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/qmp/types.h"
  27 #include "sysemu/sysemu.h"
  28 #include "sysemu/watchdog.h"
  29 #include "qapi-event.h"
  30 #include "hw/nmi.h"
  31 #include "qemu/help_option.h"
  32
  33 static int watchdog_action = WDT_RESET;
  34 static QLIST_HEAD(watchdog_list, WatchdogTimerModel) watchdog_list;
  35
  36 void watchdog_add_model(WatchdogTimerModel *model)
  37 {
  38     QLIST_INSERT_HEAD(&watchdog_list, model, entry);
  39 }
  40
  41 /* Returns:
  42  *   0 = continue
  43  *   1 = exit program with error
  44  *   2 = exit program without error
  45  */
  46 int select_watchdog(const char *p)
  47 {
  48     WatchdogTimerModel *model;
  49     QemuOpts *opts;
  50
  51     /* -watchdog ? lists available devices and exits cleanly. */
  52     if (is_help_option(p)) {
  53         QLIST_FOREACH(model, &watchdog_list, entry) {
  54             fprintf(stderr, "\t%s\t%s\n",
  55                      model->wdt_name, model->wdt_description);
  56         }
  57         return 2;
  58     }
  59
  60     QLIST_FOREACH(model, &watchdog_list, entry) {
  61         if (strcasecmp(model->wdt_name, p) == 0) {
  62             /* add the device */
  63             opts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
  64                                     &error_abort);
  65             qemu_opt_set(opts, "driver", p, &error_abort);
  66             return 0;
  67         }
  68     }
  69
  70     fprintf(stderr, "Unknown -watchdog device. Supported devices are:\n");
  71     QLIST_FOREACH(model, &watchdog_list, entry) {
  72         fprintf(stderr, "\t%s\t%s\n",
  73                  model->wdt_name, model->wdt_description);
  74     }
  75     return 1;
  76 }
  77
  78 int select_watchdog_action(const char *p)
  79 {
  80     if (strcasecmp(p, "reset") == 0)
  81         watchdog_action = WDT_RESET;
  82     else if (strcasecmp(p, "shutdown") == 0)
  83         watchdog_action = WDT_SHUTDOWN;
  84     else if (strcasecmp(p, "poweroff") == 0)
  85         watchdog_action = WDT_POWEROFF;
  86     else if (strcasecmp(p, "pause") == 0)
  87         watchdog_action = WDT_PAUSE;
  88     else if (strcasecmp(p, "debug") == 0)
  89         watchdog_action = WDT_DEBUG;
  90     else if (strcasecmp(p, "none") == 0)
  91         watchdog_action = WDT_NONE;
  92     else if (strcasecmp(p, "inject-nmi") == 0)
  93         watchdog_action = WDT_NMI;
  94     else
  95         return -1;
  96
  97     return 0;
  98 }
  99
 100 int get_watchdog_action(void)
 101 {
 102     return watchdog_action;
 103 }
 104
 105 /* This actually performs the "action" once a watchdog has expired,
 106  * ie. reboot, shutdown, exit, etc.
 107  */
 108 void watchdog_perform_action(void)
 109 {
 110     switch (watchdog_action) {
 111     case WDT_RESET:             /* same as 'system_reset' in monitor */
 112         qapi_event_send_watchdog(WATCHDOG_EXPIRATION_ACTION_RESET, &error_abort);
 113         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
 114         break;
 115
 116     case WDT_SHUTDOWN:          /* same as 'system_powerdown' in monitor */
 117         qapi_event_send_watchdog(WATCHDOG_EXPIRATION_ACTION_SHUTDOWN, &error_abort);
 118         qemu_system_powerdown_request();
 119         break;
 120
 121     case WDT_POWEROFF:          /* same as 'quit' command in monitor */
 122         qapi_event_send_watchdog(WATCHDOG_EXPIRATION_ACTION_POWEROFF, &error_abort);
 123         exit(0);
 124
 125     case WDT_PAUSE:             /* same as 'stop' command in monitor */
 126         /* In a timer callback, when vm_stop calls qemu_clock_enable
 127          * you would get a deadlock.  Bypass the problem.
 128          */
 129         qemu_system_vmstop_request_prepare();
 130         qapi_event_send_watchdog(WATCHDOG_EXPIRATION_ACTION_PAUSE, &error_abort);
 131         qemu_system_vmstop_request(RUN_STATE_WATCHDOG);
 132         break;
 133
 134     case WDT_DEBUG:
 135         qapi_event_send_watchdog(WATCHDOG_EXPIRATION_ACTION_DEBUG, &error_abort);
 136         fprintf(stderr, "watchdog: timer fired\n");
 137         break;
 138
 139     case WDT_NONE:
 140         qapi_event_send_watchdog(WATCHDOG_EXPIRATION_ACTION_NONE, &error_abort);
 141         break;
 142
 143     case WDT_NMI:
 144         qapi_event_send_watchdog(WATCHDOG_EXPIRATION_ACTION_INJECT_NMI,
 145                                  &error_abort);
 146         nmi_monitor_handle(0, NULL);
 147         break;
 148     }
 149 }