boot/freeldr/freeldr/disk/partition.c

   1 /*
   2  *  FreeLoader
   3  *  Copyright (C) 1998-2003  Brian Palmer  <brianp@sginet.com>
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License along
  16  *  with this program; if not, write to the Free Software Foundation, Inc.,
  17  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #ifndef _M_ARM
  21 #include <freeldr.h>
  22 #include <debug.h>
  23
  24 DBG_DEFAULT_CHANNEL(DISK);
  25
  26 BOOLEAN DiskGetActivePartitionEntry(UCHAR DriveNumber,
  27                                  PPARTITION_TABLE_ENTRY PartitionTableEntry,
  28                                  ULONG *ActivePartition)
  29 {
  30     ULONG              BootablePartitionCount = 0;
  31     MASTER_BOOT_RECORD MasterBootRecord;
  32
  33     *ActivePartition = 0;
  34
  35     // Read master boot record
  36     if (!DiskReadBootRecord(DriveNumber, 0, &MasterBootRecord))
  37     {
  38         return FALSE;
  39     }
  40
  41     // Count the bootable partitions
  42     if (MasterBootRecord.PartitionTable[0].BootIndicator == 0x80)
  43     {
  44         BootablePartitionCount++;
  45         *ActivePartition = 1;
  46     }
  47     if (MasterBootRecord.PartitionTable[1].BootIndicator == 0x80)
  48     {
  49         BootablePartitionCount++;
  50         *ActivePartition = 2;
  51     }
  52     if (MasterBootRecord.PartitionTable[2].BootIndicator == 0x80)
  53     {
  54         BootablePartitionCount++;
  55         *ActivePartition = 3;
  56     }
  57     if (MasterBootRecord.PartitionTable[3].BootIndicator == 0x80)
  58     {
  59         BootablePartitionCount++;
  60         *ActivePartition = 4;
  61     }
  62
  63     // Make sure there was only one bootable partition
  64     if (BootablePartitionCount == 0)
  65     {
  66         ERR("No bootable (active) partitions found.\n");
  67         return FALSE;
  68     }
  69     else if (BootablePartitionCount != 1)
  70     {
  71         ERR("Too many bootable (active) partitions found.\n");
  72         return FALSE;
  73     }
  74
  75     // Copy the partition table entry
  76     RtlCopyMemory(PartitionTableEntry,
  77                   &MasterBootRecord.PartitionTable[*ActivePartition - 1],
  78                   sizeof(PARTITION_TABLE_ENTRY));
  79
  80     return TRUE;
  81 }
  82
  83 BOOLEAN DiskGetPartitionEntry(UCHAR DriveNumber, ULONG PartitionNumber, PPARTITION_TABLE_ENTRY PartitionTableEntry)
  84 {
  85     MASTER_BOOT_RECORD        MasterBootRecord;
  86     PARTITION_TABLE_ENTRY    ExtendedPartitionTableEntry;
  87     ULONG                        ExtendedPartitionNumber;
  88     ULONG                        ExtendedPartitionOffset;
  89     ULONG                        Index;
  90
  91     // Read master boot record
  92     if (!DiskReadBootRecord(DriveNumber, 0, &MasterBootRecord))
  93     {
  94         return FALSE;
  95     }
  96
  97     // If they are asking for a primary
  98     // partition then things are easy
  99     if (PartitionNumber < 5)
 100     {
 101         // PartitionNumber is one-based and we need it zero-based
 102         PartitionNumber--;
 103
 104         // Copy the partition table entry
 105         RtlCopyMemory(PartitionTableEntry, &MasterBootRecord.PartitionTable[PartitionNumber], sizeof(PARTITION_TABLE_ENTRY));
 106
 107         return TRUE;
 108     }
 109     else
 110     {
 111         // They want an extended partition entry so we will need
 112         // to loop through all the extended partitions on the disk
 113         // and return the one they want.
 114
 115         ExtendedPartitionNumber = PartitionNumber - 5;
 116
 117         // Set the initial relative starting sector to 0
 118         // This is because extended partition starting
 119         // sectors a numbered relative to their parent
 120         ExtendedPartitionOffset = 0;
 121
 122         for (Index=0; Index<=ExtendedPartitionNumber; Index++)
 123         {
 124             // Get the extended partition table entry
 125             if (!DiskGetFirstExtendedPartitionEntry(&MasterBootRecord, &ExtendedPartitionTableEntry))
 126             {
 127                 return FALSE;
 128             }
 129
 130             // Adjust the relative starting sector of the partition
 131             ExtendedPartitionTableEntry.SectorCountBeforePartition += ExtendedPartitionOffset;
 132             if (ExtendedPartitionOffset == 0)
 133             {
 134                 // Set the start of the parrent extended partition
 135                 ExtendedPartitionOffset = ExtendedPartitionTableEntry.SectorCountBeforePartition;
 136             }
 137             // Read the partition boot record
 138             if (!DiskReadBootRecord(DriveNumber, ExtendedPartitionTableEntry.SectorCountBeforePartition, &MasterBootRecord))
 139             {
 140                 return FALSE;
 141             }
 142
 143             // Get the first real partition table entry
 144             if (!DiskGetFirstPartitionEntry(&MasterBootRecord, PartitionTableEntry))
 145             {
 146                 return FALSE;
 147             }
 148
 149             // Now correct the start sector of the partition
 150             PartitionTableEntry->SectorCountBeforePartition += ExtendedPartitionTableEntry.SectorCountBeforePartition;
 151         }
 152
 153         // When we get here we should have the correct entry
 154         // already stored in PartitionTableEntry
 155         // so just return TRUE
 156         return TRUE;
 157     }
 158
 159 }
 160
 161 BOOLEAN DiskGetFirstPartitionEntry(PMASTER_BOOT_RECORD MasterBootRecord, PPARTITION_TABLE_ENTRY PartitionTableEntry)
 162 {
 163     ULONG        Index;
 164
 165     for (Index=0; Index<4; Index++)
 166     {
 167         // Check the system indicator
 168         // If it's not an extended or unused partition
 169         // then we're done
 170         if ((MasterBootRecord->PartitionTable[Index].SystemIndicator != PARTITION_ENTRY_UNUSED) &&
 171             (MasterBootRecord->PartitionTable[Index].SystemIndicator != PARTITION_EXTENDED) &&
 172             (MasterBootRecord->PartitionTable[Index].SystemIndicator != PARTITION_XINT13_EXTENDED))
 173         {
 174             RtlCopyMemory(PartitionTableEntry, &MasterBootRecord->PartitionTable[Index], sizeof(PARTITION_TABLE_ENTRY));
 175             return TRUE;
 176         }
 177     }
 178
 179     return FALSE;
 180 }
 181
 182 BOOLEAN DiskGetFirstExtendedPartitionEntry(PMASTER_BOOT_RECORD MasterBootRecord, PPARTITION_TABLE_ENTRY PartitionTableEntry)
 183 {
 184     ULONG        Index;
 185
 186     for (Index=0; Index<4; Index++)
 187     {
 188         // Check the system indicator
 189         // If it an extended partition then we're done
 190         if ((MasterBootRecord->PartitionTable[Index].SystemIndicator == PARTITION_EXTENDED) ||
 191             (MasterBootRecord->PartitionTable[Index].SystemIndicator == PARTITION_XINT13_EXTENDED))
 192         {
 193             RtlCopyMemory(PartitionTableEntry, &MasterBootRecord->PartitionTable[Index], sizeof(PARTITION_TABLE_ENTRY));
 194             return TRUE;
 195         }
 196     }
 197
 198     return FALSE;
 199 }
 200
 201 BOOLEAN DiskReadBootRecord(UCHAR DriveNumber, ULONGLONG LogicalSectorNumber, PMASTER_BOOT_RECORD BootRecord)
 202 {
 203     ULONG Index;
 204
 205     // Read master boot record
 206     if (!MachDiskReadLogicalSectors(DriveNumber, LogicalSectorNumber, 1, DiskReadBuffer))
 207     {
 208         return FALSE;
 209     }
 210     RtlCopyMemory(BootRecord, DiskReadBuffer, sizeof(MASTER_BOOT_RECORD));
 211
 212     TRACE("Dumping partition table for drive 0x%x:\n", DriveNumber);
 213     TRACE("Boot record logical start sector = %d\n", LogicalSectorNumber);
 214     TRACE("sizeof(MASTER_BOOT_RECORD) = 0x%x.\n", sizeof(MASTER_BOOT_RECORD));
 215
 216     for (Index=0; Index<4; Index++)
 217     {
 218         TRACE("-------------------------------------------\n");
 219         TRACE("Partition %d\n", (Index + 1));
 220         TRACE("BootIndicator: 0x%x\n", BootRecord->PartitionTable[Index].BootIndicator);
 221         TRACE("StartHead: 0x%x\n", BootRecord->PartitionTable[Index].StartHead);
 222         TRACE("StartSector (Plus 2 cylinder bits): 0x%x\n", BootRecord->PartitionTable[Index].StartSector);
 223         TRACE("StartCylinder: 0x%x\n", BootRecord->PartitionTable[Index].StartCylinder);
 224         TRACE("SystemIndicator: 0x%x\n", BootRecord->PartitionTable[Index].SystemIndicator);
 225         TRACE("EndHead: 0x%x\n", BootRecord->PartitionTable[Index].EndHead);
 226         TRACE("EndSector (Plus 2 cylinder bits): 0x%x\n", BootRecord->PartitionTable[Index].EndSector);
 227         TRACE("EndCylinder: 0x%x\n", BootRecord->PartitionTable[Index].EndCylinder);
 228         TRACE("SectorCountBeforePartition: 0x%x\n", BootRecord->PartitionTable[Index].SectorCountBeforePartition);
 229         TRACE("PartitionSectorCount: 0x%x\n", BootRecord->PartitionTable[Index].PartitionSectorCount);
 230     }
 231
 232     // Check the partition table magic value
 233     if (BootRecord->MasterBootRecordMagic != 0xaa55)
 234     {
 235         return FALSE;
 236     }
 237
 238     return TRUE;
 239 }
 240
 241 NTSTATUS
 242 NTAPI
 243 IopReadBootRecord(
 244     IN PDEVICE_OBJECT DeviceObject,
 245     IN ULONGLONG LogicalSectorNumber,
 246     IN ULONG SectorSize,
 247     OUT PMASTER_BOOT_RECORD BootRecord)
 248 {
 249     ULONG FileId = (ULONG)DeviceObject;
 250     LARGE_INTEGER Position;
 251     ULONG BytesRead;
 252     ARC_STATUS Status;
 253
 254     Position.QuadPart = LogicalSectorNumber * SectorSize;
 255     Status = ArcSeek(FileId, &Position, SeekAbsolute);
 256     if (Status != ESUCCESS)
 257         return STATUS_IO_DEVICE_ERROR;
 258
 259     Status = ArcRead(FileId, BootRecord, SectorSize, &BytesRead);
 260     if (Status != ESUCCESS || BytesRead != SectorSize)
 261         return STATUS_IO_DEVICE_ERROR;
 262
 263     return STATUS_SUCCESS;
 264 }
 265
 266 BOOLEAN
 267 NTAPI
 268 IopCopyPartitionRecord(
 269     IN BOOLEAN ReturnRecognizedPartitions,
 270     IN ULONG SectorSize,
 271     IN PPARTITION_TABLE_ENTRY PartitionTableEntry,
 272     OUT PARTITION_INFORMATION *PartitionEntry)
 273 {
 274     BOOLEAN IsRecognized;
 275
 276     IsRecognized = TRUE; /* FIXME */
 277     if (!IsRecognized && ReturnRecognizedPartitions)
 278         return FALSE;
 279
 280     PartitionEntry->StartingOffset.QuadPart = (ULONGLONG)PartitionTableEntry->SectorCountBeforePartition * SectorSize;
 281     PartitionEntry->PartitionLength.QuadPart = (ULONGLONG)PartitionTableEntry->PartitionSectorCount * SectorSize;
 282     PartitionEntry->HiddenSectors = 0;
 283     PartitionEntry->PartitionNumber = 0; /* Will be filled later */
 284     PartitionEntry->PartitionType = PartitionTableEntry->SystemIndicator;
 285     PartitionEntry->BootIndicator = (PartitionTableEntry->BootIndicator & 0x80) ? TRUE : FALSE;
 286     PartitionEntry->RecognizedPartition = IsRecognized;
 287     PartitionEntry->RewritePartition = FALSE;
 288
 289     return TRUE;
 290 }
 291
 292 NTSTATUS
 293 FASTCALL
 294 IoReadPartitionTable(
 295     IN PDEVICE_OBJECT DeviceObject,
 296     IN ULONG SectorSize,
 297     IN BOOLEAN ReturnRecognizedPartitions,
 298     OUT PDRIVE_LAYOUT_INFORMATION *PartitionBuffer)
 299 {
 300     PMASTER_BOOT_RECORD MasterBootRecord;
 301     PDRIVE_LAYOUT_INFORMATION Partitions;
 302     ULONG NbPartitions, i, Size;
 303     NTSTATUS ret;
 304
 305     *PartitionBuffer = NULL;
 306
 307     if (SectorSize < sizeof(MASTER_BOOT_RECORD))
 308         return STATUS_NOT_SUPPORTED;
 309
 310     MasterBootRecord = ExAllocatePool(NonPagedPool, SectorSize);
 311     if (!MasterBootRecord)
 312         return STATUS_NO_MEMORY;
 313
 314     /* Read disk MBR */
 315     ret = IopReadBootRecord(DeviceObject, 0, SectorSize, MasterBootRecord);
 316     if (!NT_SUCCESS(ret))
 317     {
 318         ExFreePool(MasterBootRecord);
 319         return ret;
 320     }
 321
 322     /* Check validity of boot record */
 323     if (MasterBootRecord->MasterBootRecordMagic != 0xaa55)
 324     {
 325         ExFreePool(MasterBootRecord);
 326         return STATUS_NOT_SUPPORTED;
 327     }
 328
 329     /* Count number of partitions */
 330     NbPartitions = 0;
 331     for (i = 0; i < 4; i++)
 332     {
 333         NbPartitions++;
 334
 335         if (MasterBootRecord->PartitionTable[i].SystemIndicator == PARTITION_EXTENDED ||
 336             MasterBootRecord->PartitionTable[i].SystemIndicator == PARTITION_XINT13_EXTENDED)
 337         {
 338             /* FIXME: unhandled case; count number of partitions */
 339             UNIMPLEMENTED;
 340         }
 341     }
 342
 343     if (NbPartitions == 0)
 344     {
 345         ExFreePool(MasterBootRecord);
 346         return STATUS_NOT_SUPPORTED;
 347     }
 348
 349     /* Allocation space to store partitions */
 350     Size = FIELD_OFFSET(DRIVE_LAYOUT_INFORMATION, PartitionEntry) +
 351            NbPartitions * sizeof(PARTITION_INFORMATION);
 352     Partitions = ExAllocatePool(NonPagedPool, Size);
 353     if (!Partitions)
 354     {
 355         ExFreePool(MasterBootRecord);
 356         return STATUS_NO_MEMORY;
 357     }
 358
 359     /* Count number of partitions */
 360     NbPartitions = 0;
 361     for (i = 0; i < 4; i++)
 362     {
 363         if (IopCopyPartitionRecord(ReturnRecognizedPartitions,
 364                                    SectorSize,
 365                                    &MasterBootRecord->PartitionTable[i],
 366                                    &Partitions->PartitionEntry[NbPartitions]))
 367         {
 368             Partitions->PartitionEntry[NbPartitions].PartitionNumber = NbPartitions + 1;
 369             NbPartitions++;
 370         }
 371
 372         if (MasterBootRecord->PartitionTable[i].SystemIndicator == PARTITION_EXTENDED ||
 373             MasterBootRecord->PartitionTable[i].SystemIndicator == PARTITION_XINT13_EXTENDED)
 374         {
 375             /* FIXME: unhandled case; copy partitions */
 376             UNIMPLEMENTED;
 377         }
 378     }
 379
 380     Partitions->PartitionCount = NbPartitions;
 381     Partitions->Signature = MasterBootRecord->Signature;
 382     ExFreePool(MasterBootRecord);
 383
 384     *PartitionBuffer = Partitions;
 385     return STATUS_SUCCESS;
 386 }
 387
 388 #endif