s390/atomic: refactor atomic primitives

Rework atomic.h to make the low level functions avaible for use
in other headers without using atomic_t, e.g. in bitops.h.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 130 insertions, 0 deletions

diff --git a/arch/s390/include/asm/atomic_ops.h b/arch/s390/include/asm/atomic_ops.h
new file mode 100644
index 000000000000..ac9e2b939d04
--- /dev/null
+++ b/arch/s390/include/asm/atomic_ops.h
@@ -0,0 +1,130 @@
+/*
+ * Low level function for atomic operations
+ *
+ * Copyright IBM Corp. 1999, 2016
+ */
+
+#ifndef __ARCH_S390_ATOMIC_OPS__
+#define __ARCH_S390_ATOMIC_OPS__
+
+#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
+
+#define __ATOMIC_OP(op_name, op_type, op_string, op_barrier)		\
+static inline op_type op_name(op_type val, op_type *ptr)		\
+{									\
+	op_type old;							\
+									\
+	asm volatile(							\
+		op_string "	%[old],%[val],%[ptr]\n"			\
+		op_barrier						\
+		: [old] "=d" (old), [ptr] "+Q" (*ptr)			\
+		: [val] "d" (val) : "cc", "memory");			\
+	return old;							\
+}									\
+
+#define __ATOMIC_OPS(op_name, op_type, op_string)			\
+	__ATOMIC_OP(op_name, op_type, op_string, "\n")			\
+	__ATOMIC_OP(op_name##_barrier, op_type, op_string, "bcr 14,0\n")
+
+__ATOMIC_OPS(__atomic_add, int, "laa")
+__ATOMIC_OPS(__atomic_and, int, "lan")
+__ATOMIC_OPS(__atomic_or,  int, "lao")
+__ATOMIC_OPS(__atomic_xor, int, "lax")
+
+__ATOMIC_OPS(__atomic64_add, long, "laag")
+__ATOMIC_OPS(__atomic64_and, long, "lang")
+__ATOMIC_OPS(__atomic64_or,  long, "laog")
+__ATOMIC_OPS(__atomic64_xor, long, "laxg")
+
+#undef __ATOMIC_OPS
+#undef __ATOMIC_OP
+
+static inline void __atomic_add_const(int val, int *ptr)
+{
+	asm volatile(
+		"	asi	%[ptr],%[val]\n"
+		: [ptr] "+Q" (*ptr) : [val] "i" (val) : "cc");
+}
+
+static inline void __atomic64_add_const(long val, long *ptr)
+{
+	asm volatile(
+		"	agsi	%[ptr],%[val]\n"
+		: [ptr] "+Q" (*ptr) : [val] "i" (val) : "cc");
+}
+
+#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
+
+#define __ATOMIC_OP(op_name, op_string)					\
+static inline int op_name(int val, int *ptr)				\
+{									\
+	int old, new;							\
+									\
+	asm volatile(							\
+		"0:	lr	%[new],%[old]\n"			\
+		op_string "	%[new],%[val]\n"			\
+		"	cs	%[old],%[new],%[ptr]\n"			\
+		"	jl	0b"					\
+		: [old] "=d" (old), [new] "=&d" (new), [ptr] "+Q" (*ptr)\
+		: [val] "d" (val), "0" (*ptr) : "cc", "memory");	\
+	return old;							\
+}
+
+#define __ATOMIC_OPS(op_name, op_string)				\
+	__ATOMIC_OP(op_name, op_string)					\
+	__ATOMIC_OP(op_name##_barrier, op_string)
+
+__ATOMIC_OPS(__atomic_add, "ar")
+__ATOMIC_OPS(__atomic_and, "nr")
+__ATOMIC_OPS(__atomic_or,  "or")
+__ATOMIC_OPS(__atomic_xor, "xr")
+
+#undef __ATOMIC_OPS
+
+#define __ATOMIC64_OP(op_name, op_string)				\
+static inline long op_name(long val, long *ptr)				\
+{									\
+	long old, new;							\
+									\
+	asm volatile(							\
+		"0:	lgr	%[new],%[old]\n"			\
+		op_string "	%[new],%[val]\n"			\
+		"	csg	%[old],%[new],%[ptr]\n"			\
+		"	jl	0b"					\
+		: [old] "=d" (old), [new] "=&d" (new), [ptr] "+Q" (*ptr)\
+		: [val] "d" (val), "0" (*ptr) : "cc", "memory");	\
+	return old;							\
+}
+
+#define __ATOMIC64_OPS(op_name, op_string)				\
+	__ATOMIC64_OP(op_name, op_string)				\
+	__ATOMIC64_OP(op_name##_barrier, op_string)
+
+__ATOMIC64_OPS(__atomic64_add, "agr")
+__ATOMIC64_OPS(__atomic64_and, "ngr")
+__ATOMIC64_OPS(__atomic64_or,  "ogr")
+__ATOMIC64_OPS(__atomic64_xor, "xgr")
+
+#undef __ATOMIC64_OPS
+
+#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
+
+static inline int __atomic_cmpxchg(int *ptr, int old, int new)
+{
+	asm volatile(
+		"	cs	%[old],%[new],%[ptr]"
+		: [old] "+d" (old), [ptr] "+Q" (*ptr)
+		: [new] "d" (new) : "cc", "memory");
+	return old;
+}
+
+static inline long __atomic64_cmpxchg(long *ptr, long old, long new)
+{
+	asm volatile(
+		"	csg	%[old],%[new],%[ptr]"
+		: [old] "+d" (old), [ptr] "+Q" (*ptr)
+		: [new] "d" (new) : "cc", "memory");
+	return old;
+}
+
+#endif /* __ARCH_S390_ATOMIC_OPS__  */