On Thu, 9 Jul 2020 08:27:51 -0600 Alex Williamson <alex.william...@redhat.com> wrote:
> > So I'm wondering can we fall back to prior proposal which only free > > one PASID for a free request. how about your opinion? > > Doesn't it still seem like it would be a useful user interface to have > a mechanism to free all pasids, by calling with exactly [0, MAX_UINT]? > I'm not sure if there's another use case for this given than the user > doesn't have strict control of the pasid values they get. Thanks, Yes, I agree free all pasids of a guest is a useful interface. Since all PASIDs under one VM is already tracked by an IOASID set with its XArray, I don't see a need to track again in VFIO. Shall we only free one & free all? IMHO, free range isn't that useful and not really symmetric to PASID allocation in that allocation is one at a time. Can we just add a new flag, e.g. VFIO_IOMMU_FREE_ALL_PASID, and ignored th range in free?