@@ -2893,6 +2893,24 @@ void iommu_detach_subdev_group(struct iommu_domain *domain,
}
EXPORT_SYMBOL_GPL(iommu_detach_subdev_group);
+struct iommu_domain *iommu_aux_get_domain_for_dev(struct device *subdev)
+{
+ struct iommu_domain *domain = NULL;
+ struct iommu_group *group;
+
+ group = iommu_group_get(subdev);
+ if (!group || !group->domain)
+ return NULL;
+
+ if (domain_is_aux(group->domain, subdev))
+ domain = group->domain;
+
+ iommu_group_put(group);
+
+ return domain;
+}
+EXPORT_SYMBOL_GPL(iommu_aux_get_domain_for_dev);
+
/**
* iommu_sva_bind_device() - Bind a process address space to a device
* @dev: the device
@@ -120,6 +120,7 @@ enum iommu_attr {
DOMAIN_ATTR_NESTING, /* two stages of translation */
DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE,
DOMAIN_ATTR_MAX,
+ DOMAIN_ATTR_IS_AUX,
};
/* These are the possible reserved region types */
@@ -622,6 +623,12 @@ static inline void dev_iommu_priv_set(struct device *dev, void *priv)
dev->iommu->priv = priv;
}
+static inline bool
+domain_is_aux(struct iommu_domain *domain, struct device *subdev)
+{
+ return iommu_domain_get_attr(domain, DOMAIN_ATTR_IS_AUX, subdev);
+}
+
int iommu_probe_device(struct device *dev);
void iommu_release_device(struct device *dev);
@@ -638,6 +645,7 @@ int iommu_attach_subdev_group(struct iommu_domain *domain,
void iommu_detach_subdev_group(struct iommu_domain *domain,
struct iommu_group *group,
iommu_device_lookup_t fn);
+struct iommu_domain *iommu_aux_get_domain_for_dev(struct device *subdev);
struct iommu_sva *iommu_sva_bind_device(struct device *dev,
struct mm_struct *mm,
@@ -1039,6 +1047,18 @@ iommu_detach_subdev_group(struct iommu_domain *domain, struct iommu_group *group
{
}
+static inline bool
+domain_is_aux(struct iommu_domain *domain, struct device *subdev)
+{
+ return false;
+}
+
+static inline struct iommu_domain *
+iommu_aux_get_domain_for_dev(struct device *subdev)
+{
+ return NULL;
+}
+
static inline struct iommu_sva *
iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void *drvdata)
{
The device driver needs an API to get its aux-domain. A typical usage scenario is: unsigned long pasid; struct iommu_domain *domain; struct device *dev = mdev_dev(mdev); struct device *iommu_device = vfio_mdev_get_iommu_device(dev); domain = iommu_aux_get_domain_for_dev(dev); if (!domain) return -ENODEV; pasid = iommu_aux_get_pasid(domain, iommu_device); if (pasid <= 0) return -EINVAL; /* Program the device context */ .... This adds an API for such use case. Suggested-by: Alex Williamson <alex.williamson@redhat.com> Link: https://lore.kernel.org/linux-iommu/20200708130749.1b1e1421@x1.home/ Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> --- drivers/iommu/iommu.c | 18 ++++++++++++++++++ include/linux/iommu.h | 20 ++++++++++++++++++++ 2 files changed, 38 insertions(+)