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