The Virtual File System in the last chapter depends on lower-level functions to carry out each read, write, or other operation in a manner suited to each device. The previous chapter included a brief discussion of how operations are handled by different filesystems. In this chapter, we look at how the kernel invokes the operations on actual devices.
In Section 13.1, we give a brief survey of the 80 x 86 I/O architecture. In Section 13.2, we show how the VFS associates a special file called "device file" with each different hardware device so that application programs can use all kinds of devices in the same way. Finally, in Section 13.3, we illustrate the overall organization of device drivers in Linux. Readers interested in developing device drivers on their own may want to refer to Alessandro Rubini and Jonathan Corbet's Linux Device Drivers (O'Reilly).
Was this article helpful?