"""LibVirt slivers"""
import sys
import os, os.path
import re
import subprocess
import pprint
import random
import libvirt
from account import Account
import logger
import plnode.bwlimit as bwlimit
import cgroups
STATES = {
libvirt.VIR_DOMAIN_NOSTATE: 'no state',
libvirt.VIR_DOMAIN_RUNNING: 'running',
libvirt.VIR_DOMAIN_BLOCKED: 'blocked on resource',
libvirt.VIR_DOMAIN_PAUSED: 'paused by user',
libvirt.VIR_DOMAIN_SHUTDOWN: 'being shut down',
libvirt.VIR_DOMAIN_SHUTOFF: 'shut off',
libvirt.VIR_DOMAIN_CRASHED: 'crashed',
}
REASONS = {
libvirt.VIR_CONNECT_CLOSE_REASON_ERROR: 'Misc I/O error',
libvirt.VIR_CONNECT_CLOSE_REASON_EOF: 'End-of-file from server',
libvirt.VIR_CONNECT_CLOSE_REASON_KEEPALIVE: 'Keepalive timer triggered',
libvirt.VIR_CONNECT_CLOSE_REASON_CLIENT: 'Client requested it',
}
connections = dict()
# Common Libvirt code
class Sliver_Libvirt(Account):
# Helper methods
@staticmethod
def getConnection(sliver_type):
# TODO: error checking
# vtype is of the form sliver.[LXC/QEMU] we need to lower case to lxc/qemu
vtype = sliver_type.split('.')[1].lower()
uri = vtype + '://'
return connections.setdefault(uri, libvirt.open(uri))
def __init__(self, rec):
self.name = rec['name']
logger.verbose ('sliver_libvirt: %s init'%(self.name))
# Assume the directory with the image and config files
# are in place
self.keys = ''
self.rspec = {}
self.slice_id = rec['slice_id']
self.enabled = True
self.conn = Sliver_Libvirt.getConnection(rec['type'])
self.xid = bwlimit.get_xid(self.name)
dom = None
try:
dom = self.conn.lookupByName(self.name)
except:
logger.log('sliver_libvirt: Domain %s does not exist. ' \
'Will try to create it again.' % (self.name))
self.__class__.create(rec['name'], rec)
dom = self.conn.lookupByName(self.name)
self.dom = dom
@staticmethod
def dom_details (dom):
output=""
output += " id=%s - OSType=%s"%(dom.ID(),dom.OSType())
# calling state() seems to be working fine
(state,reason)=dom.state()
output += " state=%s, reason=%s"%(STATES.get(state,state),REASONS.get(reason,reason))
try:
# try to use info() - this however does not work for some reason on f20
# info cannot get info operation failed: Cannot read cputime for domain
[state, maxmem, mem, ncpu, cputime] = dom.info()
output += " [info: maxmem = %s, mem = %s, ncpu = %s, cputime = %s]" % (STATES.get(state, state), maxmem, mem, ncpu, cputime)
except:
# too bad but libvirt.py prints out stuff on stdout when this fails, don't know how to get rid of that..
output += " [info: not available]"
return output
def __repr__(self):
''' Helper method to get a "nice" output of the domain struct for debug purposes'''
output="Domain %s"%self.name
dom=self.dom
if dom is None:
output += " [no attached dom ?!?]"
else:
output += Sliver_Libvirt.dom_details (dom)
return output
# Thierry : I am not quite sure if /etc/libvirt/lxc/<>.xml holds a reliably up-to-date
# copy of the sliver XML config; I feel like issuing a virsh dumpxml first might be safer
def repair_veth(self):
# See workaround email, 2-14-2014, "libvirt 1.2.1 rollout"
xml = open("/etc/libvirt/lxc/%s.xml" % self.name).read()
veths = re.findall("", xml)
veths = [x[13:-3] for x in veths]
for veth in veths:
command = ["ip", "link", "delete", veth]
logger.log_call(command)
logger.log("trying to redefine the VM")
command = ["virsh", "define", "/etc/libvirt/lxc/%s.xml" % self.name]
logger.log_call(command)
def start(self, delay=0):
''' Just start the sliver '''
logger.verbose('sliver_libvirt: %s start'%(self.name))
# Check if it's running to avoid throwing an exception if the
# domain was already running, create actually means start
if not self.is_running():
try:
self.dom.create()
except Exception, e:
# XXX smbaker: attempt to resolve slivers that are stuck in
# "failed to allocate free veth".
if "ailed to allocate free veth" in str(e):
logger.log("failed to allocate free veth on %s" % self.name)
self.repair_veth()
logger.log("trying dom.create again")
self.dom.create()
else:
raise
else:
logger.verbose('sliver_libvirt: sliver %s already started'%(self.name))
# After the VM is started... we can play with the virtual interface
# Create the ebtables rule to mark the packets going out from the virtual
# interface to the actual device so the filter canmatch against the mark
bwlimit.ebtables("-A INPUT -i veth%d -j mark --set-mark %d" % \
(self.xid, self.xid))
def stop(self):
logger.verbose('sliver_libvirt: %s stop'%(self.name))
# Remove the ebtables rule before stopping
bwlimit.ebtables("-D INPUT -i veth%d -j mark --set-mark %d" % \
(self.xid, self.xid))
try:
self.dom.destroy()
except:
logger.log_exc("in sliver_libvirt.stop",name=self.name)
def is_running(self):
''' Return True if the domain is running '''
(state,_) = self.dom.state()
result = (state == libvirt.VIR_DOMAIN_RUNNING)
logger.verbose('sliver_libvirt.is_running: %s => %s'%(self,result))
return result
def configure(self, rec):
#sliver.[LXC/QEMU] tolower case
#sliver_type = rec['type'].split('.')[1].lower()
#BASE_DIR = '/cgroup/libvirt/%s/%s/'%(sliver_type, self.name)
# Disk allocation
# No way through cgroups... figure out how to do that with user/dir quotas.
# There is no way to do quota per directory. Chown-ing would create
# problems as username namespaces are not yet implemented (and thus, host
# and containers share the same name ids
# Btrfs support quota per volumes
if rec.has_key("rspec") and rec["rspec"].has_key("tags"):
if cgroups.get_cgroup_path(self.name) == None:
# If configure is called before start, then the cgroups won't exist
# yet. NM will eventually re-run configure on the next iteration.
# TODO: Add a post-start configure, and move this stuff there
logger.log("Configure: postponing tag check on %s as cgroups are not yet populated" % self.name)
else:
tags = rec["rspec"]["tags"]
# It will depend on the FS selection
if tags.has_key('disk_max'):
disk_max = tags['disk_max']
if disk_max == 0:
# unlimited
pass
else:
# limit to certain number
pass
# Memory allocation
if tags.has_key('memlock_hard'):
mem = str(int(tags['memlock_hard']) * 1024) # hard limit in bytes
cgroups.write(self.name, 'memory.limit_in_bytes', mem, subsystem="memory")
if tags.has_key('memlock_soft'):
mem = str(int(tags['memlock_soft']) * 1024) # soft limit in bytes
cgroups.write(self.name, 'memory.soft_limit_in_bytes', mem, subsystem="memory")
# CPU allocation
# Only cpu_shares until figure out how to provide limits and guarantees
# (RT_SCHED?)
if tags.has_key('cpu_share'):
cpu_share = tags['cpu_share']
cgroups.write(self.name, 'cpu.shares', cpu_share)
# Call the upper configure method (ssh keys...)
Account.configure(self, rec)
@staticmethod
def get_unique_vif():
return 'veth%s' % random.getrandbits(32)
# A placeholder until we get true VirtualInterface objects
@staticmethod
def get_interfaces_xml(rec):
xml = """
""" % (Sliver_Libvirt.get_unique_vif())
try:
tags = rec['rspec']['tags']
if 'interface' in tags:
interfaces = eval(tags['interface'])
if not isinstance(interfaces, (list, tuple)):
# if interface is not a list, then make it into a singleton list
interfaces = [interfaces]
tag_xml = ""
for interface in interfaces:
if 'vlan' in interface:
vlanxml = "" % interface['vlan']
else:
vlanxml = ""
if 'bridge' in interface:
tag_xml = tag_xml + """
%s
""" % (interface['bridge'], vlanxml, Sliver_Libvirt.get_unique_vif())
else:
tag_xml = tag_xml + """
""" % (Sliver_Libvirt.get_unique_vif())
xml = tag_xml
logger.log('sliver_libvirty.py: interface XML is: %s' % xml)
except:
logger.log('sliver_libvirt.py: ERROR parsing "interface" tag for slice %s' % rec['name'])
logger.log('sliver_libvirt.py: tag value: %s' % tags['interface'])
return xml