tests/btrfs/013

#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2013 Fusion IO.  All Rights Reserved.
#
# FS QA Test No. btrfs/013
#
# Regression test for balance with prealloc extents.  This checks to make sure
# we are balacing prealloc'ed extents properly by making sure we don't have any
# csum errors.  Unfortunately this manifests itself with no csum which means
# userspace doesn't get an error when reading the file back so we have to grok
# dmesg to see if there was a csum error.
#
. ./common/preamble
_begin_fstest auto quick balance prealloc

. ./common/filter

_require_scratch
_require_xfs_io_command "falloc"

_scratch_mkfs > /dev/null 2>&1
_scratch_mount

nr_csum_no_found=$(dmesg | grep -c "no csum found")
nr_csum_failed=$(dmesg | grep -c "csum failed")

_check_csum_error()
{
	new_csum_no_found=$(dmesg | grep -c "no csum found")
	new_csum_failed=$(dmesg | grep -c "csum failed")

	if [ $nr_csum_no_found -eq $new_csum_no_found -a \
	     $nr_csum_failed -eq $new_csum_failed ]; then
		return 0
	fi
	return 1
}
$XFS_IO_PROG -f -c "falloc 0 1M" -c "pwrite 16k 8k" -c "fsync" \
	$SCRATCH_MNT/foo > $seqres.full 2>&1
_run_btrfs_balance_start $SCRATCH_MNT >> $seqres.full
_scratch_unmount
_scratch_mount
$XFS_IO_PROG -c "pread 0 1M" $SCRATCH_MNT/foo >> $seqres.full 2>&1 || \
	_fail "pread failed"

# This sucks but unfortunately it is the only way to be sure something didn't go
# wrong.
_check_csum_error || _fail "csum detected, please check dmesg"

echo "Silence is golden"
status=0 ; exit