Remove deprecated “QueryLocks” LUXI request

[ganeti-local] / lib / bdev.py

diff --git a/lib/bdev.py b/lib/bdev.py
index abedc90..9488826 100644 (file)
--- a/lib/bdev.py
+++ b/lib/bdev.py
@@ -1,7 +1,7 @@
 #
 #
 
 #
 #
 

-# Copyright (C) 2006, 2007 Google Inc.
+# Copyright (C) 2006, 2007, 2010, 2011 Google Inc.

 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

@@ -24,12 +24,68 @@
 import re
 import time
 import errno
 import re
 import time
 import errno

+import shlex
+import stat

 import pyparsing as pyp
 import pyparsing as pyp

+import os
+import logging

 
 from ganeti import utils
 
 from ganeti import utils

-from ganeti import logger

 from ganeti import errors
 from ganeti import constants
 from ganeti import errors
 from ganeti import constants

+from ganeti import objects
+from ganeti import compat
+from ganeti import netutils
+
+
+# Size of reads in _CanReadDevice
+_DEVICE_READ_SIZE = 128 * 1024
+
+
+def _IgnoreError(fn, *args, **kwargs):
+  """Executes the given function, ignoring BlockDeviceErrors.
+
+  This is used in order to simplify the execution of cleanup or
+  rollback functions.
+
+  @rtype: boolean
+  @return: True when fn didn't raise an exception, False otherwise
+
+  """
+  try:
+    fn(*args, **kwargs)
+    return True
+  except errors.BlockDeviceError, err:
+    logging.warning("Caught BlockDeviceError but ignoring: %s", str(err))
+    return False
+
+
+def _ThrowError(msg, *args):
+  """Log an error to the node daemon and the raise an exception.
+
+  @type msg: string
+  @param msg: the text of the exception
+  @raise errors.BlockDeviceError
+
+  """
+  if args:
+    msg = msg % args
+  logging.error(msg)
+  raise errors.BlockDeviceError(msg)
+
+
+def _CanReadDevice(path):
+  """Check if we can read from the given device.
+
+  This tries to read the first 128k of the device.
+
+  """
+  try:
+    utils.ReadFile(path, size=_DEVICE_READ_SIZE)
+    return True
+  except EnvironmentError:
+    logging.warning("Can't read from device %s", path, exc_info=True)
+    return False

 
 
 class BlockDev(object):
 
 
 class BlockDev(object):

@@ -42,21 +98,16 @@ class BlockDev(object):
     - online (=used, or ready for use)
 
   A device can also be online but read-only, however we are not using
     - online (=used, or ready for use)
 
   A device can also be online but read-only, however we are not using

-  the readonly state (MD and LV have it, if needed in the future)
-  and we are usually looking at this like at a stack, so it's easier
-  to conceptualise the transition from not-existing to online and back
+  the readonly state (LV has it, if needed in the future) and we are
+  usually looking at this like at a stack, so it's easier to
+  conceptualise the transition from not-existing to online and back

   like a linear one.
 
   The many different states of the device are due to the fact that we
   need to cover many device types:
     - logical volumes are created, lvchange -a y $lv, and used
   like a linear one.
 
   The many different states of the device are due to the fact that we
   need to cover many device types:
     - logical volumes are created, lvchange -a y $lv, and used

-    - md arrays are created or assembled and used

     - drbd devices are attached to a local disk/remote peer and made primary
 
     - drbd devices are attached to a local disk/remote peer and made primary
 

-  The status of the device can be examined by `GetStatus()`, which
-  returns a numerical value, depending on the position in the
-  transition stack of the device.
-

   A block device is identified by three items:
     - the /dev path of the device (dynamic)
     - a unique ID of the device (static)
   A block device is identified by three items:
     - the /dev path of the device (dynamic)
     - a unique ID of the device (static)

@@ -64,15 +115,13 @@ class BlockDev(object):
 
   Not all devices implement both the first two as distinct items. LVM
   logical volumes have their unique ID (the pair volume group, logical
 
   Not all devices implement both the first two as distinct items. LVM
   logical volumes have their unique ID (the pair volume group, logical

-  volume name) in a 1-to-1 relation to the dev path. For MD devices,
-  the /dev path is dynamic and the unique ID is the UUID generated at
-  array creation plus the slave list. For DRBD devices, the /dev path
-  is again dynamic and the unique id is the pair (host1, dev1),
-  (host2, dev2).
+  volume name) in a 1-to-1 relation to the dev path. For DRBD devices,
+  the /dev path is again dynamic and the unique id is the pair (host1,
+  dev1), (host2, dev2).

 
   You can get to a device in two ways:
     - creating the (real) device, which returns you
 
   You can get to a device in two ways:
     - creating the (real) device, which returns you

-      an attached instance (lvcreate, mdadm --create)
+      an attached instance (lvcreate)

     - attaching of a python instance to an existing (real) device
 
   The second point, the attachement to a device, is different
     - attaching of a python instance to an existing (real) device
 
   The second point, the attachement to a device, is different

@@ -82,52 +131,29 @@ class BlockDev(object):
   after assembly we'll have our correct major/minor.
 
   """
   after assembly we'll have our correct major/minor.
 
   """

-  STATUS_UNKNOWN = 0
-  STATUS_EXISTING = 1
-  STATUS_STANDBY = 2
-  STATUS_ONLINE = 3
-
-  STATUS_MAP = {
-    STATUS_UNKNOWN: "unknown",
-    STATUS_EXISTING: "existing",
-    STATUS_STANDBY: "ready for use",
-    STATUS_ONLINE: "online",
-    }
-
-  def __init__(self, unique_id, children):
+  def __init__(self, unique_id, children, size, params):

     self._children = children
     self.dev_path = None
     self.unique_id = unique_id
     self.major = None
     self.minor = None
     self._children = children
     self.dev_path = None
     self.unique_id = unique_id
     self.major = None
     self.minor = None

+    self.attached = False
+    self.size = size
+    self.params = params

 
   def Assemble(self):
     """Assemble the device from its components.
 
 
   def Assemble(self):
     """Assemble the device from its components.
 

-    If this is a plain block device (e.g. LVM) than assemble does
-    nothing, as the LVM has no children and we don't put logical
-    volumes offline.
-
-    One guarantee is that after the device has been assembled, it
-    knows its major/minor numbers. This allows other devices (usually
-    parents) to probe correctly for their children.
+    Implementations of this method by child classes must ensure that:
+      - after the device has been assembled, it knows its major/minor
+        numbers; this allows other devices (usually parents) to probe
+        correctly for their children
+      - calling this method on an existing, in-use device is safe
+      - if the device is already configured (and in an OK state),
+        this method is idempotent

 
     """
 
     """

-    status = True
-    for child in self._children:
-      if not isinstance(child, BlockDev):
-        raise TypeError("Invalid child passed of type '%s'" % type(child))
-      if not status:
-        break
-      status = status and child.Assemble()
-      if not status:
-        break
-      status = status and child.Open()
-
-    if not status:
-      for child in self._children:
-        child.Shutdown()
-    return status
+    pass

 
   def Attach(self):
     """Find a device which matches our config and attach to it.
 
   def Attach(self):
     """Find a device which matches our config and attach to it.

@@ -142,7 +168,7 @@ class BlockDev(object):
     raise NotImplementedError
 
   @classmethod
     raise NotImplementedError
 
   @classmethod

-  def Create(cls, unique_id, children, size):
+  def Create(cls, unique_id, children, size, params):

     """Create the device.
 
     If the device cannot be created, it will return None
     """Create the device.
 
     If the device cannot be created, it will return None

@@ -158,9 +184,9 @@ class BlockDev(object):
   def Remove(self):
     """Remove this device.
 
   def Remove(self):
     """Remove this device.
 

-    This makes sense only for some of the device types: LV and to a
-    lesser degree, md devices. Also note that if the device can't
-    attach, the removal can't be completed.
+    This makes sense only for some of the device types: LV and file
+    storage. Also note that if the device can't attach, the removal
+    can't be completed.

 
     """
     raise NotImplementedError
 
     """
     raise NotImplementedError

@@ -173,12 +199,6 @@ class BlockDev(object):
     """
     raise NotImplementedError
 
     """
     raise NotImplementedError
 

-  def GetStatus(self):
-    """Return the status of the device.
-
-    """
-    raise NotImplementedError
-

   def Open(self, force=False):
     """Make the device ready for use.
 
   def Open(self, force=False):
     """Make the device ready for use.
 

@@ -201,16 +221,36 @@ class BlockDev(object):
     """
     raise NotImplementedError
 
     """
     raise NotImplementedError
 

-  def SetSyncSpeed(self, speed):
-    """Adjust the sync speed of the mirror.
+  def SetSyncParams(self, params):
+    """Adjust the synchronization parameters of the mirror.
+
+    In case this is not a mirroring device, this is no-op.
+
+    @param params: dictionary of LD level disk parameters related to the
+    synchronization.
+    @rtype: list
+    @return: a list of error messages, emitted both by the current node and by
+    children. An empty list means no errors.
+
+    """
+    result = []
+    if self._children:
+      for child in self._children:
+        result.extend(child.SetSyncParams(params))
+    return result
+
+  def PauseResumeSync(self, pause):
+    """Pause/Resume the sync of the mirror.

 
     In case this is not a mirroring device, this is no-op.
 
 
     In case this is not a mirroring device, this is no-op.
 

+    @param pause: Whether to pause or resume
+

     """
     result = True
     if self._children:
       for child in self._children:
     """
     result = True
     if self._children:
       for child in self._children:

-        result = result and child.SetSyncSpeed(speed)
+        result = result and child.PauseResumeSync(pause)

     return result
 
   def GetSyncStatus(self):
     return result
 
   def GetSyncStatus(self):

@@ -219,19 +259,29 @@ class BlockDev(object):
     If this device is a mirroring device, this function returns the
     status of the mirror.
 
     If this device is a mirroring device, this function returns the
     status of the mirror.
 

-    Returns:
-     (sync_percent, estimated_time, is_degraded)
+    If sync_percent is None, it means the device is not syncing.

 
 

-    If sync_percent is None, it means all is ok

     If estimated_time is None, it means we can't estimate
     If estimated_time is None, it means we can't estimate

-    the time needed, otherwise it's the time left in seconds
+    the time needed, otherwise it's the time left in seconds.
+

     If is_degraded is True, it means the device is missing
     redundancy. This is usually a sign that something went wrong in
     the device setup, if sync_percent is None.
 
     If is_degraded is True, it means the device is missing
     redundancy. This is usually a sign that something went wrong in
     the device setup, if sync_percent is None.
 

-    """
-    return None, None, False
+    The ldisk parameter represents the degradation of the local
+    data. This is only valid for some devices, the rest will always
+    return False (not degraded).

 
 

+    @rtype: objects.BlockDevStatus
+
+    """
+    return objects.BlockDevStatus(dev_path=self.dev_path,
+                                  major=self.major,
+                                  minor=self.minor,
+                                  sync_percent=None,
+                                  estimated_time=None,
+                                  is_degraded=False,
+                                  ldisk_status=constants.LDS_OKAY)

 
   def CombinedSyncStatus(self):
     """Calculate the mirror status recursively for our children.
 
   def CombinedSyncStatus(self):
     """Calculate the mirror status recursively for our children.

@@ -240,22 +290,44 @@ class BlockDev(object):
     minimum percent and maximum time are calculated across our
     children.
 
     minimum percent and maximum time are calculated across our
     children.
 

+    @rtype: objects.BlockDevStatus
+

     """
     """

-    min_percent, max_time, is_degraded = self.GetSyncStatus()
+    status = self.GetSyncStatus()
+
+    min_percent = status.sync_percent
+    max_time = status.estimated_time
+    is_degraded = status.is_degraded
+    ldisk_status = status.ldisk_status
+

     if self._children:
       for child in self._children:
     if self._children:
       for child in self._children:

-        c_percent, c_time, c_degraded = child.GetSyncStatus()
+        child_status = child.GetSyncStatus()
+

         if min_percent is None:
         if min_percent is None:

-          min_percent = c_percent
-        elif c_percent is not None:
-          min_percent = min(min_percent, c_percent)
+          min_percent = child_status.sync_percent
+        elif child_status.sync_percent is not None:
+          min_percent = min(min_percent, child_status.sync_percent)
+

         if max_time is None:
         if max_time is None:

-          max_time = c_time
-        elif c_time is not None:
-          max_time = max(max_time, c_time)
-        is_degraded = is_degraded or c_degraded
-    return min_percent, max_time, is_degraded
+          max_time = child_status.estimated_time
+        elif child_status.estimated_time is not None:
+          max_time = max(max_time, child_status.estimated_time)
+
+        is_degraded = is_degraded or child_status.is_degraded

 
 

+        if ldisk_status is None:
+          ldisk_status = child_status.ldisk_status
+        elif child_status.ldisk_status is not None:
+          ldisk_status = max(ldisk_status, child_status.ldisk_status)
+
+    return objects.BlockDevStatus(dev_path=self.dev_path,
+                                  major=self.major,
+                                  minor=self.minor,
+                                  sync_percent=min_percent,
+                                  estimated_time=max_time,
+                                  is_degraded=is_degraded,
+                                  ldisk_status=ldisk_status)

 
   def SetInfo(self, text):
     """Update metadata with info text.
 
   def SetInfo(self, text):
     """Update metadata with info text.

@@ -266,6 +338,34 @@ class BlockDev(object):
     for child in self._children:
       child.SetInfo(text)
 
     for child in self._children:
       child.SetInfo(text)
 

+  def Grow(self, amount, dryrun):
+    """Grow the block device.
+
+    @type amount: integer
+    @param amount: the amount (in mebibytes) to grow with
+    @type dryrun: boolean
+    @param dryrun: whether to execute the operation in simulation mode
+        only, without actually increasing the size
+
+    """
+    raise NotImplementedError
+
+  def GetActualSize(self):
+    """Return the actual disk size.
+
+    @note: the device needs to be active when this is called
+
+    """
+    assert self.attached, "BlockDevice not attached in GetActualSize()"
+    result = utils.RunCmd(["blockdev", "--getsize64", self.dev_path])
+    if result.failed:
+      _ThrowError("blockdev failed (%s): %s",
+                  result.fail_reason, result.output)
+    try:
+      sz = int(result.output.strip())
+    except (ValueError, TypeError), err:
+      _ThrowError("Failed to parse blockdev output: %s", str(err))
+    return sz

 
   def __repr__(self):
     return ("<%s: unique_id: %s, children: %s, %s:%s, %s>" %
 
   def __repr__(self):
     return ("<%s: unique_id: %s, children: %s, %s:%s, %s>" %

@@ -277,92 +377,195 @@ class LogicalVolume(BlockDev):
   """Logical Volume block device.
 
   """
   """Logical Volume block device.
 
   """

-  def __init__(self, unique_id, children):
+  _VALID_NAME_RE = re.compile("^[a-zA-Z0-9+_.-]*$")
+  _INVALID_NAMES = frozenset([".", "..", "snapshot", "pvmove"])
+  _INVALID_SUBSTRINGS = frozenset(["_mlog", "_mimage"])
+
+  def __init__(self, unique_id, children, size, params):

     """Attaches to a LV device.
 
     The unique_id is a tuple (vg_name, lv_name)
 
     """
     """Attaches to a LV device.
 
     The unique_id is a tuple (vg_name, lv_name)
 
     """

-    super(LogicalVolume, self).__init__(unique_id, children)
+    super(LogicalVolume, self).__init__(unique_id, children, size, params)

     if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
       raise ValueError("Invalid configuration data %s" % str(unique_id))
     self._vg_name, self._lv_name = unique_id
     if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
       raise ValueError("Invalid configuration data %s" % str(unique_id))
     self._vg_name, self._lv_name = unique_id

-    self.dev_path = "/dev/%s/%s" % (self._vg_name, self._lv_name)
+    self._ValidateName(self._vg_name)
+    self._ValidateName(self._lv_name)
+    self.dev_path = utils.PathJoin("/dev", self._vg_name, self._lv_name)
+    self._degraded = True
+    self.major = self.minor = self.pe_size = self.stripe_count = None

     self.Attach()
 
   @classmethod
     self.Attach()
 
   @classmethod

-  def Create(cls, unique_id, children, size):
+  def Create(cls, unique_id, children, size, params):

     """Create a new logical volume.
 
     """
     if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
     """Create a new logical volume.
 
     """
     if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:

-      raise ValueError("Invalid configuration data %s" % str(unique_id))
+      raise errors.ProgrammerError("Invalid configuration data %s" %
+                                   str(unique_id))

     vg_name, lv_name = unique_id
     vg_name, lv_name = unique_id

-    pvs_info = cls.GetPVInfo(vg_name)
+    cls._ValidateName(vg_name)
+    cls._ValidateName(lv_name)
+    pvs_info = cls.GetPVInfo([vg_name])

     if not pvs_info:
     if not pvs_info:

-      raise errors.BlockDeviceError("Can't compute PV info for vg %s" %
-                                    vg_name)
+      _ThrowError("Can't compute PV info for vg %s", vg_name)

     pvs_info.sort()
     pvs_info.reverse()
 
     pvs_info.sort()
     pvs_info.reverse()
 

-    pvlist = [ pv[1] for pv in pvs_info ]
-    free_size = sum([ pv[0] for pv in pvs_info ])
+    pvlist = [pv[1] for pv in pvs_info]
+    if compat.any(":" in v for v in pvlist):
+      _ThrowError("Some of your PVs have the invalid character ':' in their"
+                  " name, this is not supported - please filter them out"
+                  " in lvm.conf using either 'filter' or 'preferred_names'")
+    free_size = sum([pv[0] for pv in pvs_info])
+    current_pvs = len(pvlist)
+    desired_stripes = params[constants.LDP_STRIPES]
+    stripes = min(current_pvs, desired_stripes)
+    if stripes < desired_stripes:
+      logging.warning("Could not use %d stripes for VG %s, as only %d PVs are"
+                      " available.", desired_stripes, vg_name, current_pvs)

 
     # The size constraint should have been checked from the master before
     # calling the create function.
     if free_size < size:
 
     # The size constraint should have been checked from the master before
     # calling the create function.
     if free_size < size:

-      raise errors.BlockDeviceError("Not enough free space: required %s,"
-                                    " available %s" % (size, free_size))
-    result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-n%s" % lv_name,
-                           vg_name] + pvlist)
+      _ThrowError("Not enough free space: required %s,"
+                  " available %s", size, free_size)
+    cmd = ["lvcreate", "-L%dm" % size, "-n%s" % lv_name]
+    # If the free space is not well distributed, we won't be able to
+    # create an optimally-striped volume; in that case, we want to try
+    # with N, N-1, ..., 2, and finally 1 (non-stripped) number of
+    # stripes
+    for stripes_arg in range(stripes, 0, -1):
+      result = utils.RunCmd(cmd + ["-i%d" % stripes_arg] + [vg_name] + pvlist)
+      if not result.failed:
+        break

     if result.failed:
     if result.failed:

-      raise errors.BlockDeviceError(result.fail_reason)
-    return LogicalVolume(unique_id, children)
+      _ThrowError("LV create failed (%s): %s",
+                  result.fail_reason, result.output)
+    return LogicalVolume(unique_id, children, size, params)

 
   @staticmethod
 
   @staticmethod

-  def GetPVInfo(vg_name):
+  def _GetVolumeInfo(lvm_cmd, fields):
+    """Returns LVM Volumen infos using lvm_cmd
+
+    @param lvm_cmd: Should be one of "pvs", "vgs" or "lvs"
+    @param fields: Fields to return
+    @return: A list of dicts each with the parsed fields
+
+    """
+    if not fields:
+      raise errors.ProgrammerError("No fields specified")
+
+    sep = "|"
+    cmd = [lvm_cmd, "--noheadings", "--nosuffix", "--units=m", "--unbuffered",
+           "--separator=%s" % sep, "-o%s" % ",".join(fields)]
+
+    result = utils.RunCmd(cmd)
+    if result.failed:
+      raise errors.CommandError("Can't get the volume information: %s - %s" %
+                                (result.fail_reason, result.output))
+
+    data = []
+    for line in result.stdout.splitlines():
+      splitted_fields = line.strip().split(sep)
+
+      if len(fields) != len(splitted_fields):
+        raise errors.CommandError("Can't parse %s output: line '%s'" %
+                                  (lvm_cmd, line))
+
+      data.append(splitted_fields)
+
+    return data
+
+  @classmethod
+  def GetPVInfo(cls, vg_names, filter_allocatable=True):

     """Get the free space info for PVs in a volume group.
 
     """Get the free space info for PVs in a volume group.
 

-    Args:
-      vg_name: the volume group name
+    @param vg_names: list of volume group names, if empty all will be returned
+    @param filter_allocatable: whether to skip over unallocatable PVs

 
 

-    Returns:
-      list of (free_space, name) with free_space in mebibytes
+    @rtype: list
+    @return: list of tuples (free_space, name) with free_space in mebibytes

 
     """
 
     """

-    command = ["pvs", "--noheadings", "--nosuffix", "--units=m",
-               "-opv_name,vg_name,pv_free,pv_attr", "--unbuffered",
-               "--separator=:"]
-    result = utils.RunCmd(command)
-    if result.failed:
-      logger.Error("Can't get the PV information: %s" % result.fail_reason)
+    try:
+      info = cls._GetVolumeInfo("pvs", ["pv_name", "vg_name", "pv_free",
+                                        "pv_attr"])
+    except errors.GenericError, err:
+      logging.error("Can't get PV information: %s", err)

       return None
       return None

+

     data = []
     data = []

-    for line in result.stdout.splitlines():
-      fields = line.strip().split(':')
-      if len(fields) != 4:
-        logger.Error("Can't parse pvs output: line '%s'" % line)
-        return None
-      # skip over pvs from another vg or ones which are not allocatable
-      if fields[1] != vg_name or fields[3][0] != 'a':
+    for pv_name, vg_name, pv_free, pv_attr in info:
+      # (possibly) skip over pvs which are not allocatable
+      if filter_allocatable and pv_attr[0] != "a":
+        continue
+      # (possibly) skip over pvs which are not in the right volume group(s)
+      if vg_names and vg_name not in vg_names:
+        continue
+      data.append((float(pv_free), pv_name, vg_name))
+
+    return data
+
+  @classmethod
+  def GetVGInfo(cls, vg_names, filter_readonly=True):
+    """Get the free space info for specific VGs.
+
+    @param vg_names: list of volume group names, if empty all will be returned
+    @param filter_readonly: whether to skip over readonly VGs
+
+    @rtype: list
+    @return: list of tuples (free_space, total_size, name) with free_space in
+             MiB
+
+    """
+    try:
+      info = cls._GetVolumeInfo("vgs", ["vg_name", "vg_free", "vg_attr",
+                                        "vg_size"])
+    except errors.GenericError, err:
+      logging.error("Can't get VG information: %s", err)
+      return None
+
+    data = []
+    for vg_name, vg_free, vg_attr, vg_size in info:
+      # (possibly) skip over vgs which are not writable
+      if filter_readonly and vg_attr[0] == "r":
+        continue
+      # (possibly) skip over vgs which are not in the right volume group(s)
+      if vg_names and vg_name not in vg_names:

         continue
         continue

-      data.append((float(fields[2]), fields[0]))
+      data.append((float(vg_free), float(vg_size), vg_name))

 
     return data
 
 
     return data
 

+  @classmethod
+  def _ValidateName(cls, name):
+    """Validates that a given name is valid as VG or LV name.
+
+    The list of valid characters and restricted names is taken out of
+    the lvm(8) manpage, with the simplification that we enforce both
+    VG and LV restrictions on the names.
+
+    """
+    if (not cls._VALID_NAME_RE.match(name) or
+        name in cls._INVALID_NAMES or
+        compat.any(substring in name for substring in cls._INVALID_SUBSTRINGS)):
+      _ThrowError("Invalid LVM name '%s'", name)
+

   def Remove(self):
     """Remove this logical volume.
 
     """
     if not self.minor and not self.Attach():
       # the LV does not exist
   def Remove(self):
     """Remove this logical volume.
 
     """
     if not self.minor and not self.Attach():
       # the LV does not exist

-      return True
+      return

     result = utils.RunCmd(["lvremove", "-f", "%s/%s" %
                            (self._vg_name, self._lv_name)])
     if result.failed:
     result = utils.RunCmd(["lvremove", "-f", "%s/%s" %
                            (self._vg_name, self._lv_name)])
     if result.failed:

-      logger.Error("Can't lvremove: %s" % result.fail_reason)
-
-    return not result.failed
+      _ThrowError("Can't lvremove: %s - %s", result.fail_reason, result.output)

 
   def Rename(self, new_id):
     """Rename this logical volume.
 
   def Rename(self, new_id):
     """Rename this logical volume.

@@ -377,42 +580,86 @@ class LogicalVolume(BlockDev):
                                    (self._vg_name, new_vg))
     result = utils.RunCmd(["lvrename", new_vg, self._lv_name, new_name])
     if result.failed:
                                    (self._vg_name, new_vg))
     result = utils.RunCmd(["lvrename", new_vg, self._lv_name, new_name])
     if result.failed:

-      raise errors.BlockDeviceError("Failed to rename the logical volume: %s" %
-                                    result.output)
+      _ThrowError("Failed to rename the logical volume: %s", result.output)

     self._lv_name = new_name
     self._lv_name = new_name

-    self.dev_path = "/dev/%s/%s" % (self._vg_name, self._lv_name)
-
+    self.dev_path = utils.PathJoin("/dev", self._vg_name, self._lv_name)

 
   def Attach(self):
     """Attach to an existing LV.
 
     This method will try to see if an existing and active LV exists
 
   def Attach(self):
     """Attach to an existing LV.
 
     This method will try to see if an existing and active LV exists

-    which matches the our name. If so, its major/minor will be
+    which matches our name. If so, its major/minor will be

     recorded.
 
     """
     recorded.
 
     """

-    result = utils.RunCmd(["lvdisplay", self.dev_path])
+    self.attached = False
+    result = utils.RunCmd(["lvs", "--noheadings", "--separator=,",
+                           "--units=m", "--nosuffix",
+                           "-olv_attr,lv_kernel_major,lv_kernel_minor,"
+                           "vg_extent_size,stripes", self.dev_path])

     if result.failed:
     if result.failed:

-      logger.Error("Can't find LV %s: %s" %
-                   (self.dev_path, result.fail_reason))
+      logging.error("Can't find LV %s: %s, %s",
+                    self.dev_path, result.fail_reason, result.output)

       return False
       return False

-    match = re.compile("^ *Block device *([0-9]+):([0-9]+).*$")
-    for line in result.stdout.splitlines():
-      match_result = match.match(line)
-      if match_result:
-        self.major = int(match_result.group(1))
-        self.minor = int(match_result.group(2))
-        return True
-    return False
+    # the output can (and will) have multiple lines for multi-segment
+    # LVs, as the 'stripes' parameter is a segment one, so we take
+    # only the last entry, which is the one we're interested in; note
+    # that with LVM2 anyway the 'stripes' value must be constant
+    # across segments, so this is a no-op actually
+    out = result.stdout.splitlines()
+    if not out: # totally empty result? splitlines() returns at least
+                # one line for any non-empty string
+      logging.error("Can't parse LVS output, no lines? Got '%s'", str(out))
+      return False
+    out = out[-1].strip().rstrip(",")
+    out = out.split(",")
+    if len(out) != 5:
+      logging.error("Can't parse LVS output, len(%s) != 5", str(out))
+      return False
+
+    status, major, minor, pe_size, stripes = out
+    if len(status) != 6:
+      logging.error("lvs lv_attr is not 6 characters (%s)", status)
+      return False
+
+    try:
+      major = int(major)
+      minor = int(minor)
+    except (TypeError, ValueError), err:
+      logging.error("lvs major/minor cannot be parsed: %s", str(err))
+
+    try:
+      pe_size = int(float(pe_size))
+    except (TypeError, ValueError), err:
+      logging.error("Can't parse vg extent size: %s", err)
+      return False
+
+    try:
+      stripes = int(stripes)
+    except (TypeError, ValueError), err:
+      logging.error("Can't parse the number of stripes: %s", err)
+      return False
+
+    self.major = major
+    self.minor = minor
+    self.pe_size = pe_size
+    self.stripe_count = stripes
+    self._degraded = status[0] == "v" # virtual volume, i.e. doesn't backing
+                                      # storage
+    self.attached = True
+    return True

 
   def Assemble(self):
     """Assemble the device.
 
 
   def Assemble(self):
     """Assemble the device.
 

-    This is a no-op for the LV device type. Eventually, we could
-    lvchange -ay here if we see that the LV is not active.
+    We always run `lvchange -ay` on the LV to ensure it's active before
+    use, as there were cases when xenvg was not active after boot
+    (also possibly after disk issues).

 
     """
 
     """

-    return True
+    result = utils.RunCmd(["lvchange", "-ay", self.dev_path])
+    if result.failed:
+      _ThrowError("Can't activate lv %s: %s", self.dev_path, result.output)

 
   def Shutdown(self):
     """Shutdown the device.
 
   def Shutdown(self):
     """Shutdown the device.

@@ -421,35 +668,42 @@ class LogicalVolume(BlockDev):
     volumes on shutdown.
 
     """
     volumes on shutdown.
 
     """

-    return True
+    pass
+
+  def GetSyncStatus(self):
+    """Returns the sync status of the device.

 
 

-  def GetStatus(self):
-    """Return the status of the device.
+    If this device is a mirroring device, this function returns the
+    status of the mirror.
+
+    For logical volumes, sync_percent and estimated_time are always
+    None (no recovery in progress, as we don't handle the mirrored LV
+    case). The is_degraded parameter is the inverse of the ldisk
+    parameter.
+
+    For the ldisk parameter, we check if the logical volume has the
+    'virtual' type, which means it's not backed by existing storage
+    anymore (read from it return I/O error). This happens after a
+    physical disk failure and subsequent 'vgreduce --removemissing' on
+    the volume group.

 
 

-    Logical volumes will can be in all four states, although we don't
-    deactivate (lvchange -an) them when shutdown, so STATUS_EXISTING
-    should not be seen for our devices.
+    The status was already read in Attach, so we just return it.
+
+    @rtype: objects.BlockDevStatus

 
     """
 
     """

-    result = utils.RunCmd(["lvs", "--noheadings", "-olv_attr", self.dev_path])
-    if result.failed:
-      logger.Error("Can't display lv: %s" % result.fail_reason)
-      return self.STATUS_UNKNOWN
-    out = result.stdout.strip()
-    # format: type/permissions/alloc/fixed_minor/state/open
-    if len(out) != 6:
-      return self.STATUS_UNKNOWN
-    #writable = (out[1] == "w")
-    active = (out[4] == "a")
-    online = (out[5] == "o")
-    if online:
-      retval = self.STATUS_ONLINE
-    elif active:
-      retval = self.STATUS_STANDBY
+    if self._degraded:
+      ldisk_status = constants.LDS_FAULTY

     else:
     else:

-      retval = self.STATUS_EXISTING
+      ldisk_status = constants.LDS_OKAY

 
 

-    return retval
+    return objects.BlockDevStatus(dev_path=self.dev_path,
+                                  major=self.major,
+                                  minor=self.minor,
+                                  sync_percent=None,
+                                  estimated_time=None,
+                                  is_degraded=self._degraded,
+                                  ldisk_status=ldisk_status)

 
   def Open(self, force=False):
     """Make the device ready for I/O.
 
   def Open(self, force=False):
     """Make the device ready for I/O.

@@ -457,7 +711,7 @@ class LogicalVolume(BlockDev):
     This is a no-op for the LV device type.
 
     """
     This is a no-op for the LV device type.
 
     """

-    return True
+    pass

 
   def Close(self):
     """Notifies that the device will no longer be used for I/O.
 
   def Close(self):
     """Notifies that the device will no longer be used for I/O.

@@ -465,36 +719,35 @@ class LogicalVolume(BlockDev):
     This is a no-op for the LV device type.
 
     """
     This is a no-op for the LV device type.
 
     """

-    return True
+    pass

 
   def Snapshot(self, size):
     """Create a snapshot copy of an lvm block device.
 
 
   def Snapshot(self, size):
     """Create a snapshot copy of an lvm block device.
 

+    @returns: tuple (vg, lv)
+

     """
     snap_name = self._lv_name + ".snap"
 
     # remove existing snapshot if found
     """
     snap_name = self._lv_name + ".snap"
 
     # remove existing snapshot if found

-    snap = LogicalVolume((self._vg_name, snap_name), None)
-    snap.Remove()
+    snap = LogicalVolume((self._vg_name, snap_name), None, size, self.params)
+    _IgnoreError(snap.Remove)

 
 

-    pvs_info = self.GetPVInfo(self._vg_name)
-    if not pvs_info:
-      raise errors.BlockDeviceError("Can't compute PV info for vg %s" %
-                                    self._vg_name)
-    pvs_info.sort()
-    pvs_info.reverse()
-    free_size, pv_name = pvs_info[0]
+    vg_info = self.GetVGInfo([self._vg_name])
+    if not vg_info:
+      _ThrowError("Can't compute VG info for vg %s", self._vg_name)
+    free_size, _, _ = vg_info[0]

     if free_size < size:
     if free_size < size:

-      raise errors.BlockDeviceError("Not enough free space: required %s,"
-                                    " available %s" % (size, free_size))
+      _ThrowError("Not enough free space: required %s,"
+                  " available %s", size, free_size)

 
     result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-s",
                            "-n%s" % snap_name, self.dev_path])
     if result.failed:
 
     result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-s",
                            "-n%s" % snap_name, self.dev_path])
     if result.failed:

-      raise errors.BlockDeviceError("command: %s error: %s" %
-                                    (result.cmd, result.fail_reason))
+      _ThrowError("command: %s error: %s - %s",
+                  result.cmd, result.fail_reason, result.output)

 
 

-    return snap_name
+    return (self._vg_name, snap_name)

 
   def SetInfo(self, text):
     """Update metadata with info text.
 
   def SetInfo(self, text):
     """Update metadata with info text.

@@ -503,8 +756,8 @@ class LogicalVolume(BlockDev):
     BlockDev.SetInfo(self, text)
 
     # Replace invalid characters
     BlockDev.SetInfo(self, text)
 
     # Replace invalid characters

-    text = re.sub('^[^A-Za-z0-9_+.]', '_', text)
-    text = re.sub('[^-A-Za-z0-9_+.]', '_', text)
+    text = re.sub("^[^A-Za-z0-9_+.]", "_", text)
+    text = re.sub("[^-A-Za-z0-9_+.]", "_", text)

 
     # Only up to 128 characters are allowed
     text = text[:128]
 
     # Only up to 128 characters are allowed
     text = text[:128]

@@ -512,650 +765,542 @@ class LogicalVolume(BlockDev):
     result = utils.RunCmd(["lvchange", "--addtag", text,
                            self.dev_path])
     if result.failed:
     result = utils.RunCmd(["lvchange", "--addtag", text,
                            self.dev_path])
     if result.failed:

-      raise errors.BlockDeviceError("Command: %s error: %s" %
-                                    (result.cmd, result.fail_reason))
-
-
-class MDRaid1(BlockDev):
-  """raid1 device implemented via md.
+      _ThrowError("Command: %s error: %s - %s", result.cmd, result.fail_reason,
+                  result.output)
+
+  def Grow(self, amount, dryrun):
+    """Grow the logical volume.
+
+    """
+    if self.pe_size is None or self.stripe_count is None:
+      if not self.Attach():
+        _ThrowError("Can't attach to LV during Grow()")
+    full_stripe_size = self.pe_size * self.stripe_count
+    rest = amount % full_stripe_size
+    if rest != 0:
+      amount += full_stripe_size - rest
+    cmd = ["lvextend", "-L", "+%dm" % amount]
+    if dryrun:
+      cmd.append("--test")
+    # we try multiple algorithms since the 'best' ones might not have
+    # space available in the right place, but later ones might (since
+    # they have less constraints); also note that only recent LVM
+    # supports 'cling'
+    for alloc_policy in "contiguous", "cling", "normal":
+      result = utils.RunCmd(cmd + ["--alloc", alloc_policy, self.dev_path])
+      if not result.failed:
+        return
+    _ThrowError("Can't grow LV %s: %s", self.dev_path, result.output)
+
+
+class DRBD8Status(object):
+  """A DRBD status representation class.
+
+  Note that this doesn't support unconfigured devices (cs:Unconfigured).

 
   """
 
   """

-  def __init__(self, unique_id, children):
-    super(MDRaid1, self).__init__(unique_id, children)
-    self.major = 9
-    self.Attach()
-
-  def Attach(self):
-    """Find an array which matches our config and attach to it.
-
-    This tries to find a MD array which has the same UUID as our own.
-
-    """
-    minor = self._FindMDByUUID(self.unique_id)
-    if minor is not None:
-      self._SetFromMinor(minor)
+  UNCONF_RE = re.compile(r"\s*[0-9]+:\s*cs:Unconfigured$")
+  LINE_RE = re.compile(r"\s*[0-9]+:\s*cs:(\S+)\s+(?:st|ro):([^/]+)/(\S+)"
+                       "\s+ds:([^/]+)/(\S+)\s+.*$")
+  SYNC_RE = re.compile(r"^.*\ssync'ed:\s*([0-9.]+)%.*"
+                       # Due to a bug in drbd in the kernel, introduced in
+                       # commit 4b0715f096 (still unfixed as of 2011-08-22)
+                       "(?:\s|M)"
+                       "finish: ([0-9]+):([0-9]+):([0-9]+)\s.*$")
+
+  CS_UNCONFIGURED = "Unconfigured"
+  CS_STANDALONE = "StandAlone"
+  CS_WFCONNECTION = "WFConnection"
+  CS_WFREPORTPARAMS = "WFReportParams"
+  CS_CONNECTED = "Connected"
+  CS_STARTINGSYNCS = "StartingSyncS"
+  CS_STARTINGSYNCT = "StartingSyncT"
+  CS_WFBITMAPS = "WFBitMapS"
+  CS_WFBITMAPT = "WFBitMapT"
+  CS_WFSYNCUUID = "WFSyncUUID"
+  CS_SYNCSOURCE = "SyncSource"
+  CS_SYNCTARGET = "SyncTarget"
+  CS_PAUSEDSYNCS = "PausedSyncS"
+  CS_PAUSEDSYNCT = "PausedSyncT"
+  CSET_SYNC = frozenset([
+    CS_WFREPORTPARAMS,
+    CS_STARTINGSYNCS,
+    CS_STARTINGSYNCT,
+    CS_WFBITMAPS,
+    CS_WFBITMAPT,
+    CS_WFSYNCUUID,
+    CS_SYNCSOURCE,
+    CS_SYNCTARGET,
+    CS_PAUSEDSYNCS,
+    CS_PAUSEDSYNCT,
+    ])
+
+  DS_DISKLESS = "Diskless"
+  DS_ATTACHING = "Attaching" # transient state
+  DS_FAILED = "Failed" # transient state, next: diskless
+  DS_NEGOTIATING = "Negotiating" # transient state
+  DS_INCONSISTENT = "Inconsistent" # while syncing or after creation
+  DS_OUTDATED = "Outdated"
+  DS_DUNKNOWN = "DUnknown" # shown for peer disk when not connected
+  DS_CONSISTENT = "Consistent"
+  DS_UPTODATE = "UpToDate" # normal state
+
+  RO_PRIMARY = "Primary"
+  RO_SECONDARY = "Secondary"
+  RO_UNKNOWN = "Unknown"
+
+  def __init__(self, procline):
+    u = self.UNCONF_RE.match(procline)
+    if u:
+      self.cstatus = self.CS_UNCONFIGURED
+      self.lrole = self.rrole = self.ldisk = self.rdisk = None
+    else:
+      m = self.LINE_RE.match(procline)
+      if not m:
+        raise errors.BlockDeviceError("Can't parse input data '%s'" % procline)
+      self.cstatus = m.group(1)
+      self.lrole = m.group(2)
+      self.rrole = m.group(3)
+      self.ldisk = m.group(4)
+      self.rdisk = m.group(5)
+
+    # end reading of data from the LINE_RE or UNCONF_RE
+
+    self.is_standalone = self.cstatus == self.CS_STANDALONE
+    self.is_wfconn = self.cstatus == self.CS_WFCONNECTION
+    self.is_connected = self.cstatus == self.CS_CONNECTED
+    self.is_primary = self.lrole == self.RO_PRIMARY
+    self.is_secondary = self.lrole == self.RO_SECONDARY
+    self.peer_primary = self.rrole == self.RO_PRIMARY
+    self.peer_secondary = self.rrole == self.RO_SECONDARY
+    self.both_primary = self.is_primary and self.peer_primary
+    self.both_secondary = self.is_secondary and self.peer_secondary
+
+    self.is_diskless = self.ldisk == self.DS_DISKLESS
+    self.is_disk_uptodate = self.ldisk == self.DS_UPTODATE
+
+    self.is_in_resync = self.cstatus in self.CSET_SYNC
+    self.is_in_use = self.cstatus != self.CS_UNCONFIGURED
+
+    m = self.SYNC_RE.match(procline)
+    if m:
+      self.sync_percent = float(m.group(1))
+      hours = int(m.group(2))
+      minutes = int(m.group(3))
+      seconds = int(m.group(4))
+      self.est_time = hours * 3600 + minutes * 60 + seconds

     else:
     else:

-      self.minor = None
-      self.dev_path = None
+      # we have (in this if branch) no percent information, but if
+      # we're resyncing we need to 'fake' a sync percent information,
+      # as this is how cmdlib determines if it makes sense to wait for
+      # resyncing or not
+      if self.is_in_resync:
+        self.sync_percent = 0
+      else:
+        self.sync_percent = None
+      self.est_time = None

 
 

-    return (minor is not None)

 
 

-  @staticmethod
-  def _GetUsedDevs():
-    """Compute the list of in-use MD devices.
+class BaseDRBD(BlockDev): # pylint: disable=W0223
+  """Base DRBD class.

 
 

-    It doesn't matter if the used device have other raid level, just
-    that they are in use.
+  This class contains a few bits of common functionality between the
+  0.7 and 8.x versions of DRBD.

 
 

-    """
-    mdstat = open("/proc/mdstat", "r")
-    data = mdstat.readlines()
-    mdstat.close()
+  """
+  _VERSION_RE = re.compile(r"^version: (\d+)\.(\d+)\.(\d+)(?:\.\d+)?"
+                           r" \(api:(\d+)/proto:(\d+)(?:-(\d+))?\)")
+  _VALID_LINE_RE = re.compile("^ *([0-9]+): cs:([^ ]+).*$")
+  _UNUSED_LINE_RE = re.compile("^ *([0-9]+): cs:Unconfigured$")

 
 

-    used_md = {}
-    valid_line = re.compile("^md([0-9]+) : .*$")
-    for line in data:
-      match = valid_line.match(line)
-      if match:
-        md_no = int(match.group(1))
-        used_md[md_no] = line
+  _DRBD_MAJOR = 147
+  _ST_UNCONFIGURED = "Unconfigured"
+  _ST_WFCONNECTION = "WFConnection"
+  _ST_CONNECTED = "Connected"

 
 

-    return used_md
+  _STATUS_FILE = "/proc/drbd"
+  _USERMODE_HELPER_FILE = "/sys/module/drbd/parameters/usermode_helper"

 
   @staticmethod
 
   @staticmethod

-  def _GetDevInfo(minor):
-    """Get info about a MD device.
-
-    Currently only uuid is returned.
+  def _GetProcData(filename=_STATUS_FILE):
+    """Return data from /proc/drbd.

 
     """
 
     """

-    result = utils.RunCmd(["mdadm", "-D", "/dev/md%d" % minor])
-    if result.failed:
-      logger.Error("Can't display md: %s" % result.fail_reason)
-      return None
-    retval = {}
-    for line in result.stdout.splitlines():
-      line = line.strip()
-      kv = line.split(" : ", 1)
-      if kv:
-        if kv[0] == "UUID":
-          retval["uuid"] = kv[1].split()[0]
-        elif kv[0] == "State":
-          retval["state"] = kv[1].split(", ")
-    return retval
+    try:
+      data = utils.ReadFile(filename).splitlines()
+    except EnvironmentError, err:
+      if err.errno == errno.ENOENT:
+        _ThrowError("The file %s cannot be opened, check if the module"
+                    " is loaded (%s)", filename, str(err))
+      else:
+        _ThrowError("Can't read the DRBD proc file %s: %s", filename, str(err))
+    if not data:
+      _ThrowError("Can't read any data from %s", filename)
+    return data

 
 

-  @staticmethod
-  def _FindUnusedMinor():
-    """Compute an unused MD minor.
+  @classmethod
+  def _MassageProcData(cls, data):
+    """Transform the output of _GetProdData into a nicer form.

 
 

-    This code assumes that there are 256 minors only.
+    @return: a dictionary of minor: joined lines from /proc/drbd
+        for that minor

 
     """
 
     """

-    used_md = MDRaid1._GetUsedDevs()
-    i = 0
-    while i < 256:
-      if i not in used_md:
-        break
-      i += 1
-    if i == 256:
-      logger.Error("Critical: Out of md minor numbers.")
-      raise errors.BlockDeviceError("Can't find a free MD minor")
-    return i
+    results = {}
+    old_minor = old_line = None
+    for line in data:
+      if not line: # completely empty lines, as can be returned by drbd8.0+
+        continue
+      lresult = cls._VALID_LINE_RE.match(line)
+      if lresult is not None:
+        if old_minor is not None:
+          results[old_minor] = old_line
+        old_minor = int(lresult.group(1))
+        old_line = line
+      else:
+        if old_minor is not None:
+          old_line += " " + line.strip()
+    # add last line
+    if old_minor is not None:
+      results[old_minor] = old_line
+    return results

 
   @classmethod
 
   @classmethod

-  def _FindMDByUUID(cls, uuid):
-    """Find the minor of an MD array with a given UUID.
+  def _GetVersion(cls, proc_data):
+    """Return the DRBD version.

 
 

-    """
-    md_list = cls._GetUsedDevs()
-    for minor in md_list:
-      info = cls._GetDevInfo(minor)
-      if info and info["uuid"] == uuid:
-        return minor
-    return None
+    This will return a dict with keys:
+      - k_major
+      - k_minor
+      - k_point
+      - api
+      - proto
+      - proto2 (only on drbd > 8.2.X)

 
 

-  @staticmethod
-  def _ZeroSuperblock(dev_path):
-    """Zero the possible locations for an MD superblock.
+    """
+    first_line = proc_data[0].strip()
+    version = cls._VERSION_RE.match(first_line)
+    if not version:
+      raise errors.BlockDeviceError("Can't parse DRBD version from '%s'" %
+                                    first_line)

 
 

-    The zero-ing can't be done via ``mdadm --zero-superblock`` as that
-    fails in versions 2.x with the same error code as non-writable
-    device.
+    values = version.groups()
+    retval = {"k_major": int(values[0]),
+              "k_minor": int(values[1]),
+              "k_point": int(values[2]),
+              "api": int(values[3]),
+              "proto": int(values[4]),
+             }
+    if values[5] is not None:
+      retval["proto2"] = values[5]

 
 

-    The superblocks are located at (negative values are relative to
-    the end of the block device):
-      - -128k to end for version 0.90 superblock
-      - -8k to -12k for version 1.0 superblock (included in the above)
-      - 0k to 4k for version 1.1 superblock
-      - 4k to 8k for version 1.2 superblock
+    return retval

 
 

-    To cover all situations, the zero-ing will be:
-      - 0k to 128k
-      - -128k to end
+  @staticmethod
+  def GetUsermodeHelper(filename=_USERMODE_HELPER_FILE):
+    """Returns DRBD usermode_helper currently set.

 
 

-    As such, the minimum device size must be 128k, otherwise we'll get
-    I/O errors.
+    """
+    try:
+      helper = utils.ReadFile(filename).splitlines()[0]
+    except EnvironmentError, err:
+      if err.errno == errno.ENOENT:
+        _ThrowError("The file %s cannot be opened, check if the module"
+                    " is loaded (%s)", filename, str(err))
+      else:
+        _ThrowError("Can't read DRBD helper file %s: %s", filename, str(err))
+    if not helper:
+      _ThrowError("Can't read any data from %s", filename)
+    return helper

 
 

-    Note that this function depends on the fact that one can open,
-    read and write block devices normally.
+  @staticmethod
+  def _DevPath(minor):
+    """Return the path to a drbd device for a given minor.

 
     """
 
     """

-    overwrite_size = 128 * 1024
-    empty_buf = '\0' * overwrite_size
-    fd = open(dev_path, "r+")
-    try:
-      fd.seek(0, 0)
-      p1 = fd.tell()
-      fd.write(empty_buf)
-      p2 = fd.tell()
-      logger.Debug("Zeroed %s from %d to %d" % (dev_path, p1, p2))
-      fd.seek(-overwrite_size, 2)
-      p1 = fd.tell()
-      fd.write(empty_buf)
-      p2 = fd.tell()
-      logger.Debug("Zeroed %s from %d to %d" % (dev_path, p1, p2))
-    finally:
-      fd.close()
+    return "/dev/drbd%d" % minor

 
   @classmethod
 
   @classmethod

-  def Create(cls, unique_id, children, size):
-    """Create a new MD raid1 array.
-
-    """
-    if not isinstance(children, (tuple, list)):
-      raise ValueError("Invalid setup data for MDRaid1 dev: %s" %
-                       str(children))
-    for i in children:
-      if not isinstance(i, BlockDev):
-        raise ValueError("Invalid member in MDRaid1 dev: %s" % type(i))
-    for i in children:
-      try:
-        cls._ZeroSuperblock(i.dev_path)
-      except EnvironmentError, err:
-        logger.Error("Can't zero superblock for %s: %s" %
-                     (i.dev_path, str(err)))
-        return None
-    minor = cls._FindUnusedMinor()
-    result = utils.RunCmd(["mdadm", "--create", "/dev/md%d" % minor,
-                           "--auto=yes", "--force", "-l1",
-                           "-n%d" % len(children)] +
-                          [dev.dev_path for dev in children])
-
-    if result.failed:
-      logger.Error("Can't create md: %s: %s" % (result.fail_reason,
-                                                result.output))
-      return None
-    info = cls._GetDevInfo(minor)
-    if not info or not "uuid" in info:
-      logger.Error("Wrong information returned from mdadm -D: %s" % str(info))
-      return None
-    return MDRaid1(info["uuid"], children)
+  def GetUsedDevs(cls):
+    """Compute the list of used DRBD devices.

 
 

-  def Remove(self):
-    """Stub remove function for MD RAID 1 arrays.
+    """
+    data = cls._GetProcData()

 
 

-    We don't remove the superblock right now. Mark a to do.
+    used_devs = {}
+    for line in data:
+      match = cls._VALID_LINE_RE.match(line)
+      if not match:
+        continue
+      minor = int(match.group(1))
+      state = match.group(2)
+      if state == cls._ST_UNCONFIGURED:
+        continue
+      used_devs[minor] = state, line

 
 

-    """
-    #TODO: maybe zero superblock on child devices?
-    return self.Shutdown()
+    return used_devs

 
 

-  def Rename(self, new_id):
-    """Rename a device.
+  def _SetFromMinor(self, minor):
+    """Set our parameters based on the given minor.

 
 

-    This is not supported for md raid1 devices.
+    This sets our minor variable and our dev_path.

 
     """
 
     """

-    raise errors.ProgrammerError("Can't rename a md raid1 device")
+    if minor is None:
+      self.minor = self.dev_path = None
+      self.attached = False
+    else:
+      self.minor = minor
+      self.dev_path = self._DevPath(minor)
+      self.attached = True

 
 

-  def AddChildren(self, devices):
-    """Add new member(s) to the md raid1.
+  @staticmethod
+  def _CheckMetaSize(meta_device):
+    """Check if the given meta device looks like a valid one.

 
 

-    """
-    if self.minor is None and not self.Attach():
-      raise errors.BlockDeviceError("Can't attach to device")
-
-    args = ["mdadm", "-a", self.dev_path]
-    for dev in devices:
-      if dev.dev_path is None:
-        raise errors.BlockDeviceError("Child '%s' is not initialised" % dev)
-      dev.Open()
-      args.append(dev.dev_path)
-    result = utils.RunCmd(args)
-    if result.failed:
-      raise errors.BlockDeviceError("Failed to add new device to array: %s" %
-                                    result.output)
-    new_len = len(self._children) + len(devices)
-    result = utils.RunCmd(["mdadm", "--grow", self.dev_path, "-n", new_len])
-    if result.failed:
-      raise errors.BlockDeviceError("Can't grow md array: %s" %
-                                    result.output)
-    self._children.extend(devices)
-
-  def RemoveChildren(self, devices):
-    """Remove member(s) from the md raid1.
-
-    """
-    if self.minor is None and not self.Attach():
-      raise errors.BlockDeviceError("Can't attach to device")
-    new_len = len(self._children) - len(devices)
-    if new_len < 1:
-      raise errors.BlockDeviceError("Can't reduce to less than one child")
-    args = ["mdadm", "-f", self.dev_path]
-    orig_devs = []
-    for dev in devices:
-      args.append(dev)
-      for c in self._children:
-        if c.dev_path == dev:
-          orig_devs.append(c)
-          break
-      else:
-        raise errors.BlockDeviceError("Can't find device '%s' for removal" %
-                                      dev)
-    result = utils.RunCmd(args)
-    if result.failed:
-      raise errors.BlockDeviceError("Failed to mark device(s) as failed: %s" %
-                                    result.output)
-
-    # it seems here we need a short delay for MD to update its
-    # superblocks
-    time.sleep(0.5)
-    args[1] = "-r"
-    result = utils.RunCmd(args)
-    if result.failed:
-      raise errors.BlockDeviceError("Failed to remove device(s) from array:"
-                                    " %s" % result.output)
-    result = utils.RunCmd(["mdadm", "--grow", "--force", self.dev_path,
-                           "-n", new_len])
-    if result.failed:
-      raise errors.BlockDeviceError("Can't shrink md array: %s" %
-                                    result.output)
-    for dev in orig_devs:
-      self._children.remove(dev)
-
-  def GetStatus(self):
-    """Return the status of the device.
-
-    """
-    self.Attach()
-    if self.minor is None:
-      retval = self.STATUS_UNKNOWN
-    else:
-      retval = self.STATUS_ONLINE
-    return retval
-
-  def _SetFromMinor(self, minor):
-    """Set our parameters based on the given minor.
-
-    This sets our minor variable and our dev_path.
-
-    """
-    self.minor = minor
-    self.dev_path = "/dev/md%d" % minor
-
-  def Assemble(self):
-    """Assemble the MD device.
-
-    At this point we should have:
-      - list of children devices
-      - uuid
-
-    """
-    result = super(MDRaid1, self).Assemble()
-    if not result:
-      return result
-    md_list = self._GetUsedDevs()
-    for minor in md_list:
-      info = self._GetDevInfo(minor)
-      if info and info["uuid"] == self.unique_id:
-        self._SetFromMinor(minor)
-        logger.Info("MD array %s already started" % str(self))
-        return True
-    free_minor = self._FindUnusedMinor()
-    result = utils.RunCmd(["mdadm", "-A", "--auto=yes", "--uuid",
-                           self.unique_id, "/dev/md%d" % free_minor] +
-                          [bdev.dev_path for bdev in self._children])
-    if result.failed:
-      logger.Error("Can't assemble MD array: %s: %s" %
-                   (result.fail_reason, result.output))
-      self.minor = None
-    else:
-      self.minor = free_minor
-    return not result.failed
-
-  def Shutdown(self):
-    """Tear down the MD array.
-
-    This does a 'mdadm --stop' so after this command, the array is no
-    longer available.
+    This currently only check the size, which must be around
+    128MiB.

 
     """
 
     """

-    if self.minor is None and not self.Attach():
-      logger.Info("MD object not attached to a device")
-      return True
-
-    result = utils.RunCmd(["mdadm", "--stop", "/dev/md%d" % self.minor])
+    result = utils.RunCmd(["blockdev", "--getsize", meta_device])

     if result.failed:
     if result.failed:

-      logger.Error("Can't stop MD array: %s" % result.fail_reason)
-      return False
-    self.minor = None
-    self.dev_path = None
-    return True
-
-  def SetSyncSpeed(self, kbytes):
-    """Set the maximum sync speed for the MD array.
-
-    """
-    result = super(MDRaid1, self).SetSyncSpeed(kbytes)
-    if self.minor is None:
-      logger.Error("MD array not attached to a device")
-      return False
-    f = open("/sys/block/md%d/md/sync_speed_max" % self.minor, "w")
-    try:
-      f.write("%d" % kbytes)
-    finally:
-      f.close()
-    f = open("/sys/block/md%d/md/sync_speed_min" % self.minor, "w")
+      _ThrowError("Failed to get device size: %s - %s",
+                  result.fail_reason, result.output)

     try:
     try:

-      f.write("%d" % (kbytes/2))
-    finally:
-      f.close()
-    return result
-
-  def GetSyncStatus(self):
-    """Returns the sync status of the device.
-
-    Returns:
-     (sync_percent, estimated_time, is_degraded)
-
-    If sync_percent is None, it means all is ok
-    If estimated_time is None, it means we can't esimate
-    the time needed, otherwise it's the time left in seconds
-
-    """
-    if self.minor is None and not self.Attach():
-      raise errors.BlockDeviceError("Can't attach to device in GetSyncStatus")
-    dev_info = self._GetDevInfo(self.minor)
-    is_clean = ("state" in dev_info and
-                len(dev_info["state"]) == 1 and
-                dev_info["state"][0] in ("clean", "active"))
-    sys_path = "/sys/block/md%s/md/" % self.minor
-    f = file(sys_path + "sync_action")
-    sync_status = f.readline().strip()
-    f.close()
-    if sync_status == "idle":
-      return None, None, not is_clean
-    f = file(sys_path + "sync_completed")
-    sync_completed = f.readline().strip().split(" / ")
-    f.close()
-    if len(sync_completed) != 2:
-      return 0, None, not is_clean
-    sync_done, sync_total = [float(i) for i in sync_completed]
-    sync_percent = 100.0*sync_done/sync_total
-    f = file(sys_path + "sync_speed")
-    sync_speed_k = int(f.readline().strip())
-    if sync_speed_k == 0:
-      time_est = None
-    else:
-      time_est = (sync_total - sync_done) / 2 / sync_speed_k
-    return sync_percent, time_est, not is_clean
+      sectors = int(result.stdout)
+    except (TypeError, ValueError):
+      _ThrowError("Invalid output from blockdev: '%s'", result.stdout)
+    num_bytes = sectors * 512
+    if num_bytes < 128 * 1024 * 1024: # less than 128MiB
+      _ThrowError("Meta device too small (%.2fMib)", (num_bytes / 1024 / 1024))
+    # the maximum *valid* size of the meta device when living on top
+    # of LVM is hard to compute: it depends on the number of stripes
+    # and the PE size; e.g. a 2-stripe, 64MB PE will result in a 128MB
+    # (normal size), but an eight-stripe 128MB PE will result in a 1GB
+    # size meta device; as such, we restrict it to 1GB (a little bit
+    # too generous, but making assumptions about PE size is hard)
+    if num_bytes > 1024 * 1024 * 1024:
+      _ThrowError("Meta device too big (%.2fMiB)", (num_bytes / 1024 / 1024))

 
 

-  def Open(self, force=False):
-    """Make the device ready for I/O.
+  def Rename(self, new_id):
+    """Rename a device.

 
 

-    This is a no-op for the MDRaid1 device type, although we could use
-    the 2.6.18's new array_state thing.
+    This is not supported for drbd devices.

 
     """
 
     """

-    return True
-
-  def Close(self):
-    """Notifies that the device will no longer be used for I/O.
-
-    This is a no-op for the MDRaid1 device type, but see comment for
-    `Open()`.
+    raise errors.ProgrammerError("Can't rename a drbd device")

 
 

-    """
-    return True

 
 

+class DRBD8(BaseDRBD):
+  """DRBD v8.x block device.

 
 

-class BaseDRBD(BlockDev):
-  """Base DRBD class.
+  This implements the local host part of the DRBD device, i.e. it
+  doesn't do anything to the supposed peer. If you need a fully
+  connected DRBD pair, you need to use this class on both hosts.

 
 

-  This class contains a few bits of common functionality between the
-  0.7 and 8.x versions of DRBD.
+  The unique_id for the drbd device is the (local_ip, local_port,
+  remote_ip, remote_port) tuple, and it must have two children: the
+  data device and the meta_device. The meta device is checked for
+  valid size and is zeroed on create.

 
   """
 
   """

-  _VERSION_RE = re.compile(r"^version: (\d+)\.(\d+)\.(\d+)"
-                           r" \(api:(\d+)/proto:(\d+)\)")
-  _DRBD_MAJOR = 147
-  _ST_UNCONFIGURED = "Unconfigured"
-  _ST_WFCONNECTION = "WFConnection"
-  _ST_CONNECTED = "Connected"
-
-  @staticmethod
-  def _GetProcData():
-    """Return data from /proc/drbd.
-
-    """
-    stat = open("/proc/drbd", "r")
-    try:
-      data = stat.read().splitlines()
-    finally:
-      stat.close()
-    if not data:
-      raise errors.BlockDeviceError("Can't read any data from /proc/drbd")
-    return data
+  _MAX_MINORS = 255
+  _PARSE_SHOW = None

 
 

-  @staticmethod
-  def _MassageProcData(data):
-    """Transform the output of _GetProdData into a nicer form.
+  # timeout constants
+  _NET_RECONFIG_TIMEOUT = 60

 
 

-    Returns:
-      a dictionary of minor: joined lines from /proc/drbd for that minor
+  # command line options for barriers
+  _DISABLE_DISK_OPTION = "--no-disk-barrier"  # -a
+  _DISABLE_DRAIN_OPTION = "--no-disk-drain"   # -D
+  _DISABLE_FLUSH_OPTION = "--no-disk-flushes" # -i
+  _DISABLE_META_FLUSH_OPTION = "--no-md-flushes"  # -m

 
 

-    """
-    lmatch = re.compile("^ *([0-9]+):.*$")
-    results = {}
-    old_minor = old_line = None
-    for line in data:
-      lresult = lmatch.match(line)
-      if lresult is not None:
-        if old_minor is not None:
-          results[old_minor] = old_line
-        old_minor = int(lresult.group(1))
-        old_line = line
-      else:
-        if old_minor is not None:
-          old_line += " " + line.strip()
-    # add last line
-    if old_minor is not None:
-      results[old_minor] = old_line
-    return results
+  def __init__(self, unique_id, children, size, params):
+    if children and children.count(None) > 0:
+      children = []
+    if len(children) not in (0, 2):
+      raise ValueError("Invalid configuration data %s" % str(children))
+    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 6:
+      raise ValueError("Invalid configuration data %s" % str(unique_id))
+    (self._lhost, self._lport,
+     self._rhost, self._rport,
+     self._aminor, self._secret) = unique_id
+    if children:
+      if not _CanReadDevice(children[1].dev_path):
+        logging.info("drbd%s: Ignoring unreadable meta device", self._aminor)
+        children = []
+    super(DRBD8, self).__init__(unique_id, children, size, params)
+    self.major = self._DRBD_MAJOR
+    version = self._GetVersion(self._GetProcData())
+    if version["k_major"] != 8:
+      _ThrowError("Mismatch in DRBD kernel version and requested ganeti"
+                  " usage: kernel is %s.%s, ganeti wants 8.x",
+                  version["k_major"], version["k_minor"])
+
+    if (self._lhost is not None and self._lhost == self._rhost and
+        self._lport == self._rport):
+      raise ValueError("Invalid configuration data, same local/remote %s" %
+                       (unique_id,))
+    self.Attach()

 
   @classmethod
 
   @classmethod

-  def _GetVersion(cls):
-    """Return the DRBD version.
+  def _InitMeta(cls, minor, dev_path):
+    """Initialize a meta device.

 
 

-    This will return a list [k_major, k_minor, k_point, api, proto].
+    This will not work if the given minor is in use.

 
     """
 
     """

-    proc_data = cls._GetProcData()
-    first_line = proc_data[0].strip()
-    version = cls._VERSION_RE.match(first_line)
-    if not version:
-      raise errors.BlockDeviceError("Can't parse DRBD version from '%s'" %
-                                    first_line)
-    return [int(val) for val in version.groups()]
-
-  @staticmethod
-  def _DevPath(minor):
-    """Return the path to a drbd device for a given minor.
+    # Zero the metadata first, in order to make sure drbdmeta doesn't
+    # try to auto-detect existing filesystems or similar (see
+    # http://code.google.com/p/ganeti/issues/detail?id=182); we only
+    # care about the first 128MB of data in the device, even though it
+    # can be bigger
+    result = utils.RunCmd([constants.DD_CMD,
+                           "if=/dev/zero", "of=%s" % dev_path,
+                           "bs=1048576", "count=128", "oflag=direct"])
+    if result.failed:
+      _ThrowError("Can't wipe the meta device: %s", result.output)

 
 

-    """
-    return "/dev/drbd%d" % minor
+    result = utils.RunCmd(["drbdmeta", "--force", cls._DevPath(minor),
+                           "v08", dev_path, "0", "create-md"])
+    if result.failed:
+      _ThrowError("Can't initialize meta device: %s", result.output)

 
   @classmethod
 
   @classmethod

-  def _GetUsedDevs(cls):
-    """Compute the list of used DRBD devices.
+  def _FindUnusedMinor(cls):
+    """Find an unused DRBD device.
+
+    This is specific to 8.x as the minors are allocated dynamically,
+    so non-existing numbers up to a max minor count are actually free.

 
     """
     data = cls._GetProcData()
 
 
     """
     data = cls._GetProcData()
 

-    used_devs = {}
-    valid_line = re.compile("^ *([0-9]+): cs:([^ ]+).*$")
+    highest = None

     for line in data:
     for line in data:

-      match = valid_line.match(line)
-      if not match:
-        continue
-      minor = int(match.group(1))
-      state = match.group(2)
-      if state == cls._ST_UNCONFIGURED:
-        continue
-      used_devs[minor] = state, line
-
-    return used_devs
-
-  def _SetFromMinor(self, minor):
-    """Set our parameters based on the given minor.
-
-    This sets our minor variable and our dev_path.
-
-    """
-    if minor is None:
-      self.minor = self.dev_path = None
-    else:
-      self.minor = minor
-      self.dev_path = self._DevPath(minor)
+      match = cls._UNUSED_LINE_RE.match(line)
+      if match:
+        return int(match.group(1))
+      match = cls._VALID_LINE_RE.match(line)
+      if match:
+        minor = int(match.group(1))
+        highest = max(highest, minor)
+    if highest is None: # there are no minors in use at all
+      return 0
+    if highest >= cls._MAX_MINORS:
+      logging.error("Error: no free drbd minors!")
+      raise errors.BlockDeviceError("Can't find a free DRBD minor")
+    return highest + 1

 
 

-  @staticmethod
-  def _CheckMetaSize(meta_device):
-    """Check if the given meta device looks like a valid one.
+  @classmethod
+  def _GetShowParser(cls):
+    """Return a parser for `drbd show` output.

 
 

-    This currently only check the size, which must be around
-    128MiB.
+    This will either create or return an already-create parser for the
+    output of the command `drbd show`.

 
     """
 
     """

-    result = utils.RunCmd(["blockdev", "--getsize", meta_device])
-    if result.failed:
-      logger.Error("Failed to get device size: %s" % result.fail_reason)
-      return False
-    try:
-      sectors = int(result.stdout)
-    except ValueError:
-      logger.Error("Invalid output from blockdev: '%s'" % result.stdout)
-      return False
-    bytes = sectors * 512
-    if bytes < 128 * 1024 * 1024: # less than 128MiB
-      logger.Error("Meta device too small (%.2fMib)" % (bytes / 1024 / 1024))
-      return False
-    if bytes > (128 + 32) * 1024 * 1024: # account for an extra (big) PE on LVM
-      logger.Error("Meta device too big (%.2fMiB)" % (bytes / 1024 / 1024))
-      return False
-    return True
+    if cls._PARSE_SHOW is not None:
+      return cls._PARSE_SHOW

 
 

-  def Rename(self, new_id):
-    """Rename a device.
+    # pyparsing setup
+    lbrace = pyp.Literal("{").suppress()
+    rbrace = pyp.Literal("}").suppress()
+    lbracket = pyp.Literal("[").suppress()
+    rbracket = pyp.Literal("]").suppress()
+    semi = pyp.Literal(";").suppress()
+    colon = pyp.Literal(":").suppress()
+    # this also converts the value to an int
+    number = pyp.Word(pyp.nums).setParseAction(lambda s, l, t: int(t[0]))

 
 

-    This is not supported for drbd devices.
+    comment = pyp.Literal("#") + pyp.Optional(pyp.restOfLine)
+    defa = pyp.Literal("_is_default").suppress()
+    dbl_quote = pyp.Literal('"').suppress()

 
 

-    """
-    raise errors.ProgrammerError("Can't rename a drbd device")
+    keyword = pyp.Word(pyp.alphanums + "-")

 
 

+    # value types
+    value = pyp.Word(pyp.alphanums + "_-/.:")
+    quoted = dbl_quote + pyp.CharsNotIn('"') + dbl_quote
+    ipv4_addr = (pyp.Optional(pyp.Literal("ipv4")).suppress() +
+                 pyp.Word(pyp.nums + ".") + colon + number)
+    ipv6_addr = (pyp.Optional(pyp.Literal("ipv6")).suppress() +
+                 pyp.Optional(lbracket) + pyp.Word(pyp.hexnums + ":") +
+                 pyp.Optional(rbracket) + colon + number)
+    # meta device, extended syntax
+    meta_value = ((value ^ quoted) + lbracket + number + rbracket)
+    # device name, extended syntax
+    device_value = pyp.Literal("minor").suppress() + number

 
 

-class DRBDev(BaseDRBD):
-  """DRBD block device.
+    # a statement
+    stmt = (~rbrace + keyword + ~lbrace +
+            pyp.Optional(ipv4_addr ^ ipv6_addr ^ value ^ quoted ^ meta_value ^
+                         device_value) +
+            pyp.Optional(defa) + semi +
+            pyp.Optional(pyp.restOfLine).suppress())

 
 

-  This implements the local host part of the DRBD device, i.e. it
-  doesn't do anything to the supposed peer. If you need a fully
-  connected DRBD pair, you need to use this class on both hosts.
+    # an entire section
+    section_name = pyp.Word(pyp.alphas + "_")
+    section = section_name + lbrace + pyp.ZeroOrMore(pyp.Group(stmt)) + rbrace

 
 

-  The unique_id for the drbd device is the (local_ip, local_port,
-  remote_ip, remote_port) tuple, and it must have two children: the
-  data device and the meta_device. The meta device is checked for
-  valid size and is zeroed on create.
+    bnf = pyp.ZeroOrMore(pyp.Group(section ^ stmt))
+    bnf.ignore(comment)

 
 

-  """
-  def __init__(self, unique_id, children):
-    super(DRBDev, self).__init__(unique_id, children)
-    self.major = self._DRBD_MAJOR
-    [kmaj, kmin, kfix, api, proto] = self._GetVersion()
-    if kmaj != 0 and kmin != 7:
-      raise errors.BlockDeviceError("Mismatch in DRBD kernel version and"
-                                    " requested ganeti usage: kernel is"
-                                    " %s.%s, ganeti wants 0.7" % (kmaj, kmin))
+    cls._PARSE_SHOW = bnf

 
 

-    if len(children) != 2:
-      raise ValueError("Invalid configuration data %s" % str(children))
-    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 4:
-      raise ValueError("Invalid configuration data %s" % str(unique_id))
-    self._lhost, self._lport, self._rhost, self._rport = unique_id
-    self.Attach()
+    return bnf

 
   @classmethod
 
   @classmethod

-  def _FindUnusedMinor(cls):
-    """Find an unused DRBD device.
+  def _GetShowData(cls, minor):
+    """Return the `drbdsetup show` data for a minor.

 
     """
 
     """

-    data = cls._GetProcData()
-
-    valid_line = re.compile("^ *([0-9]+): cs:Unconfigured$")
-    for line in data:
-      match = valid_line.match(line)
-      if match:
-        return int(match.group(1))
-    logger.Error("Error: no free drbd minors!")
-    raise errors.BlockDeviceError("Can't find a free DRBD minor")
+    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "show"])
+    if result.failed:
+      logging.error("Can't display the drbd config: %s - %s",
+                    result.fail_reason, result.output)
+      return None
+    return result.stdout

 
   @classmethod
 
   @classmethod

-  def _GetDevInfo(cls, minor):
-    """Get details about a given DRBD minor.
+  def _GetDevInfo(cls, out):
+    """Parse details about a given DRBD minor.

 
 

-    This return, if available, the local backing device in (major,
-    minor) formant and the local and remote (ip, port) information.
+    This return, if available, the local backing device (as a path)
+    and the local and remote (ip, port) information from a string
+    containing the output of the `drbdsetup show` command as returned
+    by _GetShowData.

 
     """
     data = {}
 
     """
     data = {}

-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "show"])
-    if result.failed:
-      logger.Error("Can't display the drbd config: %s" % result.fail_reason)
-      return data
-    out = result.stdout
-    if out == "Not configured\n":
+    if not out:

       return data
       return data

-    for line in out.splitlines():
-      if "local_dev" not in data:
-        match = re.match("^Lower device: ([0-9]+):([0-9]+) .*$", line)
-        if match:
-          data["local_dev"] = (int(match.group(1)), int(match.group(2)))
-          continue
-      if "meta_dev" not in data:
-        match = re.match("^Meta device: (([0-9]+):([0-9]+)|internal).*$", line)
-        if match:
-          if match.group(2) is not None and match.group(3) is not None:
-            # matched on the major/minor
-            data["meta_dev"] = (int(match.group(2)), int(match.group(3)))
-          else:
-            # matched on the "internal" string
-            data["meta_dev"] = match.group(1)
-            # in this case, no meta_index is in the output
-            data["meta_index"] = -1
-          continue
-      if "meta_index" not in data:
-        match = re.match("^Meta index: ([0-9]+).*$", line)
-        if match:
-          data["meta_index"] = int(match.group(1))
-          continue
-      if "local_addr" not in data:
-        match = re.match("^Local address: ([0-9.]+):([0-9]+)$", line)
-        if match:
-          data["local_addr"] = (match.group(1), int(match.group(2)))
-          continue
-      if "remote_addr" not in data:
-        match = re.match("^Remote address: ([0-9.]+):([0-9]+)$", line)
-        if match:
-          data["remote_addr"] = (match.group(1), int(match.group(2)))
-          continue
+
+    bnf = cls._GetShowParser()
+    # run pyparse
+
+    try:
+      results = bnf.parseString(out)
+    except pyp.ParseException, err:
+      _ThrowError("Can't parse drbdsetup show output: %s", str(err))
+
+    # and massage the results into our desired format
+    for section in results:
+      sname = section[0]
+      if sname == "_this_host":
+        for lst in section[1:]:
+          if lst[0] == "disk":
+            data["local_dev"] = lst[1]
+          elif lst[0] == "meta-disk":
+            data["meta_dev"] = lst[1]
+            data["meta_index"] = lst[2]
+          elif lst[0] == "address":
+            data["local_addr"] = tuple(lst[1:])
+      elif sname == "_remote_host":
+        for lst in section[1:]:
+          if lst[0] == "address":
+            data["remote_addr"] = tuple(lst[1:])

     return data
 
   def _MatchesLocal(self, info):
     return data
 
   def _MatchesLocal(self, info):

@@ -1167,22 +1312,24 @@ class DRBDev(BaseDRBD):
     device.
 
     """
     device.
 
     """

-    if not ("local_dev" in info and "meta_dev" in info and
-            "meta_index" in info):
-      return False
+    if self._children:
+      backend, meta = self._children
+    else:
+      backend = meta = None

 
 

-    backend = self._children[0]

     if backend is not None:
     if backend is not None:

-      retval = (info["local_dev"] == (backend.major, backend.minor))
+      retval = ("local_dev" in info and info["local_dev"] == backend.dev_path)

     else:
     else:

-      retval = (info["local_dev"] == (0, 0))
-    meta = self._children[1]
+      retval = ("local_dev" not in info)
+

     if meta is not None:
     if meta is not None:

-      retval = retval and (info["meta_dev"] == (meta.major, meta.minor))
-      retval = retval and (info["meta_index"] == 0)
+      retval = retval and ("meta_dev" in info and
+                           info["meta_dev"] == meta.dev_path)
+      retval = retval and ("meta_index" in info and
+                           info["meta_index"] == 0)

     else:
     else:

-      retval = retval and (info["meta_dev"] == "internal" and
-                           info["meta_index"] == -1)
+      retval = retval and ("meta_dev" not in info and
+                           "meta_index" not in info)

     return retval
 
   def _MatchesNet(self, info):
     return retval
 
   def _MatchesNet(self, info):

@@ -1210,1033 +1357,1360 @@ class DRBDev(BaseDRBD):
               info["remote_addr"] == (self._rhost, self._rport))
     return retval
 
               info["remote_addr"] == (self._rhost, self._rport))
     return retval
 

-  @classmethod
-  def _AssembleLocal(cls, minor, backend, meta):
+  def _AssembleLocal(self, minor, backend, meta, size):

     """Configure the local part of a DRBD device.
 
     """Configure the local part of a DRBD device.
 

-    This is the first thing that must be done on an unconfigured DRBD
-    device. And it must be done only once.
-

     """
     """

-    if not cls._CheckMetaSize(meta):
-      return False
-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disk",
-                           backend, meta, "0", "-e", "detach"])
-    if result.failed:
-      logger.Error("Can't attach local disk: %s" % result.output)
-    return not result.failed
+    args = ["drbdsetup", self._DevPath(minor), "disk",
+            backend, meta, "0",
+            "-e", "detach",
+            "--create-device"]
+    if size:
+      args.extend(["-d", "%sm" % size])

 
 

-  @classmethod
-  def _ShutdownLocal(cls, minor):
-    """Detach from the local device.
+    version = self._GetVersion(self._GetProcData())
+    vmaj = version["k_major"]
+    vmin = version["k_minor"]
+    vrel = version["k_point"]

 
 

-    I/Os will continue to be served from the remote device. If we
-    don't have a remote device, this operation will fail.
+    barrier_args = \
+      self._ComputeDiskBarrierArgs(vmaj, vmin, vrel,
+                                   self.params[constants.LDP_BARRIERS],
+                                   self.params[constants.LDP_NO_META_FLUSH])
+    args.extend(barrier_args)

 
 

-    """
-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "detach"])
+    if self.params[constants.LDP_DISK_CUSTOM]:
+      args.extend(shlex.split(self.params[constants.LDP_DISK_CUSTOM]))
+
+    result = utils.RunCmd(args)

     if result.failed:
     if result.failed:

-      logger.Error("Can't detach local device: %s" % result.output)
-    return not result.failed
+      _ThrowError("drbd%d: can't attach local disk: %s", minor, result.output)

 
 

-  @staticmethod
-  def _ShutdownAll(minor):
-    """Deactivate the device.
+  @classmethod
+  def _ComputeDiskBarrierArgs(cls, vmaj, vmin, vrel, disabled_barriers,
+      disable_meta_flush):
+    """Compute the DRBD command line parameters for disk barriers

 
 

-    This will, of course, fail if the device is in use.
+    Returns a list of the disk barrier parameters as requested via the
+    disabled_barriers and disable_meta_flush arguments, and according to the
+    supported ones in the DRBD version vmaj.vmin.vrel
+
+    If the desired option is unsupported, raises errors.BlockDeviceError.

 
     """
 
     """

-    result = utils.RunCmd(["drbdsetup", DRBDev._DevPath(minor), "down"])
-    if result.failed:
-      logger.Error("Can't shutdown drbd device: %s" % result.output)
-    return not result.failed
+    disabled_barriers_set = frozenset(disabled_barriers)
+    if not disabled_barriers_set in constants.DRBD_VALID_BARRIER_OPT:
+      raise errors.BlockDeviceError("%s is not a valid option set for DRBD"
+                                    " barriers" % disabled_barriers)

 
 

-  @classmethod
-  def _AssembleNet(cls, minor, net_info, protocol):
-    """Configure the network part of the device.
+    args = []
+
+    # The following code assumes DRBD 8.x, with x < 4 and x != 1 (DRBD 8.1.x
+    # does not exist)
+    if not vmaj == 8 and vmin in (0, 2, 3):
+      raise errors.BlockDeviceError("Unsupported DRBD version: %d.%d.%d" %
+                                    (vmaj, vmin, vrel))

 
 

-    This operation can be, in theory, done multiple times, but there
-    have been cases (in lab testing) in which the network part of the
-    device had become stuck and couldn't be shut down because activity
-    from the new peer (also stuck) triggered a timer re-init and
-    needed remote peer interface shutdown in order to clear. So please
-    don't change online the net config.
+    def _AppendOrRaise(option, min_version):
+      """Helper for DRBD options"""
+      if min_version is not None and vrel >= min_version:
+        args.append(option)
+      else:
+        raise errors.BlockDeviceError("Could not use the option %s as the"
+                                      " DRBD version %d.%d.%d does not support"
+                                      " it." % (option, vmaj, vmin, vrel))
+
+    # the minimum version for each feature is encoded via pairs of (minor
+    # version -> x) where x is version in which support for the option was
+    # introduced.
+    meta_flush_supported = disk_flush_supported = {
+      0: 12,
+      2: 7,
+      3: 0,
+      }
+
+    disk_drain_supported = {
+      2: 7,
+      3: 0,
+      }
+
+    disk_barriers_supported = {
+      3: 0,
+      }
+
+    # meta flushes
+    if disable_meta_flush:
+      _AppendOrRaise(cls._DISABLE_META_FLUSH_OPTION,
+                     meta_flush_supported.get(vmin, None))
+
+    # disk flushes
+    if constants.DRBD_B_DISK_FLUSH in disabled_barriers_set:
+      _AppendOrRaise(cls._DISABLE_FLUSH_OPTION,
+                     disk_flush_supported.get(vmin, None))
+
+    # disk drain
+    if constants.DRBD_B_DISK_DRAIN in disabled_barriers_set:
+      _AppendOrRaise(cls._DISABLE_DRAIN_OPTION,
+                     disk_drain_supported.get(vmin, None))
+
+    # disk barriers
+    if constants.DRBD_B_DISK_BARRIERS in disabled_barriers_set:
+      _AppendOrRaise(cls._DISABLE_DISK_OPTION,
+                     disk_barriers_supported.get(vmin, None))
+
+    return args
+
+  def _AssembleNet(self, minor, net_info, protocol,
+                   dual_pri=False, hmac=None, secret=None):
+    """Configure the network part of the device.

 
     """
     lhost, lport, rhost, rport = net_info
 
     """
     lhost, lport, rhost, rport = net_info

-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "net",
-                           "%s:%s" % (lhost, lport), "%s:%s" % (rhost, rport),
-                           protocol])
+    if None in net_info:
+      # we don't want network connection and actually want to make
+      # sure its shutdown
+      self._ShutdownNet(minor)
+      return
+
+    # Workaround for a race condition. When DRBD is doing its dance to
+    # establish a connection with its peer, it also sends the
+    # synchronization speed over the wire. In some cases setting the
+    # sync speed only after setting up both sides can race with DRBD
+    # connecting, hence we set it here before telling DRBD anything
+    # about its peer.
+    sync_errors = self._SetMinorSyncParams(minor, self.params)
+    if sync_errors:
+      _ThrowError("drbd%d: can't set the synchronization parameters: %s" %
+                  (minor, utils.CommaJoin(sync_errors)))
+
+    if netutils.IP6Address.IsValid(lhost):
+      if not netutils.IP6Address.IsValid(rhost):
+        _ThrowError("drbd%d: can't connect ip %s to ip %s" %
+                    (minor, lhost, rhost))
+      family = "ipv6"
+    elif netutils.IP4Address.IsValid(lhost):
+      if not netutils.IP4Address.IsValid(rhost):
+        _ThrowError("drbd%d: can't connect ip %s to ip %s" %
+                    (minor, lhost, rhost))
+      family = "ipv4"
+    else:
+      _ThrowError("drbd%d: Invalid ip %s" % (minor, lhost))
+
+    args = ["drbdsetup", self._DevPath(minor), "net",
+            "%s:%s:%s" % (family, lhost, lport),
+            "%s:%s:%s" % (family, rhost, rport), protocol,
+            "-A", "discard-zero-changes",
+            "-B", "consensus",
+            "--create-device",
+            ]
+    if dual_pri:
+      args.append("-m")
+    if hmac and secret:
+      args.extend(["-a", hmac, "-x", secret])
+
+    if self.params[constants.LDP_NET_CUSTOM]:
+      args.extend(shlex.split(self.params[constants.LDP_NET_CUSTOM]))
+
+    result = utils.RunCmd(args)

     if result.failed:
     if result.failed:

-      logger.Error("Can't setup network for dbrd device: %s" %
-                   result.fail_reason)
-      return False
+      _ThrowError("drbd%d: can't setup network: %s - %s",
+                  minor, result.fail_reason, result.output)

 
 

-    timeout = time.time() + 10
-    ok = False
-    while time.time() < timeout:
-      info = cls._GetDevInfo(minor)
+    def _CheckNetworkConfig():
+      info = self._GetDevInfo(self._GetShowData(minor))

       if not "local_addr" in info or not "remote_addr" in info:
       if not "local_addr" in info or not "remote_addr" in info:

-        time.sleep(1)
-        continue
+        raise utils.RetryAgain()
+

       if (info["local_addr"] != (lhost, lport) or
           info["remote_addr"] != (rhost, rport)):
       if (info["local_addr"] != (lhost, lport) or
           info["remote_addr"] != (rhost, rport)):

-        time.sleep(1)
-        continue
-      ok = True
-      break
-    if not ok:
-      logger.Error("Timeout while configuring network")
-      return False
-    return True
+        raise utils.RetryAgain()
+
+    try:
+      utils.Retry(_CheckNetworkConfig, 1.0, 10.0)
+    except utils.RetryTimeout:
+      _ThrowError("drbd%d: timeout while configuring network", minor)
+
+  def AddChildren(self, devices):
+    """Add a disk to the DRBD device.
+
+    """
+    if self.minor is None:
+      _ThrowError("drbd%d: can't attach to dbrd8 during AddChildren",
+                  self._aminor)
+    if len(devices) != 2:
+      _ThrowError("drbd%d: need two devices for AddChildren", self.minor)
+    info = self._GetDevInfo(self._GetShowData(self.minor))
+    if "local_dev" in info:
+      _ThrowError("drbd%d: already attached to a local disk", self.minor)
+    backend, meta = devices
+    if backend.dev_path is None or meta.dev_path is None:
+      _ThrowError("drbd%d: children not ready during AddChildren", self.minor)
+    backend.Open()
+    meta.Open()
+    self._CheckMetaSize(meta.dev_path)
+    self._InitMeta(self._FindUnusedMinor(), meta.dev_path)
+
+    self._AssembleLocal(self.minor, backend.dev_path, meta.dev_path, self.size)
+    self._children = devices
+
+  def RemoveChildren(self, devices):
+    """Detach the drbd device from local storage.
+
+    """
+    if self.minor is None:
+      _ThrowError("drbd%d: can't attach to drbd8 during RemoveChildren",
+                  self._aminor)
+    # early return if we don't actually have backing storage
+    info = self._GetDevInfo(self._GetShowData(self.minor))
+    if "local_dev" not in info:
+      return
+    if len(self._children) != 2:
+      _ThrowError("drbd%d: we don't have two children: %s", self.minor,
+                  self._children)
+    if self._children.count(None) == 2: # we don't actually have children :)
+      logging.warning("drbd%d: requested detach while detached", self.minor)
+      return
+    if len(devices) != 2:
+      _ThrowError("drbd%d: we need two children in RemoveChildren", self.minor)
+    for child, dev in zip(self._children, devices):
+      if dev != child.dev_path:
+        _ThrowError("drbd%d: mismatch in local storage (%s != %s) in"
+                    " RemoveChildren", self.minor, dev, child.dev_path)
+
+    self._ShutdownLocal(self.minor)
+    self._children = []

 
   @classmethod
 
   @classmethod

-  def _ShutdownNet(cls, minor):
-    """Disconnect from the remote peer.
+  def _SetMinorSyncParams(cls, minor, params):
+    """Set the parameters of the DRBD syncer.
+
+    This is the low-level implementation.
+
+    @type minor: int
+    @param minor: the drbd minor whose settings we change
+    @type params: dict
+    @param params: LD level disk parameters related to the synchronization
+    @rtype: list
+    @return: a list of error messages
+
+    """
+
+    args = ["drbdsetup", cls._DevPath(minor), "syncer"]
+    if params[constants.LDP_DYNAMIC_RESYNC]:
+      version = cls._GetVersion(cls._GetProcData())
+      vmin = version["k_minor"]
+      vrel = version["k_point"]
+
+      # By definition we are using 8.x, so just check the rest of the version
+      # number
+      if vmin != 3 or vrel < 9:
+        msg = ("The current DRBD version (8.%d.%d) does not support the "
+               "dynamic resync speed controller" % (vmin, vrel))
+        logging.error(msg)
+        return [msg]
+
+      if params[constants.LDP_PLAN_AHEAD] == 0:
+        msg = ("A value of 0 for c-plan-ahead disables the dynamic sync speed"
+               " controller at DRBD level. If you want to disable it, please"
+               " set the dynamic-resync disk parameter to False.")
+        logging.error(msg)
+        return [msg]
+
+      # add the c-* parameters to args
+      args.extend(["--c-plan-ahead", params[constants.LDP_PLAN_AHEAD],
+                   "--c-fill-target", params[constants.LDP_FILL_TARGET],
+                   "--c-delay-target", params[constants.LDP_DELAY_TARGET],
+                   "--c-max-rate", params[constants.LDP_MAX_RATE],
+                   "--c-min-rate", params[constants.LDP_MIN_RATE],
+                  ])

 
 

-    This fails if we don't have a local device.
+    else:
+      args.extend(["-r", "%d" % params[constants.LDP_RESYNC_RATE]])
+
+    args.append("--create-device")
+    result = utils.RunCmd(args)
+    if result.failed:
+      msg = ("Can't change syncer rate: %s - %s" %
+             (result.fail_reason, result.output))
+      logging.error(msg)
+      return msg
+
+    return []
+
+  def SetSyncParams(self, params):
+    """Set the synchronization parameters of the DRBD syncer.
+
+    @type params: dict
+    @param params: LD level disk parameters related to the synchronization
+    @rtype: list
+    @return: a list of error messages, emitted both by the current node and by
+    children. An empty list means no errors

 
     """
 
     """

-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disconnect"])
-    logger.Error("Can't shutdown network: %s" % result.output)
-    return not result.failed
+    if self.minor is None:
+      err = "Not attached during SetSyncParams"
+      logging.info(err)
+      return [err]

 
 

-  def Assemble(self):
-    """Assemble the drbd.
+    children_result = super(DRBD8, self).SetSyncParams(params)
+    children_result.extend(self._SetMinorSyncParams(self.minor, params))
+    return children_result

 
 

-    Method:
-      - if we have a local backing device, we bind to it by:
-        - checking the list of used drbd devices
-        - check if the local minor use of any of them is our own device
-        - if yes, abort?
-        - if not, bind
-      - if we have a local/remote net info:
-        - redo the local backing device step for the remote device
-        - check if any drbd device is using the local port,
-          if yes abort
-        - check if any remote drbd device is using the remote
-          port, if yes abort (for now)
-        - bind our net port
-        - bind the remote net port
+  def PauseResumeSync(self, pause):
+    """Pauses or resumes the sync of a DRBD device.
+
+    @param pause: Wether to pause or resume
+    @return: the success of the operation

 
     """
 
     """

-    self.Attach()
-    if self.minor is not None:
-      logger.Info("Already assembled")
-      return True
+    if self.minor is None:
+      logging.info("Not attached during PauseSync")
+      return False

 
 

-    result = super(DRBDev, self).Assemble()
-    if not result:
-      return result
-
-    minor = self._FindUnusedMinor()
-    need_localdev_teardown = False
-    if self._children[0]:
-      result = self._AssembleLocal(minor, self._children[0].dev_path,
-                                   self._children[1].dev_path)
-      if not result:
-        return False
-      need_localdev_teardown = True
-    if self._lhost and self._lport and self._rhost and self._rport:
-      result = self._AssembleNet(minor,
-                                 (self._lhost, self._lport,
-                                  self._rhost, self._rport),
-                                 "C")
-      if not result:
-        if need_localdev_teardown:
-          # we will ignore failures from this
-          logger.Error("net setup failed, tearing down local device")
-          self._ShutdownAll(minor)
-        return False
-    self._SetFromMinor(minor)
-    return True
+    children_result = super(DRBD8, self).PauseResumeSync(pause)

 
 

-  def Shutdown(self):
-    """Shutdown the DRBD device.
+    if pause:
+      cmd = "pause-sync"
+    else:
+      cmd = "resume-sync"
+
+    result = utils.RunCmd(["drbdsetup", self.dev_path, cmd])
+    if result.failed:
+      logging.error("Can't %s: %s - %s", cmd,
+                    result.fail_reason, result.output)
+    return not result.failed and children_result
+
+  def GetProcStatus(self):
+    """Return device data from /proc.
+
+    """
+    if self.minor is None:
+      _ThrowError("drbd%d: GetStats() called while not attached", self._aminor)
+    proc_info = self._MassageProcData(self._GetProcData())
+    if self.minor not in proc_info:
+      _ThrowError("drbd%d: can't find myself in /proc", self.minor)
+    return DRBD8Status(proc_info[self.minor])
+
+  def GetSyncStatus(self):
+    """Returns the sync status of the device.
+
+
+    If sync_percent is None, it means all is ok
+    If estimated_time is None, it means we can't estimate
+    the time needed, otherwise it's the time left in seconds.
+
+
+    We set the is_degraded parameter to True on two conditions:
+    network not connected or local disk missing.
+
+    We compute the ldisk parameter based on whether we have a local
+    disk or not.
+
+    @rtype: objects.BlockDevStatus

 
     """
     if self.minor is None and not self.Attach():
 
     """
     if self.minor is None and not self.Attach():

-      logger.Info("DRBD device not attached to a device during Shutdown")
-      return True
-    if not self._ShutdownAll(self.minor):
+      _ThrowError("drbd%d: can't Attach() in GetSyncStatus", self._aminor)
+
+    stats = self.GetProcStatus()
+    is_degraded = not stats.is_connected or not stats.is_disk_uptodate
+
+    if stats.is_disk_uptodate:
+      ldisk_status = constants.LDS_OKAY
+    elif stats.is_diskless:
+      ldisk_status = constants.LDS_FAULTY
+    else:
+      ldisk_status = constants.LDS_UNKNOWN
+
+    return objects.BlockDevStatus(dev_path=self.dev_path,
+                                  major=self.major,
+                                  minor=self.minor,
+                                  sync_percent=stats.sync_percent,
+                                  estimated_time=stats.est_time,
+                                  is_degraded=is_degraded,
+                                  ldisk_status=ldisk_status)
+
+  def Open(self, force=False):
+    """Make the local state primary.
+
+    If the 'force' parameter is given, the '-o' option is passed to
+    drbdsetup. Since this is a potentially dangerous operation, the
+    force flag should be only given after creation, when it actually
+    is mandatory.
+
+    """
+    if self.minor is None and not self.Attach():
+      logging.error("DRBD cannot attach to a device during open")

       return False
       return False

-    self.minor = None
-    self.dev_path = None
-    return True
+    cmd = ["drbdsetup", self.dev_path, "primary"]
+    if force:
+      cmd.append("-o")
+    result = utils.RunCmd(cmd)
+    if result.failed:
+      _ThrowError("drbd%d: can't make drbd device primary: %s", self.minor,
+                  result.output)
+
+  def Close(self):
+    """Make the local state secondary.
+
+    This will, of course, fail if the device is in use.
+
+    """
+    if self.minor is None and not self.Attach():
+      _ThrowError("drbd%d: can't Attach() in Close()", self._aminor)
+    result = utils.RunCmd(["drbdsetup", self.dev_path, "secondary"])
+    if result.failed:
+      _ThrowError("drbd%d: can't switch drbd device to secondary: %s",
+                  self.minor, result.output)
+
+  def DisconnectNet(self):
+    """Removes network configuration.
+
+    This method shutdowns the network side of the device.
+
+    The method will wait up to a hardcoded timeout for the device to
+    go into standalone after the 'disconnect' command before
+    re-configuring it, as sometimes it takes a while for the
+    disconnect to actually propagate and thus we might issue a 'net'
+    command while the device is still connected. If the device will
+    still be attached to the network and we time out, we raise an
+    exception.
+
+    """
+    if self.minor is None:
+      _ThrowError("drbd%d: disk not attached in re-attach net", self._aminor)
+
+    if None in (self._lhost, self._lport, self._rhost, self._rport):
+      _ThrowError("drbd%d: DRBD disk missing network info in"
+                  " DisconnectNet()", self.minor)
+
+    class _DisconnectStatus:
+      def __init__(self, ever_disconnected):
+        self.ever_disconnected = ever_disconnected
+
+    dstatus = _DisconnectStatus(_IgnoreError(self._ShutdownNet, self.minor))
+
+    def _WaitForDisconnect():
+      if self.GetProcStatus().is_standalone:
+        return
+
+      # retry the disconnect, it seems possible that due to a well-time
+      # disconnect on the peer, my disconnect command might be ignored and
+      # forgotten
+      dstatus.ever_disconnected = \
+        _IgnoreError(self._ShutdownNet, self.minor) or dstatus.ever_disconnected
+
+      raise utils.RetryAgain()
+
+    # Keep start time
+    start_time = time.time()
+
+    try:
+      # Start delay at 100 milliseconds and grow up to 2 seconds
+      utils.Retry(_WaitForDisconnect, (0.1, 1.5, 2.0),
+                  self._NET_RECONFIG_TIMEOUT)
+    except utils.RetryTimeout:
+      if dstatus.ever_disconnected:
+        msg = ("drbd%d: device did not react to the"
+               " 'disconnect' command in a timely manner")
+      else:
+        msg = "drbd%d: can't shutdown network, even after multiple retries"
+
+      _ThrowError(msg, self.minor)
+
+    reconfig_time = time.time() - start_time
+    if reconfig_time > (self._NET_RECONFIG_TIMEOUT * 0.25):
+      logging.info("drbd%d: DisconnectNet: detach took %.3f seconds",
+                   self.minor, reconfig_time)
+
+  def AttachNet(self, multimaster):
+    """Reconnects the network.
+
+    This method connects the network side of the device with a
+    specified multi-master flag. The device needs to be 'Standalone'
+    but have valid network configuration data.
+
+    Args:
+      - multimaster: init the network in dual-primary mode
+
+    """
+    if self.minor is None:
+      _ThrowError("drbd%d: device not attached in AttachNet", self._aminor)
+
+    if None in (self._lhost, self._lport, self._rhost, self._rport):
+      _ThrowError("drbd%d: missing network info in AttachNet()", self.minor)
+
+    status = self.GetProcStatus()
+
+    if not status.is_standalone:
+      _ThrowError("drbd%d: device is not standalone in AttachNet", self.minor)
+
+    self._AssembleNet(self.minor,
+                      (self._lhost, self._lport, self._rhost, self._rport),
+                      constants.DRBD_NET_PROTOCOL, dual_pri=multimaster,
+                      hmac=constants.DRBD_HMAC_ALG, secret=self._secret)
+
+  def Attach(self):
+    """Check if our minor is configured.
+
+    This doesn't do any device configurations - it only checks if the
+    minor is in a state different from Unconfigured.
+
+    Note that this function will not change the state of the system in
+    any way (except in case of side-effects caused by reading from
+    /proc).
+
+    """
+    used_devs = self.GetUsedDevs()
+    if self._aminor in used_devs:
+      minor = self._aminor
+    else:
+      minor = None
+
+    self._SetFromMinor(minor)
+    return minor is not None
+
+  def Assemble(self):
+    """Assemble the drbd.
+
+    Method:
+      - if we have a configured device, we try to ensure that it matches
+        our config
+      - if not, we create it from zero
+      - anyway, set the device parameters
+
+    """
+    super(DRBD8, self).Assemble()
+
+    self.Attach()
+    if self.minor is None:
+      # local device completely unconfigured
+      self._FastAssemble()
+    else:
+      # we have to recheck the local and network status and try to fix
+      # the device
+      self._SlowAssemble()

 
 

-  def Attach(self):
-    """Find a DRBD device which matches our config and attach to it.
+    sync_errors = self.SetSyncParams(self.params)
+    if sync_errors:
+      _ThrowError("drbd%d: can't set the synchronization parameters: %s" %
+                  (self.minor, utils.CommaJoin(sync_errors)))
+
+  def _SlowAssemble(self):
+    """Assembles the DRBD device from a (partially) configured device.

 
     In case of partially attached (local device matches but no network
     setup), we perform the network attach. If successful, we re-test
     the attach if can return success.
 
     """
 
     In case of partially attached (local device matches but no network
     setup), we perform the network attach. If successful, we re-test
     the attach if can return success.
 
     """

-    for minor in self._GetUsedDevs():
-      info = self._GetDevInfo(minor)
+    # TODO: Rewrite to not use a for loop just because there is 'break'
+    # pylint: disable=W0631
+    net_data = (self._lhost, self._lport, self._rhost, self._rport)
+    for minor in (self._aminor,):
+      info = self._GetDevInfo(self._GetShowData(minor))

       match_l = self._MatchesLocal(info)
       match_r = self._MatchesNet(info)
       match_l = self._MatchesLocal(info)
       match_r = self._MatchesNet(info)

+

       if match_l and match_r:
       if match_l and match_r:

+        # everything matches

         break
         break

+

       if match_l and not match_r and "local_addr" not in info:
       if match_l and not match_r and "local_addr" not in info:

-        res_r = self._AssembleNet(minor,
-                                  (self._lhost, self._lport,
-                                   self._rhost, self._rport),
-                                  "C")
-        if res_r and self._MatchesNet(self._GetDevInfo(minor)):
+        # disk matches, but not attached to network, attach and recheck
+        self._AssembleNet(minor, net_data, constants.DRBD_NET_PROTOCOL,
+                          hmac=constants.DRBD_HMAC_ALG, secret=self._secret)
+        if self._MatchesNet(self._GetDevInfo(self._GetShowData(minor))):
+          break
+        else:
+          _ThrowError("drbd%d: network attach successful, but 'drbdsetup"
+                      " show' disagrees", minor)
+
+      if match_r and "local_dev" not in info:
+        # no local disk, but network attached and it matches
+        self._AssembleLocal(minor, self._children[0].dev_path,
+                            self._children[1].dev_path, self.size)
+        if self._MatchesNet(self._GetDevInfo(self._GetShowData(minor))):

           break
           break

+        else:
+          _ThrowError("drbd%d: disk attach successful, but 'drbdsetup"
+                      " show' disagrees", minor)
+
+      # this case must be considered only if we actually have local
+      # storage, i.e. not in diskless mode, because all diskless
+      # devices are equal from the point of view of local
+      # configuration
+      if (match_l and "local_dev" in info and
+          not match_r and "local_addr" in info):
+        # strange case - the device network part points to somewhere
+        # else, even though its local storage is ours; as we own the
+        # drbd space, we try to disconnect from the remote peer and
+        # reconnect to our correct one
+        try:
+          self._ShutdownNet(minor)
+        except errors.BlockDeviceError, err:
+          _ThrowError("drbd%d: device has correct local storage, wrong"
+                      " remote peer and is unable to disconnect in order"
+                      " to attach to the correct peer: %s", minor, str(err))
+        # note: _AssembleNet also handles the case when we don't want
+        # local storage (i.e. one or more of the _[lr](host|port) is
+        # None)
+        self._AssembleNet(minor, net_data, constants.DRBD_NET_PROTOCOL,
+                          hmac=constants.DRBD_HMAC_ALG, secret=self._secret)
+        if self._MatchesNet(self._GetDevInfo(self._GetShowData(minor))):
+          break
+        else:
+          _ThrowError("drbd%d: network attach successful, but 'drbdsetup"
+                      " show' disagrees", minor)
+

     else:
       minor = None
 
     self._SetFromMinor(minor)
     else:
       minor = None
 
     self._SetFromMinor(minor)

-    return minor is not None
+    if minor is None:
+      _ThrowError("drbd%d: cannot activate, unknown or unhandled reason",
+                  self._aminor)

 
 

-  def Open(self, force=False):
-    """Make the local state primary.
+  def _FastAssemble(self):
+    """Assemble the drbd device from zero.

 
 

-    If the 'force' parameter is given, the '--do-what-I-say' parameter
-    is given. Since this is a pottentialy dangerous operation, the
-    force flag should be only given after creation, when it actually
-    has to be given.
+    This is run when in Assemble we detect our minor is unused.

 
     """
 
     """

-    if self.minor is None and not self.Attach():
-      logger.Error("DRBD cannot attach to a device during open")
-      return False
-    cmd = ["drbdsetup", self.dev_path, "primary"]
-    if force:
-      cmd.append("--do-what-I-say")
-    result = utils.RunCmd(cmd)
-    if result.failed:
-      logger.Error("Can't make drbd device primary: %s" % result.output)
-      return False
-    return True
+    minor = self._aminor
+    if self._children and self._children[0] and self._children[1]:
+      self._AssembleLocal(minor, self._children[0].dev_path,
+                          self._children[1].dev_path, self.size)
+    if self._lhost and self._lport and self._rhost and self._rport:
+      self._AssembleNet(minor,
+                        (self._lhost, self._lport, self._rhost, self._rport),
+                        constants.DRBD_NET_PROTOCOL,
+                        hmac=constants.DRBD_HMAC_ALG, secret=self._secret)
+    self._SetFromMinor(minor)

 
 

-  def Close(self):
-    """Make the local state secondary.
+  @classmethod
+  def _ShutdownLocal(cls, minor):
+    """Detach from the local device.

 
 

-    This will, of course, fail if the device is in use.
+    I/Os will continue to be served from the remote device. If we
+    don't have a remote device, this operation will fail.

 
     """
 
     """

-    if self.minor is None and not self.Attach():
-      logger.Info("Instance not attached to a device")
-      raise errors.BlockDeviceError("Can't find device")
-    result = utils.RunCmd(["drbdsetup", self.dev_path, "secondary"])
+    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "detach"])

     if result.failed:
     if result.failed:

-      logger.Error("Can't switch drbd device to secondary: %s" % result.output)
-      raise errors.BlockDeviceError("Can't switch drbd device to secondary")
+      _ThrowError("drbd%d: can't detach local disk: %s", minor, result.output)
+
+  @classmethod
+  def _ShutdownNet(cls, minor):
+    """Disconnect from the remote peer.

 
 

-  def SetSyncSpeed(self, kbytes):
-    """Set the speed of the DRBD syncer.
+    This fails if we don't have a local device.

 
     """
 
     """

-    children_result = super(DRBDev, self).SetSyncSpeed(kbytes)
-    if self.minor is None:
-      logger.Info("Instance not attached to a device")
-      return False
-    result = utils.RunCmd(["drbdsetup", self.dev_path, "syncer", "-r", "%d" %
-                           kbytes])
+    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disconnect"])

     if result.failed:
     if result.failed:

-      logger.Error("Can't change syncer rate: %s " % result.fail_reason)
-    return not result.failed and children_result
+      _ThrowError("drbd%d: can't shutdown network: %s", minor, result.output)

 
 

-  def GetSyncStatus(self):
-    """Returns the sync status of the device.
-
-    Returns:
-     (sync_percent, estimated_time, is_degraded)
+  @classmethod
+  def _ShutdownAll(cls, minor):
+    """Deactivate the device.

 
 

-    If sync_percent is None, it means all is ok
-    If estimated_time is None, it means we can't esimate
-    the time needed, otherwise it's the time left in seconds
+    This will, of course, fail if the device is in use.

 
     """
 
     """

-    if self.minor is None and not self.Attach():
-      raise errors.BlockDeviceError("Can't attach to device in GetSyncStatus")
-    proc_info = self._MassageProcData(self._GetProcData())
-    if self.minor not in proc_info:
-      raise errors.BlockDeviceError("Can't find myself in /proc (minor %d)" %
-                                    self.minor)
-    line = proc_info[self.minor]
-    match = re.match("^.*sync'ed: *([0-9.]+)%.*"
-                     " finish: ([0-9]+):([0-9]+):([0-9]+) .*$", line)
-    if match:
-      sync_percent = float(match.group(1))
-      hours = int(match.group(2))
-      minutes = int(match.group(3))
-      seconds = int(match.group(4))
-      est_time = hours * 3600 + minutes * 60 + seconds
-    else:
-      sync_percent = None
-      est_time = None
-    match = re.match("^ *[0-9]+: cs:([^ ]+).*$", line)
-    if not match:
-      raise errors.BlockDeviceError("Can't find my data in /proc (minor %d)" %
-                                    self.minor)
-    client_state = match.group(1)
-    is_degraded = client_state != "Connected"
-    return sync_percent, est_time, is_degraded
-
-  def GetStatus(self):
-    """Compute the status of the DRBD device
+    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "down"])
+    if result.failed:
+      _ThrowError("drbd%d: can't shutdown drbd device: %s",
+                  minor, result.output)

 
 

-    Note that DRBD devices don't have the STATUS_EXISTING state.
+  def Shutdown(self):
+    """Shutdown the DRBD device.

 
     """
     if self.minor is None and not self.Attach():
 
     """
     if self.minor is None and not self.Attach():

-      return self.STATUS_UNKNOWN
-
-    data = self._GetProcData()
-    match = re.compile("^ *%d: cs:[^ ]+ st:(Primary|Secondary)/.*$" %
-                       self.minor)
-    for line in data:
-      mresult = match.match(line)
-      if mresult:
-        break
-    else:
-      logger.Error("Can't find myself!")
-      return self.STATUS_UNKNOWN
-
-    state = mresult.group(2)
-    if state == "Primary":
-      result = self.STATUS_ONLINE
-    else:
-      result = self.STATUS_STANDBY
-
-    return result
-
-  @staticmethod
-  def _ZeroDevice(device):
-    """Zero a device.
+      logging.info("drbd%d: not attached during Shutdown()", self._aminor)
+      return
+    minor = self.minor
+    self.minor = None
+    self.dev_path = None
+    self._ShutdownAll(minor)

 
 

-    This writes until we get ENOSPC.
+  def Remove(self):
+    """Stub remove for DRBD devices.

 
     """
 
     """

-    f = open(device, "w")
-    buf = "\0" * 1048576
-    try:
-      while True:
-        f.write(buf)
-    except IOError, err:
-      if err.errno != errno.ENOSPC:
-        raise
+    self.Shutdown()

 
   @classmethod
 
   @classmethod

-  def Create(cls, unique_id, children, size):
-    """Create a new DRBD device.
+  def Create(cls, unique_id, children, size, params):
+    """Create a new DRBD8 device.

 
     Since DRBD devices are not created per se, just assembled, this
 
     Since DRBD devices are not created per se, just assembled, this

-    function just zeroes the meta device.
+    function only initializes the metadata.

 
     """
     if len(children) != 2:
       raise errors.ProgrammerError("Invalid setup for the drbd device")
 
     """
     if len(children) != 2:
       raise errors.ProgrammerError("Invalid setup for the drbd device")

+    # check that the minor is unused
+    aminor = unique_id[4]
+    proc_info = cls._MassageProcData(cls._GetProcData())
+    if aminor in proc_info:
+      status = DRBD8Status(proc_info[aminor])
+      in_use = status.is_in_use
+    else:
+      in_use = False
+    if in_use:
+      _ThrowError("drbd%d: minor is already in use at Create() time", aminor)

     meta = children[1]
     meta.Assemble()
     if not meta.Attach():
     meta = children[1]
     meta.Assemble()
     if not meta.Attach():

-      raise errors.BlockDeviceError("Can't attach to meta device")
-    if not cls._CheckMetaSize(meta.dev_path):
-      raise errors.BlockDeviceError("Invalid meta device")
-    logger.Info("Started zeroing device %s" % meta.dev_path)
-    cls._ZeroDevice(meta.dev_path)
-    logger.Info("Done zeroing device %s" % meta.dev_path)
-    return cls(unique_id, children)
+      _ThrowError("drbd%d: can't attach to meta device '%s'",
+                  aminor, meta)
+    cls._CheckMetaSize(meta.dev_path)
+    cls._InitMeta(aminor, meta.dev_path)
+    return cls(unique_id, children, size, params)

 
 

-  def Remove(self):
-    """Stub remove for DRBD devices.
+  def Grow(self, amount, dryrun):
+    """Resize the DRBD device and its backing storage.

 
     """
 
     """

-    return self.Shutdown()
+    if self.minor is None:
+      _ThrowError("drbd%d: Grow called while not attached", self._aminor)
+    if len(self._children) != 2 or None in self._children:
+      _ThrowError("drbd%d: cannot grow diskless device", self.minor)
+    self._children[0].Grow(amount, dryrun)
+    if dryrun:
+      # DRBD does not support dry-run mode, so we'll return here
+      return
+    result = utils.RunCmd(["drbdsetup", self.dev_path, "resize", "-s",
+                           "%dm" % (self.size + amount)])
+    if result.failed:
+      _ThrowError("drbd%d: resize failed: %s", self.minor, result.output)

 
 
 
 

-class DRBD8(BaseDRBD):
-  """DRBD v8.x block device.
+class FileStorage(BlockDev):
+  """File device.

 
 

-  This implements the local host part of the DRBD device, i.e. it
-  doesn't do anything to the supposed peer. If you need a fully
-  connected DRBD pair, you need to use this class on both hosts.
+  This class represents the a file storage backend device.

 
 

-  The unique_id for the drbd device is the (local_ip, local_port,
-  remote_ip, remote_port) tuple, and it must have two children: the
-  data device and the meta_device. The meta device is checked for
-  valid size and is zeroed on create.
+  The unique_id for the file device is a (file_driver, file_path) tuple.

 
   """
 
   """

-  _MAX_MINORS = 255
-  _PARSE_SHOW = None
-
-  def __init__(self, unique_id, children):
-    if children and children.count(None) > 0:
-      children = []
-    super(DRBD8, self).__init__(unique_id, children)
-    self.major = self._DRBD_MAJOR
-    [kmaj, kmin, kfix, api, proto] = self._GetVersion()
-    if kmaj != 8:
-      raise errors.BlockDeviceError("Mismatch in DRBD kernel version and"
-                                    " requested ganeti usage: kernel is"
-                                    " %s.%s, ganeti wants 8.x" % (kmaj, kmin))
+  def __init__(self, unique_id, children, size, params):
+    """Initalizes a file device backend.

 
 

-    if len(children) not in (0, 2):
-      raise ValueError("Invalid configuration data %s" % str(children))
-    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 4:
+    """
+    if children:
+      raise errors.BlockDeviceError("Invalid setup for file device")
+    super(FileStorage, self).__init__(unique_id, children, size, params)
+    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:

       raise ValueError("Invalid configuration data %s" % str(unique_id))
       raise ValueError("Invalid configuration data %s" % str(unique_id))

-    self._lhost, self._lport, self._rhost, self._rport = unique_id
+    self.driver = unique_id[0]
+    self.dev_path = unique_id[1]

     self.Attach()
 
     self.Attach()
 

-  @classmethod
-  def _InitMeta(cls, minor, dev_path):
-    """Initialize a meta device.
+  def Assemble(self):
+    """Assemble the device.

 
 

-    This will not work if the given minor is in use.
+    Checks whether the file device exists, raises BlockDeviceError otherwise.

 
     """
 
     """

-    result = utils.RunCmd(["drbdmeta", "--force", cls._DevPath(minor),
-                           "v08", dev_path, "0", "create-md"])
-    if result.failed:
-      raise errors.BlockDeviceError("Can't initialize meta device: %s" %
-                                    result.output)
+    if not os.path.exists(self.dev_path):
+      _ThrowError("File device '%s' does not exist" % self.dev_path)

 
 

-  @classmethod
-  def _FindUnusedMinor(cls):
-    """Find an unused DRBD device.
+  def Shutdown(self):
+    """Shutdown the device.

 
 

-    This is specific to 8.x as the minors are allocated dynamically,
-    so non-existing numbers up to a max minor count are actually free.
+    This is a no-op for the file type, as we don't deactivate
+    the file on shutdown.

 
     """
 
     """

-    data = cls._GetProcData()
+    pass

 
 

-    unused_line = re.compile("^ *([0-9]+): cs:Unconfigured$")
-    used_line = re.compile("^ *([0-9]+): cs:")
-    highest = None
-    for line in data:
-      match = unused_line.match(line)
-      if match:
-        return int(match.group(1))
-      match = used_line.match(line)
-      if match:
-        minor = int(match.group(1))
-        highest = max(highest, minor)
-    if highest is None: # there are no minors in use at all
-      return 0
-    if highest >= cls._MAX_MINORS:
-      logger.Error("Error: no free drbd minors!")
-      raise errors.BlockDeviceError("Can't find a free DRBD minor")
-    return highest + 1
+  def Open(self, force=False):
+    """Make the device ready for I/O.

 
 

-  @classmethod
-  def _IsValidMeta(cls, meta_device):
-    """Check if the given meta device looks like a valid one.
+    This is a no-op for the file type.

 
     """
 
     """

-    minor = cls._FindUnusedMinor()
-    minor_path = cls._DevPath(minor)
-    result = utils.RunCmd(["drbdmeta", minor_path,
-                           "v08", meta_device, "0",
-                           "dstate"])
-    if result.failed:
-      logger.Error("Invalid meta device %s: %s" % (meta_device, result.output))
-      return False
-    return True
+    pass

 
 

-  @classmethod
-  def _GetShowParser(cls):
-    """Return a parser for `drbd show` output.
+  def Close(self):
+    """Notifies that the device will no longer be used for I/O.

 
 

-    This will either create or return an already-create parser for the
-    output of the command `drbd show`.
+    This is a no-op for the file type.

 
     """
 
     """

-    if cls._PARSE_SHOW is not None:
-      return cls._PARSE_SHOW
+    pass

 
 

-    # pyparsing setup
-    lbrace = pyp.Literal("{").suppress()
-    rbrace = pyp.Literal("}").suppress()
-    semi = pyp.Literal(";").suppress()
-    # this also converts the value to an int
-    number = pyp.Word(pyp.nums).setParseAction(lambda s, l, t:(l, [int(t[0])]))
+  def Remove(self):
+    """Remove the file backing the block device.

 
 

-    comment = pyp.Literal ("#") + pyp.Optional(pyp.restOfLine)
-    defa = pyp.Literal("_is_default").suppress()
-    dbl_quote = pyp.Literal('"').suppress()
+    @rtype: boolean
+    @return: True if the removal was successful

 
 

-    keyword = pyp.Word(pyp.alphanums + '-')
+    """
+    try:
+      os.remove(self.dev_path)
+    except OSError, err:
+      if err.errno != errno.ENOENT:
+        _ThrowError("Can't remove file '%s': %s", self.dev_path, err)

 
 

-    # value types
-    value = pyp.Word(pyp.alphanums + '_-/.:')
-    quoted = dbl_quote + pyp.CharsNotIn('"') + dbl_quote
-    addr_port = (pyp.Word(pyp.nums + '.') + pyp.Literal(':').suppress() +
-                 number)
-    # meta device, extended syntax
-    meta_value = ((value ^ quoted) + pyp.Literal('[').suppress() +
-                  number + pyp.Word(']').suppress())
+  def Rename(self, new_id):
+    """Renames the file.

 
 

-    # a statement
-    stmt = (~rbrace + keyword + ~lbrace +
-            (addr_port ^ value ^ quoted ^ meta_value) +
-            pyp.Optional(defa) + semi +
-            pyp.Optional(pyp.restOfLine).suppress())
+    """
+    # TODO: implement rename for file-based storage
+    _ThrowError("Rename is not supported for file-based storage")

 
 

-    # an entire section
-    section_name = pyp.Word(pyp.alphas + '_')
-    section = section_name + lbrace + pyp.ZeroOrMore(pyp.Group(stmt)) + rbrace
+  def Grow(self, amount, dryrun):
+    """Grow the file

 
 

-    bnf = pyp.ZeroOrMore(pyp.Group(section ^ stmt))
-    bnf.ignore(comment)
+    @param amount: the amount (in mebibytes) to grow with

 
 

-    cls._PARSE_SHOW = bnf
+    """
+    # Check that the file exists
+    self.Assemble()
+    current_size = self.GetActualSize()
+    new_size = current_size + amount * 1024 * 1024
+    assert new_size > current_size, "Cannot Grow with a negative amount"
+    # We can't really simulate the growth
+    if dryrun:
+      return
+    try:
+      f = open(self.dev_path, "a+")
+      f.truncate(new_size)
+      f.close()
+    except EnvironmentError, err:
+      _ThrowError("Error in file growth: %", str(err))

 
 

-    return bnf
+  def Attach(self):
+    """Attach to an existing file.

 
 

-  @classmethod
-  def _GetDevInfo(cls, minor):
-    """Get details about a given DRBD minor.
+    Check if this file already exists.

 
 

-    This return, if available, the local backing device (as a path)
-    and the local and remote (ip, port) information.
+    @rtype: boolean
+    @return: True if file exists

 
     """
 
     """

-    data = {}
-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "show"])
-    if result.failed:
-      logger.Error("Can't display the drbd config: %s" % result.fail_reason)
-      return data
-    out = result.stdout
-    if not out:
-      return data
+    self.attached = os.path.exists(self.dev_path)
+    return self.attached

 
 

-    bnf = cls._GetShowParser()
-    # run pyparse
+  def GetActualSize(self):
+    """Return the actual disk size.
+
+    @note: the device needs to be active when this is called

 
 

+    """
+    assert self.attached, "BlockDevice not attached in GetActualSize()"

     try:
     try:

-      results = bnf.parseString(out)
-    except pyp.ParseException, err:
-      raise errors.BlockDeviceError("Can't parse drbdsetup show output: %s" %
-                                    str(err))
+      st = os.stat(self.dev_path)
+      return st.st_size
+    except OSError, err:
+      _ThrowError("Can't stat %s: %s", self.dev_path, err)

 
 

-    # and massage the results into our desired format
-    for section in results:
-      sname = section[0]
-      if sname == "_this_host":
-        for lst in section[1:]:
-          if lst[0] == "disk":
-            data["local_dev"] = lst[1]
-          elif lst[0] == "meta-disk":
-            data["meta_dev"] = lst[1]
-            data["meta_index"] = lst[2]
-          elif lst[0] == "address":
-            data["local_addr"] = tuple(lst[1:])
-      elif sname == "_remote_host":
-        for lst in section[1:]:
-          if lst[0] == "address":
-            data["remote_addr"] = tuple(lst[1:])
-    return data
+  @classmethod
+  def Create(cls, unique_id, children, size, params):
+    """Create a new file.

 
 

-  def _MatchesLocal(self, info):
-    """Test if our local config matches with an existing device.
+    @param size: the size of file in MiB

 
 

-    The parameter should be as returned from `_GetDevInfo()`. This
-    method tests if our local backing device is the same as the one in
-    the info parameter, in effect testing if we look like the given
-    device.
+    @rtype: L{bdev.FileStorage}
+    @return: an instance of FileStorage

 
     """
 
     """

-    if self._children:
-      backend, meta = self._children
-    else:
-      backend = meta = None
+    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
+      raise ValueError("Invalid configuration data %s" % str(unique_id))
+    dev_path = unique_id[1]
+    try:
+      fd = os.open(dev_path, os.O_RDWR | os.O_CREAT | os.O_EXCL)
+      f = os.fdopen(fd, "w")
+      f.truncate(size * 1024 * 1024)
+      f.close()
+    except EnvironmentError, err:
+      if err.errno == errno.EEXIST:
+        _ThrowError("File already existing: %s", dev_path)
+      _ThrowError("Error in file creation: %", str(err))

 
 

-    if backend is not None:
-      retval = ("local_dev" in info and info["local_dev"] == backend.dev_path)
-    else:
-      retval = ("local_dev" not in info)
+    return FileStorage(unique_id, children, size, params)

 
 

-    if meta is not None:
-      retval = retval and ("meta_dev" in info and
-                           info["meta_dev"] == meta.dev_path)
-      retval = retval and ("meta_index" in info and
-                           info["meta_index"] == 0)
-    else:
-      retval = retval and ("meta_dev" not in info and
-                           "meta_index" not in info)
-    return retval

 
 

-  def _MatchesNet(self, info):
-    """Test if our network config matches with an existing device.
+class PersistentBlockDevice(BlockDev):
+  """A block device with persistent node
+
+  May be either directly attached, or exposed through DM (e.g. dm-multipath).
+  udev helpers are probably required to give persistent, human-friendly
+  names.
+
+  For the time being, pathnames are required to lie under /dev.
+
+  """
+  def __init__(self, unique_id, children, size, params):
+    """Attaches to a static block device.
+
+    The unique_id is a path under /dev.
+
+    """
+    super(PersistentBlockDevice, self).__init__(unique_id, children, size,
+                                                params)
+    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
+      raise ValueError("Invalid configuration data %s" % str(unique_id))
+    self.dev_path = unique_id[1]
+    if not os.path.realpath(self.dev_path).startswith("/dev/"):
+      raise ValueError("Full path '%s' lies outside /dev" %
+                              os.path.realpath(self.dev_path))
+    # TODO: this is just a safety guard checking that we only deal with devices
+    # we know how to handle. In the future this will be integrated with
+    # external storage backends and possible values will probably be collected
+    # from the cluster configuration.
+    if unique_id[0] != constants.BLOCKDEV_DRIVER_MANUAL:
+      raise ValueError("Got persistent block device of invalid type: %s" %
+                       unique_id[0])
+
+    self.major = self.minor = None
+    self.Attach()
+
+  @classmethod
+  def Create(cls, unique_id, children, size, params):
+    """Create a new device

 
 

-    The parameter should be as returned from `_GetDevInfo()`. This
-    method tests if our network configuration is the same as the one
-    in the info parameter, in effect testing if we look like the given
-    device.
+    This is a noop, we only return a PersistentBlockDevice instance

 
     """
 
     """

-    if (((self._lhost is None and not ("local_addr" in info)) and
-         (self._rhost is None and not ("remote_addr" in info)))):
-      return True
-
-    if self._lhost is None:
-      return False
+    return PersistentBlockDevice(unique_id, children, 0, params)

 
 

-    if not ("local_addr" in info and
-            "remote_addr" in info):
-      return False
+  def Remove(self):
+    """Remove a device

 
 

-    retval = (info["local_addr"] == (self._lhost, self._lport))
-    retval = (retval and
-              info["remote_addr"] == (self._rhost, self._rport))
-    return retval
+    This is a noop

 
 

-  @classmethod
-  def _AssembleLocal(cls, minor, backend, meta):
-    """Configure the local part of a DRBD device.
+    """
+    pass

 
 

-    This is the first thing that must be done on an unconfigured DRBD
-    device. And it must be done only once.
+  def Rename(self, new_id):
+    """Rename this device.

 
     """
 
     """

-    if not cls._IsValidMeta(meta):
-      return False
-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disk",
-                           backend, meta, "0", "-e", "detach",
-                           "--create-device"])
-    if result.failed:
-      logger.Error("Can't attach local disk: %s" % result.output)
-    return not result.failed
+    _ThrowError("Rename is not supported for PersistentBlockDev storage")
+
+  def Attach(self):
+    """Attach to an existing block device.

 
 

-  @classmethod
-  def _AssembleNet(cls, minor, net_info, protocol,
-                   dual_pri=False, hmac=None, secret=None):
-    """Configure the network part of the device.

 
     """
 
     """

-    lhost, lport, rhost, rport = net_info
-    args = ["drbdsetup", cls._DevPath(minor), "net",
-            "%s:%s" % (lhost, lport), "%s:%s" % (rhost, rport), protocol,
-            "-A", "discard-zero-changes",
-            "-B", "consensus",
-            ]
-    if dual_pri:
-      args.append("-m")
-    if hmac and secret:
-      args.extend(["-a", hmac, "-x", secret])
-    result = utils.RunCmd(args)
-    if result.failed:
-      logger.Error("Can't setup network for dbrd device: %s" %
-                   result.fail_reason)
+    self.attached = False
+    try:
+      st = os.stat(self.dev_path)
+    except OSError, err:
+      logging.error("Error stat()'ing %s: %s", self.dev_path, str(err))

       return False
 
       return False
 

-    timeout = time.time() + 10
-    ok = False
-    while time.time() < timeout:
-      info = cls._GetDevInfo(minor)
-      if not "local_addr" in info or not "remote_addr" in info:
-        time.sleep(1)
-        continue
-      if (info["local_addr"] != (lhost, lport) or
-          info["remote_addr"] != (rhost, rport)):
-        time.sleep(1)
-        continue
-      ok = True
-      break
-    if not ok:
-      logger.Error("Timeout while configuring network")
+    if not stat.S_ISBLK(st.st_mode):
+      logging.error("%s is not a block device", self.dev_path)

       return False
       return False

+
+    self.major = os.major(st.st_rdev)
+    self.minor = os.minor(st.st_rdev)
+    self.attached = True
+

     return True
 
     return True
 

-  def AddChildren(self, devices):
-    """Add a disk to the DRBD device.
+  def Assemble(self):
+    """Assemble the device.

 
     """
 
     """

-    if self.minor is None:
-      raise errors.BlockDeviceError("Can't attach to dbrd8 during AddChildren")
+    pass

 
 

-    if len(devices) != 2:
-      raise errors.BlockDeviceError("Need two devices for AddChildren")
-    if self._children:
-      raise errors.BlockDeviceError("DRBD8 already attached to a local disk")
-    backend, meta = devices
-    if backend.dev_path is None or meta.dev_path is None:
-      raise errors.BlockDeviceError("Children not ready during AddChildren")
-    backend.Open()
-    meta.Open()
-    if not self._CheckMetaSize(meta.dev_path):
-      raise errors.BlockDeviceError("Invalid meta device size")
-    self._InitMeta(self._FindUnusedMinor(), meta.dev_path)
-    if not self._IsValidMeta(meta.dev_path):
-      raise errors.BlockDeviceError("Cannot initalize meta device")
+  def Shutdown(self):
+    """Shutdown the device.

 
 

-    if not self._AssembleLocal(self.minor, backend.dev_path, meta.dev_path):
-      raise errors.BlockDeviceError("Can't attach to local storage")
-    self._children = devices
+    """
+    pass

 
 

-  def RemoveChildren(self, devices):
-    """Detach the drbd device from local storage.
+  def Open(self, force=False):
+    """Make the device ready for I/O.

 
     """
 
     """

-    if self.minor is None:
-      raise errors.BlockDeviceError("Can't attach to drbd8 during"
-                                    " RemoveChildren")
-    if len(self._children) != 2:
-      raise errors.BlockDeviceError("We don't have two children: %s" %
-                                    self._children)
-    if self._children.count(None) == 2: # we don't actually have children :)
-      logger.Error("Requested detach while detached")
-      return
-    if len(devices) != 2:
-      raise errors.BlockDeviceError("We need two children in RemoveChildren")
-    for child, dev in zip(self._children, devices):
-      if dev != child.dev_path:
-        raise errors.BlockDeviceError("Mismatch in local storage"
-                                      " (%s != %s) in RemoveChildren" %
-                                      (dev, child.dev_path))
-
-    if not self._ShutdownLocal(self.minor):
-      raise errors.BlockDeviceError("Can't detach from local storage")
-    self._children = []
+    pass

 
 

-  def SetSyncSpeed(self, kbytes):
-    """Set the speed of the DRBD syncer.
+  def Close(self):
+    """Notifies that the device will no longer be used for I/O.

 
     """
 
     """

-    children_result = super(DRBD8, self).SetSyncSpeed(kbytes)
-    if self.minor is None:
-      logger.Info("Instance not attached to a device")
-      return False
-    result = utils.RunCmd(["drbdsetup", self.dev_path, "syncer", "-r", "%d" %
-                           kbytes])
-    if result.failed:
-      logger.Error("Can't change syncer rate: %s " % result.fail_reason)
-    return not result.failed and children_result
+    pass

 
 

-  def GetSyncStatus(self):
-    """Returns the sync status of the device.
+  def Grow(self, amount, dryrun):
+    """Grow the logical volume.

 
 

-    Returns:
-     (sync_percent, estimated_time, is_degraded)
+    """
+    _ThrowError("Grow is not supported for PersistentBlockDev storage")

 
 

-    If sync_percent is None, it means all is ok
-    If estimated_time is None, it means we can't esimate
-    the time needed, otherwise it's the time left in seconds

 
 

-    """
-    if self.minor is None and not self.Attach():
-      raise errors.BlockDeviceError("Can't attach to device in GetSyncStatus")
-    proc_info = self._MassageProcData(self._GetProcData())
-    if self.minor not in proc_info:
-      raise errors.BlockDeviceError("Can't find myself in /proc (minor %d)" %
-                                    self.minor)
-    line = proc_info[self.minor]
-    match = re.match("^.*sync'ed: *([0-9.]+)%.*"
-                     " finish: ([0-9]+):([0-9]+):([0-9]+) .*$", line)
-    if match:
-      sync_percent = float(match.group(1))
-      hours = int(match.group(2))
-      minutes = int(match.group(3))
-      seconds = int(match.group(4))
-      est_time = hours * 3600 + minutes * 60 + seconds
-    else:
-      sync_percent = None
-      est_time = None
-    match = re.match("^ *\d+: cs:(\w+).*ds:(\w+)/(\w+).*$", line)
-    if not match:
-      raise errors.BlockDeviceError("Can't find my data in /proc (minor %d)" %
-                                    self.minor)
-    client_state = match.group(1)
-    local_disk_state = match.group(2)
-    is_degraded = (client_state != "Connected" or
-                   local_disk_state != "UpToDate")
-    return sync_percent, est_time, is_degraded
+class RADOSBlockDevice(BlockDev):
+  """A RADOS Block Device (rbd).

 
 

-  def GetStatus(self):
-    """Compute the status of the DRBD device
+  This class implements the RADOS Block Device for the backend. You need
+  the rbd kernel driver, the RADOS Tools and a working RADOS cluster for
+  this to be functional.

 
 

-    Note that DRBD devices don't have the STATUS_EXISTING state.
+  """
+  def __init__(self, unique_id, children, size, params):
+    """Attaches to an rbd device.

 
     """
 
     """

-    if self.minor is None and not self.Attach():
-      return self.STATUS_UNKNOWN
-
-    data = self._GetProcData()
-    match = re.compile("^ *%d: cs:[^ ]+ st:(Primary|Secondary)/.*$" %
-                       self.minor)
-    for line in data:
-      mresult = match.match(line)
-      if mresult:
-        break
-    else:
-      logger.Error("Can't find myself!")
-      return self.STATUS_UNKNOWN
+    super(RADOSBlockDevice, self).__init__(unique_id, children, size, params)
+    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
+      raise ValueError("Invalid configuration data %s" % str(unique_id))

 
 

-    state = mresult.group(2)
-    if state == "Primary":
-      result = self.STATUS_ONLINE
-    else:
-      result = self.STATUS_STANDBY
+    self.driver, self.rbd_name = unique_id

 
 

-    return result
+    self.major = self.minor = None
+    self.Attach()

 
 

-  def Open(self, force=False):
-    """Make the local state primary.
+  @classmethod
+  def Create(cls, unique_id, children, size, params):
+    """Create a new rbd device.

 
 

-    If the 'force' parameter is given, the '--do-what-I-say' parameter
-    is given. Since this is a pottentialy dangerous operation, the
-    force flag should be only given after creation, when it actually
-    has to be given.
+    Provision a new rbd volume inside a RADOS pool.

 
     """
 
     """

-    if self.minor is None and not self.Attach():
-      logger.Error("DRBD cannot attach to a device during open")
-      return False
-    cmd = ["drbdsetup", self.dev_path, "primary"]
-    if force:
-      cmd.append("-o")
+    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
+      raise errors.ProgrammerError("Invalid configuration data %s" %
+                                   str(unique_id))
+    rbd_pool = params[constants.LDP_POOL]
+    rbd_name = unique_id[1]
+
+    # Provision a new rbd volume (Image) inside the RADOS cluster.
+    cmd = [constants.RBD_CMD, "create", "-p", rbd_pool,
+           rbd_name, "--size", "%s" % size]

     result = utils.RunCmd(cmd)
     if result.failed:
     result = utils.RunCmd(cmd)
     if result.failed:

-      logger.Error("Can't make drbd device primary: %s" % result.output)
-      return False
-    return True
+      _ThrowError("rbd creation failed (%s): %s",
+                  result.fail_reason, result.output)

 
 

-  def Close(self):
-    """Make the local state secondary.
+    return RADOSBlockDevice(unique_id, children, size, params)

 
 

-    This will, of course, fail if the device is in use.
+  def Remove(self):
+    """Remove the rbd device.

 
     """
 
     """

-    if self.minor is None and not self.Attach():
-      logger.Info("Instance not attached to a device")
-      raise errors.BlockDeviceError("Can't find device")
-    result = utils.RunCmd(["drbdsetup", self.dev_path, "secondary"])
+    rbd_pool = self.params[constants.LDP_POOL]
+    rbd_name = self.unique_id[1]
+
+    if not self.minor and not self.Attach():
+      # The rbd device doesn't exist.
+      return
+
+    # First shutdown the device (remove mappings).
+    self.Shutdown()
+
+    # Remove the actual Volume (Image) from the RADOS cluster.
+    cmd = [constants.RBD_CMD, "rm", "-p", rbd_pool, rbd_name]
+    result = utils.RunCmd(cmd)

     if result.failed:
     if result.failed:

-      logger.Error("Can't switch drbd device to secondary: %s" % result.output)
-      raise errors.BlockDeviceError("Can't switch drbd device to secondary")
+      _ThrowError("Can't remove Volume from cluster with rbd rm: %s - %s",
+                  result.fail_reason, result.output)
+
+  def Rename(self, new_id):
+    """Rename this device.
+
+    """
+    pass

 
   def Attach(self):
 
   def Attach(self):

-    """Find a DRBD device which matches our config and attach to it.
+    """Attach to an existing rbd device.

 
 

-    In case of partially attached (local device matches but no network
-    setup), we perform the network attach. If successful, we re-test
-    the attach if can return success.
+    This method maps the rbd volume that matches our name with
+    an rbd device and then attaches to this device.

 
     """
 
     """

-    for minor in self._GetUsedDevs():
-      info = self._GetDevInfo(minor)
-      match_l = self._MatchesLocal(info)
-      match_r = self._MatchesNet(info)
-      if match_l and match_r:
-        break
-      if match_l and not match_r and "local_addr" not in info:
-        res_r = self._AssembleNet(minor,
-                                  (self._lhost, self._lport,
-                                   self._rhost, self._rport),
-                                  "C")
-        if res_r and self._MatchesNet(self._GetDevInfo(minor)):
-          break
-      # the weakest case: we find something that is only net attached
-      # even though we were passed some children at init time
-      if match_r and "local_dev" not in info:
-        break
-    else:
-      minor = None
-
-    self._SetFromMinor(minor)
-    return minor is not None
+    self.attached = False

 
 

-  def Assemble(self):
-    """Assemble the drbd.
+    # Map the rbd volume to a block device under /dev
+    self.dev_path = self._MapVolumeToBlockdev(self.unique_id)

 
 

-    Method:
-      - if we have a local backing device, we bind to it by:
-        - checking the list of used drbd devices
-        - check if the local minor use of any of them is our own device
-        - if yes, abort?
-        - if not, bind
-      - if we have a local/remote net info:
-        - redo the local backing device step for the remote device
-        - check if any drbd device is using the local port,
-          if yes abort
-        - check if any remote drbd device is using the remote
-          port, if yes abort (for now)
-        - bind our net port
-        - bind the remote net port
+    try:
+      st = os.stat(self.dev_path)
+    except OSError, err:
+      logging.error("Error stat()'ing %s: %s", self.dev_path, str(err))
+      return False

 
 

-    """
-    self.Attach()
-    if self.minor is not None:
-      logger.Info("Already assembled")
-      return True
+    if not stat.S_ISBLK(st.st_mode):
+      logging.error("%s is not a block device", self.dev_path)
+      return False

 
 

-    result = super(DRBD8, self).Assemble()
-    if not result:
-      return result
+    self.major = os.major(st.st_rdev)
+    self.minor = os.minor(st.st_rdev)
+    self.attached = True

 
 

-    minor = self._FindUnusedMinor()
-    need_localdev_teardown = False
-    if self._children and self._children[0] and self._children[1]:
-      result = self._AssembleLocal(minor, self._children[0].dev_path,
-                                   self._children[1].dev_path)
-      if not result:
-        return False
-      need_localdev_teardown = True
-    if self._lhost and self._lport and self._rhost and self._rport:
-      result = self._AssembleNet(minor,
-                                 (self._lhost, self._lport,
-                                  self._rhost, self._rport),
-                                 "C")
-      if not result:
-        if need_localdev_teardown:
-          # we will ignore failures from this
-          logger.Error("net setup failed, tearing down local device")
-          self._ShutdownAll(minor)
-        return False
-    self._SetFromMinor(minor)

     return True
 
     return True
 

-  @classmethod
-  def _ShutdownLocal(cls, minor):
-    """Detach from the local device.
+  def _MapVolumeToBlockdev(self, unique_id):
+    """Maps existing rbd volumes to block devices.

 
 

-    I/Os will continue to be served from the remote device. If we
-    don't have a remote device, this operation will fail.
+    This method should be idempotent if the mapping already exists.
+
+    @rtype: string
+    @return: the block device path that corresponds to the volume

 
     """
 
     """

-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "detach"])
+    pool = self.params[constants.LDP_POOL]
+    name = unique_id[1]
+
+    # Check if the mapping already exists.
+    showmap_cmd = [constants.RBD_CMD, "showmapped", "-p", pool]
+    result = utils.RunCmd(showmap_cmd)

     if result.failed:
     if result.failed:

-      logger.Error("Can't detach local device: %s" % result.output)
-    return not result.failed
+      _ThrowError("rbd showmapped failed (%s): %s",
+                  result.fail_reason, result.output)

 
 

-  @classmethod
-  def _ShutdownNet(cls, minor):
-    """Disconnect from the remote peer.
+    rbd_dev = self._ParseRbdShowmappedOutput(result.output, name)

 
 

-    This fails if we don't have a local device.
+    if rbd_dev:
+      # The mapping exists. Return it.
+      return rbd_dev
+
+    # The mapping doesn't exist. Create it.
+    map_cmd = [constants.RBD_CMD, "map", "-p", pool, name]
+    result = utils.RunCmd(map_cmd)
+    if result.failed:
+      _ThrowError("rbd map failed (%s): %s",
+                  result.fail_reason, result.output)
+
+    # Find the corresponding rbd device.
+    showmap_cmd = [constants.RBD_CMD, "showmapped", "-p", pool]
+    result = utils.RunCmd(showmap_cmd)
+    if result.failed:
+      _ThrowError("rbd map succeeded, but showmapped failed (%s): %s",
+                  result.fail_reason, result.output)
+
+    rbd_dev = self._ParseRbdShowmappedOutput(result.output, name)
+
+    if not rbd_dev:
+      _ThrowError("rbd map succeeded, but could not find the rbd block"
+                  " device in output of showmapped, for volume: %s", name)
+
+    # The device was successfully mapped. Return it.
+    return rbd_dev
+
+  @staticmethod
+  def _ParseRbdShowmappedOutput(output, volume_name):
+    """Parse the output of `rbd showmapped'.
+
+    This method parses the output of `rbd showmapped' and returns
+    the rbd block device path (e.g. /dev/rbd0) that matches the
+    given rbd volume.
+
+    @type output: string
+    @param output: the whole output of `rbd showmapped'
+    @type volume_name: string
+    @param volume_name: the name of the volume whose device we search for
+    @rtype: string or None
+    @return: block device path if the volume is mapped, else None

 
     """
 
     """

-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disconnect"])
-    logger.Error("Can't shutdown network: %s" % result.output)
-    return not result.failed
+    allfields = 5
+    volumefield = 2
+    devicefield = 4

 
 

-  @classmethod
-  def _ShutdownAll(cls, minor):
-    """Deactivate the device.
+    field_sep = "\t"

 
 

-    This will, of course, fail if the device is in use.
+    lines = output.splitlines()
+    splitted_lines = map(lambda l: l.split(field_sep), lines)
+
+    # Check empty output.
+    if not splitted_lines:
+      _ThrowError("rbd showmapped returned empty output")
+
+    # Check showmapped header line, to determine number of fields.
+    field_cnt = len(splitted_lines[0])
+    if field_cnt != allfields:
+      _ThrowError("Cannot parse rbd showmapped output because its format"
+                  " seems to have changed; expected %s fields, found %s",
+                  allfields, field_cnt)
+
+    matched_lines = \
+      filter(lambda l: len(l) == allfields and l[volumefield] == volume_name,
+             splitted_lines)
+
+    if len(matched_lines) > 1:
+      _ThrowError("The rbd volume %s is mapped more than once."
+                  " This shouldn't happen, try to unmap the extra"
+                  " devices manually.", volume_name)
+
+    if matched_lines:
+      # rbd block device found. Return it.
+      rbd_dev = matched_lines[0][devicefield]
+      return rbd_dev
+
+    # The given volume is not mapped.
+    return None
+
+  def Assemble(self):
+    """Assemble the device.

 
     """
 
     """

-    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "down"])
-    if result.failed:
-      logger.Error("Can't shutdown drbd device: %s" % result.output)
-    return not result.failed
+    pass

 
   def Shutdown(self):
 
   def Shutdown(self):

-    """Shutdown the DRBD device.
+    """Shutdown the device.

 
     """
 
     """

-    if self.minor is None and not self.Attach():
-      logger.Info("DRBD device not attached to a device during Shutdown")
-      return True
-    if not self._ShutdownAll(self.minor):
-      return False
+    if not self.minor and not self.Attach():
+      # The rbd device doesn't exist.
+      return
+
+    # Unmap the block device from the Volume.
+    self._UnmapVolumeFromBlockdev(self.unique_id)
+

     self.minor = None
     self.dev_path = None
     self.minor = None
     self.dev_path = None

-    return True

 
 

-  def Rename(self, new_uid):
-    """Re-connect this device to another peer.
+  def _UnmapVolumeFromBlockdev(self, unique_id):
+    """Unmaps the rbd device from the Volume it is mapped.
+
+    Unmaps the rbd device from the Volume it was previously mapped to.
+    This method should be idempotent if the Volume isn't mapped.

 
     """
 
     """

-    if self.minor is None:
-      raise errors.BlockDeviceError("Device not attached during rename")
-    if self._rhost is not None:
-      # this means we did have a host when we attached, so we are connected
-      if not self._ShutdownNet(self.minor):
-        raise errors.BlockDeviceError("Can't disconnect from remote peer")
-      old_id = self.unique_id
-    else:
-      old_id = None
-    self.unique_id = new_uid
-    if not self._AssembleNet(self.minor, self.unique_id, "C"):
-      logger.Error("Can't attach to new peer!")
-      if old_id is not None:
-        self._AssembleNet(self.minor, old_id, "C")
-      self.unique_id = old_id
-      raise errors.BlockDeviceError("Can't attach to new peer")
+    pool = self.params[constants.LDP_POOL]
+    name = unique_id[1]

 
 

-  def Remove(self):
-    """Stub remove for DRBD devices.
+    # Check if the mapping already exists.
+    showmap_cmd = [constants.RBD_CMD, "showmapped", "-p", pool]
+    result = utils.RunCmd(showmap_cmd)
+    if result.failed:
+      _ThrowError("rbd showmapped failed [during unmap](%s): %s",
+                  result.fail_reason, result.output)
+
+    rbd_dev = self._ParseRbdShowmappedOutput(result.output, name)
+
+    if rbd_dev:
+      # The mapping exists. Unmap the rbd device.
+      unmap_cmd = [constants.RBD_CMD, "unmap", "%s" % rbd_dev]
+      result = utils.RunCmd(unmap_cmd)
+      if result.failed:
+        _ThrowError("rbd unmap failed (%s): %s",
+                    result.fail_reason, result.output)
+
+  def Open(self, force=False):
+    """Make the device ready for I/O.

 
     """
 
     """

-    return self.Shutdown()
+    pass

 
 

-  @classmethod
-  def Create(cls, unique_id, children, size):
-    """Create a new DRBD8 device.
+  def Close(self):
+    """Notifies that the device will no longer be used for I/O.

 
 

-    Since DRBD devices are not created per se, just assembled, this
-    function only initializes the metadata.
+    """
+    pass
+
+  def Grow(self, amount, dryrun):
+    """Grow the Volume.
+
+    @type amount: integer
+    @param amount: the amount (in mebibytes) to grow with
+    @type dryrun: boolean
+    @param dryrun: whether to execute the operation in simulation mode
+        only, without actually increasing the size

 
     """
 
     """

-    if len(children) != 2:
-      raise errors.ProgrammerError("Invalid setup for the drbd device")
-    meta = children[1]
-    meta.Assemble()
-    if not meta.Attach():
-      raise errors.BlockDeviceError("Can't attach to meta device")
-    if not cls._CheckMetaSize(meta.dev_path):
-      raise errors.BlockDeviceError("Invalid meta device size")
-    cls._InitMeta(cls._FindUnusedMinor(), meta.dev_path)
-    if not cls._IsValidMeta(meta.dev_path):
-      raise errors.BlockDeviceError("Cannot initalize meta device")
-    return cls(unique_id, children)
+    if not self.Attach():
+      _ThrowError("Can't attach to rbd device during Grow()")
+
+    if dryrun:
+      # the rbd tool does not support dry runs of resize operations.
+      # Since rbd volumes are thinly provisioned, we assume
+      # there is always enough free space for the operation.
+      return
+
+    rbd_pool = self.params[constants.LDP_POOL]
+    rbd_name = self.unique_id[1]
+    new_size = self.size + amount
+
+    # Resize the rbd volume (Image) inside the RADOS cluster.
+    cmd = [constants.RBD_CMD, "resize", "-p", rbd_pool,
+           rbd_name, "--size", "%s" % new_size]
+    result = utils.RunCmd(cmd)
+    if result.failed:
+      _ThrowError("rbd resize failed (%s): %s",
+                  result.fail_reason, result.output)

 
 
 DEV_MAP = {
   constants.LD_LV: LogicalVolume,
 
 
 DEV_MAP = {
   constants.LD_LV: LogicalVolume,

-  constants.LD_MD_R1: MDRaid1,
-  constants.LD_DRBD7: DRBDev,

   constants.LD_DRBD8: DRBD8,
   constants.LD_DRBD8: DRBD8,

+  constants.LD_BLOCKDEV: PersistentBlockDevice,
+  constants.LD_RBD: RADOSBlockDevice,

   }
 
   }
 

+if constants.ENABLE_FILE_STORAGE or constants.ENABLE_SHARED_FILE_STORAGE:
+  DEV_MAP[constants.LD_FILE] = FileStorage
+
+
+def _VerifyDiskType(dev_type):
+  if dev_type not in DEV_MAP:
+    raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type)
+

 
 

-def FindDevice(dev_type, unique_id, children):
+def FindDevice(disk, children):

   """Search for an existing, assembled device.
 
   This will succeed only if the device exists and is assembled, but it
   does not do any actions in order to activate the device.
 
   """Search for an existing, assembled device.
 
   This will succeed only if the device exists and is assembled, but it
   does not do any actions in order to activate the device.
 

+  @type disk: L{objects.Disk}
+  @param disk: the disk object to find
+  @type children: list of L{bdev.BlockDev}
+  @param children: the list of block devices that are children of the device
+                  represented by the disk parameter
+

   """
   """

-  if dev_type not in DEV_MAP:
-    raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type)
-  device = DEV_MAP[dev_type](unique_id, children)
-  if not device.Attach():
+  _VerifyDiskType(disk.dev_type)
+  dev_params = objects.FillDict(constants.DISK_LD_DEFAULTS[disk.dev_type],
+                                disk.params)
+  device = DEV_MAP[disk.dev_type](disk.physical_id, children, disk.size,
+                                  dev_params)
+  if not device.attached:

     return None
     return None

-  return  device
+  return device

 
 
 
 

-def AttachOrAssemble(dev_type, unique_id, children):
+def Assemble(disk, children):

   """Try to attach or assemble an existing device.
 
   """Try to attach or assemble an existing device.
 

-  This will attach to an existing assembled device or will assemble
-  the device, as needed, to bring it fully up.
+  This will attach to assemble the device, as needed, to bring it
+  fully up. It must be safe to run on already-assembled devices.
+
+  @type disk: L{objects.Disk}
+  @param disk: the disk object to assemble
+  @type children: list of L{bdev.BlockDev}
+  @param children: the list of block devices that are children of the device
+                  represented by the disk parameter

 
   """
 
   """

-  if dev_type not in DEV_MAP:
-    raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type)
-  device = DEV_MAP[dev_type](unique_id, children)
-  if not device.Attach():
-    device.Assemble()
-  if not device.Attach():
-    raise errors.BlockDeviceError("Can't find a valid block device for"
-                                  " %s/%s/%s" %
-                                  (dev_type, unique_id, children))
+  _VerifyDiskType(disk.dev_type)
+  dev_params = objects.FillDict(constants.DISK_LD_DEFAULTS[disk.dev_type],
+                                disk.params)
+  device = DEV_MAP[disk.dev_type](disk.physical_id, children, disk.size,
+                                  dev_params)
+  device.Assemble()

   return device
 
 
   return device
 
 

-def Create(dev_type, unique_id, children, size):
+def Create(disk, children):

   """Create a device.
 
   """Create a device.
 

+  @type disk: L{objects.Disk}
+  @param disk: the disk object to create
+  @type children: list of L{bdev.BlockDev}
+  @param children: the list of block devices that are children of the device
+                  represented by the disk parameter
+

   """
   """

-  if dev_type not in DEV_MAP:
-    raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type)
-  device = DEV_MAP[dev_type].Create(unique_id, children, size)
+  _VerifyDiskType(disk.dev_type)
+  dev_params = objects.FillDict(constants.DISK_LD_DEFAULTS[disk.dev_type],
+                                disk.params)
+  device = DEV_MAP[disk.dev_type].Create(disk.physical_id, children, disk.size,
+                                         dev_params)

   return device
   return device