biosdisk.c revision 1.3
1 /* $NetBSD: biosdisk.c,v 1.3 2011/07/17 20:54:43 joerg Exp $ */ 2 3 /* 4 * Copyright (c) 1996, 1998 5 * Matthias Drochner. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 */ 28 29 /* 30 * raw BIOS disk device for libsa. 31 * needs lowlevel parts from bios_disk.S and biosdisk_ll.c 32 * partly from netbsd:sys/arch/i386/boot/disk.c 33 * no bad144 handling! 34 * 35 * A lot of this must match sys/kern/subr_disk_mbr.c 36 */ 37 38 /* 39 * Ported to boot 386BSD by Julian Elischer (julian (at) tfs.com) Sept 1992 40 * 41 * Mach Operating System 42 * Copyright (c) 1992, 1991 Carnegie Mellon University 43 * All Rights Reserved. 44 * 45 * Permission to use, copy, modify and distribute this software and its 46 * documentation is hereby granted, provided that both the copyright 47 * notice and this permission notice appear in all copies of the 48 * software, derivative works or modified versions, and any portions 49 * thereof, and that both notices appear in supporting documentation. 50 * 51 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 52 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 53 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 54 * 55 * Carnegie Mellon requests users of this software to return to 56 * 57 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU 58 * School of Computer Science 59 * Carnegie Mellon University 60 * Pittsburgh PA 15213-3890 61 * 62 * any improvements or extensions that they make and grant Carnegie Mellon 63 * the rights to redistribute these changes. 64 */ 65 66 #include <sys/types.h> 67 #include <sys/disklabel.h> 68 69 #include <lib/libsa/stand.h> 70 #include <lib/libsa/saerrno.h> 71 #include <lib/libsa/loadfile.h> 72 73 #include <machine/disklabel.h> 74 75 #include "biosdisk.h" 76 #include "biosdisk_ll.h" 77 78 #include "bootinfo.h" 79 80 #define BUFSIZE (1 * BIOSDISK_SECSIZE) 81 82 struct biosdisk { 83 int dev; 84 int boff; 85 char buf[BUFSIZE]; 86 }; 87 88 static struct btinfo_bootdisk bi_disk; 89 90 #define RF_PROTECTED_SECTORS 64 /* XXX refer to <.../rf_optnames.h> */ 91 92 static struct biosdisk * 93 alloc_biosdisk(int dev) 94 { 95 struct biosdisk *d; 96 97 d = (struct biosdisk *)ALLOC(sizeof(*d)); 98 if (d == NULL) 99 return (NULL); 100 101 memset(d, 0, sizeof(*d)); 102 d->dev = dev; 103 104 return (d); 105 } 106 107 static int 108 check_label(struct biosdisk *d, int sector) 109 { 110 struct disklabel *lp; 111 112 /* find partition in NetBSD disklabel */ 113 if (readsects(d->dev, sector + LABELSECTOR, d->buf, 1)) { 114 #ifdef DISK_DEBUG 115 printf("Error reading disklabel\n"); 116 #endif 117 return (EIO); 118 } 119 120 lp = (struct disklabel *)(d->buf + LABELOFFSET); 121 if (lp->d_magic != DISKMAGIC || dkcksum(lp)) { 122 #ifdef DISK_DEBUG 123 printf("warning: no disklabel\n"); 124 #endif 125 return (-1); 126 } 127 128 d->boff = sector; 129 return (0); 130 } 131 132 static int 133 read_label(struct biosdisk *d) 134 { 135 struct mbr_sector *mbr_sect; 136 struct disklabel dflt_lbl; 137 struct mbr_partition mbr[MBR_PART_COUNT]; 138 struct partition *p; 139 int sector, i; 140 int error; 141 int typ; 142 int ext_base, this_ext, next_ext; 143 #ifdef COMPAT_386BSD_MBRPART 144 int sector_386bsd = -1; 145 #endif 146 147 memset(&dflt_lbl, 0, sizeof dflt_lbl); 148 dflt_lbl.d_npartitions = 8; 149 150 d->boff = 0; 151 152 /* 153 * find NetBSD Partition in DOS partition table 154 * XXX check magic??? 155 */ 156 ext_base = 0; 157 next_ext = 0; 158 for (;;) { 159 this_ext = ext_base + next_ext; 160 next_ext = 0; 161 mbr_sect = (struct mbr_sector *)d->buf; 162 memcpy(&mbr, mbr_sect->mbr_parts, sizeof(mbr)); 163 if (readsects(d->dev, this_ext, d->buf, 1)) { 164 #ifdef DISK_DEBUG 165 printf("error reading MBR sector %d\n", this_ext); 166 #endif 167 return (EIO); 168 } 169 memcpy(&mbr, mbr_sect->mbr_parts, sizeof(mbr)); 170 /* Look for NetBSD partition ID */ 171 for (i = 0; i < MBR_PART_COUNT; i++) { 172 typ = mbr[i].mbrp_type; 173 if (typ == 0) 174 continue; 175 sector = this_ext + mbr[i].mbrp_start; 176 if (typ == MBR_PTYPE_NETBSD) { 177 error = check_label(d, sector); 178 if (error >= 0) 179 return error; 180 } 181 if (MBR_IS_EXTENDED(typ)) { 182 next_ext = mbr[i].mbrp_start; 183 continue; 184 } 185 #ifdef COMPAT_386BSD_MBRPART 186 if (this_ext == 0 && typ == MBR_PTYPE_386BSD) 187 sector_386bsd = sector; 188 #endif 189 if (this_ext != 0) { 190 if (dflt_lbl.d_npartitions >= MAXPARTITIONS) 191 continue; 192 p = &dflt_lbl.d_partitions[dflt_lbl.d_npartitions++]; 193 } else 194 p = &dflt_lbl.d_partitions[i]; 195 p->p_offset = sector; 196 p->p_size = mbr[i].mbrp_size; 197 p->p_fstype = xlat_mbr_fstype(typ); 198 } 199 if (next_ext == 0) 200 break; 201 if (ext_base == 0) { 202 ext_base = next_ext; 203 next_ext = 0; 204 } 205 } 206 207 sector = 0; 208 #ifdef COMPAT_386BSD_MBRPART 209 if (sector_386bsd != -1) { 210 printf("old BSD partition ID!\n"); 211 sector = sector_386bsd; 212 } 213 #endif 214 215 /* 216 * One of two things: 217 * 1. no MBR 218 * 2. no NetBSD partition in MBR 219 * 220 * We simply default to "start of disk" in this case and 221 * press on. 222 */ 223 error = check_label(d, sector); 224 if (error >= 0) 225 return (error); 226 227 /* 228 * Nothing at start of disk, return info from mbr partitions. 229 */ 230 /* XXX fill it to make checksum match kernel one */ 231 dflt_lbl.d_checksum = dkcksum(&dflt_lbl); 232 memcpy(d->buf, &dflt_lbl, sizeof(dflt_lbl)); 233 return (-1); 234 } 235 236 237 /* 238 * Determine likely partition for possible sector number of dos 239 * partition. 240 */ 241 u_int 242 biosdisk_findptn(int biosdev, u_int sector) 243 { 244 struct biosdisk *d; 245 u_int partition = 0; 246 struct disklabel *lp; 247 248 /* Look for netbsd partition that is the dos boot one */ 249 d = alloc_biosdisk(biosdev); 250 if (d == NULL) 251 return (0); 252 253 if (read_label(d) == 0) { 254 lp = (struct disklabel *)(d->buf + LABELOFFSET); 255 for (partition = lp->d_npartitions; --partition;){ 256 if (lp->d_partitions[partition].p_fstype == FS_UNUSED) 257 continue; 258 if (lp->d_partitions[partition].p_offset == sector) 259 break; 260 } 261 } 262 263 DEALLOC(d, sizeof(*d)); 264 return (partition); 265 } 266 267 int 268 biosdisk_open(struct open_file *f, ...) 269 { 270 va_list ap; 271 struct biosdisk *d; 272 struct disklabel *lp; 273 int dev; 274 int partition; 275 int error = 0; 276 277 va_start(ap, f); 278 dev = va_arg(ap, int); 279 d = alloc_biosdisk(dev); 280 if (d == NULL) { 281 error = ENXIO; 282 goto out; 283 } 284 285 partition = va_arg(ap, int); 286 bi_disk.biosdev = d->dev; 287 bi_disk.partition = partition; 288 bi_disk.labelsector = -1; 289 290 if (partition == RAW_PART) 291 goto nolabel; 292 error = read_label(d); 293 if (error == -1) { 294 error = 0; 295 goto nolabel; 296 } 297 if (error) 298 goto out; 299 300 lp = (struct disklabel *)(d->buf + LABELOFFSET); 301 if (partition >= lp->d_npartitions || 302 lp->d_partitions[partition].p_fstype == FS_UNUSED) { 303 #ifdef DISK_DEBUG 304 printf("illegal partition\n"); 305 #endif 306 error = EPART; 307 goto out; 308 } 309 bi_disk.labelsector = d->boff + LABELSECTOR; 310 bi_disk.label.type = lp->d_type; 311 memcpy(bi_disk.label.packname, lp->d_packname, 16); 312 bi_disk.label.checksum = lp->d_checksum; 313 314 d->boff = lp->d_partitions[partition].p_offset; 315 if (lp->d_partitions[partition].p_fstype == FS_RAID) { 316 d->boff += RF_PROTECTED_SECTORS; 317 } 318 nolabel: 319 320 #ifdef DISK_DEBUG 321 printf("partition @%d\n", d->boff); 322 #endif 323 324 BI_ADD(&bi_disk, BTINFO_BOOTDISK, sizeof(bi_disk)); 325 326 f->f_devdata = d; 327 out: 328 va_end(ap); 329 if (error) 330 DEALLOC(d, sizeof(struct biosdisk)); 331 return (error); 332 } 333 334 int 335 biosdisk_close(struct open_file *f) 336 { 337 struct biosdisk *d = f->f_devdata; 338 339 DEALLOC(d, sizeof(struct biosdisk)); 340 f->f_devdata = NULL; 341 342 return (0); 343 } 344 345 int 346 biosdisk_ioctl(struct open_file *f, u_long cmd, void *arg) 347 { 348 349 return (EIO); 350 } 351 352 int 353 biosdisk_strategy(void *devdata, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize) 354 { 355 struct biosdisk *d; 356 int blks; 357 int frag; 358 359 if (flag != F_READ) 360 return EROFS; 361 362 d = (struct biosdisk *)devdata; 363 364 dblk += d->boff; 365 366 blks = size / BIOSDISK_SECSIZE; 367 if (blks && readsects(d->dev, dblk, buf, blks)) { 368 if (rsize) 369 *rsize = 0; 370 return (EIO); 371 } 372 373 /* do we really need this? */ 374 frag = size % BIOSDISK_SECSIZE; 375 if (frag) { 376 if (readsects(d->dev, dblk + blks, d->buf, 1)) { 377 if (rsize) 378 *rsize = blks * BIOSDISK_SECSIZE; 379 return (EIO); 380 } 381 memcpy(buf + blks * BIOSDISK_SECSIZE, d->buf, frag); 382 } 383 384 if (rsize) 385 *rsize = size; 386 return (0); 387 } 388
Indexes created Wed Oct 22 00:09:40 GMT 2025