bsd/netinet/tcp_cc.h

   1 /*
   2  * Copyright (c) 2010-2011 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*-
  29  * Copyright (c) 2008 Swinburne University of Technology, Melbourne, Australia
  30  * All rights reserved.
  31  *
  32  * This software was developed at the Centre for Advanced Internet
  33  * Architectures, Swinburne University, by Lawrence Stewart and James Healy,
  34  * made possible in part by a grant from the Cisco University Research Program
  35  * Fund at Community Foundation Silicon Valley.
  36  *
  37  * Redistribution and use in source and binary forms, with or without
  38  * modification, are permitted provided that the following conditions
  39  * are met:
  40  * 1. Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  * 2. Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in the
  44  *    documentation and/or other materials provided with the distribution.
  45  *
  46  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  49  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  56  * SUCH DAMAGE.
  57  *
  58  * $FreeBSD$
  59  */
  60
  61 #ifndef _NETINET_CC_H_
  62 #define _NETINET_CC_H_
  63
  64 #ifdef KERNEL
  65
  66 #include <netinet/tcp_var.h>
  67
  68 #define TCP_CC_ALGO_NEWRENO_INDEX 0     /* default congestion control algorithm */
  69 #define TCP_CC_ALGO_BACKGROUND_INDEX 1  /* congestion control for background transport */
  70 #define TCP_CC_ALGO_COUNT 2             /* Count of CC algorithms defined */
  71
  72 #define TCP_CA_NAME_MAX 16              /* Maximum characters in the name of a CC algorithm */
  73
  74 /*
  75  * Structure to hold definition various actions defined by a congestion control
  76  * algorithm for TCP. This can be used to change the congestion control on a
  77  * connection based on the user settings of priority of a connection.
  78  */
  79 struct tcp_cc_algo {
  80         char name[TCP_CA_NAME_MAX];
  81         uint32_t num_sockets;
  82         uint32_t flags;
  83
  84         /* init the congestion algorithm for the specified control block */
  85         int (*init) (struct tcpcb *tp);
  86
  87         /* cleanup any state that is stored in the connection related to the algorithm */
  88         int (*cleanup) (struct tcpcb *tp);
  89
  90         /* initialize cwnd at the start of a connection */
  91         void (*cwnd_init) (struct tcpcb *tp);
  92
  93         /* called on the receipt of in-sequence ack during congestion avoidance phase */
  94         void (*inseq_ack_rcvd) (struct tcpcb *tp, struct tcphdr *th);
  95
  96         /* called on the receipt of a valid ack */
  97         void (*ack_rcvd) (struct tcpcb *tp, struct tcphdr *th);
  98
  99         /* called before entering FR */
 100         void (*pre_fr) (struct tcpcb *tp);
 101
 102         /*  after exiting FR */
 103         void (*post_fr) (struct tcpcb *tp, struct tcphdr *th);
 104
 105         /* perform tasks when data transfer resumes after an idle period */
 106         void (*after_idle) (struct tcpcb *tp);
 107
 108         /* perform tasks when the connection's retransmit timer expires */
 109         void (*after_timeout) (struct tcpcb *tp);
 110
 111         /* Whether or not to delay the ack */
 112         int (*delay_ack)(struct tcpcb *tp, struct tcphdr *th);
 113
 114         /* Switch a connection to this CC algorithm after sending some packets */
 115         void (*switch_to)(struct tcpcb *tp, uint16_t old_cc_index);
 116
 117 } __attribute__((aligned(4)));
 118
 119 extern struct tcp_cc_algo* tcp_cc_algo_list[TCP_CC_ALGO_COUNT];
 120
 121 #define CC_ALGO(tp) (tcp_cc_algo_list[tp->tcp_cc_index])
 122
 123 extern void tcp_cc_resize_sndbuf(struct tcpcb *tp);
 124 extern void tcp_bad_rexmt_fix_sndbuf(struct tcpcb *tp);
 125
 126 #endif /* KERNEL */
 127 #endif /* _NETINET_CC_H_ */