[PATCH v12 10/17] iommu/vt-d: Add SVA domain support

[Lu Baolu]

Add support for SVA domain allocation and provide an SVA-specific
iommu_domain_ops. This implementation is based on the existing SVA
code. Possible cleanup and refactoring are left for incremental
changes later.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Reviewed-by: Yi Liu <yi.l.liu@xxxxxxxxx>
Tested-by: Tony Zhu <tony.zhu@xxxxxxxxx>
---
 drivers/iommu/intel/iommu.h |  9 +++++++
 drivers/iommu/intel/iommu.c | 20 +++++++++++++++-
 drivers/iommu/intel/svm.c   | 47 +++++++++++++++++++++++++++++++++++++
 3 files changed, 75 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index 91312aabdd53..4ab535ec6191 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -751,6 +751,8 @@ void intel_svm_unbind(struct iommu_sva *handle);
 u32 intel_svm_get_pasid(struct iommu_sva *handle);
 int intel_svm_page_response(struct device *dev, struct iommu_fault_event *evt,
 			    struct iommu_page_response *msg);
+struct iommu_domain *intel_svm_domain_alloc(void);
+void intel_svm_block_dev_pasid(struct device *dev, ioasid_t pasid);
 
 struct intel_svm_dev {
 	struct list_head list;
@@ -776,6 +778,13 @@ struct intel_svm {
 };
 #else
 static inline void intel_svm_check(struct intel_iommu *iommu) {}
+static inline struct iommu_domain *intel_svm_domain_alloc(void)
+{
+	return NULL;
+}
+static inline void intel_svm_block_dev_pasid(struct device *dev, ioasid_t pasid)
+{
+}
 #endif
 
 #ifdef CONFIG_INTEL_IOMMU_DEBUGFS
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index ffd1ff69bf25..d242911f0a88 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4137,9 +4137,25 @@ static int blocking_domain_attach_dev(struct iommu_domain *domain,
 	return 0;
 }
 
+static int blocking_domain_set_dev_pasid(struct iommu_domain *_domain,
+					 struct device *dev, ioasid_t pasid)
+{
+	struct iommu_domain *domain;
+
+	domain = iommu_get_domain_for_dev_pasid(dev, pasid, IOMMU_DOMAIN_SVA);
+	if (IS_ERR(domain))
+		return PTR_ERR(domain);
+
+	if (domain)
+		intel_svm_block_dev_pasid(dev, pasid);
+
+	return 0;
+}
+
 static struct iommu_domain blocking_domain = {
 	.ops = &(const struct iommu_domain_ops) {
-		.attach_dev	= blocking_domain_attach_dev
+		.attach_dev	= blocking_domain_attach_dev,
+		.set_dev_pasid	= blocking_domain_set_dev_pasid,
 	}
 };
 
@@ -4174,6 +4190,8 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type)
 		return domain;
 	case IOMMU_DOMAIN_IDENTITY:
 		return &si_domain->domain;
+	case IOMMU_DOMAIN_SVA:
+		return intel_svm_domain_alloc();
 	default:
 		return NULL;
 	}
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 2420fa5c2360..a71ad7aa6578 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -928,3 +928,50 @@ int intel_svm_page_response(struct device *dev,
 	mutex_unlock(&pasid_mutex);
 	return ret;
 }
+
+void intel_svm_block_dev_pasid(struct device *dev, ioasid_t pasid)
+{
+	mutex_lock(&pasid_mutex);
+	intel_svm_unbind_mm(dev, pasid);
+	mutex_unlock(&pasid_mutex);
+}
+
+static int intel_svm_set_dev_pasid(struct iommu_domain *domain,
+				   struct device *dev, ioasid_t pasid)
+{
+	struct device_domain_info *info = dev_iommu_priv_get(dev);
+	struct intel_iommu *iommu = info->iommu;
+	struct mm_struct *mm = domain->mm;
+	struct iommu_sva *sva;
+	int ret = 0;
+
+	mutex_lock(&pasid_mutex);
+	sva = intel_svm_bind_mm(iommu, dev, mm);
+	if (IS_ERR(sva))
+		ret = PTR_ERR(sva);
+	mutex_unlock(&pasid_mutex);
+
+	return ret;
+}
+
+static void intel_svm_domain_free(struct iommu_domain *domain)
+{
+	kfree(to_dmar_domain(domain));
+}
+
+static const struct iommu_domain_ops intel_svm_domain_ops = {
+	.set_dev_pasid		= intel_svm_set_dev_pasid,
+	.free			= intel_svm_domain_free
+};
+
+struct iommu_domain *intel_svm_domain_alloc(void)
+{
+	struct dmar_domain *domain;
+
+	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+	if (!domain)
+		return NULL;
+	domain->domain.ops = &intel_svm_domain_ops;
+
+	return &domain->domain;
+}
-- 
2.25.1