audk/FatPkg/EnhancedFatDxe/Fat.c

/*++

Copyright (c) 2005 - 2007, Intel Corporation
All rights reserved. This program and the accompanying materials are licensed and made available
under the terms and conditions of the BSD License which accompanies this
distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.


Module Name:

  Fat.c

Abstract:

  Fat File System driver routines that support EFI driver model

--*/

#include "Fat.h"

EFI_STATUS
EFIAPI
FatEntryPoint (
  IN EFI_HANDLE         ImageHandle,
  IN EFI_SYSTEM_TABLE   *SystemTable
  );

EFI_STATUS
EFIAPI
FatUnload (
  IN EFI_HANDLE         ImageHandle
  );

EFI_STATUS
EFIAPI
FatDriverBindingSupported (
  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN EFI_HANDLE                   Controller,
  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
  );

EFI_STATUS
EFIAPI
FatDriverBindingStart (
  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN EFI_HANDLE                   Controller,
  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
  );

EFI_STATUS
EFIAPI
FatDriverBindingStop (
  IN  EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN  EFI_HANDLE                   Controller,
  IN  UINTN                        NumberOfChildren,
  IN  EFI_HANDLE                   *ChildHandleBuffer
  );

//
// DriverBinding protocol instance
//
EFI_DRIVER_BINDING_PROTOCOL gFatDriverBinding = {
  FatDriverBindingSupported,
  FatDriverBindingStart,
  FatDriverBindingStop,
  0xa,
  NULL,
  NULL
};

EFI_STATUS
EFIAPI
FatEntryPoint (
  IN EFI_HANDLE         ImageHandle,
  IN EFI_SYSTEM_TABLE   *SystemTable
  )
/*++

Routine Description:

  Register Driver Binding protocol for this driver.

Arguments:

  ImageHandle           - Handle for the image of this driver.
  SystemTable           - Pointer to the EFI System Table.

Returns:

  EFI_SUCCESS           - Driver loaded.
  other                 - Driver not loaded.

--*/
{
  EFI_STATUS                Status;

  //
  // Initialize the EFI Driver Library
  //
  Status = EfiLibInstallDriverBindingComponentName2 (
             ImageHandle,
             SystemTable,
             &gFatDriverBinding,
             ImageHandle,
             &gFatComponentName,
             &gFatComponentName2
             );
  ASSERT_EFI_ERROR (Status);

  return Status;
}

EFI_STATUS
EFIAPI
FatUnload (
  IN EFI_HANDLE  ImageHandle
  )
/*++

Routine Description:

  Unload function for this image. Uninstall DriverBinding protocol.

Arguments:

  ImageHandle           - Handle for the image of this driver.

Returns:

  EFI_SUCCESS           - Driver unloaded successfully.
  other                 - Driver can not unloaded.

--*/
{
  EFI_STATUS  Status;
  EFI_HANDLE  *DeviceHandleBuffer;
  UINTN       DeviceHandleCount;
  UINTN       Index;

  Status = gBS->LocateHandleBuffer (
                  AllHandles,
                  NULL,
                  NULL,
                  &DeviceHandleCount,
                  &DeviceHandleBuffer
                  );
  if (!EFI_ERROR (Status)) {
    for (Index = 0; Index < DeviceHandleCount; Index++) {
      Status = gBS->DisconnectController (
                      DeviceHandleBuffer[Index],
                      ImageHandle,
                      NULL
                      );
    }

    if (DeviceHandleBuffer != NULL) {
      FreePool (DeviceHandleBuffer);
    }
  }

  return Status;
}

EFI_STATUS
EFIAPI
FatDriverBindingSupported (
  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN EFI_HANDLE                   ControllerHandle,
  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
  )
/*++

Routine Description:

  Test to see if this driver can add a file system to ControllerHandle.
  ControllerHandle must support both Disk IO and Block IO protocols.

Arguments:

  This                  - Protocol instance pointer.
  ControllerHandle      - Handle of device to test.
  RemainingDevicePath   - Not used.

Returns:

  EFI_SUCCESS           - This driver supports this device.
  EFI_ALREADY_STARTED   - This driver is already running on this device.
  other                 - This driver does not support this device.

--*/
{
  EFI_STATUS            Status;
  EFI_DISK_IO_PROTOCOL  *DiskIo;

  //
  // Open the IO Abstraction(s) needed to perform the supported test
  //
  Status = gBS->OpenProtocol (
                  ControllerHandle,
                  &gEfiDiskIoProtocolGuid,
                  (VOID **) &DiskIo,
                  This->DriverBindingHandle,
                  ControllerHandle,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );

  if (EFI_ERROR (Status)) {
    return Status;
  }
  //
  // Close the I/O Abstraction(s) used to perform the supported test
  //
  gBS->CloseProtocol (
         ControllerHandle,
         &gEfiDiskIoProtocolGuid,
         This->DriverBindingHandle,
         ControllerHandle
         );

  //
  // Open the IO Abstraction(s) needed to perform the supported test
  //
  Status = gBS->OpenProtocol (
                  ControllerHandle,
                  &gEfiBlockIoProtocolGuid,
                  NULL,
                  This->DriverBindingHandle,
                  ControllerHandle,
                  EFI_OPEN_PROTOCOL_TEST_PROTOCOL
                  );

  return Status;
}

EFI_STATUS
EFIAPI
FatDriverBindingStart (
  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN EFI_HANDLE                   ControllerHandle,
  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
  )
/*++

Routine Description:

  Start this driver on ControllerHandle by opening a Block IO and Disk IO
  protocol, reading Device Path. Add a Simple File System protocol to
  ControllerHandle if the media contains a valid file system.

Arguments:

  This                  - Protocol instance pointer.
  ControllerHandle      - Handle of device to bind driver to.
  RemainingDevicePath   - Not used.

Returns:

  EFI_SUCCESS           - This driver is added to DeviceHandle.
  EFI_ALREADY_STARTED   - This driver is already running on DeviceHandle.
  EFI_OUT_OF_RESOURCES  - Can not allocate the memory.
  other                 - This driver does not support this device.

--*/
{
  EFI_STATUS            Status;
  EFI_BLOCK_IO_PROTOCOL *BlockIo;
  EFI_DISK_IO_PROTOCOL  *DiskIo;

  Status = InitializeUnicodeCollationSupport (This->DriverBindingHandle);
  if (EFI_ERROR (Status)) {
    return Status;
  }
  //
  // Open our required BlockIo and DiskIo
  //
  Status = gBS->OpenProtocol (
                  ControllerHandle,
                  &gEfiBlockIoProtocolGuid,
                  (VOID **) &BlockIo,
                  This->DriverBindingHandle,
                  ControllerHandle,
                  EFI_OPEN_PROTOCOL_GET_PROTOCOL
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  Status = gBS->OpenProtocol (
                  ControllerHandle,
                  &gEfiDiskIoProtocolGuid,
                  (VOID **) &DiskIo,
                  This->DriverBindingHandle,
                  ControllerHandle,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }
  //
  // Allocate Volume structure. In FatAllocateVolume(), Resources
  // are allocated with protocol installed and cached initialized
  //
  Status = FatAllocateVolume (ControllerHandle, DiskIo, BlockIo);

  //
  // When the media changes on a device it will Reinstall the BlockIo interaface.
  // This will cause a call to our Stop(), and a subsequent reentrant call to our
  // Start() successfully. We should leave the device open when this happen.
  //
  if (EFI_ERROR (Status)) {
    Status = gBS->OpenProtocol (
                    ControllerHandle,
                    &gEfiSimpleFileSystemProtocolGuid,
                    NULL,
                    This->DriverBindingHandle,
                    ControllerHandle,
                    EFI_OPEN_PROTOCOL_TEST_PROTOCOL
                    );
    if (EFI_ERROR (Status)) {
      gBS->CloseProtocol (
             ControllerHandle,
             &gEfiDiskIoProtocolGuid,
             This->DriverBindingHandle,
             ControllerHandle
             );
    }
  }

  return Status;
}

EFI_STATUS
EFIAPI
FatDriverBindingStop (
  IN  EFI_DRIVER_BINDING_PROTOCOL   *This,
  IN  EFI_HANDLE                    ControllerHandle,
  IN  UINTN                         NumberOfChildren,
  IN  EFI_HANDLE                    *ChildHandleBuffer
  )
/*++

Routine Description:
  Stop this driver on ControllerHandle.

Arguments:
  This                  - Protocol instance pointer.
  ControllerHandle      - Handle of device to stop driver on.
  NumberOfChildren      - Not used.
  ChildHandleBuffer     - Not used.

Returns:
  EFI_SUCCESS           - This driver is removed DeviceHandle.
  other                 - This driver was not removed from this device.

--*/
{
  EFI_STATUS                      Status;
  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *FileSystem;
  FAT_VOLUME                      *Volume;

  //
  // Get our context back
  //
  Status = gBS->OpenProtocol (
                  ControllerHandle,
                  &gEfiSimpleFileSystemProtocolGuid,
                  (VOID **) &FileSystem,
                  This->DriverBindingHandle,
                  ControllerHandle,
                  EFI_OPEN_PROTOCOL_GET_PROTOCOL
                  );

  if (!EFI_ERROR (Status)) {
    Volume = VOLUME_FROM_VOL_INTERFACE (FileSystem);
    Status = FatAbandonVolume (Volume);
    if (EFI_ERROR (Status)) {
      return Status;
    }
  }

  Status = gBS->CloseProtocol (
                  ControllerHandle,
                  &gEfiDiskIoProtocolGuid,
                  This->DriverBindingHandle,
                  ControllerHandle
                  );

  return Status;
}