Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 1 | /* |
| 2 | * net/dccp/ccids/ccid3.c |
| 3 | * |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 4 | * Copyright (c) 2007 The University of Aberdeen, Scotland, UK |
Ian McDonald | b2f41ff | 2007-05-28 12:23:29 -0300 | [diff] [blame] | 5 | * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. |
| 6 | * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz> |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 7 | * |
| 8 | * An implementation of the DCCP protocol |
| 9 | * |
| 10 | * This code has been developed by the University of Waikato WAND |
| 11 | * research group. For further information please see http://www.wand.net.nz/ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 12 | * |
| 13 | * This code also uses code from Lulea University, rereleased as GPL by its |
| 14 | * authors: |
| 15 | * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon |
| 16 | * |
| 17 | * Changes to meet Linux coding standards, to make it meet latest ccid3 draft |
| 18 | * and to make it work as a loadable module in the DCCP stack written by |
| 19 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br>. |
| 20 | * |
| 21 | * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| 22 | * |
| 23 | * This program is free software; you can redistribute it and/or modify |
| 24 | * it under the terms of the GNU General Public License as published by |
| 25 | * the Free Software Foundation; either version 2 of the License, or |
| 26 | * (at your option) any later version. |
| 27 | * |
| 28 | * This program is distributed in the hope that it will be useful, |
| 29 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 30 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 31 | * GNU General Public License for more details. |
| 32 | * |
| 33 | * You should have received a copy of the GNU General Public License |
| 34 | * along with this program; if not, write to the Free Software |
| 35 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 36 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 37 | #include "../dccp.h" |
| 38 | #include "ccid3.h" |
| 39 | |
Gerrit Renker | 76fd1e8 | 2007-10-24 10:46:58 -0200 | [diff] [blame] | 40 | #include <asm/unaligned.h> |
| 41 | |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 42 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
| 43 | static int ccid3_debug; |
| 44 | #define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 45 | #else |
| 46 | #define ccid3_pr_debug(format, a...) |
| 47 | #endif |
| 48 | |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 49 | /* |
| 50 | * Transmitter Half-Connection Routines |
| 51 | */ |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 52 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 53 | static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) |
| 54 | { |
| 55 | static char *ccid3_state_names[] = { |
| 56 | [TFRC_SSTATE_NO_SENT] = "NO_SENT", |
| 57 | [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", |
| 58 | [TFRC_SSTATE_FBACK] = "FBACK", |
| 59 | [TFRC_SSTATE_TERM] = "TERM", |
| 60 | }; |
| 61 | |
| 62 | return ccid3_state_names[state]; |
| 63 | } |
| 64 | #endif |
| 65 | |
Arnaldo Carvalho de Melo | c25a18b | 2006-03-20 21:58:56 -0800 | [diff] [blame] | 66 | static void ccid3_hc_tx_set_state(struct sock *sk, |
| 67 | enum ccid3_hc_tx_states state) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 68 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 69 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 70 | enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state; |
| 71 | |
| 72 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 73 | dccp_role(sk), sk, ccid3_tx_state_name(oldstate), |
| 74 | ccid3_tx_state_name(state)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 75 | WARN_ON(state == oldstate); |
| 76 | hctx->ccid3hctx_state = state; |
| 77 | } |
| 78 | |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 79 | /* |
Gerrit Renker | 6c08b2c | 2007-11-20 17:33:17 -0200 | [diff] [blame] | 80 | * Compute the initial sending rate X_init in the manner of RFC 3390: |
| 81 | * |
| 82 | * X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT |
| 83 | * |
| 84 | * Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis |
| 85 | * (rev-02) clarifies the use of RFC 3390 with regard to the above formula. |
Gerrit Renker | a21f9f9 | 2007-03-20 15:12:10 -0300 | [diff] [blame] | 86 | * For consistency with other parts of the code, X_init is scaled by 2^6. |
| 87 | */ |
| 88 | static inline u64 rfc3390_initial_rate(struct sock *sk) |
| 89 | { |
Gerrit Renker | 6c08b2c | 2007-11-20 17:33:17 -0200 | [diff] [blame] | 90 | const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
| 91 | const __u32 w_init = min_t(__u32, 4 * hctx->ccid3hctx_s, |
| 92 | max_t(__u32, 2 * hctx->ccid3hctx_s, 4380)); |
Gerrit Renker | a21f9f9 | 2007-03-20 15:12:10 -0300 | [diff] [blame] | 93 | |
Gerrit Renker | 6c08b2c | 2007-11-20 17:33:17 -0200 | [diff] [blame] | 94 | return scaled_div(w_init << 6, hctx->ccid3hctx_rtt); |
Gerrit Renker | a21f9f9 | 2007-03-20 15:12:10 -0300 | [diff] [blame] | 95 | } |
| 96 | |
| 97 | /* |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 98 | * Recalculate t_ipi and delta (should be called whenever X changes) |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 99 | */ |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 100 | static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 101 | { |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 102 | /* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */ |
Gerrit Renker | b2449fd | 2007-04-20 13:02:55 -0700 | [diff] [blame] | 103 | hctx->ccid3hctx_t_ipi = scaled_div32(((u64)hctx->ccid3hctx_s) << 6, |
| 104 | hctx->ccid3hctx_x); |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 105 | |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 106 | /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 107 | hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2, |
| 108 | TFRC_OPSYS_HALF_TIME_GRAN); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 109 | |
Gerrit Renker | 1761f7d | 2007-03-20 15:04:30 -0300 | [diff] [blame] | 110 | ccid3_pr_debug("t_ipi=%u, delta=%u, s=%u, X=%u\n", |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 111 | hctx->ccid3hctx_t_ipi, hctx->ccid3hctx_delta, |
Gerrit Renker | 1761f7d | 2007-03-20 15:04:30 -0300 | [diff] [blame] | 112 | hctx->ccid3hctx_s, (unsigned)(hctx->ccid3hctx_x >> 6)); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 113 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 114 | } |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 115 | |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 116 | static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hctx, ktime_t now) |
| 117 | { |
| 118 | u32 delta = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count); |
| 119 | |
| 120 | return delta / hctx->ccid3hctx_rtt; |
| 121 | } |
| 122 | |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 123 | /** |
| 124 | * ccid3_hc_tx_update_x - Update allowed sending rate X |
| 125 | * @stamp: most recent time if available - can be left NULL. |
| 126 | * This function tracks draft rfc3448bis, check there for latest details. |
Gerrit Renker | 5c3fbb6 | 2006-12-03 14:50:56 -0200 | [diff] [blame] | 127 | * |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 128 | * Note: X and X_recv are both stored in units of 64 * bytes/second, to support |
| 129 | * fine-grained resolution of sending rates. This requires scaling by 2^6 |
| 130 | * throughout the code. Only X_calc is unscaled (in bytes/second). |
| 131 | * |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 132 | */ |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 133 | static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp) |
Gerrit Renker | a79ef76 | 2006-11-28 19:51:42 -0200 | [diff] [blame] | 134 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 135 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 136 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 137 | __u64 min_rate = 2 * hctx->ccid3hctx_x_recv; |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 138 | const __u64 old_x = hctx->ccid3hctx_x; |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 139 | ktime_t now = stamp? *stamp : ktime_get_real(); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 140 | |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 141 | /* |
| 142 | * Handle IDLE periods: do not reduce below RFC3390 initial sending rate |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 143 | * when idling [RFC 4342, 5.1]. Definition of idling is from rfc3448bis: |
| 144 | * a sender is idle if it has not sent anything over a 2-RTT-period. |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 145 | * For consistency with X and X_recv, min_rate is also scaled by 2^6. |
| 146 | */ |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 147 | if (ccid3_hc_tx_idle_rtt(hctx, now) >= 2) { |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 148 | min_rate = rfc3390_initial_rate(sk); |
| 149 | min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv); |
| 150 | } |
| 151 | |
Gerrit Renker | 4415830 | 2006-12-03 14:53:07 -0200 | [diff] [blame] | 152 | if (hctx->ccid3hctx_p > 0) { |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 153 | |
Gerrit Renker | 9e8efc8 | 2006-12-10 00:24:57 -0200 | [diff] [blame] | 154 | hctx->ccid3hctx_x = min(((__u64)hctx->ccid3hctx_x_calc) << 6, |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 155 | min_rate); |
Gerrit Renker | 9e8efc8 | 2006-12-10 00:24:57 -0200 | [diff] [blame] | 156 | hctx->ccid3hctx_x = max(hctx->ccid3hctx_x, |
| 157 | (((__u64)hctx->ccid3hctx_s) << 6) / |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 158 | TFRC_T_MBI); |
Arnaldo Carvalho de Melo | b6ee3d4 | 2005-08-27 18:18:18 -0300 | [diff] [blame] | 159 | |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 160 | } else if (ktime_us_delta(now, hctx->ccid3hctx_t_ld) |
| 161 | - (s64)hctx->ccid3hctx_rtt >= 0) { |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 162 | |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 163 | hctx->ccid3hctx_x = |
| 164 | max(min(2 * hctx->ccid3hctx_x, min_rate), |
| 165 | scaled_div(((__u64)hctx->ccid3hctx_s) << 6, |
| 166 | hctx->ccid3hctx_rtt)); |
| 167 | hctx->ccid3hctx_t_ld = now; |
Gerrit Renker | ff58629 | 2006-12-10 00:00:14 -0200 | [diff] [blame] | 168 | } |
Gerrit Renker | a79ef76 | 2006-11-28 19:51:42 -0200 | [diff] [blame] | 169 | |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 170 | if (hctx->ccid3hctx_x != old_x) { |
Gerrit Renker | 1761f7d | 2007-03-20 15:04:30 -0300 | [diff] [blame] | 171 | ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, " |
| 172 | "X_recv=%u\n", (unsigned)(old_x >> 6), |
| 173 | (unsigned)(hctx->ccid3hctx_x >> 6), |
| 174 | hctx->ccid3hctx_x_calc, |
| 175 | (unsigned)(hctx->ccid3hctx_x_recv >> 6)); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 176 | |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 177 | ccid3_update_send_interval(hctx); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 178 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 179 | } |
| 180 | |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 181 | /* |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 182 | * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1) |
| 183 | * @len: DCCP packet payload size in bytes |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 184 | */ |
| 185 | static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len) |
| 186 | { |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 187 | const u16 old_s = hctx->ccid3hctx_s; |
| 188 | |
Gerrit Renker | c3ada46 | 2007-11-20 18:09:59 -0200 | [diff] [blame] | 189 | hctx->ccid3hctx_s = tfrc_ewma(hctx->ccid3hctx_s, len, 9); |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 190 | |
| 191 | if (hctx->ccid3hctx_s != old_s) |
| 192 | ccid3_update_send_interval(hctx); |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 193 | } |
| 194 | |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 195 | /* |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 196 | * Update Window Counter using the algorithm from [RFC 4342, 8.1]. |
| 197 | * The algorithm is not applicable if RTT < 4 microseconds. |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 198 | */ |
| 199 | static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hctx, |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 200 | ktime_t now) |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 201 | { |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 202 | u32 quarter_rtts; |
| 203 | |
| 204 | if (unlikely(hctx->ccid3hctx_rtt < 4)) /* avoid divide-by-zero */ |
| 205 | return; |
| 206 | |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 207 | quarter_rtts = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count); |
| 208 | quarter_rtts /= hctx->ccid3hctx_rtt / 4; |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 209 | |
| 210 | if (quarter_rtts > 0) { |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 211 | hctx->ccid3hctx_t_last_win_count = now; |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 212 | hctx->ccid3hctx_last_win_count += min_t(u32, quarter_rtts, 5); |
| 213 | hctx->ccid3hctx_last_win_count &= 0xF; /* mod 16 */ |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 214 | } |
| 215 | } |
| 216 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 217 | static void ccid3_hc_tx_no_feedback_timer(unsigned long data) |
| 218 | { |
| 219 | struct sock *sk = (struct sock *)data; |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 220 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 2a1fda6 | 2006-11-28 18:34:34 -0200 | [diff] [blame] | 221 | unsigned long t_nfb = USEC_PER_SEC / 5; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 222 | |
| 223 | bh_lock_sock(sk); |
| 224 | if (sock_owned_by_user(sk)) { |
| 225 | /* Try again later. */ |
| 226 | /* XXX: set some sensible MIB */ |
Gerrit Renker | 48e03ee | 2006-11-27 20:29:27 -0200 | [diff] [blame] | 227 | goto restart_timer; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 228 | } |
| 229 | |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 230 | ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 231 | ccid3_tx_state_name(hctx->ccid3hctx_state)); |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 232 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 233 | switch (hctx->ccid3hctx_state) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 234 | case TFRC_SSTATE_NO_FBACK: |
Gerrit Renker | a79ef76 | 2006-11-28 19:51:42 -0200 | [diff] [blame] | 235 | /* RFC 3448, 4.4: Halve send rate directly */ |
Gerrit Renker | 9e8efc8 | 2006-12-10 00:24:57 -0200 | [diff] [blame] | 236 | hctx->ccid3hctx_x = max(hctx->ccid3hctx_x / 2, |
| 237 | (((__u64)hctx->ccid3hctx_s) << 6) / |
| 238 | TFRC_T_MBI); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 239 | |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 240 | ccid3_pr_debug("%s(%p, state=%s), updated tx rate to %u " |
| 241 | "bytes/s\n", dccp_role(sk), sk, |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 242 | ccid3_tx_state_name(hctx->ccid3hctx_state), |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 243 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
Gerrit Renker | 48e03ee | 2006-11-27 20:29:27 -0200 | [diff] [blame] | 244 | /* The value of R is still undefined and so we can not recompute |
Joe Perches | 5e8e034 | 2007-12-20 13:59:39 -0800 | [diff] [blame] | 245 | * the timeout value. Keep initial value as per [RFC 4342, 5]. */ |
Gerrit Renker | 2a1fda6 | 2006-11-28 18:34:34 -0200 | [diff] [blame] | 246 | t_nfb = TFRC_INITIAL_TIMEOUT; |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 247 | ccid3_update_send_interval(hctx); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 248 | break; |
| 249 | case TFRC_SSTATE_FBACK: |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 250 | /* |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 251 | * Modify the cached value of X_recv [RFC 3448, 4.4] |
| 252 | * |
| 253 | * If (p == 0 || X_calc > 2 * X_recv) |
| 254 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); |
| 255 | * Else |
| 256 | * X_recv = X_calc / 4; |
| 257 | * |
| 258 | * Note that X_recv is scaled by 2^6 while X_calc is not |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 259 | */ |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 260 | BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc); |
Gerrit Renker | a79ef76 | 2006-11-28 19:51:42 -0200 | [diff] [blame] | 261 | |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 262 | if (hctx->ccid3hctx_p == 0 || |
| 263 | (hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))) { |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 264 | |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 265 | hctx->ccid3hctx_x_recv = |
| 266 | max(hctx->ccid3hctx_x_recv / 2, |
| 267 | (((__u64)hctx->ccid3hctx_s) << 6) / |
| 268 | (2 * TFRC_T_MBI)); |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 269 | } else { |
| 270 | hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc; |
| 271 | hctx->ccid3hctx_x_recv <<= 4; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 272 | } |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 273 | /* Now recalculate X [RFC 3448, 4.3, step (4)] */ |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 274 | ccid3_hc_tx_update_x(sk, NULL); |
Arnaldo Carvalho de Melo | 6b5e633 | 2005-08-27 20:11:28 -0300 | [diff] [blame] | 275 | /* |
| 276 | * Schedule no feedback timer to expire in |
Gerrit Renker | 8a508ac | 2006-12-03 14:50:23 -0200 | [diff] [blame] | 277 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
| 278 | * See comments in packet_recv() regarding the value of t_RTO. |
Arnaldo Carvalho de Melo | 6b5e633 | 2005-08-27 20:11:28 -0300 | [diff] [blame] | 279 | */ |
Gerrit Renker | 8a508ac | 2006-12-03 14:50:23 -0200 | [diff] [blame] | 280 | t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 281 | break; |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 282 | case TFRC_SSTATE_NO_SENT: |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 283 | DCCP_BUG("%s(%p) - Illegal state NO_SENT", dccp_role(sk), sk); |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 284 | /* fall through */ |
| 285 | case TFRC_SSTATE_TERM: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 286 | goto out; |
| 287 | } |
| 288 | |
Gerrit Renker | 48e03ee | 2006-11-27 20:29:27 -0200 | [diff] [blame] | 289 | restart_timer: |
| 290 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 291 | jiffies + usecs_to_jiffies(t_nfb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 292 | out: |
| 293 | bh_unlock_sock(sk); |
| 294 | sock_put(sk); |
| 295 | } |
| 296 | |
Gerrit Renker | 7da7f45 | 2006-11-27 12:26:03 -0200 | [diff] [blame] | 297 | /* |
| 298 | * returns |
| 299 | * > 0: delay (in msecs) that should pass before actually sending |
| 300 | * = 0: can send immediately |
| 301 | * < 0: error condition; do not send packet |
| 302 | */ |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 303 | static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 304 | { |
| 305 | struct dccp_sock *dp = dccp_sk(sk); |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 306 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 307 | ktime_t now = ktime_get_real(); |
| 308 | s64 delay; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 309 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 310 | /* |
Gerrit Renker | da335ba | 2006-11-27 12:26:57 -0200 | [diff] [blame] | 311 | * This function is called only for Data and DataAck packets. Sending |
| 312 | * zero-sized Data(Ack)s is theoretically possible, but for congestion |
| 313 | * control this case is pathological - ignore it. |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 314 | */ |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 315 | if (unlikely(skb->len == 0)) |
Gerrit Renker | da335ba | 2006-11-27 12:26:57 -0200 | [diff] [blame] | 316 | return -EBADMSG; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 317 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 318 | switch (hctx->ccid3hctx_state) { |
| 319 | case TFRC_SSTATE_NO_SENT: |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 320 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 321 | (jiffies + |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 322 | usecs_to_jiffies(TFRC_INITIAL_TIMEOUT))); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 323 | hctx->ccid3hctx_last_win_count = 0; |
| 324 | hctx->ccid3hctx_t_last_win_count = now; |
Gerrit Renker | 90feeb9 | 2006-11-27 12:13:38 -0200 | [diff] [blame] | 325 | |
| 326 | /* Set t_0 for initial packet */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 327 | hctx->ccid3hctx_t_nom = now; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 328 | |
| 329 | hctx->ccid3hctx_s = skb->len; |
| 330 | |
| 331 | /* |
| 332 | * Use initial RTT sample when available: recommended by erratum |
| 333 | * to RFC 4342. This implements the initialisation procedure of |
| 334 | * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6. |
| 335 | */ |
| 336 | if (dp->dccps_syn_rtt) { |
| 337 | ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt); |
| 338 | hctx->ccid3hctx_rtt = dp->dccps_syn_rtt; |
| 339 | hctx->ccid3hctx_x = rfc3390_initial_rate(sk); |
Arnaldo Carvalho de Melo | 23f062a | 2007-08-19 17:14:52 -0700 | [diff] [blame] | 340 | hctx->ccid3hctx_t_ld = now; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 341 | } else { |
Gerrit Renker | 6c08b2c | 2007-11-20 17:33:17 -0200 | [diff] [blame] | 342 | /* Sender does not have RTT sample: X_pps = 1 pkt/sec */ |
| 343 | hctx->ccid3hctx_x = hctx->ccid3hctx_s; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 344 | hctx->ccid3hctx_x <<= 6; |
| 345 | } |
| 346 | ccid3_update_send_interval(hctx); |
| 347 | |
| 348 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 349 | break; |
| 350 | case TFRC_SSTATE_NO_FBACK: |
| 351 | case TFRC_SSTATE_FBACK: |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 352 | delay = ktime_us_delta(hctx->ccid3hctx_t_nom, now); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 353 | ccid3_pr_debug("delay=%ld\n", (long)delay); |
Gerrit Renker | 91cf5a1 | 2006-11-27 12:25:10 -0200 | [diff] [blame] | 354 | /* |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 355 | * Scheduling of packet transmissions [RFC 3448, 4.6] |
Gerrit Renker | 91cf5a1 | 2006-11-27 12:25:10 -0200 | [diff] [blame] | 356 | * |
| 357 | * if (t_now > t_nom - delta) |
| 358 | * // send the packet now |
| 359 | * else |
| 360 | * // send the packet in (t_nom - t_now) milliseconds. |
| 361 | */ |
Gerrit Renker | 49d66a7 | 2007-06-16 13:48:50 -0300 | [diff] [blame] | 362 | if (delay - (s64)hctx->ccid3hctx_delta >= 1000) |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 363 | return (u32)delay / 1000L; |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 364 | |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 365 | ccid3_hc_tx_update_win_count(hctx, now); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 366 | break; |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 367 | case TFRC_SSTATE_TERM: |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 368 | DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); |
Gerrit Renker | 7da7f45 | 2006-11-27 12:26:03 -0200 | [diff] [blame] | 369 | return -EINVAL; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 370 | } |
| 371 | |
Gerrit Renker | 7da7f45 | 2006-11-27 12:26:03 -0200 | [diff] [blame] | 372 | /* prepare to send now (add options etc.) */ |
| 373 | dp->dccps_hc_tx_insert_options = 1; |
Gerrit Renker | e312d10 | 2006-12-10 00:08:09 -0200 | [diff] [blame] | 374 | DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; |
| 375 | |
| 376 | /* set the nominal send time for the next following packet */ |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 377 | hctx->ccid3hctx_t_nom = ktime_add_us(hctx->ccid3hctx_t_nom, |
| 378 | hctx->ccid3hctx_t_ipi); |
Gerrit Renker | 7da7f45 | 2006-11-27 12:26:03 -0200 | [diff] [blame] | 379 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 380 | } |
| 381 | |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 382 | static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, |
| 383 | unsigned int len) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 384 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 385 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 386 | |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 387 | ccid3_hc_tx_update_s(hctx, len); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 388 | |
Arnaldo Carvalho de Melo | 276f2ed | 2007-11-28 11:15:40 -0200 | [diff] [blame] | 389 | if (tfrc_tx_hist_add(&hctx->ccid3hctx_hist, dccp_sk(sk)->dccps_gss)) |
Gerrit Renker | c5a1ae9 | 2006-12-10 00:09:21 -0200 | [diff] [blame] | 390 | DCCP_CRIT("packet history - out of memory!"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 391 | } |
| 392 | |
| 393 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) |
| 394 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 395 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 396 | struct ccid3_options_received *opt_recv; |
Arnaldo Carvalho de Melo | 0740d49 | 2007-08-19 17:18:13 -0700 | [diff] [blame] | 397 | ktime_t now; |
Gerrit Renker | 2a1fda6 | 2006-11-28 18:34:34 -0200 | [diff] [blame] | 398 | unsigned long t_nfb; |
Gerrit Renker | 7dfee1a | 2007-03-20 15:24:37 -0300 | [diff] [blame] | 399 | u32 pinv, r_sample; |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 400 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 401 | /* we are only interested in ACKs */ |
| 402 | if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || |
| 403 | DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) |
| 404 | return; |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame^] | 405 | /* ... and only in the established state */ |
| 406 | if (hctx->ccid3hctx_state != TFRC_SSTATE_FBACK && |
| 407 | hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK) |
| 408 | return; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 409 | |
| 410 | opt_recv = &hctx->ccid3hctx_options_received; |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame^] | 411 | now = ktime_get_real(); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 412 | |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame^] | 413 | /* Estimate RTT from history if ACK number is valid */ |
| 414 | r_sample = tfrc_tx_hist_rtt(hctx->ccid3hctx_hist, |
| 415 | DCCP_SKB_CB(skb)->dccpd_ack_seq, now); |
| 416 | if (r_sample == 0) { |
| 417 | DCCP_WARN("%s(%p): %s with bogus ACK-%llu\n", dccp_role(sk), sk, |
| 418 | dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type), |
| 419 | (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq); |
| 420 | return; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 421 | } |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame^] | 422 | |
| 423 | /* Update receive rate in units of 64 * bytes/second */ |
| 424 | hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate; |
| 425 | hctx->ccid3hctx_x_recv <<= 6; |
| 426 | |
| 427 | /* Update loss event rate (which is scaled by 1e6) */ |
| 428 | pinv = opt_recv->ccid3or_loss_event_rate; |
| 429 | if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */ |
| 430 | hctx->ccid3hctx_p = 0; |
| 431 | else /* can not exceed 100% */ |
| 432 | hctx->ccid3hctx_p = 1000000 / pinv; |
| 433 | /* |
| 434 | * Validate new RTT sample and update moving average |
| 435 | */ |
| 436 | r_sample = dccp_sample_rtt(sk, r_sample); |
| 437 | hctx->ccid3hctx_rtt = tfrc_ewma(hctx->ccid3hctx_rtt, r_sample, 9); |
| 438 | |
| 439 | if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) { |
| 440 | /* |
| 441 | * Larger Initial Windows [RFC 4342, sec. 5] |
| 442 | */ |
| 443 | hctx->ccid3hctx_x = rfc3390_initial_rate(sk); |
| 444 | hctx->ccid3hctx_t_ld = now; |
| 445 | |
| 446 | ccid3_update_send_interval(hctx); |
| 447 | |
| 448 | ccid3_pr_debug("%s(%p), s=%u, MSS=%u, " |
| 449 | "R_sample=%uus, X=%u\n", dccp_role(sk), |
| 450 | sk, hctx->ccid3hctx_s, |
| 451 | dccp_sk(sk)->dccps_mss_cache, r_sample, |
| 452 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
| 453 | |
| 454 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); |
| 455 | } else { |
| 456 | |
| 457 | /* Update sending rate (step 4 of [RFC 3448, 4.3]) */ |
| 458 | if (hctx->ccid3hctx_p > 0) |
| 459 | hctx->ccid3hctx_x_calc = |
| 460 | tfrc_calc_x(hctx->ccid3hctx_s, |
| 461 | hctx->ccid3hctx_rtt, |
| 462 | hctx->ccid3hctx_p); |
| 463 | ccid3_hc_tx_update_x(sk, &now); |
| 464 | |
| 465 | ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, " |
| 466 | "p=%u, X_calc=%u, X_recv=%u, X=%u\n", |
| 467 | dccp_role(sk), |
| 468 | sk, hctx->ccid3hctx_rtt, r_sample, |
| 469 | hctx->ccid3hctx_s, hctx->ccid3hctx_p, |
| 470 | hctx->ccid3hctx_x_calc, |
| 471 | (unsigned)(hctx->ccid3hctx_x_recv >> 6), |
| 472 | (unsigned)(hctx->ccid3hctx_x >> 6)); |
| 473 | } |
| 474 | |
| 475 | /* unschedule no feedback timer */ |
| 476 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); |
| 477 | |
| 478 | /* |
| 479 | * As we have calculated new ipi, delta, t_nom it is possible |
| 480 | * that we now can send a packet, so wake up dccp_wait_for_ccid |
| 481 | */ |
| 482 | sk->sk_write_space(sk); |
| 483 | |
| 484 | /* |
| 485 | * Update timeout interval for the nofeedback timer. |
| 486 | * We use a configuration option to increase the lower bound. |
| 487 | * This can help avoid triggering the nofeedback timer too |
| 488 | * often ('spinning') on LANs with small RTTs. |
| 489 | */ |
| 490 | hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt, |
| 491 | (CONFIG_IP_DCCP_CCID3_RTO * |
| 492 | (USEC_PER_SEC / 1000))); |
| 493 | /* |
| 494 | * Schedule no feedback timer to expire in |
| 495 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
| 496 | */ |
| 497 | t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi); |
| 498 | |
| 499 | ccid3_pr_debug("%s(%p), Scheduled no feedback timer to " |
| 500 | "expire in %lu jiffies (%luus)\n", |
| 501 | dccp_role(sk), |
| 502 | sk, usecs_to_jiffies(t_nfb), t_nfb); |
| 503 | |
| 504 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, |
| 505 | jiffies + usecs_to_jiffies(t_nfb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 506 | } |
| 507 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 508 | static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 509 | unsigned char len, u16 idx, |
| 510 | unsigned char *value) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 511 | { |
| 512 | int rc = 0; |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 513 | const struct dccp_sock *dp = dccp_sk(sk); |
| 514 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 515 | struct ccid3_options_received *opt_recv; |
Gerrit Renker | 76fd1e8 | 2007-10-24 10:46:58 -0200 | [diff] [blame] | 516 | __be32 opt_val; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 517 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 518 | opt_recv = &hctx->ccid3hctx_options_received; |
| 519 | |
| 520 | if (opt_recv->ccid3or_seqno != dp->dccps_gsr) { |
| 521 | opt_recv->ccid3or_seqno = dp->dccps_gsr; |
| 522 | opt_recv->ccid3or_loss_event_rate = ~0; |
| 523 | opt_recv->ccid3or_loss_intervals_idx = 0; |
| 524 | opt_recv->ccid3or_loss_intervals_len = 0; |
| 525 | opt_recv->ccid3or_receive_rate = 0; |
| 526 | } |
| 527 | |
| 528 | switch (option) { |
| 529 | case TFRC_OPT_LOSS_EVENT_RATE: |
Arnaldo Carvalho de Melo | 59d203f | 2005-09-09 20:01:25 -0300 | [diff] [blame] | 530 | if (unlikely(len != 4)) { |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 531 | DCCP_WARN("%s(%p), invalid len %d " |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 532 | "for TFRC_OPT_LOSS_EVENT_RATE\n", |
| 533 | dccp_role(sk), sk, len); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 534 | rc = -EINVAL; |
| 535 | } else { |
Gerrit Renker | 76fd1e8 | 2007-10-24 10:46:58 -0200 | [diff] [blame] | 536 | opt_val = get_unaligned((__be32 *)value); |
| 537 | opt_recv->ccid3or_loss_event_rate = ntohl(opt_val); |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 538 | ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n", |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 539 | dccp_role(sk), sk, |
| 540 | opt_recv->ccid3or_loss_event_rate); |
| 541 | } |
| 542 | break; |
| 543 | case TFRC_OPT_LOSS_INTERVALS: |
| 544 | opt_recv->ccid3or_loss_intervals_idx = idx; |
| 545 | opt_recv->ccid3or_loss_intervals_len = len; |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 546 | ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n", |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 547 | dccp_role(sk), sk, |
| 548 | opt_recv->ccid3or_loss_intervals_idx, |
| 549 | opt_recv->ccid3or_loss_intervals_len); |
| 550 | break; |
| 551 | case TFRC_OPT_RECEIVE_RATE: |
Arnaldo Carvalho de Melo | 59d203f | 2005-09-09 20:01:25 -0300 | [diff] [blame] | 552 | if (unlikely(len != 4)) { |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 553 | DCCP_WARN("%s(%p), invalid len %d " |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 554 | "for TFRC_OPT_RECEIVE_RATE\n", |
| 555 | dccp_role(sk), sk, len); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 556 | rc = -EINVAL; |
| 557 | } else { |
Gerrit Renker | 76fd1e8 | 2007-10-24 10:46:58 -0200 | [diff] [blame] | 558 | opt_val = get_unaligned((__be32 *)value); |
| 559 | opt_recv->ccid3or_receive_rate = ntohl(opt_val); |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 560 | ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n", |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 561 | dccp_role(sk), sk, |
| 562 | opt_recv->ccid3or_receive_rate); |
| 563 | } |
| 564 | break; |
| 565 | } |
| 566 | |
| 567 | return rc; |
| 568 | } |
| 569 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 570 | static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 571 | { |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 572 | struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 573 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 574 | hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT; |
Arnaldo Carvalho de Melo | 276f2ed | 2007-11-28 11:15:40 -0200 | [diff] [blame] | 575 | hctx->ccid3hctx_hist = NULL; |
Pavel Emelyanov | b24b8a2 | 2008-01-23 21:20:07 -0800 | [diff] [blame] | 576 | setup_timer(&hctx->ccid3hctx_no_feedback_timer, |
| 577 | ccid3_hc_tx_no_feedback_timer, (unsigned long)sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 578 | |
| 579 | return 0; |
| 580 | } |
| 581 | |
| 582 | static void ccid3_hc_tx_exit(struct sock *sk) |
| 583 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 584 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 585 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 586 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM); |
| 587 | sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); |
| 588 | |
Arnaldo Carvalho de Melo | 276f2ed | 2007-11-28 11:15:40 -0200 | [diff] [blame] | 589 | tfrc_tx_hist_purge(&hctx->ccid3hctx_hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 590 | } |
| 591 | |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 592 | static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) |
| 593 | { |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 594 | struct ccid3_hc_tx_sock *hctx; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 595 | |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 596 | /* Listen socks doesn't have a private CCID block */ |
| 597 | if (sk->sk_state == DCCP_LISTEN) |
| 598 | return; |
| 599 | |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 600 | hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 601 | info->tcpi_rto = hctx->ccid3hctx_t_rto; |
| 602 | info->tcpi_rtt = hctx->ccid3hctx_rtt; |
| 603 | } |
| 604 | |
| 605 | static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, |
| 606 | u32 __user *optval, int __user *optlen) |
| 607 | { |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 608 | const struct ccid3_hc_tx_sock *hctx; |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 609 | const void *val; |
| 610 | |
| 611 | /* Listen socks doesn't have a private CCID block */ |
| 612 | if (sk->sk_state == DCCP_LISTEN) |
| 613 | return -EINVAL; |
| 614 | |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 615 | hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 616 | switch (optname) { |
| 617 | case DCCP_SOCKOPT_CCID_TX_INFO: |
| 618 | if (len < sizeof(hctx->ccid3hctx_tfrc)) |
| 619 | return -EINVAL; |
| 620 | len = sizeof(hctx->ccid3hctx_tfrc); |
| 621 | val = &hctx->ccid3hctx_tfrc; |
| 622 | break; |
| 623 | default: |
| 624 | return -ENOPROTOOPT; |
| 625 | } |
| 626 | |
| 627 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) |
| 628 | return -EFAULT; |
| 629 | |
| 630 | return 0; |
| 631 | } |
| 632 | |
| 633 | /* |
| 634 | * Receiver Half-Connection Routines |
| 635 | */ |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 636 | |
| 637 | /* CCID3 feedback types */ |
| 638 | enum ccid3_fback_type { |
| 639 | CCID3_FBACK_NONE = 0, |
| 640 | CCID3_FBACK_INITIAL, |
| 641 | CCID3_FBACK_PERIODIC, |
| 642 | CCID3_FBACK_PARAM_CHANGE |
| 643 | }; |
| 644 | |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 645 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 646 | static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) |
| 647 | { |
| 648 | static char *ccid3_rx_state_names[] = { |
| 649 | [TFRC_RSTATE_NO_DATA] = "NO_DATA", |
| 650 | [TFRC_RSTATE_DATA] = "DATA", |
| 651 | [TFRC_RSTATE_TERM] = "TERM", |
| 652 | }; |
| 653 | |
| 654 | return ccid3_rx_state_names[state]; |
| 655 | } |
| 656 | #endif |
| 657 | |
Arnaldo Carvalho de Melo | c25a18b | 2006-03-20 21:58:56 -0800 | [diff] [blame] | 658 | static void ccid3_hc_rx_set_state(struct sock *sk, |
| 659 | enum ccid3_hc_rx_states state) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 660 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 661 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 662 | enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state; |
| 663 | |
| 664 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 665 | dccp_role(sk), sk, ccid3_rx_state_name(oldstate), |
| 666 | ccid3_rx_state_name(state)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 667 | WARN_ON(state == oldstate); |
| 668 | hcrx->ccid3hcrx_state = state; |
| 669 | } |
| 670 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 671 | static void ccid3_hc_rx_send_feedback(struct sock *sk, |
| 672 | const struct sk_buff *skb, |
| 673 | enum ccid3_fback_type fbtype) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 674 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 675 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 676 | struct dccp_sock *dp = dccp_sk(sk); |
Arnaldo Carvalho de Melo | e7c2335 | 2007-08-19 17:17:51 -0700 | [diff] [blame] | 677 | ktime_t now; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 678 | s64 delta = 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 679 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 680 | if (unlikely(hcrx->ccid3hcrx_state == TFRC_RSTATE_TERM)) |
| 681 | return; |
| 682 | |
Arnaldo Carvalho de Melo | e7a81c6 | 2007-08-19 17:15:37 -0700 | [diff] [blame] | 683 | now = ktime_get_real(); |
Arnaldo Carvalho de Melo | b6ee3d4 | 2005-08-27 18:18:18 -0300 | [diff] [blame] | 684 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 685 | switch (fbtype) { |
| 686 | case CCID3_FBACK_INITIAL: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 687 | hcrx->ccid3hcrx_x_recv = 0; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 688 | hcrx->ccid3hcrx_pinv = ~0U; /* see RFC 4342, 8.5 */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 689 | break; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 690 | case CCID3_FBACK_PARAM_CHANGE: |
| 691 | /* |
| 692 | * When parameters change (new loss or p > p_prev), we do not |
| 693 | * have a reliable estimate for R_m of [RFC 3448, 6.2] and so |
| 694 | * need to reuse the previous value of X_recv. However, when |
| 695 | * X_recv was 0 (due to early loss), this would kill X down to |
| 696 | * s/t_mbi (i.e. one packet in 64 seconds). |
| 697 | * To avoid such drastic reduction, we approximate X_recv as |
| 698 | * the number of bytes since last feedback. |
| 699 | * This is a safe fallback, since X is bounded above by X_calc. |
| 700 | */ |
| 701 | if (hcrx->ccid3hcrx_x_recv > 0) |
| 702 | break; |
| 703 | /* fall through */ |
| 704 | case CCID3_FBACK_PERIODIC: |
| 705 | delta = ktime_us_delta(now, hcrx->ccid3hcrx_tstamp_last_feedback); |
| 706 | if (delta <= 0) |
| 707 | DCCP_BUG("delta (%ld) <= 0", (long)delta); |
| 708 | else |
| 709 | hcrx->ccid3hcrx_x_recv = |
| 710 | scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 711 | break; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 712 | default: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 713 | return; |
| 714 | } |
| 715 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 716 | ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", (long)delta, |
| 717 | hcrx->ccid3hcrx_x_recv, hcrx->ccid3hcrx_pinv); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 718 | |
Arnaldo Carvalho de Melo | b6ee3d4 | 2005-08-27 18:18:18 -0300 | [diff] [blame] | 719 | hcrx->ccid3hcrx_tstamp_last_feedback = now; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 720 | hcrx->ccid3hcrx_last_counter = dccp_hdr(skb)->dccph_ccval; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 721 | hcrx->ccid3hcrx_bytes_recv = 0; |
| 722 | |
Arnaldo Carvalho de Melo | 507d37c | 2005-09-09 02:30:07 -0300 | [diff] [blame] | 723 | dp->dccps_hc_rx_insert_options = 1; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 724 | dccp_send_ack(sk); |
| 725 | } |
| 726 | |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 727 | static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 728 | { |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 729 | const struct ccid3_hc_rx_sock *hcrx; |
Andrea Bittau | 60fe62e | 2006-03-20 19:23:32 -0800 | [diff] [blame] | 730 | __be32 x_recv, pinv; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 731 | |
Arnaldo Carvalho de Melo | 59d203f | 2005-09-09 20:01:25 -0300 | [diff] [blame] | 732 | if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 733 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 734 | |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 735 | hcrx = ccid3_hc_rx_sk(sk); |
Arnaldo Carvalho de Melo | 4fded33 | 2005-08-23 21:51:59 -0700 | [diff] [blame] | 736 | |
| 737 | if (dccp_packet_without_ack(skb)) |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 738 | return 0; |
| 739 | |
Arnaldo Carvalho de Melo | 4fded33 | 2005-08-23 21:51:59 -0700 | [diff] [blame] | 740 | x_recv = htonl(hcrx->ccid3hcrx_x_recv); |
| 741 | pinv = htonl(hcrx->ccid3hcrx_pinv); |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 742 | |
Gerrit Renker | 385ac2e | 2007-12-08 16:26:59 -0200 | [diff] [blame] | 743 | if (dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE, |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 744 | &pinv, sizeof(pinv)) || |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 745 | dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE, |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 746 | &x_recv, sizeof(x_recv))) |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 747 | return -1; |
| 748 | |
| 749 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 750 | } |
| 751 | |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 752 | /** ccid3_first_li - Implements [RFC 3448, 6.3.1] |
| 753 | * |
| 754 | * Determine the length of the first loss interval via inverse lookup. |
| 755 | * Assume that X_recv can be computed by the throughput equation |
| 756 | * s |
| 757 | * X_recv = -------- |
| 758 | * R * fval |
| 759 | * Find some p such that f(p) = fval; return 1/p (scaled). |
| 760 | */ |
| 761 | static u32 ccid3_first_li(struct sock *sk) |
| 762 | { |
| 763 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
| 764 | u32 x_recv, p, delta; |
| 765 | u64 fval; |
| 766 | |
| 767 | if (hcrx->ccid3hcrx_rtt == 0) { |
| 768 | DCCP_WARN("No RTT estimate available, using fallback RTT\n"); |
| 769 | hcrx->ccid3hcrx_rtt = DCCP_FALLBACK_RTT; |
| 770 | } |
| 771 | |
| 772 | delta = ktime_to_us(net_timedelta(hcrx->ccid3hcrx_tstamp_last_feedback)); |
| 773 | x_recv = scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta); |
| 774 | if (x_recv == 0) { /* would also trigger divide-by-zero */ |
| 775 | DCCP_WARN("X_recv==0\n"); |
| 776 | if ((x_recv = hcrx->ccid3hcrx_x_recv) == 0) { |
| 777 | DCCP_BUG("stored value of X_recv is zero"); |
| 778 | return ~0U; |
| 779 | } |
| 780 | } |
| 781 | |
| 782 | fval = scaled_div(hcrx->ccid3hcrx_s, hcrx->ccid3hcrx_rtt); |
| 783 | fval = scaled_div32(fval, x_recv); |
| 784 | p = tfrc_calc_x_reverse_lookup(fval); |
| 785 | |
| 786 | ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied " |
| 787 | "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); |
| 788 | |
| 789 | return p == 0 ? ~0U : scaled_div(1, p); |
| 790 | } |
| 791 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 792 | static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) |
| 793 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 794 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 795 | enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE; |
| 796 | const u32 ndp = dccp_sk(sk)->dccps_options_received.dccpor_ndp; |
| 797 | const bool is_data_packet = dccp_data_packet(skb); |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 798 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 799 | if (unlikely(hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)) { |
| 800 | if (is_data_packet) { |
| 801 | const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; |
| 802 | do_feedback = CCID3_FBACK_INITIAL; |
| 803 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); |
| 804 | hcrx->ccid3hcrx_s = payload; |
| 805 | /* |
| 806 | * Not necessary to update ccid3hcrx_bytes_recv here, |
| 807 | * since X_recv = 0 for the first feedback packet (cf. |
| 808 | * RFC 3448, 6.3) -- gerrit |
| 809 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 810 | } |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 811 | goto update_records; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 812 | } |
| 813 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 814 | if (tfrc_rx_hist_duplicate(&hcrx->ccid3hcrx_hist, skb)) |
| 815 | return; /* done receiving */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 816 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 817 | if (is_data_packet) { |
| 818 | const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; |
| 819 | /* |
| 820 | * Update moving-average of s and the sum of received payload bytes |
| 821 | */ |
| 822 | hcrx->ccid3hcrx_s = tfrc_ewma(hcrx->ccid3hcrx_s, payload, 9); |
| 823 | hcrx->ccid3hcrx_bytes_recv += payload; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 824 | } |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 825 | |
| 826 | /* |
| 827 | * Handle pending losses and otherwise check for new loss |
| 828 | */ |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 829 | if (tfrc_rx_hist_loss_pending(&hcrx->ccid3hcrx_hist) && |
| 830 | tfrc_rx_handle_loss(&hcrx->ccid3hcrx_hist, |
| 831 | &hcrx->ccid3hcrx_li_hist, |
| 832 | skb, ndp, ccid3_first_li, sk) ) { |
| 833 | do_feedback = CCID3_FBACK_PARAM_CHANGE; |
| 834 | goto done_receiving; |
| 835 | } |
| 836 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 837 | if (tfrc_rx_hist_new_loss_indicated(&hcrx->ccid3hcrx_hist, skb, ndp)) |
| 838 | goto update_records; |
| 839 | |
| 840 | /* |
| 841 | * Handle data packets: RTT sampling and monitoring p |
| 842 | */ |
| 843 | if (unlikely(!is_data_packet)) |
| 844 | goto update_records; |
| 845 | |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 846 | if (!tfrc_lh_is_initialised(&hcrx->ccid3hcrx_li_hist)) { |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 847 | const u32 sample = tfrc_rx_hist_sample_rtt(&hcrx->ccid3hcrx_hist, skb); |
| 848 | /* |
| 849 | * Empty loss history: no loss so far, hence p stays 0. |
| 850 | * Sample RTT values, since an RTT estimate is required for the |
| 851 | * computation of p when the first loss occurs; RFC 3448, 6.3.1. |
| 852 | */ |
| 853 | if (sample != 0) |
| 854 | hcrx->ccid3hcrx_rtt = tfrc_ewma(hcrx->ccid3hcrx_rtt, sample, 9); |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 855 | |
| 856 | } else if (tfrc_lh_update_i_mean(&hcrx->ccid3hcrx_li_hist, skb)) { |
| 857 | /* |
| 858 | * Step (3) of [RFC 3448, 6.1]: Recompute I_mean and, if I_mean |
| 859 | * has decreased (resp. p has increased), send feedback now. |
| 860 | */ |
| 861 | do_feedback = CCID3_FBACK_PARAM_CHANGE; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 862 | } |
| 863 | |
| 864 | /* |
| 865 | * Check if the periodic once-per-RTT feedback is due; RFC 4342, 10.3 |
| 866 | */ |
| 867 | if (SUB16(dccp_hdr(skb)->dccph_ccval, hcrx->ccid3hcrx_last_counter) > 3) |
| 868 | do_feedback = CCID3_FBACK_PERIODIC; |
| 869 | |
| 870 | update_records: |
| 871 | tfrc_rx_hist_add_packet(&hcrx->ccid3hcrx_hist, skb, ndp); |
| 872 | |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 873 | done_receiving: |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 874 | if (do_feedback) |
| 875 | ccid3_hc_rx_send_feedback(sk, skb, do_feedback); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 876 | } |
| 877 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 878 | static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 879 | { |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 880 | struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 881 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 882 | hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA; |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 883 | tfrc_lh_init(&hcrx->ccid3hcrx_li_hist); |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 884 | return tfrc_rx_hist_alloc(&hcrx->ccid3hcrx_hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 885 | } |
| 886 | |
| 887 | static void ccid3_hc_rx_exit(struct sock *sk) |
| 888 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 889 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 890 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 891 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM); |
| 892 | |
Arnaldo Carvalho de Melo | d58d1af | 2007-12-06 12:28:39 -0200 | [diff] [blame] | 893 | tfrc_rx_hist_purge(&hcrx->ccid3hcrx_hist); |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 894 | tfrc_lh_cleanup(&hcrx->ccid3hcrx_li_hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 895 | } |
| 896 | |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 897 | static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) |
| 898 | { |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 899 | const struct ccid3_hc_rx_sock *hcrx; |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 900 | |
Arnaldo Carvalho de Melo | 59c2353 | 2005-09-12 14:16:58 -0700 | [diff] [blame] | 901 | /* Listen socks doesn't have a private CCID block */ |
| 902 | if (sk->sk_state == DCCP_LISTEN) |
| 903 | return; |
| 904 | |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 905 | hcrx = ccid3_hc_rx_sk(sk); |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 906 | info->tcpi_ca_state = hcrx->ccid3hcrx_state; |
| 907 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; |
| 908 | info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt; |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 909 | } |
| 910 | |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 911 | static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, |
| 912 | u32 __user *optval, int __user *optlen) |
| 913 | { |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 914 | const struct ccid3_hc_rx_sock *hcrx; |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 915 | struct tfrc_rx_info rx_info; |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 916 | const void *val; |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 917 | |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 918 | /* Listen socks doesn't have a private CCID block */ |
| 919 | if (sk->sk_state == DCCP_LISTEN) |
| 920 | return -EINVAL; |
| 921 | |
Gerrit Renker | 2e86908 | 2007-09-26 11:24:28 -0300 | [diff] [blame] | 922 | hcrx = ccid3_hc_rx_sk(sk); |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 923 | switch (optname) { |
| 924 | case DCCP_SOCKOPT_CCID_RX_INFO: |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 925 | if (len < sizeof(rx_info)) |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 926 | return -EINVAL; |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 927 | rx_info.tfrcrx_x_recv = hcrx->ccid3hcrx_x_recv; |
| 928 | rx_info.tfrcrx_rtt = hcrx->ccid3hcrx_rtt; |
| 929 | rx_info.tfrcrx_p = hcrx->ccid3hcrx_pinv == 0 ? ~0U : |
| 930 | scaled_div(1, hcrx->ccid3hcrx_pinv); |
| 931 | len = sizeof(rx_info); |
| 932 | val = &rx_info; |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 933 | break; |
| 934 | default: |
| 935 | return -ENOPROTOOPT; |
| 936 | } |
| 937 | |
| 938 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) |
| 939 | return -EFAULT; |
| 940 | |
| 941 | return 0; |
| 942 | } |
| 943 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 944 | static struct ccid_operations ccid3 = { |
Ian McDonald | 3dd9a7c | 2006-09-22 14:26:44 +1200 | [diff] [blame] | 945 | .ccid_id = DCCPC_CCID3, |
Gerrit Renker | 84a97b0 | 2007-12-13 23:33:25 -0200 | [diff] [blame] | 946 | .ccid_name = "TCP-Friendly Rate Control", |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 947 | .ccid_owner = THIS_MODULE, |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 948 | .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock), |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 949 | .ccid_hc_tx_init = ccid3_hc_tx_init, |
| 950 | .ccid_hc_tx_exit = ccid3_hc_tx_exit, |
| 951 | .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, |
| 952 | .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, |
| 953 | .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 954 | .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 955 | .ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock), |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 956 | .ccid_hc_rx_init = ccid3_hc_rx_init, |
| 957 | .ccid_hc_rx_exit = ccid3_hc_rx_exit, |
| 958 | .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, |
| 959 | .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 960 | .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, |
| 961 | .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 962 | .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt, |
| 963 | .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 964 | }; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 965 | |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 966 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
Gerrit Renker | 042d18f | 2007-10-04 14:39:53 -0700 | [diff] [blame] | 967 | module_param(ccid3_debug, bool, 0444); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 968 | MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 969 | #endif |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 970 | |
| 971 | static __init int ccid3_module_init(void) |
| 972 | { |
Arnaldo Carvalho de Melo | 34a9e7e | 2007-12-06 12:28:13 -0200 | [diff] [blame] | 973 | return ccid_register(&ccid3); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 974 | } |
| 975 | module_init(ccid3_module_init); |
| 976 | |
| 977 | static __exit void ccid3_module_exit(void) |
| 978 | { |
| 979 | ccid_unregister(&ccid3); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 980 | } |
| 981 | module_exit(ccid3_module_exit); |
| 982 | |
Ian McDonald | e6bccd3 | 2006-08-26 19:01:30 -0700 | [diff] [blame] | 983 | MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, " |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 984 | "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 985 | MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); |
| 986 | MODULE_LICENSE("GPL"); |
| 987 | MODULE_ALIAS("net-dccp-ccid-3"); |