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-rw-r--r--arch/s390/include/asm/atomic.h285
1 files changed, 285 insertions, 0 deletions
diff --git a/arch/s390/include/asm/atomic.h b/arch/s390/include/asm/atomic.h
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+++ b/arch/s390/include/asm/atomic.h
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+#ifndef __ARCH_S390_ATOMIC__
+#define __ARCH_S390_ATOMIC__
+
+#include <linux/compiler.h>
+
+/*
+ * include/asm-s390/atomic.h
+ *
+ * S390 version
+ * Copyright (C) 1999-2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
+ * Denis Joseph Barrow,
+ * Arnd Bergmann (arndb@de.ibm.com)
+ *
+ * Derived from "include/asm-i386/bitops.h"
+ * Copyright (C) 1992, Linus Torvalds
+ *
+ */
+
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc..
+ * S390 uses 'Compare And Swap' for atomicity in SMP enviroment
+ */
+
+typedef struct {
+ int counter;
+} __attribute__ ((aligned (4))) atomic_t;
+#define ATOMIC_INIT(i) { (i) }
+
+#ifdef __KERNEL__
+
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
+
+#define __CS_LOOP(ptr, op_val, op_string) ({ \
+ typeof(ptr->counter) old_val, new_val; \
+ asm volatile( \
+ " l %0,%2\n" \
+ "0: lr %1,%0\n" \
+ op_string " %1,%3\n" \
+ " cs %0,%1,%2\n" \
+ " jl 0b" \
+ : "=&d" (old_val), "=&d" (new_val), \
+ "=Q" (((atomic_t *)(ptr))->counter) \
+ : "d" (op_val), "Q" (((atomic_t *)(ptr))->counter) \
+ : "cc", "memory"); \
+ new_val; \
+})
+
+#else /* __GNUC__ */
+
+#define __CS_LOOP(ptr, op_val, op_string) ({ \
+ typeof(ptr->counter) old_val, new_val; \
+ asm volatile( \
+ " l %0,0(%3)\n" \
+ "0: lr %1,%0\n" \
+ op_string " %1,%4\n" \
+ " cs %0,%1,0(%3)\n" \
+ " jl 0b" \
+ : "=&d" (old_val), "=&d" (new_val), \
+ "=m" (((atomic_t *)(ptr))->counter) \
+ : "a" (ptr), "d" (op_val), \
+ "m" (((atomic_t *)(ptr))->counter) \
+ : "cc", "memory"); \
+ new_val; \
+})
+
+#endif /* __GNUC__ */
+
+static inline int atomic_read(const atomic_t *v)
+{
+ barrier();
+ return v->counter;
+}
+
+static inline void atomic_set(atomic_t *v, int i)
+{
+ v->counter = i;
+ barrier();
+}
+
+static __inline__ int atomic_add_return(int i, atomic_t * v)
+{
+ return __CS_LOOP(v, i, "ar");
+}
+#define atomic_add(_i, _v) atomic_add_return(_i, _v)
+#define atomic_add_negative(_i, _v) (atomic_add_return(_i, _v) < 0)
+#define atomic_inc(_v) atomic_add_return(1, _v)
+#define atomic_inc_return(_v) atomic_add_return(1, _v)
+#define atomic_inc_and_test(_v) (atomic_add_return(1, _v) == 0)
+
+static __inline__ int atomic_sub_return(int i, atomic_t * v)
+{
+ return __CS_LOOP(v, i, "sr");
+}
+#define atomic_sub(_i, _v) atomic_sub_return(_i, _v)
+#define atomic_sub_and_test(_i, _v) (atomic_sub_return(_i, _v) == 0)
+#define atomic_dec(_v) atomic_sub_return(1, _v)
+#define atomic_dec_return(_v) atomic_sub_return(1, _v)
+#define atomic_dec_and_test(_v) (atomic_sub_return(1, _v) == 0)
+
+static __inline__ void atomic_clear_mask(unsigned long mask, atomic_t * v)
+{
+ __CS_LOOP(v, ~mask, "nr");
+}
+
+static __inline__ void atomic_set_mask(unsigned long mask, atomic_t * v)
+{
+ __CS_LOOP(v, mask, "or");
+}
+
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+static __inline__ int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
+ asm volatile(
+ " cs %0,%2,%1"
+ : "+d" (old), "=Q" (v->counter)
+ : "d" (new), "Q" (v->counter)
+ : "cc", "memory");
+#else /* __GNUC__ */
+ asm volatile(
+ " cs %0,%3,0(%2)"
+ : "+d" (old), "=m" (v->counter)
+ : "a" (v), "d" (new), "m" (v->counter)
+ : "cc", "memory");
+#endif /* __GNUC__ */
+ return old;
+}
+
+static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int c, old;
+ c = atomic_read(v);
+ for (;;) {
+ if (unlikely(c == u))
+ break;
+ old = atomic_cmpxchg(v, c, c + a);
+ if (likely(old == c))
+ break;
+ c = old;
+ }
+ return c != u;
+}
+
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+#undef __CS_LOOP
+
+#ifdef __s390x__
+typedef struct {
+ long long counter;
+} __attribute__ ((aligned (8))) atomic64_t;
+#define ATOMIC64_INIT(i) { (i) }
+
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
+
+#define __CSG_LOOP(ptr, op_val, op_string) ({ \
+ typeof(ptr->counter) old_val, new_val; \
+ asm volatile( \
+ " lg %0,%2\n" \
+ "0: lgr %1,%0\n" \
+ op_string " %1,%3\n" \
+ " csg %0,%1,%2\n" \
+ " jl 0b" \
+ : "=&d" (old_val), "=&d" (new_val), \
+ "=Q" (((atomic_t *)(ptr))->counter) \
+ : "d" (op_val), "Q" (((atomic_t *)(ptr))->counter) \
+ : "cc", "memory" ); \
+ new_val; \
+})
+
+#else /* __GNUC__ */
+
+#define __CSG_LOOP(ptr, op_val, op_string) ({ \
+ typeof(ptr->counter) old_val, new_val; \
+ asm volatile( \
+ " lg %0,0(%3)\n" \
+ "0: lgr %1,%0\n" \
+ op_string " %1,%4\n" \
+ " csg %0,%1,0(%3)\n" \
+ " jl 0b" \
+ : "=&d" (old_val), "=&d" (new_val), \
+ "=m" (((atomic_t *)(ptr))->counter) \
+ : "a" (ptr), "d" (op_val), \
+ "m" (((atomic_t *)(ptr))->counter) \
+ : "cc", "memory" ); \
+ new_val; \
+})
+
+#endif /* __GNUC__ */
+
+static inline long long atomic64_read(const atomic64_t *v)
+{
+ barrier();
+ return v->counter;
+}
+
+static inline void atomic64_set(atomic64_t *v, long long i)
+{
+ v->counter = i;
+ barrier();
+}
+
+static __inline__ long long atomic64_add_return(long long i, atomic64_t * v)
+{
+ return __CSG_LOOP(v, i, "agr");
+}
+#define atomic64_add(_i, _v) atomic64_add_return(_i, _v)
+#define atomic64_add_negative(_i, _v) (atomic64_add_return(_i, _v) < 0)
+#define atomic64_inc(_v) atomic64_add_return(1, _v)
+#define atomic64_inc_return(_v) atomic64_add_return(1, _v)
+#define atomic64_inc_and_test(_v) (atomic64_add_return(1, _v) == 0)
+
+static __inline__ long long atomic64_sub_return(long long i, atomic64_t * v)
+{
+ return __CSG_LOOP(v, i, "sgr");
+}
+#define atomic64_sub(_i, _v) atomic64_sub_return(_i, _v)
+#define atomic64_sub_and_test(_i, _v) (atomic64_sub_return(_i, _v) == 0)
+#define atomic64_dec(_v) atomic64_sub_return(1, _v)
+#define atomic64_dec_return(_v) atomic64_sub_return(1, _v)
+#define atomic64_dec_and_test(_v) (atomic64_sub_return(1, _v) == 0)
+
+static __inline__ void atomic64_clear_mask(unsigned long mask, atomic64_t * v)
+{
+ __CSG_LOOP(v, ~mask, "ngr");
+}
+
+static __inline__ void atomic64_set_mask(unsigned long mask, atomic64_t * v)
+{
+ __CSG_LOOP(v, mask, "ogr");
+}
+
+#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
+
+static __inline__ long long atomic64_cmpxchg(atomic64_t *v,
+ long long old, long long new)
+{
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
+ asm volatile(
+ " csg %0,%2,%1"
+ : "+d" (old), "=Q" (v->counter)
+ : "d" (new), "Q" (v->counter)
+ : "cc", "memory");
+#else /* __GNUC__ */
+ asm volatile(
+ " csg %0,%3,0(%2)"
+ : "+d" (old), "=m" (v->counter)
+ : "a" (v), "d" (new), "m" (v->counter)
+ : "cc", "memory");
+#endif /* __GNUC__ */
+ return old;
+}
+
+static __inline__ int atomic64_add_unless(atomic64_t *v,
+ long long a, long long u)
+{
+ long long c, old;
+ c = atomic64_read(v);
+ for (;;) {
+ if (unlikely(c == u))
+ break;
+ old = atomic64_cmpxchg(v, c, c + a);
+ if (likely(old == c))
+ break;
+ c = old;
+ }
+ return c != u;
+}
+
+#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
+
+#undef __CSG_LOOP
+#endif
+
+#define smp_mb__before_atomic_dec() smp_mb()
+#define smp_mb__after_atomic_dec() smp_mb()
+#define smp_mb__before_atomic_inc() smp_mb()
+#define smp_mb__after_atomic_inc() smp_mb()
+
+#include <asm-generic/atomic.h>
+#endif /* __KERNEL__ */
+#endif /* __ARCH_S390_ATOMIC__ */