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Diffstat (limited to 'src/ceph-volume/ceph_volume/api/lvm.py')
| -rw-r--r-- | src/ceph-volume/ceph_volume/api/lvm.py | 1136 |
1 files changed, 1136 insertions, 0 deletions
diff --git a/src/ceph-volume/ceph_volume/api/lvm.py b/src/ceph-volume/ceph_volume/api/lvm.py new file mode 100644 index 00000000..30362f1b --- /dev/null +++ b/src/ceph-volume/ceph_volume/api/lvm.py @@ -0,0 +1,1136 @@ +""" +API for CRUD lvm tag operations. Follows the Ceph LVM tag naming convention +that prefixes tags with ``ceph.`` and uses ``=`` for assignment, and provides +set of utilities for interacting with LVM. +""" +import logging +import os +import uuid +from itertools import repeat +from math import floor +from ceph_volume import process, util +from ceph_volume.exceptions import SizeAllocationError + +logger = logging.getLogger(__name__) + + +def convert_filters_to_str(filters): + """ + Convert filter args from dictionary to following format - + filters={filter_name=filter_val,...} + """ + if not filters: + return filters + + filter_arg = '' + for k, v in filters.items(): + filter_arg += k + '=' + v + ',' + # get rid of extra comma at the end + filter_arg = filter_arg[:len(filter_arg) - 1] + + return filter_arg + + +def convert_tags_to_str(tags): + """ + Convert tags from dictionary to following format - + tags={tag_name=tag_val,...} + """ + if not tags: + return tags + + tag_arg = 'tags={' + for k, v in tags.items(): + tag_arg += k + '=' + v + ',' + # get rid of extra comma at the end + tag_arg = tag_arg[:len(tag_arg) - 1] + '}' + + return tag_arg + + +def make_filters_lvmcmd_ready(filters, tags): + """ + Convert filters (including tags) from dictionary to following format - + filter_name=filter_val...,tags={tag_name=tag_val,...} + + The command will look as follows = + lvs -S filter_name=filter_val...,tags={tag_name=tag_val,...} + """ + filters = convert_filters_to_str(filters) + tags = convert_tags_to_str(tags) + + if filters and tags: + return filters + ',' + tags + if filters and not tags: + return filters + if not filters and tags: + return tags + else: + return '' + + +def _output_parser(output, fields): + """ + Newer versions of LVM allow ``--reportformat=json``, but older versions, + like the one included in Xenial do not. LVM has the ability to filter and + format its output so we assume the output will be in a format this parser + can handle (using ';' as a delimiter) + + :param fields: A string, possibly using ',' to group many items, as it + would be used on the CLI + :param output: The CLI output from the LVM call + """ + field_items = fields.split(',') + report = [] + for line in output: + # clear the leading/trailing whitespace + line = line.strip() + + # remove the extra '"' in each field + line = line.replace('"', '') + + # prevent moving forward with empty contents + if not line: + continue + + # splitting on ';' because that is what the lvm call uses as + # '--separator' + output_items = [i.strip() for i in line.split(';')] + # map the output to the fields + report.append( + dict(zip(field_items, output_items)) + ) + + return report + + +def _splitname_parser(line): + """ + Parses the output from ``dmsetup splitname``, that should contain prefixes + (--nameprefixes) and set the separator to ";" + + Output for /dev/mapper/vg-lv will usually look like:: + + DM_VG_NAME='/dev/mapper/vg';DM_LV_NAME='lv';DM_LV_LAYER='' + + + The ``VG_NAME`` will usually not be what other callers need (e.g. just 'vg' + in the example), so this utility will split ``/dev/mapper/`` out, so that + the actual volume group name is kept + + :returns: dictionary with stripped prefixes + """ + parsed = {} + try: + parts = line[0].split(';') + except IndexError: + logger.exception('Unable to parse mapper device: %s', line) + return parsed + + for part in parts: + part = part.replace("'", '') + key, value = part.split('=') + if 'DM_VG_NAME' in key: + value = value.split('/dev/mapper/')[-1] + key = key.split('DM_')[-1] + parsed[key] = value + + return parsed + + +def sizing(device_size, parts=None, size=None): + """ + Calculate proper sizing to fully utilize the volume group in the most + efficient way possible. To prevent situations where LVM might accept + a percentage that is beyond the vg's capabilities, it will refuse with + an error when requesting a larger-than-possible parameter, in addition + to rounding down calculations. + + A dictionary with different sizing parameters is returned, to make it + easier for others to choose what they need in order to create logical + volumes:: + + >>> sizing(100, parts=2) + >>> {'parts': 2, 'percentages': 50, 'sizes': 50} + + """ + if parts is not None and size is not None: + raise ValueError( + "Cannot process sizing with both parts (%s) and size (%s)" % (parts, size) + ) + + if size and size > device_size: + raise SizeAllocationError(size, device_size) + + def get_percentage(parts): + return int(floor(100 / float(parts))) + + if parts is not None: + # Prevent parts being 0, falling back to 1 (100% usage) + parts = parts or 1 + percentages = get_percentage(parts) + + if size: + parts = int(device_size / size) or 1 + percentages = get_percentage(parts) + + sizes = device_size / parts if parts else int(floor(device_size)) + + return { + 'parts': parts, + 'percentages': percentages, + 'sizes': int(sizes/1024/1024/1024), + } + + +def parse_tags(lv_tags): + """ + Return a dictionary mapping of all the tags associated with + a Volume from the comma-separated tags coming from the LVM API + + Input look like:: + + "ceph.osd_fsid=aaa-fff-bbbb,ceph.osd_id=0" + + For the above example, the expected return value would be:: + + { + "ceph.osd_fsid": "aaa-fff-bbbb", + "ceph.osd_id": "0" + } + """ + if not lv_tags: + return {} + tag_mapping = {} + tags = lv_tags.split(',') + for tag_assignment in tags: + if not tag_assignment.startswith('ceph.'): + continue + key, value = tag_assignment.split('=', 1) + tag_mapping[key] = value + + return tag_mapping + + +def _vdo_parents(devices): + """ + It is possible we didn't get a logical volume, or a mapper path, but + a device like /dev/sda2, to resolve this, we must look at all the slaves of + every single device in /sys/block and if any of those devices is related to + VDO devices, then we can add the parent + """ + parent_devices = [] + for parent in os.listdir('/sys/block'): + for slave in os.listdir('/sys/block/%s/slaves' % parent): + if slave in devices: + parent_devices.append('/dev/%s' % parent) + parent_devices.append(parent) + return parent_devices + + +def _vdo_slaves(vdo_names): + """ + find all the slaves associated with each vdo name (from realpath) by going + into /sys/block/<realpath>/slaves + """ + devices = [] + for vdo_name in vdo_names: + mapper_path = '/dev/mapper/%s' % vdo_name + if not os.path.exists(mapper_path): + continue + # resolve the realpath and realname of the vdo mapper + vdo_realpath = os.path.realpath(mapper_path) + vdo_realname = vdo_realpath.split('/')[-1] + slaves_path = '/sys/block/%s/slaves' % vdo_realname + if not os.path.exists(slaves_path): + continue + devices.append(vdo_realpath) + devices.append(mapper_path) + devices.append(vdo_realname) + for slave in os.listdir(slaves_path): + devices.append('/dev/%s' % slave) + devices.append(slave) + return devices + + +def _is_vdo(path): + """ + A VDO device can be composed from many different devices, go through each + one of those devices and its slaves (if any) and correlate them back to + /dev/mapper and their realpaths, and then check if they appear as part of + /sys/kvdo/<name>/statistics + + From the realpath of a logical volume, determine if it is a VDO device or + not, by correlating it to the presence of the name in + /sys/kvdo/<name>/statistics and all the previously captured devices + """ + if not os.path.isdir('/sys/kvdo'): + return False + realpath = os.path.realpath(path) + realpath_name = realpath.split('/')[-1] + devices = [] + vdo_names = set() + # get all the vdo names + for dirname in os.listdir('/sys/kvdo/'): + if os.path.isdir('/sys/kvdo/%s/statistics' % dirname): + vdo_names.add(dirname) + + # find all the slaves associated with each vdo name (from realpath) by + # going into /sys/block/<realpath>/slaves + devices.extend(_vdo_slaves(vdo_names)) + + # Find all possible parents, looking into slaves that are related to VDO + devices.extend(_vdo_parents(devices)) + + return any([ + path in devices, + realpath in devices, + realpath_name in devices]) + + +def is_vdo(path): + """ + Detect if a path is backed by VDO, proxying the actual call to _is_vdo so + that we can prevent an exception breaking OSD creation. If an exception is + raised, it will get captured and logged to file, while returning + a ``False``. + """ + try: + if _is_vdo(path): + return '1' + return '0' + except Exception: + logger.exception('Unable to properly detect device as VDO: %s', path) + return '0' + + +def dmsetup_splitname(dev): + """ + Run ``dmsetup splitname`` and parse the results. + + .. warning:: This call does not ensure that the device is correct or that + it exists. ``dmsetup`` will happily take a non existing path and still + return a 0 exit status. + """ + command = [ + 'dmsetup', 'splitname', '--noheadings', + "--separator=';'", '--nameprefixes', dev + ] + out, err, rc = process.call(command) + return _splitname_parser(out) + + +def is_ceph_device(lv): + try: + lv.tags['ceph.osd_id'] + except (KeyError, AttributeError): + logger.warning('device is not part of ceph: %s', lv) + return False + + if lv.tags['ceph.osd_id'] == 'null': + return False + else: + return True + + +#################################### +# +# Code for LVM Physical Volumes +# +################################ + +PV_FIELDS = 'pv_name,pv_tags,pv_uuid,vg_name,lv_uuid' + +class PVolume(object): + """ + Represents a Physical Volume from LVM, with some top-level attributes like + ``pv_name`` and parsed tags as a dictionary of key/value pairs. + """ + + def __init__(self, **kw): + for k, v in kw.items(): + setattr(self, k, v) + self.pv_api = kw + self.name = kw['pv_name'] + self.tags = parse_tags(kw['pv_tags']) + + def __str__(self): + return '<%s>' % self.pv_api['pv_name'] + + def __repr__(self): + return self.__str__() + + def set_tags(self, tags): + """ + :param tags: A dictionary of tag names and values, like:: + + { + "ceph.osd_fsid": "aaa-fff-bbbb", + "ceph.osd_id": "0" + } + + At the end of all modifications, the tags are refreshed to reflect + LVM's most current view. + """ + for k, v in tags.items(): + self.set_tag(k, v) + # after setting all the tags, refresh them for the current object, use the + # pv_* identifiers to filter because those shouldn't change + pv_object = self.get_first_pv(filter={'pv_name': self.pv_name, + 'pv_uuid': self.pv_uuid}) + self.tags = pv_object.tags + + def set_tag(self, key, value): + """ + Set the key/value pair as an LVM tag. Does not "refresh" the values of + the current object for its tags. Meant to be a "fire and forget" type + of modification. + + **warning**: Altering tags on a PV has to be done ensuring that the + device is actually the one intended. ``pv_name`` is *not* a persistent + value, only ``pv_uuid`` is. Using ``pv_uuid`` is the best way to make + sure the device getting changed is the one needed. + """ + # remove it first if it exists + if self.tags.get(key): + current_value = self.tags[key] + tag = "%s=%s" % (key, current_value) + process.call(['pvchange', '--deltag', tag, self.pv_name]) + + process.call( + [ + 'pvchange', + '--addtag', '%s=%s' % (key, value), self.pv_name + ] + ) + + +def create_pv(device): + """ + Create a physical volume from a device, useful when devices need to be later mapped + to journals. + """ + process.run([ + 'pvcreate', + '-v', # verbose + '-f', # force it + '--yes', # answer yes to any prompts + device + ]) + + +def remove_pv(pv_name): + """ + Removes a physical volume using a double `-f` to prevent prompts and fully + remove anything related to LVM. This is tremendously destructive, but so is all other actions + when zapping a device. + + In the case where multiple PVs are found, it will ignore that fact and + continue with the removal, specifically in the case of messages like:: + + WARNING: PV $UUID /dev/DEV-1 was already found on /dev/DEV-2 + + These situations can be avoided with custom filtering rules, which this API + cannot handle while accommodating custom user filters. + """ + fail_msg = "Unable to remove vg %s" % pv_name + process.run( + [ + 'pvremove', + '-v', # verbose + '-f', # force it + '-f', # force it + pv_name + ], + fail_msg=fail_msg, + ) + + +def get_pvs(fields=PV_FIELDS, filters='', tags=None): + """ + Return a list of PVs that are available on the system and match the + filters and tags passed. Argument filters takes a dictionary containing + arguments required by -S option of LVM. Passing a list of LVM tags can be + quite tricky to pass as a dictionary within dictionary, therefore pass + dictionary of tags via tags argument and tricky part will be taken care of + by the helper methods. + + :param fields: string containing list of fields to be displayed by the + pvs command + :param sep: string containing separator to be used between two fields + :param filters: dictionary containing LVM filters + :param tags: dictionary containng LVM tags + :returns: list of class PVolume object representing pvs on the system + """ + filters = make_filters_lvmcmd_ready(filters, tags) + args = ['pvs', '--no-heading', '--readonly', '--separator=";"', '-S', + filters, '-o', fields] + + stdout, stderr, returncode = process.call(args, verbose_on_failure=False) + pvs_report = _output_parser(stdout, fields) + return [PVolume(**pv_report) for pv_report in pvs_report] + + +def get_first_pv(fields=PV_FIELDS, filters=None, tags=None): + """ + Wrapper of get_pv meant to be a convenience method to avoid the phrase:: + pvs = get_pvs() + if len(pvs) >= 1: + pv = pvs[0] + """ + pvs = get_pvs(fields=fields, filters=filters, tags=tags) + return pvs[0] if len(pvs) > 0 else [] + + +################################ +# +# Code for LVM Volume Groups +# +############################# + +VG_FIELDS = 'vg_name,pv_count,lv_count,vg_attr,vg_extent_count,vg_free_count,vg_extent_size' +VG_CMD_OPTIONS = ['--noheadings', '--readonly', '--units=b', '--nosuffix', '--separator=";"'] + + +class VolumeGroup(object): + """ + Represents an LVM group, with some top-level attributes like ``vg_name`` + """ + + def __init__(self, **kw): + for k, v in kw.items(): + setattr(self, k, v) + self.name = kw['vg_name'] + if not self.name: + raise ValueError('VolumeGroup must have a non-empty name') + self.tags = parse_tags(kw.get('vg_tags', '')) + + def __str__(self): + return '<%s>' % self.name + + def __repr__(self): + return self.__str__() + + @property + def free(self): + """ + Return free space in VG in bytes + """ + return int(self.vg_extent_size) * int(self.vg_free_count) + + @property + def free_percent(self): + """ + Return free space in VG in bytes + """ + return int(self.vg_free_count) / int(self.vg_extent_count) + + @property + def size(self): + """ + Returns VG size in bytes + """ + return int(self.vg_extent_size) * int(self.vg_extent_count) + + def sizing(self, parts=None, size=None): + """ + Calculate proper sizing to fully utilize the volume group in the most + efficient way possible. To prevent situations where LVM might accept + a percentage that is beyond the vg's capabilities, it will refuse with + an error when requesting a larger-than-possible parameter, in addition + to rounding down calculations. + + A dictionary with different sizing parameters is returned, to make it + easier for others to choose what they need in order to create logical + volumes:: + + >>> data_vg.free + 1024 + >>> data_vg.sizing(parts=4) + {'parts': 4, 'sizes': 256, 'percentages': 25} + >>> data_vg.sizing(size=512) + {'parts': 2, 'sizes': 512, 'percentages': 50} + + + :param parts: Number of parts to create LVs from + :param size: Size in gigabytes to divide the VG into + + :raises SizeAllocationError: When requested size cannot be allocated with + :raises ValueError: If both ``parts`` and ``size`` are given + """ + if parts is not None and size is not None: + raise ValueError( + "Cannot process sizing with both parts (%s) and size (%s)" % (parts, size) + ) + + # if size is given we need to map that to extents so that we avoid + # issues when trying to get this right with a size in gigabytes find + # the percentage first, cheating, because these values are thrown out + vg_free_count = util.str_to_int(self.vg_free_count) + + if size: + size = size * 1024 * 1024 * 1024 + extents = int(size / int(self.vg_extent_size)) + disk_sizing = sizing(self.free, size=size, parts=parts) + else: + if parts is not None: + # Prevent parts being 0, falling back to 1 (100% usage) + parts = parts or 1 + size = int(self.free / parts) + extents = size * vg_free_count / self.free + disk_sizing = sizing(self.free, parts=parts) + + extent_sizing = sizing(vg_free_count, size=extents) + + disk_sizing['extents'] = int(extents) + disk_sizing['percentages'] = extent_sizing['percentages'] + return disk_sizing + + def bytes_to_extents(self, size): + ''' + Return a how many free extents we can fit into a size in bytes. This has + some uncertainty involved. If size/extent_size is within 1% of the + actual free extents we will return the extent count, otherwise we'll + throw an error. + This accomodates for the size calculation in batch. We need to report + the OSD layout but have not yet created any LVM structures. We use the + disk size in batch if no VG is present and that will overshoot the + actual free_extent count due to LVM overhead. + + ''' + b_to_ext = int(size / int(self.vg_extent_size)) + if b_to_ext < int(self.vg_free_count): + # return bytes in extents if there is more space + return b_to_ext + elif b_to_ext / int(self.vg_free_count) - 1 < 0.01: + # return vg_fre_count if its less then 1% off + logger.info( + 'bytes_to_extents results in {} but only {} ' + 'are available, adjusting the latter'.format(b_to_ext, + self.vg_free_count)) + return int(self.vg_free_count) + # else raise an exception + raise RuntimeError('Can\'t convert {} to free extents, only {} ({} ' + 'bytes) are free'.format(size, self.vg_free_count, + self.free)) + + def slots_to_extents(self, slots): + ''' + Return how many extents fit the VG slot times + ''' + return int(int(self.vg_extent_count) / slots) + + +def create_vg(devices, name=None, name_prefix=None): + """ + Create a Volume Group. Command looks like:: + + vgcreate --force --yes group_name device + + Once created the volume group is returned as a ``VolumeGroup`` object + + :param devices: A list of devices to create a VG. Optionally, a single + device (as a string) can be used. + :param name: Optionally set the name of the VG, defaults to 'ceph-{uuid}' + :param name_prefix: Optionally prefix the name of the VG, which will get combined + with a UUID string + """ + if isinstance(devices, set): + devices = list(devices) + if not isinstance(devices, list): + devices = [devices] + if name_prefix: + name = "%s-%s" % (name_prefix, str(uuid.uuid4())) + elif name is None: + name = "ceph-%s" % str(uuid.uuid4()) + process.run([ + 'vgcreate', + '--force', + '--yes', + name] + devices + ) + + return get_first_vg(filters={'vg_name': name}) + + +def extend_vg(vg, devices): + """ + Extend a Volume Group. Command looks like:: + + vgextend --force --yes group_name [device, ...] + + Once created the volume group is extended and returned as a ``VolumeGroup`` object + + :param vg: A VolumeGroup object + :param devices: A list of devices to extend the VG. Optionally, a single + device (as a string) can be used. + """ + if not isinstance(devices, list): + devices = [devices] + process.run([ + 'vgextend', + '--force', + '--yes', + vg.name] + devices + ) + + return get_first_vg(filters={'vg_name': vg.name}) + + +def reduce_vg(vg, devices): + """ + Reduce a Volume Group. Command looks like:: + + vgreduce --force --yes group_name [device, ...] + + :param vg: A VolumeGroup object + :param devices: A list of devices to remove from the VG. Optionally, a + single device (as a string) can be used. + """ + if not isinstance(devices, list): + devices = [devices] + process.run([ + 'vgreduce', + '--force', + '--yes', + vg.name] + devices + ) + + return get_first_vg(filter={'vg_name': vg.name}) + + +def remove_vg(vg_name): + """ + Removes a volume group. + """ + if not vg_name: + logger.warning('Skipping removal of invalid VG name: "%s"', vg_name) + return + fail_msg = "Unable to remove vg %s" % vg_name + process.run( + [ + 'vgremove', + '-v', # verbose + '-f', # force it + vg_name + ], + fail_msg=fail_msg, + ) + + +def get_vgs(fields=VG_FIELDS, filters='', tags=None): + """ + Return a list of VGs that are available on the system and match the + filters and tags passed. Argument filters takes a dictionary containing + arguments required by -S option of LVM. Passing a list of LVM tags can be + quite tricky to pass as a dictionary within dictionary, therefore pass + dictionary of tags via tags argument and tricky part will be taken care of + by the helper methods. + + :param fields: string containing list of fields to be displayed by the + vgs command + :param sep: string containing separator to be used between two fields + :param filters: dictionary containing LVM filters + :param tags: dictionary containng LVM tags + :returns: list of class VolumeGroup object representing vgs on the system + """ + filters = make_filters_lvmcmd_ready(filters, tags) + args = ['vgs'] + VG_CMD_OPTIONS + ['-S', filters, '-o', fields] + + stdout, stderr, returncode = process.call(args, verbose_on_failure=False) + vgs_report =_output_parser(stdout, fields) + return [VolumeGroup(**vg_report) for vg_report in vgs_report] + + +def get_first_vg(fields=VG_FIELDS, filters=None, tags=None): + """ + Wrapper of get_vg meant to be a convenience method to avoid the phrase:: + vgs = get_vgs() + if len(vgs) >= 1: + vg = vgs[0] + """ + vgs = get_vgs(fields=fields, filters=filters, tags=tags) + return vgs[0] if len(vgs) > 0 else [] + + +def get_device_vgs(device, name_prefix=''): + stdout, stderr, returncode = process.call( + ['pvs'] + VG_CMD_OPTIONS + ['-o', VG_FIELDS, device], + verbose_on_failure=False + ) + vgs = _output_parser(stdout, VG_FIELDS) + return [VolumeGroup(**vg) for vg in vgs if vg['vg_name'] and vg['vg_name'].startswith(name_prefix)] + + +################################# +# +# Code for LVM Logical Volumes +# +############################### + +LV_FIELDS = 'lv_tags,lv_path,lv_name,vg_name,lv_uuid,lv_size' +LV_CMD_OPTIONS = ['--noheadings', '--readonly', '--separator=";"', '-a', + '--units=b', '--nosuffix'] + + +class Volume(object): + """ + Represents a Logical Volume from LVM, with some top-level attributes like + ``lv_name`` and parsed tags as a dictionary of key/value pairs. + """ + + def __init__(self, **kw): + for k, v in kw.items(): + setattr(self, k, v) + self.lv_api = kw + self.name = kw['lv_name'] + if not self.name: + raise ValueError('Volume must have a non-empty name') + self.tags = parse_tags(kw['lv_tags']) + self.encrypted = self.tags.get('ceph.encrypted', '0') == '1' + self.used_by_ceph = 'ceph.osd_id' in self.tags + + def __str__(self): + return '<%s>' % self.lv_api['lv_path'] + + def __repr__(self): + return self.__str__() + + def as_dict(self): + obj = {} + obj.update(self.lv_api) + obj['tags'] = self.tags + obj['name'] = self.name + obj['type'] = self.tags['ceph.type'] + obj['path'] = self.lv_path + return obj + + def report(self): + if not self.used_by_ceph: + return { + 'name': self.lv_name, + 'comment': 'not used by ceph' + } + else: + type_ = self.tags['ceph.type'] + report = { + 'name': self.lv_name, + 'osd_id': self.tags['ceph.osd_id'], + 'cluster_name': self.tags['ceph.cluster_name'], + 'type': type_, + 'osd_fsid': self.tags['ceph.osd_fsid'], + 'cluster_fsid': self.tags['ceph.cluster_fsid'], + 'osdspec_affinity': self.tags.get('ceph.osdspec_affinity', ''), + } + type_uuid = '{}_uuid'.format(type_) + report[type_uuid] = self.tags['ceph.{}'.format(type_uuid)] + return report + + def _format_tag_args(self, op, tags): + tag_args = ['{}={}'.format(k, v) for k, v in tags.items()] + # weird but efficient way of ziping two lists and getting a flat list + return list(sum(zip(repeat(op), tag_args), ())) + + def clear_tags(self, keys=None): + """ + Removes all or passed tags from the Logical Volume. + """ + if not keys: + keys = self.tags.keys() + + del_tags = {k: self.tags[k] for k in keys if k in self.tags} + if not del_tags: + # nothing to clear + return + del_tag_args = self._format_tag_args('--deltag', del_tags) + # --deltag returns successful even if the to be deleted tag is not set + process.call(['lvchange'] + del_tag_args + [self.lv_path]) + for k in del_tags.keys(): + del self.tags[k] + + + def set_tags(self, tags): + """ + :param tags: A dictionary of tag names and values, like:: + + { + "ceph.osd_fsid": "aaa-fff-bbbb", + "ceph.osd_id": "0" + } + + At the end of all modifications, the tags are refreshed to reflect + LVM's most current view. + """ + self.clear_tags(tags.keys()) + add_tag_args = self._format_tag_args('--addtag', tags) + process.call(['lvchange'] + add_tag_args + [self.lv_path]) + for k, v in tags.items(): + self.tags[k] = v + + + def clear_tag(self, key): + if self.tags.get(key): + current_value = self.tags[key] + tag = "%s=%s" % (key, current_value) + process.call(['lvchange', '--deltag', tag, self.lv_path]) + del self.tags[key] + + + def set_tag(self, key, value): + """ + Set the key/value pair as an LVM tag. + """ + # remove it first if it exists + self.clear_tag(key) + + process.call( + [ + 'lvchange', + '--addtag', '%s=%s' % (key, value), self.lv_path + ] + ) + self.tags[key] = value + + def deactivate(self): + """ + Deactivate the LV by calling lvchange -an + """ + process.call(['lvchange', '-an', self.lv_path]) + + +def create_lv(name_prefix, + uuid, + vg=None, + device=None, + slots=None, + extents=None, + size=None, + tags=None): + """ + Create a Logical Volume in a Volume Group. Command looks like:: + + lvcreate -L 50G -n gfslv vg0 + + ``name_prefix`` is required. If ``size`` is provided its expected to be a + byte count. Tags are an optional dictionary and is expected to + conform to the convention of prefixing them with "ceph." like:: + + {"ceph.block_device": "/dev/ceph/osd-1"} + + :param name_prefix: name prefix for the LV, typically somehting like ceph-osd-block + :param uuid: UUID to ensure uniqueness; is combined with name_prefix to + form the LV name + :param vg: optional, pass an existing VG to create LV + :param device: optional, device to use. Either device of vg must be passed + :param slots: optional, number of slots to divide vg up, LV will occupy one + one slot if enough space is available + :param extends: optional, how many lvm extends to use, supersedes slots + :param size: optional, target LV size in bytes, supersedes extents, + resulting LV might be smaller depending on extent + size of the underlying VG + :param tags: optional, a dict of lvm tags to set on the LV + """ + name = '{}-{}'.format(name_prefix, uuid) + if not vg: + if not device: + raise RuntimeError("Must either specify vg or device, none given") + # check if a vgs starting with ceph already exists + vgs = get_device_vgs(device, 'ceph') + if vgs: + vg = vgs[0] + else: + # create on if not + vg = create_vg(device, name_prefix='ceph') + assert(vg) + + if size: + extents = vg.bytes_to_extents(size) + logger.debug('size was passed: {} -> {}'.format(size, extents)) + elif slots and not extents: + extents = vg.slots_to_extents(slots) + logger.debug('slots was passed: {} -> {}'.format(slots, extents)) + + if extents: + command = [ + 'lvcreate', + '--yes', + '-l', + '{}'.format(extents), + '-n', name, vg.vg_name + ] + # create the lv with all the space available, this is needed because the + # system call is different for LVM + else: + command = [ + 'lvcreate', + '--yes', + '-l', + '100%FREE', + '-n', name, vg.vg_name + ] + process.run(command) + + lv = get_first_lv(filters={'lv_name': name, 'vg_name': vg.vg_name}) + + if tags is None: + tags = { + "ceph.osd_id": "null", + "ceph.type": "null", + "ceph.cluster_fsid": "null", + "ceph.osd_fsid": "null", + } + # when creating a distinct type, the caller doesn't know what the path will + # be so this function will set it after creation using the mapping + # XXX add CEPH_VOLUME_LVM_DEBUG to enable -vvvv on lv operations + type_path_tag = { + 'journal': 'ceph.journal_device', + 'data': 'ceph.data_device', + 'block': 'ceph.block_device', + 'wal': 'ceph.wal_device', + 'db': 'ceph.db_device', + 'lockbox': 'ceph.lockbox_device', # XXX might not ever need this lockbox sorcery + } + path_tag = type_path_tag.get(tags.get('ceph.type')) + if path_tag: + tags.update({path_tag: lv.lv_path}) + + lv.set_tags(tags) + + return lv + + +def create_lvs(volume_group, parts=None, size=None, name_prefix='ceph-lv'): + """ + Create multiple Logical Volumes from a Volume Group by calculating the + proper extents from ``parts`` or ``size``. A custom prefix can be used + (defaults to ``ceph-lv``), these names are always suffixed with a uuid. + + LV creation in ceph-volume will require tags, this is expected to be + pre-computed by callers who know Ceph metadata like OSD IDs and FSIDs. It + will probably not be the case when mass-creating LVs, so common/default + tags will be set to ``"null"``. + + .. note:: LVs that are not in use can be detected by querying LVM for tags that are + set to ``"null"``. + + :param volume_group: The volume group (vg) to use for LV creation + :type group: ``VolumeGroup()`` object + :param parts: Number of LVs to create *instead of* ``size``. + :type parts: int + :param size: Size (in gigabytes) of LVs to create, e.g. "as many 10gb LVs as possible" + :type size: int + :param extents: The number of LVM extents to use to create the LV. Useful if looking to have + accurate LV sizes (LVM rounds sizes otherwise) + """ + if parts is None and size is None: + # fallback to just one part (using 100% of the vg) + parts = 1 + lvs = [] + tags = { + "ceph.osd_id": "null", + "ceph.type": "null", + "ceph.cluster_fsid": "null", + "ceph.osd_fsid": "null", + } + sizing = volume_group.sizing(parts=parts, size=size) + for part in range(0, sizing['parts']): + size = sizing['sizes'] + extents = sizing['extents'] + lvs.append( + create_lv(name_prefix, uuid.uuid4(), vg=volume_group, extents=extents, tags=tags) + ) + return lvs + + +def remove_lv(lv): + """ + Removes a logical volume given it's absolute path. + + Will return True if the lv is successfully removed or + raises a RuntimeError if the removal fails. + + :param lv: A ``Volume`` object or the path for an LV + """ + if isinstance(lv, Volume): + path = lv.lv_path + else: + path = lv + + stdout, stderr, returncode = process.call( + [ + 'lvremove', + '-v', # verbose + '-f', # force it + path + ], + show_command=True, + terminal_verbose=True, + ) + if returncode != 0: + raise RuntimeError("Unable to remove %s" % path) + return True + + +def get_lvs(fields=LV_FIELDS, filters='', tags=None): + """ + Return a list of LVs that are available on the system and match the + filters and tags passed. Argument filters takes a dictionary containing + arguments required by -S option of LVM. Passing a list of LVM tags can be + quite tricky to pass as a dictionary within dictionary, therefore pass + dictionary of tags via tags argument and tricky part will be taken care of + by the helper methods. + + :param fields: string containing list of fields to be displayed by the + lvs command + :param sep: string containing separator to be used between two fields + :param filters: dictionary containing LVM filters + :param tags: dictionary containng LVM tags + :returns: list of class Volume object representing LVs on the system + """ + filters = make_filters_lvmcmd_ready(filters, tags) + args = ['lvs'] + LV_CMD_OPTIONS + ['-S', filters, '-o', fields] + + stdout, stderr, returncode = process.call(args, verbose_on_failure=False) + lvs_report = _output_parser(stdout, fields) + return [Volume(**lv_report) for lv_report in lvs_report] + + +def get_first_lv(fields=LV_FIELDS, filters=None, tags=None): + """ + Wrapper of get_lv meant to be a convenience method to avoid the phrase:: + lvs = get_lvs() + if len(lvs) >= 1: + lv = lvs[0] + """ + lvs = get_lvs(fields=fields, filters=filters, tags=tags) + return lvs[0] if len(lvs) > 0 else [] + + +def get_lv_by_name(name): + stdout, stderr, returncode = process.call( + ['lvs', '--noheadings', '-o', LV_FIELDS, '-S', + 'lv_name={}'.format(name)], + verbose_on_failure=False + ) + lvs = _output_parser(stdout, LV_FIELDS) + return [Volume(**lv) for lv in lvs] + + +def get_lvs_by_tag(lv_tag): + stdout, stderr, returncode = process.call( + ['lvs', '--noheadings', '--separator=";"', '-a', '-o', LV_FIELDS, '-S', + 'lv_tags={{{}}}'.format(lv_tag)], + verbose_on_failure=False + ) + lvs = _output_parser(stdout, LV_FIELDS) + return [Volume(**lv) for lv in lvs] + + +def get_device_lvs(device, name_prefix=''): + stdout, stderr, returncode = process.call( + ['pvs'] + LV_CMD_OPTIONS + ['-o', LV_FIELDS, device], + verbose_on_failure=False + ) + lvs = _output_parser(stdout, LV_FIELDS) + return [Volume(**lv) for lv in lvs if lv['lv_name'] and + lv['lv_name'].startswith(name_prefix)] |