qubes-installer-qubes-os/anaconda/storage/devicelibs/dm.py
2011-03-31 13:40:54 +02:00

131 lines
4.0 KiB
Python

#
# dm.py
# device-mapper functions
#
# Copyright (C) 2009 Red Hat, Inc. All rights reserved.
#
# 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
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# Author(s): Dave Lehman <dlehman@redhat.com>
#
import os
import block
import iutil
from ..errors import *
import gettext
_ = lambda x: gettext.ldgettext("anaconda", x)
import logging
log = logging.getLogger("storage")
def name_from_dm_node(dm_node):
name = block.getNameFromDmNode(dm_node)
if name is not None:
return name
st = os.stat("/dev/%s" % dm_node)
major = os.major(st.st_rdev)
minor = os.minor(st.st_rdev)
name = iutil.execWithCapture("dmsetup",
["info", "--columns",
"--noheadings", "-o", "name",
"-j", str(major), "-m", str(minor)],
stderr="/dev/tty5")
log.debug("name_from_dm(%s) returning '%s'" % (dm_node, name.strip()))
return name.strip()
def dm_node_from_name(map_name):
dm_node = block.getDmNodeFromName(map_name)
if dm_node is not None:
return dm_node
devnum = iutil.execWithCapture("dmsetup",
["info", "--columns",
"--noheadings",
"-o", "devno",
map_name],
stderr="/dev/tty5")
(major, sep, minor) = devnum.strip().partition(":")
if not sep:
raise DMError("dm device does not exist")
dm_node = "dm-%d" % int(minor)
log.debug("dm_node_from_name(%s) returning '%s'" % (map_name, dm_node))
return dm_node
def dm_is_multipath(info):
major = None
minor = None
if info.has_key('MAJOR'):
major = info['MAJOR']
elif info.has_key('DM_MAJOR'):
major = info['DM_MAJOR']
if info.has_key('MINOR'):
minor = info['MINOR']
elif info.has_key('DM_MINOR'):
minor = info['DM_MINOR']
if major is None or minor is None:
return False
for map in block.dm.maps():
dev = map.dev
if dev.major == int(major) and dev.minor == int(minor):
for table in map.table:
if table.type == 'multipath':
return True
def _get_backing_devnums_from_map(map_name):
ret = []
buf = iutil.execWithCapture("dmsetup",
["info", "--columns",
"--noheadings",
"-o", "devnos_used",
map_name],
stderr="/dev/tty5")
dev_nums = buf.split()
for dev_num in dev_nums:
(major, colon, minor) = dev_num.partition(":")
ret.append((int(major), int(minor)))
return ret
def get_backing_devnums(dm_node):
#dm_node = dm_node_from_name(map_name)
if not dm_node:
return None
top_dir = "/sys/block"
backing_devs = os.listdir("%s/%s/slaves/" % (top_dir, dm_node))
dev_nums = []
for backing_dev in backing_devs:
dev_num = open("%s/%s/dev" % (top_dir, backing_dev)).read().strip()
(_major, _minor) = dev_num.split(":")
dev_nums.append((int(_major), int(_minor)))
return dev_nums
def get_backing_devs_from_name(map_name):
dm_node = dm_node_from_name(map_name)
if not dm_node:
return None
slave_devs = os.listdir("/sys/block/virtual/%s" % dm_node)
return slave_devs