linux/kernel/power/hibernate.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

1007 lines
23 KiB
C

/*
* kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
*
* Copyright (c) 2003 Patrick Mochel
* Copyright (c) 2003 Open Source Development Lab
* Copyright (c) 2004 Pavel Machek <pavel@suse.cz>
* Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
*
* This file is released under the GPLv2.
*/
#include <linux/suspend.h>
#include <linux/syscalls.h>
#include <linux/reboot.h>
#include <linux/string.h>
#include <linux/device.h>
#include <linux/kmod.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/pm.h>
#include <linux/console.h>
#include <linux/cpu.h>
#include <linux/freezer.h>
#include <linux/gfp.h>
#include <scsi/scsi_scan.h>
#include <asm/suspend.h>
#include "power.h"
static int noresume = 0;
static char resume_file[256] = CONFIG_PM_STD_PARTITION;
dev_t swsusp_resume_device;
sector_t swsusp_resume_block;
int in_suspend __nosavedata = 0;
enum {
HIBERNATION_INVALID,
HIBERNATION_PLATFORM,
HIBERNATION_TEST,
HIBERNATION_TESTPROC,
HIBERNATION_SHUTDOWN,
HIBERNATION_REBOOT,
/* keep last */
__HIBERNATION_AFTER_LAST
};
#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
static int hibernation_mode = HIBERNATION_SHUTDOWN;
static struct platform_hibernation_ops *hibernation_ops;
/**
* hibernation_set_ops - set the global hibernate operations
* @ops: the hibernation operations to use in subsequent hibernation transitions
*/
void hibernation_set_ops(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)) {
WARN_ON(1);
return;
}
mutex_lock(&pm_mutex);
hibernation_ops = ops;
if (ops)
hibernation_mode = HIBERNATION_PLATFORM;
else if (hibernation_mode == HIBERNATION_PLATFORM)
hibernation_mode = HIBERNATION_SHUTDOWN;
mutex_unlock(&pm_mutex);
}
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)
{
printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
mdelay(5000);
}
static int hibernation_testmode(int mode)
{
if (hibernation_mode == mode) {
hibernation_debug_sleep();
return 1;
}
return 0;
}
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_testmode(int mode) { return 0; }
static int hibernation_test(int level) { return 0; }
#endif /* !CONFIG_PM_DEBUG */
/**
* platform_begin - tell the platform driver that we're starting
* hibernation
*/
static int platform_begin(int platform_mode)
{
return (platform_mode && hibernation_ops) ?
hibernation_ops->begin() : 0;
}
/**
* platform_end - tell the platform driver that we've entered the
* working state
*/
static void platform_end(int platform_mode)
{
if (platform_mode && hibernation_ops)
hibernation_ops->end();
}
/**
* platform_pre_snapshot - prepare the machine for hibernation using the
* platform driver if so configured and return an error code if it fails
*/
static int platform_pre_snapshot(int platform_mode)
{
return (platform_mode && hibernation_ops) ?
hibernation_ops->pre_snapshot() : 0;
}
/**
* platform_leave - prepare the machine for switching to the normal mode
* of operation using the platform driver (called with interrupts disabled)
*/
static void platform_leave(int platform_mode)
{
if (platform_mode && hibernation_ops)
hibernation_ops->leave();
}
/**
* platform_finish - switch the machine to the normal mode of operation
* using the platform driver (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 the platform for the restoration 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 the platform 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 the platform from a failure to suspend
* devices.
*/
static void platform_recover(int platform_mode)
{
if (platform_mode && hibernation_ops && hibernation_ops->recover)
hibernation_ops->recover();
}
/**
* swsusp_show_speed - print the time elapsed between two events.
* @start: Starting event.
* @stop: Final event.
* @nr_pages - number of pages processed between @start and @stop
* @msg - introductory message to print
*/
void swsusp_show_speed(struct timeval *start, struct timeval *stop,
unsigned nr_pages, char *msg)
{
s64 elapsed_centisecs64;
int centisecs;
int k;
int kps;
elapsed_centisecs64 = timeval_to_ns(stop) - timeval_to_ns(start);
do_div(elapsed_centisecs64, NSEC_PER_SEC / 100);
centisecs = elapsed_centisecs64;
if (centisecs == 0)
centisecs = 1; /* avoid div-by-zero */
k = nr_pages * (PAGE_SIZE / 1024);
kps = (k * 100) / centisecs;
printk(KERN_INFO "PM: %s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n",
msg, k,
centisecs / 100, centisecs % 100,
kps / 1000, (kps % 1000) / 10);
}
/**
* create_image - freeze devices that need to be frozen with interrupts
* off, create the hibernation image and thaw those devices. Control
* reappears in this routine after a restore.
*/
static int create_image(int platform_mode)
{
int error;
error = arch_prepare_suspend();
if (error)
return error;
/* At this point, dpm_suspend_start() has been called, but *not*
* dpm_suspend_noirq(). We *must* call dpm_suspend_noirq() now.
* Otherwise, drivers for some devices (e.g. interrupt controllers)
* become desynchronized with the actual state of the hardware
* at resume time, and evil weirdness ensues.
*/
error = dpm_suspend_noirq(PMSG_FREEZE);
if (error) {
printk(KERN_ERR "PM: 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)
|| hibernation_testmode(HIBERNATION_TEST))
goto Enable_cpus;
local_irq_disable();
error = sysdev_suspend(PMSG_FREEZE);
if (error) {
printk(KERN_ERR "PM: Some system devices failed to power down, "
"aborting hibernation\n");
goto Enable_irqs;
}
if (hibernation_test(TEST_CORE))
goto Power_up;
in_suspend = 1;
save_processor_state();
error = swsusp_arch_suspend();
if (error)
printk(KERN_ERR "PM: Error %d creating hibernation image\n",
error);
/* Restore control flow magically appears here */
restore_processor_state();
if (!in_suspend)
platform_leave(platform_mode);
Power_up:
sysdev_resume();
/* NOTE: dpm_resume_noirq() is just a resume() for devices
* that suspended with irqs off ... no overall powerup.
*/
Enable_irqs:
local_irq_enable();
Enable_cpus:
enable_nonboot_cpus();
Platform_finish:
platform_finish(platform_mode);
dpm_resume_noirq(in_suspend ?
(error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
return error;
}
/**
* hibernation_snapshot - quiesce devices and create the hibernation
* snapshot image.
* @platform_mode - if set, use the platform driver, if available, to
* prepare the platform firmware for the power transition.
*
* Must be called with pm_mutex held
*/
int hibernation_snapshot(int platform_mode)
{
int error;
gfp_t saved_mask;
error = platform_begin(platform_mode);
if (error)
return error;
/* Preallocate image memory before shutting down devices. */
error = hibernate_preallocate_memory();
if (error)
goto Close;
suspend_console();
saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
error = dpm_suspend_start(PMSG_FREEZE);
if (error)
goto Recover_platform;
if (hibernation_test(TEST_DEVICES))
goto Recover_platform;
error = create_image(platform_mode);
/* Control returns here after successful restore */
Resume_devices:
/* We may need to release the preallocated image pages here. */
if (error || !in_suspend)
swsusp_free();
dpm_resume_end(in_suspend ?
(error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
set_gfp_allowed_mask(saved_mask);
resume_console();
Close:
platform_end(platform_mode);
return error;
Recover_platform:
platform_recover(platform_mode);
goto Resume_devices;
}
/**
* resume_target_kernel - prepare devices that need to be suspended with
* interrupts off, 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_noirq(PMSG_QUIESCE);
if (error) {
printk(KERN_ERR "PM: Some devices failed to power down, "
"aborting resume\n");
return error;
}
error = platform_pre_restore(platform_mode);
if (error)
goto Cleanup;
error = disable_nonboot_cpus();
if (error)
goto Enable_cpus;
local_irq_disable();
error = sysdev_suspend(PMSG_QUIESCE);
if (error)
goto Enable_irqs;
/* We'll ignore saved state, but this gets preempt count (etc) right */
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 place where
* swsusp_arch_suspend() was called
*/
BUG_ON(!error);
/* This call to restore_highmem() undos 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();
sysdev_resume();
Enable_irqs:
local_irq_enable();
Enable_cpus:
enable_nonboot_cpus();
Cleanup:
platform_restore_cleanup(platform_mode);
dpm_resume_noirq(PMSG_RECOVER);
return error;
}
/**
* hibernation_restore - quiesce devices and restore the hibernation
* snapshot image. If successful, control returns in hibernation_snaphot()
* @platform_mode - if set, use the platform driver, if available, to
* prepare the platform firmware for the transition.
*
* Must be called with pm_mutex held
*/
int hibernation_restore(int platform_mode)
{
int error;
gfp_t saved_mask;
pm_prepare_console();
suspend_console();
saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
error = dpm_suspend_start(PMSG_QUIESCE);
if (!error) {
error = resume_target_kernel(platform_mode);
dpm_resume_end(PMSG_RECOVER);
}
set_gfp_allowed_mask(saved_mask);
resume_console();
pm_restore_console();
return error;
}
/**
* hibernation_platform_enter - enter the hibernation state using the
* platform driver (if available)
*/
int hibernation_platform_enter(void)
{
int error;
gfp_t saved_mask;
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();
saved_mask = clear_gfp_allowed_mask(GFP_IOFS);
error = dpm_suspend_start(PMSG_HIBERNATE);
if (error) {
if (hibernation_ops->recover)
hibernation_ops->recover();
goto Resume_devices;
}
error = dpm_suspend_noirq(PMSG_HIBERNATE);
if (error)
goto Resume_devices;
error = hibernation_ops->prepare();
if (error)
goto Platform_finish;
error = disable_nonboot_cpus();
if (error)
goto Platform_finish;
local_irq_disable();
sysdev_suspend(PMSG_HIBERNATE);
hibernation_ops->enter();
/* We should never get here */
while (1);
/*
* We don't need to reenable the nonboot CPUs or resume consoles, since
* the system is going to be halted anyway.
*/
Platform_finish:
hibernation_ops->finish();
dpm_suspend_noirq(PMSG_RESTORE);
Resume_devices:
entering_platform_hibernation = false;
dpm_resume_end(PMSG_RESTORE);
set_gfp_allowed_mask(saved_mask);
resume_console();
Close:
hibernation_ops->end();
return error;
}
/**
* power_down - Shut the machine down for hibernation.
*
* Use the platform driver, if configured so; otherwise try
* to power off or reboot.
*/
static void power_down(void)
{
switch (hibernation_mode) {
case HIBERNATION_TEST:
case HIBERNATION_TESTPROC:
break;
case HIBERNATION_REBOOT:
kernel_restart(NULL);
break;
case HIBERNATION_PLATFORM:
hibernation_platform_enter();
case HIBERNATION_SHUTDOWN:
kernel_power_off();
break;
}
kernel_halt();
/*
* Valid image is on the disk, if we continue we risk serious data
* corruption after resume.
*/
printk(KERN_CRIT "PM: Please power down manually\n");
while(1);
}
static int prepare_processes(void)
{
int error = 0;
if (freeze_processes()) {
error = -EBUSY;
thaw_processes();
}
return error;
}
/**
* hibernate - The granpappy of the built-in hibernation management
*/
int hibernate(void)
{
int error;
mutex_lock(&pm_mutex);
/* The snapshot device should not be opened while we're running */
if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
error = -EBUSY;
goto Unlock;
}
pm_prepare_console();
error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
if (error)
goto Exit;
error = usermodehelper_disable();
if (error)
goto Exit;
/* Allocate memory management structures */
error = create_basic_memory_bitmaps();
if (error)
goto Exit;
printk(KERN_INFO "PM: Syncing filesystems ... ");
sys_sync();
printk("done.\n");
error = prepare_processes();
if (error)
goto Finish;
if (hibernation_test(TEST_FREEZER))
goto Thaw;
if (hibernation_testmode(HIBERNATION_TESTPROC))
goto Thaw;
error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
if (error)
goto Thaw;
if (in_suspend) {
unsigned int flags = 0;
if (hibernation_mode == HIBERNATION_PLATFORM)
flags |= SF_PLATFORM_MODE;
pr_debug("PM: writing image.\n");
error = swsusp_write(flags);
swsusp_free();
if (!error)
power_down();
} else {
pr_debug("PM: Image restored successfully.\n");
}
Thaw:
thaw_processes();
Finish:
free_basic_memory_bitmaps();
usermodehelper_enable();
Exit:
pm_notifier_call_chain(PM_POST_HIBERNATION);
pm_restore_console();
atomic_inc(&snapshot_device_available);
Unlock:
mutex_unlock(&pm_mutex);
return error;
}
/**
* software_resume - Resume from a saved image.
*
* Called as a late_initcall (so all devices are discovered and
* initialized), we call swsusp to see if we have a saved image or not.
* If so, we quiesce devices, the restore the saved image. We will
* return above (in hibernate() ) if everything goes well.
* Otherwise, we fail gracefully and return to the normally
* scheduled program.
*
*/
static int software_resume(void)
{
int error;
unsigned int flags;
/*
* If the user said "noresume".. bail out early.
*/
if (noresume)
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 pm_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(&pm_mutex, SINGLE_DEPTH_NESTING);
if (swsusp_resume_device)
goto Check_image;
if (!strlen(resume_file)) {
error = -ENOENT;
goto Unlock;
}
pr_debug("PM: Checking image partition %s\n", resume_file);
/* Check if the device is there */
swsusp_resume_device = name_to_dev_t(resume_file);
if (!swsusp_resume_device) {
/*
* Some device discovery might still be in progress; we need
* to wait for this to finish.
*/
wait_for_device_probe();
/*
* We can't depend on SCSI devices being available after loading
* one of their modules until scsi_complete_async_scans() is
* called and the resume device usually is a SCSI one.
*/
scsi_complete_async_scans();
swsusp_resume_device = name_to_dev_t(resume_file);
if (!swsusp_resume_device) {
error = -ENODEV;
goto Unlock;
}
}
Check_image:
pr_debug("PM: Resume from partition %d:%d\n",
MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
pr_debug("PM: Checking 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;
}
pm_prepare_console();
error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
if (error)
goto close_finish;
error = usermodehelper_disable();
if (error)
goto close_finish;
error = create_basic_memory_bitmaps();
if (error)
goto close_finish;
pr_debug("PM: Preparing processes for restore.\n");
error = prepare_processes();
if (error) {
swsusp_close(FMODE_READ);
goto Done;
}
pr_debug("PM: Reading hibernation image.\n");
error = swsusp_read(&flags);
swsusp_close(FMODE_READ);
if (!error)
hibernation_restore(flags & SF_PLATFORM_MODE);
printk(KERN_ERR "PM: Restore failed, recovering.\n");
swsusp_free();
thaw_processes();
Done:
free_basic_memory_bitmaps();
usermodehelper_enable();
Finish:
pm_notifier_call_chain(PM_POST_RESTORE);
pm_restore_console();
atomic_inc(&snapshot_device_available);
/* For success case, the suspend path will release the lock */
Unlock:
mutex_unlock(&pm_mutex);
pr_debug("PM: Resume from disk failed.\n");
return error;
close_finish:
swsusp_close(FMODE_READ);
goto Finish;
}
late_initcall(software_resume);
static const char * const hibernation_modes[] = {
[HIBERNATION_PLATFORM] = "platform",
[HIBERNATION_SHUTDOWN] = "shutdown",
[HIBERNATION_REBOOT] = "reboot",
[HIBERNATION_TEST] = "test",
[HIBERNATION_TESTPROC] = "testproc",
};
/**
* disk - Control hibernation mode
*
* Suspend-to-disk can be handled in several ways. We have a few options
* for putting the system to sleep - using the platform driver (e.g. ACPI
* or other hibernation_ops), powering off the system or rebooting the
* system (for testing) as well as the two test modes.
*
* The system can support 'platform', and that is known a priori (and
* encoded by the presence of hibernation_ops). However, the user may
* choose 'shutdown' or 'reboot' as alternatives, as well as one fo the
* test modes, 'test' or 'testproc'.
*
* show() will display what the mode is currently set to.
* store() will accept one of
*
* 'platform'
* 'shutdown'
* 'reboot'
* 'test'
* 'testproc'
*
* It will only change to 'platform' if the system
* supports it (as determined by having hibernation_ops).
*/
static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
int i;
char *start = buf;
for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
if (!hibernation_modes[i])
continue;
switch (i) {
case HIBERNATION_SHUTDOWN:
case HIBERNATION_REBOOT:
case HIBERNATION_TEST:
case HIBERNATION_TESTPROC:
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;
p = memchr(buf, '\n', n);
len = p ? p - buf : n;
mutex_lock(&pm_mutex);
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:
case HIBERNATION_TEST:
case HIBERNATION_TESTPROC:
hibernation_mode = mode;
break;
case HIBERNATION_PLATFORM:
if (hibernation_ops)
hibernation_mode = mode;
else
error = -EINVAL;
}
} else
error = -EINVAL;
if (!error)
pr_debug("PM: Hibernation mode set to '%s'\n",
hibernation_modes[mode]);
mutex_unlock(&pm_mutex);
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)
{
unsigned int maj, min;
dev_t res;
int ret = -EINVAL;
if (sscanf(buf, "%u:%u", &maj, &min) != 2)
goto out;
res = MKDEV(maj,min);
if (maj != MAJOR(res) || min != MINOR(res))
goto out;
mutex_lock(&pm_mutex);
swsusp_resume_device = res;
mutex_unlock(&pm_mutex);
printk(KERN_INFO "PM: Starting manual resume from disk\n");
noresume = 0;
software_resume();
ret = n;
out:
return ret;
}
power_attr(resume);
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 struct attribute * g[] = {
&disk_attr.attr,
&resume_attr.attr,
&image_size_attr.attr,
NULL,
};
static 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 noresume_setup(char *str)
{
noresume = 1;
return 1;
}
__setup("noresume", noresume_setup);
__setup("resume_offset=", resume_offset_setup);
__setup("resume=", resume_setup);