2 * Copyright (c) 1994 Bruce D. Evans.
5 * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * from: @(#)ufs_disksubr.c 7.16 (Berkeley) 5/4/91
33 * from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $
34 * $FreeBSD: src/sys/kern/subr_diskmbr.c,v 1.45 2000/01/28 10:22:07 bde Exp $
37 #include <sys/param.h>
38 #include <sys/systm.h>
41 #include <sys/diskslice.h>
42 #define DOSPTYP_EXTENDED 5
43 #define DOSPTYP_EXTENDEDX 15
44 #define DOSPTYP_ONTRACK 84
45 #include <sys/diskmbr.h>
47 #include <sys/malloc.h>
48 #include <sys/syslog.h>
49 #include <sys/device.h>
51 #define TRACE(str) do { if (dsi_debug) kprintf str; } while (0)
53 static volatile u_char dsi_debug;
56 * This is what we have embedded in every boot1 for supporting the bogus
57 * "Dangerously Dedicated" mode. However, the old table is broken because
58 * it has an illegal geometry in it - it specifies 256 heads (heads = end
59 * head + 1) which causes nasty stuff when that wraps to zero in bios code.
60 * eg: divide by zero etc. This caused the dead-thinkpad problem, numerous
61 * SCSI bios crashes, EFI to crash, etc.
63 * We still have to recognize the old table though, even though we stopped
64 * inflicting it upon the world.
66 static struct dos_partition historical_bogus_partition_table[NDOSPART] = {
67 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
68 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
69 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
70 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 255, 255, 255, 0, 50000, },
72 static struct dos_partition historical_bogus_partition_table_fixed[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, 254, 255, 255, 0, 50000, },
79 static int check_part (char *sname, struct dos_partition *dp,
80 u_int64_t offset, int nsectors, int ntracks,
81 u_int64_t mbr_offset);
82 static void mbr_extended (cdev_t dev, struct disk_info *info,
83 struct diskslices *ssp, u_int64_t ext_offset,
84 u_int64_t ext_size, u_int64_t base_ext_offset,
85 int nsectors, int ntracks, u_int64_t mbr_offset,
87 static int mbr_setslice (char *sname, struct disk_info *info,
88 struct diskslice *sp, struct dos_partition *dp,
93 mbrinit(cdev_t dev, struct disk_info *info, struct diskslices **sspp)
98 struct dos_partition *dp;
99 struct dos_partition *dp0;
100 struct dos_partition dpcopy[NDOSPART];
105 u_int64_t mbr_offset;
108 char *sname = "tempname";
109 struct diskslice *sp;
110 struct diskslices *ssp;
113 mbr_offset = DOSBBSECTOR;
116 * Don't bother if the block size is weird or the
117 * media size is 0 (probably means no media present).
119 if (info->d_media_blksize & DEV_BMASK)
121 if (info->d_media_size == 0)
125 * Read master boot record.
128 bp = geteblk((int)info->d_media_blksize);
129 bp->b_bio1.bio_offset = (off_t)mbr_offset * info->d_media_blksize;
130 bp->b_bio1.bio_done = biodone_sync;
131 bp->b_bio1.bio_flags |= BIO_SYNC;
132 bp->b_bcount = info->d_media_blksize;
133 bp->b_cmd = BUF_CMD_READ;
134 dev_dstrategy(wdev, &bp->b_bio1);
135 if (biowait(&bp->b_bio1, "mbrrd") != 0) {
136 if ((info->d_dsflags & DSO_MBRQUIET) == 0) {
137 diskerr(&bp->b_bio1, wdev,
138 "reading primary partition table: error",
146 /* Weakly verify it. */
148 sname = dsname(dev, 0, 0, 0, NULL);
149 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) {
151 kprintf("%s: invalid primary partition table: no magic\n",
157 /* Make a copy of the partition table to avoid alignment problems. */
158 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy));
163 * Check for "Ontrack Diskmanager" or GPT. If a GPT is found in
164 * the first dos partition, ignore the rest of the MBR and go
167 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) {
169 (dp->dp_typ == DOSPTYP_PMBR || dp->dp_typ == DOSPTYP_GPT)) {
172 "%s: Found GPT in slice #%d\n", sname, dospart + 1);
173 error = gptinit(dev, info, sspp);
177 if (dp->dp_typ == DOSPTYP_ONTRACK) {
180 "%s: Found \"Ontrack Disk Manager\" on this disk.\n", sname);
181 bp->b_flags |= B_INVAL | B_AGE;
188 if (bcmp(dp0, historical_bogus_partition_table,
189 sizeof historical_bogus_partition_table) == 0 ||
190 bcmp(dp0, historical_bogus_partition_table_fixed,
191 sizeof historical_bogus_partition_table_fixed) == 0) {
193 TRACE(("%s: invalid primary partition table: historical\n",
198 "%s: invalid primary partition table: Dangerously Dedicated (ignored)\n",
204 /* Guess the geometry. */
207 * Perhaps skip entries with 0 size.
208 * Perhaps only look at entries of type DOSPTYP_386BSD.
213 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) {
218 ncyls = DPCYL(dp->dp_ecyl, dp->dp_esect) + 1;
219 if (max_ncyls < ncyls)
221 nsectors = DPSECT(dp->dp_esect);
222 if (max_nsectors < nsectors)
223 max_nsectors = nsectors;
224 ntracks = dp->dp_ehd + 1;
225 if (max_ntracks < ntracks)
226 max_ntracks = ntracks;
230 * Check that we have guessed the geometry right by checking the
236 * Check for overlaps.
237 * Check against d_secperunit if the latter is reliable.
240 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) {
241 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0
242 && dp->dp_start == 0 && dp->dp_size == 0)
244 //sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart,
245 // WHOLE_SLICE_PART, partname);
248 * Temporarily ignore errors from this check. We could
249 * simplify things by accepting the table eariler if we
250 * always ignore errors here. Perhaps we should always
251 * accept the table if the magic is right but not let
252 * bad entries affect the geometry.
254 check_part(sname, dp, mbr_offset, max_nsectors, max_ntracks,
261 * Accept the DOS partition table.
263 * Adjust the disk information structure with updated CHS
264 * conversion parameters, but only use values extracted from
265 * the primary partition table.
267 * NOTE! Regardless of our having to deal with this old cruft,
268 * we do not screw around with the info->d_media* parameters.
270 secpercyl = (u_long)max_nsectors * max_ntracks;
271 if (secpercyl != 0 && mbr_offset == DOSBBSECTOR) {
272 info->d_secpertrack = max_nsectors;
273 info->d_nheads = max_ntracks;
274 info->d_secpercyl = secpercyl;
275 info->d_ncylinders = info->d_media_blocks / secpercyl;
279 * We are passed a pointer to a suitably initialized minimal
280 * slices "struct" with no dangling pointers in it. Replace it
281 * by a maximal one. This usually oversizes the "struct", but
282 * enlarging it while searching for logical drives would be
285 kfree(*sspp, M_DEVBUF);
286 ssp = dsmakeslicestruct(MAX_SLICES, info);
289 /* Initialize normal slices. */
290 sp = &ssp->dss_slices[BASE_SLICE];
291 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) {
292 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart,
293 WHOLE_SLICE_PART, partname);
294 (void)mbr_setslice(sname, info, sp, dp, mbr_offset);
296 ssp->dss_nslices = BASE_SLICE + NDOSPART;
298 /* Handle extended partitions. */
300 for (dospart = 0; dospart < NDOSPART; dospart++, sp++) {
301 if (sp->ds_type == DOSPTYP_EXTENDED ||
302 sp->ds_type == DOSPTYP_EXTENDEDX) {
303 mbr_extended(wdev, info, ssp,
304 sp->ds_offset, sp->ds_size, sp->ds_offset,
305 max_nsectors, max_ntracks, mbr_offset, 1);
310 * mbr_extended() abuses ssp->dss_nslices for the number of slices
311 * that would be found if there were no limit on the number of slices
312 * in *ssp. Cut it back now.
314 if (ssp->dss_nslices > MAX_SLICES)
315 ssp->dss_nslices = MAX_SLICES;
318 bp->b_flags |= B_INVAL | B_AGE;
326 check_part(char *sname, struct dos_partition *dp, u_int64_t offset,
327 int nsectors, int ntracks, u_int64_t mbr_offset)
340 secpercyl = (u_long)nsectors * ntracks;
341 chs_scyl = DPCYL(dp->dp_scyl, dp->dp_ssect);
342 chs_ssect = DPSECT(dp->dp_ssect);
343 ssector = chs_ssect - 1 + dp->dp_shd * nsectors + chs_scyl * secpercyl
345 ssector1 = offset + dp->dp_start;
348 * If ssector1 is on a cylinder >= 1024, then ssector can't be right.
349 * Allow the C/H/S for it to be 1023/ntracks-1/nsectors, or correct
350 * apart from the cylinder being reduced modulo 1024. Always allow
351 * 1023/255/63, because this is the official way to represent
352 * pure-LBA for the starting position.
354 if ((ssector < ssector1
355 && ((chs_ssect == nsectors && dp->dp_shd == ntracks - 1
358 && (ssector1 - ssector) % (1024 * secpercyl) == 0)))
359 || (dp->dp_scyl == 255 && dp->dp_shd == 255
360 && dp->dp_ssect == 255)) {
361 TRACE(("%s: C/H/S start %d/%d/%d, start %llu: allow\n",
362 sname, chs_scyl, dp->dp_shd, chs_ssect,
363 (long long)ssector1));
367 chs_ecyl = DPCYL(dp->dp_ecyl, dp->dp_esect);
368 chs_esect = DPSECT(dp->dp_esect);
369 esector = chs_esect - 1 + dp->dp_ehd * nsectors + chs_ecyl * secpercyl
371 esector1 = ssector1 + dp->dp_size - 1;
374 * Allow certain bogus C/H/S values for esector, as above. However,
375 * heads == 255 isn't really legal and causes some BIOS crashes. The
376 * correct value to indicate a pure-LBA end is 1023/heads-1/sectors -
377 * usually 1023/254/63. "heads" is base 0, "sectors" is base 1.
379 if ((esector < esector1
380 && ((chs_esect == nsectors && dp->dp_ehd == ntracks - 1
383 && (esector1 - esector) % (1024 * secpercyl) == 0)))
384 || (dp->dp_ecyl == 255 && dp->dp_ehd == 255
385 && dp->dp_esect == 255)) {
386 TRACE(("%s: C/H/S end %d/%d/%d, end %llu: allow\n",
387 sname, chs_ecyl, dp->dp_ehd, chs_esect,
388 (long long)esector1));
392 error = (ssector == ssector1 && esector == esector1) ? 0 : EINVAL;
394 kprintf("%s: type 0x%x, start %llu, end = %llu, size %u %s\n",
396 (long long)ssector1, (long long)esector1,
397 dp->dp_size, (error ? "" : ": OK"));
398 if (ssector != ssector1 && bootverbose)
399 kprintf("%s: C/H/S start %d/%d/%d (%llu) != start %llu: invalid\n",
400 sname, chs_scyl, dp->dp_shd, chs_ssect,
401 (long long)ssector, (long long)ssector1);
402 if (esector != esector1 && bootverbose)
403 kprintf("%s: C/H/S end %d/%d/%d (%llu) != end %llu: invalid\n",
404 sname, chs_ecyl, dp->dp_ehd, chs_esect,
405 (long long)esector, (long long)esector1);
411 mbr_extended(cdev_t dev, struct disk_info *info, struct diskslices *ssp,
412 u_int64_t ext_offset, u_int64_t ext_size, u_int64_t base_ext_offset,
413 int nsectors, int ntracks, u_int64_t mbr_offset, int level)
418 struct dos_partition *dp;
419 struct dos_partition dpcopy[NDOSPART];
420 u_int64_t ext_offsets[NDOSPART];
421 u_int64_t ext_sizes[NDOSPART];
425 struct diskslice *sp;
429 "%s: excessive recursion in search for slices; aborting search\n",
434 /* Read extended boot record. */
435 bp = geteblk((int)info->d_media_blksize);
436 bp->b_bio1.bio_offset = (off_t)ext_offset * info->d_media_blksize;
437 bp->b_bio1.bio_done = biodone_sync;
438 bp->b_bio1.bio_flags |= BIO_SYNC;
439 bp->b_bcount = info->d_media_blksize;
440 bp->b_cmd = BUF_CMD_READ;
441 dev_dstrategy(dev, &bp->b_bio1);
442 if (biowait(&bp->b_bio1, "mbrrd") != 0) {
443 diskerr(&bp->b_bio1, dev,
444 "reading extended partition table: error",
450 /* Weakly verify it. */
452 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) {
453 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART,
456 kprintf("%s: invalid extended partition table: no magic\n",
461 /* Make a copy of the partition table to avoid alignment problems. */
462 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy));
464 slice = ssp->dss_nslices;
465 for (dospart = 0, dp = &dpcopy[0]; dospart < NDOSPART;
467 ext_sizes[dospart] = 0;
468 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0
469 && dp->dp_start == 0 && dp->dp_size == 0)
471 if (dp->dp_typ == DOSPTYP_EXTENDED ||
472 dp->dp_typ == DOSPTYP_EXTENDEDX) {
475 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE,
476 WHOLE_SLICE_PART, partname);
477 ksnprintf(buf, sizeof(buf), "%s", sname);
478 if (strlen(buf) < sizeof buf - 11)
479 strcat(buf, "<extended>");
480 check_part(buf, dp, base_ext_offset, nsectors,
481 ntracks, mbr_offset);
482 ext_offsets[dospart] = base_ext_offset + dp->dp_start;
483 ext_sizes[dospart] = dp->dp_size;
485 sname = dsname(dev, dkunit(dev), slice, WHOLE_SLICE_PART,
487 check_part(sname, dp, ext_offset, nsectors, ntracks,
489 if (slice >= MAX_SLICES) {
490 kprintf("%s: too many slices\n", sname);
494 sp = &ssp->dss_slices[slice];
495 if (mbr_setslice(sname, info, sp, dp, ext_offset) != 0)
500 ssp->dss_nslices = slice;
502 /* If we found any more slices, recursively find all the subslices. */
503 for (dospart = 0; dospart < NDOSPART; dospart++) {
504 if (ext_sizes[dospart] != 0) {
505 mbr_extended(dev, info, ssp, ext_offsets[dospart],
506 ext_sizes[dospart], base_ext_offset,
507 nsectors, ntracks, mbr_offset, ++level);
512 bp->b_flags |= B_INVAL | B_AGE;
517 mbr_setslice(char *sname, struct disk_info *info, struct diskslice *sp,
518 struct dos_partition *dp, u_int64_t br_offset)
523 offset = br_offset + dp->dp_start;
524 if (offset > info->d_media_blocks || offset < br_offset) {
526 "%s: slice starts beyond end of the disk: rejecting it\n",
530 size = info->d_media_blocks - offset;
531 if (size >= dp->dp_size) {
532 if (dp->dp_size == 0xFFFFFFFFU) {
533 kprintf("%s: slice >2TB, using media size instead "
534 "of slice table size\n", sname);
539 kprintf("%s: slice extends beyond end of disk: "
540 "truncating from %u to %llu sectors\n",
541 sname, dp->dp_size, (unsigned long long)size);
543 sp->ds_offset = offset;
545 sp->ds_type = dp->dp_typ;
546 bzero(&sp->ds_type_uuid, sizeof(sp->ds_type_uuid));
547 bzero(&sp->ds_stor_uuid, sizeof(sp->ds_type_uuid));
550 * Slices do not overlap with the parent (if any).