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_set_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 static __inline__ int get_bitmask_order(unsigned int count) 25 { 26 int order; 27 28 order = fls(count); 29 return order; /* We could be slightly more clever with -1 here... */ 30 } 31 32 static __inline__ int get_count_order(unsigned int count) 33 { 34 int order; 35 36 order = fls(count) - 1; 37 if (count & (count - 1)) 38 order++; 39 return order; 40 } 41 42 static inline unsigned long hweight_long(unsigned long w) 43 { 44 return sizeof(w) == 4 ? hweight32(w) : hweight64(w); 45 } 46 47 /* 48 * Clearly slow versions of the hweightN() functions, their benefit is 49 * of course compile time evaluation of constant arguments. 50 */ 51 #define HWEIGHT8(w) \ 52 ( BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + \ 53 (!!((w) & (1ULL << 0))) + \ 54 (!!((w) & (1ULL << 1))) + \ 55 (!!((w) & (1ULL << 2))) + \ 56 (!!((w) & (1ULL << 3))) + \ 57 (!!((w) & (1ULL << 4))) + \ 58 (!!((w) & (1ULL << 5))) + \ 59 (!!((w) & (1ULL << 6))) + \ 60 (!!((w) & (1ULL << 7))) ) 61 62 #define HWEIGHT16(w) (HWEIGHT8(w) + HWEIGHT8((w) >> 8)) 63 #define HWEIGHT32(w) (HWEIGHT16(w) + HWEIGHT16((w) >> 16)) 64 #define HWEIGHT64(w) (HWEIGHT32(w) + HWEIGHT32((w) >> 32)) 65 66 /* 67 * Type invariant version that simply casts things to the 68 * largest type. 69 */ 70 #define HWEIGHT(w) HWEIGHT64((u64)(w)) 71 72 /** 73 * rol32 - rotate a 32-bit value left 74 * @word: value to rotate 75 * @shift: bits to roll 76 */ 77 static inline __u32 rol32(__u32 word, unsigned int shift) 78 { 79 return (word << shift) | (word >> (32 - shift)); 80 } 81 82 /** 83 * ror32 - rotate a 32-bit value right 84 * @word: value to rotate 85 * @shift: bits to roll 86 */ 87 static inline __u32 ror32(__u32 word, unsigned int shift) 88 { 89 return (word >> shift) | (word << (32 - shift)); 90 } 91 92 /** 93 * rol16 - rotate a 16-bit value left 94 * @word: value to rotate 95 * @shift: bits to roll 96 */ 97 static inline __u16 rol16(__u16 word, unsigned int shift) 98 { 99 return (word << shift) | (word >> (16 - shift)); 100 } 101 102 /** 103 * ror16 - rotate a 16-bit value right 104 * @word: value to rotate 105 * @shift: bits to roll 106 */ 107 static inline __u16 ror16(__u16 word, unsigned int shift) 108 { 109 return (word >> shift) | (word << (16 - shift)); 110 } 111 112 /** 113 * rol8 - rotate an 8-bit value left 114 * @word: value to rotate 115 * @shift: bits to roll 116 */ 117 static inline __u8 rol8(__u8 word, unsigned int shift) 118 { 119 return (word << shift) | (word >> (8 - shift)); 120 } 121 122 /** 123 * ror8 - rotate an 8-bit value right 124 * @word: value to rotate 125 * @shift: bits to roll 126 */ 127 static inline __u8 ror8(__u8 word, unsigned int shift) 128 { 129 return (word >> shift) | (word << (8 - shift)); 130 } 131 132 static inline unsigned fls_long(unsigned long l) 133 { 134 if (sizeof(l) == 4) 135 return fls(l); 136 return fls64(l); 137 } 138 139 /** 140 * __ffs64 - find first set bit in a 64 bit word 141 * @word: The 64 bit word 142 * 143 * On 64 bit arches this is a synomyn for __ffs 144 * The result is not defined if no bits are set, so check that @word 145 * is non-zero before calling this. 146 */ 147 static inline unsigned long __ffs64(u64 word) 148 { 149 #if BITS_PER_LONG == 32 150 if (((u32)word) == 0UL) 151 return __ffs((u32)(word >> 32)) + 32; 152 #elif BITS_PER_LONG != 64 153 #error BITS_PER_LONG not 32 or 64 154 #endif 155 return __ffs((unsigned long)word); 156 } 157 158 #ifdef __KERNEL__ 159 #ifdef CONFIG_GENERIC_FIND_FIRST_BIT 160 161 /** 162 * find_first_bit - find the first set bit in a memory region 163 * @addr: The address to start the search at 164 * @size: The maximum size to search 165 * 166 * Returns the bit number of the first set bit. 167 */ 168 extern unsigned long find_first_bit(const unsigned long *addr, 169 unsigned long size); 170 171 /** 172 * find_first_zero_bit - find the first cleared bit in a memory region 173 * @addr: The address to start the search at 174 * @size: The maximum size to search 175 * 176 * Returns the bit number of the first cleared bit. 177 */ 178 extern unsigned long find_first_zero_bit(const unsigned long *addr, 179 unsigned long size); 180 #endif /* CONFIG_GENERIC_FIND_FIRST_BIT */ 181 182 #ifdef CONFIG_GENERIC_FIND_LAST_BIT 183 /** 184 * find_last_bit - find the last set bit in a memory region 185 * @addr: The address to start the search at 186 * @size: The maximum size to search 187 * 188 * Returns the bit number of the first set bit, or size. 189 */ 190 extern unsigned long find_last_bit(const unsigned long *addr, 191 unsigned long size); 192 #endif /* CONFIG_GENERIC_FIND_LAST_BIT */ 193 194 #ifdef CONFIG_GENERIC_FIND_NEXT_BIT 195 196 /** 197 * find_next_bit - find the next set bit in a memory region 198 * @addr: The address to base the search on 199 * @offset: The bitnumber to start searching at 200 * @size: The bitmap size in bits 201 */ 202 extern unsigned long find_next_bit(const unsigned long *addr, 203 unsigned long size, unsigned long offset); 204 205 /** 206 * find_next_zero_bit - find the next cleared bit in a memory region 207 * @addr: The address to base the search on 208 * @offset: The bitnumber to start searching at 209 * @size: The bitmap size in bits 210 */ 211 212 extern unsigned long find_next_zero_bit(const unsigned long *addr, 213 unsigned long size, 214 unsigned long offset); 215 216 #endif /* CONFIG_GENERIC_FIND_NEXT_BIT */ 217 #endif /* __KERNEL__ */ 218 #endif 219