datahub.c

EFI BIOS是Intel提出的下一代的BIOS标准。这里上传的Edk源代码是EFI BIOS源代码中的与平台无关部分的代码

/*++

Copyright (c) 2004 - 2005, Intel Corporation                                                         
All rights reserved. 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.             

Module Name:

  DataHub.c

Abstract:

  This code produces the Data Hub protocol. It preloads the data hub
  with status information copied in from PEI HOBs.
  
  Only code that implements the Data Hub protocol should go in this file!

  The Term MTC stands for MonoTonicCounter. 

  For more information please look at DataHub.doc

  NOTE: For extra security of the log GetNextDataRecord () could return a copy
        of the data record.
--*/

#include "DataHub.h"

//
// Worker functions private to this file
//
STATIC
DATA_HUB_FILTER_DRIVER  *
FindFilterDriverByEvent (
  IN  EFI_LIST_ENTRY  *Head,
  IN  EFI_EVENT       Event
  );

STATIC
EFI_DATA_RECORD_HEADER  *
GetNextDataRecord (
  IN  EFI_LIST_ENTRY      *Head,
  IN  UINT64              ClassFilter,
  IN OUT  UINT64          *PtrCurrentMTC
  );

EFI_STATUS
EFIAPI
DataHubLogData (
  IN  EFI_DATA_HUB_PROTOCOL   *This,
  IN  EFI_GUID                *DataRecordGuid,
  IN  EFI_GUID                *ProducerName,
  IN  UINT64                  DataRecordClass,
  IN  VOID                    *RawData,
  IN  UINT32                  RawDataSize
  )
/*++

Routine Description:

  Log data record into the data logging hub

Arguments:

  This                - Protocol instance structure

  DataRecordGuid      - GUID that defines record contents

  ProducerName        - GUID that defines the name of the producer of the data

  DataRecordClass     - Class that defines generic record type

  RawData             - Data Log record as defined by DataRecordGuid
  
  RawDataSize         - Size of Data Log data in bytes

Returns: 

  EFI_SUCCESS           - If data was logged

  EFI_OUT_OF_RESOURCES  - If data was not logged due to lack of system 
                           resources.
--*/
{
  EFI_STATUS              Status;
  DATA_HUB_INSTANCE       *Private;
  EFI_DATA_ENTRY          *LogEntry;
  UINT32                  TotalSize;
  UINT32                  RecordSize;
  EFI_DATA_RECORD_HEADER  *Record;
  VOID                    *Raw;
  DATA_HUB_FILTER_DRIVER  *FilterEntry;
  EFI_LIST_ENTRY          *Link;
  EFI_LIST_ENTRY          *Head;
  EFI_GUID                ZeroGuid  = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

  Private = DATA_HUB_INSTANCE_FROM_THIS (This);

  //
  // Combine the storage for the internal structs and a copy of the log record.
  //  Record follows PrivateLogEntry. The consumer will be returned a pointer
  //  to Record so we don't what it to be the thing that was allocated from
  //  pool, so the consumer can't free an data record by mistake.
  //
  RecordSize  = sizeof (EFI_DATA_RECORD_HEADER) + RawDataSize;
  TotalSize   = sizeof (EFI_DATA_ENTRY) + RecordSize;

  //
  // The Logging action is the critical section, so it is locked.
  //  The MTC asignment & update, time, and logging must be an
  //  atomic operation, so use the lock.
  //
  Status = EfiAcquireLockOrFail (&Private->DataLock);
  if (EFI_ERROR (Status)) {
    //
    // Reentrancy detected so exit!
    //
    return Status;
  }

  Status = gBS->AllocatePool (EfiBootServicesData, TotalSize, (VOID **) &LogEntry);
  if (EFI_ERROR (Status)) {
    EfiReleaseLock (&Private->DataLock);
    return EFI_OUT_OF_RESOURCES;
  }

  EfiZeroMem (LogEntry, TotalSize);

  Record  = (EFI_DATA_RECORD_HEADER *) (LogEntry + 1);
  Raw     = (VOID *) (Record + 1);

  //
  // Build Standard Log Header
  //
  Record->Version     = EFI_DATA_RECORD_HEADER_VERSION;
  Record->HeaderSize  = sizeof (EFI_DATA_RECORD_HEADER);
  Record->RecordSize  = RecordSize;
  EfiCopyMem (&Record->DataRecordGuid, DataRecordGuid, sizeof (EFI_GUID));
  EfiCopyMem (&Record->ProducerName, ProducerName, sizeof (EFI_GUID));
  Record->DataRecordClass   = DataRecordClass;

  Record->LogMonotonicCount = Private->GlobalMonotonicCount++;

  gRT->GetTime (&Record->LogTime, NULL);

  //
  // Insert log into the internal linked list.
  //
  LogEntry->Signature   = EFI_DATA_ENTRY_SIGNATURE;
  LogEntry->Record      = Record;
  LogEntry->RecordSize  = sizeof (EFI_DATA_ENTRY) + RawDataSize;
  InsertTailList (&Private->DataListHead, &LogEntry->Link);

  EfiCopyMem (Raw, RawData, RawDataSize);

  EfiReleaseLock (&Private->DataLock);

  //
  // Send Signal to all the filter drivers which are interested
  //  in the record's class and guid.
  //
  Head = &Private->FilterDriverListHead;
  for (Link = Head->ForwardLink; Link != Head; Link = Link->ForwardLink) {
    FilterEntry = FILTER_ENTRY_FROM_LINK (Link);
    if (((FilterEntry->ClassFilter & DataRecordClass) != 0) &&
        (EfiCompareGuid (&FilterEntry->FilterDataRecordGuid, &ZeroGuid) || 
         EfiCompareGuid (&FilterEntry->FilterDataRecordGuid, DataRecordGuid))) {
      gBS->SignalEvent (FilterEntry->Event);
    }
  }

  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
DataHubGetNextRecord (
  IN EFI_DATA_HUB_PROTOCOL            *This,
  IN OUT UINT64                       *MonotonicCount,
  IN EFI_EVENT                        *FilterDriverEvent, OPTIONAL
  OUT EFI_DATA_RECORD_HEADER          **Record
  )
/*++

Routine Description:

  Get a previously logged data record and the MonotonicCount for the next
  availible Record. This allows all records or all records later 
  than a give MonotonicCount to be returned. If an optional FilterDriverEvent
  is passed in with a MonotonicCout of zero return the first record 
  not yet read by the filter driver. If FilterDriverEvent is NULL and 
  MonotonicCount is zero return the first data record.

Arguments:

  This              - The EFI_DATA_HUB_PROTOCOL instance.
  MonotonicCount    - Specifies the Record to return. On input, zero means
                      return the first record. On output, contains the next
                      record to availible. Zero indicates no more records.
  FilterDriverEvent - If FilterDriverEvent is not passed in a MonotonicCount 
                      of zero, it means to return the first data record. 
                      If FilterDriverEvent is passed in, then a MonotonicCount 
                      of zero means to return the first data not yet read by 
                      FilterDriverEvent.
  Record            - Returns a dynamically allocated memory buffer with a data 
                      record that matches MonotonicCount.

Returns: 

  EFI_SUCCESS             - Data was returned in Record.
  EFI_INVALID_PARAMETER   - FilterDriverEvent was passed in but does not exist.
  EFI_NOT_FOUND           - MonotonicCount does not match any data record in the
                            system. If a MonotonicCount of zero was passed in, then
                            no data records exist in the system.
  EFI_OUT_OF_RESOURCES    - Record was not returned due to lack of system resources.

--*/
{
  DATA_HUB_INSTANCE       *Private;
  DATA_HUB_FILTER_DRIVER  *FilterDriver;
  UINT64                  ClassFilter;
  UINT64                  FilterMonotonicCount;

  Private               = DATA_HUB_INSTANCE_FROM_THIS (This);

  FilterDriver          = NULL;
  FilterMonotonicCount  = 0;
  ClassFilter = EFI_DATA_RECORD_CLASS_DEBUG |
    EFI_DATA_RECORD_CLASS_ERROR |
    EFI_DATA_RECORD_CLASS_DATA |
    EFI_DATA_RECORD_CLASS_PROGRESS_CODE;

  if (FilterDriverEvent != NULL) {
    //
    // For events the beginning is the last unread record. This info is
    // stored in the instance structure, so we must look up the event
    // to get the data.
    //
    FilterDriver = FindFilterDriverByEvent (
                    &Private->FilterDriverListHead,
                    *FilterDriverEvent
                    );
    if (FilterDriver == NULL) {
      return EFI_INVALID_PARAMETER;
    }
    //
    // Use the Class filter the event was created with.
    //
    ClassFilter = FilterDriver->ClassFilter;

    if (*MonotonicCount == 0) {
      //
      // Use the MTC from the Filter Driver.
      //
      FilterMonotonicCount = FilterDriver->GetNextMonotonicCount;
      if (FilterMonotonicCount != 0) {
        //
        // The GetNextMonotonicCount field remembers the last value from the previous time.
        // But we already processed this vaule, so we need to find the next one. So if
        // It is not the first time get the new record entry.
        //
        *Record         = GetNextDataRecord (&Private->DataListHead, ClassFilter, &FilterMonotonicCount);
        *MonotonicCount = FilterMonotonicCount;
        if (FilterMonotonicCount == 0) {
          //
          // If there is no new record to get exit now.
          //
          return EFI_NOT_FOUND;
        }
      }
    }
  }
  //
  // Return the record
  //
  *Record = GetNextDataRecord (&Private->DataListHead, ClassFilter, MonotonicCount);
  if (*Record == NULL) {
    return EFI_NOT_FOUND;
  }

  if (FilterDriver != NULL) {
    //
    // If we have a filter driver update the records that have been read.
    // If MonotonicCount is zero No more reacords left.
    //
    if (*MonotonicCount == 0) {
      if (FilterMonotonicCount != 0) {
        //
        // Return the result of our extra GetNextDataRecord.
        //
        FilterDriver->GetNextMonotonicCount = FilterMonotonicCount;
      }
    } else {
      //
      // Point to next undread record
      //
      FilterDriver->GetNextMonotonicCount = *MonotonicCount;
    }
  }

  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
DataHubRegisterFilterDriver (
  IN EFI_DATA_HUB_PROTOCOL    * This,
  IN EFI_EVENT                FilterEvent,
  IN EFI_TPL                  FilterTpl,
  IN UINT64                   FilterClass,
  IN EFI_GUID                 * FilterDataRecordGuid OPTIONAL
  )
/*++

Routine Description:

  This function registers the data hub filter driver that is represented 
  by FilterEvent. Only one instance of each FilterEvent can be registered.
  After the FilterEvent is registered, it will be signaled so it can sync 
  with data records that have been recorded prior to the FilterEvent being 
  registered.
    
Arguments:

  This                  - The EFI_DATA_HUB_PROTOCOL instance.
  FilterEvent           - The EFI_EVENT to signal whenever data that matches