Commit | Line | Data |
---|---|---|
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 | ||
76fd1e87 GR |
43 | #include <asm/unaligned.h> |
44 | ||
56724aa4 GR |
45 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
46 | static int ccid3_debug; | |
47 | #define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a) | |
7c657876 ACM |
48 | #else |
49 | #define ccid3_pr_debug(format, a...) | |
50 | #endif | |
51 | ||
a1d3a355 ACM |
52 | static struct dccp_tx_hist *ccid3_tx_hist; |
53 | static struct dccp_rx_hist *ccid3_rx_hist; | |
7c657876 | 54 | |
9bf17475 GR |
55 | /* |
56 | * Transmitter Half-Connection Routines | |
57 | */ | |
56724aa4 | 58 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
7c657876 ACM |
59 | static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) |
60 | { | |
61 | static char *ccid3_state_names[] = { | |
62 | [TFRC_SSTATE_NO_SENT] = "NO_SENT", | |
63 | [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", | |
64 | [TFRC_SSTATE_FBACK] = "FBACK", | |
65 | [TFRC_SSTATE_TERM] = "TERM", | |
66 | }; | |
67 | ||
68 | return ccid3_state_names[state]; | |
69 | } | |
70 | #endif | |
71 | ||
c25a18ba ACM |
72 | static void ccid3_hc_tx_set_state(struct sock *sk, |
73 | enum ccid3_hc_tx_states state) | |
7c657876 | 74 | { |
59725dc2 | 75 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 ACM |
76 | enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state; |
77 | ||
78 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | |
1f2333ae ACM |
79 | dccp_role(sk), sk, ccid3_tx_state_name(oldstate), |
80 | ccid3_tx_state_name(state)); | |
7c657876 ACM |
81 | WARN_ON(state == oldstate); |
82 | hctx->ccid3hctx_state = state; | |
83 | } | |
84 | ||
a21f9f96 GR |
85 | /* |
86 | * Compute the initial sending rate X_init according to RFC 3390: | |
87 | * w_init = min(4 * MSS, max(2 * MSS, 4380 bytes)) | |
88 | * X_init = w_init / RTT | |
89 | * For consistency with other parts of the code, X_init is scaled by 2^6. | |
90 | */ | |
91 | static inline u64 rfc3390_initial_rate(struct sock *sk) | |
92 | { | |
93 | const struct dccp_sock *dp = dccp_sk(sk); | |
94 | const __u32 w_init = min(4 * dp->dccps_mss_cache, | |
95 | max(2 * dp->dccps_mss_cache, 4380U)); | |
96 | ||
97 | return scaled_div(w_init << 6, ccid3_hc_tx_sk(sk)->ccid3hctx_rtt); | |
98 | } | |
99 | ||
17893bc1 | 100 | /* |
1266adee | 101 | * Recalculate t_ipi and delta (should be called whenever X changes) |
17893bc1 | 102 | */ |
1266adee | 103 | static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx) |
7c657876 | 104 | { |
1a21e49a | 105 | /* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */ |
b2449fdc GR |
106 | hctx->ccid3hctx_t_ipi = scaled_div32(((u64)hctx->ccid3hctx_s) << 6, |
107 | hctx->ccid3hctx_x); | |
7c657876 | 108 | |
17893bc1 | 109 | /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ |
1f2333ae ACM |
110 | hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2, |
111 | TFRC_OPSYS_HALF_TIME_GRAN); | |
8699be7d | 112 | |
1761f7d7 | 113 | ccid3_pr_debug("t_ipi=%u, delta=%u, s=%u, X=%u\n", |
8699be7d | 114 | hctx->ccid3hctx_t_ipi, hctx->ccid3hctx_delta, |
1761f7d7 | 115 | hctx->ccid3hctx_s, (unsigned)(hctx->ccid3hctx_x >> 6)); |
8699be7d | 116 | |
7c657876 | 117 | } |
aa97efd9 GR |
118 | |
119 | /** | |
120 | * ccid3_hc_tx_update_x - Update allowed sending rate X | |
121 | * @stamp: most recent time if available - can be left NULL. | |
122 | * This function tracks draft rfc3448bis, check there for latest details. | |
5c3fbb6a | 123 | * |
1a21e49a GR |
124 | * Note: X and X_recv are both stored in units of 64 * bytes/second, to support |
125 | * fine-grained resolution of sending rates. This requires scaling by 2^6 | |
126 | * throughout the code. Only X_calc is unscaled (in bytes/second). | |
127 | * | |
1a21e49a | 128 | */ |
aa97efd9 | 129 | static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp) |
a79ef76f | 130 | |
7c657876 | 131 | { |
59725dc2 | 132 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
0c150efb | 133 | __u64 min_rate = 2 * hctx->ccid3hctx_x_recv; |
1a21e49a | 134 | const __u64 old_x = hctx->ccid3hctx_x; |
aa97efd9 | 135 | ktime_t now = stamp? *stamp : ktime_get_real(); |
7c657876 | 136 | |
0c150efb GR |
137 | /* |
138 | * Handle IDLE periods: do not reduce below RFC3390 initial sending rate | |
139 | * when idling [RFC 4342, 5.1]. See also draft-ietf-dccp-rfc3448bis. | |
140 | * For consistency with X and X_recv, min_rate is also scaled by 2^6. | |
141 | */ | |
142 | if (unlikely(hctx->ccid3hctx_idle)) { | |
143 | min_rate = rfc3390_initial_rate(sk); | |
144 | min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv); | |
145 | } | |
146 | ||
44158306 | 147 | if (hctx->ccid3hctx_p > 0) { |
1a21e49a | 148 | |
9e8efc82 | 149 | hctx->ccid3hctx_x = min(((__u64)hctx->ccid3hctx_x_calc) << 6, |
0c150efb | 150 | min_rate); |
9e8efc82 GR |
151 | hctx->ccid3hctx_x = max(hctx->ccid3hctx_x, |
152 | (((__u64)hctx->ccid3hctx_s) << 6) / | |
8109b02b | 153 | TFRC_T_MBI); |
a79ef76f | 154 | |
aa97efd9 GR |
155 | } else if (ktime_us_delta(now, hctx->ccid3hctx_t_ld) |
156 | - (s64)hctx->ccid3hctx_rtt >= 0) { | |
ac198ea8 | 157 | |
aa97efd9 GR |
158 | hctx->ccid3hctx_x = |
159 | max(min(2 * hctx->ccid3hctx_x, min_rate), | |
160 | scaled_div(((__u64)hctx->ccid3hctx_s) << 6, | |
161 | hctx->ccid3hctx_rtt)); | |
162 | hctx->ccid3hctx_t_ld = now; | |
ff586298 | 163 | } |
b6ee3d4a | 164 | |
8699be7d | 165 | if (hctx->ccid3hctx_x != old_x) { |
1761f7d7 GR |
166 | ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, " |
167 | "X_recv=%u\n", (unsigned)(old_x >> 6), | |
168 | (unsigned)(hctx->ccid3hctx_x >> 6), | |
169 | hctx->ccid3hctx_x_calc, | |
170 | (unsigned)(hctx->ccid3hctx_x_recv >> 6)); | |
8699be7d | 171 | |
1266adee | 172 | ccid3_update_send_interval(hctx); |
8699be7d | 173 | } |
7c657876 ACM |
174 | } |
175 | ||
78ad713d | 176 | /* |
8109b02b ACM |
177 | * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1) |
178 | * @len: DCCP packet payload size in bytes | |
78ad713d GR |
179 | */ |
180 | static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len) | |
181 | { | |
1266adee GR |
182 | const u16 old_s = hctx->ccid3hctx_s; |
183 | ||
184 | hctx->ccid3hctx_s = old_s == 0 ? len : (9 * old_s + len) / 10; | |
185 | ||
186 | if (hctx->ccid3hctx_s != old_s) | |
187 | ccid3_update_send_interval(hctx); | |
78ad713d GR |
188 | } |
189 | ||
9f8681db | 190 | /* |
8109b02b ACM |
191 | * Update Window Counter using the algorithm from [RFC 4342, 8.1]. |
192 | * The algorithm is not applicable if RTT < 4 microseconds. | |
9f8681db GR |
193 | */ |
194 | static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hctx, | |
8132da4d | 195 | ktime_t now) |
9f8681db | 196 | { |
9f8681db GR |
197 | u32 quarter_rtts; |
198 | ||
199 | if (unlikely(hctx->ccid3hctx_rtt < 4)) /* avoid divide-by-zero */ | |
200 | return; | |
201 | ||
8132da4d GR |
202 | quarter_rtts = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count); |
203 | quarter_rtts /= hctx->ccid3hctx_rtt / 4; | |
9f8681db GR |
204 | |
205 | if (quarter_rtts > 0) { | |
8132da4d | 206 | hctx->ccid3hctx_t_last_win_count = now; |
9f8681db GR |
207 | hctx->ccid3hctx_last_win_count += min_t(u32, quarter_rtts, 5); |
208 | hctx->ccid3hctx_last_win_count &= 0xF; /* mod 16 */ | |
9f8681db GR |
209 | } |
210 | } | |
211 | ||
7c657876 ACM |
212 | static void ccid3_hc_tx_no_feedback_timer(unsigned long data) |
213 | { | |
214 | struct sock *sk = (struct sock *)data; | |
59725dc2 | 215 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
2a1fda6f | 216 | unsigned long t_nfb = USEC_PER_SEC / 5; |
7c657876 ACM |
217 | |
218 | bh_lock_sock(sk); | |
219 | if (sock_owned_by_user(sk)) { | |
220 | /* Try again later. */ | |
221 | /* XXX: set some sensible MIB */ | |
48e03eee | 222 | goto restart_timer; |
7c657876 ACM |
223 | } |
224 | ||
a9672411 | 225 | ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk, |
7c657876 | 226 | ccid3_tx_state_name(hctx->ccid3hctx_state)); |
a9672411 | 227 | |
0c150efb GR |
228 | hctx->ccid3hctx_idle = 1; |
229 | ||
7c657876 | 230 | switch (hctx->ccid3hctx_state) { |
7c657876 | 231 | case TFRC_SSTATE_NO_FBACK: |
a79ef76f | 232 | /* RFC 3448, 4.4: Halve send rate directly */ |
9e8efc82 GR |
233 | hctx->ccid3hctx_x = max(hctx->ccid3hctx_x / 2, |
234 | (((__u64)hctx->ccid3hctx_s) << 6) / | |
235 | TFRC_T_MBI); | |
7c657876 | 236 | |
a9672411 GR |
237 | ccid3_pr_debug("%s(%p, state=%s), updated tx rate to %u " |
238 | "bytes/s\n", dccp_role(sk), sk, | |
1f2333ae | 239 | ccid3_tx_state_name(hctx->ccid3hctx_state), |
1a21e49a | 240 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
48e03eee | 241 | /* The value of R is still undefined and so we can not recompute |
5e8e034c | 242 | * the timeout value. Keep initial value as per [RFC 4342, 5]. */ |
2a1fda6f | 243 | t_nfb = TFRC_INITIAL_TIMEOUT; |
1266adee | 244 | ccid3_update_send_interval(hctx); |
7c657876 ACM |
245 | break; |
246 | case TFRC_SSTATE_FBACK: | |
1f2333ae | 247 | /* |
0c150efb GR |
248 | * Modify the cached value of X_recv [RFC 3448, 4.4] |
249 | * | |
250 | * If (p == 0 || X_calc > 2 * X_recv) | |
251 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); | |
252 | * Else | |
253 | * X_recv = X_calc / 4; | |
254 | * | |
255 | * Note that X_recv is scaled by 2^6 while X_calc is not | |
1f2333ae | 256 | */ |
0c150efb GR |
257 | BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc); |
258 | ||
259 | if (hctx->ccid3hctx_p == 0 || | |
260 | (hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))) { | |
261 | ||
262 | hctx->ccid3hctx_x_recv = | |
263 | max(hctx->ccid3hctx_x_recv / 2, | |
264 | (((__u64)hctx->ccid3hctx_s) << 6) / | |
265 | (2 * TFRC_T_MBI)); | |
0c150efb GR |
266 | } else { |
267 | hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc; | |
268 | hctx->ccid3hctx_x_recv <<= 4; | |
7c657876 | 269 | } |
0c150efb | 270 | /* Now recalculate X [RFC 3448, 4.3, step (4)] */ |
aa97efd9 | 271 | ccid3_hc_tx_update_x(sk, NULL); |
6b5e633a ACM |
272 | /* |
273 | * Schedule no feedback timer to expire in | |
8a508ac2 GR |
274 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
275 | * See comments in packet_recv() regarding the value of t_RTO. | |
6b5e633a | 276 | */ |
8a508ac2 | 277 | t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi); |
7c657876 | 278 | break; |
59348b19 | 279 | case TFRC_SSTATE_NO_SENT: |
a9672411 | 280 | DCCP_BUG("%s(%p) - Illegal state NO_SENT", dccp_role(sk), sk); |
59348b19 GR |
281 | /* fall through */ |
282 | case TFRC_SSTATE_TERM: | |
7c657876 ACM |
283 | goto out; |
284 | } | |
285 | ||
48e03eee GR |
286 | restart_timer: |
287 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | |
c9eaf173 | 288 | jiffies + usecs_to_jiffies(t_nfb)); |
7c657876 ACM |
289 | out: |
290 | bh_unlock_sock(sk); | |
291 | sock_put(sk); | |
292 | } | |
293 | ||
7da7f456 GR |
294 | /* |
295 | * returns | |
296 | * > 0: delay (in msecs) that should pass before actually sending | |
297 | * = 0: can send immediately | |
298 | * < 0: error condition; do not send packet | |
299 | */ | |
6b57c93d | 300 | static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
301 | { |
302 | struct dccp_sock *dp = dccp_sk(sk); | |
59725dc2 | 303 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
8132da4d GR |
304 | ktime_t now = ktime_get_real(); |
305 | s64 delay; | |
7c657876 | 306 | |
7c657876 | 307 | /* |
da335baf GR |
308 | * This function is called only for Data and DataAck packets. Sending |
309 | * zero-sized Data(Ack)s is theoretically possible, but for congestion | |
310 | * control this case is pathological - ignore it. | |
7c657876 | 311 | */ |
6b57c93d | 312 | if (unlikely(skb->len == 0)) |
da335baf | 313 | return -EBADMSG; |
7c657876 | 314 | |
7c657876 ACM |
315 | switch (hctx->ccid3hctx_state) { |
316 | case TFRC_SSTATE_NO_SENT: | |
1f2333ae | 317 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, |
8109b02b | 318 | (jiffies + |
c9eaf173 | 319 | usecs_to_jiffies(TFRC_INITIAL_TIMEOUT))); |
7c657876 ACM |
320 | hctx->ccid3hctx_last_win_count = 0; |
321 | hctx->ccid3hctx_t_last_win_count = now; | |
90feeb95 GR |
322 | |
323 | /* Set t_0 for initial packet */ | |
7c657876 | 324 | hctx->ccid3hctx_t_nom = now; |
30833ffe GR |
325 | |
326 | hctx->ccid3hctx_s = skb->len; | |
327 | ||
328 | /* | |
329 | * Use initial RTT sample when available: recommended by erratum | |
330 | * to RFC 4342. This implements the initialisation procedure of | |
331 | * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6. | |
332 | */ | |
333 | if (dp->dccps_syn_rtt) { | |
334 | ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt); | |
335 | hctx->ccid3hctx_rtt = dp->dccps_syn_rtt; | |
336 | hctx->ccid3hctx_x = rfc3390_initial_rate(sk); | |
23f062af | 337 | hctx->ccid3hctx_t_ld = now; |
30833ffe GR |
338 | } else { |
339 | /* Sender does not have RTT sample: X = MSS/second */ | |
340 | hctx->ccid3hctx_x = dp->dccps_mss_cache; | |
341 | hctx->ccid3hctx_x <<= 6; | |
342 | } | |
343 | ccid3_update_send_interval(hctx); | |
344 | ||
345 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); | |
7c657876 ACM |
346 | break; |
347 | case TFRC_SSTATE_NO_FBACK: | |
348 | case TFRC_SSTATE_FBACK: | |
8132da4d | 349 | delay = ktime_us_delta(hctx->ccid3hctx_t_nom, now); |
8699be7d | 350 | ccid3_pr_debug("delay=%ld\n", (long)delay); |
91cf5a17 | 351 | /* |
8109b02b | 352 | * Scheduling of packet transmissions [RFC 3448, 4.6] |
91cf5a17 GR |
353 | * |
354 | * if (t_now > t_nom - delta) | |
355 | * // send the packet now | |
356 | * else | |
357 | * // send the packet in (t_nom - t_now) milliseconds. | |
358 | */ | |
49d66a70 | 359 | if (delay - (s64)hctx->ccid3hctx_delta >= 1000) |
8132da4d | 360 | return (u32)delay / 1000L; |
9f8681db | 361 | |
8132da4d | 362 | ccid3_hc_tx_update_win_count(hctx, now); |
7c657876 | 363 | break; |
59348b19 | 364 | case TFRC_SSTATE_TERM: |
a9672411 | 365 | DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); |
7da7f456 | 366 | return -EINVAL; |
7c657876 ACM |
367 | } |
368 | ||
7da7f456 GR |
369 | /* prepare to send now (add options etc.) */ |
370 | dp->dccps_hc_tx_insert_options = 1; | |
e312d100 | 371 | DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; |
0c150efb | 372 | hctx->ccid3hctx_idle = 0; |
e312d100 GR |
373 | |
374 | /* set the nominal send time for the next following packet */ | |
8132da4d GR |
375 | hctx->ccid3hctx_t_nom = ktime_add_us(hctx->ccid3hctx_t_nom, |
376 | hctx->ccid3hctx_t_ipi); | |
7da7f456 | 377 | return 0; |
7c657876 ACM |
378 | } |
379 | ||
8109b02b ACM |
380 | static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, |
381 | unsigned int len) | |
7c657876 | 382 | { |
59725dc2 | 383 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
6b57c93d | 384 | struct dccp_tx_hist_entry *packet; |
7c657876 | 385 | |
6b57c93d | 386 | ccid3_hc_tx_update_s(hctx, len); |
7c657876 | 387 | |
c5a1ae9a | 388 | packet = dccp_tx_hist_entry_new(ccid3_tx_hist, GFP_ATOMIC); |
6b57c93d | 389 | if (unlikely(packet == NULL)) { |
c5a1ae9a | 390 | DCCP_CRIT("packet history - out of memory!"); |
6b57c93d GR |
391 | return; |
392 | } | |
c5a1ae9a GR |
393 | dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, packet); |
394 | ||
0740d49c | 395 | packet->dccphtx_tstamp = ktime_get_real(); |
c5a1ae9a GR |
396 | packet->dccphtx_seqno = dccp_sk(sk)->dccps_gss; |
397 | packet->dccphtx_rtt = hctx->ccid3hctx_rtt; | |
398 | packet->dccphtx_sent = 1; | |
7c657876 ACM |
399 | } |
400 | ||
401 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) | |
402 | { | |
59725dc2 | 403 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 | 404 | struct ccid3_options_received *opt_recv; |
8c60f3fa | 405 | struct dccp_tx_hist_entry *packet; |
0740d49c | 406 | ktime_t now; |
2a1fda6f | 407 | unsigned long t_nfb; |
7dfee1a9 | 408 | u32 pinv, r_sample; |
1f2333ae | 409 | |
7c657876 ACM |
410 | /* we are only interested in ACKs */ |
411 | if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || | |
412 | DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) | |
413 | return; | |
414 | ||
415 | opt_recv = &hctx->ccid3hctx_options_received; | |
416 | ||
7c657876 | 417 | switch (hctx->ccid3hctx_state) { |
7c657876 ACM |
418 | case TFRC_SSTATE_NO_FBACK: |
419 | case TFRC_SSTATE_FBACK: | |
5c3fbb6a | 420 | /* get packet from history to look up t_recvdata */ |
8c60f3fa | 421 | packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist, |
8109b02b | 422 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
59d203f9 | 423 | if (unlikely(packet == NULL)) { |
5c3fbb6a | 424 | DCCP_WARN("%s(%p), seqno %llu(%s) doesn't exist " |
59348b19 | 425 | "in history!\n", dccp_role(sk), sk, |
59d203f9 | 426 | (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq, |
8109b02b | 427 | dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type)); |
7c657876 ACM |
428 | return; |
429 | } | |
430 | ||
1a21e49a | 431 | /* Update receive rate in units of 64 * bytes/second */ |
9e8efc82 GR |
432 | hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate; |
433 | hctx->ccid3hctx_x_recv <<= 6; | |
5c3fbb6a GR |
434 | |
435 | /* Update loss event rate */ | |
436 | pinv = opt_recv->ccid3or_loss_event_rate; | |
45393a66 | 437 | if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */ |
5c3fbb6a | 438 | hctx->ccid3hctx_p = 0; |
45393a66 | 439 | else /* can not exceed 100% */ |
8109b02b | 440 | hctx->ccid3hctx_p = 1000000 / pinv; |
5c3fbb6a | 441 | |
9823b7b5 | 442 | now = ktime_get_real(); |
5c3fbb6a GR |
443 | /* |
444 | * Calculate new round trip sample as per [RFC 3448, 4.3] by | |
8109b02b | 445 | * R_sample = (now - t_recvdata) - t_elapsed |
5c3fbb6a | 446 | */ |
3393da82 | 447 | r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, packet->dccphtx_tstamp)); |
5c3fbb6a | 448 | |
7dfee1a9 GR |
449 | /* |
450 | * Update RTT estimate by | |
7c657876 ACM |
451 | * If (No feedback recv) |
452 | * R = R_sample; | |
453 | * Else | |
454 | * R = q * R + (1 - q) * R_sample; | |
455 | * | |
456 | * q is a constant, RFC 3448 recomments 0.9 | |
457 | */ | |
458 | if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) { | |
1a21e49a GR |
459 | /* |
460 | * Larger Initial Windows [RFC 4342, sec. 5] | |
1a21e49a | 461 | */ |
a79ef76f | 462 | hctx->ccid3hctx_rtt = r_sample; |
a21f9f96 | 463 | hctx->ccid3hctx_x = rfc3390_initial_rate(sk); |
9823b7b5 | 464 | hctx->ccid3hctx_t_ld = now; |
a79ef76f | 465 | |
1266adee | 466 | ccid3_update_send_interval(hctx); |
7c657876 | 467 | |
a21f9f96 | 468 | ccid3_pr_debug("%s(%p), s=%u, MSS=%u, " |
7dfee1a9 | 469 | "R_sample=%uus, X=%u\n", dccp_role(sk), |
0f08461e | 470 | sk, hctx->ccid3hctx_s, |
1b07a95a | 471 | dccp_sk(sk)->dccps_mss_cache, r_sample, |
1a21e49a | 472 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
7c657876 | 473 | |
5c3fbb6a GR |
474 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); |
475 | } else { | |
476 | hctx->ccid3hctx_rtt = (9 * hctx->ccid3hctx_rtt + | |
7dfee1a9 | 477 | r_sample) / 10; |
7c657876 | 478 | |
ff586298 GR |
479 | /* Update sending rate (step 4 of [RFC 3448, 4.3]) */ |
480 | if (hctx->ccid3hctx_p > 0) | |
481 | hctx->ccid3hctx_x_calc = | |
482 | tfrc_calc_x(hctx->ccid3hctx_s, | |
483 | hctx->ccid3hctx_rtt, | |
484 | hctx->ccid3hctx_p); | |
aa97efd9 | 485 | ccid3_hc_tx_update_x(sk, &now); |
7c657876 | 486 | |
7dfee1a9 | 487 | ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, " |
8109b02b ACM |
488 | "p=%u, X_calc=%u, X_recv=%u, X=%u\n", |
489 | dccp_role(sk), | |
7dfee1a9 | 490 | sk, hctx->ccid3hctx_rtt, r_sample, |
5c3fbb6a GR |
491 | hctx->ccid3hctx_s, hctx->ccid3hctx_p, |
492 | hctx->ccid3hctx_x_calc, | |
9e8efc82 | 493 | (unsigned)(hctx->ccid3hctx_x_recv >> 6), |
8109b02b | 494 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
7c657876 ACM |
495 | } |
496 | ||
497 | /* unschedule no feedback timer */ | |
498 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); | |
499 | ||
7c657876 | 500 | /* remove all packets older than the one acked from history */ |
8c60f3fa ACM |
501 | dccp_tx_hist_purge_older(ccid3_tx_hist, |
502 | &hctx->ccid3hctx_hist, packet); | |
c530cfb1 | 503 | /* |
8109b02b ACM |
504 | * As we have calculated new ipi, delta, t_nom it is possible |
505 | * that we now can send a packet, so wake up dccp_wait_for_ccid | |
c530cfb1 ACM |
506 | */ |
507 | sk->sk_write_space(sk); | |
8c60f3fa | 508 | |
8a508ac2 GR |
509 | /* |
510 | * Update timeout interval for the nofeedback timer. | |
511 | * We use a configuration option to increase the lower bound. | |
8109b02b ACM |
512 | * This can help avoid triggering the nofeedback timer too |
513 | * often ('spinning') on LANs with small RTTs. | |
8a508ac2 | 514 | */ |
5d0dbc4a | 515 | hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt, |
8a508ac2 | 516 | CONFIG_IP_DCCP_CCID3_RTO * |
8109b02b | 517 | (USEC_PER_SEC/1000)); |
1f2333ae ACM |
518 | /* |
519 | * Schedule no feedback timer to expire in | |
8a508ac2 | 520 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
1f2333ae | 521 | */ |
8a508ac2 | 522 | t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi); |
7c657876 | 523 | |
a9672411 | 524 | ccid3_pr_debug("%s(%p), Scheduled no feedback timer to " |
8109b02b ACM |
525 | "expire in %lu jiffies (%luus)\n", |
526 | dccp_role(sk), | |
a9672411 GR |
527 | sk, usecs_to_jiffies(t_nfb), t_nfb); |
528 | ||
529 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | |
2a1fda6f | 530 | jiffies + usecs_to_jiffies(t_nfb)); |
7c657876 ACM |
531 | |
532 | /* set idle flag */ | |
bf58a381 | 533 | hctx->ccid3hctx_idle = 1; |
7c657876 | 534 | break; |
151a9931 | 535 | case TFRC_SSTATE_NO_SENT: /* fall through */ |
5e19e3fc | 536 | case TFRC_SSTATE_TERM: /* ignore feedback when closing */ |
7c657876 ACM |
537 | break; |
538 | } | |
539 | } | |
540 | ||
7c657876 | 541 | static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, |
1f2333ae ACM |
542 | unsigned char len, u16 idx, |
543 | unsigned char *value) | |
7c657876 ACM |
544 | { |
545 | int rc = 0; | |
59725dc2 ACM |
546 | const struct dccp_sock *dp = dccp_sk(sk); |
547 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); | |
7c657876 | 548 | struct ccid3_options_received *opt_recv; |
76fd1e87 | 549 | __be32 opt_val; |
7c657876 | 550 | |
7c657876 ACM |
551 | opt_recv = &hctx->ccid3hctx_options_received; |
552 | ||
553 | if (opt_recv->ccid3or_seqno != dp->dccps_gsr) { | |
554 | opt_recv->ccid3or_seqno = dp->dccps_gsr; | |
555 | opt_recv->ccid3or_loss_event_rate = ~0; | |
556 | opt_recv->ccid3or_loss_intervals_idx = 0; | |
557 | opt_recv->ccid3or_loss_intervals_len = 0; | |
558 | opt_recv->ccid3or_receive_rate = 0; | |
559 | } | |
560 | ||
561 | switch (option) { | |
562 | case TFRC_OPT_LOSS_EVENT_RATE: | |
59d203f9 | 563 | if (unlikely(len != 4)) { |
a9672411 | 564 | DCCP_WARN("%s(%p), invalid len %d " |
59348b19 GR |
565 | "for TFRC_OPT_LOSS_EVENT_RATE\n", |
566 | dccp_role(sk), sk, len); | |
7c657876 ACM |
567 | rc = -EINVAL; |
568 | } else { | |
76fd1e87 GR |
569 | opt_val = get_unaligned((__be32 *)value); |
570 | opt_recv->ccid3or_loss_event_rate = ntohl(opt_val); | |
a9672411 | 571 | ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n", |
7c657876 ACM |
572 | dccp_role(sk), sk, |
573 | opt_recv->ccid3or_loss_event_rate); | |
574 | } | |
575 | break; | |
576 | case TFRC_OPT_LOSS_INTERVALS: | |
577 | opt_recv->ccid3or_loss_intervals_idx = idx; | |
578 | opt_recv->ccid3or_loss_intervals_len = len; | |
a9672411 | 579 | ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n", |
7c657876 ACM |
580 | dccp_role(sk), sk, |
581 | opt_recv->ccid3or_loss_intervals_idx, | |
582 | opt_recv->ccid3or_loss_intervals_len); | |
583 | break; | |
584 | case TFRC_OPT_RECEIVE_RATE: | |
59d203f9 | 585 | if (unlikely(len != 4)) { |
a9672411 | 586 | DCCP_WARN("%s(%p), invalid len %d " |
59348b19 GR |
587 | "for TFRC_OPT_RECEIVE_RATE\n", |
588 | dccp_role(sk), sk, len); | |
7c657876 ACM |
589 | rc = -EINVAL; |
590 | } else { | |
76fd1e87 GR |
591 | opt_val = get_unaligned((__be32 *)value); |
592 | opt_recv->ccid3or_receive_rate = ntohl(opt_val); | |
a9672411 | 593 | ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n", |
7c657876 ACM |
594 | dccp_role(sk), sk, |
595 | opt_recv->ccid3or_receive_rate); | |
596 | } | |
597 | break; | |
598 | } | |
599 | ||
600 | return rc; | |
601 | } | |
602 | ||
91f0ebf7 | 603 | static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk) |
7c657876 | 604 | { |
91f0ebf7 | 605 | struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid); |
7c657876 | 606 | |
7c657876 ACM |
607 | hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT; |
608 | INIT_LIST_HEAD(&hctx->ccid3hctx_hist); | |
b24b8a24 PE |
609 | setup_timer(&hctx->ccid3hctx_no_feedback_timer, |
610 | ccid3_hc_tx_no_feedback_timer, (unsigned long)sk); | |
7c657876 ACM |
611 | |
612 | return 0; | |
613 | } | |
614 | ||
615 | static void ccid3_hc_tx_exit(struct sock *sk) | |
616 | { | |
59725dc2 | 617 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
7c657876 | 618 | |
7c657876 ACM |
619 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM); |
620 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); | |
621 | ||
622 | /* Empty packet history */ | |
8c60f3fa | 623 | dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist); |
7c657876 ACM |
624 | } |
625 | ||
9bf17475 GR |
626 | static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) |
627 | { | |
2e86908f | 628 | struct ccid3_hc_tx_sock *hctx; |
9bf17475 GR |
629 | |
630 | /* Listen socks doesn't have a private CCID block */ | |
631 | if (sk->sk_state == DCCP_LISTEN) | |
632 | return; | |
633 | ||
2e86908f | 634 | hctx = ccid3_hc_tx_sk(sk); |
9bf17475 GR |
635 | info->tcpi_rto = hctx->ccid3hctx_t_rto; |
636 | info->tcpi_rtt = hctx->ccid3hctx_rtt; | |
637 | } | |
638 | ||
639 | static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, | |
640 | u32 __user *optval, int __user *optlen) | |
641 | { | |
2e86908f | 642 | const struct ccid3_hc_tx_sock *hctx; |
9bf17475 GR |
643 | const void *val; |
644 | ||
645 | /* Listen socks doesn't have a private CCID block */ | |
646 | if (sk->sk_state == DCCP_LISTEN) | |
647 | return -EINVAL; | |
648 | ||
2e86908f | 649 | hctx = ccid3_hc_tx_sk(sk); |
9bf17475 GR |
650 | switch (optname) { |
651 | case DCCP_SOCKOPT_CCID_TX_INFO: | |
652 | if (len < sizeof(hctx->ccid3hctx_tfrc)) | |
653 | return -EINVAL; | |
654 | len = sizeof(hctx->ccid3hctx_tfrc); | |
655 | val = &hctx->ccid3hctx_tfrc; | |
656 | break; | |
657 | default: | |
658 | return -ENOPROTOOPT; | |
659 | } | |
660 | ||
661 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) | |
662 | return -EFAULT; | |
663 | ||
664 | return 0; | |
665 | } | |
666 | ||
7c657876 | 667 | /* |
9bf17475 | 668 | * Receiver Half-Connection Routines |
7c657876 | 669 | */ |
56724aa4 | 670 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
7c657876 ACM |
671 | static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) |
672 | { | |
673 | static char *ccid3_rx_state_names[] = { | |
674 | [TFRC_RSTATE_NO_DATA] = "NO_DATA", | |
675 | [TFRC_RSTATE_DATA] = "DATA", | |
676 | [TFRC_RSTATE_TERM] = "TERM", | |
677 | }; | |
678 | ||
679 | return ccid3_rx_state_names[state]; | |
680 | } | |
681 | #endif | |
682 | ||
c25a18ba ACM |
683 | static void ccid3_hc_rx_set_state(struct sock *sk, |
684 | enum ccid3_hc_rx_states state) | |
7c657876 | 685 | { |
59725dc2 | 686 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 ACM |
687 | enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state; |
688 | ||
689 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | |
1f2333ae ACM |
690 | dccp_role(sk), sk, ccid3_rx_state_name(oldstate), |
691 | ccid3_rx_state_name(state)); | |
7c657876 ACM |
692 | WARN_ON(state == oldstate); |
693 | hcrx->ccid3hcrx_state = state; | |
694 | } | |
695 | ||
78ad713d GR |
696 | static inline void ccid3_hc_rx_update_s(struct ccid3_hc_rx_sock *hcrx, int len) |
697 | { | |
698 | if (unlikely(len == 0)) /* don't update on empty packets (e.g. ACKs) */ | |
699 | ccid3_pr_debug("Packet payload length is 0 - not updating\n"); | |
700 | else | |
701 | hcrx->ccid3hcrx_s = hcrx->ccid3hcrx_s == 0 ? len : | |
702 | (9 * hcrx->ccid3hcrx_s + len) / 10; | |
703 | } | |
704 | ||
7c657876 ACM |
705 | static void ccid3_hc_rx_send_feedback(struct sock *sk) |
706 | { | |
59725dc2 | 707 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 | 708 | struct dccp_sock *dp = dccp_sk(sk); |
8c60f3fa | 709 | struct dccp_rx_hist_entry *packet; |
e7c23357 | 710 | ktime_t now; |
0f9e5b57 | 711 | suseconds_t delta; |
7c657876 | 712 | |
a9672411 | 713 | ccid3_pr_debug("%s(%p) - entry \n", dccp_role(sk), sk); |
7c657876 | 714 | |
e7a81c6d | 715 | now = ktime_get_real(); |
b6ee3d4a | 716 | |
7c657876 ACM |
717 | switch (hcrx->ccid3hcrx_state) { |
718 | case TFRC_RSTATE_NO_DATA: | |
719 | hcrx->ccid3hcrx_x_recv = 0; | |
720 | break; | |
0f9e5b57 | 721 | case TFRC_RSTATE_DATA: |
e7a81c6d ACM |
722 | delta = ktime_us_delta(now, |
723 | hcrx->ccid3hcrx_tstamp_last_feedback); | |
0f9e5b57 | 724 | DCCP_BUG_ON(delta < 0); |
b9039a2a GR |
725 | hcrx->ccid3hcrx_x_recv = |
726 | scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta); | |
7c657876 | 727 | break; |
59348b19 | 728 | case TFRC_RSTATE_TERM: |
a9672411 | 729 | DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); |
7c657876 ACM |
730 | return; |
731 | } | |
732 | ||
8c60f3fa | 733 | packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist); |
59d203f9 | 734 | if (unlikely(packet == NULL)) { |
a9672411 | 735 | DCCP_WARN("%s(%p), no data packet in history!\n", |
59348b19 | 736 | dccp_role(sk), sk); |
7c657876 ACM |
737 | return; |
738 | } | |
739 | ||
b6ee3d4a | 740 | hcrx->ccid3hcrx_tstamp_last_feedback = now; |
66a377c5 | 741 | hcrx->ccid3hcrx_ccval_last_counter = packet->dccphrx_ccval; |
7c657876 ACM |
742 | hcrx->ccid3hcrx_bytes_recv = 0; |
743 | ||
0f9e5b57 | 744 | /* Elapsed time information [RFC 4340, 13.2] in units of 10 * usecs */ |
e7c23357 | 745 | delta = ktime_us_delta(now, packet->dccphrx_tstamp); |
0f9e5b57 GR |
746 | DCCP_BUG_ON(delta < 0); |
747 | hcrx->ccid3hcrx_elapsed_time = delta / 10; | |
45393a66 | 748 | |
7c657876 | 749 | if (hcrx->ccid3hcrx_p == 0) |
45393a66 GR |
750 | hcrx->ccid3hcrx_pinv = ~0U; /* see RFC 4342, 8.5 */ |
751 | else if (hcrx->ccid3hcrx_p > 1000000) { | |
752 | DCCP_WARN("p (%u) > 100%%\n", hcrx->ccid3hcrx_p); | |
753 | hcrx->ccid3hcrx_pinv = 1; /* use 100% in this case */ | |
754 | } else | |
7c657876 | 755 | hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p; |
45393a66 | 756 | |
507d37cf | 757 | dp->dccps_hc_rx_insert_options = 1; |
7c657876 ACM |
758 | dccp_send_ack(sk); |
759 | } | |
760 | ||
2d0817d1 | 761 | static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) |
7c657876 | 762 | { |
2e86908f | 763 | const struct ccid3_hc_rx_sock *hcrx; |
60fe62e7 | 764 | __be32 x_recv, pinv; |
7c657876 | 765 | |
59d203f9 | 766 | if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) |
2d0817d1 | 767 | return 0; |
7c657876 | 768 | |
2e86908f | 769 | hcrx = ccid3_hc_rx_sk(sk); |
66a377c5 | 770 | DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_ccval_last_counter; |
4fded33b ACM |
771 | |
772 | if (dccp_packet_without_ack(skb)) | |
2d0817d1 ACM |
773 | return 0; |
774 | ||
4fded33b ACM |
775 | x_recv = htonl(hcrx->ccid3hcrx_x_recv); |
776 | pinv = htonl(hcrx->ccid3hcrx_pinv); | |
2d0817d1 ACM |
777 | |
778 | if ((hcrx->ccid3hcrx_elapsed_time != 0 && | |
779 | dccp_insert_option_elapsed_time(sk, skb, | |
780 | hcrx->ccid3hcrx_elapsed_time)) || | |
781 | dccp_insert_option_timestamp(sk, skb) || | |
782 | dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE, | |
8109b02b | 783 | &pinv, sizeof(pinv)) || |
2d0817d1 | 784 | dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE, |
8109b02b | 785 | &x_recv, sizeof(x_recv))) |
2d0817d1 ACM |
786 | return -1; |
787 | ||
788 | return 0; | |
7c657876 ACM |
789 | } |
790 | ||
66a377c5 | 791 | static int ccid3_hc_rx_detect_loss(struct sock *sk, |
c9eaf173 | 792 | struct dccp_rx_hist_entry *packet) |
7c657876 | 793 | { |
59725dc2 | 794 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
8109b02b ACM |
795 | struct dccp_rx_hist_entry *rx_hist = |
796 | dccp_rx_hist_head(&hcrx->ccid3hcrx_hist); | |
66a377c5 IM |
797 | u64 seqno = packet->dccphrx_seqno; |
798 | u64 tmp_seqno; | |
799 | int loss = 0; | |
800 | u8 ccval; | |
801 | ||
802 | ||
803 | tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss; | |
804 | ||
805 | if (!rx_hist || | |
806 | follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) { | |
807 | hcrx->ccid3hcrx_seqno_nonloss = seqno; | |
808 | hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval; | |
809 | goto detect_out; | |
810 | } | |
811 | ||
7c657876 | 812 | |
66a377c5 IM |
813 | while (dccp_delta_seqno(hcrx->ccid3hcrx_seqno_nonloss, seqno) |
814 | > TFRC_RECV_NUM_LATE_LOSS) { | |
815 | loss = 1; | |
cc4d6a3a | 816 | dccp_li_update_li(sk, |
cc0a910b ACM |
817 | &hcrx->ccid3hcrx_li_hist, |
818 | &hcrx->ccid3hcrx_hist, | |
e7c23357 | 819 | hcrx->ccid3hcrx_tstamp_last_feedback, |
cc0a910b ACM |
820 | hcrx->ccid3hcrx_s, |
821 | hcrx->ccid3hcrx_bytes_recv, | |
822 | hcrx->ccid3hcrx_x_recv, | |
823 | hcrx->ccid3hcrx_seqno_nonloss, | |
824 | hcrx->ccid3hcrx_ccval_nonloss); | |
66a377c5 IM |
825 | tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss; |
826 | dccp_inc_seqno(&tmp_seqno); | |
827 | hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno; | |
828 | dccp_inc_seqno(&tmp_seqno); | |
829 | while (dccp_rx_hist_find_entry(&hcrx->ccid3hcrx_hist, | |
830 | tmp_seqno, &ccval)) { | |
8109b02b | 831 | hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno; |
66a377c5 IM |
832 | hcrx->ccid3hcrx_ccval_nonloss = ccval; |
833 | dccp_inc_seqno(&tmp_seqno); | |
834 | } | |
835 | } | |
836 | ||
837 | /* FIXME - this code could be simplified with above while */ | |
838 | /* but works at moment */ | |
839 | if (follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) { | |
840 | hcrx->ccid3hcrx_seqno_nonloss = seqno; | |
841 | hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval; | |
842 | } | |
843 | ||
844 | detect_out: | |
845 | dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist, | |
846 | &hcrx->ccid3hcrx_li_hist, packet, | |
847 | hcrx->ccid3hcrx_seqno_nonloss); | |
848 | return loss; | |
7c657876 ACM |
849 | } |
850 | ||
7c657876 ACM |
851 | static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) |
852 | { | |
59725dc2 | 853 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
4fded33b | 854 | const struct dccp_options_received *opt_recv; |
8c60f3fa | 855 | struct dccp_rx_hist_entry *packet; |
7dfee1a9 | 856 | u32 p_prev, r_sample, rtt_prev; |
78ad713d | 857 | int loss, payload_size; |
9823b7b5 | 858 | ktime_t now; |
1f2333ae | 859 | |
59725dc2 | 860 | opt_recv = &dccp_sk(sk)->dccps_options_received; |
4fded33b | 861 | |
7c657876 ACM |
862 | switch (DCCP_SKB_CB(skb)->dccpd_type) { |
863 | case DCCP_PKT_ACK: | |
864 | if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) | |
865 | return; | |
9823b7b5 | 866 | case DCCP_PKT_DATAACK: |
4fded33b | 867 | if (opt_recv->dccpor_timestamp_echo == 0) |
7c657876 | 868 | break; |
3393da82 | 869 | r_sample = dccp_timestamp() - opt_recv->dccpor_timestamp_echo; |
66a377c5 | 870 | rtt_prev = hcrx->ccid3hcrx_rtt; |
3393da82 | 871 | r_sample = dccp_sample_rtt(sk, 10 * r_sample); |
b3a3077d ACM |
872 | |
873 | if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) | |
874 | hcrx->ccid3hcrx_rtt = r_sample; | |
875 | else | |
876 | hcrx->ccid3hcrx_rtt = (hcrx->ccid3hcrx_rtt * 9) / 10 + | |
877 | r_sample / 10; | |
878 | ||
66a377c5 | 879 | if (rtt_prev != hcrx->ccid3hcrx_rtt) |
a9672411 GR |
880 | ccid3_pr_debug("%s(%p), New RTT=%uus, elapsed time=%u\n", |
881 | dccp_role(sk), sk, hcrx->ccid3hcrx_rtt, | |
4fded33b | 882 | opt_recv->dccpor_elapsed_time); |
7c657876 ACM |
883 | break; |
884 | case DCCP_PKT_DATA: | |
885 | break; | |
59d203f9 | 886 | default: /* We're not interested in other packet types, move along */ |
7c657876 ACM |
887 | return; |
888 | } | |
889 | ||
e7c23357 | 890 | packet = dccp_rx_hist_entry_new(ccid3_rx_hist, opt_recv->dccpor_ndp, |
54e6ecb2 | 891 | skb, GFP_ATOMIC); |
59d203f9 | 892 | if (unlikely(packet == NULL)) { |
a9672411 | 893 | DCCP_WARN("%s(%p), Not enough mem to add rx packet " |
59348b19 | 894 | "to history, consider it lost!\n", dccp_role(sk), sk); |
7c657876 ACM |
895 | return; |
896 | } | |
897 | ||
66a377c5 | 898 | loss = ccid3_hc_rx_detect_loss(sk, packet); |
7c657876 ACM |
899 | |
900 | if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK) | |
901 | return; | |
902 | ||
78ad713d GR |
903 | payload_size = skb->len - dccp_hdr(skb)->dccph_doff * 4; |
904 | ccid3_hc_rx_update_s(hcrx, payload_size); | |
905 | ||
7c657876 ACM |
906 | switch (hcrx->ccid3hcrx_state) { |
907 | case TFRC_RSTATE_NO_DATA: | |
a9672411 GR |
908 | ccid3_pr_debug("%s(%p, state=%s), skb=%p, sending initial " |
909 | "feedback\n", dccp_role(sk), sk, | |
1f2333ae | 910 | dccp_state_name(sk->sk_state), skb); |
7c657876 ACM |
911 | ccid3_hc_rx_send_feedback(sk); |
912 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); | |
913 | return; | |
9823b7b5 | 914 | case TFRC_RSTATE_DATA: |
78ad713d | 915 | hcrx->ccid3hcrx_bytes_recv += payload_size; |
66a377c5 | 916 | if (loss) |
b6ee3d4a ACM |
917 | break; |
918 | ||
1faf0a1f ACM |
919 | now = ktime_get_real(); |
920 | if ((ktime_us_delta(now, hcrx->ccid3hcrx_tstamp_last_ack) - | |
921 | (s64)hcrx->ccid3hcrx_rtt) >= 0) { | |
b6ee3d4a ACM |
922 | hcrx->ccid3hcrx_tstamp_last_ack = now; |
923 | ccid3_hc_rx_send_feedback(sk); | |
7c657876 | 924 | } |
b6ee3d4a | 925 | return; |
59348b19 | 926 | case TFRC_RSTATE_TERM: |
a9672411 | 927 | DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); |
7c657876 ACM |
928 | return; |
929 | } | |
930 | ||
931 | /* Dealing with packet loss */ | |
a9672411 | 932 | ccid3_pr_debug("%s(%p, state=%s), data loss! Reacting...\n", |
4fded33b | 933 | dccp_role(sk), sk, dccp_state_name(sk->sk_state)); |
7c657876 | 934 | |
7c657876 | 935 | p_prev = hcrx->ccid3hcrx_p; |
c9eaf173 | 936 | |
7c657876 | 937 | /* Calculate loss event rate */ |
c0996660 IM |
938 | if (!list_empty(&hcrx->ccid3hcrx_li_hist)) { |
939 | u32 i_mean = dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist); | |
940 | ||
7c657876 | 941 | /* Scaling up by 1000000 as fixed decimal */ |
c0996660 IM |
942 | if (i_mean != 0) |
943 | hcrx->ccid3hcrx_p = 1000000 / i_mean; | |
59348b19 GR |
944 | } else |
945 | DCCP_BUG("empty loss history"); | |
7c657876 ACM |
946 | |
947 | if (hcrx->ccid3hcrx_p > p_prev) { | |
948 | ccid3_hc_rx_send_feedback(sk); | |
949 | return; | |
950 | } | |
951 | } | |
952 | ||
91f0ebf7 | 953 | static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk) |
7c657876 | 954 | { |
91f0ebf7 | 955 | struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid); |
7c657876 | 956 | |
a9672411 | 957 | ccid3_pr_debug("entry\n"); |
7c657876 | 958 | |
7c657876 ACM |
959 | hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA; |
960 | INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist); | |
ae6706f0 | 961 | INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist); |
1faf0a1f | 962 | hcrx->ccid3hcrx_tstamp_last_feedback = |
e7a81c6d | 963 | hcrx->ccid3hcrx_tstamp_last_ack = ktime_get_real(); |
7c657876 ACM |
964 | return 0; |
965 | } | |
966 | ||
967 | static void ccid3_hc_rx_exit(struct sock *sk) | |
968 | { | |
59725dc2 | 969 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
7c657876 | 970 | |
7c657876 ACM |
971 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM); |
972 | ||
973 | /* Empty packet history */ | |
8c60f3fa | 974 | dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist); |
7c657876 ACM |
975 | |
976 | /* Empty loss interval history */ | |
cc4d6a3a | 977 | dccp_li_hist_purge(&hcrx->ccid3hcrx_li_hist); |
7c657876 ACM |
978 | } |
979 | ||
2babe1f6 ACM |
980 | static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) |
981 | { | |
2e86908f | 982 | const struct ccid3_hc_rx_sock *hcrx; |
2babe1f6 | 983 | |
59c2353d ACM |
984 | /* Listen socks doesn't have a private CCID block */ |
985 | if (sk->sk_state == DCCP_LISTEN) | |
986 | return; | |
987 | ||
2e86908f | 988 | hcrx = ccid3_hc_rx_sk(sk); |
8109b02b ACM |
989 | info->tcpi_ca_state = hcrx->ccid3hcrx_state; |
990 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; | |
991 | info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt; | |
2babe1f6 ACM |
992 | } |
993 | ||
88f964db ACM |
994 | static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, |
995 | u32 __user *optval, int __user *optlen) | |
996 | { | |
2e86908f | 997 | const struct ccid3_hc_rx_sock *hcrx; |
88f964db | 998 | const void *val; |
c9eaf173 | 999 | |
88f964db ACM |
1000 | /* Listen socks doesn't have a private CCID block */ |
1001 | if (sk->sk_state == DCCP_LISTEN) | |
1002 | return -EINVAL; | |
1003 | ||
2e86908f | 1004 | hcrx = ccid3_hc_rx_sk(sk); |
88f964db ACM |
1005 | switch (optname) { |
1006 | case DCCP_SOCKOPT_CCID_RX_INFO: | |
1007 | if (len < sizeof(hcrx->ccid3hcrx_tfrc)) | |
1008 | return -EINVAL; | |
1009 | len = sizeof(hcrx->ccid3hcrx_tfrc); | |
1010 | val = &hcrx->ccid3hcrx_tfrc; | |
1011 | break; | |
1012 | default: | |
1013 | return -ENOPROTOOPT; | |
1014 | } | |
1015 | ||
1016 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) | |
1017 | return -EFAULT; | |
1018 | ||
1019 | return 0; | |
1020 | } | |
1021 | ||
91f0ebf7 | 1022 | static struct ccid_operations ccid3 = { |
3dd9a7c3 | 1023 | .ccid_id = DCCPC_CCID3, |
7c657876 ACM |
1024 | .ccid_name = "ccid3", |
1025 | .ccid_owner = THIS_MODULE, | |
91f0ebf7 | 1026 | .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock), |
7c657876 ACM |
1027 | .ccid_hc_tx_init = ccid3_hc_tx_init, |
1028 | .ccid_hc_tx_exit = ccid3_hc_tx_exit, | |
1029 | .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, | |
1030 | .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, | |
1031 | .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, | |
7c657876 | 1032 | .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, |
91f0ebf7 | 1033 | .ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock), |
7c657876 ACM |
1034 | .ccid_hc_rx_init = ccid3_hc_rx_init, |
1035 | .ccid_hc_rx_exit = ccid3_hc_rx_exit, | |
1036 | .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, | |
1037 | .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, | |
2babe1f6 ACM |
1038 | .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, |
1039 | .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, | |
88f964db ACM |
1040 | .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt, |
1041 | .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt, | |
7c657876 | 1042 | }; |
8109b02b | 1043 | |
56724aa4 | 1044 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
042d18f9 | 1045 | module_param(ccid3_debug, bool, 0444); |
7c657876 | 1046 | MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); |
56724aa4 | 1047 | #endif |
7c657876 ACM |
1048 | |
1049 | static __init int ccid3_module_init(void) | |
1050 | { | |
8c60f3fa | 1051 | int rc = -ENOBUFS; |
7c657876 | 1052 | |
8c60f3fa ACM |
1053 | ccid3_rx_hist = dccp_rx_hist_new("ccid3"); |
1054 | if (ccid3_rx_hist == NULL) | |
7c657876 ACM |
1055 | goto out; |
1056 | ||
8c60f3fa ACM |
1057 | ccid3_tx_hist = dccp_tx_hist_new("ccid3"); |
1058 | if (ccid3_tx_hist == NULL) | |
1059 | goto out_free_rx; | |
7c657876 | 1060 | |
7c657876 | 1061 | rc = ccid_register(&ccid3); |
8109b02b | 1062 | if (rc != 0) |
cc4d6a3a | 1063 | goto out_free_tx; |
7c657876 ACM |
1064 | out: |
1065 | return rc; | |
8c60f3fa | 1066 | |
8c60f3fa ACM |
1067 | out_free_tx: |
1068 | dccp_tx_hist_delete(ccid3_tx_hist); | |
1069 | ccid3_tx_hist = NULL; | |
1070 | out_free_rx: | |
1071 | dccp_rx_hist_delete(ccid3_rx_hist); | |
1072 | ccid3_rx_hist = NULL; | |
7c657876 ACM |
1073 | goto out; |
1074 | } | |
1075 | module_init(ccid3_module_init); | |
1076 | ||
1077 | static __exit void ccid3_module_exit(void) | |
1078 | { | |
1079 | ccid_unregister(&ccid3); | |
1080 | ||
8c60f3fa ACM |
1081 | if (ccid3_tx_hist != NULL) { |
1082 | dccp_tx_hist_delete(ccid3_tx_hist); | |
1083 | ccid3_tx_hist = NULL; | |
7c657876 | 1084 | } |
8c60f3fa ACM |
1085 | if (ccid3_rx_hist != NULL) { |
1086 | dccp_rx_hist_delete(ccid3_rx_hist); | |
1087 | ccid3_rx_hist = NULL; | |
7c657876 | 1088 | } |
7c657876 ACM |
1089 | } |
1090 | module_exit(ccid3_module_exit); | |
1091 | ||
e6bccd35 | 1092 | MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, " |
1f2333ae | 1093 | "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); |
7c657876 ACM |
1094 | MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); |
1095 | MODULE_LICENSE("GPL"); | |
1096 | MODULE_ALIAS("net-dccp-ccid-3"); |