static inline int snapshot_restore(int platform_suspend)
{
int error;
mutex_lock(&pm_mutex);
pm_prepare_console();
if (platform_suspend) {
error = platform_prepare();
if (error)
goto Finish;
}
suspend_console();
error = device_suspend(PMSG_PRETHAW);
if (error)
goto Resume_devices;
error = disable_nonboot_cpus();
if (!error)
error = swsusp_resume();
enable_nonboot_cpus();
Resume_devices:
if (platform_suspend)
platform_finish();
device_resume();
resume_console();
Finish:
pm_restore_console();
mutex_unlock(&pm_mutex);
return error;
}
static int software_resume(void)
{
int error;
if (noresume) {
/**
* FIXME: If noresume is specified, we need to find the partition
* and reset it back to normal swap space.
*/
return 0;
}
pr_debug("PM: Reading pmdisk image.\n");
if ((error = swsusp_read()))
goto Done;
pr_debug("PM: Preparing system for restore.\n");
if ((error = prepare()))
goto Free;
barrier();
mb();
pr_debug("PM: Restoring saved image.\n");
swsusp_resume();
pr_debug("PM: Restore failed, recovering.n");
finish();
Free:
swsusp_free();
Done:
pr_debug("PM: Resume from disk failed.\n");
return 0;
}
int hibernation_restore(int platform_mode)
{
int error;
pm_prepare_console();
suspend_console();
error = device_suspend(PMSG_PRETHAW);
if (error)
goto Finish;
error = platform_pre_restore(platform_mode);
if (!error) {
error = disable_nonboot_cpus();
if (!error)
error = swsusp_resume();
enable_nonboot_cpus();
}
platform_restore_cleanup(platform_mode);
device_resume();
Finish:
resume_console();
pm_restore_console();
return error;
}
static int software_resume(void)
{
int error;
down(&pm_sem);
if (!swsusp_resume_device) {
if (!strlen(resume_file)) {
up(&pm_sem);
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.
*/
up(&pm_sem);
return 0;
}
pr_debug("PM: Checking swsusp image.\n");
if ((error = swsusp_check()))
goto Done;
pr_debug("PM: Preparing processes for restore.\n");
if ((error = prepare_processes())) {
swsusp_close();
goto Done;
}
pr_debug("PM: Reading swsusp image.\n");
if ((error = swsusp_read()))
goto Cleanup;
pr_debug("PM: Preparing devices for restore.\n");
if ((error = device_suspend(PMSG_FREEZE))) {
printk("Some devices failed to suspend\n");
goto Free;
}
mb();
pr_debug("PM: Restoring saved image.\n");
swsusp_resume();
pr_debug("PM: Restore failed, recovering.n");
device_resume();
Free:
swsusp_free();
Cleanup:
unprepare_processes();
Done:
/* For success case, the suspend path will release the lock */
up(&pm_sem);
pr_debug("PM: Resume from disk failed.\n");
return 0;
}
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;
}
static int snapshot_ioctl(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
int error = 0;
struct snapshot_data *data;
loff_t offset, avail;
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;
data = filp->private_data;
switch (cmd) {
case SNAPSHOT_FREEZE:
if (data->frozen)
break;
down(&pm_sem);
disable_nonboot_cpus();
if (freeze_processes()) {
thaw_processes();
enable_nonboot_cpus();
error = -EBUSY;
}
up(&pm_sem);
if (!error)
data->frozen = 1;
break;
case SNAPSHOT_UNFREEZE:
if (!data->frozen)
break;
down(&pm_sem);
thaw_processes();
enable_nonboot_cpus();
up(&pm_sem);
data->frozen = 0;
break;
case SNAPSHOT_ATOMIC_SNAPSHOT:
if (data->mode != O_RDONLY || !data->frozen || data->ready) {
error = -EPERM;
break;
}
down(&pm_sem);
/* Free memory before shutting down devices. */
error = swsusp_shrink_memory();
if (!error) {
error = device_suspend(PMSG_FREEZE);
if (!error) {
in_suspend = 1;
error = swsusp_suspend();
device_resume();
}
}
up(&pm_sem);
if (!error)
error = put_user(in_suspend, (unsigned int __user *)arg);
if (!error)
data->ready = 1;
break;
case SNAPSHOT_ATOMIC_RESTORE:
if (data->mode != O_WRONLY || !data->frozen ||
!snapshot_image_loaded(&data->handle)) {
error = -EPERM;
break;
}
down(&pm_sem);
pm_prepare_console();
error = device_suspend(PMSG_FREEZE);
if (!error) {
error = swsusp_resume();
device_resume();
}
pm_restore_console();
up(&pm_sem);
break;
case SNAPSHOT_FREE:
swsusp_free();
memset(&data->handle, 0, sizeof(struct snapshot_handle));
data->ready = 0;
break;
case SNAPSHOT_SET_IMAGE_SIZE:
image_size = arg;
break;
case SNAPSHOT_AVAIL_SWAP:
avail = count_swap_pages(data->swap, 1);
avail <<= PAGE_SHIFT;
error = put_user(avail, (loff_t __user *)arg);
break;
case SNAPSHOT_GET_SWAP_PAGE:
if (data->swap < 0 || data->swap >= MAX_SWAPFILES) {
error = -ENODEV;
break;
}
if (!data->bitmap) {
data->bitmap = alloc_bitmap(count_swap_pages(data->swap, 0));
if (!data->bitmap) {
error = -ENOMEM;
break;
}
}
offset = alloc_swap_page(data->swap, data->bitmap);
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, data->bitmap);
free_bitmap(data->bitmap);
data->bitmap = NULL;
break;
case SNAPSHOT_SET_SWAP_FILE:
if (!data->bitmap) {
/*
* User space encodes device types as two-byte values,
* so we need to recode them
*/
if (old_decode_dev(arg)) {
data->swap = swap_type_of(old_decode_dev(arg));
if (data->swap < 0)
error = -ENODEV;
} else {
data->swap = -1;
error = -EINVAL;
}
} else {
error = -EPERM;
}
break;
case SNAPSHOT_S2RAM:
if (!data->frozen) {
error = -EPERM;
break;
}
if (down_trylock(&pm_sem)) {
error = -EBUSY;
break;
}
if (pm_ops->prepare) {
error = pm_ops->prepare(PM_SUSPEND_MEM);
if (error)
goto OutS3;
}
/* Put devices to sleep */
error = device_suspend(PMSG_SUSPEND);
if (error) {
printk(KERN_ERR "Failed to suspend some devices.\n");
} else {
/* Enter S3, system is already frozen */
suspend_enter(PM_SUSPEND_MEM);
/* Wake up devices */
device_resume();
}
if (pm_ops->finish)
pm_ops->finish(PM_SUSPEND_MEM);
OutS3:
up(&pm_sem);
break;
default:
error = -ENOTTY;
}
return error;
}