/**
This function finds Eltorito partitions. Main algorithm
is ported from DXE partition driver.
@param PrivateData The global memory map
@param ParentBlockDevNo The parent block device
@retval TRUE New partitions are detected and logical block devices
are added to block device array
@retval FALSE No New partitions are added;
**/
BOOLEAN
FatFindEltoritoPartitions (
IN PEI_FAT_PRIVATE_DATA *PrivateData,
IN UINTN ParentBlockDevNo
)
{
EFI_STATUS Status;
BOOLEAN Found;
PEI_FAT_BLOCK_DEVICE *BlockDev;
PEI_FAT_BLOCK_DEVICE *ParentBlockDev;
UINT32 VolDescriptorLba;
UINT32 Lba;
CDROM_VOLUME_DESCRIPTOR *VolDescriptor;
ELTORITO_CATALOG *Catalog;
UINTN Check;
UINTN Index;
UINTN MaxIndex;
UINT16 *CheckBuffer;
UINT32 SubBlockSize;
UINT32 SectorCount;
UINT32 VolSpaceSize;
if (ParentBlockDevNo > PEI_FAT_MAX_BLOCK_DEVICE - 1) {
return FALSE;
}
Found = FALSE;
ParentBlockDev = &(PrivateData->BlockDevice[ParentBlockDevNo]);
VolSpaceSize = 0;
//
// CD_ROM has the fixed block size as 2048 bytes
//
if (ParentBlockDev->BlockSize != 2048) {
return FALSE;
}
VolDescriptor = (CDROM_VOLUME_DESCRIPTOR *) PrivateData->BlockData;
Catalog = (ELTORITO_CATALOG *) VolDescriptor;
//
// the ISO-9660 volume descriptor starts at 32k on the media
// and CD_ROM has the fixed block size as 2048 bytes, so...
//
VolDescriptorLba = 15;
//
// ((16*2048) / Media->BlockSize) - 1;
//
// Loop: handle one volume descriptor per time
//
while (TRUE) {
VolDescriptorLba += 1;
if (VolDescriptorLba > ParentBlockDev->LastBlock) {
//
// We are pointing past the end of the device so exit
//
break;
}
Status = FatReadBlock (
PrivateData,
ParentBlockDevNo,
VolDescriptorLba,
ParentBlockDev->BlockSize,
VolDescriptor
);
if (EFI_ERROR (Status)) {
break;
}
//
// Check for valid volume descriptor signature
//
if (VolDescriptor->Unknown.Type == CDVOL_TYPE_END ||
CompareMem (VolDescriptor->Unknown.Id, CDVOL_ID, sizeof (VolDescriptor->Unknown.Id)) != 0
) {
//
// end of Volume descriptor list
//
break;
}
//
// Read the Volume Space Size from Primary Volume Descriptor 81-88 byte
//
if (VolDescriptor->Unknown.Type == CDVOL_TYPE_CODED) {
VolSpaceSize = VolDescriptor->PrimaryVolume.VolSpaceSize[1];
}
//
// Is it an El Torito volume descriptor?
//
if (CompareMem (
VolDescriptor->BootRecordVolume.SystemId,
CDVOL_ELTORITO_ID,
sizeof (CDVOL_ELTORITO_ID) - 1
) != 0) {
continue;
}
//
// Read in the boot El Torito boot catalog
//
Lba = UNPACK_INT32 (VolDescriptor->BootRecordVolume.EltCatalog);
if (Lba > ParentBlockDev->LastBlock) {
continue;
}
Status = FatReadBlock (
PrivateData,
ParentBlockDevNo,
Lba,
ParentBlockDev->BlockSize,
Catalog
);
if (EFI_ERROR (Status)) {
continue;
}
//
// We don't care too much about the Catalog header's contents, but we do want
// to make sure it looks like a Catalog header
//
if (Catalog->Catalog.Indicator != ELTORITO_ID_CATALOG || Catalog->Catalog.Id55AA != 0xAA55) {
continue;
}
Check = 0;
CheckBuffer = (UINT16 *) Catalog;
for (Index = 0; Index < sizeof (ELTORITO_CATALOG) / sizeof (UINT16); Index += 1) {
Check += CheckBuffer[Index];
}
if ((Check & 0xFFFF) != 0) {
continue;
}
MaxIndex = ParentBlockDev->BlockSize / sizeof (ELTORITO_CATALOG);
for (Index = 1; Index < MaxIndex; Index += 1) {
//
// Next entry
//
Catalog += 1;
//
// Check this entry
//
if (Catalog->Boot.Indicator != ELTORITO_ID_SECTION_BOOTABLE || Catalog->Boot.Lba == 0) {
continue;
}
SubBlockSize = 512;
SectorCount = Catalog->Boot.SectorCount;
switch (Catalog->Boot.MediaType) {
case ELTORITO_NO_EMULATION:
SubBlockSize = ParentBlockDev->BlockSize;
SectorCount = Catalog->Boot.SectorCount;
break;
case ELTORITO_HARD_DISK:
break;
case ELTORITO_12_DISKETTE:
SectorCount = 0x50 * 0x02 * 0x0F;
break;
case ELTORITO_14_DISKETTE:
SectorCount = 0x50 * 0x02 * 0x12;
break;
case ELTORITO_28_DISKETTE:
SectorCount = 0x50 * 0x02 * 0x24;
break;
default:
SectorCount = 0;
SubBlockSize = ParentBlockDev->BlockSize;
break;
}
if (SectorCount < 2) {
SectorCount = (VolSpaceSize > ParentBlockDev->LastBlock + 1) ? (UINT32) (ParentBlockDev->LastBlock - Catalog->Boot.Lba + 1) : (UINT32) (VolSpaceSize - Catalog->Boot.Lba);
}
//
// Register this partition
//
if (PrivateData->BlockDeviceCount < PEI_FAT_MAX_BLOCK_DEVICE) {
Found = TRUE;
BlockDev = &(PrivateData->BlockDevice[PrivateData->BlockDeviceCount]);
BlockDev->BlockSize = SubBlockSize;
BlockDev->LastBlock = SectorCount - 1;
BlockDev->IoAlign = ParentBlockDev->IoAlign;
BlockDev->Logical = TRUE;
BlockDev->PartitionChecked = FALSE;
BlockDev->StartingPos = MultU64x32 (Catalog->Boot.Lba, ParentBlockDev->BlockSize);
BlockDev->ParentDevNo = ParentBlockDevNo;
PrivateData->BlockDeviceCount++;
}
}
}
ParentBlockDev->PartitionChecked = TRUE;
return Found;
}
/**
Disk reading.
@param PrivateData the global memory map;
@param BlockDeviceNo the block device to read;
@param StartingAddress the starting address.
@param Size the amount of data to read.
@param Buffer the buffer holding the data
@retval EFI_SUCCESS The function completed successfully.
@retval EFI_DEVICE_ERROR Something error.
**/
EFI_STATUS
FatReadDisk (
IN PEI_FAT_PRIVATE_DATA *PrivateData,
IN UINTN BlockDeviceNo,
IN UINT64 StartingAddress,
IN UINTN Size,
OUT VOID *Buffer
)
{
EFI_STATUS Status;
UINT32 BlockSize;
CHAR8 *BufferPtr;
CHAR8 *CachePtr;
UINT32 Offset;
UINT64 Lba;
UINT64 OverRunLba;
UINTN Amount;
Status = EFI_SUCCESS;
BufferPtr = Buffer;
BlockSize = PrivateData->BlockDevice[BlockDeviceNo].BlockSize;
//
// Read underrun
//
Lba = DivU64x32Remainder (StartingAddress, BlockSize, &Offset);
Status = FatGetCacheBlock (PrivateData, BlockDeviceNo, Lba, &CachePtr);
if (EFI_ERROR (Status)) {
return EFI_DEVICE_ERROR;
}
Amount = Size < (BlockSize - Offset) ? Size : (BlockSize - Offset);
CopyMem (BufferPtr, CachePtr + Offset, Amount);
if (Size == Amount) {
return EFI_SUCCESS;
}
Size -= Amount;
BufferPtr += Amount;
StartingAddress += Amount;
Lba += 1;
//
// Read aligned parts
//
OverRunLba = Lba + DivU64x32Remainder (Size, BlockSize, &Offset);
Size -= Offset;
Status = FatReadBlock (PrivateData, BlockDeviceNo, Lba, Size, BufferPtr);
if (EFI_ERROR (Status)) {
return EFI_DEVICE_ERROR;
}
BufferPtr += Size;
//
// Read overrun
//
if (Offset != 0) {
Status = FatGetCacheBlock (PrivateData, BlockDeviceNo, OverRunLba, &CachePtr);
if (EFI_ERROR (Status)) {
return EFI_DEVICE_ERROR;
}
CopyMem (BufferPtr, CachePtr, Offset);
}
return Status;
}
/**
This function finds Mbr partitions. Main algorithm
is ported from DXE partition driver.
@param PrivateData The global memory map
@param ParentBlockDevNo The parent block device
@retval TRUE New partitions are detected and logical block devices
are added to block device array
@retval FALSE No New partitions are added;
**/
BOOLEAN
FatFindMbrPartitions (
IN PEI_FAT_PRIVATE_DATA *PrivateData,
IN UINTN ParentBlockDevNo
)
{
EFI_STATUS Status;
MASTER_BOOT_RECORD *Mbr;
UINTN Index;
BOOLEAN Found;
PEI_FAT_BLOCK_DEVICE *ParentBlockDev;
PEI_FAT_BLOCK_DEVICE *BlockDev;
if (ParentBlockDevNo > PEI_FAT_MAX_BLOCK_DEVICE - 1) {
return FALSE;
}
ParentBlockDev = &(PrivateData->BlockDevice[ParentBlockDevNo]);
Found = FALSE;
Mbr = (MASTER_BOOT_RECORD *) PrivateData->BlockData;
Status = FatReadBlock (
PrivateData,
ParentBlockDevNo,
0,
ParentBlockDev->BlockSize,
Mbr
);
if (EFI_ERROR (Status) || !PartitionValidMbr (Mbr, ParentBlockDev->LastBlock)) {
goto Done;
}
//
// We have a valid mbr - add each partition
//
for (Index = 0; Index < MAX_MBR_PARTITIONS; Index++) {
if (Mbr->Partition[Index].OSIndicator == 0x00 || UNPACK_INT32 (Mbr->Partition[Index].SizeInLBA) == 0) {
//
// Don't use null MBR entries
//
continue;
}
//
// Register this partition
//
if (PrivateData->BlockDeviceCount < PEI_FAT_MAX_BLOCK_DEVICE) {
Found = TRUE;
BlockDev = &(PrivateData->BlockDevice[PrivateData->BlockDeviceCount]);
BlockDev->BlockSize = MBR_SIZE;
BlockDev->LastBlock = UNPACK_INT32 (Mbr->Partition[Index].SizeInLBA) - 1;
BlockDev->IoAlign = ParentBlockDev->IoAlign;
BlockDev->Logical = TRUE;
BlockDev->PartitionChecked = FALSE;
BlockDev->StartingPos = MultU64x32 (
UNPACK_INT32 (Mbr->Partition[Index].StartingLBA),
ParentBlockDev->BlockSize
);
BlockDev->ParentDevNo = ParentBlockDevNo;
PrivateData->BlockDeviceCount++;
}
}
Done:
ParentBlockDev->PartitionChecked = TRUE;
return Found;
}
/**
Find a cache block designated to specific Block device and Lba.
If not found, invalidate an oldest one and use it. (LRU cache)
@param PrivateData the global memory map.
@param BlockDeviceNo the Block device.
@param Lba the Logical Block Address
@param CachePtr Ptr to the starting address of the memory holding the
data;
@retval EFI_SUCCESS The function completed successfully.
@retval EFI_DEVICE_ERROR Something error while accessing media.
**/
EFI_STATUS
FatGetCacheBlock (
IN PEI_FAT_PRIVATE_DATA *PrivateData,
IN UINTN BlockDeviceNo,
IN UINT64 Lba,
OUT CHAR8 **CachePtr
)
{
EFI_STATUS Status;
PEI_FAT_CACHE_BUFFER *CacheBuffer;
INTN Index;
STATIC UINT8 Seed;
Status = EFI_SUCCESS;
CacheBuffer = NULL;
//
// go through existing cache buffers
//
for (Index = 0; Index < PEI_FAT_CACHE_SIZE; Index++) {
CacheBuffer = &(PrivateData->CacheBuffer[Index]);
if (CacheBuffer->Valid && CacheBuffer->BlockDeviceNo == BlockDeviceNo && CacheBuffer->Lba == Lba) {
break;
}
}
if (Index < PEI_FAT_CACHE_SIZE) {
*CachePtr = (CHAR8 *) CacheBuffer->Buffer;
return EFI_SUCCESS;
}
//
// We have to find an invalid cache buffer
//
for (Index = 0; Index < PEI_FAT_CACHE_SIZE; Index++) {
if (!PrivateData->CacheBuffer[Index].Valid) {
break;
}
}
//
// Use the cache buffer
//
if (Index == PEI_FAT_CACHE_SIZE) {
Index = (Seed++) % PEI_FAT_CACHE_SIZE;
}
//
// Current device ID should be less than maximum device ID.
//
if (BlockDeviceNo >= PEI_FAT_MAX_BLOCK_DEVICE) {
return EFI_DEVICE_ERROR;
}
CacheBuffer = &(PrivateData->CacheBuffer[Index]);
CacheBuffer->BlockDeviceNo = BlockDeviceNo;
CacheBuffer->Lba = Lba;
CacheBuffer->Size = PrivateData->BlockDevice[BlockDeviceNo].BlockSize;
//
// Read in the data
//
Status = FatReadBlock (
PrivateData,
BlockDeviceNo,
Lba,
CacheBuffer->Size,
CacheBuffer->Buffer
);
if (EFI_ERROR (Status)) {
return EFI_DEVICE_ERROR;
}
CacheBuffer->Valid = TRUE;
*CachePtr = (CHAR8 *) CacheBuffer->Buffer;
return Status;
}
