hw/watchdog/watchdog.c

   1 /*
   2  * Virtual hardware watchdog.
   3  *
   4  * Copyright (C) 2009 Red Hat Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  *
  19  * By Richard W.M. Jones (rjones@redhat.com).
  20  */
  21
  22 #include "qemu/osdep.h"
  23 #include "qemu/option.h"
  24 #include "qemu/config-file.h"
  25 #include "qemu/queue.h"
  26 #include "qapi/error.h"
  27 #include "qapi/qapi-commands-run-state.h"
  28 #include "qapi/qapi-events-run-state.h"
  29 #include "sysemu/runstate.h"
  30 #include "sysemu/watchdog.h"
  31 #include "hw/nmi.h"
  32 #include "qemu/help_option.h"
  33 #include "trace.h"
  34
  35 static WatchdogAction watchdog_action = WATCHDOG_ACTION_RESET;
  36
  37 WatchdogAction get_watchdog_action(void)
  38 {
  39     return watchdog_action;
  40 }
  41
  42 /* This actually performs the "action" once a watchdog has expired,
  43  * ie. reboot, shutdown, exit, etc.
  44  */
  45 void watchdog_perform_action(void)
  46 {
  47     trace_watchdog_perform_action(watchdog_action);
  48
  49     switch (watchdog_action) {
  50     case WATCHDOG_ACTION_RESET:     /* same as 'system_reset' in monitor */
  51         qapi_event_send_watchdog(WATCHDOG_ACTION_RESET);
  52         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
  53         break;
  54
  55     case WATCHDOG_ACTION_SHUTDOWN:  /* same as 'system_powerdown' in monitor */
  56         qapi_event_send_watchdog(WATCHDOG_ACTION_SHUTDOWN);
  57         qemu_system_powerdown_request();
  58         break;
  59
  60     case WATCHDOG_ACTION_POWEROFF:  /* same as 'quit' command in monitor */
  61         qapi_event_send_watchdog(WATCHDOG_ACTION_POWEROFF);
  62         exit(0);
  63
  64     case WATCHDOG_ACTION_PAUSE:     /* same as 'stop' command in monitor */
  65         /* In a timer callback, when vm_stop calls qemu_clock_enable
  66          * you would get a deadlock.  Bypass the problem.
  67          */
  68         qemu_system_vmstop_request_prepare();
  69         qapi_event_send_watchdog(WATCHDOG_ACTION_PAUSE);
  70         qemu_system_vmstop_request(RUN_STATE_WATCHDOG);
  71         break;
  72
  73     case WATCHDOG_ACTION_DEBUG:
  74         qapi_event_send_watchdog(WATCHDOG_ACTION_DEBUG);
  75         fprintf(stderr, "watchdog: timer fired\n");
  76         break;
  77
  78     case WATCHDOG_ACTION_NONE:
  79         qapi_event_send_watchdog(WATCHDOG_ACTION_NONE);
  80         break;
  81
  82     case WATCHDOG_ACTION_INJECT_NMI:
  83         qapi_event_send_watchdog(WATCHDOG_ACTION_INJECT_NMI);
  84         nmi_monitor_handle(0, NULL);
  85         break;
  86
  87     default:
  88         g_assert_not_reached();
  89     }
  90 }
  91
  92 void qmp_watchdog_set_action(WatchdogAction action, Error **errp)
  93 {
  94     watchdog_action = action;
  95     trace_watchdog_set_action(watchdog_action);
  96 }