packer.c (6389B)
1/* 2 * Copyright (c) 2004 Topspin Corporation. All rights reserved. 3 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved. 4 * 5 * This software is available to you under a choice of one of two 6 * licenses. You may choose to be licensed under the terms of the GNU 7 * General Public License (GPL) Version 2, available from the file 8 * COPYING in the main directory of this source tree, or the 9 * OpenIB.org BSD license below: 10 * 11 * Redistribution and use in source and binary forms, with or 12 * without modification, are permitted provided that the following 13 * conditions are met: 14 * 15 * - Redistributions of source code must retain the above 16 * copyright notice, this list of conditions and the following 17 * disclaimer. 18 * 19 * - Redistributions in binary form must reproduce the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer in the documentation and/or other materials 22 * provided with the distribution. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 31 * SOFTWARE. 32 */ 33 34#include <linux/export.h> 35#include <linux/string.h> 36 37#include <rdma/ib_pack.h> 38 39static u64 value_read(int offset, int size, void *structure) 40{ 41 switch (size) { 42 case 1: return *(u8 *) (structure + offset); 43 case 2: return be16_to_cpup((__be16 *) (structure + offset)); 44 case 4: return be32_to_cpup((__be32 *) (structure + offset)); 45 case 8: return be64_to_cpup((__be64 *) (structure + offset)); 46 default: 47 pr_warn("Field size %d bits not handled\n", size * 8); 48 return 0; 49 } 50} 51 52/** 53 * ib_pack - Pack a structure into a buffer 54 * @desc:Array of structure field descriptions 55 * @desc_len:Number of entries in @desc 56 * @structure:Structure to pack from 57 * @buf:Buffer to pack into 58 * 59 * ib_pack() packs a list of structure fields into a buffer, 60 * controlled by the array of fields in @desc. 61 */ 62void ib_pack(const struct ib_field *desc, 63 int desc_len, 64 void *structure, 65 void *buf) 66{ 67 int i; 68 69 for (i = 0; i < desc_len; ++i) { 70 if (desc[i].size_bits <= 32) { 71 int shift; 72 u32 val; 73 __be32 mask; 74 __be32 *addr; 75 76 shift = 32 - desc[i].offset_bits - desc[i].size_bits; 77 if (desc[i].struct_size_bytes) 78 val = value_read(desc[i].struct_offset_bytes, 79 desc[i].struct_size_bytes, 80 structure) << shift; 81 else 82 val = 0; 83 84 mask = cpu_to_be32(((1ull << desc[i].size_bits) - 1) << shift); 85 addr = (__be32 *) buf + desc[i].offset_words; 86 *addr = (*addr & ~mask) | (cpu_to_be32(val) & mask); 87 } else if (desc[i].size_bits <= 64) { 88 int shift; 89 u64 val; 90 __be64 mask; 91 __be64 *addr; 92 93 shift = 64 - desc[i].offset_bits - desc[i].size_bits; 94 if (desc[i].struct_size_bytes) 95 val = value_read(desc[i].struct_offset_bytes, 96 desc[i].struct_size_bytes, 97 structure) << shift; 98 else 99 val = 0; 100 101 mask = cpu_to_be64((~0ull >> (64 - desc[i].size_bits)) << shift); 102 addr = (__be64 *) ((__be32 *) buf + desc[i].offset_words); 103 *addr = (*addr & ~mask) | (cpu_to_be64(val) & mask); 104 } else { 105 if (desc[i].offset_bits % 8 || 106 desc[i].size_bits % 8) { 107 pr_warn("Structure field %s of size %d bits is not byte-aligned\n", 108 desc[i].field_name, desc[i].size_bits); 109 } 110 111 if (desc[i].struct_size_bytes) 112 memcpy(buf + desc[i].offset_words * 4 + 113 desc[i].offset_bits / 8, 114 structure + desc[i].struct_offset_bytes, 115 desc[i].size_bits / 8); 116 else 117 memset(buf + desc[i].offset_words * 4 + 118 desc[i].offset_bits / 8, 119 0, 120 desc[i].size_bits / 8); 121 } 122 } 123} 124EXPORT_SYMBOL(ib_pack); 125 126static void value_write(int offset, int size, u64 val, void *structure) 127{ 128 switch (size * 8) { 129 case 8: *( u8 *) (structure + offset) = val; break; 130 case 16: *(__be16 *) (structure + offset) = cpu_to_be16(val); break; 131 case 32: *(__be32 *) (structure + offset) = cpu_to_be32(val); break; 132 case 64: *(__be64 *) (structure + offset) = cpu_to_be64(val); break; 133 default: 134 pr_warn("Field size %d bits not handled\n", size * 8); 135 } 136} 137 138/** 139 * ib_unpack - Unpack a buffer into a structure 140 * @desc:Array of structure field descriptions 141 * @desc_len:Number of entries in @desc 142 * @buf:Buffer to unpack from 143 * @structure:Structure to unpack into 144 * 145 * ib_pack() unpacks a list of structure fields from a buffer, 146 * controlled by the array of fields in @desc. 147 */ 148void ib_unpack(const struct ib_field *desc, 149 int desc_len, 150 void *buf, 151 void *structure) 152{ 153 int i; 154 155 for (i = 0; i < desc_len; ++i) { 156 if (!desc[i].struct_size_bytes) 157 continue; 158 159 if (desc[i].size_bits <= 32) { 160 int shift; 161 u32 val; 162 u32 mask; 163 __be32 *addr; 164 165 shift = 32 - desc[i].offset_bits - desc[i].size_bits; 166 mask = ((1ull << desc[i].size_bits) - 1) << shift; 167 addr = (__be32 *) buf + desc[i].offset_words; 168 val = (be32_to_cpup(addr) & mask) >> shift; 169 value_write(desc[i].struct_offset_bytes, 170 desc[i].struct_size_bytes, 171 val, 172 structure); 173 } else if (desc[i].size_bits <= 64) { 174 int shift; 175 u64 val; 176 u64 mask; 177 __be64 *addr; 178 179 shift = 64 - desc[i].offset_bits - desc[i].size_bits; 180 mask = (~0ull >> (64 - desc[i].size_bits)) << shift; 181 addr = (__be64 *) buf + desc[i].offset_words; 182 val = (be64_to_cpup(addr) & mask) >> shift; 183 value_write(desc[i].struct_offset_bytes, 184 desc[i].struct_size_bytes, 185 val, 186 structure); 187 } else { 188 if (desc[i].offset_bits % 8 || 189 desc[i].size_bits % 8) { 190 pr_warn("Structure field %s of size %d bits is not byte-aligned\n", 191 desc[i].field_name, desc[i].size_bits); 192 } 193 194 memcpy(structure + desc[i].struct_offset_bytes, 195 buf + desc[i].offset_words * 4 + 196 desc[i].offset_bits / 8, 197 desc[i].size_bits / 8); 198 } 199 } 200} 201EXPORT_SYMBOL(ib_unpack);