g_part_ebr.c revision 190849
1/*- 2 * Copyright (c) 2007-2009 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: head/sys/geom/part/g_part_ebr.c 190849 2009-04-08 16:18:16Z marcel $"); 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 <geom/geom.h> 44#include <geom/part/g_part.h> 45 46#include "g_part_if.h" 47 48#define EBRSIZE 512 49 50struct g_part_ebr_table { 51 struct g_part_table base; 52}; 53 54struct g_part_ebr_entry { 55 struct g_part_entry base; 56 struct dos_partition ent; 57 int alias; 58}; 59 60static int g_part_ebr_add(struct g_part_table *, struct g_part_entry *, 61 struct g_part_parms *); 62static int g_part_ebr_create(struct g_part_table *, struct g_part_parms *); 63static int g_part_ebr_destroy(struct g_part_table *, struct g_part_parms *); 64static int g_part_ebr_devalias(struct g_part_table *, struct g_part_entry *, 65 char *, size_t); 66static void g_part_ebr_dumpconf(struct g_part_table *, struct g_part_entry *, 67 struct sbuf *, const char *); 68static int g_part_ebr_dumpto(struct g_part_table *, struct g_part_entry *); 69static int g_part_ebr_modify(struct g_part_table *, struct g_part_entry *, 70 struct g_part_parms *); 71static const char *g_part_ebr_name(struct g_part_table *, struct g_part_entry *, 72 char *, size_t); 73static int g_part_ebr_precheck(struct g_part_table *, enum g_part_ctl, 74 struct g_part_parms *); 75static int g_part_ebr_probe(struct g_part_table *, struct g_consumer *); 76static int g_part_ebr_read(struct g_part_table *, struct g_consumer *); 77static int g_part_ebr_setunset(struct g_part_table *, struct g_part_entry *, 78 const char *, unsigned int); 79static const char *g_part_ebr_type(struct g_part_table *, struct g_part_entry *, 80 char *, size_t); 81static int g_part_ebr_write(struct g_part_table *, struct g_consumer *); 82 83static kobj_method_t g_part_ebr_methods[] = { 84 KOBJMETHOD(g_part_add, g_part_ebr_add), 85 KOBJMETHOD(g_part_create, g_part_ebr_create), 86 KOBJMETHOD(g_part_destroy, g_part_ebr_destroy), 87 KOBJMETHOD(g_part_devalias, g_part_ebr_devalias), 88 KOBJMETHOD(g_part_dumpconf, g_part_ebr_dumpconf), 89 KOBJMETHOD(g_part_dumpto, g_part_ebr_dumpto), 90 KOBJMETHOD(g_part_modify, g_part_ebr_modify), 91 KOBJMETHOD(g_part_name, g_part_ebr_name), 92 KOBJMETHOD(g_part_precheck, g_part_ebr_precheck), 93 KOBJMETHOD(g_part_probe, g_part_ebr_probe), 94 KOBJMETHOD(g_part_read, g_part_ebr_read), 95 KOBJMETHOD(g_part_setunset, g_part_ebr_setunset), 96 KOBJMETHOD(g_part_type, g_part_ebr_type), 97 KOBJMETHOD(g_part_write, g_part_ebr_write), 98 { 0, 0 } 99}; 100 101static struct g_part_scheme g_part_ebr_scheme = { 102 "EBR", 103 g_part_ebr_methods, 104 sizeof(struct g_part_ebr_table), 105 .gps_entrysz = sizeof(struct g_part_ebr_entry), 106 .gps_minent = 1, 107 .gps_maxent = INT_MAX, 108}; 109G_PART_SCHEME_DECLARE(g_part_ebr); 110 111static void ebr_set_chs(struct g_part_table *, uint32_t, u_char *, u_char *, 112 u_char *); 113 114static void 115ebr_entry_decode(const char *p, struct dos_partition *ent) 116{ 117 ent->dp_flag = p[0]; 118 ent->dp_shd = p[1]; 119 ent->dp_ssect = p[2]; 120 ent->dp_scyl = p[3]; 121 ent->dp_typ = p[4]; 122 ent->dp_ehd = p[5]; 123 ent->dp_esect = p[6]; 124 ent->dp_ecyl = p[7]; 125 ent->dp_start = le32dec(p + 8); 126 ent->dp_size = le32dec(p + 12); 127} 128 129static void 130ebr_entry_link(struct g_part_table *table, uint32_t start, uint32_t end, 131 u_char *buf) 132{ 133 134 buf[0] = 0 /* dp_flag */; 135 ebr_set_chs(table, start, &buf[3] /* dp_scyl */, &buf[1] /* dp_shd */, 136 &buf[2] /* dp_ssect */); 137 buf[4] = 5 /* dp_typ */; 138 ebr_set_chs(table, end, &buf[7] /* dp_ecyl */, &buf[5] /* dp_ehd */, 139 &buf[6] /* dp_esect */); 140 le32enc(buf + 8, start); 141 le32enc(buf + 12, end - start + 1); 142} 143 144static int 145ebr_parse_type(const char *type, u_char *dp_typ) 146{ 147 const char *alias; 148 char *endp; 149 long lt; 150 151 if (type[0] == '!') { 152 lt = strtol(type + 1, &endp, 0); 153 if (type[1] == '\0' || *endp != '\0' || lt <= 0 || lt >= 256) 154 return (EINVAL); 155 *dp_typ = (u_char)lt; 156 return (0); 157 } 158 alias = g_part_alias_name(G_PART_ALIAS_FREEBSD); 159 if (!strcasecmp(type, alias)) { 160 *dp_typ = DOSPTYP_386BSD; 161 return (0); 162 } 163 return (EINVAL); 164} 165 166static void 167ebr_set_chs(struct g_part_table *table, uint32_t lba, u_char *cylp, u_char *hdp, 168 u_char *secp) 169{ 170 uint32_t cyl, hd, sec; 171 172 sec = lba % table->gpt_sectors + 1; 173 lba /= table->gpt_sectors; 174 hd = lba % table->gpt_heads; 175 lba /= table->gpt_heads; 176 cyl = lba; 177 if (cyl > 1023) 178 sec = hd = cyl = ~0; 179 180 *cylp = cyl & 0xff; 181 *hdp = hd & 0xff; 182 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 183} 184 185static int 186g_part_ebr_add(struct g_part_table *basetable, struct g_part_entry *baseentry, 187 struct g_part_parms *gpp) 188{ 189 struct g_geom *gp; 190 struct g_provider *pp; 191 struct g_part_ebr_entry *entry; 192 uint32_t start, size, sectors; 193 194 if (gpp->gpp_parms & G_PART_PARM_LABEL) 195 return (EINVAL); 196 197 gp = basetable->gpt_gp; 198 pp = LIST_FIRST(&gp->consumer)->provider; 199 sectors = basetable->gpt_sectors; 200 201 entry = (struct g_part_ebr_entry *)baseentry; 202 203 start = gpp->gpp_start; 204 size = gpp->gpp_size; 205 if (size < 2 * sectors) 206 return (EINVAL); 207 if (start % sectors) { 208 size = size - sectors + (start % sectors); 209 start = start - (start % sectors) + sectors; 210 } 211 if (size % sectors) 212 size = size - (size % sectors); 213 if (size < 2 * sectors) 214 return (EINVAL); 215 216 if (baseentry->gpe_deleted) 217 bzero(&entry->ent, sizeof(entry->ent)); 218 219 KASSERT(baseentry->gpe_start <= start, (__func__)); 220 KASSERT(baseentry->gpe_end >= start + size - 1, (__func__)); 221 baseentry->gpe_index = (start / sectors) + 1; 222 baseentry->gpe_offset = (off_t)(start + sectors) * pp->sectorsize; 223 baseentry->gpe_start = start; 224 baseentry->gpe_end = start + size - 1; 225 entry->ent.dp_start = sectors; 226 entry->ent.dp_size = size - sectors; 227 ebr_set_chs(basetable, entry->ent.dp_start, &entry->ent.dp_scyl, 228 &entry->ent.dp_shd, &entry->ent.dp_ssect); 229 ebr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl, 230 &entry->ent.dp_ehd, &entry->ent.dp_esect); 231 return (ebr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 232} 233 234static int 235g_part_ebr_create(struct g_part_table *basetable, struct g_part_parms *gpp) 236{ 237 char psn[8]; 238 struct g_consumer *cp; 239 struct g_provider *pp; 240 uint32_t msize; 241 int error; 242 243 pp = gpp->gpp_provider; 244 245 if (pp->sectorsize < EBRSIZE) 246 return (ENOSPC); 247 if (pp->sectorsize > 4096) 248 return (ENXIO); 249 250 /* Check that we have a parent and that it's a MBR. */ 251 if (basetable->gpt_depth == 0) 252 return (ENXIO); 253 cp = LIST_FIRST(&pp->consumers); 254 error = g_getattr("PART::scheme", cp, &psn); 255 if (error) 256 return (error); 257 if (strcmp(psn, "MBR")) 258 return (ENXIO); 259 260 msize = MIN(pp->mediasize / pp->sectorsize, 0xffffffff); 261 msize -= msize % basetable->gpt_sectors; 262 basetable->gpt_first = 0; 263 basetable->gpt_last = msize - 1; 264 basetable->gpt_entries = msize / basetable->gpt_sectors; 265 return (0); 266} 267 268static int 269g_part_ebr_destroy(struct g_part_table *basetable, struct g_part_parms *gpp) 270{ 271 272 /* Wipe the first sector to clear the partitioning. */ 273 basetable->gpt_smhead |= 1; 274 return (0); 275} 276 277static int 278g_part_ebr_devalias(struct g_part_table *table, struct g_part_entry *baseentry, 279 char *buf, size_t bufsz) 280{ 281 struct g_part_ebr_entry *entry; 282 size_t len; 283 284 entry = (struct g_part_ebr_entry *)baseentry; 285 if (entry->alias == 0) 286 return (ENOENT); 287 288 len = strlcpy(buf, table->gpt_gp->name, bufsz); 289 if (len == 0) 290 return (EINVAL); 291 292 snprintf(buf + len - 1, bufsz - len, "%d", entry->alias); 293 return (0); 294} 295 296static void 297g_part_ebr_dumpconf(struct g_part_table *table, struct g_part_entry *baseentry, 298 struct sbuf *sb, const char *indent) 299{ 300 struct g_part_ebr_entry *entry; 301 302 entry = (struct g_part_ebr_entry *)baseentry; 303 if (indent == NULL) { 304 /* conftxt: libdisk compatibility */ 305 sbuf_printf(sb, " xs MBREXT xt %u", entry->ent.dp_typ); 306 } else if (entry != NULL) { 307 /* confxml: partition entry information */ 308 sbuf_printf(sb, "%s<rawtype>%u</rawtype>\n", indent, 309 entry->ent.dp_typ); 310 if (entry->ent.dp_flag & 0x80) 311 sbuf_printf(sb, "%s<attrib>active</attrib>\n", indent); 312 } else { 313 /* confxml: scheme information */ 314 } 315} 316 317static int 318g_part_ebr_dumpto(struct g_part_table *table, struct g_part_entry *baseentry) 319{ 320 struct g_part_ebr_entry *entry; 321 322 /* Allow dumping to a FreeBSD partition only. */ 323 entry = (struct g_part_ebr_entry *)baseentry; 324 return ((entry->ent.dp_typ == DOSPTYP_386BSD) ? 1 : 0); 325} 326 327static int 328g_part_ebr_modify(struct g_part_table *basetable, 329 struct g_part_entry *baseentry, struct g_part_parms *gpp) 330{ 331 struct g_part_ebr_entry *entry; 332 333 if (gpp->gpp_parms & G_PART_PARM_LABEL) 334 return (EINVAL); 335 336 entry = (struct g_part_ebr_entry *)baseentry; 337 if (gpp->gpp_parms & G_PART_PARM_TYPE) 338 return (ebr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 339 return (0); 340} 341 342static const char * 343g_part_ebr_name(struct g_part_table *table, struct g_part_entry *entry, 344 char *buf, size_t bufsz) 345{ 346 347 snprintf(buf, bufsz, "+%08u", entry->gpe_index); 348 return (buf); 349} 350 351static int 352g_part_ebr_precheck(struct g_part_table *table, enum g_part_ctl req, 353 struct g_part_parms *gpp) 354{ 355 356 /* 357 * The index is a function of the start of the partition. 358 * This is not something the user can override, nor is it 359 * something the common code will do right. We can set the 360 * index now so that we get what we need. 361 */ 362 if (req == G_PART_CTL_ADD) 363 gpp->gpp_index = (gpp->gpp_start / table->gpt_sectors) + 1; 364 365 return (0); 366} 367 368static int 369g_part_ebr_probe(struct g_part_table *table, struct g_consumer *cp) 370{ 371 char psn[8]; 372 struct g_provider *pp; 373 u_char *buf, *p; 374 int error, index, res, sum; 375 uint16_t magic; 376 377 pp = cp->provider; 378 379 /* Sanity-check the provider. */ 380 if (pp->sectorsize < EBRSIZE || pp->mediasize < pp->sectorsize) 381 return (ENOSPC); 382 if (pp->sectorsize > 4096) 383 return (ENXIO); 384 385 /* Check that we have a parent and that it's a MBR. */ 386 if (table->gpt_depth == 0) 387 return (ENXIO); 388 error = g_getattr("PART::scheme", cp, &psn); 389 if (error) 390 return (error); 391 if (strcmp(psn, "MBR")) 392 return (ENXIO); 393 394 /* Check that there's a EBR. */ 395 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 396 if (buf == NULL) 397 return (error); 398 399 /* We goto out on mismatch. */ 400 res = ENXIO; 401 402 magic = le16dec(buf + DOSMAGICOFFSET); 403 if (magic != DOSMAGIC) 404 goto out; 405 406 /* 407 * The sector is all zeroes, except for the partition entries 408 * and some signatures or disk serial number. Those can be 409 * found in the 9 bytes immediately in front of the partition 410 * table. 411 */ 412 sum = 0; 413 for (index = 0; index < DOSPARTOFF - 9; index++) 414 sum += buf[index]; 415 if (sum != 0) 416 goto out; 417 418 for (index = 0; index < NDOSPART; index++) { 419 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 420 if (p[0] != 0 && p[0] != 0x80) 421 goto out; 422 if (index < 2) 423 continue; 424 /* The 3rd & 4th entries are always zero. */ 425 if ((le64dec(p+0) + le64dec(p+8)) != 0) 426 goto out; 427 } 428 429 res = G_PART_PROBE_PRI_NORM; 430 431 out: 432 g_free(buf); 433 return (res); 434} 435 436static int 437g_part_ebr_read(struct g_part_table *basetable, struct g_consumer *cp) 438{ 439 struct dos_partition ent[2]; 440 struct g_provider *pp; 441 struct g_part_entry *baseentry; 442 struct g_part_ebr_table *table; 443 struct g_part_ebr_entry *entry; 444 u_char *buf; 445 off_t ofs, msize; 446 u_int lba; 447 int alias, error, index; 448 449 pp = cp->provider; 450 table = (struct g_part_ebr_table *)basetable; 451 msize = pp->mediasize / pp->sectorsize; 452 453 alias = 5; 454 lba = 0; 455 while (1) { 456 ofs = (off_t)lba * pp->sectorsize; 457 buf = g_read_data(cp, ofs, pp->sectorsize, &error); 458 if (buf == NULL) 459 return (error); 460 461 ebr_entry_decode(buf + DOSPARTOFF + 0 * DOSPARTSIZE, ent + 0); 462 ebr_entry_decode(buf + DOSPARTOFF + 1 * DOSPARTSIZE, ent + 1); 463 g_free(buf); 464 465 if (ent[0].dp_typ == 0) 466 break; 467 468 if (ent[0].dp_typ == 5 && ent[1].dp_typ == 0) { 469 lba = ent[0].dp_start; 470 continue; 471 } 472 473 index = (lba / basetable->gpt_sectors) + 1; 474 baseentry = (struct g_part_entry *)g_part_new_entry(basetable, 475 index, lba, lba + ent[0].dp_start + ent[0].dp_size - 1); 476 baseentry->gpe_offset = (off_t)(lba + ent[0].dp_start) * 477 pp->sectorsize; 478 entry = (struct g_part_ebr_entry *)baseentry; 479 entry->ent = ent[0]; 480 entry->alias = alias++; 481 482 if (ent[1].dp_typ == 0) 483 break; 484 485 lba = ent[1].dp_start; 486 } 487 488 basetable->gpt_entries = msize / basetable->gpt_sectors; 489 basetable->gpt_first = 0; 490 basetable->gpt_last = msize - (msize % basetable->gpt_sectors) - 1; 491 return (0); 492} 493 494static int 495g_part_ebr_setunset(struct g_part_table *table, struct g_part_entry *baseentry, 496 const char *attrib, unsigned int set) 497{ 498 struct g_part_entry *iter; 499 struct g_part_ebr_entry *entry; 500 int changed; 501 502 if (strcasecmp(attrib, "active") != 0) 503 return (EINVAL); 504 505 /* Only one entry can have the active attribute. */ 506 LIST_FOREACH(iter, &table->gpt_entry, gpe_entry) { 507 if (iter->gpe_deleted) 508 continue; 509 changed = 0; 510 entry = (struct g_part_ebr_entry *)iter; 511 if (iter == baseentry) { 512 if (set && (entry->ent.dp_flag & 0x80) == 0) { 513 entry->ent.dp_flag |= 0x80; 514 changed = 1; 515 } else if (!set && (entry->ent.dp_flag & 0x80)) { 516 entry->ent.dp_flag &= ~0x80; 517 changed = 1; 518 } 519 } else { 520 if (set && (entry->ent.dp_flag & 0x80)) { 521 entry->ent.dp_flag &= ~0x80; 522 changed = 1; 523 } 524 } 525 if (changed && !iter->gpe_created) 526 iter->gpe_modified = 1; 527 } 528 return (0); 529} 530 531static const char * 532g_part_ebr_type(struct g_part_table *basetable, struct g_part_entry *baseentry, 533 char *buf, size_t bufsz) 534{ 535 struct g_part_ebr_entry *entry; 536 int type; 537 538 entry = (struct g_part_ebr_entry *)baseentry; 539 type = entry->ent.dp_typ; 540 if (type == DOSPTYP_386BSD) 541 return (g_part_alias_name(G_PART_ALIAS_FREEBSD)); 542 snprintf(buf, bufsz, "!%d", type); 543 return (buf); 544} 545 546static int 547g_part_ebr_write(struct g_part_table *basetable, struct g_consumer *cp) 548{ 549 struct g_provider *pp; 550 struct g_part_entry *baseentry, *next; 551 struct g_part_ebr_entry *entry; 552 u_char *buf; 553 u_char *p; 554 int error; 555 556 pp = cp->provider; 557 buf = g_malloc(pp->sectorsize, M_WAITOK | M_ZERO); 558 le16enc(buf + DOSMAGICOFFSET, DOSMAGIC); 559 560 baseentry = LIST_FIRST(&basetable->gpt_entry); 561 while (baseentry != NULL && baseentry->gpe_deleted) 562 baseentry = LIST_NEXT(baseentry, gpe_entry); 563 564 /* Wipe-out the the first EBR when there are no slices. */ 565 if (baseentry == NULL) { 566 error = g_write_data(cp, 0, buf, pp->sectorsize); 567 goto out; 568 } 569 570 /* 571 * If the first partition is not in LBA 0, we need to 572 * put a "link" EBR in LBA 0. 573 */ 574 if (baseentry->gpe_start != 0) { 575 ebr_entry_link(basetable, (uint32_t)baseentry->gpe_start, 576 (uint32_t)baseentry->gpe_end, buf + DOSPARTOFF); 577 error = g_write_data(cp, 0, buf, pp->sectorsize); 578 if (error) 579 goto out; 580 } 581 582 do { 583 entry = (struct g_part_ebr_entry *)baseentry; 584 585 p = buf + DOSPARTOFF; 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); 596 597 next = LIST_NEXT(baseentry, gpe_entry); 598 while (next != NULL && next->gpe_deleted) 599 next = LIST_NEXT(next, gpe_entry); 600 601 p += DOSPARTSIZE; 602 if (next != NULL) 603 ebr_entry_link(basetable, (uint32_t)next->gpe_start, 604 (uint32_t)next->gpe_end, p); 605 else 606 bzero(p, DOSPARTSIZE); 607 608 error = g_write_data(cp, baseentry->gpe_start * pp->sectorsize, 609 buf, pp->sectorsize); 610 611 baseentry = next; 612 } while (!error && baseentry != NULL); 613 614 out: 615 g_free(buf); 616 return (error); 617} 618