1 /* $NetBSD: biosdisk.c,v 1.4 2021/05/17 19:31:38 mrg 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/libkern/libkern.h> 70 #include <lib/libsa/stand.h> 71 #include <lib/libsa/saerrno.h> 72 #include <lib/libsa/loadfile.h> 73 74 #include <machine/disklabel.h> 75 76 #include "biosdisk.h" 77 #include "biosdisk_ll.h" 78 79 #include "bootinfo.h" 80 81 #define BUFSIZE (1 * BIOSDISK_SECSIZE) 82 83 struct biosdisk { 84 int dev; 85 int boff; 86 char buf[BUFSIZE]; 87 }; 88 89 static struct btinfo_bootdisk bi_disk; 90 91 #define RF_PROTECTED_SECTORS 64 /* XXX refer to <.../rf_optnames.h> */ 92 93 static struct biosdisk * 94 alloc_biosdisk(int dev) 95 { 96 struct biosdisk *d; 97 98 d = (struct biosdisk *)ALLOC(sizeof(*d)); 99 if (d == NULL) 100 return (NULL); 101 102 memset(d, 0, sizeof(*d)); 103 d->dev = dev; 104 105 return (d); 106 } 107 108 static int 109 check_label(struct biosdisk *d, int sector) 110 { 111 struct disklabel *lp; 112 113 /* find partition in NetBSD disklabel */ 114 if (readsects(d->dev, sector + LABELSECTOR, d->buf, 1)) { 115 #ifdef DISK_DEBUG 116 printf("Error reading disklabel\n"); 117 #endif 118 return (EIO); 119 } 120 121 lp = (struct disklabel *)(d->buf + LABELOFFSET); 122 if (lp->d_magic != DISKMAGIC || dkcksum(lp)) { 123 #ifdef DISK_DEBUG 124 printf("warning: no disklabel\n"); 125 #endif 126 return (-1); 127 } 128 129 d->boff = sector; 130 return (0); 131 } 132 133 static int 134 read_label(struct biosdisk *d) 135 { 136 struct mbr_sector *mbr_sect; 137 struct disklabel dflt_lbl; 138 struct mbr_partition mbr[MBR_PART_COUNT]; 139 struct partition *p; 140 int sector, i; 141 int error; 142 int typ; 143 int ext_base, this_ext, next_ext; 144 #ifdef COMPAT_386BSD_MBRPART 145 int sector_386bsd = -1; 146 #endif 147 148 memset(&dflt_lbl, 0, sizeof dflt_lbl); 149 dflt_lbl.d_npartitions = 8; 150 151 d->boff = 0; 152 153 /* 154 * find NetBSD Partition in DOS partition table 155 * XXX check magic??? 156 */ 157 ext_base = 0; 158 next_ext = 0; 159 for (;;) { 160 this_ext = ext_base + next_ext; 161 next_ext = 0; 162 mbr_sect = (struct mbr_sector *)d->buf; 163 memcpy(&mbr, mbr_sect->mbr_parts, sizeof(mbr)); 164 if (readsects(d->dev, this_ext, d->buf, 1)) { 165 #ifdef DISK_DEBUG 166 printf("error reading MBR sector %d\n", this_ext); 167 #endif 168 return (EIO); 169 } 170 memcpy(&mbr, mbr_sect->mbr_parts, sizeof(mbr)); 171 /* Look for NetBSD partition ID */ 172 for (i = 0; i < MBR_PART_COUNT; i++) { 173 typ = mbr[i].mbrp_type; 174 if (typ == 0) 175 continue; 176 sector = this_ext + mbr[i].mbrp_start; 177 if (typ == MBR_PTYPE_NETBSD) { 178 error = check_label(d, sector); 179 if (error >= 0) 180 return error; 181 } 182 if (MBR_IS_EXTENDED(typ)) { 183 next_ext = mbr[i].mbrp_start; 184 continue; 185 } 186 #ifdef COMPAT_386BSD_MBRPART 187 if (this_ext == 0 && typ == MBR_PTYPE_386BSD) 188 sector_386bsd = sector; 189 #endif 190 if (this_ext != 0) { 191 if (dflt_lbl.d_npartitions >= MAXPARTITIONS) 192 continue; 193 p = &dflt_lbl.d_partitions[dflt_lbl.d_npartitions++]; 194 } else 195 p = &dflt_lbl.d_partitions[i]; 196 p->p_offset = sector; 197 p->p_size = mbr[i].mbrp_size; 198 p->p_fstype = xlat_mbr_fstype(typ); 199 } 200 if (next_ext == 0) 201 break; 202 if (ext_base == 0) { 203 ext_base = next_ext; 204 next_ext = 0; 205 } 206 } 207 208 sector = 0; 209 #ifdef COMPAT_386BSD_MBRPART 210 if (sector_386bsd != -1) { 211 printf("old BSD partition ID!\n"); 212 sector = sector_386bsd; 213 } 214 #endif 215 216 /* 217 * One of two things: 218 * 1. no MBR 219 * 2. no NetBSD partition in MBR 220 * 221 * We simply default to "start of disk" in this case and 222 * press on. 223 */ 224 error = check_label(d, sector); 225 if (error >= 0) 226 return (error); 227 228 /* 229 * Nothing at start of disk, return info from mbr partitions. 230 */ 231 /* XXX fill it to make checksum match kernel one */ 232 dflt_lbl.d_checksum = dkcksum(&dflt_lbl); 233 memcpy(d->buf, &dflt_lbl, sizeof(dflt_lbl)); 234 return (-1); 235 } 236 237 238 /* 239 * Determine likely partition for possible sector number of dos 240 * partition. 241 */ 242 u_int 243 biosdisk_findptn(int biosdev, u_int sector) 244 { 245 struct biosdisk *d; 246 u_int partition = 0; 247 struct disklabel *lp; 248 249 /* Look for netbsd partition that is the dos boot one */ 250 d = alloc_biosdisk(biosdev); 251 if (d == NULL) 252 return (0); 253 254 if (read_label(d) == 0) { 255 lp = (struct disklabel *)(d->buf + LABELOFFSET); 256 for (partition = lp->d_npartitions; --partition;){ 257 if (lp->d_partitions[partition].p_fstype == FS_UNUSED) 258 continue; 259 if (lp->d_partitions[partition].p_offset == sector) 260 break; 261 } 262 } 263 264 DEALLOC(d, sizeof(*d)); 265 return (partition); 266 } 267 268 int 269 biosdisk_open(struct open_file *f, ...) 270 { 271 va_list ap; 272 struct biosdisk *d; 273 struct disklabel *lp; 274 int dev; 275 int partition; 276 int error = 0; 277 278 va_start(ap, f); 279 dev = va_arg(ap, int); 280 d = alloc_biosdisk(dev); 281 if (d == NULL) { 282 error = ENXIO; 283 goto out; 284 } 285 286 partition = va_arg(ap, int); 287 bi_disk.biosdev = d->dev; 288 bi_disk.partition = partition; 289 bi_disk.labelsector = -1; 290 291 if (partition == RAW_PART) 292 goto nolabel; 293 error = read_label(d); 294 if (error == -1) { 295 error = 0; 296 goto nolabel; 297 } 298 if (error) 299 goto out; 300 301 lp = (struct disklabel *)(d->buf + LABELOFFSET); 302 if (partition >= lp->d_npartitions || 303 lp->d_partitions[partition].p_fstype == FS_UNUSED) { 304 #ifdef DISK_DEBUG 305 printf("illegal partition\n"); 306 #endif 307 error = EPART; 308 goto out; 309 } 310 bi_disk.labelsector = d->boff + LABELSECTOR; 311 bi_disk.label.type = lp->d_type; 312 memcpy(bi_disk.label.packname, lp->d_packname, 16); 313 bi_disk.label.checksum = lp->d_checksum; 314 315 d->boff = lp->d_partitions[partition].p_offset; 316 if (lp->d_partitions[partition].p_fstype == FS_RAID) { 317 d->boff += RF_PROTECTED_SECTORS; 318 } 319 nolabel: 320 321 #ifdef DISK_DEBUG 322 printf("partition @%d\n", d->boff); 323 #endif 324 325 BI_ADD(&bi_disk, BTINFO_BOOTDISK, sizeof(bi_disk)); 326 327 f->f_devdata = d; 328 out: 329 va_end(ap); 330 if (error) 331 DEALLOC(d, sizeof(struct biosdisk)); 332 return (error); 333 } 334 335 int 336 biosdisk_close(struct open_file *f) 337 { 338 struct biosdisk *d = f->f_devdata; 339 340 DEALLOC(d, sizeof(struct biosdisk)); 341 f->f_devdata = NULL; 342 343 return (0); 344 } 345 346 int 347 biosdisk_ioctl(struct open_file *f, u_long cmd, void *arg) 348 { 349 350 return (EIO); 351 } 352 353 int 354 biosdisk_strategy(void *devdata, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize) 355 { 356 struct biosdisk *d; 357 int blks; 358 int frag; 359 360 if (flag != F_READ) 361 return EROFS; 362 363 d = (struct biosdisk *)devdata; 364 365 dblk += d->boff; 366 367 blks = size / BIOSDISK_SECSIZE; 368 if (blks && readsects(d->dev, dblk, buf, blks)) { 369 if (rsize) 370 *rsize = 0; 371 return (EIO); 372 } 373 374 /* do we really need this? */ 375 frag = size % BIOSDISK_SECSIZE; 376 if (frag) { 377 if (readsects(d->dev, dblk + blks, d->buf, 1)) { 378 if (rsize) 379 *rsize = blks * BIOSDISK_SECSIZE; 380 return (EIO); 381 } 382 memcpy(buf + blks * BIOSDISK_SECSIZE, d->buf, frag); 383 } 384 385 if (rsize) 386 *rsize = size; 387 return (0); 388 } 389
Indexes created Sat Sep 27 22:09:54 GMT 2025