From 379831e348e0c7b07a47945cbd9e95e0bef79caf Mon Sep 17 00:00:00 2001
From: William <baduhai@proton.me>
Date: Sun, 18 Feb 2024 21:26:36 -0300
Subject: [PATCH] io is now ephermal

---
 hosts/desktops/io/default.nix                |  2 +-
 hosts/desktops/io/ephermal.nix               | 44 +++++++++++++
 hosts/desktops/io/hardware-configuration.nix | 69 +++++++++++++-------
 3 files changed, 89 insertions(+), 26 deletions(-)
 create mode 100644 hosts/desktops/io/ephermal.nix

diff --git a/hosts/desktops/io/default.nix b/hosts/desktops/io/default.nix
index 704aaf0..3b3c6ee 100644
--- a/hosts/desktops/io/default.nix
+++ b/hosts/desktops/io/default.nix
@@ -1,5 +1,5 @@
 { ... }:
 
 {
-  imports = [ ./hardware-configuration.nix ];
+  imports = [ ./ephermal.nix ./hardware-configuration.nix ];
 }
diff --git a/hosts/desktops/io/ephermal.nix b/hosts/desktops/io/ephermal.nix
new file mode 100644
index 0000000..7bfc484
--- /dev/null
+++ b/hosts/desktops/io/ephermal.nix
@@ -0,0 +1,44 @@
+{ config, lib, pkgs, ... }:
+ 
+{
+  boot.initrd.systemd.services.recreate-root = {
+    description = "Rolling over and creating new filesystem root";
+    requires = [ "initrd-root-device.target" ];
+    after = [ "local-fs-pre.target" "initrd-root-device.target" ];
+    requiredBy = [ "initrd-root-fs.target" ];
+    before = [ "sysroot.mount" ];
+    unitConfig = {
+      AssertPathExists = "/etc/initrd-release";
+      DefaultDependencies = false;
+    };
+    serviceConfig = {
+      Type = "oneshot";
+      RemainAfterExit = true;
+    };
+    script = ''
+      mkdir /btrfs_tmp
+    mount /dev/disk/by-uuid/ef1916a9-e15c-450e-8100-4b2af9f6e1a5 /btrfs_tmp
+ 
+      if [[ -e /btrfs_tmp/@root ]]; then
+        mkdir -p /btrfs_tmp/old_roots
+        timestamp=$(date --date="@$(stat -c %Y /btrfs_tmp/@root)" "+%Y-%m-%-d_%H:%M:%S")
+        mv /btrfs_tmp/@root "/btrfs_tmp/old_roots/$timestamp"
+      fi
+ 
+      delete_subvolume_recursively() {
+        IFS=$'\n'
+        for i in $(btrfs subvolume list -o "$1" | cut -f 9- -d ' '); do
+           delete_subvolume_recursively "/btrfs_tmp/$i"
+        done
+        btrfs subvolume delete "$1"
+      }
+ 
+      for i in $(find /btrfs_tmp/old_roots/ -maxdepth 1 -mtime +30); do
+        delete_subvolume_recursively "$i"
+      done
+ 
+      btrfs subvolume create /btrfs_tmp/@root
+      umount /btrfs_tmp
+    '';
+  };
+}
\ No newline at end of file
diff --git a/hosts/desktops/io/hardware-configuration.nix b/hosts/desktops/io/hardware-configuration.nix
index c2497a1..d1939c1 100644
--- a/hosts/desktops/io/hardware-configuration.nix
+++ b/hosts/desktops/io/hardware-configuration.nix
@@ -1,40 +1,59 @@
-# Do not modify this file!  It was generated by ‘nixos-generate-config’
-# and may be overwritten by future invocations.  Please make changes
-# to /etc/nixos/configuration.nix instead.
-{ config, pkgs, lib, modulesPath, ... }:
+{ config, lib, modulesPath, ... }:
 
 {
   imports = [ (modulesPath + "/installer/scan/not-detected.nix") ];
 
-  boot.initrd.availableKernelModules =
-    [ "xhci_pci" "ahci" "usb_storage" "sd_mod" "sdhci_pci" ];
-  boot.initrd.kernelModules = [ ];
-  boot.kernelModules = [ "kvm-intel" ];
-  boot.extraModulePackages = [ ];
-
-  fileSystems."/" = {
-    device = "/dev/disk/by-uuid/2321ee32-a952-4a4b-bba0-bb25f616a4a5";
-    fsType = "ext4";
+  boot = {
+    initrd = {
+      availableKernelModules =
+        [ "xhci_pci" "ahci" "usb_storage" "sd_mod" "sdhci_pci" ];
+      luks.devices."cryptroot".device =
+        "/dev/disk/by-uuid/37c930c5-2b31-4d18-a1c4-7f13e0412656";
+    };
+    kernelModules = [ "kvm-intel" ];
   };
 
-  boot.initrd.luks.devices."luks-008bb7cb-917c-4dda-93fe-542c2285bafb".device =
-    "/dev/disk/by-uuid/008bb7cb-917c-4dda-93fe-542c2285bafb";
-
-  fileSystems."/boot/efi" = {
-    device = "/dev/disk/by-uuid/36B4-C473";
-    fsType = "vfat";
+  fileSystems = {
+    "/" = {
+      device = "/dev/disk/by_uuid/ef1916a9-e15c-450e-8100-4b2af9f6e1a5";
+      fsType = "btrfs";
+      options = [ "subvol=@root" "noatime" "compress=zstd" ];
+    };
+    "/home" = {
+      device = "/dev/disk/by_uuid/ef1916a9-e15c-450e-8100-4b2af9f6e1a5";
+      fsType = "btrfs";
+      options = [ "subvol=@home" "noatime" "compress=zstd" ];
+    };
+    "/boot/efi" = {
+      device = "/dev/disk/by-uuid/36B4-C473";
+      fsType = "vfat";
+      options = [ "noatime" "fmask=0077" "dmask=0077" ];
+    };
+    "/nix" = {
+      device = "/dev/disk/by_uuid/ef1916a9-e15c-450e-8100-4b2af9f6e1a5";
+      fsType = "btrfs";
+      options = [ "subvol=@nix" "noatime" "compress=zstd" ];
+    };
+    "/persistent" = {
+      device = "/dev/disk/by_uuid/ef1916a9-e15c-450e-8100-4b2af9f6e1a5";
+      fsType = "btrfs";
+      options = [ "subvol=@persistent" "noatime" "compress=zstd" ];
+    };
+    "/swap" = {
+      device = "/dev/disk/by_uuid/ef1916a9-e15c-450e-8100-4b2af9f6e1a5";
+      fsType = "btrfs";
+      options = [ "subvol=@swap" "noatime" ];
+    };
   };
 
-  swapDevices = [ ];
+  swapDevices = [{ "/swap/swapfile"; }];
 
-  # Enables DHCP on each ethernet and wireless interface. In case of scripted networking
-  # (the default) this is the recommended approach. When using systemd-networkd it's
-  # still possible to use this option, but it's recommended to use it in conjunction
-  # with explicit per-interface declarations with `networking.interfaces.<interface>.useDHCP`.
   networking.useDHCP = lib.mkDefault true;
-  # networking.interfaces.wlp0s20f3.useDHCP = lib.mkDefault true;
+
+  nixpkgs.hostPlatform = lib.mkDefault "x86_64";
 
   powerManagement.cpuFreqGovernor = lib.mkDefault "powersave";
+
   hardware.cpu.intel.updateMicrocode =
     lib.mkDefault config.hardware.enableRedistributableFirmware;
 }