On Thu, Apr 13, 2023 at 4:19 PM Alvaro Karsz <alvaro.karsz@xxxxxxxxxxxxx> wrote:
>
> Add VIRTIO_F_NOTIFICATION_DATA support for vDPA transport.
> If this feature is negotiated, the driver passes extra data when kicking
> a virtqueue.
>
> A device that offers this feature needs to implement the
> kick_vq_with_data callback.
>
> kick_vq_with_data receives the vDPA device and data.
> data includes:
> 16 bits vqn and 16 bits next available index for split virtqueues.
> 16 bits vqs, 15 least significant bits of next available index
> and 1 bit next_wrap for packed virtqueues.
>
> This patch follows a patch [1] by Viktor Prutyanov which adds support
> for the MMIO, channel I/O and modern PCI transports.
>
> Signed-off-by: Alvaro Karsz <alvaro.karsz@xxxxxxxxxxxxx>
Acked-by: Jason Wang <jasowang@xxxxxxxxxx>
Thanks
> ---
> drivers/virtio/virtio_vdpa.c | 23 +++++++++++++++++++++--
> include/linux/vdpa.h | 9 +++++++++
> 2 files changed, 30 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
> index d7f5af62dda..737c1f36d32 100644
> --- a/drivers/virtio/virtio_vdpa.c
> +++ b/drivers/virtio/virtio_vdpa.c
> @@ -112,6 +112,17 @@ static bool virtio_vdpa_notify(struct virtqueue *vq)
> return true;
> }
>
> +static bool virtio_vdpa_notify_with_data(struct virtqueue *vq)
> +{
> + struct vdpa_device *vdpa = vd_get_vdpa(vq->vdev);
> + const struct vdpa_config_ops *ops = vdpa->config;
> + u32 data = vring_notification_data(vq);
> +
> + ops->kick_vq_with_data(vdpa, data);
> +
> + return true;
> +}
> +
> static irqreturn_t virtio_vdpa_config_cb(void *private)
> {
> struct virtio_vdpa_device *vd_dev = private;
> @@ -138,6 +149,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
> struct device *dma_dev;
> const struct vdpa_config_ops *ops = vdpa->config;
> struct virtio_vdpa_vq_info *info;
> + bool (*notify)(struct virtqueue *vq) = virtio_vdpa_notify;
> struct vdpa_callback cb;
> struct virtqueue *vq;
> u64 desc_addr, driver_addr, device_addr;
> @@ -154,6 +166,14 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
> if (index >= vdpa->nvqs)
> return ERR_PTR(-ENOENT);
>
> + /* We cannot accept VIRTIO_F_NOTIFICATION_DATA without kick_vq_with_data */
> + if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA)) {
> + if (ops->kick_vq_with_data)
> + notify = virtio_vdpa_notify_with_data;
> + else
> + __virtio_clear_bit(vdev, VIRTIO_F_NOTIFICATION_DATA);
> + }
> +
> /* Queue shouldn't already be set up. */
> if (ops->get_vq_ready(vdpa, index))
> return ERR_PTR(-ENOENT);
> @@ -183,8 +203,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
> dma_dev = vdpa_get_dma_dev(vdpa);
> vq = vring_create_virtqueue_dma(index, max_num, align, vdev,
> true, may_reduce_num, ctx,
> - virtio_vdpa_notify, callback,
> - name, dma_dev);
> + notify, callback, name, dma_dev);
> if (!vq) {
> err = -ENOMEM;
> goto error_new_virtqueue;
> diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
> index 43f59ef10cc..04cdaad77dd 100644
> --- a/include/linux/vdpa.h
> +++ b/include/linux/vdpa.h
> @@ -143,6 +143,14 @@ struct vdpa_map_file {
> * @kick_vq: Kick the virtqueue
> * @vdev: vdpa device
> * @idx: virtqueue index
> + * @kick_vq_with_data: Kick the virtqueue and supply extra data
> + * (only if VIRTIO_F_NOTIFICATION_DATA is negotiated)
> + * @vdev: vdpa device
> + * @data for split virtqueue:
> + * 16 bits vqn and 16 bits next available index.
> + * @data for packed virtqueue:
> + * 16 bits vqn, 15 least significant bits of
> + * next available index and 1 bit next_wrap.
> * @set_vq_cb: Set the interrupt callback function for
> * a virtqueue
> * @vdev: vdpa device
> @@ -300,6 +308,7 @@ struct vdpa_config_ops {
> u64 device_area);
> void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);
> void (*kick_vq)(struct vdpa_device *vdev, u16 idx);
> + void (*kick_vq_with_data)(struct vdpa_device *vdev, u32 data);
> void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,
> struct vdpa_callback *cb);
> void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);
> --
> 2.34.1
>
