1 /*- 2 * Copyright (c) 1994 Bruce D. Evans. 3 * All rights reserved. 4 * 5 * Copyright (c) 1982, 1986, 1988 Regents of the University of California. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * from: @(#)ufs_disksubr.c 7.16 (Berkeley) 5/4/91 37 * from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $ 38 * $FreeBSD: src/sys/kern/subr_diskmbr.c,v 1.45 2000/01/28 10:22:07 bde Exp $ 39 * $DragonFly: src/sys/kern/subr_diskmbr.c,v 1.26 2007/06/19 06:07:57 dillon Exp $ 40 */ 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/buf.h> 45 #include <sys/conf.h> 46 #include <sys/diskslice.h> 47 #define DOSPTYP_EXTENDED 5 48 #define DOSPTYP_EXTENDEDX 15 49 #define DOSPTYP_ONTRACK 84 50 #include <sys/diskslice.h> 51 #include <sys/diskmbr.h> 52 #include <sys/disk.h> 53 #include <sys/malloc.h> 54 #include <sys/syslog.h> 55 #include <sys/device.h> 56 57 #define TRACE(str) do { if (dsi_debug) kprintf str; } while (0) 58 59 static volatile u_char dsi_debug; 60 61 /* 62 * This is what we have embedded in every boot1 for supporting the bogus 63 * "Dangerously Dedicated" mode. However, the old table is broken because 64 * it has an illegal geometry in it - it specifies 256 heads (heads = end 65 * head + 1) which causes nasty stuff when that wraps to zero in bios code. 66 * eg: divide by zero etc. This caused the dead-thinkpad problem, numerous 67 * SCSI bios crashes, EFI to crash, etc. 68 * 69 * We still have to recognize the old table though, even though we stopped 70 * inflicting it upon the world. 71 */ 72 static struct dos_partition historical_bogus_partition_table[NDOSPART] = { 73 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 74 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 75 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 76 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 255, 255, 255, 0, 50000, }, 77 }; 78 static struct dos_partition historical_bogus_partition_table_fixed[NDOSPART] = { 79 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 80 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 81 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 82 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 254, 255, 255, 0, 50000, }, 83 }; 84 85 static int check_part (char *sname, struct dos_partition *dp, 86 u_int64_t offset, int nsectors, int ntracks, 87 u_int64_t mbr_offset); 88 static void mbr_extended (cdev_t dev, struct disk_info *info, 89 struct diskslices *ssp, u_int64_t ext_offset, 90 u_int64_t ext_size, u_int64_t base_ext_offset, 91 int nsectors, int ntracks, u_int64_t mbr_offset, 92 int level); 93 static int mbr_setslice (char *sname, struct disk_info *info, 94 struct diskslice *sp, struct dos_partition *dp, 95 u_int64_t br_offset); 96 97 98 int 99 mbrinit(cdev_t dev, struct disk_info *info, struct diskslices **sspp) 100 { 101 struct buf *bp; 102 u_char *cp; 103 int dospart; 104 struct dos_partition *dp; 105 struct dos_partition *dp0; 106 struct dos_partition dpcopy[NDOSPART]; 107 int error; 108 int max_ncyls; 109 int max_nsectors; 110 int max_ntracks; 111 u_int64_t mbr_offset; 112 char partname[2]; 113 u_long secpercyl; 114 char *sname; 115 struct diskslice *sp; 116 struct diskslices *ssp; 117 cdev_t wdev; 118 119 mbr_offset = DOSBBSECTOR; 120 reread_mbr: 121 if (info->d_media_blksize & DEV_BMASK) 122 return (EIO); 123 /* Read master boot record. */ 124 wdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), WHOLE_SLICE_PART); 125 bp = geteblk((int)info->d_media_blksize); 126 bp->b_bio1.bio_offset = (off_t)mbr_offset * info->d_media_blksize; 127 bp->b_bcount = info->d_media_blksize; 128 bp->b_cmd = BUF_CMD_READ; 129 dev_dstrategy(wdev, &bp->b_bio1); 130 if (biowait(bp) != 0) { 131 diskerr(&bp->b_bio1, wdev, 132 "reading primary partition table: error", 133 LOG_PRINTF, 0); 134 kprintf("\n"); 135 error = EIO; 136 goto done; 137 } 138 139 /* Weakly verify it. */ 140 cp = bp->b_data; 141 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART, partname); 142 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { 143 if (bootverbose) 144 kprintf("%s: invalid primary partition table: no magic\n", 145 sname); 146 error = EINVAL; 147 goto done; 148 } 149 150 /* Make a copy of the partition table to avoid alignment problems. */ 151 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy)); 152 153 dp0 = &dpcopy[0]; 154 155 /* 156 * Check for "Ontrack Diskmanager" or GPT. If a GPT is found in 157 * the first dos partition, ignore the rest of the MBR and go 158 * to GPT processing. 159 */ 160 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 161 if (dospart == 0 && 162 (dp->dp_typ == DOSPTYP_PMBR || dp->dp_typ == DOSPTYP_GPT)) { 163 if (bootverbose) 164 kprintf( 165 "%s: Found GPT in slice #%d\n", sname, dospart + 1); 166 error = gptinit(dev, info, sspp); 167 goto done; 168 } 169 170 if (dp->dp_typ == DOSPTYP_ONTRACK) { 171 if (bootverbose) 172 kprintf( 173 "%s: Found \"Ontrack Disk Manager\" on this disk.\n", sname); 174 bp->b_flags |= B_INVAL | B_AGE; 175 brelse(bp); 176 mbr_offset = 63; 177 goto reread_mbr; 178 } 179 } 180 181 if (bcmp(dp0, historical_bogus_partition_table, 182 sizeof historical_bogus_partition_table) == 0 || 183 bcmp(dp0, historical_bogus_partition_table_fixed, 184 sizeof historical_bogus_partition_table_fixed) == 0) { 185 #if 0 186 TRACE(("%s: invalid primary partition table: historical\n", 187 sname)); 188 #endif /* 0 */ 189 if (bootverbose) 190 kprintf( 191 "%s: invalid primary partition table: Dangerously Dedicated (ignored)\n", 192 sname); 193 error = EINVAL; 194 goto done; 195 } 196 197 /* Guess the geometry. */ 198 /* 199 * TODO: 200 * Perhaps skip entries with 0 size. 201 * Perhaps only look at entries of type DOSPTYP_386BSD. 202 */ 203 max_ncyls = 0; 204 max_nsectors = 0; 205 max_ntracks = 0; 206 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 207 int ncyls; 208 int nsectors; 209 int ntracks; 210 211 ncyls = DPCYL(dp->dp_ecyl, dp->dp_esect) + 1; 212 if (max_ncyls < ncyls) 213 max_ncyls = ncyls; 214 nsectors = DPSECT(dp->dp_esect); 215 if (max_nsectors < nsectors) 216 max_nsectors = nsectors; 217 ntracks = dp->dp_ehd + 1; 218 if (max_ntracks < ntracks) 219 max_ntracks = ntracks; 220 } 221 222 /* 223 * Check that we have guessed the geometry right by checking the 224 * partition entries. 225 */ 226 /* 227 * TODO: 228 * As above. 229 * Check for overlaps. 230 * Check against d_secperunit if the latter is reliable. 231 */ 232 error = 0; 233 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 234 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 235 && dp->dp_start == 0 && dp->dp_size == 0) 236 continue; 237 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart, 238 WHOLE_SLICE_PART, partname); 239 240 /* 241 * Temporarily ignore errors from this check. We could 242 * simplify things by accepting the table eariler if we 243 * always ignore errors here. Perhaps we should always 244 * accept the table if the magic is right but not let 245 * bad entries affect the geometry. 246 */ 247 check_part(sname, dp, mbr_offset, max_nsectors, max_ntracks, 248 mbr_offset); 249 } 250 if (error != 0) 251 goto done; 252 253 /* 254 * Accept the DOS partition table. 255 * 256 * Adjust the disk information structure with updated CHS 257 * conversion parameters, but only use values extracted from 258 * the primary partition table. 259 * 260 * NOTE! Regardless of our having to deal with this old cruft, 261 * we do not screw around with the info->d_media* parameters. 262 */ 263 secpercyl = (u_long)max_nsectors * max_ntracks; 264 if (secpercyl != 0 && mbr_offset == DOSBBSECTOR) { 265 info->d_secpertrack = max_nsectors; 266 info->d_nheads = max_ntracks; 267 info->d_secpercyl = secpercyl; 268 info->d_ncylinders = info->d_media_blocks / secpercyl; 269 } 270 271 /* 272 * We are passed a pointer to a suitably initialized minimal 273 * slices "struct" with no dangling pointers in it. Replace it 274 * by a maximal one. This usually oversizes the "struct", but 275 * enlarging it while searching for logical drives would be 276 * inconvenient. 277 */ 278 kfree(*sspp, M_DEVBUF); 279 ssp = dsmakeslicestruct(MAX_SLICES, info); 280 *sspp = ssp; 281 282 /* Initialize normal slices. */ 283 sp = &ssp->dss_slices[BASE_SLICE]; 284 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) { 285 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart, 286 WHOLE_SLICE_PART, partname); 287 (void)mbr_setslice(sname, info, sp, dp, mbr_offset); 288 } 289 ssp->dss_nslices = BASE_SLICE + NDOSPART; 290 291 /* Handle extended partitions. */ 292 sp -= NDOSPART; 293 for (dospart = 0; dospart < NDOSPART; dospart++, sp++) { 294 if (sp->ds_type == DOSPTYP_EXTENDED || 295 sp->ds_type == DOSPTYP_EXTENDEDX) { 296 mbr_extended(wdev, info, ssp, 297 sp->ds_offset, sp->ds_size, sp->ds_offset, 298 max_nsectors, max_ntracks, mbr_offset, 1); 299 } 300 } 301 302 /* 303 * mbr_extended() abuses ssp->dss_nslices for the number of slices 304 * that would be found if there were no limit on the number of slices 305 * in *ssp. Cut it back now. 306 */ 307 if (ssp->dss_nslices > MAX_SLICES) 308 ssp->dss_nslices = MAX_SLICES; 309 310 done: 311 bp->b_flags |= B_INVAL | B_AGE; 312 brelse(bp); 313 if (error == EINVAL) 314 error = 0; 315 return (error); 316 } 317 318 static int 319 check_part(char *sname, struct dos_partition *dp, u_int64_t offset, 320 int nsectors, int ntracks, u_int64_t mbr_offset) 321 { 322 int chs_ecyl; 323 int chs_esect; 324 int chs_scyl; 325 int chs_ssect; 326 int error; 327 u_long secpercyl; 328 u_int64_t esector; 329 u_int64_t esector1; 330 u_int64_t ssector; 331 u_int64_t ssector1; 332 333 secpercyl = (u_long)nsectors * ntracks; 334 chs_scyl = DPCYL(dp->dp_scyl, dp->dp_ssect); 335 chs_ssect = DPSECT(dp->dp_ssect); 336 ssector = chs_ssect - 1 + dp->dp_shd * nsectors + chs_scyl * secpercyl 337 + mbr_offset; 338 ssector1 = offset + dp->dp_start; 339 340 /* 341 * If ssector1 is on a cylinder >= 1024, then ssector can't be right. 342 * Allow the C/H/S for it to be 1023/ntracks-1/nsectors, or correct 343 * apart from the cylinder being reduced modulo 1024. Always allow 344 * 1023/255/63, because this is the official way to represent 345 * pure-LBA for the starting position. 346 */ 347 if ((ssector < ssector1 348 && ((chs_ssect == nsectors && dp->dp_shd == ntracks - 1 349 && chs_scyl == 1023) 350 || (secpercyl != 0 351 && (ssector1 - ssector) % (1024 * secpercyl) == 0))) 352 || (dp->dp_scyl == 255 && dp->dp_shd == 255 353 && dp->dp_ssect == 255)) { 354 TRACE(("%s: C/H/S start %d/%d/%d, start %llu: allow\n", 355 sname, chs_scyl, dp->dp_shd, chs_ssect, 356 (long long)ssector1)); 357 ssector = ssector1; 358 } 359 360 chs_ecyl = DPCYL(dp->dp_ecyl, dp->dp_esect); 361 chs_esect = DPSECT(dp->dp_esect); 362 esector = chs_esect - 1 + dp->dp_ehd * nsectors + chs_ecyl * secpercyl 363 + mbr_offset; 364 esector1 = ssector1 + dp->dp_size - 1; 365 366 /* 367 * Allow certain bogus C/H/S values for esector, as above. However, 368 * heads == 255 isn't really legal and causes some BIOS crashes. The 369 * correct value to indicate a pure-LBA end is 1023/heads-1/sectors - 370 * usually 1023/254/63. "heads" is base 0, "sectors" is base 1. 371 */ 372 if ((esector < esector1 373 && ((chs_esect == nsectors && dp->dp_ehd == ntracks - 1 374 && chs_ecyl == 1023) 375 || (secpercyl != 0 376 && (esector1 - esector) % (1024 * secpercyl) == 0))) 377 || (dp->dp_ecyl == 255 && dp->dp_ehd == 255 378 && dp->dp_esect == 255)) { 379 TRACE(("%s: C/H/S end %d/%d/%d, end %llu: allow\n", 380 sname, chs_ecyl, dp->dp_ehd, chs_esect, 381 (long long)esector1)); 382 esector = esector1; 383 } 384 385 error = (ssector == ssector1 && esector == esector1) ? 0 : EINVAL; 386 if (bootverbose) 387 kprintf("%s: type 0x%x, start %llu, end = %llu, size %u %s\n", 388 sname, dp->dp_typ, 389 (long long)ssector1, (long long)esector1, 390 dp->dp_size, (error ? "" : ": OK")); 391 if (ssector != ssector1 && bootverbose) 392 kprintf("%s: C/H/S start %d/%d/%d (%llu) != start %llu: invalid\n", 393 sname, chs_scyl, dp->dp_shd, chs_ssect, 394 (long long)ssector, (long long)ssector1); 395 if (esector != esector1 && bootverbose) 396 kprintf("%s: C/H/S end %d/%d/%d (%llu) != end %llu: invalid\n", 397 sname, chs_ecyl, dp->dp_ehd, chs_esect, 398 (long long)esector, (long long)esector1); 399 return (error); 400 } 401 402 static 403 void 404 mbr_extended(cdev_t dev, struct disk_info *info, struct diskslices *ssp, 405 u_int64_t ext_offset, u_int64_t ext_size, u_int64_t base_ext_offset, 406 int nsectors, int ntracks, u_int64_t mbr_offset, int level) 407 { 408 struct buf *bp; 409 u_char *cp; 410 int dospart; 411 struct dos_partition *dp; 412 struct dos_partition dpcopy[NDOSPART]; 413 u_int64_t ext_offsets[NDOSPART]; 414 u_int64_t ext_sizes[NDOSPART]; 415 char partname[2]; 416 int slice; 417 char *sname; 418 struct diskslice *sp; 419 420 if (level >= 16) { 421 kprintf( 422 "%s: excessive recursion in search for slices; aborting search\n", 423 devtoname(dev)); 424 return; 425 } 426 427 /* Read extended boot record. */ 428 bp = geteblk((int)info->d_media_blksize); 429 bp->b_bio1.bio_offset = (off_t)ext_offset * info->d_media_blksize; 430 bp->b_bcount = info->d_media_blksize; 431 bp->b_cmd = BUF_CMD_READ; 432 dev_dstrategy(dev, &bp->b_bio1); 433 if (biowait(bp) != 0) { 434 diskerr(&bp->b_bio1, dev, 435 "reading extended partition table: error", 436 LOG_PRINTF, 0); 437 kprintf("\n"); 438 goto done; 439 } 440 441 /* Weakly verify it. */ 442 cp = bp->b_data; 443 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { 444 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART, 445 partname); 446 if (bootverbose) 447 kprintf("%s: invalid extended partition table: no magic\n", 448 sname); 449 goto done; 450 } 451 452 /* Make a copy of the partition table to avoid alignment problems. */ 453 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy)); 454 455 slice = ssp->dss_nslices; 456 for (dospart = 0, dp = &dpcopy[0]; dospart < NDOSPART; 457 dospart++, dp++) { 458 ext_sizes[dospart] = 0; 459 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 460 && dp->dp_start == 0 && dp->dp_size == 0) 461 continue; 462 if (dp->dp_typ == DOSPTYP_EXTENDED || 463 dp->dp_typ == DOSPTYP_EXTENDEDX) { 464 static char buf[32]; 465 466 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, 467 WHOLE_SLICE_PART, partname); 468 ksnprintf(buf, sizeof(buf), "%s", sname); 469 if (strlen(buf) < sizeof buf - 11) 470 strcat(buf, "<extended>"); 471 check_part(buf, dp, base_ext_offset, nsectors, 472 ntracks, mbr_offset); 473 ext_offsets[dospart] = base_ext_offset + dp->dp_start; 474 ext_sizes[dospart] = dp->dp_size; 475 } else { 476 sname = dsname(dev, dkunit(dev), slice, WHOLE_SLICE_PART, 477 partname); 478 check_part(sname, dp, ext_offset, nsectors, ntracks, 479 mbr_offset); 480 if (slice >= MAX_SLICES) { 481 kprintf("%s: too many slices\n", sname); 482 slice++; 483 continue; 484 } 485 sp = &ssp->dss_slices[slice]; 486 if (mbr_setslice(sname, info, sp, dp, ext_offset) != 0) 487 continue; 488 slice++; 489 } 490 } 491 ssp->dss_nslices = slice; 492 493 /* If we found any more slices, recursively find all the subslices. */ 494 for (dospart = 0; dospart < NDOSPART; dospart++) { 495 if (ext_sizes[dospart] != 0) { 496 mbr_extended(dev, info, ssp, ext_offsets[dospart], 497 ext_sizes[dospart], base_ext_offset, 498 nsectors, ntracks, mbr_offset, ++level); 499 } 500 } 501 502 done: 503 bp->b_flags |= B_INVAL | B_AGE; 504 brelse(bp); 505 } 506 507 static int 508 mbr_setslice(char *sname, struct disk_info *info, struct diskslice *sp, 509 struct dos_partition *dp, u_int64_t br_offset) 510 { 511 u_int64_t offset; 512 u_int64_t size; 513 514 offset = br_offset + dp->dp_start; 515 if (offset > info->d_media_blocks || offset < br_offset) { 516 kprintf( 517 "%s: slice starts beyond end of the disk: rejecting it\n", 518 sname); 519 return (1); 520 } 521 size = info->d_media_blocks - offset; 522 if (size >= dp->dp_size) { 523 if (dp->dp_size == 0xFFFFFFFFU) { 524 kprintf("%s: slice >2TB, using media size instead " 525 "of slice table size\n", sname); 526 } else { 527 size = dp->dp_size; 528 } 529 } else { 530 kprintf("%s: slice extends beyond end of disk: " 531 "truncating from %u to %llu sectors\n", 532 sname, dp->dp_size, (unsigned long long)size); 533 } 534 sp->ds_offset = offset; 535 sp->ds_size = size; 536 sp->ds_type = dp->dp_typ; 537 bzero(&sp->ds_type_uuid, sizeof(sp->ds_type_uuid)); 538 bzero(&sp->ds_stor_uuid, sizeof(sp->ds_type_uuid)); 539 540 /* 541 * Slices do not overlap with the parent (if any). 542 */ 543 sp->ds_reserved = 0; 544 return (0); 545 } 546