net: gro: populate net/core/gro.c

Move gro code and data from net/core/dev.c to net/core/gro.c
to ease maintenance.

gro_normal_list() and gro_normal_one() are inlined
because they are called from both files.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netdevice.h

@@ -3657,6 +3657,7 @@ int netif_rx_ni(struct sk_buff *skb);
 int netif_rx_any_context(struct sk_buff *skb);
 int netif_receive_skb(struct sk_buff *skb);
 int netif_receive_skb_core(struct sk_buff *skb);
+void netif_receive_skb_list_internal(struct list_head *head);
 void netif_receive_skb_list(struct list_head *head);
 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb);
 void napi_gro_flush(struct napi_struct *napi, bool flush_old);

include/net/gro.h

@@ -416,4 +416,26 @@ static inline __wsum ip6_gro_compute_pseudo(struct sk_buff *skb, int proto)
 
 int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb);
 
+/* Pass the currently batched GRO_NORMAL SKBs up to the stack. */
+static inline void gro_normal_list(struct napi_struct *napi)
+{
+	if (!napi->rx_count)
+		return;
+	netif_receive_skb_list_internal(&napi->rx_list);
+	INIT_LIST_HEAD(&napi->rx_list);
+	napi->rx_count = 0;
+}
+
+/* Queue one GRO_NORMAL SKB up for list processing. If batch size exceeded,
+ * pass the whole batch up to the stack.
+ */
+static inline void gro_normal_one(struct napi_struct *napi, struct sk_buff *skb, int segs)
+{
+	list_add_tail(&skb->list, &napi->rx_list);
+	napi->rx_count += segs;
+	if (napi->rx_count >= gro_normal_batch)
+		gro_normal_list(napi);
+}
+
+
 #endif /* _NET_IPV6_GRO_H */