--- /dev/null
+#! /bin/bash
+# FS QA Test No. 073
+#
+# Test file A fsync after moving one other unrelated file B between directories
+# and fsyncing B's old parent directory before fsyncing the file A. Check that
+# after a crash all the file A data we fsynced is available.
+#
+# This test is motivated by an issue discovered in btrfs which caused the file
+# data to be lost (despite fsync returning success to user space). That btrfs
+# bug was fixed by the following linux kernel patch:
+#
+# Btrfs: fix data loss in the fast fsync path
+#
+#-----------------------------------------------------------------------
+# Copyright (C) 2015 SUSE Linux Products GmbH. All Rights Reserved.
+# Author: Filipe Manana <fdmanana@suse.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"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1 # failure is the default!
+
+_cleanup()
+{
+ _cleanup_flakey
+ rm -f $tmp.*
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/dmflakey
+
+# real QA test starts here
+_supported_fs generic
+_supported_os Linux
+_need_to_be_root
+_require_scratch
+_require_dm_flakey
+_require_metadata_journaling $SCRATCH_DEV
+
+rm -f $seqres.full
+
+_scratch_mkfs >> $seqres.full 2>&1
+_init_flakey
+_mount_flakey
+
+# Create our main test file 'foo', the one we check for data loss.
+# By doing an fsync against our file, it makes btrfs clear the 'needs_full_sync'
+# bit from its flags (btrfs inode specific flags).
+$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 8K" \
+ -c "fsync" $SCRATCH_MNT/foo | _filter_xfs_io
+
+# Now create one other file and 2 directories. We will move this second file
+# from one directory to the other later because it forces btrfs to commit its
+# currently open transaction if we fsync the old parent directory. This is
+# necessary to trigger the data loss bug that affected btrfs.
+mkdir $SCRATCH_MNT/testdir_1
+touch $SCRATCH_MNT/testdir_1/bar
+mkdir $SCRATCH_MNT/testdir_2
+
+# Make sure everything is durably persisted.
+sync
+
+# Write more 8Kb of data to our file.
+$XFS_IO_PROG -c "pwrite -S 0xbb 8K 8K" $SCRATCH_MNT/foo | _filter_xfs_io
+
+# Move our 'bar' file into a new directory.
+mv $SCRATCH_MNT/testdir_1/bar $SCRATCH_MNT/testdir_2/bar
+
+# Fsync our first directory. Because it had a file moved into some other
+# directory, this made btrfs commit the currently open transaction. This is
+# a condition necessary to trigger the data loss bug.
+$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/testdir_1
+
+# Now fsync our main test file. If the fsync succeeds, we expect the 8Kb of
+# data we wrote previously to be persisted and available if a crash happens.
+# This did not happen with btrfs, because of the transaction commit that
+# happened when we fsynced the parent directory.
+$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
+
+# Simulate a crash/power loss.
+_load_flakey_table $FLAKEY_DROP_WRITES
+_unmount_flakey
+
+_load_flakey_table $FLAKEY_ALLOW_WRITES
+_mount_flakey
+
+# Now check that all data we wrote before are available.
+echo "File content after log replay:"
+od -t x1 $SCRATCH_MNT/foo
+
+status=0
+exit
projects / xfstests-dev.git / commitdiff