kernel v4.13 introduced the index=on feature for not breaking hardlinks on copy-up. With the index feature enabled a regression was introduced - lower files that are hardlined while overlay is offline can result in lookup error after overlay in mounted. The regression was fixed by upstream commit 6eaf011144af ovl: fix EIO from lookup of non-indexed upper that was merged to v4.14-rc7. This test verifies that behavior is sane after creating lower hardlinks for copied up files while overlayfs is offline. Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- Eryu, This is a regression test for a fix that was just merged to v4.14-rc7. The test requires and enables index=on, so it would fail on kernels prior to v4.14-rc7 regardless if they are complied with CONFIG_OVERLAY_FS_INDEX=y or not. Amir. tests/overlay/042 | 137 ++++++++++++++++++++++++++++++++++++++++++++++++++ tests/overlay/042.out | 2 + tests/overlay/group | 1 + 3 files changed, 140 insertions(+) create mode 100755 tests/overlay/042 create mode 100644 tests/overlay/042.out diff --git a/tests/overlay/042 b/tests/overlay/042 new file mode 100755 index 0000000..29858d6 --- /dev/null +++ b/tests/overlay/042 @@ -0,0 +1,137 @@ +#! /bin/bash +# FS QA Test 042 +# +# Test creating lower hardlinks for copied up files. +# +# kernel v4.13 introduced the index=on feature for not breaking +# hardlinks on copy-up. With the index feature enabled a regression was +# introduced - lower files that are hardlined while overlay is offline +# can result in lookup error after overlay in mounted. +# The regression was fixed by upstream commit +# 6eaf011144af ovl: fix EIO from lookup of non-indexed upper +# that was merged to v4.14-rc7. +# +# This test verifies that behavior is sane after creating lower hardlinks +# for copied up files while overlayfs is offline. +# +#----------------------------------------------------------------------- +# Copyright (C) 2017 CTERA Networks. All Rights Reserved. +# Author: Amir Goldstein <amir73il@xxxxxxxxx> +# +# 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. +# +# 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 +#----------------------------------------------------------------------- +# + +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +tmp=/tmp/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +_cleanup() +{ + cd / + rm -f $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# remove previous $seqres.full before test +rm -f $seqres.full + +# real QA test starts here +_supported_fs overlay +_supported_os Linux +_require_scratch +# Without overlay index feature hardlinks are broken on copy up +_require_scratch_feature index + +# Remove all files from previous tests +_scratch_mkfs + +# Create lower file +lowerdir=$OVL_BASE_SCRATCH_MNT/$OVL_LOWER +mkdir -p $lowerdir +touch $lowerdir/0 + +# Disable overlay index feature to copy up with no index +_scratch_mount -o index=off + +# Copy up lower and create upper hardlink with no index +ln $SCRATCH_MNT/0 $SCRATCH_MNT/1 + +$UMOUNT_PROG $SCRATCH_MNT + +# Add lower hardlinks while overlay is offline +ln $lowerdir/0 $lowerdir/2 +ln $lowerdir/0 $lowerdir/3 + +# Enable overlay index feature to lookup copied up upper aliases +_scratch_mount -o index=on + +# Stat upper hardlink that were created with no index and whose copy up +# origin is now an hardlink - expect same st_ino +ino0=$(stat -c '%i' $SCRATCH_MNT/0) +ino1=$(stat -c '%i' $SCRATCH_MNT/1) +[[ $ino0 == $ino1 ]] || \ + echo "Mismatch inode number for non-indexed upper hardlinks" + +# Copy up lower and create new upper hardlink with index, because +# lower is a hardlink and index is enabled. The new hardlinks are not +# associated with the hardlinks that were created when lower was not +# a hardlink. +ln $SCRATCH_MNT/2 $SCRATCH_MNT/4 + +# Mount cycle to reset inode/dentry cache +_scratch_cycle_mount index=on + +# Stat files that were copied up with index and whose copy up origin +# is now an hardlink - expect same st_ino as lower aliases and different +# st_ino from non-indexed upper aliases. +ino0=$(stat -c '%i' $SCRATCH_MNT/0) +ino1=$(stat -c '%i' $SCRATCH_MNT/1) +ino2=$(stat -c '%i' $SCRATCH_MNT/2) +ino3=$(stat -c '%i' $SCRATCH_MNT/3) +ino4=$(stat -c '%i' $SCRATCH_MNT/4) +[[ $ino0 == $ino1 ]] || \ + echo "Mismatch inode number for non-indexed upper hardlinks" +[[ $ino2 == $ino4 ]] || \ + echo "Mismatch inode number for indexed upper hardlinks" +[[ $ino2 == $ino3 ]] || \ + echo "Mismatch inode number for indexed upper and lower hardlinks" +[[ $ino2 != $ino0 ]] || \ + echo "Unexpected matching inode number for indexed and non-indexed upper hardlinks" + +# Mount cycle to reset inode/dentry cache +_scratch_cycle_mount index=on + +# Unlink all hardlinks - if overlay inode nlink is 0, this will trigger +# WARN_ON() in drop_nlink() +rm $SCRATCH_MNT/0 +rm $SCRATCH_MNT/1 +rm $SCRATCH_MNT/2 +rm $SCRATCH_MNT/3 +rm $SCRATCH_MNT/4 + +# Verify that orphan index is cleaned on mount +_scratch_cycle_mount index=on +ls $OVL_BASE_SCRATCH_MNT/$OVL_WORK/index + +echo "Silence is golden" +status=0 +exit diff --git a/tests/overlay/042.out b/tests/overlay/042.out new file mode 100644 index 0000000..85eac7a --- /dev/null +++ b/tests/overlay/042.out @@ -0,0 +1,2 @@ +QA output created by 042 +Silence is golden diff --git a/tests/overlay/group b/tests/overlay/group index 8629325..782c39f 100644 --- a/tests/overlay/group +++ b/tests/overlay/group @@ -44,3 +44,4 @@ 039 auto quick atime 040 auto quick 041 auto quick copyup nonsamefs +042 auto quick copyup hardlink -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html