1#ifndef _LINUX_SWAB_H 2#define _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#ifdef __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#ifdef __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#ifdef __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#define __swab16(x) \ 100 (__builtin_constant_p((__u16)(x)) ? \ 101 ___constant_swab16(x) : \ 102 __fswab16(x)) 103 104/** 105 * __swab32 - return a byteswapped 32-bit value 106 * @x: value to byteswap 107 */ 108#define __swab32(x) \ 109 (__builtin_constant_p((__u32)(x)) ? \ 110 ___constant_swab32(x) : \ 111 __fswab32(x)) 112 113/** 114 * __swab64 - return a byteswapped 64-bit value 115 * @x: value to byteswap 116 */ 117#define __swab64(x) \ 118 (__builtin_constant_p((__u64)(x)) ? \ 119 ___constant_swab64(x) : \ 120 __fswab64(x)) 121 122/** 123 * __swahw32 - return a word-swapped 32-bit value 124 * @x: value to wordswap 125 * 126 * __swahw32(0x12340000) is 0x00001234 127 */ 128#define __swahw32(x) \ 129 (__builtin_constant_p((__u32)(x)) ? \ 130 ___constant_swahw32(x) : \ 131 __fswahw32(x)) 132 133/** 134 * __swahb32 - return a high and low byte-swapped 32-bit value 135 * @x: value to byteswap 136 * 137 * __swahb32(0x12345678) is 0x34127856 138 */ 139#define __swahb32(x) \ 140 (__builtin_constant_p((__u32)(x)) ? \ 141 ___constant_swahb32(x) : \ 142 __fswahb32(x)) 143 144/** 145 * __swab16p - return a byteswapped 16-bit value from a pointer 146 * @p: pointer to a naturally-aligned 16-bit value 147 */ 148static inline __u16 __swab16p(const __u16 *p) 149{ 150#ifdef __arch_swab16p 151 return __arch_swab16p(p); 152#else 153 return __swab16(*p); 154#endif 155} 156 157/** 158 * __swab32p - return a byteswapped 32-bit value from a pointer 159 * @p: pointer to a naturally-aligned 32-bit value 160 */ 161static inline __u32 __swab32p(const __u32 *p) 162{ 163#ifdef __arch_swab32p 164 return __arch_swab32p(p); 165#else 166 return __swab32(*p); 167#endif 168} 169 170/** 171 * __swab64p - return a byteswapped 64-bit value from a pointer 172 * @p: pointer to a naturally-aligned 64-bit value 173 */ 174static inline __u64 __swab64p(const __u64 *p) 175{ 176#ifdef __arch_swab64p 177 return __arch_swab64p(p); 178#else 179 return __swab64(*p); 180#endif 181} 182 183/** 184 * __swahw32p - return a wordswapped 32-bit value from a pointer 185 * @p: pointer to a naturally-aligned 32-bit value 186 * 187 * See __swahw32() for details of wordswapping. 188 */ 189static inline __u32 __swahw32p(const __u32 *p) 190{ 191#ifdef __arch_swahw32p 192 return __arch_swahw32p(p); 193#else 194 return __swahw32(*p); 195#endif 196} 197 198/** 199 * __swahb32p - return a high and low byteswapped 32-bit value from a pointer 200 * @p: pointer to a naturally-aligned 32-bit value 201 * 202 * See __swahb32() for details of high/low byteswapping. 203 */ 204static inline __u32 __swahb32p(const __u32 *p) 205{ 206#ifdef __arch_swahb32p 207 return __arch_swahb32p(p); 208#else 209 return __swahb32(*p); 210#endif 211} 212 213/** 214 * __swab16s - byteswap a 16-bit value in-place 215 * @p: pointer to a naturally-aligned 16-bit value 216 */ 217static inline void __swab16s(__u16 *p) 218{ 219#ifdef __arch_swab16s 220 __arch_swab16s(p); 221#else 222 *p = __swab16p(p); 223#endif 224} 225/** 226 * __swab32s - byteswap a 32-bit value in-place 227 * @p: pointer to a naturally-aligned 32-bit value 228 */ 229static inline void __swab32s(__u32 *p) 230{ 231#ifdef __arch_swab32s 232 __arch_swab32s(p); 233#else 234 *p = __swab32p(p); 235#endif 236} 237 238/** 239 * __swab64s - byteswap a 64-bit value in-place 240 * @p: pointer to a naturally-aligned 64-bit value 241 */ 242static inline void __swab64s(__u64 *p) 243{ 244#ifdef __arch_swab64s 245 __arch_swab64s(p); 246#else 247 *p = __swab64p(p); 248#endif 249} 250 251/** 252 * __swahw32s - wordswap a 32-bit value in-place 253 * @p: pointer to a naturally-aligned 32-bit value 254 * 255 * See __swahw32() for details of wordswapping 256 */ 257static inline void __swahw32s(__u32 *p) 258{ 259#ifdef __arch_swahw32s 260 __arch_swahw32s(p); 261#else 262 *p = __swahw32p(p); 263#endif 264} 265 266/** 267 * __swahb32s - high and low byteswap a 32-bit value in-place 268 * @p: pointer to a naturally-aligned 32-bit value 269 * 270 * See __swahb32() for details of high and low byte swapping 271 */ 272static inline void __swahb32s(__u32 *p) 273{ 274#ifdef __arch_swahb32s 275 __arch_swahb32s(p); 276#else 277 *p = __swahb32p(p); 278#endif 279} 280 281#ifdef __KERNEL__ 282# define swab16 __swab16 283# define swab32 __swab32 284# define swab64 __swab64 285# define swahw32 __swahw32 286# define swahb32 __swahb32 287# define swab16p __swab16p 288# define swab32p __swab32p 289# define swab64p __swab64p 290# define swahw32p __swahw32p 291# define swahb32p __swahb32p 292# define swab16s __swab16s 293# define swab32s __swab32s 294# define swab64s __swab64s 295# define swahw32s __swahw32s 296# define swahb32s __swahb32s 297#endif /* __KERNEL__ */ 298 299#endif /* _LINUX_SWAB_H */ 300