JasOS Kernel

A simple, educational ARM-based operating system kernel running on QEMU. This is a text-based UART-only version that includes basic OS components.

Features

• Memory Management

  • Dynamic memory allocation and deallocation
  • Block splitting and coalescing
  • Memory usage visualization

• Process Management

  • Simple process creation and termination
  • Round-robin scheduling
  • Process states (Ready, Running, Blocked, Terminated)
  • CPU usage tracking

• File System

  • In-memory tree-like structure
  • Support for files and directories
  • Commands: ls, cd, mkdir, touch, cat, edit, rm

• System Monitor

  • Interactive visualization of system resources
  • Memory usage display
  • Process activity display
  • CPU usage monitoring

Building

To build JasOS, you'll need an ARM cross-compiler (arm-none-eabi-gcc) and QEMU.

# Build the kernel
make

# Run the kernel
make run

Available Commands

Shell Commands

• help - Show available commands
• version - Show kernel version
• clear - Clear screen
• info - Show system info
• exit - Quit (halt system)

File System Commands

• ls - List directory contents
• cd <dir> - Change directory
• pwd - Print working directory
• mkdir <name> - Create directory
• touch <name> - Create empty file
• cat <file> - Display file contents
• edit <file> - Edit file
• rm <name> - Remove file or directory

Process Management Commands

• ps - List processes
• testproc - Create a test process
• kill <pid> - Terminate a process

Memory Management Commands

• memdump - Show memory statistics

System Monitor

• monitor - Start the system monitor

System Monitor Commands

When in the system monitor mode, the following commands are available:

• overview - Show system overview
• mem - Show detailed memory information
• proc - Show detailed process information
• help - Show help screen
• exit - Exit monitor and return to shell

Architecture

JasOS is organized into several components:

1. Core Kernel - Handles initialization and shell interface
2. Memory Manager - Manages heap and allocation
3. Process Manager - Handles process creation and scheduling
4. File System - Manages file and directory operations
5. System Monitor - Provides visualization of system resources

Using QEMU

To exit QEMU, press Ctrl+A, then X.

License

This project is for educational purposes only.