6. Device Management

See also

• Video Lecture about Device and IO Management

Hardware devices typically provide the ability to input data into the computer or output data from the computer. To simplify the ability to support a variety of hardware devices, standardized application programming interfaces (API) are used.

• Application programs use the System Call API to request one of a finite set of preset I/O requests from the Operating System.
• The Operating System uses algorithms for processing the request that are device independent.
• The Operating System uses another API to request data from the device driver.
• The device driver is third party software that knows how to interact with the specific device to perform the I/O.
• Sometimes we have a layering of device drivers where one device driver will call on another device driver to facilitate the I/O. An example of this is when devices are connected to a USB port. The driver for the device will make use of the USB device driver to facilitate passing data to and from the device.

Contents:

• 6.1. Device Drivers
  • 6.1.1. The Device Driver Interface
  • 6.1.2. Device Driver Layers
  • 6.1.3. System Call Interface
  • 6.1.4. Example - UNIX Driver
• 6.2. Waiting for I/O
  • 6.2.1. Polling
  • 6.2.2. Interrupt Driven
• 6.3. The Top and Bottom Halves of Drivers
• 6.4. Device Driver Implementation
  • 6.4.1. Device Independent Function Call
  • 6.4.2. Driver–Kernel Interface
  • 6.4.3. Reconfigurable Device Drivers
• 6.5. Using Buffers to Improve Performance