This test reproduces a race between a direct I/O read and a mapped write to a hole in a file. On xfs filesystem, it will trigger a BUG_ON(), and this XFS bug has been fixed by: 04197b3 ("xfs: don't BUG() on mixed direct and mapped I/O") Signed-off-by: Xiao Yang <yangx.jy@xxxxxxxxxxxxxx> --- tests/generic/445 | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++ tests/generic/445.out | 2 ++ tests/generic/group | 1 + 3 files changed, 92 insertions(+) create mode 100755 tests/generic/445 create mode 100644 tests/generic/445.out diff --git a/tests/generic/445 b/tests/generic/445 new file mode 100755 index 0000000..28dfcbe --- /dev/null +++ b/tests/generic/445 @@ -0,0 +1,89 @@ +#! /bin/bash +# FS QA Test No. 445 +# +# Regression test for commit: +# 04197b3 ("xfs: don't BUG() on mixed direct and mapped I/O") +# +# This case tests a race between a direct I/O read and a +# mapped write to a hole in a file. On xfs filesystem, it +# will trigger a BUG_ON(). +# +#----------------------------------------------------------------------- +# Copyright (c) 2017 Fujitsu. All Rights Reserved. +# Author: Xiao Yang <yangx.jy@xxxxxxxxxxxxxx> +# +# 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() +{ + rm -rf $tmp.* +} + +# get standard environment and checks +. ./common/rc + +# real QA test starts here +_supported_os Linux +_require_scratch +_require_xfs_io_command "truncate" +_require_xfs_io_command "fpunch" + +rm -f $seqres.full + +# format and mount +_scratch_mkfs > $seqres.full 2>&1 +_scratch_mount >> $seqres.full 2>&1 + +filesz=$((65536 * 2)) + +# create a test file with a hole +$XFS_IO_PROG -f -c "truncate $((filesz * 2))" $SCRATCH_MNT/file >> $seqres.full + +# run a background dio read to a hole in a loop +while true; do + $XFS_IO_PROG -d -c "pread 0 $filesz" $SCRATCH_MNT/file > /dev/null 2>&1 +done & + +dread_pid=$! + +# run mapped write to the same hole as dio read +for i in `seq 0 999`; do + $XFS_IO_PROG -c "mmap 0 $filesz" -c "mwrite 0 $filesz" $SCRATCH_MNT/file \ + > /dev/null + $XFS_IO_PROG -c "fpunch 0 $filesz" $SCRATCH_MNT/file > /dev/null +done + +kill -9 $dread_pid > /dev/null 2>&1 +wait $dread_pid > /dev/null 2>&1 + +echo "Silence is golden" + +# check dmesg, filtering out expected XFS warnings about mixed mmap/dio +if [ "$FSTYP" == "xfs" ]; then + _check_dmesg _filter_xfs_dmesg +else + _check_dmesg +fi +status=$? +exit diff --git a/tests/generic/445.out b/tests/generic/445.out new file mode 100644 index 0000000..44e55d2 --- /dev/null +++ b/tests/generic/445.out @@ -0,0 +1,2 @@ +QA output created by 445 +Silence is golden diff --git a/tests/generic/group b/tests/generic/group index ced111c..39991b1 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -447,3 +447,4 @@ 442 blockdev 443 auto quick rw 444 auto quick acl +445 auto quick dangerous -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe fstests" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html