[PATCH 1/5] Revert "iommu/vt-d: Fix possible recursive lock in iommu_flush_dev_iotlb()"

[Lucas De Marchi]

This reverts commit 27d3412f05c99bf4022fffdd26abccbd6b16d861.
---
 drivers/iommu/intel/iommu.c | 39 +++++++++++++++----------------------
 1 file changed, 16 insertions(+), 23 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 0c32ad4deea7..a3f1b53909d2 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -503,9 +503,8 @@ static int domain_update_device_node(struct dmar_domain *domain)
 {
 	struct device_domain_info *info;
 	int nid = NUMA_NO_NODE;
-	unsigned long flags;
 
-	spin_lock_irqsave(&domain->lock, flags);
+	spin_lock(&domain->lock);
 	list_for_each_entry(info, &domain->devices, link) {
 		/*
 		 * There could possibly be multiple device numa nodes as devices
@@ -517,7 +516,7 @@ static int domain_update_device_node(struct dmar_domain *domain)
 		if (nid != NUMA_NO_NODE)
 			break;
 	}
-	spin_unlock_irqrestore(&domain->lock, flags);
+	spin_unlock(&domain->lock);
 
 	return nid;
 }
@@ -1344,20 +1343,19 @@ iommu_support_dev_iotlb(struct dmar_domain *domain, struct intel_iommu *iommu,
 			u8 bus, u8 devfn)
 {
 	struct device_domain_info *info;
-	unsigned long flags;
 
 	if (!iommu->qi)
 		return NULL;
 
-	spin_lock_irqsave(&domain->lock, flags);
+	spin_lock(&domain->lock);
 	list_for_each_entry(info, &domain->devices, link) {
 		if (info->iommu == iommu && info->bus == bus &&
 		    info->devfn == devfn) {
-			spin_unlock_irqrestore(&domain->lock, flags);
+			spin_unlock(&domain->lock);
 			return info->ats_supported ? info : NULL;
 		}
 	}
-	spin_unlock_irqrestore(&domain->lock, flags);
+	spin_unlock(&domain->lock);
 
 	return NULL;
 }
@@ -1366,9 +1364,8 @@ static void domain_update_iotlb(struct dmar_domain *domain)
 {
 	struct device_domain_info *info;
 	bool has_iotlb_device = false;
-	unsigned long flags;
 
-	spin_lock_irqsave(&domain->lock, flags);
+	spin_lock(&domain->lock);
 	list_for_each_entry(info, &domain->devices, link) {
 		if (info->ats_enabled) {
 			has_iotlb_device = true;
@@ -1376,7 +1373,7 @@ static void domain_update_iotlb(struct dmar_domain *domain)
 		}
 	}
 	domain->has_iotlb_device = has_iotlb_device;
-	spin_unlock_irqrestore(&domain->lock, flags);
+	spin_unlock(&domain->lock);
 }
 
 static void iommu_enable_dev_iotlb(struct device_domain_info *info)
@@ -1468,15 +1465,14 @@ static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
 				  u64 addr, unsigned mask)
 {
 	struct device_domain_info *info;
-	unsigned long flags;
 
 	if (!domain->has_iotlb_device)
 		return;
 
-	spin_lock_irqsave(&domain->lock, flags);
+	spin_lock(&domain->lock);
 	list_for_each_entry(info, &domain->devices, link)
 		__iommu_flush_dev_iotlb(info, addr, mask);
-	spin_unlock_irqrestore(&domain->lock, flags);
+	spin_unlock(&domain->lock);
 }
 
 static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,
@@ -2431,7 +2427,6 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev)
 {
 	struct device_domain_info *info = dev_iommu_priv_get(dev);
 	struct intel_iommu *iommu;
-	unsigned long flags;
 	u8 bus, devfn;
 	int ret;
 
@@ -2443,9 +2438,9 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev)
 	if (ret)
 		return ret;
 	info->domain = domain;
-	spin_lock_irqsave(&domain->lock, flags);
+	spin_lock(&domain->lock);
 	list_add(&info->link, &domain->devices);
-	spin_unlock_irqrestore(&domain->lock, flags);
+	spin_unlock(&domain->lock);
 
 	/* PASID table is mandatory for a PCI device in scalable mode. */
 	if (sm_supported(iommu) && !dev_is_real_dma_subdevice(dev)) {
@@ -4083,7 +4078,6 @@ static void dmar_remove_one_dev_info(struct device *dev)
 	struct device_domain_info *info = dev_iommu_priv_get(dev);
 	struct dmar_domain *domain = info->domain;
 	struct intel_iommu *iommu = info->iommu;
-	unsigned long flags;
 
 	if (!dev_is_real_dma_subdevice(info->dev)) {
 		if (dev_is_pci(info->dev) && sm_supported(iommu))
@@ -4095,9 +4089,9 @@ static void dmar_remove_one_dev_info(struct device *dev)
 		intel_pasid_free_table(info->dev);
 	}
 
-	spin_lock_irqsave(&domain->lock, flags);
+	spin_lock(&domain->lock);
 	list_del(&info->link);
-	spin_unlock_irqrestore(&domain->lock, flags);
+	spin_unlock(&domain->lock);
 
 	domain_detach_iommu(domain, iommu);
 	info->domain = NULL;
@@ -4416,20 +4410,19 @@ static void domain_set_force_snooping(struct dmar_domain *domain)
 static bool intel_iommu_enforce_cache_coherency(struct iommu_domain *domain)
 {
 	struct dmar_domain *dmar_domain = to_dmar_domain(domain);
-	unsigned long flags;
 
 	if (dmar_domain->force_snooping)
 		return true;
 
-	spin_lock_irqsave(&dmar_domain->lock, flags);
+	spin_lock(&dmar_domain->lock);
 	if (!domain_support_force_snooping(dmar_domain)) {
-		spin_unlock_irqrestore(&dmar_domain->lock, flags);
+		spin_unlock(&dmar_domain->lock);
 		return false;
 	}
 
 	domain_set_force_snooping(dmar_domain);
 	dmar_domain->force_snooping = true;
-	spin_unlock_irqrestore(&dmar_domain->lock, flags);
+	spin_unlock(&dmar_domain->lock);
 
 	return true;
 }
-- 
2.37.2