Re: [PATCH] generic: Verify if statx() can qurey S_SAX flag on regular file correctly

[Xiao Yang <yangx.jy@cn.fujitsu.com>]

Hi Ira, Darrick

I have one question about S_DAX flag:
Current statx() can only query S_DAX flag on regular file,
why don't we set S_DAX flag for directory in kernel? :-)

Best Regards,
Xiao Yang
On 2020/7/2 14:35, Xiao Yang wrote:
> With new kernel(e.g. v5.8-rc1), statx() can be used to qurey S_SAX flag
> on regular file, so add a test to verify the feature.
>
> Reference:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=712b2698e4c024b561694cbcc1abba13eb0fd9ce
>
> Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
> ---
>
> Note: this patch depends on the following patch set:
> https://www.spinics.net/lists/fstests/msg14252.html
>
>  tests/generic/604     | 100 ++++++++++++++++++++++++++++++++++++++++++
>  tests/generic/604.out |   2 +
>  tests/generic/group   |   1 +
>  3 files changed, 103 insertions(+)
>  create mode 100644 tests/generic/604
>  create mode 100644 tests/generic/604.out
>
> diff --git a/tests/generic/604 b/tests/generic/604
> new file mode 100644
> index 00000000..b0baa781
> --- /dev/null
> +++ b/tests/generic/604
> @@ -0,0 +1,100 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2020 Fujitsu.  All Rights Reserved.
> +#
> +# FS QA Test 604
> +#
> +# By the following cases, verify if statx() can query S_SAX flag
> +# on regular file correctly.
> +# 1) With dax=always option, FS_XFLAG_DAX is ignored and S_SAX flag
> +#    always exists on regular file.
> +# 2) With dax=inode option, setting/clearing FS_XFLAG_DAX can change
> +#    S_SAX flag on regular file.
> +# 3) With dax=never option, FS_XFLAG_DAX is ignored and S_SAX flag
> +#    never exists on regular file.
> +#
> +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.*
> +}
> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +
> +# remove previous $seqres.full before test
> +rm -f $seqres.full
> +
> +_supported_fs generic
> +_supported_os Linux
> +_require_scratch_dax_mountopt "dax=always"
> +_require_scratch_dax_iflag
> +_require_xfs_io_command "statx" "-r"
> +
> +PARENT_DIR=$SCRATCH_MNT/testdir
> +TEST_FILE=$PARENT_DIR/testfile
> +
> +check_s_dax()
> +{
> +	local exp_s_dax=$1
> +
> +	local attributes=$($XFS_IO_PROG -c 'statx -r' $TEST_FILE | awk '/stat.attributes / { print $3 }')
> +	if [ $exp_s_dax -eq 0 ]; then
> +		(( attributes & 0x2000 )) && echo "$TEST_FILE has unexpected S_DAX flag"
> +	else
> +		(( attributes & 0x2000 )) || echo "$TEST_FILE doen't have expected S_DAX flag"
> +	fi
> +}
> +
> +test_s_dax()
> +{
> +	local dax_option=$1
> +	local exp_s_dax1=$2
> +	local exp_s_dax2=$3
> +
> +	# Mount with specified dax option
> +	_scratch_mount "-o $dax_option"
> +
> +	# Prepare directory
> +	mkdir -p $PARENT_DIR
> +
> +	rm -f $TEST_FILE
> +	$XFS_IO_PROG -c "chattr +x" $PARENT_DIR
> +	touch $TEST_FILE
> +	# Check if setting FS_XFLAG_DAX changes S_DAX flag
> +	check_s_dax $exp_s_dax1
> +
> +	rm -f $TEST_FILE
> +	$XFS_IO_PROG -c "chattr -x" $PARENT_DIR
> +	touch $TEST_FILE
> +	# Check if clearing FS_XFLAG_DAX changes S_DAX flag
> +	check_s_dax $exp_s_dax2
> +
> +	_scratch_unmount
> +}
> +
> +do_tests()
> +{
> +	test_s_dax "dax=always" 1 1
> +	test_s_dax "dax=inode" 1 0
> +	test_s_dax "dax=never" 0 0
> +}
> +
> +_scratch_mkfs >> $seqres.full 2>&1
> +
> +do_tests
> +
> +# success, all done
> +echo "Silence is golden"
> +status=0
> +exit
> diff --git a/tests/generic/604.out b/tests/generic/604.out
> new file mode 100644
> index 00000000..c06a1c7f
> --- /dev/null
> +++ b/tests/generic/604.out
> @@ -0,0 +1,2 @@
> +QA output created by 604
> +Silence is golden
> diff --git a/tests/generic/group b/tests/generic/group
> index 1d0d5606..676e0d2e 100644
> --- a/tests/generic/group
> +++ b/tests/generic/group
> @@ -606,3 +606,4 @@
>  601 auto quick quota
>  602 auto quick encrypt
>  603 auto attr quick dax
> +604 auto attr quick dax