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/*-
* 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.
*/
/*
* 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_CC_H_
#define _NETINET_CC_CC_H_
#ifdef _KERNEL
MALLOC_DECLARE(M_CC_MEM);
/* Global CC vars. */
extern STAILQ_HEAD(cc_head, cc_algo) cc_list;
extern const int tcprexmtthresh;
/* Per-netstack bits. */
VNET_DECLARE(struct cc_algo *, default_cc_ptr);
#define V_default_cc_ptr VNET(default_cc_ptr)
VNET_DECLARE(int, cc_do_abe);
#define V_cc_do_abe VNET(cc_do_abe)
VNET_DECLARE(int, cc_abe_frlossreduce);
#define V_cc_abe_frlossreduce VNET(cc_abe_frlossreduce)
/* Define the new net.inet.tcp.cc sysctl tree. */
#ifdef _SYS_SYSCTL_H_
SYSCTL_DECL(_net_inet_tcp_cc);
#endif
/* For CC modules that use hystart++ */
extern uint32_t hystart_lowcwnd;
extern uint32_t hystart_minrtt_thresh;
extern uint32_t hystart_maxrtt_thresh;
extern uint32_t hystart_n_rttsamples;
extern uint32_t hystart_css_growth_div;
extern uint32_t hystart_css_rounds;
extern uint32_t hystart_bblogs;
/* CC housekeeping functions. */
int cc_register_algo(struct cc_algo *add_cc);
int cc_deregister_algo(struct cc_algo *remove_cc);
#endif /* _KERNEL */
#if defined(_KERNEL) || defined(_WANT_TCPCB)
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) */
struct tcpcb *tp; /* Pointer to tcpcb */
uint16_t nsegs; /* # segments coalesced into current chain. */
uint8_t labc; /* Dont use system abc use passed in */
};
/* cc_var flags. */
#define CCF_ABC_SENTAWND 0x0001 /* ABC counted cwnd worth of bytes? */
#define CCF_CWND_LIMITED 0x0002 /* Are we currently cwnd limited? */
#define CCF_USE_LOCAL_ABC 0x0004 /* Dont use the system l_abc val */
#define CCF_ACKNOW 0x0008 /* Will this ack be sent now? */
#define CCF_IPHDR_CE 0x0010 /* Does this packet set CE bit? */
#define CCF_TCPHDR_CWR 0x0020 /* Does this packet set CWR bit? */
#define CCF_UNUSED1 0x0040
#define CCF_UNUSED2 0x0080
#define CCF_UNUSED3 0x0100
#define CCF_UNUSED4 0x0200
#define CCF_HYSTART_ALLOWED 0x0400 /* If the CC supports it Hystart is allowed */
#define CCF_HYSTART_CAN_SH_CWND 0x0800 /* Can hystart when going CSS -> CA slam the cwnd */
#define CCF_HYSTART_CONS_SSTH 0x1000 /* Should hystart use the more conservative ssthresh */
#endif /* defined(_KERNEL) || defined(_WANT_TCPCB) */
typedef enum {
#if defined(_KERNEL) || defined(_WANT_TCPCB)
/* ACK types passed to the ack_received() hook. */
CC_ACK = 0x0001, /* Regular in sequence ACK. */
CC_DUPACK = 0x0002, /* Duplicate ACK. */
CC_PARTIALACK = 0x0004, /* Not yet. */
CC_SACK = 0x0008, /* Not yet. */
#endif /* defined(_KERNEL) || defined(_WANT_TCPCB) */
/* Congestion signal types passed to the cong_signal() hook. */
CC_ECN = 0x0100, /* ECN marked packet received. */
CC_RTO = 0x0200, /* RTO fired. */
CC_RTO_ERR = 0x0400, /* RTO fired in error. */
CC_NDUPACK = 0x0800, /* Threshold of dupack's reached. */
/*
* The highest order 8 bits (0x01000000 - 0x80000000) are reserved
* for CC algos to declare their own congestion signal types.
*/
CC_SIGPRIVMASK = 0xFF000000 /* Mask to check if sig is private. */
} ccsignal_t;
#ifdef _KERNEL
/*
* 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);
/* Return the size of the void pointer the CC needs for state */
size_t (*cc_data_sz)(void);
/*
* Init CC state for a new control block. The CC
* module may be passed a NULL ptr indicating that
* it must allocate the memory. If it is passed a
* non-null pointer it is pre-allocated memory by
* the caller and the cb_init is expected to use that memory.
* It is not expected to fail if memory is passed in and
* all currently defined modules do not.
*/
int (*cb_init)(struct cc_var *ccv, void *ptr);
/* 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, ccsignal_t type);
/* Called on detection of a congestion signal. */
void (*cong_signal)(struct cc_var *ccv, ccsignal_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);
/* Called for an additional ECN processing apart from RFC3168. */
void (*ecnpkt_handler)(struct cc_var *ccv);
/* Called when a new "round" begins, if the transport is tracking rounds. */
void (*newround)(struct cc_var *ccv, uint32_t round_cnt);
/*
* Called when a RTT sample is made (fas = flight at send, if you dont have it
* send the cwnd in).
*/
void (*rttsample)(struct cc_var *ccv, uint32_t usec_rtt, uint32_t rxtcnt, uint32_t fas);
/* Called for {get|set}sockopt() on a TCP socket with TCP_CCALGOOPT. */
int (*ctl_output)(struct cc_var *, struct sockopt *, void *);
STAILQ_ENTRY (cc_algo) entries;
u_int cc_refcount;
uint8_t flags;
};
#define CC_MODULE_BEING_REMOVED 0x01 /* The module is being removed */
/* Macro to obtain the CC algo's struct ptr. */
#define CC_ALGO(tp) ((tp)->t_cc)
/* Macro to obtain the CC algo's data ptr. */
#define CC_DATA(tp) ((tp)->t_ccv.cc_data)
/* Macro to obtain the system default CC algo's struct ptr. */
#define CC_DEFAULT_ALGO() 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)
#define CC_ALGOOPT_LIMIT 2048
/*
* These routines give NewReno behavior to the caller
* they require no state and can be used by any other CC
* module that wishes to use NewReno type behaviour (along
* with anything else they may add on, pre or post call).
*/
void newreno_cc_post_recovery(struct cc_var *);
void newreno_cc_after_idle(struct cc_var *);
void newreno_cc_cong_signal(struct cc_var *, ccsignal_t);
void newreno_cc_ack_received(struct cc_var *, ccsignal_t);
u_int newreno_cc_cwnd_on_multiplicative_decrease(struct cc_var *ccv, uint32_t mss);
u_int newreno_cc_cwnd_in_cong_avoid(struct cc_var *ccv);
u_int newreno_cc_cwnd_in_slow_start(struct cc_var *ccv);
/* Called to temporarily keep an algo from going away during change */
void cc_refer(struct cc_algo *algo);
/* Called to release the temporary hold */
void cc_release(struct cc_algo *algo);
/* Called to attach a CC algorithm to a tcpcb */
void cc_attach(struct tcpcb *, struct cc_algo *);
/* Called to detach a CC algorithm from a tcpcb */
void cc_detach(struct tcpcb *);
#endif /* _KERNEL */
#endif /* _NETINET_CC_CC_H_ */
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