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