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_CC_H_ 52 #define _NETINET_CC_CC_H_ 53 54 #if !defined(_KERNEL) 55 #error "no user-serviceable parts inside" 56 #endif 57 58 /* Global CC vars. */ 59 extern STAILQ_HEAD(cc_head, cc_algo) cc_list; 60 extern const int tcprexmtthresh; 61 extern struct cc_algo newreno_cc_algo; 62 63 /* Per-netstack bits. */ 64 VNET_DECLARE(struct cc_algo *, default_cc_ptr); 65 #define V_default_cc_ptr VNET(default_cc_ptr) 66 67 /* Define the new net.inet.tcp.cc sysctl tree. */ 68 SYSCTL_DECL(_net_inet_tcp_cc); 69 70 /* CC housekeeping functions. */ 71 int cc_register_algo(struct cc_algo *add_cc); 72 int cc_deregister_algo(struct cc_algo *remove_cc); 73 74 /* 75 * Wrapper around transport structs that contain same-named congestion 76 * control variables. Allows algos to be shared amongst multiple CC aware 77 * transprots. 78 */ 79 struct cc_var { 80 void *cc_data; /* Per-connection private CC algorithm data. */ 81 int bytes_this_ack; /* # bytes acked by the current ACK. */ 82 tcp_seq curack; /* Most recent ACK. */ 83 uint32_t flags; /* Flags for cc_var (see below) */ 84 int type; /* Indicates which ptr is valid in ccvc. */ 85 union ccv_container { 86 struct tcpcb *tcp; 87 struct sctp_nets *sctp; 88 } ccvc; 89 uint16_t nsegs; /* # segments coalesced into current chain. */ 90 }; 91 92 /* cc_var flags. */ 93 #define CCF_ABC_SENTAWND 0x0001 /* ABC counted cwnd worth of bytes? */ 94 #define CCF_CWND_LIMITED 0x0002 /* Are we currently cwnd limited? */ 95 #define CCF_DELACK 0x0004 /* Is this ack delayed? */ 96 #define CCF_ACKNOW 0x0008 /* Will this ack be sent now? */ 97 #define CCF_IPHDR_CE 0x0010 /* Does this packet set CE bit? */ 98 #define CCF_TCPHDR_CWR 0x0020 /* Does this packet set CWR bit? */ 99 100 /* ACK types passed to the ack_received() hook. */ 101 #define CC_ACK 0x0001 /* Regular in sequence ACK. */ 102 #define CC_DUPACK 0x0002 /* Duplicate ACK. */ 103 #define CC_PARTIALACK 0x0004 /* Not yet. */ 104 #define CC_SACK 0x0008 /* Not yet. */ 105 106 /* 107 * Congestion signal types passed to the cong_signal() hook. The highest order 8 108 * bits (0x01000000 - 0x80000000) are reserved for CC algos to declare their own 109 * congestion signal types. 110 */ 111 #define CC_ECN 0x00000001 /* ECN marked packet received. */ 112 #define CC_RTO 0x00000002 /* RTO fired. */ 113 #define CC_RTO_ERR 0x00000004 /* RTO fired in error. */ 114 #define CC_NDUPACK 0x00000008 /* Threshold of dupack's reached. */ 115 116 #define CC_SIGPRIVMASK 0xFF000000 /* Mask to check if sig is private. */ 117 118 /* 119 * Structure to hold data and function pointers that together represent a 120 * congestion control algorithm. 121 */ 122 struct cc_algo { 123 char name[TCP_CA_NAME_MAX]; 124 125 /* Init global module state on kldload. */ 126 int (*mod_init)(void); 127 128 /* Cleanup global module state on kldunload. */ 129 int (*mod_destroy)(void); 130 131 /* Init CC state for a new control block. */ 132 int (*cb_init)(struct cc_var *ccv); 133 134 /* Cleanup CC state for a terminating control block. */ 135 void (*cb_destroy)(struct cc_var *ccv); 136 137 /* Init variables for a newly established connection. */ 138 void (*conn_init)(struct cc_var *ccv); 139 140 /* Called on receipt of an ack. */ 141 void (*ack_received)(struct cc_var *ccv, uint16_t type); 142 143 /* Called on detection of a congestion signal. */ 144 void (*cong_signal)(struct cc_var *ccv, uint32_t type); 145 146 /* Called after exiting congestion recovery. */ 147 void (*post_recovery)(struct cc_var *ccv); 148 149 /* Called when data transfer resumes after an idle period. */ 150 void (*after_idle)(struct cc_var *ccv); 151 152 /* Called for an additional ECN processing apart from RFC3168. */ 153 void (*ecnpkt_handler)(struct cc_var *ccv); 154 155 /* Called for {get|set}sockopt() on a TCP socket with TCP_CCALGOOPT. */ 156 int (*ctl_output)(struct cc_var *, struct sockopt *, void *); 157 158 STAILQ_ENTRY (cc_algo) entries; 159 }; 160 161 /* Macro to obtain the CC algo's struct ptr. */ 162 #define CC_ALGO(tp) ((tp)->cc_algo) 163 164 /* Macro to obtain the CC algo's data ptr. */ 165 #define CC_DATA(tp) ((tp)->ccv->cc_data) 166 167 /* Macro to obtain the system default CC algo's struct ptr. */ 168 #define CC_DEFAULT() V_default_cc_ptr 169 170 extern struct rwlock cc_list_lock; 171 #define CC_LIST_LOCK_INIT() rw_init(&cc_list_lock, "cc_list") 172 #define CC_LIST_LOCK_DESTROY() rw_destroy(&cc_list_lock) 173 #define CC_LIST_RLOCK() rw_rlock(&cc_list_lock) 174 #define CC_LIST_RUNLOCK() rw_runlock(&cc_list_lock) 175 #define CC_LIST_WLOCK() rw_wlock(&cc_list_lock) 176 #define CC_LIST_WUNLOCK() rw_wunlock(&cc_list_lock) 177 #define CC_LIST_LOCK_ASSERT() rw_assert(&cc_list_lock, RA_LOCKED) 178 179 #endif /* _NETINET_CC_CC_H_ */ 180