1 /*- 2 * Copyright (c) 2007-2008 3 * Swinburne University of Technology, Melbourne, Australia. 4 * Copyright (c) 2009-2010 Lawrence Stewart <lstewart@freebsd.org> 5 * Copyright (c) 2010 The FreeBSD Foundation 6 * All rights reserved. 7 * 8 * This software was developed at the Centre for Advanced Internet 9 * Architectures, Swinburne University of Technology, by Lawrence Stewart and 10 * James Healy, made possible in part by a grant from the Cisco University 11 * Research Program Fund at Community Foundation Silicon Valley. 12 * 13 * Portions of this software were developed at the Centre for Advanced 14 * Internet Architectures, Swinburne University of Technology, Melbourne, 15 * Australia by David Hayes under sponsorship from the FreeBSD Foundation. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions 19 * are met: 20 * 1. Redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer. 22 * 2. Redistributions in binary form must reproduce the above copyright 23 * notice, this list of conditions and the following disclaimer in the 24 * documentation and/or other materials provided with the distribution. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * $FreeBSD$ 39 */ 40 41 /* 42 * This software was first released in 2007 by James Healy and Lawrence Stewart 43 * whilst working on the NewTCP research project at Swinburne University of 44 * Technology's Centre for Advanced Internet Architectures, Melbourne, 45 * Australia, which was made possible in part by a grant from the Cisco 46 * University Research Program Fund at Community Foundation Silicon Valley. 47 * More details are available at: 48 * http://caia.swin.edu.au/urp/newtcp/ 49 */ 50 51 #ifndef _NETINET_CC_H_ 52 #define _NETINET_CC_H_ 53 54 /* XXX: TCP_CA_NAME_MAX define lives in tcp.h for compat reasons. */ 55 #include <netinet/tcp.h> 56 57 /* Global CC vars. */ 58 extern STAILQ_HEAD(cc_head, cc_algo) cc_list; 59 extern const int tcprexmtthresh; 60 extern struct cc_algo newreno_cc_algo; 61 62 /* Per-netstack bits. */ 63 VNET_DECLARE(struct cc_algo *, default_cc_ptr); 64 #define V_default_cc_ptr VNET(default_cc_ptr) 65 66 /* Define the new net.inet.tcp.cc sysctl tree. */ 67 SYSCTL_DECL(_net_inet_tcp_cc); 68 69 /* CC housekeeping functions. */ 70 int cc_register_algo(struct cc_algo *add_cc); 71 int cc_deregister_algo(struct cc_algo *remove_cc); 72 73 /* 74 * Wrapper around transport structs that contain same-named congestion 75 * control variables. Allows algos to be shared amongst multiple CC aware 76 * transprots. 77 */ 78 struct cc_var { 79 void *cc_data; /* Per-connection private CC algorithm data. */ 80 int bytes_this_ack; /* # bytes acked by the current ACK. */ 81 tcp_seq curack; /* Most recent ACK. */ 82 uint32_t flags; /* Flags for cc_var (see below) */ 83 int type; /* Indicates which ptr is valid in ccvc. */ 84 union ccv_container { 85 struct tcpcb *tcp; 86 struct sctp_nets *sctp; 87 } ccvc; 88 }; 89 90 /* cc_var flags. */ 91 #define CCF_ABC_SENTAWND 0x0001 /* ABC counted cwnd worth of bytes? */ 92 #define CCF_CWND_LIMITED 0x0002 /* Are we currently cwnd limited? */ 93 #define CCF_DELACK 0x0004 /* Is this ack delayed? */ 94 #define CCF_ACKNOW 0x0008 /* Will this ack be sent now? */ 95 #define CCF_IPHDR_CE 0x0010 /* Does this packet set CE bit? */ 96 #define CCF_TCPHDR_CWR 0x0020 /* Does this packet set CWR bit? */ 97 98 /* ACK types passed to the ack_received() hook. */ 99 #define CC_ACK 0x0001 /* Regular in sequence ACK. */ 100 #define CC_DUPACK 0x0002 /* Duplicate ACK. */ 101 #define CC_PARTIALACK 0x0004 /* Not yet. */ 102 #define CC_SACK 0x0008 /* Not yet. */ 103 104 /* 105 * Congestion signal types passed to the cong_signal() hook. The highest order 8 106 * bits (0x01000000 - 0x80000000) are reserved for CC algos to declare their own 107 * congestion signal types. 108 */ 109 #define CC_ECN 0x00000001 /* ECN marked packet received. */ 110 #define CC_RTO 0x00000002 /* RTO fired. */ 111 #define CC_RTO_ERR 0x00000004 /* RTO fired in error. */ 112 #define CC_NDUPACK 0x00000008 /* Threshold of dupack's reached. */ 113 114 #define CC_SIGPRIVMASK 0xFF000000 /* Mask to check if sig is private. */ 115 116 /* 117 * Structure to hold data and function pointers that together represent a 118 * congestion control algorithm. 119 */ 120 struct cc_algo { 121 char name[TCP_CA_NAME_MAX]; 122 123 /* Init global module state on kldload. */ 124 int (*mod_init)(void); 125 126 /* Cleanup global module state on kldunload. */ 127 int (*mod_destroy)(void); 128 129 /* Init CC state for a new control block. */ 130 int (*cb_init)(struct cc_var *ccv); 131 132 /* Cleanup CC state for a terminating control block. */ 133 void (*cb_destroy)(struct cc_var *ccv); 134 135 /* Init variables for a newly established connection. */ 136 void (*conn_init)(struct cc_var *ccv); 137 138 /* Called on receipt of an ack. */ 139 void (*ack_received)(struct cc_var *ccv, uint16_t type); 140 141 /* Called on detection of a congestion signal. */ 142 void (*cong_signal)(struct cc_var *ccv, uint32_t type); 143 144 /* Called after exiting congestion recovery. */ 145 void (*post_recovery)(struct cc_var *ccv); 146 147 /* Called when data transfer resumes after an idle period. */ 148 void (*after_idle)(struct cc_var *ccv); 149 150 /* Called for an additional ECN processing apart from RFC3168. */ 151 void (*ecnpkt_handler)(struct cc_var *ccv); 152 153 STAILQ_ENTRY (cc_algo) entries; 154 }; 155 156 /* Macro to obtain the CC algo's struct ptr. */ 157 #define CC_ALGO(tp) ((tp)->cc_algo) 158 159 /* Macro to obtain the CC algo's data ptr. */ 160 #define CC_DATA(tp) ((tp)->ccv->cc_data) 161 162 /* Macro to obtain the system default CC algo's struct ptr. */ 163 #define CC_DEFAULT() V_default_cc_ptr 164 165 extern struct rwlock cc_list_lock; 166 #define CC_LIST_LOCK_INIT() rw_init(&cc_list_lock, "cc_list") 167 #define CC_LIST_LOCK_DESTROY() rw_destroy(&cc_list_lock) 168 #define CC_LIST_RLOCK() rw_rlock(&cc_list_lock) 169 #define CC_LIST_RUNLOCK() rw_runlock(&cc_list_lock) 170 #define CC_LIST_WLOCK() rw_wlock(&cc_list_lock) 171 #define CC_LIST_WUNLOCK() rw_wunlock(&cc_list_lock) 172 #define CC_LIST_LOCK_ASSERT() rw_assert(&cc_list_lock, RA_LOCKED) 173 174 #endif /* _NETINET_CC_H_ */ 175