wimboot/wimboot-2.7.3/src/vdisk.h

   1 #ifndef _VDISK_H
   2 #define _VDISK_H
   3
   4 /*
   5  * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20  * 02110-1301, USA.
  21  */
  22
  23 /**
  24  * @file
  25  *
  26  * Virtual disk emulation
  27  *
  28  */
  29
  30 #include <stdint.h>
  31
  32 /** Number of cylinders */
  33 #define VDISK_CYLINDERS 1024 /* Maximum possible */
  34
  35 /** Number of heads */
  36 #define VDISK_HEADS 255
  37
  38 /** Number of sectors per track */
  39 #define VDISK_SECTORS_PER_TRACK 63
  40
  41 /** Sector size (in bytes) */
  42 #define VDISK_SECTOR_SIZE 512
  43
  44 /** Partition start LBA */
  45 #define VDISK_PARTITION_LBA 128
  46
  47 /** Cluster size (in sectors) */
  48 #define VDISK_CLUSTER_COUNT 64
  49
  50 /** Cluster size (in bytes) */
  51 #define VDISK_CLUSTER_SIZE ( VDISK_CLUSTER_COUNT * VDISK_SECTOR_SIZE )
  52
  53 /** Number of clusters */
  54 #define VDISK_CLUSTERS 0x03ffc000ULL /* Fill 2TB disk */
  55
  56 /** Maximum number of virtual files
  57  *
  58  * The total number of files must be strictly less than the number of
  59  * sectors per cluster.
  60  */
  61 #define VDISK_MAX_FILES ( VDISK_CLUSTER_COUNT - 1 )
  62
  63 /** Maximum file size (in sectors) */
  64 #define VDISK_FILE_COUNT 0x800000UL /* max for 32-bit address space */
  65
  66 /** Maximum file size (in clusters) */
  67 #define VDISK_FILE_CLUSTERS ( VDISK_FILE_COUNT / VDISK_CLUSTER_COUNT )
  68
  69 /** File starting LBA */
  70 #define VDISK_FILE_LBA( idx ) ( ( (idx) + 1 ) * VDISK_FILE_COUNT )
  71
  72 /** File index from LBA */
  73 #define VDISK_FILE_IDX( lba ) ( ( (lba) / VDISK_FILE_COUNT ) - 1 )
  74
  75 /** File offset (in bytes) from LBA */
  76 #define VDISK_FILE_OFFSET( lba )                                        \
  77         ( ( (lba) % VDISK_FILE_COUNT ) * VDISK_SECTOR_SIZE )
  78
  79 /** File index from directory entry LBA */
  80 #define VDISK_FILE_DIRENT_IDX( lba ) ( ( (lba) - 1 ) % VDISK_CLUSTER_COUNT )
  81
  82 /** Number of sectors allocated for FAT */
  83 #define VDISK_SECTORS_PER_FAT                                           \
  84         ( ( ( VDISK_CLUSTERS * sizeof ( uint32_t ) +                    \
  85               VDISK_CLUSTER_SIZE - 1 ) / VDISK_CLUSTER_SIZE )           \
  86           * VDISK_CLUSTER_COUNT )
  87
  88 /** Number of reserved sectors */
  89 #define VDISK_RESERVED_COUNT VDISK_CLUSTER_COUNT
  90
  91 /** Starting cluster number for file */
  92 #define VDISK_FILE_CLUSTER( idx )                                       \
  93         ( ( ( ( VDISK_FILE_COUNT - VDISK_PARTITION_LBA -                \
  94                 VDISK_RESERVED_COUNT - VDISK_SECTORS_PER_FAT ) /        \
  95               VDISK_CLUSTER_COUNT ) + 2 ) +                             \
  96           ( (idx) * VDISK_FILE_CLUSTERS ) )
  97
  98 /** Total number of sectors within partition */
  99 #define VDISK_PARTITION_COUNT                                           \
 100         ( VDISK_RESERVED_COUNT + VDISK_SECTORS_PER_FAT +                \
 101           ( VDISK_CLUSTERS * VDISK_CLUSTER_COUNT ) )
 102
 103 /** Number of sectors */
 104 #define VDISK_COUNT ( VDISK_PARTITION_LBA + VDISK_PARTITION_COUNT )
 105
 106 /** Calculate sector from cluster */
 107 #define VDISK_CLUSTER_SECTOR( cluster )                                 \
 108         ( ( ( (cluster) - 2 ) * VDISK_CLUSTER_COUNT ) +                 \
 109           VDISK_RESERVED_COUNT + VDISK_SECTORS_PER_FAT )
 110
 111 /*****************************************************************************
 112  *
 113  * Master Boot Record
 114  *
 115  *****************************************************************************
 116  */
 117
 118 /** Master Boot Record LBA */
 119 #define VDISK_MBR_LBA 0x00000000
 120
 121 /** Master Boot Record sector count */
 122 #define VDISK_MBR_COUNT 1
 123
 124 /** Partition table entry */
 125 struct vdisk_partition {
 126         /** Bootable flag */
 127         uint8_t bootable;
 128         /** C/H/S start address */
 129         uint8_t chs_start[3];
 130         /** System indicator (partition type) */
 131         uint8_t type;
 132         /** C/H/S end address */
 133         uint8_t chs_end[3];
 134         /** Linear start address */
 135         uint32_t start;
 136         /** Linear length */
 137         uint32_t length;
 138 } __attribute__ (( packed ));
 139
 140 /** Master Boot Record */
 141 struct vdisk_mbr {
 142         /** Code area */
 143         uint8_t code[440];
 144         /** Disk signature */
 145         uint32_t signature;
 146         /** Padding */
 147         uint8_t pad[2];
 148         /** Partition table */
 149         struct vdisk_partition partitions[4];
 150         /** 0x55aa signature */
 151         uint16_t magic;
 152 } __attribute__ (( packed ));
 153
 154 /** MBR boot partition indiciator */
 155 #define VDISK_MBR_BOOTABLE 0x80
 156
 157 /** MBR type indicator for FAT32 */
 158 #define VDISK_MBR_TYPE_FAT32 0x0c
 159
 160 /** MBR signature */
 161 #define VDISK_MBR_SIGNATURE 0xc0ffeeee
 162
 163 /** MBR magic */
 164 #define VDISK_MBR_MAGIC 0xaa55
 165
 166 /*****************************************************************************
 167  *
 168  * Volume Boot Record
 169  *
 170  *****************************************************************************
 171  */
 172
 173 /** Volume Boot Record LBA */
 174 #define VDISK_VBR_LBA VDISK_PARTITION_LBA
 175
 176 /** Volume Boot Record sector count */
 177 #define VDISK_VBR_COUNT 1
 178
 179 /** Volume Boot Record */
 180 struct vdisk_vbr {
 181         /** Jump instruction */
 182         uint8_t jump[3];
 183         /** OEM identifier */
 184         char oemid[8];
 185         /** Number of bytes per sector */
 186         uint16_t bytes_per_sector;
 187         /** Number of sectors per cluster */
 188         uint8_t sectors_per_cluster;
 189         /** Number of reserved sectors */
 190         uint16_t reserved_sectors;
 191         /** Number of FATs */
 192         uint8_t fats;
 193         /** Number of root directory entries (FAT12/FAT16 only) */
 194         uint16_t root_directory_entries;
 195         /** Total number of sectors (0 if more than 65535) */
 196         uint16_t sectors_short;
 197         /** Media descriptor type */
 198         uint8_t media;
 199         /** Number of sectors per FAT (FAT12/FAT16 only) */
 200         uint16_t sectors_per_fat_short;
 201         /** Number of sectors per track */
 202         uint16_t sectors_per_track;
 203         /** Number of heads */
 204         uint16_t heads;
 205         /** Number of hidden sectors (i.e. LBA of start of partition) */
 206         uint32_t hidden_sectors;
 207         /** Total number of sectors */
 208         uint32_t sectors;
 209
 210         /* FAT32-specific fields */
 211
 212         /** Sectors per FAT */
 213         uint32_t sectors_per_fat;
 214         /** Flags */
 215         uint16_t flags;
 216         /** FAT version number */
 217         uint16_t version;
 218         /** Root directory cluster */
 219         uint32_t root;
 220         /** FSInfo sector */
 221         uint16_t fsinfo;
 222         /** Backup boot sector */
 223         uint16_t backup;
 224         /** Reserved */
 225         uint8_t reserved[12];
 226         /** Drive number */
 227         uint8_t drive;
 228         /** Windows NT flags */
 229         uint8_t nt_flags;
 230         /** Signature */
 231         uint8_t signature;
 232         /** Volume ID serial */
 233         uint32_t serial;
 234         /** Label (space-padded) */
 235         char label[11];
 236         /** System identifier */
 237         char system[8];
 238         /** Boot code */
 239         uint8_t code[420];
 240         /** 0x55aa signature */
 241         uint16_t magic;
 242 } __attribute__ (( packed ));
 243
 244 /** VBR jump instruction
 245  *
 246  * bootmgr.exe will actually fail unless this is present.  Someone
 247  * must read specification documents without bothering to understand
 248  * what's really happening.
 249  */
 250 #define VDISK_VBR_JUMP_WTF_MS 0xe9
 251
 252 /** VBR OEM ID */
 253 #define VDISK_VBR_OEMID "wimboot\0"
 254
 255 /** VBR media type */
 256 #define VDISK_VBR_MEDIA 0xf8
 257
 258 /** VBR signature */
 259 #define VDISK_VBR_SIGNATURE 0x29
 260
 261 /** VBR serial number */
 262 #define VDISK_VBR_SERIAL 0xf00df00d
 263
 264 /** VBR label */
 265 #define VDISK_VBR_LABEL "wimboot    "
 266
 267 /** VBR system identifier */
 268 #define VDISK_VBR_SYSTEM "FAT32   "
 269
 270 /** VBR magic */
 271 #define VDISK_VBR_MAGIC 0xaa55
 272
 273 /*****************************************************************************
 274  *
 275  * FSInfo
 276  *
 277  *****************************************************************************
 278  */
 279
 280 /** FSInfo sector */
 281 #define VDISK_FSINFO_SECTOR 0x00000001
 282
 283 /** FSInfo LBA */
 284 #define VDISK_FSINFO_LBA ( VDISK_VBR_LBA + VDISK_FSINFO_SECTOR )
 285
 286 /** FSInfo sector count */
 287 #define VDISK_FSINFO_COUNT 1
 288
 289 /** FSInfo */
 290 struct vdisk_fsinfo {
 291         /** First signature */
 292         uint32_t magic1;
 293         /** Reserved */
 294         uint8_t reserved_1[480];
 295         /** Second signature */
 296         uint32_t magic2;
 297         /** Free cluster count */
 298         uint32_t free_count;
 299         /** Next free cluster */
 300         uint32_t next_free;
 301         /** Reserved */
 302         uint8_t reserved_2[12];
 303         /** Third signature */
 304         uint32_t magic3;
 305 } __attribute__ (( packed ));
 306
 307 /** FSInfo first signature */
 308 #define VDISK_FSINFO_MAGIC1 0x41615252
 309
 310 /** FSInfo second signature */
 311 #define VDISK_FSINFO_MAGIC2 0x61417272
 312
 313 /** FSInfo next free cluster */
 314 #define VDISK_FSINFO_NEXT_FREE 0xffffffff /* No free clusters */
 315
 316 /** FSInfo third signature */
 317 #define VDISK_FSINFO_MAGIC3 0xaa550000
 318
 319 /*****************************************************************************
 320  *
 321  * Backup Volume Boot Record
 322  *
 323  *****************************************************************************
 324  */
 325
 326 /** Backup Volume Boot Record sector */
 327 #define VDISK_BACKUP_VBR_SECTOR 0x00000006
 328
 329 /** Backup Volume Boot Record LBA */
 330 #define VDISK_BACKUP_VBR_LBA ( VDISK_VBR_LBA + VDISK_BACKUP_VBR_SECTOR )
 331
 332 /** Backup Volume Boot Record sector count */
 333 #define VDISK_BACKUP_VBR_COUNT 1
 334
 335 /*****************************************************************************
 336  *
 337  * File Allocation Table
 338  *
 339  *****************************************************************************
 340  */
 341
 342 /** FAT sector */
 343 #define VDISK_FAT_SECTOR VDISK_RESERVED_COUNT
 344
 345 /** FAT LBA */
 346 #define VDISK_FAT_LBA ( VDISK_VBR_LBA + VDISK_FAT_SECTOR )
 347
 348 /** FAT sector count */
 349 #define VDISK_FAT_COUNT VDISK_SECTORS_PER_FAT
 350
 351 /** FAT end marker */
 352 #define VDISK_FAT_END_MARKER 0x0ffffff8
 353
 354 /*****************************************************************************
 355  *
 356  * Directory entries
 357  *
 358  *****************************************************************************
 359  */
 360
 361 /** An 8.3 filename record */
 362 struct vdisk_short_filename {
 363         /** Filename */
 364         union {
 365                 /** Structured 8.3 base name and extension */
 366                 struct {
 367                         /** Base name */
 368                         char base[8];
 369                         /** Extension */
 370                         char ext[3];
 371                 } __attribute__ (( packed ));
 372                 /** Raw bytes */
 373                 uint8_t raw[11];
 374         } filename;
 375         /** Attributes */
 376         uint8_t attr;
 377         /** Reserved */
 378         uint8_t reserved;
 379         /** Creation time in tenths of a second */
 380         uint8_t created_deciseconds;
 381         /** Creation time (HMS packed) */
 382         uint16_t created_time;
 383         /** Creation date (YMD packed) */
 384         uint16_t created_date;
 385         /** Last accessed date (YMD packed) */
 386         uint16_t accessed_date;
 387         /** High 16 bits of starting cluster number */
 388         uint16_t cluster_high;
 389         /** Modification time (HMS packed) */
 390         uint16_t modified_time;
 391         /** Modification date (YMD packed) */
 392         uint16_t modified_date;
 393         /** Low 16 bits of starting cluster number */
 394         uint16_t cluster_low;
 395         /** Size */
 396         uint32_t size;
 397 } __attribute__ (( packed ));
 398
 399 /** A long filename record */
 400 struct vdisk_long_filename {
 401         /** Sequence number */
 402         uint8_t sequence;
 403         /** Name characters */
 404         uint16_t name_1[5];
 405         /** Attributes */
 406         uint8_t attr;
 407         /** Type */
 408         uint8_t type;
 409         /** Checksum of 8.3 name */
 410         uint8_t checksum;
 411         /** Name characters */
 412         uint16_t name_2[6];
 413         /** Reserved */
 414         uint16_t reserved;
 415         /** Name characters */
 416         uint16_t name_3[2];
 417 } __attribute__ (( packed ));
 418
 419 /** Directory entry attributes */
 420 enum vdisk_directory_entry_attributes {
 421         VDISK_READ_ONLY = 0x01,
 422         VDISK_HIDDEN = 0x02,
 423         VDISK_SYSTEM = 0x04,
 424         VDISK_VOLUME_LABEL = 0x08,
 425         VDISK_DIRECTORY = 0x10,
 426 };
 427
 428 /** Long filename end-of-sequence marker */
 429 #define VDISK_LFN_END 0x40
 430
 431 /** Long filename attributes */
 432 #define VDISK_LFN_ATTR \
 433         ( VDISK_READ_ONLY | VDISK_HIDDEN | VDISK_SYSTEM | VDISK_VOLUME_LABEL )
 434
 435 /** A directory entry */
 436 union vdisk_directory_entry {
 437         /** Deleted file marker */
 438         uint8_t deleted;
 439         /** 8.3 filename */
 440         struct vdisk_short_filename dos;
 441         /** Long filename */
 442         struct vdisk_long_filename lfn;
 443 } __attribute__ (( packed ));
 444
 445 /** Magic marker for deleted files */
 446 #define VDISK_DIRENT_DELETED 0xe5
 447
 448 /** Number of directory entries per sector */
 449 #define VDISK_DIRENT_PER_SECTOR                                 \
 450         ( VDISK_SECTOR_SIZE /                                   \
 451           sizeof ( union vdisk_directory_entry ) )
 452
 453 /** A directory sector */
 454 struct vdisk_directory {
 455         /** Entries */
 456         union vdisk_directory_entry entry[VDISK_DIRENT_PER_SECTOR];
 457 } __attribute__ (( packed ));
 458
 459 /*****************************************************************************
 460  *
 461  * Root directory
 462  *
 463  *****************************************************************************
 464  */
 465
 466 /** Root directory cluster */
 467 #define VDISK_ROOT_CLUSTER 2
 468
 469 /** Root directory sector */
 470 #define VDISK_ROOT_SECTOR VDISK_CLUSTER_SECTOR ( VDISK_ROOT_CLUSTER )
 471
 472 /** Root directory LBA */
 473 #define VDISK_ROOT_LBA ( VDISK_VBR_LBA + VDISK_ROOT_SECTOR )
 474
 475 /*****************************************************************************
 476  *
 477  * Boot directory
 478  *
 479  *****************************************************************************
 480  */
 481
 482 /** Boot directory cluster */
 483 #define VDISK_BOOT_CLUSTER 3
 484
 485 /** Boot directory sector */
 486 #define VDISK_BOOT_SECTOR VDISK_CLUSTER_SECTOR ( VDISK_BOOT_CLUSTER )
 487
 488 /** Boot directory LBA */
 489 #define VDISK_BOOT_LBA ( VDISK_VBR_LBA + VDISK_BOOT_SECTOR )
 490
 491 /*****************************************************************************
 492  *
 493  * Sources directory
 494  *
 495  *****************************************************************************
 496  */
 497
 498 /** Sources directory cluster */
 499 #define VDISK_SOURCES_CLUSTER 4
 500
 501 /** Sources directory sector */
 502 #define VDISK_SOURCES_SECTOR VDISK_CLUSTER_SECTOR ( VDISK_SOURCES_CLUSTER )
 503
 504 /** Sources directory LBA */
 505 #define VDISK_SOURCES_LBA ( VDISK_VBR_LBA + VDISK_SOURCES_SECTOR )
 506
 507 /*****************************************************************************
 508  *
 509  * Fonts directory
 510  *
 511  *****************************************************************************
 512  */
 513
 514 /** Fonts directory cluster */
 515 #define VDISK_FONTS_CLUSTER 5
 516
 517 /** Fonts directory sector */
 518 #define VDISK_FONTS_SECTOR VDISK_CLUSTER_SECTOR ( VDISK_FONTS_CLUSTER )
 519
 520 /** Fonts directory LBA */
 521 #define VDISK_FONTS_LBA ( VDISK_VBR_LBA + VDISK_FONTS_SECTOR )
 522
 523 /*****************************************************************************
 524  *
 525  * Resources directory
 526  *
 527  *****************************************************************************
 528  */
 529
 530 /** Resources directory cluster */
 531 #define VDISK_RESOURCES_CLUSTER 6
 532
 533 /** Resources directory sector */
 534 #define VDISK_RESOURCES_SECTOR VDISK_CLUSTER_SECTOR ( VDISK_RESOURCES_CLUSTER )
 535
 536 /** Resources directory LBA */
 537 #define VDISK_RESOURCES_LBA ( VDISK_VBR_LBA + VDISK_RESOURCES_SECTOR )
 538
 539 /*****************************************************************************
 540  *
 541  * EFI directory
 542  *
 543  *****************************************************************************
 544  */
 545
 546 /** EFI directory cluster */
 547 #define VDISK_EFI_CLUSTER 7
 548
 549 /** EFI directory sector */
 550 #define VDISK_EFI_SECTOR VDISK_CLUSTER_SECTOR ( VDISK_EFI_CLUSTER )
 551
 552 /** EFI directory LBA */
 553 #define VDISK_EFI_LBA ( VDISK_VBR_LBA + VDISK_EFI_SECTOR )
 554
 555 /*****************************************************************************
 556  *
 557  * Microsoft directory
 558  *
 559  *****************************************************************************
 560  */
 561
 562 /** Microsoft directory cluster */
 563 #define VDISK_MICROSOFT_CLUSTER 8
 564
 565 /** Microsoft directory sector */
 566 #define VDISK_MICROSOFT_SECTOR VDISK_CLUSTER_SECTOR ( VDISK_MICROSOFT_CLUSTER )
 567
 568 /** Microsoft directory LBA */
 569 #define VDISK_MICROSOFT_LBA ( VDISK_VBR_LBA + VDISK_MICROSOFT_SECTOR )
 570
 571 /*****************************************************************************
 572  *
 573  * Files
 574  *
 575  *****************************************************************************
 576  */
 577
 578 /** Maximum virtual filename length (excluding NUL) */
 579 #define VDISK_NAME_LEN 31
 580
 581 /** A virtual file */
 582 struct vdisk_file {
 583         /** Filename */
 584         char name[ VDISK_NAME_LEN + 1 /* NUL */ ];
 585         /** Opaque token */
 586         void *opaque;
 587         /** Length (excluding any zero-padding) */
 588         size_t len;
 589         /** Length (including any zero-padding) */
 590         size_t xlen;
 591         /** Read data
 592          *
 593          * @v file              Virtual file
 594          * @v data              Data buffer
 595          * @v offset            Starting offset
 596          * @v len               Length
 597          */
 598         void ( * read ) ( struct vdisk_file *file, void *data, size_t offset,
 599                           size_t len );
 600         /** Patch data (optional)
 601          *
 602          * @v file              Virtual file
 603          * @v data              Data buffer
 604          * @v offset            Starting offset
 605          * @v len               Length
 606          */
 607         void ( * patch ) ( struct vdisk_file *file, void *data, size_t offset,
 608                            size_t len );
 609 };
 610
 611 extern struct vdisk_file vdisk_files[VDISK_MAX_FILES];
 612
 613 extern void vdisk_read ( uint64_t lba, unsigned int count, void *data );
 614 extern struct vdisk_file *
 615 vdisk_add_file ( const char *name, void *opaque, size_t len,
 616                  void ( * read ) ( struct vdisk_file *file, void *data,
 617                                    size_t offset, size_t len ) );
 618 extern void
 619 vdisk_patch_file ( struct vdisk_file *file,
 620                    void ( * patch ) ( struct vdisk_file *file, void *data,
 621                                       size_t offset, size_t len ) );
 622
 623 #endif /* _VDISK_H */