futex: Mark restart_block.futex.uaddr[2] __user

@uaddr and @uaddr2 fields in restart_block.futex are user
pointers. Add __user and remove unnecessary casts.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Darren Hart <dvhltc@us.ibm.com>
LKML-Reference: <1284468228-8723-2-git-send-email-namhyung@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index a8cc4e1..c9069654 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -23,12 +23,12 @@
 		};
 		/* For futex_wait and futex_wait_requeue_pi */
 		struct {
-			u32 *uaddr;
+			u32 __user *uaddr;
 			u32 val;
 			u32 flags;
 			u32 bitset;
 			u64 time;
-			u32 *uaddr2;
+			u32 __user *uaddr2;
 		} futex;
 		/* For nanosleep */
 		struct {