Re: [dpdk-dev] [PATCH v3 12/21] vhost: vring address setup for packed queues

[Maxime Coquelin <maxime.coquelin@redhat.com>]

On 04/05/2018 12:10 PM, Jens Freimann wrote:
> From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
> 
> Add code to set up packed queues when enabled.
> 
> Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
> Signed-off-by: Jens Freimann <jfreiman@redhat.com>
> ---
>   lib/librte_vhost/vhost.h      |  1 +
>   lib/librte_vhost/vhost_user.c | 21 ++++++++++++++++++++-
>   2 files changed, 21 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
> index 3004c26c1..20d78f883 100644
> --- a/lib/librte_vhost/vhost.h
> +++ b/lib/librte_vhost/vhost.h
> @@ -74,6 +74,7 @@ struct batch_copy_elem {
>    */
>   struct vhost_virtqueue {
>   	struct vring_desc	*desc;
> +	struct vring_desc_packed   *desc_packed;
>   	struct vring_avail	*avail;
>   	struct vring_used	*used;
>   	uint32_t		size;
> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> index 157cf2f60..183893e46 100644
> --- a/lib/librte_vhost/vhost_user.c
> +++ b/lib/librte_vhost/vhost_user.c
> @@ -469,6 +469,23 @@ translate_ring_addresses(struct virtio_net *dev, int vq_index)
>   	struct vhost_virtqueue *vq = dev->virtqueue[vq_index];
>   	struct vhost_vring_addr *addr = &vq->ring_addrs;
>   
> +	if (dev->features & (1ULL << VIRTIO_F_RING_PACKED)) {
> +		vq->desc_packed = (struct vring_desc_packed *) ring_addr_to_vva
> +			(dev, vq, addr->desc_user_addr, sizeof(vq->desc_packed));
sizeof(*vq->desc_packed)
or
sizeof(struct vring_desc_packed) for consitency.

> +		vq->desc = NULL;
> +		vq->avail = NULL;
> +		vq->used = NULL;
> +		vq->log_guest_addr = 0;
> +
> +		if (vq->last_used_idx != 0) {
> +			RTE_LOG(WARNING, VHOST_CONFIG,
> +				"last_used_idx (%u) not 0\n",
> +				vq->last_used_idx);
> +			vq->last_used_idx = 0;
> +		}
> +		return dev;
> +	}
> +
>   	/* The addresses are converted from QEMU virtual to Vhost virtual. */
>   	if (vq->desc && vq->avail && vq->used)
>   		return dev;
> @@ -481,6 +498,7 @@ translate_ring_addresses(struct virtio_net *dev, int vq_index)
>   			dev->vid);
>   		return dev;
>   	}
> +	vq->desc_packed = NULL;
>   
>   	dev = numa_realloc(dev, vq_index);
>   	vq = dev->virtqueue[vq_index];
> @@ -853,7 +871,8 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
>   static int
>   vq_is_ready(struct vhost_virtqueue *vq)
>   {
> -	return vq && vq->desc && vq->avail && vq->used &&
> +	return vq &&
> +	       (vq->desc_packed || (vq->desc && vq->avail && vq->used)) &&
>   	       vq->kickfd != VIRTIO_UNINITIALIZED_EVENTFD &&
>   	       vq->callfd != VIRTIO_UNINITIALIZED_EVENTFD;
>   }
>