Re: [qemu-s390x] [PATCH 1/3] vfio-ccw: add capabilities chain

[Eric Farman]

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)