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1#!/usr/bin/env python -tt
2#
3# Copyright (c) 2009, 2010, 2011 Intel, Inc.
4# Copyright (c) 2007, 2008 Red Hat, Inc.
5# Copyright (c) 2008 Daniel P. Berrange
6# Copyright (c) 2008 David P. Huff
7#
8# This program is free software; you can redistribute it and/or modify it
9# under the terms of the GNU General Public License as published by the Free
10# Software Foundation; version 2 of the License
11#
12# This program is distributed in the hope that it will be useful, but
13# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14# or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15# for more details.
16#
17# You should have received a copy of the GNU General Public License along
18# with this program; if not, write to the Free Software Foundation, Inc., 59
19# Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20
21import os
22
23from wic import msger
24from wic.utils import runner
25from wic.utils.errors import ImageError
26from wic.utils.fs_related import *
27from wic.utils.oe.misc import *
28
29# Overhead of the MBR partitioning scheme (just one sector)
30MBR_OVERHEAD = 1
31
32# Size of a sector in bytes
33SECTOR_SIZE = 512
34
35class Image:
36 """
37 Generic base object for an image.
38
39 An Image is a container for a set of DiskImages and associated
40 partitions.
41 """
42 def __init__(self):
43 self.disks = {}
44 self.partitions = []
45 self.parted = find_binary_path("parted")
46 # Size of a sector used in calculations
47 self.sector_size = SECTOR_SIZE
48 self._partitions_layed_out = False
49
50 def __add_disk(self, disk_name):
51 """ Add a disk 'disk_name' to the internal list of disks. Note,
52 'disk_name' is the name of the disk in the target system
53 (e.g., sdb). """
54
55 if disk_name in self.disks:
56 # We already have this disk
57 return
58
59 assert not self._partitions_layed_out
60
61 self.disks[disk_name] = \
62 { 'disk': None, # Disk object
63 'numpart': 0, # Number of allocate partitions
64 'partitions': [], # Indexes to self.partitions
65 'offset': 0, # Offset of next partition (in sectors)
66 # Minimum required disk size to fit all partitions (in bytes)
67 'min_size': 0,
68 'ptable_format': "msdos" } # Partition table format
69
70 def add_disk(self, disk_name, disk_obj):
71 """ Add a disk object which have to be partitioned. More than one disk
72 can be added. In case of multiple disks, disk partitions have to be
73 added for each disk separately with 'add_partition()". """
74
75 self.__add_disk(disk_name)
76 self.disks[disk_name]['disk'] = disk_obj
77
78 def __add_partition(self, part):
79 """ This is a helper function for 'add_partition()' which adds a
80 partition to the internal list of partitions. """
81
82 assert not self._partitions_layed_out
83
84 self.partitions.append(part)
85 self.__add_disk(part['disk_name'])
86
87 def add_partition(self, size, disk_name, mountpoint, source_file = None, fstype = None,
88 label=None, fsopts = None, boot = False, align = None,
89 part_type = None):
90 """ Add the next partition. Prtitions have to be added in the
91 first-to-last order. """
92
93 ks_pnum = len(self.partitions)
94
95 # Converting MB to sectors for parted
96 size = size * 1024 * 1024 / self.sector_size
97
98 # We still need partition for "/" or non-subvolume
99 if mountpoint == "/" or not fsopts:
100 part = { 'ks_pnum' : ks_pnum, # Partition number in the KS file
101 'size': size, # In sectors
102 'mountpoint': mountpoint, # Mount relative to chroot
103 'source_file': source_file, # partition contents
104 'fstype': fstype, # Filesystem type
105 'fsopts': fsopts, # Filesystem mount options
106 'label': label, # Partition label
107 'disk_name': disk_name, # physical disk name holding partition
108 'device': None, # kpartx device node for partition
109 'num': None, # Partition number
110 'boot': boot, # Bootable flag
111 'align': align, # Partition alignment
112 'part_type' : part_type } # Partition type
113
114 self.__add_partition(part)
115
116 def layout_partitions(self, ptable_format = "msdos"):
117 """ Layout the partitions, meaning calculate the position of every
118 partition on the disk. The 'ptable_format' parameter defines the
119 partition table format and may be "msdos". """
120
121 msger.debug("Assigning %s partitions to disks" % ptable_format)
122
123 if ptable_format not in ('msdos'):
124 raise ImageError("Unknown partition table format '%s', supported " \
125 "formats are: 'msdos'" % ptable_format)
126
127 if self._partitions_layed_out:
128 return
129
130 self._partitions_layed_out = True
131
132 # Go through partitions in the order they are added in .ks file
133 for n in range(len(self.partitions)):
134 p = self.partitions[n]
135
136 if not self.disks.has_key(p['disk_name']):
137 raise ImageError("No disk %s for partition %s" \
138 % (p['disk_name'], p['mountpoint']))
139
140 if p['part_type']:
141 # The --part-type can also be implemented for MBR partitions,
142 # in which case it would map to the 1-byte "partition type"
143 # filed at offset 3 of the partition entry.
144 raise ImageError("setting custom partition type is not " \
145 "implemented for msdos partitions")
146
147 # Get the disk where the partition is located
148 d = self.disks[p['disk_name']]
149 d['numpart'] += 1
150 d['ptable_format'] = ptable_format
151
152 if d['numpart'] == 1:
153 if ptable_format == "msdos":
154 overhead = MBR_OVERHEAD
155
156 # Skip one sector required for the partitioning scheme overhead
157 d['offset'] += overhead
158
159 if p['align']:
160 # If not first partition and we do have alignment set we need
161 # to align the partition.
162 # FIXME: This leaves a empty spaces to the disk. To fill the
163 # gaps we could enlargea the previous partition?
164
165 # Calc how much the alignment is off.
166 align_sectors = d['offset'] % (p['align'] * 1024 / self.sector_size)
167
168 if align_sectors:
169 # If partition is not aligned as required, we need
170 # to move forward to the next alignment point
171 align_sectors = (p['align'] * 1024 / self.sector_size) - align_sectors
172
173 msger.debug("Realignment for %s%s with %s sectors, original"
174 " offset %s, target alignment is %sK." %
175 (p['disk_name'], d['numpart'], align_sectors,
176 d['offset'], p['align']))
177
178 # increase the offset so we actually start the partition on right alignment
179 d['offset'] += align_sectors
180
181 p['start'] = d['offset']
182 d['offset'] += p['size']
183
184 p['type'] = 'primary'
185 p['num'] = d['numpart']
186
187 if d['ptable_format'] == "msdos":
188 if d['numpart'] > 2:
189 # Every logical partition requires an additional sector for
190 # the EBR, so steal the last sector from the end of each
191 # partition starting from the 3rd one for the EBR. This
192 # will make sure the logical partitions are aligned
193 # correctly.
194 p['size'] -= 1
195
196 if d['numpart'] > 3:
197 p['type'] = 'logical'
198 p['num'] = d['numpart'] + 1
199
200 d['partitions'].append(n)
201 msger.debug("Assigned %s to %s%d, sectors range %d-%d size %d "
202 "sectors (%d bytes)." \
203 % (p['mountpoint'], p['disk_name'], p['num'],
204 p['start'], p['start'] + p['size'] - 1,
205 p['size'], p['size'] * self.sector_size))
206
207 # Once all the partitions have been layed out, we can calculate the
208 # minumim disk sizes.
209 for disk_name, d in self.disks.items():
210 d['min_size'] = d['offset']
211
212 d['min_size'] *= self.sector_size
213
214 def __run_parted(self, args):
215 """ Run parted with arguments specified in the 'args' list. """
216
217 args.insert(0, self.parted)
218 msger.debug(args)
219
220 rc, out = runner.runtool(args, catch = 3)
221 out = out.strip()
222 if out:
223 msger.debug('"parted" output: %s' % out)
224
225 if rc != 0:
226 # We don't throw exception when return code is not 0, because
227 # parted always fails to reload part table with loop devices. This
228 # prevents us from distinguishing real errors based on return
229 # code.
230 msger.error("WARNING: parted returned '%s' instead of 0 (use --debug for details)" % rc)
231
232 def __create_partition(self, device, parttype, fstype, start, size):
233 """ Create a partition on an image described by the 'device' object. """
234
235 # Start is included to the size so we need to substract one from the end.
236 end = start + size - 1
237 msger.debug("Added '%s' partition, sectors %d-%d, size %d sectors" %
238 (parttype, start, end, size))
239
240 args = ["-s", device, "unit", "s", "mkpart", parttype]
241 if fstype:
242 args.extend([fstype])
243 args.extend(["%d" % start, "%d" % end])
244
245 return self.__run_parted(args)
246
247 def __format_disks(self):
248 self.layout_partitions()
249
250 for dev in self.disks.keys():
251 d = self.disks[dev]
252 msger.debug("Initializing partition table for %s" % \
253 (d['disk'].device))
254 self.__run_parted(["-s", d['disk'].device, "mklabel",
255 d['ptable_format']])
256
257 msger.debug("Creating partitions")
258
259 for p in self.partitions:
260 d = self.disks[p['disk_name']]
261 if d['ptable_format'] == "msdos" and p['num'] == 5:
262 # The last sector of the 3rd partition was reserved for the EBR
263 # of the first _logical_ partition. This is why the extended
264 # partition should start one sector before the first logical
265 # partition.
266 self.__create_partition(d['disk'].device, "extended",
267 None, p['start'] - 1,
268 d['offset'] - p['start'])
269
270 if p['fstype'] == "swap":
271 parted_fs_type = "linux-swap"
272 elif p['fstype'] == "vfat":
273 parted_fs_type = "fat32"
274 elif p['fstype'] == "msdos":
275 parted_fs_type = "fat16"
276 else:
277 # Type for ext2/ext3/ext4/btrfs
278 parted_fs_type = "ext2"
279
280 # Boot ROM of OMAP boards require vfat boot partition to have an
281 # even number of sectors.
282 if p['mountpoint'] == "/boot" and p['fstype'] in ["vfat", "msdos"] \
283 and p['size'] % 2:
284 msger.debug("Substracting one sector from '%s' partition to " \
285 "get even number of sectors for the partition" % \
286 p['mountpoint'])
287 p['size'] -= 1
288
289 self.__create_partition(d['disk'].device, p['type'],
290 parted_fs_type, p['start'], p['size'])
291
292 if p['boot']:
293 flag_name = "boot"
294 msger.debug("Set '%s' flag for partition '%s' on disk '%s'" % \
295 (flag_name, p['num'], d['disk'].device))
296 self.__run_parted(["-s", d['disk'].device, "set",
297 "%d" % p['num'], flag_name, "on"])
298
299 # Parted defaults to enabling the lba flag for fat16 partitions,
300 # which causes compatibility issues with some firmware (and really
301 # isn't necessary).
302 if parted_fs_type == "fat16":
303 if d['ptable_format'] == 'msdos':
304 msger.debug("Disable 'lba' flag for partition '%s' on disk '%s'" % \
305 (p['num'], d['disk'].device))
306 self.__run_parted(["-s", d['disk'].device, "set",
307 "%d" % p['num'], "lba", "off"])
308
309 def cleanup(self):
310 if self.disks:
311 for dev in self.disks.keys():
312 d = self.disks[dev]
313 try:
314 d['disk'].cleanup()
315 except:
316 pass
317
318 def __write_partition(self, num, source_file, start, size):
319 """
320 Install source_file contents into a partition.
321 """
322 if not source_file: # nothing to write
323 return
324
325 # Start is included in the size so need to substract one from the end.
326 end = start + size - 1
327 msger.debug("Installed %s in partition %d, sectors %d-%d, size %d sectors" % (source_file, num, start, end, size))
328
329 dd_cmd = "dd if=%s of=%s bs=%d seek=%d count=%d conv=notrunc" % \
330 (source_file, self.image_file, self.sector_size, start, size)
331 exec_cmd(dd_cmd)
332
333
334 def assemble(self, image_file):
335 msger.debug("Installing partitions")
336
337 self.image_file = image_file
338
339 for p in self.partitions:
340 d = self.disks[p['disk_name']]
341 if d['ptable_format'] == "msdos" and p['num'] == 5:
342 # The last sector of the 3rd partition was reserved for the EBR
343 # of the first _logical_ partition. This is why the extended
344 # partition should start one sector before the first logical
345 # partition.
346 self.__write_partition(p['num'], p['source_file'],
347 p['start'] - 1,
348 d['offset'] - p['start'])
349
350 self.__write_partition(p['num'], p['source_file'],
351 p['start'], p['size'])
352
353 def create(self):
354 for dev in self.disks.keys():
355 d = self.disks[dev]
356 d['disk'].create()
357
358 self.__format_disks()
359
360 return