A learning operating system to get a deeper knowledge in the system software design
Find a file
2014-12-04 21:44:02 +01:00
arch/x86 added proper accounting of user used page frames 2014-12-04 21:44:02 +01:00
documentation fix typo in URL 2014-08-10 07:06:16 +02:00
include/eduos get_current_stack set CR3 => required for a context switch 2014-12-03 23:10:32 +01:00
kernel added proper accounting of user used page frames 2014-12-04 21:44:02 +01:00
libkern extending example task, fix bug in handling of the TSS 2014-01-22 12:13:30 +01:00
mm simplified code, fixed smaller bugs 2014-11-28 01:39:56 +01:00
.gitignore add missing makefile 2013-11-28 11:09:47 +01:00
debug.gdb improved some targets of the Makefiles used for debugging and testing 2014-11-28 01:49:03 +01:00
Doxyfile remove typos 2014-08-10 00:39:51 +02:00
link.ld remove obsolete line 2013-11-12 21:35:25 +01:00
Makefile.example add crosscompile prefix to environment variable GDB 2014-12-02 23:04:54 +01:00
Makefile.inc add the "smallest" HelloWorld of the world 2013-11-08 17:22:37 +01:00
README.md add description of stage5 2014-11-30 09:05:19 +01:00

eduOS - A teaching operating system

Introduction

eduOS is a Unix-like computer operating system based on a monolithic architecture for educational purposes. It is derived from following tutorials and software distributions.

  1. bkerndev - Bran's Kernel Development Tutorial

    The first steps to realize eduOS based on Bran's Kernel Development Tutorial (http://www.osdever.net/tutorials/view/brans-kernel-development-tutorial). In particular, the initialization of GDT, IDT and the interrupt handlers are derived from this tutorial.

  2. kprintf, umoddu3, udivdi3, qdivrem, divdi3, lshrdi3, moddi3, strtol, strtoul, ucmpdi2

    This software contains code derived from material licensed to the University of California by American Telephone and Telegraph Co. or Unix System Laboratories, Inc. and are reproduced herein with the permission of UNIX System Laboratories, Inc.

Requirements of eduOS

  • Currently, eduOS supports only x86-based architectures.
  • Following command line tools have to be installed: make, gcc, binutil, git, qemu, nams, gdb
  • The test PC has to use grub as bootloader.

Building eduOS

  1. Copy Makefile.example to Makefile and edit this Makefile to meet your individual convenience.
  2. Copy include/eduos/config.h.example to include/eduos/config.h and edit this config file to meet your individual convenience.
  3. Build kernel with "make"

Start eduOS via qemu

  1. Install qemu to emulate an x86 architecture
  2. Start emulator with "make qemu"

Boot eduOS via grub

  1. Copy eduos.elf as eduos.bin into the directory /boot. (cp eduos.elf /boot/eduos.bin)
  2. Create a boot entry in the grub menu. This depends on the version of grub, which is used by the installed Linux system. For instance, we added following lines to /boot/grub/grub.cfg:
   ### BEGIN /etc/grub.d/40_custom ###
   # This file provides an easy way to add custom menu entries.  Simply type the
   # menu entries you want to add after this comment.  Be careful not to change
   # the 'exec tail' line above.
   menuentry "Boot eduOS!" {
          multiboot       /boot/eduos.bin
          boot
   }

Overview of all branches

  1. stage0 - Smallest HelloWorld of the World

    Description of loading a minimal 32bit kernel

  2. stage1 - Non-preemptive multitasking

    Introduction into a simple form of multitasking, where no interrupts are required.

  3. stage2 - Synchronisation primitives

    Description of basic synchronization primitives

  4. stage3 - Preemptive multitasking

    Introduction into preemptive multitasking and interrupt handling

  5. stage4 - Support of user-level tasks

    Add support of user-level tasks with an small interface for basic system calls

  6. stage5 - Enabling paging

    Add support of paging. All tasks share the same page directory. => User-level triggers a page fault.

  1. http://www.gnu.org/software/grub/manual/multiboot/
  2. http://www.osdever.net/tutorials/view/brans-kernel-development-tutorial
  3. http://www.jamesmolloy.co.uk/tutorial_html/index.html
  4. http://techblog.lankes.org/tutorials/
  5. http://www.os.rwth-aachen.de