linux/block/partitions/ldm.c
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   1/**
   2 * ldm - Support for Windows Logical Disk Manager (Dynamic Disks)
   3 *
   4 * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
   5 * Copyright (c) 2001-2012 Anton Altaparmakov
   6 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
   7 *
   8 * Documentation is available at http://www.linux-ntfs.org/doku.php?id=downloads 
   9 *
  10 * This program is free software; you can redistribute it and/or modify it under
  11 * the terms of the GNU General Public License as published by the Free Software
  12 * Foundation; either version 2 of the License, or (at your option) any later
  13 * version.
  14 *
  15 * This program is distributed in the hope that it will be useful, but WITHOUT
  16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  17 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  18 * details.
  19 *
  20 * You should have received a copy of the GNU General Public License along with
  21 * this program (in the main directory of the source in the file COPYING); if
  22 * not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  23 * Boston, MA  02111-1307  USA
  24 */
  25
  26#include <linux/slab.h>
  27#include <linux/pagemap.h>
  28#include <linux/stringify.h>
  29#include <linux/kernel.h>
  30#include "ldm.h"
  31#include "check.h"
  32#include "msdos.h"
  33
  34/**
  35 * ldm_debug/info/error/crit - Output an error message
  36 * @f:    A printf format string containing the message
  37 * @...:  Variables to substitute into @f
  38 *
  39 * ldm_debug() writes a DEBUG level message to the syslog but only if the
  40 * driver was compiled with debug enabled. Otherwise, the call turns into a NOP.
  41 */
  42#ifndef CONFIG_LDM_DEBUG
  43#define ldm_debug(...)  do {} while (0)
  44#else
  45#define ldm_debug(f, a...) _ldm_printk (KERN_DEBUG, __func__, f, ##a)
  46#endif
  47
  48#define ldm_crit(f, a...)  _ldm_printk (KERN_CRIT,  __func__, f, ##a)
  49#define ldm_error(f, a...) _ldm_printk (KERN_ERR,   __func__, f, ##a)
  50#define ldm_info(f, a...)  _ldm_printk (KERN_INFO,  __func__, f, ##a)
  51
  52static __printf(3, 4)
  53void _ldm_printk(const char *level, const char *function, const char *fmt, ...)
  54{
  55        struct va_format vaf;
  56        va_list args;
  57
  58        va_start (args, fmt);
  59
  60        vaf.fmt = fmt;
  61        vaf.va = &args;
  62
  63        printk("%s%s(): %pV\n", level, function, &vaf);
  64
  65        va_end(args);
  66}
  67
  68/**
  69 * ldm_parse_hexbyte - Convert a ASCII hex number to a byte
  70 * @src:  Pointer to at least 2 characters to convert.
  71 *
  72 * Convert a two character ASCII hex string to a number.
  73 *
  74 * Return:  0-255  Success, the byte was parsed correctly
  75 *          -1     Error, an invalid character was supplied
  76 */
  77static int ldm_parse_hexbyte (const u8 *src)
  78{
  79        unsigned int x;         /* For correct wrapping */
  80        int h;
  81
  82        /* high part */
  83        x = h = hex_to_bin(src[0]);
  84        if (h < 0)
  85                return -1;
  86
  87        /* low part */
  88        h = hex_to_bin(src[1]);
  89        if (h < 0)
  90                return -1;
  91
  92        return (x << 4) + h;
  93}
  94
  95/**
  96 * ldm_parse_guid - Convert GUID from ASCII to binary
  97 * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
  98 * @dest:  Memory block to hold binary GUID (16 bytes)
  99 *
 100 * N.B. The GUID need not be NULL terminated.
 101 *
 102 * Return:  'true'   @dest contains binary GUID
 103 *          'false'  @dest contents are undefined
 104 */
 105static bool ldm_parse_guid (const u8 *src, u8 *dest)
 106{
 107        static const int size[] = { 4, 2, 2, 2, 6 };
 108        int i, j, v;
 109
 110        if (src[8]  != '-' || src[13] != '-' ||
 111            src[18] != '-' || src[23] != '-')
 112                return false;
 113
 114        for (j = 0; j < 5; j++, src++)
 115                for (i = 0; i < size[j]; i++, src+=2, *dest++ = v)
 116                        if ((v = ldm_parse_hexbyte (src)) < 0)
 117                                return false;
 118
 119        return true;
 120}
 121
 122/**
 123 * ldm_parse_privhead - Read the LDM Database PRIVHEAD structure
 124 * @data:  Raw database PRIVHEAD structure loaded from the device
 125 * @ph:    In-memory privhead structure in which to return parsed information
 126 *
 127 * This parses the LDM database PRIVHEAD structure supplied in @data and
 128 * sets up the in-memory privhead structure @ph with the obtained information.
 129 *
 130 * Return:  'true'   @ph contains the PRIVHEAD data
 131 *          'false'  @ph contents are undefined
 132 */
 133static bool ldm_parse_privhead(const u8 *data, struct privhead *ph)
 134{
 135        bool is_vista = false;
 136
 137        BUG_ON(!data || !ph);
 138        if (MAGIC_PRIVHEAD != get_unaligned_be64(data)) {
 139                ldm_error("Cannot find PRIVHEAD structure. LDM database is"
 140                        " corrupt. Aborting.");
 141                return false;
 142        }
 143        ph->ver_major = get_unaligned_be16(data + 0x000C);
 144        ph->ver_minor = get_unaligned_be16(data + 0x000E);
 145        ph->logical_disk_start = get_unaligned_be64(data + 0x011B);
 146        ph->logical_disk_size = get_unaligned_be64(data + 0x0123);
 147        ph->config_start = get_unaligned_be64(data + 0x012B);
 148        ph->config_size = get_unaligned_be64(data + 0x0133);
 149        /* Version 2.11 is Win2k/XP and version 2.12 is Vista. */
 150        if (ph->ver_major == 2 && ph->ver_minor == 12)
 151                is_vista = true;
 152        if (!is_vista && (ph->ver_major != 2 || ph->ver_minor != 11)) {
 153                ldm_error("Expected PRIVHEAD version 2.11 or 2.12, got %d.%d."
 154                        " Aborting.", ph->ver_major, ph->ver_minor);
 155                return false;
 156        }
 157        ldm_debug("PRIVHEAD version %d.%d (Windows %s).", ph->ver_major,
 158                        ph->ver_minor, is_vista ? "Vista" : "2000/XP");
 159        if (ph->config_size != LDM_DB_SIZE) {   /* 1 MiB in sectors. */
 160                /* Warn the user and continue, carefully. */
 161                ldm_info("Database is normally %u bytes, it claims to "
 162                        "be %llu bytes.", LDM_DB_SIZE,
 163                        (unsigned long long)ph->config_size);
 164        }
 165        if ((ph->logical_disk_size == 0) || (ph->logical_disk_start +
 166                        ph->logical_disk_size > ph->config_start)) {
 167                ldm_error("PRIVHEAD disk size doesn't match real disk size");
 168                return false;
 169        }
 170        if (!ldm_parse_guid(data + 0x0030, ph->disk_id)) {
 171                ldm_error("PRIVHEAD contains an invalid GUID.");
 172                return false;
 173        }
 174        ldm_debug("Parsed PRIVHEAD successfully.");
 175        return true;
 176}
 177
 178/**
 179 * ldm_parse_tocblock - Read the LDM Database TOCBLOCK structure
 180 * @data:  Raw database TOCBLOCK structure loaded from the device
 181 * @toc:   In-memory toc structure in which to return parsed information
 182 *
 183 * This parses the LDM Database TOCBLOCK (table of contents) structure supplied
 184 * in @data and sets up the in-memory tocblock structure @toc with the obtained
 185 * information.
 186 *
 187 * N.B.  The *_start and *_size values returned in @toc are not range-checked.
 188 *
 189 * Return:  'true'   @toc contains the TOCBLOCK data
 190 *          'false'  @toc contents are undefined
 191 */
 192static bool ldm_parse_tocblock (const u8 *data, struct tocblock *toc)
 193{
 194        BUG_ON (!data || !toc);
 195
 196        if (MAGIC_TOCBLOCK != get_unaligned_be64(data)) {
 197                ldm_crit ("Cannot find TOCBLOCK, database may be corrupt.");
 198                return false;
 199        }
 200        strncpy (toc->bitmap1_name, data + 0x24, sizeof (toc->bitmap1_name));
 201        toc->bitmap1_name[sizeof (toc->bitmap1_name) - 1] = 0;
 202        toc->bitmap1_start = get_unaligned_be64(data + 0x2E);
 203        toc->bitmap1_size  = get_unaligned_be64(data + 0x36);
 204
 205        if (strncmp (toc->bitmap1_name, TOC_BITMAP1,
 206                        sizeof (toc->bitmap1_name)) != 0) {
 207                ldm_crit ("TOCBLOCK's first bitmap is '%s', should be '%s'.",
 208                                TOC_BITMAP1, toc->bitmap1_name);
 209                return false;
 210        }
 211        strncpy (toc->bitmap2_name, data + 0x46, sizeof (toc->bitmap2_name));
 212        toc->bitmap2_name[sizeof (toc->bitmap2_name) - 1] = 0;
 213        toc->bitmap2_start = get_unaligned_be64(data + 0x50);
 214        toc->bitmap2_size  = get_unaligned_be64(data + 0x58);
 215        if (strncmp (toc->bitmap2_name, TOC_BITMAP2,
 216                        sizeof (toc->bitmap2_name)) != 0) {
 217                ldm_crit ("TOCBLOCK's second bitmap is '%s', should be '%s'.",
 218                                TOC_BITMAP2, toc->bitmap2_name);
 219                return false;
 220        }
 221        ldm_debug ("Parsed TOCBLOCK successfully.");
 222        return true;
 223}
 224
 225/**
 226 * ldm_parse_vmdb - Read the LDM Database VMDB structure
 227 * @data:  Raw database VMDB structure loaded from the device
 228 * @vm:    In-memory vmdb structure in which to return parsed information
 229 *
 230 * This parses the LDM Database VMDB structure supplied in @data and sets up
 231 * the in-memory vmdb structure @vm with the obtained information.
 232 *
 233 * N.B.  The *_start, *_size and *_seq values will be range-checked later.
 234 *
 235 * Return:  'true'   @vm contains VMDB info
 236 *          'false'  @vm contents are undefined
 237 */
 238static bool ldm_parse_vmdb (const u8 *data, struct vmdb *vm)
 239{
 240        BUG_ON (!data || !vm);
 241
 242        if (MAGIC_VMDB != get_unaligned_be32(data)) {
 243                ldm_crit ("Cannot find the VMDB, database may be corrupt.");
 244                return false;
 245        }
 246
 247        vm->ver_major = get_unaligned_be16(data + 0x12);
 248        vm->ver_minor = get_unaligned_be16(data + 0x14);
 249        if ((vm->ver_major != 4) || (vm->ver_minor != 10)) {
 250                ldm_error ("Expected VMDB version %d.%d, got %d.%d. "
 251                        "Aborting.", 4, 10, vm->ver_major, vm->ver_minor);
 252                return false;
 253        }
 254
 255        vm->vblk_size     = get_unaligned_be32(data + 0x08);
 256        if (vm->vblk_size == 0) {
 257                ldm_error ("Illegal VBLK size");
 258                return false;
 259        }
 260
 261        vm->vblk_offset   = get_unaligned_be32(data + 0x0C);
 262        vm->last_vblk_seq = get_unaligned_be32(data + 0x04);
 263
 264        ldm_debug ("Parsed VMDB successfully.");
 265        return true;
 266}
 267
 268/**
 269 * ldm_compare_privheads - Compare two privhead objects
 270 * @ph1:  First privhead
 271 * @ph2:  Second privhead
 272 *
 273 * This compares the two privhead structures @ph1 and @ph2.
 274 *
 275 * Return:  'true'   Identical
 276 *          'false'  Different
 277 */
 278static bool ldm_compare_privheads (const struct privhead *ph1,
 279                                   const struct privhead *ph2)
 280{
 281        BUG_ON (!ph1 || !ph2);
 282
 283        return ((ph1->ver_major          == ph2->ver_major)             &&
 284                (ph1->ver_minor          == ph2->ver_minor)             &&
 285                (ph1->logical_disk_start == ph2->logical_disk_start)    &&
 286                (ph1->logical_disk_size  == ph2->logical_disk_size)     &&
 287                (ph1->config_start       == ph2->config_start)          &&
 288                (ph1->config_size        == ph2->config_size)           &&
 289                !memcmp (ph1->disk_id, ph2->disk_id, GUID_SIZE));
 290}
 291
 292/**
 293 * ldm_compare_tocblocks - Compare two tocblock objects
 294 * @toc1:  First toc
 295 * @toc2:  Second toc
 296 *
 297 * This compares the two tocblock structures @toc1 and @toc2.
 298 *
 299 * Return:  'true'   Identical
 300 *          'false'  Different
 301 */
 302static bool ldm_compare_tocblocks (const struct tocblock *toc1,
 303                                   const struct tocblock *toc2)
 304{
 305        BUG_ON (!toc1 || !toc2);
 306
 307        return ((toc1->bitmap1_start == toc2->bitmap1_start)    &&
 308                (toc1->bitmap1_size  == toc2->bitmap1_size)     &&
 309                (toc1->bitmap2_start == toc2->bitmap2_start)    &&
 310                (toc1->bitmap2_size  == toc2->bitmap2_size)     &&
 311                !strncmp (toc1->bitmap1_name, toc2->bitmap1_name,
 312                        sizeof (toc1->bitmap1_name))            &&
 313                !strncmp (toc1->bitmap2_name, toc2->bitmap2_name,
 314                        sizeof (toc1->bitmap2_name)));
 315}
 316
 317/**
 318 * ldm_validate_privheads - Compare the primary privhead with its backups
 319 * @state: Partition check state including device holding the LDM Database
 320 * @ph1:   Memory struct to fill with ph contents
 321 *
 322 * Read and compare all three privheads from disk.
 323 *
 324 * The privheads on disk show the size and location of the main disk area and
 325 * the configuration area (the database).  The values are range-checked against
 326 * @hd, which contains the real size of the disk.
 327 *
 328 * Return:  'true'   Success
 329 *          'false'  Error
 330 */
 331static bool ldm_validate_privheads(struct parsed_partitions *state,
 332                                   struct privhead *ph1)
 333{
 334        static const int off[3] = { OFF_PRIV1, OFF_PRIV2, OFF_PRIV3 };
 335        struct privhead *ph[3] = { ph1 };
 336        Sector sect;
 337        u8 *data;
 338        bool result = false;
 339        long num_sects;
 340        int i;
 341
 342        BUG_ON (!state || !ph1);
 343
 344        ph[1] = kmalloc (sizeof (*ph[1]), GFP_KERNEL);
 345        ph[2] = kmalloc (sizeof (*ph[2]), GFP_KERNEL);
 346        if (!ph[1] || !ph[2]) {
 347                ldm_crit ("Out of memory.");
 348                goto out;
 349        }
 350
 351        /* off[1 & 2] are relative to ph[0]->config_start */
 352        ph[0]->config_start = 0;
 353
 354        /* Read and parse privheads */
 355        for (i = 0; i < 3; i++) {
 356                data = read_part_sector(state, ph[0]->config_start + off[i],
 357                                        &sect);
 358                if (!data) {
 359                        ldm_crit ("Disk read failed.");
 360                        goto out;
 361                }
 362                result = ldm_parse_privhead (data, ph[i]);
 363                put_dev_sector (sect);
 364                if (!result) {
 365                        ldm_error ("Cannot find PRIVHEAD %d.", i+1); /* Log again */
 366                        if (i < 2)
 367                                goto out;       /* Already logged */
 368                        else
 369                                break;  /* FIXME ignore for now, 3rd PH can fail on odd-sized disks */
 370                }
 371        }
 372
 373        num_sects = state->bdev->bd_inode->i_size >> 9;
 374
 375        if ((ph[0]->config_start > num_sects) ||
 376           ((ph[0]->config_start + ph[0]->config_size) > num_sects)) {
 377                ldm_crit ("Database extends beyond the end of the disk.");
 378                goto out;
 379        }
 380
 381        if ((ph[0]->logical_disk_start > ph[0]->config_start) ||
 382           ((ph[0]->logical_disk_start + ph[0]->logical_disk_size)
 383                    > ph[0]->config_start)) {
 384                ldm_crit ("Disk and database overlap.");
 385                goto out;
 386        }
 387
 388        if (!ldm_compare_privheads (ph[0], ph[1])) {
 389                ldm_crit ("Primary and backup PRIVHEADs don't match.");
 390                goto out;
 391        }
 392        /* FIXME ignore this for now
 393        if (!ldm_compare_privheads (ph[0], ph[2])) {
 394                ldm_crit ("Primary and backup PRIVHEADs don't match.");
 395                goto out;
 396        }*/
 397        ldm_debug ("Validated PRIVHEADs successfully.");
 398        result = true;
 399out:
 400        kfree (ph[1]);
 401        kfree (ph[2]);
 402        return result;
 403}
 404
 405/**
 406 * ldm_validate_tocblocks - Validate the table of contents and its backups
 407 * @state: Partition check state including device holding the LDM Database
 408 * @base:  Offset, into @state->bdev, of the database
 409 * @ldb:   Cache of the database structures
 410 *
 411 * Find and compare the four tables of contents of the LDM Database stored on
 412 * @state->bdev and return the parsed information into @toc1.
 413 *
 414 * The offsets and sizes of the configs are range-checked against a privhead.
 415 *
 416 * Return:  'true'   @toc1 contains validated TOCBLOCK info
 417 *          'false'  @toc1 contents are undefined
 418 */
 419static bool ldm_validate_tocblocks(struct parsed_partitions *state,
 420                                   unsigned long base, struct ldmdb *ldb)
 421{
 422        static const int off[4] = { OFF_TOCB1, OFF_TOCB2, OFF_TOCB3, OFF_TOCB4};
 423        struct tocblock *tb[4];
 424        struct privhead *ph;
 425        Sector sect;
 426        u8 *data;
 427        int i, nr_tbs;
 428        bool result = false;
 429
 430        BUG_ON(!state || !ldb);
 431        ph = &ldb->ph;
 432        tb[0] = &ldb->toc;
 433        tb[1] = kmalloc(sizeof(*tb[1]) * 3, GFP_KERNEL);
 434        if (!tb[1]) {
 435                ldm_crit("Out of memory.");
 436                goto err;
 437        }
 438        tb[2] = (struct tocblock*)((u8*)tb[1] + sizeof(*tb[1]));
 439        tb[3] = (struct tocblock*)((u8*)tb[2] + sizeof(*tb[2]));
 440        /*
 441         * Try to read and parse all four TOCBLOCKs.
 442         *
 443         * Windows Vista LDM v2.12 does not always have all four TOCBLOCKs so
 444         * skip any that fail as long as we get at least one valid TOCBLOCK.
 445         */
 446        for (nr_tbs = i = 0; i < 4; i++) {
 447                data = read_part_sector(state, base + off[i], &sect);
 448                if (!data) {
 449                        ldm_error("Disk read failed for TOCBLOCK %d.", i);
 450                        continue;
 451                }
 452                if (ldm_parse_tocblock(data, tb[nr_tbs]))
 453                        nr_tbs++;
 454                put_dev_sector(sect);
 455        }
 456        if (!nr_tbs) {
 457                ldm_crit("Failed to find a valid TOCBLOCK.");
 458                goto err;
 459        }
 460        /* Range check the TOCBLOCK against a privhead. */
 461        if (((tb[0]->bitmap1_start + tb[0]->bitmap1_size) > ph->config_size) ||
 462                        ((tb[0]->bitmap2_start + tb[0]->bitmap2_size) >
 463                        ph->config_size)) {
 464                ldm_crit("The bitmaps are out of range.  Giving up.");
 465                goto err;
 466        }
 467        /* Compare all loaded TOCBLOCKs. */
 468        for (i = 1; i < nr_tbs; i++) {
 469                if (!ldm_compare_tocblocks(tb[0], tb[i])) {
 470                        ldm_crit("TOCBLOCKs 0 and %d do not match.", i);
 471                        goto err;
 472                }
 473        }
 474        ldm_debug("Validated %d TOCBLOCKs successfully.", nr_tbs);
 475        result = true;
 476err:
 477        kfree(tb[1]);
 478        return result;
 479}
 480
 481/**
 482 * ldm_validate_vmdb - Read the VMDB and validate it
 483 * @state: Partition check state including device holding the LDM Database
 484 * @base:  Offset, into @bdev, of the database
 485 * @ldb:   Cache of the database structures
 486 *
 487 * Find the vmdb of the LDM Database stored on @bdev and return the parsed
 488 * information in @ldb.
 489 *
 490 * Return:  'true'   @ldb contains validated VBDB info
 491 *          'false'  @ldb contents are undefined
 492 */
 493static bool ldm_validate_vmdb(struct parsed_partitions *state,
 494                              unsigned long base, struct ldmdb *ldb)
 495{
 496        Sector sect;
 497        u8 *data;
 498        bool result = false;
 499        struct vmdb *vm;
 500        struct tocblock *toc;
 501
 502        BUG_ON (!state || !ldb);
 503
 504        vm  = &ldb->vm;
 505        toc = &ldb->toc;
 506
 507        data = read_part_sector(state, base + OFF_VMDB, &sect);
 508        if (!data) {
 509                ldm_crit ("Disk read failed.");
 510                return false;
 511        }
 512
 513        if (!ldm_parse_vmdb (data, vm))
 514                goto out;                               /* Already logged */
 515
 516        /* Are there uncommitted transactions? */
 517        if (get_unaligned_be16(data + 0x10) != 0x01) {
 518                ldm_crit ("Database is not in a consistent state.  Aborting.");
 519                goto out;
 520        }
 521
 522        if (vm->vblk_offset != 512)
 523                ldm_info ("VBLKs start at offset 0x%04x.", vm->vblk_offset);
 524
 525        /*
 526         * The last_vblkd_seq can be before the end of the vmdb, just make sure
 527         * it is not out of bounds.
 528         */
 529        if ((vm->vblk_size * vm->last_vblk_seq) > (toc->bitmap1_size << 9)) {
 530                ldm_crit ("VMDB exceeds allowed size specified by TOCBLOCK.  "
 531                                "Database is corrupt.  Aborting.");
 532                goto out;
 533        }
 534
 535        result = true;
 536out:
 537        put_dev_sector (sect);
 538        return result;
 539}
 540
 541
 542/**
 543 * ldm_validate_partition_table - Determine whether bdev might be a dynamic disk
 544 * @state: Partition check state including device holding the LDM Database
 545 *
 546 * This function provides a weak test to decide whether the device is a dynamic
 547 * disk or not.  It looks for an MS-DOS-style partition table containing at
 548 * least one partition of type 0x42 (formerly SFS, now used by Windows for
 549 * dynamic disks).
 550 *
 551 * N.B.  The only possible error can come from the read_part_sector and that is
 552 *       only likely to happen if the underlying device is strange.  If that IS
 553 *       the case we should return zero to let someone else try.
 554 *
 555 * Return:  'true'   @state->bdev is a dynamic disk
 556 *          'false'  @state->bdev is not a dynamic disk, or an error occurred
 557 */
 558static bool ldm_validate_partition_table(struct parsed_partitions *state)
 559{
 560        Sector sect;
 561        u8 *data;
 562        struct partition *p;
 563        int i;
 564        bool result = false;
 565
 566        BUG_ON(!state);
 567
 568        data = read_part_sector(state, 0, &sect);
 569        if (!data) {
 570                ldm_info ("Disk read failed.");
 571                return false;
 572        }
 573
 574        if (*(__le16*) (data + 0x01FE) != cpu_to_le16 (MSDOS_LABEL_MAGIC))
 575                goto out;
 576
 577        p = (struct partition*)(data + 0x01BE);
 578        for (i = 0; i < 4; i++, p++)
 579                if (SYS_IND (p) == LDM_PARTITION) {
 580                        result = true;
 581                        break;
 582                }
 583
 584        if (result)
 585                ldm_debug ("Found W2K dynamic disk partition type.");
 586
 587out:
 588        put_dev_sector (sect);
 589        return result;
 590}
 591
 592/**
 593 * ldm_get_disk_objid - Search a linked list of vblk's for a given Disk Id
 594 * @ldb:  Cache of the database structures
 595 *
 596 * The LDM Database contains a list of all partitions on all dynamic disks.
 597 * The primary PRIVHEAD, at the beginning of the physical disk, tells us
 598 * the GUID of this disk.  This function searches for the GUID in a linked
 599 * list of vblk's.
 600 *
 601 * Return:  Pointer, A matching vblk was found
 602 *          NULL,    No match, or an error
 603 */
 604static struct vblk * ldm_get_disk_objid (const struct ldmdb *ldb)
 605{
 606        struct list_head *item;
 607
 608        BUG_ON (!ldb);
 609
 610        list_for_each (item, &ldb->v_disk) {
 611                struct vblk *v = list_entry (item, struct vblk, list);
 612                if (!memcmp (v->vblk.disk.disk_id, ldb->ph.disk_id, GUID_SIZE))
 613                        return v;
 614        }
 615
 616        return NULL;
 617}
 618
 619/**
 620 * ldm_create_data_partitions - Create data partitions for this device
 621 * @pp:   List of the partitions parsed so far
 622 * @ldb:  Cache of the database structures
 623 *
 624 * The database contains ALL the partitions for ALL disk groups, so we need to
 625 * filter out this specific disk. Using the disk's object id, we can find all
 626 * the partitions in the database that belong to this disk.
 627 *
 628 * Add each partition in our database, to the parsed_partitions structure.
 629 *
 630 * N.B.  This function creates the partitions in the order it finds partition
 631 *       objects in the linked list.
 632 *
 633 * Return:  'true'   Partition created
 634 *          'false'  Error, probably a range checking problem
 635 */
 636static bool ldm_create_data_partitions (struct parsed_partitions *pp,
 637                                        const struct ldmdb *ldb)
 638{
 639        struct list_head *item;
 640        struct vblk *vb;
 641        struct vblk *disk;
 642        struct vblk_part *part;
 643        int part_num = 1;
 644
 645        BUG_ON (!pp || !ldb);
 646
 647        disk = ldm_get_disk_objid (ldb);
 648        if (!disk) {
 649                ldm_crit ("Can't find the ID of this disk in the database.");
 650                return false;
 651        }
 652
 653        strlcat(pp->pp_buf, " [LDM]", PAGE_SIZE);
 654
 655        /* Create the data partitions */
 656        list_for_each (item, &ldb->v_part) {
 657                vb = list_entry (item, struct vblk, list);
 658                part = &vb->vblk.part;
 659
 660                if (part->disk_id != disk->obj_id)
 661                        continue;
 662
 663                put_partition (pp, part_num, ldb->ph.logical_disk_start +
 664                                part->start, part->size);
 665                part_num++;
 666        }
 667
 668        strlcat(pp->pp_buf, "\n", PAGE_SIZE);
 669        return true;
 670}
 671
 672
 673/**
 674 * ldm_relative - Calculate the next relative offset
 675 * @buffer:  Block of data being worked on
 676 * @buflen:  Size of the block of data
 677 * @base:    Size of the previous fixed width fields
 678 * @offset:  Cumulative size of the previous variable-width fields
 679 *
 680 * Because many of the VBLK fields are variable-width, it's necessary
 681 * to calculate each offset based on the previous one and the length
 682 * of the field it pointed to.
 683 *
 684 * Return:  -1 Error, the calculated offset exceeded the size of the buffer
 685 *           n OK, a range-checked offset into buffer
 686 */
 687static int ldm_relative(const u8 *buffer, int buflen, int base, int offset)
 688{
 689
 690        base += offset;
 691        if (!buffer || offset < 0 || base > buflen) {
 692                if (!buffer)
 693                        ldm_error("!buffer");
 694                if (offset < 0)
 695                        ldm_error("offset (%d) < 0", offset);
 696                if (base > buflen)
 697                        ldm_error("base (%d) > buflen (%d)", base, buflen);
 698                return -1;
 699        }
 700        if (base + buffer[base] >= buflen) {
 701                ldm_error("base (%d) + buffer[base] (%d) >= buflen (%d)", base,
 702                                buffer[base], buflen);
 703                return -1;
 704        }
 705        return buffer[base] + offset + 1;
 706}
 707
 708/**
 709 * ldm_get_vnum - Convert a variable-width, big endian number, into cpu order
 710 * @block:  Pointer to the variable-width number to convert
 711 *
 712 * Large numbers in the LDM Database are often stored in a packed format.  Each
 713 * number is prefixed by a one byte width marker.  All numbers in the database
 714 * are stored in big-endian byte order.  This function reads one of these
 715 * numbers and returns the result
 716 *
 717 * N.B.  This function DOES NOT perform any range checking, though the most
 718 *       it will read is eight bytes.
 719 *
 720 * Return:  n A number
 721 *          0 Zero, or an error occurred
 722 */
 723static u64 ldm_get_vnum (const u8 *block)
 724{
 725        u64 tmp = 0;
 726        u8 length;
 727
 728        BUG_ON (!block);
 729
 730        length = *block++;
 731
 732        if (length && length <= 8)
 733                while (length--)
 734                        tmp = (tmp << 8) | *block++;
 735        else
 736                ldm_error ("Illegal length %d.", length);
 737
 738        return tmp;
 739}
 740
 741/**
 742 * ldm_get_vstr - Read a length-prefixed string into a buffer
 743 * @block:   Pointer to the length marker
 744 * @buffer:  Location to copy string to
 745 * @buflen:  Size of the output buffer
 746 *
 747 * Many of the strings in the LDM Database are not NULL terminated.  Instead
 748 * they are prefixed by a one byte length marker.  This function copies one of
 749 * these strings into a buffer.
 750 *
 751 * N.B.  This function DOES NOT perform any range checking on the input.
 752 *       If the buffer is too small, the output will be truncated.
 753 *
 754 * Return:  0, Error and @buffer contents are undefined
 755 *          n, String length in characters (excluding NULL)
 756 *          buflen-1, String was truncated.
 757 */
 758static int ldm_get_vstr (const u8 *block, u8 *buffer, int buflen)
 759{
 760        int length;
 761
 762        BUG_ON (!block || !buffer);
 763
 764        length = block[0];
 765        if (length >= buflen) {
 766                ldm_error ("Truncating string %d -> %d.", length, buflen);
 767                length = buflen - 1;
 768        }
 769        memcpy (buffer, block + 1, length);
 770        buffer[length] = 0;
 771        return length;
 772}
 773
 774
 775/**
 776 * ldm_parse_cmp3 - Read a raw VBLK Component object into a vblk structure
 777 * @buffer:  Block of data being worked on
 778 * @buflen:  Size of the block of data
 779 * @vb:      In-memory vblk in which to return information
 780 *
 781 * Read a raw VBLK Component object (version 3) into a vblk structure.
 782 *
 783 * Return:  'true'   @vb contains a Component VBLK
 784 *          'false'  @vb contents are not defined
 785 */
 786static bool ldm_parse_cmp3 (const u8 *buffer, int buflen, struct vblk *vb)
 787{
 788        int r_objid, r_name, r_vstate, r_child, r_parent, r_stripe, r_cols, len;
 789        struct vblk_comp *comp;
 790
 791        BUG_ON (!buffer || !vb);
 792
 793        r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
 794        r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
 795        r_vstate = ldm_relative (buffer, buflen, 0x18, r_name);
 796        r_child  = ldm_relative (buffer, buflen, 0x1D, r_vstate);
 797        r_parent = ldm_relative (buffer, buflen, 0x2D, r_child);
 798
 799        if (buffer[0x12] & VBLK_FLAG_COMP_STRIPE) {
 800                r_stripe = ldm_relative (buffer, buflen, 0x2E, r_parent);
 801                r_cols   = ldm_relative (buffer, buflen, 0x2E, r_stripe);
 802                len = r_cols;
 803        } else {
 804                r_stripe = 0;
 805                r_cols   = 0;
 806                len = r_parent;
 807        }
 808        if (len < 0)
 809                return false;
 810
 811        len += VBLK_SIZE_CMP3;
 812        if (len != get_unaligned_be32(buffer + 0x14))
 813                return false;
 814
 815        comp = &vb->vblk.comp;
 816        ldm_get_vstr (buffer + 0x18 + r_name, comp->state,
 817                sizeof (comp->state));
 818        comp->type      = buffer[0x18 + r_vstate];
 819        comp->children  = ldm_get_vnum (buffer + 0x1D + r_vstate);
 820        comp->parent_id = ldm_get_vnum (buffer + 0x2D + r_child);
 821        comp->chunksize = r_stripe ? ldm_get_vnum (buffer+r_parent+0x2E) : 0;
 822
 823        return true;
 824}
 825
 826/**
 827 * ldm_parse_dgr3 - Read a raw VBLK Disk Group object into a vblk structure
 828 * @buffer:  Block of data being worked on
 829 * @buflen:  Size of the block of data
 830 * @vb:      In-memory vblk in which to return information
 831 *
 832 * Read a raw VBLK Disk Group object (version 3) into a vblk structure.
 833 *
 834 * Return:  'true'   @vb contains a Disk Group VBLK
 835 *          'false'  @vb contents are not defined
 836 */
 837static int ldm_parse_dgr3 (const u8 *buffer, int buflen, struct vblk *vb)
 838{
 839        int r_objid, r_name, r_diskid, r_id1, r_id2, len;
 840        struct vblk_dgrp *dgrp;
 841
 842        BUG_ON (!buffer || !vb);
 843
 844        r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
 845        r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
 846        r_diskid = ldm_relative (buffer, buflen, 0x18, r_name);
 847
 848        if (buffer[0x12] & VBLK_FLAG_DGR3_IDS) {
 849                r_id1 = ldm_relative (buffer, buflen, 0x24, r_diskid);
 850                r_id2 = ldm_relative (buffer, buflen, 0x24, r_id1);
 851                len = r_id2;
 852        } else {
 853                r_id1 = 0;
 854                r_id2 = 0;
 855                len = r_diskid;
 856        }
 857        if (len < 0)
 858                return false;
 859
 860        len += VBLK_SIZE_DGR3;
 861        if (len != get_unaligned_be32(buffer + 0x14))
 862                return false;
 863
 864        dgrp = &vb->vblk.dgrp;
 865        ldm_get_vstr (buffer + 0x18 + r_name, dgrp->disk_id,
 866                sizeof (dgrp->disk_id));
 867        return true;
 868}
 869
 870/**
 871 * ldm_parse_dgr4 - Read a raw VBLK Disk Group object into a vblk structure
 872 * @buffer:  Block of data being worked on
 873 * @buflen:  Size of the block of data
 874 * @vb:      In-memory vblk in which to return information
 875 *
 876 * Read a raw VBLK Disk Group object (version 4) into a vblk structure.
 877 *
 878 * Return:  'true'   @vb contains a Disk Group VBLK
 879 *          'false'  @vb contents are not defined
 880 */
 881static bool ldm_parse_dgr4 (const u8 *buffer, int buflen, struct vblk *vb)
 882{
 883        char buf[64];
 884        int r_objid, r_name, r_id1, r_id2, len;
 885        struct vblk_dgrp *dgrp;
 886
 887        BUG_ON (!buffer || !vb);
 888
 889        r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
 890        r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
 891
 892        if (buffer[0x12] & VBLK_FLAG_DGR4_IDS) {
 893                r_id1 = ldm_relative (buffer, buflen, 0x44, r_name);
 894                r_id2 = ldm_relative (buffer, buflen, 0x44, r_id1);
 895                len = r_id2;
 896        } else {
 897                r_id1 = 0;
 898                r_id2 = 0;
 899                len = r_name;
 900        }
 901        if (len < 0)
 902                return false;
 903
 904        len += VBLK_SIZE_DGR4;
 905        if (len != get_unaligned_be32(buffer + 0x14))
 906                return false;
 907
 908        dgrp = &vb->vblk.dgrp;
 909
 910        ldm_get_vstr (buffer + 0x18 + r_objid, buf, sizeof (buf));
 911        return true;
 912}
 913
 914/**
 915 * ldm_parse_dsk3 - Read a raw VBLK Disk object into a vblk structure
 916 * @buffer:  Block of data being worked on
 917 * @buflen:  Size of the block of data
 918 * @vb:      In-memory vblk in which to return information
 919 *
 920 * Read a raw VBLK Disk object (version 3) into a vblk structure.
 921 *
 922 * Return:  'true'   @vb contains a Disk VBLK
 923 *          'false'  @vb contents are not defined
 924 */
 925static bool ldm_parse_dsk3 (const u8 *buffer, int buflen, struct vblk *vb)
 926{
 927        int r_objid, r_name, r_diskid, r_altname, len;
 928        struct vblk_disk *disk;
 929
 930        BUG_ON (!buffer || !vb);
 931
 932        r_objid   = ldm_relative (buffer, buflen, 0x18, 0);
 933        r_name    = ldm_relative (buffer, buflen, 0x18, r_objid);
 934        r_diskid  = ldm_relative (buffer, buflen, 0x18, r_name);
 935        r_altname = ldm_relative (buffer, buflen, 0x18, r_diskid);
 936        len = r_altname;
 937        if (len < 0)
 938                return false;
 939
 940        len += VBLK_SIZE_DSK3;
 941        if (len != get_unaligned_be32(buffer + 0x14))
 942                return false;
 943
 944        disk = &vb->vblk.disk;
 945        ldm_get_vstr (buffer + 0x18 + r_diskid, disk->alt_name,
 946                sizeof (disk->alt_name));
 947        if (!ldm_parse_guid (buffer + 0x19 + r_name, disk->disk_id))
 948                return false;
 949
 950        return true;
 951}
 952
 953/**
 954 * ldm_parse_dsk4 - Read a raw VBLK Disk object into a vblk structure
 955 * @buffer:  Block of data being worked on
 956 * @buflen:  Size of the block of data
 957 * @vb:      In-memory vblk in which to return information
 958 *
 959 * Read a raw VBLK Disk object (version 4) into a vblk structure.
 960 *
 961 * Return:  'true'   @vb contains a Disk VBLK
 962 *          'false'  @vb contents are not defined
 963 */
 964static bool ldm_parse_dsk4 (const u8 *buffer, int buflen, struct vblk *vb)
 965{
 966        int r_objid, r_name, len;
 967        struct vblk_disk *disk;
 968
 969        BUG_ON (!buffer || !vb);
 970
 971        r_objid = ldm_relative (buffer, buflen, 0x18, 0);
 972        r_name  = ldm_relative (buffer, buflen, 0x18, r_objid);
 973        len     = r_name;
 974        if (len < 0)
 975                return false;
 976
 977        len += VBLK_SIZE_DSK4;
 978        if (len != get_unaligned_be32(buffer + 0x14))
 979                return false;
 980
 981        disk = &vb->vblk.disk;
 982        memcpy (disk->disk_id, buffer + 0x18 + r_name, GUID_SIZE);
 983        return true;
 984}
 985
 986/**
 987 * ldm_parse_prt3 - Read a raw VBLK Partition object into a vblk structure
 988 * @buffer:  Block of data being worked on
 989 * @buflen:  Size of the block of data
 990 * @vb:      In-memory vblk in which to return information
 991 *
 992 * Read a raw VBLK Partition object (version 3) into a vblk structure.
 993 *
 994 * Return:  'true'   @vb contains a Partition VBLK
 995 *          'false'  @vb contents are not defined
 996 */
 997static bool ldm_parse_prt3(const u8 *buffer, int buflen, struct vblk *vb)
 998{
 999        int r_objid, r_name, r_size, r_parent, r_diskid, r_index, len;
1000        struct vblk_part *part;
1001
1002        BUG_ON(!buffer || !vb);
1003        r_objid = ldm_relative(buffer, buflen, 0x18, 0);
1004        if (r_objid < 0) {
1005                ldm_error("r_objid %d < 0", r_objid);
1006                return false;
1007        }
1008        r_name = ldm_relative(buffer, buflen, 0x18, r_objid);
1009        if (r_name < 0) {
1010                ldm_error("r_name %d < 0", r_name);
1011                return false;
1012        }
1013        r_size = ldm_relative(buffer, buflen, 0x34, r_name);
1014        if (r_size < 0) {
1015                ldm_error("r_size %d < 0", r_size);
1016                return false;
1017        }
1018        r_parent = ldm_relative(buffer, buflen, 0x34, r_size);
1019        if (r_parent < 0) {
1020                ldm_error("r_parent %d < 0", r_parent);
1021                return false;
1022        }
1023        r_diskid = ldm_relative(buffer, buflen, 0x34, r_parent);
1024        if (r_diskid < 0) {
1025                ldm_error("r_diskid %d < 0", r_diskid);
1026                return false;
1027        }
1028        if (buffer[0x12] & VBLK_FLAG_PART_INDEX) {
1029                r_index = ldm_relative(buffer, buflen, 0x34, r_diskid);
1030                if (r_index < 0) {
1031                        ldm_error("r_index %d < 0", r_index);
1032                        return false;
1033                }
1034                len = r_index;
1035        } else {
1036                r_index = 0;
1037                len = r_diskid;
1038        }
1039        if (len < 0) {
1040                ldm_error("len %d < 0", len);
1041                return false;
1042        }
1043        len += VBLK_SIZE_PRT3;
1044        if (len > get_unaligned_be32(buffer + 0x14)) {
1045                ldm_error("len %d > BE32(buffer + 0x14) %d", len,
1046                                get_unaligned_be32(buffer + 0x14));
1047                return false;
1048        }
1049        part = &vb->vblk.part;
1050        part->start = get_unaligned_be64(buffer + 0x24 + r_name);
1051        part->volume_offset = get_unaligned_be64(buffer + 0x2C + r_name);
1052        part->size = ldm_get_vnum(buffer + 0x34 + r_name);
1053        part->parent_id = ldm_get_vnum(buffer + 0x34 + r_size);
1054        part->disk_id = ldm_get_vnum(buffer + 0x34 + r_parent);
1055        if (vb->flags & VBLK_FLAG_PART_INDEX)
1056                part->partnum = buffer[0x35 + r_diskid];
1057        else
1058                part->partnum = 0;
1059        return true;
1060}
1061
1062/**
1063 * ldm_parse_vol5 - Read a raw VBLK Volume object into a vblk structure
1064 * @buffer:  Block of data being worked on
1065 * @buflen:  Size of the block of data
1066 * @vb:      In-memory vblk in which to return information
1067 *
1068 * Read a raw VBLK Volume object (version 5) into a vblk structure.
1069 *
1070 * Return:  'true'   @vb contains a Volume VBLK
1071 *          'false'  @vb contents are not defined
1072 */
1073static bool ldm_parse_vol5(const u8 *buffer, int buflen, struct vblk *vb)
1074{
1075        int r_objid, r_name, r_vtype, r_disable_drive_letter, r_child, r_size;
1076        int r_id1, r_id2, r_size2, r_drive, len;
1077        struct vblk_volu *volu;
1078
1079        BUG_ON(!buffer || !vb);
1080        r_objid = ldm_relative(buffer, buflen, 0x18, 0);
1081        if (r_objid < 0) {
1082                ldm_error("r_objid %d < 0", r_objid);
1083                return false;
1084        }
1085        r_name = ldm_relative(buffer, buflen, 0x18, r_objid);
1086        if (r_name < 0) {
1087                ldm_error("r_name %d < 0", r_name);
1088                return false;
1089        }
1090        r_vtype = ldm_relative(buffer, buflen, 0x18, r_name);
1091        if (r_vtype < 0) {
1092                ldm_error("r_vtype %d < 0", r_vtype);
1093                return false;
1094        }
1095        r_disable_drive_letter = ldm_relative(buffer, buflen, 0x18, r_vtype);
1096        if (r_disable_drive_letter < 0) {
1097                ldm_error("r_disable_drive_letter %d < 0",
1098                                r_disable_drive_letter);
1099                return false;
1100        }
1101        r_child = ldm_relative(buffer, buflen, 0x2D, r_disable_drive_letter);
1102        if (r_child < 0) {
1103                ldm_error("r_child %d < 0", r_child);
1104                return false;
1105        }
1106        r_size = ldm_relative(buffer, buflen, 0x3D, r_child);
1107        if (r_size < 0) {
1108                ldm_error("r_size %d < 0", r_size);
1109                return false;
1110        }
1111        if (buffer[0x12] & VBLK_FLAG_VOLU_ID1) {
1112                r_id1 = ldm_relative(buffer, buflen, 0x52, r_size);
1113                if (r_id1 < 0) {
1114                        ldm_error("r_id1 %d < 0", r_id1);
1115                        return false;
1116                }
1117        } else
1118                r_id1 = r_size;
1119        if (buffer[0x12] & VBLK_FLAG_VOLU_ID2) {
1120                r_id2 = ldm_relative(buffer, buflen, 0x52, r_id1);
1121                if (r_id2 < 0) {
1122                        ldm_error("r_id2 %d < 0", r_id2);
1123                        return false;
1124                }
1125        } else
1126                r_id2 = r_id1;
1127        if (buffer[0x12] & VBLK_FLAG_VOLU_SIZE) {
1128                r_size2 = ldm_relative(buffer, buflen, 0x52, r_id2);
1129                if (r_size2 < 0) {
1130                        ldm_error("r_size2 %d < 0", r_size2);
1131                        return false;
1132                }
1133        } else
1134                r_size2 = r_id2;
1135        if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
1136                r_drive = ldm_relative(buffer, buflen, 0x52, r_size2);
1137                if (r_drive < 0) {
1138                        ldm_error("r_drive %d < 0", r_drive);
1139                        return false;
1140                }
1141        } else
1142                r_drive = r_size2;
1143        len = r_drive;
1144        if (len < 0) {
1145                ldm_error("len %d < 0", len);
1146                return false;
1147        }
1148        len += VBLK_SIZE_VOL5;
1149        if (len > get_unaligned_be32(buffer + 0x14)) {
1150                ldm_error("len %d > BE32(buffer + 0x14) %d", len,
1151                                get_unaligned_be32(buffer + 0x14));
1152                return false;
1153        }
1154        volu = &vb->vblk.volu;
1155        ldm_get_vstr(buffer + 0x18 + r_name, volu->volume_type,
1156                        sizeof(volu->volume_type));
1157        memcpy(volu->volume_state, buffer + 0x18 + r_disable_drive_letter,
1158                        sizeof(volu->volume_state));
1159        volu->size = ldm_get_vnum(buffer + 0x3D + r_child);
1160        volu->partition_type = buffer[0x41 + r_size];
1161        memcpy(volu->guid, buffer + 0x42 + r_size, sizeof(volu->guid));
1162        if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
1163                ldm_get_vstr(buffer + 0x52 + r_size, volu->drive_hint,
1164                                sizeof(volu->drive_hint));
1165        }
1166        return true;
1167}
1168
1169/**
1170 * ldm_parse_vblk - Read a raw VBLK object into a vblk structure
1171 * @buf:  Block of data being worked on
1172 * @len:  Size of the block of data
1173 * @vb:   In-memory vblk in which to return information
1174 *
1175 * Read a raw VBLK object into a vblk structure.  This function just reads the
1176 * information common to all VBLK types, then delegates the rest of the work to
1177 * helper functions: ldm_parse_*.
1178 *
1179 * Return:  'true'   @vb contains a VBLK
1180 *          'false'  @vb contents are not defined
1181 */
1182static bool ldm_parse_vblk (const u8 *buf, int len, struct vblk *vb)
1183{
1184        bool result = false;
1185        int r_objid;
1186
1187        BUG_ON (!buf || !vb);
1188
1189        r_objid = ldm_relative (buf, len, 0x18, 0);
1190        if (r_objid < 0) {
1191                ldm_error ("VBLK header is corrupt.");
1192                return false;
1193        }
1194
1195        vb->flags  = buf[0x12];
1196        vb->type   = buf[0x13];
1197        vb->obj_id = ldm_get_vnum (buf + 0x18);
1198        ldm_get_vstr (buf+0x18+r_objid, vb->name, sizeof (vb->name));
1199
1200        switch (vb->type) {
1201                case VBLK_CMP3:  result = ldm_parse_cmp3 (buf, len, vb); break;
1202                case VBLK_DSK3:  result = ldm_parse_dsk3 (buf, len, vb); break;
1203                case VBLK_DSK4:  result = ldm_parse_dsk4 (buf, len, vb); break;
1204                case VBLK_DGR3:  result = ldm_parse_dgr3 (buf, len, vb); break;
1205                case VBLK_DGR4:  result = ldm_parse_dgr4 (buf, len, vb); break;
1206                case VBLK_PRT3:  result = ldm_parse_prt3 (buf, len, vb); break;
1207                case VBLK_VOL5:  result = ldm_parse_vol5 (buf, len, vb); break;
1208        }
1209
1210        if (result)
1211                ldm_debug ("Parsed VBLK 0x%llx (type: 0x%02x) ok.",
1212                         (unsigned long long) vb->obj_id, vb->type);
1213        else
1214                ldm_error ("Failed to parse VBLK 0x%llx (type: 0x%02x).",
1215                        (unsigned long long) vb->obj_id, vb->type);
1216
1217        return result;
1218}
1219
1220
1221/**
1222 * ldm_ldmdb_add - Adds a raw VBLK entry to the ldmdb database
1223 * @data:  Raw VBLK to add to the database
1224 * @len:   Size of the raw VBLK
1225 * @ldb:   Cache of the database structures
1226 *
1227 * The VBLKs are sorted into categories.  Partitions are also sorted by offset.
1228 *
1229 * N.B.  This function does not check the validity of the VBLKs.
1230 *
1231 * Return:  'true'   The VBLK was added
1232 *          'false'  An error occurred
1233 */
1234static bool ldm_ldmdb_add (u8 *data, int len, struct ldmdb *ldb)
1235{
1236        struct vblk *vb;
1237        struct list_head *item;
1238
1239        BUG_ON (!data || !ldb);
1240
1241        vb = kmalloc (sizeof (*vb), GFP_KERNEL);
1242        if (!vb) {
1243                ldm_crit ("Out of memory.");
1244                return false;
1245        }
1246
1247        if (!ldm_parse_vblk (data, len, vb)) {
1248                kfree(vb);
1249                return false;                   /* Already logged */
1250        }
1251
1252        /* Put vblk into the correct list. */
1253        switch (vb->type) {
1254        case VBLK_DGR3:
1255        case VBLK_DGR4:
1256                list_add (&vb->list, &ldb->v_dgrp);
1257                break;
1258        case VBLK_DSK3:
1259        case VBLK_DSK4:
1260                list_add (&vb->list, &ldb->v_disk);
1261                break;
1262        case VBLK_VOL5:
1263                list_add (&vb->list, &ldb->v_volu);
1264                break;
1265        case VBLK_CMP3:
1266                list_add (&vb->list, &ldb->v_comp);
1267                break;
1268        case VBLK_PRT3:
1269                /* Sort by the partition's start sector. */
1270                list_for_each (item, &ldb->v_part) {
1271                        struct vblk *v = list_entry (item, struct vblk, list);
1272                        if ((v->vblk.part.disk_id == vb->vblk.part.disk_id) &&
1273                            (v->vblk.part.start > vb->vblk.part.start)) {
1274                                list_add_tail (&vb->list, &v->list);
1275                                return true;
1276                        }
1277                }
1278                list_add_tail (&vb->list, &ldb->v_part);
1279                break;
1280        }
1281        return true;
1282}
1283
1284/**
1285 * ldm_frag_add - Add a VBLK fragment to a list
1286 * @data:   Raw fragment to be added to the list
1287 * @size:   Size of the raw fragment
1288 * @frags:  Linked list of VBLK fragments
1289 *
1290 * Fragmented VBLKs may not be consecutive in the database, so they are placed
1291 * in a list so they can be pieced together later.
1292 *
1293 * Return:  'true'   Success, the VBLK was added to the list
1294 *          'false'  Error, a problem occurred
1295 */
1296static bool ldm_frag_add (const u8 *data, int size, struct list_head *frags)
1297{
1298        struct frag *f;
1299        struct list_head *item;
1300        int rec, num, group;
1301
1302        BUG_ON (!data || !frags);
1303
1304        if (size < 2 * VBLK_SIZE_HEAD) {
1305                ldm_error("Value of size is to small.");
1306                return false;
1307        }
1308
1309        group = get_unaligned_be32(data + 0x08);
1310        rec   = get_unaligned_be16(data + 0x0C);
1311        num   = get_unaligned_be16(data + 0x0E);
1312        if ((num < 1) || (num > 4)) {
1313                ldm_error ("A VBLK claims to have %d parts.", num);
1314                return false;
1315        }
1316        if (rec >= num) {
1317                ldm_error("REC value (%d) exceeds NUM value (%d)", rec, num);
1318                return false;
1319        }
1320
1321        list_for_each (item, frags) {
1322                f = list_entry (item, struct frag, list);
1323                if (f->group == group)
1324                        goto found;
1325        }
1326
1327        f = kmalloc (sizeof (*f) + size*num, GFP_KERNEL);
1328        if (!f) {
1329                ldm_crit ("Out of memory.");
1330                return false;
1331        }
1332
1333        f->group = group;
1334        f->num   = num;
1335        f->rec   = rec;
1336        f->map   = 0xFF << num;
1337
1338        list_add_tail (&f->list, frags);
1339found:
1340        if (rec >= f->num) {
1341                ldm_error("REC value (%d) exceeds NUM value (%d)", rec, f->num);
1342                return false;
1343        }
1344        if (f->map & (1 << rec)) {
1345                ldm_error ("Duplicate VBLK, part %d.", rec);
1346                f->map &= 0x7F;                 /* Mark the group as broken */
1347                return false;
1348        }
1349        f->map |= (1 << rec);
1350        if (!rec)
1351                memcpy(f->data, data, VBLK_SIZE_HEAD);
1352        data += VBLK_SIZE_HEAD;
1353        size -= VBLK_SIZE_HEAD;
1354        memcpy(f->data + VBLK_SIZE_HEAD + rec * size, data, size);
1355        return true;
1356}
1357
1358/**
1359 * ldm_frag_free - Free a linked list of VBLK fragments
1360 * @list:  Linked list of fragments
1361 *
1362 * Free a linked list of VBLK fragments
1363 *
1364 * Return:  none
1365 */
1366static void ldm_frag_free (struct list_head *list)
1367{
1368        struct list_head *item, *tmp;
1369
1370        BUG_ON (!list);
1371
1372        list_for_each_safe (item, tmp, list)
1373                kfree (list_entry (item, struct frag, list));
1374}
1375
1376/**
1377 * ldm_frag_commit - Validate fragmented VBLKs and add them to the database
1378 * @frags:  Linked list of VBLK fragments
1379 * @ldb:    Cache of the database structures
1380 *
1381 * Now that all the fragmented VBLKs have been collected, they must be added to
1382 * the database for later use.
1383 *
1384 * Return:  'true'   All the fragments we added successfully
1385 *          'false'  One or more of the fragments we invalid
1386 */
1387static bool ldm_frag_commit (struct list_head *frags, struct ldmdb *ldb)
1388{
1389        struct frag *f;
1390        struct list_head *item;
1391
1392        BUG_ON (!frags || !ldb);
1393
1394        list_for_each (item, frags) {
1395                f = list_entry (item, struct frag, list);
1396
1397                if (f->map != 0xFF) {
1398                        ldm_error ("VBLK group %d is incomplete (0x%02x).",
1399                                f->group, f->map);
1400                        return false;
1401                }
1402
1403                if (!ldm_ldmdb_add (f->data, f->num*ldb->vm.vblk_size, ldb))
1404                        return false;           /* Already logged */
1405        }
1406        return true;
1407}
1408
1409/**
1410 * ldm_get_vblks - Read the on-disk database of VBLKs into memory
1411 * @state: Partition check state including device holding the LDM Database
1412 * @base:  Offset, into @state->bdev, of the database
1413 * @ldb:   Cache of the database structures
1414 *
1415 * To use the information from the VBLKs, they need to be read from the disk,
1416 * unpacked and validated.  We cache them in @ldb according to their type.
1417 *
1418 * Return:  'true'   All the VBLKs were read successfully
1419 *          'false'  An error occurred
1420 */
1421static bool ldm_get_vblks(struct parsed_partitions *state, unsigned long base,
1422                          struct ldmdb *ldb)
1423{
1424        int size, perbuf, skip, finish, s, v, recs;
1425        u8 *data = NULL;
1426        Sector sect;
1427        bool result = false;
1428        LIST_HEAD (frags);
1429
1430        BUG_ON(!state || !ldb);
1431
1432        size   = ldb->vm.vblk_size;
1433        perbuf = 512 / size;
1434        skip   = ldb->vm.vblk_offset >> 9;              /* Bytes to sectors */
1435        finish = (size * ldb->vm.last_vblk_seq) >> 9;
1436
1437        for (s = skip; s < finish; s++) {               /* For each sector */
1438                data = read_part_sector(state, base + OFF_VMDB + s, &sect);
1439                if (!data) {
1440                        ldm_crit ("Disk read failed.");
1441                        goto out;
1442                }
1443
1444                for (v = 0; v < perbuf; v++, data+=size) {  /* For each vblk */
1445                        if (MAGIC_VBLK != get_unaligned_be32(data)) {
1446                                ldm_error ("Expected to find a VBLK.");
1447                                goto out;
1448                        }
1449
1450                        recs = get_unaligned_be16(data + 0x0E); /* Number of records */
1451                        if (recs == 1) {
1452                                if (!ldm_ldmdb_add (data, size, ldb))
1453                                        goto out;       /* Already logged */
1454                        } else if (recs > 1) {
1455                                if (!ldm_frag_add (data, size, &frags))
1456                                        goto out;       /* Already logged */
1457                        }
1458                        /* else Record is not in use, ignore it. */
1459                }
1460                put_dev_sector (sect);
1461                data = NULL;
1462        }
1463
1464        result = ldm_frag_commit (&frags, ldb); /* Failures, already logged */
1465out:
1466        if (data)
1467                put_dev_sector (sect);
1468        ldm_frag_free (&frags);
1469
1470        return result;
1471}
1472
1473/**
1474 * ldm_free_vblks - Free a linked list of vblk's
1475 * @lh:  Head of a linked list of struct vblk
1476 *
1477 * Free a list of vblk's and free the memory used to maintain the list.
1478 *
1479 * Return:  none
1480 */
1481static void ldm_free_vblks (struct list_head *lh)
1482{
1483        struct list_head *item, *tmp;
1484
1485        BUG_ON (!lh);
1486
1487        list_for_each_safe (item, tmp, lh)
1488                kfree (list_entry (item, struct vblk, list));
1489}
1490
1491
1492/**
1493 * ldm_partition - Find out whether a device is a dynamic disk and handle it
1494 * @state: Partition check state including device holding the LDM Database
1495 *
1496 * This determines whether the device @bdev is a dynamic disk and if so creates
1497 * the partitions necessary in the gendisk structure pointed to by @hd.
1498 *
1499 * We create a dummy device 1, which contains the LDM database, and then create
1500 * each partition described by the LDM database in sequence as devices 2+. For
1501 * example, if the device is hda, we would have: hda1: LDM database, hda2, hda3,
1502 * and so on: the actual data containing partitions.
1503 *
1504 * Return:  1 Success, @state->bdev is a dynamic disk and we handled it
1505 *          0 Success, @state->bdev is not a dynamic disk
1506 *         -1 An error occurred before enough information had been read
1507 *            Or @state->bdev is a dynamic disk, but it may be corrupted
1508 */
1509int ldm_partition(struct parsed_partitions *state)
1510{
1511        struct ldmdb  *ldb;
1512        unsigned long base;
1513        int result = -1;
1514
1515        BUG_ON(!state);
1516
1517        /* Look for signs of a Dynamic Disk */
1518        if (!ldm_validate_partition_table(state))
1519                return 0;
1520
1521        ldb = kmalloc (sizeof (*ldb), GFP_KERNEL);
1522        if (!ldb) {
1523                ldm_crit ("Out of memory.");
1524                goto out;
1525        }
1526
1527        /* Parse and check privheads. */
1528        if (!ldm_validate_privheads(state, &ldb->ph))
1529                goto out;               /* Already logged */
1530
1531        /* All further references are relative to base (database start). */
1532        base = ldb->ph.config_start;
1533
1534        /* Parse and check tocs and vmdb. */
1535        if (!ldm_validate_tocblocks(state, base, ldb) ||
1536            !ldm_validate_vmdb(state, base, ldb))
1537                goto out;               /* Already logged */
1538
1539        /* Initialize vblk lists in ldmdb struct */
1540        INIT_LIST_HEAD (&ldb->v_dgrp);
1541        INIT_LIST_HEAD (&ldb->v_disk);
1542        INIT_LIST_HEAD (&ldb->v_volu);
1543        INIT_LIST_HEAD (&ldb->v_comp);
1544        INIT_LIST_HEAD (&ldb->v_part);
1545
1546        if (!ldm_get_vblks(state, base, ldb)) {
1547                ldm_crit ("Failed to read the VBLKs from the database.");
1548                goto cleanup;
1549        }
1550
1551        /* Finally, create the data partition devices. */
1552        if (ldm_create_data_partitions(state, ldb)) {
1553                ldm_debug ("Parsed LDM database successfully.");
1554                result = 1;
1555        }
1556        /* else Already logged */
1557
1558cleanup:
1559        ldm_free_vblks (&ldb->v_dgrp);
1560        ldm_free_vblks (&ldb->v_disk);
1561        ldm_free_vblks (&ldb->v_volu);
1562        ldm_free_vblks (&ldb->v_comp);
1563        ldm_free_vblks (&ldb->v_part);
1564out:
1565        kfree (ldb);
1566        return result;
1567}
1568
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