Re: [PATCH v1 08/16] iommufd/viommu: Add IOMMU_VIOMMU_INVALIDATE ioctl

Nicolin Chen
2024-08-15T23:52:02Z

On Thu, Aug 15, 2024 at 08:24:05PM -0300, Jason Gunthorpe wrote:
> On Wed, Aug 07, 2024 at 01:10:49PM -0700, Nicolin Chen wrote:
> > @@ -946,4 +947,40 @@ struct iommu_viommu_unset_vdev_id {
> > __aligned_u64 vdev_id;
> > };
> > #define IOMMU_VIOMMU_UNSET_VDEV_ID _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VIOMMU_UNSET_VDEV_ID)
> > +
> > +/**
> > + * enum iommu_viommu_invalidate_data_type - VIOMMU Cache Invalidate Data Type
> > + * @IOMMU_VIOMMU_INVALIDATE_DATA_ARM_SMMUV3: Invalidation data for ARM SMMUv3
> > + */
> > +enum iommu_viommu_invalidate_data_type {
> > + IOMMU_VIOMMU_INVALIDATE_DATA_ARM_SMMUV3,
> > +};
>
> =1 here I think. Lets try to avoid 0 for the types..
>
> And this shouldn't be in this patch
>
> But also we can probably just use reuse enum iommu_hwpt_invalidate_data_type
> here?

Would that force IOMMU drivers to implement both hwpt and viommu
invalidations? SMMUv3 driver would implement both anyway though..

> > +struct iommu_viommu_invalidate {
> > + __u32 size;
> > + __u32 viommu_id;
> > + __aligned_u64 data_uptr;
> > + __u32 data_type;
> > + __u32 entry_len;
> > + __u32 entry_num;
> > + __u32 __reserved;
> > +};
> > +#define IOMMU_VIOMMU_INVALIDATE _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VIOMMU_INVALIDATE)
>
> I wonder if we should use IOMMU_HWPT_INVALIDATE? the hwpt_id can tell
> which mode it is in. The ioctl becomes badly named but these have
> identical arguments.

Mostly they would be identical. So, I think that's doable.

If someday we need something hwpt-specific or viommu-specific, we
can always duplicate a different structure.

Thanks
Nicolin