ASSERT (bitmap_all (pool->used_map, page_idx, page_idx + page_cnt));
bitmap_set_multiple (pool->used_map, page_idx, page_idx + page_cnt, false);
ASSERT (bitmap_all (pool->used_map, page_idx, page_idx + page_cnt));
bitmap_set_multiple (pool->used_map, page_idx, page_idx + page_cnt, false);