Update QEMU.md

QEMU.md

@@ -1,14 +1,93 @@
 ## PLAIN QEMU WITHOUT LIBVIRT
-#### DRAFT
+
 Passthrough can be done with plain qemu without using libvirt. \
 The general idea of using plain qemu is to avoid managing libvirt configurations and rather use a single script.. \
-So, how can this be achieved? \
-The script should be written in this order to achieve the same thing which is currently done by libvirt.. \
+You'd still need libvirt daemon running because we're using virsh command. \
+
+Create disk image with QEMU.
+```sh
+qemu-img create -f raw Disk.img 256G
+```
+
+The script should be run as superuser. \
+It's possible to get it working as user but it's tricky to setup. \
+Also, it should be run from TTY..
 
 ```sh
-# SCRIPT TO RUN BEFORE VM LAUNCH - same as libvirt begin
+#!/bin/sh
+
+# Should be run before VM starts
+function init_vm() {
+	# Stop display manager (if any exists)
+	# rc-service xdm stop
+	# systemctl stop display-manager 
+	
+	# Unbind EFI-framebuffer
+	echo efi-framebuffer.0 > /sys/bus/platform/drivers/efi-framebuffer/unbind
+	
+	# Unload GPU modules
+	modprobe -r nvidia_drm nvidia_modeset nvidia_uvm nvidia 
+	# modprobe -r amdgpu 
+	
+	# Detach GPU from host
+	virsh nodedev-detach pci_0000_01_00_0
+	virsh nodedev-detach pci_0000_01_00_1
+	
+	# Load vfio modules
+	modprobe vfio-pci
+}
+
+# Start VM
+function start_vm() {
+	qemu-system-x86_64 \
+		-nodefaults \
+		-enable-kvm \
+		-machine kernel_irqchip=on \
+		-cpu host,kvm=off,hv_vendor_id=nil \
+		-m 4G \
+		-name "Guix" \
+		-smp cores=2 \
+		-drive file=/home/qaidvoid/VM/Disk.img,if=virtio,format=raw \
+		-drive file=/home/qaidvoid/Downloads/guix-system-install-1.2.0.x86_64-linux.iso,media=cdrom \
+		-serial none \
+		-net nic \
+		-net user \
+		-vga none \
+		-device vfio-pci,host=01:00.0,x-vga=on,multifunction=on \
+		-device vfio-pci,host=01:00.1 \
+		-object input-linux,id=mouse1,evdev=/dev/input/by-id/usb-PixArt_HP_USB_Optical_Mouse-event-mouse \
+		-object input-linux,id=kbd1,evdev=/dev/input/by-id/usb-Chicony_USB_Keyboard-event-kbd,grab_all=on,repeat=on \
+		-device virtio-keyboard \
+		-device virtio-mouse
+}
+
+# Should be run on VM shutdown
+function stop_vm() {
+	# Unload VFIO modules
+	modprobe -r vfio-pci
+	
+	# Attach GPU to host
+	virsh nodedev-reattach pci_0000_01_00_0
+	virsh nodedev-reattach pci_0000_01_00_1
+	
+	# Bind EFI framebuffer to host
+	echo "efi-framebuffer.0" > /sys/bus/platform/drivers/efi-framebuffer/bind
+	
+	# Load GPU modules
+	modprobe nvidia_drm
+	modprobe nvidia_modeset
+	modprobe nvidia_uvm
+	modprobe nvidia
+	# modprobe amdgpu
+	
+	# Restart Display Manager? Doesn't seem to work quite well
+	# rc-service xdm start
+	# systemctl start display-manager
+  reboot
+}
 
-# LAUNCH VM HERE USING QEMU
+init_vm
+start_vm
+stop_vm
 
-# SCRIPT TO RUN ON VM END - same as libvirt end
 ```