Re: [RFC PATCH v2 0/7] xfs: reflink & dedupe for fsdax (read/write path).

[Shiyang Ruan <ruansy.fnst@cn.fujitsu.com>]

Hi Darrick, Dave,

Do you have any comment on this?

On 10/30/19 12:13 PM, Shiyang Ruan wrote:
> This patchset aims to take care of this issue to make reflink and dedupe
> work correctly (actually in read/write path, there still has some problems,
> such as the page->mapping and page->index issue, in mmap path) in XFS under
> fsdax mode.
> 
> It is based on Goldwyn's patchsets: "v4 Btrfs dax support" and the latest
> iomap.  I borrowed some patches related and made a few fix to make it
> basically works fine.
> 
> For dax framework:
>    1. adapt to the latest change in iomap (two iomaps).
> 
> For XFS:
>    1. distinguish dax write/zero from normal write/zero.
>    2. remap extents after COW.
>    3. add file contents comparison function based on dax framework.
>    4. use xfs_break_layouts() instead of break_layout to support dax.
> 
> 
> Goldwyn Rodrigues (3):
>    dax: replace mmap entry in case of CoW
>    fs: dedup file range to use a compare function
>    dax: memcpy before zeroing range
> 
> Shiyang Ruan (4):
>    dax: Introduce dax_copy_edges() for COW.
>    dax: copy data before write.
>    xfs: handle copy-on-write in fsdax write() path.
>    xfs: support dedupe for fsdax.
> 
>   fs/btrfs/ioctl.c       |   3 +-
>   fs/dax.c               | 211 +++++++++++++++++++++++++++++++++++++----
>   fs/iomap/buffered-io.c |   8 +-
>   fs/ocfs2/file.c        |   2 +-
>   fs/read_write.c        |  11 ++-
>   fs/xfs/xfs_bmap_util.c |   6 +-
>   fs/xfs/xfs_file.c      |  10 +-
>   fs/xfs/xfs_iomap.c     |   3 +-
>   fs/xfs/xfs_iops.c      |  11 ++-
>   fs/xfs/xfs_reflink.c   |  79 ++++++++-------
>   include/linux/dax.h    |  16 ++--
>   include/linux/fs.h     |   9 +-
>   12 files changed, 291 insertions(+), 78 deletions(-)
> 

-- 
Thanks,
Shiyang Ruan.