[PATCH] vt: add TIOCL_GETKMSGREDIRECT

Add TIOCL_GETKMSGREDIRECT needed by the userland suspend tool to get the
current value of kmsg_redirect from the kernel so that it can save it and
restore it after resume.

Signed-off-by: Rafael J. Wysocki <[e-mail]>
Acked-by: Pavel Machek <[e-mail]>
Cc: Michael Kerrisk <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/char/vt.c

···
 		case TIOCL_SETVESABLANK:
 			set_vesa_blanking(p);
 			break;
+		case TIOCL_GETKMSGREDIRECT:
+			data = kmsg_redirect;
+			ret = __put_user(data, p);
+			break;
 		case TIOCL_SETKMSGREDIRECT:
 			if (!capable(CAP_SYS_ADMIN)) {
 				ret = -EPERM;

include/linux/tiocl.h

···
 #define TIOCL_SCROLLCONSOLE	13	/* scroll console */
 #define TIOCL_BLANKSCREEN	14	/* keep screen blank even if a key is pressed */
 #define TIOCL_BLANKEDSCREEN	15	/* return which vt was blanked */
+#define TIOCL_GETKMSGREDIRECT	17	/* get the vt the kernel messages are restricted to */
 
 #endif /* _LINUX_TIOCL_H */