Dissecting Interrupts and Browsing DMA

This is the fourth in a series of articles about writing character device drivers as loadable kernel modules. This month, we further investigate the field of interrupt handling. Though it is conceptually simple, practical limitations and constraints make this an “interesting” part of device friver writing, and several different facilities have been provided for different situations. We also invest
Deeper and Further

If you want to go deeper with the topics just described, the best teacher is the source, as usual. Split-half interrupt handlers and task queues are used throughout the mainstream kernel, while the DMA implementation shown here is taken from our ceddrv-0.17, available by ftp from tsx-11.mit.edu.

The next installment will come back to more concrete issues—we realize that both DMA and task queues may appear to be rather esoteric topics. We'll show how mmap() works and how a driver may implement its semantics.

Alessandro Rubini is a 27-year-old Linuxer with a taste for the practical side of computer science and a tendency to delay sleeping. This helps him meet deadlines by exploiting time-zone offsets.

Georg V. Zezschwitz is also 27-year-old Linuxer with the same taste for the practical side of computer science and a tendency to delay sleeping.


One Click, Universal Protection: Implementing Centralized Security Policies on Linux Systems

As Linux continues to play an ever increasing role in corporate data centers and institutions, ensuring the integrity and protection of these systems must be a priority. With 60% of the world's websites and an increasing share of organization's mission-critical workloads running on Linux, failing to stop malware and other advanced threats on Linux can increasingly impact an organization's reputation and bottom line.

Learn More

Sponsored by Bit9

Linux Backup and Recovery Webinar

Most companies incorporate backup procedures for critical data, which can be restored quickly if a loss occurs. However, fewer companies are prepared for catastrophic system failures, in which they lose all data, the entire operating system, applications, settings, patches and more, reducing their system(s) to “bare metal.” After all, before data can be restored to a system, there must be a system to restore it to.

In this one hour webinar, learn how to enhance your existing backup strategies for better disaster recovery preparedness using Storix System Backup Administrator (SBAdmin), a highly flexible bare-metal recovery solution for UNIX and Linux systems.

Learn More

Sponsored by Storix