Hi folks, This patchset mainly adds EROFS iomap support for uncompressed cases I've planed for the next merge window. The first 2 patches mainly deal with 2 new cases: 1) 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. 2) DAX is quite useful for some container use cases in order to save guest memory extremely by using the minimal lightweight EROFS image. BTW, a bit more off this iomap topic, chunk-deduplicated regfile support is almost available (blob data support) for multi-layer container image use cases (aka. called RAFS v6, nydus [1] will support RAFS v6 (EROFS-compatible format) in the future and form a unified high-performance container image solution, which will be announced formally independently), which is also a small independent update. The last patch relies on the previous iomap core update in order to convert tail-packing inline files into iomap, thus all uncompressed cases are handled with iomap properly. Comments are welcome. Thanks for your time on reading this! Thanks, Gao Xiang [1] https://github.com/dragonflyoss/image-service changes since v2 (Chao): - use filemap_read() instead; - slightly adjust the order of a hunk in erofs_fill_inode(); - update brief documentation for dax option; - use fs_put_dax() directly w/o NULL check; - add a missing error handling for erofs_get_meta_page(). Gao Xiang (2): erofs: dax support for non-tailpacking regular file erofs: convert all uncompressed cases to iomap Huang Jianan (1): erofs: iomap support for non-tailpacking DIO Documentation/filesystems/erofs.rst | 2 + fs/erofs/Kconfig | 1 + fs/erofs/data.c | 338 ++++++++++++---------------- fs/erofs/inode.c | 9 +- fs/erofs/internal.h | 4 + fs/erofs/super.c | 59 ++++- 6 files changed, 213 insertions(+), 200 deletions(-) -- 2.24.4
