bcachefs: btree_and_journal_iter.trans

we now always have a btree_trans when using a btree_and_journal_iter;
prep work for adding prefetching to btree_and_journal_iter
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_gc.c

@@ -389,7 +389,7 @@ static int bch2_btree_repair_topology_recurse(struct btree_trans *trans, struct
 	have_child = dropped_children = false;
 	bch2_bkey_buf_init(&prev_k);
 	bch2_bkey_buf_init(&cur_k);
-	bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
+	bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
 
 	while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
 		BUG_ON(bpos_lt(k.k->p, b->data->min_key));
@@ -478,7 +478,7 @@ static int bch2_btree_repair_topology_recurse(struct btree_trans *trans, struct
 		goto err;
 
 	bch2_btree_and_journal_iter_exit(&iter);
-	bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
+	bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
 
 	while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
 		bch2_bkey_buf_reassemble(&cur_k, c, k);
@@ -931,7 +931,7 @@ static int bch2_gc_btree_init_recurse(struct btree_trans *trans, struct btree *b
 	struct printbuf buf = PRINTBUF;
 	int ret = 0;
 
-	bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
+	bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
 	bch2_bkey_buf_init(&prev);
 	bch2_bkey_buf_init(&cur);
 	bkey_init(&prev.k->k);
@@ -963,7 +963,7 @@ static int bch2_gc_btree_init_recurse(struct btree_trans *trans, struct btree *b
 
 	if (b->c.level > target_depth) {
 		bch2_btree_and_journal_iter_exit(&iter);
-		bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
+		bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
 
 		while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
 			struct btree *child;

fs/bcachefs/btree_iter.c

@@ -891,7 +891,7 @@ static noinline int btree_node_iter_and_journal_peek(struct btree_trans *trans,
 	struct bkey_s_c k;
 	int ret = 0;
 
-	__bch2_btree_and_journal_iter_init_node_iter(&jiter, c, l->b, l->iter, path->pos);
+	__bch2_btree_and_journal_iter_init_node_iter(trans, &jiter, l->b, l->iter, path->pos);
 
 	k = bch2_btree_and_journal_iter_peek(&jiter);
 

fs/bcachefs/btree_journal_iter.c

@@ -376,17 +376,18 @@ 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_and_journal_iter *iter,
-						  struct bch_fs *c,
+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;
-	bch2_journal_iter_init(c, &iter->journal, b->c.btree_id, b->c.level, pos);
+	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;
@@ -396,15 +397,15 @@ void __bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter
  * 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_and_journal_iter *iter,
-						struct bch_fs *c,
+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(iter, c, b, node_iter, b->data->min_key);
-	list_add(&iter->journal.list, &c->journal_iters);
+	__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: */

fs/bcachefs/btree_journal_iter.h

@@ -15,6 +15,7 @@ struct journal_iter {
  */
 
 struct btree_and_journal_iter {
+	struct btree_trans	*trans;
 	struct btree		*b;
 	struct btree_node_iter	node_iter;
 	struct bkey		unpacked;
@@ -29,6 +30,9 @@ struct bkey_i *bch2_journal_keys_peek_upto(struct bch_fs *, enum btree_id,
 struct bkey_i *bch2_journal_keys_peek_slot(struct bch_fs *, enum btree_id,
 					   unsigned, struct bpos);
 
+int bch2_btree_and_journal_iter_prefetch(struct btree_trans *, struct btree_path *,
+					 struct btree_and_journal_iter *);
+
 int bch2_journal_key_insert_take(struct bch_fs *, enum btree_id,
 				 unsigned, struct bkey_i *);
 int bch2_journal_key_insert(struct bch_fs *, enum btree_id,
@@ -42,12 +46,11 @@ void bch2_btree_and_journal_iter_advance(struct btree_and_journal_iter *);
 struct bkey_s_c bch2_btree_and_journal_iter_peek(struct btree_and_journal_iter *);
 
 void bch2_btree_and_journal_iter_exit(struct btree_and_journal_iter *);
-void __bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter *,
-				struct bch_fs *, struct btree *,
+void __bch2_btree_and_journal_iter_init_node_iter(struct btree_trans *,
+				struct btree_and_journal_iter *, struct btree *,
 				struct btree_node_iter, struct bpos);
-void bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter *,
-						struct bch_fs *,
-						struct btree *);
+void bch2_btree_and_journal_iter_init_node_iter(struct btree_trans *,
+				struct btree_and_journal_iter *, struct btree *);
 
 void bch2_journal_keys_put(struct bch_fs *);