[PATCH blktests v4 2/2] md: add regression test for "md/md-bitmap: fix writing non bitmap pages"

[Paul Menzel]

Dear Ofir,


Thank you very much for submitting a test case.

Am 21.07.24 um 09:11 schrieb Ofir Gal:
> A bug in md-bitmap has been discovered by setting up a md raid on top of
> nvme-tcp devices that has optimal io size larger than the allocated
> bitmap.
> 
> The following test reproduce the bug by setting up a md-raid on top of

reproduce*s*

> nvme-tcp device over ram device that sets the optimal io size by using
> dm-stripe.

For people ignorant of the test infrastructure, maybe add a line how to 
run this one test, and maybe even paste the output of the failed test.


Kind regards,

Paul


> Signed-off-by: Ofir Gal <ofir.gal at volumez.com>
> ---
>   common/brd       | 28 ++++++++++++++++
>   tests/md/001     | 86 ++++++++++++++++++++++++++++++++++++++++++++++++
>   tests/md/001.out |  3 ++
>   tests/md/rc      | 13 ++++++++
>   4 files changed, 130 insertions(+)
>   create mode 100644 common/brd
>   create mode 100755 tests/md/001
>   create mode 100644 tests/md/001.out
>   create mode 100644 tests/md/rc
> 
> diff --git a/common/brd b/common/brd
> new file mode 100644
> index 0000000..31e964f
> --- /dev/null
> +++ b/common/brd
> @@ -0,0 +1,28 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-3.0+
> +# Copyright (C) 2024 Ofir Gal
> +#
> +# brd helper functions
> +
> +. common/shellcheck
> +
> +_have_brd() {
> +	_have_module brd
> +}
> +
> +_init_brd() {
> +	# _have_brd loads brd, we need to wait a bit for brd to be not in use in
> +	# order to reload it
> +	sleep 0.2
> +
> +	if ! modprobe -r brd || ! modprobe brd "$@" ; then
> +		echo "failed to reload brd with args: $*"
> +		return 1
> +	fi
> +
> +	return 0
> +}
> +
> +_cleanup_brd() {
> +	modprobe -r brd
> +}
> diff --git a/tests/md/001 b/tests/md/001
> new file mode 100755
> index 0000000..5c8c59a
> --- /dev/null
> +++ b/tests/md/001
> @@ -0,0 +1,86 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-3.0+
> +# Copyright (C) 2024 Ofir Gal
> +#
> +# The bug is "visible" only when the underlying device of the raid is a network
> +# block device that utilize MSG_SPLICE_PAGES. nvme-tcp is used as the network device.
> +#
> +# Regression test for patch "md/md-bitmap: fix writing non bitmap pages" and
> +# for patch "nvme-tcp: use sendpages_ok() instead of sendpage_ok()"
> +
> +. tests/md/rc
> +. common/brd
> +. common/nvme
> +
> +DESCRIPTION="Raid with bitmap on tcp nvmet with opt-io-size over bitmap size"
> +QUICK=1
> +
> +#restrict test to nvme-tcp only
> +nvme_trtype=tcp
> +nvmet_blkdev_type="device"
> +
> +requires() {
> +	# Require dm-stripe
> +	_have_program dmsetup
> +	_have_driver dm-mod
> +	_have_driver raid1
> +
> +	_require_nvme_trtype tcp
> +	_have_brd
> +}
> +
> +# Sets up a brd device of 1G with optimal-io-size of 256K
> +setup_underlying_device() {
> +	if ! _init_brd rd_size=1048576 rd_nr=1; then
> +		return 1
> +	fi
> +
> +	dmsetup create ram0_big_optio --table \
> +		"0 $(blockdev --getsz /dev/ram0) striped 1 512 /dev/ram0 0"
> +}
> +
> +cleanup_underlying_device() {
> +	dmsetup remove ram0_big_optio
> +	_cleanup_brd
> +}
> +
> +# Sets up a local host nvme over tcp
> +setup_nvme_over_tcp() {
> +	_setup_nvmet
> +
> +	local port
> +	port="$(_create_nvmet_port "${nvme_trtype}")"
> +
> +	_create_nvmet_subsystem "${def_subsysnqn}" "/dev/mapper/ram0_big_optio" "${def_subsys_uuid}"
> +	_add_nvmet_subsys_to_port "${port}" "${def_subsysnqn}"
> +
> +	_create_nvmet_host "${def_subsysnqn}" "${def_hostnqn}"
> +
> +	_nvme_connect_subsys
> +}
> +
> +cleanup_nvme_over_tcp() {
> +	_nvme_disconnect_subsys
> +	_nvmet_target_cleanup --subsysnqn "${def_subsysnqn}"
> +}
> +
> +test() {
> +	echo "Running ${TEST_NAME}"
> +
> +	setup_underlying_device
> +	setup_nvme_over_tcp
> +
> +	local ns
> +	ns=$(_find_nvme_ns "${def_subsys_uuid}")
> +
> +	# Hangs here without the fix
> +	mdadm --quiet --create /dev/md/blktests_md --level=1 --bitmap=internal \
> +		--bitmap-chunk=1024K --assume-clean --run --raid-devices=2 \
> +		/dev/"${ns}" missing
> +
> +	mdadm --quiet --stop /dev/md/blktests_md
> +	cleanup_nvme_over_tcp
> +	cleanup_underlying_device
> +
> +	echo "Test complete"
> +}
> diff --git a/tests/md/001.out b/tests/md/001.out
> new file mode 100644
> index 0000000..23071ec
> --- /dev/null
> +++ b/tests/md/001.out
> @@ -0,0 +1,3 @@
> +Running md/001
> +disconnected 1 controller(s)
> +Test complete
> diff --git a/tests/md/rc b/tests/md/rc
> new file mode 100644
> index 0000000..96bcd97
> --- /dev/null
> +++ b/tests/md/rc
> @@ -0,0 +1,13 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-3.0+
> +# Copyright (C) 2024 Ofir Gal
> +#
> +# Tests for md raid
> +
> +. common/rc
> +
> +group_requires() {
> +	_have_root
> +	_have_program mdadm
> +	_have_driver md-mod
> +}