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 */ 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/buf.h> 44 #include <sys/conf.h> 45 #include <sys/diskslice.h> 46 #define DOSPTYP_EXTENDED 5 47 #define DOSPTYP_EXTENDEDX 15 48 #define DOSPTYP_ONTRACK 84 49 #include <sys/diskmbr.h> 50 #include <sys/disk.h> 51 #include <sys/malloc.h> 52 #include <sys/syslog.h> 53 #include <sys/device.h> 54 55 #define TRACE(str) do { if (dsi_debug) kprintf str; } while (0) 56 57 static volatile u_char dsi_debug; 58 59 /* 60 * This is what we have embedded in every boot1 for supporting the bogus 61 * "Dangerously Dedicated" mode. However, the old table is broken because 62 * it has an illegal geometry in it - it specifies 256 heads (heads = end 63 * head + 1) which causes nasty stuff when that wraps to zero in bios code. 64 * eg: divide by zero etc. This caused the dead-thinkpad problem, numerous 65 * SCSI bios crashes, EFI to crash, etc. 66 * 67 * We still have to recognize the old table though, even though we stopped 68 * inflicting it upon the world. 69 */ 70 static struct dos_partition historical_bogus_partition_table[NDOSPART] = { 71 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 72 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 73 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 74 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 255, 255, 255, 0, 50000, }, 75 }; 76 static struct dos_partition historical_bogus_partition_table_fixed[NDOSPART] = { 77 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 78 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 79 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 80 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 254, 255, 255, 0, 50000, }, 81 }; 82 83 static int check_part (char *sname, struct dos_partition *dp, 84 u_int64_t offset, int nsectors, int ntracks, 85 u_int64_t mbr_offset); 86 static void mbr_extended (cdev_t dev, struct disk_info *info, 87 struct diskslices *ssp, u_int64_t ext_offset, 88 u_int64_t ext_size, u_int64_t base_ext_offset, 89 int nsectors, int ntracks, u_int64_t mbr_offset, 90 int level); 91 static int mbr_setslice (char *sname, struct disk_info *info, 92 struct diskslice *sp, struct dos_partition *dp, 93 u_int64_t br_offset); 94 95 96 int 97 mbrinit(cdev_t dev, struct disk_info *info, struct diskslices **sspp) 98 { 99 struct buf *bp; 100 u_char *cp; 101 int dospart; 102 struct dos_partition *dp; 103 struct dos_partition *dp0; 104 struct dos_partition dpcopy[NDOSPART]; 105 int error; 106 int max_ncyls; 107 int max_nsectors; 108 int max_ntracks; 109 u_int64_t mbr_offset; 110 char partname[2]; 111 u_long secpercyl; 112 char *sname = "tempname"; 113 struct diskslice *sp; 114 struct diskslices *ssp; 115 cdev_t wdev; 116 117 mbr_offset = DOSBBSECTOR; 118 reread_mbr: 119 /* 120 * Don't bother if the block size is weird or the 121 * media size is 0 (probably means no media present). 122 */ 123 if (info->d_media_blksize & DEV_BMASK) 124 return (EIO); 125 if (info->d_media_size == 0) 126 return (EIO); 127 128 /* 129 * Read master boot record. 130 */ 131 wdev = dev; 132 bp = geteblk((int)info->d_media_blksize); 133 bp->b_bio1.bio_offset = (off_t)mbr_offset * info->d_media_blksize; 134 bp->b_bio1.bio_done = biodone_sync; 135 bp->b_bio1.bio_flags |= BIO_SYNC; 136 bp->b_bcount = info->d_media_blksize; 137 bp->b_cmd = BUF_CMD_READ; 138 dev_dstrategy(wdev, &bp->b_bio1); 139 if (biowait(&bp->b_bio1, "mbrrd") != 0) { 140 if ((info->d_dsflags & DSO_MBRQUIET) == 0) { 141 diskerr(&bp->b_bio1, wdev, 142 "reading primary partition table: error", 143 LOG_PRINTF, 0); 144 kprintf("\n"); 145 } 146 error = EIO; 147 goto done; 148 } 149 150 /* Weakly verify it. */ 151 cp = bp->b_data; 152 sname = dsname(dev, 0, 0, 0, NULL); 153 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { 154 if (bootverbose) 155 kprintf("%s: invalid primary partition table: no magic\n", 156 sname); 157 error = EINVAL; 158 goto done; 159 } 160 161 /* Make a copy of the partition table to avoid alignment problems. */ 162 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy)); 163 164 dp0 = &dpcopy[0]; 165 166 /* 167 * Check for "Ontrack Diskmanager" or GPT. If a GPT is found in 168 * the first dos partition, ignore the rest of the MBR and go 169 * to GPT processing. 170 */ 171 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 172 if (dospart == 0 && 173 (dp->dp_typ == DOSPTYP_PMBR || dp->dp_typ == DOSPTYP_GPT)) { 174 if (bootverbose) 175 kprintf( 176 "%s: Found GPT in slice #%d\n", sname, dospart + 1); 177 error = gptinit(dev, info, sspp); 178 goto done; 179 } 180 181 if (dp->dp_typ == DOSPTYP_ONTRACK) { 182 if (bootverbose) 183 kprintf( 184 "%s: Found \"Ontrack Disk Manager\" on this disk.\n", sname); 185 bp->b_flags |= B_INVAL | B_AGE; 186 brelse(bp); 187 mbr_offset = 63; 188 goto reread_mbr; 189 } 190 } 191 192 if (bcmp(dp0, historical_bogus_partition_table, 193 sizeof historical_bogus_partition_table) == 0 || 194 bcmp(dp0, historical_bogus_partition_table_fixed, 195 sizeof historical_bogus_partition_table_fixed) == 0) { 196 #if 0 197 TRACE(("%s: invalid primary partition table: historical\n", 198 sname)); 199 #endif /* 0 */ 200 if (bootverbose) 201 kprintf( 202 "%s: invalid primary partition table: Dangerously Dedicated (ignored)\n", 203 sname); 204 error = EINVAL; 205 goto done; 206 } 207 208 /* Guess the geometry. */ 209 /* 210 * TODO: 211 * Perhaps skip entries with 0 size. 212 * Perhaps only look at entries of type DOSPTYP_386BSD. 213 */ 214 max_ncyls = 0; 215 max_nsectors = 0; 216 max_ntracks = 0; 217 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 218 int ncyls; 219 int nsectors; 220 int ntracks; 221 222 ncyls = DPCYL(dp->dp_ecyl, dp->dp_esect) + 1; 223 if (max_ncyls < ncyls) 224 max_ncyls = ncyls; 225 nsectors = DPSECT(dp->dp_esect); 226 if (max_nsectors < nsectors) 227 max_nsectors = nsectors; 228 ntracks = dp->dp_ehd + 1; 229 if (max_ntracks < ntracks) 230 max_ntracks = ntracks; 231 } 232 233 /* 234 * Check that we have guessed the geometry right by checking the 235 * partition entries. 236 */ 237 /* 238 * TODO: 239 * As above. 240 * Check for overlaps. 241 * Check against d_secperunit if the latter is reliable. 242 */ 243 error = 0; 244 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 245 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 246 && dp->dp_start == 0 && dp->dp_size == 0) 247 continue; 248 //sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart, 249 // WHOLE_SLICE_PART, partname); 250 251 /* 252 * Temporarily ignore errors from this check. We could 253 * simplify things by accepting the table eariler if we 254 * always ignore errors here. Perhaps we should always 255 * accept the table if the magic is right but not let 256 * bad entries affect the geometry. 257 */ 258 check_part(sname, dp, mbr_offset, max_nsectors, max_ntracks, 259 mbr_offset); 260 } 261 if (error != 0) 262 goto done; 263 264 /* 265 * Accept the DOS partition table. 266 * 267 * Adjust the disk information structure with updated CHS 268 * conversion parameters, but only use values extracted from 269 * the primary partition table. 270 * 271 * NOTE! Regardless of our having to deal with this old cruft, 272 * we do not screw around with the info->d_media* parameters. 273 */ 274 secpercyl = (u_long)max_nsectors * max_ntracks; 275 if (secpercyl != 0 && mbr_offset == DOSBBSECTOR) { 276 info->d_secpertrack = max_nsectors; 277 info->d_nheads = max_ntracks; 278 info->d_secpercyl = secpercyl; 279 info->d_ncylinders = info->d_media_blocks / secpercyl; 280 } 281 282 /* 283 * We are passed a pointer to a suitably initialized minimal 284 * slices "struct" with no dangling pointers in it. Replace it 285 * by a maximal one. This usually oversizes the "struct", but 286 * enlarging it while searching for logical drives would be 287 * inconvenient. 288 */ 289 kfree(*sspp, M_DEVBUF); 290 ssp = dsmakeslicestruct(MAX_SLICES, info); 291 *sspp = ssp; 292 293 /* Initialize normal slices. */ 294 sp = &ssp->dss_slices[BASE_SLICE]; 295 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) { 296 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart, 297 WHOLE_SLICE_PART, partname); 298 (void)mbr_setslice(sname, info, sp, dp, mbr_offset); 299 } 300 ssp->dss_nslices = BASE_SLICE + NDOSPART; 301 302 /* Handle extended partitions. */ 303 sp -= NDOSPART; 304 for (dospart = 0; dospart < NDOSPART; dospart++, sp++) { 305 if (sp->ds_type == DOSPTYP_EXTENDED || 306 sp->ds_type == DOSPTYP_EXTENDEDX) { 307 mbr_extended(wdev, info, ssp, 308 sp->ds_offset, sp->ds_size, sp->ds_offset, 309 max_nsectors, max_ntracks, mbr_offset, 1); 310 } 311 } 312 313 /* 314 * mbr_extended() abuses ssp->dss_nslices for the number of slices 315 * that would be found if there were no limit on the number of slices 316 * in *ssp. Cut it back now. 317 */ 318 if (ssp->dss_nslices > MAX_SLICES) 319 ssp->dss_nslices = MAX_SLICES; 320 321 done: 322 bp->b_flags |= B_INVAL | B_AGE; 323 brelse(bp); 324 if (error == EINVAL) 325 error = 0; 326 return (error); 327 } 328 329 static int 330 check_part(char *sname, struct dos_partition *dp, u_int64_t offset, 331 int nsectors, int ntracks, u_int64_t mbr_offset) 332 { 333 int chs_ecyl; 334 int chs_esect; 335 int chs_scyl; 336 int chs_ssect; 337 int error; 338 u_long secpercyl; 339 u_int64_t esector; 340 u_int64_t esector1; 341 u_int64_t ssector; 342 u_int64_t ssector1; 343 344 secpercyl = (u_long)nsectors * ntracks; 345 chs_scyl = DPCYL(dp->dp_scyl, dp->dp_ssect); 346 chs_ssect = DPSECT(dp->dp_ssect); 347 ssector = chs_ssect - 1 + dp->dp_shd * nsectors + chs_scyl * secpercyl 348 + mbr_offset; 349 ssector1 = offset + dp->dp_start; 350 351 /* 352 * If ssector1 is on a cylinder >= 1024, then ssector can't be right. 353 * Allow the C/H/S for it to be 1023/ntracks-1/nsectors, or correct 354 * apart from the cylinder being reduced modulo 1024. Always allow 355 * 1023/255/63, because this is the official way to represent 356 * pure-LBA for the starting position. 357 */ 358 if ((ssector < ssector1 359 && ((chs_ssect == nsectors && dp->dp_shd == ntracks - 1 360 && chs_scyl == 1023) 361 || (secpercyl != 0 362 && (ssector1 - ssector) % (1024 * secpercyl) == 0))) 363 || (dp->dp_scyl == 255 && dp->dp_shd == 255 364 && dp->dp_ssect == 255)) { 365 TRACE(("%s: C/H/S start %d/%d/%d, start %llu: allow\n", 366 sname, chs_scyl, dp->dp_shd, chs_ssect, 367 (long long)ssector1)); 368 ssector = ssector1; 369 } 370 371 chs_ecyl = DPCYL(dp->dp_ecyl, dp->dp_esect); 372 chs_esect = DPSECT(dp->dp_esect); 373 esector = chs_esect - 1 + dp->dp_ehd * nsectors + chs_ecyl * secpercyl 374 + mbr_offset; 375 esector1 = ssector1 + dp->dp_size - 1; 376 377 /* 378 * Allow certain bogus C/H/S values for esector, as above. However, 379 * heads == 255 isn't really legal and causes some BIOS crashes. The 380 * correct value to indicate a pure-LBA end is 1023/heads-1/sectors - 381 * usually 1023/254/63. "heads" is base 0, "sectors" is base 1. 382 */ 383 if ((esector < esector1 384 && ((chs_esect == nsectors && dp->dp_ehd == ntracks - 1 385 && chs_ecyl == 1023) 386 || (secpercyl != 0 387 && (esector1 - esector) % (1024 * secpercyl) == 0))) 388 || (dp->dp_ecyl == 255 && dp->dp_ehd == 255 389 && dp->dp_esect == 255)) { 390 TRACE(("%s: C/H/S end %d/%d/%d, end %llu: allow\n", 391 sname, chs_ecyl, dp->dp_ehd, chs_esect, 392 (long long)esector1)); 393 esector = esector1; 394 } 395 396 error = (ssector == ssector1 && esector == esector1) ? 0 : EINVAL; 397 if (bootverbose) 398 kprintf("%s: type 0x%x, start %llu, end = %llu, size %u %s\n", 399 sname, dp->dp_typ, 400 (long long)ssector1, (long long)esector1, 401 dp->dp_size, (error ? "" : ": OK")); 402 if (ssector != ssector1 && bootverbose) 403 kprintf("%s: C/H/S start %d/%d/%d (%llu) != start %llu: invalid\n", 404 sname, chs_scyl, dp->dp_shd, chs_ssect, 405 (long long)ssector, (long long)ssector1); 406 if (esector != esector1 && bootverbose) 407 kprintf("%s: C/H/S end %d/%d/%d (%llu) != end %llu: invalid\n", 408 sname, chs_ecyl, dp->dp_ehd, chs_esect, 409 (long long)esector, (long long)esector1); 410 return (error); 411 } 412 413 static 414 void 415 mbr_extended(cdev_t dev, struct disk_info *info, struct diskslices *ssp, 416 u_int64_t ext_offset, u_int64_t ext_size, u_int64_t base_ext_offset, 417 int nsectors, int ntracks, u_int64_t mbr_offset, int level) 418 { 419 struct buf *bp; 420 u_char *cp; 421 int dospart; 422 struct dos_partition *dp; 423 struct dos_partition dpcopy[NDOSPART]; 424 u_int64_t ext_offsets[NDOSPART]; 425 u_int64_t ext_sizes[NDOSPART]; 426 char partname[2]; 427 int slice; 428 char *sname; 429 struct diskslice *sp; 430 431 if (level >= 16) { 432 kprintf( 433 "%s: excessive recursion in search for slices; aborting search\n", 434 devtoname(dev)); 435 return; 436 } 437 438 /* Read extended boot record. */ 439 bp = geteblk((int)info->d_media_blksize); 440 bp->b_bio1.bio_offset = (off_t)ext_offset * info->d_media_blksize; 441 bp->b_bio1.bio_done = biodone_sync; 442 bp->b_bio1.bio_flags |= BIO_SYNC; 443 bp->b_bcount = info->d_media_blksize; 444 bp->b_cmd = BUF_CMD_READ; 445 dev_dstrategy(dev, &bp->b_bio1); 446 if (biowait(&bp->b_bio1, "mbrrd") != 0) { 447 diskerr(&bp->b_bio1, dev, 448 "reading extended partition table: error", 449 LOG_PRINTF, 0); 450 kprintf("\n"); 451 goto done; 452 } 453 454 /* Weakly verify it. */ 455 cp = bp->b_data; 456 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { 457 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART, 458 partname); 459 if (bootverbose) 460 kprintf("%s: invalid extended partition table: no magic\n", 461 sname); 462 goto done; 463 } 464 465 /* Make a copy of the partition table to avoid alignment problems. */ 466 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy)); 467 468 slice = ssp->dss_nslices; 469 for (dospart = 0, dp = &dpcopy[0]; dospart < NDOSPART; 470 dospart++, dp++) { 471 ext_sizes[dospart] = 0; 472 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 473 && dp->dp_start == 0 && dp->dp_size == 0) 474 continue; 475 if (dp->dp_typ == DOSPTYP_EXTENDED || 476 dp->dp_typ == DOSPTYP_EXTENDEDX) { 477 static char buf[32]; 478 479 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, 480 WHOLE_SLICE_PART, partname); 481 ksnprintf(buf, sizeof(buf), "%s", sname); 482 if (strlen(buf) < sizeof buf - 11) 483 strcat(buf, "<extended>"); 484 check_part(buf, dp, base_ext_offset, nsectors, 485 ntracks, mbr_offset); 486 ext_offsets[dospart] = base_ext_offset + dp->dp_start; 487 ext_sizes[dospart] = dp->dp_size; 488 } else { 489 sname = dsname(dev, dkunit(dev), slice, WHOLE_SLICE_PART, 490 partname); 491 check_part(sname, dp, ext_offset, nsectors, ntracks, 492 mbr_offset); 493 if (slice >= MAX_SLICES) { 494 kprintf("%s: too many slices\n", sname); 495 slice++; 496 continue; 497 } 498 sp = &ssp->dss_slices[slice]; 499 if (mbr_setslice(sname, info, sp, dp, ext_offset) != 0) 500 continue; 501 slice++; 502 } 503 } 504 ssp->dss_nslices = slice; 505 506 /* If we found any more slices, recursively find all the subslices. */ 507 for (dospart = 0; dospart < NDOSPART; dospart++) { 508 if (ext_sizes[dospart] != 0) { 509 mbr_extended(dev, info, ssp, ext_offsets[dospart], 510 ext_sizes[dospart], base_ext_offset, 511 nsectors, ntracks, mbr_offset, ++level); 512 } 513 } 514 515 done: 516 bp->b_flags |= B_INVAL | B_AGE; 517 brelse(bp); 518 } 519 520 static int 521 mbr_setslice(char *sname, struct disk_info *info, struct diskslice *sp, 522 struct dos_partition *dp, u_int64_t br_offset) 523 { 524 u_int64_t offset; 525 u_int64_t size; 526 527 offset = br_offset + dp->dp_start; 528 if (offset > info->d_media_blocks || offset < br_offset) { 529 kprintf( 530 "%s: slice starts beyond end of the disk: rejecting it\n", 531 sname); 532 return (1); 533 } 534 size = info->d_media_blocks - offset; 535 if (size >= dp->dp_size) { 536 if (dp->dp_size == 0xFFFFFFFFU) { 537 kprintf("%s: slice >2TB, using media size instead " 538 "of slice table size\n", sname); 539 } else { 540 size = dp->dp_size; 541 } 542 } else { 543 kprintf("%s: slice extends beyond end of disk: " 544 "truncating from %u to %llu sectors\n", 545 sname, dp->dp_size, (unsigned long long)size); 546 } 547 sp->ds_offset = offset; 548 sp->ds_size = size; 549 sp->ds_type = dp->dp_typ; 550 bzero(&sp->ds_type_uuid, sizeof(sp->ds_type_uuid)); 551 bzero(&sp->ds_stor_uuid, sizeof(sp->ds_type_uuid)); 552 553 /* 554 * Slices do not overlap with the parent (if any). 555 */ 556 sp->ds_reserved = 0; 557 return (0); 558 } 559