hw/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-common.h"
  23 #include "qemu-option.h"
  24 #include "qemu-config.h"
  25 #include "sys-queue.h"
  26 #include "sysemu.h"
  27 #include "hw/watchdog.h"
  28
  29 /* Possible values for action parameter. */
  30 #define WDT_RESET        1      /* Hard reset. */
  31 #define WDT_SHUTDOWN     2      /* Shutdown. */
  32 #define WDT_POWEROFF     3      /* Quit. */
  33 #define WDT_PAUSE        4      /* Pause. */
  34 #define WDT_DEBUG        5      /* Prints a message and continues running. */
  35 #define WDT_NONE         6      /* Do nothing. */
  36
  37 static int watchdog_action = WDT_RESET;
  38 static LIST_HEAD(watchdog_list, WatchdogTimerModel) watchdog_list;
  39
  40 void watchdog_add_model(WatchdogTimerModel *model)
  41 {
  42     LIST_INSERT_HEAD(&watchdog_list, model, entry);
  43 }
  44
  45 /* Returns:
  46  *   0 = continue
  47  *   1 = exit program with error
  48  *   2 = exit program without error
  49  */
  50 int select_watchdog(const char *p)
  51 {
  52     WatchdogTimerModel *model;
  53     QemuOpts *opts;
  54
  55     /* -watchdog ? lists available devices and exits cleanly. */
  56     if (strcmp(p, "?") == 0) {
  57         LIST_FOREACH(model, &watchdog_list, entry) {
  58             fprintf(stderr, "\t%s\t%s\n",
  59                      model->wdt_name, model->wdt_description);
  60         }
  61         return 2;
  62     }
  63
  64     LIST_FOREACH(model, &watchdog_list, entry) {
  65         if (strcasecmp(model->wdt_name, p) == 0) {
  66             /* add the device */
  67             opts = qemu_opts_create(&qemu_device_opts, NULL, 0);
  68             qemu_opt_set(opts, "driver", p);
  69             return 0;
  70         }
  71     }
  72
  73     fprintf(stderr, "Unknown -watchdog device. Supported devices are:\n");
  74     LIST_FOREACH(model, &watchdog_list, entry) {
  75         fprintf(stderr, "\t%s\t%s\n",
  76                  model->wdt_name, model->wdt_description);
  77     }
  78     return 1;
  79 }
  80
  81 int select_watchdog_action(const char *p)
  82 {
  83     if (strcasecmp(p, "reset") == 0)
  84         watchdog_action = WDT_RESET;
  85     else if (strcasecmp(p, "shutdown") == 0)
  86         watchdog_action = WDT_SHUTDOWN;
  87     else if (strcasecmp(p, "poweroff") == 0)
  88         watchdog_action = WDT_POWEROFF;
  89     else if (strcasecmp(p, "pause") == 0)
  90         watchdog_action = WDT_PAUSE;
  91     else if (strcasecmp(p, "debug") == 0)
  92         watchdog_action = WDT_DEBUG;
  93     else if (strcasecmp(p, "none") == 0)
  94         watchdog_action = WDT_NONE;
  95     else
  96         return -1;
  97
  98     return 0;
  99 }
 100
 101 /* This actually performs the "action" once a watchdog has expired,
 102  * ie. reboot, shutdown, exit, etc.
 103  */
 104 void watchdog_perform_action(void)
 105 {
 106     switch(watchdog_action) {
 107     case WDT_RESET:             /* same as 'system_reset' in monitor */
 108         qemu_system_reset_request();
 109         break;
 110
 111     case WDT_SHUTDOWN:          /* same as 'system_powerdown' in monitor */
 112         qemu_system_powerdown_request();
 113         break;
 114
 115     case WDT_POWEROFF:          /* same as 'quit' command in monitor */
 116         exit(0);
 117         break;
 118
 119     case WDT_PAUSE:             /* same as 'stop' command in monitor */
 120         vm_stop(0);
 121         break;
 122
 123     case WDT_DEBUG:
 124         fprintf(stderr, "watchdog: timer fired\n");
 125         break;
 126
 127     case WDT_NONE:
 128         break;
 129     }
 130 }