l2tp: do data sequence number handling in a separate func
This change moves some code handling data sequence numbers into a
separate function to avoid too much indentation. This is to prepare
for some changes to data sequence number handling in subsequent
patches.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
index 6984c3a..5ca2965 100644
--- a/net/l2tp/l2tp_core.c
+++ b/net/l2tp/l2tp_core.c
@@ -542,6 +542,38 @@
return __skb_checksum_complete(skb);
}
+/* If packet has sequence numbers, queue it if acceptable. Returns 0 if
+ * acceptable, else non-zero.
+ */
+static int l2tp_recv_data_seq(struct l2tp_session *session, struct sk_buff *skb)
+{
+ if (session->reorder_timeout != 0) {
+ /* Packet reordering enabled. Add skb to session's
+ * reorder queue, in order of ns.
+ */
+ l2tp_recv_queue_skb(session, skb);
+ } else {
+ /* Packet reordering disabled. Discard out-of-sequence
+ * packets
+ */
+ if (L2TP_SKB_CB(skb)->ns != session->nr) {
+ atomic_long_inc(&session->stats.rx_seq_discards);
+ l2tp_dbg(session, L2TP_MSG_SEQ,
+ "%s: oos pkt %u len %d discarded, waiting for %u, reorder_q_len=%d\n",
+ session->name, L2TP_SKB_CB(skb)->ns,
+ L2TP_SKB_CB(skb)->length, session->nr,
+ skb_queue_len(&session->reorder_q));
+ goto discard;
+ }
+ skb_queue_tail(&session->reorder_q, skb);
+ }
+
+ return 0;
+
+discard:
+ return 1;
+}
+
/* Do receive processing of L2TP data frames. We handle both L2TPv2
* and L2TPv3 data frames here.
*
@@ -757,26 +789,8 @@
* enabled. Saved L2TP protocol info is stored in skb->sb[].
*/
if (L2TP_SKB_CB(skb)->has_seq) {
- if (session->reorder_timeout != 0) {
- /* Packet reordering enabled. Add skb to session's
- * reorder queue, in order of ns.
- */
- l2tp_recv_queue_skb(session, skb);
- } else {
- /* Packet reordering disabled. Discard out-of-sequence
- * packets
- */
- if (L2TP_SKB_CB(skb)->ns != session->nr) {
- atomic_long_inc(&session->stats.rx_seq_discards);
- l2tp_dbg(session, L2TP_MSG_SEQ,
- "%s: oos pkt %u len %d discarded, waiting for %u, reorder_q_len=%d\n",
- session->name, L2TP_SKB_CB(skb)->ns,
- L2TP_SKB_CB(skb)->length, session->nr,
- skb_queue_len(&session->reorder_q));
- goto discard;
- }
- skb_queue_tail(&session->reorder_q, skb);
- }
+ if (l2tp_recv_data_seq(session, skb))
+ goto discard;
} else {
/* No sequence numbers. Add the skb to the tail of the
* reorder queue. This ensures that it will be