tests/btrfs/191

#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2019 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test No. btrfs/191
#
# Test that an incremental send operation works after deduplicating into the
# same file in both the parent and send snapshots.
#
. ./common/preamble
_begin_fstest auto quick send dedupe

# Override the default cleanup function.
_cleanup()
{
	cd /
	rm -fr $send_files_dir
	rm -f $tmp.*
}

. ./common/filter
. ./common/reflink

_require_test
_require_scratch_dedupe
_require_fssum

send_files_dir=$TEST_DIR/btrfs-test-$seq

rm -fr $send_files_dir
mkdir $send_files_dir

_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount

# Create our first file. The first half of the file has several 64Kb extents
# while the second half as a single 512Kb extent.
$XFS_IO_PROG -f -s -c "pwrite -S 0xb8 -b 64K 0 512K" $SCRATCH_MNT/foo \
	| _filter_xfs_io
$XFS_IO_PROG -c "pwrite -S 0xb8 512K 512K" $SCRATCH_MNT/foo | _filter_xfs_io

# Create the base snapshot and the parent send stream from it.
_btrfs subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap1

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

# Create our second file, that has exactly the same data as the first file.
$XFS_IO_PROG -f -c "pwrite -S 0xb8 0 1M" $SCRATCH_MNT/bar | _filter_xfs_io

# Create the second snapshot, used for the incremental send, before doing the
# file deduplication.
_btrfs subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap2

# Now before creating the incremental send stream:
#
# 1) Deduplicate into a subrange of file foo in snapshot mysnap1. This will drop
#    several extent items and add a new one, also updating the inode's iversion
#    (sequence field in inode item) by 1, but not any other field of the inode;
#
# 2) Deduplicate into a different subrange of file foo in snapshot mysnap2. This
#    will replace an extent item with a new one, also updating the inode's
#    iversion by 1 but not any other field of the inode.
#
# After these two deduplication operations, the inode items, for file foo, are
# identical in both snapshots, but we have different extent items for this inode
# in both snapshots. We want to check this doesn't cause send to fail with an
# error or produce an incorrect stream.

$XFS_IO_PROG -r -c "dedupe $SCRATCH_MNT/bar 0 0 512K" $SCRATCH_MNT/mysnap1/foo \
	| _filter_xfs_io

$XFS_IO_PROG -r -c "dedupe $SCRATCH_MNT/bar 512K 512K 512K" \
	$SCRATCH_MNT/mysnap2/foo | _filter_xfs_io

# Create the incremental send stream.
$BTRFS_UTIL_PROG send -p $SCRATCH_MNT/mysnap1 -f $send_files_dir/2.snap \
	$SCRATCH_MNT/mysnap2 2>&1 | _filter_scratch

# Create the checksums to verify later that the send streams produce correct
# results.
$FSSUM_PROG -A -f -w $send_files_dir/1.fssum $SCRATCH_MNT/mysnap1
$FSSUM_PROG -A -f -w $send_files_dir/2.fssum \
	-x $SCRATCH_MNT/mysnap2/mysnap1 $SCRATCH_MNT/mysnap2

# Now recreate the filesystem by receiving both send streams and verify we get
# the same content 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
$FSSUM_PROG -r $send_files_dir/1.fssum $SCRATCH_MNT/mysnap1
$FSSUM_PROG -r $send_files_dir/2.fssum $SCRATCH_MNT/mysnap2

status=0
exit