1 files changed, 172 insertions, 0 deletions

diff --git a/include/linux/byteorder/generic.h b/include/linux/byteorder/generic.h
new file mode 100644
index 000000000000..5fde6f4d6c1e
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+++ b/include/linux/byteorder/generic.h
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+#ifndef _LINUX_BYTEORDER_GENERIC_H
+#define _LINUX_BYTEORDER_GENERIC_H
+
+/*
+ * linux/byteorder_generic.h
+ * Generic Byte-reordering support
+ *
+ * Francois-Rene Rideau <fare@tunes.org> 19970707
+ *    gathered all the good ideas from all asm-foo/byteorder.h into one file,
+ *    cleaned them up.
+ *    I hope it is compliant with non-GCC compilers.
+ *    I decided to put __BYTEORDER_HAS_U64__ in byteorder.h,
+ *    because I wasn't sure it would be ok to put it in types.h
+ *    Upgraded it to 2.1.43
+ * Francois-Rene Rideau <fare@tunes.org> 19971012
+ *    Upgraded it to 2.1.57
+ *    to please Linus T., replaced huge #ifdef's between little/big endian
+ *    by nestedly #include'd files.
+ * Francois-Rene Rideau <fare@tunes.org> 19971205
+ *    Made it to 2.1.71; now a facelift:
+ *    Put files under include/linux/byteorder/
+ *    Split swab from generic support.
+ *
+ * TODO:
+ *   = Regular kernel maintainers could also replace all these manual
+ *    byteswap macros that remain, disseminated among drivers,
+ *    after some grep or the sources...
+ *   = Linus might want to rename all these macros and files to fit his taste,
+ *    to fit his personal naming scheme.
+ *   = it seems that a few drivers would also appreciate
+ *    nybble swapping support...
+ *   = every architecture could add their byteswap macro in asm/byteorder.h
+ *    see how some architectures already do (i386, alpha, ppc, etc)
+ *   = cpu_to_beXX and beXX_to_cpu might some day need to be well
+ *    distinguished throughout the kernel. This is not the case currently,
+ *    since little endian, big endian, and pdp endian machines needn't it.
+ *    But this might be the case for, say, a port of Linux to 20/21 bit
+ *    architectures (and F21 Linux addict around?).
+ */
+
+/*
+ * The following macros are to be defined by <asm/byteorder.h>:
+ *
+ * Conversion of long and short int between network and host format
+ *      ntohl(__u32 x)
+ *      ntohs(__u16 x)
+ *      htonl(__u32 x)
+ *      htons(__u16 x)
+ * It seems that some programs (which? where? or perhaps a standard? POSIX?)
+ * might like the above to be functions, not macros (why?).
+ * if that's true, then detect them, and take measures.
+ * Anyway, the measure is: define only ___ntohl as a macro instead,
+ * and in a separate file, have
+ * unsigned long inline ntohl(x){return ___ntohl(x);}
+ *
+ * The same for constant arguments
+ *      __constant_ntohl(__u32 x)
+ *      __constant_ntohs(__u16 x)
+ *      __constant_htonl(__u32 x)
+ *      __constant_htons(__u16 x)
+ *
+ * Conversion of XX-bit integers (16- 32- or 64-)
+ * between native CPU format and little/big endian format
+ * 64-bit stuff only defined for proper architectures
+ *      cpu_to_[bl]eXX(__uXX x)
+ *      [bl]eXX_to_cpu(__uXX x)
+ *
+ * The same, but takes a pointer to the value to convert
+ *      cpu_to_[bl]eXXp(__uXX x)
+ *      [bl]eXX_to_cpup(__uXX x)
+ *
+ * The same, but change in situ
+ *      cpu_to_[bl]eXXs(__uXX x)
+ *      [bl]eXX_to_cpus(__uXX x)
+ *
+ * See asm-foo/byteorder.h for examples of how to provide
+ * architecture-optimized versions
+ *
+ */
+
+
+#if defined(__KERNEL__)
+/*
+ * inside the kernel, we can use nicknames;
+ * outside of it, we must avoid POSIX namespace pollution...
+ */
+#define cpu_to_le64 __cpu_to_le64
+#define le64_to_cpu __le64_to_cpu
+#define cpu_to_le32 __cpu_to_le32
+#define le32_to_cpu __le32_to_cpu
+#define cpu_to_le16 __cpu_to_le16
+#define le16_to_cpu __le16_to_cpu
+#define cpu_to_be64 __cpu_to_be64
+#define be64_to_cpu __be64_to_cpu
+#define cpu_to_be32 __cpu_to_be32
+#define be32_to_cpu __be32_to_cpu
+#define cpu_to_be16 __cpu_to_be16
+#define be16_to_cpu __be16_to_cpu
+#define cpu_to_le64p __cpu_to_le64p
+#define le64_to_cpup __le64_to_cpup
+#define cpu_to_le32p __cpu_to_le32p
+#define le32_to_cpup __le32_to_cpup
+#define cpu_to_le16p __cpu_to_le16p
+#define le16_to_cpup __le16_to_cpup
+#define cpu_to_be64p __cpu_to_be64p
+#define be64_to_cpup __be64_to_cpup
+#define cpu_to_be32p __cpu_to_be32p
+#define be32_to_cpup __be32_to_cpup
+#define cpu_to_be16p __cpu_to_be16p
+#define be16_to_cpup __be16_to_cpup
+#define cpu_to_le64s __cpu_to_le64s
+#define le64_to_cpus __le64_to_cpus
+#define cpu_to_le32s __cpu_to_le32s
+#define le32_to_cpus __le32_to_cpus
+#define cpu_to_le16s __cpu_to_le16s
+#define le16_to_cpus __le16_to_cpus
+#define cpu_to_be64s __cpu_to_be64s
+#define be64_to_cpus __be64_to_cpus
+#define cpu_to_be32s __cpu_to_be32s
+#define be32_to_cpus __be32_to_cpus
+#define cpu_to_be16s __cpu_to_be16s
+#define be16_to_cpus __be16_to_cpus
+#endif
+
+
+#if defined(__KERNEL__)
+/*
+ * Handle ntohl and suches. These have various compatibility
+ * issues - like we want to give the prototype even though we
+ * also have a macro for them in case some strange program
+ * wants to take the address of the thing or something..
+ *
+ * Note that these used to return a "long" in libc5, even though
+ * long is often 64-bit these days.. Thus the casts.
+ *
+ * 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
+
+/*
+ * Do the prototypes. Somebody might want to take the
+ * address or some such sick thing..
+ */
+extern __u32                    ntohl(__be32);
+extern __be32                   htonl(__u32);
+extern __u16                    ntohs(__be16);
+extern __be16                   htons(__u16);
+
+#if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)
+
+#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)
+
+#endif /* OPTIMIZE */
+
+#endif /* KERNEL */
+
+
+#endif /* _LINUX_BYTEORDER_GENERIC_H */