/*-
* Copyright (c) 2007-2008
* Swinburne University of Technology, Melbourne, Australia.
* Copyright (c) 2009-2010 Lawrence Stewart <lstewart@freebsd.org>
* Copyright (c) 2010 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed at the Centre for Advanced Internet
* Architectures, Swinburne University of Technology, by Lawrence Stewart and
* James Healy, made possible in part by a grant from the Cisco University
* Research Program Fund at Community Foundation Silicon Valley.
*
* Portions of this software were developed at the Centre for Advanced
* Internet Architectures, Swinburne University of Technology, Melbourne,
* Australia by David Hayes under sponsorship from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* This software was first released in 2007 by James Healy and Lawrence Stewart
* whilst working on the NewTCP research project at Swinburne University of
* Technology's Centre for Advanced Internet Architectures, Melbourne,
* Australia, which was made possible in part by a grant from the Cisco
* University Research Program Fund at Community Foundation Silicon Valley.
* More details are available at:
* http://caia.swin.edu.au/urp/newtcp/
*/
#ifndef _NETINET_CC_H_
#define _NETINET_CC_H_
/* XXX: TCP_CA_NAME_MAX define lives in tcp.h for compat reasons. */
#include <netinet/tcp.h>
/* Global CC vars. */
extern STAILQ_HEAD(cc_head, cc_algo) cc_list;
extern const int tcprexmtthresh;
extern struct cc_algo newreno_cc_algo;
/* Per-netstack bits. */
VNET_DECLARE(struct cc_algo *, default_cc_ptr);
#define V_default_cc_ptr VNET(default_cc_ptr)
/* Define the new net.inet.tcp.cc sysctl tree. */
SYSCTL_DECL(_net_inet_tcp_cc);
/* CC housekeeping functions. */
int cc_register_algo(struct cc_algo *add_cc);
int cc_deregister_algo(struct cc_algo *remove_cc);
/*
* Wrapper around transport structs that contain same-named congestion
* control variables. Allows algos to be shared amongst multiple CC aware
* transprots.
*/
struct cc_var {
void *cc_data; /* Per-connection private CC algorithm data. */
int bytes_this_ack; /* # bytes acked by the current ACK. */
tcp_seq curack; /* Most recent ACK. */
uint32_t flags; /* Flags for cc_var (see below) */
int type; /* Indicates which ptr is valid in ccvc. */
union ccv_container {
struct tcpcb *tcp;
struct sctp_nets *sctp;
} ccvc;
};
/* cc_var flags. */
#define CCF_ABC_SENTAWND 0x0001 /* ABC counted cwnd worth of bytes? */
#define CCF_CWND_LIMITED 0x0002 /* Are we currently cwnd limited? */
/* ACK types passed to the ack_received() hook. */
#define CC_ACK 0x0001 /* Regular in sequence ACK. */
#define CC_DUPACK 0x0002 /* Duplicate ACK. */
#define CC_PARTIALACK 0x0004 /* Not yet. */
#define CC_SACK 0x0008 /* Not yet. */
/*
* Congestion signal types passed to the cong_signal() hook. The highest order 8
* bits (0x01000000 - 0x80000000) are reserved for CC algos to declare their own
* congestion signal types.
*/
#define CC_ECN 0x00000001 /* ECN marked packet received. */
#define CC_RTO 0x00000002 /* RTO fired. */
#define CC_RTO_ERR 0x00000004 /* RTO fired in error. */
#define CC_NDUPACK 0x00000008 /* Threshold of dupack's reached. */
#define CC_SIGPRIVMASK 0xFF000000 /* Mask to check if sig is private. */
/*
* Structure to hold data and function pointers that together represent a
* congestion control algorithm.
*/
struct cc_algo {
char name[TCP_CA_NAME_MAX];
/* Init global module state on kldload. */
int (*mod_init)(void);
/* Cleanup global module state on kldunload. */
int (*mod_destroy)(void);
/* Init CC state for a new control block. */
int (*cb_init)(struct cc_var *ccv);
/* Cleanup CC state for a terminating control block. */
void (*cb_destroy)(struct cc_var *ccv);
/* Init variables for a newly established connection. */
void (*conn_init)(struct cc_var *ccv);
/* Called on receipt of an ack. */
void (*ack_received)(struct cc_var *ccv, uint16_t type);
/* Called on detection of a congestion signal. */
void (*cong_signal)(struct cc_var *ccv, uint32_t type);
/* Called after exiting congestion recovery. */
void (*post_recovery)(struct cc_var *ccv);
/* Called when data transfer resumes after an idle period. */
void (*after_idle)(struct cc_var *ccv);
STAILQ_ENTRY (cc_algo) entries;
};
/* Macro to obtain the CC algo's struct ptr. */
#define CC_ALGO(tp) ((tp)->cc_algo)
/* Macro to obtain the CC algo's data ptr. */
#define CC_DATA(tp) ((tp)->ccv->cc_data)
/* Macro to obtain the system default CC algo's struct ptr. */
#define CC_DEFAULT() V_default_cc_ptr
extern struct rwlock cc_list_lock;
#define CC_LIST_LOCK_INIT() rw_init(&cc_list_lock, "cc_list")
#define CC_LIST_LOCK_DESTROY() rw_destroy(&cc_list_lock)
#define CC_LIST_RLOCK() rw_rlock(&cc_list_lock)
#define CC_LIST_RUNLOCK() rw_runlock(&cc_list_lock)
#define CC_LIST_WLOCK() rw_wlock(&cc_list_lock)
#define CC_LIST_WUNLOCK() rw_wunlock(&cc_list_lock)
#define CC_LIST_LOCK_ASSERT() rw_assert(&cc_list_lock, RA_LOCKED)
#endif /* _NETINET_CC_H_ */
