sctp: fasthandoff with ASCONF at mobile-node

Fast retransmission after changing the last address
with ASCONF negotiation

Signed-off-by: Michio Honda <micchie@sfc.wide.ad.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 0 deletions

diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index 394c57c..3889330 100644
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -641,3 +641,19 @@ void sctp_transport_reset(struct sctp_transport *t)
 	t->cacc.next_tsn_at_change = 0;
 	t->cacc.cacc_saw_newack = 0;
 }
+
+/* Schedule retransmission on the given transport */
+void sctp_transport_immediate_rtx(struct sctp_transport *t)
+{
+	/* Stop pending T3_rtx_timer */
+	if (timer_pending(&t->T3_rtx_timer)) {
+		(void)del_timer(&t->T3_rtx_timer);
+		sctp_transport_put(t);
+	}
+	sctp_retransmit(&t->asoc->outqueue, t, SCTP_RTXR_T3_RTX);
+	if (!timer_pending(&t->T3_rtx_timer)) {
+		if (!mod_timer(&t->T3_rtx_timer, jiffies + t->rto))
+			sctp_transport_hold(t);
+	}
+	return;
+}