1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
# lvm.py - lvm probing control
#
# Jeremy Katz <katzj@redhat.com>
#
# Copyright 2002 Red Hat, Inc.
#
# This software may be freely redistributed under the terms of the GNU
# general public license.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
import iutil
import os,sys
import string
import math
MAX_LV_SLOTS=256
output = "/tmp/lvmout"
def vgscan():
"""Runs vgscan."""
rc = iutil.execWithRedirect("vgscan",
["vgscan", "-v"],
stdout = output,
stderr = output,
searchPath = 1)
if rc:
raise SystemError, "vgscan failed"
def vgactivate(volgroup = None):
"""Activate volume groups by running vgchange -ay.
volgroup - optional single volume group to activate
"""
args = ["vgchange", "-ay", "-An"]
if volgroup:
args.append(volgroup)
rc = iutil.execWithRedirect(args[0], args,
stdout = output,
stderr = output,
searchPath = 1)
if rc:
raise SystemError, "vgchange failed"
def vgdeactivate(volgroup = None):
"""Deactivate volume groups by running vgchange -an.
volgroup - optional single volume group to deactivate
"""
args = ["vgchange", "-an", "-An"]
if volgroup:
args.append(volgroup)
rc = iutil.execWithRedirect(args[0], args,
stdout = output,
stderr = output,
searchPath = 1)
if rc:
raise SystemError, "vgchange failed"
def lvremove(lvname, vgname):
"""Removes a logical volume.
lvname - name of logical volume to remove.
vgname - name of volume group lv is in.
"""
args = ["lvremove", "-f", "-An"]
dev = "/dev/%s/%s" %(vgname, lvname)
args.append(dev)
rc = iutil.execWithRedirect(args[0], args,
stdout = output,
stderr = output,
searchPath = 1)
if rc:
raise SystemError, "lvremove failed"
def vgremove(vgname):
"""Removes a volume group. Deactivates the volume group first
vgname - name of volume group.
"""
# we'll try to deactivate... if it fails, we'll probably fail on
# the removal too... but it's worth a shot
try:
vgdeactivate(vgname)
except:
pass
args = ["vgremove", vgname]
rc = iutil.execWithRedirect(args[0], args,
stdout = output,
stderr = output,
searchPath = 1)
if rc:
raise SystemError, "vgremove failed"
def getPossiblePhysicalExtents(floor=0):
"""Returns a list of integers representing the possible values for
the physical extent of a volume group. Value is in KB.
floor - size (in KB) of smallest PE we care about.
"""
possiblePE = []
curpe = 8
while curpe <= 16384*1024:
if curpe >= floor:
possiblePE.append(curpe)
curpe = curpe * 2
return possiblePE
def clampLVSizeRequest(size, pe):
"""Given a size and a PE, returns the actual size of logical volumne.
size - size (in MB) of logical volume request
pe - PE size (in KB)
"""
if ((size*1024L) % pe) == 0:
return size
else:
return ((long((size*1024L)/pe)+1L)*pe)/1024
def clampPVSize(pvsize, pesize):
"""Given a PV size and a PE, returns the usable space of the PV.
Takes into account both overhead of the physical volume and 'clamping'
to the PE size.
pvsize - size (in MB) of PV request
pesize - PE size (in KB)
"""
# calculate the number of physical extents. this is size / pesize
# with an appropriate factor for kb/mb matchup
numpes = math.floor(pvsize * 1024 / pesize)
# now, calculate our "real" overhead. 4 bytes for each PE + 128K
overhead = (4 * numpes / 1024) + 128
# now, heuristically, the max of ceil(pesize + 2*overhead) and
# ceil(2*overhead) is greater than the real overhead, so we won't
# get people in a situation where they overcommit the vg
one = math.ceil(pesize + 2 * overhead)
two = math.ceil(2 * overhead)
# now we have to do more unit conversion since our overhead in in KB
if one > two:
usable = pvsize - math.ceil(one / 1024.0)
else:
usable = pvsize - math.ceil(two / 1024.0)
# finally, clamp to being at a pesize boundary
return (long(usable*1024/pesize)*pesize)/1024
def getMaxLVSize(pe):
"""Given a PE size in KB, returns maximum size (in MB) of a logical volume.
pe - PE size in KB
"""
return pe*64
def createSuggestedVGName(partitions):
"""Given list of partition requests, come up with a reasonable VG name
partitions - list of requests
"""
i = 0
while 1:
tmpname = "Volume%02d" % (i,)
if not partitions.isVolumeGroupNameInUse(tmpname):
break
i = i + 1
if i>99:
tmpname = ""
return tmpname
def createSuggestedLVName(logreqs):
"""Given list of LV requests, come up with a reasonable LV name
partitions - list of LV requests for this VG
"""
i = 0
lnames = []
for lv in logreqs:
lnames.append(lv.logicalVolumeName)
while 1:
tmpname = "LogVol%02d" % (i,)
if (logreqs is None) or (tmpname not in lnames):
break
i = i + 1
if i>99:
tmpname = ""
return tmpname
|
