Even the fallocate range doesn't cover the last page of a file, btrfs will still re-truncate the last page. Such behavior is completely duplicated and unneeded, and fixed by the following kernel patch: btrfs: Avoid truncate tailing page if fallocate range doesn't exceed inode size Add this test case to check that malfunction. Signed-off-by: Qu Wenruo <quwenruo@xxxxxxxxxxxxxx> --- tests/btrfs/104 | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++ tests/btrfs/104.out | 3 ++ tests/btrfs/group | 1 + 3 files changed, 87 insertions(+) create mode 100755 tests/btrfs/104 create mode 100644 tests/btrfs/104.out diff --git a/tests/btrfs/104 b/tests/btrfs/104 new file mode 100755 index 0000000..f3ddc15 --- /dev/null +++ b/tests/btrfs/104 @@ -0,0 +1,83 @@ +#! /bin/bash +# FS QA Test 104 +# +# Test that calling fallocate against a range which is already +# allocated does not truncate beyond EOF +# +#----------------------------------------------------------------------- +# Copyright (c) 2015 Fujitsu. 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 +. ./common/defrag + +# remove previous $seqres.full before test +rm -f $seqres.full + +# real QA test starts here + +_supported_fs btrfs +_supported_os Linux +_require_scratch +_need_to_be_root + +# Use 64K file size to match any sectorsize +# And with a unaligned tailing range to ensure it will be at least 2 pages +filesize=$(( 64 * 1024 + 1024 )) + +# Fallocate a range that will not cover the tailing page +fallocrange=$(( 64 * 1024 )) + +_scratch_mkfs > /dev/null 2>&1 +_scratch_mount +$XFS_IO_PROG -f -c "pwrite 0 $filesize" $SCRATCH_MNT/foo | _filter_xfs_io +sync +orig_extent_nr=`_extent_count $SCRATCH_MNT/foo` + +# As all space are allocated and even written to disk, this falloc +# should do nothing with extent modification. +$XFS_IO_PROG -f -c "falloc 0 $fallocrange" $SCRATCH_MNT/foo +sync +new_extent_nr=`_extent_count $SCRATCH_MNT/foo` + +echo "orig: $orig_extent_nr, new: $new_extent_nr" >> $seqres.full + +if [ "x$orig_extent_nr" != "x$new_extent_nr" ]; then + echo "Extent beyond EOF is re-truncated" + echo "orig_extent_nr: $orig_extent_nr new_extent_nr: $new_extent_nr" +fi + +# success, all done +status=0 +exit diff --git a/tests/btrfs/104.out b/tests/btrfs/104.out new file mode 100644 index 0000000..4c43e17 --- /dev/null +++ b/tests/btrfs/104.out @@ -0,0 +1,3 @@ +QA output created by 104 +wrote 66560/66560 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) diff --git a/tests/btrfs/group b/tests/btrfs/group index e92a65a..640336b 100644 --- a/tests/btrfs/group +++ b/tests/btrfs/group @@ -106,3 +106,4 @@ 101 auto quick replace 102 auto quick metadata enospc 103 auto quick clone compress +104 auto quick prealloc -- 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