Esempio n. 1
0
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;

	lock_device_hotplug();
	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)
			break;

		error = create_basic_memory_bitmaps();
		if (error)
			thaw_processes();
		else
			data->frozen = true;

		break;

	case SNAPSHOT_UNFREEZE:
		if (!data->frozen || data->ready)
			break;
		pm_restore_gfp_mask();
		free_basic_memory_bitmaps();
		data->free_bitmaps = false;
		thaw_processes();
		data->frozen = false;
		break;

	case SNAPSHOT_CREATE_IMAGE:
		if (data->mode != O_RDONLY || !data->frozen  || data->ready) {
			error = -EPERM;
			break;
		}
		pm_restore_gfp_mask();
		error = hibernation_snapshot(data->platform_support);
		if (!error) {
			error = put_user(in_suspend, (int __user *)arg);
			data->ready = !freezer_test_done && !error;
			freezer_test_done = false;
		}
		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 = false;
		/*
		 * It is necessary to thaw kernel threads here, because
		 * SNAPSHOT_CREATE_IMAGE may be invoked directly after
		 * SNAPSHOT_FREE.  In that case, if kernel threads were not
		 * thawed, the preallocation of memory carried out by
		 * hibernation_snapshot() might run into problems (i.e. it
		 * might fail or even deadlock).
		 */
		thaw_kernel_threads();
		break;

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

	case SNAPSHOT_ALLOC_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_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);
		data->ready = false;
		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_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 = new_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;

	}

	unlock_device_hotplug();
	mutex_unlock(&pm_mutex);

	return error;
}
Esempio n. 2
0
/**
 * software_resume - Resume from a saved hibernation image.
 *
 * This routine is called as a late initcall, when all devices have been
 * discovered and initialized already.
 *
 * The image reading code is called to see if there is a hibernation image
 * available for reading.  If that is the case, devices are quiesced and the
 * contents of memory is restored from the saved image.
 *
 * If this is successful, control reappears in the restored target kernel in
 * hibernation_snaphot() which returns to hibernate().  Otherwise, the routine
 * attempts to recover gracefully and make the kernel return to the normal mode
 * of operation.
 */
static int software_resume(void)
{
	int error;
	unsigned int flags;

	/*
	 * If the user said "noresume".. bail out early.
	 */
	if (noresume || !hibernation_available())
		return 0;

	/*
	 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
	 * is configured into the kernel. Since the regular hibernate
	 * trigger path is via sysfs which takes a buffer mutex before
	 * calling hibernate functions (which take pm_mutex) this can
	 * cause lockdep to complain about a possible ABBA deadlock
	 * which cannot happen since we're in the boot code here and
	 * sysfs can't be invoked yet. Therefore, we use a subclass
	 * here to avoid lockdep complaining.
	 */
	mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);

	if (swsusp_resume_device)
		goto Check_image;

	if (!strlen(resume_file)) {
		error = -ENOENT;
		goto Unlock;
	}

	pr_debug("PM: Checking hibernation image partition %s\n", resume_file);

	if (resume_delay) {
		printk(KERN_INFO "Waiting %dsec before reading resume device...\n",
			resume_delay);
		ssleep(resume_delay);
	}

	/* Check if the device is there */
	swsusp_resume_device = name_to_dev_t(resume_file);

	/*
	 * name_to_dev_t is ineffective to verify parition if resume_file is in
	 * integer format. (e.g. major:minor)
	 */
	if (isdigit(resume_file[0]) && resume_wait) {
		int partno;
		while (!get_gendisk(swsusp_resume_device, &partno))
			msleep(10);
	}

	if (!swsusp_resume_device) {
		/*
		 * Some device discovery might still be in progress; we need
		 * to wait for this to finish.
		 */
		wait_for_device_probe();

		if (resume_wait) {
			while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
				msleep(10);
			async_synchronize_full();
		}

		swsusp_resume_device = name_to_dev_t(resume_file);
		if (!swsusp_resume_device) {
			error = -ENODEV;
			goto Unlock;
		}
	}

 Check_image:
	pr_debug("PM: Hibernation image partition %d:%d present\n",
		MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));

	pr_debug("PM: Looking for hibernation image.\n");
	error = swsusp_check();
	if (error)
		goto Unlock;

	/* The snapshot device should not be opened while we're running */
	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
		error = -EBUSY;
		swsusp_close(FMODE_READ);
		goto Unlock;
	}

	pm_prepare_console();
	error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
	if (error)
		goto Close_Finish;

	pr_debug("PM: Preparing processes for restore.\n");
	error = freeze_processes();
	if (error)
		goto Close_Finish;

	pr_debug("PM: Loading hibernation image.\n");

	lock_device_hotplug();
	error = create_basic_memory_bitmaps();
	if (error)
		goto Thaw;

	error = swsusp_read(&flags);
	swsusp_close(FMODE_READ);
	if (!error)
		hibernation_restore(flags & SF_PLATFORM_MODE);

	printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
	swsusp_free();
	free_basic_memory_bitmaps();
 Thaw:
	unlock_device_hotplug();
	thaw_processes();
 Finish:
	pm_notifier_call_chain(PM_POST_RESTORE);
	pm_restore_console();
	atomic_inc(&snapshot_device_available);
	/* For success case, the suspend path will release the lock */
 Unlock:
	mutex_unlock(&pm_mutex);
	pr_debug("PM: Hibernation image not present or could not be loaded.\n");
	return error;
 Close_Finish:
	swsusp_close(FMODE_READ);
	goto Finish;
}
Esempio n. 3
0
static int software_resume(void)
{
	int error;
	unsigned int flags;

	/*
	 * If the user said "noresume".. bail out early.
	 */
	if (noresume)
		return 0;

	/*
	 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
	 * is configured into the kernel. Since the regular hibernate
	 * trigger path is via sysfs which takes a buffer mutex before
	 * calling hibernate functions (which take pm_mutex) this can
	 * cause lockdep to complain about a possible ABBA deadlock
	 * which cannot happen since we're in the boot code here and
	 * sysfs can't be invoked yet. Therefore, we use a subclass
	 * here to avoid lockdep complaining.
	 */
	mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);

	if (swsusp_resume_device)
		goto Check_image;

	if (!strlen(resume_file)) {
		error = -ENOENT;
		goto Unlock;
	}

	pr_debug("PM: Checking image partition %s\n", resume_file);

	/* Check if the device is there */
	swsusp_resume_device = name_to_dev_t(resume_file);
	if (!swsusp_resume_device) {
		/*
		 * Some device discovery might still be in progress; we need
		 * to wait for this to finish.
		 */
		wait_for_device_probe();
		/*
		 * We can't depend on SCSI devices being available after loading
		 * one of their modules until scsi_complete_async_scans() is
		 * called and the resume device usually is a SCSI one.
		 */
		scsi_complete_async_scans();

		swsusp_resume_device = name_to_dev_t(resume_file);
		if (!swsusp_resume_device) {
			error = -ENODEV;
			goto Unlock;
		}
	}

 Check_image:
	pr_debug("PM: Resume from partition %d:%d\n",
		MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));

	pr_debug("PM: Checking hibernation image.\n");
	error = swsusp_check();
	if (error)
		goto Unlock;

	/* The snapshot device should not be opened while we're running */
	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
		error = -EBUSY;
		swsusp_close(FMODE_READ);
		goto Unlock;
	}

	pm_prepare_console();
	error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
	if (error)
		goto close_finish;

	error = usermodehelper_disable();
	if (error)
		goto close_finish;

	error = create_basic_memory_bitmaps();
	if (error)
		goto close_finish;

	pr_debug("PM: Preparing processes for restore.\n");
	error = prepare_processes();
	if (error) {
		swsusp_close(FMODE_READ);
		goto Done;
	}

	pr_debug("PM: Reading hibernation image.\n");

	error = swsusp_read(&flags);
	swsusp_close(FMODE_READ);
	if (!error)
		hibernation_restore(flags & SF_PLATFORM_MODE);

	printk(KERN_ERR "PM: Restore failed, recovering.\n");
	swsusp_free();
	thaw_processes();
 Done:
	free_basic_memory_bitmaps();
	usermodehelper_enable();
 Finish:
	pm_notifier_call_chain(PM_POST_RESTORE);
	pm_restore_console();
	atomic_inc(&snapshot_device_available);
	/* For success case, the suspend path will release the lock */
 Unlock:
	mutex_unlock(&pm_mutex);
	pr_debug("PM: Resume from disk failed.\n");
	return error;
close_finish:
	swsusp_close(FMODE_READ);
	goto Finish;
}
Esempio n. 4
0
/**
 * hibernate - Carry out system hibernation, including saving the image.
 */
int hibernate(void)
{
	int error;

	if (!hibernation_available()) {
		pr_debug("PM: Hibernation not available.\n");
		return -EPERM;
	}

	lock_system_sleep();
	/* The snapshot device should not be opened while we're running */
	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
		error = -EBUSY;
		goto Unlock;
	}

	pm_prepare_console();
	error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
	if (error)
		goto Exit;

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

	error = freeze_processes();
	if (error)
		goto Exit;

	lock_device_hotplug();
	/* Allocate memory management structures */
	error = create_basic_memory_bitmaps();
	if (error)
		goto Thaw;

	error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
	if (error || freezer_test_done)
		goto Free_bitmaps;

	if (in_suspend) {
		unsigned int flags = 0;

		if (hibernation_mode == HIBERNATION_PLATFORM)
			flags |= SF_PLATFORM_MODE;
		if (nocompress)
			flags |= SF_NOCOMPRESS_MODE;
		else
		        flags |= SF_CRC32_MODE;

		pr_debug("PM: writing image.\n");
		error = swsusp_write(flags);
		swsusp_free();
		if (!error)
			power_down();
		in_suspend = 0;
		pm_restore_gfp_mask();
	} else {
		pr_debug("PM: Image restored successfully.\n");
	}

 Free_bitmaps:
	free_basic_memory_bitmaps();
 Thaw:
	unlock_device_hotplug();
	thaw_processes();

	/* Don't bother checking whether freezer_test_done is true */
	freezer_test_done = false;
 Exit:
	pm_notifier_call_chain(PM_POST_HIBERNATION);
	pm_restore_console();
	atomic_inc(&snapshot_device_available);
 Unlock:
	unlock_system_sleep();
	return error;
}
Esempio n. 5
0
int hibernate(void)
{
	int error;

	mutex_lock(&pm_mutex);
	/* The snapshot device should not be opened while we're running */
	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
		error = -EBUSY;
		goto Unlock;
	}

	pm_prepare_console();
	error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
	if (error)
		goto Exit;

	error = usermodehelper_disable();
	if (error)
		goto Exit;

	/* Allocate memory management structures */
	error = create_basic_memory_bitmaps();
	if (error)
		goto Exit;

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

	error = prepare_processes();
	if (error)
		goto Finish;

	if (hibernation_test(TEST_FREEZER))
		goto Thaw;

	if (hibernation_testmode(HIBERNATION_TESTPROC))
		goto Thaw;

	error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
	if (error)
		goto Thaw;

	if (in_suspend) {
		unsigned int flags = 0;

		if (hibernation_mode == HIBERNATION_PLATFORM)
			flags |= SF_PLATFORM_MODE;
		pr_debug("PM: writing image.\n");
		error = swsusp_write(flags);
		swsusp_free();
		if (!error)
			power_down();
	} else {
		pr_debug("PM: Image restored successfully.\n");
	}

 Thaw:
	thaw_processes();
 Finish:
	free_basic_memory_bitmaps();
	usermodehelper_enable();
 Exit:
	pm_notifier_call_chain(PM_POST_HIBERNATION);
	pm_restore_console();
	atomic_inc(&snapshot_device_available);
 Unlock:
	mutex_unlock(&pm_mutex);
	return error;
}