Re: [Qemu-devel] [RFC PATCH 5/8] VFIO: Add new IOTCL for PASID Table bind propagation

["Liu, Yi L" <yi.l.liu@linux.intel.com>]

On Wed, Apr 26, 2017 at 05:56:50PM +0100, Jean-Philippe Brucker wrote:
> On 26/04/17 11:12, Liu, Yi L wrote:
> > From: "Liu, Yi L" <yi.l.liu@linux.intel.com>
> > 
> > This patch adds VFIO_IOMMU_SVM_BIND_TASK for potential PASID table
> > binding requests.
> > 
> > On VT-d, this IOCTL cmd would be used to link the guest PASID page table
> > to host. While for other vendors, it may also be used to support other
> > kind of SVM bind request. Previously, there is a discussion on it with
> > ARM engineer. It can be found by the link below. This IOCTL cmd may
> > support SVM PASID bind request from userspace driver, or page table(cr3)
> > bind request from guest. These SVM bind requests would be supported by
> > adding different flags. e.g. VFIO_SVM_BIND_PASID is added to support
> > PASID bind from userspace driver, VFIO_SVM_BIND_PGTABLE is added to
> > support page table bind from guest.
> > 
> > https://patchwork.kernel.org/patch/9594231/
> > 
> > Signed-off-by: Liu, Yi L <yi.l.liu@linux.intel.com>
> > ---
> >  include/uapi/linux/vfio.h | 17 +++++++++++++++++
> >  1 file changed, 17 insertions(+)
> > 
> > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> > index 519eff3..6b97987 100644
> > --- a/include/uapi/linux/vfio.h
> > +++ b/include/uapi/linux/vfio.h
> > @@ -547,6 +547,23 @@ struct vfio_iommu_type1_dma_unmap {
> >  #define VFIO_IOMMU_ENABLE	_IO(VFIO_TYPE, VFIO_BASE + 15)
> >  #define VFIO_IOMMU_DISABLE	_IO(VFIO_TYPE, VFIO_BASE + 16)
> >  
> > +/* IOCTL for Shared Virtual Memory Bind */
> > +struct vfio_device_svm {
> > +	__u32	argsz;
> > +#define VFIO_SVM_BIND_PASIDTBL	(1 << 0) /* Bind PASID Table */
> > +#define VFIO_SVM_BIND_PASID	(1 << 1) /* Bind PASID from userspace driver */
> > +#define VFIO_SVM_BIND_PGTABLE	(1 << 2) /* Bind guest mmu page table */
> > +	__u32	flags;
> > +	__u32	length;
> > +	__u8	data[];
> > +};
> > +
> > +#define VFIO_SVM_TYPE_MASK	(VFIO_SVM_BIND_PASIDTBL | \
> > +				VFIO_SVM_BIND_PASID | \
> > +				VFIO_SVM_BIND_PGTABLE)
> > +
> > +#define VFIO_IOMMU_SVM_BIND_TASK	_IO(VFIO_TYPE, VFIO_BASE + 22)
> 
> This could be called "VFIO_IOMMU_SVM_BIND, since it will be used both to
> bind tables and individual tasks.

yes, it is. would modify it in next version.

Thanks,
Yi L 
> Thanks,
> Jean
>