fs: rename "service" option to "unit" option

modules/fs.nix

@@ -3,6 +3,8 @@ with lib;
 let
   cfg = config.sane.fs;
 
+  serviceNameFor = path: "ensure-${utils.escapeSystemdPath path}";
+
   # sane.fs."<path>" top-level options
   fsEntry = types.submodule ({ name, ...}: let
     parent = parentDir name;
@@ -19,19 +21,21 @@ let
       };
       depends = mkOption {
         type = types.listOf types.str;
-        description = "list of systemd services needed to be run before this service";
+        description = "list of systemd units needed to be run before this service";
         default = [];
       };
-      service = mkOption {
+      unit = mkOption {
         type = types.str;
-        description = "name of the systemd service which ensures this entry";
-        default = "ensure-${utils.escapeSystemdPath name}";
+        description = "name of the systemd unit which ensures this entry";
       };
     };
     config = {
       # we put this here instead of as a `default` to ensure that users who specify additional
       # dependencies still get a dep on the parent (unless they assign with `mkForce`).
-      depends = if has-parent then [ "${parent-cfg.service}.service" ] else [];
+      depends = if has-parent then [ parent-cfg.unit ] else [];
+      # this option for the benefit of being read by users (for now).
+      # making it read-only simplifies our impl.
+      unit = (serviceNameFor name) + ".service";
     };
   });
   # sane.fs."<path>".dir sub-options
@@ -52,7 +56,7 @@ let
 
   # given a fsEntry definition, output the `config` attrs it generates.
   mkFsConfig = path: opt: {
-    systemd.services."${opt.service}" = {
+    systemd.services."${serviceNameFor path}" = {
       description = "prepare ${path}";
       script = ensure-dir-script;
       scriptArgs = "${path} ${opt.dir.user} ${opt.dir.group} ${opt.dir.mode}";

modules/impermanence/crypt.nix

@@ -30,11 +30,6 @@ let
   };
 in lib.mkIf config.sane.impermanence.enable
 {
-  # the crypt store requires keys before being mounted
-  sane.fs."${store.device}".depends = [
-    "prepareEncryptedClearedOnBoot.service"
-  ];
-
   # declare our backing storage
   sane.fs."${store.underlying.path}".dir = {};
 
@@ -52,9 +47,9 @@ in lib.mkIf config.sane.impermanence.enable
 
     # we need the key directory to be created, and the backing directory to exist
     after = [
-      (config.sane.fs."${store.underlying.path}".service + ".service")
+      config.sane.fs."${store.underlying.path}".unit
       # TODO: "${parentDir store.device}"
-      (config.sane.fs."/mnt/impermanence/crypt".service + ".service")
+      config.sane.fs."/mnt/impermanence/crypt".unit
     ];
     wants = after;
 
@@ -63,7 +58,6 @@ in lib.mkIf config.sane.impermanence.enable
     wantedBy = before;
   };
 
-
   fileSystems."${store.device}" = {
     device = store.underlying.path;
     fsType = "fuse.gocryptfs";

modules/impermanence/default.nix

@@ -124,11 +124,11 @@ in
         let
           # systemd creates <path>.mount services for every fileSystems entry.
           # <path> gets escaped as part of that: this code tries to guess that escaped name here.
-          mount-service = utils.escapeSystemdPath opt.directory;
+          mount-unit = "${utils.escapeSystemdPath opt.directory}.mount";
           backing-path = concatPaths [ opt.store opt.directory ];
 
-          dir-service = config.sane.fs."${opt.directory}".service;
-          backing-service = config.sane.fs."${backing-path}".service;
+          dir-unit = config.sane.fs."${opt.directory}".unit;
+          backing-unit = config.sane.fs."${backing-path}".unit;
           # pass through the perm/mode overrides
           dir-opts = {
             user = lib.mkIf (opt.user != null) opt.user;
@@ -145,17 +145,18 @@ in
             options = [
               "bind"
               # "x-systemd.requires=${backing-mount}.mount"  # this should be implicit
-              "x-systemd.after=${backing-service}.service"
-              "x-systemd.after=${dir-service}.service"
+              "x-systemd.after=${backing-unit}"
+              "x-systemd.after=${dir-unit}"
               # `wants` doesn't seem to make it to the service file here :-(
-              # "x-systemd.wants=${backing-service}"
-              # "x-systemd.wants=${dir-service}"
+              # "x-systemd.wants=${backing-unit}"
+              # "x-systemd.wants=${dir-unit}"
             ];
             # fsType = "bind";
             noCheck = true;
           };
-          systemd.services."${backing-service}".wantedBy = [ "${mount-service}.mount" ];
-          systemd.services."${dir-service}".wantedBy = [ "${mount-service}.mount" ];
+          # mounting <opt.directory> must happen after the backing directory is created *and* the mountpt directory is created.
+          systemd.units."${backing-unit}".wantedBy = [ mount-unit ];
+          systemd.units."${dir-unit}".wantedBy = [ mount-unit ];
 
         };
         cfgs = builtins.map cfgFor ingested-dirs;