import time
import traceback
-import linuxcaps
+import mountimpl
import passfdimpl
-import vserverimpl
-
-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)
+import utmp
+import vserverimpl, vduimpl
+import cpulimit, bwlimit
+
+
#
# these are the flags taken from the kernel linux/vserver/legacy.h
class VServer:
- INITSCRIPTS = [('/etc/rc.vinit', 'start'), ('/etc/rc.d/rc', '3')]
+ INITSCRIPTS = [('/etc/rc.vinit', 'start'),
+ ('/etc/rc.d/rc', '%(runlevel)d')]
- def __init__(self, name):
+ def __init__(self, name, vm_id, vm_running = False, resources = {}):
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"])
+ 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
+ self.config = {}
+ for config_file in ["/etc/vservers.conf", self.config_file]:
+ try:
+ self.config.update(self.__read_config_file(config_file))
+ except IOError, ex:
+ if ex.errno != errno.ENOENT:
+ raise
+ self.remove_caps = ~vserverimpl.CAP_SAFE;
+ self.ctx = vm_id
+ self.vm_running = vm_running
+ self.resources = resources
config_var_re = re.compile(r"^ *([A-Z_]+)=(.*)\n?$", re.MULTILINE)
config[key] = val.strip('"')
return config
+ def __update_config_file(self, filename, newvars):
+
+ # read old file, apply changes
+ f = open(filename, "r")
+ data = f.read()
+ f.close()
+ todo = newvars.copy()
+ changed = False
+ 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):]
+ changed = True
+ for (newkey, newval) in todo.items():
+ data += "%s=%s\n" % (newkey, newval)
+ changed = True
+
+ if not changed:
+ return
+
+ # write new file
+ newfile = filename + ".new"
+ f = open(newfile, "w")
+ 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)
+ os.rename(newfile, filename)
+
def __do_chroot(self):
- return os.chroot("%s/%s" % (VROOTDIR, self.name))
+ os.chroot(self.dir)
+ os.chdir("/")
+ def set_disklimit(self, block_limit):
+
+ # block_limit is in kB
+ if block_limit == 0:
+ vserverimpl.unsetdlimit(self.dir, self.ctx)
+ return
+
+ 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
+
+ vserverimpl.setdlimit(self.dir,
+ self.ctx,
+ block_usage,
+ block_limit,
+ inode_usage,
+ vserverimpl.DLIMIT_INF, # inode limit
+ 2) # %age reserved for root
+
+ def get_disklimit(self):
+
+ try:
+ blocksused, blocktotal, inodesused, inodestotal, reserved = \
+ vserverimpl.getdlimit(self.dir, self.ctx)
+ except OSError, ex:
+ if ex.errno != errno.ESRCH:
+ raise
+ # get here if no vserver disk limit has been set for xid
+ blocktotal = -1
+
+ return blocktotal
+
+ def set_sched(self, cpu_share):
+
+ if cpu_share == int(self.config.get("CPULIMIT", -1)):
+ return
+
+ self.__update_config_file(self.config_file, { "CPULIMIT": cpu_share })
+ if self.vm_running:
+ vserverimpl.setsched(self.ctx, self.resources)
+
+ def get_sched(self):
+ # have no way of querying scheduler right now on a per vserver basis
+ return (-1, False)
+
+ def set_memlimit(self, limit):
+ ret = vserverimpl.setrlimit(self.ctx,5,limit)
+ return ret
+
+ def get_memlimit(self):
+ ret = vserverimpl.getrlimit(self.ctx,5)
+ return ret
+
+ def set_tasklimit(self, limit):
+ ret = vserverimpl.setrlimit(self.ctx,6,limit)
+ return ret
+
+ def get_tasklimit(self):
+ ret = vserverimpl.getrlimit(self.ctx,6)
+ return ret
+
+ def set_bwlimit(self, share, minrate = 1, maxrate = None, dev = "eth0"):
+
+ if share:
+ bwlimit.on(self.ctx, dev, share, minrate, maxrate)
+ else:
+ bwlimit.off(self.ctx, dev)
+
+ 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()
return os.fdopen(fd, mode, bufsize)
- def enter(self):
+ def __do_chcontext(self, state_file):
- state_file = open("/var/run/vservers/%s.ctx" % self.name, "w")
- self.__do_chroot()
- vserverimpl.chcontext(self.ctx, self.remove_caps)
+ vserverimpl.chcontext(self.ctx, self.resources)
+
+ 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()
- def start(self):
+ def __prep(self, runlevel, log):
+
+ """ Perform all the crap that the vserver script does before
+ actually executing the startup scripts. """
+
+ # remove /var/run and /var/lock/subsys files
+ # but don't remove utmp from the top-level /var/run
+ RUNDIR = "/var/run"
+ LOCKDIR = "/var/lock/subsys"
+ filter_fn = lambda fs: filter(lambda f: f != 'utmp', fs)
+ garbage = reduce((lambda (out, ff), (dir, subdirs, files):
+ (out + map((dir + "/").__add__, ff(files)),
+ lambda fs: fs)),
+ list(os.walk(RUNDIR)),
+ ([], filter_fn))[0]
+ garbage += filter(os.path.isfile, map((LOCKDIR + "/").__add__,
+ os.listdir(LOCKDIR)))
+ for f in garbage:
+ os.unlink(f)
+
+ # set the initial runlevel
+ f = open(RUNDIR + "/utmp", "w")
+ utmp.set_runlevel(f, runlevel)
+ f.close()
+
+ # mount /proc and /dev/pts
+ self.__do_mount("none", "/proc", "proc")
+ # XXX - magic mount options
+ self.__do_mount("none", "/dev/pts", "devpts", 0, "gid=5,mode=0620")
+
+ def __do_mount(self, *mount_args):
+
+ try:
+ mountimpl.mount(*mount_args)
+ except OSError, ex:
+ if ex.errno == errno.EBUSY:
+ # assume already mounted
+ return
+ raise ex
+
+ def enter(self):
+
+ state_file = open("/var/run/vservers/%s.ctx" % self.name, "w")
+ self.__do_chroot()
+ self.__do_chcontext(state_file)
+
+ def start(self, wait, runlevel = 3):
+
+ self.vm_running = True
child_pid = os.fork()
if child_pid == 0:
# get a new session
os.setsid()
+ # open state file to record vserver info
+ state_file = open("/var/run/vservers/%s.ctx" % 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)
- log = self.open("/var/log/boot.log", "w", 0)
+ self.__do_chroot()
+ log = open("/var/log/boot.log", "w", 0)
os.dup2(1, 2)
+ # XXX - close all other fds
- # write same output that vserver script does
print >>log, ("%s: starting the virtual server %s" %
(time.asctime(time.gmtime()), self.name))
+ # 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]:
- # don't bother waiting for last command to terminate
- if cmd == None:
- os._exit(0)
-
- # wait for previous command to terminate
- if cmd_pid:
+ # 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.enter()
- print >>log, "executing '%s'" % " ".join(cmd)
- os.execl(cmd[0], *cmd)
- finally:
+ 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
# we get here due to an exception in the top-level child process
except Exception, ex:
# parent process
return child_pid
+
+ def update_resources(self, resources):
+
+ self.config.update(resources)
+
+ # write new values to configuration file
+ self.__update_config_file(self.config_file, resources)
+
+ def init_disk_info(self):
+
+ (self.disk_inodes, self.disk_blocks, size) = vduimpl.vdu(self.dir)
+
+ return size