WHY IS LVM THE WORST THING ON THIS PLANET

This commit is contained in:
brent s 2019-11-06 12:48:18 -05:00
parent f424938913
commit 5f8caf48d6
9 changed files with 241 additions and 38 deletions

26
aif.xsd
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@ -501,22 +501,24 @@
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="tags" minOccurs="0" maxOccurs="1">
<xs:complexType>
<xs:sequence>
<xs:element name="tag" type="aif:t_nonempty"
minOccurs="1" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<!-- PV creation doesn't really support tags, it seems,
in libblockdev. So we'll simplify and just skip them. -->
<!-- <xs:element name="tags" minOccurs="0" maxOccurs="1">-->
<!-- <xs:complexType>-->
<!-- <xs:sequence>-->
<!-- <xs:element name="tag" type="aif:t_nonempty"-->
<!-- minOccurs="1" maxOccurs="unbounded"/>-->
<!-- </xs:sequence>-->
<!-- </xs:complexType>-->
<!-- </xs:element>-->
</xs:all>
<xs:attribute name="id" type="xs:ID" use="required"/>
<xs:attribute name="name" type="aif:t_nonempty" use="required"/>
</xs:complexType>
<xs:unique name="uniq_vg_tags">
<xs:selector xpath="aif:tags"/>
<xs:field xpath="tag"/>
</xs:unique>
<!-- <xs:unique name="uniq_vg_tags">-->
<!-- <xs:selector xpath="aif:tags"/>-->
<!-- <xs:field xpath="tag"/>-->
<!-- </xs:unique>-->
</xs:element>
</xs:sequence>
</xs:complexType>

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@ -2,7 +2,7 @@ try:
from . import constants
except ImportError:
from . import constants_fallback as constants

from . import constants_fallback
from . import utils
from . import disk
from . import system

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@ -1,3 +1,5 @@
import uuid
##
from . import _common
import aif.disk.block as block
import aif.disk.luks as luks
@ -10,21 +12,181 @@ _BlockDev = _common.BlockDev
class PV(object):
def __init__(self, pv_xml, partobj):
self.xml = pv_xml
self.id = self.xml.attrib('id')
self.source = self.xml.attrib('source')
self.device = partobj
if not isinstance(self.device, (block.Disk,
block.Partition,
luks.LUKS,
mdadm.Array)):
raise ValueError(('partobj must be of type '
'aif.disk.block.Disk, '
'aif.disk.block.Partition, '
'aif.disk.luks.LUKS, or'
'aif.disk.mdadm.Array'))
_common.addBDPlugin('lvm')
self.devpath = None
pass
self.devpath = self.device.devpath
self.is_pooled = False
self.meta = None
self._parseMeta()

def _parseMeta(self):
# Note, the "UUID" for LVM is *not* a true UUID (RFC4122) so we don't convert it.
# https://unix.stackexchange.com/questions/173722/what-is-the-uuid-format-used-by-lvm
# TODO: parity with lvm_fallback.PV._parseMeta
# key names currently (probably) don't match and need to confirm the information's all present
meta = {}
try:
_meta = _BlockDev.lvm.pvinfo(self.devpath)
except _BlockDev.LVMError:
self.meta = None
self.is_pooled = False
return()
for k in dir(_meta):
if k.startswith('_'):
continue
elif k in ('copy',):
continue
v = getattr(_meta, k)
meta[k] = v
self.meta = meta
self.is_pooled = True
return()

def prepare(self):
try:
if not self.meta:
self._parseMeta()
if self.meta:
vg = self.meta['vg_name']
# LVM is SO. DUMB.
# If you're using LVM, seriously - just switch your model to mdadm. It lets you do things like
# remove disks live without restructuring the entire thing.
# That said, because the config references partitions/disks/arrays/etc. created *in the same config*,
# and it's all dependent on block devices defined in the thing, we can be reckless here.
# I'd like to take the time now to remind you to NOT RUN AIF-NG ON A "LIVE" MACHINE.
# At least until I can maybe find a better way to determine which LVs to reduce on multi-LV VGs
# so I can *then* use lvresize in a balanced manner, vgreduce, and pvmove/pvremove and not kill
# everything.
# TODO.
for lv in _BlockDev.lvm.lvs():
if lv.vg_name == vg:
_BlockDev.lvm.lvremove(vg, lv.lv_name)
_BlockDev.lvm.vgreduce(vg)
_BlockDev.lvm.vgremove(vg) # This *shouldn't* fail. In theory. But LVM is lel.
_BlockDev.lvm.pvremove(self.devpath)
# Or if I can get this working properly. Shame it isn't automagic.
# Seems to kill the LV by dropping a PV under it. Makes sense, but STILL. LVM IS SO DUMB.
# _BlockDev.lvm.vgdeactivate(vg)
# _BlockDev.lvm.pvremove(self.devpath)
# _BlockDev.lvm.vgreduce(vg)
# _BlockDev.lvm.vgactivate(vg)
##
self.meta = None
self.is_pooled = False
except _BlockDev.LVMError:
self.meta = None
self.is_pooled = False
u = uuid.uuid4()
opts = [_BlockDev.ExtraArg.new('--reportformat', 'json')]
# FUCK. LVM. You can't *specify* a UUID.
# u = uuid.uuid4()
# opts.append(_BlockDev.ExtraArg.new('--uuid', str(u)))
_BlockDev.lvm.pvcreate(self.devpath,
0,
0,
opts)
self._parseMeta()
return()


class VG(object):
def __init__(self, vg_xml, lv_objs):
def __init__(self, vg_xml):
self.xml = vg_xml
self.id = self.xml.attrib('id')
self.name = self.xml.attrib('name')
self.lvs = []
self.pvs = []
self.tags = []
for te in self.xml.findall('tags/tag'):
self.tags.append(te.text)
_common.addBDPlugin('lvm')
self.devpath = None
self.devpath = self.name
self.info = None

def addPV(self, pvobj):
if not isinstance(pvobj, PV):
raise ValueError('pvobj must be of type aif.disk.lvm.PV')
pvobj.prepare()
self.pvs.append(pvobj)
return()

def create(self):
if not self.pvs:
raise RuntimeError('Cannot create a VG with no PVs')
opts = [_BlockDev.ExtraArg.new('--reportformat', 'json')]
# FUCK. LVM. You can't *specify* a UUID.
# u = uuid.uuid4()
# opts.append(_BlockDev.ExtraArg.new('--uuid', str(u)))
for t in self.tags:
opts.append(_BlockDev.ExtraArg.new('--addtag', t))
_BlockDev.lvm.vgcreate(self.name,
[p.devpath for p in self.pvs],
0,
opts)
for p in self.pvs:
p._parseMeta()
self.updateInfo()
return()

def createLV(self, lv_xml = None):
# If lv_xml is None, we loop through our own XML.
if lv_xml:
lv = LV(lv_xml, self)
lv.create()
self.lvs.append(lv)
else:
for le in self.xml.findall('logicalVolumes/lv'):
pass
self.updateInfo()
return()

def start(self):
_BlockDev.lvm.vgactivate(self.name)
self.updateInfo()
return()

def stop(self):
_BlockDev.lvm.vgdeactivate(self.name)
self.updateInfo()
return()

def updateInfo(self):
_info = _BlockDev.lvm.vginfo(self.name)
# TODO: parity with lvm_fallback.VG.updateInfo
# key names currently (probably) don't match and need to confirm the information's all present
info = {}
for k in dir(_info):
if k.startswith('_'):
continue
elif k in ('copy',):
continue
v = getattr(_info, k)
info[k] = v
self.info = info
return()


class LV(object):
def __init__(self, lv_xml, pv_objs):
def __init__(self, lv_xml, vgobj):
self.xml = lv_xml
self.id = self.xml.attrib('id')
self.name = self.xml.attrib('name')
self.size = self.xml.attrib('size') # Convert to bytes. Can get max from _BlockDev.lvm.vginfo(<VG>).free
self.vg = vg_obj
if not isinstance(self.vg, VG):
raise ValueError('vg_obj must be of type aif.disk.lvm.VG')
_common.addBDPlugin('lvm')

self.devpath = None
pass

View File

@ -6,17 +6,53 @@ import aif.disk.mdadm_fallback as mdadm


class PV(object):
def __init__(self, partobj):
def __init__(self, pv_xml, partobj):
self.xml = pv_xml
self.id = self.xml.attrib('id')
self.source = self.xml.attrib('source')
self.device = partobj
if not isinstance(self.device, (block.Disk,
block.Partition,
luks.LUKS,
mdadm.Array)):
raise ValueError(('partobj must be of type '
'aif.disk.block.Disk, '
'aif.disk.block.Partition, '
'aif.disk.luks.LUKS, or'
'aif.disk.mdadm.Array'))
# TODO
self.devpath = self.device.devpath
pass


class LV(object):
def __init__(self, lv_xml, pv_objs, vg_obj):
self.xml = lv_xml
self.id = self.xml.attrib('id')
self.name = self.xml.attrib('name')
self.size = self.xml.attrib('size') # Convert to bytes. Can get max from _BlockDev.lvm.vginfo(<VG>).free
self.pvs = pv_objs
self.vg = vg_obj
for p in self.pvs:
if not isinstance(p, PV):
raise ValueError('pv_objs must be a list-like containing aif.disk.lvm.PV items')
if not isinstance(self.vg, VG):
raise ValueError('vg_obj must be of type aif.disk.lvm.VG')
# TODO
self.devpath = None
pass


class VG(object):
def __init__(self, vg_xml, lv_objs):
self.xml = vg_xml
self.id = self.xml.attrib('id')
self.name = self.xml.attrib('name')
self.lvs = lv_objs
for l in self.lvs:
if not isinstance(l, LV):
raise ValueError('lv_objs must be a list-like containing aif.disk.lvm.LV items')
# TODO
self.devpath = None
pass


class LV(object):
def __init__(self, lv_xml, pv_objs):
pass

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@ -17,11 +17,11 @@ class Member(object):
def __init__(self, member_xml, partobj):
self.xml = member_xml
self.device = partobj
if not isinstance(self.device, (block.Partition,
block.Disk,
if not isinstance(self.device, (block.Disk,
block.Partition,
Array,
lvm.LV,
luks.LUKS)):
luks.LUKS,
lvm.LV)):
raise ValueError(('partobj must be of type '
'aif.disk.block.Disk, '
'aif.disk.block.Partition, '
@ -67,6 +67,7 @@ class Member(object):
except _BlockDev.MDRaidError:
pass
_BlockDev.md.destroy(self.devpath)
self._parseDeviceBlock()
return()



View File

@ -123,6 +123,7 @@ class Member(object):
# TODO: logging
subprocess.run(['mdadm', '--misc', '--zero-superblock', self.devpath])
self.is_superblocked = False
self._parseDeviceBlock()
return()

class Array(object):

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@ -12,7 +12,7 @@ import sys
import tempfile
import venv
##
import aif.constants
import aif.constants_fallback

class EnvBuilder(object):
def __init__(self):
@ -35,7 +35,7 @@ class EnvBuilder(object):
# This is SO. DUMB. WHY DO I HAVE TO CALL PIP FROM A SHELL. IT'S WRITTEN IN PYTHON.
# https://pip.pypa.io/en/stable/user_guide/#using-pip-from-your-program
# TODO: logging
for m in aif.constants.external_deps:
for m in aif.constants_fallback.EXTERNAL_DEPS:
pip_cmd = [os.path.join(self.vdir,
'bin',
'python3'),

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@ -57,15 +57,16 @@
</luks>
<lvm>
<volumeGroup id="vg1" name="group1">
<tags>
<tag>data</tag>
<tag>misc</tag>
</tags>
<physicalVolumes>
<pv id="pv1" source="lvm_member1"/>
</physicalVolumes>
<logicalVolumes>
<lv id="lv1" name="logical1" size="100%"/>
<!-- Default is to add all available PVs in PhysicalVolumes... -->
<lv id="lv1" name="logical1" size="80%"/>
<!-- But you can also explicitly designate them. -->
<lv id="lv2" name="logical1" size="20%">
<pvMember source="pv1"/>
</lv>
</logicalVolumes>
</volumeGroup>
</lvm>

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@ -1,12 +1,12 @@
import setuptools
import aif.constants as PROJ_CONST
import aif.constants_fallback as PROJ_CONST

with open('README', 'r') as fh:
long_description = fh.read()

setuptools.setup(
name = 'aif',
version = PROJ_CONST.version,
version = PROJ_CONST.VERSION,
author = 'Brent S.',
author_email = 'bts@square-r00t.net',
description = 'Arch Installation Framework (Next Generation)',
@ -32,5 +32,5 @@ setuptools.setup(
project_urls = {'Documentation': 'https://aif-ng.io/',
'Source': 'https://git.square-r00t.net/AIF-NG/',
'Tracker': 'https://bugs.square-r00t.net/index.php?project=9'},
install_requires = PROJ_CONST.external_deps
install_requires = PROJ_CONST.EXTERNAL_DEPS
)