openstack/deb-cinder
Code Issues Proposed changes

vzstorage: fix create/delete snapshots

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vzstorage doesn't support simultaneous open from different
clients. It means you can't open qcow2 file from cinder-volume
side, if it's used by an instance on nova-compute side.
The solution is to cache QemuImgInfo instance
under <path>.qemu_img_cache for image file <path>

Closes-Bug: #1615667
Change-Id: I8949ddc244e0eef699b2af224303f86507f6f30e
Co-Authored-By: Evgeny Antyshev <eantyshev@virtuozzo.com>
This commit is contained in:
Dmitry Guryanov 2016-02-04 16:51:10 -05:00 committed by Evgeny Antyshev
parent 175667cf4e
commit 79b3a92e63
4 changed files with 148 additions and 46 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
cinder/tests/unit/volume/drivers/test_remotefs.py
View File

@ -208,8 +208,11 @@ class RemoteFsSnapDriverTestCase(test.TestCase):
self._fake_volume.name,
self._fake_snapshot_path)
command1 = ['qemu-img', 'create', '-f', 'qcow2', '-o',
'backing_file=%s' % fake_backing_path,
self._fake_snapshot_path]
'backing_file=%s,backing_fmt=%s' %
(fake_backing_path,
mock.sentinel.backing_fmt),
self._fake_snapshot_path,
"%dG" % self._fake_volume.size]
command2 = ['qemu-img', 'rebase', '-u',
'-b', self._fake_volume.name,
'-F', mock.sentinel.backing_fmt,

20
cinder/tests/unit/volume/drivers/test_vzstorage.py
View File

@ -216,13 +216,14 @@ class VZStorageTestCase(test.TestCase):
drv._check_extend_volume_support = mock.Mock(return_value=True)
drv._is_file_size_equal = mock.Mock(return_value=True)
snap_info = """{"volume_format": "raw",
"active": "%s"}""" % self.vol.id
with mock.patch.object(drv, 'local_path',
return_value=self._FAKE_VOLUME_PATH):
with mock.patch.object(drv, '_read_file',
return_value=snap_info):
drv.extend_volume(self.vol, 10)
snap_info = '{"active": "%s"}' % self.vol.id
with mock.patch.object(drv, 'get_volume_format',
return_value="raw"):
with mock.patch.object(drv, 'local_path',
return_value=self._FAKE_VOLUME_PATH):
with mock.patch.object(drv, '_read_file',
return_value=snap_info):
drv.extend_volume(self.vol, 10)
mock_resize_image.assert_called_once_with(self._FAKE_VOLUME_PATH, 10)
@ -263,7 +264,10 @@ class VZStorageTestCase(test.TestCase):
def test_copy_volume_from_snapshot(self, mock_convert_image):
drv = self._vz_driver
fake_volume_info = {self._FAKE_SNAPSHOT_ID: 'fake_snapshot_file_name'}
fake_volume_info = {self._FAKE_SNAPSHOT_ID: 'fake_snapshot_file_name',
'backing-files':
{self._FAKE_SNAPSHOT_ID:
self._FAKE_VOLUME_NAME}}
fake_img_info = mock.MagicMock()
fake_img_info.backing_file = self._FAKE_VOLUME_NAME

40
cinder/volume/drivers/remotefs.py
View File

@ -747,6 +747,24 @@ class RemoteFSSnapDriverBase(RemoteFSDriver, driver.SnapshotVD):
return json.loads(self._read_file(info_path))
def _get_higher_image_path(self, snapshot):
volume = snapshot.volume
info_path = self._local_path_volume_info(volume)
snap_info = self._read_info_file(info_path)
snapshot_file = snap_info[snapshot.id]
active_file = self.get_active_image_from_info(volume)
active_file_path = os.path.join(self._local_volume_dir(volume),
active_file)
backing_chain = self._get_backing_chain_for_path(
volume, active_file_path)
higher_file = next((os.path.basename(f['filename'])
for f in backing_chain
if f.get('backing-filename', '') ==
snapshot_file),
None)
return higher_file
def _get_backing_chain_for_path(self, volume, path):
"""Returns list of dicts containing backing-chain information.
@ -1018,7 +1036,6 @@ class RemoteFSSnapDriverBase(RemoteFSDriver, driver.SnapshotVD):
# Find what file has this as its backing file
active_file = self.get_active_image_from_info(snapshot.volume)
active_file_path = os.path.join(vol_path, active_file)
if volume_status == 'in-use':
# Online delete
@ -1065,15 +1082,9 @@ class RemoteFSSnapDriverBase(RemoteFSDriver, driver.SnapshotVD):
# exist, not | committed down) | exist, needs |
# used here) | | ptr update) |
backing_chain = self._get_backing_chain_for_path(
snapshot.volume, active_file_path)
# This file is guaranteed to exist since we aren't operating on
# the active file.
higher_file = next((os.path.basename(f['filename'])
for f in backing_chain
if f.get('backing-filename', '') ==
snapshot_file),
None)
higher_file = self._get_higher_image_path(snapshot)
if higher_file is None:
msg = _('No file found with %s as backing file.') %\
snapshot_file
@ -1132,19 +1143,20 @@ class RemoteFSSnapDriverBase(RemoteFSDriver, driver.SnapshotVD):
new qcow2 file
:param new_snap_path: filename of new qcow2 file
"""
backing_path_full_path = os.path.join(
self._local_volume_dir(snapshot.volume),
backing_filename)
command = ['qemu-img', 'create', '-f', 'qcow2', '-o',
'backing_file=%s' % backing_path_full_path, new_snap_path]
self._execute(*command, run_as_root=self._execute_as_root)
info = self._qemu_img_info(backing_path_full_path,
snapshot.volume.name)
backing_fmt = info.file_format
command = ['qemu-img', 'create', '-f', 'qcow2', '-o',
'backing_file=%s,backing_fmt=%s' %
(backing_path_full_path, backing_fmt),
new_snap_path,
"%dG" % snapshot.volume.size]
self._execute(*command, run_as_root=self._execute_as_root)
command = ['qemu-img', 'rebase', '-u',
'-b', backing_filename,
'-F', backing_fmt,

127
cinder/volume/drivers/vzstorage.py
View File

@ -23,6 +23,7 @@ from os_brick.remotefs import remotefs
from oslo_concurrency import processutils as putils
from oslo_config import cfg
from oslo_log import log as logging
from oslo_utils import imageutils
from oslo_utils import units
from cinder import exception
@ -158,8 +159,31 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
vzstorage_mount_options=opts)
def _qemu_img_info(self, path, volume_name):
return super(VZStorageDriver, self)._qemu_img_info_base(
path, volume_name, self.configuration.vzstorage_mount_point_base)
qemu_img_cache = path + ".qemu_img_info"
if os.path.isdir(path):
# 'parallels' disks stored along with metadata xml as directories
# qemu-img should explore base data file inside
path = os.path.join(path, PLOOP_BASE_DELTA_NAME)
if os.path.isfile(qemu_img_cache):
info_tm = os.stat(qemu_img_cache).st_mtime
snap_tm = os.stat(path).st_mtime
ret = None
if not os.path.isfile(qemu_img_cache) or snap_tm > info_tm:
LOG.debug("Cached qemu-img info %s not present or outdated,"
" refresh", qemu_img_cache)
ret = super(VZStorageDriver, self)._qemu_img_info_base(
path, volume_name,
self.configuration.vzstorage_mount_point_base)
# We need only backing_file and file_format
d = {'file_format': ret.file_format,
'backing_file': ret.backing_file}
with open(qemu_img_cache, "w") as f:
json.dump(d, f)
else:
ret = imageutils.QemuImgInfo()
with open(qemu_img_cache, "r") as f:
ret.__dict__ = json.load(f)
return ret
@remotefs_drv.locked_volume_id_operation
def initialize_connection(self, volume, connector):
@ -297,9 +321,12 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
self.configuration.vzstorage_default_volume_format)
def get_volume_format(self, volume):
info_path = self._local_path_volume_info(volume)
snap_info = self._read_info_file(info_path)
return snap_info['volume_format']
active_file = self.get_active_image_from_info(volume)
active_file_path = os.path.join(self._local_volume_dir(volume),
active_file)
img_info = self._qemu_img_info(active_file_path, volume.name)
return img_info.file_format
def _create_ploop(self, volume_path, volume_size):
os.mkdir(volume_path)
@ -312,7 +339,7 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
raise
def _do_create_volume(self, volume):
"""Create a volume on given smbfs_share.
"""Create a volume on given vzstorage share.
:param volume: volume reference
"""
@ -337,10 +364,12 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
self._create_regular_file(volume_path, volume_size)
info_path = self._local_path_volume_info(volume)
snap_info = {'volume_format': volume_format,
'active': 'volume-%s' % volume.id}
snap_info = {'active': os.path.basename(volume_path)}
self._write_info_file(info_path, snap_info)
# Query qemu-img info to cache the output
self._qemu_img_info(volume_path, volume.name)
def _delete(self, path):
self._execute('rm', '-rf', path, run_as_root=True)
@ -418,6 +447,8 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
self._do_extend_volume(self.local_path(volume),
volume.size,
volume_format)
# Query qemu-img info to cache the output
self._qemu_img_info(self.local_path(volume), volume.name)
def _copy_volume_from_snapshot(self, snapshot, volume, volume_size):
"""Copy data from snapshot to destination volume.
@ -453,19 +484,15 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
with PloopDevice(self.local_path(snapshot.volume),
snapshot.id,
execute=self._execute) as dev:
image_utils.convert_image(dev, volume_path, out_format)
base_file = os.path.join(volume_path, 'root.hds')
image_utils.convert_image(dev, base_file, out_format)
else:
msg = _("Unsupported volume format %s") % volume_format
raise exception.InvalidVolume(msg)
if out_format == DISK_FORMAT_PLOOP:
img_path = os.path.join(volume_path, 'root.hds')
os.rename(volume_path, volume_path + '.tmp')
os.mkdir(volume_path)
os.rename(volume_path + '.tmp', img_path)
self._execute('ploop', 'restore-descriptor', volume_path, img_path)
self._extend_volume(volume, volume_size, out_format)
# Query qemu-img info to cache the output
img_info = self._qemu_img_info(volume_path, volume.name)
@remotefs_drv.locked_volume_id_operation
def delete_volume(self, volume):
@ -475,7 +502,6 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
'specified, skipping.') % volume.name)
LOG.error(msg)
return
# raise exception.VzStorageException(msg)
self._ensure_share_mounted(volume.provider_location)
volume_dir = self._local_volume_dir(volume)
@ -483,6 +509,7 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
self.get_active_image_from_info(volume))
if os.path.exists(mounted_path):
self._delete(mounted_path)
self._delete(mounted_path + ".qemu_img_info")
else:
LOG.info(_LI("Skipping deletion of volume %s "
"as it does not exist."), mounted_path)
@ -533,13 +560,69 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
else:
super(VZStorageDriver, self)._create_snapshot(snapshot)
def _do_create_snapshot(self, snapshot, backing_filename,
new_snap_path):
super(VZStorageDriver, self)._do_create_snapshot(snapshot,
backing_filename,
new_snap_path)
# Cache qemu-img info for created snapshot
self._qemu_img_info(new_snap_path, snapshot.volume.name)
def delete_snapshot(self, snapshot):
info_path = self._local_path_volume_info(snapshot.volume)
snap_info = self._read_info_file(info_path, empty_if_missing=True)
snap_file = os.path.join(self._local_volume_dir(snapshot.volume),
snap_info[snapshot.id])
active_file = os.path.join(self._local_volume_dir(snapshot.volume),
snap_info['active'])
higher_file = self._get_higher_image_path(snapshot)
if higher_file:
higher_file = os.path.join(self._local_volume_dir(snapshot.volume),
higher_file)
elif active_file != snap_file:
msg = (_("Expected higher file exists for snapshot %s") %
snapshot.id)
raise exception.VzStorageException(msg)
img_info = self._qemu_img_info(snap_file, snapshot.volume.name)
base_file = os.path.join(self._local_volume_dir(snapshot.volume),
img_info.backing_file)
volume_format = self.get_volume_format(snapshot.volume)
online = snapshot.volume.status == 'in-use'
if volume_format == 'parallels':
self._delete_snapshot_ploop(snapshot)
else:
super(VZStorageDriver, self)._delete_snapshot(snapshot)
def _qemu_info_cache(fn):
return fn + ".qemu_img_info"
def _update_backing_file(info_src, info_dst):
with open(info_src, 'r') as fs, open(info_dst, 'r') as fd:
src = json.load(fs)
dst = json.load(fd)
dst['backing_file'] = src['backing_file']
with open(info_dst, 'w') as fdw:
json.dump(dst, fdw)
if volume_format == "qcow2":
if snap_file != active_file:
# mv snap_file.info higher_file.info
_update_backing_file(
_qemu_info_cache(snap_file),
_qemu_info_cache(higher_file))
self._delete(_qemu_info_cache(snap_file))
elif online:
# mv base_file.info snap_file.info
_update_backing_file(
_qemu_info_cache(base_file),
_qemu_info_cache(snap_file))
self._delete(_qemu_info_cache(base_file))
else:
# rm snap_file.info
self._delete(_qemu_info_cache(snap_file))
def _copy_volume_to_image(self, context, volume, image_service,
image_meta):
"""Copy the volume to the specified image."""
@ -586,8 +669,7 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
try:
volume.provider_location = src_vref.provider_location
info_path = self._local_path_volume_info(volume)
snap_info = {'volume_format': DISK_FORMAT_PLOOP,
'active': 'volume-%s' % volume.id}
snap_info = {'active': 'volume-%s' % volume.id}
self._write_info_file(info_path, snap_info)
self._copy_volume_from_snapshot(temp_snapshot,
volume,
@ -599,10 +681,11 @@ class VZStorageDriver(remotefs_drv.RemoteFSSnapDriver):
return {'provider_location': src_vref.provider_location}
@remotefs_drv.locked_volume_id_operation
def create_cloned_volume(self, vol, src_vref):
def create_cloned_volume(self, volume, src_vref):
"""Creates a clone of the specified volume."""
volume_format = self.get_volume_format(src_vref)
if volume_format == 'parallels':
self._create_cloned_volume(vol, src_vref)
self._create_cloned_volume(volume, src_vref)
else:
super(VZStorageDriver, self)._create_cloned_volume(vol, src_vref)
super(VZStorageDriver, self)._create_cloned_volume(volume,
src_vref)