storage/devicelibs/mdraid.py

#
# mdraid.py
# mdraid functions
#
# Copyright (C) 2009  Red Hat, Inc.  All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# 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/>.
#
# Author(s): Dave Lehman <dlehman@redhat.com>
#

import os

import iutil
from ..errors import *

import gettext
_ = lambda x: gettext.ldgettext("anaconda", x)

import logging
log = logging.getLogger("storage")

# raidlevels constants
RAID10 = 10
RAID6 = 6
RAID5 = 5
RAID4 = 4
RAID1 = 1
RAID0 = 0

def getRaidLevels():
    mdstat_descriptors = {
        RAID10: ("[RAID10]", "[raid10]"),
        RAID6: ("[RAID6]", "[raid6]"),
        RAID5: ("[RAID5]", "[raid5]"),
        RAID4: ("[RAID4]", "[raid4]"),
        RAID1: ("[RAID1]", "[raid1]"),
        RAID0: ("[RAID0]", "[raid0]"),
    }
    avail = []
    try:
        f = open("/proc/mdstat", "r")
    except IOError:
        pass
    else:
        for l in f.readlines():
            if not l.startswith("Personalities"):
                continue

            lst = l.split()

            for level in mdstat_descriptors:
                for d in mdstat_descriptors[level]:
                    if d in lst:
                        avail.append(level)
                        break

        f.close()

    avail.sort()
    return avail

raid_levels = getRaidLevels()

def raidLevel(descriptor):
    for level in raid_levels:
        if isRaid(level, descriptor):
            return level
    else:
        raise ValueError, "invalid raid level descriptor %s" % descriptor

def isRaid(raid, raidlevel):
    """Return whether raidlevel is a valid descriptor of raid"""
    raid_descriptors = {RAID10: ("RAID10", "raid10", "10", 10),
                        RAID6: ("RAID6", "raid6", "6", 6),
                        RAID5: ("RAID5", "raid5", "5", 5),
                        RAID4: ("RAID4", "raid4", "4", 4),
                        RAID1: ("mirror", "RAID1", "raid1", "1", 1),
                        RAID0: ("stripe", "RAID0", "raid0", "0", 0)}

    if raid in raid_descriptors:
        return raidlevel in raid_descriptors[raid]
    else:
        raise ValueError, "invalid raid level %d" % raid

def get_raid_min_members(raidlevel):
    """Return the minimum number of raid members required for raid level"""
    raid_min_members = {RAID10: 2,
                        RAID6: 4,
                        RAID5: 3,
                        RAID4: 3,
                        RAID1: 2,
                        RAID0: 2}

    for raid, min_members in raid_min_members.items():
        if isRaid(raid, raidlevel):
            return min_members

    raise ValueError, "invalid raid level %d" % raidlevel

def get_raid_max_spares(raidlevel, nummembers):
    """Return the maximum number of raid spares for raidlevel."""
    raid_max_spares = {RAID10: lambda: max(0, nummembers - get_raid_min_members(RAID10)),
                       RAID6: lambda: max(0, nummembers - get_raid_min_members(RAID6)),
                       RAID5: lambda: max(0, nummembers - get_raid_min_members(RAID5)),
                       RAID4: lambda: max(0, nummembers - get_raid_min_members(RAID4)),
                       RAID1: lambda: max(0, nummembers - get_raid_min_members(RAID1)),
                       RAID0: lambda: 0}

    for raid, max_spares_func in raid_max_spares.items():
        if isRaid(raid, raidlevel):
            return max_spares_func()

    raise ValueError, "invalid raid level %d" % raidlevel

def mdadm(args, progress=None):
    rc = iutil.execWithPulseProgress("mdadm", args,
                                     stdout = "/dev/tty5",
                                     stderr = "/dev/tty5",
                                     progress=progress)
    if not rc:
        return

    try:
        msg = open("/tmp/program.log").readlines()[-1].strip()
    except Exception:
        msg = ""

    raise MDRaidError(msg)

def mdcreate(device, level, disks, spares=0, metadataVer=None, bitmap=False,
             progress=None):
    argv = ["--create", device, "--run", "--level=%s" % level]
    raid_devs = len(disks) - spares
    argv.append("--raid-devices=%d" % raid_devs)
    if spares:
        argv.append("--spare-devices=%d" % spares)
    if metadataVer:
        argv.append("--metadata=%s" % metadataVer)
    if bitmap:
        argv.append("--bitmap=internal")
    argv.extend(disks)
    
    try:
        mdadm(argv, progress=progress)
    except MDRaidError as msg:
        raise MDRaidError("mdcreate failed for %s: %s" % (device, msg))

def mddestroy(device):
    args = ["--zero-superblock", device]

    try:
        mdadm(args)
    except MDRaidError as msg:
        raise MDRaidError("mddestroy failed for %s: %s" % (device, msg))

def mdadd(device):
    args = ["--incremental", "--quiet"]
    args.append(device)

    try:
        mdadm(args)
    except MDRaidError as msg:
        raise MDRaidError("mdadd failed for %s: %s" % (device, msg))

def mdactivate(device, members=[], super_minor=None, update_super_minor=False,
               uuid=None):
    if super_minor is None and not uuid:
        raise ValueError("mdactivate requires either a uuid or a super-minor")
    
    if uuid:
        identifier = "--uuid=%s" % uuid
    elif super_minor is not None:
        identifier = "--super-minor=%d" % super_minor
    else:
        identifier = ""

    if update_super_minor:
        extra_args = ["--update=super-minor"]
    else:
        extra_args = [ ]

    args = ["--assemble", device, identifier, "--run", "--auto=md"]
    args += extra_args
    args += members

    try:
        mdadm(args)
    except MDRaidError as msg:
        raise MDRaidError("mdactivate failed for %s: %s" % (device, msg))

def mddeactivate(device):
    args = ["--stop", device]

    try:
        mdadm(args)
    except MDRaidError as msg:
        raise MDRaidError("mddeactivate failed for %s: %s" % (device, msg))

def mdexamine(device):
    vars = iutil.execWithCapture("mdadm",
                                 ["--examine", "--brief", device],
                                 stderr="/dev/tty5").split()

    info = {}
    if vars:
        try:
            info["device"] = vars[1]
            vars = vars[2:]
        except IndexError:
            return {}

    for var in vars:
        (name, equals, value) = var.partition("=")
        if not equals:
            continue

        info[name.lower()] = value.strip()

    return info

1	charliebrady	1.1	#
2			# mdraid.py
3			# mdraid functions
4			#
5			# Copyright (C) 2009 Red Hat, Inc. All rights reserved.
6			#
7			# This program is free software; you can redistribute it and/or modify
8			# it under the terms of the GNU General Public License as published by
9			# the Free Software Foundation; either version 2 of the License, or
10			# (at your option) any later version.
11			#
12			# This program is distributed in the hope that it will be useful,
13			# but WITHOUT ANY WARRANTY; without even the implied warranty of
14			# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15			# GNU General Public License for more details.
16			#
17			# You should have received a copy of the GNU General Public License
18			# along with this program. If not, see <http://www.gnu.org/licenses/>.
19			#
20			# Author(s): Dave Lehman <dlehman@redhat.com>
21			#
22
23			import os
24
25			import iutil
26			from ..errors import *
27
28			import gettext
29			_ = lambda x: gettext.ldgettext("anaconda", x)
30
31			import logging
32			log = logging.getLogger("storage")
33
34			# raidlevels constants
35			RAID10 = 10
36			RAID6 = 6
37			RAID5 = 5
38			RAID4 = 4
39			RAID1 = 1
40			RAID0 = 0
41
42			def getRaidLevels():
43			mdstat_descriptors = {
44			RAID10: ("[RAID10]", "[raid10]"),
45			RAID6: ("[RAID6]", "[raid6]"),
46			RAID5: ("[RAID5]", "[raid5]"),
47			RAID4: ("[RAID4]", "[raid4]"),
48			RAID1: ("[RAID1]", "[raid1]"),
49			RAID0: ("[RAID0]", "[raid0]"),
50			}
51			avail = []
52			try:
53			f = open("/proc/mdstat", "r")
54			except IOError:
55			pass
56			else:
57			for l in f.readlines():
58			if not l.startswith("Personalities"):
59			continue
60
61			lst = l.split()
62
63			for level in mdstat_descriptors:
64			for d in mdstat_descriptors[level]:
65			if d in lst:
66			avail.append(level)
67			break
68
69			f.close()
70
71			avail.sort()
72			return avail
73
74			raid_levels = getRaidLevels()
75
76			def raidLevel(descriptor):
77			for level in raid_levels:
78			if isRaid(level, descriptor):
79			return level
80			else:
81			raise ValueError, "invalid raid level descriptor %s" % descriptor
82
83			def isRaid(raid, raidlevel):
84			"""Return whether raidlevel is a valid descriptor of raid"""
85			raid_descriptors = {RAID10: ("RAID10", "raid10", "10", 10),
86			RAID6: ("RAID6", "raid6", "6", 6),
87			RAID5: ("RAID5", "raid5", "5", 5),
88			RAID4: ("RAID4", "raid4", "4", 4),
89			RAID1: ("mirror", "RAID1", "raid1", "1", 1),
90			RAID0: ("stripe", "RAID0", "raid0", "0", 0)}
91
92			if raid in raid_descriptors:
93			return raidlevel in raid_descriptors[raid]
94			else:
95			raise ValueError, "invalid raid level %d" % raid
96
97			def get_raid_min_members(raidlevel):
98			"""Return the minimum number of raid members required for raid level"""
99			raid_min_members = {RAID10: 2,
100			RAID6: 4,
101			RAID5: 3,
102			RAID4: 3,
103			RAID1: 2,
104			RAID0: 2}
105
106			for raid, min_members in raid_min_members.items():
107			if isRaid(raid, raidlevel):
108			return min_members
109
110			raise ValueError, "invalid raid level %d" % raidlevel
111
112			def get_raid_max_spares(raidlevel, nummembers):
113			"""Return the maximum number of raid spares for raidlevel."""
114			raid_max_spares = {RAID10: lambda: max(0, nummembers - get_raid_min_members(RAID10)),
115			RAID6: lambda: max(0, nummembers - get_raid_min_members(RAID6)),
116			RAID5: lambda: max(0, nummembers - get_raid_min_members(RAID5)),
117			RAID4: lambda: max(0, nummembers - get_raid_min_members(RAID4)),
118			RAID1: lambda: max(0, nummembers - get_raid_min_members(RAID1)),
119			RAID0: lambda: 0}
120
121			for raid, max_spares_func in raid_max_spares.items():
122			if isRaid(raid, raidlevel):
123			return max_spares_func()
124
125			raise ValueError, "invalid raid level %d" % raidlevel
126
127			def mdadm(args, progress=None):
128			rc = iutil.execWithPulseProgress("mdadm", args,
129			stdout = "/dev/tty5",
130			stderr = "/dev/tty5",
131			progress=progress)
132			if not rc:
133			return
134
135			try:
136			msg = open("/tmp/program.log").readlines()[-1].strip()
137			except Exception:
138			msg = ""
139
140			raise MDRaidError(msg)
141
142			def mdcreate(device, level, disks, spares=0, metadataVer=None, bitmap=False,
143			progress=None):
144			argv = ["--create", device, "--run", "--level=%s" % level]
145			raid_devs = len(disks) - spares
146			argv.append("--raid-devices=%d" % raid_devs)
147			if spares:
148			argv.append("--spare-devices=%d" % spares)
149			if metadataVer:
150			argv.append("--metadata=%s" % metadataVer)
151			if bitmap:
152			argv.append("--bitmap=internal")
153			argv.extend(disks)
154
155			try:
156			mdadm(argv, progress=progress)
157			except MDRaidError as msg:
158			raise MDRaidError("mdcreate failed for %s: %s" % (device, msg))
159
160			def mddestroy(device):
161			args = ["--zero-superblock", device]
162
163			try:
164			mdadm(args)
165			except MDRaidError as msg:
166			raise MDRaidError("mddestroy failed for %s: %s" % (device, msg))
167
168			def mdadd(device):
169			args = ["--incremental", "--quiet"]
170			args.append(device)
171
172			try:
173			mdadm(args)
174			except MDRaidError as msg:
175			raise MDRaidError("mdadd failed for %s: %s" % (device, msg))
176
177			def mdactivate(device, members=[], super_minor=None, update_super_minor=False,
178			uuid=None):
179			if super_minor is None and not uuid:
180			raise ValueError("mdactivate requires either a uuid or a super-minor")
181
182			if uuid:
183			identifier = "--uuid=%s" % uuid
184			elif super_minor is not None:
185			identifier = "--super-minor=%d" % super_minor
186			else:
187			identifier = ""
188
189			if update_super_minor:
190			extra_args = ["--update=super-minor"]
191			else:
192			extra_args = [ ]
193
194			args = ["--assemble", device, identifier, "--run", "--auto=md"]
195			args += extra_args
196			args += members
197
198			try:
199			mdadm(args)
200			except MDRaidError as msg:
201			raise MDRaidError("mdactivate failed for %s: %s" % (device, msg))
202
203			def mddeactivate(device):
204			args = ["--stop", device]
205
206			try:
207			mdadm(args)
208			except MDRaidError as msg:
209			raise MDRaidError("mddeactivate failed for %s: %s" % (device, msg))
210
211			def mdexamine(device):
212			vars = iutil.execWithCapture("mdadm",
213			["--examine", "--brief", device],
214			stderr="/dev/tty5").split()
215
216			info = {}
217			if vars:
218			try:
219			info["device"] = vars[1]
220			vars = vars[2:]
221			except IndexError:
222			return {}
223
224			for var in vars:
225			(name, equals, value) = var.partition("=")
226			if not equals:
227			continue
228
229			info[name.lower()] = value.strip()
230
231			return info
232