On Wed, 26 Apr 2017 18:12:04 +0800
"Liu, Yi L" <yi.l.liu@xxxxxxxxx> wrote:
> From: "Liu, Yi L" <yi.l.liu@xxxxxxxxxxxxxxx>
>
> This patch adds VFIO_IOMMU_TLB_INVALIDATE to propagate IOMMU TLB
> invalidate request from guest to host.
>
> In the case of SVM virtualization on VT-d, host IOMMU driver has
> no knowledge of caching structure updates unless the guest
> invalidation activities are passed down to the host. So a new
> IOCTL is needed to propagate the guest cache invalidation through
> VFIO.
>
> Signed-off-by: Liu, Yi L <yi.l.liu@xxxxxxxxxxxxxxx>
> ---
> include/uapi/linux/vfio.h | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> index 6b97987..50c51f8 100644
> --- a/include/uapi/linux/vfio.h
> +++ b/include/uapi/linux/vfio.h
> @@ -564,6 +564,15 @@ struct vfio_device_svm {
>
> #define VFIO_IOMMU_SVM_BIND_TASK _IO(VFIO_TYPE, VFIO_BASE + 22)
>
> +/* For IOMMU TLB Invalidation Propagation */
> +struct vfio_iommu_tlb_invalidate {
> + __u32 argsz;
> + __u32 length;
> + __u8 data[];
> +};
> +
> +#define VFIO_IOMMU_TLB_INVALIDATE _IO(VFIO_TYPE, VFIO_BASE + 23)
I'm kind of wondering why this isn't just a new flag bit on
vfio_device_svm, the data structure is so similar. Of course data
needs to be fully specified in uapi.
> +
> /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */
>
> /*
