Commit 874b87c7 authored by Jason Gunthorpe's avatar Jason Gunthorpe Committed by Will Deacon
Browse files

iommu/arm-smmu-v3: Implement IOMMU_HWPT_ALLOC_NEST_PARENT 



For SMMUv3 the parent must be a S2 domain, which can be composed
into a IOMMU_DOMAIN_NESTED.

In future the S2 parent will also need a VMID linked to the VIOMMU and
even to KVM.

Reviewed-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Tested-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Reviewed-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: default avatarMostafa Saleh <smostafa@google.com>
Reviewed-by: default avatarDonald Dutile <ddutile@redhat.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/6-v4-9e99b76f3518+3a8-smmuv3_nesting_jgg@nvidia.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 6912ec91

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c

+10 −1
Original line number Diff line number Diff line
@@ -3114,7 +3114,8 @@ arm_smmu_domain_alloc_user(struct device *dev, u32 flags, 
			   const struct iommu_user_data *user_data)

{

	struct arm_smmu_master *master = dev_iommu_priv_get(dev);

	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING;

	const u32 PAGING_FLAGS = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |

				 IOMMU_HWPT_ALLOC_NEST_PARENT;

	struct arm_smmu_domain *smmu_domain;

	int ret;
@@ -3127,6 +3128,14 @@ arm_smmu_domain_alloc_user(struct device *dev, u32 flags, 
	if (IS_ERR(smmu_domain))

		return ERR_CAST(smmu_domain);



	if (flags & IOMMU_HWPT_ALLOC_NEST_PARENT) {

		if (!(master->smmu->features & ARM_SMMU_FEAT_NESTING)) {

			ret = -EOPNOTSUPP;

			goto err_free;

		}

		smmu_domain->stage = ARM_SMMU_DOMAIN_S2;

	}



	smmu_domain->domain.type = IOMMU_DOMAIN_UNMANAGED;

	smmu_domain->domain.ops = arm_smmu_ops.default_domain_ops;

	ret = arm_smmu_domain_finalise(smmu_domain, master->smmu, flags);