[DCCP] CCID2: Initial CCID2 (TCP-Like) implementation

Original work by Andrea Bittau, Arnaldo Melo cleaned up and fixed several
issues on the merge process.

For now CCID2 was turned the default for all SOCK_DCCP connections, but this
will be remedied soon with the merge of the feature negotiation code.

Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dccp/ccids/ccid2.h b/net/dccp/ccids/ccid2.h
new file mode 100644
index 0000000..0b08c90
--- /dev/null
+++ b/net/dccp/ccids/ccid2.h
@@ -0,0 +1,69 @@
+/*
+ *  net/dccp/ccids/ccid2.h
+ *
+ *  Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#ifndef _DCCP_CCID2_H_
+#define _DCCP_CCID2_H_
+
+struct ccid2_seq {
+	u64			ccid2s_seq;
+	unsigned long		ccid2s_sent;
+	int			ccid2s_acked;
+	struct ccid2_seq	*ccid2s_prev;
+	struct ccid2_seq	*ccid2s_next;
+};
+
+/** struct ccid2_hc_tx_sock - CCID2 TX half connection
+ *
+ * @ccid2hctx_ssacks - ACKs recv in slow start
+ * @ccid2hctx_acks - ACKS recv in AI phase
+ * @ccid2hctx_sent - packets sent in this window
+ * @ccid2hctx_lastrtt -time RTT was last measured
+ * @ccid2hctx_arsent - packets sent [ack ratio]
+ * @ccid2hctx_ackloss - ack was lost in this win
+ * @ccid2hctx_rpseq - last consecutive seqno
+ * @ccid2hctx_rpdupack - dupacks since rpseq
+*/
+struct ccid2_hc_tx_sock {
+	int			ccid2hctx_cwnd;
+	int			ccid2hctx_ssacks;
+	int			ccid2hctx_acks;
+	int			ccid2hctx_ssthresh;
+	int			ccid2hctx_pipe;
+	int			ccid2hctx_numdupack;
+	struct ccid2_seq	*ccid2hctx_seqbuf;
+	struct ccid2_seq	*ccid2hctx_seqh;
+	struct ccid2_seq	*ccid2hctx_seqt;
+	long			ccid2hctx_rto;
+	long			ccid2hctx_srtt;
+	long			ccid2hctx_rttvar;
+	int			ccid2hctx_sent;
+	unsigned long		ccid2hctx_lastrtt;
+	struct timer_list	ccid2hctx_rtotimer;
+	unsigned long		ccid2hctx_arsent;
+	int			ccid2hctx_ackloss;
+	u64			ccid2hctx_rpseq;
+	int			ccid2hctx_rpdupack;
+	int			ccid2hctx_sendwait;
+};
+
+struct ccid2_hc_rx_sock {
+	int	ccid2hcrx_data;
+};
+
+#endif /* _DCCP_CCID2_H_ */