/* * 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, 2017 by Delphix. All rights reserved. * Copyright (c) 2013 Steven Hartland. All rights reserved. * Copyright (c) 2013 by Joyent, Inc. All rights reserved. * Copyright (c) 2016 Actifio, Inc. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include int dsl_destroy_snapshot_check_impl(dsl_dataset_t *ds, boolean_t defer) { if (!ds->ds_is_snapshot) return (SET_ERROR(EINVAL)); if (dsl_dataset_long_held(ds)) return (SET_ERROR(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 (SET_ERROR(ENOTSUP)); return (0); } /* * If this snapshot has an elevated user reference count, * we can't destroy it yet. */ if (ds->ds_userrefs > 0) return (SET_ERROR(EBUSY)); /* * Can't delete a branch point. */ if (dsl_dataset_phys(ds)->ds_num_children > 1) return (SET_ERROR(EEXIST)); return (0); } int dsl_destroy_snapshot_check(void *arg, dmu_tx_t *tx) { dsl_destroy_snapshot_arg_t *ddsa = arg; const char *dsname = ddsa->ddsa_name; boolean_t defer = ddsa->ddsa_defer; dsl_pool_t *dp = dmu_tx_pool(tx); int error = 0; dsl_dataset_t *ds; error = dsl_dataset_hold(dp, dsname, FTAG, &ds); /* * If the snapshot does not exist, silently ignore it, and * dsl_destroy_snapshot_sync() will be a no-op * (it's "already destroyed"). */ if (error == ENOENT) return (0); if (error == 0) { error = dsl_destroy_snapshot_check_impl(ds, defer); dsl_dataset_rele(ds, FTAG); } return (error); } 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; ASSERT(!BP_IS_HOLE(bp)); if (bp->blk_birth <= dsl_dataset_phys(poa->ds)->ds_prev_snap_txg) { dsl_deadlist_insert(&poa->ds->ds_deadlist, bp, tx); if (poa->ds_prev && !poa->after_branch_point && bp->blk_birth > dsl_dataset_phys(poa->ds_prev)->ds_prev_snap_txg) { dsl_dataset_phys(poa->ds_prev)->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, ==, dsl_dataset_phys(ds)->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 = dsl_dataset_phys(ds)->ds_deadlist_obj; dsl_dataset_phys(ds)->ds_deadlist_obj = dsl_dataset_phys(ds_next)->ds_deadlist_obj; dsl_dataset_phys(ds_next)->ds_deadlist_obj = deadlist_obj; dsl_deadlist_open(&ds->ds_deadlist, mos, dsl_dataset_phys(ds)->ds_deadlist_obj); dsl_deadlist_open(&ds_next->ds_deadlist, mos, dsl_dataset_phys(ds_next)->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 (dsl_dir_phys(ds->ds_dir)->dd_clones == 0) return; zc = kmem_alloc(sizeof (zap_cursor_t), KM_SLEEP); za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP); for (zap_cursor_init(zc, mos, dsl_dir_phys(ds->ds_dir)->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); if (dsl_dataset_remap_deadlist_exists(clone)) { dsl_deadlist_remove_key( &clone->ds_remap_deadlist, mintxg, tx); } dsl_dataset_remove_clones_key(clone, mintxg, tx); } dsl_dataset_rele(clone, FTAG); } zap_cursor_fini(zc); kmem_free(za, sizeof (zap_attribute_t)); kmem_free(zc, sizeof (zap_cursor_t)); } static void dsl_destroy_snapshot_handle_remaps(dsl_dataset_t *ds, dsl_dataset_t *ds_next, dmu_tx_t *tx) { dsl_pool_t *dp = ds->ds_dir->dd_pool; /* Move blocks to be obsoleted to pool's obsolete list. */ if (dsl_dataset_remap_deadlist_exists(ds_next)) { if (!bpobj_is_open(&dp->dp_obsolete_bpobj)) dsl_pool_create_obsolete_bpobj(dp, tx); dsl_deadlist_move_bpobj(&ds_next->ds_remap_deadlist, &dp->dp_obsolete_bpobj, dsl_dataset_phys(ds)->ds_prev_snap_txg, tx); } /* Merge our deadlist into next's and free it. */ if (dsl_dataset_remap_deadlist_exists(ds)) { uint64_t remap_deadlist_object = dsl_dataset_get_remap_deadlist_object(ds); ASSERT(remap_deadlist_object != 0); mutex_enter(&ds_next->ds_remap_deadlist_lock); if (!dsl_dataset_remap_deadlist_exists(ds_next)) dsl_dataset_create_remap_deadlist(ds_next, tx); mutex_exit(&ds_next->ds_remap_deadlist_lock); dsl_deadlist_merge(&ds_next->ds_remap_deadlist, remap_deadlist_object, tx); dsl_dataset_destroy_remap_deadlist(ds, tx); } } void dsl_destroy_snapshot_sync_impl(dsl_dataset_t *ds, boolean_t defer, dmu_tx_t *tx) { 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; ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock)); rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); ASSERT3U(dsl_dataset_phys(ds)->ds_bp.blk_birth, <=, tx->tx_txg); rrw_exit(&ds->ds_bp_rwlock, FTAG); ASSERT(refcount_is_zero(&ds->ds_longholds)); if (defer && (ds->ds_userrefs > 0 || dsl_dataset_phys(ds)->ds_num_children > 1)) { ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS); dmu_buf_will_dirty(ds->ds_dbuf, tx); dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_DEFER_DESTROY; spa_history_log_internal_ds(ds, "defer_destroy", tx, ""); return; } ASSERT3U(dsl_dataset_phys(ds)->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; for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { if (ds->ds_feature_inuse[f]) { dsl_dataset_deactivate_feature(obj, f, tx); ds->ds_feature_inuse[f] = B_FALSE; } } if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { ASSERT3P(ds->ds_prev, ==, NULL); VERIFY0(dsl_dataset_hold_obj(dp, dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &ds_prev)); after_branch_point = (dsl_dataset_phys(ds_prev)->ds_next_snap_obj != obj); dmu_buf_will_dirty(ds_prev->ds_dbuf, tx); if (after_branch_point && dsl_dataset_phys(ds_prev)->ds_next_clones_obj != 0) { dsl_dataset_remove_from_next_clones(ds_prev, obj, tx); if (dsl_dataset_phys(ds)->ds_next_snap_obj != 0) { VERIFY0(zap_add_int(mos, dsl_dataset_phys(ds_prev)-> ds_next_clones_obj, dsl_dataset_phys(ds)->ds_next_snap_obj, tx)); } } if (!after_branch_point) { dsl_dataset_phys(ds_prev)->ds_next_snap_obj = dsl_dataset_phys(ds)->ds_next_snap_obj; } } dsl_dataset_t *ds_next; uint64_t old_unique; uint64_t used = 0, comp = 0, uncomp = 0; VERIFY0(dsl_dataset_hold_obj(dp, dsl_dataset_phys(ds)->ds_next_snap_obj, FTAG, &ds_next)); ASSERT3U(dsl_dataset_phys(ds_next)->ds_prev_snap_obj, ==, obj); old_unique = dsl_dataset_phys(ds_next)->ds_unique_bytes; dmu_buf_will_dirty(ds_next->ds_dbuf, tx); dsl_dataset_phys(ds_next)->ds_prev_snap_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj; dsl_dataset_phys(ds_next)->ds_prev_snap_txg = dsl_dataset_phys(ds)->ds_prev_snap_txg; ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, ==, ds_prev ? dsl_dataset_phys(ds_prev)->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, dsl_dataset_phys(ds_prev)->ds_prev_snap_txg, dsl_dataset_phys(ds)->ds_prev_snap_txg, &used, &comp, &uncomp); dsl_dataset_phys(ds_prev)->ds_unique_bytes += used; } /* Adjust snapused. */ dsl_deadlist_space_range(&ds_next->ds_deadlist, dsl_dataset_phys(ds)->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, dsl_dataset_phys(ds)->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, dsl_dataset_phys(ds)->ds_deadlist_obj, tx); } dsl_deadlist_close(&ds->ds_deadlist); dsl_deadlist_free(mos, dsl_dataset_phys(ds)->ds_deadlist_obj, tx); dmu_buf_will_dirty(ds->ds_dbuf, tx); dsl_dataset_phys(ds)->ds_deadlist_obj = 0; dsl_destroy_snapshot_handle_remaps(ds, ds_next, tx); /* Collapse range in clone heads */ dsl_dataset_remove_clones_key(ds, dsl_dataset_phys(ds)->ds_creation_txg, tx); if (ds_next->ds_is_snapshot) { 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, dsl_dataset_phys(ds_next)->ds_next_snap_obj, FTAG, &ds_nextnext)); dsl_deadlist_space_range(&ds_nextnext->ds_deadlist, dsl_dataset_phys(ds)->ds_prev_snap_txg, dsl_dataset_phys(ds)->ds_creation_txg, &used, &comp, &uncomp); dsl_dataset_phys(ds_next)->ds_unique_bytes += used; dsl_dataset_rele(ds_nextnext, FTAG); ASSERT3P(ds_next->ds_prev, ==, NULL); /* Collapse range in this head. */ dsl_dataset_t *hds; VERIFY0(dsl_dataset_hold_obj(dp, dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj, FTAG, &hds)); dsl_deadlist_remove_key(&hds->ds_deadlist, dsl_dataset_phys(ds)->ds_creation_txg, tx); if (dsl_dataset_remap_deadlist_exists(hds)) { dsl_deadlist_remove_key(&hds->ds_remap_deadlist, dsl_dataset_phys(ds)->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, dsl_dataset_phys(ds)->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 = dsl_dataset_phys(ds_next)->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 */ dsl_dataset_t *ds_head; ASSERT(dsl_dataset_phys(ds)->ds_snapnames_zapobj == 0); VERIFY0(dsl_dataset_hold_obj(dp, dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj, FTAG, &ds_head)); VERIFY0(dsl_dataset_get_snapname(ds)); #ifdef ZFS_DEBUG { uint64_t val; int err; 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, B_TRUE)); 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 (dsl_dataset_phys(ds)->ds_next_clones_obj != 0) { ASSERTV(uint64_t count); ASSERT0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, &count) && count == 0); VERIFY0(dmu_object_free(mos, dsl_dataset_phys(ds)->ds_next_clones_obj, tx)); } if (dsl_dataset_phys(ds)->ds_props_obj != 0) VERIFY0(zap_destroy(mos, dsl_dataset_phys(ds)->ds_props_obj, tx)); if (dsl_dataset_phys(ds)->ds_userrefs_obj != 0) VERIFY0(zap_destroy(mos, dsl_dataset_phys(ds)->ds_userrefs_obj, tx)); dsl_dir_rele(ds->ds_dir, ds); ds->ds_dir = NULL; dmu_object_free_zapified(mos, obj, tx); } void dsl_destroy_snapshot_sync(void *arg, dmu_tx_t *tx) { dsl_destroy_snapshot_arg_t *ddsa = arg; const char *dsname = ddsa->ddsa_name; boolean_t defer = ddsa->ddsa_defer; dsl_pool_t *dp = dmu_tx_pool(tx); dsl_dataset_t *ds; int error = dsl_dataset_hold(dp, dsname, FTAG, &ds); if (error == ENOENT) return; ASSERT0(error); dsl_destroy_snapshot_sync_impl(ds, defer, tx); zvol_remove_minors(dp->dp_spa, dsname, B_TRUE); 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) { if (nvlist_next_nvpair(snaps, NULL) == NULL) return (0); /* * lzc_destroy_snaps() is documented to take an nvlist whose * values "don't matter". We need to convert that nvlist to * one that we know can be converted to LUA. We also don't * care about any duplicate entries because the nvlist will * be converted to a LUA table which should take care of this. */ nvlist_t *snaps_normalized; VERIFY0(nvlist_alloc(&snaps_normalized, 0, KM_SLEEP)); for (nvpair_t *pair = nvlist_next_nvpair(snaps, NULL); pair != NULL; pair = nvlist_next_nvpair(snaps, pair)) { fnvlist_add_boolean_value(snaps_normalized, nvpair_name(pair), B_TRUE); } nvlist_t *arg; VERIFY0(nvlist_alloc(&arg, 0, KM_SLEEP)); fnvlist_add_nvlist(arg, "snaps", snaps_normalized); fnvlist_free(snaps_normalized); fnvlist_add_boolean_value(arg, "defer", defer); nvlist_t *wrapper; VERIFY0(nvlist_alloc(&wrapper, 0, KM_SLEEP)); fnvlist_add_nvlist(wrapper, ZCP_ARG_ARGLIST, arg); fnvlist_free(arg); const char *program = "arg = ...\n" "snaps = arg['snaps']\n" "defer = arg['defer']\n" "errors = { }\n" "has_errors = false\n" "for snap, v in pairs(snaps) do\n" " errno = zfs.check.destroy{snap, defer=defer}\n" " zfs.debug('snap: ' .. snap .. ' errno: ' .. errno)\n" " if errno == ENOENT then\n" " snaps[snap] = nil\n" " elseif errno ~= 0 then\n" " errors[snap] = errno\n" " has_errors = true\n" " end\n" "end\n" "if has_errors then\n" " return errors\n" "end\n" "for snap, v in pairs(snaps) do\n" " errno = zfs.sync.destroy{snap, defer=defer}\n" " assert(errno == 0)\n" "end\n" "return { }\n"; nvlist_t *result = fnvlist_alloc(); int error = zcp_eval(nvpair_name(nvlist_next_nvpair(snaps, NULL)), program, B_TRUE, 0, zfs_lua_max_memlimit, nvlist_next_nvpair(wrapper, NULL), result); if (error != 0) { char *errorstr = NULL; (void) nvlist_lookup_string(result, ZCP_RET_ERROR, &errorstr); if (errorstr != NULL) { zfs_dbgmsg(errorstr); } return (error); } fnvlist_free(wrapper); /* * lzc_destroy_snaps() is documented to fill the errlist with * int32 values, so we need to covert the int64 values that are * returned from LUA. */ int rv = 0; nvlist_t *errlist_raw = fnvlist_lookup_nvlist(result, ZCP_RET_RETURN); for (nvpair_t *pair = nvlist_next_nvpair(errlist_raw, NULL); pair != NULL; pair = nvlist_next_nvpair(errlist_raw, pair)) { int32_t val = (int32_t)fnvpair_value_int64(pair); if (rv == 0) rv = val; fnvlist_add_int32(errlist, nvpair_name(pair), val); } fnvlist_free(result); return (rv); } int dsl_destroy_snapshot(const char *name, boolean_t defer) { int error; nvlist_t *nvl = fnvlist_alloc(); nvlist_t *errlist = fnvlist_alloc(); 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_phys_t *zb, const dnode_phys_t *dnp, void *arg) { struct killarg *ka = arg; dmu_tx_t *tx = ka->tx; if (bp == NULL || BP_IS_HOLE(bp) || BP_IS_EMBEDDED(bp)) 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, >, dsl_dataset_phys(ka->ds)->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, dsl_dataset_phys(ds)->ds_prev_snap_txg, TRAVERSE_POST | TRAVERSE_NO_DECRYPT, kill_blkptr, &ka)); ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) || dsl_dataset_phys(ds)->ds_unique_bytes == 0); } int dsl_destroy_head_check_impl(dsl_dataset_t *ds, int expected_holds) { int error; uint64_t count; objset_t *mos; ASSERT(!ds->ds_is_snapshot); if (ds->ds_is_snapshot) return (SET_ERROR(EINVAL)); if (refcount_count(&ds->ds_longholds) != expected_holds) return (SET_ERROR(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 && dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == ds->ds_object) return (SET_ERROR(EBUSY)); /* * Can't delete if there are children of this fs. */ error = zap_count(mos, dsl_dir_phys(ds->ds_dir)->dd_child_dir_zapobj, &count); if (error != 0) return (error); if (count != 0) return (SET_ERROR(EEXIST)); if (dsl_dir_is_clone(ds->ds_dir) && DS_IS_DEFER_DESTROY(ds->ds_prev) && dsl_dataset_phys(ds->ds_prev)->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 (SET_ERROR(EBUSY)); } return (0); } 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(dsl_dir_phys(dd)->dd_head_dataset_obj); /* * Decrement the filesystem count for all parent filesystems. * * When we receive an incremental stream into a filesystem that already * exists, a temporary clone is created. We never count this temporary * clone, whose name begins with a '%'. */ if (dd->dd_myname[0] != '%' && dd->dd_parent != NULL) dsl_fs_ss_count_adjust(dd->dd_parent, -1, DD_FIELD_FILESYSTEM_COUNT, tx); /* * 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(dsl_dir_phys(dd)->dd_used_bytes); ASSERT0(dsl_dir_phys(dd)->dd_reserved); for (t = 0; t < DD_USED_NUM; t++) ASSERT0(dsl_dir_phys(dd)->dd_used_breakdown[t]); if (dd->dd_crypto_obj != 0) { dsl_crypto_key_destroy_sync(dd->dd_crypto_obj, tx); (void) spa_keystore_unload_wkey_impl(dp->dp_spa, dd->dd_object); } VERIFY0(zap_destroy(mos, dsl_dir_phys(dd)->dd_child_dir_zapobj, tx)); VERIFY0(zap_destroy(mos, dsl_dir_phys(dd)->dd_props_zapobj, tx)); VERIFY0(dsl_deleg_destroy(mos, dsl_dir_phys(dd)->dd_deleg_zapobj, tx)); VERIFY0(zap_remove(mos, dsl_dir_phys(dd->dd_parent)->dd_child_dir_zapobj, dd->dd_myname, tx)); dsl_dir_rele(dd, FTAG); dmu_object_free_zapified(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; ASSERT3U(dsl_dataset_phys(ds)->ds_num_children, <=, 1); ASSERT(ds->ds_prev == NULL || dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj != ds->ds_object); rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); ASSERT3U(dsl_dataset_phys(ds)->ds_bp.blk_birth, <=, tx->tx_txg); rrw_exit(&ds->ds_bp_rwlock, FTAG); 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) && dsl_dataset_phys(ds->ds_prev)->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); } obj = ds->ds_object; for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { if (ds->ds_feature_inuse[f]) { dsl_dataset_deactivate_feature(obj, f, tx); ds->ds_feature_inuse[f] = B_FALSE; } } dsl_scan_ds_destroyed(ds, tx); if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { /* This is a clone */ ASSERT(ds->ds_prev != NULL); ASSERT3U(dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj, !=, obj); ASSERT0(dsl_dataset_phys(ds)->ds_next_snap_obj); dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx); if (dsl_dataset_phys(ds->ds_prev)->ds_next_clones_obj != 0) { dsl_dataset_remove_from_next_clones(ds->ds_prev, obj, tx); } ASSERT3U(dsl_dataset_phys(ds->ds_prev)->ds_num_children, >, 1); dsl_dataset_phys(ds->ds_prev)->ds_num_children--; } /* * Destroy the deadlist. Unless it's a clone, the * deadlist should be empty since the dataset has no snapshots. * (If it's a clone, it's safe to ignore the deadlist contents * since they are still referenced by the origin snapshot.) */ dsl_deadlist_close(&ds->ds_deadlist); dsl_deadlist_free(mos, dsl_dataset_phys(ds)->ds_deadlist_obj, tx); dmu_buf_will_dirty(ds->ds_dbuf, tx); dsl_dataset_phys(ds)->ds_deadlist_obj = 0; if (dsl_dataset_remap_deadlist_exists(ds)) dsl_dataset_destroy_remap_deadlist(ds, tx); objset_t *os; VERIFY0(dmu_objset_from_ds(ds, &os)); if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_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, SPA_FEATURE_ASYNC_DESTROY)) { dsl_scan_t *scn = dp->dp_scan; spa_feature_incr(dp->dp_spa, SPA_FEATURE_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)); ASSERT(!scn->scn_async_destroying); scn->scn_async_destroying = B_TRUE; } used = dsl_dir_phys(ds->ds_dir)->dd_used_bytes; comp = dsl_dir_phys(ds->ds_dir)->dd_compressed_bytes; uncomp = dsl_dir_phys(ds->ds_dir)->dd_uncompressed_bytes; ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) || dsl_dataset_phys(ds)->ds_unique_bytes == used); rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); bptree_add(mos, dp->dp_bptree_obj, &dsl_dataset_phys(ds)->ds_bp, dsl_dataset_phys(ds)->ds_prev_snap_txg, used, comp, uncomp, tx); rrw_exit(&ds->ds_bp_rwlock, FTAG); 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, dsl_dir_phys(ds->ds_prev->ds_dir)->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); dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj = 0; ddobj = ds->ds_dir->dd_object; ASSERT(dsl_dataset_phys(ds)->ds_snapnames_zapobj != 0); VERIFY0(zap_destroy(mos, dsl_dataset_phys(ds)->ds_snapnames_zapobj, tx)); if (ds->ds_bookmarks != 0) { VERIFY0(zap_destroy(mos, ds->ds_bookmarks, tx)); spa_feature_decr(dp->dp_spa, SPA_FEATURE_BOOKMARKS, tx); } spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx); ASSERT0(dsl_dataset_phys(ds)->ds_next_clones_obj); ASSERT0(dsl_dataset_phys(ds)->ds_props_obj); ASSERT0(dsl_dataset_phys(ds)->ds_userrefs_obj); dsl_dir_rele(ds->ds_dir, ds); ds->ds_dir = NULL; dmu_object_free_zapified(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); } } 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); zvol_remove_minors(dp->dp_spa, ddha->ddha_name, B_TRUE); 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); dsl_dataset_phys(ds)->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_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, ZFS_SPACE_CHECK_DESTROY); 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, B_FALSE, FTAG, &os); if (error == 0) { uint64_t prev_snap_txg = dsl_dataset_phys(dmu_objset_ds(os))-> ds_prev_snap_txg; for (uint64_t obj = 0; error == 0; error = dmu_object_next(os, &obj, FALSE, prev_snap_txg)) (void) dmu_free_long_object(os, obj); /* sync out all frees */ txg_wait_synced(dmu_objset_pool(os), 0); dmu_objset_disown(os, B_FALSE, FTAG); } } return (dsl_sync_task(name, dsl_destroy_head_check, dsl_destroy_head_sync, &ddha, 0, ZFS_SPACE_CHECK_DESTROY)); } /* * 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 need_destroy = DS_IS_INCONSISTENT(dmu_objset_ds(os)); /* * If the dataset is inconsistent because a resumable receive * has failed, then do not destroy it. */ if (dsl_dataset_has_resume_receive_state(dmu_objset_ds(os))) need_destroy = B_FALSE; dmu_objset_rele(os, FTAG); if (need_destroy) (void) dsl_destroy_head(dsname); } return (0); } #if defined(_KERNEL) 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