From: Filipe Manana Date: Wed, 1 Apr 2015 00:39:24 +0000 (+1100) Subject: btrfs: test cloning of zero length ranges X-Git-Tag: v2022.05.01~2908 X-Git-Url: http://git.apps.os.sepia.ceph.com/?p=xfstests-dev.git;a=commitdiff_plain;h=9edaf22811c2cee3ebeb87cfc1bc28018c7f067b btrfs: test cloning of zero length ranges Test cloning a file range with a length of zero into a destination offset greater than zero. This made btrfs create an extent state record with a start offset greater than the end offset, resulting in chaos such as an infinite loop when evicting an inode. This issue was fixed by the following linux kernel patch: Btrfs: fix inode eviction infinite loop after cloning into it Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: Dave Chinner --- diff --git a/tests/btrfs/086 b/tests/btrfs/086 new file mode 100755 index 00000000..77c8da68 --- /dev/null +++ b/tests/btrfs/086 @@ -0,0 +1,77 @@ +#! /bin/bash +# FS QA Test No. btrfs/086 +# +# Test cloning a file range with a length of zero into a destination offset +# greater than zero. +# +# This made btrfs create an extent state record with a start offset greater than +# the end offset, resulting in chaos such as an infinite loop when evicting an +# inode. +# +# This issue was fixed by the following linux kernel patch: +# +# Btrfs: fix inode eviction infinite loop after cloning into it +# +#----------------------------------------------------------------------- +# Copyright (C) 2015 SUSE Linux Products GmbH. All Rights Reserved. +# Author: Filipe Manana +# +# 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 btrfs +_supported_os Linux +_require_scratch +_require_cloner +_need_to_be_root + +rm -f $seqres.full + +_scratch_mkfs >>$seqres.full 2>&1 +_scratch_mount + +touch $SCRATCH_MNT/foo +touch $SCRATCH_MNT/bar + +# Now attempt to clone foo into bar. Because we pass a length of zero, the +# clone ioctl will adjust the length to match the size of the file foo (minus +# the source offset which is zero) - because the adjusted length value is +# zero, it made btrfs create an extent state record for file bar with a start +# offset (64k) greater then its end offset (64k - 1), which is something never +# supposed to happen and for example it made inode eviction enter an infinite +# loop that dumped a warning trace on each iteration. +$CLONER_PROG -s 0 -d 65536 -l 0 $SCRATCH_MNT/foo $SCRATCH_MNT/bar +echo "bar file size after clone operation: $(stat -c %s $SCRATCH_MNT/bar)" + +status=0 +exit diff --git a/tests/btrfs/086.out b/tests/btrfs/086.out new file mode 100644 index 00000000..1ae87baa --- /dev/null +++ b/tests/btrfs/086.out @@ -0,0 +1,2 @@ +QA output created by 086 +bar file size after clone operation: 0 diff --git a/tests/btrfs/group b/tests/btrfs/group index 1419a2b3..e9c15aff 100644 --- a/tests/btrfs/group +++ b/tests/btrfs/group @@ -88,3 +88,4 @@ 083 auto quick send 084 auto quick send 085 auto quick metadata subvol +086 auto quick clone