#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2019 CTERA Networks. All Rights Reserved.
#
# FS QA Test No. 068
#
# Test encode/decode of nested overlay file handles
#
# This is a variant of overlay file handles test for an overlayfs that is
# nested over another lower overlayfs on the same fs.
#
# - Check encode/write/decode/read content of lower/upper file handles
# - Check encode/decode/write/read content of lower/upper file handles
# - Check decode/read of unlinked lower/upper files and directories
# - Check decode/read of lower file handles after copy up, link and unlink
# - Check decode/read of lower file handles after rename of parent and self
#
# This test does not cover connectable file handles of non-directories,
# because name_to_handle_at() syscall does not support requesting connectable
# file handles.
#
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.*
	# Unmount the nested overlay mount
	$UMOUNT_PROG $mnt2 2>/dev/null
}

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

# real QA test starts here

_supported_fs overlay
_supported_os Linux
_require_scratch
# _require_exportfs already requires open_by_handle, but let's not count on it
_require_test_program "open_by_handle"
# 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 dir of nested overlay is the scratch overlay mount at SCRATCH_MNT
upper2=$OVL_BASE_SCRATCH_MNT/$OVL_UPPER.2
work2=$OVL_BASE_SCRATCH_MNT/$OVL_WORK.2
mnt2=$OVL_BASE_SCRATCH_MNT/$OVL_MNT.2

lowerdir=$OVL_BASE_SCRATCH_MNT/$OVL_LOWER/lowertestdir
upperdir=$OVL_BASE_SCRATCH_MNT/$OVL_UPPER/uppertestdir
lowertestdir=$mnt2/lowertestdir
uppertestdir=$mnt2/uppertestdir
NUMFILES=1

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

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

# Re-create lower/upper/work dirs
create_dirs()
{
	# Create the underlying overlay dirs
	_scratch_mkfs

	# Create the nested overlay upper dirs
	mkdir -p $upper2 $work2 $mnt2
}

# Mount a nested overlay with $SCRATCH_MNT as lower layer
mount_dirs()
{
	# Mount the underlying overlay
	_scratch_mount -o "index=on,nfs_export=on,redirect_dir=on"

	# Mount the nested overlay
	_overlay_mount_dirs $SCRATCH_MNT $upper2 $work2 overlay2 $mnt2 \
		-o "index=on,nfs_export=on,redirect_dir=on" 2>/dev/null ||
		_notrun "cannot mount nested overlay with nfs_export=on option"
	_check_overlay_feature nfs_export overlay2 $mnt2
}

# Unmount the nested overlay mount and check underlying overlay layers
unmount_dirs()
{
	# unmount & check nested overlay
	$UMOUNT_PROG $mnt2
	_overlay_check_dirs $SCRATCH_MNT $upper2 $work2 \
		-o "index=on,nfs_export=on,redirect_dir=on"

	# unmount & check underlying overlay
	_scratch_unmount
	_check_scratch_fs
}

# Check non-stale file handles of lower/upper files and verify
# that handle decoded before copy up is encoded to upper after
# copy up. Verify reading data from file open by file handle
# and verify access_at() with dirfd open by file handle.
create_dirs
create_test_files $upperdir
create_test_files $lowerdir
mount_dirs
# Check encode/decode of upper regular file handles
test_file_handles $uppertestdir
# Check encode/decode of upper dir file handle
test_file_handles $uppertestdir -p
# Check encode/write/decode/read/write of upper file handles
test_file_handles $uppertestdir -wrap
# Check encode/decode of lower regular file handles before copy up
test_file_handles $lowertestdir
# Check encode/decode of lower dir file handles before copy up
test_file_handles $lowertestdir -p
# Check encode/write/decode/read/write of lower file handles across copy up
test_file_handles $lowertestdir -wrap
unmount_dirs

# Check copy up after encode/decode of lower/upper files
# (copy up of disconnected dentry to index dir)
create_dirs
create_test_files $upperdir
create_test_files $lowerdir
mount_dirs
# Check encode/decode/write/read of upper regular file handles
test_file_handles $uppertestdir -a
test_file_handles $uppertestdir -r
# Check encode/decode/write/read of lower regular file handles
test_file_handles $lowertestdir -a
test_file_handles $lowertestdir -r
unmount_dirs

# Check non-stale handles to unlinked but open lower/upper files
create_dirs
create_test_files $upperdir
create_test_files $upperdir.rw
create_test_files $lowerdir
create_test_files $lowerdir.rw
mount_dirs
test_file_handles $uppertestdir -dk
# Check encode/write/unlink/decode/read of upper regular file handles
test_file_handles $uppertestdir.rw -rwdk
test_file_handles $lowertestdir -dk
# Check encode/write/unlink/decode/read of lower file handles across copy up
test_file_handles $lowertestdir.rw -rwdk
unmount_dirs

# Check stale handles of unlinked lower/upper files (nlink = 1,0)
create_dirs
create_test_files $upperdir
create_test_files $lowerdir
mount_dirs
# Check decode of upper file handles after unlink/rmdir (nlink == 0)
test_file_handles $uppertestdir -dp
# Check decode of lower file handles after unlink/rmdir (nlink == 0)
test_file_handles $lowertestdir -dp
unmount_dirs

# Check non-stale file handles of linked lower/upper files (nlink = 1,2,1)
create_dirs
create_test_files $upperdir
create_test_files $lowerdir
mount_dirs
# Check encode/decode of upper file handles (nlink == 1)
test_file_handles $uppertestdir
# Check decode/read of upper file handles after link (nlink == 2)
test_file_handles $uppertestdir -wlr
# Check decode/read of upper file handles after link + unlink (nlink == 1)
test_file_handles $uppertestdir -ur
# Check encode/decode of lower file handles before copy up (nlink == 1)
test_file_handles $lowertestdir
# Check decode/read of lower file handles after copy up + link (nlink == 2)
test_file_handles $lowertestdir -wlr
# Check decode/read of lower file handles after copy up + link + unlink (nlink == 1)
test_file_handles $lowertestdir -ur
unmount_dirs

# Check non-stale file handles of linked lower/upper hardlinks (nlink = 2,1)
create_dirs
create_test_files $upperdir
create_test_files $lowerdir
# Create lower/upper hardlinks
test_file_handles $lowerdir -l >/dev/null
test_file_handles $upperdir -l >/dev/null
mount_dirs
# Check encode/decode of upper hardlink file handles (nlink == 2)
test_file_handles $uppertestdir
# Check decode/read of upper hardlink file handles after unlink (nlink == 1)
test_file_handles $uppertestdir -wur
# Check encode/decode of lower hardlink file handles before copy up (nlink == 2)
test_file_handles $lowertestdir
# Check decode/read of lower hardlink file handles after copy up + unlink (nlink == 1)
test_file_handles $lowertestdir -wur
unmount_dirs

# Check stale file handles of unlinked lower/upper hardlinks (nlink = 2,0)
create_dirs
create_test_files $upperdir
create_test_files $lowerdir
# Create lower/upper hardlinks
test_file_handles $lowerdir -l >/dev/null
test_file_handles $upperdir -l >/dev/null
mount_dirs
# Check encode/decode of upper hardlink file handles (nlink == 2)
test_file_handles $uppertestdir
# Check decode of upper hardlink file handles after 2*unlink (nlink == 0)
test_file_handles $uppertestdir -d
# Check encode/decode of lower hardlink file handles before copy up (nlink == 2)
test_file_handles $lowertestdir
# Check decode of lower hardlink file handles after copy up + 2*unlink (nlink == 0)
test_file_handles $lowertestdir -d
unmount_dirs

# Check non-stale file handles of lower/upper renamed files
create_dirs
create_test_files $upperdir
create_test_files $lowerdir
mount_dirs
# Check decode/read of upper file handles after rename in same upper parent
test_file_handles $uppertestdir -wmr
# Check decode/read of lower file handles after copy up + rename in same merge parent
test_file_handles $lowertestdir -wmr
unmount_dirs

# Check non-stale file handles of lower/upper moved files
create_dirs
create_test_files $upperdir -w
create_test_files $lowerdir -w
mkdir -p $lowerdir.lo $lowerdir.up $upperdir.lo $upperdir.up
mount_dirs
# Check encode/decode/read of lower/upper file handles after move to new upper testdir
test_file_handles $uppertestdir -o $tmp.upper_file_handles
test_file_handles $lowertestdir -o $tmp.lower_file_handles
mv $uppertestdir/* $uppertestdir.up/
mv $lowertestdir/* $uppertestdir.lo/
# Check open and read from stored file handles
test_file_handles $mnt2 -r -i $tmp.upper_file_handles
test_file_handles $mnt2 -r -i $tmp.lower_file_handles
# Check encode/decode/read of lower/upper file handles after move to new merge testdir
test_file_handles $uppertestdir.up -o $tmp.upper_file_handles
test_file_handles $uppertestdir.lo -o $tmp.lower_file_handles
mv $uppertestdir.up/* $lowertestdir.up/
mv $uppertestdir.lo/* $lowertestdir.lo/
# Check open and read from stored file handles
test_file_handles $mnt2 -r -i $tmp.upper_file_handles
test_file_handles $mnt2 -r -i $tmp.lower_file_handles
unmount_dirs

# Check non-stale file handles of lower/upper renamed dirs
create_dirs
create_test_files $upperdir -w
create_test_files $lowerdir -w
create_test_files $upperdir/subdir -w
create_test_files $lowerdir/subdir -w
mount_dirs
# Check encode/decode/read of lower/upper file handles after rename of testdir
test_file_handles $uppertestdir -p -o $tmp.upper_file_handles
test_file_handles $lowertestdir -p -o $tmp.lower_file_handles
# Check encode/decode/read of lower/upper file handles after rename of testdir's parent
test_file_handles $uppertestdir/subdir -p -o $tmp.upper_subdir_file_handles
test_file_handles $lowertestdir/subdir -p -o $tmp.lower_subdir_file_handles
# Rename pure upper dir
mv $uppertestdir $uppertestdir.new/
# Copy up lower dir, index and rename
mv $lowertestdir $lowertestdir.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 $mnt2 -rp -i $tmp.upper_file_handles
test_file_handles $mnt2 -rp -i $tmp.lower_file_handles
test_file_handles $mnt2 -rp -i $tmp.upper_subdir_file_handles
test_file_handles $mnt2 -rp -i $tmp.lower_subdir_file_handles
# Retry decoding lower subdir file handle when indexed testdir is in dcache
# (providing renamed testdir argument pins the indexed testdir to dcache)
test_file_handles $lowertestdir.new -rp -i $tmp.lower_subdir_file_handles
unmount_dirs

status=0
exit