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_bio1.bio_done = biodone_sync; 128 bp->b_bio1.bio_flags |= BIO_SYNC; 129 bp->b_bcount = info->d_media_blksize; 130 bp->b_cmd = BUF_CMD_READ; 131 dev_dstrategy(wdev, &bp->b_bio1); 132 if (biowait(&bp->b_bio1, "mbrrd") != 0) { 133 diskerr(&bp->b_bio1, wdev, 134 "reading primary partition table: error", 135 LOG_PRINTF, 0); 136 kprintf("\n"); 137 error = EIO; 138 goto done; 139 } 140 141 /* Weakly verify it. */ 142 cp = bp->b_data; 143 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART, partname); 144 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { 145 if (bootverbose) 146 kprintf("%s: invalid primary partition table: no magic\n", 147 sname); 148 error = EINVAL; 149 goto done; 150 } 151 152 /* Make a copy of the partition table to avoid alignment problems. */ 153 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy)); 154 155 dp0 = &dpcopy[0]; 156 157 /* 158 * Check for "Ontrack Diskmanager" or GPT. If a GPT is found in 159 * the first dos partition, ignore the rest of the MBR and go 160 * to GPT processing. 161 */ 162 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 163 if (dospart == 0 && 164 (dp->dp_typ == DOSPTYP_PMBR || dp->dp_typ == DOSPTYP_GPT)) { 165 if (bootverbose) 166 kprintf( 167 "%s: Found GPT in slice #%d\n", sname, dospart + 1); 168 error = gptinit(dev, info, sspp); 169 goto done; 170 } 171 172 if (dp->dp_typ == DOSPTYP_ONTRACK) { 173 if (bootverbose) 174 kprintf( 175 "%s: Found \"Ontrack Disk Manager\" on this disk.\n", sname); 176 bp->b_flags |= B_INVAL | B_AGE; 177 brelse(bp); 178 mbr_offset = 63; 179 goto reread_mbr; 180 } 181 } 182 183 if (bcmp(dp0, historical_bogus_partition_table, 184 sizeof historical_bogus_partition_table) == 0 || 185 bcmp(dp0, historical_bogus_partition_table_fixed, 186 sizeof historical_bogus_partition_table_fixed) == 0) { 187 #if 0 188 TRACE(("%s: invalid primary partition table: historical\n", 189 sname)); 190 #endif /* 0 */ 191 if (bootverbose) 192 kprintf( 193 "%s: invalid primary partition table: Dangerously Dedicated (ignored)\n", 194 sname); 195 error = EINVAL; 196 goto done; 197 } 198 199 /* Guess the geometry. */ 200 /* 201 * TODO: 202 * Perhaps skip entries with 0 size. 203 * Perhaps only look at entries of type DOSPTYP_386BSD. 204 */ 205 max_ncyls = 0; 206 max_nsectors = 0; 207 max_ntracks = 0; 208 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 209 int ncyls; 210 int nsectors; 211 int ntracks; 212 213 ncyls = DPCYL(dp->dp_ecyl, dp->dp_esect) + 1; 214 if (max_ncyls < ncyls) 215 max_ncyls = ncyls; 216 nsectors = DPSECT(dp->dp_esect); 217 if (max_nsectors < nsectors) 218 max_nsectors = nsectors; 219 ntracks = dp->dp_ehd + 1; 220 if (max_ntracks < ntracks) 221 max_ntracks = ntracks; 222 } 223 224 /* 225 * Check that we have guessed the geometry right by checking the 226 * partition entries. 227 */ 228 /* 229 * TODO: 230 * As above. 231 * Check for overlaps. 232 * Check against d_secperunit if the latter is reliable. 233 */ 234 error = 0; 235 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 236 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 237 && dp->dp_start == 0 && dp->dp_size == 0) 238 continue; 239 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart, 240 WHOLE_SLICE_PART, partname); 241 242 /* 243 * Temporarily ignore errors from this check. We could 244 * simplify things by accepting the table eariler if we 245 * always ignore errors here. Perhaps we should always 246 * accept the table if the magic is right but not let 247 * bad entries affect the geometry. 248 */ 249 check_part(sname, dp, mbr_offset, max_nsectors, max_ntracks, 250 mbr_offset); 251 } 252 if (error != 0) 253 goto done; 254 255 /* 256 * Accept the DOS partition table. 257 * 258 * Adjust the disk information structure with updated CHS 259 * conversion parameters, but only use values extracted from 260 * the primary partition table. 261 * 262 * NOTE! Regardless of our having to deal with this old cruft, 263 * we do not screw around with the info->d_media* parameters. 264 */ 265 secpercyl = (u_long)max_nsectors * max_ntracks; 266 if (secpercyl != 0 && mbr_offset == DOSBBSECTOR) { 267 info->d_secpertrack = max_nsectors; 268 info->d_nheads = max_ntracks; 269 info->d_secpercyl = secpercyl; 270 info->d_ncylinders = info->d_media_blocks / secpercyl; 271 } 272 273 /* 274 * We are passed a pointer to a suitably initialized minimal 275 * slices "struct" with no dangling pointers in it. Replace it 276 * by a maximal one. This usually oversizes the "struct", but 277 * enlarging it while searching for logical drives would be 278 * inconvenient. 279 */ 280 kfree(*sspp, M_DEVBUF); 281 ssp = dsmakeslicestruct(MAX_SLICES, info); 282 *sspp = ssp; 283 284 /* Initialize normal slices. */ 285 sp = &ssp->dss_slices[BASE_SLICE]; 286 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) { 287 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart, 288 WHOLE_SLICE_PART, partname); 289 (void)mbr_setslice(sname, info, sp, dp, mbr_offset); 290 } 291 ssp->dss_nslices = BASE_SLICE + NDOSPART; 292 293 /* Handle extended partitions. */ 294 sp -= NDOSPART; 295 for (dospart = 0; dospart < NDOSPART; dospart++, sp++) { 296 if (sp->ds_type == DOSPTYP_EXTENDED || 297 sp->ds_type == DOSPTYP_EXTENDEDX) { 298 mbr_extended(wdev, info, ssp, 299 sp->ds_offset, sp->ds_size, sp->ds_offset, 300 max_nsectors, max_ntracks, mbr_offset, 1); 301 } 302 } 303 304 /* 305 * mbr_extended() abuses ssp->dss_nslices for the number of slices 306 * that would be found if there were no limit on the number of slices 307 * in *ssp. Cut it back now. 308 */ 309 if (ssp->dss_nslices > MAX_SLICES) 310 ssp->dss_nslices = MAX_SLICES; 311 312 done: 313 bp->b_flags |= B_INVAL | B_AGE; 314 brelse(bp); 315 if (error == EINVAL) 316 error = 0; 317 return (error); 318 } 319 320 static int 321 check_part(char *sname, struct dos_partition *dp, u_int64_t offset, 322 int nsectors, int ntracks, u_int64_t mbr_offset) 323 { 324 int chs_ecyl; 325 int chs_esect; 326 int chs_scyl; 327 int chs_ssect; 328 int error; 329 u_long secpercyl; 330 u_int64_t esector; 331 u_int64_t esector1; 332 u_int64_t ssector; 333 u_int64_t ssector1; 334 335 secpercyl = (u_long)nsectors * ntracks; 336 chs_scyl = DPCYL(dp->dp_scyl, dp->dp_ssect); 337 chs_ssect = DPSECT(dp->dp_ssect); 338 ssector = chs_ssect - 1 + dp->dp_shd * nsectors + chs_scyl * secpercyl 339 + mbr_offset; 340 ssector1 = offset + dp->dp_start; 341 342 /* 343 * If ssector1 is on a cylinder >= 1024, then ssector can't be right. 344 * Allow the C/H/S for it to be 1023/ntracks-1/nsectors, or correct 345 * apart from the cylinder being reduced modulo 1024. Always allow 346 * 1023/255/63, because this is the official way to represent 347 * pure-LBA for the starting position. 348 */ 349 if ((ssector < ssector1 350 && ((chs_ssect == nsectors && dp->dp_shd == ntracks - 1 351 && chs_scyl == 1023) 352 || (secpercyl != 0 353 && (ssector1 - ssector) % (1024 * secpercyl) == 0))) 354 || (dp->dp_scyl == 255 && dp->dp_shd == 255 355 && dp->dp_ssect == 255)) { 356 TRACE(("%s: C/H/S start %d/%d/%d, start %llu: allow\n", 357 sname, chs_scyl, dp->dp_shd, chs_ssect, 358 (long long)ssector1)); 359 ssector = ssector1; 360 } 361 362 chs_ecyl = DPCYL(dp->dp_ecyl, dp->dp_esect); 363 chs_esect = DPSECT(dp->dp_esect); 364 esector = chs_esect - 1 + dp->dp_ehd * nsectors + chs_ecyl * secpercyl 365 + mbr_offset; 366 esector1 = ssector1 + dp->dp_size - 1; 367 368 /* 369 * Allow certain bogus C/H/S values for esector, as above. However, 370 * heads == 255 isn't really legal and causes some BIOS crashes. The 371 * correct value to indicate a pure-LBA end is 1023/heads-1/sectors - 372 * usually 1023/254/63. "heads" is base 0, "sectors" is base 1. 373 */ 374 if ((esector < esector1 375 && ((chs_esect == nsectors && dp->dp_ehd == ntracks - 1 376 && chs_ecyl == 1023) 377 || (secpercyl != 0 378 && (esector1 - esector) % (1024 * secpercyl) == 0))) 379 || (dp->dp_ecyl == 255 && dp->dp_ehd == 255 380 && dp->dp_esect == 255)) { 381 TRACE(("%s: C/H/S end %d/%d/%d, end %llu: allow\n", 382 sname, chs_ecyl, dp->dp_ehd, chs_esect, 383 (long long)esector1)); 384 esector = esector1; 385 } 386 387 error = (ssector == ssector1 && esector == esector1) ? 0 : EINVAL; 388 if (bootverbose) 389 kprintf("%s: type 0x%x, start %llu, end = %llu, size %u %s\n", 390 sname, dp->dp_typ, 391 (long long)ssector1, (long long)esector1, 392 dp->dp_size, (error ? "" : ": OK")); 393 if (ssector != ssector1 && bootverbose) 394 kprintf("%s: C/H/S start %d/%d/%d (%llu) != start %llu: invalid\n", 395 sname, chs_scyl, dp->dp_shd, chs_ssect, 396 (long long)ssector, (long long)ssector1); 397 if (esector != esector1 && bootverbose) 398 kprintf("%s: C/H/S end %d/%d/%d (%llu) != end %llu: invalid\n", 399 sname, chs_ecyl, dp->dp_ehd, chs_esect, 400 (long long)esector, (long long)esector1); 401 return (error); 402 } 403 404 static 405 void 406 mbr_extended(cdev_t dev, struct disk_info *info, struct diskslices *ssp, 407 u_int64_t ext_offset, u_int64_t ext_size, u_int64_t base_ext_offset, 408 int nsectors, int ntracks, u_int64_t mbr_offset, int level) 409 { 410 struct buf *bp; 411 u_char *cp; 412 int dospart; 413 struct dos_partition *dp; 414 struct dos_partition dpcopy[NDOSPART]; 415 u_int64_t ext_offsets[NDOSPART]; 416 u_int64_t ext_sizes[NDOSPART]; 417 char partname[2]; 418 int slice; 419 char *sname; 420 struct diskslice *sp; 421 422 if (level >= 16) { 423 kprintf( 424 "%s: excessive recursion in search for slices; aborting search\n", 425 devtoname(dev)); 426 return; 427 } 428 429 /* Read extended boot record. */ 430 bp = geteblk((int)info->d_media_blksize); 431 bp->b_bio1.bio_offset = (off_t)ext_offset * info->d_media_blksize; 432 bp->b_bio1.bio_done = biodone_sync; 433 bp->b_bio1.bio_flags |= BIO_SYNC; 434 bp->b_bcount = info->d_media_blksize; 435 bp->b_cmd = BUF_CMD_READ; 436 dev_dstrategy(dev, &bp->b_bio1); 437 if (biowait(&bp->b_bio1, "mbrrd") != 0) { 438 diskerr(&bp->b_bio1, dev, 439 "reading extended partition table: error", 440 LOG_PRINTF, 0); 441 kprintf("\n"); 442 goto done; 443 } 444 445 /* Weakly verify it. */ 446 cp = bp->b_data; 447 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { 448 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART, 449 partname); 450 if (bootverbose) 451 kprintf("%s: invalid extended partition table: no magic\n", 452 sname); 453 goto done; 454 } 455 456 /* Make a copy of the partition table to avoid alignment problems. */ 457 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy)); 458 459 slice = ssp->dss_nslices; 460 for (dospart = 0, dp = &dpcopy[0]; dospart < NDOSPART; 461 dospart++, dp++) { 462 ext_sizes[dospart] = 0; 463 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 464 && dp->dp_start == 0 && dp->dp_size == 0) 465 continue; 466 if (dp->dp_typ == DOSPTYP_EXTENDED || 467 dp->dp_typ == DOSPTYP_EXTENDEDX) { 468 static char buf[32]; 469 470 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, 471 WHOLE_SLICE_PART, partname); 472 ksnprintf(buf, sizeof(buf), "%s", sname); 473 if (strlen(buf) < sizeof buf - 11) 474 strcat(buf, "<extended>"); 475 check_part(buf, dp, base_ext_offset, nsectors, 476 ntracks, mbr_offset); 477 ext_offsets[dospart] = base_ext_offset + dp->dp_start; 478 ext_sizes[dospart] = dp->dp_size; 479 } else { 480 sname = dsname(dev, dkunit(dev), slice, WHOLE_SLICE_PART, 481 partname); 482 check_part(sname, dp, ext_offset, nsectors, ntracks, 483 mbr_offset); 484 if (slice >= MAX_SLICES) { 485 kprintf("%s: too many slices\n", sname); 486 slice++; 487 continue; 488 } 489 sp = &ssp->dss_slices[slice]; 490 if (mbr_setslice(sname, info, sp, dp, ext_offset) != 0) 491 continue; 492 slice++; 493 } 494 } 495 ssp->dss_nslices = slice; 496 497 /* If we found any more slices, recursively find all the subslices. */ 498 for (dospart = 0; dospart < NDOSPART; dospart++) { 499 if (ext_sizes[dospart] != 0) { 500 mbr_extended(dev, info, ssp, ext_offsets[dospart], 501 ext_sizes[dospart], base_ext_offset, 502 nsectors, ntracks, mbr_offset, ++level); 503 } 504 } 505 506 done: 507 bp->b_flags |= B_INVAL | B_AGE; 508 brelse(bp); 509 } 510 511 static int 512 mbr_setslice(char *sname, struct disk_info *info, struct diskslice *sp, 513 struct dos_partition *dp, u_int64_t br_offset) 514 { 515 u_int64_t offset; 516 u_int64_t size; 517 518 offset = br_offset + dp->dp_start; 519 if (offset > info->d_media_blocks || offset < br_offset) { 520 kprintf( 521 "%s: slice starts beyond end of the disk: rejecting it\n", 522 sname); 523 return (1); 524 } 525 size = info->d_media_blocks - offset; 526 if (size >= dp->dp_size) { 527 if (dp->dp_size == 0xFFFFFFFFU) { 528 kprintf("%s: slice >2TB, using media size instead " 529 "of slice table size\n", sname); 530 } else { 531 size = dp->dp_size; 532 } 533 } else { 534 kprintf("%s: slice extends beyond end of disk: " 535 "truncating from %u to %llu sectors\n", 536 sname, dp->dp_size, (unsigned long long)size); 537 } 538 sp->ds_offset = offset; 539 sp->ds_size = size; 540 sp->ds_type = dp->dp_typ; 541 bzero(&sp->ds_type_uuid, sizeof(sp->ds_type_uuid)); 542 bzero(&sp->ds_stor_uuid, sizeof(sp->ds_type_uuid)); 543 544 /* 545 * Slices do not overlap with the parent (if any). 546 */ 547 sp->ds_reserved = 0; 548 return (0); 549 } 550