From 0c37b520334f006b354d5035fc0f01944868fad9 Mon Sep 17 00:00:00 2001
From: rnhmjoj <rnhmjoj@inventati.org>
Date: Mon, 26 Aug 2024 13:16:47 +0200
Subject: [PATCH] backup: fix repository not being unmounted

This mounts the backup in a detached mount namespace, the mountpoint is
automatically unmounted when the process exits.
---
 jobs.nix | 17 ++++-------------
 1 file changed, 4 insertions(+), 13 deletions(-)

diff --git a/jobs.nix b/jobs.nix
index 6073223..b131a4e 100644
--- a/jobs.nix
+++ b/jobs.nix
@@ -56,14 +56,6 @@ with lib;
     '';
   };
 
-  systemd.mounts = lib.singleton
-    {
-      description = "backup volume";
-      what   = "/dev/mapper/backup-maxwell";
-      where  = "/mnt/backup";
-      partOf = [ "backup.service" ];
-    };
-
   systemd.services.backup =
   let
     saved = pkgs.writeText "backup-saved" ''
@@ -82,25 +74,24 @@ with lib;
 
   in {
     description = "system backup";
-    after       = [ "mnt-backup.mount" ];
-    requires    = [ "mnt-backup.mount" ];
     startAt     = "*-*-* 03:00";  # every day at 3:00
     onFailure   = [ "notify-failed@backup.service" ];
 
     serviceConfig = {
       Type = "oneshot";
       PrivateTmp = true;
+      PrivateMounts = true;
       LimitNOFILE = 65536;
     };
 
     environment.BUP_DIR = "/mnt/backup";
-    path = with pkgs; [ bup git nfs-utils sudo gzip postgresql ];
+    path = with pkgs; [ bup git util-linux sudo gzip postgresql ];
 
     script = ''
       # mount repository
-      mkdir -p "$BUP_DIR"
+      mount -m -L backup "$BUP_DIR"
 
-      # init backup
+      # init backup, if empty
       ! test -e $BUP_DIR/bupindex && bup init
 
       # build indices and save