Re: [PATCH v6 05/07] iommu/ipmmu-vmsa: Add new IOMMU_DOMAIN_DMA ops

Laurent Pinchart
2016-11-11T01:13:32Z

Hello,

On Thursday 10 Nov 2016 12:42:06 Joerg Roedel wrote:
> On Fri, Oct 21, 2016 at 06:52:53PM +0100, Robin Murphy wrote:
> > > -static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
> > > -{
> > > - if (type != IOMMU_DOMAIN_UNMANAGED)
> > > - return NULL;
> >
> > I *think* that if we did the initial check thus:
> > if (type != IOMMU_DOMAIN_UNMANAGED ||
> >
> > (IS_ENABLED(CONFIG_IOMMU_DMA) && type != IOMMU_DOMAIN_DMA))
> >
> > return NULL;
> >
> > it shouldn't be necessary to split the function at all - we then just
> > wrap the {get,put}_cookie() bits in "if (type == IOMMU_DOMAIN_DMA)" and
> > in the 32-bit ARM case they just don't run as that can never be true.
>
> This would be a good improvement. Magnus, Robin, can either of you send
> a follow-on patch to implement this suggestion? I have applied these
> patches to my arm/renesas branch (not pushed yet). The patch can be
> based on it.

I like the suggestion too, a patch is on its way.

Joerg, as I've sent a few comments about the other patches (sorry for the late
review, I got delayed by KS and LPC), the follow-up patch should probably be
squashed into this one when Magnus addresses my comments. Could you please
hold off pushing the arm/renesas branch until Magnus replies to this ?

--
Regards,

Laurent Pinchart