overlay: regression test for hardlink breakage after unlink and mount cycle

- file A and B are hardlinked in lower
- modify A to trigger copy up and index lower
- unlink A and mount cycle
- check that B still contains the modified data

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>

diff --git a/tests/overlay/047 b/tests/overlay/047
new file mode 100755 (executable)
index 0000000..ad1aabe
--- /dev/null
+++ b/tests/overlay/047
@@ -0,0 +1,107 @@
+#! /bin/bash
+# FSQA Test No. 047
+#
+# Test hardlink breakage after unlink and mount cycle
+#
+# - file A and B are hardlinked in lower
+# - modify A to trigger copy up and index lower
+# - unlink A and mount cycle
+# - check that B still contains the modified data
+#
+#-----------------------------------------------------------------------
+#
+# Copyright (C) 2016-2017 CTERA Networks. All Rights Reserved.
+# Author: Amir Goldstein <amir73il@gmail.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.
+#
+# 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()
+{
+       rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# real QA test starts here
+_supported_fs overlay
+_supported_os Linux
+_require_scratch
+_require_scratch_feature index
+
+rm -f $seqres.full
+
+_scratch_mkfs >>$seqres.full 2>&1
+
+# Create 2 hardlinked files in lower
+lowerdir=$OVL_BASE_SCRATCH_MNT/$OVL_LOWER
+mkdir -p $lowerdir
+echo "zero" >> $lowerdir/foo
+ln $lowerdir/foo $lowerdir/bar
+
+
+# Enable overlay index feature to prevent breaking hardlinks on copy up
+_scratch_mount -o index=on
+
+
+rm -f $tmp.*
+
+foo=$SCRATCH_MNT/foo
+bar=$SCRATCH_MNT/bar
+
+FILES="$foo $bar"
+
+echo "== Before copy up =="
+cat $foo
+
+# Modify content of one of the hardlinks
+echo "one" >> $bar
+
+echo "== After write one =="
+cat $foo
+
+# Unlink the copied up hardlink
+rm $bar
+
+echo "== After unlink one =="
+cat $foo
+
+# Verify that the hardlinks survive a mount cycle
+_scratch_cycle_mount index=on
+
+echo "== After mount cycle =="
+cat $foo
+
+# Drop caches to get the copied up hardlink out of cache
+echo 3 > /proc/sys/vm/drop_caches
+
+# Modify content of the other hardlink
+echo "two" >> $foo
+
+echo "== After write two =="
+cat $foo
+
+status=0
+exit

diff --git a/tests/overlay/047.out b/tests/overlay/047.out
new file mode 100644 (file)
index 0000000..298e116
--- /dev/null
+++ b/tests/overlay/047.out
@@ -0,0 +1,16 @@
+QA output created by 047
+== Before copy up ==
+zero
+== After write one ==
+zero
+one
+== After unlink one ==
+zero
+one
+== After mount cycle ==
+zero
+one
+== After write two ==
+zero
+one
+two

diff --git a/tests/overlay/group b/tests/overlay/group
index b32c6cdb16496c80bcafc6dc1383e139c6317597..3e31d2df6521826dd97caf48a8245be62dab2506 100644 (file)
--- a/tests/overlay/group
+++ b/tests/overlay/group
@@ -47,3 +47,4 @@
 042 auto quick copyup hardlink
 043 auto quick copyup nonsamefs
 044 auto quick copyup hardlink nonsamefs
 042 auto quick copyup hardlink
 043 auto quick copyup nonsamefs
 044 auto quick copyup hardlink nonsamefs

+047 auto quick copyup hardlink