powerpc/iommu: Support "hybrid" iommu/direct DMA ops for coherent_mask < dma_mask

[Benjamin Herrenschmidt]

On Fri, 2015-06-19 at 16:19 -0500, Brian King wrote:
> On 05/18/2015 01:40 AM, Michael Ellerman wrote:
> > On Mon, 2015-18-05 at 03:56:51 UTC, Benjamin Herrenschmidt wrote:
> >> This patch adds the ability to the DMA direct ops to fallback to the IOMMU
> >> ops for coherent alloc/free if the coherent mask of the device isn't
> >> suitable for accessing the direct DMA space and the device also happens
> >> to have an active IOMMU table.
> > 
> > Can you do the removal of the union, the #ifdef PPC64 and the static inlines as
> > a precursor patch, that would remove some of the noise in the diff.
> > 
> > And can you explain the changes to dart, pseries and powernv.
> > 
> > There's also some whitespace changes in iommu.h that I assume you didn't want?
> 
> Hi Ben,
> 
> Do you plan to resubmit with these changes? The patch seems to work fine in
> my testing. Would be nice to get this merged.

Argh, completely forgot about it. I'll respin it next week.

> Thanks,
> 
> Brian
>