+static int check_overlapping_extents(struct btree_trans *trans,
+ struct snapshots_seen *seen,
+ extent_ends *extent_ends,
+ struct bkey_s_c k,
+ struct btree_iter *iter)
+{
+ struct bch_fs *c = trans->c;
+ struct extent_end *i;
+ struct printbuf buf = PRINTBUF;
+ int ret = 0;
+
+ darray_for_each(*extent_ends, i) {
+ /* duplicate, due to transaction restart: */
+ if (i->offset == k.k->p.offset &&
+ i->snapshot == k.k->p.snapshot)
+ continue;
+
+ if (!ref_visible2(c,
+ k.k->p.snapshot, seen,
+ i->snapshot, &i->seen))
+ continue;
+
+ if (i->offset <= bkey_start_offset(k.k))
+ continue;
+
+ printbuf_reset(&buf);
+ prt_str(&buf, "overlapping extents:\n ");
+ bch2_bkey_val_to_text(&buf, c, k);
+ prt_str(&buf, "\n ");
+
+ ret = get_print_extent(trans, SPOS(k.k->p.inode, i->offset, i->snapshot), &buf);
+ if (ret)
+ break;
+
+ if (fsck_err(c, "%s", buf.buf)) {
+ struct bkey_i *update = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
+ if ((ret = PTR_ERR_OR_ZERO(update)))
+ goto err;
+ bkey_reassemble(update, k);
+ ret = bch2_trans_update_extent(trans, iter, update,
+ BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE);
+ if (ret)
+ goto err;
+ }
+ }
+err:
+fsck_err:
+ printbuf_exit(&buf);
+ return ret;
+}
+
+static int extent_ends_at(extent_ends *extent_ends,
+ struct snapshots_seen *seen,
+ struct bkey_s_c k)
+{
+ struct extent_end *i, n = (struct extent_end) {
+ .snapshot = k.k->p.snapshot,
+ .offset = k.k->p.offset,
+ .seen = *seen,
+ };
+
+ n.seen.ids.data = kmemdup(seen->ids.data,
+ sizeof(seen->ids.data[0]) * seen->ids.size,
+ GFP_KERNEL);
+ if (!n.seen.ids.data)
+ return -BCH_ERR_ENOMEM_fsck_extent_ends_at;
+
+ darray_for_each(*extent_ends, i) {
+ if (i->snapshot == k.k->p.snapshot) {
+ snapshots_seen_exit(&i->seen);
+ *i = n;
+ return 0;
+ }
+
+ if (i->snapshot >= k.k->p.snapshot)
+ break;
+ }
+
+ return darray_insert_item(extent_ends, i - extent_ends->data, n);
+}
+
+static void extent_ends_reset(extent_ends *extent_ends)
+{
+ struct extent_end *i;
+
+ darray_for_each(*extent_ends, i)
+ snapshots_seen_exit(&i->seen);
+
+ extent_ends->nr = 0;
+}
+
+static int check_extent(struct btree_trans *trans, struct btree_iter *iter,
+ struct bkey_s_c k,
+ struct inode_walker *inode,
+ struct snapshots_seen *s,
+ extent_ends *extent_ends)
+{
+ struct bch_fs *c = trans->c;
+ struct inode_walker_entry *i;
+ struct printbuf buf = PRINTBUF;
+ struct bpos equiv;
+ int ret = 0;
+
+ ret = check_key_has_snapshot(trans, iter, k);
+ if (ret) {
+ ret = ret < 0 ? ret : 0;
+ goto out;
+ }
+
+ equiv = k.k->p;
+ equiv.snapshot = bch2_snapshot_equiv(c, k.k->p.snapshot);
+
+ ret = snapshots_seen_update(c, s, iter->btree_id, k.k->p);
+ if (ret)
+ goto err;