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-rw-r--r--arch/cris/include/asm/atomic.h164
1 files changed, 164 insertions, 0 deletions
diff --git a/arch/cris/include/asm/atomic.h b/arch/cris/include/asm/atomic.h
new file mode 100644
index 00000000000..f71ea686a2e
--- /dev/null
+++ b/arch/cris/include/asm/atomic.h
@@ -0,0 +1,164 @@
+/* $Id: atomic.h,v 1.3 2001/07/25 16:15:19 bjornw Exp $ */
+
+#ifndef __ASM_CRIS_ATOMIC__
+#define __ASM_CRIS_ATOMIC__
+
+#include <linux/compiler.h>
+
+#include <asm/system.h>
+#include <arch/atomic.h>
+
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc..
+ */
+
+typedef struct { volatile int counter; } atomic_t;
+
+#define ATOMIC_INIT(i) { (i) }
+
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+/* These should be written in asm but we do it in C for now. */
+
+static inline void atomic_add(int i, volatile atomic_t *v)
+{
+ unsigned long flags;
+ cris_atomic_save(v, flags);
+ v->counter += i;
+ cris_atomic_restore(v, flags);
+}
+
+static inline void atomic_sub(int i, volatile atomic_t *v)
+{
+ unsigned long flags;
+ cris_atomic_save(v, flags);
+ v->counter -= i;
+ cris_atomic_restore(v, flags);
+}
+
+static inline int atomic_add_return(int i, volatile atomic_t *v)
+{
+ unsigned long flags;
+ int retval;
+ cris_atomic_save(v, flags);
+ retval = (v->counter += i);
+ cris_atomic_restore(v, flags);
+ return retval;
+}
+
+#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
+
+static inline int atomic_sub_return(int i, volatile atomic_t *v)
+{
+ unsigned long flags;
+ int retval;
+ cris_atomic_save(v, flags);
+ retval = (v->counter -= i);
+ cris_atomic_restore(v, flags);
+ return retval;
+}
+
+static inline int atomic_sub_and_test(int i, volatile atomic_t *v)
+{
+ int retval;
+ unsigned long flags;
+ cris_atomic_save(v, flags);
+ retval = (v->counter -= i) == 0;
+ cris_atomic_restore(v, flags);
+ return retval;
+}
+
+static inline void atomic_inc(volatile atomic_t *v)
+{
+ unsigned long flags;
+ cris_atomic_save(v, flags);
+ (v->counter)++;
+ cris_atomic_restore(v, flags);
+}
+
+static inline void atomic_dec(volatile atomic_t *v)
+{
+ unsigned long flags;
+ cris_atomic_save(v, flags);
+ (v->counter)--;
+ cris_atomic_restore(v, flags);
+}
+
+static inline int atomic_inc_return(volatile atomic_t *v)
+{
+ unsigned long flags;
+ int retval;
+ cris_atomic_save(v, flags);
+ retval = ++(v->counter);
+ cris_atomic_restore(v, flags);
+ return retval;
+}
+
+static inline int atomic_dec_return(volatile atomic_t *v)
+{
+ unsigned long flags;
+ int retval;
+ cris_atomic_save(v, flags);
+ retval = --(v->counter);
+ cris_atomic_restore(v, flags);
+ return retval;
+}
+static inline int atomic_dec_and_test(volatile atomic_t *v)
+{
+ int retval;
+ unsigned long flags;
+ cris_atomic_save(v, flags);
+ retval = --(v->counter) == 0;
+ cris_atomic_restore(v, flags);
+ return retval;
+}
+
+static inline int atomic_inc_and_test(volatile atomic_t *v)
+{
+ int retval;
+ unsigned long flags;
+ cris_atomic_save(v, flags);
+ retval = ++(v->counter) == 0;
+ cris_atomic_restore(v, flags);
+ return retval;
+}
+
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ int ret;
+ unsigned long flags;
+
+ cris_atomic_save(v, flags);
+ ret = v->counter;
+ if (likely(ret == old))
+ v->counter = new;
+ cris_atomic_restore(v, flags);
+ return ret;
+}
+
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+static inline int atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int ret;
+ unsigned long flags;
+
+ cris_atomic_save(v, flags);
+ ret = v->counter;
+ if (ret != u)
+ v->counter += a;
+ cris_atomic_restore(v, flags);
+ return ret != u;
+}
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+/* Atomic operations are already serializing */
+#define smp_mb__before_atomic_dec() barrier()
+#define smp_mb__after_atomic_dec() barrier()
+#define smp_mb__before_atomic_inc() barrier()
+#define smp_mb__after_atomic_inc() barrier()
+
+#include <asm-generic/atomic.h>
+#endif