| Message ID | 1443643065-16460-2-git-send-email-lebedev.ri@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Sep 30, 2015 at 10:57:45PM +0300, Roman Lebedev wrote: > As per overlayfs documentation, any activity on a merged directory > for a application that is doing such activity should work exactly > as if that would be a normal, non overlayfs-merged directory. > > That is, e.g. simple fopen-fwrite-fsync-fclose sequence should > work just fine. We have plenty of tests that do things like that. > But apparently it does not. Add a simple generic test to check that. > As of right now (linux-4.2.1) this test fails at least on btrfs. > > PS: An alternative (and probably better approach) would be to run > fstests test suite with TEST_DIR set to overlayfs work directory. Much better is to run xfstests directly on overlayfs. THere have been some patches to do that posted in the past, but those patches and discussions kinda ended up going nowhere: http://www.mail-archive.com/fstests@vger.kernel.org/msg00474.html Perhaps you'd like to pick this up, and then overlay will by much easier to test and hence likely not to have bugs like this... Cheers, Dave.
On 9/30/15 4:56 PM, Dave Chinner wrote: > On Wed, Sep 30, 2015 at 10:57:45PM +0300, Roman Lebedev wrote: >> As per overlayfs documentation, any activity on a merged directory >> for a application that is doing such activity should work exactly >> as if that would be a normal, non overlayfs-merged directory. >> >> That is, e.g. simple fopen-fwrite-fsync-fclose sequence should >> work just fine. > > We have plenty of tests that do things like that. > >> But apparently it does not. Add a simple generic test to check that. >> As of right now (linux-4.2.1) this test fails at least on btrfs. >> >> PS: An alternative (and probably better approach) would be to run >> fstests test suite with TEST_DIR set to overlayfs work directory. > > Much better is to run xfstests directly on overlayfs. THere have > been some patches to do that posted in the past, but those patches > and discussions kinda ended up going nowhere: > > http://www.mail-archive.com/fstests@vger.kernel.org/msg00474.html > > Perhaps you'd like to pick this up, and then overlay will by much > easier to test and hence likely not to have bugs like this... Yeah, that could still be used for fun, but Zach's POV was that we should just have a specific overlayfs config (dictating paths to over/under/merge/around/through/whatever directories), a special mount_overlayfs helper, etc, ala NFS & CIFS. It may actually be easier than what I proposed. If you want to take a stab at it I'm happy to help, answer questions, etc - I'm not sure when I'll get back to it... -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/tests/generic/111 b/tests/generic/111 new file mode 100755 index 0000000..3c2599b --- /dev/null +++ b/tests/generic/111 @@ -0,0 +1,80 @@ +#! /bin/bash +# FS QA Test 111 +# +# Test that fsync works on file in overlayfs merged directory +# +#----------------------------------------------------------------------- +# Copyright (c) 2015 Roman Lebedev. 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/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +lower=$TEST_DIR/lower.$$ +upper=$TEST_DIR/upper.$$ +work=$TEST_DIR/work.$$ +merged=$TEST_DIR/merged.$$ + +_cleanup() +{ + cd / + rm -f $tmp.* + umount $merged + rm -rf $merged + rm -rf $work + rm -rf $upper + rm -rf $lower +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# real QA test starts here + +_supported_fs generic +_supported_os IRIX Linux +_require_test + +mkdir $lower + +$XFS_IO_PROG -f -c "pwrite 0 4k" -c "fsync" \ + $lower/file | _filter_xfs_io + +mkdir $upper +mkdir $work +mkdir $merged + +sync + +mount -t overlay overlay -olowerdir=$lower \ + -oupperdir=$upper -oworkdir=$work $merged + +$XFS_IO_PROG -f -c "pwrite 0 4k" -c "fsync" \ + $merged/file | _filter_xfs_io + +# if we are here, then fsync did not crash, so we're good. + +# success, all done +status=0 +exit diff --git a/tests/generic/111.out b/tests/generic/111.out new file mode 100644 index 0000000..36c7fde --- /dev/null +++ b/tests/generic/111.out @@ -0,0 +1,5 @@ +QA output created by 111 +wrote 4096/4096 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 4096/4096 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) diff --git a/tests/generic/group b/tests/generic/group index 4ae256f..d3516f9 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -112,6 +112,7 @@ 107 auto quick metadata 108 auto quick rw 109 auto metadata dir +111 auto quick 112 rw aio auto quick 113 rw aio auto quick 117 attr auto quick
As per overlayfs documentation, any activity on a merged directory for a application that is doing such activity should work exactly as if that would be a normal, non overlayfs-merged directory. That is, e.g. simple fopen-fwrite-fsync-fclose sequence should work just fine. But apparently it does not. Add a simple generic test to check that. As of right now (linux-4.2.1) this test fails at least on btrfs. PS: An alternative (and probably better approach) would be to run fstests test suite with TEST_DIR set to overlayfs work directory. Also, i'm not sure that this test fits here, but it's my best guess. Signed-off-by: Roman Lebedev <lebedev.ri@gmail.com> --- tests/generic/111 | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++ tests/generic/111.out | 5 ++++ tests/generic/group | 1 + 3 files changed, 86 insertions(+) create mode 100755 tests/generic/111 create mode 100644 tests/generic/111.out