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. 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.
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
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 $
42 #include <sys/param.h>
43 #include <sys/systm.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>
53 #include <sys/malloc.h>
54 #include <sys/syslog.h>
55 #include <sys/device.h>
57 #define TRACE(str) do { if (dsi_debug) kprintf str; } while (0)
59 static volatile u_char dsi_debug;
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.
69 * We still have to recognize the old table though, even though we stopped
70 * inflicting it upon the world.
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, },
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, },
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,
93 static int mbr_setslice (char *sname, struct disk_info *info,
94 struct diskslice *sp, struct dos_partition *dp,
99 mbrinit(cdev_t dev, struct disk_info *info, struct diskslices **sspp)
104 struct dos_partition *dp;
105 struct dos_partition *dp0;
106 struct dos_partition dpcopy[NDOSPART];
111 u_int64_t mbr_offset;
114 char *sname = "tempname";
115 struct diskslice *sp;
116 struct diskslices *ssp;
119 mbr_offset = DOSBBSECTOR;
121 if (info->d_media_blksize & DEV_BMASK)
123 /* Read master boot record. */
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",
141 /* Weakly verify it. */
143 //sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART, partname);
144 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) {
146 kprintf("%s: invalid primary partition table: no magic\n",
152 /* Make a copy of the partition table to avoid alignment problems. */
153 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy));
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
162 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) {
164 (dp->dp_typ == DOSPTYP_PMBR || dp->dp_typ == DOSPTYP_GPT)) {
167 "%s: Found GPT in slice #%d\n", sname, dospart + 1);
168 error = gptinit(dev, info, sspp);
172 if (dp->dp_typ == DOSPTYP_ONTRACK) {
175 "%s: Found \"Ontrack Disk Manager\" on this disk.\n", sname);
176 bp->b_flags |= B_INVAL | B_AGE;
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) {
188 TRACE(("%s: invalid primary partition table: historical\n",
193 "%s: invalid primary partition table: Dangerously Dedicated (ignored)\n",
199 /* Guess the geometry. */
202 * Perhaps skip entries with 0 size.
203 * Perhaps only look at entries of type DOSPTYP_386BSD.
208 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) {
213 ncyls = DPCYL(dp->dp_ecyl, dp->dp_esect) + 1;
214 if (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;
225 * Check that we have guessed the geometry right by checking the
231 * Check for overlaps.
232 * Check against d_secperunit if the latter is reliable.
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)
239 //sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart,
240 // WHOLE_SLICE_PART, partname);
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.
249 check_part(sname, dp, mbr_offset, max_nsectors, max_ntracks,
256 * Accept the DOS partition table.
258 * Adjust the disk information structure with updated CHS
259 * conversion parameters, but only use values extracted from
260 * the primary partition table.
262 * NOTE! Regardless of our having to deal with this old cruft,
263 * we do not screw around with the info->d_media* parameters.
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;
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
280 kfree(*sspp, M_DEVBUF);
281 ssp = dsmakeslicestruct(MAX_SLICES, info);
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);
291 ssp->dss_nslices = BASE_SLICE + NDOSPART;
293 /* Handle extended partitions. */
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);
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.
309 if (ssp->dss_nslices > MAX_SLICES)
310 ssp->dss_nslices = MAX_SLICES;
313 bp->b_flags |= B_INVAL | B_AGE;
321 check_part(char *sname, struct dos_partition *dp, u_int64_t offset,
322 int nsectors, int ntracks, u_int64_t mbr_offset)
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
340 ssector1 = offset + dp->dp_start;
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.
349 if ((ssector < ssector1
350 && ((chs_ssect == nsectors && dp->dp_shd == ntracks - 1
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));
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
366 esector1 = ssector1 + dp->dp_size - 1;
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.
374 if ((esector < esector1
375 && ((chs_esect == nsectors && dp->dp_ehd == ntracks - 1
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));
387 error = (ssector == ssector1 && esector == esector1) ? 0 : EINVAL;
389 kprintf("%s: type 0x%x, start %llu, end = %llu, size %u %s\n",
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);
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)
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];
420 struct diskslice *sp;
424 "%s: excessive recursion in search for slices; aborting search\n",
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",
445 /* Weakly verify it. */
447 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) {
448 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART,
451 kprintf("%s: invalid extended partition table: no magic\n",
456 /* Make a copy of the partition table to avoid alignment problems. */
457 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy));
459 slice = ssp->dss_nslices;
460 for (dospart = 0, dp = &dpcopy[0]; dospart < NDOSPART;
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)
466 if (dp->dp_typ == DOSPTYP_EXTENDED ||
467 dp->dp_typ == DOSPTYP_EXTENDEDX) {
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;
480 sname = dsname(dev, dkunit(dev), slice, WHOLE_SLICE_PART,
482 check_part(sname, dp, ext_offset, nsectors, ntracks,
484 if (slice >= MAX_SLICES) {
485 kprintf("%s: too many slices\n", sname);
489 sp = &ssp->dss_slices[slice];
490 if (mbr_setslice(sname, info, sp, dp, ext_offset) != 0)
495 ssp->dss_nslices = slice;
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);
507 bp->b_flags |= B_INVAL | B_AGE;
512 mbr_setslice(char *sname, struct disk_info *info, struct diskslice *sp,
513 struct dos_partition *dp, u_int64_t br_offset)
518 offset = br_offset + dp->dp_start;
519 if (offset > info->d_media_blocks || offset < br_offset) {
521 "%s: slice starts beyond end of the disk: rejecting it\n",
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);
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);
538 sp->ds_offset = offset;
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));
545 * Slices do not overlap with the parent (if any).