diff options
Diffstat (limited to 'net/dccp/ccids/ccid3.c')
-rw-r--r-- | net/dccp/ccids/ccid3.c | 1221 |
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 | */ | ||
48 | static 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 | |||
54 | static 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 | |||
65 | static struct dccp_tx_hist *ccid3_tx_hist; | ||
66 | static struct dccp_rx_hist *ccid3_rx_hist; | ||
67 | static struct dccp_li_hist *ccid3_li_hist; | ||
68 | |||
69 | static int ccid3_init(struct sock *sk) | ||
70 | { | ||
71 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | ||
72 | return 0; | ||
73 | } | ||
74 | |||
75 | static 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 */ | ||
81 | enum 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 | ||
89 | static 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 | |||
102 | static 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 */ | ||
117 | static 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) */ | ||
129 | static 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 | */ | ||
145 | static 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 | |||
174 | static 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; | ||
268 | out: | ||
269 | bh_unlock_sock(sk); | ||
270 | sock_put(sk); | ||
271 | } | ||
272 | |||
273 | static 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; | ||
355 | out: | ||
356 | return rc; | ||
357 | } | ||
358 | |||
359 | static 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 | |||
446 | static 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 | |||
592 | static 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 | |||
604 | static 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 | |||
666 | static 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 | |||
696 | static 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 */ | ||
719 | enum 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 | ||
726 | static 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 | |||
738 | static 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 | |||
752 | static 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 | |||
807 | static 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 | |||
838 | static 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 | } | ||
885 | found: | ||
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 | |||
912 | static 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 | |||
931 | static 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 | |||
943 | static 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 | |||
1052 | static 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 | |||
1083 | static 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 | |||
1105 | static 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 | |||
1118 | static 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 | |||
1130 | static 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 | |||
1151 | module_param(ccid3_debug, int, 0444); | ||
1152 | MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); | ||
1153 | |||
1154 | static __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; | ||
1173 | out: | ||
1174 | return rc; | ||
1175 | |||
1176 | out_free_loss_interval_history: | ||
1177 | dccp_li_hist_delete(ccid3_li_hist); | ||
1178 | ccid3_li_hist = NULL; | ||
1179 | out_free_tx: | ||
1180 | dccp_tx_hist_delete(ccid3_tx_hist); | ||
1181 | ccid3_tx_hist = NULL; | ||
1182 | out_free_rx: | ||
1183 | dccp_rx_hist_delete(ccid3_rx_hist); | ||
1184 | ccid3_rx_hist = NULL; | ||
1185 | goto out; | ||
1186 | } | ||
1187 | module_init(ccid3_module_init); | ||
1188 | |||
1189 | static __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 | } | ||
1215 | module_exit(ccid3_module_exit); | ||
1216 | |||
1217 | MODULE_AUTHOR("Ian McDonald <iam4@cs.waikato.ac.nz>, " | ||
1218 | "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); | ||
1219 | MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); | ||
1220 | MODULE_LICENSE("GPL"); | ||
1221 | MODULE_ALIAS("net-dccp-ccid-3"); | ||