[PATCH v4 14/27] vfio: Add CXL region type for the HDM region

[<mhonap@nvidia.com>]

From: Manish Honap <mhonap@nvidia.com>

A CXL Type-2 device exposes its HDM memory to the guest as a dedicated
VFIO region rather than a PCI BAR. Add a CXL region type and a memory
sub-type for it; vfio-cxl registers the window under these so userspace
can discover and map it.

Signed-off-by: Manish Honap <mhonap@nvidia.com>
---
 include/uapi/linux/vfio.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 5de618a3a5ee..540e62312671 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -345,6 +345,7 @@ struct vfio_region_info_cap_type {
 #define VFIO_REGION_TYPE_GFX                    (1)
 #define VFIO_REGION_TYPE_CCW			(2)
 #define VFIO_REGION_TYPE_MIGRATION_DEPRECATED   (3)
+#define VFIO_REGION_TYPE_CXL			(4)
 
 /* sub-types for VFIO_REGION_TYPE_PCI_* */
 
@@ -373,6 +374,10 @@ struct vfio_region_info_cap_type {
 /* sub-types for VFIO_REGION_TYPE_GFX */
 #define VFIO_REGION_SUBTYPE_GFX_EDID            (1)
 
+/* sub-types for VFIO_REGION_TYPE_CXL */
+/* CXL.mem HDM region of a Type-2 device, mmap-able */
+#define VFIO_REGION_SUBTYPE_CXL_MEM		(1)
+
 /**
  * struct vfio_region_gfx_edid - EDID region layout.
  *
-- 
2.25.1