#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2018 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test 167
#
# Test if btrfs will corrupt compressed data extent without data csum
# by replacing it with uncompressed data, when doing device replace.
#
# This could be fixed by the following kernel commit:
# ac0b4145d662 ("btrfs: scrub: Don't use inode pages for device replace")
#
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"

here=`pwd`
tmp=/tmp/$$
status=1	# failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15

_cleanup()
{
	cd /
	rm -f $tmp.*
}

# get standard environment, filters and checks
. ./common/rc
. ./common/filter

# remove previous $seqres.full before test
rm -f $seqres.full

# real QA test starts here

# Modify as appropriate.
_supported_fs btrfs
_supported_os Linux
_require_scratch_dev_pool 2
_require_scratch_dev_pool_equal_size

_scratch_dev_pool_get 1
_spare_dev_get
_scratch_pool_mkfs >> $seqres.full 2>&1

# Create nodatasum inode
_scratch_mount "-o nodatasum"
touch $SCRATCH_MNT/nodatasum_file
_scratch_remount "datasum,compress"
_pwrite_byte 0xcd 0 128K $SCRATCH_MNT/nodatasum_file > /dev/null

# Write the compressed data back to disk
sync

# Replace the device
_run_btrfs_util_prog replace start -Bf 1 $SPARE_DEV $SCRATCH_MNT

# Unmount to drop all cache so next read will read from disk
_scratch_unmount
_mount $SPARE_DEV $SCRATCH_MNT

# Now the EXTENT_DATA item still marks the extent as compressed,
# but the on-disk data is uncompressed, thus reading it as compressed
# will definitely cause EIO.
cat $SCRATCH_MNT/nodatasum_file > /dev/null

_scratch_unmount
_spare_dev_put
_scratch_dev_pool_put

echo "Silence is golden"

# success, all done
status=0
exit
