/** @file
Internal definitions for the virtio-blk driver, which produces Block I/O
Protocol instances for virtio-blk devices.
Copyright (C) 2012, Red Hat, Inc.
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.
**/
#ifndef _VIRTIO_BLK_DXE_H_
#define _VIRTIO_BLK_DXE_H_
#include <Protocol/BlockIo.h>
#include <Protocol/ComponentName.h>
#include <Protocol/DriverBinding.h>
#include <IndustryStandard/Virtio.h>
#define VBLK_SIG SIGNATURE_32 ('V', 'B', 'L', 'K')
typedef struct {
//
// Parts of this structure are initialized / torn down in various functions
// at various call depths. The table to the right should make it easier to
// track them.
//
// field init function init dpth
// --------------------- ------------------ ---------
UINT32 Signature; // DriverBindingStart 0
VIRTIO_DEVICE_PROTOCOL *VirtIo; // DriverBindingStart 0
EFI_EVENT ExitBoot; // DriverBindingStart 0
VRING Ring; // VirtioRingInit 2
EFI_BLOCK_IO_PROTOCOL BlockIo; // VirtioBlkInit 1
EFI_BLOCK_IO_MEDIA BlockIoMedia; // VirtioBlkInit 1
} VBLK_DEV;
#define VIRTIO_BLK_FROM_BLOCK_IO(BlockIoPointer) \
CR (BlockIoPointer, VBLK_DEV, BlockIo, VBLK_SIG)
/**
Device probe function for this driver.
The DXE core calls this function for any given device in order to see if the
driver can drive the device.
Specs relevant in the general sense:
- UEFI Spec 2.3.1 + Errata C:
- 6.3 Protocol Handler Services -- for accessing the underlying device
- 10.1 EFI Driver Binding Protocol -- for exporting ourselves
- Driver Writer's Guide for UEFI 2.3.1 v1.01:
- 5.1.3.4 OpenProtocol() and CloseProtocol() -- for accessing the
underlying device
- 9 Driver Binding Protocol -- for exporting ourselves
@param[in] This The EFI_DRIVER_BINDING_PROTOCOL object
incorporating this driver (independently of
any device).
@param[in] DeviceHandle The device to probe.
@param[in] RemainingDevicePath Relevant only for bus drivers, ignored.
@retval EFI_SUCCESS The driver supports the device being probed.
@retval EFI_UNSUPPORTED Based on virtio-blk discovery, we do not support
the device.
@return Error codes from the OpenProtocol() boot service.
**/
EFI_STATUS
EFIAPI
VirtioBlkDriverBindingSupported (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE DeviceHandle,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
);
/**
After we've pronounced support for a specific device in
DriverBindingSupported(), we start managing said device (passed in by the
Driver Exeuction Environment) with the following service.
See DriverBindingSupported() for specification references.
@param[in] This The EFI_DRIVER_BINDING_PROTOCOL object
incorporating this driver (independently of
any device).
@param[in] DeviceHandle The supported device to drive.
@param[in] RemainingDevicePath Relevant only for bus drivers, ignored.
@retval EFI_SUCCESS Driver instance has been created and
initialized for the virtio-blk device, it
is now accessibla via EFI_BLOCK_IO_PROTOCOL.
@retval EFI_OUT_OF_RESOURCES Memory allocation failed.
@return Error codes from the OpenProtocol() boot
service, VirtioBlkInit(), or the
InstallProtocolInterface() boot service.
**/
EFI_STATUS
EFIAPI
VirtioBlkDriverBindingStart (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE DeviceHandle,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
);
/**
Stop driving a virtio-blk device and remove its BlockIo interface.
This function replays the success path of DriverBindingStart() in reverse.
The host side virtio-blk device is reset, so that the OS boot loader or the
OS may reinitialize it.
@param[in] This The EFI_DRIVER_BINDING_PROTOCOL object
incorporating this driver (independently of any
device).
@param[in] DeviceHandle Stop driving this device.
@param[in] NumberOfChildren Since this function belongs to a device driver
only (as opposed to a bus driver), the caller
environment sets NumberOfChildren to zero, and
we ignore it.
@param[in] ChildHandleBuffer Ignored (corresponding to NumberOfChildren).
**/
EFI_STATUS
EFIAPI
VirtioBlkDriverBindingStop (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE DeviceHandle,
IN UINTN NumberOfChildren,
IN EFI_HANDLE *ChildHandleBuffer
);
//
// UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol
// Driver Writer's Guide for UEFI 2.3.1 v1.01,
// 24.2 Block I/O Protocol Implementations
//
EFI_STATUS
EFIAPI
VirtioBlkReset (
IN EFI_BLOCK_IO_PROTOCOL *This,
IN BOOLEAN ExtendedVerification
);
/**
ReadBlocks() operation for virtio-blk.
See
- UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol, 12.8 EFI Block I/O
Protocol, EFI_BLOCK_IO_PROTOCOL.ReadBlocks().
- Driver Writer's Guide for UEFI 2.3.1 v1.01, 24.2.2. ReadBlocks() and
ReadBlocksEx() Implementation.
Parameter checks and conformant return values are implemented in
VerifyReadWriteRequest() and SynchronousRequest().
A zero BufferSize doesn't seem to be prohibited, so do nothing in that case,
successfully.
**/
EFI_STATUS
EFIAPI
VirtioBlkReadBlocks (
IN EFI_BLOCK_IO_PROTOCOL *This,
IN UINT32 MediaId,
IN EFI_LBA Lba,
IN UINTN BufferSize,
OUT VOID *Buffer
);
/**
WriteBlocks() operation for virtio-blk.
See
- UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol, 12.8 EFI Block I/O
Protocol, EFI_BLOCK_IO_PROTOCOL.WriteBlocks().
- Driver Writer's Guide for UEFI 2.3.1 v1.01, 24.2.3 WriteBlocks() and
WriteBlockEx() Implementation.
Parameter checks and conformant return values are implemented in
VerifyReadWriteRequest() and SynchronousRequest().
A zero BufferSize doesn't seem to be prohibited, so do nothing in that case,
successfully.
**/
EFI_STATUS
EFIAPI
VirtioBlkWriteBlocks (
IN EFI_BLOCK_IO_PROTOCOL *This,
IN UINT32 MediaId,
IN EFI_LBA Lba,
IN UINTN BufferSize,
IN VOID *Buffer
);
/**
FlushBlocks() operation for virtio-blk.
See
- UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol, 12.8 EFI Block I/O
Protocol, EFI_BLOCK_IO_PROTOCOL.FlushBlocks().
- Driver Writer's Guide for UEFI 2.3.1 v1.01, 24.2.4 FlushBlocks() and
FlushBlocksEx() Implementation.
If the underlying virtio-blk device doesn't support flushing (ie.
write-caching), then this function should not be called by higher layers,
according to EFI_BLOCK_IO_MEDIA characteristics set in VirtioBlkInit().
Should they do nonetheless, we do nothing, successfully.
**/
EFI_STATUS
EFIAPI
VirtioBlkFlushBlocks (
IN EFI_BLOCK_IO_PROTOCOL *This
);
//
// The purpose of the following scaffolding (EFI_COMPONENT_NAME_PROTOCOL and
// EFI_COMPONENT_NAME2_PROTOCOL implementation) is to format the driver's name
// in English, for display on standard console devices. This is recommended for
// UEFI drivers that follow the UEFI Driver Model. Refer to the Driver Writer's
// Guide for UEFI 2.3.1 v1.01, 11 UEFI Driver and Controller Names.
//
// Device type names ("Virtio Block Device") are not formatted because the
// driver supports only that device type. Therefore the driver name suffices
// for unambiguous identification.
//
EFI_STATUS
EFIAPI
VirtioBlkGetDriverName (
IN EFI_COMPONENT_NAME_PROTOCOL *This,
IN CHAR8 *Language,
OUT CHAR16 **DriverName
);
EFI_STATUS
EFIAPI
VirtioBlkGetDeviceName (
IN EFI_COMPONENT_NAME_PROTOCOL *This,
IN EFI_HANDLE DeviceHandle,
IN EFI_HANDLE ChildHandle,
IN CHAR8 *Language,
OUT CHAR16 **ControllerName
);
#endif // _VIRTIO_BLK_DXE_H_