#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2018 CTERA Networks. All Rights Reserved.
#
# FS QA Test No. 055
#
# Test overlay file handle of dir with ancestor under lower redirect
#
# Overlayfs with nfs_export enabled, indexes all directories on copy up.
# Directory index is requires for decoding lower directory file handles
# in case ancestors have been renamed.
#
# When enabling nfs_export on an overlay that has merge dirs with lower
# layer redirects, the possibility of ancestor rename requires special
# handling when encoding lower directory file handles from layer > 1.
#
# - Check decode of lower dir with parent under lower redirect
# - Check decode of lower dir with grandparent under lower redirect
# - Check decode of lower dir after rename of lower redirected parent
# - Check decode of lower dir after rename of lower redirected grandparent
#
# This test requires and enables overlayfs NFS export support and merge
# dir rename support (redirect_dir).
# NFS export support depends on and requires overlayfs index feature.
#
# Regression test for kernel commit 2ca3c148a062 ("ovl: check lower ancestry
# on encode of lower dir file handle")
#
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 -f $tmp.*
	# Cleanup overlay scratch mount that is holding base test mount
	# to prevent _check_test_fs and _test_umount from failing before
	# _check_scratch_fs _scratch_umount
	$UMOUNT_PROG $SCRATCH_MNT 2>/dev/null
}

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

# real QA test starts here

_supported_fs overlay
_require_test
_require_test_program "open_by_handle"
# Use non-default scratch underlying overlay dirs, we need to check
# them explicity after test.
_require_scratch_nocheck
# We need to require all features together, because nfs_export cannot
# be enabled when index is disabled
_require_scratch_overlay_features index nfs_export redirect_dir

# Lower is on test partition
lower=$OVL_BASE_TEST_DIR/$OVL_LOWER-$seq
# Upper/work are on scratch partition
middle=$OVL_BASE_SCRATCH_MNT/$OVL_LOWER
upper=$OVL_BASE_SCRATCH_MNT/$OVL_UPPER
work=$OVL_BASE_SCRATCH_MNT/$OVL_WORK

NUMFILES=1

# Create test dir and empty test files
create_test_files()
{
	local dir=$1
	local opt=$2

	mkdir -p $dir
	$here/src/open_by_handle -cp $opt $dir $NUMFILES
}

# Test encode/decode file handles on overlay mount
test_file_handles()
{
	local dir=$1
	shift

	echo test_file_handles $dir $* | _filter_scratch | \
				sed -e "s,$tmp\.,,g"
	$here/src/open_by_handle $* $dir $NUMFILES
}

# Re-create lower/middle/upper/work dirs
create_dirs()
{
	# Create lower dir on test partition
	rm -rf $lower
	mkdir $lower

	# Create middle/upper/work dirs on scratch partition
	_scratch_mkfs
}

# Mount an overlay on $SCRATCH_MNT with lower layer on test partition
# and middle and upper layer on scratch partition
mount_dirs()
{
	_overlay_scratch_mount_dirs $middle:$lower $upper $work \
				-o "index=on,nfs_export=on,redirect_dir=on"
}

# Unmount the overlay without unmounting base fs and check the
# underlying dirs
unmount_dirs()
{
	$UMOUNT_PROG $SCRATCH_MNT

	_overlay_check_scratch_dirs $middle:$lower $upper $work \
				-o "index=on,nfs_export=on,redirect_dir=on"
}

# Check file handles of dir with ancestor under lower redirect
create_dirs
create_test_files $lower/origin -w
create_test_files $lower/origin/dir -w
create_test_files $lower/origin/dir/subdir -w
create_test_files $lower/origin/parent/child -w
# Create lower redirected merge dir
mkdir $middle/merged
setfattr -n "trusted.overlay.redirect" -v "origin" $middle/merged
mount_dirs
# Check encode/decode/read of lower dir with parent under lower redirect
# This is expected to copy up merged/dir and encode an upper file handle
test_file_handles $SCRATCH_MNT/merged/dir -p -o $tmp.dir_file_handles
test -d $upper/merged/dir || echo "merged/dir not copied up"
# Check encode/decode/read of lower dir with grandparent under lower redirect
# This is expected to encode a lower file handle
test_file_handles $SCRATCH_MNT/merged/dir/subdir -p -o $tmp.subdir_file_handles
test -d $upper/merged/dir/subdir && echo "merged/dir/subdir unexpected copy up"
# This is expected to copy up parent and encode a lower file handle
test_file_handles $SCRATCH_MNT/merged/parent/child -p -o $tmp.child_file_handles
test -d $upper/merged/parent || echo "merged/parent not copied up"
test -d $upper/merged/parent/child && echo "merged/parent/child unexpected copy up"

# Rename lower redirected merge dir
mv $SCRATCH_MNT/merged $SCRATCH_MNT/merged.new/
# Check open, read and readdir from stored file handles
# (testdir argument is the mount point and NOT the dir
#  we are trying to open by stored file handle)
test_file_handles $SCRATCH_MNT -rp -i $tmp.dir_file_handles
test_file_handles $SCRATCH_MNT -rp -i $tmp.subdir_file_handles
test_file_handles $SCRATCH_MNT -rp -i $tmp.child_file_handles
# Retry decoding lower subdir file handles when indexed ancestor is in dcache
# (providing the ancestor dir argument pins the ancestor to dcache)
test_file_handles $SCRATCH_MNT/merged.new/dir -rp -i $tmp.dir_file_handles
test_file_handles $SCRATCH_MNT/merged.new/dir -rp -i $tmp.subdir_file_handles
test_file_handles $SCRATCH_MNT/merged.new/parent -rp -i $tmp.child_file_handles
unmount_dirs

status=0
exit