1 /* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0-only */ 2 3 #ifndef COMMONLIB_BSD_HELPERS_H 4 #define COMMONLIB_BSD_HELPERS_H 5 6 #ifndef __ASSEMBLER__ 7 #include <commonlib/bsd/compiler.h> 8 #include <stddef.h> 9 #endif 10 11 #ifndef ARRAY_SIZE 12 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0])) 13 #endif 14 15 #define ALIGN(x, a) __ALIGN_MASK(x, (__typeof__(x))(a)-1UL) 16 #define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask)) 17 #define ALIGN_UP(x, a) ALIGN((x), (a)) 18 #define ALIGN_DOWN(x, a) ((x) & ~((__typeof__(x))(a)-1UL)) 19 #define IS_ALIGNED(x, a) (((x) & ((__typeof__(x))(a)-1UL)) == 0) 20 21 /* Double-evaluation unsafe min/max, for bitfields and outside of functions */ 22 #define __CMP_UNSAFE(a, b, op) ((a) op (b) ? (a) : (b)) 23 #define MIN_UNSAFE(a, b) __CMP_UNSAFE(a, b, <) 24 #define MAX_UNSAFE(a, b) __CMP_UNSAFE(a, b, >) 25 26 #define __CMP_SAFE(a, b, op, var_a, var_b) ({ \ 27 __TYPEOF_UNLESS_CONST(a, b) var_a = (a); \ 28 __TYPEOF_UNLESS_CONST(b, a) var_b = (b); \ 29 var_a op var_b ? var_a : var_b; \ 30 }) 31 32 #define __CMP(a, b, op) __builtin_choose_expr( \ 33 __builtin_constant_p(a) && __builtin_constant_p(b), \ 34 __CMP_UNSAFE(a, b, op), __CMP_SAFE(a, b, op, __TMPNAME, __TMPNAME)) 35 36 #ifndef MIN 37 #define MIN(a, b) __CMP(a, b, <) 38 #endif 39 #ifndef MAX 40 #define MAX(a, b) __CMP(a, b, >) 41 #endif 42 43 #ifndef ABS 44 #define ABS(a) ({ \ 45 __typeof__(a) _abs_local_a = (a); \ 46 (_abs_local_a < 0) ? (-_abs_local_a) : _abs_local_a; \ 47 }) 48 #endif 49 50 #define IS_POWER_OF_2(x) ({ \ 51 __typeof__(x) _power_local_x = (x); \ 52 (_power_local_x & (_power_local_x - 1)) == 0; \ 53 }) 54 55 #define POWER_OF_2(x) (1ULL << (x)) 56 57 /* Set bits from `high` to `low` (inclusive). */ 58 #define GENMASK(high, low) (((~0ULL) << (low)) & (~0ULL >> (63 - (high)))) 59 60 #define DIV_ROUND_UP(x, y) ({ \ 61 __typeof__(x) _div_local_x = (x); \ 62 __typeof__(y) _div_local_y = (y); \ 63 (_div_local_x + _div_local_y - 1) / _div_local_y; \ 64 }) 65 66 #define SWAP(a, b) do { \ 67 __typeof__(&(a)) _swap_local_a = &(a); \ 68 __typeof__(&(b)) _swap_local_b = &(b); \ 69 __typeof__(a) _swap_local_tmp = *_swap_local_a; \ 70 *_swap_local_a = *_swap_local_b; \ 71 *_swap_local_b = _swap_local_tmp; \ 72 } while (0) 73 74 /* Standard units. */ 75 #define KiB (1<<10) 76 #define MiB (1<<20) 77 #define GiB (1<<30) 78 79 #define KHz (1000) 80 #define MHz (1000 * KHz) 81 #define GHz (1000 * MHz) 82 83 #ifndef offsetof 84 #define offsetof(TYPE, MEMBER) __builtin_offsetof(TYPE, MEMBER) 85 #endif 86 87 #define check_member(structure, member, offset) _Static_assert( \ 88 offsetof(struct structure, member) == offset, \ 89 "`struct " #structure "` offset for `" #member "` is not " #offset) 90 91 /* Calculate size of structure member. */ 92 #define member_size(type, member) (sizeof(((type *)0)->member)) 93 94 #define _retry_impl(attempts, condition, expr, ...) \ 95 ({ \ 96 __typeof__(condition) _retry_ret = \ 97 (__typeof__(condition))0; \ 98 int _retry_attempts = (attempts); \ 99 do { \ 100 _retry_ret = (condition); \ 101 if (_retry_ret) \ 102 break; \ 103 if (--_retry_attempts > 0) { \ 104 expr; \ 105 } else { \ 106 break; \ 107 } \ 108 } while (1); \ 109 _retry_ret; \ 110 }) 111 112 /* 113 * Helper macro to retry until a condition becomes true or the maximum number 114 * of attempts is reached. Two forms are supported: 115 * 116 * 1. retry(attempts, condition) 117 * 2. retry(attempts, condition, expr) 118 * 119 * @param attempts Maximum attempts. 120 * @param condition Condition to retry for. 121 * @param expr Procedure to run between each evaluation to "condition". 122 * 123 * @return Condition value if it evaluates to true within the maximum attempts; 124 * 0 otherwise. 125 */ 126 #define retry(attempts, condition, ...) \ 127 _retry_impl(attempts, condition, __VA_ARGS__) 128 129 /* Stringify a token */ 130 #ifndef STRINGIFY 131 #define _STRINGIFY(x) #x 132 #define STRINGIFY(x) _STRINGIFY(x) 133 #endif 134 135 #endif /* COMMONLIB_BSD_HELPERS_H */ 136