429 lines
16 KiB
Python
429 lines
16 KiB
Python
# (c) Copyright 2013 Hewlett-Packard Development Company, L.P.
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License"); you may
|
|
# not use this file except in compliance with the License. You may obtain
|
|
# a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
# License for the specific language governing permissions and limitations
|
|
# under the License.
|
|
|
|
"""Generic linux scsi subsystem and Multipath utilities.
|
|
|
|
Note, this is not iSCSI.
|
|
"""
|
|
import os
|
|
import re
|
|
import six
|
|
|
|
from oslo_concurrency import processutils as putils
|
|
from oslo_log import log as logging
|
|
|
|
from os_brick import exception
|
|
from os_brick import executor
|
|
from os_brick.i18n import _LI
|
|
from os_brick.i18n import _LW
|
|
from os_brick import utils
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
MULTIPATH_ERROR_REGEX = re.compile("\w{3} \d+ \d\d:\d\d:\d\d \|.*$")
|
|
MULTIPATH_WWID_REGEX = re.compile("\((?P<wwid>.+)\)")
|
|
MULTIPATH_DEVICE_ACTIONS = ['unchanged:', 'reject:', 'reload:',
|
|
'switchpg:', 'rename:', 'create:',
|
|
'resize:']
|
|
|
|
|
|
class LinuxSCSI(executor.Executor):
|
|
def __init__(self, root_helper, execute=putils.execute,
|
|
*args, **kwargs):
|
|
super(LinuxSCSI, self).__init__(root_helper, execute,
|
|
*args, **kwargs)
|
|
|
|
def echo_scsi_command(self, path, content):
|
|
"""Used to echo strings to scsi subsystem."""
|
|
|
|
args = ["-a", path]
|
|
kwargs = dict(process_input=content,
|
|
run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
self._execute('tee', *args, **kwargs)
|
|
|
|
def get_name_from_path(self, path):
|
|
"""Translates /dev/disk/by-path/ entry to /dev/sdX."""
|
|
|
|
name = os.path.realpath(path)
|
|
if name.startswith("/dev/"):
|
|
return name
|
|
else:
|
|
return None
|
|
|
|
def remove_scsi_device(self, device):
|
|
"""Removes a scsi device based upon /dev/sdX name."""
|
|
|
|
path = "/sys/block/%s/device/delete" % device.replace("/dev/", "")
|
|
if os.path.exists(path):
|
|
# flush any outstanding IO first
|
|
self.flush_device_io(device)
|
|
|
|
LOG.debug("Remove SCSI device %(device)s with %(path)s",
|
|
{'device': device, 'path': path})
|
|
self.echo_scsi_command(path, "1")
|
|
|
|
@utils.retry(exceptions=exception.VolumePathNotRemoved, retries=3,
|
|
backoff_rate=2)
|
|
def wait_for_volume_removal(self, volume_path):
|
|
"""This is used to ensure that volumes are gone."""
|
|
LOG.debug("Checking to see if SCSI volume %s has been removed.",
|
|
volume_path)
|
|
if os.path.exists(volume_path):
|
|
LOG.debug("%(path)s still exists.", {'path': volume_path})
|
|
raise exception.VolumePathNotRemoved(
|
|
volume_path=volume_path)
|
|
else:
|
|
LOG.debug("SCSI volume %s has been removed.", volume_path)
|
|
|
|
def get_device_info(self, device):
|
|
(out, _err) = self._execute('sg_scan', device, run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
dev_info = {'device': device, 'host': None,
|
|
'channel': None, 'id': None, 'lun': None}
|
|
if out:
|
|
line = out.strip()
|
|
line = line.replace(device + ": ", "")
|
|
info = line.split(" ")
|
|
|
|
for item in info:
|
|
if '=' in item:
|
|
pair = item.split('=')
|
|
dev_info[pair[0]] = pair[1]
|
|
elif 'scsi' in item:
|
|
dev_info['host'] = item.replace('scsi', '')
|
|
|
|
return dev_info
|
|
|
|
def get_scsi_wwn(self, path):
|
|
"""Read the WWN from page 0x83 value for a SCSI device."""
|
|
|
|
(out, _err) = self._execute('scsi_id', '--page', '0x83',
|
|
'--whitelisted', path,
|
|
run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
return out.strip()
|
|
|
|
def remove_multipath_device(self, device):
|
|
"""This removes LUNs associated with a multipath device
|
|
and the multipath device itself.
|
|
"""
|
|
|
|
LOG.debug("remove multipath device %s", device)
|
|
mpath_dev = self.find_multipath_device(device)
|
|
if mpath_dev:
|
|
self.flush_multipath_device(mpath_dev['id'])
|
|
devices = mpath_dev['devices']
|
|
LOG.debug("multipath LUNs to remove %s", devices)
|
|
for device in devices:
|
|
self.remove_scsi_device(device['device'])
|
|
|
|
def flush_device_io(self, device):
|
|
"""This is used to flush any remaining IO in the buffers."""
|
|
try:
|
|
LOG.debug("Flushing IO for device %s", device)
|
|
self._execute('blockdev', '--flushbufs', device, run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
except putils.ProcessExecutionError as exc:
|
|
LOG.warning(_LW("Failed to flush IO buffers prior to removing "
|
|
"device: %(code)s"), {'code': exc.exit_code})
|
|
|
|
def flush_multipath_device(self, device):
|
|
try:
|
|
LOG.debug("Flush multipath device %s", device)
|
|
self._execute('multipath', '-f', device, run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
except putils.ProcessExecutionError as exc:
|
|
LOG.warning(_LW("multipath call failed exit %(code)s"),
|
|
{'code': exc.exit_code})
|
|
|
|
def flush_multipath_devices(self):
|
|
try:
|
|
self._execute('multipath', '-F', run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
except putils.ProcessExecutionError as exc:
|
|
LOG.warning(_LW("multipath call failed exit %(code)s"),
|
|
{'code': exc.exit_code})
|
|
|
|
@utils.retry(exceptions=exception.VolumeDeviceNotFound)
|
|
def wait_for_path(self, volume_path):
|
|
"""Wait for a path to show up."""
|
|
LOG.debug("Checking to see if %s exists yet.",
|
|
volume_path)
|
|
if not os.path.exists(volume_path):
|
|
LOG.debug("%(path)s doesn't exists yet.", {'path': volume_path})
|
|
raise exception.VolumeDeviceNotFound(
|
|
device=volume_path)
|
|
else:
|
|
LOG.debug("%s has shown up.", volume_path)
|
|
|
|
@utils.retry(exceptions=exception.BlockDeviceReadOnly, retries=5)
|
|
def wait_for_rw(self, wwn, device_path):
|
|
"""Wait for block device to be Read-Write."""
|
|
LOG.debug("Checking to see if %s is read-only.",
|
|
device_path)
|
|
out, info = self._execute('lsblk', '-o', 'NAME,RO', '-l', '-n')
|
|
LOG.debug("lsblk output: %s", out)
|
|
blkdevs = out.splitlines()
|
|
for blkdev in blkdevs:
|
|
# Entries might look like:
|
|
#
|
|
# "3624a93709a738ed78583fd120013902b (dm-1) 1"
|
|
#
|
|
# or
|
|
#
|
|
# "sdd 0"
|
|
#
|
|
# We are looking for the first and last part of them. For FC
|
|
# multipath devices the name is in the format of '<WWN> (dm-<ID>)'
|
|
blkdev_parts = blkdev.split(' ')
|
|
ro = blkdev_parts[-1]
|
|
name = blkdev_parts[0]
|
|
|
|
# We must validate that all pieces of the dm-# device are rw,
|
|
# if some are still ro it can cause problems.
|
|
if wwn in name and int(ro) == 1:
|
|
LOG.debug("Block device %s is read-only", device_path)
|
|
self._execute('multipath', '-r', check_exit_code=[0, 1, 21],
|
|
run_as_root=True, root_helper=self._root_helper)
|
|
raise exception.BlockDeviceReadOnly(
|
|
device=device_path)
|
|
else:
|
|
LOG.debug("Block device %s is not read-only.", device_path)
|
|
|
|
def find_multipath_device_path(self, wwn):
|
|
"""Look for the multipath device file for a volume WWN.
|
|
|
|
Multipath devices can show up in several places on
|
|
a linux system.
|
|
|
|
1) When multipath friendly names are ON:
|
|
a device file will show up in
|
|
/dev/disk/by-id/dm-uuid-mpath-<WWN>
|
|
/dev/disk/by-id/dm-name-mpath<N>
|
|
/dev/disk/by-id/scsi-mpath<N>
|
|
/dev/mapper/mpath<N>
|
|
|
|
2) When multipath friendly names are OFF:
|
|
/dev/disk/by-id/dm-uuid-mpath-<WWN>
|
|
/dev/disk/by-id/scsi-<WWN>
|
|
/dev/mapper/<WWN>
|
|
|
|
"""
|
|
LOG.info(_LI("Find Multipath device file for volume WWN %(wwn)s"),
|
|
{'wwn': wwn})
|
|
# First look for the common path
|
|
wwn_dict = {'wwn': wwn}
|
|
path = "/dev/disk/by-id/dm-uuid-mpath-%(wwn)s" % wwn_dict
|
|
try:
|
|
self.wait_for_path(path)
|
|
return path
|
|
except exception.VolumeDeviceNotFound:
|
|
pass
|
|
|
|
# for some reason the common path wasn't found
|
|
# lets try the dev mapper path
|
|
path = "/dev/mapper/%(wwn)s" % wwn_dict
|
|
try:
|
|
self.wait_for_path(path)
|
|
return path
|
|
except exception.VolumeDeviceNotFound:
|
|
pass
|
|
|
|
# couldn't find a path
|
|
LOG.warning(_LW("couldn't find a valid multipath device path for "
|
|
"%(wwn)s"), wwn_dict)
|
|
return None
|
|
|
|
def find_multipath_device(self, device):
|
|
"""Discover multipath devices for a mpath device.
|
|
|
|
This uses the slow multipath -l command to find a
|
|
multipath device description, then screen scrapes
|
|
the output to discover the multipath device name
|
|
and it's devices.
|
|
|
|
"""
|
|
|
|
mdev = None
|
|
devices = []
|
|
out = None
|
|
try:
|
|
(out, _err) = self._execute('multipath', '-l', device,
|
|
run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
except putils.ProcessExecutionError as exc:
|
|
LOG.warning(_LW("multipath call failed exit %(code)s"),
|
|
{'code': exc.exit_code})
|
|
raise exception.CommandExecutionFailed(
|
|
cmd='multipath -l %s' % device)
|
|
|
|
if out:
|
|
lines = out.strip()
|
|
lines = lines.split("\n")
|
|
lines = [line for line in lines
|
|
if not re.match(MULTIPATH_ERROR_REGEX, line)]
|
|
if lines:
|
|
|
|
mdev_name = lines[0].split(" ")[0]
|
|
|
|
if mdev_name in MULTIPATH_DEVICE_ACTIONS:
|
|
mdev_name = lines[0].split(" ")[1]
|
|
|
|
mdev = '/dev/mapper/%s' % mdev_name
|
|
|
|
# Confirm that the device is present.
|
|
try:
|
|
os.stat(mdev)
|
|
except OSError:
|
|
LOG.warning(_LW("Couldn't find multipath device %s"),
|
|
mdev)
|
|
return None
|
|
|
|
wwid_search = MULTIPATH_WWID_REGEX.search(lines[0])
|
|
if wwid_search is not None:
|
|
mdev_id = wwid_search.group('wwid')
|
|
else:
|
|
mdev_id = mdev_name
|
|
|
|
LOG.debug("Found multipath device = %(mdev)s",
|
|
{'mdev': mdev})
|
|
device_lines = lines[3:]
|
|
for dev_line in device_lines:
|
|
if dev_line.find("policy") != -1:
|
|
continue
|
|
|
|
dev_line = dev_line.lstrip(' |-`')
|
|
dev_info = dev_line.split()
|
|
address = dev_info[0].split(":")
|
|
|
|
dev = {'device': '/dev/%s' % dev_info[1],
|
|
'host': address[0], 'channel': address[1],
|
|
'id': address[2], 'lun': address[3]
|
|
}
|
|
|
|
devices.append(dev)
|
|
|
|
if mdev is not None:
|
|
info = {"device": mdev,
|
|
"id": mdev_id,
|
|
"name": mdev_name,
|
|
"devices": devices}
|
|
return info
|
|
return None
|
|
|
|
def get_device_size(self, device):
|
|
"""Get the size in bytes of a volume."""
|
|
(out, _err) = self._execute('blockdev', '--getsize64',
|
|
device, run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
var = six.text_type(out.strip())
|
|
if var.isnumeric():
|
|
return int(var)
|
|
else:
|
|
return None
|
|
|
|
def multipath_reconfigure(self):
|
|
"""Issue a multipathd reconfigure.
|
|
|
|
When attachments come and go, the multipathd seems
|
|
to get lost and not see the maps. This causes
|
|
resize map to fail 100%. To overcome this we have
|
|
to issue a reconfigure prior to resize map.
|
|
"""
|
|
(out, _err) = self._execute('multipathd', 'reconfigure',
|
|
run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
return out
|
|
|
|
def multipath_resize_map(self, mpath_id):
|
|
"""Issue a multipath resize map on device.
|
|
|
|
This forces the multipath daemon to update it's
|
|
size information a particular multipath device.
|
|
"""
|
|
(out, _err) = self._execute('multipathd', 'resize', 'map', mpath_id,
|
|
run_as_root=True,
|
|
root_helper=self._root_helper)
|
|
return out
|
|
|
|
def extend_volume(self, volume_path):
|
|
"""Signal the SCSI subsystem to test for volume resize.
|
|
|
|
This function tries to signal the local system's kernel
|
|
that an already attached volume might have been resized.
|
|
"""
|
|
LOG.debug("extend volume %s", volume_path)
|
|
|
|
device = self.get_device_info(volume_path)
|
|
LOG.debug("Volume device info = %s", device)
|
|
device_id = ("%(host)s:%(channel)s:%(id)s:%(lun)s" %
|
|
{'host': device['host'],
|
|
'channel': device['channel'],
|
|
'id': device['id'],
|
|
'lun': device['lun']})
|
|
|
|
scsi_path = ("/sys/bus/scsi/drivers/sd/%(device_id)s" %
|
|
{'device_id': device_id})
|
|
|
|
size = self.get_device_size(volume_path)
|
|
LOG.debug("Starting size: %s", size)
|
|
|
|
# now issue the device rescan
|
|
rescan_path = "%(scsi_path)s/rescan" % {'scsi_path': scsi_path}
|
|
self.echo_scsi_command(rescan_path, "1")
|
|
new_size = self.get_device_size(volume_path)
|
|
LOG.debug("volume size after scsi device rescan %s", new_size)
|
|
|
|
scsi_wwn = self.get_scsi_wwn(volume_path)
|
|
mpath_device = self.find_multipath_device_path(scsi_wwn)
|
|
if mpath_device:
|
|
# Force a reconfigure so that resize works
|
|
self.multipath_reconfigure()
|
|
|
|
size = self.get_device_size(mpath_device)
|
|
LOG.info(_LI("mpath(%(device)s) current size %(size)s"),
|
|
{'device': mpath_device, 'size': size})
|
|
result = self.multipath_resize_map(scsi_wwn)
|
|
if 'fail' in result:
|
|
msg = (_LI("Multipathd failed to update the size mapping of "
|
|
"multipath device %(scsi_wwn)s volume %(volume)s") %
|
|
{'scsi_wwn': scsi_wwn, 'volume': volume_path})
|
|
LOG.error(msg)
|
|
return None
|
|
|
|
new_size = self.get_device_size(mpath_device)
|
|
LOG.info(_LI("mpath(%(device)s) new size %(size)s"),
|
|
{'device': mpath_device, 'size': new_size})
|
|
return new_size
|
|
else:
|
|
return new_size
|
|
|
|
def process_lun_id(self, lun_ids):
|
|
if isinstance(lun_ids, list):
|
|
processed = []
|
|
for x in lun_ids:
|
|
x = self._format_lun_id(x)
|
|
processed.append(x)
|
|
else:
|
|
processed = self._format_lun_id(lun_ids)
|
|
return processed
|
|
|
|
def _format_lun_id(self, lun_id):
|
|
if lun_id < 256:
|
|
return lun_id
|
|
else:
|
|
return ("0x%04x%04x00000000" %
|
|
(lun_id & 0xffff, lun_id >> 16 & 0xffff))
|