91f0ebf7b6
1. No need for ->ccid_init nor ->ccid_exit, this is what module_{init,exit} does and anynways neither ccid2 nor ccid3 were using it. 2. Rename struct ccid to struct ccid_operations and introduce struct ccid with a pointer to ccid_operations and rigth after it the rx or tx private state. 3. Remove the pointer to the state of the half connections from struct dccp_sock, now its derived thru ccid_priv() from the ccid pointer. Now we also can implement the setsockopt for changing the CCID easily as no ccid init routines can affect struct dccp_sock in any way that prevents other CCIDs from working if a CCID switch operation is asked by apps. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
803 lines
20 KiB
C
803 lines
20 KiB
C
/*
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* net/dccp/ccids/ccid2.c
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*
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* Copyright (c) 2005, 2006 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
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*
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* Changes to meet Linux coding standards, and DCCP infrastructure fixes.
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*
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* Copyright (c) 2006 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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/*
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* This implementation should follow: draft-ietf-dccp-ccid2-10.txt
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*
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* BUGS:
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* - sequence number wrapping
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* - jiffies wrapping
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*/
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#include <linux/config.h>
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#include "../ccid.h"
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#include "../dccp.h"
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#include "ccid2.h"
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static int ccid2_debug;
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#if 0
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#define CCID2_DEBUG
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#endif
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#ifdef CCID2_DEBUG
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#define ccid2_pr_debug(format, a...) \
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do { if (ccid2_debug) \
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printk(KERN_DEBUG "%s: " format, __FUNCTION__, ##a); \
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} while (0)
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#else
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#define ccid2_pr_debug(format, a...)
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#endif
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static const int ccid2_seq_len = 128;
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#ifdef CCID2_DEBUG
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static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx)
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{
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int len = 0;
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struct ccid2_seq *seqp;
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int pipe = 0;
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seqp = hctx->ccid2hctx_seqh;
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/* there is data in the chain */
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if (seqp != hctx->ccid2hctx_seqt) {
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seqp = seqp->ccid2s_prev;
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len++;
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if (!seqp->ccid2s_acked)
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pipe++;
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while (seqp != hctx->ccid2hctx_seqt) {
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struct ccid2_seq *prev;
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prev = seqp->ccid2s_prev;
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len++;
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if (!prev->ccid2s_acked)
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pipe++;
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/* packets are sent sequentially */
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BUG_ON(seqp->ccid2s_seq <= prev->ccid2s_seq);
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BUG_ON(seqp->ccid2s_sent < prev->ccid2s_sent);
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BUG_ON(len > ccid2_seq_len);
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seqp = prev;
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}
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}
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BUG_ON(pipe != hctx->ccid2hctx_pipe);
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ccid2_pr_debug("len of chain=%d\n", len);
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do {
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seqp = seqp->ccid2s_prev;
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len++;
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BUG_ON(len > ccid2_seq_len);
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} while(seqp != hctx->ccid2hctx_seqh);
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BUG_ON(len != ccid2_seq_len);
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ccid2_pr_debug("total len=%d\n", len);
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}
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#else
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#define ccid2_hc_tx_check_sanity(hctx) do {} while (0)
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#endif
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static int ccid2_hc_tx_send_packet(struct sock *sk,
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struct sk_buff *skb, int len)
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{
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struct ccid2_hc_tx_sock *hctx;
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switch (DCCP_SKB_CB(skb)->dccpd_type) {
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case 0: /* XXX data packets from userland come through like this */
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case DCCP_PKT_DATA:
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case DCCP_PKT_DATAACK:
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break;
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/* No congestion control on other packets */
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default:
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return 0;
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}
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hctx = ccid2_hc_tx_sk(sk);
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ccid2_pr_debug("pipe=%d cwnd=%d\n", hctx->ccid2hctx_pipe,
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hctx->ccid2hctx_cwnd);
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if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd) {
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/* OK we can send... make sure previous packet was sent off */
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if (!hctx->ccid2hctx_sendwait) {
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hctx->ccid2hctx_sendwait = 1;
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return 0;
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}
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}
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return 100; /* XXX */
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}
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static void ccid2_change_l_ack_ratio(struct sock *sk, int val)
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{
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struct dccp_sock *dp = dccp_sk(sk);
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/*
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* XXX I don't really agree with val != 2. If cwnd is 1, ack ratio
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* should be 1... it shouldn't be allowed to become 2.
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* -sorbo.
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*/
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if (val != 2) {
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struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
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int max = hctx->ccid2hctx_cwnd / 2;
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/* round up */
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if (hctx->ccid2hctx_cwnd & 1)
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max++;
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if (val > max)
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val = max;
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}
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ccid2_pr_debug("changing local ack ratio to %d\n", val);
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WARN_ON(val <= 0);
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dp->dccps_l_ack_ratio = val;
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}
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static void ccid2_change_cwnd(struct sock *sk, int val)
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{
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struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
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if (val == 0)
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val = 1;
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/* XXX do we need to change ack ratio? */
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ccid2_pr_debug("change cwnd to %d\n", val);
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BUG_ON(val < 1);
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hctx->ccid2hctx_cwnd = val;
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}
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static void ccid2_start_rto_timer(struct sock *sk);
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static void ccid2_hc_tx_rto_expire(unsigned long data)
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{
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struct sock *sk = (struct sock *)data;
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struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
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long s;
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/* XXX I don't think i'm locking correctly
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* -sorbo.
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*/
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bh_lock_sock(sk);
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if (sock_owned_by_user(sk)) {
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sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer,
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jiffies + HZ / 5);
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goto out;
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}
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ccid2_pr_debug("RTO_EXPIRE\n");
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ccid2_hc_tx_check_sanity(hctx);
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/* back-off timer */
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hctx->ccid2hctx_rto <<= 1;
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s = hctx->ccid2hctx_rto / HZ;
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if (s > 60)
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hctx->ccid2hctx_rto = 60 * HZ;
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ccid2_start_rto_timer(sk);
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/* adjust pipe, cwnd etc */
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hctx->ccid2hctx_pipe = 0;
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hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd >> 1;
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if (hctx->ccid2hctx_ssthresh < 2)
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hctx->ccid2hctx_ssthresh = 2;
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ccid2_change_cwnd(sk, 1);
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/* clear state about stuff we sent */
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hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
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hctx->ccid2hctx_ssacks = 0;
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hctx->ccid2hctx_acks = 0;
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hctx->ccid2hctx_sent = 0;
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/* clear ack ratio state. */
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hctx->ccid2hctx_arsent = 0;
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hctx->ccid2hctx_ackloss = 0;
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hctx->ccid2hctx_rpseq = 0;
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hctx->ccid2hctx_rpdupack = -1;
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ccid2_change_l_ack_ratio(sk, 1);
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ccid2_hc_tx_check_sanity(hctx);
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out:
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bh_unlock_sock(sk);
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sock_put(sk);
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}
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static void ccid2_start_rto_timer(struct sock *sk)
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{
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struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
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ccid2_pr_debug("setting RTO timeout=%ld\n", hctx->ccid2hctx_rto);
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BUG_ON(timer_pending(&hctx->ccid2hctx_rtotimer));
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sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer,
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jiffies + hctx->ccid2hctx_rto);
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}
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static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, int len)
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{
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struct dccp_sock *dp = dccp_sk(sk);
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struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
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u64 seq;
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ccid2_hc_tx_check_sanity(hctx);
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BUG_ON(!hctx->ccid2hctx_sendwait);
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hctx->ccid2hctx_sendwait = 0;
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hctx->ccid2hctx_pipe++;
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BUG_ON(hctx->ccid2hctx_pipe < 0);
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/* There is an issue. What if another packet is sent between
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* packet_send() and packet_sent(). Then the sequence number would be
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* wrong.
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* -sorbo.
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*/
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seq = dp->dccps_gss;
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hctx->ccid2hctx_seqh->ccid2s_seq = seq;
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hctx->ccid2hctx_seqh->ccid2s_acked = 0;
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hctx->ccid2hctx_seqh->ccid2s_sent = jiffies;
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hctx->ccid2hctx_seqh = hctx->ccid2hctx_seqh->ccid2s_next;
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ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->ccid2hctx_cwnd,
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hctx->ccid2hctx_pipe);
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if (hctx->ccid2hctx_seqh == hctx->ccid2hctx_seqt) {
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/* XXX allocate more space */
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WARN_ON(1);
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}
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hctx->ccid2hctx_sent++;
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/* Ack Ratio. Need to maintain a concept of how many windows we sent */
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hctx->ccid2hctx_arsent++;
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/* We had an ack loss in this window... */
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if (hctx->ccid2hctx_ackloss) {
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if (hctx->ccid2hctx_arsent >= hctx->ccid2hctx_cwnd) {
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hctx->ccid2hctx_arsent = 0;
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hctx->ccid2hctx_ackloss = 0;
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}
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}
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/* No acks lost up to now... */
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else {
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/* decrease ack ratio if enough packets were sent */
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if (dp->dccps_l_ack_ratio > 1) {
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/* XXX don't calculate denominator each time */
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int denom;
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denom = dp->dccps_l_ack_ratio * dp->dccps_l_ack_ratio -
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dp->dccps_l_ack_ratio;
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denom = hctx->ccid2hctx_cwnd * hctx->ccid2hctx_cwnd / denom;
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if (hctx->ccid2hctx_arsent >= denom) {
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ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio - 1);
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hctx->ccid2hctx_arsent = 0;
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}
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}
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/* we can't increase ack ratio further [1] */
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else {
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hctx->ccid2hctx_arsent = 0; /* or maybe set it to cwnd*/
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}
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}
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/* setup RTO timer */
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if (!timer_pending(&hctx->ccid2hctx_rtotimer)) {
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ccid2_start_rto_timer(sk);
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}
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#ifdef CCID2_DEBUG
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ccid2_pr_debug("pipe=%d\n", hctx->ccid2hctx_pipe);
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ccid2_pr_debug("Sent: seq=%llu\n", seq);
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do {
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struct ccid2_seq *seqp = hctx->ccid2hctx_seqt;
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while (seqp != hctx->ccid2hctx_seqh) {
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ccid2_pr_debug("out seq=%llu acked=%d time=%lu\n",
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seqp->ccid2s_seq, seqp->ccid2s_acked,
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seqp->ccid2s_sent);
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seqp = seqp->ccid2s_next;
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}
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} while(0);
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ccid2_pr_debug("=========\n");
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ccid2_hc_tx_check_sanity(hctx);
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#endif
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}
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/* XXX Lame code duplication!
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* returns -1 if none was found.
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* else returns the next offset to use in the function call.
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*/
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static int ccid2_ackvector(struct sock *sk, struct sk_buff *skb, int offset,
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unsigned char **vec, unsigned char *veclen)
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{
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const struct dccp_hdr *dh = dccp_hdr(skb);
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unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
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unsigned char *opt_ptr;
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const unsigned char *opt_end = (unsigned char *)dh +
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(dh->dccph_doff * 4);
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unsigned char opt, len;
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unsigned char *value;
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BUG_ON(offset < 0);
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options += offset;
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opt_ptr = options;
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if (opt_ptr >= opt_end)
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return -1;
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while (opt_ptr != opt_end) {
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opt = *opt_ptr++;
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len = 0;
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value = NULL;
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/* Check if this isn't a single byte option */
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if (opt > DCCPO_MAX_RESERVED) {
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if (opt_ptr == opt_end)
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goto out_invalid_option;
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len = *opt_ptr++;
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if (len < 3)
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goto out_invalid_option;
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/*
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* Remove the type and len fields, leaving
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* just the value size
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*/
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len -= 2;
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value = opt_ptr;
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opt_ptr += len;
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if (opt_ptr > opt_end)
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goto out_invalid_option;
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}
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switch (opt) {
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case DCCPO_ACK_VECTOR_0:
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case DCCPO_ACK_VECTOR_1:
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*vec = value;
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*veclen = len;
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return offset + (opt_ptr - options);
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break;
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}
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}
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return -1;
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out_invalid_option:
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BUG_ON(1); /* should never happen... options were previously parsed ! */
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return -1;
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}
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static void ccid2_hc_tx_kill_rto_timer(struct sock *sk)
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{
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struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
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sk_stop_timer(sk, &hctx->ccid2hctx_rtotimer);
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ccid2_pr_debug("deleted RTO timer\n");
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}
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static inline void ccid2_new_ack(struct sock *sk,
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struct ccid2_seq *seqp,
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unsigned int *maxincr)
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{
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struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
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/* slow start */
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if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh) {
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hctx->ccid2hctx_acks = 0;
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/* We can increase cwnd at most maxincr [ack_ratio/2] */
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if (*maxincr) {
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/* increase every 2 acks */
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hctx->ccid2hctx_ssacks++;
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if (hctx->ccid2hctx_ssacks == 2) {
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ccid2_change_cwnd(sk, hctx->ccid2hctx_cwnd + 1);
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hctx->ccid2hctx_ssacks = 0;
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*maxincr = *maxincr - 1;
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}
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}
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/* increased cwnd enough for this single ack */
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else {
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hctx->ccid2hctx_ssacks = 0;
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}
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}
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else {
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hctx->ccid2hctx_ssacks = 0;
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hctx->ccid2hctx_acks++;
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if (hctx->ccid2hctx_acks >= hctx->ccid2hctx_cwnd) {
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ccid2_change_cwnd(sk, hctx->ccid2hctx_cwnd + 1);
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hctx->ccid2hctx_acks = 0;
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}
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}
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/* update RTO */
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if (hctx->ccid2hctx_srtt == -1 ||
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(jiffies - hctx->ccid2hctx_lastrtt) >= hctx->ccid2hctx_srtt) {
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unsigned long r = jiffies - seqp->ccid2s_sent;
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int s;
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/* first measurement */
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if (hctx->ccid2hctx_srtt == -1) {
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ccid2_pr_debug("R: %lu Time=%lu seq=%llu\n",
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r, jiffies, seqp->ccid2s_seq);
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hctx->ccid2hctx_srtt = r;
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hctx->ccid2hctx_rttvar = r >> 1;
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}
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else {
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/* RTTVAR */
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long tmp = hctx->ccid2hctx_srtt - r;
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if (tmp < 0)
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tmp *= -1;
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tmp >>= 2;
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hctx->ccid2hctx_rttvar *= 3;
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hctx->ccid2hctx_rttvar >>= 2;
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hctx->ccid2hctx_rttvar += tmp;
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/* SRTT */
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hctx->ccid2hctx_srtt *= 7;
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hctx->ccid2hctx_srtt >>= 3;
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tmp = r >> 3;
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hctx->ccid2hctx_srtt += tmp;
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}
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s = hctx->ccid2hctx_rttvar << 2;
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/* clock granularity is 1 when based on jiffies */
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if (!s)
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s = 1;
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hctx->ccid2hctx_rto = hctx->ccid2hctx_srtt + s;
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/* must be at least a second */
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s = hctx->ccid2hctx_rto / HZ;
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/* DCCP doesn't require this [but I like it cuz my code sux] */
|
|
#if 1
|
|
if (s < 1)
|
|
hctx->ccid2hctx_rto = HZ;
|
|
#endif
|
|
/* max 60 seconds */
|
|
if (s > 60)
|
|
hctx->ccid2hctx_rto = HZ * 60;
|
|
|
|
hctx->ccid2hctx_lastrtt = jiffies;
|
|
|
|
ccid2_pr_debug("srtt: %ld rttvar: %ld rto: %ld (HZ=%d) R=%lu\n",
|
|
hctx->ccid2hctx_srtt, hctx->ccid2hctx_rttvar,
|
|
hctx->ccid2hctx_rto, HZ, r);
|
|
hctx->ccid2hctx_sent = 0;
|
|
}
|
|
|
|
/* we got a new ack, so re-start RTO timer */
|
|
ccid2_hc_tx_kill_rto_timer(sk);
|
|
ccid2_start_rto_timer(sk);
|
|
}
|
|
|
|
static void ccid2_hc_tx_dec_pipe(struct sock *sk)
|
|
{
|
|
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
|
|
|
|
hctx->ccid2hctx_pipe--;
|
|
BUG_ON(hctx->ccid2hctx_pipe < 0);
|
|
|
|
if (hctx->ccid2hctx_pipe == 0)
|
|
ccid2_hc_tx_kill_rto_timer(sk);
|
|
}
|
|
|
|
static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct dccp_sock *dp = dccp_sk(sk);
|
|
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
|
|
u64 ackno, seqno;
|
|
struct ccid2_seq *seqp;
|
|
unsigned char *vector;
|
|
unsigned char veclen;
|
|
int offset = 0;
|
|
int done = 0;
|
|
int loss = 0;
|
|
unsigned int maxincr = 0;
|
|
|
|
ccid2_hc_tx_check_sanity(hctx);
|
|
/* check reverse path congestion */
|
|
seqno = DCCP_SKB_CB(skb)->dccpd_seq;
|
|
|
|
/* XXX this whole "algorithm" is broken. Need to fix it to keep track
|
|
* of the seqnos of the dupacks so that rpseq and rpdupack are correct
|
|
* -sorbo.
|
|
*/
|
|
/* need to bootstrap */
|
|
if (hctx->ccid2hctx_rpdupack == -1) {
|
|
hctx->ccid2hctx_rpdupack = 0;
|
|
hctx->ccid2hctx_rpseq = seqno;
|
|
}
|
|
else {
|
|
/* check if packet is consecutive */
|
|
if ((hctx->ccid2hctx_rpseq + 1) == seqno) {
|
|
hctx->ccid2hctx_rpseq++;
|
|
}
|
|
/* it's a later packet */
|
|
else if (after48(seqno, hctx->ccid2hctx_rpseq)) {
|
|
hctx->ccid2hctx_rpdupack++;
|
|
|
|
/* check if we got enough dupacks */
|
|
if (hctx->ccid2hctx_rpdupack >=
|
|
hctx->ccid2hctx_numdupack) {
|
|
|
|
hctx->ccid2hctx_rpdupack = -1; /* XXX lame */
|
|
hctx->ccid2hctx_rpseq = 0;
|
|
|
|
ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio << 1);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* check forward path congestion */
|
|
/* still didn't send out new data packets */
|
|
if (hctx->ccid2hctx_seqh == hctx->ccid2hctx_seqt)
|
|
return;
|
|
|
|
switch (DCCP_SKB_CB(skb)->dccpd_type) {
|
|
case DCCP_PKT_ACK:
|
|
case DCCP_PKT_DATAACK:
|
|
break;
|
|
|
|
default:
|
|
return;
|
|
}
|
|
|
|
ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
|
|
seqp = hctx->ccid2hctx_seqh->ccid2s_prev;
|
|
|
|
/* If in slow-start, cwnd can increase at most Ack Ratio / 2 packets for
|
|
* this single ack. I round up.
|
|
* -sorbo.
|
|
*/
|
|
maxincr = dp->dccps_l_ack_ratio >> 1;
|
|
maxincr++;
|
|
|
|
/* go through all ack vectors */
|
|
while ((offset = ccid2_ackvector(sk, skb, offset,
|
|
&vector, &veclen)) != -1) {
|
|
/* go through this ack vector */
|
|
while (veclen--) {
|
|
const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
|
|
u64 ackno_end_rl;
|
|
|
|
dccp_set_seqno(&ackno_end_rl, ackno - rl);
|
|
ccid2_pr_debug("ackvec start:%llu end:%llu\n", ackno,
|
|
ackno_end_rl);
|
|
/* if the seqno we are analyzing is larger than the
|
|
* current ackno, then move towards the tail of our
|
|
* seqnos.
|
|
*/
|
|
while (after48(seqp->ccid2s_seq, ackno)) {
|
|
if (seqp == hctx->ccid2hctx_seqt) {
|
|
done = 1;
|
|
break;
|
|
}
|
|
seqp = seqp->ccid2s_prev;
|
|
}
|
|
if (done)
|
|
break;
|
|
|
|
/* check all seqnos in the range of the vector
|
|
* run length
|
|
*/
|
|
while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) {
|
|
const u8 state = (*vector &
|
|
DCCP_ACKVEC_STATE_MASK) >> 6;
|
|
|
|
/* new packet received or marked */
|
|
if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED &&
|
|
!seqp->ccid2s_acked) {
|
|
if (state ==
|
|
DCCP_ACKVEC_STATE_ECN_MARKED) {
|
|
loss = 1;
|
|
}
|
|
else {
|
|
ccid2_new_ack(sk, seqp,
|
|
&maxincr);
|
|
}
|
|
|
|
seqp->ccid2s_acked = 1;
|
|
ccid2_pr_debug("Got ack for %llu\n",
|
|
seqp->ccid2s_seq);
|
|
ccid2_hc_tx_dec_pipe(sk);
|
|
}
|
|
if (seqp == hctx->ccid2hctx_seqt) {
|
|
done = 1;
|
|
break;
|
|
}
|
|
seqp = seqp->ccid2s_next;
|
|
}
|
|
if (done)
|
|
break;
|
|
|
|
|
|
dccp_set_seqno(&ackno, ackno_end_rl - 1);
|
|
vector++;
|
|
}
|
|
if (done)
|
|
break;
|
|
}
|
|
|
|
/* The state about what is acked should be correct now
|
|
* Check for NUMDUPACK
|
|
*/
|
|
seqp = hctx->ccid2hctx_seqh->ccid2s_prev;
|
|
done = 0;
|
|
while (1) {
|
|
if (seqp->ccid2s_acked) {
|
|
done++;
|
|
if (done == hctx->ccid2hctx_numdupack) {
|
|
break;
|
|
}
|
|
}
|
|
if (seqp == hctx->ccid2hctx_seqt) {
|
|
break;
|
|
}
|
|
seqp = seqp->ccid2s_prev;
|
|
}
|
|
|
|
/* If there are at least 3 acknowledgements, anything unacknowledged
|
|
* below the last sequence number is considered lost
|
|
*/
|
|
if (done == hctx->ccid2hctx_numdupack) {
|
|
struct ccid2_seq *last_acked = seqp;
|
|
|
|
/* check for lost packets */
|
|
while (1) {
|
|
if (!seqp->ccid2s_acked) {
|
|
loss = 1;
|
|
ccid2_hc_tx_dec_pipe(sk);
|
|
}
|
|
if (seqp == hctx->ccid2hctx_seqt)
|
|
break;
|
|
seqp = seqp->ccid2s_prev;
|
|
}
|
|
|
|
hctx->ccid2hctx_seqt = last_acked;
|
|
}
|
|
|
|
/* trim acked packets in tail */
|
|
while (hctx->ccid2hctx_seqt != hctx->ccid2hctx_seqh) {
|
|
if (!hctx->ccid2hctx_seqt->ccid2s_acked)
|
|
break;
|
|
|
|
hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqt->ccid2s_next;
|
|
}
|
|
|
|
if (loss) {
|
|
/* XXX do bit shifts guarantee a 0 as the new bit? */
|
|
ccid2_change_cwnd(sk, hctx->ccid2hctx_cwnd >> 1);
|
|
hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd;
|
|
if (hctx->ccid2hctx_ssthresh < 2)
|
|
hctx->ccid2hctx_ssthresh = 2;
|
|
}
|
|
|
|
ccid2_hc_tx_check_sanity(hctx);
|
|
}
|
|
|
|
static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk)
|
|
{
|
|
struct ccid2_hc_tx_sock *hctx = ccid_priv(ccid);
|
|
int seqcount = ccid2_seq_len;
|
|
int i;
|
|
|
|
/* XXX init variables with proper values */
|
|
hctx->ccid2hctx_cwnd = 1;
|
|
hctx->ccid2hctx_ssthresh = 10;
|
|
hctx->ccid2hctx_numdupack = 3;
|
|
|
|
/* XXX init ~ to window size... */
|
|
hctx->ccid2hctx_seqbuf = kmalloc(sizeof(*hctx->ccid2hctx_seqbuf) *
|
|
seqcount, gfp_any());
|
|
if (hctx->ccid2hctx_seqbuf == NULL)
|
|
return -ENOMEM;
|
|
|
|
for (i = 0; i < (seqcount - 1); i++) {
|
|
hctx->ccid2hctx_seqbuf[i].ccid2s_next =
|
|
&hctx->ccid2hctx_seqbuf[i + 1];
|
|
hctx->ccid2hctx_seqbuf[i + 1].ccid2s_prev =
|
|
&hctx->ccid2hctx_seqbuf[i];
|
|
}
|
|
hctx->ccid2hctx_seqbuf[seqcount - 1].ccid2s_next =
|
|
hctx->ccid2hctx_seqbuf;
|
|
hctx->ccid2hctx_seqbuf->ccid2s_prev =
|
|
&hctx->ccid2hctx_seqbuf[seqcount - 1];
|
|
|
|
hctx->ccid2hctx_seqh = hctx->ccid2hctx_seqbuf;
|
|
hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
|
|
hctx->ccid2hctx_sent = 0;
|
|
hctx->ccid2hctx_rto = 3 * HZ;
|
|
hctx->ccid2hctx_srtt = -1;
|
|
hctx->ccid2hctx_rttvar = -1;
|
|
hctx->ccid2hctx_lastrtt = 0;
|
|
hctx->ccid2hctx_rpdupack = -1;
|
|
|
|
hctx->ccid2hctx_rtotimer.function = &ccid2_hc_tx_rto_expire;
|
|
hctx->ccid2hctx_rtotimer.data = (unsigned long)sk;
|
|
init_timer(&hctx->ccid2hctx_rtotimer);
|
|
|
|
ccid2_hc_tx_check_sanity(hctx);
|
|
return 0;
|
|
}
|
|
|
|
static void ccid2_hc_tx_exit(struct sock *sk)
|
|
{
|
|
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
|
|
|
|
ccid2_hc_tx_kill_rto_timer(sk);
|
|
kfree(hctx->ccid2hctx_seqbuf);
|
|
hctx->ccid2hctx_seqbuf = NULL;
|
|
}
|
|
|
|
static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
const struct dccp_sock *dp = dccp_sk(sk);
|
|
struct ccid2_hc_rx_sock *hcrx = ccid2_hc_rx_sk(sk);
|
|
|
|
switch (DCCP_SKB_CB(skb)->dccpd_type) {
|
|
case DCCP_PKT_DATA:
|
|
case DCCP_PKT_DATAACK:
|
|
hcrx->ccid2hcrx_data++;
|
|
if (hcrx->ccid2hcrx_data >= dp->dccps_r_ack_ratio) {
|
|
dccp_send_ack(sk);
|
|
hcrx->ccid2hcrx_data = 0;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
static struct ccid_operations ccid2 = {
|
|
.ccid_id = 2,
|
|
.ccid_name = "ccid2",
|
|
.ccid_owner = THIS_MODULE,
|
|
.ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock),
|
|
.ccid_hc_tx_init = ccid2_hc_tx_init,
|
|
.ccid_hc_tx_exit = ccid2_hc_tx_exit,
|
|
.ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet,
|
|
.ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent,
|
|
.ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv,
|
|
.ccid_hc_rx_obj_size = sizeof(struct ccid2_hc_rx_sock),
|
|
.ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv,
|
|
};
|
|
|
|
module_param(ccid2_debug, int, 0444);
|
|
MODULE_PARM_DESC(ccid2_debug, "Enable debug messages");
|
|
|
|
static __init int ccid2_module_init(void)
|
|
{
|
|
return ccid_register(&ccid2);
|
|
}
|
|
module_init(ccid2_module_init);
|
|
|
|
static __exit void ccid2_module_exit(void)
|
|
{
|
|
ccid_unregister(&ccid2);
|
|
}
|
|
module_exit(ccid2_module_exit);
|
|
|
|
MODULE_AUTHOR("Andrea Bittau <a.bittau@cs.ucl.ac.uk>");
|
|
MODULE_DESCRIPTION("DCCP TCP CCID2 CCID");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("net-dccp-ccid-2");
|