1#ifndef _UAPI_LINUX_SWAB_H 2#define _UAPI_LINUX_SWAB_H 3 4#include <linux/types.h> 5#include <linux/compiler.h> 6#include <asm/swab.h> 7 8/* 9 * casts are necessary for constants, because we never know how for sure 10 * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way. 11 */ 12#define ___constant_swab16(x) ((__u16)( \ 13 (((__u16)(x) & (__u16)0x00ffU) << 8) | \ 14 (((__u16)(x) & (__u16)0xff00U) >> 8))) 15 16#define ___constant_swab32(x) ((__u32)( \ 17 (((__u32)(x) & (__u32)0x000000ffUL) << 24) | \ 18 (((__u32)(x) & (__u32)0x0000ff00UL) << 8) | \ 19 (((__u32)(x) & (__u32)0x00ff0000UL) >> 8) | \ 20 (((__u32)(x) & (__u32)0xff000000UL) >> 24))) 21 22#define ___constant_swab64(x) ((__u64)( \ 23 (((__u64)(x) & (__u64)0x00000000000000ffULL) << 56) | \ 24 (((__u64)(x) & (__u64)0x000000000000ff00ULL) << 40) | \ 25 (((__u64)(x) & (__u64)0x0000000000ff0000ULL) << 24) | \ 26 (((__u64)(x) & (__u64)0x00000000ff000000ULL) << 8) | \ 27 (((__u64)(x) & (__u64)0x000000ff00000000ULL) >> 8) | \ 28 (((__u64)(x) & (__u64)0x0000ff0000000000ULL) >> 24) | \ 29 (((__u64)(x) & (__u64)0x00ff000000000000ULL) >> 40) | \ 30 (((__u64)(x) & (__u64)0xff00000000000000ULL) >> 56))) 31 32#define ___constant_swahw32(x) ((__u32)( \ 33 (((__u32)(x) & (__u32)0x0000ffffUL) << 16) | \ 34 (((__u32)(x) & (__u32)0xffff0000UL) >> 16))) 35 36#define ___constant_swahb32(x) ((__u32)( \ 37 (((__u32)(x) & (__u32)0x00ff00ffUL) << 8) | \ 38 (((__u32)(x) & (__u32)0xff00ff00UL) >> 8))) 39 40/* 41 * Implement the following as inlines, but define the interface using 42 * macros to allow constant folding when possible: 43 * ___swab16, ___swab32, ___swab64, ___swahw32, ___swahb32 44 */ 45 46static inline __attribute_const__ __u16 __fswab16(__u16 val) 47{ 48#if defined (__arch_swab16) 49 return __arch_swab16(val); 50#else 51 return ___constant_swab16(val); 52#endif 53} 54 55static inline __attribute_const__ __u32 __fswab32(__u32 val) 56{ 57#if defined(__arch_swab32) 58 return __arch_swab32(val); 59#else 60 return ___constant_swab32(val); 61#endif 62} 63 64static inline __attribute_const__ __u64 __fswab64(__u64 val) 65{ 66#if defined (__arch_swab64) 67 return __arch_swab64(val); 68#elif defined(__SWAB_64_THRU_32__) 69 __u32 h = val >> 32; 70 __u32 l = val & ((1ULL << 32) - 1); 71 return (((__u64)__fswab32(l)) << 32) | ((__u64)(__fswab32(h))); 72#else 73 return ___constant_swab64(val); 74#endif 75} 76 77static inline __attribute_const__ __u32 __fswahw32(__u32 val) 78{ 79#ifdef __arch_swahw32 80 return __arch_swahw32(val); 81#else 82 return ___constant_swahw32(val); 83#endif 84} 85 86static inline __attribute_const__ __u32 __fswahb32(__u32 val) 87{ 88#ifdef __arch_swahb32 89 return __arch_swahb32(val); 90#else 91 return ___constant_swahb32(val); 92#endif 93} 94 95/** 96 * __swab16 - return a byteswapped 16-bit value 97 * @x: value to byteswap 98 */ 99#ifdef __HAVE_BUILTIN_BSWAP16__ 100#define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) 101#else 102#define __swab16(x) \ 103 (__builtin_constant_p((__u16)(x)) ? \ 104 ___constant_swab16(x) : \ 105 __fswab16(x)) 106#endif 107 108/** 109 * __swab32 - return a byteswapped 32-bit value 110 * @x: value to byteswap 111 */ 112#ifdef __HAVE_BUILTIN_BSWAP32__ 113#define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) 114#else 115#define __swab32(x) \ 116 (__builtin_constant_p((__u32)(x)) ? \ 117 ___constant_swab32(x) : \ 118 __fswab32(x)) 119#endif 120 121/** 122 * __swab64 - return a byteswapped 64-bit value 123 * @x: value to byteswap 124 */ 125#ifdef __HAVE_BUILTIN_BSWAP64__ 126#define __swab64(x) (__u64)__builtin_bswap64((__u64)(x)) 127#else 128#define __swab64(x) \ 129 (__builtin_constant_p((__u64)(x)) ? \ 130 ___constant_swab64(x) : \ 131 __fswab64(x)) 132#endif 133 134/** 135 * __swahw32 - return a word-swapped 32-bit value 136 * @x: value to wordswap 137 * 138 * __swahw32(0x12340000) is 0x00001234 139 */ 140#define __swahw32(x) \ 141 (__builtin_constant_p((__u32)(x)) ? \ 142 ___constant_swahw32(x) : \ 143 __fswahw32(x)) 144 145/** 146 * __swahb32 - return a high and low byte-swapped 32-bit value 147 * @x: value to byteswap 148 * 149 * __swahb32(0x12345678) is 0x34127856 150 */ 151#define __swahb32(x) \ 152 (__builtin_constant_p((__u32)(x)) ? \ 153 ___constant_swahb32(x) : \ 154 __fswahb32(x)) 155 156/** 157 * __swab16p - return a byteswapped 16-bit value from a pointer 158 * @p: pointer to a naturally-aligned 16-bit value 159 */ 160static __always_inline __u16 __swab16p(const __u16 *p) 161{ 162#ifdef __arch_swab16p 163 return __arch_swab16p(p); 164#else 165 return __swab16(*p); 166#endif 167} 168 169/** 170 * __swab32p - return a byteswapped 32-bit value from a pointer 171 * @p: pointer to a naturally-aligned 32-bit value 172 */ 173static __always_inline __u32 __swab32p(const __u32 *p) 174{ 175#ifdef __arch_swab32p 176 return __arch_swab32p(p); 177#else 178 return __swab32(*p); 179#endif 180} 181 182/** 183 * __swab64p - return a byteswapped 64-bit value from a pointer 184 * @p: pointer to a naturally-aligned 64-bit value 185 */ 186static __always_inline __u64 __swab64p(const __u64 *p) 187{ 188#ifdef __arch_swab64p 189 return __arch_swab64p(p); 190#else 191 return __swab64(*p); 192#endif 193} 194 195/** 196 * __swahw32p - return a wordswapped 32-bit value from a pointer 197 * @p: pointer to a naturally-aligned 32-bit value 198 * 199 * See __swahw32() for details of wordswapping. 200 */ 201static inline __u32 __swahw32p(const __u32 *p) 202{ 203#ifdef __arch_swahw32p 204 return __arch_swahw32p(p); 205#else 206 return __swahw32(*p); 207#endif 208} 209 210/** 211 * __swahb32p - return a high and low byteswapped 32-bit value from a pointer 212 * @p: pointer to a naturally-aligned 32-bit value 213 * 214 * See __swahb32() for details of high/low byteswapping. 215 */ 216static inline __u32 __swahb32p(const __u32 *p) 217{ 218#ifdef __arch_swahb32p 219 return __arch_swahb32p(p); 220#else 221 return __swahb32(*p); 222#endif 223} 224 225/** 226 * __swab16s - byteswap a 16-bit value in-place 227 * @p: pointer to a naturally-aligned 16-bit value 228 */ 229static inline void __swab16s(__u16 *p) 230{ 231#ifdef __arch_swab16s 232 __arch_swab16s(p); 233#else 234 *p = __swab16p(p); 235#endif 236} 237/** 238 * __swab32s - byteswap a 32-bit value in-place 239 * @p: pointer to a naturally-aligned 32-bit value 240 */ 241static __always_inline void __swab32s(__u32 *p) 242{ 243#ifdef __arch_swab32s 244 __arch_swab32s(p); 245#else 246 *p = __swab32p(p); 247#endif 248} 249 250/** 251 * __swab64s - byteswap a 64-bit value in-place 252 * @p: pointer to a naturally-aligned 64-bit value 253 */ 254static __always_inline void __swab64s(__u64 *p) 255{ 256#ifdef __arch_swab64s 257 __arch_swab64s(p); 258#else 259 *p = __swab64p(p); 260#endif 261} 262 263/** 264 * __swahw32s - wordswap a 32-bit value in-place 265 * @p: pointer to a naturally-aligned 32-bit value 266 * 267 * See __swahw32() for details of wordswapping 268 */ 269static inline void __swahw32s(__u32 *p) 270{ 271#ifdef __arch_swahw32s 272 __arch_swahw32s(p); 273#else 274 *p = __swahw32p(p); 275#endif 276} 277 278/** 279 * __swahb32s - high and low byteswap a 32-bit value in-place 280 * @p: pointer to a naturally-aligned 32-bit value 281 * 282 * See __swahb32() for details of high and low byte swapping 283 */ 284static inline void __swahb32s(__u32 *p) 285{ 286#ifdef __arch_swahb32s 287 __arch_swahb32s(p); 288#else 289 *p = __swahb32p(p); 290#endif 291} 292 293 294#endif /* _UAPI_LINUX_SWAB_H */ 295