reactos/ntoskrnl/io/iowork.c

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