reactos/ntoskrnl/io/flush.c

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS kernel
   4  * FILE:            ntoskrnl/io/flush.c
   5  * PURPOSE:         Flushing file buffer
   6  * PROGRAMMER:      David Welch (welch@cwcom.net)
   7  * UPDATE HISTORY:
   8  *                  Created 22/05/98
   9  */
  10
  11 /* INCLUDES *****************************************************************/
  12
  13 #include <ddk/ntddk.h>
  14 #include <internal/ob.h>
  15
  16 #define NDEBUG
  17 #include <internal/debug.h>
  18
  19 /* FUNCTIONS *****************************************************************/
  20
  21
  22 NTSTATUS
  23 STDCALL
  24 NtFlushWriteBuffer(VOID)
  25 {
  26   KeFlushWriteBuffer();
  27   return STATUS_SUCCESS;
  28 }
  29
  30 NTSTATUS
  31 STDCALL
  32 NtFlushBuffersFile (
  33         IN      HANDLE                  FileHandle,
  34         OUT     PIO_STATUS_BLOCK        IoStatusBlock
  35         )
  36 /*
  37  * FUNCTION: Flushes cached file data to disk
  38  * ARGUMENTS:
  39  *       FileHandle = Points to the file
  40  *       IoStatusBlock = Caller must supply storage to receive the result of
  41  *                       the flush buffers operation. The information field is
  42  *                       set to number of bytes flushed to disk.
  43  * RETURNS: Status
  44  * REMARKS: This function maps to the win32 FlushFileBuffers
  45  */
  46 {
  47    PFILE_OBJECT FileObject = NULL;
  48    PIRP Irp;
  49    PIO_STACK_LOCATION StackPtr;
  50    NTSTATUS Status;
  51    KPROCESSOR_MODE PreviousMode;
  52
  53    PreviousMode = ExGetPreviousMode();
  54
  55    Status = ObReferenceObjectByHandle(FileHandle,
  56                                       FILE_WRITE_DATA,
  57                                       NULL,
  58                                       PreviousMode,
  59                                       (PVOID*)&FileObject,
  60                                       NULL);
  61    if (Status != STATUS_SUCCESS)
  62      {
  63         return(Status);
  64      }
  65    KeResetEvent( &FileObject->Event );
  66    Irp = IoBuildSynchronousFsdRequest(IRP_MJ_FLUSH_BUFFERS,
  67                                       FileObject->DeviceObject,
  68                                       NULL,
  69                                       0,
  70                                       NULL,
  71                                       &FileObject->Event,
  72                                       IoStatusBlock);
  73
  74    /* Trigger FileObject/Event dereferencing */
  75    Irp->Tail.Overlay.OriginalFileObject = FileObject;
  76
  77    Irp->RequestorMode = PreviousMode;
  78
  79    StackPtr = IoGetNextIrpStackLocation(Irp);
  80    StackPtr->FileObject = FileObject;
  81
  82    Status = IoCallDriver(FileObject->DeviceObject,Irp);
  83    if (Status == STATUS_PENDING)
  84      {
  85         KeWaitForSingleObject(&FileObject->Event,
  86                               Executive,
  87                               PreviousMode,
  88                               FileObject->Flags & FO_ALERTABLE_IO,
  89                               NULL);
  90         Status = IoStatusBlock->Status;
  91      }
  92
  93    return(Status);
  94 }