A Domain-Specific Language for Device Drivers

Device drivers have been noted as a major source of faults in operating system code [2]. Largely for efficiency, device drivers and other systems code have historically been written in low-level languages like C. Unfortunately, these languages do not provide the type safety and robustness one would expect in critical systems code. Work has been done to augment the type safety of low-level languages [3, 6], but the efficacy of this work is limited by both fundamental and practical concerns. In this paper, I will describe a domain-specific language and compiler for network interface device drivers. The language has been used to implement a driver for NE2000 network cards, a widely available class of inexpensive LAN adaptors. The language includes direct support for the operational semantics of device drivers and provides a high level of type safety. Concurrency semantics are included for the description of devices with multiple independent operational units. Though the language has been built for and tested on network drivers, it is flexible enough to describe a wider class of drivers. The compiler is also designed to be readily ported to a wider class of operating systems.