Kernel Space - User Space Interfaces

Kernel Space - User Space Interfaces

Ariane Keller mailto:ariane.zerospam.keller@tik.ee.ethz.ch

Version 0.8, July 2008

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This document looks at the numerous and interesting ways the Linux kernel 2.6 interacts with user space programs. We explain sockets, procfs (and similar virtual filesystems), creating new Linux system calls, as well as mundane file and memory handling.

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1. Introduction

• 1.1 Preamble
• 1.2 How to Use This Document and Intended Audience
• 1.3 Requirements to Use This Document
• 1.4 Obtain Example Source Code
• 1.5 Getting More Information
• 1.6 Disclaimer
• 1.7 Copyright

2. Procfs, Sysfs, and Similar Kernel Interfaces

• 2.1 Introduction
• 2.2 Procfs
• 2.3 Sysfs
• 2.4 Configfs
• 2.5 Debugfs
• 2.6 Sysctl
• 2.7 Character Devices

3. Socket Based Mechanisms

• 3.1 Introduction
• 3.2 UDP Sockets
• 3.3 Netlink Sockets

4. Ioctl

• 4.1 Introduction
• 4.2 Implementation
• 4.3 Resources and Further Reading

5. Kernel System Calls

• 5.1 Introduction
• 5.2 Implementation
• 5.3 Resources and Further Reading

6. Sending Signals from the Kernel to the User Space

• 6.1 Introduction
• 6.2 Implementation
• 6.3 Resources and Further Reading

7. Upcall

• 7.1 Introduction
• 7.2 Implementation
• 7.3 Resources and Further Reading

8. Mmap

• 8.1 Introduction
• 8.2 Implementation
• 8.3 Resources and Further Reading