Re: [PATCH v6 1/4] vdpa: Add suspend operation

[Eugenio Perez Martin]

On Wed, Jun 29, 2022 at 6:10 AM Jason Wang <jasowang@xxxxxxxxxx> wrote:
>
> On Fri, Jun 24, 2022 at 12:07 AM Eugenio Pérez <eperezma@xxxxxxxxxx> wrote:
> >
> > This operation is optional: It it's not implemented, backend feature bit
> > will not be exposed.
>
> A question, do we allow suspending a device without DRIVER_OK?
>

That should be invalid. In particular, vdpa_sim will resume in that
case, but I guess it would depend on the device.

Do you think it should be controlled in the vdpa frontend code?

Thanks!

> Thanks
>
> >
> > Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
> > ---
> >  include/linux/vdpa.h | 4 ++++
> >  1 file changed, 4 insertions(+)
> >
> > diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
> > index 7b4a13d3bd91..d282f464d2f1 100644
> > --- a/include/linux/vdpa.h
> > +++ b/include/linux/vdpa.h
> > @@ -218,6 +218,9 @@ struct vdpa_map_file {
> >   * @reset:                     Reset device
> >   *                             @vdev: vdpa device
> >   *                             Returns integer: success (0) or error (< 0)
> > + * @suspend:                   Suspend or resume the device (optional)
> > + *                             @vdev: vdpa device
> > + *                             Returns integer: success (0) or error (< 0)
> >   * @get_config_size:           Get the size of the configuration space includes
> >   *                             fields that are conditional on feature bits.
> >   *                             @vdev: vdpa device
> > @@ -319,6 +322,7 @@ struct vdpa_config_ops {
> >         u8 (*get_status)(struct vdpa_device *vdev);
> >         void (*set_status)(struct vdpa_device *vdev, u8 status);
> >         int (*reset)(struct vdpa_device *vdev);
> > +       int (*suspend)(struct vdpa_device *vdev);
> >         size_t (*get_config_size)(struct vdpa_device *vdev);
> >         void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
> >                            void *buf, unsigned int len);
> > --
> > 2.31.1
> >
>