diff options
Diffstat (limited to 'MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c')
-rw-r--r-- | MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c new file mode 100644 index 0000000..5f998c0 --- /dev/null +++ b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c @@ -0,0 +1,250 @@ +/** @file
+
+ This is a simple fault tolerant write driver.
+
+ This boot service protocol only provides fault tolerant write capability for
+ block devices. The protocol has internal non-volatile intermediate storage
+ of the data and private information. It should be able to recover
+ automatically from a critical fault, such as power failure.
+
+ The implementation uses an FTW (Fault Tolerant Write) Work Space.
+ This work space is a memory copy of the work space on the Working Block,
+ the size of the work space is the FTW_WORK_SPACE_SIZE bytes.
+
+ The work space stores each write record as EFI_FTW_RECORD structure.
+ The spare block stores the write buffer before write to the target block.
+
+ The write record has three states to specify the different phase of write operation.
+ 1) WRITE_ALLOCATED is that the record is allocated in write space.
+ The information of write operation is stored in write record structure.
+ 2) SPARE_COMPLETED is that the data from write buffer is writed into the spare block as the backup.
+ 3) WRITE_COMPLETED is that the data is copied from the spare block to the target block.
+
+ This driver operates the data as the whole size of spare block.
+ It first read the SpareAreaLength data from the target block into the spare memory buffer.
+ Then copy the write buffer data into the spare memory buffer.
+ Then write the spare memory buffer into the spare block.
+ Final copy the data from the spare block to the target block.
+
+ To make this drive work well, the following conditions must be satisfied:
+ 1. The write NumBytes data must be fit within Spare area.
+ Offset + NumBytes <= SpareAreaLength
+ 2. The whole flash range has the same block size.
+ 3. Working block is an area which contains working space in its last block and has the same size as spare block.
+ 4. Working Block area must be in the single one Firmware Volume Block range which FVB protocol is produced on.
+ 5. Spare area must be in the single one Firmware Volume Block range which FVB protocol is produced on.
+ 6. Any write data area (SpareAreaLength Area) which the data will be written into must be
+ in the single one Firmware Volume Block range which FVB protocol is produced on.
+ 7. If write data area (such as Variable range) is enlarged, the spare area range must be enlarged.
+ The spare area must be enough large to store the write data before write them into the target range.
+ If one of them is not satisfied, FtwWrite may fail.
+ Usually, Spare area only takes one block. That's SpareAreaLength = BlockSize, NumberOfSpareBlock = 1.
+
+Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
+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.
+
+**/
+
+#include "FaultTolerantWrite.h"
+EFI_EVENT mFvbRegistration = NULL;
+
+
+/**
+ Retrive the FVB protocol interface by HANDLE.
+
+ @param[in] FvBlockHandle The handle of FVB protocol that provides services for
+ reading, writing, and erasing the target block.
+ @param[out] FvBlock The interface of FVB protocol
+
+ @retval EFI_SUCCESS The interface information for the specified protocol was returned.
+ @retval EFI_UNSUPPORTED The device does not support the FVB protocol.
+ @retval EFI_INVALID_PARAMETER FvBlockHandle is not a valid EFI_HANDLE or FvBlock is NULL.
+
+**/
+EFI_STATUS
+FtwGetFvbByHandle (
+ IN EFI_HANDLE FvBlockHandle,
+ OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL **FvBlock
+ )
+{
+ //
+ // To get the FVB protocol interface on the handle
+ //
+ return gBS->HandleProtocol (
+ FvBlockHandle,
+ &gEfiFirmwareVolumeBlockProtocolGuid,
+ (VOID **) FvBlock
+ );
+}
+
+/**
+ Retrive the Swap Address Range protocol interface.
+
+ @param[out] SarProtocol The interface of SAR protocol
+
+ @retval EFI_SUCCESS The SAR protocol instance was found and returned in SarProtocol.
+ @retval EFI_NOT_FOUND The SAR protocol instance was not found.
+ @retval EFI_INVALID_PARAMETER SarProtocol is NULL.
+
+**/
+EFI_STATUS
+FtwGetSarProtocol (
+ OUT VOID **SarProtocol
+ )
+{
+ EFI_STATUS Status;
+
+ //
+ // Locate Swap Address Range protocol
+ //
+ Status = gBS->LocateProtocol (
+ &gEfiSwapAddressRangeProtocolGuid,
+ NULL,
+ SarProtocol
+ );
+ return Status;
+}
+
+/**
+ Function returns an array of handles that support the FVB protocol
+ in a buffer allocated from pool.
+
+ @param[out] NumberHandles The number of handles returned in Buffer.
+ @param[out] Buffer A pointer to the buffer to return the requested
+ array of handles that support FVB protocol.
+
+ @retval EFI_SUCCESS The array of handles was returned in Buffer, and the number of
+ handles in Buffer was returned in NumberHandles.
+ @retval EFI_NOT_FOUND No FVB handle was found.
+ @retval EFI_OUT_OF_RESOURCES There is not enough pool memory to store the matching results.
+ @retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
+
+**/
+EFI_STATUS
+GetFvbCountAndBuffer (
+ OUT UINTN *NumberHandles,
+ OUT EFI_HANDLE **Buffer
+ )
+{
+ EFI_STATUS Status;
+
+ //
+ // Locate all handles of Fvb protocol
+ //
+ Status = gBS->LocateHandleBuffer (
+ ByProtocol,
+ &gEfiFirmwareVolumeBlockProtocolGuid,
+ NULL,
+ NumberHandles,
+ Buffer
+ );
+ return Status;
+}
+
+
+/**
+ Firmware Volume Block Protocol notification event handler.
+
+ @param[in] Event Event whose notification function is being invoked.
+ @param[in] Context Pointer to the notification function's context.
+
+**/
+VOID
+EFIAPI
+FvbNotificationEvent (
+ IN EFI_EVENT Event,
+ IN VOID *Context
+ )
+{
+ EFI_STATUS Status;
+ EFI_FAULT_TOLERANT_WRITE_PROTOCOL *FtwProtocol;
+ EFI_FTW_DEVICE *FtwDevice;
+
+ //
+ // Just return to avoid install SMM FaultTolerantWriteProtocol again
+ // if Fault Tolerant Write protocol had been installed.
+ //
+ Status = gBS->LocateProtocol (
+ &gEfiFaultTolerantWriteProtocolGuid,
+ NULL,
+ (VOID **) &FtwProtocol
+ );
+ if (!EFI_ERROR (Status)) {
+ return ;
+ }
+
+ //
+ // Found proper FVB protocol and initialize FtwDevice for protocol installation
+ //
+ FtwDevice = (EFI_FTW_DEVICE *)Context;
+ Status = InitFtwProtocol (FtwDevice);
+ if (EFI_ERROR(Status)) {
+ return ;
+ }
+
+ //
+ // Install protocol interface
+ //
+ Status = gBS->InstallProtocolInterface (
+ &FtwDevice->Handle,
+ &gEfiFaultTolerantWriteProtocolGuid,
+ EFI_NATIVE_INTERFACE,
+ &FtwDevice->FtwInstance
+ );
+ ASSERT_EFI_ERROR (Status);
+
+ Status = gBS->CloseEvent (Event);
+ ASSERT_EFI_ERROR (Status);
+
+ return;
+}
+
+
+/**
+ This function is the entry point of the Fault Tolerant Write driver.
+
+ @param[in] ImageHandle A handle for the image that is initializing this driver
+ @param[in] SystemTable A pointer to the EFI system table
+
+ @retval EFI_SUCCESS The initialization finished successfully.
+ @retval EFI_OUT_OF_RESOURCES Allocate memory error
+ @retval EFI_INVALID_PARAMETER Workspace or Spare block does not exist
+
+**/
+EFI_STATUS
+EFIAPI
+FaultTolerantWriteInitialize (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+ EFI_FTW_DEVICE *FtwDevice;
+
+ //
+ // Allocate private data structure for FTW protocol and do some initialization
+ //
+ Status = InitFtwDevice (&FtwDevice);
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+
+ //
+ // Register FvbNotificationEvent () notify function.
+ //
+ EfiCreateProtocolNotifyEvent (
+ &gEfiFirmwareVolumeBlockProtocolGuid,
+ TPL_CALLBACK,
+ FvbNotificationEvent,
+ (VOID *)FtwDevice,
+ &mFvbRegistration
+ );
+
+ return EFI_SUCCESS;
+}
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