[PATCH] xfstests: rename RENAME_WHITEOUT test on fs no enough sapce

[Zorro Lang <zlang@redhat.com>]

This's a regression test for linux 6b4b8e6b4ad8 ("ext4: fix bug for
rename with RENAME_WHITEOUT"). Rename a file with RENAME_WHITEOUT
flag might cause corruption when there's not enough space to
complete this renaming operation.

Signed-off-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Sun Ke <sunke32@huawei.com>
---

Hi,

As the request of Sun Ke, I rewrite his test case as this patch.
The history of reviewing as below:
https://patchwork.kernel.org/project/fstests/patch/20210128061202.210074-1-sunke32@huawei.com/
https://patchwork.kernel.org/project/fstests/patch/20210202123956.3146761-1-sunke32@huawei.com/

At last, I decide to create several chunks of files to do this testing, help to
get more chance to trigger ENOSPC when does rename(RENAME_WHITEOUT).

From my testing, it can reproduce this bug on linux 5.10[1], and test passed on
linux 5.11-rc5+ [2]. And it works on XFS too. Hope to get more review from fs-devel.

[1]
# ./check generic/623
FSTYP         -- ext4
PLATFORM      -- Linux/x86_64 ibm-xxxxxxx-xx 5.10.0-rc5+ #4 SMP Tue Jan 5 20:12:45 CST 2021
MKFS_OPTIONS  -- /dev/mapper/testvg-scratchdev
MOUNT_OPTIONS -- -o acl,user_xattr -o context=system_u:object_r:root_t:s0 /dev/mapper/testvg-scratchdev /mnt/scratch

generic/623     _check_generic_filesystem: filesystem on /dev/mapper/testvg-scratchdev is inconsistent                                                                                        
(see /root/git/xfstests-zlang/results//generic/623.full for details)
- output mismatch (see /root/git/xfstests-zlang/results//generic/623.out.bad)
    --- tests/generic/623.out   2021-02-18 13:26:35.953071523 +0800
    +++ /root/git/xfstests-zlang/results//generic/623.out.bad   2021-02-18 13:28:10.450733088 +0800                                                                                           
    @@ -1,2 +1,232 @@
     QA output created by 623
    +ls: cannot access '/mnt/scratch/srcfile3866': Structure needs cleaning
    +ls: cannot access '/mnt/scratch/srcfile3867': Structure needs cleaning
    +ls: cannot access '/mnt/scratch/srcfile3868': Structure needs cleaning
    +ls: cannot access '/mnt/scratch/srcfile3869': Structure needs cleaning
    +ls: cannot access '/mnt/scratch/srcfile3870': Structure needs cleaning
    +ls: cannot access '/mnt/scratch/srcfile3871': Structure needs cleaning
    ...
    (Run 'diff -u /root/git/xfstests-zlang/tests/generic/623.out /root/git/xfstests-zlang/results//generic/623.out.bad'  to see the entire diff)                                              
Ran: generic/623
Failures: generic/623
Failed 1 of 1 tests

[2]
# ./check generic/623
FSTYP         -- ext4
PLATFORM      -- Linux/x86_64 localhost 5.11.0-0.rc5.20210128git76c057c84d28.137.fc34.x86_64 #1 SMP Thu Jan 28 21:10:47 UTC 2021
MKFS_OPTIONS  -- /dev/mapper/testvg-scratchdev
MOUNT_OPTIONS -- -o acl,user_xattr -o context=system_u:object_r:root_t:s0 /dev/mapper/testvg-scratchdev /mnt/scratch

generic/623 4s ...  86s
Ran: generic/623
Passed all 1 tests

[3]
# ./check generic/623
FSTYP         -- xfs (non-debug)
PLATFORM      -- Linux/x86_64 localhost 5.11.0-0.rc5.20210128git76c057c84d28.137.fc34.x86_64 #1 SMP Thu Jan 28 21:10:47 UTC 2021
MKFS_OPTIONS  -- -f -bsize=4096 /dev/mapper/testvg-scratchdev
MOUNT_OPTIONS -- -o context=system_u:object_r:root_t:s0 /dev/mapper/testvg-scratchdev /mnt/scratch

generic/623 86s ...  99s
Ran: generic/623
Passed all 1 tests

Thanks,
Zorro

 tests/generic/623     | 72 +++++++++++++++++++++++++++++++++++++++++++
 tests/generic/623.out |  2 ++
 tests/generic/group   |  1 +
 3 files changed, 75 insertions(+)
 create mode 100755 tests/generic/623
 create mode 100644 tests/generic/623.out

diff --git a/tests/generic/623 b/tests/generic/623
new file mode 100755
index 00000000..56358ca6
--- /dev/null
+++ b/tests/generic/623
@@ -0,0 +1,72 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2021 HUAWEI.  All Rights Reserved.
+# Copyright (c) 2021 Red Hat Inc.  All Rights Reserved.
+#
+# FS QA Test 623
+#
+# Test RENAME_WHITEOUT on filesystem without space to create one more inodes.
+# This is a regression test for kernel commit:
+#   6b4b8e6b4ad8 ("ext4: ext4: fix bug for rename with RENAME_WHITEOUT")
+#
+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.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/populate
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# real QA test starts here
+_supported_fs generic
+_require_scratch
+
+_scratch_mkfs_sized $((256 * 1024 * 1024)) >> $seqres.full 2>&1
+_scratch_mount
+
+# Create several chunks of file, to help to trigger the bug easily
+CHUNKS=$((64 * 64))
+for ((i=0; i<CHUNKS; i++));do
+	touch $SCRATCH_MNT/srcfile$i
+done
+# Try to fill the whole fs
+nr_free=$(stat -f -c '%f' $SCRATCH_MNT)
+blksz="$(_get_block_size $SCRATCH_MNT)"
+_fill_fs $((nr_free * blksz)) $SCRATCH_MNT/fill_space $blksz 0 >> $seqres.full 2>&1
+# Use empty files to fill the rest
+for ((i=0; i<10000; i++));do
+	touch $SCRATCH_MNT/fill_file$i 2>/dev/null
+	# Until no more files can be created
+	if [ $? -ne 0 ];then
+		break
+	fi
+done
+# ENOSPC is expected here
+for ((i=0; i<CHUNKS; i++));do
+	$here/src/renameat2 -w $SCRATCH_MNT/srcfile$i $SCRATCH_MNT/dstfile$i >> $seqres.full 2>&1
+done
+_scratch_cycle_mount
+# Expect no errors at here
+for ((i=0; i<CHUNKS; i++));do
+	ls -l $SCRATCH_MNT/srcfile$i >/dev/null
+done
+
+echo "Silence is golden"
+# success, all done
+status=0
+exit
diff --git a/tests/generic/623.out b/tests/generic/623.out
new file mode 100644
index 00000000..6f774f19
--- /dev/null
+++ b/tests/generic/623.out
@@ -0,0 +1,2 @@
+QA output created by 623
+Silence is golden
diff --git a/tests/generic/group b/tests/generic/group
index b10fdea4..72136075 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -625,3 +625,4 @@
 620 auto mount quick
 621 auto quick encrypt
 622 auto shutdown metadata atime
+623 auto rename enospc
-- 
2.29.2