Commit | Line | Data |
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7c657876 ACM |
1 | /* |
2 | * net/dccp/ccids/ccid3.c | |
3 | * | |
b2f41ff4 IM |
4 | * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. |
5 | * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.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 | */ | |
7c657876 ACM |
36 | #include "../ccid.h" |
37 | #include "../dccp.h" | |
4524b259 | 38 | #include "lib/packet_history.h" |
ae6706f0 | 39 | #include "lib/loss_interval.h" |
36729c1a | 40 | #include "lib/tfrc.h" |
7c657876 ACM |
41 | #include "ccid3.h" |
42 | ||
56724aa4 GR |
43 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
44 | static int ccid3_debug; | |
45 | #define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a) | |
7c657876 ACM |
46 | #else |
47 | #define ccid3_pr_debug(format, a...) | |
48 | #endif | |
49 | ||
a1d3a355 ACM |
50 | static struct dccp_tx_hist *ccid3_tx_hist; |
51 | static struct dccp_rx_hist *ccid3_rx_hist; | |
7c657876 | 52 | |
9bf17475 GR |
53 | /* |
54 | * Transmitter Half-Connection Routines | |
55 | */ | |
56724aa4 | 56 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
7c657876 ACM |
57 | static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) |
58 | { | |
59 | static char *ccid3_state_names[] = { | |
60 | [TFRC_SSTATE_NO_SENT] = "NO_SENT", | |
61 | [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", | |
62 | [TFRC_SSTATE_FBACK] = "FBACK", | |
63 | [TFRC_SSTATE_TERM] = "TERM", | |
64 | }; | |
65 | ||
66 | return ccid3_state_names[state]; | |
67 | } | |
68 | #endif | |
69 | ||
c25a18ba ACM |
70 | static void ccid3_hc_tx_set_state(struct sock *sk, |
71 | enum ccid3_hc_tx_states state) | |
7c657876 | 72 | { |
59725dc2 | 73 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 ACM |
74 | enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state; |
75 | ||
76 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | |
1f2333ae ACM |
77 | dccp_role(sk), sk, ccid3_tx_state_name(oldstate), |
78 | ccid3_tx_state_name(state)); | |
7c657876 ACM |
79 | WARN_ON(state == oldstate); |
80 | hctx->ccid3hctx_state = state; | |
81 | } | |
82 | ||
a21f9f96 GR |
83 | /* |
84 | * Compute the initial sending rate X_init according to RFC 3390: | |
85 | * w_init = min(4 * MSS, max(2 * MSS, 4380 bytes)) | |
86 | * X_init = w_init / RTT | |
87 | * For consistency with other parts of the code, X_init is scaled by 2^6. | |
88 | */ | |
89 | static inline u64 rfc3390_initial_rate(struct sock *sk) | |
90 | { | |
91 | const struct dccp_sock *dp = dccp_sk(sk); | |
92 | const __u32 w_init = min(4 * dp->dccps_mss_cache, | |
93 | max(2 * dp->dccps_mss_cache, 4380U)); | |
94 | ||
95 | return scaled_div(w_init << 6, ccid3_hc_tx_sk(sk)->ccid3hctx_rtt); | |
96 | } | |
97 | ||
17893bc1 | 98 | /* |
1266adee | 99 | * Recalculate t_ipi and delta (should be called whenever X changes) |
17893bc1 | 100 | */ |
1266adee | 101 | static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx) |
7c657876 | 102 | { |
1a21e49a | 103 | /* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */ |
b2449fdc GR |
104 | hctx->ccid3hctx_t_ipi = scaled_div32(((u64)hctx->ccid3hctx_s) << 6, |
105 | hctx->ccid3hctx_x); | |
7c657876 | 106 | |
17893bc1 | 107 | /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ |
1f2333ae ACM |
108 | hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2, |
109 | TFRC_OPSYS_HALF_TIME_GRAN); | |
8699be7d | 110 | |
1761f7d7 | 111 | ccid3_pr_debug("t_ipi=%u, delta=%u, s=%u, X=%u\n", |
8699be7d | 112 | hctx->ccid3hctx_t_ipi, hctx->ccid3hctx_delta, |
1761f7d7 | 113 | hctx->ccid3hctx_s, (unsigned)(hctx->ccid3hctx_x >> 6)); |
8699be7d | 114 | |
7c657876 | 115 | } |
aa97efd9 GR |
116 | |
117 | /** | |
118 | * ccid3_hc_tx_update_x - Update allowed sending rate X | |
119 | * @stamp: most recent time if available - can be left NULL. | |
120 | * This function tracks draft rfc3448bis, check there for latest details. | |
5c3fbb6a | 121 | * |
1a21e49a GR |
122 | * Note: X and X_recv are both stored in units of 64 * bytes/second, to support |
123 | * fine-grained resolution of sending rates. This requires scaling by 2^6 | |
124 | * throughout the code. Only X_calc is unscaled (in bytes/second). | |
125 | * | |
1a21e49a | 126 | */ |
aa97efd9 | 127 | static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp) |
a79ef76f | 128 | |
7c657876 | 129 | { |
59725dc2 | 130 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
0c150efb | 131 | __u64 min_rate = 2 * hctx->ccid3hctx_x_recv; |
1a21e49a | 132 | const __u64 old_x = hctx->ccid3hctx_x; |
aa97efd9 | 133 | ktime_t now = stamp? *stamp : ktime_get_real(); |
7c657876 | 134 | |
0c150efb GR |
135 | /* |
136 | * Handle IDLE periods: do not reduce below RFC3390 initial sending rate | |
137 | * when idling [RFC 4342, 5.1]. See also draft-ietf-dccp-rfc3448bis. | |
138 | * For consistency with X and X_recv, min_rate is also scaled by 2^6. | |
139 | */ | |
140 | if (unlikely(hctx->ccid3hctx_idle)) { | |
141 | min_rate = rfc3390_initial_rate(sk); | |
142 | min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv); | |
143 | } | |
144 | ||
44158306 | 145 | if (hctx->ccid3hctx_p > 0) { |
1a21e49a | 146 | |
9e8efc82 | 147 | hctx->ccid3hctx_x = min(((__u64)hctx->ccid3hctx_x_calc) << 6, |
0c150efb | 148 | min_rate); |
9e8efc82 GR |
149 | hctx->ccid3hctx_x = max(hctx->ccid3hctx_x, |
150 | (((__u64)hctx->ccid3hctx_s) << 6) / | |
8109b02b | 151 | TFRC_T_MBI); |
a79ef76f | 152 | |
aa97efd9 GR |
153 | } else if (ktime_us_delta(now, hctx->ccid3hctx_t_ld) |
154 | - (s64)hctx->ccid3hctx_rtt >= 0) { | |
ac198ea8 | 155 | |
aa97efd9 GR |
156 | hctx->ccid3hctx_x = |
157 | max(min(2 * hctx->ccid3hctx_x, min_rate), | |
158 | scaled_div(((__u64)hctx->ccid3hctx_s) << 6, | |
159 | hctx->ccid3hctx_rtt)); | |
160 | hctx->ccid3hctx_t_ld = now; | |
ff586298 | 161 | } |
b6ee3d4a | 162 | |
8699be7d | 163 | if (hctx->ccid3hctx_x != old_x) { |
1761f7d7 GR |
164 | ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, " |
165 | "X_recv=%u\n", (unsigned)(old_x >> 6), | |
166 | (unsigned)(hctx->ccid3hctx_x >> 6), | |
167 | hctx->ccid3hctx_x_calc, | |
168 | (unsigned)(hctx->ccid3hctx_x_recv >> 6)); | |
8699be7d | 169 | |
1266adee | 170 | ccid3_update_send_interval(hctx); |
8699be7d | 171 | } |
7c657876 ACM |
172 | } |
173 | ||
78ad713d | 174 | /* |
8109b02b ACM |
175 | * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1) |
176 | * @len: DCCP packet payload size in bytes | |
78ad713d GR |
177 | */ |
178 | static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len) | |
179 | { | |
1266adee GR |
180 | const u16 old_s = hctx->ccid3hctx_s; |
181 | ||
182 | hctx->ccid3hctx_s = old_s == 0 ? len : (9 * old_s + len) / 10; | |
183 | ||
184 | if (hctx->ccid3hctx_s != old_s) | |
185 | ccid3_update_send_interval(hctx); | |
78ad713d GR |
186 | } |
187 | ||
9f8681db | 188 | /* |
8109b02b ACM |
189 | * Update Window Counter using the algorithm from [RFC 4342, 8.1]. |
190 | * The algorithm is not applicable if RTT < 4 microseconds. | |
9f8681db GR |
191 | */ |
192 | static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hctx, | |
8132da4d | 193 | ktime_t now) |
9f8681db | 194 | { |
9f8681db GR |
195 | u32 quarter_rtts; |
196 | ||
197 | if (unlikely(hctx->ccid3hctx_rtt < 4)) /* avoid divide-by-zero */ | |
198 | return; | |
199 | ||
8132da4d GR |
200 | quarter_rtts = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count); |
201 | quarter_rtts /= hctx->ccid3hctx_rtt / 4; | |
9f8681db GR |
202 | |
203 | if (quarter_rtts > 0) { | |
8132da4d | 204 | hctx->ccid3hctx_t_last_win_count = now; |
9f8681db GR |
205 | hctx->ccid3hctx_last_win_count += min_t(u32, quarter_rtts, 5); |
206 | hctx->ccid3hctx_last_win_count &= 0xF; /* mod 16 */ | |
9f8681db GR |
207 | } |
208 | } | |
209 | ||
7c657876 ACM |
210 | static void ccid3_hc_tx_no_feedback_timer(unsigned long data) |
211 | { | |
212 | struct sock *sk = (struct sock *)data; | |
59725dc2 | 213 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
2a1fda6f | 214 | unsigned long t_nfb = USEC_PER_SEC / 5; |
7c657876 ACM |
215 | |
216 | bh_lock_sock(sk); | |
217 | if (sock_owned_by_user(sk)) { | |
218 | /* Try again later. */ | |
219 | /* XXX: set some sensible MIB */ | |
48e03eee | 220 | goto restart_timer; |
7c657876 ACM |
221 | } |
222 | ||
a9672411 | 223 | ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk, |
7c657876 | 224 | ccid3_tx_state_name(hctx->ccid3hctx_state)); |
a9672411 | 225 | |
0c150efb GR |
226 | hctx->ccid3hctx_idle = 1; |
227 | ||
7c657876 | 228 | switch (hctx->ccid3hctx_state) { |
7c657876 | 229 | case TFRC_SSTATE_NO_FBACK: |
a79ef76f | 230 | /* RFC 3448, 4.4: Halve send rate directly */ |
9e8efc82 GR |
231 | hctx->ccid3hctx_x = max(hctx->ccid3hctx_x / 2, |
232 | (((__u64)hctx->ccid3hctx_s) << 6) / | |
233 | TFRC_T_MBI); | |
7c657876 | 234 | |
a9672411 GR |
235 | ccid3_pr_debug("%s(%p, state=%s), updated tx rate to %u " |
236 | "bytes/s\n", dccp_role(sk), sk, | |
1f2333ae | 237 | ccid3_tx_state_name(hctx->ccid3hctx_state), |
1a21e49a | 238 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
48e03eee GR |
239 | /* The value of R is still undefined and so we can not recompute |
240 | * the timout value. Keep initial value as per [RFC 4342, 5]. */ | |
2a1fda6f | 241 | t_nfb = TFRC_INITIAL_TIMEOUT; |
1266adee | 242 | ccid3_update_send_interval(hctx); |
7c657876 ACM |
243 | break; |
244 | case TFRC_SSTATE_FBACK: | |
1f2333ae | 245 | /* |
0c150efb GR |
246 | * Modify the cached value of X_recv [RFC 3448, 4.4] |
247 | * | |
248 | * If (p == 0 || X_calc > 2 * X_recv) | |
249 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); | |
250 | * Else | |
251 | * X_recv = X_calc / 4; | |
252 | * | |
253 | * Note that X_recv is scaled by 2^6 while X_calc is not | |
1f2333ae | 254 | */ |
0c150efb GR |
255 | BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc); |
256 | ||
257 | if (hctx->ccid3hctx_p == 0 || | |
258 | (hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))) { | |
259 | ||
260 | hctx->ccid3hctx_x_recv = | |
261 | max(hctx->ccid3hctx_x_recv / 2, | |
262 | (((__u64)hctx->ccid3hctx_s) << 6) / | |
263 | (2 * TFRC_T_MBI)); | |
0c150efb GR |
264 | } else { |
265 | hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc; | |
266 | hctx->ccid3hctx_x_recv <<= 4; | |
7c657876 | 267 | } |
0c150efb | 268 | /* Now recalculate X [RFC 3448, 4.3, step (4)] */ |
aa97efd9 | 269 | ccid3_hc_tx_update_x(sk, NULL); |
6b5e633a ACM |
270 | /* |
271 | * Schedule no feedback timer to expire in | |
8a508ac2 GR |
272 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
273 | * See comments in packet_recv() regarding the value of t_RTO. | |
6b5e633a | 274 | */ |
8a508ac2 | 275 | t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi); |
7c657876 | 276 | break; |
59348b19 | 277 | case TFRC_SSTATE_NO_SENT: |
a9672411 | 278 | DCCP_BUG("%s(%p) - Illegal state NO_SENT", dccp_role(sk), sk); |
59348b19 GR |
279 | /* fall through */ |
280 | case TFRC_SSTATE_TERM: | |
7c657876 ACM |
281 | goto out; |
282 | } | |
283 | ||
48e03eee GR |
284 | restart_timer: |
285 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | |
c9eaf173 | 286 | jiffies + usecs_to_jiffies(t_nfb)); |
7c657876 ACM |
287 | out: |
288 | bh_unlock_sock(sk); | |
289 | sock_put(sk); | |
290 | } | |
291 | ||
7da7f456 GR |
292 | /* |
293 | * returns | |
294 | * > 0: delay (in msecs) that should pass before actually sending | |
295 | * = 0: can send immediately | |
296 | * < 0: error condition; do not send packet | |
297 | */ | |
6b57c93d | 298 | static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
299 | { |
300 | struct dccp_sock *dp = dccp_sk(sk); | |
59725dc2 | 301 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
8132da4d GR |
302 | ktime_t now = ktime_get_real(); |
303 | s64 delay; | |
7c657876 | 304 | |
7c657876 | 305 | /* |
da335baf GR |
306 | * This function is called only for Data and DataAck packets. Sending |
307 | * zero-sized Data(Ack)s is theoretically possible, but for congestion | |
308 | * control this case is pathological - ignore it. | |
7c657876 | 309 | */ |
6b57c93d | 310 | if (unlikely(skb->len == 0)) |
da335baf | 311 | return -EBADMSG; |
7c657876 | 312 | |
7c657876 ACM |
313 | switch (hctx->ccid3hctx_state) { |
314 | case TFRC_SSTATE_NO_SENT: | |
1f2333ae | 315 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, |
8109b02b | 316 | (jiffies + |
c9eaf173 | 317 | usecs_to_jiffies(TFRC_INITIAL_TIMEOUT))); |
7c657876 ACM |
318 | hctx->ccid3hctx_last_win_count = 0; |
319 | hctx->ccid3hctx_t_last_win_count = now; | |
90feeb95 GR |
320 | |
321 | /* Set t_0 for initial packet */ | |
7c657876 | 322 | hctx->ccid3hctx_t_nom = now; |
30833ffe GR |
323 | |
324 | hctx->ccid3hctx_s = skb->len; | |
325 | ||
326 | /* | |
327 | * Use initial RTT sample when available: recommended by erratum | |
328 | * to RFC 4342. This implements the initialisation procedure of | |
329 | * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6. | |
330 | */ | |
331 | if (dp->dccps_syn_rtt) { | |
332 | ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt); | |
333 | hctx->ccid3hctx_rtt = dp->dccps_syn_rtt; | |
334 | hctx->ccid3hctx_x = rfc3390_initial_rate(sk); | |
23f062af | 335 | hctx->ccid3hctx_t_ld = now; |
30833ffe GR |
336 | } else { |
337 | /* Sender does not have RTT sample: X = MSS/second */ | |
338 | hctx->ccid3hctx_x = dp->dccps_mss_cache; | |
339 | hctx->ccid3hctx_x <<= 6; | |
340 | } | |
341 | ccid3_update_send_interval(hctx); | |
342 | ||
343 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); | |
7c657876 ACM |
344 | break; |
345 | case TFRC_SSTATE_NO_FBACK: | |
346 | case TFRC_SSTATE_FBACK: | |
8132da4d | 347 | delay = ktime_us_delta(hctx->ccid3hctx_t_nom, now); |
8699be7d | 348 | ccid3_pr_debug("delay=%ld\n", (long)delay); |
91cf5a17 | 349 | /* |
8109b02b | 350 | * Scheduling of packet transmissions [RFC 3448, 4.6] |
91cf5a17 GR |
351 | * |
352 | * if (t_now > t_nom - delta) | |
353 | * // send the packet now | |
354 | * else | |
355 | * // send the packet in (t_nom - t_now) milliseconds. | |
356 | */ | |
49d66a70 | 357 | if (delay - (s64)hctx->ccid3hctx_delta >= 1000) |
8132da4d | 358 | return (u32)delay / 1000L; |
9f8681db | 359 | |
8132da4d | 360 | ccid3_hc_tx_update_win_count(hctx, now); |
7c657876 | 361 | break; |
59348b19 | 362 | case TFRC_SSTATE_TERM: |
a9672411 | 363 | DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); |
7da7f456 | 364 | return -EINVAL; |
7c657876 ACM |
365 | } |
366 | ||
7da7f456 GR |
367 | /* prepare to send now (add options etc.) */ |
368 | dp->dccps_hc_tx_insert_options = 1; | |
e312d100 | 369 | DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; |
0c150efb | 370 | hctx->ccid3hctx_idle = 0; |
e312d100 GR |
371 | |
372 | /* set the nominal send time for the next following packet */ | |
8132da4d GR |
373 | hctx->ccid3hctx_t_nom = ktime_add_us(hctx->ccid3hctx_t_nom, |
374 | hctx->ccid3hctx_t_ipi); | |
7da7f456 | 375 | return 0; |
7c657876 ACM |
376 | } |
377 | ||
8109b02b ACM |
378 | static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, |
379 | unsigned int len) | |
7c657876 | 380 | { |
59725dc2 | 381 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
6b57c93d | 382 | struct dccp_tx_hist_entry *packet; |
7c657876 | 383 | |
6b57c93d | 384 | ccid3_hc_tx_update_s(hctx, len); |
7c657876 | 385 | |
c5a1ae9a | 386 | packet = dccp_tx_hist_entry_new(ccid3_tx_hist, GFP_ATOMIC); |
6b57c93d | 387 | if (unlikely(packet == NULL)) { |
c5a1ae9a | 388 | DCCP_CRIT("packet history - out of memory!"); |
6b57c93d GR |
389 | return; |
390 | } | |
c5a1ae9a GR |
391 | dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, packet); |
392 | ||
0740d49c | 393 | packet->dccphtx_tstamp = ktime_get_real(); |
c5a1ae9a GR |
394 | packet->dccphtx_seqno = dccp_sk(sk)->dccps_gss; |
395 | packet->dccphtx_rtt = hctx->ccid3hctx_rtt; | |
396 | packet->dccphtx_sent = 1; | |
7c657876 ACM |
397 | } |
398 | ||
399 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) | |
400 | { | |
59725dc2 | 401 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 | 402 | struct ccid3_options_received *opt_recv; |
8c60f3fa | 403 | struct dccp_tx_hist_entry *packet; |
0740d49c | 404 | ktime_t now; |
2a1fda6f | 405 | unsigned long t_nfb; |
7dfee1a9 | 406 | u32 pinv, r_sample; |
1f2333ae | 407 | |
7c657876 ACM |
408 | /* we are only interested in ACKs */ |
409 | if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || | |
410 | DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) | |
411 | return; | |
412 | ||
413 | opt_recv = &hctx->ccid3hctx_options_received; | |
414 | ||
7c657876 | 415 | switch (hctx->ccid3hctx_state) { |
7c657876 ACM |
416 | case TFRC_SSTATE_NO_FBACK: |
417 | case TFRC_SSTATE_FBACK: | |
5c3fbb6a | 418 | /* get packet from history to look up t_recvdata */ |
8c60f3fa | 419 | packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist, |
8109b02b | 420 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
59d203f9 | 421 | if (unlikely(packet == NULL)) { |
5c3fbb6a | 422 | DCCP_WARN("%s(%p), seqno %llu(%s) doesn't exist " |
59348b19 | 423 | "in history!\n", dccp_role(sk), sk, |
59d203f9 | 424 | (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq, |
8109b02b | 425 | dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type)); |
7c657876 ACM |
426 | return; |
427 | } | |
428 | ||
1a21e49a | 429 | /* Update receive rate in units of 64 * bytes/second */ |
9e8efc82 GR |
430 | hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate; |
431 | hctx->ccid3hctx_x_recv <<= 6; | |
5c3fbb6a GR |
432 | |
433 | /* Update loss event rate */ | |
434 | pinv = opt_recv->ccid3or_loss_event_rate; | |
45393a66 | 435 | if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */ |
5c3fbb6a | 436 | hctx->ccid3hctx_p = 0; |
45393a66 | 437 | else /* can not exceed 100% */ |
8109b02b | 438 | hctx->ccid3hctx_p = 1000000 / pinv; |
5c3fbb6a | 439 | |
9823b7b5 | 440 | now = ktime_get_real(); |
5c3fbb6a GR |
441 | /* |
442 | * Calculate new round trip sample as per [RFC 3448, 4.3] by | |
8109b02b | 443 | * R_sample = (now - t_recvdata) - t_elapsed |
5c3fbb6a | 444 | */ |
3393da82 | 445 | r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, packet->dccphtx_tstamp)); |
5c3fbb6a | 446 | |
7dfee1a9 GR |
447 | /* |
448 | * Update RTT estimate by | |
7c657876 ACM |
449 | * If (No feedback recv) |
450 | * R = R_sample; | |
451 | * Else | |
452 | * R = q * R + (1 - q) * R_sample; | |
453 | * | |
454 | * q is a constant, RFC 3448 recomments 0.9 | |
455 | */ | |
456 | if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) { | |
1a21e49a GR |
457 | /* |
458 | * Larger Initial Windows [RFC 4342, sec. 5] | |
1a21e49a | 459 | */ |
a79ef76f | 460 | hctx->ccid3hctx_rtt = r_sample; |
a21f9f96 | 461 | hctx->ccid3hctx_x = rfc3390_initial_rate(sk); |
9823b7b5 | 462 | hctx->ccid3hctx_t_ld = now; |
a79ef76f | 463 | |
1266adee | 464 | ccid3_update_send_interval(hctx); |
7c657876 | 465 | |
a21f9f96 | 466 | ccid3_pr_debug("%s(%p), s=%u, MSS=%u, " |
7dfee1a9 | 467 | "R_sample=%uus, X=%u\n", dccp_role(sk), |
0f08461e | 468 | sk, hctx->ccid3hctx_s, |
1b07a95a | 469 | dccp_sk(sk)->dccps_mss_cache, r_sample, |
1a21e49a | 470 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
7c657876 | 471 | |
5c3fbb6a GR |
472 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); |
473 | } else { | |
474 | hctx->ccid3hctx_rtt = (9 * hctx->ccid3hctx_rtt + | |
7dfee1a9 | 475 | r_sample) / 10; |
7c657876 | 476 | |
ff586298 GR |
477 | /* Update sending rate (step 4 of [RFC 3448, 4.3]) */ |
478 | if (hctx->ccid3hctx_p > 0) | |
479 | hctx->ccid3hctx_x_calc = | |
480 | tfrc_calc_x(hctx->ccid3hctx_s, | |
481 | hctx->ccid3hctx_rtt, | |
482 | hctx->ccid3hctx_p); | |
aa97efd9 | 483 | ccid3_hc_tx_update_x(sk, &now); |
7c657876 | 484 | |
7dfee1a9 | 485 | ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, " |
8109b02b ACM |
486 | "p=%u, X_calc=%u, X_recv=%u, X=%u\n", |
487 | dccp_role(sk), | |
7dfee1a9 | 488 | sk, hctx->ccid3hctx_rtt, r_sample, |
5c3fbb6a GR |
489 | hctx->ccid3hctx_s, hctx->ccid3hctx_p, |
490 | hctx->ccid3hctx_x_calc, | |
9e8efc82 | 491 | (unsigned)(hctx->ccid3hctx_x_recv >> 6), |
8109b02b | 492 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
7c657876 ACM |
493 | } |
494 | ||
495 | /* unschedule no feedback timer */ | |
496 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); | |
497 | ||
7c657876 | 498 | /* remove all packets older than the one acked from history */ |
8c60f3fa ACM |
499 | dccp_tx_hist_purge_older(ccid3_tx_hist, |
500 | &hctx->ccid3hctx_hist, packet); | |
c530cfb1 | 501 | /* |
8109b02b ACM |
502 | * As we have calculated new ipi, delta, t_nom it is possible |
503 | * that we now can send a packet, so wake up dccp_wait_for_ccid | |
c530cfb1 ACM |
504 | */ |
505 | sk->sk_write_space(sk); | |
8c60f3fa | 506 | |
8a508ac2 GR |
507 | /* |
508 | * Update timeout interval for the nofeedback timer. | |
509 | * We use a configuration option to increase the lower bound. | |
8109b02b ACM |
510 | * This can help avoid triggering the nofeedback timer too |
511 | * often ('spinning') on LANs with small RTTs. | |
8a508ac2 | 512 | */ |
5d0dbc4a | 513 | hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt, |
8a508ac2 | 514 | CONFIG_IP_DCCP_CCID3_RTO * |
8109b02b | 515 | (USEC_PER_SEC/1000)); |
1f2333ae ACM |
516 | /* |
517 | * Schedule no feedback timer to expire in | |
8a508ac2 | 518 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
1f2333ae | 519 | */ |
8a508ac2 | 520 | t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi); |
7c657876 | 521 | |
a9672411 | 522 | ccid3_pr_debug("%s(%p), Scheduled no feedback timer to " |
8109b02b ACM |
523 | "expire in %lu jiffies (%luus)\n", |
524 | dccp_role(sk), | |
a9672411 GR |
525 | sk, usecs_to_jiffies(t_nfb), t_nfb); |
526 | ||
527 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | |
2a1fda6f | 528 | jiffies + usecs_to_jiffies(t_nfb)); |
7c657876 ACM |
529 | |
530 | /* set idle flag */ | |
bf58a381 | 531 | hctx->ccid3hctx_idle = 1; |
7c657876 | 532 | break; |
151a9931 | 533 | case TFRC_SSTATE_NO_SENT: /* fall through */ |
5e19e3fc | 534 | case TFRC_SSTATE_TERM: /* ignore feedback when closing */ |
7c657876 ACM |
535 | break; |
536 | } | |
537 | } | |
538 | ||
7c657876 | 539 | static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, |
1f2333ae ACM |
540 | unsigned char len, u16 idx, |
541 | unsigned char *value) | |
7c657876 ACM |
542 | { |
543 | int rc = 0; | |
59725dc2 ACM |
544 | const struct dccp_sock *dp = dccp_sk(sk); |
545 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); | |
7c657876 ACM |
546 | struct ccid3_options_received *opt_recv; |
547 | ||
7c657876 ACM |
548 | opt_recv = &hctx->ccid3hctx_options_received; |
549 | ||
550 | if (opt_recv->ccid3or_seqno != dp->dccps_gsr) { | |
551 | opt_recv->ccid3or_seqno = dp->dccps_gsr; | |
552 | opt_recv->ccid3or_loss_event_rate = ~0; | |
553 | opt_recv->ccid3or_loss_intervals_idx = 0; | |
554 | opt_recv->ccid3or_loss_intervals_len = 0; | |
555 | opt_recv->ccid3or_receive_rate = 0; | |
556 | } | |
557 | ||
558 | switch (option) { | |
559 | case TFRC_OPT_LOSS_EVENT_RATE: | |
59d203f9 | 560 | if (unlikely(len != 4)) { |
a9672411 | 561 | DCCP_WARN("%s(%p), invalid len %d " |
59348b19 GR |
562 | "for TFRC_OPT_LOSS_EVENT_RATE\n", |
563 | dccp_role(sk), sk, len); | |
7c657876 ACM |
564 | rc = -EINVAL; |
565 | } else { | |
8109b02b ACM |
566 | opt_recv->ccid3or_loss_event_rate = |
567 | ntohl(*(__be32 *)value); | |
a9672411 | 568 | ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n", |
7c657876 ACM |
569 | dccp_role(sk), sk, |
570 | opt_recv->ccid3or_loss_event_rate); | |
571 | } | |
572 | break; | |
573 | case TFRC_OPT_LOSS_INTERVALS: | |
574 | opt_recv->ccid3or_loss_intervals_idx = idx; | |
575 | opt_recv->ccid3or_loss_intervals_len = len; | |
a9672411 | 576 | ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n", |
7c657876 ACM |
577 | dccp_role(sk), sk, |
578 | opt_recv->ccid3or_loss_intervals_idx, | |
579 | opt_recv->ccid3or_loss_intervals_len); | |
580 | break; | |
581 | case TFRC_OPT_RECEIVE_RATE: | |
59d203f9 | 582 | if (unlikely(len != 4)) { |
a9672411 | 583 | DCCP_WARN("%s(%p), invalid len %d " |
59348b19 GR |
584 | "for TFRC_OPT_RECEIVE_RATE\n", |
585 | dccp_role(sk), sk, len); | |
7c657876 ACM |
586 | rc = -EINVAL; |
587 | } else { | |
8109b02b ACM |
588 | opt_recv->ccid3or_receive_rate = |
589 | ntohl(*(__be32 *)value); | |
a9672411 | 590 | ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n", |
7c657876 ACM |
591 | dccp_role(sk), sk, |
592 | opt_recv->ccid3or_receive_rate); | |
593 | } | |
594 | break; | |
595 | } | |
596 | ||
597 | return rc; | |
598 | } | |
599 | ||
91f0ebf7 | 600 | static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk) |
7c657876 | 601 | { |
91f0ebf7 | 602 | struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid); |
7c657876 | 603 | |
78ad713d | 604 | hctx->ccid3hctx_s = 0; |
fe0499ae | 605 | hctx->ccid3hctx_rtt = 0; |
7c657876 ACM |
606 | hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT; |
607 | INIT_LIST_HEAD(&hctx->ccid3hctx_hist); | |
aa5d7df3 | 608 | |
8109b02b ACM |
609 | hctx->ccid3hctx_no_feedback_timer.function = |
610 | ccid3_hc_tx_no_feedback_timer; | |
aa5d7df3 | 611 | hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk; |
7c657876 ACM |
612 | init_timer(&hctx->ccid3hctx_no_feedback_timer); |
613 | ||
614 | return 0; | |
615 | } | |
616 | ||
617 | static void ccid3_hc_tx_exit(struct sock *sk) | |
618 | { | |
59725dc2 | 619 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 | 620 | |
7c657876 ACM |
621 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM); |
622 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); | |
623 | ||
624 | /* Empty packet history */ | |
8c60f3fa | 625 | dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist); |
7c657876 ACM |
626 | } |
627 | ||
9bf17475 GR |
628 | static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) |
629 | { | |
2e86908f | 630 | struct ccid3_hc_tx_sock *hctx; |
9bf17475 GR |
631 | |
632 | /* Listen socks doesn't have a private CCID block */ | |
633 | if (sk->sk_state == DCCP_LISTEN) | |
634 | return; | |
635 | ||
2e86908f | 636 | hctx = ccid3_hc_tx_sk(sk); |
9bf17475 GR |
637 | info->tcpi_rto = hctx->ccid3hctx_t_rto; |
638 | info->tcpi_rtt = hctx->ccid3hctx_rtt; | |
639 | } | |
640 | ||
641 | static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, | |
642 | u32 __user *optval, int __user *optlen) | |
643 | { | |
2e86908f | 644 | const struct ccid3_hc_tx_sock *hctx; |
9bf17475 GR |
645 | const void *val; |
646 | ||
647 | /* Listen socks doesn't have a private CCID block */ | |
648 | if (sk->sk_state == DCCP_LISTEN) | |
649 | return -EINVAL; | |
650 | ||
2e86908f | 651 | hctx = ccid3_hc_tx_sk(sk); |
9bf17475 GR |
652 | switch (optname) { |
653 | case DCCP_SOCKOPT_CCID_TX_INFO: | |
654 | if (len < sizeof(hctx->ccid3hctx_tfrc)) | |
655 | return -EINVAL; | |
656 | len = sizeof(hctx->ccid3hctx_tfrc); | |
657 | val = &hctx->ccid3hctx_tfrc; | |
658 | break; | |
659 | default: | |
660 | return -ENOPROTOOPT; | |
661 | } | |
662 | ||
663 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) | |
664 | return -EFAULT; | |
665 | ||
666 | return 0; | |
667 | } | |
668 | ||
7c657876 | 669 | /* |
9bf17475 | 670 | * Receiver Half-Connection Routines |
7c657876 | 671 | */ |
56724aa4 | 672 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
7c657876 ACM |
673 | static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) |
674 | { | |
675 | static char *ccid3_rx_state_names[] = { | |
676 | [TFRC_RSTATE_NO_DATA] = "NO_DATA", | |
677 | [TFRC_RSTATE_DATA] = "DATA", | |
678 | [TFRC_RSTATE_TERM] = "TERM", | |
679 | }; | |
680 | ||
681 | return ccid3_rx_state_names[state]; | |
682 | } | |
683 | #endif | |
684 | ||
c25a18ba ACM |
685 | static void ccid3_hc_rx_set_state(struct sock *sk, |
686 | enum ccid3_hc_rx_states state) | |
7c657876 | 687 | { |
59725dc2 | 688 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 ACM |
689 | enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state; |
690 | ||
691 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | |
1f2333ae ACM |
692 | dccp_role(sk), sk, ccid3_rx_state_name(oldstate), |
693 | ccid3_rx_state_name(state)); | |
7c657876 ACM |
694 | WARN_ON(state == oldstate); |
695 | hcrx->ccid3hcrx_state = state; | |
696 | } | |
697 | ||
78ad713d GR |
698 | static inline void ccid3_hc_rx_update_s(struct ccid3_hc_rx_sock *hcrx, int len) |
699 | { | |
700 | if (unlikely(len == 0)) /* don't update on empty packets (e.g. ACKs) */ | |
701 | ccid3_pr_debug("Packet payload length is 0 - not updating\n"); | |
702 | else | |
703 | hcrx->ccid3hcrx_s = hcrx->ccid3hcrx_s == 0 ? len : | |
704 | (9 * hcrx->ccid3hcrx_s + len) / 10; | |
705 | } | |
706 | ||
7c657876 ACM |
707 | static void ccid3_hc_rx_send_feedback(struct sock *sk) |
708 | { | |
59725dc2 | 709 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 | 710 | struct dccp_sock *dp = dccp_sk(sk); |
8c60f3fa | 711 | struct dccp_rx_hist_entry *packet; |
e7c23357 | 712 | ktime_t now; |
0f9e5b57 | 713 | suseconds_t delta; |
7c657876 | 714 | |
a9672411 | 715 | ccid3_pr_debug("%s(%p) - entry \n", dccp_role(sk), sk); |
7c657876 | 716 | |
e7a81c6d | 717 | now = ktime_get_real(); |
b6ee3d4a | 718 | |
7c657876 ACM |
719 | switch (hcrx->ccid3hcrx_state) { |
720 | case TFRC_RSTATE_NO_DATA: | |
721 | hcrx->ccid3hcrx_x_recv = 0; | |
722 | break; | |
0f9e5b57 | 723 | case TFRC_RSTATE_DATA: |
e7a81c6d ACM |
724 | delta = ktime_us_delta(now, |
725 | hcrx->ccid3hcrx_tstamp_last_feedback); | |
0f9e5b57 | 726 | DCCP_BUG_ON(delta < 0); |
b9039a2a GR |
727 | hcrx->ccid3hcrx_x_recv = |
728 | scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta); | |
7c657876 | 729 | break; |
59348b19 | 730 | case TFRC_RSTATE_TERM: |
a9672411 | 731 | DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); |
7c657876 ACM |
732 | return; |
733 | } | |
734 | ||
8c60f3fa | 735 | packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist); |
59d203f9 | 736 | if (unlikely(packet == NULL)) { |
a9672411 | 737 | DCCP_WARN("%s(%p), no data packet in history!\n", |
59348b19 | 738 | dccp_role(sk), sk); |
7c657876 ACM |
739 | return; |
740 | } | |
741 | ||
b6ee3d4a | 742 | hcrx->ccid3hcrx_tstamp_last_feedback = now; |
66a377c5 | 743 | hcrx->ccid3hcrx_ccval_last_counter = packet->dccphrx_ccval; |
7c657876 ACM |
744 | hcrx->ccid3hcrx_bytes_recv = 0; |
745 | ||
0f9e5b57 | 746 | /* Elapsed time information [RFC 4340, 13.2] in units of 10 * usecs */ |
e7c23357 | 747 | delta = ktime_us_delta(now, packet->dccphrx_tstamp); |
0f9e5b57 GR |
748 | DCCP_BUG_ON(delta < 0); |
749 | hcrx->ccid3hcrx_elapsed_time = delta / 10; | |
45393a66 | 750 | |
7c657876 | 751 | if (hcrx->ccid3hcrx_p == 0) |
45393a66 GR |
752 | hcrx->ccid3hcrx_pinv = ~0U; /* see RFC 4342, 8.5 */ |
753 | else if (hcrx->ccid3hcrx_p > 1000000) { | |
754 | DCCP_WARN("p (%u) > 100%%\n", hcrx->ccid3hcrx_p); | |
755 | hcrx->ccid3hcrx_pinv = 1; /* use 100% in this case */ | |
756 | } else | |
7c657876 | 757 | hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p; |
45393a66 | 758 | |
507d37cf | 759 | dp->dccps_hc_rx_insert_options = 1; |
7c657876 ACM |
760 | dccp_send_ack(sk); |
761 | } | |
762 | ||
2d0817d1 | 763 | static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) |
7c657876 | 764 | { |
2e86908f | 765 | const struct ccid3_hc_rx_sock *hcrx; |
60fe62e7 | 766 | __be32 x_recv, pinv; |
7c657876 | 767 | |
59d203f9 | 768 | if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) |
2d0817d1 | 769 | return 0; |
7c657876 | 770 | |
2e86908f | 771 | hcrx = ccid3_hc_rx_sk(sk); |
66a377c5 | 772 | DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_ccval_last_counter; |
4fded33b ACM |
773 | |
774 | if (dccp_packet_without_ack(skb)) | |
2d0817d1 ACM |
775 | return 0; |
776 | ||
4fded33b ACM |
777 | x_recv = htonl(hcrx->ccid3hcrx_x_recv); |
778 | pinv = htonl(hcrx->ccid3hcrx_pinv); | |
2d0817d1 ACM |
779 | |
780 | if ((hcrx->ccid3hcrx_elapsed_time != 0 && | |
781 | dccp_insert_option_elapsed_time(sk, skb, | |
782 | hcrx->ccid3hcrx_elapsed_time)) || | |
783 | dccp_insert_option_timestamp(sk, skb) || | |
784 | dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE, | |
8109b02b | 785 | &pinv, sizeof(pinv)) || |
2d0817d1 | 786 | dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE, |
8109b02b | 787 | &x_recv, sizeof(x_recv))) |
2d0817d1 ACM |
788 | return -1; |
789 | ||
790 | return 0; | |
7c657876 ACM |
791 | } |
792 | ||
66a377c5 | 793 | static int ccid3_hc_rx_detect_loss(struct sock *sk, |
c9eaf173 | 794 | struct dccp_rx_hist_entry *packet) |
7c657876 | 795 | { |
59725dc2 | 796 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
8109b02b ACM |
797 | struct dccp_rx_hist_entry *rx_hist = |
798 | dccp_rx_hist_head(&hcrx->ccid3hcrx_hist); | |
66a377c5 IM |
799 | u64 seqno = packet->dccphrx_seqno; |
800 | u64 tmp_seqno; | |
801 | int loss = 0; | |
802 | u8 ccval; | |
803 | ||
804 | ||
805 | tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss; | |
806 | ||
807 | if (!rx_hist || | |
808 | follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) { | |
809 | hcrx->ccid3hcrx_seqno_nonloss = seqno; | |
810 | hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval; | |
811 | goto detect_out; | |
812 | } | |
813 | ||
7c657876 | 814 | |
66a377c5 IM |
815 | while (dccp_delta_seqno(hcrx->ccid3hcrx_seqno_nonloss, seqno) |
816 | > TFRC_RECV_NUM_LATE_LOSS) { | |
817 | loss = 1; | |
cc4d6a3a | 818 | dccp_li_update_li(sk, |
cc0a910b ACM |
819 | &hcrx->ccid3hcrx_li_hist, |
820 | &hcrx->ccid3hcrx_hist, | |
e7c23357 | 821 | hcrx->ccid3hcrx_tstamp_last_feedback, |
cc0a910b ACM |
822 | hcrx->ccid3hcrx_s, |
823 | hcrx->ccid3hcrx_bytes_recv, | |
824 | hcrx->ccid3hcrx_x_recv, | |
825 | hcrx->ccid3hcrx_seqno_nonloss, | |
826 | hcrx->ccid3hcrx_ccval_nonloss); | |
66a377c5 IM |
827 | tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss; |
828 | dccp_inc_seqno(&tmp_seqno); | |
829 | hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno; | |
830 | dccp_inc_seqno(&tmp_seqno); | |
831 | while (dccp_rx_hist_find_entry(&hcrx->ccid3hcrx_hist, | |
832 | tmp_seqno, &ccval)) { | |
8109b02b | 833 | hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno; |
66a377c5 IM |
834 | hcrx->ccid3hcrx_ccval_nonloss = ccval; |
835 | dccp_inc_seqno(&tmp_seqno); | |
836 | } | |
837 | } | |
838 | ||
839 | /* FIXME - this code could be simplified with above while */ | |
840 | /* but works at moment */ | |
841 | if (follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) { | |
842 | hcrx->ccid3hcrx_seqno_nonloss = seqno; | |
843 | hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval; | |
844 | } | |
845 | ||
846 | detect_out: | |
847 | dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist, | |
848 | &hcrx->ccid3hcrx_li_hist, packet, | |
849 | hcrx->ccid3hcrx_seqno_nonloss); | |
850 | return loss; | |
7c657876 ACM |
851 | } |
852 | ||
7c657876 ACM |
853 | static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) |
854 | { | |
59725dc2 | 855 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
4fded33b | 856 | const struct dccp_options_received *opt_recv; |
8c60f3fa | 857 | struct dccp_rx_hist_entry *packet; |
7dfee1a9 | 858 | u32 p_prev, r_sample, rtt_prev; |
78ad713d | 859 | int loss, payload_size; |
9823b7b5 | 860 | ktime_t now; |
1f2333ae | 861 | |
59725dc2 | 862 | opt_recv = &dccp_sk(sk)->dccps_options_received; |
4fded33b | 863 | |
7c657876 ACM |
864 | switch (DCCP_SKB_CB(skb)->dccpd_type) { |
865 | case DCCP_PKT_ACK: | |
866 | if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) | |
867 | return; | |
9823b7b5 | 868 | case DCCP_PKT_DATAACK: |
4fded33b | 869 | if (opt_recv->dccpor_timestamp_echo == 0) |
7c657876 | 870 | break; |
3393da82 | 871 | r_sample = dccp_timestamp() - opt_recv->dccpor_timestamp_echo; |
66a377c5 | 872 | rtt_prev = hcrx->ccid3hcrx_rtt; |
3393da82 | 873 | r_sample = dccp_sample_rtt(sk, 10 * r_sample); |
b3a3077d ACM |
874 | |
875 | if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) | |
876 | hcrx->ccid3hcrx_rtt = r_sample; | |
877 | else | |
878 | hcrx->ccid3hcrx_rtt = (hcrx->ccid3hcrx_rtt * 9) / 10 + | |
879 | r_sample / 10; | |
880 | ||
66a377c5 | 881 | if (rtt_prev != hcrx->ccid3hcrx_rtt) |
a9672411 GR |
882 | ccid3_pr_debug("%s(%p), New RTT=%uus, elapsed time=%u\n", |
883 | dccp_role(sk), sk, hcrx->ccid3hcrx_rtt, | |
4fded33b | 884 | opt_recv->dccpor_elapsed_time); |
7c657876 ACM |
885 | break; |
886 | case DCCP_PKT_DATA: | |
887 | break; | |
59d203f9 | 888 | default: /* We're not interested in other packet types, move along */ |
7c657876 ACM |
889 | return; |
890 | } | |
891 | ||
e7c23357 | 892 | packet = dccp_rx_hist_entry_new(ccid3_rx_hist, opt_recv->dccpor_ndp, |
54e6ecb2 | 893 | skb, GFP_ATOMIC); |
59d203f9 | 894 | if (unlikely(packet == NULL)) { |
a9672411 | 895 | DCCP_WARN("%s(%p), Not enough mem to add rx packet " |
59348b19 | 896 | "to history, consider it lost!\n", dccp_role(sk), sk); |
7c657876 ACM |
897 | return; |
898 | } | |
899 | ||
66a377c5 | 900 | loss = ccid3_hc_rx_detect_loss(sk, packet); |
7c657876 ACM |
901 | |
902 | if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK) | |
903 | return; | |
904 | ||
78ad713d GR |
905 | payload_size = skb->len - dccp_hdr(skb)->dccph_doff * 4; |
906 | ccid3_hc_rx_update_s(hcrx, payload_size); | |
907 | ||
7c657876 ACM |
908 | switch (hcrx->ccid3hcrx_state) { |
909 | case TFRC_RSTATE_NO_DATA: | |
a9672411 GR |
910 | ccid3_pr_debug("%s(%p, state=%s), skb=%p, sending initial " |
911 | "feedback\n", dccp_role(sk), sk, | |
1f2333ae | 912 | dccp_state_name(sk->sk_state), skb); |
7c657876 ACM |
913 | ccid3_hc_rx_send_feedback(sk); |
914 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); | |
915 | return; | |
9823b7b5 | 916 | case TFRC_RSTATE_DATA: |
78ad713d | 917 | hcrx->ccid3hcrx_bytes_recv += payload_size; |
66a377c5 | 918 | if (loss) |
b6ee3d4a ACM |
919 | break; |
920 | ||
1faf0a1f ACM |
921 | now = ktime_get_real(); |
922 | if ((ktime_us_delta(now, hcrx->ccid3hcrx_tstamp_last_ack) - | |
923 | (s64)hcrx->ccid3hcrx_rtt) >= 0) { | |
b6ee3d4a ACM |
924 | hcrx->ccid3hcrx_tstamp_last_ack = now; |
925 | ccid3_hc_rx_send_feedback(sk); | |
7c657876 | 926 | } |
b6ee3d4a | 927 | return; |
59348b19 | 928 | case TFRC_RSTATE_TERM: |
a9672411 | 929 | DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); |
7c657876 ACM |
930 | return; |
931 | } | |
932 | ||
933 | /* Dealing with packet loss */ | |
a9672411 | 934 | ccid3_pr_debug("%s(%p, state=%s), data loss! Reacting...\n", |
4fded33b | 935 | dccp_role(sk), sk, dccp_state_name(sk->sk_state)); |
7c657876 | 936 | |
7c657876 | 937 | p_prev = hcrx->ccid3hcrx_p; |
c9eaf173 | 938 | |
7c657876 | 939 | /* Calculate loss event rate */ |
c0996660 IM |
940 | if (!list_empty(&hcrx->ccid3hcrx_li_hist)) { |
941 | u32 i_mean = dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist); | |
942 | ||
7c657876 | 943 | /* Scaling up by 1000000 as fixed decimal */ |
c0996660 IM |
944 | if (i_mean != 0) |
945 | hcrx->ccid3hcrx_p = 1000000 / i_mean; | |
59348b19 GR |
946 | } else |
947 | DCCP_BUG("empty loss history"); | |
7c657876 ACM |
948 | |
949 | if (hcrx->ccid3hcrx_p > p_prev) { | |
950 | ccid3_hc_rx_send_feedback(sk); | |
951 | return; | |
952 | } | |
953 | } | |
954 | ||
91f0ebf7 | 955 | static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk) |
7c657876 | 956 | { |
91f0ebf7 | 957 | struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid); |
7c657876 | 958 | |
a9672411 | 959 | ccid3_pr_debug("entry\n"); |
7c657876 | 960 | |
7c657876 ACM |
961 | hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA; |
962 | INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist); | |
ae6706f0 | 963 | INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist); |
1faf0a1f | 964 | hcrx->ccid3hcrx_tstamp_last_feedback = |
e7a81c6d | 965 | hcrx->ccid3hcrx_tstamp_last_ack = ktime_get_real(); |
78ad713d | 966 | hcrx->ccid3hcrx_s = 0; |
fe0499ae | 967 | hcrx->ccid3hcrx_rtt = 0; |
7c657876 ACM |
968 | return 0; |
969 | } | |
970 | ||
971 | static void ccid3_hc_rx_exit(struct sock *sk) | |
972 | { | |
59725dc2 | 973 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 | 974 | |
7c657876 ACM |
975 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM); |
976 | ||
977 | /* Empty packet history */ | |
8c60f3fa | 978 | dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist); |
7c657876 ACM |
979 | |
980 | /* Empty loss interval history */ | |
cc4d6a3a | 981 | dccp_li_hist_purge(&hcrx->ccid3hcrx_li_hist); |
7c657876 ACM |
982 | } |
983 | ||
2babe1f6 ACM |
984 | static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) |
985 | { | |
2e86908f | 986 | const struct ccid3_hc_rx_sock *hcrx; |
2babe1f6 | 987 | |
59c2353d ACM |
988 | /* Listen socks doesn't have a private CCID block */ |
989 | if (sk->sk_state == DCCP_LISTEN) | |
990 | return; | |
991 | ||
2e86908f | 992 | hcrx = ccid3_hc_rx_sk(sk); |
8109b02b ACM |
993 | info->tcpi_ca_state = hcrx->ccid3hcrx_state; |
994 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; | |
995 | info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt; | |
2babe1f6 ACM |
996 | } |
997 | ||
88f964db ACM |
998 | static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, |
999 | u32 __user *optval, int __user *optlen) | |
1000 | { | |
2e86908f | 1001 | const struct ccid3_hc_rx_sock *hcrx; |
88f964db | 1002 | const void *val; |
c9eaf173 | 1003 | |
88f964db ACM |
1004 | /* Listen socks doesn't have a private CCID block */ |
1005 | if (sk->sk_state == DCCP_LISTEN) | |
1006 | return -EINVAL; | |
1007 | ||
2e86908f | 1008 | hcrx = ccid3_hc_rx_sk(sk); |
88f964db ACM |
1009 | switch (optname) { |
1010 | case DCCP_SOCKOPT_CCID_RX_INFO: | |
1011 | if (len < sizeof(hcrx->ccid3hcrx_tfrc)) | |
1012 | return -EINVAL; | |
1013 | len = sizeof(hcrx->ccid3hcrx_tfrc); | |
1014 | val = &hcrx->ccid3hcrx_tfrc; | |
1015 | break; | |
1016 | default: | |
1017 | return -ENOPROTOOPT; | |
1018 | } | |
1019 | ||
1020 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) | |
1021 | return -EFAULT; | |
1022 | ||
1023 | return 0; | |
1024 | } | |
1025 | ||
91f0ebf7 | 1026 | static struct ccid_operations ccid3 = { |
3dd9a7c3 | 1027 | .ccid_id = DCCPC_CCID3, |
7c657876 ACM |
1028 | .ccid_name = "ccid3", |
1029 | .ccid_owner = THIS_MODULE, | |
91f0ebf7 | 1030 | .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock), |
7c657876 ACM |
1031 | .ccid_hc_tx_init = ccid3_hc_tx_init, |
1032 | .ccid_hc_tx_exit = ccid3_hc_tx_exit, | |
1033 | .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, | |
1034 | .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, | |
1035 | .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, | |
7c657876 | 1036 | .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, |
91f0ebf7 | 1037 | .ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock), |
7c657876 ACM |
1038 | .ccid_hc_rx_init = ccid3_hc_rx_init, |
1039 | .ccid_hc_rx_exit = ccid3_hc_rx_exit, | |
1040 | .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, | |
1041 | .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, | |
2babe1f6 ACM |
1042 | .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, |
1043 | .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, | |
88f964db ACM |
1044 | .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt, |
1045 | .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt, | |
7c657876 | 1046 | }; |
8109b02b | 1047 | |
56724aa4 | 1048 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
042d18f9 | 1049 | module_param(ccid3_debug, bool, 0444); |
7c657876 | 1050 | MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); |
56724aa4 | 1051 | #endif |
7c657876 ACM |
1052 | |
1053 | static __init int ccid3_module_init(void) | |
1054 | { | |
8c60f3fa | 1055 | int rc = -ENOBUFS; |
7c657876 | 1056 | |
8c60f3fa ACM |
1057 | ccid3_rx_hist = dccp_rx_hist_new("ccid3"); |
1058 | if (ccid3_rx_hist == NULL) | |
7c657876 ACM |
1059 | goto out; |
1060 | ||
8c60f3fa ACM |
1061 | ccid3_tx_hist = dccp_tx_hist_new("ccid3"); |
1062 | if (ccid3_tx_hist == NULL) | |
1063 | goto out_free_rx; | |
7c657876 | 1064 | |
7c657876 | 1065 | rc = ccid_register(&ccid3); |
8109b02b | 1066 | if (rc != 0) |
cc4d6a3a | 1067 | goto out_free_tx; |
7c657876 ACM |
1068 | out: |
1069 | return rc; | |
8c60f3fa | 1070 | |
8c60f3fa ACM |
1071 | out_free_tx: |
1072 | dccp_tx_hist_delete(ccid3_tx_hist); | |
1073 | ccid3_tx_hist = NULL; | |
1074 | out_free_rx: | |
1075 | dccp_rx_hist_delete(ccid3_rx_hist); | |
1076 | ccid3_rx_hist = NULL; | |
7c657876 ACM |
1077 | goto out; |
1078 | } | |
1079 | module_init(ccid3_module_init); | |
1080 | ||
1081 | static __exit void ccid3_module_exit(void) | |
1082 | { | |
1083 | ccid_unregister(&ccid3); | |
1084 | ||
8c60f3fa ACM |
1085 | if (ccid3_tx_hist != NULL) { |
1086 | dccp_tx_hist_delete(ccid3_tx_hist); | |
1087 | ccid3_tx_hist = NULL; | |
7c657876 | 1088 | } |
8c60f3fa ACM |
1089 | if (ccid3_rx_hist != NULL) { |
1090 | dccp_rx_hist_delete(ccid3_rx_hist); | |
1091 | ccid3_rx_hist = NULL; | |
7c657876 | 1092 | } |
7c657876 ACM |
1093 | } |
1094 | module_exit(ccid3_module_exit); | |
1095 | ||
e6bccd35 | 1096 | MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, " |
1f2333ae | 1097 | "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); |
7c657876 ACM |
1098 | MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); |
1099 | MODULE_LICENSE("GPL"); | |
1100 | MODULE_ALIAS("net-dccp-ccid-3"); |