On Fri, 2022-07-22 at 00:12 -0700, Eric Biggers wrote: > This patchset makes the statx() system call return direct I/O (DIO) > alignment information. This allows userspace to easily determine > whether a file supports DIO, and if so with what alignment restrictions. > > Patch 1 adds the basic VFS support for STATX_DIOALIGN. Patch 2 wires it > up for all block device files. The remaining patches wire it up for > regular files on ext4, f2fs, and xfs. Support for regular files on > other filesystems can be added later. > > I've also written a man-pages patch, which I'm sending separately. > > Note, f2fs has one corner case where DIO reads are allowed but not DIO > writes. The proposed statx fields can't represent this. My proposal > (patch 6) is to just eliminate this case, as it seems much too weird. > But I'd appreciate any feedback on that part. > > This patchset applies to v5.19-rc7. > > Changed v3 => v4: > - Added xfs support. > > - Moved the helper function for block devices into block/bdev.c. > > - Adjusted the ext4 patch to not introduce a bug where misaligned DIO > starts being allowed on encrypted files when it gets combined with > the patch "iomap: add support for dma aligned direct-io" that is > queued in the block tree for 5.20. > > - Made a simplification in fscrypt_dio_supported(). > > Changed v2 => v3: > - Dropped the stx_offset_align_optimal field, since its purpose > wasn't clearly distinguished from the existing stx_blksize. > > - Renamed STATX_IOALIGN to STATX_DIOALIGN, to reflect the new focus > on DIO only. > > - Similarly, renamed stx_{mem,offset}_align_dio to > stx_dio_{mem,offset}_align, to reflect the new focus on DIO only. > > - Wired up STATX_DIOALIGN on block device files. > > Changed v1 => v2: > - No changes. > > Eric Biggers (9): > statx: add direct I/O alignment information > vfs: support STATX_DIOALIGN on block devices > fscrypt: change fscrypt_dio_supported() to prepare for STATX_DIOALIGN > ext4: support STATX_DIOALIGN > f2fs: move f2fs_force_buffered_io() into file.c > f2fs: don't allow DIO reads but not DIO writes > f2fs: simplify f2fs_force_buffered_io() > f2fs: support STATX_DIOALIGN > xfs: support STATX_DIOALIGN > > block/bdev.c | 25 ++++++++++++++++++++ > fs/crypto/inline_crypt.c | 49 +++++++++++++++++++-------------------- > fs/ext4/ext4.h | 1 + > fs/ext4/file.c | 37 ++++++++++++++++++++--------- > fs/ext4/inode.c | 36 ++++++++++++++++++++++++++++ > fs/f2fs/f2fs.h | 45 ----------------------------------- > fs/f2fs/file.c | 45 ++++++++++++++++++++++++++++++++++- > fs/stat.c | 14 +++++++++++ > fs/xfs/xfs_iops.c | 9 +++++++ > include/linux/blkdev.h | 4 ++++ > include/linux/fscrypt.h | 7 ++---- > include/linux/stat.h | 2 ++ > include/uapi/linux/stat.h | 4 +++- > 13 files changed, 190 insertions(+), 88 deletions(-) > > base-commit: ff6992735ade75aae3e35d16b17da1008d753d28 Hi Eric, Can I ask what your plans are with this set? I didn't see it in linux-next yet, so I wasn't sure when you were looking to get it merged. I'm working on patches to add a new statx field for the i_version counter as well and I want to make sure that our work doesn't collide. Thanks, -- Jeff Layton <jlayton@xxxxxxxxxx>
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