Re: [PATCH v2 10/22] iommufd/viommmu: Add IOMMUFD_CMD_VCMDQ_ALLOC ioctl

Nicolin Chen
2025-04-30T08:25:41Z

On Wed, Apr 30, 2025 at 09:52:09AM +0530, Vasant Hegde wrote:
> >>> Will the hardware replace the physical device ID in the event with
> >>> the virtual device ID when injecting the event to a guest event/PPR
> >>> queue?
> >>> If so, yea, I think you can define them separately using the> vCMDQ
> >> infrastructures:
> >>> - IOMMU_VCMDQ_TYPE_AMD_VIOMMU_CMDBUF
> >>> - IOMMU_VCMDQ_TYPE_AMD_VIOMMU_EVENTLOG
> >>> - IOMMU_VCMDQ_TYPE_AMD_VIOMMU_PPRLOG
> >>> (@Kevin @Jason Hmm, in this case we might want to revert the naming
> >>> "vCMDQ" back to "vQEUEUE", once Vasant confirms.)
> >
> > I think I should rename IOMMUFD_OBJ_VCMDQ back to IOMMUFD_OBJ_VQUEUE
> > since the same object fits three types of queue now in the AMD case.
>
> Makes sense.
>
> AMD architecture supports 5 buffers. In practice we have not implemented event
> log B / PPR Log B in Linux.
> Command buffer
> Event Log A / B
> PPR Log A / B

I think those A/B should be dual buffers of the same type?

Anyway, I have renamed all the core "vCMDQ" back to "vQUEUE" in my
local branch. Will send v3 in the next days.

Thanks
Nicolin