blob: b32929b3320c908c65750717ed36cfb585cdedd6 [file] [log] [blame]
/*
* 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, 2018 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 <sys/zfs_context.h>
#include <sys/dsl_userhold.h>
#include <sys/dsl_dataset.h>
#include <sys/dsl_synctask.h>
#include <sys/dsl_destroy.h>
#include <sys/dsl_bookmark.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>
#include <sys/dmu_impl.h>
#include <sys/zvol.h>
#include <sys/zcp.h>
#include <sys/dsl_deadlist.h>
#include <sys/zthr.h>
#include <sys/spa_impl.h>
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, boolean_t bp_freed, 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, bp_freed, 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);
}
typedef struct remaining_clones_key {
dsl_dataset_t *rck_clone;
list_node_t rck_node;
} remaining_clones_key_t;
static remaining_clones_key_t *
rck_alloc(dsl_dataset_t *clone)
{
remaining_clones_key_t *rck = kmem_alloc(sizeof (*rck), KM_SLEEP);
rck->rck_clone = clone;
return (rck);
}
static void
dsl_dir_remove_clones_key_impl(dsl_dir_t *dd, uint64_t mintxg, dmu_tx_t *tx,
list_t *stack, void *tag)
{
objset_t *mos = dd->dd_pool->dp_meta_objset;
/*
* 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(dd)->dd_clones == 0)
return;
zap_cursor_t *zc = kmem_alloc(sizeof (zap_cursor_t), KM_SLEEP);
zap_attribute_t *za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
for (zap_cursor_init(zc, mos, dsl_dir_phys(dd)->dd_clones);
zap_cursor_retrieve(zc, za) == 0;
zap_cursor_advance(zc)) {
dsl_dataset_t *clone;
VERIFY0(dsl_dataset_hold_obj(dd->dd_pool,
za->za_first_integer, tag, &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);
}
list_insert_head(stack, rck_alloc(clone));
} else {
dsl_dataset_rele(clone, tag);
}
}
zap_cursor_fini(zc);
kmem_free(za, sizeof (zap_attribute_t));
kmem_free(zc, sizeof (zap_cursor_t));
}
void
dsl_dir_remove_clones_key(dsl_dir_t *top_dd, uint64_t mintxg, dmu_tx_t *tx)
{
list_t stack;
list_create(&stack, sizeof (remaining_clones_key_t),
offsetof(remaining_clones_key_t, rck_node));
dsl_dir_remove_clones_key_impl(top_dd, mintxg, tx, &stack, FTAG);
for (remaining_clones_key_t *rck = list_remove_head(&stack);
rck != NULL; rck = list_remove_head(&stack)) {
dsl_dataset_t *clone = rck->rck_clone;
dsl_dir_t *clone_dir = clone->ds_dir;
kmem_free(rck, sizeof (*rck));
dsl_dir_remove_clones_key_impl(clone_dir, mintxg, tx,
&stack, FTAG);
dsl_dataset_rele(clone, FTAG);
}
list_destroy(&stack);
}
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(zfs_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;
}
}
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);
/*
* We are done with the deadlist tree (generated/used
* by dsl_deadlist_move_bpobj() and dsl_deadlist_merge()).
* Discard it to save memory.
*/
dsl_deadlist_discard_tree(&ds_next->ds_deadlist);
}
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);
if (!book_exists) {
/* Collapse range in clone heads */
dsl_dir_remove_clones_key(ds->ds_dir,
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));
if (!book_exists) {
/* Collapse range in this head. */
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) {
uint64_t count __maybe_unused;
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.
*/
nvlist_t *snaps_normalized = fnvlist_alloc();
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 = fnvlist_alloc();
fnvlist_add_nvlist(arg, "snaps", snaps_normalized);
fnvlist_free(snaps_normalized);
fnvlist_add_boolean_value(arg, "defer", defer);
nvlist_t *wrapper = fnvlist_alloc();
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,
fnvlist_lookup_nvpair(wrapper, ZCP_ARG_ARGLIST), result);
if (error != 0) {
char *errorstr = NULL;
(void) nvlist_lookup_string(result, ZCP_RET_ERROR, &errorstr);
if (errorstr != NULL) {
zfs_dbgmsg("%s", errorstr);
}
fnvlist_free(wrapper);
fnvlist_free(result);
return (error);
}
fnvlist_free(wrapper);
/*
* lzc_destroy_snaps() is documented to fill the errlist with
* int32 values, so we need to convert 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;
};
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)
{
(void) spa, (void) dnp;
struct killarg *ka = arg;
dmu_tx_t *tx = ka->tx;
if (zb->zb_level == ZB_DNODE_LEVEL || 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;
spa_history_log_internal_ds(ds, "destroy", tx,
"(synchronous, mintxg=%llu)",
(long long)dsl_dataset_phys(ds)->ds_prev_snap_txg);
/*
* 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 (zfs_refcount_count(&ds->ds_longholds) != expected_holds)
return (SET_ERROR(EBUSY));
ASSERT0(ds->ds_dir->dd_activity_waiters);
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 (!zfs_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. */
if (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));
if (dsl_dir_phys(dd)->dd_clones != 0)
VERIFY0(zap_destroy(mos, dsl_dir_phys(dd)->dd_clones, 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);
}
static void
dsl_clone_destroy_assert(dsl_dir_t *dd)
{
uint64_t used, comp, uncomp;
ASSERT(dsl_dir_is_clone(dd));
dsl_deadlist_space(&dd->dd_livelist, &used, &comp, &uncomp);
ASSERT3U(dsl_dir_phys(dd)->dd_used_bytes, ==, used);
ASSERT3U(dsl_dir_phys(dd)->dd_compressed_bytes, ==, comp);
/*
* Greater than because we do not track embedded block pointers in
* the livelist
*/
ASSERT3U(dsl_dir_phys(dd)->dd_uncompressed_bytes, >=, uncomp);
ASSERT(list_is_empty(&dd->dd_pending_allocs.bpl_list));
ASSERT(list_is_empty(&dd->dd_pending_frees.bpl_list));
}
/*
* Start the delete process for a clone. Free its zil, verify the space usage
* and queue the blkptrs for deletion by adding the livelist to the pool-wide
* delete queue.
*/
static void
dsl_async_clone_destroy(dsl_dataset_t *ds, dmu_tx_t *tx)
{
uint64_t zap_obj, to_delete, used, comp, uncomp;
objset_t *os;
dsl_dir_t *dd = ds->ds_dir;
dsl_pool_t *dp = dmu_tx_pool(tx);
objset_t *mos = dp->dp_meta_objset;
spa_t *spa = dmu_tx_pool(tx)->dp_spa;
VERIFY0(dmu_objset_from_ds(ds, &os));
uint64_t mintxg = 0;
dsl_deadlist_entry_t *dle = dsl_deadlist_first(&dd->dd_livelist);
if (dle != NULL)
mintxg = dle->dle_mintxg;
spa_history_log_internal_ds(ds, "destroy", tx,
"(livelist, mintxg=%llu)", (long long)mintxg);
/* Check that the clone is in a correct state to be deleted */
dsl_clone_destroy_assert(dd);
/* Destroy the zil */
zil_destroy_sync(dmu_objset_zil(os), tx);
VERIFY0(zap_lookup(mos, dd->dd_object,
DD_FIELD_LIVELIST, sizeof (uint64_t), 1, &to_delete));
/* Initialize deleted_clones entry to track livelists to cleanup */
int error = zap_lookup(mos, DMU_POOL_DIRECTORY_OBJECT,
DMU_POOL_DELETED_CLONES, sizeof (uint64_t), 1, &zap_obj);
if (error == ENOENT) {
zap_obj = zap_create(mos, DMU_OTN_ZAP_METADATA,
DMU_OT_NONE, 0, tx);
VERIFY0(zap_add(mos, DMU_POOL_DIRECTORY_OBJECT,
DMU_POOL_DELETED_CLONES, sizeof (uint64_t), 1,
&(zap_obj), tx));
spa->spa_livelists_to_delete = zap_obj;
} else if (error != 0) {
zfs_panic_recover("zfs: error %d was returned while looking "
"up DMU_POOL_DELETED_CLONES in the zap", error);
return;
}
VERIFY0(zap_add_int(mos, zap_obj, to_delete, tx));
/* Clone is no longer using space, now tracked by dp_free_dir */
dsl_deadlist_space(&dd->dd_livelist, &used, &comp, &uncomp);
dsl_dir_diduse_space(dd, DD_USED_HEAD,
-used, -comp, -dsl_dir_phys(dd)->dd_uncompressed_bytes,
tx);
dsl_dir_diduse_space(dp->dp_free_dir, DD_USED_HEAD,
used, comp, uncomp, tx);
dsl_dir_remove_livelist(dd, tx, B_FALSE);
zthr_wakeup(spa->spa_livelist_delete_zthr);
}
/*
* Move the bptree into the pool's list of trees to clean up, update space
* accounting information and destroy the zil.
*/
static void
dsl_async_dataset_destroy(dsl_dataset_t *ds, dmu_tx_t *tx)
{
uint64_t used, comp, uncomp;
objset_t *os;
VERIFY0(dmu_objset_from_ds(ds, &os));
dsl_pool_t *dp = dmu_tx_pool(tx);
objset_t *mos = dp->dp_meta_objset;
spa_history_log_internal_ds(ds, "destroy", tx,
"(bptree, mintxg=%llu)",
(long long)dsl_dataset_phys(ds)->ds_prev_snap_txg);
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);
}
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));
dsl_dir_cancel_waiters(ds->ds_dir);
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 (dsl_dataset_feature_is_active(ds, f))
dsl_dataset_deactivate_feature(ds, f, tx);
}
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);
/*
* Each destroy is responsible for both destroying (enqueuing
* to be destroyed) the blkptrs comprising the dataset as well as
* those belonging to the zil.
*/
if (dsl_deadlist_is_open(&ds->ds_dir->dd_livelist)) {
dsl_async_clone_destroy(ds, tx);
} else if (spa_feature_is_enabled(dp->dp_spa,
SPA_FEATURE_ASYNC_DESTROY)) {
dsl_async_dataset_destroy(ds, tx);
} else {
old_synchronous_dataset_destroy(ds, 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_obj != 0) {
void *cookie = NULL;
dsl_bookmark_node_t *dbn;
while ((dbn = avl_destroy_nodes(&ds->ds_bookmarks, &cookie)) !=
NULL) {
if (dbn->dbn_phys.zbm_redaction_obj != 0) {
VERIFY0(dmu_object_free(mos,
dbn->dbn_phys.zbm_redaction_obj, tx));
spa_feature_decr(dmu_objset_spa(mos),
SPA_FEATURE_REDACTION_BOOKMARKS, tx);
}
if (dbn->dbn_phys.zbm_flags & ZBM_FLAG_HAS_FBN) {
spa_feature_decr(dmu_objset_spa(mos),
SPA_FEATURE_BOOKMARK_WRITTEN, tx);
}
spa_strfree(dbn->dbn_name);
mutex_destroy(&dbn->dbn_lock);
kmem_free(dbn, sizeof (*dbn));
}
avl_destroy(&ds->ds_bookmarks);
VERIFY0(zap_destroy(mos, ds->ds_bookmarks_obj, 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. This optimization can only work for
* encrypted datasets if the wrapping key is loaded.
*/
error = dmu_objset_own(name, DMU_OST_ANY, B_FALSE, B_TRUE,
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_TRUE, 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.
*/
int
dsl_destroy_inconsistent(const char *dsname, void *arg)
{
(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