On 2020/4/30 下午7:22, Jesper Dangaard Brouer wrote:
In vhost_net_build_xdp() the 'buf' that gets queued via an xdp_buff
have embedded a struct tun_xdp_hdr (located at xdp->data_hard_start)
which contains the buffer length 'buflen' (with tailroom for
skb_shared_info). Also storing this buflen in xdp->frame_sz, does not
obsolete struct tun_xdp_hdr, as it also contains a struct
virtio_net_hdr with other information.
Cc: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
---
drivers/vhost/net.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 2927f02cc7e1..516519dcc8ff 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -747,6 +747,7 @@ static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
xdp->data = buf + pad;
xdp->data_end = xdp->data + len;
hdr->buflen = buflen;
+ xdp->frame_sz = buflen;
--net->refcnt_bias;
alloc_frag->offset += buflen;
Hi Jesper:
As I said in v1, tun will do this for us (patch 19) via hdr->buflen. So
it looks to me this is not necessary?
Thanks
