diff options
Diffstat (limited to 'fs/bcachefs/btree_journal_iter.c')
| -rw-r--r-- | fs/bcachefs/btree_journal_iter.c | 830 |
1 files changed, 0 insertions, 830 deletions
diff --git a/fs/bcachefs/btree_journal_iter.c b/fs/bcachefs/btree_journal_iter.c deleted file mode 100644 index ea839560a136..000000000000 --- a/fs/bcachefs/btree_journal_iter.c +++ /dev/null @@ -1,830 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 - -#include "bcachefs.h" -#include "bkey_buf.h" -#include "bset.h" -#include "btree_cache.h" -#include "btree_journal_iter.h" -#include "journal_io.h" - -#include <linux/sort.h> - -/* - * For managing keys we read from the journal: until journal replay works normal - * btree lookups need to be able to find and return keys from the journal where - * they overwrite what's in the btree, so we have a special iterator and - * operations for the regular btree iter code to use: - */ - -static inline size_t pos_to_idx(struct journal_keys *keys, size_t pos) -{ - size_t gap_size = keys->size - keys->nr; - - BUG_ON(pos >= keys->gap && pos < keys->gap + gap_size); - - if (pos >= keys->gap) - pos -= gap_size; - return pos; -} - -static inline size_t idx_to_pos(struct journal_keys *keys, size_t idx) -{ - size_t gap_size = keys->size - keys->nr; - - if (idx >= keys->gap) - idx += gap_size; - return idx; -} - -static inline struct journal_key *idx_to_key(struct journal_keys *keys, size_t idx) -{ - return keys->data + idx_to_pos(keys, idx); -} - -static size_t __bch2_journal_key_search(struct journal_keys *keys, - enum btree_id id, unsigned level, - struct bpos pos) -{ - size_t l = 0, r = keys->nr, m; - - while (l < r) { - m = l + ((r - l) >> 1); - if (__journal_key_cmp(id, level, pos, idx_to_key(keys, m)) > 0) - l = m + 1; - else - r = m; - } - - BUG_ON(l < keys->nr && - __journal_key_cmp(id, level, pos, idx_to_key(keys, l)) > 0); - - BUG_ON(l && - __journal_key_cmp(id, level, pos, idx_to_key(keys, l - 1)) <= 0); - - return l; -} - -static size_t bch2_journal_key_search(struct journal_keys *keys, - enum btree_id id, unsigned level, - struct bpos pos) -{ - return idx_to_pos(keys, __bch2_journal_key_search(keys, id, level, pos)); -} - -/* Returns first non-overwritten key >= search key: */ -struct bkey_i *bch2_journal_keys_peek_max(struct bch_fs *c, enum btree_id btree_id, - unsigned level, struct bpos pos, - struct bpos end_pos, size_t *idx) -{ - struct journal_keys *keys = &c->journal_keys; - unsigned iters = 0; - struct journal_key *k; - - BUG_ON(*idx > keys->nr); -search: - if (!*idx) - *idx = __bch2_journal_key_search(keys, btree_id, level, pos); - - while (*idx && - __journal_key_cmp(btree_id, level, end_pos, idx_to_key(keys, *idx - 1)) <= 0) { - --(*idx); - iters++; - if (iters == 10) { - *idx = 0; - goto search; - } - } - - struct bkey_i *ret = NULL; - rcu_read_lock(); /* for overwritten_ranges */ - - while ((k = *idx < keys->nr ? idx_to_key(keys, *idx) : NULL)) { - if (__journal_key_cmp(btree_id, level, end_pos, k) < 0) - break; - - if (k->overwritten) { - if (k->overwritten_range) - *idx = rcu_dereference(k->overwritten_range)->end; - else - *idx += 1; - continue; - } - - if (__journal_key_cmp(btree_id, level, pos, k) <= 0) { - ret = k->k; - break; - } - - (*idx)++; - iters++; - if (iters == 10) { - *idx = 0; - rcu_read_unlock(); - goto search; - } - } - - rcu_read_unlock(); - return ret; -} - -struct bkey_i *bch2_journal_keys_peek_prev_min(struct bch_fs *c, enum btree_id btree_id, - unsigned level, struct bpos pos, - struct bpos end_pos, size_t *idx) -{ - struct journal_keys *keys = &c->journal_keys; - unsigned iters = 0; - struct journal_key *k; - - BUG_ON(*idx > keys->nr); - - if (!keys->nr) - return NULL; -search: - if (!*idx) - *idx = __bch2_journal_key_search(keys, btree_id, level, pos); - - while (*idx < keys->nr && - __journal_key_cmp(btree_id, level, end_pos, idx_to_key(keys, *idx)) >= 0) { - (*idx)++; - iters++; - if (iters == 10) { - *idx = 0; - goto search; - } - } - - if (*idx == keys->nr) - --(*idx); - - struct bkey_i *ret = NULL; - rcu_read_lock(); /* for overwritten_ranges */ - - while (true) { - k = idx_to_key(keys, *idx); - if (__journal_key_cmp(btree_id, level, end_pos, k) > 0) - break; - - if (k->overwritten) { - if (k->overwritten_range) - *idx = rcu_dereference(k->overwritten_range)->start; - if (!*idx) - break; - --(*idx); - continue; - } - - if (__journal_key_cmp(btree_id, level, pos, k) >= 0) { - ret = k->k; - break; - } - - if (!*idx) - break; - --(*idx); - iters++; - if (iters == 10) { - *idx = 0; - goto search; - } - } - - rcu_read_unlock(); - return ret; -} - -struct bkey_i *bch2_journal_keys_peek_slot(struct bch_fs *c, enum btree_id btree_id, - unsigned level, struct bpos pos) -{ - size_t idx = 0; - - return bch2_journal_keys_peek_max(c, btree_id, level, pos, pos, &idx); -} - -static void journal_iter_verify(struct journal_iter *iter) -{ -#ifdef CONFIG_BCACHEFS_DEBUG - struct journal_keys *keys = iter->keys; - size_t gap_size = keys->size - keys->nr; - - BUG_ON(iter->idx >= keys->gap && - iter->idx < keys->gap + gap_size); - - if (iter->idx < keys->size) { - struct journal_key *k = keys->data + iter->idx; - - int cmp = __journal_key_btree_cmp(iter->btree_id, iter->level, k); - BUG_ON(cmp > 0); - } -#endif -} - -static void journal_iters_fix(struct bch_fs *c) -{ - struct journal_keys *keys = &c->journal_keys; - /* The key we just inserted is immediately before the gap: */ - size_t gap_end = keys->gap + (keys->size - keys->nr); - struct journal_key *new_key = &keys->data[keys->gap - 1]; - struct journal_iter *iter; - - /* - * If an iterator points one after the key we just inserted, decrement - * the iterator so it points at the key we just inserted - if the - * decrement was unnecessary, bch2_btree_and_journal_iter_peek() will - * handle that: - */ - list_for_each_entry(iter, &c->journal_iters, list) { - journal_iter_verify(iter); - if (iter->idx == gap_end && - new_key->btree_id == iter->btree_id && - new_key->level == iter->level) - iter->idx = keys->gap - 1; - journal_iter_verify(iter); - } -} - -static void journal_iters_move_gap(struct bch_fs *c, size_t old_gap, size_t new_gap) -{ - struct journal_keys *keys = &c->journal_keys; - struct journal_iter *iter; - size_t gap_size = keys->size - keys->nr; - - list_for_each_entry(iter, &c->journal_iters, list) { - if (iter->idx > old_gap) - iter->idx -= gap_size; - if (iter->idx >= new_gap) - iter->idx += gap_size; - } -} - -int bch2_journal_key_insert_take(struct bch_fs *c, enum btree_id id, - unsigned level, struct bkey_i *k) -{ - struct journal_key n = { - .btree_id = id, - .level = level, - .k = k, - .allocated = true, - /* - * Ensure these keys are done last by journal replay, to unblock - * journal reclaim: - */ - .journal_seq = U64_MAX, - }; - struct journal_keys *keys = &c->journal_keys; - size_t idx = bch2_journal_key_search(keys, id, level, k->k.p); - - BUG_ON(test_bit(BCH_FS_rw, &c->flags)); - - if (idx < keys->size && - journal_key_cmp(&n, &keys->data[idx]) == 0) { - if (keys->data[idx].allocated) - kfree(keys->data[idx].k); - keys->data[idx] = n; - return 0; - } - - if (idx > keys->gap) - idx -= keys->size - keys->nr; - - size_t old_gap = keys->gap; - - if (keys->nr == keys->size) { - journal_iters_move_gap(c, old_gap, keys->size); - old_gap = keys->size; - - struct journal_keys new_keys = { - .nr = keys->nr, - .size = max_t(size_t, keys->size, 8) * 2, - }; - - new_keys.data = bch2_kvmalloc(new_keys.size * sizeof(new_keys.data[0]), GFP_KERNEL); - if (!new_keys.data) { - bch_err(c, "%s: error allocating new key array (size %zu)", - __func__, new_keys.size); - return bch_err_throw(c, ENOMEM_journal_key_insert); - } - - /* Since @keys was full, there was no gap: */ - memcpy(new_keys.data, keys->data, sizeof(keys->data[0]) * keys->nr); - kvfree(keys->data); - keys->data = new_keys.data; - keys->nr = new_keys.nr; - keys->size = new_keys.size; - - /* And now the gap is at the end: */ - keys->gap = keys->nr; - } - - journal_iters_move_gap(c, old_gap, idx); - - move_gap(keys, idx); - - keys->nr++; - keys->data[keys->gap++] = n; - - journal_iters_fix(c); - - return 0; -} - -/* - * Can only be used from the recovery thread while we're still RO - can't be - * used once we've got RW, as journal_keys is at that point used by multiple - * threads: - */ -int bch2_journal_key_insert(struct bch_fs *c, enum btree_id id, - unsigned level, struct bkey_i *k) -{ - struct bkey_i *n; - int ret; - - n = kmalloc(bkey_bytes(&k->k), GFP_KERNEL); - if (!n) - return bch_err_throw(c, ENOMEM_journal_key_insert); - - bkey_copy(n, k); - ret = bch2_journal_key_insert_take(c, id, level, n); - if (ret) - kfree(n); - return ret; -} - -int bch2_journal_key_delete(struct bch_fs *c, enum btree_id id, - unsigned level, struct bpos pos) -{ - struct bkey_i whiteout; - - bkey_init(&whiteout.k); - whiteout.k.p = pos; - - return bch2_journal_key_insert(c, id, level, &whiteout); -} - -bool bch2_key_deleted_in_journal(struct btree_trans *trans, enum btree_id btree, - unsigned level, struct bpos pos) -{ - struct journal_keys *keys = &trans->c->journal_keys; - size_t idx = bch2_journal_key_search(keys, btree, level, pos); - - if (!trans->journal_replay_not_finished) - return false; - - return (idx < keys->size && - keys->data[idx].btree_id == btree && - keys->data[idx].level == level && - bpos_eq(keys->data[idx].k->k.p, pos) && - bkey_deleted(&keys->data[idx].k->k)); -} - -static void __bch2_journal_key_overwritten(struct journal_keys *keys, size_t pos) -{ - struct journal_key *k = keys->data + pos; - size_t idx = pos_to_idx(keys, pos); - - k->overwritten = true; - - struct journal_key *prev = idx > 0 ? keys->data + idx_to_pos(keys, idx - 1) : NULL; - struct journal_key *next = idx + 1 < keys->nr ? keys->data + idx_to_pos(keys, idx + 1) : NULL; - - bool prev_overwritten = prev && prev->overwritten; - bool next_overwritten = next && next->overwritten; - - struct journal_key_range_overwritten *prev_range = - prev_overwritten ? prev->overwritten_range : NULL; - struct journal_key_range_overwritten *next_range = - next_overwritten ? next->overwritten_range : NULL; - - BUG_ON(prev_range && prev_range->end != idx); - BUG_ON(next_range && next_range->start != idx + 1); - - if (prev_range && next_range) { - prev_range->end = next_range->end; - - keys->data[pos].overwritten_range = prev_range; - for (size_t i = next_range->start; i < next_range->end; i++) { - struct journal_key *ip = keys->data + idx_to_pos(keys, i); - BUG_ON(ip->overwritten_range != next_range); - ip->overwritten_range = prev_range; - } - - kfree_rcu_mightsleep(next_range); - } else if (prev_range) { - prev_range->end++; - k->overwritten_range = prev_range; - if (next_overwritten) { - prev_range->end++; - next->overwritten_range = prev_range; - } - } else if (next_range) { - next_range->start--; - k->overwritten_range = next_range; - if (prev_overwritten) { - next_range->start--; - prev->overwritten_range = next_range; - } - } else if (prev_overwritten || next_overwritten) { - struct journal_key_range_overwritten *r = kmalloc(sizeof(*r), GFP_KERNEL); - if (!r) - return; - - r->start = idx - (size_t) prev_overwritten; - r->end = idx + 1 + (size_t) next_overwritten; - - rcu_assign_pointer(k->overwritten_range, r); - if (prev_overwritten) - prev->overwritten_range = r; - if (next_overwritten) - next->overwritten_range = r; - } -} - -void bch2_journal_key_overwritten(struct bch_fs *c, enum btree_id btree, - unsigned level, struct bpos pos) -{ - struct journal_keys *keys = &c->journal_keys; - size_t idx = bch2_journal_key_search(keys, btree, level, pos); - - if (idx < keys->size && - keys->data[idx].btree_id == btree && - keys->data[idx].level == level && - bpos_eq(keys->data[idx].k->k.p, pos) && - !keys->data[idx].overwritten) { - mutex_lock(&keys->overwrite_lock); - __bch2_journal_key_overwritten(keys, idx); - mutex_unlock(&keys->overwrite_lock); - } -} - -static void bch2_journal_iter_advance(struct journal_iter *iter) -{ - if (iter->idx < iter->keys->size) { - iter->idx++; - if (iter->idx == iter->keys->gap) - iter->idx += iter->keys->size - iter->keys->nr; - } -} - -static struct bkey_s_c bch2_journal_iter_peek(struct journal_iter *iter) -{ - journal_iter_verify(iter); - - guard(rcu)(); - while (iter->idx < iter->keys->size) { - struct journal_key *k = iter->keys->data + iter->idx; - - int cmp = __journal_key_btree_cmp(iter->btree_id, iter->level, k); - if (cmp < 0) - break; - BUG_ON(cmp); - - if (!k->overwritten) - return bkey_i_to_s_c(k->k); - - if (k->overwritten_range) - iter->idx = idx_to_pos(iter->keys, rcu_dereference(k->overwritten_range)->end); - else - bch2_journal_iter_advance(iter); - } - - return bkey_s_c_null; -} - -static void bch2_journal_iter_exit(struct journal_iter *iter) -{ - list_del(&iter->list); -} - -static void bch2_journal_iter_init(struct bch_fs *c, - struct journal_iter *iter, - enum btree_id id, unsigned level, - struct bpos pos) -{ - iter->btree_id = id; - iter->level = level; - iter->keys = &c->journal_keys; - iter->idx = bch2_journal_key_search(&c->journal_keys, id, level, pos); - - journal_iter_verify(iter); -} - -static struct bkey_s_c bch2_journal_iter_peek_btree(struct btree_and_journal_iter *iter) -{ - return bch2_btree_node_iter_peek_unpack(&iter->node_iter, - iter->b, &iter->unpacked); -} - -static void bch2_journal_iter_advance_btree(struct btree_and_journal_iter *iter) -{ - bch2_btree_node_iter_advance(&iter->node_iter, iter->b); -} - -void bch2_btree_and_journal_iter_advance(struct btree_and_journal_iter *iter) -{ - if (bpos_eq(iter->pos, SPOS_MAX)) - iter->at_end = true; - else - iter->pos = bpos_successor(iter->pos); -} - -static void btree_and_journal_iter_prefetch(struct btree_and_journal_iter *_iter) -{ - struct btree_and_journal_iter iter = *_iter; - struct bch_fs *c = iter.trans->c; - unsigned level = iter.journal.level; - struct bkey_buf tmp; - unsigned nr = test_bit(BCH_FS_started, &c->flags) - ? (level > 1 ? 0 : 2) - : (level > 1 ? 1 : 16); - - iter.prefetch = false; - iter.fail_if_too_many_whiteouts = true; - bch2_bkey_buf_init(&tmp); - - while (nr--) { - bch2_btree_and_journal_iter_advance(&iter); - struct bkey_s_c k = bch2_btree_and_journal_iter_peek(&iter); - if (!k.k) - break; - - bch2_bkey_buf_reassemble(&tmp, c, k); - bch2_btree_node_prefetch(iter.trans, NULL, tmp.k, iter.journal.btree_id, level - 1); - } - - bch2_bkey_buf_exit(&tmp, c); -} - -struct bkey_s_c bch2_btree_and_journal_iter_peek(struct btree_and_journal_iter *iter) -{ - struct bkey_s_c btree_k, journal_k = bkey_s_c_null, ret; - size_t iters = 0; - - if (iter->prefetch && iter->journal.level) - btree_and_journal_iter_prefetch(iter); -again: - if (iter->at_end) - return bkey_s_c_null; - - iters++; - - if (iters > 20 && iter->fail_if_too_many_whiteouts) - return bkey_s_c_null; - - while ((btree_k = bch2_journal_iter_peek_btree(iter)).k && - bpos_lt(btree_k.k->p, iter->pos)) - bch2_journal_iter_advance_btree(iter); - - if (iter->trans->journal_replay_not_finished) - while ((journal_k = bch2_journal_iter_peek(&iter->journal)).k && - bpos_lt(journal_k.k->p, iter->pos)) - bch2_journal_iter_advance(&iter->journal); - - ret = journal_k.k && - (!btree_k.k || bpos_le(journal_k.k->p, btree_k.k->p)) - ? journal_k - : btree_k; - - if (ret.k && iter->b && bpos_gt(ret.k->p, iter->b->data->max_key)) - ret = bkey_s_c_null; - - if (ret.k) { - iter->pos = ret.k->p; - if (bkey_deleted(ret.k)) { - bch2_btree_and_journal_iter_advance(iter); - goto again; - } - } else { - iter->pos = SPOS_MAX; - iter->at_end = true; - } - - return ret; -} - -void bch2_btree_and_journal_iter_exit(struct btree_and_journal_iter *iter) -{ - bch2_journal_iter_exit(&iter->journal); -} - -void __bch2_btree_and_journal_iter_init_node_iter(struct btree_trans *trans, - struct btree_and_journal_iter *iter, - struct btree *b, - struct btree_node_iter node_iter, - struct bpos pos) -{ - memset(iter, 0, sizeof(*iter)); - - iter->trans = trans; - iter->b = b; - iter->node_iter = node_iter; - iter->pos = b->data->min_key; - iter->at_end = false; - INIT_LIST_HEAD(&iter->journal.list); - - if (trans->journal_replay_not_finished) { - bch2_journal_iter_init(trans->c, &iter->journal, b->c.btree_id, b->c.level, pos); - if (!test_bit(BCH_FS_may_go_rw, &trans->c->flags)) - list_add(&iter->journal.list, &trans->c->journal_iters); - } -} - -/* - * this version is used by btree_gc before filesystem has gone RW and - * multithreaded, so uses the journal_iters list: - */ -void bch2_btree_and_journal_iter_init_node_iter(struct btree_trans *trans, - struct btree_and_journal_iter *iter, - struct btree *b) -{ - struct btree_node_iter node_iter; - - bch2_btree_node_iter_init_from_start(&node_iter, b); - __bch2_btree_and_journal_iter_init_node_iter(trans, iter, b, node_iter, b->data->min_key); -} - -/* sort and dedup all keys in the journal: */ - -/* - * When keys compare equal, oldest compares first: - */ -static int journal_sort_key_cmp(const void *_l, const void *_r) -{ - const struct journal_key *l = _l; - const struct journal_key *r = _r; - int rewind = l->rewind && r->rewind ? -1 : 1; - - return journal_key_cmp(l, r) ?: - ((cmp_int(l->journal_seq, r->journal_seq) ?: - cmp_int(l->journal_offset, r->journal_offset)) * rewind); -} - -void bch2_journal_keys_put(struct bch_fs *c) -{ - struct journal_keys *keys = &c->journal_keys; - - BUG_ON(atomic_read(&keys->ref) <= 0); - - if (!atomic_dec_and_test(&keys->ref)) - return; - - move_gap(keys, keys->nr); - - darray_for_each(*keys, i) { - if (i->overwritten_range && - (i == &darray_last(*keys) || - i->overwritten_range != i[1].overwritten_range)) - kfree(i->overwritten_range); - - if (i->allocated) - kfree(i->k); - } - - kvfree(keys->data); - keys->data = NULL; - keys->nr = keys->gap = keys->size = 0; - - struct journal_replay **i; - struct genradix_iter iter; - - genradix_for_each(&c->journal_entries, iter, i) - kvfree(*i); - genradix_free(&c->journal_entries); -} - -static void __journal_keys_sort(struct journal_keys *keys) -{ - sort_nonatomic(keys->data, keys->nr, sizeof(keys->data[0]), - journal_sort_key_cmp, NULL); - - cond_resched(); - - struct journal_key *dst = keys->data; - - darray_for_each(*keys, src) { - /* - * We don't accumulate accounting keys here because we have to - * compare each individual accounting key against the version in - * the btree during replay: - */ - if (src->k->k.type != KEY_TYPE_accounting && - src + 1 < &darray_top(*keys) && - !journal_key_cmp(src, src + 1)) - continue; - - *dst++ = *src; - } - - keys->nr = dst - keys->data; -} - -int bch2_journal_keys_sort(struct bch_fs *c) -{ - struct genradix_iter iter; - struct journal_replay *i, **_i; - struct journal_keys *keys = &c->journal_keys; - size_t nr_read = 0; - - u64 rewind_seq = c->opts.journal_rewind ?: U64_MAX; - - genradix_for_each(&c->journal_entries, iter, _i) { - i = *_i; - - if (journal_replay_ignore(i)) - continue; - - cond_resched(); - - vstruct_for_each(&i->j, entry) { - bool rewind = !entry->level && - !btree_id_is_alloc(entry->btree_id) && - le64_to_cpu(i->j.seq) >= rewind_seq; - - if (entry->type != (rewind - ? BCH_JSET_ENTRY_overwrite - : BCH_JSET_ENTRY_btree_keys)) - continue; - - if (!rewind && le64_to_cpu(i->j.seq) < c->journal_replay_seq_start) - continue; - - jset_entry_for_each_key(entry, k) { - struct journal_key n = (struct journal_key) { - .btree_id = entry->btree_id, - .level = entry->level, - .rewind = rewind, - .k = k, - .journal_seq = le64_to_cpu(i->j.seq), - .journal_offset = k->_data - i->j._data, - }; - - if (darray_push(keys, n)) { - __journal_keys_sort(keys); - - if (keys->nr * 8 > keys->size * 7) { - bch_err(c, "Too many journal keys for slowpath; have %zu compacted, buf size %zu, processed %zu keys at seq %llu", - keys->nr, keys->size, nr_read, le64_to_cpu(i->j.seq)); - return bch_err_throw(c, ENOMEM_journal_keys_sort); - } - - BUG_ON(darray_push(keys, n)); - } - - nr_read++; - } - } - } - - __journal_keys_sort(keys); - keys->gap = keys->nr; - - bch_verbose(c, "Journal keys: %zu read, %zu after sorting and compacting", nr_read, keys->nr); - return 0; -} - -void bch2_shoot_down_journal_keys(struct bch_fs *c, enum btree_id btree, - unsigned level_min, unsigned level_max, - struct bpos start, struct bpos end) -{ - struct journal_keys *keys = &c->journal_keys; - size_t dst = 0; - - move_gap(keys, keys->nr); - - darray_for_each(*keys, i) - if (!(i->btree_id == btree && - i->level >= level_min && - i->level <= level_max && - bpos_ge(i->k->k.p, start) && - bpos_le(i->k->k.p, end))) - keys->data[dst++] = *i; - keys->nr = keys->gap = dst; -} - -void bch2_journal_keys_dump(struct bch_fs *c) -{ - struct journal_keys *keys = &c->journal_keys; - struct printbuf buf = PRINTBUF; - - pr_info("%zu keys:", keys->nr); - - move_gap(keys, keys->nr); - - darray_for_each(*keys, i) { - printbuf_reset(&buf); - prt_printf(&buf, "btree="); - bch2_btree_id_to_text(&buf, i->btree_id); - prt_printf(&buf, " l=%u ", i->level); - bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(i->k)); - pr_err("%s", buf.buf); - } - printbuf_exit(&buf); -} - -void bch2_fs_journal_keys_init(struct bch_fs *c) -{ - struct journal_keys *keys = &c->journal_keys; - - atomic_set(&keys->ref, 1); - keys->initial_ref_held = true; - mutex_init(&keys->overwrite_lock); -} |