Re: [PATCH v2 1/3] virt: acrn: Introduce interfaces for MMIO device passthrough

From: Greg KH
Date: Wed Aug 25 2021 - 16:43:38 EST


On Wed, Aug 25, 2021 at 05:01:40PM +0800, Fei Li wrote:
> From: Shuo Liu <shuo.a.liu@xxxxxxxxx>
>
> MMIO device passthrough enables an OS in a virtual machine to directly
> access a MMIO device in the host. It promises almost the native
> performance, which is required in performance-critical scenarios of
> ACRN.
>
> HSM provides the following ioctls:
> - Assign - ACRN_IOCTL_ASSIGN_MMIODEV
> Pass data struct acrn_mmiodev from userspace to the hypervisor, and
> inform the hypervisor to assign a MMIO device to a User VM.
>
> - De-assign - ACRN_IOCTL_DEASSIGN_PCIDEV
> Pass data struct acrn_mmiodev from userspace to the hypervisor, and
> inform the hypervisor to de-assign a MMIO device from a User VM.
>
> Signed-off-by: Shuo Liu <shuo.a.liu@xxxxxxxxx>
> Signed-off-by: Fei Li <fei1.li@xxxxxxxxx>

Where is the userspace code that uses this new api?

thanks,

greg k-h