1 files changed, 137 insertions, 0 deletions
diff --git a/include/linux/byteorder/swabb.h b/include/linux/byteorder/swabb.h
new file mode 100644
index 00000000000..d28d9a804d3
--- /dev/null
+++ b/include/linux/byteorder/swabb.h
@@ -0,0 +1,137 @@
+#ifndef _LINUX_BYTEORDER_SWABB_H
+#define _LINUX_BYTEORDER_SWABB_H
+
+/*
+ * linux/byteorder/swabb.h
+ * SWAp Bytes Bizarrely
+ *	swaHHXX[ps]?(foo)
+ *
+ * Support for obNUXIous pdp-endian and other bizarre architectures.
+ * Will Linux ever run on such ancient beasts? if not, this file
+ * will be but a programming pearl. Still, it's a reminder that we
+ * shouldn't be making too many assumptions when trying to be portable.
+ *
+ */
+
+/*
+ * Meaning of the names I chose (vaxlinux people feel free to correct them):
+ * swahw32	swap 16-bit half-words in a 32-bit word
+ * swahb32	swap 8-bit halves of each 16-bit half-word in a 32-bit word
+ *
+ * No 64-bit support yet. I don't know NUXI conventions for long longs.
+ * I guarantee it will be a mess when it's there, though :->
+ * It will be even worse if there are conflicting 64-bit conventions.
+ * Hopefully, no one ever used 64-bit objects on NUXI machines.
+ *
+ */
+
+#define ___swahw32(x) \
+({ \
+	__u32 __x = (x); \
+	((__u32)( \
+		(((__u32)(__x) & (__u32)0x0000ffffUL) << 16) | \
+		(((__u32)(__x) & (__u32)0xffff0000UL) >> 16) )); \
+})
+#define ___swahb32(x) \
+({ \
+	__u32 __x = (x); \
+	((__u32)( \
+		(((__u32)(__x) & (__u32)0x00ff00ffUL) << 8) | \
+		(((__u32)(__x) & (__u32)0xff00ff00UL) >> 8) )); \
+})
+
+#define ___constant_swahw32(x) \
+	((__u32)( \
+		(((__u32)(x) & (__u32)0x0000ffffUL) << 16) | \
+		(((__u32)(x) & (__u32)0xffff0000UL) >> 16) ))
+#define ___constant_swahb32(x) \
+	((__u32)( \
+		(((__u32)(x) & (__u32)0x00ff00ffUL) << 8) | \
+		(((__u32)(x) & (__u32)0xff00ff00UL) >> 8) ))
+
+/*
+ * provide defaults when no architecture-specific optimization is detected
+ */
+#ifndef __arch__swahw32
+#  define __arch__swahw32(x) ___swahw32(x)
+#endif
+#ifndef __arch__swahb32
+#  define __arch__swahb32(x) ___swahb32(x)
+#endif
+
+#ifndef __arch__swahw32p
+#  define __arch__swahw32p(x) __swahw32(*(x))
+#endif
+#ifndef __arch__swahb32p
+#  define __arch__swahb32p(x) __swahb32(*(x))
+#endif
+
+#ifndef __arch__swahw32s
+#  define __arch__swahw32s(x) do { *(x) = __swahw32p((x)); } while (0)
+#endif
+#ifndef __arch__swahb32s
+#  define __arch__swahb32s(x) do { *(x) = __swahb32p((x)); } while (0)
+#endif
+
+
+/*
+ * Allow constant folding
+ */
+#if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)
+#  define __swahw32(x) \
+(__builtin_constant_p((__u32)(x)) ? \
+ ___swahw32((x)) : \
+ __fswahw32((x)))
+#  define __swahb32(x) \
+(__builtin_constant_p((__u32)(x)) ? \
+ ___swahb32((x)) : \
+ __fswahb32((x)))
+#else
+#  define __swahw32(x) __fswahw32(x)
+#  define __swahb32(x) __fswahb32(x)
+#endif /* OPTIMIZE */
+
+
+static __inline__ __const__ __u32 __fswahw32(__u32 x)
+{
+	return __arch__swahw32(x);
+}
+static __inline__ __u32 __swahw32p(__u32 *x)
+{
+	return __arch__swahw32p(x);
+}
+static __inline__ void __swahw32s(__u32 *addr)
+{
+	__arch__swahw32s(addr);
+}
+
+
+static __inline__ __const__ __u32 __fswahb32(__u32 x)
+{
+	return __arch__swahb32(x);
+}
+static __inline__ __u32 __swahb32p(__u32 *x)
+{
+	return __arch__swahb32p(x);
+}
+static __inline__ void __swahb32s(__u32 *addr)
+{
+	__arch__swahb32s(addr);
+}
+
+#ifdef __BYTEORDER_HAS_U64__
+/*
+ * Not supported yet
+ */
+#endif /* __BYTEORDER_HAS_U64__ */
+
+#if defined(__KERNEL__)
+#define swahw32 __swahw32
+#define swahb32 __swahb32
+#define swahw32p __swahw32p
+#define swahb32p __swahb32p
+#define swahw32s __swahw32s
+#define swahb32s __swahb32s
+#endif
+
+#endif /* _LINUX_BYTEORDER_SWABB_H */