diff options
Diffstat (limited to 'net/dccp/ccids/ccid3.c')
| -rw-r--r-- | net/dccp/ccids/ccid3.c | 1221 |
1 files changed, 1221 insertions, 0 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c new file mode 100644 index 000000000000..7bf3b3a91e97 --- /dev/null +++ b/net/dccp/ccids/ccid3.c | |||
| @@ -0,0 +1,1221 @@ | |||
| 1 | /* | ||
| 2 | * net/dccp/ccids/ccid3.c | ||
| 3 | * | ||
| 4 | * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. | ||
| 5 | * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> | ||
| 6 | * | ||
| 7 | * An implementation of the DCCP protocol | ||
| 8 | * | ||
| 9 | * This code has been developed by the University of Waikato WAND | ||
| 10 | * research group. For further information please see http://www.wand.net.nz/ | ||
| 11 | * | ||
| 12 | * This code also uses code from Lulea University, rereleased as GPL by its | ||
| 13 | * authors: | ||
| 14 | * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon | ||
| 15 | * | ||
| 16 | * Changes to meet Linux coding standards, to make it meet latest ccid3 draft | ||
| 17 | * and to make it work as a loadable module in the DCCP stack written by | ||
| 18 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br>. | ||
| 19 | * | ||
| 20 | * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> | ||
| 21 | * | ||
| 22 | * This program is free software; you can redistribute it and/or modify | ||
| 23 | * it under the terms of the GNU General Public License as published by | ||
| 24 | * the Free Software Foundation; either version 2 of the License, or | ||
| 25 | * (at your option) any later version. | ||
| 26 | * | ||
| 27 | * This program is distributed in the hope that it will be useful, | ||
| 28 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 29 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
| 30 | * GNU General Public License for more details. | ||
| 31 | * | ||
| 32 | * You should have received a copy of the GNU General Public License | ||
| 33 | * along with this program; if not, write to the Free Software | ||
| 34 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
| 35 | */ | ||
| 36 | |||
| 37 | #include <linux/config.h> | ||
| 38 | #include "../ccid.h" | ||
| 39 | #include "../dccp.h" | ||
| 40 | #include "lib/packet_history.h" | ||
| 41 | #include "lib/loss_interval.h" | ||
| 42 | #include "lib/tfrc.h" | ||
| 43 | #include "ccid3.h" | ||
| 44 | |||
| 45 | /* | ||
| 46 | * Reason for maths with 10 here is to avoid 32 bit overflow when a is big. | ||
| 47 | */ | ||
| 48 | static inline u32 usecs_div(const u32 a, const u32 b) | ||
| 49 | { | ||
| 50 | const u32 tmp = a * (USEC_PER_SEC / 10); | ||
| 51 | return b > 20 ? tmp / (b / 10) : tmp; | ||
| 52 | } | ||
| 53 | |||
| 54 | static int ccid3_debug; | ||
| 55 | |||
| 56 | #ifdef CCID3_DEBUG | ||
| 57 | #define ccid3_pr_debug(format, a...) \ | ||
| 58 | do { if (ccid3_debug) \ | ||
| 59 | printk(KERN_DEBUG "%s: " format, __FUNCTION__, ##a); \ | ||
| 60 | } while (0) | ||
| 61 | #else | ||
| 62 | #define ccid3_pr_debug(format, a...) | ||
| 63 | #endif | ||
| 64 | |||
| 65 | static struct dccp_tx_hist *ccid3_tx_hist; | ||
| 66 | static struct dccp_rx_hist *ccid3_rx_hist; | ||
| 67 | static struct dccp_li_hist *ccid3_li_hist; | ||
| 68 | |||
| 69 | static int ccid3_init(struct sock *sk) | ||
| 70 | { | ||
| 71 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | ||
| 72 | return 0; | ||
| 73 | } | ||
| 74 | |||
| 75 | static void ccid3_exit(struct sock *sk) | ||
| 76 | { | ||
| 77 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | ||
| 78 | } | ||
| 79 | |||
| 80 | /* TFRC sender states */ | ||
| 81 | enum ccid3_hc_tx_states { | ||
| 82 | TFRC_SSTATE_NO_SENT = 1, | ||
| 83 | TFRC_SSTATE_NO_FBACK, | ||
| 84 | TFRC_SSTATE_FBACK, | ||
| 85 | TFRC_SSTATE_TERM, | ||
| 86 | }; | ||
| 87 | |||
| 88 | #ifdef CCID3_DEBUG | ||
| 89 | static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) | ||
| 90 | { | ||
| 91 | static char *ccid3_state_names[] = { | ||
| 92 | [TFRC_SSTATE_NO_SENT] = "NO_SENT", | ||
| 93 | [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", | ||
| 94 | [TFRC_SSTATE_FBACK] = "FBACK", | ||
| 95 | [TFRC_SSTATE_TERM] = "TERM", | ||
| 96 | }; | ||
| 97 | |||
| 98 | return ccid3_state_names[state]; | ||
| 99 | } | ||
| 100 | #endif | ||
| 101 | |||
| 102 | static inline void ccid3_hc_tx_set_state(struct sock *sk, | ||
| 103 | enum ccid3_hc_tx_states state) | ||
| 104 | { | ||
| 105 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 106 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 107 | enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state; | ||
| 108 | |||
| 109 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | ||
| 110 | dccp_role(sk), sk, ccid3_tx_state_name(oldstate), | ||
| 111 | ccid3_tx_state_name(state)); | ||
| 112 | WARN_ON(state == oldstate); | ||
| 113 | hctx->ccid3hctx_state = state; | ||
| 114 | } | ||
| 115 | |||
| 116 | /* Calculate new t_ipi (inter packet interval) by t_ipi = s / X_inst */ | ||
| 117 | static inline void ccid3_calc_new_t_ipi(struct ccid3_hc_tx_sock *hctx) | ||
| 118 | { | ||
| 119 | /* | ||
| 120 | * If no feedback spec says t_ipi is 1 second (set elsewhere and then | ||
| 121 | * doubles after every no feedback timer (separate function) | ||
| 122 | */ | ||
| 123 | if (hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK) | ||
| 124 | hctx->ccid3hctx_t_ipi = usecs_div(hctx->ccid3hctx_s, | ||
| 125 | hctx->ccid3hctx_x); | ||
| 126 | } | ||
| 127 | |||
| 128 | /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ | ||
| 129 | static inline void ccid3_calc_new_delta(struct ccid3_hc_tx_sock *hctx) | ||
| 130 | { | ||
| 131 | hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2, | ||
| 132 | TFRC_OPSYS_HALF_TIME_GRAN); | ||
| 133 | } | ||
| 134 | |||
| 135 | /* | ||
| 136 | * Update X by | ||
| 137 | * If (p > 0) | ||
| 138 | * x_calc = calcX(s, R, p); | ||
| 139 | * X = max(min(X_calc, 2 * X_recv), s / t_mbi); | ||
| 140 | * Else | ||
| 141 | * If (now - tld >= R) | ||
| 142 | * X = max(min(2 * X, 2 * X_recv), s / R); | ||
| 143 | * tld = now; | ||
| 144 | */ | ||
| 145 | static void ccid3_hc_tx_update_x(struct sock *sk) | ||
| 146 | { | ||
| 147 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 148 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 149 | |||
| 150 | /* To avoid large error in calcX */ | ||
| 151 | if (hctx->ccid3hctx_p >= TFRC_SMALLEST_P) { | ||
| 152 | hctx->ccid3hctx_x_calc = tfrc_calc_x(hctx->ccid3hctx_s, | ||
| 153 | hctx->ccid3hctx_rtt, | ||
| 154 | hctx->ccid3hctx_p); | ||
| 155 | hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_calc, | ||
| 156 | 2 * hctx->ccid3hctx_x_recv), | ||
| 157 | (hctx->ccid3hctx_s / | ||
| 158 | TFRC_MAX_BACK_OFF_TIME)); | ||
| 159 | } else { | ||
| 160 | struct timeval now; | ||
| 161 | |||
| 162 | do_gettimeofday(&now); | ||
| 163 | if (timeval_delta(&now, &hctx->ccid3hctx_t_ld) >= | ||
| 164 | hctx->ccid3hctx_rtt) { | ||
| 165 | hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_recv, | ||
| 166 | hctx->ccid3hctx_x) * 2, | ||
| 167 | usecs_div(hctx->ccid3hctx_s, | ||
| 168 | hctx->ccid3hctx_rtt)); | ||
| 169 | hctx->ccid3hctx_t_ld = now; | ||
| 170 | } | ||
| 171 | } | ||
| 172 | } | ||
| 173 | |||
| 174 | static void ccid3_hc_tx_no_feedback_timer(unsigned long data) | ||
| 175 | { | ||
| 176 | struct sock *sk = (struct sock *)data; | ||
| 177 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 178 | unsigned long next_tmout = 0; | ||
| 179 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 180 | |||
| 181 | bh_lock_sock(sk); | ||
| 182 | if (sock_owned_by_user(sk)) { | ||
| 183 | /* Try again later. */ | ||
| 184 | /* XXX: set some sensible MIB */ | ||
| 185 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | ||
| 186 | jiffies + HZ / 5); | ||
| 187 | goto out; | ||
| 188 | } | ||
| 189 | |||
| 190 | ccid3_pr_debug("%s, sk=%p, state=%s\n", dccp_role(sk), sk, | ||
| 191 | ccid3_tx_state_name(hctx->ccid3hctx_state)); | ||
| 192 | |||
| 193 | switch (hctx->ccid3hctx_state) { | ||
| 194 | case TFRC_SSTATE_TERM: | ||
| 195 | goto out; | ||
| 196 | case TFRC_SSTATE_NO_FBACK: | ||
| 197 | /* Halve send rate */ | ||
| 198 | hctx->ccid3hctx_x /= 2; | ||
| 199 | if (hctx->ccid3hctx_x < (hctx->ccid3hctx_s / | ||
| 200 | TFRC_MAX_BACK_OFF_TIME)) | ||
| 201 | hctx->ccid3hctx_x = (hctx->ccid3hctx_s / | ||
| 202 | TFRC_MAX_BACK_OFF_TIME); | ||
| 203 | |||
| 204 | ccid3_pr_debug("%s, sk=%p, state=%s, updated tx rate to %d " | ||
| 205 | "bytes/s\n", | ||
| 206 | dccp_role(sk), sk, | ||
| 207 | ccid3_tx_state_name(hctx->ccid3hctx_state), | ||
| 208 | hctx->ccid3hctx_x); | ||
| 209 | next_tmout = max_t(u32, 2 * usecs_div(hctx->ccid3hctx_s, | ||
| 210 | hctx->ccid3hctx_x), | ||
| 211 | TFRC_INITIAL_TIMEOUT); | ||
| 212 | /* | ||
| 213 | * FIXME - not sure above calculation is correct. See section | ||
| 214 | * 5 of CCID3 11 should adjust tx_t_ipi and double that to | ||
| 215 | * achieve it really | ||
| 216 | */ | ||
| 217 | break; | ||
| 218 | case TFRC_SSTATE_FBACK: | ||
| 219 | /* | ||
| 220 | * Check if IDLE since last timeout and recv rate is less than | ||
| 221 | * 4 packets per RTT | ||
| 222 | */ | ||
| 223 | if (!hctx->ccid3hctx_idle || | ||
| 224 | (hctx->ccid3hctx_x_recv >= | ||
| 225 | 4 * usecs_div(hctx->ccid3hctx_s, hctx->ccid3hctx_rtt))) { | ||
| 226 | ccid3_pr_debug("%s, sk=%p, state=%s, not idle\n", | ||
| 227 | dccp_role(sk), sk, | ||
| 228 | ccid3_tx_state_name(hctx->ccid3hctx_state)); | ||
| 229 | /* Halve sending rate */ | ||
| 230 | |||
| 231 | /* If (X_calc > 2 * X_recv) | ||
| 232 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); | ||
| 233 | * Else | ||
| 234 | * X_recv = X_calc / 4; | ||
| 235 | */ | ||
| 236 | BUG_ON(hctx->ccid3hctx_p >= TFRC_SMALLEST_P && | ||
| 237 | hctx->ccid3hctx_x_calc == 0); | ||
| 238 | |||
| 239 | /* check also if p is zero -> x_calc is infinity? */ | ||
| 240 | if (hctx->ccid3hctx_p < TFRC_SMALLEST_P || | ||
| 241 | hctx->ccid3hctx_x_calc > 2 * hctx->ccid3hctx_x_recv) | ||
| 242 | hctx->ccid3hctx_x_recv = max_t(u32, hctx->ccid3hctx_x_recv / 2, | ||
| 243 | hctx->ccid3hctx_s / (2 * TFRC_MAX_BACK_OFF_TIME)); | ||
| 244 | else | ||
| 245 | hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc / 4; | ||
| 246 | |||
| 247 | /* Update sending rate */ | ||
| 248 | ccid3_hc_tx_update_x(sk); | ||
| 249 | } | ||
| 250 | /* | ||
| 251 | * Schedule no feedback timer to expire in | ||
| 252 | * max(4 * R, 2 * s / X) | ||
| 253 | */ | ||
| 254 | next_tmout = max_t(u32, hctx->ccid3hctx_t_rto, | ||
| 255 | 2 * usecs_div(hctx->ccid3hctx_s, | ||
| 256 | hctx->ccid3hctx_x)); | ||
| 257 | break; | ||
| 258 | default: | ||
| 259 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | ||
| 260 | __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); | ||
| 261 | dump_stack(); | ||
| 262 | goto out; | ||
| 263 | } | ||
| 264 | |||
| 265 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | ||
| 266 | jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout))); | ||
| 267 | hctx->ccid3hctx_idle = 1; | ||
| 268 | out: | ||
| 269 | bh_unlock_sock(sk); | ||
| 270 | sock_put(sk); | ||
| 271 | } | ||
| 272 | |||
| 273 | static int ccid3_hc_tx_send_packet(struct sock *sk, | ||
| 274 | struct sk_buff *skb, int len) | ||
| 275 | { | ||
| 276 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 277 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 278 | struct dccp_tx_hist_entry *new_packet; | ||
| 279 | struct timeval now; | ||
| 280 | long delay; | ||
| 281 | int rc = -ENOTCONN; | ||
| 282 | |||
| 283 | /* Check if pure ACK or Terminating*/ | ||
| 284 | |||
| 285 | /* | ||
| 286 | * XXX: We only call this function for DATA and DATAACK, on, these | ||
| 287 | * packets can have zero length, but why the comment about "pure ACK"? | ||
| 288 | */ | ||
| 289 | if (hctx == NULL || len == 0 || | ||
| 290 | hctx->ccid3hctx_state == TFRC_SSTATE_TERM) | ||
| 291 | goto out; | ||
| 292 | |||
| 293 | /* See if last packet allocated was not sent */ | ||
| 294 | new_packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist); | ||
| 295 | if (new_packet == NULL || new_packet->dccphtx_sent) { | ||
| 296 | new_packet = dccp_tx_hist_entry_new(ccid3_tx_hist, | ||
| 297 | SLAB_ATOMIC); | ||
| 298 | |||
| 299 | rc = -ENOBUFS; | ||
| 300 | if (new_packet == NULL) { | ||
| 301 | ccid3_pr_debug("%s, sk=%p, not enough mem to add " | ||
| 302 | "to history, send refused\n", | ||
| 303 | dccp_role(sk), sk); | ||
| 304 | goto out; | ||
| 305 | } | ||
| 306 | |||
| 307 | dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, new_packet); | ||
| 308 | } | ||
| 309 | |||
| 310 | do_gettimeofday(&now); | ||
| 311 | |||
| 312 | switch (hctx->ccid3hctx_state) { | ||
| 313 | case TFRC_SSTATE_NO_SENT: | ||
| 314 | ccid3_pr_debug("%s, sk=%p, first packet(%llu)\n", | ||
| 315 | dccp_role(sk), sk, dp->dccps_gss); | ||
| 316 | |||
| 317 | hctx->ccid3hctx_no_feedback_timer.function = ccid3_hc_tx_no_feedback_timer; | ||
| 318 | hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk; | ||
| 319 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | ||
| 320 | jiffies + usecs_to_jiffies(TFRC_INITIAL_TIMEOUT)); | ||
| 321 | hctx->ccid3hctx_last_win_count = 0; | ||
| 322 | hctx->ccid3hctx_t_last_win_count = now; | ||
| 323 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); | ||
| 324 | hctx->ccid3hctx_t_ipi = TFRC_INITIAL_TIMEOUT; | ||
| 325 | |||
| 326 | /* Set nominal send time for initial packet */ | ||
| 327 | hctx->ccid3hctx_t_nom = now; | ||
| 328 | timeval_add_usecs(&hctx->ccid3hctx_t_nom, | ||
| 329 | hctx->ccid3hctx_t_ipi); | ||
| 330 | ccid3_calc_new_delta(hctx); | ||
| 331 | rc = 0; | ||
| 332 | break; | ||
| 333 | case TFRC_SSTATE_NO_FBACK: | ||
| 334 | case TFRC_SSTATE_FBACK: | ||
| 335 | delay = (timeval_delta(&now, &hctx->ccid3hctx_t_nom) - | ||
| 336 | hctx->ccid3hctx_delta); | ||
| 337 | ccid3_pr_debug("send_packet delay=%ld\n", delay); | ||
| 338 | delay /= -1000; | ||
| 339 | /* divide by -1000 is to convert to ms and get sign right */ | ||
| 340 | rc = delay > 0 ? delay : 0; | ||
| 341 | break; | ||
| 342 | default: | ||
| 343 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | ||
| 344 | __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); | ||
| 345 | dump_stack(); | ||
| 346 | rc = -EINVAL; | ||
| 347 | break; | ||
| 348 | } | ||
| 349 | |||
| 350 | /* Can we send? if so add options and add to packet history */ | ||
| 351 | if (rc == 0) | ||
| 352 | new_packet->dccphtx_ccval = | ||
| 353 | DCCP_SKB_CB(skb)->dccpd_ccval = | ||
| 354 | hctx->ccid3hctx_last_win_count; | ||
| 355 | out: | ||
| 356 | return rc; | ||
| 357 | } | ||
| 358 | |||
| 359 | static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, int len) | ||
| 360 | { | ||
| 361 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 362 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 363 | struct timeval now; | ||
| 364 | |||
| 365 | BUG_ON(hctx == NULL); | ||
| 366 | |||
| 367 | if (hctx->ccid3hctx_state == TFRC_SSTATE_TERM) { | ||
| 368 | ccid3_pr_debug("%s, sk=%p, while state is TFRC_SSTATE_TERM!\n", | ||
| 369 | dccp_role(sk), sk); | ||
| 370 | return; | ||
| 371 | } | ||
| 372 | |||
| 373 | do_gettimeofday(&now); | ||
| 374 | |||
| 375 | /* check if we have sent a data packet */ | ||
| 376 | if (len > 0) { | ||
| 377 | unsigned long quarter_rtt; | ||
| 378 | struct dccp_tx_hist_entry *packet; | ||
| 379 | |||
| 380 | packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist); | ||
| 381 | if (packet == NULL) { | ||
| 382 | printk(KERN_CRIT "%s: packet doesn't exists in " | ||
| 383 | "history!\n", __FUNCTION__); | ||
| 384 | return; | ||
| 385 | } | ||
| 386 | if (packet->dccphtx_sent) { | ||
| 387 | printk(KERN_CRIT "%s: no unsent packet in history!\n", | ||
| 388 | __FUNCTION__); | ||
| 389 | return; | ||
| 390 | } | ||
| 391 | packet->dccphtx_tstamp = now; | ||
| 392 | packet->dccphtx_seqno = dp->dccps_gss; | ||
| 393 | /* | ||
| 394 | * Check if win_count have changed | ||
| 395 | * Algorithm in "8.1. Window Counter Valuer" in | ||
| 396 | * draft-ietf-dccp-ccid3-11.txt | ||
| 397 | */ | ||
| 398 | quarter_rtt = timeval_delta(&now, &hctx->ccid3hctx_t_last_win_count); | ||
| 399 | if (likely(hctx->ccid3hctx_rtt > 8)) | ||
| 400 | quarter_rtt /= hctx->ccid3hctx_rtt / 4; | ||
| 401 | |||
| 402 | if (quarter_rtt > 0) { | ||
| 403 | hctx->ccid3hctx_t_last_win_count = now; | ||
| 404 | hctx->ccid3hctx_last_win_count = (hctx->ccid3hctx_last_win_count + | ||
| 405 | min_t(unsigned long, quarter_rtt, 5)) % 16; | ||
| 406 | ccid3_pr_debug("%s, sk=%p, window changed from " | ||
| 407 | "%u to %u!\n", | ||
| 408 | dccp_role(sk), sk, | ||
| 409 | packet->dccphtx_ccval, | ||
| 410 | hctx->ccid3hctx_last_win_count); | ||
| 411 | } | ||
| 412 | |||
| 413 | hctx->ccid3hctx_idle = 0; | ||
| 414 | packet->dccphtx_rtt = hctx->ccid3hctx_rtt; | ||
| 415 | packet->dccphtx_sent = 1; | ||
| 416 | } else | ||
| 417 | ccid3_pr_debug("%s, sk=%p, seqno=%llu NOT inserted!\n", | ||
| 418 | dccp_role(sk), sk, dp->dccps_gss); | ||
| 419 | |||
| 420 | switch (hctx->ccid3hctx_state) { | ||
| 421 | case TFRC_SSTATE_NO_SENT: | ||
| 422 | /* if first wasn't pure ack */ | ||
| 423 | if (len != 0) | ||
| 424 | printk(KERN_CRIT "%s: %s, First packet sent is noted " | ||
| 425 | "as a data packet\n", | ||
| 426 | __FUNCTION__, dccp_role(sk)); | ||
| 427 | return; | ||
| 428 | case TFRC_SSTATE_NO_FBACK: | ||
| 429 | case TFRC_SSTATE_FBACK: | ||
| 430 | if (len > 0) { | ||
| 431 | hctx->ccid3hctx_t_nom = now; | ||
| 432 | ccid3_calc_new_t_ipi(hctx); | ||
| 433 | ccid3_calc_new_delta(hctx); | ||
| 434 | timeval_add_usecs(&hctx->ccid3hctx_t_nom, | ||
| 435 | hctx->ccid3hctx_t_ipi); | ||
| 436 | } | ||
| 437 | break; | ||
| 438 | default: | ||
| 439 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | ||
| 440 | __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); | ||
| 441 | dump_stack(); | ||
| 442 | break; | ||
| 443 | } | ||
| 444 | } | ||
| 445 | |||
| 446 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) | ||
| 447 | { | ||
| 448 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 449 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 450 | struct ccid3_options_received *opt_recv; | ||
| 451 | struct dccp_tx_hist_entry *packet; | ||
| 452 | unsigned long next_tmout; | ||
| 453 | u32 t_elapsed; | ||
| 454 | u32 pinv; | ||
| 455 | u32 x_recv; | ||
| 456 | u32 r_sample; | ||
| 457 | |||
| 458 | if (hctx == NULL) | ||
| 459 | return; | ||
| 460 | |||
| 461 | if (hctx->ccid3hctx_state == TFRC_SSTATE_TERM) { | ||
| 462 | ccid3_pr_debug("%s, sk=%p, received a packet when " | ||
| 463 | "terminating!\n", dccp_role(sk), sk); | ||
| 464 | return; | ||
| 465 | } | ||
| 466 | |||
| 467 | /* we are only interested in ACKs */ | ||
| 468 | if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || | ||
| 469 | DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) | ||
| 470 | return; | ||
| 471 | |||
| 472 | opt_recv = &hctx->ccid3hctx_options_received; | ||
| 473 | |||
| 474 | t_elapsed = dp->dccps_options_received.dccpor_elapsed_time; | ||
| 475 | x_recv = opt_recv->ccid3or_receive_rate; | ||
| 476 | pinv = opt_recv->ccid3or_loss_event_rate; | ||
| 477 | |||
| 478 | switch (hctx->ccid3hctx_state) { | ||
| 479 | case TFRC_SSTATE_NO_SENT: | ||
| 480 | /* FIXME: what to do here? */ | ||
| 481 | return; | ||
| 482 | case TFRC_SSTATE_NO_FBACK: | ||
| 483 | case TFRC_SSTATE_FBACK: | ||
| 484 | /* Calculate new round trip sample by | ||
| 485 | * R_sample = (now - t_recvdata) - t_delay */ | ||
| 486 | /* get t_recvdata from history */ | ||
| 487 | packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist, | ||
| 488 | DCCP_SKB_CB(skb)->dccpd_ack_seq); | ||
| 489 | if (packet == NULL) { | ||
| 490 | ccid3_pr_debug("%s, sk=%p, seqno %llu(%s) does't " | ||
| 491 | "exist in history!\n", | ||
| 492 | dccp_role(sk), sk, | ||
| 493 | DCCP_SKB_CB(skb)->dccpd_ack_seq, | ||
| 494 | dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type)); | ||
| 495 | return; | ||
| 496 | } | ||
| 497 | |||
| 498 | /* Update RTT */ | ||
| 499 | r_sample = timeval_now_delta(&packet->dccphtx_tstamp); | ||
| 500 | /* FIXME: */ | ||
| 501 | // r_sample -= usecs_to_jiffies(t_elapsed * 10); | ||
| 502 | |||
| 503 | /* Update RTT estimate by | ||
| 504 | * If (No feedback recv) | ||
| 505 | * R = R_sample; | ||
| 506 | * Else | ||
| 507 | * R = q * R + (1 - q) * R_sample; | ||
| 508 | * | ||
| 509 | * q is a constant, RFC 3448 recomments 0.9 | ||
| 510 | */ | ||
| 511 | if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) { | ||
| 512 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); | ||
| 513 | hctx->ccid3hctx_rtt = r_sample; | ||
| 514 | } else | ||
| 515 | hctx->ccid3hctx_rtt = (hctx->ccid3hctx_rtt * 9) / 10 + | ||
| 516 | r_sample / 10; | ||
| 517 | |||
| 518 | ccid3_pr_debug("%s, sk=%p, New RTT estimate=%uus, " | ||
| 519 | "r_sample=%us\n", dccp_role(sk), sk, | ||
| 520 | hctx->ccid3hctx_rtt, r_sample); | ||
| 521 | |||
| 522 | /* Update timeout interval */ | ||
| 523 | hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt, | ||
| 524 | USEC_PER_SEC); | ||
| 525 | |||
| 526 | /* Update receive rate */ | ||
| 527 | hctx->ccid3hctx_x_recv = x_recv;/* X_recv in bytes per sec */ | ||
| 528 | |||
| 529 | /* Update loss event rate */ | ||
| 530 | if (pinv == ~0 || pinv == 0) | ||
| 531 | hctx->ccid3hctx_p = 0; | ||
| 532 | else { | ||
| 533 | hctx->ccid3hctx_p = 1000000 / pinv; | ||
| 534 | |||
| 535 | if (hctx->ccid3hctx_p < TFRC_SMALLEST_P) { | ||
| 536 | hctx->ccid3hctx_p = TFRC_SMALLEST_P; | ||
| 537 | ccid3_pr_debug("%s, sk=%p, Smallest p used!\n", | ||
| 538 | dccp_role(sk), sk); | ||
| 539 | } | ||
| 540 | } | ||
| 541 | |||
| 542 | /* unschedule no feedback timer */ | ||
| 543 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); | ||
| 544 | |||
| 545 | /* Update sending rate */ | ||
| 546 | ccid3_hc_tx_update_x(sk); | ||
| 547 | |||
| 548 | /* Update next send time */ | ||
| 549 | timeval_sub_usecs(&hctx->ccid3hctx_t_nom, | ||
| 550 | hctx->ccid3hctx_t_ipi); | ||
| 551 | ccid3_calc_new_t_ipi(hctx); | ||
| 552 | timeval_add_usecs(&hctx->ccid3hctx_t_nom, | ||
| 553 | hctx->ccid3hctx_t_ipi); | ||
| 554 | ccid3_calc_new_delta(hctx); | ||
| 555 | |||
| 556 | /* remove all packets older than the one acked from history */ | ||
| 557 | dccp_tx_hist_purge_older(ccid3_tx_hist, | ||
| 558 | &hctx->ccid3hctx_hist, packet); | ||
| 559 | /* | ||
| 560 | * As we have calculated new ipi, delta, t_nom it is possible that | ||
| 561 | * we now can send a packet, so wake up dccp_wait_for_ccids. | ||
| 562 | */ | ||
| 563 | sk->sk_write_space(sk); | ||
| 564 | |||
| 565 | /* | ||
| 566 | * Schedule no feedback timer to expire in | ||
| 567 | * max(4 * R, 2 * s / X) | ||
| 568 | */ | ||
| 569 | next_tmout = max(hctx->ccid3hctx_t_rto, | ||
| 570 | 2 * usecs_div(hctx->ccid3hctx_s, | ||
| 571 | hctx->ccid3hctx_x)); | ||
| 572 | |||
| 573 | ccid3_pr_debug("%s, sk=%p, Scheduled no feedback timer to " | ||
| 574 | "expire in %lu jiffies (%luus)\n", | ||
| 575 | dccp_role(sk), sk, | ||
| 576 | usecs_to_jiffies(next_tmout), next_tmout); | ||
| 577 | |||
| 578 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | ||
| 579 | jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout))); | ||
| 580 | |||
| 581 | /* set idle flag */ | ||
| 582 | hctx->ccid3hctx_idle = 1; | ||
| 583 | break; | ||
| 584 | default: | ||
| 585 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | ||
| 586 | __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); | ||
| 587 | dump_stack(); | ||
| 588 | break; | ||
| 589 | } | ||
| 590 | } | ||
| 591 | |||
| 592 | static void ccid3_hc_tx_insert_options(struct sock *sk, struct sk_buff *skb) | ||
| 593 | { | ||
| 594 | const struct dccp_sock *dp = dccp_sk(sk); | ||
| 595 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 596 | |||
| 597 | if (hctx == NULL || !(sk->sk_state == DCCP_OPEN || | ||
| 598 | sk->sk_state == DCCP_PARTOPEN)) | ||
| 599 | return; | ||
| 600 | |||
| 601 | DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; | ||
| 602 | } | ||
| 603 | |||
| 604 | static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, | ||
| 605 | unsigned char len, u16 idx, | ||
| 606 | unsigned char *value) | ||
| 607 | { | ||
| 608 | int rc = 0; | ||
| 609 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 610 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 611 | struct ccid3_options_received *opt_recv; | ||
| 612 | |||
| 613 | if (hctx == NULL) | ||
| 614 | return 0; | ||
| 615 | |||
| 616 | opt_recv = &hctx->ccid3hctx_options_received; | ||
| 617 | |||
| 618 | if (opt_recv->ccid3or_seqno != dp->dccps_gsr) { | ||
| 619 | opt_recv->ccid3or_seqno = dp->dccps_gsr; | ||
| 620 | opt_recv->ccid3or_loss_event_rate = ~0; | ||
| 621 | opt_recv->ccid3or_loss_intervals_idx = 0; | ||
| 622 | opt_recv->ccid3or_loss_intervals_len = 0; | ||
| 623 | opt_recv->ccid3or_receive_rate = 0; | ||
| 624 | } | ||
| 625 | |||
| 626 | switch (option) { | ||
| 627 | case TFRC_OPT_LOSS_EVENT_RATE: | ||
| 628 | if (len != 4) { | ||
| 629 | ccid3_pr_debug("%s, sk=%p, invalid len for " | ||
| 630 | "TFRC_OPT_LOSS_EVENT_RATE\n", | ||
| 631 | dccp_role(sk), sk); | ||
| 632 | rc = -EINVAL; | ||
| 633 | } else { | ||
| 634 | opt_recv->ccid3or_loss_event_rate = ntohl(*(u32 *)value); | ||
| 635 | ccid3_pr_debug("%s, sk=%p, LOSS_EVENT_RATE=%u\n", | ||
| 636 | dccp_role(sk), sk, | ||
| 637 | opt_recv->ccid3or_loss_event_rate); | ||
| 638 | } | ||
| 639 | break; | ||
| 640 | case TFRC_OPT_LOSS_INTERVALS: | ||
| 641 | opt_recv->ccid3or_loss_intervals_idx = idx; | ||
| 642 | opt_recv->ccid3or_loss_intervals_len = len; | ||
| 643 | ccid3_pr_debug("%s, sk=%p, LOSS_INTERVALS=(%u, %u)\n", | ||
| 644 | dccp_role(sk), sk, | ||
| 645 | opt_recv->ccid3or_loss_intervals_idx, | ||
| 646 | opt_recv->ccid3or_loss_intervals_len); | ||
| 647 | break; | ||
| 648 | case TFRC_OPT_RECEIVE_RATE: | ||
| 649 | if (len != 4) { | ||
| 650 | ccid3_pr_debug("%s, sk=%p, invalid len for " | ||
| 651 | "TFRC_OPT_RECEIVE_RATE\n", | ||
| 652 | dccp_role(sk), sk); | ||
| 653 | rc = -EINVAL; | ||
| 654 | } else { | ||
| 655 | opt_recv->ccid3or_receive_rate = ntohl(*(u32 *)value); | ||
| 656 | ccid3_pr_debug("%s, sk=%p, RECEIVE_RATE=%u\n", | ||
| 657 | dccp_role(sk), sk, | ||
| 658 | opt_recv->ccid3or_receive_rate); | ||
| 659 | } | ||
| 660 | break; | ||
| 661 | } | ||
| 662 | |||
| 663 | return rc; | ||
| 664 | } | ||
| 665 | |||
| 666 | static int ccid3_hc_tx_init(struct sock *sk) | ||
| 667 | { | ||
| 668 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 669 | struct ccid3_hc_tx_sock *hctx; | ||
| 670 | |||
| 671 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | ||
| 672 | |||
| 673 | hctx = dp->dccps_hc_tx_ccid_private = kmalloc(sizeof(*hctx), | ||
| 674 | gfp_any()); | ||
| 675 | if (hctx == NULL) | ||
| 676 | return -ENOMEM; | ||
| 677 | |||
| 678 | memset(hctx, 0, sizeof(*hctx)); | ||
| 679 | |||
| 680 | if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE && | ||
| 681 | dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE) | ||
| 682 | hctx->ccid3hctx_s = dp->dccps_packet_size; | ||
| 683 | else | ||
| 684 | hctx->ccid3hctx_s = TFRC_STD_PACKET_SIZE; | ||
| 685 | |||
| 686 | /* Set transmission rate to 1 packet per second */ | ||
| 687 | hctx->ccid3hctx_x = hctx->ccid3hctx_s; | ||
| 688 | hctx->ccid3hctx_t_rto = USEC_PER_SEC; | ||
| 689 | hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT; | ||
| 690 | INIT_LIST_HEAD(&hctx->ccid3hctx_hist); | ||
| 691 | init_timer(&hctx->ccid3hctx_no_feedback_timer); | ||
| 692 | |||
| 693 | return 0; | ||
| 694 | } | ||
| 695 | |||
| 696 | static void ccid3_hc_tx_exit(struct sock *sk) | ||
| 697 | { | ||
| 698 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 699 | struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 700 | |||
| 701 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | ||
| 702 | BUG_ON(hctx == NULL); | ||
| 703 | |||
| 704 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM); | ||
| 705 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); | ||
| 706 | |||
| 707 | /* Empty packet history */ | ||
| 708 | dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist); | ||
| 709 | |||
| 710 | kfree(dp->dccps_hc_tx_ccid_private); | ||
| 711 | dp->dccps_hc_tx_ccid_private = NULL; | ||
| 712 | } | ||
| 713 | |||
| 714 | /* | ||
| 715 | * RX Half Connection methods | ||
| 716 | */ | ||
| 717 | |||
| 718 | /* TFRC receiver states */ | ||
| 719 | enum ccid3_hc_rx_states { | ||
| 720 | TFRC_RSTATE_NO_DATA = 1, | ||
| 721 | TFRC_RSTATE_DATA, | ||
| 722 | TFRC_RSTATE_TERM = 127, | ||
| 723 | }; | ||
| 724 | |||
| 725 | #ifdef CCID3_DEBUG | ||
| 726 | static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) | ||
| 727 | { | ||
| 728 | static char *ccid3_rx_state_names[] = { | ||
| 729 | [TFRC_RSTATE_NO_DATA] = "NO_DATA", | ||
| 730 | [TFRC_RSTATE_DATA] = "DATA", | ||
| 731 | [TFRC_RSTATE_TERM] = "TERM", | ||
| 732 | }; | ||
| 733 | |||
| 734 | return ccid3_rx_state_names[state]; | ||
| 735 | } | ||
| 736 | #endif | ||
| 737 | |||
| 738 | static inline void ccid3_hc_rx_set_state(struct sock *sk, | ||
| 739 | enum ccid3_hc_rx_states state) | ||
| 740 | { | ||
| 741 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 742 | struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 743 | enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state; | ||
| 744 | |||
| 745 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", | ||
| 746 | dccp_role(sk), sk, ccid3_rx_state_name(oldstate), | ||
| 747 | ccid3_rx_state_name(state)); | ||
| 748 | WARN_ON(state == oldstate); | ||
| 749 | hcrx->ccid3hcrx_state = state; | ||
| 750 | } | ||
| 751 | |||
| 752 | static void ccid3_hc_rx_send_feedback(struct sock *sk) | ||
| 753 | { | ||
| 754 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 755 | struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 756 | struct dccp_rx_hist_entry *packet; | ||
| 757 | struct timeval now; | ||
| 758 | |||
| 759 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | ||
| 760 | |||
| 761 | do_gettimeofday(&now); | ||
| 762 | |||
| 763 | switch (hcrx->ccid3hcrx_state) { | ||
| 764 | case TFRC_RSTATE_NO_DATA: | ||
| 765 | hcrx->ccid3hcrx_x_recv = 0; | ||
| 766 | break; | ||
| 767 | case TFRC_RSTATE_DATA: { | ||
| 768 | const u32 delta = timeval_delta(&now, | ||
| 769 | &hcrx->ccid3hcrx_tstamp_last_feedback); | ||
| 770 | |||
| 771 | hcrx->ccid3hcrx_x_recv = (hcrx->ccid3hcrx_bytes_recv * | ||
| 772 | USEC_PER_SEC); | ||
| 773 | if (likely(delta > 1)) | ||
| 774 | hcrx->ccid3hcrx_x_recv /= delta; | ||
| 775 | } | ||
| 776 | break; | ||
| 777 | default: | ||
| 778 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | ||
| 779 | __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state); | ||
| 780 | dump_stack(); | ||
| 781 | return; | ||
| 782 | } | ||
| 783 | |||
| 784 | packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist); | ||
| 785 | if (packet == NULL) { | ||
| 786 | printk(KERN_CRIT "%s: %s, sk=%p, no data packet in history!\n", | ||
| 787 | __FUNCTION__, dccp_role(sk), sk); | ||
| 788 | dump_stack(); | ||
| 789 | return; | ||
| 790 | } | ||
| 791 | |||
| 792 | hcrx->ccid3hcrx_tstamp_last_feedback = now; | ||
| 793 | hcrx->ccid3hcrx_last_counter = packet->dccphrx_ccval; | ||
| 794 | hcrx->ccid3hcrx_seqno_last_counter = packet->dccphrx_seqno; | ||
| 795 | hcrx->ccid3hcrx_bytes_recv = 0; | ||
| 796 | |||
| 797 | /* Convert to multiples of 10us */ | ||
| 798 | hcrx->ccid3hcrx_elapsed_time = | ||
| 799 | timeval_delta(&now, &packet->dccphrx_tstamp) / 10; | ||
| 800 | if (hcrx->ccid3hcrx_p == 0) | ||
| 801 | hcrx->ccid3hcrx_pinv = ~0; | ||
| 802 | else | ||
| 803 | hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p; | ||
| 804 | dccp_send_ack(sk); | ||
| 805 | } | ||
| 806 | |||
| 807 | static void ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) | ||
| 808 | { | ||
| 809 | const struct dccp_sock *dp = dccp_sk(sk); | ||
| 810 | u32 x_recv, pinv; | ||
| 811 | struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 812 | |||
| 813 | if (hcrx == NULL || !(sk->sk_state == DCCP_OPEN || | ||
| 814 | sk->sk_state == DCCP_PARTOPEN)) | ||
| 815 | return; | ||
| 816 | |||
| 817 | DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_last_counter; | ||
| 818 | |||
| 819 | if (dccp_packet_without_ack(skb)) | ||
| 820 | return; | ||
| 821 | |||
| 822 | if (hcrx->ccid3hcrx_elapsed_time != 0) | ||
| 823 | dccp_insert_option_elapsed_time(sk, skb, | ||
| 824 | hcrx->ccid3hcrx_elapsed_time); | ||
| 825 | dccp_insert_option_timestamp(sk, skb); | ||
| 826 | x_recv = htonl(hcrx->ccid3hcrx_x_recv); | ||
| 827 | pinv = htonl(hcrx->ccid3hcrx_pinv); | ||
| 828 | dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE, | ||
| 829 | &pinv, sizeof(pinv)); | ||
| 830 | dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE, | ||
| 831 | &x_recv, sizeof(x_recv)); | ||
| 832 | } | ||
| 833 | |||
| 834 | /* calculate first loss interval | ||
| 835 | * | ||
| 836 | * returns estimated loss interval in usecs */ | ||
| 837 | |||
| 838 | static u32 ccid3_hc_rx_calc_first_li(struct sock *sk) | ||
| 839 | { | ||
| 840 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 841 | struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 842 | struct dccp_rx_hist_entry *entry, *next, *tail = NULL; | ||
| 843 | u32 rtt, delta, x_recv, fval, p, tmp2; | ||
| 844 | struct timeval tstamp = { 0, }; | ||
| 845 | int interval = 0; | ||
| 846 | int win_count = 0; | ||
| 847 | int step = 0; | ||
| 848 | u64 tmp1; | ||
| 849 | |||
| 850 | list_for_each_entry_safe(entry, next, &hcrx->ccid3hcrx_hist, | ||
| 851 | dccphrx_node) { | ||
| 852 | if (dccp_rx_hist_entry_data_packet(entry)) { | ||
| 853 | tail = entry; | ||
| 854 | |||
| 855 | switch (step) { | ||
| 856 | case 0: | ||
| 857 | tstamp = entry->dccphrx_tstamp; | ||
| 858 | win_count = entry->dccphrx_ccval; | ||
| 859 | step = 1; | ||
| 860 | break; | ||
| 861 | case 1: | ||
| 862 | interval = win_count - entry->dccphrx_ccval; | ||
| 863 | if (interval < 0) | ||
| 864 | interval += TFRC_WIN_COUNT_LIMIT; | ||
| 865 | if (interval > 4) | ||
| 866 | goto found; | ||
| 867 | break; | ||
| 868 | } | ||
| 869 | } | ||
| 870 | } | ||
| 871 | |||
| 872 | if (step == 0) { | ||
| 873 | printk(KERN_CRIT "%s: %s, sk=%p, packet history contains no " | ||
| 874 | "data packets!\n", | ||
| 875 | __FUNCTION__, dccp_role(sk), sk); | ||
| 876 | return ~0; | ||
| 877 | } | ||
| 878 | |||
| 879 | if (interval == 0) { | ||
| 880 | ccid3_pr_debug("%s, sk=%p, Could not find a win_count " | ||
| 881 | "interval > 0. Defaulting to 1\n", | ||
| 882 | dccp_role(sk), sk); | ||
| 883 | interval = 1; | ||
| 884 | } | ||
| 885 | found: | ||
| 886 | rtt = timeval_delta(&tstamp, &tail->dccphrx_tstamp) * 4 / interval; | ||
| 887 | ccid3_pr_debug("%s, sk=%p, approximated RTT to %uus\n", | ||
| 888 | dccp_role(sk), sk, rtt); | ||
| 889 | if (rtt == 0) | ||
| 890 | rtt = 1; | ||
| 891 | |||
| 892 | delta = timeval_now_delta(&hcrx->ccid3hcrx_tstamp_last_feedback); | ||
| 893 | x_recv = hcrx->ccid3hcrx_bytes_recv * USEC_PER_SEC; | ||
| 894 | if (likely(delta > 1)) | ||
| 895 | x_recv /= delta; | ||
| 896 | |||
| 897 | tmp1 = (u64)x_recv * (u64)rtt; | ||
| 898 | do_div(tmp1,10000000); | ||
| 899 | tmp2 = (u32)tmp1; | ||
| 900 | fval = (hcrx->ccid3hcrx_s * 100000) / tmp2; | ||
| 901 | /* do not alter order above or you will get overflow on 32 bit */ | ||
| 902 | p = tfrc_calc_x_reverse_lookup(fval); | ||
| 903 | ccid3_pr_debug("%s, sk=%p, receive rate=%u bytes/s, implied " | ||
| 904 | "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); | ||
| 905 | |||
| 906 | if (p == 0) | ||
| 907 | return ~0; | ||
| 908 | else | ||
| 909 | return 1000000 / p; | ||
| 910 | } | ||
| 911 | |||
| 912 | static void ccid3_hc_rx_update_li(struct sock *sk, u64 seq_loss, u8 win_loss) | ||
| 913 | { | ||
| 914 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 915 | struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 916 | |||
| 917 | if (seq_loss != DCCP_MAX_SEQNO + 1 && | ||
| 918 | list_empty(&hcrx->ccid3hcrx_li_hist)) { | ||
| 919 | struct dccp_li_hist_entry *li_tail; | ||
| 920 | |||
| 921 | li_tail = dccp_li_hist_interval_new(ccid3_li_hist, | ||
| 922 | &hcrx->ccid3hcrx_li_hist, | ||
| 923 | seq_loss, win_loss); | ||
| 924 | if (li_tail == NULL) | ||
| 925 | return; | ||
| 926 | li_tail->dccplih_interval = ccid3_hc_rx_calc_first_li(sk); | ||
| 927 | } | ||
| 928 | /* FIXME: find end of interval */ | ||
| 929 | } | ||
| 930 | |||
| 931 | static void ccid3_hc_rx_detect_loss(struct sock *sk) | ||
| 932 | { | ||
| 933 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 934 | struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 935 | u8 win_loss; | ||
| 936 | const u64 seq_loss = dccp_rx_hist_detect_loss(&hcrx->ccid3hcrx_hist, | ||
| 937 | &hcrx->ccid3hcrx_li_hist, | ||
| 938 | &win_loss); | ||
| 939 | |||
| 940 | ccid3_hc_rx_update_li(sk, seq_loss, win_loss); | ||
| 941 | } | ||
| 942 | |||
| 943 | static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) | ||
| 944 | { | ||
| 945 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 946 | struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 947 | const struct dccp_options_received *opt_recv; | ||
| 948 | struct dccp_rx_hist_entry *packet; | ||
| 949 | struct timeval now; | ||
| 950 | u8 win_count; | ||
| 951 | u32 p_prev; | ||
| 952 | int ins; | ||
| 953 | |||
| 954 | if (hcrx == NULL) | ||
| 955 | return; | ||
| 956 | |||
| 957 | BUG_ON(!(hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA || | ||
| 958 | hcrx->ccid3hcrx_state == TFRC_RSTATE_DATA)); | ||
| 959 | |||
| 960 | opt_recv = &dp->dccps_options_received; | ||
| 961 | |||
| 962 | switch (DCCP_SKB_CB(skb)->dccpd_type) { | ||
| 963 | case DCCP_PKT_ACK: | ||
| 964 | if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) | ||
| 965 | return; | ||
| 966 | case DCCP_PKT_DATAACK: | ||
| 967 | if (opt_recv->dccpor_timestamp_echo == 0) | ||
| 968 | break; | ||
| 969 | p_prev = hcrx->ccid3hcrx_rtt; | ||
| 970 | do_gettimeofday(&now); | ||
| 971 | hcrx->ccid3hcrx_rtt = timeval_usecs(&now) - | ||
| 972 | (opt_recv->dccpor_timestamp_echo - | ||
| 973 | opt_recv->dccpor_elapsed_time) * 10; | ||
| 974 | if (p_prev != hcrx->ccid3hcrx_rtt) | ||
| 975 | ccid3_pr_debug("%s, New RTT=%luus, elapsed time=%u\n", | ||
| 976 | dccp_role(sk), hcrx->ccid3hcrx_rtt, | ||
| 977 | opt_recv->dccpor_elapsed_time); | ||
| 978 | break; | ||
| 979 | case DCCP_PKT_DATA: | ||
| 980 | break; | ||
| 981 | default: | ||
| 982 | ccid3_pr_debug("%s, sk=%p, not DATA/DATAACK/ACK packet(%s)\n", | ||
| 983 | dccp_role(sk), sk, | ||
| 984 | dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type)); | ||
| 985 | return; | ||
| 986 | } | ||
| 987 | |||
| 988 | packet = dccp_rx_hist_entry_new(ccid3_rx_hist, opt_recv->dccpor_ndp, | ||
| 989 | skb, SLAB_ATOMIC); | ||
| 990 | if (packet == NULL) { | ||
| 991 | ccid3_pr_debug("%s, sk=%p, Not enough mem to add rx packet " | ||
| 992 | "to history (consider it lost)!", | ||
| 993 | dccp_role(sk), sk); | ||
| 994 | return; | ||
| 995 | } | ||
| 996 | |||
| 997 | win_count = packet->dccphrx_ccval; | ||
| 998 | |||
| 999 | ins = dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist, | ||
| 1000 | &hcrx->ccid3hcrx_li_hist, packet); | ||
| 1001 | |||
| 1002 | if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK) | ||
| 1003 | return; | ||
| 1004 | |||
| 1005 | switch (hcrx->ccid3hcrx_state) { | ||
| 1006 | case TFRC_RSTATE_NO_DATA: | ||
| 1007 | ccid3_pr_debug("%s, sk=%p(%s), skb=%p, sending initial " | ||
| 1008 | "feedback\n", | ||
| 1009 | dccp_role(sk), sk, | ||
| 1010 | dccp_state_name(sk->sk_state), skb); | ||
| 1011 | ccid3_hc_rx_send_feedback(sk); | ||
| 1012 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); | ||
| 1013 | return; | ||
| 1014 | case TFRC_RSTATE_DATA: | ||
| 1015 | hcrx->ccid3hcrx_bytes_recv += skb->len - | ||
| 1016 | dccp_hdr(skb)->dccph_doff * 4; | ||
| 1017 | if (ins != 0) | ||
| 1018 | break; | ||
| 1019 | |||
| 1020 | do_gettimeofday(&now); | ||
| 1021 | if (timeval_delta(&now, &hcrx->ccid3hcrx_tstamp_last_ack) >= | ||
| 1022 | hcrx->ccid3hcrx_rtt) { | ||
| 1023 | hcrx->ccid3hcrx_tstamp_last_ack = now; | ||
| 1024 | ccid3_hc_rx_send_feedback(sk); | ||
| 1025 | } | ||
| 1026 | return; | ||
| 1027 | default: | ||
| 1028 | printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", | ||
| 1029 | __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state); | ||
| 1030 | dump_stack(); | ||
| 1031 | return; | ||
| 1032 | } | ||
| 1033 | |||
| 1034 | /* Dealing with packet loss */ | ||
| 1035 | ccid3_pr_debug("%s, sk=%p(%s), data loss! Reacting...\n", | ||
| 1036 | dccp_role(sk), sk, dccp_state_name(sk->sk_state)); | ||
| 1037 | |||
| 1038 | ccid3_hc_rx_detect_loss(sk); | ||
| 1039 | p_prev = hcrx->ccid3hcrx_p; | ||
| 1040 | |||
| 1041 | /* Calculate loss event rate */ | ||
| 1042 | if (!list_empty(&hcrx->ccid3hcrx_li_hist)) | ||
| 1043 | /* Scaling up by 1000000 as fixed decimal */ | ||
| 1044 | hcrx->ccid3hcrx_p = 1000000 / dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist); | ||
| 1045 | |||
| 1046 | if (hcrx->ccid3hcrx_p > p_prev) { | ||
| 1047 | ccid3_hc_rx_send_feedback(sk); | ||
| 1048 | return; | ||
| 1049 | } | ||
| 1050 | } | ||
| 1051 | |||
| 1052 | static int ccid3_hc_rx_init(struct sock *sk) | ||
| 1053 | { | ||
| 1054 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 1055 | struct ccid3_hc_rx_sock *hcrx; | ||
| 1056 | |||
| 1057 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | ||
| 1058 | |||
| 1059 | hcrx = dp->dccps_hc_rx_ccid_private = kmalloc(sizeof(*hcrx), | ||
| 1060 | gfp_any()); | ||
| 1061 | if (hcrx == NULL) | ||
| 1062 | return -ENOMEM; | ||
| 1063 | |||
| 1064 | memset(hcrx, 0, sizeof(*hcrx)); | ||
| 1065 | |||
| 1066 | if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE && | ||
| 1067 | dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE) | ||
| 1068 | hcrx->ccid3hcrx_s = dp->dccps_packet_size; | ||
| 1069 | else | ||
| 1070 | hcrx->ccid3hcrx_s = TFRC_STD_PACKET_SIZE; | ||
| 1071 | |||
| 1072 | hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA; | ||
| 1073 | INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist); | ||
| 1074 | INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist); | ||
| 1075 | /* | ||
| 1076 | * XXX this seems to be paranoid, need to think more about this, for | ||
| 1077 | * now start with something different than zero. -acme | ||
| 1078 | */ | ||
| 1079 | hcrx->ccid3hcrx_rtt = USEC_PER_SEC / 5; | ||
| 1080 | return 0; | ||
| 1081 | } | ||
| 1082 | |||
| 1083 | static void ccid3_hc_rx_exit(struct sock *sk) | ||
| 1084 | { | ||
| 1085 | struct dccp_sock *dp = dccp_sk(sk); | ||
| 1086 | struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 1087 | |||
| 1088 | ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); | ||
| 1089 | |||
| 1090 | if (hcrx == NULL) | ||
| 1091 | return; | ||
| 1092 | |||
| 1093 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM); | ||
| 1094 | |||
| 1095 | /* Empty packet history */ | ||
| 1096 | dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist); | ||
| 1097 | |||
| 1098 | /* Empty loss interval history */ | ||
| 1099 | dccp_li_hist_purge(ccid3_li_hist, &hcrx->ccid3hcrx_li_hist); | ||
| 1100 | |||
| 1101 | kfree(dp->dccps_hc_rx_ccid_private); | ||
| 1102 | dp->dccps_hc_rx_ccid_private = NULL; | ||
| 1103 | } | ||
| 1104 | |||
| 1105 | static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) | ||
| 1106 | { | ||
| 1107 | const struct dccp_sock *dp = dccp_sk(sk); | ||
| 1108 | const struct ccid3_hc_rx_sock *hcrx = dp->dccps_hc_rx_ccid_private; | ||
| 1109 | |||
| 1110 | if (hcrx == NULL) | ||
| 1111 | return; | ||
| 1112 | |||
| 1113 | info->tcpi_ca_state = hcrx->ccid3hcrx_state; | ||
| 1114 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; | ||
| 1115 | info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt; | ||
| 1116 | } | ||
| 1117 | |||
| 1118 | static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) | ||
| 1119 | { | ||
| 1120 | const struct dccp_sock *dp = dccp_sk(sk); | ||
| 1121 | const struct ccid3_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; | ||
| 1122 | |||
| 1123 | if (hctx == NULL) | ||
| 1124 | return; | ||
| 1125 | |||
| 1126 | info->tcpi_rto = hctx->ccid3hctx_t_rto; | ||
| 1127 | info->tcpi_rtt = hctx->ccid3hctx_rtt; | ||
| 1128 | } | ||
| 1129 | |||
| 1130 | static struct ccid ccid3 = { | ||
| 1131 | .ccid_id = 3, | ||
| 1132 | .ccid_name = "ccid3", | ||
| 1133 | .ccid_owner = THIS_MODULE, | ||
| 1134 | .ccid_init = ccid3_init, | ||
| 1135 | .ccid_exit = ccid3_exit, | ||
| 1136 | .ccid_hc_tx_init = ccid3_hc_tx_init, | ||
| 1137 | .ccid_hc_tx_exit = ccid3_hc_tx_exit, | ||
| 1138 | .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, | ||
| 1139 | .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, | ||
| 1140 | .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, | ||
| 1141 | .ccid_hc_tx_insert_options = ccid3_hc_tx_insert_options, | ||
| 1142 | .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, | ||
| 1143 | .ccid_hc_rx_init = ccid3_hc_rx_init, | ||
| 1144 | .ccid_hc_rx_exit = ccid3_hc_rx_exit, | ||
| 1145 | .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, | ||
| 1146 | .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, | ||
| 1147 | .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, | ||
| 1148 | .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, | ||
| 1149 | }; | ||
| 1150 | |||
| 1151 | module_param(ccid3_debug, int, 0444); | ||
| 1152 | MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); | ||
| 1153 | |||
| 1154 | static __init int ccid3_module_init(void) | ||
| 1155 | { | ||
| 1156 | int rc = -ENOBUFS; | ||
| 1157 | |||
| 1158 | ccid3_rx_hist = dccp_rx_hist_new("ccid3"); | ||
| 1159 | if (ccid3_rx_hist == NULL) | ||
| 1160 | goto out; | ||
| 1161 | |||
| 1162 | ccid3_tx_hist = dccp_tx_hist_new("ccid3"); | ||
| 1163 | if (ccid3_tx_hist == NULL) | ||
| 1164 | goto out_free_rx; | ||
| 1165 | |||
| 1166 | ccid3_li_hist = dccp_li_hist_new("ccid3"); | ||
| 1167 | if (ccid3_li_hist == NULL) | ||
| 1168 | goto out_free_tx; | ||
| 1169 | |||
| 1170 | rc = ccid_register(&ccid3); | ||
| 1171 | if (rc != 0) | ||
| 1172 | goto out_free_loss_interval_history; | ||
| 1173 | out: | ||
| 1174 | return rc; | ||
| 1175 | |||
| 1176 | out_free_loss_interval_history: | ||
| 1177 | dccp_li_hist_delete(ccid3_li_hist); | ||
| 1178 | ccid3_li_hist = NULL; | ||
| 1179 | out_free_tx: | ||
| 1180 | dccp_tx_hist_delete(ccid3_tx_hist); | ||
| 1181 | ccid3_tx_hist = NULL; | ||
| 1182 | out_free_rx: | ||
| 1183 | dccp_rx_hist_delete(ccid3_rx_hist); | ||
| 1184 | ccid3_rx_hist = NULL; | ||
| 1185 | goto out; | ||
| 1186 | } | ||
| 1187 | module_init(ccid3_module_init); | ||
| 1188 | |||
| 1189 | static __exit void ccid3_module_exit(void) | ||
| 1190 | { | ||
| 1191 | #ifdef CONFIG_IP_DCCP_UNLOAD_HACK | ||
| 1192 | /* | ||
| 1193 | * Hack to use while developing, so that we get rid of the control | ||
| 1194 | * sock, that is what keeps a refcount on dccp.ko -acme | ||
| 1195 | */ | ||
| 1196 | extern void dccp_ctl_sock_exit(void); | ||
| 1197 | |||
| 1198 | dccp_ctl_sock_exit(); | ||
| 1199 | #endif | ||
| 1200 | ccid_unregister(&ccid3); | ||
| 1201 | |||
| 1202 | if (ccid3_tx_hist != NULL) { | ||
| 1203 | dccp_tx_hist_delete(ccid3_tx_hist); | ||
| 1204 | ccid3_tx_hist = NULL; | ||
| 1205 | } | ||
| 1206 | if (ccid3_rx_hist != NULL) { | ||
| 1207 | dccp_rx_hist_delete(ccid3_rx_hist); | ||
| 1208 | ccid3_rx_hist = NULL; | ||
| 1209 | } | ||
| 1210 | if (ccid3_li_hist != NULL) { | ||
| 1211 | dccp_li_hist_delete(ccid3_li_hist); | ||
| 1212 | ccid3_li_hist = NULL; | ||
| 1213 | } | ||
| 1214 | } | ||
| 1215 | module_exit(ccid3_module_exit); | ||
| 1216 | |||
| 1217 | MODULE_AUTHOR("Ian McDonald <iam4@cs.waikato.ac.nz>, " | ||
| 1218 | "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); | ||
| 1219 | MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); | ||
| 1220 | MODULE_LICENSE("GPL"); | ||
| 1221 | MODULE_ALIAS("net-dccp-ccid-3"); | ||
