? 2023/3/23 13:30, Xie Yongji ??:> Add eventfd for the vdpa callback so that user
> can signal it directly instead of triggering the
> callback. It will be used for vhost-vdpa case.
>
> Signed-off-by: Xie Yongji <xieyongji at bytedance.com>
Acked-by: Jason Wang <jasowang at redhat.com>
Thanks
> ---
> drivers/vhost/vdpa.c | 2 ++
> drivers/virtio/virtio_vdpa.c | 1 +
> include/linux/vdpa.h | 6 ++++++
> 3 files changed, 9 insertions(+)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index 7be9d9d8f01c..9cd878e25cff 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -599,9 +599,11 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa
*v, unsigned int cmd,
> if (vq->call_ctx.ctx) {
> cb.callback = vhost_vdpa_virtqueue_cb;
> cb.private = vq;
> + cb.trigger = vq->call_ctx.ctx;
> } else {
> cb.callback = NULL;
> cb.private = NULL;
> + cb.trigger = NULL;
> }
> ops->set_vq_cb(vdpa, idx, &cb);
> vhost_vdpa_setup_vq_irq(v, idx);
> diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
> index f3826f42b704..2a095f37f26b 100644
> --- a/drivers/virtio/virtio_vdpa.c
> +++ b/drivers/virtio/virtio_vdpa.c
> @@ -196,6 +196,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev,
unsigned int index,
> /* Setup virtqueue callback */
> cb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL;
> cb.private = info;
> + cb.trigger = NULL;
> ops->set_vq_cb(vdpa, index, &cb);
> ops->set_vq_num(vdpa, index, virtqueue_get_vring_size(vq));
>
> diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
> index e52c9a37999c..0372b2e3d38a 100644
> --- a/include/linux/vdpa.h
> +++ b/include/linux/vdpa.h
> @@ -13,10 +13,16 @@
> * struct vdpa_calllback - vDPA callback definition.
> * @callback: interrupt callback function
> * @private: the data passed to the callback function
> + * @trigger: the eventfd for the callback (Optional).
> + * When it is set, the vDPA driver must guarantee that
> + * signaling it is functional equivalent to triggering
> + * the callback. Then vDPA parent can signal it directly
> + * instead of triggering the callback.
> */
> struct vdpa_callback {
> irqreturn_t (*callback)(void *data);
> void *private;
> + struct eventfd_ctx *trigger;
> };
>
> /**