PM: Reduce code duplication between main.c and user.c

The SNAPSHOT_S2RAM ioctl code is outdated and it should not duplicate the
suspend code in kernel/power/main.c.  Fix that.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 7f19afe..bd0723a 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -255,47 +255,19 @@
 		break;
 
 	case SNAPSHOT_S2RAM:
-		if (!pm_ops) {
-			error = -ENOSYS;
-			break;
-		}
-
 		if (!data->frozen) {
 			error = -EPERM;
 			break;
 		}
-
 		if (!mutex_trylock(&pm_mutex)) {
 			error = -EBUSY;
 			break;
 		}
-
-		if (pm_ops->prepare) {
-			error = pm_ops->prepare(PM_SUSPEND_MEM);
-			if (error)
-				goto OutS3;
-		}
-
-		/* Put devices to sleep */
-		suspend_console();
-		error = device_suspend(PMSG_SUSPEND);
-		if (error) {
-			printk(KERN_ERR "Failed to suspend some devices.\n");
-		} else {
-			error = disable_nonboot_cpus();
-			if (!error) {
-				/* Enter S3, system is already frozen */
-				suspend_enter(PM_SUSPEND_MEM);
-				enable_nonboot_cpus();
-			}
-			/* Wake up devices */
-			device_resume();
-		}
-		resume_console();
-		if (pm_ops->finish)
-			pm_ops->finish(PM_SUSPEND_MEM);
-
- OutS3:
+		/*
+		 * Tasks are frozen and the notifiers have been called with
+		 * PM_HIBERNATION_PREPARE
+		 */
+		error = suspend_devices_and_enter(PM_SUSPEND_MEM);
 		mutex_unlock(&pm_mutex);
 		break;