1 files changed, 357 insertions, 77 deletions

diff --git a/fs/bcachefs/btree_journal_iter.c b/fs/bcachefs/btree_journal_iter.c
index 50e04356d72c..ea839560a136 100644
--- a/fs/bcachefs/btree_journal_iter.c
+++ b/fs/bcachefs/btree_journal_iter.c
@@ -16,19 +16,15 @@
  * operations for the regular btree iter code to use:
  */
 
-static int __journal_key_cmp(enum btree_id	l_btree_id,
-			     unsigned		l_level,
-			     struct bpos	l_pos,
-			     const struct journal_key *r)
+static inline size_t pos_to_idx(struct journal_keys *keys, size_t pos)
 {
-	return (cmp_int(l_btree_id,	r->btree_id) ?:
-		cmp_int(l_level,	r->level) ?:
-		bpos_cmp(l_pos,	r->k->k.p));
-}
+	size_t gap_size = keys->size - keys->nr;
 
-static int journal_key_cmp(const struct journal_key *l, const struct journal_key *r)
-{
-	return __journal_key_cmp(l->btree_id, l->level, l->k->k.p, r);
+	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)
@@ -76,7 +72,7 @@ static size_t bch2_journal_key_search(struct journal_keys *keys,
 }
 
 /* Returns first non-overwritten key >= search key: */
-struct bkey_i *bch2_journal_keys_peek_upto(struct bch_fs *c, enum btree_id btree_id,
+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)
 {
@@ -99,27 +95,102 @@ 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)
-			return NULL;
+			break;
 
 		if (k->overwritten) {
-			(*idx)++;
+			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)
-			return k->k;
+		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;
 		}
 	}
 
-	return NULL;
+	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,
@@ -127,7 +198,25 @@ struct bkey_i *bch2_journal_keys_peek_slot(struct bch_fs *c, enum btree_id btree
 {
 	size_t idx = 0;
 
-	return bch2_journal_keys_peek_upto(c, btree_id, level, pos, pos, &idx);
+	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)
@@ -135,7 +224,8 @@ 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 btree_and_journal_iter *iter;
+	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
@@ -143,9 +233,14 @@ static void journal_iters_fix(struct bch_fs *c)
 	 * decrement was unnecessary, bch2_btree_and_journal_iter_peek() will
 	 * handle that:
 	 */
-	list_for_each_entry(iter, &c->journal_iters, journal.list)
-		if (iter->journal.idx == gap_end)
-			iter->journal.idx = keys->gap - 1;
+	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)
@@ -174,7 +269,7 @@ int bch2_journal_key_insert_take(struct bch_fs *c, enum btree_id id,
 		 * Ensure these keys are done last by journal replay, to unblock
 		 * journal reclaim:
 		 */
-		.journal_seq	= U32_MAX,
+		.journal_seq	= U64_MAX,
 	};
 	struct journal_keys *keys = &c->journal_keys;
 	size_t idx = bch2_journal_key_search(keys, id, level, k->k.p);
@@ -192,17 +287,22 @@ int bch2_journal_key_insert_take(struct bch_fs *c, enum btree_id id,
 	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 = kvmalloc_array(new_keys.size, sizeof(new_keys.data[0]), GFP_KERNEL);
+		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_ENOMEM_journal_key_insert;
+			return bch_err_throw(c, ENOMEM_journal_key_insert);
 		}
 
 		/* Since @keys was full, there was no gap: */
@@ -216,7 +316,7 @@ int bch2_journal_key_insert_take(struct bch_fs *c, enum btree_id id,
 		keys->gap	= keys->nr;
 	}
 
-	journal_iters_move_gap(c, keys->gap, idx);
+	journal_iters_move_gap(c, old_gap, idx);
 
 	move_gap(keys, idx);
 
@@ -241,7 +341,7 @@ int bch2_journal_key_insert(struct bch_fs *c, enum btree_id id,
 
 	n = kmalloc(bkey_bytes(&k->k), GFP_KERNEL);
 	if (!n)
-		return -BCH_ERR_ENOMEM_journal_key_insert;
+		return bch_err_throw(c, ENOMEM_journal_key_insert);
 
 	bkey_copy(n, k);
 	ret = bch2_journal_key_insert_take(c, id, level, n);
@@ -261,6 +361,84 @@ int bch2_journal_key_delete(struct bch_fs *c, enum btree_id id,
 	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)
 {
@@ -270,8 +448,12 @@ void bch2_journal_key_overwritten(struct bch_fs *c, enum btree_id btree,
 	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 = true;
+	    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)
@@ -285,16 +467,24 @@ static void bch2_journal_iter_advance(struct journal_iter *iter)
 
 static struct bkey_s_c bch2_journal_iter_peek(struct journal_iter *iter)
 {
-	struct journal_key *k = iter->keys->data + iter->idx;
+	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);
 
-	while (k < iter->keys->data + iter->keys->size &&
-	       k->btree_id	== iter->btree_id &&
-	       k->level		== iter->level) {
 		if (!k->overwritten)
 			return bkey_i_to_s_c(k->k);
 
-		bch2_journal_iter_advance(iter);
-		k = iter->keys->data + iter->idx;
+		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;
@@ -314,6 +504,8 @@ static void bch2_journal_iter_init(struct bch_fs *c,
 	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)
@@ -346,6 +538,7 @@ static void btree_and_journal_iter_prefetch(struct btree_and_journal_iter *_iter
 		: (level > 1 ? 1 : 16);
 
 	iter.prefetch = false;
+	iter.fail_if_too_many_whiteouts = true;
 	bch2_bkey_buf_init(&tmp);
 
 	while (nr--) {
@@ -363,7 +556,8 @@ static void btree_and_journal_iter_prefetch(struct btree_and_journal_iter *_iter
 
 struct bkey_s_c bch2_btree_and_journal_iter_peek(struct btree_and_journal_iter *iter)
 {
-	struct bkey_s_c btree_k, journal_k, ret;
+	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);
@@ -371,13 +565,19 @@ 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);
 
-	while ((journal_k = bch2_journal_iter_peek(&iter->journal)).k &&
-	       bpos_lt(journal_k.k->p, iter->pos))
-		bch2_journal_iter_advance(&iter->journal);
+	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))
@@ -417,10 +617,15 @@ void __bch2_btree_and_journal_iter_init_node_iter(struct btree_trans *trans,
 	iter->trans = trans;
 	iter->b = b;
 	iter->node_iter = node_iter;
-	bch2_journal_iter_init(trans->c, &iter->journal, b->c.btree_id, b->c.level, pos);
-	INIT_LIST_HEAD(&iter->journal.list);
 	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);
+	}
 }
 
 /*
@@ -435,21 +640,10 @@ void bch2_btree_and_journal_iter_init_node_iter(struct btree_trans *trans,
 
 	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);
-	list_add(&iter->journal.list, &trans->c->journal_iters);
 }
 
 /* sort and dedup all keys in the journal: */
 
-void bch2_journal_entries_free(struct bch_fs *c)
-{
-	struct journal_replay **i;
-	struct genradix_iter iter;
-
-	genradix_for_each(&c->journal_entries, iter, i)
-		kvfree(*i);
-	genradix_free(&c->journal_entries);
-}
-
 /*
  * When keys compare equal, oldest compares first:
  */
@@ -457,10 +651,11 @@ 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);
+		((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)
@@ -474,25 +669,45 @@ void bch2_journal_keys_put(struct bch_fs *c)
 
 	move_gap(keys, keys->nr);
 
-	darray_for_each(*keys, i)
+	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;
 
-	bch2_journal_entries_free(c);
+	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(keys->data, keys->nr, sizeof(keys->data[0]), journal_sort_key_cmp, NULL);
+	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) {
-		if (src + 1 < &darray_top(*keys) &&
+		/*
+		 * 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;
 
@@ -509,6 +724,8 @@ int bch2_journal_keys_sort(struct bch_fs *c)
 	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;
 
@@ -517,28 +734,43 @@ int bch2_journal_keys_sort(struct bch_fs *c)
 
 		cond_resched();
 
-		for_each_jset_key(k, entry, &i->j) {
-			struct journal_key n = (struct journal_key) {
-				.btree_id	= entry->btree_id,
-				.level		= entry->level,
-				.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_ENOMEM_journal_keys_sort;
+		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));
 				}
 
-				BUG_ON(darray_push(keys, n));
+				nr_read++;
 			}
-
-			nr_read++;
 		}
 	}
 
@@ -548,3 +780,51 @@ int bch2_journal_keys_sort(struct bch_fs *c)
 	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);
+}