[Intel-gfx] [PATCH v16 5/6] vfio: ABI for mdev display dma-buf operation

[Gerd Hoffmann]

  Hi,

> Should we then specify the error code for "head doesn't exist" vs
> "head
> doesn't support dmabuf", with the former taking precedence?  Perhaps
> -ENODEV vs -EINVAL.

NODEV for "head doesn't exist" and INVAL for "head doesn't support
dmabuf/region/..." ?

> Are the heads guaranteed to be contiguous (the
> first -ENODEV is the end of possible heads)?

Yes, I think the valid heads should be contignous.  The guest might
still only use a non-contignous subset of the available heads though.

cheers,
  Gerd