From ce6e0f69af06485256ffb3e802e9284582ef5cb3 Mon Sep 17 00:00:00 2001
From: Julien Malka <julien@malka.sh>
Date: Sat, 26 Apr 2025 12:56:41 +0200
Subject: [PATCH] chore: move gustave to ext4

---
 machines/gustave/disko.nix    | 80 +++++++++++++++++++++++------------
 machines/gustave/hardware.nix | 38 ++++++-----------
 2 files changed, 65 insertions(+), 53 deletions(-)

diff --git a/machines/gustave/disko.nix b/machines/gustave/disko.nix
index 8be9924..ebe567d 100644
--- a/machines/gustave/disko.nix
+++ b/machines/gustave/disko.nix
@@ -1,17 +1,18 @@
 {
   devices = {
     disk = {
-      sda = {
+      main = {
         type = "disk";
-        device = "/dev/sda";
+        device = "/dev/sdb";
         content = {
           type = "gpt";
           partitions = {
+            boot = {
+              size = "1M";
+              type = "EF02";
+            };
             ESP = {
-              priority = 1;
-              name = "ESP";
-              start = "1M";
-              end = "128M";
+              size = "512M";
               type = "EF00";
               content = {
                 type = "filesystem";
@@ -19,35 +20,60 @@
                 mountpoint = "/boot";
               };
             };
+            swap = {
+              size = "16G";
+              content = {
+                type = "swap";
+                discardPolicy = "both";
+              };
+            };
             root = {
               size = "100%";
               content = {
-                type = "btrfs";
-                extraArgs = [ "-f" ]; # Override existing partition
-                # Subvolumes must set a mountpoint in order to be mounted,
-                # unless their parent is mounted
-                subvolumes = {
-                  # Subvolume name is different from mountpoint
-                  "/root" = {
-                    mountpoint = "/";
-                  };
-                  # Subvolume name is the same as the mountpoint
-                  "/persistent" = {
-                    mountpoint = "/persistent";
-                  };
-                  "/nix" = {
-                    mountOptions = [
-                      "compress=zstd"
-                      "noatime"
-                    ];
-                    mountpoint = "/nix";
-                  };
-                };
+                type = "lvm_pv";
+                vg = "mainpool";
               };
             };
           };
         };
       };
     };
+    lvm_vg = {
+      mainpool = {
+        type = "lvm_vg";
+        lvs = {
+          root = {
+            size = "100G";
+            pool = "mainpool";
+            content = {
+              type = "filesystem";
+              format = "ext4";
+              mountpoint = "/";
+              mountOptions = [ "defaults" ];
+            };
+          };
+          persistent = {
+            size = "1500G";
+            pool = "mainpool";
+            content = {
+              type = "filesystem";
+              format = "ext4";
+              mountpoint = "/persistent";
+              mountOptions = [ "defaults" ];
+            };
+          };
+
+          store = {
+            size = "200G";
+            pool = "mainpool";
+            content = {
+              type = "filesystem";
+              format = "ext4";
+              mountpoint = "/nix";
+            };
+          };
+        };
+      };
+    };
   };
 }
diff --git a/machines/gustave/hardware.nix b/machines/gustave/hardware.nix
index a383bfe..dd6472f 100644
--- a/machines/gustave/hardware.nix
+++ b/machines/gustave/hardware.nix
@@ -1,4 +1,9 @@
-{ lib, modulesPath, ... }:
+{
+  lib,
+  modulesPath,
+  pkgs,
+  ...
+}:
 
 {
   imports = [ (modulesPath + "/profiles/qemu-guest.nix") ];
@@ -15,33 +20,14 @@
   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
+  boot.initrd.postDeviceCommands = ''
+    lvm lvremove --force /dev/mainpool/root || :
+    yes | lvm lvcreate --size 100G --name root mainpool
+    ${pkgs.e2fsprogs}/bin/mkfs.ext4 /dev/mainpool/root
   '';
 
+  fileSystems."/persistent".neededForBoot = lib.mkForce true;
+
   networking.useDHCP = lib.mkDefault true;
 
   nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";