Roadmap for Section 6.3 Driver and Device Objects
{"Image DocumentName": "Roadmap for Section 6.3 Driver and Device Objects", "Image ImageDescription": "I/O Request Packets (IRP) Processing. Driver Layering and Filtering. Plug-and-Play (PnP) and Power Manager Operation. Monitoring I/O Activity with Filemon. Most I/O operations don\u2019t involve all the components of the I/O system. A typical I/O request starts with an application executing an I/O-related function (for example, reading data from a device) that is processed by the I/O manager, one or more device drivers, and the HAL. The I/O system is packet driven. Most I/O requests are represented by an I/O request packet (IRP), which travels from one I/O system component to another. The design allows an individual application thread to manage multiple I/O requests concurrently. An IRP is a data structure that contains information completely describing an I/O request. The I/O manager creates an IRP that represents an I/O operation, passing a pointer to the IRP to the correct driver and disposing of the packet when the I/O operation is complete. In contrast, a driver receives an IRP, performs the operation the IRP specifies, and passes the IRP back to the I/O manager, either for completion or to be passed on to another driver for further processing. Based on the IRP concept, we describe the asynchronous processing within the Windows I/O system in detail.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}