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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 two6 * licenses. You may choose to be licensed under the terms of the GNU7 * General Public License (GPL) Version 2, available from the file8 * COPYING in the main directory of this source tree, or the9 * OpenIB.org BSD license below:10 *11 * Redistribution and use in source and binary forms, with or12 * without modification, are permitted provided that the following13 * conditions are met:14 *15 * - Redistributions of source code must retain the above16 * copyright notice, this list of conditions and the following17 * disclaimer.18 *19 * - Redistributions in binary form must reproduce the above20 * copyright notice, this list of conditions and the following21 * disclaimer in the documentation and/or other materials22 * 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 OF26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE31 * 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 buffer54 * @desc:Array of structure field descriptions55 * @desc_len:Number of entries in @desc56 * @structure:Structure to pack from57 * @buf:Buffer to pack into58 *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 else82 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 else99 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 else117 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 structure140 * @desc:Array of structure field descriptions141 * @desc_len:Number of entries in @desc142 * @buf:Buffer to unpack from143 * @structure:Structure to unpack into144 *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);202