Re: [PATCH v3] xfs: add a test for number of open zones on conventional devices

On Tue, Apr 14, 2026 at 09:55:47AM +0200, Christoph Hellwig wrote:
> Test that mounts of zoned file systems on conventional devices don't
> create more open zones than allowed when the last blocks in one or more
> zones have been invalidated.
> 
> Signed-off-by: Christoph Hellwig <[email protected]>
> ---
> 
> Changes since v2:
>  - use raw mkfs to avoid injecting a real RT device
>  - _notrun with a useful message when the mkfs or mount fails due to lack
>    of RT device or zoned block device support
> 
>  tests/xfs/4201     | 69 ++++++++++++++++++++++++++++++++++++++++++++++
>  tests/xfs/4201.out |  1 +
>  2 files changed, 70 insertions(+)
>  create mode 100755 tests/xfs/4201
>  create mode 100644 tests/xfs/4201.out
> 
> diff --git a/tests/xfs/4201 b/tests/xfs/4201
> new file mode 100755
> index 000000000000..56084bca41c0
> --- /dev/null
> +++ b/tests/xfs/4201
> @@ -0,0 +1,69 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2026 Christoph Hellwig.
> +#
> +# FS QA Test No. 4201
> +#
> +# Test that mounts of zoned file systems on conventional devices don't create
> +# more open zones than allowed when the last blocks in one or more zones have
> +# been invalidated.
> +#
> +
> +. ./common/preamble
> +_begin_fstest auto quick zone
> +
> +_require_scratch_nocheck
> +_require_odirect
> +_require_non_zoned_device $SCRATCH_DEV
> +_require_non_zoned_device $SCRATCH_RTDEV

Seems fine to me still, though I wonder if you still need to check
SCRATCH_RTDEV if you're opencoding the mkfs/mount calls?

Reviewed-by: "Darrick J. Wong" <[email protected]>

--D

> +
> +open_zones=5
> +blocks=16384
> +bsize=4096
> +
> +zone_size_mib=$((blocks * bsize / 1024 / 1024))
> +file_size_mib=$((zone_size_mib / 2))
> +nr_files=$((open_zones * 3 - 1))
> +
> +echo "zone size: $zone_size_mib" >>$seqres.full
> +echo "file size: $file_size_mib" >>$seqres.full
> +echo "nr files: $nr_files" >>$seqres.full
> +
> +# don't use _scratch_mkfs/_scratch_mount to avoid injection a real RT device
> +$MKFS_XFS_PROG -b size=${bsize} -r zoned=1,rgsize=${blocks}b \
> +	$SCRATCH_DEV > "$seqres.full" 2>&1 || \
> +		_notrun "Zoned mkfs not supported"
> +_mount $SCRATCH_DEV $SCRATCH_MNT -o max_open_zones=${open_zones} || \
> +	_notrun "Zoned allocator not supported"
> +
> +_has_fs_sysfs_attr $SCRATCH_DEV zoned/nr_open_zones || \
> +	_notrun "This test requires /sys/fs/${FSTYP}/$SCRATCH_DEV/zoned/nr_open_zones"
> +
> +for i in $(seq 1 $nr_files); do
> +	dd if=/dev/zero of=$SCRATCH_MNT/$i bs=1M count=$file_size_mib \
> +		 oflag=direct > /dev/null 2>&1
> +done
> +
> +# delete odd numbered files as they should be at the end of the zones
> +for ((i = 0; i < $nr_files; i = $((i + 2)))); do
> +	rm $SCRATCH_MNT/$((i + 1))
> +done
> +
> +_scratch_unmount
> +_mount $SCRATCH_DEV $SCRATCH_MNT -o max_open_zones=${open_zones}
> +
> +max_open=$(_get_fs_sysfs_attr $SCRATCH_DEV zoned/max_open_zones)
> +nr_open=$(_get_fs_sysfs_attr $SCRATCH_DEV zoned/nr_open_zones)
> +
> +if [ ${max_open} -ne $((open_zones - 1)) ]; then
> +	_fail "Test needs adjustments for multiple open GC zones"
> +fi
> +
> +if [ ${nr_open} -gt ${max_open} ]; then
> +	_fail "Too many open zones: $nr_open/$max_open"
> +fi
> +
> +_scratch_unmount
> +
> +status=0
> +exit
> diff --git a/tests/xfs/4201.out b/tests/xfs/4201.out
> new file mode 100644
> index 000000000000..32e395dd4d6d
> --- /dev/null
> +++ b/tests/xfs/4201.out
> @@ -0,0 +1 @@
> +QA output created by 4201
> -- 
> 2.53.0
> 
>