1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _TOOLS_LINUX_ASM_GENERIC_BITOPS_FIND_H_
3 #define _TOOLS_LINUX_ASM_GENERIC_BITOPS_FIND_H_
4 
5 extern unsigned long _find_next_bit(const unsigned long *addr1,
6 		const unsigned long *addr2, unsigned long nbits,
7 		unsigned long start, unsigned long invert, unsigned long le);
8 extern unsigned long _find_first_bit(const unsigned long *addr, unsigned long size);
9 extern unsigned long _find_first_zero_bit(const unsigned long *addr, unsigned long size);
10 extern unsigned long _find_last_bit(const unsigned long *addr, unsigned long size);
11 
12 #ifndef find_next_bit
13 /**
14  * find_next_bit - find the next set bit in a memory region
15  * @addr: The address to base the search on
16  * @offset: The bitnumber to start searching at
17  * @size: The bitmap size in bits
18  *
19  * Returns the bit number for the next set bit
20  * If no bits are set, returns @size.
21  */
22 static inline
find_next_bit(const unsigned long * addr,unsigned long size,unsigned long offset)23 unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
24 			    unsigned long offset)
25 {
26 	if (small_const_nbits(size)) {
27 		unsigned long val;
28 
29 		if (unlikely(offset >= size))
30 			return size;
31 
32 		val = *addr & GENMASK(size - 1, offset);
33 		return val ? __ffs(val) : size;
34 	}
35 
36 	return _find_next_bit(addr, NULL, size, offset, 0UL, 0);
37 }
38 #endif
39 
40 #ifndef find_next_and_bit
41 /**
42  * find_next_and_bit - find the next set bit in both memory regions
43  * @addr1: The first address to base the search on
44  * @addr2: The second address to base the search on
45  * @offset: The bitnumber to start searching at
46  * @size: The bitmap size in bits
47  *
48  * Returns the bit number for the next set bit
49  * If no bits are set, returns @size.
50  */
51 static inline
find_next_and_bit(const unsigned long * addr1,const unsigned long * addr2,unsigned long size,unsigned long offset)52 unsigned long find_next_and_bit(const unsigned long *addr1,
53 		const unsigned long *addr2, unsigned long size,
54 		unsigned long offset)
55 {
56 	if (small_const_nbits(size)) {
57 		unsigned long val;
58 
59 		if (unlikely(offset >= size))
60 			return size;
61 
62 		val = *addr1 & *addr2 & GENMASK(size - 1, offset);
63 		return val ? __ffs(val) : size;
64 	}
65 
66 	return _find_next_bit(addr1, addr2, size, offset, 0UL, 0);
67 }
68 #endif
69 
70 #ifndef find_next_zero_bit
71 /**
72  * find_next_zero_bit - find the next cleared bit in a memory region
73  * @addr: The address to base the search on
74  * @offset: The bitnumber to start searching at
75  * @size: The bitmap size in bits
76  *
77  * Returns the bit number of the next zero bit
78  * If no bits are zero, returns @size.
79  */
80 static inline
find_next_zero_bit(const unsigned long * addr,unsigned long size,unsigned long offset)81 unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
82 				 unsigned long offset)
83 {
84 	if (small_const_nbits(size)) {
85 		unsigned long val;
86 
87 		if (unlikely(offset >= size))
88 			return size;
89 
90 		val = *addr | ~GENMASK(size - 1, offset);
91 		return val == ~0UL ? size : ffz(val);
92 	}
93 
94 	return _find_next_bit(addr, NULL, size, offset, ~0UL, 0);
95 }
96 #endif
97 
98 #ifndef find_first_bit
99 
100 /**
101  * find_first_bit - find the first set bit in a memory region
102  * @addr: The address to start the search at
103  * @size: The maximum number of bits to search
104  *
105  * Returns the bit number of the first set bit.
106  * If no bits are set, returns @size.
107  */
108 static inline
find_first_bit(const unsigned long * addr,unsigned long size)109 unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
110 {
111 	if (small_const_nbits(size)) {
112 		unsigned long val = *addr & GENMASK(size - 1, 0);
113 
114 		return val ? __ffs(val) : size;
115 	}
116 
117 	return _find_first_bit(addr, size);
118 }
119 
120 #endif /* find_first_bit */
121 
122 #ifndef find_first_zero_bit
123 
124 /**
125  * find_first_zero_bit - find the first cleared bit in a memory region
126  * @addr: The address to start the search at
127  * @size: The maximum number of bits to search
128  *
129  * Returns the bit number of the first cleared bit.
130  * If no bits are zero, returns @size.
131  */
132 static inline
find_first_zero_bit(const unsigned long * addr,unsigned long size)133 unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size)
134 {
135 	if (small_const_nbits(size)) {
136 		unsigned long val = *addr | ~GENMASK(size - 1, 0);
137 
138 		return val == ~0UL ? size : ffz(val);
139 	}
140 
141 	return _find_first_zero_bit(addr, size);
142 }
143 #endif
144 
145 #endif /*_TOOLS_LINUX_ASM_GENERIC_BITOPS_FIND_H_ */
146