dsl_destroy.c revision a2cdcdd260232b58202b11a9bfc0103c9449ed52
13b2aab1Matthew Ahrens/*
23b2aab1Matthew Ahrens * CDDL HEADER START
33b2aab1Matthew Ahrens *
43b2aab1Matthew Ahrens * The contents of this file are subject to the terms of the
53b2aab1Matthew Ahrens * Common Development and Distribution License (the "License").
63b2aab1Matthew Ahrens * You may not use this file except in compliance with the License.
73b2aab1Matthew Ahrens *
83b2aab1Matthew Ahrens * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
93b2aab1Matthew Ahrens * or http://www.opensolaris.org/os/licensing.
103b2aab1Matthew Ahrens * See the License for the specific language governing permissions
113b2aab1Matthew Ahrens * and limitations under the License.
123b2aab1Matthew Ahrens *
133b2aab1Matthew Ahrens * When distributing Covered Code, include this CDDL HEADER in each
143b2aab1Matthew Ahrens * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
153b2aab1Matthew Ahrens * If applicable, add the following below this CDDL HEADER, with the
163b2aab1Matthew Ahrens * fields enclosed by brackets "[]" replaced with your own identifying
173b2aab1Matthew Ahrens * information: Portions Copyright [yyyy] [name of copyright owner]
183b2aab1Matthew Ahrens *
193b2aab1Matthew Ahrens * CDDL HEADER END
203b2aab1Matthew Ahrens */
213b2aab1Matthew Ahrens/*
223b2aab1Matthew Ahrens * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
237802d7bMatthew Ahrens * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
24a7a845eSteven Hartland * Copyright (c) 2013 Steven Hartland. All rights reserved.
25a2afb61Jerry Jelinek * Copyright (c) 2013 by Joyent, Inc. All rights reserved.
263b2aab1Matthew Ahrens */
273b2aab1Matthew Ahrens
283b2aab1Matthew Ahrens#include <sys/zfs_context.h>
293b2aab1Matthew Ahrens#include <sys/dsl_userhold.h>
303b2aab1Matthew Ahrens#include <sys/dsl_dataset.h>
313b2aab1Matthew Ahrens#include <sys/dsl_synctask.h>
323b2aab1Matthew Ahrens#include <sys/dmu_tx.h>
333b2aab1Matthew Ahrens#include <sys/dsl_pool.h>
343b2aab1Matthew Ahrens#include <sys/dsl_dir.h>
353b2aab1Matthew Ahrens#include <sys/dmu_traverse.h>
363b2aab1Matthew Ahrens#include <sys/dsl_scan.h>
373b2aab1Matthew Ahrens#include <sys/dmu_objset.h>
383b2aab1Matthew Ahrens#include <sys/zap.h>
393b2aab1Matthew Ahrens#include <sys/zfeature.h>
403b2aab1Matthew Ahrens#include <sys/zfs_ioctl.h>
413b2aab1Matthew Ahrens#include <sys/dsl_deleg.h>
422acef22Matthew Ahrens#include <sys/dmu_impl.h>
433b2aab1Matthew Ahrens
443b2aab1Matthew Ahrenstypedef struct dmu_snapshots_destroy_arg {
453b2aab1Matthew Ahrens	nvlist_t *dsda_snaps;
463b2aab1Matthew Ahrens	nvlist_t *dsda_successful_snaps;
473b2aab1Matthew Ahrens	boolean_t dsda_defer;
483b2aab1Matthew Ahrens	nvlist_t *dsda_errlist;
493b2aab1Matthew Ahrens} dmu_snapshots_destroy_arg_t;
503b2aab1Matthew Ahrens
5134f2f8cMatthew Ahrensint
523b2aab1Matthew Ahrensdsl_destroy_snapshot_check_impl(dsl_dataset_t *ds, boolean_t defer)
533b2aab1Matthew Ahrens{
54bc9014eJustin Gibbs	if (!ds->ds_is_snapshot)
55be6fd75Matthew Ahrens		return (SET_ERROR(EINVAL));
563b2aab1Matthew Ahrens
573b2aab1Matthew Ahrens	if (dsl_dataset_long_held(ds))
58be6fd75Matthew Ahrens		return (SET_ERROR(EBUSY));
593b2aab1Matthew Ahrens
603b2aab1Matthew Ahrens	/*
613b2aab1Matthew Ahrens	 * Only allow deferred destroy on pools that support it.
623b2aab1Matthew Ahrens	 * NOTE: deferred destroy is only supported on snapshots.
633b2aab1Matthew Ahrens	 */
643b2aab1Matthew Ahrens	if (defer) {
653b2aab1Matthew Ahrens		if (spa_version(ds->ds_dir->dd_pool->dp_spa) <
663b2aab1Matthew Ahrens		    SPA_VERSION_USERREFS)
67be6fd75Matthew Ahrens			return (SET_ERROR(ENOTSUP));
683b2aab1Matthew Ahrens		return (0);
693b2aab1Matthew Ahrens	}
703b2aab1Matthew Ahrens
713b2aab1Matthew Ahrens	/*
723b2aab1Matthew Ahrens	 * If this snapshot has an elevated user reference count,
733b2aab1Matthew Ahrens	 * we can't destroy it yet.
743b2aab1Matthew Ahrens	 */
753b2aab1Matthew Ahrens	if (ds->ds_userrefs > 0)
76be6fd75Matthew Ahrens		return (SET_ERROR(EBUSY));
773b2aab1Matthew Ahrens
783b2aab1Matthew Ahrens	/*
793b2aab1Matthew Ahrens	 * Can't delete a branch point.
803b2aab1Matthew Ahrens	 */
81c137962Justin T. Gibbs	if (dsl_dataset_phys(ds)->ds_num_children > 1)
82be6fd75Matthew Ahrens		return (SET_ERROR(EEXIST));
833b2aab1Matthew Ahrens
843b2aab1Matthew Ahrens	return (0);
853b2aab1Matthew Ahrens}
863b2aab1Matthew Ahrens
873b2aab1Matthew Ahrensstatic int
883b2aab1Matthew Ahrensdsl_destroy_snapshot_check(void *arg, dmu_tx_t *tx)
893b2aab1Matthew Ahrens{
903b2aab1Matthew Ahrens	dmu_snapshots_destroy_arg_t *dsda = arg;
913b2aab1Matthew Ahrens	dsl_pool_t *dp = dmu_tx_pool(tx);
923b2aab1Matthew Ahrens	nvpair_t *pair;
933b2aab1Matthew Ahrens	int error = 0;
943b2aab1Matthew Ahrens
953b2aab1Matthew Ahrens	if (!dmu_tx_is_syncing(tx))
963b2aab1Matthew Ahrens		return (0);
973b2aab1Matthew Ahrens
983b2aab1Matthew Ahrens	for (pair = nvlist_next_nvpair(dsda->dsda_snaps, NULL);
993b2aab1Matthew Ahrens	    pair != NULL; pair = nvlist_next_nvpair(dsda->dsda_snaps, pair)) {
1003b2aab1Matthew Ahrens		dsl_dataset_t *ds;
1013b2aab1Matthew Ahrens
1023b2aab1Matthew Ahrens		error = dsl_dataset_hold(dp, nvpair_name(pair),
1033b2aab1Matthew Ahrens		    FTAG, &ds);
1043b2aab1Matthew Ahrens
1053b2aab1Matthew Ahrens		/*
1063b2aab1Matthew Ahrens		 * If the snapshot does not exist, silently ignore it
1073b2aab1Matthew Ahrens		 * (it's "already destroyed").
1083b2aab1Matthew Ahrens		 */
1093b2aab1Matthew Ahrens		if (error == ENOENT)
1103b2aab1Matthew Ahrens			continue;
1113b2aab1Matthew Ahrens
1123b2aab1Matthew Ahrens		if (error == 0) {
1133b2aab1Matthew Ahrens			error = dsl_destroy_snapshot_check_impl(ds,
1143b2aab1Matthew Ahrens			    dsda->dsda_defer);
1153b2aab1Matthew Ahrens			dsl_dataset_rele(ds, FTAG);
1163b2aab1Matthew Ahrens		}
1173b2aab1Matthew Ahrens
1183b2aab1Matthew Ahrens		if (error == 0) {
1193b2aab1Matthew Ahrens			fnvlist_add_boolean(dsda->dsda_successful_snaps,
1203b2aab1Matthew Ahrens			    nvpair_name(pair));
1213b2aab1Matthew Ahrens		} else {
1223b2aab1Matthew Ahrens			fnvlist_add_int32(dsda->dsda_errlist,
1233b2aab1Matthew Ahrens			    nvpair_name(pair), error);
1243b2aab1Matthew Ahrens		}
1253b2aab1Matthew Ahrens	}
1263b2aab1Matthew Ahrens
1273b2aab1Matthew Ahrens	pair = nvlist_next_nvpair(dsda->dsda_errlist, NULL);
1283b2aab1Matthew Ahrens	if (pair != NULL)
1293b2aab1Matthew Ahrens		return (fnvpair_value_int32(pair));
130a7a845eSteven Hartland
1313b2aab1Matthew Ahrens	return (0);
1323b2aab1Matthew Ahrens}
1333b2aab1Matthew Ahrens
1343b2aab1Matthew Ahrensstruct process_old_arg {
1353b2aab1Matthew Ahrens	dsl_dataset_t *ds;
1363b2aab1Matthew Ahrens	dsl_dataset_t *ds_prev;
1373b2aab1Matthew Ahrens	boolean_t after_branch_point;
1383b2aab1Matthew Ahrens	zio_t *pio;
1393b2aab1Matthew Ahrens	uint64_t used, comp, uncomp;
1403b2aab1Matthew Ahrens};
1413b2aab1Matthew Ahrens
1423b2aab1Matthew Ahrensstatic int
1433b2aab1Matthew Ahrensprocess_old_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
1443b2aab1Matthew Ahrens{
1453b2aab1Matthew Ahrens	struct process_old_arg *poa = arg;
1463b2aab1Matthew Ahrens	dsl_pool_t *dp = poa->ds->ds_dir->dd_pool;
1473b2aab1Matthew Ahrens
14843466aaMax Grossman	ASSERT(!BP_IS_HOLE(bp));
14943466aaMax Grossman
150c137962Justin T. Gibbs	if (bp->blk_birth <= dsl_dataset_phys(poa->ds)->ds_prev_snap_txg) {
1513b2aab1Matthew Ahrens		dsl_deadlist_insert(&poa->ds->ds_deadlist, bp, tx);
1523b2aab1Matthew Ahrens		if (poa->ds_prev && !poa->after_branch_point &&
1533b2aab1Matthew Ahrens		    bp->blk_birth >
154c137962Justin T. Gibbs		    dsl_dataset_phys(poa->ds_prev)->ds_prev_snap_txg) {
155c137962Justin T. Gibbs			dsl_dataset_phys(poa->ds_prev)->ds_unique_bytes +=
1563b2aab1Matthew Ahrens			    bp_get_dsize_sync(dp->dp_spa, bp);
1573b2aab1Matthew Ahrens		}
1583b2aab1Matthew Ahrens	} else {
1593b2aab1Matthew Ahrens		poa->used += bp_get_dsize_sync(dp->dp_spa, bp);
1603b2aab1Matthew Ahrens		poa->comp += BP_GET_PSIZE(bp);
1613b2aab1Matthew Ahrens		poa->uncomp += BP_GET_UCSIZE(bp);
1623b2aab1Matthew Ahrens		dsl_free_sync(poa->pio, dp, tx->tx_txg, bp);
1633b2aab1Matthew Ahrens	}
1643b2aab1Matthew Ahrens	return (0);
1653b2aab1Matthew Ahrens}
1663b2aab1Matthew Ahrens
1673b2aab1Matthew Ahrensstatic void
1683b2aab1Matthew Ahrensprocess_old_deadlist(dsl_dataset_t *ds, dsl_dataset_t *ds_prev,
1693b2aab1Matthew Ahrens    dsl_dataset_t *ds_next, boolean_t after_branch_point, dmu_tx_t *tx)
1703b2aab1Matthew Ahrens{
1713b2aab1Matthew Ahrens	struct process_old_arg poa = { 0 };
1723b2aab1Matthew Ahrens	dsl_pool_t *dp = ds->ds_dir->dd_pool;
1733b2aab1Matthew Ahrens	objset_t *mos = dp->dp_meta_objset;
1743b2aab1Matthew Ahrens	uint64_t deadlist_obj;
1753b2aab1Matthew Ahrens
1763b2aab1Matthew Ahrens	ASSERT(ds->ds_deadlist.dl_oldfmt);
1773b2aab1Matthew Ahrens	ASSERT(ds_next->ds_deadlist.dl_oldfmt);
1783b2aab1Matthew Ahrens
1793b2aab1Matthew Ahrens	poa.ds = ds;
1803b2aab1Matthew Ahrens	poa.ds_prev = ds_prev;
1813b2aab1Matthew Ahrens	poa.after_branch_point = after_branch_point;
1823b2aab1Matthew Ahrens	poa.pio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
1833b2aab1Matthew Ahrens	VERIFY0(bpobj_iterate(&ds_next->ds_deadlist.dl_bpobj,
1843b2aab1Matthew Ahrens	    process_old_cb, &poa, tx));
1853b2aab1Matthew Ahrens	VERIFY0(zio_wait(poa.pio));
186c137962Justin T. Gibbs	ASSERT3U(poa.used, ==, dsl_dataset_phys(ds)->ds_unique_bytes);
1873b2aab1Matthew Ahrens
1883b2aab1Matthew Ahrens	/* change snapused */
1893b2aab1Matthew Ahrens	dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP,
1903b2aab1Matthew Ahrens	    -poa.used, -poa.comp, -poa.uncomp, tx);
1913b2aab1Matthew Ahrens
1923b2aab1Matthew Ahrens	/* swap next's deadlist to our deadlist */
1933b2aab1Matthew Ahrens	dsl_deadlist_close(&ds->ds_deadlist);
1943b2aab1Matthew Ahrens	dsl_deadlist_close(&ds_next->ds_deadlist);
195c137962Justin T. Gibbs	deadlist_obj = dsl_dataset_phys(ds)->ds_deadlist_obj;
196c137962Justin T. Gibbs	dsl_dataset_phys(ds)->ds_deadlist_obj =
197c137962Justin T. Gibbs	    dsl_dataset_phys(ds_next)->ds_deadlist_obj;
198c137962Justin T. Gibbs	dsl_dataset_phys(ds_next)->ds_deadlist_obj = deadlist_obj;
199c137962Justin T. Gibbs	dsl_deadlist_open(&ds->ds_deadlist, mos,
200c137962Justin T. Gibbs	    dsl_dataset_phys(ds)->ds_deadlist_obj);
2013b2aab1Matthew Ahrens	dsl_deadlist_open(&ds_next->ds_deadlist, mos,
202c137962Justin T. Gibbs	    dsl_dataset_phys(ds_next)->ds_deadlist_obj);
2033b2aab1Matthew Ahrens}
2043b2aab1Matthew Ahrens
2053b2aab1Matthew Ahrensstatic void
2063b2aab1Matthew Ahrensdsl_dataset_remove_clones_key(dsl_dataset_t *ds, uint64_t mintxg, dmu_tx_t *tx)
2073b2aab1Matthew Ahrens{
2083b2aab1Matthew Ahrens	objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
2093b2aab1Matthew Ahrens	zap_cursor_t zc;
2103b2aab1Matthew Ahrens	zap_attribute_t za;
2113b2aab1Matthew Ahrens
2123b2aab1Matthew Ahrens	/*
2133b2aab1Matthew Ahrens	 * If it is the old version, dd_clones doesn't exist so we can't
2143b2aab1Matthew Ahrens	 * find the clones, but dsl_deadlist_remove_key() is a no-op so it
2153b2aab1Matthew Ahrens	 * doesn't matter.
2163b2aab1Matthew Ahrens	 */
217c137962Justin T. Gibbs	if (dsl_dir_phys(ds->ds_dir)->dd_clones == 0)
2183b2aab1Matthew Ahrens		return;
2193b2aab1Matthew Ahrens
220c137962Justin T. Gibbs	for (zap_cursor_init(&zc, mos, dsl_dir_phys(ds->ds_dir)->dd_clones);
2213b2aab1Matthew Ahrens	    zap_cursor_retrieve(&zc, &za) == 0;
2223b2aab1Matthew Ahrens	    zap_cursor_advance(&zc)) {
2233b2aab1Matthew Ahrens		dsl_dataset_t *clone;
2243b2aab1Matthew Ahrens
2253b2aab1Matthew Ahrens		VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool,
2263b2aab1Matthew Ahrens		    za.za_first_integer, FTAG, &clone));
2273b2aab1Matthew Ahrens		if (clone->ds_dir->dd_origin_txg > mintxg) {
2283b2aab1Matthew Ahrens			dsl_deadlist_remove_key(&clone->ds_deadlist,
2293b2aab1Matthew Ahrens			    mintxg, tx);
2303b2aab1Matthew Ahrens			dsl_dataset_remove_clones_key(clone, mintxg, tx);
2313b2aab1Matthew Ahrens		}
2323b2aab1Matthew Ahrens		dsl_dataset_rele(clone, FTAG);
2333b2aab1Matthew Ahrens	}
2343b2aab1Matthew Ahrens	zap_cursor_fini(&zc);
2353b2aab1Matthew Ahrens}
2363b2aab1Matthew Ahrens
2373b2aab1Matthew Ahrensvoid
2383b2aab1Matthew Ahrensdsl_destroy_snapshot_sync_impl(dsl_dataset_t *ds, boolean_t defer, dmu_tx_t *tx)
2393b2aab1Matthew Ahrens{
2403b2aab1Matthew Ahrens	int err;
2413b2aab1Matthew Ahrens	int after_branch_point = FALSE;
2423b2aab1Matthew Ahrens	dsl_pool_t *dp = ds->ds_dir->dd_pool;
2433b2aab1Matthew Ahrens	objset_t *mos = dp->dp_meta_objset;
2443b2aab1Matthew Ahrens	dsl_dataset_t *ds_prev = NULL;
2453b2aab1Matthew Ahrens	uint64_t obj;
2463b2aab1Matthew Ahrens
2473b2aab1Matthew Ahrens	ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
248c137962Justin T. Gibbs	ASSERT3U(dsl_dataset_phys(ds)->ds_bp.blk_birth, <=, tx->tx_txg);
2493b2aab1Matthew Ahrens	ASSERT(refcount_is_zero(&ds->ds_longholds));
2503b2aab1Matthew Ahrens
2513b2aab1Matthew Ahrens	if (defer &&
252c137962Justin T. Gibbs	    (ds->ds_userrefs > 0 ||
253c137962Justin T. Gibbs	    dsl_dataset_phys(ds)->ds_num_children > 1)) {
2543b2aab1Matthew Ahrens		ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS);
2553b2aab1Matthew Ahrens		dmu_buf_will_dirty(ds->ds_dbuf, tx);
256c137962Justin T. Gibbs		dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_DEFER_DESTROY;
2573b2aab1Matthew Ahrens		spa_history_log_internal_ds(ds, "defer_destroy", tx, "");
2583b2aab1Matthew Ahrens		return;
2593b2aab1Matthew Ahrens	}
2603b2aab1Matthew Ahrens
261c137962Justin T. Gibbs	ASSERT3U(dsl_dataset_phys(ds)->ds_num_children, <=, 1);
2623b2aab1Matthew Ahrens
2633b2aab1Matthew Ahrens	/* We need to log before removing it from the namespace. */
2643b2aab1Matthew Ahrens	spa_history_log_internal_ds(ds, "destroy", tx, "");
2653b2aab1Matthew Ahrens
2663b2aab1Matthew Ahrens	dsl_scan_ds_destroyed(ds, tx);
2673b2aab1Matthew Ahrens
2683b2aab1Matthew Ahrens	obj = ds->ds_object;
2693b2aab1Matthew Ahrens
270b515258Matthew Ahrens	if (ds->ds_large_blocks) {
271b515258Matthew Ahrens		ASSERT0(zap_contains(mos, obj, DS_FIELD_LARGE_BLOCKS));
272b515258Matthew Ahrens		spa_feature_decr(dp->dp_spa, SPA_FEATURE_LARGE_BLOCKS, tx);
273b515258Matthew Ahrens	}
274c137962Justin T. Gibbs	if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) {
2753b2aab1Matthew Ahrens		ASSERT3P(ds->ds_prev, ==, NULL);
2763b2aab1Matthew Ahrens		VERIFY0(dsl_dataset_hold_obj(dp,
277c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &ds_prev));
2783b2aab1Matthew Ahrens		after_branch_point =
279c137962Justin T. Gibbs		    (dsl_dataset_phys(ds_prev)->ds_next_snap_obj != obj);
2803b2aab1Matthew Ahrens
2813b2aab1Matthew Ahrens		dmu_buf_will_dirty(ds_prev->ds_dbuf, tx);
2823b2aab1Matthew Ahrens		if (after_branch_point &&
283c137962Justin T. Gibbs		    dsl_dataset_phys(ds_prev)->ds_next_clones_obj != 0) {
2843b2aab1Matthew Ahrens			dsl_dataset_remove_from_next_clones(ds_prev, obj, tx);
285c137962Justin T. Gibbs			if (dsl_dataset_phys(ds)->ds_next_snap_obj != 0) {
2863b2aab1Matthew Ahrens				VERIFY0(zap_add_int(mos,
287c137962Justin T. Gibbs				    dsl_dataset_phys(ds_prev)->
288c137962Justin T. Gibbs				    ds_next_clones_obj,
289c137962Justin T. Gibbs				    dsl_dataset_phys(ds)->ds_next_snap_obj,
290c137962Justin T. Gibbs				    tx));
2913b2aab1Matthew Ahrens			}
2923b2aab1Matthew Ahrens		}
2933b2aab1Matthew Ahrens		if (!after_branch_point) {
294c137962Justin T. Gibbs			dsl_dataset_phys(ds_prev)->ds_next_snap_obj =
295c137962Justin T. Gibbs			    dsl_dataset_phys(ds)->ds_next_snap_obj;
2963b2aab1Matthew Ahrens		}
2973b2aab1Matthew Ahrens	}
2983b2aab1Matthew Ahrens
2993b2aab1Matthew Ahrens	dsl_dataset_t *ds_next;
3003b2aab1Matthew Ahrens	uint64_t old_unique;
3013b2aab1Matthew Ahrens	uint64_t used = 0, comp = 0, uncomp = 0;
3023b2aab1Matthew Ahrens
3033b2aab1Matthew Ahrens	VERIFY0(dsl_dataset_hold_obj(dp,
304c137962Justin T. Gibbs	    dsl_dataset_phys(ds)->ds_next_snap_obj, FTAG, &ds_next));
305c137962Justin T. Gibbs	ASSERT3U(dsl_dataset_phys(ds_next)->ds_prev_snap_obj, ==, obj);
3063b2aab1Matthew Ahrens
307c137962Justin T. Gibbs	old_unique = dsl_dataset_phys(ds_next)->ds_unique_bytes;
3083b2aab1Matthew Ahrens
3093b2aab1Matthew Ahrens	dmu_buf_will_dirty(ds_next->ds_dbuf, tx);
310c137962Justin T. Gibbs	dsl_dataset_phys(ds_next)->ds_prev_snap_obj =
311c137962Justin T. Gibbs	    dsl_dataset_phys(ds)->ds_prev_snap_obj;
312c137962Justin T. Gibbs	dsl_dataset_phys(ds_next)->ds_prev_snap_txg =
313c137962Justin T. Gibbs	    dsl_dataset_phys(ds)->ds_prev_snap_txg;
314c137962Justin T. Gibbs	ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, ==,
315c137962Justin T. Gibbs	    ds_prev ? dsl_dataset_phys(ds_prev)->ds_creation_txg : 0);
3163b2aab1Matthew Ahrens
3173b2aab1Matthew Ahrens	if (ds_next->ds_deadlist.dl_oldfmt) {
3183b2aab1Matthew Ahrens		process_old_deadlist(ds, ds_prev, ds_next,
3193b2aab1Matthew Ahrens		    after_branch_point, tx);
3203b2aab1Matthew Ahrens	} else {
3213b2aab1Matthew Ahrens		/* Adjust prev's unique space. */
3223b2aab1Matthew Ahrens		if (ds_prev && !after_branch_point) {
3233b2aab1Matthew Ahrens			dsl_deadlist_space_range(&ds_next->ds_deadlist,
324c137962Justin T. Gibbs			    dsl_dataset_phys(ds_prev)->ds_prev_snap_txg,
325c137962Justin T. Gibbs			    dsl_dataset_phys(ds)->ds_prev_snap_txg,
3263b2aab1Matthew Ahrens			    &used, &comp, &uncomp);
327c137962Justin T. Gibbs			dsl_dataset_phys(ds_prev)->ds_unique_bytes += used;
3283b2aab1Matthew Ahrens		}
3293b2aab1Matthew Ahrens
3303b2aab1Matthew Ahrens		/* Adjust snapused. */
3313b2aab1Matthew Ahrens		dsl_deadlist_space_range(&ds_next->ds_deadlist,
332c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_prev_snap_txg, UINT64_MAX,
3333b2aab1Matthew Ahrens		    &used, &comp, &uncomp);
3343b2aab1Matthew Ahrens		dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP,
3353b2aab1Matthew Ahrens		    -used, -comp, -uncomp, tx);
3363b2aab1Matthew Ahrens
3373b2aab1Matthew Ahrens		/* Move blocks to be freed to pool's free list. */
3383b2aab1Matthew Ahrens		dsl_deadlist_move_bpobj(&ds_next->ds_deadlist,
339c137962Justin T. Gibbs		    &dp->dp_free_bpobj, dsl_dataset_phys(ds)->ds_prev_snap_txg,
3403b2aab1Matthew Ahrens		    tx);
3413b2aab1Matthew Ahrens		dsl_dir_diduse_space(tx->tx_pool->dp_free_dir,
3423b2aab1Matthew Ahrens		    DD_USED_HEAD, used, comp, uncomp, tx);
3433b2aab1Matthew Ahrens
3443b2aab1Matthew Ahrens		/* Merge our deadlist into next's and free it. */
3453b2aab1Matthew Ahrens		dsl_deadlist_merge(&ds_next->ds_deadlist,
346c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_deadlist_obj, tx);
3473b2aab1Matthew Ahrens	}
3483b2aab1Matthew Ahrens	dsl_deadlist_close(&ds->ds_deadlist);
349c137962Justin T. Gibbs	dsl_deadlist_free(mos, dsl_dataset_phys(ds)->ds_deadlist_obj, tx);
3503b2aab1Matthew Ahrens	dmu_buf_will_dirty(ds->ds_dbuf, tx);
351c137962Justin T. Gibbs	dsl_dataset_phys(ds)->ds_deadlist_obj = 0;
3523b2aab1Matthew Ahrens
3533b2aab1Matthew Ahrens	/* Collapse range in clone heads */
3543b2aab1Matthew Ahrens	dsl_dataset_remove_clones_key(ds,
355c137962Justin T. Gibbs	    dsl_dataset_phys(ds)->ds_creation_txg, tx);
3563b2aab1Matthew Ahrens
357bc9014eJustin Gibbs	if (ds_next->ds_is_snapshot) {
3583b2aab1Matthew Ahrens		dsl_dataset_t *ds_nextnext;
3593b2aab1Matthew Ahrens
3603b2aab1Matthew Ahrens		/*
3613b2aab1Matthew Ahrens		 * Update next's unique to include blocks which
3623b2aab1Matthew Ahrens		 * were previously shared by only this snapshot
3633b2aab1Matthew Ahrens		 * and it.  Those blocks will be born after the
3643b2aab1Matthew Ahrens		 * prev snap and before this snap, and will have
3653b2aab1Matthew Ahrens		 * died after the next snap and before the one
3663b2aab1Matthew Ahrens		 * after that (ie. be on the snap after next's
3673b2aab1Matthew Ahrens		 * deadlist).
3683b2aab1Matthew Ahrens		 */
3693b2aab1Matthew Ahrens		VERIFY0(dsl_dataset_hold_obj(dp,
370c137962Justin T. Gibbs		    dsl_dataset_phys(ds_next)->ds_next_snap_obj,
371c137962Justin T. Gibbs		    FTAG, &ds_nextnext));
3723b2aab1Matthew Ahrens		dsl_deadlist_space_range(&ds_nextnext->ds_deadlist,
373c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_prev_snap_txg,
374c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_creation_txg,
3753b2aab1Matthew Ahrens		    &used, &comp, &uncomp);
376c137962Justin T. Gibbs		dsl_dataset_phys(ds_next)->ds_unique_bytes += used;
3773b2aab1Matthew Ahrens		dsl_dataset_rele(ds_nextnext, FTAG);
3783b2aab1Matthew Ahrens		ASSERT3P(ds_next->ds_prev, ==, NULL);
3793b2aab1Matthew Ahrens
3803b2aab1Matthew Ahrens		/* Collapse range in this head. */
3813b2aab1Matthew Ahrens		dsl_dataset_t *hds;
3823b2aab1Matthew Ahrens		VERIFY0(dsl_dataset_hold_obj(dp,
383c137962Justin T. Gibbs		    dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj, FTAG, &hds));
3843b2aab1Matthew Ahrens		dsl_deadlist_remove_key(&hds->ds_deadlist,
385c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_creation_txg, tx);
3863b2aab1Matthew Ahrens		dsl_dataset_rele(hds, FTAG);
3873b2aab1Matthew Ahrens
3883b2aab1Matthew Ahrens	} else {
3893b2aab1Matthew Ahrens		ASSERT3P(ds_next->ds_prev, ==, ds);
3903b2aab1Matthew Ahrens		dsl_dataset_rele(ds_next->ds_prev, ds_next);
3913b2aab1Matthew Ahrens		ds_next->ds_prev = NULL;
3923b2aab1Matthew Ahrens		if (ds_prev) {
3933b2aab1Matthew Ahrens			VERIFY0(dsl_dataset_hold_obj(dp,
394c137962Justin T. Gibbs			    dsl_dataset_phys(ds)->ds_prev_snap_obj,
3953b2aab1Matthew Ahrens			    ds_next, &ds_next->ds_prev));
3963b2aab1Matthew Ahrens		}
3973b2aab1Matthew Ahrens
3983b2aab1Matthew Ahrens		dsl_dataset_recalc_head_uniq(ds_next);
3993b2aab1Matthew Ahrens
4003b2aab1Matthew Ahrens		/*
4013b2aab1Matthew Ahrens		 * Reduce the amount of our unconsumed refreservation
4023b2aab1Matthew Ahrens		 * being charged to our parent by the amount of
4033b2aab1Matthew Ahrens		 * new unique data we have gained.
4043b2aab1Matthew Ahrens		 */
4053b2aab1Matthew Ahrens		if (old_unique < ds_next->ds_reserved) {
4063b2aab1Matthew Ahrens			int64_t mrsdelta;
4073b2aab1Matthew Ahrens			uint64_t new_unique =
408c137962Justin T. Gibbs			    dsl_dataset_phys(ds_next)->ds_unique_bytes;
4093b2aab1Matthew Ahrens
4103b2aab1Matthew Ahrens			ASSERT(old_unique <= new_unique);
4113b2aab1Matthew Ahrens			mrsdelta = MIN(new_unique - old_unique,
4123b2aab1Matthew Ahrens			    ds_next->ds_reserved - old_unique);
4133b2aab1Matthew Ahrens			dsl_dir_diduse_space(ds->ds_dir,
4143b2aab1Matthew Ahrens			    DD_USED_REFRSRV, -mrsdelta, 0, 0, tx);
4153b2aab1Matthew Ahrens		}
4163b2aab1Matthew Ahrens	}
4173b2aab1Matthew Ahrens	dsl_dataset_rele(ds_next, FTAG);
4183b2aab1Matthew Ahrens
4193b2aab1Matthew Ahrens	/*
4203b2aab1Matthew Ahrens	 * This must be done after the dsl_traverse(), because it will
4213b2aab1Matthew Ahrens	 * re-open the objset.
4223b2aab1Matthew Ahrens	 */
4233b2aab1Matthew Ahrens	if (ds->ds_objset) {
4243b2aab1Matthew Ahrens		dmu_objset_evict(ds->ds_objset);
4253b2aab1Matthew Ahrens		ds->ds_objset = NULL;
4263b2aab1Matthew Ahrens	}
4273b2aab1Matthew Ahrens
4283b2aab1Matthew Ahrens	/* remove from snapshot namespace */
4293b2aab1Matthew Ahrens	dsl_dataset_t *ds_head;
430c137962Justin T. Gibbs	ASSERT(dsl_dataset_phys(ds)->ds_snapnames_zapobj == 0);
4313b2aab1Matthew Ahrens	VERIFY0(dsl_dataset_hold_obj(dp,
432c137962Justin T. Gibbs	    dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj, FTAG, &ds_head));
4333b2aab1Matthew Ahrens	VERIFY0(dsl_dataset_get_snapname(ds));
4343b2aab1Matthew Ahrens#ifdef ZFS_DEBUG
4353b2aab1Matthew Ahrens	{
4363b2aab1Matthew Ahrens		uint64_t val;
4373b2aab1Matthew Ahrens
4383b2aab1Matthew Ahrens		err = dsl_dataset_snap_lookup(ds_head,
4393b2aab1Matthew Ahrens		    ds->ds_snapname, &val);
4403b2aab1Matthew Ahrens		ASSERT0(err);
4413b2aab1Matthew Ahrens		ASSERT3U(val, ==, obj);
4423b2aab1Matthew Ahrens	}
4433b2aab1Matthew Ahrens#endif
444a2afb61Jerry Jelinek	VERIFY0(dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx, B_TRUE));
4453b2aab1Matthew Ahrens	dsl_dataset_rele(ds_head, FTAG);
4463b2aab1Matthew Ahrens
4473b2aab1Matthew Ahrens	if (ds_prev != NULL)
4483b2aab1Matthew Ahrens		dsl_dataset_rele(ds_prev, FTAG);
4493b2aab1Matthew Ahrens
4503b2aab1Matthew Ahrens	spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx);
4513b2aab1Matthew Ahrens
452c137962Justin T. Gibbs	if (dsl_dataset_phys(ds)->ds_next_clones_obj != 0) {
4533b2aab1Matthew Ahrens		uint64_t count;
4543b2aab1Matthew Ahrens		ASSERT0(zap_count(mos,
455c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_next_clones_obj, &count) &&
456c137962Justin T. Gibbs		    count == 0);
4573b2aab1Matthew Ahrens		VERIFY0(dmu_object_free(mos,
458c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_next_clones_obj, tx));
4593b2aab1Matthew Ahrens	}
460c137962Justin T. Gibbs	if (dsl_dataset_phys(ds)->ds_props_obj != 0)
461c137962Justin T. Gibbs		VERIFY0(zap_destroy(mos, dsl_dataset_phys(ds)->ds_props_obj,
462c137962Justin T. Gibbs		    tx));
463c137962Justin T. Gibbs	if (dsl_dataset_phys(ds)->ds_userrefs_obj != 0)
464c137962Justin T. Gibbs		VERIFY0(zap_destroy(mos, dsl_dataset_phys(ds)->ds_userrefs_obj,
465c137962Justin T. Gibbs		    tx));
4663b2aab1Matthew Ahrens	dsl_dir_rele(ds->ds_dir, ds);
4673b2aab1Matthew Ahrens	ds->ds_dir = NULL;
4682acef22Matthew Ahrens	dmu_object_free_zapified(mos, obj, tx);
4693b2aab1Matthew Ahrens}
4703b2aab1Matthew Ahrens
4713b2aab1Matthew Ahrensstatic void
4723b2aab1Matthew Ahrensdsl_destroy_snapshot_sync(void *arg, dmu_tx_t *tx)
4733b2aab1Matthew Ahrens{
4743b2aab1Matthew Ahrens	dmu_snapshots_destroy_arg_t *dsda = arg;
4753b2aab1Matthew Ahrens	dsl_pool_t *dp = dmu_tx_pool(tx);
4763b2aab1Matthew Ahrens	nvpair_t *pair;
4773b2aab1Matthew Ahrens
4783b2aab1Matthew Ahrens	for (pair = nvlist_next_nvpair(dsda->dsda_successful_snaps, NULL);
4793b2aab1Matthew Ahrens	    pair != NULL;
4803b2aab1Matthew Ahrens	    pair = nvlist_next_nvpair(dsda->dsda_successful_snaps, pair)) {
4813b2aab1Matthew Ahrens		dsl_dataset_t *ds;
4823b2aab1Matthew Ahrens
4833b2aab1Matthew Ahrens		VERIFY0(dsl_dataset_hold(dp, nvpair_name(pair), FTAG, &ds));
4843b2aab1Matthew Ahrens
4853b2aab1Matthew Ahrens		dsl_destroy_snapshot_sync_impl(ds, dsda->dsda_defer, tx);
4863b2aab1Matthew Ahrens		dsl_dataset_rele(ds, FTAG);
4873b2aab1Matthew Ahrens	}
4883b2aab1Matthew Ahrens}
4893b2aab1Matthew Ahrens
4903b2aab1Matthew Ahrens/*
4913b2aab1Matthew Ahrens * The semantics of this function are described in the comment above
4923b2aab1Matthew Ahrens * lzc_destroy_snaps().  To summarize:
4933b2aab1Matthew Ahrens *
4943b2aab1Matthew Ahrens * The snapshots must all be in the same pool.
4953b2aab1Matthew Ahrens *
4963b2aab1Matthew Ahrens * Snapshots that don't exist will be silently ignored (considered to be
4973b2aab1Matthew Ahrens * "already deleted").
4983b2aab1Matthew Ahrens *
4993b2aab1Matthew Ahrens * On success, all snaps will be destroyed and this will return 0.
5003b2aab1Matthew Ahrens * On failure, no snaps will be destroyed, the errlist will be filled in,
5013b2aab1Matthew Ahrens * and this will return an errno.
5023b2aab1Matthew Ahrens */
5033b2aab1Matthew Ahrensint
5043b2aab1Matthew Ahrensdsl_destroy_snapshots_nvl(nvlist_t *snaps, boolean_t defer,
5053b2aab1Matthew Ahrens    nvlist_t *errlist)
5063b2aab1Matthew Ahrens{
5073b2aab1Matthew Ahrens	dmu_snapshots_destroy_arg_t dsda;
5083b2aab1Matthew Ahrens	int error;
5093b2aab1Matthew Ahrens	nvpair_t *pair;
5103b2aab1Matthew Ahrens
5113b2aab1Matthew Ahrens	pair = nvlist_next_nvpair(snaps, NULL);
5123b2aab1Matthew Ahrens	if (pair == NULL)
5133b2aab1Matthew Ahrens		return (0);
5143b2aab1Matthew Ahrens
5153b2aab1Matthew Ahrens	dsda.dsda_snaps = snaps;
5163b2aab1Matthew Ahrens	dsda.dsda_successful_snaps = fnvlist_alloc();
5173b2aab1Matthew Ahrens	dsda.dsda_defer = defer;
5183b2aab1Matthew Ahrens	dsda.dsda_errlist = errlist;
5193b2aab1Matthew Ahrens
5203b2aab1Matthew Ahrens	error = dsl_sync_task(nvpair_name(pair),
5213b2aab1Matthew Ahrens	    dsl_destroy_snapshot_check, dsl_destroy_snapshot_sync,
5227d46dc6Matthew Ahrens	    &dsda, 0, ZFS_SPACE_CHECK_NONE);
5233b2aab1Matthew Ahrens	fnvlist_free(dsda.dsda_successful_snaps);
5243b2aab1Matthew Ahrens
5253b2aab1Matthew Ahrens	return (error);
5263b2aab1Matthew Ahrens}
5273b2aab1Matthew Ahrens
5283b2aab1Matthew Ahrensint
5293b2aab1Matthew Ahrensdsl_destroy_snapshot(const char *name, boolean_t defer)
5303b2aab1Matthew Ahrens{
5313b2aab1Matthew Ahrens	int error;
5323b2aab1Matthew Ahrens	nvlist_t *nvl = fnvlist_alloc();
5333b2aab1Matthew Ahrens	nvlist_t *errlist = fnvlist_alloc();
5343b2aab1Matthew Ahrens
5353b2aab1Matthew Ahrens	fnvlist_add_boolean(nvl, name);
5363b2aab1Matthew Ahrens	error = dsl_destroy_snapshots_nvl(nvl, defer, errlist);
5373b2aab1Matthew Ahrens	fnvlist_free(errlist);
5383b2aab1Matthew Ahrens	fnvlist_free(nvl);
5393b2aab1Matthew Ahrens	return (error);
5403b2aab1Matthew Ahrens}
5413b2aab1Matthew Ahrens
5423b2aab1Matthew Ahrensstruct killarg {
5433b2aab1Matthew Ahrens	dsl_dataset_t *ds;
5443b2aab1Matthew Ahrens	dmu_tx_t *tx;
5453b2aab1Matthew Ahrens};
5463b2aab1Matthew Ahrens
5473b2aab1Matthew Ahrens/* ARGSUSED */
5483b2aab1Matthew Ahrensstatic int
5493b2aab1Matthew Ahrenskill_blkptr(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
5507802d7bMatthew Ahrens    const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
5513b2aab1Matthew Ahrens{
5523b2aab1Matthew Ahrens	struct killarg *ka = arg;
5533b2aab1Matthew Ahrens	dmu_tx_t *tx = ka->tx;
5543b2aab1Matthew Ahrens
555a2cdcddPaul Dagnelie	if (bp == NULL || BP_IS_HOLE(bp) || BP_IS_EMBEDDED(bp))
5563b2aab1Matthew Ahrens		return (0);
5573b2aab1Matthew Ahrens
5583b2aab1Matthew Ahrens	if (zb->zb_level == ZB_ZIL_LEVEL) {
5593b2aab1Matthew Ahrens		ASSERT(zilog != NULL);
5603b2aab1Matthew Ahrens		/*
5613b2aab1Matthew Ahrens		 * It's a block in the intent log.  It has no
5623b2aab1Matthew Ahrens		 * accounting, so just free it.
5633b2aab1Matthew Ahrens		 */
5643b2aab1Matthew Ahrens		dsl_free(ka->tx->tx_pool, ka->tx->tx_txg, bp);
5653b2aab1Matthew Ahrens	} else {
5663b2aab1Matthew Ahrens		ASSERT(zilog == NULL);
567c137962Justin T. Gibbs		ASSERT3U(bp->blk_birth, >,
568c137962Justin T. Gibbs		    dsl_dataset_phys(ka->ds)->ds_prev_snap_txg);
5693b2aab1Matthew Ahrens		(void) dsl_dataset_block_kill(ka->ds, bp, tx, B_FALSE);
5703b2aab1Matthew Ahrens	}
5713b2aab1Matthew Ahrens
5723b2aab1Matthew Ahrens	return (0);
5733b2aab1Matthew Ahrens}
5743b2aab1Matthew Ahrens
5753b2aab1Matthew Ahrensstatic void
5763b2aab1Matthew Ahrensold_synchronous_dataset_destroy(dsl_dataset_t *ds, dmu_tx_t *tx)
5773b2aab1Matthew Ahrens{
5783b2aab1Matthew Ahrens	struct killarg ka;
5793b2aab1Matthew Ahrens
5803b2aab1Matthew Ahrens	/*
5813b2aab1Matthew Ahrens	 * Free everything that we point to (that's born after
5823b2aab1Matthew Ahrens	 * the previous snapshot, if we are a clone)
5833b2aab1Matthew Ahrens	 *
5843b2aab1Matthew Ahrens	 * NB: this should be very quick, because we already
5853b2aab1Matthew Ahrens	 * freed all the objects in open context.
5863b2aab1Matthew Ahrens	 */
5873b2aab1Matthew Ahrens	ka.ds = ds;
5883b2aab1Matthew Ahrens	ka.tx = tx;
5893b2aab1Matthew Ahrens	VERIFY0(traverse_dataset(ds,
590c137962Justin T. Gibbs	    dsl_dataset_phys(ds)->ds_prev_snap_txg, TRAVERSE_POST,
5913b2aab1Matthew Ahrens	    kill_blkptr, &ka));
592c137962Justin T. Gibbs	ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) ||
593c137962Justin T. Gibbs	    dsl_dataset_phys(ds)->ds_unique_bytes == 0);
5943b2aab1Matthew Ahrens}
5953b2aab1Matthew Ahrens
5963b2aab1Matthew Ahrenstypedef struct dsl_destroy_head_arg {
5973b2aab1Matthew Ahrens	const char *ddha_name;
5983b2aab1Matthew Ahrens} dsl_destroy_head_arg_t;
5993b2aab1Matthew Ahrens
6003b2aab1Matthew Ahrensint
6013b2aab1Matthew Ahrensdsl_destroy_head_check_impl(dsl_dataset_t *ds, int expected_holds)
6023b2aab1Matthew Ahrens{
6033b2aab1Matthew Ahrens	int error;
6043b2aab1Matthew Ahrens	uint64_t count;
6053b2aab1Matthew Ahrens	objset_t *mos;
6063b2aab1Matthew Ahrens
607bc9014eJustin Gibbs	ASSERT(!ds->ds_is_snapshot);
608bc9014eJustin Gibbs	if (ds->ds_is_snapshot)
609be6fd75Matthew Ahrens		return (SET_ERROR(EINVAL));
6103b2aab1Matthew Ahrens
6113b2aab1Matthew Ahrens	if (refcount_count(&ds->ds_longholds) != expected_holds)
612be6fd75Matthew Ahrens		return (SET_ERROR(EBUSY));
6133b2aab1Matthew Ahrens
6143b2aab1Matthew Ahrens	mos = ds->ds_dir->dd_pool->dp_meta_objset;
6153b2aab1Matthew Ahrens
6163b2aab1Matthew Ahrens	/*
6173b2aab1Matthew Ahrens	 * Can't delete a head dataset if there are snapshots of it.
6183b2aab1Matthew Ahrens	 * (Except if the only snapshots are from the branch we cloned
6193b2aab1Matthew Ahrens	 * from.)
6203b2aab1Matthew Ahrens	 */
6213b2aab1Matthew Ahrens	if (ds->ds_prev != NULL &&
622c137962Justin T. Gibbs	    dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj == ds->ds_object)
623be6fd75Matthew Ahrens		return (SET_ERROR(EBUSY));
6243b2aab1Matthew Ahrens
6253b2aab1Matthew Ahrens	/*
6263b2aab1Matthew Ahrens	 * Can't delete if there are children of this fs.
6273b2aab1Matthew Ahrens	 */
6283b2aab1Matthew Ahrens	error = zap_count(mos,
629c137962Justin T. Gibbs	    dsl_dir_phys(ds->ds_dir)->dd_child_dir_zapobj, &count);
6303b2aab1Matthew Ahrens	if (error != 0)
6313b2aab1Matthew Ahrens		return (error);
6323b2aab1Matthew Ahrens	if (count != 0)
633be6fd75Matthew Ahrens		return (SET_ERROR(EEXIST));
6343b2aab1Matthew Ahrens
6353b2aab1Matthew Ahrens	if (dsl_dir_is_clone(ds->ds_dir) && DS_IS_DEFER_DESTROY(ds->ds_prev) &&
636c137962Justin T. Gibbs	    dsl_dataset_phys(ds->ds_prev)->ds_num_children == 2 &&
6373b2aab1Matthew Ahrens	    ds->ds_prev->ds_userrefs == 0) {
6383b2aab1Matthew Ahrens		/* We need to remove the origin snapshot as well. */
6393b2aab1Matthew Ahrens		if (!refcount_is_zero(&ds->ds_prev->ds_longholds))
640be6fd75Matthew Ahrens			return (SET_ERROR(EBUSY));
6413b2aab1Matthew Ahrens	}
6423b2aab1Matthew Ahrens	return (0);
6433b2aab1Matthew Ahrens}
6443b2aab1Matthew Ahrens
6453b2aab1Matthew Ahrensstatic int
6463b2aab1Matthew Ahrensdsl_destroy_head_check(void *arg, dmu_tx_t *tx)
6473b2aab1Matthew Ahrens{
6483b2aab1Matthew Ahrens	dsl_destroy_head_arg_t *ddha = arg;
6493b2aab1Matthew Ahrens	dsl_pool_t *dp = dmu_tx_pool(tx);
6503b2aab1Matthew Ahrens	dsl_dataset_t *ds;
6513b2aab1Matthew Ahrens	int error;
6523b2aab1Matthew Ahrens
6533b2aab1Matthew Ahrens	error = dsl_dataset_hold(dp, ddha->ddha_name, FTAG, &ds);
6543b2aab1Matthew Ahrens	if (error != 0)
6553b2aab1Matthew Ahrens		return (error);
6563b2aab1Matthew Ahrens
6573b2aab1Matthew Ahrens	error = dsl_destroy_head_check_impl(ds, 0);
6583b2aab1Matthew Ahrens	dsl_dataset_rele(ds, FTAG);
6593b2aab1Matthew Ahrens	return (error);
6603b2aab1Matthew Ahrens}
6613b2aab1Matthew Ahrens
6623b2aab1Matthew Ahrensstatic void
6633b2aab1Matthew Ahrensdsl_dir_destroy_sync(uint64_t ddobj, dmu_tx_t *tx)
6643b2aab1Matthew Ahrens{
6653b2aab1Matthew Ahrens	dsl_dir_t *dd;
6663b2aab1Matthew Ahrens	dsl_pool_t *dp = dmu_tx_pool(tx);
6673b2aab1Matthew Ahrens	objset_t *mos = dp->dp_meta_objset;
6683b2aab1Matthew Ahrens	dd_used_t t;
6693b2aab1Matthew Ahrens
6703b2aab1Matthew Ahrens	ASSERT(RRW_WRITE_HELD(&dmu_tx_pool(tx)->dp_config_rwlock));
6713b2aab1Matthew Ahrens
6723b2aab1Matthew Ahrens	VERIFY0(dsl_dir_hold_obj(dp, ddobj, NULL, FTAG, &dd));
6733b2aab1Matthew Ahrens
674c137962Justin T. Gibbs	ASSERT0(dsl_dir_phys(dd)->dd_head_dataset_obj);
6753b2aab1Matthew Ahrens
6763b2aab1Matthew Ahrens	/*
677a2afb61Jerry Jelinek	 * Decrement the filesystem count for all parent filesystems.
678a2afb61Jerry Jelinek	 *
679a2afb61Jerry Jelinek	 * When we receive an incremental stream into a filesystem that already
680a2afb61Jerry Jelinek	 * exists, a temporary clone is created.  We never count this temporary
681a2afb61Jerry Jelinek	 * clone, whose name begins with a '%'.
682a2afb61Jerry Jelinek	 */
683a2afb61Jerry Jelinek	if (dd->dd_myname[0] != '%' && dd->dd_parent != NULL)
684a2afb61Jerry Jelinek		dsl_fs_ss_count_adjust(dd->dd_parent, -1,
685a2afb61Jerry Jelinek		    DD_FIELD_FILESYSTEM_COUNT, tx);
686a2afb61Jerry Jelinek
687a2afb61Jerry Jelinek	/*
6883b2aab1Matthew Ahrens	 * Remove our reservation. The impl() routine avoids setting the
6893b2aab1Matthew Ahrens	 * actual property, which would require the (already destroyed) ds.
6903b2aab1Matthew Ahrens	 */
6913b2aab1Matthew Ahrens	dsl_dir_set_reservation_sync_impl(dd, 0, tx);
6923b2aab1Matthew Ahrens
693c137962Justin T. Gibbs	ASSERT0(dsl_dir_phys(dd)->dd_used_bytes);
694c137962Justin T. Gibbs	ASSERT0(dsl_dir_phys(dd)->dd_reserved);
6953b2aab1Matthew Ahrens	for (t = 0; t < DD_USED_NUM; t++)
696c137962Justin T. Gibbs		ASSERT0(dsl_dir_phys(dd)->dd_used_breakdown[t]);
6973b2aab1Matthew Ahrens
698c137962Justin T. Gibbs	VERIFY0(zap_destroy(mos, dsl_dir_phys(dd)->dd_child_dir_zapobj, tx));
699c137962Justin T. Gibbs	VERIFY0(zap_destroy(mos, dsl_dir_phys(dd)->dd_props_zapobj, tx));
700c137962Justin T. Gibbs	VERIFY0(dsl_deleg_destroy(mos, dsl_dir_phys(dd)->dd_deleg_zapobj, tx));
7013b2aab1Matthew Ahrens	VERIFY0(zap_remove(mos,
702c137962Justin T. Gibbs	    dsl_dir_phys(dd->dd_parent)->dd_child_dir_zapobj,
703c137962Justin T. Gibbs	    dd->dd_myname, tx));
7043b2aab1Matthew Ahrens
7053b2aab1Matthew Ahrens	dsl_dir_rele(dd, FTAG);
7062acef22Matthew Ahrens	dmu_object_free_zapified(mos, ddobj, tx);
7073b2aab1Matthew Ahrens}
7083b2aab1Matthew Ahrens
7093b2aab1Matthew Ahrensvoid
7103b2aab1Matthew Ahrensdsl_destroy_head_sync_impl(dsl_dataset_t *ds, dmu_tx_t *tx)
7113b2aab1Matthew Ahrens{
7123b2aab1Matthew Ahrens	dsl_pool_t *dp = dmu_tx_pool(tx);
7133b2aab1Matthew Ahrens	objset_t *mos = dp->dp_meta_objset;
7143b2aab1Matthew Ahrens	uint64_t obj, ddobj, prevobj = 0;
7153b2aab1Matthew Ahrens	boolean_t rmorigin;
7163b2aab1Matthew Ahrens
717c137962Justin T. Gibbs	ASSERT3U(dsl_dataset_phys(ds)->ds_num_children, <=, 1);
7183b2aab1Matthew Ahrens	ASSERT(ds->ds_prev == NULL ||
719c137962Justin T. Gibbs	    dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj != ds->ds_object);
720c137962Justin T. Gibbs	ASSERT3U(dsl_dataset_phys(ds)->ds_bp.blk_birth, <=, tx->tx_txg);
7213b2aab1Matthew Ahrens	ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
7223b2aab1Matthew Ahrens
7233b2aab1Matthew Ahrens	/* We need to log before removing it from the namespace. */
7243b2aab1Matthew Ahrens	spa_history_log_internal_ds(ds, "destroy", tx, "");
7253b2aab1Matthew Ahrens
7263b2aab1Matthew Ahrens	rmorigin = (dsl_dir_is_clone(ds->ds_dir) &&
7273b2aab1Matthew Ahrens	    DS_IS_DEFER_DESTROY(ds->ds_prev) &&
728c137962Justin T. Gibbs	    dsl_dataset_phys(ds->ds_prev)->ds_num_children == 2 &&
7293b2aab1Matthew Ahrens	    ds->ds_prev->ds_userrefs == 0);
7303b2aab1Matthew Ahrens
7315d7b4d4Matthew Ahrens	/* Remove our reservation. */
7323b2aab1Matthew Ahrens	if (ds->ds_reserved != 0) {
7333b2aab1Matthew Ahrens		dsl_dataset_set_refreservation_sync_impl(ds,
7343b2aab1Matthew Ahrens		    (ZPROP_SRC_NONE | ZPROP_SRC_LOCAL | ZPROP_SRC_RECEIVED),
7353b2aab1Matthew Ahrens		    0, tx);
7363b2aab1Matthew Ahrens		ASSERT0(ds->ds_reserved);
7373b2aab1Matthew Ahrens	}
7383b2aab1Matthew Ahrens
739b515258Matthew Ahrens	if (ds->ds_large_blocks)
740b515258Matthew Ahrens		spa_feature_decr(dp->dp_spa, SPA_FEATURE_LARGE_BLOCKS, tx);
741b515258Matthew Ahrens
7423b2aab1Matthew Ahrens	dsl_scan_ds_destroyed(ds, tx);
7433b2aab1Matthew Ahrens
7443b2aab1Matthew Ahrens	obj = ds->ds_object;
7453b2aab1Matthew Ahrens
746c137962Justin T. Gibbs	if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) {
7473b2aab1Matthew Ahrens		/* This is a clone */
7483b2aab1Matthew Ahrens		ASSERT(ds->ds_prev != NULL);
749c137962Justin T. Gibbs		ASSERT3U(dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj, !=,
750c137962Justin T. Gibbs		    obj);
751c137962Justin T. Gibbs		ASSERT0(dsl_dataset_phys(ds)->ds_next_snap_obj);
7523b2aab1Matthew Ahrens
7533b2aab1Matthew Ahrens		dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
754c137962Justin T. Gibbs		if (dsl_dataset_phys(ds->ds_prev)->ds_next_clones_obj != 0) {
7553b2aab1Matthew Ahrens			dsl_dataset_remove_from_next_clones(ds->ds_prev,
7563b2aab1Matthew Ahrens			    obj, tx);
7573b2aab1Matthew Ahrens		}
7583b2aab1Matthew Ahrens
759c137962Justin T. Gibbs		ASSERT3U(dsl_dataset_phys(ds->ds_prev)->ds_num_children, >, 1);
760c137962Justin T. Gibbs		dsl_dataset_phys(ds->ds_prev)->ds_num_children--;
7613b2aab1Matthew Ahrens	}
7623b2aab1Matthew Ahrens
7633b2aab1Matthew Ahrens	/*
7643b2aab1Matthew Ahrens	 * Destroy the deadlist.  Unless it's a clone, the
7653b2aab1Matthew Ahrens	 * deadlist should be empty.  (If it's a clone, it's
7663b2aab1Matthew Ahrens	 * safe to ignore the deadlist contents.)
7673b2aab1Matthew Ahrens	 */
7683b2aab1Matthew Ahrens	dsl_deadlist_close(&ds->ds_deadlist);
769c137962Justin T. Gibbs	dsl_deadlist_free(mos, dsl_dataset_phys(ds)->ds_deadlist_obj, tx);
7703b2aab1Matthew Ahrens	dmu_buf_will_dirty(ds->ds_dbuf, tx);
771c137962Justin T. Gibbs	dsl_dataset_phys(ds)->ds_deadlist_obj = 0;
7723b2aab1Matthew Ahrens
7732acef22Matthew Ahrens	objset_t *os;
7743b2aab1Matthew Ahrens	VERIFY0(dmu_objset_from_ds(ds, &os));
7753b2aab1Matthew Ahrens
7762acef22Matthew Ahrens	if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_ASYNC_DESTROY)) {
7773b2aab1Matthew Ahrens		old_synchronous_dataset_destroy(ds, tx);
7783b2aab1Matthew Ahrens	} else {
7793b2aab1Matthew Ahrens		/*
7803b2aab1Matthew Ahrens		 * Move the bptree into the pool's list of trees to
7813b2aab1Matthew Ahrens		 * clean up and update space accounting information.
7823b2aab1Matthew Ahrens		 */
7833b2aab1Matthew Ahrens		uint64_t used, comp, uncomp;
7843b2aab1Matthew Ahrens
7853b2aab1Matthew Ahrens		zil_destroy_sync(dmu_objset_zil(os), tx);
7863b2aab1Matthew Ahrens
7872acef22Matthew Ahrens		if (!spa_feature_is_active(dp->dp_spa,
7882acef22Matthew Ahrens		    SPA_FEATURE_ASYNC_DESTROY)) {
7894a92375George Wilson			dsl_scan_t *scn = dp->dp_scan;
7902acef22Matthew Ahrens			spa_feature_incr(dp->dp_spa, SPA_FEATURE_ASYNC_DESTROY,
7912acef22Matthew Ahrens			    tx);
7923b2aab1Matthew Ahrens			dp->dp_bptree_obj = bptree_alloc(mos, tx);
7933b2aab1Matthew Ahrens			VERIFY0(zap_add(mos,
7943b2aab1Matthew Ahrens			    DMU_POOL_DIRECTORY_OBJECT,
7953b2aab1Matthew Ahrens			    DMU_POOL_BPTREE_OBJ, sizeof (uint64_t), 1,
7963b2aab1Matthew Ahrens			    &dp->dp_bptree_obj, tx));
7974a92375George Wilson			ASSERT(!scn->scn_async_destroying);
7984a92375George Wilson			scn->scn_async_destroying = B_TRUE;
7993b2aab1Matthew Ahrens		}
8003b2aab1Matthew Ahrens
801c137962Justin T. Gibbs		used = dsl_dir_phys(ds->ds_dir)->dd_used_bytes;
802c137962Justin T. Gibbs		comp = dsl_dir_phys(ds->ds_dir)->dd_compressed_bytes;
803c137962Justin T. Gibbs		uncomp = dsl_dir_phys(ds->ds_dir)->dd_uncompressed_bytes;
8043b2aab1Matthew Ahrens
8053b2aab1Matthew Ahrens		ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) ||
806c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_unique_bytes == used);
8073b2aab1Matthew Ahrens
8083b2aab1Matthew Ahrens		bptree_add(mos, dp->dp_bptree_obj,
809c137962Justin T. Gibbs		    &dsl_dataset_phys(ds)->ds_bp,
810c137962Justin T. Gibbs		    dsl_dataset_phys(ds)->ds_prev_snap_txg,
8113b2aab1Matthew Ahrens		    used, comp, uncomp, tx);
8123b2aab1Matthew Ahrens		dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD,
8133b2aab1Matthew Ahrens		    -used, -comp, -uncomp, tx);
8143b2aab1Matthew Ahrens		dsl_dir_diduse_space(dp->dp_free_dir, DD_USED_HEAD,
815