Hi folks, This patchset mainly adds preliminary EROFS iomap dio/dax support for non-tailpacking uncompressed cases. Direct I/O is useful in certain scenarios for uncompressed files. For example, double pagecache can be avoid by direct I/O when loop device is used for uncompressed files containing upper layer compressed filesystem. Also, DAX is quite useful for some VM use cases in order to save guest memory extremely by using the minimal lightweight EROFS. Tail-packing inline iomap support will be handled later since currently iomap doesn't support such data pattern, which is independent to non-tailpacking cases. Comments are welcome. Thanks for your time on reading this! Thanks, Gao Xiang changes since v1: - allow 'dax=always' and 'dax=never' to keep in sync with ext4/xfs Gao Xiang (1): erofs: dax support for non-tailpacking regular file Huang Jianan (1): erofs: iomap support for non-tailpacking DIO fs/erofs/Kconfig | 1 + fs/erofs/data.c | 142 +++++++++++++++++++++++++++++++++++++++++++- fs/erofs/inode.c | 9 ++- fs/erofs/internal.h | 4 ++ fs/erofs/super.c | 60 ++++++++++++++++++- 5 files changed, 212 insertions(+), 4 deletions(-) -- 2.24.4
