1 #ifndef _LINUX_BITOPS_H
2 #define _LINUX_BITOPS_H
3 #include <asm/types.h>
4
5 #ifdef __KERNEL__
6 #define BIT(nr) (1UL << (nr))
7 #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
8 #define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
9 #define BITS_PER_BYTE 8
10 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
11 #endif
12
13 /*
14 * Include this here because some architectures need generic_ffs/fls in
15 * scope
16 */
17 #include <asm/bitops.h>
18
19 #define for_each_bit(bit, addr, size) \
20 for ((bit) = find_first_bit((addr), (size)); \
21 (bit) < (size); \
22 (bit) = find_next_bit((addr), (size), (bit) + 1))
23
24
get_bitmask_order(unsigned int count)25 static __inline__ int get_bitmask_order(unsigned int count)
26 {
27 int order;
28
29 order = fls(count);
30 return order; /* We could be slightly more clever with -1 here... */
31 }
32
get_count_order(unsigned int count)33 static __inline__ int get_count_order(unsigned int count)
34 {
35 int order;
36
37 order = fls(count) - 1;
38 if (count & (count - 1))
39 order++;
40 return order;
41 }
42
hweight_long(unsigned long w)43 static inline unsigned long hweight_long(unsigned long w)
44 {
45 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
46 }
47
48 /**
49 * rol32 - rotate a 32-bit value left
50 * @word: value to rotate
51 * @shift: bits to roll
52 */
rol32(__u32 word,unsigned int shift)53 static inline __u32 rol32(__u32 word, unsigned int shift)
54 {
55 return (word << shift) | (word >> (32 - shift));
56 }
57
58 /**
59 * ror32 - rotate a 32-bit value right
60 * @word: value to rotate
61 * @shift: bits to roll
62 */
ror32(__u32 word,unsigned int shift)63 static inline __u32 ror32(__u32 word, unsigned int shift)
64 {
65 return (word >> shift) | (word << (32 - shift));
66 }
67
68 /**
69 * rol16 - rotate a 16-bit value left
70 * @word: value to rotate
71 * @shift: bits to roll
72 */
rol16(__u16 word,unsigned int shift)73 static inline __u16 rol16(__u16 word, unsigned int shift)
74 {
75 return (word << shift) | (word >> (16 - shift));
76 }
77
78 /**
79 * ror16 - rotate a 16-bit value right
80 * @word: value to rotate
81 * @shift: bits to roll
82 */
ror16(__u16 word,unsigned int shift)83 static inline __u16 ror16(__u16 word, unsigned int shift)
84 {
85 return (word >> shift) | (word << (16 - shift));
86 }
87
88 /**
89 * rol8 - rotate an 8-bit value left
90 * @word: value to rotate
91 * @shift: bits to roll
92 */
rol8(__u8 word,unsigned int shift)93 static inline __u8 rol8(__u8 word, unsigned int shift)
94 {
95 return (word << shift) | (word >> (8 - shift));
96 }
97
98 /**
99 * ror8 - rotate an 8-bit value right
100 * @word: value to rotate
101 * @shift: bits to roll
102 */
ror8(__u8 word,unsigned int shift)103 static inline __u8 ror8(__u8 word, unsigned int shift)
104 {
105 return (word >> shift) | (word << (8 - shift));
106 }
107
fls_long(unsigned long l)108 static inline unsigned fls_long(unsigned long l)
109 {
110 if (sizeof(l) == 4)
111 return fls(l);
112 return fls64(l);
113 }
114
115 #ifdef __KERNEL__
116 #ifdef CONFIG_GENERIC_FIND_FIRST_BIT
117
118 /**
119 * find_first_bit - find the first set bit in a memory region
120 * @addr: The address to start the search at
121 * @size: The maximum size to search
122 *
123 * Returns the bit number of the first set bit.
124 */
125 extern unsigned long find_first_bit(const unsigned long *addr,
126 unsigned long size);
127
128 /**
129 * find_first_zero_bit - find the first cleared bit in a memory region
130 * @addr: The address to start the search at
131 * @size: The maximum size to search
132 *
133 * Returns the bit number of the first cleared bit.
134 */
135 extern unsigned long find_first_zero_bit(const unsigned long *addr,
136 unsigned long size);
137 #endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
138
139 #ifdef CONFIG_GENERIC_FIND_LAST_BIT
140 /**
141 * find_last_bit - find the last set bit in a memory region
142 * @addr: The address to start the search at
143 * @size: The maximum size to search
144 *
145 * Returns the bit number of the first set bit, or size.
146 */
147 extern unsigned long find_last_bit(const unsigned long *addr,
148 unsigned long size);
149 #endif /* CONFIG_GENERIC_FIND_LAST_BIT */
150
151 #ifdef CONFIG_GENERIC_FIND_NEXT_BIT
152
153 /**
154 * find_next_bit - find the next set bit in a memory region
155 * @addr: The address to base the search on
156 * @offset: The bitnumber to start searching at
157 * @size: The bitmap size in bits
158 */
159 extern unsigned long find_next_bit(const unsigned long *addr,
160 unsigned long size, unsigned long offset);
161
162 /**
163 * find_next_zero_bit - find the next cleared bit in a memory region
164 * @addr: The address to base the search on
165 * @offset: The bitnumber to start searching at
166 * @size: The bitmap size in bits
167 */
168
169 extern unsigned long find_next_zero_bit(const unsigned long *addr,
170 unsigned long size,
171 unsigned long offset);
172
173 #endif /* CONFIG_GENERIC_FIND_NEXT_BIT */
174 #endif /* __KERNEL__ */
175 #endif
176