virt-manager/virtinst/storage.py

746 lines
24 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 threading
import libvirt
from . import generatename
from . import progress
from .logger import log
from .xmlbuilder import XMLBuilder, XMLChildProperty, XMLProperty
_DEFAULT_DEV_TARGET = "/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 _preferred_default_pool_path(conn):
path = "/var/lib/libvirt/images"
if conn.is_unprivileged():
path = os.path.expanduser("~/.local/share/libvirt/images")
return path
def _lookup_poolxml_by_path(conn, path):
for poolxml in conn.fetch_all_pools():
xml_path = poolxml.target_path
if xml_path is not None and os.path.abspath(xml_path) == path:
return poolxml
return None
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
"""
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"
@staticmethod
def pool_list_from_sources(conn, pool_type):
"""
Return a list of StoragePool instances built from libvirt's pool
source enumeration (if supported).
:param conn: Libvirt connection
:param pool_type: Pool type string from I{Types}
"""
source_xml = "<source/>"
try:
xml = conn.findStoragePoolSources(pool_type, source_xml, 0)
except Exception as e: # pragma: no cover
if conn.support.is_error_nosupport(e):
return []
raise
log.debug("Libvirt returned pool sources XML:\n%s", xml)
import xml.etree.ElementTree as ET
root = ET.fromstring(xml)
# We implicitly only support this for pool TYPE_LOGICAL
ret = [e.text for e in root.findall("./source/name")]
log.debug("Sources returning: %s", ret)
return ret
@staticmethod
def lookup_default_pool(conn):
"""
Helper to lookup the default pool. It will return one of
* The pool named 'default'
* If that doesn't exist, the pool pointing to the default path
* Otherwise None
"""
name = "default"
path = _preferred_default_pool_path(conn)
poolxml = None
for trypool in conn.fetch_all_pools():
if trypool.name == name:
poolxml = trypool
break
else:
poolxml = _lookup_poolxml_by_path(conn, path)
if poolxml:
log.debug("Found default pool name=%s target=%s",
poolxml.name, poolxml.target_path)
return poolxml
@staticmethod
def build_default_pool(conn):
"""
Attempt to lookup the 'default' pool, but if it doesn't exist,
create it
"""
poolxml = StoragePool.lookup_default_pool(conn)
if poolxml:
return poolxml
try:
name = "default"
path = _preferred_default_pool_path(conn)
log.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: # pragma: no cover
raise RuntimeError(
(_("Couldn't create default storage pool '%s'") % path) +
(": %s" % str(e)))
@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
"""
poolxml = _lookup_poolxml_by_path(conn, path)
if not poolxml:
return None
return conn.storagePoolLookupByName(poolxml.name)
@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
return generatename.generate_name(basename, cb, **kwargs)
@staticmethod
def ensure_pool_is_running(pool_object, refresh=False):
"""
If the passed vmmStoragePool isn't running, start it.
:param pool_object: vmmStoragePool to check/start
:param refresh: If True, run refresh() as well
"""
if pool_object.info()[0] != libvirt.VIR_STORAGE_POOL_RUNNING:
log.debug("starting pool=%s", pool_object.name())
pool_object.create(0)
if refresh:
log.debug("refreshing pool=%s", pool_object.name())
pool_object.refresh(0)
######################
# Validation helpers #
######################
@staticmethod
def validate_name(conn, name):
XMLBuilder.validate_generic_name(_("Storage object"), name)
try:
conn.storagePoolLookupByName(name)
except libvirt.libvirtError:
return
raise ValueError(_("Name '%s' already in use by another pool." %
name)) # pragma: no cover
def default_target_path(self):
if not self.supports_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(
_preferred_default_pool_path(self.conn), self.name)
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
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):
if not self.supports_source_name():
return None
if self.type == StoragePool.TYPE_RBD:
return "rbd"
if self.type == StoragePool.TYPE_GLUSTER:
return "gv0"
##############
# 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_target_path(self):
return self.type in [
self.TYPE_DIR, self.TYPE_FS, self.TYPE_NETFS,
self.TYPE_ISCSI,
self.TYPE_SCSI, self.TYPE_MPATH]
def supports_source_name(self):
return self.type in [self.TYPE_LOGICAL, self.TYPE_GLUSTER,
self.TYPE_RBD, self.TYPE_SHEEPDOG, self.TYPE_ZFS]
def supports_source_path(self):
return self.type in [
self.TYPE_FS, self.TYPE_NETFS,
self.TYPE_DISK, self.TYPE_ISCSI, self.TYPE_SCSI,
self.TYPE_GLUSTER]
def supports_hosts(self):
return self.type in [
self.TYPE_NETFS, self.TYPE_ISCSI, self.TYPE_GLUSTER,
self.TYPE_RBD, self.TYPE_SHEEPDOG]
def supports_format(self):
return self.type in [self.TYPE_FS, self.TYPE_NETFS, self.TYPE_DISK]
def supports_iqn(self):
return self.type in [self.TYPE_ISCSI]
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:
if self.type == self.TYPE_DISK:
# disk is a bit special, in that it demands a target path,
# but basically can't handle anything other than /dev
self.target_path = _DEFAULT_DEV_TARGET
else:
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_format():
self.format = "auto"
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.
"""
xml = self.get_xml()
log.debug("Creating storage pool '%s' with xml:\n%s",
self.name, xml)
meter = progress.ensure_meter(meter)
try:
pool = self.conn.storagePoolDefineXML(xml, 0)
except Exception as e: # pragma: no cover
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: # pragma: no cover
errmsg = _("Could not build storage pool: %s") % str(e)
if create and not errmsg:
try:
pool.create(0)
except Exception as e: # pragma: no cover
errmsg = _("Could not start storage pool: %s") % str(e)
if autostart and not errmsg:
try:
pool.setAutostart(True)
except Exception as e: # pragma: no cover
errmsg = _("Could not set pool autostart flag: %s") % str(e)
if errmsg: # pragma: no cover
# Try and clean up the leftover pool
try:
pool.undefine()
except Exception as e:
log.debug("Error cleaning up pool after failure: %s",
str(e))
raise RuntimeError(errmsg)
self.conn.cache_new_pool(pool)
return pool
def _progress_thread(volname, pool, meter, event):
vol = None
if not meter:
return # pragma: no cover
while True:
try:
if not vol:
vol = pool.storageVolLookupByName(volname)
vol.info() # pragma: no cover
break # pragma: no cover
except Exception:
if event.wait(.2):
break
if vol is None:
log.debug("Couldn't lookup storage volume in prog thread.")
return
while True: # pragma: no cover
dummy1, dummy2, alloc = vol.info()
meter.update(alloc)
if event.wait(1):
break
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(conn, pool_object, basename, collideguest=None, **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
:param collideguest: Guest object. If specified, also check to
ensure we don't collide with any disk paths there
"""
collidelist = []
if collideguest:
pooltarget = None
poolname = pool_object.name()
for poolxml in conn.fetch_all_pools():
if poolxml.name == poolname:
pooltarget = poolxml.target_path
break
for disk in collideguest.devices.disk:
if (pooltarget and disk.path and
os.path.dirname(disk.path) == pooltarget):
collidelist.append(os.path.basename(disk.path))
def cb(tryname):
if tryname in collidelist:
return True
return generatename.check_libvirt_collision(
pool_object.storageVolLookupByName, tryname)
StoragePool.ensure_pool_is_running(pool_object, refresh=True)
return generatename.generate_name(basename, cb, **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
######################
# Non XML properties #
######################
def _get_pool(self):
return self._pool
def _set_pool(self, newpool):
StoragePool.ensure_pool_is_running(newpool)
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):
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):
XMLBuilder.validate_generic_name(_("Storage object"), name)
try:
pool.storageVolLookupByName(name)
except libvirt.libvirtError:
return
raise ValueError(_("Name '%s' already in use by another volume." %
name)) # pragma: no cover
def _get_vol_type(self):
if self.type: # pragma: no cover
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):
log.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: # pragma: no cover
log.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
log.debug("Found backing store volume XML:\n%s",
volxml.get_xml())
if not volxml.supports_format(): # pragma: no cover
log.debug("backing_store volume doesn't appear to have "
"a file format we can specify, returning None")
return None
log.debug("Returning format=%s", volxml.format)
return volxml.format
######################
# 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
##################
# 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.support.conn_qcow2_lazy_refcounts()
if self._pool_xml.type == StoragePool.TYPE_LOGICAL:
if self.allocation != self.capacity:
log.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:
log.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()
log.debug("Creating storage volume '%s' with xml:\n%s",
self.name, xml)
cloneflags = 0
createflags = 0
if (self.format == "qcow2" and
not self.backing_store and
self.conn.support.pool_metadata_prealloc(self.pool)):
createflags |= libvirt.VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA
if self.capacity == self.allocation:
# For cloning, this flag will make libvirt+qemu-img preallocate
# the new disk image
cloneflags |= libvirt.VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA
if self.reflink:
cloneflags |= getattr(libvirt,
"VIR_STORAGE_VOL_CREATE_REFLINK", 1)
event = threading.Event()
meter = progress.ensure_meter(meter)
t = threading.Thread(target=_progress_thread,
name="Checking storage allocation",
args=(self.name, self.pool, meter, event))
t.setDaemon(True)
try:
t.start()
meter.start(size=self.capacity,
text=_("Allocating '%s'") % self.name)
if self.conn.is_really_test():
# Test suite doesn't support any flags, so reset them
createflags = 0
cloneflags = 0
if self.input_vol:
vol = self.pool.createXMLFrom(xml, self.input_vol, cloneflags)
else:
log.debug("Using vol create flags=%s", createflags)
vol = self.pool.createXML(xml, createflags)
meter.end(self.capacity)
log.debug("Storage volume '%s' install complete.", self.name)
return vol
except Exception as e:
log.debug("Error creating storage volume", exc_info=True)
raise RuntimeError("Couldn't create storage volume "
"'%s': '%s'" % (self.name, str(e)))
finally:
event.set()
t.join()
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:
msg = (_("There is not enough free space on the storage "
"pool to create the volume. (%(mem1)s M requested "
"allocation > %(mem2)s M available)") %
{"mem1": (self.allocation // (1024 * 1024)),
"mem2": (avail // (1024 * 1024))})
return (True, msg)
elif self.capacity > avail:
msg = (_("The requested volume capacity will exceed the "
"available pool space when the volume is fully "
"allocated. (%(mem1)s M requested "
"capacity > %(mem2)s M available)") %
{"mem1": (self.capacity // (1024 * 1024)),
"mem2": (avail // (1024 * 1024))})
return (False, msg)
return (False, "")