1 /* $NetBSD: biosdisk.c,v 1.1 2006/09/01 21:26:18 uwe 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@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@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/stdarg.h> 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 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 if (readsects(d->dev, this_ext, d->buf, 1)) { 162 #ifdef DISK_DEBUG 163 printf("error reading MBR sector %d\n", this_ext); 164 #endif 165 return (EIO); 166 } 167 memcpy(&mbr, ((struct mbr_sector *)d->buf)->mbr_parts, sizeof(mbr)); 168 /* Look for NetBSD partition ID */ 169 for (i = 0; i < MBR_PART_COUNT; i++) { 170 typ = mbr[i].mbrp_type; 171 if (typ == 0) 172 continue; 173 sector = this_ext + mbr[i].mbrp_start; 174 if (typ == MBR_PTYPE_NETBSD) { 175 error = check_label(d, sector); 176 if (error >= 0) 177 return error; 178 } 179 if (MBR_IS_EXTENDED(typ)) { 180 next_ext = mbr[i].mbrp_start; 181 continue; 182 } 183 #ifdef COMPAT_386BSD_MBRPART 184 if (this_ext == 0 && typ == MBR_PTYPE_386BSD) 185 sector_386bsd = sector; 186 #endif 187 if (this_ext != 0) { 188 if (dflt_lbl.d_npartitions >= MAXPARTITIONS) 189 continue; 190 p = &dflt_lbl.d_partitions[dflt_lbl.d_npartitions++]; 191 } else 192 p = &dflt_lbl.d_partitions[i]; 193 p->p_offset = sector; 194 p->p_size = mbr[i].mbrp_size; 195 p->p_fstype = xlat_mbr_fstype(typ); 196 } 197 if (next_ext == 0) 198 break; 199 if (ext_base == 0) { 200 ext_base = next_ext; 201 next_ext = 0; 202 } 203 } 204 205 sector = 0; 206 #ifdef COMPAT_386BSD_MBRPART 207 if (sector_386bsd != -1) { 208 printf("old BSD partition ID!\n"); 209 sector = sector_386bsd; 210 } 211 #endif 212 213 /* 214 * One of two things: 215 * 1. no MBR 216 * 2. no NetBSD partition in MBR 217 * 218 * We simply default to "start of disk" in this case and 219 * press on. 220 */ 221 error = check_label(d, sector); 222 if (error >= 0) 223 return (error); 224 225 /* 226 * Nothing at start of disk, return info from mbr partitions. 227 */ 228 /* XXX fill it to make checksum match kernel one */ 229 dflt_lbl.d_checksum = dkcksum(&dflt_lbl); 230 memcpy(d->buf, &dflt_lbl, sizeof(dflt_lbl)); 231 return (-1); 232 } 233 234 235 /* 236 * Determine likely partition for possible sector number of dos 237 * partition. 238 */ 239 u_int 240 biosdisk_findptn(int biosdev, u_int sector) 241 { 242 struct biosdisk *d; 243 u_int partition = 0; 244 struct disklabel *lp; 245 246 /* Look for netbsd partition that is the dos boot one */ 247 d = alloc_biosdisk(biosdev); 248 if (d == NULL) 249 return (0); 250 251 if (read_label(d) == 0) { 252 lp = (struct disklabel *)(d->buf + LABELOFFSET); 253 for (partition = lp->d_npartitions; --partition;){ 254 if (lp->d_partitions[partition].p_fstype == FS_UNUSED) 255 continue; 256 if (lp->d_partitions[partition].p_offset == sector) 257 break; 258 } 259 } 260 261 DEALLOC(d, sizeof(*d)); 262 return (partition); 263 } 264 265 int 266 biosdisk_open(struct open_file *f, ...) 267 { 268 va_list ap; 269 struct biosdisk *d; 270 struct disklabel *lp; 271 int dev; 272 int partition; 273 int error = 0; 274 275 va_start(ap, f); 276 dev = va_arg(ap, int); 277 d = alloc_biosdisk(dev); 278 if (d == NULL) { 279 error = ENXIO; 280 goto out; 281 } 282 283 partition = va_arg(ap, int); 284 bi_disk.biosdev = d->dev; 285 bi_disk.partition = partition; 286 bi_disk.labelsector = -1; 287 288 if (partition == RAW_PART) 289 goto nolabel; 290 error = read_label(d); 291 if (error == -1) { 292 error = 0; 293 goto nolabel; 294 } 295 if (error) 296 goto out; 297 298 lp = (struct disklabel *)(d->buf + LABELOFFSET); 299 if (partition >= lp->d_npartitions || 300 lp->d_partitions[partition].p_fstype == FS_UNUSED) { 301 #ifdef DISK_DEBUG 302 printf("illegal partition\n"); 303 #endif 304 error = EPART; 305 goto out; 306 } 307 bi_disk.labelsector = d->boff + LABELSECTOR; 308 bi_disk.label.type = lp->d_type; 309 memcpy(bi_disk.label.packname, lp->d_packname, 16); 310 bi_disk.label.checksum = lp->d_checksum; 311 312 d->boff = lp->d_partitions[partition].p_offset; 313 if (lp->d_partitions[partition].p_fstype == FS_RAID) { 314 d->boff += RF_PROTECTED_SECTORS; 315 } 316 nolabel: 317 318 #ifdef DISK_DEBUG 319 printf("partition @%d\n", d->boff); 320 #endif 321 322 BI_ADD(&bi_disk, BTINFO_BOOTDISK, sizeof(bi_disk)); 323 324 f->f_devdata = d; 325 out: 326 va_end(ap); 327 if (error) 328 DEALLOC(d, sizeof(struct biosdisk)); 329 return (error); 330 } 331 332 int 333 biosdisk_close(struct open_file *f) 334 { 335 struct biosdisk *d = f->f_devdata; 336 337 DEALLOC(d, sizeof(struct biosdisk)); 338 f->f_devdata = NULL; 339 340 return (0); 341 } 342 343 int 344 biosdisk_ioctl(struct open_file *f, u_long cmd, void *arg) 345 { 346 347 return (EIO); 348 } 349 350 int 351 biosdisk_strategy(void *devdata, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize) 352 { 353 struct biosdisk *d; 354 int blks; 355 int frag; 356 357 if (flag != F_READ) 358 return EROFS; 359 360 d = (struct biosdisk *)devdata; 361 362 dblk += d->boff; 363 364 blks = size / BIOSDISK_SECSIZE; 365 if (blks && readsects(d->dev, dblk, buf, blks)) { 366 if (rsize) 367 *rsize = 0; 368 return (EIO); 369 } 370 371 /* do we really need this? */ 372 frag = size % BIOSDISK_SECSIZE; 373 if (frag) { 374 if (readsects(d->dev, dblk + blks, d->buf, 1)) { 375 if (rsize) 376 *rsize = blks * BIOSDISK_SECSIZE; 377 return (EIO); 378 } 379 memcpy(buf + blks * BIOSDISK_SECSIZE, d->buf, frag); 380 } 381 382 if (rsize) 383 *rsize = size; 384 return (0); 385 } 386