feat: init gustave

machines/gustave/hardware.nix

@@ -1,16 +1,46 @@
-{ config, lib, pkgs, modulesPath, ... }:
+{ lib, modulesPath, ... }:
 
 {
-  imports =
-    [
-      (modulesPath + "/profiles/qemu-guest.nix")
-    ];
+  imports = [ (modulesPath + "/profiles/qemu-guest.nix") ];
 
-  boot.initrd.availableKernelModules = [ "ata_piix" "uhci_hcd" "virtio_pci" "virtio_scsi" "sd_mod" "sr_mod" ];
+  boot.initrd.availableKernelModules = [
+    "ata_piix"
+    "uhci_hcd"
+    "virtio_pci"
+    "virtio_scsi"
+    "sd_mod"
+    "sr_mod"
+  ];
   boot.initrd.kernelModules = [ ];
   boot.kernelModules = [ ];
   boot.extraModulePackages = [ ];
 
+  fileSystems."/persistent".neededForBoot = lib.mkForce true;
+
+  boot.initrd.postDeviceCommands = lib.mkAfter ''
+    mkdir /btrfs_tmp
+    mount /dev/disk/by-partlabel/disk-sda-root /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
+  '';
 
   networking.useDHCP = lib.mkDefault true;