[PATCH v8 05/10] block: Add core atomic write support

[Christoph Hellwig]

On Wed, Jun 19, 2024 at 08:59:33AM +0100, John Garry wrote:
> In this case, I would expect NOIOB >= atomic write boundary.
>
> Would it be sane to have a NOIOB < atomic write boundary in some other 
> config?
>
> I can support these possibilities, but the code will just get more complex.

I'd be tempted to simply not support the case where NOIOB is not a
multiple of the atomic write boundary for now and disable atomic writes
with a big fat warning (and a good comment in the soure code).  If users
show up with a device that hits this and want to use atomic writes we
can resolved it.