Re: [PATCH v5 7/7] ext4: Add atomic block write documentation

[Ritesh Harjani (IBM) <ritesh.list@gmail.com>]

"Theodore Ts'o" <tytso@mit.edu> writes:

> On Fri, May 16, 2025 at 09:55:09AM +0100, John Garry wrote:
>> 
>> Or move this file to a common location, and have separate sections for ext4
>> and xfs? This would save having scattered files for instructions.
>
> What is the current outook for the xfs changes landing in the next
> merge window?  I haven't been tracking the latest rounds of reviews
> for the xfs atomic writes patchset.
>
> If the xfs atomic writes patchset aren't going to land this window,
> then we can land them as ext4 specific documentation, and when the xfs
> patches land, we can reorganize the documentation at that point.  Does
> that make sense?
>

IMO, the current documentation is primarily intended to capture notes
from ext4's implementation perspective of single and multi-fsblock
atomic writes.

I guess adding a more general atomic write documentation require a lot
of other grounds to cover too e.g. 
- block device driver support (scsi & nvme, dm-... )
- block layer support (bio split & merge )
- Filesystem & iomap support (iomap, ext4, xfs)
- VFS layer support (statx, pwritev2...)

So, IMO, even with XFS atomic writes patches queued for v6.16, the
current documentation still stands correct. To cover more ground around
atomic writes detail, we can think of adding a common documentation
later which can refer to individual filesystem's documentation file for
implementation notes.

Thoughts?

-ritesh