diff options
Diffstat (limited to 'kernel/power')
| -rw-r--r-- | kernel/power/Kconfig | 4 | ||||
| -rw-r--r-- | kernel/power/Makefile | 5 | ||||
| -rw-r--r-- | kernel/power/hibernate.c (renamed from kernel/power/disk.c) | 59 | ||||
| -rw-r--r-- | kernel/power/hibernate_nvs.c | 135 | ||||
| -rw-r--r-- | kernel/power/main.c | 526 | ||||
| -rw-r--r-- | kernel/power/power.h | 25 | ||||
| -rw-r--r-- | kernel/power/poweroff.c | 2 | ||||
| -rw-r--r-- | kernel/power/process.c | 5 | ||||
| -rw-r--r-- | kernel/power/snapshot.c | 80 | ||||
| -rw-r--r-- | kernel/power/suspend.c | 300 | ||||
| -rw-r--r-- | kernel/power/suspend_test.c | 187 | ||||
| -rw-r--r-- | kernel/power/swsusp.c | 198 |
12 files changed, 755 insertions, 771 deletions
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index 23bd4daeb96..72067cbdb37 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -116,9 +116,13 @@ config SUSPEND_FREEZER Turning OFF this setting is NOT recommended! If in doubt, say Y. +config HIBERNATION_NVS + bool + config HIBERNATION bool "Hibernation (aka 'suspend to disk')" depends on PM && SWAP && ARCH_HIBERNATION_POSSIBLE + select HIBERNATION_NVS if HAS_IOMEM ---help--- Enable the suspend to disk (STD) functionality, which is usually called "hibernation" in user interfaces. STD checkpoints the diff --git a/kernel/power/Makefile b/kernel/power/Makefile index 720ea4f781b..c3b81c30e5d 100644 --- a/kernel/power/Makefile +++ b/kernel/power/Makefile @@ -6,6 +6,9 @@ endif obj-$(CONFIG_PM) += main.o obj-$(CONFIG_PM_SLEEP) += console.o obj-$(CONFIG_FREEZER) += process.o -obj-$(CONFIG_HIBERNATION) += swsusp.o disk.o snapshot.o swap.o user.o +obj-$(CONFIG_SUSPEND) += suspend.o +obj-$(CONFIG_PM_TEST_SUSPEND) += suspend_test.o +obj-$(CONFIG_HIBERNATION) += swsusp.o hibernate.o snapshot.o swap.o user.o +obj-$(CONFIG_HIBERNATION_NVS) += hibernate_nvs.o obj-$(CONFIG_MAGIC_SYSRQ) += poweroff.o diff --git a/kernel/power/disk.c b/kernel/power/hibernate.c index e71ca9cd81b..81d2e746489 100644 --- a/kernel/power/disk.c +++ b/kernel/power/hibernate.c @@ -1,12 +1,12 @@ /* - * kernel/power/disk.c - Suspend-to-disk support. + * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support. * * Copyright (c) 2003 Patrick Mochel * Copyright (c) 2003 Open Source Development Lab * Copyright (c) 2004 Pavel Machek <pavel@suse.cz> + * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc. * * This file is released under the GPLv2. - * */ #include <linux/suspend.h> @@ -215,19 +215,17 @@ static int create_image(int platform_mode) if (error) return error; - device_pm_lock(); - - /* At this point, device_suspend() has been called, but *not* - * device_power_down(). We *must* call device_power_down() now. + /* At this point, dpm_suspend_start() has been called, but *not* + * dpm_suspend_noirq(). We *must* call dpm_suspend_noirq() now. * Otherwise, drivers for some devices (e.g. interrupt controllers) * become desynchronized with the actual state of the hardware * at resume time, and evil weirdness ensues. */ - error = device_power_down(PMSG_FREEZE); + error = dpm_suspend_noirq(PMSG_FREEZE); if (error) { printk(KERN_ERR "PM: Some devices failed to power down, " "aborting hibernation\n"); - goto Unlock; + return error; } error = platform_pre_snapshot(platform_mode); @@ -241,9 +239,9 @@ static int create_image(int platform_mode) local_irq_disable(); - sysdev_suspend(PMSG_FREEZE); + error = sysdev_suspend(PMSG_FREEZE); if (error) { - printk(KERN_ERR "PM: Some devices failed to power down, " + printk(KERN_ERR "PM: Some system devices failed to power down, " "aborting hibernation\n"); goto Enable_irqs; } @@ -264,7 +262,7 @@ static int create_image(int platform_mode) Power_up: sysdev_resume(); - /* NOTE: device_power_up() is just a resume() for devices + /* NOTE: dpm_resume_noirq() is just a resume() for devices * that suspended with irqs off ... no overall powerup. */ @@ -277,12 +275,9 @@ static int create_image(int platform_mode) Platform_finish: platform_finish(platform_mode); - device_power_up(in_suspend ? + dpm_resume_noirq(in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); - Unlock: - device_pm_unlock(); - return error; } @@ -309,7 +304,7 @@ int hibernation_snapshot(int platform_mode) goto Close; suspend_console(); - error = device_suspend(PMSG_FREEZE); + error = dpm_suspend_start(PMSG_FREEZE); if (error) goto Recover_platform; @@ -320,7 +315,7 @@ int hibernation_snapshot(int platform_mode) /* Control returns here after successful restore */ Resume_devices: - device_resume(in_suspend ? + dpm_resume_end(in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); resume_console(); Close: @@ -344,13 +339,11 @@ static int resume_target_kernel(bool platform_mode) { int error; - device_pm_lock(); - - error = device_power_down(PMSG_QUIESCE); + error = dpm_suspend_noirq(PMSG_QUIESCE); if (error) { printk(KERN_ERR "PM: Some devices failed to power down, " "aborting resume\n"); - goto Unlock; + return error; } error = platform_pre_restore(platform_mode); @@ -401,10 +394,7 @@ static int resume_target_kernel(bool platform_mode) Cleanup: platform_restore_cleanup(platform_mode); - device_power_up(PMSG_RECOVER); - - Unlock: - device_pm_unlock(); + dpm_resume_noirq(PMSG_RECOVER); return error; } @@ -424,10 +414,10 @@ int hibernation_restore(int platform_mode) pm_prepare_console(); suspend_console(); - error = device_suspend(PMSG_QUIESCE); + error = dpm_suspend_start(PMSG_QUIESCE); if (!error) { error = resume_target_kernel(platform_mode); - device_resume(PMSG_RECOVER); + dpm_resume_end(PMSG_RECOVER); } resume_console(); pm_restore_console(); @@ -457,18 +447,16 @@ int hibernation_platform_enter(void) entering_platform_hibernation = true; suspend_console(); - error = device_suspend(PMSG_HIBERNATE); + error = dpm_suspend_start(PMSG_HIBERNATE); if (error) { if (hibernation_ops->recover) hibernation_ops->recover(); goto Resume_devices; } - device_pm_lock(); - - error = device_power_down(PMSG_HIBERNATE); + error = dpm_suspend_noirq(PMSG_HIBERNATE); if (error) - goto Unlock; + goto Resume_devices; error = hibernation_ops->prepare(); if (error) @@ -491,14 +479,11 @@ int hibernation_platform_enter(void) Platofrm_finish: hibernation_ops->finish(); - device_power_up(PMSG_RESTORE); - - Unlock: - device_pm_unlock(); + dpm_suspend_noirq(PMSG_RESTORE); Resume_devices: entering_platform_hibernation = false; - device_resume(PMSG_RESTORE); + dpm_resume_end(PMSG_RESTORE); resume_console(); Close: diff --git a/kernel/power/hibernate_nvs.c b/kernel/power/hibernate_nvs.c new file mode 100644 index 00000000000..39ac698ef83 --- /dev/null +++ b/kernel/power/hibernate_nvs.c @@ -0,0 +1,135 @@ +/* + * linux/kernel/power/hibernate_nvs.c - Routines for handling NVS memory + * + * Copyright (C) 2008,2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * + * This file is released under the GPLv2. + */ + +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/mm.h> +#include <linux/suspend.h> + +/* + * Platforms, like ACPI, may want us to save some memory used by them during + * hibernation and to restore the contents of this memory during the subsequent + * resume. The code below implements a mechanism allowing us to do that. + */ + +struct nvs_page { + unsigned long phys_start; + unsigned int size; + void *kaddr; + void *data; + struct list_head node; +}; + +static LIST_HEAD(nvs_list); + +/** + * hibernate_nvs_register - register platform NVS memory region to save + * @start - physical address of the region + * @size - size of the region + * + * The NVS region need not be page-aligned (both ends) and we arrange + * things so that the data from page-aligned addresses in this region will + * be copied into separate RAM pages. + */ +int hibernate_nvs_register(unsigned long start, unsigned long size) +{ + struct nvs_page *entry, *next; + + while (size > 0) { + unsigned int nr_bytes; + + entry = kzalloc(sizeof(struct nvs_page), GFP_KERNEL); + if (!entry) + goto Error; + + list_add_tail(&entry->node, &nvs_list); + entry->phys_start = start; + nr_bytes = PAGE_SIZE - (start & ~PAGE_MASK); + entry->size = (size < nr_bytes) ? size : nr_bytes; + + start += entry->size; + size -= entry->size; + } + return 0; + + Error: + list_for_each_entry_safe(entry, next, &nvs_list, node) { + list_del(&entry->node); + kfree(entry); + } + return -ENOMEM; +} + +/** + * hibernate_nvs_free - free data pages allocated for saving NVS regions + */ +void hibernate_nvs_free(void) +{ + struct nvs_page *entry; + + list_for_each_entry(entry, &nvs_list, node) + if (entry->data) { + free_page((unsigned long)entry->data); + entry->data = NULL; + if (entry->kaddr) { + iounmap(entry->kaddr); + entry->kaddr = NULL; + } + } +} + +/** + * hibernate_nvs_alloc - allocate memory necessary for saving NVS regions + */ +int hibernate_nvs_alloc(void) +{ + struct nvs_page *entry; + + list_for_each_entry(entry, &nvs_list, node) { + entry->data = (void *)__get_free_page(GFP_KERNEL); + if (!entry->data) { + hibernate_nvs_free(); + return -ENOMEM; + } + } + return 0; +} + +/** + * hibernate_nvs_save - save NVS memory regions + */ +void hibernate_nvs_save(void) +{ + struct nvs_page *entry; + + printk(KERN_INFO "PM: Saving platform NVS memory\n"); + + list_for_each_entry(entry, &nvs_list, node) + if (entry->data) { + entry->kaddr = ioremap(entry->phys_start, entry->size); + memcpy(entry->data, entry->kaddr, entry->size); + } +} + +/** + * hibernate_nvs_restore - restore NVS memory regions + * + * This function is going to be called with interrupts disabled, so it + * cannot iounmap the virtual addresses used to access the NVS region. + */ +void hibernate_nvs_restore(void) +{ + struct nvs_page *entry; + + printk(KERN_INFO "PM: Restoring platform NVS memory\n"); + + list_for_each_entry(entry, &nvs_list, node) + if (entry->data) + memcpy(entry->kaddr, entry->data, entry->size); +} diff --git a/kernel/power/main.c b/kernel/power/main.c index f99ed6a75ea..f710e36930c 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -8,20 +8,9 @@ * */ -#include <linux/module.h> -#include <linux/suspend.h> #include <linux/kobject.h> #include <linux/string.h> -#include <linux/delay.h> -#include <linux/errno.h> -#include <linux/kmod.h> -#include <linux/init.h> -#include <linux/console.h> -#include <linux/cpu.h> #include <linux/resume-trace.h> -#include <linux/freezer.h> -#include <linux/vmstat.h> -#include <linux/syscalls.h> #include "power.h" @@ -119,378 +108,6 @@ power_attr(pm_test); #endif /* CONFIG_PM_SLEEP */ -#ifdef CONFIG_SUSPEND - -static int suspend_test(int level) -{ -#ifdef CONFIG_PM_DEBUG - if (pm_test_level == level) { - printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); - mdelay(5000); - return 1; - } -#endif /* !CONFIG_PM_DEBUG */ - return 0; -} - -#ifdef CONFIG_PM_TEST_SUSPEND - -/* - * We test the system suspend code by setting an RTC wakealarm a short - * time in the future, then suspending. Suspending the devices won't - * normally take long ... some systems only need a few milliseconds. - * - * The time it takes is system-specific though, so when we test this - * during system bootup we allow a LOT of time. - */ -#define TEST_SUSPEND_SECONDS 5 - -static unsigned long suspend_test_start_time; - -static void suspend_test_start(void) -{ - /* FIXME Use better timebase than "jiffies", ideally a clocksource. - * What we want is a hardware counter that will work correctly even - * during the irqs-are-off stages of the suspend/resume cycle... - */ - suspend_test_start_time = jiffies; -} - -static void suspend_test_finish(const char *label) -{ - long nj = jiffies - suspend_test_start_time; - unsigned msec; - - msec = jiffies_to_msecs(abs(nj)); - pr_info("PM: %s took %d.%03d seconds\n", label, - msec / 1000, msec % 1000); - - /* Warning on suspend means the RTC alarm period needs to be - * larger -- the system was sooo slooowwww to suspend that the - * alarm (should have) fired before the system went to sleep! - * - * Warning on either suspend or resume also means the system - * has some performance issues. The stack dump of a WARN_ON - * is more likely to get the right attention than a printk... - */ - WARN(msec > (TEST_SUSPEND_SECONDS * 1000), "Component: %s\n", label); -} - -#else - -static void suspend_test_start(void) -{ -} - -static void suspend_test_finish(const char *label) -{ -} - -#endif - -/* This is just an arbitrary number */ -#define FREE_PAGE_NUMBER (100) - -static struct platform_suspend_ops *suspend_ops; - -/** - * suspend_set_ops - Set the global suspend method table. - * @ops: Pointer to ops structure. - */ - -void suspend_set_ops(struct platform_suspend_ops *ops) -{ - mutex_lock(&pm_mutex); - suspend_ops = ops; - mutex_unlock(&pm_mutex); -} - -/** - * suspend_valid_only_mem - generic memory-only valid callback - * - * Platform drivers that implement mem suspend only and only need - * to check for that in their .valid callback can use this instead - * of rolling their own .valid callback. - */ -int suspend_valid_only_mem(suspend_state_t state) -{ - return state == PM_SUSPEND_MEM; -} - -/** - * suspend_prepare - Do prep work before entering low-power state. - * - * This is common code that is called for each state that we're entering. - * Run suspend notifiers, allocate a console and stop all processes. - */ -static int suspend_prepare(void) -{ - int error; - unsigned int free_pages; - - if (!suspend_ops || !suspend_ops->enter) - return -EPERM; - - pm_prepare_console(); - - error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); - if (error) - goto Finish; - - error = usermodehelper_disable(); - if (error) - goto Finish; - - if (suspend_freeze_processes()) { - error = -EAGAIN; - goto Thaw; - } - - free_pages = global_page_state(NR_FREE_PAGES); - if (free_pages < FREE_PAGE_NUMBER) { - pr_debug("PM: free some memory\n"); - shrink_all_memory(FREE_PAGE_NUMBER - free_pages); - if (nr_free_pages() < FREE_PAGE_NUMBER) { - error = -ENOMEM; - printk(KERN_ERR "PM: No enough memory\n"); - } - } - if (!error) - return 0; - - Thaw: - suspend_thaw_processes(); - usermodehelper_enable(); - Finish: - pm_notifier_call_chain(PM_POST_SUSPEND); - pm_restore_console(); - return error; -} - -/* default implementation */ -void __attribute__ ((weak)) arch_suspend_disable_irqs(void) -{ - local_irq_disable(); -} - -/* default implementation */ -void __attribute__ ((weak)) arch_suspend_enable_irqs(void) -{ - local_irq_enable(); -} - -/** - * suspend_enter - enter the desired system sleep state. - * @state: state to enter - * - * This function should be called after devices have been suspended. - */ -static int suspend_enter(suspend_state_t state) -{ - int error; - - device_pm_lock(); - - if (suspend_ops->prepare) { - error = suspend_ops->prepare(); - if (error) - goto Done; - } - - error = device_power_down(PMSG_SUSPEND); - if (error) { - printk(KERN_ERR "PM: Some devices failed to power down\n"); - goto Platfrom_finish; - } - - if (suspend_ops->prepare_late) { - error = suspend_ops->prepare_late(); - if (error) - goto Power_up_devices; - } - - if (suspend_test(TEST_PLATFORM)) - goto Platform_wake; - - error = disable_nonboot_cpus(); - if (error || suspend_test(TEST_CPUS)) - goto Enable_cpus; - - arch_suspend_disable_irqs(); - BUG_ON(!irqs_disabled()); - - error = sysdev_suspend(PMSG_SUSPEND); - if (!error) { - if (!suspend_test(TEST_CORE)) - error = suspend_ops->enter(state); - sysdev_resume(); - } - - arch_suspend_enable_irqs(); - BUG_ON(irqs_disabled()); - - Enable_cpus: - enable_nonboot_cpus(); - - Platform_wake: - if (suspend_ops->wake) - suspend_ops->wake(); - - Power_up_devices: - device_power_up(PMSG_RESUME); - - Platfrom_finish: - if (suspend_ops->finish) - suspend_ops->finish(); - - Done: - device_pm_unlock(); - - return error; -} - -/** - * suspend_devices_and_enter - suspend devices and enter the desired system - * sleep state. - * @state: state to enter - */ -int suspend_devices_and_enter(suspend_state_t state) -{ - int error; - - if (!suspend_ops) - return -ENOSYS; - - if (suspend_ops->begin) { - error = suspend_ops->begin(state); - if (error) - goto Close; - } - suspend_console(); - suspend_test_start(); - error = device_suspend(PMSG_SUSPEND); - if (error) { - printk(KERN_ERR "PM: Some devices failed to suspend\n"); - goto Recover_platform; - } - suspend_test_finish("suspend devices"); - if (suspend_test(TEST_DEVICES)) - goto Recover_platform; - - suspend_enter(state); - - Resume_devices: - suspend_test_start(); - device_resume(PMSG_RESUME); - suspend_test_finish("resume devices"); - resume_console(); - Close: - if (suspend_ops->end) - suspend_ops->end(); - return error; - - Recover_platform: - if (suspend_ops->recover) - suspend_ops->recover(); - goto Resume_devices; -} - -/** - * suspend_finish - Do final work before exiting suspend sequence. - * - * Call platform code to clean up, restart processes, and free the - * console that we've allocated. This is not called for suspend-to-disk. - */ -static void suspend_finish(void) -{ - suspend_thaw_processes(); - usermodehelper_enable(); - pm_notifier_call_chain(PM_POST_SUSPEND); - pm_restore_console(); -} - - - - -static const char * const pm_states[PM_SUSPEND_MAX] = { - [PM_SUSPEND_STANDBY] = "standby", - [PM_SUSPEND_MEM] = "mem", -}; - -static inline int valid_state(suspend_state_t state) -{ - /* All states need lowlevel support and need to be valid - * to the lowlevel implementation, no valid callback - * implies that none are valid. */ - if (!suspend_ops || !suspend_ops->valid || !suspend_ops->valid(state)) - return 0; - return 1; -} - - -/** - * enter_state - Do common work of entering low-power state. - * @state: pm_state structure for state we're entering. - * - * Make sure we're the only ones trying to enter a sleep state. Fail - * if someone has beat us to it, since we don't want anything weird to - * happen when we wake up. - * Then, do the setup for suspend, enter the state, and cleaup (after - * we've woken up). - */ -static int enter_state(suspend_state_t state) -{ - int error; - - if (!valid_state(state)) - return -ENODEV; - - if (!mutex_trylock(&pm_mutex)) - return -EBUSY; - - printk(KERN_INFO "PM: Syncing filesystems ... "); - sys_sync(); - printk("done.\n"); - - pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); - error = suspend_prepare(); - if (error) - goto Unlock; - - if (suspend_test(TEST_FREEZER)) - goto Finish; - - pr_debug("PM: Entering %s sleep\n", pm_states[state]); - error = suspend_devices_and_enter(state); - - Finish: - pr_debug("PM: Finishing wakeup.\n"); - suspend_finish(); - Unlock: - mutex_unlock(&pm_mutex); - return error; -} - - -/** - * pm_suspend - Externally visible function for suspending system. - * @state: Enumerated value of state to enter. - * - * Determine whether or not value is within range, get state - * structure, and enter (above). - */ - -int pm_suspend(suspend_state_t state) -{ - if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) - return enter_state(state); - return -EINVAL; -} - -EXPORT_SYMBOL(pm_suspend); - -#endif /* CONFIG_SUSPEND */ - struct kobject *power_kobj; /** @@ -503,7 +120,6 @@ struct kobject *power_kobj; * store() accepts one of those strings, translates it into the * proper enumerated value, and initiates a suspend transition. */ - static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { @@ -601,7 +217,6 @@ static struct attribute_group attr_group = { .attrs = g, }; - static int __init pm_init(void) { power_kobj = kobject_create_and_add("power", NULL); @@ -611,144 +226,3 @@ static int __init pm_init(void) } core_initcall(pm_init); - - -#ifdef CONFIG_PM_TEST_SUSPEND - -#include <linux/rtc.h> - -/* - * To test system suspend, we need a hands-off mechanism to resume the - * system. RTCs wake alarms are a common self-contained mechanism. - */ - -static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state) -{ - static char err_readtime[] __initdata = - KERN_ERR "PM: can't read %s time, err %d\n"; - static char err_wakealarm [] __initdata = - KERN_ERR "PM: can't set %s wakealarm, err %d\n"; - static char err_suspend[] __initdata = - KERN_ERR "PM: suspend test failed, error %d\n"; - static char info_test[] __initdata = - KERN_INFO "PM: test RTC wakeup from '%s' suspend\n"; - - unsigned long now; - struct rtc_wkalrm alm; - int status; - - /* this may fail if the RTC hasn't been initialized */ - status = rtc_read_time(rtc, &alm.time); - if (status < 0) { - printk(err_readtime, dev_name(&rtc->dev), status); - return; - } - rtc_tm_to_time(&alm.time, &now); - - memset(&alm, 0, sizeof alm); - rtc_time_to_tm(now + TEST_SUSPEND_SECONDS, &alm.time); - alm.enabled = true; - - status = rtc_set_alarm(rtc, &alm); - if (status < 0) { - printk(err_wakealarm, dev_name(&rtc->dev), status); - return; - } - - if (state == PM_SUSPEND_MEM) { - printk(info_test, pm_states[state]); - status = pm_suspend(state); - if (status == -ENODEV) - state = PM_SUSPEND_STANDBY; - } - if (state == PM_SUSPEND_STANDBY) { - printk(info_test, pm_states[state]); - status = pm_suspend(state); - } - if (status < 0) - printk(err_suspend, status); - - /* Some platforms can't detect that the alarm triggered the - * wakeup, or (accordingly) disable it after it afterwards. - * It's supposed to give oneshot behavior; cope. - */ - alm.enabled = false; - rtc_set_alarm(rtc, &alm); -} - -static int __init has_wakealarm(struct device *dev, void *name_ptr) -{ - struct rtc_device *candidate = to_rtc_device(dev); - - if (!candidate->ops->set_alarm) - return 0; - if (!device_may_wakeup(candidate->dev.parent)) - return 0; - - *(const char **)name_ptr = dev_name(dev); - return 1; -} - -/* - * Kernel options like "test_suspend=mem" force suspend/resume sanity tests - * at startup time. They're normally disabled, for faster boot and because - * we can't know which states really work on this particular system. - */ -static suspend_state_t test_state __initdata = PM_SUSPEND_ON; - -static char warn_bad_state[] __initdata = - KERN_WARNING "PM: can't test '%s' suspend state\n"; - -static int __init setup_test_suspend(char *value) -{ - unsigned i; - - /* "=mem" ==> "mem" */ - value++; - for (i = 0; i < PM_SUSPEND_MAX; i++) { - if (!pm_states[i]) - continue; - if (strcmp(pm_states[i], value) != 0) - continue; - test_state = (__force suspend_state_t) i; - return 0; - } - printk(warn_bad_state, value); - return 0; -} -__setup("test_suspend", setup_test_suspend); - -static int __init test_suspend(void) -{ - static char warn_no_rtc[] __initdata = - KERN_WARNING "PM: no wakealarm-capable RTC driver is ready\n"; - - char *pony = NULL; - struct rtc_device *rtc = NULL; - - /* PM is initialized by now; is that state testable? */ - if (test_state == PM_SUSPEND_ON) - goto done; - if (!valid_state(test_state)) { - printk(warn_bad_state, pm_states[test_state]); - goto done; - } - - /* RTCs have initialized by now too ... can we use one? */ - class_find_device(rtc_class, NULL, &pony, has_wakealarm); - if (pony) - rtc = rtc_class_open(pony); - if (!rtc) { - printk(warn_no_rtc); - goto done; - } - - /* go for it */ - test_wakealarm(rtc, test_state); - rtc_class_close(rtc); -done: - return 0; -} -late_initcall(test_suspend); - -#endif /* CONFIG_PM_TEST_SUSPEND */ diff --git a/kernel/power/power.h b/kernel/power/power.h index 46b5ec7a3af..26d5a26f82e 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -45,7 +45,7 @@ static inline char *check_image_kernel(struct swsusp_info *info) */ #define SPARE_PAGES ((1024 * 1024) >> PAGE_SHIFT) -/* kernel/power/disk.c */ +/* kernel/power/hibernate.c */ extern int hibernation_snapshot(int platform_mode); extern int hibernation_restore(int platform_mode); extern int hibernation_platform_enter(void); @@ -74,7 +74,7 @@ extern asmlinkage int swsusp_arch_resume(void); extern int create_basic_memory_bitmaps(void); extern void free_basic_memory_bitmaps(void); -extern unsigned int count_data_pages(void); +extern int swsusp_shrink_memory(void); /** * Auxiliary structure used for reading the snapshot image data and @@ -147,9 +147,8 @@ extern int swsusp_swap_in_use(void); */ #define SF_PLATFORM_MODE 1 -/* kernel/power/disk.c */ +/* kernel/power/hibernate.c */ extern int swsusp_check(void); -extern int swsusp_shrink_memory(void); extern void swsusp_free(void); extern int swsusp_read(unsigned int *flags_p); extern int swsusp_write(unsigned int flags); @@ -161,22 +160,36 @@ extern void swsusp_show_speed(struct timeval *, struct timeval *, unsigned int, char *); #ifdef CONFIG_SUSPEND -/* kernel/power/main.c */ +/* kernel/power/suspend.c */ +extern const char *const pm_states[]; + +extern bool valid_state(suspend_state_t state); extern int suspend_devices_and_enter(suspend_state_t state); +extern int enter_state(suspend_state_t state); #else /* !CONFIG_SUSPEND */ static inline int suspend_devices_and_enter(suspend_state_t state) { return -ENOSYS; } +static inline int enter_state(suspend_state_t state) { return -ENOSYS; } +static inline bool valid_state(suspend_state_t state) { return false; } #endif /* !CONFIG_SUSPEND */ +#ifdef CONFIG_PM_TEST_SUSPEND +/* kernel/power/suspend_test.c */ +extern void suspend_test_start(void); +extern void suspend_test_finish(const char *label); +#else /* !CONFIG_PM_TEST_SUSPEND */ +static inline void suspend_test_start(void) {} +static inline void suspend_test_finish(const char *label) {} +#endif /* !CONFIG_PM_TEST_SUSPEND */ + #ifdef CONFIG_PM_SLEEP /* kernel/power/main.c */ extern int pm_notifier_call_chain(unsigned long val); #endif #ifdef CONFIG_HIGHMEM -unsigned int count_highmem_pages(void); int restore_highmem(void); #else static inline unsigned int count_highmem_pages(void) { return 0; } diff --git a/kernel/power/poweroff.c b/kernel/power/poweroff.c index 97890831e1b..e8b33700627 100644 --- a/kernel/power/poweroff.c +++ b/kernel/power/poweroff.c @@ -34,7 +34,7 @@ static struct sysrq_key_op sysrq_poweroff_op = { .handler = handle_poweroff, .help_msg = "powerOff", .action_msg = "Power Off", - .enable_mask = SYSRQ_ENABLE_BOOT, + .enable_mask = SYSRQ_ENABLE_BOOT, }; static int pm_sysrq_init(void) diff --git a/kernel/power/process.c b/kernel/power/process.c index ca634019497..da2072d7381 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -117,9 +117,12 @@ int freeze_processes(void) if (error) goto Exit; printk("done."); + + oom_killer_disable(); Exit: BUG_ON(in_atomic()); printk("\n"); + return error; } @@ -145,6 +148,8 @@ static void thaw_tasks(bool nosig_only) void thaw_processes(void) { + oom_killer_enable(); + printk("Restarting tasks ... "); thaw_tasks(true); thaw_tasks(false); diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 33e2e4a819f..523a451b45d 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -39,6 +39,14 @@ static int swsusp_page_is_free(struct page *); static void swsusp_set_page_forbidden(struct page *); static void swsusp_unset_page_forbidden(struct page *); +/* + * Preferred image size in bytes (tunable via /sys/power/image_size). + * When it is set to N, swsusp will do its best to ensure the image + * size will not exceed N bytes, but if that is impossible, it will + * try to create the smallest image possible. + */ +unsigned long image_size = 500 * 1024 * 1024; + /* List of PBEs needed for restoring the pages that were allocated before * the suspend and included in the suspend image, but have also been * allocated by the "resume" kernel, so their contents cannot be written @@ -840,7 +848,7 @@ static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn) * pages. */ -unsigned int count_highmem_pages(void) +static unsigned int count_highmem_pages(void) { struct zone *zone; unsigned int n = 0; @@ -902,7 +910,7 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn) * pages. */ -unsigned int count_data_pages(void) +static unsigned int count_data_pages(void) { struct zone *zone; unsigned long pfn, max_zone_pfn; @@ -1058,6 +1066,74 @@ void swsusp_free(void) buffer = NULL; } +/** + * swsusp_shrink_memory - Try to free as much memory as needed + * + * ... but do not OOM-kill anyone + * + * Notice: all userland should be stopped before it is called, or + * livelock is possible. + */ + +#define SHRINK_BITE 10000 +static inline unsigned long __shrink_memory(long tmp) +{ + if (tmp > SHRINK_BITE) + tmp = SHRINK_BITE; + return shrink_all_memory(tmp); +} + +int swsusp_shrink_memory(void) +{ + long tmp; + struct zone *zone; + unsigned long pages = 0; + unsigned int i = 0; + char *p = "-\\|/"; + struct timeval start, stop; + + printk(KERN_INFO "PM: Shrinking memory... "); + do_gettimeofday(&start); + do { + long size, highmem_size; + + highmem_size = count_highmem_pages(); + size = count_data_pages() + PAGES_FOR_IO + SPARE_PAGES; + tmp = size; + size += highmem_size; + for_each_populated_zone(zone) { + tmp += snapshot_additional_pages(zone); + if (is_highmem(zone)) { + highmem_size -= + zone_page_state(zone, NR_FREE_PAGES); + } else { + tmp -= zone_page_state(zone, NR_FREE_PAGES); + tmp += zone->lowmem_reserve[ZONE_NORMAL]; + } + } + + if (highmem_size < 0) + highmem_size = 0; + + tmp += highmem_size; + if (tmp > 0) { + tmp = __shrink_memory(tmp); + if (!tmp) + return -ENOMEM; + pages += tmp; + } else if (size > image_size / PAGE_SIZE) { + tmp = __shrink_memory(size - (image_size / PAGE_SIZE)); + pages += tmp; + } + printk("\b%c", p[i++%4]); + } while (tmp > 0); + do_gettimeofday(&stop); + printk("\bdone (%lu pages freed)\n", pages); + swsusp_show_speed(&start, &stop, pages, "Freed"); + + return 0; +} + #ifdef CONFIG_HIGHMEM /** * count_pages_for_highmem - compute the number of non-highmem pages diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c new file mode 100644 index 00000000000..6f10dfc2d3e --- /dev/null +++ b/kernel/power/suspend.c @@ -0,0 +1,300 @@ +/* + * kernel/power/suspend.c - Suspend to RAM and standby functionality. + * + * Copyright (c) 2003 Patrick Mochel + * Copyright (c) 2003 Open Source Development Lab + * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * + * This file is released under the GPLv2. + */ + +#include <linux/string.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/console.h> +#include <linux/cpu.h> +#include <linux/syscalls.h> + +#include "power.h" + +const char *const pm_states[PM_SUSPEND_MAX] = { + [PM_SUSPEND_STANDBY] = "standby", + [PM_SUSPEND_MEM] = "mem", +}; + +static struct platform_suspend_ops *suspend_ops; + +/** + * suspend_set_ops - Set the global suspend method table. + * @ops: Pointer to ops structure. + */ +void suspend_set_ops(struct platform_suspend_ops *ops) +{ + mutex_lock(&pm_mutex); + suspend_ops = ops; + mutex_unlock(&pm_mutex); +} + +bool valid_state(suspend_state_t state) +{ + /* + * All states need lowlevel support and need to be valid to the lowlevel + * implementation, no valid callback implies that none are valid. + */ + return suspend_ops && suspend_ops->valid && suspend_ops->valid(state); +} + +/** + * suspend_valid_only_mem - generic memory-only valid callback + * + * Platform drivers that implement mem suspend only and only need + * to check for that in their .valid callback can use this instead + * of rolling their own .valid callback. + */ +int suspend_valid_only_mem(suspend_state_t state) +{ + return state == PM_SUSPEND_MEM; +} + +static int suspend_test(int level) +{ +#ifdef CONFIG_PM_DEBUG + if (pm_test_level == level) { + printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); + mdelay(5000); + return 1; + } +#endif /* !CONFIG_PM_DEBUG */ + return 0; +} + +/** + * suspend_prepare - Do prep work before entering low-power state. + * + * This is common code that is called for each state that we're entering. + * Run suspend notifiers, allocate a console and stop all processes. + */ +static int suspend_prepare(void) +{ + int error; + + if (!suspend_ops || !suspend_ops->enter) + return -EPERM; + + pm_prepare_console(); + + error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); + if (error) + goto Finish; + + error = usermodehelper_disable(); + if (error) + goto Finish; + + error = suspend_freeze_processes(); + if (!error) + return 0; + + suspend_thaw_processes(); + usermodehelper_enable(); + Finish: + pm_notifier_call_chain(PM_POST_SUSPEND); + pm_restore_console(); + return error; +} + +/* default implementation */ +void __attribute__ ((weak)) arch_suspend_disable_irqs(void) +{ + local_irq_disable(); +} + +/* default implementation */ +void __attribute__ ((weak)) arch_suspend_enable_irqs(void) +{ + local_irq_enable(); +} + +/** + * suspend_enter - enter the desired system sleep state. + * @state: state to enter + * + * This function should be called after devices have been suspended. + */ +static int suspend_enter(suspend_state_t state) +{ + int error; + + if (suspend_ops->prepare) { + error = suspend_ops->prepare(); + if (error) + return error; + } + + error = dpm_suspend_noirq(PMSG_SUSPEND); + if (error) { + printk(KERN_ERR "PM: Some devices failed to power down\n"); + goto Platfrom_finish; + } + + if (suspend_ops->prepare_late) { + error = suspend_ops->prepare_late(); + if (error) + goto Power_up_devices; + } + + if (suspend_test(TEST_PLATFORM)) + goto Platform_wake; + + error = disable_nonboot_cpus(); + if (error || suspend_test(TEST_CPUS)) + goto Enable_cpus; + + arch_suspend_disable_irqs(); + BUG_ON(!irqs_disabled()); + + error = sysdev_suspend(PMSG_SUSPEND); + if (!error) { + if (!suspend_test(TEST_CORE)) + error = suspend_ops->enter(state); + sysdev_resume(); + } + + arch_suspend_enable_irqs(); + BUG_ON(irqs_disabled()); + + Enable_cpus: + enable_nonboot_cpus(); + + Platform_wake: + if (suspend_ops->wake) + suspend_ops->wake(); + + Power_up_devices: + dpm_resume_noirq(PMSG_RESUME); + + Platfrom_finish: + if (suspend_ops->finish) + suspend_ops->finish(); + + return error; +} + +/** + * suspend_devices_and_enter - suspend devices and enter the desired system + * sleep state. + * @state: state to enter + */ +int suspend_devices_and_enter(suspend_state_t state) +{ + int error; + + if (!suspend_ops) + return -ENOSYS; + + if (suspend_ops->begin) { + error = suspend_ops->begin(state); + if (error) + goto Close; + } + suspend_console(); + suspend_test_start(); + error = dpm_suspend_start(PMSG_SUSPEND); + if (error) { + printk(KERN_ERR "PM: Some devices failed to suspend\n"); + goto Recover_platform; + } + suspend_test_finish("suspend devices"); + if (suspend_test(TEST_DEVICES)) + goto Recover_platform; + + suspend_enter(state); + + Resume_devices: + suspend_test_start(); + dpm_resume_end(PMSG_RESUME); + suspend_test_finish("resume devices"); + resume_console(); + Close: + if (suspend_ops->end) + suspend_ops->end(); + return error; + + Recover_platform: + if (suspend_ops->recover) + suspend_ops->recover(); + goto Resume_devices; +} + +/** + * suspend_finish - Do final work before exiting suspend sequence. + * + * Call platform code to clean up, restart processes, and free the + * console that we've allocated. This is not called for suspend-to-disk. + */ +static void suspend_finish(void) +{ + suspend_thaw_processes(); + usermodehelper_enable(); + pm_notifier_call_chain(PM_POST_SUSPEND); + pm_restore_console(); +} + +/** + * enter_state - Do common work of entering low-power state. + * @state: pm_state structure for state we're entering. + * + * Make sure we're the only ones trying to enter a sleep state. Fail + * if someone has beat us to it, since we don't want anything weird to + * happen when we wake up. + * Then, do the setup for suspend, enter the state, and cleaup (after + * we've woken up). + */ +int enter_state(suspend_state_t state) +{ + int error; + + if (!valid_state(state)) + return -ENODEV; + + if (!mutex_trylock(&pm_mutex)) + return -EBUSY; + + printk(KERN_INFO "PM: Syncing filesystems ... "); + sys_sync(); + printk("done.\n"); + + pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); + error = suspend_prepare(); + if (error) + goto Unlock; + + if (suspend_test(TEST_FREEZER)) + goto Finish; + + pr_debug("PM: Entering %s sleep\n", pm_states[state]); + error = suspend_devices_and_enter(state); + + Finish: + pr_debug("PM: Finishing wakeup.\n"); + suspend_finish(); + Unlock: + mutex_unlock(&pm_mutex); + return error; +} + +/** + * pm_suspend - Externally visible function for suspending system. + * @state: Enumerated value of state to enter. + * + * Determine whether or not value is within range, get state + * structure, and enter (above). + */ +int pm_suspend(suspend_state_t state) +{ + if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) + return enter_state(state); + return -EINVAL; +} +EXPORT_SYMBOL(pm_suspend); diff --git a/kernel/power/suspend_test.c b/kernel/power/suspend_test.c new file mode 100644 index 00000000000..17d8bb1acf9 --- /dev/null +++ b/kernel/power/suspend_test.c @@ -0,0 +1,187 @@ +/* + * kernel/power/suspend_test.c - Suspend to RAM and standby test facility. + * + * Copyright (c) 2009 Pavel Machek <pavel@ucw.cz> + * + * This file is released under the GPLv2. + */ + +#include <linux/init.h> +#include <linux/rtc.h> + +#include "power.h" + +/* + * We test the system suspend code by setting an RTC wakealarm a short + * time in the future, then suspending. Suspending the devices won't + * normally take long ... some systems only need a few milliseconds. + * + * The time it takes is system-specific though, so when we test this + * during system bootup we allow a LOT of time. + */ +#define TEST_SUSPEND_SECONDS 5 + +static unsigned long suspend_test_start_time; + +void suspend_test_start(void) +{ + /* FIXME Use better timebase than "jiffies", ideally a clocksource. + * What we want is a hardware counter that will work correctly even + * during the irqs-are-off stages of the suspend/resume cycle... + */ + suspend_test_start_time = jiffies; +} + +void suspend_test_finish(const char *label) +{ + long nj = jiffies - suspend_test_start_time; + unsigned msec; + + msec = jiffies_to_msecs(abs(nj)); + pr_info("PM: %s took %d.%03d seconds\n", label, + msec / 1000, msec % 1000); + + /* Warning on suspend means the RTC alarm period needs to be + * larger -- the system was sooo slooowwww to suspend that the + * alarm (should have) fired before the system went to sleep! + * + * Warning on either suspend or resume also means the system + * has some performance issues. The stack dump of a WARN_ON + * is more likely to get the right attention than a printk... + */ + WARN(msec > (TEST_SUSPEND_SECONDS * 1000), "Component: %s\n", label); +} + +/* + * To test system suspend, we need a hands-off mechanism to resume the + * system. RTCs wake alarms are a common self-contained mechanism. + */ + +static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state) +{ + static char err_readtime[] __initdata = + KERN_ERR "PM: can't read %s time, err %d\n"; + static char err_wakealarm [] __initdata = + KERN_ERR "PM: can't set %s wakealarm, err %d\n"; + static char err_suspend[] __initdata = + KERN_ERR "PM: suspend test failed, error %d\n"; + static char info_test[] __initdata = + KERN_INFO "PM: test RTC wakeup from '%s' suspend\n"; + + unsigned long now; + struct rtc_wkalrm alm; + int status; + + /* this may fail if the RTC hasn't been initialized */ + status = rtc_read_time(rtc, &alm.time); + if (status < 0) { + printk(err_readtime, dev_name(&rtc->dev), status); + return; + } + rtc_tm_to_time(&alm.time, &now); + + memset(&alm, 0, sizeof alm); + rtc_time_to_tm(now + TEST_SUSPEND_SECONDS, &alm.time); + alm.enabled = true; + + status = rtc_set_alarm(rtc, &alm); + if (status < 0) { + printk(err_wakealarm, dev_name(&rtc->dev), status); + return; + } + + if (state == PM_SUSPEND_MEM) { + printk(info_test, pm_states[state]); + status = pm_suspend(state); + if (status == -ENODEV) + state = PM_SUSPEND_STANDBY; + } + if (state == PM_SUSPEND_STANDBY) { + printk(info_test, pm_states[state]); + status = pm_suspend(state); + } + if (status < 0) + printk(err_suspend, status); + + /* Some platforms can't detect that the alarm triggered the + * wakeup, or (accordingly) disable it after it afterwards. + * It's supposed to give oneshot behavior; cope. + */ + alm.enabled = false; + rtc_set_alarm(rtc, &alm); +} + +static int __init has_wakealarm(struct device *dev, void *name_ptr) +{ + struct rtc_device *candidate = to_rtc_device(dev); + + if (!candidate->ops->set_alarm) + return 0; + if (!device_may_wakeup(candidate->dev.parent)) + return 0; + + *(const char **)name_ptr = dev_name(dev); + return 1; +} + +/* + * Kernel options like "test_suspend=mem" force suspend/resume sanity tests + * at startup time. They're normally disabled, for faster boot and because + * we can't know which states really work on this particular system. + */ +static suspend_state_t test_state __initdata = PM_SUSPEND_ON; + +static char warn_bad_state[] __initdata = + KERN_WARNING "PM: can't test '%s' suspend state\n"; + +static int __init setup_test_suspend(char *value) +{ + unsigned i; + + /* "=mem" ==> "mem" */ + value++; + for (i = 0; i < PM_SUSPEND_MAX; i++) { + if (!pm_states[i]) + continue; + if (strcmp(pm_states[i], value) != 0) + continue; + test_state = (__force suspend_state_t) i; + return 0; + } + printk(warn_bad_state, value); + return 0; +} +__setup("test_suspend", setup_test_suspend); + +static int __init test_suspend(void) +{ + static char warn_no_rtc[] __initdata = + KERN_WARNING "PM: no wakealarm-capable RTC driver is ready\n"; + + char *pony = NULL; + struct rtc_device *rtc = NULL; + + /* PM is initialized by now; is that state testable? */ + if (test_state == PM_SUSPEND_ON) + goto done; + if (!valid_state(test_state)) { + printk(warn_bad_state, pm_states[test_state]); + goto done; + } + + /* RTCs have initialized by now too ... can we use one? */ + class_find_device(rtc_class, NULL, &pony, has_wakealarm); + if (pony) + rtc = rtc_class_open(pony); + if (!rtc) { + printk(warn_no_rtc); + goto done; + } + + /* go for it */ + test_wakealarm(rtc, test_state); + rtc_class_close(rtc); +done: + return 0; +} +late_initcall(test_suspend); diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 78c35047586..6a07f4dbf2f 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -55,14 +55,6 @@ #include "power.h" -/* - * Preferred image size in bytes (tunable via /sys/power/image_size). - * When it is set to N, swsusp will do its best to ensure the image - * size will not exceed N bytes, but if that is impossible, it will - * try to create the smallest image possible. - */ -unsigned long image_size = 500 * 1024 * 1024; - int in_suspend __nosavedata = 0; /** @@ -194,193 +186,3 @@ void swsusp_show_speed(struct timeval *start, struct timeval *stop, centisecs / 100, centisecs % 100, kps / 1000, (kps % 1000) / 10); } - -/** - * swsusp_shrink_memory - Try to free as much memory as needed - * - * ... but do not OOM-kill anyone - * - * Notice: all userland should be stopped before it is called, or - * livelock is possible. - */ - -#define SHRINK_BITE 10000 -static inline unsigned long __shrink_memory(long tmp) -{ - if (tmp > SHRINK_BITE) - tmp = SHRINK_BITE; - return shrink_all_memory(tmp); -} - -int swsusp_shrink_memory(void) -{ - long tmp; - struct zone *zone; - unsigned long pages = 0; - unsigned int i = 0; - char *p = "-\\|/"; - struct timeval start, stop; - - printk(KERN_INFO "PM: Shrinking memory... "); - do_gettimeofday(&start); - do { - long size, highmem_size; - - highmem_size = count_highmem_pages(); - size = count_data_pages() + PAGES_FOR_IO + SPARE_PAGES; - tmp = size; - size += highmem_size; - for_each_populated_zone(zone) { - tmp += snapshot_additional_pages(zone); - if (is_highmem(zone)) { - highmem_size -= - zone_page_state(zone, NR_FREE_PAGES); - } else { - tmp -= zone_page_state(zone, NR_FREE_PAGES); - tmp += zone->lowmem_reserve[ZONE_NORMAL]; - } - } - - if (highmem_size < 0) - highmem_size = 0; - - tmp += highmem_size; - if (tmp > 0) { - tmp = __shrink_memory(tmp); - if (!tmp) - return -ENOMEM; - pages += tmp; - } else if (size > image_size / PAGE_SIZE) { - tmp = __shrink_memory(size - (image_size / PAGE_SIZE)); - pages += tmp; - } - printk("\b%c", p[i++%4]); - } while (tmp > 0); - do_gettimeofday(&stop); - printk("\bdone (%lu pages freed)\n", pages); - swsusp_show_speed(&start, &stop, pages, "Freed"); - - return 0; -} - -/* - * Platforms, like ACPI, may want us to save some memory used by them during - * hibernation and to restore the contents of this memory during the subsequent - * resume. The code below implements a mechanism allowing us to do that. - */ - -struct nvs_page { - unsigned long phys_start; - unsigned int size; - void *kaddr; - void *data; - struct list_head node; -}; - -static LIST_HEAD(nvs_list); - -/** - * hibernate_nvs_register - register platform NVS memory region to save - * @start - physical address of the region - * @size - size of the region - * - * The NVS region need not be page-aligned (both ends) and we arrange - * things so that the data from page-aligned addresses in this region will - * be copied into separate RAM pages. - */ -int hibernate_nvs_register(unsigned long start, unsigned long size) -{ - struct nvs_page *entry, *next; - - while (size > 0) { - unsigned int nr_bytes; - - entry = kzalloc(sizeof(struct nvs_page), GFP_KERNEL); - if (!entry) - goto Error; - - list_add_tail(&entry->node, &nvs_list); - entry->phys_start = start; - nr_bytes = PAGE_SIZE - (start & ~PAGE_MASK); - entry->size = (size < nr_bytes) ? size : nr_bytes; - - start += entry->size; - size -= entry->size; - } - return 0; - - Error: - list_for_each_entry_safe(entry, next, &nvs_list, node) { - list_del(&entry->node); - kfree(entry); - } - return -ENOMEM; -} - -/** - * hibernate_nvs_free - free data pages allocated for saving NVS regions - */ -void hibernate_nvs_free(void) -{ - struct nvs_page *entry; - - list_for_each_entry(entry, &nvs_list, node) - if (entry->data) { - free_page((unsigned long)entry->data); - entry->data = NULL; - if (entry->kaddr) { - iounmap(entry->kaddr); - entry->kaddr = NULL; - } - } -} - -/** - * hibernate_nvs_alloc - allocate memory necessary for saving NVS regions - */ -int hibernate_nvs_alloc(void) -{ - struct nvs_page *entry; - - list_for_each_entry(entry, &nvs_list, node) { - entry->data = (void *)__get_free_page(GFP_KERNEL); - if (!entry->data) { - hibernate_nvs_free(); - return -ENOMEM; - } - } - return 0; -} - -/** - * hibernate_nvs_save - save NVS memory regions - */ -void hibernate_nvs_save(void) -{ - struct nvs_page *entry; - - printk(KERN_INFO "PM: Saving platform NVS memory\n"); - - list_for_each_entry(entry, &nvs_list, node) - if (entry->data) { - entry->kaddr = ioremap(entry->phys_start, entry->size); - memcpy(entry->data, entry->kaddr, entry->size); - } -} - -/** - * hibernate_nvs_restore - restore NVS memory regions - * - * This function is going to be called with interrupts disabled, so it - * cannot iounmap the virtual addresses used to access the NVS region. - */ -void hibernate_nvs_restore(void) -{ - struct nvs_page *entry; - - printk(KERN_INFO "PM: Restoring platform NVS memory\n"); - - list_for_each_entry(entry, &nvs_list, node) - if (entry->data) - memcpy(entry->kaddr, entry->data, entry->size); -} |