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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
46static 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 */
82static 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 * hweightN: returns the hamming weight (i.e. the number
113 * of bits set) of a N-bit word
114 */
115
116static inline unsigned int generic_hweight32(unsigned int w)
117{
118 unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
119 res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
120 res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
121 res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
122 return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
123}
124
125static inline unsigned int generic_hweight16(unsigned int w)
126{
127 unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
128 res = (res & 0x3333) + ((res >> 2) & 0x3333);
129 res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
130 return (res & 0x00FF) + ((res >> 8) & 0x00FF);
131}
132
133static inline unsigned int generic_hweight8(unsigned int w)
134{
135 unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
136 res = (res & 0x33) + ((res >> 2) & 0x33);
137 return (res & 0x0F) + ((res >> 4) & 0x0F);
138}
139
140static inline unsigned long generic_hweight64(__u64 w)
141{
142 return generic_hweight32((unsigned int)(w >> 32)) +
143 generic_hweight32((unsigned int)w);
144}
145
146static inline unsigned long hweight_long(unsigned long w)
147{
148 return sizeof(w) == 4 ? generic_hweight32(w) : generic_hweight64(w);
149}
150
151#include <asm/bitops.h>
152
153/* linux/include/asm-generic/bitops/non-atomic.h */
154
155#ifndef PLATFORM__SET_BIT
156# define __set_bit generic_set_bit
157#endif
158
159#ifndef PLATFORM__CLEAR_BIT
160# define __clear_bit generic_clear_bit
161#endif
162
163#ifndef PLATFORM_FFS
164# define ffs generic_ffs
165#endif
166
167#ifndef PLATFORM_FLS
168# define fls generic_fls
169#endif
170
171static inline unsigned fls_long(unsigned long l)
172{
173 if (sizeof(l) == 4)
174 return fls(l);
175 return fls64(l);
176}
177
178/**
179 * __ffs64 - find first set bit in a 64 bit word
180 * @word: The 64 bit word
181 *
182 * On 64 bit arches this is a synomyn for __ffs
183 * The result is not defined if no bits are set, so check that @word
184 * is non-zero before calling this.
185 */
186static inline unsigned long __ffs64(u64 word)
187{
188#if BITS_PER_LONG == 32
189 if (((u32)word) == 0UL)
190 return __ffs((u32)(word >> 32)) + 32;
191#elif BITS_PER_LONG != 64
192#error BITS_PER_LONG not 32 or 64
193#endif
194 return __ffs((unsigned long)word);
195}
196
197/**
198 * __set_bit - Set a bit in memory
199 * @nr: the bit to set
200 * @addr: the address to start counting from
201 *
202 * Unlike set_bit(), this function is non-atomic and may be reordered.
203 * If it's called on the same region of memory simultaneously, the effect
204 * may be that only one operation succeeds.
205 */
206static inline void generic_set_bit(int nr, volatile unsigned long *addr)
207{
208 unsigned long mask = BIT_MASK(nr);
209 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
210
211 *p |= mask;
212}
213
214static inline void generic_clear_bit(int nr, volatile unsigned long *addr)
215{
216 unsigned long mask = BIT_MASK(nr);
217 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
218
219 *p &= ~mask;
220}
221
222#endif /* !USE_HOSTCC && !__ASSEMBLY__ */
223
224#endif