sys/kern/subr_diskmbr.c

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