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_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))
14 #endif
15
16 /*
17 * Create a contiguous bitmask starting at bit position @l and ending at
18 * position @h. For example
19 * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
20 */
21 #define GENMASK(h, l) \
22 (((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h))))
23
24 #define GENMASK_ULL(h, l) \
25 (((~0ULL) << (l)) & (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h))))
26
27 extern unsigned int __sw_hweight8(unsigned int w);
28 extern unsigned int __sw_hweight16(unsigned int w);
29 extern unsigned int __sw_hweight32(unsigned int w);
30 extern unsigned long __sw_hweight64(__u64 w);
31
32 /*
33 * Include this here because some architectures need generic_ffs/fls in
34 * scope
35 */
36 #include <asm/bitops.h>
37
38 #define for_each_set_bit(bit, addr, size) \
39 for ((bit) = find_first_bit((addr), (size)); \
40 (bit) < (size); \
41 (bit) = find_next_bit((addr), (size), (bit) + 1))
42
43 /* same as for_each_set_bit() but use bit as value to start with */
44 #define for_each_set_bit_from(bit, addr, size) \
45 for ((bit) = find_next_bit((addr), (size), (bit)); \
46 (bit) < (size); \
47 (bit) = find_next_bit((addr), (size), (bit) + 1))
48
49 #define for_each_clear_bit(bit, addr, size) \
50 for ((bit) = find_first_zero_bit((addr), (size)); \
51 (bit) < (size); \
52 (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
53
54 /* same as for_each_clear_bit() but use bit as value to start with */
55 #define for_each_clear_bit_from(bit, addr, size) \
56 for ((bit) = find_next_zero_bit((addr), (size), (bit)); \
57 (bit) < (size); \
58 (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
59
get_bitmask_order(unsigned int count)60 static __inline__ int get_bitmask_order(unsigned int count)
61 {
62 int order;
63
64 order = fls(count);
65 return order; /* We could be slightly more clever with -1 here... */
66 }
67
get_count_order(unsigned int count)68 static __inline__ int get_count_order(unsigned int count)
69 {
70 int order;
71
72 order = fls(count) - 1;
73 if (count & (count - 1))
74 order++;
75 return order;
76 }
77
hweight_long(unsigned long w)78 static inline unsigned long hweight_long(unsigned long w)
79 {
80 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
81 }
82
83 /**
84 * rol64 - rotate a 64-bit value left
85 * @word: value to rotate
86 * @shift: bits to roll
87 */
rol64(__u64 word,unsigned int shift)88 static inline __u64 rol64(__u64 word, unsigned int shift)
89 {
90 return (word << shift) | (word >> (64 - shift));
91 }
92
93 /**
94 * ror64 - rotate a 64-bit value right
95 * @word: value to rotate
96 * @shift: bits to roll
97 */
ror64(__u64 word,unsigned int shift)98 static inline __u64 ror64(__u64 word, unsigned int shift)
99 {
100 return (word >> shift) | (word << (64 - shift));
101 }
102
103 /**
104 * rol32 - rotate a 32-bit value left
105 * @word: value to rotate
106 * @shift: bits to roll
107 */
rol32(__u32 word,unsigned int shift)108 static inline __u32 rol32(__u32 word, unsigned int shift)
109 {
110 return (word << shift) | (word >> (32 - shift));
111 }
112
113 /**
114 * ror32 - rotate a 32-bit value right
115 * @word: value to rotate
116 * @shift: bits to roll
117 */
ror32(__u32 word,unsigned int shift)118 static inline __u32 ror32(__u32 word, unsigned int shift)
119 {
120 return (word >> shift) | (word << (32 - shift));
121 }
122
123 /**
124 * rol16 - rotate a 16-bit value left
125 * @word: value to rotate
126 * @shift: bits to roll
127 */
rol16(__u16 word,unsigned int shift)128 static inline __u16 rol16(__u16 word, unsigned int shift)
129 {
130 return (word << shift) | (word >> (16 - shift));
131 }
132
133 /**
134 * ror16 - rotate a 16-bit value right
135 * @word: value to rotate
136 * @shift: bits to roll
137 */
ror16(__u16 word,unsigned int shift)138 static inline __u16 ror16(__u16 word, unsigned int shift)
139 {
140 return (word >> shift) | (word << (16 - shift));
141 }
142
143 /**
144 * rol8 - rotate an 8-bit value left
145 * @word: value to rotate
146 * @shift: bits to roll
147 */
rol8(__u8 word,unsigned int shift)148 static inline __u8 rol8(__u8 word, unsigned int shift)
149 {
150 return (word << shift) | (word >> (8 - shift));
151 }
152
153 /**
154 * ror8 - rotate an 8-bit value right
155 * @word: value to rotate
156 * @shift: bits to roll
157 */
ror8(__u8 word,unsigned int shift)158 static inline __u8 ror8(__u8 word, unsigned int shift)
159 {
160 return (word >> shift) | (word << (8 - shift));
161 }
162
163 /**
164 * sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit
165 * @value: value to sign extend
166 * @index: 0 based bit index (0<=index<32) to sign bit
167 */
sign_extend32(__u32 value,int index)168 static inline __s32 sign_extend32(__u32 value, int index)
169 {
170 __u8 shift = 31 - index;
171 return (__s32)(value << shift) >> shift;
172 }
173
174 /**
175 * sign_extend64 - sign extend a 64-bit value using specified bit as sign-bit
176 * @value: value to sign extend
177 * @index: 0 based bit index (0<=index<64) to sign bit
178 */
sign_extend64(__u64 value,int index)179 static inline __s64 sign_extend64(__u64 value, int index)
180 {
181 __u8 shift = 63 - index;
182 return (__s64)(value << shift) >> shift;
183 }
184
fls_long(unsigned long l)185 static inline unsigned fls_long(unsigned long l)
186 {
187 if (sizeof(l) == 4)
188 return fls(l);
189 return fls64(l);
190 }
191
192 /**
193 * __ffs64 - find first set bit in a 64 bit word
194 * @word: The 64 bit word
195 *
196 * On 64 bit arches this is a synomyn for __ffs
197 * The result is not defined if no bits are set, so check that @word
198 * is non-zero before calling this.
199 */
__ffs64(u64 word)200 static inline unsigned long __ffs64(u64 word)
201 {
202 #if BITS_PER_LONG == 32
203 if (((u32)word) == 0UL)
204 return __ffs((u32)(word >> 32)) + 32;
205 #elif BITS_PER_LONG != 64
206 #error BITS_PER_LONG not 32 or 64
207 #endif
208 return __ffs((unsigned long)word);
209 }
210
211 #ifdef __KERNEL__
212
213 #ifndef set_mask_bits
214 #define set_mask_bits(ptr, _mask, _bits) \
215 ({ \
216 const typeof(*ptr) mask = (_mask), bits = (_bits); \
217 typeof(*ptr) old, new; \
218 \
219 do { \
220 old = ACCESS_ONCE(*ptr); \
221 new = (old & ~mask) | bits; \
222 } while (cmpxchg(ptr, old, new) != old); \
223 \
224 new; \
225 })
226 #endif
227
228 #ifndef find_last_bit
229 /**
230 * find_last_bit - find the last set bit in a memory region
231 * @addr: The address to start the search at
232 * @size: The maximum size to search
233 *
234 * Returns the bit number of the first set bit, or size.
235 */
236 extern unsigned long find_last_bit(const unsigned long *addr,
237 unsigned long size);
238 #endif
239
240 #endif /* __KERNEL__ */
241 #endif
242