iommu: Add domain-attribute handlers

This patch introduces an extension to the iommu-api to get
and set attributes for an iommu_domain. Two functions are
introduced for this:

	* iommu_domain_get_attr()
	* iommu_domain_set_attr()

These functions will be used to make the iommu-api suitable
for GART-like IOMMUs and to implement hardware-specifc
api-extensions.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 8b9ded88e6f..c39972d8ded 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -344,3 +344,23 @@ int iommu_device_group(struct device *dev, unsigned int *groupid)
 	return -ENODEV;
 }
 EXPORT_SYMBOL_GPL(iommu_device_group);
+
+int iommu_domain_get_attr(struct iommu_domain *domain,
+			  enum iommu_attr attr, void *data)
+{
+	if (!domain->ops->domain_get_attr)
+		return -EINVAL;
+
+	return domain->ops->domain_get_attr(domain, attr, data);
+}
+EXPORT_SYMBOL_GPL(iommu_domain_get_attr);
+
+int iommu_domain_set_attr(struct iommu_domain *domain,
+			  enum iommu_attr attr, void *data)
+{
+	if (!domain->ops->domain_set_attr)
+		return -EINVAL;
+
+	return domain->ops->domain_set_attr(domain, attr, data);
+}
+EXPORT_SYMBOL_GPL(iommu_domain_set_attr);