1 #ifndef _BITOPS_H_ 2 #define _BITOPS_H_ 3 4 /* 5 * Adapted from 6 * include/linux/bitops.h 7 * 8 * Copyright (C) 2017, Red Hat Inc, Andrew Jones <drjones@redhat.com> 9 * 10 * This work is licensed under the terms of the GNU GPL, version 2. 11 */ 12 13 #define BITS_PER_LONG_LONG 64 14 #define BIT(nr) (1UL << (nr)) 15 #define BIT_ULL(nr) (1ULL << (nr)) 16 #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) 17 #define BIT_WORD(nr) ((nr) / BITS_PER_LONG) 18 #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG)) 19 #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG) 20 #define BITS_PER_BYTE 8 21 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) 22 23 #include <asm/bitops.h> 24 25 /* 26 * Create a contiguous bitmask starting at bit position @l and ending at 27 * position @h. For example 28 * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000. 29 */ 30 #define GENMASK(h, l) \ 31 (((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h)))) 32 33 #define GENMASK_ULL(h, l) \ 34 (((~0ULL) << (l)) & (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h)))) 35 36 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) 37 #define lower_32_bits(n) ((u32)(n)) 38 39 #ifndef HAVE_BUILTIN_FLS 40 static inline unsigned long fls(unsigned long word) 41 { 42 int num = BITS_PER_LONG - 1; 43 44 #if BITS_PER_LONG == 64 45 if (!(word & (~0ul << 32))) { 46 num -= 32; 47 word <<= 32; 48 } 49 #endif 50 if (!(word & (~0ul << (BITS_PER_LONG-16)))) { 51 num -= 16; 52 word <<= 16; 53 } 54 if (!(word & (~0ul << (BITS_PER_LONG-8)))) { 55 num -= 8; 56 word <<= 8; 57 } 58 if (!(word & (~0ul << (BITS_PER_LONG-4)))) { 59 num -= 4; 60 word <<= 4; 61 } 62 if (!(word & (~0ul << (BITS_PER_LONG-2)))) { 63 num -= 2; 64 word <<= 2; 65 } 66 if (!(word & (~0ul << (BITS_PER_LONG-1)))) 67 num -= 1; 68 return num; 69 } 70 #else 71 static inline unsigned long fls(unsigned long word) 72 { 73 return BITS_PER_LONG - __builtin_clzl(word) - 1; 74 } 75 #endif 76 77 static inline bool is_power_of_2(unsigned long n) 78 { 79 return n && !(n & (n - 1)); 80 } 81 82 static inline unsigned int get_order(size_t size) 83 { 84 return size ? fls(size) + !is_power_of_2(size) : 0; 85 } 86 87 #endif 88