def mount_one_image(self, fsfile, mountpoint=None):
if os.path.splitext(fsfile)[1] == '.cloop':
blockdev_prefix = 'cloop'
elif os.path.splitext(fsfile)[1] == '.squashfs':
blockdev_prefix = 'loop'
if blockdev_prefix == '':
raise install_misc.InstallStepError(
"No source device found for %s" % fsfile)
dev = ''
sysloops = sorted([
x for x in os.listdir('/sys/block')
if x.startswith(blockdev_prefix)
])
for sysloop in sysloops:
try:
with open(os.path.join('/sys/block', sysloop,
'size')) as sysloopf:
sysloopsize = sysloopf.readline().strip()
if sysloopsize == '0':
if osextras.find_on_path('udevadm'):
udevinfo_cmd = ['udevadm', 'info']
else:
udevinfo_cmd = ['udevinfo']
udevinfo_cmd.extend(
['-q', 'name', '-p',
os.path.join('/block', sysloop)])
with open('/dev/null') as devnull:
udevinfo = subprocess.Popen(udevinfo_cmd,
stdout=subprocess.PIPE,
stderr=devnull,
universal_newlines=True)
devbase = udevinfo.communicate()[0]
if udevinfo.returncode != 0:
devbase = sysloop
dev = '/dev/%s' % devbase
break
except Exception:
continue
if dev == '':
raise install_misc.InstallStepError(
"No loop device available for %s" % fsfile)
misc.execute('losetup', dev, fsfile)
if mountpoint is None:
mountpoint = '/var/lib/ubiquity/%s' % sysloop
if not os.path.isdir(mountpoint):
os.mkdir(mountpoint)
if not misc.execute('mount', dev, mountpoint):
misc.execute('losetup', '-d', dev)
misc.execute('mount', '-o', 'loop', fsfile, mountpoint)
dev = 'unused'
return (dev, mountpoint)
def umount_source(self):
"""umounting loop system from cloop or squashfs system."""
devs = self.devs
devs.reverse()
mountpoints = self.mountpoints
mountpoints.reverse()
for mountpoint in mountpoints:
if not misc.execute('umount', mountpoint):
raise install_misc.InstallStepError("Failed to unmount %s" % mountpoint)
for dev in devs:
if (dev != '' and dev != 'unused' and
not misc.execute('losetup', '-d', dev)):
raise install_misc.InstallStepError(
"Failed to detach loopback device %s" % dev)
def mount_source(self):
"""mounting loop system from cloop or squashfs system."""
self.devs = []
self.mountpoints = []
if not os.path.isdir(self.source):
syslog.syslog('mkdir %s' % self.source)
os.mkdir(self.source)
fs_preseed = self.db.get('ubiquity/install/filesystem-images')
if fs_preseed == '':
# Simple autodetection on unionfs systems
with open('/proc/mounts') as mounts:
for line in mounts:
(device, fstype) = line.split()[1:3]
if fstype == 'squashfs' and os.path.exists(device):
misc.execute('mount', '--bind', device, self.source)
self.mountpoints.append(self.source)
return
# Manual detection on non-unionfs systems
fsfiles = [
os.path.join(self.casper_path, 'filesystem.cloop'),
os.path.join(self.casper_path, 'filesystem.squashfs'),
'/cdrom/META/META.squashfs',
'/live/image/live/filesystem.squashfs'
]
for fsfile in fsfiles:
if fsfile != '' and os.path.isfile(fsfile):
dev, mountpoint = self.mount_one_image(fsfile, self.source)
self.devs.append(dev)
self.mountpoints.append(mountpoint)
elif len(fs_preseed.split()) == 1:
# Just one preseeded image.
if not os.path.isfile(fs_preseed):
raise install_misc.InstallStepError(
"Preseeded filesystem image %s not found" % fs_preseed)
dev, mountpoint = self.mount_one_image(fsfile, self.source)
self.devs.append(dev)
self.mountpoints.append(mountpoint)
else:
# OK, so we need to mount multiple images and unionfs them
# together.
for fsfile in fs_preseed.split():
if not os.path.isfile(fsfile):
raise install_misc.InstallStepError(
"Preseeded filesystem image %s not found" % fsfile)
dev, mountpoint = self.mount_one_image(fsfile)
self.devs.append(dev)
self.mountpoints.append(mountpoint)
assert self.devs
assert self.mountpoints
misc.execute(
'mount', '-t', 'unionfs', '-o',
'dirs=' + ':'.join(['%s=ro' % x for x in self.mountpoints]),
'unionfs', self.source)
self.mountpoints.append(self.source)
