xref: /qemu/hw/watchdog/watchdog.c (revision 6f1e91f716a96651feae89dfd674b2ea3bf8e282)
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          assert(0);
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  }
97