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; } }
void dsl_destroy_snapshot_sync_impl(dsl_dataset_t *ds, boolean_t defer, dmu_tx_t *tx) { int err; 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; boolean_t book_exists = dsl_bookmark_ds_destroyed(ds, tx); for (spa_feature_t f = 0; f < SPA_FEATURES; f++) { if (dsl_dataset_feature_is_active(ds, f)) dsl_dataset_deactivate_feature(ds, f, tx); } 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; } }