def verify_base_size(self, base, size, base_size=0):
"""Check that the base image is not larger than size.
Since images can't be generally shrunk, enforce this
constraint taking account of virtual image size.
"""
# Note(pbrady): The size and min_disk parameters of a glance
# image are checked against the instance size before the image
# is even downloaded from glance, but currently min_disk is
# adjustable and doesn't currently account for virtual disk size,
# so we need this extra check here.
# NOTE(cfb): Having a flavor that sets the root size to 0 and having
# nova effectively ignore that size and use the size of the
# image is considered a feature at this time, not a bug.
if size is None:
return
if size and not base_size:
base_size = self.get_disk_size(base)
if size < base_size:
msg = _LE('%(base)s virtual size %(base_size)s '
'larger than flavor root disk size %(size)s')
LOG.error(msg % {
'base': base,
'base_size': base_size,
'size': size
})
raise exception.FlavorDiskSmallerThanImage(flavor_size=size,
image_size=base_size)
def fetch_to_raw(context, image_href, path, max_size=0):
path_tmp = "%s.part" % path
fetch(context, image_href, path_tmp, max_size=max_size)
with fileutils.remove_path_on_error(path_tmp):
data = qemu_img_info(path_tmp)
fmt = data.file_format
if fmt is None:
raise exception.ImageUnacceptable(
reason=_("'qemu-img info' parsing failed."),
image_id=image_href)
backing_file = data.backing_file
if backing_file is not None:
raise exception.ImageUnacceptable(image_id=image_href,
reason=(_("fmt=%(fmt)s backed by: %(backing_file)s") %
{'fmt': fmt, 'backing_file': backing_file}))
# We can't generally shrink incoming images, so disallow
# images > size of the flavor we're booting. Checking here avoids
# an immediate DoS where we convert large qcow images to raw
# (which may compress well but not be sparse).
# TODO(p-draigbrady): loop through all flavor sizes, so that
# we might continue here and not discard the download.
# If we did that we'd have to do the higher level size checks
# irrespective of whether the base image was prepared or not.
disk_size = data.virtual_size
if max_size and max_size < disk_size:
LOG.error(_LE('%(base)s virtual size %(disk_size)s '
'larger than flavor root disk size %(size)s'),
{'base': path,
'disk_size': disk_size,
'size': max_size})
raise exception.FlavorDiskSmallerThanImage(
flavor_size=max_size, image_size=disk_size)
if fmt != "raw" and CONF.force_raw_images:
staged = "%s.converted" % path
LOG.debug("%s was %s, converting to raw", image_href, fmt)
with fileutils.remove_path_on_error(staged):
try:
convert_image(path_tmp, staged, fmt, 'raw')
except exception.ImageUnacceptable as exp:
# re-raise to include image_href
raise exception.ImageUnacceptable(image_id=image_href,
reason=_("Unable to convert image to raw: %(exp)s")
% {'exp': exp})
os.unlink(path_tmp)
data = qemu_img_info(staged)
if data.file_format != "raw":
raise exception.ImageUnacceptable(image_id=image_href,
reason=_("Converted to raw, but format is now %s") %
data.file_format)
os.rename(staged, path)
else:
os.rename(path_tmp, path)
def _is_resize_needed(self, vhd_path, old_size, new_size, instance):
if new_size < old_size:
raise exception.FlavorDiskSmallerThanImage(
flavor_size=new_size, image_size=old_size)
elif new_size > old_size:
LOG.debug("Resizing VHD %(vhd_path)s to new "
"size %(new_size)s" %
{'new_size': new_size,
'vhd_path': vhd_path},
instance=instance)
return True
return False
def _resize_and_cache_vhd(self, instance, vhd_path):
vhd_size = self._vhdutils.get_vhd_size(vhd_path)['VirtualSize']
root_vhd_size_gb = self._get_root_vhd_size_gb(instance)
root_vhd_size = root_vhd_size_gb * units.Gi
root_vhd_internal_size = (
self._vhdutils.get_internal_vhd_size_by_file_size(
vhd_path, root_vhd_size))
if root_vhd_internal_size < vhd_size:
raise exception.FlavorDiskSmallerThanImage(
flavor_size=root_vhd_size, image_size=vhd_size)
if root_vhd_internal_size > vhd_size:
path_parts = os.path.splitext(vhd_path)
resized_vhd_path = '%s_%s%s' % (path_parts[0], root_vhd_size_gb,
path_parts[1])
lock_path = os.path.dirname(resized_vhd_path)
lock_name = "%s-cache.lock" % os.path.basename(resized_vhd_path)
@utils.synchronized(name=lock_name,
external=True,
lock_path=lock_path)
def copy_and_resize_vhd():
if not self._pathutils.exists(resized_vhd_path):
try:
LOG.debug(
"Copying VHD %(vhd_path)s to "
"%(resized_vhd_path)s", {
'vhd_path': vhd_path,
'resized_vhd_path': resized_vhd_path
})
self._pathutils.copyfile(vhd_path, resized_vhd_path)
LOG.debug(
"Resizing VHD %(resized_vhd_path)s to new "
"size %(root_vhd_size)s", {
'resized_vhd_path': resized_vhd_path,
'root_vhd_size': root_vhd_size
})
self._vhdutils.resize_vhd(resized_vhd_path,
root_vhd_internal_size,
is_file_max_size=False)
except Exception:
with excutils.save_and_reraise_exception():
if self._pathutils.exists(resized_vhd_path):
self._pathutils.remove(resized_vhd_path)
copy_and_resize_vhd()
return resized_vhd_path
def _verify_rescue_image(self, instance, rescue_image_id,
rescue_image_path):
rescue_image_info = self._vhdutils.get_vhd_info(rescue_image_path)
rescue_image_size = rescue_image_info['VirtualSize']
flavor_disk_size = instance.root_gb * units.Gi
if rescue_image_size > flavor_disk_size:
err_msg = _('Using a rescue image bigger than the instance '
'flavor disk size is not allowed. '
'Rescue image size: %(rescue_image_size)s. '
'Flavor disk size:%(flavor_disk_size)s. '
'Rescue image id %(rescue_image_id)s.')
raise exception.FlavorDiskSmallerThanImage(err_msg %
{'rescue_image_size': rescue_image_size,
'flavor_disk_size': flavor_disk_size,
'rescue_image_id': rescue_image_id})
