#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2017 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test No. btrfs/149
#
# Test that an incremental send/receive operation will not fail when the
# destination filesystem has compression enabled and the source filesystem
# has an extent at a file offset 0 that is not compressed and that is
# shared.
#
seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"

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

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

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

# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_test
_require_scratch
_require_scratch_reflink
_require_odirect
_require_btrfs_command inspect-internal dump-super

send_files_dir=$TEST_DIR/btrfs-test-$seq

rm -f $seqres.full
rm -fr $send_files_dir
mkdir $send_files_dir

_scratch_mkfs >>$seqres.full 2>&1
# On 64K pagesize systems the compression is more efficient, so max_inline
# helps to create regular (non inline) extent irrespective of the final
# write size.
_scratch_mount "-o compress -o max_inline=0"

# Write to our file using direct IO, so that this way the write ends up not
# getting compressed, that is, we get a regular extent which is neither
# inlined nor compressed.
# Alternatively, we could have mounted the fs without compression enabled,
# which would result as well in an uncompressed regular extent.
sectorsize=$(_scratch_btrfs_sectorsize)
$XFS_IO_PROG -f -d -c "pwrite -S 0xab 0 $sectorsize" $SCRATCH_MNT/foobar |\
	_filter_xfs_io_numbers

$BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT \
	$SCRATCH_MNT/mysnap1 > /dev/null

# Clone the regular (not inlined) extent.
$XFS_IO_PROG -c \
	"reflink $SCRATCH_MNT/foobar 0 $((2 * $sectorsize)) $sectorsize" \
	$SCRATCH_MNT/foobar | _filter_xfs_io_numbers

$BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT \
	$SCRATCH_MNT/mysnap2 > /dev/null

$BTRFS_UTIL_PROG send -f $send_files_dir/1.snap \
		 $SCRATCH_MNT/mysnap1 2>&1 >/dev/null | _filter_scratch

# Now do an incremental send of the second snapshot. The send stream can have
# a clone operation to clone the extent at offset 0 to offset (2 x sectorsize).
# This operation would fail on the receiver if it has compression enabled, since
# the write operation of the extent at offset 0 was compressed because it was a
# buffered write operation, and btrfs' clone implementation does not allow
# cloning inline extents to offsets different from 0.
$BTRFS_UTIL_PROG send -p $SCRATCH_MNT/mysnap1 -f $send_files_dir/2.snap \
		 $SCRATCH_MNT/mysnap2 2>&1 >/dev/null | _filter_scratch

sum_src_snap1=$(md5sum $SCRATCH_MNT/mysnap1/foobar | awk '{print $1}')
sum_src_snap2=$(md5sum $SCRATCH_MNT/mysnap2/foobar | awk '{print $1}')
echo "File digests in the original filesystem:" >> $seqres.full
echo "md5sum $SCRATCH_MNT/mysnap1/foobar " $sum_src_snap1 >> $seqres.full
echo "md5sum $SCRATCH_MNT/mysnap2/foobar " $sum_src_snap2 >> $seqres.full

# Now recreate the filesystem by receiving both send streams and verify we get
# the same file content that the original filesystem had.
_scratch_unmount
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount "-o compress"

$BTRFS_UTIL_PROG receive -f $send_files_dir/1.snap $SCRATCH_MNT > /dev/null
$BTRFS_UTIL_PROG receive -f $send_files_dir/2.snap $SCRATCH_MNT > /dev/null

sum_dest_snap1=$(md5sum $SCRATCH_MNT/mysnap1/foobar | awk '{print $1}')
sum_dest_snap2=$(md5sum $SCRATCH_MNT/mysnap2/foobar | awk '{print $1}')
echo "File digests in the new filesystem:" | tee -a $seqres.full
echo "md5sum $SCRATCH_MNT/mysnap1/foobar " $sum_src_snap1 >> $seqres.full
echo "md5sum $SCRATCH_MNT/mysnap2/foobar " $sum_src_snap2 >> $seqres.full

[[ $sum_src_snap1 == $sum_dest_snap1 ]] && echo "src and dest 'mysnap1' checksum matched"
[[ $sum_src_snap2 == $sum_dest_snap2 ]] && echo "src and dest 'mysnap2' checksum matched"

status=0
exit