xref: /linux-6.15/include/linux/bitops.h (revision f035ac82)
1 #ifndef _LINUX_BITOPS_H
2 #define _LINUX_BITOPS_H
3 #include <asm/types.h>
4 
5 /*
6  * Include this here because some architectures need generic_ffs/fls in
7  * scope
8  */
9 #include <asm/bitops.h>
10 
11 #define for_each_bit(bit, addr, size) \
12 	for ((bit) = find_first_bit((addr), (size)); \
13 	     (bit) < (size); \
14 	     (bit) = find_next_bit((addr), (size), (bit) + 1))
15 
16 
17 static __inline__ int get_bitmask_order(unsigned int count)
18 {
19 	int order;
20 
21 	order = fls(count);
22 	return order;	/* We could be slightly more clever with -1 here... */
23 }
24 
25 static __inline__ int get_count_order(unsigned int count)
26 {
27 	int order;
28 
29 	order = fls(count) - 1;
30 	if (count & (count - 1))
31 		order++;
32 	return order;
33 }
34 
35 static inline unsigned long hweight_long(unsigned long w)
36 {
37 	return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
38 }
39 
40 /**
41  * rol32 - rotate a 32-bit value left
42  * @word: value to rotate
43  * @shift: bits to roll
44  */
45 static inline __u32 rol32(__u32 word, unsigned int shift)
46 {
47 	return (word << shift) | (word >> (32 - shift));
48 }
49 
50 /**
51  * ror32 - rotate a 32-bit value right
52  * @word: value to rotate
53  * @shift: bits to roll
54  */
55 static inline __u32 ror32(__u32 word, unsigned int shift)
56 {
57 	return (word >> shift) | (word << (32 - shift));
58 }
59 
60 static inline unsigned fls_long(unsigned long l)
61 {
62 	if (sizeof(l) == 4)
63 		return fls(l);
64 	return fls64(l);
65 }
66 
67 #endif
68