X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=include%2Fasm-powerpc%2Fatomic.h;h=c44810b9d3224dbc54474b4a6cb7eab5a2a9af3d;hb=dda034bcb51a0a28318046d74d664e0fc5f7d1d4;hp=53283e2540b381ff086508d69052dd1b188bc6d1;hpb=e2a3d40258fe20d205f8ed592e1e2c0d5529c2e1;p=linux-2.6-omap-h63xx.git

diff --git a/include/asm-powerpc/atomic.h b/include/asm-powerpc/atomic.h
index 53283e2540b..c44810b9d32 100644
--- a/include/asm-powerpc/atomic.h
+++ b/include/asm-powerpc/atomic.h
@@ -11,6 +11,7 @@ typedef struct { volatile int counter; } atomic_t;
 #include <linux/compiler.h>
 #include <asm/synch.h>
 #include <asm/asm-compat.h>
+#include <asm/system.h>
 
 #define ATOMIC_INIT(i)		{ (i) }
 
@@ -165,7 +166,7 @@ static __inline__ int atomic_dec_return(atomic_t *v)
 	return t;
 }
 
-#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))
 
 /**
@@ -207,7 +208,8 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
 
 /*
  * Atomically test *v and decrement if it is greater than 0.
- * The function returns the old value of *v minus 1.
+ * The function returns the old value of *v minus 1, even if
+ * the atomic variable, v, was not decremented.
  */
 static __inline__ int atomic_dec_if_positive(atomic_t *v)
 {
@@ -216,14 +218,15 @@ static __inline__ int atomic_dec_if_positive(atomic_t *v)
 	__asm__ __volatile__(
 	LWSYNC_ON_SMP
 "1:	lwarx	%0,0,%1		# atomic_dec_if_positive\n\
-	addic.	%0,%0,-1\n\
+	cmpwi	%0,1\n\
+	addi	%0,%0,-1\n\
 	blt-	2f\n"
 	PPC405_ERR77(0,%1)
 "	stwcx.	%0,0,%1\n\
 	bne-	1b"
 	ISYNC_ON_SMP
 	"\n\
-2:"	: "=&r" (t)
+2:"	: "=&b" (t)
 	: "r" (&v->counter)
 	: "cc", "memory");
 
@@ -411,6 +414,42 @@ static __inline__ long atomic64_dec_if_positive(atomic64_t *v)
 	return t;
 }
 
+#define atomic64_cmpxchg(v, o, n) (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.
+ */
+static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
+{
+	long t;
+
+	__asm__ __volatile__ (
+	LWSYNC_ON_SMP
+"1:	ldarx	%0,0,%1		# atomic_add_unless\n\
+	cmpd	0,%0,%3 \n\
+	beq-	2f \n\
+	add	%0,%2,%0 \n"
+"	stdcx.	%0,0,%1 \n\
+	bne-	1b \n"
+	ISYNC_ON_SMP
+"	subf	%0,%2,%0 \n\
+2:"
+	: "=&r" (t)
+	: "r" (&v->counter), "r" (a), "r" (u)
+	: "cc", "memory");
+
+	return t != u;
+}
+
+#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
+
 #endif /* __powerpc64__ */
 
 #include <asm-generic/atomic.h>