From: Filipe Manana <fdmanana@xxxxxxxx>
Test that creating a snapshot after writing to a file using a RWF_NOWAIT
works, does not hang the snapshot creation task, and we are able to read
the data after.
Currently btrfs hangs when creating the snapshot due to a missing unlock
of a snapshot lock, but it is fixed by a patch with the following subject:
"btrfs: fix hang on snapshot creation after RWF_NOWAIT write"
Signed-off-by: Filipe Manana <fdmanana@xxxxxxxx>
---
tests/btrfs/214 | 66 +++++++++++++++++++++++++++++++++++++++++++++
tests/btrfs/214.out | 14 ++++++++++
tests/btrfs/group | 1 +
3 files changed, 81 insertions(+)
create mode 100755 tests/btrfs/214
create mode 100644 tests/btrfs/214.out
diff --git a/tests/btrfs/214 b/tests/btrfs/214
new file mode 100755
index 00000000..c835e844
--- /dev/null
+++ b/tests/btrfs/214
@@ -0,0 +1,66 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020 SUSE Linux Products GmbH. All Rights Reserved.
+#
+# FSQA Test No. 214
+#
+# Test that creating a snapshot after writing to a file using a RWF_NOWAIT
+# works, does not hang the snapshot creation task, and we are able to read
+# the data after.
+#
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+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/attr
+
+# real QA test starts here
+_supported_fs btrfs
+_supported_os Linux
+_require_scratch
+_require_odirect
+_require_xfs_io_command pwrite -N
+_require_chattr C
+
+rm -f $seqres.full
+
+_scratch_mkfs >>$seqres.full 2>&1
+_scratch_mount
+
+# RWF_NOWAIT writes require NOCOW
+touch $SCRATCH_MNT/f
+$CHATTR_PROG +C $SCRATCH_MNT/f
+
+$XFS_IO_PROG -d -c "pwrite -S 0xab 0 64K" $SCRATCH_MNT/f | _filter_xfs_io
+
+# Now do a WEF_WRITE into a range containing a NOCOWable extent.
+$XFS_IO_PROG -d -c "pwrite -N -V 1 -S 0xfe 0 64K" $SCRATCH_MNT/f \
+ | _filter_xfs_io
+
+$BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/snap \
+ | _filter_scratch
+
+# Unmount, mount again and verify the file in the subvolume and snapshot has
+# the correct data.
+_scratch_cycle_mount
+
+echo "File data in the subvolume:"
+od -A d -t x1 $SCRATCH_MNT/f
+
+echo "File data in the snapshot:"
+od -A d -t x1 $SCRATCH_MNT/snap/f
+
+status=0
+exit
diff --git a/tests/btrfs/214.out b/tests/btrfs/214.out
new file mode 100644
index 00000000..6cc66972
--- /dev/null
+++ b/tests/btrfs/214.out
@@ -0,0 +1,14 @@
+QA output created by 214
+wrote 65536/65536 bytes at offset 0
+XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 65536/65536 bytes at offset 0
+XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Create a readonly snapshot of 'SCRATCH_MNT' in 'SCRATCH_MNT/snap'
+File data in the subvolume:
+0000000 fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
+*
+0065536
+File data in the snapshot:
+0000000 fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
+*
+0065536
diff --git a/tests/btrfs/group b/tests/btrfs/group
index 9e48ecc1..a3706e7d 100644
--- a/tests/btrfs/group
+++ b/tests/btrfs/group
@@ -216,3 +216,4 @@
211 auto quick log prealloc
212 auto balance dangerous
213 auto balance dangerous
+214 auto quick snapshot
--
2.26.2
