[mirror_ubuntu-artful-kernel.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 <linux/smp_lock.h>

#include <asm/uaccess.h>

#include "power.h"

/*
 * NOTE: The SNAPSHOT_SET_SWAP_FILE and SNAPSHOT_PMOPS ioctls are obsolete and
 * will be removed in the future.  They are only preserved here for
 * compatibility with existing userland utilities.
 */
#define SNAPSHOT_SET_SWAP_FILE	_IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
#define SNAPSHOT_PMOPS		_IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)

#define PMOPS_PREPARE	1
#define PMOPS_ENTER	2
#define PMOPS_FINISH	3

/*
 * NOTE: The following ioctl definitions are wrong and have been replaced with
 * correct ones.  They are only preserved here for compatibility with existing
 * userland utilities and will be removed in the future.
 */
#define SNAPSHOT_ATOMIC_SNAPSHOT	_IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
#define SNAPSHOT_SET_IMAGE_SIZE		_IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
#define SNAPSHOT_AVAIL_SWAP		_IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
#define SNAPSHOT_GET_SWAP_PAGE		_IOR(SNAPSHOT_IOC_MAGIC, 8, void *)


#define SNAPSHOT_MINOR	231

static struct snapshot_data {
	struct snapshot_handle handle;
	int swap;
	int mode;
	char frozen;
	char ready;
	char platform_support;
} snapshot_state;

atomic_t snapshot_device_available = ATOMIC_INIT(1);

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

	mutex_lock(&pm_mutex);

	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) {
		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 {
		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)
		atomic_inc(&snapshot_device_available);
	data->frozen = 0;
	data->ready = 0;
	data->platform_support = 0;

 Unlock:
	mutex_unlock(&pm_mutex);

	return error;
}

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;
}

static ssize_t snapshot_read(struct file *filp, char __user *buf,
                             size_t count, loff_t *offp)
{
	struct snapshot_data *data;
	ssize_t res;

	mutex_lock(&pm_mutex);

	data = filp->private_data;
	if (!data->ready) {
		res = -ENODATA;
		goto Unlock;
	}
	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;
	}

 Unlock:
	mutex_unlock(&pm_mutex);

	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;

	mutex_lock(&pm_mutex);

	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;
	}

	mutex_unlock(&pm_mutex);

	return res;
}

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;

	data = filp->private_data;

	switch (cmd) {

	case SNAPSHOT_FREEZE:
		if (data->frozen)
			break;

		printk("Syncing filesystems ... ");
		sys_sync();
		printk("done.\n");

		error = usermodehelper_disable();
		if (error)
			break;

		error = freeze_processes();
		if (error) {
			thaw_processes();
			usermodehelper_enable();
		}
		if (!error)
			data->frozen = 1;
		break;

	case SNAPSHOT_UNFREEZE:
		if (!data->frozen || data->ready)
			break;
		thaw_processes();
		usermodehelper_enable();
		data->frozen = 0;
		break;

	case SNAPSHOT_CREATE_IMAGE:
	case SNAPSHOT_ATOMIC_SNAPSHOT:
		if (data->mode != O_RDONLY || !data->frozen  || data->ready) {
			error = -EPERM;
			break;
		}
		error = hibernation_snapshot(data->platform_support);
		if (!error)
			error = put_user(in_suspend, (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 = hibernation_restore(data->platform_support);
		break;

	case SNAPSHOT_FREE:
		swsusp_free();
		memset(&data->handle, 0, sizeof(struct snapshot_handle));
		data->ready = 0;
		break;

	case SNAPSHOT_PREF_IMAGE_SIZE:
	case SNAPSHOT_SET_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:
	case SNAPSHOT_AVAIL_SWAP:
		size = count_swap_pages(data->swap, 1);
		size <<= PAGE_SHIFT;
		error = put_user(size, (loff_t __user *)arg);
		break;

	case SNAPSHOT_ALLOC_SWAP_PAGE:
	case SNAPSHOT_GET_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_SET_SWAP_FILE: /* This ioctl is deprecated */
		if (!swsusp_swap_in_use()) {
			/*
			 * 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 (!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);
		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_PMOPS: /* This ioctl is deprecated */
		error = -EINVAL;

		switch (arg) {

		case PMOPS_PREPARE:
			data->platform_support = 1;
			error = 0;
			break;

		case PMOPS_ENTER:
			if (data->platform_support)
				error = hibernation_platform_enter();
			break;

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

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

		}
		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 = 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;

	}

	mutex_unlock(&pm_mutex);

	return error;
}

static const struct file_operations snapshot_fops = {
	.open = snapshot_open,
	.release = snapshot_release,
	.read = snapshot_read,
	.write = snapshot_write,
	.llseek = no_llseek,
	.unlocked_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>
52d11025	26	#include <linux/smp_lock.h>
6e1819d6 RW	27
	28	#include <asm/uaccess.h>
	29
	30	#include "power.h"
	31
eb57c1cf	32	/*
96f73749 RW	33	* NOTE: The SNAPSHOT_SET_SWAP_FILE and SNAPSHOT_PMOPS ioctls are obsolete and
	34	* will be removed in the future. They are only preserved here for
	35	* compatibility with existing userland utilities.
eb57c1cf	36	*/
96f73749	37	#define SNAPSHOT_SET_SWAP_FILE _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
eb57c1cf RW	38	#define SNAPSHOT_PMOPS _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
	39
	40	#define PMOPS_PREPARE 1
	41	#define PMOPS_ENTER 2
	42	#define PMOPS_FINISH 3
	43
cc5d207c RW	44	/*
	45	* NOTE: The following ioctl definitions are wrong and have been replaced with
	46	* correct ones. They are only preserved here for compatibility with existing
	47	* userland utilities and will be removed in the future.
	48	*/
	49	#define SNAPSHOT_ATOMIC_SNAPSHOT _IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
	50	#define SNAPSHOT_SET_IMAGE_SIZE _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
	51	#define SNAPSHOT_AVAIL_SWAP _IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
	52	#define SNAPSHOT_GET_SWAP_PAGE _IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
	53
eb57c1cf	54
6e1819d6 RW	55	#define SNAPSHOT_MINOR 231
	56
	57	static struct snapshot_data {
	58	struct snapshot_handle handle;
	59	int swap;
6e1819d6 RW	60	int mode;
	61	char frozen;
	62	char ready;
eb57c1cf	63	char platform_support;
6e1819d6 RW	64	} snapshot_state;
6e1819d6 RW	65
0709db60	66	atomic_t snapshot_device_available = ATOMIC_INIT(1);
6e1819d6 RW	67
	68	static int snapshot_open(struct inode inode, struct file filp)
	69	{
	70	struct snapshot_data *data;
c3e94d89	71	int error;
6e1819d6	72
25f2f3da RW	73	mutex_lock(&pm_mutex);
	74
	75	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
	76	error = -EBUSY;
	77	goto Unlock;
	78	}
6e1819d6	79
1525a2ad	80	if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
0709db60	81	atomic_inc(&snapshot_device_available);
25f2f3da RW	82	error = -ENOSYS;
25f2f3da RW	83	goto Unlock;
1525a2ad RW	84	}
1525a2ad RW	85	if(create_basic_memory_bitmaps()) {
0709db60	86	atomic_inc(&snapshot_device_available);
25f2f3da RW	87	error = -ENOMEM;
25f2f3da RW	88	goto Unlock;
1525a2ad	89	}
6e1819d6 RW	90	nonseekable_open(inode, filp);
	91	data = &snapshot_state;
	92	filp->private_data = data;
	93	memset(&data->handle, 0, sizeof(struct snapshot_handle));
	94	if ((filp->f_flags & O_ACCMODE) == O_RDONLY) {
915bae9e	95	data->swap = swsusp_resume_device ?
7bf23687	96	swap_type_of(swsusp_resume_device, 0, NULL) : -1;
6e1819d6	97	data->mode = O_RDONLY;
ebae2604	98	error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
c3e94d89	99	if (error)
ebae2604	100	pm_notifier_call_chain(PM_POST_HIBERNATION);
6e1819d6 RW	101	} else {
	102	data->swap = -1;
	103	data->mode = O_WRONLY;
ebae2604	104	error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
c3e94d89	105	if (error)
ebae2604	106	pm_notifier_call_chain(PM_POST_RESTORE);
c3e94d89	107	}
25f2f3da	108	if (error)
c3e94d89	109	atomic_inc(&snapshot_device_available);
6e1819d6 RW	110	data->frozen = 0;
6e1819d6 RW	111	data->ready = 0;
eb57c1cf	112	data->platform_support = 0;
6e1819d6	113
25f2f3da RW	114	Unlock:
	115	mutex_unlock(&pm_mutex);
	116
	117	return error;
6e1819d6 RW	118	}
	119
	120	static int snapshot_release(struct inode inode, struct file filp)
	121	{
	122	struct snapshot_data *data;
	123
25f2f3da RW	124	mutex_lock(&pm_mutex);
25f2f3da RW	125
6e1819d6	126	swsusp_free();
74dfd666	127	free_basic_memory_bitmaps();
6e1819d6	128	data = filp->private_data;
d1d241cc	129	free_all_swap_pages(data->swap);
25f2f3da	130	if (data->frozen)
6e1819d6	131	thaw_processes();
c3e94d89 AS	132	pm_notifier_call_chain(data->mode == O_WRONLY ?
c3e94d89 AS	133	PM_POST_HIBERNATION : PM_POST_RESTORE);
0709db60	134	atomic_inc(&snapshot_device_available);
25f2f3da RW	135
	136	mutex_unlock(&pm_mutex);
	137
6e1819d6 RW	138	return 0;
	139	}
	140
	141	static ssize_t snapshot_read(struct file filp, char __user buf,
	142	size_t count, loff_t *offp)
	143	{
	144	struct snapshot_data *data;
	145	ssize_t res;
	146
25f2f3da RW	147	mutex_lock(&pm_mutex);
25f2f3da RW	148
6e1819d6	149	data = filp->private_data;
25f2f3da RW	150	if (!data->ready) {
	151	res = -ENODATA;
	152	goto Unlock;
	153	}
6e1819d6 RW	154	res = snapshot_read_next(&data->handle, count);
	155	if (res > 0) {
	156	if (copy_to_user(buf, data_of(data->handle), res))
	157	res = -EFAULT;
	158	else
	159	*offp = data->handle.offset;
	160	}
25f2f3da RW	161
	162	Unlock:
	163	mutex_unlock(&pm_mutex);
	164
6e1819d6 RW	165	return res;
	166	}
	167
	168	static ssize_t snapshot_write(struct file filp, const char __user buf,
	169	size_t count, loff_t *offp)
	170	{
	171	struct snapshot_data *data;
	172	ssize_t res;
	173
25f2f3da RW	174	mutex_lock(&pm_mutex);
25f2f3da RW	175
6e1819d6 RW	176	data = filp->private_data;
	177	res = snapshot_write_next(&data->handle, count);
	178	if (res > 0) {
	179	if (copy_from_user(data_of(data->handle), buf, res))
	180	res = -EFAULT;
	181	else
	182	*offp = data->handle.offset;
	183	}
25f2f3da RW	184
	185	mutex_unlock(&pm_mutex);
	186
6e1819d6 RW	187	return res;
	188	}
	189
52d11025 AC	190	static long snapshot_ioctl(struct file *filp, unsigned int cmd,
52d11025 AC	191	unsigned long arg)
6e1819d6 RW	192	{
	193	int error = 0;
	194	struct snapshot_data *data;
af508b34	195	loff_t size;
3aef83e0	196	sector_t offset;
6e1819d6 RW	197
	198	if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
	199	return -ENOTTY;
	200	if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR)
	201	return -ENOTTY;
	202	if (!capable(CAP_SYS_ADMIN))
	203	return -EPERM;
	204
25f2f3da RW	205	if (!mutex_trylock(&pm_mutex))
25f2f3da RW	206	return -EBUSY;
6e1819d6	207
25f2f3da	208	data = filp->private_data;
52d11025	209
6e1819d6 RW	210	switch (cmd) {
	211
	212	case SNAPSHOT_FREEZE:
	213	if (data->frozen)
	214	break;
1bfcf130	215
c3e94d89 AS	216	printk("Syncing filesystems ... ");
	217	sys_sync();
	218	printk("done.\n");
	219
1bfcf130	220	error = usermodehelper_disable();
b10d9117	221	if (error)
1bfcf130 RW	222	break;
	223
	224	error = freeze_processes();
	225	if (error) {
c3e94d89	226	thaw_processes();
1bfcf130 RW	227	usermodehelper_enable();
1bfcf130 RW	228	}
6e1819d6 RW	229	if (!error)
	230	data->frozen = 1;
	231	break;
	232
	233	case SNAPSHOT_UNFREEZE:
2f41dddb	234	if (!data->frozen \|\| data->ready)
6e1819d6	235	break;
6e1819d6	236	thaw_processes();
1bfcf130	237	usermodehelper_enable();
6e1819d6 RW	238	data->frozen = 0;
	239	break;
	240
cc5d207c	241	case SNAPSHOT_CREATE_IMAGE:
6e1819d6 RW	242	case SNAPSHOT_ATOMIC_SNAPSHOT:
	243	if (data->mode != O_RDONLY \|\| !data->frozen \|\| data->ready) {
	244	error = -EPERM;
	245	break;
	246	}
eb57c1cf	247	error = hibernation_snapshot(data->platform_support);
6e1819d6	248	if (!error)
cc5d207c	249	error = put_user(in_suspend, (int __user *)arg);
6e1819d6 RW	250	if (!error)
	251	data->ready = 1;
	252	break;
	253
	254	case SNAPSHOT_ATOMIC_RESTORE:
8357376d	255	snapshot_write_finalize(&data->handle);
6e1819d6 RW	256	if (data->mode != O_WRONLY \|\| !data->frozen \|\|
	257	!snapshot_image_loaded(&data->handle)) {
	258	error = -EPERM;
	259	break;
	260	}
eb57c1cf	261	error = hibernation_restore(data->platform_support);
6e1819d6 RW	262	break;
	263
	264	case SNAPSHOT_FREE:
	265	swsusp_free();
	266	memset(&data->handle, 0, sizeof(struct snapshot_handle));
	267	data->ready = 0;
	268	break;
	269
cc5d207c	270	case SNAPSHOT_PREF_IMAGE_SIZE:
6e1819d6 RW	271	case SNAPSHOT_SET_IMAGE_SIZE:
	272	image_size = arg;
	273	break;
	274
af508b34 RW	275	case SNAPSHOT_GET_IMAGE_SIZE:
	276	if (!data->ready) {
	277	error = -ENODATA;
	278	break;
	279	}
	280	size = snapshot_get_image_size();
	281	size <<= PAGE_SHIFT;
	282	error = put_user(size, (loff_t __user *)arg);
	283	break;
	284
cc5d207c	285	case SNAPSHOT_AVAIL_SWAP_SIZE:
6e1819d6	286	case SNAPSHOT_AVAIL_SWAP:
af508b34 RW	287	size = count_swap_pages(data->swap, 1);
	288	size <<= PAGE_SHIFT;
	289	error = put_user(size, (loff_t __user *)arg);
6e1819d6 RW	290	break;
6e1819d6 RW	291
cc5d207c	292	case SNAPSHOT_ALLOC_SWAP_PAGE:
6e1819d6 RW	293	case SNAPSHOT_GET_SWAP_PAGE:
	294	if (data->swap < 0 \|\| data->swap >= MAX_SWAPFILES) {
	295	error = -ENODEV;
	296	break;
	297	}
d1d241cc	298	offset = alloc_swapdev_block(data->swap);
6e1819d6 RW	299	if (offset) {
6e1819d6 RW	300	offset <<= PAGE_SHIFT;
cc5d207c	301	error = put_user(offset, (loff_t __user *)arg);
6e1819d6 RW	302	} else {
	303	error = -ENOSPC;
	304	}
	305	break;
	306
	307	case SNAPSHOT_FREE_SWAP_PAGES:
	308	if (data->swap < 0 \|\| data->swap >= MAX_SWAPFILES) {
	309	error = -ENODEV;
	310	break;
	311	}
d1d241cc	312	free_all_swap_pages(data->swap);
6e1819d6 RW	313	break;
6e1819d6 RW	314
96f73749	315	case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */
d1d241cc	316	if (!swsusp_swap_in_use()) {
6e1819d6 RW	317	/*
	318	* User space encodes device types as two-byte values,
	319	* so we need to recode them
	320	*/
	321	if (old_decode_dev(arg)) {
7bf23687 RW	322	data->swap = swap_type_of(old_decode_dev(arg),
7bf23687 RW	323	0, NULL);
6e1819d6 RW	324	if (data->swap < 0)
	325	error = -ENODEV;
	326	} else {
	327	data->swap = -1;
	328	error = -EINVAL;
	329	}
	330	} else {
	331	error = -EPERM;
	332	}
	333	break;
	334
9b238205 LT	335	case SNAPSHOT_S2RAM:
	336	if (!data->frozen) {
	337	error = -EPERM;
	338	break;
	339	}
6c961dfb RW	340	/*
	341	* Tasks are frozen and the notifiers have been called with
	342	* PM_HIBERNATION_PREPARE
	343	*/
	344	error = suspend_devices_and_enter(PM_SUSPEND_MEM);
9b238205 LT	345	break;
9b238205 LT	346
eb57c1cf RW	347	case SNAPSHOT_PLATFORM_SUPPORT:
	348	data->platform_support = !!arg;
	349	break;
	350
	351	case SNAPSHOT_POWER_OFF:
	352	if (data->platform_support)
	353	error = hibernation_platform_enter();
	354	break;
	355
	356	case SNAPSHOT_PMOPS: /* This ioctl is deprecated */
2b5b09b3 RW	357	error = -EINVAL;
2b5b09b3 RW	358
3592695c SS	359	switch (arg) {
	360
	361	case PMOPS_PREPARE:
eb57c1cf	362	data->platform_support = 1;
7777fab9	363	error = 0;
3592695c SS	364	break;
	365
	366	case PMOPS_ENTER:
eb57c1cf	367	if (data->platform_support)
7777fab9	368	error = hibernation_platform_enter();
3592695c SS	369	break;
	370
	371	case PMOPS_FINISH:
eb57c1cf	372	if (data->platform_support)
2b5b09b3	373	error = 0;
3592695c SS	374	break;
	375
	376	default:
	377	printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg);
3592695c SS	378
	379	}
	380	break;
	381
37b2ba12	382	case SNAPSHOT_SET_SWAP_AREA:
d1d241cc	383	if (swsusp_swap_in_use()) {
37b2ba12 RW	384	error = -EPERM;
	385	} else {
	386	struct resume_swap_area swap_area;
	387	dev_t swdev;
	388
	389	error = copy_from_user(&swap_area, (void __user *)arg,
	390	sizeof(struct resume_swap_area));
	391	if (error) {
	392	error = -EFAULT;
	393	break;
	394	}
	395
	396	/*
	397	* User space encodes device types as two-byte values,
	398	* so we need to recode them
	399	*/
	400	swdev = old_decode_dev(swap_area.dev);
	401	if (swdev) {
	402	offset = swap_area.offset;
7bf23687	403	data->swap = swap_type_of(swdev, offset, NULL);
37b2ba12 RW	404	if (data->swap < 0)
	405	error = -ENODEV;
	406	} else {
	407	data->swap = -1;
	408	error = -EINVAL;
	409	}
	410	}
	411	break;
	412
6e1819d6 RW	413	default:
	414	error = -ENOTTY;
	415
	416	}
25f2f3da RW	417
	418	mutex_unlock(&pm_mutex);
	419
6e1819d6 RW	420	return error;
	421	}
	422
15ad7cdc	423	static const struct file_operations snapshot_fops = {
6e1819d6 RW	424	.open = snapshot_open,
	425	.release = snapshot_release,
	426	.read = snapshot_read,
	427	.write = snapshot_write,
	428	.llseek = no_llseek,
52d11025	429	.unlocked_ioctl = snapshot_ioctl,
6e1819d6 RW	430	};
	431
	432	static struct miscdevice snapshot_device = {
	433	.minor = SNAPSHOT_MINOR,
	434	.name = "snapshot",
	435	.fops = &snapshot_fops,
	436	};
	437
	438	static int __init snapshot_device_init(void)
	439	{
	440	return misc_register(&snapshot_device);
	441	};
	442
	443	device_initcall(snapshot_device_init);