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
))) {
104 Retrive the SMM FVB protocol interface by HANDLE.
106 @param[in] FvBlockHandle The handle of SMM FVB protocol that provides services for
107 reading, writing, and erasing the target block.
108 @param[out] FvBlock The interface of SMM FVB protocol
110 @retval EFI_SUCCESS The interface information for the specified protocol was returned.
111 @retval EFI_UNSUPPORTED The device does not support the SMM FVB protocol.
112 @retval EFI_INVALID_PARAMETER FvBlockHandle is not a valid EFI_HANDLE or FvBlock is NULL.
117 IN EFI_HANDLE FvBlockHandle
,
118 OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL
**FvBlock
122 // To get the SMM FVB protocol interface on the handle
124 return gSmst
->SmmHandleProtocol (
126 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
132 Retrive the SMM Swap Address Range protocol interface.
134 @param[out] SarProtocol The interface of SMM SAR protocol
136 @retval EFI_SUCCESS The SMM SAR protocol instance was found and returned in SarProtocol.
137 @retval EFI_NOT_FOUND The SMM SAR protocol instance was not found.
138 @retval EFI_INVALID_PARAMETER SarProtocol is NULL.
143 OUT VOID
**SarProtocol
149 // Locate Smm Swap Address Range protocol
151 Status
= gSmst
->SmmLocateProtocol (
152 &gEfiSmmSwapAddressRangeProtocolGuid
,
160 Function returns an array of handles that support the SMM FVB protocol
161 in a buffer allocated from pool.
163 @param[out] NumberHandles The number of handles returned in Buffer.
164 @param[out] Buffer A pointer to the buffer to return the requested
165 array of handles that support SMM FVB protocol.
167 @retval EFI_SUCCESS The array of handles was returned in Buffer, and the number of
168 handles in Buffer was returned in NumberHandles.
169 @retval EFI_NOT_FOUND No SMM FVB handle was found.
170 @retval EFI_OUT_OF_RESOURCES There is not enough pool memory to store the matching results.
171 @retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
175 GetFvbCountAndBuffer (
176 OUT UINTN
*NumberHandles
,
177 OUT EFI_HANDLE
**Buffer
183 if ((NumberHandles
== NULL
) || (Buffer
== NULL
)) {
184 return EFI_INVALID_PARAMETER
;
190 Status
= gSmst
->SmmLocateHandle (
192 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
197 if (EFI_ERROR(Status
) && Status
!= EFI_BUFFER_TOO_SMALL
) {
198 return EFI_NOT_FOUND
;
201 *Buffer
= AllocatePool (BufferSize
);
202 if (*Buffer
== NULL
) {
203 return EFI_OUT_OF_RESOURCES
;
206 Status
= gSmst
->SmmLocateHandle (
208 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
214 *NumberHandles
= BufferSize
/ sizeof(EFI_HANDLE
);
215 if (EFI_ERROR(Status
)) {
226 Get the handle of the SMM FVB protocol by the FVB base address and attributes.
228 @param[in] Address The base address of SMM FVB protocol.
229 @param[in] Attributes The attributes of the SMM FVB protocol.
230 @param[out] SmmFvbHandle The handle of the SMM FVB protocol.
232 @retval EFI_SUCCESS The FVB handle is found.
233 @retval EFI_ABORTED The FVB protocol is not found.
237 GetFvbByAddressAndAttribute (
238 IN EFI_PHYSICAL_ADDRESS Address
,
239 IN EFI_FVB_ATTRIBUTES_2 Attributes
,
240 OUT EFI_HANDLE
*SmmFvbHandle
244 EFI_HANDLE
*HandleBuffer
;
247 EFI_PHYSICAL_ADDRESS FvbBaseAddress
;
248 EFI_FVB_ATTRIBUTES_2 FvbAttributes
;
249 EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL
*Fvb
;
252 // Locate all handles of SMM Fvb protocol.
254 Status
= GetFvbCountAndBuffer (&HandleCount
, &HandleBuffer
);
255 if (EFI_ERROR (Status
)) {
260 // Find the proper SMM Fvb handle by the address and attributes.
262 for (Index
= 0; Index
< HandleCount
; Index
++) {
263 Status
= FtwGetFvbByHandle (HandleBuffer
[Index
], &Fvb
);
264 if (EFI_ERROR (Status
)) {
268 // Compare the address.
270 Status
= Fvb
->GetPhysicalAddress (Fvb
, &FvbBaseAddress
);
271 if (EFI_ERROR (Status
)) {
274 if (Address
!= FvbBaseAddress
) {
279 // Compare the attribute.
281 Status
= Fvb
->GetAttributes (Fvb
, &FvbAttributes
);
282 if (EFI_ERROR (Status
)) {
285 if (Attributes
!= FvbAttributes
) {
290 // Found the proper FVB handle.
292 *SmmFvbHandle
= HandleBuffer
[Index
];
293 FreePool (HandleBuffer
);
297 FreePool (HandleBuffer
);
302 Communication service SMI Handler entry.
304 This SMI handler provides services for the fault tolerant write wrapper driver.
306 Caution: This function requires additional review when modified.
307 This driver need to make sure the CommBuffer is not in the SMRAM range.
308 Also in FTW_FUNCTION_GET_LAST_WRITE case, check SmmFtwGetLastWriteHeader->Data +
309 SmmFtwGetLastWriteHeader->PrivateDataSize within communication buffer.
311 @param[in] DispatchHandle The unique handle assigned to this handler by SmiHandlerRegister().
312 @param[in] RegisterContext Points to an optional handler context which was specified when the
313 handler was registered.
314 @param[in, out] CommBuffer A pointer to a collection of data in memory that will be conveyed
315 from a non-SMM environment into an SMM environment.
316 @param[in, out] CommBufferSize The size of the CommBuffer.
318 @retval EFI_SUCCESS The interrupt was handled and quiesced. No other handlers
319 should still be called.
320 @retval EFI_WARN_INTERRUPT_SOURCE_QUIESCED The interrupt has been quiesced but other handlers should
322 @retval EFI_WARN_INTERRUPT_SOURCE_PENDING The interrupt is still pending and other handlers should still
324 @retval EFI_INTERRUPT_PENDING The interrupt could not be quiesced.
329 SmmFaultTolerantWriteHandler (
330 IN EFI_HANDLE DispatchHandle
,
331 IN CONST VOID
*RegisterContext
,
332 IN OUT VOID
*CommBuffer
,
333 IN OUT UINTN
*CommBufferSize
337 SMM_FTW_COMMUNICATE_FUNCTION_HEADER
*SmmFtwFunctionHeader
;
338 SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
*SmmGetMaxBlockSizeHeader
;
339 SMM_FTW_ALLOCATE_HEADER
*SmmFtwAllocateHeader
;
340 SMM_FTW_WRITE_HEADER
*SmmFtwWriteHeader
;
341 SMM_FTW_RESTART_HEADER
*SmmFtwRestartHeader
;
342 SMM_FTW_GET_LAST_WRITE_HEADER
*SmmFtwGetLastWriteHeader
;
344 EFI_HANDLE SmmFvbHandle
;
349 // If input is invalid, stop processing this SMI
351 if (CommBuffer
== NULL
|| CommBufferSize
== NULL
) {
355 if (*CommBufferSize
< SMM_FTW_COMMUNICATE_HEADER_SIZE
) {
359 if (InternalIsAddressInSmram ((EFI_PHYSICAL_ADDRESS
)(UINTN
)CommBuffer
, *CommBufferSize
)) {
360 DEBUG ((EFI_D_ERROR
, "SMM communication buffer size is in SMRAM!\n"));
364 SmmFtwFunctionHeader
= (SMM_FTW_COMMUNICATE_FUNCTION_HEADER
*)CommBuffer
;
368 // It will be not safe to expose the operations after End Of Dxe.
370 DEBUG ((EFI_D_ERROR
, "SmmFtwHandler: Not safe to do the operation: %x after End Of Dxe, so access denied!\n", SmmFtwFunctionHeader
->Function
));
371 SmmFtwFunctionHeader
->ReturnStatus
= EFI_ACCESS_DENIED
;
375 switch (SmmFtwFunctionHeader
->Function
) {
376 case FTW_FUNCTION_GET_MAX_BLOCK_SIZE
:
377 SmmGetMaxBlockSizeHeader
= (SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
*) SmmFtwFunctionHeader
->Data
;
378 InfoSize
= sizeof (SMM_FTW_GET_MAX_BLOCK_SIZE_HEADER
);
381 // SMRAM range check already covered before
383 if (InfoSize
> *CommBufferSize
- SMM_FTW_COMMUNICATE_HEADER_SIZE
) {
384 DEBUG ((EFI_D_ERROR
, "Data size exceed communication buffer size limit!\n"));
385 Status
= EFI_ACCESS_DENIED
;
389 Status
= FtwGetMaxBlockSize (
390 &mFtwDevice
->FtwInstance
,
391 &SmmGetMaxBlockSizeHeader
->BlockSize
395 case FTW_FUNCTION_ALLOCATE
:
396 SmmFtwAllocateHeader
= (SMM_FTW_ALLOCATE_HEADER
*) SmmFtwFunctionHeader
->Data
;
397 Status
= FtwAllocate (
398 &mFtwDevice
->FtwInstance
,
399 &SmmFtwAllocateHeader
->CallerId
,
400 SmmFtwAllocateHeader
->PrivateDataSize
,
401 SmmFtwAllocateHeader
->NumberOfWrites
405 case FTW_FUNCTION_WRITE
:
406 SmmFtwWriteHeader
= (SMM_FTW_WRITE_HEADER
*) SmmFtwFunctionHeader
->Data
;
407 if (SmmFtwWriteHeader
->PrivateDataSize
== 0) {
410 PrivateData
= (VOID
*)&SmmFtwWriteHeader
->Data
[SmmFtwWriteHeader
->Length
];
412 Status
= GetFvbByAddressAndAttribute (
413 SmmFtwWriteHeader
->FvbBaseAddress
,
414 SmmFtwWriteHeader
->FvbAttributes
,
417 if (!EFI_ERROR (Status
)) {
419 &mFtwDevice
->FtwInstance
,
420 SmmFtwWriteHeader
->Lba
,
421 SmmFtwWriteHeader
->Offset
,
422 SmmFtwWriteHeader
->Length
,
425 SmmFtwWriteHeader
->Data
430 case FTW_FUNCTION_RESTART
:
431 SmmFtwRestartHeader
= (SMM_FTW_RESTART_HEADER
*) SmmFtwFunctionHeader
->Data
;
432 Status
= GetFvbByAddressAndAttribute (
433 SmmFtwRestartHeader
->FvbBaseAddress
,
434 SmmFtwRestartHeader
->FvbAttributes
,
437 if (!EFI_ERROR (Status
)) {
438 Status
= FtwRestart (&mFtwDevice
->FtwInstance
, SmmFvbHandle
);
442 case FTW_FUNCTION_ABORT
:
443 Status
= FtwAbort (&mFtwDevice
->FtwInstance
);
446 case FTW_FUNCTION_GET_LAST_WRITE
:
447 SmmFtwGetLastWriteHeader
= (SMM_FTW_GET_LAST_WRITE_HEADER
*) SmmFtwFunctionHeader
->Data
;
448 if ((UINTN
)(~0) - SmmFtwGetLastWriteHeader
->PrivateDataSize
< OFFSET_OF (SMM_FTW_GET_LAST_WRITE_HEADER
, Data
)){
450 // Prevent InfoSize overflow
452 Status
= EFI_ACCESS_DENIED
;
455 InfoSize
= OFFSET_OF (SMM_FTW_GET_LAST_WRITE_HEADER
, Data
) + SmmFtwGetLastWriteHeader
->PrivateDataSize
;
458 // SMRAM range check already covered before
460 if (InfoSize
> *CommBufferSize
- SMM_FTW_COMMUNICATE_HEADER_SIZE
) {
461 DEBUG ((EFI_D_ERROR
, "Data size exceed communication buffer size limit!\n"));
462 Status
= EFI_ACCESS_DENIED
;
466 Status
= FtwGetLastWrite (
467 &mFtwDevice
->FtwInstance
,
468 &SmmFtwGetLastWriteHeader
->CallerId
,
469 &SmmFtwGetLastWriteHeader
->Lba
,
470 &SmmFtwGetLastWriteHeader
->Offset
,
471 &SmmFtwGetLastWriteHeader
->Length
,
472 &SmmFtwGetLastWriteHeader
->PrivateDataSize
,
473 (VOID
*)SmmFtwGetLastWriteHeader
->Data
,
474 &SmmFtwGetLastWriteHeader
->Complete
479 Status
= EFI_UNSUPPORTED
;
482 SmmFtwFunctionHeader
->ReturnStatus
= Status
;
489 SMM Firmware Volume Block Protocol notification event handler.
491 @param[in] Protocol Points to the protocol's unique identifier
492 @param[in] Interface Points to the interface instance
493 @param[in] Handle The handle on which the interface was installed
495 @retval EFI_SUCCESS SmmEventCallback runs successfully
500 FvbNotificationEvent (
501 IN CONST EFI_GUID
*Protocol
,
507 EFI_SMM_FAULT_TOLERANT_WRITE_PROTOCOL
*FtwProtocol
;
508 EFI_HANDLE SmmFtwHandle
;
511 // Just return to avoid install SMM FaultTolerantWriteProtocol again
512 // if SMM Fault Tolerant Write protocol had been installed.
514 Status
= gSmst
->SmmLocateProtocol (
515 &gEfiSmmFaultTolerantWriteProtocolGuid
,
517 (VOID
**) &FtwProtocol
519 if (!EFI_ERROR (Status
)) {
524 // Found proper FVB protocol and initialize FtwDevice for protocol installation
526 Status
= InitFtwProtocol (mFtwDevice
);
527 if (EFI_ERROR(Status
)) {
532 // Install protocol interface
534 Status
= gSmst
->SmmInstallProtocolInterface (
536 &gEfiSmmFaultTolerantWriteProtocolGuid
,
537 EFI_NATIVE_INTERFACE
,
538 &mFtwDevice
->FtwInstance
540 ASSERT_EFI_ERROR (Status
);
543 // Notify the Ftw wrapper driver SMM Ftw is ready
546 Status
= gBS
->InstallProtocolInterface (
548 &gEfiSmmFaultTolerantWriteProtocolGuid
,
549 EFI_NATIVE_INTERFACE
,
552 ASSERT_EFI_ERROR (Status
);
558 SMM END_OF_DXE protocol notification event handler.
560 @param Protocol Points to the protocol's unique identifier
561 @param Interface Points to the interface instance
562 @param Handle The handle on which the interface was installed
564 @retval EFI_SUCCESS SmmEndOfDxeCallback runs successfully
569 SmmEndOfDxeCallback (
570 IN CONST EFI_GUID
*Protocol
,
580 This function is the entry point of the Fault Tolerant Write driver.
582 @param[in] ImageHandle A handle for the image that is initializing this driver
583 @param[in] SystemTable A pointer to the EFI system table
585 @retval EFI_SUCCESS The initialization finished successfully.
586 @retval EFI_OUT_OF_RESOURCES Allocate memory error
587 @retval EFI_INVALID_PARAMETER Workspace or Spare block does not exist
592 SmmFaultTolerantWriteInitialize (
593 IN EFI_HANDLE ImageHandle
,
594 IN EFI_SYSTEM_TABLE
*SystemTable
598 EFI_HANDLE FtwHandle
;
599 EFI_SMM_ACCESS2_PROTOCOL
*SmmAccess
;
601 VOID
*SmmEndOfDxeRegistration
;
604 // Allocate private data structure for SMM FTW protocol and do some initialization
606 Status
= InitFtwDevice (&mFtwDevice
);
607 if (EFI_ERROR(Status
)) {
612 // Get SMRAM information
614 Status
= gBS
->LocateProtocol (&gEfiSmmAccess2ProtocolGuid
, NULL
, (VOID
**)&SmmAccess
);
615 ASSERT_EFI_ERROR (Status
);
618 Status
= SmmAccess
->GetCapabilities (SmmAccess
, &Size
, NULL
);
619 ASSERT (Status
== EFI_BUFFER_TOO_SMALL
);
621 Status
= gSmst
->SmmAllocatePool (
622 EfiRuntimeServicesData
,
624 (VOID
**)&mSmramRanges
626 ASSERT_EFI_ERROR (Status
);
628 Status
= SmmAccess
->GetCapabilities (SmmAccess
, &Size
, mSmramRanges
);
629 ASSERT_EFI_ERROR (Status
);
631 mSmramRangeCount
= Size
/ sizeof (EFI_SMRAM_DESCRIPTOR
);
634 // Register EFI_SMM_END_OF_DXE_PROTOCOL_GUID notify function.
636 Status
= gSmst
->SmmRegisterProtocolNotify (
637 &gEfiSmmEndOfDxeProtocolGuid
,
639 &SmmEndOfDxeRegistration
641 ASSERT_EFI_ERROR (Status
);
644 // Register FvbNotificationEvent () notify function.
646 Status
= gSmst
->SmmRegisterProtocolNotify (
647 &gEfiSmmFirmwareVolumeBlockProtocolGuid
,
648 FvbNotificationEvent
,
651 ASSERT_EFI_ERROR (Status
);
653 FvbNotificationEvent (NULL
, NULL
, NULL
);
656 /// Register SMM FTW SMI handler
658 Status
= gSmst
->SmiHandlerRegister (SmmFaultTolerantWriteHandler
, &gEfiSmmFaultTolerantWriteProtocolGuid
, &FtwHandle
);
659 ASSERT_EFI_ERROR (Status
);