1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2020-2024 The FreeBSD Foundation 5 * 6 * This software was developed by Björn Zeeb under sponsorship from 7 * the FreeBSD Foundation. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #ifndef _LINUXKPI_LINUX_BITFIELD_H 32 #define _LINUXKPI_LINUX_BITFIELD_H 33 34 #include <linux/types.h> 35 #include <asm/byteorder.h> 36 37 /* Use largest possible type. */ 38 static inline uint64_t ___lsb(uint64_t f) { return (f & -f); } 39 static inline uint64_t ___bitmask(uint64_t f) { return (f / ___lsb(f)); } 40 41 #define _uX_get_bits(_n) \ 42 static __inline uint ## _n ## _t \ 43 u ## _n ## _get_bits(uint ## _n ## _t v, uint ## _n ## _t f) \ 44 { \ 45 return ((v & f) / ___lsb(f)); \ 46 } 47 48 _uX_get_bits(64) 49 _uX_get_bits(32) 50 _uX_get_bits(16) 51 _uX_get_bits(8) 52 53 #define _leX_get_bits(_n) \ 54 static __inline uint ## _n ## _t \ 55 le ## _n ## _get_bits(__le ## _n v, uint ## _n ## _t f) \ 56 { \ 57 return ((le ## _n ## _to_cpu(v) & f) / ___lsb(f)); \ 58 } 59 60 _leX_get_bits(64) 61 _leX_get_bits(32) 62 _leX_get_bits(16) 63 64 #define _uX_encode_bits(_n) \ 65 static __inline uint ## _n ## _t \ 66 u ## _n ## _encode_bits(uint ## _n ## _t v, uint ## _n ## _t f) \ 67 { \ 68 return ((v & ___bitmask(f)) * ___lsb(f)); \ 69 } 70 71 _uX_encode_bits(64) 72 _uX_encode_bits(32) 73 _uX_encode_bits(16) 74 _uX_encode_bits(8) 75 76 #define _leX_encode_bits(_n) \ 77 static __inline uint ## _n ## _t \ 78 le ## _n ## _encode_bits(__le ## _n v, uint ## _n ## _t f) \ 79 { \ 80 return (cpu_to_le ## _n((v & ___bitmask(f)) * ___lsb(f))); \ 81 } 82 83 _leX_encode_bits(64) 84 _leX_encode_bits(32) 85 _leX_encode_bits(16) 86 87 #define _leXp_replace_bits(_n) \ 88 static __inline void \ 89 le ## _n ## p_replace_bits(uint ## _n ## _t *p, \ 90 uint ## _n ## _t v, uint ## _n ## _t f) \ 91 { \ 92 *p = (*p & ~(cpu_to_le ## _n(f))) | \ 93 le ## _n ## _encode_bits(v, f); \ 94 } 95 96 _leXp_replace_bits(64) 97 _leXp_replace_bits(32) 98 _leXp_replace_bits(16) 99 100 #define _uXp_replace_bits(_n) \ 101 static __inline void \ 102 u ## _n ## p_replace_bits(uint ## _n ## _t *p, \ 103 uint ## _n ## _t v, uint ## _n ## _t f) \ 104 { \ 105 *p = (*p & ~f) | u ## _n ## _encode_bits(v, f); \ 106 } 107 108 _uXp_replace_bits(64) 109 _uXp_replace_bits(32) 110 _uXp_replace_bits(16) 111 _uXp_replace_bits(8) 112 113 #define _uX_replace_bits(_n) \ 114 static __inline uint ## _n ## _t \ 115 u ## _n ## _replace_bits(uint ## _n ## _t p, \ 116 uint ## _n ## _t v, uint ## _n ## _t f) \ 117 { \ 118 return ((p & ~f) | u ## _n ## _encode_bits(v, f)); \ 119 } 120 121 _uX_replace_bits(64) 122 _uX_replace_bits(32) 123 _uX_replace_bits(16) 124 _uX_replace_bits(8) 125 126 #define __bf_shf(x) (__builtin_ffsll(x) - 1) 127 128 #define FIELD_FIT(_mask, _value) \ 129 (!(((typeof(_mask))(_value) << __bf_shf(_mask)) & ~(_mask))) 130 131 #define FIELD_PREP(_mask, _value) \ 132 (((typeof(_mask))(_value) << __bf_shf(_mask)) & (_mask)) 133 134 /* Likely would need extra sanity checks compared to FIELD_PREP()? */ 135 #define FIELD_PREP_CONST(_mask, _value) \ 136 (((typeof(_mask))(_value) << __bf_shf(_mask)) & (_mask)) 137 138 #define FIELD_GET(_mask, _value) \ 139 ((typeof(_mask))(((_value) & (_mask)) >> __bf_shf(_mask))) 140 141 #endif /* _LINUXKPI_LINUX_BITFIELD_H */ 142