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
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.
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.
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
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.
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
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/
51 #ifndef _NETINET_CC_CC_H_
52 #define _NETINET_CC_CC_H_
55 #error "no user-servicable parts inside"
59 extern STAILQ_HEAD(cc_head, cc_algo) cc_list;
60 extern const int tcprexmtthresh;
61 extern struct cc_algo newreno_cc_algo;
63 /* Per-netstack bits. */
64 VNET_DECLARE(struct cc_algo *, default_cc_ptr);
65 #define V_default_cc_ptr VNET(default_cc_ptr)
67 /* Define the new net.inet.tcp.cc sysctl tree. */
68 SYSCTL_DECL(_net_inet_tcp_cc);
70 /* CC housekeeping functions. */
71 int cc_register_algo(struct cc_algo *add_cc);
72 int cc_deregister_algo(struct cc_algo *remove_cc);
75 * Wrapper around transport structs that contain same-named congestion
76 * control variables. Allows algos to be shared amongst multiple CC aware
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. */
87 struct sctp_nets *sctp;
89 uint16_t nsegs; /* # segments coalesced into current chain. */
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? */
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. */
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.
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. */
116 #define CC_SIGPRIVMASK 0xFF000000 /* Mask to check if sig is private. */
119 * Structure to hold data and function pointers that together represent a
120 * congestion control algorithm.
123 char name[TCP_CA_NAME_MAX];
125 /* Init global module state on kldload. */
126 int (*mod_init)(void);
128 /* Cleanup global module state on kldunload. */
129 int (*mod_destroy)(void);
131 /* Init CC state for a new control block. */
132 int (*cb_init)(struct cc_var *ccv);
134 /* Cleanup CC state for a terminating control block. */
135 void (*cb_destroy)(struct cc_var *ccv);
137 /* Init variables for a newly established connection. */
138 void (*conn_init)(struct cc_var *ccv);
140 /* Called on receipt of an ack. */
141 void (*ack_received)(struct cc_var *ccv, uint16_t type);
143 /* Called on detection of a congestion signal. */
144 void (*cong_signal)(struct cc_var *ccv, uint32_t type);
146 /* Called after exiting congestion recovery. */
147 void (*post_recovery)(struct cc_var *ccv);
149 /* Called when data transfer resumes after an idle period. */
150 void (*after_idle)(struct cc_var *ccv);
152 /* Called for an additional ECN processing apart from RFC3168. */
153 void (*ecnpkt_handler)(struct cc_var *ccv);
155 /* Called for {get|set}sockopt() on a TCP socket with TCP_CCALGOOPT. */
156 int (*ctl_output)(struct cc_var *, struct sockopt *, void *);
158 STAILQ_ENTRY (cc_algo) entries;
161 /* Macro to obtain the CC algo's struct ptr. */
162 #define CC_ALGO(tp) ((tp)->cc_algo)
164 /* Macro to obtain the CC algo's data ptr. */
165 #define CC_DATA(tp) ((tp)->ccv->cc_data)
167 /* Macro to obtain the system default CC algo's struct ptr. */
168 #define CC_DEFAULT() V_default_cc_ptr
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)
179 #endif /* _NETINET_CC_CC_H_ */