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

Pierre Morel
2019-02-27T10:22:48Z

On 27/02/2019 10:42, Cornelia Huck wrote:
> On Fri, 22 Feb 2019 16:29:57 +0100
> Pierre Morel <pmorel@linux.ibm.com> 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@linux.ibm.com>
>> ---
>> 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@redhat.com>
>

Thanks.
Will do the changes.

Regards,
Pierre

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