1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 109de67d5d72..344e27e8f188 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -2039,3 +2039,99 @@ int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids);
+
+/*
+ * Per device IOMMU features.
+ */
+bool iommu_dev_has_feature(struct device *dev, enum iommu_dev_features feat)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (ops && ops->dev_has_feat)
+		return ops->dev_has_feat(dev, feat);
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_has_feature);
+
+int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (ops && ops->dev_enable_feat)
+		return ops->dev_enable_feat(dev, feat);
+
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_enable_feature);
+
+/*
+ * The device drivers should do the necessary cleanups before calling this.
+ * For example, before disabling the aux-domain feature, the device driver
+ * should detach all aux-domains. Otherwise, this will return -EBUSY.
+ */
+int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (ops && ops->dev_disable_feat)
+		return ops->dev_disable_feat(dev, feat);
+
+	return -EBUSY;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_disable_feature);
+
+bool iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features feat)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (ops && ops->dev_feat_enabled)
+		return ops->dev_feat_enabled(dev, feat);
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_feature_enabled);
+
+/*
+ * Aux-domain specific attach/detach.
+ *
+ * Only works if iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX) returns
+ * true. Also, as long as domains are attached to a device through this
+ * interface, any tries to call iommu_attach_device() should fail
+ * (iommu_detach_device() can't fail, so we fail when trying to re-attach).
+ * This should make us safe against a device being attached to a guest as a
+ * whole while there are still pasid users on it (aux and sva).
+ */
+int iommu_aux_attach_device(struct iommu_domain *domain, struct device *dev)
+{
+	int ret = -ENODEV;
+
+	if (domain->ops->aux_attach_dev)
+		ret = domain->ops->aux_attach_dev(domain, dev);
+
+	if (!ret)
+		trace_attach_device_to_domain(dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_aux_attach_device);
+
+void iommu_aux_detach_device(struct iommu_domain *domain, struct device *dev)
+{
+	if (domain->ops->aux_detach_dev) {
+		domain->ops->aux_detach_dev(domain, dev);
+		trace_detach_device_from_domain(dev);
+	}
+}
+EXPORT_SYMBOL_GPL(iommu_aux_detach_device);
+
+int iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev)
+{
+	int ret = -ENODEV;
+
+	if (domain->ops->aux_get_pasid)
+		ret = domain->ops->aux_get_pasid(domain, dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_aux_get_pasid);