[PATCH v9 3/7] iommu/uapi: Introduce enum type for PASID data format

[Jacob Pan <jacob.pan.linux@gmail.com>]

There can be multiple vendor-specific PASID data formats used in UAPI
structures. This patch adds enum type with a last entry which makes
range checking much easier.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
 include/uapi/linux/iommu.h | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
index b42acc8fe007..7cc6ee6c41f7 100644
--- a/include/uapi/linux/iommu.h
+++ b/include/uapi/linux/iommu.h
@@ -298,11 +298,16 @@ struct iommu_gpasid_bind_data_vtd {
 					 IOMMU_SVA_VTD_GPASID_PCD |  \
 					 IOMMU_SVA_VTD_GPASID_PWT)
 
+enum iommu_pasid_data_format {
+	IOMMU_PASID_FORMAT_INTEL_VTD = 1,
+	IOMMU_PASID_FORMAT_LAST,
+};
+
 /**
  * struct iommu_gpasid_bind_data - Information about device and guest PASID binding
  * @argsz:	User filled size of this data
  * @version:	Version of this data structure
- * @format:	PASID table entry format
+ * @format:	PASID table entry format of enum iommu_pasid_data_format type
  * @flags:	Additional information on guest bind request
  * @gpgd:	Guest page directory base of the guest mm to bind
  * @hpasid:	Process address space ID used for the guest mm in host IOMMU
@@ -321,7 +326,6 @@ struct iommu_gpasid_bind_data {
 	__u32 argsz;
 #define IOMMU_GPASID_BIND_VERSION_1	1
 	__u32 version;
-#define IOMMU_PASID_FORMAT_INTEL_VTD	1
 	__u32 format;
 	__u32 addr_width;
 #define IOMMU_SVA_GPASID_VAL	(1 << 0) /* guest PASID valid */
-- 
2.7.4