This commit does not do any functional changes. It moves xdp->data
adjustment for buffer other than first buffer to buf_to_xdp() helper so
that the xdp_buff adjustment does not scatter over different functions.

Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>
---
 drivers/net/virtio_net.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 1eb237cd5d0b..58876d1e1344 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1159,7 +1159,14 @@ static struct xdp_buff *buf_to_xdp(struct virtnet_info *vi,
 		return NULL;
 	}
 
-	xsk_buff_set_size(xdp, len);
+	if (first_buf) {
+		xsk_buff_set_size(xdp, len);
+	} else {
+		xdp_prepare_buff(xdp, xdp->data_hard_start,
+				 XDP_PACKET_HEADROOM - vi->hdr_len, len, 1);
+		xdp->flags = 0;
+	}
+
 	xsk_buff_dma_sync_for_cpu(xdp);
 
 	return xdp;
@@ -1284,7 +1291,7 @@ static int xsk_append_merge_buffer(struct virtnet_info *vi,
 			goto err;
 		}
 
-		memcpy(buf, xdp->data - vi->hdr_len, len);
+		memcpy(buf, xdp->data, len);
 
 		xsk_buff_free(xdp);
 
-- 
2.43.0

On Mon, Jun 30, 2025 at 11:13 PM Bui Quang Minh
<minhquangbui99@gmail.com> wrote:
>
> This commit does not do any functional changes. It moves xdp->data
> adjustment for buffer other than first buffer to buf_to_xdp() helper so
> that the xdp_buff adjustment does not scatter over different functions.

So I think this should go for net-next not net.

Thanks

On 7/1/25 4:23 AM, Jason Wang wrote:
> On Mon, Jun 30, 2025 at 11:13 PM Bui Quang Minh
> <minhquangbui99@gmail.com> wrote:
>>
>> This commit does not do any functional changes. It moves xdp->data
>> adjustment for buffer other than first buffer to buf_to_xdp() helper so
>> that the xdp_buff adjustment does not scatter over different functions.
> 
> So I think this should go for net-next not net.

Please, re-submit this patch only for net-next after that the first one
will land there.

Thanks,

Paolo