@@ -699,6 +699,10 @@ u32 iommu_sva_get_pasid(struct iommu_sva *handle);
int iommu_device_set_dma_owner(struct device *dev, enum iommu_dma_owner owner,
void *owner_cookie);
void iommu_device_release_dma_owner(struct device *dev, enum iommu_dma_owner owner);
+int iommu_group_set_dma_owner(struct iommu_group *group, enum iommu_dma_owner owner,
+ void *owner_cookie);
+void iommu_group_release_dma_owner(struct iommu_group *group, enum iommu_dma_owner owner);
+bool iommu_group_dma_owner_unclaimed(struct iommu_group *group);
#else /* CONFIG_IOMMU_API */
@@ -1115,6 +1119,23 @@ static inline void iommu_device_release_dma_owner(struct device *dev,
enum iommu_dma_owner owner)
{
}
+
+static inline int iommu_group_set_dma_owner(struct iommu_group *group,
+ enum iommu_dma_owner owner,
+ void *owner_cookie)
+{
+ return -EINVAL;
+}
+
+static inline void iommu_group_release_dma_owner(struct iommu_group *group,
+ enum iommu_dma_owner owner)
+{
+}
+
+static inline bool iommu_group_dma_owner_unclaimed(struct iommu_group *group)
+{
+ return false;
+}
#endif /* CONFIG_IOMMU_API */
/**
@@ -3365,9 +3365,19 @@ static ssize_t iommu_group_store_type(struct iommu_group *group,
return ret;
}
-static int iommu_group_set_dma_owner(struct iommu_group *group,
- enum iommu_dma_owner owner,
- void *owner_cookie)
+/**
+ * iommu_group_set_dma_owner() - Set DMA ownership of a group
+ * @group: The group.
+ * @owner: DMA owner type.
+ * @owner_cookie: Caller specified pointer. Could be used for exclusive
+ * declaration. Could be NULL.
+ *
+ * This is to support backward compatibility for legacy vfio which manages
+ * dma ownership in group level. New invocations on this interface should be
+ * prohibited. Instead, please turn to iommu_device_set_dma_owner().
+ */
+int iommu_group_set_dma_owner(struct iommu_group *group, enum iommu_dma_owner owner,
+ void *owner_cookie)
{
int ret = 0;
@@ -3398,9 +3408,16 @@ static int iommu_group_set_dma_owner(struct iommu_group *group,
return ret;
}
+EXPORT_SYMBOL_GPL(iommu_group_set_dma_owner);
-static void iommu_group_release_dma_owner(struct iommu_group *group,
- enum iommu_dma_owner owner)
+/**
+ * iommu_group_release_dma_owner() - Release DMA ownership of a group
+ * @group: The group.
+ * @owner: DMA owner type.
+ *
+ * Release the DMA ownership claimed by iommu_group_set_dma_owner().
+ */
+void iommu_group_release_dma_owner(struct iommu_group *group, enum iommu_dma_owner owner)
{
mutex_lock(&group->mutex);
if (WARN_ON(!group->owner_cnt || group->dma_owner != owner))
@@ -3423,6 +3440,26 @@ static void iommu_group_release_dma_owner(struct iommu_group *group,
unlock_out:
mutex_unlock(&group->mutex);
}
+EXPORT_SYMBOL_GPL(iommu_group_release_dma_owner);
+
+/**
+ * iommu_group_dma_owner_unclaimed() - Is group dma ownership claimed
+ * @group: The group.
+ *
+ * This provides status check on a given group. It is racey and only for
+ * non-binding status reporting.
+ */
+bool iommu_group_dma_owner_unclaimed(struct iommu_group *group)
+{
+ unsigned int user;
+
+ mutex_lock(&group->mutex);
+ user = group->owner_cnt;
+ mutex_unlock(&group->mutex);
+
+ return !user;
+}
+EXPORT_SYMBOL_GPL(iommu_group_dma_owner_unclaimed);
/**
* iommu_device_set_dma_owner() - Set DMA ownership of a device
The vfio needs to set DMA_OWNER_PRIVATE_DOMAIN_USER for the entire group when attaching it to a vfio container. Expose group variants of setting/ releasing dma ownership for this purpose. This also exposes the helper iommu_group_dma_owner_unclaimed() for vfio to report to userspace if the group is viable to user assignment for compatibility with VFIO_GROUP_FLAGS_VIABLE. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> --- include/linux/iommu.h | 21 +++++++++++++++++++ drivers/iommu/iommu.c | 47 ++++++++++++++++++++++++++++++++++++++----- 2 files changed, 63 insertions(+), 5 deletions(-)