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