diff options
| -rw-r--r-- | ChangeLog | 1 | ||||
| -rw-r--r-- | cloudinit/config/cc_resizefs.py | 203 |
2 files changed, 135 insertions, 69 deletions
@@ -42,6 +42,7 @@ in config (LP: #1115833). - improve debian support in sysvinit scripts, package build scripts, and split sources.list template to be distro specific. + - support for resizing btrfs root filesystems [Blair Zajac] 0.7.1: - sysvinit: fix missing dependency in cloud-init job for RHEL 5.6 - config-drive: map hostname to local-hostname (LP: #1061964) diff --git a/cloudinit/config/cc_resizefs.py b/cloudinit/config/cc_resizefs.py index 70294eda..44b27933 100644 --- a/cloudinit/config/cc_resizefs.py +++ b/cloudinit/config/cc_resizefs.py @@ -27,41 +27,111 @@ from cloudinit import util frequency = PER_ALWAYS + +def _resize_btrfs(mount_point, devpth): # pylint: disable=W0613 + return ('btrfs', 'filesystem', 'resize', 'max', mount_point) + + +def _resize_ext(mount_point, devpth): # pylint: disable=W0613 + return ('resize2fs', devpth) + + +def _resize_xfs(mount_point, devpth): # pylint: disable=W0613 + return ('xfs_growfs', devpth) + +# Do not use a dictionary as these commands should be able to be used +# for multiple filesystem types if possible, e.g. one command for +# ext2, ext3 and ext4. RESIZE_FS_PREFIXES_CMDS = [ - ('ext', 'resize2fs'), - ('xfs', 'xfs_growfs'), + ('btrfs', _resize_btrfs), + ('ext', _resize_ext), + ('xfs', _resize_xfs), ] NOBLOCK = "noblock" -def nodeify_path(devpth, where, log): - try: - st_dev = os.stat(where).st_dev - dev = os.makedev(os.major(st_dev), os.minor(st_dev)) - os.mknod(devpth, 0400 | stat.S_IFBLK, dev) - return st_dev - except: - if util.is_container(): - log.debug("Inside container, ignoring mknod failure in resizefs") - return - log.warn("Failed to make device node to resize %s at %s", - where, devpth) - raise - +def get_mount_info(path, log): + # Use /proc/$$/mountinfo to find the device where path is mounted. + # This is done because with a btrfs filesystem using os.stat(path) + # does not return the ID of the device. + # + # Here, / has a device of 18 (decimal). + # + # $ stat / + # File: '/' + # Size: 234 Blocks: 0 IO Block: 4096 directory + # Device: 12h/18d Inode: 256 Links: 1 + # Access: (0755/drwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root) + # Access: 2013-01-13 07:31:04.358011255 +0000 + # Modify: 2013-01-13 18:48:25.930011255 +0000 + # Change: 2013-01-13 18:48:25.930011255 +0000 + # Birth: - + # + # Find where / is mounted: + # + # $ mount | grep ' / ' + # /dev/vda1 on / type btrfs (rw,subvol=@,compress=lzo) + # + # And the device ID for /dev/vda1 is not 18: + # + # $ ls -l /dev/vda1 + # brw-rw---- 1 root disk 253, 1 Jan 13 08:29 /dev/vda1 + # + # So use /proc/$$/mountinfo to find the device underlying the + # input path. + path_elements = [e for e in path.split('/') if e] + devpth = None + fs_type = None + match_mount_point = None + match_mount_point_elements = None + mountinfo_path = '/proc/%s/mountinfo' % os.getpid() + for line in util.load_file(mountinfo_path).splitlines(): + parts = line.split() + + mount_point = parts[4] + mount_point_elements = [e for e in mount_point.split('/') if e] + + # Ignore mounts deeper than the path in question. + if len(mount_point_elements) > len(path_elements): + continue + + # Ignore mounts where the common path is not the same. + l = min(len(mount_point_elements), len(path_elements)) + if mount_point_elements[0:l] != path_elements[0:l]: + continue + + # Ignore mount points higher than an already seen mount + # point. + if (match_mount_point_elements is not None and + len(match_mount_point_elements) > len(mount_point_elements)): + continue + + # Find the '-' which terminates a list of optional columns to + # find the filesystem type and the path to the device. See + # man 5 proc for the format of this file. + try: + i = parts.index('-') + except ValueError: + log.debug("Did not find column named '-' in %s", + mountinfo_path) + return None -def get_fs_type(st_dev, path, log): - try: - dev_entries = util.find_devs_with(tag='TYPE', oformat='value', - no_cache=True, path=path) - if not dev_entries: + # Get the path to the device. + try: + fs_type = parts[i + 1] + devpth = parts[i + 2] + except IndexError: + log.debug("Too few columns in %s after '-' column", mountinfo_path) return None - return dev_entries[0].strip() - except util.ProcessExecutionError: - util.logexc(log, ("Failed to get filesystem type" - " of maj=%s, min=%s for path %s"), - os.major(st_dev), os.minor(st_dev), path) - raise + + match_mount_point = mount_point + match_mount_point_elements = mount_point_elements + + if devpth and fs_type and match_mount_point: + return (devpth, fs_type, match_mount_point) + else: + return None def handle(name, cfg, _cloud, log, args): @@ -80,52 +150,47 @@ def handle(name, cfg, _cloud, log, args): # TODO(harlowja): allow what is to be resized to be configurable?? resize_what = "/" - with util.ExtendedTemporaryFile(prefix="cloudinit.resizefs.", - dir=resize_root_d, delete=True) as tfh: - devpth = tfh.name - - # Delete the file so that mknod will work - # but don't change the file handle to know that its - # removed so that when a later call that recreates - # occurs this temporary file will still benefit from - # auto deletion - tfh.unlink_now() - - st_dev = nodeify_path(devpth, resize_what, log) - fs_type = get_fs_type(st_dev, devpth, log) - if not fs_type: - log.warn("Could not determine filesystem type of %s", resize_what) - return - - resizer = None - fstype_lc = fs_type.lower() - for (pfix, root_cmd) in RESIZE_FS_PREFIXES_CMDS: - if fstype_lc.startswith(pfix): - resizer = root_cmd - break - - if not resizer: - log.warn("Not resizing unknown filesystem type %s for %s", - fs_type, resize_what) - return - - log.debug("Resizing %s (%s) using %s", resize_what, fs_type, resizer) - resize_cmd = [resizer, devpth] - - if resize_root == NOBLOCK: - # Fork to a child that will run - # the resize command - util.fork_cb(do_resize, resize_cmd, log) - # Don't delete the file now in the parent - tfh.delete = False - else: - do_resize(resize_cmd, log) + result = get_mount_info(resize_what, log) + if not result: + log.warn("Could not determine filesystem type of %s", resize_what) + return + + (devpth, fs_type, mount_point) = result + + # Ensure the path is a block device. + if not stat.S_ISBLK(os.stat(devpth).st_mode): + log.debug("The %s device which was found for mount point %s for %s " + "is not a block device" % (devpth, mount_point, resize_what)) + return + + resizer = None + fstype_lc = fs_type.lower() + for (pfix, root_cmd) in RESIZE_FS_PREFIXES_CMDS: + if fstype_lc.startswith(pfix): + resizer = root_cmd + break + + if not resizer: + log.warn("Not resizing unknown filesystem type %s for %s", + fs_type, resize_what) + return + + resize_cmd = resizer(resize_what, devpth) + log.debug("Resizing %s (%s) using %s", resize_what, fs_type, + ' '.join(resize_cmd)) + + if resize_root == NOBLOCK: + # Fork to a child that will run + # the resize command + util.fork_cb(do_resize, resize_cmd, log) + else: + do_resize(resize_cmd, log) action = 'Resized' if resize_root == NOBLOCK: action = 'Resizing (via forking)' - log.debug("%s root filesystem (type=%s, maj=%i, min=%i, val=%s)", - action, fs_type, os.major(st_dev), os.minor(st_dev), resize_root) + log.debug("%s root filesystem (type=%s, val=%s)", action, fs_type, + resize_root) def do_resize(resize_cmd, log): |