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/* $OpenBSD: llc_timer.c,v 1.4 2003/12/10 07:22:42 itojun Exp $ */
/* $NetBSD: llc_timer.c,v 1.3 1996/02/13 22:04:57 christos Exp $ */
/*
* Copyright (C) Dirk Husemann, Computer Science Department IV,
* University of Erlangen-Nuremberg, Germany, 1990, 1991, 1992
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Dirk Husemann and the Computer Science Department (IV) of
* the University of Erlangen-Nuremberg, Germany.
*
* 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)llc_timer.c 8.1 (Berkeley) 6/10/93
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/socket.h>
#include <sys/protosw.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_llc.h>
#include <netccitt/dll.h>
#include <netccitt/llc_var.h>
/*
* Various timer values. They can be adjusted
* by patching the binary with adb if necessary.
*/
/* ISO 8802-2 timers */
int llc_n2 = LLC_N2_VALUE;
int llc_ACK_timer = LLC_ACK_TIMER;
int llc_P_timer = LLC_P_TIMER;
int llc_BUSY_timer = LLC_BUSY_TIMER;
int llc_REJ_timer = LLC_REJ_TIMER;
/* Implementation specific timers */
int llc_AGE_timer = LLC_AGE_TIMER;
int llc_DACTION_timer = LLC_DACTION_TIMER;
/*
* The timer routine. We are called every 500ms by the kernel.
* Handle the various virtual timers.
*/
void
llc_timer()
{
struct llc_linkcb *linkp;
struct llc_linkcb *nlinkp;
int timer;
int action;
int s = splimp();
/*
* All links are accessible over the doubly linked list llccb_q
*/
if (!LQEMPTY) {
/*
* A for-loop is not that great an idea as the linkp
* might get deleted if the age timer has expired ...
*/
linkp = LQFIRST;
while (LQVALID(linkp)) {
nlinkp = LQNEXT(linkp);
/*
* Check implementation specific timers first
*/
/* The delayed action/acknowledge idle timer */
switch (LLC_TIMERXPIRED(linkp,DACTION)) {
case LLC_TIMER_RUNNING:
LLC_AGETIMER(linkp,DACTION);
break;
case LLC_TIMER_EXPIRED: {
int cmdrsp;
int pollfinal;
switch (LLC_GETFLAG(linkp,DACTION)) {
case LLC_DACKCMD:
cmdrsp = LLC_CMD, pollfinal = 0;
break;
case LLC_DACKCMDPOLL:
cmdrsp = LLC_CMD, pollfinal = 1;
break;
case LLC_DACKRSP:
cmdrsp = LLC_RSP, pollfinal = 0;
break;
case LLC_DACKRSPFINAL:
cmdrsp = LLC_RSP, pollfinal = 1;
break;
default:
panic("Unexpected LLC_GETFLAG");
return;
}
llc_send(linkp, LLCFT_RR, cmdrsp, pollfinal);
LLC_STOPTIMER(linkp,DACTION);
break;
}
}
/* The link idle timer */
switch (LLC_TIMERXPIRED(linkp,AGE)) {
case LLC_TIMER_RUNNING:
LLC_AGETIMER(linkp,AGE);
break;
case LLC_TIMER_EXPIRED:
/*
* Only crunch the link when really no
* timers are running any more.
*/
if (llc_anytimersup(linkp) == 0) {
llc_dellink(linkp);
LLC_STOPTIMER(linkp,AGE);
goto gone;
} else {
LLC_STARTTIMER(linkp,AGE);
}
break;
}
/*
* Now, check all the ISO 8802-2 timers
*/
FOR_ALL_LLC_TIMERS(timer) {
action = 0;
if ((linkp->llcl_timerflags & (1<<timer)) &&
(linkp->llcl_timers[timer] == 0)) {
switch (timer) {
case LLC_ACK_SHIFT:
action = LLC_ACK_TIMER_EXPIRED;
break;
case LLC_P_SHIFT:
action = LLC_P_TIMER_EXPIRED;
break;
case LLC_BUSY_SHIFT:
action = LLC_BUSY_TIMER_EXPIRED;
break;
case LLC_REJ_SHIFT:
action = LLC_REJ_TIMER_EXPIRED;
break;
}
linkp->llcl_timerflags &= ~(1<<timer);
(void)llc_statehandler(linkp, (struct llc *)0, action, 0, 1);
} else if (linkp->llcl_timers[timer] > 0)
linkp->llcl_timers[timer]--;
}
gone: linkp = nlinkp;
}
}
splx (s);
}
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