#! /bin/bash
# FS QA Test No. 205
#
# Test out ENOSPC flushing on small filesystems.
#
#-----------------------------------------------------------------------
# Copyright (c) 2009 Dave Chinner
#
# 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"

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

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

# real QA test starts here
_supported_fs xfs
_supported_os Linux

# single AG will cause xfs_repair to fail checks.
_require_scratch_nocheck

rm -f $seqres.full

_scratch_mkfs_xfs -d size=16m -b size=512 -l size=4944b >> $seqres.full 2>&1
_scratch_mount

# fix the reserve block pool to a known size so that the enospc calculations
# work out correctly.
_scratch_resvblks 1024 >> $seqres.full 2>&1

# on a 16MB filesystem, there's 32768x512byte blocks. used is:
#	- 4944 in the log,
#	- 32+1 for the root inode cluster
#	- 4 for the AG header
#	- 2 for free space btrees
#	- 4 for the AGFL
#	- min(%5, 1024) = 1024 blocks for the reserve pool
#	- about 15 blocks I can't account for right now.
# That leaves ~26,745 blocks free to use.
#
# Writing the following three files fill the fs almost exactly.
#
# $ df -k /mnt/scratch
# Filesystem           1K-blocks      Used Available Use% Mounted on
# /dev/ubdc                13912     13908         4 100% /mnt/scratch
#
dd if=/dev/zero of=$SCRATCH_MNT/fred bs=512 count=25000 2>&1 | _filter_dd
dd if=/dev/zero of=$SCRATCH_MNT/fred2 bs=512 count=500 2>&1 | _filter_dd
dd if=/dev/zero of=$SCRATCH_MNT/fred3 bs=512 count=245 2>&1 | _filter_dd
rm -f $SCRATCH_MNT/fred*

echo "*** one file"
# now try a single file of that size
dd if=/dev/zero of=$SCRATCH_MNT/fred bs=512 count=26745 2>&1 | _filter_dd
#rm -f $SCRATCH_MNT/fred*

echo "*** one file, a few bytes at a time"
# now try a single file of that size
dd if=/dev/zero of=$SCRATCH_MNT/fred bs=15 count=$[26745/15*512] 2>&1 | _filter_dd

# success, all done
echo "*** done"
status=0
