[PATCH v7 13/14] iommu/arm-smmu-v3: Allow a PASID to be set when RID is IDENTITY/BLOCKED

[Nicolin Chen]

On Wed, May 08, 2024 at 03:57:21PM -0300, Jason Gunthorpe wrote:
> If the STE doesn't point to the CD table we can upgrade it by
> reprogramming the STE with the appropriate S1DSS. We may also need to turn
> on ATS at the same time.
> 
> Keep track if the installed STE is pointing at the cd_table and the ATS
> state to trigger this path.
> 
> Tested-by: Nicolin Chen <nicolinc at nvidia.com>
> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi at huawei.com>
> Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
> ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 49 ++++++++++++++++++++-
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h |  3 +-
>  2 files changed, 49 insertions(+), 3 deletions(-)
  
> @@ -2819,6 +2851,19 @@ static void arm_smmu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
>  		arm_smmu_atc_inv_master(master, pasid);
>  	arm_smmu_remove_master_domain(master, &smmu_domain->domain, pasid);
>  	mutex_unlock(&arm_smmu_asid_lock);
> +
> +	/*
> +	 * When the last user of the CD table goes away downgrade the STE back
> +	 * to a non-cd_table one.
> +	 */
> +	if (!arm_smmu_ssids_in_use(&master->cd_table)) {
> +		struct iommu_domain *sid_domain =
> +			iommu_get_domain_for_dev(master->dev);
> +
> +		if (domain->type == IOMMU_DOMAIN_IDENTITY ||
> +		    domain->type == IOMMU_DOMAIN_BLOCKED)
> +			sid_domain->ops->attach_dev(sid_domain, dev);

Should we check against sid_domain->type instead?

Thanks
Nicolin