import os
import re
-import uuid
import tempfile
-import time
+import uuid
from collections import namedtuple
import parted
from image_creator.rsync import Rsync
from image_creator.util import get_command
from image_creator.util import FatalError
+from image_creator.util import try_fail_repeat
+from image_creator.util import free_space
+from image_creator.gpt import GPTPartitionTable
findfs = get_command('findfs')
-truncate = get_command('truncate')
dd = get_command('dd')
dmsetup = get_command('dmsetup')
losetup = get_command('losetup')
mount = get_command('mount')
umount = get_command('umount')
blkid = get_command('blkid')
-
-MKFS_OPTS = {
- 'ext2': ['-F'],
- 'ext3': ['-F'],
- 'ext4': ['-F'],
- 'reiserfs': ['-ff'],
- 'btrfs': [],
- 'minix': [],
- 'xfs': ['-f'],
- 'jfs': ['-f'],
- 'ntfs': ['-F'],
- 'msdos': [],
- 'vfat': []
- }
-
-
-class BundleVolume():
-
- def __init__(self, out, meta):
+tune2fs = get_command('tune2fs')
+
+MKFS_OPTS = {'ext2': ['-F'],
+ 'ext3': ['-F'],
+ 'ext4': ['-F'],
+ 'reiserfs': ['-ff'],
+ 'btrfs': [],
+ 'minix': [],
+ 'xfs': ['-f'],
+ 'jfs': ['-f'],
+ 'ntfs': ['-F'],
+ 'msdos': [],
+ 'vfat': []}
+
+
+class BundleVolume(object):
+ """This class can be used to create an image out of the running system"""
+
+ def __init__(self, out, meta, tmp=None):
+ """Create an instance of the BundleVolume class."""
self.out = out
self.meta = meta
+ self.tmp = tmp
self.out.output('Searching for root device ...', False)
root = self._get_root_partition()
self.disk = parted.Disk(device)
def _read_fstable(self, f):
+ """Use this generator to iterate over the lines of and fstab file"""
if not os.path.isfile(f):
raise FatalError("Unable to open: `%s'. File is missing." % f)
FileSystemTableEntry = namedtuple('FileSystemTableEntry',
- 'dev mpoint fs opts freq passno')
+ 'dev mpoint fs opts freq passno')
with open(f) as table:
for line in iter(table):
entry = line.split('#')[0].strip().split()
yield FileSystemTableEntry(*entry)
def _get_root_partition(self):
+ """Return the fstab entry accosiated with the root filesystem"""
for entry in self._read_fstable('/etc/fstab'):
if entry.mpoint == '/':
return entry.dev
raise FatalError("Unable to find root device in /etc/fstab")
def _is_mpoint(self, path):
+ """Check if a directory is currently a mount point"""
for entry in self._read_fstable('/proc/mounts'):
if entry.mpoint == path:
return True
return False
def _get_mount_options(self, device):
+ """Return the mount entry associated with a mounted device"""
for entry in self._read_fstable('/proc/mounts'):
if not entry.dev.startswith('/'):
continue
return None
def _create_partition_table(self, image):
-
- if self.disk.type != 'msdos':
- raise FatalError('Only msdos partition tables are supported')
+ """Copy the partition table of the host system into the image"""
# Copy the MBR and the space between the MBR and the first partition.
- # In Grub version 1 Stage 1.5 is located there.
+ # In msdos partition tables Grub Stage 1.5 is located there.
+ # In gpt partition tables the Primary GPT Header is there.
first_sector = self.disk.getPrimaryPartitions()[0].geometry.start
dd('if=%s' % self.disk.device.path, 'of=%s' % image,
'bs=%d' % self.disk.device.sectorSize,
'count=%d' % first_sector, 'conv=notrunc')
+ if self.disk.type == 'gpt':
+ # Copy the Secondary GPT Header
+ table = GPTPartitionTable(self.disk.device.path)
+ dd('if=%s' % self.disk.device.path, 'of=%s' % image,
+ 'bs=%d' % self.disk.device.sectorSize, 'conv=notrunc',
+ 'seek=%d' % table.primary.last_usable_lba,
+ 'skip=%d' % table.primary.last_usable_lba)
+
# Create the Extended boot records (EBRs) in the image
extended = self.disk.getExtendedPartition()
if not extended:
start = logical[i].geometry.end + 1
def _get_partitions(self, disk):
+ """Returns a list with the partitions of the provided disk"""
Partition = namedtuple('Partition', 'num start end type fs')
partitions = []
return partitions
def _shrink_partitions(self, image):
+ """Remove the last partition of the image if it is a swap partition and
+ shrink the partition before that. Make sure it can still host all the
+ files the corresponding host file system hosts
+ """
+ new_end = self.disk.device.length
- new_end = self.disk.device.getLength()
-
- image_dev = parted.Device(image)
- image_disk = parted.Disk(image_dev)
+ image_disk = parted.Disk(parted.Device(image))
is_extended = lambda p: p.type == parted.PARTITION_EXTENDED
is_logical = lambda p: p.type == parted.PARTITION_LOGICAL
image_disk.deletePartition(
image_disk.getPartitionBySector(last.start))
- image_disk.commit()
+ image_disk.commitToDevice()
if is_logical(last) and last.num == 5:
extended = image_disk.getExtendedPartition()
image_disk.deletePartition(extended)
- image_disk.commit()
+ image_disk.commitToDevice()
partitions.remove(filter(is_extended, partitions)[0])
partitions.remove(last)
last = partitions[-1]
- # Leave 2048 blocks at the end
- new_end = last.end + 2048
+ new_end = last.end
mount_options = self._get_mount_options(
- self.disk.getPartitionBySector(last.start).path)
+ self.disk.getPartitionBySector(last.start).path)
if mount_options is not None:
stat = os.statvfs(mount_options.mpoint)
# Shrink the last partition. The new size should be the size of the
# Add 10% just to be on the safe side
part_end = last.start + (new_size * 11) // 10
- # Alighn to 2048
+ # Align to 2048
part_end = ((part_end + 2047) // 2048) * 2048
+ # Make sure the partition starts where the old partition started.
+ constraint = parted.Constraint(device=image_disk.device)
+ constraint.startRange = parted.Geometry(device=image_disk.device,
+ start=last.start, length=1)
+
image_disk.setPartitionGeometry(
- image_disk.getPartitionBySector(last.start),
- parted.Constraint(device=image_disk.device),
- start=last.start, end=last.end)
- image_disk.commit()
+ image_disk.getPartitionBySector(last.start), constraint,
+ start=last.start, end=part_end)
+ image_disk.commitToDevice()
# Parted may have changed this for better alignment
part_end = image_disk.getPartitionBySector(last.start).geometry.end
last = last._replace(end=part_end)
partitions[-1] = last
- # Leave 2048 blocks at the end.
- new_end = new_size + 2048
+ new_end = part_end
if last.type == parted.PARTITION_LOGICAL:
# Fix the extended partition
- extended = disk.getExtendedPartition()
+ image_disk.minimizeExtendedPartition()
- image_disk.setPartitionGeometry(extended,
- parted.Constraint(device=img_dev),
- ext.geometry.start, end=last.end)
- image_disk.commit()
-
- return new_end
+ return (new_end, self._get_partitions(image_disk))
def _map_partition(self, dev, num, start, end):
- name = os.path.basename(dev)
+ """Map a partition into a block device using the device mapper"""
+ name = os.path.basename(dev) + "_" + uuid.uuid4().hex
tablefd, table = tempfile.mkstemp()
try:
size = end - start + 1
return "/dev/mapper/%sp%d" % (name, num)
def _unmap_partition(self, dev):
+ """Unmap a previously mapped partition"""
if not os.path.exists(dev):
return
- dmsetup('remove', dev.split('/dev/mapper/')[1])
- time.sleep(0.1)
+ try_fail_repeat(dmsetup, 'remove', dev.split('/dev/mapper/')[1])
def _mount(self, target, devs):
-
+ """Mount a list of filesystems in mountpoints relative to target"""
devs.sort(key=lambda d: d[1])
- for dev, mpoint in devs:
+ for dev, mpoint, options in devs:
absmpoint = os.path.abspath(target + mpoint)
if not os.path.exists(absmpoint):
os.makedirs(absmpoint)
- mount(dev, absmpoint)
+
+ if len(options) > 0:
+ mount(dev, absmpoint, '-o', ",".join(options))
+ else:
+ mount(dev, absmpoint)
def _umount_all(self, target):
+ """Unmount all filesystems that are mounted under the directory target
+ """
mpoints = []
for entry in self._read_fstable('/proc/mounts'):
if entry.mpoint.startswith(os.path.abspath(target)):
mpoints.sort()
for mpoint in reversed(mpoints):
- umount(mpoint)
+ try_fail_repeat(umount, mpoint)
def _to_exclude(self):
+ """Find which directories to exclude during the image copy. This is
+ accompliced by checking which directories serve as mount points for
+ virtual file systems
+ """
excluded = ['/tmp', '/var/tmp']
+ if self.tmp is not None:
+ excluded.append(self.tmp)
local_filesystems = MKFS_OPTS.keys() + ['rootfs']
for entry in self._read_fstable('/proc/mounts'):
if entry.fs in local_filesystems:
if mpoint in excluded:
continue
- descendants = filter(lambda p: p.startswith(mpoint + '/'),
- excluded)
+ descendants = filter(
+ lambda p: p.startswith(mpoint + '/'), excluded)
if len(descendants):
for d in descendants:
excluded.remove(d)
if not found_ancestor:
excluded.append(mpoint)
- return map(lambda d: d + "/*", excluded)
+ return excluded
def _replace_uuids(self, target, new_uuid):
+ """Replace UUID references in various files. This is needed after
+ copying system files of the host into a new filesystem
+ """
files = ['/etc/fstab',
'/boot/grub/grub.cfg',
'/boot/grub/menu.lst',
'/boot/grub/grub.conf']
- orig = dict(map(lambda p: (p.number, blkid( '-s', 'UUID', '-o',
- 'value', p.path).stdout.strip()), self.disk.partitions))
+ orig = {}
+ for p in self.disk.partitions:
+ if p.number in new_uuid.keys():
+ orig[p.number] = \
+ blkid('-s', 'UUID', '-o', 'value', p.path).stdout.strip()
for f in map(lambda f: target + f, files):
-
if not os.path.exists(f):
continue
line = re.sub(orig[i], uuid, line)
dest.write(line)
- def _create_filesystems(self, image):
+ def _create_filesystems(self, image, partitions):
+ """Fill the image with data. Host file systems that are not currently
+ mounted are binary copied into the image. For mounted file systems, a
+ file system level copy is performed.
+ """
filesystem = {}
+ orig_dev = {}
for p in self.disk.partitions:
filesystem[p.number] = self._get_mount_options(p.path)
+ orig_dev[p.number] = p.path
- partitions = self._get_partitions(parted.Disk(parted.Device(image)))
unmounted = filter(lambda p: filesystem[p.num] is None, partitions)
mounted = filter(lambda p: filesystem[p.num] is not None, partitions)
# For partitions that are not mounted right now, we can simply dd them
# into the image.
for p in unmounted:
+ self.out.output('Cloning partition %d ... ' % p.num, False)
dd('if=%s' % self.disk.device.path, 'of=%s' % image,
'count=%d' % (p.end - p.start + 1), 'conv=notrunc',
'seek=%d' % p.start, 'skip=%d' % p.start)
+ self.out.success("done")
loop = str(losetup('-f', '--show', image)).strip()
+
+ # Recreate mounted file systems
mapped = {}
try:
for p in mounted:
for i, dev in mapped.iteritems():
fs = filesystem[i].fs
self.out.output('Creating %s filesystem on partition %d ... ' %
- (fs, i), False)
+ (fs, i), False)
get_command('mkfs.%s' % fs)(*(MKFS_OPTS[fs] + [dev]))
+
+ # For ext[234] enable the default mount options
+ if re.match('^ext[234]$', fs):
+ mopts = filter(
+ lambda p: p.startswith('Default mount options:'),
+ tune2fs('-l', orig_dev[i]).splitlines()
+ )[0].split(':')[1].strip().split()
+
+ if not (len(mopts) == 1 and mopts[0] == '(none)'):
+ for opt in mopts:
+ tune2fs('-o', opt, dev)
+
self.out.success('done')
- new_uuid[i] = blkid('-s', 'UUID', '-o', 'value', dev
- ).stdout.strip()
+ new_uuid[i] = blkid(
+ '-s', 'UUID', '-o', 'value', dev).stdout.strip()
target = tempfile.mkdtemp()
+ devs = []
+ for i in mapped.keys():
+ fs = filesystem[i].fs
+ mpoint = filesystem[i].mpoint
+ opts = []
+ for opt in filesystem[i].opts.split(','):
+ if opt in ('acl', 'user_xattr'):
+ opts.append(opt)
+ devs.append((mapped[i], mpoint, opts))
try:
- absmpoints = self._mount(target,
- [(mapped[i], filesystem[i].mpoint) for i in mapped.keys()]
- )
- exclude = self._to_exclude() + [image]
- rsync = Rsync('/', target,
- map(lambda p: os.path.relpath(p, '/'), exclude))
- msg = "Copying host files into the image"
- rsync.archive().run(self.out, msg)
-
+ self._mount(target, devs)
+
+ excluded = self._to_exclude()
+
+ rsync = Rsync(self.out)
+
+ for excl in excluded + [image]:
+ rsync.exclude(excl)
+
+ rsync.archive().hard_links().xattrs().sparse().acls()
+ rsync.run('/', target, 'host', 'temporary image')
+
+ # Create missing mountpoints. Since they are mountpoints, we
+ # cannot determine the ownership and the mode of the real
+ # directory. Make them inherit those properties from their
+ # parent dir
+ for excl in excluded:
+ dirname = os.path.dirname(excl)
+ stat = os.stat(dirname)
+ os.mkdir(target + excl)
+ os.chmod(target + excl, stat.st_mode)
+ os.chown(target + excl, stat.st_uid, stat.st_gid)
+
+ # /tmp and /var/tmp are special cases. We exclude then even if
+ # they aren't mountpoints. Restore their permissions.
+ for excl in ('/tmp', '/var/tmp'):
+ if self._is_mpoint(excl):
+ os.chmod(target + excl, 041777)
+ os.chown(target + excl, 0, 0)
+ else:
+ stat = os.stat(excl)
+ os.chmod(target + excl, stat.st_mode)
+ os.chown(target + excl, stat.st_uid, stat.st_gid)
+
+ # We need to replace the old UUID referencies with the new
+ # ones in grub configuration files and /etc/fstab for file
+ # systems that have been recreated.
self._replace_uuids(target, new_uuid)
finally:
self._unmap_partition(dev)
losetup('-d', loop)
- def create_image(self):
-
- image = '/mnt/%s.diskdump' % uuid.uuid4().hex
+ def create_image(self, image):
+ """Given an image filename, this method will create an image out of the
+ running system.
+ """
- disk_size = self.disk.device.getLength() * self.disk.device.sectorSize
+ size = self.disk.device.length * self.disk.device.sectorSize
# Create sparse file to host the image
- truncate("-s", "%d" % disk_size, image)
+ fd = os.open(image, os.O_WRONLY | os.O_CREAT)
+ try:
+ os.ftruncate(fd, size)
+ finally:
+ os.close(fd)
self._create_partition_table(image)
+ end_sector, partitions = self._shrink_partitions(image)
+
+ if self.disk.type == 'gpt':
+ old_size = size
+ size = (end_sector + 1) * self.disk.device.sectorSize
+ ptable = GPTPartitionTable(image)
+ size = ptable.shrink(size, old_size)
+ else:
+ # Alighn to 2048
+ end_sector = ((end_sector + 2047) // 2048) * 2048
+ size = (end_sector + 1) * self.disk.device.sectorSize
- end_sector = self._shrink_partitions(image)
+ # Truncate image to the new size.
+ fd = os.open(image, os.O_RDWR)
+ try:
+ os.ftruncate(fd, size)
+ finally:
+ os.close(fd)
# Check if the available space is enough to host the image
dirname = os.path.dirname(image)
- size = (end_sector + 1) * self.disk.device.sectorSize
- self.out.output("Examining available space in %s ..." % dirname, False)
- stat = os.statvfs(dirname)
- available = stat.f_bavail * stat.f_frsize
- if available <= size:
- raise FatalError('Not enough space in %s to host the image' %
- dirname)
+ self.out.output("Examining available space ...", False)
+ if free_space(dirname) <= size:
+ raise FatalError("Not enough space under %s to host the temporary "
+ "image" % dirname)
self.out.success("sufficient")
- self._create_filesystems(image)
+ self._create_filesystems(image, partitions)
return image
projects / snf-image-creator / blobdiff