17c657876SArnaldo Carvalho de Melo /* 27c657876SArnaldo Carvalho de Melo * net/dccp/ccids/ccid3.c 37c657876SArnaldo Carvalho de Melo * 4954c2db8SGerrit Renker * Copyright (c) 2007 The University of Aberdeen, Scotland, UK 5b2f41ff4SIan McDonald * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. 6b2f41ff4SIan McDonald * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz> 77c657876SArnaldo Carvalho de Melo * 87c657876SArnaldo Carvalho de Melo * An implementation of the DCCP protocol 97c657876SArnaldo Carvalho de Melo * 107c657876SArnaldo Carvalho de Melo * This code has been developed by the University of Waikato WAND 117c657876SArnaldo Carvalho de Melo * research group. For further information please see http://www.wand.net.nz/ 127c657876SArnaldo Carvalho de Melo * 137c657876SArnaldo Carvalho de Melo * This code also uses code from Lulea University, rereleased as GPL by its 147c657876SArnaldo Carvalho de Melo * authors: 157c657876SArnaldo Carvalho de Melo * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon 167c657876SArnaldo Carvalho de Melo * 177c657876SArnaldo Carvalho de Melo * Changes to meet Linux coding standards, to make it meet latest ccid3 draft 187c657876SArnaldo Carvalho de Melo * and to make it work as a loadable module in the DCCP stack written by 197c657876SArnaldo Carvalho de Melo * Arnaldo Carvalho de Melo <acme@conectiva.com.br>. 207c657876SArnaldo Carvalho de Melo * 217c657876SArnaldo Carvalho de Melo * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> 227c657876SArnaldo Carvalho de Melo * 237c657876SArnaldo Carvalho de Melo * This program is free software; you can redistribute it and/or modify 247c657876SArnaldo Carvalho de Melo * it under the terms of the GNU General Public License as published by 257c657876SArnaldo Carvalho de Melo * the Free Software Foundation; either version 2 of the License, or 267c657876SArnaldo Carvalho de Melo * (at your option) any later version. 277c657876SArnaldo Carvalho de Melo * 287c657876SArnaldo Carvalho de Melo * This program is distributed in the hope that it will be useful, 297c657876SArnaldo Carvalho de Melo * but WITHOUT ANY WARRANTY; without even the implied warranty of 307c657876SArnaldo Carvalho de Melo * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 317c657876SArnaldo Carvalho de Melo * GNU General Public License for more details. 327c657876SArnaldo Carvalho de Melo * 337c657876SArnaldo Carvalho de Melo * You should have received a copy of the GNU General Public License 347c657876SArnaldo Carvalho de Melo * along with this program; if not, write to the Free Software 357c657876SArnaldo Carvalho de Melo * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 367c657876SArnaldo Carvalho de Melo */ 377c657876SArnaldo Carvalho de Melo #include "../dccp.h" 387c657876SArnaldo Carvalho de Melo #include "ccid3.h" 397c657876SArnaldo Carvalho de Melo 4076fd1e87SGerrit Renker #include <asm/unaligned.h> 4176fd1e87SGerrit Renker 4256724aa4SGerrit Renker #ifdef CONFIG_IP_DCCP_CCID3_DEBUG 4356724aa4SGerrit Renker static int ccid3_debug; 4456724aa4SGerrit Renker #define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a) 457c657876SArnaldo Carvalho de Melo #else 467c657876SArnaldo Carvalho de Melo #define ccid3_pr_debug(format, a...) 477c657876SArnaldo Carvalho de Melo #endif 487c657876SArnaldo Carvalho de Melo 499bf17475SGerrit Renker /* 509bf17475SGerrit Renker * Transmitter Half-Connection Routines 519bf17475SGerrit Renker */ 5256724aa4SGerrit Renker #ifdef CONFIG_IP_DCCP_CCID3_DEBUG 537c657876SArnaldo Carvalho de Melo static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) 547c657876SArnaldo Carvalho de Melo { 557c657876SArnaldo Carvalho de Melo static char *ccid3_state_names[] = { 567c657876SArnaldo Carvalho de Melo [TFRC_SSTATE_NO_SENT] = "NO_SENT", 577c657876SArnaldo Carvalho de Melo [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", 587c657876SArnaldo Carvalho de Melo [TFRC_SSTATE_FBACK] = "FBACK", 597c657876SArnaldo Carvalho de Melo [TFRC_SSTATE_TERM] = "TERM", 607c657876SArnaldo Carvalho de Melo }; 617c657876SArnaldo Carvalho de Melo 627c657876SArnaldo Carvalho de Melo return ccid3_state_names[state]; 637c657876SArnaldo Carvalho de Melo } 647c657876SArnaldo Carvalho de Melo #endif 657c657876SArnaldo Carvalho de Melo 66c25a18baSArnaldo Carvalho de Melo static void ccid3_hc_tx_set_state(struct sock *sk, 671f2333aeSArnaldo Carvalho de Melo enum ccid3_hc_tx_states state) 687c657876SArnaldo Carvalho de Melo { 6959725dc2SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 70842d1ef1SGerrit Renker enum ccid3_hc_tx_states oldstate = hctx->state; 717c657876SArnaldo Carvalho de Melo 727c657876SArnaldo Carvalho de Melo ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", 731f2333aeSArnaldo Carvalho de Melo dccp_role(sk), sk, ccid3_tx_state_name(oldstate), 741f2333aeSArnaldo Carvalho de Melo ccid3_tx_state_name(state)); 757c657876SArnaldo Carvalho de Melo WARN_ON(state == oldstate); 76842d1ef1SGerrit Renker hctx->state = state; 777c657876SArnaldo Carvalho de Melo } 787c657876SArnaldo Carvalho de Melo 7917893bc1SGerrit Renker /* 806c08b2cfSGerrit Renker * Compute the initial sending rate X_init in the manner of RFC 3390: 816c08b2cfSGerrit Renker * 826c08b2cfSGerrit Renker * X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT 836c08b2cfSGerrit Renker * 846c08b2cfSGerrit Renker * Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis 856c08b2cfSGerrit Renker * (rev-02) clarifies the use of RFC 3390 with regard to the above formula. 86a21f9f96SGerrit Renker * For consistency with other parts of the code, X_init is scaled by 2^6. 87a21f9f96SGerrit Renker */ 88a21f9f96SGerrit Renker static inline u64 rfc3390_initial_rate(struct sock *sk) 89a21f9f96SGerrit Renker { 906c08b2cfSGerrit Renker const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 91842d1ef1SGerrit Renker const __u32 w_init = clamp_t(__u32, 4380U, 2 * hctx->s, 4 * hctx->s); 92a21f9f96SGerrit Renker 93842d1ef1SGerrit Renker return scaled_div(w_init << 6, hctx->rtt); 94a21f9f96SGerrit Renker } 95a21f9f96SGerrit Renker 96a21f9f96SGerrit Renker /* 971266adeeSGerrit Renker * Recalculate t_ipi and delta (should be called whenever X changes) 9817893bc1SGerrit Renker */ 99c4e18dadSIlpo Järvinen static void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx) 1007c657876SArnaldo Carvalho de Melo { 1011a21e49aSGerrit Renker /* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */ 102842d1ef1SGerrit Renker hctx->t_ipi = scaled_div32(((u64)hctx->s) << 6, hctx->x); 10317893bc1SGerrit Renker 1047c657876SArnaldo Carvalho de Melo /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ 105842d1ef1SGerrit Renker hctx->delta = min_t(u32, hctx->t_ipi / 2, TFRC_OPSYS_HALF_TIME_GRAN); 1068699be7dSIan McDonald 107842d1ef1SGerrit Renker ccid3_pr_debug("t_ipi=%u, delta=%u, s=%u, X=%u\n", hctx->t_ipi, 108842d1ef1SGerrit Renker hctx->delta, hctx->s, (unsigned)(hctx->x >> 6)); 1097c657876SArnaldo Carvalho de Melo } 110aa97efd9SGerrit Renker 111a5358fdcSGerrit Renker static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hctx, ktime_t now) 112a5358fdcSGerrit Renker { 113842d1ef1SGerrit Renker u32 delta = ktime_us_delta(now, hctx->t_last_win_count); 114a5358fdcSGerrit Renker 115842d1ef1SGerrit Renker return delta / hctx->rtt; 116a5358fdcSGerrit Renker } 117a5358fdcSGerrit Renker 118aa97efd9SGerrit Renker /** 119aa97efd9SGerrit Renker * ccid3_hc_tx_update_x - Update allowed sending rate X 120aa97efd9SGerrit Renker * @stamp: most recent time if available - can be left NULL. 121aa97efd9SGerrit Renker * This function tracks draft rfc3448bis, check there for latest details. 1225c3fbb6aSGerrit Renker * 1231a21e49aSGerrit Renker * Note: X and X_recv are both stored in units of 64 * bytes/second, to support 1241a21e49aSGerrit Renker * fine-grained resolution of sending rates. This requires scaling by 2^6 1251a21e49aSGerrit Renker * throughout the code. Only X_calc is unscaled (in bytes/second). 1261a21e49aSGerrit Renker * 1277c657876SArnaldo Carvalho de Melo */ 128aa97efd9SGerrit Renker static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp) 1297c657876SArnaldo Carvalho de Melo { 13059725dc2SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 131842d1ef1SGerrit Renker u64 min_rate = 2 * hctx->x_recv; 132842d1ef1SGerrit Renker const u64 old_x = hctx->x; 133aa97efd9SGerrit Renker ktime_t now = stamp ? *stamp : ktime_get_real(); 1347c657876SArnaldo Carvalho de Melo 1350c150efbSGerrit Renker /* 1360c150efbSGerrit Renker * Handle IDLE periods: do not reduce below RFC3390 initial sending rate 137a5358fdcSGerrit Renker * when idling [RFC 4342, 5.1]. Definition of idling is from rfc3448bis: 138a5358fdcSGerrit Renker * a sender is idle if it has not sent anything over a 2-RTT-period. 1390c150efbSGerrit Renker * For consistency with X and X_recv, min_rate is also scaled by 2^6. 1400c150efbSGerrit Renker */ 141a5358fdcSGerrit Renker if (ccid3_hc_tx_idle_rtt(hctx, now) >= 2) { 1420c150efbSGerrit Renker min_rate = rfc3390_initial_rate(sk); 143842d1ef1SGerrit Renker min_rate = max(min_rate, 2 * hctx->x_recv); 1440c150efbSGerrit Renker } 1450c150efbSGerrit Renker 146842d1ef1SGerrit Renker if (hctx->p > 0) { 1471a21e49aSGerrit Renker 148842d1ef1SGerrit Renker hctx->x = min(((u64)hctx->x_calc) << 6, min_rate); 149842d1ef1SGerrit Renker hctx->x = max(hctx->x, (((u64)hctx->s) << 6) / TFRC_T_MBI); 150b6ee3d4aSArnaldo Carvalho de Melo 151842d1ef1SGerrit Renker } else if (ktime_us_delta(now, hctx->t_ld) - (s64)hctx->rtt >= 0) { 1521a21e49aSGerrit Renker 153842d1ef1SGerrit Renker hctx->x = min(2 * hctx->x, min_rate); 154842d1ef1SGerrit Renker hctx->x = max(hctx->x, 155842d1ef1SGerrit Renker scaled_div(((u64)hctx->s) << 6, hctx->rtt)); 156842d1ef1SGerrit Renker hctx->t_ld = now; 157ac198ea8SArnaldo Carvalho de Melo } 158a79ef76fSGerrit Renker 159842d1ef1SGerrit Renker if (hctx->x != old_x) { 1601761f7d7SGerrit Renker ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, " 1611761f7d7SGerrit Renker "X_recv=%u\n", (unsigned)(old_x >> 6), 162842d1ef1SGerrit Renker (unsigned)(hctx->x >> 6), hctx->x_calc, 163842d1ef1SGerrit Renker (unsigned)(hctx->x_recv >> 6)); 1648699be7dSIan McDonald 1651266adeeSGerrit Renker ccid3_update_send_interval(hctx); 1667c657876SArnaldo Carvalho de Melo } 1678699be7dSIan McDonald } 1687c657876SArnaldo Carvalho de Melo 16978ad713dSGerrit Renker /* 17078ad713dSGerrit Renker * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1) 17178ad713dSGerrit Renker * @len: DCCP packet payload size in bytes 17278ad713dSGerrit Renker */ 17378ad713dSGerrit Renker static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len) 17478ad713dSGerrit Renker { 175842d1ef1SGerrit Renker const u16 old_s = hctx->s; 1761266adeeSGerrit Renker 177842d1ef1SGerrit Renker hctx->s = tfrc_ewma(hctx->s, len, 9); 1781266adeeSGerrit Renker 179842d1ef1SGerrit Renker if (hctx->s != old_s) 1801266adeeSGerrit Renker ccid3_update_send_interval(hctx); 18178ad713dSGerrit Renker } 18278ad713dSGerrit Renker 1839f8681dbSGerrit Renker /* 1849f8681dbSGerrit Renker * Update Window Counter using the algorithm from [RFC 4342, 8.1]. 185825de27dSGerrit Renker * As elsewhere, RTT > 0 is assumed by using dccp_sample_rtt(). 1869f8681dbSGerrit Renker */ 1879f8681dbSGerrit Renker static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hctx, 1888132da4dSGerrit Renker ktime_t now) 1899f8681dbSGerrit Renker { 190842d1ef1SGerrit Renker u32 delta = ktime_us_delta(now, hctx->t_last_win_count), 191842d1ef1SGerrit Renker quarter_rtts = (4 * delta) / hctx->rtt; 1929f8681dbSGerrit Renker 1939f8681dbSGerrit Renker if (quarter_rtts > 0) { 194842d1ef1SGerrit Renker hctx->t_last_win_count = now; 195842d1ef1SGerrit Renker hctx->last_win_count += min(quarter_rtts, 5U); 196842d1ef1SGerrit Renker hctx->last_win_count &= 0xF; /* mod 16 */ 1979f8681dbSGerrit Renker } 1989f8681dbSGerrit Renker } 1999f8681dbSGerrit Renker 2007c657876SArnaldo Carvalho de Melo static void ccid3_hc_tx_no_feedback_timer(unsigned long data) 2017c657876SArnaldo Carvalho de Melo { 2027c657876SArnaldo Carvalho de Melo struct sock *sk = (struct sock *)data; 20359725dc2SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 2042a1fda6fSGerrit Renker unsigned long t_nfb = USEC_PER_SEC / 5; 2057c657876SArnaldo Carvalho de Melo 2067c657876SArnaldo Carvalho de Melo bh_lock_sock(sk); 2077c657876SArnaldo Carvalho de Melo if (sock_owned_by_user(sk)) { 2087c657876SArnaldo Carvalho de Melo /* Try again later. */ 2097c657876SArnaldo Carvalho de Melo /* XXX: set some sensible MIB */ 21048e03eeeSGerrit Renker goto restart_timer; 2117c657876SArnaldo Carvalho de Melo } 2127c657876SArnaldo Carvalho de Melo 213a9672411SGerrit Renker ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk, 214842d1ef1SGerrit Renker ccid3_tx_state_name(hctx->state)); 2157c657876SArnaldo Carvalho de Melo 216842d1ef1SGerrit Renker if (hctx->state == TFRC_SSTATE_FBACK) 21752515e77SGerrit Renker ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); 218842d1ef1SGerrit Renker else if (hctx->state != TFRC_SSTATE_NO_FBACK) 21952515e77SGerrit Renker goto out; 22052515e77SGerrit Renker 22152515e77SGerrit Renker /* 22252515e77SGerrit Renker * Determine new allowed sending rate X as per draft rfc3448bis-00, 4.4 223842d1ef1SGerrit Renker * RTO is 0 if and only if no feedback has been received yet. 22452515e77SGerrit Renker */ 225842d1ef1SGerrit Renker if (hctx->t_rto == 0 || hctx->p == 0) { 22652515e77SGerrit Renker 22752515e77SGerrit Renker /* halve send rate directly */ 228842d1ef1SGerrit Renker hctx->x = max(hctx->x / 2, (((u64)hctx->s) << 6) / TFRC_T_MBI); 2291266adeeSGerrit Renker ccid3_update_send_interval(hctx); 23052515e77SGerrit Renker } else { 2311f2333aeSArnaldo Carvalho de Melo /* 23252515e77SGerrit Renker * Modify the cached value of X_recv 233ff586298SGerrit Renker * 23452515e77SGerrit Renker * If (X_calc > 2 * X_recv) 2357c657876SArnaldo Carvalho de Melo * X_recv = max(X_recv / 2, s / (2 * t_mbi)); 2367c657876SArnaldo Carvalho de Melo * Else 2377c657876SArnaldo Carvalho de Melo * X_recv = X_calc / 4; 2381a21e49aSGerrit Renker * 2391a21e49aSGerrit Renker * Note that X_recv is scaled by 2^6 while X_calc is not 2407c657876SArnaldo Carvalho de Melo */ 241842d1ef1SGerrit Renker BUG_ON(hctx->p && !hctx->x_calc); 2427c657876SArnaldo Carvalho de Melo 243842d1ef1SGerrit Renker if (hctx->x_calc > (hctx->x_recv >> 5)) 244842d1ef1SGerrit Renker hctx->x_recv = 245842d1ef1SGerrit Renker max(hctx->x_recv / 2, 246842d1ef1SGerrit Renker (((__u64)hctx->s) << 6) / (2 * TFRC_T_MBI)); 24752515e77SGerrit Renker else { 248842d1ef1SGerrit Renker hctx->x_recv = hctx->x_calc; 249842d1ef1SGerrit Renker hctx->x_recv <<= 4; 2509e8efc82SGerrit Renker } 251aa97efd9SGerrit Renker ccid3_hc_tx_update_x(sk, NULL); 25252515e77SGerrit Renker } 25352515e77SGerrit Renker ccid3_pr_debug("Reduced X to %llu/64 bytes/sec\n", 254842d1ef1SGerrit Renker (unsigned long long)hctx->x); 25552515e77SGerrit Renker 2566b5e633aSArnaldo Carvalho de Melo /* 25752515e77SGerrit Renker * Set new timeout for the nofeedback timer. 2588a508ac2SGerrit Renker * See comments in packet_recv() regarding the value of t_RTO. 2596b5e633aSArnaldo Carvalho de Melo */ 260842d1ef1SGerrit Renker if (unlikely(hctx->t_rto == 0)) /* no feedback received yet */ 26152515e77SGerrit Renker t_nfb = TFRC_INITIAL_TIMEOUT; 26252515e77SGerrit Renker else 263842d1ef1SGerrit Renker t_nfb = max(hctx->t_rto, 2 * hctx->t_ipi); 2647c657876SArnaldo Carvalho de Melo 26548e03eeeSGerrit Renker restart_timer: 266842d1ef1SGerrit Renker sk_reset_timer(sk, &hctx->no_feedback_timer, 2672a1fda6fSGerrit Renker jiffies + usecs_to_jiffies(t_nfb)); 2687c657876SArnaldo Carvalho de Melo out: 2697c657876SArnaldo Carvalho de Melo bh_unlock_sock(sk); 2707c657876SArnaldo Carvalho de Melo sock_put(sk); 2717c657876SArnaldo Carvalho de Melo } 2727c657876SArnaldo Carvalho de Melo 2737da7f456SGerrit Renker /* 2747da7f456SGerrit Renker * returns 2757da7f456SGerrit Renker * > 0: delay (in msecs) that should pass before actually sending 2767da7f456SGerrit Renker * = 0: can send immediately 2777da7f456SGerrit Renker * < 0: error condition; do not send packet 2787da7f456SGerrit Renker */ 2796b57c93dSGerrit Renker static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) 2807c657876SArnaldo Carvalho de Melo { 2817c657876SArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 28259725dc2SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 2838132da4dSGerrit Renker ktime_t now = ktime_get_real(); 2848132da4dSGerrit Renker s64 delay; 2857c657876SArnaldo Carvalho de Melo 2867c657876SArnaldo Carvalho de Melo /* 287da335bafSGerrit Renker * This function is called only for Data and DataAck packets. Sending 288da335bafSGerrit Renker * zero-sized Data(Ack)s is theoretically possible, but for congestion 289da335bafSGerrit Renker * control this case is pathological - ignore it. 2907c657876SArnaldo Carvalho de Melo */ 2916b57c93dSGerrit Renker if (unlikely(skb->len == 0)) 292da335bafSGerrit Renker return -EBADMSG; 2937c657876SArnaldo Carvalho de Melo 294842d1ef1SGerrit Renker switch (hctx->state) { 2957c657876SArnaldo Carvalho de Melo case TFRC_SSTATE_NO_SENT: 296842d1ef1SGerrit Renker sk_reset_timer(sk, &hctx->no_feedback_timer, (jiffies + 2978109b02bSArnaldo Carvalho de Melo usecs_to_jiffies(TFRC_INITIAL_TIMEOUT))); 298842d1ef1SGerrit Renker hctx->last_win_count = 0; 299842d1ef1SGerrit Renker hctx->t_last_win_count = now; 30090feeb95SGerrit Renker 30190feeb95SGerrit Renker /* Set t_0 for initial packet */ 302842d1ef1SGerrit Renker hctx->t_nom = now; 30330833ffeSGerrit Renker 304842d1ef1SGerrit Renker hctx->s = skb->len; 30530833ffeSGerrit Renker 30630833ffeSGerrit Renker /* 30730833ffeSGerrit Renker * Use initial RTT sample when available: recommended by erratum 30830833ffeSGerrit Renker * to RFC 4342. This implements the initialisation procedure of 30930833ffeSGerrit Renker * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6. 31030833ffeSGerrit Renker */ 31130833ffeSGerrit Renker if (dp->dccps_syn_rtt) { 31230833ffeSGerrit Renker ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt); 313842d1ef1SGerrit Renker hctx->rtt = dp->dccps_syn_rtt; 314842d1ef1SGerrit Renker hctx->x = rfc3390_initial_rate(sk); 315842d1ef1SGerrit Renker hctx->t_ld = now; 31630833ffeSGerrit Renker } else { 3173294f202SGerrit Renker /* 3183294f202SGerrit Renker * Sender does not have RTT sample: 3193294f202SGerrit Renker * - set fallback RTT (RFC 4340, 3.4) since a RTT value 3203294f202SGerrit Renker * is needed in several parts (e.g. window counter); 3213294f202SGerrit Renker * - set sending rate X_pps = 1pps as per RFC 3448, 4.2. 3223294f202SGerrit Renker */ 323842d1ef1SGerrit Renker hctx->rtt = DCCP_FALLBACK_RTT; 324842d1ef1SGerrit Renker hctx->x = hctx->s; 325842d1ef1SGerrit Renker hctx->x <<= 6; 32630833ffeSGerrit Renker } 32730833ffeSGerrit Renker ccid3_update_send_interval(hctx); 32830833ffeSGerrit Renker 32930833ffeSGerrit Renker ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); 3307c657876SArnaldo Carvalho de Melo break; 3317c657876SArnaldo Carvalho de Melo case TFRC_SSTATE_NO_FBACK: 3327c657876SArnaldo Carvalho de Melo case TFRC_SSTATE_FBACK: 333842d1ef1SGerrit Renker delay = ktime_us_delta(hctx->t_nom, now); 3348699be7dSIan McDonald ccid3_pr_debug("delay=%ld\n", (long)delay); 33591cf5a17SGerrit Renker /* 33691cf5a17SGerrit Renker * Scheduling of packet transmissions [RFC 3448, 4.6] 33791cf5a17SGerrit Renker * 33891cf5a17SGerrit Renker * if (t_now > t_nom - delta) 33991cf5a17SGerrit Renker * // send the packet now 34091cf5a17SGerrit Renker * else 34191cf5a17SGerrit Renker * // send the packet in (t_nom - t_now) milliseconds. 34291cf5a17SGerrit Renker */ 343842d1ef1SGerrit Renker if (delay - (s64)hctx->delta >= 1000) 3448132da4dSGerrit Renker return (u32)delay / 1000L; 3459f8681dbSGerrit Renker 3468132da4dSGerrit Renker ccid3_hc_tx_update_win_count(hctx, now); 3477c657876SArnaldo Carvalho de Melo break; 34859348b19SGerrit Renker case TFRC_SSTATE_TERM: 349a9672411SGerrit Renker DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); 3507da7f456SGerrit Renker return -EINVAL; 3517c657876SArnaldo Carvalho de Melo } 3527c657876SArnaldo Carvalho de Melo 3537da7f456SGerrit Renker /* prepare to send now (add options etc.) */ 354507d37cfSArnaldo Carvalho de Melo dp->dccps_hc_tx_insert_options = 1; 355842d1ef1SGerrit Renker DCCP_SKB_CB(skb)->dccpd_ccval = hctx->last_win_count; 356e312d100SGerrit Renker 357e312d100SGerrit Renker /* set the nominal send time for the next following packet */ 358842d1ef1SGerrit Renker hctx->t_nom = ktime_add_us(hctx->t_nom, hctx->t_ipi); 3597da7f456SGerrit Renker return 0; 3607c657876SArnaldo Carvalho de Melo } 3617c657876SArnaldo Carvalho de Melo 3628109b02bSArnaldo Carvalho de Melo static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, 3638109b02bSArnaldo Carvalho de Melo unsigned int len) 3647c657876SArnaldo Carvalho de Melo { 36559725dc2SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 3667c657876SArnaldo Carvalho de Melo 36778ad713dSGerrit Renker ccid3_hc_tx_update_s(hctx, len); 36878ad713dSGerrit Renker 369842d1ef1SGerrit Renker if (tfrc_tx_hist_add(&hctx->hist, dccp_sk(sk)->dccps_gss)) 370c5a1ae9aSGerrit Renker DCCP_CRIT("packet history - out of memory!"); 3717c657876SArnaldo Carvalho de Melo } 3727c657876SArnaldo Carvalho de Melo 3737c657876SArnaldo Carvalho de Melo static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) 3747c657876SArnaldo Carvalho de Melo { 37559725dc2SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 376842d1ef1SGerrit Renker struct ccid3_options_received *opt_recv = &hctx->options_received; 3770740d49cSArnaldo Carvalho de Melo ktime_t now; 3782a1fda6fSGerrit Renker unsigned long t_nfb; 3797dfee1a9SGerrit Renker u32 pinv, r_sample; 3801f2333aeSArnaldo Carvalho de Melo 3817c657876SArnaldo Carvalho de Melo /* we are only interested in ACKs */ 3827c657876SArnaldo Carvalho de Melo if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || 3837c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) 3847c657876SArnaldo Carvalho de Melo return; 3855bd370a6SGerrit Renker /* ... and only in the established state */ 386842d1ef1SGerrit Renker if (hctx->state != TFRC_SSTATE_FBACK && 387842d1ef1SGerrit Renker hctx->state != TFRC_SSTATE_NO_FBACK) 3885bd370a6SGerrit Renker return; 3897c657876SArnaldo Carvalho de Melo 3909108d5f4SArnaldo Carvalho de Melo now = ktime_get_real(); 3919108d5f4SArnaldo Carvalho de Melo 3925bd370a6SGerrit Renker /* Estimate RTT from history if ACK number is valid */ 393842d1ef1SGerrit Renker r_sample = tfrc_tx_hist_rtt(hctx->hist, 3949108d5f4SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_ack_seq, now); 3959108d5f4SArnaldo Carvalho de Melo if (r_sample == 0) { 396276f2edcSArnaldo Carvalho de Melo DCCP_WARN("%s(%p): %s with bogus ACK-%llu\n", dccp_role(sk), sk, 397276f2edcSArnaldo Carvalho de Melo dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type), 398276f2edcSArnaldo Carvalho de Melo (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq); 3997c657876SArnaldo Carvalho de Melo return; 4007c657876SArnaldo Carvalho de Melo } 4017c657876SArnaldo Carvalho de Melo 4021a21e49aSGerrit Renker /* Update receive rate in units of 64 * bytes/second */ 403842d1ef1SGerrit Renker hctx->x_recv = opt_recv->ccid3or_receive_rate; 404842d1ef1SGerrit Renker hctx->x_recv <<= 6; 4055c3fbb6aSGerrit Renker 4065bd370a6SGerrit Renker /* Update loss event rate (which is scaled by 1e6) */ 4075c3fbb6aSGerrit Renker pinv = opt_recv->ccid3or_loss_event_rate; 40845393a66SGerrit Renker if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */ 409842d1ef1SGerrit Renker hctx->p = 0; 41045393a66SGerrit Renker else /* can not exceed 100% */ 411842d1ef1SGerrit Renker hctx->p = scaled_div(1, pinv); 4125c3fbb6aSGerrit Renker /* 4139108d5f4SArnaldo Carvalho de Melo * Validate new RTT sample and update moving average 4145c3fbb6aSGerrit Renker */ 4159108d5f4SArnaldo Carvalho de Melo r_sample = dccp_sample_rtt(sk, r_sample); 416842d1ef1SGerrit Renker hctx->rtt = tfrc_ewma(hctx->rtt, r_sample, 9); 4171a21e49aSGerrit Renker /* 418d8d1252fSGerrit Renker * Update allowed sending rate X as per draft rfc3448bis-00, 4.2/3 419d8d1252fSGerrit Renker */ 420842d1ef1SGerrit Renker if (hctx->state == TFRC_SSTATE_NO_FBACK) { 421d8d1252fSGerrit Renker ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); 422d8d1252fSGerrit Renker 423842d1ef1SGerrit Renker if (hctx->t_rto == 0) { 424d8d1252fSGerrit Renker /* 425d8d1252fSGerrit Renker * Initial feedback packet: Larger Initial Windows (4.2) 4261a21e49aSGerrit Renker */ 427842d1ef1SGerrit Renker hctx->x = rfc3390_initial_rate(sk); 428842d1ef1SGerrit Renker hctx->t_ld = now; 429a79ef76fSGerrit Renker 4301266adeeSGerrit Renker ccid3_update_send_interval(hctx); 4315c3fbb6aSGerrit Renker 432d8d1252fSGerrit Renker goto done_computing_x; 433842d1ef1SGerrit Renker } else if (hctx->p == 0) { 434d8d1252fSGerrit Renker /* 435d8d1252fSGerrit Renker * First feedback after nofeedback timer expiry (4.3) 436d8d1252fSGerrit Renker */ 437d8d1252fSGerrit Renker goto done_computing_x; 438d8d1252fSGerrit Renker } 439d8d1252fSGerrit Renker } 4405c3fbb6aSGerrit Renker 441ff586298SGerrit Renker /* Update sending rate (step 4 of [RFC 3448, 4.3]) */ 442842d1ef1SGerrit Renker if (hctx->p > 0) 443842d1ef1SGerrit Renker hctx->x_calc = tfrc_calc_x(hctx->s, hctx->rtt, hctx->p); 444aa97efd9SGerrit Renker ccid3_hc_tx_update_x(sk, &now); 4457c657876SArnaldo Carvalho de Melo 446d8d1252fSGerrit Renker done_computing_x: 4477dfee1a9SGerrit Renker ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, " 4488109b02bSArnaldo Carvalho de Melo "p=%u, X_calc=%u, X_recv=%u, X=%u\n", 449842d1ef1SGerrit Renker dccp_role(sk), sk, hctx->rtt, r_sample, 450842d1ef1SGerrit Renker hctx->s, hctx->p, hctx->x_calc, 451842d1ef1SGerrit Renker (unsigned)(hctx->x_recv >> 6), 452842d1ef1SGerrit Renker (unsigned)(hctx->x >> 6)); 4537c657876SArnaldo Carvalho de Melo 4547c657876SArnaldo Carvalho de Melo /* unschedule no feedback timer */ 455842d1ef1SGerrit Renker sk_stop_timer(sk, &hctx->no_feedback_timer); 4567c657876SArnaldo Carvalho de Melo 457c530cfb1SArnaldo Carvalho de Melo /* 4588109b02bSArnaldo Carvalho de Melo * As we have calculated new ipi, delta, t_nom it is possible 4598109b02bSArnaldo Carvalho de Melo * that we now can send a packet, so wake up dccp_wait_for_ccid 460c530cfb1SArnaldo Carvalho de Melo */ 461c530cfb1SArnaldo Carvalho de Melo sk->sk_write_space(sk); 4628c60f3faSArnaldo Carvalho de Melo 4638a508ac2SGerrit Renker /* 4648a508ac2SGerrit Renker * Update timeout interval for the nofeedback timer. 4658a508ac2SGerrit Renker * We use a configuration option to increase the lower bound. 4668109b02bSArnaldo Carvalho de Melo * This can help avoid triggering the nofeedback timer too 4678109b02bSArnaldo Carvalho de Melo * often ('spinning') on LANs with small RTTs. 4688a508ac2SGerrit Renker */ 469842d1ef1SGerrit Renker hctx->t_rto = max_t(u32, 4 * hctx->rtt, (CONFIG_IP_DCCP_CCID3_RTO * 4705bd370a6SGerrit Renker (USEC_PER_SEC / 1000))); 4711f2333aeSArnaldo Carvalho de Melo /* 4721f2333aeSArnaldo Carvalho de Melo * Schedule no feedback timer to expire in 4738a508ac2SGerrit Renker * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) 4741f2333aeSArnaldo Carvalho de Melo */ 475842d1ef1SGerrit Renker t_nfb = max(hctx->t_rto, 2 * hctx->t_ipi); 4767c657876SArnaldo Carvalho de Melo 477a9672411SGerrit Renker ccid3_pr_debug("%s(%p), Scheduled no feedback timer to " 4788109b02bSArnaldo Carvalho de Melo "expire in %lu jiffies (%luus)\n", 479842d1ef1SGerrit Renker dccp_role(sk), sk, usecs_to_jiffies(t_nfb), t_nfb); 4807c657876SArnaldo Carvalho de Melo 481842d1ef1SGerrit Renker sk_reset_timer(sk, &hctx->no_feedback_timer, 4822a1fda6fSGerrit Renker jiffies + usecs_to_jiffies(t_nfb)); 4837c657876SArnaldo Carvalho de Melo } 4847c657876SArnaldo Carvalho de Melo 4857c657876SArnaldo Carvalho de Melo static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, 4861f2333aeSArnaldo Carvalho de Melo unsigned char len, u16 idx, 4871f2333aeSArnaldo Carvalho de Melo unsigned char *value) 4887c657876SArnaldo Carvalho de Melo { 4897c657876SArnaldo Carvalho de Melo int rc = 0; 49059725dc2SArnaldo Carvalho de Melo const struct dccp_sock *dp = dccp_sk(sk); 49159725dc2SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 492842d1ef1SGerrit Renker struct ccid3_options_received *opt_recv = &hctx->options_received; 49376fd1e87SGerrit Renker __be32 opt_val; 4947c657876SArnaldo Carvalho de Melo 4957c657876SArnaldo Carvalho de Melo if (opt_recv->ccid3or_seqno != dp->dccps_gsr) { 4967c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_seqno = dp->dccps_gsr; 4977c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_loss_event_rate = ~0; 4987c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_loss_intervals_idx = 0; 4997c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_loss_intervals_len = 0; 5007c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_receive_rate = 0; 5017c657876SArnaldo Carvalho de Melo } 5027c657876SArnaldo Carvalho de Melo 5037c657876SArnaldo Carvalho de Melo switch (option) { 5047c657876SArnaldo Carvalho de Melo case TFRC_OPT_LOSS_EVENT_RATE: 50559d203f9SArnaldo Carvalho de Melo if (unlikely(len != 4)) { 506a9672411SGerrit Renker DCCP_WARN("%s(%p), invalid len %d " 50759348b19SGerrit Renker "for TFRC_OPT_LOSS_EVENT_RATE\n", 50859348b19SGerrit Renker dccp_role(sk), sk, len); 5097c657876SArnaldo Carvalho de Melo rc = -EINVAL; 5107c657876SArnaldo Carvalho de Melo } else { 51176fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 51276fd1e87SGerrit Renker opt_recv->ccid3or_loss_event_rate = ntohl(opt_val); 513a9672411SGerrit Renker ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n", 5147c657876SArnaldo Carvalho de Melo dccp_role(sk), sk, 5157c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_loss_event_rate); 5167c657876SArnaldo Carvalho de Melo } 5177c657876SArnaldo Carvalho de Melo break; 5187c657876SArnaldo Carvalho de Melo case TFRC_OPT_LOSS_INTERVALS: 5197c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_loss_intervals_idx = idx; 5207c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_loss_intervals_len = len; 521a9672411SGerrit Renker ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n", 5227c657876SArnaldo Carvalho de Melo dccp_role(sk), sk, 5237c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_loss_intervals_idx, 5247c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_loss_intervals_len); 5257c657876SArnaldo Carvalho de Melo break; 5267c657876SArnaldo Carvalho de Melo case TFRC_OPT_RECEIVE_RATE: 52759d203f9SArnaldo Carvalho de Melo if (unlikely(len != 4)) { 528a9672411SGerrit Renker DCCP_WARN("%s(%p), invalid len %d " 52959348b19SGerrit Renker "for TFRC_OPT_RECEIVE_RATE\n", 53059348b19SGerrit Renker dccp_role(sk), sk, len); 5317c657876SArnaldo Carvalho de Melo rc = -EINVAL; 5327c657876SArnaldo Carvalho de Melo } else { 53376fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 53476fd1e87SGerrit Renker opt_recv->ccid3or_receive_rate = ntohl(opt_val); 535a9672411SGerrit Renker ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n", 5367c657876SArnaldo Carvalho de Melo dccp_role(sk), sk, 5377c657876SArnaldo Carvalho de Melo opt_recv->ccid3or_receive_rate); 5387c657876SArnaldo Carvalho de Melo } 5397c657876SArnaldo Carvalho de Melo break; 5407c657876SArnaldo Carvalho de Melo } 5417c657876SArnaldo Carvalho de Melo 5427c657876SArnaldo Carvalho de Melo return rc; 5437c657876SArnaldo Carvalho de Melo } 5447c657876SArnaldo Carvalho de Melo 54591f0ebf7SArnaldo Carvalho de Melo static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk) 5467c657876SArnaldo Carvalho de Melo { 54791f0ebf7SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid); 5487c657876SArnaldo Carvalho de Melo 549842d1ef1SGerrit Renker hctx->state = TFRC_SSTATE_NO_SENT; 550842d1ef1SGerrit Renker hctx->hist = NULL; 551842d1ef1SGerrit Renker setup_timer(&hctx->no_feedback_timer, 552b24b8a24SPavel Emelyanov ccid3_hc_tx_no_feedback_timer, (unsigned long)sk); 5537c657876SArnaldo Carvalho de Melo return 0; 5547c657876SArnaldo Carvalho de Melo } 5557c657876SArnaldo Carvalho de Melo 5567c657876SArnaldo Carvalho de Melo static void ccid3_hc_tx_exit(struct sock *sk) 5577c657876SArnaldo Carvalho de Melo { 55859725dc2SArnaldo Carvalho de Melo struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 5597c657876SArnaldo Carvalho de Melo 5607c657876SArnaldo Carvalho de Melo ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM); 561842d1ef1SGerrit Renker sk_stop_timer(sk, &hctx->no_feedback_timer); 5627c657876SArnaldo Carvalho de Melo 563842d1ef1SGerrit Renker tfrc_tx_hist_purge(&hctx->hist); 5647c657876SArnaldo Carvalho de Melo } 5657c657876SArnaldo Carvalho de Melo 5669bf17475SGerrit Renker static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) 5679bf17475SGerrit Renker { 568b2e317f4SGerrit Renker info->tcpi_rto = ccid3_hc_tx_sk(sk)->t_rto; 569b2e317f4SGerrit Renker info->tcpi_rtt = ccid3_hc_tx_sk(sk)->rtt; 5709bf17475SGerrit Renker } 5719bf17475SGerrit Renker 5729bf17475SGerrit Renker static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, 5739bf17475SGerrit Renker u32 __user *optval, int __user *optlen) 5749bf17475SGerrit Renker { 575b2e317f4SGerrit Renker const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); 576842d1ef1SGerrit Renker struct tfrc_tx_info tfrc; 5779bf17475SGerrit Renker const void *val; 5789bf17475SGerrit Renker 5799bf17475SGerrit Renker switch (optname) { 5809bf17475SGerrit Renker case DCCP_SOCKOPT_CCID_TX_INFO: 581842d1ef1SGerrit Renker if (len < sizeof(tfrc)) 5829bf17475SGerrit Renker return -EINVAL; 583842d1ef1SGerrit Renker tfrc.tfrctx_x = hctx->x; 584842d1ef1SGerrit Renker tfrc.tfrctx_x_recv = hctx->x_recv; 585842d1ef1SGerrit Renker tfrc.tfrctx_x_calc = hctx->x_calc; 586842d1ef1SGerrit Renker tfrc.tfrctx_rtt = hctx->rtt; 587842d1ef1SGerrit Renker tfrc.tfrctx_p = hctx->p; 588842d1ef1SGerrit Renker tfrc.tfrctx_rto = hctx->t_rto; 589842d1ef1SGerrit Renker tfrc.tfrctx_ipi = hctx->t_ipi; 590842d1ef1SGerrit Renker len = sizeof(tfrc); 591842d1ef1SGerrit Renker val = &tfrc; 5929bf17475SGerrit Renker break; 5939bf17475SGerrit Renker default: 5949bf17475SGerrit Renker return -ENOPROTOOPT; 5959bf17475SGerrit Renker } 5969bf17475SGerrit Renker 5979bf17475SGerrit Renker if (put_user(len, optlen) || copy_to_user(optval, val, len)) 5989bf17475SGerrit Renker return -EFAULT; 5999bf17475SGerrit Renker 6009bf17475SGerrit Renker return 0; 6019bf17475SGerrit Renker } 6029bf17475SGerrit Renker 6039bf17475SGerrit Renker /* 6049bf17475SGerrit Renker * Receiver Half-Connection Routines 6059bf17475SGerrit Renker */ 606b84a2189SArnaldo Carvalho de Melo 607b84a2189SArnaldo Carvalho de Melo /* CCID3 feedback types */ 608b84a2189SArnaldo Carvalho de Melo enum ccid3_fback_type { 609b84a2189SArnaldo Carvalho de Melo CCID3_FBACK_NONE = 0, 610b84a2189SArnaldo Carvalho de Melo CCID3_FBACK_INITIAL, 611b84a2189SArnaldo Carvalho de Melo CCID3_FBACK_PERIODIC, 612b84a2189SArnaldo Carvalho de Melo CCID3_FBACK_PARAM_CHANGE 613b84a2189SArnaldo Carvalho de Melo }; 614b84a2189SArnaldo Carvalho de Melo 61556724aa4SGerrit Renker #ifdef CONFIG_IP_DCCP_CCID3_DEBUG 6167c657876SArnaldo Carvalho de Melo static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) 6177c657876SArnaldo Carvalho de Melo { 6187c657876SArnaldo Carvalho de Melo static char *ccid3_rx_state_names[] = { 6197c657876SArnaldo Carvalho de Melo [TFRC_RSTATE_NO_DATA] = "NO_DATA", 6207c657876SArnaldo Carvalho de Melo [TFRC_RSTATE_DATA] = "DATA", 6217c657876SArnaldo Carvalho de Melo [TFRC_RSTATE_TERM] = "TERM", 6227c657876SArnaldo Carvalho de Melo }; 6237c657876SArnaldo Carvalho de Melo 6247c657876SArnaldo Carvalho de Melo return ccid3_rx_state_names[state]; 6257c657876SArnaldo Carvalho de Melo } 6267c657876SArnaldo Carvalho de Melo #endif 6277c657876SArnaldo Carvalho de Melo 628c25a18baSArnaldo Carvalho de Melo static void ccid3_hc_rx_set_state(struct sock *sk, 6291f2333aeSArnaldo Carvalho de Melo enum ccid3_hc_rx_states state) 6307c657876SArnaldo Carvalho de Melo { 63159725dc2SArnaldo Carvalho de Melo struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); 632842d1ef1SGerrit Renker enum ccid3_hc_rx_states oldstate = hcrx->state; 6337c657876SArnaldo Carvalho de Melo 6347c657876SArnaldo Carvalho de Melo ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", 6351f2333aeSArnaldo Carvalho de Melo dccp_role(sk), sk, ccid3_rx_state_name(oldstate), 6361f2333aeSArnaldo Carvalho de Melo ccid3_rx_state_name(state)); 6377c657876SArnaldo Carvalho de Melo WARN_ON(state == oldstate); 638842d1ef1SGerrit Renker hcrx->state = state; 6397c657876SArnaldo Carvalho de Melo } 6407c657876SArnaldo Carvalho de Melo 641b84a2189SArnaldo Carvalho de Melo static void ccid3_hc_rx_send_feedback(struct sock *sk, 642b84a2189SArnaldo Carvalho de Melo const struct sk_buff *skb, 643b84a2189SArnaldo Carvalho de Melo enum ccid3_fback_type fbtype) 6447c657876SArnaldo Carvalho de Melo { 64559725dc2SArnaldo Carvalho de Melo struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); 6467c657876SArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 647e7c23357SArnaldo Carvalho de Melo ktime_t now; 648b84a2189SArnaldo Carvalho de Melo s64 delta = 0; 6497c657876SArnaldo Carvalho de Melo 650842d1ef1SGerrit Renker if (unlikely(hcrx->state == TFRC_RSTATE_TERM)) 651b84a2189SArnaldo Carvalho de Melo return; 652b84a2189SArnaldo Carvalho de Melo 653e7a81c6dSArnaldo Carvalho de Melo now = ktime_get_real(); 654b6ee3d4aSArnaldo Carvalho de Melo 655b84a2189SArnaldo Carvalho de Melo switch (fbtype) { 656b84a2189SArnaldo Carvalho de Melo case CCID3_FBACK_INITIAL: 657842d1ef1SGerrit Renker hcrx->x_recv = 0; 658842d1ef1SGerrit Renker hcrx->p_inverse = ~0U; /* see RFC 4342, 8.5 */ 6597c657876SArnaldo Carvalho de Melo break; 660b84a2189SArnaldo Carvalho de Melo case CCID3_FBACK_PARAM_CHANGE: 661b84a2189SArnaldo Carvalho de Melo /* 662b84a2189SArnaldo Carvalho de Melo * When parameters change (new loss or p > p_prev), we do not 663b84a2189SArnaldo Carvalho de Melo * have a reliable estimate for R_m of [RFC 3448, 6.2] and so 664b84a2189SArnaldo Carvalho de Melo * need to reuse the previous value of X_recv. However, when 665b84a2189SArnaldo Carvalho de Melo * X_recv was 0 (due to early loss), this would kill X down to 666b84a2189SArnaldo Carvalho de Melo * s/t_mbi (i.e. one packet in 64 seconds). 667b84a2189SArnaldo Carvalho de Melo * To avoid such drastic reduction, we approximate X_recv as 668b84a2189SArnaldo Carvalho de Melo * the number of bytes since last feedback. 669b84a2189SArnaldo Carvalho de Melo * This is a safe fallback, since X is bounded above by X_calc. 670b84a2189SArnaldo Carvalho de Melo */ 671842d1ef1SGerrit Renker if (hcrx->x_recv > 0) 672b84a2189SArnaldo Carvalho de Melo break; 673b84a2189SArnaldo Carvalho de Melo /* fall through */ 674b84a2189SArnaldo Carvalho de Melo case CCID3_FBACK_PERIODIC: 675842d1ef1SGerrit Renker delta = ktime_us_delta(now, hcrx->tstamp_last_feedback); 676b84a2189SArnaldo Carvalho de Melo if (delta <= 0) 677b84a2189SArnaldo Carvalho de Melo DCCP_BUG("delta (%ld) <= 0", (long)delta); 678b84a2189SArnaldo Carvalho de Melo else 679842d1ef1SGerrit Renker hcrx->x_recv = scaled_div32(hcrx->bytes_recv, delta); 6807c657876SArnaldo Carvalho de Melo break; 681b84a2189SArnaldo Carvalho de Melo default: 6827c657876SArnaldo Carvalho de Melo return; 6837c657876SArnaldo Carvalho de Melo } 6847c657876SArnaldo Carvalho de Melo 685842d1ef1SGerrit Renker ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", 686842d1ef1SGerrit Renker (long)delta, hcrx->x_recv, hcrx->p_inverse); 6877c657876SArnaldo Carvalho de Melo 688842d1ef1SGerrit Renker hcrx->tstamp_last_feedback = now; 689842d1ef1SGerrit Renker hcrx->last_counter = dccp_hdr(skb)->dccph_ccval; 690842d1ef1SGerrit Renker hcrx->bytes_recv = 0; 6917c657876SArnaldo Carvalho de Melo 692507d37cfSArnaldo Carvalho de Melo dp->dccps_hc_rx_insert_options = 1; 6937c657876SArnaldo Carvalho de Melo dccp_send_ack(sk); 6947c657876SArnaldo Carvalho de Melo } 6957c657876SArnaldo Carvalho de Melo 6962d0817d1SArnaldo Carvalho de Melo static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) 6977c657876SArnaldo Carvalho de Melo { 698b2e317f4SGerrit Renker const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); 69960fe62e7SAndrea Bittau __be32 x_recv, pinv; 7007c657876SArnaldo Carvalho de Melo 70159d203f9SArnaldo Carvalho de Melo if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) 7022d0817d1SArnaldo Carvalho de Melo return 0; 7037c657876SArnaldo Carvalho de Melo 7044fded33bSArnaldo Carvalho de Melo if (dccp_packet_without_ack(skb)) 7052d0817d1SArnaldo Carvalho de Melo return 0; 7064fded33bSArnaldo Carvalho de Melo 707842d1ef1SGerrit Renker x_recv = htonl(hcrx->x_recv); 708842d1ef1SGerrit Renker pinv = htonl(hcrx->p_inverse); 7092d0817d1SArnaldo Carvalho de Melo 710385ac2e3SGerrit Renker if (dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE, 7112d0817d1SArnaldo Carvalho de Melo &pinv, sizeof(pinv)) || 7124fded33bSArnaldo Carvalho de Melo dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE, 7132d0817d1SArnaldo Carvalho de Melo &x_recv, sizeof(x_recv))) 7142d0817d1SArnaldo Carvalho de Melo return -1; 7152d0817d1SArnaldo Carvalho de Melo 7162d0817d1SArnaldo Carvalho de Melo return 0; 7177c657876SArnaldo Carvalho de Melo } 7187c657876SArnaldo Carvalho de Melo 719954c2db8SGerrit Renker /** ccid3_first_li - Implements [RFC 3448, 6.3.1] 720954c2db8SGerrit Renker * 721954c2db8SGerrit Renker * Determine the length of the first loss interval via inverse lookup. 722954c2db8SGerrit Renker * Assume that X_recv can be computed by the throughput equation 723954c2db8SGerrit Renker * s 724954c2db8SGerrit Renker * X_recv = -------- 725954c2db8SGerrit Renker * R * fval 726954c2db8SGerrit Renker * Find some p such that f(p) = fval; return 1/p (scaled). 727954c2db8SGerrit Renker */ 728954c2db8SGerrit Renker static u32 ccid3_first_li(struct sock *sk) 729954c2db8SGerrit Renker { 730954c2db8SGerrit Renker struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); 731954c2db8SGerrit Renker u32 x_recv, p, delta; 732954c2db8SGerrit Renker u64 fval; 733954c2db8SGerrit Renker 734842d1ef1SGerrit Renker if (hcrx->rtt == 0) { 735954c2db8SGerrit Renker DCCP_WARN("No RTT estimate available, using fallback RTT\n"); 736842d1ef1SGerrit Renker hcrx->rtt = DCCP_FALLBACK_RTT; 737954c2db8SGerrit Renker } 738954c2db8SGerrit Renker 739842d1ef1SGerrit Renker delta = ktime_to_us(net_timedelta(hcrx->tstamp_last_feedback)); 740842d1ef1SGerrit Renker x_recv = scaled_div32(hcrx->bytes_recv, delta); 741954c2db8SGerrit Renker if (x_recv == 0) { /* would also trigger divide-by-zero */ 742954c2db8SGerrit Renker DCCP_WARN("X_recv==0\n"); 743842d1ef1SGerrit Renker if (hcrx->x_recv == 0) { 744954c2db8SGerrit Renker DCCP_BUG("stored value of X_recv is zero"); 745954c2db8SGerrit Renker return ~0U; 746954c2db8SGerrit Renker } 747842d1ef1SGerrit Renker x_recv = hcrx->x_recv; 748954c2db8SGerrit Renker } 749954c2db8SGerrit Renker 750842d1ef1SGerrit Renker fval = scaled_div(hcrx->s, hcrx->rtt); 751954c2db8SGerrit Renker fval = scaled_div32(fval, x_recv); 752954c2db8SGerrit Renker p = tfrc_calc_x_reverse_lookup(fval); 753954c2db8SGerrit Renker 754954c2db8SGerrit Renker ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied " 755954c2db8SGerrit Renker "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); 756954c2db8SGerrit Renker 757954c2db8SGerrit Renker return p == 0 ? ~0U : scaled_div(1, p); 758954c2db8SGerrit Renker } 759954c2db8SGerrit Renker 7607c657876SArnaldo Carvalho de Melo static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) 7617c657876SArnaldo Carvalho de Melo { 76259725dc2SArnaldo Carvalho de Melo struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); 763b84a2189SArnaldo Carvalho de Melo enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE; 7645b5d0e70SGerrit Renker const u64 ndp = dccp_sk(sk)->dccps_options_received.dccpor_ndp; 765b84a2189SArnaldo Carvalho de Melo const bool is_data_packet = dccp_data_packet(skb); 7661f2333aeSArnaldo Carvalho de Melo 767842d1ef1SGerrit Renker if (unlikely(hcrx->state == TFRC_RSTATE_NO_DATA)) { 768b84a2189SArnaldo Carvalho de Melo if (is_data_packet) { 769b84a2189SArnaldo Carvalho de Melo const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; 770b84a2189SArnaldo Carvalho de Melo do_feedback = CCID3_FBACK_INITIAL; 7717c657876SArnaldo Carvalho de Melo ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); 772842d1ef1SGerrit Renker hcrx->s = payload; 773b84a2189SArnaldo Carvalho de Melo /* 774842d1ef1SGerrit Renker * Not necessary to update bytes_recv here, 775b84a2189SArnaldo Carvalho de Melo * since X_recv = 0 for the first feedback packet (cf. 776b84a2189SArnaldo Carvalho de Melo * RFC 3448, 6.3) -- gerrit 777b84a2189SArnaldo Carvalho de Melo */ 7787c657876SArnaldo Carvalho de Melo } 779b84a2189SArnaldo Carvalho de Melo goto update_records; 7807c657876SArnaldo Carvalho de Melo } 7817c657876SArnaldo Carvalho de Melo 782842d1ef1SGerrit Renker if (tfrc_rx_hist_duplicate(&hcrx->hist, skb)) 783b84a2189SArnaldo Carvalho de Melo return; /* done receiving */ 7847c657876SArnaldo Carvalho de Melo 785b84a2189SArnaldo Carvalho de Melo if (is_data_packet) { 786b84a2189SArnaldo Carvalho de Melo const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; 787b84a2189SArnaldo Carvalho de Melo /* 788b84a2189SArnaldo Carvalho de Melo * Update moving-average of s and the sum of received payload bytes 789b84a2189SArnaldo Carvalho de Melo */ 790842d1ef1SGerrit Renker hcrx->s = tfrc_ewma(hcrx->s, payload, 9); 791842d1ef1SGerrit Renker hcrx->bytes_recv += payload; 7927c657876SArnaldo Carvalho de Melo } 793b84a2189SArnaldo Carvalho de Melo 794b84a2189SArnaldo Carvalho de Melo /* 795b552c623SGerrit Renker * Perform loss detection and handle pending losses 796b84a2189SArnaldo Carvalho de Melo */ 797842d1ef1SGerrit Renker if (tfrc_rx_handle_loss(&hcrx->hist, &hcrx->li_hist, 798954c2db8SGerrit Renker skb, ndp, ccid3_first_li, sk)) { 799954c2db8SGerrit Renker do_feedback = CCID3_FBACK_PARAM_CHANGE; 800954c2db8SGerrit Renker goto done_receiving; 801954c2db8SGerrit Renker } 802954c2db8SGerrit Renker 803842d1ef1SGerrit Renker if (tfrc_rx_hist_loss_pending(&hcrx->hist)) 804b552c623SGerrit Renker return; /* done receiving */ 805b84a2189SArnaldo Carvalho de Melo 806b84a2189SArnaldo Carvalho de Melo /* 807b84a2189SArnaldo Carvalho de Melo * Handle data packets: RTT sampling and monitoring p 808b84a2189SArnaldo Carvalho de Melo */ 809b84a2189SArnaldo Carvalho de Melo if (unlikely(!is_data_packet)) 810b84a2189SArnaldo Carvalho de Melo goto update_records; 811b84a2189SArnaldo Carvalho de Melo 812842d1ef1SGerrit Renker if (!tfrc_lh_is_initialised(&hcrx->li_hist)) { 813842d1ef1SGerrit Renker const u32 sample = tfrc_rx_hist_sample_rtt(&hcrx->hist, skb); 814b84a2189SArnaldo Carvalho de Melo /* 815b84a2189SArnaldo Carvalho de Melo * Empty loss history: no loss so far, hence p stays 0. 816b84a2189SArnaldo Carvalho de Melo * Sample RTT values, since an RTT estimate is required for the 817b84a2189SArnaldo Carvalho de Melo * computation of p when the first loss occurs; RFC 3448, 6.3.1. 818b84a2189SArnaldo Carvalho de Melo */ 819b84a2189SArnaldo Carvalho de Melo if (sample != 0) 820842d1ef1SGerrit Renker hcrx->rtt = tfrc_ewma(hcrx->rtt, sample, 9); 821954c2db8SGerrit Renker 822842d1ef1SGerrit Renker } else if (tfrc_lh_update_i_mean(&hcrx->li_hist, skb)) { 823954c2db8SGerrit Renker /* 824954c2db8SGerrit Renker * Step (3) of [RFC 3448, 6.1]: Recompute I_mean and, if I_mean 825954c2db8SGerrit Renker * has decreased (resp. p has increased), send feedback now. 826954c2db8SGerrit Renker */ 827954c2db8SGerrit Renker do_feedback = CCID3_FBACK_PARAM_CHANGE; 828b84a2189SArnaldo Carvalho de Melo } 829b84a2189SArnaldo Carvalho de Melo 830b84a2189SArnaldo Carvalho de Melo /* 831b84a2189SArnaldo Carvalho de Melo * Check if the periodic once-per-RTT feedback is due; RFC 4342, 10.3 832b84a2189SArnaldo Carvalho de Melo */ 833842d1ef1SGerrit Renker if (SUB16(dccp_hdr(skb)->dccph_ccval, hcrx->last_counter) > 3) 834b84a2189SArnaldo Carvalho de Melo do_feedback = CCID3_FBACK_PERIODIC; 835b84a2189SArnaldo Carvalho de Melo 836b84a2189SArnaldo Carvalho de Melo update_records: 837842d1ef1SGerrit Renker tfrc_rx_hist_add_packet(&hcrx->hist, skb, ndp); 838b84a2189SArnaldo Carvalho de Melo 839954c2db8SGerrit Renker done_receiving: 840b84a2189SArnaldo Carvalho de Melo if (do_feedback) 841b84a2189SArnaldo Carvalho de Melo ccid3_hc_rx_send_feedback(sk, skb, do_feedback); 8427c657876SArnaldo Carvalho de Melo } 8437c657876SArnaldo Carvalho de Melo 84491f0ebf7SArnaldo Carvalho de Melo static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk) 8457c657876SArnaldo Carvalho de Melo { 84691f0ebf7SArnaldo Carvalho de Melo struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid); 8477c657876SArnaldo Carvalho de Melo 848842d1ef1SGerrit Renker hcrx->state = TFRC_RSTATE_NO_DATA; 849842d1ef1SGerrit Renker tfrc_lh_init(&hcrx->li_hist); 850842d1ef1SGerrit Renker return tfrc_rx_hist_alloc(&hcrx->hist); 8517c657876SArnaldo Carvalho de Melo } 8527c657876SArnaldo Carvalho de Melo 8537c657876SArnaldo Carvalho de Melo static void ccid3_hc_rx_exit(struct sock *sk) 8547c657876SArnaldo Carvalho de Melo { 85559725dc2SArnaldo Carvalho de Melo struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); 8567c657876SArnaldo Carvalho de Melo 8577c657876SArnaldo Carvalho de Melo ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM); 8587c657876SArnaldo Carvalho de Melo 859842d1ef1SGerrit Renker tfrc_rx_hist_purge(&hcrx->hist); 860842d1ef1SGerrit Renker tfrc_lh_cleanup(&hcrx->li_hist); 8617c657876SArnaldo Carvalho de Melo } 8627c657876SArnaldo Carvalho de Melo 8632babe1f6SArnaldo Carvalho de Melo static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) 8642babe1f6SArnaldo Carvalho de Melo { 865b2e317f4SGerrit Renker info->tcpi_ca_state = ccid3_hc_rx_sk(sk)->state; 8662babe1f6SArnaldo Carvalho de Melo info->tcpi_options |= TCPI_OPT_TIMESTAMPS; 867b2e317f4SGerrit Renker info->tcpi_rcv_rtt = ccid3_hc_rx_sk(sk)->rtt; 8682babe1f6SArnaldo Carvalho de Melo } 8692babe1f6SArnaldo Carvalho de Melo 87088f964dbSArnaldo Carvalho de Melo static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, 87188f964dbSArnaldo Carvalho de Melo u32 __user *optval, int __user *optlen) 87288f964dbSArnaldo Carvalho de Melo { 873b2e317f4SGerrit Renker const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); 8748e138e79SGerrit Renker struct tfrc_rx_info rx_info; 87588f964dbSArnaldo Carvalho de Melo const void *val; 87688f964dbSArnaldo Carvalho de Melo 87788f964dbSArnaldo Carvalho de Melo switch (optname) { 87888f964dbSArnaldo Carvalho de Melo case DCCP_SOCKOPT_CCID_RX_INFO: 8798e138e79SGerrit Renker if (len < sizeof(rx_info)) 88088f964dbSArnaldo Carvalho de Melo return -EINVAL; 881842d1ef1SGerrit Renker rx_info.tfrcrx_x_recv = hcrx->x_recv; 882842d1ef1SGerrit Renker rx_info.tfrcrx_rtt = hcrx->rtt; 883842d1ef1SGerrit Renker rx_info.tfrcrx_p = hcrx->p_inverse == 0 ? ~0U : 884842d1ef1SGerrit Renker scaled_div(1, hcrx->p_inverse); 8858e138e79SGerrit Renker len = sizeof(rx_info); 8868e138e79SGerrit Renker val = &rx_info; 88788f964dbSArnaldo Carvalho de Melo break; 88888f964dbSArnaldo Carvalho de Melo default: 88988f964dbSArnaldo Carvalho de Melo return -ENOPROTOOPT; 89088f964dbSArnaldo Carvalho de Melo } 89188f964dbSArnaldo Carvalho de Melo 89288f964dbSArnaldo Carvalho de Melo if (put_user(len, optlen) || copy_to_user(optval, val, len)) 89388f964dbSArnaldo Carvalho de Melo return -EFAULT; 89488f964dbSArnaldo Carvalho de Melo 89588f964dbSArnaldo Carvalho de Melo return 0; 89688f964dbSArnaldo Carvalho de Melo } 89788f964dbSArnaldo Carvalho de Melo 89891f0ebf7SArnaldo Carvalho de Melo static struct ccid_operations ccid3 = { 8993dd9a7c3SIan McDonald .ccid_id = DCCPC_CCID3, 90084a97b0aSGerrit Renker .ccid_name = "TCP-Friendly Rate Control", 9017c657876SArnaldo Carvalho de Melo .ccid_owner = THIS_MODULE, 90291f0ebf7SArnaldo Carvalho de Melo .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock), 9037c657876SArnaldo Carvalho de Melo .ccid_hc_tx_init = ccid3_hc_tx_init, 9047c657876SArnaldo Carvalho de Melo .ccid_hc_tx_exit = ccid3_hc_tx_exit, 9057c657876SArnaldo Carvalho de Melo .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, 9067c657876SArnaldo Carvalho de Melo .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, 9077c657876SArnaldo Carvalho de Melo .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, 9087c657876SArnaldo Carvalho de Melo .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, 90991f0ebf7SArnaldo Carvalho de Melo .ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock), 9107c657876SArnaldo Carvalho de Melo .ccid_hc_rx_init = ccid3_hc_rx_init, 9117c657876SArnaldo Carvalho de Melo .ccid_hc_rx_exit = ccid3_hc_rx_exit, 9127c657876SArnaldo Carvalho de Melo .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, 9137c657876SArnaldo Carvalho de Melo .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, 9142babe1f6SArnaldo Carvalho de Melo .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, 9152babe1f6SArnaldo Carvalho de Melo .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, 91688f964dbSArnaldo Carvalho de Melo .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt, 91788f964dbSArnaldo Carvalho de Melo .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt, 9187c657876SArnaldo Carvalho de Melo }; 9197c657876SArnaldo Carvalho de Melo 92056724aa4SGerrit Renker #ifdef CONFIG_IP_DCCP_CCID3_DEBUG 92143264991SGerrit Renker module_param(ccid3_debug, bool, 0644); 9227c657876SArnaldo Carvalho de Melo MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); 92356724aa4SGerrit Renker #endif 9247c657876SArnaldo Carvalho de Melo 9257c657876SArnaldo Carvalho de Melo static __init int ccid3_module_init(void) 9267c657876SArnaldo Carvalho de Melo { 92734a9e7eaSArnaldo Carvalho de Melo return ccid_register(&ccid3); 9287c657876SArnaldo Carvalho de Melo } 9297c657876SArnaldo Carvalho de Melo module_init(ccid3_module_init); 9307c657876SArnaldo Carvalho de Melo 9317c657876SArnaldo Carvalho de Melo static __exit void ccid3_module_exit(void) 9327c657876SArnaldo Carvalho de Melo { 9337c657876SArnaldo Carvalho de Melo ccid_unregister(&ccid3); 9347c657876SArnaldo Carvalho de Melo } 9357c657876SArnaldo Carvalho de Melo module_exit(ccid3_module_exit); 9367c657876SArnaldo Carvalho de Melo 937e6bccd35SIan McDonald MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, " 9381f2333aeSArnaldo Carvalho de Melo "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); 9397c657876SArnaldo Carvalho de Melo MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); 9407c657876SArnaldo Carvalho de Melo MODULE_LICENSE("GPL"); 9417c657876SArnaldo Carvalho de Melo MODULE_ALIAS("net-dccp-ccid-3"); 942