Re: [PATCH v4 4/7] vfio: ap: register IOMMU VFIO notifier

[Pierre Morel]

On 27/02/2019 10:42, Cornelia Huck wrote:
> On Fri, 22 Feb 2019 16:29:57 +0100
> Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
>
> > To be able to use the VFIO interface to facilitate the
> > mediated device memory pining/unpining we need to register
>
> s/pining/pinning/ (unless it's pining for the fjords :)
>
> > a notifier for IOMMU.
> >
> > Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> > ---
> >   drivers/s390/crypto/vfio_ap_ops.c     | 53 ++++++++++++++++++++++++++++++++---
> >   drivers/s390/crypto/vfio_ap_private.h |  2 ++
> >   2 files changed, 51 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> > index 172d6eb..1b5130a 100644
> > --- a/drivers/s390/crypto/vfio_ap_ops.c
> > +++ b/drivers/s390/crypto/vfio_ap_ops.c
> > @@ -748,6 +748,36 @@ static const struct attribute_group *vfio_ap_mdev_attr_groups[] = {
> >   };
> >   
> >   /**
> > + * vfio_ap_mdev_iommu_notifier: IOMMU notifier callback
> > + *
> > + * @nb: The notifier block
> > + * @action: Action to be taken (VFIO_IOMMU_NOTIFY_DMA_UNMAP)
>
> I'd drop this annotation; you only do something for UNMAP but nothing
> prevents the caller from passing in something else :)
>
> > + * @data: the specific unmap structure for vfio_iommu_type1
>
> "data associated with the request" ?
>
> (same reasoning as above)
>
> > + *
> > + * Unpins the guest IOVA. (The NIB guest address we pinned before).
> > + * Return NOTIFY_OK after unpining on a UNMAP request.
> > + * otherwise, returns NOTIFY_DONE .
>
> "For an UNMAP request, unpin the guest IOVA (the NIB guest address we
> pinned before). Other requests are ignored."
>
> ?
>
> > + */
>
> Looks sane to me.
>
> With comments changed,
> Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>

Thanks.
Will do the changes.

Regards,
Pierre

--
Pierre Morel
Linux/KVM/QEMU in BÃblingen - Germany