Re: [PATCHv4] xen/gntdev: add ioctl for grant copy

[David Vrabel <david.vrabel@citrix.com>]

On 01/12/15 16:43, David Vrabel wrote:
> Add IOCTL_GNTDEV_GRANT_COPY to allow applications to copy between user
> space buffers and grant references.
> 
> This interface is similar to the GNTTABOP_copy hypercall ABI except
> the local buffers are provided using a virtual address (instead of a
> GFN and offset).  To avoid userspace from having to page align its
> buffers the driver will use two or more ops if required.
> 
> If the ioctl returns 0, the application must check the status of each
> segment with the segments status field.  If the ioctl returns a -ve
> error code (EINVAL or EFAULT), the status of individual ops is
> undefined.

Konrad, Boris,  any comments?

David