aboutsummaryrefslogtreecommitdiffstats
path: root/net/dccp/ccids/ccid3.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/dccp/ccids/ccid3.c')
-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 @@
1/*
2 * net/dccp/ccids/ccid3.c
3 *
4 * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
5 * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz>
6 *
7 * An implementation of the DCCP protocol
8 *
9 * This code has been developed by the University of Waikato WAND
10 * research group. For further information please see http://www.wand.net.nz/
11 *
12 * This code also uses code from Lulea University, rereleased as GPL by its
13 * authors:
14 * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
15 *
16 * Changes to meet Linux coding standards, to make it meet latest ccid3 draft
17 * and to make it work as a loadable module in the DCCP stack written by
18 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>.
19 *
20 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
21 *
22 * This program is free software; you can redistribute it and/or modify
23 * it under the terms of the GNU General Public License as published by
24 * the Free Software Foundation; either version 2 of the License, or
25 * (at your option) any later version.
26 *
27 * This program is distributed in the hope that it will be useful,
28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
30 * GNU General Public License for more details.
31 *
32 * You should have received a copy of the GNU General Public License
33 * along with this program; if not, write to the Free Software
34 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
35 */
36
37#include <linux/config.h>
38#include "../ccid.h"
39#include "../dccp.h"
40#include "lib/packet_history.h"
41#include "lib/loss_interval.h"
42#include "lib/tfrc.h"
43#include "ccid3.h"
44
45/*
46 * Reason for maths with 10 here is to avoid 32 bit overflow when a is big.
47 */
48static inline u32 usecs_div(const u32 a, const u32 b)
49{
50 const u32 tmp = a * (USEC_PER_SEC / 10);
51 return b > 20 ? tmp / (b / 10) : tmp;
52}
53
54static int ccid3_debug;
55
56#ifdef CCID3_DEBUG
57#define ccid3_pr_debug(format, a...) \
58 do { if (ccid3_debug) \
59 printk(KERN_DEBUG "%s: " format, __FUNCTION__, ##a); \
60 } while (0)
61#else
62#define ccid3_pr_debug(format, a...)
63#endif
64
65static struct dccp_tx_hist *ccid3_tx_hist;
66static struct dccp_rx_hist *ccid3_rx_hist;
67static struct dccp_li_hist *ccid3_li_hist;
68
69static int ccid3_init(struct sock *sk)
70{
71 ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
72 return 0;
73}
74
75static void ccid3_exit(struct sock *sk)
76{
77 ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
78}
79
80/* TFRC sender states */
81enum ccid3_hc_tx_states {
82 TFRC_SSTATE_NO_SENT = 1,
83 TFRC_SSTATE_NO_FBACK,
84 TFRC_SSTATE_FBACK,
85 TFRC_SSTATE_TERM,
86};
87
88#ifdef CCID3_DEBUG
89static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state)
90{
91 static char *ccid3_state_names[] = {
92 [TFRC_SSTATE_NO_SENT] = "NO_SENT",
93 [TFRC_SSTATE_NO_FBACK] = "NO_FBACK",
94 [TFRC_SSTATE_FBACK] = "FBACK",
95 [TFRC_SSTATE_TERM] = "TERM",
96 };
97
98 return ccid3_state_names[state];
99}
100#endif
101
102static inline void ccid3_hc_tx_set_state(struct sock *sk,
103 enum ccid3_hc_tx_states state)
104{
105 struct dccp_sock *dp = dccp_sk(sk);
106 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
107 enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state;
108
109 ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
110 dccp_role(sk), sk, ccid3_tx_state_name(oldstate),
111 ccid3_tx_state_name(state));
112 WARN_ON(state == oldstate);
113 hctx->ccid3hctx_state = state;
114}
115
116/* Calculate new t_ipi (inter packet interval) by t_ipi = s / X_inst */
117static inline void ccid3_calc_new_t_ipi(struct ccid3_hc_tx_sock *hctx)
118{
119 /*
120 * If no feedback spec says t_ipi is 1 second (set elsewhere and then
121 * doubles after every no feedback timer (separate function)
122 */
123 if (hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK)
124 hctx->ccid3hctx_t_ipi = usecs_div(hctx->ccid3hctx_s,
125 hctx->ccid3hctx_x);
126}
127
128/* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */
129static inline void ccid3_calc_new_delta(struct ccid3_hc_tx_sock *hctx)
130{
131 hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2,
132 TFRC_OPSYS_HALF_TIME_GRAN);
133}
134
135/*
136 * Update X by
137 * If (p > 0)
138 * x_calc = calcX(s, R, p);
139 * X = max(min(X_calc, 2 * X_recv), s / t_mbi);
140 * Else
141 * If (now - tld >= R)
142 * X = max(min(2 * X, 2 * X_recv), s / R);
143 * tld = now;
144 */
145static void ccid3_hc_tx_update_x(struct sock *sk)
146{
147 struct dccp_sock *dp = dccp_sk(sk);
148 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
149
150 /* To avoid large error in calcX */
151 if (hctx->ccid3hctx_p >= TFRC_SMALLEST_P) {
152 hctx->ccid3hctx_x_calc = tfrc_calc_x(hctx->ccid3hctx_s,
153 hctx->ccid3hctx_rtt,
154 hctx->ccid3hctx_p);
155 hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_calc,
156 2 * hctx->ccid3hctx_x_recv),
157 (hctx->ccid3hctx_s /
158 TFRC_MAX_BACK_OFF_TIME));
159 } else {
160 struct timeval now;
161
162 do_gettimeofday(&now);
163 if (timeval_delta(&now, &hctx->ccid3hctx_t_ld) >=
164 hctx->ccid3hctx_rtt) {
165 hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_recv,
166 hctx->ccid3hctx_x) * 2,
167 usecs_div(hctx->ccid3hctx_s,
168 hctx->ccid3hctx_rtt));
169 hctx->ccid3hctx_t_ld = now;
170 }
171 }
172}
173
174static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
175{
176 struct sock *sk = (struct sock *)data;
177 struct dccp_sock *dp = dccp_sk(sk);
178 unsigned long next_tmout = 0;
179 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
180
181 bh_lock_sock(sk);
182 if (sock_owned_by_user(sk)) {
183 /* Try again later. */
184 /* XXX: set some sensible MIB */
185 sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
186 jiffies + HZ / 5);
187 goto out;
188 }
189
190 ccid3_pr_debug("%s, sk=%p, state=%s\n", dccp_role(sk), sk,
191 ccid3_tx_state_name(hctx->ccid3hctx_state));
192
193 switch (hctx->ccid3hctx_state) {
194 case TFRC_SSTATE_TERM:
195 goto out;
196 case TFRC_SSTATE_NO_FBACK:
197 /* Halve send rate */
198 hctx->ccid3hctx_x /= 2;
199 if (hctx->ccid3hctx_x < (hctx->ccid3hctx_s /
200 TFRC_MAX_BACK_OFF_TIME))
201 hctx->ccid3hctx_x = (hctx->ccid3hctx_s /
202 TFRC_MAX_BACK_OFF_TIME);
203
204 ccid3_pr_debug("%s, sk=%p, state=%s, updated tx rate to %d "
205 "bytes/s\n",
206 dccp_role(sk), sk,
207 ccid3_tx_state_name(hctx->ccid3hctx_state),
208 hctx->ccid3hctx_x);
209 next_tmout = max_t(u32, 2 * usecs_div(hctx->ccid3hctx_s,
210 hctx->ccid3hctx_x),
211 TFRC_INITIAL_TIMEOUT);
212 /*
213 * FIXME - not sure above calculation is correct. See section
214 * 5 of CCID3 11 should adjust tx_t_ipi and double that to
215 * achieve it really
216 */
217 break;
218 case TFRC_SSTATE_FBACK:
219 /*
220 * Check if IDLE since last timeout and recv rate is less than
221 * 4 packets per RTT
222 */
223 if (!hctx->ccid3hctx_idle ||
224 (hctx->ccid3hctx_x_recv >=
225 4 * usecs_div(hctx->ccid3hctx_s, hctx->ccid3hctx_rtt))) {
226 ccid3_pr_debug("%s, sk=%p, state=%s, not idle\n",
227 dccp_role(sk), sk,
228 ccid3_tx_state_name(hctx->ccid3hctx_state));
229 /* Halve sending rate */
230
231 /* If (X_calc > 2 * X_recv)
232 * X_recv = max(X_recv / 2, s / (2 * t_mbi));
233 * Else
234 * X_recv = X_calc / 4;
235 */
236 BUG_ON(hctx->ccid3hctx_p >= TFRC_SMALLEST_P &&
237 hctx->ccid3hctx_x_calc == 0);
238
239 /* check also if p is zero -> x_calc is infinity? */
240 if (hctx->ccid3hctx_p < TFRC_SMALLEST_P ||
241 hctx->ccid3hctx_x_calc > 2 * hctx->ccid3hctx_x_recv)
242 hctx->ccid3hctx_x_recv = max_t(u32, hctx->ccid3hctx_x_recv / 2,
243 hctx->ccid3hctx_s / (2 * TFRC_MAX_BACK_OFF_TIME));
244 else
245 hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc / 4;
246
247 /* Update sending rate */
248 ccid3_hc_tx_update_x(sk);
249 }
250 /*
251 * Schedule no feedback timer to expire in
252 * max(4 * R, 2 * s / X)
253 */
254 next_tmout = max_t(u32, hctx->ccid3hctx_t_rto,
255 2 * usecs_div(hctx->ccid3hctx_s,
256 hctx->ccid3hctx_x));
257 break;
258 default:
259 printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
260 __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state);
261 dump_stack();
262 goto out;
263 }
264
265 sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
266 jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout)));
267 hctx->ccid3hctx_idle = 1;
268out:
269 bh_unlock_sock(sk);
270 sock_put(sk);
271}
272
273static int ccid3_hc_tx_send_packet(struct sock *sk,
274 struct sk_buff *skb, int len)
275{
276 struct dccp_sock *dp = dccp_sk(sk);
277 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
278 struct dccp_tx_hist_entry *new_packet;
279 struct timeval now;
280 long delay;
281 int rc = -ENOTCONN;
282
283 /* Check if pure ACK or Terminating*/
284
285 /*
286 * XXX: We only call this function for DATA and DATAACK, on, these
287 * packets can have zero length, but why the comment about "pure ACK"?
288 */
289 if (hctx == NULL || len == 0 ||
290 hctx->ccid3hctx_state == TFRC_SSTATE_TERM)
291 goto out;
292
293 /* See if last packet allocated was not sent */
294 new_packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist);
295 if (new_packet == NULL || new_packet->dccphtx_sent) {
296 new_packet = dccp_tx_hist_entry_new(ccid3_tx_hist,
297 SLAB_ATOMIC);
298
299 rc = -ENOBUFS;
300 if (new_packet == NULL) {
301 ccid3_pr_debug("%s, sk=%p, not enough mem to add "
302 "to history, send refused\n",
303 dccp_role(sk), sk);
304 goto out;
305 }
306
307 dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, new_packet);
308 }
309
310 do_gettimeofday(&now);
311
312 switch (hctx->ccid3hctx_state) {
313 case TFRC_SSTATE_NO_SENT:
314 ccid3_pr_debug("%s, sk=%p, first packet(%llu)\n",
315 dccp_role(sk), sk, dp->dccps_gss);
316
317 hctx->ccid3hctx_no_feedback_timer.function = ccid3_hc_tx_no_feedback_timer;
318 hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk;
319 sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
320 jiffies + usecs_to_jiffies(TFRC_INITIAL_TIMEOUT));
321 hctx->ccid3hctx_last_win_count = 0;
322 hctx->ccid3hctx_t_last_win_count = now;
323 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
324 hctx->ccid3hctx_t_ipi = TFRC_INITIAL_TIMEOUT;
325
326 /* Set nominal send time for initial packet */
327 hctx->ccid3hctx_t_nom = now;
328 timeval_add_usecs(&hctx->ccid3hctx_t_nom,
329 hctx->ccid3hctx_t_ipi);
330 ccid3_calc_new_delta(hctx);
331 rc = 0;
332 break;
333 case TFRC_SSTATE_NO_FBACK:
334 case TFRC_SSTATE_FBACK:
335 delay = (timeval_delta(&now, &hctx->ccid3hctx_t_nom) -
336 hctx->ccid3hctx_delta);
337 ccid3_pr_debug("send_packet delay=%ld\n", delay);
338 delay /= -1000;
339 /* divide by -1000 is to convert to ms and get sign right */
340 rc = delay > 0 ? delay : 0;
341 break;
342 default:
343 printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
344 __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state);
345 dump_stack();
346 rc = -EINVAL;
347 break;
348 }
349
350 /* Can we send? if so add options and add to packet history */
351 if (rc == 0)
352 new_packet->dccphtx_ccval =
353 DCCP_SKB_CB(skb)->dccpd_ccval =
354 hctx->ccid3hctx_last_win_count;
355out:
356 return rc;
357}
358
359static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, int len)
360{
361 struct dccp_sock *dp = dccp_sk(sk);
362 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
363 struct timeval now;
364
365 BUG_ON(hctx == NULL);
366
367 if (hctx->ccid3hctx_state == TFRC_SSTATE_TERM) {
368 ccid3_pr_debug("%s, sk=%p, while state is TFRC_SSTATE_TERM!\n",
369 dccp_role(sk), sk);
370 return;
371 }
372
373 do_gettimeofday(&now);
374
375 /* check if we have sent a data packet */
376 if (len > 0) {
377 unsigned long quarter_rtt;
378 struct dccp_tx_hist_entry *packet;
379
380 packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist);
381 if (packet == NULL) {
382 printk(KERN_CRIT "%s: packet doesn't exists in "
383 "history!\n", __FUNCTION__);
384 return;
385 }
386 if (packet->dccphtx_sent) {
387 printk(KERN_CRIT "%s: no unsent packet in history!\n",
388 __FUNCTION__);
389 return;
390 }
391 packet->dccphtx_tstamp = now;
392 packet->dccphtx_seqno = dp->dccps_gss;
393 /*
394 * Check if win_count have changed
395 * Algorithm in "8.1. Window Counter Valuer" in
396 * draft-ietf-dccp-ccid3-11.txt
397 */
398 quarter_rtt = timeval_delta(&now, &hctx->ccid3hctx_t_last_win_count);
399 if (likely(hctx->ccid3hctx_rtt > 8))
400 quarter_rtt /= hctx->ccid3hctx_rtt / 4;
401
402 if (quarter_rtt > 0) {
403 hctx->ccid3hctx_t_last_win_count = now;
404 hctx->ccid3hctx_last_win_count = (hctx->ccid3hctx_last_win_count +
405 min_t(unsigned long, quarter_rtt, 5)) % 16;
406 ccid3_pr_debug("%s, sk=%p, window changed from "
407 "%u to %u!\n",
408 dccp_role(sk), sk,
409 packet->dccphtx_ccval,
410 hctx->ccid3hctx_last_win_count);
411 }
412
413 hctx->ccid3hctx_idle = 0;
414 packet->dccphtx_rtt = hctx->ccid3hctx_rtt;
415 packet->dccphtx_sent = 1;
416 } else
417 ccid3_pr_debug("%s, sk=%p, seqno=%llu NOT inserted!\n",
418 dccp_role(sk), sk, dp->dccps_gss);
419
420 switch (hctx->ccid3hctx_state) {
421 case TFRC_SSTATE_NO_SENT:
422 /* if first wasn't pure ack */
423 if (len != 0)
424 printk(KERN_CRIT "%s: %s, First packet sent is noted "
425 "as a data packet\n",
426 __FUNCTION__, dccp_role(sk));
427 return;
428 case TFRC_SSTATE_NO_FBACK:
429 case TFRC_SSTATE_FBACK:
430 if (len > 0) {
431 hctx->ccid3hctx_t_nom = now;
432 ccid3_calc_new_t_ipi(hctx);
433 ccid3_calc_new_delta(hctx);
434 timeval_add_usecs(&hctx->ccid3hctx_t_nom,
435 hctx->ccid3hctx_t_ipi);
436 }
437 break;
438 default:
439 printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
440 __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state);
441 dump_stack();
442 break;
443 }
444}
445
446static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
447{
448 struct dccp_sock *dp = dccp_sk(sk);
449 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
450 struct ccid3_options_received *opt_recv;
451 struct dccp_tx_hist_entry *packet;
452 unsigned long next_tmout;
453 u32 t_elapsed;
454 u32 pinv;
455 u32 x_recv;
456 u32 r_sample;
457
458 if (hctx == NULL)
459 return;
460
461 if (hctx->ccid3hctx_state == TFRC_SSTATE_TERM) {
462 ccid3_pr_debug("%s, sk=%p, received a packet when "
463 "terminating!\n", dccp_role(sk), sk);
464 return;
465 }
466
467 /* we are only interested in ACKs */
468 if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK ||
469 DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK))
470 return;
471
472 opt_recv = &hctx->ccid3hctx_options_received;
473
474 t_elapsed = dp->dccps_options_received.dccpor_elapsed_time;
475 x_recv = opt_recv->ccid3or_receive_rate;
476 pinv = opt_recv->ccid3or_loss_event_rate;
477
478 switch (hctx->ccid3hctx_state) {
479 case TFRC_SSTATE_NO_SENT:
480 /* FIXME: what to do here? */
481 return;
482 case TFRC_SSTATE_NO_FBACK:
483 case TFRC_SSTATE_FBACK:
484 /* Calculate new round trip sample by
485 * R_sample = (now - t_recvdata) - t_delay */
486 /* get t_recvdata from history */
487 packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist,
488 DCCP_SKB_CB(skb)->dccpd_ack_seq);
489 if (packet == NULL) {
490 ccid3_pr_debug("%s, sk=%p, seqno %llu(%s) does't "
491 "exist in history!\n",
492 dccp_role(sk), sk,
493 DCCP_SKB_CB(skb)->dccpd_ack_seq,
494 dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type));
495 return;
496 }
497
498 /* Update RTT */
499 r_sample = timeval_now_delta(&packet->dccphtx_tstamp);
500 /* FIXME: */
501 // r_sample -= usecs_to_jiffies(t_elapsed * 10);
502
503 /* Update RTT estimate by
504 * If (No feedback recv)
505 * R = R_sample;
506 * Else
507 * R = q * R + (1 - q) * R_sample;
508 *
509 * q is a constant, RFC 3448 recomments 0.9
510 */
511 if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) {
512 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK);
513 hctx->ccid3hctx_rtt = r_sample;
514 } else
515 hctx->ccid3hctx_rtt = (hctx->ccid3hctx_rtt * 9) / 10 +
516 r_sample / 10;
517
518 ccid3_pr_debug("%s, sk=%p, New RTT estimate=%uus, "
519 "r_sample=%us\n", dccp_role(sk), sk,
520 hctx->ccid3hctx_rtt, r_sample);
521
522 /* Update timeout interval */
523 hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt,
524 USEC_PER_SEC);
525
526 /* Update receive rate */
527 hctx->ccid3hctx_x_recv = x_recv;/* X_recv in bytes per sec */
528
529 /* Update loss event rate */
530 if (pinv == ~0 || pinv == 0)
531 hctx->ccid3hctx_p = 0;
532 else {
533 hctx->ccid3hctx_p = 1000000 / pinv;
534
535 if (hctx->ccid3hctx_p < TFRC_SMALLEST_P) {
536 hctx->ccid3hctx_p = TFRC_SMALLEST_P;
537 ccid3_pr_debug("%s, sk=%p, Smallest p used!\n",
538 dccp_role(sk), sk);
539 }
540 }
541
542 /* unschedule no feedback timer */
543 sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
544
545 /* Update sending rate */
546 ccid3_hc_tx_update_x(sk);
547
548 /* Update next send time */
549 timeval_sub_usecs(&hctx->ccid3hctx_t_nom,
550 hctx->ccid3hctx_t_ipi);
551 ccid3_calc_new_t_ipi(hctx);
552 timeval_add_usecs(&hctx->ccid3hctx_t_nom,
553 hctx->ccid3hctx_t_ipi);
554 ccid3_calc_new_delta(hctx);
555
556 /* remove all packets older than the one acked from history */
557 dccp_tx_hist_purge_older(ccid3_tx_hist,
558 &hctx->ccid3hctx_hist, packet);
559 /*
560 * As we have calculated new ipi, delta, t_nom it is possible that
561 * we now can send a packet, so wake up dccp_wait_for_ccids.
562 */
563 sk->sk_write_space(sk);
564
565 /*
566 * Schedule no feedback timer to expire in
567 * max(4 * R, 2 * s / X)
568 */
569 next_tmout = max(hctx->ccid3hctx_t_rto,
570 2 * usecs_div(hctx->ccid3hctx_s,
571 hctx->ccid3hctx_x));
572
573 ccid3_pr_debug("%s, sk=%p, Scheduled no feedback timer to "
574 "expire in %lu jiffies (%luus)\n",
575 dccp_role(sk), sk,
576 usecs_to_jiffies(next_tmout), next_tmout);
577
578 sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
579 jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout)));
580
581 /* set idle flag */
582 hctx->ccid3hctx_idle = 1;
583 break;
584 default:
585 printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
586 __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state);
587 dump_stack();
588 break;
589 }
590}
591
592static void ccid3_hc_tx_insert_options(struct sock *sk, struct sk_buff *skb)
593{
594 const struct dccp_sock *dp = dccp_sk(sk);
595 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
596
597 if (hctx == NULL || !(sk->sk_state == DCCP_OPEN ||
598 sk->sk_state == DCCP_PARTOPEN))
599 return;
600
601 DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count;
602}
603
604static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
605 unsigned char len, u16 idx,
606 unsigned char *value)
607{
608 int rc = 0;
609 struct dccp_sock *dp = dccp_sk(sk);
610 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
611 struct ccid3_options_received *opt_recv;
612
613 if (hctx == NULL)
614 return 0;
615
616 opt_recv = &hctx->ccid3hctx_options_received;
617
618 if (opt_recv->ccid3or_seqno != dp->dccps_gsr) {
619 opt_recv->ccid3or_seqno = dp->dccps_gsr;
620 opt_recv->ccid3or_loss_event_rate = ~0;
621 opt_recv->ccid3or_loss_intervals_idx = 0;
622 opt_recv->ccid3or_loss_intervals_len = 0;
623 opt_recv->ccid3or_receive_rate = 0;
624 }
625
626 switch (option) {
627 case TFRC_OPT_LOSS_EVENT_RATE:
628 if (len != 4) {
629 ccid3_pr_debug("%s, sk=%p, invalid len for "
630 "TFRC_OPT_LOSS_EVENT_RATE\n",
631 dccp_role(sk), sk);
632 rc = -EINVAL;
633 } else {
634 opt_recv->ccid3or_loss_event_rate = ntohl(*(u32 *)value);
635 ccid3_pr_debug("%s, sk=%p, LOSS_EVENT_RATE=%u\n",
636 dccp_role(sk), sk,
637 opt_recv->ccid3or_loss_event_rate);
638 }
639 break;
640 case TFRC_OPT_LOSS_INTERVALS:
641 opt_recv->ccid3or_loss_intervals_idx = idx;
642 opt_recv->ccid3or_loss_intervals_len = len;
643 ccid3_pr_debug("%s, sk=%p, LOSS_INTERVALS=(%u, %u)\n",
644 dccp_role(sk), sk,
645 opt_recv->ccid3or_loss_intervals_idx,
646 opt_recv->ccid3or_loss_intervals_len);
647 break;
648 case TFRC_OPT_RECEIVE_RATE:
649 if (len != 4) {
650 ccid3_pr_debug("%s, sk=%p, invalid len for "
651 "TFRC_OPT_RECEIVE_RATE\n",
652 dccp_role(sk), sk);
653 rc = -EINVAL;
654 } else {
655 opt_recv->ccid3or_receive_rate = ntohl(*(u32 *)value);
656 ccid3_pr_debug("%s, sk=%p, RECEIVE_RATE=%u\n",
657 dccp_role(sk), sk,
658 opt_recv->ccid3or_receive_rate);
659 }
660 break;
661 }
662
663 return rc;
664}
665
666static int ccid3_hc_tx_init(struct sock *sk)
667{
668 struct dccp_sock *dp = dccp_sk(sk);
669 struct ccid3_hc_tx_sock *hctx;
670
671 ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
672
673 hctx = dp->dccps_hc_tx_ccid_private = kmalloc(sizeof(*hctx),
674 gfp_any());
675 if (hctx == NULL)
676 return -ENOMEM;
677
678 memset(hctx, 0, sizeof(*hctx));
679
680 if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE &&
681 dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE)
682 hctx->ccid3hctx_s = dp->dccps_packet_size;
683 else
684 hctx->ccid3hctx_s = TFRC_STD_PACKET_SIZE;
685
686 /* Set transmission rate to 1 packet per second */
687 hctx->ccid3hctx_x = hctx->ccid3hctx_s;
688 hctx->ccid3hctx_t_rto = USEC_PER_SEC;
689 hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT;
690 INIT_LIST_HEAD(&hctx->ccid3hctx_hist);
691 init_timer(&hctx->ccid3hctx_no_feedback_timer);
692
693 return 0;
694}
695
696static void ccid3_hc_tx_exit(struct sock *sk)
697{
698 struct dccp_sock *dp = dccp_sk(sk);
699 struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
700
701 ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
702 BUG_ON(hctx == NULL);
703
704 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM);
705 sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
706
707 /* Empty packet history */
708 dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist);
709
710 kfree(dp->dccps_hc_tx_ccid_private);
711 dp->dccps_hc_tx_ccid_private = NULL;
712}
713
714/*
715 * RX Half Connection methods
716 */
717
718/* TFRC receiver states */
719enum ccid3_hc_rx_states {
720 TFRC_RSTATE_NO_DATA = 1,
721 TFRC_RSTATE_DATA,
722 TFRC_RSTATE_TERM = 127,
723};
724
725#ifdef CCID3_DEBUG
726static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state)
727{
728 static char *ccid3_rx_state_names[] = {
729 [TFRC_RSTATE_NO_DATA] = "NO_DATA",
730 [TFRC_RSTATE_DATA] = "DATA",
731 [TFRC_RSTATE_TERM] = "TERM",
732 };
733
734 return ccid3_rx_state_names[state];
735}
736#endif
737
738static inline void ccid3_hc_rx_set_state(struct sock *sk,
739 enum ccid3_hc_rx_states state)
740{
741 struct dccp_sock *dp = dccp_sk(sk);
742 struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
743 enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state;
744
745 ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
746 dccp_role(sk), sk, ccid3_rx_state_name(oldstate),
747 ccid3_rx_state_name(state));
748 WARN_ON(state == oldstate);
749 hcrx->ccid3hcrx_state = state;
750}
751
752static void ccid3_hc_rx_send_feedback(struct sock *sk)
753{
754 struct dccp_sock *dp = dccp_sk(sk);
755 struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
756 struct dccp_rx_hist_entry *packet;
757 struct timeval now;
758
759 ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
760
761 do_gettimeofday(&now);
762
763 switch (hcrx->ccid3hcrx_state) {
764 case TFRC_RSTATE_NO_DATA:
765 hcrx->ccid3hcrx_x_recv = 0;
766 break;
767 case TFRC_RSTATE_DATA: {
768 const u32 delta = timeval_delta(&now,
769 &hcrx->ccid3hcrx_tstamp_last_feedback);
770
771 hcrx->ccid3hcrx_x_recv = (hcrx->ccid3hcrx_bytes_recv *
772 USEC_PER_SEC);
773 if (likely(delta > 1))
774 hcrx->ccid3hcrx_x_recv /= delta;
775 }
776 break;
777 default:
778 printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
779 __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state);
780 dump_stack();
781 return;
782 }
783
784 packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist);
785 if (packet == NULL) {
786 printk(KERN_CRIT "%s: %s, sk=%p, no data packet in history!\n",
787 __FUNCTION__, dccp_role(sk), sk);
788 dump_stack();
789 return;
790 }
791
792 hcrx->ccid3hcrx_tstamp_last_feedback = now;
793 hcrx->ccid3hcrx_last_counter = packet->dccphrx_ccval;
794 hcrx->ccid3hcrx_seqno_last_counter = packet->dccphrx_seqno;
795 hcrx->ccid3hcrx_bytes_recv = 0;
796
797 /* Convert to multiples of 10us */
798 hcrx->ccid3hcrx_elapsed_time =
799 timeval_delta(&now, &packet->dccphrx_tstamp) / 10;
800 if (hcrx->ccid3hcrx_p == 0)
801 hcrx->ccid3hcrx_pinv = ~0;
802 else
803 hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p;
804 dccp_send_ack(sk);
805}
806
807static void ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
808{
809 const struct dccp_sock *dp = dccp_sk(sk);
810 u32 x_recv, pinv;
811 struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
812
813 if (hcrx == NULL || !(sk->sk_state == DCCP_OPEN ||
814 sk->sk_state == DCCP_PARTOPEN))
815 return;
816
817 DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_last_counter;
818
819 if (dccp_packet_without_ack(skb))
820 return;
821
822 if (hcrx->ccid3hcrx_elapsed_time != 0)
823 dccp_insert_option_elapsed_time(sk, skb,
824 hcrx->ccid3hcrx_elapsed_time);
825 dccp_insert_option_timestamp(sk, skb);
826 x_recv = htonl(hcrx->ccid3hcrx_x_recv);
827 pinv = htonl(hcrx->ccid3hcrx_pinv);
828 dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE,
829 &pinv, sizeof(pinv));
830 dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE,
831 &x_recv, sizeof(x_recv));
832}
833
834/* calculate first loss interval
835 *
836 * returns estimated loss interval in usecs */
837
838static u32 ccid3_hc_rx_calc_first_li(struct sock *sk)
839{
840 struct dccp_sock *dp = dccp_sk(sk);
841 struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
842 struct dccp_rx_hist_entry *entry, *next, *tail = NULL;
843 u32 rtt, delta, x_recv, fval, p, tmp2;
844 struct timeval tstamp = { 0, };
845 int interval = 0;
846 int win_count = 0;
847 int step = 0;
848 u64 tmp1;
849
850 list_for_each_entry_safe(entry, next, &hcrx->ccid3hcrx_hist,
851 dccphrx_node) {
852 if (dccp_rx_hist_entry_data_packet(entry)) {
853 tail = entry;
854
855 switch (step) {
856 case 0:
857 tstamp = entry->dccphrx_tstamp;
858 win_count = entry->dccphrx_ccval;
859 step = 1;
860 break;
861 case 1:
862 interval = win_count - entry->dccphrx_ccval;
863 if (interval < 0)
864 interval += TFRC_WIN_COUNT_LIMIT;
865 if (interval > 4)
866 goto found;
867 break;
868 }
869 }
870 }
871
872 if (step == 0) {
873 printk(KERN_CRIT "%s: %s, sk=%p, packet history contains no "
874 "data packets!\n",
875 __FUNCTION__, dccp_role(sk), sk);
876 return ~0;
877 }
878
879 if (interval == 0) {
880 ccid3_pr_debug("%s, sk=%p, Could not find a win_count "
881 "interval > 0. Defaulting to 1\n",
882 dccp_role(sk), sk);
883 interval = 1;
884 }
885found:
886 rtt = timeval_delta(&tstamp, &tail->dccphrx_tstamp) * 4 / interval;
887 ccid3_pr_debug("%s, sk=%p, approximated RTT to %uus\n",
888 dccp_role(sk), sk, rtt);
889 if (rtt == 0)
890 rtt = 1;
891
892 delta = timeval_now_delta(&hcrx->ccid3hcrx_tstamp_last_feedback);
893 x_recv = hcrx->ccid3hcrx_bytes_recv * USEC_PER_SEC;
894 if (likely(delta > 1))
895 x_recv /= delta;
896
897 tmp1 = (u64)x_recv * (u64)rtt;
898 do_div(tmp1,10000000);
899 tmp2 = (u32)tmp1;
900 fval = (hcrx->ccid3hcrx_s * 100000) / tmp2;
901 /* do not alter order above or you will get overflow on 32 bit */
902 p = tfrc_calc_x_reverse_lookup(fval);
903 ccid3_pr_debug("%s, sk=%p, receive rate=%u bytes/s, implied "
904 "loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
905
906 if (p == 0)
907 return ~0;
908 else
909 return 1000000 / p;
910}
911
912static void ccid3_hc_rx_update_li(struct sock *sk, u64 seq_loss, u8 win_loss)
913{
914 struct dccp_sock *dp = dccp_sk(sk);
915 struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
916
917 if (seq_loss != DCCP_MAX_SEQNO + 1 &&
918 list_empty(&hcrx->ccid3hcrx_li_hist)) {
919 struct dccp_li_hist_entry *li_tail;
920
921 li_tail = dccp_li_hist_interval_new(ccid3_li_hist,
922 &hcrx->ccid3hcrx_li_hist,
923 seq_loss, win_loss);
924 if (li_tail == NULL)
925 return;
926 li_tail->dccplih_interval = ccid3_hc_rx_calc_first_li(sk);
927 }
928 /* FIXME: find end of interval */
929}
930
931static void ccid3_hc_rx_detect_loss(struct sock *sk)
932{
933 struct dccp_sock *dp = dccp_sk(sk);
934 struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
935 u8 win_loss;
936 const u64 seq_loss = dccp_rx_hist_detect_loss(&hcrx->ccid3hcrx_hist,
937 &hcrx->ccid3hcrx_li_hist,
938 &win_loss);
939
940 ccid3_hc_rx_update_li(sk, seq_loss, win_loss);
941}
942
943static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
944{
945 struct dccp_sock *dp = dccp_sk(sk);
946 struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
947 const struct dccp_options_received *opt_recv;
948 struct dccp_rx_hist_entry *packet;
949 struct timeval now;
950 u8 win_count;
951 u32 p_prev;
952 int ins;
953
954 if (hcrx == NULL)
955 return;
956
957 BUG_ON(!(hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA ||
958 hcrx->ccid3hcrx_state == TFRC_RSTATE_DATA));
959
960 opt_recv = &dp->dccps_options_received;
961
962 switch (DCCP_SKB_CB(skb)->dccpd_type) {
963 case DCCP_PKT_ACK:
964 if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
965 return;
966 case DCCP_PKT_DATAACK:
967 if (opt_recv->dccpor_timestamp_echo == 0)
968 break;
969 p_prev = hcrx->ccid3hcrx_rtt;
970 do_gettimeofday(&now);
971 hcrx->ccid3hcrx_rtt = timeval_usecs(&now) -
972 (opt_recv->dccpor_timestamp_echo -
973 opt_recv->dccpor_elapsed_time) * 10;
974 if (p_prev != hcrx->ccid3hcrx_rtt)
975 ccid3_pr_debug("%s, New RTT=%luus, elapsed time=%u\n",
976 dccp_role(sk), hcrx->ccid3hcrx_rtt,
977 opt_recv->dccpor_elapsed_time);
978 break;
979 case DCCP_PKT_DATA:
980 break;
981 default:
982 ccid3_pr_debug("%s, sk=%p, not DATA/DATAACK/ACK packet(%s)\n",
983 dccp_role(sk), sk,
984 dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type));
985 return;
986 }
987
988 packet = dccp_rx_hist_entry_new(ccid3_rx_hist, opt_recv->dccpor_ndp,
989 skb, SLAB_ATOMIC);
990 if (packet == NULL) {
991 ccid3_pr_debug("%s, sk=%p, Not enough mem to add rx packet "
992 "to history (consider it lost)!",
993 dccp_role(sk), sk);
994 return;
995 }
996
997 win_count = packet->dccphrx_ccval;
998
999 ins = dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist,
1000 &hcrx->ccid3hcrx_li_hist, packet);
1001
1002 if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK)
1003 return;
1004
1005 switch (hcrx->ccid3hcrx_state) {
1006 case TFRC_RSTATE_NO_DATA:
1007 ccid3_pr_debug("%s, sk=%p(%s), skb=%p, sending initial "
1008 "feedback\n",
1009 dccp_role(sk), sk,
1010 dccp_state_name(sk->sk_state), skb);
1011 ccid3_hc_rx_send_feedback(sk);
1012 ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA);
1013 return;
1014 case TFRC_RSTATE_DATA:
1015 hcrx->ccid3hcrx_bytes_recv += skb->len -
1016 dccp_hdr(skb)->dccph_doff * 4;
1017 if (ins != 0)
1018 break;
1019
1020 do_gettimeofday(&now);
1021 if (timeval_delta(&now, &hcrx->ccid3hcrx_tstamp_last_ack) >=
1022 hcrx->ccid3hcrx_rtt) {
1023 hcrx->ccid3hcrx_tstamp_last_ack = now;
1024 ccid3_hc_rx_send_feedback(sk);
1025 }
1026 return;
1027 default:
1028 printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n",
1029 __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state);
1030 dump_stack();
1031 return;
1032 }
1033
1034 /* Dealing with packet loss */
1035 ccid3_pr_debug("%s, sk=%p(%s), data loss! Reacting...\n",
1036 dccp_role(sk), sk, dccp_state_name(sk->sk_state));
1037
1038 ccid3_hc_rx_detect_loss(sk);
1039 p_prev = hcrx->ccid3hcrx_p;
1040
1041 /* Calculate loss event rate */
1042 if (!list_empty(&hcrx->ccid3hcrx_li_hist))
1043 /* Scaling up by 1000000 as fixed decimal */
1044 hcrx->ccid3hcrx_p = 1000000 / dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist);
1045
1046 if (hcrx->ccid3hcrx_p > p_prev) {
1047 ccid3_hc_rx_send_feedback(sk);
1048 return;
1049 }
1050}
1051
1052static int ccid3_hc_rx_init(struct sock *sk)
1053{
1054 struct dccp_sock *dp = dccp_sk(sk);
1055 struct ccid3_hc_rx_sock *hcrx;
1056
1057 ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
1058
1059 hcrx = dp->dccps_hc_rx_ccid_private = kmalloc(sizeof(*hcrx),
1060 gfp_any());
1061 if (hcrx == NULL)
1062 return -ENOMEM;
1063
1064 memset(hcrx, 0, sizeof(*hcrx));
1065
1066 if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE &&
1067 dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE)
1068 hcrx->ccid3hcrx_s = dp->dccps_packet_size;
1069 else
1070 hcrx->ccid3hcrx_s = TFRC_STD_PACKET_SIZE;
1071
1072 hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA;
1073 INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist);
1074 INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist);
1075 /*
1076 * XXX this seems to be paranoid, need to think more about this, for
1077 * now start with something different than zero. -acme
1078 */
1079 hcrx->ccid3hcrx_rtt = USEC_PER_SEC / 5;
1080 return 0;
1081}
1082
1083static void ccid3_hc_rx_exit(struct sock *sk)
1084{
1085 struct dccp_sock *dp = dccp_sk(sk);
1086 struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
1087
1088 ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk);
1089
1090 if (hcrx == NULL)
1091 return;
1092
1093 ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM);
1094
1095 /* Empty packet history */
1096 dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist);
1097
1098 /* Empty loss interval history */
1099 dccp_li_hist_purge(ccid3_li_hist, &hcrx->ccid3hcrx_li_hist);
1100
1101 kfree(dp->dccps_hc_rx_ccid_private);
1102 dp->dccps_hc_rx_ccid_private = NULL;
1103}
1104
1105static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info)
1106{
1107 const struct dccp_sock *dp = dccp_sk(sk);
1108 const struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private;
1109
1110 if (hcrx == NULL)
1111 return;
1112
1113 info->tcpi_ca_state = hcrx->ccid3hcrx_state;
1114 info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1115 info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt;
1116}
1117
1118static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info)
1119{
1120 const struct dccp_sock *dp = dccp_sk(sk);
1121 const struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private;
1122
1123 if (hctx == NULL)
1124 return;
1125
1126 info->tcpi_rto = hctx->ccid3hctx_t_rto;
1127 info->tcpi_rtt = hctx->ccid3hctx_rtt;
1128}
1129
1130static struct ccid ccid3 = {
1131 .ccid_id = 3,
1132 .ccid_name = "ccid3",
1133 .ccid_owner = THIS_MODULE,
1134 .ccid_init = ccid3_init,
1135 .ccid_exit = ccid3_exit,
1136 .ccid_hc_tx_init = ccid3_hc_tx_init,
1137 .ccid_hc_tx_exit = ccid3_hc_tx_exit,
1138 .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet,
1139 .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent,
1140 .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv,
1141 .ccid_hc_tx_insert_options = ccid3_hc_tx_insert_options,
1142 .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options,
1143 .ccid_hc_rx_init = ccid3_hc_rx_init,
1144 .ccid_hc_rx_exit = ccid3_hc_rx_exit,
1145 .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options,
1146 .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv,
1147 .ccid_hc_rx_get_info = ccid3_hc_rx_get_info,
1148 .ccid_hc_tx_get_info = ccid3_hc_tx_get_info,
1149};
1150
1151module_param(ccid3_debug, int, 0444);
1152MODULE_PARM_DESC(ccid3_debug, "Enable debug messages");
1153
1154static __init int ccid3_module_init(void)
1155{
1156 int rc = -ENOBUFS;
1157
1158 ccid3_rx_hist = dccp_rx_hist_new("ccid3");
1159 if (ccid3_rx_hist == NULL)
1160 goto out;
1161
1162 ccid3_tx_hist = dccp_tx_hist_new("ccid3");
1163 if (ccid3_tx_hist == NULL)
1164 goto out_free_rx;
1165
1166 ccid3_li_hist = dccp_li_hist_new("ccid3");
1167 if (ccid3_li_hist == NULL)
1168 goto out_free_tx;
1169
1170 rc = ccid_register(&ccid3);
1171 if (rc != 0)
1172 goto out_free_loss_interval_history;
1173out:
1174 return rc;
1175
1176out_free_loss_interval_history:
1177 dccp_li_hist_delete(ccid3_li_hist);
1178 ccid3_li_hist = NULL;
1179out_free_tx:
1180 dccp_tx_hist_delete(ccid3_tx_hist);
1181 ccid3_tx_hist = NULL;
1182out_free_rx:
1183 dccp_rx_hist_delete(ccid3_rx_hist);
1184 ccid3_rx_hist = NULL;
1185 goto out;
1186}
1187module_init(ccid3_module_init);
1188
1189static __exit void ccid3_module_exit(void)
1190{
1191#ifdef CONFIG_IP_DCCP_UNLOAD_HACK
1192 /*
1193 * Hack to use while developing, so that we get rid of the control
1194 * sock, that is what keeps a refcount on dccp.ko -acme
1195 */
1196 extern void dccp_ctl_sock_exit(void);
1197
1198 dccp_ctl_sock_exit();
1199#endif
1200 ccid_unregister(&ccid3);
1201
1202 if (ccid3_tx_hist != NULL) {
1203 dccp_tx_hist_delete(ccid3_tx_hist);
1204 ccid3_tx_hist = NULL;
1205 }
1206 if (ccid3_rx_hist != NULL) {
1207 dccp_rx_hist_delete(ccid3_rx_hist);
1208 ccid3_rx_hist = NULL;
1209 }
1210 if (ccid3_li_hist != NULL) {
1211 dccp_li_hist_delete(ccid3_li_hist);
1212 ccid3_li_hist = NULL;
1213 }
1214}
1215module_exit(ccid3_module_exit);
1216
1217MODULE_AUTHOR("Ian McDonald <iam4@cs.waikato.ac.nz>, "
1218 "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>");
1219MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID");
1220MODULE_LICENSE("GPL");
1221MODULE_ALIAS("net-dccp-ccid-3");