1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _TOOLS_LINUX_FIND_H_ 3 #define _TOOLS_LINUX_FIND_H_ 4 5 #ifndef _TOOLS_LINUX_BITMAP_H 6 #error tools: only <linux/bitmap.h> can be included directly 7 #endif 8 9 #include <linux/bitops.h> 10 11 unsigned long _find_next_bit(const unsigned long *addr1, unsigned long nbits, 12 unsigned long start); 13 unsigned long _find_next_and_bit(const unsigned long *addr1, const unsigned long *addr2, 14 unsigned long nbits, unsigned long start); 15 unsigned long _find_next_zero_bit(const unsigned long *addr, unsigned long nbits, 16 unsigned long start); 17 extern unsigned long _find_first_bit(const unsigned long *addr, unsigned long size); 18 extern unsigned long _find_first_and_bit(const unsigned long *addr1, 19 const unsigned long *addr2, unsigned long size); 20 extern unsigned long _find_first_zero_bit(const unsigned long *addr, unsigned long size); 21 22 #ifndef find_next_bit 23 /** 24 * find_next_bit - find the next set bit in a memory region 25 * @addr: The address to base the search on 26 * @size: The bitmap size in bits 27 * @offset: The bitnumber to start searching at 28 * 29 * Returns the bit number for the next set bit 30 * If no bits are set, returns @size. 31 */ 32 static inline 33 unsigned long find_next_bit(const unsigned long *addr, unsigned long size, 34 unsigned long offset) 35 { 36 if (small_const_nbits(size)) { 37 unsigned long val; 38 39 if (unlikely(offset >= size)) 40 return size; 41 42 val = *addr & GENMASK(size - 1, offset); 43 return val ? __ffs(val) : size; 44 } 45 46 return _find_next_bit(addr, size, offset); 47 } 48 #endif 49 50 #ifndef find_next_and_bit 51 /** 52 * find_next_and_bit - find the next set bit in both memory regions 53 * @addr1: The first address to base the search on 54 * @addr2: The second address to base the search on 55 * @size: The bitmap size in bits 56 * @offset: The bitnumber to start searching at 57 * 58 * Returns the bit number for the next set bit 59 * If no bits are set, returns @size. 60 */ 61 static inline 62 unsigned long find_next_and_bit(const unsigned long *addr1, 63 const unsigned long *addr2, unsigned long size, 64 unsigned long offset) 65 { 66 if (small_const_nbits(size)) { 67 unsigned long val; 68 69 if (unlikely(offset >= size)) 70 return size; 71 72 val = *addr1 & *addr2 & GENMASK(size - 1, offset); 73 return val ? __ffs(val) : size; 74 } 75 76 return _find_next_and_bit(addr1, addr2, size, offset); 77 } 78 #endif 79 80 #ifndef find_next_zero_bit 81 /** 82 * find_next_zero_bit - find the next cleared bit in a memory region 83 * @addr: The address to base the search on 84 * @size: The bitmap size in bits 85 * @offset: The bitnumber to start searching at 86 * 87 * Returns the bit number of the next zero bit 88 * If no bits are zero, returns @size. 89 */ 90 static inline 91 unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, 92 unsigned long offset) 93 { 94 if (small_const_nbits(size)) { 95 unsigned long val; 96 97 if (unlikely(offset >= size)) 98 return size; 99 100 val = *addr | ~GENMASK(size - 1, offset); 101 return val == ~0UL ? size : ffz(val); 102 } 103 104 return _find_next_zero_bit(addr, size, offset); 105 } 106 #endif 107 108 #ifndef find_first_bit 109 /** 110 * find_first_bit - find the first set bit in a memory region 111 * @addr: The address to start the search at 112 * @size: The maximum number of bits to search 113 * 114 * Returns the bit number of the first set bit. 115 * If no bits are set, returns @size. 116 */ 117 static inline 118 unsigned long find_first_bit(const unsigned long *addr, unsigned long size) 119 { 120 if (small_const_nbits(size)) { 121 unsigned long val = *addr & GENMASK(size - 1, 0); 122 123 return val ? __ffs(val) : size; 124 } 125 126 return _find_first_bit(addr, size); 127 } 128 #endif 129 130 #ifndef find_first_and_bit 131 /** 132 * find_first_and_bit - find the first set bit in both memory regions 133 * @addr1: The first address to base the search on 134 * @addr2: The second address to base the search on 135 * @size: The bitmap size in bits 136 * 137 * Returns the bit number for the next set bit 138 * If no bits are set, returns @size. 139 */ 140 static inline 141 unsigned long find_first_and_bit(const unsigned long *addr1, 142 const unsigned long *addr2, 143 unsigned long size) 144 { 145 if (small_const_nbits(size)) { 146 unsigned long val = *addr1 & *addr2 & GENMASK(size - 1, 0); 147 148 return val ? __ffs(val) : size; 149 } 150 151 return _find_first_and_bit(addr1, addr2, size); 152 } 153 #endif 154 155 #ifndef find_first_zero_bit 156 /** 157 * find_first_zero_bit - find the first cleared bit in a memory region 158 * @addr: The address to start the search at 159 * @size: The maximum number of bits to search 160 * 161 * Returns the bit number of the first cleared bit. 162 * If no bits are zero, returns @size. 163 */ 164 static inline 165 unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size) 166 { 167 if (small_const_nbits(size)) { 168 unsigned long val = *addr | ~GENMASK(size - 1, 0); 169 170 return val == ~0UL ? size : ffz(val); 171 } 172 173 return _find_first_zero_bit(addr, size); 174 } 175 #endif 176 177 #endif /*__LINUX_FIND_H_ */ 178