nixos/filesystems: make supportedFilesystems an attrset

this lets us *dis*able filesystem explicitly, as is required by e.g. the
zfs-less installer images. currently that specifically is only easily
possible by adding an overlay that stubs out `zfs`, with the obvious
side-effect of also removing tooling that could run without the kernel
module loaded.

2 files changed, 4 insertions, 20 deletions

diff --git a/nixos/modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix b/nixos/modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix
index 9d09cdbe0206d..fc3cb08bdbbb3 100644
--- a/nixos/modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix
+++ b/nixos/modules/installer/cd-dvd/installation-cd-minimal-new-kernel-no-zfs.nix
@@ -1,15 +1,7 @@
-{ pkgs, ... }:
+{ lib, ... }:
 
 {
   imports = [ ./installation-cd-minimal-new-kernel.nix ];
 
-  # Makes `availableOn` fail for zfs, see <nixos/modules/profiles/base.nix>.
-  # This is a workaround since we cannot remove the `"zfs"` string from `supportedFilesystems`.
-  # The proper fix would be to make `supportedFilesystems` an attrset with true/false which we
-  # could then `lib.mkForce false`
-  nixpkgs.overlays = [(final: super: {
-    zfs = super.zfs.overrideAttrs(_: {
-      meta.platforms = [];
-    });
-  })];
+  boot.supportedFilesystems.zfs = lib.mkForce false;
 }
diff --git a/nixos/modules/installer/sd-card/sd-image-aarch64-new-kernel-no-zfs-installer.nix b/nixos/modules/installer/sd-card/sd-image-aarch64-new-kernel-no-zfs-installer.nix
index 0e50559602945..da5410057887e 100644
--- a/nixos/modules/installer/sd-card/sd-image-aarch64-new-kernel-no-zfs-installer.nix
+++ b/nixos/modules/installer/sd-card/sd-image-aarch64-new-kernel-no-zfs-installer.nix
@@ -1,15 +1,7 @@
-{ pkgs, ... }:
+{ lib, ... }:
 
 {
   imports = [ ./sd-image-aarch64-new-kernel-installer.nix ];
 
-  # Makes `availableOn` fail for zfs, see <nixos/modules/profiles/base.nix>.
-  # This is a workaround since we cannot remove the `"zfs"` string from `supportedFilesystems`.
-  # The proper fix would be to make `supportedFilesystems` an attrset with true/false which we
-  # could then `lib.mkForce false`
-  nixpkgs.overlays = [(final: super: {
-    zfs = super.zfs.overrideAttrs(_: {
-      meta.platforms = [];
-    });
-  })];
+  boot.supportedFilesystems.zfs = lib.mkForce false;
 }