[PATCH v2 01/11] iommu/arm-smmu-v3: Pass in vmid to arm_smmu_make_s2_domain_ste()

[Nicolin Chen <nicolinc@nvidia.com>]

An stage-2 STE requires a vmid that has been so far allocated per domain,
so arm_smmu_make_s2_domain_ste() has been extracting the vmid from the S2
domain.

To share an S2 parent domain across vSMMUs in the same VM, a vmid will be
no longer allocated for nor stored in the S2 domain, but per vSMMU, which
means the arm_smmu_make_s2_domain_ste() can get a vmid either from an S2
domain (non nesting parent) or a vSMMU.

Allow to pass in vmid explicitly to arm_smmu_make_s2_domain_ste(), giving
its callers a chance to pick the vmid between a domain or a vSMMU. Add a
WARN_ON_ONCE to validate the input vmid.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h         | 2 +-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c | 6 ++++--
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c    | 3 ++-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c         | 8 +++++---
 4 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index dd1ad56ce863..d4837a33fb81 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -894,7 +894,7 @@ struct arm_smmu_entry_writer_ops {
 void arm_smmu_make_abort_ste(struct arm_smmu_ste *target);
 void arm_smmu_make_s2_domain_ste(struct arm_smmu_ste *target,
 				 struct arm_smmu_master *master,
-				 struct arm_smmu_domain *smmu_domain,
+				 struct arm_smmu_domain *smmu_domain, u16 vmid,
 				 bool ats_enabled);
 
 #if IS_ENABLED(CONFIG_KUNIT)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
index e4fd8d522af8..d86dba6691e8 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
@@ -34,8 +34,9 @@ static void arm_smmu_make_nested_cd_table_ste(
 	struct arm_smmu_ste *target, struct arm_smmu_master *master,
 	struct arm_smmu_nested_domain *nested_domain, bool ats_enabled)
 {
-	arm_smmu_make_s2_domain_ste(
-		target, master, nested_domain->vsmmu->s2_parent, ats_enabled);
+	arm_smmu_make_s2_domain_ste(target, master,
+				    nested_domain->vsmmu->s2_parent,
+				    nested_domain->vsmmu->vmid, ats_enabled);
 
 	target->data[0] = cpu_to_le64(STRTAB_STE_0_V |
 				      FIELD_PREP(STRTAB_STE_0_CFG,
@@ -78,6 +79,7 @@ static void arm_smmu_make_nested_domain_ste(
 	case STRTAB_STE_0_CFG_BYPASS:
 		arm_smmu_make_s2_domain_ste(target, master,
 					    nested_domain->vsmmu->s2_parent,
+					    nested_domain->vsmmu->vmid,
 					    ats_enabled);
 		break;
 	case STRTAB_STE_0_CFG_ABORT:
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c
index d2671bfd3798..7fac5a112c5c 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c
@@ -316,7 +316,8 @@ static void arm_smmu_test_make_s2_ste(struct arm_smmu_ste *ste,
 	io_pgtable.cfg.arm_lpae_s2_cfg.vtcr.sl = 3;
 	io_pgtable.cfg.arm_lpae_s2_cfg.vtcr.tsz = 4;
 
-	arm_smmu_make_s2_domain_ste(ste, &master, &smmu_domain, ats_enabled);
+	arm_smmu_make_s2_domain_ste(ste, &master, &smmu_domain,
+				    smmu_domain.s2_cfg.vmid, ats_enabled);
 }
 
 static void arm_smmu_v3_write_ste_test_s2_to_abort(struct kunit *test)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index c32c0b92dc69..1ec5efca1d42 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1656,10 +1656,9 @@ EXPORT_SYMBOL_IF_KUNIT(arm_smmu_make_cdtable_ste);
 
 void arm_smmu_make_s2_domain_ste(struct arm_smmu_ste *target,
 				 struct arm_smmu_master *master,
-				 struct arm_smmu_domain *smmu_domain,
+				 struct arm_smmu_domain *smmu_domain, u16 vmid,
 				 bool ats_enabled)
 {
-	struct arm_smmu_s2_cfg *s2_cfg = &smmu_domain->s2_cfg;
 	const struct io_pgtable_cfg *pgtbl_cfg =
 		&io_pgtable_ops_to_pgtable(smmu_domain->pgtbl_ops)->cfg;
 	typeof(&pgtbl_cfg->arm_lpae_s2_cfg.vtcr) vtcr =
@@ -1667,6 +1666,8 @@ void arm_smmu_make_s2_domain_ste(struct arm_smmu_ste *target,
 	u64 vtcr_val;
 	struct arm_smmu_device *smmu = master->smmu;
 
+	WARN_ON_ONCE(!vmid);
+
 	memset(target, 0, sizeof(*target));
 	target->data[0] = cpu_to_le64(
 		STRTAB_STE_0_V |
@@ -1690,7 +1691,7 @@ void arm_smmu_make_s2_domain_ste(struct arm_smmu_ste *target,
 		   FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, vtcr->tg) |
 		   FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, vtcr->ps);
 	target->data[2] = cpu_to_le64(
-		FIELD_PREP(STRTAB_STE_2_S2VMID, s2_cfg->vmid) |
+		FIELD_PREP(STRTAB_STE_2_S2VMID, vmid) |
 		FIELD_PREP(STRTAB_STE_2_VTCR, vtcr_val) |
 		STRTAB_STE_2_S2AA64 |
 #ifdef __BIG_ENDIAN
@@ -2990,6 +2991,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 	}
 	case ARM_SMMU_DOMAIN_S2:
 		arm_smmu_make_s2_domain_ste(&target, master, smmu_domain,
+					    smmu_domain->s2_cfg.vmid,
 					    state.ats_enabled);
 		arm_smmu_install_ste_for_dev(master, &target);
 		arm_smmu_clear_cd(master, IOMMU_NO_PASID);
-- 
2.43.0