cloud-init/cloudinit/config/cc_disk_setup.py

797 lines
25 KiB
Python

# vi: ts=4 expandtab
#
# Copyright (C) 2009-2010 Canonical Ltd.
# Copyright (C) 2012 Hewlett-Packard Development Company, L.P.
#
# Author: Ben Howard <ben.howard@canonical.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 3, as
# published by the Free Software Foundation.
#
# 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/>.
from cloudinit.settings import PER_INSTANCE
from cloudinit import util
import logging
import os
import shlex
frequency = PER_INSTANCE
# Define the commands to use
UDEVADM_CMD = util.which('udevadm')
SFDISK_CMD = util.which("sfdisk")
LSBLK_CMD = util.which("lsblk")
BLKID_CMD = util.which("blkid")
BLKDEV_CMD = util.which("blockdev")
WIPEFS_CMD = util.which("wipefs")
LOG = logging.getLogger(__name__)
def handle(_name, cfg, cloud, log, _args):
"""
See doc/examples/cloud-config_disk-setup.txt for documentation on the
format.
"""
disk_setup = cfg.get("disk_setup")
if isinstance(disk_setup, dict):
update_disk_setup_devices(disk_setup, cloud.device_name_to_device)
log.debug("Partitioning disks: %s", str(disk_setup))
for disk, definition in disk_setup.items():
if not isinstance(definition, dict):
log.warn("Invalid disk definition for %s" % disk)
continue
try:
log.debug("Creating new partition table/disk")
util.log_time(logfunc=LOG.debug,
msg="Creating partition on %s" % disk,
func=mkpart, args=(disk, definition))
except Exception as e:
util.logexc(LOG, "Failed partitioning operation\n%s" % e)
fs_setup = cfg.get("fs_setup")
if isinstance(fs_setup, list):
log.debug("setting up filesystems: %s", str(fs_setup))
update_fs_setup_devices(fs_setup, cloud.device_name_to_device)
for definition in fs_setup:
if not isinstance(definition, dict):
log.warn("Invalid file system definition: %s" % definition)
continue
try:
log.debug("Creating new filesystem.")
device = definition.get('device')
util.log_time(logfunc=LOG.debug,
msg="Creating fs for %s" % device,
func=mkfs, args=(definition,))
except Exception as e:
util.logexc(LOG, "Failed during filesystem operation\n%s" % e)
def update_disk_setup_devices(disk_setup, tformer):
# update 'disk_setup' dictionary anywhere were a device may occur
# update it with the response from 'tformer'
for origname in disk_setup.keys():
transformed = tformer(origname)
if transformed is None or transformed == origname:
continue
if transformed in disk_setup:
LOG.info("Replacing %s in disk_setup for translation of %s",
origname, transformed)
del disk_setup[transformed]
disk_setup[transformed] = disk_setup[origname]
disk_setup[transformed]['_origname'] = origname
del disk_setup[origname]
LOG.debug("updated disk_setup device entry '%s' to '%s'",
origname, transformed)
def update_fs_setup_devices(disk_setup, tformer):
# update 'fs_setup' dictionary anywhere were a device may occur
# update it with the response from 'tformer'
for definition in disk_setup:
if not isinstance(definition, dict):
LOG.warn("entry in disk_setup not a dict: %s", definition)
continue
origname = definition.get('device')
if origname is None:
continue
transformed = None
if len(origname.split('.')) > 1:
# this maps ephemeralX.Y to a proper disk name. For example,
# if the origname is 'ephemeral0.1' and transformed is /dev/sdb
# then the returned device will be /dev/sdb1 _if_ /dev/sdb1 exists
# otherwise NONE
base_name = origname.split('.')[0]
tformed = tformer(base_name)
LOG.info("base device for %s is %s" % (origname, tformed))
transformed = util.map_device_alias(tformed, alias=origname)
LOG.info("%s is mapped to %s" % (origname, transformed))
else:
transformed = tformer(origname)
if transformed is None or transformed == origname:
continue
LOG.info("Mapped %s to physical device %s" % (origname, transformed))
definition['_origname'] = origname
definition['device'] = transformed
def value_splitter(values, start=None):
"""
Returns the key/value pairs of output sent as string
like: FOO='BAR' HOME='127.0.0.1'
"""
_values = shlex.split(values)
if start:
_values = _values[start:]
for key, value in [x.split('=') for x in _values]:
yield key, value
def device_type(device):
"""
Return the device type of the device by calling lsblk.
"""
lsblk_cmd = [LSBLK_CMD, '--pairs', '--nodeps', '--out', 'NAME,TYPE',
device]
info = None
try:
info, _err = util.subp(lsblk_cmd)
except Exception as e:
raise Exception("Failed during disk check for %s\n%s" % (device, e))
for key, value in value_splitter(info):
if key.lower() == "type":
return value.lower()
return None
def is_device_valid(name, partition=False):
"""
Check if the device is a valid device.
"""
d_type = ""
try:
d_type = device_type(name)
except:
LOG.warn("Query against device %s failed" % name)
return False
if partition and d_type == 'part':
return True
elif not partition and d_type == 'disk':
return True
return False
def check_fs(device):
"""
Check if the device has a filesystem on it
Output of blkid is generally something like:
/dev/sda: LABEL="Backup500G" UUID="..." TYPE="ext4"
Return values are device, label, type, uuid
"""
out, label, fs_type, uuid = None, None, None, None
blkid_cmd = [BLKID_CMD, '-c', '/dev/null', device]
try:
out, _err = util.subp(blkid_cmd, rcs=[0, 2])
except Exception as e:
raise Exception("Failed during disk check for %s\n%s" % (device, e))
if out:
if len(out.splitlines()) == 1:
for key, value in value_splitter(out, start=1):
if key.lower() == 'label':
label = value
elif key.lower() == 'type':
fs_type = value
elif key.lower() == 'uuid':
uuid = value
return label, fs_type, uuid
def is_filesystem(device):
"""
Returns true if the device has a file system.
"""
_, fs_type, _ = check_fs(device)
return fs_type
def enumerate_disk(device):
"""
Enumerate the elements of a child device. Return a dict of name,
type, fstype, and label
"""
lsblk_cmd = [LSBLK_CMD, '--pairs', '--out', 'NAME,TYPE,FSTYPE,LABEL',
device]
info = None
try:
info, _err = util.subp(lsblk_cmd)
except Exception as e:
raise Exception("Failed during disk check for %s\n%s" % (device, e))
parts = [x for x in (info.strip()).splitlines() if len(x.split()) > 0]
for part in parts:
d = {'name': None,
'type': None,
'fstype': None,
'label': None,
}
for key, value in value_splitter(part):
d[key.lower()] = value
yield d
def find_device_node(device, fs_type=None, label=None, valid_targets=None,
label_match=True, replace_fs=None):
"""
Find a device that is either matches the spec, or the first
The return is value is (<device>, <bool>) where the device is the
device to use and the bool is whether the device matches the
fs_type and label.
Note: This works with GPT partition tables!
"""
# label of None is same as no label
if label is None:
label = ""
if not valid_targets:
valid_targets = ['disk', 'part']
raw_device_used = False
for d in enumerate_disk(device):
if d['fstype'] == replace_fs and label_match is False:
# We found a device where we want to replace the FS
return ('/dev/%s' % d['name'], False)
if (d['fstype'] == fs_type and
((label_match and d['label'] == label) or not label_match)):
# If we find a matching device, we return that
return ('/dev/%s' % d['name'], True)
if d['type'] in valid_targets:
if d['type'] != 'disk' or d['fstype']:
raw_device_used = True
if d['type'] == 'disk':
# Skip the raw disk, its the default
pass
elif not d['fstype']:
return ('/dev/%s' % d['name'], False)
if not raw_device_used:
return (device, False)
LOG.warn("Failed to find device during available device search.")
return (None, False)
def is_disk_used(device):
"""
Check if the device is currently used. Returns false if there
is no filesystem found on the disk.
"""
lsblk_cmd = [LSBLK_CMD, '--pairs', '--out', 'NAME,TYPE',
device]
info = None
try:
info, _err = util.subp(lsblk_cmd)
except Exception as e:
# if we error out, we can't use the device
util.logexc(LOG,
"Error checking for filesystem on %s\n%s" % (device, e))
return True
# If there is any output, then the device has something
if len(info.splitlines()) > 1:
return True
return False
def get_hdd_size(device):
"""
Returns the hard disk size.
This works with any disk type, including GPT.
"""
size_cmd = [SFDISK_CMD, '--show-size', device]
size = None
try:
size, _err = util.subp(size_cmd)
except Exception as e:
raise Exception("Failed to get %s size\n%s" % (device, e))
return int(size.strip())
def get_dyn_func(*args):
"""
Call the appropriate function.
The first value is the template for function name
The second value is the template replacement
The remain values are passed to the function
For example: get_dyn_func("foo_%s", 'bar', 1, 2, 3,)
would call "foo_bar" with args of 1, 2, 3
"""
if len(args) < 2:
raise Exception("Unable to determine dynamic funcation name")
func_name = (args[0] % args[1])
func_args = args[2:]
try:
if func_args:
return globals()[func_name](*func_args)
else:
return globals()[func_name]
except KeyError:
raise Exception("No such function %s to call!" % func_name)
def check_partition_mbr_layout(device, layout):
"""
Returns true if the partition layout matches the one on the disk
Layout should be a list of values. At this time, this only
verifies that the number of partitions and their labels is correct.
"""
read_parttbl(device)
prt_cmd = [SFDISK_CMD, "-l", device]
try:
out, _err = util.subp(prt_cmd, data="%s\n" % layout)
except Exception as e:
raise Exception("Error running partition command on %s\n%s" % (
device, e))
found_layout = []
for line in out.splitlines():
_line = line.split()
if len(_line) == 0:
continue
if device in _line[0]:
# We don't understand extended partitions yet
if _line[-1].lower() in ['extended', 'empty']:
continue
# Find the partition types
type_label = None
for x in sorted(range(1, len(_line)), reverse=True):
if _line[x].isdigit() and _line[x] != '/':
type_label = _line[x]
break
found_layout.append(type_label)
if isinstance(layout, bool):
# if we are using auto partitioning, or "True" be happy
# if a single partition exists.
if layout and len(found_layout) >= 1:
return True
return False
else:
if len(found_layout) != len(layout):
return False
else:
# This just makes sure that the number of requested
# partitions and the type labels are right
for x in range(1, len(layout) + 1):
if isinstance(layout[x - 1], tuple):
_, part_type = layout[x]
if int(found_layout[x]) != int(part_type):
return False
return True
return False
def check_partition_layout(table_type, device, layout):
"""
See if the partition lay out matches.
This is future a future proofing function. In order
to add support for other disk layout schemes, add a
function called check_partition_%s_layout
"""
return get_dyn_func("check_partition_%s_layout", table_type, device,
layout)
def get_partition_mbr_layout(size, layout):
"""
Calculate the layout of the partition table. Partition sizes
are defined as percentage values or a tuple of percentage and
partition type.
For example:
[ 33, [66: 82] ]
Defines the first partition to be a size of 1/3 the disk,
while the remaining 2/3's will be of type Linux Swap.
"""
if not isinstance(layout, list) and isinstance(layout, bool):
# Create a single partition
return "0,"
if ((len(layout) == 0 and isinstance(layout, list)) or
not isinstance(layout, list)):
raise Exception("Partition layout is invalid")
last_part_num = len(layout)
if last_part_num > 4:
raise Exception("Only simply partitioning is allowed.")
part_definition = []
part_num = 0
for part in layout:
part_type = 83 # Default to Linux
percent = part
part_num += 1
if isinstance(part, list):
if len(part) != 2:
raise Exception("Partition was incorrectly defined: %s" % part)
percent, part_type = part
part_size = int((float(size) * (float(percent) / 100)) / 1024)
if part_num == last_part_num:
part_definition.append(",,%s" % part_type)
else:
part_definition.append(",%s,%s" % (part_size, part_type))
sfdisk_definition = "\n".join(part_definition)
if len(part_definition) > 4:
raise Exception("Calculated partition definition is too big\n%s" %
sfdisk_definition)
return sfdisk_definition
def purge_disk_ptable(device):
# wipe the first and last megabyte of a disk (or file)
# gpt stores partition table both at front and at end.
start_len = 1024 * 1024
end_len = 1024 * 1024
with open(device, "rb+") as fp:
fp.write('\0' * (start_len))
fp.seek(-end_len, os.SEEK_END)
fp.write('\0' * end_len)
fp.flush()
read_parttbl(device)
def purge_disk(device):
"""
Remove parition table entries
"""
# wipe any file systems first
for d in enumerate_disk(device):
if d['type'] not in ["disk", "crypt"]:
wipefs_cmd = [WIPEFS_CMD, "--all", "/dev/%s" % d['name']]
try:
LOG.info("Purging filesystem on /dev/%s" % d['name'])
util.subp(wipefs_cmd)
except Exception:
raise Exception("Failed FS purge of /dev/%s" % d['name'])
purge_disk_ptable(device)
def get_partition_layout(table_type, size, layout):
"""
Call the appropriate function for creating the table
definition. Returns the table definition
This is a future proofing function. To add support for
other layouts, simply add a "get_partition_%s_layout"
function.
"""
return get_dyn_func("get_partition_%s_layout", table_type, size, layout)
def read_parttbl(device):
"""
Use partprobe instead of 'udevadm'. Partprobe is the only
reliable way to probe the partition table.
"""
blkdev_cmd = [BLKDEV_CMD, '--rereadpt', device]
udev_cmd = [UDEVADM_CMD, 'settle']
try:
util.subp(udev_cmd)
util.subp(blkdev_cmd)
util.subp(udev_cmd)
except Exception as e:
util.logexc(LOG, "Failed reading the partition table %s" % e)
def exec_mkpart_mbr(device, layout):
"""
Break out of mbr partition to allow for future partition
types, i.e. gpt
"""
# Create the partitions
prt_cmd = [SFDISK_CMD, "--Linux", "-uM", device]
try:
util.subp(prt_cmd, data="%s\n" % layout)
except Exception as e:
raise Exception("Failed to partition device %s\n%s" % (device, e))
read_parttbl(device)
def exec_mkpart(table_type, device, layout):
"""
Fetches the function for creating the table type.
This allows to dynamically find which function to call.
Paramaters:
table_type: type of partition table to use
device: the device to work on
layout: layout definition specific to partition table
"""
return get_dyn_func("exec_mkpart_%s", table_type, device, layout)
def mkpart(device, definition):
"""
Creates the partition table.
Parameters:
definition: dictionary describing how to create the partition.
The following are supported values in the dict:
overwrite: Should the partition table be created regardless
of any pre-exisiting data?
layout: the layout of the partition table
table_type: Which partition table to use, defaults to MBR
device: the device to work on.
"""
LOG.debug("Checking values for %s definition" % device)
overwrite = definition.get('overwrite', False)
layout = definition.get('layout', False)
table_type = definition.get('table_type', 'mbr')
# Check if the default device is a partition or not
LOG.debug("Checking against default devices")
if (isinstance(layout, bool) and not layout) or not layout:
LOG.debug("Device is not to be partitioned, skipping")
return # Device is not to be partitioned
# This prevents you from overwriting the device
LOG.debug("Checking if device %s is a valid device", device)
if not is_device_valid(device):
raise Exception("Device %s is not a disk device!", device)
# Remove the partition table entries
if isinstance(layout, str) and layout.lower() == "remove":
LOG.debug("Instructed to remove partition table entries")
purge_disk(device)
return
LOG.debug("Checking if device layout matches")
if check_partition_layout(table_type, device, layout):
LOG.debug("Device partitioning layout matches")
return True
LOG.debug("Checking if device is safe to partition")
if not overwrite and (is_disk_used(device) or is_filesystem(device)):
LOG.debug("Skipping partitioning on configured device %s" % device)
return
LOG.debug("Checking for device size")
device_size = get_hdd_size(device)
LOG.debug("Calculating partition layout")
part_definition = get_partition_layout(table_type, device_size, layout)
LOG.debug(" Layout is: %s" % part_definition)
LOG.debug("Creating partition table on %s", device)
exec_mkpart(table_type, device, part_definition)
LOG.debug("Partition table created for %s", device)
def lookup_force_flag(fs):
"""
A force flag might be -F or -F, this look it up
"""
flags = {'ext': '-F',
'btrfs': '-f',
'xfs': '-f',
'reiserfs': '-f',
}
if 'ext' in fs.lower():
fs = 'ext'
if fs.lower() in flags:
return flags[fs]
LOG.warn("Force flag for %s is unknown." % fs)
return ''
def mkfs(fs_cfg):
"""
Create a file system on the device.
label: defines the label to use on the device
fs_cfg: defines how the filesystem is to look
The following values are required generally:
device: which device or cloud defined default_device
filesystem: which file system type
overwrite: indiscriminately create the file system
partition: when device does not define a partition,
setting this to a number will mean
device + partition. When set to 'auto', the
first free device or the first device which
matches both label and type will be used.
'any' means the first filesystem that matches
on the device.
When 'cmd' is provided then no other parameter is required.
"""
label = fs_cfg.get('label')
device = fs_cfg.get('device')
partition = str(fs_cfg.get('partition', 'any'))
fs_type = fs_cfg.get('filesystem')
fs_cmd = fs_cfg.get('cmd', [])
fs_opts = fs_cfg.get('extra_opts', [])
fs_replace = fs_cfg.get('replace_fs', False)
overwrite = fs_cfg.get('overwrite', False)
# This allows you to define the default ephemeral or swap
LOG.debug("Checking %s against default devices", device)
if not partition or partition.isdigit():
# Handle manual definition of partition
if partition.isdigit():
device = "%s%s" % (device, partition)
LOG.debug("Manual request of partition %s for %s",
partition, device)
# Check to see if the fs already exists
LOG.debug("Checking device %s", device)
check_label, check_fstype, _ = check_fs(device)
LOG.debug("Device %s has %s %s", device, check_label, check_fstype)
if check_label == label and check_fstype == fs_type:
LOG.debug("Existing file system found at %s", device)
if not overwrite:
LOG.debug("Device %s has required file system", device)
return
else:
LOG.warn("Destroying filesystem on %s", device)
else:
LOG.debug("Device %s is cleared for formating", device)
elif partition and str(partition).lower() in ('auto', 'any'):
# For auto devices, we match if the filesystem does exist
odevice = device
LOG.debug("Identifying device to create %s filesytem on", label)
# any mean pick the first match on the device with matching fs_type
label_match = True
if partition.lower() == 'any':
label_match = False
device, reuse = find_device_node(device, fs_type=fs_type, label=label,
label_match=label_match,
replace_fs=fs_replace)
LOG.debug("Automatic device for %s identified as %s", odevice, device)
if reuse:
LOG.debug("Found filesystem match, skipping formating.")
return
if not reuse and fs_replace and device:
LOG.debug("Replacing file system on %s as instructed." % device)
if not device:
LOG.debug("No device aviable that matches request. "
"Skipping fs creation for %s", fs_cfg)
return
elif not partition or str(partition).lower() == 'none':
LOG.debug("Using the raw device to place filesystem %s on" % label)
else:
LOG.debug("Error in device identification handling.")
return
LOG.debug("File system %s will be created on %s", label, device)
# Make sure the device is defined
if not device:
LOG.warn("Device is not known: %s", device)
return
# Check that we can create the FS
if not (fs_type or fs_cmd):
raise Exception("No way to create filesystem '%s'. fs_type or fs_cmd "
"must be set.", label)
# Create the commands
if fs_cmd:
fs_cmd = fs_cfg['cmd'] % {'label': label,
'filesystem': fs_type,
'device': device,
}
else:
# Find the mkfs command
mkfs_cmd = util.which("mkfs.%s" % fs_type)
if not mkfs_cmd:
mkfs_cmd = util.which("mk%s" % fs_type)
if not mkfs_cmd:
LOG.warn("Cannot create fstype '%s'. No mkfs.%s command", fs_type,
fs_type)
return
fs_cmd = [mkfs_cmd, device]
if label:
fs_cmd.extend(["-L", label])
# File systems that support the -F flag
if not fs_cmd and (overwrite or device_type(device) == "disk"):
fs_cmd.append(lookup_force_flag(fs_type))
# Add the extends FS options
if fs_opts:
fs_cmd.extend(fs_opts)
LOG.debug("Creating file system %s on %s", label, device)
LOG.debug(" Using cmd: %s", " ".join(fs_cmd))
try:
util.subp(fs_cmd)
except Exception as e:
raise Exception("Failed to exec of '%s':\n%s" % (fs_cmd, e))