* this indicates whether you can reboot with ctrl-alt-del: the default is yes
*/
-int C_A_D = 1;
+static int C_A_D = 1;
struct pid *cad_pid;
EXPORT_SYMBOL(cad_pid);
enum reboot_type reboot_type = BOOT_ACPI;
int reboot_force;
+struct sys_off_handler {
+ struct notifier_block nb;
+ int (*sys_off_cb)(struct sys_off_data *data);
+ void *cb_data;
+ enum sys_off_mode mode;
+ bool blocking;
+ void *list;
+};
+
/*
- * If set, this is used for preparing the system to power off.
+ * Temporary stub that prevents linkage failure while we're in process
+ * of removing all uses of legacy pm_power_off() around the kernel.
*/
-
-void (*pm_power_off_prepare)(void);
-EXPORT_SYMBOL_GPL(pm_power_off_prepare);
+void __weak (*pm_power_off)(void);
/**
* emergency_restart - reboot the system
}
EXPORT_SYMBOL_GPL(kernel_halt);
+/*
+ * Notifier list for kernel code which wants to be called
+ * to prepare system for power off.
+ */
+static BLOCKING_NOTIFIER_HEAD(power_off_prep_handler_list);
+
+/*
+ * Notifier list for kernel code which wants to be called
+ * to power off system.
+ */
+static ATOMIC_NOTIFIER_HEAD(power_off_handler_list);
+
+static int sys_off_notify(struct notifier_block *nb,
+ unsigned long mode, void *cmd)
+{
+ struct sys_off_handler *handler;
+ struct sys_off_data data = {};
+
+ handler = container_of(nb, struct sys_off_handler, nb);
+ data.cb_data = handler->cb_data;
+ data.mode = mode;
+ data.cmd = cmd;
+
+ return handler->sys_off_cb(&data);
+}
+
+static struct sys_off_handler platform_sys_off_handler;
+
+static struct sys_off_handler *alloc_sys_off_handler(int priority)
+{
+ struct sys_off_handler *handler;
+ gfp_t flags;
+
+ /*
+ * Platforms like m68k can't allocate sys_off handler dynamically
+ * at the early boot time because memory allocator isn't available yet.
+ */
+ if (priority == SYS_OFF_PRIO_PLATFORM) {
+ handler = &platform_sys_off_handler;
+ if (handler->cb_data)
+ return ERR_PTR(-EBUSY);
+ } else {
+ if (system_state > SYSTEM_RUNNING)
+ flags = GFP_ATOMIC;
+ else
+ flags = GFP_KERNEL;
+
+ handler = kzalloc(sizeof(*handler), flags);
+ if (!handler)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return handler;
+}
+
+static void free_sys_off_handler(struct sys_off_handler *handler)
+{
+ if (handler == &platform_sys_off_handler)
+ memset(handler, 0, sizeof(*handler));
+ else
+ kfree(handler);
+}
+
+/**
+ * register_sys_off_handler - Register sys-off handler
+ * @mode: Sys-off mode
+ * @priority: Handler priority
+ * @callback: Callback function
+ * @cb_data: Callback argument
+ *
+ * Registers system power-off or restart handler that will be invoked
+ * at the step corresponding to the given sys-off mode. Handler's callback
+ * should return NOTIFY_DONE to permit execution of the next handler in
+ * the call chain or NOTIFY_STOP to break the chain (in error case for
+ * example).
+ *
+ * Multiple handlers can be registered at the default priority level.
+ *
+ * Only one handler can be registered at the non-default priority level,
+ * otherwise ERR_PTR(-EBUSY) is returned.
+ *
+ * Returns a new instance of struct sys_off_handler on success, or
+ * an ERR_PTR()-encoded error code otherwise.
+ */
+struct sys_off_handler *
+register_sys_off_handler(enum sys_off_mode mode,
+ int priority,
+ int (*callback)(struct sys_off_data *data),
+ void *cb_data)
+{
+ struct sys_off_handler *handler;
+ int err;
+
+ handler = alloc_sys_off_handler(priority);
+ if (IS_ERR(handler))
+ return handler;
+
+ switch (mode) {
+ case SYS_OFF_MODE_POWER_OFF_PREPARE:
+ handler->list = &power_off_prep_handler_list;
+ handler->blocking = true;
+ break;
+
+ case SYS_OFF_MODE_POWER_OFF:
+ handler->list = &power_off_handler_list;
+ break;
+
+ case SYS_OFF_MODE_RESTART:
+ handler->list = &restart_handler_list;
+ break;
+
+ default:
+ free_sys_off_handler(handler);
+ return ERR_PTR(-EINVAL);
+ }
+
+ handler->nb.notifier_call = sys_off_notify;
+ handler->nb.priority = priority;
+ handler->sys_off_cb = callback;
+ handler->cb_data = cb_data;
+ handler->mode = mode;
+
+ if (handler->blocking) {
+ if (priority == SYS_OFF_PRIO_DEFAULT)
+ err = blocking_notifier_chain_register(handler->list,
+ &handler->nb);
+ else
+ err = blocking_notifier_chain_register_unique_prio(handler->list,
+ &handler->nb);
+ } else {
+ if (priority == SYS_OFF_PRIO_DEFAULT)
+ err = atomic_notifier_chain_register(handler->list,
+ &handler->nb);
+ else
+ err = atomic_notifier_chain_register_unique_prio(handler->list,
+ &handler->nb);
+ }
+
+ if (err) {
+ free_sys_off_handler(handler);
+ return ERR_PTR(err);
+ }
+
+ return handler;
+}
+EXPORT_SYMBOL_GPL(register_sys_off_handler);
+
+/**
+ * unregister_sys_off_handler - Unregister sys-off handler
+ * @handler: Sys-off handler
+ *
+ * Unregisters given sys-off handler.
+ */
+void unregister_sys_off_handler(struct sys_off_handler *handler)
+{
+ int err;
+
+ if (IS_ERR_OR_NULL(handler))
+ return;
+
+ if (handler->blocking)
+ err = blocking_notifier_chain_unregister(handler->list,
+ &handler->nb);
+ else
+ err = atomic_notifier_chain_unregister(handler->list,
+ &handler->nb);
+
+ /* sanity check, shall never happen */
+ WARN_ON(err);
+
+ free_sys_off_handler(handler);
+}
+EXPORT_SYMBOL_GPL(unregister_sys_off_handler);
+
+static void devm_unregister_sys_off_handler(void *data)
+{
+ struct sys_off_handler *handler = data;
+
+ unregister_sys_off_handler(handler);
+}
+
+/**
+ * devm_register_sys_off_handler - Register sys-off handler
+ * @dev: Device that registers handler
+ * @mode: Sys-off mode
+ * @priority: Handler priority
+ * @callback: Callback function
+ * @cb_data: Callback argument
+ *
+ * Registers resource-managed sys-off handler.
+ *
+ * Returns zero on success, or error code on failure.
+ */
+int devm_register_sys_off_handler(struct device *dev,
+ enum sys_off_mode mode,
+ int priority,
+ int (*callback)(struct sys_off_data *data),
+ void *cb_data)
+{
+ struct sys_off_handler *handler;
+
+ handler = register_sys_off_handler(mode, priority, callback, cb_data);
+ if (IS_ERR(handler))
+ return PTR_ERR(handler);
+
+ return devm_add_action_or_reset(dev, devm_unregister_sys_off_handler,
+ handler);
+}
+EXPORT_SYMBOL_GPL(devm_register_sys_off_handler);
+
+/**
+ * devm_register_power_off_handler - Register power-off handler
+ * @dev: Device that registers callback
+ * @callback: Callback function
+ * @cb_data: Callback's argument
+ *
+ * Registers resource-managed sys-off handler with a default priority
+ * and using power-off mode.
+ *
+ * Returns zero on success, or error code on failure.
+ */
+int devm_register_power_off_handler(struct device *dev,
+ int (*callback)(struct sys_off_data *data),
+ void *cb_data)
+{
+ return devm_register_sys_off_handler(dev,
+ SYS_OFF_MODE_POWER_OFF,
+ SYS_OFF_PRIO_DEFAULT,
+ callback, cb_data);
+}
+EXPORT_SYMBOL_GPL(devm_register_power_off_handler);
+
+/**
+ * devm_register_restart_handler - Register restart handler
+ * @dev: Device that registers callback
+ * @callback: Callback function
+ * @cb_data: Callback's argument
+ *
+ * Registers resource-managed sys-off handler with a default priority
+ * and using restart mode.
+ *
+ * Returns zero on success, or error code on failure.
+ */
+int devm_register_restart_handler(struct device *dev,
+ int (*callback)(struct sys_off_data *data),
+ void *cb_data)
+{
+ return devm_register_sys_off_handler(dev,
+ SYS_OFF_MODE_RESTART,
+ SYS_OFF_PRIO_DEFAULT,
+ callback, cb_data);
+}
+EXPORT_SYMBOL_GPL(devm_register_restart_handler);
+
+static struct sys_off_handler *platform_power_off_handler;
+
+static int platform_power_off_notify(struct sys_off_data *data)
+{
+ void (*platform_power_power_off_cb)(void) = data->cb_data;
+
+ platform_power_power_off_cb();
+
+ return NOTIFY_DONE;
+}
+
+/**
+ * register_platform_power_off - Register platform-level power-off callback
+ * @power_off: Power-off callback
+ *
+ * Registers power-off callback that will be called as last step
+ * of the power-off sequence. This callback is expected to be invoked
+ * for the last resort. Only one platform power-off callback is allowed
+ * to be registered at a time.
+ *
+ * Returns zero on success, or error code on failure.
+ */
+int register_platform_power_off(void (*power_off)(void))
+{
+ struct sys_off_handler *handler;
+
+ handler = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF,
+ SYS_OFF_PRIO_PLATFORM,
+ platform_power_off_notify,
+ power_off);
+ if (IS_ERR(handler))
+ return PTR_ERR(handler);
+
+ platform_power_off_handler = handler;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(register_platform_power_off);
+
+/**
+ * unregister_platform_power_off - Unregister platform-level power-off callback
+ * @power_off: Power-off callback
+ *
+ * Unregisters previously registered platform power-off callback.
+ */
+void unregister_platform_power_off(void (*power_off)(void))
+{
+ if (platform_power_off_handler &&
+ platform_power_off_handler->cb_data == power_off) {
+ unregister_sys_off_handler(platform_power_off_handler);
+ platform_power_off_handler = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(unregister_platform_power_off);
+
+static int legacy_pm_power_off(struct sys_off_data *data)
+{
+ if (pm_power_off)
+ pm_power_off();
+
+ return NOTIFY_DONE;
+}
+
+static void do_kernel_power_off_prepare(void)
+{
+ blocking_notifier_call_chain(&power_off_prep_handler_list, 0, NULL);
+}
+
+/**
+ * do_kernel_power_off - Execute kernel power-off handler call chain
+ *
+ * Expected to be called as last step of the power-off sequence.
+ *
+ * Powers off the system immediately if a power-off handler function has
+ * been registered. Otherwise does nothing.
+ */
+void do_kernel_power_off(void)
+{
+ struct sys_off_handler *sys_off = NULL;
+
+ /*
+ * Register sys-off handlers for legacy PM callback. This allows
+ * legacy PM callbacks temporary co-exist with the new sys-off API.
+ *
+ * TODO: Remove legacy handlers once all legacy PM users will be
+ * switched to the sys-off based APIs.
+ */
+ if (pm_power_off)
+ sys_off = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF,
+ SYS_OFF_PRIO_DEFAULT,
+ legacy_pm_power_off, NULL);
+
+ atomic_notifier_call_chain(&power_off_handler_list, 0, NULL);
+
+ unregister_sys_off_handler(sys_off);
+}
+
+/**
+ * kernel_can_power_off - check whether system can be powered off
+ *
+ * Returns true if power-off handler is registered and system can be
+ * powered off, false otherwise.
+ */
+bool kernel_can_power_off(void)
+{
+ return !atomic_notifier_call_chain_is_empty(&power_off_handler_list) ||
+ pm_power_off;
+}
+EXPORT_SYMBOL_GPL(kernel_can_power_off);
+
/**
* kernel_power_off - power_off the system
*
void kernel_power_off(void)
{
kernel_shutdown_prepare(SYSTEM_POWER_OFF);
- if (pm_power_off_prepare)
- pm_power_off_prepare();
+ do_kernel_power_off_prepare();
migrate_to_reboot_cpu();
syscore_shutdown();
pr_emerg("Power down\n");
/* Instead of trying to make the power_off code look like
* halt when pm_power_off is not set do it the easy way.
*/
- if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
+ if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !kernel_can_power_off())
cmd = LINUX_REBOOT_CMD_HALT;
mutex_lock(&system_transition_mutex);
kill_cad_pid(SIGINT, 1);
}
-char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff";
+#define POWEROFF_CMD_PATH_LEN 256
+static char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff";
static const char reboot_cmd[] = "/sbin/reboot";
static int run_cmd(const char *cmd)
ret = run_cmd(reboot_cmd);
if (ret) {
- printk_prefer_direct_enter();
pr_warn("Failed to start orderly reboot: forcing the issue\n");
emergency_sync();
kernel_restart(NULL);
- printk_prefer_direct_exit();
}
return ret;
ret = run_cmd(poweroff_cmd);
if (ret && force) {
- printk_prefer_direct_enter();
pr_warn("Failed to start orderly shutdown: forcing the issue\n");
/*
*/
emergency_sync();
kernel_power_off();
- printk_prefer_direct_exit();
}
return ret;
*/
static void hw_failure_emergency_poweroff_func(struct work_struct *work)
{
- printk_prefer_direct_enter();
-
/*
* We have reached here after the emergency shutdown waiting period has
* expired. This means orderly_poweroff has not been able to shut off
*/
pr_emerg("Hardware protection shutdown failed. Trying emergency restart\n");
emergency_restart();
-
- printk_prefer_direct_exit();
}
static DECLARE_DELAYED_WORK(hw_failure_emergency_poweroff_work,
{
static atomic_t allow_proceed = ATOMIC_INIT(1);
- printk_prefer_direct_enter();
-
pr_emerg("HARDWARE PROTECTION shutdown (%s)\n", reason);
/* Shutdown should be initiated only once. */
if (!atomic_dec_and_test(&allow_proceed))
- goto out;
+ return;
/*
* Queue a backup emergency shutdown in the event of
*/
hw_failure_emergency_poweroff(ms_until_forced);
orderly_poweroff(true);
-out:
- printk_prefer_direct_exit();
}
EXPORT_SYMBOL_GPL(hw_protection_shutdown);
NULL,
};
+#ifdef CONFIG_SYSCTL
+static struct ctl_table kern_reboot_table[] = {
+ {
+ .procname = "poweroff_cmd",
+ .data = &poweroff_cmd,
+ .maxlen = POWEROFF_CMD_PATH_LEN,
+ .mode = 0644,
+ .proc_handler = proc_dostring,
+ },
+ {
+ .procname = "ctrl-alt-del",
+ .data = &C_A_D,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ { }
+};
+
+static void __init kernel_reboot_sysctls_init(void)
+{
+ register_sysctl_init("kernel", kern_reboot_table);
+}
+#else
+#define kernel_reboot_sysctls_init() do { } while (0)
+#endif /* CONFIG_SYSCTL */
+
static const struct attribute_group reboot_attr_group = {
.attrs = reboot_attrs,
};
return ret;
}
+ kernel_reboot_sysctls_init();
+
return 0;
}
late_initcall(reboot_ksysfs_init);
projects / linux-2.6-microblaze.git / blobdiff