From 0a014baacc4c2a56728a94c6da272febccc1cceb Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Thu, 8 May 2025 07:34:40 +0200
Subject: [PATCH] xfs: test zoned ENOSPC behavior with multiple writers

Test that multiple parallel writers can't accidentally dip into the reserved
space pool.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Zorro Lang <zlang@kernel.org>
---
 tests/xfs/642     | 85 +++++++++++++++++++++++++++++++++++++++++++++++
 tests/xfs/642.out |  2 ++
 2 files changed, 87 insertions(+)
 create mode 100755 tests/xfs/642
 create mode 100644 tests/xfs/642.out

diff --git a/tests/xfs/642 b/tests/xfs/642
new file mode 100755
index 00000000..c5e51e5b
--- /dev/null
+++ b/tests/xfs/642
@@ -0,0 +1,85 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2024 Christoph Hellwig.
+#
+# FS QA Test No. 642
+#
+# Test that multiple parallel writers can't accidentally dip into the reserved
+# space pool.
+#
+. ./common/preamble
+_begin_fstest quick auto rw zone enospc
+
+. ./common/filter
+. ./common/zoned
+
+_require_scratch
+_require_odirect
+_require_aio
+
+_scratch_mkfs_sized $((256 * 1024 * 1024))  >>$seqres.full 2>&1
+
+# limit to two max open zones so that all writes get thrown into the blender
+export MOUNT_OPTIONS="$MOUNT_OPTIONS -o max_open_zones=2"
+_try_scratch_mount || _notrun "mount option not supported"
+_require_xfs_scratch_zoned
+
+fio_config=$tmp.fio
+
+cat >$fio_config <<EOF
+[global]
+bs=64k
+iodepth=16
+iodepth_batch=8
+directory=$SCRATCH_MNT
+ioengine=libaio
+rw=write
+direct=1
+size=60m
+
+[file1]
+filename=file1
+
+[file2]
+filename=file2
+
+[file3]
+filename=file3
+
+[file4]
+filename=file4
+
+[file5]
+filename=file5
+
+[file6]
+filename=file6
+
+[file7]
+filename=file7
+
+[file8]
+filename=file8
+EOF
+
+_require_fio $fio_config
+
+# try to overfill the file system
+$FIO_PROG $fio_config 2>&1 | \
+	grep -q "No space left on dev" || \
+	_fail "Overfill did not cause ENOSPC"
+
+sync
+
+#
+# Compare the df and du values to ensure we did not overshoot
+#
+# Use within_tolerance to paper over the fact that the du output includes
+# the root inode, which does not sit in the RT device, while df does not
+#
+df_val=`df --output=size $SCRATCH_MNT | tail -n 1`
+du_val=`du -s $SCRATCH_MNT | awk '{print $1}'`
+_within_tolerance "file space usage" $df_val $du_val 64 -v
+
+status=0
+exit
diff --git a/tests/xfs/642.out b/tests/xfs/642.out
new file mode 100644
index 00000000..e6b19b96
--- /dev/null
+++ b/tests/xfs/642.out
@@ -0,0 +1,2 @@
+QA output created by 642
+file space usage is in range
-- 
2.47.3