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/string.h> 35 36 #include <rdma/ib_pack.h> 37 38 static u64 value_read(int offset, int size, void *structure) 39 { 40 switch (size) { 41 case 1: return *(u8 *) ((char *)structure + offset); 42 case 2: return be16_to_cpup((__be16 *) ((char *)structure + offset)); 43 case 4: return be32_to_cpup((__be32 *) ((char *)structure + offset)); 44 case 8: return be64_to_cpup((__be64 *) ((char *)structure + offset)); 45 default: 46 pr_warn("Field size %d bits not handled\n", size * 8); 47 return 0; 48 } 49 } 50 51 /** 52 * ib_pack - Pack a structure into a buffer 53 * @desc:Array of structure field descriptions 54 * @desc_len:Number of entries in @desc 55 * @structure:Structure to pack from 56 * @buf:Buffer to pack into 57 * 58 * ib_pack() packs a list of structure fields into a buffer, 59 * controlled by the array of fields in @desc. 60 */ 61 void ib_pack(const struct ib_field *desc, 62 int desc_len, 63 void *structure, 64 void *buf) 65 { 66 int i; 67 68 for (i = 0; i < desc_len; ++i) { 69 if (desc[i].size_bits <= 32) { 70 int shift; 71 u32 val; 72 __be32 mask; 73 __be32 *addr; 74 75 shift = 32 - desc[i].offset_bits - desc[i].size_bits; 76 if (desc[i].struct_size_bytes) 77 val = value_read(desc[i].struct_offset_bytes, 78 desc[i].struct_size_bytes, 79 structure) << shift; 80 else 81 val = 0; 82 83 mask = cpu_to_be32(((1ull << desc[i].size_bits) - 1) << shift); 84 addr = (__be32 *) buf + desc[i].offset_words; 85 *addr = (*addr & ~mask) | (cpu_to_be32(val) & mask); 86 } else if (desc[i].size_bits <= 64) { 87 int shift; 88 u64 val; 89 __be64 mask; 90 __be64 *addr; 91 92 shift = 64 - desc[i].offset_bits - desc[i].size_bits; 93 if (desc[i].struct_size_bytes) 94 val = value_read(desc[i].struct_offset_bytes, 95 desc[i].struct_size_bytes, 96 structure) << shift; 97 else 98 val = 0; 99 100 mask = cpu_to_be64((~0ull >> (64 - desc[i].size_bits)) << shift); 101 addr = (__be64 *) ((__be32 *) buf + desc[i].offset_words); 102 *addr = (*addr & ~mask) | (cpu_to_be64(val) & mask); 103 } else { 104 if (desc[i].offset_bits % 8 || 105 desc[i].size_bits % 8) { 106 pr_warn("Structure field %s of size %d bits is not byte-aligned\n", 107 desc[i].field_name, desc[i].size_bits); 108 } 109 110 if (desc[i].struct_size_bytes) 111 memcpy((char *)buf + desc[i].offset_words * 4 + 112 desc[i].offset_bits / 8, 113 (char *)structure + desc[i].struct_offset_bytes, 114 desc[i].size_bits / 8); 115 else 116 memset((char *)buf + desc[i].offset_words * 4 + 117 desc[i].offset_bits / 8, 118 0, 119 desc[i].size_bits / 8); 120 } 121 } 122 } 123 EXPORT_SYMBOL(ib_pack); 124 125 static void value_write(int offset, int size, u64 val, void *structure) 126 { 127 switch (size * 8) { 128 case 8: *( u8 *) ((char *)structure + offset) = val; break; 129 case 16: *(__be16 *) ((char *)structure + offset) = cpu_to_be16(val); break; 130 case 32: *(__be32 *) ((char *)structure + offset) = cpu_to_be32(val); break; 131 case 64: *(__be64 *) ((char *)structure + offset) = cpu_to_be64(val); break; 132 default: 133 pr_warn("Field size %d bits not handled\n", size * 8); 134 } 135 } 136 137 /** 138 * ib_unpack - Unpack a buffer into a structure 139 * @desc:Array of structure field descriptions 140 * @desc_len:Number of entries in @desc 141 * @buf:Buffer to unpack from 142 * @structure:Structure to unpack into 143 * 144 * ib_pack() unpacks a list of structure fields from a buffer, 145 * controlled by the array of fields in @desc. 146 */ 147 void ib_unpack(const struct ib_field *desc, 148 int desc_len, 149 void *buf, 150 void *structure) 151 { 152 int i; 153 154 for (i = 0; i < desc_len; ++i) { 155 if (!desc[i].struct_size_bytes) 156 continue; 157 158 if (desc[i].size_bits <= 32) { 159 int shift; 160 u32 val; 161 u32 mask; 162 __be32 *addr; 163 164 shift = 32 - desc[i].offset_bits - desc[i].size_bits; 165 mask = ((1ull << desc[i].size_bits) - 1) << shift; 166 addr = (__be32 *) buf + desc[i].offset_words; 167 val = (be32_to_cpup(addr) & mask) >> shift; 168 value_write(desc[i].struct_offset_bytes, 169 desc[i].struct_size_bytes, 170 val, 171 structure); 172 } else if (desc[i].size_bits <= 64) { 173 int shift; 174 u64 val; 175 u64 mask; 176 __be64 *addr; 177 178 shift = 64 - desc[i].offset_bits - desc[i].size_bits; 179 mask = (~0ull >> (64 - desc[i].size_bits)) << shift; 180 addr = (__be64 *) buf + desc[i].offset_words; 181 val = (be64_to_cpup(addr) & mask) >> shift; 182 value_write(desc[i].struct_offset_bytes, 183 desc[i].struct_size_bytes, 184 val, 185 structure); 186 } else { 187 if (desc[i].offset_bits % 8 || 188 desc[i].size_bits % 8) { 189 pr_warn("Structure field %s of size %d bits is not byte-aligned\n", 190 desc[i].field_name, desc[i].size_bits); 191 } 192 193 memcpy((char *)structure + desc[i].struct_offset_bytes, 194 (char *)buf + desc[i].offset_words * 4 + 195 desc[i].offset_bits / 8, 196 desc[i].size_bits / 8); 197 } 198 } 199 } 200 EXPORT_SYMBOL(ib_unpack); 201