virtio_net: introduce receive_small_build_xdp

Simplifying receive_small() function. Bringing the logic relating to
build_skb together.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index a0a4f35..37287ed 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -931,6 +931,34 @@ err_buf:
        return NULL;
 }
 
+static struct sk_buff *receive_small_build_skb(struct virtnet_info *vi,
+                                              unsigned int xdp_headroom,
+                                              void *buf,
+                                              unsigned int len)
+{
+       unsigned int header_offset;
+       unsigned int headroom;
+       unsigned int buflen;
+       struct sk_buff *skb;
+
+       header_offset = VIRTNET_RX_PAD + xdp_headroom;
+       headroom = vi->hdr_len + header_offset;
+       buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
+               SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+
+       skb = build_skb(buf, buflen);
+       if (!skb)
+               return NULL;
+
+       skb_reserve(skb, headroom);
+       skb_put(skb, len);
+
+       buf += header_offset;
+       memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
+
+       return skb;
+}
+
 static struct sk_buff *receive_small_xdp(struct net_device *dev,
                                         struct virtnet_info *vi,
                                         struct receive_queue *rq,
@@ -1030,9 +1058,6 @@ static struct sk_buff *receive_small(struct net_device *dev,
 {
        unsigned int xdp_headroom = (unsigned long)ctx;
        struct page *page = virt_to_head_page(buf);
-       unsigned int header_offset;
-       unsigned int headroom;
-       unsigned int buflen;
        struct sk_buff *skb;
 
        len -= vi->hdr_len;
@@ -1060,20 +1085,9 @@ static struct sk_buff *receive_small(struct net_device *dev,
                rcu_read_unlock();
        }
 
-       header_offset = VIRTNET_RX_PAD + xdp_headroom;
-       headroom = vi->hdr_len + header_offset;
-       buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
-               SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
-
-       skb = build_skb(buf, buflen);
-       if (!skb)
-               goto err;
-       skb_reserve(skb, headroom);
-       skb_put(skb, len);
-
-       buf += header_offset;
-       memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
-       return skb;
+       skb = receive_small_build_skb(vi, xdp_headroom, buf, len);
+       if (likely(skb))
+               return skb;
 
 err:
        stats->drops++;