Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 1 | /* |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 2 | * Copyright (c) 2007 The University of Aberdeen, Scotland, UK |
Ian McDonald | b2f41ff | 2007-05-28 12:23:29 -0300 | [diff] [blame] | 3 | * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. |
| 4 | * 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] | 5 | * |
| 6 | * An implementation of the DCCP protocol |
| 7 | * |
| 8 | * This code has been developed by the University of Waikato WAND |
| 9 | * research group. For further information please see http://www.wand.net.nz/ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 10 | * |
| 11 | * This code also uses code from Lulea University, rereleased as GPL by its |
| 12 | * authors: |
| 13 | * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon |
| 14 | * |
| 15 | * Changes to meet Linux coding standards, to make it meet latest ccid3 draft |
| 16 | * and to make it work as a loadable module in the DCCP stack written by |
| 17 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br>. |
| 18 | * |
| 19 | * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| 20 | * |
| 21 | * This program is free software; you can redistribute it and/or modify |
| 22 | * it under the terms of the GNU General Public License as published by |
| 23 | * the Free Software Foundation; either version 2 of the License, or |
| 24 | * (at your option) any later version. |
| 25 | * |
| 26 | * This program is distributed in the hope that it will be useful, |
| 27 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 28 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 29 | * GNU General Public License for more details. |
| 30 | * |
| 31 | * You should have received a copy of the GNU General Public License |
| 32 | * along with this program; if not, write to the Free Software |
| 33 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 34 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 35 | #include "../dccp.h" |
| 36 | #include "ccid3.h" |
| 37 | |
Gerrit Renker | 76fd1e8 | 2007-10-24 10:46:58 -0200 | [diff] [blame] | 38 | #include <asm/unaligned.h> |
| 39 | |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 40 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
| 41 | static int ccid3_debug; |
| 42 | #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] | 43 | #else |
| 44 | #define ccid3_pr_debug(format, a...) |
| 45 | #endif |
| 46 | |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 47 | /* |
| 48 | * Transmitter Half-Connection Routines |
| 49 | */ |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 50 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
| 51 | static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) |
| 52 | { |
Jan Engelhardt | 36cbd3d | 2009-08-05 10:42:58 -0700 | [diff] [blame] | 53 | static const char *const ccid3_state_names[] = { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 54 | [TFRC_SSTATE_NO_SENT] = "NO_SENT", |
| 55 | [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", |
| 56 | [TFRC_SSTATE_FBACK] = "FBACK", |
| 57 | [TFRC_SSTATE_TERM] = "TERM", |
| 58 | }; |
| 59 | |
| 60 | return ccid3_state_names[state]; |
| 61 | } |
| 62 | #endif |
| 63 | |
| 64 | static void ccid3_hc_tx_set_state(struct sock *sk, |
| 65 | enum ccid3_hc_tx_states state) |
| 66 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 67 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
| 68 | enum ccid3_hc_tx_states oldstate = hc->tx_state; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 69 | |
| 70 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", |
| 71 | dccp_role(sk), sk, ccid3_tx_state_name(oldstate), |
| 72 | ccid3_tx_state_name(state)); |
| 73 | WARN_ON(state == oldstate); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 74 | hc->tx_state = state; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 75 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 76 | |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 77 | /* |
Gerrit Renker | 6c08b2c | 2007-11-20 17:33:17 -0200 | [diff] [blame] | 78 | * Compute the initial sending rate X_init in the manner of RFC 3390: |
| 79 | * |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 80 | * X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT |
Gerrit Renker | 6c08b2c | 2007-11-20 17:33:17 -0200 | [diff] [blame] | 81 | * |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 82 | * Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis |
| 83 | * (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] | 84 | * For consistency with other parts of the code, X_init is scaled by 2^6. |
| 85 | */ |
| 86 | static inline u64 rfc3390_initial_rate(struct sock *sk) |
| 87 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 88 | const struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
| 89 | const __u32 w_init = clamp_t(__u32, 4380U, 2 * hc->tx_s, 4 * hc->tx_s); |
Gerrit Renker | a21f9f9 | 2007-03-20 15:12:10 -0300 | [diff] [blame] | 90 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 91 | return scaled_div(w_init << 6, hc->tx_rtt); |
Gerrit Renker | a21f9f9 | 2007-03-20 15:12:10 -0300 | [diff] [blame] | 92 | } |
| 93 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 94 | /* |
| 95 | * Recalculate t_ipi and delta (should be called whenever X changes) |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 96 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 97 | static void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hc) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 98 | { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 99 | /* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 100 | hc->tx_t_ipi = scaled_div32(((u64)hc->tx_s) << 6, hc->tx_x); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 101 | |
| 102 | /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 103 | hc->tx_delta = min_t(u32, hc->tx_t_ipi / 2, TFRC_OPSYS_HALF_TIME_GRAN); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 104 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 105 | ccid3_pr_debug("t_ipi=%u, delta=%u, s=%u, X=%u\n", hc->tx_t_ipi, |
| 106 | hc->tx_delta, hc->tx_s, (unsigned)(hc->tx_x >> 6)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 107 | } |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 108 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 109 | static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hc, ktime_t now) |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 110 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 111 | u32 delta = ktime_us_delta(now, hc->tx_t_last_win_count); |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 112 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 113 | return delta / hc->tx_rtt; |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 114 | } |
| 115 | |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 116 | /** |
| 117 | * ccid3_hc_tx_update_x - Update allowed sending rate X |
| 118 | * @stamp: most recent time if available - can be left NULL. |
| 119 | * This function tracks draft rfc3448bis, check there for latest details. |
Gerrit Renker | 5c3fbb6 | 2006-12-03 14:50:56 -0200 | [diff] [blame] | 120 | * |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 121 | * Note: X and X_recv are both stored in units of 64 * bytes/second, to support |
| 122 | * fine-grained resolution of sending rates. This requires scaling by 2^6 |
| 123 | * throughout the code. Only X_calc is unscaled (in bytes/second). |
| 124 | * |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 125 | */ |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 126 | static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 127 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 128 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
| 129 | __u64 min_rate = 2 * hc->tx_x_recv; |
| 130 | const __u64 old_x = hc->tx_x; |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 131 | ktime_t now = stamp ? *stamp : ktime_get_real(); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 132 | |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 133 | /* |
| 134 | * Handle IDLE periods: do not reduce below RFC3390 initial sending rate |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 135 | * when idling [RFC 4342, 5.1]. Definition of idling is from rfc3448bis: |
| 136 | * 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] | 137 | * For consistency with X and X_recv, min_rate is also scaled by 2^6. |
| 138 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 139 | if (ccid3_hc_tx_idle_rtt(hc, now) >= 2) { |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 140 | min_rate = rfc3390_initial_rate(sk); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 141 | min_rate = max(min_rate, 2 * hc->tx_x_recv); |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 142 | } |
| 143 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 144 | if (hc->tx_p > 0) { |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 145 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 146 | hc->tx_x = min(((__u64)hc->tx_x_calc) << 6, min_rate); |
| 147 | hc->tx_x = max(hc->tx_x, (((__u64)hc->tx_s) << 6) / TFRC_T_MBI); |
Arnaldo Carvalho de Melo | b6ee3d4 | 2005-08-27 18:18:18 -0300 | [diff] [blame] | 148 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 149 | } else if (ktime_us_delta(now, hc->tx_t_ld) - (s64)hc->tx_rtt >= 0) { |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 150 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 151 | hc->tx_x = min(2 * hc->tx_x, min_rate); |
| 152 | hc->tx_x = max(hc->tx_x, |
| 153 | scaled_div(((__u64)hc->tx_s) << 6, hc->tx_rtt)); |
| 154 | hc->tx_t_ld = now; |
Gerrit Renker | ff58629 | 2006-12-10 00:00:14 -0200 | [diff] [blame] | 155 | } |
Gerrit Renker | a79ef76 | 2006-11-28 19:51:42 -0200 | [diff] [blame] | 156 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 157 | if (hc->tx_x != old_x) { |
Gerrit Renker | 1761f7d | 2007-03-20 15:04:30 -0300 | [diff] [blame] | 158 | ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, " |
| 159 | "X_recv=%u\n", (unsigned)(old_x >> 6), |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 160 | (unsigned)(hc->tx_x >> 6), hc->tx_x_calc, |
| 161 | (unsigned)(hc->tx_x_recv >> 6)); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 162 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 163 | ccid3_update_send_interval(hc); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 164 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 165 | } |
| 166 | |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 167 | /* |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 168 | * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1) |
| 169 | * @len: DCCP packet payload size in bytes |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 170 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 171 | static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hc, int len) |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 172 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 173 | const u16 old_s = hc->tx_s; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 174 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 175 | hc->tx_s = tfrc_ewma(hc->tx_s, len, 9); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 176 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 177 | if (hc->tx_s != old_s) |
| 178 | ccid3_update_send_interval(hc); |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 179 | } |
| 180 | |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 181 | /* |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 182 | * Update Window Counter using the algorithm from [RFC 4342, 8.1]. |
Gerrit Renker | 825de27 | 2008-05-27 06:33:54 -0700 | [diff] [blame] | 183 | * As elsewhere, RTT > 0 is assumed by using dccp_sample_rtt(). |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 184 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 185 | static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hc, |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 186 | ktime_t now) |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 187 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 188 | u32 delta = ktime_us_delta(now, hc->tx_t_last_win_count), |
| 189 | quarter_rtts = (4 * delta) / hc->tx_rtt; |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 190 | |
| 191 | if (quarter_rtts > 0) { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 192 | hc->tx_t_last_win_count = now; |
| 193 | hc->tx_last_win_count += min(quarter_rtts, 5U); |
| 194 | hc->tx_last_win_count &= 0xF; /* mod 16 */ |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 195 | } |
| 196 | } |
| 197 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 198 | static void ccid3_hc_tx_no_feedback_timer(unsigned long data) |
| 199 | { |
| 200 | struct sock *sk = (struct sock *)data; |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 201 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 2a1fda6 | 2006-11-28 18:34:34 -0200 | [diff] [blame] | 202 | unsigned long t_nfb = USEC_PER_SEC / 5; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 203 | |
| 204 | bh_lock_sock(sk); |
| 205 | if (sock_owned_by_user(sk)) { |
| 206 | /* Try again later. */ |
| 207 | /* XXX: set some sensible MIB */ |
Gerrit Renker | 48e03ee | 2006-11-27 20:29:27 -0200 | [diff] [blame] | 208 | goto restart_timer; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 209 | } |
| 210 | |
Frans Pop | b138338 | 2010-03-24 07:57:28 +0000 | [diff] [blame] | 211 | ccid3_pr_debug("%s(%p, state=%s) - entry\n", dccp_role(sk), sk, |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 212 | ccid3_tx_state_name(hc->tx_state)); |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 213 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 214 | if (hc->tx_state == TFRC_SSTATE_FBACK) |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 215 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 216 | else if (hc->tx_state != TFRC_SSTATE_NO_FBACK) |
Gerrit Renker | d0995e6 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 217 | goto out; |
| 218 | |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 219 | /* |
| 220 | * Determine new allowed sending rate X as per draft rfc3448bis-00, 4.4 |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 221 | * RTO is 0 if and only if no feedback has been received yet. |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 222 | */ |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 223 | if (hc->tx_t_rto == 0 || hc->tx_p == 0) { |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 224 | |
| 225 | /* halve send rate directly */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 226 | hc->tx_x = max(hc->tx_x / 2, |
| 227 | (((__u64)hc->tx_s) << 6) / TFRC_T_MBI); |
| 228 | ccid3_update_send_interval(hc); |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 229 | } else { |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 230 | /* |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 231 | * Modify the cached value of X_recv |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 232 | * |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 233 | * If (X_calc > 2 * X_recv) |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 234 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); |
| 235 | * Else |
| 236 | * X_recv = X_calc / 4; |
| 237 | * |
| 238 | * 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] | 239 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 240 | BUG_ON(hc->tx_p && !hc->tx_x_calc); |
Gerrit Renker | a79ef76 | 2006-11-28 19:51:42 -0200 | [diff] [blame] | 241 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 242 | if (hc->tx_x_calc > (hc->tx_x_recv >> 5)) |
| 243 | hc->tx_x_recv = |
| 244 | max(hc->tx_x_recv / 2, |
| 245 | (((__u64)hc->tx_s) << 6) / (2*TFRC_T_MBI)); |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 246 | else { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 247 | hc->tx_x_recv = hc->tx_x_calc; |
| 248 | hc->tx_x_recv <<= 4; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 249 | } |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 250 | ccid3_hc_tx_update_x(sk, NULL); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 251 | } |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 252 | ccid3_pr_debug("Reduced X to %llu/64 bytes/sec\n", |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 253 | (unsigned long long)hc->tx_x); |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 254 | |
| 255 | /* |
| 256 | * Set new timeout for the nofeedback timer. |
| 257 | * See comments in packet_recv() regarding the value of t_RTO. |
| 258 | */ |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 259 | if (unlikely(hc->tx_t_rto == 0)) /* no feedback received yet */ |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 260 | t_nfb = TFRC_INITIAL_TIMEOUT; |
| 261 | else |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 262 | t_nfb = max(hc->tx_t_rto, 2 * hc->tx_t_ipi); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 263 | |
Gerrit Renker | 48e03ee | 2006-11-27 20:29:27 -0200 | [diff] [blame] | 264 | restart_timer: |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 265 | sk_reset_timer(sk, &hc->tx_no_feedback_timer, |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 266 | jiffies + usecs_to_jiffies(t_nfb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 267 | out: |
| 268 | bh_unlock_sock(sk); |
| 269 | sock_put(sk); |
| 270 | } |
| 271 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 272 | /* |
| 273 | * returns |
| 274 | * > 0: delay (in msecs) that should pass before actually sending |
| 275 | * = 0: can send immediately |
| 276 | * < 0: error condition; do not send packet |
Gerrit Renker | 7da7f45 | 2006-11-27 12:26:03 -0200 | [diff] [blame] | 277 | */ |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 278 | 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] | 279 | { |
| 280 | struct dccp_sock *dp = dccp_sk(sk); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 281 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 282 | ktime_t now = ktime_get_real(); |
| 283 | s64 delay; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 284 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 285 | /* |
Gerrit Renker | da335ba | 2006-11-27 12:26:57 -0200 | [diff] [blame] | 286 | * This function is called only for Data and DataAck packets. Sending |
| 287 | * zero-sized Data(Ack)s is theoretically possible, but for congestion |
| 288 | * control this case is pathological - ignore it. |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 289 | */ |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 290 | if (unlikely(skb->len == 0)) |
Gerrit Renker | da335ba | 2006-11-27 12:26:57 -0200 | [diff] [blame] | 291 | return -EBADMSG; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 292 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 293 | switch (hc->tx_state) { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 294 | case TFRC_SSTATE_NO_SENT: |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 295 | sk_reset_timer(sk, &hc->tx_no_feedback_timer, (jiffies + |
| 296 | usecs_to_jiffies(TFRC_INITIAL_TIMEOUT))); |
| 297 | hc->tx_last_win_count = 0; |
| 298 | hc->tx_t_last_win_count = now; |
Gerrit Renker | 90feeb9 | 2006-11-27 12:13:38 -0200 | [diff] [blame] | 299 | |
| 300 | /* Set t_0 for initial packet */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 301 | hc->tx_t_nom = now; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 302 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 303 | hc->tx_s = skb->len; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 304 | |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 305 | /* |
| 306 | * Use initial RTT sample when available: recommended by erratum |
| 307 | * to RFC 4342. This implements the initialisation procedure of |
| 308 | * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6. |
| 309 | */ |
| 310 | if (dp->dccps_syn_rtt) { |
| 311 | ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 312 | hc->tx_rtt = dp->dccps_syn_rtt; |
| 313 | hc->tx_x = rfc3390_initial_rate(sk); |
| 314 | hc->tx_t_ld = now; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 315 | } else { |
Gerrit Renker | 3294f20 | 2008-06-11 11:19:09 +0100 | [diff] [blame] | 316 | /* |
| 317 | * Sender does not have RTT sample: |
| 318 | * - set fallback RTT (RFC 4340, 3.4) since a RTT value |
| 319 | * is needed in several parts (e.g. window counter); |
| 320 | * - set sending rate X_pps = 1pps as per RFC 3448, 4.2. |
| 321 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 322 | hc->tx_rtt = DCCP_FALLBACK_RTT; |
| 323 | hc->tx_x = hc->tx_s; |
| 324 | hc->tx_x <<= 6; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 325 | } |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 326 | ccid3_update_send_interval(hc); |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 327 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 328 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); |
| 329 | break; |
| 330 | case TFRC_SSTATE_NO_FBACK: |
| 331 | case TFRC_SSTATE_FBACK: |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 332 | delay = ktime_us_delta(hc->tx_t_nom, now); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 333 | ccid3_pr_debug("delay=%ld\n", (long)delay); |
Gerrit Renker | 91cf5a1 | 2006-11-27 12:25:10 -0200 | [diff] [blame] | 334 | /* |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 335 | * Scheduling of packet transmissions [RFC 3448, 4.6] |
Gerrit Renker | 91cf5a1 | 2006-11-27 12:25:10 -0200 | [diff] [blame] | 336 | * |
| 337 | * if (t_now > t_nom - delta) |
| 338 | * // send the packet now |
| 339 | * else |
| 340 | * // send the packet in (t_nom - t_now) milliseconds. |
| 341 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 342 | if (delay - (s64)hc->tx_delta >= 1000) |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 343 | return (u32)delay / 1000L; |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 344 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 345 | ccid3_hc_tx_update_win_count(hc, now); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 346 | break; |
| 347 | case TFRC_SSTATE_TERM: |
| 348 | DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk); |
| 349 | return -EINVAL; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 350 | } |
| 351 | |
Gerrit Renker | 7da7f45 | 2006-11-27 12:26:03 -0200 | [diff] [blame] | 352 | /* prepare to send now (add options etc.) */ |
| 353 | dp->dccps_hc_tx_insert_options = 1; |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 354 | DCCP_SKB_CB(skb)->dccpd_ccval = hc->tx_last_win_count; |
Gerrit Renker | e312d10 | 2006-12-10 00:08:09 -0200 | [diff] [blame] | 355 | |
| 356 | /* set the nominal send time for the next following packet */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 357 | hc->tx_t_nom = ktime_add_us(hc->tx_t_nom, hc->tx_t_ipi); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 358 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 359 | } |
| 360 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 361 | static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, |
| 362 | unsigned int len) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 363 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 364 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 365 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 366 | ccid3_hc_tx_update_s(hc, len); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 367 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 368 | if (tfrc_tx_hist_add(&hc->tx_hist, dccp_sk(sk)->dccps_gss)) |
Gerrit Renker | c5a1ae9 | 2006-12-10 00:09:21 -0200 | [diff] [blame] | 369 | DCCP_CRIT("packet history - out of memory!"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 370 | } |
| 371 | |
| 372 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) |
| 373 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 374 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 375 | struct ccid3_options_received *opt_recv = &hc->tx_options_received; |
Arnaldo Carvalho de Melo | 0740d49 | 2007-08-19 17:18:13 -0700 | [diff] [blame] | 376 | ktime_t now; |
Gerrit Renker | 2a1fda6 | 2006-11-28 18:34:34 -0200 | [diff] [blame] | 377 | unsigned long t_nfb; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 378 | u32 pinv, r_sample; |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 379 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 380 | /* we are only interested in ACKs */ |
| 381 | if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || |
| 382 | DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) |
| 383 | return; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 384 | /* ... and only in the established state */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 385 | if (hc->tx_state != TFRC_SSTATE_FBACK && |
| 386 | hc->tx_state != TFRC_SSTATE_NO_FBACK) |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 387 | return; |
Gerrit Renker | 63b3a73 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 388 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 389 | now = ktime_get_real(); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 390 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 391 | /* Estimate RTT from history if ACK number is valid */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 392 | r_sample = tfrc_tx_hist_rtt(hc->tx_hist, |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 393 | DCCP_SKB_CB(skb)->dccpd_ack_seq, now); |
| 394 | if (r_sample == 0) { |
| 395 | DCCP_WARN("%s(%p): %s with bogus ACK-%llu\n", dccp_role(sk), sk, |
| 396 | dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type), |
| 397 | (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq); |
| 398 | return; |
| 399 | } |
| 400 | |
| 401 | /* Update receive rate in units of 64 * bytes/second */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 402 | hc->tx_x_recv = opt_recv->ccid3or_receive_rate; |
| 403 | hc->tx_x_recv <<= 6; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 404 | |
| 405 | /* Update loss event rate (which is scaled by 1e6) */ |
| 406 | pinv = opt_recv->ccid3or_loss_event_rate; |
| 407 | if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 408 | hc->tx_p = 0; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 409 | else /* can not exceed 100% */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 410 | hc->tx_p = scaled_div(1, pinv); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 411 | /* |
| 412 | * Validate new RTT sample and update moving average |
| 413 | */ |
| 414 | r_sample = dccp_sample_rtt(sk, r_sample); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 415 | hc->tx_rtt = tfrc_ewma(hc->tx_rtt, r_sample, 9); |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 416 | /* |
| 417 | * Update allowed sending rate X as per draft rfc3448bis-00, 4.2/3 |
| 418 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 419 | if (hc->tx_state == TFRC_SSTATE_NO_FBACK) { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 420 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 421 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 422 | if (hc->tx_t_rto == 0) { |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 423 | /* |
| 424 | * Initial feedback packet: Larger Initial Windows (4.2) |
| 425 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 426 | hc->tx_x = rfc3390_initial_rate(sk); |
| 427 | hc->tx_t_ld = now; |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 428 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 429 | ccid3_update_send_interval(hc); |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 430 | |
| 431 | goto done_computing_x; |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 432 | } else if (hc->tx_p == 0) { |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 433 | /* |
| 434 | * First feedback after nofeedback timer expiry (4.3) |
| 435 | */ |
| 436 | goto done_computing_x; |
| 437 | } |
| 438 | } |
| 439 | |
| 440 | /* Update sending rate (step 4 of [RFC 3448, 4.3]) */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 441 | if (hc->tx_p > 0) |
| 442 | hc->tx_x_calc = tfrc_calc_x(hc->tx_s, hc->tx_rtt, hc->tx_p); |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 443 | ccid3_hc_tx_update_x(sk, &now); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 444 | |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 445 | done_computing_x: |
| 446 | ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, " |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 447 | "p=%u, X_calc=%u, X_recv=%u, X=%u\n", |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 448 | dccp_role(sk), sk, hc->tx_rtt, r_sample, |
| 449 | hc->tx_s, hc->tx_p, hc->tx_x_calc, |
| 450 | (unsigned)(hc->tx_x_recv >> 6), |
| 451 | (unsigned)(hc->tx_x >> 6)); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 452 | |
| 453 | /* unschedule no feedback timer */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 454 | sk_stop_timer(sk, &hc->tx_no_feedback_timer); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 455 | |
| 456 | /* |
| 457 | * As we have calculated new ipi, delta, t_nom it is possible |
| 458 | * that we now can send a packet, so wake up dccp_wait_for_ccid |
| 459 | */ |
| 460 | sk->sk_write_space(sk); |
| 461 | |
| 462 | /* |
| 463 | * Update timeout interval for the nofeedback timer. |
| 464 | * We use a configuration option to increase the lower bound. |
| 465 | * This can help avoid triggering the nofeedback timer too |
| 466 | * often ('spinning') on LANs with small RTTs. |
| 467 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 468 | hc->tx_t_rto = max_t(u32, 4 * hc->tx_rtt, (CONFIG_IP_DCCP_CCID3_RTO * |
Gerrit Renker | 388d5e9 | 2009-10-05 00:53:11 +0000 | [diff] [blame] | 469 | (USEC_PER_SEC / 1000))); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 470 | /* |
| 471 | * Schedule no feedback timer to expire in |
| 472 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
| 473 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 474 | t_nfb = max(hc->tx_t_rto, 2 * hc->tx_t_ipi); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 475 | |
| 476 | ccid3_pr_debug("%s(%p), Scheduled no feedback timer to " |
| 477 | "expire in %lu jiffies (%luus)\n", |
Gerrit Renker | 388d5e9 | 2009-10-05 00:53:11 +0000 | [diff] [blame] | 478 | dccp_role(sk), sk, usecs_to_jiffies(t_nfb), t_nfb); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 479 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 480 | sk_reset_timer(sk, &hc->tx_no_feedback_timer, |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 481 | jiffies + usecs_to_jiffies(t_nfb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 482 | } |
| 483 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 484 | static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, |
| 485 | unsigned char len, u16 idx, |
| 486 | unsigned char *value) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 487 | { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 488 | int rc = 0; |
| 489 | const struct dccp_sock *dp = dccp_sk(sk); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 490 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 491 | struct ccid3_options_received *opt_recv = &hc->tx_options_received; |
Gerrit Renker | 76fd1e8 | 2007-10-24 10:46:58 -0200 | [diff] [blame] | 492 | __be32 opt_val; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 493 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 494 | if (opt_recv->ccid3or_seqno != dp->dccps_gsr) { |
| 495 | opt_recv->ccid3or_seqno = dp->dccps_gsr; |
| 496 | opt_recv->ccid3or_loss_event_rate = ~0; |
| 497 | opt_recv->ccid3or_loss_intervals_idx = 0; |
| 498 | opt_recv->ccid3or_loss_intervals_len = 0; |
| 499 | opt_recv->ccid3or_receive_rate = 0; |
Gerrit Renker | 47a61e7 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 500 | } |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 501 | |
| 502 | switch (option) { |
| 503 | case TFRC_OPT_LOSS_EVENT_RATE: |
| 504 | if (unlikely(len != 4)) { |
| 505 | DCCP_WARN("%s(%p), invalid len %d " |
| 506 | "for TFRC_OPT_LOSS_EVENT_RATE\n", |
| 507 | dccp_role(sk), sk, len); |
| 508 | rc = -EINVAL; |
| 509 | } else { |
| 510 | opt_val = get_unaligned((__be32 *)value); |
| 511 | opt_recv->ccid3or_loss_event_rate = ntohl(opt_val); |
| 512 | ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n", |
| 513 | dccp_role(sk), sk, |
| 514 | opt_recv->ccid3or_loss_event_rate); |
| 515 | } |
| 516 | break; |
| 517 | case TFRC_OPT_LOSS_INTERVALS: |
| 518 | opt_recv->ccid3or_loss_intervals_idx = idx; |
| 519 | opt_recv->ccid3or_loss_intervals_len = len; |
| 520 | ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n", |
| 521 | dccp_role(sk), sk, |
| 522 | opt_recv->ccid3or_loss_intervals_idx, |
| 523 | opt_recv->ccid3or_loss_intervals_len); |
| 524 | break; |
| 525 | case TFRC_OPT_RECEIVE_RATE: |
| 526 | if (unlikely(len != 4)) { |
| 527 | DCCP_WARN("%s(%p), invalid len %d " |
| 528 | "for TFRC_OPT_RECEIVE_RATE\n", |
| 529 | dccp_role(sk), sk, len); |
| 530 | rc = -EINVAL; |
| 531 | } else { |
| 532 | opt_val = get_unaligned((__be32 *)value); |
| 533 | opt_recv->ccid3or_receive_rate = ntohl(opt_val); |
| 534 | ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n", |
| 535 | dccp_role(sk), sk, |
| 536 | opt_recv->ccid3or_receive_rate); |
| 537 | } |
| 538 | break; |
| 539 | } |
| 540 | |
| 541 | return rc; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 542 | } |
| 543 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 544 | 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] | 545 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 546 | struct ccid3_hc_tx_sock *hc = ccid_priv(ccid); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 547 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 548 | hc->tx_state = TFRC_SSTATE_NO_SENT; |
| 549 | hc->tx_hist = NULL; |
| 550 | setup_timer(&hc->tx_no_feedback_timer, |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 551 | ccid3_hc_tx_no_feedback_timer, (unsigned long)sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 552 | return 0; |
| 553 | } |
| 554 | |
| 555 | static void ccid3_hc_tx_exit(struct sock *sk) |
| 556 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 557 | struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 558 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 559 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 560 | sk_stop_timer(sk, &hc->tx_no_feedback_timer); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 561 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 562 | tfrc_tx_hist_purge(&hc->tx_hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 563 | } |
| 564 | |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 565 | static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) |
| 566 | { |
Gerrit Renker | 51c22bb | 2010-08-22 19:41:37 +0000 | [diff] [blame] | 567 | info->tcpi_rto = ccid3_hc_tx_sk(sk)->tx_t_rto; |
| 568 | info->tcpi_rtt = ccid3_hc_tx_sk(sk)->tx_rtt; |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 569 | } |
| 570 | |
| 571 | static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, |
| 572 | u32 __user *optval, int __user *optlen) |
| 573 | { |
Gerrit Renker | 51c22bb | 2010-08-22 19:41:37 +0000 | [diff] [blame] | 574 | const struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 575 | struct tfrc_tx_info tfrc; |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 576 | const void *val; |
| 577 | |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 578 | switch (optname) { |
| 579 | case DCCP_SOCKOPT_CCID_TX_INFO: |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 580 | if (len < sizeof(tfrc)) |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 581 | return -EINVAL; |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 582 | tfrc.tfrctx_x = hc->tx_x; |
| 583 | tfrc.tfrctx_x_recv = hc->tx_x_recv; |
| 584 | tfrc.tfrctx_x_calc = hc->tx_x_calc; |
| 585 | tfrc.tfrctx_rtt = hc->tx_rtt; |
| 586 | tfrc.tfrctx_p = hc->tx_p; |
| 587 | tfrc.tfrctx_rto = hc->tx_t_rto; |
| 588 | tfrc.tfrctx_ipi = hc->tx_t_ipi; |
| 589 | len = sizeof(tfrc); |
| 590 | val = &tfrc; |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 591 | break; |
| 592 | default: |
| 593 | return -ENOPROTOOPT; |
| 594 | } |
| 595 | |
| 596 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) |
| 597 | return -EFAULT; |
| 598 | |
| 599 | return 0; |
| 600 | } |
| 601 | |
| 602 | /* |
| 603 | * Receiver Half-Connection Routines |
| 604 | */ |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 605 | |
| 606 | /* CCID3 feedback types */ |
| 607 | enum ccid3_fback_type { |
| 608 | CCID3_FBACK_NONE = 0, |
| 609 | CCID3_FBACK_INITIAL, |
| 610 | CCID3_FBACK_PERIODIC, |
| 611 | CCID3_FBACK_PARAM_CHANGE |
| 612 | }; |
| 613 | |
| 614 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
| 615 | static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) |
| 616 | { |
Jan Engelhardt | 36cbd3d | 2009-08-05 10:42:58 -0700 | [diff] [blame] | 617 | static const char *const ccid3_rx_state_names[] = { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 618 | [TFRC_RSTATE_NO_DATA] = "NO_DATA", |
| 619 | [TFRC_RSTATE_DATA] = "DATA", |
| 620 | [TFRC_RSTATE_TERM] = "TERM", |
| 621 | }; |
| 622 | |
| 623 | return ccid3_rx_state_names[state]; |
| 624 | } |
| 625 | #endif |
| 626 | |
| 627 | static void ccid3_hc_rx_set_state(struct sock *sk, |
| 628 | enum ccid3_hc_rx_states state) |
| 629 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 630 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
| 631 | enum ccid3_hc_rx_states oldstate = hc->rx_state; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 632 | |
| 633 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", |
| 634 | dccp_role(sk), sk, ccid3_rx_state_name(oldstate), |
| 635 | ccid3_rx_state_name(state)); |
| 636 | WARN_ON(state == oldstate); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 637 | hc->rx_state = state; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 638 | } |
| 639 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 640 | static void ccid3_hc_rx_send_feedback(struct sock *sk, |
| 641 | const struct sk_buff *skb, |
| 642 | enum ccid3_fback_type fbtype) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 643 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 644 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 645 | struct dccp_sock *dp = dccp_sk(sk); |
| 646 | ktime_t now; |
| 647 | s64 delta = 0; |
| 648 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 649 | if (unlikely(hc->rx_state == TFRC_RSTATE_TERM)) |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 650 | return; |
| 651 | |
| 652 | now = ktime_get_real(); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 653 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 654 | switch (fbtype) { |
| 655 | case CCID3_FBACK_INITIAL: |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 656 | hc->rx_x_recv = 0; |
| 657 | hc->rx_pinv = ~0U; /* see RFC 4342, 8.5 */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 658 | break; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 659 | case CCID3_FBACK_PARAM_CHANGE: |
| 660 | /* |
| 661 | * When parameters change (new loss or p > p_prev), we do not |
| 662 | * have a reliable estimate for R_m of [RFC 3448, 6.2] and so |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 663 | * need to reuse the previous value of X_recv. However, when |
| 664 | * X_recv was 0 (due to early loss), this would kill X down to |
| 665 | * s/t_mbi (i.e. one packet in 64 seconds). |
| 666 | * To avoid such drastic reduction, we approximate X_recv as |
| 667 | * the number of bytes since last feedback. |
| 668 | * This is a safe fallback, since X is bounded above by X_calc. |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 669 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 670 | if (hc->rx_x_recv > 0) |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 671 | break; |
| 672 | /* fall through */ |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 673 | case CCID3_FBACK_PERIODIC: |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 674 | delta = ktime_us_delta(now, hc->rx_tstamp_last_feedback); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 675 | if (delta <= 0) |
| 676 | DCCP_BUG("delta (%ld) <= 0", (long)delta); |
| 677 | else |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 678 | hc->rx_x_recv = scaled_div32(hc->rx_bytes_recv, delta); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 679 | break; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 680 | default: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 681 | return; |
| 682 | } |
| 683 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 684 | ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", (long)delta, |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 685 | hc->rx_x_recv, hc->rx_pinv); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 686 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 687 | hc->rx_tstamp_last_feedback = now; |
| 688 | hc->rx_last_counter = dccp_hdr(skb)->dccph_ccval; |
| 689 | hc->rx_bytes_recv = 0; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 690 | |
| 691 | dp->dccps_hc_rx_insert_options = 1; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 692 | dccp_send_ack(sk); |
| 693 | } |
| 694 | |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 695 | 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] | 696 | { |
Gerrit Renker | 51c22bb | 2010-08-22 19:41:37 +0000 | [diff] [blame] | 697 | const struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
Andrea Bittau | 60fe62e | 2006-03-20 19:23:32 -0800 | [diff] [blame] | 698 | __be32 x_recv, pinv; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 699 | |
Arnaldo Carvalho de Melo | 59d203f | 2005-09-09 20:01:25 -0300 | [diff] [blame] | 700 | 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] | 701 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 702 | |
Arnaldo Carvalho de Melo | 4fded33 | 2005-08-23 21:51:59 -0700 | [diff] [blame] | 703 | if (dccp_packet_without_ack(skb)) |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 704 | return 0; |
| 705 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 706 | x_recv = htonl(hc->rx_x_recv); |
| 707 | pinv = htonl(hc->rx_pinv); |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 708 | |
Gerrit Renker | a7d13fb | 2010-06-22 01:14:34 +0000 | [diff] [blame] | 709 | if (dccp_insert_option(skb, TFRC_OPT_LOSS_EVENT_RATE, |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 710 | &pinv, sizeof(pinv)) || |
Gerrit Renker | a7d13fb | 2010-06-22 01:14:34 +0000 | [diff] [blame] | 711 | dccp_insert_option(skb, TFRC_OPT_RECEIVE_RATE, |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 712 | &x_recv, sizeof(x_recv))) |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 713 | return -1; |
| 714 | |
| 715 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 716 | } |
| 717 | |
Gerrit Renker | aa1b1ff | 2009-09-12 07:47:01 +0000 | [diff] [blame] | 718 | /** |
| 719 | * ccid3_first_li - Implements [RFC 5348, 6.3.1] |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 720 | * |
| 721 | * Determine the length of the first loss interval via inverse lookup. |
| 722 | * Assume that X_recv can be computed by the throughput equation |
| 723 | * s |
| 724 | * X_recv = -------- |
| 725 | * R * fval |
| 726 | * Find some p such that f(p) = fval; return 1/p (scaled). |
| 727 | */ |
| 728 | static u32 ccid3_first_li(struct sock *sk) |
| 729 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 730 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 731 | u32 x_recv, p, delta; |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 732 | u64 fval; |
| 733 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 734 | if (hc->rx_rtt == 0) { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 735 | DCCP_WARN("No RTT estimate available, using fallback RTT\n"); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 736 | hc->rx_rtt = DCCP_FALLBACK_RTT; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 737 | } |
Gerrit Renker | d20ed95 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 738 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 739 | delta = ktime_to_us(net_timedelta(hc->rx_tstamp_last_feedback)); |
| 740 | x_recv = scaled_div32(hc->rx_bytes_recv, delta); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 741 | if (x_recv == 0) { /* would also trigger divide-by-zero */ |
| 742 | DCCP_WARN("X_recv==0\n"); |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 743 | if (hc->rx_x_recv == 0) { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 744 | DCCP_BUG("stored value of X_recv is zero"); |
| 745 | return ~0U; |
| 746 | } |
Gerrit Renker | 67b67e3 | 2010-08-22 19:41:36 +0000 | [diff] [blame] | 747 | x_recv = hc->rx_x_recv; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 748 | } |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 749 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 750 | fval = scaled_div(hc->rx_s, hc->rx_rtt); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 751 | fval = scaled_div32(fval, x_recv); |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 752 | p = tfrc_calc_x_reverse_lookup(fval); |
| 753 | |
| 754 | ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied " |
| 755 | "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); |
| 756 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 757 | return p == 0 ? ~0U : scaled_div(1, p); |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 758 | } |
| 759 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 760 | static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) |
| 761 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 762 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 763 | enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE; |
Gerrit Renker | 5b5d0e7 | 2008-07-13 11:51:40 +0100 | [diff] [blame] | 764 | const u64 ndp = dccp_sk(sk)->dccps_options_received.dccpor_ndp; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 765 | const bool is_data_packet = dccp_data_packet(skb); |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 766 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 767 | if (unlikely(hc->rx_state == TFRC_RSTATE_NO_DATA)) { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 768 | if (is_data_packet) { |
| 769 | const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; |
| 770 | do_feedback = CCID3_FBACK_INITIAL; |
| 771 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 772 | hc->rx_s = payload; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 773 | /* |
Gerrit Renker | 388d5e9 | 2009-10-05 00:53:11 +0000 | [diff] [blame] | 774 | * Not necessary to update rx_bytes_recv here, |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 775 | * since X_recv = 0 for the first feedback packet (cf. |
| 776 | * RFC 3448, 6.3) -- gerrit |
| 777 | */ |
| 778 | } |
| 779 | goto update_records; |
| 780 | } |
| 781 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 782 | if (tfrc_rx_hist_duplicate(&hc->rx_hist, skb)) |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 783 | return; /* done receiving */ |
| 784 | |
| 785 | if (is_data_packet) { |
| 786 | const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; |
| 787 | /* |
| 788 | * Update moving-average of s and the sum of received payload bytes |
| 789 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 790 | hc->rx_s = tfrc_ewma(hc->rx_s, payload, 9); |
| 791 | hc->rx_bytes_recv += payload; |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 792 | } |
| 793 | |
Gerrit Renker | d20ed95 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 794 | /* |
| 795 | * Perform loss detection and handle pending losses |
| 796 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 797 | if (tfrc_rx_handle_loss(&hc->rx_hist, &hc->rx_li_hist, |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 798 | skb, ndp, ccid3_first_li, sk)) { |
| 799 | do_feedback = CCID3_FBACK_PARAM_CHANGE; |
| 800 | goto done_receiving; |
| 801 | } |
| 802 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 803 | if (tfrc_rx_hist_loss_pending(&hc->rx_hist)) |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 804 | return; /* done receiving */ |
| 805 | |
Gerrit Renker | 88e97a9 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 806 | /* |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 807 | * Handle data packets: RTT sampling and monitoring p |
Gerrit Renker | 88e97a9 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 808 | */ |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 809 | if (unlikely(!is_data_packet)) |
| 810 | goto update_records; |
| 811 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 812 | if (!tfrc_lh_is_initialised(&hc->rx_li_hist)) { |
| 813 | const u32 sample = tfrc_rx_hist_sample_rtt(&hc->rx_hist, skb); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 814 | /* |
| 815 | * Empty loss history: no loss so far, hence p stays 0. |
| 816 | * Sample RTT values, since an RTT estimate is required for the |
| 817 | * computation of p when the first loss occurs; RFC 3448, 6.3.1. |
| 818 | */ |
| 819 | if (sample != 0) |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 820 | hc->rx_rtt = tfrc_ewma(hc->rx_rtt, sample, 9); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 821 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 822 | } else if (tfrc_lh_update_i_mean(&hc->rx_li_hist, skb)) { |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 823 | /* |
| 824 | * Step (3) of [RFC 3448, 6.1]: Recompute I_mean and, if I_mean |
| 825 | * has decreased (resp. p has increased), send feedback now. |
| 826 | */ |
| 827 | do_feedback = CCID3_FBACK_PARAM_CHANGE; |
| 828 | } |
| 829 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 830 | /* |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 831 | * Check if the periodic once-per-RTT feedback is due; RFC 4342, 10.3 |
| 832 | */ |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 833 | if (SUB16(dccp_hdr(skb)->dccph_ccval, hc->rx_last_counter) > 3) |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 834 | do_feedback = CCID3_FBACK_PERIODIC; |
| 835 | |
| 836 | update_records: |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 837 | tfrc_rx_hist_add_packet(&hc->rx_hist, skb, ndp); |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 838 | |
| 839 | done_receiving: |
| 840 | if (do_feedback) |
| 841 | ccid3_hc_rx_send_feedback(sk, skb, do_feedback); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 842 | } |
| 843 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 844 | 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] | 845 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 846 | struct ccid3_hc_rx_sock *hc = ccid_priv(ccid); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 847 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 848 | hc->rx_state = TFRC_RSTATE_NO_DATA; |
| 849 | tfrc_lh_init(&hc->rx_li_hist); |
| 850 | return tfrc_rx_hist_alloc(&hc->rx_hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 851 | } |
| 852 | |
| 853 | static void ccid3_hc_rx_exit(struct sock *sk) |
| 854 | { |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 855 | struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 856 | |
Gerrit Renker | 410e27a | 2008-09-09 13:27:22 +0200 | [diff] [blame] | 857 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM); |
| 858 | |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 859 | tfrc_rx_hist_purge(&hc->rx_hist); |
| 860 | tfrc_lh_cleanup(&hc->rx_li_hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 861 | } |
| 862 | |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 863 | static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) |
| 864 | { |
Gerrit Renker | 51c22bb | 2010-08-22 19:41:37 +0000 | [diff] [blame] | 865 | info->tcpi_ca_state = ccid3_hc_rx_sk(sk)->rx_state; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 866 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; |
Gerrit Renker | 51c22bb | 2010-08-22 19:41:37 +0000 | [diff] [blame] | 867 | info->tcpi_rcv_rtt = ccid3_hc_rx_sk(sk)->rx_rtt; |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 868 | } |
| 869 | |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 870 | static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, |
| 871 | u32 __user *optval, int __user *optlen) |
| 872 | { |
Gerrit Renker | 51c22bb | 2010-08-22 19:41:37 +0000 | [diff] [blame] | 873 | const struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 874 | struct tfrc_rx_info rx_info; |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 875 | const void *val; |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 876 | |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 877 | switch (optname) { |
| 878 | case DCCP_SOCKOPT_CCID_RX_INFO: |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 879 | if (len < sizeof(rx_info)) |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 880 | return -EINVAL; |
Gerrit Renker | 996ccf4 | 2009-10-05 00:53:13 +0000 | [diff] [blame] | 881 | rx_info.tfrcrx_x_recv = hc->rx_x_recv; |
| 882 | rx_info.tfrcrx_rtt = hc->rx_rtt; |
| 883 | rx_info.tfrcrx_p = hc->rx_pinv == 0 ? ~0U : |
| 884 | scaled_div(1, hc->rx_pinv); |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 885 | len = sizeof(rx_info); |
| 886 | val = &rx_info; |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 887 | break; |
| 888 | default: |
| 889 | return -ENOPROTOOPT; |
| 890 | } |
| 891 | |
| 892 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) |
| 893 | return -EFAULT; |
| 894 | |
| 895 | return 0; |
| 896 | } |
| 897 | |
Gerrit Renker | ddebc97 | 2009-01-04 21:42:53 -0800 | [diff] [blame] | 898 | struct ccid_operations ccid3_ops = { |
Ian McDonald | 3dd9a7c | 2006-09-22 14:26:44 +1200 | [diff] [blame] | 899 | .ccid_id = DCCPC_CCID3, |
Gerrit Renker | 84a97b0 | 2007-12-13 23:33:25 -0200 | [diff] [blame] | 900 | .ccid_name = "TCP-Friendly Rate Control", |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 901 | .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] | 902 | .ccid_hc_tx_init = ccid3_hc_tx_init, |
| 903 | .ccid_hc_tx_exit = ccid3_hc_tx_exit, |
| 904 | .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, |
| 905 | .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, |
| 906 | .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 907 | .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 908 | .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] | 909 | .ccid_hc_rx_init = ccid3_hc_rx_init, |
| 910 | .ccid_hc_rx_exit = ccid3_hc_rx_exit, |
| 911 | .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, |
| 912 | .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 913 | .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, |
| 914 | .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 915 | .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt, |
| 916 | .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 917 | }; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 918 | |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 919 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
Gerrit Renker | 4326499 | 2008-08-23 13:28:27 +0200 | [diff] [blame] | 920 | module_param(ccid3_debug, bool, 0644); |
Gerrit Renker | ddebc97 | 2009-01-04 21:42:53 -0800 | [diff] [blame] | 921 | MODULE_PARM_DESC(ccid3_debug, "Enable CCID-3 debug messages"); |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 922 | #endif |