# Copyright 2005 Princeton University
+#$Id: vserver.py,v 1.72 2007/08/02 16:01:59 dhozac Exp $
+
import errno
import fcntl
import os
import re
+import pwd
+import signal
import sys
import time
import traceback
+import subprocess
+import resource
-import mountimpl
-import linuxcaps
-import passfdimpl
-import utmp
import vserverimpl
+import cpulimit, bwlimit
-from util_vserver_vars import *
-
-CAP_SAFE = (linuxcaps.CAP_CHOWN |
- linuxcaps.CAP_DAC_OVERRIDE |
- linuxcaps.CAP_DAC_READ_SEARCH |
- linuxcaps.CAP_FOWNER |
- linuxcaps.CAP_FSETID |
- linuxcaps.CAP_KILL |
- linuxcaps.CAP_SETGID |
- linuxcaps.CAP_SETUID |
- linuxcaps.CAP_SETPCAP |
- linuxcaps.CAP_SYS_TTY_CONFIG |
- linuxcaps.CAP_LEASE |
- linuxcaps.CAP_SYS_CHROOT |
- linuxcaps.CAP_SYS_PTRACE)
+from vserverimpl import VS_SCHED_CPU_GUARANTEED as SCHED_CPU_GUARANTEED
+from vserverimpl import DLIMIT_INF
+from vserverimpl import VC_LIM_KEEP
+from vserverimpl import VLIMIT_NSOCK
+from vserverimpl import VLIMIT_OPENFD
+from vserverimpl import VLIMIT_ANON
+from vserverimpl import VLIMIT_SHMEM
#
# these are the flags taken from the kernel linux/vserver/legacy.h
FLAGS_ULIMIT = 64
FLAGS_NAMESPACE = 128
+RLIMITS = { "NSOCK": VLIMIT_NSOCK,
+ "OPENFD": VLIMIT_OPENFD,
+ "ANON": VLIMIT_ANON,
+ "SHMEM": VLIMIT_SHMEM}
+
+# add in the platform supported rlimits
+for entry in resource.__dict__.keys():
+ if entry.find("RLIMIT_")==0:
+ k = entry[len("RLIMIT_"):]
+ if not RLIMITS.has_key(k):
+ RLIMITS[k]=resource.__dict__[entry]
+ else:
+ print "WARNING: duplicate RLIMITS key %s" % k
+
+class NoSuchVServer(Exception): pass
+
+
+class VServerConfig:
+ def __init__(self, name, directory):
+ self.name = name
+ self.dir = directory
+ self.cache = None
+ if not (os.path.isdir(self.dir) and
+ os.access(self.dir, os.R_OK | os.W_OK | os.X_OK)):
+ raise NoSuchVServer, "%s does not exist" % self.dir
+
+ def get(self, option, default = None):
+ try:
+ if self.cache:
+ return self.cache[option]
+ else:
+ f = open(os.path.join(self.dir, option), "r")
+ buf = f.read().rstrip()
+ f.close()
+ return buf
+ except:
+ if default is not None:
+ return default
+ else:
+ raise KeyError, "Key %s is not set for %s" % (option, self.name)
+
+ def update(self, option, value):
+ if self.cache:
+ return
+
+ try:
+ old_umask = os.umask(0022)
+ filename = os.path.join(self.dir, option)
+ try:
+ os.makedirs(os.path.dirname(filename), 0755)
+ except:
+ pass
+ f = open(filename, 'w')
+ if isinstance(value, list):
+ f.write("%s\n" % "\n".join(value))
+ else:
+ f.write("%s\n" % value)
+ f.close()
+ os.umask(old_umask)
+ except:
+ raise
+
+ def unset(self, option):
+ if self.cache:
+ return
+
+ try:
+ filename = os.path.join(self.dir, option)
+ os.unlink(filename)
+ try:
+ os.removedirs(os.path.dirname(filename))
+ except:
+ pass
+ return True
+ except:
+ return False
+
+ def cache_it(self):
+ self.cache = {}
+ def add_to_cache(cache, dirname, fnames):
+ for file in fnames:
+ full_name = os.path.join(dirname, file)
+ if os.path.islink(full_name):
+ fnames.remove(file)
+ elif (os.path.isfile(full_name) and
+ os.access(full_name, os.R_OK)):
+ f = open(full_name, "r")
+ cache[full_name.replace(os.path.join(self.dir, ''),
+ '')] = f.read().rstrip()
+ f.close()
+ os.path.walk(self.dir, add_to_cache, self.cache)
+
-
class VServer:
INITSCRIPTS = [('/etc/rc.vinit', 'start'),
('/etc/rc.d/rc', '%(runlevel)d')]
- def __init__(self, name):
+ def __init__(self, name, vm_id = None, vm_running = None):
self.name = name
- self.config = self.__read_config_file("/etc/vservers.conf")
- self.config.update(self.__read_config_file("/etc/vservers/%s.conf" %
- self.name))
- self.flags = 0
- flags = self.config["S_FLAGS"].split(" ")
- if "lock" in flags:
- self.flags |= FLAGS_LOCK
- if "nproc" in flags:
- self.flags |= FLAGS_NPROC
- self.remove_caps = ~CAP_SAFE
- self.ctx = int(self.config["S_CONTEXT"])
-
- config_var_re = re.compile(r"^ *([A-Z_]+)=(.*)\n?$", re.MULTILINE)
-
- def __read_config_file(self, filename):
-
- f = open(filename, "r")
- data = f.read()
- f.close()
- config = {}
- for m in self.config_var_re.finditer(data):
- (key, val) = m.groups()
- config[key] = val.strip('"')
- return config
+ self.rlimits_changed = False
+ self.dir = "%s/%s" % (vserverimpl.VSERVER_BASEDIR, name)
+ if not (os.path.isdir(self.dir) and
+ os.access(self.dir, os.R_OK | os.W_OK | os.X_OK)):
+ raise NoSuchVServer, "no such vserver: " + name
+ self.config = VServerConfig(name, "/etc/vservers/%s" % name)
+ self.remove_caps = ~vserverimpl.CAP_SAFE;
+ if vm_id == None:
+ vm_id = int(self.config.get('context'))
+ self.ctx = vm_id
+ if vm_running == None:
+ vm_running = self.is_running()
+ self.vm_running = vm_running
+
+ def have_limits_changed(self):
+ return self.rlimits_changed
+
+ def set_rlimit_limit(self,type,hard,soft,minimum):
+ """Generic set resource limit function for vserver"""
+ global RLIMITS
+ changed = False
+ try:
+ old_hard, old_soft, old_minimum = self.get_rlimit_limit(type)
+ if old_hard != VC_LIM_KEEP and old_hard <> hard: changed = True
+ if old_soft != VC_LIM_KEEP and old_soft <> soft: changed = True
+ if old_minimum != VC_LIM_KEEP and old_minimum <> minimum: changed = True
+ self.rlimits_changed = self.rlimits_changed or changed
+ except OSError, e:
+ if self.is_running(): print "Unexpected error with getrlimit for running context %d" % self.ctx
+
+ resource_type = RLIMITS[type]
+ try:
+ ret = vserverimpl.setrlimit(self.ctx,resource_type,hard,soft,minimum)
+ except OSError, e:
+ if self.is_running(): print "Unexpected error with setrlimit for running context %d" % self.ctx
+
+ def set_rlimit_config(self,type,hard,soft,minimum):
+ """Generic set resource limit function for vserver"""
+ if hard <> VC_LIM_KEEP:
+ self.config.update('rlimits/%s.hard' % type.lower(), hard)
+ if soft <> VC_LIM_KEEP:
+ self.config.update('rlimits/%s.soft' % type.lower(), soft)
+ if minimum <> VC_LIM_KEEP:
+ self.config.update('rlimits/%s.min' % type.lower(), minimum)
+ self.set_rlimit_limit(type,hard,soft,minimum)
+
+ def get_rlimit_limit(self,type):
+ """Generic get resource configuration function for vserver"""
+ global RLIMITS
+ resource_type = RLIMITS[type]
+ try:
+ ret = vserverimpl.getrlimit(self.ctx,resource_type)
+ except OSError, e:
+ print "Unexpected error with getrlimit for context %d" % self.ctx
+ ret = self.get_rlimit_config(type)
+ return ret
+
+ def get_rlimit_config(self,type):
+ """Generic get resource configuration function for vserver"""
+ hard = int(self.config.get("rlimits/%s.hard"%type.lower(),VC_LIM_KEEP))
+ soft = int(self.config.get("rlimits/%s.soft"%type.lower(),VC_LIM_KEEP))
+ minimum = int(self.config.get("rlimits/%s.min"%type.lower(),VC_LIM_KEEP))
+ return (hard,soft,minimum)
+
+ def set_capabilities(self, capabilities):
+ return vserverimpl.setbcaps(self.ctx, vserverimpl.text2bcaps(capabilities))
+
+ def set_capabilities_config(self, capabilities):
+ self.config.update('bcapabilities', capabilities)
+ self.set_capabilities(capabilities)
+
+ def get_capabilities(self):
+ return vserverimpl.bcaps2text(vserverimpl.getbcaps(self.ctx))
+
+ def get_capabilities_config(self):
+ return self.config.get('bcapabilities', '')
+
+ def set_ipaddresses(self, addresses):
+ vserverimpl.netremove(self.ctx, "all")
+ for a in addresses.split(","):
+ vserverimpl.netadd(self.ctx, a)
+
+ def set_ipaddresses_config(self, addresses):
+ i = 0
+ for a in addresses.split(","):
+ self.config.update("interfaces/%d/ip" % i, a)
+ i += 1
+ while self.config.unset("interfaces/%d/ip" % i):
+ i += 1
+ self.set_ipaddresses(addresses)
+
+ def get_ipaddresses_config(self):
+ i = 0
+ ret = []
+ while True:
+ r = self.config.get("interfaces/%d/ip" % i, '')
+ if r == '':
+ break
+ ret += [r]
+ i += 1
+ return ",".join(ret)
- def __do_chroot(self):
+ def get_ipaddresses(self):
+ # No clean way to do this right now.
+ return None
- return os.chroot("%s/%s" % (VROOTDIR, self.name))
+ def __do_chroot(self):
+ self.config.cache_it()
+ os.chroot(self.dir)
+ os.chdir("/")
- def open(self, filename, mode = "r", bufsize = -1):
+ def chroot_call(self, fn, *args):
- (sendsock, recvsock) = passfdimpl.socketpair()
- child_pid = os.fork()
- if child_pid == 0:
+ cwd_fd = os.open(".", os.O_RDONLY)
+ try:
+ root_fd = os.open("/", os.O_RDONLY)
try:
- # child process
self.__do_chroot()
- f = open(filename, mode)
- passfdimpl.sendmsg(f.fileno(), sendsock)
- os._exit(0)
- except EnvironmentError, ex:
- (result, errmsg) = (ex.errno, ex.strerror)
- except Exception, ex:
- (result, errmsg) = (255, str(ex))
- os.write(sendsock, errmsg)
- os._exit(result)
+ result = fn(*args)
+ finally:
+ os.fchdir(root_fd)
+ os.chroot(".")
+ os.fchdir(cwd_fd)
+ os.close(root_fd)
+ finally:
+ os.close(cwd_fd)
+ return result
+
+ def set_disklimit(self, block_limit):
+ # block_limit is in kB
+ if block_limit == 0:
+ try:
+ vserverimpl.unsetdlimit(self.dir, self.ctx)
+ except OSError, e:
+ print "Unexpected error with unsetdlimit for context %d" % self.ctx
+ return
- # parent process
+ if self.vm_running:
+ block_usage = vserverimpl.DLIMIT_KEEP
+ inode_usage = vserverimpl.DLIMIT_KEEP
+ else:
+ # init_disk_info() must have been called to get usage values
+ block_usage = self.disk_blocks
+ inode_usage = self.disk_inodes
- # XXX - need this since a lambda can't raise an exception
- def __throw(ex):
- raise ex
- os.close(sendsock)
- throw = lambda : __throw(Exception(errmsg))
- while True:
- try:
- (pid, status) = os.waitpid(child_pid, 0)
- if os.WIFEXITED(status):
- result = os.WEXITSTATUS(status)
- if result != 255:
- errmsg = os.strerror(result)
- throw = lambda : __throw(IOError(result, errmsg))
- else:
- errmsg = "unexpected exception in child"
- else:
- result = -1
- errmsg = "child killed"
- break
- except OSError, ex:
- if ex.errno != errno.EINTR:
- os.close(recvsock)
- raise ex
- fcntl.fcntl(recvsock, fcntl.F_SETFL, os.O_NONBLOCK)
try:
- (fd, errmsg) = passfdimpl.recvmsg(recvsock)
+ vserverimpl.setdlimit(self.dir,
+ self.ctx,
+ block_usage,
+ block_limit,
+ inode_usage,
+ vserverimpl.DLIMIT_INF, # inode limit
+ 2) # %age reserved for root
+ except OSError, e:
+ print "Unexpected error with setdlimit for context %d" % self.ctx
+
+
+ self.config.update('dlimits/0/space_total', block_limit)
+
+ def is_running(self):
+ return vserverimpl.isrunning(self.ctx)
+
+ def get_disklimit(self):
+
+ try:
+ (self.disk_blocks, block_limit, self.disk_inodes, inode_limit,
+ reserved) = vserverimpl.getdlimit(self.dir, self.ctx)
except OSError, ex:
- if ex.errno != errno.EAGAIN:
- throw = lambda : __throw(ex)
- fd = 0
- os.close(recvsock)
- if not fd:
- throw()
+ if ex.errno != errno.ESRCH:
+ raise
+ # get here if no vserver disk limit has been set for xid
+ block_limit = -1
- return os.fdopen(fd, mode, bufsize)
+ return block_limit
- def __do_chcontext(self, state_file = None):
+ def set_sched_config(self, cpu_share, sched_flags):
- vserverimpl.chcontext(self.ctx, self.remove_caps)
- if not state_file:
- return
- print >>state_file, "S_CONTEXT=%d" % self.ctx
- print >>state_file, "S_PROFILE=%s" % self.config.get("S_PROFILE", "")
- state_file.close()
+ """ Write current CPU scheduler parameters to the vserver
+ configuration file. This method does not modify the kernel CPU
+ scheduling parameters for this context. """
+
+ if sched_flags & SCHED_CPU_GUARANTEED:
+ cpu_guaranteed = cpu_share
+ else:
+ cpu_guaranteed = 0
+ self.config.update('sched/fill-rate2', cpu_share)
+ self.config.update('sched/fill-rate', cpu_guaranteed)
+
+ if self.vm_running:
+ self.set_sched(cpu_share, sched_flags)
+
+ def set_sched(self, cpu_share, sched_flags = 0):
+ """ Update kernel CPU scheduling parameters for this context. """
+ vserverimpl.setsched(self.ctx, cpu_share, sched_flags)
+
+ def get_sched(self):
+ # have no way of querying scheduler right now on a per vserver basis
+ return (-1, False)
+
+ def set_bwlimit(self, minrate = bwlimit.bwmin, maxrate = None,
+ exempt_min = None, exempt_max = None,
+ share = None, dev = "eth0"):
+
+ if minrate is None:
+ bwlimit.off(self.ctx, dev)
+ else:
+ bwlimit.on(self.ctx, dev, share,
+ minrate, maxrate, exempt_min, exempt_max)
+
+ def get_bwlimit(self, dev = "eth0"):
+
+ result = bwlimit.get(self.ctx)
+ # result of bwlimit.get is (ctx, share, minrate, maxrate)
+ if result:
+ result = result[1:]
+ return result
+
+ def open(self, filename, mode = "r", bufsize = -1):
+
+ return self.chroot_call(open, filename, mode, bufsize)
+
+ def __do_chcontext(self, state_file):
+
+ if state_file:
+ print >>state_file, "%u" % self.ctx
+ state_file.close()
+
+ if vserverimpl.chcontext(self.ctx, vserverimpl.text2bcaps(self.get_capabilities_config())):
+ self.set_resources()
+ vserverimpl.setup_done(self.ctx)
def __prep(self, runlevel, log):
([], filter_fn))[0]
garbage += filter(os.path.isfile, map((LOCKDIR + "/").__add__,
os.listdir(LOCKDIR)))
- for f in garbage:
- os.unlink(f)
+ if False:
+ for f in garbage:
+ os.unlink(f)
# set the initial runlevel
f = open(RUNDIR + "/utmp", "w")
- utmp.set_runlevel(f, runlevel)
+ vserverimpl.setrunlevel(f, runlevel)
f.close()
# mount /proc and /dev/pts
- self.__do_mount("none", "/proc", "proc")
+ self.__do_mount("none", self.dir, "/proc", "proc")
# XXX - magic mount options
- self.__do_mount("none", "/dev/pts", "devpts", 0, "gid=5,mode=0620")
+ self.__do_mount("none", self.dir, "/dev/pts", "devpts", 0, "gid=5,mode=0620")
def __do_mount(self, *mount_args):
try:
- mountimpl.mount(*mount_args)
+ vserverimpl.mount(*mount_args)
except OSError, ex:
if ex.errno == errno.EBUSY:
# assume already mounted
raise ex
def enter(self):
-
- state_file = open("/var/run/vservers/%s.ctx" % self.name, "w")
self.__do_chroot()
- self.__do_chcontext(state_file)
+ self.__do_chcontext(None)
def start(self, wait, runlevel = 3):
+ self.vm_running = True
+ self.rlimits_changed = False
child_pid = os.fork()
if child_pid == 0:
os.setsid()
# open state file to record vserver info
- state_file = open("/var/run/vservers/%s.ctx" % self.name, "w")
+ state_file = open("/var/run/vservers/%s" % self.name, "w")
# use /dev/null for stdin, /var/log/boot.log for stdout/err
- os.close(0)
- os.close(1)
- os.open("/dev/null", os.O_RDONLY)
+ fd = os.open("/dev/null", os.O_RDONLY)
+ if fd != 0:
+ os.dup2(fd, 0)
+ os.close(fd)
self.__do_chroot()
log = open("/var/log/boot.log", "w", 0)
+ if log.fileno() != 1:
+ os.dup2(log.fileno(), 1)
os.dup2(1, 2)
print >>log, ("%s: starting the virtual server %s" %
# execute each init script in turn
# XXX - we don't support all scripts that vserver script does
- cmd_pid = 0
- for cmd in self.INITSCRIPTS + [None]:
- # wait for previous command to terminate, unless it
- # is the last one and the caller has specified to wait
- if cmd_pid and (cmd != None or wait):
- try:
- os.waitpid(cmd_pid, 0)
- except:
- print >>log, "error waiting for %s:" % cmd_pid
- traceback.print_exc()
-
- # end of list
- if cmd == None:
- os._exit(0)
-
- # fork and exec next command
- cmd_pid = os.fork()
- if cmd_pid == 0:
- try:
- # enter vserver context
- self.__do_chcontext(state_file)
- arg_subst = { 'runlevel': runlevel }
- cmd_args = [cmd[0]] + map(lambda x: x % arg_subst,
- cmd[1:])
- print >>log, "executing '%s'" % " ".join(cmd_args)
- os.execl(cmd[0], *cmd_args)
- except:
- traceback.print_exc()
- os._exit(1)
- else:
- # don't want to write state_file multiple times
- state_file = None
+ self.__do_chcontext(state_file)
+ for cmd in self.INITSCRIPTS:
+ try:
+ # enter vserver context
+ arg_subst = { 'runlevel': runlevel }
+ cmd_args = [cmd[0]] + map(lambda x: x % arg_subst,
+ cmd[1:])
+ print >>log, "executing '%s'" % " ".join(cmd_args)
+ os.spawnvp(os.P_NOWAIT,cmd[0],cmd_args)
+ except:
+ traceback.print_exc()
+ os._exit(1)
# we get here due to an exception in the top-level child process
except Exception, ex:
# parent process
return child_pid
+
+ def set_resources(self):
+
+ """ Called when vserver context is entered for first time,
+ should be overridden by subclass. """
+
+ pass
+
+ def init_disk_info(self):
+ cmd = "/usr/sbin/vdu --script --space --inodes --blocksize 1024 --xid %d %s" % (self.ctx, self.dir)
+ p = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE,
+ stdout=subprocess.PIPE, stderr=subprocess.PIPE,
+ close_fds=True)
+ p.stdin.close()
+ line = p.stdout.readline()
+ if not line:
+ sys.stderr.write(p.stderr.read())
+ p.stdout.close()
+ p.stderr.close()
+ ret = p.wait()
+
+ (space, inodes) = line.split()
+ self.disk_inodes = int(inodes)
+ self.disk_blocks = int(space)
+ #(self.disk_inodes, self.disk_blocks) = vduimpl.vdu(self.dir)
+
+ return self.disk_blocks * 1024
+
+ def stop(self, signal = signal.SIGKILL):
+ vserverimpl.killall(self.ctx, signal)
+ self.vm_running = False
+ self.rlimits_changed = False
+
+
+
+def create(vm_name, static = False, ctor = VServer):
+
+ options = ['vuseradd']
+ if static:
+ options += ['--static']
+ ret = os.spawnvp(os.P_WAIT, 'vuseradd', options + [vm_name])
+ if !os.WIFEXITED(ret) || os.WEXITSTATUS(ret) != 0:
+ out = "system command ('%s') " % options
+ if os.WIFEXITED(ret):
+ out += "failed, rc = %d" % os.WEXITSTATUS(ret)
+ else:
+ out += "killed by signal %d" % os.WTERMSIG(ret)
+ raise SystemError, out
+ vm_id = pwd.getpwnam(vm_name)[2]
+
+ return ctor(vm_name, vm_id)
git://git.onelab.eu / util-vserver.git / blobdiff