[RFC PATCH v1 8/8] iommu/arm-smmu-v3: allow multi-SMMU domain installs

Michael Shavit mshavit at google.com
Thu Aug 17 11:16:30 PDT 2023


Remove the arm_smmu_domain->smmu handle now that a domain may be
attached to devices with different upstream SMMUs.

Signed-off-by: Michael Shavit <mshavit at google.com>
---

 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 9 ++-------
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 3 +--
 2 files changed, 3 insertions(+), 9 deletions(-)

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 c9f89f4f47721..08594612a81a8 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2587,13 +2587,8 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 
 	mutex_lock(&smmu_domain->init_mutex);
 
-	if (!smmu_domain->smmu) {
-		smmu_domain->smmu = smmu;
-		ret = arm_smmu_domain_finalise(domain, smmu);
-		if (ret)
-			smmu_domain->smmu = NULL;
-	} else if (smmu_domain->smmu != smmu)
-		ret = -EINVAL;
+	if (!smmu_domain->pgtbl_ops)
+		ret = arm_smmu_domain_finalise(&smmu_domain->domain, smmu);
 
 	mutex_unlock(&smmu_domain->init_mutex);
 	if (ret)
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 143b287be2f8b..342fa6ef837ab 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -726,8 +726,7 @@ enum arm_smmu_domain_stage {
 };
 
 struct arm_smmu_domain {
-	struct arm_smmu_device		*smmu;
-	struct mutex			init_mutex; /* Protects smmu pointer */
+	struct mutex			init_mutex; /* Protects pgtbl_ops pointer */
 
 	struct io_pgtable_ops		*pgtbl_ops;
 	struct io_pgtable_cfg		pgtbl_cfg;
-- 
2.42.0.rc1.204.g551eb34607-goog




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