3 This is a simple fault tolerant write driver that is intended to use in the SMM environment.
5 This boot service protocol only provides fault tolerant write capability for
6 block devices. The protocol has internal non-volatile intermediate storage
7 of the data and private information. It should be able to recover
8 automatically from a critical fault, such as power failure.
10 The implementation uses an FTW (Fault Tolerant Write) Work Space.
11 This work space is a memory copy of the work space on the Working Block,
12 the size of the work space is the FTW_WORK_SPACE_SIZE bytes.
14 The work space stores each write record as EFI_FTW_RECORD structure.
15 The spare block stores the write buffer before write to the target block.
17 The write record has three states to specify the different phase of write operation.
18 1) WRITE_ALLOCATED is that the record is allocated in write space.
19 The information of write operation is stored in write record structure.
20 2) SPARE_COMPLETED is that the data from write buffer is writed into the spare block as the backup.
21 3) WRITE_COMPLETED is that the data is copied from the spare block to the target block.
23 This driver operates the data as the whole size of spare block.
24 It first read the SpareAreaLength data from the target block into the spare memory buffer.
25 Then copy the write buffer data into the spare memory buffer.
26 Then write the spare memory buffer into the spare block.
27 Final copy the data from the spare block to the target block.
29 To make this drive work well, the following conditions must be satisfied:
30 1. The write NumBytes data must be fit within Spare area.
31 Offset + NumBytes <= SpareAreaLength
32 2. The whole flash range has the same block size.
33 3. Working block is an area which contains working space in its last block and has the same size as spare block.
34 4. Working Block area must be in the single one Firmware Volume Block range which FVB protocol is produced on.
35 5. Spare area must be in the single one Firmware Volume Block range which FVB protocol is produced on.
36 6. Any write data area (SpareAreaLength Area) which the data will be written into must be
37 in the single one Firmware Volume Block range which FVB protocol is produced on.
38 7. If write data area (such as Variable range) is enlarged, the spare area range must be enlarged.
39 The spare area must be enough large to store the write data before write them into the target range.
40 If one of them is not satisfied, FtwWrite may fail.
41 Usually, Spare area only takes one block. That's SpareAreaLength = BlockSize, NumberOfSpareBlock = 1.
43 Caution: This module requires additional review when modified.
44 This driver need to make sure the CommBuffer is not in the SMRAM range.
46 Copyright (c) 2010 - 2013, Intel Corporation. All rights reserved.<BR>
47 This program and the accompanying materials
48 are licensed and made available under the terms and conditions of the BSD License
49 which accompanies this distribution. The full text of the license may be found at
50 http://opensource.org/licenses/bsd-license.php
52 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
53 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
58 #include <Library/SmmServicesTableLib.h>
59 #include <Protocol/SmmSwapAddressRange.h>
60 #include "FaultTolerantWrite.h"
61 #include "FaultTolerantWriteSmmCommon.h"
62 #include <Protocol/SmmAccess2.h>
63 #include <Protocol/SmmEndOfDxe.h>
65 EFI_EVENT mFvbRegistration
= NULL
;
66 EFI_FTW_DEVICE
*mFtwDevice
= NULL
;
67 EFI_SMRAM_DESCRIPTOR
*mSmramRanges
;
68 UINTN mSmramRangeCount
;
71 /// The flag to indicate whether the platform has left the DXE phase of execution.
73 BOOLEAN mEndOfDxe
= FALSE
;
76 This function check if the address is in SMRAM.
78 @param Buffer the buffer address to be checked.
79 @param Length the buffer length to be checked.
81 @retval TRUE this address is in SMRAM.
82 @retval FALSE this address is NOT in SMRAM.
85 InternalIsAddressInSmram (
86 IN EFI_PHYSICAL_ADDRESS Buffer
,
92 for (Index
= 0; Index
< mSmramRangeCount
; Index
++) {
93 if (((Buffer
>= mSmramRanges
[Index
].CpuStart
) && (Buffer
< mSmramRanges
[Index
].CpuStart
+ mSmramRanges
[Index
].PhysicalSize
)) ||
94 ((mSmramRanges
[Index
].CpuStart
>= Buffer
) && (mSmramRanges
[Index
].CpuStart
< Buffer
+ Length
))) {
103 This function check if the address refered by Buffer and Length is valid.
105 @param Buffer the buffer address to be checked.
106 @param Length the buffer length to be checked.
108 @retval TRUE this address is valid.
109 @retval FALSE this address is NOT valid.
112 InternalIsAddressValid (
117 if (Buffer
> (MAX_ADDRESS
- Length
)) {
123 if (InternalIsAddressInSmram ((EFI_PHYSICAL_ADDRESS
)Buffer
, (UINT64
)Length
)) {
130 Retrive the SMM FVB protocol interface by HANDLE.
132 @param[in] FvBlockHandle The handle of SMM FVB protocol that provides services for
133 reading, writing, and erasing the target block.
134 @param[out] FvBlock The interface of SMM FVB protocol
136 @retval EFI_SUCCESS The interface information for the specified protocol was returned.
137 @retval EFI_UNSUPPORTED The device does not support the SMM FVB protocol.
138 @retval EFI_INVALID_PARAMETER FvBlockHandle is not a valid EFI_HANDLE or FvBlock is NULL.
143 IN EFI_HANDLE FvBlockHandle
,
144 OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL
**FvBlock
148 // To get the SMM FVB protocol interface on the handle
150 return gSmst
->SmmHandleProtocol (
152 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
158 Retrive the SMM Swap Address Range protocol interface.
160 @param[out] SarProtocol The interface of SMM SAR protocol
162 @retval EFI_SUCCESS The SMM SAR protocol instance was found and returned in SarProtocol.
163 @retval EFI_NOT_FOUND The SMM SAR protocol instance was not found.
164 @retval EFI_INVALID_PARAMETER SarProtocol is NULL.
169 OUT VOID
**SarProtocol
175 // Locate Smm Swap Address Range protocol
177 Status
= gSmst
->SmmLocateProtocol (
178 &gEfiSmmSwapAddressRangeProtocolGuid
,
186 Function returns an array of handles that support the SMM FVB protocol
187 in a buffer allocated from pool.
189 @param[out] NumberHandles The number of handles returned in Buffer.
190 @param[out] Buffer A pointer to the buffer to return the requested
191 array of handles that support SMM FVB protocol.
193 @retval EFI_SUCCESS The array of handles was returned in Buffer, and the number of
194 handles in Buffer was returned in NumberHandles.
195 @retval EFI_NOT_FOUND No SMM FVB handle was found.
196 @retval EFI_OUT_OF_RESOURCES There is not enough pool memory to store the matching results.
197 @retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
201 GetFvbCountAndBuffer (
202 OUT UINTN
*NumberHandles
,
203 OUT EFI_HANDLE
**Buffer
209 if ((NumberHandles
== NULL
) || (Buffer
== NULL
)) {
210 return EFI_INVALID_PARAMETER
;
216 Status
= gSmst
->SmmLocateHandle (
218 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
223 if (EFI_ERROR(Status
) && Status
!= EFI_BUFFER_TOO_SMALL
) {
224 return EFI_NOT_FOUND
;
227 *Buffer
= AllocatePool (BufferSize
);
228 if (*Buffer
== NULL
) {
229 return EFI_OUT_OF_RESOURCES
;
232 Status
= gSmst
->SmmLocateHandle (
234 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
240 *NumberHandles
= BufferSize
/ sizeof(EFI_HANDLE
);
241 if (EFI_ERROR(Status
)) {
252 Get the handle of the SMM FVB protocol by the FVB base address and attributes.
254 @param[in] Address The base address of SMM FVB protocol.
255 @param[in] Attributes The attributes of the SMM FVB protocol.
256 @param[out] SmmFvbHandle The handle of the SMM FVB protocol.
258 @retval EFI_SUCCESS The FVB handle is found.
259 @retval EFI_ABORTED The FVB protocol is not found.
263 GetFvbByAddressAndAttribute (
264 IN EFI_PHYSICAL_ADDRESS Address
,
265 IN EFI_FVB_ATTRIBUTES_2 Attributes
,
266 OUT EFI_HANDLE
*SmmFvbHandle
270 EFI_HANDLE
*HandleBuffer
;
273 EFI_PHYSICAL_ADDRESS FvbBaseAddress
;
274 EFI_FVB_ATTRIBUTES_2 FvbAttributes
;
275 EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL
*Fvb
;
278 // Locate all handles of SMM Fvb protocol.
280 Status
= GetFvbCountAndBuffer (&HandleCount
, &HandleBuffer
);
281 if (EFI_ERROR (Status
)) {
286 // Find the proper SMM Fvb handle by the address and attributes.
288 for (Index
= 0; Index
< HandleCount
; Index
++) {
289 Status
= FtwGetFvbByHandle (HandleBuffer
[Index
], &Fvb
);
290 if (EFI_ERROR (Status
)) {
294 // Compare the address.
296 Status
= Fvb
->GetPhysicalAddress (Fvb
, &FvbBaseAddress
);
297 if (EFI_ERROR (Status
)) {
300 if (Address
!= FvbBaseAddress
) {
305 // Compare the attribute.
307 Status
= Fvb
->GetAttributes (Fvb
, &FvbAttributes
);
308 if (EFI_ERROR (Status
)) {
311 if (Attributes
!= FvbAttributes
) {
316 // Found the proper FVB handle.
318 *SmmFvbHandle
= HandleBuffer
[Index
];
319 FreePool (HandleBuffer
);
323 FreePool (HandleBuffer
);
328 Communication service SMI Handler entry.
330 This SMI handler provides services for the fault tolerant write wrapper driver.
332 Caution: This function requires additional review when modified.
333 This driver need to make sure the CommBuffer is not in the SMRAM range.
334 Also in FTW_FUNCTION_GET_LAST_WRITE case, check SmmFtwGetLastWriteHeader->Data +
335 SmmFtwGetLastWriteHeader->PrivateDataSize within communication buffer.
337 @param[in] DispatchHandle The unique handle assigned to this handler by SmiHandlerRegister().
338 @param[in] RegisterContext Points to an optional handler context which was specified when the
339 handler was registered.
340 @param[in, out] CommBuffer A pointer to a collection of data in memory that will be conveyed
341 from a non-SMM environment into an SMM environment.
342 @param[in, out] CommBufferSize The size of the CommBuffer.
344 @retval EFI_SUCCESS The interrupt was handled and quiesced. No other handlers
345 should still be called.
346 @retval EFI_WARN_INTERRUPT_SOURCE_QUIESCED The interrupt has been quiesced but other handlers should
348 @retval EFI_WARN_INTERRUPT_SOURCE_PENDING The interrupt is still pending and other handlers should still
350 @retval EFI_INTERRUPT_PENDING The interrupt could not be quiesced.
355 SmmFaultTolerantWriteHandler (
356 IN EFI_HANDLE DispatchHandle
,
357 IN CONST VOID
*RegisterContext
,
358 IN OUT VOID
*CommBuffer
,
359 IN OUT UINTN
*CommBufferSize
363 SMM_FTW_COMMUNICATE_FUNCTION_HEADER
*SmmFtwFunctionHeader
;
364 SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
*SmmGetMaxBlockSizeHeader
;
365 SMM_FTW_ALLOCATE_HEADER
*SmmFtwAllocateHeader
;
366 SMM_FTW_WRITE_HEADER
*SmmFtwWriteHeader
;
367 SMM_FTW_RESTART_HEADER
*SmmFtwRestartHeader
;
368 SMM_FTW_GET_LAST_WRITE_HEADER
*SmmFtwGetLastWriteHeader
;
370 EFI_HANDLE SmmFvbHandle
;
372 UINTN CommBufferPayloadSize
;
373 UINTN PrivateDataSize
;
378 // If input is invalid, stop processing this SMI
380 if (CommBuffer
== NULL
|| CommBufferSize
== NULL
) {
384 if (*CommBufferSize
< SMM_FTW_COMMUNICATE_HEADER_SIZE
) {
385 DEBUG ((EFI_D_ERROR
, "SmmFtwHandler: SMM communication buffer size invalid!\n"));
388 CommBufferPayloadSize
= *CommBufferSize
- SMM_FTW_COMMUNICATE_HEADER_SIZE
;
390 if (!InternalIsAddressValid ((UINTN
)CommBuffer
, *CommBufferSize
)) {
391 DEBUG ((EFI_D_ERROR
, "SmmFtwHandler: SMM communication buffer in SMRAM or overflow!\n"));
395 SmmFtwFunctionHeader
= (SMM_FTW_COMMUNICATE_FUNCTION_HEADER
*)CommBuffer
;
399 // It will be not safe to expose the operations after End Of Dxe.
401 DEBUG ((EFI_D_ERROR
, "SmmFtwHandler: Not safe to do the operation: %x after End Of Dxe, so access denied!\n", SmmFtwFunctionHeader
->Function
));
402 SmmFtwFunctionHeader
->ReturnStatus
= EFI_ACCESS_DENIED
;
406 switch (SmmFtwFunctionHeader
->Function
) {
407 case FTW_FUNCTION_GET_MAX_BLOCK_SIZE
:
408 if (CommBufferPayloadSize
< sizeof (SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
)) {
409 DEBUG ((EFI_D_ERROR
, "GetMaxBlockSize: SMM communication buffer size invalid!\n"));
412 SmmGetMaxBlockSizeHeader
= (SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
*) SmmFtwFunctionHeader
->Data
;
414 Status
= FtwGetMaxBlockSize (
415 &mFtwDevice
->FtwInstance
,
416 &SmmGetMaxBlockSizeHeader
->BlockSize
420 case FTW_FUNCTION_ALLOCATE
:
421 if (CommBufferPayloadSize
< sizeof (SMM_FTW_ALLOCATE_HEADER
)) {
422 DEBUG ((EFI_D_ERROR
, "Allocate: SMM communication buffer size invalid!\n"));
425 SmmFtwAllocateHeader
= (SMM_FTW_ALLOCATE_HEADER
*) SmmFtwFunctionHeader
->Data
;
426 Status
= FtwAllocate (
427 &mFtwDevice
->FtwInstance
,
428 &SmmFtwAllocateHeader
->CallerId
,
429 SmmFtwAllocateHeader
->PrivateDataSize
,
430 SmmFtwAllocateHeader
->NumberOfWrites
434 case FTW_FUNCTION_WRITE
:
435 if (CommBufferPayloadSize
< OFFSET_OF (SMM_FTW_WRITE_HEADER
, Data
)) {
436 DEBUG ((EFI_D_ERROR
, "Write: SMM communication buffer size invalid!\n"));
439 SmmFtwWriteHeader
= (SMM_FTW_WRITE_HEADER
*) SmmFtwFunctionHeader
->Data
;
440 Length
= SmmFtwWriteHeader
->Length
;
441 PrivateDataSize
= SmmFtwWriteHeader
->PrivateDataSize
;
442 if (((UINTN
)(~0) - Length
< OFFSET_OF (SMM_FTW_WRITE_HEADER
, Data
)) ||
443 ((UINTN
)(~0) - PrivateDataSize
< OFFSET_OF (SMM_FTW_WRITE_HEADER
, Data
) + Length
)) {
445 // Prevent InfoSize overflow
447 Status
= EFI_ACCESS_DENIED
;
450 InfoSize
= OFFSET_OF (SMM_FTW_WRITE_HEADER
, Data
) + Length
+ PrivateDataSize
;
453 // SMRAM range check already covered before
455 if (InfoSize
> CommBufferPayloadSize
) {
456 DEBUG ((EFI_D_ERROR
, "Write: Data size exceed communication buffer size limit!\n"));
457 Status
= EFI_ACCESS_DENIED
;
461 if (PrivateDataSize
== 0) {
464 PrivateData
= (VOID
*)&SmmFtwWriteHeader
->Data
[Length
];
466 Status
= GetFvbByAddressAndAttribute (
467 SmmFtwWriteHeader
->FvbBaseAddress
,
468 SmmFtwWriteHeader
->FvbAttributes
,
471 if (!EFI_ERROR (Status
)) {
473 &mFtwDevice
->FtwInstance
,
474 SmmFtwWriteHeader
->Lba
,
475 SmmFtwWriteHeader
->Offset
,
479 SmmFtwWriteHeader
->Data
484 case FTW_FUNCTION_RESTART
:
485 if (CommBufferPayloadSize
< sizeof (SMM_FTW_RESTART_HEADER
)) {
486 DEBUG ((EFI_D_ERROR
, "Restart: SMM communication buffer size invalid!\n"));
489 SmmFtwRestartHeader
= (SMM_FTW_RESTART_HEADER
*) SmmFtwFunctionHeader
->Data
;
490 Status
= GetFvbByAddressAndAttribute (
491 SmmFtwRestartHeader
->FvbBaseAddress
,
492 SmmFtwRestartHeader
->FvbAttributes
,
495 if (!EFI_ERROR (Status
)) {
496 Status
= FtwRestart (&mFtwDevice
->FtwInstance
, SmmFvbHandle
);
500 case FTW_FUNCTION_ABORT
:
501 Status
= FtwAbort (&mFtwDevice
->FtwInstance
);
504 case FTW_FUNCTION_GET_LAST_WRITE
:
505 if (CommBufferPayloadSize
< OFFSET_OF (SMM_FTW_GET_LAST_WRITE_HEADER
, Data
)) {
506 DEBUG ((EFI_D_ERROR
, "GetLastWrite: SMM communication buffer size invalid!\n"));
509 SmmFtwGetLastWriteHeader
= (SMM_FTW_GET_LAST_WRITE_HEADER
*) SmmFtwFunctionHeader
->Data
;
510 PrivateDataSize
= SmmFtwGetLastWriteHeader
->PrivateDataSize
;
511 if ((UINTN
)(~0) - PrivateDataSize
< OFFSET_OF (SMM_FTW_GET_LAST_WRITE_HEADER
, Data
)){
513 // Prevent InfoSize overflow
515 Status
= EFI_ACCESS_DENIED
;
518 InfoSize
= OFFSET_OF (SMM_FTW_GET_LAST_WRITE_HEADER
, Data
) + PrivateDataSize
;
521 // SMRAM range check already covered before
523 if (InfoSize
> CommBufferPayloadSize
) {
524 DEBUG ((EFI_D_ERROR
, "Data size exceed communication buffer size limit!\n"));
525 Status
= EFI_ACCESS_DENIED
;
529 Status
= FtwGetLastWrite (
530 &mFtwDevice
->FtwInstance
,
531 &SmmFtwGetLastWriteHeader
->CallerId
,
532 &SmmFtwGetLastWriteHeader
->Lba
,
533 &SmmFtwGetLastWriteHeader
->Offset
,
534 &SmmFtwGetLastWriteHeader
->Length
,
536 (VOID
*)SmmFtwGetLastWriteHeader
->Data
,
537 &SmmFtwGetLastWriteHeader
->Complete
539 SmmFtwGetLastWriteHeader
->PrivateDataSize
= PrivateDataSize
;
543 Status
= EFI_UNSUPPORTED
;
546 SmmFtwFunctionHeader
->ReturnStatus
= Status
;
553 SMM Firmware Volume Block Protocol notification event handler.
555 @param[in] Protocol Points to the protocol's unique identifier
556 @param[in] Interface Points to the interface instance
557 @param[in] Handle The handle on which the interface was installed
559 @retval EFI_SUCCESS SmmEventCallback runs successfully
564 FvbNotificationEvent (
565 IN CONST EFI_GUID
*Protocol
,
571 EFI_SMM_FAULT_TOLERANT_WRITE_PROTOCOL
*FtwProtocol
;
572 EFI_HANDLE SmmFtwHandle
;
573 EFI_HANDLE FtwHandle
;
576 // Just return to avoid install SMM FaultTolerantWriteProtocol again
577 // if SMM Fault Tolerant Write protocol had been installed.
579 Status
= gSmst
->SmmLocateProtocol (
580 &gEfiSmmFaultTolerantWriteProtocolGuid
,
582 (VOID
**) &FtwProtocol
584 if (!EFI_ERROR (Status
)) {
589 // Found proper FVB protocol and initialize FtwDevice for protocol installation
591 Status
= InitFtwProtocol (mFtwDevice
);
592 if (EFI_ERROR(Status
)) {
597 // Install protocol interface
599 Status
= gSmst
->SmmInstallProtocolInterface (
601 &gEfiSmmFaultTolerantWriteProtocolGuid
,
602 EFI_NATIVE_INTERFACE
,
603 &mFtwDevice
->FtwInstance
605 ASSERT_EFI_ERROR (Status
);
608 /// Register SMM FTW SMI handler
610 Status
= gSmst
->SmiHandlerRegister (SmmFaultTolerantWriteHandler
, &gEfiSmmFaultTolerantWriteProtocolGuid
, &SmmFtwHandle
);
611 ASSERT_EFI_ERROR (Status
);
614 // Notify the Ftw wrapper driver SMM Ftw is ready
617 Status
= gBS
->InstallProtocolInterface (
619 &gEfiSmmFaultTolerantWriteProtocolGuid
,
620 EFI_NATIVE_INTERFACE
,
623 ASSERT_EFI_ERROR (Status
);
629 SMM END_OF_DXE protocol notification event handler.
631 @param Protocol Points to the protocol's unique identifier
632 @param Interface Points to the interface instance
633 @param Handle The handle on which the interface was installed
635 @retval EFI_SUCCESS SmmEndOfDxeCallback runs successfully
640 SmmEndOfDxeCallback (
641 IN CONST EFI_GUID
*Protocol
,
651 This function is the entry point of the Fault Tolerant Write driver.
653 @param[in] ImageHandle A handle for the image that is initializing this driver
654 @param[in] SystemTable A pointer to the EFI system table
656 @retval EFI_SUCCESS The initialization finished successfully.
657 @retval EFI_OUT_OF_RESOURCES Allocate memory error
658 @retval EFI_INVALID_PARAMETER Workspace or Spare block does not exist
663 SmmFaultTolerantWriteInitialize (
664 IN EFI_HANDLE ImageHandle
,
665 IN EFI_SYSTEM_TABLE
*SystemTable
669 EFI_SMM_ACCESS2_PROTOCOL
*SmmAccess
;
671 VOID
*SmmEndOfDxeRegistration
;
674 // Allocate private data structure for SMM FTW protocol and do some initialization
676 Status
= InitFtwDevice (&mFtwDevice
);
677 if (EFI_ERROR(Status
)) {
682 // Get SMRAM information
684 Status
= gBS
->LocateProtocol (&gEfiSmmAccess2ProtocolGuid
, NULL
, (VOID
**)&SmmAccess
);
685 ASSERT_EFI_ERROR (Status
);
688 Status
= SmmAccess
->GetCapabilities (SmmAccess
, &Size
, NULL
);
689 ASSERT (Status
== EFI_BUFFER_TOO_SMALL
);
691 Status
= gSmst
->SmmAllocatePool (
692 EfiRuntimeServicesData
,
694 (VOID
**)&mSmramRanges
696 ASSERT_EFI_ERROR (Status
);
698 Status
= SmmAccess
->GetCapabilities (SmmAccess
, &Size
, mSmramRanges
);
699 ASSERT_EFI_ERROR (Status
);
701 mSmramRangeCount
= Size
/ sizeof (EFI_SMRAM_DESCRIPTOR
);
704 // Register EFI_SMM_END_OF_DXE_PROTOCOL_GUID notify function.
706 Status
= gSmst
->SmmRegisterProtocolNotify (
707 &gEfiSmmEndOfDxeProtocolGuid
,
709 &SmmEndOfDxeRegistration
711 ASSERT_EFI_ERROR (Status
);
714 // Register FvbNotificationEvent () notify function.
716 Status
= gSmst
->SmmRegisterProtocolNotify (
717 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
718 FvbNotificationEvent
,
721 ASSERT_EFI_ERROR (Status
);
723 FvbNotificationEvent (NULL
, NULL
, NULL
);