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-rw-r--r--net/dccp/ccids/ccid3.c1221
1 files changed, 1221 insertions, 0 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
new file mode 100644
index 000000000000..7bf3b3a91e97
--- /dev/null
+++ b/net/dccp/ccids/ccid3.c
@@ -0,0 +1,1221 @@
+/*
+ * net/dccp/ccids/ccid3.c
+ *
+ * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
+ * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz>
+ *
+ * An implementation of the DCCP protocol
+ *
+ * This code has been developed by the University of Waikato WAND
+ * research group. For further information please see http://www.wand.net.nz/
+ *
+ * This code also uses code from Lulea University, rereleased as GPL by its
+ * authors:
+ * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
+ *
+ * Changes to meet Linux coding standards, to make it meet latest ccid3 draft
+ * and to make it work as a loadable module in the DCCP stack written by
+ * Arnaldo Carvalho de Melo <acme@conectiva.com.br>.
+ *
+ * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *
+ * 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.
+ */
+
+#include <linux/config.h>
+#include "../ccid.h"
+#include "../dccp.h"
+#include "lib/packet_history.h"
+#include "lib/loss_interval.h"
+#include "lib/tfrc.h"
+#include "ccid3.h"
+
+/*
+ * Reason for maths with 10 here is to avoid 32 bit overflow when a is big.
+ */
+static inline u32 usecs_div(const u32 a, const u32 b)
+{
+ const u32 tmp = a * (USEC_PER_SEC / 10);
+ return b > 20 ? tmp / (b / 10) : tmp;
+}
+
+static int ccid3_debug;
+
+#ifdef CCID3_DEBUG
+#define ccid3_pr_debug(format, a...) \
+ do { if (ccid3_debug) \
+ printk(KERN_DEBUG "%s: " format, __FUNCTION__, ##a); \
+ } while (0)
+#else
+#define ccid3_pr_debug(format, a...)
+#endif
+
+static struct dccp_tx_hist *ccid3_tx_hist;
+static struct dccp_rx_hist *ccid3_rx_hist;
+static struct dccp_li_hist *ccid3_li_hist;
+
+static int ccid3_init(struct sock *sk)
+{
+ ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
+ return 0;
+}
+
+static void ccid3_exit(struct sock *sk)
+{
+ ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
+}
+
+/* TFRC sender states */
+enum ccid3_hc_tx_states {
+ TFRC_SSTATE_NO_SENT = 1,
+ TFRC_SSTATE_NO_FBACK,
+ TFRC_SSTATE_FBACK,
+ TFRC_SSTATE_TERM,
+};
+
+#ifdef CCID3_DEBUG
+static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state)
+{
+ static char *ccid3_state_names[] = {
+ [TFRC_SSTATE_NO_SENT] = "NO_SENT",
+ [TFRC_SSTATE_NO_FBACK] = "NO_FBACK",
+ [TFRC_SSTATE_FBACK] = "FBACK",
+ [TFRC_SSTATE_TERM] = "TERM",
+ };
+
+ return ccid3_state_names[state];
+}
+#endif
+
+static inline void ccid3_hc_tx_set_state(struct sock *sk,
+ enum ccid3_hc_tx_states state)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+ enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state;
+
+ ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
+ dccp_role(sk), sk, ccid3_tx_state_name(oldstate),
+ ccid3_tx_state_name(state));
+ WARN_ON(state == oldstate);
+ hctx->ccid3hctx_state = state;
+}
+
+/* Calculate new t_ipi (inter packet interval) by t_ipi = s / X_inst */
+static inline void ccid3_calc_new_t_ipi(struct ccid3_hc_tx_sock *hctx)
+{
+ /*
+ * If no feedback spec says t_ipi is 1 second (set elsewhere and then
+ * doubles after every no feedback timer (separate function)
+ */
+ if (hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK)
+ hctx->ccid3hctx_t_ipi = usecs_div(hctx->ccid3hctx_s,
+ hctx->ccid3hctx_x);
+}
+
+/* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */
+static inline void ccid3_calc_new_delta(struct ccid3_hc_tx_sock *hctx)
+{
+ hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2,
+ TFRC_OPSYS_HALF_TIME_GRAN);
+}
+
+/*
+ * Update X by
+ * If (p > 0)
+ * x_calc = calcX(s, R, p);
+ * X = max(min(X_calc, 2 * X_recv), s / t_mbi);
+ * Else
+ * If (now - tld >= R)
+ * X = max(min(2 * X, 2 * X_recv), s / R);
+ * tld = now;
+ */
+static void ccid3_hc_tx_update_x(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+
+ /* To avoid large error in calcX */
+ if (hctx->ccid3hctx_p >= TFRC_SMALLEST_P) {
+ hctx->ccid3hctx_x_calc = tfrc_calc_x(hctx->ccid3hctx_s,
+ hctx->ccid3hctx_rtt,
+ hctx->ccid3hctx_p);
+ hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_calc,
+ 2 * hctx->ccid3hctx_x_recv),
+ (hctx->ccid3hctx_s /
+ TFRC_MAX_BACK_OFF_TIME));
+ } else {
+ struct timeval now;
+
+ do_gettimeofday(&now);
+ if (timeval_delta(&now, &hctx->ccid3hctx_t_ld) >=
+ hctx->ccid3hctx_rtt) {
+ hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_recv,
+ hctx->ccid3hctx_x) * 2,
+ usecs_div(hctx->ccid3hctx_s,
+ hctx->ccid3hctx_rtt));
+ hctx->ccid3hctx_t_ld = now;
+ }
+ }
+}
+
+static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
+{
+ struct sock *sk = (struct sock *)data;
+ struct dccp_sock *dp = dccp_sk(sk);
+ unsigned long next_tmout = 0;
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+
+ bh_lock_sock(sk);
+ if (sock_owned_by_user(sk)) {
+ /* Try again later. */
+ /* XXX: set some sensible MIB */
+ sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
+ jiffies + HZ / 5);
+ goto out;
+ }
+
+ ccid3_pr_debug("%s, sk=%p, state=%s\n", dccp_role(sk), sk,
+ ccid3_tx_state_name(hctx->ccid3hctx_state));
+
+ switch (hctx->ccid3hctx_state) {
+ case TFRC_SSTATE_TERM:
+ goto out;
+ case TFRC_SSTATE_NO_FBACK:
+ /* Halve send rate */
+ hctx->ccid3hctx_x /= 2;
+ if (hctx->ccid3hctx_x < (hctx->ccid3hctx_s /
+ TFRC_MAX_BACK_OFF_TIME))
+ hctx->ccid3hctx_x = (hctx->ccid3hctx_s /
+ TFRC_MAX_BACK_OFF_TIME);
+
+ ccid3_pr_debug("%s, sk=%p, state=%s, updated tx rate to %d "
+ "bytes/s\n",
+ dccp_role(sk), sk,
+ ccid3_tx_state_name(hctx->ccid3hctx_state),
+ hctx->ccid3hctx_x);
+ next_tmout = max_t(u32, 2 * usecs_div(hctx->ccid3hctx_s,
+ hctx->ccid3hctx_x),
+ TFRC_INITIAL_TIMEOUT);
+ /*
+ * FIXME - not sure above calculation is correct. See section
+ * 5 of CCID3 11 should adjust tx_t_ipi and double that to
+ * achieve it really
+ */
+ break;
+ case TFRC_SSTATE_FBACK:
+ /*
+ * Check if IDLE since last timeout and recv rate is less than
+ * 4 packets per RTT
+ */
+ if (!hctx->ccid3hctx_idle ||
+ (hctx->ccid3hctx_x_recv >=
+ 4 * usecs_div(hctx->ccid3hctx_s, hctx->ccid3hctx_rtt))) {
+ ccid3_pr_debug("%s, sk=%p, state=%s, not idle\n",
+ dccp_role(sk), sk,
+ ccid3_tx_state_name(hctx->ccid3hctx_state));
+ /* Halve sending rate */
+
+ /* If (X_calc > 2 * X_recv)
+ * X_recv = max(X_recv / 2, s / (2 * t_mbi));
+ * Else
+ * X_recv = X_calc / 4;
+ */
+ BUG_ON(hctx->ccid3hctx_p >= TFRC_SMALLEST_P &&
+ hctx->ccid3hctx_x_calc == 0);
+
+ /* check also if p is zero -> x_calc is infinity? */
+ if (hctx->ccid3hctx_p < TFRC_SMALLEST_P ||
+ hctx->ccid3hctx_x_calc > 2 * hctx->ccid3hctx_x_recv)
+ hctx->ccid3hctx_x_recv = max_t(u32, hctx->ccid3hctx_x_recv / 2,
+ hctx->ccid3hctx_s / (2 * TFRC_MAX_BACK_OFF_TIME));
+ else
+ hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc / 4;
+
+ /* Update sending rate */
+ ccid3_hc_tx_update_x(sk);
+ }
+ /*
+ * Schedule no feedback timer to expire in
+ * max(4 * R, 2 * s / X)
+ */
+ next_tmout = max_t(u32, hctx->ccid3hctx_t_rto,
+ 2 * usecs_div(hctx->ccid3hctx_s,
+ hctx->ccid3hctx_x));
+ break;
+ default:
+ printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
+ __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state);
+ dump_stack();
+ goto out;
+ }
+
+ sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
+ jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout)));
+ hctx->ccid3hctx_idle = 1;
+out:
+ bh_unlock_sock(sk);
+ sock_put(sk);
+}
+
+static int ccid3_hc_tx_send_packet(struct sock *sk,
+ struct sk_buff *skb, int len)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+ struct dccp_tx_hist_entry *new_packet;
+ struct timeval now;
+ long delay;
+ int rc = -ENOTCONN;
+
+ /* Check if pure ACK or Terminating*/
+
+ /*
+ * XXX: We only call this function for DATA and DATAACK, on, these
+ * packets can have zero length, but why the comment about "pure ACK"?
+ */
+ if (hctx == NULL || len == 0 ||
+ hctx->ccid3hctx_state == TFRC_SSTATE_TERM)
+ goto out;
+
+ /* See if last packet allocated was not sent */
+ new_packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist);
+ if (new_packet == NULL || new_packet->dccphtx_sent) {
+ new_packet = dccp_tx_hist_entry_new(ccid3_tx_hist,
+ SLAB_ATOMIC);
+
+ rc = -ENOBUFS;
+ if (new_packet == NULL) {
+ ccid3_pr_debug("%s, sk=%p, not enough mem to add "
+ "to history, send refused\n",
+ dccp_role(sk), sk);
+ goto out;
+ }
+
+ dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, new_packet);
+ }
+
+ do_gettimeofday(&now);
+
+ switch (hctx->ccid3hctx_state) {
+ case TFRC_SSTATE_NO_SENT:
+ ccid3_pr_debug("%s, sk=%p, first packet(%llu)\n",
+ dccp_role(sk), sk, dp->dccps_gss);
+
+ hctx->ccid3hctx_no_feedback_timer.function = ccid3_hc_tx_no_feedback_timer;
+ hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk;
+ sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
+ jiffies + usecs_to_jiffies(TFRC_INITIAL_TIMEOUT));
+ hctx->ccid3hctx_last_win_count = 0;
+ hctx->ccid3hctx_t_last_win_count = now;
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
+ hctx->ccid3hctx_t_ipi = TFRC_INITIAL_TIMEOUT;
+
+ /* Set nominal send time for initial packet */
+ hctx->ccid3hctx_t_nom = now;
+ timeval_add_usecs(&hctx->ccid3hctx_t_nom,
+ hctx->ccid3hctx_t_ipi);
+ ccid3_calc_new_delta(hctx);
+ rc = 0;
+ break;
+ case TFRC_SSTATE_NO_FBACK:
+ case TFRC_SSTATE_FBACK:
+ delay = (timeval_delta(&now, &hctx->ccid3hctx_t_nom) -
+ hctx->ccid3hctx_delta);
+ ccid3_pr_debug("send_packet delay=%ld\n", delay);
+ delay /= -1000;
+ /* divide by -1000 is to convert to ms and get sign right */
+ rc = delay > 0 ? delay : 0;
+ break;
+ default:
+ printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
+ __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state);
+ dump_stack();
+ rc = -EINVAL;
+ break;
+ }
+
+ /* Can we send? if so add options and add to packet history */
+ if (rc == 0)
+ new_packet->dccphtx_ccval =
+ DCCP_SKB_CB(skb)->dccpd_ccval =
+ hctx->ccid3hctx_last_win_count;
+out:
+ return rc;
+}
+
+static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, int len)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+ struct timeval now;
+
+ BUG_ON(hctx == NULL);
+
+ if (hctx->ccid3hctx_state == TFRC_SSTATE_TERM) {
+ ccid3_pr_debug("%s, sk=%p, while state is TFRC_SSTATE_TERM!\n",
+ dccp_role(sk), sk);
+ return;
+ }
+
+ do_gettimeofday(&now);
+
+ /* check if we have sent a data packet */
+ if (len > 0) {
+ unsigned long quarter_rtt;
+ struct dccp_tx_hist_entry *packet;
+
+ packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist);
+ if (packet == NULL) {
+ printk(KERN_CRIT "%s: packet doesn't exists in "
+ "history!\n", __FUNCTION__);
+ return;
+ }
+ if (packet->dccphtx_sent) {
+ printk(KERN_CRIT "%s: no unsent packet in history!\n",
+ __FUNCTION__);
+ return;
+ }
+ packet->dccphtx_tstamp = now;
+ packet->dccphtx_seqno = dp->dccps_gss;
+ /*
+ * Check if win_count have changed
+ * Algorithm in "8.1. Window Counter Valuer" in
+ * draft-ietf-dccp-ccid3-11.txt
+ */
+ quarter_rtt = timeval_delta(&now, &hctx->ccid3hctx_t_last_win_count);
+ if (likely(hctx->ccid3hctx_rtt > 8))
+ quarter_rtt /= hctx->ccid3hctx_rtt / 4;
+
+ if (quarter_rtt > 0) {
+ hctx->ccid3hctx_t_last_win_count = now;
+ hctx->ccid3hctx_last_win_count = (hctx->ccid3hctx_last_win_count +
+ min_t(unsigned long, quarter_rtt, 5)) % 16;
+ ccid3_pr_debug("%s, sk=%p, window changed from "
+ "%u to %u!\n",
+ dccp_role(sk), sk,
+ packet->dccphtx_ccval,
+ hctx->ccid3hctx_last_win_count);
+ }
+
+ hctx->ccid3hctx_idle = 0;
+ packet->dccphtx_rtt = hctx->ccid3hctx_rtt;
+ packet->dccphtx_sent = 1;
+ } else
+ ccid3_pr_debug("%s, sk=%p, seqno=%llu NOT inserted!\n",
+ dccp_role(sk), sk, dp->dccps_gss);
+
+ switch (hctx->ccid3hctx_state) {
+ case TFRC_SSTATE_NO_SENT:
+ /* if first wasn't pure ack */
+ if (len != 0)
+ printk(KERN_CRIT "%s: %s, First packet sent is noted "
+ "as a data packet\n",
+ __FUNCTION__, dccp_role(sk));
+ return;
+ case TFRC_SSTATE_NO_FBACK:
+ case TFRC_SSTATE_FBACK:
+ if (len > 0) {
+ hctx->ccid3hctx_t_nom = now;
+ ccid3_calc_new_t_ipi(hctx);
+ ccid3_calc_new_delta(hctx);
+ timeval_add_usecs(&hctx->ccid3hctx_t_nom,
+ hctx->ccid3hctx_t_ipi);
+ }
+ break;
+ default:
+ printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
+ __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state);
+ dump_stack();
+ break;
+ }
+}
+
+static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+ struct ccid3_options_received *opt_recv;
+ struct dccp_tx_hist_entry *packet;
+ unsigned long next_tmout;
+ u32 t_elapsed;
+ u32 pinv;
+ u32 x_recv;
+ u32 r_sample;
+
+ if (hctx == NULL)
+ return;
+
+ if (hctx->ccid3hctx_state == TFRC_SSTATE_TERM) {
+ ccid3_pr_debug("%s, sk=%p, received a packet when "
+ "terminating!\n", dccp_role(sk), sk);
+ return;
+ }
+
+ /* we are only interested in ACKs */
+ if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK ||
+ DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK))
+ return;
+
+ opt_recv = &hctx->ccid3hctx_options_received;
+
+ t_elapsed = dp->dccps_options_received.dccpor_elapsed_time;
+ x_recv = opt_recv->ccid3or_receive_rate;
+ pinv = opt_recv->ccid3or_loss_event_rate;
+
+ switch (hctx->ccid3hctx_state) {
+ case TFRC_SSTATE_NO_SENT:
+ /* FIXME: what to do here? */
+ return;
+ case TFRC_SSTATE_NO_FBACK:
+ case TFRC_SSTATE_FBACK:
+ /* Calculate new round trip sample by
+ * R_sample = (now - t_recvdata) - t_delay */
+ /* get t_recvdata from history */
+ packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist,
+ DCCP_SKB_CB(skb)->dccpd_ack_seq);
+ if (packet == NULL) {
+ ccid3_pr_debug("%s, sk=%p, seqno %llu(%s) does't "
+ "exist in history!\n",
+ dccp_role(sk), sk,
+ DCCP_SKB_CB(skb)->dccpd_ack_seq,
+ dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type));
+ return;
+ }
+
+ /* Update RTT */
+ r_sample = timeval_now_delta(&packet->dccphtx_tstamp);
+ /* FIXME: */
+ // r_sample -= usecs_to_jiffies(t_elapsed * 10);
+
+ /* Update RTT estimate by
+ * If (No feedback recv)
+ * R = R_sample;
+ * Else
+ * R = q * R + (1 - q) * R_sample;
+ *
+ * q is a constant, RFC 3448 recomments 0.9
+ */
+ if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) {
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK);
+ hctx->ccid3hctx_rtt = r_sample;
+ } else
+ hctx->ccid3hctx_rtt = (hctx->ccid3hctx_rtt * 9) / 10 +
+ r_sample / 10;
+
+ ccid3_pr_debug("%s, sk=%p, New RTT estimate=%uus, "
+ "r_sample=%us\n", dccp_role(sk), sk,
+ hctx->ccid3hctx_rtt, r_sample);
+
+ /* Update timeout interval */
+ hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt,
+ USEC_PER_SEC);
+
+ /* Update receive rate */
+ hctx->ccid3hctx_x_recv = x_recv;/* X_recv in bytes per sec */
+
+ /* Update loss event rate */
+ if (pinv == ~0 || pinv == 0)
+ hctx->ccid3hctx_p = 0;
+ else {
+ hctx->ccid3hctx_p = 1000000 / pinv;
+
+ if (hctx->ccid3hctx_p < TFRC_SMALLEST_P) {
+ hctx->ccid3hctx_p = TFRC_SMALLEST_P;
+ ccid3_pr_debug("%s, sk=%p, Smallest p used!\n",
+ dccp_role(sk), sk);
+ }
+ }
+
+ /* unschedule no feedback timer */
+ sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
+
+ /* Update sending rate */
+ ccid3_hc_tx_update_x(sk);
+
+ /* Update next send time */
+ timeval_sub_usecs(&hctx->ccid3hctx_t_nom,
+ hctx->ccid3hctx_t_ipi);
+ ccid3_calc_new_t_ipi(hctx);
+ timeval_add_usecs(&hctx->ccid3hctx_t_nom,
+ hctx->ccid3hctx_t_ipi);
+ ccid3_calc_new_delta(hctx);
+
+ /* remove all packets older than the one acked from history */
+ dccp_tx_hist_purge_older(ccid3_tx_hist,
+ &hctx->ccid3hctx_hist, packet);
+ /*
+ * As we have calculated new ipi, delta, t_nom it is possible that
+ * we now can send a packet, so wake up dccp_wait_for_ccids.
+ */
+ sk->sk_write_space(sk);
+
+ /*
+ * Schedule no feedback timer to expire in
+ * max(4 * R, 2 * s / X)
+ */
+ next_tmout = max(hctx->ccid3hctx_t_rto,
+ 2 * usecs_div(hctx->ccid3hctx_s,
+ hctx->ccid3hctx_x));
+
+ ccid3_pr_debug("%s, sk=%p, Scheduled no feedback timer to "
+ "expire in %lu jiffies (%luus)\n",
+ dccp_role(sk), sk,
+ usecs_to_jiffies(next_tmout), next_tmout);
+
+ sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
+ jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout)));
+
+ /* set idle flag */
+ hctx->ccid3hctx_idle = 1;
+ break;
+ default:
+ printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
+ __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state);
+ dump_stack();
+ break;
+ }
+}
+
+static void ccid3_hc_tx_insert_options(struct sock *sk, struct sk_buff *skb)
+{
+ const struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+
+ if (hctx == NULL || !(sk->sk_state == DCCP_OPEN ||
+ sk->sk_state == DCCP_PARTOPEN))
+ return;
+
+ DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count;
+}
+
+static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
+ unsigned char len, u16 idx,
+ unsigned char *value)
+{
+ int rc = 0;
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+ struct ccid3_options_received *opt_recv;
+
+ if (hctx == NULL)
+ return 0;
+
+ opt_recv = &hctx->ccid3hctx_options_received;
+
+ if (opt_recv->ccid3or_seqno != dp->dccps_gsr) {
+ opt_recv->ccid3or_seqno = dp->dccps_gsr;
+ opt_recv->ccid3or_loss_event_rate = ~0;
+ opt_recv->ccid3or_loss_intervals_idx = 0;
+ opt_recv->ccid3or_loss_intervals_len = 0;
+ opt_recv->ccid3or_receive_rate = 0;
+ }
+
+ switch (option) {
+ case TFRC_OPT_LOSS_EVENT_RATE:
+ if (len != 4) {
+ ccid3_pr_debug("%s, sk=%p, invalid len for "
+ "TFRC_OPT_LOSS_EVENT_RATE\n",
+ dccp_role(sk), sk);
+ rc = -EINVAL;
+ } else {
+ opt_recv->ccid3or_loss_event_rate = ntohl(*(u32 *)value);
+ ccid3_pr_debug("%s, sk=%p, LOSS_EVENT_RATE=%u\n",
+ dccp_role(sk), sk,
+ opt_recv->ccid3or_loss_event_rate);
+ }
+ break;
+ case TFRC_OPT_LOSS_INTERVALS:
+ opt_recv->ccid3or_loss_intervals_idx = idx;
+ opt_recv->ccid3or_loss_intervals_len = len;
+ ccid3_pr_debug("%s, sk=%p, LOSS_INTERVALS=(%u, %u)\n",
+ dccp_role(sk), sk,
+ opt_recv->ccid3or_loss_intervals_idx,
+ opt_recv->ccid3or_loss_intervals_len);
+ break;
+ case TFRC_OPT_RECEIVE_RATE:
+ if (len != 4) {
+ ccid3_pr_debug("%s, sk=%p, invalid len for "
+ "TFRC_OPT_RECEIVE_RATE\n",
+ dccp_role(sk), sk);
+ rc = -EINVAL;
+ } else {
+ opt_recv->ccid3or_receive_rate = ntohl(*(u32 *)value);
+ ccid3_pr_debug("%s, sk=%p, RECEIVE_RATE=%u\n",
+ dccp_role(sk), sk,
+ opt_recv->ccid3or_receive_rate);
+ }
+ break;
+ }
+
+ return rc;
+}
+
+static int ccid3_hc_tx_init(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx;
+
+ ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
+
+ hctx = dp->dccps_hc_tx_ccid_private = kmalloc(sizeof(*hctx),
+ gfp_any());
+ if (hctx == NULL)
+ return -ENOMEM;
+
+ memset(hctx, 0, sizeof(*hctx));
+
+ if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE &&
+ dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE)
+ hctx->ccid3hctx_s = dp->dccps_packet_size;
+ else
+ hctx->ccid3hctx_s = TFRC_STD_PACKET_SIZE;
+
+ /* Set transmission rate to 1 packet per second */
+ hctx->ccid3hctx_x = hctx->ccid3hctx_s;
+ hctx->ccid3hctx_t_rto = USEC_PER_SEC;
+ hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT;
+ INIT_LIST_HEAD(&hctx->ccid3hctx_hist);
+ init_timer(&hctx->ccid3hctx_no_feedback_timer);
+
+ return 0;
+}
+
+static void ccid3_hc_tx_exit(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+
+ ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
+ BUG_ON(hctx == NULL);
+
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM);
+ sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
+
+ /* Empty packet history */
+ dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist);
+
+ kfree(dp->dccps_hc_tx_ccid_private);
+ dp->dccps_hc_tx_ccid_private = NULL;
+}
+
+/*
+ * RX Half Connection methods
+ */
+
+/* TFRC receiver states */
+enum ccid3_hc_rx_states {
+ TFRC_RSTATE_NO_DATA = 1,
+ TFRC_RSTATE_DATA,
+ TFRC_RSTATE_TERM = 127,
+};
+
+#ifdef CCID3_DEBUG
+static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state)
+{
+ static char *ccid3_rx_state_names[] = {
+ [TFRC_RSTATE_NO_DATA] = "NO_DATA",
+ [TFRC_RSTATE_DATA] = "DATA",
+ [TFRC_RSTATE_TERM] = "TERM",
+ };
+
+ return ccid3_rx_state_names[state];
+}
+#endif
+
+static inline void ccid3_hc_rx_set_state(struct sock *sk,
+ enum ccid3_hc_rx_states state)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+ enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state;
+
+ ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
+ dccp_role(sk), sk, ccid3_rx_state_name(oldstate),
+ ccid3_rx_state_name(state));
+ WARN_ON(state == oldstate);
+ hcrx->ccid3hcrx_state = state;
+}
+
+static void ccid3_hc_rx_send_feedback(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+ struct dccp_rx_hist_entry *packet;
+ struct timeval now;
+
+ ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
+
+ do_gettimeofday(&now);
+
+ switch (hcrx->ccid3hcrx_state) {
+ case TFRC_RSTATE_NO_DATA:
+ hcrx->ccid3hcrx_x_recv = 0;
+ break;
+ case TFRC_RSTATE_DATA: {
+ const u32 delta = timeval_delta(&now,
+ &hcrx->ccid3hcrx_tstamp_last_feedback);
+
+ hcrx->ccid3hcrx_x_recv = (hcrx->ccid3hcrx_bytes_recv *
+ USEC_PER_SEC);
+ if (likely(delta > 1))
+ hcrx->ccid3hcrx_x_recv /= delta;
+ }
+ break;
+ default:
+ printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
+ __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state);
+ dump_stack();
+ return;
+ }
+
+ packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist);
+ if (packet == NULL) {
+ printk(KERN_CRIT "%s: %s, sk=%p, no data packet in history!\n",
+ __FUNCTION__, dccp_role(sk), sk);
+ dump_stack();
+ return;
+ }
+
+ hcrx->ccid3hcrx_tstamp_last_feedback = now;
+ hcrx->ccid3hcrx_last_counter = packet->dccphrx_ccval;
+ hcrx->ccid3hcrx_seqno_last_counter = packet->dccphrx_seqno;
+ hcrx->ccid3hcrx_bytes_recv = 0;
+
+ /* Convert to multiples of 10us */
+ hcrx->ccid3hcrx_elapsed_time =
+ timeval_delta(&now, &packet->dccphrx_tstamp) / 10;
+ if (hcrx->ccid3hcrx_p == 0)
+ hcrx->ccid3hcrx_pinv = ~0;
+ else
+ hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p;
+ dccp_send_ack(sk);
+}
+
+static void ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
+{
+ const struct dccp_sock *dp = dccp_sk(sk);
+ u32 x_recv, pinv;
+ struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+
+ if (hcrx == NULL || !(sk->sk_state == DCCP_OPEN ||
+ sk->sk_state == DCCP_PARTOPEN))
+ return;
+
+ DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_last_counter;
+
+ if (dccp_packet_without_ack(skb))
+ return;
+
+ if (hcrx->ccid3hcrx_elapsed_time != 0)
+ dccp_insert_option_elapsed_time(sk, skb,
+ hcrx->ccid3hcrx_elapsed_time);
+ dccp_insert_option_timestamp(sk, skb);
+ x_recv = htonl(hcrx->ccid3hcrx_x_recv);
+ pinv = htonl(hcrx->ccid3hcrx_pinv);
+ dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE,
+ &pinv, sizeof(pinv));
+ dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE,
+ &x_recv, sizeof(x_recv));
+}
+
+/* calculate first loss interval
+ *
+ * returns estimated loss interval in usecs */
+
+static u32 ccid3_hc_rx_calc_first_li(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+ struct dccp_rx_hist_entry *entry, *next, *tail = NULL;
+ u32 rtt, delta, x_recv, fval, p, tmp2;
+ struct timeval tstamp = { 0, };
+ int interval = 0;
+ int win_count = 0;
+ int step = 0;
+ u64 tmp1;
+
+ list_for_each_entry_safe(entry, next, &hcrx->ccid3hcrx_hist,
+ dccphrx_node) {
+ if (dccp_rx_hist_entry_data_packet(entry)) {
+ tail = entry;
+
+ switch (step) {
+ case 0:
+ tstamp = entry->dccphrx_tstamp;
+ win_count = entry->dccphrx_ccval;
+ step = 1;
+ break;
+ case 1:
+ interval = win_count - entry->dccphrx_ccval;
+ if (interval < 0)
+ interval += TFRC_WIN_COUNT_LIMIT;
+ if (interval > 4)
+ goto found;
+ break;
+ }
+ }
+ }
+
+ if (step == 0) {
+ printk(KERN_CRIT "%s: %s, sk=%p, packet history contains no "
+ "data packets!\n",
+ __FUNCTION__, dccp_role(sk), sk);
+ return ~0;
+ }
+
+ if (interval == 0) {
+ ccid3_pr_debug("%s, sk=%p, Could not find a win_count "
+ "interval > 0. Defaulting to 1\n",
+ dccp_role(sk), sk);
+ interval = 1;
+ }
+found:
+ rtt = timeval_delta(&tstamp, &tail->dccphrx_tstamp) * 4 / interval;
+ ccid3_pr_debug("%s, sk=%p, approximated RTT to %uus\n",
+ dccp_role(sk), sk, rtt);
+ if (rtt == 0)
+ rtt = 1;
+
+ delta = timeval_now_delta(&hcrx->ccid3hcrx_tstamp_last_feedback);
+ x_recv = hcrx->ccid3hcrx_bytes_recv * USEC_PER_SEC;
+ if (likely(delta > 1))
+ x_recv /= delta;
+
+ tmp1 = (u64)x_recv * (u64)rtt;
+ do_div(tmp1,10000000);
+ tmp2 = (u32)tmp1;
+ fval = (hcrx->ccid3hcrx_s * 100000) / tmp2;
+ /* do not alter order above or you will get overflow on 32 bit */
+ p = tfrc_calc_x_reverse_lookup(fval);
+ ccid3_pr_debug("%s, sk=%p, receive rate=%u bytes/s, implied "
+ "loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
+
+ if (p == 0)
+ return ~0;
+ else
+ return 1000000 / p;
+}
+
+static void ccid3_hc_rx_update_li(struct sock *sk, u64 seq_loss, u8 win_loss)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+
+ if (seq_loss != DCCP_MAX_SEQNO + 1 &&
+ list_empty(&hcrx->ccid3hcrx_li_hist)) {
+ struct dccp_li_hist_entry *li_tail;
+
+ li_tail = dccp_li_hist_interval_new(ccid3_li_hist,
+ &hcrx->ccid3hcrx_li_hist,
+ seq_loss, win_loss);
+ if (li_tail == NULL)
+ return;
+ li_tail->dccplih_interval = ccid3_hc_rx_calc_first_li(sk);
+ }
+ /* FIXME: find end of interval */
+}
+
+static void ccid3_hc_rx_detect_loss(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+ u8 win_loss;
+ const u64 seq_loss = dccp_rx_hist_detect_loss(&hcrx->ccid3hcrx_hist,
+ &hcrx->ccid3hcrx_li_hist,
+ &win_loss);
+
+ ccid3_hc_rx_update_li(sk, seq_loss, win_loss);
+}
+
+static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+ const struct dccp_options_received *opt_recv;
+ struct dccp_rx_hist_entry *packet;
+ struct timeval now;
+ u8 win_count;
+ u32 p_prev;
+ int ins;
+
+ if (hcrx == NULL)
+ return;
+
+ BUG_ON(!(hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA ||
+ hcrx->ccid3hcrx_state == TFRC_RSTATE_DATA));
+
+ opt_recv = &dp->dccps_options_received;
+
+ switch (DCCP_SKB_CB(skb)->dccpd_type) {
+ case DCCP_PKT_ACK:
+ if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
+ return;
+ case DCCP_PKT_DATAACK:
+ if (opt_recv->dccpor_timestamp_echo == 0)
+ break;
+ p_prev = hcrx->ccid3hcrx_rtt;
+ do_gettimeofday(&now);
+ hcrx->ccid3hcrx_rtt = timeval_usecs(&now) -
+ (opt_recv->dccpor_timestamp_echo -
+ opt_recv->dccpor_elapsed_time) * 10;
+ if (p_prev != hcrx->ccid3hcrx_rtt)
+ ccid3_pr_debug("%s, New RTT=%luus, elapsed time=%u\n",
+ dccp_role(sk), hcrx->ccid3hcrx_rtt,
+ opt_recv->dccpor_elapsed_time);
+ break;
+ case DCCP_PKT_DATA:
+ break;
+ default:
+ ccid3_pr_debug("%s, sk=%p, not DATA/DATAACK/ACK packet(%s)\n",
+ dccp_role(sk), sk,
+ dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type));
+ return;
+ }
+
+ packet = dccp_rx_hist_entry_new(ccid3_rx_hist, opt_recv->dccpor_ndp,
+ skb, SLAB_ATOMIC);
+ if (packet == NULL) {
+ ccid3_pr_debug("%s, sk=%p, Not enough mem to add rx packet "
+ "to history (consider it lost)!",
+ dccp_role(sk), sk);
+ return;
+ }
+
+ win_count = packet->dccphrx_ccval;
+
+ ins = dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist,
+ &hcrx->ccid3hcrx_li_hist, packet);
+
+ if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK)
+ return;
+
+ switch (hcrx->ccid3hcrx_state) {
+ case TFRC_RSTATE_NO_DATA:
+ ccid3_pr_debug("%s, sk=%p(%s), skb=%p, sending initial "
+ "feedback\n",
+ dccp_role(sk), sk,
+ dccp_state_name(sk->sk_state), skb);
+ ccid3_hc_rx_send_feedback(sk);
+ ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA);
+ return;
+ case TFRC_RSTATE_DATA:
+ hcrx->ccid3hcrx_bytes_recv += skb->len -
+ dccp_hdr(skb)->dccph_doff * 4;
+ if (ins != 0)
+ break;
+
+ do_gettimeofday(&now);
+ if (timeval_delta(&now, &hcrx->ccid3hcrx_tstamp_last_ack) >=
+ hcrx->ccid3hcrx_rtt) {
+ hcrx->ccid3hcrx_tstamp_last_ack = now;
+ ccid3_hc_rx_send_feedback(sk);
+ }
+ return;
+ default:
+ printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
+ __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state);
+ dump_stack();
+ return;
+ }
+
+ /* Dealing with packet loss */
+ ccid3_pr_debug("%s, sk=%p(%s), data loss! Reacting...\n",
+ dccp_role(sk), sk, dccp_state_name(sk->sk_state));
+
+ ccid3_hc_rx_detect_loss(sk);
+ p_prev = hcrx->ccid3hcrx_p;
+
+ /* Calculate loss event rate */
+ if (!list_empty(&hcrx->ccid3hcrx_li_hist))
+ /* Scaling up by 1000000 as fixed decimal */
+ hcrx->ccid3hcrx_p = 1000000 / dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist);
+
+ if (hcrx->ccid3hcrx_p > p_prev) {
+ ccid3_hc_rx_send_feedback(sk);
+ return;
+ }
+}
+
+static int ccid3_hc_rx_init(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_rx_sock *hcrx;
+
+ ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
+
+ hcrx = dp->dccps_hc_rx_ccid_private = kmalloc(sizeof(*hcrx),
+ gfp_any());
+ if (hcrx == NULL)
+ return -ENOMEM;
+
+ memset(hcrx, 0, sizeof(*hcrx));
+
+ if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE &&
+ dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE)
+ hcrx->ccid3hcrx_s = dp->dccps_packet_size;
+ else
+ hcrx->ccid3hcrx_s = TFRC_STD_PACKET_SIZE;
+
+ hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA;
+ INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist);
+ INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist);
+ /*
+ * XXX this seems to be paranoid, need to think more about this, for
+ * now start with something different than zero. -acme
+ */
+ hcrx->ccid3hcrx_rtt = USEC_PER_SEC / 5;
+ return 0;
+}
+
+static void ccid3_hc_rx_exit(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+
+ ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
+
+ if (hcrx == NULL)
+ return;
+
+ ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM);
+
+ /* Empty packet history */
+ dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist);
+
+ /* Empty loss interval history */
+ dccp_li_hist_purge(ccid3_li_hist, &hcrx->ccid3hcrx_li_hist);
+
+ kfree(dp->dccps_hc_rx_ccid_private);
+ dp->dccps_hc_rx_ccid_private = NULL;
+}
+
+static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info)
+{
+ const struct dccp_sock *dp = dccp_sk(sk);
+ const struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
+
+ if (hcrx == NULL)
+ return;
+
+ info->tcpi_ca_state = hcrx->ccid3hcrx_state;
+ info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
+ info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt;
+}
+
+static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info)
+{
+ const struct dccp_sock *dp = dccp_sk(sk);
+ const struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
+
+ if (hctx == NULL)
+ return;
+
+ info->tcpi_rto = hctx->ccid3hctx_t_rto;
+ info->tcpi_rtt = hctx->ccid3hctx_rtt;
+}
+
+static struct ccid ccid3 = {
+ .ccid_id = 3,
+ .ccid_name = "ccid3",
+ .ccid_owner = THIS_MODULE,
+ .ccid_init = ccid3_init,
+ .ccid_exit = ccid3_exit,
+ .ccid_hc_tx_init = ccid3_hc_tx_init,
+ .ccid_hc_tx_exit = ccid3_hc_tx_exit,
+ .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet,
+ .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent,
+ .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv,
+ .ccid_hc_tx_insert_options = ccid3_hc_tx_insert_options,
+ .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options,
+ .ccid_hc_rx_init = ccid3_hc_rx_init,
+ .ccid_hc_rx_exit = ccid3_hc_rx_exit,
+ .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options,
+ .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv,
+ .ccid_hc_rx_get_info = ccid3_hc_rx_get_info,
+ .ccid_hc_tx_get_info = ccid3_hc_tx_get_info,
+};
+
+module_param(ccid3_debug, int, 0444);
+MODULE_PARM_DESC(ccid3_debug, "Enable debug messages");
+
+static __init int ccid3_module_init(void)
+{
+ int rc = -ENOBUFS;
+
+ ccid3_rx_hist = dccp_rx_hist_new("ccid3");
+ if (ccid3_rx_hist == NULL)
+ goto out;
+
+ ccid3_tx_hist = dccp_tx_hist_new("ccid3");
+ if (ccid3_tx_hist == NULL)
+ goto out_free_rx;
+
+ ccid3_li_hist = dccp_li_hist_new("ccid3");
+ if (ccid3_li_hist == NULL)
+ goto out_free_tx;
+
+ rc = ccid_register(&ccid3);
+ if (rc != 0)
+ goto out_free_loss_interval_history;
+out:
+ return rc;
+
+out_free_loss_interval_history:
+ dccp_li_hist_delete(ccid3_li_hist);
+ ccid3_li_hist = NULL;
+out_free_tx:
+ dccp_tx_hist_delete(ccid3_tx_hist);
+ ccid3_tx_hist = NULL;
+out_free_rx:
+ dccp_rx_hist_delete(ccid3_rx_hist);
+ ccid3_rx_hist = NULL;
+ goto out;
+}
+module_init(ccid3_module_init);
+
+static __exit void ccid3_module_exit(void)
+{
+#ifdef CONFIG_IP_DCCP_UNLOAD_HACK
+ /*
+ * Hack to use while developing, so that we get rid of the control
+ * sock, that is what keeps a refcount on dccp.ko -acme
+ */
+ extern void dccp_ctl_sock_exit(void);
+
+ dccp_ctl_sock_exit();
+#endif
+ ccid_unregister(&ccid3);
+
+ if (ccid3_tx_hist != NULL) {
+ dccp_tx_hist_delete(ccid3_tx_hist);
+ ccid3_tx_hist = NULL;
+ }
+ if (ccid3_rx_hist != NULL) {
+ dccp_rx_hist_delete(ccid3_rx_hist);
+ ccid3_rx_hist = NULL;
+ }
+ if (ccid3_li_hist != NULL) {
+ dccp_li_hist_delete(ccid3_li_hist);
+ ccid3_li_hist = NULL;
+ }
+}
+module_exit(ccid3_module_exit);
+
+MODULE_AUTHOR("Ian McDonald <iam4@cs.waikato.ac.nz>, "
+ "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>");
+MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("net-dccp-ccid-3");