[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / power / user.c

/*
 * 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/console.h>
#include <linux/cpu.h>
#include <linux/freezer.h>

#include <asm/uaccess.h>

#include "power.h"

#define SNAPSHOT_MINOR	231

static struct snapshot_data {
	struct snapshot_handle handle;
	int swap;
	struct bitmap_page *bitmap;
	int mode;
	char frozen;
	char ready;
	char platform_suspend;
} snapshot_state;

static atomic_t device_available = ATOMIC_INIT(1);

static int snapshot_open(struct inode *inode, struct file *filp)
{
	struct snapshot_data *data;

	if (!atomic_add_unless(&device_available, -1, 0))
		return -EBUSY;

	if ((filp->f_flags & O_ACCMODE) == O_RDWR)
		return -ENOSYS;

	if(create_basic_memory_bitmaps())
		return -ENOMEM;

	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) {
		data->swap = swsusp_resume_device ?
			swap_type_of(swsusp_resume_device, 0, NULL) : -1;
		data->mode = O_RDONLY;
	} else {
		data->swap = -1;
		data->mode = O_WRONLY;
	}
	data->bitmap = NULL;
	data->frozen = 0;
	data->ready = 0;
	data->platform_suspend = 0;

	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, data->bitmap);
	free_bitmap(data->bitmap);
	if (data->frozen) {
		mutex_lock(&pm_mutex);
		thaw_processes();
		enable_nonboot_cpus();
		mutex_unlock(&pm_mutex);
	}
	atomic_inc(&device_available);
	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;

	data = filp->private_data;
	res = snapshot_read_next(&data->handle, count);
	if (res > 0) {
		if (copy_to_user(buf, data_of(data->handle), res))
			res = -EFAULT;
		else
			*offp = data->handle.offset;
	}
	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;

	data = filp->private_data;
	res = snapshot_write_next(&data->handle, count);
	if (res > 0) {
		if (copy_from_user(data_of(data->handle), buf, res))
			res = -EFAULT;
		else
			*offp = data->handle.offset;
	}
	return res;
}

static inline int platform_prepare(void)
{
	int error = 0;

	if (pm_ops && pm_ops->prepare)
		error = pm_ops->prepare(PM_SUSPEND_DISK);

	return error;
}

static inline void platform_finish(void)
{
	if (pm_ops && pm_ops->finish)
		pm_ops->finish(PM_SUSPEND_DISK);
}

static inline int snapshot_suspend(int platform_suspend)
{
	int error;

	mutex_lock(&pm_mutex);
	/* Free memory before shutting down devices. */
	error = swsusp_shrink_memory();
	if (error)
		goto Finish;

	if (platform_suspend) {
		error = platform_prepare();
		if (error)
			goto Finish;
	}
	suspend_console();
	error = device_suspend(PMSG_FREEZE);
	if (error)
		goto Resume_devices;

	error = disable_nonboot_cpus();
	if (!error) {
		in_suspend = 1;
		error = swsusp_suspend();
	}
	enable_nonboot_cpus();
 Resume_devices:
	if (platform_suspend)
		platform_finish();

	device_resume();
	resume_console();
 Finish:
	mutex_unlock(&pm_mutex);
	return error;
}

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 snapshot_ioctl(struct inode *inode, struct file *filp,
                          unsigned int cmd, unsigned long arg)
{
	int error = 0;
	struct snapshot_data *data;
	loff_t avail;
	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;

	data = filp->private_data;

	switch (cmd) {

	case SNAPSHOT_FREEZE:
		if (data->frozen)
			break;
		mutex_lock(&pm_mutex);
		if (freeze_processes()) {
			thaw_processes();
			error = -EBUSY;
		}
		mutex_unlock(&pm_mutex);
		if (!error)
			data->frozen = 1;
		break;

	case SNAPSHOT_UNFREEZE:
		if (!data->frozen)
			break;
		mutex_lock(&pm_mutex);
		thaw_processes();
		mutex_unlock(&pm_mutex);
		data->frozen = 0;
		break;

	case SNAPSHOT_ATOMIC_SNAPSHOT:
		if (data->mode != O_RDONLY || !data->frozen  || data->ready) {
			error = -EPERM;
			break;
		}
		error = snapshot_suspend(data->platform_suspend);
		if (!error)
			error = put_user(in_suspend, (unsigned int __user *)arg);
		if (!error)
			data->ready = 1;
		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 = snapshot_restore(data->platform_suspend);
		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_swapdev_block(data->swap, data->bitmap);
		if (offset) {
			offset <<= PAGE_SHIFT;
			error = put_user(offset, (sector_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),
							0, NULL);
				if (data->swap < 0)
					error = -ENODEV;
			} else {
				data->swap = -1;
				error = -EINVAL;
			}
		} else {
			error = -EPERM;
		}
		break;

	case SNAPSHOT_S2RAM:
		if (!pm_ops) {
			error = -ENOSYS;
			break;
		}

		if (!data->frozen) {
			error = -EPERM;
			break;
		}

		if (!mutex_trylock(&pm_mutex)) {
			error = -EBUSY;
			break;
		}

		if (pm_ops->prepare) {
			error = pm_ops->prepare(PM_SUSPEND_MEM);
			if (error)
				goto OutS3;
		}

		/* Put devices to sleep */
		suspend_console();
		error = device_suspend(PMSG_SUSPEND);
		if (error) {
			printk(KERN_ERR "Failed to suspend some devices.\n");
		} else {
			error = disable_nonboot_cpus();
			if (!error) {
				/* Enter S3, system is already frozen */
				suspend_enter(PM_SUSPEND_MEM);
				enable_nonboot_cpus();
			}
			/* Wake up devices */
			device_resume();
		}
		resume_console();
		if (pm_ops->finish)
			pm_ops->finish(PM_SUSPEND_MEM);

 OutS3:
		mutex_unlock(&pm_mutex);
		break;

	case SNAPSHOT_PMOPS:
		error = -EINVAL;

		switch (arg) {

		case PMOPS_PREPARE:
			if (pm_ops && pm_ops->enter) {
				data->platform_suspend = 1;
				error = 0;
			} else {
				error = -ENOSYS;
			}
			break;

		case PMOPS_ENTER:
			if (data->platform_suspend) {
				kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
				error = pm_ops->enter(PM_SUSPEND_DISK);
				error = 0;
			}
			break;

		case PMOPS_FINISH:
			if (data->platform_suspend)
				error = 0;

			break;

		default:
			printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg);

		}
		break;

	case SNAPSHOT_SET_SWAP_AREA:
		if (data->bitmap) {
			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 = old_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;

	}

	return error;
}

static const struct file_operations snapshot_fops = {
	.open = snapshot_open,
	.release = snapshot_release,
	.read = snapshot_read,
	.write = snapshot_write,
	.llseek = no_llseek,
	.ioctl = snapshot_ioctl,
};

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);
Commit	Line	Data
6e1819d6 RW	1	/*
	2	* linux/kernel/power/user.c
	3	*
	4	* This file provides the user space interface for software suspend/resume.
	5	*
	6	* Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
	7	*
	8	* This file is released under the GPLv2.
	9	*
	10	*/
	11
	12	#include <linux/suspend.h>
	13	#include <linux/syscalls.h>
3592695c	14	#include <linux/reboot.h>
6e1819d6 RW	15	#include <linux/string.h>
	16	#include <linux/device.h>
	17	#include <linux/miscdevice.h>
	18	#include <linux/mm.h>
	19	#include <linux/swap.h>
	20	#include <linux/swapops.h>
	21	#include <linux/pm.h>
	22	#include <linux/fs.h>
97c7801c	23	#include <linux/console.h>
e3920fb4	24	#include <linux/cpu.h>
7dfb7103	25	#include <linux/freezer.h>
6e1819d6 RW	26
	27	#include <asm/uaccess.h>
	28
	29	#include "power.h"
	30
	31	#define SNAPSHOT_MINOR 231
	32
	33	static struct snapshot_data {
	34	struct snapshot_handle handle;
	35	int swap;
	36	struct bitmap_page *bitmap;
	37	int mode;
	38	char frozen;
	39	char ready;
2b5b09b3	40	char platform_suspend;
6e1819d6 RW	41	} snapshot_state;
	42
	43	static atomic_t device_available = ATOMIC_INIT(1);
	44
	45	static int snapshot_open(struct inode inode, struct file filp)
	46	{
	47	struct snapshot_data *data;
	48
	49	if (!atomic_add_unless(&device_available, -1, 0))
	50	return -EBUSY;
	51
	52	if ((filp->f_flags & O_ACCMODE) == O_RDWR)
	53	return -ENOSYS;
	54
74dfd666 RW	55	if(create_basic_memory_bitmaps())
	56	return -ENOMEM;
	57
6e1819d6 RW	58	nonseekable_open(inode, filp);
	59	data = &snapshot_state;
	60	filp->private_data = data;
	61	memset(&data->handle, 0, sizeof(struct snapshot_handle));
	62	if ((filp->f_flags & O_ACCMODE) == O_RDONLY) {
915bae9e	63	data->swap = swsusp_resume_device ?
7bf23687	64	swap_type_of(swsusp_resume_device, 0, NULL) : -1;
6e1819d6 RW	65	data->mode = O_RDONLY;
	66	} else {
	67	data->swap = -1;
	68	data->mode = O_WRONLY;
	69	}
	70	data->bitmap = NULL;
	71	data->frozen = 0;
	72	data->ready = 0;
2b5b09b3	73	data->platform_suspend = 0;
6e1819d6 RW	74
	75	return 0;
	76	}
	77
	78	static int snapshot_release(struct inode inode, struct file filp)
	79	{
	80	struct snapshot_data *data;
	81
	82	swsusp_free();
74dfd666	83	free_basic_memory_bitmaps();
6e1819d6 RW	84	data = filp->private_data;
	85	free_all_swap_pages(data->swap, data->bitmap);
	86	free_bitmap(data->bitmap);
	87	if (data->frozen) {
a6d70980	88	mutex_lock(&pm_mutex);
6e1819d6 RW	89	thaw_processes();
6e1819d6 RW	90	enable_nonboot_cpus();
a6d70980	91	mutex_unlock(&pm_mutex);
6e1819d6 RW	92	}
	93	atomic_inc(&device_available);
	94	return 0;
	95	}
	96
	97	static ssize_t snapshot_read(struct file filp, char __user buf,
	98	size_t count, loff_t *offp)
	99	{
	100	struct snapshot_data *data;
	101	ssize_t res;
	102
	103	data = filp->private_data;
	104	res = snapshot_read_next(&data->handle, count);
	105	if (res > 0) {
	106	if (copy_to_user(buf, data_of(data->handle), res))
	107	res = -EFAULT;
	108	else
	109	*offp = data->handle.offset;
	110	}
	111	return res;
	112	}
	113
	114	static ssize_t snapshot_write(struct file filp, const char __user buf,
	115	size_t count, loff_t *offp)
	116	{
	117	struct snapshot_data *data;
	118	ssize_t res;
	119
	120	data = filp->private_data;
	121	res = snapshot_write_next(&data->handle, count);
	122	if (res > 0) {
	123	if (copy_from_user(data_of(data->handle), buf, res))
	124	res = -EFAULT;
	125	else
	126	*offp = data->handle.offset;
	127	}
	128	return res;
	129	}
	130
2b5b09b3 RW	131	static inline int platform_prepare(void)
	132	{
	133	int error = 0;
	134
	135	if (pm_ops && pm_ops->prepare)
	136	error = pm_ops->prepare(PM_SUSPEND_DISK);
	137
	138	return error;
	139	}
	140
	141	static inline void platform_finish(void)
	142	{
	143	if (pm_ops && pm_ops->finish)
	144	pm_ops->finish(PM_SUSPEND_DISK);
	145	}
	146
	147	static inline int snapshot_suspend(int platform_suspend)
25913052 RW	148	{
	149	int error;
	150
	151	mutex_lock(&pm_mutex);
	152	/* Free memory before shutting down devices. */
	153	error = swsusp_shrink_memory();
	154	if (error)
	155	goto Finish;
	156
2b5b09b3 RW	157	if (platform_suspend) {
	158	error = platform_prepare();
	159	if (error)
	160	goto Finish;
	161	}
25913052 RW	162	suspend_console();
	163	error = device_suspend(PMSG_FREEZE);
	164	if (error)
	165	goto Resume_devices;
	166
	167	error = disable_nonboot_cpus();
	168	if (!error) {
	169	in_suspend = 1;
	170	error = swsusp_suspend();
	171	}
	172	enable_nonboot_cpus();
	173	Resume_devices:
2b5b09b3 RW	174	if (platform_suspend)
	175	platform_finish();
	176
25913052 RW	177	device_resume();
	178	resume_console();
	179	Finish:
	180	mutex_unlock(&pm_mutex);
	181	return error;
	182	}
	183
2b5b09b3	184	static inline int snapshot_restore(int platform_suspend)
25913052 RW	185	{
	186	int error;
	187
	188	mutex_lock(&pm_mutex);
	189	pm_prepare_console();
2b5b09b3 RW	190	if (platform_suspend) {
	191	error = platform_prepare();
	192	if (error)
	193	goto Finish;
	194	}
25913052 RW	195	suspend_console();
	196	error = device_suspend(PMSG_PRETHAW);
	197	if (error)
	198	goto Resume_devices;
	199
	200	error = disable_nonboot_cpus();
	201	if (!error)
	202	error = swsusp_resume();
	203
	204	enable_nonboot_cpus();
	205	Resume_devices:
2b5b09b3 RW	206	if (platform_suspend)
	207	platform_finish();
	208
25913052 RW	209	device_resume();
25913052 RW	210	resume_console();
2b5b09b3	211	Finish:
25913052 RW	212	pm_restore_console();
	213	mutex_unlock(&pm_mutex);
	214	return error;
	215	}
	216
6e1819d6 RW	217	static int snapshot_ioctl(struct inode inode, struct file filp,
	218	unsigned int cmd, unsigned long arg)
	219	{
	220	int error = 0;
	221	struct snapshot_data *data;
3aef83e0 RW	222	loff_t avail;
3aef83e0 RW	223	sector_t offset;
6e1819d6 RW	224
	225	if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
	226	return -ENOTTY;
	227	if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR)
	228	return -ENOTTY;
	229	if (!capable(CAP_SYS_ADMIN))
	230	return -EPERM;
	231
	232	data = filp->private_data;
	233
	234	switch (cmd) {
	235
	236	case SNAPSHOT_FREEZE:
	237	if (data->frozen)
	238	break;
a6d70980	239	mutex_lock(&pm_mutex);
25913052 RW	240	if (freeze_processes()) {
	241	thaw_processes();
	242	error = -EBUSY;
6e1819d6	243	}
a6d70980	244	mutex_unlock(&pm_mutex);
6e1819d6 RW	245	if (!error)
	246	data->frozen = 1;
	247	break;
	248
	249	case SNAPSHOT_UNFREEZE:
	250	if (!data->frozen)
	251	break;
a6d70980	252	mutex_lock(&pm_mutex);
6e1819d6	253	thaw_processes();
a6d70980	254	mutex_unlock(&pm_mutex);
6e1819d6 RW	255	data->frozen = 0;
	256	break;
	257
	258	case SNAPSHOT_ATOMIC_SNAPSHOT:
	259	if (data->mode != O_RDONLY \|\| !data->frozen \|\| data->ready) {
	260	error = -EPERM;
	261	break;
	262	}
2b5b09b3	263	error = snapshot_suspend(data->platform_suspend);
6e1819d6 RW	264	if (!error)
	265	error = put_user(in_suspend, (unsigned int __user *)arg);
	266	if (!error)
	267	data->ready = 1;
	268	break;
	269
	270	case SNAPSHOT_ATOMIC_RESTORE:
8357376d	271	snapshot_write_finalize(&data->handle);
6e1819d6 RW	272	if (data->mode != O_WRONLY \|\| !data->frozen \|\|
	273	!snapshot_image_loaded(&data->handle)) {
	274	error = -EPERM;
	275	break;
	276	}
2b5b09b3	277	error = snapshot_restore(data->platform_suspend);
6e1819d6 RW	278	break;
	279
	280	case SNAPSHOT_FREE:
	281	swsusp_free();
	282	memset(&data->handle, 0, sizeof(struct snapshot_handle));
	283	data->ready = 0;
	284	break;
	285
	286	case SNAPSHOT_SET_IMAGE_SIZE:
	287	image_size = arg;
	288	break;
	289
	290	case SNAPSHOT_AVAIL_SWAP:
	291	avail = count_swap_pages(data->swap, 1);
	292	avail <<= PAGE_SHIFT;
	293	error = put_user(avail, (loff_t __user *)arg);
	294	break;
	295
	296	case SNAPSHOT_GET_SWAP_PAGE:
	297	if (data->swap < 0 \|\| data->swap >= MAX_SWAPFILES) {
	298	error = -ENODEV;
	299	break;
	300	}
	301	if (!data->bitmap) {
	302	data->bitmap = alloc_bitmap(count_swap_pages(data->swap, 0));
	303	if (!data->bitmap) {
	304	error = -ENOMEM;
	305	break;
	306	}
	307	}
3aef83e0	308	offset = alloc_swapdev_block(data->swap, data->bitmap);
6e1819d6 RW	309	if (offset) {
6e1819d6 RW	310	offset <<= PAGE_SHIFT;
3aef83e0	311	error = put_user(offset, (sector_t __user *)arg);
6e1819d6 RW	312	} else {
	313	error = -ENOSPC;
	314	}
	315	break;
	316
	317	case SNAPSHOT_FREE_SWAP_PAGES:
	318	if (data->swap < 0 \|\| data->swap >= MAX_SWAPFILES) {
	319	error = -ENODEV;
	320	break;
	321	}
	322	free_all_swap_pages(data->swap, data->bitmap);
	323	free_bitmap(data->bitmap);
	324	data->bitmap = NULL;
	325	break;
	326
	327	case SNAPSHOT_SET_SWAP_FILE:
	328	if (!data->bitmap) {
	329	/*
	330	* User space encodes device types as two-byte values,
	331	* so we need to recode them
	332	*/
	333	if (old_decode_dev(arg)) {
7bf23687 RW	334	data->swap = swap_type_of(old_decode_dev(arg),
7bf23687 RW	335	0, NULL);
6e1819d6 RW	336	if (data->swap < 0)
	337	error = -ENODEV;
	338	} else {
	339	data->swap = -1;
	340	error = -EINVAL;
	341	}
	342	} else {
	343	error = -EPERM;
	344	}
	345	break;
	346
9b238205	347	case SNAPSHOT_S2RAM:
2b5b09b3 RW	348	if (!pm_ops) {
	349	error = -ENOSYS;
	350	break;
	351	}
	352
9b238205 LT	353	if (!data->frozen) {
	354	error = -EPERM;
	355	break;
	356	}
	357
a6d70980	358	if (!mutex_trylock(&pm_mutex)) {
9b238205 LT	359	error = -EBUSY;
	360	break;
	361	}
	362
	363	if (pm_ops->prepare) {
	364	error = pm_ops->prepare(PM_SUSPEND_MEM);
	365	if (error)
	366	goto OutS3;
	367	}
	368
	369	/* Put devices to sleep */
97c7801c	370	suspend_console();
9b238205 LT	371	error = device_suspend(PMSG_SUSPEND);
	372	if (error) {
	373	printk(KERN_ERR "Failed to suspend some devices.\n");
	374	} else {
93c9a7ff RW	375	error = disable_nonboot_cpus();
	376	if (!error) {
	377	/* Enter S3, system is already frozen */
	378	suspend_enter(PM_SUSPEND_MEM);
	379	enable_nonboot_cpus();
	380	}
9b238205 LT	381	/* Wake up devices */
	382	device_resume();
	383	}
97c7801c	384	resume_console();
9b238205 LT	385	if (pm_ops->finish)
	386	pm_ops->finish(PM_SUSPEND_MEM);
	387
59a49335	388	OutS3:
a6d70980	389	mutex_unlock(&pm_mutex);
9b238205 LT	390	break;
9b238205 LT	391
3592695c	392	case SNAPSHOT_PMOPS:
2b5b09b3 RW	393	error = -EINVAL;
2b5b09b3 RW	394
3592695c SS	395	switch (arg) {
	396
	397	case PMOPS_PREPARE:
2b5b09b3 RW	398	if (pm_ops && pm_ops->enter) {
	399	data->platform_suspend = 1;
	400	error = 0;
	401	} else {
	402	error = -ENOSYS;
3592695c SS	403	}
	404	break;
	405
	406	case PMOPS_ENTER:
2b5b09b3 RW	407	if (data->platform_suspend) {
	408	kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
	409	error = pm_ops->enter(PM_SUSPEND_DISK);
436ce716	410	error = 0;
2b5b09b3	411	}
3592695c SS	412	break;
	413
	414	case PMOPS_FINISH:
2b5b09b3 RW	415	if (data->platform_suspend)
	416	error = 0;
	417
3592695c SS	418	break;
	419
	420	default:
	421	printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg);
3592695c SS	422
	423	}
	424	break;
	425
37b2ba12 RW	426	case SNAPSHOT_SET_SWAP_AREA:
	427	if (data->bitmap) {
	428	error = -EPERM;
	429	} else {
	430	struct resume_swap_area swap_area;
	431	dev_t swdev;
	432
	433	error = copy_from_user(&swap_area, (void __user *)arg,
	434	sizeof(struct resume_swap_area));
	435	if (error) {
	436	error = -EFAULT;
	437	break;
	438	}
	439
	440	/*
	441	* User space encodes device types as two-byte values,
	442	* so we need to recode them
	443	*/
	444	swdev = old_decode_dev(swap_area.dev);
	445	if (swdev) {
	446	offset = swap_area.offset;
7bf23687	447	data->swap = swap_type_of(swdev, offset, NULL);
37b2ba12 RW	448	if (data->swap < 0)
	449	error = -ENODEV;
	450	} else {
	451	data->swap = -1;
	452	error = -EINVAL;
	453	}
	454	}
	455	break;
	456
6e1819d6 RW	457	default:
	458	error = -ENOTTY;
	459
	460	}
	461
	462	return error;
	463	}
	464
15ad7cdc	465	static const struct file_operations snapshot_fops = {
6e1819d6 RW	466	.open = snapshot_open,
	467	.release = snapshot_release,
	468	.read = snapshot_read,
	469	.write = snapshot_write,
	470	.llseek = no_llseek,
	471	.ioctl = snapshot_ioctl,
	472	};
	473
	474	static struct miscdevice snapshot_device = {
	475	.minor = SNAPSHOT_MINOR,
	476	.name = "snapshot",
	477	.fops = &snapshot_fops,
	478	};
	479
	480	static int __init snapshot_device_init(void)
	481	{
	482	return misc_register(&snapshot_device);
	483	};
	484
	485	device_initcall(snapshot_device_init);