#! /bin/bash
# FS QA Test No. 176
#
# See how well reflink handles reflinking a file with a million extents.
#
#-----------------------------------------------------------------------
# Copyright (c) 2016, 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".*
}

# 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
_require_test_program "punch-alternating"

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"

# Setup for one million blocks, but we'll accept stress testing down to
# 2^17 blocks... that should be plenty for anyone.
fnr=20
free_blocks=$(stat -f -c '%a' "$testdir")
blksz=$(_get_block_size "$testdir")
space_avail=$((free_blocks * blksz))
calc_space() {
	blocks_needed=$(( 2 ** (fnr + 1) ))
	space_needed=$((blocks_needed * blksz * 5 / 4))
}
calc_space
while test $space_needed -gt $space_avail; do
	fnr=$((fnr - 1))
	calc_space
done
test $fnr -lt 17 && _notrun "Insufficient space for stress test; would only create $blocks_needed extents."

echo "Create a many-block file"
echo "creating $blocks_needed blocks..." >> "$seqres.full"
$XFS_IO_PROG -f -c "pwrite -S 0x61 -b 4194304 0 $((2 ** (fnr + 1) * blksz))" "$testdir/file1" >> "$seqres.full"
echo "punching..." >> "$seqres.full"
"$here/src/punch-alternating" "$testdir/file1" >> "$seqres.full"
echo "...done" >> "$seqres.full"
_scratch_cycle_mount

echo "Reflink the big file"
bytes=$((blocks_needed * blksz))
echo "reflinking $((blocks_needed / 2)) blocks, $((bytes / 2)) bytes" >> "$seqres.full"
_reflink_range "$testdir/file1" 0 "$testdir/file2" 0 $bytes >> "$seqres.full"

# success, all done
status=0
exit