alpha: fix build failures from system.h dismemberment

commit ec2212088c42ff7d1362629ec26dda4f3e8bdad3

    "Disintegrate asm/system.h for Alpha"

combined with commit b4816afa3986704d1404fc48e931da5135820472

    "Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h"

introduced the concept of asm/cmpxchg.h but the alpha arch
never got one.  Fork the cmpxchg content out of the asm/atomic.h
file to create one.

Some minor whitespace fixups were done on the block of code that
created the new file.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/cmpxchg.h b/arch/alpha/include/asm/cmpxchg.h
new file mode 100644
index 000000000000..429e8cd0d78e
--- /dev/null
+++ b/arch/alpha/include/asm/cmpxchg.h
@@ -0,0 +1,71 @@
+#ifndef _ALPHA_CMPXCHG_H
+#define _ALPHA_CMPXCHG_H
+
+/*
+ * Atomic exchange routines.
+ */
+
+#define __ASM__MB
+#define ____xchg(type, args...)		__xchg ## type ## _local(args)
+#define ____cmpxchg(type, args...)	__cmpxchg ## type ## _local(args)
+#include <asm/xchg.h>
+
+#define xchg_local(ptr, x)						\
+({									\
+	__typeof__(*(ptr)) _x_ = (x);					\
+	(__typeof__(*(ptr))) __xchg_local((ptr), (unsigned long)_x_,	\
+				       sizeof(*(ptr)));			\
+})
+
+#define cmpxchg_local(ptr, o, n)					\
+({									\
+	__typeof__(*(ptr)) _o_ = (o);					\
+	__typeof__(*(ptr)) _n_ = (n);					\
+	(__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_,	\
+					  (unsigned long)_n_,		\
+					  sizeof(*(ptr)));		\
+})
+
+#define cmpxchg64_local(ptr, o, n)					\
+({									\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 8);				\
+	cmpxchg_local((ptr), (o), (n));					\
+})
+
+#ifdef CONFIG_SMP
+#undef __ASM__MB
+#define __ASM__MB	"\tmb\n"
+#endif
+#undef ____xchg
+#undef ____cmpxchg
+#define ____xchg(type, args...)		__xchg ##type(args)
+#define ____cmpxchg(type, args...)	__cmpxchg ##type(args)
+#include <asm/xchg.h>
+
+#define xchg(ptr, x)							\
+({									\
+	__typeof__(*(ptr)) _x_ = (x);					\
+	(__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_,		\
+				 sizeof(*(ptr)));			\
+})
+
+#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)));\
+})
+
+#define cmpxchg64(ptr, o, n)						\
+({									\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 8);				\
+	cmpxchg((ptr), (o), (n));					\
+})
+
+#undef __ASM__MB
+#undef ____cmpxchg
+
+#define __HAVE_ARCH_CMPXCHG 1
+
+#endif /* _ALPHA_CMPXCHG_H */