[PATCH v3 7/8] vhost: vDPA blk device gets ready when any queue is ready

[Xia, Chenbo]

> -----Original Message-----
> From: Pei, Andy <andy.pei at intel.com>
> Sent: Friday, September 16, 2022 2:16 PM
> To: dev at dpdk.org
> Cc: Xia, Chenbo <chenbo.xia at intel.com>; Xu, Rosen <rosen.xu at intel.com>;
> Huang, Wei <wei.huang at intel.com>; Cao, Gang <gang.cao at intel.com>;
> maxime.coquelin at redhat.com
> Subject: [PATCH v3 7/8] vhost: vDPA blk device gets ready when any queue
> is ready
> 
> When boot from virtio blk device, seabios in QEMU only enables one queue.
> To work in this scenario, vDPA BLK device back-end conf_dev when any

What is conf_dev?

> queue is ready.
> 
> Signed-off-by: Andy Pei <andy.pei at intel.com>
> Signed-off-by: Huang Wei <wei.huang at intel.com>
> ---
>  lib/vhost/vhost_user.c | 51 ++++++++++++++++++++++++++++++++-------------
> -----
>  1 file changed, 33 insertions(+), 18 deletions(-)
> 
> diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c
> index 4ad28ba..9169cf5 100644
> --- a/lib/vhost/vhost_user.c
> +++ b/lib/vhost/vhost_user.c
> @@ -1449,9 +1449,10 @@
>  }
> 
>  #define VIRTIO_BUILTIN_NUM_VQS_TO_BE_READY 2u
> +#define VIRTIO_BLK_NUM_VQS_TO_BE_READY 1u
> 
>  static int
> -virtio_is_ready(struct virtio_net *dev)
> +virtio_is_ready(struct virtio_net *dev, uint32_t vdpa_type)
>  {
>  	struct vhost_virtqueue *vq;
>  	uint32_t i, nr_vring = dev->nr_vring;
> @@ -1462,13 +1463,20 @@
>  	if (!dev->nr_vring)
>  		return 0;
> 
> -	if (dev->flags & VIRTIO_DEV_BUILTIN_VIRTIO_NET) {
> -		nr_vring = VIRTIO_BUILTIN_NUM_VQS_TO_BE_READY;
> -
> -		if (dev->nr_vring < nr_vring)
> -			return 0;
> +	if (vdpa_type == RTE_VHOST_VDPA_DEVICE_TYPE_NET) {
> +		if (dev->flags & VIRTIO_DEV_BUILTIN_VIRTIO_NET)
> +			nr_vring = VIRTIO_BUILTIN_NUM_VQS_TO_BE_READY;
> +	} else {
> +		/*
> +		 * vdpa_type == RTE_VHOST_VDPA_DEVICE_TYPE_BLK
> +		 * is the only case currently
> +		 */
> +		nr_vring = VIRTIO_BLK_NUM_VQS_TO_BE_READY;

You should consider the case when vdpa device is not there. Maybe you can
use int for vdpa_type, -1 for non-vdpa.

Also note that below check is only needed for some cases.

Thanks,
Chenbo

>  	}
> 
> +	if (dev->nr_vring < nr_vring)
> +		return 0;
> +
>  	for (i = 0; i < nr_vring; i++) {
>  		vq = dev->virtqueue[i];
> 
> @@ -3167,7 +3175,25 @@ static int is_vring_iotlb(struct virtio_net *dev,
>  	if (unlock_required)
>  		vhost_user_unlock_all_queue_pairs(dev);
> 
> -	if (ret != 0 || !virtio_is_ready(dev))
> +	if (ret != 0)
> +		goto out;
> +
> +	vdpa_dev = dev->vdpa_dev;
> +	if (vdpa_dev) {
> +		if (vdpa_dev->ops->get_dev_type) {
> +			ret = vdpa_dev->ops->get_dev_type(vdpa_dev, &vdpa_type);
> +			if (ret) {
> +				VHOST_LOG_CONFIG(dev->ifname, ERR,
> +					"failed to get vdpa dev type.\n");
> +				ret = -1;
> +				goto out;
> +			}
> +		} else {
> +			vdpa_type = RTE_VHOST_VDPA_DEVICE_TYPE_NET;
> +		}
> +	}
> +
> +	if (!virtio_is_ready(dev, vdpa_type))
>  		goto out;
> 
>  	/*
> @@ -3181,20 +3207,9 @@ static int is_vring_iotlb(struct virtio_net *dev,
>  			dev->flags |= VIRTIO_DEV_RUNNING;
>  	}
> 
> -	vdpa_dev = dev->vdpa_dev;
>  	if (!vdpa_dev)
>  		goto out;
> 
> -	if (vdpa_dev->ops->get_dev_type) {
> -		ret = vdpa_dev->ops->get_dev_type(vdpa_dev, &vdpa_type);
> -		if (ret) {
> -			VHOST_LOG_CONFIG(dev->ifname, ERR, "failed to get vdpa
> dev type.\n");
> -			ret = -1;
> -			goto out;
> -		}
> -	} else {
> -		vdpa_type = RTE_VHOST_VDPA_DEVICE_TYPE_NET;
> -	}
>  	if (vdpa_type == RTE_VHOST_VDPA_DEVICE_TYPE_BLK
>  		&& request != VHOST_USER_SET_VRING_CALL)
>  		goto out;
> --
> 1.8.3.1