Re: [PATCH 1/3] vfio-ccw: add capabilities chain

Eric Farman
2018-12-17T21:53:34Z

On 11/22/2018 11:54 AM, Cornelia Huck wrote:

...snip...

> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> index 813102810f53..565669f95534 100644
> --- a/include/uapi/linux/vfio.h
> +++ b/include/uapi/linux/vfio.h
> @@ -297,6 +297,7 @@ struct vfio_region_info_cap_type {
>
> #define VFIO_REGION_TYPE_PCI_VENDOR_TYPE (1 << 31)
> #define VFIO_REGION_TYPE_PCI_VENDOR_MASK (0xffff)
> +#define VFIO_REGION_TYPE_CCW (1 << 30)

Oof. So the existing VFIO_REGION_TYPE_PCI_VENDOR_TYPE gets OR'd with
another value (e.g., 8086). But in 4.20, there was a
VFIO_REGION_TYPE_GFX is added as simply "1" ... Which direction are
these definitions being added from? I guess asked another way, is
_TYPE_CCW going to be OR'd with anything else that necessitates its
presence as an identifier with some Other Thing, or should this follow
the TYPE_GFX enumeration? Perhaps the type field needs to be tidied up
to help this sit more cleanly now? (Sorry!)

- Eric

>
> /* 8086 Vendor sub-types */
> #define VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION (1)
>