1 | /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ |
2 | #ifndef _LINUX_SWAB_H |
3 | #define _LINUX_SWAB_H |
4 | |
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 sure |
12 | * 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 using |
44 | * macros to allow constant folding when possible: |
45 | * ___swab16, ___swab32, ___swab64, ___swahw32, ___swahb32 |
46 | */ |
47 | |
48 | static __inline__ __u16 __fswab16(__u16 val) |
49 | { |
50 | #if defined (__arch_swab16) |
51 | return __arch_swab16(val); |
52 | #else |
53 | return ___constant_swab16(val); |
54 | #endif |
55 | } |
56 | |
57 | static __inline__ __u32 __fswab32(__u32 val) |
58 | { |
59 | #if defined(__arch_swab32) |
60 | return __arch_swab32(val); |
61 | #else |
62 | return ___constant_swab32(val); |
63 | #endif |
64 | } |
65 | |
66 | static __inline__ __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 | #else |
75 | return ___constant_swab64(val); |
76 | #endif |
77 | } |
78 | |
79 | static __inline__ __u32 __fswahw32(__u32 val) |
80 | { |
81 | #ifdef __arch_swahw32 |
82 | return __arch_swahw32(val); |
83 | #else |
84 | return ___constant_swahw32(val); |
85 | #endif |
86 | } |
87 | |
88 | static __inline__ __u32 __fswahb32(__u32 val) |
89 | { |
90 | #ifdef __arch_swahb32 |
91 | return __arch_swahb32(val); |
92 | #else |
93 | return ___constant_swahb32(val); |
94 | #endif |
95 | } |
96 | |
97 | /** |
98 | * __swab16 - return a byteswapped 16-bit value |
99 | * @x: value to byteswap |
100 | */ |
101 | #ifdef __HAVE_BUILTIN_BSWAP16__ |
102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) |
103 | #else |
104 | #define __swab16(x) \ |
105 | (__builtin_constant_p((__u16)(x)) ? \ |
106 | ___constant_swab16(x) : \ |
107 | __fswab16(x)) |
108 | #endif |
109 | |
110 | /** |
111 | * __swab32 - return a byteswapped 32-bit value |
112 | * @x: value to byteswap |
113 | */ |
114 | #ifdef __HAVE_BUILTIN_BSWAP32__ |
115 | #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) |
116 | #else |
117 | #define __swab32(x) \ |
118 | (__builtin_constant_p((__u32)(x)) ? \ |
119 | ___constant_swab32(x) : \ |
120 | __fswab32(x)) |
121 | #endif |
122 | |
123 | /** |
124 | * __swab64 - return a byteswapped 64-bit value |
125 | * @x: value to byteswap |
126 | */ |
127 | #ifdef __HAVE_BUILTIN_BSWAP64__ |
128 | #define __swab64(x) (__u64)__builtin_bswap64((__u64)(x)) |
129 | #else |
130 | #define __swab64(x) \ |
131 | (__builtin_constant_p((__u64)(x)) ? \ |
132 | ___constant_swab64(x) : \ |
133 | __fswab64(x)) |
134 | #endif |
135 | |
136 | static __always_inline unsigned long __swab(const unsigned long y) |
137 | { |
138 | #if __BITS_PER_LONG == 64 |
139 | return __swab64(y); |
140 | #else /* __BITS_PER_LONG == 32 */ |
141 | return __swab32(y); |
142 | #endif |
143 | } |
144 | |
145 | /** |
146 | * __swahw32 - return a word-swapped 32-bit value |
147 | * @x: value to wordswap |
148 | * |
149 | * __swahw32(0x12340000) is 0x00001234 |
150 | */ |
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 value |
158 | * @x: value to byteswap |
159 | * |
160 | * __swahb32(0x12345678) is 0x34127856 |
161 | */ |
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 pointer |
169 | * @p: pointer to a naturally-aligned 16-bit value |
170 | */ |
171 | static __always_inline __u16 __swab16p(const __u16 *p) |
172 | { |
173 | #ifdef __arch_swab16p |
174 | return __arch_swab16p(p); |
175 | #else |
176 | return __swab16(*p); |
177 | #endif |
178 | } |
179 | |
180 | /** |
181 | * __swab32p - return a byteswapped 32-bit value from a pointer |
182 | * @p: pointer to a naturally-aligned 32-bit value |
183 | */ |
184 | static __always_inline __u32 __swab32p(const __u32 *p) |
185 | { |
186 | #ifdef __arch_swab32p |
187 | return __arch_swab32p(p); |
188 | #else |
189 | return __swab32(*p); |
190 | #endif |
191 | } |
192 | |
193 | /** |
194 | * __swab64p - return a byteswapped 64-bit value from a pointer |
195 | * @p: pointer to a naturally-aligned 64-bit value |
196 | */ |
197 | static __always_inline __u64 __swab64p(const __u64 *p) |
198 | { |
199 | #ifdef __arch_swab64p |
200 | return __arch_swab64p(p); |
201 | #else |
202 | return __swab64(*p); |
203 | #endif |
204 | } |
205 | |
206 | /** |
207 | * __swahw32p - return a wordswapped 32-bit value from a pointer |
208 | * @p: pointer to a naturally-aligned 32-bit value |
209 | * |
210 | * See __swahw32() for details of wordswapping. |
211 | */ |
212 | static __inline__ __u32 __swahw32p(const __u32 *p) |
213 | { |
214 | #ifdef __arch_swahw32p |
215 | return __arch_swahw32p(p); |
216 | #else |
217 | return __swahw32(*p); |
218 | #endif |
219 | } |
220 | |
221 | /** |
222 | * __swahb32p - return a high and low byteswapped 32-bit value from a pointer |
223 | * @p: pointer to a naturally-aligned 32-bit value |
224 | * |
225 | * See __swahb32() for details of high/low byteswapping. |
226 | */ |
227 | static __inline__ __u32 __swahb32p(const __u32 *p) |
228 | { |
229 | #ifdef __arch_swahb32p |
230 | return __arch_swahb32p(p); |
231 | #else |
232 | return __swahb32(*p); |
233 | #endif |
234 | } |
235 | |
236 | /** |
237 | * __swab16s - byteswap a 16-bit value in-place |
238 | * @p: pointer to a naturally-aligned 16-bit value |
239 | */ |
240 | static __inline__ void __swab16s(__u16 *p) |
241 | { |
242 | #ifdef __arch_swab16s |
243 | __arch_swab16s(p); |
244 | #else |
245 | *p = __swab16p(p); |
246 | #endif |
247 | } |
248 | /** |
249 | * __swab32s - byteswap a 32-bit value in-place |
250 | * @p: pointer to a naturally-aligned 32-bit value |
251 | */ |
252 | static __always_inline void __swab32s(__u32 *p) |
253 | { |
254 | #ifdef __arch_swab32s |
255 | __arch_swab32s(p); |
256 | #else |
257 | *p = __swab32p(p); |
258 | #endif |
259 | } |
260 | |
261 | /** |
262 | * __swab64s - byteswap a 64-bit value in-place |
263 | * @p: pointer to a naturally-aligned 64-bit value |
264 | */ |
265 | static __always_inline void __swab64s(__u64 *p) |
266 | { |
267 | #ifdef __arch_swab64s |
268 | __arch_swab64s(p); |
269 | #else |
270 | *p = __swab64p(p); |
271 | #endif |
272 | } |
273 | |
274 | /** |
275 | * __swahw32s - wordswap a 32-bit value in-place |
276 | * @p: pointer to a naturally-aligned 32-bit value |
277 | * |
278 | * See __swahw32() for details of wordswapping |
279 | */ |
280 | static __inline__ void __swahw32s(__u32 *p) |
281 | { |
282 | #ifdef __arch_swahw32s |
283 | __arch_swahw32s(p); |
284 | #else |
285 | *p = __swahw32p(p); |
286 | #endif |
287 | } |
288 | |
289 | /** |
290 | * __swahb32s - high and low byteswap a 32-bit value in-place |
291 | * @p: pointer to a naturally-aligned 32-bit value |
292 | * |
293 | * See __swahb32() for details of high and low byte swapping |
294 | */ |
295 | static __inline__ void __swahb32s(__u32 *p) |
296 | { |
297 | #ifdef __arch_swahb32s |
298 | __arch_swahb32s(p); |
299 | #else |
300 | *p = __swahb32p(p); |
301 | #endif |
302 | } |
303 | |
304 | |
305 | #endif /* _LINUX_SWAB_H */ |
306 | |