1 /* 2 * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. 3 * Copyright (c) 2007 The University of Aberdeen, Scotland, UK 4 * 5 * An implementation of the DCCP protocol 6 * 7 * This code has been developed by the University of Waikato WAND 8 * research group. For further information please see http://www.wand.net.nz/ 9 * or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz 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 */ 35 #ifndef _DCCP_CCID3_H_ 36 #define _DCCP_CCID3_H_ 37 38 #include <linux/ktime.h> 39 #include <linux/list.h> 40 #include <linux/types.h> 41 #include <linux/tfrc.h> 42 #include "lib/tfrc.h" 43 #include "../ccid.h" 44 45 /* Two seconds as per RFC 5348, 4.2 */ 46 #define TFRC_INITIAL_TIMEOUT (2 * USEC_PER_SEC) 47 48 /* Parameter t_mbi from [RFC 3448, 4.3]: backoff interval in seconds */ 49 #define TFRC_T_MBI 64 50 51 /* 52 * The t_delta parameter (RFC 5348, 8.3): delays of less than %USEC_PER_MSEC are 53 * rounded down to 0, since sk_reset_timer() here uses millisecond granularity. 54 * Hence we can use a constant t_delta = %USEC_PER_MSEC when HZ >= 500. A coarse 55 * resolution of HZ < 500 means that the error is below one timer tick (t_gran) 56 * when using the constant t_delta = t_gran / 2 = %USEC_PER_SEC / (2 * HZ). 57 */ 58 #if (HZ >= 500) 59 # define TFRC_T_DELTA USEC_PER_MSEC 60 #else 61 # define TFRC_T_DELTA (USEC_PER_SEC / (2 * HZ)) 62 #endif 63 64 enum ccid3_options { 65 TFRC_OPT_LOSS_EVENT_RATE = 192, 66 TFRC_OPT_LOSS_INTERVALS = 193, 67 TFRC_OPT_RECEIVE_RATE = 194, 68 }; 69 70 /* TFRC sender states */ 71 enum ccid3_hc_tx_states { 72 TFRC_SSTATE_NO_SENT = 1, 73 TFRC_SSTATE_NO_FBACK, 74 TFRC_SSTATE_FBACK, 75 }; 76 77 /** 78 * struct ccid3_hc_tx_sock - CCID3 sender half-connection socket 79 * @tx_x: Current sending rate in 64 * bytes per second 80 * @tx_x_recv: Receive rate in 64 * bytes per second 81 * @tx_x_calc: Calculated rate in bytes per second 82 * @tx_rtt: Estimate of current round trip time in usecs 83 * @tx_p: Current loss event rate (0-1) scaled by 1000000 84 * @tx_s: Packet size in bytes 85 * @tx_t_rto: Nofeedback Timer setting in usecs 86 * @tx_t_ipi: Interpacket (send) interval (RFC 3448, 4.6) in usecs 87 * @tx_state: Sender state, one of %ccid3_hc_tx_states 88 * @tx_last_win_count: Last window counter sent 89 * @tx_t_last_win_count: Timestamp of earliest packet 90 * with last_win_count value sent 91 * @tx_no_feedback_timer: Handle to no feedback timer 92 * @tx_t_ld: Time last doubled during slow start 93 * @tx_t_nom: Nominal send time of next packet 94 * @tx_hist: Packet history 95 */ 96 struct ccid3_hc_tx_sock { 97 u64 tx_x; 98 u64 tx_x_recv; 99 u32 tx_x_calc; 100 u32 tx_rtt; 101 u32 tx_p; 102 u32 tx_t_rto; 103 u32 tx_t_ipi; 104 u16 tx_s; 105 enum ccid3_hc_tx_states tx_state:8; 106 u8 tx_last_win_count; 107 ktime_t tx_t_last_win_count; 108 struct timer_list tx_no_feedback_timer; 109 ktime_t tx_t_ld; 110 ktime_t tx_t_nom; 111 struct tfrc_tx_hist_entry *tx_hist; 112 }; 113 114 static inline struct ccid3_hc_tx_sock *ccid3_hc_tx_sk(const struct sock *sk) 115 { 116 struct ccid3_hc_tx_sock *hctx = ccid_priv(dccp_sk(sk)->dccps_hc_tx_ccid); 117 BUG_ON(hctx == NULL); 118 return hctx; 119 } 120 121 /* TFRC receiver states */ 122 enum ccid3_hc_rx_states { 123 TFRC_RSTATE_NO_DATA = 1, 124 TFRC_RSTATE_DATA, 125 }; 126 127 /** 128 * struct ccid3_hc_rx_sock - CCID3 receiver half-connection socket 129 * @rx_last_counter: Tracks window counter (RFC 4342, 8.1) 130 * @rx_state: Receiver state, one of %ccid3_hc_rx_states 131 * @rx_bytes_recv: Total sum of DCCP payload bytes 132 * @rx_x_recv: Receiver estimate of send rate (RFC 3448, sec. 4.3) 133 * @rx_rtt: Receiver estimate of RTT 134 * @rx_tstamp_last_feedback: Time at which last feedback was sent 135 * @rx_hist: Packet history (loss detection + RTT sampling) 136 * @rx_li_hist: Loss Interval database 137 * @rx_s: Received packet size in bytes 138 * @rx_pinv: Inverse of Loss Event Rate (RFC 4342, sec. 8.5) 139 */ 140 struct ccid3_hc_rx_sock { 141 u8 rx_last_counter:4; 142 enum ccid3_hc_rx_states rx_state:8; 143 u32 rx_bytes_recv; 144 u32 rx_x_recv; 145 u32 rx_rtt; 146 ktime_t rx_tstamp_last_feedback; 147 struct tfrc_rx_hist rx_hist; 148 struct tfrc_loss_hist rx_li_hist; 149 u16 rx_s; 150 #define rx_pinv rx_li_hist.i_mean 151 }; 152 153 static inline struct ccid3_hc_rx_sock *ccid3_hc_rx_sk(const struct sock *sk) 154 { 155 struct ccid3_hc_rx_sock *hcrx = ccid_priv(dccp_sk(sk)->dccps_hc_rx_ccid); 156 BUG_ON(hcrx == NULL); 157 return hcrx; 158 } 159 160 #endif /* _DCCP_CCID3_H_ */ 161