ntoskrnl/io/iowork.c

   1 /* $Id$
   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   IoWorkItem->WorkerRoutine(IoWorkItem->DeviceObject, IoWorkItem->Context);
  42   ObDereferenceObject(IoWorkItem->DeviceObject);
  43 }
  44
  45 VOID STDCALL
  46 IoQueueWorkItem(IN PIO_WORKITEM IoWorkItem,
  47                 IN PIO_WORKITEM_ROUTINE WorkerRoutine,
  48                 IN WORK_QUEUE_TYPE QueueType,
  49                 IN PVOID Context)
  50 /*
  51  * FUNCTION: Inserts a work item in a queue for one of the system worker
  52  * threads to process
  53  * ARGUMENTS:
  54  *        IoWorkItem = Item to insert
  55  *        QueueType = Queue to insert it in
  56  */
  57 {
  58   ExInitializeWorkItem(&IoWorkItem->Item, IoWorkItemCallback,
  59                        (PVOID)IoWorkItem);
  60   IoWorkItem->WorkerRoutine = WorkerRoutine;
  61   IoWorkItem->Context = Context;
  62   ObReferenceObjectByPointer(IoWorkItem->DeviceObject,
  63                              FILE_ALL_ACCESS,
  64                              NULL,
  65                              KernelMode);
  66   ExQueueWorkItem(&IoWorkItem->Item, QueueType);
  67 }
  68
  69 VOID STDCALL
  70 IoFreeWorkItem(PIO_WORKITEM IoWorkItem)
  71 {
  72   ExFreePool(IoWorkItem);
  73 }
  74
  75 PIO_WORKITEM STDCALL
  76 IoAllocateWorkItem(PDEVICE_OBJECT DeviceObject)
  77 {
  78   PIO_WORKITEM IoWorkItem = NULL;
  79
  80   IoWorkItem =
  81     ExAllocatePoolWithTag(NonPagedPool, sizeof(IO_WORKITEM), TAG_IOWI);
  82   if (IoWorkItem == NULL)
  83     {
  84       return(NULL);
  85     }
  86   RtlZeroMemory(IoWorkItem, sizeof(IO_WORKITEM));
  87   IoWorkItem->DeviceObject = DeviceObject;
  88   return(IoWorkItem);
  89 }
  90
  91 /* EOF */