Re: [RFC 2/7] iommu/vt-d: Remove iova handling code from non-dma ops path

[Lu Baolu]

Hi,

On 5/4/19 9:23 PM, Tom Murphy via iommu wrote:
> @@ -4181,58 +4168,37 @@ static int intel_iommu_memory_notifier(struct notifier_block *nb,
>   				       unsigned long val, void *v)
>   {
>   	struct memory_notify *mhp = v;
> -	unsigned long long start, end;
> -	unsigned long start_vpfn, last_vpfn;
> +	unsigned long start_vpfn = mm_to_dma_pfn(mhp->start_pfn);
> +	unsigned long last_vpfn = mm_to_dma_pfn(mhp->start_pfn +
> +			mhp->nr_pages - 1);
>   
>   	switch (val) {
>   	case MEM_GOING_ONLINE:
> -		start = mhp->start_pfn << PAGE_SHIFT;
> -		end = ((mhp->start_pfn + mhp->nr_pages) << PAGE_SHIFT) - 1;
> -		if (iommu_domain_identity_map(si_domain, start, end)) {
> -			pr_warn("Failed to build identity map for [%llx-%llx]\n",
> -				start, end);
> +		if (iommu_domain_identity_map(si_domain, start_vpfn,
> +					last_vpfn)) {
> +			pr_warn("Failed to build identity map for [%lx-%lx]\n",
> +				start_vpfn, last_vpfn);
>   			return NOTIFY_BAD;
>   		}
>   		break;

Actually we don't need to update the si_domain if iommu hardware
supports pass-through mode. This should be made in a separated patch
anyway.

Best regards,
Lu Baolu