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Commit | Line | Data |
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7c657876 | 1 | /* |
954c2db8 | 2 | * Copyright (c) 2007 The University of Aberdeen, Scotland, UK |
b2f41ff4 IM |
3 | * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. |
4 | * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz> | |
7c657876 ACM |
5 | * |
6 | * An implementation of the DCCP protocol | |
7 | * | |
8 | * This code has been developed by the University of Waikato WAND | |
9 | * research group. For further information please see http://www.wand.net.nz/ | |
7c657876 ACM |
10 | * |
11 | * This code also uses code from Lulea University, rereleased as GPL by its | |
12 | * authors: | |
13 | * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon | |
14 | * | |
15 | * Changes to meet Linux coding standards, to make it meet latest ccid3 draft | |
16 | * and to make it work as a loadable module in the DCCP stack written by | |
17 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br>. | |
18 | * | |
19 | * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> | |
20 | * | |
21 | * This program is free software; you can redistribute it and/or modify | |
22 | * it under the terms of the GNU General Public License as published by | |
23 | * the Free Software Foundation; either version 2 of the License, or | |
24 | * (at your option) any later version. | |
25 | * | |
26 | * This program is distributed in the hope that it will be useful, | |
27 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
28 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
29 | * GNU General Public License for more details. | |
30 | * | |
31 | * You should have received a copy of the GNU General Public License | |
32 | * along with this program; if not, write to the Free Software | |
33 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
34 | */ | |
7c657876 ACM |
35 | #include "../dccp.h" |
36 | #include "ccid3.h" | |
37 | ||
76fd1e87 GR |
38 | #include <asm/unaligned.h> |
39 | ||
56724aa4 | 40 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
eb939922 | 41 | static bool ccid3_debug; |
56724aa4 | 42 | #define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a) |
7c657876 ACM |
43 | #else |
44 | #define ccid3_pr_debug(format, a...) | |
45 | #endif | |
46 | ||
9bf17475 GR |
47 | /* |
48 | * Transmitter Half-Connection Routines | |
49 | */ | |
410e27a4 GR |
50 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
51 | static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) | |
52 | { | |
36cbd3dc | 53 | static const char *const ccid3_state_names[] = { |
410e27a4 GR |
54 | [TFRC_SSTATE_NO_SENT] = "NO_SENT", |
55 | [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", | |
56 | [TFRC_SSTATE_FBACK] = "FBACK", | |
410e27a4 GR |
57 | }; |
58 | ||
59 | return ccid3_state_names[state]; | |
60 | } | |
61 | #endif | |
62 | ||
63 | static void ccid3_hc_tx_set_state(struct sock *sk, | |
64 | enum ccid3_hc_tx_states state) | |
65 | { | |
996ccf49 GR |
66 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
67 | enum ccid3_hc_tx_states oldstate = hc->tx_state; | |
410e27a4 GR |
68 | |
69 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | |
70 | dccp_role(sk), sk, ccid3_tx_state_name(oldstate), | |
71 | ccid3_tx_state_name(state)); | |
72 | WARN_ON(state == oldstate); | |
996ccf49 | 73 | hc->tx_state = state; |
410e27a4 | 74 | } |
7c657876 | 75 | |
a21f9f96 | 76 | /* |
6c08b2cf GR |
77 | * Compute the initial sending rate X_init in the manner of RFC 3390: |
78 | * | |
410e27a4 | 79 | * X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT |
6c08b2cf | 80 | * |
410e27a4 GR |
81 | * Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis |
82 | * (rev-02) clarifies the use of RFC 3390 with regard to the above formula. | |
a21f9f96 GR |
83 | * For consistency with other parts of the code, X_init is scaled by 2^6. |
84 | */ | |
85 | static inline u64 rfc3390_initial_rate(struct sock *sk) | |
86 | { | |
996ccf49 GR |
87 | const struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
88 | const __u32 w_init = clamp_t(__u32, 4380U, 2 * hc->tx_s, 4 * hc->tx_s); | |
a21f9f96 | 89 | |
996ccf49 | 90 | return scaled_div(w_init << 6, hc->tx_rtt); |
a21f9f96 GR |
91 | } |
92 | ||
20cbd3e1 GR |
93 | /** |
94 | * ccid3_update_send_interval - Calculate new t_ipi = s / X_inst | |
95 | * This respects the granularity of X_inst (64 * bytes/second). | |
17893bc1 | 96 | */ |
996ccf49 | 97 | static void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hc) |
7c657876 | 98 | { |
996ccf49 | 99 | hc->tx_t_ipi = scaled_div32(((u64)hc->tx_s) << 6, hc->tx_x); |
410e27a4 | 100 | |
20cbd3e1 GR |
101 | ccid3_pr_debug("t_ipi=%u, s=%u, X=%u\n", hc->tx_t_ipi, |
102 | hc->tx_s, (unsigned)(hc->tx_x >> 6)); | |
7c657876 | 103 | } |
aa97efd9 | 104 | |
996ccf49 | 105 | static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hc, ktime_t now) |
a5358fdc | 106 | { |
996ccf49 | 107 | u32 delta = ktime_us_delta(now, hc->tx_t_last_win_count); |
a5358fdc | 108 | |
996ccf49 | 109 | return delta / hc->tx_rtt; |
a5358fdc GR |
110 | } |
111 | ||
aa97efd9 GR |
112 | /** |
113 | * ccid3_hc_tx_update_x - Update allowed sending rate X | |
114 | * @stamp: most recent time if available - can be left NULL. | |
115 | * This function tracks draft rfc3448bis, check there for latest details. | |
5c3fbb6a | 116 | * |
1a21e49a GR |
117 | * Note: X and X_recv are both stored in units of 64 * bytes/second, to support |
118 | * fine-grained resolution of sending rates. This requires scaling by 2^6 | |
119 | * throughout the code. Only X_calc is unscaled (in bytes/second). | |
120 | * | |
1a21e49a | 121 | */ |
aa97efd9 | 122 | static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp) |
7c657876 | 123 | { |
996ccf49 GR |
124 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
125 | __u64 min_rate = 2 * hc->tx_x_recv; | |
126 | const __u64 old_x = hc->tx_x; | |
52515e77 | 127 | ktime_t now = stamp ? *stamp : ktime_get_real(); |
7c657876 | 128 | |
0c150efb GR |
129 | /* |
130 | * Handle IDLE periods: do not reduce below RFC3390 initial sending rate | |
a5358fdc GR |
131 | * when idling [RFC 4342, 5.1]. Definition of idling is from rfc3448bis: |
132 | * a sender is idle if it has not sent anything over a 2-RTT-period. | |
0c150efb GR |
133 | * For consistency with X and X_recv, min_rate is also scaled by 2^6. |
134 | */ | |
996ccf49 | 135 | if (ccid3_hc_tx_idle_rtt(hc, now) >= 2) { |
0c150efb | 136 | min_rate = rfc3390_initial_rate(sk); |
996ccf49 | 137 | min_rate = max(min_rate, 2 * hc->tx_x_recv); |
0c150efb GR |
138 | } |
139 | ||
996ccf49 | 140 | if (hc->tx_p > 0) { |
1a21e49a | 141 | |
996ccf49 GR |
142 | hc->tx_x = min(((__u64)hc->tx_x_calc) << 6, min_rate); |
143 | hc->tx_x = max(hc->tx_x, (((__u64)hc->tx_s) << 6) / TFRC_T_MBI); | |
a79ef76f | 144 | |
996ccf49 | 145 | } else if (ktime_us_delta(now, hc->tx_t_ld) - (s64)hc->tx_rtt >= 0) { |
ac198ea8 | 146 | |
996ccf49 GR |
147 | hc->tx_x = min(2 * hc->tx_x, min_rate); |
148 | hc->tx_x = max(hc->tx_x, | |
149 | scaled_div(((__u64)hc->tx_s) << 6, hc->tx_rtt)); | |
150 | hc->tx_t_ld = now; | |
ff586298 | 151 | } |
b6ee3d4a | 152 | |
996ccf49 | 153 | if (hc->tx_x != old_x) { |
1761f7d7 GR |
154 | ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, " |
155 | "X_recv=%u\n", (unsigned)(old_x >> 6), | |
996ccf49 GR |
156 | (unsigned)(hc->tx_x >> 6), hc->tx_x_calc, |
157 | (unsigned)(hc->tx_x_recv >> 6)); | |
8699be7d | 158 | |
996ccf49 | 159 | ccid3_update_send_interval(hc); |
8699be7d | 160 | } |
7c657876 ACM |
161 | } |
162 | ||
78ad713d | 163 | /* |
410e27a4 GR |
164 | * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1) |
165 | * @len: DCCP packet payload size in bytes | |
78ad713d | 166 | */ |
996ccf49 | 167 | static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hc, int len) |
78ad713d | 168 | { |
996ccf49 | 169 | const u16 old_s = hc->tx_s; |
410e27a4 | 170 | |
996ccf49 | 171 | hc->tx_s = tfrc_ewma(hc->tx_s, len, 9); |
410e27a4 | 172 | |
996ccf49 GR |
173 | if (hc->tx_s != old_s) |
174 | ccid3_update_send_interval(hc); | |
78ad713d GR |
175 | } |
176 | ||
9f8681db | 177 | /* |
8109b02b | 178 | * Update Window Counter using the algorithm from [RFC 4342, 8.1]. |
825de27d | 179 | * As elsewhere, RTT > 0 is assumed by using dccp_sample_rtt(). |
9f8681db | 180 | */ |
996ccf49 | 181 | static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hc, |
8132da4d | 182 | ktime_t now) |
9f8681db | 183 | { |
996ccf49 GR |
184 | u32 delta = ktime_us_delta(now, hc->tx_t_last_win_count), |
185 | quarter_rtts = (4 * delta) / hc->tx_rtt; | |
9f8681db GR |
186 | |
187 | if (quarter_rtts > 0) { | |
996ccf49 GR |
188 | hc->tx_t_last_win_count = now; |
189 | hc->tx_last_win_count += min(quarter_rtts, 5U); | |
190 | hc->tx_last_win_count &= 0xF; /* mod 16 */ | |
9f8681db GR |
191 | } |
192 | } | |
193 | ||
7c657876 ACM |
194 | static void ccid3_hc_tx_no_feedback_timer(unsigned long data) |
195 | { | |
196 | struct sock *sk = (struct sock *)data; | |
996ccf49 | 197 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
2a1fda6f | 198 | unsigned long t_nfb = USEC_PER_SEC / 5; |
7c657876 ACM |
199 | |
200 | bh_lock_sock(sk); | |
201 | if (sock_owned_by_user(sk)) { | |
202 | /* Try again later. */ | |
203 | /* XXX: set some sensible MIB */ | |
48e03eee | 204 | goto restart_timer; |
7c657876 ACM |
205 | } |
206 | ||
b1383380 | 207 | ccid3_pr_debug("%s(%p, state=%s) - entry\n", dccp_role(sk), sk, |
996ccf49 | 208 | ccid3_tx_state_name(hc->tx_state)); |
a9672411 | 209 | |
80763dfb GR |
210 | /* Ignore and do not restart after leaving the established state */ |
211 | if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN)) | |
212 | goto out; | |
213 | ||
214 | /* Reset feedback state to "no feedback received" */ | |
996ccf49 | 215 | if (hc->tx_state == TFRC_SSTATE_FBACK) |
410e27a4 | 216 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); |
d0995e6a | 217 | |
52515e77 GR |
218 | /* |
219 | * Determine new allowed sending rate X as per draft rfc3448bis-00, 4.4 | |
67b67e36 | 220 | * RTO is 0 if and only if no feedback has been received yet. |
52515e77 | 221 | */ |
67b67e36 | 222 | if (hc->tx_t_rto == 0 || hc->tx_p == 0) { |
52515e77 GR |
223 | |
224 | /* halve send rate directly */ | |
996ccf49 GR |
225 | hc->tx_x = max(hc->tx_x / 2, |
226 | (((__u64)hc->tx_s) << 6) / TFRC_T_MBI); | |
227 | ccid3_update_send_interval(hc); | |
52515e77 | 228 | } else { |
1f2333ae | 229 | /* |
52515e77 | 230 | * Modify the cached value of X_recv |
0c150efb | 231 | * |
52515e77 | 232 | * If (X_calc > 2 * X_recv) |
0c150efb GR |
233 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); |
234 | * Else | |
235 | * X_recv = X_calc / 4; | |
236 | * | |
237 | * Note that X_recv is scaled by 2^6 while X_calc is not | |
1f2333ae | 238 | */ |
996ccf49 | 239 | BUG_ON(hc->tx_p && !hc->tx_x_calc); |
0c150efb | 240 | |
996ccf49 GR |
241 | if (hc->tx_x_calc > (hc->tx_x_recv >> 5)) |
242 | hc->tx_x_recv = | |
243 | max(hc->tx_x_recv / 2, | |
244 | (((__u64)hc->tx_s) << 6) / (2*TFRC_T_MBI)); | |
52515e77 | 245 | else { |
996ccf49 GR |
246 | hc->tx_x_recv = hc->tx_x_calc; |
247 | hc->tx_x_recv <<= 4; | |
7c657876 | 248 | } |
aa97efd9 | 249 | ccid3_hc_tx_update_x(sk, NULL); |
7c657876 | 250 | } |
52515e77 | 251 | ccid3_pr_debug("Reduced X to %llu/64 bytes/sec\n", |
996ccf49 | 252 | (unsigned long long)hc->tx_x); |
52515e77 GR |
253 | |
254 | /* | |
255 | * Set new timeout for the nofeedback timer. | |
256 | * See comments in packet_recv() regarding the value of t_RTO. | |
257 | */ | |
67b67e36 | 258 | if (unlikely(hc->tx_t_rto == 0)) /* no feedback received yet */ |
52515e77 GR |
259 | t_nfb = TFRC_INITIAL_TIMEOUT; |
260 | else | |
996ccf49 | 261 | t_nfb = max(hc->tx_t_rto, 2 * hc->tx_t_ipi); |
7c657876 | 262 | |
48e03eee | 263 | restart_timer: |
996ccf49 | 264 | sk_reset_timer(sk, &hc->tx_no_feedback_timer, |
c9eaf173 | 265 | jiffies + usecs_to_jiffies(t_nfb)); |
7c657876 ACM |
266 | out: |
267 | bh_unlock_sock(sk); | |
268 | sock_put(sk); | |
269 | } | |
270 | ||
fe84f414 GR |
271 | /** |
272 | * ccid3_hc_tx_send_packet - Delay-based dequeueing of TX packets | |
273 | * @skb: next packet candidate to send on @sk | |
274 | * This function uses the convention of ccid_packet_dequeue_eval() and | |
275 | * returns a millisecond-delay value between 0 and t_mbi = 64000 msec. | |
7da7f456 | 276 | */ |
6b57c93d | 277 | static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) |
7c657876 ACM |
278 | { |
279 | struct dccp_sock *dp = dccp_sk(sk); | |
996ccf49 | 280 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
8132da4d GR |
281 | ktime_t now = ktime_get_real(); |
282 | s64 delay; | |
7c657876 | 283 | |
7c657876 | 284 | /* |
da335baf GR |
285 | * This function is called only for Data and DataAck packets. Sending |
286 | * zero-sized Data(Ack)s is theoretically possible, but for congestion | |
287 | * control this case is pathological - ignore it. | |
7c657876 | 288 | */ |
6b57c93d | 289 | if (unlikely(skb->len == 0)) |
da335baf | 290 | return -EBADMSG; |
7c657876 | 291 | |
80763dfb | 292 | if (hc->tx_state == TFRC_SSTATE_NO_SENT) { |
996ccf49 GR |
293 | sk_reset_timer(sk, &hc->tx_no_feedback_timer, (jiffies + |
294 | usecs_to_jiffies(TFRC_INITIAL_TIMEOUT))); | |
295 | hc->tx_last_win_count = 0; | |
296 | hc->tx_t_last_win_count = now; | |
90feeb95 GR |
297 | |
298 | /* Set t_0 for initial packet */ | |
996ccf49 | 299 | hc->tx_t_nom = now; |
410e27a4 | 300 | |
996ccf49 | 301 | hc->tx_s = skb->len; |
30833ffe | 302 | |
30833ffe GR |
303 | /* |
304 | * Use initial RTT sample when available: recommended by erratum | |
305 | * to RFC 4342. This implements the initialisation procedure of | |
306 | * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6. | |
307 | */ | |
308 | if (dp->dccps_syn_rtt) { | |
309 | ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt); | |
996ccf49 GR |
310 | hc->tx_rtt = dp->dccps_syn_rtt; |
311 | hc->tx_x = rfc3390_initial_rate(sk); | |
312 | hc->tx_t_ld = now; | |
30833ffe | 313 | } else { |
3294f202 GR |
314 | /* |
315 | * Sender does not have RTT sample: | |
316 | * - set fallback RTT (RFC 4340, 3.4) since a RTT value | |
317 | * is needed in several parts (e.g. window counter); | |
318 | * - set sending rate X_pps = 1pps as per RFC 3448, 4.2. | |
319 | */ | |
996ccf49 GR |
320 | hc->tx_rtt = DCCP_FALLBACK_RTT; |
321 | hc->tx_x = hc->tx_s; | |
322 | hc->tx_x <<= 6; | |
30833ffe | 323 | } |
996ccf49 | 324 | ccid3_update_send_interval(hc); |
30833ffe | 325 | |
410e27a4 | 326 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); |
80763dfb GR |
327 | |
328 | } else { | |
996ccf49 | 329 | delay = ktime_us_delta(hc->tx_t_nom, now); |
8699be7d | 330 | ccid3_pr_debug("delay=%ld\n", (long)delay); |
91cf5a17 | 331 | /* |
20cbd3e1 | 332 | * Scheduling of packet transmissions (RFC 5348, 8.3) |
91cf5a17 GR |
333 | * |
334 | * if (t_now > t_nom - delta) | |
335 | * // send the packet now | |
336 | * else | |
337 | * // send the packet in (t_nom - t_now) milliseconds. | |
338 | */ | |
20cbd3e1 GR |
339 | if (delay >= TFRC_T_DELTA) |
340 | return (u32)delay / USEC_PER_MSEC; | |
9f8681db | 341 | |
996ccf49 | 342 | ccid3_hc_tx_update_win_count(hc, now); |
7c657876 ACM |
343 | } |
344 | ||
7da7f456 GR |
345 | /* prepare to send now (add options etc.) */ |
346 | dp->dccps_hc_tx_insert_options = 1; | |
996ccf49 | 347 | DCCP_SKB_CB(skb)->dccpd_ccval = hc->tx_last_win_count; |
e312d100 GR |
348 | |
349 | /* set the nominal send time for the next following packet */ | |
996ccf49 | 350 | hc->tx_t_nom = ktime_add_us(hc->tx_t_nom, hc->tx_t_ipi); |
fe84f414 | 351 | return CCID_PACKET_SEND_AT_ONCE; |
7c657876 ACM |
352 | } |
353 | ||
baf9e782 | 354 | static void ccid3_hc_tx_packet_sent(struct sock *sk, unsigned int len) |
7c657876 | 355 | { |
996ccf49 | 356 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
7c657876 | 357 | |
996ccf49 | 358 | ccid3_hc_tx_update_s(hc, len); |
7c657876 | 359 | |
996ccf49 | 360 | if (tfrc_tx_hist_add(&hc->tx_hist, dccp_sk(sk)->dccps_gss)) |
c5a1ae9a | 361 | DCCP_CRIT("packet history - out of memory!"); |
7c657876 ACM |
362 | } |
363 | ||
364 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) | |
365 | { | |
996ccf49 | 366 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
d2c72630 | 367 | struct tfrc_tx_hist_entry *acked; |
0740d49c | 368 | ktime_t now; |
2a1fda6f | 369 | unsigned long t_nfb; |
536bb20b | 370 | u32 r_sample; |
1f2333ae | 371 | |
7c657876 ACM |
372 | /* we are only interested in ACKs */ |
373 | if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || | |
374 | DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) | |
375 | return; | |
d2c72630 GR |
376 | /* |
377 | * Locate the acknowledged packet in the TX history. | |
378 | * | |
379 | * Returning "entry not found" here can for instance happen when | |
380 | * - the host has not sent out anything (e.g. a passive server), | |
381 | * - the Ack is outdated (packet with higher Ack number was received), | |
382 | * - it is a bogus Ack (for a packet not sent on this connection). | |
383 | */ | |
384 | acked = tfrc_tx_hist_find_entry(hc->tx_hist, dccp_hdr_ack_seq(skb)); | |
385 | if (acked == NULL) | |
5bd370a6 | 386 | return; |
d2c72630 GR |
387 | /* For the sake of RTT sampling, ignore/remove all older entries */ |
388 | tfrc_tx_hist_purge(&acked->next); | |
389 | ||
390 | /* Update the moving average for the RTT estimate (RFC 3448, 4.3) */ | |
391 | now = ktime_get_real(); | |
392 | r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, acked->stamp)); | |
393 | hc->tx_rtt = tfrc_ewma(hc->tx_rtt, r_sample, 9); | |
63b3a73b | 394 | |
d8d1252f GR |
395 | /* |
396 | * Update allowed sending rate X as per draft rfc3448bis-00, 4.2/3 | |
397 | */ | |
996ccf49 | 398 | if (hc->tx_state == TFRC_SSTATE_NO_FBACK) { |
410e27a4 | 399 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); |
5c3fbb6a | 400 | |
996ccf49 | 401 | if (hc->tx_t_rto == 0) { |
d8d1252f GR |
402 | /* |
403 | * Initial feedback packet: Larger Initial Windows (4.2) | |
404 | */ | |
996ccf49 GR |
405 | hc->tx_x = rfc3390_initial_rate(sk); |
406 | hc->tx_t_ld = now; | |
a79ef76f | 407 | |
996ccf49 | 408 | ccid3_update_send_interval(hc); |
7c657876 | 409 | |
d8d1252f | 410 | goto done_computing_x; |
996ccf49 | 411 | } else if (hc->tx_p == 0) { |
d8d1252f GR |
412 | /* |
413 | * First feedback after nofeedback timer expiry (4.3) | |
414 | */ | |
415 | goto done_computing_x; | |
416 | } | |
417 | } | |
7c657876 | 418 | |
d8d1252f | 419 | /* Update sending rate (step 4 of [RFC 3448, 4.3]) */ |
996ccf49 GR |
420 | if (hc->tx_p > 0) |
421 | hc->tx_x_calc = tfrc_calc_x(hc->tx_s, hc->tx_rtt, hc->tx_p); | |
d8d1252f | 422 | ccid3_hc_tx_update_x(sk, &now); |
7c657876 | 423 | |
d8d1252f GR |
424 | done_computing_x: |
425 | ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, " | |
5bd370a6 | 426 | "p=%u, X_calc=%u, X_recv=%u, X=%u\n", |
996ccf49 GR |
427 | dccp_role(sk), sk, hc->tx_rtt, r_sample, |
428 | hc->tx_s, hc->tx_p, hc->tx_x_calc, | |
429 | (unsigned)(hc->tx_x_recv >> 6), | |
430 | (unsigned)(hc->tx_x >> 6)); | |
7c657876 | 431 | |
5bd370a6 | 432 | /* unschedule no feedback timer */ |
996ccf49 | 433 | sk_stop_timer(sk, &hc->tx_no_feedback_timer); |
7c657876 | 434 | |
5bd370a6 GR |
435 | /* |
436 | * As we have calculated new ipi, delta, t_nom it is possible | |
437 | * that we now can send a packet, so wake up dccp_wait_for_ccid | |
438 | */ | |
439 | sk->sk_write_space(sk); | |
8c60f3fa | 440 | |
5bd370a6 | 441 | /* |
89858ad1 GR |
442 | * Update timeout interval for the nofeedback timer. In order to control |
443 | * rate halving on networks with very low RTTs (<= 1 ms), use per-route | |
444 | * tunable RTAX_RTO_MIN value as the lower bound. | |
5bd370a6 | 445 | */ |
89858ad1 GR |
446 | hc->tx_t_rto = max_t(u32, 4 * hc->tx_rtt, |
447 | USEC_PER_SEC/HZ * tcp_rto_min(sk)); | |
5bd370a6 GR |
448 | /* |
449 | * Schedule no feedback timer to expire in | |
450 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) | |
451 | */ | |
996ccf49 | 452 | t_nfb = max(hc->tx_t_rto, 2 * hc->tx_t_ipi); |
7c657876 | 453 | |
5bd370a6 GR |
454 | ccid3_pr_debug("%s(%p), Scheduled no feedback timer to " |
455 | "expire in %lu jiffies (%luus)\n", | |
388d5e99 | 456 | dccp_role(sk), sk, usecs_to_jiffies(t_nfb), t_nfb); |
a9672411 | 457 | |
996ccf49 | 458 | sk_reset_timer(sk, &hc->tx_no_feedback_timer, |
5bd370a6 | 459 | jiffies + usecs_to_jiffies(t_nfb)); |
7c657876 ACM |
460 | } |
461 | ||
4874c131 GR |
462 | static int ccid3_hc_tx_parse_options(struct sock *sk, u8 packet_type, |
463 | u8 option, u8 *optval, u8 optlen) | |
7c657876 | 464 | { |
996ccf49 | 465 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
76fd1e87 | 466 | __be32 opt_val; |
7c657876 | 467 | |
410e27a4 | 468 | switch (option) { |
37efb03f | 469 | case TFRC_OPT_RECEIVE_RATE: |
410e27a4 | 470 | case TFRC_OPT_LOSS_EVENT_RATE: |
4874c131 GR |
471 | /* Must be ignored on Data packets, cf. RFC 4342 8.3 and 8.5 */ |
472 | if (packet_type == DCCP_PKT_DATA) | |
473 | break; | |
474 | if (unlikely(optlen != 4)) { | |
37efb03f | 475 | DCCP_WARN("%s(%p), invalid len %d for %u\n", |
4874c131 | 476 | dccp_role(sk), sk, optlen, option); |
37efb03f | 477 | return -EINVAL; |
7c657876 | 478 | } |
4874c131 | 479 | opt_val = ntohl(get_unaligned((__be32 *)optval)); |
37efb03f GR |
480 | |
481 | if (option == TFRC_OPT_RECEIVE_RATE) { | |
536bb20b GR |
482 | /* Receive Rate is kept in units of 64 bytes/second */ |
483 | hc->tx_x_recv = opt_val; | |
484 | hc->tx_x_recv <<= 6; | |
485 | ||
410e27a4 | 486 | ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n", |
37efb03f GR |
487 | dccp_role(sk), sk, opt_val); |
488 | } else { | |
536bb20b GR |
489 | /* Update the fixpoint Loss Event Rate fraction */ |
490 | hc->tx_p = tfrc_invert_loss_event_rate(opt_val); | |
491 | ||
37efb03f GR |
492 | ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n", |
493 | dccp_role(sk), sk, opt_val); | |
410e27a4 | 494 | } |
7c657876 | 495 | } |
37efb03f | 496 | return 0; |
7c657876 ACM |
497 | } |
498 | ||
91f0ebf7 | 499 | static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk) |
7c657876 | 500 | { |
996ccf49 | 501 | struct ccid3_hc_tx_sock *hc = ccid_priv(ccid); |
7c657876 | 502 | |
996ccf49 GR |
503 | hc->tx_state = TFRC_SSTATE_NO_SENT; |
504 | hc->tx_hist = NULL; | |
505 | setup_timer(&hc->tx_no_feedback_timer, | |
410e27a4 | 506 | ccid3_hc_tx_no_feedback_timer, (unsigned long)sk); |
7c657876 ACM |
507 | return 0; |
508 | } | |
509 | ||
510 | static void ccid3_hc_tx_exit(struct sock *sk) | |
511 | { | |
996ccf49 | 512 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
7c657876 | 513 | |
996ccf49 | 514 | sk_stop_timer(sk, &hc->tx_no_feedback_timer); |
996ccf49 | 515 | tfrc_tx_hist_purge(&hc->tx_hist); |
7c657876 ACM |
516 | } |
517 | ||
9bf17475 GR |
518 | static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) |
519 | { | |
51c22bb5 GR |
520 | info->tcpi_rto = ccid3_hc_tx_sk(sk)->tx_t_rto; |
521 | info->tcpi_rtt = ccid3_hc_tx_sk(sk)->tx_rtt; | |
9bf17475 GR |
522 | } |
523 | ||
524 | static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, | |
525 | u32 __user *optval, int __user *optlen) | |
526 | { | |
51c22bb5 | 527 | const struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
67b67e36 | 528 | struct tfrc_tx_info tfrc; |
9bf17475 GR |
529 | const void *val; |
530 | ||
9bf17475 GR |
531 | switch (optname) { |
532 | case DCCP_SOCKOPT_CCID_TX_INFO: | |
67b67e36 | 533 | if (len < sizeof(tfrc)) |
9bf17475 | 534 | return -EINVAL; |
67b67e36 GR |
535 | tfrc.tfrctx_x = hc->tx_x; |
536 | tfrc.tfrctx_x_recv = hc->tx_x_recv; | |
537 | tfrc.tfrctx_x_calc = hc->tx_x_calc; | |
538 | tfrc.tfrctx_rtt = hc->tx_rtt; | |
539 | tfrc.tfrctx_p = hc->tx_p; | |
540 | tfrc.tfrctx_rto = hc->tx_t_rto; | |
541 | tfrc.tfrctx_ipi = hc->tx_t_ipi; | |
542 | len = sizeof(tfrc); | |
543 | val = &tfrc; | |
9bf17475 GR |
544 | break; |
545 | default: | |
546 | return -ENOPROTOOPT; | |
547 | } | |
548 | ||
549 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) | |
550 | return -EFAULT; | |
551 | ||
552 | return 0; | |
553 | } | |
554 | ||
7c657876 | 555 | /* |
9bf17475 | 556 | * Receiver Half-Connection Routines |
7c657876 | 557 | */ |
410e27a4 GR |
558 | |
559 | /* CCID3 feedback types */ | |
560 | enum ccid3_fback_type { | |
561 | CCID3_FBACK_NONE = 0, | |
562 | CCID3_FBACK_INITIAL, | |
563 | CCID3_FBACK_PERIODIC, | |
564 | CCID3_FBACK_PARAM_CHANGE | |
565 | }; | |
566 | ||
567 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG | |
568 | static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) | |
569 | { | |
36cbd3dc | 570 | static const char *const ccid3_rx_state_names[] = { |
410e27a4 GR |
571 | [TFRC_RSTATE_NO_DATA] = "NO_DATA", |
572 | [TFRC_RSTATE_DATA] = "DATA", | |
410e27a4 GR |
573 | }; |
574 | ||
575 | return ccid3_rx_state_names[state]; | |
576 | } | |
577 | #endif | |
578 | ||
579 | static void ccid3_hc_rx_set_state(struct sock *sk, | |
580 | enum ccid3_hc_rx_states state) | |
581 | { | |
996ccf49 GR |
582 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
583 | enum ccid3_hc_rx_states oldstate = hc->rx_state; | |
410e27a4 GR |
584 | |
585 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | |
586 | dccp_role(sk), sk, ccid3_rx_state_name(oldstate), | |
587 | ccid3_rx_state_name(state)); | |
588 | WARN_ON(state == oldstate); | |
996ccf49 | 589 | hc->rx_state = state; |
410e27a4 GR |
590 | } |
591 | ||
b84a2189 ACM |
592 | static void ccid3_hc_rx_send_feedback(struct sock *sk, |
593 | const struct sk_buff *skb, | |
594 | enum ccid3_fback_type fbtype) | |
7c657876 | 595 | { |
996ccf49 | 596 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
410e27a4 | 597 | struct dccp_sock *dp = dccp_sk(sk); |
80763dfb | 598 | ktime_t now = ktime_get_real(); |
410e27a4 GR |
599 | s64 delta = 0; |
600 | ||
b84a2189 ACM |
601 | switch (fbtype) { |
602 | case CCID3_FBACK_INITIAL: | |
996ccf49 GR |
603 | hc->rx_x_recv = 0; |
604 | hc->rx_pinv = ~0U; /* see RFC 4342, 8.5 */ | |
7c657876 | 605 | break; |
b84a2189 ACM |
606 | case CCID3_FBACK_PARAM_CHANGE: |
607 | /* | |
608 | * When parameters change (new loss or p > p_prev), we do not | |
609 | * have a reliable estimate for R_m of [RFC 3448, 6.2] and so | |
410e27a4 GR |
610 | * need to reuse the previous value of X_recv. However, when |
611 | * X_recv was 0 (due to early loss), this would kill X down to | |
612 | * s/t_mbi (i.e. one packet in 64 seconds). | |
613 | * To avoid such drastic reduction, we approximate X_recv as | |
614 | * the number of bytes since last feedback. | |
615 | * This is a safe fallback, since X is bounded above by X_calc. | |
b84a2189 | 616 | */ |
996ccf49 | 617 | if (hc->rx_x_recv > 0) |
410e27a4 GR |
618 | break; |
619 | /* fall through */ | |
b84a2189 | 620 | case CCID3_FBACK_PERIODIC: |
996ccf49 | 621 | delta = ktime_us_delta(now, hc->rx_tstamp_last_feedback); |
410e27a4 GR |
622 | if (delta <= 0) |
623 | DCCP_BUG("delta (%ld) <= 0", (long)delta); | |
624 | else | |
996ccf49 | 625 | hc->rx_x_recv = scaled_div32(hc->rx_bytes_recv, delta); |
7c657876 | 626 | break; |
b84a2189 | 627 | default: |
7c657876 ACM |
628 | return; |
629 | } | |
630 | ||
410e27a4 | 631 | ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", (long)delta, |
996ccf49 | 632 | hc->rx_x_recv, hc->rx_pinv); |
7c657876 | 633 | |
996ccf49 GR |
634 | hc->rx_tstamp_last_feedback = now; |
635 | hc->rx_last_counter = dccp_hdr(skb)->dccph_ccval; | |
636 | hc->rx_bytes_recv = 0; | |
68c89ee5 | 637 | |
410e27a4 GR |
638 | dp->dccps_hc_rx_insert_options = 1; |
639 | dccp_send_ack(sk); | |
7c657876 ACM |
640 | } |
641 | ||
2d0817d1 | 642 | static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) |
7c657876 | 643 | { |
51c22bb5 | 644 | const struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
60fe62e7 | 645 | __be32 x_recv, pinv; |
7c657876 | 646 | |
59d203f9 | 647 | if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) |
2d0817d1 | 648 | return 0; |
7c657876 | 649 | |
4fded33b | 650 | if (dccp_packet_without_ack(skb)) |
2d0817d1 ACM |
651 | return 0; |
652 | ||
996ccf49 GR |
653 | x_recv = htonl(hc->rx_x_recv); |
654 | pinv = htonl(hc->rx_pinv); | |
2d0817d1 | 655 | |
a7d13fbf | 656 | if (dccp_insert_option(skb, TFRC_OPT_LOSS_EVENT_RATE, |
8109b02b | 657 | &pinv, sizeof(pinv)) || |
a7d13fbf | 658 | dccp_insert_option(skb, TFRC_OPT_RECEIVE_RATE, |
8109b02b | 659 | &x_recv, sizeof(x_recv))) |
2d0817d1 ACM |
660 | return -1; |
661 | ||
662 | return 0; | |
7c657876 ACM |
663 | } |
664 | ||
aa1b1ff0 GR |
665 | /** |
666 | * ccid3_first_li - Implements [RFC 5348, 6.3.1] | |
954c2db8 GR |
667 | * |
668 | * Determine the length of the first loss interval via inverse lookup. | |
669 | * Assume that X_recv can be computed by the throughput equation | |
670 | * s | |
671 | * X_recv = -------- | |
672 | * R * fval | |
673 | * Find some p such that f(p) = fval; return 1/p (scaled). | |
674 | */ | |
675 | static u32 ccid3_first_li(struct sock *sk) | |
676 | { | |
996ccf49 | 677 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
410e27a4 | 678 | u32 x_recv, p, delta; |
954c2db8 GR |
679 | u64 fval; |
680 | ||
996ccf49 | 681 | if (hc->rx_rtt == 0) { |
410e27a4 | 682 | DCCP_WARN("No RTT estimate available, using fallback RTT\n"); |
996ccf49 | 683 | hc->rx_rtt = DCCP_FALLBACK_RTT; |
410e27a4 | 684 | } |
d20ed95f | 685 | |
996ccf49 GR |
686 | delta = ktime_to_us(net_timedelta(hc->rx_tstamp_last_feedback)); |
687 | x_recv = scaled_div32(hc->rx_bytes_recv, delta); | |
410e27a4 GR |
688 | if (x_recv == 0) { /* would also trigger divide-by-zero */ |
689 | DCCP_WARN("X_recv==0\n"); | |
67b67e36 | 690 | if (hc->rx_x_recv == 0) { |
410e27a4 GR |
691 | DCCP_BUG("stored value of X_recv is zero"); |
692 | return ~0U; | |
693 | } | |
67b67e36 | 694 | x_recv = hc->rx_x_recv; |
410e27a4 | 695 | } |
954c2db8 | 696 | |
996ccf49 | 697 | fval = scaled_div(hc->rx_s, hc->rx_rtt); |
410e27a4 | 698 | fval = scaled_div32(fval, x_recv); |
954c2db8 GR |
699 | p = tfrc_calc_x_reverse_lookup(fval); |
700 | ||
701 | ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied " | |
702 | "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); | |
703 | ||
410e27a4 | 704 | return p == 0 ? ~0U : scaled_div(1, p); |
954c2db8 GR |
705 | } |
706 | ||
b84a2189 | 707 | static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) |
7c657876 | 708 | { |
996ccf49 | 709 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
410e27a4 | 710 | enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE; |
5b5d0e70 | 711 | const u64 ndp = dccp_sk(sk)->dccps_options_received.dccpor_ndp; |
b84a2189 ACM |
712 | const bool is_data_packet = dccp_data_packet(skb); |
713 | ||
996ccf49 | 714 | if (unlikely(hc->rx_state == TFRC_RSTATE_NO_DATA)) { |
410e27a4 GR |
715 | if (is_data_packet) { |
716 | const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; | |
717 | do_feedback = CCID3_FBACK_INITIAL; | |
718 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); | |
996ccf49 | 719 | hc->rx_s = payload; |
410e27a4 | 720 | /* |
388d5e99 | 721 | * Not necessary to update rx_bytes_recv here, |
410e27a4 GR |
722 | * since X_recv = 0 for the first feedback packet (cf. |
723 | * RFC 3448, 6.3) -- gerrit | |
724 | */ | |
725 | } | |
726 | goto update_records; | |
727 | } | |
728 | ||
996ccf49 | 729 | if (tfrc_rx_hist_duplicate(&hc->rx_hist, skb)) |
410e27a4 GR |
730 | return; /* done receiving */ |
731 | ||
732 | if (is_data_packet) { | |
733 | const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; | |
734 | /* | |
735 | * Update moving-average of s and the sum of received payload bytes | |
736 | */ | |
996ccf49 GR |
737 | hc->rx_s = tfrc_ewma(hc->rx_s, payload, 9); |
738 | hc->rx_bytes_recv += payload; | |
410e27a4 GR |
739 | } |
740 | ||
d20ed95f GR |
741 | /* |
742 | * Perform loss detection and handle pending losses | |
743 | */ | |
996ccf49 | 744 | if (tfrc_rx_handle_loss(&hc->rx_hist, &hc->rx_li_hist, |
410e27a4 GR |
745 | skb, ndp, ccid3_first_li, sk)) { |
746 | do_feedback = CCID3_FBACK_PARAM_CHANGE; | |
747 | goto done_receiving; | |
748 | } | |
749 | ||
996ccf49 | 750 | if (tfrc_rx_hist_loss_pending(&hc->rx_hist)) |
410e27a4 GR |
751 | return; /* done receiving */ |
752 | ||
88e97a93 | 753 | /* |
410e27a4 | 754 | * Handle data packets: RTT sampling and monitoring p |
88e97a93 | 755 | */ |
410e27a4 GR |
756 | if (unlikely(!is_data_packet)) |
757 | goto update_records; | |
758 | ||
996ccf49 GR |
759 | if (!tfrc_lh_is_initialised(&hc->rx_li_hist)) { |
760 | const u32 sample = tfrc_rx_hist_sample_rtt(&hc->rx_hist, skb); | |
410e27a4 GR |
761 | /* |
762 | * Empty loss history: no loss so far, hence p stays 0. | |
763 | * Sample RTT values, since an RTT estimate is required for the | |
764 | * computation of p when the first loss occurs; RFC 3448, 6.3.1. | |
765 | */ | |
766 | if (sample != 0) | |
996ccf49 | 767 | hc->rx_rtt = tfrc_ewma(hc->rx_rtt, sample, 9); |
410e27a4 | 768 | |
996ccf49 | 769 | } else if (tfrc_lh_update_i_mean(&hc->rx_li_hist, skb)) { |
410e27a4 GR |
770 | /* |
771 | * Step (3) of [RFC 3448, 6.1]: Recompute I_mean and, if I_mean | |
772 | * has decreased (resp. p has increased), send feedback now. | |
773 | */ | |
774 | do_feedback = CCID3_FBACK_PARAM_CHANGE; | |
775 | } | |
776 | ||
b84a2189 ACM |
777 | /* |
778 | * Check if the periodic once-per-RTT feedback is due; RFC 4342, 10.3 | |
779 | */ | |
996ccf49 | 780 | if (SUB16(dccp_hdr(skb)->dccph_ccval, hc->rx_last_counter) > 3) |
410e27a4 GR |
781 | do_feedback = CCID3_FBACK_PERIODIC; |
782 | ||
783 | update_records: | |
996ccf49 | 784 | tfrc_rx_hist_add_packet(&hc->rx_hist, skb, ndp); |
410e27a4 GR |
785 | |
786 | done_receiving: | |
787 | if (do_feedback) | |
788 | ccid3_hc_rx_send_feedback(sk, skb, do_feedback); | |
7c657876 ACM |
789 | } |
790 | ||
91f0ebf7 | 791 | static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk) |
7c657876 | 792 | { |
996ccf49 | 793 | struct ccid3_hc_rx_sock *hc = ccid_priv(ccid); |
7c657876 | 794 | |
996ccf49 GR |
795 | hc->rx_state = TFRC_RSTATE_NO_DATA; |
796 | tfrc_lh_init(&hc->rx_li_hist); | |
797 | return tfrc_rx_hist_alloc(&hc->rx_hist); | |
7c657876 ACM |
798 | } |
799 | ||
800 | static void ccid3_hc_rx_exit(struct sock *sk) | |
801 | { | |
996ccf49 | 802 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
7c657876 | 803 | |
996ccf49 GR |
804 | tfrc_rx_hist_purge(&hc->rx_hist); |
805 | tfrc_lh_cleanup(&hc->rx_li_hist); | |
7c657876 ACM |
806 | } |
807 | ||
2babe1f6 ACM |
808 | static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) |
809 | { | |
51c22bb5 | 810 | info->tcpi_ca_state = ccid3_hc_rx_sk(sk)->rx_state; |
8109b02b | 811 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; |
51c22bb5 | 812 | info->tcpi_rcv_rtt = ccid3_hc_rx_sk(sk)->rx_rtt; |
2babe1f6 ACM |
813 | } |
814 | ||
88f964db ACM |
815 | static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, |
816 | u32 __user *optval, int __user *optlen) | |
817 | { | |
51c22bb5 | 818 | const struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
8e138e79 | 819 | struct tfrc_rx_info rx_info; |
88f964db | 820 | const void *val; |
c9eaf173 | 821 | |
88f964db ACM |
822 | switch (optname) { |
823 | case DCCP_SOCKOPT_CCID_RX_INFO: | |
8e138e79 | 824 | if (len < sizeof(rx_info)) |
88f964db | 825 | return -EINVAL; |
996ccf49 GR |
826 | rx_info.tfrcrx_x_recv = hc->rx_x_recv; |
827 | rx_info.tfrcrx_rtt = hc->rx_rtt; | |
792e6d33 | 828 | rx_info.tfrcrx_p = tfrc_invert_loss_event_rate(hc->rx_pinv); |
8e138e79 GR |
829 | len = sizeof(rx_info); |
830 | val = &rx_info; | |
88f964db ACM |
831 | break; |
832 | default: | |
833 | return -ENOPROTOOPT; | |
834 | } | |
835 | ||
836 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) | |
837 | return -EFAULT; | |
838 | ||
839 | return 0; | |
840 | } | |
841 | ||
ddebc973 | 842 | struct ccid_operations ccid3_ops = { |
3dd9a7c3 | 843 | .ccid_id = DCCPC_CCID3, |
84a97b0a | 844 | .ccid_name = "TCP-Friendly Rate Control", |
91f0ebf7 | 845 | .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock), |
7c657876 ACM |
846 | .ccid_hc_tx_init = ccid3_hc_tx_init, |
847 | .ccid_hc_tx_exit = ccid3_hc_tx_exit, | |
848 | .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, | |
849 | .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, | |
850 | .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, | |
7c657876 | 851 | .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, |
91f0ebf7 | 852 | .ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock), |
7c657876 ACM |
853 | .ccid_hc_rx_init = ccid3_hc_rx_init, |
854 | .ccid_hc_rx_exit = ccid3_hc_rx_exit, | |
855 | .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, | |
856 | .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, | |
2babe1f6 ACM |
857 | .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, |
858 | .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, | |
88f964db ACM |
859 | .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt, |
860 | .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt, | |
7c657876 | 861 | }; |
8109b02b | 862 | |
56724aa4 | 863 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
43264991 | 864 | module_param(ccid3_debug, bool, 0644); |
ddebc973 | 865 | MODULE_PARM_DESC(ccid3_debug, "Enable CCID-3 debug messages"); |
56724aa4 | 866 | #endif |