/* $OpenBSD: kern_watchdog.c,v 1.6 2006/09/19 21:43:13 mk Exp $ */ /* * Copyright (c) 2003 Markus Friedl. All rights reserved. * * 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 ``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 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. */ #include <sys/param.h> #include <sys/kernel.h> #include <sys/systm.h> #include <sys/sysctl.h> #include <sys/time.h> void wdog_tickle(void *arg); void wdog_shutdown(void *arg); int (*wdog_ctl_cb)(void *, int) = NULL; void *wdog_ctl_cb_arg = NULL; int wdog_period = 0; int wdog_auto = 1; struct timeout wdog_timeout; void wdog_register(void *cb_arg, int (*cb)(void *, int)) { if (wdog_ctl_cb != NULL) return; wdog_ctl_cb = cb; wdog_ctl_cb_arg = cb_arg; timeout_set(&wdog_timeout, wdog_tickle, NULL); shutdownhook_establish(wdog_shutdown, NULL); } void wdog_tickle(void *arg) { if (wdog_ctl_cb == NULL) return; (void) (*wdog_ctl_cb)(wdog_ctl_cb_arg, wdog_period); timeout_add(&wdog_timeout, wdog_period * hz / 2); } void wdog_shutdown(void *arg) { if (wdog_ctl_cb == NULL) return; timeout_del(&wdog_timeout); (void) (*wdog_ctl_cb)(wdog_ctl_cb_arg, 0); wdog_ctl_cb = NULL; wdog_period = 0; wdog_auto = 1; } int sysctl_wdog(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { int error, period; if (wdog_ctl_cb == NULL) return (EOPNOTSUPP); switch (name[0]) { case KERN_WATCHDOG_PERIOD: period = wdog_period; error = sysctl_int(oldp, oldlenp, newp, newlen, &period); if (error) return (error); if (newp) { timeout_del(&wdog_timeout); wdog_period = (*wdog_ctl_cb)(wdog_ctl_cb_arg, period); } break; case KERN_WATCHDOG_AUTO: error = sysctl_int(oldp, oldlenp, newp, newlen, &wdog_auto); if (error) return (error); break; default: return (EINVAL); } if (wdog_auto && wdog_period > 0) { (void) (*wdog_ctl_cb)(wdog_ctl_cb_arg, wdog_period); timeout_add(&wdog_timeout, wdog_period * hz / 2); } else timeout_del(&wdog_timeout); return (error); }