Re: [PATCHv4 2/2] vhost_net: a kernel-level virtio server

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Aug 26, 2009 at 03:40:59PM +0200, Arnd Bergmann wrote:
> On Tuesday 25 August 2009, Michael S. Tsirkin wrote:
> > >  I'd like to avoid that here,
> > > though it's kind of ugly.  We'd need VHOST_GET_FEATURES (and ACK) to take a
> > > struct like:
> > > 
> > >       u32 feature_size;
> > >       u32 features[];
> 
> Hmm, variable length ioctl arguments, I'd rather not go there.
> The ioctl infrastructure already has a length argument encoded
> in the ioctl number. We can use that if we need more, e.g.
> 
> /* now */
> #define VHOST_GET_FEATURES     _IOR(VHOST_VIRTIO, 0x00, __u64)
> /*
>  * uncomment if we run out of feature bits:
> 
> struct vhost_get_features2 {
> 	__u64 bits[2];
> };
> #define VHOST_GET_FEATURES2     _IOR(VHOST_VIRTIO, 0x00, \
> 			struct  vhost_get_features2)
>  */


I thought so, too. Rusty, agree?

-- 
MST