📄 fat32.c
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/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS VFAT filesystem library
* FILE: fat32.c
* PURPOSE: Fat32 support
* PROGRAMMERS: Casper S. Hornstrup (chorns@users.sourceforge.net)
* Eric Kohl (ekohl@rz-online.de)
* REVISIONS:
* EK 05/04-2003 Created
*/
#include "vfatlib.h"
#define NDEBUG
#include <debug.h>
static ULONG
GetShiftCount(ULONG Value)
{
ULONG i = 1;
while (Value > 0)
{
i++;
Value /= 2;
}
return i - 2;
}
static ULONG
CalcVolumeSerialNumber(VOID)
{
LARGE_INTEGER SystemTime;
TIME_FIELDS TimeFields;
ULONG Serial;
PUCHAR Buffer;
NtQuerySystemTime (&SystemTime);
RtlTimeToTimeFields (&SystemTime, &TimeFields);
Buffer = (PUCHAR)&Serial;
Buffer[0] = (UCHAR)(TimeFields.Year & 0xFF) + (UCHAR)(TimeFields.Hour & 0xFF);
Buffer[1] = (UCHAR)(TimeFields.Year >> 8) + (UCHAR)(TimeFields.Minute & 0xFF);
Buffer[2] = (UCHAR)(TimeFields.Month & 0xFF) + (UCHAR)(TimeFields.Second & 0xFF);
Buffer[3] = (UCHAR)(TimeFields.Day & 0xFF) + (UCHAR)(TimeFields.Milliseconds & 0xFF);
return Serial;
}
static NTSTATUS
Fat32WriteBootSector (IN HANDLE FileHandle,
IN PFAT32_BOOT_SECTOR BootSector,
IN OUT PFORMAT_CONTEXT Context)
{
IO_STATUS_BLOCK IoStatusBlock;
NTSTATUS Status;
PUCHAR NewBootSector;
LARGE_INTEGER FileOffset;
/* Allocate buffer for new bootsector */
NewBootSector = (PUCHAR)RtlAllocateHeap(RtlGetProcessHeap(),
0,
SECTORSIZE);
if (NewBootSector == NULL)
return(STATUS_INSUFFICIENT_RESOURCES);
/* Zero the new bootsector */
memset(NewBootSector, 0, SECTORSIZE);
/* Copy FAT32 BPB to new bootsector */
memcpy((NewBootSector + 3),
&BootSector->OEMName[0],
87); /* FAT32 BPB length (up to (not including) Res2) */
/* Write sector 0 */
FileOffset.QuadPart = 0ULL;
Status = NtWriteFile(FileHandle,
NULL,
NULL,
NULL,
&IoStatusBlock,
NewBootSector,
SECTORSIZE,
&FileOffset,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT("NtWriteFile() failed (Status %lx)\n", Status);
RtlFreeHeap(RtlGetProcessHeap(), 0, NewBootSector);
return Status;
}
UpdateProgress (Context, 1);
/* Write backup boot sector */
if (BootSector->BootBackup != 0x0000)
{
FileOffset.QuadPart = (ULONGLONG)((ULONG) BootSector->BootBackup * SECTORSIZE);
Status = NtWriteFile(FileHandle,
NULL,
NULL,
NULL,
&IoStatusBlock,
NewBootSector,
SECTORSIZE,
&FileOffset,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT("NtWriteFile() failed (Status %lx)\n", Status);
RtlFreeHeap(RtlGetProcessHeap(), 0, NewBootSector);
return Status;
}
UpdateProgress (Context, 1);
}
/* Free the new boot sector */
RtlFreeHeap(RtlGetProcessHeap(), 0, NewBootSector);
return Status;
}
static NTSTATUS
Fat32WriteFsInfo (IN HANDLE FileHandle,
IN PFAT32_BOOT_SECTOR BootSector,
IN OUT PFORMAT_CONTEXT Context)
{
IO_STATUS_BLOCK IoStatusBlock;
NTSTATUS Status;
PFAT32_FSINFO FsInfo;
LARGE_INTEGER FileOffset;
/* Allocate buffer for new sector */
FsInfo = (PFAT32_FSINFO)RtlAllocateHeap(RtlGetProcessHeap(),
0,
BootSector->BytesPerSector);
if (FsInfo == NULL)
return(STATUS_INSUFFICIENT_RESOURCES);
/* Zero the new sector */
memset(FsInfo, 0, BootSector->BytesPerSector);
FsInfo->LeadSig = 0x41615252;
FsInfo->StrucSig = 0x61417272;
FsInfo->FreeCount = 0xffffffff;
FsInfo->NextFree = 0xffffffff;
FsInfo->TrailSig = 0xaa550000;
/* Write sector */
FileOffset.QuadPart = BootSector->FSInfoSector * BootSector->BytesPerSector;
Status = NtWriteFile(FileHandle,
NULL,
NULL,
NULL,
&IoStatusBlock,
FsInfo,
BootSector->BytesPerSector,
&FileOffset,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT("NtWriteFile() failed (Status %lx)\n", Status);
RtlFreeHeap(RtlGetProcessHeap(), 0, FsInfo);
return(Status);
}
UpdateProgress (Context, 1);
/* Free the new sector buffer */
RtlFreeHeap(RtlGetProcessHeap(), 0, FsInfo);
return(Status);
}
static NTSTATUS
Fat32WriteFAT (IN HANDLE FileHandle,
IN ULONG SectorOffset,
IN PFAT32_BOOT_SECTOR BootSector,
IN OUT PFORMAT_CONTEXT Context)
{
IO_STATUS_BLOCK IoStatusBlock;
NTSTATUS Status;
PUCHAR Buffer;
LARGE_INTEGER FileOffset;
ULONG i;
ULONG Sectors;
/* Allocate buffer */
Buffer = (PUCHAR)RtlAllocateHeap(RtlGetProcessHeap(),
0,
64 * 1024);
if (Buffer == NULL)
return(STATUS_INSUFFICIENT_RESOURCES);
/* Zero the buffer */
memset(Buffer, 0, 64 * 1024);
/* FAT cluster 0 */
Buffer[0] = 0xf8; /* Media type */
Buffer[1] = 0xff;
Buffer[2] = 0xff;
Buffer[3] = 0x0f;
/* FAT cluster 1 */
Buffer[4] = 0xff; /* Clean shutdown, no disk read/write errors, end-of-cluster (EOC) mark */
Buffer[5] = 0xff;
Buffer[6] = 0xff;
Buffer[7] = 0x0f;
/* FAT cluster 2 */
Buffer[8] = 0xff; /* End of root directory */
Buffer[9] = 0xff;
Buffer[10] = 0xff;
Buffer[11] = 0x0f;
/* Write first sector of the FAT */
FileOffset.QuadPart = (SectorOffset + BootSector->ReservedSectors) * BootSector->BytesPerSector;
Status = NtWriteFile(FileHandle,
NULL,
NULL,
NULL,
&IoStatusBlock,
Buffer,
BootSector->BytesPerSector,
&FileOffset,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT("NtWriteFile() failed (Status %lx)\n", Status);
RtlFreeHeap(RtlGetProcessHeap(), 0, Buffer);
return(Status);
}
UpdateProgress (Context, 1);
/* Zero the begin of the buffer */
memset(Buffer, 0, 12);
/* Zero the rest of the FAT */
Sectors = 64 * 1024 / BootSector->BytesPerSector;
for (i = 1; i < BootSector->FATSectors32; i += Sectors)
{
/* Zero some sectors of the FAT */
FileOffset.QuadPart = (SectorOffset + BootSector->ReservedSectors + i) * BootSector->BytesPerSector;
if ((BootSector->FATSectors32 - i) <= Sectors)
{
Sectors = BootSector->FATSectors32 - i;
}
Status = NtWriteFile(FileHandle,
NULL,
NULL,
NULL,
&IoStatusBlock,
Buffer,
Sectors * BootSector->BytesPerSector,
&FileOffset,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT("NtWriteFile() failed (Status %lx)\n", Status);
RtlFreeHeap(RtlGetProcessHeap(), 0, Buffer);
return(Status);
}
UpdateProgress (Context, Sectors);
}
/* Free the buffer */
RtlFreeHeap(RtlGetProcessHeap(), 0, Buffer);
return(Status);
}
static NTSTATUS
Fat32WriteRootDirectory (IN HANDLE FileHandle,
IN PFAT32_BOOT_SECTOR BootSector,
IN OUT PFORMAT_CONTEXT Context)
{
IO_STATUS_BLOCK IoStatusBlock;
NTSTATUS Status;
PUCHAR Buffer;
LARGE_INTEGER FileOffset;
ULONGLONG FirstDataSector;
ULONGLONG FirstRootDirSector;
/* Allocate buffer for the cluster */
Buffer = (PUCHAR)RtlAllocateHeap(RtlGetProcessHeap(),
0,
BootSector->SectorsPerCluster * BootSector->BytesPerSector);
if (Buffer == NULL)
return(STATUS_INSUFFICIENT_RESOURCES);
/* Zero the buffer */
memset(Buffer, 0, BootSector->SectorsPerCluster * BootSector->BytesPerSector);
DPRINT("BootSector->ReservedSectors = %lu\n", BootSector->ReservedSectors);
DPRINT("BootSector->FATSectors32 = %lu\n", BootSector->FATSectors32);
DPRINT("BootSector->RootCluster = %lu\n", BootSector->RootCluster);
DPRINT("BootSector->SectorsPerCluster = %lu\n", BootSector->SectorsPerCluster);
/* Write cluster */
FirstDataSector = BootSector->ReservedSectors +
(BootSector->FATCount * BootSector->FATSectors32) + 0 /* RootDirSectors */;
DPRINT("FirstDataSector = %lu\n", FirstDataSector);
FirstRootDirSector = ((BootSector->RootCluster - 2) * BootSector->SectorsPerCluster) + FirstDataSector;
FileOffset.QuadPart = FirstRootDirSector * BootSector->BytesPerSector;
DPRINT("FirstRootDirSector = %lu\n", FirstRootDirSector);
DPRINT("FileOffset = %lu\n", FileOffset.QuadPart);
Status = NtWriteFile(FileHandle,
NULL,
NULL,
NULL,
&IoStatusBlock,
Buffer,
BootSector->SectorsPerCluster * BootSector->BytesPerSector,
&FileOffset,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT("NtWriteFile() failed (Status %lx)\n", Status);
RtlFreeHeap(RtlGetProcessHeap(), 0, Buffer);
return(Status);
}
UpdateProgress (Context, (ULONG)BootSector->SectorsPerCluster);
/* Free the buffer */
RtlFreeHeap(RtlGetProcessHeap(), 0, Buffer);
return(Status);
}
NTSTATUS
Fat32Format (HANDLE FileHandle,
PPARTITION_INFORMATION PartitionInfo,
PDISK_GEOMETRY DiskGeometry,
PUNICODE_STRING Label,
BOOLEAN QuickFormat,
ULONG ClusterSize,
PFORMAT_CONTEXT Context)
{
FAT32_BOOT_SECTOR BootSector;
OEM_STRING VolumeLabel;
ULONG RootDirSectors;
ULONG TmpVal1;
ULONG TmpVal2;
NTSTATUS Status;
/* Calculate cluster size */
if (ClusterSize == 0)
{
if (PartitionInfo->PartitionLength.QuadPart < 8LL * 1024LL * 1024LL * 1024LL)
{
/* Partition < 8GB ==> 4KB Cluster */
ClusterSize = 4096;
}
else if (PartitionInfo->PartitionLength.QuadPart < 16LL * 1024LL * 1024LL * 1024LL)
{
/* Partition 8GB - 16GB ==> 8KB Cluster */
ClusterSize = 8192;
}
else if (PartitionInfo->PartitionLength.QuadPart < 32LL * 1024LL * 1024LL * 1024LL)
{
/* Partition 16GB - 32GB ==> 16KB Cluster */
ClusterSize = 16384;
}
else
{
/* Partition >= 32GB ==> 32KB Cluster */
ClusterSize = 32768;
}
}
memset(&BootSector, 0, sizeof(FAT32_BOOT_SECTOR));
memcpy(&BootSector.OEMName[0], "MSWIN4.1", 8);
BootSector.BytesPerSector = DiskGeometry->BytesPerSector;
BootSector.SectorsPerCluster = ClusterSize / BootSector.BytesPerSector;
BootSector.ReservedSectors = 32;
BootSector.FATCount = 2;
BootSector.RootEntries = 0;
BootSector.Sectors = 0;
BootSector.Media = 0xf8;
BootSector.FATSectors = 0;
BootSector.SectorsPerTrack = DiskGeometry->SectorsPerTrack;
BootSector.Heads = DiskGeometry->TracksPerCylinder;
BootSector.HiddenSectors = PartitionInfo->HiddenSectors;
BootSector.SectorsHuge = PartitionInfo->PartitionLength.QuadPart >>
GetShiftCount(BootSector.BytesPerSector); /* Use shifting to avoid 64-bit division */
BootSector.FATSectors32 = 0; /* Set later */
BootSector.ExtFlag = 0; /* Mirror all FATs */
BootSector.FSVersion = 0x0000; /* 0:0 */
BootSector.RootCluster = 2;
BootSector.FSInfoSector = 1;
BootSector.BootBackup = 6;
BootSector.Drive = 0xff; /* No BIOS boot drive available */
BootSector.ExtBootSignature = 0x29;
BootSector.VolumeID = CalcVolumeSerialNumber ();
if ((Label == NULL) || (Label->Buffer == NULL))
{
memcpy(&BootSector.VolumeLabel[0], "NO NAME ", 11);
}
else
{
RtlUnicodeStringToOemString(&VolumeLabel, Label, TRUE);
memset(&BootSector.VolumeLabel[0], ' ', 11);
memcpy(&BootSector.VolumeLabel[0], VolumeLabel.Buffer,
VolumeLabel.Length < 11 ? VolumeLabel.Length : 11);
RtlFreeOemString(&VolumeLabel);
}
memcpy(&BootSector.SysType[0], "FAT32 ", 8);
RootDirSectors = ((BootSector.RootEntries * 32) +
(BootSector.BytesPerSector - 1)) / BootSector.BytesPerSector;
/* Calculate number of FAT sectors */
/* (BytesPerSector / 4) FAT entries (32bit) fit into one sector */
TmpVal1 = BootSector.SectorsHuge - BootSector.ReservedSectors;
TmpVal2 = ((BootSector.BytesPerSector / 4) * BootSector.SectorsPerCluster) + BootSector.FATCount;
BootSector.FATSectors32 = (TmpVal1 + (TmpVal2 - 1)) / TmpVal2;
DPRINT("FATSectors32 = %lu\n", BootSector.FATSectors32);
/* Init context data */
Context->TotalSectorCount =
2 + (BootSector.FATSectors32 * BootSector.FATCount) + BootSector.SectorsPerCluster;
Status = Fat32WriteBootSector (FileHandle,
&BootSector,
Context);
if (!NT_SUCCESS(Status))
{
DPRINT("Fat32WriteBootSector() failed with status 0x%.08x\n", Status);
return Status;
}
Status = Fat32WriteFsInfo (FileHandle,
&BootSector,
Context);
if (!NT_SUCCESS(Status))
{
DPRINT("Fat32WriteFsInfo() failed with status 0x%.08x\n", Status);
return Status;
}
/* Write first FAT copy */
Status = Fat32WriteFAT (FileHandle,
0,
&BootSector,
Context);
if (!NT_SUCCESS(Status))
{
DPRINT("Fat32WriteFAT() failed with status 0x%.08x\n", Status);
return Status;
}
/* Write second FAT copy */
Status = Fat32WriteFAT (FileHandle,
BootSector.FATSectors32,
&BootSector,
Context);
if (!NT_SUCCESS(Status))
{
DPRINT("Fat32WriteFAT() failed with status 0x%.08x.\n", Status);
return Status;
}
Status = Fat32WriteRootDirectory (FileHandle,
&BootSector,
Context);
if (!NT_SUCCESS(Status))
{
DPRINT("Fat32WriteRootDirectory() failed with status 0x%.08x\n", Status);
}
if (!QuickFormat)
{
/* FIXME: Fill remaining sectors */
}
return Status;
}
/* EOF */
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