search for: ext4_ext_insert_extent

...will be quite a lot of uninitialized extent to be initialized during the test. After go through the src code. Call routinue is ext4_da_sritepages->mpage_da_map_blocks->ext4_get_blocks->ext4_ext_get_blocks-> ext4_ext_handle_uninitialized_extents->ext4_ext_convert_to_initialized->ext4_ext_insert_extent if ext4_ext_handle_uninitialized_extents is called, then line 3306 must be satisfied. that is we have in_range(iblock, ee_block, ee_len) = true. so iblock >= ee_block fs/ext4/extents.c 3306 <+++<+++if (in_range(iblock, ee_block, ee_len)) {...