--- /dev/null
+#! /bin/bash
+# FS QA Test 464
+#
+# Run delalloc writes & append writes & non-data-integrity syncs concurrently
+# to test the race between block map change vs writeback.
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2017 Red Hat Inc. All Rights Reserved.
+#
+# 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!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+ cd /
+ rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+MAXFILES=200
+BLOCK_SZ=65536
+
+LOOP_CNT=10
+LOOP_TIME=5
+PROC_CNT=16
+
+stop=$tmp.stop
+
+# get a random file to work on
+getfile()
+{
+ echo $SCRATCH_MNT/$((RANDOM % MAXFILES))
+}
+
+# delalloc write a relative big file to get enough dirty pages to be written
+# back, and XFS needs big enough file to trigger speculative preallocations, so
+# freeing these eofblocks could change the extent record
+do_write()
+{
+ local blockcount=$((RANDOM % 100))
+ local filesize=$((blockcount * BLOCK_SZ))
+ $XFS_IO_PROG -ftc "pwrite -b $BLOCK_SZ 0 $filesize" `getfile` \
+ >/dev/null 2>&1
+}
+
+# append another dirty page to the file, the writeback might pick it up too if
+# the file is already under writeback
+do_append()
+{
+ echo "test string" >> `getfile`
+}
+
+# issue WB_SYNC_NONE writeback with the '-w' option of sync_range xfs_io
+# command, so that the last dirty page from append write can be picked up in
+# this writeback cycle. This is not mandatory but could help reproduce XFS
+# corruption more easily.
+do_writeback()
+{
+ $XFS_IO_PROG -c "sync_range -w 0 0" `getfile` >/dev/null 2>&1
+}
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# real QA test starts here
+_supported_fs generic
+_supported_os Linux
+# do fsck after each iteration in test
+_require_scratch_nocheck
+_require_xfs_io_command "sync_range"
+
+_scratch_mkfs >>$seqres.full 2>&1
+_scratch_mount
+
+# loop for $LOOP_CNT iterations, and each iteration starts $PROC_CNT processes
+# for each operation and runs for $LOOP_TIME seconds, and check filesystem
+# consistency after each iteration
+for i in `seq 1 $LOOP_CNT`; do
+ rm -f $stop
+ for j in `seq 1 $PROC_CNT`; do
+ while [ ! -e $stop ]; do
+ do_write
+ done &
+
+ while [ ! -e $stop ]; do
+ do_append
+ done &
+
+ while [ ! -e $stop ]; do
+ do_writeback
+ done &
+ done
+ sleep $LOOP_TIME
+ touch $stop
+ wait
+
+ _scratch_unmount
+ # test exits here if fs is inconsistent
+ _check_scratch_fs
+ _scratch_mount
+done
+
+echo "Silence is golden"
+
+# success, all done
+status=0
+exit