1// SPDX-License-Identifier: GPL-2.0 2/* 3 * fs/partitions/msdos.c 4 * 5 * Code extracted from drivers/block/genhd.c 6 * Copyright (C) 1991-1998 Linus Torvalds 7 * 8 * Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug 9 * in the early extended-partition checks and added DM partitions 10 * 11 * Support for DiskManager v6.0x added by Mark Lord, 12 * with information provided by OnTrack. This now works for linux fdisk 13 * and LILO, as well as loadlin and bootln. Note that disks other than 14 * /dev/hda *must* have a "DOS" type 0x51 partition in the first slot (hda1). 15 * 16 * More flexible handling of extended partitions - aeb, 950831 17 * 18 * Check partition table on IDE disks for common CHS translations 19 * 20 * Re-organised Feb 1998 Russell King 21 * 22 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il> 23 * updated by Marc Espie <Marc.Espie@openbsd.org> 24 * 25 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl> 26 * and Krzysztof G. Baranowski <kgb@knm.org.pl> 27 */ 28#include <linux/msdos_fs.h> 29#include <linux/msdos_partition.h> 30 31#include "check.h" 32#include "efi.h" 33 34/* 35 * Many architectures don't like unaligned accesses, while 36 * the nr_sects and start_sect partition table entries are 37 * at a 2 (mod 4) address. 38 */ 39#include <asm/unaligned.h> 40 41static inline sector_t nr_sects(struct msdos_partition *p) 42{ 43 return (sector_t)get_unaligned_le32(&p->nr_sects); 44} 45 46static inline sector_t start_sect(struct msdos_partition *p) 47{ 48 return (sector_t)get_unaligned_le32(&p->start_sect); 49} 50 51static inline int is_extended_partition(struct msdos_partition *p) 52{ 53 return (p->sys_ind == DOS_EXTENDED_PARTITION || 54 p->sys_ind == WIN98_EXTENDED_PARTITION || 55 p->sys_ind == LINUX_EXTENDED_PARTITION); 56} 57 58#define MSDOS_LABEL_MAGIC1 0x55 59#define MSDOS_LABEL_MAGIC2 0xAA 60 61static inline int 62msdos_magic_present(unsigned char *p) 63{ 64 return (p[0] == MSDOS_LABEL_MAGIC1 && p[1] == MSDOS_LABEL_MAGIC2); 65} 66 67/* Value is EBCDIC 'IBMA' */ 68#define AIX_LABEL_MAGIC1 0xC9 69#define AIX_LABEL_MAGIC2 0xC2 70#define AIX_LABEL_MAGIC3 0xD4 71#define AIX_LABEL_MAGIC4 0xC1 72static int aix_magic_present(struct parsed_partitions *state, unsigned char *p) 73{ 74 struct msdos_partition *pt = (struct msdos_partition *) (p + 0x1be); 75 Sector sect; 76 unsigned char *d; 77 int slot, ret = 0; 78 79 if (!(p[0] == AIX_LABEL_MAGIC1 && 80 p[1] == AIX_LABEL_MAGIC2 && 81 p[2] == AIX_LABEL_MAGIC3 && 82 p[3] == AIX_LABEL_MAGIC4)) 83 return 0; 84 85 /* 86 * Assume the partition table is valid if Linux partitions exists. 87 * Note that old Solaris/x86 partitions use the same indicator as 88 * Linux swap partitions, so we consider that a Linux partition as 89 * well. 90 */ 91 for (slot = 1; slot <= 4; slot++, pt++) { 92 if (pt->sys_ind == SOLARIS_X86_PARTITION || 93 pt->sys_ind == LINUX_RAID_PARTITION || 94 pt->sys_ind == LINUX_DATA_PARTITION || 95 pt->sys_ind == LINUX_LVM_PARTITION || 96 is_extended_partition(pt)) 97 return 0; 98 } 99 d = read_part_sector(state, 7, §); 100 if (d) { 101 if (d[0] == '_' && d[1] == 'L' && d[2] == 'V' && d[3] == 'M') 102 ret = 1; 103 put_dev_sector(sect); 104 } 105 return ret; 106} 107 108static void set_info(struct parsed_partitions *state, int slot, 109 u32 disksig) 110{ 111 struct partition_meta_info *info = &state->parts[slot].info; 112 113 snprintf(info->uuid, sizeof(info->uuid), "%08x-%02x", disksig, 114 slot); 115 info->volname[0] = 0; 116 state->parts[slot].has_info = true; 117} 118 119/* 120 * Create devices for each logical partition in an extended partition. 121 * The logical partitions form a linked list, with each entry being 122 * a partition table with two entries. The first entry 123 * is the real data partition (with a start relative to the partition 124 * table start). The second is a pointer to the next logical partition 125 * (with a start relative to the entire extended partition). 126 * We do not create a Linux partition for the partition tables, but 127 * only for the actual data partitions. 128 */ 129 130static void parse_extended(struct parsed_partitions *state, 131 sector_t first_sector, sector_t first_size, 132 u32 disksig) 133{ 134 struct msdos_partition *p; 135 Sector sect; 136 unsigned char *data; 137 sector_t this_sector, this_size; 138 sector_t sector_size; 139 int loopct = 0; /* number of links followed 140 without finding a data partition */ 141 int i; 142 143 sector_size = queue_logical_block_size(state->disk->queue) / 512; 144 this_sector = first_sector; 145 this_size = first_size; 146 147 while (1) { 148 if (++loopct > 100) 149 return; 150 if (state->next == state->limit) 151 return; 152 data = read_part_sector(state, this_sector, §); 153 if (!data) 154 return; 155 156 if (!msdos_magic_present(data + 510)) 157 goto done; 158 159 p = (struct msdos_partition *) (data + 0x1be); 160 161 /* 162 * Usually, the first entry is the real data partition, 163 * the 2nd entry is the next extended partition, or empty, 164 * and the 3rd and 4th entries are unused. 165 * However, DRDOS sometimes has the extended partition as 166 * the first entry (when the data partition is empty), 167 * and OS/2 seems to use all four entries. 168 */ 169 170 /* 171 * First process the data partition(s) 172 */ 173 for (i = 0; i < 4; i++, p++) { 174 sector_t offs, size, next; 175 176 if (!nr_sects(p) || is_extended_partition(p)) 177 continue; 178 179 /* Check the 3rd and 4th entries - 180 these sometimes contain random garbage */ 181 offs = start_sect(p)*sector_size; 182 size = nr_sects(p)*sector_size; 183 next = this_sector + offs; 184 if (i >= 2) { 185 if (offs + size > this_size) 186 continue; 187 if (next < first_sector) 188 continue; 189 if (next + size > first_sector + first_size) 190 continue; 191 } 192 193 put_partition(state, state->next, next, size); 194 set_info(state, state->next, disksig); 195 if (p->sys_ind == LINUX_RAID_PARTITION) 196 state->parts[state->next].flags = ADDPART_FLAG_RAID; 197 loopct = 0; 198 if (++state->next == state->limit) 199 goto done; 200 } 201 /* 202 * Next, process the (first) extended partition, if present. 203 * (So far, there seems to be no reason to make 204 * parse_extended() recursive and allow a tree 205 * of extended partitions.) 206 * It should be a link to the next logical partition. 207 */ 208 p -= 4; 209 for (i = 0; i < 4; i++, p++) 210 if (nr_sects(p) && is_extended_partition(p)) 211 break; 212 if (i == 4) 213 goto done; /* nothing left to do */ 214 215 this_sector = first_sector + start_sect(p) * sector_size; 216 this_size = nr_sects(p) * sector_size; 217 put_dev_sector(sect); 218 } 219done: 220 put_dev_sector(sect); 221} 222 223#define SOLARIS_X86_NUMSLICE 16 224#define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL) 225 226struct solaris_x86_slice { 227 __le16 s_tag; /* ID tag of partition */ 228 __le16 s_flag; /* permission flags */ 229 __le32 s_start; /* start sector no of partition */ 230 __le32 s_size; /* # of blocks in partition */ 231}; 232 233struct solaris_x86_vtoc { 234 unsigned int v_bootinfo[3]; /* info needed by mboot */ 235 __le32 v_sanity; /* to verify vtoc sanity */ 236 __le32 v_version; /* layout version */ 237 char v_volume[8]; /* volume name */ 238 __le16 v_sectorsz; /* sector size in bytes */ 239 __le16 v_nparts; /* number of partitions */ 240 unsigned int v_reserved[10]; /* free space */ 241 struct solaris_x86_slice 242 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */ 243 unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp */ 244 char v_asciilabel[128]; /* for compatibility */ 245}; 246 247/* james@bpgc.com: Solaris has a nasty indicator: 0x82 which also 248 indicates linux swap. Be careful before believing this is Solaris. */ 249 250static void parse_solaris_x86(struct parsed_partitions *state, 251 sector_t offset, sector_t size, int origin) 252{ 253#ifdef CONFIG_SOLARIS_X86_PARTITION 254 Sector sect; 255 struct solaris_x86_vtoc *v; 256 int i; 257 short max_nparts; 258 259 v = read_part_sector(state, offset + 1, §); 260 if (!v) 261 return; 262 if (le32_to_cpu(v->v_sanity) != SOLARIS_X86_VTOC_SANE) { 263 put_dev_sector(sect); 264 return; 265 } 266 { 267 char tmp[1 + BDEVNAME_SIZE + 10 + 11 + 1]; 268 269 snprintf(tmp, sizeof(tmp), " %s%d: <solaris:", state->name, origin); 270 strlcat(state->pp_buf, tmp, PAGE_SIZE); 271 } 272 if (le32_to_cpu(v->v_version) != 1) { 273 char tmp[64]; 274 275 snprintf(tmp, sizeof(tmp), " cannot handle version %d vtoc>\n", 276 le32_to_cpu(v->v_version)); 277 strlcat(state->pp_buf, tmp, PAGE_SIZE); 278 put_dev_sector(sect); 279 return; 280 } 281 /* Ensure we can handle previous case of VTOC with 8 entries gracefully */ 282 max_nparts = le16_to_cpu(v->v_nparts) > 8 ? SOLARIS_X86_NUMSLICE : 8; 283 for (i = 0; i < max_nparts && state->next < state->limit; i++) { 284 struct solaris_x86_slice *s = &v->v_slice[i]; 285 char tmp[3 + 10 + 1 + 1]; 286 287 if (s->s_size == 0) 288 continue; 289 snprintf(tmp, sizeof(tmp), " [s%d]", i); 290 strlcat(state->pp_buf, tmp, PAGE_SIZE); 291 /* solaris partitions are relative to current MS-DOS 292 * one; must add the offset of the current partition */ 293 put_partition(state, state->next++, 294 le32_to_cpu(s->s_start)+offset, 295 le32_to_cpu(s->s_size)); 296 } 297 put_dev_sector(sect); 298 strlcat(state->pp_buf, " >\n", PAGE_SIZE); 299#endif 300} 301 302/* check against BSD src/sys/sys/disklabel.h for consistency */ 303#define BSD_DISKMAGIC (0x82564557UL) /* The disk magic number */ 304#define BSD_MAXPARTITIONS 16 305#define OPENBSD_MAXPARTITIONS 16 306#define BSD_FS_UNUSED 0 /* disklabel unused partition entry ID */ 307struct bsd_disklabel { 308 __le32 d_magic; /* the magic number */ 309 __s16 d_type; /* drive type */ 310 __s16 d_subtype; /* controller/d_type specific */ 311 char d_typename[16]; /* type name, e.g. "eagle" */ 312 char d_packname[16]; /* pack identifier */ 313 __u32 d_secsize; /* # of bytes per sector */ 314 __u32 d_nsectors; /* # of data sectors per track */ 315 __u32 d_ntracks; /* # of tracks per cylinder */ 316 __u32 d_ncylinders; /* # of data cylinders per unit */ 317 __u32 d_secpercyl; /* # of data sectors per cylinder */ 318 __u32 d_secperunit; /* # of data sectors per unit */ 319 __u16 d_sparespertrack; /* # of spare sectors per track */ 320 __u16 d_sparespercyl; /* # of spare sectors per cylinder */ 321 __u32 d_acylinders; /* # of alt. cylinders per unit */ 322 __u16 d_rpm; /* rotational speed */ 323 __u16 d_interleave; /* hardware sector interleave */ 324 __u16 d_trackskew; /* sector 0 skew, per track */ 325 __u16 d_cylskew; /* sector 0 skew, per cylinder */ 326 __u32 d_headswitch; /* head switch time, usec */ 327 __u32 d_trkseek; /* track-to-track seek, usec */ 328 __u32 d_flags; /* generic flags */ 329#define NDDATA 5 330 __u32 d_drivedata[NDDATA]; /* drive-type specific information */ 331#define NSPARE 5 332 __u32 d_spare[NSPARE]; /* reserved for future use */ 333 __le32 d_magic2; /* the magic number (again) */ 334 __le16 d_checksum; /* xor of data incl. partitions */ 335 336 /* filesystem and partition information: */ 337 __le16 d_npartitions; /* number of partitions in following */ 338 __le32 d_bbsize; /* size of boot area at sn0, bytes */ 339 __le32 d_sbsize; /* max size of fs superblock, bytes */ 340 struct bsd_partition { /* the partition table */ 341 __le32 p_size; /* number of sectors in partition */ 342 __le32 p_offset; /* starting sector */ 343 __le32 p_fsize; /* filesystem basic fragment size */ 344 __u8 p_fstype; /* filesystem type, see below */ 345 __u8 p_frag; /* filesystem fragments per block */ 346 __le16 p_cpg; /* filesystem cylinders per group */ 347 } d_partitions[BSD_MAXPARTITIONS]; /* actually may be more */ 348}; 349 350#if defined(CONFIG_BSD_DISKLABEL) 351/* 352 * Create devices for BSD partitions listed in a disklabel, under a 353 * dos-like partition. See parse_extended() for more information. 354 */ 355static void parse_bsd(struct parsed_partitions *state, 356 sector_t offset, sector_t size, int origin, char *flavour, 357 int max_partitions) 358{ 359 Sector sect; 360 struct bsd_disklabel *l; 361 struct bsd_partition *p; 362 char tmp[64]; 363 364 l = read_part_sector(state, offset + 1, §); 365 if (!l) 366 return; 367 if (le32_to_cpu(l->d_magic) != BSD_DISKMAGIC) { 368 put_dev_sector(sect); 369 return; 370 } 371 372 snprintf(tmp, sizeof(tmp), " %s%d: <%s:", state->name, origin, flavour); 373 strlcat(state->pp_buf, tmp, PAGE_SIZE); 374 375 if (le16_to_cpu(l->d_npartitions) < max_partitions) 376 max_partitions = le16_to_cpu(l->d_npartitions); 377 for (p = l->d_partitions; p - l->d_partitions < max_partitions; p++) { 378 sector_t bsd_start, bsd_size; 379 380 if (state->next == state->limit) 381 break; 382 if (p->p_fstype == BSD_FS_UNUSED) 383 continue; 384 bsd_start = le32_to_cpu(p->p_offset); 385 bsd_size = le32_to_cpu(p->p_size); 386 /* FreeBSD has relative offset if C partition offset is zero */ 387 if (memcmp(flavour, "bsd\0", 4) == 0 && 388 le32_to_cpu(l->d_partitions[2].p_offset) == 0) 389 bsd_start += offset; 390 if (offset == bsd_start && size == bsd_size) 391 /* full parent partition, we have it already */ 392 continue; 393 if (offset > bsd_start || offset+size < bsd_start+bsd_size) { 394 strlcat(state->pp_buf, "bad subpartition - ignored\n", PAGE_SIZE); 395 continue; 396 } 397 put_partition(state, state->next++, bsd_start, bsd_size); 398 } 399 put_dev_sector(sect); 400 if (le16_to_cpu(l->d_npartitions) > max_partitions) { 401 snprintf(tmp, sizeof(tmp), " (ignored %d more)", 402 le16_to_cpu(l->d_npartitions) - max_partitions); 403 strlcat(state->pp_buf, tmp, PAGE_SIZE); 404 } 405 strlcat(state->pp_buf, " >\n", PAGE_SIZE); 406} 407#endif 408 409static void parse_freebsd(struct parsed_partitions *state, 410 sector_t offset, sector_t size, int origin) 411{ 412#ifdef CONFIG_BSD_DISKLABEL 413 parse_bsd(state, offset, size, origin, "bsd", BSD_MAXPARTITIONS); 414#endif 415} 416 417static void parse_netbsd(struct parsed_partitions *state, 418 sector_t offset, sector_t size, int origin) 419{ 420#ifdef CONFIG_BSD_DISKLABEL 421 parse_bsd(state, offset, size, origin, "netbsd", BSD_MAXPARTITIONS); 422#endif 423} 424 425static void parse_openbsd(struct parsed_partitions *state, 426 sector_t offset, sector_t size, int origin) 427{ 428#ifdef CONFIG_BSD_DISKLABEL 429 parse_bsd(state, offset, size, origin, "openbsd", 430 OPENBSD_MAXPARTITIONS); 431#endif 432} 433 434#define UNIXWARE_DISKMAGIC (0xCA5E600DUL) /* The disk magic number */ 435#define UNIXWARE_DISKMAGIC2 (0x600DDEEEUL) /* The slice table magic nr */ 436#define UNIXWARE_NUMSLICE 16 437#define UNIXWARE_FS_UNUSED 0 /* Unused slice entry ID */ 438 439struct unixware_slice { 440 __le16 s_label; /* label */ 441 __le16 s_flags; /* permission flags */ 442 __le32 start_sect; /* starting sector */ 443 __le32 nr_sects; /* number of sectors in slice */ 444}; 445 446struct unixware_disklabel { 447 __le32 d_type; /* drive type */ 448 __le32 d_magic; /* the magic number */ 449 __le32 d_version; /* version number */ 450 char d_serial[12]; /* serial number of the device */ 451 __le32 d_ncylinders; /* # of data cylinders per device */ 452 __le32 d_ntracks; /* # of tracks per cylinder */ 453 __le32 d_nsectors; /* # of data sectors per track */ 454 __le32 d_secsize; /* # of bytes per sector */ 455 __le32 d_part_start; /* # of first sector of this partition*/ 456 __le32 d_unknown1[12]; /* ? */ 457 __le32 d_alt_tbl; /* byte offset of alternate table */ 458 __le32 d_alt_len; /* byte length of alternate table */ 459 __le32 d_phys_cyl; /* # of physical cylinders per device */ 460 __le32 d_phys_trk; /* # of physical tracks per cylinder */ 461 __le32 d_phys_sec; /* # of physical sectors per track */ 462 __le32 d_phys_bytes; /* # of physical bytes per sector */ 463 __le32 d_unknown2; /* ? */ 464 __le32 d_unknown3; /* ? */ 465 __le32 d_pad[8]; /* pad */ 466 467 struct unixware_vtoc { 468 __le32 v_magic; /* the magic number */ 469 __le32 v_version; /* version number */ 470 char v_name[8]; /* volume name */ 471 __le16 v_nslices; /* # of slices */ 472 __le16 v_unknown1; /* ? */ 473 __le32 v_reserved[10]; /* reserved */ 474 struct unixware_slice 475 v_slice[UNIXWARE_NUMSLICE]; /* slice headers */ 476 } vtoc; 477}; /* 408 */ 478 479/* 480 * Create devices for Unixware partitions listed in a disklabel, under a 481 * dos-like partition. See parse_extended() for more information. 482 */ 483static void parse_unixware(struct parsed_partitions *state, 484 sector_t offset, sector_t size, int origin) 485{ 486#ifdef CONFIG_UNIXWARE_DISKLABEL 487 Sector sect; 488 struct unixware_disklabel *l; 489 struct unixware_slice *p; 490 491 l = read_part_sector(state, offset + 29, §); 492 if (!l) 493 return; 494 if (le32_to_cpu(l->d_magic) != UNIXWARE_DISKMAGIC || 495 le32_to_cpu(l->vtoc.v_magic) != UNIXWARE_DISKMAGIC2) { 496 put_dev_sector(sect); 497 return; 498 } 499 { 500 char tmp[1 + BDEVNAME_SIZE + 10 + 12 + 1]; 501 502 snprintf(tmp, sizeof(tmp), " %s%d: <unixware:", state->name, origin); 503 strlcat(state->pp_buf, tmp, PAGE_SIZE); 504 } 505 p = &l->vtoc.v_slice[1]; 506 /* I omit the 0th slice as it is the same as whole disk. */ 507 while (p - &l->vtoc.v_slice[0] < UNIXWARE_NUMSLICE) { 508 if (state->next == state->limit) 509 break; 510 511 if (p->s_label != UNIXWARE_FS_UNUSED) 512 put_partition(state, state->next++, 513 le32_to_cpu(p->start_sect), 514 le32_to_cpu(p->nr_sects)); 515 p++; 516 } 517 put_dev_sector(sect); 518 strlcat(state->pp_buf, " >\n", PAGE_SIZE); 519#endif 520} 521 522#define MINIX_NR_SUBPARTITIONS 4 523 524/* 525 * Minix 2.0.0/2.0.2 subpartition support. 526 * Anand Krishnamurthy <anandk@wiproge.med.ge.com> 527 * Rajeev V. Pillai <rajeevvp@yahoo.com> 528 */ 529static void parse_minix(struct parsed_partitions *state, 530 sector_t offset, sector_t size, int origin) 531{ 532#ifdef CONFIG_MINIX_SUBPARTITION 533 Sector sect; 534 unsigned char *data; 535 struct msdos_partition *p; 536 int i; 537 538 data = read_part_sector(state, offset, §); 539 if (!data) 540 return; 541 542 p = (struct msdos_partition *)(data + 0x1be); 543 544 /* The first sector of a Minix partition can have either 545 * a secondary MBR describing its subpartitions, or 546 * the normal boot sector. */ 547 if (msdos_magic_present(data + 510) && 548 p->sys_ind == MINIX_PARTITION) { /* subpartition table present */ 549 char tmp[1 + BDEVNAME_SIZE + 10 + 9 + 1]; 550 551 snprintf(tmp, sizeof(tmp), " %s%d: <minix:", state->name, origin); 552 strlcat(state->pp_buf, tmp, PAGE_SIZE); 553 for (i = 0; i < MINIX_NR_SUBPARTITIONS; i++, p++) { 554 if (state->next == state->limit) 555 break; 556 /* add each partition in use */ 557 if (p->sys_ind == MINIX_PARTITION) 558 put_partition(state, state->next++, 559 start_sect(p), nr_sects(p)); 560 } 561 strlcat(state->pp_buf, " >\n", PAGE_SIZE); 562 } 563 put_dev_sector(sect); 564#endif /* CONFIG_MINIX_SUBPARTITION */ 565} 566 567static struct { 568 unsigned char id; 569 void (*parse)(struct parsed_partitions *, sector_t, sector_t, int); 570} subtypes[] = { 571 {FREEBSD_PARTITION, parse_freebsd}, 572 {NETBSD_PARTITION, parse_netbsd}, 573 {OPENBSD_PARTITION, parse_openbsd}, 574 {MINIX_PARTITION, parse_minix}, 575 {UNIXWARE_PARTITION, parse_unixware}, 576 {SOLARIS_X86_PARTITION, parse_solaris_x86}, 577 {NEW_SOLARIS_X86_PARTITION, parse_solaris_x86}, 578 {0, NULL}, 579}; 580 581int msdos_partition(struct parsed_partitions *state) 582{ 583 sector_t sector_size; 584 Sector sect; 585 unsigned char *data; 586 struct msdos_partition *p; 587 struct fat_boot_sector *fb; 588 int slot; 589 u32 disksig; 590 591 sector_size = queue_logical_block_size(state->disk->queue) / 512; 592 data = read_part_sector(state, 0, §); 593 if (!data) 594 return -1; 595 596 /* 597 * Note order! (some AIX disks, e.g. unbootable kind, 598 * have no MSDOS 55aa) 599 */ 600 if (aix_magic_present(state, data)) { 601 put_dev_sector(sect); 602#ifdef CONFIG_AIX_PARTITION 603 return aix_partition(state); 604#else 605 strlcat(state->pp_buf, " [AIX]", PAGE_SIZE); 606 return 0; 607#endif 608 } 609 610 if (!msdos_magic_present(data + 510)) { 611 put_dev_sector(sect); 612 return 0; 613 } 614 615 /* 616 * Now that the 55aa signature is present, this is probably 617 * either the boot sector of a FAT filesystem or a DOS-type 618 * partition table. Reject this in case the boot indicator 619 * is not 0 or 0x80. 620 */ 621 p = (struct msdos_partition *) (data + 0x1be); 622 for (slot = 1; slot <= 4; slot++, p++) { 623 if (p->boot_ind != 0 && p->boot_ind != 0x80) { 624 /* 625 * Even without a valid boot indicator value 626 * its still possible this is valid FAT filesystem 627 * without a partition table. 628 */ 629 fb = (struct fat_boot_sector *) data; 630 if (slot == 1 && fb->reserved && fb->fats 631 && fat_valid_media(fb->media)) { 632 strlcat(state->pp_buf, "\n", PAGE_SIZE); 633 put_dev_sector(sect); 634 return 1; 635 } else { 636 put_dev_sector(sect); 637 return 0; 638 } 639 } 640 } 641 642#ifdef CONFIG_EFI_PARTITION 643 p = (struct msdos_partition *) (data + 0x1be); 644 for (slot = 1 ; slot <= 4 ; slot++, p++) { 645 /* If this is an EFI GPT disk, msdos should ignore it. */ 646 if (p->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT) { 647 put_dev_sector(sect); 648 return 0; 649 } 650 } 651#endif 652 p = (struct msdos_partition *) (data + 0x1be); 653 654 disksig = le32_to_cpup((__le32 *)(data + 0x1b8)); 655 656 /* 657 * Look for partitions in two passes: 658 * First find the primary and DOS-type extended partitions. 659 * On the second pass look inside *BSD, Unixware and Solaris partitions. 660 */ 661 662 state->next = 5; 663 for (slot = 1 ; slot <= 4 ; slot++, p++) { 664 sector_t start = start_sect(p)*sector_size; 665 sector_t size = nr_sects(p)*sector_size; 666 667 if (!size) 668 continue; 669 if (is_extended_partition(p)) { 670 /* 671 * prevent someone doing mkfs or mkswap on an 672 * extended partition, but leave room for LILO 673 * FIXME: this uses one logical sector for > 512b 674 * sector, although it may not be enough/proper. 675 */ 676 sector_t n = 2; 677 678 n = min(size, max(sector_size, n)); 679 put_partition(state, slot, start, n); 680 681 strlcat(state->pp_buf, " <", PAGE_SIZE); 682 parse_extended(state, start, size, disksig); 683 strlcat(state->pp_buf, " >", PAGE_SIZE); 684 continue; 685 } 686 put_partition(state, slot, start, size); 687 set_info(state, slot, disksig); 688 if (p->sys_ind == LINUX_RAID_PARTITION) 689 state->parts[slot].flags = ADDPART_FLAG_RAID; 690 if (p->sys_ind == DM6_PARTITION) 691 strlcat(state->pp_buf, "[DM]", PAGE_SIZE); 692 if (p->sys_ind == EZD_PARTITION) 693 strlcat(state->pp_buf, "[EZD]", PAGE_SIZE); 694 } 695 696 strlcat(state->pp_buf, "\n", PAGE_SIZE); 697 698 /* second pass - output for each on a separate line */ 699 p = (struct msdos_partition *) (0x1be + data); 700 for (slot = 1 ; slot <= 4 ; slot++, p++) { 701 unsigned char id = p->sys_ind; 702 int n; 703 704 if (!nr_sects(p)) 705 continue; 706 707 for (n = 0; subtypes[n].parse && id != subtypes[n].id; n++) 708 ; 709 710 if (!subtypes[n].parse) 711 continue; 712 subtypes[n].parse(state, start_sect(p) * sector_size, 713 nr_sects(p) * sector_size, slot); 714 } 715 put_dev_sector(sect); 716 return 1; 717} 718