qubes-installer-qubes-os/storage/udev.py
2011-01-18 04:24:57 -05:00

506 lines
16 KiB
Python

# udev.py
# Python module for querying the udev database for device information.
#
# Copyright (C) 2009 Red Hat, Inc.
#
# This copyrighted material is made available to anyone wishing to use,
# modify, copy, or redistribute it subject to the terms and conditions of
# the GNU General Public License v.2, or (at your option) any later version.
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY expressed or implied, including the implied warranties 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, write to the
# Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA. Any Red Hat trademarks that are incorporated in the
# source code or documentation are not subject to the GNU General Public
# License and may only be used or replicated with the express permission of
# Red Hat, Inc.
#
# Red Hat Author(s): Dave Lehman <dlehman@redhat.com>
#
import os
import iutil
from errors import *
from baseudev import *
import logging
log = logging.getLogger("storage")
def udev_resolve_devspec(devspec):
if not devspec:
return None
import devices as _devices
ret = None
for dev in udev_get_block_devices():
if devspec.startswith("LABEL="):
if udev_device_get_label(dev) == devspec[6:]:
ret = dev
break
elif devspec.startswith("UUID="):
if udev_device_get_uuid(dev) == devspec[5:]:
ret = dev
break
elif udev_device_get_name(dev) == _devices.devicePathToName(devspec):
ret = dev
break
else:
for link in dev["symlinks"]:
if devspec == link:
ret = dev
break
del _devices
if ret:
return udev_device_get_name(ret)
def udev_resolve_glob(glob):
import fnmatch
ret = []
if not glob:
return ret
for dev in udev_get_block_devices():
name = udev_device_get_name(dev)
if fnmatch.fnmatch(name, glob):
ret.append(name)
else:
for link in dev["symlinks"]:
if fnmatch.fnmatch(link, glob):
ret.append(name)
return ret
def udev_get_block_devices():
udev_settle()
entries = []
for path in udev_enumerate_block_devices():
entry = udev_get_block_device(path)
if entry:
if entry["name"].startswith("md"):
# mdraid is really braindead, when a device is stopped
# it is no longer usefull in anyway (and we should not
# probe it) yet it still sticks around, see bug rh523387
state = None
state_file = "/sys/%s/md/array_state" % entry["sysfs_path"]
if os.access(state_file, os.R_OK):
state = open(state_file).read().strip()
if state == "clear":
continue
entries.append(entry)
return entries
def __is_blacklisted_blockdev(dev_name):
"""Is this a blockdev we never want for an install?"""
if dev_name.startswith("loop") or dev_name.startswith("ram") or dev_name.startswith("fd"):
return True
if os.path.exists("/sys/class/block/%s/device/model" %(dev_name,)):
model = open("/sys/class/block/%s/device/model" %(dev_name,)).read()
for bad in ("IBM *STMF KERNEL", "SCEI Flash-5", "DGC LUNZ"):
if model.find(bad) != -1:
log.info("ignoring %s with model %s" %(dev_name, model))
return True
return False
def udev_enumerate_block_devices():
import os.path
return filter(lambda d: not __is_blacklisted_blockdev(os.path.basename(d)),
udev_enumerate_devices(deviceClass="block"))
def udev_get_block_device(sysfs_path):
dev = udev_get_device(sysfs_path)
if not dev or not dev.has_key("name"):
return None
else:
return dev
# These are functions for retrieving specific pieces of information from
# udev database entries.
def udev_device_get_name(udev_info):
""" Return the best name for a device based on the udev db data. """
return udev_info.get("DM_NAME", udev_info["name"])
def udev_device_get_format(udev_info):
""" Return a device's format type as reported by udev. """
return udev_info.get("ID_FS_TYPE")
def udev_device_get_uuid(udev_info):
""" Get the UUID from the device's format as reported by udev. """
md_uuid = udev_info.get("MD_UUID")
uuid = udev_info.get("ID_FS_UUID")
# we don't want to return the array's uuid as a member's uuid
if uuid and not md_uuid == uuid:
return udev_info.get("ID_FS_UUID")
def udev_device_get_label(udev_info):
""" Get the label from the device's format as reported by udev. """
return udev_info.get("ID_FS_LABEL")
def udev_device_is_dm(info):
""" Return True if the device is a device-mapper device. """
return info.has_key("DM_NAME")
def udev_device_is_md(info):
""" Return True if the device is a mdraid array device. """
# Don't identify partitions on mdraid arrays as raid arrays
if udev_device_is_partition(info):
return False
# isw raid set *members* have MD_METADATA set, but are not arrays!
return info.has_key("MD_METADATA") and \
info.get("ID_FS_TYPE") != "isw_raid_member"
def udev_device_is_cciss(info):
""" Return True if the device is a CCISS device. """
return udev_device_get_name(info).startswith("cciss")
def udev_device_is_dasd(info):
""" Return True if the device is a dasd device. """
devname = info.get("DEVNAME")
if devname:
return devname.startswith("dasd")
else:
return False
def udev_device_is_zfcp(info):
""" Return True if the device is a zfcp device. """
if info.get("DEVTYPE") != "disk":
return False
subsystem = "/sys" + info.get("sysfs_path")
while True:
topdir = os.path.realpath(os.path.dirname(subsystem))
driver = "%s/driver" % (topdir,)
if os.path.islink(driver):
subsystemname = os.path.basename(os.readlink(subsystem))
drivername = os.path.basename(os.readlink(driver))
if subsystemname == 'ccw' and drivername == 'zfcp':
return True
newsubsystem = os.path.dirname(topdir)
if newsubsystem == topdir:
break
subsystem = newsubsystem + "/subsystem"
return False
def udev_device_get_zfcp_attribute(info, attr=None):
""" Return the value of the specified attribute of the zfcp device. """
if not attr:
log.debug("udev_device_get_zfcp_attribute() called with attr=None")
return None
attribute = "/sys%s/device/%s" % (info.get("sysfs_path"), attr,)
attribute = os.path.realpath(attribute)
if not os.path.isfile(attribute):
log.warning("%s is not a valid zfcp attribute" % (attribute,))
return None
return open(attribute, "r").read().strip()
def udev_device_get_dasd_bus_id(info):
""" Return the CCW bus ID of the dasd device. """
return info.get("sysfs_path").split("/")[-3]
def udev_device_get_dasd_flag(info, flag=None):
""" Return the specified flag for the dasd device. """
if flag is None:
return None
path = "/sys" + info.get("sysfs_path") + "/device/" + flag
if not os.path.isfile(path):
return None
return open(path, 'r').read().strip()
def udev_device_is_cdrom(info):
""" Return True if the device is an optical drive. """
# FIXME: how can we differentiate USB drives from CD-ROM drives?
# -- USB drives also generate a sdX device.
return info.get("ID_CDROM") == "1"
def udev_device_is_disk(info):
""" Return True is the device is a disk. """
if udev_device_is_cdrom(info):
return False
has_range = os.path.exists("/sys/%s/range" % info['sysfs_path'])
return info.get("DEVTYPE") == "disk" or has_range
def udev_device_is_partition(info):
has_start = os.path.exists("/sys/%s/start" % info['sysfs_path'])
return info.get("DEVTYPE") == "partition" or has_start
def udev_device_get_serial(udev_info):
""" Get the serial number/UUID from the device as reported by udev. """
return udev_info.get("ID_SERIAL_SHORT", udev_info.get("ID_SERIAL"))
def udev_device_get_wwid(udev_info):
""" The WWID of a device is typically just its serial number, but with
colons in the name to make it more readable. """
serial = udev_device_get_serial(udev_info)
if serial and len(serial) == 32:
retval = ""
for i in range(0, 16):
retval += serial[i*2:i*2+2] + ":"
return retval[0:-1]
return ""
def udev_device_get_vendor(udev_info):
""" Get the vendor of the device as reported by udev. """
return udev_info.get("ID_VENDOR_FROM_DATABASE", udev_info.get("ID_VENDOR"))
def udev_device_get_model(udev_info):
""" Get the model of the device as reported by udev. """
return udev_info.get("ID_MODEL_FROM_DATABASE", udev_info.get("ID_MODEL"))
def udev_device_get_bus(udev_info):
""" Get the bus a device is connected to the system by. """
return udev_info.get("ID_BUS", "").upper()
def udev_device_get_path(info):
return info["ID_PATH"]
def udev_device_get_sysfs_path(info):
return info['sysfs_path']
def udev_device_get_major(info):
return int(info["MAJOR"])
def udev_device_get_minor(info):
return int(info["MINOR"])
def udev_device_get_md_level(info):
return info.get("MD_LEVEL")
def udev_device_get_md_devices(info):
return int(info["MD_DEVICES"])
def udev_device_get_md_uuid(info):
return info["MD_UUID"]
def udev_device_get_md_container(info):
return info.get("MD_CONTAINER")
def udev_device_get_md_name(info):
return info.get("MD_DEVNAME")
def udev_device_get_vg_name(info):
return info['LVM2_VG_NAME']
def udev_device_get_vg_uuid(info):
return info['LVM2_VG_UUID']
def udev_device_get_vg_size(info):
# lvm's decmial precision is not configurable, so we tell it to use
# KB and convert to MB here
return float(info['LVM2_VG_SIZE']) / 1024
def udev_device_get_vg_free(info):
# lvm's decmial precision is not configurable, so we tell it to use
# KB and convert to MB here
return float(info['LVM2_VG_FREE']) / 1024
def udev_device_get_vg_extent_size(info):
# lvm's decmial precision is not configurable, so we tell it to use
# KB and convert to MB here
return float(info['LVM2_VG_EXTENT_SIZE']) / 1024
def udev_device_get_vg_extent_count(info):
return int(info['LVM2_VG_EXTENT_COUNT'])
def udev_device_get_vg_free_extents(info):
return int(info['LVM2_VG_FREE_COUNT'])
def udev_device_get_vg_pv_count(info):
return int(info['LVM2_PV_COUNT'])
def udev_device_get_pv_pe_start(info):
# lvm's decmial precision is not configurable, so we tell it to use
# KB and convert to MB here
return float(info['LVM2_PE_START']) / 1024
def udev_device_get_lv_names(info):
names = info['LVM2_LV_NAME']
if not names:
names = []
elif not isinstance(names, list):
names = [names]
return names
def udev_device_get_lv_uuids(info):
uuids = info['LVM2_LV_UUID']
if not uuids:
uuids = []
elif not isinstance(uuids, list):
uuids = [uuids]
return uuids
def udev_device_get_lv_sizes(info):
# lvm's decmial precision is not configurable, so we tell it to use
# KB and convert to MB here
sizes = info['LVM2_LV_SIZE']
if not sizes:
sizes = []
elif not isinstance(sizes, list):
sizes = [sizes]
return [float(s) / 1024 for s in sizes]
def udev_device_get_lv_attr(info):
attr = info['LVM2_LV_ATTR']
if not attr:
attr = []
elif not isinstance(attr, list):
attr = [attr]
return attr
def udev_device_is_biosraid(info):
# Note that this function does *not* identify raid sets.
# Tests to see if device is parto of a dmraid set.
# dmraid and mdraid have the same ID_FS_USAGE string, ID_FS_TYPE has a
# string that describes the type of dmraid (isw_raid_member...), I don't
# want to maintain a list and mdraid's ID_FS_TYPE='linux_raid_member', so
# dmraid will be everything that is raid and not linux_raid_member
from formats.dmraid import DMRaidMember
from formats.mdraid import MDRaidMember
if info.has_key("ID_FS_TYPE") and \
(info["ID_FS_TYPE"] in DMRaidMember._udevTypes or \
info["ID_FS_TYPE"] in MDRaidMember._udevTypes) and \
info["ID_FS_TYPE"] != "linux_raid_member":
return True
return False
def udev_device_get_dmraid_partition_disk(info):
try:
p_index = info["DM_NAME"].rindex("p")
except (KeyError, AttributeError, ValueError):
return None
if not info["DM_NAME"][p_index+1:].isdigit():
return None
return info["DM_NAME"][:p_index]
def udev_device_is_dmraid_partition(info, devicetree):
diskname = udev_device_get_dmraid_partition_disk(info)
dmraid_devices = devicetree.getDevicesByType("dm-raid array")
for device in dmraid_devices:
if diskname == device.name:
return True
return False
def udev_device_is_multipath_partition(info, devicetree):
""" Return True if the device is a partition of a multipath device. """
if not udev_device_is_dm(info):
return False
if not info["DM_NAME"].startswith("mpath"):
return False
diskname = udev_device_get_dmraid_partition_disk(info)
if diskname is None:
return False
# this is sort of a lame check, but basically, if diskname gave us "mpath0"
# and we start with "mpath" but we're not "mpath0", then we must be
# "mpath0" plus some non-numeric crap.
if diskname != info["DM_NAME"]:
return True
return False
def udev_device_get_multipath_partition_disk(info):
""" Return True if the device is a partition of a multipath device. """
# XXX PJFIX This whole function is crap.
if not udev_device_is_dm(info):
return False
if not info["DM_NAME"].startswith("mpath"):
return False
diskname = udev_device_get_dmraid_partition_disk(info)
return diskname
def udev_device_is_multipath_member(info):
""" Return True if the device is part of a multipath. """
return info.get("ID_FS_TYPE") == "multipath_member"
def udev_device_get_multipath_name(info):
""" Return the name of the multipath that the device is a member of. """
if udev_device_is_multipath_member(info):
return info['ID_MPATH_NAME']
return None
# iscsi disks have ID_PATH in the form of:
# ip-${iscsi_address}:${iscsi_port}-iscsi-${iscsi_tgtname}-lun-${lun}
def udev_device_is_iscsi(info):
try:
path_components = udev_device_get_path(info).split("-")
if info["ID_BUS"] == "scsi" and len(path_components) >= 6 and \
path_components[0] == "ip" and path_components[2] == "iscsi":
return True
except KeyError:
pass
return False
def udev_device_get_iscsi_name(info):
path_components = udev_device_get_path(info).split("-")
# Tricky, the name itself contains atleast 1 - char
return "-".join(path_components[3:len(path_components)-2])
def udev_device_get_iscsi_address(info):
path_components = udev_device_get_path(info).split("-")
return path_components[1].split(":")[0]
def udev_device_get_iscsi_port(info):
path_components = udev_device_get_path(info).split("-")
return path_components[1].split(":")[1]
# fcoe disks have ID_PATH in the form of:
# pci-eth#-fc-${id}
# fcoe parts look like this:
# pci-eth#-fc-${id}-part#
def udev_device_is_fcoe(info):
try:
path_components = udev_device_get_path(info).split("-")
if info["ID_BUS"] == "scsi" and len(path_components) >= 4 and \
path_components[0] == "pci" and path_components[2] == "fc" and \
path_components[1][0:3] == "eth":
return True
except LookupError:
pass
return False
def udev_device_get_fcoe_nic(info):
path_components = udev_device_get_path(info).split("-")
return path_components[1]
def udev_device_get_fcoe_identifier(info):
path_components = udev_device_get_path(info).split("-")
return path_components[3]