void iommu_release_device(struct device *dev)
{
+ struct iommu_group *group = dev->iommu_group;
+ struct group_device *device;
const struct iommu_ops *ops;
- if (!dev->iommu)
+ if (!dev->iommu || !group)
return;
iommu_device_unlink(dev->iommu->iommu_dev, dev);
+ mutex_lock(&group->mutex);
+ device = __iommu_group_remove_device(group, dev);
+
+ /*
+ * If the group has become empty then ownership must have been released,
+ * and the current domain must be set back to NULL or the default
+ * domain.
+ */
+ if (list_empty(&group->devices))
+ WARN_ON(group->owner_cnt ||
+ group->domain != group->default_domain);
+
+ /*
+ * release_device() must stop using any attached domain on the device.
+ * If there are still other devices in the group they are not effected
+ * by this callback.
+ *
+ * The IOMMU driver must set the device to either an identity or
+ * blocking translation and stop using any domain pointer, as it is
+ * going to be freed.
+ */
ops = dev_iommu_ops(dev);
if (ops->release_device)
ops->release_device(dev);
+ mutex_unlock(&group->mutex);
+
+ if (device)
+ __iommu_group_release_device(group, device);
- iommu_group_remove_device(dev);
module_put(ops->owner);
dev_iommu_free(dev);
}