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 /* same as for_each_set_bit() but use bit as value to start with */
33 #define for_each_set_bit_from(bit, addr, size) \
34 for ((bit) = find_next_bit((addr), (size), (bit)); \
36 (bit) = find_next_bit((addr), (size), (bit) + 1))
38 #define for_each_clear_bit(bit, addr, size) \
39 for ((bit) = find_first_zero_bit((addr), (size)); \
41 (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
43 /* same as for_each_clear_bit() but use bit as value to start with */
44 #define for_each_clear_bit_from(bit, addr, size) \
45 for ((bit) = find_next_zero_bit((addr), (size), (bit)); \
47 (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
49 static __inline__ int get_bitmask_order(unsigned int count)
54 return order; /* We could be slightly more clever with -1 here... */
57 static __inline__ int get_count_order(unsigned int count)
61 order = fls(count) - 1;
62 if (count & (count - 1))
67 static inline unsigned long hweight_long(unsigned long w)
69 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
73 * rol64 - rotate a 64-bit value left
74 * @word: value to rotate
75 * @shift: bits to roll
77 static inline __u64 rol64(__u64 word, unsigned int shift)
79 return (word << shift) | (word >> (64 - shift));
83 * ror64 - rotate a 64-bit value right
84 * @word: value to rotate
85 * @shift: bits to roll
87 static inline __u64 ror64(__u64 word, unsigned int shift)
89 return (word >> shift) | (word << (64 - shift));
93 * rol32 - rotate a 32-bit value left
94 * @word: value to rotate
95 * @shift: bits to roll
97 static inline __u32 rol32(__u32 word, unsigned int shift)
99 return (word << shift) | (word >> (32 - shift));
103 * ror32 - rotate a 32-bit value right
104 * @word: value to rotate
105 * @shift: bits to roll
107 static inline __u32 ror32(__u32 word, unsigned int shift)
109 return (word >> shift) | (word << (32 - shift));
113 * rol16 - rotate a 16-bit value left
114 * @word: value to rotate
115 * @shift: bits to roll
117 static inline __u16 rol16(__u16 word, unsigned int shift)
119 return (word << shift) | (word >> (16 - shift));
123 * ror16 - rotate a 16-bit value right
124 * @word: value to rotate
125 * @shift: bits to roll
127 static inline __u16 ror16(__u16 word, unsigned int shift)
129 return (word >> shift) | (word << (16 - shift));
133 * rol8 - rotate an 8-bit value left
134 * @word: value to rotate
135 * @shift: bits to roll
137 static inline __u8 rol8(__u8 word, unsigned int shift)
139 return (word << shift) | (word >> (8 - shift));
143 * ror8 - rotate an 8-bit value right
144 * @word: value to rotate
145 * @shift: bits to roll
147 static inline __u8 ror8(__u8 word, unsigned int shift)
149 return (word >> shift) | (word << (8 - shift));
153 * sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit
154 * @value: value to sign extend
155 * @index: 0 based bit index (0<=index<32) to sign bit
157 static inline __s32 sign_extend32(__u32 value, int index)
159 __u8 shift = 31 - index;
160 return (__s32)(value << shift) >> shift;
163 static inline unsigned fls_long(unsigned long l)
171 * __ffs64 - find first set bit in a 64 bit word
172 * @word: The 64 bit word
174 * On 64 bit arches this is a synomyn for __ffs
175 * The result is not defined if no bits are set, so check that @word
176 * is non-zero before calling this.
178 static inline unsigned long __ffs64(u64 word)
180 #if BITS_PER_LONG == 32
181 if (((u32)word) == 0UL)
182 return __ffs((u32)(word >> 32)) + 32;
183 #elif BITS_PER_LONG != 64
184 #error BITS_PER_LONG not 32 or 64
186 return __ffs((unsigned long)word);
191 #ifndef find_last_bit
193 * find_last_bit - find the last set bit in a memory region
194 * @addr: The address to start the search at
195 * @size: The maximum size to search
197 * Returns the bit number of the first set bit, or size.
199 extern unsigned long find_last_bit(const unsigned long *addr,
203 #endif /* __KERNEL__ */