v4.19.13 snapshot.
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
new file mode 100644
index 0000000..3a6c2f8
--- /dev/null
+++ b/kernel/power/Kconfig
@@ -0,0 +1,300 @@
+config SUSPEND
+ bool "Suspend to RAM and standby"
+ depends on ARCH_SUSPEND_POSSIBLE
+ default y
+ ---help---
+ Allow the system to enter sleep states in which main memory is
+ powered and thus its contents are preserved, such as the
+ suspend-to-RAM state (e.g. the ACPI S3 state).
+
+config SUSPEND_FREEZER
+ bool "Enable freezer for suspend to RAM/standby" \
+ if ARCH_WANTS_FREEZER_CONTROL || BROKEN
+ depends on SUSPEND
+ default y
+ help
+ This allows you to turn off the freezer for suspend. If this is
+ done, no tasks are frozen for suspend to RAM/standby.
+
+ Turning OFF this setting is NOT recommended! If in doubt, say Y.
+
+config SUSPEND_SKIP_SYNC
+ bool "Skip kernel's sys_sync() on suspend to RAM/standby"
+ depends on SUSPEND
+ depends on EXPERT
+ help
+ Skip the kernel sys_sync() before freezing user processes.
+ Some systems prefer not to pay this cost on every invocation
+ of suspend, or they are content with invoking sync() from
+ user-space before invoking suspend. Say Y if that's your case.
+
+config HIBERNATE_CALLBACKS
+ bool
+
+config HIBERNATION
+ bool "Hibernation (aka 'suspend to disk')"
+ depends on SWAP && ARCH_HIBERNATION_POSSIBLE
+ select HIBERNATE_CALLBACKS
+ select LZO_COMPRESS
+ select LZO_DECOMPRESS
+ select CRC32
+ ---help---
+ Enable the suspend to disk (STD) functionality, which is usually
+ called "hibernation" in user interfaces. STD checkpoints the
+ system and powers it off; and restores that checkpoint on reboot.
+
+ You can suspend your machine with 'echo disk > /sys/power/state'
+ after placing resume=/dev/swappartition on the kernel command line
+ in your bootloader's configuration file.
+
+ Alternatively, you can use the additional userland tools available
+ from <http://suspend.sf.net>.
+
+ In principle it does not require ACPI or APM, although for example
+ ACPI will be used for the final steps when it is available. One
+ of the reasons to use software suspend is that the firmware hooks
+ for suspend states like suspend-to-RAM (STR) often don't work very
+ well with Linux.
+
+ It creates an image which is saved in your active swap. Upon the next
+ boot, pass the 'resume=/dev/swappartition' argument to the kernel to
+ have it detect the saved image, restore memory state from it, and
+ continue to run as before. If you do not want the previous state to
+ be reloaded, then use the 'noresume' kernel command line argument.
+ Note, however, that fsck will be run on your filesystems and you will
+ need to run mkswap against the swap partition used for the suspend.
+
+ It also works with swap files to a limited extent (for details see
+ <file:Documentation/power/swsusp-and-swap-files.txt>).
+
+ Right now you may boot without resuming and resume later but in the
+ meantime you cannot use the swap partition(s)/file(s) involved in
+ suspending. Also in this case you must not use the filesystems
+ that were mounted before the suspend. In particular, you MUST NOT
+ MOUNT any journaled filesystems mounted before the suspend or they
+ will get corrupted in a nasty way.
+
+ For more information take a look at <file:Documentation/power/swsusp.txt>.
+
+config ARCH_SAVE_PAGE_KEYS
+ bool
+
+config PM_STD_PARTITION
+ string "Default resume partition"
+ depends on HIBERNATION
+ default ""
+ ---help---
+ The default resume partition is the partition that the suspend-
+ to-disk implementation will look for a suspended disk image.
+
+ The partition specified here will be different for almost every user.
+ It should be a valid swap partition (at least for now) that is turned
+ on before suspending.
+
+ The partition specified can be overridden by specifying:
+
+ resume=/dev/<other device>
+
+ which will set the resume partition to the device specified.
+
+ Note there is currently not a way to specify which device to save the
+ suspended image to. It will simply pick the first available swap
+ device.
+
+config PM_SLEEP
+ def_bool y
+ depends on SUSPEND || HIBERNATE_CALLBACKS
+ select PM
+ select SRCU
+
+config PM_SLEEP_SMP
+ def_bool y
+ depends on SMP
+ depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE
+ depends on PM_SLEEP
+ select HOTPLUG_CPU
+
+config PM_AUTOSLEEP
+ bool "Opportunistic sleep"
+ depends on PM_SLEEP
+ default n
+ ---help---
+ Allow the kernel to trigger a system transition into a global sleep
+ state automatically whenever there are no active wakeup sources.
+
+config PM_WAKELOCKS
+ bool "User space wakeup sources interface"
+ depends on PM_SLEEP
+ default n
+ ---help---
+ Allow user space to create, activate and deactivate wakeup source
+ objects with the help of a sysfs-based interface.
+
+config PM_WAKELOCKS_LIMIT
+ int "Maximum number of user space wakeup sources (0 = no limit)"
+ range 0 100000
+ default 100
+ depends on PM_WAKELOCKS
+
+config PM_WAKELOCKS_GC
+ bool "Garbage collector for user space wakeup sources"
+ depends on PM_WAKELOCKS
+ default y
+
+config PM
+ bool "Device power management core functionality"
+ ---help---
+ Enable functionality allowing I/O devices to be put into energy-saving
+ (low power) states, for example after a specified period of inactivity
+ (autosuspended), and woken up in response to a hardware-generated
+ wake-up event or a driver's request.
+
+ Hardware support is generally required for this functionality to work
+ and the bus type drivers of the buses the devices are on are
+ responsible for the actual handling of device suspend requests and
+ wake-up events.
+
+config PM_DEBUG
+ bool "Power Management Debug Support"
+ depends on PM
+ ---help---
+ This option enables various debugging support in the Power Management
+ code. This is helpful when debugging and reporting PM bugs, like
+ suspend support.
+
+config PM_ADVANCED_DEBUG
+ bool "Extra PM attributes in sysfs for low-level debugging/testing"
+ depends on PM_DEBUG
+ ---help---
+ Add extra sysfs attributes allowing one to access some Power Management
+ fields of device objects from user space. If you are not a kernel
+ developer interested in debugging/testing Power Management, say "no".
+
+config PM_TEST_SUSPEND
+ bool "Test suspend/resume and wakealarm during bootup"
+ depends on SUSPEND && PM_DEBUG && RTC_CLASS=y
+ ---help---
+ This option will let you suspend your machine during bootup, and
+ make it wake up a few seconds later using an RTC wakeup alarm.
+ Enable this with a kernel parameter like "test_suspend=mem".
+
+ You probably want to have your system's RTC driver statically
+ linked, ensuring that it's available when this test runs.
+
+config PM_SLEEP_DEBUG
+ def_bool y
+ depends on PM_DEBUG && PM_SLEEP
+
+config DPM_WATCHDOG
+ bool "Device suspend/resume watchdog"
+ depends on PM_DEBUG && PSTORE && EXPERT
+ ---help---
+ Sets up a watchdog timer to capture drivers that are
+ locked up attempting to suspend/resume a device.
+ A detected lockup causes system panic with message
+ captured in pstore device for inspection in subsequent
+ boot session.
+
+config DPM_WATCHDOG_TIMEOUT
+ int "Watchdog timeout in seconds"
+ range 1 120
+ default 120
+ depends on DPM_WATCHDOG
+
+config PM_TRACE
+ bool
+ help
+ This enables code to save the last PM event point across
+ reboot. The architecture needs to support this, x86 for
+ example does by saving things in the RTC, see below.
+
+ The architecture specific code must provide the extern
+ functions from <linux/resume-trace.h> as well as the
+ <asm/resume-trace.h> header with a TRACE_RESUME() macro.
+
+ The way the information is presented is architecture-
+ dependent, x86 will print the information during a
+ late_initcall.
+
+config PM_TRACE_RTC
+ bool "Suspend/resume event tracing"
+ depends on PM_SLEEP_DEBUG
+ depends on X86
+ select PM_TRACE
+ ---help---
+ This enables some cheesy code to save the last PM event point in the
+ RTC across reboots, so that you can debug a machine that just hangs
+ during suspend (or more commonly, during resume).
+
+ To use this debugging feature you should attempt to suspend the
+ machine, reboot it and then run
+
+ dmesg -s 1000000 | grep 'hash matches'
+
+ CAUTION: this option will cause your machine's real-time clock to be
+ set to an invalid time after a resume.
+
+config APM_EMULATION
+ tristate "Advanced Power Management Emulation"
+ depends on SYS_SUPPORTS_APM_EMULATION
+ help
+ APM is a BIOS specification for saving power using several different
+ techniques. This is mostly useful for battery powered laptops with
+ APM compliant BIOSes. If you say Y here, the system time will be
+ reset after a RESUME operation, the /proc/apm device will provide
+ battery status information, and user-space programs will receive
+ notification of APM "events" (e.g. battery status change).
+
+ In order to use APM, you will need supporting software. For location
+ and more information, read <file:Documentation/power/apm-acpi.txt>
+ and the Battery Powered Linux mini-HOWTO, available from
+ <http://www.tldp.org/docs.html#howto>.
+
+ This driver does not spin down disk drives (see the hdparm(8)
+ manpage ("man 8 hdparm") for that), and it doesn't turn off
+ VESA-compliant "green" monitors.
+
+ Generally, if you don't have a battery in your machine, there isn't
+ much point in using this driver and you should say N. If you get
+ random kernel OOPSes or reboots that don't seem to be related to
+ anything, try disabling/enabling this option (or disabling/enabling
+ APM in your BIOS).
+
+config PM_CLK
+ def_bool y
+ depends on PM && HAVE_CLK
+
+config PM_GENERIC_DOMAINS
+ bool
+ depends on PM
+
+config WQ_POWER_EFFICIENT_DEFAULT
+ bool "Enable workqueue power-efficient mode by default"
+ depends on PM
+ default n
+ help
+ Per-cpu workqueues are generally preferred because they show
+ better performance thanks to cache locality; unfortunately,
+ per-cpu workqueues tend to be more power hungry than unbound
+ workqueues.
+
+ Enabling workqueue.power_efficient kernel parameter makes the
+ per-cpu workqueues which were observed to contribute
+ significantly to power consumption unbound, leading to measurably
+ lower power usage at the cost of small performance overhead.
+
+ This config option determines whether workqueue.power_efficient
+ is enabled by default.
+
+ If in doubt, say N.
+
+config PM_GENERIC_DOMAINS_SLEEP
+ def_bool y
+ depends on PM_SLEEP && PM_GENERIC_DOMAINS
+
+config PM_GENERIC_DOMAINS_OF
+ def_bool y
+ depends on PM_GENERIC_DOMAINS && OF
+
+config CPU_PM
+ bool
diff --git a/kernel/power/Makefile b/kernel/power/Makefile
new file mode 100644
index 0000000..a3f79f0
--- /dev/null
+++ b/kernel/power/Makefile
@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0
+
+ccflags-$(CONFIG_PM_DEBUG) := -DDEBUG
+
+KASAN_SANITIZE_snapshot.o := n
+
+obj-y += qos.o
+obj-$(CONFIG_PM) += main.o
+obj-$(CONFIG_VT_CONSOLE_SLEEP) += console.o
+obj-$(CONFIG_FREEZER) += process.o
+obj-$(CONFIG_SUSPEND) += suspend.o
+obj-$(CONFIG_PM_TEST_SUSPEND) += suspend_test.o
+obj-$(CONFIG_HIBERNATION) += hibernate.o snapshot.o swap.o user.o
+obj-$(CONFIG_PM_AUTOSLEEP) += autosleep.o
+obj-$(CONFIG_PM_WAKELOCKS) += wakelock.o
+
+obj-$(CONFIG_MAGIC_SYSRQ) += poweroff.o
diff --git a/kernel/power/autosleep.c b/kernel/power/autosleep.c
new file mode 100644
index 0000000..41e83a7
--- /dev/null
+++ b/kernel/power/autosleep.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * kernel/power/autosleep.c
+ *
+ * Opportunistic sleep support.
+ *
+ * Copyright (C) 2012 Rafael J. Wysocki <rjw@sisk.pl>
+ */
+
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/pm_wakeup.h>
+
+#include "power.h"
+
+static suspend_state_t autosleep_state;
+static struct workqueue_struct *autosleep_wq;
+/*
+ * Note: it is only safe to mutex_lock(&autosleep_lock) if a wakeup_source
+ * is active, otherwise a deadlock with try_to_suspend() is possible.
+ * Alternatively mutex_lock_interruptible() can be used. This will then fail
+ * if an auto_sleep cycle tries to freeze processes.
+ */
+static DEFINE_MUTEX(autosleep_lock);
+static struct wakeup_source *autosleep_ws;
+
+static void try_to_suspend(struct work_struct *work)
+{
+ unsigned int initial_count, final_count;
+
+ if (!pm_get_wakeup_count(&initial_count, true))
+ goto out;
+
+ mutex_lock(&autosleep_lock);
+
+ if (!pm_save_wakeup_count(initial_count) ||
+ system_state != SYSTEM_RUNNING) {
+ mutex_unlock(&autosleep_lock);
+ goto out;
+ }
+
+ if (autosleep_state == PM_SUSPEND_ON) {
+ mutex_unlock(&autosleep_lock);
+ return;
+ }
+ if (autosleep_state >= PM_SUSPEND_MAX)
+ hibernate();
+ else
+ pm_suspend(autosleep_state);
+
+ mutex_unlock(&autosleep_lock);
+
+ if (!pm_get_wakeup_count(&final_count, false))
+ goto out;
+
+ /*
+ * If the wakeup occured for an unknown reason, wait to prevent the
+ * system from trying to suspend and waking up in a tight loop.
+ */
+ if (final_count == initial_count)
+ schedule_timeout_uninterruptible(HZ / 2);
+
+ out:
+ queue_up_suspend_work();
+}
+
+static DECLARE_WORK(suspend_work, try_to_suspend);
+
+void queue_up_suspend_work(void)
+{
+ if (autosleep_state > PM_SUSPEND_ON)
+ queue_work(autosleep_wq, &suspend_work);
+}
+
+suspend_state_t pm_autosleep_state(void)
+{
+ return autosleep_state;
+}
+
+int pm_autosleep_lock(void)
+{
+ return mutex_lock_interruptible(&autosleep_lock);
+}
+
+void pm_autosleep_unlock(void)
+{
+ mutex_unlock(&autosleep_lock);
+}
+
+int pm_autosleep_set_state(suspend_state_t state)
+{
+
+#ifndef CONFIG_HIBERNATION
+ if (state >= PM_SUSPEND_MAX)
+ return -EINVAL;
+#endif
+
+ __pm_stay_awake(autosleep_ws);
+
+ mutex_lock(&autosleep_lock);
+
+ autosleep_state = state;
+
+ __pm_relax(autosleep_ws);
+
+ if (state > PM_SUSPEND_ON) {
+ pm_wakep_autosleep_enabled(true);
+ queue_up_suspend_work();
+ } else {
+ pm_wakep_autosleep_enabled(false);
+ }
+
+ mutex_unlock(&autosleep_lock);
+ return 0;
+}
+
+int __init pm_autosleep_init(void)
+{
+ autosleep_ws = wakeup_source_register("autosleep");
+ if (!autosleep_ws)
+ return -ENOMEM;
+
+ autosleep_wq = alloc_ordered_workqueue("autosleep", 0);
+ if (autosleep_wq)
+ return 0;
+
+ wakeup_source_unregister(autosleep_ws);
+ return -ENOMEM;
+}
diff --git a/kernel/power/console.c b/kernel/power/console.c
new file mode 100644
index 0000000..fcdf0e1
--- /dev/null
+++ b/kernel/power/console.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Functions for saving/restoring console.
+ *
+ * Originally from swsusp.
+ */
+
+#include <linux/console.h>
+#include <linux/vt_kern.h>
+#include <linux/kbd_kern.h>
+#include <linux/vt.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include "power.h"
+
+#define SUSPEND_CONSOLE (MAX_NR_CONSOLES-1)
+
+static int orig_fgconsole, orig_kmsg;
+
+static DEFINE_MUTEX(vt_switch_mutex);
+
+struct pm_vt_switch {
+ struct list_head head;
+ struct device *dev;
+ bool required;
+};
+
+static LIST_HEAD(pm_vt_switch_list);
+
+
+/**
+ * pm_vt_switch_required - indicate VT switch at suspend requirements
+ * @dev: device
+ * @required: if true, caller needs VT switch at suspend/resume time
+ *
+ * The different console drivers may or may not require VT switches across
+ * suspend/resume, depending on how they handle restoring video state and
+ * what may be running.
+ *
+ * Drivers can indicate support for switchless suspend/resume, which can
+ * save time and flicker, by using this routine and passing 'false' as
+ * the argument. If any loaded driver needs VT switching, or the
+ * no_console_suspend argument has been passed on the command line, VT
+ * switches will occur.
+ */
+void pm_vt_switch_required(struct device *dev, bool required)
+{
+ struct pm_vt_switch *entry, *tmp;
+
+ mutex_lock(&vt_switch_mutex);
+ list_for_each_entry(tmp, &pm_vt_switch_list, head) {
+ if (tmp->dev == dev) {
+ /* already registered, update requirement */
+ tmp->required = required;
+ goto out;
+ }
+ }
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ goto out;
+
+ entry->required = required;
+ entry->dev = dev;
+
+ list_add(&entry->head, &pm_vt_switch_list);
+out:
+ mutex_unlock(&vt_switch_mutex);
+}
+EXPORT_SYMBOL(pm_vt_switch_required);
+
+/**
+ * pm_vt_switch_unregister - stop tracking a device's VT switching needs
+ * @dev: device
+ *
+ * Remove @dev from the vt switch list.
+ */
+void pm_vt_switch_unregister(struct device *dev)
+{
+ struct pm_vt_switch *tmp;
+
+ mutex_lock(&vt_switch_mutex);
+ list_for_each_entry(tmp, &pm_vt_switch_list, head) {
+ if (tmp->dev == dev) {
+ list_del(&tmp->head);
+ kfree(tmp);
+ break;
+ }
+ }
+ mutex_unlock(&vt_switch_mutex);
+}
+EXPORT_SYMBOL(pm_vt_switch_unregister);
+
+/*
+ * There are three cases when a VT switch on suspend/resume are required:
+ * 1) no driver has indicated a requirement one way or another, so preserve
+ * the old behavior
+ * 2) console suspend is disabled, we want to see debug messages across
+ * suspend/resume
+ * 3) any registered driver indicates it needs a VT switch
+ *
+ * If none of these conditions is present, meaning we have at least one driver
+ * that doesn't need the switch, and none that do, we can avoid it to make
+ * resume look a little prettier (and suspend too, but that's usually hidden,
+ * e.g. when closing the lid on a laptop).
+ */
+static bool pm_vt_switch(void)
+{
+ struct pm_vt_switch *entry;
+ bool ret = true;
+
+ mutex_lock(&vt_switch_mutex);
+ if (list_empty(&pm_vt_switch_list))
+ goto out;
+
+ if (!console_suspend_enabled)
+ goto out;
+
+ list_for_each_entry(entry, &pm_vt_switch_list, head) {
+ if (entry->required)
+ goto out;
+ }
+
+ ret = false;
+out:
+ mutex_unlock(&vt_switch_mutex);
+ return ret;
+}
+
+void pm_prepare_console(void)
+{
+ if (!pm_vt_switch())
+ return;
+
+ orig_fgconsole = vt_move_to_console(SUSPEND_CONSOLE, 1);
+ if (orig_fgconsole < 0)
+ return;
+
+ orig_kmsg = vt_kmsg_redirect(SUSPEND_CONSOLE);
+ return;
+}
+
+void pm_restore_console(void)
+{
+ if (!pm_vt_switch())
+ return;
+
+ if (orig_fgconsole >= 0) {
+ vt_move_to_console(orig_fgconsole, 0);
+ vt_kmsg_redirect(orig_kmsg);
+ }
+}
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
new file mode 100644
index 0000000..abef759
--- /dev/null
+++ b/kernel/power/hibernate.c
@@ -0,0 +1,1234 @@
+/*
+ * 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@ucw.cz>
+ * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
+ * Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#define pr_fmt(fmt) "PM: " fmt
+
+#include <linux/export.h>
+#include <linux/suspend.h>
+#include <linux/syscalls.h>
+#include <linux/reboot.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/async.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/pm.h>
+#include <linux/nmi.h>
+#include <linux/console.h>
+#include <linux/cpu.h>
+#include <linux/freezer.h>
+#include <linux/gfp.h>
+#include <linux/syscore_ops.h>
+#include <linux/ctype.h>
+#include <linux/genhd.h>
+#include <linux/ktime.h>
+#include <trace/events/power.h>
+
+#include "power.h"
+
+
+static int nocompress;
+static int noresume;
+static int nohibernate;
+static int resume_wait;
+static unsigned int resume_delay;
+static char resume_file[256] = CONFIG_PM_STD_PARTITION;
+dev_t swsusp_resume_device;
+sector_t swsusp_resume_block;
+__visible int in_suspend __nosavedata;
+
+enum {
+ HIBERNATION_INVALID,
+ HIBERNATION_PLATFORM,
+ HIBERNATION_SHUTDOWN,
+ HIBERNATION_REBOOT,
+#ifdef CONFIG_SUSPEND
+ HIBERNATION_SUSPEND,
+#endif
+ HIBERNATION_TEST_RESUME,
+ /* keep last */
+ __HIBERNATION_AFTER_LAST
+};
+#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
+#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
+
+static int hibernation_mode = HIBERNATION_SHUTDOWN;
+
+bool freezer_test_done;
+
+static const struct platform_hibernation_ops *hibernation_ops;
+
+bool hibernation_available(void)
+{
+ return (nohibernate == 0);
+}
+
+/**
+ * hibernation_set_ops - Set the global hibernate operations.
+ * @ops: Hibernation operations to use in subsequent hibernation transitions.
+ */
+void hibernation_set_ops(const struct platform_hibernation_ops *ops)
+{
+ if (ops && !(ops->begin && ops->end && ops->pre_snapshot
+ && ops->prepare && ops->finish && ops->enter && ops->pre_restore
+ && ops->restore_cleanup && ops->leave)) {
+ WARN_ON(1);
+ return;
+ }
+ lock_system_sleep();
+ hibernation_ops = ops;
+ if (ops)
+ hibernation_mode = HIBERNATION_PLATFORM;
+ else if (hibernation_mode == HIBERNATION_PLATFORM)
+ hibernation_mode = HIBERNATION_SHUTDOWN;
+
+ unlock_system_sleep();
+}
+EXPORT_SYMBOL_GPL(hibernation_set_ops);
+
+static bool entering_platform_hibernation;
+
+bool system_entering_hibernation(void)
+{
+ return entering_platform_hibernation;
+}
+EXPORT_SYMBOL(system_entering_hibernation);
+
+#ifdef CONFIG_PM_DEBUG
+static void hibernation_debug_sleep(void)
+{
+ pr_info("hibernation debug: Waiting for 5 seconds.\n");
+ mdelay(5000);
+}
+
+static int hibernation_test(int level)
+{
+ if (pm_test_level == level) {
+ hibernation_debug_sleep();
+ return 1;
+ }
+ return 0;
+}
+#else /* !CONFIG_PM_DEBUG */
+static int hibernation_test(int level) { return 0; }
+#endif /* !CONFIG_PM_DEBUG */
+
+/**
+ * platform_begin - Call platform to start hibernation.
+ * @platform_mode: Whether or not to use the platform driver.
+ */
+static int platform_begin(int platform_mode)
+{
+ return (platform_mode && hibernation_ops) ?
+ hibernation_ops->begin() : 0;
+}
+
+/**
+ * platform_end - Call platform to finish transition to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
+ */
+static void platform_end(int platform_mode)
+{
+ if (platform_mode && hibernation_ops)
+ hibernation_ops->end();
+}
+
+/**
+ * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to prepare the system for creating a hibernate image,
+ * if so configured, and return an error code if that fails.
+ */
+
+static int platform_pre_snapshot(int platform_mode)
+{
+ return (platform_mode && hibernation_ops) ?
+ hibernation_ops->pre_snapshot() : 0;
+}
+
+/**
+ * platform_leave - Call platform to prepare a transition to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver prepare to prepare the machine for switching to the
+ * normal mode of operation.
+ *
+ * This routine is called on one CPU with interrupts disabled.
+ */
+static void platform_leave(int platform_mode)
+{
+ if (platform_mode && hibernation_ops)
+ hibernation_ops->leave();
+}
+
+/**
+ * platform_finish - Call platform to switch the system to the working state.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to switch the machine to the normal mode of
+ * operation.
+ *
+ * This routine must be called after platform_prepare().
+ */
+static void platform_finish(int platform_mode)
+{
+ if (platform_mode && hibernation_ops)
+ hibernation_ops->finish();
+}
+
+/**
+ * platform_pre_restore - Prepare for hibernate image restoration.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to prepare the system for resume from a hibernation
+ * image.
+ *
+ * If the restore fails after this function has been called,
+ * platform_restore_cleanup() must be called.
+ */
+static int platform_pre_restore(int platform_mode)
+{
+ return (platform_mode && hibernation_ops) ?
+ hibernation_ops->pre_restore() : 0;
+}
+
+/**
+ * platform_restore_cleanup - Switch to the working state after failing restore.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Use the platform driver to switch the system to the normal mode of operation
+ * after a failing restore.
+ *
+ * If platform_pre_restore() has been called before the failing restore, this
+ * function must be called too, regardless of the result of
+ * platform_pre_restore().
+ */
+static void platform_restore_cleanup(int platform_mode)
+{
+ if (platform_mode && hibernation_ops)
+ hibernation_ops->restore_cleanup();
+}
+
+/**
+ * platform_recover - Recover from a failure to suspend devices.
+ * @platform_mode: Whether or not to use the platform driver.
+ */
+static void platform_recover(int platform_mode)
+{
+ if (platform_mode && hibernation_ops && hibernation_ops->recover)
+ hibernation_ops->recover();
+}
+
+/**
+ * swsusp_show_speed - Print time elapsed between two events during hibernation.
+ * @start: Starting event.
+ * @stop: Final event.
+ * @nr_pages: Number of memory pages processed between @start and @stop.
+ * @msg: Additional diagnostic message to print.
+ */
+void swsusp_show_speed(ktime_t start, ktime_t stop,
+ unsigned nr_pages, char *msg)
+{
+ ktime_t diff;
+ u64 elapsed_centisecs64;
+ unsigned int centisecs;
+ unsigned int k;
+ unsigned int kps;
+
+ diff = ktime_sub(stop, start);
+ elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
+ centisecs = elapsed_centisecs64;
+ if (centisecs == 0)
+ centisecs = 1; /* avoid div-by-zero */
+ k = nr_pages * (PAGE_SIZE / 1024);
+ kps = (k * 100) / centisecs;
+ pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
+ msg, k, centisecs / 100, centisecs % 100, kps / 1000,
+ (kps % 1000) / 10);
+}
+
+/**
+ * create_image - Create a hibernation image.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Execute device drivers' "late" and "noirq" freeze callbacks, create a
+ * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
+ *
+ * Control reappears in this routine after the subsequent restore.
+ */
+static int create_image(int platform_mode)
+{
+ int error;
+
+ error = dpm_suspend_end(PMSG_FREEZE);
+ if (error) {
+ pr_err("Some devices failed to power down, aborting hibernation\n");
+ return error;
+ }
+
+ error = platform_pre_snapshot(platform_mode);
+ if (error || hibernation_test(TEST_PLATFORM))
+ goto Platform_finish;
+
+ error = disable_nonboot_cpus();
+ if (error || hibernation_test(TEST_CPUS))
+ goto Enable_cpus;
+
+ local_irq_disable();
+
+ system_state = SYSTEM_SUSPEND;
+
+ error = syscore_suspend();
+ if (error) {
+ pr_err("Some system devices failed to power down, aborting hibernation\n");
+ goto Enable_irqs;
+ }
+
+ if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
+ goto Power_up;
+
+ in_suspend = 1;
+ save_processor_state();
+ trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
+ error = swsusp_arch_suspend();
+ /* Restore control flow magically appears here */
+ restore_processor_state();
+ trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
+ if (error)
+ pr_err("Error %d creating hibernation image\n", error);
+
+ if (!in_suspend) {
+ events_check_enabled = false;
+ clear_free_pages();
+ }
+
+ platform_leave(platform_mode);
+
+ Power_up:
+ syscore_resume();
+
+ Enable_irqs:
+ system_state = SYSTEM_RUNNING;
+ local_irq_enable();
+
+ Enable_cpus:
+ enable_nonboot_cpus();
+
+ Platform_finish:
+ platform_finish(platform_mode);
+
+ dpm_resume_start(in_suspend ?
+ (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
+
+ return error;
+}
+
+/**
+ * hibernation_snapshot - Quiesce devices and create a hibernation image.
+ * @platform_mode: If set, use platform driver to prepare for the transition.
+ *
+ * This routine must be called with system_transition_mutex held.
+ */
+int hibernation_snapshot(int platform_mode)
+{
+ pm_message_t msg;
+ int error;
+
+ pm_suspend_clear_flags();
+ error = platform_begin(platform_mode);
+ if (error)
+ goto Close;
+
+ /* Preallocate image memory before shutting down devices. */
+ error = hibernate_preallocate_memory();
+ if (error)
+ goto Close;
+
+ error = freeze_kernel_threads();
+ if (error)
+ goto Cleanup;
+
+ if (hibernation_test(TEST_FREEZER)) {
+
+ /*
+ * Indicate to the caller that we are returning due to a
+ * successful freezer test.
+ */
+ freezer_test_done = true;
+ goto Thaw;
+ }
+
+ error = dpm_prepare(PMSG_FREEZE);
+ if (error) {
+ dpm_complete(PMSG_RECOVER);
+ goto Thaw;
+ }
+
+ suspend_console();
+ pm_restrict_gfp_mask();
+
+ error = dpm_suspend(PMSG_FREEZE);
+
+ if (error || hibernation_test(TEST_DEVICES))
+ platform_recover(platform_mode);
+ else
+ error = create_image(platform_mode);
+
+ /*
+ * In the case that we call create_image() above, the control
+ * returns here (1) after the image has been created or the
+ * image creation has failed and (2) after a successful restore.
+ */
+
+ /* We may need to release the preallocated image pages here. */
+ if (error || !in_suspend)
+ swsusp_free();
+
+ msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
+ dpm_resume(msg);
+
+ if (error || !in_suspend)
+ pm_restore_gfp_mask();
+
+ resume_console();
+ dpm_complete(msg);
+
+ Close:
+ platform_end(platform_mode);
+ return error;
+
+ Thaw:
+ thaw_kernel_threads();
+ Cleanup:
+ swsusp_free();
+ goto Close;
+}
+
+int __weak hibernate_resume_nonboot_cpu_disable(void)
+{
+ return disable_nonboot_cpus();
+}
+
+/**
+ * resume_target_kernel - Restore system state from a hibernation image.
+ * @platform_mode: Whether or not to use the platform driver.
+ *
+ * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
+ * contents of highmem that have not been restored yet from the image and run
+ * the low-level code that will restore the remaining contents of memory and
+ * switch to the just restored target kernel.
+ */
+static int resume_target_kernel(bool platform_mode)
+{
+ int error;
+
+ error = dpm_suspend_end(PMSG_QUIESCE);
+ if (error) {
+ pr_err("Some devices failed to power down, aborting resume\n");
+ return error;
+ }
+
+ error = platform_pre_restore(platform_mode);
+ if (error)
+ goto Cleanup;
+
+ error = hibernate_resume_nonboot_cpu_disable();
+ if (error)
+ goto Enable_cpus;
+
+ local_irq_disable();
+ system_state = SYSTEM_SUSPEND;
+
+ error = syscore_suspend();
+ if (error)
+ goto Enable_irqs;
+
+ save_processor_state();
+ error = restore_highmem();
+ if (!error) {
+ error = swsusp_arch_resume();
+ /*
+ * The code below is only ever reached in case of a failure.
+ * Otherwise, execution continues at the place where
+ * swsusp_arch_suspend() was called.
+ */
+ BUG_ON(!error);
+ /*
+ * This call to restore_highmem() reverts the changes made by
+ * the previous one.
+ */
+ restore_highmem();
+ }
+ /*
+ * The only reason why swsusp_arch_resume() can fail is memory being
+ * very tight, so we have to free it as soon as we can to avoid
+ * subsequent failures.
+ */
+ swsusp_free();
+ restore_processor_state();
+ touch_softlockup_watchdog();
+
+ syscore_resume();
+
+ Enable_irqs:
+ system_state = SYSTEM_RUNNING;
+ local_irq_enable();
+
+ Enable_cpus:
+ enable_nonboot_cpus();
+
+ Cleanup:
+ platform_restore_cleanup(platform_mode);
+
+ dpm_resume_start(PMSG_RECOVER);
+
+ return error;
+}
+
+/**
+ * hibernation_restore - Quiesce devices and restore from a hibernation image.
+ * @platform_mode: If set, use platform driver to prepare for the transition.
+ *
+ * This routine must be called with system_transition_mutex held. If it is
+ * successful, control reappears in the restored target kernel in
+ * hibernation_snapshot().
+ */
+int hibernation_restore(int platform_mode)
+{
+ int error;
+
+ pm_prepare_console();
+ suspend_console();
+ pm_restrict_gfp_mask();
+ error = dpm_suspend_start(PMSG_QUIESCE);
+ if (!error) {
+ error = resume_target_kernel(platform_mode);
+ /*
+ * The above should either succeed and jump to the new kernel,
+ * or return with an error. Otherwise things are just
+ * undefined, so let's be paranoid.
+ */
+ BUG_ON(!error);
+ }
+ dpm_resume_end(PMSG_RECOVER);
+ pm_restore_gfp_mask();
+ resume_console();
+ pm_restore_console();
+ return error;
+}
+
+/**
+ * hibernation_platform_enter - Power off the system using the platform driver.
+ */
+int hibernation_platform_enter(void)
+{
+ int error;
+
+ if (!hibernation_ops)
+ return -ENOSYS;
+
+ /*
+ * We have cancelled the power transition by running
+ * hibernation_ops->finish() before saving the image, so we should let
+ * the firmware know that we're going to enter the sleep state after all
+ */
+ error = hibernation_ops->begin();
+ if (error)
+ goto Close;
+
+ entering_platform_hibernation = true;
+ suspend_console();
+ error = dpm_suspend_start(PMSG_HIBERNATE);
+ if (error) {
+ if (hibernation_ops->recover)
+ hibernation_ops->recover();
+ goto Resume_devices;
+ }
+
+ error = dpm_suspend_end(PMSG_HIBERNATE);
+ if (error)
+ goto Resume_devices;
+
+ error = hibernation_ops->prepare();
+ if (error)
+ goto Platform_finish;
+
+ error = disable_nonboot_cpus();
+ if (error)
+ goto Enable_cpus;
+
+ local_irq_disable();
+ system_state = SYSTEM_SUSPEND;
+ syscore_suspend();
+ if (pm_wakeup_pending()) {
+ error = -EAGAIN;
+ goto Power_up;
+ }
+
+ hibernation_ops->enter();
+ /* We should never get here */
+ while (1);
+
+ Power_up:
+ syscore_resume();
+ system_state = SYSTEM_RUNNING;
+ local_irq_enable();
+
+ Enable_cpus:
+ enable_nonboot_cpus();
+
+ Platform_finish:
+ hibernation_ops->finish();
+
+ dpm_resume_start(PMSG_RESTORE);
+
+ Resume_devices:
+ entering_platform_hibernation = false;
+ dpm_resume_end(PMSG_RESTORE);
+ resume_console();
+
+ Close:
+ hibernation_ops->end();
+
+ return error;
+}
+
+/**
+ * power_down - Shut the machine down for hibernation.
+ *
+ * Use the platform driver, if configured, to put the system into the sleep
+ * state corresponding to hibernation, or try to power it off or reboot,
+ * depending on the value of hibernation_mode.
+ */
+static void power_down(void)
+{
+#ifdef CONFIG_SUSPEND
+ int error;
+
+ if (hibernation_mode == HIBERNATION_SUSPEND) {
+ error = suspend_devices_and_enter(PM_SUSPEND_MEM);
+ if (error) {
+ hibernation_mode = hibernation_ops ?
+ HIBERNATION_PLATFORM :
+ HIBERNATION_SHUTDOWN;
+ } else {
+ /* Restore swap signature. */
+ error = swsusp_unmark();
+ if (error)
+ pr_err("Swap will be unusable! Try swapon -a.\n");
+
+ return;
+ }
+ }
+#endif
+
+ switch (hibernation_mode) {
+ case HIBERNATION_REBOOT:
+ kernel_restart(NULL);
+ break;
+ case HIBERNATION_PLATFORM:
+ hibernation_platform_enter();
+ /* Fall through */
+ case HIBERNATION_SHUTDOWN:
+ if (pm_power_off)
+ kernel_power_off();
+ break;
+ }
+ kernel_halt();
+ /*
+ * Valid image is on the disk, if we continue we risk serious data
+ * corruption after resume.
+ */
+ pr_crit("Power down manually\n");
+ while (1)
+ cpu_relax();
+}
+
+static int load_image_and_restore(void)
+{
+ int error;
+ unsigned int flags;
+
+ pm_pr_dbg("Loading hibernation image.\n");
+
+ lock_device_hotplug();
+ error = create_basic_memory_bitmaps();
+ if (error)
+ goto Unlock;
+
+ error = swsusp_read(&flags);
+ swsusp_close(FMODE_READ);
+ if (!error)
+ hibernation_restore(flags & SF_PLATFORM_MODE);
+
+ pr_err("Failed to load hibernation image, recovering.\n");
+ swsusp_free();
+ free_basic_memory_bitmaps();
+ Unlock:
+ unlock_device_hotplug();
+
+ return error;
+}
+
+/**
+ * hibernate - Carry out system hibernation, including saving the image.
+ */
+int hibernate(void)
+{
+ int error, nr_calls = 0;
+ bool snapshot_test = false;
+
+ if (!hibernation_available()) {
+ pm_pr_dbg("Hibernation not available.\n");
+ return -EPERM;
+ }
+
+ lock_system_sleep();
+ /* The snapshot device should not be opened while we're running */
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ error = -EBUSY;
+ goto Unlock;
+ }
+
+ pr_info("hibernation entry\n");
+ pm_prepare_console();
+ error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
+ if (error) {
+ nr_calls--;
+ goto Exit;
+ }
+
+ pr_info("Syncing filesystems ... \n");
+ ksys_sync();
+ pr_info("done.\n");
+
+ error = freeze_processes();
+ if (error)
+ goto Exit;
+
+ lock_device_hotplug();
+ /* Allocate memory management structures */
+ error = create_basic_memory_bitmaps();
+ if (error)
+ goto Thaw;
+
+ error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
+ if (error || freezer_test_done)
+ goto Free_bitmaps;
+
+ if (in_suspend) {
+ unsigned int flags = 0;
+
+ if (hibernation_mode == HIBERNATION_PLATFORM)
+ flags |= SF_PLATFORM_MODE;
+ if (nocompress)
+ flags |= SF_NOCOMPRESS_MODE;
+ else
+ flags |= SF_CRC32_MODE;
+
+ pm_pr_dbg("Writing image.\n");
+ error = swsusp_write(flags);
+ swsusp_free();
+ if (!error) {
+ if (hibernation_mode == HIBERNATION_TEST_RESUME)
+ snapshot_test = true;
+ else
+ power_down();
+ }
+ in_suspend = 0;
+ pm_restore_gfp_mask();
+ } else {
+ pm_pr_dbg("Image restored successfully.\n");
+ }
+
+ Free_bitmaps:
+ free_basic_memory_bitmaps();
+ Thaw:
+ unlock_device_hotplug();
+ if (snapshot_test) {
+ pm_pr_dbg("Checking hibernation image\n");
+ error = swsusp_check();
+ if (!error)
+ error = load_image_and_restore();
+ }
+ thaw_processes();
+
+ /* Don't bother checking whether freezer_test_done is true */
+ freezer_test_done = false;
+ Exit:
+ __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
+ pm_restore_console();
+ atomic_inc(&snapshot_device_available);
+ Unlock:
+ unlock_system_sleep();
+ pr_info("hibernation exit\n");
+
+ return error;
+}
+
+
+/**
+ * software_resume - Resume from a saved hibernation image.
+ *
+ * This routine is called as a late initcall, when all devices have been
+ * discovered and initialized already.
+ *
+ * The image reading code is called to see if there is a hibernation image
+ * available for reading. If that is the case, devices are quiesced and the
+ * contents of memory is restored from the saved image.
+ *
+ * If this is successful, control reappears in the restored target kernel in
+ * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
+ * attempts to recover gracefully and make the kernel return to the normal mode
+ * of operation.
+ */
+static int software_resume(void)
+{
+ int error, nr_calls = 0;
+
+ /*
+ * If the user said "noresume".. bail out early.
+ */
+ if (noresume || !hibernation_available())
+ return 0;
+
+ /*
+ * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
+ * is configured into the kernel. Since the regular hibernate
+ * trigger path is via sysfs which takes a buffer mutex before
+ * calling hibernate functions (which take system_transition_mutex)
+ * this can cause lockdep to complain about a possible ABBA deadlock
+ * which cannot happen since we're in the boot code here and
+ * sysfs can't be invoked yet. Therefore, we use a subclass
+ * here to avoid lockdep complaining.
+ */
+ mutex_lock_nested(&system_transition_mutex, SINGLE_DEPTH_NESTING);
+
+ if (swsusp_resume_device)
+ goto Check_image;
+
+ if (!strlen(resume_file)) {
+ error = -ENOENT;
+ goto Unlock;
+ }
+
+ pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
+
+ if (resume_delay) {
+ pr_info("Waiting %dsec before reading resume device ...\n",
+ resume_delay);
+ ssleep(resume_delay);
+ }
+
+ /* Check if the device is there */
+ swsusp_resume_device = name_to_dev_t(resume_file);
+
+ /*
+ * name_to_dev_t is ineffective to verify parition if resume_file is in
+ * integer format. (e.g. major:minor)
+ */
+ if (isdigit(resume_file[0]) && resume_wait) {
+ int partno;
+ while (!get_gendisk(swsusp_resume_device, &partno))
+ msleep(10);
+ }
+
+ if (!swsusp_resume_device) {
+ /*
+ * Some device discovery might still be in progress; we need
+ * to wait for this to finish.
+ */
+ wait_for_device_probe();
+
+ if (resume_wait) {
+ while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
+ msleep(10);
+ async_synchronize_full();
+ }
+
+ swsusp_resume_device = name_to_dev_t(resume_file);
+ if (!swsusp_resume_device) {
+ error = -ENODEV;
+ goto Unlock;
+ }
+ }
+
+ Check_image:
+ pm_pr_dbg("Hibernation image partition %d:%d present\n",
+ MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
+
+ pm_pr_dbg("Looking for hibernation image.\n");
+ error = swsusp_check();
+ if (error)
+ goto Unlock;
+
+ /* The snapshot device should not be opened while we're running */
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ error = -EBUSY;
+ swsusp_close(FMODE_READ);
+ goto Unlock;
+ }
+
+ pr_info("resume from hibernation\n");
+ pm_prepare_console();
+ error = __pm_notifier_call_chain(PM_RESTORE_PREPARE, -1, &nr_calls);
+ if (error) {
+ nr_calls--;
+ goto Close_Finish;
+ }
+
+ pm_pr_dbg("Preparing processes for restore.\n");
+ error = freeze_processes();
+ if (error)
+ goto Close_Finish;
+ error = load_image_and_restore();
+ thaw_processes();
+ Finish:
+ __pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL);
+ pm_restore_console();
+ pr_info("resume from hibernation failed (%d)\n", error);
+ atomic_inc(&snapshot_device_available);
+ /* For success case, the suspend path will release the lock */
+ Unlock:
+ mutex_unlock(&system_transition_mutex);
+ pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
+ return error;
+ Close_Finish:
+ swsusp_close(FMODE_READ);
+ goto Finish;
+}
+
+late_initcall_sync(software_resume);
+
+
+static const char * const hibernation_modes[] = {
+ [HIBERNATION_PLATFORM] = "platform",
+ [HIBERNATION_SHUTDOWN] = "shutdown",
+ [HIBERNATION_REBOOT] = "reboot",
+#ifdef CONFIG_SUSPEND
+ [HIBERNATION_SUSPEND] = "suspend",
+#endif
+ [HIBERNATION_TEST_RESUME] = "test_resume",
+};
+
+/*
+ * /sys/power/disk - Control hibernation mode.
+ *
+ * Hibernation can be handled in several ways. There are a few different ways
+ * to put the system into the sleep state: using the platform driver (e.g. ACPI
+ * or other hibernation_ops), powering it off or rebooting it (for testing
+ * mostly).
+ *
+ * The sysfs file /sys/power/disk provides an interface for selecting the
+ * hibernation mode to use. Reading from this file causes the available modes
+ * to be printed. There are 3 modes that can be supported:
+ *
+ * 'platform'
+ * 'shutdown'
+ * 'reboot'
+ *
+ * If a platform hibernation driver is in use, 'platform' will be supported
+ * and will be used by default. Otherwise, 'shutdown' will be used by default.
+ * The selected option (i.e. the one corresponding to the current value of
+ * hibernation_mode) is enclosed by a square bracket.
+ *
+ * To select a given hibernation mode it is necessary to write the mode's
+ * string representation (as returned by reading from /sys/power/disk) back
+ * into /sys/power/disk.
+ */
+
+static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ int i;
+ char *start = buf;
+
+ if (!hibernation_available())
+ return sprintf(buf, "[disabled]\n");
+
+ for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
+ if (!hibernation_modes[i])
+ continue;
+ switch (i) {
+ case HIBERNATION_SHUTDOWN:
+ case HIBERNATION_REBOOT:
+#ifdef CONFIG_SUSPEND
+ case HIBERNATION_SUSPEND:
+#endif
+ case HIBERNATION_TEST_RESUME:
+ break;
+ case HIBERNATION_PLATFORM:
+ if (hibernation_ops)
+ break;
+ /* not a valid mode, continue with loop */
+ continue;
+ }
+ if (i == hibernation_mode)
+ buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
+ else
+ buf += sprintf(buf, "%s ", hibernation_modes[i]);
+ }
+ buf += sprintf(buf, "\n");
+ return buf-start;
+}
+
+static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ int error = 0;
+ int i;
+ int len;
+ char *p;
+ int mode = HIBERNATION_INVALID;
+
+ if (!hibernation_available())
+ return -EPERM;
+
+ p = memchr(buf, '\n', n);
+ len = p ? p - buf : n;
+
+ lock_system_sleep();
+ for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
+ if (len == strlen(hibernation_modes[i])
+ && !strncmp(buf, hibernation_modes[i], len)) {
+ mode = i;
+ break;
+ }
+ }
+ if (mode != HIBERNATION_INVALID) {
+ switch (mode) {
+ case HIBERNATION_SHUTDOWN:
+ case HIBERNATION_REBOOT:
+#ifdef CONFIG_SUSPEND
+ case HIBERNATION_SUSPEND:
+#endif
+ case HIBERNATION_TEST_RESUME:
+ hibernation_mode = mode;
+ break;
+ case HIBERNATION_PLATFORM:
+ if (hibernation_ops)
+ hibernation_mode = mode;
+ else
+ error = -EINVAL;
+ }
+ } else
+ error = -EINVAL;
+
+ if (!error)
+ pm_pr_dbg("Hibernation mode set to '%s'\n",
+ hibernation_modes[mode]);
+ unlock_system_sleep();
+ return error ? error : n;
+}
+
+power_attr(disk);
+
+static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
+ MINOR(swsusp_resume_device));
+}
+
+static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ dev_t res;
+ int len = n;
+ char *name;
+
+ if (len && buf[len-1] == '\n')
+ len--;
+ name = kstrndup(buf, len, GFP_KERNEL);
+ if (!name)
+ return -ENOMEM;
+
+ res = name_to_dev_t(name);
+ kfree(name);
+ if (!res)
+ return -EINVAL;
+
+ lock_system_sleep();
+ swsusp_resume_device = res;
+ unlock_system_sleep();
+ pm_pr_dbg("Configured resume from disk to %u\n", swsusp_resume_device);
+ noresume = 0;
+ software_resume();
+ return n;
+}
+
+power_attr(resume);
+
+static ssize_t resume_offset_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
+}
+
+static ssize_t resume_offset_store(struct kobject *kobj,
+ struct kobj_attribute *attr, const char *buf,
+ size_t n)
+{
+ unsigned long long offset;
+ int rc;
+
+ rc = kstrtoull(buf, 0, &offset);
+ if (rc)
+ return rc;
+ swsusp_resume_block = offset;
+
+ return n;
+}
+
+power_attr(resume_offset);
+
+static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%lu\n", image_size);
+}
+
+static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long size;
+
+ if (sscanf(buf, "%lu", &size) == 1) {
+ image_size = size;
+ return n;
+ }
+
+ return -EINVAL;
+}
+
+power_attr(image_size);
+
+static ssize_t reserved_size_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%lu\n", reserved_size);
+}
+
+static ssize_t reserved_size_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long size;
+
+ if (sscanf(buf, "%lu", &size) == 1) {
+ reserved_size = size;
+ return n;
+ }
+
+ return -EINVAL;
+}
+
+power_attr(reserved_size);
+
+static struct attribute * g[] = {
+ &disk_attr.attr,
+ &resume_offset_attr.attr,
+ &resume_attr.attr,
+ &image_size_attr.attr,
+ &reserved_size_attr.attr,
+ NULL,
+};
+
+
+static const struct attribute_group attr_group = {
+ .attrs = g,
+};
+
+
+static int __init pm_disk_init(void)
+{
+ return sysfs_create_group(power_kobj, &attr_group);
+}
+
+core_initcall(pm_disk_init);
+
+
+static int __init resume_setup(char *str)
+{
+ if (noresume)
+ return 1;
+
+ strncpy( resume_file, str, 255 );
+ return 1;
+}
+
+static int __init resume_offset_setup(char *str)
+{
+ unsigned long long offset;
+
+ if (noresume)
+ return 1;
+
+ if (sscanf(str, "%llu", &offset) == 1)
+ swsusp_resume_block = offset;
+
+ return 1;
+}
+
+static int __init hibernate_setup(char *str)
+{
+ if (!strncmp(str, "noresume", 8)) {
+ noresume = 1;
+ } else if (!strncmp(str, "nocompress", 10)) {
+ nocompress = 1;
+ } else if (!strncmp(str, "no", 2)) {
+ noresume = 1;
+ nohibernate = 1;
+ } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
+ && !strncmp(str, "protect_image", 13)) {
+ enable_restore_image_protection();
+ }
+ return 1;
+}
+
+static int __init noresume_setup(char *str)
+{
+ noresume = 1;
+ return 1;
+}
+
+static int __init resumewait_setup(char *str)
+{
+ resume_wait = 1;
+ return 1;
+}
+
+static int __init resumedelay_setup(char *str)
+{
+ int rc = kstrtouint(str, 0, &resume_delay);
+
+ if (rc)
+ return rc;
+ return 1;
+}
+
+static int __init nohibernate_setup(char *str)
+{
+ noresume = 1;
+ nohibernate = 1;
+ return 1;
+}
+
+__setup("noresume", noresume_setup);
+__setup("resume_offset=", resume_offset_setup);
+__setup("resume=", resume_setup);
+__setup("hibernate=", hibernate_setup);
+__setup("resumewait", resumewait_setup);
+__setup("resumedelay=", resumedelay_setup);
+__setup("nohibernate", nohibernate_setup);
diff --git a/kernel/power/main.c b/kernel/power/main.c
new file mode 100644
index 0000000..35b5082
--- /dev/null
+++ b/kernel/power/main.c
@@ -0,0 +1,824 @@
+/*
+ * kernel/power/main.c - PM subsystem core functionality.
+ *
+ * Copyright (c) 2003 Patrick Mochel
+ * Copyright (c) 2003 Open Source Development Lab
+ *
+ * This file is released under the GPLv2
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/kobject.h>
+#include <linux/string.h>
+#include <linux/pm-trace.h>
+#include <linux/workqueue.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/suspend.h>
+
+#include "power.h"
+
+#ifdef CONFIG_PM_SLEEP
+
+void lock_system_sleep(void)
+{
+ current->flags |= PF_FREEZER_SKIP;
+ mutex_lock(&system_transition_mutex);
+}
+EXPORT_SYMBOL_GPL(lock_system_sleep);
+
+void unlock_system_sleep(void)
+{
+ /*
+ * Don't use freezer_count() because we don't want the call to
+ * try_to_freeze() here.
+ *
+ * Reason:
+ * Fundamentally, we just don't need it, because freezing condition
+ * doesn't come into effect until we release the
+ * system_transition_mutex lock, since the freezer always works with
+ * system_transition_mutex held.
+ *
+ * More importantly, in the case of hibernation,
+ * unlock_system_sleep() gets called in snapshot_read() and
+ * snapshot_write() when the freezing condition is still in effect.
+ * Which means, if we use try_to_freeze() here, it would make them
+ * enter the refrigerator, thus causing hibernation to lockup.
+ */
+ current->flags &= ~PF_FREEZER_SKIP;
+ mutex_unlock(&system_transition_mutex);
+}
+EXPORT_SYMBOL_GPL(unlock_system_sleep);
+
+/* Routines for PM-transition notifications */
+
+static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
+
+int register_pm_notifier(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_register(&pm_chain_head, nb);
+}
+EXPORT_SYMBOL_GPL(register_pm_notifier);
+
+int unregister_pm_notifier(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_unregister(&pm_chain_head, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_pm_notifier);
+
+int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls)
+{
+ int ret;
+
+ ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL,
+ nr_to_call, nr_calls);
+
+ return notifier_to_errno(ret);
+}
+int pm_notifier_call_chain(unsigned long val)
+{
+ return __pm_notifier_call_chain(val, -1, NULL);
+}
+
+/* If set, devices may be suspended and resumed asynchronously. */
+int pm_async_enabled = 1;
+
+static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%d\n", pm_async_enabled);
+}
+
+static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long val;
+
+ if (kstrtoul(buf, 10, &val))
+ return -EINVAL;
+
+ if (val > 1)
+ return -EINVAL;
+
+ pm_async_enabled = val;
+ return n;
+}
+
+power_attr(pm_async);
+
+#ifdef CONFIG_SUSPEND
+static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ char *s = buf;
+ suspend_state_t i;
+
+ for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
+ if (mem_sleep_states[i]) {
+ const char *label = mem_sleep_states[i];
+
+ if (mem_sleep_current == i)
+ s += sprintf(s, "[%s] ", label);
+ else
+ s += sprintf(s, "%s ", label);
+ }
+
+ /* Convert the last space to a newline if needed. */
+ if (s != buf)
+ *(s-1) = '\n';
+
+ return (s - buf);
+}
+
+static suspend_state_t decode_suspend_state(const char *buf, size_t n)
+{
+ suspend_state_t state;
+ char *p;
+ int len;
+
+ p = memchr(buf, '\n', n);
+ len = p ? p - buf : n;
+
+ for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
+ const char *label = mem_sleep_states[state];
+
+ if (label && len == strlen(label) && !strncmp(buf, label, len))
+ return state;
+ }
+
+ return PM_SUSPEND_ON;
+}
+
+static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ suspend_state_t state;
+ int error;
+
+ error = pm_autosleep_lock();
+ if (error)
+ return error;
+
+ if (pm_autosleep_state() > PM_SUSPEND_ON) {
+ error = -EBUSY;
+ goto out;
+ }
+
+ state = decode_suspend_state(buf, n);
+ if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
+ mem_sleep_current = state;
+ else
+ error = -EINVAL;
+
+ out:
+ pm_autosleep_unlock();
+ return error ? error : n;
+}
+
+power_attr(mem_sleep);
+#endif /* CONFIG_SUSPEND */
+
+#ifdef CONFIG_PM_SLEEP_DEBUG
+int pm_test_level = TEST_NONE;
+
+static const char * const pm_tests[__TEST_AFTER_LAST] = {
+ [TEST_NONE] = "none",
+ [TEST_CORE] = "core",
+ [TEST_CPUS] = "processors",
+ [TEST_PLATFORM] = "platform",
+ [TEST_DEVICES] = "devices",
+ [TEST_FREEZER] = "freezer",
+};
+
+static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ char *s = buf;
+ int level;
+
+ for (level = TEST_FIRST; level <= TEST_MAX; level++)
+ if (pm_tests[level]) {
+ if (level == pm_test_level)
+ s += sprintf(s, "[%s] ", pm_tests[level]);
+ else
+ s += sprintf(s, "%s ", pm_tests[level]);
+ }
+
+ if (s != buf)
+ /* convert the last space to a newline */
+ *(s-1) = '\n';
+
+ return (s - buf);
+}
+
+static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ const char * const *s;
+ int level;
+ char *p;
+ int len;
+ int error = -EINVAL;
+
+ p = memchr(buf, '\n', n);
+ len = p ? p - buf : n;
+
+ lock_system_sleep();
+
+ level = TEST_FIRST;
+ for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
+ if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
+ pm_test_level = level;
+ error = 0;
+ break;
+ }
+
+ unlock_system_sleep();
+
+ return error ? error : n;
+}
+
+power_attr(pm_test);
+#endif /* CONFIG_PM_SLEEP_DEBUG */
+
+#ifdef CONFIG_DEBUG_FS
+static char *suspend_step_name(enum suspend_stat_step step)
+{
+ switch (step) {
+ case SUSPEND_FREEZE:
+ return "freeze";
+ case SUSPEND_PREPARE:
+ return "prepare";
+ case SUSPEND_SUSPEND:
+ return "suspend";
+ case SUSPEND_SUSPEND_NOIRQ:
+ return "suspend_noirq";
+ case SUSPEND_RESUME_NOIRQ:
+ return "resume_noirq";
+ case SUSPEND_RESUME:
+ return "resume";
+ default:
+ return "";
+ }
+}
+
+static int suspend_stats_show(struct seq_file *s, void *unused)
+{
+ int i, index, last_dev, last_errno, last_step;
+
+ last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
+ last_dev %= REC_FAILED_NUM;
+ last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
+ last_errno %= REC_FAILED_NUM;
+ last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
+ last_step %= REC_FAILED_NUM;
+ seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
+ "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
+ "success", suspend_stats.success,
+ "fail", suspend_stats.fail,
+ "failed_freeze", suspend_stats.failed_freeze,
+ "failed_prepare", suspend_stats.failed_prepare,
+ "failed_suspend", suspend_stats.failed_suspend,
+ "failed_suspend_late",
+ suspend_stats.failed_suspend_late,
+ "failed_suspend_noirq",
+ suspend_stats.failed_suspend_noirq,
+ "failed_resume", suspend_stats.failed_resume,
+ "failed_resume_early",
+ suspend_stats.failed_resume_early,
+ "failed_resume_noirq",
+ suspend_stats.failed_resume_noirq);
+ seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
+ suspend_stats.failed_devs[last_dev]);
+ for (i = 1; i < REC_FAILED_NUM; i++) {
+ index = last_dev + REC_FAILED_NUM - i;
+ index %= REC_FAILED_NUM;
+ seq_printf(s, "\t\t\t%-s\n",
+ suspend_stats.failed_devs[index]);
+ }
+ seq_printf(s, " last_failed_errno:\t%-d\n",
+ suspend_stats.errno[last_errno]);
+ for (i = 1; i < REC_FAILED_NUM; i++) {
+ index = last_errno + REC_FAILED_NUM - i;
+ index %= REC_FAILED_NUM;
+ seq_printf(s, "\t\t\t%-d\n",
+ suspend_stats.errno[index]);
+ }
+ seq_printf(s, " last_failed_step:\t%-s\n",
+ suspend_step_name(
+ suspend_stats.failed_steps[last_step]));
+ for (i = 1; i < REC_FAILED_NUM; i++) {
+ index = last_step + REC_FAILED_NUM - i;
+ index %= REC_FAILED_NUM;
+ seq_printf(s, "\t\t\t%-s\n",
+ suspend_step_name(
+ suspend_stats.failed_steps[index]));
+ }
+
+ return 0;
+}
+
+static int suspend_stats_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, suspend_stats_show, NULL);
+}
+
+static const struct file_operations suspend_stats_operations = {
+ .open = suspend_stats_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init pm_debugfs_init(void)
+{
+ debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
+ NULL, NULL, &suspend_stats_operations);
+ return 0;
+}
+
+late_initcall(pm_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */
+
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM_SLEEP_DEBUG
+/*
+ * pm_print_times: print time taken by devices to suspend and resume.
+ *
+ * show() returns whether printing of suspend and resume times is enabled.
+ * store() accepts 0 or 1. 0 disables printing and 1 enables it.
+ */
+bool pm_print_times_enabled;
+
+static ssize_t pm_print_times_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", pm_print_times_enabled);
+}
+
+static ssize_t pm_print_times_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long val;
+
+ if (kstrtoul(buf, 10, &val))
+ return -EINVAL;
+
+ if (val > 1)
+ return -EINVAL;
+
+ pm_print_times_enabled = !!val;
+ return n;
+}
+
+power_attr(pm_print_times);
+
+static inline void pm_print_times_init(void)
+{
+ pm_print_times_enabled = !!initcall_debug;
+}
+
+static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA;
+}
+
+power_attr_ro(pm_wakeup_irq);
+
+bool pm_debug_messages_on __read_mostly;
+
+static ssize_t pm_debug_messages_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", pm_debug_messages_on);
+}
+
+static ssize_t pm_debug_messages_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long val;
+
+ if (kstrtoul(buf, 10, &val))
+ return -EINVAL;
+
+ if (val > 1)
+ return -EINVAL;
+
+ pm_debug_messages_on = !!val;
+ return n;
+}
+
+power_attr(pm_debug_messages);
+
+/**
+ * __pm_pr_dbg - Print a suspend debug message to the kernel log.
+ * @defer: Whether or not to use printk_deferred() to print the message.
+ * @fmt: Message format.
+ *
+ * The message will be emitted if enabled through the pm_debug_messages
+ * sysfs attribute.
+ */
+void __pm_pr_dbg(bool defer, const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+
+ if (!pm_debug_messages_on)
+ return;
+
+ va_start(args, fmt);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ if (defer)
+ printk_deferred(KERN_DEBUG "PM: %pV", &vaf);
+ else
+ printk(KERN_DEBUG "PM: %pV", &vaf);
+
+ va_end(args);
+}
+
+#else /* !CONFIG_PM_SLEEP_DEBUG */
+static inline void pm_print_times_init(void) {}
+#endif /* CONFIG_PM_SLEEP_DEBUG */
+
+struct kobject *power_kobj;
+
+/**
+ * state - control system sleep states.
+ *
+ * show() returns available sleep state labels, which may be "mem", "standby",
+ * "freeze" and "disk" (hibernation).
+ * See Documentation/admin-guide/pm/sleep-states.rst for a description of
+ * what they mean.
+ *
+ * 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)
+{
+ char *s = buf;
+#ifdef CONFIG_SUSPEND
+ suspend_state_t i;
+
+ for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
+ if (pm_states[i])
+ s += sprintf(s,"%s ", pm_states[i]);
+
+#endif
+ if (hibernation_available())
+ s += sprintf(s, "disk ");
+ if (s != buf)
+ /* convert the last space to a newline */
+ *(s-1) = '\n';
+ return (s - buf);
+}
+
+static suspend_state_t decode_state(const char *buf, size_t n)
+{
+#ifdef CONFIG_SUSPEND
+ suspend_state_t state;
+#endif
+ char *p;
+ int len;
+
+ p = memchr(buf, '\n', n);
+ len = p ? p - buf : n;
+
+ /* Check hibernation first. */
+ if (len == 4 && !strncmp(buf, "disk", len))
+ return PM_SUSPEND_MAX;
+
+#ifdef CONFIG_SUSPEND
+ for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
+ const char *label = pm_states[state];
+
+ if (label && len == strlen(label) && !strncmp(buf, label, len))
+ return state;
+ }
+#endif
+
+ return PM_SUSPEND_ON;
+}
+
+static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ suspend_state_t state;
+ int error;
+
+ error = pm_autosleep_lock();
+ if (error)
+ return error;
+
+ if (pm_autosleep_state() > PM_SUSPEND_ON) {
+ error = -EBUSY;
+ goto out;
+ }
+
+ state = decode_state(buf, n);
+ if (state < PM_SUSPEND_MAX) {
+ if (state == PM_SUSPEND_MEM)
+ state = mem_sleep_current;
+
+ error = pm_suspend(state);
+ } else if (state == PM_SUSPEND_MAX) {
+ error = hibernate();
+ } else {
+ error = -EINVAL;
+ }
+
+ out:
+ pm_autosleep_unlock();
+ return error ? error : n;
+}
+
+power_attr(state);
+
+#ifdef CONFIG_PM_SLEEP
+/*
+ * The 'wakeup_count' attribute, along with the functions defined in
+ * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
+ * handled in a non-racy way.
+ *
+ * If a wakeup event occurs when the system is in a sleep state, it simply is
+ * woken up. In turn, if an event that would wake the system up from a sleep
+ * state occurs when it is undergoing a transition to that sleep state, the
+ * transition should be aborted. Moreover, if such an event occurs when the
+ * system is in the working state, an attempt to start a transition to the
+ * given sleep state should fail during certain period after the detection of
+ * the event. Using the 'state' attribute alone is not sufficient to satisfy
+ * these requirements, because a wakeup event may occur exactly when 'state'
+ * is being written to and may be delivered to user space right before it is
+ * frozen, so the event will remain only partially processed until the system is
+ * woken up by another event. In particular, it won't cause the transition to
+ * a sleep state to be aborted.
+ *
+ * This difficulty may be overcome if user space uses 'wakeup_count' before
+ * writing to 'state'. It first should read from 'wakeup_count' and store
+ * the read value. Then, after carrying out its own preparations for the system
+ * transition to a sleep state, it should write the stored value to
+ * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
+ * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
+ * is allowed to write to 'state', but the transition will be aborted if there
+ * are any wakeup events detected after 'wakeup_count' was written to.
+ */
+
+static ssize_t wakeup_count_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ unsigned int val;
+
+ return pm_get_wakeup_count(&val, true) ?
+ sprintf(buf, "%u\n", val) : -EINTR;
+}
+
+static ssize_t wakeup_count_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned int val;
+ int error;
+
+ error = pm_autosleep_lock();
+ if (error)
+ return error;
+
+ if (pm_autosleep_state() > PM_SUSPEND_ON) {
+ error = -EBUSY;
+ goto out;
+ }
+
+ error = -EINVAL;
+ if (sscanf(buf, "%u", &val) == 1) {
+ if (pm_save_wakeup_count(val))
+ error = n;
+ else
+ pm_print_active_wakeup_sources();
+ }
+
+ out:
+ pm_autosleep_unlock();
+ return error;
+}
+
+power_attr(wakeup_count);
+
+#ifdef CONFIG_PM_AUTOSLEEP
+static ssize_t autosleep_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ suspend_state_t state = pm_autosleep_state();
+
+ if (state == PM_SUSPEND_ON)
+ return sprintf(buf, "off\n");
+
+#ifdef CONFIG_SUSPEND
+ if (state < PM_SUSPEND_MAX)
+ return sprintf(buf, "%s\n", pm_states[state] ?
+ pm_states[state] : "error");
+#endif
+#ifdef CONFIG_HIBERNATION
+ return sprintf(buf, "disk\n");
+#else
+ return sprintf(buf, "error");
+#endif
+}
+
+static ssize_t autosleep_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ suspend_state_t state = decode_state(buf, n);
+ int error;
+
+ if (state == PM_SUSPEND_ON
+ && strcmp(buf, "off") && strcmp(buf, "off\n"))
+ return -EINVAL;
+
+ if (state == PM_SUSPEND_MEM)
+ state = mem_sleep_current;
+
+ error = pm_autosleep_set_state(state);
+ return error ? error : n;
+}
+
+power_attr(autosleep);
+#endif /* CONFIG_PM_AUTOSLEEP */
+
+#ifdef CONFIG_PM_WAKELOCKS
+static ssize_t wake_lock_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return pm_show_wakelocks(buf, true);
+}
+
+static ssize_t wake_lock_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ int error = pm_wake_lock(buf);
+ return error ? error : n;
+}
+
+power_attr(wake_lock);
+
+static ssize_t wake_unlock_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return pm_show_wakelocks(buf, false);
+}
+
+static ssize_t wake_unlock_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ int error = pm_wake_unlock(buf);
+ return error ? error : n;
+}
+
+power_attr(wake_unlock);
+
+#endif /* CONFIG_PM_WAKELOCKS */
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM_TRACE
+int pm_trace_enabled;
+
+static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%d\n", pm_trace_enabled);
+}
+
+static ssize_t
+pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ int val;
+
+ if (sscanf(buf, "%d", &val) == 1) {
+ pm_trace_enabled = !!val;
+ if (pm_trace_enabled) {
+ pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
+ "PM: Correct system time has to be restored manually after resume.\n");
+ }
+ return n;
+ }
+ return -EINVAL;
+}
+
+power_attr(pm_trace);
+
+static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return show_trace_dev_match(buf, PAGE_SIZE);
+}
+
+power_attr_ro(pm_trace_dev_match);
+
+#endif /* CONFIG_PM_TRACE */
+
+#ifdef CONFIG_FREEZER
+static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%u\n", freeze_timeout_msecs);
+}
+
+static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long val;
+
+ if (kstrtoul(buf, 10, &val))
+ return -EINVAL;
+
+ freeze_timeout_msecs = val;
+ return n;
+}
+
+power_attr(pm_freeze_timeout);
+
+#endif /* CONFIG_FREEZER*/
+
+static struct attribute * g[] = {
+ &state_attr.attr,
+#ifdef CONFIG_PM_TRACE
+ &pm_trace_attr.attr,
+ &pm_trace_dev_match_attr.attr,
+#endif
+#ifdef CONFIG_PM_SLEEP
+ &pm_async_attr.attr,
+ &wakeup_count_attr.attr,
+#ifdef CONFIG_SUSPEND
+ &mem_sleep_attr.attr,
+#endif
+#ifdef CONFIG_PM_AUTOSLEEP
+ &autosleep_attr.attr,
+#endif
+#ifdef CONFIG_PM_WAKELOCKS
+ &wake_lock_attr.attr,
+ &wake_unlock_attr.attr,
+#endif
+#ifdef CONFIG_PM_SLEEP_DEBUG
+ &pm_test_attr.attr,
+ &pm_print_times_attr.attr,
+ &pm_wakeup_irq_attr.attr,
+ &pm_debug_messages_attr.attr,
+#endif
+#endif
+#ifdef CONFIG_FREEZER
+ &pm_freeze_timeout_attr.attr,
+#endif
+ NULL,
+};
+
+static const struct attribute_group attr_group = {
+ .attrs = g,
+};
+
+struct workqueue_struct *pm_wq;
+EXPORT_SYMBOL_GPL(pm_wq);
+
+static int __init pm_start_workqueue(void)
+{
+ pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
+
+ return pm_wq ? 0 : -ENOMEM;
+}
+
+static int __init pm_init(void)
+{
+ int error = pm_start_workqueue();
+ if (error)
+ return error;
+ hibernate_image_size_init();
+ hibernate_reserved_size_init();
+ pm_states_init();
+ power_kobj = kobject_create_and_add("power", NULL);
+ if (!power_kobj)
+ return -ENOMEM;
+ error = sysfs_create_group(power_kobj, &attr_group);
+ if (error)
+ return error;
+ pm_print_times_init();
+ return pm_autosleep_init();
+}
+
+core_initcall(pm_init);
diff --git a/kernel/power/power.h b/kernel/power/power.h
new file mode 100644
index 0000000..9e58bdc
--- /dev/null
+++ b/kernel/power/power.h
@@ -0,0 +1,315 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/suspend.h>
+#include <linux/suspend_ioctls.h>
+#include <linux/utsname.h>
+#include <linux/freezer.h>
+#include <linux/compiler.h>
+
+struct swsusp_info {
+ struct new_utsname uts;
+ u32 version_code;
+ unsigned long num_physpages;
+ int cpus;
+ unsigned long image_pages;
+ unsigned long pages;
+ unsigned long size;
+} __aligned(PAGE_SIZE);
+
+#ifdef CONFIG_HIBERNATION
+/* kernel/power/snapshot.c */
+extern void __init hibernate_reserved_size_init(void);
+extern void __init hibernate_image_size_init(void);
+
+#ifdef CONFIG_ARCH_HIBERNATION_HEADER
+/* Maximum size of architecture specific data in a hibernation header */
+#define MAX_ARCH_HEADER_SIZE (sizeof(struct new_utsname) + 4)
+
+extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
+extern int arch_hibernation_header_restore(void *addr);
+
+static inline int init_header_complete(struct swsusp_info *info)
+{
+ return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
+}
+
+static inline char *check_image_kernel(struct swsusp_info *info)
+{
+ return arch_hibernation_header_restore(info) ?
+ "architecture specific data" : NULL;
+}
+#endif /* CONFIG_ARCH_HIBERNATION_HEADER */
+
+extern int hibernate_resume_nonboot_cpu_disable(void);
+
+/*
+ * Keep some memory free so that I/O operations can succeed without paging
+ * [Might this be more than 4 MB?]
+ */
+#define PAGES_FOR_IO ((4096 * 1024) >> PAGE_SHIFT)
+
+/*
+ * Keep 1 MB of memory free so that device drivers can allocate some pages in
+ * their .suspend() routines without breaking the suspend to disk.
+ */
+#define SPARE_PAGES ((1024 * 1024) >> PAGE_SHIFT)
+
+asmlinkage int swsusp_save(void);
+
+/* kernel/power/hibernate.c */
+extern bool freezer_test_done;
+
+extern int hibernation_snapshot(int platform_mode);
+extern int hibernation_restore(int platform_mode);
+extern int hibernation_platform_enter(void);
+
+#ifdef CONFIG_STRICT_KERNEL_RWX
+/* kernel/power/snapshot.c */
+extern void enable_restore_image_protection(void);
+#else
+static inline void enable_restore_image_protection(void) {}
+#endif /* CONFIG_STRICT_KERNEL_RWX */
+
+#else /* !CONFIG_HIBERNATION */
+
+static inline void hibernate_reserved_size_init(void) {}
+static inline void hibernate_image_size_init(void) {}
+#endif /* !CONFIG_HIBERNATION */
+
+extern int pfn_is_nosave(unsigned long);
+
+#define power_attr(_name) \
+static struct kobj_attribute _name##_attr = { \
+ .attr = { \
+ .name = __stringify(_name), \
+ .mode = 0644, \
+ }, \
+ .show = _name##_show, \
+ .store = _name##_store, \
+}
+
+#define power_attr_ro(_name) \
+static struct kobj_attribute _name##_attr = { \
+ .attr = { \
+ .name = __stringify(_name), \
+ .mode = S_IRUGO, \
+ }, \
+ .show = _name##_show, \
+}
+
+/* Preferred image size in bytes (default 500 MB) */
+extern unsigned long image_size;
+/* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
+extern unsigned long reserved_size;
+extern int in_suspend;
+extern dev_t swsusp_resume_device;
+extern sector_t swsusp_resume_block;
+
+extern int create_basic_memory_bitmaps(void);
+extern void free_basic_memory_bitmaps(void);
+extern int hibernate_preallocate_memory(void);
+
+extern void clear_free_pages(void);
+
+/**
+ * Auxiliary structure used for reading the snapshot image data and
+ * metadata from and writing them to the list of page backup entries
+ * (PBEs) which is the main data structure of swsusp.
+ *
+ * Using struct snapshot_handle we can transfer the image, including its
+ * metadata, as a continuous sequence of bytes with the help of
+ * snapshot_read_next() and snapshot_write_next().
+ *
+ * The code that writes the image to a storage or transfers it to
+ * the user land is required to use snapshot_read_next() for this
+ * purpose and it should not make any assumptions regarding the internal
+ * structure of the image. Similarly, the code that reads the image from
+ * a storage or transfers it from the user land is required to use
+ * snapshot_write_next().
+ *
+ * This may allow us to change the internal structure of the image
+ * in the future with considerably less effort.
+ */
+
+struct snapshot_handle {
+ unsigned int cur; /* number of the block of PAGE_SIZE bytes the
+ * next operation will refer to (ie. current)
+ */
+ void *buffer; /* address of the block to read from
+ * or write to
+ */
+ int sync_read; /* Set to one to notify the caller of
+ * snapshot_write_next() that it may
+ * need to call wait_on_bio_chain()
+ */
+};
+
+/* This macro returns the address from/to which the caller of
+ * snapshot_read_next()/snapshot_write_next() is allowed to
+ * read/write data after the function returns
+ */
+#define data_of(handle) ((handle).buffer)
+
+extern unsigned int snapshot_additional_pages(struct zone *zone);
+extern unsigned long snapshot_get_image_size(void);
+extern int snapshot_read_next(struct snapshot_handle *handle);
+extern int snapshot_write_next(struct snapshot_handle *handle);
+extern void snapshot_write_finalize(struct snapshot_handle *handle);
+extern int snapshot_image_loaded(struct snapshot_handle *handle);
+
+/* If unset, the snapshot device cannot be open. */
+extern atomic_t snapshot_device_available;
+
+extern sector_t alloc_swapdev_block(int swap);
+extern void free_all_swap_pages(int swap);
+extern int swsusp_swap_in_use(void);
+
+/*
+ * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
+ * the image header.
+ */
+#define SF_PLATFORM_MODE 1
+#define SF_NOCOMPRESS_MODE 2
+#define SF_CRC32_MODE 4
+
+/* kernel/power/hibernate.c */
+extern int swsusp_check(void);
+extern void swsusp_free(void);
+extern int swsusp_read(unsigned int *flags_p);
+extern int swsusp_write(unsigned int flags);
+extern void swsusp_close(fmode_t);
+#ifdef CONFIG_SUSPEND
+extern int swsusp_unmark(void);
+#endif
+
+struct timeval;
+/* kernel/power/swsusp.c */
+extern void swsusp_show_speed(ktime_t, ktime_t, unsigned int, char *);
+
+#ifdef CONFIG_SUSPEND
+/* kernel/power/suspend.c */
+extern const char * const pm_labels[];
+extern const char *pm_states[];
+extern const char *mem_sleep_states[];
+
+extern int suspend_devices_and_enter(suspend_state_t state);
+#else /* !CONFIG_SUSPEND */
+#define mem_sleep_current PM_SUSPEND_ON
+
+static inline int suspend_devices_and_enter(suspend_state_t state)
+{
+ return -ENOSYS;
+}
+#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, int nr_to_call,
+ int *nr_calls);
+extern int pm_notifier_call_chain(unsigned long val);
+#endif
+
+#ifdef CONFIG_HIGHMEM
+int restore_highmem(void);
+#else
+static inline unsigned int count_highmem_pages(void) { return 0; }
+static inline int restore_highmem(void) { return 0; }
+#endif
+
+/*
+ * Suspend test levels
+ */
+enum {
+ /* keep first */
+ TEST_NONE,
+ TEST_CORE,
+ TEST_CPUS,
+ TEST_PLATFORM,
+ TEST_DEVICES,
+ TEST_FREEZER,
+ /* keep last */
+ __TEST_AFTER_LAST
+};
+
+#define TEST_FIRST TEST_NONE
+#define TEST_MAX (__TEST_AFTER_LAST - 1)
+
+#ifdef CONFIG_PM_SLEEP_DEBUG
+extern int pm_test_level;
+#else
+#define pm_test_level (TEST_NONE)
+#endif
+
+#ifdef CONFIG_SUSPEND_FREEZER
+static inline int suspend_freeze_processes(void)
+{
+ int error;
+
+ error = freeze_processes();
+ /*
+ * freeze_processes() automatically thaws every task if freezing
+ * fails. So we need not do anything extra upon error.
+ */
+ if (error)
+ return error;
+
+ error = freeze_kernel_threads();
+ /*
+ * freeze_kernel_threads() thaws only kernel threads upon freezing
+ * failure. So we have to thaw the userspace tasks ourselves.
+ */
+ if (error)
+ thaw_processes();
+
+ return error;
+}
+
+static inline void suspend_thaw_processes(void)
+{
+ thaw_processes();
+}
+#else
+static inline int suspend_freeze_processes(void)
+{
+ return 0;
+}
+
+static inline void suspend_thaw_processes(void)
+{
+}
+#endif
+
+#ifdef CONFIG_PM_AUTOSLEEP
+
+/* kernel/power/autosleep.c */
+extern int pm_autosleep_init(void);
+extern int pm_autosleep_lock(void);
+extern void pm_autosleep_unlock(void);
+extern suspend_state_t pm_autosleep_state(void);
+extern int pm_autosleep_set_state(suspend_state_t state);
+
+#else /* !CONFIG_PM_AUTOSLEEP */
+
+static inline int pm_autosleep_init(void) { return 0; }
+static inline int pm_autosleep_lock(void) { return 0; }
+static inline void pm_autosleep_unlock(void) {}
+static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
+
+#endif /* !CONFIG_PM_AUTOSLEEP */
+
+#ifdef CONFIG_PM_WAKELOCKS
+
+/* kernel/power/wakelock.c */
+extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
+extern int pm_wake_lock(const char *buf);
+extern int pm_wake_unlock(const char *buf);
+
+#endif /* !CONFIG_PM_WAKELOCKS */
diff --git a/kernel/power/poweroff.c b/kernel/power/poweroff.c
new file mode 100644
index 0000000..7ef6866
--- /dev/null
+++ b/kernel/power/poweroff.c
@@ -0,0 +1,46 @@
+/*
+ * poweroff.c - sysrq handler to gracefully power down machine.
+ *
+ * This file is released under the GPL v2
+ */
+
+#include <linux/kernel.h>
+#include <linux/sysrq.h>
+#include <linux/init.h>
+#include <linux/pm.h>
+#include <linux/workqueue.h>
+#include <linux/reboot.h>
+#include <linux/cpumask.h>
+
+/*
+ * When the user hits Sys-Rq o to power down the machine this is the
+ * callback we use.
+ */
+
+static void do_poweroff(struct work_struct *dummy)
+{
+ kernel_power_off();
+}
+
+static DECLARE_WORK(poweroff_work, do_poweroff);
+
+static void handle_poweroff(int key)
+{
+ /* run sysrq poweroff on boot cpu */
+ schedule_work_on(cpumask_first(cpu_online_mask), &poweroff_work);
+}
+
+static struct sysrq_key_op sysrq_poweroff_op = {
+ .handler = handle_poweroff,
+ .help_msg = "poweroff(o)",
+ .action_msg = "Power Off",
+ .enable_mask = SYSRQ_ENABLE_BOOT,
+};
+
+static int __init pm_sysrq_init(void)
+{
+ register_sysrq_key('o', &sysrq_poweroff_op);
+ return 0;
+}
+
+subsys_initcall(pm_sysrq_init);
diff --git a/kernel/power/process.c b/kernel/power/process.c
new file mode 100644
index 0000000..7381d49
--- /dev/null
+++ b/kernel/power/process.c
@@ -0,0 +1,245 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * drivers/power/process.c - Functions for starting/stopping processes on
+ * suspend transitions.
+ *
+ * Originally from swsusp.
+ */
+
+
+#undef DEBUG
+
+#include <linux/interrupt.h>
+#include <linux/oom.h>
+#include <linux/suspend.h>
+#include <linux/module.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task.h>
+#include <linux/syscalls.h>
+#include <linux/freezer.h>
+#include <linux/delay.h>
+#include <linux/workqueue.h>
+#include <linux/kmod.h>
+#include <trace/events/power.h>
+#include <linux/cpuset.h>
+
+/*
+ * Timeout for stopping processes
+ */
+unsigned int __read_mostly freeze_timeout_msecs = 20 * MSEC_PER_SEC;
+
+static int try_to_freeze_tasks(bool user_only)
+{
+ struct task_struct *g, *p;
+ unsigned long end_time;
+ unsigned int todo;
+ bool wq_busy = false;
+ ktime_t start, end, elapsed;
+ unsigned int elapsed_msecs;
+ bool wakeup = false;
+ int sleep_usecs = USEC_PER_MSEC;
+
+ start = ktime_get_boottime();
+
+ end_time = jiffies + msecs_to_jiffies(freeze_timeout_msecs);
+
+ if (!user_only)
+ freeze_workqueues_begin();
+
+ while (true) {
+ todo = 0;
+ read_lock(&tasklist_lock);
+ for_each_process_thread(g, p) {
+ if (p == current || !freeze_task(p))
+ continue;
+
+ if (!freezer_should_skip(p))
+ todo++;
+ }
+ read_unlock(&tasklist_lock);
+
+ if (!user_only) {
+ wq_busy = freeze_workqueues_busy();
+ todo += wq_busy;
+ }
+
+ if (!todo || time_after(jiffies, end_time))
+ break;
+
+ if (pm_wakeup_pending()) {
+ wakeup = true;
+ break;
+ }
+
+ /*
+ * We need to retry, but first give the freezing tasks some
+ * time to enter the refrigerator. Start with an initial
+ * 1 ms sleep followed by exponential backoff until 8 ms.
+ */
+ usleep_range(sleep_usecs / 2, sleep_usecs);
+ if (sleep_usecs < 8 * USEC_PER_MSEC)
+ sleep_usecs *= 2;
+ }
+
+ end = ktime_get_boottime();
+ elapsed = ktime_sub(end, start);
+ elapsed_msecs = ktime_to_ms(elapsed);
+
+ if (todo) {
+ pr_cont("\n");
+ pr_err("Freezing of tasks %s after %d.%03d seconds "
+ "(%d tasks refusing to freeze, wq_busy=%d):\n",
+ wakeup ? "aborted" : "failed",
+ elapsed_msecs / 1000, elapsed_msecs % 1000,
+ todo - wq_busy, wq_busy);
+
+ if (wq_busy)
+ show_workqueue_state();
+
+ if (!wakeup) {
+ read_lock(&tasklist_lock);
+ for_each_process_thread(g, p) {
+ if (p != current && !freezer_should_skip(p)
+ && freezing(p) && !frozen(p))
+ sched_show_task(p);
+ }
+ read_unlock(&tasklist_lock);
+ }
+ } else {
+ pr_cont("(elapsed %d.%03d seconds) ", elapsed_msecs / 1000,
+ elapsed_msecs % 1000);
+ }
+
+ return todo ? -EBUSY : 0;
+}
+
+/**
+ * freeze_processes - Signal user space processes to enter the refrigerator.
+ * The current thread will not be frozen. The same process that calls
+ * freeze_processes must later call thaw_processes.
+ *
+ * On success, returns 0. On failure, -errno and system is fully thawed.
+ */
+int freeze_processes(void)
+{
+ int error;
+
+ error = __usermodehelper_disable(UMH_FREEZING);
+ if (error)
+ return error;
+
+ /* Make sure this task doesn't get frozen */
+ current->flags |= PF_SUSPEND_TASK;
+
+ if (!pm_freezing)
+ atomic_inc(&system_freezing_cnt);
+
+ pm_wakeup_clear(true);
+ pr_info("Freezing user space processes ... ");
+ pm_freezing = true;
+ error = try_to_freeze_tasks(true);
+ if (!error) {
+ __usermodehelper_set_disable_depth(UMH_DISABLED);
+ pr_cont("done.");
+ }
+ pr_cont("\n");
+ BUG_ON(in_atomic());
+
+ /*
+ * Now that the whole userspace is frozen we need to disbale
+ * the OOM killer to disallow any further interference with
+ * killable tasks. There is no guarantee oom victims will
+ * ever reach a point they go away we have to wait with a timeout.
+ */
+ if (!error && !oom_killer_disable(msecs_to_jiffies(freeze_timeout_msecs)))
+ error = -EBUSY;
+
+ if (error)
+ thaw_processes();
+ return error;
+}
+
+/**
+ * freeze_kernel_threads - Make freezable kernel threads go to the refrigerator.
+ *
+ * On success, returns 0. On failure, -errno and only the kernel threads are
+ * thawed, so as to give a chance to the caller to do additional cleanups
+ * (if any) before thawing the userspace tasks. So, it is the responsibility
+ * of the caller to thaw the userspace tasks, when the time is right.
+ */
+int freeze_kernel_threads(void)
+{
+ int error;
+
+ pr_info("Freezing remaining freezable tasks ... ");
+
+ pm_nosig_freezing = true;
+ error = try_to_freeze_tasks(false);
+ if (!error)
+ pr_cont("done.");
+
+ pr_cont("\n");
+ BUG_ON(in_atomic());
+
+ if (error)
+ thaw_kernel_threads();
+ return error;
+}
+
+void thaw_processes(void)
+{
+ struct task_struct *g, *p;
+ struct task_struct *curr = current;
+
+ trace_suspend_resume(TPS("thaw_processes"), 0, true);
+ if (pm_freezing)
+ atomic_dec(&system_freezing_cnt);
+ pm_freezing = false;
+ pm_nosig_freezing = false;
+
+ oom_killer_enable();
+
+ pr_info("Restarting tasks ... ");
+
+ __usermodehelper_set_disable_depth(UMH_FREEZING);
+ thaw_workqueues();
+
+ cpuset_wait_for_hotplug();
+
+ read_lock(&tasklist_lock);
+ for_each_process_thread(g, p) {
+ /* No other threads should have PF_SUSPEND_TASK set */
+ WARN_ON((p != curr) && (p->flags & PF_SUSPEND_TASK));
+ __thaw_task(p);
+ }
+ read_unlock(&tasklist_lock);
+
+ WARN_ON(!(curr->flags & PF_SUSPEND_TASK));
+ curr->flags &= ~PF_SUSPEND_TASK;
+
+ usermodehelper_enable();
+
+ schedule();
+ pr_cont("done.\n");
+ trace_suspend_resume(TPS("thaw_processes"), 0, false);
+}
+
+void thaw_kernel_threads(void)
+{
+ struct task_struct *g, *p;
+
+ pm_nosig_freezing = false;
+ pr_info("Restarting kernel threads ... ");
+
+ thaw_workqueues();
+
+ read_lock(&tasklist_lock);
+ for_each_process_thread(g, p) {
+ if (p->flags & (PF_KTHREAD | PF_WQ_WORKER))
+ __thaw_task(p);
+ }
+ read_unlock(&tasklist_lock);
+
+ schedule();
+ pr_cont("done.\n");
+}
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
new file mode 100644
index 0000000..86d72ff
--- /dev/null
+++ b/kernel/power/qos.c
@@ -0,0 +1,714 @@
+/*
+ * This module exposes the interface to kernel space for specifying
+ * QoS dependencies. It provides infrastructure for registration of:
+ *
+ * Dependents on a QoS value : register requests
+ * Watchers of QoS value : get notified when target QoS value changes
+ *
+ * This QoS design is best effort based. Dependents register their QoS needs.
+ * Watchers register to keep track of the current QoS needs of the system.
+ *
+ * There are 3 basic classes of QoS parameter: latency, timeout, throughput
+ * each have defined units:
+ * latency: usec
+ * timeout: usec <-- currently not used.
+ * throughput: kbs (kilo byte / sec)
+ *
+ * There are lists of pm_qos_objects each one wrapping requests, notifiers
+ *
+ * User mode requests on a QOS parameter register themselves to the
+ * subsystem by opening the device node /dev/... and writing there request to
+ * the node. As long as the process holds a file handle open to the node the
+ * client continues to be accounted for. Upon file release the usermode
+ * request is removed and a new qos target is computed. This way when the
+ * request that the application has is cleaned up when closes the file
+ * pointer or exits the pm_qos_object will get an opportunity to clean up.
+ *
+ * Mark Gross <mgross@linux.intel.com>
+ */
+
+/*#define DEBUG*/
+
+#include <linux/pm_qos.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/device.h>
+#include <linux/miscdevice.h>
+#include <linux/string.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include <linux/uaccess.h>
+#include <linux/export.h>
+#include <trace/events/power.h>
+
+/*
+ * locking rule: all changes to constraints or notifiers lists
+ * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock
+ * held, taken with _irqsave. One lock to rule them all
+ */
+struct pm_qos_object {
+ struct pm_qos_constraints *constraints;
+ struct miscdevice pm_qos_power_miscdev;
+ char *name;
+};
+
+static DEFINE_SPINLOCK(pm_qos_lock);
+
+static struct pm_qos_object null_pm_qos;
+
+static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier);
+static struct pm_qos_constraints cpu_dma_constraints = {
+ .list = PLIST_HEAD_INIT(cpu_dma_constraints.list),
+ .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
+ .default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
+ .no_constraint_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
+ .type = PM_QOS_MIN,
+ .notifiers = &cpu_dma_lat_notifier,
+};
+static struct pm_qos_object cpu_dma_pm_qos = {
+ .constraints = &cpu_dma_constraints,
+ .name = "cpu_dma_latency",
+};
+
+static BLOCKING_NOTIFIER_HEAD(network_lat_notifier);
+static struct pm_qos_constraints network_lat_constraints = {
+ .list = PLIST_HEAD_INIT(network_lat_constraints.list),
+ .target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
+ .default_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
+ .no_constraint_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
+ .type = PM_QOS_MIN,
+ .notifiers = &network_lat_notifier,
+};
+static struct pm_qos_object network_lat_pm_qos = {
+ .constraints = &network_lat_constraints,
+ .name = "network_latency",
+};
+
+
+static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier);
+static struct pm_qos_constraints network_tput_constraints = {
+ .list = PLIST_HEAD_INIT(network_tput_constraints.list),
+ .target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
+ .default_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
+ .no_constraint_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
+ .type = PM_QOS_MAX,
+ .notifiers = &network_throughput_notifier,
+};
+static struct pm_qos_object network_throughput_pm_qos = {
+ .constraints = &network_tput_constraints,
+ .name = "network_throughput",
+};
+
+
+static BLOCKING_NOTIFIER_HEAD(memory_bandwidth_notifier);
+static struct pm_qos_constraints memory_bw_constraints = {
+ .list = PLIST_HEAD_INIT(memory_bw_constraints.list),
+ .target_value = PM_QOS_MEMORY_BANDWIDTH_DEFAULT_VALUE,
+ .default_value = PM_QOS_MEMORY_BANDWIDTH_DEFAULT_VALUE,
+ .no_constraint_value = PM_QOS_MEMORY_BANDWIDTH_DEFAULT_VALUE,
+ .type = PM_QOS_SUM,
+ .notifiers = &memory_bandwidth_notifier,
+};
+static struct pm_qos_object memory_bandwidth_pm_qos = {
+ .constraints = &memory_bw_constraints,
+ .name = "memory_bandwidth",
+};
+
+
+static struct pm_qos_object *pm_qos_array[] = {
+ &null_pm_qos,
+ &cpu_dma_pm_qos,
+ &network_lat_pm_qos,
+ &network_throughput_pm_qos,
+ &memory_bandwidth_pm_qos,
+};
+
+static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *f_pos);
+static ssize_t pm_qos_power_read(struct file *filp, char __user *buf,
+ size_t count, loff_t *f_pos);
+static int pm_qos_power_open(struct inode *inode, struct file *filp);
+static int pm_qos_power_release(struct inode *inode, struct file *filp);
+
+static const struct file_operations pm_qos_power_fops = {
+ .write = pm_qos_power_write,
+ .read = pm_qos_power_read,
+ .open = pm_qos_power_open,
+ .release = pm_qos_power_release,
+ .llseek = noop_llseek,
+};
+
+/* unlocked internal variant */
+static inline int pm_qos_get_value(struct pm_qos_constraints *c)
+{
+ struct plist_node *node;
+ int total_value = 0;
+
+ if (plist_head_empty(&c->list))
+ return c->no_constraint_value;
+
+ switch (c->type) {
+ case PM_QOS_MIN:
+ return plist_first(&c->list)->prio;
+
+ case PM_QOS_MAX:
+ return plist_last(&c->list)->prio;
+
+ case PM_QOS_SUM:
+ plist_for_each(node, &c->list)
+ total_value += node->prio;
+
+ return total_value;
+
+ default:
+ /* runtime check for not using enum */
+ BUG();
+ return PM_QOS_DEFAULT_VALUE;
+ }
+}
+
+s32 pm_qos_read_value(struct pm_qos_constraints *c)
+{
+ return c->target_value;
+}
+
+static inline void pm_qos_set_value(struct pm_qos_constraints *c, s32 value)
+{
+ c->target_value = value;
+}
+
+static int pm_qos_dbg_show_requests(struct seq_file *s, void *unused)
+{
+ struct pm_qos_object *qos = (struct pm_qos_object *)s->private;
+ struct pm_qos_constraints *c;
+ struct pm_qos_request *req;
+ char *type;
+ unsigned long flags;
+ int tot_reqs = 0;
+ int active_reqs = 0;
+
+ if (IS_ERR_OR_NULL(qos)) {
+ pr_err("%s: bad qos param!\n", __func__);
+ return -EINVAL;
+ }
+ c = qos->constraints;
+ if (IS_ERR_OR_NULL(c)) {
+ pr_err("%s: Bad constraints on qos?\n", __func__);
+ return -EINVAL;
+ }
+
+ /* Lock to ensure we have a snapshot */
+ spin_lock_irqsave(&pm_qos_lock, flags);
+ if (plist_head_empty(&c->list)) {
+ seq_puts(s, "Empty!\n");
+ goto out;
+ }
+
+ switch (c->type) {
+ case PM_QOS_MIN:
+ type = "Minimum";
+ break;
+ case PM_QOS_MAX:
+ type = "Maximum";
+ break;
+ case PM_QOS_SUM:
+ type = "Sum";
+ break;
+ default:
+ type = "Unknown";
+ }
+
+ plist_for_each_entry(req, &c->list, node) {
+ char *state = "Default";
+
+ if ((req->node).prio != c->default_value) {
+ active_reqs++;
+ state = "Active";
+ }
+ tot_reqs++;
+ seq_printf(s, "%d: %d: %s\n", tot_reqs,
+ (req->node).prio, state);
+ }
+
+ seq_printf(s, "Type=%s, Value=%d, Requests: active=%d / total=%d\n",
+ type, pm_qos_get_value(c), active_reqs, tot_reqs);
+
+out:
+ spin_unlock_irqrestore(&pm_qos_lock, flags);
+ return 0;
+}
+
+static int pm_qos_dbg_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, pm_qos_dbg_show_requests,
+ inode->i_private);
+}
+
+static const struct file_operations pm_qos_debug_fops = {
+ .open = pm_qos_dbg_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+/**
+ * pm_qos_update_target - manages the constraints list and calls the notifiers
+ * if needed
+ * @c: constraints data struct
+ * @node: request to add to the list, to update or to remove
+ * @action: action to take on the constraints list
+ * @value: value of the request to add or update
+ *
+ * This function returns 1 if the aggregated constraint value has changed, 0
+ * otherwise.
+ */
+int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
+ enum pm_qos_req_action action, int value)
+{
+ unsigned long flags;
+ int prev_value, curr_value, new_value;
+ int ret;
+
+ spin_lock_irqsave(&pm_qos_lock, flags);
+ prev_value = pm_qos_get_value(c);
+ if (value == PM_QOS_DEFAULT_VALUE)
+ new_value = c->default_value;
+ else
+ new_value = value;
+
+ switch (action) {
+ case PM_QOS_REMOVE_REQ:
+ plist_del(node, &c->list);
+ break;
+ case PM_QOS_UPDATE_REQ:
+ /*
+ * to change the list, we atomically remove, reinit
+ * with new value and add, then see if the extremal
+ * changed
+ */
+ plist_del(node, &c->list);
+ /* fall through */
+ case PM_QOS_ADD_REQ:
+ plist_node_init(node, new_value);
+ plist_add(node, &c->list);
+ break;
+ default:
+ /* no action */
+ ;
+ }
+
+ curr_value = pm_qos_get_value(c);
+ pm_qos_set_value(c, curr_value);
+
+ spin_unlock_irqrestore(&pm_qos_lock, flags);
+
+ trace_pm_qos_update_target(action, prev_value, curr_value);
+ if (prev_value != curr_value) {
+ ret = 1;
+ if (c->notifiers)
+ blocking_notifier_call_chain(c->notifiers,
+ (unsigned long)curr_value,
+ NULL);
+ } else {
+ ret = 0;
+ }
+ return ret;
+}
+
+/**
+ * pm_qos_flags_remove_req - Remove device PM QoS flags request.
+ * @pqf: Device PM QoS flags set to remove the request from.
+ * @req: Request to remove from the set.
+ */
+static void pm_qos_flags_remove_req(struct pm_qos_flags *pqf,
+ struct pm_qos_flags_request *req)
+{
+ s32 val = 0;
+
+ list_del(&req->node);
+ list_for_each_entry(req, &pqf->list, node)
+ val |= req->flags;
+
+ pqf->effective_flags = val;
+}
+
+/**
+ * pm_qos_update_flags - Update a set of PM QoS flags.
+ * @pqf: Set of flags to update.
+ * @req: Request to add to the set, to modify, or to remove from the set.
+ * @action: Action to take on the set.
+ * @val: Value of the request to add or modify.
+ *
+ * Update the given set of PM QoS flags and call notifiers if the aggregate
+ * value has changed. Returns 1 if the aggregate constraint value has changed,
+ * 0 otherwise.
+ */
+bool pm_qos_update_flags(struct pm_qos_flags *pqf,
+ struct pm_qos_flags_request *req,
+ enum pm_qos_req_action action, s32 val)
+{
+ unsigned long irqflags;
+ s32 prev_value, curr_value;
+
+ spin_lock_irqsave(&pm_qos_lock, irqflags);
+
+ prev_value = list_empty(&pqf->list) ? 0 : pqf->effective_flags;
+
+ switch (action) {
+ case PM_QOS_REMOVE_REQ:
+ pm_qos_flags_remove_req(pqf, req);
+ break;
+ case PM_QOS_UPDATE_REQ:
+ pm_qos_flags_remove_req(pqf, req);
+ /* fall through */
+ case PM_QOS_ADD_REQ:
+ req->flags = val;
+ INIT_LIST_HEAD(&req->node);
+ list_add_tail(&req->node, &pqf->list);
+ pqf->effective_flags |= val;
+ break;
+ default:
+ /* no action */
+ ;
+ }
+
+ curr_value = list_empty(&pqf->list) ? 0 : pqf->effective_flags;
+
+ spin_unlock_irqrestore(&pm_qos_lock, irqflags);
+
+ trace_pm_qos_update_flags(action, prev_value, curr_value);
+ return prev_value != curr_value;
+}
+
+/**
+ * pm_qos_request - returns current system wide qos expectation
+ * @pm_qos_class: identification of which qos value is requested
+ *
+ * This function returns the current target value.
+ */
+int pm_qos_request(int pm_qos_class)
+{
+ return pm_qos_read_value(pm_qos_array[pm_qos_class]->constraints);
+}
+EXPORT_SYMBOL_GPL(pm_qos_request);
+
+int pm_qos_request_active(struct pm_qos_request *req)
+{
+ return req->pm_qos_class != 0;
+}
+EXPORT_SYMBOL_GPL(pm_qos_request_active);
+
+static void __pm_qos_update_request(struct pm_qos_request *req,
+ s32 new_value)
+{
+ trace_pm_qos_update_request(req->pm_qos_class, new_value);
+
+ if (new_value != req->node.prio)
+ pm_qos_update_target(
+ pm_qos_array[req->pm_qos_class]->constraints,
+ &req->node, PM_QOS_UPDATE_REQ, new_value);
+}
+
+/**
+ * pm_qos_work_fn - the timeout handler of pm_qos_update_request_timeout
+ * @work: work struct for the delayed work (timeout)
+ *
+ * This cancels the timeout request by falling back to the default at timeout.
+ */
+static void pm_qos_work_fn(struct work_struct *work)
+{
+ struct pm_qos_request *req = container_of(to_delayed_work(work),
+ struct pm_qos_request,
+ work);
+
+ __pm_qos_update_request(req, PM_QOS_DEFAULT_VALUE);
+}
+
+/**
+ * pm_qos_add_request - inserts new qos request into the list
+ * @req: pointer to a preallocated handle
+ * @pm_qos_class: identifies which list of qos request to use
+ * @value: defines the qos request
+ *
+ * This function inserts a new entry in the pm_qos_class list of requested qos
+ * performance characteristics. It recomputes the aggregate QoS expectations
+ * for the pm_qos_class of parameters and initializes the pm_qos_request
+ * handle. Caller needs to save this handle for later use in updates and
+ * removal.
+ */
+
+void pm_qos_add_request(struct pm_qos_request *req,
+ int pm_qos_class, s32 value)
+{
+ if (!req) /*guard against callers passing in null */
+ return;
+
+ if (pm_qos_request_active(req)) {
+ WARN(1, KERN_ERR "pm_qos_add_request() called for already added request\n");
+ return;
+ }
+ req->pm_qos_class = pm_qos_class;
+ INIT_DELAYED_WORK(&req->work, pm_qos_work_fn);
+ trace_pm_qos_add_request(pm_qos_class, value);
+ pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints,
+ &req->node, PM_QOS_ADD_REQ, value);
+}
+EXPORT_SYMBOL_GPL(pm_qos_add_request);
+
+/**
+ * pm_qos_update_request - modifies an existing qos request
+ * @req : handle to list element holding a pm_qos request to use
+ * @value: defines the qos request
+ *
+ * Updates an existing qos request for the pm_qos_class of parameters along
+ * with updating the target pm_qos_class value.
+ *
+ * Attempts are made to make this code callable on hot code paths.
+ */
+void pm_qos_update_request(struct pm_qos_request *req,
+ s32 new_value)
+{
+ if (!req) /*guard against callers passing in null */
+ return;
+
+ if (!pm_qos_request_active(req)) {
+ WARN(1, KERN_ERR "pm_qos_update_request() called for unknown object\n");
+ return;
+ }
+
+ cancel_delayed_work_sync(&req->work);
+ __pm_qos_update_request(req, new_value);
+}
+EXPORT_SYMBOL_GPL(pm_qos_update_request);
+
+/**
+ * pm_qos_update_request_timeout - modifies an existing qos request temporarily.
+ * @req : handle to list element holding a pm_qos request to use
+ * @new_value: defines the temporal qos request
+ * @timeout_us: the effective duration of this qos request in usecs.
+ *
+ * After timeout_us, this qos request is cancelled automatically.
+ */
+void pm_qos_update_request_timeout(struct pm_qos_request *req, s32 new_value,
+ unsigned long timeout_us)
+{
+ if (!req)
+ return;
+ if (WARN(!pm_qos_request_active(req),
+ "%s called for unknown object.", __func__))
+ return;
+
+ cancel_delayed_work_sync(&req->work);
+
+ trace_pm_qos_update_request_timeout(req->pm_qos_class,
+ new_value, timeout_us);
+ if (new_value != req->node.prio)
+ pm_qos_update_target(
+ pm_qos_array[req->pm_qos_class]->constraints,
+ &req->node, PM_QOS_UPDATE_REQ, new_value);
+
+ schedule_delayed_work(&req->work, usecs_to_jiffies(timeout_us));
+}
+
+/**
+ * pm_qos_remove_request - modifies an existing qos request
+ * @req: handle to request list element
+ *
+ * Will remove pm qos request from the list of constraints and
+ * recompute the current target value for the pm_qos_class. Call this
+ * on slow code paths.
+ */
+void pm_qos_remove_request(struct pm_qos_request *req)
+{
+ if (!req) /*guard against callers passing in null */
+ return;
+ /* silent return to keep pcm code cleaner */
+
+ if (!pm_qos_request_active(req)) {
+ WARN(1, KERN_ERR "pm_qos_remove_request() called for unknown object\n");
+ return;
+ }
+
+ cancel_delayed_work_sync(&req->work);
+
+ trace_pm_qos_remove_request(req->pm_qos_class, PM_QOS_DEFAULT_VALUE);
+ pm_qos_update_target(pm_qos_array[req->pm_qos_class]->constraints,
+ &req->node, PM_QOS_REMOVE_REQ,
+ PM_QOS_DEFAULT_VALUE);
+ memset(req, 0, sizeof(*req));
+}
+EXPORT_SYMBOL_GPL(pm_qos_remove_request);
+
+/**
+ * pm_qos_add_notifier - sets notification entry for changes to target value
+ * @pm_qos_class: identifies which qos target changes should be notified.
+ * @notifier: notifier block managed by caller.
+ *
+ * will register the notifier into a notification chain that gets called
+ * upon changes to the pm_qos_class target value.
+ */
+int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier)
+{
+ int retval;
+
+ retval = blocking_notifier_chain_register(
+ pm_qos_array[pm_qos_class]->constraints->notifiers,
+ notifier);
+
+ return retval;
+}
+EXPORT_SYMBOL_GPL(pm_qos_add_notifier);
+
+/**
+ * pm_qos_remove_notifier - deletes notification entry from chain.
+ * @pm_qos_class: identifies which qos target changes are notified.
+ * @notifier: notifier block to be removed.
+ *
+ * will remove the notifier from the notification chain that gets called
+ * upon changes to the pm_qos_class target value.
+ */
+int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier)
+{
+ int retval;
+
+ retval = blocking_notifier_chain_unregister(
+ pm_qos_array[pm_qos_class]->constraints->notifiers,
+ notifier);
+
+ return retval;
+}
+EXPORT_SYMBOL_GPL(pm_qos_remove_notifier);
+
+/* User space interface to PM QoS classes via misc devices */
+static int register_pm_qos_misc(struct pm_qos_object *qos, struct dentry *d)
+{
+ qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR;
+ qos->pm_qos_power_miscdev.name = qos->name;
+ qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops;
+
+ if (d) {
+ (void)debugfs_create_file(qos->name, S_IRUGO, d,
+ (void *)qos, &pm_qos_debug_fops);
+ }
+
+ return misc_register(&qos->pm_qos_power_miscdev);
+}
+
+static int find_pm_qos_object_by_minor(int minor)
+{
+ int pm_qos_class;
+
+ for (pm_qos_class = PM_QOS_CPU_DMA_LATENCY;
+ pm_qos_class < PM_QOS_NUM_CLASSES; pm_qos_class++) {
+ if (minor ==
+ pm_qos_array[pm_qos_class]->pm_qos_power_miscdev.minor)
+ return pm_qos_class;
+ }
+ return -1;
+}
+
+static int pm_qos_power_open(struct inode *inode, struct file *filp)
+{
+ long pm_qos_class;
+
+ pm_qos_class = find_pm_qos_object_by_minor(iminor(inode));
+ if (pm_qos_class >= PM_QOS_CPU_DMA_LATENCY) {
+ struct pm_qos_request *req = kzalloc(sizeof(*req), GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
+
+ pm_qos_add_request(req, pm_qos_class, PM_QOS_DEFAULT_VALUE);
+ filp->private_data = req;
+
+ return 0;
+ }
+ return -EPERM;
+}
+
+static int pm_qos_power_release(struct inode *inode, struct file *filp)
+{
+ struct pm_qos_request *req;
+
+ req = filp->private_data;
+ pm_qos_remove_request(req);
+ kfree(req);
+
+ return 0;
+}
+
+
+static ssize_t pm_qos_power_read(struct file *filp, char __user *buf,
+ size_t count, loff_t *f_pos)
+{
+ s32 value;
+ unsigned long flags;
+ struct pm_qos_request *req = filp->private_data;
+
+ if (!req)
+ return -EINVAL;
+ if (!pm_qos_request_active(req))
+ return -EINVAL;
+
+ spin_lock_irqsave(&pm_qos_lock, flags);
+ value = pm_qos_get_value(pm_qos_array[req->pm_qos_class]->constraints);
+ spin_unlock_irqrestore(&pm_qos_lock, flags);
+
+ return simple_read_from_buffer(buf, count, f_pos, &value, sizeof(s32));
+}
+
+static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *f_pos)
+{
+ s32 value;
+ struct pm_qos_request *req;
+
+ if (count == sizeof(s32)) {
+ if (copy_from_user(&value, buf, sizeof(s32)))
+ return -EFAULT;
+ } else {
+ int ret;
+
+ ret = kstrtos32_from_user(buf, count, 16, &value);
+ if (ret)
+ return ret;
+ }
+
+ req = filp->private_data;
+ pm_qos_update_request(req, value);
+
+ return count;
+}
+
+
+static int __init pm_qos_power_init(void)
+{
+ int ret = 0;
+ int i;
+ struct dentry *d;
+
+ BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES);
+
+ d = debugfs_create_dir("pm_qos", NULL);
+ if (IS_ERR_OR_NULL(d))
+ d = NULL;
+
+ for (i = PM_QOS_CPU_DMA_LATENCY; i < PM_QOS_NUM_CLASSES; i++) {
+ ret = register_pm_qos_misc(pm_qos_array[i], d);
+ if (ret < 0) {
+ pr_err("%s: %s setup failed\n",
+ __func__, pm_qos_array[i]->name);
+ return ret;
+ }
+ }
+
+ return ret;
+}
+
+late_initcall(pm_qos_power_init);
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
new file mode 100644
index 0000000..3d37c27
--- /dev/null
+++ b/kernel/power/snapshot.c
@@ -0,0 +1,2719 @@
+/*
+ * linux/kernel/power/snapshot.c
+ *
+ * This file provides system snapshot/restore functionality for swsusp.
+ *
+ * Copyright (C) 1998-2005 Pavel Machek <pavel@ucw.cz>
+ * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
+ *
+ * This file is released under the GPLv2.
+ *
+ */
+
+#define pr_fmt(fmt) "PM: " fmt
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/suspend.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/spinlock.h>
+#include <linux/kernel.h>
+#include <linux/pm.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/nmi.h>
+#include <linux/syscalls.h>
+#include <linux/console.h>
+#include <linux/highmem.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/compiler.h>
+#include <linux/ktime.h>
+#include <linux/set_memory.h>
+
+#include <linux/uaccess.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+#include <asm/io.h>
+
+#include "power.h"
+
+#if defined(CONFIG_STRICT_KERNEL_RWX) && defined(CONFIG_ARCH_HAS_SET_MEMORY)
+static bool hibernate_restore_protection;
+static bool hibernate_restore_protection_active;
+
+void enable_restore_image_protection(void)
+{
+ hibernate_restore_protection = true;
+}
+
+static inline void hibernate_restore_protection_begin(void)
+{
+ hibernate_restore_protection_active = hibernate_restore_protection;
+}
+
+static inline void hibernate_restore_protection_end(void)
+{
+ hibernate_restore_protection_active = false;
+}
+
+static inline void hibernate_restore_protect_page(void *page_address)
+{
+ if (hibernate_restore_protection_active)
+ set_memory_ro((unsigned long)page_address, 1);
+}
+
+static inline void hibernate_restore_unprotect_page(void *page_address)
+{
+ if (hibernate_restore_protection_active)
+ set_memory_rw((unsigned long)page_address, 1);
+}
+#else
+static inline void hibernate_restore_protection_begin(void) {}
+static inline void hibernate_restore_protection_end(void) {}
+static inline void hibernate_restore_protect_page(void *page_address) {}
+static inline void hibernate_restore_unprotect_page(void *page_address) {}
+#endif /* CONFIG_STRICT_KERNEL_RWX && CONFIG_ARCH_HAS_SET_MEMORY */
+
+static int swsusp_page_is_free(struct page *);
+static void swsusp_set_page_forbidden(struct page *);
+static void swsusp_unset_page_forbidden(struct page *);
+
+/*
+ * Number of bytes to reserve for memory allocations made by device drivers
+ * from their ->freeze() and ->freeze_noirq() callbacks so that they don't
+ * cause image creation to fail (tunable via /sys/power/reserved_size).
+ */
+unsigned long reserved_size;
+
+void __init hibernate_reserved_size_init(void)
+{
+ reserved_size = SPARE_PAGES * PAGE_SIZE;
+}
+
+/*
+ * 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;
+
+void __init hibernate_image_size_init(void)
+{
+ image_size = ((totalram_pages * 2) / 5) * PAGE_SIZE;
+}
+
+/*
+ * 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
+ * directly to their "original" page frames.
+ */
+struct pbe *restore_pblist;
+
+/* struct linked_page is used to build chains of pages */
+
+#define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *))
+
+struct linked_page {
+ struct linked_page *next;
+ char data[LINKED_PAGE_DATA_SIZE];
+} __packed;
+
+/*
+ * List of "safe" pages (ie. pages that were not used by the image kernel
+ * before hibernation) that may be used as temporary storage for image kernel
+ * memory contents.
+ */
+static struct linked_page *safe_pages_list;
+
+/* Pointer to an auxiliary buffer (1 page) */
+static void *buffer;
+
+#define PG_ANY 0
+#define PG_SAFE 1
+#define PG_UNSAFE_CLEAR 1
+#define PG_UNSAFE_KEEP 0
+
+static unsigned int allocated_unsafe_pages;
+
+/**
+ * get_image_page - Allocate a page for a hibernation image.
+ * @gfp_mask: GFP mask for the allocation.
+ * @safe_needed: Get pages that were not used before hibernation (restore only)
+ *
+ * During image restoration, for storing the PBE list and the image data, we can
+ * only use memory pages that do not conflict with the pages used before
+ * hibernation. The "unsafe" pages have PageNosaveFree set and we count them
+ * using allocated_unsafe_pages.
+ *
+ * Each allocated image page is marked as PageNosave and PageNosaveFree so that
+ * swsusp_free() can release it.
+ */
+static void *get_image_page(gfp_t gfp_mask, int safe_needed)
+{
+ void *res;
+
+ res = (void *)get_zeroed_page(gfp_mask);
+ if (safe_needed)
+ while (res && swsusp_page_is_free(virt_to_page(res))) {
+ /* The page is unsafe, mark it for swsusp_free() */
+ swsusp_set_page_forbidden(virt_to_page(res));
+ allocated_unsafe_pages++;
+ res = (void *)get_zeroed_page(gfp_mask);
+ }
+ if (res) {
+ swsusp_set_page_forbidden(virt_to_page(res));
+ swsusp_set_page_free(virt_to_page(res));
+ }
+ return res;
+}
+
+static void *__get_safe_page(gfp_t gfp_mask)
+{
+ if (safe_pages_list) {
+ void *ret = safe_pages_list;
+
+ safe_pages_list = safe_pages_list->next;
+ memset(ret, 0, PAGE_SIZE);
+ return ret;
+ }
+ return get_image_page(gfp_mask, PG_SAFE);
+}
+
+unsigned long get_safe_page(gfp_t gfp_mask)
+{
+ return (unsigned long)__get_safe_page(gfp_mask);
+}
+
+static struct page *alloc_image_page(gfp_t gfp_mask)
+{
+ struct page *page;
+
+ page = alloc_page(gfp_mask);
+ if (page) {
+ swsusp_set_page_forbidden(page);
+ swsusp_set_page_free(page);
+ }
+ return page;
+}
+
+static void recycle_safe_page(void *page_address)
+{
+ struct linked_page *lp = page_address;
+
+ lp->next = safe_pages_list;
+ safe_pages_list = lp;
+}
+
+/**
+ * free_image_page - Free a page allocated for hibernation image.
+ * @addr: Address of the page to free.
+ * @clear_nosave_free: If set, clear the PageNosaveFree bit for the page.
+ *
+ * The page to free should have been allocated by get_image_page() (page flags
+ * set by it are affected).
+ */
+static inline void free_image_page(void *addr, int clear_nosave_free)
+{
+ struct page *page;
+
+ BUG_ON(!virt_addr_valid(addr));
+
+ page = virt_to_page(addr);
+
+ swsusp_unset_page_forbidden(page);
+ if (clear_nosave_free)
+ swsusp_unset_page_free(page);
+
+ __free_page(page);
+}
+
+static inline void free_list_of_pages(struct linked_page *list,
+ int clear_page_nosave)
+{
+ while (list) {
+ struct linked_page *lp = list->next;
+
+ free_image_page(list, clear_page_nosave);
+ list = lp;
+ }
+}
+
+/*
+ * struct chain_allocator is used for allocating small objects out of
+ * a linked list of pages called 'the chain'.
+ *
+ * The chain grows each time when there is no room for a new object in
+ * the current page. The allocated objects cannot be freed individually.
+ * It is only possible to free them all at once, by freeing the entire
+ * chain.
+ *
+ * NOTE: The chain allocator may be inefficient if the allocated objects
+ * are not much smaller than PAGE_SIZE.
+ */
+struct chain_allocator {
+ struct linked_page *chain; /* the chain */
+ unsigned int used_space; /* total size of objects allocated out
+ of the current page */
+ gfp_t gfp_mask; /* mask for allocating pages */
+ int safe_needed; /* if set, only "safe" pages are allocated */
+};
+
+static void chain_init(struct chain_allocator *ca, gfp_t gfp_mask,
+ int safe_needed)
+{
+ ca->chain = NULL;
+ ca->used_space = LINKED_PAGE_DATA_SIZE;
+ ca->gfp_mask = gfp_mask;
+ ca->safe_needed = safe_needed;
+}
+
+static void *chain_alloc(struct chain_allocator *ca, unsigned int size)
+{
+ void *ret;
+
+ if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) {
+ struct linked_page *lp;
+
+ lp = ca->safe_needed ? __get_safe_page(ca->gfp_mask) :
+ get_image_page(ca->gfp_mask, PG_ANY);
+ if (!lp)
+ return NULL;
+
+ lp->next = ca->chain;
+ ca->chain = lp;
+ ca->used_space = 0;
+ }
+ ret = ca->chain->data + ca->used_space;
+ ca->used_space += size;
+ return ret;
+}
+
+/**
+ * Data types related to memory bitmaps.
+ *
+ * Memory bitmap is a structure consiting of many linked lists of
+ * objects. The main list's elements are of type struct zone_bitmap
+ * and each of them corresonds to one zone. For each zone bitmap
+ * object there is a list of objects of type struct bm_block that
+ * represent each blocks of bitmap in which information is stored.
+ *
+ * struct memory_bitmap contains a pointer to the main list of zone
+ * bitmap objects, a struct bm_position used for browsing the bitmap,
+ * and a pointer to the list of pages used for allocating all of the
+ * zone bitmap objects and bitmap block objects.
+ *
+ * NOTE: It has to be possible to lay out the bitmap in memory
+ * using only allocations of order 0. Additionally, the bitmap is
+ * designed to work with arbitrary number of zones (this is over the
+ * top for now, but let's avoid making unnecessary assumptions ;-).
+ *
+ * struct zone_bitmap contains a pointer to a list of bitmap block
+ * objects and a pointer to the bitmap block object that has been
+ * most recently used for setting bits. Additionally, it contains the
+ * PFNs that correspond to the start and end of the represented zone.
+ *
+ * struct bm_block contains a pointer to the memory page in which
+ * information is stored (in the form of a block of bitmap)
+ * It also contains the pfns that correspond to the start and end of
+ * the represented memory area.
+ *
+ * The memory bitmap is organized as a radix tree to guarantee fast random
+ * access to the bits. There is one radix tree for each zone (as returned
+ * from create_mem_extents).
+ *
+ * One radix tree is represented by one struct mem_zone_bm_rtree. There are
+ * two linked lists for the nodes of the tree, one for the inner nodes and
+ * one for the leave nodes. The linked leave nodes are used for fast linear
+ * access of the memory bitmap.
+ *
+ * The struct rtree_node represents one node of the radix tree.
+ */
+
+#define BM_END_OF_MAP (~0UL)
+
+#define BM_BITS_PER_BLOCK (PAGE_SIZE * BITS_PER_BYTE)
+#define BM_BLOCK_SHIFT (PAGE_SHIFT + 3)
+#define BM_BLOCK_MASK ((1UL << BM_BLOCK_SHIFT) - 1)
+
+/*
+ * struct rtree_node is a wrapper struct to link the nodes
+ * of the rtree together for easy linear iteration over
+ * bits and easy freeing
+ */
+struct rtree_node {
+ struct list_head list;
+ unsigned long *data;
+};
+
+/*
+ * struct mem_zone_bm_rtree represents a bitmap used for one
+ * populated memory zone.
+ */
+struct mem_zone_bm_rtree {
+ struct list_head list; /* Link Zones together */
+ struct list_head nodes; /* Radix Tree inner nodes */
+ struct list_head leaves; /* Radix Tree leaves */
+ unsigned long start_pfn; /* Zone start page frame */
+ unsigned long end_pfn; /* Zone end page frame + 1 */
+ struct rtree_node *rtree; /* Radix Tree Root */
+ int levels; /* Number of Radix Tree Levels */
+ unsigned int blocks; /* Number of Bitmap Blocks */
+};
+
+/* strcut bm_position is used for browsing memory bitmaps */
+
+struct bm_position {
+ struct mem_zone_bm_rtree *zone;
+ struct rtree_node *node;
+ unsigned long node_pfn;
+ int node_bit;
+};
+
+struct memory_bitmap {
+ struct list_head zones;
+ struct linked_page *p_list; /* list of pages used to store zone
+ bitmap objects and bitmap block
+ objects */
+ struct bm_position cur; /* most recently used bit position */
+};
+
+/* Functions that operate on memory bitmaps */
+
+#define BM_ENTRIES_PER_LEVEL (PAGE_SIZE / sizeof(unsigned long))
+#if BITS_PER_LONG == 32
+#define BM_RTREE_LEVEL_SHIFT (PAGE_SHIFT - 2)
+#else
+#define BM_RTREE_LEVEL_SHIFT (PAGE_SHIFT - 3)
+#endif
+#define BM_RTREE_LEVEL_MASK ((1UL << BM_RTREE_LEVEL_SHIFT) - 1)
+
+/**
+ * alloc_rtree_node - Allocate a new node and add it to the radix tree.
+ *
+ * This function is used to allocate inner nodes as well as the
+ * leave nodes of the radix tree. It also adds the node to the
+ * corresponding linked list passed in by the *list parameter.
+ */
+static struct rtree_node *alloc_rtree_node(gfp_t gfp_mask, int safe_needed,
+ struct chain_allocator *ca,
+ struct list_head *list)
+{
+ struct rtree_node *node;
+
+ node = chain_alloc(ca, sizeof(struct rtree_node));
+ if (!node)
+ return NULL;
+
+ node->data = get_image_page(gfp_mask, safe_needed);
+ if (!node->data)
+ return NULL;
+
+ list_add_tail(&node->list, list);
+
+ return node;
+}
+
+/**
+ * add_rtree_block - Add a new leave node to the radix tree.
+ *
+ * The leave nodes need to be allocated in order to keep the leaves
+ * linked list in order. This is guaranteed by the zone->blocks
+ * counter.
+ */
+static int add_rtree_block(struct mem_zone_bm_rtree *zone, gfp_t gfp_mask,
+ int safe_needed, struct chain_allocator *ca)
+{
+ struct rtree_node *node, *block, **dst;
+ unsigned int levels_needed, block_nr;
+ int i;
+
+ block_nr = zone->blocks;
+ levels_needed = 0;
+
+ /* How many levels do we need for this block nr? */
+ while (block_nr) {
+ levels_needed += 1;
+ block_nr >>= BM_RTREE_LEVEL_SHIFT;
+ }
+
+ /* Make sure the rtree has enough levels */
+ for (i = zone->levels; i < levels_needed; i++) {
+ node = alloc_rtree_node(gfp_mask, safe_needed, ca,
+ &zone->nodes);
+ if (!node)
+ return -ENOMEM;
+
+ node->data[0] = (unsigned long)zone->rtree;
+ zone->rtree = node;
+ zone->levels += 1;
+ }
+
+ /* Allocate new block */
+ block = alloc_rtree_node(gfp_mask, safe_needed, ca, &zone->leaves);
+ if (!block)
+ return -ENOMEM;
+
+ /* Now walk the rtree to insert the block */
+ node = zone->rtree;
+ dst = &zone->rtree;
+ block_nr = zone->blocks;
+ for (i = zone->levels; i > 0; i--) {
+ int index;
+
+ if (!node) {
+ node = alloc_rtree_node(gfp_mask, safe_needed, ca,
+ &zone->nodes);
+ if (!node)
+ return -ENOMEM;
+ *dst = node;
+ }
+
+ index = block_nr >> ((i - 1) * BM_RTREE_LEVEL_SHIFT);
+ index &= BM_RTREE_LEVEL_MASK;
+ dst = (struct rtree_node **)&((*dst)->data[index]);
+ node = *dst;
+ }
+
+ zone->blocks += 1;
+ *dst = block;
+
+ return 0;
+}
+
+static void free_zone_bm_rtree(struct mem_zone_bm_rtree *zone,
+ int clear_nosave_free);
+
+/**
+ * create_zone_bm_rtree - Create a radix tree for one zone.
+ *
+ * Allocated the mem_zone_bm_rtree structure and initializes it.
+ * This function also allocated and builds the radix tree for the
+ * zone.
+ */
+static struct mem_zone_bm_rtree *create_zone_bm_rtree(gfp_t gfp_mask,
+ int safe_needed,
+ struct chain_allocator *ca,
+ unsigned long start,
+ unsigned long end)
+{
+ struct mem_zone_bm_rtree *zone;
+ unsigned int i, nr_blocks;
+ unsigned long pages;
+
+ pages = end - start;
+ zone = chain_alloc(ca, sizeof(struct mem_zone_bm_rtree));
+ if (!zone)
+ return NULL;
+
+ INIT_LIST_HEAD(&zone->nodes);
+ INIT_LIST_HEAD(&zone->leaves);
+ zone->start_pfn = start;
+ zone->end_pfn = end;
+ nr_blocks = DIV_ROUND_UP(pages, BM_BITS_PER_BLOCK);
+
+ for (i = 0; i < nr_blocks; i++) {
+ if (add_rtree_block(zone, gfp_mask, safe_needed, ca)) {
+ free_zone_bm_rtree(zone, PG_UNSAFE_CLEAR);
+ return NULL;
+ }
+ }
+
+ return zone;
+}
+
+/**
+ * free_zone_bm_rtree - Free the memory of the radix tree.
+ *
+ * Free all node pages of the radix tree. The mem_zone_bm_rtree
+ * structure itself is not freed here nor are the rtree_node
+ * structs.
+ */
+static void free_zone_bm_rtree(struct mem_zone_bm_rtree *zone,
+ int clear_nosave_free)
+{
+ struct rtree_node *node;
+
+ list_for_each_entry(node, &zone->nodes, list)
+ free_image_page(node->data, clear_nosave_free);
+
+ list_for_each_entry(node, &zone->leaves, list)
+ free_image_page(node->data, clear_nosave_free);
+}
+
+static void memory_bm_position_reset(struct memory_bitmap *bm)
+{
+ bm->cur.zone = list_entry(bm->zones.next, struct mem_zone_bm_rtree,
+ list);
+ bm->cur.node = list_entry(bm->cur.zone->leaves.next,
+ struct rtree_node, list);
+ bm->cur.node_pfn = 0;
+ bm->cur.node_bit = 0;
+}
+
+static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free);
+
+struct mem_extent {
+ struct list_head hook;
+ unsigned long start;
+ unsigned long end;
+};
+
+/**
+ * free_mem_extents - Free a list of memory extents.
+ * @list: List of extents to free.
+ */
+static void free_mem_extents(struct list_head *list)
+{
+ struct mem_extent *ext, *aux;
+
+ list_for_each_entry_safe(ext, aux, list, hook) {
+ list_del(&ext->hook);
+ kfree(ext);
+ }
+}
+
+/**
+ * create_mem_extents - Create a list of memory extents.
+ * @list: List to put the extents into.
+ * @gfp_mask: Mask to use for memory allocations.
+ *
+ * The extents represent contiguous ranges of PFNs.
+ */
+static int create_mem_extents(struct list_head *list, gfp_t gfp_mask)
+{
+ struct zone *zone;
+
+ INIT_LIST_HEAD(list);
+
+ for_each_populated_zone(zone) {
+ unsigned long zone_start, zone_end;
+ struct mem_extent *ext, *cur, *aux;
+
+ zone_start = zone->zone_start_pfn;
+ zone_end = zone_end_pfn(zone);
+
+ list_for_each_entry(ext, list, hook)
+ if (zone_start <= ext->end)
+ break;
+
+ if (&ext->hook == list || zone_end < ext->start) {
+ /* New extent is necessary */
+ struct mem_extent *new_ext;
+
+ new_ext = kzalloc(sizeof(struct mem_extent), gfp_mask);
+ if (!new_ext) {
+ free_mem_extents(list);
+ return -ENOMEM;
+ }
+ new_ext->start = zone_start;
+ new_ext->end = zone_end;
+ list_add_tail(&new_ext->hook, &ext->hook);
+ continue;
+ }
+
+ /* Merge this zone's range of PFNs with the existing one */
+ if (zone_start < ext->start)
+ ext->start = zone_start;
+ if (zone_end > ext->end)
+ ext->end = zone_end;
+
+ /* More merging may be possible */
+ cur = ext;
+ list_for_each_entry_safe_continue(cur, aux, list, hook) {
+ if (zone_end < cur->start)
+ break;
+ if (zone_end < cur->end)
+ ext->end = cur->end;
+ list_del(&cur->hook);
+ kfree(cur);
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * memory_bm_create - Allocate memory for a memory bitmap.
+ */
+static int memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask,
+ int safe_needed)
+{
+ struct chain_allocator ca;
+ struct list_head mem_extents;
+ struct mem_extent *ext;
+ int error;
+
+ chain_init(&ca, gfp_mask, safe_needed);
+ INIT_LIST_HEAD(&bm->zones);
+
+ error = create_mem_extents(&mem_extents, gfp_mask);
+ if (error)
+ return error;
+
+ list_for_each_entry(ext, &mem_extents, hook) {
+ struct mem_zone_bm_rtree *zone;
+
+ zone = create_zone_bm_rtree(gfp_mask, safe_needed, &ca,
+ ext->start, ext->end);
+ if (!zone) {
+ error = -ENOMEM;
+ goto Error;
+ }
+ list_add_tail(&zone->list, &bm->zones);
+ }
+
+ bm->p_list = ca.chain;
+ memory_bm_position_reset(bm);
+ Exit:
+ free_mem_extents(&mem_extents);
+ return error;
+
+ Error:
+ bm->p_list = ca.chain;
+ memory_bm_free(bm, PG_UNSAFE_CLEAR);
+ goto Exit;
+}
+
+/**
+ * memory_bm_free - Free memory occupied by the memory bitmap.
+ * @bm: Memory bitmap.
+ */
+static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free)
+{
+ struct mem_zone_bm_rtree *zone;
+
+ list_for_each_entry(zone, &bm->zones, list)
+ free_zone_bm_rtree(zone, clear_nosave_free);
+
+ free_list_of_pages(bm->p_list, clear_nosave_free);
+
+ INIT_LIST_HEAD(&bm->zones);
+}
+
+/**
+ * memory_bm_find_bit - Find the bit for a given PFN in a memory bitmap.
+ *
+ * Find the bit in memory bitmap @bm that corresponds to the given PFN.
+ * The cur.zone, cur.block and cur.node_pfn members of @bm are updated.
+ *
+ * Walk the radix tree to find the page containing the bit that represents @pfn
+ * and return the position of the bit in @addr and @bit_nr.
+ */
+static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
+ void **addr, unsigned int *bit_nr)
+{
+ struct mem_zone_bm_rtree *curr, *zone;
+ struct rtree_node *node;
+ int i, block_nr;
+
+ zone = bm->cur.zone;
+
+ if (pfn >= zone->start_pfn && pfn < zone->end_pfn)
+ goto zone_found;
+
+ zone = NULL;
+
+ /* Find the right zone */
+ list_for_each_entry(curr, &bm->zones, list) {
+ if (pfn >= curr->start_pfn && pfn < curr->end_pfn) {
+ zone = curr;
+ break;
+ }
+ }
+
+ if (!zone)
+ return -EFAULT;
+
+zone_found:
+ /*
+ * We have found the zone. Now walk the radix tree to find the leaf node
+ * for our PFN.
+ */
+ node = bm->cur.node;
+ if (((pfn - zone->start_pfn) & ~BM_BLOCK_MASK) == bm->cur.node_pfn)
+ goto node_found;
+
+ node = zone->rtree;
+ block_nr = (pfn - zone->start_pfn) >> BM_BLOCK_SHIFT;
+
+ for (i = zone->levels; i > 0; i--) {
+ int index;
+
+ index = block_nr >> ((i - 1) * BM_RTREE_LEVEL_SHIFT);
+ index &= BM_RTREE_LEVEL_MASK;
+ BUG_ON(node->data[index] == 0);
+ node = (struct rtree_node *)node->data[index];
+ }
+
+node_found:
+ /* Update last position */
+ bm->cur.zone = zone;
+ bm->cur.node = node;
+ bm->cur.node_pfn = (pfn - zone->start_pfn) & ~BM_BLOCK_MASK;
+
+ /* Set return values */
+ *addr = node->data;
+ *bit_nr = (pfn - zone->start_pfn) & BM_BLOCK_MASK;
+
+ return 0;
+}
+
+static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
+{
+ void *addr;
+ unsigned int bit;
+ int error;
+
+ error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error);
+ set_bit(bit, addr);
+}
+
+static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn)
+{
+ void *addr;
+ unsigned int bit;
+ int error;
+
+ error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+ if (!error)
+ set_bit(bit, addr);
+
+ return error;
+}
+
+static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn)
+{
+ void *addr;
+ unsigned int bit;
+ int error;
+
+ error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error);
+ clear_bit(bit, addr);
+}
+
+static void memory_bm_clear_current(struct memory_bitmap *bm)
+{
+ int bit;
+
+ bit = max(bm->cur.node_bit - 1, 0);
+ clear_bit(bit, bm->cur.node->data);
+}
+
+static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn)
+{
+ void *addr;
+ unsigned int bit;
+ int error;
+
+ error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error);
+ return test_bit(bit, addr);
+}
+
+static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn)
+{
+ void *addr;
+ unsigned int bit;
+
+ return !memory_bm_find_bit(bm, pfn, &addr, &bit);
+}
+
+/*
+ * rtree_next_node - Jump to the next leaf node.
+ *
+ * Set the position to the beginning of the next node in the
+ * memory bitmap. This is either the next node in the current
+ * zone's radix tree or the first node in the radix tree of the
+ * next zone.
+ *
+ * Return true if there is a next node, false otherwise.
+ */
+static bool rtree_next_node(struct memory_bitmap *bm)
+{
+ if (!list_is_last(&bm->cur.node->list, &bm->cur.zone->leaves)) {
+ bm->cur.node = list_entry(bm->cur.node->list.next,
+ struct rtree_node, list);
+ bm->cur.node_pfn += BM_BITS_PER_BLOCK;
+ bm->cur.node_bit = 0;
+ touch_softlockup_watchdog();
+ return true;
+ }
+
+ /* No more nodes, goto next zone */
+ if (!list_is_last(&bm->cur.zone->list, &bm->zones)) {
+ bm->cur.zone = list_entry(bm->cur.zone->list.next,
+ struct mem_zone_bm_rtree, list);
+ bm->cur.node = list_entry(bm->cur.zone->leaves.next,
+ struct rtree_node, list);
+ bm->cur.node_pfn = 0;
+ bm->cur.node_bit = 0;
+ return true;
+ }
+
+ /* No more zones */
+ return false;
+}
+
+/**
+ * memory_bm_rtree_next_pfn - Find the next set bit in a memory bitmap.
+ * @bm: Memory bitmap.
+ *
+ * Starting from the last returned position this function searches for the next
+ * set bit in @bm and returns the PFN represented by it. If no more bits are
+ * set, BM_END_OF_MAP is returned.
+ *
+ * It is required to run memory_bm_position_reset() before the first call to
+ * this function for the given memory bitmap.
+ */
+static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm)
+{
+ unsigned long bits, pfn, pages;
+ int bit;
+
+ do {
+ pages = bm->cur.zone->end_pfn - bm->cur.zone->start_pfn;
+ bits = min(pages - bm->cur.node_pfn, BM_BITS_PER_BLOCK);
+ bit = find_next_bit(bm->cur.node->data, bits,
+ bm->cur.node_bit);
+ if (bit < bits) {
+ pfn = bm->cur.zone->start_pfn + bm->cur.node_pfn + bit;
+ bm->cur.node_bit = bit + 1;
+ return pfn;
+ }
+ } while (rtree_next_node(bm));
+
+ return BM_END_OF_MAP;
+}
+
+/*
+ * This structure represents a range of page frames the contents of which
+ * should not be saved during hibernation.
+ */
+struct nosave_region {
+ struct list_head list;
+ unsigned long start_pfn;
+ unsigned long end_pfn;
+};
+
+static LIST_HEAD(nosave_regions);
+
+static void recycle_zone_bm_rtree(struct mem_zone_bm_rtree *zone)
+{
+ struct rtree_node *node;
+
+ list_for_each_entry(node, &zone->nodes, list)
+ recycle_safe_page(node->data);
+
+ list_for_each_entry(node, &zone->leaves, list)
+ recycle_safe_page(node->data);
+}
+
+static void memory_bm_recycle(struct memory_bitmap *bm)
+{
+ struct mem_zone_bm_rtree *zone;
+ struct linked_page *p_list;
+
+ list_for_each_entry(zone, &bm->zones, list)
+ recycle_zone_bm_rtree(zone);
+
+ p_list = bm->p_list;
+ while (p_list) {
+ struct linked_page *lp = p_list;
+
+ p_list = lp->next;
+ recycle_safe_page(lp);
+ }
+}
+
+/**
+ * register_nosave_region - Register a region of unsaveable memory.
+ *
+ * Register a range of page frames the contents of which should not be saved
+ * during hibernation (to be used in the early initialization code).
+ */
+void __init __register_nosave_region(unsigned long start_pfn,
+ unsigned long end_pfn, int use_kmalloc)
+{
+ struct nosave_region *region;
+
+ if (start_pfn >= end_pfn)
+ return;
+
+ if (!list_empty(&nosave_regions)) {
+ /* Try to extend the previous region (they should be sorted) */
+ region = list_entry(nosave_regions.prev,
+ struct nosave_region, list);
+ if (region->end_pfn == start_pfn) {
+ region->end_pfn = end_pfn;
+ goto Report;
+ }
+ }
+ if (use_kmalloc) {
+ /* During init, this shouldn't fail */
+ region = kmalloc(sizeof(struct nosave_region), GFP_KERNEL);
+ BUG_ON(!region);
+ } else {
+ /* This allocation cannot fail */
+ region = memblock_virt_alloc(sizeof(struct nosave_region), 0);
+ }
+ region->start_pfn = start_pfn;
+ region->end_pfn = end_pfn;
+ list_add_tail(®ion->list, &nosave_regions);
+ Report:
+ pr_info("Registered nosave memory: [mem %#010llx-%#010llx]\n",
+ (unsigned long long) start_pfn << PAGE_SHIFT,
+ ((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
+}
+
+/*
+ * Set bits in this map correspond to the page frames the contents of which
+ * should not be saved during the suspend.
+ */
+static struct memory_bitmap *forbidden_pages_map;
+
+/* Set bits in this map correspond to free page frames. */
+static struct memory_bitmap *free_pages_map;
+
+/*
+ * Each page frame allocated for creating the image is marked by setting the
+ * corresponding bits in forbidden_pages_map and free_pages_map simultaneously
+ */
+
+void swsusp_set_page_free(struct page *page)
+{
+ if (free_pages_map)
+ memory_bm_set_bit(free_pages_map, page_to_pfn(page));
+}
+
+static int swsusp_page_is_free(struct page *page)
+{
+ return free_pages_map ?
+ memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0;
+}
+
+void swsusp_unset_page_free(struct page *page)
+{
+ if (free_pages_map)
+ memory_bm_clear_bit(free_pages_map, page_to_pfn(page));
+}
+
+static void swsusp_set_page_forbidden(struct page *page)
+{
+ if (forbidden_pages_map)
+ memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page));
+}
+
+int swsusp_page_is_forbidden(struct page *page)
+{
+ return forbidden_pages_map ?
+ memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0;
+}
+
+static void swsusp_unset_page_forbidden(struct page *page)
+{
+ if (forbidden_pages_map)
+ memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page));
+}
+
+/**
+ * mark_nosave_pages - Mark pages that should not be saved.
+ * @bm: Memory bitmap.
+ *
+ * Set the bits in @bm that correspond to the page frames the contents of which
+ * should not be saved.
+ */
+static void mark_nosave_pages(struct memory_bitmap *bm)
+{
+ struct nosave_region *region;
+
+ if (list_empty(&nosave_regions))
+ return;
+
+ list_for_each_entry(region, &nosave_regions, list) {
+ unsigned long pfn;
+
+ pr_debug("Marking nosave pages: [mem %#010llx-%#010llx]\n",
+ (unsigned long long) region->start_pfn << PAGE_SHIFT,
+ ((unsigned long long) region->end_pfn << PAGE_SHIFT)
+ - 1);
+
+ for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++)
+ if (pfn_valid(pfn)) {
+ /*
+ * It is safe to ignore the result of
+ * mem_bm_set_bit_check() here, since we won't
+ * touch the PFNs for which the error is
+ * returned anyway.
+ */
+ mem_bm_set_bit_check(bm, pfn);
+ }
+ }
+}
+
+/**
+ * create_basic_memory_bitmaps - Create bitmaps to hold basic page information.
+ *
+ * Create bitmaps needed for marking page frames that should not be saved and
+ * free page frames. The forbidden_pages_map and free_pages_map pointers are
+ * only modified if everything goes well, because we don't want the bits to be
+ * touched before both bitmaps are set up.
+ */
+int create_basic_memory_bitmaps(void)
+{
+ struct memory_bitmap *bm1, *bm2;
+ int error = 0;
+
+ if (forbidden_pages_map && free_pages_map)
+ return 0;
+ else
+ BUG_ON(forbidden_pages_map || free_pages_map);
+
+ bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
+ if (!bm1)
+ return -ENOMEM;
+
+ error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY);
+ if (error)
+ goto Free_first_object;
+
+ bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
+ if (!bm2)
+ goto Free_first_bitmap;
+
+ error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY);
+ if (error)
+ goto Free_second_object;
+
+ forbidden_pages_map = bm1;
+ free_pages_map = bm2;
+ mark_nosave_pages(forbidden_pages_map);
+
+ pr_debug("Basic memory bitmaps created\n");
+
+ return 0;
+
+ Free_second_object:
+ kfree(bm2);
+ Free_first_bitmap:
+ memory_bm_free(bm1, PG_UNSAFE_CLEAR);
+ Free_first_object:
+ kfree(bm1);
+ return -ENOMEM;
+}
+
+/**
+ * free_basic_memory_bitmaps - Free memory bitmaps holding basic information.
+ *
+ * Free memory bitmaps allocated by create_basic_memory_bitmaps(). The
+ * auxiliary pointers are necessary so that the bitmaps themselves are not
+ * referred to while they are being freed.
+ */
+void free_basic_memory_bitmaps(void)
+{
+ struct memory_bitmap *bm1, *bm2;
+
+ if (WARN_ON(!(forbidden_pages_map && free_pages_map)))
+ return;
+
+ bm1 = forbidden_pages_map;
+ bm2 = free_pages_map;
+ forbidden_pages_map = NULL;
+ free_pages_map = NULL;
+ memory_bm_free(bm1, PG_UNSAFE_CLEAR);
+ kfree(bm1);
+ memory_bm_free(bm2, PG_UNSAFE_CLEAR);
+ kfree(bm2);
+
+ pr_debug("Basic memory bitmaps freed\n");
+}
+
+void clear_free_pages(void)
+{
+#ifdef CONFIG_PAGE_POISONING_ZERO
+ struct memory_bitmap *bm = free_pages_map;
+ unsigned long pfn;
+
+ if (WARN_ON(!(free_pages_map)))
+ return;
+
+ memory_bm_position_reset(bm);
+ pfn = memory_bm_next_pfn(bm);
+ while (pfn != BM_END_OF_MAP) {
+ if (pfn_valid(pfn))
+ clear_highpage(pfn_to_page(pfn));
+
+ pfn = memory_bm_next_pfn(bm);
+ }
+ memory_bm_position_reset(bm);
+ pr_info("free pages cleared after restore\n");
+#endif /* PAGE_POISONING_ZERO */
+}
+
+/**
+ * snapshot_additional_pages - Estimate the number of extra pages needed.
+ * @zone: Memory zone to carry out the computation for.
+ *
+ * Estimate the number of additional pages needed for setting up a hibernation
+ * image data structures for @zone (usually, the returned value is greater than
+ * the exact number).
+ */
+unsigned int snapshot_additional_pages(struct zone *zone)
+{
+ unsigned int rtree, nodes;
+
+ rtree = nodes = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK);
+ rtree += DIV_ROUND_UP(rtree * sizeof(struct rtree_node),
+ LINKED_PAGE_DATA_SIZE);
+ while (nodes > 1) {
+ nodes = DIV_ROUND_UP(nodes, BM_ENTRIES_PER_LEVEL);
+ rtree += nodes;
+ }
+
+ return 2 * rtree;
+}
+
+#ifdef CONFIG_HIGHMEM
+/**
+ * count_free_highmem_pages - Compute the total number of free highmem pages.
+ *
+ * The returned number is system-wide.
+ */
+static unsigned int count_free_highmem_pages(void)
+{
+ struct zone *zone;
+ unsigned int cnt = 0;
+
+ for_each_populated_zone(zone)
+ if (is_highmem(zone))
+ cnt += zone_page_state(zone, NR_FREE_PAGES);
+
+ return cnt;
+}
+
+/**
+ * saveable_highmem_page - Check if a highmem page is saveable.
+ *
+ * Determine whether a highmem page should be included in a hibernation image.
+ *
+ * We should save the page if it isn't Nosave or NosaveFree, or Reserved,
+ * and it isn't part of a free chunk of pages.
+ */
+static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn)
+{
+ struct page *page;
+
+ if (!pfn_valid(pfn))
+ return NULL;
+
+ page = pfn_to_page(pfn);
+ if (page_zone(page) != zone)
+ return NULL;
+
+ BUG_ON(!PageHighMem(page));
+
+ if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page) ||
+ PageReserved(page))
+ return NULL;
+
+ if (page_is_guard(page))
+ return NULL;
+
+ return page;
+}
+
+/**
+ * count_highmem_pages - Compute the total number of saveable highmem pages.
+ */
+static unsigned int count_highmem_pages(void)
+{
+ struct zone *zone;
+ unsigned int n = 0;
+
+ for_each_populated_zone(zone) {
+ unsigned long pfn, max_zone_pfn;
+
+ if (!is_highmem(zone))
+ continue;
+
+ mark_free_pages(zone);
+ max_zone_pfn = zone_end_pfn(zone);
+ for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
+ if (saveable_highmem_page(zone, pfn))
+ n++;
+ }
+ return n;
+}
+#else
+static inline void *saveable_highmem_page(struct zone *z, unsigned long p)
+{
+ return NULL;
+}
+#endif /* CONFIG_HIGHMEM */
+
+/**
+ * saveable_page - Check if the given page is saveable.
+ *
+ * Determine whether a non-highmem page should be included in a hibernation
+ * image.
+ *
+ * We should save the page if it isn't Nosave, and is not in the range
+ * of pages statically defined as 'unsaveable', and it isn't part of
+ * a free chunk of pages.
+ */
+static struct page *saveable_page(struct zone *zone, unsigned long pfn)
+{
+ struct page *page;
+
+ if (!pfn_valid(pfn))
+ return NULL;
+
+ page = pfn_to_page(pfn);
+ if (page_zone(page) != zone)
+ return NULL;
+
+ BUG_ON(PageHighMem(page));
+
+ if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page))
+ return NULL;
+
+ if (PageReserved(page)
+ && (!kernel_page_present(page) || pfn_is_nosave(pfn)))
+ return NULL;
+
+ if (page_is_guard(page))
+ return NULL;
+
+ return page;
+}
+
+/**
+ * count_data_pages - Compute the total number of saveable non-highmem pages.
+ */
+static unsigned int count_data_pages(void)
+{
+ struct zone *zone;
+ unsigned long pfn, max_zone_pfn;
+ unsigned int n = 0;
+
+ for_each_populated_zone(zone) {
+ if (is_highmem(zone))
+ continue;
+
+ mark_free_pages(zone);
+ max_zone_pfn = zone_end_pfn(zone);
+ for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
+ if (saveable_page(zone, pfn))
+ n++;
+ }
+ return n;
+}
+
+/*
+ * This is needed, because copy_page and memcpy are not usable for copying
+ * task structs.
+ */
+static inline void do_copy_page(long *dst, long *src)
+{
+ int n;
+
+ for (n = PAGE_SIZE / sizeof(long); n; n--)
+ *dst++ = *src++;
+}
+
+/**
+ * safe_copy_page - Copy a page in a safe way.
+ *
+ * Check if the page we are going to copy is marked as present in the kernel
+ * page tables (this always is the case if CONFIG_DEBUG_PAGEALLOC is not set
+ * and in that case kernel_page_present() always returns 'true').
+ */
+static void safe_copy_page(void *dst, struct page *s_page)
+{
+ if (kernel_page_present(s_page)) {
+ do_copy_page(dst, page_address(s_page));
+ } else {
+ kernel_map_pages(s_page, 1, 1);
+ do_copy_page(dst, page_address(s_page));
+ kernel_map_pages(s_page, 1, 0);
+ }
+}
+
+#ifdef CONFIG_HIGHMEM
+static inline struct page *page_is_saveable(struct zone *zone, unsigned long pfn)
+{
+ return is_highmem(zone) ?
+ saveable_highmem_page(zone, pfn) : saveable_page(zone, pfn);
+}
+
+static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
+{
+ struct page *s_page, *d_page;
+ void *src, *dst;
+
+ s_page = pfn_to_page(src_pfn);
+ d_page = pfn_to_page(dst_pfn);
+ if (PageHighMem(s_page)) {
+ src = kmap_atomic(s_page);
+ dst = kmap_atomic(d_page);
+ do_copy_page(dst, src);
+ kunmap_atomic(dst);
+ kunmap_atomic(src);
+ } else {
+ if (PageHighMem(d_page)) {
+ /*
+ * The page pointed to by src may contain some kernel
+ * data modified by kmap_atomic()
+ */
+ safe_copy_page(buffer, s_page);
+ dst = kmap_atomic(d_page);
+ copy_page(dst, buffer);
+ kunmap_atomic(dst);
+ } else {
+ safe_copy_page(page_address(d_page), s_page);
+ }
+ }
+}
+#else
+#define page_is_saveable(zone, pfn) saveable_page(zone, pfn)
+
+static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
+{
+ safe_copy_page(page_address(pfn_to_page(dst_pfn)),
+ pfn_to_page(src_pfn));
+}
+#endif /* CONFIG_HIGHMEM */
+
+static void copy_data_pages(struct memory_bitmap *copy_bm,
+ struct memory_bitmap *orig_bm)
+{
+ struct zone *zone;
+ unsigned long pfn;
+
+ for_each_populated_zone(zone) {
+ unsigned long max_zone_pfn;
+
+ mark_free_pages(zone);
+ max_zone_pfn = zone_end_pfn(zone);
+ for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
+ if (page_is_saveable(zone, pfn))
+ memory_bm_set_bit(orig_bm, pfn);
+ }
+ memory_bm_position_reset(orig_bm);
+ memory_bm_position_reset(copy_bm);
+ for(;;) {
+ pfn = memory_bm_next_pfn(orig_bm);
+ if (unlikely(pfn == BM_END_OF_MAP))
+ break;
+ copy_data_page(memory_bm_next_pfn(copy_bm), pfn);
+ }
+}
+
+/* Total number of image pages */
+static unsigned int nr_copy_pages;
+/* Number of pages needed for saving the original pfns of the image pages */
+static unsigned int nr_meta_pages;
+/*
+ * Numbers of normal and highmem page frames allocated for hibernation image
+ * before suspending devices.
+ */
+static unsigned int alloc_normal, alloc_highmem;
+/*
+ * Memory bitmap used for marking saveable pages (during hibernation) or
+ * hibernation image pages (during restore)
+ */
+static struct memory_bitmap orig_bm;
+/*
+ * Memory bitmap used during hibernation for marking allocated page frames that
+ * will contain copies of saveable pages. During restore it is initially used
+ * for marking hibernation image pages, but then the set bits from it are
+ * duplicated in @orig_bm and it is released. On highmem systems it is next
+ * used for marking "safe" highmem pages, but it has to be reinitialized for
+ * this purpose.
+ */
+static struct memory_bitmap copy_bm;
+
+/**
+ * swsusp_free - Free pages allocated for hibernation image.
+ *
+ * Image pages are alocated before snapshot creation, so they need to be
+ * released after resume.
+ */
+void swsusp_free(void)
+{
+ unsigned long fb_pfn, fr_pfn;
+
+ if (!forbidden_pages_map || !free_pages_map)
+ goto out;
+
+ memory_bm_position_reset(forbidden_pages_map);
+ memory_bm_position_reset(free_pages_map);
+
+loop:
+ fr_pfn = memory_bm_next_pfn(free_pages_map);
+ fb_pfn = memory_bm_next_pfn(forbidden_pages_map);
+
+ /*
+ * Find the next bit set in both bitmaps. This is guaranteed to
+ * terminate when fb_pfn == fr_pfn == BM_END_OF_MAP.
+ */
+ do {
+ if (fb_pfn < fr_pfn)
+ fb_pfn = memory_bm_next_pfn(forbidden_pages_map);
+ if (fr_pfn < fb_pfn)
+ fr_pfn = memory_bm_next_pfn(free_pages_map);
+ } while (fb_pfn != fr_pfn);
+
+ if (fr_pfn != BM_END_OF_MAP && pfn_valid(fr_pfn)) {
+ struct page *page = pfn_to_page(fr_pfn);
+
+ memory_bm_clear_current(forbidden_pages_map);
+ memory_bm_clear_current(free_pages_map);
+ hibernate_restore_unprotect_page(page_address(page));
+ __free_page(page);
+ goto loop;
+ }
+
+out:
+ nr_copy_pages = 0;
+ nr_meta_pages = 0;
+ restore_pblist = NULL;
+ buffer = NULL;
+ alloc_normal = 0;
+ alloc_highmem = 0;
+ hibernate_restore_protection_end();
+}
+
+/* Helper functions used for the shrinking of memory. */
+
+#define GFP_IMAGE (GFP_KERNEL | __GFP_NOWARN)
+
+/**
+ * preallocate_image_pages - Allocate a number of pages for hibernation image.
+ * @nr_pages: Number of page frames to allocate.
+ * @mask: GFP flags to use for the allocation.
+ *
+ * Return value: Number of page frames actually allocated
+ */
+static unsigned long preallocate_image_pages(unsigned long nr_pages, gfp_t mask)
+{
+ unsigned long nr_alloc = 0;
+
+ while (nr_pages > 0) {
+ struct page *page;
+
+ page = alloc_image_page(mask);
+ if (!page)
+ break;
+ memory_bm_set_bit(©_bm, page_to_pfn(page));
+ if (PageHighMem(page))
+ alloc_highmem++;
+ else
+ alloc_normal++;
+ nr_pages--;
+ nr_alloc++;
+ }
+
+ return nr_alloc;
+}
+
+static unsigned long preallocate_image_memory(unsigned long nr_pages,
+ unsigned long avail_normal)
+{
+ unsigned long alloc;
+
+ if (avail_normal <= alloc_normal)
+ return 0;
+
+ alloc = avail_normal - alloc_normal;
+ if (nr_pages < alloc)
+ alloc = nr_pages;
+
+ return preallocate_image_pages(alloc, GFP_IMAGE);
+}
+
+#ifdef CONFIG_HIGHMEM
+static unsigned long preallocate_image_highmem(unsigned long nr_pages)
+{
+ return preallocate_image_pages(nr_pages, GFP_IMAGE | __GFP_HIGHMEM);
+}
+
+/**
+ * __fraction - Compute (an approximation of) x * (multiplier / base).
+ */
+static unsigned long __fraction(u64 x, u64 multiplier, u64 base)
+{
+ x *= multiplier;
+ do_div(x, base);
+ return (unsigned long)x;
+}
+
+static unsigned long preallocate_highmem_fraction(unsigned long nr_pages,
+ unsigned long highmem,
+ unsigned long total)
+{
+ unsigned long alloc = __fraction(nr_pages, highmem, total);
+
+ return preallocate_image_pages(alloc, GFP_IMAGE | __GFP_HIGHMEM);
+}
+#else /* CONFIG_HIGHMEM */
+static inline unsigned long preallocate_image_highmem(unsigned long nr_pages)
+{
+ return 0;
+}
+
+static inline unsigned long preallocate_highmem_fraction(unsigned long nr_pages,
+ unsigned long highmem,
+ unsigned long total)
+{
+ return 0;
+}
+#endif /* CONFIG_HIGHMEM */
+
+/**
+ * free_unnecessary_pages - Release preallocated pages not needed for the image.
+ */
+static unsigned long free_unnecessary_pages(void)
+{
+ unsigned long save, to_free_normal, to_free_highmem, free;
+
+ save = count_data_pages();
+ if (alloc_normal >= save) {
+ to_free_normal = alloc_normal - save;
+ save = 0;
+ } else {
+ to_free_normal = 0;
+ save -= alloc_normal;
+ }
+ save += count_highmem_pages();
+ if (alloc_highmem >= save) {
+ to_free_highmem = alloc_highmem - save;
+ } else {
+ to_free_highmem = 0;
+ save -= alloc_highmem;
+ if (to_free_normal > save)
+ to_free_normal -= save;
+ else
+ to_free_normal = 0;
+ }
+ free = to_free_normal + to_free_highmem;
+
+ memory_bm_position_reset(©_bm);
+
+ while (to_free_normal > 0 || to_free_highmem > 0) {
+ unsigned long pfn = memory_bm_next_pfn(©_bm);
+ struct page *page = pfn_to_page(pfn);
+
+ if (PageHighMem(page)) {
+ if (!to_free_highmem)
+ continue;
+ to_free_highmem--;
+ alloc_highmem--;
+ } else {
+ if (!to_free_normal)
+ continue;
+ to_free_normal--;
+ alloc_normal--;
+ }
+ memory_bm_clear_bit(©_bm, pfn);
+ swsusp_unset_page_forbidden(page);
+ swsusp_unset_page_free(page);
+ __free_page(page);
+ }
+
+ return free;
+}
+
+/**
+ * minimum_image_size - Estimate the minimum acceptable size of an image.
+ * @saveable: Number of saveable pages in the system.
+ *
+ * We want to avoid attempting to free too much memory too hard, so estimate the
+ * minimum acceptable size of a hibernation image to use as the lower limit for
+ * preallocating memory.
+ *
+ * We assume that the minimum image size should be proportional to
+ *
+ * [number of saveable pages] - [number of pages that can be freed in theory]
+ *
+ * where the second term is the sum of (1) reclaimable slab pages, (2) active
+ * and (3) inactive anonymous pages, (4) active and (5) inactive file pages.
+ */
+static unsigned long minimum_image_size(unsigned long saveable)
+{
+ unsigned long size;
+
+ size = global_node_page_state(NR_SLAB_RECLAIMABLE)
+ + global_node_page_state(NR_ACTIVE_ANON)
+ + global_node_page_state(NR_INACTIVE_ANON)
+ + global_node_page_state(NR_ACTIVE_FILE)
+ + global_node_page_state(NR_INACTIVE_FILE);
+
+ return saveable <= size ? 0 : saveable - size;
+}
+
+/**
+ * hibernate_preallocate_memory - Preallocate memory for hibernation image.
+ *
+ * To create a hibernation image it is necessary to make a copy of every page
+ * frame in use. We also need a number of page frames to be free during
+ * hibernation for allocations made while saving the image and for device
+ * drivers, in case they need to allocate memory from their hibernation
+ * callbacks (these two numbers are given by PAGES_FOR_IO (which is a rough
+ * estimate) and reserverd_size divided by PAGE_SIZE (which is tunable through
+ * /sys/power/reserved_size, respectively). To make this happen, we compute the
+ * total number of available page frames and allocate at least
+ *
+ * ([page frames total] + PAGES_FOR_IO + [metadata pages]) / 2
+ * + 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE)
+ *
+ * of them, which corresponds to the maximum size of a hibernation image.
+ *
+ * If image_size is set below the number following from the above formula,
+ * the preallocation of memory is continued until the total number of saveable
+ * pages in the system is below the requested image size or the minimum
+ * acceptable image size returned by minimum_image_size(), whichever is greater.
+ */
+int hibernate_preallocate_memory(void)
+{
+ struct zone *zone;
+ unsigned long saveable, size, max_size, count, highmem, pages = 0;
+ unsigned long alloc, save_highmem, pages_highmem, avail_normal;
+ ktime_t start, stop;
+ int error;
+
+ pr_info("Preallocating image memory... ");
+ start = ktime_get();
+
+ error = memory_bm_create(&orig_bm, GFP_IMAGE, PG_ANY);
+ if (error)
+ goto err_out;
+
+ error = memory_bm_create(©_bm, GFP_IMAGE, PG_ANY);
+ if (error)
+ goto err_out;
+
+ alloc_normal = 0;
+ alloc_highmem = 0;
+
+ /* Count the number of saveable data pages. */
+ save_highmem = count_highmem_pages();
+ saveable = count_data_pages();
+
+ /*
+ * Compute the total number of page frames we can use (count) and the
+ * number of pages needed for image metadata (size).
+ */
+ count = saveable;
+ saveable += save_highmem;
+ highmem = save_highmem;
+ size = 0;
+ for_each_populated_zone(zone) {
+ size += snapshot_additional_pages(zone);
+ if (is_highmem(zone))
+ highmem += zone_page_state(zone, NR_FREE_PAGES);
+ else
+ count += zone_page_state(zone, NR_FREE_PAGES);
+ }
+ avail_normal = count;
+ count += highmem;
+ count -= totalreserve_pages;
+
+ /* Add number of pages required for page keys (s390 only). */
+ size += page_key_additional_pages(saveable);
+
+ /* Compute the maximum number of saveable pages to leave in memory. */
+ max_size = (count - (size + PAGES_FOR_IO)) / 2
+ - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE);
+ /* Compute the desired number of image pages specified by image_size. */
+ size = DIV_ROUND_UP(image_size, PAGE_SIZE);
+ if (size > max_size)
+ size = max_size;
+ /*
+ * If the desired number of image pages is at least as large as the
+ * current number of saveable pages in memory, allocate page frames for
+ * the image and we're done.
+ */
+ if (size >= saveable) {
+ pages = preallocate_image_highmem(save_highmem);
+ pages += preallocate_image_memory(saveable - pages, avail_normal);
+ goto out;
+ }
+
+ /* Estimate the minimum size of the image. */
+ pages = minimum_image_size(saveable);
+ /*
+ * To avoid excessive pressure on the normal zone, leave room in it to
+ * accommodate an image of the minimum size (unless it's already too
+ * small, in which case don't preallocate pages from it at all).
+ */
+ if (avail_normal > pages)
+ avail_normal -= pages;
+ else
+ avail_normal = 0;
+ if (size < pages)
+ size = min_t(unsigned long, pages, max_size);
+
+ /*
+ * Let the memory management subsystem know that we're going to need a
+ * large number of page frames to allocate and make it free some memory.
+ * NOTE: If this is not done, performance will be hurt badly in some
+ * test cases.
+ */
+ shrink_all_memory(saveable - size);
+
+ /*
+ * The number of saveable pages in memory was too high, so apply some
+ * pressure to decrease it. First, make room for the largest possible
+ * image and fail if that doesn't work. Next, try to decrease the size
+ * of the image as much as indicated by 'size' using allocations from
+ * highmem and non-highmem zones separately.
+ */
+ pages_highmem = preallocate_image_highmem(highmem / 2);
+ alloc = count - max_size;
+ if (alloc > pages_highmem)
+ alloc -= pages_highmem;
+ else
+ alloc = 0;
+ pages = preallocate_image_memory(alloc, avail_normal);
+ if (pages < alloc) {
+ /* We have exhausted non-highmem pages, try highmem. */
+ alloc -= pages;
+ pages += pages_highmem;
+ pages_highmem = preallocate_image_highmem(alloc);
+ if (pages_highmem < alloc)
+ goto err_out;
+ pages += pages_highmem;
+ /*
+ * size is the desired number of saveable pages to leave in
+ * memory, so try to preallocate (all memory - size) pages.
+ */
+ alloc = (count - pages) - size;
+ pages += preallocate_image_highmem(alloc);
+ } else {
+ /*
+ * There are approximately max_size saveable pages at this point
+ * and we want to reduce this number down to size.
+ */
+ alloc = max_size - size;
+ size = preallocate_highmem_fraction(alloc, highmem, count);
+ pages_highmem += size;
+ alloc -= size;
+ size = preallocate_image_memory(alloc, avail_normal);
+ pages_highmem += preallocate_image_highmem(alloc - size);
+ pages += pages_highmem + size;
+ }
+
+ /*
+ * We only need as many page frames for the image as there are saveable
+ * pages in memory, but we have allocated more. Release the excessive
+ * ones now.
+ */
+ pages -= free_unnecessary_pages();
+
+ out:
+ stop = ktime_get();
+ pr_cont("done (allocated %lu pages)\n", pages);
+ swsusp_show_speed(start, stop, pages, "Allocated");
+
+ return 0;
+
+ err_out:
+ pr_cont("\n");
+ swsusp_free();
+ return -ENOMEM;
+}
+
+#ifdef CONFIG_HIGHMEM
+/**
+ * count_pages_for_highmem - Count non-highmem pages needed for copying highmem.
+ *
+ * Compute the number of non-highmem pages that will be necessary for creating
+ * copies of highmem pages.
+ */
+static unsigned int count_pages_for_highmem(unsigned int nr_highmem)
+{
+ unsigned int free_highmem = count_free_highmem_pages() + alloc_highmem;
+
+ if (free_highmem >= nr_highmem)
+ nr_highmem = 0;
+ else
+ nr_highmem -= free_highmem;
+
+ return nr_highmem;
+}
+#else
+static unsigned int count_pages_for_highmem(unsigned int nr_highmem) { return 0; }
+#endif /* CONFIG_HIGHMEM */
+
+/**
+ * enough_free_mem - Check if there is enough free memory for the image.
+ */
+static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem)
+{
+ struct zone *zone;
+ unsigned int free = alloc_normal;
+
+ for_each_populated_zone(zone)
+ if (!is_highmem(zone))
+ free += zone_page_state(zone, NR_FREE_PAGES);
+
+ nr_pages += count_pages_for_highmem(nr_highmem);
+ pr_debug("Normal pages needed: %u + %u, available pages: %u\n",
+ nr_pages, PAGES_FOR_IO, free);
+
+ return free > nr_pages + PAGES_FOR_IO;
+}
+
+#ifdef CONFIG_HIGHMEM
+/**
+ * get_highmem_buffer - Allocate a buffer for highmem pages.
+ *
+ * If there are some highmem pages in the hibernation image, we may need a
+ * buffer to copy them and/or load their data.
+ */
+static inline int get_highmem_buffer(int safe_needed)
+{
+ buffer = get_image_page(GFP_ATOMIC, safe_needed);
+ return buffer ? 0 : -ENOMEM;
+}
+
+/**
+ * alloc_highmem_image_pages - Allocate some highmem pages for the image.
+ *
+ * Try to allocate as many pages as needed, but if the number of free highmem
+ * pages is less than that, allocate them all.
+ */
+static inline unsigned int alloc_highmem_pages(struct memory_bitmap *bm,
+ unsigned int nr_highmem)
+{
+ unsigned int to_alloc = count_free_highmem_pages();
+
+ if (to_alloc > nr_highmem)
+ to_alloc = nr_highmem;
+
+ nr_highmem -= to_alloc;
+ while (to_alloc-- > 0) {
+ struct page *page;
+
+ page = alloc_image_page(__GFP_HIGHMEM|__GFP_KSWAPD_RECLAIM);
+ memory_bm_set_bit(bm, page_to_pfn(page));
+ }
+ return nr_highmem;
+}
+#else
+static inline int get_highmem_buffer(int safe_needed) { return 0; }
+
+static inline unsigned int alloc_highmem_pages(struct memory_bitmap *bm,
+ unsigned int n) { return 0; }
+#endif /* CONFIG_HIGHMEM */
+
+/**
+ * swsusp_alloc - Allocate memory for hibernation image.
+ *
+ * We first try to allocate as many highmem pages as there are
+ * saveable highmem pages in the system. If that fails, we allocate
+ * non-highmem pages for the copies of the remaining highmem ones.
+ *
+ * In this approach it is likely that the copies of highmem pages will
+ * also be located in the high memory, because of the way in which
+ * copy_data_pages() works.
+ */
+static int swsusp_alloc(struct memory_bitmap *copy_bm,
+ unsigned int nr_pages, unsigned int nr_highmem)
+{
+ if (nr_highmem > 0) {
+ if (get_highmem_buffer(PG_ANY))
+ goto err_out;
+ if (nr_highmem > alloc_highmem) {
+ nr_highmem -= alloc_highmem;
+ nr_pages += alloc_highmem_pages(copy_bm, nr_highmem);
+ }
+ }
+ if (nr_pages > alloc_normal) {
+ nr_pages -= alloc_normal;
+ while (nr_pages-- > 0) {
+ struct page *page;
+
+ page = alloc_image_page(GFP_ATOMIC);
+ if (!page)
+ goto err_out;
+ memory_bm_set_bit(copy_bm, page_to_pfn(page));
+ }
+ }
+
+ return 0;
+
+ err_out:
+ swsusp_free();
+ return -ENOMEM;
+}
+
+asmlinkage __visible int swsusp_save(void)
+{
+ unsigned int nr_pages, nr_highmem;
+
+ pr_info("Creating hibernation image:\n");
+
+ drain_local_pages(NULL);
+ nr_pages = count_data_pages();
+ nr_highmem = count_highmem_pages();
+ pr_info("Need to copy %u pages\n", nr_pages + nr_highmem);
+
+ if (!enough_free_mem(nr_pages, nr_highmem)) {
+ pr_err("Not enough free memory\n");
+ return -ENOMEM;
+ }
+
+ if (swsusp_alloc(©_bm, nr_pages, nr_highmem)) {
+ pr_err("Memory allocation failed\n");
+ return -ENOMEM;
+ }
+
+ /*
+ * During allocating of suspend pagedir, new cold pages may appear.
+ * Kill them.
+ */
+ drain_local_pages(NULL);
+ copy_data_pages(©_bm, &orig_bm);
+
+ /*
+ * End of critical section. From now on, we can write to memory,
+ * but we should not touch disk. This specially means we must _not_
+ * touch swap space! Except we must write out our image of course.
+ */
+
+ nr_pages += nr_highmem;
+ nr_copy_pages = nr_pages;
+ nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE);
+
+ pr_info("Hibernation image created (%d pages copied)\n", nr_pages);
+
+ return 0;
+}
+
+#ifndef CONFIG_ARCH_HIBERNATION_HEADER
+static int init_header_complete(struct swsusp_info *info)
+{
+ memcpy(&info->uts, init_utsname(), sizeof(struct new_utsname));
+ info->version_code = LINUX_VERSION_CODE;
+ return 0;
+}
+
+static char *check_image_kernel(struct swsusp_info *info)
+{
+ if (info->version_code != LINUX_VERSION_CODE)
+ return "kernel version";
+ if (strcmp(info->uts.sysname,init_utsname()->sysname))
+ return "system type";
+ if (strcmp(info->uts.release,init_utsname()->release))
+ return "kernel release";
+ if (strcmp(info->uts.version,init_utsname()->version))
+ return "version";
+ if (strcmp(info->uts.machine,init_utsname()->machine))
+ return "machine";
+ return NULL;
+}
+#endif /* CONFIG_ARCH_HIBERNATION_HEADER */
+
+unsigned long snapshot_get_image_size(void)
+{
+ return nr_copy_pages + nr_meta_pages + 1;
+}
+
+static int init_header(struct swsusp_info *info)
+{
+ memset(info, 0, sizeof(struct swsusp_info));
+ info->num_physpages = get_num_physpages();
+ info->image_pages = nr_copy_pages;
+ info->pages = snapshot_get_image_size();
+ info->size = info->pages;
+ info->size <<= PAGE_SHIFT;
+ return init_header_complete(info);
+}
+
+/**
+ * pack_pfns - Prepare PFNs for saving.
+ * @bm: Memory bitmap.
+ * @buf: Memory buffer to store the PFNs in.
+ *
+ * PFNs corresponding to set bits in @bm are stored in the area of memory
+ * pointed to by @buf (1 page at a time).
+ */
+static inline void pack_pfns(unsigned long *buf, struct memory_bitmap *bm)
+{
+ int j;
+
+ for (j = 0; j < PAGE_SIZE / sizeof(long); j++) {
+ buf[j] = memory_bm_next_pfn(bm);
+ if (unlikely(buf[j] == BM_END_OF_MAP))
+ break;
+ /* Save page key for data page (s390 only). */
+ page_key_read(buf + j);
+ }
+}
+
+/**
+ * snapshot_read_next - Get the address to read the next image page from.
+ * @handle: Snapshot handle to be used for the reading.
+ *
+ * On the first call, @handle should point to a zeroed snapshot_handle
+ * structure. The structure gets populated then and a pointer to it should be
+ * passed to this function every next time.
+ *
+ * On success, the function returns a positive number. Then, the caller
+ * is allowed to read up to the returned number of bytes from the memory
+ * location computed by the data_of() macro.
+ *
+ * The function returns 0 to indicate the end of the data stream condition,
+ * and negative numbers are returned on errors. If that happens, the structure
+ * pointed to by @handle is not updated and should not be used any more.
+ */
+int snapshot_read_next(struct snapshot_handle *handle)
+{
+ if (handle->cur > nr_meta_pages + nr_copy_pages)
+ return 0;
+
+ if (!buffer) {
+ /* This makes the buffer be freed by swsusp_free() */
+ buffer = get_image_page(GFP_ATOMIC, PG_ANY);
+ if (!buffer)
+ return -ENOMEM;
+ }
+ if (!handle->cur) {
+ int error;
+
+ error = init_header((struct swsusp_info *)buffer);
+ if (error)
+ return error;
+ handle->buffer = buffer;
+ memory_bm_position_reset(&orig_bm);
+ memory_bm_position_reset(©_bm);
+ } else if (handle->cur <= nr_meta_pages) {
+ clear_page(buffer);
+ pack_pfns(buffer, &orig_bm);
+ } else {
+ struct page *page;
+
+ page = pfn_to_page(memory_bm_next_pfn(©_bm));
+ if (PageHighMem(page)) {
+ /*
+ * Highmem pages are copied to the buffer,
+ * because we can't return with a kmapped
+ * highmem page (we may not be called again).
+ */
+ void *kaddr;
+
+ kaddr = kmap_atomic(page);
+ copy_page(buffer, kaddr);
+ kunmap_atomic(kaddr);
+ handle->buffer = buffer;
+ } else {
+ handle->buffer = page_address(page);
+ }
+ }
+ handle->cur++;
+ return PAGE_SIZE;
+}
+
+static void duplicate_memory_bitmap(struct memory_bitmap *dst,
+ struct memory_bitmap *src)
+{
+ unsigned long pfn;
+
+ memory_bm_position_reset(src);
+ pfn = memory_bm_next_pfn(src);
+ while (pfn != BM_END_OF_MAP) {
+ memory_bm_set_bit(dst, pfn);
+ pfn = memory_bm_next_pfn(src);
+ }
+}
+
+/**
+ * mark_unsafe_pages - Mark pages that were used before hibernation.
+ *
+ * Mark the pages that cannot be used for storing the image during restoration,
+ * because they conflict with the pages that had been used before hibernation.
+ */
+static void mark_unsafe_pages(struct memory_bitmap *bm)
+{
+ unsigned long pfn;
+
+ /* Clear the "free"/"unsafe" bit for all PFNs */
+ memory_bm_position_reset(free_pages_map);
+ pfn = memory_bm_next_pfn(free_pages_map);
+ while (pfn != BM_END_OF_MAP) {
+ memory_bm_clear_current(free_pages_map);
+ pfn = memory_bm_next_pfn(free_pages_map);
+ }
+
+ /* Mark pages that correspond to the "original" PFNs as "unsafe" */
+ duplicate_memory_bitmap(free_pages_map, bm);
+
+ allocated_unsafe_pages = 0;
+}
+
+static int check_header(struct swsusp_info *info)
+{
+ char *reason;
+
+ reason = check_image_kernel(info);
+ if (!reason && info->num_physpages != get_num_physpages())
+ reason = "memory size";
+ if (reason) {
+ pr_err("Image mismatch: %s\n", reason);
+ return -EPERM;
+ }
+ return 0;
+}
+
+/**
+ * load header - Check the image header and copy the data from it.
+ */
+static int load_header(struct swsusp_info *info)
+{
+ int error;
+
+ restore_pblist = NULL;
+ error = check_header(info);
+ if (!error) {
+ nr_copy_pages = info->image_pages;
+ nr_meta_pages = info->pages - info->image_pages - 1;
+ }
+ return error;
+}
+
+/**
+ * unpack_orig_pfns - Set bits corresponding to given PFNs in a memory bitmap.
+ * @bm: Memory bitmap.
+ * @buf: Area of memory containing the PFNs.
+ *
+ * For each element of the array pointed to by @buf (1 page at a time), set the
+ * corresponding bit in @bm.
+ */
+static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm)
+{
+ int j;
+
+ for (j = 0; j < PAGE_SIZE / sizeof(long); j++) {
+ if (unlikely(buf[j] == BM_END_OF_MAP))
+ break;
+
+ /* Extract and buffer page key for data page (s390 only). */
+ page_key_memorize(buf + j);
+
+ if (pfn_valid(buf[j]) && memory_bm_pfn_present(bm, buf[j]))
+ memory_bm_set_bit(bm, buf[j]);
+ else
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_HIGHMEM
+/*
+ * struct highmem_pbe is used for creating the list of highmem pages that
+ * should be restored atomically during the resume from disk, because the page
+ * frames they have occupied before the suspend are in use.
+ */
+struct highmem_pbe {
+ struct page *copy_page; /* data is here now */
+ struct page *orig_page; /* data was here before the suspend */
+ struct highmem_pbe *next;
+};
+
+/*
+ * List of highmem PBEs needed for restoring the highmem 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 directly to their "original" page frames.
+ */
+static struct highmem_pbe *highmem_pblist;
+
+/**
+ * count_highmem_image_pages - Compute the number of highmem pages in the image.
+ * @bm: Memory bitmap.
+ *
+ * The bits in @bm that correspond to image pages are assumed to be set.
+ */
+static unsigned int count_highmem_image_pages(struct memory_bitmap *bm)
+{
+ unsigned long pfn;
+ unsigned int cnt = 0;
+
+ memory_bm_position_reset(bm);
+ pfn = memory_bm_next_pfn(bm);
+ while (pfn != BM_END_OF_MAP) {
+ if (PageHighMem(pfn_to_page(pfn)))
+ cnt++;
+
+ pfn = memory_bm_next_pfn(bm);
+ }
+ return cnt;
+}
+
+static unsigned int safe_highmem_pages;
+
+static struct memory_bitmap *safe_highmem_bm;
+
+/**
+ * prepare_highmem_image - Allocate memory for loading highmem data from image.
+ * @bm: Pointer to an uninitialized memory bitmap structure.
+ * @nr_highmem_p: Pointer to the number of highmem image pages.
+ *
+ * Try to allocate as many highmem pages as there are highmem image pages
+ * (@nr_highmem_p points to the variable containing the number of highmem image
+ * pages). The pages that are "safe" (ie. will not be overwritten when the
+ * hibernation image is restored entirely) have the corresponding bits set in
+ * @bm (it must be unitialized).
+ *
+ * NOTE: This function should not be called if there are no highmem image pages.
+ */
+static int prepare_highmem_image(struct memory_bitmap *bm,
+ unsigned int *nr_highmem_p)
+{
+ unsigned int to_alloc;
+
+ if (memory_bm_create(bm, GFP_ATOMIC, PG_SAFE))
+ return -ENOMEM;
+
+ if (get_highmem_buffer(PG_SAFE))
+ return -ENOMEM;
+
+ to_alloc = count_free_highmem_pages();
+ if (to_alloc > *nr_highmem_p)
+ to_alloc = *nr_highmem_p;
+ else
+ *nr_highmem_p = to_alloc;
+
+ safe_highmem_pages = 0;
+ while (to_alloc-- > 0) {
+ struct page *page;
+
+ page = alloc_page(__GFP_HIGHMEM);
+ if (!swsusp_page_is_free(page)) {
+ /* The page is "safe", set its bit the bitmap */
+ memory_bm_set_bit(bm, page_to_pfn(page));
+ safe_highmem_pages++;
+ }
+ /* Mark the page as allocated */
+ swsusp_set_page_forbidden(page);
+ swsusp_set_page_free(page);
+ }
+ memory_bm_position_reset(bm);
+ safe_highmem_bm = bm;
+ return 0;
+}
+
+static struct page *last_highmem_page;
+
+/**
+ * get_highmem_page_buffer - Prepare a buffer to store a highmem image page.
+ *
+ * For a given highmem image page get a buffer that suspend_write_next() should
+ * return to its caller to write to.
+ *
+ * If the page is to be saved to its "original" page frame or a copy of
+ * the page is to be made in the highmem, @buffer is returned. Otherwise,
+ * the copy of the page is to be made in normal memory, so the address of
+ * the copy is returned.
+ *
+ * If @buffer is returned, the caller of suspend_write_next() will write
+ * the page's contents to @buffer, so they will have to be copied to the
+ * right location on the next call to suspend_write_next() and it is done
+ * with the help of copy_last_highmem_page(). For this purpose, if
+ * @buffer is returned, @last_highmem_page is set to the page to which
+ * the data will have to be copied from @buffer.
+ */
+static void *get_highmem_page_buffer(struct page *page,
+ struct chain_allocator *ca)
+{
+ struct highmem_pbe *pbe;
+ void *kaddr;
+
+ if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) {
+ /*
+ * We have allocated the "original" page frame and we can
+ * use it directly to store the loaded page.
+ */
+ last_highmem_page = page;
+ return buffer;
+ }
+ /*
+ * The "original" page frame has not been allocated and we have to
+ * use a "safe" page frame to store the loaded page.
+ */
+ pbe = chain_alloc(ca, sizeof(struct highmem_pbe));
+ if (!pbe) {
+ swsusp_free();
+ return ERR_PTR(-ENOMEM);
+ }
+ pbe->orig_page = page;
+ if (safe_highmem_pages > 0) {
+ struct page *tmp;
+
+ /* Copy of the page will be stored in high memory */
+ kaddr = buffer;
+ tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm));
+ safe_highmem_pages--;
+ last_highmem_page = tmp;
+ pbe->copy_page = tmp;
+ } else {
+ /* Copy of the page will be stored in normal memory */
+ kaddr = safe_pages_list;
+ safe_pages_list = safe_pages_list->next;
+ pbe->copy_page = virt_to_page(kaddr);
+ }
+ pbe->next = highmem_pblist;
+ highmem_pblist = pbe;
+ return kaddr;
+}
+
+/**
+ * copy_last_highmem_page - Copy most the most recent highmem image page.
+ *
+ * Copy the contents of a highmem image from @buffer, where the caller of
+ * snapshot_write_next() has stored them, to the right location represented by
+ * @last_highmem_page .
+ */
+static void copy_last_highmem_page(void)
+{
+ if (last_highmem_page) {
+ void *dst;
+
+ dst = kmap_atomic(last_highmem_page);
+ copy_page(dst, buffer);
+ kunmap_atomic(dst);
+ last_highmem_page = NULL;
+ }
+}
+
+static inline int last_highmem_page_copied(void)
+{
+ return !last_highmem_page;
+}
+
+static inline void free_highmem_data(void)
+{
+ if (safe_highmem_bm)
+ memory_bm_free(safe_highmem_bm, PG_UNSAFE_CLEAR);
+
+ if (buffer)
+ free_image_page(buffer, PG_UNSAFE_CLEAR);
+}
+#else
+static unsigned int count_highmem_image_pages(struct memory_bitmap *bm) { return 0; }
+
+static inline int prepare_highmem_image(struct memory_bitmap *bm,
+ unsigned int *nr_highmem_p) { return 0; }
+
+static inline void *get_highmem_page_buffer(struct page *page,
+ struct chain_allocator *ca)
+{
+ return ERR_PTR(-EINVAL);
+}
+
+static inline void copy_last_highmem_page(void) {}
+static inline int last_highmem_page_copied(void) { return 1; }
+static inline void free_highmem_data(void) {}
+#endif /* CONFIG_HIGHMEM */
+
+#define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe))
+
+/**
+ * prepare_image - Make room for loading hibernation image.
+ * @new_bm: Unitialized memory bitmap structure.
+ * @bm: Memory bitmap with unsafe pages marked.
+ *
+ * Use @bm to mark the pages that will be overwritten in the process of
+ * restoring the system memory state from the suspend image ("unsafe" pages)
+ * and allocate memory for the image.
+ *
+ * The idea is to allocate a new memory bitmap first and then allocate
+ * as many pages as needed for image data, but without specifying what those
+ * pages will be used for just yet. Instead, we mark them all as allocated and
+ * create a lists of "safe" pages to be used later. On systems with high
+ * memory a list of "safe" highmem pages is created too.
+ */
+static int prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm)
+{
+ unsigned int nr_pages, nr_highmem;
+ struct linked_page *lp;
+ int error;
+
+ /* If there is no highmem, the buffer will not be necessary */
+ free_image_page(buffer, PG_UNSAFE_CLEAR);
+ buffer = NULL;
+
+ nr_highmem = count_highmem_image_pages(bm);
+ mark_unsafe_pages(bm);
+
+ error = memory_bm_create(new_bm, GFP_ATOMIC, PG_SAFE);
+ if (error)
+ goto Free;
+
+ duplicate_memory_bitmap(new_bm, bm);
+ memory_bm_free(bm, PG_UNSAFE_KEEP);
+ if (nr_highmem > 0) {
+ error = prepare_highmem_image(bm, &nr_highmem);
+ if (error)
+ goto Free;
+ }
+ /*
+ * Reserve some safe pages for potential later use.
+ *
+ * NOTE: This way we make sure there will be enough safe pages for the
+ * chain_alloc() in get_buffer(). It is a bit wasteful, but
+ * nr_copy_pages cannot be greater than 50% of the memory anyway.
+ *
+ * nr_copy_pages cannot be less than allocated_unsafe_pages too.
+ */
+ nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages;
+ nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE);
+ while (nr_pages > 0) {
+ lp = get_image_page(GFP_ATOMIC, PG_SAFE);
+ if (!lp) {
+ error = -ENOMEM;
+ goto Free;
+ }
+ lp->next = safe_pages_list;
+ safe_pages_list = lp;
+ nr_pages--;
+ }
+ /* Preallocate memory for the image */
+ nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages;
+ while (nr_pages > 0) {
+ lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC);
+ if (!lp) {
+ error = -ENOMEM;
+ goto Free;
+ }
+ if (!swsusp_page_is_free(virt_to_page(lp))) {
+ /* The page is "safe", add it to the list */
+ lp->next = safe_pages_list;
+ safe_pages_list = lp;
+ }
+ /* Mark the page as allocated */
+ swsusp_set_page_forbidden(virt_to_page(lp));
+ swsusp_set_page_free(virt_to_page(lp));
+ nr_pages--;
+ }
+ return 0;
+
+ Free:
+ swsusp_free();
+ return error;
+}
+
+/**
+ * get_buffer - Get the address to store the next image data page.
+ *
+ * Get the address that snapshot_write_next() should return to its caller to
+ * write to.
+ */
+static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
+{
+ struct pbe *pbe;
+ struct page *page;
+ unsigned long pfn = memory_bm_next_pfn(bm);
+
+ if (pfn == BM_END_OF_MAP)
+ return ERR_PTR(-EFAULT);
+
+ page = pfn_to_page(pfn);
+ if (PageHighMem(page))
+ return get_highmem_page_buffer(page, ca);
+
+ if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page))
+ /*
+ * We have allocated the "original" page frame and we can
+ * use it directly to store the loaded page.
+ */
+ return page_address(page);
+
+ /*
+ * The "original" page frame has not been allocated and we have to
+ * use a "safe" page frame to store the loaded page.
+ */
+ pbe = chain_alloc(ca, sizeof(struct pbe));
+ if (!pbe) {
+ swsusp_free();
+ return ERR_PTR(-ENOMEM);
+ }
+ pbe->orig_address = page_address(page);
+ pbe->address = safe_pages_list;
+ safe_pages_list = safe_pages_list->next;
+ pbe->next = restore_pblist;
+ restore_pblist = pbe;
+ return pbe->address;
+}
+
+/**
+ * snapshot_write_next - Get the address to store the next image page.
+ * @handle: Snapshot handle structure to guide the writing.
+ *
+ * On the first call, @handle should point to a zeroed snapshot_handle
+ * structure. The structure gets populated then and a pointer to it should be
+ * passed to this function every next time.
+ *
+ * On success, the function returns a positive number. Then, the caller
+ * is allowed to write up to the returned number of bytes to the memory
+ * location computed by the data_of() macro.
+ *
+ * The function returns 0 to indicate the "end of file" condition. Negative
+ * numbers are returned on errors, in which cases the structure pointed to by
+ * @handle is not updated and should not be used any more.
+ */
+int snapshot_write_next(struct snapshot_handle *handle)
+{
+ static struct chain_allocator ca;
+ int error = 0;
+
+ /* Check if we have already loaded the entire image */
+ if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages)
+ return 0;
+
+ handle->sync_read = 1;
+
+ if (!handle->cur) {
+ if (!buffer)
+ /* This makes the buffer be freed by swsusp_free() */
+ buffer = get_image_page(GFP_ATOMIC, PG_ANY);
+
+ if (!buffer)
+ return -ENOMEM;
+
+ handle->buffer = buffer;
+ } else if (handle->cur == 1) {
+ error = load_header(buffer);
+ if (error)
+ return error;
+
+ safe_pages_list = NULL;
+
+ error = memory_bm_create(©_bm, GFP_ATOMIC, PG_ANY);
+ if (error)
+ return error;
+
+ /* Allocate buffer for page keys. */
+ error = page_key_alloc(nr_copy_pages);
+ if (error)
+ return error;
+
+ hibernate_restore_protection_begin();
+ } else if (handle->cur <= nr_meta_pages + 1) {
+ error = unpack_orig_pfns(buffer, ©_bm);
+ if (error)
+ return error;
+
+ if (handle->cur == nr_meta_pages + 1) {
+ error = prepare_image(&orig_bm, ©_bm);
+ if (error)
+ return error;
+
+ chain_init(&ca, GFP_ATOMIC, PG_SAFE);
+ memory_bm_position_reset(&orig_bm);
+ restore_pblist = NULL;
+ handle->buffer = get_buffer(&orig_bm, &ca);
+ handle->sync_read = 0;
+ if (IS_ERR(handle->buffer))
+ return PTR_ERR(handle->buffer);
+ }
+ } else {
+ copy_last_highmem_page();
+ /* Restore page key for data page (s390 only). */
+ page_key_write(handle->buffer);
+ hibernate_restore_protect_page(handle->buffer);
+ handle->buffer = get_buffer(&orig_bm, &ca);
+ if (IS_ERR(handle->buffer))
+ return PTR_ERR(handle->buffer);
+ if (handle->buffer != buffer)
+ handle->sync_read = 0;
+ }
+ handle->cur++;
+ return PAGE_SIZE;
+}
+
+/**
+ * snapshot_write_finalize - Complete the loading of a hibernation image.
+ *
+ * Must be called after the last call to snapshot_write_next() in case the last
+ * page in the image happens to be a highmem page and its contents should be
+ * stored in highmem. Additionally, it recycles bitmap memory that's not
+ * necessary any more.
+ */
+void snapshot_write_finalize(struct snapshot_handle *handle)
+{
+ copy_last_highmem_page();
+ /* Restore page key for data page (s390 only). */
+ page_key_write(handle->buffer);
+ page_key_free();
+ hibernate_restore_protect_page(handle->buffer);
+ /* Do that only if we have loaded the image entirely */
+ if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages) {
+ memory_bm_recycle(&orig_bm);
+ free_highmem_data();
+ }
+}
+
+int snapshot_image_loaded(struct snapshot_handle *handle)
+{
+ return !(!nr_copy_pages || !last_highmem_page_copied() ||
+ handle->cur <= nr_meta_pages + nr_copy_pages);
+}
+
+#ifdef CONFIG_HIGHMEM
+/* Assumes that @buf is ready and points to a "safe" page */
+static inline void swap_two_pages_data(struct page *p1, struct page *p2,
+ void *buf)
+{
+ void *kaddr1, *kaddr2;
+
+ kaddr1 = kmap_atomic(p1);
+ kaddr2 = kmap_atomic(p2);
+ copy_page(buf, kaddr1);
+ copy_page(kaddr1, kaddr2);
+ copy_page(kaddr2, buf);
+ kunmap_atomic(kaddr2);
+ kunmap_atomic(kaddr1);
+}
+
+/**
+ * restore_highmem - Put highmem image pages into their original locations.
+ *
+ * For each highmem page that was in use before hibernation and is included in
+ * the image, and also has been allocated by the "restore" kernel, swap its
+ * current contents with the previous (ie. "before hibernation") ones.
+ *
+ * If the restore eventually fails, we can call this function once again and
+ * restore the highmem state as seen by the restore kernel.
+ */
+int restore_highmem(void)
+{
+ struct highmem_pbe *pbe = highmem_pblist;
+ void *buf;
+
+ if (!pbe)
+ return 0;
+
+ buf = get_image_page(GFP_ATOMIC, PG_SAFE);
+ if (!buf)
+ return -ENOMEM;
+
+ while (pbe) {
+ swap_two_pages_data(pbe->copy_page, pbe->orig_page, buf);
+ pbe = pbe->next;
+ }
+ free_image_page(buf, PG_UNSAFE_CLEAR);
+ return 0;
+}
+#endif /* CONFIG_HIGHMEM */
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
new file mode 100644
index 0000000..0bd595a
--- /dev/null
+++ b/kernel/power/suspend.c
@@ -0,0 +1,628 @@
+/*
+ * 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.
+ */
+
+#define pr_fmt(fmt) "PM: " fmt
+
+#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/cpuidle.h>
+#include <linux/syscalls.h>
+#include <linux/gfp.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/suspend.h>
+#include <linux/syscore_ops.h>
+#include <linux/swait.h>
+#include <linux/ftrace.h>
+#include <trace/events/power.h>
+#include <linux/compiler.h>
+#include <linux/moduleparam.h>
+
+#include "power.h"
+
+const char * const pm_labels[] = {
+ [PM_SUSPEND_TO_IDLE] = "freeze",
+ [PM_SUSPEND_STANDBY] = "standby",
+ [PM_SUSPEND_MEM] = "mem",
+};
+const char *pm_states[PM_SUSPEND_MAX];
+static const char * const mem_sleep_labels[] = {
+ [PM_SUSPEND_TO_IDLE] = "s2idle",
+ [PM_SUSPEND_STANDBY] = "shallow",
+ [PM_SUSPEND_MEM] = "deep",
+};
+const char *mem_sleep_states[PM_SUSPEND_MAX];
+
+suspend_state_t mem_sleep_current = PM_SUSPEND_TO_IDLE;
+suspend_state_t mem_sleep_default = PM_SUSPEND_MAX;
+suspend_state_t pm_suspend_target_state;
+EXPORT_SYMBOL_GPL(pm_suspend_target_state);
+
+unsigned int pm_suspend_global_flags;
+EXPORT_SYMBOL_GPL(pm_suspend_global_flags);
+
+static const struct platform_suspend_ops *suspend_ops;
+static const struct platform_s2idle_ops *s2idle_ops;
+static DECLARE_SWAIT_QUEUE_HEAD(s2idle_wait_head);
+
+enum s2idle_states __read_mostly s2idle_state;
+static DEFINE_RAW_SPINLOCK(s2idle_lock);
+
+bool pm_suspend_via_s2idle(void)
+{
+ return mem_sleep_current == PM_SUSPEND_TO_IDLE;
+}
+EXPORT_SYMBOL_GPL(pm_suspend_via_s2idle);
+
+void s2idle_set_ops(const struct platform_s2idle_ops *ops)
+{
+ lock_system_sleep();
+ s2idle_ops = ops;
+ unlock_system_sleep();
+}
+
+static void s2idle_begin(void)
+{
+ s2idle_state = S2IDLE_STATE_NONE;
+}
+
+static void s2idle_enter(void)
+{
+ trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, true);
+
+ raw_spin_lock_irq(&s2idle_lock);
+ if (pm_wakeup_pending())
+ goto out;
+
+ s2idle_state = S2IDLE_STATE_ENTER;
+ raw_spin_unlock_irq(&s2idle_lock);
+
+ get_online_cpus();
+ cpuidle_resume();
+
+ /* Push all the CPUs into the idle loop. */
+ wake_up_all_idle_cpus();
+ /* Make the current CPU wait so it can enter the idle loop too. */
+ swait_event_exclusive(s2idle_wait_head,
+ s2idle_state == S2IDLE_STATE_WAKE);
+
+ cpuidle_pause();
+ put_online_cpus();
+
+ raw_spin_lock_irq(&s2idle_lock);
+
+ out:
+ s2idle_state = S2IDLE_STATE_NONE;
+ raw_spin_unlock_irq(&s2idle_lock);
+
+ trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, false);
+}
+
+static void s2idle_loop(void)
+{
+ pm_pr_dbg("suspend-to-idle\n");
+
+ for (;;) {
+ int error;
+
+ dpm_noirq_begin();
+
+ /*
+ * Suspend-to-idle equals
+ * frozen processes + suspended devices + idle processors.
+ * Thus s2idle_enter() should be called right after
+ * all devices have been suspended.
+ *
+ * Wakeups during the noirq suspend of devices may be spurious,
+ * so prevent them from terminating the loop right away.
+ */
+ error = dpm_noirq_suspend_devices(PMSG_SUSPEND);
+ if (!error)
+ s2idle_enter();
+ else if (error == -EBUSY && pm_wakeup_pending())
+ error = 0;
+
+ if (!error && s2idle_ops && s2idle_ops->wake)
+ s2idle_ops->wake();
+
+ dpm_noirq_resume_devices(PMSG_RESUME);
+
+ dpm_noirq_end();
+
+ if (error)
+ break;
+
+ if (s2idle_ops && s2idle_ops->sync)
+ s2idle_ops->sync();
+
+ if (pm_wakeup_pending())
+ break;
+
+ pm_wakeup_clear(false);
+ }
+
+ pm_pr_dbg("resume from suspend-to-idle\n");
+}
+
+void s2idle_wake(void)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&s2idle_lock, flags);
+ if (s2idle_state > S2IDLE_STATE_NONE) {
+ s2idle_state = S2IDLE_STATE_WAKE;
+ swake_up_one(&s2idle_wait_head);
+ }
+ raw_spin_unlock_irqrestore(&s2idle_lock, flags);
+}
+EXPORT_SYMBOL_GPL(s2idle_wake);
+
+static bool valid_state(suspend_state_t state)
+{
+ /*
+ * PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
+ * support and need to be valid to the low level
+ * implementation, no valid callback implies that none are valid.
+ */
+ return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
+}
+
+void __init pm_states_init(void)
+{
+ /* "mem" and "freeze" are always present in /sys/power/state. */
+ pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM];
+ pm_states[PM_SUSPEND_TO_IDLE] = pm_labels[PM_SUSPEND_TO_IDLE];
+ /*
+ * Suspend-to-idle should be supported even without any suspend_ops,
+ * initialize mem_sleep_states[] accordingly here.
+ */
+ mem_sleep_states[PM_SUSPEND_TO_IDLE] = mem_sleep_labels[PM_SUSPEND_TO_IDLE];
+}
+
+static int __init mem_sleep_default_setup(char *str)
+{
+ suspend_state_t state;
+
+ for (state = PM_SUSPEND_TO_IDLE; state <= PM_SUSPEND_MEM; state++)
+ if (mem_sleep_labels[state] &&
+ !strcmp(str, mem_sleep_labels[state])) {
+ mem_sleep_default = state;
+ break;
+ }
+
+ return 1;
+}
+__setup("mem_sleep_default=", mem_sleep_default_setup);
+
+/**
+ * suspend_set_ops - Set the global suspend method table.
+ * @ops: Suspend operations to use.
+ */
+void suspend_set_ops(const struct platform_suspend_ops *ops)
+{
+ lock_system_sleep();
+
+ suspend_ops = ops;
+
+ if (valid_state(PM_SUSPEND_STANDBY)) {
+ mem_sleep_states[PM_SUSPEND_STANDBY] = mem_sleep_labels[PM_SUSPEND_STANDBY];
+ pm_states[PM_SUSPEND_STANDBY] = pm_labels[PM_SUSPEND_STANDBY];
+ if (mem_sleep_default == PM_SUSPEND_STANDBY)
+ mem_sleep_current = PM_SUSPEND_STANDBY;
+ }
+ if (valid_state(PM_SUSPEND_MEM)) {
+ mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM];
+ if (mem_sleep_default >= PM_SUSPEND_MEM)
+ mem_sleep_current = PM_SUSPEND_MEM;
+ }
+
+ unlock_system_sleep();
+}
+EXPORT_SYMBOL_GPL(suspend_set_ops);
+
+/**
+ * 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;
+}
+EXPORT_SYMBOL_GPL(suspend_valid_only_mem);
+
+static bool sleep_state_supported(suspend_state_t state)
+{
+ return state == PM_SUSPEND_TO_IDLE || (suspend_ops && suspend_ops->enter);
+}
+
+static int platform_suspend_prepare(suspend_state_t state)
+{
+ return state != PM_SUSPEND_TO_IDLE && suspend_ops->prepare ?
+ suspend_ops->prepare() : 0;
+}
+
+static int platform_suspend_prepare_late(suspend_state_t state)
+{
+ return state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->prepare ?
+ s2idle_ops->prepare() : 0;
+}
+
+static int platform_suspend_prepare_noirq(suspend_state_t state)
+{
+ return state != PM_SUSPEND_TO_IDLE && suspend_ops->prepare_late ?
+ suspend_ops->prepare_late() : 0;
+}
+
+static void platform_resume_noirq(suspend_state_t state)
+{
+ if (state != PM_SUSPEND_TO_IDLE && suspend_ops->wake)
+ suspend_ops->wake();
+}
+
+static void platform_resume_early(suspend_state_t state)
+{
+ if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->restore)
+ s2idle_ops->restore();
+}
+
+static void platform_resume_finish(suspend_state_t state)
+{
+ if (state != PM_SUSPEND_TO_IDLE && suspend_ops->finish)
+ suspend_ops->finish();
+}
+
+static int platform_suspend_begin(suspend_state_t state)
+{
+ if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->begin)
+ return s2idle_ops->begin();
+ else if (suspend_ops && suspend_ops->begin)
+ return suspend_ops->begin(state);
+ else
+ return 0;
+}
+
+static void platform_resume_end(suspend_state_t state)
+{
+ if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->end)
+ s2idle_ops->end();
+ else if (suspend_ops && suspend_ops->end)
+ suspend_ops->end();
+}
+
+static void platform_recover(suspend_state_t state)
+{
+ if (state != PM_SUSPEND_TO_IDLE && suspend_ops->recover)
+ suspend_ops->recover();
+}
+
+static bool platform_suspend_again(suspend_state_t state)
+{
+ return state != PM_SUSPEND_TO_IDLE && suspend_ops->suspend_again ?
+ suspend_ops->suspend_again() : false;
+}
+
+#ifdef CONFIG_PM_DEBUG
+static unsigned int pm_test_delay = 5;
+module_param(pm_test_delay, uint, 0644);
+MODULE_PARM_DESC(pm_test_delay,
+ "Number of seconds to wait before resuming from suspend test");
+#endif
+
+static int suspend_test(int level)
+{
+#ifdef CONFIG_PM_DEBUG
+ if (pm_test_level == level) {
+ pr_info("suspend debug: Waiting for %d second(s).\n",
+ pm_test_delay);
+ mdelay(pm_test_delay * 1000);
+ return 1;
+ }
+#endif /* !CONFIG_PM_DEBUG */
+ return 0;
+}
+
+/**
+ * suspend_prepare - Prepare for entering system sleep state.
+ *
+ * Common code run for every system sleep state that can be entered (except for
+ * hibernation). Run suspend notifiers, allocate the "suspend" console and
+ * freeze processes.
+ */
+static int suspend_prepare(suspend_state_t state)
+{
+ int error, nr_calls = 0;
+
+ if (!sleep_state_supported(state))
+ return -EPERM;
+
+ pm_prepare_console();
+
+ error = __pm_notifier_call_chain(PM_SUSPEND_PREPARE, -1, &nr_calls);
+ if (error) {
+ nr_calls--;
+ goto Finish;
+ }
+
+ trace_suspend_resume(TPS("freeze_processes"), 0, true);
+ error = suspend_freeze_processes();
+ trace_suspend_resume(TPS("freeze_processes"), 0, false);
+ if (!error)
+ return 0;
+
+ suspend_stats.failed_freeze++;
+ dpm_save_failed_step(SUSPEND_FREEZE);
+ Finish:
+ __pm_notifier_call_chain(PM_POST_SUSPEND, nr_calls, NULL);
+ pm_restore_console();
+ return error;
+}
+
+/* default implementation */
+void __weak arch_suspend_disable_irqs(void)
+{
+ local_irq_disable();
+}
+
+/* default implementation */
+void __weak arch_suspend_enable_irqs(void)
+{
+ local_irq_enable();
+}
+
+/**
+ * suspend_enter - Make the system enter the given sleep state.
+ * @state: System sleep state to enter.
+ * @wakeup: Returns information that the sleep state should not be re-entered.
+ *
+ * This function should be called after devices have been suspended.
+ */
+static int suspend_enter(suspend_state_t state, bool *wakeup)
+{
+ int error;
+
+ error = platform_suspend_prepare(state);
+ if (error)
+ goto Platform_finish;
+
+ error = dpm_suspend_late(PMSG_SUSPEND);
+ if (error) {
+ pr_err("late suspend of devices failed\n");
+ goto Platform_finish;
+ }
+ error = platform_suspend_prepare_late(state);
+ if (error)
+ goto Devices_early_resume;
+
+ if (state == PM_SUSPEND_TO_IDLE && pm_test_level != TEST_PLATFORM) {
+ s2idle_loop();
+ goto Platform_early_resume;
+ }
+
+ error = dpm_suspend_noirq(PMSG_SUSPEND);
+ if (error) {
+ pr_err("noirq suspend of devices failed\n");
+ goto Platform_early_resume;
+ }
+ error = platform_suspend_prepare_noirq(state);
+ if (error)
+ goto Platform_wake;
+
+ 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());
+
+ system_state = SYSTEM_SUSPEND;
+
+ error = syscore_suspend();
+ if (!error) {
+ *wakeup = pm_wakeup_pending();
+ if (!(suspend_test(TEST_CORE) || *wakeup)) {
+ trace_suspend_resume(TPS("machine_suspend"),
+ state, true);
+ error = suspend_ops->enter(state);
+ trace_suspend_resume(TPS("machine_suspend"),
+ state, false);
+ } else if (*wakeup) {
+ error = -EBUSY;
+ }
+ syscore_resume();
+ }
+
+ system_state = SYSTEM_RUNNING;
+
+ arch_suspend_enable_irqs();
+ BUG_ON(irqs_disabled());
+
+ Enable_cpus:
+ enable_nonboot_cpus();
+
+ Platform_wake:
+ platform_resume_noirq(state);
+ dpm_resume_noirq(PMSG_RESUME);
+
+ Platform_early_resume:
+ platform_resume_early(state);
+
+ Devices_early_resume:
+ dpm_resume_early(PMSG_RESUME);
+
+ Platform_finish:
+ platform_resume_finish(state);
+ return error;
+}
+
+/**
+ * suspend_devices_and_enter - Suspend devices and enter system sleep state.
+ * @state: System sleep state to enter.
+ */
+int suspend_devices_and_enter(suspend_state_t state)
+{
+ int error;
+ bool wakeup = false;
+
+ if (!sleep_state_supported(state))
+ return -ENOSYS;
+
+ pm_suspend_target_state = state;
+
+ error = platform_suspend_begin(state);
+ if (error)
+ goto Close;
+
+ suspend_console();
+ suspend_test_start();
+ error = dpm_suspend_start(PMSG_SUSPEND);
+ if (error) {
+ pr_err("Some devices failed to suspend, or early wake event detected\n");
+ goto Recover_platform;
+ }
+ suspend_test_finish("suspend devices");
+ if (suspend_test(TEST_DEVICES))
+ goto Recover_platform;
+
+ do {
+ error = suspend_enter(state, &wakeup);
+ } while (!error && !wakeup && platform_suspend_again(state));
+
+ Resume_devices:
+ suspend_test_start();
+ dpm_resume_end(PMSG_RESUME);
+ suspend_test_finish("resume devices");
+ trace_suspend_resume(TPS("resume_console"), state, true);
+ resume_console();
+ trace_suspend_resume(TPS("resume_console"), state, false);
+
+ Close:
+ platform_resume_end(state);
+ pm_suspend_target_state = PM_SUSPEND_ON;
+ return error;
+
+ Recover_platform:
+ platform_recover(state);
+ goto Resume_devices;
+}
+
+/**
+ * suspend_finish - Clean up before finishing the suspend sequence.
+ *
+ * Call platform code to clean up, restart processes, and free the console that
+ * we've allocated. This routine is not called for hibernation.
+ */
+static void suspend_finish(void)
+{
+ suspend_thaw_processes();
+ pm_notifier_call_chain(PM_POST_SUSPEND);
+ pm_restore_console();
+}
+
+/**
+ * enter_state - Do common work needed to enter system sleep state.
+ * @state: System sleep state to enter.
+ *
+ * Make sure that no one else is trying to put the system into a sleep state.
+ * Fail if that's not the case. Otherwise, prepare for system suspend, make the
+ * system enter the given sleep state and clean up after wakeup.
+ */
+static int enter_state(suspend_state_t state)
+{
+ int error;
+
+ trace_suspend_resume(TPS("suspend_enter"), state, true);
+ if (state == PM_SUSPEND_TO_IDLE) {
+#ifdef CONFIG_PM_DEBUG
+ if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
+ pr_warn("Unsupported test mode for suspend to idle, please choose none/freezer/devices/platform.\n");
+ return -EAGAIN;
+ }
+#endif
+ } else if (!valid_state(state)) {
+ return -EINVAL;
+ }
+ if (!mutex_trylock(&system_transition_mutex))
+ return -EBUSY;
+
+ if (state == PM_SUSPEND_TO_IDLE)
+ s2idle_begin();
+
+#ifndef CONFIG_SUSPEND_SKIP_SYNC
+ trace_suspend_resume(TPS("sync_filesystems"), 0, true);
+ pr_info("Syncing filesystems ... ");
+ ksys_sync();
+ pr_cont("done.\n");
+ trace_suspend_resume(TPS("sync_filesystems"), 0, false);
+#endif
+
+ pm_pr_dbg("Preparing system for sleep (%s)\n", mem_sleep_labels[state]);
+ pm_suspend_clear_flags();
+ error = suspend_prepare(state);
+ if (error)
+ goto Unlock;
+
+ if (suspend_test(TEST_FREEZER))
+ goto Finish;
+
+ trace_suspend_resume(TPS("suspend_enter"), state, false);
+ pm_pr_dbg("Suspending system (%s)\n", mem_sleep_labels[state]);
+ pm_restrict_gfp_mask();
+ error = suspend_devices_and_enter(state);
+ pm_restore_gfp_mask();
+
+ Finish:
+ events_check_enabled = false;
+ pm_pr_dbg("Finishing wakeup.\n");
+ suspend_finish();
+ Unlock:
+ mutex_unlock(&system_transition_mutex);
+ return error;
+}
+
+/**
+ * pm_suspend - Externally visible function for suspending the system.
+ * @state: System sleep state to enter.
+ *
+ * Check if the value of @state represents one of the supported states,
+ * execute enter_state() and update system suspend statistics.
+ */
+int pm_suspend(suspend_state_t state)
+{
+ int error;
+
+ if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX)
+ return -EINVAL;
+
+ pr_info("suspend entry (%s)\n", mem_sleep_labels[state]);
+ error = enter_state(state);
+ if (error) {
+ suspend_stats.fail++;
+ dpm_save_failed_errno(error);
+ } else {
+ suspend_stats.success++;
+ }
+ pr_info("suspend exit\n");
+ return error;
+}
+EXPORT_SYMBOL(pm_suspend);
diff --git a/kernel/power/suspend_test.c b/kernel/power/suspend_test.c
new file mode 100644
index 0000000..6a897e8
--- /dev/null
+++ b/kernel/power/suspend_test.c
@@ -0,0 +1,220 @@
+/*
+ * 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 10
+
+static unsigned long suspend_test_start_time;
+static u32 test_repeat_count_max = 1;
+static u32 test_repeat_count_current;
+
+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, time: %u\n", label, msec);
+}
+
+/*
+ * 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 */
+repeat:
+ 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)
+ state = PM_SUSPEND_TO_IDLE;
+ }
+ if (state == PM_SUSPEND_TO_IDLE) {
+ printk(info_test, pm_states[state]);
+ status = pm_suspend(state);
+ }
+
+ if (status < 0)
+ printk(err_suspend, status);
+
+ test_repeat_count_current++;
+ if (test_repeat_count_current < test_repeat_count_max)
+ goto repeat;
+
+ /* 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, const void *data)
+{
+ struct rtc_device *candidate = to_rtc_device(dev);
+
+ if (!candidate->ops->set_alarm)
+ return 0;
+ if (!device_may_wakeup(candidate->dev.parent))
+ return 0;
+
+ 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 const char *test_state_label __initdata;
+
+static char warn_bad_state[] __initdata =
+ KERN_WARNING "PM: can't test '%s' suspend state\n";
+
+static int __init setup_test_suspend(char *value)
+{
+ int i;
+ char *repeat;
+ char *suspend_type;
+
+ /* example : "=mem[,N]" ==> "mem[,N]" */
+ value++;
+ suspend_type = strsep(&value, ",");
+ if (!suspend_type)
+ return 0;
+
+ repeat = strsep(&value, ",");
+ if (repeat) {
+ if (kstrtou32(repeat, 0, &test_repeat_count_max))
+ return 0;
+ }
+
+ for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
+ if (!strcmp(pm_labels[i], suspend_type)) {
+ test_state_label = pm_labels[i];
+ return 0;
+ }
+
+ printk(warn_bad_state, suspend_type);
+ 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";
+
+ struct rtc_device *rtc = NULL;
+ struct device *dev;
+ suspend_state_t test_state;
+
+ /* PM is initialized by now; is that state testable? */
+ if (!test_state_label)
+ return 0;
+
+ for (test_state = PM_SUSPEND_MIN; test_state < PM_SUSPEND_MAX; test_state++) {
+ const char *state_label = pm_states[test_state];
+
+ if (state_label && !strcmp(test_state_label, state_label))
+ break;
+ }
+ if (test_state == PM_SUSPEND_MAX) {
+ printk(warn_bad_state, test_state_label);
+ return 0;
+ }
+
+ /* RTCs have initialized by now too ... can we use one? */
+ dev = class_find_device(rtc_class, NULL, NULL, has_wakealarm);
+ if (dev) {
+ rtc = rtc_class_open(dev_name(dev));
+ put_device(dev);
+ }
+ if (!rtc) {
+ printk(warn_no_rtc);
+ return 0;
+ }
+
+ /* go for it */
+ test_wakealarm(rtc, test_state);
+ rtc_class_close(rtc);
+ return 0;
+}
+late_initcall(test_suspend);
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
new file mode 100644
index 0000000..d7f6c1a
--- /dev/null
+++ b/kernel/power/swap.c
@@ -0,0 +1,1604 @@
+/*
+ * linux/kernel/power/swap.c
+ *
+ * This file provides functions for reading the suspend image from
+ * and writing it to a swap partition.
+ *
+ * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz>
+ * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
+ * Copyright (C) 2010-2012 Bojan Smojver <bojan@rexursive.com>
+ *
+ * This file is released under the GPLv2.
+ *
+ */
+
+#define pr_fmt(fmt) "PM: " fmt
+
+#include <linux/module.h>
+#include <linux/file.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/genhd.h>
+#include <linux/device.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
+#include <linux/pm.h>
+#include <linux/slab.h>
+#include <linux/lzo.h>
+#include <linux/vmalloc.h>
+#include <linux/cpumask.h>
+#include <linux/atomic.h>
+#include <linux/kthread.h>
+#include <linux/crc32.h>
+#include <linux/ktime.h>
+
+#include "power.h"
+
+#define HIBERNATE_SIG "S1SUSPEND"
+
+/*
+ * When reading an {un,}compressed image, we may restore pages in place,
+ * in which case some architectures need these pages cleaning before they
+ * can be executed. We don't know which pages these may be, so clean the lot.
+ */
+static bool clean_pages_on_read;
+static bool clean_pages_on_decompress;
+
+/*
+ * The swap map is a data structure used for keeping track of each page
+ * written to a swap partition. It consists of many swap_map_page
+ * structures that contain each an array of MAP_PAGE_ENTRIES swap entries.
+ * These structures are stored on the swap and linked together with the
+ * help of the .next_swap member.
+ *
+ * The swap map is created during suspend. The swap map pages are
+ * allocated and populated one at a time, so we only need one memory
+ * page to set up the entire structure.
+ *
+ * During resume we pick up all swap_map_page structures into a list.
+ */
+
+#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
+
+/*
+ * Number of free pages that are not high.
+ */
+static inline unsigned long low_free_pages(void)
+{
+ return nr_free_pages() - nr_free_highpages();
+}
+
+/*
+ * Number of pages required to be kept free while writing the image. Always
+ * half of all available low pages before the writing starts.
+ */
+static inline unsigned long reqd_free_pages(void)
+{
+ return low_free_pages() / 2;
+}
+
+struct swap_map_page {
+ sector_t entries[MAP_PAGE_ENTRIES];
+ sector_t next_swap;
+};
+
+struct swap_map_page_list {
+ struct swap_map_page *map;
+ struct swap_map_page_list *next;
+};
+
+/**
+ * The swap_map_handle structure is used for handling swap in
+ * a file-alike way
+ */
+
+struct swap_map_handle {
+ struct swap_map_page *cur;
+ struct swap_map_page_list *maps;
+ sector_t cur_swap;
+ sector_t first_sector;
+ unsigned int k;
+ unsigned long reqd_free_pages;
+ u32 crc32;
+};
+
+struct swsusp_header {
+ char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) -
+ sizeof(u32)];
+ u32 crc32;
+ sector_t image;
+ unsigned int flags; /* Flags to pass to the "boot" kernel */
+ char orig_sig[10];
+ char sig[10];
+} __packed;
+
+static struct swsusp_header *swsusp_header;
+
+/**
+ * The following functions are used for tracing the allocated
+ * swap pages, so that they can be freed in case of an error.
+ */
+
+struct swsusp_extent {
+ struct rb_node node;
+ unsigned long start;
+ unsigned long end;
+};
+
+static struct rb_root swsusp_extents = RB_ROOT;
+
+static int swsusp_extents_insert(unsigned long swap_offset)
+{
+ struct rb_node **new = &(swsusp_extents.rb_node);
+ struct rb_node *parent = NULL;
+ struct swsusp_extent *ext;
+
+ /* Figure out where to put the new node */
+ while (*new) {
+ ext = rb_entry(*new, struct swsusp_extent, node);
+ parent = *new;
+ if (swap_offset < ext->start) {
+ /* Try to merge */
+ if (swap_offset == ext->start - 1) {
+ ext->start--;
+ return 0;
+ }
+ new = &((*new)->rb_left);
+ } else if (swap_offset > ext->end) {
+ /* Try to merge */
+ if (swap_offset == ext->end + 1) {
+ ext->end++;
+ return 0;
+ }
+ new = &((*new)->rb_right);
+ } else {
+ /* It already is in the tree */
+ return -EINVAL;
+ }
+ }
+ /* Add the new node and rebalance the tree. */
+ ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
+ if (!ext)
+ return -ENOMEM;
+
+ ext->start = swap_offset;
+ ext->end = swap_offset;
+ rb_link_node(&ext->node, parent, new);
+ rb_insert_color(&ext->node, &swsusp_extents);
+ return 0;
+}
+
+/**
+ * alloc_swapdev_block - allocate a swap page and register that it has
+ * been allocated, so that it can be freed in case of an error.
+ */
+
+sector_t alloc_swapdev_block(int swap)
+{
+ unsigned long offset;
+
+ offset = swp_offset(get_swap_page_of_type(swap));
+ if (offset) {
+ if (swsusp_extents_insert(offset))
+ swap_free(swp_entry(swap, offset));
+ else
+ return swapdev_block(swap, offset);
+ }
+ return 0;
+}
+
+/**
+ * free_all_swap_pages - free swap pages allocated for saving image data.
+ * It also frees the extents used to register which swap entries had been
+ * allocated.
+ */
+
+void free_all_swap_pages(int swap)
+{
+ struct rb_node *node;
+
+ while ((node = swsusp_extents.rb_node)) {
+ struct swsusp_extent *ext;
+ unsigned long offset;
+
+ ext = rb_entry(node, struct swsusp_extent, node);
+ rb_erase(node, &swsusp_extents);
+ for (offset = ext->start; offset <= ext->end; offset++)
+ swap_free(swp_entry(swap, offset));
+
+ kfree(ext);
+ }
+}
+
+int swsusp_swap_in_use(void)
+{
+ return (swsusp_extents.rb_node != NULL);
+}
+
+/*
+ * General things
+ */
+
+static unsigned short root_swap = 0xffff;
+static struct block_device *hib_resume_bdev;
+
+struct hib_bio_batch {
+ atomic_t count;
+ wait_queue_head_t wait;
+ blk_status_t error;
+};
+
+static void hib_init_batch(struct hib_bio_batch *hb)
+{
+ atomic_set(&hb->count, 0);
+ init_waitqueue_head(&hb->wait);
+ hb->error = BLK_STS_OK;
+}
+
+static void hib_end_io(struct bio *bio)
+{
+ struct hib_bio_batch *hb = bio->bi_private;
+ struct page *page = bio_first_page_all(bio);
+
+ if (bio->bi_status) {
+ pr_alert("Read-error on swap-device (%u:%u:%Lu)\n",
+ MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
+ (unsigned long long)bio->bi_iter.bi_sector);
+ }
+
+ if (bio_data_dir(bio) == WRITE)
+ put_page(page);
+ else if (clean_pages_on_read)
+ flush_icache_range((unsigned long)page_address(page),
+ (unsigned long)page_address(page) + PAGE_SIZE);
+
+ if (bio->bi_status && !hb->error)
+ hb->error = bio->bi_status;
+ if (atomic_dec_and_test(&hb->count))
+ wake_up(&hb->wait);
+
+ bio_put(bio);
+}
+
+static int hib_submit_io(int op, int op_flags, pgoff_t page_off, void *addr,
+ struct hib_bio_batch *hb)
+{
+ struct page *page = virt_to_page(addr);
+ struct bio *bio;
+ int error = 0;
+
+ bio = bio_alloc(GFP_NOIO | __GFP_HIGH, 1);
+ bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
+ bio_set_dev(bio, hib_resume_bdev);
+ bio_set_op_attrs(bio, op, op_flags);
+
+ if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+ pr_err("Adding page to bio failed at %llu\n",
+ (unsigned long long)bio->bi_iter.bi_sector);
+ bio_put(bio);
+ return -EFAULT;
+ }
+
+ if (hb) {
+ bio->bi_end_io = hib_end_io;
+ bio->bi_private = hb;
+ atomic_inc(&hb->count);
+ submit_bio(bio);
+ } else {
+ error = submit_bio_wait(bio);
+ bio_put(bio);
+ }
+
+ return error;
+}
+
+static blk_status_t hib_wait_io(struct hib_bio_batch *hb)
+{
+ wait_event(hb->wait, atomic_read(&hb->count) == 0);
+ return blk_status_to_errno(hb->error);
+}
+
+/*
+ * Saving part
+ */
+
+static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
+{
+ int error;
+
+ hib_submit_io(REQ_OP_READ, 0, swsusp_resume_block,
+ swsusp_header, NULL);
+ if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
+ !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
+ memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
+ memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
+ swsusp_header->image = handle->first_sector;
+ swsusp_header->flags = flags;
+ if (flags & SF_CRC32_MODE)
+ swsusp_header->crc32 = handle->crc32;
+ error = hib_submit_io(REQ_OP_WRITE, REQ_SYNC,
+ swsusp_resume_block, swsusp_header, NULL);
+ } else {
+ pr_err("Swap header not found!\n");
+ error = -ENODEV;
+ }
+ return error;
+}
+
+/**
+ * swsusp_swap_check - check if the resume device is a swap device
+ * and get its index (if so)
+ *
+ * This is called before saving image
+ */
+static int swsusp_swap_check(void)
+{
+ int res;
+
+ res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
+ &hib_resume_bdev);
+ if (res < 0)
+ return res;
+
+ root_swap = res;
+ res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL);
+ if (res)
+ return res;
+
+ res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
+ if (res < 0)
+ blkdev_put(hib_resume_bdev, FMODE_WRITE);
+
+ /*
+ * Update the resume device to the one actually used,
+ * so the test_resume mode can use it in case it is
+ * invoked from hibernate() to test the snapshot.
+ */
+ swsusp_resume_device = hib_resume_bdev->bd_dev;
+ return res;
+}
+
+/**
+ * write_page - Write one page to given swap location.
+ * @buf: Address we're writing.
+ * @offset: Offset of the swap page we're writing to.
+ * @hb: bio completion batch
+ */
+
+static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb)
+{
+ void *src;
+ int ret;
+
+ if (!offset)
+ return -ENOSPC;
+
+ if (hb) {
+ src = (void *)__get_free_page(GFP_NOIO | __GFP_NOWARN |
+ __GFP_NORETRY);
+ if (src) {
+ copy_page(src, buf);
+ } else {
+ ret = hib_wait_io(hb); /* Free pages */
+ if (ret)
+ return ret;
+ src = (void *)__get_free_page(GFP_NOIO |
+ __GFP_NOWARN |
+ __GFP_NORETRY);
+ if (src) {
+ copy_page(src, buf);
+ } else {
+ WARN_ON_ONCE(1);
+ hb = NULL; /* Go synchronous */
+ src = buf;
+ }
+ }
+ } else {
+ src = buf;
+ }
+ return hib_submit_io(REQ_OP_WRITE, REQ_SYNC, offset, src, hb);
+}
+
+static void release_swap_writer(struct swap_map_handle *handle)
+{
+ if (handle->cur)
+ free_page((unsigned long)handle->cur);
+ handle->cur = NULL;
+}
+
+static int get_swap_writer(struct swap_map_handle *handle)
+{
+ int ret;
+
+ ret = swsusp_swap_check();
+ if (ret) {
+ if (ret != -ENOSPC)
+ pr_err("Cannot find swap device, try swapon -a\n");
+ return ret;
+ }
+ handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
+ if (!handle->cur) {
+ ret = -ENOMEM;
+ goto err_close;
+ }
+ handle->cur_swap = alloc_swapdev_block(root_swap);
+ if (!handle->cur_swap) {
+ ret = -ENOSPC;
+ goto err_rel;
+ }
+ handle->k = 0;
+ handle->reqd_free_pages = reqd_free_pages();
+ handle->first_sector = handle->cur_swap;
+ return 0;
+err_rel:
+ release_swap_writer(handle);
+err_close:
+ swsusp_close(FMODE_WRITE);
+ return ret;
+}
+
+static int swap_write_page(struct swap_map_handle *handle, void *buf,
+ struct hib_bio_batch *hb)
+{
+ int error = 0;
+ sector_t offset;
+
+ if (!handle->cur)
+ return -EINVAL;
+ offset = alloc_swapdev_block(root_swap);
+ error = write_page(buf, offset, hb);
+ if (error)
+ return error;
+ handle->cur->entries[handle->k++] = offset;
+ if (handle->k >= MAP_PAGE_ENTRIES) {
+ offset = alloc_swapdev_block(root_swap);
+ if (!offset)
+ return -ENOSPC;
+ handle->cur->next_swap = offset;
+ error = write_page(handle->cur, handle->cur_swap, hb);
+ if (error)
+ goto out;
+ clear_page(handle->cur);
+ handle->cur_swap = offset;
+ handle->k = 0;
+
+ if (hb && low_free_pages() <= handle->reqd_free_pages) {
+ error = hib_wait_io(hb);
+ if (error)
+ goto out;
+ /*
+ * Recalculate the number of required free pages, to
+ * make sure we never take more than half.
+ */
+ handle->reqd_free_pages = reqd_free_pages();
+ }
+ }
+ out:
+ return error;
+}
+
+static int flush_swap_writer(struct swap_map_handle *handle)
+{
+ if (handle->cur && handle->cur_swap)
+ return write_page(handle->cur, handle->cur_swap, NULL);
+ else
+ return -EINVAL;
+}
+
+static int swap_writer_finish(struct swap_map_handle *handle,
+ unsigned int flags, int error)
+{
+ if (!error) {
+ flush_swap_writer(handle);
+ pr_info("S");
+ error = mark_swapfiles(handle, flags);
+ pr_cont("|\n");
+ }
+
+ if (error)
+ free_all_swap_pages(root_swap);
+ release_swap_writer(handle);
+ swsusp_close(FMODE_WRITE);
+
+ return error;
+}
+
+/* We need to remember how much compressed data we need to read. */
+#define LZO_HEADER sizeof(size_t)
+
+/* Number of pages/bytes we'll compress at one time. */
+#define LZO_UNC_PAGES 32
+#define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE)
+
+/* Number of pages/bytes we need for compressed data (worst case). */
+#define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \
+ LZO_HEADER, PAGE_SIZE)
+#define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
+
+/* Maximum number of threads for compression/decompression. */
+#define LZO_THREADS 3
+
+/* Minimum/maximum number of pages for read buffering. */
+#define LZO_MIN_RD_PAGES 1024
+#define LZO_MAX_RD_PAGES 8192
+
+
+/**
+ * save_image - save the suspend image data
+ */
+
+static int save_image(struct swap_map_handle *handle,
+ struct snapshot_handle *snapshot,
+ unsigned int nr_to_write)
+{
+ unsigned int m;
+ int ret;
+ int nr_pages;
+ int err2;
+ struct hib_bio_batch hb;
+ ktime_t start;
+ ktime_t stop;
+
+ hib_init_batch(&hb);
+
+ pr_info("Saving image data pages (%u pages)...\n",
+ nr_to_write);
+ m = nr_to_write / 10;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ start = ktime_get();
+ while (1) {
+ ret = snapshot_read_next(snapshot);
+ if (ret <= 0)
+ break;
+ ret = swap_write_page(handle, data_of(*snapshot), &hb);
+ if (ret)
+ break;
+ if (!(nr_pages % m))
+ pr_info("Image saving progress: %3d%%\n",
+ nr_pages / m * 10);
+ nr_pages++;
+ }
+ err2 = hib_wait_io(&hb);
+ stop = ktime_get();
+ if (!ret)
+ ret = err2;
+ if (!ret)
+ pr_info("Image saving done\n");
+ swsusp_show_speed(start, stop, nr_to_write, "Wrote");
+ return ret;
+}
+
+/**
+ * Structure used for CRC32.
+ */
+struct crc_data {
+ struct task_struct *thr; /* thread */
+ atomic_t ready; /* ready to start flag */
+ atomic_t stop; /* ready to stop flag */
+ unsigned run_threads; /* nr current threads */
+ wait_queue_head_t go; /* start crc update */
+ wait_queue_head_t done; /* crc update done */
+ u32 *crc32; /* points to handle's crc32 */
+ size_t *unc_len[LZO_THREADS]; /* uncompressed lengths */
+ unsigned char *unc[LZO_THREADS]; /* uncompressed data */
+};
+
+/**
+ * CRC32 update function that runs in its own thread.
+ */
+static int crc32_threadfn(void *data)
+{
+ struct crc_data *d = data;
+ unsigned i;
+
+ while (1) {
+ wait_event(d->go, atomic_read(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ for (i = 0; i < d->run_threads; i++)
+ *d->crc32 = crc32_le(*d->crc32,
+ d->unc[i], *d->unc_len[i]);
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
+/**
+ * Structure used for LZO data compression.
+ */
+struct cmp_data {
+ struct task_struct *thr; /* thread */
+ atomic_t ready; /* ready to start flag */
+ atomic_t stop; /* ready to stop flag */
+ int ret; /* return code */
+ wait_queue_head_t go; /* start compression */
+ wait_queue_head_t done; /* compression done */
+ size_t unc_len; /* uncompressed length */
+ size_t cmp_len; /* compressed length */
+ unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
+ unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
+ unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */
+};
+
+/**
+ * Compression function that runs in its own thread.
+ */
+static int lzo_compress_threadfn(void *data)
+{
+ struct cmp_data *d = data;
+
+ while (1) {
+ wait_event(d->go, atomic_read(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ d->ret = -1;
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ d->ret = lzo1x_1_compress(d->unc, d->unc_len,
+ d->cmp + LZO_HEADER, &d->cmp_len,
+ d->wrk);
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
+
+/**
+ * save_image_lzo - Save the suspend image data compressed with LZO.
+ * @handle: Swap map handle to use for saving the image.
+ * @snapshot: Image to read data from.
+ * @nr_to_write: Number of pages to save.
+ */
+static int save_image_lzo(struct swap_map_handle *handle,
+ struct snapshot_handle *snapshot,
+ unsigned int nr_to_write)
+{
+ unsigned int m;
+ int ret = 0;
+ int nr_pages;
+ int err2;
+ struct hib_bio_batch hb;
+ ktime_t start;
+ ktime_t stop;
+ size_t off;
+ unsigned thr, run_threads, nr_threads;
+ unsigned char *page = NULL;
+ struct cmp_data *data = NULL;
+ struct crc_data *crc = NULL;
+
+ hib_init_batch(&hb);
+
+ /*
+ * We'll limit the number of threads for compression to limit memory
+ * footprint.
+ */
+ nr_threads = num_online_cpus() - 1;
+ nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
+
+ page = (void *)__get_free_page(GFP_NOIO | __GFP_HIGH);
+ if (!page) {
+ pr_err("Failed to allocate LZO page\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ data = vmalloc(array_size(nr_threads, sizeof(*data)));
+ if (!data) {
+ pr_err("Failed to allocate LZO data\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ for (thr = 0; thr < nr_threads; thr++)
+ memset(&data[thr], 0, offsetof(struct cmp_data, go));
+
+ crc = kmalloc(sizeof(*crc), GFP_KERNEL);
+ if (!crc) {
+ pr_err("Failed to allocate crc\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ memset(crc, 0, offsetof(struct crc_data, go));
+
+ /*
+ * Start the compression threads.
+ */
+ for (thr = 0; thr < nr_threads; thr++) {
+ init_waitqueue_head(&data[thr].go);
+ init_waitqueue_head(&data[thr].done);
+
+ data[thr].thr = kthread_run(lzo_compress_threadfn,
+ &data[thr],
+ "image_compress/%u", thr);
+ if (IS_ERR(data[thr].thr)) {
+ data[thr].thr = NULL;
+ pr_err("Cannot start compression threads\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ }
+
+ /*
+ * Start the CRC32 thread.
+ */
+ init_waitqueue_head(&crc->go);
+ init_waitqueue_head(&crc->done);
+
+ handle->crc32 = 0;
+ crc->crc32 = &handle->crc32;
+ for (thr = 0; thr < nr_threads; thr++) {
+ crc->unc[thr] = data[thr].unc;
+ crc->unc_len[thr] = &data[thr].unc_len;
+ }
+
+ crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
+ if (IS_ERR(crc->thr)) {
+ crc->thr = NULL;
+ pr_err("Cannot start CRC32 thread\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ /*
+ * Adjust the number of required free pages after all allocations have
+ * been done. We don't want to run out of pages when writing.
+ */
+ handle->reqd_free_pages = reqd_free_pages();
+
+ pr_info("Using %u thread(s) for compression\n", nr_threads);
+ pr_info("Compressing and saving image data (%u pages)...\n",
+ nr_to_write);
+ m = nr_to_write / 10;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ start = ktime_get();
+ for (;;) {
+ for (thr = 0; thr < nr_threads; thr++) {
+ for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
+ ret = snapshot_read_next(snapshot);
+ if (ret < 0)
+ goto out_finish;
+
+ if (!ret)
+ break;
+
+ memcpy(data[thr].unc + off,
+ data_of(*snapshot), PAGE_SIZE);
+
+ if (!(nr_pages % m))
+ pr_info("Image saving progress: %3d%%\n",
+ nr_pages / m * 10);
+ nr_pages++;
+ }
+ if (!off)
+ break;
+
+ data[thr].unc_len = off;
+
+ atomic_set(&data[thr].ready, 1);
+ wake_up(&data[thr].go);
+ }
+
+ if (!thr)
+ break;
+
+ crc->run_threads = thr;
+ atomic_set(&crc->ready, 1);
+ wake_up(&crc->go);
+
+ for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
+ wait_event(data[thr].done,
+ atomic_read(&data[thr].stop));
+ atomic_set(&data[thr].stop, 0);
+
+ ret = data[thr].ret;
+
+ if (ret < 0) {
+ pr_err("LZO compression failed\n");
+ goto out_finish;
+ }
+
+ if (unlikely(!data[thr].cmp_len ||
+ data[thr].cmp_len >
+ lzo1x_worst_compress(data[thr].unc_len))) {
+ pr_err("Invalid LZO compressed length\n");
+ ret = -1;
+ goto out_finish;
+ }
+
+ *(size_t *)data[thr].cmp = data[thr].cmp_len;
+
+ /*
+ * Given we are writing one page at a time to disk, we
+ * copy that much from the buffer, although the last
+ * bit will likely be smaller than full page. This is
+ * OK - we saved the length of the compressed data, so
+ * any garbage at the end will be discarded when we
+ * read it.
+ */
+ for (off = 0;
+ off < LZO_HEADER + data[thr].cmp_len;
+ off += PAGE_SIZE) {
+ memcpy(page, data[thr].cmp + off, PAGE_SIZE);
+
+ ret = swap_write_page(handle, page, &hb);
+ if (ret)
+ goto out_finish;
+ }
+ }
+
+ wait_event(crc->done, atomic_read(&crc->stop));
+ atomic_set(&crc->stop, 0);
+ }
+
+out_finish:
+ err2 = hib_wait_io(&hb);
+ stop = ktime_get();
+ if (!ret)
+ ret = err2;
+ if (!ret)
+ pr_info("Image saving done\n");
+ swsusp_show_speed(start, stop, nr_to_write, "Wrote");
+out_clean:
+ if (crc) {
+ if (crc->thr)
+ kthread_stop(crc->thr);
+ kfree(crc);
+ }
+ if (data) {
+ for (thr = 0; thr < nr_threads; thr++)
+ if (data[thr].thr)
+ kthread_stop(data[thr].thr);
+ vfree(data);
+ }
+ if (page) free_page((unsigned long)page);
+
+ return ret;
+}
+
+/**
+ * enough_swap - Make sure we have enough swap to save the image.
+ *
+ * Returns TRUE or FALSE after checking the total amount of swap
+ * space avaiable from the resume partition.
+ */
+
+static int enough_swap(unsigned int nr_pages)
+{
+ unsigned int free_swap = count_swap_pages(root_swap, 1);
+ unsigned int required;
+
+ pr_debug("Free swap pages: %u\n", free_swap);
+
+ required = PAGES_FOR_IO + nr_pages;
+ return free_swap > required;
+}
+
+/**
+ * swsusp_write - Write entire image and metadata.
+ * @flags: flags to pass to the "boot" kernel in the image header
+ *
+ * It is important _NOT_ to umount filesystems at this point. We want
+ * them synced (in case something goes wrong) but we DO not want to mark
+ * filesystem clean: it is not. (And it does not matter, if we resume
+ * correctly, we'll mark system clean, anyway.)
+ */
+
+int swsusp_write(unsigned int flags)
+{
+ struct swap_map_handle handle;
+ struct snapshot_handle snapshot;
+ struct swsusp_info *header;
+ unsigned long pages;
+ int error;
+
+ pages = snapshot_get_image_size();
+ error = get_swap_writer(&handle);
+ if (error) {
+ pr_err("Cannot get swap writer\n");
+ return error;
+ }
+ if (flags & SF_NOCOMPRESS_MODE) {
+ if (!enough_swap(pages)) {
+ pr_err("Not enough free swap\n");
+ error = -ENOSPC;
+ goto out_finish;
+ }
+ }
+ memset(&snapshot, 0, sizeof(struct snapshot_handle));
+ error = snapshot_read_next(&snapshot);
+ if (error < (int)PAGE_SIZE) {
+ if (error >= 0)
+ error = -EFAULT;
+
+ goto out_finish;
+ }
+ header = (struct swsusp_info *)data_of(snapshot);
+ error = swap_write_page(&handle, header, NULL);
+ if (!error) {
+ error = (flags & SF_NOCOMPRESS_MODE) ?
+ save_image(&handle, &snapshot, pages - 1) :
+ save_image_lzo(&handle, &snapshot, pages - 1);
+ }
+out_finish:
+ error = swap_writer_finish(&handle, flags, error);
+ return error;
+}
+
+/**
+ * The following functions allow us to read data using a swap map
+ * in a file-alike way
+ */
+
+static void release_swap_reader(struct swap_map_handle *handle)
+{
+ struct swap_map_page_list *tmp;
+
+ while (handle->maps) {
+ if (handle->maps->map)
+ free_page((unsigned long)handle->maps->map);
+ tmp = handle->maps;
+ handle->maps = handle->maps->next;
+ kfree(tmp);
+ }
+ handle->cur = NULL;
+}
+
+static int get_swap_reader(struct swap_map_handle *handle,
+ unsigned int *flags_p)
+{
+ int error;
+ struct swap_map_page_list *tmp, *last;
+ sector_t offset;
+
+ *flags_p = swsusp_header->flags;
+
+ if (!swsusp_header->image) /* how can this happen? */
+ return -EINVAL;
+
+ handle->cur = NULL;
+ last = handle->maps = NULL;
+ offset = swsusp_header->image;
+ while (offset) {
+ tmp = kmalloc(sizeof(*handle->maps), GFP_KERNEL);
+ if (!tmp) {
+ release_swap_reader(handle);
+ return -ENOMEM;
+ }
+ memset(tmp, 0, sizeof(*tmp));
+ if (!handle->maps)
+ handle->maps = tmp;
+ if (last)
+ last->next = tmp;
+ last = tmp;
+
+ tmp->map = (struct swap_map_page *)
+ __get_free_page(GFP_NOIO | __GFP_HIGH);
+ if (!tmp->map) {
+ release_swap_reader(handle);
+ return -ENOMEM;
+ }
+
+ error = hib_submit_io(REQ_OP_READ, 0, offset, tmp->map, NULL);
+ if (error) {
+ release_swap_reader(handle);
+ return error;
+ }
+ offset = tmp->map->next_swap;
+ }
+ handle->k = 0;
+ handle->cur = handle->maps->map;
+ return 0;
+}
+
+static int swap_read_page(struct swap_map_handle *handle, void *buf,
+ struct hib_bio_batch *hb)
+{
+ sector_t offset;
+ int error;
+ struct swap_map_page_list *tmp;
+
+ if (!handle->cur)
+ return -EINVAL;
+ offset = handle->cur->entries[handle->k];
+ if (!offset)
+ return -EFAULT;
+ error = hib_submit_io(REQ_OP_READ, 0, offset, buf, hb);
+ if (error)
+ return error;
+ if (++handle->k >= MAP_PAGE_ENTRIES) {
+ handle->k = 0;
+ free_page((unsigned long)handle->maps->map);
+ tmp = handle->maps;
+ handle->maps = handle->maps->next;
+ kfree(tmp);
+ if (!handle->maps)
+ release_swap_reader(handle);
+ else
+ handle->cur = handle->maps->map;
+ }
+ return error;
+}
+
+static int swap_reader_finish(struct swap_map_handle *handle)
+{
+ release_swap_reader(handle);
+
+ return 0;
+}
+
+/**
+ * load_image - load the image using the swap map handle
+ * @handle and the snapshot handle @snapshot
+ * (assume there are @nr_pages pages to load)
+ */
+
+static int load_image(struct swap_map_handle *handle,
+ struct snapshot_handle *snapshot,
+ unsigned int nr_to_read)
+{
+ unsigned int m;
+ int ret = 0;
+ ktime_t start;
+ ktime_t stop;
+ struct hib_bio_batch hb;
+ int err2;
+ unsigned nr_pages;
+
+ hib_init_batch(&hb);
+
+ clean_pages_on_read = true;
+ pr_info("Loading image data pages (%u pages)...\n", nr_to_read);
+ m = nr_to_read / 10;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ start = ktime_get();
+ for ( ; ; ) {
+ ret = snapshot_write_next(snapshot);
+ if (ret <= 0)
+ break;
+ ret = swap_read_page(handle, data_of(*snapshot), &hb);
+ if (ret)
+ break;
+ if (snapshot->sync_read)
+ ret = hib_wait_io(&hb);
+ if (ret)
+ break;
+ if (!(nr_pages % m))
+ pr_info("Image loading progress: %3d%%\n",
+ nr_pages / m * 10);
+ nr_pages++;
+ }
+ err2 = hib_wait_io(&hb);
+ stop = ktime_get();
+ if (!ret)
+ ret = err2;
+ if (!ret) {
+ pr_info("Image loading done\n");
+ snapshot_write_finalize(snapshot);
+ if (!snapshot_image_loaded(snapshot))
+ ret = -ENODATA;
+ }
+ swsusp_show_speed(start, stop, nr_to_read, "Read");
+ return ret;
+}
+
+/**
+ * Structure used for LZO data decompression.
+ */
+struct dec_data {
+ struct task_struct *thr; /* thread */
+ atomic_t ready; /* ready to start flag */
+ atomic_t stop; /* ready to stop flag */
+ int ret; /* return code */
+ wait_queue_head_t go; /* start decompression */
+ wait_queue_head_t done; /* decompression done */
+ size_t unc_len; /* uncompressed length */
+ size_t cmp_len; /* compressed length */
+ unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
+ unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
+};
+
+/**
+ * Deompression function that runs in its own thread.
+ */
+static int lzo_decompress_threadfn(void *data)
+{
+ struct dec_data *d = data;
+
+ while (1) {
+ wait_event(d->go, atomic_read(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ d->ret = -1;
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ d->unc_len = LZO_UNC_SIZE;
+ d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len,
+ d->unc, &d->unc_len);
+ if (clean_pages_on_decompress)
+ flush_icache_range((unsigned long)d->unc,
+ (unsigned long)d->unc + d->unc_len);
+
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
+
+/**
+ * load_image_lzo - Load compressed image data and decompress them with LZO.
+ * @handle: Swap map handle to use for loading data.
+ * @snapshot: Image to copy uncompressed data into.
+ * @nr_to_read: Number of pages to load.
+ */
+static int load_image_lzo(struct swap_map_handle *handle,
+ struct snapshot_handle *snapshot,
+ unsigned int nr_to_read)
+{
+ unsigned int m;
+ int ret = 0;
+ int eof = 0;
+ struct hib_bio_batch hb;
+ ktime_t start;
+ ktime_t stop;
+ unsigned nr_pages;
+ size_t off;
+ unsigned i, thr, run_threads, nr_threads;
+ unsigned ring = 0, pg = 0, ring_size = 0,
+ have = 0, want, need, asked = 0;
+ unsigned long read_pages = 0;
+ unsigned char **page = NULL;
+ struct dec_data *data = NULL;
+ struct crc_data *crc = NULL;
+
+ hib_init_batch(&hb);
+
+ /*
+ * We'll limit the number of threads for decompression to limit memory
+ * footprint.
+ */
+ nr_threads = num_online_cpus() - 1;
+ nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
+
+ page = vmalloc(array_size(LZO_MAX_RD_PAGES, sizeof(*page)));
+ if (!page) {
+ pr_err("Failed to allocate LZO page\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ data = vmalloc(array_size(nr_threads, sizeof(*data)));
+ if (!data) {
+ pr_err("Failed to allocate LZO data\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ for (thr = 0; thr < nr_threads; thr++)
+ memset(&data[thr], 0, offsetof(struct dec_data, go));
+
+ crc = kmalloc(sizeof(*crc), GFP_KERNEL);
+ if (!crc) {
+ pr_err("Failed to allocate crc\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ memset(crc, 0, offsetof(struct crc_data, go));
+
+ clean_pages_on_decompress = true;
+
+ /*
+ * Start the decompression threads.
+ */
+ for (thr = 0; thr < nr_threads; thr++) {
+ init_waitqueue_head(&data[thr].go);
+ init_waitqueue_head(&data[thr].done);
+
+ data[thr].thr = kthread_run(lzo_decompress_threadfn,
+ &data[thr],
+ "image_decompress/%u", thr);
+ if (IS_ERR(data[thr].thr)) {
+ data[thr].thr = NULL;
+ pr_err("Cannot start decompression threads\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ }
+
+ /*
+ * Start the CRC32 thread.
+ */
+ init_waitqueue_head(&crc->go);
+ init_waitqueue_head(&crc->done);
+
+ handle->crc32 = 0;
+ crc->crc32 = &handle->crc32;
+ for (thr = 0; thr < nr_threads; thr++) {
+ crc->unc[thr] = data[thr].unc;
+ crc->unc_len[thr] = &data[thr].unc_len;
+ }
+
+ crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
+ if (IS_ERR(crc->thr)) {
+ crc->thr = NULL;
+ pr_err("Cannot start CRC32 thread\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ /*
+ * Set the number of pages for read buffering.
+ * This is complete guesswork, because we'll only know the real
+ * picture once prepare_image() is called, which is much later on
+ * during the image load phase. We'll assume the worst case and
+ * say that none of the image pages are from high memory.
+ */
+ if (low_free_pages() > snapshot_get_image_size())
+ read_pages = (low_free_pages() - snapshot_get_image_size()) / 2;
+ read_pages = clamp_val(read_pages, LZO_MIN_RD_PAGES, LZO_MAX_RD_PAGES);
+
+ for (i = 0; i < read_pages; i++) {
+ page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ?
+ GFP_NOIO | __GFP_HIGH :
+ GFP_NOIO | __GFP_NOWARN |
+ __GFP_NORETRY);
+
+ if (!page[i]) {
+ if (i < LZO_CMP_PAGES) {
+ ring_size = i;
+ pr_err("Failed to allocate LZO pages\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ } else {
+ break;
+ }
+ }
+ }
+ want = ring_size = i;
+
+ pr_info("Using %u thread(s) for decompression\n", nr_threads);
+ pr_info("Loading and decompressing image data (%u pages)...\n",
+ nr_to_read);
+ m = nr_to_read / 10;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ start = ktime_get();
+
+ ret = snapshot_write_next(snapshot);
+ if (ret <= 0)
+ goto out_finish;
+
+ for(;;) {
+ for (i = 0; !eof && i < want; i++) {
+ ret = swap_read_page(handle, page[ring], &hb);
+ if (ret) {
+ /*
+ * On real read error, finish. On end of data,
+ * set EOF flag and just exit the read loop.
+ */
+ if (handle->cur &&
+ handle->cur->entries[handle->k]) {
+ goto out_finish;
+ } else {
+ eof = 1;
+ break;
+ }
+ }
+ if (++ring >= ring_size)
+ ring = 0;
+ }
+ asked += i;
+ want -= i;
+
+ /*
+ * We are out of data, wait for some more.
+ */
+ if (!have) {
+ if (!asked)
+ break;
+
+ ret = hib_wait_io(&hb);
+ if (ret)
+ goto out_finish;
+ have += asked;
+ asked = 0;
+ if (eof)
+ eof = 2;
+ }
+
+ if (crc->run_threads) {
+ wait_event(crc->done, atomic_read(&crc->stop));
+ atomic_set(&crc->stop, 0);
+ crc->run_threads = 0;
+ }
+
+ for (thr = 0; have && thr < nr_threads; thr++) {
+ data[thr].cmp_len = *(size_t *)page[pg];
+ if (unlikely(!data[thr].cmp_len ||
+ data[thr].cmp_len >
+ lzo1x_worst_compress(LZO_UNC_SIZE))) {
+ pr_err("Invalid LZO compressed length\n");
+ ret = -1;
+ goto out_finish;
+ }
+
+ need = DIV_ROUND_UP(data[thr].cmp_len + LZO_HEADER,
+ PAGE_SIZE);
+ if (need > have) {
+ if (eof > 1) {
+ ret = -1;
+ goto out_finish;
+ }
+ break;
+ }
+
+ for (off = 0;
+ off < LZO_HEADER + data[thr].cmp_len;
+ off += PAGE_SIZE) {
+ memcpy(data[thr].cmp + off,
+ page[pg], PAGE_SIZE);
+ have--;
+ want++;
+ if (++pg >= ring_size)
+ pg = 0;
+ }
+
+ atomic_set(&data[thr].ready, 1);
+ wake_up(&data[thr].go);
+ }
+
+ /*
+ * Wait for more data while we are decompressing.
+ */
+ if (have < LZO_CMP_PAGES && asked) {
+ ret = hib_wait_io(&hb);
+ if (ret)
+ goto out_finish;
+ have += asked;
+ asked = 0;
+ if (eof)
+ eof = 2;
+ }
+
+ for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
+ wait_event(data[thr].done,
+ atomic_read(&data[thr].stop));
+ atomic_set(&data[thr].stop, 0);
+
+ ret = data[thr].ret;
+
+ if (ret < 0) {
+ pr_err("LZO decompression failed\n");
+ goto out_finish;
+ }
+
+ if (unlikely(!data[thr].unc_len ||
+ data[thr].unc_len > LZO_UNC_SIZE ||
+ data[thr].unc_len & (PAGE_SIZE - 1))) {
+ pr_err("Invalid LZO uncompressed length\n");
+ ret = -1;
+ goto out_finish;
+ }
+
+ for (off = 0;
+ off < data[thr].unc_len; off += PAGE_SIZE) {
+ memcpy(data_of(*snapshot),
+ data[thr].unc + off, PAGE_SIZE);
+
+ if (!(nr_pages % m))
+ pr_info("Image loading progress: %3d%%\n",
+ nr_pages / m * 10);
+ nr_pages++;
+
+ ret = snapshot_write_next(snapshot);
+ if (ret <= 0) {
+ crc->run_threads = thr + 1;
+ atomic_set(&crc->ready, 1);
+ wake_up(&crc->go);
+ goto out_finish;
+ }
+ }
+ }
+
+ crc->run_threads = thr;
+ atomic_set(&crc->ready, 1);
+ wake_up(&crc->go);
+ }
+
+out_finish:
+ if (crc->run_threads) {
+ wait_event(crc->done, atomic_read(&crc->stop));
+ atomic_set(&crc->stop, 0);
+ }
+ stop = ktime_get();
+ if (!ret) {
+ pr_info("Image loading done\n");
+ snapshot_write_finalize(snapshot);
+ if (!snapshot_image_loaded(snapshot))
+ ret = -ENODATA;
+ if (!ret) {
+ if (swsusp_header->flags & SF_CRC32_MODE) {
+ if(handle->crc32 != swsusp_header->crc32) {
+ pr_err("Invalid image CRC32!\n");
+ ret = -ENODATA;
+ }
+ }
+ }
+ }
+ swsusp_show_speed(start, stop, nr_to_read, "Read");
+out_clean:
+ for (i = 0; i < ring_size; i++)
+ free_page((unsigned long)page[i]);
+ if (crc) {
+ if (crc->thr)
+ kthread_stop(crc->thr);
+ kfree(crc);
+ }
+ if (data) {
+ for (thr = 0; thr < nr_threads; thr++)
+ if (data[thr].thr)
+ kthread_stop(data[thr].thr);
+ vfree(data);
+ }
+ vfree(page);
+
+ return ret;
+}
+
+/**
+ * swsusp_read - read the hibernation image.
+ * @flags_p: flags passed by the "frozen" kernel in the image header should
+ * be written into this memory location
+ */
+
+int swsusp_read(unsigned int *flags_p)
+{
+ int error;
+ struct swap_map_handle handle;
+ struct snapshot_handle snapshot;
+ struct swsusp_info *header;
+
+ memset(&snapshot, 0, sizeof(struct snapshot_handle));
+ error = snapshot_write_next(&snapshot);
+ if (error < (int)PAGE_SIZE)
+ return error < 0 ? error : -EFAULT;
+ header = (struct swsusp_info *)data_of(snapshot);
+ error = get_swap_reader(&handle, flags_p);
+ if (error)
+ goto end;
+ if (!error)
+ error = swap_read_page(&handle, header, NULL);
+ if (!error) {
+ error = (*flags_p & SF_NOCOMPRESS_MODE) ?
+ load_image(&handle, &snapshot, header->pages - 1) :
+ load_image_lzo(&handle, &snapshot, header->pages - 1);
+ }
+ swap_reader_finish(&handle);
+end:
+ if (!error)
+ pr_debug("Image successfully loaded\n");
+ else
+ pr_debug("Error %d resuming\n", error);
+ return error;
+}
+
+/**
+ * swsusp_check - Check for swsusp signature in the resume device
+ */
+
+int swsusp_check(void)
+{
+ int error;
+
+ hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device,
+ FMODE_READ, NULL);
+ if (!IS_ERR(hib_resume_bdev)) {
+ set_blocksize(hib_resume_bdev, PAGE_SIZE);
+ clear_page(swsusp_header);
+ error = hib_submit_io(REQ_OP_READ, 0,
+ swsusp_resume_block,
+ swsusp_header, NULL);
+ if (error)
+ goto put;
+
+ if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) {
+ memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
+ /* Reset swap signature now */
+ error = hib_submit_io(REQ_OP_WRITE, REQ_SYNC,
+ swsusp_resume_block,
+ swsusp_header, NULL);
+ } else {
+ error = -EINVAL;
+ }
+
+put:
+ if (error)
+ blkdev_put(hib_resume_bdev, FMODE_READ);
+ else
+ pr_debug("Image signature found, resuming\n");
+ } else {
+ error = PTR_ERR(hib_resume_bdev);
+ }
+
+ if (error)
+ pr_debug("Image not found (code %d)\n", error);
+
+ return error;
+}
+
+/**
+ * swsusp_close - close swap device.
+ */
+
+void swsusp_close(fmode_t mode)
+{
+ if (IS_ERR(hib_resume_bdev)) {
+ pr_debug("Image device not initialised\n");
+ return;
+ }
+
+ blkdev_put(hib_resume_bdev, mode);
+}
+
+/**
+ * swsusp_unmark - Unmark swsusp signature in the resume device
+ */
+
+#ifdef CONFIG_SUSPEND
+int swsusp_unmark(void)
+{
+ int error;
+
+ hib_submit_io(REQ_OP_READ, 0, swsusp_resume_block,
+ swsusp_header, NULL);
+ if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) {
+ memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10);
+ error = hib_submit_io(REQ_OP_WRITE, REQ_SYNC,
+ swsusp_resume_block,
+ swsusp_header, NULL);
+ } else {
+ pr_err("Cannot find swsusp signature!\n");
+ error = -ENODEV;
+ }
+
+ /*
+ * We just returned from suspend, we don't need the image any more.
+ */
+ free_all_swap_pages(root_swap);
+
+ return error;
+}
+#endif
+
+static int swsusp_header_init(void)
+{
+ swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
+ if (!swsusp_header)
+ panic("Could not allocate memory for swsusp_header\n");
+ return 0;
+}
+
+core_initcall(swsusp_header_init);
diff --git a/kernel/power/user.c b/kernel/power/user.c
new file mode 100644
index 0000000..2d8b60a
--- /dev/null
+++ b/kernel/power/user.c
@@ -0,0 +1,485 @@
+/*
+ * linux/kernel/power/user.c
+ *
+ * This file provides the user space interface for software suspend/resume.
+ *
+ * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
+ *
+ * This file is released under the GPLv2.
+ *
+ */
+
+#include <linux/suspend.h>
+#include <linux/syscalls.h>
+#include <linux/reboot.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
+#include <linux/pm.h>
+#include <linux/fs.h>
+#include <linux/compat.h>
+#include <linux/console.h>
+#include <linux/cpu.h>
+#include <linux/freezer.h>
+
+#include <linux/uaccess.h>
+
+#include "power.h"
+
+
+#define SNAPSHOT_MINOR 231
+
+static struct snapshot_data {
+ struct snapshot_handle handle;
+ int swap;
+ int mode;
+ bool frozen;
+ bool ready;
+ bool platform_support;
+ bool free_bitmaps;
+} snapshot_state;
+
+atomic_t snapshot_device_available = ATOMIC_INIT(1);
+
+static int snapshot_open(struct inode *inode, struct file *filp)
+{
+ struct snapshot_data *data;
+ int error, nr_calls = 0;
+
+ if (!hibernation_available())
+ return -EPERM;
+
+ lock_system_sleep();
+
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ error = -EBUSY;
+ goto Unlock;
+ }
+
+ if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
+ atomic_inc(&snapshot_device_available);
+ error = -ENOSYS;
+ goto Unlock;
+ }
+ nonseekable_open(inode, filp);
+ data = &snapshot_state;
+ filp->private_data = data;
+ memset(&data->handle, 0, sizeof(struct snapshot_handle));
+ if ((filp->f_flags & O_ACCMODE) == O_RDONLY) {
+ /* Hibernating. The image device should be accessible. */
+ data->swap = swsusp_resume_device ?
+ swap_type_of(swsusp_resume_device, 0, NULL) : -1;
+ data->mode = O_RDONLY;
+ data->free_bitmaps = false;
+ error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
+ if (error)
+ __pm_notifier_call_chain(PM_POST_HIBERNATION, --nr_calls, NULL);
+ } else {
+ /*
+ * Resuming. We may need to wait for the image device to
+ * appear.
+ */
+ wait_for_device_probe();
+
+ data->swap = -1;
+ data->mode = O_WRONLY;
+ error = __pm_notifier_call_chain(PM_RESTORE_PREPARE, -1, &nr_calls);
+ if (!error) {
+ error = create_basic_memory_bitmaps();
+ data->free_bitmaps = !error;
+ } else
+ nr_calls--;
+
+ if (error)
+ __pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL);
+ }
+ if (error)
+ atomic_inc(&snapshot_device_available);
+
+ data->frozen = false;
+ data->ready = false;
+ data->platform_support = false;
+
+ Unlock:
+ unlock_system_sleep();
+
+ return error;
+}
+
+static int snapshot_release(struct inode *inode, struct file *filp)
+{
+ struct snapshot_data *data;
+
+ lock_system_sleep();
+
+ swsusp_free();
+ data = filp->private_data;
+ free_all_swap_pages(data->swap);
+ if (data->frozen) {
+ pm_restore_gfp_mask();
+ free_basic_memory_bitmaps();
+ thaw_processes();
+ } else if (data->free_bitmaps) {
+ free_basic_memory_bitmaps();
+ }
+ pm_notifier_call_chain(data->mode == O_RDONLY ?
+ PM_POST_HIBERNATION : PM_POST_RESTORE);
+ atomic_inc(&snapshot_device_available);
+
+ unlock_system_sleep();
+
+ return 0;
+}
+
+static ssize_t snapshot_read(struct file *filp, char __user *buf,
+ size_t count, loff_t *offp)
+{
+ struct snapshot_data *data;
+ ssize_t res;
+ loff_t pg_offp = *offp & ~PAGE_MASK;
+
+ lock_system_sleep();
+
+ data = filp->private_data;
+ if (!data->ready) {
+ res = -ENODATA;
+ goto Unlock;
+ }
+ if (!pg_offp) { /* on page boundary? */
+ res = snapshot_read_next(&data->handle);
+ if (res <= 0)
+ goto Unlock;
+ } else {
+ res = PAGE_SIZE - pg_offp;
+ }
+
+ res = simple_read_from_buffer(buf, count, &pg_offp,
+ data_of(data->handle), res);
+ if (res > 0)
+ *offp += res;
+
+ Unlock:
+ unlock_system_sleep();
+
+ return res;
+}
+
+static ssize_t snapshot_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *offp)
+{
+ struct snapshot_data *data;
+ ssize_t res;
+ loff_t pg_offp = *offp & ~PAGE_MASK;
+
+ lock_system_sleep();
+
+ data = filp->private_data;
+
+ if (!pg_offp) {
+ res = snapshot_write_next(&data->handle);
+ if (res <= 0)
+ goto unlock;
+ } else {
+ res = PAGE_SIZE - pg_offp;
+ }
+
+ if (!data_of(data->handle)) {
+ res = -EINVAL;
+ goto unlock;
+ }
+
+ res = simple_write_to_buffer(data_of(data->handle), res, &pg_offp,
+ buf, count);
+ if (res > 0)
+ *offp += res;
+unlock:
+ unlock_system_sleep();
+
+ return res;
+}
+
+static long snapshot_ioctl(struct file *filp, unsigned int cmd,
+ unsigned long arg)
+{
+ int error = 0;
+ struct snapshot_data *data;
+ loff_t size;
+ sector_t offset;
+
+ if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
+ return -ENOTTY;
+ if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR)
+ return -ENOTTY;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (!mutex_trylock(&system_transition_mutex))
+ return -EBUSY;
+
+ lock_device_hotplug();
+ data = filp->private_data;
+
+ switch (cmd) {
+
+ case SNAPSHOT_FREEZE:
+ if (data->frozen)
+ break;
+
+ printk("Syncing filesystems ... ");
+ ksys_sync();
+ printk("done.\n");
+
+ error = freeze_processes();
+ if (error)
+ break;
+
+ error = create_basic_memory_bitmaps();
+ if (error)
+ thaw_processes();
+ else
+ data->frozen = true;
+
+ break;
+
+ case SNAPSHOT_UNFREEZE:
+ if (!data->frozen || data->ready)
+ break;
+ pm_restore_gfp_mask();
+ free_basic_memory_bitmaps();
+ data->free_bitmaps = false;
+ thaw_processes();
+ data->frozen = false;
+ break;
+
+ case SNAPSHOT_CREATE_IMAGE:
+ if (data->mode != O_RDONLY || !data->frozen || data->ready) {
+ error = -EPERM;
+ break;
+ }
+ pm_restore_gfp_mask();
+ error = hibernation_snapshot(data->platform_support);
+ if (!error) {
+ error = put_user(in_suspend, (int __user *)arg);
+ data->ready = !freezer_test_done && !error;
+ freezer_test_done = false;
+ }
+ break;
+
+ case SNAPSHOT_ATOMIC_RESTORE:
+ snapshot_write_finalize(&data->handle);
+ if (data->mode != O_WRONLY || !data->frozen ||
+ !snapshot_image_loaded(&data->handle)) {
+ error = -EPERM;
+ break;
+ }
+ error = hibernation_restore(data->platform_support);
+ break;
+
+ case SNAPSHOT_FREE:
+ swsusp_free();
+ memset(&data->handle, 0, sizeof(struct snapshot_handle));
+ data->ready = false;
+ /*
+ * It is necessary to thaw kernel threads here, because
+ * SNAPSHOT_CREATE_IMAGE may be invoked directly after
+ * SNAPSHOT_FREE. In that case, if kernel threads were not
+ * thawed, the preallocation of memory carried out by
+ * hibernation_snapshot() might run into problems (i.e. it
+ * might fail or even deadlock).
+ */
+ thaw_kernel_threads();
+ break;
+
+ case SNAPSHOT_PREF_IMAGE_SIZE:
+ image_size = arg;
+ break;
+
+ case SNAPSHOT_GET_IMAGE_SIZE:
+ if (!data->ready) {
+ error = -ENODATA;
+ break;
+ }
+ size = snapshot_get_image_size();
+ size <<= PAGE_SHIFT;
+ error = put_user(size, (loff_t __user *)arg);
+ break;
+
+ case SNAPSHOT_AVAIL_SWAP_SIZE:
+ size = count_swap_pages(data->swap, 1);
+ size <<= PAGE_SHIFT;
+ error = put_user(size, (loff_t __user *)arg);
+ break;
+
+ case SNAPSHOT_ALLOC_SWAP_PAGE:
+ if (data->swap < 0 || data->swap >= MAX_SWAPFILES) {
+ error = -ENODEV;
+ break;
+ }
+ offset = alloc_swapdev_block(data->swap);
+ if (offset) {
+ offset <<= PAGE_SHIFT;
+ error = put_user(offset, (loff_t __user *)arg);
+ } else {
+ error = -ENOSPC;
+ }
+ break;
+
+ case SNAPSHOT_FREE_SWAP_PAGES:
+ if (data->swap < 0 || data->swap >= MAX_SWAPFILES) {
+ error = -ENODEV;
+ break;
+ }
+ free_all_swap_pages(data->swap);
+ break;
+
+ case SNAPSHOT_S2RAM:
+ if (!data->frozen) {
+ error = -EPERM;
+ break;
+ }
+ /*
+ * Tasks are frozen and the notifiers have been called with
+ * PM_HIBERNATION_PREPARE
+ */
+ error = suspend_devices_and_enter(PM_SUSPEND_MEM);
+ data->ready = false;
+ break;
+
+ case SNAPSHOT_PLATFORM_SUPPORT:
+ data->platform_support = !!arg;
+ break;
+
+ case SNAPSHOT_POWER_OFF:
+ if (data->platform_support)
+ error = hibernation_platform_enter();
+ break;
+
+ case SNAPSHOT_SET_SWAP_AREA:
+ if (swsusp_swap_in_use()) {
+ error = -EPERM;
+ } else {
+ struct resume_swap_area swap_area;
+ dev_t swdev;
+
+ error = copy_from_user(&swap_area, (void __user *)arg,
+ sizeof(struct resume_swap_area));
+ if (error) {
+ error = -EFAULT;
+ break;
+ }
+
+ /*
+ * User space encodes device types as two-byte values,
+ * so we need to recode them
+ */
+ swdev = new_decode_dev(swap_area.dev);
+ if (swdev) {
+ offset = swap_area.offset;
+ data->swap = swap_type_of(swdev, offset, NULL);
+ if (data->swap < 0)
+ error = -ENODEV;
+ } else {
+ data->swap = -1;
+ error = -EINVAL;
+ }
+ }
+ break;
+
+ default:
+ error = -ENOTTY;
+
+ }
+
+ unlock_device_hotplug();
+ mutex_unlock(&system_transition_mutex);
+
+ return error;
+}
+
+#ifdef CONFIG_COMPAT
+
+struct compat_resume_swap_area {
+ compat_loff_t offset;
+ u32 dev;
+} __packed;
+
+static long
+snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ BUILD_BUG_ON(sizeof(loff_t) != sizeof(compat_loff_t));
+
+ switch (cmd) {
+ case SNAPSHOT_GET_IMAGE_SIZE:
+ case SNAPSHOT_AVAIL_SWAP_SIZE:
+ case SNAPSHOT_ALLOC_SWAP_PAGE: {
+ compat_loff_t __user *uoffset = compat_ptr(arg);
+ loff_t offset;
+ mm_segment_t old_fs;
+ int err;
+
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ err = snapshot_ioctl(file, cmd, (unsigned long) &offset);
+ set_fs(old_fs);
+ if (!err && put_user(offset, uoffset))
+ err = -EFAULT;
+ return err;
+ }
+
+ case SNAPSHOT_CREATE_IMAGE:
+ return snapshot_ioctl(file, cmd,
+ (unsigned long) compat_ptr(arg));
+
+ case SNAPSHOT_SET_SWAP_AREA: {
+ struct compat_resume_swap_area __user *u_swap_area =
+ compat_ptr(arg);
+ struct resume_swap_area swap_area;
+ mm_segment_t old_fs;
+ int err;
+
+ err = get_user(swap_area.offset, &u_swap_area->offset);
+ err |= get_user(swap_area.dev, &u_swap_area->dev);
+ if (err)
+ return -EFAULT;
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ err = snapshot_ioctl(file, SNAPSHOT_SET_SWAP_AREA,
+ (unsigned long) &swap_area);
+ set_fs(old_fs);
+ return err;
+ }
+
+ default:
+ return snapshot_ioctl(file, cmd, arg);
+ }
+}
+
+#endif /* CONFIG_COMPAT */
+
+static const struct file_operations snapshot_fops = {
+ .open = snapshot_open,
+ .release = snapshot_release,
+ .read = snapshot_read,
+ .write = snapshot_write,
+ .llseek = no_llseek,
+ .unlocked_ioctl = snapshot_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = snapshot_compat_ioctl,
+#endif
+};
+
+static struct miscdevice snapshot_device = {
+ .minor = SNAPSHOT_MINOR,
+ .name = "snapshot",
+ .fops = &snapshot_fops,
+};
+
+static int __init snapshot_device_init(void)
+{
+ return misc_register(&snapshot_device);
+};
+
+device_initcall(snapshot_device_init);
diff --git a/kernel/power/wakelock.c b/kernel/power/wakelock.c
new file mode 100644
index 0000000..4210152
--- /dev/null
+++ b/kernel/power/wakelock.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * kernel/power/wakelock.c
+ *
+ * User space wakeup sources support.
+ *
+ * Copyright (C) 2012 Rafael J. Wysocki <rjw@sisk.pl>
+ *
+ * This code is based on the analogous interface allowing user space to
+ * manipulate wakelocks on Android.
+ */
+
+#include <linux/capability.h>
+#include <linux/ctype.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/hrtimer.h>
+#include <linux/list.h>
+#include <linux/rbtree.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+#include "power.h"
+
+static DEFINE_MUTEX(wakelocks_lock);
+
+struct wakelock {
+ char *name;
+ struct rb_node node;
+ struct wakeup_source ws;
+#ifdef CONFIG_PM_WAKELOCKS_GC
+ struct list_head lru;
+#endif
+};
+
+static struct rb_root wakelocks_tree = RB_ROOT;
+
+ssize_t pm_show_wakelocks(char *buf, bool show_active)
+{
+ struct rb_node *node;
+ struct wakelock *wl;
+ char *str = buf;
+ char *end = buf + PAGE_SIZE;
+
+ mutex_lock(&wakelocks_lock);
+
+ for (node = rb_first(&wakelocks_tree); node; node = rb_next(node)) {
+ wl = rb_entry(node, struct wakelock, node);
+ if (wl->ws.active == show_active)
+ str += scnprintf(str, end - str, "%s ", wl->name);
+ }
+ if (str > buf)
+ str--;
+
+ str += scnprintf(str, end - str, "\n");
+
+ mutex_unlock(&wakelocks_lock);
+ return (str - buf);
+}
+
+#if CONFIG_PM_WAKELOCKS_LIMIT > 0
+static unsigned int number_of_wakelocks;
+
+static inline bool wakelocks_limit_exceeded(void)
+{
+ return number_of_wakelocks > CONFIG_PM_WAKELOCKS_LIMIT;
+}
+
+static inline void increment_wakelocks_number(void)
+{
+ number_of_wakelocks++;
+}
+
+static inline void decrement_wakelocks_number(void)
+{
+ number_of_wakelocks--;
+}
+#else /* CONFIG_PM_WAKELOCKS_LIMIT = 0 */
+static inline bool wakelocks_limit_exceeded(void) { return false; }
+static inline void increment_wakelocks_number(void) {}
+static inline void decrement_wakelocks_number(void) {}
+#endif /* CONFIG_PM_WAKELOCKS_LIMIT */
+
+#ifdef CONFIG_PM_WAKELOCKS_GC
+#define WL_GC_COUNT_MAX 100
+#define WL_GC_TIME_SEC 300
+
+static void __wakelocks_gc(struct work_struct *work);
+static LIST_HEAD(wakelocks_lru_list);
+static DECLARE_WORK(wakelock_work, __wakelocks_gc);
+static unsigned int wakelocks_gc_count;
+
+static inline void wakelocks_lru_add(struct wakelock *wl)
+{
+ list_add(&wl->lru, &wakelocks_lru_list);
+}
+
+static inline void wakelocks_lru_most_recent(struct wakelock *wl)
+{
+ list_move(&wl->lru, &wakelocks_lru_list);
+}
+
+static void __wakelocks_gc(struct work_struct *work)
+{
+ struct wakelock *wl, *aux;
+ ktime_t now;
+
+ mutex_lock(&wakelocks_lock);
+
+ now = ktime_get();
+ list_for_each_entry_safe_reverse(wl, aux, &wakelocks_lru_list, lru) {
+ u64 idle_time_ns;
+ bool active;
+
+ spin_lock_irq(&wl->ws.lock);
+ idle_time_ns = ktime_to_ns(ktime_sub(now, wl->ws.last_time));
+ active = wl->ws.active;
+ spin_unlock_irq(&wl->ws.lock);
+
+ if (idle_time_ns < ((u64)WL_GC_TIME_SEC * NSEC_PER_SEC))
+ break;
+
+ if (!active) {
+ wakeup_source_remove(&wl->ws);
+ rb_erase(&wl->node, &wakelocks_tree);
+ list_del(&wl->lru);
+ kfree(wl->name);
+ kfree(wl);
+ decrement_wakelocks_number();
+ }
+ }
+ wakelocks_gc_count = 0;
+
+ mutex_unlock(&wakelocks_lock);
+}
+
+static void wakelocks_gc(void)
+{
+ if (++wakelocks_gc_count <= WL_GC_COUNT_MAX)
+ return;
+
+ schedule_work(&wakelock_work);
+}
+#else /* !CONFIG_PM_WAKELOCKS_GC */
+static inline void wakelocks_lru_add(struct wakelock *wl) {}
+static inline void wakelocks_lru_most_recent(struct wakelock *wl) {}
+static inline void wakelocks_gc(void) {}
+#endif /* !CONFIG_PM_WAKELOCKS_GC */
+
+static struct wakelock *wakelock_lookup_add(const char *name, size_t len,
+ bool add_if_not_found)
+{
+ struct rb_node **node = &wakelocks_tree.rb_node;
+ struct rb_node *parent = *node;
+ struct wakelock *wl;
+
+ while (*node) {
+ int diff;
+
+ parent = *node;
+ wl = rb_entry(*node, struct wakelock, node);
+ diff = strncmp(name, wl->name, len);
+ if (diff == 0) {
+ if (wl->name[len])
+ diff = -1;
+ else
+ return wl;
+ }
+ if (diff < 0)
+ node = &(*node)->rb_left;
+ else
+ node = &(*node)->rb_right;
+ }
+ if (!add_if_not_found)
+ return ERR_PTR(-EINVAL);
+
+ if (wakelocks_limit_exceeded())
+ return ERR_PTR(-ENOSPC);
+
+ /* Not found, we have to add a new one. */
+ wl = kzalloc(sizeof(*wl), GFP_KERNEL);
+ if (!wl)
+ return ERR_PTR(-ENOMEM);
+
+ wl->name = kstrndup(name, len, GFP_KERNEL);
+ if (!wl->name) {
+ kfree(wl);
+ return ERR_PTR(-ENOMEM);
+ }
+ wl->ws.name = wl->name;
+ wl->ws.last_time = ktime_get();
+ wakeup_source_add(&wl->ws);
+ rb_link_node(&wl->node, parent, node);
+ rb_insert_color(&wl->node, &wakelocks_tree);
+ wakelocks_lru_add(wl);
+ increment_wakelocks_number();
+ return wl;
+}
+
+int pm_wake_lock(const char *buf)
+{
+ const char *str = buf;
+ struct wakelock *wl;
+ u64 timeout_ns = 0;
+ size_t len;
+ int ret = 0;
+
+ if (!capable(CAP_BLOCK_SUSPEND))
+ return -EPERM;
+
+ while (*str && !isspace(*str))
+ str++;
+
+ len = str - buf;
+ if (!len)
+ return -EINVAL;
+
+ if (*str && *str != '\n') {
+ /* Find out if there's a valid timeout string appended. */
+ ret = kstrtou64(skip_spaces(str), 10, &timeout_ns);
+ if (ret)
+ return -EINVAL;
+ }
+
+ mutex_lock(&wakelocks_lock);
+
+ wl = wakelock_lookup_add(buf, len, true);
+ if (IS_ERR(wl)) {
+ ret = PTR_ERR(wl);
+ goto out;
+ }
+ if (timeout_ns) {
+ u64 timeout_ms = timeout_ns + NSEC_PER_MSEC - 1;
+
+ do_div(timeout_ms, NSEC_PER_MSEC);
+ __pm_wakeup_event(&wl->ws, timeout_ms);
+ } else {
+ __pm_stay_awake(&wl->ws);
+ }
+
+ wakelocks_lru_most_recent(wl);
+
+ out:
+ mutex_unlock(&wakelocks_lock);
+ return ret;
+}
+
+int pm_wake_unlock(const char *buf)
+{
+ struct wakelock *wl;
+ size_t len;
+ int ret = 0;
+
+ if (!capable(CAP_BLOCK_SUSPEND))
+ return -EPERM;
+
+ len = strlen(buf);
+ if (!len)
+ return -EINVAL;
+
+ if (buf[len-1] == '\n')
+ len--;
+
+ if (!len)
+ return -EINVAL;
+
+ mutex_lock(&wakelocks_lock);
+
+ wl = wakelock_lookup_add(buf, len, false);
+ if (IS_ERR(wl)) {
+ ret = PTR_ERR(wl);
+ goto out;
+ }
+ __pm_relax(&wl->ws);
+
+ wakelocks_lru_most_recent(wl);
+ wakelocks_gc();
+
+ out:
+ mutex_unlock(&wakelocks_lock);
+ return ret;
+}