Commit 9b238205 authored by Luca Tettamanti's avatar Luca Tettamanti Committed by Linus Torvalds
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[PATCH] swsusp: add s2ram ioctl to userland interface 



Add the SNAPSHOT_S2RAM ioctl to the snapshot device.

This ioctl allows a userland application to make the system (previously frozen
with the SNAPSHOT_FREE ioctl) enter the S3 state without freezing processes
and disabling nonboot CPUs for the second time.

This will allow us to implement the suspend-to-disk-and-RAM (STDR)
functionality in the userland suspend tools.

Signed-off-by: default avatarLuca Tettamanti <kronos.it@gmail.com>
Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 94c188d3

kernel/power/main.c

+1 −1
Original line number Diff line number Diff line
@@ -103,7 +103,7 @@ static int suspend_prepare(suspend_state_t state) 
}





static int suspend_enter(suspend_state_t state)

int suspend_enter(suspend_state_t state)

{

	int error = 0;

	unsigned long flags;

kernel/power/power.h

+3 −1
Original line number Diff line number Diff line
@@ -77,7 +77,8 @@ int snapshot_image_loaded(struct snapshot_handle *handle); 
#define SNAPSHOT_GET_SWAP_PAGE		_IOR(SNAPSHOT_IOC_MAGIC, 8, void *)

#define SNAPSHOT_FREE_SWAP_PAGES	_IO(SNAPSHOT_IOC_MAGIC, 9)

#define SNAPSHOT_SET_SWAP_FILE		_IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)

#define SNAPSHOT_IOC_MAXNR	10

#define SNAPSHOT_S2RAM			_IO(SNAPSHOT_IOC_MAGIC, 11)

#define SNAPSHOT_IOC_MAXNR	11



/**

 *	The bitmap is used for tracing allocated swap pages
@@ -112,3 +113,4 @@ extern int swsusp_resume(void); 
extern int swsusp_read(void);

extern int swsusp_write(void);

extern void swsusp_close(void);

extern int suspend_enter(suspend_state_t state);

kernel/power/user.c

+36 −0
Original line number Diff line number Diff line
@@ -266,6 +266,42 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, 
		}

		break;



	case SNAPSHOT_S2RAM:

		if (!data->frozen) {

			error = -EPERM;

			break;

		}



		if (down_trylock(&pm_sem)) {

			error = -EBUSY;

			break;

		}



		if (pm_ops->prepare) {

			error = pm_ops->prepare(PM_SUSPEND_MEM);

			if (error)

				goto OutS3;

		}



		/* Put devices to sleep */

		error = device_suspend(PMSG_SUSPEND);

		if (error) {

			printk(KERN_ERR "Failed to suspend some devices.\n");

		} else {

			/* Enter S3, system is already frozen */

			suspend_enter(PM_SUSPEND_MEM);



			/* Wake up devices */

			device_resume();

		}



		if (pm_ops->finish)

			pm_ops->finish(PM_SUSPEND_MEM);



OutS3:

		up(&pm_sem);

		break;



	default:

		error = -ENOTTY;