Re: [PATCH v8 11/13] fstests: verify exportfs file handles on cloned filesystems

[Zorro Lang <zlang@kernel.org>]

On Sat, Jul 25, 2026 at 03:39:08PM +0800, Anand Jain wrote:
> Ensure that exportfs can correctly decode file handles on a cloned
> filesystem across a mount cycle, by file handles generated on a
> cloned device remain valid after mount cycle.
> 
> Signed-off-by: Anand Jain <asj@kernel.org>
> ---
>  tests/generic/805     | 80 +++++++++++++++++++++++++++++++++++++++++++
>  tests/generic/805.out |  2 ++
>  2 files changed, 82 insertions(+)
>  create mode 100644 tests/generic/805
>  create mode 100644 tests/generic/805.out
> 
> diff --git a/tests/generic/805 b/tests/generic/805
> new file mode 100644
> index 000000000000..5827eee039df
> --- /dev/null
> +++ b/tests/generic/805
> @@ -0,0 +1,80 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2026 Anand Jain <asj@kernel.org>.  All Rights Reserved.
> +#
> +# FS QA Test No. 805
> +# Verify that file handles encoded on a cloned filesystem remain valid and
> +# resolvable via open_by_handle across a mount cycle and mount order swap.
> +
> +. ./common/preamble
> +
> +_begin_fstest auto quick exportfs clone
> +
> +_require_test
> +_require_block_device $TEST_DEV
> +_require_exportfs
> +_require_loop
> +_require_test_program "open_by_handle"
> +
> +_cleanup()
> +{
> +	cd /
> +	rm -r -f $tmp.*
> +	_unmount $mnt1 2>/dev/null
> +	_unmount $mnt2 2>/dev/null
> +	_loop_image_destroy "${devs[@]}" 2> /dev/null
> +}
> +
> +# Create test dir and test files, encode file handles and store to tmp file
> +create_test_files()
> +{
> +	rm -rf $testdir
> +	mkdir -p $testdir
> +	$here/src/open_by_handle -cwp -o $tmp.handles_file $testdir $NUMFILES
> +}
> +
> +# Attempt to read and decode the saved file handles on the targeted mount point.
> +test_file_handles()
> +{
> +	local opt=$1
> +	local when=$2
> +
> +	echo test_file_handles after $when
> +	$here/src/open_by_handle $opt -i $tmp.handles_file $mnt2 $NUMFILES
> +}
> +
> +# Setup base loop device and its clone
> +devs=()
> +_loop_image_create_clone devs
> +mkdir -p $TEST_DIR/$seq
> +mnt1=$TEST_DIR/$seq/mnt1
> +mnt2=$TEST_DIR/$seq/mnt2
> +mkdir -p $mnt1
> +mkdir -p $mnt2
> +
> +# Mount both identical UUID filesystems simultaneously
> +_mount $(_common_dev_mount_options) $(_clone_mount_option) ${devs[0]} $mnt1 || \
> +						_fail "Failed to mount dev1"
> +_mount $(_common_dev_mount_options) $(_clone_mount_option) ${devs[1]} $mnt2 || \
> +						_fail "Failed to mount dev2"
> +
> +NUMFILES=1

NUMFILES=${LOAD_FACTOR} ?

> +testdir=$mnt2/testdir
> +
> +# Decode file handles of files/dir after cycle mount
> +create_test_files
> +
> +# Cycle mounts and reverse initialization sequence to check if
> +# file handle lookups are okay
> +_unmount $mnt1
> +_unmount $mnt2
> +_mount $(_common_dev_mount_options) $(_clone_mount_option) ${devs[1]} $mnt2 || \
> +						_fail "Failed to mount dev2"
> +_mount $(_common_dev_mount_options) $(_clone_mount_option) ${devs[0]} $mnt1 || \
> +						_fail "Failed to mount dev1"
> +
> +# Verify file handles can still be resolved post-mount-cycle
> +test_file_handles -rp "cycle mount"
> +
> +status=0
> +exit
> diff --git a/tests/generic/805.out b/tests/generic/805.out
> new file mode 100644
> index 000000000000..29b11ec77ffb
> --- /dev/null
> +++ b/tests/generic/805.out
> @@ -0,0 +1,2 @@
> +QA output created by 805
> +test_file_handles after cycle mount
> -- 
> 2.43.0
>