#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2017, Oracle and/or its affiliates.  All Rights Reserved.
#
# FS QA Test No. 421
#
# Test SEEK_HOLE/SEEK_DATA into a region that is marked CoW'd for
# speculative preallocation in the CoW fork and isn't backed by
# data fork extents.
#
# - Set a huge cowextsize hint.
# - Create a file "DD      " (two data blocks, six hole blocks)
# - Reflink copy this file to a second file.
# - dio write to the first block of the second file to create a single
#   large CoW reservation covering the whole file.
# - dio write to block 3, which should be a hole in the data fork.
# - Display the SEEK_HOLE/SEEK_DATA info for the second file to confirm
#   that we see the data in blocks 0-1, the hole at block 2, the data
#   at block 3, and the hole for the rest of the file.
#
# Basically we want to create a file with the following data/CoW forks:
#
# data: DD------
#  cow: dddddddd
#       ^--^---------- these blocks are dirty
#
# And then check that SEEK_HOLE and SEEK_DATA actually find that second
# dirty block even though we've never had a data fork extent mapping the
# second dirty block.  We need the huge cowextsize so that the hole
# area receives preallocation in the CoW fork.
#
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_fs xfs
_require_scratch_reflink
_require_cp_reflink
_require_xfs_io_command "cowextsize"
_require_xfs_io_command "fpunch"

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=8
filesize=$((blksz * nr))

echo "Create the original files"
$XFS_IO_PROG -c "cowextsize" $testdir >> $seqres.full
$XFS_IO_PROG -c "cowextsize $filesize" $testdir >> $seqres.full
$XFS_IO_PROG -c "cowextsize" $testdir >> $seqres.full
$XFS_IO_PROG -f -c "pwrite -S 0x61 0 $((blksz * 2))" -c "truncate $filesize" -c "fpunch $((blksz * 2)) $((blksz * (nr - 2) ))" $testdir/file1 >> $seqres.full
_cp_reflink $testdir/file1 $testdir/file2 >> $seqres.full
$XFS_IO_PROG -f -c "pwrite -S 0 0 $filesize" -c "pwrite -S 0x61 0 $((blksz * 2))" $testdir/file3 >> $seqres.full
_scratch_cycle_mount

echo "Compare files"
md5sum $testdir/file1 | _filter_scratch
md5sum $testdir/file2 | _filter_scratch
md5sum $testdir/file3 | _filter_scratch
# drop caches to make sure the page cache for the unwritten extents is clean
echo 1 > /proc/sys/vm/drop_caches

echo "CoW the shared part then write into the empty part" | tee -a $seqres.full
$XFS_IO_PROG -c "cowextsize" $testdir/file1 >> $seqres.full
$XFS_IO_PROG -c "cowextsize" $testdir/file2 >> $seqres.full
$XFS_IO_PROG -d -c "pwrite -S 0x63 0 $blksz" $testdir/file2 >> $seqres.full
$XFS_IO_PROG -d -c "pwrite -S 0x63 $((blksz * 3)) $blksz" $testdir/file2 >> $seqres.full

$XFS_IO_PROG -d -c "pwrite -S 0x63 0 $blksz" $testdir/file3 >> $seqres.full
$XFS_IO_PROG -d -c "pwrite -S 0x63 $((blksz * 3)) $blksz" $testdir/file3 >> $seqres.full

$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file1 >> $seqres.full 2>&1
$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file2 >> $seqres.full 2>&1
$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file3 >> $seqres.full 2>&1

echo "Seek holes and data in file1"
$XFS_IO_PROG -c "seek -a -r 0" $testdir/file1
echo "Seek holes and data in file2"
$XFS_IO_PROG -c "seek -a -r 0" $testdir/file2

echo "Compare files"
md5sum $testdir/file1 | _filter_scratch
md5sum $testdir/file2 | _filter_scratch
md5sum $testdir/file3 | _filter_scratch
# drop caches to make sure the page cache for the unwritten extents is clean
echo 1 > /proc/sys/vm/drop_caches

echo "sync filesystem" | tee -a $seqres.full
sync

$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file1 >> $seqres.full 2>&1
$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file2 >> $seqres.full 2>&1
$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file3 >> $seqres.full 2>&1

echo "Seek holes and data in file1"
$XFS_IO_PROG -c "seek -a -r 0" $testdir/file1
echo "Seek holes and data in file2"
$XFS_IO_PROG -c "seek -a -r 0" $testdir/file2

echo "Compare files"
md5sum $testdir/file1 | _filter_scratch
md5sum $testdir/file2 | _filter_scratch
md5sum $testdir/file3 | _filter_scratch
# drop caches to make sure the page cache for the unwritten extents is clean
echo 1 > /proc/sys/vm/drop_caches

echo "Remount" | tee -a $seqres.full
_scratch_cycle_mount

$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file1 >> $seqres.full 2>&1
$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file2 >> $seqres.full 2>&1
$XFS_IO_PROG -c "bmap -ev" -c "bmap -cv" $testdir/file3 >> $seqres.full 2>&1

echo "Seek holes and data in file1"
$XFS_IO_PROG -c "seek -a -r 0" $testdir/file1
echo "Seek holes and data in file2"
$XFS_IO_PROG -c "seek -a -r 0" $testdir/file2

echo "Compare files"
md5sum $testdir/file1 | _filter_scratch
md5sum $testdir/file2 | _filter_scratch
md5sum $testdir/file3 | _filter_scratch

# success, all done
status=0
exit