swwdog.c revision 1.7.32.2
1 /* $NetBSD: swwdog.c,v 1.7.32.2 2010/08/11 22:54:12 yamt Exp $ */ 2 3 /* 4 * Copyright (c) 2004, 2005 Steven M. Bellovin 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Steven M. Bellovin 18 * 4. The name of the author contributors may not be used to endorse or 19 * promote products derived from this software without specific prior 20 * written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS 23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 24 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 25 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 26 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32 * POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 __KERNEL_RCSID(0, "$NetBSD: swwdog.c,v 1.7.32.2 2010/08/11 22:54:12 yamt Exp $"); 37 38 /* 39 * 40 * Software watchdog timer 41 * 42 */ 43 #include <sys/param.h> 44 #include <sys/callout.h> 45 #include <sys/device.h> 46 #include <sys/kernel.h> 47 #include <sys/kmem.h> 48 #include <sys/reboot.h> 49 #include <sys/systm.h> 50 #include <sys/sysctl.h> 51 #include <sys/wdog.h> 52 #include <dev/sysmon/sysmonvar.h> 53 54 #include "ioconf.h" 55 56 struct swwdog_softc { 57 device_t sc_dev; 58 struct sysmon_wdog sc_smw; 59 struct callout sc_c; 60 int sc_wdog_armed; 61 }; 62 63 void swwdogattach(int); 64 65 static int swwdog_match(device_t, cfdata_t, void *); 66 static void swwdog_attach(device_t, device_t, void *); 67 static int swwdog_detach(device_t, int); 68 static bool swwdog_suspend(device_t, const pmf_qual_t *); 69 70 static int swwdog_setmode(struct sysmon_wdog *); 71 static int swwdog_tickle(struct sysmon_wdog *); 72 73 static int swwdog_arm(struct swwdog_softc *); 74 static int swwdog_disarm(struct swwdog_softc *); 75 76 static void swwdog_panic(void *); 77 78 bool swwdog_reboot = false; /* set for panic instead of reboot */ 79 80 #define SWDOG_DEFAULT 60 /* 60-second default period */ 81 82 CFATTACH_DECL_NEW(swwdog, sizeof(struct swwdog_softc), 83 swwdog_match, swwdog_attach, swwdog_detach, NULL); 84 85 static void swwdog_sysctl_setup(void); 86 static struct sysctllog *swwdog_sysctllog; 87 88 void 89 swwdogattach(int n __unused) 90 { 91 int err; 92 static struct cfdata cf; 93 94 err = config_cfattach_attach(swwdog_cd.cd_name, &swwdog_ca); 95 if (err) { 96 aprint_error("%s: couldn't register cfattach: %d\n", 97 swwdog_cd.cd_name, err); 98 config_cfdriver_detach(&swwdog_cd); 99 return; 100 } 101 102 cf.cf_name = swwdog_cd.cd_name; 103 cf.cf_atname = swwdog_cd.cd_name; 104 cf.cf_unit = 0; 105 cf.cf_fstate = FSTATE_STAR; 106 107 (void)config_attach_pseudo(&cf); 108 109 return; 110 } 111 112 static int 113 swwdog_match(device_t parent, cfdata_t data, void *aux) 114 { 115 return 1; 116 } 117 118 static void 119 swwdog_attach(device_t parent, device_t self, void *aux) 120 { 121 struct swwdog_softc *sc = device_private(self); 122 123 sc->sc_dev = self; 124 sc->sc_smw.smw_name = device_xname(self); 125 sc->sc_smw.smw_cookie = sc; 126 sc->sc_smw.smw_setmode = swwdog_setmode; 127 sc->sc_smw.smw_tickle = swwdog_tickle; 128 sc->sc_smw.smw_period = SWDOG_DEFAULT; 129 callout_init(&sc->sc_c, 0); 130 callout_setfunc(&sc->sc_c, swwdog_panic, sc); 131 132 if (sysmon_wdog_register(&sc->sc_smw) == 0) 133 aprint_normal_dev(self, "software watchdog initialized\n"); 134 else 135 aprint_error_dev(self, "unable to register software " 136 "watchdog with sysmon\n"); 137 138 if (!pmf_device_register(self, swwdog_suspend, NULL)) 139 aprint_error_dev(self, "couldn't establish power handler\n"); 140 141 swwdog_sysctl_setup(); 142 } 143 144 static int 145 swwdog_detach(device_t self, int flags) 146 { 147 struct swwdog_softc *sc = device_private(self); 148 149 swwdog_disarm(sc); 150 callout_destroy(&sc->sc_c); 151 sysctl_teardown(&swwdog_sysctllog); 152 153 return 1; 154 } 155 156 static bool 157 swwdog_suspend(device_t dev, const pmf_qual_t *qual) 158 { 159 struct swwdog_softc *sc = device_private(dev); 160 161 /* Don't allow suspend if watchdog is armed */ 162 if ((sc->sc_smw.smw_mode & WDOG_MODE_MASK) != WDOG_MODE_DISARMED) 163 return false; 164 return true; 165 } 166 167 static int 168 swwdog_setmode(struct sysmon_wdog *smw) 169 { 170 struct swwdog_softc *sc = smw->smw_cookie; 171 int error = 0; 172 173 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) { 174 error = swwdog_disarm(sc); 175 } else { 176 if (smw->smw_period == 0) 177 return EINVAL; 178 else if (smw->smw_period == WDOG_PERIOD_DEFAULT) 179 sc->sc_smw.smw_period = SWDOG_DEFAULT; 180 else 181 sc->sc_smw.smw_period = smw->smw_period; 182 error = swwdog_arm(sc); 183 } 184 return error; 185 } 186 187 static int 188 swwdog_tickle(struct sysmon_wdog *smw) 189 { 190 191 return swwdog_arm(smw->smw_cookie); 192 } 193 194 static int 195 swwdog_arm(struct swwdog_softc *sc) 196 { 197 198 callout_schedule(&sc->sc_c, sc->sc_smw.smw_period * hz); 199 return 0; 200 } 201 202 static int 203 swwdog_disarm(struct swwdog_softc *sc) 204 { 205 206 callout_stop(&sc->sc_c); 207 return 0; 208 } 209 210 static void 211 swwdog_panic(void *vsc) 212 { 213 struct swwdog_softc *sc = vsc; 214 bool do_panic; 215 216 do_panic = !swwdog_reboot; 217 swwdog_reboot = false; 218 callout_schedule(&sc->sc_c, 60 * hz); /* deliberate double-panic */ 219 220 printf("%s: %d second timer expired\n", device_xname(sc->sc_dev), 221 sc->sc_smw.smw_period); 222 223 if (do_panic) 224 panic("watchdog timer expired"); 225 else 226 cpu_reboot(0, NULL); 227 } 228 229 static void 230 swwdog_sysctl_setup(void) 231 { 232 const struct sysctlnode *me; 233 234 KASSERT(swwdog_sysctllog == NULL); 235 236 sysctl_createv(&swwdog_sysctllog, 0, NULL, &me, CTLFLAG_READWRITE, 237 CTLTYPE_NODE, "swwdog", NULL, 238 NULL, 0, NULL, 0, 239 CTL_HW, CTL_CREATE, CTL_EOL); 240 sysctl_createv(&swwdog_sysctllog, 0, NULL, NULL, CTLFLAG_READWRITE, 241 CTLTYPE_BOOL, "reboot", "reboot if timer expires", 242 NULL, 0, &swwdog_reboot, sizeof(bool), 243 CTL_HW, me->sysctl_num, CTL_CREATE, CTL_EOL); 244 } 245
Indexes created Wed Oct 15 16:09:53 GMT 2025