1 #ifndef _LINUX_BITOPS_H
2 #define _LINUX_BITOPS_H
6 #define BIT(nr) (1UL << (nr))
7 #define BIT_ULL(nr) (1ULL << (nr))
8 #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
9 #define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
10 #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
11 #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
12 #define BITS_PER_BYTE 8
13 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
16 extern unsigned int __sw_hweight8(unsigned int w);
17 extern unsigned int __sw_hweight16(unsigned int w);
18 extern unsigned int __sw_hweight32(unsigned int w);
19 extern unsigned long __sw_hweight64(__u64 w);
22 * Include this here because some architectures need generic_ffs/fls in
25 #include <asm/bitops.h>
27 #define for_each_set_bit(bit, addr, size) \
28 for ((bit) = find_first_bit((addr), (size)); \
30 (bit) = find_next_bit((addr), (size), (bit) + 1))
32 static __inline__ int get_bitmask_order(unsigned int count)
37 return order; /* We could be slightly more clever with -1 here... */
40 static __inline__ int get_count_order(unsigned int count)
44 order = fls(count) - 1;
45 if (count & (count - 1))
50 static inline unsigned long hweight_long(unsigned long w)
52 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
56 * rol64 - rotate a 64-bit value left
57 * @word: value to rotate
58 * @shift: bits to roll
60 static inline __u64 rol64(__u64 word, unsigned int shift)
62 return (word << shift) | (word >> (64 - shift));
66 * ror64 - rotate a 64-bit value right
67 * @word: value to rotate
68 * @shift: bits to roll
70 static inline __u64 ror64(__u64 word, unsigned int shift)
72 return (word >> shift) | (word << (64 - shift));
76 * rol32 - rotate a 32-bit value left
77 * @word: value to rotate
78 * @shift: bits to roll
80 static inline __u32 rol32(__u32 word, unsigned int shift)
82 return (word << shift) | (word >> (32 - shift));
86 * ror32 - rotate a 32-bit value right
87 * @word: value to rotate
88 * @shift: bits to roll
90 static inline __u32 ror32(__u32 word, unsigned int shift)
92 return (word >> shift) | (word << (32 - shift));
96 * rol16 - rotate a 16-bit value left
97 * @word: value to rotate
98 * @shift: bits to roll
100 static inline __u16 rol16(__u16 word, unsigned int shift)
102 return (word << shift) | (word >> (16 - shift));
106 * ror16 - rotate a 16-bit value right
107 * @word: value to rotate
108 * @shift: bits to roll
110 static inline __u16 ror16(__u16 word, unsigned int shift)
112 return (word >> shift) | (word << (16 - shift));
116 * rol8 - rotate an 8-bit value left
117 * @word: value to rotate
118 * @shift: bits to roll
120 static inline __u8 rol8(__u8 word, unsigned int shift)
122 return (word << shift) | (word >> (8 - shift));
126 * ror8 - rotate an 8-bit value right
127 * @word: value to rotate
128 * @shift: bits to roll
130 static inline __u8 ror8(__u8 word, unsigned int shift)
132 return (word >> shift) | (word << (8 - shift));
136 * sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit
137 * @value: value to sign extend
138 * @index: 0 based bit index (0<=index<32) to sign bit
140 static inline __s32 sign_extend32(__u32 value, int index)
142 __u8 shift = 31 - index;
143 return (__s32)(value << shift) >> shift;
146 static inline unsigned fls_long(unsigned long l)
154 * __ffs64 - find first set bit in a 64 bit word
155 * @word: The 64 bit word
157 * On 64 bit arches this is a synomyn for __ffs
158 * The result is not defined if no bits are set, so check that @word
159 * is non-zero before calling this.
161 static inline unsigned long __ffs64(u64 word)
163 #if BITS_PER_LONG == 32
164 if (((u32)word) == 0UL)
165 return __ffs((u32)(word >> 32)) + 32;
166 #elif BITS_PER_LONG != 64
167 #error BITS_PER_LONG not 32 or 64
169 return __ffs((unsigned long)word);
174 #ifndef set_mask_bits
175 #define set_mask_bits(ptr, _mask, _bits) \
177 const typeof(*ptr) mask = (_mask), bits = (_bits); \
178 typeof(*ptr) old, new; \
181 old = ACCESS_ONCE(*ptr); \
182 new = (old & ~mask) | bits; \
183 } while (cmpxchg(ptr, old, new) != old); \
189 #ifndef find_last_bit
191 * find_last_bit - find the last set bit in a memory region
192 * @addr: The address to start the search at
193 * @size: The maximum size to search
195 * Returns the bit number of the first set bit, or size.
197 extern unsigned long find_last_bit(const unsigned long *addr,
201 #endif /* __KERNEL__ */