x86: Add support for cmpxchg_double

[pandora-kernel.git] / arch / x86 / include / asm / cmpxchg_64.h

diff --git a/arch/x86/include/asm/cmpxchg_64.h b/arch/x86/include/asm/cmpxchg_64.h
index 423ae58..7cf5c0a 100644 (file)
--- a/arch/x86/include/asm/cmpxchg_64.h
+++ b/arch/x86/include/asm/cmpxchg_64.h
@@ -151,4 +151,49 @@ extern void __cmpxchg_wrong_size(void);
        cmpxchg_local((ptr), (o), (n));                                 \
 })
 
+#define cmpxchg16b(ptr, o1, o2, n1, n2)                                \
+({                                                             \
+       char __ret;                                             \
+       __typeof__(o2) __junk;                                  \
+       __typeof__(*(ptr)) __old1 = (o1);                       \
+       __typeof__(o2) __old2 = (o2);                           \
+       __typeof__(*(ptr)) __new1 = (n1);                       \
+       __typeof__(o2) __new2 = (n2);                           \
+       asm volatile(LOCK_PREFIX "cmpxchg16b %2;setz %1"        \
+                      : "=d"(__junk), "=a"(__ret), "+m" (*ptr) \
+                      : "b"(__new1), "c"(__new2),              \
+                        "a"(__old1), "d"(__old2));             \
+       __ret; })
+
+
+#define cmpxchg16b_local(ptr, o1, o2, n1, n2)                  \
+({                                                             \
+       char __ret;                                             \
+       __typeof__(o2) __junk;                                  \
+       __typeof__(*(ptr)) __old1 = (o1);                       \
+       __typeof__(o2) __old2 = (o2);                           \
+       __typeof__(*(ptr)) __new1 = (n1);                       \
+       __typeof__(o2) __new2 = (n2);                           \
+       asm volatile("cmpxchg16b %2;setz %1"                    \
+                      : "=d"(__junk), "=a"(__ret), "+m" (*ptr) \
+                      : "b"(__new1), "c"(__new2),              \
+                        "a"(__old1), "d"(__old2));             \
+       __ret; })
+
+#define cmpxchg_double(ptr, o1, o2, n1, n2)                            \
+({                                                                     \
+       BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
+       VM_BUG_ON((unsigned long)(ptr) % 16);                           \
+       cmpxchg16b((ptr), (o1), (o2), (n1), (n2));                      \
+})
+
+#define cmpxchg_double_local(ptr, o1, o2, n1, n2)                      \
+({                                                                     \
+       BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
+       VM_BUG_ON((unsigned long)(ptr) % 16);                           \
+       cmpxchg16b_local((ptr), (o1), (o2), (n1), (n2));                \
+})
+
+#define system_has_cmpxchg_double() cpu_has_cx16
+
 #endif /* _ASM_X86_CMPXCHG_64_H */