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
  34 static WatchdogAction watchdog_action = WATCHDOG_ACTION_RESET;
  35 static QLIST_HEAD(, WatchdogTimerModel) watchdog_list;
  36
  37 void watchdog_add_model(WatchdogTimerModel *model)
  38 {
  39     QLIST_INSERT_HEAD(&watchdog_list, model, entry);
  40 }
  41
  42 /* Returns:
  43  *   0 = continue
  44  *   1 = exit program with error
  45  *   2 = exit program without error
  46  */
  47 int select_watchdog(const char *p)
  48 {
  49     WatchdogTimerModel *model;
  50     QemuOpts *opts;
  51
  52     /* -watchdog ? lists available devices and exits cleanly. */
  53     if (is_help_option(p)) {
  54         QLIST_FOREACH(model, &watchdog_list, entry) {
  55             fprintf(stderr, "\t%s\t%s\n",
  56                      model->wdt_name, model->wdt_description);
  57         }
  58         return 2;
  59     }
  60
  61     QLIST_FOREACH(model, &watchdog_list, entry) {
  62         if (strcasecmp(model->wdt_name, p) == 0) {
  63             /* add the device */
  64             opts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
  65                                     &error_abort);
  66             qemu_opt_set(opts, "driver", p, &error_abort);
  67             return 0;
  68         }
  69     }
  70
  71     fprintf(stderr, "Unknown -watchdog device. Supported devices are:\n");
  72     QLIST_FOREACH(model, &watchdog_list, entry) {
  73         fprintf(stderr, "\t%s\t%s\n",
  74                  model->wdt_name, model->wdt_description);
  75     }
  76     return 1;
  77 }
  78
  79 int select_watchdog_action(const char *p)
  80 {
  81     int action;
  82     char *qapi_value;
  83
  84     qapi_value = g_ascii_strdown(p, -1);
  85     action = qapi_enum_parse(&WatchdogAction_lookup, qapi_value, -1, NULL);
  86     g_free(qapi_value);
  87     if (action < 0)
  88         return -1;
  89     qmp_watchdog_set_action(action, &error_abort);
  90     return 0;
  91 }
  92
  93 WatchdogAction get_watchdog_action(void)
  94 {
  95     return watchdog_action;
  96 }
  97
  98 /* This actually performs the "action" once a watchdog has expired,
  99  * ie. reboot, shutdown, exit, etc.
 100  */
 101 void watchdog_perform_action(void)
 102 {
 103     switch (watchdog_action) {
 104     case WATCHDOG_ACTION_RESET:     /* same as 'system_reset' in monitor */
 105         qapi_event_send_watchdog(WATCHDOG_ACTION_RESET);
 106         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
 107         break;
 108
 109     case WATCHDOG_ACTION_SHUTDOWN:  /* same as 'system_powerdown' in monitor */
 110         qapi_event_send_watchdog(WATCHDOG_ACTION_SHUTDOWN);
 111         qemu_system_powerdown_request();
 112         break;
 113
 114     case WATCHDOG_ACTION_POWEROFF:  /* same as 'quit' command in monitor */
 115         qapi_event_send_watchdog(WATCHDOG_ACTION_POWEROFF);
 116         exit(0);
 117
 118     case WATCHDOG_ACTION_PAUSE:     /* same as 'stop' command in monitor */
 119         /* In a timer callback, when vm_stop calls qemu_clock_enable
 120          * you would get a deadlock.  Bypass the problem.
 121          */
 122         qemu_system_vmstop_request_prepare();
 123         qapi_event_send_watchdog(WATCHDOG_ACTION_PAUSE);
 124         qemu_system_vmstop_request(RUN_STATE_WATCHDOG);
 125         break;
 126
 127     case WATCHDOG_ACTION_DEBUG:
 128         qapi_event_send_watchdog(WATCHDOG_ACTION_DEBUG);
 129         fprintf(stderr, "watchdog: timer fired\n");
 130         break;
 131
 132     case WATCHDOG_ACTION_NONE:
 133         qapi_event_send_watchdog(WATCHDOG_ACTION_NONE);
 134         break;
 135
 136     case WATCHDOG_ACTION_INJECT_NMI:
 137         qapi_event_send_watchdog(WATCHDOG_ACTION_INJECT_NMI);
 138         nmi_monitor_handle(0, NULL);
 139         break;
 140
 141     default:
 142         assert(0);
 143     }
 144 }
 145
 146 void qmp_watchdog_set_action(WatchdogAction action, Error **errp)
 147 {
 148     watchdog_action = action;
 149 }