mirror_zfs/module/zfs/dsl_destroy.c
George Wilson 493fcce9be
Provide macros for setting and getting blkptr birth times
There exist a couple of macros that are used to update the blkptr birth
times but they can often be confusing. For example, the
BP_PHYSICAL_BIRTH() macro will provide either the physical birth time
if it is set or else return back the logical birth time. The
complement to this macro is BP_SET_BIRTH() which will set the logical
birth time and set the physical birth time if they are not the same.
Consumers may get confused when they are trying to get the physical
birth time and use the BP_PHYSICAL_BIRTH() macro only to find out that
the logical birth time is what is actually returned.

This change cleans up these macros and makes them symmetrical. The same
functionally is preserved but the name is changed. Instead of calling
BP_PHYSICAL_BIRTH(), consumer can now call BP_GET_BIRTH(). In
additional to cleaning up this naming conventions, two new sets of
macros are introduced -- BP_[SET|GET]_LOGICAL_BIRTH() and
BP_[SET|GET]_PHYSICAL_BIRTH.  These new macros allow the consumer to
get and set the specific birth time.

As part of the cleanup, the unused GRID macros have been removed and
that portion of the blkptr are currently unused.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Signed-off-by: George Wilson <gwilson@delphix.com>
Closes #15962
2024-03-25 15:01:54 -07:00

1305 lines
37 KiB
C

/*
* 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 https://opensource.org/licenses/CDDL-1.0.
* 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>
extern int zfs_snapshot_history_enabled;
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_GET_LOGICAL_BIRTH(bp) <=
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_GET_LOGICAL_BIRTH(bp) >
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, const 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(BP_GET_LOGICAL_BIRTH(&dsl_dataset_phys(ds)->ds_bp), <=,
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;
if (zfs_snapshot_history_enabled) {
spa_history_log_internal_ds(ds, "defer_destroy", tx,
" ");
}
return;
}
ASSERT3U(dsl_dataset_phys(ds)->ds_num_children, <=, 1);
if (zfs_snapshot_history_enabled) {
/* 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) {
const 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_GET_LOGICAL_BIRTH(bp), >,
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(BP_GET_LOGICAL_BIRTH(&dsl_dataset_phys(ds)->ds_bp), <=,
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) {
dnode_t *rl;
VERIFY0(dnode_hold(mos,
dbn->dbn_phys.zbm_redaction_obj, FTAG,
&rl));
if (rl->dn_have_spill) {
spa_feature_decr(dmu_objset_spa(mos),
SPA_FEATURE_REDACTION_LIST_SPILL,
tx);
}
dnode_rele(rl, FTAG);
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);
}
/* Delete errlog. */
if (spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_HEAD_ERRLOG))
spa_delete_dataset_errlog(dp->dp_spa, ds->ds_object, tx);
}
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