arm: atomic -- Use signed types for atomic_add_return/atomic_sub_return

Just like kernel does.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

arch/arm/include/asm/atomic.h

@@ -22,10 +22,10 @@ typedef struct {
 #define atomic_set(mem,v) ((mem)->counter = (v))
 #define atomic_get(v)	(*(volatile u32 *)&(v)->counter)
 
-static inline unsigned int atomic_add_return(int i, atomic_t *v)
+static inline int atomic_add_return(int i, atomic_t *v)
 {
 	unsigned long tmp;
-	unsigned int result;
+	int result;
 
 	smp_mb();
 
@@ -44,7 +44,7 @@ static inline unsigned int atomic_add_return(int i, atomic_t *v)
 	return result;
 }
 
-static inline unsigned int atomic_sub_return(int i, atomic_t *v)
+static inline int atomic_sub_return(int i, atomic_t *v)
 {
 	unsigned long tmp;
 	int result;
@@ -66,11 +66,11 @@ static inline unsigned int atomic_sub_return(int i, atomic_t *v)
 	return result;
 }
 
-static inline unsigned int atomic_inc(atomic_t *v) { return atomic_add_return(1, v) - 1; }
+static inline int atomic_inc(atomic_t *v) { return atomic_add_return(1, v) - 1; }
 
-static inline unsigned int atomic_add(atomic_t *v, unsigned int val) { return atomic_add_return(val, v) - val; }
+static inline int atomic_add(atomic_t *v, int val) { return atomic_add_return(val, v) - val; }
 
-static inline unsigned int atomic_dec(atomic_t *v) { return atomic_sub_return(1, v) + 1; }
+static inline int atomic_dec(atomic_t *v) { return atomic_sub_return(1, v) + 1; }
 
 /* true if the result is 0, or false for all other cases. */
 #define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)