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Diffstat (limited to 'arch/sh/include/asm/cmpxchg.h')
-rw-r--r--arch/sh/include/asm/cmpxchg.h70
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/sh/include/asm/cmpxchg.h b/arch/sh/include/asm/cmpxchg.h
new file mode 100644
index 000000000..f6bd1406b
--- /dev/null
+++ b/arch/sh/include/asm/cmpxchg.h
@@ -0,0 +1,70 @@
+#ifndef __ASM_SH_CMPXCHG_H
+#define __ASM_SH_CMPXCHG_H
+
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc..
+ */
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+
+#if defined(CONFIG_GUSA_RB)
+#include <asm/cmpxchg-grb.h>
+#elif defined(CONFIG_CPU_SH4A)
+#include <asm/cmpxchg-llsc.h>
+#else
+#include <asm/cmpxchg-irq.h>
+#endif
+
+extern void __xchg_called_with_bad_pointer(void);
+
+#define __xchg(ptr, x, size) \
+({ \
+ unsigned long __xchg__res; \
+ volatile void *__xchg_ptr = (ptr); \
+ switch (size) { \
+ case 4: \
+ __xchg__res = xchg_u32(__xchg_ptr, x); \
+ break; \
+ case 1: \
+ __xchg__res = xchg_u8(__xchg_ptr, x); \
+ break; \
+ default: \
+ __xchg_called_with_bad_pointer(); \
+ __xchg__res = x; \
+ break; \
+ } \
+ \
+ __xchg__res; \
+})
+
+#define xchg(ptr,x) \
+ ((__typeof__(*(ptr)))__xchg((ptr),(unsigned long)(x), sizeof(*(ptr))))
+
+/* This function doesn't exist, so you'll get a linker error
+ * if something tries to do an invalid cmpxchg(). */
+extern void __cmpxchg_called_with_bad_pointer(void);
+
+#define __HAVE_ARCH_CMPXCHG 1
+
+static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
+ unsigned long new, int size)
+{
+ switch (size) {
+ case 4:
+ return __cmpxchg_u32(ptr, old, new);
+ }
+ __cmpxchg_called_with_bad_pointer();
+ return old;
+}
+
+#define cmpxchg(ptr,o,n) \
+ ({ \
+ __typeof__(*(ptr)) _o_ = (o); \
+ __typeof__(*(ptr)) _n_ = (n); \
+ (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
+ (unsigned long)_n_, sizeof(*(ptr))); \
+ })
+
+#endif /* __ASM_SH_CMPXCHG_H */