apfstests/tests/btrfs/055

#! /bin/bash
# FS QA Test No. btrfs/055
#
# Regression test for the btrfs ioctl clone operation when the source range
# contains hole(s) and the FS has the NO_HOLES feature enabled (file holes
# don't need file extent items in the btree to represent them).
#
# This issue is fixed by the following linux kernel btrfs patch:
#
#    Btrfs: fix clone to deal with holes when NO_HOLES feature is enabled
#
#-----------------------------------------------------------------------
# Copyright (c) 2014 Filipe Manana.  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"

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

_cleanup()
{
    rm -fr $tmp
}

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

# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_cloner
_require_btrfs_fs_feature "no_holes"
_require_btrfs_mkfs_feature "no-holes"
_need_to_be_root

rm -f $seqres.full

test_btrfs_clone_with_holes()
{
	_scratch_mkfs "$1" >/dev/null 2>&1
	_scratch_mount

	# Create a file with 4 extents and 1 hole, all with a size of 8Kb each.
	# The hole is in the range [16384, 24576[.
	$XFS_IO_PROG -s -f -c "pwrite -S 0x01 -b 8192 0 8192" \
			-c "pwrite -S 0x02 -b 8192 8192 8192" \
			-c "pwrite -S 0x04 -b 8192 24576 8192" \
			-c "pwrite -S 0x05 -b 8192 32768 8192" \
		$SCRATCH_MNT/foo | _filter_xfs_io

	# Clone destination file, 1 extent of 96kb.
	$XFS_IO_PROG -s -f -c "pwrite -S 0xff -b 98304 0 98304" \
		$SCRATCH_MNT/bar | _filter_xfs_io

	# Clone 2nd extent, 8Kb hole and 3rd extent of foo into bar.
	$CLONER_PROG -s 8192 -d 0 -l 24576 $SCRATCH_MNT/foo $SCRATCH_MNT/bar

	# Verify both extents and the hole were cloned.
	echo "1) Check both extents and the hole were cloned"
	od -t x1 $SCRATCH_MNT/bar

	# Cloning range starts at the middle of an hole.
	$CLONER_PROG -s 20480 -d 32768 -l 12288 $SCRATCH_MNT/foo \
		$SCRATCH_MNT/bar

	# Verify that half of the hole and the following 8Kb extent were cloned.
	echo "2) Check half hole and one 8Kb extent were cloned"
	od -t x1 $SCRATCH_MNT/bar

	# Cloning range ends at the middle of an hole.
	$CLONER_PROG -s 0 -d 65536 -l 20480 $SCRATCH_MNT/foo $SCRATCH_MNT/bar

	# Verify that 2 extents of 8kb and a 4kb hole were cloned.
	echo "3) Check that 2 extents of 8kb eacg and a 4kb hole were cloned"
	od -t x1 $SCRATCH_MNT/bar

	# Create a 24Kb hole at the end of the source file (foo).
	$XFS_IO_PROG -c "truncate 65536" $SCRATCH_MNT/foo
	sync

	# Now clone a range that overlaps that hole at the end of the foo file.
	# It should clone the last 4Kb of the extent at offset 32768 and the
	# first 8kb of the 24kb hole at the end of foo.
	$CLONER_PROG -s 36864 -d 86016 -l 12288 $SCRATCH_MNT/foo \
		$SCRATCH_MNT/bar

	# Verify that the second half of the 8Kb extent at offset 32768 of foo
	# and the first 8Kb of the 24kb hole of foo were cloned into bar.
	echo "4) Check that 4kb of 1 extent and 8Kb of an hole were cloned"
	od -t x1 $SCRATCH_MNT/bar

	# Clone the same range as before, but clone it into a different offset
	# of the target (bar) such that it increases the size of the target
	# by 8Kb.
	$CLONER_PROG -s 36864 -d 94208 -l 12288 $SCRATCH_MNT/foo \
		$SCRATCH_MNT/bar

	# Verify that the second half of the 8Kb extent at offset 32768 of foo
	# and the first 8Kb of the 24kb hole of foo were cloned into bar at
	# bar's offset 94208 and that bar's size increased by 8Kb.
	echo "5) Check that 4kb of 1 extent and 8Kb of an hole were cloned and file size increased"
	od -t x1 $SCRATCH_MNT/bar

	# Create a new completely sparse file (no extents, it's a big hole).
	$XFS_IO_PROG -f -c "truncate 100000" $SCRATCH_MNT/qwerty
	sync

	# Test cloning a range from the sparse file to the bar file without
	# increasing bar's size.
	$CLONER_PROG -s 4096 -d 0 -l 8192 $SCRATCH_MNT/qwerty $SCRATCH_MNT/bar

	# First 8Kb of bar should now be zeroes.
	echo "6) Check that 8kb of the hole were cloned"
	od -t x1 $SCRATCH_MNT/bar

	# Test cloning a range from the sparse file to the end of the bar file.
	# The bar file currently has a size of 106496 bytes.
	$CLONER_PROG -s 0 -d 106496 -l 32768 $SCRATCH_MNT/qwerty \
		$SCRATCH_MNT/bar

	# Verify bar's size increased to 106496 + 32768 bytes (136Kb), and its
	# last 32768 bytes are all zeroes.
	echo "7) Check that 32kb of the hole were cloned and the file size increased"
	od -t x1 $SCRATCH_MNT/bar

	# Verify that there are no consistency errors.
	_check_scratch_fs
}

# Regardless of the NO_HOLES feature being enabled or not, the test results
# should be exactly the same for both cases.

echo "Testing without the NO_HOLES feature"
# As of btrfs-progs 3.14.x, the no-holes feature isn't enabled by default.
# But explicitly disable it at mkfs time as it might be enabled by default
# in future versions.
test_btrfs_clone_with_holes "-O ^no-holes"

_scratch_unmount

echo "Testing with the NO_HOLES feature enabled"
test_btrfs_clone_with_holes "-O no-holes"

status=0
exit