import fcntl
import os
import re
+import pwd
import signal
import sys
import time
import traceback
import mountimpl
-import passfdimpl
+import runcmd
import utmp
import vserverimpl, vduimpl
import cpulimit, bwlimit
+from vserverimpl import VS_SCHED_CPU_GUARANTEED as SCHED_CPU_GUARANTEED
+from vserverimpl import DLIMIT_INF
+# $Id$
#
# these are the flags taken from the kernel linux/vserver/legacy.h
FLAGS_NAMESPACE = 128
-
+
+class NoSuchVServer(Exception): pass
+
+
+
class VServer:
INITSCRIPTS = [('/etc/rc.vinit', 'start'),
('/etc/rc.d/rc', '%(runlevel)d')]
- def __init__(self, name, vm_id, vm_running = False, resources = {}):
+ def __init__(self, name, vm_id = None, vm_running = False):
self.name = name
self.config_file = "/etc/vservers/%s.conf" % name
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 Exception, "no such vserver: " + name
+ raise NoSuchVServer, "no such vserver: " + name
self.config = {}
for config_file in ["/etc/vservers.conf", self.config_file]:
try:
if ex.errno != errno.ENOENT:
raise
self.remove_caps = ~vserverimpl.CAP_SAFE;
+ if vm_id == None:
+ vm_id = int(self.config['S_CONTEXT'])
self.ctx = vm_id
self.vm_running = vm_running
- self.resources = resources
config_var_re = re.compile(r"^ *([A-Z_]+)=(.*)\n?$", re.MULTILINE)
f.close()
todo = newvars.copy()
changed = False
+ offset = 0
for m in self.config_var_re.finditer(data):
(key, val) = m.groups()
newval = todo.pop(key, None)
if newval != None:
- data = data[:m.start(2)] + str(newval) + data[m.end(2):]
+ data = data[:offset+m.start(2)] + str(newval) + data[offset+m.end(2):]
+ offset += len(str(newval)) - (m.end(2)-m.start(2))
changed = True
for (newkey, newval) in todo.items():
data += "%s=%s\n" % (newkey, newval)
f.write(data)
f.close()
- # 'copy' original file, rename new to original
- backup = filename + ".old"
- try:
- os.unlink(backup)
- except OSError, ex:
- if ex.errno != errno.ENOENT:
- raise
- os.link(filename, backup)
+ # replace old file with new
os.rename(newfile, filename)
def __do_chroot(self):
os.chroot(self.dir)
os.chdir("/")
+ def chroot_call(self, fn, *args):
+
+ cwd_fd = os.open(".", os.O_RDONLY)
+ try:
+ root_fd = os.open("/", os.O_RDONLY)
+ try:
+ self.__do_chroot()
+ 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
return block_limit
- def set_sched(self, cpu_share):
+ def set_sched_config(self, cpu_share, sched_flags):
+
+ """ Write current CPU scheduler parameters to the vserver
+ configuration file. This method does not modify the kernel CPU
+ scheduling parameters for this context. """
if cpu_share == int(self.config.get("CPULIMIT", -1)):
return
- # XXX - don't want to have to deal with nm_ flags here
- cpu_guaranteed = int(self.resources.get("nm_sched_flags",
- None) == "guaranteed")
+ cpu_guaranteed = sched_flags & SCHED_CPU_GUARANTEED
cpu_config = { "CPULIMIT": cpu_share, "CPUGUARANTEED": cpu_guaranteed }
- self.__update_config_file(self.config_file, cpu_config)
+ self.update_resources(cpu_config)
if self.vm_running:
- # caller must ensure cpu_share is consistent with self.resources
- vserverimpl.setsched(self.ctx, self.resources)
+ 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
ret = vserverimpl.getrlimit(self.ctx,6)
return ret
- def set_bwlimit(self, share, minrate = 1, maxrate = None, dev = "eth0"):
+ def set_bwlimit(self, minrate = bwlimit.bwmin, maxrate = None,
+ exempt_min = None, exempt_max = None,
+ share = None, dev = "eth0"):
- if share:
- bwlimit.on(self.ctx, dev, share, minrate, maxrate)
- else:
+ 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, eth):
- # not implemented yet
- bwlimit = -1
- cap = "unknown"
- minrate = "unknown"
- maxrate = "unknown"
- return (bwlimit, cap, minrate, maxrate)
-
- def open(self, filename, mode = "r", bufsize = -1):
-
- (sendsock, recvsock) = passfdimpl.socketpair()
- child_pid = os.fork()
- if child_pid == 0:
- 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)
-
- # parent process
+ def get_bwlimit(self, dev = "eth0"):
- # XXX - need this since a lambda can't raise an exception
- def __throw(ex):
- raise ex
+ result = bwlimit.get(self.ctx)
+ # result of bwlimit.get is (ctx, share, minrate, maxrate)
+ if result:
+ result = result[1:]
+ return result
- 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)
- except OSError, ex:
- if ex.errno != errno.EAGAIN:
- throw = lambda : __throw(ex)
- fd = 0
- os.close(recvsock)
- if not fd:
- throw()
+ def open(self, filename, mode = "r", bufsize = -1):
- return os.fdopen(fd, mode, bufsize)
+ return self.chroot_call(open, filename, mode, bufsize)
def __do_chcontext(self, state_file):
print >>state_file, "S_PROFILE="
state_file.close()
- vserverimpl.chcontext(self.ctx, self.resources)
+ if vserverimpl.chcontext(self.ctx):
+ self.set_resources()
+ vserverimpl.setup_done(self.ctx)
def __prep(self, runlevel, log):
# perform pre-init cleanup
self.__prep(runlevel, log)
- # execute each init script in turn
- # XXX - we don't support all scripts that vserver script does
- cmd_pid = 0
- first_child = True
- 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 + [None]:
+ 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_WAIT,cmd[0],*cmd_args)
+ except:
+ traceback.print_exc()
+ os._exit(1)
+ state_file = None
# 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 update_resources(self, resources):
self.config.update(resources)
vserverimpl.killall(self.ctx, signal)
self.vm_running = False
+
+
+
+def create(vm_name, static = False, ctor = VServer):
+
+ options = []
+ if static:
+ options += ['--static']
+ runcmd.run('vuseradd', options + [vm_name])
+ vm_id = pwd.getpwnam(vm_name)[2]
+
+ return ctor(vm_name, vm_id)
git://git.onelab.eu / util-vserver.git / blobdiff