Re: [PATCH v4 2/9] vfio-iommufd: Create iommufd_access for noiommu devices

Jason Gunthorpe
2023-04-28T12:08:21Z

On Fri, Apr 28, 2023 at 02:21:26PM +0800, Yi Liu wrote:

> but this patch needs to use vfio_iommufd_emulated_bind() and
> vfio_iommufd_emulated_unbind() for the noiommu devices when binding
> to iommufd. So needs to check noiommu in the vfio_iommufd_bind()
> and vfio_iommu_unbind() as well.

I'm not sure this is strictly necessary, it just needs an access

The emulated stuff is for mdev only, it should not be confused with
no-iommu

Eg if you had a no_iommu_access value to store the access it would be
fine and could serve as the 'this is no_iommu' flag

The only purpose of the access at this moment is to get an iommufdctx
id to return to userspace.

Jason