> > My general idea to complete the no-iommu feature is to add a new IOCTL > > to VFIO that is 'pin iova and return dma addr' that no-iommu userspace > > would call instead of trying to abuse mlock and /proc/ to do it. That > > ioctl would use the IOAS attached to the access just like a mdev would > > do, so it has a real IOVA, but it is not a mdev. > > This new ioctl may be IOMMUFD ioctl since its input is the IOAS and > addr, nothing related to the device. Is it? No, definately a VFIO special ioctl for VFIO no-iommu mode. > Sure. That's also why I added a noiommu test to avoid calling > unmap callback although it seems not possible to have unmap > callback as mdev drivers would implement it. Just have a special noiommu ops and use an empty unmap function and pass that to the special noiommu access creation. Jason