merge from trunk at revno 799

1 files changed, 272 insertions, 0 deletions

diff --git a/cloudinit/config/cc_growpart.py b/cloudinit/config/cc_growpart.py
new file mode 100644
index 00000000..b6e1fd37
--- /dev/null
+++ b/cloudinit/config/cc_growpart.py
@@ -0,0 +1,272 @@
+# vi: ts=4 expandtab
+#
+#    Copyright (C) 2011 Canonical Ltd.
+#
+#    Author: Scott Moser <scott.moser@canonical.com>
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License version 3, as
+#    published by the Free Software Foundation.
+#
+#    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, see <http://www.gnu.org/licenses/>.
+
+import os
+import os.path
+import re
+import stat
+
+from cloudinit import log as logging
+from cloudinit.settings import PER_ALWAYS
+from cloudinit import util
+
+frequency = PER_ALWAYS
+
+DEFAULT_CONFIG = {
+    'mode': 'auto',
+    'devices': ['/'],
+}
+
+
+def enum(**enums):
+    return type('Enum', (), enums)
+
+
+RESIZE = enum(SKIPPED="SKIPPED", CHANGED="CHANGED", NOCHANGE="NOCHANGE",
+              FAILED="FAILED")
+
+LOG = logging.getLogger(__name__)
+
+
+def resizer_factory(mode):
+    resize_class = None
+    if mode == "auto":
+        for (_name, resizer) in RESIZERS:
+            cur = resizer()
+            if cur.available():
+                resize_class = cur
+                break
+
+        if not resize_class:
+            raise ValueError("No resizers available")
+
+    else:
+        mmap = {}
+        for (k, v) in RESIZERS:
+            mmap[k] = v
+
+        if mode not in mmap:
+            raise TypeError("unknown resize mode %s" % mode)
+
+        mclass = mmap[mode]()
+        if mclass.available():
+            resize_class = mclass
+
+        if not resize_class:
+            raise ValueError("mode %s not available" % mode)
+
+    return resize_class
+
+
+class ResizeFailedException(Exception):
+    pass
+
+
+class ResizeParted(object):
+    def available(self):
+        myenv = os.environ.copy()
+        myenv['LANG'] = 'C'
+
+        try:
+            (out, _err) = util.subp(["parted", "--help"], env=myenv)
+            if re.search(r"COMMAND.*resizepart\s+", out, re.DOTALL):
+                return True
+
+        except util.ProcessExecutionError:
+            pass
+        return False
+
+    def resize(self, diskdev, partnum, partdev):
+        before = get_size(partdev)
+        try:
+            util.subp(["parted", "resizepart", diskdev, partnum])
+        except util.ProcessExecutionError as e:
+            raise ResizeFailedException(e)
+
+        return (before, get_size(partdev))
+
+
+class ResizeGrowPart(object):
+    def available(self):
+        myenv = os.environ.copy()
+        myenv['LANG'] = 'C'
+
+        try:
+            (out, _err) = util.subp(["growpart", "--help"], env=myenv)
+            if re.search(r"--update\s+", out, re.DOTALL):
+                return True
+
+        except util.ProcessExecutionError:
+            pass
+        return False
+
+    def resize(self, diskdev, partnum, partdev):
+        before = get_size(partdev)
+        try:
+            util.subp(["growpart", '--dry-run', diskdev, partnum])
+        except util.ProcessExecutionError as e:
+            if e.exit_code != 1:
+                util.logexc(LOG, ("Failed growpart --dry-run for (%s, %s)" %
+                                  (diskdev, partnum)))
+                raise ResizeFailedException(e)
+            return (before, before)
+
+        try:
+            util.subp(["growpart", diskdev, partnum])
+        except util.ProcessExecutionError as e:
+            util.logexc(LOG, "Failed: growpart %s %s" % (diskdev, partnum))
+            raise ResizeFailedException(e)
+
+        return (before, get_size(partdev))
+
+
+def get_size(filename):
+    fd = os.open(filename, os.O_RDONLY)
+    try:
+        return os.lseek(fd, 0, os.SEEK_END)
+    finally:
+        os.close(fd)
+
+
+def device_part_info(devpath):
+    # convert an entry in /dev/ to parent disk and partition number
+
+    # input of /dev/vdb or /dev/disk/by-label/foo
+    # rpath is hopefully a real-ish path in /dev (vda, sdb..)
+    rpath = os.path.realpath(devpath)
+
+    bname = os.path.basename(rpath)
+    syspath = "/sys/class/block/%s" % bname
+
+    if not os.path.exists(syspath):
+        raise ValueError("%s had no syspath (%s)" % (devpath, syspath))
+
+    ptpath = os.path.join(syspath, "partition")
+    if not os.path.exists(ptpath):
+        raise TypeError("%s not a partition" % devpath)
+
+    ptnum = util.load_file(ptpath).rstrip()
+
+    # for a partition, real syspath is something like:
+    # /sys/devices/pci0000:00/0000:00:04.0/virtio1/block/vda/vda1
+    rsyspath = os.path.realpath(syspath)
+    disksyspath = os.path.dirname(rsyspath)
+
+    diskmajmin = util.load_file(os.path.join(disksyspath, "dev")).rstrip()
+    diskdevpath = os.path.realpath("/dev/block/%s" % diskmajmin)
+
+    # diskdevpath has something like 253:0
+    # and udev has put links in /dev/block/253:0 to the device name in /dev/
+    return (diskdevpath, ptnum)
+
+
+def devent2dev(devent):
+    if devent.startswith("/dev/"):
+        return devent
+    else:
+        result = util.get_mount_info(devent)
+        if not result:
+            raise ValueError("Could not determine device of '%s' % dev_ent")
+        return result[0]
+
+
+def resize_devices(resizer, devices):
+    # returns a tuple of tuples containing (entry-in-devices, action, message)
+    info = []
+    for devent in devices:
+        try:
+            blockdev = devent2dev(devent)
+        except ValueError as e:
+            info.append((devent, RESIZE.SKIPPED,
+                         "unable to convert to device: %s" % e,))
+            continue
+
+        try:
+            statret = os.stat(blockdev)
+        except OSError as e:
+            info.append((devent, RESIZE.SKIPPED,
+                         "stat of '%s' failed: %s" % (blockdev, e),))
+            continue
+
+        if not stat.S_ISBLK(statret.st_mode):
+            info.append((devent, RESIZE.SKIPPED,
+                         "device '%s' not a block device" % blockdev,))
+            continue
+
+        try:
+            (disk, ptnum) = device_part_info(blockdev)
+        except (TypeError, ValueError) as e:
+            info.append((devent, RESIZE.SKIPPED,
+                         "device_part_info(%s) failed: %s" % (blockdev, e),))
+            continue
+
+        try:
+            (old, new) = resizer.resize(disk, ptnum, blockdev)
+            if old == new:
+                info.append((devent, RESIZE.NOCHANGE,
+                             "no change necessary (%s, %s)" % (disk, ptnum),))
+            else:
+                info.append((devent, RESIZE.CHANGED,
+                             "changed (%s, %s) from %s to %s" %
+                             (disk, ptnum, old, new),))
+
+        except ResizeFailedException as e:
+            info.append((devent, RESIZE.FAILED,
+                         "failed to resize: disk=%s, ptnum=%s: %s" %
+                         (disk, ptnum, e),))
+
+    return info
+
+
+def handle(_name, cfg, _cloud, log, _args):
+    if 'growpart' not in cfg:
+        log.debug("No 'growpart' entry in cfg.  Using default: %s" %
+                  DEFAULT_CONFIG)
+        cfg['growpart'] = DEFAULT_CONFIG
+
+    mycfg = cfg.get('growpart')
+    if not isinstance(mycfg, dict):
+        log.warn("'growpart' in config was not a dict")
+        return
+
+    mode = mycfg.get('mode', "auto")
+    if util.is_false(mode):
+        log.debug("growpart disabled: mode=%s" % mode)
+        return
+
+    devices = util.get_cfg_option_list(cfg, "devices", ["/"])
+    if not len(devices):
+        log.debug("growpart: empty device list")
+        return
+
+    try:
+        resizer = resizer_factory(mode)
+    except (ValueError, TypeError) as e:
+        log.debug("growpart unable to find resizer for '%s': %s" % (mode, e))
+        if mode != "auto":
+            raise e
+        return
+
+    resized = resize_devices(resizer, devices)
+    for (entry, action, msg) in resized:
+        if action == RESIZE.CHANGED:
+            log.info("'%s' resized: %s" % (entry, msg))
+        else:
+            log.debug("'%s' %s: %s" % (entry, action, msg))
+
+RESIZERS = (('parted', ResizeParted), ('growpart', ResizeGrowPart))