diskimage-builder/lib/common-functions
Markos Chandras a1f57b8cad lib: common-functions: Fix tmpfs umounting
It has been observed that some chroot operations spawn additional
processes which rely on chroot files. More specifically, zypper, uses
gpg-agent to import and validate gpg keys for its repositories. This
gpg-agent process may stay alive for longer which prevents unmounting of
the tmpfs directory since the gpg-agent process still uses libraries etc
which were present in the chroot. We try to solve this by using walking
all the pids in /proc to find out the running processes in the chroot and
kill them gracefully. If that fails for whatever reason, then we simply
keep trying to umount the tmpfs directory before we give up.

The gpg-agent process usually terminates soon after its home directory
disappears but on fast systems we can reach the 'umount tmpfs' point
before gpg-agent terminates by itself. The solution is generic enough so
other 'chroot processes' can also be handled appropriately.

Change-Id: Iccf332678c79266113e76f062884fc5ee79e515d
2016-11-16 15:44:01 +00:00

303 lines
9.4 KiB
Bash

#!/bin/bash
# Copyright 2012 Hewlett-Packard Development Company, L.P.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
function tmpfs_check() {
local echo_message=${1:-1}
[ "$DIB_NO_TMPFS" == "0" ] || return 1
[ -r /proc/meminfo ] || return 1
total_kB=$(awk '/^MemTotal/ { print $2 }' /proc/meminfo)
# tmpfs uses by default 50% of the available RAM, so the RAM should be at least
# the double of the minimum tmpfs size required
RAM_NEEDED=$(($DIB_MIN_TMPFS * 2))
[ $total_kB -lt $(($RAM_NEEDED*1024*1024)) ] || return 0
if [ $echo_message == '1' ]; then
echo "WARNING: Not enough RAM to use tmpfs for build. Using ${TMP_DIR:-/tmp}. ($total_kB < ${RAM_NEEDED}G)"
fi
return 1
}
function mk_build_dir () {
TMP_BUILD_DIR=$(mktemp -t -d --tmpdir=${TMP_DIR:-/tmp} dib_build.XXXXXXXX)
TMP_IMAGE_DIR=$(mktemp -t -d --tmpdir=${TMP_DIR:-/tmp} dib_image.XXXXXXXX)
[ $? -eq 0 ] || die "Failed to create tmp directory"
export TMP_BUILD_DIR
if tmpfs_check ; then
sudo mount -t tmpfs tmpfs $TMP_BUILD_DIR
sudo mount -t tmpfs tmpfs $TMP_IMAGE_DIR
sudo chown $(id -u):$(id -g) $TMP_BUILD_DIR $TMP_IMAGE_DIR
fi
trap trap_cleanup EXIT
echo Building in $TMP_BUILD_DIR
export TMP_IMAGE_PATH=$TMP_IMAGE_DIR/image.raw
export OUT_IMAGE_PATH=$TMP_IMAGE_PATH
export TMP_HOOKS_PATH=$TMP_BUILD_DIR/hooks
}
function finish_image () {
if [ -f $1 -a ${OVERWRITE_OLD_IMAGE:-0} -eq 0 ]; then
old_image="${1%.*}"-$(date +%Y.%m.%d-%H.%M.%S).${1##*.}
echo "Old image found. Renaming it to $old_image"
mv "$1" "$old_image"
if [ -f "$1.md5" ]; then
mv "$1.md5" "$old_image.md5"
fi
if [ -f "$1.sha256" ]; then
mv "$1.sha256" "$old_image.sha256"
fi
fi
mv $OUT_IMAGE_PATH $1
if [ "$DIB_CHECKSUM" == "1" ]; then
md5sum $1 > $1.md5
sha256sum $1 > $1.sha256
fi
echo "Image file $1 created..."
}
function save_image () {
finish_image $1
}
function copy_hooks_not_overwrite () {
_DIR=$(basename $1)
test -d $TMP_HOOKS_PATH/$_DIR || mkdir $TMP_HOOKS_PATH/$_DIR
for _HOOK in $(ls $1); do
if [ ! -f $TMP_HOOKS_PATH/$_DIR/$_HOOK ]; then
cp -t $TMP_HOOKS_PATH/$_DIR -a $1/$_HOOK
else
echo "There is a duplicated hook in your elements: $_ELEMENT/$_DIR/$_HOOK"
exit 1
fi
done
}
function generate_hooks () {
mkdir -p $TMP_HOOKS_PATH
for _ELEMENT in $IMAGE_ELEMENT ; do
for dir in ${ELEMENTS_PATH//:/ } ; do
[ -d $dir/$_ELEMENT ] || continue
for _DIR in $(find $dir/$_ELEMENT -follow -mindepth 1 -maxdepth 1 -type d -not -name tests); do
copy_hooks_not_overwrite $_DIR
done
for _FILE in $(find $dir/$_ELEMENT -follow -maxdepth 1 -type f); do
cp -t $TMP_HOOKS_PATH -a $_FILE
done
break
done
done
}
# Call the supplied break-in routine if the named point is listed in the break
# list.
# $1 the break point.
# $2.. what to call if a break is needed
function check_break () {
if echo "${break:-}" | egrep -e "(,|^)$1(,|$)" -q; then
echo "Starting debug shell. Exit to resume building." >&2
echo At stage $1 >&2
shift
"$@"
echo "Resuming" >&2
fi
}
# Check that a real element has been chosen (prevents foot-guns)
function check_element () {
[ -d $TMP_HOOKS_PATH ] || generate_hooks
}
# Run a hook, looking for a regex in its stdout, and eval the matched lines.
# $1 is the hook to run
# $2 is the regex to look for
function eval_run_d () {
local run_output=$(mktemp)
trap "rm -f $run_output; check_break after-error ${break_cmd:-bash}" ERR
run_d $1 $run_output
if grep -q "$2" $run_output; then
local temp=$(grep "$2" $run_output)
eval "$temp"
fi
rm $run_output
trap - ERR
}
function kill_chroot_processes () {
if [ -z "${1}" ]; then
echo "ERROR: no chroot directory specified"
exit 1
fi
for piddir in /proc/[0-9]*; do
pid=${piddir##/proc/}
pidname=$(cat $piddir/comm 2>/dev/null || echo "unknown")
# If there are open files from the chroot, just kill the process using
# these files.
if sudo readlink -f $piddir/root | grep -q $TMP_BUILD_DIR; then
echo "Killing chroot process: '${pidname}($pid)'"
sudo kill $pid
fi
done
}
function cleanup_build_dir () {
if ! timeout 5 sh -c " while ! sudo rm -rf $TMP_BUILD_DIR/built; do sleep 1; done"; then
echo "ERROR: unable to cleanly remove $TMP_BUILD_DIR/built"
exit 1
fi
sudo rm -rf $TMP_BUILD_DIR/mnt
kill_chroot_processes $TMP_BUILD_DIR
if tmpfs_check 0; then
# If kill_chroot_processes did not succeed then we have to wait for
# init to reap the orphaned chroot processes
if ! timeout 120 sh -c "while ! sudo umount -f $TMP_BUILD_DIR; do sleep 1; done"; then
echo "ERROR: failed to umount the $TMP_BUILD_DIR tmpfs mount point"
exit 1
fi
fi
rm -rf --one-file-system $TMP_BUILD_DIR
}
function cleanup_image_dir () {
kill_chroot_processes $TMP_IMAGE_DIR
if tmpfs_check 0; then
if ! timeout 120 sh -c "while ! sudo umount -f $TMP_IMAGE_DIR; do sleep 1; done"; then
echo "ERROR: failed to umount the $TMP_IMAGE_DIR tmpfs mount point"
exit 1
fi
fi
rm -rf --one-file-system $TMP_IMAGE_DIR
}
# Run a directory of hooks outside the target (that is, no chrooting).
function run_d() {
check_element
check_break before-$1 ${break_cmd:-bash}
if [ -d ${TMP_HOOKS_PATH}/$1.d ] ; then
if [ -n "$2" ]; then
dib-run-parts ${TMP_HOOKS_PATH}/$1.d | tee $2
if [[ ${PIPESTATUS[0]} != 0 ]]; then
return 1
fi
else
dib-run-parts ${TMP_HOOKS_PATH}/$1.d
fi
fi
check_break after-$1 bash
}
function detach_loopback() {
local loopdev=$1
# Remove the map if it exists
# If setup on a rhel or derivative the map was created with kpartx not losetup
# and subsequently needs to be removed.
loopdev_name=$(echo $loopdev | sed 's/\/dev\///g')
if sudo dmsetup ls | grep $loopdev_name; then
mapper_name=$(sudo dmsetup ls | grep $loopdev_name | awk '{ print $1 }')
sudo dmsetup --noudevsync remove $mapper_name
fi
# loopback dev may be tied up a bit by udev events triggered by partition events
for try in $(seq 10 -1 1) ; do
if ! sudo losetup $loopdev || sudo losetup -d $loopdev ; then
return 0
fi
echo $loopdev may be busy, sleeping up to $try more seconds...
sleep 1
done
echo Gave up trying to detach $loopdev
return 1
}
function arg_to_elements() {
for arg do IMAGE_ELEMENT="$IMAGE_ELEMENT $arg" ; done
if [ "$SKIP_BASE" != "1" ]; then
IMAGE_ELEMENT="base $IMAGE_ELEMENT"
fi
if [ "$IS_RAMDISK" == "1" ]; then
IMAGE_ELEMENT="$RAMDISK_ELEMENT $IMAGE_ELEMENT"
fi
echo "Building elements: $IMAGE_ELEMENT"
IMAGE_ELEMENT=$($SCRIPT_HOME/element-info $IMAGE_ELEMENT)
export IMAGE_ELEMENT
echo "Expanded element dependencies to: $IMAGE_ELEMENT"
}
function create_base () {
mkdir $TMP_BUILD_DIR/mnt
export TMP_MOUNT_PATH=$TMP_BUILD_DIR/mnt
# Copy data in to the root.
TARGET_ROOT=$TMP_MOUNT_PATH run_d root
if [ -z "$(ls $TMP_MOUNT_PATH | grep -v '^lost+found\|tmp$')" ] ; then
# No root element copied in. Note the test above allows
# root.d elements to put things in /tmp
echo "Failed to deploy the root element."
exit 1
fi
# Configure Image
# Setup resolv.conf so we can chroot to install some packages
if [ -L $TMP_MOUNT_PATH/etc/resolv.conf ] || [ -f $TMP_MOUNT_PATH/etc/resolv.conf ] ; then
sudo mv $TMP_MOUNT_PATH/etc/resolv.conf $TMP_MOUNT_PATH/etc/resolv.conf.ORIG
fi
# Recreate resolv.conf
sudo touch $TMP_MOUNT_PATH/etc/resolv.conf
sudo chmod 777 $TMP_MOUNT_PATH/etc/resolv.conf
# use system configured resolv.conf if available to support internal proxy resolving
if [ -e /etc/resolv.conf ]; then
cat /etc/resolv.conf > $TMP_MOUNT_PATH/etc/resolv.conf
else
echo nameserver 8.8.8.8 > $TMP_MOUNT_PATH/etc/resolv.conf
fi
mount_proc_dev_sys
}
function mount_proc_dev_sys () {
# supporting kernel file systems
sudo mount -t proc none $TMP_MOUNT_PATH/proc
sudo mount --bind /dev $TMP_MOUNT_PATH/dev
sudo mount --bind /dev/pts $TMP_MOUNT_PATH/dev/pts
sudo mount -t sysfs none $TMP_MOUNT_PATH/sys
}
# Recursively unmount directories under a given directory DIR
# usage:
# unmount_dir DIR
function unmount_dir {
local dir="$1"
local real_dir
local mnts
if [ ! -d $dir ]; then
echo "*** $dir is not a directory"
return 1
fi
# get rid of any symlink elements in the incoming path, because
# /proc/mounts is the real path
real_dir=$(readlink -e $dir)
mnts=$(awk '{print $2}' < /proc/mounts | grep "^$real_dir" | sort -r)
for m in $mnts; do
echo "Unmount $m"
sudo umount -fl $m || true
done
}