[mirror_ubuntu-bionic-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_RESTORE_PREPARE);
		if (error)
			pm_notifier_call_chain(PM_POST_RESTORE);
	} else {
		data->swap = -1;
		data->mode = O_WRONLY;
		error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
		if (error)
			pm_notifier_call_chain(PM_POST_HIBERNATION);
	}
	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 = freeze_processes();
		if (error)
			thaw_processes();
		if (!error)
			data->frozen = 1;
		break;

	case SNAPSHOT_UNFREEZE:
		if (!data->frozen || data->ready)
			break;
		thaw_processes();
		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;
c3e94d89 AS	98	error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
	99	if (error)
	100	pm_notifier_call_chain(PM_POST_RESTORE);
6e1819d6 RW	101	} else {
	102	data->swap = -1;
	103	data->mode = O_WRONLY;
c3e94d89 AS	104	error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
	105	if (error)
	106	pm_notifier_call_chain(PM_POST_HIBERNATION);
	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;
c3e94d89 AS	215	printk("Syncing filesystems ... ");
	216	sys_sync();
	217	printk("done.\n");
	218
	219	error = freeze_processes();
b10d9117	220	if (error)
c3e94d89	221	thaw_processes();
6e1819d6 RW	222	if (!error)
	223	data->frozen = 1;
	224	break;
	225
	226	case SNAPSHOT_UNFREEZE:
2f41dddb	227	if (!data->frozen \|\| data->ready)
6e1819d6	228	break;
6e1819d6	229	thaw_processes();
6e1819d6 RW	230	data->frozen = 0;
	231	break;
	232
cc5d207c	233	case SNAPSHOT_CREATE_IMAGE:
6e1819d6 RW	234	case SNAPSHOT_ATOMIC_SNAPSHOT:
	235	if (data->mode != O_RDONLY \|\| !data->frozen \|\| data->ready) {
	236	error = -EPERM;
	237	break;
	238	}
eb57c1cf	239	error = hibernation_snapshot(data->platform_support);
6e1819d6	240	if (!error)
cc5d207c	241	error = put_user(in_suspend, (int __user *)arg);
6e1819d6 RW	242	if (!error)
	243	data->ready = 1;
	244	break;
	245
	246	case SNAPSHOT_ATOMIC_RESTORE:
8357376d	247	snapshot_write_finalize(&data->handle);
6e1819d6 RW	248	if (data->mode != O_WRONLY \|\| !data->frozen \|\|
	249	!snapshot_image_loaded(&data->handle)) {
	250	error = -EPERM;
	251	break;
	252	}
eb57c1cf	253	error = hibernation_restore(data->platform_support);
6e1819d6 RW	254	break;
	255
	256	case SNAPSHOT_FREE:
	257	swsusp_free();
	258	memset(&data->handle, 0, sizeof(struct snapshot_handle));
	259	data->ready = 0;
	260	break;
	261
cc5d207c	262	case SNAPSHOT_PREF_IMAGE_SIZE:
6e1819d6 RW	263	case SNAPSHOT_SET_IMAGE_SIZE:
	264	image_size = arg;
	265	break;
	266
af508b34 RW	267	case SNAPSHOT_GET_IMAGE_SIZE:
	268	if (!data->ready) {
	269	error = -ENODATA;
	270	break;
	271	}
	272	size = snapshot_get_image_size();
	273	size <<= PAGE_SHIFT;
	274	error = put_user(size, (loff_t __user *)arg);
	275	break;
	276
cc5d207c	277	case SNAPSHOT_AVAIL_SWAP_SIZE:
6e1819d6	278	case SNAPSHOT_AVAIL_SWAP:
af508b34 RW	279	size = count_swap_pages(data->swap, 1);
	280	size <<= PAGE_SHIFT;
	281	error = put_user(size, (loff_t __user *)arg);
6e1819d6 RW	282	break;
6e1819d6 RW	283
cc5d207c	284	case SNAPSHOT_ALLOC_SWAP_PAGE:
6e1819d6 RW	285	case SNAPSHOT_GET_SWAP_PAGE:
	286	if (data->swap < 0 \|\| data->swap >= MAX_SWAPFILES) {
	287	error = -ENODEV;
	288	break;
	289	}
d1d241cc	290	offset = alloc_swapdev_block(data->swap);
6e1819d6 RW	291	if (offset) {
6e1819d6 RW	292	offset <<= PAGE_SHIFT;
cc5d207c	293	error = put_user(offset, (loff_t __user *)arg);
6e1819d6 RW	294	} else {
	295	error = -ENOSPC;
	296	}
	297	break;
	298
	299	case SNAPSHOT_FREE_SWAP_PAGES:
	300	if (data->swap < 0 \|\| data->swap >= MAX_SWAPFILES) {
	301	error = -ENODEV;
	302	break;
	303	}
d1d241cc	304	free_all_swap_pages(data->swap);
6e1819d6 RW	305	break;
6e1819d6 RW	306
96f73749	307	case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */
d1d241cc	308	if (!swsusp_swap_in_use()) {
6e1819d6 RW	309	/*
	310	* User space encodes device types as two-byte values,
	311	* so we need to recode them
	312	*/
	313	if (old_decode_dev(arg)) {
7bf23687 RW	314	data->swap = swap_type_of(old_decode_dev(arg),
7bf23687 RW	315	0, NULL);
6e1819d6 RW	316	if (data->swap < 0)
	317	error = -ENODEV;
	318	} else {
	319	data->swap = -1;
	320	error = -EINVAL;
	321	}
	322	} else {
	323	error = -EPERM;
	324	}
	325	break;
	326
9b238205 LT	327	case SNAPSHOT_S2RAM:
	328	if (!data->frozen) {
	329	error = -EPERM;
	330	break;
	331	}
6c961dfb RW	332	/*
	333	* Tasks are frozen and the notifiers have been called with
	334	* PM_HIBERNATION_PREPARE
	335	*/
	336	error = suspend_devices_and_enter(PM_SUSPEND_MEM);
9b238205 LT	337	break;
9b238205 LT	338
eb57c1cf RW	339	case SNAPSHOT_PLATFORM_SUPPORT:
	340	data->platform_support = !!arg;
	341	break;
	342
	343	case SNAPSHOT_POWER_OFF:
	344	if (data->platform_support)
	345	error = hibernation_platform_enter();
	346	break;
	347
	348	case SNAPSHOT_PMOPS: /* This ioctl is deprecated */
2b5b09b3 RW	349	error = -EINVAL;
2b5b09b3 RW	350
3592695c SS	351	switch (arg) {
	352
	353	case PMOPS_PREPARE:
eb57c1cf	354	data->platform_support = 1;
7777fab9	355	error = 0;
3592695c SS	356	break;
	357
	358	case PMOPS_ENTER:
eb57c1cf	359	if (data->platform_support)
7777fab9	360	error = hibernation_platform_enter();
3592695c SS	361	break;
	362
	363	case PMOPS_FINISH:
eb57c1cf	364	if (data->platform_support)
2b5b09b3	365	error = 0;
3592695c SS	366	break;
	367
	368	default:
	369	printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg);
3592695c SS	370
	371	}
	372	break;
	373
37b2ba12	374	case SNAPSHOT_SET_SWAP_AREA:
d1d241cc	375	if (swsusp_swap_in_use()) {
37b2ba12 RW	376	error = -EPERM;
	377	} else {
	378	struct resume_swap_area swap_area;
	379	dev_t swdev;
	380
	381	error = copy_from_user(&swap_area, (void __user *)arg,
	382	sizeof(struct resume_swap_area));
	383	if (error) {
	384	error = -EFAULT;
	385	break;
	386	}
	387
	388	/*
	389	* User space encodes device types as two-byte values,
	390	* so we need to recode them
	391	*/
	392	swdev = old_decode_dev(swap_area.dev);
	393	if (swdev) {
	394	offset = swap_area.offset;
7bf23687	395	data->swap = swap_type_of(swdev, offset, NULL);
37b2ba12 RW	396	if (data->swap < 0)
	397	error = -ENODEV;
	398	} else {
	399	data->swap = -1;
	400	error = -EINVAL;
	401	}
	402	}
	403	break;
	404
6e1819d6 RW	405	default:
	406	error = -ENOTTY;
	407
	408	}
25f2f3da RW	409
	410	mutex_unlock(&pm_mutex);
	411
6e1819d6 RW	412	return error;
	413	}
	414
15ad7cdc	415	static const struct file_operations snapshot_fops = {
6e1819d6 RW	416	.open = snapshot_open,
	417	.release = snapshot_release,
	418	.read = snapshot_read,
	419	.write = snapshot_write,
	420	.llseek = no_llseek,
52d11025	421	.unlocked_ioctl = snapshot_ioctl,
6e1819d6 RW	422	};
	423
	424	static struct miscdevice snapshot_device = {
	425	.minor = SNAPSHOT_MINOR,
	426	.name = "snapshot",
	427	.fops = &snapshot_fops,
	428	};
	429
	430	static int __init snapshot_device_init(void)
	431	{
	432	return misc_register(&snapshot_device);
	433	};
	434
	435	device_initcall(snapshot_device_init);