reactos/ntoskrnl/io/iowork.c

   1 /* $Id: iowork.c,v 1.5 2003/07/11 01:23:14 royce Exp $
   2  *
   3  * COPYRIGHT:          See COPYING in the top level directory
   4  * PROJECT:            ReactOS kernel
   5  * FILE:               reactos/ntoskrnl/io/iowork.c
   6  * PURPOSE:            Manage IO system work queues
   7  * PROGRAMMER:         David Welch (welch@mcmail.com)
   8  *                     Robert Dickenson (odin@pnc.com.au)
   9  * REVISION HISTORY:
  10  *       28/09/2002:   (RDD) Created from copy of ex/work.c
  11  */
  12
  13 /* INCLUDES ******************************************************************/
  14
  15 #include <ddk/ntddk.h>
  16 #include <internal/ps.h>
  17
  18 #define NDEBUG
  19 #include <internal/debug.h>
  20
  21 /* TYPES ********************************************************************/
  22
  23 typedef struct _IO_WORKITEM
  24 {
  25   WORK_QUEUE_ITEM Item;
  26   PDEVICE_OBJECT  DeviceObject;
  27   PIO_WORKITEM_ROUTINE WorkerRoutine;
  28   PVOID           Context;
  29 } IO_WORKITEM;
  30
  31 /* GLOBALS ******************************************************************/
  32
  33 #define TAG_IOWI TAG('I', 'O', 'W', 'I')
  34
  35 /* FUNCTIONS ****************************************************************/
  36
  37 VOID STDCALL STATIC
  38 IoWorkItemCallback(PVOID Parameter)
  39 {
  40   PIO_WORKITEM IoWorkItem = (PIO_WORKITEM)Parameter;
  41   PDEVICE_OBJECT DeviceObject = IoWorkItem->DeviceObject;
  42   IoWorkItem->WorkerRoutine(IoWorkItem->DeviceObject, IoWorkItem->Context);
  43   ObDereferenceObject(DeviceObject);
  44 }
  45
  46 /*
  47  * @implemented
  48  */
  49 VOID STDCALL
  50 IoQueueWorkItem(IN PIO_WORKITEM IoWorkItem,
  51                 IN PIO_WORKITEM_ROUTINE WorkerRoutine,
  52                 IN WORK_QUEUE_TYPE QueueType,
  53                 IN PVOID Context)
  54 /*
  55  * FUNCTION: Inserts a work item in a queue for one of the system worker
  56  * threads to process
  57  * ARGUMENTS:
  58  *        IoWorkItem = Item to insert
  59  *        QueueType = Queue to insert it in
  60  */
  61 {
  62   ExInitializeWorkItem(&IoWorkItem->Item, IoWorkItemCallback,
  63                        (PVOID)IoWorkItem);
  64   IoWorkItem->WorkerRoutine = WorkerRoutine;
  65   IoWorkItem->Context = Context;
  66   ObReferenceObjectByPointer(IoWorkItem->DeviceObject,
  67                              FILE_ALL_ACCESS,
  68                              NULL,
  69                              KernelMode);
  70   ExQueueWorkItem(&IoWorkItem->Item, QueueType);
  71 }
  72
  73 /*
  74  * @implemented
  75  */
  76 VOID STDCALL
  77 IoFreeWorkItem(PIO_WORKITEM IoWorkItem)
  78 {
  79   ExFreePool(IoWorkItem);
  80 }
  81
  82 /*
  83  * @implemented
  84  */
  85 PIO_WORKITEM STDCALL
  86 IoAllocateWorkItem(PDEVICE_OBJECT DeviceObject)
  87 {
  88   PIO_WORKITEM IoWorkItem = NULL;
  89
  90   IoWorkItem =
  91     ExAllocatePoolWithTag(NonPagedPool, sizeof(IO_WORKITEM), TAG_IOWI);
  92   if (IoWorkItem == NULL)
  93     {
  94       return(NULL);
  95     }
  96   RtlZeroMemory(IoWorkItem, sizeof(IO_WORKITEM));
  97   IoWorkItem->DeviceObject = DeviceObject;
  98   return(IoWorkItem);
  99 }
 100
 101 /* EOF */