iommu: Add iommu_get_domain_for_dev function
This function can be used to request the current domain a
device is attached to.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 7bce522..a0a38bd 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1076,6 +1076,24 @@
}
EXPORT_SYMBOL_GPL(iommu_detach_device);
+struct iommu_domain *iommu_get_domain_for_dev(struct device *dev)
+{
+ struct iommu_domain *domain;
+ struct iommu_group *group;
+
+ group = iommu_group_get(dev);
+ /* FIXME: Remove this when groups a mandatory for iommu drivers */
+ if (group == NULL)
+ return NULL;
+
+ domain = group->domain;
+
+ iommu_group_put(group);
+
+ return domain;
+}
+EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev);
+
/*
* IOMMU groups are really the natrual working unit of the IOMMU, but
* the IOMMU API works on domains and devices. Bridge that gap by