On Sun, Mar 7, 2021 at 2:41 PM Eryu Guan <g...@eryu.me> wrote:
>
> On Thu, Feb 11, 2021 at 05:01:18PM +0000, fdman...@kernel.org wrote:
> > From: Filipe Manana <fdman...@suse.com>
> >
> > Test cases where a direct IO write, with O_DSYNC, can not be done and has
> > to fallback to a buffered write.
> >
> > This is motivated by a regression that was introduced in kernel 5.10 by
> > commit 0eb79294dbe328 ("btrfs: dio iomap DSYNC workaround")) and was
> > fixed in kernel 5.11 by commit ecfdc08b8cc65d ("btrfs: remove dio iomap
> > DSYNC workaround").
> >
> > Signed-off-by: Filipe Manana <fdman...@suse.com>
>
> Sorry for the late review..
>
> So this is supposed to fail with v5.10 kernel, right? But I got it
> passedBecause either you are testing with a patched 5.10.x kernel, or you don't have CONFIG_BTRFS_ASSERT=y in your config. The fix landed in 5.10.18: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v5.10.18&id=a6703c71153438d3ebdf58a75d53dd5e57b33095 > > [root@fedoravm xfstests]# ./check -s btrfs btrfs/231 > SECTION -- btrfs > RECREATING -- btrfs on /dev/mapper/testvg-lv1 > FSTYP -- btrfs > PLATFORM -- Linux/x86_64 fedoravm 5.10.0 #6 SMP Sun Mar 7 22:25:35 CST > 2021 > MKFS_OPTIONS -- /dev/mapper/testvg-lv2 > MOUNT_OPTIONS -- /dev/mapper/testvg-lv2 /mnt/scratch > > btrfs/231 13s ... 8s > Ran: btrfs/231 > Passed all 1 tests > > SECTION -- btrfs > ========================= > Ran: btrfs/231 > Passed all 1 tests > > > --- > > tests/btrfs/231 | 61 +++++++++++++++++++++++++++++++++++++++++++++ > > tests/btrfs/231.out | 21 ++++++++++++++++ > > tests/btrfs/group | 1 + > > 3 files changed, 83 insertions(+) > > create mode 100755 tests/btrfs/231 > > create mode 100644 tests/btrfs/231.out > > > > diff --git a/tests/btrfs/231 b/tests/btrfs/231 > > new file mode 100755 > > index 00000000..9a404f57 > > --- /dev/null > > +++ b/tests/btrfs/231 > > @@ -0,0 +1,61 @@ > > +#! /bin/bash > > +# SPDX-License-Identifier: GPL-2.0 > > +# Copyright (C) 2021 SUSE Linux Products GmbH. All Rights Reserved. > > +# > > +# FS QA Test No. btrfs/231 > > +# > > +# Test cases where a direct IO write, with O_DSYNC, can not be done and > > has to > > +# fallback to a buffered write. > > +# > > +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() > > +{ > > + cd / > > + rm -f $tmp.* > > +} > > + > > +# get standard environment, filters and checks > > +. ./common/rc > > +. ./common/filter > > +. ./common/attr > > + > > +# real QA test starts here > > +_supported_fs btrfs > > +_require_scratch > > +_require_odirect > > +_require_chattr c > > + > > +rm -f $seqres.full > > + > > +_scratch_mkfs >>$seqres.full 2>&1 > > +_scratch_mount > > + > > +# First lets test with an attempt to write into a file range with > > compressed > > +# extents. > > +touch $SCRATCH_MNT/foo > > +$CHATTR_PROG +c $SCRATCH_MNT/foo > > It's not so clear to me why writing into a compressed file is required, > would you please add more comments? The test is meant to test cases where we can deterministically make a direct IO write fallback to buffered IO. There are 2 such cases: 1) Attempting to write to an unaligned offset - this was the bug in 5.10 that resulted in a crash when CONFIG_BTRFS_ASSERT=y (default in many distros, such as openSUSE). 2) Writing to a range that has compressed extents. This has nothing to do with the 5.10 regression, I just added it since there's no existing test that explicitly and deterministically triggers this. So yes, I decided to add a test case for all possible cases of direct IO falling back to buffered instead of adding one just to test a regression (and help detecting any possible future regressions). Thanks. > > Thanks, > Eryu > > > + > > +$XFS_IO_PROG -s -c "pwrite -S 0xab -b 1M 0 1M" $SCRATCH_MNT/foo | > > _filter_xfs_io > > +# Now do the direct IO write... > > +$XFS_IO_PROG -d -s -c "pwrite -S 0xcd 512K 512K" $SCRATCH_MNT/foo | > > _filter_xfs_io > > + > > +# Now try doing a write into an unaligned offset... > > +$XFS_IO_PROG -f -d -s -c "pwrite -S 0xef 1111 512K" $SCRATCH_MNT/bar | > > _filter_xfs_io > > + > > +# Unmount, mount again, and verify we have the expected data. > > +_scratch_cycle_mount > > + > > +echo "File foo data:" > > +od -A d -t x1 $SCRATCH_MNT/foo > > +echo "File bar data:" > > +od -A d -t x1 $SCRATCH_MNT/bar > > + > > +status=0 > > +exit > > diff --git a/tests/btrfs/231.out b/tests/btrfs/231.out > > new file mode 100644 > > index 00000000..def05769 > > --- /dev/null > > +++ b/tests/btrfs/231.out > > @@ -0,0 +1,21 @@ > > +QA output created by 231 > > +wrote 1048576/1048576 bytes at offset 0 > > +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > > +wrote 524288/524288 bytes at offset 524288 > > +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > > +wrote 524288/524288 bytes at offset 1111 > > +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > > +File foo data: > > +0000000 ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab > > +* > > +0524288 cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd > > +* > > +1048576 > > +File bar data: > > +0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > +* > > +0001104 00 00 00 00 00 00 00 ef ef ef ef ef ef ef ef ef > > +0001120 ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef > > +* > > +0525392 ef ef ef ef ef ef ef > > +0525399 > > diff --git a/tests/btrfs/group b/tests/btrfs/group > > index a7c65983..9f63db69 100644 > > --- a/tests/btrfs/group > > +++ b/tests/btrfs/group > > @@ -233,3 +233,4 @@ > > 228 auto quick volume > > 229 auto quick send clone > > 230 auto quick qgroup limit > > +231 auto quick compress rw > > -- > > 2.28.0
