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Block layer patches:

Browse source 
- Fix internal snapshots with typical -blockdev setups
 - iotests: Require Python 3.6 or later
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches:

- Fix internal snapshots with typical -blockdev setups
- iotests: Require Python 3.6 or later

# gpg: Signature made Fri 04 Oct 2019 10:59:21 BST
# gpg:                using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream:
  iotests: Remove Python 2 compatibility code
  iotests: Require Python 3.6 or later
  iotests: Test internal snapshots with -blockdev
  block/snapshot: Restrict set of snapshot nodes

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Peter Maydell 2019-10-07 15:40:53 +01:00
parent 0f0b43868a 7e693a0500
commit 560009f2c8
9 changed files with 392 additions and 28 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

26
block/snapshot.c
View file

@ -31,6 +31,7 @@
#include "qapi/qmp/qerror.h"
#include "qapi/qmp/qstring.h"
#include "qemu/option.h"
#include "sysemu/block-backend.h"
QemuOptsList internal_snapshot_opts = {
.name = "snapshot",
@ -384,6 +385,16 @@ int bdrv_snapshot_load_tmp_by_id_or_name(BlockDriverState *bs,
return ret;
}
static bool bdrv_all_snapshots_includes_bs(BlockDriverState *bs)
{
if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
return false;
}
/* Include all nodes that are either in use by a BlockBackend, or that
* aren't attached to any node, but owned by the monitor. */
return bdrv_has_blk(bs) || QLIST_EMPTY(&bs->parents);
}
/* Group operations. All block drivers are involved.
* These functions will properly handle dataplane (take aio_context_acquire
@ -399,7 +410,7 @@ bool bdrv_all_can_snapshot(BlockDriverState **first_bad_bs)
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
if (bdrv_is_inserted(bs) && !bdrv_is_read_only(bs)) {
if (bdrv_all_snapshots_includes_bs(bs)) {
ok = bdrv_can_snapshot(bs);
}
aio_context_release(ctx);
@ -426,8 +437,9 @@ int bdrv_all_delete_snapshot(const char *name, BlockDriverState **first_bad_bs,
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
if (bdrv_can_snapshot(bs) &&
bdrv_snapshot_find(bs, snapshot, name) >= 0) {
if (bdrv_all_snapshots_includes_bs(bs) &&
bdrv_snapshot_find(bs, snapshot, name) >= 0)
{
ret = bdrv_snapshot_delete(bs, snapshot->id_str,
snapshot->name, err);
}
@ -455,7 +467,7 @@ int bdrv_all_goto_snapshot(const char *name, BlockDriverState **first_bad_bs,
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
if (bdrv_can_snapshot(bs)) {
if (bdrv_all_snapshots_includes_bs(bs)) {
ret = bdrv_snapshot_goto(bs, name, errp);
}
aio_context_release(ctx);
@ -481,7 +493,7 @@ int bdrv_all_find_snapshot(const char *name, BlockDriverState **first_bad_bs)
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
if (bdrv_can_snapshot(bs)) {
if (bdrv_all_snapshots_includes_bs(bs)) {
err = bdrv_snapshot_find(bs, &sn, name);
}
aio_context_release(ctx);
@ -512,7 +524,7 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
if (bs == vm_state_bs) {
sn->vm_state_size = vm_state_size;
err = bdrv_snapshot_create(bs, sn);
} else if (bdrv_can_snapshot(bs)) {
} else if (bdrv_all_snapshots_includes_bs(bs)) {
sn->vm_state_size = 0;
err = bdrv_snapshot_create(bs, sn);
}
@ -538,7 +550,7 @@ BlockDriverState *bdrv_all_find_vmstate_bs(void)
bool found;
aio_context_acquire(ctx);
found = bdrv_can_snapshot(bs);
found = bdrv_all_snapshots_includes_bs(bs) && bdrv_can_snapshot(bs);
aio_context_release(ctx);
if (found) {

3
tests/qemu-iotests/044
View file

@ -28,9 +28,6 @@ import struct
import subprocess
import sys
if sys.version_info.major == 2:
range = xrange
test_img = os.path.join(iotests.test_dir, 'test.img')
class TestRefcountTableGrowth(iotests.QMPTestCase):

3
tests/qemu-iotests/163
View file

@ -21,9 +21,6 @@
import os, random, iotests, struct, qcow2, sys
from iotests import qemu_img, qemu_io, image_size
if sys.version_info.major == 2:
range = xrange
test_img = os.path.join(iotests.test_dir, 'test.img')
check_img = os.path.join(iotests.test_dir, 'check.img')

168
tests/qemu-iotests/267 Executable file
View file

@ -0,0 +1,168 @@
#!/usr/bin/env bash
#
# Test which nodes are involved in internal snapshots
#
# Copyright (C) 2019 Red Hat, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# creator
owner=kwolf@redhat.com
seq=`basename $0`
echo "QA output created by $seq"
status=1 # failure is the default!
_cleanup()
{
_cleanup_test_img
rm -f "$TEST_DIR/nbd"
}
trap "_cleanup; exit \$status" 0 1 2 3 15
# get standard environment, filters and checks
. ./common.rc
. ./common.filter
_supported_fmt qcow2
_supported_proto file
_supported_os Linux
# Internal snapshots are (currently) impossible with refcount_bits=1
_unsupported_imgopts 'refcount_bits=1[^0-9]'
do_run_qemu()
{
echo Testing: "$@"
(
if ! test -t 0; then
while read cmd; do
echo $cmd
done
fi
echo quit
) | $QEMU -nographic -monitor stdio -nodefaults "$@"
echo
}
run_qemu()
{
do_run_qemu "$@" 2>&1 | _filter_testdir | _filter_qemu | _filter_hmp |
_filter_generated_node_ids | _filter_imgfmt | _filter_vmstate_size
}
size=128M
run_test()
{
_make_test_img $size
printf "savevm snap0\ninfo snapshots\nloadvm snap0\n" | run_qemu "$@" | _filter_date
}
echo
echo "=== No block devices at all ==="
echo
run_test
echo
echo "=== -drive if=none ==="
echo
run_test -drive driver=file,file="$TEST_IMG",if=none
run_test -drive driver=$IMGFMT,file="$TEST_IMG",if=none
run_test -drive driver=$IMGFMT,file="$TEST_IMG",if=none -device virtio-blk,drive=none0
echo
echo "=== -drive if=virtio ==="
echo
run_test -drive driver=file,file="$TEST_IMG",if=virtio
run_test -drive driver=$IMGFMT,file="$TEST_IMG",if=virtio
echo
echo "=== Simple -blockdev ==="
echo
run_test -blockdev driver=file,filename="$TEST_IMG",node-name=file
run_test -blockdev driver=file,filename="$TEST_IMG",node-name=file \
-blockdev driver=$IMGFMT,file=file,node-name=fmt
run_test -blockdev driver=file,filename="$TEST_IMG",node-name=file \
-blockdev driver=raw,file=file,node-name=raw \
-blockdev driver=$IMGFMT,file=raw,node-name=fmt
echo
echo "=== -blockdev with a filter on top ==="
echo
run_test -blockdev driver=file,filename="$TEST_IMG",node-name=file \
-blockdev driver=$IMGFMT,file=file,node-name=fmt \
-blockdev driver=copy-on-read,file=fmt,node-name=filter
echo
echo "=== -blockdev with a backing file ==="
echo
TEST_IMG="$TEST_IMG.base" _make_test_img $size
IMGOPTS="backing_file=$TEST_IMG.base" \
run_test -blockdev driver=file,filename="$TEST_IMG.base",node-name=backing-file \
-blockdev driver=file,filename="$TEST_IMG",node-name=file \
-blockdev driver=$IMGFMT,file=file,backing=backing-file,node-name=fmt
IMGOPTS="backing_file=$TEST_IMG.base" \
run_test -blockdev driver=file,filename="$TEST_IMG.base",node-name=backing-file \
-blockdev driver=$IMGFMT,file=backing-file,node-name=backing-fmt \
-blockdev driver=file,filename="$TEST_IMG",node-name=file \
-blockdev driver=$IMGFMT,file=file,backing=backing-fmt,node-name=fmt
# A snapshot should be present on the overlay, but not the backing file
echo Internal snapshots on overlay:
$QEMU_IMG snapshot -l "$TEST_IMG" | _filter_date | _filter_vmstate_size
echo Internal snapshots on backing file:
$QEMU_IMG snapshot -l "$TEST_IMG.base" | _filter_date | _filter_vmstate_size
echo
echo "=== -blockdev with NBD server on the backing file ==="
echo
IMGOPTS="backing_file=$TEST_IMG.base" _make_test_img $size
cat <<EOF |
nbd_server_start unix:$TEST_DIR/nbd
nbd_server_add -w backing-fmt
savevm snap0
info snapshots
loadvm snap0
EOF
run_qemu -blockdev driver=file,filename="$TEST_IMG.base",node-name=backing-file \
-blockdev driver=$IMGFMT,file=backing-file,node-name=backing-fmt \
-blockdev driver=file,filename="$TEST_IMG",node-name=file \
-blockdev driver=$IMGFMT,file=file,backing=backing-fmt,node-name=fmt |
_filter_date
# This time, a snapshot should be created on both files
echo Internal snapshots on overlay:
$QEMU_IMG snapshot -l "$TEST_IMG" | _filter_date | _filter_vmstate_size
echo Internal snapshots on backing file:
$QEMU_IMG snapshot -l "$TEST_IMG.base" | _filter_date | _filter_vmstate_size
# success, all done
echo "*** done"
rm -f $seq.full
status=0

182
tests/qemu-iotests/267.out Normal file
View file

@ -0,0 +1,182 @@
QA output created by 267
=== No block devices at all ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing:
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
Error: No block device can accept snapshots
(qemu) info snapshots
No available block device supports snapshots
(qemu) loadvm snap0
Error: No block device supports snapshots
(qemu) quit
=== -drive if=none ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -drive driver=file,file=TEST_DIR/t.IMGFMT,if=none
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
Error: Device 'none0' is writable but does not support snapshots
(qemu) info snapshots
No available block device supports snapshots
(qemu) loadvm snap0
Error: Device 'none0' is writable but does not support snapshots
(qemu) quit
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -drive driver=IMGFMT,file=TEST_DIR/t.IMGFMT,if=none
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -drive driver=IMGFMT,file=TEST_DIR/t.IMGFMT,if=none -device virtio-blk,drive=none0
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
=== -drive if=virtio ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -drive driver=file,file=TEST_DIR/t.IMGFMT,if=virtio
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
Error: Device 'virtio0' is writable but does not support snapshots
(qemu) info snapshots
No available block device supports snapshots
(qemu) loadvm snap0
Error: Device 'virtio0' is writable but does not support snapshots
(qemu) quit
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -drive driver=IMGFMT,file=TEST_DIR/t.IMGFMT,if=virtio
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
=== Simple -blockdev ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=file
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
Error: Device '' is writable but does not support snapshots
(qemu) info snapshots
No available block device supports snapshots
(qemu) loadvm snap0
Error: Device '' is writable but does not support snapshots
(qemu) quit
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=file -blockdev driver=IMGFMT,file=file,node-name=fmt
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=file -blockdev driver=raw,file=file,node-name=raw -blockdev driver=IMGFMT,file=raw,node-name=fmt
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
=== -blockdev with a filter on top ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
Testing: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=file -blockdev driver=IMGFMT,file=file,node-name=fmt -blockdev driver=copy-on-read,file=fmt,node-name=filter
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
=== -blockdev with a backing file ===
Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=134217728
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/t.IMGFMT.base
Testing: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT.base,node-name=backing-file -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=file -blockdev driver=IMGFMT,file=file,backing=backing-file,node-name=fmt
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/t.IMGFMT.base
Testing: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT.base,node-name=backing-file -blockdev driver=IMGFMT,file=backing-file,node-name=backing-fmt -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=file -blockdev driver=IMGFMT,file=file,backing=backing-fmt,node-name=fmt
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
Internal snapshots on overlay:
Snapshot list:
ID TAG VM SIZE DATE VM CLOCK
1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
Internal snapshots on backing file:
=== -blockdev with NBD server on the backing file ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/t.IMGFMT.base
Testing: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT.base,node-name=backing-file -blockdev driver=IMGFMT,file=backing-file,node-name=backing-fmt -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=file -blockdev driver=IMGFMT,file=file,backing=backing-fmt,node-name=fmt
QEMU X.Y.Z monitor - type 'help' for more information
(qemu) nbd_server_start unix:TEST_DIR/nbd
(qemu) nbd_server_add -w backing-fmt
(qemu) savevm snap0
(qemu) info snapshots
List of snapshots present on all disks:
ID TAG VM SIZE DATE VM CLOCK
-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
(qemu) loadvm snap0
(qemu) quit
Internal snapshots on overlay:
Snapshot list:
ID TAG VM SIZE DATE VM CLOCK
1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
Internal snapshots on backing file:
Snapshot list:
ID TAG VM SIZE DATE VM CLOCK
1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000
*** done

13
tests/qemu-iotests/check
View file

@ -633,6 +633,12 @@ then
export SOCKET_SCM_HELPER="$build_iotests/socket_scm_helper"
fi
python_usable=false
if $PYTHON -c 'import sys; sys.exit(0 if sys.version_info >= (3,6) else 1)'
then
python_usable=true
fi
default_machine=$($QEMU_PROG -machine help | sed -n '/(default)/ s/ .*//p')
default_alias_machine=$($QEMU_PROG -machine help | \
sed -n "/(alias of $default_machine)/ { s/ .*//p; q; }")
@ -809,7 +815,12 @@ do
start=$(_wallclock)
if [ "$(head -n 1 "$source_iotests/$seq")" == "#!/usr/bin/env python" ]; then
run_command="$PYTHON $seq"
if $python_usable; then
run_command="$PYTHON $seq"
else
run_command="false"
echo "Unsupported Python version" > $seq.notrun
fi
else
run_command="./$seq"
fi

11
tests/qemu-iotests/common.filter
View file

@ -19,12 +19,15 @@
# standard filters
#
# ctime(3) dates
#
_filter_date()
{
$SED \
-e 's/[A-Z][a-z][a-z] [A-z][a-z][a-z] *[0-9][0-9]* [0-9][0-9]:[0-9][0-9]:[0-9][0-9] [0-9][0-9][0-9][0-9]$/DATE/'
$SED -re 's/[0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2}/yyyy-mm-dd hh:mm:ss/'
}
_filter_vmstate_size()
{
$SED -r -e 's/[0-9. ]{5} [KMGT]iB/ SIZE/' \
-e 's/[0-9. ]{5} B/ SIZE/'
}
_filter_generated_node_ids()

1
tests/qemu-iotests/group
View file

@ -277,3 +277,4 @@
263 rw quick
265 rw auto quick
266 rw quick
267 rw auto quick snapshot

13
tests/qemu-iotests/iotests.py
View file

@ -35,6 +35,7 @@ from collections import OrderedDict
sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..', 'python'))
from qemu import qtest
assert sys.version_info >= (3,6)
# This will not work if arguments contain spaces but is necessary if we
# want to support the override options that ./check supports.
@ -250,10 +251,7 @@ def image_size(img):
return json.loads(r)['virtual-size']
def is_str(val):
if sys.version_info.major >= 3:
return isinstance(val, str)
else:
return isinstance(val, str) or isinstance(val, unicode)
return isinstance(val, str)
test_dir_re = re.compile(r"%s" % test_dir)
def filter_test_dir(msg):
@ -935,12 +933,7 @@ def execute_test(test_function=None,
else:
# We need to filter out the time taken from the output so that
# qemu-iotest can reliably diff the results against master output.
if sys.version_info.major >= 3:
output = io.StringIO()
else:
# io.StringIO is for unicode strings, which is not what
# 2.x's test runner emits.
output = io.BytesIO()
output = io.StringIO()
logging.basicConfig(level=(logging.DEBUG if debug else logging.WARN))