virt-manager/virtinst/storage.py
Pavel Hrdina 26a433fc42 virtManager: clone: check which storage pools supports volume cloning
When cloning a guest in virt-manager the GUI shows a list of disks and
select default cloning policy for every disk.  For storage pools where
we know that cloning is not possible we should not select that option
as default one.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1463066

Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2019-03-04 13:23:45 +01:00

828 lines
27 KiB
Python

#
# Copyright 2008, 2013, 2015 Red Hat, Inc.
#
# This work is licensed under the GNU GPLv2 or later.
# See the COPYING file in the top-level directory.
import os
import logging
import threading
import libvirt
from .xmlbuilder import XMLBuilder, XMLChildProperty, XMLProperty
from . import util
_DEFAULT_DEV_TARGET = "/dev"
_DEFAULT_LVM_TARGET_BASE = "/dev/"
_DEFAULT_SCSI_TARGET = "/dev/disk/by-path"
_DEFAULT_MPATH_TARGET = "/dev/mapper"
class _StoragePermissions(XMLBuilder):
XML_NAME = "permissions"
_XML_PROP_ORDER = ["mode", "owner", "group", "label"]
mode = XMLProperty("./mode")
owner = XMLProperty("./owner")
group = XMLProperty("./group")
label = XMLProperty("./label")
class _StorageObject(XMLBuilder):
"""
Base class for building any libvirt storage object.
Meaningless to directly instantiate.
"""
##############
# Properties #
##############
name = XMLProperty("./name")
permissions = XMLChildProperty(_StoragePermissions,
relative_xpath="./target",
is_single=True)
def _get_default_pool_path(conn):
path = "/var/lib/libvirt/images"
if conn.is_session_uri():
path = os.path.expanduser("~/.local/share/libvirt/images")
return path
class _EnumerateSource(XMLBuilder):
XML_NAME = "source"
class _EnumerateSources(XMLBuilder):
XML_NAME = "sources"
sources = XMLChildProperty(_EnumerateSource)
class _Host(XMLBuilder):
_XML_PROP_ORDER = ["name", "port"]
XML_NAME = "host"
name = XMLProperty("./@name")
port = XMLProperty("./@port", is_int=True)
class StoragePool(_StorageObject):
"""
Base class for building and installing libvirt storage pool xml
"""
# @group Types: TYPE_*
TYPE_DIR = "dir"
TYPE_FS = "fs"
TYPE_NETFS = "netfs"
TYPE_LOGICAL = "logical"
TYPE_DISK = "disk"
TYPE_ISCSI = "iscsi"
TYPE_SCSI = "scsi"
TYPE_MPATH = "mpath"
TYPE_GLUSTER = "gluster"
TYPE_RBD = "rbd"
TYPE_SHEEPDOG = "sheepdog"
TYPE_ZFS = "zfs"
# Pool type descriptions for use in higher level programs
_descs = {}
_descs[TYPE_DIR] = _("Filesystem Directory")
_descs[TYPE_FS] = _("Pre-Formatted Block Device")
_descs[TYPE_NETFS] = _("Network Exported Directory")
_descs[TYPE_LOGICAL] = _("LVM Volume Group")
_descs[TYPE_DISK] = _("Physical Disk Device")
_descs[TYPE_ISCSI] = _("iSCSI Target")
_descs[TYPE_SCSI] = _("SCSI Host Adapter")
_descs[TYPE_MPATH] = _("Multipath Device Enumerator")
_descs[TYPE_GLUSTER] = _("Gluster Filesystem")
_descs[TYPE_RBD] = _("RADOS Block Device/Ceph")
_descs[TYPE_SHEEPDOG] = _("Sheepdog Filesystem")
_descs[TYPE_ZFS] = _("ZFS Pool")
@staticmethod
def get_pool_types():
"""
Return list of appropriate pool types
"""
return list(StoragePool._descs.keys())
@staticmethod
def get_pool_type_desc(pool_type):
"""
Return human readable description for passed pool type
"""
return StoragePool._descs.get(pool_type, "%s pool" % pool_type)
@staticmethod
def pool_list_from_sources(conn, pool_type, host=None):
"""
Return a list of StoragePool instances built from libvirt's pool
source enumeration (if supported).
:param conn: Libvirt connection
:param name: Name for the new pool
:param pool_type: Pool type string from I{Types}
:param host: Option host string to poll for sources
"""
if host:
source_xml = "<source><host name='%s'/></source>" % host
else:
source_xml = "<source/>"
try:
xml = conn.findStoragePoolSources(pool_type, source_xml, 0)
except libvirt.libvirtError as e:
if util.is_error_nosupport(e):
return []
raise
ret = []
sources = _EnumerateSources(conn, xml)
for source in sources.sources:
source_xml = source.get_xml()
pool_xml = "<pool>\n%s\n</pool>" % (
util.xml_indent(source_xml, 2))
parseobj = StoragePool(conn, parsexml=pool_xml)
parseobj.type = pool_type
obj = StoragePool(conn)
obj.type = pool_type
obj.source_path = parseobj.source_path
for h in parseobj.hosts:
parseobj.remove_child(h)
obj.add_child(h)
obj.source_name = parseobj.source_name
obj.format = parseobj.format
ret.append(obj)
return ret
@staticmethod
def build_default_pool(conn):
"""
Helper to build the 'default' storage pool
"""
if not conn.check_support(conn.SUPPORT_CONN_STORAGE):
return
pool = None
name = "default"
path = _get_default_pool_path(conn)
if conn.is_session_uri() and not os.path.exists(path):
os.makedirs(path)
try:
pool = conn.storagePoolLookupByName(name)
except libvirt.libvirtError:
# Try default pool path when "default" name fails
pool = StoragePool.lookup_pool_by_path(conn, path)
if pool:
# This is a libvirt pool object so create a StoragePool from it
return StoragePool(conn, parsexml=pool.XMLDesc(0))
try:
logging.debug("Attempting to build default pool with target '%s'",
path)
defpool = StoragePool(conn)
defpool.type = defpool.TYPE_DIR
defpool.name = name
defpool.target_path = path
defpool.install(build=True, create=True, autostart=True)
return defpool
except Exception as e:
raise RuntimeError(
_("Couldn't create default storage pool '%s': %s") %
(path, str(e)))
@staticmethod
def get_default_dir(conn, build=False):
"""
Return the default storage dir. If there's a 'default' pool,
report that. If there's no default pool, return the dir we would
use for the default.
"""
path = _get_default_pool_path(conn)
if (not conn.is_remote() and
not conn.check_support(conn.SUPPORT_CONN_STORAGE)):
if build and not os.path.exists(path):
os.makedirs(path)
return path
try:
for pool in conn.fetch_all_pools():
if pool.name == "default":
return pool.target_path
except Exception:
pass
if build:
return StoragePool.build_default_pool(conn).target_path
return _get_default_pool_path(conn)
@staticmethod
def lookup_pool_by_path(conn, path):
"""
Return the first pool with matching matching target path.
return the first we find, active or inactive. This iterates over
all pools and dumps their xml, so it is NOT quick.
:returns: virStoragePool object if found, None otherwise
"""
if not conn.check_support(conn.SUPPORT_CONN_STORAGE):
return None
for pool in conn.fetch_all_pools():
xml_path = pool.target_path
if xml_path is not None and os.path.abspath(xml_path) == path:
return conn.storagePoolLookupByName(pool.name)
return None
@staticmethod
def find_free_name(conn, basename, **kwargs):
"""
Finds a name similar (or equal) to passed 'basename' that is not
in use by another pool. Extra params are passed to generate_name
"""
def cb(name):
for pool in conn.fetch_all_pools():
if pool.name == name:
return True
return False
kwargs["lib_collision"] = False
return util.generate_name(basename, cb, **kwargs)
######################
# Validation helpers #
######################
@staticmethod
def validate_name(conn, name):
util.validate_name(_("Storage object"), name)
try:
conn.storagePoolLookupByName(name)
except libvirt.libvirtError:
return
raise ValueError(_("Name '%s' already in use by another pool." %
name))
def default_target_path(self):
if not self.supports_property("target_path"):
return None
if (self.type == self.TYPE_DIR or
self.type == self.TYPE_NETFS or
self.type == self.TYPE_FS):
return os.path.join(self.get_default_dir(self.conn), self.name)
if self.type == self.TYPE_LOGICAL:
name = self.name
if self.source_name:
name = self.source_name
return _DEFAULT_LVM_TARGET_BASE + name
if self.type == self.TYPE_DISK:
return _DEFAULT_DEV_TARGET
if self.type == self.TYPE_ISCSI or self.type == self.TYPE_SCSI:
return _DEFAULT_SCSI_TARGET
if self.type == self.TYPE_MPATH:
return _DEFAULT_MPATH_TARGET
raise RuntimeError("No default target_path for type=%s" % self.type)
def _type_to_source_prop(self):
if (self.type == self.TYPE_NETFS or
self.type == self.TYPE_GLUSTER):
return "_source_dir"
elif self.type == self.TYPE_SCSI:
return "_source_adapter"
else:
return "_source_device"
def _get_source(self):
return getattr(self, self._type_to_source_prop())
def _set_source(self, val):
return setattr(self, self._type_to_source_prop(), val)
source_path = property(_get_source, _set_source)
def default_source_name(self):
srcname = None
if not self.supports_property("source_name"):
srcname = None
elif self.type == StoragePool.TYPE_NETFS:
srcname = self.name
elif self.type == StoragePool.TYPE_RBD:
srcname = "rbd"
elif self.type == StoragePool.TYPE_GLUSTER:
srcname = "gv0"
elif ("target_path" in self._propstore and
self.target_path and
self.target_path.startswith(_DEFAULT_LVM_TARGET_BASE)):
# If there is a target path, parse it for an expected VG
# location, and pull the name from there
vg = self.target_path[len(_DEFAULT_LVM_TARGET_BASE):]
srcname = vg.split("/", 1)[0]
return srcname
##############
# Properties #
##############
XML_NAME = "pool"
_XML_PROP_ORDER = ["name", "type", "uuid",
"capacity", "allocation", "available",
"format", "hosts",
"_source_dir", "_source_adapter", "_source_device",
"source_name", "target_path",
"permissions",
"auth_type", "auth_username", "auth_secret_uuid"]
_source_dir = XMLProperty("./source/dir/@path")
_source_adapter = XMLProperty("./source/adapter/@name")
_source_device = XMLProperty("./source/device/@path")
type = XMLProperty("./@type")
uuid = XMLProperty("./uuid")
capacity = XMLProperty("./capacity", is_int=True)
allocation = XMLProperty("./allocation", is_int=True)
available = XMLProperty("./available", is_int=True)
format = XMLProperty("./source/format/@type")
iqn = XMLProperty("./source/initiator/iqn/@name")
source_name = XMLProperty("./source/name")
auth_type = XMLProperty("./source/auth/@type")
auth_username = XMLProperty("./source/auth/@username")
auth_secret_uuid = XMLProperty("./source/auth/secret/@uuid")
target_path = XMLProperty("./target/path")
hosts = XMLChildProperty(_Host, relative_xpath="./source")
######################
# Public API helpers #
######################
def supports_property(self, propname):
users = {
"source_path": [self.TYPE_FS, self.TYPE_NETFS, self.TYPE_LOGICAL,
self.TYPE_DISK, self.TYPE_ISCSI, self.TYPE_SCSI,
self.TYPE_GLUSTER],
"source_name": [self.TYPE_LOGICAL, self.TYPE_GLUSTER,
self.TYPE_RBD, self.TYPE_SHEEPDOG, self.TYPE_ZFS],
"hosts": [self.TYPE_NETFS, self.TYPE_ISCSI, self.TYPE_GLUSTER,
self.TYPE_RBD, self.TYPE_SHEEPDOG],
"format": [self.TYPE_FS, self.TYPE_NETFS, self.TYPE_DISK],
"iqn": [self.TYPE_ISCSI],
"target_path": [self.TYPE_DIR, self.TYPE_FS, self.TYPE_NETFS,
self.TYPE_LOGICAL, self.TYPE_DISK, self.TYPE_ISCSI,
self.TYPE_SCSI, self.TYPE_MPATH]
}
if users.get(propname):
return self.type in users[propname]
return hasattr(self, propname)
def supports_volume_creation(self, clone=False):
"""
Returns if pool supports volume creation. If @clone is set to True
returns if pool supports volume cloning (virVolCreateXMLFrom).
"""
supported = [
StoragePool.TYPE_DIR,
StoragePool.TYPE_FS,
StoragePool.TYPE_NETFS,
StoragePool.TYPE_DISK,
StoragePool.TYPE_LOGICAL,
StoragePool.TYPE_RBD,
]
if not clone:
supported.extend([
StoragePool.TYPE_SHEEPDOG,
StoragePool.TYPE_ZFS,
])
return self.type in supported
def get_disk_type(self):
if (self.type == StoragePool.TYPE_DISK or
self.type == StoragePool.TYPE_LOGICAL or
self.type == StoragePool.TYPE_SCSI or
self.type == StoragePool.TYPE_MPATH or
self.type == StoragePool.TYPE_ZFS):
return StorageVolume.TYPE_BLOCK
if (self.type == StoragePool.TYPE_GLUSTER or
self.type == StoragePool.TYPE_RBD or
self.type == StoragePool.TYPE_ISCSI or
self.type == StoragePool.TYPE_SHEEPDOG):
return StorageVolume.TYPE_NETWORK
return StorageVolume.TYPE_FILE
##################
# Build routines #
##################
def validate(self):
self.validate_name(self.conn, self.name)
if not self.target_path:
self.target_path = self.default_target_path()
if not self.source_name:
self.source_name = self.default_source_name()
if not self.format and self.supports_property("format"):
self.format = "auto"
if self.supports_property("hosts") and not self.hosts:
raise RuntimeError(_("Hostname is required"))
if (self.supports_property("source_path") and
self.type != self.TYPE_LOGICAL and
not self.source_path):
raise RuntimeError(_("Source path is required"))
if (self.type == self.TYPE_DISK and self.format == "auto"):
# There is no explicit "auto" type for disk pools, but leaving out
# the format type seems to do the job for existing formatted disks
self.format = None
def install(self, meter=None, create=False, build=False, autostart=False):
"""
Install storage pool xml.
"""
if (self.type == self.TYPE_LOGICAL and
build and not self.source_path):
raise ValueError(_("Must explicitly specify source path if "
"building pool"))
if (self.type == self.TYPE_DISK and
build and self.format == "auto"):
raise ValueError(_("Must explicitly specify disk format if "
"formatting disk device."))
xml = self.get_xml()
logging.debug("Creating storage pool '%s' with xml:\n%s",
self.name, xml)
meter = util.ensure_meter(meter)
try:
pool = self.conn.storagePoolDefineXML(xml, 0)
except Exception as e:
raise RuntimeError(_("Could not define storage pool: %s") % str(e))
errmsg = None
if build:
try:
pool.build(libvirt.VIR_STORAGE_POOL_BUILD_NEW)
except Exception as e:
errmsg = _("Could not build storage pool: %s") % str(e)
if create and not errmsg:
try:
pool.create(0)
except Exception as e:
errmsg = _("Could not start storage pool: %s") % str(e)
if autostart and not errmsg:
try:
pool.setAutostart(True)
except Exception as e:
errmsg = _("Could not set pool autostart flag: %s") % str(e)
if errmsg:
# Try and clean up the leftover pool
try:
pool.undefine()
except Exception as e:
logging.debug("Error cleaning up pool after failure: %s",
str(e))
raise RuntimeError(errmsg)
self.conn.cache_new_pool(pool)
return pool
class StorageVolume(_StorageObject):
"""
Base class for building and installing libvirt storage volume xml
"""
@staticmethod
def get_file_extension_for_format(fmt):
if not fmt:
return ""
if fmt == "raw":
return ".img"
return "." + fmt
@staticmethod
def find_free_name(pool_object, basename, **kwargs):
"""
Finds a name similar (or equal) to passed 'basename' that is not
in use by another volume. Extra params are passed to generate_name
"""
pool_object.refresh(0)
return util.generate_name(basename,
pool_object.storageVolLookupByName,
**kwargs)
TYPE_FILE = getattr(libvirt, "VIR_STORAGE_VOL_FILE", 0)
TYPE_BLOCK = getattr(libvirt, "VIR_STORAGE_VOL_BLOCK", 1)
TYPE_DIR = getattr(libvirt, "VIR_STORAGE_VOL_DIR", 2)
TYPE_NETWORK = getattr(libvirt, "VIR_STORAGE_VOL_NETWORK", 3)
TYPE_NETDIR = getattr(libvirt, "VIR_STORAGE_VOL_NETDIR", 4)
def __init__(self, *args, **kwargs):
_StorageObject.__init__(self, *args, **kwargs)
self._input_vol = None
self._pool = None
self._pool_xml = None
self._reflink = False
self._install_finished = threading.Event()
######################
# Non XML properties #
######################
def _get_pool(self):
return self._pool
def _set_pool(self, newpool):
if newpool.info()[0] != libvirt.VIR_STORAGE_POOL_RUNNING:
raise ValueError(_("pool '%s' must be active.") % newpool.name())
self._pool = newpool
self._pool_xml = StoragePool(self.conn,
parsexml=self._pool.XMLDesc(0))
pool = property(_get_pool, _set_pool)
def _get_input_vol(self):
return self._input_vol
def _set_input_vol(self, vol):
if vol is None:
self._input_vol = None
return
if not isinstance(vol, libvirt.virStorageVol):
raise ValueError(_("input_vol must be a virStorageVol"))
self._input_vol = vol
input_vol = property(_get_input_vol, _set_input_vol)
def _get_reflink(self):
return self._reflink
def _set_reflink(self, reflink):
self._reflink = reflink
reflink = property(_get_reflink, _set_reflink)
def sync_input_vol(self, only_format=False):
# Pull parameters from input vol into this class
parsevol = StorageVolume(self.conn,
parsexml=self._input_vol.XMLDesc(0))
self.format = parsevol.format
self.capacity = parsevol.capacity
self.allocation = parsevol.allocation
if only_format:
return
self.pool = self._input_vol.storagePoolLookupByVolume()
##########################
# XML validation helpers #
##########################
@staticmethod
def validate_name(pool, name):
util.validate_name(_("Storage object"), name)
try:
pool.storageVolLookupByName(name)
except libvirt.libvirtError:
return
raise ValueError(_("Name '%s' already in use by another volume." %
name))
def _get_vol_type(self):
if self.type:
if self.type == "file":
return self.TYPE_FILE
elif self.type == "block":
return self.TYPE_BLOCK
elif self.type == "dir":
return self.TYPE_DIR
elif self.type == "network":
return self.TYPE_NETWORK
return self._pool_xml.get_disk_type()
file_type = property(_get_vol_type)
##################
# XML properties #
##################
XML_NAME = "volume"
_XML_PROP_ORDER = ["name", "key", "capacity", "allocation", "format",
"target_path", "permissions"]
type = XMLProperty("./@type")
key = XMLProperty("./key")
capacity = XMLProperty("./capacity", is_int=True)
allocation = XMLProperty("./allocation", is_int=True)
format = XMLProperty("./target/format/@type")
target_path = XMLProperty("./target/path")
backing_store = XMLProperty("./backingStore/path")
backing_format = XMLProperty("./backingStore/format/@type")
lazy_refcounts = XMLProperty(
"./target/features/lazy_refcounts", is_bool=True)
def _detect_backing_store_format(self):
logging.debug("Attempting to detect format for backing_store=%s",
self.backing_store)
from . import diskbackend
vol, pool = diskbackend.manage_path(self.conn, self.backing_store)
if not vol:
logging.debug("Didn't find any volume for backing_store")
return None
# Only set backing format for volumes that support
# the 'format' parameter as we know it, like qcow2 etc.
volxml = StorageVolume(self.conn, vol.XMLDesc(0))
volxml.pool = pool
logging.debug("Found backing store volume XML:\n%s",
volxml.get_xml())
if volxml.supports_property("format"):
logging.debug("Returning format=%s", volxml.format)
return volxml.format
logging.debug("backing_store volume doesn't appear to have "
"a file format we can specify, returning None")
return None
######################
# Public API helpers #
######################
def _supports_format(self):
if self.file_type == self.TYPE_FILE:
return True
if self._pool_xml.type == StoragePool.TYPE_GLUSTER:
return True
return False
def supports_property(self, propname):
if propname == "format":
return self._supports_format()
return hasattr(self, propname)
##################
# Build routines #
##################
def validate(self):
self.validate_name(self.pool, self.name)
if not self.format and self.file_type == self.TYPE_FILE:
self.format = "raw"
if self._prop_is_unset("lazy_refcounts") and self.format == "qcow2":
self.lazy_refcounts = self.conn.check_support(
self.conn.SUPPORT_CONN_QCOW2_LAZY_REFCOUNTS)
if self._pool_xml.type == StoragePool.TYPE_LOGICAL:
if self.allocation != self.capacity:
logging.warning(_("Sparse logical volumes are not supported, "
"setting allocation equal to capacity"))
self.allocation = self.capacity
isfatal, errmsg = self.is_size_conflict()
if isfatal:
raise ValueError(errmsg)
if errmsg:
logging.warning(errmsg)
def install(self, meter=None):
"""
Build and install storage volume from xml
"""
if self.backing_store and not self.backing_format:
self.backing_format = self._detect_backing_store_format()
xml = self.get_xml()
logging.debug("Creating storage volume '%s' with xml:\n%s",
self.name, xml)
t = threading.Thread(target=self._progress_thread,
name="Checking storage allocation",
args=(meter,))
t.setDaemon(True)
meter = util.ensure_meter(meter)
cloneflags = 0
createflags = 0
if (self.format == "qcow2" and
not self.backing_store and
not self.conn.is_really_test() and
self.conn.check_support(
self.conn.SUPPORT_POOL_METADATA_PREALLOC, self.pool)):
createflags |= libvirt.VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA
if self.reflink:
cloneflags |= getattr(libvirt,
"VIR_STORAGE_VOL_CREATE_REFLINK", 1)
try:
self._install_finished.clear()
t.start()
meter.start(size=self.capacity,
text=_("Allocating '%s'") % self.name)
if self.input_vol:
vol = self.pool.createXMLFrom(xml, self.input_vol, cloneflags)
else:
logging.debug("Using vol create flags=%s", createflags)
vol = self.pool.createXML(xml, createflags)
self._install_finished.set()
t.join()
meter.end(self.capacity)
logging.debug("Storage volume '%s' install complete.",
self.name)
return vol
except Exception as e:
logging.debug("Error creating storage volume", exc_info=True)
raise RuntimeError("Couldn't create storage volume "
"'%s': '%s'" % (self.name, str(e)))
def _progress_thread(self, meter):
vol = None
if not meter:
return
while True:
try:
if not vol:
vol = self.pool.storageVolLookupByName(self.name)
vol.info()
break
except Exception:
if self._install_finished.wait(.2):
break
if vol is None:
logging.debug("Couldn't lookup storage volume in prog thread.")
return
while True:
ignore, ignore, alloc = vol.info()
meter.update(alloc)
if self._install_finished.wait(1):
break
def is_size_conflict(self):
"""
Report if requested size exceeds its pool's available amount
:returns: 2 element tuple:
1. True if collision is fatal, false otherwise
2. String message if some collision was encountered.
"""
if not self.pool:
return (False, "")
# pool info is [pool state, capacity, allocation, available]
avail = self.pool.info()[3]
if self.allocation > avail:
return (True, _("There is not enough free space on the storage "
"pool to create the volume. "
"(%d M requested allocation > %d M available)") %
((self.allocation // (1024 * 1024)),
(avail // (1024 * 1024))))
elif self.capacity > avail:
return (False, _("The requested volume capacity will exceed the "
"available pool space when the volume is fully "
"allocated. "
"(%d M requested capacity > %d M available)") %
((self.capacity // (1024 * 1024)),
(avail // (1024 * 1024))))
return (False, "")