1 files changed, 43 insertions, 28 deletions

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
index 8a16cd3ef487..353248ab18e7 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
@@ -25,11 +25,9 @@ struct arm_smmu_mmu_notifier {
 #define mn_to_smmu(mn) container_of(mn, struct arm_smmu_mmu_notifier, mn)
 
 struct arm_smmu_bond {
-	struct iommu_sva		sva;
 	struct mm_struct		*mm;
 	struct arm_smmu_mmu_notifier	*smmu_mn;
 	struct list_head		list;
-	refcount_t			refs;
 };
 
 #define sva_to_bond(handle) \
@@ -38,6 +36,25 @@ struct arm_smmu_bond {
 static DEFINE_MUTEX(sva_lock);
 
 /*
+ * Write the CD to the CD tables for all masters that this domain is attached
+ * to. Note that this is only used to update existing CD entries in the target
+ * CD table, for which it's assumed that arm_smmu_write_ctx_desc can't fail.
+ */
+static void arm_smmu_update_ctx_desc_devices(struct arm_smmu_domain *smmu_domain,
+					   int ssid,
+					   struct arm_smmu_ctx_desc *cd)
+{
+	struct arm_smmu_master *master;
+	unsigned long flags;
+
+	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+	list_for_each_entry(master, &smmu_domain->devices, domain_head) {
+		arm_smmu_write_ctx_desc(master, ssid, cd);
+	}
+	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+}
+
+/*
  * Check if the CPU ASID is available on the SMMU side. If a private context
  * descriptor is using it, try to replace it.
  */
@@ -62,7 +79,7 @@ arm_smmu_share_asid(struct mm_struct *mm, u16 asid)
 		return cd;
 	}
 
-	smmu_domain = container_of(cd, struct arm_smmu_domain, s1_cfg.cd);
+	smmu_domain = container_of(cd, struct arm_smmu_domain, cd);
 	smmu = smmu_domain->smmu;
 
 	ret = xa_alloc(&arm_smmu_asid_xa, &new_asid, cd,
@@ -80,7 +97,7 @@ arm_smmu_share_asid(struct mm_struct *mm, u16 asid)
 	 * be some overlap between use of both ASIDs, until we invalidate the
 	 * TLB.
 	 */
-	arm_smmu_write_ctx_desc(smmu_domain, IOMMU_NO_PASID, cd);
+	arm_smmu_update_ctx_desc_devices(smmu_domain, IOMMU_NO_PASID, cd);
 
 	/* Invalidate TLB entries previously associated with that context */
 	arm_smmu_tlb_inv_asid(smmu, asid);
@@ -247,7 +264,7 @@ static void arm_smmu_mm_release(struct mmu_notifier *mn, struct mm_struct *mm)
 	 * DMA may still be running. Keep the cd valid to avoid C_BAD_CD events,
 	 * but disable translation.
 	 */
-	arm_smmu_write_ctx_desc(smmu_domain, mm->pasid, &quiet_cd);
+	arm_smmu_update_ctx_desc_devices(smmu_domain, mm->pasid, &quiet_cd);
 
 	arm_smmu_tlb_inv_asid(smmu_domain->smmu, smmu_mn->cd->asid);
 	arm_smmu_atc_inv_domain(smmu_domain, mm->pasid, 0, 0);
@@ -273,8 +290,10 @@ arm_smmu_mmu_notifier_get(struct arm_smmu_domain *smmu_domain,
 			  struct mm_struct *mm)
 {
 	int ret;
+	unsigned long flags;
 	struct arm_smmu_ctx_desc *cd;
 	struct arm_smmu_mmu_notifier *smmu_mn;
+	struct arm_smmu_master *master;
 
 	list_for_each_entry(smmu_mn, &smmu_domain->mmu_notifiers, list) {
 		if (smmu_mn->mn.mm == mm) {
@@ -304,7 +323,16 @@ arm_smmu_mmu_notifier_get(struct arm_smmu_domain *smmu_domain,
 		goto err_free_cd;
 	}
 
-	ret = arm_smmu_write_ctx_desc(smmu_domain, mm->pasid, cd);
+	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+	list_for_each_entry(master, &smmu_domain->devices, domain_head) {
+		ret = arm_smmu_write_ctx_desc(master, mm->pasid, cd);
+		if (ret) {
+			list_for_each_entry_from_reverse(master, &smmu_domain->devices, domain_head)
+				arm_smmu_write_ctx_desc(master, mm->pasid, NULL);
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
 	if (ret)
 		goto err_put_notifier;
 
@@ -329,7 +357,8 @@ static void arm_smmu_mmu_notifier_put(struct arm_smmu_mmu_notifier *smmu_mn)
 		return;
 
 	list_del(&smmu_mn->list);
-	arm_smmu_write_ctx_desc(smmu_domain, mm->pasid, NULL);
+
+	arm_smmu_update_ctx_desc_devices(smmu_domain, mm->pasid, NULL);
 
 	/*
 	 * If we went through clear(), we've already invalidated, and no
@@ -345,8 +374,7 @@ static void arm_smmu_mmu_notifier_put(struct arm_smmu_mmu_notifier *smmu_mn)
 	arm_smmu_free_shared_cd(cd);
 }
 
-static struct iommu_sva *
-__arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
+static int __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
 {
 	int ret;
 	struct arm_smmu_bond *bond;
@@ -355,23 +383,13 @@ __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 
 	if (!master || !master->sva_enabled)
-		return ERR_PTR(-ENODEV);
-
-	/* If bind() was already called for this {dev, mm} pair, reuse it. */
-	list_for_each_entry(bond, &master->bonds, list) {
-		if (bond->mm == mm) {
-			refcount_inc(&bond->refs);
-			return &bond->sva;
-		}
-	}
+		return -ENODEV;
 
 	bond = kzalloc(sizeof(*bond), GFP_KERNEL);
 	if (!bond)
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 
 	bond->mm = mm;
-	bond->sva.dev = dev;
-	refcount_set(&bond->refs, 1);
 
 	bond->smmu_mn = arm_smmu_mmu_notifier_get(smmu_domain, mm);
 	if (IS_ERR(bond->smmu_mn)) {
@@ -380,11 +398,11 @@ __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
 	}
 
 	list_add(&bond->list, &master->bonds);
-	return &bond->sva;
+	return 0;
 
 err_free_bond:
 	kfree(bond);
-	return ERR_PTR(ret);
+	return ret;
 }
 
 bool arm_smmu_sva_supported(struct arm_smmu_device *smmu)
@@ -550,7 +568,7 @@ void arm_smmu_sva_remove_dev_pasid(struct iommu_domain *domain,
 		}
 	}
 
-	if (!WARN_ON(!bond) && refcount_dec_and_test(&bond->refs)) {
+	if (!WARN_ON(!bond)) {
 		list_del(&bond->list);
 		arm_smmu_mmu_notifier_put(bond->smmu_mn);
 		kfree(bond);
@@ -562,13 +580,10 @@ static int arm_smmu_sva_set_dev_pasid(struct iommu_domain *domain,
 				      struct device *dev, ioasid_t id)
 {
 	int ret = 0;
-	struct iommu_sva *handle;
 	struct mm_struct *mm = domain->mm;
 
 	mutex_lock(&sva_lock);
-	handle = __arm_smmu_sva_bind(dev, mm);
-	if (IS_ERR(handle))
-		ret = PTR_ERR(handle);
+	ret = __arm_smmu_sva_bind(dev, mm);
 	mutex_unlock(&sva_lock);
 
 	return ret;