1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2007, 2008 Marcel Moolenaar 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 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 * 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. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/bio.h> 34 #include <sys/diskmbr.h> 35 #include <sys/endian.h> 36 #include <sys/kernel.h> 37 #include <sys/kobj.h> 38 #include <sys/limits.h> 39 #include <sys/lock.h> 40 #include <sys/malloc.h> 41 #include <sys/mutex.h> 42 #include <sys/queue.h> 43 #include <sys/sbuf.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> 49 50 #include "g_part_if.h" 51 52 FEATURE(geom_part_mbr, "GEOM partitioning class for MBR support"); 53 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"); 57 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"); 61 62 #define MBRSIZE 512 63 64 struct g_part_mbr_table { 65 struct g_part_table base; 66 u_char mbr[MBRSIZE]; 67 }; 68 69 struct g_part_mbr_entry { 70 struct g_part_entry base; 71 struct dos_partition ent; 72 }; 73 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 *, 85 char *, size_t); 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 *, 91 char *, size_t); 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 *); 95 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), 111 { 0, 0 } 112 }; 113 114 static struct g_part_scheme g_part_mbr_scheme = { 115 "MBR", 116 g_part_mbr_methods, 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, 122 }; 123 G_PART_SCHEME_DECLARE(g_part_mbr); 124 MODULE_VERSION(geom_part_mbr, 0); 125 126 static struct g_part_mbr_alias { 127 u_char typ; 128 int 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 }, 149 }; 150 151 static int 152 mbr_parse_type(const char *type, u_char *dp_typ) 153 { 154 const char *alias; 155 char *endp; 156 long lt; 157 int i; 158 159 if (type[0] == '!') { 160 lt = strtol(type + 1, &endp, 0); 161 if (type[1] == '\0' || *endp != '\0' || lt <= 0 || lt >= 256) 162 return (EINVAL); 163 *dp_typ = (u_char)lt; 164 return (0); 165 } 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; 170 return (0); 171 } 172 } 173 return (EINVAL); 174 } 175 176 static int 177 mbr_probe_bpb(u_char *bpb) 178 { 179 uint16_t secsz; 180 uint8_t clstsz; 181 182 #define PO2(x) ((x & (x - 1)) == 0) 183 secsz = le16dec(bpb); 184 if (secsz < 512 || secsz > 4096 || !PO2(secsz)) 185 return (0); 186 clstsz = bpb[2]; 187 if (clstsz < 1 || clstsz > 128 || !PO2(clstsz)) 188 return (0); 189 #undef PO2 190 191 return (1); 192 } 193 194 static void 195 mbr_set_chs(struct g_part_table *table, uint32_t lba, u_char *cylp, u_char *hdp, 196 u_char *secp) 197 { 198 uint32_t cyl, hd, sec; 199 200 sec = lba % table->gpt_sectors + 1; 201 lba /= table->gpt_sectors; 202 hd = lba % table->gpt_heads; 203 lba /= table->gpt_heads; 204 cyl = lba; 205 if (cyl > 1023) 206 sec = hd = cyl = ~0; 207 208 *cylp = cyl & 0xff; 209 *hdp = hd & 0xff; 210 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 211 } 212 213 static int 214 mbr_align(struct g_part_table *basetable, uint32_t *start, uint32_t *size) 215 { 216 uint32_t sectors; 217 218 if (enforce_chs == 0) 219 return (0); 220 sectors = basetable->gpt_sectors; 221 if (*size < sectors) 222 return (EINVAL); 223 if (start != NULL && (*start % sectors)) { 224 *size += (*start % sectors) - sectors; 225 *start -= (*start % sectors) - sectors; 226 } 227 if (*size % sectors) 228 *size -= (*size % sectors); 229 if (*size < sectors) 230 return (EINVAL); 231 return (0); 232 } 233 234 static int 235 g_part_mbr_add(struct g_part_table *basetable, struct g_part_entry *baseentry, 236 struct g_part_parms *gpp) 237 { 238 struct g_part_mbr_entry *entry; 239 uint32_t start, size; 240 241 if (gpp->gpp_parms & G_PART_PARM_LABEL) 242 return (EINVAL); 243 244 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) 248 return (EINVAL); 249 if (baseentry->gpe_deleted) 250 bzero(&entry->ent, sizeof(entry->ent)); 251 252 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)); 263 } 264 265 static int 266 g_part_mbr_bootcode(struct g_part_table *basetable, struct g_part_parms *gpp) 267 { 268 struct g_part_mbr_table *table; 269 uint32_t dsn; 270 271 if (gpp->gpp_codesize != MBRSIZE) 272 return (ENODEV); 273 274 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; 279 return (0); 280 } 281 282 static int 283 g_part_mbr_create(struct g_part_table *basetable, struct g_part_parms *gpp) 284 { 285 struct g_provider *pp; 286 struct g_part_mbr_table *table; 287 288 pp = gpp->gpp_provider; 289 if (pp->sectorsize < MBRSIZE) 290 return (ENOSPC); 291 292 basetable->gpt_first = basetable->gpt_sectors; 293 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize, 294 UINT32_MAX) - 1; 295 296 table = (struct g_part_mbr_table *)basetable; 297 le16enc(table->mbr + DOSMAGICOFFSET, DOSMAGIC); 298 return (0); 299 } 300 301 static int 302 g_part_mbr_destroy(struct g_part_table *basetable, struct g_part_parms *gpp) 303 { 304 305 /* Wipe the first sector to clear the partitioning. */ 306 basetable->gpt_smhead |= 1; 307 return (0); 308 } 309 310 static void 311 g_part_mbr_dumpconf(struct g_part_table *basetable, struct g_part_entry *baseentry, 312 struct sbuf *sb, const char *indent) 313 { 314 struct g_part_mbr_entry *entry; 315 struct g_part_mbr_table *table; 316 uint32_t dsn; 317 318 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, 326 entry->ent.dp_typ); 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_cat(sb, "</efimedia>\n"); 334 } else { 335 /* confxml: scheme information */ 336 } 337 } 338 339 static int 340 g_part_mbr_dumpto(struct g_part_table *table, struct g_part_entry *baseentry) 341 { 342 struct g_part_mbr_entry *entry; 343 344 /* 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); 348 } 349 350 static int 351 g_part_mbr_modify(struct g_part_table *basetable, 352 struct g_part_entry *baseentry, struct g_part_parms *gpp) 353 { 354 struct g_part_mbr_entry *entry; 355 356 if (gpp->gpp_parms & G_PART_PARM_LABEL) 357 return (EINVAL); 358 359 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)); 362 return (0); 363 } 364 365 static int 366 g_part_mbr_resize(struct g_part_table *basetable, 367 struct g_part_entry *baseentry, struct g_part_parms *gpp) 368 { 369 struct g_part_mbr_entry *entry; 370 struct g_provider *pp; 371 uint32_t size; 372 373 if (baseentry == NULL) { 374 pp = LIST_FIRST(&basetable->gpt_gp->consumer)->provider; 375 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize, 376 UINT32_MAX) - 1; 377 return (0); 378 } 379 size = gpp->gpp_size; 380 if (mbr_align(basetable, NULL, &size) != 0) 381 return (EINVAL); 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) 386 return (EBUSY); 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); 392 return (0); 393 } 394 395 static const char * 396 g_part_mbr_name(struct g_part_table *table, struct g_part_entry *baseentry, 397 char *buf, size_t bufsz) 398 { 399 400 snprintf(buf, bufsz, "s%d", baseentry->gpe_index); 401 return (buf); 402 } 403 404 static int 405 g_part_mbr_probe(struct g_part_table *table, struct g_consumer *cp) 406 { 407 char psn[8]; 408 struct g_provider *pp; 409 u_char *buf, *p; 410 int error, index, res, sum; 411 uint16_t magic; 412 413 pp = cp->provider; 414 415 /* Sanity-check the provider. */ 416 if (pp->sectorsize < MBRSIZE || pp->mediasize < pp->sectorsize) 417 return (ENOSPC); 418 if (pp->sectorsize > 4096) 419 return (ENXIO); 420 421 /* 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) 424 return (ELOOP); 425 426 /* Check that there's a MBR. */ 427 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 428 if (buf == NULL) 429 return (error); 430 431 /* We goto out on mismatch. */ 432 res = ENXIO; 433 434 magic = le16dec(buf + DOSMAGICOFFSET); 435 if (magic != DOSMAGIC) 436 goto out; 437 438 for (index = 0; index < NDOSPART; index++) { 439 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 440 if (p[0] != 0 && p[0] != 0x80) 441 goto out; 442 } 443 444 /* 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. 451 */ 452 sum = 0; 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; 457 458 out: 459 g_free(buf); 460 return (res); 461 } 462 463 static int 464 g_part_mbr_read(struct g_part_table *basetable, struct g_consumer *cp) 465 { 466 struct dos_partition ent; 467 struct g_provider *pp; 468 struct g_part_mbr_table *table; 469 struct g_part_mbr_entry *entry; 470 u_char *buf, *p; 471 off_t chs, msize, first; 472 u_int sectors, heads; 473 int error, index; 474 475 pp = cp->provider; 476 table = (struct g_part_mbr_table *)basetable; 477 first = basetable->gpt_sectors; 478 msize = MIN(pp->mediasize / pp->sectorsize, UINT32_MAX); 479 480 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 481 if (buf == NULL) 482 return (error); 483 484 bcopy(buf, table->mbr, sizeof(table->mbr)); 485 for (index = NDOSPART - 1; index >= 0; index--) { 486 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 487 ent.dp_flag = p[0]; 488 ent.dp_shd = p[1]; 489 ent.dp_ssect = p[2]; 490 ent.dp_scyl = p[3]; 491 ent.dp_typ = p[4]; 492 ent.dp_ehd = p[5]; 493 ent.dp_esect = p[6]; 494 ent.dp_ecyl = p[7]; 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) 498 continue; 499 if (ent.dp_start == 0 || ent.dp_size == 0) 500 continue; 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); 505 if (chs != 0) { 506 basetable->gpt_sectors = sectors; 507 basetable->gpt_heads = heads; 508 } 509 } 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); 514 entry->ent = ent; 515 } 516 517 basetable->gpt_entries = NDOSPART; 518 basetable->gpt_first = basetable->gpt_sectors; 519 basetable->gpt_last = msize - 1; 520 521 if (first < basetable->gpt_first) 522 basetable->gpt_first = 1; 523 524 g_free(buf); 525 return (0); 526 } 527 528 static int 529 g_part_mbr_setunset(struct g_part_table *table, struct g_part_entry *baseentry, 530 const char *attrib, unsigned int set) 531 { 532 struct g_part_entry *iter; 533 struct g_part_mbr_entry *entry; 534 int changed; 535 536 if (baseentry == NULL) 537 return (ENODEV); 538 if (strcasecmp(attrib, "active") != 0) 539 return (EINVAL); 540 541 /* Only one entry can have the active attribute. */ 542 LIST_FOREACH(iter, &table->gpt_entry, gpe_entry) { 543 if (iter->gpe_deleted) 544 continue; 545 changed = 0; 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; 550 changed = 1; 551 } else if (!set && (entry->ent.dp_flag & 0x80)) { 552 entry->ent.dp_flag &= ~0x80; 553 changed = 1; 554 } 555 } else { 556 if (set && (entry->ent.dp_flag & 0x80)) { 557 entry->ent.dp_flag &= ~0x80; 558 changed = 1; 559 } 560 } 561 if (changed && !iter->gpe_created) 562 iter->gpe_modified = 1; 563 } 564 return (0); 565 } 566 567 static const char * 568 g_part_mbr_type(struct g_part_table *basetable, struct g_part_entry *baseentry, 569 char *buf, size_t bufsz) 570 { 571 struct g_part_mbr_entry *entry; 572 int i; 573 574 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)); 578 } 579 snprintf(buf, bufsz, "!%d", entry->ent.dp_typ); 580 return (buf); 581 } 582 583 static int 584 g_part_mbr_write(struct g_part_table *basetable, struct g_consumer *cp) 585 { 586 struct g_part_entry *baseentry; 587 struct g_part_mbr_entry *entry; 588 struct g_part_mbr_table *table; 589 u_char *p; 590 int error, index; 591 592 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); 609 } else 610 bzero(p, DOSPARTSIZE); 611 612 if (entry != NULL) 613 baseentry = LIST_NEXT(baseentry, gpe_entry); 614 } 615 616 error = g_write_data(cp, 0, table->mbr, cp->provider->sectorsize); 617 return (error); 618 } 619