Commit 969aaefb authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Use device_domain_lock accurately 



The device_domain_lock is used to protect the device tracking list of
a domain. Remove unnecessary spin_lock/unlock()'s and move the necessary
ones around the list access.

Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220706025524.2904370-11-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent db75c957

drivers/iommu/intel/iommu.c

+19 −38
Original line number Diff line number Diff line
@@ -535,15 +535,8 @@ static int domain_update_device_node(struct dmar_domain *domain) 
	struct device_domain_info *info;

	int nid = NUMA_NO_NODE;



	assert_spin_locked(&device_domain_lock);



	if (list_empty(&domain->devices))

		return NUMA_NO_NODE;



	spin_lock(&device_domain_lock);

	list_for_each_entry(info, &domain->devices, link) {

		if (!info->dev)

			continue;



		/*

		 * There could possibly be multiple device numa nodes as devices

		 * within the same domain may sit behind different IOMMUs. There
@@ -554,6 +547,7 @@ static int domain_update_device_node(struct dmar_domain *domain) 
		if (nid != NUMA_NO_NODE)

			break;

	}

	spin_unlock(&device_domain_lock);



	return nid;

}
@@ -1381,18 +1375,18 @@ iommu_support_dev_iotlb (struct dmar_domain *domain, struct intel_iommu *iommu, 
{

	struct device_domain_info *info;



	assert_spin_locked(&device_domain_lock);



	if (!iommu->qi)

		return NULL;



	list_for_each_entry(info, &domain->devices, link)

	spin_lock(&device_domain_lock);

	list_for_each_entry(info, &domain->devices, link) {

		if (info->iommu == iommu && info->bus == bus &&

		    info->devfn == devfn) {

			if (info->ats_supported && info->dev)

				return info;

			break;

			spin_unlock(&device_domain_lock);

			return info->ats_supported ? info : NULL;

		}

	}

	spin_unlock(&device_domain_lock);



	return NULL;

}
@@ -1402,23 +1396,21 @@ static void domain_update_iotlb(struct dmar_domain *domain) 
	struct device_domain_info *info;

	bool has_iotlb_device = false;



	assert_spin_locked(&device_domain_lock);



	list_for_each_entry(info, &domain->devices, link)

	spin_lock(&device_domain_lock);

	list_for_each_entry(info, &domain->devices, link) {

		if (info->ats_enabled) {

			has_iotlb_device = true;

			break;

		}



	}

	domain->has_iotlb_device = has_iotlb_device;

	spin_unlock(&device_domain_lock);

}



static void iommu_enable_dev_iotlb(struct device_domain_info *info)

{

	struct pci_dev *pdev;



	assert_spin_locked(&device_domain_lock);



	if (!info || !dev_is_pci(info->dev))

		return;
@@ -1464,8 +1456,6 @@ static void iommu_disable_dev_iotlb(struct device_domain_info *info) 
{

	struct pci_dev *pdev;



	assert_spin_locked(&device_domain_lock);



	if (!dev_is_pci(info->dev))

		return;
@@ -1906,9 +1896,10 @@ static int domain_context_mapping_one(struct dmar_domain *domain, 
				      struct pasid_table *table,

				      u8 bus, u8 devfn)

{

	struct device_domain_info *info =

			iommu_support_dev_iotlb(domain, iommu, bus, devfn);

	u16 did = domain->iommu_did[iommu->seq_id];

	int translation = CONTEXT_TT_MULTI_LEVEL;

	struct device_domain_info *info = NULL;

	struct context_entry *context;

	int ret;
@@ -1922,9 +1913,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain, 


	BUG_ON(!domain->pgd);



	spin_lock(&device_domain_lock);

	spin_lock(&iommu->lock);



	ret = -ENOMEM;

	context = iommu_context_addr(iommu, bus, devfn, 1);

	if (!context)
@@ -1975,7 +1964,6 @@ static int domain_context_mapping_one(struct dmar_domain *domain, 
		 * Setup the Device-TLB enable bit and Page request

		 * Enable bit:

		 */

		info = iommu_support_dev_iotlb(domain, iommu, bus, devfn);

		if (info && info->ats_supported)

			context_set_sm_dte(context);

		if (info && info->pri_supported)
@@ -1998,7 +1986,6 @@ static int domain_context_mapping_one(struct dmar_domain *domain, 
					goto out_unlock;

			}



			info = iommu_support_dev_iotlb(domain, iommu, bus, devfn);

			if (info && info->ats_supported)

				translation = CONTEXT_TT_DEV_IOTLB;

			else
@@ -2044,7 +2031,6 @@ static int domain_context_mapping_one(struct dmar_domain *domain, 


out_unlock:

	spin_unlock(&iommu->lock);

	spin_unlock(&device_domain_lock);



	return ret;

}
@@ -2456,13 +2442,11 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev) 
	if (!iommu)

		return -ENODEV;



	spin_lock(&device_domain_lock);

	info->domain = domain;

	ret = domain_attach_iommu(domain, iommu);

	if (ret) {

		spin_unlock(&device_domain_lock);

	if (ret)

		return ret;

	}

	info->domain = domain;

	spin_lock(&device_domain_lock);

	list_add(&info->link, &domain->devices);

	spin_unlock(&device_domain_lock);
@@ -4638,9 +4622,7 @@ int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct device *dev) 
	if (!domain)

		return -EINVAL;



	spin_lock(&device_domain_lock);

	spin_lock(&iommu->lock);



	ret = -EINVAL;

	if (!info->pasid_supported)

		goto out;
@@ -4670,7 +4652,6 @@ int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct device *dev) 


 out:

	spin_unlock(&iommu->lock);

	spin_unlock(&device_domain_lock);



	return ret;

}