2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2007, 2008 Marcel Moolenaar
7 * Redistribution and use in source and binary forms, with or without
8 * 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.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
32 #include <sys/param.h>
34 #include <sys/diskmbr.h>
35 #include <sys/endian.h>
36 #include <sys/kernel.h>
38 #include <sys/limits.h>
40 #include <sys/malloc.h>
41 #include <sys/mutex.h>
42 #include <sys/queue.h>
44 #include <sys/systm.h>
45 #include <sys/sysctl.h>
46 #include <geom/geom.h>
47 #include <geom/geom_int.h>
48 #include <geom/part/g_part.h>
50 #include "g_part_if.h"
52 FEATURE(geom_part_mbr, "GEOM partitioning class for MBR support");
54 SYSCTL_DECL(_kern_geom_part);
55 static SYSCTL_NODE(_kern_geom_part, OID_AUTO, mbr, CTLFLAG_RW, 0,
56 "GEOM_PART_MBR Master Boot Record");
58 static u_int enforce_chs = 0;
59 SYSCTL_UINT(_kern_geom_part_mbr, OID_AUTO, enforce_chs,
60 CTLFLAG_RWTUN, &enforce_chs, 0, "Enforce alignment to CHS addressing");
64 struct g_part_mbr_table {
65 struct g_part_table base;
69 struct g_part_mbr_entry {
70 struct g_part_entry base;
71 struct dos_partition ent;
74 static int g_part_mbr_add(struct g_part_table *, struct g_part_entry *,
75 struct g_part_parms *);
76 static int g_part_mbr_bootcode(struct g_part_table *, struct g_part_parms *);
77 static int g_part_mbr_create(struct g_part_table *, struct g_part_parms *);
78 static int g_part_mbr_destroy(struct g_part_table *, struct g_part_parms *);
79 static void g_part_mbr_dumpconf(struct g_part_table *, struct g_part_entry *,
80 struct sbuf *, const char *);
81 static int g_part_mbr_dumpto(struct g_part_table *, struct g_part_entry *);
82 static int g_part_mbr_modify(struct g_part_table *, struct g_part_entry *,
83 struct g_part_parms *);
84 static const char *g_part_mbr_name(struct g_part_table *, struct g_part_entry *,
86 static int g_part_mbr_probe(struct g_part_table *, struct g_consumer *);
87 static int g_part_mbr_read(struct g_part_table *, struct g_consumer *);
88 static int g_part_mbr_setunset(struct g_part_table *, struct g_part_entry *,
89 const char *, unsigned int);
90 static const char *g_part_mbr_type(struct g_part_table *, struct g_part_entry *,
92 static int g_part_mbr_write(struct g_part_table *, struct g_consumer *);
93 static int g_part_mbr_resize(struct g_part_table *, struct g_part_entry *,
94 struct g_part_parms *);
96 static kobj_method_t g_part_mbr_methods[] = {
97 KOBJMETHOD(g_part_add, g_part_mbr_add),
98 KOBJMETHOD(g_part_bootcode, g_part_mbr_bootcode),
99 KOBJMETHOD(g_part_create, g_part_mbr_create),
100 KOBJMETHOD(g_part_destroy, g_part_mbr_destroy),
101 KOBJMETHOD(g_part_dumpconf, g_part_mbr_dumpconf),
102 KOBJMETHOD(g_part_dumpto, g_part_mbr_dumpto),
103 KOBJMETHOD(g_part_modify, g_part_mbr_modify),
104 KOBJMETHOD(g_part_resize, g_part_mbr_resize),
105 KOBJMETHOD(g_part_name, g_part_mbr_name),
106 KOBJMETHOD(g_part_probe, g_part_mbr_probe),
107 KOBJMETHOD(g_part_read, g_part_mbr_read),
108 KOBJMETHOD(g_part_setunset, g_part_mbr_setunset),
109 KOBJMETHOD(g_part_type, g_part_mbr_type),
110 KOBJMETHOD(g_part_write, g_part_mbr_write),
114 static struct g_part_scheme g_part_mbr_scheme = {
117 sizeof(struct g_part_mbr_table),
118 .gps_entrysz = sizeof(struct g_part_mbr_entry),
119 .gps_minent = NDOSPART,
120 .gps_maxent = NDOSPART,
121 .gps_bootcodesz = MBRSIZE,
123 G_PART_SCHEME_DECLARE(g_part_mbr);
124 MODULE_VERSION(geom_part_mbr, 0);
126 static struct g_part_mbr_alias {
129 } mbr_alias_match[] = {
130 { DOSPTYP_386BSD, G_PART_ALIAS_FREEBSD },
131 { DOSPTYP_APPLE_BOOT, G_PART_ALIAS_APPLE_BOOT },
132 { DOSPTYP_APPLE_UFS, G_PART_ALIAS_APPLE_UFS },
133 { DOSPTYP_EFI, G_PART_ALIAS_EFI },
134 { DOSPTYP_EXT, G_PART_ALIAS_EBR },
135 { DOSPTYP_EXTLBA, G_PART_ALIAS_EBR },
136 { DOSPTYP_FAT16, G_PART_ALIAS_MS_FAT16 },
137 { DOSPTYP_FAT32, G_PART_ALIAS_MS_FAT32 },
138 { DOSPTYP_FAT32LBA, G_PART_ALIAS_MS_FAT32LBA },
139 { DOSPTYP_HFS, G_PART_ALIAS_APPLE_HFS },
140 { DOSPTYP_LDM, G_PART_ALIAS_MS_LDM_DATA },
141 { DOSPTYP_LINLVM, G_PART_ALIAS_LINUX_LVM },
142 { DOSPTYP_LINRAID, G_PART_ALIAS_LINUX_RAID },
143 { DOSPTYP_LINSWP, G_PART_ALIAS_LINUX_SWAP },
144 { DOSPTYP_LINUX, G_PART_ALIAS_LINUX_DATA },
145 { DOSPTYP_NTFS, G_PART_ALIAS_MS_NTFS },
146 { DOSPTYP_PPCBOOT, G_PART_ALIAS_PREP_BOOT },
147 { DOSPTYP_VMFS, G_PART_ALIAS_VMFS },
148 { DOSPTYP_VMKDIAG, G_PART_ALIAS_VMKDIAG },
152 mbr_parse_type(const char *type, u_char *dp_typ)
159 if (type[0] == '!') {
160 lt = strtol(type + 1, &endp, 0);
161 if (type[1] == '\0' || *endp != '\0' || lt <= 0 || lt >= 256)
163 *dp_typ = (u_char)lt;
166 for (i = 0; i < nitems(mbr_alias_match); i++) {
167 alias = g_part_alias_name(mbr_alias_match[i].alias);
168 if (strcasecmp(type, alias) == 0) {
169 *dp_typ = mbr_alias_match[i].typ;
177 mbr_probe_bpb(u_char *bpb)
182 #define PO2(x) ((x & (x - 1)) == 0)
183 secsz = le16dec(bpb);
184 if (secsz < 512 || secsz > 4096 || !PO2(secsz))
187 if (clstsz < 1 || clstsz > 128 || !PO2(clstsz))
195 mbr_set_chs(struct g_part_table *table, uint32_t lba, u_char *cylp, u_char *hdp,
198 uint32_t cyl, hd, sec;
200 sec = lba % table->gpt_sectors + 1;
201 lba /= table->gpt_sectors;
202 hd = lba % table->gpt_heads;
203 lba /= table->gpt_heads;
210 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0);
214 mbr_align(struct g_part_table *basetable, uint32_t *start, uint32_t *size)
218 if (enforce_chs == 0)
220 sectors = basetable->gpt_sectors;
223 if (start != NULL && (*start % sectors)) {
224 *size += (*start % sectors) - sectors;
225 *start -= (*start % sectors) - sectors;
228 *size -= (*size % sectors);
235 g_part_mbr_add(struct g_part_table *basetable, struct g_part_entry *baseentry,
236 struct g_part_parms *gpp)
238 struct g_part_mbr_entry *entry;
239 uint32_t start, size;
241 if (gpp->gpp_parms & G_PART_PARM_LABEL)
244 entry = (struct g_part_mbr_entry *)baseentry;
245 start = gpp->gpp_start;
246 size = gpp->gpp_size;
247 if (mbr_align(basetable, &start, &size) != 0)
249 if (baseentry->gpe_deleted)
250 bzero(&entry->ent, sizeof(entry->ent));
252 KASSERT(baseentry->gpe_start <= start, ("%s", __func__));
253 KASSERT(baseentry->gpe_end >= start + size - 1, ("%s", __func__));
254 baseentry->gpe_start = start;
255 baseentry->gpe_end = start + size - 1;
256 entry->ent.dp_start = start;
257 entry->ent.dp_size = size;
258 mbr_set_chs(basetable, baseentry->gpe_start, &entry->ent.dp_scyl,
259 &entry->ent.dp_shd, &entry->ent.dp_ssect);
260 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl,
261 &entry->ent.dp_ehd, &entry->ent.dp_esect);
262 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ));
266 g_part_mbr_bootcode(struct g_part_table *basetable, struct g_part_parms *gpp)
268 struct g_part_mbr_table *table;
271 if (gpp->gpp_codesize != MBRSIZE)
274 table = (struct g_part_mbr_table *)basetable;
275 dsn = *(uint32_t *)(table->mbr + DOSDSNOFF);
276 bcopy(gpp->gpp_codeptr, table->mbr, DOSPARTOFF);
277 if (dsn != 0 && !gpp->gpp_skip_dsn)
278 *(uint32_t *)(table->mbr + DOSDSNOFF) = dsn;
283 g_part_mbr_create(struct g_part_table *basetable, struct g_part_parms *gpp)
285 struct g_provider *pp;
286 struct g_part_mbr_table *table;
288 pp = gpp->gpp_provider;
289 if (pp->sectorsize < MBRSIZE)
292 basetable->gpt_first = basetable->gpt_sectors;
293 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize,
296 table = (struct g_part_mbr_table *)basetable;
297 le16enc(table->mbr + DOSMAGICOFFSET, DOSMAGIC);
302 g_part_mbr_destroy(struct g_part_table *basetable, struct g_part_parms *gpp)
305 /* Wipe the first sector to clear the partitioning. */
306 basetable->gpt_smhead |= 1;
311 g_part_mbr_dumpconf(struct g_part_table *basetable, struct g_part_entry *baseentry,
312 struct sbuf *sb, const char *indent)
314 struct g_part_mbr_entry *entry;
315 struct g_part_mbr_table *table;
318 table = (struct g_part_mbr_table *)basetable;
319 entry = (struct g_part_mbr_entry *)baseentry;
320 if (indent == NULL) {
321 /* conftxt: libdisk compatibility */
322 sbuf_printf(sb, " xs MBR xt %u", entry->ent.dp_typ);
323 } else if (entry != NULL) {
324 /* confxml: partition entry information */
325 sbuf_printf(sb, "%s<rawtype>%u</rawtype>\n", indent,
327 if (entry->ent.dp_flag & 0x80)
328 sbuf_printf(sb, "%s<attrib>active</attrib>\n", indent);
329 dsn = le32dec(table->mbr + DOSDSNOFF);
330 sbuf_printf(sb, "%s<efimedia>HD(%d,MBR,%#08x,%#jx,%#jx)", indent,
331 entry->base.gpe_index, dsn, (intmax_t)entry->base.gpe_start,
332 (intmax_t)(entry->base.gpe_end - entry->base.gpe_start + 1));
333 sbuf_printf(sb, "</efimedia>\n");
335 /* confxml: scheme information */
340 g_part_mbr_dumpto(struct g_part_table *table, struct g_part_entry *baseentry)
342 struct g_part_mbr_entry *entry;
344 /* Allow dumping to a FreeBSD partition or Linux swap partition only. */
345 entry = (struct g_part_mbr_entry *)baseentry;
346 return ((entry->ent.dp_typ == DOSPTYP_386BSD ||
347 entry->ent.dp_typ == DOSPTYP_LINSWP) ? 1 : 0);
351 g_part_mbr_modify(struct g_part_table *basetable,
352 struct g_part_entry *baseentry, struct g_part_parms *gpp)
354 struct g_part_mbr_entry *entry;
356 if (gpp->gpp_parms & G_PART_PARM_LABEL)
359 entry = (struct g_part_mbr_entry *)baseentry;
360 if (gpp->gpp_parms & G_PART_PARM_TYPE)
361 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ));
366 g_part_mbr_resize(struct g_part_table *basetable,
367 struct g_part_entry *baseentry, struct g_part_parms *gpp)
369 struct g_part_mbr_entry *entry;
370 struct g_provider *pp;
373 if (baseentry == NULL) {
374 pp = LIST_FIRST(&basetable->gpt_gp->consumer)->provider;
375 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize,
379 size = gpp->gpp_size;
380 if (mbr_align(basetable, NULL, &size) != 0)
382 /* XXX: prevent unexpected shrinking. */
383 pp = baseentry->gpe_pp;
384 if ((g_debugflags & 0x10) == 0 && size < gpp->gpp_size &&
385 pp->mediasize / pp->sectorsize > size)
387 entry = (struct g_part_mbr_entry *)baseentry;
388 baseentry->gpe_end = baseentry->gpe_start + size - 1;
389 entry->ent.dp_size = size;
390 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl,
391 &entry->ent.dp_ehd, &entry->ent.dp_esect);
396 g_part_mbr_name(struct g_part_table *table, struct g_part_entry *baseentry,
397 char *buf, size_t bufsz)
400 snprintf(buf, bufsz, "s%d", baseentry->gpe_index);
405 g_part_mbr_probe(struct g_part_table *table, struct g_consumer *cp)
408 struct g_provider *pp;
410 int error, index, res, sum;
415 /* Sanity-check the provider. */
416 if (pp->sectorsize < MBRSIZE || pp->mediasize < pp->sectorsize)
418 if (pp->sectorsize > 4096)
421 /* We don't nest under an MBR (see EBR instead). */
422 error = g_getattr("PART::scheme", cp, &psn);
423 if (error == 0 && strcmp(psn, g_part_mbr_scheme.name) == 0)
426 /* Check that there's a MBR. */
427 buf = g_read_data(cp, 0L, pp->sectorsize, &error);
431 /* We goto out on mismatch. */
434 magic = le16dec(buf + DOSMAGICOFFSET);
435 if (magic != DOSMAGIC)
438 for (index = 0; index < NDOSPART; index++) {
439 p = buf + DOSPARTOFF + index * DOSPARTSIZE;
440 if (p[0] != 0 && p[0] != 0x80)
445 * If the partition table does not consist of all zeroes,
446 * assume we have a MBR. If it's all zeroes, we could have
447 * a boot sector. For example, a boot sector that doesn't
448 * have boot code -- common on non-i386 hardware. In that
449 * case we check if we have a possible BPB. If so, then we
450 * assume we have a boot sector instead.
453 for (index = 0; index < NDOSPART * DOSPARTSIZE; index++)
454 sum += buf[DOSPARTOFF + index];
455 if (sum != 0 || !mbr_probe_bpb(buf + 0x0b))
456 res = G_PART_PROBE_PRI_NORM;
464 g_part_mbr_read(struct g_part_table *basetable, struct g_consumer *cp)
466 struct dos_partition ent;
467 struct g_provider *pp;
468 struct g_part_mbr_table *table;
469 struct g_part_mbr_entry *entry;
471 off_t chs, msize, first;
472 u_int sectors, heads;
476 table = (struct g_part_mbr_table *)basetable;
477 first = basetable->gpt_sectors;
478 msize = MIN(pp->mediasize / pp->sectorsize, UINT32_MAX);
480 buf = g_read_data(cp, 0L, pp->sectorsize, &error);
484 bcopy(buf, table->mbr, sizeof(table->mbr));
485 for (index = NDOSPART - 1; index >= 0; index--) {
486 p = buf + DOSPARTOFF + index * DOSPARTSIZE;
495 ent.dp_start = le32dec(p + 8);
496 ent.dp_size = le32dec(p + 12);
497 if (ent.dp_typ == 0 || ent.dp_typ == DOSPTYP_PMBR)
499 if (ent.dp_start == 0 || ent.dp_size == 0)
501 sectors = ent.dp_esect & 0x3f;
502 if (sectors > basetable->gpt_sectors &&
503 !basetable->gpt_fixgeom) {
504 g_part_geometry_heads(msize, sectors, &chs, &heads);
506 basetable->gpt_sectors = sectors;
507 basetable->gpt_heads = heads;
510 if (ent.dp_start < first)
511 first = ent.dp_start;
512 entry = (struct g_part_mbr_entry *)g_part_new_entry(basetable,
513 index + 1, ent.dp_start, ent.dp_start + ent.dp_size - 1);
517 basetable->gpt_entries = NDOSPART;
518 basetable->gpt_first = basetable->gpt_sectors;
519 basetable->gpt_last = msize - 1;
521 if (first < basetable->gpt_first)
522 basetable->gpt_first = 1;
529 g_part_mbr_setunset(struct g_part_table *table, struct g_part_entry *baseentry,
530 const char *attrib, unsigned int set)
532 struct g_part_entry *iter;
533 struct g_part_mbr_entry *entry;
536 if (baseentry == NULL)
538 if (strcasecmp(attrib, "active") != 0)
541 /* Only one entry can have the active attribute. */
542 LIST_FOREACH(iter, &table->gpt_entry, gpe_entry) {
543 if (iter->gpe_deleted)
546 entry = (struct g_part_mbr_entry *)iter;
547 if (iter == baseentry) {
548 if (set && (entry->ent.dp_flag & 0x80) == 0) {
549 entry->ent.dp_flag |= 0x80;
551 } else if (!set && (entry->ent.dp_flag & 0x80)) {
552 entry->ent.dp_flag &= ~0x80;
556 if (set && (entry->ent.dp_flag & 0x80)) {
557 entry->ent.dp_flag &= ~0x80;
561 if (changed && !iter->gpe_created)
562 iter->gpe_modified = 1;
568 g_part_mbr_type(struct g_part_table *basetable, struct g_part_entry *baseentry,
569 char *buf, size_t bufsz)
571 struct g_part_mbr_entry *entry;
574 entry = (struct g_part_mbr_entry *)baseentry;
575 for (i = 0; i < nitems(mbr_alias_match); i++) {
576 if (mbr_alias_match[i].typ == entry->ent.dp_typ)
577 return (g_part_alias_name(mbr_alias_match[i].alias));
579 snprintf(buf, bufsz, "!%d", entry->ent.dp_typ);
584 g_part_mbr_write(struct g_part_table *basetable, struct g_consumer *cp)
586 struct g_part_entry *baseentry;
587 struct g_part_mbr_entry *entry;
588 struct g_part_mbr_table *table;
592 table = (struct g_part_mbr_table *)basetable;
593 baseentry = LIST_FIRST(&basetable->gpt_entry);
594 for (index = 1; index <= basetable->gpt_entries; index++) {
595 p = table->mbr + DOSPARTOFF + (index - 1) * DOSPARTSIZE;
596 entry = (baseentry != NULL && index == baseentry->gpe_index)
597 ? (struct g_part_mbr_entry *)baseentry : NULL;
598 if (entry != NULL && !baseentry->gpe_deleted) {
599 p[0] = entry->ent.dp_flag;
600 p[1] = entry->ent.dp_shd;
601 p[2] = entry->ent.dp_ssect;
602 p[3] = entry->ent.dp_scyl;
603 p[4] = entry->ent.dp_typ;
604 p[5] = entry->ent.dp_ehd;
605 p[6] = entry->ent.dp_esect;
606 p[7] = entry->ent.dp_ecyl;
607 le32enc(p + 8, entry->ent.dp_start);
608 le32enc(p + 12, entry->ent.dp_size);
610 bzero(p, DOSPARTSIZE);
613 baseentry = LIST_NEXT(baseentry, gpe_entry);
616 error = g_write_data(cp, 0, table->mbr, cp->provider->sectorsize);