ntoskrnl/fsrtl/faulttol.c

   1 /*
   2  * PROJECT:         ReactOS Kernel
   3  * LICENSE:         GPL - See COPYING in the top level directory
   4  * FILE:            ntoskrnl/fsrtl/faulttol.c
   5  * PURPOSE:         Provides Fault Tolerance support for File System Drivers
   6  * PROGRAMMERS:     Alex Ionescu (alex.ionescu@reactos.org)
   7  */
   8
   9 /* INCLUDES ******************************************************************/
  10
  11 #include <ntoskrnl.h>
  12 #include "ntddft.h"
  13 #define NDEBUG
  14 #include <debug.h>
  15
  16 /* PUBLIC FUNCTIONS **********************************************************/
  17
  18 /*++
  19  * @name FsRtlBalanceReads
  20  * @implemented NT 5.2
  21  *
  22  *     The FsRtlBalanceReads routine sends an IRP to an FTDISK Driver
  23  *     requesting the driver to balance read requests across a mirror set.
  24  *
  25  * @param TargetDevice
  26  *        A pointer to an FTDISK Device Object.
  27  *
  28  * @return The NTSTATUS error code returned by the FTDISK Driver.
  29  *
  30  * @remarks FTDISK is a Software RAID Implementation.
  31  *
  32  *--*/
  33 NTSTATUS
  34 NTAPI
  35 FsRtlBalanceReads(PDEVICE_OBJECT TargetDevice)
  36 {
  37     PIRP Irp;
  38     KEVENT Event;
  39     IO_STATUS_BLOCK IoStatusBlock;
  40     NTSTATUS Status;
  41
  42     /* Initialize the Local Event */
  43     KeInitializeEvent(&Event, NotificationEvent, FALSE);
  44
  45     /* Build the special IOCTL */
  46     Irp = IoBuildDeviceIoControlRequest(FT_BALANCED_READ_MODE,
  47                                         TargetDevice,
  48                                         NULL,
  49                                         0,
  50                                         NULL,
  51                                         0,
  52                                         FALSE,
  53                                         &Event,
  54                                         &IoStatusBlock);
  55     if (!Irp) return STATUS_INSUFFICIENT_RESOURCES;
  56
  57     /* Send it */
  58     Status = IoCallDriver(TargetDevice, Irp);
  59
  60     /* Wait if needed */
  61     if (Status == STATUS_PENDING)
  62     {
  63         Status = KeWaitForSingleObject(&Event,
  64                                        Executive,
  65                                        KernelMode,
  66                                        FALSE,
  67                                        NULL);
  68         ASSERT(Status == STATUS_SUCCESS);
  69
  70         /* Return Status */
  71         Status = IoStatusBlock.Status;
  72     }
  73
  74     /* Return the status */
  75     return Status;
  76 }
  77
  78 /*++
  79  * @name FsRtlSyncVolumes
  80  * @implemented NT 5.2
  81  *
  82  *     The FsRtlSyncVolumes routine is deprecated.
  83  *
  84  * @return Always returns STATUS_SUCCESS.
  85  *
  86  * @remarks Deprecated.
  87  *
  88  *--*/
  89 NTSTATUS
  90 NTAPI
  91 FsRtlSyncVolumes(ULONG Unknown0,
  92                  ULONG Unknown1,
  93                  ULONG Unknown2)
  94 {
  95     /* Always return success */
  96     return STATUS_SUCCESS;
  97 }