Re: [PATCH RFC v1 08/15] iommu: Add asid_bits to arm smmu-v3 stage1 table info

[Vivek Kumar Gautam]

On 3/3/21 10:48 PM, Jean-Philippe Brucker wrote:
> On Fri, Jan 15, 2021 at 05:43:35PM +0530, Vivek Gautam wrote:
> > aisd_bits data is required to prepare stage-1 tables for arm-smmu-v3.
> >
> > Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxx>
> > Cc: Joerg Roedel <joro@xxxxxxxxxx>
> > Cc: Will Deacon <will.deacon@xxxxxxx>
> > Cc: Robin Murphy <robin.murphy@xxxxxxx>
> > Cc: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
> > Cc: Eric Auger <eric.auger@xxxxxxxxxx>
> > Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
> > Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
> > Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> > Cc: Liu Yi L <yi.l.liu@xxxxxxxxx>
> > Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
> > Cc: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@xxxxxxxxxx>
> > ---
> >   include/uapi/linux/iommu.h | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h
> > index 082d758dd016..96abbfc7c643 100644
> > --- a/include/uapi/linux/iommu.h
> > +++ b/include/uapi/linux/iommu.h
> > @@ -357,7 +357,7 @@ struct iommu_pasid_smmuv3 {
> >   	__u32	version;
> >   	__u8	s1fmt;
> >   	__u8	s1dss;
> > -	__u8	padding[2];
> > +	__u16	asid_bits;
>
> Is this used anywhere?  This struct is passed from host userspace to host
> kernel to attach the PASID table, so I don't think it needs an asid_bits
> field.

Yea, must have missed removing it from the WIP work. Will remove it.

Thanks
Vivek