[deliverable/linux.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;

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