Driver core: Add iommu_ops to bus_type

This is the starting point to make the iommu_ops used for
the iommu-api a per-bus-type structure. It is required to
easily implement bus-specific setup in the iommu-layer.
The first user will be the iommu-group attribute in sysfs.

Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

2 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index c20dfbfc49b4..e838e143baa7 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -33,6 +33,7 @@ struct class;
 struct subsys_private;
 struct bus_type;
 struct device_node;
+struct iommu_ops;
 
 struct bus_attribute {
 	struct attribute	attr;
@@ -67,6 +68,9 @@ extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
  * @resume:	Called to bring a device on this bus out of sleep mode.
  * @pm:		Power management operations of this bus, callback the specific
  *		device driver's pm-ops.
+ * @iommu_ops   IOMMU specific operations for this bus, used to attach IOMMU
+ *              driver implementations to a bus and allow the driver to do
+ *              bus-specific setup
  * @p:		The private data of the driver core, only the driver core can
  *		touch this.
  *
@@ -96,6 +100,8 @@ struct bus_type {
 
 	const struct dev_pm_ops *pm;
 
+	struct iommu_ops *iommu_ops;
+
 	struct subsys_private *p;
 };
 
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 6470cd87b4ea..dca83d3405b1 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -25,6 +25,7 @@
 #define IOMMU_WRITE	(2)
 #define IOMMU_CACHE	(4) /* DMA cache coherency */
 
+struct bus_type;
 struct device;
 
 struct iommu_domain {
@@ -52,6 +53,7 @@ struct iommu_ops {
 };
 
 extern void register_iommu(struct iommu_ops *ops);
+extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
 extern bool iommu_found(void);
 extern struct iommu_domain *iommu_domain_alloc(void);
 extern void iommu_domain_free(struct iommu_domain *domain);