diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 109de67d5d727c227d3970b2879edd60d6478357..344e27e8f18822270d0d52953fbf171b823c1a17 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);
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index ffbbc7e39ceeba3ed827cc475b78683de27dc31a..8239ece9fdfc218aff0f99b1a078608ab04b58c2 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -156,6 +156,11 @@ struct iommu_resv_region {
enum iommu_resv_type type;
};
+/* Per device IOMMU features */
+enum iommu_dev_features {
+ IOMMU_DEV_FEAT_AUX, /* Aux-domain feature */
+};
+
#ifdef CONFIG_IOMMU_API
/**
@@ -186,6 +191,11 @@ struct iommu_resv_region {
* @of_xlate: add OF master IDs to iommu grouping
* @is_attach_deferred: Check if domain attach should be deferred from iommu
* driver init to device driver init (default no)
+ * @dev_has/enable/disable_feat: per device entries to check/enable/disable
+ * iommu specific features.
+ * @dev_feat_enabled: check enabled feature
+ * @aux_attach/detach_dev: aux-domain specific attach/detach entries.
+ * @aux_get_pasid: get the pasid given an aux-domain
* @pgsize_bitmap: bitmap of all possible supported page sizes
*/
struct iommu_ops {
@@ -230,6 +240,17 @@ struct iommu_ops {
int (*of_xlate)(struct device *dev, struct of_phandle_args *args);
bool (*is_attach_deferred)(struct iommu_domain *domain, struct device *dev);
+ /* Per device IOMMU features */
+ bool (*dev_has_feat)(struct device *dev, enum iommu_dev_features f);
+ bool (*dev_feat_enabled)(struct device *dev, enum iommu_dev_features f);
+ int (*dev_enable_feat)(struct device *dev, enum iommu_dev_features f);
+ int (*dev_disable_feat)(struct device *dev, enum iommu_dev_features f);
+
+ /* Aux-domain specific attach/detach entries */
+ int (*aux_attach_dev)(struct iommu_domain *domain, struct device *dev);
+ void (*aux_detach_dev)(struct iommu_domain *domain, struct device *dev);
+ int (*aux_get_pasid)(struct iommu_domain *domain, struct device *dev);
+
unsigned long pgsize_bitmap;
};
@@ -416,6 +437,14 @@ static inline void dev_iommu_fwspec_set(struct device *dev,
int iommu_probe_device(struct device *dev);
void iommu_release_device(struct device *dev);
+bool iommu_dev_has_feature(struct device *dev, enum iommu_dev_features f);
+int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features f);
+int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features f);
+bool iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features f);
+int iommu_aux_attach_device(struct iommu_domain *domain, struct device *dev);
+void iommu_aux_detach_device(struct iommu_domain *domain, struct device *dev);
+int iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev);
+
#else /* CONFIG_IOMMU_API */
struct iommu_ops {};
@@ -700,6 +729,47 @@ const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode)
return NULL;
}
+static inline bool
+iommu_dev_has_feature(struct device *dev, enum iommu_dev_features feat)
+{
+ return false;
+}
+
+static inline bool
+iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features feat)
+{
+ return false;
+}
+
+static inline int
+iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat)
+{
+ return -ENODEV;
+}
+
+static inline int
+iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat)
+{
+ return -ENODEV;
+}
+
+static inline int
+iommu_aux_attach_device(struct iommu_domain *domain, struct device *dev)
+{
+ return -ENODEV;
+}
+
+static inline void
+iommu_aux_detach_device(struct iommu_domain *domain, struct device *dev)
+{
+}
+
+static inline int
+iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev)
+{
+ return -ENODEV;
+}
+
#endif /* CONFIG_IOMMU_API */
#ifdef CONFIG_IOMMU_DEBUGFS