Do we need an opt-in for file systems use of hw atomic writes?

[Christoph Hellwig]

On Mon, Jul 14, 2025 at 11:22:43PM -0400, Martin K. Petersen wrote:
> For PCIe transport devices maybe we could consider adding an additional
> heuristic based on something like PLP or VWC?

What would you check there?  Atomic writes work perfectly fine if not
better with volatile write caches.