1 files changed, 91 insertions, 0 deletions
diff --git a/arch/s390/include/asm/cmpxchg.h b/arch/s390/include/asm/cmpxchg.h
new file mode 100644
index 000000000..4eadec466
--- /dev/null
+++ b/arch/s390/include/asm/cmpxchg.h
@@ -0,0 +1,91 @@
+/*
+ * Copyright IBM Corp. 1999, 2011
+ *
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
+ */
+
+#ifndef __ASM_CMPXCHG_H
+#define __ASM_CMPXCHG_H
+
+#include <linux/mmdebug.h>
+#include <linux/types.h>
+#include <linux/bug.h>
+
+#define cmpxchg(ptr, o, n)						\
+({									\
+	__typeof__(*(ptr)) __o = (o);					\
+	__typeof__(*(ptr)) __n = (n);					\
+	(__typeof__(*(ptr))) __sync_val_compare_and_swap((ptr),__o,__n);\
+})
+
+#define cmpxchg64	cmpxchg
+#define cmpxchg_local	cmpxchg
+#define cmpxchg64_local	cmpxchg
+
+#define xchg(ptr, x)							\
+({									\
+	__typeof__(ptr) __ptr = (ptr);					\
+	__typeof__(*(ptr)) __old;					\
+	do {								\
+		__old = *__ptr;						\
+	} while (!__sync_bool_compare_and_swap(__ptr, __old, x));	\
+	__old;								\
+})
+
+#define __HAVE_ARCH_CMPXCHG
+
+#define __cmpxchg_double_op(p1, p2, o1, o2, n1, n2, insn)		\
+({									\
+	register __typeof__(*(p1)) __old1 asm("2") = (o1);		\
+	register __typeof__(*(p2)) __old2 asm("3") = (o2);		\
+	register __typeof__(*(p1)) __new1 asm("4") = (n1);		\
+	register __typeof__(*(p2)) __new2 asm("5") = (n2);		\
+	int cc;								\
+	asm volatile(							\
+			insn   " %[old],%[new],%[ptr]\n"		\
+		"	ipm	%[cc]\n"				\
+		"	srl	%[cc],28"				\
+		: [cc] "=d" (cc), [old] "+d" (__old1), "+d" (__old2)	\
+		: [new] "d" (__new1), "d" (__new2),			\
+		  [ptr] "Q" (*(p1)), "Q" (*(p2))			\
+		: "memory", "cc");					\
+	!cc;								\
+})
+
+#define __cmpxchg_double_4(p1, p2, o1, o2, n1, n2) \
+	__cmpxchg_double_op(p1, p2, o1, o2, n1, n2, "cds")
+
+#define __cmpxchg_double_8(p1, p2, o1, o2, n1, n2) \
+	__cmpxchg_double_op(p1, p2, o1, o2, n1, n2, "cdsg")
+
+extern void __cmpxchg_double_called_with_bad_pointer(void);
+
+#define __cmpxchg_double(p1, p2, o1, o2, n1, n2)			\
+({									\
+	int __ret;							\
+	switch (sizeof(*(p1))) {					\
+	case 4:								\
+		__ret = __cmpxchg_double_4(p1, p2, o1, o2, n1, n2);	\
+		break;							\
+	case 8:								\
+		__ret = __cmpxchg_double_8(p1, p2, o1, o2, n1, n2);	\
+		break;							\
+	default:							\
+		__cmpxchg_double_called_with_bad_pointer();		\
+	}								\
+	__ret;								\
+})
+
+#define cmpxchg_double(p1, p2, o1, o2, n1, n2)				\
+({									\
+	__typeof__(p1) __p1 = (p1);					\
+	__typeof__(p2) __p2 = (p2);					\
+	BUILD_BUG_ON(sizeof(*(p1)) != sizeof(long));			\
+	BUILD_BUG_ON(sizeof(*(p2)) != sizeof(long));			\
+	VM_BUG_ON((unsigned long)((__p1) + 1) != (unsigned long)(__p2));\
+	__cmpxchg_double_8(__p1, __p2, o1, o2, n1, n2);			\
+})
+
+#define system_has_cmpxchg_double()	1
+
+#endif /* __ASM_CMPXCHG_H */