static int snapshot_open(struct inode *inode, struct file *filp)
{
struct snapshot_data *data;
int error;
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;
}
if(create_basic_memory_bitmaps()) {
atomic_inc(&snapshot_device_available);
error = -ENOMEM;
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;
error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
if (error)
pm_notifier_call_chain(PM_POST_HIBERNATION);
} 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);
if (error)
pm_notifier_call_chain(PM_POST_RESTORE);
}
if (error) {
free_basic_memory_bitmaps();
atomic_inc(&snapshot_device_available);
}
data->frozen = 0;
data->ready = 0;
data->platform_support = 0;
Unlock:
unlock_system_sleep();
return error;
}
static int load_image_and_restore(void)
{
int error;
unsigned int flags;
pr_debug("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;
}
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;
}
error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
if (error)
goto Exit;
/* Allocate memory management structures */
error = create_basic_memory_bitmaps();
if (error)
goto Exit;
printk("Syncing filesystems ... ");
sys_sync();
printk("done.\n");
error = prepare_processes();
if (error)
goto Finish;
if (hibernation_mode == HIBERNATION_TESTPROC) {
printk("swsusp debug: Waiting for 5 seconds.\n");
mdelay(5000);
goto Thaw;
}
error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
if (in_suspend && !error) {
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");
swsusp_free();
}
Thaw:
unprepare_processes();
Finish:
free_basic_memory_bitmaps();
Exit:
pm_notifier_call_chain(PM_POST_HIBERNATION);
atomic_inc(&snapshot_device_available);
Unlock:
mutex_unlock(&pm_mutex);
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 int snapshot_release(struct inode *inode, struct file *filp)
{
struct snapshot_data *data;
swsusp_free();
free_basic_memory_bitmaps();
data = filp->private_data;
free_all_swap_pages(data->swap);
if (data->frozen) {
mutex_lock(&pm_mutex);
thaw_processes();
mutex_unlock(&pm_mutex);
}
atomic_inc(&snapshot_device_available);
return 0;
}
static int snapshot_release(struct inode *inode, struct file *filp)
{
struct snapshot_data *data;
mutex_lock(&pm_mutex);
swsusp_free();
free_basic_memory_bitmaps();
data = filp->private_data;
free_all_swap_pages(data->swap);
if (data->frozen)
thaw_processes();
pm_notifier_call_chain(data->mode == O_WRONLY ?
PM_POST_HIBERNATION : PM_POST_RESTORE);
atomic_inc(&snapshot_device_available);
mutex_unlock(&pm_mutex);
return 0;
}
/**
* hibernate - Carry out system hibernation, including saving the image.
*/
int hibernate(void)
{
int error, nr_calls = 0;
bool snapshot_test = false;
if (!hibernation_available()) {
pr_debug("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;
}
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");
sys_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;
pr_debug("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 {
pr_debug("Image restored successfully.\n");
}
Free_bitmaps:
free_basic_memory_bitmaps();
Thaw:
unlock_device_hotplug();
if (snapshot_test) {
pr_debug("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();
return error;
}
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;
}
/**
* 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_snaphot() 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;
unsigned int flags;
/*
* 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 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 hibernation image partition %s\n", resume_file);
if (resume_delay) {
printk(KERN_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:
pr_debug("PM: Hibernation image partition %d:%d present\n",
MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
pr_debug("PM: 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;
}
pm_prepare_console();
error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
if (error)
goto Close_Finish;
pr_debug("PM: Preparing processes for restore.\n");
error = freeze_processes();
if (error)
goto Close_Finish;
pr_debug("PM: Loading hibernation image.\n");
lock_device_hotplug();
error = create_basic_memory_bitmaps();
if (error)
goto Thaw;
error = swsusp_read(&flags);
swsusp_close(FMODE_READ);
if (!error)
hibernation_restore(flags & SF_PLATFORM_MODE);
printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
swsusp_free();
free_basic_memory_bitmaps();
Thaw:
unlock_device_hotplug();
thaw_processes();
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: Hibernation image not present or could not be loaded.\n");
return error;
Close_Finish:
swsusp_close(FMODE_READ);
goto Finish;
}
/**
* hibernate - Carry out system hibernation, including saving the image.
*/
int hibernate(void)
{
int error;
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;
}
pm_prepare_console();
error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
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 = freeze_processes();
if (error)
goto Free_bitmaps;
error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
if (error)
goto Thaw;
if (freezer_test_done) {
freezer_test_done = false;
goto Thaw;
}
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;
pr_debug("PM: writing image.\n");
error = swsusp_write(flags);
swsusp_free();
if (!error)
power_down();
in_suspend = 0;
pm_restore_gfp_mask();
} else {
pr_debug("PM: Image restored successfully.\n");
}
Thaw:
thaw_processes();
Free_bitmaps:
free_basic_memory_bitmaps();
Exit:
pm_notifier_call_chain(PM_POST_HIBERNATION);
pm_restore_console();
atomic_inc(&snapshot_device_available);
Unlock:
unlock_system_sleep();
return error;
}
static int software_resume(void)
{
int error;
unsigned int flags;
/*
* 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) {
if (!strlen(resume_file)) {
mutex_unlock(&pm_mutex);
return -ENOENT;
}
swsusp_resume_device = name_to_dev_t(resume_file);
pr_debug("PM: Resume from partition %s\n", resume_file);
} else {
pr_debug("PM: Resume from partition %d:%d\n",
MAJOR(swsusp_resume_device),
MINOR(swsusp_resume_device));
}
if (noresume) {
/**
* FIXME: If noresume is specified, we need to find the
* partition and reset it back to normal swap space.
*/
mutex_unlock(&pm_mutex);
return 0;
}
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;
goto Unlock;
}
pm_prepare_console();
error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
if (error)
goto Finish;
error = create_basic_memory_bitmaps();
if (error)
goto Finish;
pr_debug("PM: Preparing processes for restore.\n");
error = prepare_processes();
if (error) {
swsusp_close();
goto Done;
}
pr_debug("PM: Reading hibernation image.\n");
error = swsusp_read(&flags);
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();
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;
}
static int software_resume(void)
{
int error;
mutex_lock(&pm_mutex);
if (!swsusp_resume_device) {
if (!strlen(resume_file)) {
mutex_unlock(&pm_mutex);
return -ENOENT;
}
swsusp_resume_device = name_to_dev_t(resume_file);
pr_debug("swsusp: Resume From Partition %s\n", resume_file);
} else {
pr_debug("swsusp: Resume From Partition %d:%d\n",
MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
}
if (noresume) {
/**
* FIXME: If noresume is specified, we need to find the partition
* and reset it back to normal swap space.
*/
mutex_unlock(&pm_mutex);
return 0;
}
pr_debug("PM: Checking swsusp image.\n");
error = swsusp_check();
if (error)
goto Unlock;
error = create_basic_memory_bitmaps();
if (error)
goto Unlock;
pr_debug("PM: Preparing processes for restore.\n");
error = prepare_processes();
if (error) {
swsusp_close();
goto Done;
}
pr_debug("PM: Reading swsusp image.\n");
error = swsusp_read();
if (error) {
swsusp_free();
goto Thaw;
}
pr_debug("PM: Preparing devices for restore.\n");
suspend_console();
error = device_suspend(PMSG_PRETHAW);
if (error)
goto Free;
error = disable_nonboot_cpus();
if (!error)
swsusp_resume();
enable_nonboot_cpus();
Free:
swsusp_free();
device_resume();
resume_console();
Thaw:
printk(KERN_ERR "PM: Restore failed, recovering.\n");
unprepare_processes();
Done:
free_basic_memory_bitmaps();
/* For success case, the suspend path will release the lock */
Unlock:
mutex_unlock(&pm_mutex);
pr_debug("PM: Resume from disk failed.\n");
return 0;
}
int pm_suspend_disk(void)
{
int error;
error = prepare_processes();
if (error)
return error;
if (pm_disk_mode == PM_DISK_TESTPROC) {
printk("swsusp debug: Waiting for 5 seconds.\n");
mdelay(5000);
goto Thaw;
}
/* Allocate memory management structures */
error = create_basic_memory_bitmaps();
if (error)
goto Thaw;
/* Free memory before shutting down devices. */
error = swsusp_shrink_memory();
if (error)
goto Finish;
error = platform_prepare();
if (error)
goto Finish;
suspend_console();
error = device_suspend(PMSG_FREEZE);
if (error) {
printk(KERN_ERR "PM: Some devices failed to suspend\n");
goto Resume_devices;
}
error = disable_nonboot_cpus();
if (error)
goto Enable_cpus;
if (pm_disk_mode == PM_DISK_TEST) {
printk("swsusp debug: Waiting for 5 seconds.\n");
mdelay(5000);
goto Enable_cpus;
}
pr_debug("PM: snapshotting memory.\n");
in_suspend = 1;
error = swsusp_suspend();
if (error)
goto Enable_cpus;
if (in_suspend) {
enable_nonboot_cpus();
platform_finish();
device_resume();
resume_console();
pr_debug("PM: writing image.\n");
error = swsusp_write();
if (!error)
power_down(pm_disk_mode);
else {
swsusp_free();
goto Finish;
}
} else {
pr_debug("PM: Image restored successfully.\n");
}
swsusp_free();
Enable_cpus:
enable_nonboot_cpus();
Resume_devices:
platform_finish();
device_resume();
resume_console();
Finish:
free_basic_memory_bitmaps();
Thaw:
unprepare_processes();
return error;
}
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(&pm_mutex))
return -EBUSY;
lock_device_hotplug();
data = filp->private_data;
switch (cmd) {
case SNAPSHOT_FREEZE:
if (data->frozen)
break;
printk("Syncing filesystems ... ");
sys_sync();
printk("done.\n");
error = freeze_processes();
if (error)
break;
error = create_basic_memory_bitmaps();
if (error)
thaw_processes();
else
data->frozen = 1;
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 = 0;
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 = 0;
/*
* 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 = 0;
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(&pm_mutex);
return error;
}