[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 <scsi/scsi_scan.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) {
		/* Hibernating.  The image device should be accessible. */
		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 {
		/*
		 * Resuming.  We may need to wait for the image device to
		 * appear.
		 */
		wait_for_device_probe();
		scsi_complete_async_scans();

		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>
c7510859	27	#include <scsi/scsi_scan.h>
6e1819d6 RW	28
	29	#include <asm/uaccess.h>
	30
	31	#include "power.h"
	32
eb57c1cf	33	/*
96f73749 RW	34	* NOTE: The SNAPSHOT_SET_SWAP_FILE and SNAPSHOT_PMOPS ioctls are obsolete and
	35	* will be removed in the future. They are only preserved here for
	36	* compatibility with existing userland utilities.
eb57c1cf	37	*/
96f73749	38	#define SNAPSHOT_SET_SWAP_FILE _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
eb57c1cf RW	39	#define SNAPSHOT_PMOPS _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
	40
	41	#define PMOPS_PREPARE 1
	42	#define PMOPS_ENTER 2
	43	#define PMOPS_FINISH 3
	44
cc5d207c RW	45	/*
	46	* NOTE: The following ioctl definitions are wrong and have been replaced with
	47	* correct ones. They are only preserved here for compatibility with existing
	48	* userland utilities and will be removed in the future.
	49	*/
	50	#define SNAPSHOT_ATOMIC_SNAPSHOT _IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
	51	#define SNAPSHOT_SET_IMAGE_SIZE _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
	52	#define SNAPSHOT_AVAIL_SWAP _IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
	53	#define SNAPSHOT_GET_SWAP_PAGE _IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
	54
eb57c1cf	55
6e1819d6 RW	56	#define SNAPSHOT_MINOR 231
	57
	58	static struct snapshot_data {
	59	struct snapshot_handle handle;
	60	int swap;
6e1819d6 RW	61	int mode;
	62	char frozen;
	63	char ready;
eb57c1cf	64	char platform_support;
6e1819d6 RW	65	} snapshot_state;
6e1819d6 RW	66
0709db60	67	atomic_t snapshot_device_available = ATOMIC_INIT(1);
6e1819d6 RW	68
	69	static int snapshot_open(struct inode inode, struct file filp)
	70	{
	71	struct snapshot_data *data;
c3e94d89	72	int error;
6e1819d6	73
25f2f3da RW	74	mutex_lock(&pm_mutex);
	75
	76	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
	77	error = -EBUSY;
	78	goto Unlock;
	79	}
6e1819d6	80
1525a2ad	81	if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
0709db60	82	atomic_inc(&snapshot_device_available);
25f2f3da RW	83	error = -ENOSYS;
25f2f3da RW	84	goto Unlock;
1525a2ad RW	85	}
1525a2ad RW	86	if(create_basic_memory_bitmaps()) {
0709db60	87	atomic_inc(&snapshot_device_available);
25f2f3da RW	88	error = -ENOMEM;
25f2f3da RW	89	goto Unlock;
1525a2ad	90	}
6e1819d6 RW	91	nonseekable_open(inode, filp);
	92	data = &snapshot_state;
	93	filp->private_data = data;
	94	memset(&data->handle, 0, sizeof(struct snapshot_handle));
	95	if ((filp->f_flags & O_ACCMODE) == O_RDONLY) {
c7510859	96	/* Hibernating. The image device should be accessible. */
915bae9e	97	data->swap = swsusp_resume_device ?
7bf23687	98	swap_type_of(swsusp_resume_device, 0, NULL) : -1;
6e1819d6	99	data->mode = O_RDONLY;
ebae2604	100	error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
c3e94d89	101	if (error)
ebae2604	102	pm_notifier_call_chain(PM_POST_HIBERNATION);
6e1819d6	103	} else {
c7510859 RW	104	/*
	105	* Resuming. We may need to wait for the image device to
	106	* appear.
	107	*/
	108	wait_for_device_probe();
	109	scsi_complete_async_scans();
	110
6e1819d6 RW	111	data->swap = -1;
6e1819d6 RW	112	data->mode = O_WRONLY;
ebae2604	113	error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
c3e94d89	114	if (error)
ebae2604	115	pm_notifier_call_chain(PM_POST_RESTORE);
c3e94d89	116	}
25f2f3da	117	if (error)
c3e94d89	118	atomic_inc(&snapshot_device_available);
6e1819d6 RW	119	data->frozen = 0;
6e1819d6 RW	120	data->ready = 0;
eb57c1cf	121	data->platform_support = 0;
6e1819d6	122
25f2f3da RW	123	Unlock:
	124	mutex_unlock(&pm_mutex);
	125
	126	return error;
6e1819d6 RW	127	}
	128
	129	static int snapshot_release(struct inode inode, struct file filp)
	130	{
	131	struct snapshot_data *data;
	132
25f2f3da RW	133	mutex_lock(&pm_mutex);
25f2f3da RW	134
6e1819d6	135	swsusp_free();
74dfd666	136	free_basic_memory_bitmaps();
6e1819d6	137	data = filp->private_data;
d1d241cc	138	free_all_swap_pages(data->swap);
25f2f3da	139	if (data->frozen)
6e1819d6	140	thaw_processes();
c3e94d89 AS	141	pm_notifier_call_chain(data->mode == O_WRONLY ?
c3e94d89 AS	142	PM_POST_HIBERNATION : PM_POST_RESTORE);
0709db60	143	atomic_inc(&snapshot_device_available);
25f2f3da RW	144
	145	mutex_unlock(&pm_mutex);
	146
6e1819d6 RW	147	return 0;
	148	}
	149
	150	static ssize_t snapshot_read(struct file filp, char __user buf,
	151	size_t count, loff_t *offp)
	152	{
	153	struct snapshot_data *data;
	154	ssize_t res;
	155
25f2f3da RW	156	mutex_lock(&pm_mutex);
25f2f3da RW	157
6e1819d6	158	data = filp->private_data;
25f2f3da RW	159	if (!data->ready) {
	160	res = -ENODATA;
	161	goto Unlock;
	162	}
6e1819d6 RW	163	res = snapshot_read_next(&data->handle, count);
	164	if (res > 0) {
	165	if (copy_to_user(buf, data_of(data->handle), res))
	166	res = -EFAULT;
	167	else
	168	*offp = data->handle.offset;
	169	}
25f2f3da RW	170
	171	Unlock:
	172	mutex_unlock(&pm_mutex);
	173
6e1819d6 RW	174	return res;
	175	}
	176
	177	static ssize_t snapshot_write(struct file filp, const char __user buf,
	178	size_t count, loff_t *offp)
	179	{
	180	struct snapshot_data *data;
	181	ssize_t res;
	182
25f2f3da RW	183	mutex_lock(&pm_mutex);
25f2f3da RW	184
6e1819d6 RW	185	data = filp->private_data;
	186	res = snapshot_write_next(&data->handle, count);
	187	if (res > 0) {
	188	if (copy_from_user(data_of(data->handle), buf, res))
	189	res = -EFAULT;
	190	else
	191	*offp = data->handle.offset;
	192	}
25f2f3da RW	193
	194	mutex_unlock(&pm_mutex);
	195
6e1819d6 RW	196	return res;
	197	}
	198
52d11025 AC	199	static long snapshot_ioctl(struct file *filp, unsigned int cmd,
52d11025 AC	200	unsigned long arg)
6e1819d6 RW	201	{
	202	int error = 0;
	203	struct snapshot_data *data;
af508b34	204	loff_t size;
3aef83e0	205	sector_t offset;
6e1819d6 RW	206
	207	if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
	208	return -ENOTTY;
	209	if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR)
	210	return -ENOTTY;
	211	if (!capable(CAP_SYS_ADMIN))
	212	return -EPERM;
	213
25f2f3da RW	214	if (!mutex_trylock(&pm_mutex))
25f2f3da RW	215	return -EBUSY;
6e1819d6	216
25f2f3da	217	data = filp->private_data;
52d11025	218
6e1819d6 RW	219	switch (cmd) {
	220
	221	case SNAPSHOT_FREEZE:
	222	if (data->frozen)
	223	break;
1bfcf130	224
c3e94d89 AS	225	printk("Syncing filesystems ... ");
	226	sys_sync();
	227	printk("done.\n");
	228
1bfcf130	229	error = usermodehelper_disable();
b10d9117	230	if (error)
1bfcf130 RW	231	break;
	232
	233	error = freeze_processes();
	234	if (error) {
c3e94d89	235	thaw_processes();
1bfcf130 RW	236	usermodehelper_enable();
1bfcf130 RW	237	}
6e1819d6 RW	238	if (!error)
	239	data->frozen = 1;
	240	break;
	241
	242	case SNAPSHOT_UNFREEZE:
2f41dddb	243	if (!data->frozen \|\| data->ready)
6e1819d6	244	break;
6e1819d6	245	thaw_processes();
1bfcf130	246	usermodehelper_enable();
6e1819d6 RW	247	data->frozen = 0;
	248	break;
	249
cc5d207c	250	case SNAPSHOT_CREATE_IMAGE:
6e1819d6 RW	251	case SNAPSHOT_ATOMIC_SNAPSHOT:
	252	if (data->mode != O_RDONLY \|\| !data->frozen \|\| data->ready) {
	253	error = -EPERM;
	254	break;
	255	}
eb57c1cf	256	error = hibernation_snapshot(data->platform_support);
6e1819d6	257	if (!error)
cc5d207c	258	error = put_user(in_suspend, (int __user *)arg);
6e1819d6 RW	259	if (!error)
	260	data->ready = 1;
	261	break;
	262
	263	case SNAPSHOT_ATOMIC_RESTORE:
8357376d	264	snapshot_write_finalize(&data->handle);
6e1819d6 RW	265	if (data->mode != O_WRONLY \|\| !data->frozen \|\|
	266	!snapshot_image_loaded(&data->handle)) {
	267	error = -EPERM;
	268	break;
	269	}
eb57c1cf	270	error = hibernation_restore(data->platform_support);
6e1819d6 RW	271	break;
	272
	273	case SNAPSHOT_FREE:
	274	swsusp_free();
	275	memset(&data->handle, 0, sizeof(struct snapshot_handle));
	276	data->ready = 0;
	277	break;
	278
cc5d207c	279	case SNAPSHOT_PREF_IMAGE_SIZE:
6e1819d6 RW	280	case SNAPSHOT_SET_IMAGE_SIZE:
	281	image_size = arg;
	282	break;
	283
af508b34 RW	284	case SNAPSHOT_GET_IMAGE_SIZE:
	285	if (!data->ready) {
	286	error = -ENODATA;
	287	break;
	288	}
	289	size = snapshot_get_image_size();
	290	size <<= PAGE_SHIFT;
	291	error = put_user(size, (loff_t __user *)arg);
	292	break;
	293
cc5d207c	294	case SNAPSHOT_AVAIL_SWAP_SIZE:
6e1819d6	295	case SNAPSHOT_AVAIL_SWAP:
af508b34 RW	296	size = count_swap_pages(data->swap, 1);
	297	size <<= PAGE_SHIFT;
	298	error = put_user(size, (loff_t __user *)arg);
6e1819d6 RW	299	break;
6e1819d6 RW	300
cc5d207c	301	case SNAPSHOT_ALLOC_SWAP_PAGE:
6e1819d6 RW	302	case SNAPSHOT_GET_SWAP_PAGE:
	303	if (data->swap < 0 \|\| data->swap >= MAX_SWAPFILES) {
	304	error = -ENODEV;
	305	break;
	306	}
d1d241cc	307	offset = alloc_swapdev_block(data->swap);
6e1819d6 RW	308	if (offset) {
6e1819d6 RW	309	offset <<= PAGE_SHIFT;
cc5d207c	310	error = put_user(offset, (loff_t __user *)arg);
6e1819d6 RW	311	} else {
	312	error = -ENOSPC;
	313	}
	314	break;
	315
	316	case SNAPSHOT_FREE_SWAP_PAGES:
	317	if (data->swap < 0 \|\| data->swap >= MAX_SWAPFILES) {
	318	error = -ENODEV;
	319	break;
	320	}
d1d241cc	321	free_all_swap_pages(data->swap);
6e1819d6 RW	322	break;
6e1819d6 RW	323
96f73749	324	case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */
d1d241cc	325	if (!swsusp_swap_in_use()) {
6e1819d6 RW	326	/*
	327	* User space encodes device types as two-byte values,
	328	* so we need to recode them
	329	*/
	330	if (old_decode_dev(arg)) {
7bf23687 RW	331	data->swap = swap_type_of(old_decode_dev(arg),
7bf23687 RW	332	0, NULL);
6e1819d6 RW	333	if (data->swap < 0)
	334	error = -ENODEV;
	335	} else {
	336	data->swap = -1;
	337	error = -EINVAL;
	338	}
	339	} else {
	340	error = -EPERM;
	341	}
	342	break;
	343
9b238205 LT	344	case SNAPSHOT_S2RAM:
	345	if (!data->frozen) {
	346	error = -EPERM;
	347	break;
	348	}
6c961dfb RW	349	/*
	350	* Tasks are frozen and the notifiers have been called with
	351	* PM_HIBERNATION_PREPARE
	352	*/
	353	error = suspend_devices_and_enter(PM_SUSPEND_MEM);
9b238205 LT	354	break;
9b238205 LT	355
eb57c1cf RW	356	case SNAPSHOT_PLATFORM_SUPPORT:
	357	data->platform_support = !!arg;
	358	break;
	359
	360	case SNAPSHOT_POWER_OFF:
	361	if (data->platform_support)
	362	error = hibernation_platform_enter();
	363	break;
	364
	365	case SNAPSHOT_PMOPS: /* This ioctl is deprecated */
2b5b09b3 RW	366	error = -EINVAL;
2b5b09b3 RW	367
3592695c SS	368	switch (arg) {
	369
	370	case PMOPS_PREPARE:
eb57c1cf	371	data->platform_support = 1;
7777fab9	372	error = 0;
3592695c SS	373	break;
	374
	375	case PMOPS_ENTER:
eb57c1cf	376	if (data->platform_support)
7777fab9	377	error = hibernation_platform_enter();
3592695c SS	378	break;
	379
	380	case PMOPS_FINISH:
eb57c1cf	381	if (data->platform_support)
2b5b09b3	382	error = 0;
3592695c SS	383	break;
	384
	385	default:
	386	printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg);
3592695c SS	387
	388	}
	389	break;
	390
37b2ba12	391	case SNAPSHOT_SET_SWAP_AREA:
d1d241cc	392	if (swsusp_swap_in_use()) {
37b2ba12 RW	393	error = -EPERM;
	394	} else {
	395	struct resume_swap_area swap_area;
	396	dev_t swdev;
	397
	398	error = copy_from_user(&swap_area, (void __user *)arg,
	399	sizeof(struct resume_swap_area));
	400	if (error) {
	401	error = -EFAULT;
	402	break;
	403	}
	404
	405	/*
	406	* User space encodes device types as two-byte values,
	407	* so we need to recode them
	408	*/
	409	swdev = old_decode_dev(swap_area.dev);
	410	if (swdev) {
	411	offset = swap_area.offset;
7bf23687	412	data->swap = swap_type_of(swdev, offset, NULL);
37b2ba12 RW	413	if (data->swap < 0)
	414	error = -ENODEV;
	415	} else {
	416	data->swap = -1;
	417	error = -EINVAL;
	418	}
	419	}
	420	break;
	421
6e1819d6 RW	422	default:
	423	error = -ENOTTY;
	424
	425	}
25f2f3da RW	426
	427	mutex_unlock(&pm_mutex);
	428
6e1819d6 RW	429	return error;
	430	}
	431
15ad7cdc	432	static const struct file_operations snapshot_fops = {
6e1819d6 RW	433	.open = snapshot_open,
	434	.release = snapshot_release,
	435	.read = snapshot_read,
	436	.write = snapshot_write,
	437	.llseek = no_llseek,
52d11025	438	.unlocked_ioctl = snapshot_ioctl,
6e1819d6 RW	439	};
	440
	441	static struct miscdevice snapshot_device = {
	442	.minor = SNAPSHOT_MINOR,
	443	.name = "snapshot",
	444	.fops = &snapshot_fops,
	445	};
	446
	447	static int __init snapshot_device_init(void)
	448	{
	449	return misc_register(&snapshot_device);
	450	};
	451
	452	device_initcall(snapshot_device_init);