Re: [PATCH RFC v3 04/12] iommu/sva: Basic data structures for SVA

[Lu Baolu]

On 2022/4/12 14:56, Tian, Kevin wrote:
> > From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> > Sent: Sunday, April 10, 2022 6:25 PM
> >
> > Use below data structures for SVA implementation in the IOMMU core:
> >
> > - struct iommu_sva_ioas
> >    Represent the I/O address space shared with an application CPU address
> >    space. This structure has a 1:1 relationship with an mm_struct. It
> >    graps a "mm->mm_count" refcount during creation and drop it on release.
>
> s/graps/grabs

Thanks!

> > - struct iommu_domain (IOMMU_DOMAIN_SVA type)
> >    Represent a hardware pagetable that the IOMMU hardware could use for
> >    SVA translation. Multiple iommu domains could be bound with an SVA ioas
> >    and each graps a refcount from ioas in order to make sure ioas could
> >    only be freed after all domains have been unbound.
> >
> > - struct iommu_sva
> >    Represent a bond relationship between an SVA ioas and an iommu domain.
> >    If a bond already exists, it's reused and a reference is taken.
> >
> > Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
>
> btw given the actually intention of above structures does it make more
> sense to s/iommu_sva_ioas/iommu_sva/ and s/iommu_sva/iommu_sva_bond?

The use of iommu_sva has been scattered in external files as it's the
return type or parameter of the the iommu sva intefaces:

$ git grep "struct iommu_sva" :^drivers/iommu :^include/linux
drivers/dma/idxd/cdev.c:        struct iommu_sva *sva;
drivers/dma/idxd/cdev.c:        struct iommu_sva *sva;
drivers/dma/idxd/idxd.h:        struct iommu_sva *sva;
drivers/dma/idxd/init.c:        struct iommu_sva *sva;
drivers/misc/uacce/uacce.c:     struct iommu_sva *handle;

Your suggestion makes sense to me as I've also thought about it. :-)
It might be easier to arrive there through a separated cleanup series.

Best regards,
baolu