[v1,02/21] net/virtio: introduce notify callback for control queue

  This patch introduces a notification callback for the control
virtqueue as preliminary work to add shadow control virtqueue
support.

This new callback is required so that the shadow control queue
implemented in Virtio-user does not call the notifciation op
implemented for the driver layer.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 drivers/net/virtio/virtio_cvq.c    | 4 ++--
 drivers/net/virtio/virtio_cvq.h    | 4 ++++
 drivers/net/virtio/virtio_ethdev.c | 7 +++++++
 3 files changed, 13 insertions(+), 2 deletions(-)
  

> -----Original Message-----
> From: Maxime Coquelin <maxime.coquelin@redhat.com>
> Sent: Wednesday, November 30, 2022 11:56 PM
> To: dev@dpdk.org; Xia, Chenbo <chenbo.xia@intel.com>;
> david.marchand@redhat.com; eperezma@redhat.com
> Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
> Subject: [PATCH v1 02/21] net/virtio: introduce notify callback for
> control queue
> 
> This patch introduces a notification callback for the control
> virtqueue as preliminary work to add shadow control virtqueue
> support.
> 
> This new callback is required so that the shadow control queue
> implemented in Virtio-user does not call the notifciation op
> implemented for the driver layer.
> 
> Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> ---
>  drivers/net/virtio/virtio_cvq.c    | 4 ++--
>  drivers/net/virtio/virtio_cvq.h    | 4 ++++
>  drivers/net/virtio/virtio_ethdev.c | 7 +++++++
>  3 files changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio_cvq.c
> b/drivers/net/virtio/virtio_cvq.c
> index de4299a2a7..cd25614df8 100644
> --- a/drivers/net/virtio/virtio_cvq.c
> +++ b/drivers/net/virtio/virtio_cvq.c
> @@ -76,7 +76,7 @@ virtio_send_command_packed(struct virtnet_ctl *cvq,
>  			vq->hw->weak_barriers);
> 
>  	virtio_wmb(vq->hw->weak_barriers);
> -	virtqueue_notify(vq);
> +	cvq->notify_queue(vq, cvq->notify_cookie);
> 
>  	/* wait for used desc in virtqueue
>  	 * desc_is_used has a load-acquire or rte_io_rmb inside
> @@ -155,7 +155,7 @@ virtio_send_command_split(struct virtnet_ctl *cvq,
> 
>  	PMD_INIT_LOG(DEBUG, "vq->vq_queue_index = %d", vq->vq_queue_index);
> 
> -	virtqueue_notify(vq);
> +	cvq->notify_queue(vq, cvq->notify_cookie);
> 
>  	while (virtqueue_nused(vq) == 0)
>  		usleep(100);
> diff --git a/drivers/net/virtio/virtio_cvq.h
> b/drivers/net/virtio/virtio_cvq.h
> index 139e813ffb..224dc81422 100644
> --- a/drivers/net/virtio/virtio_cvq.h
> +++ b/drivers/net/virtio/virtio_cvq.h
> @@ -7,6 +7,8 @@
> 
>  #include <rte_ether.h>
> 
> +struct virtqueue;
> +
>  /**
>   * Control the RX mode, ie. promiscuous, allmulti, etc...
>   * All commands require an "out" sg entry containing a 1 byte
> @@ -110,6 +112,8 @@ struct virtnet_ctl {
>  	uint16_t port_id;               /**< Device port identifier. */
>  	const struct rte_memzone *mz;   /**< mem zone to populate CTL ring.
> */
>  	rte_spinlock_t lock;              /**< spinlock for control queue.
> */
> +	void (*notify_queue)(struct virtqueue *vq, void *cookie); /**<
> notify ops. */
> +	void *notify_cookie;              /**< cookie for notify ops */
>  };
> 
>  #define VIRTIO_MAX_CTRL_DATA 2048
> diff --git a/drivers/net/virtio/virtio_ethdev.c
> b/drivers/net/virtio/virtio_ethdev.c
> index d553f89a0d..8db8771f4d 100644
> --- a/drivers/net/virtio/virtio_ethdev.c
> +++ b/drivers/net/virtio/virtio_ethdev.c
> @@ -253,6 +253,12 @@ virtio_init_vring(struct virtqueue *vq)
>  	virtqueue_disable_intr(vq);
>  }
> 
> +static void
> +virtio_control_queue_notify(struct virtqueue *vq, __rte_unused void
> *cookie)
> +{
> +	virtqueue_notify(vq);
> +}
> +
>  static int
>  virtio_init_queue(struct rte_eth_dev *dev, uint16_t queue_idx)
>  {
> @@ -421,6 +427,7 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t
> queue_idx)
>  		memset(cvq->virtio_net_hdr_mz->addr, 0, rte_mem_page_size());
> 
>  		hw->cvq = cvq;
> +		vq->cq.notify_queue = &virtio_control_queue_notify;
>  	}
> 
>  	if (hw->use_va)
> --
> 2.38.1

Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>