1 /* $NetBSD: v7fs_endian.c,v 1.2 2011/07/18 21:51:49 apb Exp $ */ 2 3 /*- 4 * Copyright (c) 2011 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by UCHIYAMA Yasushi. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #if HAVE_NBTOOL_CONFIG_H 33 #include "nbtool_config.h" 34 #endif 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: v7fs_endian.c,v 1.2 2011/07/18 21:51:49 apb Exp $"); 38 #if defined _KERNEL_OPT 39 #include "opt_v7fs.h" 40 #endif 41 42 #include "v7fs.h" 43 #include "v7fs_endian.h" 44 #include "v7fs_impl.h" 45 46 #ifndef BYTE_ORDER 47 #error 48 #endif 49 50 /* PDP to Little */ 51 #define bswap32pdp_le(x) \ 52 ((uint32_t) \ 53 ((((x) & 0xffff0000) >> 16) | \ 54 (((x) & 0x0000ffff) << 16))) 55 /* PDP to Big */ 56 #define bswap32pdp_be(x) \ 57 ((uint32_t) \ 58 ((((x) & 0xff00ff00) >> 8) | \ 59 (((x) & 0x00ff00ff) << 8))) 60 #ifdef V7FS_EI 61 static uint32_t val32_normal_order(uint32_t); 62 static uint32_t val32_reverse_order(uint32_t); 63 #if BYTE_ORDER == LITTLE_ENDIAN 64 static uint32_t val32_pdp_to_little(uint32_t); 65 #else 66 static uint32_t val32_pdp_to_big(uint32_t); 67 #endif 68 static uint16_t val16_normal_order(uint16_t); 69 static uint16_t val16_reverse_order(uint16_t); 70 static v7fs_daddr_t val24_reverse_order_read(uint8_t *); 71 static void val24_reverse_order_write(v7fs_daddr_t, uint8_t *); 72 static v7fs_daddr_t val24_pdp_read(uint8_t *); 73 static void val24_pdp_write(v7fs_daddr_t, uint8_t *); 74 75 static uint32_t 76 val32_normal_order(uint32_t v) 77 { 78 79 return v; 80 } 81 82 static uint32_t 83 val32_reverse_order(uint32_t v) 84 { 85 86 return bswap32(v); 87 } 88 #if BYTE_ORDER == LITTLE_ENDIAN 89 static uint32_t 90 val32_pdp_to_little(uint32_t v) 91 { 92 93 return bswap32pdp_le(v); 94 } 95 #else 96 static uint32_t 97 val32_pdp_to_big(uint32_t v) 98 { 99 100 return bswap32pdp_be(v); 101 } 102 #endif 103 static uint16_t 104 val16_normal_order(uint16_t v) 105 { 106 107 return v; 108 } 109 110 static uint16_t 111 val16_reverse_order(uint16_t v) 112 { 113 114 return bswap16(v); 115 } 116 117 static v7fs_daddr_t 118 val24_reverse_order_read(uint8_t *a) 119 { 120 #if BYTE_ORDER == LITTLE_ENDIAN 121 return (a[0] << 16) | (a[1] << 8) | a[2]; 122 #else 123 return (a[2] << 16) | (a[1] << 8) | a[0]; 124 #endif 125 } 126 127 static void 128 val24_reverse_order_write(v7fs_daddr_t addr, uint8_t *a) 129 { 130 #if BYTE_ORDER == LITTLE_ENDIAN 131 a[0] = (addr >> 16) & 0xff; 132 a[1] = (addr >> 8) & 0xff; 133 a[2] = addr & 0xff; 134 #else 135 a[0] = addr & 0xff; 136 a[1] = (addr >> 8) & 0xff; 137 a[2] = (addr >> 16) & 0xff; 138 #endif 139 } 140 141 static v7fs_daddr_t 142 val24_pdp_read(uint8_t *a) 143 { 144 145 return (a[0] << 16) | a[1] | (a[2] << 8); 146 } 147 148 static void 149 val24_pdp_write(v7fs_daddr_t addr, uint8_t *a) 150 { 151 152 a[0] = (addr >> 16) & 0xff; 153 a[1] = addr & 0xff; 154 a[2] = (addr >> 8) & 0xff; 155 } 156 157 void 158 v7fs_endian_init(struct v7fs_self *fs) 159 { 160 struct endian_conversion_ops *ops = &fs->val; 161 162 switch (fs->endian) 163 { 164 #if BYTE_ORDER == LITTLE_ENDIAN 165 case LITTLE_ENDIAN: 166 ops->conv32 = val32_normal_order; 167 ops->conv16 = val16_normal_order; 168 ops->conv24read = val24_normal_order_read; 169 ops->conv24write = val24_normal_order_write; 170 break; 171 case BIG_ENDIAN: 172 ops->conv32 = val32_reverse_order; 173 ops->conv16 = val16_reverse_order; 174 ops->conv24read = val24_reverse_order_read; 175 ops->conv24write = val24_reverse_order_write; 176 break; 177 case PDP_ENDIAN: 178 ops->conv32 = val32_pdp_to_little; 179 ops->conv16 = val16_normal_order; 180 ops->conv24read = val24_pdp_read; 181 ops->conv24write = val24_pdp_write; 182 break; 183 #else /* BIG_ENDIAN */ 184 case LITTLE_ENDIAN: 185 ops->conv32 = val32_reverse_order; 186 ops->conv16 = val16_reverse_order; 187 ops->conv24read = val24_reverse_order_read; 188 ops->conv24write = val24_reverse_order_write; 189 break; 190 case BIG_ENDIAN: 191 ops->conv32 = val32_normal_order; 192 ops->conv16 = val16_normal_order; 193 ops->conv24read = val24_normal_order_read; 194 ops->conv24write = val24_normal_order_write; 195 break; 196 case PDP_ENDIAN: 197 ops->conv32 = val32_pdp_to_big; 198 ops->conv16 = val16_reverse_order; 199 ops->conv24read = val24_pdp_read; 200 ops->conv24write = val24_pdp_write; 201 break; 202 #endif 203 } 204 } 205 #endif /* V7FS_EI */ 206 v7fs_daddr_t 207 val24_normal_order_read(uint8_t *a) 208 { 209 /*(v7fs_daddr_t)cast is required for int 16bit system. */ 210 #if BYTE_ORDER == LITTLE_ENDIAN 211 return ((v7fs_daddr_t)a[2] << 16) | ((v7fs_daddr_t)a[1] << 8) | 212 (v7fs_daddr_t)a[0]; 213 #else 214 return ((v7fs_daddr_t)a[0] << 16) | ((v7fs_daddr_t)a[1] << 8) | 215 (v7fs_daddr_t)a[2]; 216 #endif 217 } 218 219 void 220 val24_normal_order_write(v7fs_daddr_t addr, uint8_t *a) 221 { 222 #if BYTE_ORDER == LITTLE_ENDIAN 223 a[0] = addr & 0xff; 224 a[1] = (addr >> 8) & 0xff; 225 a[2] = (addr >> 16) & 0xff; 226 #else 227 a[0] = (addr >> 16) & 0xff; 228 a[1] = (addr >> 8) & 0xff; 229 a[2] = addr & 0xff; 230 #endif 231 } 232