#! /bin/bash
# FS QA Test No. 227
#
# xfs_fsr QA tests
# run xfs_fsr over the test filesystem to give it a wide and varied set of
# inodes to try to defragment. This is effectively a crash/assert failure
# test looking for corruption induced by the kernel inadequately checking
# the indoes to be swapped. It also is good for validating fsr's attribute fork
# generation code.
#
#-----------------------------------------------------------------------
# Copyright (c) 2010 Dave Chinner.  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
#
#-----------------------------------------------------------------------
#
# creator
owner=david@fromorbit.com

seq=`basename $0`
echo "QA output created by $seq"

here=`pwd`
tmp=/tmp/$$
status=1	# failure is the default!

_cleanup()
{
    rm -f $tmp.*
}

trap "_cleanup ; exit \$status" 0 1 2 3 15

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

# real QA test starts here
_supported_fs xfs
_supported_os Linux
_require_scratch

[ "$XFS_FSR_PROG" = "" ] && _notrun "xfs_fsr not found"

# create freespace holes of 1-3 blocks in length
#
# This is done to ensure that defragmented files have roughly 1/3 the
# number of extents they started with. This will ensure we get
# transistions from btree format (say 15 extents) to extent format
# (say 5 extents) and lots of variations around that dependent on the
# number of attributes in the files being defragmented.
#
fragment_freespace()
{
	_file="$SCRATCH_MNT/not_free"

	for i in `seq 0 1 10000`; do
		echo foo > $_file.$i
	done
	sync

	for i in `seq 0 2 10000`; do
		rm -f $_file.$i
	done
	for i in `seq 0 7 10000`; do
		rm -f $_file.$i
	done
	sync

	# and now use up all the remaining extents larger than 3 blocks
	dd if=/dev/zero of=$_file.large bs=4k count=1024 > /dev/null 2>&1
	sync
}

create_attrs()
{
	for foo in `seq 0 1 $1`; do
		$SETFATTR_PROG -n user.$foo -v 0xbabe $2
	done
}

create_data()
{
	for foo in `seq $1 -1 0`; do
		let offset=$foo*4096
		$XFS_IO_PROG -f -c "pwrite $offset 4096" -c "fsync" $2 > /dev/null 2>&1
	done
	xfs_bmap -vp $2
}

# create the designated file with a certain number of attributes and a certain
# number of data extents. Reverse order synchronous data writes are used to
# create fragmented files, though with the way the filesystem freespace is
# fragmented, this is probably not necessary. Create the attributes first so
# that they cause the initial fork offset pressure to move it about.
#
create_target_attr_first()
{
	nattrs=$1
	file_blocks=$2
	target=$3

	rm -f $target
	echo > $target
	create_attrs $nattrs $target
	create_data $file_blocks $target
}

# Same as create_target_attr_first, but this time put the attributes on after
# the data extents have been created. This puts different pressure on the
# inode fork offset, so should exercise the kernel code differently and give us
# a different pattern of fork offsets to work with compared to creating the
# attrs first.
#
create_target_attr_last()
{
	nattrs=$1
	file_blocks=$2
	target=$3

	rm -f $target
	echo > $target
	create_data $file_blocks $target
	create_attrs $nattrs $target
}

rm -f $seq.full

# use a small filesystem so we can control freespace easily
_scratch_mkfs_sized $((50 * 1024 * 1024)) >> $seq.full 2>&1
_scratch_mount
fragment_freespace

# unmount and remount to reset all allocator indexes
umount $SCRATCH_MNT
_scratch_mount

# create a range of source files, then fsr them to a known size
#
# This assumes 256 byte inodes.
#
# n = number of target fragments for xfs_fsr
#	- only a guideline, but forces multiple fragments via sync writes
#	- start at 4 as that typically covers all extent format situations
#	- end at 12 as that is beyond the maximum that canbe fit in extent
#	  format
# i = number of 2 byte attributes on the file
#	- it takes 6 attributes to change the fork offset from the start value
#	  of 120 bytes to 112 bytes, so we start at 5.
#	- 15 is enough to push to btree format, so we stop there.
# j = number of data extents on the file
#	- start in extent format, but we also want btree format as well, so
#	  start at 5 so that the number of attributes determines the starting
#	  format.
#	- need enough extents that if they are all 3 blocks in length the final
#	  format will be dependent on the number of attributes on the inode. 20
#	  initial single block extents gives us 6-8 extents after defrag which
#	  puts us right on the threshold of what the extent format can hold.

targ=$SCRATCH_MNT/fsr_test_file.$$
for n in `seq 4 1 12`; do
	echo "*** n == $n ***" >> $seq.full
	for i in `seq 5 1 15`; do
		for j in `seq 5 1 20`; do
			create_target_attr_first $i $j $targ.$i.$j >> $seq.full 2>&1
		done
		FSRXFSTEST=true xfs_fsr -d -v -C $n $targ.$i.* >> $seq.full 2>&1
		xfs_bmap -vp $targ.$i.* >> $seq.full 2>&1
		for j in `seq 5 1 20`; do
			create_target_attr_last $i $j $targ.$i.$j >> $seq.full 2>&1
		done
		FSRXFSTEST=true xfs_fsr -d -v -C $n $targ.$i.* >> $seq.full 2>&1
		xfs_bmap -vp $targ.$i.* >> $seq.full 2>&1
	done
done

umount $SCRATCH_MNT
echo "--- silence is golden ---"
status=0 ; exit
