#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2020 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test No. 203
#
# Test that an incremental send operation works correctly when a file has shared
# extents with itself in the send snapshot, with a hole between them, and the
# file size has increased in the send snapshot.
#
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 -f $tmp.*
	rm -fr $send_files_dir
}

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

# real QA test starts here
_supported_fs btrfs
_require_test
_require_scratch_reflink

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
_scratch_mount

# Create our test file with a size of 64K in the parent snapshot.
# After the parent snapshot is created, we will increase its size and then clone
# one of its extents into a different offset and leave a hole between the shared
# extents. The shared extents will be located at offsets greater then size of the
# file in the parent snapshot.
$XFS_IO_PROG -f -c "pwrite -S 0xf1 0 64K" $SCRATCH_MNT/foobar | _filter_xfs_io

$BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/base 2>&1 \
	| _filter_scratch

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

# Create a 320K extent at file offset 512K, with chunks of 64K having different
# content (to check cloning operations from send refer to the correct ranges).
# After that clone a range that includes a hole and a part of the extent created
# before - the clone range starts at an offset (448K) lower then the extent's
# offset (512K). We want to see the existence of the hole doesn't confuse the
# kernel's send code to send an invalid clone operation (with a source range
# going beyond the file's current size). The hole that confused send to issue
# an invalid clone operation spans the file range from offset 384K to 512K.
#
# Use offsets and ranges that are aligned to 64K, so that the test can run on
# machines with any page size (and therefore block size).
#
$XFS_IO_PROG -c "pwrite -S 0xab 512K 64K" \
	     -c "pwrite -S 0xcd 576K 64K" \
	     -c "pwrite -S 0xef 640K 64K" \
	     -c "pwrite -S 0x64 704K 64K" \
	     -c "pwrite -S 0x73 768K 64K" \
	     -c "reflink $SCRATCH_MNT/foobar 448K 192K 192K" \
	     $SCRATCH_MNT/foobar | _filter_xfs_io

$BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/incr 2>&1 \
	| _filter_scratch

$BTRFS_UTIL_PROG send -p $SCRATCH_MNT/base -f $send_files_dir/2.snap \
		 $SCRATCH_MNT/incr 2>&1 | _filter_scratch

echo "File foobar digest in the original filesystem:"
_md5_checksum $SCRATCH_MNT/incr/foobar

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

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

echo "File foobar digest in the new filesystem:"
_md5_checksum $SCRATCH_MNT/incr/foobar

status=0
exit