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 1.13 2006/04/30 17:22:17 dillon Exp $
42 #include <sys/param.h>
43 #include <sys/systm.h>
46 #include <sys/disklabel.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/malloc.h>
53 #include <sys/syslog.h>
54 #include <sys/device.h>
56 #define TRACE(str) do { if (dsi_debug) printf str; } while (0)
58 static volatile u_char dsi_debug;
60 static struct dos_partition historical_bogus_partition_table[NDOSPART] = {
61 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
62 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
63 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
64 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 255, 255, 255, 0, 50000, },
67 static int check_part (char *sname, struct dos_partition *dp,
68 u_long offset, int nsectors, int ntracks,
70 static void mbr_extended (dev_t dev, struct disklabel *lp,
71 struct diskslices *ssp, u_long ext_offset,
72 u_long ext_size, u_long base_ext_offset,
73 int nsectors, int ntracks, u_long mbr_offset,
75 static int mbr_setslice (char *sname, struct disklabel *lp,
76 struct diskslice *sp, struct dos_partition *dp,
80 check_part(char *sname, struct dos_partition *dp, u_long offset,
81 int nsectors, int ntracks, u_long mbr_offset)
94 secpercyl = (u_long)nsectors * ntracks;
95 chs_scyl = DPCYL(dp->dp_scyl, dp->dp_ssect);
96 chs_ssect = DPSECT(dp->dp_ssect);
97 ssector = chs_ssect - 1 + dp->dp_shd * nsectors + chs_scyl * secpercyl
99 ssector1 = offset + dp->dp_start;
102 * If ssector1 is on a cylinder >= 1024, then ssector can't be right.
103 * Allow the C/H/S for it to be 1023/ntracks-1/nsectors, or correct
104 * apart from the cylinder being reduced modulo 1024. Always allow
107 if ((ssector < ssector1
108 && ((chs_ssect == nsectors && dp->dp_shd == ntracks - 1
111 && (ssector1 - ssector) % (1024 * secpercyl) == 0)))
112 || (dp->dp_scyl == 255 && dp->dp_shd == 255
113 && dp->dp_ssect == 255)) {
114 TRACE(("%s: C/H/S start %d/%d/%d, start %lu: allow\n",
115 sname, chs_scyl, dp->dp_shd, chs_ssect, ssector1));
119 chs_ecyl = DPCYL(dp->dp_ecyl, dp->dp_esect);
120 chs_esect = DPSECT(dp->dp_esect);
121 esector = chs_esect - 1 + dp->dp_ehd * nsectors + chs_ecyl * secpercyl
123 esector1 = ssector1 + dp->dp_size - 1;
125 /* Allow certain bogus C/H/S values for esector, as above. */
126 if ((esector < esector1
127 && ((chs_esect == nsectors && dp->dp_ehd == ntracks - 1
130 && (esector1 - esector) % (1024 * secpercyl) == 0)))
131 || (dp->dp_ecyl == 255 && dp->dp_ehd == 255
132 && dp->dp_esect == 255)) {
133 TRACE(("%s: C/H/S end %d/%d/%d, end %lu: allow\n",
134 sname, chs_ecyl, dp->dp_ehd, chs_esect, esector1));
138 error = (ssector == ssector1 && esector == esector1) ? 0 : EINVAL;
140 printf("%s: type 0x%x, start %lu, end = %lu, size %lu %s\n",
141 sname, dp->dp_typ, ssector1, esector1,
142 (u_long)dp->dp_size, error ? "" : ": OK");
143 if (ssector != ssector1 && bootverbose)
144 printf("%s: C/H/S start %d/%d/%d (%lu) != start %lu: invalid\n",
145 sname, chs_scyl, dp->dp_shd, chs_ssect,
147 if (esector != esector1 && bootverbose)
148 printf("%s: C/H/S end %d/%d/%d (%lu) != end %lu: invalid\n",
149 sname, chs_ecyl, dp->dp_ehd, chs_esect,
155 dsinit(dev_t dev, struct disklabel *lp, struct diskslices **sspp)
160 struct dos_partition *dp;
161 struct dos_partition *dp0;
162 struct dos_partition dpcopy[NDOSPART];
171 struct diskslice *sp;
172 struct diskslices *ssp;
175 mbr_offset = DOSBBSECTOR;
177 /* Read master boot record. */
178 wdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
179 bp = geteblk((int)lp->d_secsize);
180 bp->b_bio1.bio_offset = (off_t)mbr_offset * lp->d_secsize;
181 bp->b_bcount = lp->d_secsize;
182 bp->b_cmd = BUF_CMD_READ;
183 dev_dstrategy(wdev, &bp->b_bio1);
184 if (biowait(bp) != 0) {
185 diskerr(&bp->b_bio1, wdev,
186 "reading primary partition table: error",
187 LOG_PRINTF, 0, NULL);
193 /* Weakly verify it. */
195 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, RAW_PART, partname);
196 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) {
198 printf("%s: invalid primary partition table: no magic\n",
204 /* Make a copy of the partition table to avoid alignment problems. */
205 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy));
209 /* Check for "Ontrack Diskmanager". */
210 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) {
211 if (dp->dp_typ == DOSPTYP_ONTRACK) {
214 "%s: Found \"Ontrack Disk Manager\" on this disk.\n", sname);
215 bp->b_flags |= B_INVAL | B_AGE;
222 if (bcmp(dp0, historical_bogus_partition_table,
223 sizeof historical_bogus_partition_table) == 0) {
224 TRACE(("%s: invalid primary partition table: historical\n",
230 /* Guess the geometry. */
233 * Perhaps skip entries with 0 size.
234 * Perhaps only look at entries of type DOSPTYP_386BSD.
239 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) {
244 ncyls = DPCYL(dp->dp_ecyl, dp->dp_esect) + 1;
245 if (max_ncyls < ncyls)
247 nsectors = DPSECT(dp->dp_esect);
248 if (max_nsectors < nsectors)
249 max_nsectors = nsectors;
250 ntracks = dp->dp_ehd + 1;
251 if (max_ntracks < ntracks)
252 max_ntracks = ntracks;
256 * Check that we have guessed the geometry right by checking the
262 * Check for overlaps.
263 * Check against d_secperunit if the latter is reliable.
266 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) {
267 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0
268 && dp->dp_start == 0 && dp->dp_size == 0)
270 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart,
274 * Temporarily ignore errors from this check. We could
275 * simplify things by accepting the table eariler if we
276 * always ignore errors here. Perhaps we should always
277 * accept the table if the magic is right but not let
278 * bad entries affect the geometry.
280 check_part(sname, dp, mbr_offset, max_nsectors, max_ntracks,
287 * Accept the DOS partition table.
288 * First adjust the label (we have been careful not to change it
289 * before we can guarantee success).
291 secpercyl = (u_long)max_nsectors * max_ntracks;
292 if (secpercyl != 0) {
297 lp->d_nsectors = max_nsectors;
298 lp->d_ntracks = max_ntracks;
299 lp->d_secpercyl = secpercyl;
301 * Temporarily, don't even consider adjusting the drive's
302 * size, since the adjusted size may exceed the hardware's
303 * addressing capabilities. The adjustment helped mainly
304 * for ancient MFM drives with > 1024 cylinders, but now
305 * breaks at least IDE drives with 63*16*65536 sectors if
306 * they are controlled by the wd driver in CHS mode.
309 secperunit = secpercyl * max_ncyls;
310 if (lp->d_secperunit < secperunit)
311 lp->d_secperunit = secperunit;
313 lp->d_ncylinders = lp->d_secperunit / secpercyl;
317 * We are passed a pointer to a suitably initialized minimal
318 * slices "struct" with no dangling pointers in it. Replace it
319 * by a maximal one. This usually oversizes the "struct", but
320 * enlarging it while searching for logical drives would be
323 free(*sspp, M_DEVBUF);
324 ssp = dsmakeslicestruct(MAX_SLICES, lp);
327 /* Initialize normal slices. */
328 sp = &ssp->dss_slices[BASE_SLICE];
329 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) {
330 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart,
332 (void)mbr_setslice(sname, lp, sp, dp, mbr_offset);
334 ssp->dss_nslices = BASE_SLICE + NDOSPART;
336 /* Handle extended partitions. */
338 for (dospart = 0; dospart < NDOSPART; dospart++, sp++) {
339 if (sp->ds_type == DOSPTYP_EXTENDED ||
340 sp->ds_type == DOSPTYP_EXTENDEDX) {
341 mbr_extended(wdev, lp, ssp,
342 sp->ds_offset, sp->ds_size, sp->ds_offset,
343 max_nsectors, max_ntracks, mbr_offset, 1);
348 * mbr_extended() abuses ssp->dss_nslices for the number of slices
349 * that would be found if there were no limit on the number of slices
350 * in *ssp. Cut it back now.
352 if (ssp->dss_nslices > MAX_SLICES)
353 ssp->dss_nslices = MAX_SLICES;
356 bp->b_flags |= B_INVAL | B_AGE;
364 mbr_extended(dev_t dev, struct disklabel *lp, struct diskslices *ssp,
365 u_long ext_offset, u_long ext_size, u_long base_ext_offset,
366 int nsectors, int ntracks, u_long mbr_offset, int level)
371 struct dos_partition *dp;
372 struct dos_partition dpcopy[NDOSPART];
373 u_long ext_offsets[NDOSPART];
374 u_long ext_sizes[NDOSPART];
378 struct diskslice *sp;
382 "%s: excessive recursion in search for slices; aborting search\n",
387 /* Read extended boot record. */
388 bp = geteblk((int)lp->d_secsize);
389 bp->b_bio1.bio_offset = (off_t)ext_offset * lp->d_secsize;
390 bp->b_bcount = lp->d_secsize;
391 bp->b_cmd = BUF_CMD_READ;
392 dev_dstrategy(dev, &bp->b_bio1);
393 if (biowait(bp) != 0) {
394 diskerr(&bp->b_bio1, dev,
395 "reading extended partition table: error",
396 LOG_PRINTF, 0, NULL);
401 /* Weakly verify it. */
403 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) {
404 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, RAW_PART,
407 printf("%s: invalid extended partition table: no magic\n",
412 /* Make a copy of the partition table to avoid alignment problems. */
413 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy));
415 slice = ssp->dss_nslices;
416 for (dospart = 0, dp = &dpcopy[0]; dospart < NDOSPART;
418 ext_sizes[dospart] = 0;
419 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0
420 && dp->dp_start == 0 && dp->dp_size == 0)
422 if (dp->dp_typ == DOSPTYP_EXTENDED ||
423 dp->dp_typ == DOSPTYP_EXTENDEDX) {
426 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE,
428 snprintf(buf, sizeof(buf), "%s", sname);
429 if (strlen(buf) < sizeof buf - 11)
430 strcat(buf, "<extended>");
431 check_part(buf, dp, base_ext_offset, nsectors,
432 ntracks, mbr_offset);
433 ext_offsets[dospart] = base_ext_offset + dp->dp_start;
434 ext_sizes[dospart] = dp->dp_size;
436 sname = dsname(dev, dkunit(dev), slice, RAW_PART,
438 check_part(sname, dp, ext_offset, nsectors, ntracks,
440 if (slice >= MAX_SLICES) {
441 printf("%s: too many slices\n", sname);
445 sp = &ssp->dss_slices[slice];
446 if (mbr_setslice(sname, lp, sp, dp, ext_offset) != 0)
451 ssp->dss_nslices = slice;
453 /* If we found any more slices, recursively find all the subslices. */
454 for (dospart = 0; dospart < NDOSPART; dospart++) {
455 if (ext_sizes[dospart] != 0) {
456 mbr_extended(dev, lp, ssp, ext_offsets[dospart],
457 ext_sizes[dospart], base_ext_offset,
458 nsectors, ntracks, mbr_offset, ++level);
463 bp->b_flags |= B_INVAL | B_AGE;
468 mbr_setslice(char *sname, struct disklabel *lp, struct diskslice *sp,
469 struct dos_partition *dp, u_long br_offset)
474 offset = br_offset + dp->dp_start;
475 if (offset > lp->d_secperunit || offset < br_offset) {
477 "%s: slice starts beyond end of the disk: rejecting it\n",
481 size = lp->d_secperunit - offset;
482 if (size >= dp->dp_size)
486 "%s: slice extends beyond end of disk: truncating from %lu to %lu sectors\n",
487 sname, (u_long)dp->dp_size, size);
488 sp->ds_offset = offset;
490 sp->ds_type = dp->dp_typ;
492 lp->d_subtype |= (lp->d_subtype & 3) | dospart | DSTYPE_INDOSPART;