xfstests: test speculative preallocation reclaim on ENOSPC/EDQUOT

new file mode 100755
index 0000000..1e092a9
@@ -0,0 +1,200 @@
+#!/bin/bash
+# FS QA Test No. xfs/014
+#
+# Test the behavior of XFS dynamic speculative preallocation at ENOSPC and
+# EDQUOT conditions. Speculative preallocation allocates post-EOF space to files
+# as they are extended. This test creates conditions where an fs is near a space
+# limit with lingering, relatively significant preallocations and verifies that
+# new writers reclaim said preallocations rather than prematurely fail with
+# ENOSPC/EDQUOT.
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2014 Red Hat, Inc.  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"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/quota
+
+_cleanup()
+{
+	cd /
+	umount $LOOP_MNT 2>/dev/null
+	umount $SCRATCH_MNT 2>/dev/null
+	rm -f $tmp.*
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# Create a file using a repeated open, extending write and close pattern. This
+# causes the preallocation to persist after the file is closed. Preallocation
+# will not be reclaimed unless the inode is evicted or we hit an allocation
+# failure.
+_spec_prealloc_file()
+{
+	file=$1
+
+	rm -f $file
+
+	# a few file extending open-write-close cycles should be enough to
+	# trigger the fs to retain preallocation. write 256k in 32k intervals to
+	# be sure
+	for i in $(seq 0 32768 262144); do
+		$XFS_IO_PROG -f -c "pwrite $i 32k" $file >> $seqres.full
+	done
+
+	# write a 4k aligned amount of data to keep the calculations simple
+	$XFS_IO_PROG -c "pwrite 0 128m" $file >> $seqres.full
+
+	size=`stat -c "%s" $file`
+	blocks=`stat -c "%b" $file`
+	blocksize=`stat -c "%B" $file`
+
+	prealloc_size=$((blocks * blocksize - size))
+	if [ $prealloc_size -eq 0 ]; then
+		echo "Warning: No speculative preallocation for $file." \
+			"Check use of the allocsize= mount option."
+	fi
+
+	# keep a running total of how much preallocation we've created
+	TOTAL_PREALLOC=$((TOTAL_PREALLOC + prealloc_size))
+}
+
+_consume_free_space()
+{
+	dir=$1
+
+	# allocate all but 10MB of available space
+	freesp=`df -m $dir | awk '/^\// { print $4 - 10 }'`
+	$XFS_IO_PROG -f -c "falloc 0 ${freesp}M" $dir/spc
+}
+
+# Create several files with preallocation and consume the remaining free space
+# via fallocate to the put the fs at ENOSPC. Create a set of background writers
+# to write into ENOSPC and cause the preallocation to be reclaimed and
+# reallocated to the new writers.
+_test_enospc()
+{
+	dir=$1
+
+	rm -rf $dir/*
+
+	TOTAL_PREALLOC=0
+	for i in $(seq 0 3); do
+		_spec_prealloc_file $dir/pre$i
+	done
+
+	_consume_free_space $dir
+
+	# consume 1/2 of the current preallocation across the set of 4 writers
+	write_size=$((TOTAL_PREALLOC / 2 / 4))
+	for i in $(seq 0 3); do
+		$XFS_IO_PROG -f -c "pwrite 0 $write_size" $dir/file.$i \
+			>> $seqres.full &
+	done
+
+	wait
+}
+
+# Create preallocations accounted by both user and group quotas. Set the
+# associated quota hard limits to put them at EDQUOT. Verify that a new writer
+# reclaims the preallocated space and proceeds without error.
+_test_edquot()
+{
+	dir=$1
+
+	rm -rf $dir/*
+
+	TOTAL_PREALLOC=0
+	_spec_prealloc_file $dir/user
+	chown $qa_user $dir/user
+
+	_spec_prealloc_file $dir/group
+	chgrp $qa_group $dir/group
+
+	# writing to a file under both quotas means both will be reclaimed on
+	# allocation failure
+	touch $dir/file
+	chown $qa_user $dir/file
+	chgrp $qa_group $dir/file
+
+	# put both quotas at EDQUOT
+	blks=`$XFS_QUOTA_PROG -xc "quota -u $qa_user" $dir | \
+		tail -n 1 | awk '{ print $2 }'`
+	$XFS_QUOTA_PROG -xc "limit -u bhard=${blks}k $qa_user" $dir
+	blks=`$XFS_QUOTA_PROG -xc "quota -g $qa_grup" $dir | \
+		tail -n 1 | awk '{ print $2 }'`
+	$XFS_QUOTA_PROG -xc "limit -g bhard=${blks}k $qa_group" $dir
+
+	# each quota has a single file worth of preallocation to reclaim. leave
+	# some wiggle room and write to 1/3 the total.
+	write_size=$((TOTAL_PREALLOC / 3))
+	$XFS_IO_PROG -c "pwrite 0 $write_size" $dir/file >> $seqres.full
+}
+
+# real QA test starts here
+_supported_fs xfs
+_supported_os Linux
+
+_require_scratch
+_require_xfs_io_command "falloc"
+_require_loop
+_require_quota
+_require_user
+_require_group
+
+rm -f $seqres.full
+
+echo "Silence is golden."
+
+_scratch_mkfs_xfs >> $seqres.full 2>&1
+_scratch_mount
+
+# make sure the background eofblocks scanner doesn't interfere
+orig_sp_time=`cat /proc/sys/fs/xfs/speculative_prealloc_lifetime`
+echo 9999 > /proc/sys/fs/xfs/speculative_prealloc_lifetime
+
+LOOP_FILE=$SCRATCH_MNT/$seq.fs
+LOOP_MNT=$SCRATCH_MNT/$seq.mnt
+
+$MKFS_XFS_PROG -d "file=1,name=$LOOP_FILE,size=10g" >> $seqres.full 2>&1
+
+mkdir -p $LOOP_MNT
+mount -t xfs -o loop,uquota,gquota $LOOP_FILE $LOOP_MNT || \
+	_fail "Failed to mount loop fs."
+
+_test_enospc $LOOP_MNT
+_test_edquot $LOOP_MNT
+
+umount $LOOP_MNT
+
+echo $orig_sp_time > /proc/sys/fs/xfs/speculative_prealloc_lifetime
+
+umount $SCRATCH_MNT
+_check_scratch_fs
+
+status=0
+exit

new file mode 100644
index 0000000..5d78183
@@ -0,0 +1,2 @@
+QA output created by 014
+Silence is golden.

index 19fd968..13f07b8 100644
@@ -10,6 +10,7 @@
 010 auto quick repair
 012 rw auto quick
 013 auto metadata stress
+014 auto enospc quick quota
 016 rw auto quick
 017 mount auto quick stress
 018 deprecated # log logprint v2log