4 #include <linux/types.h>
5 #include <linux/compiler.h>
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.
12 #define ___constant_swab16(x) ((__u16)( \
13 (((__u16)(x) & (__u16)0x00ffU) << 8) | \
14 (((__u16)(x) & (__u16)0xff00U) >> 8)))
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)))
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)))
32 #define ___constant_swahw32(x) ((__u32)( \
33 (((__u32)(x) & (__u32)0x0000ffffUL) << 16) | \
34 (((__u32)(x) & (__u32)0xffff0000UL) >> 16)))
36 #define ___constant_swahb32(x) ((__u32)( \
37 (((__u32)(x) & (__u32)0x00ff00ffUL) << 8) | \
38 (((__u32)(x) & (__u32)0xff00ff00UL) >> 8)))
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
46 static inline __attribute_const__ __u16 __fswab16(__u16 val)
49 return __arch_swab16(val);
51 return ___constant_swab16(val);
55 static inline __attribute_const__ __u32 __fswab32(__u32 val)
58 return __arch_swab32(val);
60 return ___constant_swab32(val);
64 static inline __attribute_const__ __u64 __fswab64(__u64 val)
67 return __arch_swab64(val);
68 #elif defined(__SWAB_64_THRU_32__)
70 __u32 l = val & ((1ULL << 32) - 1);
71 return (((__u64)__fswab32(l)) << 32) | ((__u64)(__fswab32(h)));
73 return ___constant_swab64(val);
77 static inline __attribute_const__ __u32 __fswahw32(__u32 val)
80 return __arch_swahw32(val);
82 return ___constant_swahw32(val);
86 static inline __attribute_const__ __u32 __fswahb32(__u32 val)
89 return __arch_swahb32(val);
91 return ___constant_swahb32(val);
96 * __swab16 - return a byteswapped 16-bit value
97 * @x: value to byteswap
100 (__builtin_constant_p((__u16)(x)) ? \
101 ___constant_swab16(x) : \
105 * __swab32 - return a byteswapped 32-bit value
106 * @x: value to byteswap
108 #define __swab32(x) \
109 (__builtin_constant_p((__u32)(x)) ? \
110 ___constant_swab32(x) : \
114 * __swab64 - return a byteswapped 64-bit value
115 * @x: value to byteswap
117 #define __swab64(x) \
118 (__builtin_constant_p((__u64)(x)) ? \
119 ___constant_swab64(x) : \
123 * __swahw32 - return a word-swapped 32-bit value
124 * @x: value to wordswap
126 * __swahw32(0x12340000) is 0x00001234
128 #define __swahw32(x) \
129 (__builtin_constant_p((__u32)(x)) ? \
130 ___constant_swahw32(x) : \
134 * __swahb32 - return a high and low byte-swapped 32-bit value
135 * @x: value to byteswap
137 * __swahb32(0x12345678) is 0x34127856
139 #define __swahb32(x) \
140 (__builtin_constant_p((__u32)(x)) ? \
141 ___constant_swahb32(x) : \
145 * __swab16p - return a byteswapped 16-bit value from a pointer
146 * @p: pointer to a naturally-aligned 16-bit value
148 static inline __u16 __swab16p(const __u16 *p)
150 #ifdef __arch_swab16p
151 return __arch_swab16p(p);
158 * __swab32p - return a byteswapped 32-bit value from a pointer
159 * @p: pointer to a naturally-aligned 32-bit value
161 static inline __u32 __swab32p(const __u32 *p)
163 #ifdef __arch_swab32p
164 return __arch_swab32p(p);
171 * __swab64p - return a byteswapped 64-bit value from a pointer
172 * @p: pointer to a naturally-aligned 64-bit value
174 static inline __u64 __swab64p(const __u64 *p)
176 #ifdef __arch_swab64p
177 return __arch_swab64p(p);
184 * __swahw32p - return a wordswapped 32-bit value from a pointer
185 * @p: pointer to a naturally-aligned 32-bit value
187 * See __swahw32() for details of wordswapping.
189 static inline __u32 __swahw32p(const __u32 *p)
191 #ifdef __arch_swahw32p
192 return __arch_swahw32p(p);
194 return __swahw32(*p);
199 * __swahb32p - return a high and low byteswapped 32-bit value from a pointer
200 * @p: pointer to a naturally-aligned 32-bit value
202 * See __swahb32() for details of high/low byteswapping.
204 static inline __u32 __swahb32p(const __u32 *p)
206 #ifdef __arch_swahb32p
207 return __arch_swahb32p(p);
209 return __swahb32(*p);
214 * __swab16s - byteswap a 16-bit value in-place
215 * @p: pointer to a naturally-aligned 16-bit value
217 static inline void __swab16s(__u16 *p)
219 #ifdef __arch_swab16s
226 * __swab32s - byteswap a 32-bit value in-place
227 * @p: pointer to a naturally-aligned 32-bit value
229 static inline void __swab32s(__u32 *p)
231 #ifdef __arch_swab32s
239 * __swab64s - byteswap a 64-bit value in-place
240 * @p: pointer to a naturally-aligned 64-bit value
242 static inline void __swab64s(__u64 *p)
244 #ifdef __arch_swab64s
252 * __swahw32s - wordswap a 32-bit value in-place
253 * @p: pointer to a naturally-aligned 32-bit value
255 * See __swahw32() for details of wordswapping
257 static inline void __swahw32s(__u32 *p)
259 #ifdef __arch_swahw32s
267 * __swahb32s - high and low byteswap a 32-bit value in-place
268 * @p: pointer to a naturally-aligned 32-bit value
270 * See __swahb32() for details of high and low byte swapping
272 static inline void __swahb32s(__u32 *p)
274 #ifdef __arch_swahb32s
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__ */
299 #endif /* _LINUX_SWAB_H */