#!/bin/bash
# Copyright (C) 2018 Oracle. All Rights Reserved.
#
# Author: Darrick J. Wong <darrick.wong@oracle.com>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it would be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
# Automatically check an LVM-managed filesystem online.
# We use lvm snapshots to do this, which means that we can only
# check filesystems in VGs that have at least 256MB (or so) of
# free space.
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
if (( $EUID != 0 )); then
echo "e2scrub must be run as root"
exit 1
fi
snap_size_mb=256
fstrim=0
reap=0
e2fsck_opts=""
conffile="/etc/e2scrub.conf"
test -f "${conffile}" && . "${conffile}"
print_help() {
echo "Usage: $0 [OPTIONS] mountpoint | device"
echo
echo "mountpoint must be on an LVM-managed block device"
echo "-n: Show what commands e2scrub would execute."
echo "-r: Remove e2scrub snapshot and exit, do not check anything."
echo "-t: Run fstrim if successful."
echo "-V: Print version information and exit."
}
print_version() {
echo "e2scrub 1.46.5 (30-Dec-2021)"
}
exitcode() {
ret="$1"
# If we're being run as a service, the return code must fit the LSB
# init script action error guidelines, which is to say that we
# compress all errors to 1 ("generic or unspecified error", LSB 5.0
# section 22.2) and hope the admin will scan the log for what
# actually happened.
# We have to sleep 2 seconds here because journald uses the pid to
# connect our log messages to the systemd service. This is critical
# for capturing all the log messages if the scrub fails, because the
# fail service uses the service name to gather log messages for the
# error report.
if [ -n "${SERVICE_MODE}" -a "${ret}" -ne 0 ]; then
test "${ret}" -ne 0 && ret=1
sleep 2
fi
exit "${ret}"
}
while getopts "nrtV" opt; do
case "${opt}" in
"n") DBG="echo Would execute: " ;;
"r") reap=1;;
"t") fstrim=1;;
"V") print_version; exitcode 0;;
*) print_help; exitcode 2;;
esac
done
shift "$((OPTIND - 1))"
arg="$1"
if [ -z "${arg}" ]; then
print_help
exitcode 1
fi
if ! type lsblk >& /dev/null ; then
echo "e2scrub: can't find lsblk --- is util-linux installed?"
exitcode 1
fi
if ! type lvcreate >& /dev/null ; then
echo "e2scrub: can't find lvcreate --- is lvm2 installed?"
exitcode 1
fi
# close file descriptor 3 (from cron) since it causes lvm to kvetch
exec 3<&-
# Find the device for a given mountpoint
dev_from_mount() {
local mountpt="$(realpath "$1")"
lsblk -o NAME,FSTYPE,MOUNTPOINT -p -P -n 2> /dev/null | while read vars; do
eval "${vars}"
if [ "${mountpt}" != "${MOUNTPOINT}" ]; then
continue
fi
case "${FSTYPE}" in
ext[234])
echo "${NAME}"
return 0
;;
esac
done
return 1
}
# Check a device argument
dev_from_arg() {
local dev="$1"
local fstype="$(lsblk -o FSTYPE -n "${dev}" 2> /dev/null)"
case "${fstype}" in
ext[234])
echo "${dev}"
return 0
;;
esac
return 1
}
mnt_from_dev() {
local dev="$1"
if [ -n "${dev}" ]; then
lsblk -o MOUNTPOINT -n "${dev}"
fi
}
# Construct block device path and mountpoint from argument
if [ -b "${arg}" ]; then
dev="$(dev_from_arg "${arg}")"
mnt="$(mnt_from_dev "${dev}")"
else
dev="$(dev_from_mount "${arg}")"
mnt="${arg}"
fi
if [ ! -e "${dev}" ]; then
echo "${arg}: Not an ext[234] filesystem."
print_help
exitcode 16
fi
# Make sure this is an LVM device we can snapshot
lvm_vars="$(lvs --nameprefixes -o name,vgname,lv_role --noheadings "${dev}" 2> /dev/null)"
eval "${lvm_vars}"
if [ -z "${LVM2_VG_NAME}" ] || [ -z "${LVM2_LV_NAME}" ] ||
echo "${LVM2_LV_ROLE}" | grep -q "snapshot"; then
echo "${arg}: Not connnected to an LVM logical volume."
print_help
exitcode 16
fi
start_time="$(date +'%Y%m%d%H%M%S')"
snap="${LVM2_LV_NAME}.e2scrub"
snap_dev="/dev/${LVM2_VG_NAME}/${snap}"
teardown() {
# Remove and wait for removal to succeed.
${DBG} lvremove -f "${LVM2_VG_NAME}/${snap}"
while [ -e "${snap_dev}" ] && [ "$?" -eq "5" ]; do
sleep 0.5
${DBG} lvremove -f "${LVM2_VG_NAME}/${snap}"
done
}
check() {
# First we recover the journal, then we see if e2fsck tries any
# non-optimization repairs. If either of these two returns a
# non-zero status (errors fixed or remaining) then this fs is bad.
E2FSCK_FIXES_ONLY=1
export E2FSCK_FIXES_ONLY
${DBG} "/sbin/e2fsck" -E journal_only -p ${e2fsck_opts} "${snap_dev}" || return $?
${DBG} "/sbin/e2fsck" -f -y ${e2fsck_opts} "${snap_dev}"
}
mark_clean() {
${DBG} "/sbin/tune2fs" -C 0 -T "${start_time}" "${dev}"
}
mark_corrupt() {
${DBG} "/sbin/tune2fs" -E force_fsck "${dev}"
}
setup() {
# Try to remove snapshot for 30s, bail out if we can't remove it.
lvremove_deadline="$(( $(date "+%s") + 30))"
${DBG} lvremove -f "${LVM2_VG_NAME}/${snap}" 2>/dev/null
while [ -e "${snap_dev}" ] && [ "$?" -eq "5" ] &&
[ "$(date "+%s")" -lt "${lvremove_deadline}" ]; do
sleep 0.5
${DBG} lvremove -f "${LVM2_VG_NAME}/${snap}"
done
if [ -e "${snap_dev}" ]; then
echo "${arg}: e2scrub snapshot is in use, cannot check!"
return 1
fi
# Create the snapshot, wait for device to appear.
${DBG} lvcreate -s -L "${snap_size_mb}m" -n "${snap}" "${LVM2_VG_NAME}/${LVM2_LV_NAME}"
if [ $? -ne 0 ]; then
echo "${arg}: e2scrub snapshot FAILED, will not check!"
return 1
fi
${DBG} udevadm settle 2> /dev/null
return 0
}
if [ "${reap}" -gt 0 ]; then
if [ -e "${snap_dev}" ]; then
teardown 2> /dev/null
fi
exit 0
fi
if ! setup; then
exitcode 8
fi
trap "teardown; exit 1" EXIT INT QUIT TERM
# Check and react
check
case "$?" in
"0")
# Clean check!
echo "${arg}: Scrub succeeded."
mark_clean
teardown
trap '' EXIT
# Trim the free space, which requires the snapshot be deleted.
if [ "${fstrim}" -eq 1 ] && [ -d "${mnt}" ] && type fstrim > /dev/null 2>&1; then
echo "${arg}: Trimming free space."
fstrim -v "${mnt}"
fi
ret=0
;;
"8")
# Operational error, what now?
echo "${arg}: e2fsck operational error."
teardown
trap '' EXIT
ret=8
;;
*)
# fsck failed. Check if the snapshot is invalid; if so, make a
# note of that at the end of the log. This isn't necessarily a
# failure because the mounted fs could have overflowed the
# snapshot with regular disk writes /or/ our repair process
# could have done it by repairing too much.
#
# If it's really corrupt we ought to fsck at next boot.
is_invalid="$(lvs -o lv_snapshot_invalid --noheadings "${snap_dev}" | awk '{print $1}')"
if [ -n "${is_invalid}" ]; then
echo "${arg}: Scrub FAILED due to invalid snapshot."
ret=8
else
echo "${arg}: Scrub FAILED due to corruption! Unmount and run e2fsck -y."
mark_corrupt
ret=6
fi
teardown
trap '' EXIT
;;
esac
exitcode "${ret}"
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