[PATCH v2 1/3] f2fs/018: check data eof after partial truncation on compressed cluster

[Chao Yu <chao@kernel.org>]

This is a regression testcase, it is added to check below case
and its variants:
- write 16k data into compressed file (data will be compressed)
- truncate file to 12k (truncate partial data in compressed cluster)
- truncate file to 20k
- verify data in range of [12k, 16k] to see whether data is all zero
or not

Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
---
v2:
- add missing _require_xfs_io_command "truncate"
- add missing _require_fio $fio_config
- use $XFS_IO_PROG instead of xfs_io
- avoid mkfs&mount .. umount for each round test
 tests/f2fs/018     | 77 ++++++++++++++++++++++++++++++++++++++++++++++
 tests/f2fs/018.out |  2 ++
 2 files changed, 79 insertions(+)
 create mode 100755 tests/f2fs/018
 create mode 100644 tests/f2fs/018.out

diff --git a/tests/f2fs/018 b/tests/f2fs/018
new file mode 100755
index 00000000..e1047f78
--- /dev/null
+++ b/tests/f2fs/018
@@ -0,0 +1,77 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2025 Chao Yu.  All Rights Reserved.
+#
+# FS QA Test No. f2fs/018
+#
+# This is a regression test to check whether page eof will be
+# zero or not after we truncate partial data in compressed
+# cluster.
+#
+. ./common/preamble
+_begin_fstest auto quick rw compress
+
+_fixed_by_kernel_commit ba8dac350faf \
+	"f2fs: fix to zero post-eof page"
+_fixed_by_kernel_commit xxxxxxxxxxxx \
+	"f2fs: fix to zero data after EOF for compressed file correctly"
+
+_require_xfs_io_command "truncate"
+_require_scratch
+
+testfile=$SCRATCH_MNT/testfile
+fio_config=$tmp.fio
+
+cat >$fio_config <<EOF
+[global]
+filename=$testfile
+rw=read
+verify=pattern
+verify_pattern=0x00
+do_verify=1
+verify_only
+offset=0
+size=4k
+numjobs=1
+EOF
+_require_fio $fio_config
+
+_scratch_mkfs "-O extra_attr,compression" >> $seqres.full || _fail "mkfs failed"
+_scratch_mount "-o compress_extension=*" >> $seqres.full
+
+check_data_eof()
+{
+	local eof_start=$1
+	local eof_size=$2
+	local filesize=$3
+	local offset1=$4
+	local offset2=$5
+	local offset3=$6
+
+
+	$XFS_IO_PROG -f -c "pwrite 0 $filesize" -c "fsync" $testfile >> $seqres.full
+	$XFS_IO_PROG -c "truncate $offset1" $testfile
+	$XFS_IO_PROG -c "truncate $offset2" $testfile
+
+	if [ "$offset3" ]; then
+		xfs_io -c "truncate $offset3" $testfile
+	fi
+
+	$FIO_PROG --name=verify-data --filename=$testfile --rw=read --verify=pattern \
+		--verify_pattern=0x00 --do_verify=1 --verify_only --offset=$eof_start \
+		--size=$eof_size >> $seqres.full 2>&1 || _fail "eof data is not zero"
+
+	rm -f $testfile
+}
+
+check_data_eof 12k 4k 16k 12k 20k
+check_data_eof 10k 6k 16k 10k 20k
+check_data_eof 12k 4k 16k 8k 12k 20k
+check_data_eof 10k 6k 16k 8k 10k 20k
+
+_scratch_unmount
+
+echo "Silence is golden"
+
+status=0
+exit
diff --git a/tests/f2fs/018.out b/tests/f2fs/018.out
new file mode 100644
index 00000000..8849e303
--- /dev/null
+++ b/tests/f2fs/018.out
@@ -0,0 +1,2 @@
+QA output created by 018
+Silence is golden
-- 
2.49.0