Re: [PATCH v3 06/13] xen/passthrough: iommu: Split generic IOMMU code

[Julien Grall <julien.grall@linaro.org>]

Hello Jan,

On 03/11/2014 04:50 PM, Jan Beulich wrote:
>>>> On 11.03.14 at 16:49, Julien Grall <julien.grall@linaro.org> wrote:
>> --- a/xen/drivers/passthrough/pci.c
>> +++ b/xen/drivers/passthrough/pci.c
>> ...
>> +static int iommu_populate_page_table(struct domain *d)
>> +{
> 
> I continue to be of the opinion that this is misplaced here. There's
> nothing PCI-related in this function, and I doubt you can get away
> on ARM without similar code (if you can, this should go into
> .../x86/iommu.c imo).

On ARM, the page table is shared with the processor, we don't need to
populate the page table. Furthermore, this function is using
"arch.relmem_list", which is not implemented on ARM.

I can move it in x86/iommu.c and implemented the function is no-op on ARM.

> 
>> --- /dev/null
>> +++ b/xen/include/asm-x86/iommu.h
>> ...
>> +void iommu_set_dom0_mapping(struct domain *d);
> 
> How is this x86-specific?

iommu_set_dom0_mapping is implemented in vtd/x86/vtd.c and only used by
vtd/iommu.c.

I think this function should be renamed to iommu_vtd_set_dom0_mapping.

Regards,

-- 
Julien Grall