nixpkgs/boot/boot-stage-1.nix
Nicolas Pierron 38e8cf175f * Use normal, dynamically linked binaries for e2fsck, lvm etc. in the
initrd instead of a mix of dietlibc, klibc and static-glibc based
  binaries.  This works by copying what we need from Glibc into the
  initrd and using patchelf to set the ELF interpreter and RPATH
  correctly.  The resulting initrd is about 500 KB smaller, but more
  importantly, it's much easier to maintain - all those
  dietlibc/klibc/static-glibc builds frequently cause build problems.

svn path=/nixos/branches/fix-style/; revision=14178
2009-02-22 16:08:13 +00:00

197 lines
6.6 KiB
Nix

# This Nix expression builds the initial ramdisk, which contains an
# init script that performs the first stage of booting the system: it
# loads the modules necessary to mount the root file system, then
# calls the init in the root file system to start the second boot
# stage.
{pkgs, config}:
let
kernelPackages = config.boot.kernelPackages;
modulesTree = config.system.modulesTree;
in
rec {
# Determine the set of modules that we need to mount the root FS.
modulesClosure = pkgs.makeModulesClosure {
rootModules =
config.boot.initrd.extraKernelModules ++
config.boot.initrd.kernelModules;
kernel = modulesTree;
allowMissing = config.boot.initrd.allowMissing;
};
# Some additional utilities needed in stage 1, like mount, lvm, fsck
# etc. We don't want to bring in all of those packages, so we just
# copy what we need. Instead of using statically linked binaries,
# we just copy what we need from Glibc and use patchelf to make it
# work.
extraUtils = pkgs.runCommand "extra-utils"
{ buildInputs = [pkgs.nukeReferences];
devicemapper = if config.boot.initrd.lvm then pkgs.devicemapper else null;
lvm2 = if config.boot.initrd.lvm then pkgs.lvm2 else null;
allowedReferences = ["out"]; # prevent accidents like glibc being included in the initrd
}
''
ensureDir $out/bin
ensureDir $out/lib
# Copy what we need from Glibc.
cp -p ${pkgs.glibc}/lib/ld-linux*.so.2 $out/lib
cp -p ${pkgs.glibc}/lib/libc.so.* $out/lib
cp -p ${pkgs.glibc}/lib/libpthread.so.* $out/lib
cp -p ${pkgs.glibc}/lib/librt.so.* $out/lib
cp -p ${pkgs.glibc}/lib/libdl.so.* $out/lib
# Copy some utillinux stuff.
cp ${pkgs.utillinux}/bin/mount ${pkgs.utillinux}/bin/umount ${pkgs.utillinux}/sbin/pivot_root $out/bin
# Copy e2fsck and friends.
cp ${pkgs.e2fsprogs}/sbin/e2fsck $out/bin
cp ${pkgs.e2fsprogs}/sbin/tune2fs $out/bin
cp ${pkgs.e2fsprogs}/sbin/fsck $out/bin
ln -s e2fsck $out/bin/fsck.ext2
ln -s e2fsck $out/bin/fsck.ext3
ln -s e2fsck $out/bin/fsck.ext4
cp -pd ${pkgs.e2fsprogs}/lib/lib*.so.* $out/lib
# Copy devicemapper and lvm, if we need it.
if test -n "$devicemapper"; then
cp $devicemapper/sbin/dmsetup $out/bin/dmsetup
cp $devicemapper/lib/libdevmapper.so.*.* $out/lib
cp $lvm2/sbin/lvm $out/bin/lvm
fi
# Copy udev.
cp ${pkgs.udev}/sbin/udevd ${pkgs.udev}/sbin/udevadm $out/bin
cp ${pkgs.udev}/lib/udev/*_id $out/bin
cp ${pkgs.udev}/lib/libvolume_id.so.* $out/lib
# Copy bash.
cp ${pkgs.bash}/bin/bash $out/bin
ln -s bash $out/bin/sh
# Run patchelf to make the programs refer to the copied libraries.
for i in $out/bin/* $out/lib/*; do if ! test -L $i; then nuke-refs $i; fi; done
for i in $out/bin/*; do
if ! test -L $i; then
echo "patching $i..."
patchelf --set-interpreter $out/lib/ld-linux*.so.2 --set-rpath $out/lib $i || true
fi
done
# Make sure that the patchelf'ed binaries still work.
echo "testing patched programs..."
$out/bin/bash --version
export LD_LIBRARY_PATH=$out/lib
$out/bin/mount --version
$out/bin/umount --version
$out/bin/e2fsck -V
$out/bin/tune2fs 2> /dev/null | grep "tune2fs "
$out/bin/fsck -N
$out/bin/udevadm --version
$out/bin/vol_id 2>&1 | grep "no device"
if test -n "$devicemapper"; then
$out/bin/dmsetup --version | grep "version:"
LVM_SYSTEM_DIR=$out $out/bin/lvm 2>&1 | grep "LVM"
fi
''; # */
# The initrd only has to mount / or any FS marked as necessary for
# booting (such as the FS containing /nix/store, or an FS needed for
# mounting /, like / on a loopback).
fileSystems = pkgs.lib.filter
(fs: fs.mountPoint == "/" || (fs ? neededForBoot && fs.neededForBoot))
config.fileSystems;
udevRules = pkgs.stdenv.mkDerivation {
name = "udev-rules";
buildCommand = ''
ensureDir $out
cp ${pkgs.udev}/*/udev/rules.d/60-persistent-storage.rules $out/
substituteInPlace $out/60-persistent-storage.rules \
--replace ata_id ${extraUtils}/bin/ata_id \
--replace usb_id ${extraUtils}/bin/usb_id \
--replace scsi_id ${extraUtils}/bin/scsi_id \
--replace path_id ${extraUtils}/bin/path_id \
--replace vol_id ${extraUtils}/bin/vol_id
''; # */
};
# The udev configuration file for in the initrd.
udevConf = pkgs.writeText "udev-initrd.conf" ''
udev_rules="${udevRules}"
#udev_log="debug"
'';
# The init script of boot stage 1 (loading kernel modules for
# mounting the root FS).
bootStage1 = pkgs.substituteAll {
src = ./boot-stage-1-init.sh;
shell = "${extraUtils}/bin/bash";
isExecutable = true;
inherit modulesClosure udevConf extraUtils;
inherit (config.boot) isLiveCD resumeDevice;
# !!! copy&pasted from upstart-jobs/filesystems.nix.
mountPoints =
if fileSystems == []
then abort "You must specify the fileSystems option!"
else map (fs: fs.mountPoint) fileSystems;
devices = map (fs: if fs ? device then fs.device else "/dev/disk/by-label/${fs.label}") fileSystems;
fsTypes = map (fs: if fs ? fsType then fs.fsType else "auto") fileSystems;
optionss = map (fs: if fs ? options then fs.options else "defaults") fileSystems;
path = [
# `extraUtils' comes first because it overrides the `mount'
# command provided by klibc (which isn't capable of
# auto-detecting FS types).
extraUtils
pkgs.klibcShrunk
];
};
# The closure of the init script of boot stage 1 is what we put in
# the initial RAM disk.
initialRamdisk = pkgs.makeInitrd {
contents = [
{ object = bootStage1;
symlink = "/init";
}
] ++
pkgs.lib.optionals
(config.boot.initrd.enableSplashScreen && kernelPackages.splashutils != null)
[
{ object = pkgs.runCommand "splashutils" {allowedReferences = []; buildInputs = [pkgs.nukeReferences];} ''
ensureDir $out/bin
cp ${kernelPackages.splashutils}/${kernelPackages.splashutils.helperName} $out/bin/splash_helper
nuke-refs $out/bin/*
'';
suffix = "/bin/splash_helper";
symlink = "/${kernelPackages.splashutils.helperName}";
} # */
{ object = import ../helpers/unpack-theme.nix {
inherit (pkgs) stdenv;
theme = config.services.ttyBackgrounds.defaultTheme;
};
symlink = "/etc/splash";
}
];
};
}