diff options
Diffstat (limited to 'sys/dev/watchdog/watchdog.c')
-rw-r--r-- | sys/dev/watchdog/watchdog.c | 242 |
1 files changed, 224 insertions, 18 deletions
diff --git a/sys/dev/watchdog/watchdog.c b/sys/dev/watchdog/watchdog.c index e7edf31..71d8ecd 100644 --- a/sys/dev/watchdog/watchdog.c +++ b/sys/dev/watchdog/watchdog.c @@ -1,5 +1,8 @@ /*- * Copyright (c) 2004 Poul-Henning Kamp + * Copyright (c) 2013 iXsystems.com, + * author: Alfred Perlstein <alfred@freebsd.org> + * * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -29,21 +32,40 @@ __FBSDID("$FreeBSD$"); #include <sys/param.h> +#include <sys/types.h> #include <sys/systm.h> #include <sys/conf.h> #include <sys/uio.h> #include <sys/kernel.h> #include <sys/malloc.h> #include <sys/module.h> +#include <sys/syslog.h> #include <sys/watchdog.h> #include <sys/bus.h> #include <machine/bus.h> +#include <sys/syscallsubr.h> /* kern_clock_gettime() */ + +static int wd_set_pretimeout(int newtimeout, int disableiftoolong); +static void wd_timeout_cb(void *arg); + +static struct callout wd_pretimeo_handle; +static int wd_pretimeout; +static int wd_pretimeout_act = WD_SOFT_LOG; + +static struct callout wd_softtimeo_handle; +static int wd_softtimer; /* true = use softtimer instead of hardware + watchdog */ +static int wd_softtimeout_act = WD_SOFT_LOG; /* action for the software timeout */ + static struct cdev *wd_dev; -static volatile u_int wd_last_u; +static volatile u_int wd_last_u; /* last timeout value set by kern_do_pat */ -static int -kern_do_pat(u_int utim) +static int wd_lastpat_valid = 0; +static time_t wd_lastpat = 0; /* when the watchdog was last patted */ + +int +wdog_kern_pat(u_int utim) { int error; @@ -51,11 +73,20 @@ kern_do_pat(u_int utim) return (EINVAL); if ((utim & WD_LASTVAL) != 0) { + /* + * if WD_LASTVAL is set, fill in the bits for timeout + * from the saved value in wd_last_u. + */ MPASS((wd_last_u & ~WD_INTERVAL) == 0); utim &= ~WD_LASTVAL; utim |= wd_last_u; - } else + } else { + /* + * Otherwise save the new interval. + * This can be zero (to disable the watchdog) + */ wd_last_u = (utim & WD_INTERVAL); + } if ((utim & WD_INTERVAL) == WD_TO_NEVER) { utim = 0; @@ -65,18 +96,49 @@ kern_do_pat(u_int utim) /* Assume no watchdog available; watchdog flags success */ error = EOPNOTSUPP; } - EVENTHANDLER_INVOKE(watchdog_list, utim, &error); + if (wd_softtimer) { + if (utim == 0) { + callout_stop(&wd_softtimeo_handle); + } else { + (void) callout_reset(&wd_softtimeo_handle, + hz*utim, wd_timeout_cb, "soft"); + } + error = 0; + } else { + EVENTHANDLER_INVOKE(watchdog_list, utim, &error); + } + wd_set_pretimeout(wd_pretimeout, true); + /* + * If we were able to arm/strobe the watchdog, then + * update the last time it was strobed for WDIOC_GETTIMELEFT + */ + if (!error) { + struct timespec ts; + + error = kern_clock_gettime(curthread /* XXX */, + CLOCK_MONOTONIC_FAST, &ts); + if (!error) { + wd_lastpat = ts.tv_sec; + wd_lastpat_valid = 1; + } + } return (error); } static int -wd_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, - int flags __unused, struct thread *td) +wd_valid_act(int act) +{ + + if ((act & ~(WD_SOFT_MASK)) != 0) + return false; + return true; +} + +static int +wd_ioctl_patpat(caddr_t data) { u_int u; - if (cmd != WDIOCPATPAT) - return (ENOIOCTL); u = *(u_int *)data; if (u & ~(WD_ACTIVE | WD_PASSIVE | WD_LASTVAL | WD_INTERVAL)) return (EINVAL); @@ -89,24 +151,162 @@ wd_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, return (ENOSYS); /* XXX Not implemented yet */ u &= ~(WD_ACTIVE | WD_PASSIVE); - return (kern_do_pat(u)); + return (wdog_kern_pat(u)); } -u_int -wdog_kern_last_timeout(void) +static int +wd_get_time_left(struct thread *td, time_t *remainp) { + struct timespec ts; + int error; - return (wd_last_u); + error = kern_clock_gettime(td, CLOCK_MONOTONIC_FAST, &ts); + if (error) + return (error); + if (!wd_lastpat_valid) + return (ENOENT); + *remainp = ts.tv_sec - wd_lastpat; + return (0); } -int -wdog_kern_pat(u_int utim) +static void +wd_timeout_cb(void *arg) { + const char *type = arg; - if (utim & ~(WD_LASTVAL | WD_INTERVAL)) - return (EINVAL); +#ifdef DDB + if ((wd_pretimeout_act & WD_SOFT_DDB)) { + char kdb_why[80]; + snprintf(kdb_why, sizeof(buf), "watchdog %s timeout", type); + kdb_backtrace(); + kdb_enter(KDB_WHY_WATCHDOG, kdb_why); + } +#endif + if ((wd_pretimeout_act & WD_SOFT_LOG)) + log(LOG_EMERG, "watchdog %s-timeout, WD_SOFT_LOG", type); + if ((wd_pretimeout_act & WD_SOFT_PRINTF)) + printf("watchdog %s-timeout, WD_SOFT_PRINTF\n", type); + if ((wd_pretimeout_act & WD_SOFT_PANIC)) + panic("watchdog %s-timeout, WD_SOFT_PANIC set", type); +} + +/* + * Called to manage timeouts. + * newtimeout needs to be in the range of 0 to actual watchdog timeout. + * if 0, we disable the pre-timeout. + * otherwise we set the pre-timeout provided it's not greater than the + * current actual watchdog timeout. + */ +static int +wd_set_pretimeout(int newtimeout, int disableiftoolong) +{ + u_int utime; + + utime = wdog_kern_last_timeout(); + /* do not permit a pre-timeout >= than the timeout. */ + if (newtimeout >= utime) { + /* + * If 'disableiftoolong' then just fall through + * so as to disable the pre-watchdog + */ + if (disableiftoolong) + newtimeout = 0; + else + return EINVAL; + } + + /* disable the pre-timeout */ + if (newtimeout == 0) { + wd_pretimeout = 0; + callout_stop(&wd_pretimeo_handle); + return 0; + } + + /* We determined the value is sane, so reset the callout */ + (void) callout_reset(&wd_pretimeo_handle, hz*(utime - newtimeout), + wd_timeout_cb, "pre-timeout"); + wd_pretimeout = newtimeout; + return 0; +} - return (kern_do_pat(utim)); +static int +wd_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, + int flags __unused, struct thread *td) +{ + u_int u; + time_t timeleft; + int error; + + error = 0; + + switch (cmd) { + case WDIOC_SETSOFT: + u = *(int *)data; + /* do nothing? */ + if (u == wd_softtimer) + break; + /* If there is a pending timeout disallow this ioctl */ + if (wd_last_u != 0) { + error = EINVAL; + break; + } + wd_softtimer = u; + break; + case WDIOC_SETSOFTTIMEOUTACT: + u = *(int *)data; + if (wd_valid_act(u)) { + wd_softtimeout_act = u; + } else { + error = EINVAL; + } + break; + case WDIOC_SETPRETIMEOUTACT: + u = *(int *)data; + if (wd_valid_act(u)) { + wd_pretimeout_act = u; + } else { + error = EINVAL; + } + break; + case WDIOC_GETPRETIMEOUT: + *(int *)data = (int)wd_pretimeout; + break; + case WDIOC_SETPRETIMEOUT: + error = wd_set_pretimeout(*(int *)data, false); + break; + case WDIOC_GETTIMELEFT: + error = wd_get_time_left(td, &timeleft); + if (error) + break; + *(int *)data = (int)timeleft; + break; + case WDIOC_SETTIMEOUT: + u = *(u_int *)data; + error = wdog_kern_pat(u); + break; + case WDIOC_GETTIMEOUT: + u = wdog_kern_last_timeout(); + *(u_int *)data = u; + break; + case WDIOCPATPAT: + error = wd_ioctl_patpat(data); + break; + default: + error = ENOIOCTL; + break; + } + return (error); +} + +/* + * Return the last timeout set, this is NOT the seconds from NOW until timeout, + * rather it is the amount of seconds passed to WDIOCPATPAT/WDIOC_SETTIMEOUT. + */ +u_int +wdog_kern_last_timeout(void) +{ + + return (wd_last_u); } static struct cdevsw wd_cdevsw = { @@ -120,10 +320,16 @@ watchdog_modevent(module_t mod __unused, int type, void *data __unused) { switch(type) { case MOD_LOAD: + callout_init(&wd_pretimeo_handle, true); + callout_init(&wd_softtimeo_handle, true); wd_dev = make_dev(&wd_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, _PATH_WATCHDOG); return 0; case MOD_UNLOAD: + callout_stop(&wd_pretimeo_handle); + callout_stop(&wd_softtimeo_handle); + callout_drain(&wd_pretimeo_handle); + callout_drain(&wd_softtimeo_handle); destroy_dev(wd_dev); return 0; case MOD_SHUTDOWN: |