From: Filipe Manana <fdmanana@xxxxxxxx>
Test that if we fsync a file that has no more hard links, power fail and
then mount the filesystem, after the journal/log is replayed, the file
doesn't exists anymore.
This exercises a bug recently found and fixed by the following patch for
the linux kernel:
btrfs: fix fsync of files with no hard links not persisting deletion
Signed-off-by: Filipe Manana <fdmanana@xxxxxxxx>
---
tests/generic/764 | 78 +++++++++++++++++++++++++++++++++++++++++++
tests/generic/764.out | 2 ++
2 files changed, 80 insertions(+)
create mode 100755 tests/generic/764
create mode 100644 tests/generic/764.out
diff --git a/tests/generic/764 b/tests/generic/764
new file mode 100755
index 00000000..57d21095
--- /dev/null
+++ b/tests/generic/764
@@ -0,0 +1,78 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2025 SUSE Linux Products GmbH. All Rights Reserved.
+#
+# FS QA Test 764
+#
+# Test that if we fsync a file that has no more hard links, power fail and then
+# mount the filesystem, after the journal/log is replayed, the file doesn't
+# exists anymore.
+#
+. ./common/preamble
+_begin_fstest auto quick log
+
+_cleanup()
+{
+ if [ ! -z $XFS_IO_PID ]; then
+ kill $XFS_IO_PID > /dev/null 2>&1
+ wait $XFS_IO_PID > /dev/null 2>&1
+ fi
+ _cleanup_flakey
+ cd /
+ rm -r -f $tmp.*
+}
+
+. ./common/dmflakey
+
+[ "$FSTYP" = "btrfs" ] && _fixed_by_kernel_commit xxxxxxxxxxxx \
+ "btrfs: fix fsync of files with no hard links not persisting deletion"
+
+_require_scratch
+_require_dm_target flakey
+_require_mknod
+
+_scratch_mkfs >>$seqres.full 2>&1 || _fail "mkfs failed"
+_require_metadata_journaling $SCRATCH_DEV
+_init_flakey
+_mount_flakey
+
+touch $SCRATCH_MNT/foo
+
+# Commit the current transaction and persist the file.
+_scratch_sync
+
+# A fifo to communicate with a background xfs_io process that will fsync the
+# file after we deleted its hard link while it's open by xfs_io.
+mkfifo $SCRATCH_MNT/fifo
+
+tail -f $SCRATCH_MNT/fifo | $XFS_IO_PROG $SCRATCH_MNT/foo >>$seqres.full &
+XFS_IO_PID=$!
+
+# Give some time for the xfs_io process to open a file descriptor for the file.
+sleep 1
+
+# Now while the file is open by the xfs_io process, delete its only hard link.
+rm -f $SCRATCH_MNT/foo
+
+# Now that it has no more hard links, make the xfs_io process fsync it.
+echo "fsync" > $SCRATCH_MNT/fifo
+
+# Terminate the xfs_io process so that we can unmount.
+echo "quit" > $SCRATCH_MNT/fifo
+wait $XFS_IO_PID
+unset XFS_IO_PID
+
+# Simulate a power failure and then mount again the filesystem to replay the
+# journal/log.
+_flakey_drop_and_remount
+
+# We don't expect the file to exist anymore, since it was fsynced when it had no
+# more hard links.
+[ -f $SCRATCH_MNT/foo ] && echo "file foo still exists"
+
+_unmount_flakey
+
+# success, all done
+echo "Silence is golden"
+status=0
+exit
diff --git a/tests/generic/764.out b/tests/generic/764.out
new file mode 100644
index 00000000..bb58e5b8
--- /dev/null
+++ b/tests/generic/764.out
@@ -0,0 +1,2 @@
+QA output created by 764
+Silence is golden
--
2.45.2
