Cmdline tool to grow private.img (#5)

dom0/qvm-core/qubes.py

@@ -473,6 +473,11 @@ class QubesVm(object):
 
         return os.path.getsize(self.private_img)
 
+    def resize_private_img(self, size):
+        f_private = open (self.private_img, "a+b")
+        f_private.truncate (size)
+        f_private.close ()
+
     def create_xenstore_entries(self, xid):
         if dry_run:
             return

dom0/qvm-tools/qvm-grow-private

@@ -0,0 +1,109 @@
+#!/usr/bin/python2.6
+#
+# The Qubes OS Project, http://www.qubes-os.org
+#
+# Copyright (C) 2011  Marek Marczykowski <marmarek@mimuw.edu.pl>
+#
+# 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; either version 2
+# of the License, or (at your option) any later version.
+#
+# 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+#
+
+from qubes.qubes import QubesVmCollection
+from qubes.qubes import QubesException
+from optparse import OptionParser
+import subprocess
+import os
+import re
+
+qvm_run_path = "/usr/bin/qvm-run"
+
+def parse_size(size):
+    units = [ ('K', 1024), ('KB', 1024),
+        ('M', 1024*1024), ('MB', 1024*1024),
+        ('G', 1024*1024*1024), ('GB', 1024*1024*1024),
+    ]
+
+    size = size.strip().upper()
+    if size.isdigit():
+        return size
+
+    for unit, multiplier in units:
+        if size.endswith(unit):
+            size = size[:-len(unit)].strip()
+            return int(size)*multiplier
+    
+    print "Invalid size: {0}.".format(size)
+    exit(1)
+
+def main():
+    usage = "usage: %prog <vm-name> <size>"
+    parser = OptionParser (usage)
+
+    (options, args) = parser.parse_args ()
+    if (len (args) != 2):
+        parser.error ("You must specify VM name and new size!")
+    vmname = args[0]
+    size = args[1]
+
+    qvm_collection = QubesVmCollection()
+    qvm_collection.lock_db_for_reading()
+    qvm_collection.load()
+    qvm_collection.unlock_db()
+
+    vm = qvm_collection.get_vm_by_name(vmname)
+    if vm is None:
+        print "A VM with the name '{0}' does not exist in the system.".format(vmname)
+        exit(1)
+
+    if vm.is_running() and os.geteuid() != 0:
+        print "You must be root to grow private.img on running VM."
+        exit(1)
+
+    size_bytes = parse_size(size)
+
+    if size_bytes < vm.get_private_img_sz():
+        print "Cannot shrink private.img ({0} < {1})".format(size_bytes, vm.get_private_img_sz())
+        exit(1)
+
+    try:
+        vm.resize_private_img(size_bytes)
+    except (IOError, OSError, QubesException) as err:
+        print "ERROR: {0}".format(err)
+        exit (1)
+
+    if vm.is_running():
+        # find loop device
+        p = subprocess.Popen (["losetup", "--associated", vm.private_img],
+                stdout=subprocess.PIPE)
+        result = p.communicate()
+        m = re.match(r"^(/dev/loop\d+):\s", result[0])
+        if m is None:
+            print "ERROR: Cannot find loop device!"
+            exit(1)
+
+        loop_dev = m.group(1)
+
+        # resize loop device
+        retcode = subprocess.check_call(["losetup", "--set-capacity", loop_dev])
+
+        retcode = subprocess.check_call([qvm_run_path, "-uroot", vmname, 
+                "resize2fs /dev/xvdb" ])
+    else:
+        retcode = subprocess.check_call(["resize2fs", "-f", vm.private_img])
+        
+	exit (0)
+
+
+main()