tests/overlay/032

#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2017 CTERA Networks. All Rights Reserved.
#
# FS QA Test 032
#
# Test concurrent copy up of lower hardlinks.
#
# Two tasks make a metadata change concurrently on two hardlinks of a large
# lower inode.  The copy up should be triggers by one of the tasks and the
# other should be waiting for copy up to complete.  Both copy up targets
# should end up being upper hardlinks and both metadata changes should be
# applied.
#
. ./common/preamble
_begin_fstest auto quick copyup hardlink

# Import common functions.
. ./common/filter

# real QA test starts here
_supported_fs overlay
_require_scratch
_require_scratch_feature index

# Remove all files from previous tests
_scratch_mkfs

# overlay copy_up doesn't deal with sparse file well, holes will be filled by
# zeros, so if both hardlinks are broken on copy up, we need (2*1G) free space
# on $OVL_BASE_SCRATCH_MNT.
_require_fs_space $OVL_BASE_SCRATCH_MNT $((1024*1024*2))

# Create a large file in lower with 2 hardlinks.
# Make the file have non zero blocks, so copy up won't be able to do
# a naive sparse file copy up optimization.
lowerdir=$OVL_BASE_SCRATCH_MNT/$OVL_LOWER
mkdir -p $lowerdir
$XFS_IO_PROG -fc "pwrite 1g 4k" $lowerdir/zero >> $seqres.full
ln $lowerdir/zero $lowerdir/one
ln $lowerdir/zero $lowerdir/two

# Enable overlay index feature to prevent breaking hardlinks on copy up
_scratch_mount -o index=on

do_cmd()
{
	echo "`date +%T` $1..." >> $seqres.full
	eval "$1"
	echo "`date +%T` ...$1" >> $seqres.full
}

# Perform one modification on each hardlink (size and owner)
do_cmd "echo >> $SCRATCH_MNT/one" &
#
# When hardlinks are broken and overlayfs supports concurrent copy up,
# $seqres.full will show that file two copy up started ~2s after file one
# copy up started and ended ~2s after file one copy up ended.
# With synchronized copy up of lower inodes, $seqres.full will show that
# file two copy up ended at the same time as file one copy up.
# Without sparse file copy up optimizations, copy of 1g on a standard disk
# is expected to take more than 2s.
# If underlying filesystem supports clone, overlay clone up with take less
# than 1s and this test will not be doing concurrent copy up of hardlinks,
# but rather consequent copy up of hardlinks.
#
sleep 2
do_cmd "chown 100 $SCRATCH_MNT/two" &

wait

# Expect all hardlinks to show both metadata modifications (owner and size).
# List <nlink> <owner> <size> <name>:
for f in zero one two; do
	_ls_l -n $SCRATCH_MNT/$f | awk '{ print $2, $3, $5, $9 }' | _filter_scratch
done

status=0
exit