Re: [PATCH v6 08/18] iommu/vt-d: Implement reserved region get/put callbacks

[Auger Eric]

Hi Joerg,

On 06/01/2017 12:01, Joerg Roedel wrote:
> On Thu, Jan 05, 2017 at 07:04:36PM +0000, Eric Auger wrote:
>> +static void intel_iommu_get_resv_regions(struct device *device,
>> +					 struct list_head *head)
>> +{
>> +	struct iommu_resv_region *reg;
>> +
>> +	reg = iommu_alloc_resv_region(IOAPIC_RANGE_START,
>> +				      IOAPIC_RANGE_END - IOAPIC_RANGE_START + 1,
>> +				      0, IOMMU_RESV_NOMAP);
>> +	if (!reg)
>> +		return;
>> +	list_add_tail(&reg->list, head);
>> +}
> 
> That is different from what AMD does, can you also report the RMRR
> regions for the device here (as direct-map regions)?

if I return RMRR regions as direct mapped regions,
iommu_group_create_direct_mappings will perform the 1-1 mapping.

I am not familiar with the intel-iommu code but I guess this job
currently is done in the intel driver:
iommu_prepare_rmrr_dev -> iommu_prepare_identity_map
->domain_prepare_identity_map -> iommu_domain_identity_map?

What is your feeling?

Thanks

Eric
> 
> 
> 
> 	Joerg
>