Re: [PATCH v4 05/13] iommu/arm-smmu-v3: Use the master-owned s1_cfg

[Nicolin Chen]

On Wed, Jun 21, 2023 at 02:37:17PM +0800, Michael Shavit wrote:
 
> Insert CDs for STAGE_1 domains into a CD table owned by the
> arm_smmu_master. Remove the CD table that was owned by arm_smmu_domain.

> @@ -718,10 +718,7 @@ struct arm_smmu_domain {
> 
>         enum arm_smmu_domain_stage              stage;
>         union {
> -               struct {
>                 struct arm_smmu_ctx_desc        cd;
> -               struct arm_smmu_s1_cfg          s1_cfg;
> -               };
>                 struct arm_smmu_s2_cfg          s2_cfg;
>         };

So the arm_smmu_domain looks like an object representing either:
1) a CD table + (if !IDENTITY) an S1 IOPT for default substream
2) an S2 IOPT

I wonder if we need something like struct arm_smmu_subdomain to
represent a substream, because now an IOMMU_DOMAIN_SVA domain is
represented by this struct arm_smmu_domain too, which is neither
of the two cases in the list above.

Thanks
Nicolin