#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2017 Red Hat, Inc.  All Rights Reserved.
#
# FS QA Test 294
#
# Test readdir on fragmented multi-fsb dir blocks
#
# If the readahead map ends with a partial multi-fsb dir
# block, the loop at the end of xfs_dir2_leaf_readbuf() may
# walk off the end of the mapping array, read garbage,
# corrupt the loop control counter, and never return.
#
# Failure is a hang; KASAN should also catch this.
#
. ./common/preamble
_begin_fstest auto dir metadata

# Import common functions.
. ./common/filter

# real QA test starts here

# Modify as appropriate.
_supported_fs xfs
_require_scratch
_require_test_program "punch-alternating"
_require_xfs_io_command "falloc"
_require_xfs_io_command "fpunch"

# We want to mkfs with a very specific geometry
MKFS_OPTIONS=""
_scratch_mkfs "-d size=512m -n size=8192 -i size=1024" >> $seqres.full 2>&1 \
	|| _fail "mkfs failed"
_scratch_mount

# Make a ton of mostly-empty inode clusters so we can always
# make more inodes
mkdir $SCRATCH_MNT/tmp
for I in `seq 1 10000`; do touch $SCRATCH_MNT/tmp/$I; done

# These mostly-empty clusters will live here:
mkdir $SCRATCH_MNT/clusters
for I in `seq 1 32 10000`; do
	mv $SCRATCH_MNT/tmp/$I $SCRATCH_MNT/clusters;
done
rm -rf $SCRATCH_MNT/tmp

# Make our test dir with a couple blocks, should be contiguous
mkdir $SCRATCH_MNT/testdir
# roughly 20 chars per file
for I in `seq 1 100`; do
	touch $SCRATCH_MNT/testdir/12345678901234567890$I;
done

# File to fragment:
$XFS_IO_PROG -f -c "falloc 0 70m" $SCRATCH_MNT/fragfile ||
	_fail "Could not allocate space"

# Now completely fragment freespace.
# Consume most of it:
space=$(stat -f -c '%f * %S * 95 / 100' $SCRATCH_MNT | $BC_PROG)
$XFS_IO_PROG -f -c "falloc 0 $space" $SCRATCH_MNT/fillfile ||
	_fail "Could not allocate space"

df -h $SCRATCH_MNT >> $seqres.full 2>&1

# Fill remaining space; let this run to failure
dd if=/dev/zero of=$SCRATCH_MNT/spacefile1 oflag=direct >> $seqres.full 2>&1
# Fragment our all-consuming file
$here/src/punch-alternating $SCRATCH_MNT/fragfile >> $seqres.full 2>&1

# Punching might have freed up large-ish swaths of metadata
# Consume hopefully any remaining contiguous freespace
# (and then some for good measure)
dd conv=fsync if=/dev/zero of=$SCRATCH_MNT/spacefile2 bs=1M count=64 >> $seqres.full 2>&1

# Now populate the directory so that it must allocate these
# fragmented blocks
for I in `seq 1 1400`; do
	touch $SCRATCH_MNT/testdir/12345678901234567890$I;
done

# Now traverse that ugly thing!
find $SCRATCH_MNT/testdir | sort | _filter_scratch | md5sum

status=0
exit