[RFC PATCH v2 9/9] iommu/arm-smmu-v3: allow multi-SMMU domain installs.

[Michael Shavit]

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>
---

(no changes since v1)

 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 10 +++-------
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h |  3 +--
 2 files changed, 4 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 9f8b701771fc3..55c0b8aecfb0a 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2564,13 +2564,9 @@ 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 ||
-		   !arm_smmu_verify_domain_compatible(smmu, smmu_domain))
+	if (!smmu_domain->pgtbl_ops)
+		ret = arm_smmu_domain_finalise(&smmu_domain->domain, smmu);
+	else if (!arm_smmu_verify_domain_compatible(smmu, smmu_domain))
 		ret = -EINVAL;
 
 	mutex_unlock(&smmu_domain->init_mutex);
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 1661d3252bac5..fcf3845f4659c 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -716,8 +716,7 @@ 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;
 	atomic_t			nr_ats_masters;
-- 
2.42.0.rc1.204.g551eb34607-goog