[PATCH] vfio: re-arrange vfio region definitions

[Cornelia Huck]

It is easy to miss already defined region types. Let's re-arrange
the definitions a bit and add more comments to make it hopefully
a bit clearer.

No functional change.

Signed-off-by: Cornelia Huck <cohuck@xxxxxxxxxx>
---
 include/uapi/linux/vfio.h | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 8f10748dac79..d9bcf40240be 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -295,15 +295,23 @@ struct vfio_region_info_cap_type {
 	__u32 subtype;	/* type specific */
 };
 
+/*
+ * List of region types, global per bus driver.
+ * If you introduce a new type, please add it here.
+ */
+
+/* PCI region type containing a PCI vendor part */
 #define VFIO_REGION_TYPE_PCI_VENDOR_TYPE	(1 << 31)
 #define VFIO_REGION_TYPE_PCI_VENDOR_MASK	(0xffff)
+#define VFIO_REGION_TYPE_GFX                    (1)
+#define VFIO_REGION_TYPE_CCW			(2)
 
-/* 8086 Vendor sub-types */
+/* 8086 vendor PCI sub-types */
 #define VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION	(1)
 #define VFIO_REGION_SUBTYPE_INTEL_IGD_HOST_CFG	(2)
 #define VFIO_REGION_SUBTYPE_INTEL_IGD_LPC_CFG	(3)
 
-#define VFIO_REGION_TYPE_GFX                    (1)
+/* GFX sub-types */
 #define VFIO_REGION_SUBTYPE_GFX_EDID            (1)
 
 /**
@@ -353,20 +361,17 @@ struct vfio_region_gfx_edid {
 #define VFIO_DEVICE_GFX_LINK_STATE_DOWN  2
 };
 
-#define VFIO_REGION_TYPE_CCW			(2)
 /* ccw sub-types */
 #define VFIO_REGION_SUBTYPE_CCW_ASYNC_CMD	(1)
 
+/* 10de vendor PCI sub-types */
 /*
- * 10de vendor sub-type
- *
  * NVIDIA GPU NVlink2 RAM is coherent RAM mapped onto the host address space.
  */
 #define VFIO_REGION_SUBTYPE_NVIDIA_NVLINK2_RAM	(1)
 
+/* 1014 vendor PCI sub-types*/
 /*
- * 1014 vendor sub-type
- *
  * IBM NPU NVlink2 ATSD (Address Translation Shootdown) register of NPU
  * to do TLB invalidation on a GPU.
  */
-- 
2.20.1