reactos/ntoskrnl/io/flush.c

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