Merge branch 'master'

1 files changed, 27 insertions, 0 deletions

diff --git a/include/asm-i386/futex.h b/include/asm-i386/futex.h
index 44b9db80647..7b8ceefd010 100644
--- a/include/asm-i386/futex.h
+++ b/include/asm-i386/futex.h
@@ -104,5 +104,32 @@ futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
 	return ret;
 }
 
+static inline int
+futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
+{
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+		return -EFAULT;
+
+	__asm__ __volatile__(
+		"1:	" LOCK_PREFIX "cmpxchgl %3, %1		\n"
+
+		"2:	.section .fixup, \"ax\"			\n"
+		"3:	mov     %2, %0				\n"
+		"	jmp     2b				\n"
+		"	.previous				\n"
+
+		"	.section __ex_table, \"a\"		\n"
+		"	.align  8				\n"
+		"	.long   1b,3b				\n"
+		"	.previous				\n"
+
+		: "=a" (oldval), "=m" (*uaddr)
+		: "i" (-EFAULT), "r" (newval), "0" (oldval)
+		: "memory"
+	);
+
+	return oldval;
+}
+
 #endif
 #endif