1 files changed, 443 insertions, 0 deletions

diff --git a/kernel/power/user.c b/kernel/power/user.c
new file mode 100644
index 0000000..005b93d
--- /dev/null
+++ b/kernel/power/user.c
@@ -0,0 +1,443 @@
+/*
+ * 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 = 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);