[PATCH 2/5] byteorder: add include/linux/byteorder.h to define endian helpers

Harvey Harrison
2008-07-04T04:13:30Z

In the new implementaion, __constant_le16_to_cpu, etc are no longer needed
as the base __le16_to_cpu will now get folded at compile time. The __constant
versions can be removed over time...see the code comment.

__LITTLE_ENDIAN, __BIG_ENDIAN guards are now consolidated in the common byteorder.h
which means tests for one or the other can be removed from elsewhere in the tree.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
---
include/linux/byteorder.h | 312 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 312 insertions(+), 0 deletions(-)

diff --git a/include/linux/byteorder.h b/include/linux/byteorder.h
new file mode 100644
index 0000000..5087aaf
--- /dev/null
+++ b/include/linux/byteorder.h
@@ -0,0 +1,312 @@
+#ifndef _LINUX_BYTEORDER_H
+#define _LINUX_BYTEORDER_H
+
+#include <linux/types.h>
+#include <linux/swab.h>
+
+#if defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
+# error Fix asm/byteorder.h to define one endianness
+#endif
+
+#if !defined(__LITTLE_ENDIAN) && !defined(__BIG_ENDIAN)
+# error Fix asm/byteorder.h to define arch endianness
+#endif
+
+#ifdef __LITTLE_ENDIAN
+# undef __LITTLE_ENDIAN
+# define __LITTLE_ENDIAN 1234
+#endif
+
+#ifdef __BIG_ENDIAN
+# undef __BIG_ENDIAN
+# define __BIG_ENDIAN 4321
+#endif
+
+#if defined(__LITTLE_ENDIAN) && !defined(__LITTLE_ENDIAN_BITFIELD)
+# define __LITTLE_ENDIAN_BITFIELD
+#endif
+
+#if defined(__BIG_ENDIAN) && !defined(__BIG_ENDIAN_BITFIELD)
+# define __BIG_ENDIAN_BITFIELD
+#endif
+
+#ifdef __LITTLE_ENDIAN
+# define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
+# define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
+# define __le64_to_cpu(x) ((__force __u64)(__le64)(x))
+# define __cpu_to_le16(x) ((__force __le16)(__u16)(x))
+# define __cpu_to_le32(x) ((__force __le32)(__u32)(x))
+# define __cpu_to_le64(x) ((__force __le64)(__u64)(x))
+# define __le16_to_cpus(x) do {} while (0)
+# define __le32_to_cpus(x) do {} while (0)
+# define __le64_to_cpus(x) do {} while (0)
+# define __cpu_to_le16s(x) do {} while (0)
+# define __cpu_to_le32s(x) do {} while (0)
+# define __cpu_to_le64s(x) do {} while (0)
+
+# define __be16_to_cpu(x) __swab16((__force __u16)(__be16)(x))
+# define __be32_to_cpu(x) __swab32((__force __u32)(__be32)(x))
+# define __be64_to_cpu(x) __swab64((__force __u64)(__be64)(x))
+# define __cpu_to_be16(x) ((__force __be16)__swab16(x))
+# define __cpu_to_be32(x) ((__force __be32)__swab32(x))
+# define __cpu_to_be64(x) ((__force __be64)__swab64(x))
+# define __be16_to_cpus(x) __swab16s(x)
+# define __be32_to_cpus(x) __swab32s(x)
+# define __be64_to_cpus(x) __swab64s(x)
+# define __cpu_to_be16s(x) __swab16s(x)
+# define __cpu_to_be32s(x) __swab32s(x)
+# define __cpu_to_be64s(x) __swab64s(x)
+#endif
+
+#ifdef __BIG_ENDIAN
+# define __be16_to_cpu(x) ((__force __u16)(__be16)(x))
+# define __be32_to_cpu(x) ((__force __u32)(__be32)(x))
+# define __be64_to_cpu(x) ((__force __u64)(__be64)(x))
+# define __cpu_to_be16(x) ((__force __be16)(__u16)(x))
+# define __cpu_to_be32(x) ((__force __be32)(__u32)(x))
+# define __cpu_to_be64(x) ((__force __be64)(__u64)(x))
+# define __be16_to_cpus(x) do {} while (0)
+# define __be32_to_cpus(x) do {} while (0)
+# define __be64_to_cpus(x) do {} while (0)
+# define __cpu_to_be16s(x) do {} while (0)
+# define __cpu_to_be32s(x) do {} while (0)
+# define __cpu_to_be64s(x) do {} while (0)
+
+# define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
+# define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
+# define __le64_to_cpu(x) __swab64((__force __u64)(__le64)(x))
+# define __cpu_to_le16(x) ((__force __le16)__swab16(x))
+# define __cpu_to_le32(x) ((__force __le32)__swab32(x))
+# define __cpu_to_le64(x) ((__force __le64)__swab64(x))
+# define __le16_to_cpus(x) __swab16s(x)
+# define __le32_to_cpus(x) __swab32s(x)
+# define __le64_to_cpus(x) __swab64s(x)
+# define __cpu_to_le16s(x) __swab16s(x)
+# define __cpu_to_le32s(x) __swab32s(x)
+# define __cpu_to_le64s(x) __swab64s(x)
+#endif
+
+/*
+ * These helpers could be phased out over time as the base version
+ * handles constant folding.
+ */
+#define __constant_htonl(x) __cpu_to_be32(x)
+#define __constant_ntohl(x) __be32_to_cpu(x)
+#define __constant_htons(x) __cpu_to_be16(x)
+#define __constant_ntohs(x) __be16_to_cpu(x)
+
+#define __constant_le16_to_cpu(x) __le16_to_cpu(x)
+#define __constant_le32_to_cpu(x) __le32_to_cpu(x)
+#define __constant_le64_to_cpu(x) __le64_to_cpu(x)
+#define __constant_be16_to_cpu(x) __be16_to_cpu(x)
+#define __constant_be32_to_cpu(x) __be32_to_cpu(x)
+#define __constant_be64_to_cpu(x) __be64_to_cpu(x)
+
+#define __constant_cpu_to_le16(x) __cpu_to_le16(x)
+#define __constant_cpu_to_le32(x) __cpu_to_le32(x)
+#define __constant_cpu_to_le64(x) __cpu_to_le64(x)
+#define __constant_cpu_to_be16(x) __cpu_to_be16(x)
+#define __constant_cpu_to_be32(x) __cpu_to_be32(x)
+#define __constant_cpu_to_be64(x) __cpu_to_be64(x)
+
+static inline __u16 __le16_to_cpup(const __le16 *p)
+{
+#ifdef __LITTLE_ENDIAN
+ return (__force __u16)*p;
+#else
+ return __swab16p((__force __u16 *)p);
+#endif
+}
+
+static inline __u32 __le32_to_cpup(const __le32 *p)
+{
+#ifdef __LITTLE_ENDIAN
+ return (__force __u32)*p;
+#else
+ return __swab32p((__force __u32 *)p);
+#endif
+}
+
+static inline __u64 __le64_to_cpup(const __le64 *p)
+{
+#ifdef __LITTLE_ENDIAN
+ return (__force __u64)*p;
+#else
+ return __swab64p((__force __u64 *)p);
+#endif
+}
+
+static inline __le16 __cpu_to_le16p(const __u16 *p)
+{
+#ifdef __LITTLE_ENDIAN
+ return (__force __le16)*p;
+#else
+ return (__force __le16)__swab16p(p);
+#endif
+}
+
+static inline __le32 __cpu_to_le32p(const __u32 *p)
+{
+#ifdef __LITTLE_ENDIAN
+ return (__force __le32)*p;
+#else
+ return (__force __le32)__swab32p(p);
+#endif
+}
+
+static inline __le64 __cpu_to_le64p(const __u64 *p)
+{
+#ifdef __LITTLE_ENDIAN
+ return (__force __le64)*p;
+#else
+ return (__force __le64)__swab64p(p);
+#endif
+}
+
+static inline __u16 __be16_to_cpup(const __be16 *p)
+{
+#ifdef __BIG_ENDIAN
+ return (__force __u16)*p;
+#else
+ return __swab16p((__force __u16 *)p);
+#endif
+}
+
+static inline __u32 __be32_to_cpup(const __be32 *p)
+{
+#ifdef __BIG_ENDIAN
+ return (__force __u32)*p;
+#else
+ return __swab32p((__force __u32 *)p);
+#endif
+}
+
+static inline __u64 __be64_to_cpup(const __be64 *p)
+{
+#ifdef __BIG_ENDIAN
+ return (__force __u64)*p;
+#else
+ return __swab64p((__force __u64 *)p);
+#endif
+}
+
+static inline __be16 __cpu_to_be16p(const __u16 *p)
+{
+#ifdef __BIG_ENDIAN
+ return (__force __be16)*p;
+#else
+ return (__force __be16)__swab16p(p);
+#endif
+}
+
+static inline __be32 __cpu_to_be32p(const __u32 *p)
+{
+#ifdef __BIG_ENDIAN
+ return (__force __be32)*p;
+#else
+ return (__force __be32)__swab32p(p);
+#endif
+}
+
+static inline __be64 __cpu_to_be64p(const __u64 *p)
+{
+#ifdef __BIG_ENDIAN
+ return (__force __be64)*p;
+#else
+ return (__force __be64)__swab64p(p);
+#endif
+}
+
+#ifdef __KERNEL__
+
+# define le16_to_cpu __le16_to_cpu
+# define le32_to_cpu __le32_to_cpu
+# define le64_to_cpu __le64_to_cpu
+# define be16_to_cpu __be16_to_cpu
+# define be32_to_cpu __be32_to_cpu
+# define be64_to_cpu __be64_to_cpu
+# define cpu_to_le16 __cpu_to_le16
+# define cpu_to_le32 __cpu_to_le32
+# define cpu_to_le64 __cpu_to_le64
+# define cpu_to_be16 __cpu_to_be16
+# define cpu_to_be32 __cpu_to_be32
+# define cpu_to_be64 __cpu_to_be64
+
+# define le16_to_cpup __le16_to_cpup
+# define le32_to_cpup __le32_to_cpup
+# define le64_to_cpup __le64_to_cpup
+# define be16_to_cpup __be16_to_cpup
+# define be32_to_cpup __be32_to_cpup
+# define be64_to_cpup __be64_to_cpup
+# define cpu_to_le16p __cpu_to_le16p
+# define cpu_to_le32p __cpu_to_le32p
+# define cpu_to_le64p __cpu_to_le64p
+# define cpu_to_be16p __cpu_to_be16p
+# define cpu_to_be32p __cpu_to_be32p
+# define cpu_to_be64p __cpu_to_be64p
+
+# define le16_to_cpus __le16_to_cpus
+# define le32_to_cpus __le32_to_cpus
+# define le64_to_cpus __le64_to_cpus
+# define be16_to_cpus __be16_to_cpus
+# define be32_to_cpus __be32_to_cpus
+# define be64_to_cpus __be64_to_cpus
+# define cpu_to_le16s __cpu_to_le16s
+# define cpu_to_le32s __cpu_to_le32s
+# define cpu_to_le64s __cpu_to_le64s
+# define cpu_to_be16s __cpu_to_be16s
+# define cpu_to_be32s __cpu_to_be32s
+# define cpu_to_be64s __cpu_to_be64s
+
+/*
+ * They have to be macros in order to do the constant folding
+ * correctly - if the argument passed into a inline function
+ * it is no longer constant according to gcc..
+ */
+# undef ntohl
+# undef ntohs
+# undef htonl
+# undef htons
+
+# define ___htonl(x) __cpu_to_be32(x)
+# define ___htons(x) __cpu_to_be16(x)
+# define ___ntohl(x) __be32_to_cpu(x)
+# define ___ntohs(x) __be16_to_cpu(x)
+
+# define htonl(x) ___htonl(x)
+# define ntohl(x) ___ntohl(x)
+# define htons(x) ___htons(x)
+# define ntohs(x) ___ntohs(x)
+
+static inline void le16_add_cpu(__le16 *var, u16 val)
+{
+ *var = cpu_to_le16(le16_to_cpup(var) + val);
+}
+
+static inline void le32_add_cpu(__le32 *var, u32 val)
+{
+ *var = cpu_to_le32(le32_to_cpup(var) + val);
+}
+
+static inline void le64_add_cpu(__le64 *var, u64 val)
+{
+ *var = cpu_to_le64(le64_to_cpup(var) + val);
+}
+
+static inline void be16_add_cpu(__be16 *var, u16 val)
+{
+ *var = cpu_to_be16(be16_to_cpup(var) + val);
+}
+
+static inline void be32_add_cpu(__be32 *var, u32 val)
+{
+ *var = cpu_to_be32(be32_to_cpup(var) + val);
+}
+
+static inline void be64_add_cpu(__be64 *var, u64 val)
+{
+ *var = cpu_to_be64(be64_to_cpup(var) + val);
+}
+
+#endif /* __KERNEL__ */
+#endif /* _LINUX_BYTEORDER_H */
--
1.5.6.1.281.g1087e