+struct bch_fs_usage_short
+bch2_fs_usage_read_short(struct bch_fs *);
+
+/* key/bucket marking: */
+
+void bch2_fs_usage_initialize(struct bch_fs *);
+
+int bch2_mark_metadata_bucket(struct bch_fs *, struct bch_dev *,
+ size_t, enum bch_data_type, unsigned,
+ struct gc_pos, unsigned);
+
+int bch2_mark_alloc(struct btree_trans *, enum btree_id, unsigned,
+ struct bkey_s_c, struct bkey_s_c, unsigned);
+int bch2_mark_extent(struct btree_trans *, enum btree_id, unsigned,
+ struct bkey_s_c, struct bkey_s_c, unsigned);
+int bch2_mark_stripe(struct btree_trans *, enum btree_id, unsigned,
+ struct bkey_s_c, struct bkey_s_c, unsigned);
+int bch2_mark_inode(struct btree_trans *, enum btree_id, unsigned,
+ struct bkey_s_c, struct bkey_s_c, unsigned);
+int bch2_mark_reservation(struct btree_trans *, enum btree_id, unsigned,
+ struct bkey_s_c, struct bkey_s_c, unsigned);
+int bch2_mark_reflink_p(struct btree_trans *, enum btree_id, unsigned,
+ struct bkey_s_c, struct bkey_s_c, unsigned);
+
+int bch2_trans_mark_extent(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
+int bch2_trans_mark_stripe(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
+int bch2_trans_mark_inode(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
+int bch2_trans_mark_reservation(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
+int bch2_trans_mark_reflink_p(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
+
+void bch2_trans_fs_usage_revert(struct btree_trans *, struct replicas_delta_list *);
+int bch2_trans_fs_usage_apply(struct btree_trans *, struct replicas_delta_list *);
+
+int bch2_trans_mark_metadata_bucket(struct btree_trans *, struct bch_dev *,
+ size_t, enum bch_data_type, unsigned);
+int bch2_trans_mark_dev_sb(struct bch_fs *, struct bch_dev *);
+
+/* disk reservations: */