void
rrw_enter_read(rrwlock_t *rrl, void *tag)
{
mutex_enter(&rrl->rr_lock);
#if !defined(DEBUG) && defined(_KERNEL)
if (rrl->rr_writer == NULL && !rrl->rr_writer_wanted &&
!rrl->rr_track_all) {
rrl->rr_anon_rcount.rc_count++;
mutex_exit(&rrl->rr_lock);
return;
}
DTRACE_PROBE(zfs__rrwfastpath__rdmiss);
#endif
ASSERT(rrl->rr_writer != curthread);
ASSERT(refcount_count(&rrl->rr_anon_rcount) >= 0);
while (rrl->rr_writer != NULL || (rrl->rr_writer_wanted &&
refcount_is_zero(&rrl->rr_anon_rcount) &&
rrn_find(rrl) == NULL))
cv_wait(&rrl->rr_cv, &rrl->rr_lock);
if (rrl->rr_writer_wanted || rrl->rr_track_all) {
/* may or may not be a re-entrant enter */
rrn_add(rrl, tag);
(void) refcount_add(&rrl->rr_linked_rcount, tag);
} else {
(void) refcount_add(&rrl->rr_anon_rcount, tag);
}
ASSERT(rrl->rr_writer == NULL);
mutex_exit(&rrl->rr_lock);
}
void
dsl_destroy_snapshot_sync_impl(dsl_dataset_t *ds, boolean_t defer, dmu_tx_t *tx)
{
#ifdef ZFS_DEBUG
int err;
#endif
int after_branch_point = FALSE;
dsl_pool_t *dp = ds->ds_dir->dd_pool;
objset_t *mos = dp->dp_meta_objset;
dsl_dataset_t *ds_prev = NULL;
uint64_t obj, old_unique, used = 0, comp = 0, uncomp = 0;
dsl_dataset_t *ds_next, *ds_head, *hds;
ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg);
ASSERT(refcount_is_zero(&ds->ds_longholds));
if (defer &&
(ds->ds_userrefs > 0 || ds->ds_phys->ds_num_children > 1)) {
ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS);
dmu_buf_will_dirty(ds->ds_dbuf, tx);
ds->ds_phys->ds_flags |= DS_FLAG_DEFER_DESTROY;
spa_history_log_internal_ds(ds, "defer_destroy", tx, "");
return;
}
ASSERT3U(ds->ds_phys->ds_num_children, <=, 1);
/* We need to log before removing it from the namespace. */
spa_history_log_internal_ds(ds, "destroy", tx, "");
dsl_scan_ds_destroyed(ds, tx);
obj = ds->ds_object;
if (ds->ds_phys->ds_prev_snap_obj != 0) {
ASSERT3P(ds->ds_prev, ==, NULL);
VERIFY0(dsl_dataset_hold_obj(dp,
ds->ds_phys->ds_prev_snap_obj, FTAG, &ds_prev));
after_branch_point =
(ds_prev->ds_phys->ds_next_snap_obj != obj);
dmu_buf_will_dirty(ds_prev->ds_dbuf, tx);
if (after_branch_point &&
ds_prev->ds_phys->ds_next_clones_obj != 0) {
dsl_dataset_remove_from_next_clones(ds_prev, obj, tx);
if (ds->ds_phys->ds_next_snap_obj != 0) {
VERIFY0(zap_add_int(mos,
ds_prev->ds_phys->ds_next_clones_obj,
ds->ds_phys->ds_next_snap_obj, tx));
}
}
if (!after_branch_point) {
ds_prev->ds_phys->ds_next_snap_obj =
ds->ds_phys->ds_next_snap_obj;
}
}
void
rrw_exit(rrwlock_t *rrl, void *tag)
{
mutex_enter(&rrl->rr_lock);
#if !defined(DEBUG) && defined(_KERNEL)
if (!rrl->rr_writer && rrl->rr_linked_rcount.rc_count == 0) {
rrl->rr_anon_rcount.rc_count--;
if (rrl->rr_anon_rcount.rc_count == 0)
cv_broadcast(&rrl->rr_cv);
mutex_exit(&rrl->rr_lock);
return;
}
DTRACE_PROBE(zfs__rrwfastpath__exitmiss);
#endif
ASSERT(!refcount_is_zero(&rrl->rr_anon_rcount) ||
!refcount_is_zero(&rrl->rr_linked_rcount) ||
rrl->rr_writer != NULL);
if (rrl->rr_writer == NULL) {
int64_t count;
if (rrn_find_and_remove(rrl, tag)) {
count = refcount_remove(&rrl->rr_linked_rcount, tag);
} else {
ASSERT(!rrl->rr_track_all);
count = refcount_remove(&rrl->rr_anon_rcount, tag);
}
if (count == 0)
cv_broadcast(&rrl->rr_cv);
} else {
ASSERT(rrl->rr_writer == curthread);
ASSERT(refcount_is_zero(&rrl->rr_anon_rcount) &&
refcount_is_zero(&rrl->rr_linked_rcount));
rrl->rr_writer = NULL;
cv_broadcast(&rrl->rr_cv);
}
mutex_exit(&rrl->rr_lock);
}
/*
* If the lock was created with track_all, rrw_held(RW_READER) will return
* B_TRUE iff the current thread has the lock for reader. Otherwise it may
* return B_TRUE if any thread has the lock for reader.
*/
boolean_t
rrw_held(rrwlock_t *rrl, krw_t rw)
{
boolean_t held;
mutex_enter(&rrl->rr_lock);
if (rw == RW_WRITER) {
held = (rrl->rr_writer == curthread);
} else {
held = (!refcount_is_zero(&rrl->rr_anon_rcount) ||
rrn_find(rrl) != NULL);
}
mutex_exit(&rrl->rr_lock);
return (held);
}
static int
zcrypt_keychain_fini(avl_tree_t keychain)
{
void *cookie = NULL;
zcrypt_keychain_node_t *node = NULL;
#if 0
while (AVL_NEXT(&keychain, node) != NULL) {
if (!refcount_is_zero(&node->dkn_key->zk_refcnt))
return (EBUSY);
}
#endif
while ((node = avl_destroy_nodes(&keychain, &cookie)) != NULL) {
zcrypt_key_free(node->dkn_key);
kmem_free(node, sizeof (zcrypt_keychain_node_t));
}
avl_destroy(&keychain);
return (0);
}
void
dsl_destroy_snapshot_sync_impl(dsl_dataset_t *ds, boolean_t defer, dmu_tx_t *tx)
{
int err;
int after_branch_point = FALSE;
dsl_pool_t *dp = ds->ds_dir->dd_pool;
objset_t *mos = dp->dp_meta_objset;
dsl_dataset_t *ds_prev = NULL;
uint64_t obj;
ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
ASSERT3U(dsl_dataset_phys(ds)->ds_bp.blk_birth, <=, tx->tx_txg);
rrw_exit(&ds->ds_bp_rwlock, FTAG);
ASSERT(refcount_is_zero(&ds->ds_longholds));
if (defer &&
(ds->ds_userrefs > 0 ||
dsl_dataset_phys(ds)->ds_num_children > 1)) {
ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS);
dmu_buf_will_dirty(ds->ds_dbuf, tx);
dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_DEFER_DESTROY;
spa_history_log_internal_ds(ds, "defer_destroy", tx, "");
return;
}
ASSERT3U(dsl_dataset_phys(ds)->ds_num_children, <=, 1);
/* We need to log before removing it from the namespace. */
spa_history_log_internal_ds(ds, "destroy", tx, "");
dsl_scan_ds_destroyed(ds, tx);
obj = ds->ds_object;
boolean_t book_exists = dsl_bookmark_ds_destroyed(ds, tx);
for (spa_feature_t f = 0; f < SPA_FEATURES; f++) {
if (dsl_dataset_feature_is_active(ds, f))
dsl_dataset_deactivate_feature(ds, f, tx);
}
if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) {
ASSERT3P(ds->ds_prev, ==, NULL);
VERIFY0(dsl_dataset_hold_obj(dp,
dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &ds_prev));
after_branch_point =
(dsl_dataset_phys(ds_prev)->ds_next_snap_obj != obj);
dmu_buf_will_dirty(ds_prev->ds_dbuf, tx);
if (after_branch_point &&
dsl_dataset_phys(ds_prev)->ds_next_clones_obj != 0) {
dsl_dataset_remove_from_next_clones(ds_prev, obj, tx);
if (dsl_dataset_phys(ds)->ds_next_snap_obj != 0) {
VERIFY0(zap_add_int(mos,
dsl_dataset_phys(ds_prev)->
ds_next_clones_obj,
dsl_dataset_phys(ds)->ds_next_snap_obj,
tx));
}
}
if (!after_branch_point) {
dsl_dataset_phys(ds_prev)->ds_next_snap_obj =
dsl_dataset_phys(ds)->ds_next_snap_obj;
}
}