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1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */2#ifndef _UAPI_LINUX_SWAB_H3#define _UAPI_LINUX_SWAB_H4 5#include <linux/types.h>6#include <linux/stddef.h>7#include <asm/bitsperlong.h>8#include <asm/swab.h>9 10/*11 * casts are necessary for constants, because we never know how for sure12 * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way.13 */14#define ___constant_swab16(x) ((__u16)( \15 (((__u16)(x) & (__u16)0x00ffU) << 8) | \16 (((__u16)(x) & (__u16)0xff00U) >> 8)))17 18#define ___constant_swab32(x) ((__u32)( \19 (((__u32)(x) & (__u32)0x000000ffUL) << 24) | \20 (((__u32)(x) & (__u32)0x0000ff00UL) << 8) | \21 (((__u32)(x) & (__u32)0x00ff0000UL) >> 8) | \22 (((__u32)(x) & (__u32)0xff000000UL) >> 24)))23 24#define ___constant_swab64(x) ((__u64)( \25 (((__u64)(x) & (__u64)0x00000000000000ffULL) << 56) | \26 (((__u64)(x) & (__u64)0x000000000000ff00ULL) << 40) | \27 (((__u64)(x) & (__u64)0x0000000000ff0000ULL) << 24) | \28 (((__u64)(x) & (__u64)0x00000000ff000000ULL) << 8) | \29 (((__u64)(x) & (__u64)0x000000ff00000000ULL) >> 8) | \30 (((__u64)(x) & (__u64)0x0000ff0000000000ULL) >> 24) | \31 (((__u64)(x) & (__u64)0x00ff000000000000ULL) >> 40) | \32 (((__u64)(x) & (__u64)0xff00000000000000ULL) >> 56)))33 34#define ___constant_swahw32(x) ((__u32)( \35 (((__u32)(x) & (__u32)0x0000ffffUL) << 16) | \36 (((__u32)(x) & (__u32)0xffff0000UL) >> 16)))37 38#define ___constant_swahb32(x) ((__u32)( \39 (((__u32)(x) & (__u32)0x00ff00ffUL) << 8) | \40 (((__u32)(x) & (__u32)0xff00ff00UL) >> 8)))41 42/*43 * Implement the following as inlines, but define the interface using44 * macros to allow constant folding when possible:45 * ___swab16, ___swab32, ___swab64, ___swahw32, ___swahb3246 */47 48static inline __attribute_const__ __u16 __fswab16(__u16 val)49{50#if defined (__arch_swab16)51 return __arch_swab16(val);52#else53 return ___constant_swab16(val);54#endif55}56 57static inline __attribute_const__ __u32 __fswab32(__u32 val)58{59#if defined(__arch_swab32)60 return __arch_swab32(val);61#else62 return ___constant_swab32(val);63#endif64}65 66static inline __attribute_const__ __u64 __fswab64(__u64 val)67{68#if defined (__arch_swab64)69 return __arch_swab64(val);70#elif defined(__SWAB_64_THRU_32__)71 __u32 h = val >> 32;72 __u32 l = val & ((1ULL << 32) - 1);73 return (((__u64)__fswab32(l)) << 32) | ((__u64)(__fswab32(h)));74#else75 return ___constant_swab64(val);76#endif77}78 79static inline __attribute_const__ __u32 __fswahw32(__u32 val)80{81#ifdef __arch_swahw3282 return __arch_swahw32(val);83#else84 return ___constant_swahw32(val);85#endif86}87 88static inline __attribute_const__ __u32 __fswahb32(__u32 val)89{90#ifdef __arch_swahb3291 return __arch_swahb32(val);92#else93 return ___constant_swahb32(val);94#endif95}96 97/**98 * __swab16 - return a byteswapped 16-bit value99 * @x: value to byteswap100 */101#ifdef __HAVE_BUILTIN_BSWAP16__102#define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))103#else104#define __swab16(x) \105 (__u16)(__builtin_constant_p(x) ? \106 ___constant_swab16(x) : \107 __fswab16(x))108#endif109 110/**111 * __swab32 - return a byteswapped 32-bit value112 * @x: value to byteswap113 */114#ifdef __HAVE_BUILTIN_BSWAP32__115#define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))116#else117#define __swab32(x) \118 (__u32)(__builtin_constant_p(x) ? \119 ___constant_swab32(x) : \120 __fswab32(x))121#endif122 123/**124 * __swab64 - return a byteswapped 64-bit value125 * @x: value to byteswap126 */127#ifdef __HAVE_BUILTIN_BSWAP64__128#define __swab64(x) (__u64)__builtin_bswap64((__u64)(x))129#else130#define __swab64(x) \131 (__u64)(__builtin_constant_p(x) ? \132 ___constant_swab64(x) : \133 __fswab64(x))134#endif135 136static __always_inline unsigned long __swab(const unsigned long y)137{138#if __BITS_PER_LONG == 64139 return __swab64(y);140#else /* __BITS_PER_LONG == 32 */141 return __swab32(y);142#endif143}144 145/**146 * __swahw32 - return a word-swapped 32-bit value147 * @x: value to wordswap148 *149 * __swahw32(0x12340000) is 0x00001234150 */151#define __swahw32(x) \152 (__builtin_constant_p((__u32)(x)) ? \153 ___constant_swahw32(x) : \154 __fswahw32(x))155 156/**157 * __swahb32 - return a high and low byte-swapped 32-bit value158 * @x: value to byteswap159 *160 * __swahb32(0x12345678) is 0x34127856161 */162#define __swahb32(x) \163 (__builtin_constant_p((__u32)(x)) ? \164 ___constant_swahb32(x) : \165 __fswahb32(x))166 167/**168 * __swab16p - return a byteswapped 16-bit value from a pointer169 * @p: pointer to a naturally-aligned 16-bit value170 */171static __always_inline __u16 __swab16p(const __u16 *p)172{173#ifdef __arch_swab16p174 return __arch_swab16p(p);175#else176 return __swab16(*p);177#endif178}179 180/**181 * __swab32p - return a byteswapped 32-bit value from a pointer182 * @p: pointer to a naturally-aligned 32-bit value183 */184static __always_inline __u32 __swab32p(const __u32 *p)185{186#ifdef __arch_swab32p187 return __arch_swab32p(p);188#else189 return __swab32(*p);190#endif191}192 193/**194 * __swab64p - return a byteswapped 64-bit value from a pointer195 * @p: pointer to a naturally-aligned 64-bit value196 */197static __always_inline __u64 __swab64p(const __u64 *p)198{199#ifdef __arch_swab64p200 return __arch_swab64p(p);201#else202 return __swab64(*p);203#endif204}205 206/**207 * __swahw32p - return a wordswapped 32-bit value from a pointer208 * @p: pointer to a naturally-aligned 32-bit value209 *210 * See __swahw32() for details of wordswapping.211 */212static inline __u32 __swahw32p(const __u32 *p)213{214#ifdef __arch_swahw32p215 return __arch_swahw32p(p);216#else217 return __swahw32(*p);218#endif219}220 221/**222 * __swahb32p - return a high and low byteswapped 32-bit value from a pointer223 * @p: pointer to a naturally-aligned 32-bit value224 *225 * See __swahb32() for details of high/low byteswapping.226 */227static inline __u32 __swahb32p(const __u32 *p)228{229#ifdef __arch_swahb32p230 return __arch_swahb32p(p);231#else232 return __swahb32(*p);233#endif234}235 236/**237 * __swab16s - byteswap a 16-bit value in-place238 * @p: pointer to a naturally-aligned 16-bit value239 */240static inline void __swab16s(__u16 *p)241{242#ifdef __arch_swab16s243 __arch_swab16s(p);244#else245 *p = __swab16p(p);246#endif247}248/**249 * __swab32s - byteswap a 32-bit value in-place250 * @p: pointer to a naturally-aligned 32-bit value251 */252static __always_inline void __swab32s(__u32 *p)253{254#ifdef __arch_swab32s255 __arch_swab32s(p);256#else257 *p = __swab32p(p);258#endif259}260 261/**262 * __swab64s - byteswap a 64-bit value in-place263 * @p: pointer to a naturally-aligned 64-bit value264 */265static __always_inline void __swab64s(__u64 *p)266{267#ifdef __arch_swab64s268 __arch_swab64s(p);269#else270 *p = __swab64p(p);271#endif272}273 274/**275 * __swahw32s - wordswap a 32-bit value in-place276 * @p: pointer to a naturally-aligned 32-bit value277 *278 * See __swahw32() for details of wordswapping279 */280static inline void __swahw32s(__u32 *p)281{282#ifdef __arch_swahw32s283 __arch_swahw32s(p);284#else285 *p = __swahw32p(p);286#endif287}288 289/**290 * __swahb32s - high and low byteswap a 32-bit value in-place291 * @p: pointer to a naturally-aligned 32-bit value292 *293 * See __swahb32() for details of high and low byte swapping294 */295static inline void __swahb32s(__u32 *p)296{297#ifdef __arch_swahb32s298 __arch_swahb32s(p);299#else300 *p = __swahb32p(p);301#endif302}303 304 305#endif /* _UAPI_LINUX_SWAB_H */306