Merge pull request #231283 from nikstur/filesystems-erofs

nixos/filesystems: init erofs

nixos/modules/module-list.nix

@@ -1374,6 +1374,7 @@
   ./tasks/filesystems/cifs.nix
   ./tasks/filesystems/ecryptfs.nix
   ./tasks/filesystems/envfs.nix
+  ./tasks/filesystems/erofs.nix
   ./tasks/filesystems/exfat.nix
   ./tasks/filesystems/ext.nix
   ./tasks/filesystems/f2fs.nix

nixos/modules/system/boot/stage-1-init.sh

@@ -293,6 +293,9 @@ checkFS() {
     # Skip fsck for inherently readonly filesystems.
     if [ "$fsType" = squashfs ]; then return 0; fi
 
+    # Skip fsck.erofs because it is still experimental.
+    if [ "$fsType" = erofs ]; then return 0; fi
+
     # If we couldn't figure out the FS type, then skip fsck.
     if [ "$fsType" = auto ]; then
         echo 'cannot check filesystem with type "auto"!'

nixos/modules/tasks/filesystems/erofs.nix

@@ -0,0 +1,21 @@
+{ config, lib, pkgs, ... }:
+
+let
+
+  inInitrd = lib.any (fs: fs == "erofs") config.boot.initrd.supportedFilesystems;
+  inSystem = lib.any (fs: fs == "erofs") config.boot.supportedFilesystems;
+
+in
+
+{
+  config = lib.mkIf (inInitrd || inSystem) {
+
+    system.fsPackages = [ pkgs.erofs-utils ];
+
+    boot.initrd.availableKernelModules = lib.mkIf inInitrd [ "erofs" ];
+
+    # fsck.erofs is currently experimental and should not be run as a
+    # privileged user. Thus, it is not included in the initrd.
+
+  };
+}

nixos/tests/non-default-filesystems.nix

@@ -1,6 +1,14 @@
-import ./make-test-python.nix ({ lib, pkgs, ... }:
+{ system ? builtins.currentSystem
+, config ? { }
+, pkgs ? import ../.. { inherit system config; }
+}:
+
+with import ../lib/testing-python.nix { inherit system pkgs; };
+with pkgs.lib;
 {
-  name = "non-default-filesystems";
+  btrfs = makeTest
+    {
+      name = "non-default-filesystems-btrfs";
 
       nodes.machine =
         { config, pkgs, lib, ... }:
@@ -52,4 +60,47 @@ import ./make-test-python.nix ({ lib, pkgs, ... }:
           machine.succeed("grep -E '/dev/vda / btrfs rw,relatime,space_cache=v2,subvolid=[0-9]+,subvol=/root 0 0' /proc/mounts")
           machine.succeed("grep -E '/dev/vda /home btrfs rw,relatime,space_cache=v2,subvolid=[0-9]+,subvol=/home 0 0' /proc/mounts")
       '';
-})
+    };
+
+  erofs =
+    let
+      fsImage = "/tmp/non-default-filesystem.img";
+    in
+    makeTest {
+      name = "non-default-filesystems-erofs";
+
+      nodes.machine = _: {
+        virtualisation.qemu.drives = [{
+          name = "non-default-filesystem";
+          file = fsImage;
+        }];
+
+        virtualisation.fileSystems."/non-default" = {
+          device = "/dev/vdb";
+          fsType = "erofs";
+          neededForBoot = true;
+        };
+      };
+
+      testScript = ''
+        import subprocess
+        import tempfile
+
+        with tempfile.TemporaryDirectory() as tmp_dir:
+          with open(f"{tmp_dir}/filesystem", "w") as f:
+              f.write("erofs")
+
+          subprocess.run([
+            "${pkgs.erofs-utils}/bin/mkfs.erofs",
+            "${fsImage}",
+            tmp_dir,
+          ])
+
+        machine.start()
+        machine.wait_for_unit("default.target")
+
+        file_contents = machine.succeed("cat /non-default/filesystem")
+        assert "erofs" in file_contents
+      '';
+    };
+}