Commit | Line | Data |
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7c657876 ACM |
1 | /* |
2 | * net/dccp/ccids/ccid3.c | |
3 | * | |
4 | * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. | |
1bc09869 | 5 | * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> |
7c657876 ACM |
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/ | |
7c657876 ACM |
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 | ||
8c60f3fa | 37 | #include <linux/config.h> |
7c657876 ACM |
38 | #include "../ccid.h" |
39 | #include "../dccp.h" | |
4524b259 | 40 | #include "lib/packet_history.h" |
ae6706f0 | 41 | #include "lib/loss_interval.h" |
36729c1a | 42 | #include "lib/tfrc.h" |
7c657876 ACM |
43 | #include "ccid3.h" |
44 | ||
6b5e633a | 45 | /* |
0ba7a3ba ACM |
46 | * Reason for maths here is to avoid 32 bit overflow when a is big. |
47 | * With this we get close to the limit. | |
6b5e633a ACM |
48 | */ |
49 | static inline u32 usecs_div(const u32 a, const u32 b) | |
50 | { | |
0ba7a3ba ACM |
51 | const u32 div = a < (UINT_MAX / (USEC_PER_SEC / 10)) ? 10 : |
52 | a < (UINT_MAX / (USEC_PER_SEC / 50)) ? 50 : | |
53 | a < (UINT_MAX / (USEC_PER_SEC / 100)) ? 100 : | |
54 | a < (UINT_MAX / (USEC_PER_SEC / 500)) ? 500 : | |
55 | a < (UINT_MAX / (USEC_PER_SEC / 1000)) ? 1000 : | |
56 | a < (UINT_MAX / (USEC_PER_SEC / 5000)) ? 5000 : | |
57 | a < (UINT_MAX / (USEC_PER_SEC / 10000)) ? 10000 : | |
58 | a < (UINT_MAX / (USEC_PER_SEC / 50000)) ? 50000 : | |
59 | 100000; | |
60 | const u32 tmp = a * (USEC_PER_SEC / div); | |
61 | return (b >= 2 * div) ? tmp / (b / div) : tmp; | |
6b5e633a ACM |
62 | } |
63 | ||
cfc3c525 | 64 | static int ccid3_debug; |
7c657876 | 65 | |
cfc3c525 | 66 | #ifdef CCID3_DEBUG |
7c657876 ACM |
67 | #define ccid3_pr_debug(format, a...) \ |
68 | do { if (ccid3_debug) \ | |
69 | printk(KERN_DEBUG "%s: " format, __FUNCTION__, ##a); \ | |
70 | } while (0) | |
71 | #else | |
72 | #define ccid3_pr_debug(format, a...) | |
73 | #endif | |
74 | ||
a1d3a355 ACM |
75 | static struct dccp_tx_hist *ccid3_tx_hist; |
76 | static struct dccp_rx_hist *ccid3_rx_hist; | |
ae6706f0 | 77 | static struct dccp_li_hist *ccid3_li_hist; |
7c657876 ACM |
78 | |
79 | static int ccid3_init(struct sock *sk) | |
80 | { | |
7c657876 ACM |
81 | return 0; |
82 | } | |
83 | ||
84 | static void ccid3_exit(struct sock *sk) | |
85 | { | |
7c657876 ACM |
86 | } |
87 | ||
88 | /* TFRC sender states */ | |
89 | enum ccid3_hc_tx_states { | |
90 | TFRC_SSTATE_NO_SENT = 1, | |
91 | TFRC_SSTATE_NO_FBACK, | |
92 | TFRC_SSTATE_FBACK, | |
93 | TFRC_SSTATE_TERM, | |
94 | }; | |
95 | ||
96 | #ifdef CCID3_DEBUG | |
97 | static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) | |
98 | { | |
99 | static char *ccid3_state_names[] = { | |
100 | [TFRC_SSTATE_NO_SENT] = "NO_SENT", | |
101 | [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", | |
102 | [TFRC_SSTATE_FBACK] = "FBACK", | |
103 | [TFRC_SSTATE_TERM] = "TERM", | |
104 | }; | |
105 | ||
106 | return ccid3_state_names[state]; | |
107 | } | |
108 | #endif | |
109 | ||
1f2333ae ACM |
110 | static inline void ccid3_hc_tx_set_state(struct sock *sk, |
111 | enum ccid3_hc_tx_states state) | |
7c657876 | 112 | { |
59725dc2 | 113 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 ACM |
114 | enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state; |
115 | ||
116 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | |
1f2333ae ACM |
117 | dccp_role(sk), sk, ccid3_tx_state_name(oldstate), |
118 | ccid3_tx_state_name(state)); | |
7c657876 ACM |
119 | WARN_ON(state == oldstate); |
120 | hctx->ccid3hctx_state = state; | |
121 | } | |
122 | ||
7c657876 ACM |
123 | /* Calculate new t_ipi (inter packet interval) by t_ipi = s / X_inst */ |
124 | static inline void ccid3_calc_new_t_ipi(struct ccid3_hc_tx_sock *hctx) | |
125 | { | |
6b5e633a ACM |
126 | /* |
127 | * If no feedback spec says t_ipi is 1 second (set elsewhere and then | |
128 | * doubles after every no feedback timer (separate function) | |
129 | */ | |
130 | if (hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK) | |
131 | hctx->ccid3hctx_t_ipi = usecs_div(hctx->ccid3hctx_s, | |
132 | hctx->ccid3hctx_x); | |
7c657876 ACM |
133 | } |
134 | ||
135 | /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ | |
136 | static inline void ccid3_calc_new_delta(struct ccid3_hc_tx_sock *hctx) | |
137 | { | |
1f2333ae ACM |
138 | hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2, |
139 | TFRC_OPSYS_HALF_TIME_GRAN); | |
7c657876 ACM |
140 | } |
141 | ||
142 | /* | |
143 | * Update X by | |
144 | * If (p > 0) | |
145 | * x_calc = calcX(s, R, p); | |
146 | * X = max(min(X_calc, 2 * X_recv), s / t_mbi); | |
147 | * Else | |
148 | * If (now - tld >= R) | |
149 | * X = max(min(2 * X, 2 * X_recv), s / R); | |
150 | * tld = now; | |
151 | */ | |
152 | static void ccid3_hc_tx_update_x(struct sock *sk) | |
153 | { | |
59725dc2 | 154 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 | 155 | |
1f2333ae ACM |
156 | /* To avoid large error in calcX */ |
157 | if (hctx->ccid3hctx_p >= TFRC_SMALLEST_P) { | |
36729c1a ACM |
158 | hctx->ccid3hctx_x_calc = tfrc_calc_x(hctx->ccid3hctx_s, |
159 | hctx->ccid3hctx_rtt, | |
160 | hctx->ccid3hctx_p); | |
1f2333ae ACM |
161 | hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_calc, |
162 | 2 * hctx->ccid3hctx_x_recv), | |
163 | (hctx->ccid3hctx_s / | |
164 | TFRC_MAX_BACK_OFF_TIME)); | |
b6ee3d4a ACM |
165 | } else { |
166 | struct timeval now; | |
167 | ||
b0e56780 | 168 | dccp_timestamp(sk, &now); |
b6ee3d4a ACM |
169 | if (timeval_delta(&now, &hctx->ccid3hctx_t_ld) >= |
170 | hctx->ccid3hctx_rtt) { | |
6b5e633a ACM |
171 | hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_recv, |
172 | hctx->ccid3hctx_x) * 2, | |
173 | usecs_div(hctx->ccid3hctx_s, | |
174 | hctx->ccid3hctx_rtt)); | |
b6ee3d4a ACM |
175 | hctx->ccid3hctx_t_ld = now; |
176 | } | |
7c657876 | 177 | } |
7c657876 ACM |
178 | } |
179 | ||
180 | static void ccid3_hc_tx_no_feedback_timer(unsigned long data) | |
181 | { | |
182 | struct sock *sk = (struct sock *)data; | |
7c657876 | 183 | unsigned long next_tmout = 0; |
59725dc2 | 184 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 ACM |
185 | |
186 | bh_lock_sock(sk); | |
187 | if (sock_owned_by_user(sk)) { | |
188 | /* Try again later. */ | |
189 | /* XXX: set some sensible MIB */ | |
1f2333ae ACM |
190 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, |
191 | jiffies + HZ / 5); | |
7c657876 ACM |
192 | goto out; |
193 | } | |
194 | ||
195 | ccid3_pr_debug("%s, sk=%p, state=%s\n", dccp_role(sk), sk, | |
196 | ccid3_tx_state_name(hctx->ccid3hctx_state)); | |
197 | ||
7c657876 ACM |
198 | switch (hctx->ccid3hctx_state) { |
199 | case TFRC_SSTATE_TERM: | |
200 | goto out; | |
201 | case TFRC_SSTATE_NO_FBACK: | |
202 | /* Halve send rate */ | |
203 | hctx->ccid3hctx_x /= 2; | |
6b5e633a ACM |
204 | if (hctx->ccid3hctx_x < (hctx->ccid3hctx_s / |
205 | TFRC_MAX_BACK_OFF_TIME)) | |
1f2333ae ACM |
206 | hctx->ccid3hctx_x = (hctx->ccid3hctx_s / |
207 | TFRC_MAX_BACK_OFF_TIME); | |
7c657876 | 208 | |
1f2333ae ACM |
209 | ccid3_pr_debug("%s, sk=%p, state=%s, updated tx rate to %d " |
210 | "bytes/s\n", | |
211 | dccp_role(sk), sk, | |
212 | ccid3_tx_state_name(hctx->ccid3hctx_state), | |
7c657876 | 213 | hctx->ccid3hctx_x); |
6b5e633a ACM |
214 | next_tmout = max_t(u32, 2 * usecs_div(hctx->ccid3hctx_s, |
215 | hctx->ccid3hctx_x), | |
1f2333ae | 216 | TFRC_INITIAL_TIMEOUT); |
1f2333ae ACM |
217 | /* |
218 | * FIXME - not sure above calculation is correct. See section | |
219 | * 5 of CCID3 11 should adjust tx_t_ipi and double that to | |
220 | * achieve it really | |
221 | */ | |
7c657876 ACM |
222 | break; |
223 | case TFRC_SSTATE_FBACK: | |
1f2333ae ACM |
224 | /* |
225 | * Check if IDLE since last timeout and recv rate is less than | |
226 | * 4 packets per RTT | |
227 | */ | |
1f2333ae | 228 | if (!hctx->ccid3hctx_idle || |
6b5e633a ACM |
229 | (hctx->ccid3hctx_x_recv >= |
230 | 4 * usecs_div(hctx->ccid3hctx_s, hctx->ccid3hctx_rtt))) { | |
1f2333ae ACM |
231 | ccid3_pr_debug("%s, sk=%p, state=%s, not idle\n", |
232 | dccp_role(sk), sk, | |
7c657876 ACM |
233 | ccid3_tx_state_name(hctx->ccid3hctx_state)); |
234 | /* Halve sending rate */ | |
235 | ||
236 | /* If (X_calc > 2 * X_recv) | |
237 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); | |
238 | * Else | |
239 | * X_recv = X_calc / 4; | |
240 | */ | |
1f2333ae ACM |
241 | BUG_ON(hctx->ccid3hctx_p >= TFRC_SMALLEST_P && |
242 | hctx->ccid3hctx_x_calc == 0); | |
7c657876 ACM |
243 | |
244 | /* check also if p is zero -> x_calc is infinity? */ | |
245 | if (hctx->ccid3hctx_p < TFRC_SMALLEST_P || | |
246 | hctx->ccid3hctx_x_calc > 2 * hctx->ccid3hctx_x_recv) | |
247 | hctx->ccid3hctx_x_recv = max_t(u32, hctx->ccid3hctx_x_recv / 2, | |
248 | hctx->ccid3hctx_s / (2 * TFRC_MAX_BACK_OFF_TIME)); | |
249 | else | |
250 | hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc / 4; | |
251 | ||
252 | /* Update sending rate */ | |
253 | ccid3_hc_tx_update_x(sk); | |
254 | } | |
6b5e633a ACM |
255 | /* |
256 | * Schedule no feedback timer to expire in | |
257 | * max(4 * R, 2 * s / X) | |
258 | */ | |
c68e64cf | 259 | next_tmout = max_t(u32, hctx->ccid3hctx_t_rto, |
6b5e633a ACM |
260 | 2 * usecs_div(hctx->ccid3hctx_s, |
261 | hctx->ccid3hctx_x)); | |
7c657876 ACM |
262 | break; |
263 | default: | |
264 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | |
265 | __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); | |
266 | dump_stack(); | |
267 | goto out; | |
268 | } | |
269 | ||
270 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | |
1f2333ae | 271 | jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout))); |
7c657876 ACM |
272 | hctx->ccid3hctx_idle = 1; |
273 | out: | |
274 | bh_unlock_sock(sk); | |
275 | sock_put(sk); | |
276 | } | |
277 | ||
27258ee5 ACM |
278 | static int ccid3_hc_tx_send_packet(struct sock *sk, |
279 | struct sk_buff *skb, int len) | |
7c657876 ACM |
280 | { |
281 | struct dccp_sock *dp = dccp_sk(sk); | |
59725dc2 | 282 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
8c60f3fa | 283 | struct dccp_tx_hist_entry *new_packet; |
7c657876 | 284 | struct timeval now; |
27258ee5 | 285 | long delay; |
7c657876 ACM |
286 | int rc = -ENOTCONN; |
287 | ||
59d203f9 | 288 | BUG_ON(hctx == NULL || hctx->ccid3hctx_state == TFRC_SSTATE_TERM); |
1f2333ae | 289 | |
59d203f9 | 290 | /* Check if pure ACK or Terminating*/ |
7c657876 | 291 | /* |
1f2333ae ACM |
292 | * XXX: We only call this function for DATA and DATAACK, on, these |
293 | * packets can have zero length, but why the comment about "pure ACK"? | |
7c657876 | 294 | */ |
59d203f9 | 295 | if (unlikely(len == 0)) |
7c657876 ACM |
296 | goto out; |
297 | ||
298 | /* See if last packet allocated was not sent */ | |
8c60f3fa ACM |
299 | new_packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist); |
300 | if (new_packet == NULL || new_packet->dccphtx_sent) { | |
1f2333ae ACM |
301 | new_packet = dccp_tx_hist_entry_new(ccid3_tx_hist, |
302 | SLAB_ATOMIC); | |
7c657876 ACM |
303 | |
304 | rc = -ENOBUFS; | |
59d203f9 ACM |
305 | if (unlikely(new_packet == NULL)) { |
306 | LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, not enough " | |
307 | "mem to add to history, send refused\n", | |
308 | __FUNCTION__, dccp_role(sk), sk); | |
7c657876 ACM |
309 | goto out; |
310 | } | |
311 | ||
8c60f3fa | 312 | dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, new_packet); |
7c657876 ACM |
313 | } |
314 | ||
b0e56780 | 315 | dccp_timestamp(sk, &now); |
7c657876 ACM |
316 | |
317 | switch (hctx->ccid3hctx_state) { | |
318 | case TFRC_SSTATE_NO_SENT: | |
7c657876 ACM |
319 | hctx->ccid3hctx_no_feedback_timer.function = ccid3_hc_tx_no_feedback_timer; |
320 | hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk; | |
1f2333ae ACM |
321 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, |
322 | jiffies + usecs_to_jiffies(TFRC_INITIAL_TIMEOUT)); | |
7c657876 ACM |
323 | hctx->ccid3hctx_last_win_count = 0; |
324 | hctx->ccid3hctx_t_last_win_count = now; | |
325 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); | |
d7e0fb98 | 326 | hctx->ccid3hctx_t_ipi = TFRC_INITIAL_IPI; |
7c657876 ACM |
327 | |
328 | /* Set nominal send time for initial packet */ | |
329 | hctx->ccid3hctx_t_nom = now; | |
b6ee3d4a ACM |
330 | timeval_add_usecs(&hctx->ccid3hctx_t_nom, |
331 | hctx->ccid3hctx_t_ipi); | |
7c657876 ACM |
332 | ccid3_calc_new_delta(hctx); |
333 | rc = 0; | |
334 | break; | |
335 | case TFRC_SSTATE_NO_FBACK: | |
336 | case TFRC_SSTATE_FBACK: | |
b6ee3d4a ACM |
337 | delay = (timeval_delta(&now, &hctx->ccid3hctx_t_nom) - |
338 | hctx->ccid3hctx_delta); | |
27258ee5 | 339 | delay /= -1000; |
7c657876 | 340 | /* divide by -1000 is to convert to ms and get sign right */ |
d6809c12 | 341 | rc = delay > 0 ? delay : 0; |
7c657876 ACM |
342 | break; |
343 | default: | |
344 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | |
345 | __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); | |
346 | dump_stack(); | |
347 | rc = -EINVAL; | |
348 | break; | |
349 | } | |
350 | ||
351 | /* Can we send? if so add options and add to packet history */ | |
507d37cf ACM |
352 | if (rc == 0) { |
353 | dp->dccps_hc_tx_insert_options = 1; | |
c1734376 | 354 | new_packet->dccphtx_ccval = |
8c60f3fa ACM |
355 | DCCP_SKB_CB(skb)->dccpd_ccval = |
356 | hctx->ccid3hctx_last_win_count; | |
507d37cf | 357 | } |
7c657876 ACM |
358 | out: |
359 | return rc; | |
360 | } | |
361 | ||
362 | static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, int len) | |
363 | { | |
59725dc2 ACM |
364 | const struct dccp_sock *dp = dccp_sk(sk); |
365 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); | |
7c657876 ACM |
366 | struct timeval now; |
367 | ||
59d203f9 | 368 | BUG_ON(hctx == NULL || hctx->ccid3hctx_state == TFRC_SSTATE_TERM); |
7c657876 | 369 | |
b0e56780 | 370 | dccp_timestamp(sk, &now); |
7c657876 ACM |
371 | |
372 | /* check if we have sent a data packet */ | |
373 | if (len > 0) { | |
374 | unsigned long quarter_rtt; | |
8c60f3fa | 375 | struct dccp_tx_hist_entry *packet; |
7c657876 | 376 | |
8c60f3fa | 377 | packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist); |
59d203f9 ACM |
378 | if (unlikely(packet == NULL)) { |
379 | LIMIT_NETDEBUG(KERN_WARNING "%s: packet doesn't " | |
380 | "exists in history!\n", __FUNCTION__); | |
7c657876 ACM |
381 | return; |
382 | } | |
59d203f9 ACM |
383 | if (unlikely(packet->dccphtx_sent)) { |
384 | LIMIT_NETDEBUG(KERN_WARNING "%s: no unsent packet in " | |
385 | "history!\n", __FUNCTION__); | |
7c657876 ACM |
386 | return; |
387 | } | |
8c60f3fa ACM |
388 | packet->dccphtx_tstamp = now; |
389 | packet->dccphtx_seqno = dp->dccps_gss; | |
7c657876 | 390 | /* |
1f2333ae ACM |
391 | * Check if win_count have changed |
392 | * Algorithm in "8.1. Window Counter Valuer" in | |
393 | * draft-ietf-dccp-ccid3-11.txt | |
7c657876 | 394 | */ |
6b5e633a ACM |
395 | quarter_rtt = timeval_delta(&now, &hctx->ccid3hctx_t_last_win_count); |
396 | if (likely(hctx->ccid3hctx_rtt > 8)) | |
397 | quarter_rtt /= hctx->ccid3hctx_rtt / 4; | |
398 | ||
7c657876 ACM |
399 | if (quarter_rtt > 0) { |
400 | hctx->ccid3hctx_t_last_win_count = now; | |
401 | hctx->ccid3hctx_last_win_count = (hctx->ccid3hctx_last_win_count + | |
402 | min_t(unsigned long, quarter_rtt, 5)) % 16; | |
1f2333ae ACM |
403 | ccid3_pr_debug("%s, sk=%p, window changed from " |
404 | "%u to %u!\n", | |
7c657876 | 405 | dccp_role(sk), sk, |
c1734376 | 406 | packet->dccphtx_ccval, |
7c657876 ACM |
407 | hctx->ccid3hctx_last_win_count); |
408 | } | |
1f2333ae | 409 | |
7c657876 | 410 | hctx->ccid3hctx_idle = 0; |
c1734376 | 411 | packet->dccphtx_rtt = hctx->ccid3hctx_rtt; |
8c60f3fa | 412 | packet->dccphtx_sent = 1; |
7c657876 ACM |
413 | } else |
414 | ccid3_pr_debug("%s, sk=%p, seqno=%llu NOT inserted!\n", | |
415 | dccp_role(sk), sk, dp->dccps_gss); | |
416 | ||
417 | switch (hctx->ccid3hctx_state) { | |
418 | case TFRC_SSTATE_NO_SENT: | |
419 | /* if first wasn't pure ack */ | |
420 | if (len != 0) | |
1f2333ae ACM |
421 | printk(KERN_CRIT "%s: %s, First packet sent is noted " |
422 | "as a data packet\n", | |
7c657876 ACM |
423 | __FUNCTION__, dccp_role(sk)); |
424 | return; | |
425 | case TFRC_SSTATE_NO_FBACK: | |
426 | case TFRC_SSTATE_FBACK: | |
427 | if (len > 0) { | |
428 | hctx->ccid3hctx_t_nom = now; | |
429 | ccid3_calc_new_t_ipi(hctx); | |
430 | ccid3_calc_new_delta(hctx); | |
b6ee3d4a ACM |
431 | timeval_add_usecs(&hctx->ccid3hctx_t_nom, |
432 | hctx->ccid3hctx_t_ipi); | |
7c657876 ACM |
433 | } |
434 | break; | |
435 | default: | |
436 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | |
437 | __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); | |
438 | dump_stack(); | |
439 | break; | |
440 | } | |
441 | } | |
442 | ||
443 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) | |
444 | { | |
59725dc2 ACM |
445 | const struct dccp_sock *dp = dccp_sk(sk); |
446 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); | |
7c657876 | 447 | struct ccid3_options_received *opt_recv; |
8c60f3fa | 448 | struct dccp_tx_hist_entry *packet; |
b0e56780 | 449 | struct timeval now; |
7c657876 | 450 | unsigned long next_tmout; |
1bc09869 | 451 | u32 t_elapsed; |
7c657876 ACM |
452 | u32 pinv; |
453 | u32 x_recv; | |
454 | u32 r_sample; | |
1f2333ae | 455 | |
59d203f9 | 456 | BUG_ON(hctx == NULL || hctx->ccid3hctx_state == TFRC_SSTATE_TERM); |
7c657876 ACM |
457 | |
458 | /* we are only interested in ACKs */ | |
459 | if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || | |
460 | DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) | |
461 | return; | |
462 | ||
463 | opt_recv = &hctx->ccid3hctx_options_received; | |
464 | ||
1a28599a | 465 | t_elapsed = dp->dccps_options_received.dccpor_elapsed_time * 10; |
7c657876 ACM |
466 | x_recv = opt_recv->ccid3or_receive_rate; |
467 | pinv = opt_recv->ccid3or_loss_event_rate; | |
468 | ||
469 | switch (hctx->ccid3hctx_state) { | |
470 | case TFRC_SSTATE_NO_SENT: | |
471 | /* FIXME: what to do here? */ | |
472 | return; | |
473 | case TFRC_SSTATE_NO_FBACK: | |
474 | case TFRC_SSTATE_FBACK: | |
475 | /* Calculate new round trip sample by | |
476 | * R_sample = (now - t_recvdata) - t_delay */ | |
477 | /* get t_recvdata from history */ | |
8c60f3fa ACM |
478 | packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist, |
479 | DCCP_SKB_CB(skb)->dccpd_ack_seq); | |
59d203f9 ACM |
480 | if (unlikely(packet == NULL)) { |
481 | LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, seqno " | |
482 | "%llu(%s) does't exist in history!\n", | |
483 | __FUNCTION__, dccp_role(sk), sk, | |
484 | (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq, | |
485 | dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type)); | |
7c657876 ACM |
486 | return; |
487 | } | |
488 | ||
489 | /* Update RTT */ | |
b0e56780 ACM |
490 | dccp_timestamp(sk, &now); |
491 | r_sample = timeval_delta(&now, &packet->dccphtx_tstamp); | |
1a28599a | 492 | if (unlikely(r_sample <= t_elapsed)) |
59d203f9 ACM |
493 | LIMIT_NETDEBUG(KERN_WARNING "%s: r_sample=%uus, " |
494 | "t_elapsed=%uus\n", | |
1a28599a ACM |
495 | __FUNCTION__, r_sample, t_elapsed); |
496 | else | |
497 | r_sample -= t_elapsed; | |
7c657876 ACM |
498 | |
499 | /* Update RTT estimate by | |
500 | * If (No feedback recv) | |
501 | * R = R_sample; | |
502 | * Else | |
503 | * R = q * R + (1 - q) * R_sample; | |
504 | * | |
505 | * q is a constant, RFC 3448 recomments 0.9 | |
506 | */ | |
507 | if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) { | |
508 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); | |
509 | hctx->ccid3hctx_rtt = r_sample; | |
510 | } else | |
1f2333ae ACM |
511 | hctx->ccid3hctx_rtt = (hctx->ccid3hctx_rtt * 9) / 10 + |
512 | r_sample / 10; | |
7c657876 | 513 | |
1f2333ae ACM |
514 | ccid3_pr_debug("%s, sk=%p, New RTT estimate=%uus, " |
515 | "r_sample=%us\n", dccp_role(sk), sk, | |
516 | hctx->ccid3hctx_rtt, r_sample); | |
7c657876 ACM |
517 | |
518 | /* Update timeout interval */ | |
c68e64cf ACM |
519 | hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt, |
520 | USEC_PER_SEC); | |
7c657876 ACM |
521 | |
522 | /* Update receive rate */ | |
1f2333ae | 523 | hctx->ccid3hctx_x_recv = x_recv;/* X_recv in bytes per sec */ |
7c657876 ACM |
524 | |
525 | /* Update loss event rate */ | |
526 | if (pinv == ~0 || pinv == 0) | |
527 | hctx->ccid3hctx_p = 0; | |
528 | else { | |
529 | hctx->ccid3hctx_p = 1000000 / pinv; | |
530 | ||
531 | if (hctx->ccid3hctx_p < TFRC_SMALLEST_P) { | |
532 | hctx->ccid3hctx_p = TFRC_SMALLEST_P; | |
1f2333ae ACM |
533 | ccid3_pr_debug("%s, sk=%p, Smallest p used!\n", |
534 | dccp_role(sk), sk); | |
7c657876 ACM |
535 | } |
536 | } | |
537 | ||
538 | /* unschedule no feedback timer */ | |
539 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); | |
540 | ||
541 | /* Update sending rate */ | |
542 | ccid3_hc_tx_update_x(sk); | |
543 | ||
544 | /* Update next send time */ | |
b6ee3d4a ACM |
545 | timeval_sub_usecs(&hctx->ccid3hctx_t_nom, |
546 | hctx->ccid3hctx_t_ipi); | |
7c657876 | 547 | ccid3_calc_new_t_ipi(hctx); |
b6ee3d4a ACM |
548 | timeval_add_usecs(&hctx->ccid3hctx_t_nom, |
549 | hctx->ccid3hctx_t_ipi); | |
7c657876 ACM |
550 | ccid3_calc_new_delta(hctx); |
551 | ||
552 | /* remove all packets older than the one acked from history */ | |
8c60f3fa ACM |
553 | dccp_tx_hist_purge_older(ccid3_tx_hist, |
554 | &hctx->ccid3hctx_hist, packet); | |
c530cfb1 ACM |
555 | /* |
556 | * As we have calculated new ipi, delta, t_nom it is possible that | |
557 | * we now can send a packet, so wake up dccp_wait_for_ccids. | |
558 | */ | |
559 | sk->sk_write_space(sk); | |
8c60f3fa | 560 | |
1f2333ae ACM |
561 | /* |
562 | * Schedule no feedback timer to expire in | |
563 | * max(4 * R, 2 * s / X) | |
564 | */ | |
c68e64cf | 565 | next_tmout = max(hctx->ccid3hctx_t_rto, |
6b5e633a ACM |
566 | 2 * usecs_div(hctx->ccid3hctx_s, |
567 | hctx->ccid3hctx_x)); | |
568 | ||
1f2333ae ACM |
569 | ccid3_pr_debug("%s, sk=%p, Scheduled no feedback timer to " |
570 | "expire in %lu jiffies (%luus)\n", | |
571 | dccp_role(sk), sk, | |
572 | usecs_to_jiffies(next_tmout), next_tmout); | |
7c657876 ACM |
573 | |
574 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | |
1f2333ae | 575 | jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout))); |
7c657876 ACM |
576 | |
577 | /* set idle flag */ | |
578 | hctx->ccid3hctx_idle = 1; | |
579 | break; | |
580 | default: | |
581 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | |
582 | __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); | |
583 | dump_stack(); | |
584 | break; | |
585 | } | |
586 | } | |
587 | ||
588 | static void ccid3_hc_tx_insert_options(struct sock *sk, struct sk_buff *skb) | |
589 | { | |
59d203f9 | 590 | const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 | 591 | |
59d203f9 ACM |
592 | BUG_ON(hctx == NULL); |
593 | ||
594 | if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) | |
7c657876 ACM |
595 | return; |
596 | ||
597 | DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; | |
598 | } | |
599 | ||
600 | static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, | |
1f2333ae ACM |
601 | unsigned char len, u16 idx, |
602 | unsigned char *value) | |
7c657876 ACM |
603 | { |
604 | int rc = 0; | |
59725dc2 ACM |
605 | const struct dccp_sock *dp = dccp_sk(sk); |
606 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); | |
7c657876 ACM |
607 | struct ccid3_options_received *opt_recv; |
608 | ||
59d203f9 | 609 | BUG_ON(hctx == NULL); |
7c657876 ACM |
610 | |
611 | opt_recv = &hctx->ccid3hctx_options_received; | |
612 | ||
613 | if (opt_recv->ccid3or_seqno != dp->dccps_gsr) { | |
614 | opt_recv->ccid3or_seqno = dp->dccps_gsr; | |
615 | opt_recv->ccid3or_loss_event_rate = ~0; | |
616 | opt_recv->ccid3or_loss_intervals_idx = 0; | |
617 | opt_recv->ccid3or_loss_intervals_len = 0; | |
618 | opt_recv->ccid3or_receive_rate = 0; | |
619 | } | |
620 | ||
621 | switch (option) { | |
622 | case TFRC_OPT_LOSS_EVENT_RATE: | |
59d203f9 ACM |
623 | if (unlikely(len != 4)) { |
624 | LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, invalid " | |
625 | "len for TFRC_OPT_LOSS_EVENT_RATE\n", | |
626 | __FUNCTION__, dccp_role(sk), sk); | |
7c657876 ACM |
627 | rc = -EINVAL; |
628 | } else { | |
629 | opt_recv->ccid3or_loss_event_rate = ntohl(*(u32 *)value); | |
630 | ccid3_pr_debug("%s, sk=%p, LOSS_EVENT_RATE=%u\n", | |
631 | dccp_role(sk), sk, | |
632 | opt_recv->ccid3or_loss_event_rate); | |
633 | } | |
634 | break; | |
635 | case TFRC_OPT_LOSS_INTERVALS: | |
636 | opt_recv->ccid3or_loss_intervals_idx = idx; | |
637 | opt_recv->ccid3or_loss_intervals_len = len; | |
638 | ccid3_pr_debug("%s, sk=%p, LOSS_INTERVALS=(%u, %u)\n", | |
639 | dccp_role(sk), sk, | |
640 | opt_recv->ccid3or_loss_intervals_idx, | |
641 | opt_recv->ccid3or_loss_intervals_len); | |
642 | break; | |
643 | case TFRC_OPT_RECEIVE_RATE: | |
59d203f9 ACM |
644 | if (unlikely(len != 4)) { |
645 | LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, invalid " | |
646 | "len for TFRC_OPT_RECEIVE_RATE\n", | |
647 | __FUNCTION__, dccp_role(sk), sk); | |
7c657876 ACM |
648 | rc = -EINVAL; |
649 | } else { | |
650 | opt_recv->ccid3or_receive_rate = ntohl(*(u32 *)value); | |
651 | ccid3_pr_debug("%s, sk=%p, RECEIVE_RATE=%u\n", | |
652 | dccp_role(sk), sk, | |
653 | opt_recv->ccid3or_receive_rate); | |
654 | } | |
655 | break; | |
656 | } | |
657 | ||
658 | return rc; | |
659 | } | |
660 | ||
661 | static int ccid3_hc_tx_init(struct sock *sk) | |
662 | { | |
663 | struct dccp_sock *dp = dccp_sk(sk); | |
664 | struct ccid3_hc_tx_sock *hctx; | |
665 | ||
59725dc2 ACM |
666 | dp->dccps_hc_tx_ccid_private = kmalloc(sizeof(*hctx), gfp_any()); |
667 | if (dp->dccps_hc_tx_ccid_private == NULL) | |
7c657876 ACM |
668 | return -ENOMEM; |
669 | ||
59725dc2 | 670 | hctx = ccid3_hc_tx_sk(sk); |
7c657876 ACM |
671 | memset(hctx, 0, sizeof(*hctx)); |
672 | ||
a84ffe43 ACM |
673 | if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE && |
674 | dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE) | |
675 | hctx->ccid3hctx_s = dp->dccps_packet_size; | |
7c657876 ACM |
676 | else |
677 | hctx->ccid3hctx_s = TFRC_STD_PACKET_SIZE; | |
678 | ||
1f2333ae ACM |
679 | /* Set transmission rate to 1 packet per second */ |
680 | hctx->ccid3hctx_x = hctx->ccid3hctx_s; | |
c68e64cf | 681 | hctx->ccid3hctx_t_rto = USEC_PER_SEC; |
7c657876 ACM |
682 | hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT; |
683 | INIT_LIST_HEAD(&hctx->ccid3hctx_hist); | |
684 | init_timer(&hctx->ccid3hctx_no_feedback_timer); | |
685 | ||
686 | return 0; | |
687 | } | |
688 | ||
689 | static void ccid3_hc_tx_exit(struct sock *sk) | |
690 | { | |
691 | struct dccp_sock *dp = dccp_sk(sk); | |
59725dc2 | 692 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 | 693 | |
7c657876 ACM |
694 | BUG_ON(hctx == NULL); |
695 | ||
696 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM); | |
697 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); | |
698 | ||
699 | /* Empty packet history */ | |
8c60f3fa | 700 | dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist); |
7c657876 ACM |
701 | |
702 | kfree(dp->dccps_hc_tx_ccid_private); | |
703 | dp->dccps_hc_tx_ccid_private = NULL; | |
704 | } | |
705 | ||
706 | /* | |
707 | * RX Half Connection methods | |
708 | */ | |
709 | ||
710 | /* TFRC receiver states */ | |
711 | enum ccid3_hc_rx_states { | |
712 | TFRC_RSTATE_NO_DATA = 1, | |
713 | TFRC_RSTATE_DATA, | |
714 | TFRC_RSTATE_TERM = 127, | |
715 | }; | |
716 | ||
717 | #ifdef CCID3_DEBUG | |
718 | static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) | |
719 | { | |
720 | static char *ccid3_rx_state_names[] = { | |
721 | [TFRC_RSTATE_NO_DATA] = "NO_DATA", | |
722 | [TFRC_RSTATE_DATA] = "DATA", | |
723 | [TFRC_RSTATE_TERM] = "TERM", | |
724 | }; | |
725 | ||
726 | return ccid3_rx_state_names[state]; | |
727 | } | |
728 | #endif | |
729 | ||
1f2333ae ACM |
730 | static inline void ccid3_hc_rx_set_state(struct sock *sk, |
731 | enum ccid3_hc_rx_states state) | |
7c657876 | 732 | { |
59725dc2 | 733 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 ACM |
734 | enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state; |
735 | ||
736 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | |
1f2333ae ACM |
737 | dccp_role(sk), sk, ccid3_rx_state_name(oldstate), |
738 | ccid3_rx_state_name(state)); | |
7c657876 ACM |
739 | WARN_ON(state == oldstate); |
740 | hcrx->ccid3hcrx_state = state; | |
741 | } | |
742 | ||
7c657876 ACM |
743 | static void ccid3_hc_rx_send_feedback(struct sock *sk) |
744 | { | |
59725dc2 | 745 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 | 746 | struct dccp_sock *dp = dccp_sk(sk); |
8c60f3fa | 747 | struct dccp_rx_hist_entry *packet; |
b6ee3d4a | 748 | struct timeval now; |
7c657876 ACM |
749 | |
750 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | |
751 | ||
b0e56780 | 752 | dccp_timestamp(sk, &now); |
b6ee3d4a | 753 | |
7c657876 ACM |
754 | switch (hcrx->ccid3hcrx_state) { |
755 | case TFRC_RSTATE_NO_DATA: | |
756 | hcrx->ccid3hcrx_x_recv = 0; | |
757 | break; | |
758 | case TFRC_RSTATE_DATA: { | |
b6ee3d4a ACM |
759 | const u32 delta = timeval_delta(&now, |
760 | &hcrx->ccid3hcrx_tstamp_last_feedback); | |
27ae543e ACM |
761 | hcrx->ccid3hcrx_x_recv = usecs_div(hcrx->ccid3hcrx_bytes_recv, |
762 | delta); | |
7c657876 ACM |
763 | } |
764 | break; | |
765 | default: | |
766 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | |
767 | __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state); | |
768 | dump_stack(); | |
769 | return; | |
770 | } | |
771 | ||
8c60f3fa | 772 | packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist); |
59d203f9 ACM |
773 | if (unlikely(packet == NULL)) { |
774 | LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, no data packet " | |
775 | "in history!\n", | |
776 | __FUNCTION__, dccp_role(sk), sk); | |
7c657876 ACM |
777 | return; |
778 | } | |
779 | ||
b6ee3d4a | 780 | hcrx->ccid3hcrx_tstamp_last_feedback = now; |
c1734376 | 781 | hcrx->ccid3hcrx_last_counter = packet->dccphrx_ccval; |
8c60f3fa | 782 | hcrx->ccid3hcrx_seqno_last_counter = packet->dccphrx_seqno; |
7c657876 ACM |
783 | hcrx->ccid3hcrx_bytes_recv = 0; |
784 | ||
785 | /* Convert to multiples of 10us */ | |
b6ee3d4a ACM |
786 | hcrx->ccid3hcrx_elapsed_time = |
787 | timeval_delta(&now, &packet->dccphrx_tstamp) / 10; | |
7c657876 ACM |
788 | if (hcrx->ccid3hcrx_p == 0) |
789 | hcrx->ccid3hcrx_pinv = ~0; | |
790 | else | |
791 | hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p; | |
507d37cf | 792 | dp->dccps_hc_rx_insert_options = 1; |
7c657876 ACM |
793 | dccp_send_ack(sk); |
794 | } | |
795 | ||
796 | static void ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) | |
797 | { | |
59d203f9 | 798 | const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
4fded33b | 799 | u32 x_recv, pinv; |
7c657876 | 800 | |
59d203f9 ACM |
801 | BUG_ON(hcrx == NULL); |
802 | ||
803 | if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) | |
7c657876 ACM |
804 | return; |
805 | ||
7c657876 | 806 | DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_last_counter; |
4fded33b ACM |
807 | |
808 | if (dccp_packet_without_ack(skb)) | |
809 | return; | |
810 | ||
811 | if (hcrx->ccid3hcrx_elapsed_time != 0) | |
812 | dccp_insert_option_elapsed_time(sk, skb, | |
813 | hcrx->ccid3hcrx_elapsed_time); | |
814 | dccp_insert_option_timestamp(sk, skb); | |
815 | x_recv = htonl(hcrx->ccid3hcrx_x_recv); | |
816 | pinv = htonl(hcrx->ccid3hcrx_pinv); | |
817 | dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE, | |
818 | &pinv, sizeof(pinv)); | |
819 | dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE, | |
820 | &x_recv, sizeof(x_recv)); | |
7c657876 ACM |
821 | } |
822 | ||
7c657876 ACM |
823 | /* calculate first loss interval |
824 | * | |
825 | * returns estimated loss interval in usecs */ | |
826 | ||
827 | static u32 ccid3_hc_rx_calc_first_li(struct sock *sk) | |
828 | { | |
59725dc2 | 829 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
8c60f3fa | 830 | struct dccp_rx_hist_entry *entry, *next, *tail = NULL; |
7c657876 | 831 | u32 rtt, delta, x_recv, fval, p, tmp2; |
b6ee3d4a | 832 | struct timeval tstamp = { 0, }; |
7c657876 ACM |
833 | int interval = 0; |
834 | int win_count = 0; | |
835 | int step = 0; | |
836 | u64 tmp1; | |
837 | ||
8c60f3fa ACM |
838 | list_for_each_entry_safe(entry, next, &hcrx->ccid3hcrx_hist, |
839 | dccphrx_node) { | |
840 | if (dccp_rx_hist_entry_data_packet(entry)) { | |
7c657876 ACM |
841 | tail = entry; |
842 | ||
843 | switch (step) { | |
844 | case 0: | |
8c60f3fa | 845 | tstamp = entry->dccphrx_tstamp; |
c1734376 | 846 | win_count = entry->dccphrx_ccval; |
7c657876 ACM |
847 | step = 1; |
848 | break; | |
849 | case 1: | |
c1734376 | 850 | interval = win_count - entry->dccphrx_ccval; |
7c657876 ACM |
851 | if (interval < 0) |
852 | interval += TFRC_WIN_COUNT_LIMIT; | |
853 | if (interval > 4) | |
854 | goto found; | |
855 | break; | |
856 | } | |
857 | } | |
858 | } | |
859 | ||
59d203f9 ACM |
860 | if (unlikely(step == 0)) { |
861 | LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, packet history " | |
862 | "contains no data packets!\n", | |
863 | __FUNCTION__, dccp_role(sk), sk); | |
7c657876 ACM |
864 | return ~0; |
865 | } | |
866 | ||
59d203f9 ACM |
867 | if (unlikely(interval == 0)) { |
868 | LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, Could not find a " | |
869 | "win_count interval > 0. Defaulting to 1\n", | |
870 | __FUNCTION__, dccp_role(sk), sk); | |
7c657876 ACM |
871 | interval = 1; |
872 | } | |
873 | found: | |
b6ee3d4a | 874 | rtt = timeval_delta(&tstamp, &tail->dccphrx_tstamp) * 4 / interval; |
7c657876 ACM |
875 | ccid3_pr_debug("%s, sk=%p, approximated RTT to %uus\n", |
876 | dccp_role(sk), sk, rtt); | |
877 | if (rtt == 0) | |
878 | rtt = 1; | |
879 | ||
b0e56780 ACM |
880 | dccp_timestamp(sk, &tstamp); |
881 | delta = timeval_delta(&tstamp, &hcrx->ccid3hcrx_tstamp_last_feedback); | |
882 | x_recv = usecs_div(hcrx->ccid3hcrx_bytes_recv, delta); | |
7c657876 ACM |
883 | |
884 | tmp1 = (u64)x_recv * (u64)rtt; | |
885 | do_div(tmp1,10000000); | |
886 | tmp2 = (u32)tmp1; | |
887 | fval = (hcrx->ccid3hcrx_s * 100000) / tmp2; | |
888 | /* do not alter order above or you will get overflow on 32 bit */ | |
36729c1a | 889 | p = tfrc_calc_x_reverse_lookup(fval); |
1f2333ae ACM |
890 | ccid3_pr_debug("%s, sk=%p, receive rate=%u bytes/s, implied " |
891 | "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); | |
7c657876 ACM |
892 | |
893 | if (p == 0) | |
894 | return ~0; | |
895 | else | |
896 | return 1000000 / p; | |
897 | } | |
898 | ||
899 | static void ccid3_hc_rx_update_li(struct sock *sk, u64 seq_loss, u8 win_loss) | |
900 | { | |
59725dc2 | 901 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 | 902 | |
ae6706f0 ACM |
903 | if (seq_loss != DCCP_MAX_SEQNO + 1 && |
904 | list_empty(&hcrx->ccid3hcrx_li_hist)) { | |
905 | struct dccp_li_hist_entry *li_tail; | |
7c657876 | 906 | |
ae6706f0 ACM |
907 | li_tail = dccp_li_hist_interval_new(ccid3_li_hist, |
908 | &hcrx->ccid3hcrx_li_hist, | |
909 | seq_loss, win_loss); | |
910 | if (li_tail == NULL) | |
911 | return; | |
912 | li_tail->dccplih_interval = ccid3_hc_rx_calc_first_li(sk); | |
59d203f9 ACM |
913 | } else |
914 | LIMIT_NETDEBUG(KERN_WARNING "%s: FIXME: find end of " | |
915 | "interval\n", __FUNCTION__); | |
7c657876 ACM |
916 | } |
917 | ||
918 | static void ccid3_hc_rx_detect_loss(struct sock *sk) | |
919 | { | |
59725dc2 | 920 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
29e4f8b3 ACM |
921 | u8 win_loss; |
922 | const u64 seq_loss = dccp_rx_hist_detect_loss(&hcrx->ccid3hcrx_hist, | |
923 | &hcrx->ccid3hcrx_li_hist, | |
924 | &win_loss); | |
7c657876 | 925 | |
7c657876 ACM |
926 | ccid3_hc_rx_update_li(sk, seq_loss, win_loss); |
927 | } | |
928 | ||
7c657876 ACM |
929 | static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) |
930 | { | |
59725dc2 | 931 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
4fded33b | 932 | const struct dccp_options_received *opt_recv; |
8c60f3fa | 933 | struct dccp_rx_hist_entry *packet; |
7c657876 ACM |
934 | struct timeval now; |
935 | u8 win_count; | |
b3a3077d | 936 | u32 p_prev, r_sample, t_elapsed; |
7c657876 | 937 | int ins; |
1f2333ae | 938 | |
59d203f9 ACM |
939 | BUG_ON(hcrx == NULL || |
940 | !(hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA || | |
7c657876 ACM |
941 | hcrx->ccid3hcrx_state == TFRC_RSTATE_DATA)); |
942 | ||
59725dc2 | 943 | opt_recv = &dccp_sk(sk)->dccps_options_received; |
4fded33b | 944 | |
7c657876 ACM |
945 | switch (DCCP_SKB_CB(skb)->dccpd_type) { |
946 | case DCCP_PKT_ACK: | |
947 | if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) | |
948 | return; | |
949 | case DCCP_PKT_DATAACK: | |
4fded33b | 950 | if (opt_recv->dccpor_timestamp_echo == 0) |
7c657876 ACM |
951 | break; |
952 | p_prev = hcrx->ccid3hcrx_rtt; | |
b0e56780 | 953 | dccp_timestamp(sk, &now); |
b3a3077d ACM |
954 | timeval_sub_usecs(&now, opt_recv->dccpor_timestamp_echo * 10); |
955 | r_sample = timeval_usecs(&now); | |
956 | t_elapsed = opt_recv->dccpor_elapsed_time * 10; | |
957 | ||
958 | if (unlikely(r_sample <= t_elapsed)) | |
59d203f9 ACM |
959 | LIMIT_NETDEBUG(KERN_WARNING "%s: r_sample=%uus, " |
960 | "t_elapsed=%uus\n", | |
b3a3077d ACM |
961 | __FUNCTION__, r_sample, t_elapsed); |
962 | else | |
963 | r_sample -= t_elapsed; | |
964 | ||
965 | if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) | |
966 | hcrx->ccid3hcrx_rtt = r_sample; | |
967 | else | |
968 | hcrx->ccid3hcrx_rtt = (hcrx->ccid3hcrx_rtt * 9) / 10 + | |
969 | r_sample / 10; | |
970 | ||
7c657876 | 971 | if (p_prev != hcrx->ccid3hcrx_rtt) |
4fded33b ACM |
972 | ccid3_pr_debug("%s, New RTT=%luus, elapsed time=%u\n", |
973 | dccp_role(sk), hcrx->ccid3hcrx_rtt, | |
974 | opt_recv->dccpor_elapsed_time); | |
7c657876 ACM |
975 | break; |
976 | case DCCP_PKT_DATA: | |
977 | break; | |
59d203f9 | 978 | default: /* We're not interested in other packet types, move along */ |
7c657876 ACM |
979 | return; |
980 | } | |
981 | ||
b0e56780 | 982 | packet = dccp_rx_hist_entry_new(ccid3_rx_hist, sk, opt_recv->dccpor_ndp, |
8c60f3fa | 983 | skb, SLAB_ATOMIC); |
59d203f9 ACM |
984 | if (unlikely(packet == NULL)) { |
985 | LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, Not enough mem to " | |
986 | "add rx packet to history, consider it lost!\n", | |
987 | __FUNCTION__, dccp_role(sk), sk); | |
7c657876 ACM |
988 | return; |
989 | } | |
990 | ||
c1734376 | 991 | win_count = packet->dccphrx_ccval; |
7c657876 | 992 | |
072ab6c6 ACM |
993 | ins = dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist, |
994 | &hcrx->ccid3hcrx_li_hist, packet); | |
7c657876 ACM |
995 | |
996 | if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK) | |
997 | return; | |
998 | ||
999 | switch (hcrx->ccid3hcrx_state) { | |
1000 | case TFRC_RSTATE_NO_DATA: | |
1f2333ae ACM |
1001 | ccid3_pr_debug("%s, sk=%p(%s), skb=%p, sending initial " |
1002 | "feedback\n", | |
1003 | dccp_role(sk), sk, | |
1004 | dccp_state_name(sk->sk_state), skb); | |
7c657876 ACM |
1005 | ccid3_hc_rx_send_feedback(sk); |
1006 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); | |
1007 | return; | |
1008 | case TFRC_RSTATE_DATA: | |
1f2333ae ACM |
1009 | hcrx->ccid3hcrx_bytes_recv += skb->len - |
1010 | dccp_hdr(skb)->dccph_doff * 4; | |
b6ee3d4a ACM |
1011 | if (ins != 0) |
1012 | break; | |
1013 | ||
b0e56780 | 1014 | dccp_timestamp(sk, &now); |
b6ee3d4a ACM |
1015 | if (timeval_delta(&now, &hcrx->ccid3hcrx_tstamp_last_ack) >= |
1016 | hcrx->ccid3hcrx_rtt) { | |
1017 | hcrx->ccid3hcrx_tstamp_last_ack = now; | |
1018 | ccid3_hc_rx_send_feedback(sk); | |
7c657876 | 1019 | } |
b6ee3d4a | 1020 | return; |
7c657876 ACM |
1021 | default: |
1022 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | |
1023 | __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state); | |
1024 | dump_stack(); | |
1025 | return; | |
1026 | } | |
1027 | ||
1028 | /* Dealing with packet loss */ | |
4fded33b ACM |
1029 | ccid3_pr_debug("%s, sk=%p(%s), data loss! Reacting...\n", |
1030 | dccp_role(sk), sk, dccp_state_name(sk->sk_state)); | |
7c657876 ACM |
1031 | |
1032 | ccid3_hc_rx_detect_loss(sk); | |
1033 | p_prev = hcrx->ccid3hcrx_p; | |
1034 | ||
1035 | /* Calculate loss event rate */ | |
ae6706f0 | 1036 | if (!list_empty(&hcrx->ccid3hcrx_li_hist)) |
7c657876 | 1037 | /* Scaling up by 1000000 as fixed decimal */ |
ae6706f0 | 1038 | hcrx->ccid3hcrx_p = 1000000 / dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist); |
7c657876 ACM |
1039 | |
1040 | if (hcrx->ccid3hcrx_p > p_prev) { | |
1041 | ccid3_hc_rx_send_feedback(sk); | |
1042 | return; | |
1043 | } | |
1044 | } | |
1045 | ||
1046 | static int ccid3_hc_rx_init(struct sock *sk) | |
1047 | { | |
1048 | struct dccp_sock *dp = dccp_sk(sk); | |
1049 | struct ccid3_hc_rx_sock *hcrx; | |
1050 | ||
1051 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | |
1052 | ||
59725dc2 ACM |
1053 | dp->dccps_hc_rx_ccid_private = kmalloc(sizeof(*hcrx), gfp_any()); |
1054 | if (dp->dccps_hc_rx_ccid_private == NULL) | |
7c657876 ACM |
1055 | return -ENOMEM; |
1056 | ||
59725dc2 | 1057 | hcrx = ccid3_hc_rx_sk(sk); |
7c657876 ACM |
1058 | memset(hcrx, 0, sizeof(*hcrx)); |
1059 | ||
a84ffe43 ACM |
1060 | if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE && |
1061 | dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE) | |
1062 | hcrx->ccid3hcrx_s = dp->dccps_packet_size; | |
7c657876 ACM |
1063 | else |
1064 | hcrx->ccid3hcrx_s = TFRC_STD_PACKET_SIZE; | |
1065 | ||
1066 | hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA; | |
1067 | INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist); | |
ae6706f0 | 1068 | INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist); |
b0e56780 | 1069 | dccp_timestamp(sk, &hcrx->ccid3hcrx_tstamp_last_ack); |
954ee31f ACM |
1070 | hcrx->ccid3hcrx_tstamp_last_feedback = hcrx->ccid3hcrx_tstamp_last_ack; |
1071 | hcrx->ccid3hcrx_rtt = 5000; /* XXX 5ms for now... */ | |
7c657876 ACM |
1072 | return 0; |
1073 | } | |
1074 | ||
1075 | static void ccid3_hc_rx_exit(struct sock *sk) | |
1076 | { | |
59725dc2 | 1077 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 | 1078 | struct dccp_sock *dp = dccp_sk(sk); |
7c657876 | 1079 | |
59d203f9 | 1080 | BUG_ON(hcrx == NULL); |
7c657876 ACM |
1081 | |
1082 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM); | |
1083 | ||
1084 | /* Empty packet history */ | |
8c60f3fa | 1085 | dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist); |
7c657876 ACM |
1086 | |
1087 | /* Empty loss interval history */ | |
ae6706f0 | 1088 | dccp_li_hist_purge(ccid3_li_hist, &hcrx->ccid3hcrx_li_hist); |
7c657876 ACM |
1089 | |
1090 | kfree(dp->dccps_hc_rx_ccid_private); | |
1091 | dp->dccps_hc_rx_ccid_private = NULL; | |
1092 | } | |
1093 | ||
2babe1f6 ACM |
1094 | static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) |
1095 | { | |
59725dc2 | 1096 | const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
2babe1f6 | 1097 | |
59d203f9 | 1098 | BUG_ON(hcrx == NULL); |
2babe1f6 ACM |
1099 | |
1100 | info->tcpi_ca_state = hcrx->ccid3hcrx_state; | |
1101 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; | |
1102 | info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt; | |
1103 | } | |
1104 | ||
1105 | static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) | |
1106 | { | |
59725dc2 | 1107 | const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
2babe1f6 | 1108 | |
59d203f9 | 1109 | BUG_ON(hctx == NULL); |
2babe1f6 ACM |
1110 | |
1111 | info->tcpi_rto = hctx->ccid3hctx_t_rto; | |
1112 | info->tcpi_rtt = hctx->ccid3hctx_rtt; | |
1113 | } | |
1114 | ||
7c657876 ACM |
1115 | static struct ccid ccid3 = { |
1116 | .ccid_id = 3, | |
1117 | .ccid_name = "ccid3", | |
1118 | .ccid_owner = THIS_MODULE, | |
1119 | .ccid_init = ccid3_init, | |
1120 | .ccid_exit = ccid3_exit, | |
1121 | .ccid_hc_tx_init = ccid3_hc_tx_init, | |
1122 | .ccid_hc_tx_exit = ccid3_hc_tx_exit, | |
1123 | .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, | |
1124 | .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, | |
1125 | .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, | |
1126 | .ccid_hc_tx_insert_options = ccid3_hc_tx_insert_options, | |
1127 | .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, | |
1128 | .ccid_hc_rx_init = ccid3_hc_rx_init, | |
1129 | .ccid_hc_rx_exit = ccid3_hc_rx_exit, | |
1130 | .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, | |
1131 | .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, | |
2babe1f6 ACM |
1132 | .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, |
1133 | .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, | |
7c657876 ACM |
1134 | }; |
1135 | ||
1136 | module_param(ccid3_debug, int, 0444); | |
1137 | MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); | |
1138 | ||
1139 | static __init int ccid3_module_init(void) | |
1140 | { | |
8c60f3fa | 1141 | int rc = -ENOBUFS; |
7c657876 | 1142 | |
8c60f3fa ACM |
1143 | ccid3_rx_hist = dccp_rx_hist_new("ccid3"); |
1144 | if (ccid3_rx_hist == NULL) | |
7c657876 ACM |
1145 | goto out; |
1146 | ||
8c60f3fa ACM |
1147 | ccid3_tx_hist = dccp_tx_hist_new("ccid3"); |
1148 | if (ccid3_tx_hist == NULL) | |
1149 | goto out_free_rx; | |
7c657876 | 1150 | |
ae6706f0 ACM |
1151 | ccid3_li_hist = dccp_li_hist_new("ccid3"); |
1152 | if (ccid3_li_hist == NULL) | |
8c60f3fa | 1153 | goto out_free_tx; |
7c657876 ACM |
1154 | |
1155 | rc = ccid_register(&ccid3); | |
1156 | if (rc != 0) | |
1157 | goto out_free_loss_interval_history; | |
7c657876 ACM |
1158 | out: |
1159 | return rc; | |
8c60f3fa | 1160 | |
7c657876 | 1161 | out_free_loss_interval_history: |
ae6706f0 ACM |
1162 | dccp_li_hist_delete(ccid3_li_hist); |
1163 | ccid3_li_hist = NULL; | |
8c60f3fa ACM |
1164 | out_free_tx: |
1165 | dccp_tx_hist_delete(ccid3_tx_hist); | |
1166 | ccid3_tx_hist = NULL; | |
1167 | out_free_rx: | |
1168 | dccp_rx_hist_delete(ccid3_rx_hist); | |
1169 | ccid3_rx_hist = NULL; | |
7c657876 ACM |
1170 | goto out; |
1171 | } | |
1172 | module_init(ccid3_module_init); | |
1173 | ||
1174 | static __exit void ccid3_module_exit(void) | |
1175 | { | |
725ba8ee ACM |
1176 | #ifdef CONFIG_IP_DCCP_UNLOAD_HACK |
1177 | /* | |
1178 | * Hack to use while developing, so that we get rid of the control | |
1179 | * sock, that is what keeps a refcount on dccp.ko -acme | |
1180 | */ | |
1181 | extern void dccp_ctl_sock_exit(void); | |
1182 | ||
1183 | dccp_ctl_sock_exit(); | |
1184 | #endif | |
7c657876 ACM |
1185 | ccid_unregister(&ccid3); |
1186 | ||
8c60f3fa ACM |
1187 | if (ccid3_tx_hist != NULL) { |
1188 | dccp_tx_hist_delete(ccid3_tx_hist); | |
1189 | ccid3_tx_hist = NULL; | |
7c657876 | 1190 | } |
8c60f3fa ACM |
1191 | if (ccid3_rx_hist != NULL) { |
1192 | dccp_rx_hist_delete(ccid3_rx_hist); | |
1193 | ccid3_rx_hist = NULL; | |
7c657876 | 1194 | } |
ae6706f0 ACM |
1195 | if (ccid3_li_hist != NULL) { |
1196 | dccp_li_hist_delete(ccid3_li_hist); | |
1197 | ccid3_li_hist = NULL; | |
7c657876 ACM |
1198 | } |
1199 | } | |
1200 | module_exit(ccid3_module_exit); | |
1201 | ||
1f2333ae ACM |
1202 | MODULE_AUTHOR("Ian McDonald <iam4@cs.waikato.ac.nz>, " |
1203 | "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); | |
7c657876 ACM |
1204 | MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); |
1205 | MODULE_LICENSE("GPL"); | |
1206 | MODULE_ALIAS("net-dccp-ccid-3"); |