1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_BYTEORDER_GENERIC_H
3 #define _LINUX_BYTEORDER_GENERIC_H
4
5 /*
6 * linux/byteorder/generic.h
7 * Generic Byte-reordering support
8 *
9 * The "... p" macros, like le64_to_cpup, can be used with pointers
10 * to unaligned data, but there will be a performance penalty on
11 * some architectures. Use get_unaligned for unaligned data.
12 *
13 * Francois-Rene Rideau <fare@tunes.org> 19970707
14 * gathered all the good ideas from all asm-foo/byteorder.h into one file,
15 * cleaned them up.
16 * I hope it is compliant with non-GCC compilers.
17 * I decided to put __BYTEORDER_HAS_U64__ in byteorder.h,
18 * because I wasn't sure it would be ok to put it in types.h
19 * Upgraded it to 2.1.43
20 * Francois-Rene Rideau <fare@tunes.org> 19971012
21 * Upgraded it to 2.1.57
22 * to please Linus T., replaced huge #ifdef's between little/big endian
23 * by nestedly #include'd files.
24 * Francois-Rene Rideau <fare@tunes.org> 19971205
25 * Made it to 2.1.71; now a facelift:
26 * Put files under include/linux/byteorder/
27 * Split swab from generic support.
28 *
29 * TODO:
30 * = Regular kernel maintainers could also replace all these manual
31 * byteswap macros that remain, disseminated among drivers,
32 * after some grep or the sources...
33 * = Linus might want to rename all these macros and files to fit his taste,
34 * to fit his personal naming scheme.
35 * = it seems that a few drivers would also appreciate
36 * nybble swapping support...
37 * = every architecture could add their byteswap macro in asm/byteorder.h
38 * see how some architectures already do (i386, alpha, ppc, etc)
39 * = cpu_to_beXX and beXX_to_cpu might some day need to be well
40 * distinguished throughout the kernel. This is not the case currently,
41 * since little endian, big endian, and pdp endian machines needn't it.
42 * But this might be the case for, say, a port of Linux to 20/21 bit
43 * architectures (and F21 Linux addict around?).
44 */
45
46 /*
47 * The following macros are to be defined by <asm/byteorder.h>:
48 *
49 * Conversion of long and short int between network and host format
50 * ntohl(__u32 x)
51 * ntohs(__u16 x)
52 * htonl(__u32 x)
53 * htons(__u16 x)
54 * It seems that some programs (which? where? or perhaps a standard? POSIX?)
55 * might like the above to be functions, not macros (why?).
56 * if that's true, then detect them, and take measures.
57 * Anyway, the measure is: define only ___ntohl as a macro instead,
58 * and in a separate file, have
59 * unsigned long inline ntohl(x){return ___ntohl(x);}
60 *
61 * The same for constant arguments
62 * __constant_ntohl(__u32 x)
63 * __constant_ntohs(__u16 x)
64 * __constant_htonl(__u32 x)
65 * __constant_htons(__u16 x)
66 *
67 * Conversion of XX-bit integers (16- 32- or 64-)
68 * between native CPU format and little/big endian format
69 * 64-bit stuff only defined for proper architectures
70 * cpu_to_[bl]eXX(__uXX x)
71 * [bl]eXX_to_cpu(__uXX x)
72 *
73 * The same, but takes a pointer to the value to convert
74 * cpu_to_[bl]eXXp(__uXX x)
75 * [bl]eXX_to_cpup(__uXX x)
76 *
77 * The same, but change in situ
78 * cpu_to_[bl]eXXs(__uXX x)
79 * [bl]eXX_to_cpus(__uXX x)
80 *
81 * See asm-foo/byteorder.h for examples of how to provide
82 * architecture-optimized versions
83 *
84 */
85
86 #define cpu_to_le64 __cpu_to_le64
87 #define le64_to_cpu __le64_to_cpu
88 #define cpu_to_le32 __cpu_to_le32
89 #define le32_to_cpu __le32_to_cpu
90 #define cpu_to_le16 __cpu_to_le16
91 #define le16_to_cpu __le16_to_cpu
92 #define cpu_to_be64 __cpu_to_be64
93 #define be64_to_cpu __be64_to_cpu
94 #define cpu_to_be32 __cpu_to_be32
95 #define be32_to_cpu __be32_to_cpu
96 #define cpu_to_be16 __cpu_to_be16
97 #define be16_to_cpu __be16_to_cpu
98 #define cpu_to_le64p __cpu_to_le64p
99 #define le64_to_cpup __le64_to_cpup
100 #define cpu_to_le32p __cpu_to_le32p
101 #define le32_to_cpup __le32_to_cpup
102 #define cpu_to_le16p __cpu_to_le16p
103 #define le16_to_cpup __le16_to_cpup
104 #define cpu_to_be64p __cpu_to_be64p
105 #define be64_to_cpup __be64_to_cpup
106 #define cpu_to_be32p __cpu_to_be32p
107 #define be32_to_cpup __be32_to_cpup
108 #define cpu_to_be16p __cpu_to_be16p
109 #define be16_to_cpup __be16_to_cpup
110 #define cpu_to_le64s __cpu_to_le64s
111 #define le64_to_cpus __le64_to_cpus
112 #define cpu_to_le32s __cpu_to_le32s
113 #define le32_to_cpus __le32_to_cpus
114 #define cpu_to_le16s __cpu_to_le16s
115 #define le16_to_cpus __le16_to_cpus
116 #define cpu_to_be64s __cpu_to_be64s
117 #define be64_to_cpus __be64_to_cpus
118 #define cpu_to_be32s __cpu_to_be32s
119 #define be32_to_cpus __be32_to_cpus
120 #define cpu_to_be16s __cpu_to_be16s
121 #define be16_to_cpus __be16_to_cpus
122
123 /*
124 * They have to be macros in order to do the constant folding
125 * correctly - if the argument passed into a inline function
126 * it is no longer constant according to gcc..
127 */
128
129 #undef ntohl
130 #undef ntohs
131 #undef htonl
132 #undef htons
133
134 #define ___htonl(x) __cpu_to_be32(x)
135 #define ___htons(x) __cpu_to_be16(x)
136 #define ___ntohl(x) __be32_to_cpu(x)
137 #define ___ntohs(x) __be16_to_cpu(x)
138
139 #define htonl(x) ___htonl(x)
140 #define ntohl(x) ___ntohl(x)
141 #define htons(x) ___htons(x)
142 #define ntohs(x) ___ntohs(x)
143
144 static inline void le16_add_cpu(__le16 *var, u16 val)
145 {
146 *var = cpu_to_le16(le16_to_cpu(*var) + val);
147 }
148
149 static inline void le32_add_cpu(__le32 *var, u32 val)
150 {
151 *var = cpu_to_le32(le32_to_cpu(*var) + val);
152 }
153
154 static inline void le64_add_cpu(__le64 *var, u64 val)
155 {
156 *var = cpu_to_le64(le64_to_cpu(*var) + val);
157 }
158
159 /* XXX: this stuff can be optimized */
160 static inline void le32_to_cpu_array(u32 *buf, unsigned int words)
161 {
162 while (words--) {
163 __le32_to_cpus(buf);
164 buf++;
165 }
166 }
167
168 static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
169 {
170 while (words--) {
171 __cpu_to_le32s(buf);
172 buf++;
173 }
174 }
175
176 static inline void be16_add_cpu(__be16 *var, u16 val)
177 {
178 *var = cpu_to_be16(be16_to_cpu(*var) + val);
179 }
180
181 static inline void be32_add_cpu(__be32 *var, u32 val)
182 {
183 *var = cpu_to_be32(be32_to_cpu(*var) + val);
184 }
185
186 static inline void be64_add_cpu(__be64 *var, u64 val)
187 {
188 *var = cpu_to_be64(be64_to_cpu(*var) + val);
189 }
190
191 static inline void cpu_to_be32_array(__be32 *dst, const u32 *src, size_t len)
192 {
193 int i;
194
195 for (i = 0; i < len; i++)
196 dst[i] = cpu_to_be32(src[i]);
197 }
198
199 static inline void be32_to_cpu_array(u32 *dst, const __be32 *src, size_t len)
200 {
201 int i;
202
203 for (i = 0; i < len; i++)
204 dst[i] = be32_to_cpu(src[i]);
205 }
206
207 #endif /* _LINUX_BYTEORDER_GENERIC_H */