Re: [PATCH v2 03/20] virtio: Add get_shm_region method

[Vivek Goyal <vgoyal@redhat.com>]

On Mon, Aug 10, 2020 at 09:47:15AM -0400, Michael S. Tsirkin wrote:
> On Fri, Aug 07, 2020 at 03:55:09PM -0400, Vivek Goyal wrote:
> > From: Sebastien Boeuf <sebastien.boeuf@intel.com>
> > 
> > Virtio defines 'shared memory regions' that provide a continuously
> > shared region between the host and guest.
> > 
> > Provide a method to find a particular region on a device.
> > 
> > Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
> > Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> > Cc: kvm@vger.kernel.org
> > Cc: "Michael S. Tsirkin" <mst@redhat.com>
> 
> I'm not sure why doesn't b4 pick up reset of this
> patchset. where can I find it?

What is b4? I think I might not have copied to right list. I cced
kvm, but probably I should sent it to virtualization@lists.linux-foundation.org
instead?

> 
> 
> IIUC all this is 5.10 material, right?

I think so. It probably is too late for 5.9.

Thanks
Vivek

> 
> 
> > ---
> >  include/linux/virtio_config.h | 17 +++++++++++++++++
> >  1 file changed, 17 insertions(+)
> > 
> > diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> > index bb4cc4910750..c859f000a751 100644
> > --- a/include/linux/virtio_config.h
> > +++ b/include/linux/virtio_config.h
> > @@ -10,6 +10,11 @@
> >  
> >  struct irq_affinity;
> >  
> > +struct virtio_shm_region {
> > +       u64 addr;
> > +       u64 len;
> > +};
> > +
> >  /**
> >   * virtio_config_ops - operations for configuring a virtio device
> >   * Note: Do not assume that a transport implements all of the operations
> > @@ -65,6 +70,7 @@ struct irq_affinity;
> >   *      the caller can then copy.
> >   * @set_vq_affinity: set the affinity for a virtqueue (optional).
> >   * @get_vq_affinity: get the affinity for a virtqueue (optional).
> > + * @get_shm_region: get a shared memory region based on the index.
> >   */
> >  typedef void vq_callback_t(struct virtqueue *);
> >  struct virtio_config_ops {
> > @@ -88,6 +94,8 @@ struct virtio_config_ops {
> >  			       const struct cpumask *cpu_mask);
> >  	const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev,
> >  			int index);
> > +	bool (*get_shm_region)(struct virtio_device *vdev,
> > +			       struct virtio_shm_region *region, u8 id);
> >  };
> >  
> >  /* If driver didn't advertise the feature, it will never appear. */
> > @@ -250,6 +258,15 @@ int virtqueue_set_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask)
> >  	return 0;
> >  }
> >  
> > +static inline
> > +bool virtio_get_shm_region(struct virtio_device *vdev,
> > +                         struct virtio_shm_region *region, u8 id)
> > +{
> > +	if (!vdev->config->get_shm_region)
> > +		return false;
> > +	return vdev->config->get_shm_region(vdev, region, id);
> > +}
> > +
> >  static inline bool virtio_is_little_endian(struct virtio_device *vdev)
> >  {
> >  	return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||
> > -- 
> > 2.25.4
>