mosmos

Toy OS for learning purpose

Demo

Features

• x86_64 support
• Multitasking
• RTL8169 NIC driver
• Network stack (TCP, UDP, IP)
• Userland CLI application

Todos

• Run on QEMU
• Better memory/page management
• Improve TCP stack
  • Handle reordering and options
  • Window control
  • Test with various cases (e.g. pkt loss, large delay)
• SMP support
• File system
• UEFI support

mosmos image

	begin	end	size
mbr	0	0x01ff	512B
boot	0x200	0x1ffff	8KB
kernel	0x2000	0x11fff	64KB

Memory map

	begin	end	size
mbr + boot	0x00007c00	0x00009bff	8KB
kernel(initial)	0x00009c00	0x00019bff	64KB
page table for long mode	0x00079000	0x00079fff	4KB
gdt table	0x00090000	0x00090fff	4KB
intrupption vec	0x00091000	0x00092fff	8KB
kernel(relocated)	0x00101000	0x00110fff	64KB
kstack for userapp(temporary)		0x00900000
free(managed by mem lib)	0x00a00000

References

• General OS knowledge
  • はじめて読む486
  • 30日でできる! OS自作入門
  • 作って理解するOS x86系コンピュータを動かす理論と実装
  • ０から作るソフトウェア開発
  • OSDev
• RTL8169 driver
  • OSDev RTL8139
  • OSDev RTL8169
  • RTL8169 Datasheet
• 64bit/paging/context switch
  • https://github.com/drpnd/advos
• Implementation
  • https://github.com/matsud224/tinyos
  • https://github.com/Totsugekitai/minOSv2
  • https://github.com/szhou42/osdev