On Wed, Apr 07, 2021 at 01:13:26PM -0700, Boris Burkov wrote: > btrfs trims fiemap extents to the inputted offset, which leads to > inconsistent results for most inputs, and downright bizarre outputs like > [7..6] when the trimmed extent is at the end of an extent and shorter > than 512 bytes. > > The test writes out one extent of the file system's block size and tries > fiemaps at various offsets. It expects that all the fiemaps return the > full single extent. > > I ran it under the following fs, block size combinations: > ext2: 1024, 2048, 4096 > ext3: 1024, 2048, 4096 > ext4: 1024, 2048, 4096 > xfs: 512, 1024, 2048, 4096 > f2fs: 4096 > btrfs: 4096 > > This test is fixed for btrfs by: > btrfs: return whole extents in fiemap > (https://lore.kernel.org/linux-btrfs/274e5bcebdb05a8969fc300b4802f33da2fbf218.1617746680.git.boris@xxxxxx/) > > Signed-off-by: Boris Burkov <boris@xxxxxx> generic/473, which tests fiemap, has been marked as broken, as fiemap behavior is not consistent across filesystems, and the specific behavior tested by generic/473 is not defined and filesystems could have different implementations. I'm not sure if this test fits into the undefined-behavior fiemap categary. I think it's fine if it tests a well-defined & consistent behavior. > --- > v3: make the block size more generic, use test dev instead of scratch, > cleanup style issues. > v2: fill out copyright and test description > --- > tests/generic/623 | 94 +++++++++++++++++++++++++++++++++++++++++++ > tests/generic/623.out | 2 + > tests/generic/group | 1 + > 3 files changed, 97 insertions(+) > create mode 100755 tests/generic/623 > create mode 100644 tests/generic/623.out > > diff --git a/tests/generic/623 b/tests/generic/623 > new file mode 100755 > index 00000000..a5ef369a > --- /dev/null > +++ b/tests/generic/623 > @@ -0,0 +1,94 @@ > +#! /bin/bash > +# SPDX-License-Identifier: GPL-2.0 > +# Copyright (c) 2021 Facebook. All Rights Reserved. > +# > +# FS QA Test 623 > +# > +# Test fiemaps with offsets into small parts of extents. > +# Expect to get the whole extent, anyway. > +# > +seq=`basename $0` > +seqres=$RESULT_DIR/$seq > +echo "QA output created by $seq" > + > +here=`pwd` > +tmp=/tmp/$$ > +status=1 # failure is the default! > +trap "_cleanup; exit \$status" 0 1 2 3 15 > + > +_cleanup() > +{ > + cd / > + rm -f $tmp.* > + rm -f $fiemap_file > +} > + > +# get standard environment, filters and checks > +. ./common/rc > +. ./common/filter > + > +# remove previous $seqres.full before test > +rm -f $seqres.full > + > +# real QA test starts here > + > +# Modify as appropriate. > +_supported_fs generic > +_require_test > +_require_xfs_io_command "fiemap" > + > +rm -f $seqres.full > + > +fiemap_file=$TEST_DIR/foo.$$ > + > +do_fiemap() { > + off=$1 > + len=$2 > + echo $off $len >> $seqres.full > + $XFS_IO_PROG -c "fiemap $off $len" $fiemap_file | tee -a $seqres.full > +} > + > +check_fiemap() { > + off=$1 > + len=$2 > + actual=$(do_fiemap $off $len) > + [ "$actual" == "$expected" ] || _fail "unexpected fiemap on $off $len" > +} > + > +# write a file with one extent > +block_size=$(_get_block_size $TEST_DIR) > +$XFS_IO_PROG -f -s -c "pwrite -S 0xcf 0 $block_size" $fiemap_file >/dev/null > + > +# since the exact extent location is unpredictable especially when > +# varying file systems, just test that they are all equal, which is > +# what we really expect. > +expected=$(do_fiemap) > + > +mid=$((block_size / 2)) > +almost=$((block_size - 5)) > +past=$((block_size + 1)) > + > +check_fiemap 0 $mid > +check_fiemap 0 $block_size > +check_fiemap 0 $past > +check_fiemap $mid $almost > +check_fiemap $mid $block_size > +check_fiemap $mid $past > +check_fiemap $almost 5 > +check_fiemap $almost 6 > + > +# fiemap output explicitly deals in 512 byte increments, > +# so exercise some cases where len is 512. > +# Naturally, some of these can't work if block size is 512. > +one_short=$((block_size - 512)) > +check_fiemap 0 512 > +check_fiemap $one_short 512 > +check_fiemap $almost 512 > + > +_test_unmount Any reason to umount TEST_DEV? Thanks, Eryu > + > +echo "Silence is golden" > + > +# success, all done > +status=0 > +exit > diff --git a/tests/generic/623.out b/tests/generic/623.out > new file mode 100644 > index 00000000..6f774f19 > --- /dev/null > +++ b/tests/generic/623.out > @@ -0,0 +1,2 @@ > +QA output created by 623 > +Silence is golden > diff --git a/tests/generic/group b/tests/generic/group > index b10fdea4..39e02383 100644 > --- a/tests/generic/group > +++ b/tests/generic/group > @@ -625,3 +625,4 @@ > 620 auto mount quick > 621 auto quick encrypt > 622 auto shutdown metadata atime > +623 auto quick > -- > 2.30.2
