1/*- 2 * Copyright (c) 2007, 2008 Marcel Moolenaar 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 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. 14 * 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. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: releng/11.0/sys/geom/part/g_part_mbr.c 298354 2016-04-20 16:19:44Z pfg $"); 29 30#include <sys/param.h> 31#include <sys/bio.h> 32#include <sys/diskmbr.h> 33#include <sys/endian.h> 34#include <sys/kernel.h> 35#include <sys/kobj.h> 36#include <sys/limits.h> 37#include <sys/lock.h> 38#include <sys/malloc.h> 39#include <sys/mutex.h> 40#include <sys/queue.h> 41#include <sys/sbuf.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> 47 48#include "g_part_if.h" 49 50FEATURE(geom_part_mbr, "GEOM partitioning class for MBR support"); 51 52SYSCTL_DECL(_kern_geom_part); 53static SYSCTL_NODE(_kern_geom_part, OID_AUTO, mbr, CTLFLAG_RW, 0, 54 "GEOM_PART_MBR Master Boot Record"); 55 56static u_int enforce_chs = 0; 57SYSCTL_UINT(_kern_geom_part_mbr, OID_AUTO, enforce_chs, 58 CTLFLAG_RWTUN, &enforce_chs, 0, "Enforce alignment to CHS addressing"); 59 60#define MBRSIZE 512 61 62struct g_part_mbr_table { 63 struct g_part_table base; 64 u_char mbr[MBRSIZE]; 65}; 66 67struct g_part_mbr_entry { 68 struct g_part_entry base; 69 struct dos_partition ent; 70}; 71 72static int g_part_mbr_add(struct g_part_table *, struct g_part_entry *, 73 struct g_part_parms *); 74static int g_part_mbr_bootcode(struct g_part_table *, struct g_part_parms *); 75static int g_part_mbr_create(struct g_part_table *, struct g_part_parms *); 76static int g_part_mbr_destroy(struct g_part_table *, struct g_part_parms *); 77static void g_part_mbr_dumpconf(struct g_part_table *, struct g_part_entry *, 78 struct sbuf *, const char *); 79static int g_part_mbr_dumpto(struct g_part_table *, struct g_part_entry *); 80static int g_part_mbr_modify(struct g_part_table *, struct g_part_entry *, 81 struct g_part_parms *); 82static const char *g_part_mbr_name(struct g_part_table *, struct g_part_entry *, 83 char *, size_t); 84static int g_part_mbr_probe(struct g_part_table *, struct g_consumer *); 85static int g_part_mbr_read(struct g_part_table *, struct g_consumer *); 86static int g_part_mbr_setunset(struct g_part_table *, struct g_part_entry *, 87 const char *, unsigned int); 88static const char *g_part_mbr_type(struct g_part_table *, struct g_part_entry *, 89 char *, size_t); 90static int g_part_mbr_write(struct g_part_table *, struct g_consumer *); 91static int g_part_mbr_resize(struct g_part_table *, struct g_part_entry *, 92 struct g_part_parms *); 93 94static 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), 109 { 0, 0 } 110}; 111 112static struct g_part_scheme g_part_mbr_scheme = { 113 "MBR", 114 g_part_mbr_methods, 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, 120}; 121G_PART_SCHEME_DECLARE(g_part_mbr); 122 123static struct g_part_mbr_alias { 124 u_char typ; 125 int 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 }, 144}; 145 146static int 147mbr_parse_type(const char *type, u_char *dp_typ) 148{ 149 const char *alias; 150 char *endp; 151 long lt; 152 int i; 153 154 if (type[0] == '!') { 155 lt = strtol(type + 1, &endp, 0); 156 if (type[1] == '\0' || *endp != '\0' || lt <= 0 || lt >= 256) 157 return (EINVAL); 158 *dp_typ = (u_char)lt; 159 return (0); 160 } 161 for (i = 0; i < nitems(mbr_alias_match); i++) { 162 alias = g_part_alias_name(mbr_alias_match[i].alias); 163 if (strcasecmp(type, alias) == 0) { 164 *dp_typ = mbr_alias_match[i].typ; 165 return (0); 166 } 167 } 168 return (EINVAL); 169} 170 171static int 172mbr_probe_bpb(u_char *bpb) 173{ 174 uint16_t secsz; 175 uint8_t clstsz; 176 177#define PO2(x) ((x & (x - 1)) == 0) 178 secsz = le16dec(bpb); 179 if (secsz < 512 || secsz > 4096 || !PO2(secsz)) 180 return (0); 181 clstsz = bpb[2]; 182 if (clstsz < 1 || clstsz > 128 || !PO2(clstsz)) 183 return (0); 184#undef PO2 185 186 return (1); 187} 188 189static void 190mbr_set_chs(struct g_part_table *table, uint32_t lba, u_char *cylp, u_char *hdp, 191 u_char *secp) 192{ 193 uint32_t cyl, hd, sec; 194 195 sec = lba % table->gpt_sectors + 1; 196 lba /= table->gpt_sectors; 197 hd = lba % table->gpt_heads; 198 lba /= table->gpt_heads; 199 cyl = lba; 200 if (cyl > 1023) 201 sec = hd = cyl = ~0; 202 203 *cylp = cyl & 0xff; 204 *hdp = hd & 0xff; 205 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 206} 207 208static int 209mbr_align(struct g_part_table *basetable, uint32_t *start, uint32_t *size) 210{ 211 uint32_t sectors; 212 213 if (enforce_chs == 0) 214 return (0); 215 sectors = basetable->gpt_sectors; 216 if (*size < sectors) 217 return (EINVAL); 218 if (start != NULL && (*start % sectors)) { 219 *size += (*start % sectors) - sectors; 220 *start -= (*start % sectors) - sectors; 221 } 222 if (*size % sectors) 223 *size -= (*size % sectors); 224 if (*size < sectors) 225 return (EINVAL); 226 return (0); 227} 228 229static int 230g_part_mbr_add(struct g_part_table *basetable, struct g_part_entry *baseentry, 231 struct g_part_parms *gpp) 232{ 233 struct g_part_mbr_entry *entry; 234 uint32_t start, size; 235 236 if (gpp->gpp_parms & G_PART_PARM_LABEL) 237 return (EINVAL); 238 239 entry = (struct g_part_mbr_entry *)baseentry; 240 start = gpp->gpp_start; 241 size = gpp->gpp_size; 242 if (mbr_align(basetable, &start, &size) != 0) 243 return (EINVAL); 244 if (baseentry->gpe_deleted) 245 bzero(&entry->ent, sizeof(entry->ent)); 246 247 KASSERT(baseentry->gpe_start <= start, ("%s", __func__)); 248 KASSERT(baseentry->gpe_end >= start + size - 1, ("%s", __func__)); 249 baseentry->gpe_start = start; 250 baseentry->gpe_end = start + size - 1; 251 entry->ent.dp_start = start; 252 entry->ent.dp_size = size; 253 mbr_set_chs(basetable, baseentry->gpe_start, &entry->ent.dp_scyl, 254 &entry->ent.dp_shd, &entry->ent.dp_ssect); 255 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl, 256 &entry->ent.dp_ehd, &entry->ent.dp_esect); 257 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 258} 259 260static int 261g_part_mbr_bootcode(struct g_part_table *basetable, struct g_part_parms *gpp) 262{ 263 struct g_part_mbr_table *table; 264 uint32_t dsn; 265 266 if (gpp->gpp_codesize != MBRSIZE) 267 return (ENODEV); 268 269 table = (struct g_part_mbr_table *)basetable; 270 dsn = *(uint32_t *)(table->mbr + DOSDSNOFF); 271 bcopy(gpp->gpp_codeptr, table->mbr, DOSPARTOFF); 272 if (dsn != 0) 273 *(uint32_t *)(table->mbr + DOSDSNOFF) = dsn; 274 return (0); 275} 276 277static int 278g_part_mbr_create(struct g_part_table *basetable, struct g_part_parms *gpp) 279{ 280 struct g_provider *pp; 281 struct g_part_mbr_table *table; 282 283 pp = gpp->gpp_provider; 284 if (pp->sectorsize < MBRSIZE) 285 return (ENOSPC); 286 287 basetable->gpt_first = basetable->gpt_sectors; 288 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize, 289 UINT32_MAX) - 1; 290 291 table = (struct g_part_mbr_table *)basetable; 292 le16enc(table->mbr + DOSMAGICOFFSET, DOSMAGIC); 293 return (0); 294} 295 296static int 297g_part_mbr_destroy(struct g_part_table *basetable, struct g_part_parms *gpp) 298{ 299 300 /* Wipe the first sector to clear the partitioning. */ 301 basetable->gpt_smhead |= 1; 302 return (0); 303} 304 305static void 306g_part_mbr_dumpconf(struct g_part_table *table, struct g_part_entry *baseentry, 307 struct sbuf *sb, const char *indent) 308{ 309 struct g_part_mbr_entry *entry; 310 311 entry = (struct g_part_mbr_entry *)baseentry; 312 if (indent == NULL) { 313 /* conftxt: libdisk compatibility */ 314 sbuf_printf(sb, " xs MBR xt %u", entry->ent.dp_typ); 315 } else if (entry != NULL) { 316 /* confxml: partition entry information */ 317 sbuf_printf(sb, "%s<rawtype>%u</rawtype>\n", indent, 318 entry->ent.dp_typ); 319 if (entry->ent.dp_flag & 0x80) 320 sbuf_printf(sb, "%s<attrib>active</attrib>\n", indent); 321 } else { 322 /* confxml: scheme information */ 323 } 324} 325 326static int 327g_part_mbr_dumpto(struct g_part_table *table, struct g_part_entry *baseentry) 328{ 329 struct g_part_mbr_entry *entry; 330 331 /* Allow dumping to a FreeBSD partition or Linux swap partition only. */ 332 entry = (struct g_part_mbr_entry *)baseentry; 333 return ((entry->ent.dp_typ == DOSPTYP_386BSD || 334 entry->ent.dp_typ == DOSPTYP_LINSWP) ? 1 : 0); 335} 336 337static int 338g_part_mbr_modify(struct g_part_table *basetable, 339 struct g_part_entry *baseentry, struct g_part_parms *gpp) 340{ 341 struct g_part_mbr_entry *entry; 342 343 if (gpp->gpp_parms & G_PART_PARM_LABEL) 344 return (EINVAL); 345 346 entry = (struct g_part_mbr_entry *)baseentry; 347 if (gpp->gpp_parms & G_PART_PARM_TYPE) 348 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 349 return (0); 350} 351 352static int 353g_part_mbr_resize(struct g_part_table *basetable, 354 struct g_part_entry *baseentry, struct g_part_parms *gpp) 355{ 356 struct g_part_mbr_entry *entry; 357 struct g_provider *pp; 358 uint32_t size; 359 360 if (baseentry == NULL) { 361 pp = LIST_FIRST(&basetable->gpt_gp->consumer)->provider; 362 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize, 363 UINT32_MAX) - 1; 364 return (0); 365 } 366 size = gpp->gpp_size; 367 if (mbr_align(basetable, NULL, &size) != 0) 368 return (EINVAL); 369 /* XXX: prevent unexpected shrinking. */ 370 pp = baseentry->gpe_pp; 371 if ((g_debugflags & 0x10) == 0 && size < gpp->gpp_size && 372 pp->mediasize / pp->sectorsize > size) 373 return (EBUSY); 374 entry = (struct g_part_mbr_entry *)baseentry; 375 baseentry->gpe_end = baseentry->gpe_start + size - 1; 376 entry->ent.dp_size = size; 377 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl, 378 &entry->ent.dp_ehd, &entry->ent.dp_esect); 379 return (0); 380} 381 382static const char * 383g_part_mbr_name(struct g_part_table *table, struct g_part_entry *baseentry, 384 char *buf, size_t bufsz) 385{ 386 387 snprintf(buf, bufsz, "s%d", baseentry->gpe_index); 388 return (buf); 389} 390 391static int 392g_part_mbr_probe(struct g_part_table *table, struct g_consumer *cp) 393{ 394 char psn[8]; 395 struct g_provider *pp; 396 u_char *buf, *p; 397 int error, index, res, sum; 398 uint16_t magic; 399 400 pp = cp->provider; 401 402 /* Sanity-check the provider. */ 403 if (pp->sectorsize < MBRSIZE || pp->mediasize < pp->sectorsize) 404 return (ENOSPC); 405 if (pp->sectorsize > 4096) 406 return (ENXIO); 407 408 /* We don't nest under an MBR (see EBR instead). */ 409 error = g_getattr("PART::scheme", cp, &psn); 410 if (error == 0 && strcmp(psn, g_part_mbr_scheme.name) == 0) 411 return (ELOOP); 412 413 /* Check that there's a MBR. */ 414 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 415 if (buf == NULL) 416 return (error); 417 418 /* We goto out on mismatch. */ 419 res = ENXIO; 420 421 magic = le16dec(buf + DOSMAGICOFFSET); 422 if (magic != DOSMAGIC) 423 goto out; 424 425 for (index = 0; index < NDOSPART; index++) { 426 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 427 if (p[0] != 0 && p[0] != 0x80) 428 goto out; 429 } 430 431 /* 432 * If the partition table does not consist of all zeroes, 433 * assume we have a MBR. If it's all zeroes, we could have 434 * a boot sector. For example, a boot sector that doesn't 435 * have boot code -- common on non-i386 hardware. In that 436 * case we check if we have a possible BPB. If so, then we 437 * assume we have a boot sector instead. 438 */ 439 sum = 0; 440 for (index = 0; index < NDOSPART * DOSPARTSIZE; index++) 441 sum += buf[DOSPARTOFF + index]; 442 if (sum != 0 || !mbr_probe_bpb(buf + 0x0b)) 443 res = G_PART_PROBE_PRI_NORM; 444 445 out: 446 g_free(buf); 447 return (res); 448} 449 450static int 451g_part_mbr_read(struct g_part_table *basetable, struct g_consumer *cp) 452{ 453 struct dos_partition ent; 454 struct g_provider *pp; 455 struct g_part_mbr_table *table; 456 struct g_part_mbr_entry *entry; 457 u_char *buf, *p; 458 off_t chs, msize, first; 459 u_int sectors, heads; 460 int error, index; 461 462 pp = cp->provider; 463 table = (struct g_part_mbr_table *)basetable; 464 first = basetable->gpt_sectors; 465 msize = MIN(pp->mediasize / pp->sectorsize, UINT32_MAX); 466 467 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 468 if (buf == NULL) 469 return (error); 470 471 bcopy(buf, table->mbr, sizeof(table->mbr)); 472 for (index = NDOSPART - 1; index >= 0; index--) { 473 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 474 ent.dp_flag = p[0]; 475 ent.dp_shd = p[1]; 476 ent.dp_ssect = p[2]; 477 ent.dp_scyl = p[3]; 478 ent.dp_typ = p[4]; 479 ent.dp_ehd = p[5]; 480 ent.dp_esect = p[6]; 481 ent.dp_ecyl = p[7]; 482 ent.dp_start = le32dec(p + 8); 483 ent.dp_size = le32dec(p + 12); 484 if (ent.dp_typ == 0 || ent.dp_typ == DOSPTYP_PMBR) 485 continue; 486 if (ent.dp_start == 0 || ent.dp_size == 0) 487 continue; 488 sectors = ent.dp_esect & 0x3f; 489 if (sectors > basetable->gpt_sectors && 490 !basetable->gpt_fixgeom) { 491 g_part_geometry_heads(msize, sectors, &chs, &heads); 492 if (chs != 0) { 493 basetable->gpt_sectors = sectors; 494 basetable->gpt_heads = heads; 495 } 496 } 497 if (ent.dp_start < first) 498 first = ent.dp_start; 499 entry = (struct g_part_mbr_entry *)g_part_new_entry(basetable, 500 index + 1, ent.dp_start, ent.dp_start + ent.dp_size - 1); 501 entry->ent = ent; 502 } 503 504 basetable->gpt_entries = NDOSPART; 505 basetable->gpt_first = basetable->gpt_sectors; 506 basetable->gpt_last = msize - 1; 507 508 if (first < basetable->gpt_first) 509 basetable->gpt_first = 1; 510 511 g_free(buf); 512 return (0); 513} 514 515static int 516g_part_mbr_setunset(struct g_part_table *table, struct g_part_entry *baseentry, 517 const char *attrib, unsigned int set) 518{ 519 struct g_part_entry *iter; 520 struct g_part_mbr_entry *entry; 521 int changed; 522 523 if (baseentry == NULL) 524 return (ENODEV); 525 if (strcasecmp(attrib, "active") != 0) 526 return (EINVAL); 527 528 /* Only one entry can have the active attribute. */ 529 LIST_FOREACH(iter, &table->gpt_entry, gpe_entry) { 530 if (iter->gpe_deleted) 531 continue; 532 changed = 0; 533 entry = (struct g_part_mbr_entry *)iter; 534 if (iter == baseentry) { 535 if (set && (entry->ent.dp_flag & 0x80) == 0) { 536 entry->ent.dp_flag |= 0x80; 537 changed = 1; 538 } else if (!set && (entry->ent.dp_flag & 0x80)) { 539 entry->ent.dp_flag &= ~0x80; 540 changed = 1; 541 } 542 } else { 543 if (set && (entry->ent.dp_flag & 0x80)) { 544 entry->ent.dp_flag &= ~0x80; 545 changed = 1; 546 } 547 } 548 if (changed && !iter->gpe_created) 549 iter->gpe_modified = 1; 550 } 551 return (0); 552} 553 554static const char * 555g_part_mbr_type(struct g_part_table *basetable, struct g_part_entry *baseentry, 556 char *buf, size_t bufsz) 557{ 558 struct g_part_mbr_entry *entry; 559 int i; 560 561 entry = (struct g_part_mbr_entry *)baseentry; 562 for (i = 0; i < nitems(mbr_alias_match); i++) { 563 if (mbr_alias_match[i].typ == entry->ent.dp_typ) 564 return (g_part_alias_name(mbr_alias_match[i].alias)); 565 } 566 snprintf(buf, bufsz, "!%d", entry->ent.dp_typ); 567 return (buf); 568} 569 570static int 571g_part_mbr_write(struct g_part_table *basetable, struct g_consumer *cp) 572{ 573 struct g_part_entry *baseentry; 574 struct g_part_mbr_entry *entry; 575 struct g_part_mbr_table *table; 576 u_char *p; 577 int error, index; 578 579 table = (struct g_part_mbr_table *)basetable; 580 baseentry = LIST_FIRST(&basetable->gpt_entry); 581 for (index = 1; index <= basetable->gpt_entries; index++) { 582 p = table->mbr + DOSPARTOFF + (index - 1) * DOSPARTSIZE; 583 entry = (baseentry != NULL && index == baseentry->gpe_index) 584 ? (struct g_part_mbr_entry *)baseentry : NULL; 585 if (entry != NULL && !baseentry->gpe_deleted) { 586 p[0] = entry->ent.dp_flag; 587 p[1] = entry->ent.dp_shd; 588 p[2] = entry->ent.dp_ssect; 589 p[3] = entry->ent.dp_scyl; 590 p[4] = entry->ent.dp_typ; 591 p[5] = entry->ent.dp_ehd; 592 p[6] = entry->ent.dp_esect; 593 p[7] = entry->ent.dp_ecyl; 594 le32enc(p + 8, entry->ent.dp_start); 595 le32enc(p + 12, entry->ent.dp_size); 596 } else 597 bzero(p, DOSPARTSIZE); 598 599 if (entry != NULL) 600 baseentry = LIST_NEXT(baseentry, gpe_entry); 601 } 602 603 error = g_write_data(cp, 0, table->mbr, cp->provider->sectorsize); 604 return (error); 605} 606