From 9d89ca0c03a669a81f4e98aa6fbf2606cea15ff7 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Fri, 9 Mar 2012 16:17:37 +0000
Subject: [PATCH] * Modularise vfat support.  Also add fsck.vfat to the initrd.
  This   prevents errors when booting from VFAT (e.g. an ISO image converted  
 using unetbootin).

svn path=/nixos/trunk/; revision=32956
---
 modules/installer/cd-dvd/iso-image.nix |  5 +++++
 modules/module-list.nix                |  1 +
 modules/profiles/all-hardware.nix      |  4 ----
 modules/profiles/base.nix              |  2 +-
 modules/tasks/filesystems/vfat.nix     | 25 +++++++++++++++++++++++++
 5 files changed, 32 insertions(+), 5 deletions(-)
 create mode 100644 modules/tasks/filesystems/vfat.nix

diff --git a/modules/installer/cd-dvd/iso-image.nix b/modules/installer/cd-dvd/iso-image.nix
index 0a2f76c919c..7cc08315d01 100644
--- a/modules/installer/cd-dvd/iso-image.nix
+++ b/modules/installer/cd-dvd/iso-image.nix
@@ -259,4 +259,9 @@ in
       touch /etc/NIXOS
       ${config.environment.nix}/bin/nix-env -p /nix/var/nix/profiles/system --set /var/run/current-system
     '';
+
+  # Add vfat support to the initrd to enable people to copy the
+  # contents of the CD to a bootable USB stick.
+  boot.initrd.supportedFilesystems = [ "vfat" ];
+    
 }
diff --git a/modules/module-list.nix b/modules/module-list.nix
index 5a1459f5226..b69295a89da 100644
--- a/modules/module-list.nix
+++ b/modules/module-list.nix
@@ -203,6 +203,7 @@
   ./tasks/filesystems/ext.nix
   ./tasks/filesystems/nfs.nix
   ./tasks/filesystems/reiserfs.nix
+  ./tasks/filesystems/vfat.nix
   ./tasks/kbd.nix
   ./tasks/lvm.nix
   ./tasks/network-interfaces.nix
diff --git a/modules/profiles/all-hardware.nix b/modules/profiles/all-hardware.nix
index 8b894fa4df0..041948aa462 100644
--- a/modules/profiles/all-hardware.nix
+++ b/modules/profiles/all-hardware.nix
@@ -41,10 +41,6 @@
 
       # Virtio (QEMU, KVM etc.) support.
       "virtio_net" "virtio_pci" "virtio_blk" "virtio_balloon" "virtio_console"
-
-      # Add vfat to enable people to copy the contents of the CD to a
-      # bootable USB stick.
-      "vfat" "nls_cp437" "nls_iso8859-1"
     ];
 
   boot.initrd.kernelModules =
diff --git a/modules/profiles/base.nix b/modules/profiles/base.nix
index d6412e09a5f..75a58f8568a 100644
--- a/modules/profiles/base.nix
+++ b/modules/profiles/base.nix
@@ -51,6 +51,6 @@
   ];
 
   # Include support for various filesystems.
-  boot.supportedFilesystems = [ "btrfs" "reiserfs" ];
+  boot.supportedFilesystems = [ "btrfs" "reiserfs" "vfat" ];
 
 }
diff --git a/modules/tasks/filesystems/vfat.nix b/modules/tasks/filesystems/vfat.nix
new file mode 100644
index 00000000000..5ca72f142b7
--- /dev/null
+++ b/modules/tasks/filesystems/vfat.nix
@@ -0,0 +1,25 @@
+{ config, pkgs, ... }:
+
+with pkgs.lib;
+
+let
+
+  inInitrd = any (fs: fs == "vfat") config.boot.initrd.supportedFilesystems;
+
+in
+
+{
+  config = mkIf (any (fs: fs == "vfat") config.boot.supportedFilesystems) {
+
+    system.fsPackages = [ pkgs.dosfstools ];
+
+    boot.initrd.kernelModules = mkIf inInitrd [ "vfat" "nls_cp437" "nls_iso8859-1" ];
+
+    boot.initrd.extraUtilsCommands = mkIf inInitrd
+      ''
+        cp -v ${pkgs.dosfstools}/sbin/dosfsck $out/bin
+        ln -sv dosfsck $out/bin/fsck.vfat
+      '';
+
+  };
+}