1 #ifndef _LINUX_BITOPS_H
2 #define _LINUX_BITOPS_H
3
4 #if !defined(USE_HOSTCC) && !defined(__ASSEMBLY__)
5
6 #include <asm/types.h>
7 #include <asm-generic/bitsperlong.h>
8 #include <linux/compiler.h>
9
10 #ifdef __KERNEL__
11 #define BIT(nr) (1UL << (nr))
12 #define BIT_ULL(nr) (1ULL << (nr))
13 #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
14 #define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
15 #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
16 #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
17 #define BITS_PER_BYTE 8
18 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
19 #endif
20
21 /* kernel.h includes log.h which include bitops.h */
22 #include <linux/kernel.h>
23
24 /*
25 * Create a contiguous bitmask starting at bit position @l and ending at
26 * position @h. For example
27 * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
28 */
29 #ifdef CONFIG_SANDBOX
30 #define GENMASK(h, l) \
31 (((~0UL) << (l)) & (~0UL >> (CONFIG_SANDBOX_BITS_PER_LONG - 1 - (h))))
32 #else
33 #define GENMASK(h, l) \
34 (((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h))))
35 #endif
36
37 #define GENMASK_ULL(h, l) \
38 (((~0ULL) << (l)) & (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h))))
39
40 /*
41 * ffs: find first bit set. This is defined the same way as
42 * the libc and compiler builtin ffs routines, therefore
43 * differs in spirit from the above ffz (man ffs).
44 */
45
generic_ffs(int x)46 static inline int generic_ffs(int x)
47 {
48 int r = 1;
49
50 if (!x)
51 return 0;
52 if (!(x & 0xffff)) {
53 x >>= 16;
54 r += 16;
55 }
56 if (!(x & 0xff)) {
57 x >>= 8;
58 r += 8;
59 }
60 if (!(x & 0xf)) {
61 x >>= 4;
62 r += 4;
63 }
64 if (!(x & 3)) {
65 x >>= 2;
66 r += 2;
67 }
68 if (!(x & 1)) {
69 x >>= 1;
70 r += 1;
71 }
72 return r;
73 }
74
75 /**
76 * fls - find last (most-significant) bit set
77 * @x: the word to search
78 *
79 * This is defined the same way as ffs.
80 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
81 */
generic_fls(int x)82 static inline int generic_fls(int x)
83 {
84 int r = 32;
85
86 if (!x)
87 return 0;
88 if (!(x & 0xffff0000u)) {
89 x <<= 16;
90 r -= 16;
91 }
92 if (!(x & 0xff000000u)) {
93 x <<= 8;
94 r -= 8;
95 }
96 if (!(x & 0xf0000000u)) {
97 x <<= 4;
98 r -= 4;
99 }
100 if (!(x & 0xc0000000u)) {
101 x <<= 2;
102 r -= 2;
103 }
104 if (!(x & 0x80000000u)) {
105 x <<= 1;
106 r -= 1;
107 }
108 return r;
109 }
110
111
112 /*
113 * hweightN: returns the hamming weight (i.e. the number
114 * of bits set) of a N-bit word
115 */
116
generic_hweight32(unsigned int w)117 static inline unsigned int generic_hweight32(unsigned int w)
118 {
119 unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
120 res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
121 res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
122 res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
123 return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
124 }
125
generic_hweight16(unsigned int w)126 static inline unsigned int generic_hweight16(unsigned int w)
127 {
128 unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
129 res = (res & 0x3333) + ((res >> 2) & 0x3333);
130 res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
131 return (res & 0x00FF) + ((res >> 8) & 0x00FF);
132 }
133
generic_hweight8(unsigned int w)134 static inline unsigned int generic_hweight8(unsigned int w)
135 {
136 unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
137 res = (res & 0x33) + ((res >> 2) & 0x33);
138 return (res & 0x0F) + ((res >> 4) & 0x0F);
139 }
140
generic_hweight64(__u64 w)141 static inline unsigned long generic_hweight64(__u64 w)
142 {
143 return generic_hweight32((unsigned int)(w >> 32)) +
144 generic_hweight32((unsigned int)w);
145 }
146
hweight_long(unsigned long w)147 static inline unsigned long hweight_long(unsigned long w)
148 {
149 return sizeof(w) == 4 ? generic_hweight32(w) : generic_hweight64(w);
150 }
151
152 #include <asm/bitops.h>
153
154 /* linux/include/asm-generic/bitops/non-atomic.h */
155
156 #ifndef PLATFORM__SET_BIT
157 # define __set_bit generic_set_bit
158 #endif
159
160 #ifndef PLATFORM__CLEAR_BIT
161 # define __clear_bit generic_clear_bit
162 #endif
163
164 #ifndef PLATFORM_FFS
165 # define ffs generic_ffs
166 #endif
167
168 #ifndef PLATFORM_FLS
169 # define fls generic_fls
170 #endif
171
fls_long(unsigned long l)172 static inline unsigned fls_long(unsigned long l)
173 {
174 if (sizeof(l) == 4)
175 return fls(l);
176 return fls64(l);
177 }
178
179 /**
180 * __ffs64 - find first set bit in a 64 bit word
181 * @word: The 64 bit word
182 *
183 * On 64 bit arches this is a synomyn for __ffs
184 * The result is not defined if no bits are set, so check that @word
185 * is non-zero before calling this.
186 */
__ffs64(u64 word)187 static inline unsigned long __ffs64(u64 word)
188 {
189 #if BITS_PER_LONG == 32
190 if (((u32)word) == 0UL)
191 return __ffs((u32)(word >> 32)) + 32;
192 #elif BITS_PER_LONG != 64
193 #error BITS_PER_LONG not 32 or 64
194 #endif
195 return __ffs((unsigned long)word);
196 }
197
198 /**
199 * __set_bit - Set a bit in memory
200 * @nr: the bit to set
201 * @addr: the address to start counting from
202 *
203 * Unlike set_bit(), this function is non-atomic and may be reordered.
204 * If it's called on the same region of memory simultaneously, the effect
205 * may be that only one operation succeeds.
206 */
generic_set_bit(int nr,volatile unsigned long * addr)207 static inline void generic_set_bit(int nr, volatile unsigned long *addr)
208 {
209 unsigned long mask = BIT_MASK(nr);
210 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
211
212 *p |= mask;
213 }
214
generic_clear_bit(int nr,volatile unsigned long * addr)215 static inline void generic_clear_bit(int nr, volatile unsigned long *addr)
216 {
217 unsigned long mask = BIT_MASK(nr);
218 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
219
220 *p &= ~mask;
221 }
222
223 #endif /* !USE_HOSTCC && !__ASSEMBLY__ */
224
225 #endif
226