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 - 2015, 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 <Library/SmmMemLib.h>
60 #include <Protocol/SmmSwapAddressRange.h>
61 #include "FaultTolerantWrite.h"
62 #include "FaultTolerantWriteSmmCommon.h"
63 #include <Protocol/SmmEndOfDxe.h>
65 EFI_EVENT mFvbRegistration
= NULL
;
66 EFI_FTW_DEVICE
*mFtwDevice
= NULL
;
69 /// The flag to indicate whether the platform has left the DXE phase of execution.
71 BOOLEAN mEndOfDxe
= FALSE
;
74 Retrieve the SMM FVB protocol interface by HANDLE.
76 @param[in] FvBlockHandle The handle of SMM FVB protocol that provides services for
77 reading, writing, and erasing the target block.
78 @param[out] FvBlock The interface of SMM FVB protocol
80 @retval EFI_SUCCESS The interface information for the specified protocol was returned.
81 @retval EFI_UNSUPPORTED The device does not support the SMM FVB protocol.
82 @retval EFI_INVALID_PARAMETER FvBlockHandle is not a valid EFI_HANDLE or FvBlock is NULL.
87 IN EFI_HANDLE FvBlockHandle
,
88 OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL
**FvBlock
92 // To get the SMM FVB protocol interface on the handle
94 return gSmst
->SmmHandleProtocol (
96 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
102 Retrieve the SMM Swap Address Range protocol interface.
104 @param[out] SarProtocol The interface of SMM SAR protocol
106 @retval EFI_SUCCESS The SMM SAR protocol instance was found and returned in SarProtocol.
107 @retval EFI_NOT_FOUND The SMM SAR protocol instance was not found.
108 @retval EFI_INVALID_PARAMETER SarProtocol is NULL.
113 OUT VOID
**SarProtocol
119 // Locate Smm Swap Address Range protocol
121 Status
= gSmst
->SmmLocateProtocol (
122 &gEfiSmmSwapAddressRangeProtocolGuid
,
130 Function returns an array of handles that support the SMM FVB protocol
131 in a buffer allocated from pool.
133 @param[out] NumberHandles The number of handles returned in Buffer.
134 @param[out] Buffer A pointer to the buffer to return the requested
135 array of handles that support SMM FVB protocol.
137 @retval EFI_SUCCESS The array of handles was returned in Buffer, and the number of
138 handles in Buffer was returned in NumberHandles.
139 @retval EFI_NOT_FOUND No SMM FVB handle was found.
140 @retval EFI_OUT_OF_RESOURCES There is not enough pool memory to store the matching results.
141 @retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
145 GetFvbCountAndBuffer (
146 OUT UINTN
*NumberHandles
,
147 OUT EFI_HANDLE
**Buffer
153 if ((NumberHandles
== NULL
) || (Buffer
== NULL
)) {
154 return EFI_INVALID_PARAMETER
;
160 Status
= gSmst
->SmmLocateHandle (
162 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
167 if (EFI_ERROR(Status
) && Status
!= EFI_BUFFER_TOO_SMALL
) {
168 return EFI_NOT_FOUND
;
171 *Buffer
= AllocatePool (BufferSize
);
172 if (*Buffer
== NULL
) {
173 return EFI_OUT_OF_RESOURCES
;
176 Status
= gSmst
->SmmLocateHandle (
178 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
184 *NumberHandles
= BufferSize
/ sizeof(EFI_HANDLE
);
185 if (EFI_ERROR(Status
)) {
196 Get the handle of the SMM FVB protocol by the FVB base address and attributes.
198 @param[in] Address The base address of SMM FVB protocol.
199 @param[in] Attributes The attributes of the SMM FVB protocol.
200 @param[out] SmmFvbHandle The handle of the SMM FVB protocol.
202 @retval EFI_SUCCESS The FVB handle is found.
203 @retval EFI_ABORTED The FVB protocol is not found.
207 GetFvbByAddressAndAttribute (
208 IN EFI_PHYSICAL_ADDRESS Address
,
209 IN EFI_FVB_ATTRIBUTES_2 Attributes
,
210 OUT EFI_HANDLE
*SmmFvbHandle
214 EFI_HANDLE
*HandleBuffer
;
217 EFI_PHYSICAL_ADDRESS FvbBaseAddress
;
218 EFI_FVB_ATTRIBUTES_2 FvbAttributes
;
219 EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL
*Fvb
;
224 // Locate all handles of SMM Fvb protocol.
226 Status
= GetFvbCountAndBuffer (&HandleCount
, &HandleBuffer
);
227 if (EFI_ERROR (Status
)) {
232 // Find the proper SMM Fvb handle by the address and attributes.
234 for (Index
= 0; Index
< HandleCount
; Index
++) {
235 Status
= FtwGetFvbByHandle (HandleBuffer
[Index
], &Fvb
);
236 if (EFI_ERROR (Status
)) {
240 // Compare the address.
242 Status
= Fvb
->GetPhysicalAddress (Fvb
, &FvbBaseAddress
);
243 if (EFI_ERROR (Status
)) {
246 if (Address
!= FvbBaseAddress
) {
251 // Compare the attribute.
253 Status
= Fvb
->GetAttributes (Fvb
, &FvbAttributes
);
254 if (EFI_ERROR (Status
)) {
257 if (Attributes
!= FvbAttributes
) {
262 // Found the proper FVB handle.
264 *SmmFvbHandle
= HandleBuffer
[Index
];
265 FreePool (HandleBuffer
);
269 FreePool (HandleBuffer
);
274 Communication service SMI Handler entry.
276 This SMI handler provides services for the fault tolerant write wrapper driver.
278 Caution: This function requires additional review when modified.
279 This driver need to make sure the CommBuffer is not in the SMRAM range.
280 Also in FTW_FUNCTION_GET_LAST_WRITE case, check SmmFtwGetLastWriteHeader->Data +
281 SmmFtwGetLastWriteHeader->PrivateDataSize within communication buffer.
283 @param[in] DispatchHandle The unique handle assigned to this handler by SmiHandlerRegister().
284 @param[in] RegisterContext Points to an optional handler context which was specified when the
285 handler was registered.
286 @param[in, out] CommBuffer A pointer to a collection of data in memory that will be conveyed
287 from a non-SMM environment into an SMM environment.
288 @param[in, out] CommBufferSize The size of the CommBuffer.
290 @retval EFI_SUCCESS The interrupt was handled and quiesced. No other handlers
291 should still be called.
292 @retval EFI_WARN_INTERRUPT_SOURCE_QUIESCED The interrupt has been quiesced but other handlers should
294 @retval EFI_WARN_INTERRUPT_SOURCE_PENDING The interrupt is still pending and other handlers should still
296 @retval EFI_INTERRUPT_PENDING The interrupt could not be quiesced.
301 SmmFaultTolerantWriteHandler (
302 IN EFI_HANDLE DispatchHandle
,
303 IN CONST VOID
*RegisterContext
,
304 IN OUT VOID
*CommBuffer
,
305 IN OUT UINTN
*CommBufferSize
309 SMM_FTW_COMMUNICATE_FUNCTION_HEADER
*SmmFtwFunctionHeader
;
310 SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
*SmmGetMaxBlockSizeHeader
;
311 SMM_FTW_ALLOCATE_HEADER
*SmmFtwAllocateHeader
;
312 SMM_FTW_WRITE_HEADER
*SmmFtwWriteHeader
;
313 SMM_FTW_RESTART_HEADER
*SmmFtwRestartHeader
;
314 SMM_FTW_GET_LAST_WRITE_HEADER
*SmmFtwGetLastWriteHeader
;
316 EFI_HANDLE SmmFvbHandle
;
318 UINTN CommBufferPayloadSize
;
319 UINTN PrivateDataSize
;
321 UINTN TempCommBufferSize
;
324 // If input is invalid, stop processing this SMI
326 if (CommBuffer
== NULL
|| CommBufferSize
== NULL
) {
330 TempCommBufferSize
= *CommBufferSize
;
332 if (TempCommBufferSize
< SMM_FTW_COMMUNICATE_HEADER_SIZE
) {
333 DEBUG ((EFI_D_ERROR
, "SmmFtwHandler: SMM communication buffer size invalid!\n"));
336 CommBufferPayloadSize
= TempCommBufferSize
- SMM_FTW_COMMUNICATE_HEADER_SIZE
;
338 if (!SmmIsBufferOutsideSmmValid ((UINTN
)CommBuffer
, TempCommBufferSize
)) {
339 DEBUG ((EFI_D_ERROR
, "SmmFtwHandler: SMM communication buffer in SMRAM or overflow!\n"));
343 SmmFtwFunctionHeader
= (SMM_FTW_COMMUNICATE_FUNCTION_HEADER
*)CommBuffer
;
347 // It will be not safe to expose the operations after End Of Dxe.
349 DEBUG ((EFI_D_ERROR
, "SmmFtwHandler: Not safe to do the operation: %x after End Of Dxe, so access denied!\n", SmmFtwFunctionHeader
->Function
));
350 SmmFtwFunctionHeader
->ReturnStatus
= EFI_ACCESS_DENIED
;
354 switch (SmmFtwFunctionHeader
->Function
) {
355 case FTW_FUNCTION_GET_MAX_BLOCK_SIZE
:
356 if (CommBufferPayloadSize
< sizeof (SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
)) {
357 DEBUG ((EFI_D_ERROR
, "GetMaxBlockSize: SMM communication buffer size invalid!\n"));
360 SmmGetMaxBlockSizeHeader
= (SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
*) SmmFtwFunctionHeader
->Data
;
362 Status
= FtwGetMaxBlockSize (
363 &mFtwDevice
->FtwInstance
,
364 &SmmGetMaxBlockSizeHeader
->BlockSize
368 case FTW_FUNCTION_ALLOCATE
:
369 if (CommBufferPayloadSize
< sizeof (SMM_FTW_ALLOCATE_HEADER
)) {
370 DEBUG ((EFI_D_ERROR
, "Allocate: SMM communication buffer size invalid!\n"));
373 SmmFtwAllocateHeader
= (SMM_FTW_ALLOCATE_HEADER
*) SmmFtwFunctionHeader
->Data
;
374 Status
= FtwAllocate (
375 &mFtwDevice
->FtwInstance
,
376 &SmmFtwAllocateHeader
->CallerId
,
377 SmmFtwAllocateHeader
->PrivateDataSize
,
378 SmmFtwAllocateHeader
->NumberOfWrites
382 case FTW_FUNCTION_WRITE
:
383 if (CommBufferPayloadSize
< OFFSET_OF (SMM_FTW_WRITE_HEADER
, Data
)) {
384 DEBUG ((EFI_D_ERROR
, "Write: SMM communication buffer size invalid!\n"));
387 SmmFtwWriteHeader
= (SMM_FTW_WRITE_HEADER
*) SmmFtwFunctionHeader
->Data
;
388 Length
= SmmFtwWriteHeader
->Length
;
389 PrivateDataSize
= SmmFtwWriteHeader
->PrivateDataSize
;
390 if (((UINTN
)(~0) - Length
< OFFSET_OF (SMM_FTW_WRITE_HEADER
, Data
)) ||
391 ((UINTN
)(~0) - PrivateDataSize
< OFFSET_OF (SMM_FTW_WRITE_HEADER
, Data
) + Length
)) {
393 // Prevent InfoSize overflow
395 Status
= EFI_ACCESS_DENIED
;
398 InfoSize
= OFFSET_OF (SMM_FTW_WRITE_HEADER
, Data
) + Length
+ PrivateDataSize
;
401 // SMRAM range check already covered before
403 if (InfoSize
> CommBufferPayloadSize
) {
404 DEBUG ((EFI_D_ERROR
, "Write: Data size exceed communication buffer size limit!\n"));
405 Status
= EFI_ACCESS_DENIED
;
409 if (PrivateDataSize
== 0) {
412 PrivateData
= (VOID
*)&SmmFtwWriteHeader
->Data
[Length
];
414 Status
= GetFvbByAddressAndAttribute (
415 SmmFtwWriteHeader
->FvbBaseAddress
,
416 SmmFtwWriteHeader
->FvbAttributes
,
419 if (!EFI_ERROR (Status
)) {
421 &mFtwDevice
->FtwInstance
,
422 SmmFtwWriteHeader
->Lba
,
423 SmmFtwWriteHeader
->Offset
,
427 SmmFtwWriteHeader
->Data
432 case FTW_FUNCTION_RESTART
:
433 if (CommBufferPayloadSize
< sizeof (SMM_FTW_RESTART_HEADER
)) {
434 DEBUG ((EFI_D_ERROR
, "Restart: SMM communication buffer size invalid!\n"));
437 SmmFtwRestartHeader
= (SMM_FTW_RESTART_HEADER
*) SmmFtwFunctionHeader
->Data
;
438 Status
= GetFvbByAddressAndAttribute (
439 SmmFtwRestartHeader
->FvbBaseAddress
,
440 SmmFtwRestartHeader
->FvbAttributes
,
443 if (!EFI_ERROR (Status
)) {
444 Status
= FtwRestart (&mFtwDevice
->FtwInstance
, SmmFvbHandle
);
448 case FTW_FUNCTION_ABORT
:
449 Status
= FtwAbort (&mFtwDevice
->FtwInstance
);
452 case FTW_FUNCTION_GET_LAST_WRITE
:
453 if (CommBufferPayloadSize
< OFFSET_OF (SMM_FTW_GET_LAST_WRITE_HEADER
, Data
)) {
454 DEBUG ((EFI_D_ERROR
, "GetLastWrite: SMM communication buffer size invalid!\n"));
457 SmmFtwGetLastWriteHeader
= (SMM_FTW_GET_LAST_WRITE_HEADER
*) SmmFtwFunctionHeader
->Data
;
458 PrivateDataSize
= SmmFtwGetLastWriteHeader
->PrivateDataSize
;
459 if ((UINTN
)(~0) - PrivateDataSize
< OFFSET_OF (SMM_FTW_GET_LAST_WRITE_HEADER
, Data
)){
461 // Prevent InfoSize overflow
463 Status
= EFI_ACCESS_DENIED
;
466 InfoSize
= OFFSET_OF (SMM_FTW_GET_LAST_WRITE_HEADER
, Data
) + PrivateDataSize
;
469 // SMRAM range check already covered before
471 if (InfoSize
> CommBufferPayloadSize
) {
472 DEBUG ((EFI_D_ERROR
, "Data size exceed communication buffer size limit!\n"));
473 Status
= EFI_ACCESS_DENIED
;
477 Status
= FtwGetLastWrite (
478 &mFtwDevice
->FtwInstance
,
479 &SmmFtwGetLastWriteHeader
->CallerId
,
480 &SmmFtwGetLastWriteHeader
->Lba
,
481 &SmmFtwGetLastWriteHeader
->Offset
,
482 &SmmFtwGetLastWriteHeader
->Length
,
484 (VOID
*)SmmFtwGetLastWriteHeader
->Data
,
485 &SmmFtwGetLastWriteHeader
->Complete
487 SmmFtwGetLastWriteHeader
->PrivateDataSize
= PrivateDataSize
;
491 Status
= EFI_UNSUPPORTED
;
494 SmmFtwFunctionHeader
->ReturnStatus
= Status
;
501 SMM Firmware Volume Block Protocol notification event handler.
503 @param[in] Protocol Points to the protocol's unique identifier
504 @param[in] Interface Points to the interface instance
505 @param[in] Handle The handle on which the interface was installed
507 @retval EFI_SUCCESS SmmEventCallback runs successfully
512 FvbNotificationEvent (
513 IN CONST EFI_GUID
*Protocol
,
519 EFI_SMM_FAULT_TOLERANT_WRITE_PROTOCOL
*FtwProtocol
;
520 EFI_HANDLE SmmFtwHandle
;
521 EFI_HANDLE FtwHandle
;
524 // Just return to avoid install SMM FaultTolerantWriteProtocol again
525 // if SMM Fault Tolerant Write protocol had been installed.
527 Status
= gSmst
->SmmLocateProtocol (
528 &gEfiSmmFaultTolerantWriteProtocolGuid
,
530 (VOID
**) &FtwProtocol
532 if (!EFI_ERROR (Status
)) {
537 // Found proper FVB protocol and initialize FtwDevice for protocol installation
539 Status
= InitFtwProtocol (mFtwDevice
);
540 if (EFI_ERROR(Status
)) {
545 // Install protocol interface
547 Status
= gSmst
->SmmInstallProtocolInterface (
549 &gEfiSmmFaultTolerantWriteProtocolGuid
,
550 EFI_NATIVE_INTERFACE
,
551 &mFtwDevice
->FtwInstance
553 ASSERT_EFI_ERROR (Status
);
556 /// Register SMM FTW SMI handler
558 Status
= gSmst
->SmiHandlerRegister (SmmFaultTolerantWriteHandler
, &gEfiSmmFaultTolerantWriteProtocolGuid
, &SmmFtwHandle
);
559 ASSERT_EFI_ERROR (Status
);
562 // Notify the Ftw wrapper driver SMM Ftw is ready
565 Status
= gBS
->InstallProtocolInterface (
567 &gEfiSmmFaultTolerantWriteProtocolGuid
,
568 EFI_NATIVE_INTERFACE
,
571 ASSERT_EFI_ERROR (Status
);
577 SMM END_OF_DXE protocol notification event handler.
579 @param Protocol Points to the protocol's unique identifier
580 @param Interface Points to the interface instance
581 @param Handle The handle on which the interface was installed
583 @retval EFI_SUCCESS SmmEndOfDxeCallback runs successfully
588 SmmEndOfDxeCallback (
589 IN CONST EFI_GUID
*Protocol
,
599 This function is the entry point of the Fault Tolerant Write driver.
601 @param[in] ImageHandle A handle for the image that is initializing this driver
602 @param[in] SystemTable A pointer to the EFI system table
604 @retval EFI_SUCCESS The initialization finished successfully.
605 @retval EFI_OUT_OF_RESOURCES Allocate memory error
606 @retval EFI_INVALID_PARAMETER Workspace or Spare block does not exist
611 SmmFaultTolerantWriteInitialize (
612 IN EFI_HANDLE ImageHandle
,
613 IN EFI_SYSTEM_TABLE
*SystemTable
617 VOID
*SmmEndOfDxeRegistration
;
620 // Allocate private data structure for SMM FTW protocol and do some initialization
622 Status
= InitFtwDevice (&mFtwDevice
);
623 if (EFI_ERROR(Status
)) {
628 // Register EFI_SMM_END_OF_DXE_PROTOCOL_GUID notify function.
630 Status
= gSmst
->SmmRegisterProtocolNotify (
631 &gEfiSmmEndOfDxeProtocolGuid
,
633 &SmmEndOfDxeRegistration
635 ASSERT_EFI_ERROR (Status
);
638 // Register FvbNotificationEvent () notify function.
640 Status
= gSmst
->SmmRegisterProtocolNotify (
641 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
642 FvbNotificationEvent
,
645 ASSERT_EFI_ERROR (Status
);
647 FvbNotificationEvent (NULL
, NULL
, NULL
);