Hi, Currently, ext4 caches holes and initialized extents in ext4_ext_map_blocks() while it does not cache uninitialized extents. I noticed ext4 can cache uninitialized extents with minor changes. ec_start is 0 means that the cached extent is a hole, initialized extents' length is limited. So if ec_start is not 0 and the cached extent's length is larger than EXT_MAX_LENGTH, then the cached extent is uninitialized. This patch series tries to let ext4 cache uninitialized extents with minor changes. The patches pass xfstests 1-268. The xfstessts 268 and 272 meet a bug in ext4 related to changing journal mode in flight. I will fix the bug in later patches. Any feedbacks and comments are welcome. Yongqiang. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
