rom/partition/partitionmbr.c

   1 /*
   2     Copyright © 1995-2017, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <exec/memory.h>
   7 #include <exec/types.h>
   8 #include <libraries/partition.h>
   9 #include <proto/exec.h>
  10 #include <proto/partition.h>
  11 #include <proto/utility.h>
  12
  13 #include "partition_types.h"
  14 #include "partition_support.h"
  15 #include "partitionmbr.h"
  16 #include "platform.h"
  17 #include "debug.h"
  18
  19 struct MBRData {
  20     struct PCPartitionTable *entry;
  21     UBYTE position;
  22 };
  23
  24 struct FATBootSector {
  25     UBYTE bs_jmp_boot[3];
  26     UBYTE bs_oem_name[8];
  27     UWORD bpb_bytes_per_sect;
  28     UBYTE bpb_sect_per_clust;
  29     UWORD bpb_rsvd_sect_count;
  30     UBYTE bpb_num_fats;
  31     UWORD bpb_root_entries_count;
  32     UWORD bpb_total_sectors_16;
  33     UBYTE bpb_media;
  34     UWORD bpb_fat_size_16;
  35     UWORD bpb_sect_per_track;
  36     UWORD bpb_num_heads;
  37     ULONG bpb_hidden_sect;
  38     ULONG bpb_total_sectors_32;
  39
  40     union {
  41         struct {
  42             UBYTE bs_drvnum;
  43             UBYTE bs_reserved1;
  44             UBYTE bs_bootsig;
  45             ULONG bs_volid;
  46             UBYTE bs_vollab[11];
  47             UBYTE bs_filsystype[8];
  48         } __packed fat16;
  49
  50         struct {
  51             ULONG bpb_fat_size_32;
  52             UWORD bpb_extflags;
  53             UWORD bpb_fs_verion;
  54             ULONG bpb_root_cluster;
  55             UWORD bpb_fs_info;
  56             UWORD bpb_back_bootsec;
  57             UBYTE bpb_reserved[12];
  58             UBYTE bs_drvnum;
  59             UBYTE bs_reserved1;
  60             UBYTE bs_bootsig;
  61             ULONG bs_volid;
  62             UBYTE bs_vollab[11];
  63             UBYTE bs_filsystype[8];
  64         } __packed fat32;
  65     } type;
  66     UBYTE pad[420];
  67     UBYTE bpb_signature[2];
  68 } __packed;
  69
  70 struct rootblock
  71 {
  72     union
  73     {
  74         struct MBR mbr;
  75         struct FATBootSector bs;
  76     }
  77     u;
  78 };
  79
  80 LONG MBRCheckPartitionTable(struct Library *PartitionBase, struct PartitionHandle *root, void *buffer)
  81 {
  82     struct rootblock *blk = buffer;
  83     LONG res = 0;
  84
  85     if (readBlock(PartitionBase, root, 0, blk) == 0)
  86     {
  87         /* Check it doesn't look like a FAT boot sector */
  88         ULONG sectorsize, clustersectors;
  89
  90         /* Valid sector size: 512, 1024, 2048, 4096 */
  91         sectorsize = AROS_LE2WORD(blk->u.bs.bpb_bytes_per_sect);
  92         if (sectorsize != 512 && sectorsize != 1024 && sectorsize != 2048 && sectorsize != 4096)
  93             res = 1;
  94
  95         /* Valid bpb_sect_per_clust: 1, 2, 4, 8, 16, 32, 64, 128 */
  96         clustersectors = blk->u.bs.bpb_sect_per_clust;
  97         if ((clustersectors & (clustersectors - 1)) != 0 || clustersectors == 0 || clustersectors > 128)
  98             res = 1;
  99
 100         /* Valid cluster size: 512, 1024, 2048, 4096, 8192, 16k, 32k, 64k */
 101         if (clustersectors * sectorsize > 64 * 1024)
 102             res = 1;
 103
 104         if (blk->u.bs.bpb_media < 0xF0)
 105             res = 1;
 106
 107         if (res)
 108         {
 109             struct PCPartitionTable *pcpt = blk->u.mbr.pcpt;
 110
 111             /* Check status bytes of all partition slots and block signature */
 112             if ((AROS_LE2WORD(blk->u.mbr.magic) != MBR_MAGIC) ||
 113                 (!MBR_STATUS_VALID(pcpt[0].status)) || (!MBR_STATUS_VALID(pcpt[1].status)) ||
 114                 (!MBR_STATUS_VALID(pcpt[2].status)) || (!MBR_STATUS_VALID(pcpt[3].status)))
 115             {
 116                 res = 0;
 117             }
 118         }
 119     }
 120
 121     return res;
 122 }
 123
 124 static LONG PartitionMBRCheckPartitionTable(struct Library *PartitionBase, struct PartitionHandle *root)
 125 {
 126     LONG res;
 127     void *blk;
 128
 129     /* MBR can be placed only in the root of the disk */
 130     if (root->root)
 131         return 0;
 132
 133     blk = AllocMem(root->de.de_SizeBlock << 2, MEMF_ANY);
 134     if (!blk)
 135         return 0;
 136
 137     res = MBRCheckPartitionTable(PartitionBase, root, blk);
 138
 139     FreeMem(blk, root->de.de_SizeBlock << 2);
 140     return res;
 141 }
 142
 143 static struct PartitionHandle *PartitionMBRNewHandle(struct Library *PartitionBase, struct PartitionHandle *root, UBYTE position, struct PCPartitionTable *entry)
 144 {
 145     struct PartitionHandle *ph;
 146
 147     if (entry->first_sector != 0)
 148     {
 149         ph = AllocMem(sizeof(struct PartitionHandle), MEMF_PUBLIC | MEMF_CLEAR);
 150         if (ph)
 151         {
 152         struct MBRData *data;
 153
 154             data = AllocMem(sizeof(struct MBRData), MEMF_PUBLIC);
 155             if (data)
 156             {
 157                 data->entry    = entry;
 158                 data->position = position;
 159                 ph->data = data;
 160
 161                 /* initialize DosEnvec and DriveGeometry */
 162                 initPartitionHandle(root, ph, AROS_LE2LONG(data->entry->first_sector), AROS_LE2LONG(data->entry->count_sector));
 163
 164                 /* Map type ID to a DOSType */
 165                 setDosType(&ph->de, MBR_FindDosType(data->entry->type));
 166
 167                 /* Set position as priority */
 168                 ph->ln.ln_Pri = MBR_MAX_PARTITIONS - 1 - position;
 169                 return ph;
 170             }
 171             FreeMem(ph, sizeof(struct PartitionHandle));
 172         }
 173     }
 174     return NULL;
 175 }
 176
 177 static LONG PartitionMBROpenPartitionTable(struct Library *PartitionBase, struct PartitionHandle *root)
 178 {
 179     struct PartitionHandle *ph;
 180     struct MBR *mbr;
 181     UBYTE i;
 182
 183     mbr = AllocMem(root->de.de_SizeBlock<<2, MEMF_PUBLIC);
 184     if (mbr)
 185     {
 186         if (readBlock(PartitionBase, root, 0, mbr) == 0)
 187         {
 188             root->table->data = mbr;
 189             for (i=0;i<4;i++)
 190             {
 191                 ph = PartitionMBRNewHandle(PartitionBase, root, i, &mbr->pcpt[i]);
 192                 if (ph != NULL)
 193                     Enqueue(&root->table->list, &ph->ln);
 194             }
 195             return 0;
 196         }
 197         FreeMem(mbr, root->de.de_SizeBlock<<2);
 198     }
 199     return 1;
 200 }
 201
 202 static void PartitionMBRFreeHandle
 203     (
 204         struct Library *PartitionBase,
 205         struct PartitionHandle *ph
 206     )
 207 {
 208     ClosePartitionTable(ph);
 209     FreeMem(ph->data, sizeof(struct MBRData));
 210     FreeMem(ph, sizeof(struct PartitionHandle));
 211 }
 212
 213 static void PartitionMBRClosePartitionTable
 214     (
 215         struct Library *PartitionBase,
 216         struct PartitionHandle *root
 217     )
 218 {
 219 struct PartitionHandle *ph;
 220
 221     while ((ph = (struct PartitionHandle *)RemTail(&root->table->list)))
 222         PartitionMBRFreeHandle(PartitionBase, ph);
 223     FreeMem(root->table->data, root->de.de_SizeBlock<<2);
 224 }
 225
 226 static LONG PartitionMBRWritePartitionTable
 227     (
 228         struct Library *PartitionBase,
 229         struct PartitionHandle *root
 230     )
 231 {
 232     /* FIXME: readBlock(0) and synchronize data */
 233
 234     /* root->data = mbr is up to date */
 235     if (writeBlock(PartitionBase, root, 0, root->table->data))
 236         return 1;
 237     return 0;
 238 }
 239
 240 static LONG PartitionMBRCreatePartitionTable
 241     (
 242         struct Library *PartitionBase,
 243         struct PartitionHandle *ph
 244     )
 245 {
 246 struct MBR *mbr;
 247
 248     mbr = AllocMem(ph->de.de_SizeBlock<<2, MEMF_PUBLIC);
 249     if (mbr)
 250     {
 251         if (readBlock(PartitionBase, ph, 0, mbr) == 0)
 252         {
 253             ph->table->data = mbr;
 254
 255             memset(mbr->pcpt, 0, sizeof(mbr->pcpt));
 256             mbr->magic = AROS_WORD2LE(0xAA55);
 257
 258             NEWLIST(&ph->table->list);
 259             return 0;
 260         }
 261         FreeMem(mbr, ph->de.de_SizeBlock<<2);
 262     }
 263     return 1;
 264 }
 265
 266 void PartitionMBRSetGeometry
 267     (
 268         struct PartitionHandle *root,
 269         struct PCPartitionTable *entry,
 270         ULONG sector,
 271         ULONG count,
 272         ULONG relative_sector
 273     )
 274 {
 275 ULONG track;
 276 ULONG cyl;
 277
 278     /* Store LBA start block and block count */
 279
 280     entry->first_sector = AROS_LONG2LE(sector - relative_sector);
 281     entry->count_sector = AROS_LONG2LE(count);
 282
 283     /* Store CHS-address of start block. The upper two bits of the cylinder
 284        number are stored in the upper two bits of the sector field */
 285
 286     track = sector/root->de.de_BlocksPerTrack;
 287     cyl = track/root->de.de_Surfaces;
 288     if (cyl<1024)
 289     {
 290         entry->start_head = track % root->de.de_Surfaces;
 291         entry->start_sector =
 292             ((sector % root->de.de_BlocksPerTrack) + 1)
 293             | ((cyl & 0x300) >> 2);
 294         entry->start_cylinder = (cyl & 0xFF);
 295     }
 296     else
 297     {
 298         entry->start_head = 0xFE;
 299         entry->start_sector = 0xFF;
 300         entry->start_cylinder = 0xFF;
 301     }
 302
 303     /* Store CHS-address of last block */
 304
 305     sector += count - 1;
 306     track = sector/root->de.de_BlocksPerTrack;
 307     cyl = track/root->de.de_Surfaces;
 308     if (cyl<1024)
 309     {
 310         entry->end_head = track % root->de.de_Surfaces;
 311         entry->end_sector = ((sector % root->de.de_BlocksPerTrack) + 1)
 312             | ((cyl & 0x300)>>2);
 313         entry->end_cylinder = (cyl & 0xFF);
 314     }
 315     else
 316     {
 317         entry->end_head = 0xFE;
 318         entry->end_sector = 0xFF;
 319         entry->end_cylinder = 0xFF;
 320     }
 321 }
 322
 323 static void PartitionMBRSetDosEnvec
 324     (
 325         struct PartitionHandle *root,
 326         struct PCPartitionTable *entry,
 327         struct DosEnvec *de
 328     )
 329 {
 330 ULONG sector, count;
 331
 332     sector = de->de_LowCyl * de->de_Surfaces * de->de_BlocksPerTrack;
 333     count = (de->de_HighCyl - de->de_LowCyl + 1) *
 334             de->de_Surfaces *
 335             de->de_BlocksPerTrack;
 336     PartitionMBRSetGeometry(root, entry, sector, count, 0);
 337 }
 338
 339 static struct PartitionHandle *PartitionMBRAddPartition(struct Library *PartitionBase, struct PartitionHandle *root, const struct TagItem *taglist)
 340 {
 341     struct TagItem *tag;
 342
 343     tag = FindTagItem(PT_DOSENVEC, taglist);
 344
 345     if (tag)
 346     {
 347         struct PCPartitionTable *entry;
 348         struct PartitionHandle *ph;
 349         struct DosEnvec *de = (struct DosEnvec *)tag->ti_Data;
 350         WORD pos = -1, i;
 351
 352         tag = FindTagItem(PT_POSITION, taglist);
 353         if (tag != NULL)
 354             pos = tag->ti_Data;
 355         else
 356         {
 357             // Find an unused slot
 358             for (i = 0; i < MBR_MAX_PARTITIONS && pos == -1; i++)
 359             {
 360                 entry = &((struct MBR *)root->table->data)->pcpt[i];
 361                 if (entry->type == 0)
 362                     pos = i;
 363             }
 364         }
 365
 366         if (pos != -1)
 367         {
 368             entry = &((struct MBR *)root->table->data)->pcpt[pos];
 369             tag = FindTagItem(PT_ACTIVE, taglist);
 370             if (tag)
 371                 entry->status = tag->ti_Data ? 0x80 : 0;
 372             else
 373                 entry->status = 0;
 374             tag = FindTagItem(PT_TYPE, taglist);
 375             if (tag)
 376             {
 377             struct PartitionType *ptype = (struct PartitionType *)tag->ti_Data;
 378
 379                 entry->type = ptype->id[0];
 380             }
 381             else
 382                 entry->type = 0;
 383             PartitionMBRSetDosEnvec(root, entry, de);
 384             ph = PartitionMBRNewHandle(PartitionBase, root, pos, entry);
 385             if (ph != NULL)
 386                 Enqueue(&root->table->list, &ph->ln);
 387             else
 388                 memset(entry, 0, sizeof(struct PCPartitionTable));
 389
 390             return ph;
 391         }
 392     }
 393     return NULL;
 394 }
 395
 396 static void PartitionMBRDeletePartition(struct Library *PartitionBase, struct PartitionHandle *ph)
 397 {
 398     struct MBRData *data = (struct MBRData *)ph->data;
 399
 400     memset(data->entry, 0, sizeof(struct PCPartitionTable));
 401
 402     Remove(&ph->ln);
 403     PartitionMBRFreeHandle(PartitionBase, ph);
 404 }
 405
 406 static LONG PartitionMBRGetPartitionTableAttr(struct Library *PartitionBase,
 407     struct PartitionHandle *root, const struct TagItem *tag)
 408 {
 409     switch (tag->ti_Tag)
 410     {
 411     case PTT_RESERVED:
 412         *((LONG *)tag->ti_Data) = root->de.de_BlocksPerTrack; /* One track */
 413         return TRUE;
 414
 415     case PTT_MAX_PARTITIONS:
 416         *((LONG *)tag->ti_Data) = MBR_MAX_PARTITIONS;
 417         return TRUE;
 418     }
 419
 420     return 0;
 421 }
 422
 423 static LONG PartitionMBRGetPartitionAttr(struct Library *PartitionBase,
 424     struct PartitionHandle *ph, const struct TagItem *tag)
 425 {
 426     struct MBRData *data = (struct MBRData *)ph->data;
 427
 428     switch (tag->ti_Tag)
 429     {
 430     case PT_TYPE:
 431         PTYPE(tag->ti_Data)->id[0] = (LONG)data->entry->type;
 432         PTYPE(tag->ti_Data)->id_len = 1;
 433         return TRUE;
 434
 435     case PT_POSITION:
 436         *((LONG *)tag->ti_Data) = (LONG)data->position;
 437         return TRUE;
 438
 439     case PT_ACTIVE:
 440         *((LONG *)tag->ti_Data) = data->entry->status & 0x80 ? 1 : 0;
 441         return TRUE;
 442
 443     case PT_STARTBLOCK:
 444         *((UQUAD *)tag->ti_Data) = AROS_LE2LONG(data->entry->first_sector);
 445         return TRUE;
 446
 447     case PT_ENDBLOCK:
 448         *((UQUAD *)tag->ti_Data) = AROS_LE2LONG(data->entry->first_sector) + AROS_LE2LONG(data->entry->count_sector) - 1;
 449         return TRUE;
 450     }
 451
 452     /* Everything else gets default values */
 453     return 0;
 454 }
 455
 456 static LONG PartitionMBRSetPartitionAttrs(struct Library *PartitionBase, struct PartitionHandle *ph, const struct TagItem *taglist)
 457 {
 458     struct MBRData *data = (struct MBRData *)ph->data;
 459     struct TagItem *tag;
 460
 461     while ((tag = NextTagItem((struct TagItem **)&taglist)))
 462     {
 463         switch (tag->ti_Tag)
 464         {
 465         case PT_DOSENVEC:
 466             CopyMem((struct DosEnvec *)tag->ti_Data, &ph->de, sizeof(struct DosEnvec));
 467             PartitionMBRSetDosEnvec(ph->root, data->entry, (struct DosEnvec *)tag->ti_Data);
 468             break;
 469
 470         case PT_TYPE:
 471             data->entry->type = PTYPE(tag->ti_Data)->id[0];
 472             /* Update DOSType according to a new type ID */
 473             setDosType(&ph->de, MBR_FindDosType(data->entry->type));
 474             break;
 475
 476         case PT_POSITION:
 477             if (tag->ti_Data != data->position)
 478             {
 479             struct PartitionHandle *node;
 480             struct PCPartitionTable *entry;
 481
 482                 node = (struct PartitionHandle *)ph->root->table->list.lh_Head;
 483                 while (node->ln.ln_Succ)
 484                 {
 485                     if (tag->ti_Data == ((struct MBRData *)node->data)->position)
 486                         goto posbreak;
 487                     node = (struct PartitionHandle *)node->ln.ln_Succ;
 488                 }
 489                 data->position = tag->ti_Data;
 490                 entry = &((struct MBR *)ph->root->table->data)->pcpt[data->position];
 491                 CopyMem(data->entry, entry, sizeof(struct PCPartitionTable));
 492                 memset(data->entry, 0, sizeof(struct PCPartitionTable));
 493                 data->entry = entry;
 494                 ph->ln.ln_Pri = MBR_MAX_PARTITIONS-1-data->position;
 495                 Remove(&ph->ln);
 496                 Enqueue(&ph->root->table->list, &ph->ln);
 497 posbreak:
 498             ;
 499             }
 500             break;
 501
 502         case PT_ACTIVE:
 503             if (tag->ti_Data)
 504                 data->entry->status |= 0x80;
 505             else
 506                 data->entry->status &= ~0x80;
 507             break;
 508         }
 509     }
 510     return 0;
 511 }
 512
 513 static const struct PartitionAttribute PartitionMBRPartitionTableAttrs[]=
 514 {
 515     {PTT_TYPE,           PLAM_READ},
 516     {PTT_RESERVED,       PLAM_READ},
 517     {PTT_MAX_PARTITIONS, PLAM_READ},
 518     {TAG_DONE,           0}
 519 };
 520
 521 static const struct PartitionAttribute PartitionMBRPartitionAttrs[]=
 522 {
 523     {PT_GEOMETRY,  PLAM_READ},
 524     {PT_TYPE,      PLAM_READ | PLAM_WRITE},
 525     {PT_POSITION,  PLAM_READ | PLAM_WRITE},
 526     {PT_ACTIVE,    PLAM_READ | PLAM_WRITE},
 527     {PT_STARTBLOCK, PLAM_READ},
 528     {PT_ENDBLOCK,   PLAM_READ},
 529     {TAG_DONE, 0}
 530 };
 531
 532 ULONG PartitionMBRDestroyPartitionTable(struct Library *PartitionBase,
 533     struct PartitionHandle *root)
 534 {
 535     struct MBR *mbr = root->table->data;
 536
 537     memset(mbr->pcpt, 0, sizeof(mbr->pcpt));
 538     /* deleting the magic value will invalidate the
 539      * partition table so it cannot be opened again
 540      */
 541     mbr->magic = 0;
 542     if (writeBlock(PartitionBase, root, 0, root->table->data))
 543         return 1;
 544     return 0;
 545 }
 546
 547 const struct PTFunctionTable PartitionMBR =
 548 {
 549     PHPTT_MBR,
 550     "PC-MBR",
 551     PartitionMBRCheckPartitionTable,
 552     PartitionMBROpenPartitionTable,
 553     PartitionMBRClosePartitionTable,
 554     PartitionMBRWritePartitionTable,
 555     PartitionMBRCreatePartitionTable,
 556     PartitionMBRAddPartition,
 557     PartitionMBRDeletePartition,
 558     PartitionMBRGetPartitionTableAttr,
 559     NULL,
 560     PartitionMBRGetPartitionAttr,
 561     PartitionMBRSetPartitionAttrs,
 562     PartitionMBRPartitionTableAttrs,
 563     PartitionMBRPartitionAttrs,
 564     PartitionMBRDestroyPartitionTable,
 565     NULL
 566 };
 567