fat.c File Reference

#include <bl.h>
#include <fs_rec/fs_rec.h>

Include dependency graph for fat.c:

Go to the source code of this file.

Functions
NTSTATUS	FatMount (_In_ ULONG DeviceId, _In_ ULONG Unknown, _Out_ PBL_FILE_ENTRY *FileEntry)
NTSTATUS	FatInitialize (VOID)

Variables
PVOID *	FatDeviceTable
ULONG	FatDeviceTableEntries
PWCHAR	FatpLongFileName

Function Documentation

FatInitialize()

NTSTATUS FatInitialize

(

VOID

)

Definition at line 81 of file fat.c.

{
    NTSTATUS Status;
 
    /* Allocate the device table with 2 entries*/
    FatDeviceTableEntries = 2;
    FatDeviceTable = BlMmAllocateHeap(sizeof(PBL_FILE_ENTRY) *
                                      FatDeviceTableEntries);
    if (FatDeviceTable)
    {
        /* Zero it out */
        RtlZeroMemory(FatDeviceTable,
                      sizeof(PBL_FILE_ENTRY) * FatDeviceTableEntries);
 
        /* Allocate a 512 byte buffer for long file name conversion */
        FatpLongFileName = BlMmAllocateHeap(512);
        Status = FatpLongFileName != NULL ? STATUS_SUCCESS : STATUS_NO_MEMORY;
    }
    else
    {
        /* No memory, fail */
        Status = STATUS_NO_MEMORY;
    }
 
    /* Return back to caller */
    return Status;
}

FatMount()

NTSTATUS FatMount	(	_In_ ULONG	DeviceId,
		_In_ ULONG	Unknown,
		_Out_ PBL_FILE_ENTRY *	FileEntry
	)

Definition at line 23 of file fat.c.

{
    BL_DEVICE_INFORMATION DeviceInformation;
    ULONG UnknownFlag;
    NTSTATUS Status;
    PACKED_BOOT_SECTOR FatBootSector;
    BIOS_PARAMETER_BLOCK BiosBlock;
 
    /* Capture thing */
    BlDeviceGetInformation(DeviceId, &DeviceInformation);
    UnknownFlag = DeviceInformation.BlockDeviceInfo.Unknown;
 
    /* Set thing to 1 */
    DeviceInformation.BlockDeviceInfo.Unknown |= 1;
    BlDeviceSetInformation(DeviceId, &DeviceInformation);
 
    /* Read the boot sector */
    Status = BlDeviceReadAtOffset(DeviceId,
                                  sizeof(FatBootSector),
                                  0,
                                  &FatBootSector,
                                  NULL);
 
    /* Restore thing back */
    DeviceInformation.BlockDeviceInfo.Unknown = UnknownFlag;
    BlDeviceSetInformation(DeviceId, &DeviceInformation);
    if (!NT_SUCCESS(Status))
    {
        EfiPrintf(L"Failed reading drive: %lx\r\n", Status);
        return Status;
    }
 
    FatUnpackBios(&BiosBlock, &FatBootSector.PackedBpb);
 
    /* For now, quickly fail if this isn't FAT */
    if (FatBootSector.Jump[0] != 0xE9)
    {
        return STATUS_UNSUCCESSFUL;
    }
 
    EfiPrintf(L"Jump: %lx Bytes Per Sector: %d Sectors Per Cluster: %d Reserved: %d Fats: %d Sectors: %d Large Sectors: %d Media: %lx RootEntries: %d\r\n",
              FatBootSector.Jump[0],
              BiosBlock.BytesPerSector,
              BiosBlock.SectorsPerCluster,
              BiosBlock.ReservedSectors,
              BiosBlock.Fats,
              BiosBlock.Sectors,
              BiosBlock.LargeSectors,
              BiosBlock.Media,
              BiosBlock.RootEntries);
    return STATUS_NOT_IMPLEMENTED;
}

Variable Documentation

FatDeviceTable

PVOID* FatDeviceTable

Definition at line 16 of file fat.c.

Referenced by FatInitialize().

FatDeviceTableEntries

ULONG FatDeviceTableEntries

Definition at line 17 of file fat.c.

Referenced by FatInitialize().

FatpLongFileName

PWCHAR FatpLongFileName

Definition at line 18 of file fat.c.

Referenced by FatInitialize().