Re: [PATCH v1 2/2] dma-mapping-common: add DMA attribute - DMA_ATTR_IOMMU_BYPASS

Benjamin Herrenschmidt
2015-11-02T23:08:13Z

On Mon, 2015-11-02 at 22:45 +0100, Arnd Bergmann wrote:
> > Then I would argue for naming this differently. Make it an optional
> > hint "DMA_ATTR_HIGH_PERF" or something like that. Whether this is
> > achieved via using a bypass or other means in the backend not the
> > business of the driver.
> >
>
> With a name like that, who wouldn't pass that flag? ;-)

xHCI for example, vs. something like 10G ethernet... but yes I agree it
sucks. I don't like that sort of policy anywhere in drivers. On the
other hand the platform doesn't have much information to make that sort
of decision either.

Cheers,
Ben.