#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2020 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test 215
#
# Test that reading corrupted files would correctly increment device status
# counters. This is fixed by the following linux kernel commit:
# 814723e0a55a ("btrfs: increment device corruption error in case of checksum error")
#
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
get_physical()
{
	$BTRFS_UTIL_PROG inspect-internal dump-tree -t 3 $SCRATCH_DEV | \
		grep $1 -A2 | \
		$AWK_PROG "(\$1 ~ /stripe/ && \$3 ~ /devid/ && \$2 ~ /0/) { print \$6 }"
}

# Modify as appropriate.
_supported_fs btrfs

_scratch_mkfs > /dev/null
# disable freespace inode to ensure file is the first thing in the data
# blobk group
_scratch_mount -o nospace_cache

blocksize=$(_get_block_size $SCRATCH_MNT)
filesize=$((8*$blocksize))
uuid=$(findmnt -n -o UUID "$SCRATCH_MNT")

if [ ! -e /sys/fs/btrfs/$uuid/bdi ]; then
	_notrun "bdi link not found"
fi

#create an 8 block file
$XFS_IO_PROG -d -f -c "pwrite -S 0xbb -b $filesize 0 $filesize" "$SCRATCH_MNT/foobar" > /dev/null

logical_extent=$($FILEFRAG_PROG -v "$SCRATCH_MNT/foobar" | _filter_filefrag | cut -d '#' -f 1)
physical_extent=$(get_physical $logical_extent)

echo "logical = $logical_extent physical=$physical_extent" >> $seqres.full

# corrupt first 4 blocks of file
_scratch_unmount
$XFS_IO_PROG -d -c "pwrite -S 0xaa -b $blocksize $physical_extent $((4*$blocksize))" $SCRATCH_DEV > /dev/null
_scratch_mount

# disable readahead to avoid skewing the counter
echo 0 > /sys/fs/btrfs/$uuid/bdi/read_ahead_kb

# buffered reads whould result in 2 errors since readahead code always submits
# at least 1 page worth of IO and it will be counted as an error as well
$XFS_IO_PROG -c "pread -b $filesize 0 $filesize" "$SCRATCH_MNT/foobar" > /dev/null 2>&1
errs=$($BTRFS_UTIL_PROG device stats $SCRATCH_DEV | awk '/corruption_errs/ { print $2 }')
if [ $errs -ne 2 ]; then
	_fail "Errors: $errs expected: 2"
fi

# DIO does check every sector
$XFS_IO_PROG -d -c "pread -b $filesize 0 $filesize" "$SCRATCH_MNT/foobar" > /dev/null 2>&1
errs=$($BTRFS_UTIL_PROG device stats $SCRATCH_DEV | awk '/corruption_errs/ { print $2 }')
if [ $errs -ne 6 ]; then
	_fail "Errors: $errs expected: 6"
fi

# success, all done
echo "Silence is golden"
status=0
exit