hv_chroot: remove hard-coded path constructs

[ganeti-local] / lib / bdev.py

diff --git a/lib/bdev.py b/lib/bdev.py
index d2d62c8..bdfbec7 100644 (file)
--- a/lib/bdev.py
+++ b/lib/bdev.py
@@ -34,6 +34,10 @@ from ganeti import constants
 from ganeti import objects
 
 
 from ganeti import objects
 
 

+# Size of reads in _CanReadDevice
+_DEVICE_READ_SIZE = 128 * 1024
+
+

 def _IgnoreError(fn, *args, **kwargs):
   """Executes the given function, ignoring BlockDeviceErrors.
 
 def _IgnoreError(fn, *args, **kwargs):
   """Executes the given function, ignoring BlockDeviceErrors.
 

@@ -48,7 +52,7 @@ def _IgnoreError(fn, *args, **kwargs):
     fn(*args, **kwargs)
     return True
   except errors.BlockDeviceError, err:
     fn(*args, **kwargs)
     return True
   except errors.BlockDeviceError, err:

-    logging.warning("Caught BlockDeviceError but ignoring: %s" % str(err))
+    logging.warning("Caught BlockDeviceError but ignoring: %s", str(err))

     return False
 
 
     return False
 
 

@@ -66,6 +70,20 @@ def _ThrowError(msg, *args):
   raise errors.BlockDeviceError(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):
   """Block device abstract class.
 
 class BlockDev(object):
   """Block device abstract class.
 

@@ -331,6 +349,10 @@ class LogicalVolume(BlockDev):
   """Logical Volume block device.
 
   """
   """Logical Volume block device.
 
   """

+  _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):
     """Attaches to a LV device.
 
   def __init__(self, unique_id, children, size):
     """Attaches to a LV device.
 

@@ -341,7 +363,9 @@ class LogicalVolume(BlockDev):
     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()
     self._degraded = True
     self.major = self.minor = self.pe_size = self.stripe_count = None
     self.Attach()

@@ -355,7 +379,9 @@ class LogicalVolume(BlockDev):
       raise errors.ProgrammerError("Invalid configuration data %s" %
                                    str(unique_id))
     vg_name, lv_name = unique_id
       raise errors.ProgrammerError("Invalid configuration data %s" %
                                    str(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:
       _ThrowError("Can't compute PV info for vg %s", vg_name)
     pvs_info.sort()
     if not pvs_info:
       _ThrowError("Can't compute PV info for vg %s", vg_name)
     pvs_info.sort()

@@ -389,10 +415,11 @@ class LogicalVolume(BlockDev):
     return LogicalVolume(unique_id, children, size)
 
   @staticmethod
     return LogicalVolume(unique_id, children, size)
 
   @staticmethod

-  def GetPVInfo(vg_name):
+  def GetPVInfo(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.
 

-    @param 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

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

@@ -413,13 +440,30 @@ class LogicalVolume(BlockDev):
       if len(fields) != 4:
         logging.error("Can't parse pvs output: line '%s'", line)
         return None
       if len(fields) != 4:
         logging.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':
+      # (possibly) skip over pvs which are not allocatable
+      if filter_allocatable and fields[3][0] != 'a':
+        continue
+      # (possibly) skip over pvs which are not in the right volume group(s)
+      if vg_names and fields[1] not in vg_names:

         continue
         continue

-      data.append((float(fields[2]), fields[0]))
+      data.append((float(fields[2]), fields[0], fields[1]))

 
     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
+        utils.any(cls._INVALID_SUBSTRINGS, lambda x: x in name)):
+      _ThrowError("Invalid LVM name '%s'", name)
+

   def Remove(self):
     """Remove this logical volume.
 
   def Remove(self):
     """Remove this logical volume.
 

@@ -447,7 +491,7 @@ class LogicalVolume(BlockDev):
     if result.failed:
       _ThrowError("Failed to rename the logical volume: %s", result.output)
     self._lv_name = new_name
     if result.failed:
       _ThrowError("Failed to rename the logical volume: %s", result.output)
     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.
 
   def Attach(self):
     """Attach to an existing LV.

@@ -490,7 +534,7 @@ class LogicalVolume(BlockDev):
     try:
       major = int(major)
       minor = int(minor)
     try:
       major = int(major)
       minor = int(minor)

-    except ValueError, err:
+    except (TypeError, ValueError), err:

       logging.error("lvs major/minor cannot be parsed: %s", str(err))
 
     try:
       logging.error("lvs major/minor cannot be parsed: %s", str(err))
 
     try:

@@ -596,12 +640,12 @@ class LogicalVolume(BlockDev):
     snap = LogicalVolume((self._vg_name, snap_name), None, size)
     _IgnoreError(snap.Remove)
 
     snap = LogicalVolume((self._vg_name, snap_name), None, size)
     _IgnoreError(snap.Remove)
 

-    pvs_info = self.GetPVInfo(self._vg_name)
+    pvs_info = self.GetPVInfo([self._vg_name])

     if not pvs_info:
       _ThrowError("Can't compute PV info for vg %s", self._vg_name)
     pvs_info.sort()
     pvs_info.reverse()
     if not pvs_info:
       _ThrowError("Can't compute PV info for vg %s", self._vg_name)
     pvs_info.sort()
     pvs_info.reverse()

-    free_size, pv_name = pvs_info[0]
+    free_size, _, _ = pvs_info[0]

     if free_size < size:
       _ThrowError("Not enough free space: required %s,"
                   " available %s", size, free_size)
     if free_size < size:
       _ThrowError("Not enough free space: required %s,"
                   " available %s", size, free_size)

@@ -761,7 +805,7 @@ class DRBD8Status(object):
       self.est_time = None
 
 
       self.est_time = None
 
 

-class BaseDRBD(BlockDev):
+class BaseDRBD(BlockDev): # pylint: disable-msg=W0223

   """Base DRBD class.
 
   This class contains a few bits of common functionality between the
   """Base DRBD class.
 
   This class contains a few bits of common functionality between the

@@ -770,6 +814,8 @@ class BaseDRBD(BlockDev):
   """
   _VERSION_RE = re.compile(r"^version: (\d+)\.(\d+)\.(\d+)"
                            r" \(api:(\d+)/proto:(\d+)(?:-(\d+))?\)")
   """
   _VERSION_RE = re.compile(r"^version: (\d+)\.(\d+)\.(\d+)"
                            r" \(api:(\d+)/proto:(\d+)(?:-(\d+))?\)")

+  _VALID_LINE_RE = re.compile("^ *([0-9]+): cs:([^ ]+).*$")
+  _UNUSED_LINE_RE = re.compile("^ *([0-9]+): cs:Unconfigured$")

 
   _DRBD_MAJOR = 147
   _ST_UNCONFIGURED = "Unconfigured"
 
   _DRBD_MAJOR = 147
   _ST_UNCONFIGURED = "Unconfigured"

@@ -795,21 +841,20 @@ class BaseDRBD(BlockDev):
       _ThrowError("Can't read any data from %s", filename)
     return data
 
       _ThrowError("Can't read any data from %s", filename)
     return data
 

-  @staticmethod
-  def _MassageProcData(data):
+  @classmethod
+  def _MassageProcData(cls, data):

     """Transform the output of _GetProdData into a nicer form.
 
     @return: a dictionary of minor: joined lines from /proc/drbd
         for that minor
 
     """
     """Transform the output of _GetProdData into a nicer form.
 
     @return: a dictionary of minor: joined lines from /proc/drbd
         for that minor
 
     """

-    lmatch = re.compile("^ *([0-9]+):.*$")

     results = {}
     old_minor = old_line = None
     for line in data:
       if not line: # completely empty lines, as can be returned by drbd8.0+
         continue
     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 = lmatch.match(line)
+      lresult = cls._VALID_LINE_RE.match(line)

       if lresult is not None:
         if old_minor is not None:
           results[old_minor] = old_line
       if lresult is not None:
         if old_minor is not None:
           results[old_minor] = old_line

@@ -870,9 +915,8 @@ class BaseDRBD(BlockDev):
     data = cls._GetProcData()
 
     used_devs = {}
     data = cls._GetProcData()
 
     used_devs = {}

-    valid_line = re.compile("^ *([0-9]+): cs:([^ ]+).*$")

     for line in data:
     for line in data:

-      match = valid_line.match(line)
+      match = cls._VALID_LINE_RE.match(line)

       if not match:
         continue
       minor = int(match.group(1))
       if not match:
         continue
       minor = int(match.group(1))

@@ -911,7 +955,7 @@ class BaseDRBD(BlockDev):
                   result.fail_reason, result.output)
     try:
       sectors = int(result.stdout)
                   result.fail_reason, result.output)
     try:
       sectors = int(result.stdout)

-    except ValueError:
+    except (TypeError, ValueError):

       _ThrowError("Invalid output from blockdev: '%s'", result.stdout)
     bytes = sectors * 512
     if bytes < 128 * 1024 * 1024: # less than 128MiB
       _ThrowError("Invalid output from blockdev: '%s'", result.stdout)
     bytes = sectors * 512
     if bytes < 128 * 1024 * 1024: # less than 128MiB

@@ -956,6 +1000,17 @@ class DRBD8(BaseDRBD):
   def __init__(self, unique_id, children, size):
     if children and children.count(None) > 0:
       children = []
   def __init__(self, unique_id, children, size):
     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)
     self.major = self._DRBD_MAJOR
     version = self._GetVersion()
     super(DRBD8, self).__init__(unique_id, children, size)
     self.major = self._DRBD_MAJOR
     version = self._GetVersion()

@@ -964,13 +1019,6 @@ class DRBD8(BaseDRBD):
                   " usage: kernel is %s.%s, ganeti wants 8.x",
                   version['k_major'], version['k_minor'])
 
                   " usage: kernel is %s.%s, ganeti wants 8.x",
                   version['k_major'], version['k_minor'])
 

-    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 (self._lhost is not None and self._lhost == self._rhost and
         self._lport == self._rport):
       raise ValueError("Invalid configuration data, same local/remote %s" %
     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" %

@@ -999,14 +1047,12 @@ class DRBD8(BaseDRBD):
     """
     data = cls._GetProcData()
 
     """
     data = cls._GetProcData()
 

-    unused_line = re.compile("^ *([0-9]+): cs:Unconfigured$")
-    used_line = re.compile("^ *([0-9]+): cs:")

     highest = None
     for line in data:
     highest = None
     for line in data:

-      match = unused_line.match(line)
+      match = cls._UNUSED_LINE_RE.match(line)

       if match:
         return int(match.group(1))
       if match:
         return int(match.group(1))

-      match = used_line.match(line)
+      match = cls._VALID_LINE_RE.match(line)

       if match:
         minor = int(match.group(1))
         highest = max(highest, minor)
       if match:
         minor = int(match.group(1))
         highest = max(highest, minor)

@@ -1189,6 +1235,24 @@ class DRBD8(BaseDRBD):
             "--create-device"]
     if size:
       args.extend(["-d", "%sm" % size])
             "--create-device"]
     if size:
       args.extend(["-d", "%sm" % size])

+    if not constants.DRBD_BARRIERS: # disable barriers, if configured so
+      version = cls._GetVersion()
+      # various DRBD versions support different disk barrier options;
+      # what we aim here is to revert back to the 'drain' method of
+      # disk flushes and to disable metadata barriers, in effect going
+      # back to pre-8.0.7 behaviour
+      vmaj = version['k_major']
+      vmin = version['k_minor']
+      vrel = version['k_point']
+      assert vmaj == 8
+      if vmin == 0: # 8.0.x
+        if vrel >= 12:
+          args.extend(['-i', '-m'])
+      elif vmin == 2: # 8.2.x
+        if vrel >= 7:
+          args.extend(['-i', '-m'])
+      elif vmaj >= 3: # 8.3.x or newer
+        args.extend(['-i', '-a', 'm'])

     result = utils.RunCmd(args)
     if result.failed:
       _ThrowError("drbd%d: can't attach local disk: %s", minor, result.output)
     result = utils.RunCmd(args)
     if result.failed:
       _ThrowError("drbd%d: can't attach local disk: %s", minor, result.output)

@@ -1547,6 +1611,8 @@ class DRBD8(BaseDRBD):
     the attach if can return success.
 
     """
     the attach if can return success.
 
     """

+    # TODO: Rewrite to not use a for loop just because there is 'break'
+    # pylint: disable-msg=W0631

     net_data = (self._lhost, self._lport, self._rhost, self._rport)
     for minor in (self._aminor,):
       info = self._GetDevInfo(self._GetShowData(minor))
     net_data = (self._lhost, self._lport, self._rhost, self._rport)
     for minor in (self._aminor,):
       info = self._GetDevInfo(self._GetShowData(minor))

@@ -1794,6 +1860,22 @@ class FileStorage(BlockDev):
       if err.errno != errno.ENOENT:
         _ThrowError("Can't remove file '%s': %s", self.dev_path, err)
 
       if err.errno != errno.ENOENT:
         _ThrowError("Can't remove file '%s': %s", self.dev_path, err)
 

+  def Rename(self, new_id):
+    """Renames the file.
+
+    """
+    # TODO: implement rename for file-based storage
+    _ThrowError("Rename is not supported for file-based storage")
+
+  def Grow(self, amount):
+    """Grow the file
+
+    @param amount: the amount (in mebibytes) to grow with
+
+    """
+    # TODO: implement grow for file-based storage
+    _ThrowError("Grow not supported for file-based storage")
+

   def Attach(self):
     """Attach to an existing file.
 
   def Attach(self):
     """Attach to an existing file.
 

@@ -1847,9 +1929,11 @@ class FileStorage(BlockDev):
 DEV_MAP = {
   constants.LD_LV: LogicalVolume,
   constants.LD_DRBD8: DRBD8,
 DEV_MAP = {
   constants.LD_LV: LogicalVolume,
   constants.LD_DRBD8: DRBD8,

-  constants.LD_FILE: FileStorage,

   }
 
   }
 

+if constants.ENABLE_FILE_STORAGE:
+  DEV_MAP[constants.LD_FILE] = FileStorage
+

 
 def FindDevice(dev_type, unique_id, children, size):
   """Search for an existing, assembled device.
 
 def FindDevice(dev_type, unique_id, children, size):
   """Search for an existing, assembled device.