Writing Device Drivers

Block Driver Structure Overview

Figure 16–1 shows data structures and routines that define the structure of a block device driver. Device drivers typically include the following elements:

The shaded device access section in the following figure illustrates entry points for block drivers.

Figure 16–1 Block Driver Roadmap

Diagram shows structures and entry points for block device

Associated with each device driver is a dev_ops(9S) structure, which in turn refers to a cb_ops(9S) structure. See Chapter 6, Driver Autoconfiguration for details on driver data structures.

Block device drivers provide these entry points:

Note –

Some of the entry points can be replaced by nodev(9F) or nulldev(9F) as appropriate.