diff --git a/lib/bdev.py b/lib/bdev.py
index b2212356bfc5a4936677ca8bf8cff00f4829e2c5..080880cafa017992cbfb7a162b6b12441f84fc1d 100644
--- a/lib/bdev.py
+++ b/lib/bdev.py
@@ -38,12 +38,20 @@ from ganeti import objects
from ganeti import compat
from ganeti import netutils
from ganeti import pathutils
+from ganeti import serializer
# Size of reads in _CanReadDevice
_DEVICE_READ_SIZE = 128 * 1024
+class RbdShowmappedJsonError(Exception):
+ """`rbd showmmapped' JSON formatting error Exception class.
+
+ """
+ pass
+
+
def _IgnoreError(fn, *args, **kwargs):
"""Executes the given function, ignoring BlockDeviceErrors.
@@ -2726,14 +2734,7 @@ class RADOSBlockDevice(BlockDev):
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:
- _ThrowError("rbd showmapped failed (%s): %s",
- result.fail_reason, result.output)
-
- rbd_dev = self._ParseRbdShowmappedOutput(result.output, name)
-
+ rbd_dev = self._VolumeToBlockdev(pool, name)
if rbd_dev:
# The mapping exists. Return it.
return rbd_dev
@@ -2746,14 +2747,7 @@ class RADOSBlockDevice(BlockDev):
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)
-
+ rbd_dev = self._VolumeToBlockdev(pool, 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)
@@ -2761,16 +2755,93 @@ class RADOSBlockDevice(BlockDev):
# The device was successfully mapped. Return it.
return rbd_dev
+ @classmethod
+ def _VolumeToBlockdev(cls, pool, volume_name):
+ """Do the 'volume name'-to-'rbd block device' resolving.
+
+ @type pool: string
+ @param pool: RADOS pool to use
+ @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
+
+ """
+ try:
+ # Newer versions of the rbd tool support json output formatting. Use it
+ # if available.
+ showmap_cmd = [
+ constants.RBD_CMD,
+ "showmapped",
+ "-p",
+ pool,
+ "--format",
+ "json"
+ ]
+ result = utils.RunCmd(showmap_cmd)
+ if result.failed:
+ logging.error("rbd JSON output formatting returned error (%s): %s,"
+ "falling back to plain output parsing",
+ result.fail_reason, result.output)
+ raise RbdShowmappedJsonError
+
+ return cls._ParseRbdShowmappedJson(result.output, volume_name)
+ except RbdShowmappedJsonError:
+ # For older versions of rbd, we have to parse the plain / text output
+ # manually.
+ showmap_cmd = [constants.RBD_CMD, "showmapped", "-p", pool]
+ result = utils.RunCmd(showmap_cmd)
+ if result.failed:
+ _ThrowError("rbd showmapped failed (%s): %s",
+ result.fail_reason, result.output)
+
+ return cls._ParseRbdShowmappedPlain(result.output, volume_name)
+
+ @staticmethod
+ def _ParseRbdShowmappedJson(output, volume_name):
+ """Parse the json output of `rbd showmapped'.
+
+ This method parses the json 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 json 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
+
+ """
+ try:
+ devices = serializer.LoadJson(output)
+ except ValueError, err:
+ _ThrowError("Unable to parse JSON data: %s" % err)
+
+ rbd_dev = None
+ for d in devices.values(): # pylint: disable=E1103
+ try:
+ name = d["name"]
+ except KeyError:
+ _ThrowError("'name' key missing from json object %s", devices)
+
+ if name == volume_name:
+ if rbd_dev is not None:
+ _ThrowError("rbd volume %s is mapped more than once", volume_name)
+
+ rbd_dev = d["device"]
+
+ return rbd_dev
+
@staticmethod
- def _ParseRbdShowmappedOutput(output, volume_name):
- """Parse the output of `rbd showmapped'.
+ def _ParseRbdShowmappedPlain(output, volume_name):
+ """Parse the (plain / text) 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'
+ @param output: the plain text 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
@@ -2781,30 +2852,31 @@ class RADOSBlockDevice(BlockDev):
volumefield = 2
devicefield = 4
- field_sep = "\t"
-
lines = output.splitlines()
- splitted_lines = map(lambda l: l.split(field_sep), lines)
- # Check empty output.
+ # Try parsing the new output format (ceph >= 0.55).
+ splitted_lines = map(lambda l: l.split(), lines)
+
+ # Check for empty output.
if not splitted_lines:
- _ThrowError("rbd showmapped returned empty output")
+ return None
- # Check showmapped header line, to determine number of fields.
+ # Check showmapped output, 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)
+ # Parsing the new format failed. Fallback to parsing the old output
+ # format (< 0.55).
+ splitted_lines = map(lambda l: l.split("\t"), lines)
+ if field_cnt != allfields:
+ _ThrowError("Cannot parse rbd showmapped output 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)
+ _ThrowError("rbd volume %s mapped more than once", volume_name)
if matched_lines:
# rbd block device found. Return it.
@@ -2845,13 +2917,7 @@ class RADOSBlockDevice(BlockDev):
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:
- _ThrowError("rbd showmapped failed [during unmap](%s): %s",
- result.fail_reason, result.output)
-
- rbd_dev = self._ParseRbdShowmappedOutput(result.output, name)
+ rbd_dev = self._VolumeToBlockdev(pool, name)
if rbd_dev:
# The mapping exists. Unmap the rbd device.