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 extern unsigned int __sw_hweight8(unsigned int w); 14 extern unsigned int __sw_hweight16(unsigned int w); 15 extern unsigned int __sw_hweight32(unsigned int w); 16 extern unsigned long __sw_hweight64(__u64 w); 17 18 /* 19 * Include this here because some architectures need generic_ffs/fls in 20 * scope 21 */ 22 #include <asm/bitops.h> 23 24 #define for_each_set_bit(bit, addr, size) \ 25 for ((bit) = find_first_bit((addr), (size)); \ 26 (bit) < (size); \ 27 (bit) = find_next_bit((addr), (size), (bit) + 1)) 28 29 /* same as for_each_set_bit() but use bit as value to start with */ 30 #define for_each_set_bit_cont(bit, addr, size) \ 31 for ((bit) = find_next_bit((addr), (size), (bit)); \ 32 (bit) < (size); \ 33 (bit) = find_next_bit((addr), (size), (bit) + 1)) 34 35 static __inline__ int get_bitmask_order(unsigned int count) 36 { 37 int order; 38 39 order = fls(count); 40 return order; /* We could be slightly more clever with -1 here... */ 41 } 42 43 static __inline__ int get_count_order(unsigned int count) 44 { 45 int order; 46 47 order = fls(count) - 1; 48 if (count & (count - 1)) 49 order++; 50 return order; 51 } 52 53 static inline unsigned long hweight_long(unsigned long w) 54 { 55 return sizeof(w) == 4 ? hweight32(w) : hweight64(w); 56 } 57 58 /** 59 * rol32 - rotate a 32-bit value left 60 * @word: value to rotate 61 * @shift: bits to roll 62 */ 63 static inline __u32 rol32(__u32 word, unsigned int shift) 64 { 65 return (word << shift) | (word >> (32 - shift)); 66 } 67 68 /** 69 * ror32 - rotate a 32-bit value right 70 * @word: value to rotate 71 * @shift: bits to roll 72 */ 73 static inline __u32 ror32(__u32 word, unsigned int shift) 74 { 75 return (word >> shift) | (word << (32 - shift)); 76 } 77 78 /** 79 * rol16 - rotate a 16-bit value left 80 * @word: value to rotate 81 * @shift: bits to roll 82 */ 83 static inline __u16 rol16(__u16 word, unsigned int shift) 84 { 85 return (word << shift) | (word >> (16 - shift)); 86 } 87 88 /** 89 * ror16 - rotate a 16-bit value right 90 * @word: value to rotate 91 * @shift: bits to roll 92 */ 93 static inline __u16 ror16(__u16 word, unsigned int shift) 94 { 95 return (word >> shift) | (word << (16 - shift)); 96 } 97 98 /** 99 * rol8 - rotate an 8-bit value left 100 * @word: value to rotate 101 * @shift: bits to roll 102 */ 103 static inline __u8 rol8(__u8 word, unsigned int shift) 104 { 105 return (word << shift) | (word >> (8 - shift)); 106 } 107 108 /** 109 * ror8 - rotate an 8-bit value right 110 * @word: value to rotate 111 * @shift: bits to roll 112 */ 113 static inline __u8 ror8(__u8 word, unsigned int shift) 114 { 115 return (word >> shift) | (word << (8 - shift)); 116 } 117 118 /** 119 * sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit 120 * @value: value to sign extend 121 * @index: 0 based bit index (0<=index<32) to sign bit 122 */ 123 static inline __s32 sign_extend32(__u32 value, int index) 124 { 125 __u8 shift = 31 - index; 126 return (__s32)(value << shift) >> shift; 127 } 128 129 static inline unsigned fls_long(unsigned long l) 130 { 131 if (sizeof(l) == 4) 132 return fls(l); 133 return fls64(l); 134 } 135 136 /** 137 * __ffs64 - find first set bit in a 64 bit word 138 * @word: The 64 bit word 139 * 140 * On 64 bit arches this is a synomyn for __ffs 141 * The result is not defined if no bits are set, so check that @word 142 * is non-zero before calling this. 143 */ 144 static inline unsigned long __ffs64(u64 word) 145 { 146 #if BITS_PER_LONG == 32 147 if (((u32)word) == 0UL) 148 return __ffs((u32)(word >> 32)) + 32; 149 #elif BITS_PER_LONG != 64 150 #error BITS_PER_LONG not 32 or 64 151 #endif 152 return __ffs((unsigned long)word); 153 } 154 155 #ifdef __KERNEL__ 156 157 #ifndef find_last_bit 158 /** 159 * find_last_bit - find the last set bit in a memory region 160 * @addr: The address to start the search at 161 * @size: The maximum size to search 162 * 163 * Returns the bit number of the first set bit, or size. 164 */ 165 extern unsigned long find_last_bit(const unsigned long *addr, 166 unsigned long size); 167 #endif 168 169 #endif /* __KERNEL__ */ 170 #endif 171