Update AMI generator

The EBS and S3 (instance-store) AMIs are now created from the same
image. HVM instance-store AMIs are also generated.

Disk image generation has been factored out into a function
(nixos/lib/make-disk-image.nix) that can be used to build other kinds
of images.

4 files changed, 151 insertions, 86 deletions

diff --git a/nixos/modules/virtualisation/amazon-config.nix b/nixos/modules/virtualisation/amazon-config.nix
deleted file mode 100644
index 809cdb4d108..00000000000
--- a/nixos/modules/virtualisation/amazon-config.nix
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  imports = [ <nixpkgs/nixos/modules/virtualisation/amazon-image.nix> ];
-}
diff --git a/nixos/modules/virtualisation/amazon-grow-partition.nix b/nixos/modules/virtualisation/amazon-grow-partition.nix
new file mode 100644
index 00000000000..31899fae6c0
--- /dev/null
+++ b/nixos/modules/virtualisation/amazon-grow-partition.nix
@@ -0,0 +1,47 @@
+# This module automatically grows the root partition on Amazon EC2 HVM
+# instances. This allows an instance to be created with a bigger root
+# filesystem than provided by the AMI.
+
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  growpart = pkgs.stdenv.mkDerivation {
+    name = "growpart";
+    src = pkgs.fetchurl {
+      url = "https://launchpad.net/cloud-utils/trunk/0.27/+download/cloud-utils-0.27.tar.gz";
+      sha256 = "16shlmg36lidp614km41y6qk3xccil02f5n3r4wf6d1zr5n4v8vd";
+    };
+    patches = [ ./growpart-util-linux-2.26.patch ];
+    buildPhase = ''
+      cp bin/growpart $out
+      sed -i 's|awk|gawk|' $out
+      sed -i 's|sed|gnused|' $out
+    '';
+    dontInstall = true;
+    dontPatchShebangs = true;
+  };
+
+in
+
+{
+
+  config = mkIf config.ec2.hvm {
+
+    boot.initrd.extraUtilsCommands = ''
+      copy_bin_and_libs ${pkgs.gawk}/bin/gawk
+      copy_bin_and_libs ${pkgs.gnused}/bin/sed
+      copy_bin_and_libs ${pkgs.utillinux}/sbin/sfdisk
+      cp -v ${growpart} $out/bin/growpart
+      ln -s sed $out/bin/gnused
+    '';
+
+    boot.initrd.postDeviceCommands = ''
+      [ -e /dev/xvda ] && [ -e /dev/xvda1 ] && TMPDIR=/run sh $(type -P growpart) /dev/xvda 1
+    '';
+
+  };
+
+}
diff --git a/nixos/modules/virtualisation/amazon-image.nix b/nixos/modules/virtualisation/amazon-image.nix
index 600a29f31bc..dd81c424a91 100644
--- a/nixos/modules/virtualisation/amazon-image.nix
+++ b/nixos/modules/virtualisation/amazon-image.nix
@@ -1,95 +1,28 @@
+# Configuration for Amazon EC2 instances. (Note that this file is a
+# misnomer - it should be "amazon-config.nix" or so, not
+# "amazon-image.nix", since it's used not only to build images but
+# also to reconfigure instances. However, we can't rename it because
+# existing "configuration.nix" files on EC2 instances refer to it.)
+
 { config, lib, pkgs, ... }:
 
 with lib;
-let
-  cfg = config.ec2;
-in
+
+let cfg = config.ec2; in
+
 {
-  imports = [ ../profiles/headless.nix ./ec2-data.nix ];
+  imports = [ ../profiles/headless.nix ./ec2-data.nix ./amazon-grow-partition.nix ];
 
   config = {
-    system.build.amazonImage =
-      pkgs.vmTools.runInLinuxVM (
-        pkgs.runCommand "amazon-image"
-          { preVM =
-              ''
-                mkdir $out
-                diskImage=$out/nixos.img
-                ${pkgs.vmTools.qemu}/bin/qemu-img create -f raw $diskImage "8G"
-                mv closure xchg/
-              '';
-            buildInputs = [ pkgs.utillinux pkgs.perl ];
-            exportReferencesGraph =
-              [ "closure" config.system.build.toplevel ];
-          }
-          ''
-            ${if cfg.hvm then ''
-              # Create a single / partition.
-              ${pkgs.parted}/sbin/parted /dev/vda mklabel msdos
-              ${pkgs.parted}/sbin/parted /dev/vda -- mkpart primary ext2 1M -1s
-              . /sys/class/block/vda1/uevent
-              mknod /dev/vda1 b $MAJOR $MINOR
-
-              # Create an empty filesystem and mount it.
-              ${pkgs.e2fsprogs}/sbin/mkfs.ext4 -L nixos /dev/vda1
-              ${pkgs.e2fsprogs}/sbin/tune2fs -c 0 -i 0 /dev/vda1
-              mkdir /mnt
-              mount /dev/vda1 /mnt
-            '' else ''
-              # Create an empty filesystem and mount it.
-              ${pkgs.e2fsprogs}/sbin/mkfs.ext4 -L nixos /dev/vda
-              ${pkgs.e2fsprogs}/sbin/tune2fs -c 0 -i 0 /dev/vda
-              mkdir /mnt
-              mount /dev/vda /mnt
-            ''}
-
-            # The initrd expects these directories to exist.
-            mkdir /mnt/dev /mnt/proc /mnt/sys
-
-            mount -o bind /proc /mnt/proc
-            mount -o bind /dev /mnt/dev
-            mount -o bind /sys /mnt/sys
-
-            # Copy all paths in the closure to the filesystem.
-            storePaths=$(perl ${pkgs.pathsFromGraph} /tmp/xchg/closure)
-
-            mkdir -p /mnt/nix/store
-            echo "copying everything (will take a while)..."
-            cp -prd $storePaths /mnt/nix/store/
-
-            # Register the paths in the Nix database.
-            printRegistration=1 perl ${pkgs.pathsFromGraph} /tmp/xchg/closure | \
-                chroot /mnt ${config.nix.package}/bin/nix-store --load-db --option build-users-group ""
-
-            # Create the system profile to allow nixos-rebuild to work.
-            chroot /mnt ${config.nix.package}/bin/nix-env --option build-users-group "" \
-                -p /nix/var/nix/profiles/system --set ${config.system.build.toplevel}
-
-            # `nixos-rebuild' requires an /etc/NIXOS.
-            mkdir -p /mnt/etc
-            touch /mnt/etc/NIXOS
-
-            # `switch-to-configuration' requires a /bin/sh
-            mkdir -p /mnt/bin
-            ln -s ${config.system.build.binsh}/bin/sh /mnt/bin/sh
-
-            # Install a configuration.nix.
-            mkdir -p /mnt/etc/nixos
-            cp ${./amazon-config.nix} /mnt/etc/nixos/configuration.nix
-
-            # Generate the GRUB menu.
-            ln -s vda /dev/xvda
-            chroot /mnt ${config.system.build.toplevel}/bin/switch-to-configuration boot
-
-            umount /mnt/proc /mnt/dev /mnt/sys
-            umount /mnt
-          ''
-      );
-
-    fileSystems."/".device = "/dev/disk/by-label/nixos";
+
+    fileSystems."/" = {
+      device = "/dev/disk/by-label/nixos";
+      autoResize = true;
+    };
 
     boot.initrd.kernelModules = [ "xen-blkfront" ];
     boot.kernelModules = [ "xen-netfront" ];
+    boot.kernelParams = mkIf cfg.hvm [ "console=ttyS0" ];
 
     # Prevent the nouveau kernel module from being loaded, as it
     # interferes with the nvidia/nvidia-uvm modules needed for CUDA.
diff --git a/nixos/modules/virtualisation/growpart-util-linux-2.26.patch b/nixos/modules/virtualisation/growpart-util-linux-2.26.patch
new file mode 100644
index 00000000000..c782c2d7e4b
--- /dev/null
+++ b/nixos/modules/virtualisation/growpart-util-linux-2.26.patch
@@ -0,0 +1,88 @@
+From 1895d10a7539d055a4e0206af1e7a9e5ea32a4f7 Mon Sep 17 00:00:00 2001
+From: Juerg Haefliger <juerg.haefliger@hp.com>
+Date: Wed, 25 Mar 2015 13:59:20 +0100
+Subject: [PATCH] Support new sfdisk version 2.26
+
+The sfdisk usage with version 2.26 changed. Specifically, the option
+--show-pt-geometry and functionality for CHS have been removed.
+Also, restoring a backup MBR now needs to be done using dd.
+---
+ bin/growpart | 28 ++++++++++------------------
+ 1 file changed, 10 insertions(+), 18 deletions(-)
+
+diff --git a/bin/growpart b/bin/growpart
+index 595c40b..d4c995b 100755
+--- a/bin/growpart
++++ b/bin/growpart
+@@ -28,7 +28,6 @@ PART=""
+ PT_UPDATE=false
+ DRY_RUN=0
+ 
+-MBR_CHS=""
+ MBR_BACKUP=""
+ GPT_BACKUP=""
+ _capture=""
+@@ -133,7 +132,8 @@ bad_Usage() {
+ }
+ 
+ mbr_restore() {
+-	sfdisk --no-reread "${DISK}" ${MBR_CHS} -I "${MBR_BACKUP}"
++	dd if="${MBR_BACKUP}-${DISK#/dev/}-0x00000000.bak" of="${DISK}" bs=1 \
++		conv=notrunc
+ }
+ 
+ sfdisk_worked_but_blkrrpart_failed() {
+@@ -148,34 +148,26 @@ sfdisk_worked_but_blkrrpart_failed() {
+ 
+ mbr_resize() {
+ 	RESTORE_HUMAN="${TEMP_D}/recovery"
+-	MBR_BACKUP="${TEMP_D}/orig.save"
++	MBR_BACKUP="${TEMP_D}/backup"
+ 
+ 	local change_out=${TEMP_D}/change.out
+ 	local dump_out=${TEMP_D}/dump.out
+ 	local new_out=${TEMP_D}/new.out
+ 	local dump_mod=${TEMP_D}/dump.mod
+-	local tmp="${TEMP_D}/tmp.out"
+-	local err="${TEMP_D}/err.out"
+ 
+-	local _devc cyl _w1 heads _w2 sectors _w3 tot dpart
++	local tot dpart
+ 	local pt_start pt_size pt_end max_end new_size change_info
+ 
+-	# --show-pt-geometry outputs something like
+-	#     /dev/sda: 164352 cylinders, 4 heads, 32 sectors/track
+-	rqe sfd_geom sfdisk "${DISK}" --show-pt-geometry >"${tmp}" &&
+-		read _devc cyl _w1 heads _w2 sectors _w3 <"${tmp}" &&
+-		MBR_CHS="-C ${cyl} -H ${heads} -S ${sectors}" ||
+-		fail "failed to get CHS from ${DISK}"
++	tot=$(sfdisk --list "${DISK}" | awk '{ print $(NF-1) ; exit }') ||
++		fail "failed to get total number of sectors from ${DISK}"
+ 
+-	tot=$((${cyl}*${heads}*${sectors}))
++	debug 1 "total number of sectors of ${DISK} is ${tot}"
+ 
+-	debug 1 "geometry is ${MBR_CHS}. total size=${tot}"
+-	rqe sfd_dump sfdisk ${MBR_CHS} --unit=S --dump "${DISK}" \
++	rqe sfd_dump sfdisk --dump "${DISK}" \
+ 		>"${dump_out}" ||
+ 		fail "failed to dump sfdisk info for ${DISK}"
+-
+ 	{
+-		echo "## sfdisk ${MBR_CHS} --unit=S --dump ${DISK}"
++		echo "## sfdisk --dump ${DISK}"
+ 		cat "${dump_out}"
+ 	}  >"${RESTORE_HUMAN}"
+ 	[ $? -eq 0 ] || fail "failed to save sfdisk -d output"
+@@ -237,7 +229,7 @@ mbr_resize() {
+ 		exit 0
+ 	fi
+ 
+-	LANG=C sfdisk --no-reread "${DISK}" ${MBR_CHS} --force \
++	LANG=C sfdisk --no-reread "${DISK}" --force \
+ 		-O "${MBR_BACKUP}" <"${new_out}" >"${change_out}" 2>&1
+ 	ret=$?
+ 	[ $ret -eq 0 ] || RESTORE_FUNC="mbr_restore"
+-- 
+2.1.4
+