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- /*++
- Copyright (c) 2014 Minoca Corp. All Rights Reserved
- Module Name:
- disk.c
- Abstract:
- This module enumerates the disks found on BIOS systems.
- Author:
- Evan Green 20-Mar-2014
- Environment:
- Firmware
- --*/
- //
- // ------------------------------------------------------------------- Includes
- //
- #include <uefifw.h>
- #include <minoca/uefi/protocol/blockio.h>
- #include "biosfw.h"
- //
- // --------------------------------------------------------------------- Macros
- //
- //
- // This macro returns a pointer to the disk I/O data given a pointer to the
- // block I/O protocol instance.
- //
- #define EFI_PCAT_DISK_FROM_THIS(_BlockIo) \
- (EFI_PCAT_DISK *)((VOID *)(_BlockIo) - \
- ((VOID *)(&(((EFI_PCAT_DISK *)0)->BlockIo))))
- //
- // ---------------------------------------------------------------- Definitions
- //
- #define EFI_PCAT_DISK_MAGIC 0x73446350 // 'sDcP'
- //
- // Define the drive numbers to probe.
- //
- #define EFI_PCAT_HARD_DRIVE_START 0x80
- #define EFI_PCAT_HARD_DRIVE_COUNT 0x10
- #define EFI_PCAT_REMOVABLE_DRIVE_START 0x00
- #define EFI_PCAT_REMOVABLE_DRIVE_COUNT 0x10
- #define EFI_PCAT_MAX_SECTORS_PER_TRANSFER 0x08
- #define EFI_BIOS_BLOCK_IO_DEVICE_PATH_GUID \
- { \
- 0xCF31FAC5, 0xC24E, 0x11D2, \
- {0x85, 0xF3, 0x00, 0xA0, 0xC9, 0x3E, 0xC9, 0x3C} \
- }
- //
- // ------------------------------------------------------ Data Type Definitions
- //
- /*++
- Structure Description:
- This structure stores the disk I/O protocol's private context.
- Members:
- Magic - Stores the magic constand EFI_PCAT_DISK_MAGIC.
- Handle - Stores the handle to the block I/O device.
- DevicePath - Stores a pointer to the device path.
- DriveNumber - Stores the BIOS drive number of this disk.
- SectorSize - Stores the size of a block in this device.
- TotalSectors - Stores the count of sectors in this device.
- BlockIo - Stores the block I/O protocol.
- Media - Stores the block I/O media information.
- --*/
- typedef struct _EFI_PCAT_DISK {
- UINT32 Magic;
- EFI_HANDLE Handle;
- EFI_DEVICE_PATH_PROTOCOL *DevicePath;
- UINT8 DriveNumber;
- UINT32 SectorSize;
- UINT64 TotalSectors;
- EFI_BLOCK_IO_PROTOCOL BlockIo;
- EFI_BLOCK_IO_MEDIA Media;
- } EFI_PCAT_DISK, *PEFI_PCAT_DISK;
- /*++
- Structure Description:
- This structure defines the BIOS block I/O device path.
- Members:
- DevicePath - Stores the standard vendor-specific device path.
- DriveNumber - Stores the BIOS drive number.
- --*/
- typedef struct _EFI_BIOS_BLOCK_IO_DEVICE_PATH {
- VENDOR_DEVICE_PATH DevicePath;
- UINT8 DriveNumber;
- } EFI_BIOS_BLOCK_IO_DEVICE_PATH, *PEFI_BIOS_BLOCK_IO_DEVICE_PATH;
- /*++
- Structure Description:
- This structure defines the BIOS block I/O device path.
- Members:
- DevicePath - Stores the standard vendor-specific device path.
- DriveNumber - Stores the BIOS drive number.
- --*/
- typedef struct _EFI_PCAT_DISK_DEVICE_PATH {
- EFI_BIOS_BLOCK_IO_DEVICE_PATH Disk;
- EFI_DEVICE_PATH_PROTOCOL End;
- } PACKED EFI_PCAT_DISK_DEVICE_PATH, *PEFI_PCAT_DISK_DEVICE_PATH;
- //
- // ----------------------------------------------- Internal Function Prototypes
- //
- EFIAPI
- EFI_STATUS
- EfipPcatDiskReset (
- EFI_BLOCK_IO_PROTOCOL *This,
- BOOLEAN ExtendedVerification
- );
- EFIAPI
- EFI_STATUS
- EfipPcatDiskReadBlocks (
- EFI_BLOCK_IO_PROTOCOL *This,
- UINT32 MediaId,
- EFI_LBA Lba,
- UINTN BufferSize,
- VOID *Buffer
- );
- EFIAPI
- EFI_STATUS
- EfipPcatDiskWriteBlocks (
- EFI_BLOCK_IO_PROTOCOL *This,
- UINT32 MediaId,
- EFI_LBA Lba,
- UINTN BufferSize,
- VOID *Buffer
- );
- EFIAPI
- EFI_STATUS
- EfipPcatDiskFlushBlocks (
- EFI_BLOCK_IO_PROTOCOL *This
- );
- EFI_STATUS
- EfipPcatProbeDrive (
- UINTN DriveNumber
- );
- EFI_STATUS
- EfipPcatGetDiskParameters (
- UINT8 DriveNumber,
- UINT64 *SectorCount,
- UINT32 *SectorSize
- );
- EFI_STATUS
- EfipPcatBlockOperation (
- PEFI_PCAT_DISK Disk,
- BOOLEAN Write,
- VOID *Buffer,
- UINT32 AbsoluteSector,
- UINT32 SectorCount
- );
- EFI_STATUS
- EfipPcatResetDisk (
- UINT8 DriveNumber
- );
- //
- // -------------------------------------------------------------------- Globals
- //
- //
- // Define the private data template.
- //
- EFI_PCAT_DISK EfiPcatDiskTemplate = {
- EFI_PCAT_DISK_MAGIC,
- NULL,
- NULL,
- 0xFF,
- 0,
- 0,
- {
- EFI_BLOCK_IO_PROTOCOL_REVISION3,
- NULL,
- EfipPcatDiskReset,
- EfipPcatDiskReadBlocks,
- EfipPcatDiskWriteBlocks,
- EfipPcatDiskFlushBlocks
- }
- };
- //
- // Define the device path template.
- //
- EFI_PCAT_DISK_DEVICE_PATH EfiPcatDevicePathTemplate = {
- {
- {
- {
- HARDWARE_DEVICE_PATH,
- HW_VENDOR_DP,
- sizeof(EFI_BIOS_BLOCK_IO_DEVICE_PATH)
- },
- EFI_BIOS_BLOCK_IO_DEVICE_PATH_GUID,
- },
- 0xFF
- },
- {
- END_DEVICE_PATH_TYPE,
- END_ENTIRE_DEVICE_PATH_SUBTYPE,
- END_DEVICE_PATH_LENGTH
- }
- };
- //
- // ------------------------------------------------------------------ Functions
- //
- EFI_STATUS
- EfipPcatEnumerateDisks (
- VOID
- )
- /*++
- Routine Description:
- This routine enumerates all the disks it can find on a BIOS machine.
- Arguments:
- None.
- Return Value:
- EFI Status code.
- --*/
- {
- UINTN DriveIndex;
- EFI_STATUS Status;
- for (DriveIndex = 0;
- DriveIndex < EFI_PCAT_HARD_DRIVE_COUNT;
- DriveIndex += 1) {
- Status = EfipPcatProbeDrive(DriveIndex + EFI_PCAT_HARD_DRIVE_START);
- if (EFI_ERROR(Status)) {
- break;
- }
- }
- for (DriveIndex = 0;
- DriveIndex < EFI_PCAT_REMOVABLE_DRIVE_COUNT;
- DriveIndex += 1) {
- Status = EfipPcatProbeDrive(
- DriveIndex + EFI_PCAT_REMOVABLE_DRIVE_START);
- if (EFI_ERROR(Status)) {
- break;
- }
- }
- return EFI_SUCCESS;
- }
- //
- // --------------------------------------------------------- Internal Functions
- //
- EFIAPI
- EFI_STATUS
- EfipPcatDiskReset (
- EFI_BLOCK_IO_PROTOCOL *This,
- BOOLEAN ExtendedVerification
- )
- /*++
- Routine Description:
- This routine resets the block device.
- Arguments:
- This - Supplies a pointer to the protocol instance.
- ExtendedVerification - Supplies a boolean indicating whether or not the
- driver should perform diagnostics on reset.
- Return Value:
- EFI_SUCCESS on success.
- EFI_DEVICE_ERROR if the device had an error and could not complete the
- request.
- --*/
- {
- PEFI_PCAT_DISK Disk;
- Disk = EFI_PCAT_DISK_FROM_THIS(This);
- return EfipPcatResetDisk(Disk->DriveNumber);
- }
- EFIAPI
- EFI_STATUS
- EfipPcatDiskReadBlocks (
- EFI_BLOCK_IO_PROTOCOL *This,
- UINT32 MediaId,
- EFI_LBA Lba,
- UINTN BufferSize,
- VOID *Buffer
- )
- /*++
- Routine Description:
- This routine performs a block I/O read from the device.
- Arguments:
- This - Supplies a pointer to the protocol instance.
- MediaId - Supplies the media identifier, which changes each time the media
- is replaced.
- Lba - Supplies the logical block address of the read.
- BufferSize - Supplies the size of the buffer in bytes.
- Buffer - Supplies the buffer where the read data will be returned.
- Return Value:
- EFI_SUCCESS on success.
- EFI_DEVICE_ERROR if the device had an error and could not complete the
- request.
- EFI_NO_MEDIA if there is no media in the device.
- EFI_MEDIA_CHANGED if the media ID does not match the current device.
- EFI_BAD_BUFFER_SIZE if the buffer was not a multiple of the device block
- size.
- EFI_INVALID_PARAMETER if the read request contains LBAs that are not valid,
- or the buffer is not properly aligned.
- --*/
- {
- PEFI_PCAT_DISK Disk;
- UINTN SectorCount;
- UINTN SectorsThisRound;
- EFI_STATUS Status;
- Disk = EFI_PCAT_DISK_FROM_THIS(This);
- if (MediaId != Disk->Media.MediaId) {
- return EFI_MEDIA_CHANGED;
- }
- if (Disk->Media.MediaPresent == FALSE) {
- return EFI_NO_MEDIA;
- }
- Status = EFI_SUCCESS;
- SectorCount = BufferSize / Disk->SectorSize;
- while (SectorCount != 0) {
- SectorsThisRound = EFI_PCAT_MAX_SECTORS_PER_TRANSFER;
- if (SectorsThisRound > SectorCount) {
- SectorsThisRound = SectorCount;
- }
- Status = EfipPcatBlockOperation(Disk,
- FALSE,
- Buffer,
- (UINT32)Lba,
- SectorsThisRound);
- if (EFI_ERROR(Status)) {
- break;
- }
- Lba += SectorsThisRound;
- Buffer += SectorsThisRound * Disk->SectorSize;
- SectorCount -= SectorsThisRound;
- }
- return Status;
- }
- EFIAPI
- EFI_STATUS
- EfipPcatDiskWriteBlocks (
- EFI_BLOCK_IO_PROTOCOL *This,
- UINT32 MediaId,
- EFI_LBA Lba,
- UINTN BufferSize,
- VOID *Buffer
- )
- /*++
- Routine Description:
- This routine performs a block I/O write to the device.
- Arguments:
- This - Supplies a pointer to the protocol instance.
- MediaId - Supplies the media identifier, which changes each time the media
- is replaced.
- Lba - Supplies the logical block address of the write.
- BufferSize - Supplies the size of the buffer in bytes.
- Buffer - Supplies the buffer containing the data to write.
- Return Value:
- EFI_SUCCESS on success.
- EFI_WRITE_PROTECTED if the device cannot be written to.
- EFI_DEVICE_ERROR if the device had an error and could not complete the
- request.
- EFI_NO_MEDIA if there is no media in the device.
- EFI_MEDIA_CHANGED if the media ID does not match the current device.
- EFI_BAD_BUFFER_SIZE if the buffer was not a multiple of the device block
- size.
- EFI_INVALID_PARAMETER if the read request contains LBAs that are not valid,
- or the buffer is not properly aligned.
- --*/
- {
- PEFI_PCAT_DISK Disk;
- UINTN SectorCount;
- UINTN SectorsThisRound;
- EFI_STATUS Status;
- Disk = EFI_PCAT_DISK_FROM_THIS(This);
- if (MediaId != Disk->Media.MediaId) {
- return EFI_MEDIA_CHANGED;
- }
- if (Disk->Media.MediaPresent == FALSE) {
- return EFI_NO_MEDIA;
- }
- Status = EFI_SUCCESS;
- SectorCount = BufferSize / Disk->SectorSize;
- while (SectorCount != 0) {
- SectorsThisRound = EFI_PCAT_MAX_SECTORS_PER_TRANSFER;
- if (SectorsThisRound > SectorCount) {
- SectorsThisRound = SectorCount;
- }
- Status = EfipPcatBlockOperation(Disk,
- TRUE,
- Buffer,
- (UINT32)Lba,
- SectorsThisRound);
- if (EFI_ERROR(Status)) {
- break;
- }
- Lba += SectorsThisRound;
- Buffer += SectorsThisRound * Disk->SectorSize;
- SectorCount -= SectorsThisRound;
- }
- return Status;
- }
- EFIAPI
- EFI_STATUS
- EfipPcatDiskFlushBlocks (
- EFI_BLOCK_IO_PROTOCOL *This
- )
- /*++
- Routine Description:
- This routine flushes the block device.
- Arguments:
- This - Supplies a pointer to the protocol instance.
- Return Value:
- EFI_SUCCESS on success.
- EFI_DEVICE_ERROR if the device had an error and could not complete the
- request.
- EFI_NO_MEDIA if there is no media in the device.
- --*/
- {
- return EFI_SUCCESS;
- }
- EFI_STATUS
- EfipPcatProbeDrive (
- UINTN DriveNumber
- )
- /*++
- Routine Description:
- This routine probes the given drive number and creates a device handle if
- there is a drive there.
- Arguments:
- DriveNumber - Supplies the drive number to probe.
- Return Value:
- EFI Status code.
- --*/
- {
- PEFI_PCAT_DISK_DEVICE_PATH DevicePath;
- PEFI_PCAT_DISK Disk;
- UINT64 SectorCount;
- UINT32 SectorSize;
- EFI_STATUS Status;
- Status = EfipPcatGetDiskParameters(DriveNumber, &SectorCount, &SectorSize);
- if (EFI_ERROR(Status)) {
- return Status;
- }
- //
- // There's a disk there. Allocate a data structure for it.
- //
- Status = EfiAllocatePool(EfiBootServicesData,
- sizeof(EFI_PCAT_DISK),
- (VOID **)&Disk);
- if (EFI_ERROR(Status)) {
- return Status;
- }
- EfiCopyMem(Disk, &EfiPcatDiskTemplate, sizeof(EFI_PCAT_DISK));
- Disk->Handle = NULL;
- Disk->DriveNumber = DriveNumber;
- Disk->SectorSize = SectorSize;
- Disk->TotalSectors = SectorCount;
- Disk->BlockIo.Media = &(Disk->Media);
- if (DriveNumber < EFI_PCAT_HARD_DRIVE_START) {
- Disk->Media.RemovableMedia = TRUE;
- }
- Disk->Media.MediaPresent = TRUE;
- Disk->Media.BlockSize = SectorSize;
- Disk->Media.LastBlock = SectorCount - 1;
- Status = EfiAllocatePool(EfiBootServicesData,
- sizeof(EFI_PCAT_DISK_DEVICE_PATH),
- (VOID **)&DevicePath);
- if (EFI_ERROR(Status)) {
- EfiFreePool(Disk);
- return Status;
- }
- EfiCopyMem(DevicePath,
- &EfiPcatDevicePathTemplate,
- sizeof(EFI_PCAT_DISK_DEVICE_PATH));
- DevicePath->Disk.DriveNumber = DriveNumber;
- Disk->DevicePath = (EFI_DEVICE_PATH_PROTOCOL *)DevicePath;
- Status = EfiInstallMultipleProtocolInterfaces(&(Disk->Handle),
- &EfiDevicePathProtocolGuid,
- Disk->DevicePath,
- &EfiBlockIoProtocolGuid,
- &(Disk->BlockIo),
- NULL);
- return Status;
- }
- EFI_STATUS
- EfipPcatGetDiskParameters (
- UINT8 DriveNumber,
- UINT64 *SectorCount,
- UINT32 *SectorSize
- )
- /*++
- Routine Description:
- This routine uses the BIOS to determine the geometry for the given disk.
- Arguments:
- DriveNumber - Supplies the drive number of the disk to query. Valid values
- are:
- 0x80 - Boot drive.
- 0x81, ... - Additional hard drives
- 0x0, ... - Floppy drives.
- SectorCount - Supplies a pointer where the total number of sectors will be
- returned (one beyond the last valid LBA).
- SectorSize - Supplies a pointer where the size of a sector will be returned
- on success.
- Return Value:
- STATUS_SUCCESS if the operation completed successfully.
- STATUS_FIRMWARE_ERROR if the BIOS returned an error.
- Other error codes.
- --*/
- {
- UINTN BufferAddress;
- PINT13_EXTENDED_DRIVE_PARAMETERS Parameters;
- BIOS_CALL_CONTEXT RealModeContext;
- EFI_STATUS Status;
- //
- // Create a standard BIOS call context.
- //
- Status = EfipCreateBiosCallContext(&RealModeContext, 0x13);
- if (EFI_ERROR(Status)) {
- goto GetDiskGeometryEnd;
- }
- //
- // Int 13 function 8 is "Get disk parameters". Ah takes the function number
- // (8), and dl takes the drive number.
- //
- RealModeContext.Eax = INT13_EXTENDED_GET_DRIVE_PARAMETERS << 8;
- RealModeContext.Edx = DriveNumber;
- RealModeContext.Ds = 0;
- BufferAddress = (UINTN)(RealModeContext.DataPage);
- RealModeContext.Esi = (UINT16)BufferAddress;
- Parameters = (PINT13_EXTENDED_DRIVE_PARAMETERS)(UINTN)BufferAddress;
- EfiSetMem(Parameters, sizeof(INT13_EXTENDED_DRIVE_PARAMETERS), 0);
- Parameters->PacketSize = sizeof(INT13_EXTENDED_DRIVE_PARAMETERS);
- //
- // Execute the firmware call.
- //
- EfipExecuteBiosCall(&RealModeContext);
- //
- // Check for an error. The status code is in Ah.
- //
- if (((RealModeContext.Eax & 0xFF00) != 0) ||
- ((RealModeContext.Eflags & IA32_EFLAG_CF) != 0)) {
- Status = EFI_NOT_FOUND;
- goto GetDiskGeometryEnd;
- }
- *SectorCount = Parameters->TotalSectorCount;
- *SectorSize = Parameters->SectorSize;
- Status = EFI_SUCCESS;
- GetDiskGeometryEnd:
- EfipDestroyBiosCallContext(&RealModeContext);
- return Status;
- }
- EFI_STATUS
- EfipPcatBlockOperation (
- PEFI_PCAT_DISK Disk,
- BOOLEAN Write,
- VOID *Buffer,
- UINT32 AbsoluteSector,
- UINT32 SectorCount
- )
- /*++
- Routine Description:
- This routine uses the BIOS to read from or write to the disk.
- Arguments:
- Disk - Supplies a pointer to the disk to operate on.
- Write - Supplies a boolean indicating if this is a read (FALSE) or write
- (TRUE) operation.
- Buffer - Supplies the buffer either containing the data to write or where
- the read data will be returned.
- AbsoluteSector - Supplies the zero-based sector number to read from.
- SectorCount - Supplies the number of sectors to read. The supplied buffer
- must be at least this large.
- Return Value:
- STATUS_SUCCESS if the operation completed successfully.
- STATUS_FIRMWARE_ERROR if the BIOS returned an error.
- Other error codes.
- --*/
- {
- UINTN RealModeBuffer;
- BIOS_CALL_CONTEXT RealModeContext;
- PINT13_DISK_ACCESS_PACKET Request;
- EFI_STATUS Status;
- //
- // Create a standard BIOS call context.
- //
- Status = EfipCreateBiosCallContext(&RealModeContext, 0x13);
- if (EFI_ERROR(Status)) {
- goto BlockOperationEnd;
- }
- //
- // Create the disk access packet on the stack.
- //
- Request = (PINT13_DISK_ACCESS_PACKET)(RealModeContext.Esp -
- sizeof(INT13_DISK_ACCESS_PACKET));
- Request->PacketSize = sizeof(INT13_DISK_ACCESS_PACKET);
- Request->Reserved = 0;
- Request->BlockCount = SectorCount;
- RealModeBuffer = (UINTN)(RealModeContext.DataPage);
- Request->TransferBuffer = (UINTN)RealModeBuffer;
- Request->BlockAddress = AbsoluteSector;
- RealModeContext.Edx = Disk->DriveNumber;
- RealModeContext.Esp = (UINTN)Request;
- RealModeContext.Esi = (UINTN)Request;
- if (Write != FALSE) {
- RealModeContext.Eax = INT13_EXTENDED_WRITE << 8;
- EfiCopyMem((VOID *)RealModeBuffer,
- Buffer,
- SectorCount * Disk->SectorSize);
- } else {
- RealModeContext.Eax = INT13_EXTENDED_READ << 8;
- }
- //
- // Execute the firmware call.
- //
- EfipExecuteBiosCall(&RealModeContext);
- //
- // Check for an error (carry flag set). The status code is in Ah.
- //
- if (((RealModeContext.Eax & 0xFF00) != 0) ||
- ((RealModeContext.Eflags & IA32_EFLAG_CF) != 0)) {
- Status = EFI_DEVICE_ERROR;
- goto BlockOperationEnd;
- }
- //
- // Copy the data over from the real mode data page to the caller's buffer.
- //
- if (Write == FALSE) {
- EfiCopyMem(Buffer,
- (VOID *)RealModeBuffer,
- SectorCount * Disk->SectorSize);
- }
- Status = EFI_SUCCESS;
- BlockOperationEnd:
- EfipDestroyBiosCallContext(&RealModeContext);
- return Status;
- }
- EFI_STATUS
- EfipPcatResetDisk (
- UINT8 DriveNumber
- )
- /*++
- Routine Description:
- This routine uses the BIOS to reset the disk.
- Arguments:
- DriveNumber - Supplies the drive number of the disk to reset. Valid values
- are:
- 0x80 - Boot drive.
- 0x81, ... - Additional hard drives
- 0x0, ... - Floppy drives.
- Return Value:
- STATUS_SUCCESS if the operation completed successfully.
- STATUS_FIRMWARE_ERROR if the BIOS returned an error.
- Other error codes.
- --*/
- {
- BIOS_CALL_CONTEXT RealModeContext;
- EFI_STATUS Status;
- //
- // Create a standard BIOS call context.
- //
- Status = EfipCreateBiosCallContext(&RealModeContext, 0x13);
- if (EFI_ERROR(Status)) {
- goto PcatResetDiskEnd;
- }
- //
- // Int 13 function zero is reset.
- //
- RealModeContext.Eax = INT13_EXTENDED_GET_DRIVE_PARAMETERS << 8;
- RealModeContext.Edx = DriveNumber;
- //
- // Execute the firmware call.
- //
- EfipExecuteBiosCall(&RealModeContext);
- //
- // Check for an error. The status code is in Ah.
- //
- if (((RealModeContext.Eax & 0xFF00) != 0) ||
- ((RealModeContext.Eflags & IA32_EFLAG_CF) != 0)) {
- Status = EFI_DEVICE_ERROR;
- goto PcatResetDiskEnd;
- }
- Status = EFI_SUCCESS;
- PcatResetDiskEnd:
- EfipDestroyBiosCallContext(&RealModeContext);
- return Status;
- }
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