FreeBSD Device Drivers
From First Steps to Kernel Mastery
Learn how to write real, modern FreeBSD device drivers from scratch. No prior experience required.
This beginner-friendly, hands-on guide takes you on a complete journey into the world of FreeBSD driver development, one clear step at a time. Whether you're a curious student, aspiring systems programmer, embedded developer, or open-source enthusiast, this book gives you the practical skills and foundational knowledge to master kernel programming at your own pace.
You'll start from the very beginning, learning the UNIX environment and the C programming language before diving into the FreeBSD kernel itself. Guided by clear explanations, carefully annotated code, and real-world examples, you'll build your first driver in a safe virtual lab and grow it into a fully functional production-grade module.
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What You'll Learn
This comprehensive guide covers everything from UNIX fundamentals to advanced kernel programming, taking you from complete beginner to confident FreeBSD device driver developer.
- •Understand FreeBSD from the inside out, even without prior UNIX experience
- •Set up complete development and testing environment for kernel development
- •Master UNIX command line, text editors, and essential system utilities
- •Learn C programming with focus on kernel-specific usage patterns
- •Explore FreeBSD kernel modules and device driver architecture
- •Write, load, test, and debug your first real device driver
- •Interact with device files and user-space communication
- •Implement safe and efficient input/output operations with devices
- •Manage concurrency and multi-process support safely
- •Use mutexes, semaphores, and condition variables effectively
- •Implement timers and delayed work for time-based operations
- •Master memory-mapped I/O and hardware register access
- •Build and simulate hardware devices for testing
- •Develop PCI device drivers with resource management
- •Handle hardware interrupts including MSI/MSI-X mechanisms
- •Implement DMA for high-speed data transfers
- •Debug drivers using printf, tracing, and DTrace
- •Analyze crashes, read kernel dumps, and debug panics
- •Profile and optimize driver performance
- •Follow security best practices to avoid vulnerabilities
- •Write portable drivers across FreeBSD, NetBSD, and Linux
- •Handle USB and serial devices with bus-specific protocols
- •Work with embedded systems and Device Tree (FDT)
- •Submit drivers to FreeBSD Project and contribute to open source
Plus Comprehensive Appendices
Essential Skills & Knowledge:
- • Build strong C programming foundation for systems work
- • Develop logic and problem-solving skills for low-level code
- • Master hardware concepts: interrupts, buses, and DMA
- • Understand OS concepts: processes, memory, system calls
Advanced Topics & Integration:
- • Work with virtualized environments (bhyve, jails)
- • Handle hot-plugging and dynamic configuration
- • Implement asynchronous I/O and event-driven techniques
- • Dive deep into FreeBSD internals and kernel APIs
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