atomic.h: add atomic64 cmpxchg, xchg and add_unless to parisc

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Acked-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-parisc/atomic.h

@@ -6,7 +6,6 @@
 #define _ASM_PARISC_ATOMIC_H_
 
 #include <linux/types.h>
-#include <asm/system.h>
 
 /*
  * Atomic operations that C can't guarantee us.  Useful for
@@ -163,7 +162,7 @@ static __inline__ int atomic_read(const atomic_t *v)
 }
 
 /* exported interface */
-#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
 
 /**
@@ -177,7 +176,7 @@ static __inline__ int atomic_read(const atomic_t *v)
  */
 #define atomic_add_unless(v, a, u)				\
 ({								\
-	int c, old;						\
+	__typeof__((v)->counter) c, old;						\
 	c = atomic_read(v);					\
 	while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
 		c = old;					\
@@ -270,6 +269,30 @@ atomic64_read(const atomic64_t *v)
 #define atomic64_dec_and_test(v)	(atomic64_dec_return(v) == 0)
 #define atomic64_sub_and_test(i,v)	(atomic64_sub_return((i),(v)) == 0)
 
+/* exported interface */
+#define atomic64_cmpxchg(v, o, n) \
+	((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
+#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
+
+/**
+ * atomic64_add_unless - add unless the number is a given value
+ * @v: pointer of type atomic64_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as it was not @u.
+ * Returns non-zero if @v was not @u, and zero otherwise.
+ */
+#define atomic64_add_unless(v, a, u)				\
+({								\
+	__typeof__((v)->counter) c, old;						\
+	c = atomic64_read(v);					\
+	while (c != (u) && (old = atomic64_cmpxchg((v), c, c + (a))) != c) \
+		c = old;					\
+	c != (u);						\
+})
+#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
+
 #endif /* CONFIG_64BIT */
 
 #include <asm-generic/atomic.h>