Lecture 14: Monday, 22 July 2024

Announcements

  1. Midpoint presentation due by midnight tonight

  2. E2 due next week

  3. P2 released, due in two weeks


Review

  1. In L13 we covered:

    1. What is a character device?

    2. Why do we want to use character devices

    3. How does the user interact with character devices?

    4. How does a kernel module implement a character device?

    5. Demo: random number generator


Lecture overview

  1. Extend file_operations with write(2), ioctl(2), and llseek(2)

  2. Introduce the jiffies counter and HZ constant

  3. Discuss the device class system and struct device

  4. Overview of MIDI and our simplification

  5. Work through the design and implementation of kkey

  6. Listen to the sound of the kernel


Slides

Character Devices 2


msg = (silence)
whoami = None
singularity v0.5 https://github.com/underground-software/singularity