openstack
/
nova
Code Issues Proposed changes

Teardown container rootfs in host namespace for lxc 

Unlike other hypervisor to directly using image for VM, rootfs need to
be mounted in setup_container() for lxc before launching the domain.

However, this leads to several problems:

* previously spawned container polluted later spawned container, which
  in turn causing lvm device refused to be removed, as bug descirbes
* container rootfs not mounted after nova stop/start sequence

This commit addresses above two issues.

Fixes bug 1091639

Change-Id: I718baa6e46cf07a5458a5b80d42139dd353ae51c
This commit is contained in:
unicell 2012-12-24 18:08:56 +08:00
parent a52af4aee1
commit 5f697f64e5
4 changed files with 36 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
nova/tests/test_libvirt.py
View File

@ -4229,7 +4229,7 @@ class LibvirtDriverTestCase(test.TestCase):
block_device_info=None):
pass
def fake_create_domain(xml):
def fake_create_domain(xml, inst_name=''):
return None
def fake_enable_hairpin(instance):
@ -4275,7 +4275,7 @@ class LibvirtDriverTestCase(test.TestCase):
def fake_plug_vifs(instance, network_info):
pass
def fake_create_domain(xml):
def fake_create_domain(xml, inst_name=''):
return None
def fake_enable_hairpin(instance):

10
nova/tests/test_virt.py
View File

@ -95,7 +95,7 @@ class TestVirtDisk(test.TestCase):
self.stubs.Set(utils, 'execute', fake_execute)
def test_lxc_destroy_container(self):
def test_lxc_teardown_container(self):
def proc_mounts(self, mount_point):
mount_points = {
@ -110,26 +110,26 @@ class TestVirtDisk(test.TestCase):
self.stubs.Set(disk_api._DiskImage, '_device_for_path', proc_mounts)
expected_commands = []
disk_api.destroy_container('/mnt/loop/nopart')
disk_api.teardown_container('/mnt/loop/nopart')
expected_commands += [
('umount', '/dev/loop0'),
('losetup', '--detach', '/dev/loop0'),
]
disk_api.destroy_container('/mnt/loop/part')
disk_api.teardown_container('/mnt/loop/part')
expected_commands += [
('umount', '/dev/mapper/loop0p1'),
('kpartx', '-d', '/dev/loop0'),
('losetup', '--detach', '/dev/loop0'),
]
disk_api.destroy_container('/mnt/nbd/nopart')
disk_api.teardown_container('/mnt/nbd/nopart')
expected_commands += [
('umount', '/dev/nbd15'),
('qemu-nbd', '-d', '/dev/nbd15'),
]
disk_api.destroy_container('/mnt/nbd/part')
disk_api.teardown_container('/mnt/nbd/part')
expected_commands += [
('umount', '/dev/mapper/nbd15p1'),
('kpartx', '-d', '/dev/nbd15'),

6
nova/virt/disk/api.py
View File

@ -294,11 +294,11 @@ def setup_container(image, container_dir, use_cow=False):
raise exception.NovaException(img.errors)
def destroy_container(container_dir):
"""Destroy the container once it terminates.
def teardown_container(container_dir):
"""Teardown the container rootfs mounting once it is spawned.
It will umount the container that is mounted,
and delete any linked devices.
and delete any linked devices.
"""
try:
img = _DiskImage(image=None, mount_dir=container_dir)

46
nova/virt/libvirt/driver.py
View File

@ -577,11 +577,6 @@ class LibvirtDriver(driver.ComputeDriver):
target = os.path.join(CONF.instances_path, instance['name'])
LOG.info(_('Deleting instance files %(target)s') % locals(),
instance=instance)
if CONF.libvirt_type == 'lxc':
container_dir = os.path.join(CONF.instances_path,
instance['name'],
'rootfs')
disk.destroy_container(container_dir=container_dir)
if os.path.exists(target):
# If we fail to get rid of the directory
# tree, this shouldn't block deletion of
@ -949,7 +944,7 @@ class LibvirtDriver(driver.ComputeDriver):
power_state.CRASHED]:
LOG.info(_("Instance shutdown successfully."),
instance=instance)
self._create_domain(domain=dom)
self._create_domain(domain=dom, inst_name=instance['name'])
timer = utils.LoopingCall(self._wait_for_running, instance)
timer.start(interval=0.5).wait()
return True
@ -1011,7 +1006,7 @@ class LibvirtDriver(driver.ComputeDriver):
def power_on(self, instance):
"""Power on the specified instance"""
dom = self._lookup_by_name(instance['name'])
self._create_domain(domain=dom)
self._create_domain(domain=dom, inst_name=instance['name'])
timer = utils.LoopingCall(self._wait_for_running, instance)
timer.start(interval=0.5).wait()
@ -1317,12 +1312,6 @@ class LibvirtDriver(driver.ComputeDriver):
LOG.info(_('Creating image'), instance=instance)
libvirt_utils.write_to_file(basepath('libvirt.xml'), libvirt_xml)
if CONF.libvirt_type == 'lxc':
container_dir = os.path.join(CONF.instances_path,
instance['name'],
'rootfs')
fileutils.ensure_tree(container_dir)
# NOTE(dprince): for rescue console.log may already exist... chown it.
self._chown_console_log_for_instance(instance['name'])
@ -1484,11 +1473,6 @@ class LibvirtDriver(driver.ComputeDriver):
'%(img_id)s (%(e)s)') % locals(),
instance=instance)
if CONF.libvirt_type == 'lxc':
disk.setup_container(image('disk').path,
container_dir=container_dir,
use_cow=CONF.use_cow_images)
if CONF.libvirt_type == 'uml':
libvirt_utils.chown(image('disk').path, 'root')
@ -1947,16 +1931,37 @@ class LibvirtDriver(driver.ComputeDriver):
'num_cpu': num_cpu,
'cpu_time': cpu_time}
def _create_domain(self, xml=None, domain=None, launch_flags=0):
def _create_domain(self, xml=None, domain=None,
inst_name='', launch_flags=0):
"""Create a domain.
Either domain or xml must be passed in. If both are passed, then
the domain definition is overwritten from the xml.
"""
if CONF.libvirt_type == 'lxc':
container_dir = os.path.join(CONF.instances_path,
inst_name,
'rootfs')
fileutils.ensure_tree(container_dir)
image = self.image_backend.image(inst_name, 'disk')
disk.setup_container(image.path,
container_dir=container_dir,
use_cow=CONF.use_cow_images)
if xml:
domain = self._conn.defineXML(xml)
domain.createWithFlags(launch_flags)
self._enable_hairpin(domain.XMLDesc(0))
# NOTE(uni): Now the container is running with its own private mount
# namespace and so there is no need to keep the container rootfs
# mounted in the host namespace
if CONF.libvirt_type == 'lxc':
container_dir = os.path.join(CONF.instances_path,
inst_name,
'rootfs')
disk.teardown_container(container_dir=container_dir)
return domain
def _create_domain_and_network(self, xml, instance, network_info,
@ -1976,7 +1981,8 @@ class LibvirtDriver(driver.ComputeDriver):
self.plug_vifs(instance, network_info)
self.firewall_driver.setup_basic_filtering(instance, network_info)
self.firewall_driver.prepare_instance_filter(instance, network_info)
domain = self._create_domain(xml)
domain = self._create_domain(xml, inst_name=instance['name'])
self.firewall_driver.apply_instance_filter(instance, network_info)
return domain