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", |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 59 | }; |
| 60 | |
| 61 | return ccid3_state_names[state]; |
| 62 | } |
| 63 | #endif |
| 64 | |
Arnaldo Carvalho de Melo | c25a18b | 2006-03-20 21:58:56 -0800 | [diff] [blame] | 65 | static void ccid3_hc_tx_set_state(struct sock *sk, |
| 66 | enum ccid3_hc_tx_states state) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 67 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 68 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 69 | enum ccid3_hc_tx_states oldstate = hctx->state; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 70 | |
| 71 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 72 | dccp_role(sk), sk, ccid3_tx_state_name(oldstate), |
| 73 | ccid3_tx_state_name(state)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 74 | WARN_ON(state == oldstate); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 75 | hctx->state = state; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 76 | } |
| 77 | |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 78 | /* |
Gerrit Renker | 6c08b2c | 2007-11-20 17:33:17 -0200 | [diff] [blame] | 79 | * Compute the initial sending rate X_init in the manner of RFC 3390: |
| 80 | * |
| 81 | * X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT |
| 82 | * |
| 83 | * Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis |
| 84 | * (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] | 85 | * For consistency with other parts of the code, X_init is scaled by 2^6. |
| 86 | */ |
| 87 | static inline u64 rfc3390_initial_rate(struct sock *sk) |
| 88 | { |
Gerrit Renker | 6c08b2c | 2007-11-20 17:33:17 -0200 | [diff] [blame] | 89 | const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 90 | const __u32 w_init = clamp_t(__u32, 4380U, 2 * hctx->s, 4 * hctx->s); |
Gerrit Renker | a21f9f9 | 2007-03-20 15:12:10 -0300 | [diff] [blame] | 91 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 92 | return scaled_div(w_init << 6, hctx->rtt); |
Gerrit Renker | a21f9f9 | 2007-03-20 15:12:10 -0300 | [diff] [blame] | 93 | } |
| 94 | |
Gerrit Renker | de6f2b5 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 95 | /** |
| 96 | * ccid3_update_send_interval - Calculate new t_ipi = s / X_inst |
| 97 | * This respects the granularity of X_inst (64 * bytes/second). |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 98 | */ |
Ilpo Järvinen | c4e18da | 2008-01-05 23:13:58 -0800 | [diff] [blame] | 99 | static 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] | 100 | { |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 101 | hctx->t_ipi = scaled_div32(((u64)hctx->s) << 6, hctx->x); |
Gerrit Renker | 17893bc | 2006-11-27 20:31:33 -0200 | [diff] [blame] | 102 | |
Gerrit Renker | de6f2b5 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 103 | ccid3_pr_debug("t_ipi=%u, s=%u, X=%u\n", hctx->t_ipi, |
| 104 | hctx->s, (unsigned)(hctx->x >> 6)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 105 | } |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 106 | |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 107 | static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hctx, ktime_t now) |
| 108 | { |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 109 | u32 delta = ktime_us_delta(now, hctx->t_last_win_count); |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 110 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 111 | return delta / hctx->rtt; |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 112 | } |
| 113 | |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 114 | /** |
| 115 | * ccid3_hc_tx_update_x - Update allowed sending rate X |
| 116 | * @stamp: most recent time if available - can be left NULL. |
| 117 | * This function tracks draft rfc3448bis, check there for latest details. |
Gerrit Renker | 5c3fbb6 | 2006-12-03 14:50:56 -0200 | [diff] [blame] | 118 | * |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 119 | * Note: X and X_recv are both stored in units of 64 * bytes/second, to support |
| 120 | * fine-grained resolution of sending rates. This requires scaling by 2^6 |
| 121 | * throughout the code. Only X_calc is unscaled (in bytes/second). |
| 122 | * |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 123 | */ |
Gerrit Renker | aa97efd | 2007-09-25 22:39:16 -0700 | [diff] [blame] | 124 | 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] | 125 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 126 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 127 | u64 min_rate = 2 * hctx->x_recv; |
| 128 | const u64 old_x = hctx->x; |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 129 | ktime_t now = stamp ? *stamp : ktime_get_real(); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 130 | |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 131 | /* |
| 132 | * Handle IDLE periods: do not reduce below RFC3390 initial sending rate |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 133 | * when idling [RFC 4342, 5.1]. Definition of idling is from rfc3448bis: |
| 134 | * 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] | 135 | * For consistency with X and X_recv, min_rate is also scaled by 2^6. |
| 136 | */ |
Gerrit Renker | a5358fd | 2007-11-20 18:01:59 -0200 | [diff] [blame] | 137 | if (ccid3_hc_tx_idle_rtt(hctx, now) >= 2) { |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 138 | min_rate = rfc3390_initial_rate(sk); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 139 | min_rate = max(min_rate, 2 * hctx->x_recv); |
Gerrit Renker | 0c150ef | 2007-03-20 15:19:07 -0300 | [diff] [blame] | 140 | } |
| 141 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 142 | if (hctx->p > 0) { |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 143 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 144 | hctx->x = min(((u64)hctx->x_calc) << 6, min_rate); |
| 145 | hctx->x = max(hctx->x, (((u64)hctx->s) << 6) / TFRC_T_MBI); |
Arnaldo Carvalho de Melo | b6ee3d4 | 2005-08-27 18:18:18 -0300 | [diff] [blame] | 146 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 147 | } else if (ktime_us_delta(now, hctx->t_ld) - (s64)hctx->rtt >= 0) { |
Gerrit Renker | 1a21e49 | 2006-12-10 00:02:12 -0200 | [diff] [blame] | 148 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 149 | hctx->x = min(2 * hctx->x, min_rate); |
| 150 | hctx->x = max(hctx->x, |
| 151 | scaled_div(((u64)hctx->s) << 6, hctx->rtt)); |
| 152 | hctx->t_ld = now; |
Gerrit Renker | ff58629 | 2006-12-10 00:00:14 -0200 | [diff] [blame] | 153 | } |
Gerrit Renker | a79ef76 | 2006-11-28 19:51:42 -0200 | [diff] [blame] | 154 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 155 | if (hctx->x != old_x) { |
Gerrit Renker | 1761f7d | 2007-03-20 15:04:30 -0300 | [diff] [blame] | 156 | ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, " |
| 157 | "X_recv=%u\n", (unsigned)(old_x >> 6), |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 158 | (unsigned)(hctx->x >> 6), hctx->x_calc, |
| 159 | (unsigned)(hctx->x_recv >> 6)); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 160 | |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 161 | ccid3_update_send_interval(hctx); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 162 | } |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 163 | } |
| 164 | |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 165 | /* |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 166 | * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1) |
| 167 | * @len: DCCP packet payload size in bytes |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 168 | */ |
| 169 | static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len) |
| 170 | { |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 171 | const u16 old_s = hctx->s; |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 172 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 173 | hctx->s = tfrc_ewma(hctx->s, len, 9); |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 174 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 175 | if (hctx->s != old_s) |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 176 | ccid3_update_send_interval(hctx); |
Gerrit Renker | 78ad713 | 2006-11-28 19:22:33 -0200 | [diff] [blame] | 177 | } |
| 178 | |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 179 | /* |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 180 | * Update Window Counter using the algorithm from [RFC 4342, 8.1]. |
Gerrit Renker | 825de27 | 2008-05-27 06:33:54 -0700 | [diff] [blame] | 181 | * As elsewhere, RTT > 0 is assumed by using dccp_sample_rtt(). |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 182 | */ |
| 183 | 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] | 184 | ktime_t now) |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 185 | { |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 186 | u32 delta = ktime_us_delta(now, hctx->t_last_win_count), |
| 187 | quarter_rtts = (4 * delta) / hctx->rtt; |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 188 | |
| 189 | if (quarter_rtts > 0) { |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 190 | hctx->t_last_win_count = now; |
| 191 | hctx->last_win_count += min(quarter_rtts, 5U); |
| 192 | hctx->last_win_count &= 0xF; /* mod 16 */ |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 193 | } |
| 194 | } |
| 195 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 196 | static void ccid3_hc_tx_no_feedback_timer(unsigned long data) |
| 197 | { |
| 198 | struct sock *sk = (struct sock *)data; |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 199 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 2a1fda6 | 2006-11-28 18:34:34 -0200 | [diff] [blame] | 200 | unsigned long t_nfb = USEC_PER_SEC / 5; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 201 | |
| 202 | bh_lock_sock(sk); |
| 203 | if (sock_owned_by_user(sk)) { |
| 204 | /* Try again later. */ |
| 205 | /* XXX: set some sensible MIB */ |
Gerrit Renker | 48e03ee | 2006-11-27 20:29:27 -0200 | [diff] [blame] | 206 | goto restart_timer; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 207 | } |
| 208 | |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 209 | ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk, |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 210 | ccid3_tx_state_name(hctx->state)); |
Gerrit Renker | a967241 | 2006-12-10 00:14:12 -0200 | [diff] [blame] | 211 | |
Gerrit Renker | d0995e6 | 2008-09-04 07:30:19 +0200 | [diff] [blame^] | 212 | /* Ignore and do not restart after leaving the established state */ |
| 213 | if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN)) |
| 214 | goto out; |
| 215 | |
| 216 | /* Reset feedback state to "no feedback received" */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 217 | if (hctx->state == TFRC_SSTATE_FBACK) |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 218 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 219 | |
| 220 | /* |
| 221 | * Determine new allowed sending rate X as per draft rfc3448bis-00, 4.4 |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 222 | * 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] | 223 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 224 | if (hctx->t_rto == 0 || hctx->p == 0) { |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 225 | |
| 226 | /* halve send rate directly */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 227 | hctx->x = max(hctx->x / 2, (((u64)hctx->s) << 6) / TFRC_T_MBI); |
Gerrit Renker | 1266ade | 2007-03-20 14:56:11 -0300 | [diff] [blame] | 228 | ccid3_update_send_interval(hctx); |
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 | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 240 | BUG_ON(hctx->p && !hctx->x_calc); |
Gerrit Renker | a79ef76 | 2006-11-28 19:51:42 -0200 | [diff] [blame] | 241 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 242 | if (hctx->x_calc > (hctx->x_recv >> 5)) |
| 243 | hctx->x_recv = |
| 244 | max(hctx->x_recv / 2, |
| 245 | (((__u64)hctx->s) << 6) / (2 * TFRC_T_MBI)); |
Gerrit Renker | 52515e7 | 2007-12-17 12:57:43 -0200 | [diff] [blame] | 246 | else { |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 247 | hctx->x_recv = hctx->x_calc; |
| 248 | hctx->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 | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 253 | (unsigned long long)hctx->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 | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 259 | if (unlikely(hctx->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 | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 262 | t_nfb = max(hctx->t_rto, 2 * hctx->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 | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 265 | sk_reset_timer(sk, &hctx->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 | 7da7f45 | 2006-11-27 12:26:03 -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 |
| 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); |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 281 | struct ccid3_hc_tx_sock *hctx = 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 | d0995e6 | 2008-09-04 07:30:19 +0200 | [diff] [blame^] | 293 | if (hctx->state == TFRC_SSTATE_NO_SENT) { |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 294 | sk_reset_timer(sk, &hctx->no_feedback_timer, (jiffies + |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 295 | usecs_to_jiffies(TFRC_INITIAL_TIMEOUT))); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 296 | hctx->last_win_count = 0; |
| 297 | hctx->t_last_win_count = now; |
Gerrit Renker | 90feeb9 | 2006-11-27 12:13:38 -0200 | [diff] [blame] | 298 | |
| 299 | /* Set t_0 for initial packet */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 300 | hctx->t_nom = now; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 301 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 302 | hctx->s = skb->len; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 303 | |
| 304 | /* |
| 305 | * Use initial RTT sample when available: recommended by erratum |
| 306 | * to RFC 4342. This implements the initialisation procedure of |
| 307 | * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6. |
| 308 | */ |
| 309 | if (dp->dccps_syn_rtt) { |
| 310 | ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 311 | hctx->rtt = dp->dccps_syn_rtt; |
| 312 | hctx->x = rfc3390_initial_rate(sk); |
| 313 | hctx->t_ld = now; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 314 | } else { |
Gerrit Renker | 3294f20 | 2008-06-11 11:19:09 +0100 | [diff] [blame] | 315 | /* |
| 316 | * Sender does not have RTT sample: |
| 317 | * - set fallback RTT (RFC 4340, 3.4) since a RTT value |
| 318 | * is needed in several parts (e.g. window counter); |
| 319 | * - set sending rate X_pps = 1pps as per RFC 3448, 4.2. |
| 320 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 321 | hctx->rtt = DCCP_FALLBACK_RTT; |
| 322 | hctx->x = hctx->s; |
| 323 | hctx->x <<= 6; |
Gerrit Renker | 30833ff | 2007-03-20 15:31:56 -0300 | [diff] [blame] | 324 | } |
| 325 | ccid3_update_send_interval(hctx); |
| 326 | |
| 327 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); |
Gerrit Renker | d0995e6 | 2008-09-04 07:30:19 +0200 | [diff] [blame^] | 328 | |
| 329 | } else { |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 330 | delay = ktime_us_delta(hctx->t_nom, now); |
Ian McDonald | 8699be7 | 2007-03-20 14:49:20 -0300 | [diff] [blame] | 331 | ccid3_pr_debug("delay=%ld\n", (long)delay); |
Gerrit Renker | 91cf5a1 | 2006-11-27 12:25:10 -0200 | [diff] [blame] | 332 | /* |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 333 | * Scheduling of packet transmissions [RFC 3448, 4.6] |
Gerrit Renker | 91cf5a1 | 2006-11-27 12:25:10 -0200 | [diff] [blame] | 334 | * |
| 335 | * if (t_now > t_nom - delta) |
| 336 | * // send the packet now |
| 337 | * else |
| 338 | * // send the packet in (t_nom - t_now) milliseconds. |
| 339 | */ |
Gerrit Renker | de6f2b5 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 340 | if (delay >= TFRC_T_DELTA) |
| 341 | return (u32)delay / USEC_PER_MSEC; |
Gerrit Renker | 9f8681d | 2006-12-10 00:07:37 -0200 | [diff] [blame] | 342 | |
Gerrit Renker | 8132da4 | 2007-06-16 13:34:02 -0300 | [diff] [blame] | 343 | ccid3_hc_tx_update_win_count(hctx, now); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 344 | } |
| 345 | |
Gerrit Renker | 7da7f45 | 2006-11-27 12:26:03 -0200 | [diff] [blame] | 346 | /* prepare to send now (add options etc.) */ |
| 347 | dp->dccps_hc_tx_insert_options = 1; |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 348 | DCCP_SKB_CB(skb)->dccpd_ccval = hctx->last_win_count; |
Gerrit Renker | e312d10 | 2006-12-10 00:08:09 -0200 | [diff] [blame] | 349 | |
| 350 | /* set the nominal send time for the next following packet */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 351 | hctx->t_nom = ktime_add_us(hctx->t_nom, hctx->t_ipi); |
Gerrit Renker | 7da7f45 | 2006-11-27 12:26:03 -0200 | [diff] [blame] | 352 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 353 | } |
| 354 | |
Gerrit Renker | c506d91 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 355 | static void ccid3_hc_tx_packet_sent(struct sock *sk, unsigned int len) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 356 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 357 | 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] | 358 | |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 359 | ccid3_hc_tx_update_s(hctx, len); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 360 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 361 | if (tfrc_tx_hist_add(&hctx->hist, dccp_sk(sk)->dccps_gss)) |
Gerrit Renker | c5a1ae9 | 2006-12-10 00:09:21 -0200 | [diff] [blame] | 362 | DCCP_CRIT("packet history - out of memory!"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 363 | } |
| 364 | |
| 365 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) |
| 366 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 367 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 63b3a73 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 368 | struct tfrc_tx_hist_entry *acked; |
Arnaldo Carvalho de Melo | 0740d49 | 2007-08-19 17:18:13 -0700 | [diff] [blame] | 369 | ktime_t now; |
Gerrit Renker | 2a1fda6 | 2006-11-28 18:34:34 -0200 | [diff] [blame] | 370 | unsigned long t_nfb; |
Gerrit Renker | ce177ae | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 371 | u32 r_sample; |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 372 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 373 | /* we are only interested in ACKs */ |
| 374 | if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || |
| 375 | DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) |
| 376 | return; |
Gerrit Renker | 63b3a73 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 377 | /* |
| 378 | * Locate the acknowledged packet in the TX history. |
| 379 | * |
| 380 | * Returning "entry not found" here can for instance happen when |
| 381 | * - the host has not sent out anything (e.g. a passive server), |
| 382 | * - the Ack is outdated (packet with higher Ack number was received), |
| 383 | * - it is a bogus Ack (for a packet not sent on this connection). |
| 384 | */ |
| 385 | acked = tfrc_tx_hist_find_entry(hctx->hist, dccp_hdr_ack_seq(skb)); |
| 386 | if (acked == NULL) |
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 | /* For the sake of RTT sampling, ignore/remove all older entries */ |
| 389 | tfrc_tx_hist_purge(&acked->next); |
| 390 | |
| 391 | /* Update the moving average for the RTT estimate (RFC 3448, 4.3) */ |
| 392 | now = ktime_get_real(); |
| 393 | r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, acked->stamp)); |
| 394 | hctx->rtt = tfrc_ewma(hctx->rtt, r_sample, 9); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 395 | |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 396 | /* |
| 397 | * Update allowed sending rate X as per draft rfc3448bis-00, 4.2/3 |
| 398 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 399 | if (hctx->state == TFRC_SSTATE_NO_FBACK) { |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 400 | ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 401 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 402 | if (hctx->t_rto == 0) { |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 403 | /* |
| 404 | * Initial feedback packet: Larger Initial Windows (4.2) |
| 405 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 406 | hctx->x = rfc3390_initial_rate(sk); |
| 407 | hctx->t_ld = now; |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 408 | |
| 409 | ccid3_update_send_interval(hctx); |
| 410 | |
| 411 | goto done_computing_x; |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 412 | } else if (hctx->p == 0) { |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 413 | /* |
| 414 | * First feedback after nofeedback timer expiry (4.3) |
| 415 | */ |
| 416 | goto done_computing_x; |
| 417 | } |
| 418 | } |
| 419 | |
| 420 | /* Update sending rate (step 4 of [RFC 3448, 4.3]) */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 421 | if (hctx->p > 0) |
| 422 | hctx->x_calc = tfrc_calc_x(hctx->s, hctx->rtt, hctx->p); |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 423 | ccid3_hc_tx_update_x(sk, &now); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 424 | |
Gerrit Renker | d8d1252 | 2007-12-17 12:48:47 -0200 | [diff] [blame] | 425 | done_computing_x: |
| 426 | ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, " |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 427 | "p=%u, X_calc=%u, X_recv=%u, X=%u\n", |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 428 | dccp_role(sk), sk, hctx->rtt, r_sample, |
| 429 | hctx->s, hctx->p, hctx->x_calc, |
| 430 | (unsigned)(hctx->x_recv >> 6), |
| 431 | (unsigned)(hctx->x >> 6)); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 432 | |
| 433 | /* unschedule no feedback timer */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 434 | sk_stop_timer(sk, &hctx->no_feedback_timer); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 435 | |
| 436 | /* |
| 437 | * As we have calculated new ipi, delta, t_nom it is possible |
| 438 | * that we now can send a packet, so wake up dccp_wait_for_ccid |
| 439 | */ |
| 440 | sk->sk_write_space(sk); |
| 441 | |
| 442 | /* |
| 443 | * Update timeout interval for the nofeedback timer. |
| 444 | * We use a configuration option to increase the lower bound. |
| 445 | * This can help avoid triggering the nofeedback timer too |
| 446 | * often ('spinning') on LANs with small RTTs. |
| 447 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 448 | hctx->t_rto = max_t(u32, 4 * hctx->rtt, (CONFIG_IP_DCCP_CCID3_RTO * |
| 449 | (USEC_PER_SEC / 1000))); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 450 | /* |
| 451 | * Schedule no feedback timer to expire in |
| 452 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
| 453 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 454 | t_nfb = max(hctx->t_rto, 2 * hctx->t_ipi); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 455 | |
| 456 | ccid3_pr_debug("%s(%p), Scheduled no feedback timer to " |
| 457 | "expire in %lu jiffies (%luus)\n", |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 458 | dccp_role(sk), sk, usecs_to_jiffies(t_nfb), t_nfb); |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 459 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 460 | sk_reset_timer(sk, &hctx->no_feedback_timer, |
Gerrit Renker | 5bd370a | 2007-12-17 10:25:06 -0200 | [diff] [blame] | 461 | jiffies + usecs_to_jiffies(t_nfb)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 462 | } |
| 463 | |
Gerrit Renker | 3306c78 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 464 | static int ccid3_hc_tx_parse_options(struct sock *sk, u8 packet_type, |
| 465 | u8 option, u8 *optval, u8 optlen) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 466 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 467 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 76fd1e8 | 2007-10-24 10:46:58 -0200 | [diff] [blame] | 468 | __be32 opt_val; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 469 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 470 | switch (option) { |
Gerrit Renker | 47a61e7 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 471 | case TFRC_OPT_RECEIVE_RATE: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 472 | case TFRC_OPT_LOSS_EVENT_RATE: |
Gerrit Renker | 3306c78 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 473 | /* Must be ignored on Data packets, cf. RFC 4342 8.3 and 8.5 */ |
| 474 | if (packet_type == DCCP_PKT_DATA) |
| 475 | break; |
| 476 | if (unlikely(optlen != 4)) { |
Gerrit Renker | 47a61e7 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 477 | DCCP_WARN("%s(%p), invalid len %d for %u\n", |
Gerrit Renker | 3306c78 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 478 | dccp_role(sk), sk, optlen, option); |
Gerrit Renker | 47a61e7 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 479 | return -EINVAL; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 480 | } |
Gerrit Renker | 3306c78 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 481 | opt_val = ntohl(get_unaligned((__be32 *)optval)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 482 | |
Gerrit Renker | 47a61e7 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 483 | if (option == TFRC_OPT_RECEIVE_RATE) { |
Gerrit Renker | ce177ae | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 484 | /* Receive Rate is kept in units of 64 bytes/second */ |
| 485 | hctx->x_recv = opt_val; |
| 486 | hctx->x_recv <<= 6; |
| 487 | |
Gerrit Renker | 47a61e7 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 488 | ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n", |
| 489 | dccp_role(sk), sk, opt_val); |
| 490 | } else { |
Gerrit Renker | ce177ae | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 491 | /* Update the fixpoint Loss Event Rate fraction */ |
| 492 | hctx->p = tfrc_invert_loss_event_rate(opt_val); |
| 493 | |
Gerrit Renker | 47a61e7 | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 494 | ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n", |
| 495 | dccp_role(sk), sk, opt_val); |
| 496 | } |
| 497 | } |
| 498 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 499 | } |
| 500 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 501 | 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] | 502 | { |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 503 | struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 504 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 505 | hctx->state = TFRC_SSTATE_NO_SENT; |
| 506 | hctx->hist = NULL; |
| 507 | setup_timer(&hctx->no_feedback_timer, |
| 508 | ccid3_hc_tx_no_feedback_timer, (unsigned long)sk); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 509 | return 0; |
| 510 | } |
| 511 | |
| 512 | static void ccid3_hc_tx_exit(struct sock *sk) |
| 513 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 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 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 516 | sk_stop_timer(sk, &hctx->no_feedback_timer); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 517 | tfrc_tx_hist_purge(&hctx->hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 518 | } |
| 519 | |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 520 | static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) |
| 521 | { |
Gerrit Renker | b2e317f | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 522 | info->tcpi_rto = ccid3_hc_tx_sk(sk)->t_rto; |
| 523 | info->tcpi_rtt = ccid3_hc_tx_sk(sk)->rtt; |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 524 | } |
| 525 | |
| 526 | static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, |
| 527 | u32 __user *optval, int __user *optlen) |
| 528 | { |
Gerrit Renker | b2e317f | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 529 | const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 530 | struct tfrc_tx_info tfrc; |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 531 | const void *val; |
| 532 | |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 533 | switch (optname) { |
| 534 | case DCCP_SOCKOPT_CCID_TX_INFO: |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 535 | if (len < sizeof(tfrc)) |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 536 | return -EINVAL; |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 537 | tfrc.tfrctx_x = hctx->x; |
| 538 | tfrc.tfrctx_x_recv = hctx->x_recv; |
| 539 | tfrc.tfrctx_x_calc = hctx->x_calc; |
| 540 | tfrc.tfrctx_rtt = hctx->rtt; |
| 541 | tfrc.tfrctx_p = hctx->p; |
| 542 | tfrc.tfrctx_rto = hctx->t_rto; |
| 543 | tfrc.tfrctx_ipi = hctx->t_ipi; |
| 544 | len = sizeof(tfrc); |
| 545 | val = &tfrc; |
Gerrit Renker | 9bf1747 | 2007-03-20 13:11:24 -0300 | [diff] [blame] | 546 | break; |
| 547 | default: |
| 548 | return -ENOPROTOOPT; |
| 549 | } |
| 550 | |
| 551 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) |
| 552 | return -EFAULT; |
| 553 | |
| 554 | return 0; |
| 555 | } |
| 556 | |
| 557 | /* |
| 558 | * Receiver Half-Connection Routines |
| 559 | */ |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 560 | |
| 561 | /* CCID3 feedback types */ |
| 562 | enum ccid3_fback_type { |
| 563 | CCID3_FBACK_NONE = 0, |
| 564 | CCID3_FBACK_INITIAL, |
| 565 | CCID3_FBACK_PERIODIC, |
| 566 | CCID3_FBACK_PARAM_CHANGE |
| 567 | }; |
| 568 | |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 569 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 570 | static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) |
| 571 | { |
| 572 | static char *ccid3_rx_state_names[] = { |
| 573 | [TFRC_RSTATE_NO_DATA] = "NO_DATA", |
| 574 | [TFRC_RSTATE_DATA] = "DATA", |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 575 | }; |
| 576 | |
| 577 | return ccid3_rx_state_names[state]; |
| 578 | } |
| 579 | #endif |
| 580 | |
Arnaldo Carvalho de Melo | c25a18b | 2006-03-20 21:58:56 -0800 | [diff] [blame] | 581 | static void ccid3_hc_rx_set_state(struct sock *sk, |
| 582 | enum ccid3_hc_rx_states state) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 583 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 584 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 585 | enum ccid3_hc_rx_states oldstate = hcrx->state; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 586 | |
| 587 | ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 588 | dccp_role(sk), sk, ccid3_rx_state_name(oldstate), |
| 589 | ccid3_rx_state_name(state)); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 590 | WARN_ON(state == oldstate); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 591 | hcrx->state = state; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 592 | } |
| 593 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 594 | static void ccid3_hc_rx_send_feedback(struct sock *sk, |
| 595 | const struct sk_buff *skb, |
| 596 | enum ccid3_fback_type fbtype) |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 597 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 598 | 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] | 599 | struct dccp_sock *dp = dccp_sk(sk); |
Gerrit Renker | d0995e6 | 2008-09-04 07:30:19 +0200 | [diff] [blame^] | 600 | ktime_t now = ktime_get_real(); |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 601 | s64 delta = 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 602 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 603 | switch (fbtype) { |
| 604 | case CCID3_FBACK_INITIAL: |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 605 | hcrx->x_recv = 0; |
| 606 | hcrx->p_inverse = ~0U; /* see RFC 4342, 8.5 */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 607 | break; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 608 | case CCID3_FBACK_PARAM_CHANGE: |
| 609 | /* |
| 610 | * When parameters change (new loss or p > p_prev), we do not |
| 611 | * have a reliable estimate for R_m of [RFC 3448, 6.2] and so |
| 612 | * need to reuse the previous value of X_recv. However, when |
| 613 | * X_recv was 0 (due to early loss), this would kill X down to |
| 614 | * s/t_mbi (i.e. one packet in 64 seconds). |
| 615 | * To avoid such drastic reduction, we approximate X_recv as |
| 616 | * the number of bytes since last feedback. |
| 617 | * This is a safe fallback, since X is bounded above by X_calc. |
| 618 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 619 | if (hcrx->x_recv > 0) |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 620 | break; |
| 621 | /* fall through */ |
| 622 | case CCID3_FBACK_PERIODIC: |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 623 | delta = ktime_us_delta(now, hcrx->tstamp_last_feedback); |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 624 | if (delta <= 0) |
| 625 | DCCP_BUG("delta (%ld) <= 0", (long)delta); |
| 626 | else |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 627 | hcrx->x_recv = scaled_div32(hcrx->bytes_recv, delta); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 628 | break; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 629 | default: |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 630 | return; |
| 631 | } |
| 632 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 633 | ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", |
| 634 | (long)delta, hcrx->x_recv, hcrx->p_inverse); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 635 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 636 | hcrx->tstamp_last_feedback = now; |
| 637 | hcrx->last_counter = dccp_hdr(skb)->dccph_ccval; |
| 638 | hcrx->bytes_recv = 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 639 | |
Arnaldo Carvalho de Melo | 507d37c | 2005-09-09 02:30:07 -0300 | [diff] [blame] | 640 | dp->dccps_hc_rx_insert_options = 1; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 641 | dccp_send_ack(sk); |
| 642 | } |
| 643 | |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 644 | 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] | 645 | { |
Gerrit Renker | b2e317f | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 646 | const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
Andrea Bittau | 60fe62e | 2006-03-20 19:23:32 -0800 | [diff] [blame] | 647 | __be32 x_recv, pinv; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 648 | |
Arnaldo Carvalho de Melo | 59d203f | 2005-09-09 20:01:25 -0300 | [diff] [blame] | 649 | 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] | 650 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 651 | |
Arnaldo Carvalho de Melo | 4fded33 | 2005-08-23 21:51:59 -0700 | [diff] [blame] | 652 | if (dccp_packet_without_ack(skb)) |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 653 | return 0; |
| 654 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 655 | x_recv = htonl(hcrx->x_recv); |
| 656 | pinv = htonl(hcrx->p_inverse); |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 657 | |
Gerrit Renker | 385ac2e | 2007-12-08 16:26:59 -0200 | [diff] [blame] | 658 | 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] | 659 | &pinv, sizeof(pinv)) || |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 660 | dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE, |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 661 | &x_recv, sizeof(x_recv))) |
Arnaldo Carvalho de Melo | 2d0817d | 2006-03-20 22:32:06 -0800 | [diff] [blame] | 662 | return -1; |
| 663 | |
| 664 | return 0; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 665 | } |
| 666 | |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 667 | /** ccid3_first_li - Implements [RFC 3448, 6.3.1] |
| 668 | * |
| 669 | * Determine the length of the first loss interval via inverse lookup. |
| 670 | * Assume that X_recv can be computed by the throughput equation |
| 671 | * s |
| 672 | * X_recv = -------- |
| 673 | * R * fval |
| 674 | * Find some p such that f(p) = fval; return 1/p (scaled). |
| 675 | */ |
| 676 | static u32 ccid3_first_li(struct sock *sk) |
| 677 | { |
| 678 | struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
| 679 | u32 x_recv, p, delta; |
| 680 | u64 fval; |
| 681 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 682 | if (hcrx->rtt == 0) { |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 683 | DCCP_WARN("No RTT estimate available, using fallback RTT\n"); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 684 | hcrx->rtt = DCCP_FALLBACK_RTT; |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 685 | } |
| 686 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 687 | delta = ktime_to_us(net_timedelta(hcrx->tstamp_last_feedback)); |
| 688 | x_recv = scaled_div32(hcrx->bytes_recv, delta); |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 689 | if (x_recv == 0) { /* would also trigger divide-by-zero */ |
| 690 | DCCP_WARN("X_recv==0\n"); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 691 | if (hcrx->x_recv == 0) { |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 692 | DCCP_BUG("stored value of X_recv is zero"); |
| 693 | return ~0U; |
| 694 | } |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 695 | x_recv = hcrx->x_recv; |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 696 | } |
| 697 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 698 | fval = scaled_div(hcrx->s, hcrx->rtt); |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 699 | fval = scaled_div32(fval, x_recv); |
| 700 | p = tfrc_calc_x_reverse_lookup(fval); |
| 701 | |
| 702 | ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied " |
| 703 | "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); |
| 704 | |
| 705 | return p == 0 ? ~0U : scaled_div(1, p); |
| 706 | } |
| 707 | |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 708 | static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) |
| 709 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 710 | 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] | 711 | enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE; |
Gerrit Renker | 5b5d0e7 | 2008-07-13 11:51:40 +0100 | [diff] [blame] | 712 | 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] | 713 | const bool is_data_packet = dccp_data_packet(skb); |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 714 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 715 | if (unlikely(hcrx->state == TFRC_RSTATE_NO_DATA)) { |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 716 | if (is_data_packet) { |
| 717 | const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; |
| 718 | do_feedback = CCID3_FBACK_INITIAL; |
| 719 | ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 720 | hcrx->s = payload; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 721 | /* |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 722 | * Not necessary to update bytes_recv here, |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 723 | * since X_recv = 0 for the first feedback packet (cf. |
| 724 | * RFC 3448, 6.3) -- gerrit |
| 725 | */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 726 | } |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 727 | goto update_records; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 728 | } |
| 729 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 730 | if (tfrc_rx_hist_duplicate(&hcrx->hist, skb)) |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 731 | return; /* done receiving */ |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 732 | |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 733 | if (is_data_packet) { |
| 734 | const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; |
| 735 | /* |
| 736 | * Update moving-average of s and the sum of received payload bytes |
| 737 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 738 | hcrx->s = tfrc_ewma(hcrx->s, payload, 9); |
| 739 | hcrx->bytes_recv += payload; |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 740 | } |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 741 | |
| 742 | /* |
Gerrit Renker | b552c62 | 2008-07-13 11:51:40 +0100 | [diff] [blame] | 743 | * Perform loss detection and handle pending losses |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 744 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 745 | if (tfrc_rx_handle_loss(&hcrx->hist, &hcrx->li_hist, |
Gerrit Renker | b552c62 | 2008-07-13 11:51:40 +0100 | [diff] [blame] | 746 | skb, ndp, ccid3_first_li, sk)) { |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 747 | do_feedback = CCID3_FBACK_PARAM_CHANGE; |
| 748 | goto done_receiving; |
| 749 | } |
| 750 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 751 | if (tfrc_rx_hist_loss_pending(&hcrx->hist)) |
Gerrit Renker | b552c62 | 2008-07-13 11:51:40 +0100 | [diff] [blame] | 752 | return; /* done receiving */ |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 753 | |
| 754 | /* |
| 755 | * Handle data packets: RTT sampling and monitoring p |
| 756 | */ |
| 757 | if (unlikely(!is_data_packet)) |
| 758 | goto update_records; |
| 759 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 760 | if (!tfrc_lh_is_initialised(&hcrx->li_hist)) { |
| 761 | const u32 sample = tfrc_rx_hist_sample_rtt(&hcrx->hist, skb); |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 762 | /* |
| 763 | * Empty loss history: no loss so far, hence p stays 0. |
| 764 | * Sample RTT values, since an RTT estimate is required for the |
| 765 | * computation of p when the first loss occurs; RFC 3448, 6.3.1. |
| 766 | */ |
| 767 | if (sample != 0) |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 768 | hcrx->rtt = tfrc_ewma(hcrx->rtt, sample, 9); |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 769 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 770 | } else if (tfrc_lh_update_i_mean(&hcrx->li_hist, skb)) { |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 771 | /* |
| 772 | * Step (3) of [RFC 3448, 6.1]: Recompute I_mean and, if I_mean |
| 773 | * has decreased (resp. p has increased), send feedback now. |
| 774 | */ |
| 775 | do_feedback = CCID3_FBACK_PARAM_CHANGE; |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 776 | } |
| 777 | |
| 778 | /* |
| 779 | * Check if the periodic once-per-RTT feedback is due; RFC 4342, 10.3 |
| 780 | */ |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 781 | if (SUB16(dccp_hdr(skb)->dccph_ccval, hcrx->last_counter) > 3) |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 782 | do_feedback = CCID3_FBACK_PERIODIC; |
| 783 | |
| 784 | update_records: |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 785 | tfrc_rx_hist_add_packet(&hcrx->hist, skb, ndp); |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 786 | |
Gerrit Renker | 954c2db | 2007-12-12 14:06:14 -0200 | [diff] [blame] | 787 | done_receiving: |
Arnaldo Carvalho de Melo | b84a218 | 2007-12-06 13:18:11 -0200 | [diff] [blame] | 788 | if (do_feedback) |
| 789 | ccid3_hc_rx_send_feedback(sk, skb, do_feedback); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 790 | } |
| 791 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 792 | 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] | 793 | { |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 794 | struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 795 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 796 | hcrx->state = TFRC_RSTATE_NO_DATA; |
| 797 | tfrc_lh_init(&hcrx->li_hist); |
| 798 | return tfrc_rx_hist_alloc(&hcrx->hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 799 | } |
| 800 | |
| 801 | static void ccid3_hc_rx_exit(struct sock *sk) |
| 802 | { |
Arnaldo Carvalho de Melo | 59725dc | 2005-09-09 02:40:58 -0300 | [diff] [blame] | 803 | 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] | 804 | |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 805 | tfrc_rx_hist_purge(&hcrx->hist); |
| 806 | tfrc_lh_cleanup(&hcrx->li_hist); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 807 | } |
| 808 | |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 809 | static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) |
| 810 | { |
Gerrit Renker | b2e317f | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 811 | info->tcpi_ca_state = ccid3_hc_rx_sk(sk)->state; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 812 | info->tcpi_options |= TCPI_OPT_TIMESTAMPS; |
Gerrit Renker | b2e317f | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 813 | info->tcpi_rcv_rtt = ccid3_hc_rx_sk(sk)->rtt; |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 814 | } |
| 815 | |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 816 | static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, |
| 817 | u32 __user *optval, int __user *optlen) |
| 818 | { |
Gerrit Renker | b2e317f | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 819 | const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 820 | struct tfrc_rx_info rx_info; |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 821 | const void *val; |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 822 | |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 823 | switch (optname) { |
| 824 | case DCCP_SOCKOPT_CCID_RX_INFO: |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 825 | if (len < sizeof(rx_info)) |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 826 | return -EINVAL; |
Gerrit Renker | 842d1ef | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 827 | rx_info.tfrcrx_x_recv = hcrx->x_recv; |
| 828 | rx_info.tfrcrx_rtt = hcrx->rtt; |
Gerrit Renker | 535c55d | 2008-09-04 07:30:19 +0200 | [diff] [blame] | 829 | rx_info.tfrcrx_p = tfrc_invert_loss_event_rate(hcrx->p_inverse); |
Gerrit Renker | 8e138e7 | 2007-12-17 10:07:44 -0200 | [diff] [blame] | 830 | len = sizeof(rx_info); |
| 831 | val = &rx_info; |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 832 | break; |
| 833 | default: |
| 834 | return -ENOPROTOOPT; |
| 835 | } |
| 836 | |
| 837 | if (put_user(len, optlen) || copy_to_user(optval, val, len)) |
| 838 | return -EFAULT; |
| 839 | |
| 840 | return 0; |
| 841 | } |
| 842 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 843 | static struct ccid_operations ccid3 = { |
Ian McDonald | 3dd9a7c | 2006-09-22 14:26:44 +1200 | [diff] [blame] | 844 | .ccid_id = DCCPC_CCID3, |
Gerrit Renker | 84a97b0 | 2007-12-13 23:33:25 -0200 | [diff] [blame] | 845 | .ccid_name = "TCP-Friendly Rate Control", |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 846 | .ccid_owner = THIS_MODULE, |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 847 | .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] | 848 | .ccid_hc_tx_init = ccid3_hc_tx_init, |
| 849 | .ccid_hc_tx_exit = ccid3_hc_tx_exit, |
| 850 | .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, |
| 851 | .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, |
| 852 | .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 853 | .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 854 | .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] | 855 | .ccid_hc_rx_init = ccid3_hc_rx_init, |
| 856 | .ccid_hc_rx_exit = ccid3_hc_rx_exit, |
| 857 | .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, |
| 858 | .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv, |
Arnaldo Carvalho de Melo | 2babe1f | 2005-08-23 21:52:35 -0700 | [diff] [blame] | 859 | .ccid_hc_rx_get_info = ccid3_hc_rx_get_info, |
| 860 | .ccid_hc_tx_get_info = ccid3_hc_tx_get_info, |
Arnaldo Carvalho de Melo | 88f964d | 2005-09-18 00:19:32 -0700 | [diff] [blame] | 861 | .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt, |
| 862 | .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt, |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 863 | }; |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 864 | |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 865 | #ifdef CONFIG_IP_DCCP_CCID3_DEBUG |
Gerrit Renker | 4326499 | 2008-08-23 13:28:27 +0200 | [diff] [blame] | 866 | module_param(ccid3_debug, bool, 0644); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 867 | MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); |
Gerrit Renker | 56724aa | 2006-11-20 18:28:09 -0200 | [diff] [blame] | 868 | #endif |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 869 | |
| 870 | static __init int ccid3_module_init(void) |
| 871 | { |
Arnaldo Carvalho de Melo | 34a9e7e | 2007-12-06 12:28:13 -0200 | [diff] [blame] | 872 | return ccid_register(&ccid3); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 873 | } |
| 874 | module_init(ccid3_module_init); |
| 875 | |
| 876 | static __exit void ccid3_module_exit(void) |
| 877 | { |
| 878 | ccid_unregister(&ccid3); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 879 | } |
| 880 | module_exit(ccid3_module_exit); |
| 881 | |
Ian McDonald | e6bccd3 | 2006-08-26 19:01:30 -0700 | [diff] [blame] | 882 | MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, " |
Arnaldo Carvalho de Melo | 1f2333a | 2005-08-27 03:51:58 -0300 | [diff] [blame] | 883 | "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); |
Arnaldo Carvalho de Melo | 7c65787 | 2005-08-09 20:14:34 -0700 | [diff] [blame] | 884 | MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); |
| 885 | MODULE_LICENSE("GPL"); |
| 886 | MODULE_ALIAS("net-dccp-ccid-3"); |