[PATCH v2 14/19] iommu/arm-smmu-v3: Remove arm_smmu_master->domain

[Jason Gunthorpe]

Introducing global statics which are of type struct iommu_domain, not
struct arm_smmu_domain makes it difficult to retain
arm_smmu_master->domain, as it can no longer point to an IDENTITY or
BLOCKED domain.

The only place that uses the value is arm_smmu_detach_dev(). Change things
to work like other drivers and call iommu_get_domain_for_dev() to obtain
the current domain.

Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 21 +++++++--------------
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h |  1 -
 2 files changed, 7 insertions(+), 15 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 7d2dd3ea47ab68..23dda64722ea17 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2480,19 +2480,20 @@ static void arm_smmu_disable_pasid(struct arm_smmu_master *master)
 
 static void arm_smmu_detach_dev(struct arm_smmu_master *master)
 {
+	struct iommu_domain *domain = iommu_get_domain_for_dev(master->dev);
+	struct arm_smmu_domain *smmu_domain;
 	unsigned long flags;
-	struct arm_smmu_domain *smmu_domain = master->domain;
 
-	if (!smmu_domain)
+	if (!domain)
 		return;
 
+	smmu_domain = to_smmu_domain(domain);
 	arm_smmu_disable_ats(master, smmu_domain);
 
 	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
 	list_del(&master->domain_head);
 	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
 
-	master->domain = NULL;
 	master->ats_enabled = false;
 }
 
@@ -2546,8 +2547,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 
 	arm_smmu_detach_dev(master);
 
-	master->domain = smmu_domain;
-
 	/*
 	 * The SMMU does not support enabling ATS with bypass. When the STE is
 	 * in bypass (STE.Config[2:0] == 0b100), ATS Translation Requests and
@@ -2566,10 +2565,8 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 	case ARM_SMMU_DOMAIN_S1:
 		if (!master->cd_table.cdtab) {
 			ret = arm_smmu_alloc_cd_tables(master);
-			if (ret) {
-				master->domain = NULL;
+			if (ret)
 				goto out_list_del;
-			}
 		} else {
 			/*
 			 * arm_smmu_write_ctx_desc() relies on the entry being
@@ -2577,17 +2574,13 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 			 */
 			ret = arm_smmu_write_ctx_desc(master, IOMMU_NO_PASID,
 						      NULL);
-			if (ret) {
-				master->domain = NULL;
+			if (ret)
 				goto out_list_del;
-			}
 		}
 
 		ret = arm_smmu_write_ctx_desc(master, IOMMU_NO_PASID, &smmu_domain->cd);
-		if (ret) {
-			master->domain = NULL;
+		if (ret)
 			goto out_list_del;
-		}
 
 		arm_smmu_make_cdtable_ste(&target, master, &master->cd_table);
 		arm_smmu_install_ste_for_dev(master, &target);
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 1be0c1151c50c3..21f2f73501019a 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -695,7 +695,6 @@ struct arm_smmu_stream {
 struct arm_smmu_master {
 	struct arm_smmu_device		*smmu;
 	struct device			*dev;
-	struct arm_smmu_domain		*domain;
 	struct list_head		domain_head;
 	struct arm_smmu_stream		*streams;
 	/* Locked by the iommu core using the group mutex */
-- 
2.42.0