openstack/nova
Code Issues Proposed changes

libvirt: Use 'relative' flag for online snapshot's commit/rebase operations

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libvirt added support for _RELATIVE flag in v1.2.7 and when available this
flag _must_ be used to ensure backing paths are maintained relative during
snapshot delete operations.

This patch uses _RELATIVE flag if available, for both blockCommit and
blockRebase cases for both file and network backed disks.

If _RELATIVE flag is unavailable, it raises excp for blockCommit case
(since we can't get relative paths and Cinder flow is broken), but only
puts out a warning message for blockRebase case (since relative paths
works even for older libvirt)

Closes-Bug: 1438027
Change-Id: I9bda95cd4ab09aed88536d4a988d6c6579441c37
This commit is contained in:
Deepak C Shetty
2015-03-30 06:46:37 +00:00
parent e8707aa3b5
commit 7458c85daa
3 changed files with 211 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
nova/tests/unit/virt/libvirt/fakelibvirt.py
View File

@@ -133,6 +133,8 @@ VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE = 64
# blockCommit flags
VIR_DOMAIN_BLOCK_COMMIT_RELATIVE = 4
# blockRebase flags
VIR_DOMAIN_BLOCK_REBASE_RELATIVE = 8
VIR_CONNECT_LIST_DOMAINS_ACTIVE = 1

179
nova/tests/unit/virt/libvirt/test_driver.py
View File

@@ -13188,6 +13188,10 @@ class LibvirtVolumeSnapshotTestCase(test.NoDBTestCase):
def test_volume_snapshot_delete_1(self):
"""Deleting newest snapshot -- blockRebase."""
# libvirt lib doesn't have VIR_DOMAIN_BLOCK_REBASE_RELATIVE flag
fakelibvirt.__dict__.pop('VIR_DOMAIN_BLOCK_REBASE_RELATIVE')
self.stubs.Set(libvirt_driver, 'libvirt', fakelibvirt)
instance = objects.Instance(**self.inst)
snapshot_id = 'snapshot-1234'
@@ -13215,9 +13219,14 @@ class LibvirtVolumeSnapshotTestCase(test.NoDBTestCase):
snapshot_id, self.delete_info_1)
self.mox.VerifyAll()
fakelibvirt.__dict__.update({'VIR_DOMAIN_BLOCK_REBASE_RELATIVE': 8})
def test_volume_snapshot_delete_2(self):
"""Deleting older snapshot -- blockCommit."""
def test_volume_snapshot_delete_relative_1(self):
"""Deleting newest snapshot -- blockRebase using relative flag"""
# Ensure the libvirt lib has VIR_DOMAIN_BLOCK_REBASE_RELATIVE
fakelibvirt.__dict__.update({'VIR_DOMAIN_BLOCK_REBASE_RELATIVE': 8})
self.stubs.Set(libvirt_driver, 'libvirt', fakelibvirt)
instance = objects.Instance(**self.inst)
snapshot_id = 'snapshot-1234'
@@ -13235,7 +13244,80 @@ class LibvirtVolumeSnapshotTestCase(test.NoDBTestCase):
self.drvr._host.get_domain(instance).AndReturn(domain)
self.drvr._host.has_min_version(mox.IgnoreArg()).AndReturn(True)
domain.blockCommit('vda', 'other-snap.img', 'snap.img', 0, 0)
domain.blockRebase('vda', 'snap.img', 0,
fakelibvirt.VIR_DOMAIN_BLOCK_REBASE_RELATIVE)
domain.blockJobInfo('vda', 0).AndReturn({'cur': 1, 'end': 1000})
domain.blockJobInfo('vda', 0).AndReturn({'cur': 1000, 'end': 1000})
self.mox.ReplayAll()
self.drvr._volume_snapshot_delete(self.c, instance, self.volume_uuid,
snapshot_id, self.delete_info_1)
self.mox.VerifyAll()
fakelibvirt.__dict__.pop('VIR_DOMAIN_BLOCK_REBASE_RELATIVE')
def test_volume_snapshot_delete_2(self):
"""Deleting older snapshot -- blockCommit."""
# libvirt lib doesn't have VIR_DOMAIN_BLOCK_COMMIT_RELATIVE
fakelibvirt.__dict__.pop('VIR_DOMAIN_BLOCK_COMMIT_RELATIVE')
self.stubs.Set(libvirt_driver, 'libvirt', fakelibvirt)
instance = objects.Instance(**self.inst)
snapshot_id = 'snapshot-1234'
domain = FakeVirtDomain(fake_xml=self.dom_xml)
self.mox.StubOutWithMock(domain, 'XMLDesc')
domain.XMLDesc(0).AndReturn(self.dom_xml)
self.mox.StubOutWithMock(self.drvr._host, 'get_domain')
self.mox.StubOutWithMock(self.drvr._host, 'has_min_version')
self.mox.StubOutWithMock(domain, 'blockRebase')
self.mox.StubOutWithMock(domain, 'blockCommit')
self.mox.StubOutWithMock(domain, 'blockJobInfo')
self.drvr._host.get_domain(instance).AndReturn(domain)
self.drvr._host.has_min_version(mox.IgnoreArg()).AndReturn(True)
self.mox.ReplayAll()
self.assertRaises(exception.Invalid,
self.drvr._volume_snapshot_delete,
self.c,
instance,
self.volume_uuid,
snapshot_id,
self.delete_info_2)
fakelibvirt.__dict__.update({'VIR_DOMAIN_BLOCK_COMMIT_RELATIVE': 4})
def test_volume_snapshot_delete_relative_2(self):
"""Deleting older snapshot -- blockCommit using relative flag"""
# Ensure the libvirt lib has VIR_DOMAIN_BLOCK_COMMIT_RELATIVE
fakelibvirt.__dict__.update({'VIR_DOMAIN_BLOCK_COMMIT_RELATIVE': 4})
self.stubs.Set(libvirt_driver, 'libvirt', fakelibvirt)
instance = objects.Instance(**self.inst)
snapshot_id = 'snapshot-1234'
domain = FakeVirtDomain(fake_xml=self.dom_xml)
self.mox.StubOutWithMock(domain, 'XMLDesc')
domain.XMLDesc(0).AndReturn(self.dom_xml)
self.mox.StubOutWithMock(self.drvr._host, 'get_domain')
self.mox.StubOutWithMock(self.drvr._host, 'has_min_version')
self.mox.StubOutWithMock(domain, 'blockRebase')
self.mox.StubOutWithMock(domain, 'blockCommit')
self.mox.StubOutWithMock(domain, 'blockJobInfo')
self.drvr._host.get_domain(instance).AndReturn(domain)
self.drvr._host.has_min_version(mox.IgnoreArg()).AndReturn(True)
domain.blockCommit('vda', 'other-snap.img', 'snap.img', 0,
fakelibvirt.VIR_DOMAIN_BLOCK_COMMIT_RELATIVE)
domain.blockJobInfo('vda', 0).AndReturn({'cur': 1, 'end': 1000})
domain.blockJobInfo('vda', 0).AndReturn({})
@@ -13246,6 +13328,7 @@ class LibvirtVolumeSnapshotTestCase(test.NoDBTestCase):
snapshot_id, self.delete_info_2)
self.mox.VerifyAll()
fakelibvirt.__dict__.pop('VIR_DOMAIN_BLOCK_COMMIT_RELATIVE')
def test_volume_snapshot_delete_outer_success(self):
instance = objects.Instance(**self.inst)
@@ -13344,7 +13427,8 @@ class LibvirtVolumeSnapshotTestCase(test.NoDBTestCase):
def XMLDesc(self, *args):
return self.dom_netdisk_xml
# Ensure the libvirt lib has VIR_DOMAIN_BLOCK_COMMIT_RELATIVE
# libvirt lib doesn't have VIR_DOMAIN_BLOCK_REBASE_RELATIVE
fakelibvirt.__dict__.pop('VIR_DOMAIN_BLOCK_REBASE_RELATIVE')
self.stubs.Set(libvirt_driver, 'libvirt', fakelibvirt)
instance = objects.Instance(**self.inst)
@@ -13370,14 +13454,99 @@ class LibvirtVolumeSnapshotTestCase(test.NoDBTestCase):
self.mox.ReplayAll()
self.drvr._volume_snapshot_delete(self.c, instance, self.volume_uuid,
snapshot_id, self.delete_info_1)
self.mox.VerifyAll()
fakelibvirt.__dict__.update({'VIR_DOMAIN_BLOCK_REBASE_RELATIVE': 8})
def test_volume_snapshot_delete_netdisk_relative_1(self):
"""Delete newest snapshot -- blockRebase for libgfapi/network disk."""
class FakeNetdiskDomain(FakeVirtDomain):
def __init__(self, *args, **kwargs):
super(FakeNetdiskDomain, self).__init__(*args, **kwargs)
def XMLDesc(self, *args):
return self.dom_netdisk_xml
# Ensure the libvirt lib has VIR_DOMAIN_BLOCK_REBASE_RELATIVE
fakelibvirt.__dict__.update({'VIR_DOMAIN_BLOCK_REBASE_RELATIVE': 8})
self.stubs.Set(libvirt_driver, 'libvirt', fakelibvirt)
instance = objects.Instance(**self.inst)
snapshot_id = 'snapshot-1234'
domain = FakeNetdiskDomain(fake_xml=self.dom_netdisk_xml)
self.mox.StubOutWithMock(domain, 'XMLDesc')
domain.XMLDesc(0).AndReturn(self.dom_netdisk_xml)
self.mox.StubOutWithMock(self.drvr._host, 'get_domain')
self.mox.StubOutWithMock(self.drvr._host, 'has_min_version')
self.mox.StubOutWithMock(domain, 'blockRebase')
self.mox.StubOutWithMock(domain, 'blockCommit')
self.mox.StubOutWithMock(domain, 'blockJobInfo')
self.drvr._host.get_domain(instance).AndReturn(domain)
self.drvr._host.has_min_version(mox.IgnoreArg()).AndReturn(True)
domain.blockRebase('vdb', 'vdb[1]', 0,
fakelibvirt.VIR_DOMAIN_BLOCK_REBASE_RELATIVE)
domain.blockJobInfo('vdb', 0).AndReturn({'cur': 1, 'end': 1000})
domain.blockJobInfo('vdb', 0).AndReturn({'cur': 1000, 'end': 1000})
self.mox.ReplayAll()
self.drvr._volume_snapshot_delete(self.c, instance, self.volume_uuid,
snapshot_id, self.delete_info_1)
self.mox.VerifyAll()
fakelibvirt.__dict__.pop('VIR_DOMAIN_BLOCK_REBASE_RELATIVE')
def test_volume_snapshot_delete_netdisk_2(self):
"""Delete older snapshot -- blockCommit for libgfapi/network disk."""
class FakeNetdiskDomain(FakeVirtDomain):
def __init__(self, *args, **kwargs):
super(FakeNetdiskDomain, self).__init__(*args, **kwargs)
def XMLDesc(self, *args):
return self.dom_netdisk_xml
# libvirt lib doesn't have VIR_DOMAIN_BLOCK_COMMIT_RELATIVE
fakelibvirt.__dict__.pop('VIR_DOMAIN_BLOCK_COMMIT_RELATIVE')
self.stubs.Set(libvirt_driver, 'libvirt', fakelibvirt)
instance = objects.Instance(**self.inst)
snapshot_id = 'snapshot-1234'
domain = FakeNetdiskDomain(fake_xml=self.dom_netdisk_xml)
self.mox.StubOutWithMock(domain, 'XMLDesc')
domain.XMLDesc(0).AndReturn(self.dom_netdisk_xml)
self.mox.StubOutWithMock(self.drvr._host, 'get_domain')
self.mox.StubOutWithMock(self.drvr._host, 'has_min_version')
self.mox.StubOutWithMock(domain, 'blockRebase')
self.mox.StubOutWithMock(domain, 'blockCommit')
self.mox.StubOutWithMock(domain, 'blockJobInfo')
self.drvr._host.get_domain(instance).AndReturn(domain)
self.drvr._host.has_min_version(mox.IgnoreArg()).AndReturn(True)
self.mox.ReplayAll()
self.assertRaises(exception.Invalid,
self.drvr._volume_snapshot_delete,
self.c,
instance,
self.volume_uuid,
snapshot_id,
self.delete_info_netdisk)
fakelibvirt.__dict__.update({'VIR_DOMAIN_BLOCK_COMMIT_RELATIVE': 4})
def test_volume_snapshot_delete_netdisk_relative_2(self):
"""Delete older snapshot -- blockCommit for libgfapi/network disk."""
class FakeNetdiskDomain(FakeVirtDomain):
def __init__(self, *args, **kwargs):
super(FakeNetdiskDomain, self).__init__(*args, **kwargs)
@@ -13386,6 +13555,7 @@ class LibvirtVolumeSnapshotTestCase(test.NoDBTestCase):
return self.dom_netdisk_xml
# Ensure the libvirt lib has VIR_DOMAIN_BLOCK_COMMIT_RELATIVE
fakelibvirt.__dict__.update({'VIR_DOMAIN_BLOCK_COMMIT_RELATIVE': 4})
self.stubs.Set(libvirt_driver, 'libvirt', fakelibvirt)
instance = objects.Instance(**self.inst)
@@ -13417,6 +13587,7 @@ class LibvirtVolumeSnapshotTestCase(test.NoDBTestCase):
self.delete_info_netdisk)
self.mox.VerifyAll()
fakelibvirt.__dict__.pop('VIR_DOMAIN_BLOCK_COMMIT_RELATIVE')
def _fake_convert_image(source, dest, out_format,

47
nova/virt/libvirt/driver.py
View File

@@ -341,9 +341,9 @@ MIN_QEMU_LIVESNAPSHOT_VERSION = (1, 3, 0)
MIN_LIBVIRT_BLOCKIO_VERSION = (0, 10, 2)
# BlockJobInfo management requirement
MIN_LIBVIRT_BLOCKJOBINFO_VERSION = (1, 1, 1)
# Relative block commit (feature is detected,
# Relative block commit & rebase (feature is detected,
# this version is only used for messaging)
MIN_LIBVIRT_BLOCKCOMMIT_RELATIVE_VERSION = (1, 2, 7)
MIN_LIBVIRT_BLOCKJOB_RELATIVE_VERSION = (1, 2, 7)
# libvirt discard feature
MIN_LIBVIRT_DISCARD_VERSION = (1, 0, 6)
MIN_QEMU_DISCARD_VERSION = (1, 6, 0)
@@ -1883,6 +1883,19 @@ class LibvirtDriver(driver.ComputeDriver):
active_disk_object.backing_store)
rebase_bw = 0
# NOTE(deepakcs): libvirt added support for _RELATIVE in v1.2.7,
# and when available this flag _must_ be used to ensure backing
# paths are maintained relative by qemu.
#
# If _RELATIVE flag not found, continue with old behaviour
# (relative backing path seems to work for this case)
try:
if rebase_base is not None:
rebase_flags |= libvirt.VIR_DOMAIN_BLOCK_REBASE_RELATIVE
except AttributeError:
LOG.warn(_LW("Relative blockrebase support was not detected. "
"Continuing with old behaviour."))
LOG.debug('disk: %(disk)s, base: %(base)s, '
'bw: %(bw)s, flags: %(flags)s',
{'disk': rebase_disk,
@@ -1908,22 +1921,30 @@ class LibvirtDriver(driver.ComputeDriver):
commit_disk = my_dev
commit_flags = 0
# NOTE(deepakcs): libvirt added support for _RELATIVE in v1.2.7,
# and when available this flag _must_ be used to ensure backing
# paths are maintained relative by qemu.
#
# If _RELATIVE flag not found, raise exception as relative backing
# path may not be maintained and Cinder flow is broken if allowed
# to continue.
try:
commit_flags |= libvirt.VIR_DOMAIN_BLOCK_COMMIT_RELATIVE
except AttributeError:
ver = '.'.join(
[str(x) for x in
MIN_LIBVIRT_BLOCKJOB_RELATIVE_VERSION])
msg = _("Relative blockcommit support was not detected. "
"Libvirt '%s' or later is required for online "
"deletion of file/network storage-backed volume "
"snapshots.") % ver
raise exception.Invalid(msg)
if active_protocol is not None:
my_snap_base = _get_snap_dev(delete_info['merge_target_file'],
active_disk_object.backing_store)
my_snap_top = _get_snap_dev(delete_info['file_to_merge'],
active_disk_object.backing_store)
try:
commit_flags |= libvirt.VIR_DOMAIN_BLOCK_COMMIT_RELATIVE
except AttributeError:
ver = '.'.join(
[str(x) for x in
MIN_LIBVIRT_BLOCKCOMMIT_RELATIVE_VERSION])
msg = _("Relative blockcommit support was not detected. "
"Libvirt '%s' or later is required for online "
"deletion of network storage-backed volume "
"snapshots.") % ver
raise exception.Invalid(msg)
commit_base = my_snap_base or delete_info['merge_target_file']
commit_top = my_snap_top or delete_info['file_to_merge']