startio例程学习.doc

能够保证各个并行的IRP顺序执行，即串行化。很多时候，对设备的操作必须是串行化，驱动程序有必要将并行的请求变成串行的请求，需要用到队列。并行运行（函数执行交织在一起） 如果想一次处理每个IRP，必须采用队列将处理串行化。采用“先来先服务”原则cppview plaincopyprint?1. typedefstruct_KDEVICE_QUEUE/IRP队列来实现串行2. CSHORTType;3. CSHORTSize;4. LIST_ENTRYdevicelisthead;5. KSPIN_LOCKLock;6. BOOLEANBusy;7. KDEVICE_QUEUE,*PKDEVICE_QUEUE,*RESTRICTED_POINTERPRKDEVICE_QUEUE;这个StartIO例程声明在DriverEntry中：pDriverObject-DriverStartIo = HelloDDKStartIO;运行再 DISPATCH_LEVEL 级别，不会被线程所打断。 这个例程 参数类似派遣函数，不敢没有返回值在声明时 加上#pragma LOCKEDCODE示例：在使用StartIO例程时，需要IRP的派遣函数返回挂起状态。调用cppview plaincopyprint?1. VOID2. IoStartPacket(3. INPDEVICE_OBJECTDeviceObject,4. INPIRPIrp,5. INPULONGKeyOPTIONAL,/Ifthisiszero,thepacketisinsertedatthetailofthedevicequeue.6. INPDRIVER_CANCELCancelFunctionOPTIONAL/Specifiestheentrypointforadriver-suppliedCancelroutine.7. );cppview plaincopyprint?1. VOID2. IoStartNextPacket(3. INPDEVICE_OBJECTDeviceObject,4. INBOOLEANCancelable5. );cppview plaincopyprint?1. BOOLEAN2. KeRemoveEntryDeviceQueue(/从设备队列中将该IRP抽取出来3. INPKDEVICE_QUEUEDeviceQueue,4. INPKDEVICE_QUEUE_ENTRYDeviceQueueEntry5. );StartIO例程 运行再DISPATCH_LEVEL级别，因此不能使用分页内存，否则会引起页故障，从而导致系统崩溃下面示例：应用程序示例：cppview plaincopyprint?1. #include2. #include3. #include4. 5. UINTWINAPIThread(LPVOIDcontext)6. 7. printf(EnterThreadn);8. /等待5秒9. OVERLAPPEDoverlap=0;10. overlap.hEvent=CreateEvent(NULL,FALSE,FALSE,NULL);11. UCHARbuffer10;12. ULONGulRead;13. 14. BOOLbRead=ReadFile(*(PHANDLE)context,buffer,10,&ulRead,&overlap);15. 16. /可以试验取消例程17. CancelIo(*(PHANDLE)context);/如果不注释这一句那么会正常执行两个HelloDDKRead18. 19. WaitForSingleObject(overlap.hEvent,INFINITE);20. printf(读取完毕!n);21. return0;22. 23. intmain()24. 25. HANDLEhDevice=26. CreateFile(.HelloDDK,27. GENERIC_READ|GENERIC_WRITE,28. FILE_SHARE_READ,29. NULL,30. OPEN_EXISTING,31. FILE_ATTRIBUTE_NORMAL|FILE_FLAG_OVERLAPPED,/此处设置FILE_FLAG_OVERLAPPED32. NULL);33. if(hDevice=INVALID_HANDLE_VALUE)34. 35. printf(OpenDevicefailed!);36. return1;37. 38. HANDLEhThread2;39. hThread0=(HANDLE)_beginthreadex(NULL,0,Thread,&hDevice,0,NULL);40. hThread1=(HANDLE)_beginthreadex(NULL,0,Thread,&hDevice,0,NULL);41. 42. /主线程等待两个子线程结束43. WaitForMultipleObjects(2,hThread,TRUE,INFINITE);44. 45. printf(两个子线程结束!n);46. /创建IRP_MJ_CLEANUPIRP47. CloseHandle(hDevice);48. 49. return0;50. 驱动代码：cppview plaincopyprint?1. #includeDriver.h2. 3. #pragmaLOCKEDCODE4. VOID5. HelloDDKStartIO(6. INPDEVICE_OBJECTDeviceObject,7. INPIRPIrp8. )9. 10. KIRQLoldirql;11. KdPrint(EnterHelloDDKStartIOn);12. 13. /获取cancel自旋锁14. IoAcquireCancelSpinLock(&oldirql);15. if(Irp!=DeviceObject-CurrentIrp|Irp-Cancel)16. 17. /如果当前有正在处理的IRP，则简单的入队列，并直接返回18. /入队列的工作由系统完成，在StartIO中不用负责19. KdPrint(如果当前有正在处理的IRP，则简单的入队列，并直接返回n);20. IoReleaseCancelSpinLock(oldirql);21. KdPrint(LeaveHelloDDKStartIOn);22. return;23. else24. 25. /由于正在处理该IRP，所以不允许调用取消例程26. /因此将此IRP的取消例程设置为NULL27. KdPrint(由于正在处理该IRP，所以不允许调用取消例程n);28. IoSetCancelRoutine(Irp,NULL);29. IoReleaseCancelSpinLock(oldirql);30. 31. 32. KEVENTevent;33. KeInitializeEvent(&event,NotificationEvent,FALSE);34. 35. /等3秒36. KdPrint(等3秒n);37. LARGE_INTEGERtimeout;38. timeout.QuadPart=-3*1000*1000*10;39. 40. /定义一个3秒的延时，主要是为了模拟该IRP操作需要大概3秒左右时间41. KeWaitForSingleObject(&event,Executive,KernelMode,FALSE,&timeout);42. /SpecifiesaBooleanvaluethatisTRUEifthewaitisalertable43. 44. KdPrint(等3秒结束n);45. 46. Irp-IoStatus.Status=STATUS_SUCCESS;47. Irp-IoStatus.Information=0;/nobytesxfered48. IoCompleteRequest(Irp,IO_NO_INCREMENT);49. 50. 51. /在队列中读取一个IRP，并进行StartIo52. KdPrint(在队列中读取一个IRP，并进行StartIon);53. IoStartNextPacket(DeviceObject,TRUE);54. /1）true获取自旋锁55. /2）删除设备队列56. /3）获取IRP指针57. /4）设置IRP58. /5）true释放自旋锁59. /6）调用StartIo函数（设备对象，IRP）60. 61. KdPrint(LeaveHelloDDKStartIOn);62. 63. /*64. *函数名称:DriverEntry65. *功能描述:初始化驱动程序，定位和申请硬件资源，创建内核对象66. *参数列表:67. pDriverObject:从I/O管理器中传进来的驱动对象68. pRegistryPath:驱动程序在注册表的中的路径69. *返回值:返回初始化驱动状态70. */71. #pragmaINITCODE72. externCNTSTATUSDriverEntry(73. INPDRIVER_OBJECTpDriverObject,74. INPUNICODE_STRINGpRegistryPath)75. 76. NTSTATUSstatus;77. KdPrint(EnterDriverEntryn);78. 79. /设置卸载函数80. pDriverObject-DriverUnload=HelloDDKUnload;81. 82. /设置派遣函数83. pDriverObject-MajorFunctionIRP_MJ_CREATE=HelloDDKDispatchRoutin;84. pDriverObject-MajorFunctionIRP_MJ_CLOSE=HelloDDKDispatchRoutin;85. pDriverObject-MajorFunctionIRP_MJ_WRITE=HelloDDKDispatchRoutin;86. pDriverObject-MajorFunctionIRP_MJ_READ=HelloDDKRead;87. pDriverObject-MajorFunctionIRP_MJ_CLEANUP=HelloDDKDispatchRoutin;88. pDriverObject-MajorFunctionIRP_MJ_DEVICE_CONTROL=HelloDDKDispatchRoutin;89. pDriverObject-MajorFunctionIRP_MJ_SET_INFORMATION=HelloDDKDispatchRoutin;90. pDriverObject-MajorFunctionIRP_MJ_SHUTDOWN=HelloDDKDispatchRoutin;91. pDriverObject-MajorFunctionIRP_MJ_SYSTEM_CONTROL=HelloDDKDispatchRoutin;92. 93. /设置StartIO例程94. pDriverObject-DriverStartIo=HelloDDKStartIO;95. 96. /创建驱动设备对象97. status=CreateDevice(pDriverObject);98. 99. KdPrint(LeaveDriverEntryn);100. returnstatus;101. 102. /*103. *函数名称:CreateDevice104. *功能描述:初始化设备对象105. *参数列表:106. pDriverObject:从I/O管理器中传进来的驱动对象107. *返回值:返回初始化状态108. */109. #pragmaINITCODE110. NTSTATUSCreateDevice(111. INPDRIVER_OBJECTpDriverObject)112. 113. NTSTATUSstatus;114. PDEVICE_OBJECTpDevObj;115. PDEVICE_EXTENSIONpDevExt;116. 117. /创建设备名称118. UNICODE_STRINGdevName;119. RtlInitUnicodeString(&devName,LDeviceMyDDKDevice);120. 121. /创建设备122. status=IoCreateDevice(pDriverObject,123. sizeof(DEVICE_EXTENSION),124. &(UNICODE_STRING)devName,125. FILE_DEVICE_UNKNOWN,126. 0,TRUE,127. &pDevObj);128. if(!NT_SUCCESS(status)129. returnstatus;130. 131. pDevObj-Flags|=DO_BUFFERED_IO;132. pDevExt=(PDEVICE_EXTENSION)pDevObj-DeviceExtension;133. pDevExt-pDevice=pDevObj;134. pDevExt-ustrDeviceName=devName;135. 136. /创建符号链接137. UNICODE_STRINGsymLinkName;138. RtlInitUnicodeString(&symLinkName,L?HelloDDK);139. pDevExt-ustrSymLinkName=symLinkName;140. status=IoCreateSymbolicLink(&symLinkName,&devName);141. if(!NT_SUCCESS(status)142. 143. IoDeleteDevice(pDevObj);144. returnstatus;145. 146. returnSTATUS_SUCCESS;147. 148. /*149. *函数名称:HelloDDKUnload150. *功能描述:负责驱动程序的卸载操作151. *参数列表:152. pDriverObject:驱动对象153. *返回值:返回状态154. */155. #pragmaPAGEDCODE156. VOIDHelloDDKUnload(INPDRIVER_OBJECTpDriverObject)157. 158. PDEVICE_OBJECTpNextObj;159. KdPrint(EnterDriverUnloadn);160. pNextObj=pDriverObject-DeviceObject;161. while(pNextObj!=NULL)162. 163. PDEVICE_EXTENSIONpDevExt=(PDEVICE_EXTENSION)164. pNextObj-DeviceExtension;165. 166. /删除符号链接167. UNICODE_STRINGpLinkName=pDevExt-ustrSymLinkName;168. IoDeleteSymbolicLink(&pLinkName);169. 170. pNextObj=pNextObj-NextDevice;171. IoDeleteDevice(pDevExt-pDevice);172. 173. 174. /*175. *函数名称:HelloDDKDispatchRoutin176. *功能描述:对读IRP进行处理177. *参数列表:178. pDevObj:功能设备对象179. pIrp:从IO请求包180. *返回值:返回状态181. */182. #pragmaPAGEDCODE183. NTSTATUSHelloDDKDispatchRoutin(INPDEVICE_OBJECTpDevObj,184. INPIRPpIrp)185. 186. KdPrint(EnterHelloDDKDispatchRoutinn);187. PIO_STACK_LOCATIONstack=IoGetCurrentIrpStackLocation(pIrp);188. /建立一个字符串数组与IRP类型对应起来189. staticchar*irpname=190. 191. IRP_MJ_CREATE,192. IRP_MJ_CREATE_NAMED_PIPE,193. IRP_MJ_CLOSE,194. IRP_MJ_READ,195. IRP_MJ_WRITE,196. IRP_MJ_QUERY_INFORMATION,197. IRP_MJ_SET_INFORMATION,198. IRP_MJ_QUERY_EA,199. IRP_MJ_SET_EA,200. IRP_MJ_FLUSH_BUFFERS,201. IRP_MJ_QUERY_VOLUME_INFORMATION,202. IRP_MJ_SET_VOLUME_INFORMATION,203. IRP_MJ_DIRECTORY_CONTROL,204. IRP_MJ_FILE_SYSTEM_CONTROL,205. IRP_MJ_DEVICE_CONTROL,206. IRP_MJ_INTERNAL_DEVICE_CONTROL,207. IRP_MJ_SHUTDOWN,208. IRP_MJ_LOCK_CONTROL,209. IRP_MJ_CLEANUP,210. IRP_MJ_CREATE_MAILSLOT,211. IRP_MJ_QUERY_SECURITY,212. IRP_MJ_SET_SECURITY,213. IRP_MJ_POWER,214. IRP_MJ_SYSTEM_CONTROL,215. IRP_MJ_DEVICE_CHANGE,216. IRP_MJ_QUERY_QUOTA,217. IRP_MJ_SET_QUOTA,218. IRP_MJ_PNP,219. ;220. UCHARtype=stack-MajorFunction;221. if(type=arraysize(irpname)222. KdPrint(-UnknownIRP,majortype%Xn,type);223. else224. KdPrint(t%sn,irpnametype);225. 226. 227. /对一般IRP的简单操作，后面会介绍对IRP更复杂的操作228. NTSTATUSstatus=STATUS_SUCCESS;229. /完成IRP230. pIrp-IoStatus.Status=status;231. pIrp-IoStatus.Information=0;/bytesxfered232. IoCompleteRequest(pIrp,IO_NO_INCREMENT);233. 234. KdPrint(LeaveHelloDDKDispatchRoutinn);235. 236. returnstatus;237. 238. VOID239. OnCancelIRP(/如果在应用程序中调用CancelIo取消例程那么就会执行OnCancelIRP240. INPDEVICE_OBJECTDeviceObject,241. INPIRPIrp242. )243. 244. KdPrint(EnterCancelReadIRPn);245. 246. if(Irp=DeviceObject-CurrentIrp)247. 248. /表明当前正在改由StartIo处理249. KdPrint(当前正在改由StartIo处理n);250. /但StartIo并没有获取cancel自旋锁之前251. /这时候需要252. KIRQLoldirql=Irp-CancelIrql;253. 254. /释放Cancel自旋锁255. IoReleaseCancelSpinLock(Irp-CancelIrql);256. 257. IoStartNextPacket(DeviceObje