From 0e2110d2e910e44cc7cf23fce14613e232602602 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Tue, 10 May 2022 02:32:15 +0300 Subject: kernel/reboot: Add kernel_can_power_off() Add kernel_can_power_off() helper that replaces open-coded checks of the global pm_power_off variable. This is a necessary step towards supporting chained power-off handlers. Signed-off-by: Dmitry Osipenko Signed-off-by: Rafael J. Wysocki --- kernel/reboot.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'kernel/reboot.c') diff --git a/kernel/reboot.c b/kernel/reboot.c index 7723aff4d09b..fb3f49350927 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -523,6 +523,18 @@ void do_kernel_power_off(void) atomic_notifier_call_chain(&power_off_handler_list, 0, NULL); } +/** + * 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); +} +EXPORT_SYMBOL_GPL(kernel_can_power_off); + /** * kernel_power_off - power_off the system * @@ -581,7 +593,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, /* 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); -- cgit