reflink: test intersecting CoW and falloc/fpunch/fzero/fcollapse/finsert/ftrunc

Ensure that we correctly handle a CoW operation immediately followed
by a truncate, falloc, fpunch, fzero, fcollapse, and finsert operation
in the middle of the CoW'd region before any flush can occur.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

tests/generic/262

@@ -0,0 +1,93 @@
+#! /bin/bash
+# FS QA Test No. 262
+#
+# finsert a file at midway through a CoW region.
+#
+# This test is dependent on the system page size, so we cannot use md5 in
+# the golden output; we can only compare to a check file.
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2016, Oracle and/or its affiliates.  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!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+    cd /
+    rm -rf $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/reflink
+
+# real QA test starts here
+_supported_os Linux
+_require_scratch_reflink
+_require_cp_reflink
+_require_xfs_io_command "finsert"
+
+rm -f $seqres.full
+
+
+echo "Format and mount"
+_scratch_mkfs > $seqres.full 2>&1
+_scratch_mount >> $seqres.full 2>&1
+
+testdir=$SCRATCH_MNT/test-$seq
+mkdir $testdir
+
+blksz=65536
+nr=4
+filesize=$((blksz * nr))
+
+echo "Create the original files"
+_pwrite_byte 0x61 0 $filesize $testdir/file1 >> $seqres.full
+_cp_reflink $testdir/file1 $testdir/file2 >> $seqres.full
+_pwrite_byte 0x61 0 $filesize $testdir/file2.chk >> $seqres.full
+_scratch_remount
+
+echo "Compare files"
+md5sum $testdir/file1 | _filter_scratch
+md5sum $testdir/file2 | _filter_scratch
+md5sum $testdir/file2.chk | _filter_scratch
+
+echo "CoW and unmount"
+$XFS_IO_PROG -f -c "pwrite -S 0x62 -b $((blksz * 2)) $blksz $((blksz * 2))" -c "finsert $((blksz * 2)) $blksz" $testdir/file2 >> $seqres.full
+_scratch_remount
+_pwrite_byte 0x62 $blksz $blksz $testdir/file2.chk >> $seqres.full
+_pwrite_byte 0x00 $((blksz * 2)) $blksz $testdir/file2.chk >> $seqres.full
+_pwrite_byte 0x62 $((blksz * 3)) $blksz $testdir/file2.chk >> $seqres.full
+_pwrite_byte 0x61 $((blksz * 4)) $blksz $testdir/file2.chk >> $seqres.full
+_scratch_remount
+
+echo "Compare files"
+md5sum $testdir/file1 | _filter_scratch
+md5sum $testdir/file2 | _filter_scratch
+md5sum $testdir/file2.chk | _filter_scratch
+
+# success, all done
+status=0
+exit