ceph/src/ceph-disk

#!/usr/bin/python

import argparse
import errno
import logging
import os
import os.path
import platform
import re
import subprocess
import stat
import sys
import tempfile
import uuid

CEPH_OSD_ONDISK_MAGIC = 'ceph osd volume v026'

JOURNAL_UUID =         '45b0969e-9b03-4f30-b4c6-b4b80ceff106'
DMCRYPT_JOURNAL_UUID = '45b0969e-9b03-4f30-b4c6-5ec00ceff106'
OSD_UUID =             '4fbd7e29-9d25-41b8-afd0-062c0ceff05d'
DMCRYPT_OSD_UUID =     '4fbd7e29-9d25-41b8-afd0-5ec00ceff05d'
TOBE_UUID =            '89c57f98-2fe5-4dc0-89c1-f3ad0ceff2be'
DMCRYPT_TOBE_UUID =    '89c57f98-2fe5-4dc0-89c1-5ec00ceff2be'

DEFAULT_FS_TYPE = 'xfs'

MOUNT_OPTIONS = dict(
    btrfs='noatime,user_subvol_rm_allowed',
    # user_xattr is default ever since linux 2.6.39 / 3.0, but we'll
    # delay a moment before removing it fully because we did have some
    # issues with ext4 before the xatts-in-leveldb work, and it seemed
    # that user_xattr helped
    ext4='noatime,user_xattr',
    xfs='noatime',
    )

MKFS_ARGS = dict(
    btrfs=[
        '-m', 'single',
        '-l', '32768',
        '-n', '32768',
        ],
    xfs=[
        # xfs insists on not overwriting previous fs; even if we wipe
        # partition table, we often recreate it exactly the same way,
        # so we'll see ghosts of filesystems past
        '-f',
        '-i', 'size=2048',
        ],
    )

INIT_SYSTEMS = [
    'upstart',
    'sysvinit',
    'systemd',
    'auto',
    ]


log_name = __name__
if log_name == '__main__':
    log_name = os.path.basename(sys.argv[0])
log = logging.getLogger(log_name)


###### exceptions ########

class Error(Exception):
    """
    Error
    """

    def __str__(self):
        doc = self.__doc__.strip()
        return ': '.join([doc] + [str(a) for a in self.args])

class MountError(Error):
    """
    Mounting filesystem failed
    """

class UnmountError(Error):
    """
    Unmounting filesystem failed
    """

class BadMagicError(Error):
    """
    Does not look like a Ceph OSD, or incompatible version
    """

class TruncatedLineError(Error):
    """
    Line is truncated
    """


class TooManyLinesError(Error):
    """
    Too many lines
    """

class FilesystemTypeError(Error):
    """
    Cannot discover filesystem type
    """


####### utils


def maybe_mkdir(*a, **kw):
    # remove any symlink, if it is there..
    if os.path.exists(*a) and stat.S_ISLNK(os.lstat(*a).st_mode):
        log.debug('Removing old symlink at %s', *a)
        os.unlink(*a)
    try:
        os.mkdir(*a, **kw)
    except OSError, e:
        if e.errno == errno.EEXIST:
            pass
        else:
            raise


def list_all_partitions():
    """
    Return a list of devices and partitions
    """
    ls = {}
    with file('/proc/partitions', 'rb') as f:
        for line in f.read().split('\n')[2:]:
            fields = re.split('\s+', line)
            if len(fields) < 5:
                continue
            name = fields[4]
            name = '/dev/' + name
            if "dm-" in name:
                if "/dev/dm" not in ls:
                    ls["/dev/dm"] = []
                ls["/dev/dm"].append(name)
            if name[-1].isdigit():
                base = name
                while base[-1].isdigit():
                    base = base[:-1]
                    ls[base].append(name)
            else:
                ls[name] = []
    return ls


def list_partitions(disk):
    """
    Return a list of partitions on the given device
    """
    disk = os.path.realpath(disk)
    assert not is_partition(disk)
    assert disk.startswith('/dev/')
    base = disk[5:]
    ls = []
    with file('/proc/partitions', 'rb') as f:
        for line in f.read().split('\n')[2:]:
            fields = re.split('\s+', line)
            if len(fields) < 5:
                continue
            (_, major, minor, blocks, name) = fields
            if name != base and name.startswith(base):
                ls.append('/dev/' + name)
    return ls


def is_partition(dev):
    """
    Check whether a given device is a partition or a full disk.
    """
    dev = os.path.realpath(dev)
    if not stat.S_ISBLK(os.lstat(dev).st_mode):
        raise Error('not a block device', dev)

    # if the device ends in a number, it is a partition (e.g., /dev/sda3)
    if dev[-1].isdigit():
        return True
    return False


def is_mounted(dev):
    """
    Check if the given device is mounted.
    """
    dev = os.path.realpath(dev)
    with file('/proc/mounts') as f:
        for line in f.read().split('\n'):
            d = line.split(' ')[0]
            if os.path.exists(d):
                d = os.path.realpath(d)
                if dev == d:
                    return True
    return False


def is_held(dev):
    """
    Check if a device is held by another device (e.g., a dm-crypt mapping)
    """
    assert os.path.exists(dev)
    dev = os.path.realpath(dev)
    base = dev[5:]
    disk = base
    while disk[-1].isdigit():
        disk = disk[:-1]
    directory = '/sys/block/{disk}/{base}/holders'.format(disk=disk, base=base)
    if not os.path.exists(directory):
        return []
    return os.listdir(directory)


def verify_not_in_use(dev):
    assert os.path.exists(dev)
    if is_partition(dev):
        if is_mounted(dev):
            raise Error('Device is mounted', dev)
        holders = is_held(dev)
        if holders:
            raise Error('Device is in use by a device-mapper mapping (dm-crypt?)' % dev, ','.join(holders))
    else:
        for p in list_partitions(dev):
            if is_mounted(p):
                raise Error('Device is mounted', p)
            holders = is_held(p)
            if holders:
                raise Error('Device %s is in use by a device-mapper mapping (dm-crypt?)' % p, ','.join(holders))


def must_be_one_line(line):
    if line[-1:] != '\n':
        raise TruncatedLineError(line)
    line = line[:-1]
    if '\n' in line:
        raise TooManyLinesError(line)
    return line


def read_one_line(parent, name):
    """
    Read a file whose sole contents are a single line.

    Strips the newline.

    :return: Contents of the line, or None if file did not exist.
    """
    path = os.path.join(parent, name)
    try:
        line = file(path, 'rb').read()
    except IOError as e:
        if e.errno == errno.ENOENT:
            return None
        else:
            raise

    try:
        line = must_be_one_line(line)
    except (TruncatedLineError, TooManyLinesError) as e:
        raise Error('File is corrupt: {path}: {msg}'.format(
                path=path,
                msg=e,
                ))
    return line


def write_one_line(parent, name, text):
    """
    Write a file whose sole contents are a single line.

    Adds a newline.
    """
    path = os.path.join(parent, name)
    tmp = '{path}.{pid}.tmp'.format(path=path, pid=os.getpid())
    with file(tmp, 'wb') as f:
        f.write(text + '\n')
        os.fsync(f.fileno())
    os.rename(tmp, path)


def check_osd_magic(path):
    """
    Check that this path has the Ceph OSD magic.

    :raises: BadMagicError if this does not look like a Ceph OSD data
    dir.
    """
    magic = read_one_line(path, 'magic')
    if magic is None:
        # probably not mkfs'ed yet
        raise BadMagicError(path)
    if magic != CEPH_OSD_ONDISK_MAGIC:
        raise BadMagicError(path)


def check_osd_id(osd_id):
    """
    Ensures osd id is numeric.
    """
    if not re.match(r'^[0-9]+$', osd_id):
        raise Error('osd id is not numeric')


def allocate_osd_id(
    cluster,
    fsid,
    keyring,
    ):
    log.debug('Allocating OSD id...')
    try:
        osd_id = _check_output(
            args=[
                '/usr/bin/ceph',
                '--cluster', cluster,
                '--name', 'client.bootstrap-osd',
                '--keyring', keyring,
                'osd', 'create', '--concise',
                fsid,
                ],
            )
    except subprocess.CalledProcessError as e:
        raise Error('ceph osd create failed', e)
    osd_id = must_be_one_line(osd_id)
    check_osd_id(osd_id)
    return osd_id


def get_osd_id(path):
    osd_id = read_one_line(path, 'whoami')
    if osd_id is not None:
        check_osd_id(osd_id)
    return osd_id


def _check_output(*args, **kwargs):
    process = subprocess.Popen(
        stdout=subprocess.PIPE,
        *args, **kwargs)
    out, _ = process.communicate()
    ret = process.wait()
    if ret:
        cmd = kwargs.get("args")
        if cmd is None:
            cmd = args[0]
        raise subprocess.CalledProcessError(ret, cmd, output=out)
    return out


def get_conf(cluster, variable):
    try:
        p = subprocess.Popen(
            args=[
                '/usr/bin/ceph-conf',
                '--cluster={cluster}'.format(
                    cluster=cluster,
                    ),
                '--name=osd.',
                '--lookup',
                variable,
                ],
            stdout=subprocess.PIPE,
            close_fds=True,
            )
    except OSError as e:
        raise Error('error executing ceph-conf', e)
    (out, _err) = p.communicate()
    ret = p.wait()
    if ret == 1:
        # config entry not found
        return None
    elif ret != 0:
        raise Error('getting variable from configuration failed')
    value = out.split('\n', 1)[0]
    # don't differentiate between "var=" and no var set
    if not value:
        return None
    return value


def get_conf_with_default(cluster, variable):
    """
    Get a config value that is known to the C++ code.

    This will fail if called on variables that are not defined in
    common config options.
    """
    try:
        out = _check_output(
            args=[
                'ceph-osd',
                '--cluster={cluster}'.format(
                    cluster=cluster,
                    ),
                '--show-config-value={variable}'.format(
                    variable=variable,
                    ),
                ],
            close_fds=True,
            )
    except subprocess.CalledProcessError as e:
        raise Error(
            'getting variable from configuration failed',
            e,
            )

    value = out.split('\n', 1)[0]
    return value


def get_fsid(cluster):
    fsid = get_conf(cluster=cluster, variable='fsid')
    if fsid is None:
        raise Error('getting cluster uuid from configuration failed')
    return fsid


def get_or_create_dmcrypt_key(
    uuid,
    key_dir,
    ):
    path = os.path.join(key_dir, uuid)

    # already have it?
    if os.path.exists(path):
        return path

    # make a new key
    try:
        if not os.path.exists(key_dir):
            os.makedirs(key_dir)
        with file('/dev/urandom', 'rb') as i:
            key = i.read(256)
            with file(path, 'wb') as f:
                f.write(key)
        return path
    except:
        raise Error('unable to read or create dm-crypt key', path)


def dmcrypt_map(
    rawdev,
    keypath,
    uuid,
    ):
    dev = '/dev/mapper/'+ uuid
    args = [
        'cryptsetup',
        '--key-file',
        keypath,
        '--key-size', '256',
        'create',
        uuid,
        rawdev,
        ]
    try:
        subprocess.check_call(args)
        return dev

    except subprocess.CalledProcessError as e:
        raise Error('unable to map device', rawdev)


def dmcrypt_unmap(
    uuid
    ):
    args = [
        'cryptsetup',
        'remove',
        uuid
    ]

    try:
        subprocess.check_call(args)

    except subprocess.CalledProcessError as e:
        raise Error('unable to unmap device', uuid)


def mount(
    dev,
    fstype,
    options,
    ):
    # pick best-of-breed mount options based on fs type
    if options is None:
        options = MOUNT_OPTIONS.get(fstype, '')

    # mount
    path = tempfile.mkdtemp(
        prefix='mnt.',
        dir='/var/lib/ceph/tmp',
        )
    try:
        log.debug('Mounting %s on %s with options %s', dev, path, options)
        subprocess.check_call(
            args=[
                'mount',
                '-o', options,
                '--',
                dev,
                path,
                ],
            )
    except subprocess.CalledProcessError as e:
        try:
            os.rmdir(path)
        except (OSError, IOError):
            pass
        raise MountError(e)

    return path


def unmount(
    path,
    ):
    try:
        log.debug('Unmounting %s', path)
        subprocess.check_call(
            args=[
                '/bin/umount',
                '--',
                path,
                ],
            )
    except subprocess.CalledProcessError as e:
        raise UnmountError(e)

    os.rmdir(path)


###########################################


def get_free_partition_index(dev):
    try:
        lines = _check_output(
            args=[
                'parted',
                '--machine',
                '--',
                dev,
                'print',
                ],
            )
    except subprocess.CalledProcessError as e:
        print 'cannot read partition index; assume it isn\'t present\n'
        return 1

    if not lines:
        raise Error('parted failed to output anything')
    lines = lines.splitlines(True)

    if lines[0] not in ['CHS;\n', 'CYL;\n', 'BYT;\n']:
        raise Error('weird parted units', lines[0])
    del lines[0]

    if not lines[0].startswith('/dev/'):
        raise Error('weird parted disk entry', lines[0])
    del lines[0]

    seen = set()
    for line in lines:
        idx, _ = line.split(':', 1)
        idx = int(idx)
        seen.add(idx)

    num = 1
    while num in seen:
        num += 1
    return num


def zap(dev):
    """
    Destroy the partition table and content of a given disk.
    """
    try:
        log.debug('Zapping partition table on %s', dev)

        # try to wipe out any GPT partition table backups.  sgdisk
        # isn't too thorough.
        lba_size = 4096
        size = 33 * lba_size
        with file(dev, 'wb') as f:
            f.seek(-size, os.SEEK_END)
            f.write(size*'\0')

        subprocess.check_call(
            args=[
                'sgdisk',
                '--zap-all',
                '--clear',
                '--mbrtogpt',
                '--',
                dev,
                ],
            )
    except subprocess.CalledProcessError as e:
        raise Error(e)


def prepare_journal_dev(
    data,
    journal,
    journal_size,
    journal_uuid,
    journal_dm_keypath,
    ):

    if is_partition(journal):
        log.debug('Journal %s is a partition', journal)
        log.warning('OSD will not be hot-swappable if journal is not the same device as the osd data')
        return (journal, None, None)

    key = None
    ptype = JOURNAL_UUID
    if journal_dm_keypath:
        ptype = DMCRYPT_JOURNAL_UUID

    # it is a whole disk.  create a partition!
    num = None
    if journal == data:
        # we're sharing the disk between osd data and journal;
        # make journal be partition number 2, so it's pretty; put
        # journal at end of free space so partitioning tools don't
        # reorder them suddenly
        num = 2
        journal_part = '{num}:-{size}M:0'.format(
            num=num,
            size=journal_size,
            )
    else:
        # sgdisk has no way for me to say "whatever is the next
        # free index number" when setting type guids etc, so we
        # need to awkwardly look up the next free number, and then
        # fix that in the call -- and hope nobody races with us;
        # then again nothing guards the partition table from races
        # anyway
        num = get_free_partition_index(dev=journal)
        journal_part = '{num}:0:+{size}M'.format(
            num=num,
            size=journal_size,
            )
        log.warning('OSD will not be hot-swappable if journal is not the same device as the osd data')

    try:
        log.debug('Creating journal partition num %d size %d on %s', num, journal_size, journal)
        subprocess.check_call(
            args=[
                'sgdisk',
                '--new={part}'.format(part=journal_part),
                '--change-name={num}:ceph journal'.format(num=num),
                '--partition-guid={num}:{journal_uuid}'.format(
                    num=num,
                    journal_uuid=journal_uuid,
                    ),
                '--typecode={num}:{uuid}'.format(
                    num=num,
                    uuid=ptype,
                    ),
                '--',
                journal,
                ],
            )
        subprocess.check_call(
            args=[
                # also make sure the kernel refreshes the new table
                'partprobe',
                journal,
                ],
            )

        journal_symlink = '/dev/disk/by-partuuid/{journal_uuid}'.format(
            journal_uuid=journal_uuid,
            )

        journal_dmcrypt = None
        if journal_dm_keypath:
            journal_dmcrypt = journal_symlink
            journal_symlink = '/dev/mapper/{uuid}'.format(uuid=journal_uuid)

        log.debug('Journal is GPT partition %s', journal_symlink)
        return (journal_symlink, journal_dmcrypt, journal_uuid)

    except subprocess.CalledProcessError as e:
        raise Error(e)


def prepare_journal_file(
    journal,
    journal_size):

    if not os.path.exists(journal):
        log.debug('Creating journal file %s with size %dM', journal, journal_size)
        with file(journal, 'wb') as f:
            f.truncate(journal_size * 1048576)

    # FIXME: should we resize an existing journal file?

    log.debug('Journal is file %s', journal)
    log.warning('OSD will not be hot-swappable if journal is not the same device as the osd data')
    return (journal, None, None)


def prepare_journal(
    data,
    journal,
    journal_size,
    journal_uuid,
    force_file,
    force_dev,
    journal_dm_keypath,
    ):

    if journal is None:
        if force_dev:
            raise Error('Journal is unspecified; not a block device')
        return (None, None, None)

    if not os.path.exists(journal):
        if force_dev:
            raise Error('Journal does not exist; not a block device', journal)
        return prepare_journal_file(journal, journal_size)

    jmode = os.stat(journal).st_mode
    if stat.S_ISREG(jmode):
        if force_dev:
            raise Error('Journal is not a block device', journal)
        return prepare_journal_file(journal, journal_size)

    if stat.S_ISBLK(jmode):
        if force_file:
            raise Error('Journal is not a regular file', journal)
        return prepare_journal_dev(data, journal, journal_size, journal_uuid, journal_dm_keypath)

    raise Error('Journal %s is neither a block device nor regular file', journal)


def adjust_symlink(target, path):
    create = True
    if os.path.lexists(path):
        try:
            mode = os.path.lstat(canonical).st_mode
            if stat.S_ISREG(mode):
                log.debug('Removing old file %s', canonical)
                os.unlink(canonical)
            elif stat.S_ISLNK(mode):
                old = os.readlink(canonical)
                if old != journal:
                    log.debug('Removing old symlink %s -> %s', canonical, old)
                    os.unlink(canonical)
                else:
                    create = False
        except:
            raise Error('unable to remove (or adjust) old file (symlink)', canonical)
    if create:
        log.debug('Creating symlink %s -> %s', path, target)
        try:
            os.symlink(target, path)
        except:
            raise Error('unable to create symlink %s -> %s' % (path, target))

def prepare_dir(
    path,
    journal,
    cluster_uuid,
    osd_uuid,
    journal_uuid,
    journal_dmcrypt = None,
    ):
    log.debug('Preparing osd data dir %s', path)

    if osd_uuid is None:
        osd_uuid = str(uuid.uuid4())

    if journal is not None:
        # we're using an external journal; point to it here
        adjust_symlink(journal, os.path.join(path, 'journal'))

    if journal_dmcrypt is not None:
        adjust_symlink(journal_dmcrypt, os.path.join(path, 'journal_dmcrypt'))
    else:
        try:
            os.unlink(os.path.join(path, 'journal_dmcrypt'))
        except:
            pass

    write_one_line(path, 'ceph_fsid', cluster_uuid)
    write_one_line(path, 'fsid', osd_uuid)
    write_one_line(path, 'magic', CEPH_OSD_ONDISK_MAGIC)

    if journal_uuid is not None:
        # i.e., journal is a tagged partition
        write_one_line(path, 'journal_uuid', journal_uuid)

def prepare_dev(
    data,
    journal,
    fstype,
    mkfs_args,
    mount_options,
    cluster_uuid,
    osd_uuid,
    journal_uuid,
    journal_dmcrypt,
    osd_dm_keypath,
    ):
    """
    Prepare a data/journal combination to be used for an OSD.

    The ``magic`` file is written last, so it's presence is a reliable
    indicator of the whole sequence having completed.

    WARNING: This will unconditionally overwrite anything given to
    it.
    """

    ptype_tobe = TOBE_UUID
    ptype_osd = OSD_UUID
    if osd_dm_keypath:
        ptype_tobe = DMCRYPT_TOBE_UUID
        ptype_osd = DMCRYPT_OSD_UUID

    rawdev = None
    if is_partition(data):
        log.debug('OSD data device %s is a partition', data)
        rawdev = data
    else:
        log.debug('Creating osd partition on %s', data)
        try:
            subprocess.check_call(
                args=[
                    'sgdisk',
                    '--largest-new=1',
                    '--change-name=1:ceph data',
                    '--partition-guid=1:{osd_uuid}'.format(
                        osd_uuid=osd_uuid,
                        ),
                    '--typecode=1:%s' % ptype_tobe,
                    '--',
                    data,
                    ],
                )
            subprocess.check_call(
                args=[
                    # also make sure the kernel refreshes the new table
                    'partprobe',
                    data,
                    ],
                )
        except subprocess.CalledProcessError as e:
            raise Error(e)

        rawdev = '{data}1'.format(data=data)

    dev = None
    if osd_dm_keypath:
        dev = dmcrypt_map(rawdev, osd_dm_keypath, osd_uuid)
    else:
        dev = rawdev

    try:
        args = [
            'mkfs',
            '-t',
            fstype,
            ]
        if mkfs_args is not None:
            args.extend(mkfs_args.split())
            if fstype == 'xfs':
                args.extend(['-f'])  # always force
        else:
            args.extend(MKFS_ARGS.get(fstype, []))
        args.extend([
                '--',
                dev,
                ])
        try:
            log.debug('Creating %s fs on %s', fstype, dev)
            subprocess.check_call(args=args)
        except subprocess.CalledProcessError as e:
            raise Error(e)

        #remove whitespaces from mount_options
        if mount_options is not None:
            mount_options = "".join(mount_options.split())

        path = mount(dev=dev, fstype=fstype, options=mount_options)

        try:
            prepare_dir(
                path=path,
                journal=journal,
                cluster_uuid=cluster_uuid,
                osd_uuid=osd_uuid,
                journal_uuid=journal_uuid,
                journal_dmcrypt=journal_dmcrypt,
                )
        finally:
            unmount(path)
    finally:
        if rawdev != dev:
            dmcrypt_unmap(osd_uuid)

    if not is_partition(data):
        try:
            subprocess.check_call(
                args=[
                    'sgdisk',
                    '--typecode=1:%s' % ptype_osd,
                    '--',
                    data,
                    ],
                )
            subprocess.check_call(
                args=[
                    # also make sure the kernel refreshes the new table
                    'partprobe',
                    data,
                    ],
                )
        except subprocess.CalledProcessError as e:
            raise Error(e)


def main_prepare(args):
    journal_dm_keypath = None
    osd_dm_keypath = None

    try:
        if not os.path.exists(args.data):
            raise Error('data path does not exist', args.data)

        # in use?
        dmode = os.stat(args.data).st_mode
        if stat.S_ISBLK(dmode):
            verify_not_in_use(args.data)

        if args.journal and os.path.exists(args.journal):
            jmode = os.stat(args.journal).st_mode
            if stat.S_ISBLK(jmode):
                verify_not_in_use(args.journal)

        if args.zap_disk is not None:
            if stat.S_ISBLK(dmode) and not is_partition(args.data):
                zap(args.data)
            else:
                raise Error('not full block device; cannot zap', args.data)

        if args.cluster_uuid is None:
            args.cluster_uuid = get_fsid(cluster=args.cluster)
            if args.cluster_uuid is None:
                raise Error(
                    'must have fsid in config or pass --cluster--uuid=',
                    )

        if args.fs_type is None:
            args.fs_type = get_conf(
                cluster=args.cluster,
                variable='osd_mkfs_type',
                )
            if args.fs_type is None:
                args.fs_type = get_conf(
                    cluster=args.cluster,
                    variable='osd_fs_type',
                    )
            if args.fs_type is None:
                args.fs_type = DEFAULT_FS_TYPE

        mkfs_args = get_conf(
            cluster=args.cluster,
            variable='osd_mkfs_options_{fstype}'.format(
                fstype=args.fs_type,
                ),
            )
        if mkfs_args is None:
            mkfs_args = get_conf(
                cluster=args.cluster,
                variable='osd_fs_mkfs_options_{fstype}'.format(
                    fstype=args.fs_type,
                    ),
                )

        mount_options = get_conf(
            cluster=args.cluster,
            variable='osd_mount_options_{fstype}'.format(
                fstype=args.fs_type,
                ),
            )
        if mount_options is None:
            mount_options = get_conf(
                cluster=args.cluster,
                variable='osd_fs_mount_options_{fstype}'.format(
                    fstype=args.fs_type,
                    ),
                )

        journal_size = get_conf_with_default(
            cluster=args.cluster,
            variable='osd_journal_size',
            )
        journal_size = int(journal_size)

        # colocate journal with data?
        if stat.S_ISBLK(dmode) and not is_partition(args.data) and args.journal is None and args.journal_file is None:
            log.info('Will colocate journal with data on %s', args.data)
            args.journal = args.data

        if args.journal_uuid is None:
            args.journal_uuid = str(uuid.uuid4())
        if args.osd_uuid is None:
            args.osd_uuid = str(uuid.uuid4())

        # dm-crypt keys?
        if args.dmcrypt:
            journal_dm_keypath = get_or_create_dmcrypt_key(args.journal_uuid, args.dmcrypt_key_dir)
            osd_dm_keypath = get_or_create_dmcrypt_key(args.osd_uuid, args.dmcrypt_key_dir)

        # prepare journal
        (journal_symlink, journal_dmcrypt, journal_uuid) = prepare_journal(
            data=args.data,
            journal=args.journal,
            journal_size=journal_size,
            journal_uuid=args.journal_uuid,
            force_file=args.journal_file,
            force_dev=args.journal_dev,
            journal_dm_keypath=journal_dm_keypath,
            )

        # prepare data
        if stat.S_ISDIR(dmode):
            if args.data_dev:
                raise Error('data path is not a block device', args.data)
            prepare_dir(
                path=args.data,
                journal=journal_symlink,
                cluster_uuid=args.cluster_uuid,
                osd_uuid=args.osd_uuid,
                journal_uuid=journal_uuid,
                journal_dmcrypt=journal_dmcrypt,
                )
        elif stat.S_ISBLK(dmode):
            if args.data_dir:
                raise Error('data path is not a directory', args.data)
            prepare_dev(
                data=args.data,
                journal=journal_symlink,
                fstype=args.fs_type,
                mkfs_args=mkfs_args,
                mount_options=mount_options,
                cluster_uuid=args.cluster_uuid,
                osd_uuid=args.osd_uuid,
                journal_uuid=journal_uuid,
                journal_dmcrypt=journal_dmcrypt,
                osd_dm_keypath=osd_dm_keypath,
                )
        else:
            raise Error('not a dir or block device', args.data)

    except Error as e:
        if journal_dm_keypath:
            os.unlink(journal_dm_keypath)
        if osd_dm_keypath:
            os.unlink(osd_dm_keypath)
        raise e


###########################


def mkfs(
    path,
    cluster,
    osd_id,
    fsid,
    keyring,
    ):
    monmap = os.path.join(path, 'activate.monmap')
    subprocess.check_call(
        args=[
            '/usr/bin/ceph',
            '--cluster', cluster,
            '--name', 'client.bootstrap-osd',
            '--keyring', keyring,
            'mon', 'getmap', '-o', monmap,
            ],
        )

    subprocess.check_call(
        args=[
            '/usr/bin/ceph-osd',
            '--cluster', cluster,
            '--mkfs',
            '--mkkey',
            '-i', osd_id,
            '--monmap', monmap,
            '--osd-data', path,
            '--osd-journal', os.path.join(path, 'journal'),
            '--osd-uuid', fsid,
            '--keyring', os.path.join(path, 'keyring'),
            ],
        )
    # TODO ceph-osd --mkfs removes the monmap file?
    # os.unlink(monmap)


def auth_key(
    path,
    cluster,
    osd_id,
    keyring,
    ):
    subprocess.check_call(
        args=[
            '/usr/bin/ceph',
            '--cluster', cluster,
            '--name', 'client.bootstrap-osd',
            '--keyring', keyring,
            'auth', 'add', 'osd.{osd_id}'.format(osd_id=osd_id),
            '-i', os.path.join(path, 'keyring'),
            'osd', 'allow *',
            'mon', 'allow rwx',
            ],
        )


def move_mount(
    path,
    cluster,
    osd_id,
    ):
    log.debug('Moving mount to final location...')
    parent = '/var/lib/ceph/osd'
    osd_data = os.path.join(
        parent,
        '{cluster}-{osd_id}'.format(cluster=cluster, osd_id=osd_id),
        )
    maybe_mkdir(osd_data)
    subprocess.check_call(
        args=[
            '/bin/mount',
            '--move',
            '--',
            path,
            osd_data,
            ],
        )


def start_daemon(
    cluster,
    osd_id,
    ):
    log.debug('Starting %s osd.%s...', cluster, osd_id)

    path = '/var/lib/ceph/osd/{cluster}-{osd_id}'.format(
        cluster=cluster, osd_id=osd_id)

    # upstart?
    try:
        if os.path.exists(os.path.join(path,'upstart')):
            subprocess.check_call(
                args=[
                    '/sbin/initctl',
                    # use emit, not start, because start would fail if the
                    # instance was already running
                    'emit',
                    # since the daemon starting doesn't guarantee much about
                    # the service being operational anyway, don't bother
                    # waiting for it
                    '--no-wait',
                    '--',
                    'ceph-osd',
                    'cluster={cluster}'.format(cluster=cluster),
                    'id={osd_id}'.format(osd_id=osd_id),
                    ],
                )
        elif os.path.exists(os.path.join(path, 'sysvinit')):
            subprocess.check_call(
                args=[
                    '/usr/sbin/service',
                    'ceph',
                    'start',
                    'osd.{osd_id}'.format(osd_id=osd_id),
                    ],
                )
        else:
            raise Error('{cluster} osd.{osd_id} is not tagged with an init system'.format(
                    cluster=cluster,
                    osd_id=osd_id,
                    ))
    except subprocess.CalledProcessError as e:
        raise Error('ceph osd start failed', e)

def detect_fstype(
    dev,
    ):
    fstype = _check_output(
        args=[
            '/sbin/blkid',
            # we don't want stale cached results
            '-p',
            '-s', 'TYPE',
            '-o' 'value',
            '--',
            dev,
            ],
        )
    fstype = must_be_one_line(fstype)
    return fstype


def mount_activate(
    dev,
    activate_key_template,
    init,
    ):

    try:
        fstype = detect_fstype(dev=dev)
    except (subprocess.CalledProcessError,
            TruncatedLineError,
            TooManyLinesError) as e:
        raise FilesystemTypeError(
            'device {dev}'.format(dev=dev),
            e,
            )

    # TODO always using mount options from cluster=ceph for
    # now; see http://tracker.newdream.net/issues/3253
    mount_options = get_conf(
        cluster='ceph',
        variable='osd_mount_options_{fstype}'.format(
            fstype=fstype,
            ),
        )

    if mount_options is None:
        mount_options = get_conf(
            cluster='ceph',
            variable='osd_fs_mount_options_{fstype}'.format(
                fstype=fstype,
                ),
            )

    #remove whitespaces from mount_options
    if mount_options is not None:
        mount_options = "".join(mount_options.split())

    path = mount(dev=dev, fstype=fstype, options=mount_options)

    osd_id = None
    cluster = None
    try:
        (osd_id, cluster) = activate(path, activate_key_template, init)

        # check if the disk is already active, or if something else is already
        # mounted there
        active = False
        other = False
        src_dev = os.stat(path).st_dev
        try:
            dst_dev = os.stat('/var/lib/ceph/osd/{cluster}-{osd_id}'.format(
                    cluster=cluster,
                    osd_id=osd_id)).st_dev
            if src_dev == dst_dev:
                active = True
            else:
                parent_dev = os.stat('/var/lib/ceph/osd').st_dev
                if dst_dev != parent_dev:
                    other = True
        except:
            pass
        if active:
            log.info('%s osd.%s already mounted in position; unmounting ours.' % (cluster, osd_id))
            unmount(path)
        elif other:
            raise Error('another %s osd.%s already mounted in position (old/different cluster instance?); unmounting ours.' % (cluster, osd_id))
        else:
            move_mount(
                path=path,
                cluster=cluster,
                osd_id=osd_id,
                )
        return (cluster, osd_id)

    except:
        log.error('Failed to activate')
        unmount(path)
        raise
    finally:
        # remove out temp dir
        os.rmdir(path)


def activate_dir(
    path,
    activate_key_template,
    init,
    ):

    if not os.path.exists(path):
        raise Error(
            'directory %s does not exist' % path
            )

    (osd_id, cluster) = activate(path, activate_key_template, init)
    canonical = '/var/lib/ceph/osd/{cluster}-{osd_id}'.format(
        cluster=cluster,
        osd_id=osd_id)
    if path != canonical:
        # symlink it from the proper location
        create = True
        if os.path.lexists(canonical):
            old = os.readlink(canonical)
            if old != path:
                log.debug('Removing old symlink %s -> %s', canonical, old)
                try:
                    os.unlink(canonical)
                except:
                    raise Error('unable to remove old symlink %s', canonical)
            else:
                create = False
        if create:
            log.debug('Creating symlink %s -> %s', canonical, path)
            try:
                os.symlink(path, canonical)
            except:
                raise Error('unable to create symlink %s -> %s', canonical, path)

    return (cluster, osd_id)


def find_cluster_by_uuid(uuid):
    """
    Find a cluster name by searching /etc/ceph/*.conf for a conf file
    with the right uuid.
    """
    no_fsid = []
    if not os.path.exists('/etc/ceph'):
        return None
    for conf_file in os.listdir('/etc/ceph'):
        if not conf_file.endswith('.conf'):
            continue
        cluster = conf_file[:-5]
        u = get_conf(cluster, 'fsid')
        if u is None:
            no_fsid.append(cluster)
        elif u == uuid:
            return cluster
    # be tolerant of /etc/ceph/ceph.conf without an fsid defined.
    if len(no_fsid) == 1 and no_fsid[0] == 'ceph':
        log.warning('No fsid defined in /etc/ceph/ceph.conf; using anyway')
        return 'ceph'
    return None

def activate(
    path,
    activate_key_template,
    init,
    ):

    try:
        check_osd_magic(path)

        ceph_fsid = read_one_line(path, 'ceph_fsid')
        if ceph_fsid is None:
            raise Error('No cluster uuid assigned.')
        log.debug('Cluster uuid is %s', ceph_fsid)

        cluster = find_cluster_by_uuid(ceph_fsid)
        if cluster is None:
            raise Error('No cluster conf found in /etc/ceph with fsid %s' % ceph_fsid)
        log.debug('Cluster name is %s', cluster)

        fsid = read_one_line(path, 'fsid')
        if fsid is None:
            raise Error('No OSD uuid assigned.')
        log.debug('OSD uuid is %s', fsid)

        keyring = activate_key_template.format(cluster=cluster)

        osd_id = get_osd_id(path)
        if osd_id is None:
            osd_id = allocate_osd_id(
                cluster=cluster,
                fsid=fsid,
                keyring=keyring,
                )
            write_one_line(path, 'whoami', osd_id)
        log.debug('OSD id is %s', osd_id)

        if not os.path.exists(os.path.join(path, 'ready')):
            log.debug('Initializing OSD...')
            # re-running mkfs is safe, so just run until it completes
            mkfs(
                path=path,
                cluster=cluster,
                osd_id=osd_id,
                fsid=fsid,
                keyring=keyring,
                )

        if init is not None:
            if init == 'auto':
                c = get_conf(
                    cluster=cluster,
                    variable='init'
                    )
                if c is not None:
                    init = c
                else:
                    (distro, release, codename) = platform.dist()
                    if distro == 'Ubuntu':
                        init = 'upstart'
                    else:
                        init = 'sysvinit'

            log.debug('Marking with init system %s', init)
            with file(os.path.join(path, init), 'w'):
                pass

            # remove markers for others, just in case.
            for other in INIT_SYSTEMS:
                if other != init:
                    try:
                        os.unlink(os.path.join(path, other))
                    except:
                        pass

        if not os.path.exists(os.path.join(path, 'active')):
            log.debug('Authorizing OSD key...')
            auth_key(
                path=path,
                cluster=cluster,
                osd_id=osd_id,
                keyring=keyring,
                )
            write_one_line(path, 'active', 'ok')
        log.debug('%s osd.%s data dir is ready at %s', cluster, osd_id, path)
        return (osd_id, cluster)
    except:
        raise



def main_activate(args):
    cluster = None
    osd_id = None

    if not os.path.exists(args.path):
        raise Error('%s does not exist', args.path)

    mode = os.stat(args.path).st_mode
    if stat.S_ISBLK(mode):
        (cluster, osd_id) = mount_activate(
            dev=args.path,
            activate_key_template=args.activate_key_template,
            init=args.mark_init,
            )
    elif stat.S_ISDIR(mode):
        (cluster, osd_id) = activate_dir(
            path=args.path,
            activate_key_template=args.activate_key_template,
            init=args.mark_init,
            )
    else:
        raise Error('%s is not a directory or block device', args.path)

    start_daemon(
        cluster=cluster,
        osd_id=osd_id,
        )



###########################


def list_dev(dev):
    print '%s' % dev
    
def main_list(args):
    ls = list_all_partitions()
    log.debug('partitions are %s' % ls)

    for base, parts in ls.iteritems():
        if parts:
            print '%s :' % base
            for part in parts:
                list_dev(part)
        else:
            list_dev(base)


###########################


def parse_args():
    parser = argparse.ArgumentParser(
        'ceph-disk',
        )
    parser.add_argument(
        '-v', '--verbose',
        action='store_true', default=None,
        help='be more verbose',
        )
    parser.set_defaults(
        # we want to hold on to this, for later
        prog=parser.prog,
        cluster='ceph',
        )

    subparsers = parser.add_subparsers(
        title='subcommands',
        description='valid subcommands',
        help='sub-command help',
        )

    prepare_parser = subparsers.add_parser('prepare', help='Prepare a directory or disk for a Ceph OSD')
    prepare_parser.add_argument(
        '--cluster',
        metavar='NAME',
        help='cluster name to assign this disk to',
        )
    prepare_parser.add_argument(
        '--cluster-uuid',
        metavar='UUID',
        help='cluster uuid to assign this disk to',
        )
    prepare_parser.add_argument(
        '--osd-uuid',
        metavar='UUID',
        help='unique OSD uuid to assign this disk to',
        )
    prepare_parser.add_argument(
        '--journal-uuid',
        metavar='UUID',
        help='unique uuid to assign to the journal',
        )
    prepare_parser.add_argument(
        '--fs-type',
        help='file system type to use (e.g. "ext4")',
        )
    prepare_parser.add_argument(
        '--zap-disk',
        action='store_true', default=None,
        help='destroy the partition table (and content) of a disk',
        )
    prepare_parser.add_argument(
        '--data-dir',
        action='store_true', default=None,
        help='verify that DATA is a dir',
        )
    prepare_parser.add_argument(
        '--data-dev',
        action='store_true', default=None,
        help='verify that DATA is a block device',
        )
    prepare_parser.add_argument(
        '--journal-file',
        action='store_true', default=None,
        help='verify that JOURNAL is a file',
        )
    prepare_parser.add_argument(
        '--journal-dev',
        action='store_true', default=None,
        help='verify that JOURNAL is a block device',
        )
    prepare_parser.add_argument(
        '--dmcrypt',
        action='store_true', default=None,
        help='encrypt DATA and/or JOURNAL devices with dm-crypt',
        )
    prepare_parser.add_argument(
        '--dmcrypt-key-dir',
        metavar='KEYDIR',
        default='/etc/ceph/dmcrypt-keys',
        help='directory where dm-crypt keys are stored',
        )
    prepare_parser.add_argument(
        'data',
        metavar='DATA',
        help='path to OSD data (a disk block device or directory)',
        )
    prepare_parser.add_argument(
        'journal',
        metavar='JOURNAL',
        nargs='?',
        help=('path to OSD journal disk block device;'
              + ' leave out to store journal in file'),
        )
    prepare_parser.set_defaults(
        func=main_prepare,
        )

    activate_parser = subparsers.add_parser('activate', help='Activate a Ceph OSD')
    activate_parser.add_argument(
        '--mount',
        action='store_true', default=None,
        help='mount a block device [deprecated, ignored]',
        )
    activate_parser.add_argument(
        '--activate-key',
        metavar='PATH',
        help='bootstrap-osd keyring path template (%(default)s)',
        dest='activate_key_template',
        )
    activate_parser.add_argument(
        '--mark-init',
        metavar='INITSYSTEM',
        help='init system to manage this dir',
        default='auto',
        choices=INIT_SYSTEMS,
        )
    activate_parser.add_argument(
        'path',
        metavar='PATH',
        nargs='?',
        help='path to block device or directory',
        )
    activate_parser.set_defaults(
        activate_key_template='/var/lib/ceph/bootstrap-osd/{cluster}.keyring',
        func=main_activate,
        )

    list_parser = subparsers.add_parser('list', help='List disks, partitions, and Ceph OSDs')
    list_parser.set_defaults(
        func=main_list,
        )

    args = parser.parse_args()
    return args


def main():
    args = parse_args()

    loglevel = logging.INFO
    if args.verbose:
        loglevel = logging.DEBUG

    logging.basicConfig(
        level=loglevel,
        )

    try:
        args.func(args)

    except Error as e:
        print >>sys.stderr, '{prog}: {msg}'.format(
            prog=args.prog,
            msg=e,
            )
        sys.exit(1)


if __name__ == '__main__':
    main()