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 } 150