1 files changed, 782 insertions, 0 deletions

diff --git a/scripts/lib/mic/utils/partitionedfs.py b/scripts/lib/mic/utils/partitionedfs.py
new file mode 100644
index 0000000000..6607466a83
--- /dev/null
+++ b/scripts/lib/mic/utils/partitionedfs.py
@@ -0,0 +1,782 @@
+#!/usr/bin/python -tt
+#
+# Copyright (c) 2009, 2010, 2011 Intel, Inc.
+# Copyright (c) 2007, 2008 Red Hat, Inc.
+# Copyright (c) 2008 Daniel P. Berrange
+# Copyright (c) 2008 David P. Huff
+#
+# 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; version 2 of the License
+#
+# 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, write to the Free Software Foundation, Inc., 59
+# Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+import os
+
+from mic import msger
+from mic.utils import runner
+from mic.utils.errors import MountError
+from mic.utils.fs_related import *
+from mic.utils.gpt_parser import GptParser
+from mic.utils.oe.misc import *
+
+# Overhead of the MBR partitioning scheme (just one sector)
+MBR_OVERHEAD = 1
+# Overhead of the GPT partitioning scheme
+GPT_OVERHEAD = 34
+
+# Size of a sector in bytes
+SECTOR_SIZE = 512
+
+class PartitionedMount(Mount):
+    def __init__(self, mountdir, skipformat = False):
+        Mount.__init__(self, mountdir)
+        self.disks = {}
+        self.partitions = []
+        self.subvolumes = []
+        self.mapped = False
+        self.mountOrder = []
+        self.unmountOrder = []
+        self.parted = find_binary_path("parted")
+        self.btrfscmd=None
+        self.skipformat = skipformat
+        self.snapshot_created = self.skipformat
+        # Size of a sector used in calculations
+        self.sector_size = SECTOR_SIZE
+        self._partitions_layed_out = False
+
+    def __add_disk(self, disk_name):
+        """ Add a disk 'disk_name' to the internal list of disks. Note,
+        'disk_name' is the name of the disk in the target system
+        (e.g., sdb). """
+
+        if disk_name in self.disks:
+            # We already have this disk
+            return
+
+        assert not self._partitions_layed_out
+
+        self.disks[disk_name] = \
+                { 'disk': None,     # Disk object
+                  'mapped': False,  # True if kpartx mapping exists
+                  'numpart': 0,     # Number of allocate partitions
+                  'partitions': [], # Indexes to self.partitions
+                  'offset': 0,      # Offset of next partition (in sectors)
+                  # Minimum required disk size to fit all partitions (in bytes)
+                  'min_size': 0,
+                  'ptable_format': "msdos" } # Partition table format
+
+    def add_disk(self, disk_name, disk_obj):
+        """ Add a disk object which have to be partitioned. More than one disk
+        can be added. In case of multiple disks, disk partitions have to be
+        added for each disk separately with 'add_partition()". """
+
+        self.__add_disk(disk_name)
+        self.disks[disk_name]['disk'] = disk_obj
+
+    def __add_partition(self, part):
+        """ This is a helper function for 'add_partition()' which adds a
+        partition to the internal list of partitions. """
+
+        assert not self._partitions_layed_out
+
+        self.partitions.append(part)
+        self.__add_disk(part['disk_name'])
+
+    def add_partition(self, size, disk_name, mountpoint, source_file = None, fstype = None,
+                      label=None, fsopts = None, boot = False, align = None,
+                      part_type = None):
+        """ Add the next partition. Prtitions have to be added in the
+        first-to-last order. """
+
+        ks_pnum = len(self.partitions)
+
+        # Converting MB to sectors for parted
+        size = size * 1024 * 1024 / self.sector_size
+
+        # We need to handle subvolumes for btrfs
+        if fstype == "btrfs" and fsopts and fsopts.find("subvol=") != -1:
+            self.btrfscmd=find_binary_path("btrfs")
+            subvol = None
+            opts = fsopts.split(",")
+            for opt in opts:
+                if opt.find("subvol=") != -1:
+                    subvol = opt.replace("subvol=", "").strip()
+                    break
+            if not subvol:
+                raise MountError("No subvolume: %s" % fsopts)
+            self.subvolumes.append({'size': size, # In sectors
+                                    'mountpoint': mountpoint, # Mount relative to chroot
+                                    'fstype': fstype, # Filesystem type
+                                    'fsopts': fsopts, # Filesystem mount options
+                                    'disk_name': disk_name, # physical disk name holding partition
+                                    'device': None, # kpartx device node for partition
+                                    'mount': None, # Mount object
+                                    'subvol': subvol, # Subvolume name
+                                    'boot': boot, # Bootable flag
+                                    'mounted': False # Mount flag
+                                   })
+
+        # We still need partition for "/" or non-subvolume
+        if mountpoint == "/" or not fsopts or fsopts.find("subvol=") == -1:
+            # Don't need subvolume for "/" because it will be set as default subvolume
+            if fsopts and fsopts.find("subvol=") != -1:
+                opts = fsopts.split(",")
+                for opt in opts:
+                    if opt.strip().startswith("subvol="):
+                        opts.remove(opt)
+                        break
+                fsopts = ",".join(opts)
+
+            part = { 'ks_pnum' : ks_pnum, # Partition number in the KS file
+                     'size': size, # In sectors
+                     'mountpoint': mountpoint, # Mount relative to chroot
+                     'source_file': source_file, # partition contents
+                     'fstype': fstype, # Filesystem type
+                     'fsopts': fsopts, # Filesystem mount options
+                     'label': label, # Partition label
+                     'disk_name': disk_name, # physical disk name holding partition
+                     'device': None, # kpartx device node for partition
+                     'mount': None, # Mount object
+                     'num': None, # Partition number
+                     'boot': boot, # Bootable flag
+                     'align': align, # Partition alignment
+                     'part_type' : part_type, # Partition type
+                     'partuuid': None } # Partition UUID (GPT-only)
+
+            self.__add_partition(part)
+
+    def layout_partitions(self, ptable_format = "msdos"):
+        """ Layout the partitions, meaning calculate the position of every
+        partition on the disk. The 'ptable_format' parameter defines the
+        partition table format, and may be either "msdos" or "gpt". """
+
+        msger.debug("Assigning %s partitions to disks" % ptable_format)
+
+        if ptable_format not in ('msdos', 'gpt'):
+            raise MountError("Unknown partition table format '%s', supported " \
+                             "formats are: 'msdos' and 'gpt'" % ptable_format)
+
+        if self._partitions_layed_out:
+            return
+
+        self._partitions_layed_out = True
+
+        # Go through partitions in the order they are added in .ks file
+        for n in range(len(self.partitions)):
+            p = self.partitions[n]
+
+            if not self.disks.has_key(p['disk_name']):
+                raise MountError("No disk %s for partition %s" \
+                                 % (p['disk_name'], p['mountpoint']))
+
+            if p['part_type'] and ptable_format != 'gpt':
+                # The --part-type can also be implemented for MBR partitions,
+                # in which case it would map to the 1-byte "partition type"
+                # filed at offset 3 of the partition entry.
+                raise MountError("setting custom partition type is only " \
+                                 "imlemented for GPT partitions")
+
+            # Get the disk where the partition is located
+            d = self.disks[p['disk_name']]
+            d['numpart'] += 1
+            d['ptable_format'] = ptable_format
+
+            if d['numpart'] == 1:
+                if ptable_format == "msdos":
+                    overhead = MBR_OVERHEAD
+                else:
+                    overhead = GPT_OVERHEAD
+
+                # Skip one sector required for the partitioning scheme overhead
+                d['offset'] += overhead
+                # Steal few sectors from the first partition to offset for the
+                # partitioning overhead
+                p['size'] -= overhead
+
+            if p['align']:
+                # If not first partition and we do have alignment set we need
+                # to align the partition.
+                # FIXME: This leaves a empty spaces to the disk. To fill the
+                # gaps we could enlargea the previous partition?
+
+                # Calc how much the alignment is off.
+                align_sectors = d['offset'] % (p['align'] * 1024 / self.sector_size)
+                # We need to move forward to the next alignment point
+                align_sectors = (p['align'] * 1024 / self.sector_size) - align_sectors
+
+                msger.debug("Realignment for %s%s with %s sectors, original"
+                            " offset %s, target alignment is %sK." %
+                            (p['disk_name'], d['numpart'], align_sectors,
+                             d['offset'], p['align']))
+
+                # increase the offset so we actually start the partition on right alignment
+                d['offset'] += align_sectors
+
+            p['start'] = d['offset']
+            d['offset'] += p['size']
+
+            p['type'] = 'primary'
+            p['num'] = d['numpart']
+
+            if d['ptable_format'] == "msdos":
+                if d['numpart'] > 2:
+                    # Every logical partition requires an additional sector for
+                    # the EBR, so steal the last sector from the end of each
+                    # partition starting from the 3rd one for the EBR. This
+                    # will make sure the logical partitions are aligned
+                    # correctly.
+                    p['size'] -= 1
+
+                if d['numpart'] > 3:
+                    p['type'] = 'logical'
+                    p['num'] = d['numpart'] + 1
+
+            d['partitions'].append(n)
+            msger.debug("Assigned %s to %s%d, sectors range %d-%d size %d "
+                        "sectors (%d bytes)." \
+                            % (p['mountpoint'], p['disk_name'], p['num'],
+                               p['start'], p['start'] + p['size'] - 1,
+                               p['size'], p['size'] * self.sector_size))
+
+        # Once all the partitions have been layed out, we can calculate the
+        # minumim disk sizes.
+        for disk_name, d in self.disks.items():
+            d['min_size'] = d['offset']
+            if d['ptable_format'] == 'gpt':
+                # Account for the backup partition table at the end of the disk
+                d['min_size'] += GPT_OVERHEAD
+
+            d['min_size'] *= self.sector_size
+
+    def __run_parted(self, args):
+        """ Run parted with arguments specified in the 'args' list. """
+
+        args.insert(0, self.parted)
+        msger.debug(args)
+
+        rc, out = runner.runtool(args, catch = 3)
+        out = out.strip()
+        if out:
+            msger.debug('"parted" output: %s' % out)
+
+        if rc != 0:
+            # We don't throw exception when return code is not 0, because
+            # parted always fails to reload part table with loop devices. This
+            # prevents us from distinguishing real errors based on return
+            # code.
+            msger.debug("WARNING: parted returned '%s' instead of 0" % rc)
+
+    def __create_partition(self, device, parttype, fstype, start, size):
+        """ Create a partition on an image described by the 'device' object. """
+
+        # Start is included to the size so we need to substract one from the end.
+        end = start + size - 1
+        msger.debug("Added '%s' partition, sectors %d-%d, size %d sectors" %
+                    (parttype, start, end, size))
+
+        args = ["-s", device, "unit", "s", "mkpart", parttype]
+        if fstype:
+            args.extend([fstype])
+        args.extend(["%d" % start, "%d" % end])
+
+        return self.__run_parted(args)
+
+    def __format_disks(self):
+        self.layout_partitions()
+
+        if self.skipformat:
+            msger.debug("Skipping disk format, because skipformat flag is set.")
+            return
+
+        for dev in self.disks.keys():
+            d = self.disks[dev]
+            msger.debug("Initializing partition table for %s" % \
+                        (d['disk'].device))
+            self.__run_parted(["-s", d['disk'].device, "mklabel",
+                               d['ptable_format']])
+
+        msger.debug("Creating partitions")
+
+        for p in self.partitions:
+            d = self.disks[p['disk_name']]
+            if d['ptable_format'] == "msdos" and p['num'] == 5:
+                # The last sector of the 3rd partition was reserved for the EBR
+                # of the first _logical_ partition. This is why the extended
+                # partition should start one sector before the first logical
+                # partition.
+                self.__create_partition(d['disk'].device, "extended",
+                                        None, p['start'] - 1,
+                                        d['offset'] - p['start'])
+
+            if p['fstype'] == "swap":
+                parted_fs_type = "linux-swap"
+            elif p['fstype'] == "vfat":
+                parted_fs_type = "fat32"
+            elif p['fstype'] == "msdos":
+                parted_fs_type = "fat16"
+            else:
+                # Type for ext2/ext3/ext4/btrfs
+                parted_fs_type = "ext2"
+
+            # Boot ROM of OMAP boards require vfat boot partition to have an
+            # even number of sectors.
+            if p['mountpoint'] == "/boot" and p['fstype'] in ["vfat", "msdos"] \
+               and p['size'] % 2:
+                msger.debug("Substracting one sector from '%s' partition to " \
+                            "get even number of sectors for the partition" % \
+                            p['mountpoint'])
+                p['size'] -= 1
+
+            self.__create_partition(d['disk'].device, p['type'],
+                                    parted_fs_type, p['start'], p['size'])
+
+            if p['boot']:
+                if d['ptable_format'] == 'gpt':
+                    flag_name = "legacy_boot"
+                else:
+                    flag_name = "boot"
+                msger.debug("Set '%s' flag for partition '%s' on disk '%s'" % \
+                            (flag_name, p['num'], d['disk'].device))
+                self.__run_parted(["-s", d['disk'].device, "set",
+                                   "%d" % p['num'], flag_name, "on"])
+
+            # Parted defaults to enabling the lba flag for fat16 partitions,
+            # which causes compatibility issues with some firmware (and really
+            # isn't necessary).
+            if parted_fs_type == "fat16":
+                if d['ptable_format'] == 'msdos':
+                    msger.debug("Disable 'lba' flag for partition '%s' on disk '%s'" % \
+                                (p['num'], d['disk'].device))
+                    self.__run_parted(["-s", d['disk'].device, "set",
+                                       "%d" % p['num'], "lba", "off"])
+
+        # If the partition table format is "gpt", find out PARTUUIDs for all
+        # the partitions. And if users specified custom parition type UUIDs,
+        # set them.
+        for disk_name, disk in self.disks.items():
+            if disk['ptable_format'] != 'gpt':
+                continue
+
+            pnum = 0
+            gpt_parser = GptParser(d['disk'].device, SECTOR_SIZE)
+            # Iterate over all GPT partitions on this disk
+            for entry in gpt_parser.get_partitions():
+                pnum += 1
+                # Find the matching partition in the 'self.partitions' list
+                for n in d['partitions']:
+                    p = self.partitions[n]
+                    if p['num'] == pnum:
+                        # Found, fetch PARTUUID (partition's unique ID)
+                        p['partuuid'] = entry['part_uuid']
+                        msger.debug("PARTUUID for partition %d on disk '%s' " \
+                                    "(mount point '%s') is '%s'" % (pnum, \
+                                    disk_name, p['mountpoint'], p['partuuid']))
+                        if p['part_type']:
+                            entry['type_uuid'] = p['part_type']
+                            msger.debug("Change type of partition %d on disk " \
+                                        "'%s' (mount point '%s') to '%s'" % \
+                                        (pnum, disk_name, p['mountpoint'],
+                                         p['part_type']))
+                            gpt_parser.change_partition(entry)
+
+            del gpt_parser
+
+    def __map_partitions(self):
+        """Load it if dm_snapshot isn't loaded. """
+        load_module("dm_snapshot")
+
+        for dev in self.disks.keys():
+            d = self.disks[dev]
+            if d['mapped']:
+                continue
+
+            msger.debug("Running kpartx on %s" % d['disk'].device )
+            rc, kpartxOutput = runner.runtool([self.kpartx, "-l", "-v", d['disk'].device])
+            kpartxOutput = kpartxOutput.splitlines()
+
+            if rc != 0:
+                raise MountError("Failed to query partition mapping for '%s'" %
+                                 d['disk'].device)
+
+            # Strip trailing blank and mask verbose output
+            i = 0
+            while i < len(kpartxOutput) and kpartxOutput[i][0:4] != "loop":
+                i = i + 1
+            kpartxOutput = kpartxOutput[i:]
+
+            # Make sure kpartx reported the right count of partitions
+            if len(kpartxOutput) != d['numpart']:
+                # If this disk has more than 3 partitions, then in case of MBR
+                # paritions there is an extended parition. Different versions
+                # of kpartx behave differently WRT the extended partition -
+                # some map it, some ignore it. This is why we do the below hack
+                # - if kpartx reported one more partition and the partition
+                # table type is "msdos" and the amount of partitions is more
+                # than 3, we just assume kpartx mapped the extended parition
+                # and we remove it.
+                if len(kpartxOutput) == d['numpart'] + 1 \
+                   and d['ptable_format'] == 'msdos' and len(kpartxOutput) > 3:
+                    kpartxOutput.pop(3)
+                else:
+                    raise MountError("Unexpected number of partitions from " \
+                                     "kpartx: %d != %d" % \
+                                        (len(kpartxOutput), d['numpart']))
+
+            for i in range(len(kpartxOutput)):
+                line = kpartxOutput[i]
+                newdev = line.split()[0]
+                mapperdev = "/dev/mapper/" + newdev
+                loopdev = d['disk'].device + newdev[-1]
+
+                msger.debug("Dev %s: %s -> %s" % (newdev, loopdev, mapperdev))
+                pnum = d['partitions'][i]
+                self.partitions[pnum]['device'] = loopdev
+
+                # grub's install wants partitions to be named
+                # to match their parent device + partition num
+                # kpartx doesn't work like this, so we add compat
+                # symlinks to point to /dev/mapper
+                if os.path.lexists(loopdev):
+                    os.unlink(loopdev)
+                os.symlink(mapperdev, loopdev)
+
+            msger.debug("Adding partx mapping for %s" % d['disk'].device)
+            rc = runner.show([self.kpartx, "-v", "-a", d['disk'].device])
+
+            if rc != 0:
+                # Make sure that the device maps are also removed on error case.
+                # The d['mapped'] isn't set to True if the kpartx fails so
+                # failed mapping will not be cleaned on cleanup either.
+                runner.quiet([self.kpartx, "-d", d['disk'].device])
+                raise MountError("Failed to map partitions for '%s'" %
+                                 d['disk'].device)
+
+            # FIXME: there is a bit delay for multipath device setup,
+            # wait 10ms for the setup
+            import time
+            time.sleep(10)
+            d['mapped'] = True
+
+    def __unmap_partitions(self):
+        for dev in self.disks.keys():
+            d = self.disks[dev]
+            if not d['mapped']:
+                continue
+
+            msger.debug("Removing compat symlinks")
+            for pnum in d['partitions']:
+                if self.partitions[pnum]['device'] != None:
+                    os.unlink(self.partitions[pnum]['device'])
+                    self.partitions[pnum]['device'] = None
+
+            msger.debug("Unmapping %s" % d['disk'].device)
+            rc = runner.quiet([self.kpartx, "-d", d['disk'].device])
+            if rc != 0:
+                raise MountError("Failed to unmap partitions for '%s'" %
+                                 d['disk'].device)
+
+            d['mapped'] = False
+
+    def __calculate_mountorder(self):
+        msger.debug("Calculating mount order")
+        for p in self.partitions:
+            if p['mountpoint']:
+                self.mountOrder.append(p['mountpoint'])
+                self.unmountOrder.append(p['mountpoint'])
+
+        self.mountOrder.sort()
+        self.unmountOrder.sort()
+        self.unmountOrder.reverse()
+
+    def cleanup(self):
+        Mount.cleanup(self)
+        if self.disks:
+            self.__unmap_partitions()
+            for dev in self.disks.keys():
+                d = self.disks[dev]
+                try:
+                    d['disk'].cleanup()
+                except:
+                    pass
+
+    def unmount(self):
+        self.__unmount_subvolumes()
+        for mp in self.unmountOrder:
+            if mp == 'swap':
+                continue
+            p = None
+            for p1 in self.partitions:
+                if p1['mountpoint'] == mp:
+                    p = p1
+                    break
+
+            if p['mount'] != None:
+                try:
+                    # Create subvolume snapshot here
+                    if p['fstype'] == "btrfs" and p['mountpoint'] == "/" and not self.snapshot_created:
+                        self.__create_subvolume_snapshots(p, p["mount"])
+                    p['mount'].cleanup()
+                except:
+                    pass
+                p['mount'] = None
+
+    # Only for btrfs
+    def __get_subvolume_id(self, rootpath, subvol):
+        if not self.btrfscmd:
+            self.btrfscmd=find_binary_path("btrfs")
+        argv = [ self.btrfscmd, "subvolume", "list", rootpath ]
+
+        rc, out = runner.runtool(argv)
+        msger.debug(out)
+
+        if rc != 0:
+            raise MountError("Failed to get subvolume id from %s', return code: %d." % (rootpath, rc))
+
+        subvolid = -1
+        for line in out.splitlines():
+            if line.endswith(" path %s" % subvol):
+                subvolid = line.split()[1]
+                if not subvolid.isdigit():
+                    raise MountError("Invalid subvolume id: %s" % subvolid)
+                subvolid = int(subvolid)
+                break
+        return subvolid
+
+    def __create_subvolume_metadata(self, p, pdisk):
+        if len(self.subvolumes) == 0:
+            return
+
+        argv = [ self.btrfscmd, "subvolume", "list", pdisk.mountdir ]
+        rc, out = runner.runtool(argv)
+        msger.debug(out)
+
+        if rc != 0:
+            raise MountError("Failed to get subvolume id from %s', return code: %d." % (pdisk.mountdir, rc))
+
+        subvolid_items = out.splitlines()
+        subvolume_metadata = ""
+        for subvol in self.subvolumes:
+            for line in subvolid_items:
+                if line.endswith(" path %s" % subvol["subvol"]):
+                    subvolid = line.split()[1]
+                    if not subvolid.isdigit():
+                        raise MountError("Invalid subvolume id: %s" % subvolid)
+
+                    subvolid = int(subvolid)
+                    opts = subvol["fsopts"].split(",")
+                    for opt in opts:
+                        if opt.strip().startswith("subvol="):
+                            opts.remove(opt)
+                            break
+                    fsopts = ",".join(opts)
+                    subvolume_metadata += "%d\t%s\t%s\t%s\n" % (subvolid, subvol["subvol"], subvol['mountpoint'], fsopts)
+
+        if subvolume_metadata:
+            fd = open("%s/.subvolume_metadata" % pdisk.mountdir, "w")
+            fd.write(subvolume_metadata)
+            fd.close()
+
+    def __get_subvolume_metadata(self, p, pdisk):
+        subvolume_metadata_file = "%s/.subvolume_metadata" % pdisk.mountdir
+        if not os.path.exists(subvolume_metadata_file):
+            return
+
+        fd = open(subvolume_metadata_file, "r")
+        content = fd.read()
+        fd.close()
+
+        for line in content.splitlines():
+            items = line.split("\t")
+            if items and len(items) == 4:
+                self.subvolumes.append({'size': 0, # In sectors
+                                        'mountpoint': items[2], # Mount relative to chroot
+                                        'fstype': "btrfs", # Filesystem type
+                                        'fsopts': items[3] + ",subvol=%s" %  items[1], # Filesystem mount options
+                                        'disk_name': p['disk_name'], # physical disk name holding partition
+                                        'device': None, # kpartx device node for partition
+                                        'mount': None, # Mount object
+                                        'subvol': items[1], # Subvolume name
+                                        'boot': False, # Bootable flag
+                                        'mounted': False # Mount flag
+                                   })
+
+    def __create_subvolumes(self, p, pdisk):
+        """ Create all the subvolumes. """
+
+        for subvol in self.subvolumes:
+            argv = [ self.btrfscmd, "subvolume", "create", pdisk.mountdir + "/" + subvol["subvol"]]
+
+            rc = runner.show(argv)
+            if rc != 0:
+                raise MountError("Failed to create subvolume '%s', return code: %d." % (subvol["subvol"], rc))
+
+        # Set default subvolume, subvolume for "/" is default
+        subvol = None
+        for subvolume in self.subvolumes:
+            if subvolume["mountpoint"] == "/" and p['disk_name'] == subvolume['disk_name']:
+                subvol = subvolume
+                break
+
+        if subvol:
+            # Get default subvolume id
+            subvolid = self. __get_subvolume_id(pdisk.mountdir, subvol["subvol"])
+            # Set default subvolume
+            if subvolid != -1:
+                rc = runner.show([ self.btrfscmd, "subvolume", "set-default", "%d" % subvolid, pdisk.mountdir])
+                if rc != 0:
+                    raise MountError("Failed to set default subvolume id: %d', return code: %d." % (subvolid, rc))
+
+        self.__create_subvolume_metadata(p, pdisk)
+
+    def __mount_subvolumes(self, p, pdisk):
+        if self.skipformat:
+            # Get subvolume info
+            self.__get_subvolume_metadata(p, pdisk)
+            # Set default mount options
+            if len(self.subvolumes) != 0:
+                for subvol in self.subvolumes:
+                    if subvol["mountpoint"] == p["mountpoint"] == "/":
+                        opts = subvol["fsopts"].split(",")
+                        for opt in opts:
+                            if opt.strip().startswith("subvol="):
+                                opts.remove(opt)
+                                break
+                        pdisk.fsopts = ",".join(opts)
+                        break
+
+        if len(self.subvolumes) == 0:
+            # Return directly if no subvolumes
+            return
+
+        # Remount to make default subvolume mounted
+        rc = runner.show([self.umountcmd, pdisk.mountdir])
+        if rc != 0:
+            raise MountError("Failed to umount %s" % pdisk.mountdir)
+
+        rc = runner.show([self.mountcmd, "-o", pdisk.fsopts, pdisk.disk.device, pdisk.mountdir])
+        if rc != 0:
+            raise MountError("Failed to umount %s" % pdisk.mountdir)
+
+        for subvol in self.subvolumes:
+            if subvol["mountpoint"] == "/":
+                continue
+            subvolid = self. __get_subvolume_id(pdisk.mountdir, subvol["subvol"])
+            if subvolid == -1:
+                msger.debug("WARNING: invalid subvolume %s" % subvol["subvol"])
+                continue
+            # Replace subvolume name with subvolume ID
+            opts = subvol["fsopts"].split(",")
+            for opt in opts:
+                if opt.strip().startswith("subvol="):
+                    opts.remove(opt)
+                    break
+
+            opts.extend(["subvolrootid=0", "subvol=%s" % subvol["subvol"]])
+            fsopts = ",".join(opts)
+            subvol['fsopts'] = fsopts
+            mountpoint = self.mountdir + subvol['mountpoint']
+            makedirs(mountpoint)
+            rc = runner.show([self.mountcmd, "-o", fsopts, pdisk.disk.device, mountpoint])
+            if rc != 0:
+                raise MountError("Failed to mount subvolume %s to %s" % (subvol["subvol"], mountpoint))
+            subvol["mounted"] = True
+
+    def __unmount_subvolumes(self):
+        """ It may be called multiple times, so we need to chekc if it is still mounted. """
+        for subvol in self.subvolumes:
+            if subvol["mountpoint"] == "/":
+                continue
+            if not subvol["mounted"]:
+                continue
+            mountpoint = self.mountdir + subvol['mountpoint']
+            rc = runner.show([self.umountcmd, mountpoint])
+            if rc != 0:
+                raise MountError("Failed to unmount subvolume %s from %s" % (subvol["subvol"], mountpoint))
+            subvol["mounted"] = False
+
+    def __create_subvolume_snapshots(self, p, pdisk):
+        import time
+
+        if self.snapshot_created:
+            return
+
+        # Remount with subvolid=0
+        rc = runner.show([self.umountcmd, pdisk.mountdir])
+        if rc != 0:
+            raise MountError("Failed to umount %s" % pdisk.mountdir)
+        if pdisk.fsopts:
+            mountopts = pdisk.fsopts + ",subvolid=0"
+        else:
+            mountopts = "subvolid=0"
+        rc = runner.show([self.mountcmd, "-o", mountopts, pdisk.disk.device, pdisk.mountdir])
+        if rc != 0:
+            raise MountError("Failed to umount %s" % pdisk.mountdir)
+
+        # Create all the subvolume snapshots
+        snapshotts = time.strftime("%Y%m%d-%H%M")
+        for subvol in self.subvolumes:
+            subvolpath = pdisk.mountdir + "/" + subvol["subvol"]
+            snapshotpath = subvolpath + "_%s-1" % snapshotts
+            rc = runner.show([ self.btrfscmd, "subvolume", "snapshot", subvolpath, snapshotpath ])
+            if rc != 0:
+                raise MountError("Failed to create subvolume snapshot '%s' for '%s', return code: %d." % (snapshotpath, subvolpath, rc))
+
+        self.snapshot_created = True
+
+    def __install_partition(self, num, source_file, start, size):
+        """
+        Install source_file contents into a partition.
+        """
+        if not source_file: # nothing to install
+            return
+
+        # Start is included in the size so need to substract one from the end.
+        end = start + size - 1
+        msger.debug("Installed %s in partition %d, sectors %d-%d, size %d sectors" % (source_file, num, start, end, size))
+
+        dd_cmd = "dd if=%s of=%s bs=%d seek=%d count=%d conv=notrunc" % \
+            (source_file, self.image_file, self.sector_size, start, size)
+        rc, out = exec_cmd(dd_cmd)
+
+
+    def install(self, image_file):
+        msger.debug("Installing partitions")
+
+        self.image_file = image_file
+
+        for p in self.partitions:
+            d = self.disks[p['disk_name']]
+            if d['ptable_format'] == "msdos" and p['num'] == 5:
+                # The last sector of the 3rd partition was reserved for the EBR
+                # of the first _logical_ partition. This is why the extended
+                # partition should start one sector before the first logical
+                # partition.
+                self.__install_partition(p['num'], p['source_file'],
+                                         p['start'] - 1,
+                                         d['offset'] - p['start'])
+
+            self.__install_partition(p['num'], p['source_file'],
+                                     p['start'], p['size'])
+
+    def mount(self):
+        for dev in self.disks.keys():
+            d = self.disks[dev]
+            d['disk'].create()
+
+        self.__format_disks()
+
+        self.__calculate_mountorder()
+
+        return
+
+    def resparse(self, size = None):
+        # Can't re-sparse a disk image - too hard
+        pass