2 * Copyright (c) 2007, 2008 Marcel Moolenaar
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
32 #include <sys/diskmbr.h>
33 #include <sys/endian.h>
34 #include <sys/kernel.h>
36 #include <sys/limits.h>
38 #include <sys/malloc.h>
39 #include <sys/mutex.h>
40 #include <sys/queue.h>
42 #include <sys/systm.h>
43 #include <sys/sysctl.h>
44 #include <geom/geom.h>
45 #include <geom/geom_int.h>
46 #include <geom/part/g_part.h>
48 #include "g_part_if.h"
50 FEATURE(geom_part_mbr, "GEOM partitioning class for MBR support");
52 SYSCTL_DECL(_kern_geom_part);
53 static SYSCTL_NODE(_kern_geom_part, OID_AUTO, mbr, CTLFLAG_RW, 0,
54 "GEOM_PART_MBR Master Boot Record");
56 static u_int enforce_chs = 1;
57 SYSCTL_UINT(_kern_geom_part_mbr, OID_AUTO, enforce_chs,
58 CTLFLAG_RWTUN, &enforce_chs, 1, "Enforce alignment to CHS addressing");
62 struct g_part_mbr_table {
63 struct g_part_table base;
67 struct g_part_mbr_entry {
68 struct g_part_entry base;
69 struct dos_partition ent;
72 static int g_part_mbr_add(struct g_part_table *, struct g_part_entry *,
73 struct g_part_parms *);
74 static int g_part_mbr_bootcode(struct g_part_table *, struct g_part_parms *);
75 static int g_part_mbr_create(struct g_part_table *, struct g_part_parms *);
76 static int g_part_mbr_destroy(struct g_part_table *, struct g_part_parms *);
77 static void g_part_mbr_dumpconf(struct g_part_table *, struct g_part_entry *,
78 struct sbuf *, const char *);
79 static int g_part_mbr_dumpto(struct g_part_table *, struct g_part_entry *);
80 static int g_part_mbr_modify(struct g_part_table *, struct g_part_entry *,
81 struct g_part_parms *);
82 static const char *g_part_mbr_name(struct g_part_table *, struct g_part_entry *,
84 static int g_part_mbr_probe(struct g_part_table *, struct g_consumer *);
85 static int g_part_mbr_read(struct g_part_table *, struct g_consumer *);
86 static int g_part_mbr_setunset(struct g_part_table *, struct g_part_entry *,
87 const char *, unsigned int);
88 static const char *g_part_mbr_type(struct g_part_table *, struct g_part_entry *,
90 static int g_part_mbr_write(struct g_part_table *, struct g_consumer *);
91 static int g_part_mbr_resize(struct g_part_table *, struct g_part_entry *,
92 struct g_part_parms *);
94 static kobj_method_t g_part_mbr_methods[] = {
95 KOBJMETHOD(g_part_add, g_part_mbr_add),
96 KOBJMETHOD(g_part_bootcode, g_part_mbr_bootcode),
97 KOBJMETHOD(g_part_create, g_part_mbr_create),
98 KOBJMETHOD(g_part_destroy, g_part_mbr_destroy),
99 KOBJMETHOD(g_part_dumpconf, g_part_mbr_dumpconf),
100 KOBJMETHOD(g_part_dumpto, g_part_mbr_dumpto),
101 KOBJMETHOD(g_part_modify, g_part_mbr_modify),
102 KOBJMETHOD(g_part_resize, g_part_mbr_resize),
103 KOBJMETHOD(g_part_name, g_part_mbr_name),
104 KOBJMETHOD(g_part_probe, g_part_mbr_probe),
105 KOBJMETHOD(g_part_read, g_part_mbr_read),
106 KOBJMETHOD(g_part_setunset, g_part_mbr_setunset),
107 KOBJMETHOD(g_part_type, g_part_mbr_type),
108 KOBJMETHOD(g_part_write, g_part_mbr_write),
112 static struct g_part_scheme g_part_mbr_scheme = {
115 sizeof(struct g_part_mbr_table),
116 .gps_entrysz = sizeof(struct g_part_mbr_entry),
117 .gps_minent = NDOSPART,
118 .gps_maxent = NDOSPART,
119 .gps_bootcodesz = MBRSIZE,
121 G_PART_SCHEME_DECLARE(g_part_mbr);
123 static struct g_part_mbr_alias {
126 } mbr_alias_match[] = {
127 { DOSPTYP_386BSD, G_PART_ALIAS_FREEBSD },
128 { DOSPTYP_EXT, G_PART_ALIAS_EBR },
129 { DOSPTYP_NTFS, G_PART_ALIAS_MS_NTFS },
130 { DOSPTYP_FAT16, G_PART_ALIAS_MS_FAT16 },
131 { DOSPTYP_FAT32, G_PART_ALIAS_MS_FAT32 },
132 { DOSPTYP_EXTLBA, G_PART_ALIAS_EBR },
133 { DOSPTYP_LDM, G_PART_ALIAS_MS_LDM_DATA },
134 { DOSPTYP_LINSWP, G_PART_ALIAS_LINUX_SWAP },
135 { DOSPTYP_LINUX, G_PART_ALIAS_LINUX_DATA },
136 { DOSPTYP_LINLVM, G_PART_ALIAS_LINUX_LVM },
137 { DOSPTYP_LINRAID, G_PART_ALIAS_LINUX_RAID },
138 { DOSPTYP_PPCBOOT, G_PART_ALIAS_PREP_BOOT },
139 { DOSPTYP_VMFS, G_PART_ALIAS_VMFS },
140 { DOSPTYP_VMKDIAG, G_PART_ALIAS_VMKDIAG },
141 { DOSPTYP_APPLE_UFS, G_PART_ALIAS_APPLE_UFS },
142 { DOSPTYP_APPLE_BOOT, G_PART_ALIAS_APPLE_BOOT },
143 { DOSPTYP_HFS, G_PART_ALIAS_APPLE_HFS },
147 mbr_parse_type(const char *type, u_char *dp_typ)
154 if (type[0] == '!') {
155 lt = strtol(type + 1, &endp, 0);
156 if (type[1] == '\0' || *endp != '\0' || lt <= 0 || lt >= 256)
158 *dp_typ = (u_char)lt;
162 i < sizeof(mbr_alias_match) / sizeof(mbr_alias_match[0]); i++) {
163 alias = g_part_alias_name(mbr_alias_match[i].alias);
164 if (strcasecmp(type, alias) == 0) {
165 *dp_typ = mbr_alias_match[i].typ;
173 mbr_probe_bpb(u_char *bpb)
178 #define PO2(x) ((x & (x - 1)) == 0)
179 secsz = le16dec(bpb);
180 if (secsz < 512 || secsz > 4096 || !PO2(secsz))
183 if (clstsz < 1 || clstsz > 128 || !PO2(clstsz))
191 mbr_set_chs(struct g_part_table *table, uint32_t lba, u_char *cylp, u_char *hdp,
194 uint32_t cyl, hd, sec;
196 sec = lba % table->gpt_sectors + 1;
197 lba /= table->gpt_sectors;
198 hd = lba % table->gpt_heads;
199 lba /= table->gpt_heads;
206 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0);
210 mbr_align(struct g_part_table *basetable, uint32_t *start, uint32_t *size)
214 if (enforce_chs == 0)
216 sectors = basetable->gpt_sectors;
219 if (start != NULL && (*start % sectors)) {
220 *size += (*start % sectors) - sectors;
221 *start -= (*start % sectors) - sectors;
224 *size -= (*size % sectors);
231 g_part_mbr_add(struct g_part_table *basetable, struct g_part_entry *baseentry,
232 struct g_part_parms *gpp)
234 struct g_part_mbr_entry *entry;
235 uint32_t start, size;
237 if (gpp->gpp_parms & G_PART_PARM_LABEL)
240 entry = (struct g_part_mbr_entry *)baseentry;
241 start = gpp->gpp_start;
242 size = gpp->gpp_size;
243 if (mbr_align(basetable, &start, &size) != 0)
245 if (baseentry->gpe_deleted)
246 bzero(&entry->ent, sizeof(entry->ent));
248 KASSERT(baseentry->gpe_start <= start, ("%s", __func__));
249 KASSERT(baseentry->gpe_end >= start + size - 1, ("%s", __func__));
250 baseentry->gpe_start = start;
251 baseentry->gpe_end = start + size - 1;
252 entry->ent.dp_start = start;
253 entry->ent.dp_size = size;
254 mbr_set_chs(basetable, baseentry->gpe_start, &entry->ent.dp_scyl,
255 &entry->ent.dp_shd, &entry->ent.dp_ssect);
256 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl,
257 &entry->ent.dp_ehd, &entry->ent.dp_esect);
258 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ));
262 g_part_mbr_bootcode(struct g_part_table *basetable, struct g_part_parms *gpp)
264 struct g_part_mbr_table *table;
267 if (gpp->gpp_codesize != MBRSIZE)
270 table = (struct g_part_mbr_table *)basetable;
271 dsn = *(uint32_t *)(table->mbr + DOSDSNOFF);
272 bcopy(gpp->gpp_codeptr, table->mbr, DOSPARTOFF);
274 *(uint32_t *)(table->mbr + DOSDSNOFF) = dsn;
279 g_part_mbr_create(struct g_part_table *basetable, struct g_part_parms *gpp)
281 struct g_provider *pp;
282 struct g_part_mbr_table *table;
284 pp = gpp->gpp_provider;
285 if (pp->sectorsize < MBRSIZE)
288 basetable->gpt_first = basetable->gpt_sectors;
289 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize,
292 table = (struct g_part_mbr_table *)basetable;
293 le16enc(table->mbr + DOSMAGICOFFSET, DOSMAGIC);
298 g_part_mbr_destroy(struct g_part_table *basetable, struct g_part_parms *gpp)
301 /* Wipe the first sector to clear the partitioning. */
302 basetable->gpt_smhead |= 1;
307 g_part_mbr_dumpconf(struct g_part_table *table, struct g_part_entry *baseentry,
308 struct sbuf *sb, const char *indent)
310 struct g_part_mbr_entry *entry;
312 entry = (struct g_part_mbr_entry *)baseentry;
313 if (indent == NULL) {
314 /* conftxt: libdisk compatibility */
315 sbuf_printf(sb, " xs MBR xt %u", entry->ent.dp_typ);
316 } else if (entry != NULL) {
317 /* confxml: partition entry information */
318 sbuf_printf(sb, "%s<rawtype>%u</rawtype>\n", indent,
320 if (entry->ent.dp_flag & 0x80)
321 sbuf_printf(sb, "%s<attrib>active</attrib>\n", indent);
323 /* confxml: scheme information */
328 g_part_mbr_dumpto(struct g_part_table *table, struct g_part_entry *baseentry)
330 struct g_part_mbr_entry *entry;
332 /* Allow dumping to a FreeBSD partition or Linux swap partition only. */
333 entry = (struct g_part_mbr_entry *)baseentry;
334 return ((entry->ent.dp_typ == DOSPTYP_386BSD ||
335 entry->ent.dp_typ == DOSPTYP_LINSWP) ? 1 : 0);
339 g_part_mbr_modify(struct g_part_table *basetable,
340 struct g_part_entry *baseentry, struct g_part_parms *gpp)
342 struct g_part_mbr_entry *entry;
344 if (gpp->gpp_parms & G_PART_PARM_LABEL)
347 entry = (struct g_part_mbr_entry *)baseentry;
348 if (gpp->gpp_parms & G_PART_PARM_TYPE)
349 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ));
354 g_part_mbr_resize(struct g_part_table *basetable,
355 struct g_part_entry *baseentry, struct g_part_parms *gpp)
357 struct g_part_mbr_entry *entry;
358 struct g_provider *pp;
361 if (baseentry == NULL) {
362 pp = LIST_FIRST(&basetable->gpt_gp->consumer)->provider;
363 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize,
367 size = gpp->gpp_size;
368 if (mbr_align(basetable, NULL, &size) != 0)
370 /* XXX: prevent unexpected shrinking. */
371 pp = baseentry->gpe_pp;
372 if ((g_debugflags & 0x10) == 0 && size < gpp->gpp_size &&
373 pp->mediasize / pp->sectorsize > size)
375 entry = (struct g_part_mbr_entry *)baseentry;
376 baseentry->gpe_end = baseentry->gpe_start + size - 1;
377 entry->ent.dp_size = size;
378 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl,
379 &entry->ent.dp_ehd, &entry->ent.dp_esect);
384 g_part_mbr_name(struct g_part_table *table, struct g_part_entry *baseentry,
385 char *buf, size_t bufsz)
388 snprintf(buf, bufsz, "s%d", baseentry->gpe_index);
393 g_part_mbr_probe(struct g_part_table *table, struct g_consumer *cp)
396 struct g_provider *pp;
398 int error, index, res, sum;
403 /* Sanity-check the provider. */
404 if (pp->sectorsize < MBRSIZE || pp->mediasize < pp->sectorsize)
406 if (pp->sectorsize > 4096)
409 /* We don't nest under an MBR (see EBR instead). */
410 error = g_getattr("PART::scheme", cp, &psn);
411 if (error == 0 && strcmp(psn, g_part_mbr_scheme.name) == 0)
414 /* Check that there's a MBR. */
415 buf = g_read_data(cp, 0L, pp->sectorsize, &error);
419 /* We goto out on mismatch. */
422 magic = le16dec(buf + DOSMAGICOFFSET);
423 if (magic != DOSMAGIC)
426 for (index = 0; index < NDOSPART; index++) {
427 p = buf + DOSPARTOFF + index * DOSPARTSIZE;
428 if (p[0] != 0 && p[0] != 0x80)
433 * If the partition table does not consist of all zeroes,
434 * assume we have a MBR. If it's all zeroes, we could have
435 * a boot sector. For example, a boot sector that doesn't
436 * have boot code -- common on non-i386 hardware. In that
437 * case we check if we have a possible BPB. If so, then we
438 * assume we have a boot sector instead.
441 for (index = 0; index < NDOSPART * DOSPARTSIZE; index++)
442 sum += buf[DOSPARTOFF + index];
443 if (sum != 0 || !mbr_probe_bpb(buf + 0x0b))
444 res = G_PART_PROBE_PRI_NORM;
452 g_part_mbr_read(struct g_part_table *basetable, struct g_consumer *cp)
454 struct dos_partition ent;
455 struct g_provider *pp;
456 struct g_part_mbr_table *table;
457 struct g_part_mbr_entry *entry;
459 off_t chs, msize, first;
460 u_int sectors, heads;
464 table = (struct g_part_mbr_table *)basetable;
465 first = basetable->gpt_sectors;
466 msize = MIN(pp->mediasize / pp->sectorsize, UINT32_MAX);
468 buf = g_read_data(cp, 0L, pp->sectorsize, &error);
472 bcopy(buf, table->mbr, sizeof(table->mbr));
473 for (index = NDOSPART - 1; index >= 0; index--) {
474 p = buf + DOSPARTOFF + index * DOSPARTSIZE;
483 ent.dp_start = le32dec(p + 8);
484 ent.dp_size = le32dec(p + 12);
485 if (ent.dp_typ == 0 || ent.dp_typ == DOSPTYP_PMBR)
487 if (ent.dp_start == 0 || ent.dp_size == 0)
489 sectors = ent.dp_esect & 0x3f;
490 if (sectors > basetable->gpt_sectors &&
491 !basetable->gpt_fixgeom) {
492 g_part_geometry_heads(msize, sectors, &chs, &heads);
494 basetable->gpt_sectors = sectors;
495 basetable->gpt_heads = heads;
498 if (ent.dp_start < first)
499 first = ent.dp_start;
500 entry = (struct g_part_mbr_entry *)g_part_new_entry(basetable,
501 index + 1, ent.dp_start, ent.dp_start + ent.dp_size - 1);
505 basetable->gpt_entries = NDOSPART;
506 basetable->gpt_first = basetable->gpt_sectors;
507 basetable->gpt_last = msize - 1;
509 if (first < basetable->gpt_first)
510 basetable->gpt_first = 1;
517 g_part_mbr_setunset(struct g_part_table *table, struct g_part_entry *baseentry,
518 const char *attrib, unsigned int set)
520 struct g_part_entry *iter;
521 struct g_part_mbr_entry *entry;
524 if (baseentry == NULL)
526 if (strcasecmp(attrib, "active") != 0)
529 /* Only one entry can have the active attribute. */
530 LIST_FOREACH(iter, &table->gpt_entry, gpe_entry) {
531 if (iter->gpe_deleted)
534 entry = (struct g_part_mbr_entry *)iter;
535 if (iter == baseentry) {
536 if (set && (entry->ent.dp_flag & 0x80) == 0) {
537 entry->ent.dp_flag |= 0x80;
539 } else if (!set && (entry->ent.dp_flag & 0x80)) {
540 entry->ent.dp_flag &= ~0x80;
544 if (set && (entry->ent.dp_flag & 0x80)) {
545 entry->ent.dp_flag &= ~0x80;
549 if (changed && !iter->gpe_created)
550 iter->gpe_modified = 1;
556 g_part_mbr_type(struct g_part_table *basetable, struct g_part_entry *baseentry,
557 char *buf, size_t bufsz)
559 struct g_part_mbr_entry *entry;
562 entry = (struct g_part_mbr_entry *)baseentry;
564 i < sizeof(mbr_alias_match) / sizeof(mbr_alias_match[0]); i++) {
565 if (mbr_alias_match[i].typ == entry->ent.dp_typ)
566 return (g_part_alias_name(mbr_alias_match[i].alias));
568 snprintf(buf, bufsz, "!%d", entry->ent.dp_typ);
573 g_part_mbr_write(struct g_part_table *basetable, struct g_consumer *cp)
575 struct g_part_entry *baseentry;
576 struct g_part_mbr_entry *entry;
577 struct g_part_mbr_table *table;
581 table = (struct g_part_mbr_table *)basetable;
582 baseentry = LIST_FIRST(&basetable->gpt_entry);
583 for (index = 1; index <= basetable->gpt_entries; index++) {
584 p = table->mbr + DOSPARTOFF + (index - 1) * DOSPARTSIZE;
585 entry = (baseentry != NULL && index == baseentry->gpe_index)
586 ? (struct g_part_mbr_entry *)baseentry : NULL;
587 if (entry != NULL && !baseentry->gpe_deleted) {
588 p[0] = entry->ent.dp_flag;
589 p[1] = entry->ent.dp_shd;
590 p[2] = entry->ent.dp_ssect;
591 p[3] = entry->ent.dp_scyl;
592 p[4] = entry->ent.dp_typ;
593 p[5] = entry->ent.dp_ehd;
594 p[6] = entry->ent.dp_esect;
595 p[7] = entry->ent.dp_ecyl;
596 le32enc(p + 8, entry->ent.dp_start);
597 le32enc(p + 12, entry->ent.dp_size);
599 bzero(p, DOSPARTSIZE);
602 baseentry = LIST_NEXT(baseentry, gpe_entry);
605 error = g_write_data(cp, 0, table->mbr, cp->provider->sectorsize);