l2tp: remove header length param from l2tp_xmit_skb

All callers pass the session structure's hdr_len field as the header
length parameter to l2tp_xmit_skb.

Since we're passing a pointer to the session structure to l2tp_xmit_skb
anyway, there's not much point breaking the header length out as a
separate argument.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/l2tp/l2tp_core.c

@@ -1017,7 +1017,7 @@ static void l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb,
 /* If caller requires the skb to have a ppp header, the header must be
  * inserted in the skb data before calling this function.
  */
-int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len)
+int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb)
 {
 	int data_len = skb->len;
 	struct l2tp_tunnel *tunnel = session->tunnel;
@@ -1035,7 +1035,7 @@ int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len
 	 * make room. Adjust truesize.
 	 */
 	headroom = NET_SKB_PAD + sizeof(struct iphdr) +
-		uhlen + hdr_len;
+		uhlen + session->hdr_len;
 	if (skb_cow_head(skb, headroom)) {
 		kfree_skb(skb);
 		return NET_XMIT_DROP;
@@ -1043,9 +1043,9 @@ int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len
 
 	/* Setup L2TP header */
 	if (tunnel->version == L2TP_HDR_VER_2)
-		l2tp_build_l2tpv2_header(session, __skb_push(skb, hdr_len));
+		l2tp_build_l2tpv2_header(session, __skb_push(skb, session->hdr_len));
 	else
-		l2tp_build_l2tpv3_header(session, __skb_push(skb, hdr_len));
+		l2tp_build_l2tpv3_header(session, __skb_push(skb, session->hdr_len));
 
 	/* Reset skb netfilter state */
 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
@@ -1079,7 +1079,7 @@ int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len
 		uh = udp_hdr(skb);
 		uh->source = inet->inet_sport;
 		uh->dest = inet->inet_dport;
-		udp_len = uhlen + hdr_len + data_len;
+		udp_len = uhlen + session->hdr_len + data_len;
 		uh->len = htons(udp_len);
 
 		/* Calculate UDP checksum if configured to do so */

net/l2tp/l2tp_core.h

@@ -261,8 +261,7 @@ int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb);
 
 /* Transmit path helpers for sending packets over the tunnel socket. */
 void l2tp_session_set_header_len(struct l2tp_session *session, int version);
-int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb,
-		  int hdr_len);
+int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb);
 
 /* Pseudowire management.
  * Pseudowires should register with l2tp core on module init, and unregister

net/l2tp/l2tp_eth.c

@@ -76,7 +76,7 @@ static netdev_tx_t l2tp_eth_dev_xmit(struct sk_buff *skb, struct net_device *dev
 	struct l2tp_eth *priv = netdev_priv(dev);
 	struct l2tp_session *session = priv->session;
 	unsigned int len = skb->len;
-	int ret = l2tp_xmit_skb(session, skb, session->hdr_len);
+	int ret = l2tp_xmit_skb(session, skb);
 
 	if (likely(ret == NET_XMIT_SUCCESS)) {
 		atomic_long_add(len, &priv->tx_bytes);

net/l2tp/l2tp_ppp.c

@@ -316,7 +316,7 @@ static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m,
 	}
 
 	local_bh_disable();
-	l2tp_xmit_skb(session, skb, session->hdr_len);
+	l2tp_xmit_skb(session, skb);
 	local_bh_enable();
 
 	sock_put(sk);
@@ -375,7 +375,7 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
 	skb->data[1] = PPP_UI;
 
 	local_bh_disable();
-	l2tp_xmit_skb(session, skb, session->hdr_len);
+	l2tp_xmit_skb(session, skb);
 	local_bh_enable();
 
 	sock_put(sk);