From f45eb74cf9936d37dd91d28ccca865daa603eaae Mon Sep 17 00:00:00 2001 From: Rafael J. Wysocki Date: Mon, 3 Nov 2008 19:01:02 +0900 Subject: [PATCH] Hibernation: Introduce system_entering_hibernation References: bnc#441721 Introduce boolean function system_entering_hibernation() returning 'true' during the last phase of hibernation, in which devices are being put into low power states and the sleep state (for example, ACPI S4) is finally entered. Some device drivers need such a function to check if the system is in the final phase of hibernation. In particular, some SATA drivers are going to use it for blacklisting systems in which the disks should not be spun down during the last phase of hibernation (the BIOS will do that anyway). Signed-off-by: Rafael J. Wysocki Signed-off-by: Tejun Heo Signed-off-by: Jeff Garzik Signed-off-by: Tejun Heo --- include/linux/suspend.h | 2 ++ kernel/power/disk.c | 10 ++++++++++ 2 files changed, 12 insertions(+) Index: linux-2.6.27/include/linux/suspend.h =================================================================== --- linux-2.6.27.orig/include/linux/suspend.h +++ linux-2.6.27/include/linux/suspend.h @@ -232,6 +232,7 @@ extern unsigned long get_safe_page(gfp_t extern void hibernation_set_ops(struct platform_hibernation_ops *ops); extern int hibernate(void); +extern bool system_entering_hibernation(void); #else /* CONFIG_HIBERNATION */ static inline int swsusp_page_is_forbidden(struct page *p) { return 0; } static inline void swsusp_set_page_free(struct page *p) {} @@ -239,6 +240,7 @@ static inline void swsusp_unset_page_fre static inline void hibernation_set_ops(struct platform_hibernation_ops *ops) {} static inline int hibernate(void) { return -ENOSYS; } +static inline bool system_entering_hibernation(void) { return false; } #endif /* CONFIG_HIBERNATION */ #ifdef CONFIG_PM_SLEEP Index: linux-2.6.27/kernel/power/disk.c =================================================================== --- linux-2.6.27.orig/kernel/power/disk.c +++ linux-2.6.27/kernel/power/disk.c @@ -71,6 +71,14 @@ void hibernation_set_ops(struct platform mutex_unlock(&pm_mutex); } +static bool entering_platform_hibernation; + +bool system_entering_hibernation(void) +{ + return entering_platform_hibernation; +} +EXPORT_SYMBOL_GPL(system_entering_hibernation); + #ifdef CONFIG_PM_DEBUG static void hibernation_debug_sleep(void) { @@ -415,6 +423,7 @@ int hibernation_platform_enter(void) if (error) goto Close; + entering_platform_hibernation = true; suspend_console(); ftrace_save = __ftrace_enabled_save(); error = device_suspend(PMSG_HIBERNATE); @@ -450,6 +459,7 @@ int hibernation_platform_enter(void) Finish: hibernation_ops->finish(); Resume_devices: + entering_platform_hibernation = false; device_resume(PMSG_RESTORE); __ftrace_enabled_restore(ftrace_save); resume_console();