Re: [PATCH v1 2/2] dma: Add IOMMU static calls with clear default ops

Leon Romanovsky
2024-07-17T09:53:35Z

On Wed, Jul 17, 2024 at 10:56:52AM +0200, Christoph Hellwig wrote:
> On Wed, Jul 17, 2024 at 11:47:13AM +0300, Leon Romanovsky wrote:
> > It will cause to the situation where "struct device" memory footprint
> > will increase, while we still need to keep dma_ops for archs that don't
> > want to use default IOMMU.
>
> It won't. Even with the new bit we still have 28 more spare bits next
> to it :)
>
> > Because dma_ops pointer exists anyway and has already specific flags. I
> > decided to take evolutive approach and add a new flag to it, instead of
> > revolutionary approach and add a new field to struct device.
>
> The point is that with a little more work we can actually kill that
> for common configuration. For non-Xen setups that basically just means
> removing the dummy ops, so it's a pretty big quick win.

No problem, I'll do it.

Thanks