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.bo...@bur.io/) Signed-off-by: Boris Burkov <bo...@bur.io> --- 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 + +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
