x86: Add support for cmpxchg_double

[pandora-kernel.git] / arch / x86 / include / asm / cmpxchg_32.h

diff --git a/arch/x86/include/asm/cmpxchg_32.h b/arch/x86/include/asm/cmpxchg_32.h
index 284a6e8..3deb725 100644 (file)
--- a/arch/x86/include/asm/cmpxchg_32.h
+++ b/arch/x86/include/asm/cmpxchg_32.h
@@ -280,4 +280,52 @@ static inline unsigned long cmpxchg_386(volatile void *ptr, unsigned long old,
 
 #endif
 
+#define cmpxchg8b(ptr, o1, o2, n1, n2)                         \
+({                                                             \
+       char __ret;                                             \
+       __typeof__(o2) __dummy;                                 \
+       __typeof__(*(ptr)) __old1 = (o1);                       \
+       __typeof__(o2) __old2 = (o2);                           \
+       __typeof__(*(ptr)) __new1 = (n1);                       \
+       __typeof__(o2) __new2 = (n2);                           \
+       asm volatile(LOCK_PREFIX "cmpxchg8b %2; setz %1"        \
+                      : "=d"(__dummy), "=a" (__ret), "+m" (*ptr)\
+                      : "a" (__old1), "d"(__old2),             \
+                        "b" (__new1), "c" (__new2)             \
+                      : "memory");                             \
+       __ret; })
+
+
+#define cmpxchg8b_local(ptr, o1, o2, n1, n2)                   \
+({                                                             \
+       char __ret;                                             \
+       __typeof__(o2) __dummy;                                 \
+       __typeof__(*(ptr)) __old1 = (o1);                       \
+       __typeof__(o2) __old2 = (o2);                           \
+       __typeof__(*(ptr)) __new1 = (n1);                       \
+       __typeof__(o2) __new2 = (n2);                           \
+       asm volatile("cmpxchg8b %2; setz %1"                    \
+                      : "=d"(__dummy), "=a"(__ret), "+m" (*ptr)\
+                      : "a" (__old), "d"(__old2),              \
+                        "b" (__new1), "c" (__new2),            \
+                      : "memory");                             \
+       __ret; })
+
+
+#define cmpxchg_double(ptr, o1, o2, n1, n2)                            \
+({                                                                     \
+       BUILD_BUG_ON(sizeof(*(ptr)) != 4);                              \
+       VM_BUG_ON((unsigned long)(ptr) % 8);                            \
+       cmpxchg8b((ptr), (o1), (o2), (n1), (n2));                       \
+})
+
+#define cmpxchg_double_local(ptr, o1, o2, n1, n2)                      \
+({                                                                     \
+       BUILD_BUG_ON(sizeof(*(ptr)) != 4);                              \
+       VM_BUG_ON((unsigned long)(ptr) % 8);                            \
+       cmpxchg16b_local((ptr), (o1), (o2), (n1), (n2));                        \
+})
+
+#define system_has_cmpxchg_double() cpu_has_cx8
+
 #endif /* _ASM_X86_CMPXCHG_32_H */