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 #ifdef _KERNEL 55 56 MALLOC_DECLARE(M_CC_MEM); 57 58 /* Global CC vars. */ 59 extern STAILQ_HEAD(cc_head, cc_algo) cc_list; 60 extern const int tcprexmtthresh; 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 VNET_DECLARE(int, cc_do_abe); 67 #define V_cc_do_abe VNET(cc_do_abe) 68 69 VNET_DECLARE(int, cc_abe_frlossreduce); 70 #define V_cc_abe_frlossreduce VNET(cc_abe_frlossreduce) 71 72 /* Define the new net.inet.tcp.cc sysctl tree. */ 73 SYSCTL_DECL(_net_inet_tcp_cc); 74 75 /* CC housekeeping functions. */ 76 int cc_register_algo(struct cc_algo *add_cc); 77 int cc_deregister_algo(struct cc_algo *remove_cc); 78 79 /* 80 * Wrapper around transport structs that contain same-named congestion 81 * control variables. Allows algos to be shared amongst multiple CC aware 82 * transprots. 83 */ 84 struct cc_var { 85 void *cc_data; /* Per-connection private CC algorithm data. */ 86 int bytes_this_ack; /* # bytes acked by the current ACK. */ 87 tcp_seq curack; /* Most recent ACK. */ 88 uint32_t flags; /* Flags for cc_var (see below) */ 89 int type; /* Indicates which ptr is valid in ccvc. */ 90 union ccv_container { 91 struct tcpcb *tcp; 92 struct sctp_nets *sctp; 93 } ccvc; 94 uint16_t nsegs; /* # segments coalesced into current chain. */ 95 uint8_t labc; /* Dont use system abc use passed in */ 96 }; 97 98 /* cc_var flags. */ 99 #define CCF_ABC_SENTAWND 0x0001 /* ABC counted cwnd worth of bytes? */ 100 #define CCF_CWND_LIMITED 0x0002 /* Are we currently cwnd limited? */ 101 #define CCF_USE_LOCAL_ABC 0x0004 /* Dont use the system l_abc val */ 102 #define CCF_ACKNOW 0x0008 /* Will this ack be sent now? */ 103 #define CCF_IPHDR_CE 0x0010 /* Does this packet set CE bit? */ 104 #define CCF_TCPHDR_CWR 0x0020 /* Does this packet set CWR bit? */ 105 #define CCF_MAX_CWND 0x0040 /* Have we reached maximum cwnd? */ 106 #define CCF_CHG_MAX_CWND 0x0080 /* Cubic max_cwnd changed, for K */ 107 #define CCF_USR_IWND 0x0100 /* User specified initial window */ 108 #define CCF_USR_IWND_INIT_NSEG 0x0200 /* Convert segs to bytes on conn init */ 109 110 /* ACK types passed to the ack_received() hook. */ 111 #define CC_ACK 0x0001 /* Regular in sequence ACK. */ 112 #define CC_DUPACK 0x0002 /* Duplicate ACK. */ 113 #define CC_PARTIALACK 0x0004 /* Not yet. */ 114 #define CC_SACK 0x0008 /* Not yet. */ 115 #endif /* _KERNEL */ 116 117 /* 118 * Congestion signal types passed to the cong_signal() hook. The highest order 8 119 * bits (0x01000000 - 0x80000000) are reserved for CC algos to declare their own 120 * congestion signal types. 121 */ 122 #define CC_ECN 0x00000001 /* ECN marked packet received. */ 123 #define CC_RTO 0x00000002 /* RTO fired. */ 124 #define CC_RTO_ERR 0x00000004 /* RTO fired in error. */ 125 #define CC_NDUPACK 0x00000008 /* Threshold of dupack's reached. */ 126 127 #define CC_SIGPRIVMASK 0xFF000000 /* Mask to check if sig is private. */ 128 129 #ifdef _KERNEL 130 /* 131 * Structure to hold data and function pointers that together represent a 132 * congestion control algorithm. 133 */ 134 struct cc_algo { 135 char name[TCP_CA_NAME_MAX]; 136 137 /* Init global module state on kldload. */ 138 int (*mod_init)(void); 139 140 /* Cleanup global module state on kldunload. */ 141 int (*mod_destroy)(void); 142 143 /* Return the size of the void pointer the CC needs for state */ 144 size_t (*cc_data_sz)(void); 145 146 /* 147 * Init CC state for a new control block. The CC 148 * module may be passed a NULL ptr indicating that 149 * it must allocate the memory. If it is passed a 150 * non-null pointer it is pre-allocated memory by 151 * the caller and the cb_init is expected to use that memory. 152 * It is not expected to fail if memory is passed in and 153 * all currently defined modules do not. 154 */ 155 int (*cb_init)(struct cc_var *ccv, void *ptr); 156 157 /* Cleanup CC state for a terminating control block. */ 158 void (*cb_destroy)(struct cc_var *ccv); 159 160 /* Init variables for a newly established connection. */ 161 void (*conn_init)(struct cc_var *ccv); 162 163 /* Called on receipt of an ack. */ 164 void (*ack_received)(struct cc_var *ccv, uint16_t type); 165 166 /* Called on detection of a congestion signal. */ 167 void (*cong_signal)(struct cc_var *ccv, uint32_t type); 168 169 /* Called after exiting congestion recovery. */ 170 void (*post_recovery)(struct cc_var *ccv); 171 172 /* Called when data transfer resumes after an idle period. */ 173 void (*after_idle)(struct cc_var *ccv); 174 175 /* Called for an additional ECN processing apart from RFC3168. */ 176 void (*ecnpkt_handler)(struct cc_var *ccv); 177 178 /* Called when a new "round" begins, if the transport is tracking rounds. */ 179 void (*newround)(struct cc_var *ccv, uint32_t round_cnt); 180 181 /* 182 * Called when a RTT sample is made (fas = flight at send, if you dont have it 183 * send the cwnd in). 184 */ 185 void (*rttsample)(struct cc_var *ccv, uint32_t usec_rtt, uint32_t rxtcnt, uint32_t fas); 186 187 /* Called for {get|set}sockopt() on a TCP socket with TCP_CCALGOOPT. */ 188 int (*ctl_output)(struct cc_var *, struct sockopt *, void *); 189 190 STAILQ_ENTRY (cc_algo) entries; 191 uint8_t flags; 192 }; 193 194 #define CC_MODULE_BEING_REMOVED 0x01 /* The module is being removed */ 195 196 /* Macro to obtain the CC algo's struct ptr. */ 197 #define CC_ALGO(tp) ((tp)->cc_algo) 198 199 /* Macro to obtain the CC algo's data ptr. */ 200 #define CC_DATA(tp) ((tp)->ccv->cc_data) 201 202 /* Macro to obtain the system default CC algo's struct ptr. */ 203 #define CC_DEFAULT_ALGO() V_default_cc_ptr 204 205 extern struct rwlock cc_list_lock; 206 #define CC_LIST_LOCK_INIT() rw_init(&cc_list_lock, "cc_list") 207 #define CC_LIST_LOCK_DESTROY() rw_destroy(&cc_list_lock) 208 #define CC_LIST_RLOCK() rw_rlock(&cc_list_lock) 209 #define CC_LIST_RUNLOCK() rw_runlock(&cc_list_lock) 210 #define CC_LIST_WLOCK() rw_wlock(&cc_list_lock) 211 #define CC_LIST_WUNLOCK() rw_wunlock(&cc_list_lock) 212 #define CC_LIST_LOCK_ASSERT() rw_assert(&cc_list_lock, RA_LOCKED) 213 214 #define CC_ALGOOPT_LIMIT 2048 215 216 /* 217 * These routines give NewReno behavior to the caller 218 * they require no state and can be used by any other CC 219 * module that wishes to use NewReno type behaviour (along 220 * with anything else they may add on, pre or post call). 221 */ 222 void newreno_cc_post_recovery(struct cc_var *); 223 void newreno_cc_after_idle(struct cc_var *); 224 void newreno_cc_cong_signal(struct cc_var *, uint32_t ); 225 void newreno_cc_ack_received(struct cc_var *, uint16_t); 226 227 #endif /* _KERNEL */ 228 #endif /* _NETINET_CC_CC_H_ */ 229