#! /bin/bash
# FS QA Test No. 173
#
# Reflink a file, use up the rest of the space, then try to observe ENOSPC
# while copy-on-writing the file via mmap.
#
#-----------------------------------------------------------------------
# Copyright (c) 2015, Oracle and/or its affiliates.  All Rights Reserved.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
#-----------------------------------------------------------------------

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 -rf $tmp.* $testdir1
}

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

# real QA test starts here
_supported_os Linux
_require_scratch_reflink
_require_cp_reflink

rm -f $seqres.full

echo "Format and mount"
_scratch_mkfs > $seqres.full 2>&1
_scratch_mount >> $seqres.full 2>&1

testdir=$SCRATCH_MNT/test-$seq
mkdir $testdir

echo "Reformat with appropriate size"
blksz="$(stat -f $testdir -c '%S')"
nr_blks=10240
umount $SCRATCH_MNT
sz_bytes=$((nr_blks * 8 * blksz))
if [ $sz_bytes -lt $((32 * 1048576)) ]; then
	sz_bytes=$((32 * 1048576))
fi
_scratch_mkfs_sized $sz_bytes >> $seqres.full 2>&1
_scratch_mount >> $seqres.full 2>&1
rm -rf $testdir
mkdir $testdir

echo "Create a big file and reflink it"
_pwrite_byte 0x61 0 $((blksz * nr_blks)) $testdir/bigfile >> $seqres.full 2>&1
_cp_reflink $testdir/bigfile $testdir/clonefile
sync

echo "Allocate the rest of the space"
nr_free=$(stat -f -c '%f' $testdir)
touch $testdir/file0 $testdir/file1
_pwrite_byte 0x61 0 $((blksz * nr_free)) $testdir/eat_my_space >> $seqres.full 2>&1
sync

echo "mmap CoW the big file"
out="$(_mwrite_byte 0x62 0 $((blksz * nr_blks)) $((blksz * nr_blks)) $testdir/bigfile 2>&1)"
err="$?"
if [ $err -lt 128 ]; then
	echo "mmap CoW should have failed with SIGBUS, got SIG$(kill -l $err)"
fi

echo "Remount and try CoW again"
_scratch_cycle_mount

out="$(_mwrite_byte 0x62 0 $((blksz * nr_blks)) $((blksz * nr_blks)) $testdir/bigfile 2>&1)"
err="$?"
if [ $err -lt 128 ]; then
	echo "mmap CoW should have failed with SIGBUS, got SIG$(kill -l $err)"
fi

# success, all done
status=0
exit
