[PATCH v4 1/5] vfio: implement iommu driver capabilities with an enum

[Baptiste Reynal <b.reynal@virtualopensystems.com>]

From: Antonios Motakis <a.motakis@virtualopensystems.com>

Currently a VFIO driver's IOMMU capabilities are encoded as a series of
numerical defines. Replace this with an enum for future maintainability.

Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
---
 include/uapi/linux/vfio.h | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 82889c3..5fb3d46 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -19,22 +19,20 @@
 
 /* Kernel & User level defines for VFIO IOCTLs. */
 
-/* Extensions */
-
-#define VFIO_TYPE1_IOMMU		1
-#define VFIO_SPAPR_TCE_IOMMU		2
-#define VFIO_TYPE1v2_IOMMU		3
 /*
- * IOMMU enforces DMA cache coherence (ex. PCIe NoSnoop stripping).  This
- * capability is subject to change as groups are added or removed.
+ * Capabilities exposed by the VFIO IOMMU driver. Some capabilities are subject
+ * to change as groups are added or removed.
  */
-#define VFIO_DMA_CC_IOMMU		4
-
-/* Check if EEH is supported */
-#define VFIO_EEH			5
+enum vfio_iommu_cap {
+	VFIO_TYPE1_IOMMU = 1,
+	VFIO_SPAPR_TCE_IOMMU = 2,
+	VFIO_TYPE1v2_IOMMU = 3,
+	VFIO_DMA_CC_IOMMU = 4,		/* IOMMU enforces DMA cache coherence
+					   (ex. PCIe NoSnoop stripping) */
+	VFIO_EEH = 5,			/* Check if EEH is supported */
+	VFIO_TYPE1_NESTING_IOMMU = 6,	/* Two-stage IOMMU, implies v2  */
+};
 
-/* Two-stage IOMMU */
-#define VFIO_TYPE1_NESTING_IOMMU	6	/* Implies v2 */
 
 /*
  * The IOCTL interface is designed for extensibility by embedding the
-- 
2.3.1