Re: [PATCH bpf-next v4] virtio_net: add XDP meta data support

On 2020/2/5 下午5:18, Yuya Kusakabe wrote:

quoted

quoted

           case XDP_TX:
               stats->xdp_tx++;
+            xdp.data_meta = xdp.data;

Any reason for doing this?

XDP_TX can not support metadata for now, because if metasize > 0, __virtnet_xdp_xmit_one() returns EOPNOTSUPP.

static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
				   struct send_queue *sq,
				   struct xdp_frame *xdpf)
{
	struct virtio_net_hdr_mrg_rxbuf *hdr;
	int err;

	/* virtqueue want to use data area in-front of packet */
	if (unlikely(xdpf->metasize > 0))
		return -EOPNOTSUPP;

I see.

Then I think it's better to fix __virtnet_xdp_xmit_one() instead.

Thanks