Re: [PATCH 0/7] Convert SMMU to domain_alloc_paging()

[Jason Gunthorpe <jgg@nvidia.com>]

On Thu, Oct 05, 2023 at 03:28:11PM -0300, Jason Gunthorpe wrote:
> Add the global statics for IDENTITY and BLOCKED to the SMMU driver and
> change to use domain_alloc_paging(). This allows SMMU to finalize the
> domain during allocation.
> 
> This is a bit more urgent as I noticed while looking at Nicolin's patches
> that the disable_bypass module parameter no longer works. The system will
> boot fine but the domains will be set to IDENTITY now. To fix this the
> core code must request BLOCKED domains when using ARM DMA ops with this
> module option set.
> 
> This series fixes SMMU, which seems like the more important one of the
> two. SMMUv3 needs a similar repair, but it is more complex to get the two
> global static domains into the SMMUv3 driver. As SMMUv3 is primarily an
> ARM64 driver this is less important since the normal DMA API flow already
> substantially establishes blocking domains via empty IOMMU_DOMAIN_DMA
> attachments. Regardless I have addressed SMMUv3 seperately.
> 
> This relies on the first few patches of the dart conversion series:
> 
> https://lore.kernel.org/r/0-v2-bff223cf6409+282-dart_paging_jgg@nvidia.com
> 
> To enable the BLOCKED global static.
> 
> Jason Gunthorpe (7):
>   iommu/arm-smmu: Reorganize arm_smmu_domain_add_master()
>   iommu/arm-smmu: Convert to a global static identity domain
>   iommu/arm-smmu: Implement IOMMU_DOMAIN_BLOCKED
>   iommu/arm-smmu: Pass arm_smmu_domain to arm_smmu_init_domain_context()
>   iommu/arm-smmu: Convert to domain_alloc_paging()
>   iommu: Compute dev_iommu->require_direct sooner
>   iommu: Restore SMMU "disable_bypass"

This is still pending, it doesn't need rebasing on v6.7

The DART patches were merges so all the dependencies are in v6.7 now.

Jason