openstack/nova
Code Issues Proposed changes

xenapi: remove pv detection

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It was assumed that pygrub is there in domU, so that the RAW and unknown
disks were attached to domU and investigated with pygrub to find out if
PV could be used. This patch removes this functionality. Also some
cleanup is made around the ImageType mess.

From now RAW and unknown disks will not be investigated for PV-ness and
will boot as HVM.

Fixes bug 1196570

Change-Id: If84b93cee36938257b7ad0fa44b3b22878520506
This commit is contained in:
Mate Lakat 2013-07-10 18:51:17 +01:00
parent 6a3f5fd6cc
commit e3ef5214c6
3 changed files with 24 additions and 69 deletions
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6
nova/tests/virt/xenapi/stubs.py
View File

@ -83,12 +83,6 @@ def stubout_stream_disk(stubs):
stubs.Set(vm_utils, '_stream_disk', fake_stream_disk)
def stubout_is_vdi_pv(stubs):
def f(_1):
return False
stubs.Set(vm_utils, '_is_vdi_pv', f)
def stubout_determine_is_pv_objectstore(stubs):
"""Assumes VMs stu have PV kernels."""

18
nova/tests/virt/xenapi/test_xenapi.py
View File

@ -147,7 +147,7 @@ def get_fake_device_info():
return fake
def stub_vm_utils_with_vdi_attached_here(function, should_return=True):
def stub_vm_utils_with_vdi_attached_here(function):
"""
vm_utils.with_vdi_attached_here needs to be stubbed out because it
calls down to the filesystem to attach a vdi. This provides a
@ -163,19 +163,13 @@ def stub_vm_utils_with_vdi_attached_here(function, should_return=True):
def fake_image_download(*args, **kwargs):
pass
def fake_is_vdi_pv(*args, **kwargs):
return should_return
orig_vdi_attached_here = vm_utils.vdi_attached_here
orig_image_download = fake_image._FakeImageService.download
orig_is_vdi_pv = vm_utils._is_vdi_pv
try:
vm_utils.vdi_attached_here = fake_vdi_attached_here
fake_image._FakeImageService.download = fake_image_download
vm_utils._is_vdi_pv = fake_is_vdi_pv
return function(self, *args, **kwargs)
finally:
vm_utils._is_vdi_pv = orig_is_vdi_pv
fake_image._FakeImageService.download = orig_image_download
vm_utils.vdi_attached_here = orig_vdi_attached_here
@ -328,7 +322,6 @@ class XenAPIVMTestCase(stubs.XenAPITestBase):
xenapi_fake.create_network('fake', CONF.flat_network_bridge)
stubs.stubout_session(self.stubs, stubs.FakeSessionForVMTests)
stubs.stubout_get_this_vm_uuid(self.stubs)
stubs.stubout_is_vdi_pv(self.stubs)
stubs.stub_out_vm_methods(self.stubs)
fake_processutils.stub_out_processutils_execute(self.stubs)
self.user_id = 'fake'
@ -810,10 +803,9 @@ class XenAPIVMTestCase(stubs.XenAPITestBase):
# No additional VMs should be found.
self.assertEqual(start_vms, end_vms)
@stub_vm_utils_with_vdi_attached_here
def test_spawn_raw_glance(self):
self._test_spawn(IMAGE_RAW, None, None)
self.check_vm_params_for_linux()
self.check_vm_params_for_windows()
def test_spawn_vhd_glance_linux(self):
self._test_spawn(IMAGE_VHD, None, None,
@ -1886,9 +1878,8 @@ class XenAPIDetermineIsPVTestCase(test.TestCase):
def test_linux_vhd(self):
self.assert_pv_status(vm_utils.ImageType.DISK_VHD, 'linux', True)
@stub_vm_utils_with_vdi_attached_here
def test_raw(self):
self.assert_pv_status(vm_utils.ImageType.DISK_RAW, 'linux', True)
self.assert_pv_status(vm_utils.ImageType.DISK_RAW, 'linux', False)
def test_disk(self):
self.assert_pv_status(vm_utils.ImageType.DISK, None, True)
@ -1896,9 +1887,8 @@ class XenAPIDetermineIsPVTestCase(test.TestCase):
def test_iso(self):
self.assert_pv_status(vm_utils.ImageType.DISK_ISO, None, False)
@stub_vm_utils_with_vdi_attached_here
def test_none(self):
self.assert_pv_status(None, None, True)
self.assert_pv_status(None, None, False)
class CompareVersionTestCase(test.TestCase):

69
nova/virt/xenapi/vm_utils.py
View File

@ -1436,24 +1436,27 @@ def determine_disk_image_type(image_meta):
disk_format = image_meta['disk_format']
disk_format_map = {
'ami': 'DISK',
'aki': 'KERNEL',
'ari': 'RAMDISK',
'raw': 'DISK_RAW',
'vhd': 'DISK_VHD',
'iso': 'DISK_ISO',
'ami': ImageType.DISK,
'aki': ImageType.KERNEL,
'ari': ImageType.RAMDISK,
'raw': ImageType.DISK_RAW,
'vhd': ImageType.DISK_VHD,
'iso': ImageType.DISK_ISO,
}
try:
image_type_str = disk_format_map[disk_format]
image_type = disk_format_map[disk_format]
except KeyError:
raise exception.InvalidDiskFormat(disk_format=disk_format)
image_type = getattr(ImageType, image_type_str)
image_ref = image_meta['id']
params = {
'image_type_str': ImageType.to_string(image_type),
'image_ref': image_ref
}
LOG.debug(_("Detected %(image_type_str)s format for image %(image_ref)s"),
{'image_type_str': image_type_str, 'image_ref': image_ref})
params)
return image_type
@ -1463,21 +1466,15 @@ def determine_is_pv(session, vdi_ref, disk_image_type, os_type):
Determine whether the VM will use a paravirtualized kernel or if it
will use hardware virtualization.
1. Glance (VHD): then we use `os_type`, raise if not set
1. Glance (VHD): if `os_type` is windows, HVM, otherwise PV
2. Glance (DISK_RAW): use Pygrub to figure out if pv kernel is
available
2. Glance (DISK_RAW): HVM
3. Glance (DISK): pv is assumed
3. Glance (DISK): PV
4. Glance (DISK_ISO): no pv is assumed
4. Glance (DISK_ISO): HVM
5. Boot From Volume - without image metadata (None): attempt to
use Pygrub to figure out if the volume stores a PV VM or a
HVM one. Log a warning, because there may be cases where the
volume is RAW (in which case using pygrub is fine) and cases
where the content of the volume is VHD, and pygrub might not
work as expected.
5. Boot From Volume - without image metadata (None): use HVM
NOTE: if disk_image_type is not specified, instances launched
from remote volumes will have to include kernel and ramdisk
because external kernel and ramdisk will not be fetched.
@ -1492,8 +1489,7 @@ def determine_is_pv(session, vdi_ref, disk_image_type, os_type):
is_pv = True
elif disk_image_type == ImageType.DISK_RAW:
# 2. RAW
with vdi_attached_here(session, vdi_ref, read_only=True) as dev:
is_pv = _is_vdi_pv(dev)
is_pv = False
elif disk_image_type == ImageType.DISK:
# 3. Disk
is_pv = True
@ -1501,11 +1497,7 @@ def determine_is_pv(session, vdi_ref, disk_image_type, os_type):
# 4. ISO
is_pv = False
elif not disk_image_type:
LOG.warning(_("Image format is None: trying to determine PV status "
"using pygrub; if instance with vdi %s does not boot "
"correctly, try with image metadata.") % vdi_ref)
with vdi_attached_here(session, vdi_ref, read_only=True) as dev:
is_pv = _is_vdi_pv(dev)
is_pv = False
else:
raise exception.NovaException(_("Unknown image format %s") %
disk_image_type)
@ -2018,27 +2010,6 @@ def _get_this_vm_ref(session):
return session.call_xenapi("VM.get_by_uuid", get_this_vm_uuid())
def _is_vdi_pv(dev):
LOG.debug(_("Running pygrub against %s"), dev)
dev_path = utils.make_dev_path(dev)
try:
out, err = utils.execute('pygrub', '-qn', dev_path, run_as_root=True)
for line in out:
# try to find kernel string
m = re.search('(?<=kernel:)/.*(?:>)', line)
if m and m.group(0).find('xen') != -1:
LOG.debug(_("Found Xen kernel %s") % m.group(0))
return True
LOG.debug(_("No Xen kernel found. Booting HVM."))
except processutils.ProcessExecutionError:
LOG.exception(_("Error while executing pygrub! Please, ensure the "
"binary is installed correctly, and available in your "
"PATH; on some Linux distros, pygrub may be installed "
"in /usr/lib/xen-X.Y/bin/pygrub. Attempting to boot "
"in HVM mode."))
return False
def _get_partitions(dev):
"""Return partition information (num, size, type) for a device."""
dev_path = utils.make_dev_path(dev)