remove software_suspend()

Remove software_suspend() and all its users since
pm_suspend(PM_SUSPEND_DISK) should be equivalent and there's no point in
having two interfaces for the same thing.

The patch also changes the valid_state function to return 0 (false) for
PM_SUSPEND_DISK when SOFTWARE_SUSPEND is not configured instead of
accepting it and having the whole thing fail later.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/power/main.c

@@ -184,17 +184,21 @@ static void suspend_finish(suspend_state_t state)
 static const char * const pm_states[PM_SUSPEND_MAX] = {
 	[PM_SUSPEND_STANDBY]	= "standby",
 	[PM_SUSPEND_MEM]	= "mem",
-#ifdef CONFIG_SOFTWARE_SUSPEND
 	[PM_SUSPEND_DISK]	= "disk",
-#endif
 };
 
 static inline int valid_state(suspend_state_t state)
 {
 	/* Suspend-to-disk does not really need low-level support.
-	 * It can work with reboot if needed. */
+	 * It can work with shutdown/reboot if needed. If it isn't
+	 * configured, then it cannot be supported.
+	 */
 	if (state == PM_SUSPEND_DISK)
+#ifdef CONFIG_SOFTWARE_SUSPEND
 		return 1;
+#else
+		return 0;
+#endif
 
 	/* all other states need lowlevel support and need to be
 	 * valid to the lowlevel implementation, no valid callback
@@ -244,17 +248,6 @@ static int enter_state(suspend_state_t state)
 	return error;
 }
 
-#ifdef CONFIG_SOFTWARE_SUSPEND
-/*
- * This is main interface to the outside world. It needs to be
- * called from process context.
- */
-int software_suspend(void)
-{
-	return enter_state(PM_SUSPEND_DISK);
-}
-#endif
-
 
 /**
  *	pm_suspend - Externally visible function for suspending system.

kernel/sys.c

@@ -881,7 +881,7 @@ asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user
 #ifdef CONFIG_SOFTWARE_SUSPEND
 	case LINUX_REBOOT_CMD_SW_SUSPEND:
 		{
-			int ret = software_suspend();
+			int ret = pm_suspend(PM_SUSPEND_DISK);
 			unlock_kernel();
 			return ret;
 		}