1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0 3 * 4 * Copyright (c) 2004 Topspin Corporation. All rights reserved. 5 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved. 6 * 7 * This software is available to you under a choice of one of two 8 * licenses. You may choose to be licensed under the terms of the GNU 9 * General Public License (GPL) Version 2, available from the file 10 * COPYING in the main directory of this source tree, or the 11 * OpenIB.org BSD license below: 12 * 13 * Redistribution and use in source and binary forms, with or 14 * without modification, are permitted provided that the following 15 * conditions are met: 16 * 17 * - Redistributions of source code must retain the above 18 * copyright notice, this list of conditions and the following 19 * disclaimer. 20 * 21 * - Redistributions in binary form must reproduce the above 22 * copyright notice, this list of conditions and the following 23 * disclaimer in the documentation and/or other materials 24 * provided with the distribution. 25 * 26 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 27 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 28 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 29 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 30 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 31 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 32 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 33 * SOFTWARE. 34 * 35 * $FreeBSD$ 36 */ 37 38 #include <linux/string.h> 39 40 #include <rdma/ib_pack.h> 41 42 static u64 value_read(int offset, int size, void *structure) 43 { 44 switch (size) { 45 case 1: return *(u8 *) ((char *)structure + offset); 46 case 2: return be16_to_cpup((__be16 *) ((char *)structure + offset)); 47 case 4: return be32_to_cpup((__be32 *) ((char *)structure + offset)); 48 case 8: return be64_to_cpup((__be64 *) ((char *)structure + offset)); 49 default: 50 pr_warn("Field size %d bits not handled\n", size * 8); 51 return 0; 52 } 53 } 54 55 /** 56 * ib_pack - Pack a structure into a buffer 57 * @desc:Array of structure field descriptions 58 * @desc_len:Number of entries in @desc 59 * @structure:Structure to pack from 60 * @buf:Buffer to pack into 61 * 62 * ib_pack() packs a list of structure fields into a buffer, 63 * controlled by the array of fields in @desc. 64 */ 65 void ib_pack(const struct ib_field *desc, 66 int desc_len, 67 void *structure, 68 void *buf) 69 { 70 int i; 71 72 for (i = 0; i < desc_len; ++i) { 73 if (desc[i].size_bits <= 32) { 74 int shift; 75 u32 val; 76 __be32 mask; 77 __be32 *addr; 78 79 shift = 32 - desc[i].offset_bits - desc[i].size_bits; 80 if (desc[i].struct_size_bytes) 81 val = value_read(desc[i].struct_offset_bytes, 82 desc[i].struct_size_bytes, 83 structure) << shift; 84 else 85 val = 0; 86 87 mask = cpu_to_be32(((1ull << desc[i].size_bits) - 1) << shift); 88 addr = (__be32 *) buf + desc[i].offset_words; 89 *addr = (*addr & ~mask) | (cpu_to_be32(val) & mask); 90 } else if (desc[i].size_bits <= 64) { 91 int shift; 92 u64 val; 93 __be64 mask; 94 __be64 *addr; 95 96 shift = 64 - desc[i].offset_bits - desc[i].size_bits; 97 if (desc[i].struct_size_bytes) 98 val = value_read(desc[i].struct_offset_bytes, 99 desc[i].struct_size_bytes, 100 structure) << shift; 101 else 102 val = 0; 103 104 mask = cpu_to_be64((~0ull >> (64 - desc[i].size_bits)) << shift); 105 addr = (__be64 *) ((__be32 *) buf + desc[i].offset_words); 106 *addr = (*addr & ~mask) | (cpu_to_be64(val) & mask); 107 } else { 108 if (desc[i].offset_bits % 8 || 109 desc[i].size_bits % 8) { 110 pr_warn("Structure field %s of size %d bits is not byte-aligned\n", 111 desc[i].field_name, desc[i].size_bits); 112 } 113 114 if (desc[i].struct_size_bytes) 115 memcpy((char *)buf + desc[i].offset_words * 4 + 116 desc[i].offset_bits / 8, 117 (char *)structure + desc[i].struct_offset_bytes, 118 desc[i].size_bits / 8); 119 else 120 memset((char *)buf + desc[i].offset_words * 4 + 121 desc[i].offset_bits / 8, 122 0, 123 desc[i].size_bits / 8); 124 } 125 } 126 } 127 EXPORT_SYMBOL(ib_pack); 128 129 static void value_write(int offset, int size, u64 val, void *structure) 130 { 131 switch (size * 8) { 132 case 8: *( u8 *) ((char *)structure + offset) = val; break; 133 case 16: *(__be16 *) ((char *)structure + offset) = cpu_to_be16(val); break; 134 case 32: *(__be32 *) ((char *)structure + offset) = cpu_to_be32(val); break; 135 case 64: *(__be64 *) ((char *)structure + offset) = cpu_to_be64(val); break; 136 default: 137 pr_warn("Field size %d bits not handled\n", size * 8); 138 } 139 } 140 141 /** 142 * ib_unpack - Unpack a buffer into a structure 143 * @desc:Array of structure field descriptions 144 * @desc_len:Number of entries in @desc 145 * @buf:Buffer to unpack from 146 * @structure:Structure to unpack into 147 * 148 * ib_pack() unpacks a list of structure fields from a buffer, 149 * controlled by the array of fields in @desc. 150 */ 151 void ib_unpack(const struct ib_field *desc, 152 int desc_len, 153 void *buf, 154 void *structure) 155 { 156 int i; 157 158 for (i = 0; i < desc_len; ++i) { 159 if (!desc[i].struct_size_bytes) 160 continue; 161 162 if (desc[i].size_bits <= 32) { 163 int shift; 164 u32 val; 165 u32 mask; 166 __be32 *addr; 167 168 shift = 32 - desc[i].offset_bits - desc[i].size_bits; 169 mask = ((1ull << desc[i].size_bits) - 1) << shift; 170 addr = (__be32 *) buf + desc[i].offset_words; 171 val = (be32_to_cpup(addr) & mask) >> shift; 172 value_write(desc[i].struct_offset_bytes, 173 desc[i].struct_size_bytes, 174 val, 175 structure); 176 } else if (desc[i].size_bits <= 64) { 177 int shift; 178 u64 val; 179 u64 mask; 180 __be64 *addr; 181 182 shift = 64 - desc[i].offset_bits - desc[i].size_bits; 183 mask = (~0ull >> (64 - desc[i].size_bits)) << shift; 184 addr = (__be64 *) buf + desc[i].offset_words; 185 val = (be64_to_cpup(addr) & mask) >> shift; 186 value_write(desc[i].struct_offset_bytes, 187 desc[i].struct_size_bytes, 188 val, 189 structure); 190 } else { 191 if (desc[i].offset_bits % 8 || 192 desc[i].size_bits % 8) { 193 pr_warn("Structure field %s of size %d bits is not byte-aligned\n", 194 desc[i].field_name, desc[i].size_bits); 195 } 196 197 memcpy((char *)structure + desc[i].struct_offset_bytes, 198 (char *)buf + desc[i].offset_words * 4 + 199 desc[i].offset_bits / 8, 200 desc[i].size_bits / 8); 201 } 202 } 203 } 204 EXPORT_SYMBOL(ib_unpack); 205