Don't include ntfs-3g by default

Issue #7117.

nixos/modules/installer/cd-dvd/installation-cd-base.nix

@@ -45,9 +45,6 @@ with lib;
   # Get a console as soon as the initrd loads fbcon on EFI boot.
   boot.initrd.kernelModules = [ "fbcon" ];
 
-  # Add support for cow filesystems and their utilities
-  boot.supportedFilesystems = [ "zfs" "btrfs" ];
-
   # Configure host id for ZFS to work
   networking.hostId = "8425e349";
 

nixos/modules/module-list.nix

@@ -430,6 +430,7 @@
   ./tasks/filesystems/f2fs.nix
   ./tasks/filesystems/jfs.nix
   ./tasks/filesystems/nfs.nix
+  ./tasks/filesystems/ntfs.nix
   ./tasks/filesystems/reiserfs.nix
   ./tasks/filesystems/unionfs-fuse.nix
   ./tasks/filesystems/vfat.nix

nixos/modules/profiles/base.nix

@@ -50,6 +50,6 @@
   ];
 
   # Include support for various filesystems.
-  boot.supportedFilesystems = [ "btrfs" "reiserfs" "vfat" "f2fs" ];
+  boot.supportedFilesystems = [ "btrfs" "reiserfs" "vfat" "f2fs" "zfs" "ntfs" ];
 
 }

nixos/modules/tasks/filesystems.nix

@@ -137,9 +137,7 @@ in
     # Add the mount helpers to the system path so that `mount' can find them.
     system.fsPackages = [ pkgs.dosfstools ];
 
-    environment.systemPackages =
-      [ pkgs.ntfs3g pkgs.fuse ]
-      ++ config.system.fsPackages;
+    environment.systemPackages = [ pkgs.fuse ] ++ config.system.fsPackages;
 
     environment.etc.fstab.text =
       let

nixos/modules/tasks/filesystems/ntfs.nix

@@ -0,0 +1,16 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+  config = mkIf (any (fs: fs == "ntfs" || fs == "ntfs-3g") config.boot.supportedFilesystems) {
+
+    system.fsPackages = [ pkgs.ntfs3g ];
+
+    boot.initrd.kernelModules = mkIf inInitrd [ "jfs" ];
+
+    boot.initrd.extraUtilsCommands = mkIf inInitrd ''
+      copy_bin_and_libs ${pkgs.jfsutils}/sbin/fsck.jfs
+    '';
+  };
+}