAG); + } + } + + return (dsl_sync_task(name, dsl_destroy_head_check, + dsl_destroy_head_sync, &ddha, 0)); +} + +/* + * Note, this function is used as the callback for dmu_objset_find(). We + * always return 0 so that we will continue to find and process + * inconsistent datasets, even if we encounter an error trying to + * process one of them. + */ +/* ARGSUSED */ +int +dsl_destroy_inconsistent(const char *dsname, void *arg) +{ + objset_t *os; + + if (dmu_objset_hold(dsname, FTAG, &os) == 0) { + boolean_t inconsistent = DS_IS_INCONSISTENT(dmu_objset_ds(os)); + dmu_objset_rele(os, FTAG); + if (inconsistent) + (void) dsl_destroy_head(dsname); + } + return (0); +} + + +#if defined(_KERNEL) && defined(HAVE_SPL) +EXPORT_SYMBOL(dsl_destroy_head); +EXPORT_SYMBOL(dsl_destroy_head_sync_impl); +EXPORT_SYMBOL(dsl_dataset_user_hold_check_one); +EXPORT_SYMBOL(dsl_destroy_snapshot_sync_impl); +EXPORT_SYMBOL(dsl_destroy_inconsistent); +EXPORT_SYMBOL(dsl_dataset_user_release_tmp); +EXPORT_SYMBOL(dsl_destroy_head_check_impl); +#endif |