Implement extend volume for Storwize/SVC.

This implements the extend volume functionality for the Storwize/SVC
driver.  Extending volumes with snapshots is not supported, as this
will require converting the snapshots into full copies, which will eat
up free space.

Change-Id: I5fb8c6967e6f3df1adfef46e05c832a953dd7131

diff --git a/cinder/tests/test_storwize_svc.py b/cinder/tests/test_storwize_svc.py
index 8b477226b28f75551a03ad97db4010581788e06f..02b1b59b2a2f045abcc3f3f136db99fff78d7ca5 100644 (file)
--- a/cinder/tests/test_storwize_svc.py
+++ b/cinder/tests/test_storwize_svc.py
@@ -35,6 +35,7 @@ from cinder import exception
 from cinder.openstack.common import excutils
 from cinder.openstack.common import log as logging
 from cinder import test
+from cinder import units
 from cinder import utils
 from cinder.volume import configuration as conf
 from cinder.volume.drivers import storwize_svc
@@ -581,6 +582,24 @@ port_speed!N/A
         del self._volumes_list[vol_name]
         return ('', '')
 
+    def _cmd_expandvdisksize(self, **kwargs):
+        if 'obj' not in kwargs:
+            return self._errors['CMMVC5701E']
+        vol_name = kwargs['obj'].strip('\'\'')
+
+        # Assume unit is gb
+        if 'size' not in kwargs:
+            return self._errors['CMMVC5707E']
+        size = int(kwargs['size'])
+
+        if vol_name not in self._volumes_list:
+            return self._errors['CMMVC5753E']
+
+        curr_size = int(self._volumes_list[vol_name]['capacity'])
+        addition = size * units.GiB
+        self._volumes_list[vol_name]['capacity'] = str(curr_size + addition)
+        return ('', '')
+
     def _get_fcmap_info(self, vol_name):
         ret_vals = {
             'fc_id': '',
@@ -1157,6 +1176,8 @@ port_speed!N/A
             out, err = self._cmd_mkvdisk(**kwargs)
         elif command == 'rmvdisk':
             out, err = self._cmd_rmvdisk(**kwargs)
+        elif command == 'expandvdisksize':
+            out, err = self._cmd_expandvdisksize(**kwargs)
         elif command == 'lsvdisk':
             out, err = self._cmd_lsvdisk(**kwargs)
         elif command == 'mkhost':
@@ -1937,6 +1958,24 @@ class StorwizeSVCDriverTestCase(test.TestCase):
             self.assertAlmostEqual(stats['total_capacity_gb'], 3328.0)
             self.assertAlmostEqual(stats['free_capacity_gb'], 3287.5)
 
+    def test_storwize_svc_extend_volume(self):
+        volume = self._generate_vol_info(None, None)
+        self.driver.db.volume_set(volume)
+        self.driver.create_volume(volume)
+        stats = self.driver.extend_volume(volume, '13')
+        attrs = self.driver._get_vdisk_attributes(volume['name'])
+        vol_size = int(attrs['capacity']) / units.GiB
+        self.assertAlmostEqual(vol_size, 13)
+
+        snap = self._generate_vol_info(volume['name'], volume['id'])
+        self.driver.create_snapshot(snap)
+        self._assert_vol_exists(snap['name'], True)
+        self.assertRaises(exception.VolumeBackendAPIException,
+                          self.driver.extend_volume, volume, '16')
+
+        self.driver.delete_snapshot(snap)
+        self.driver.delete_volume(volume)
+
 
 class CLIResponseTestCase(test.TestCase):
     def test_empty(self):

diff --git a/cinder/volume/drivers/storwize_svc.py b/cinder/volume/drivers/storwize_svc.py
index ad545c09f59831f59472c48c1c9dde4236c81db7..c2ed2ebcd89cbe4e4b5f94a39ee28ab568b85c46 100755 (executable)
--- a/cinder/volume/drivers/storwize_svc.py
+++ b/cinder/volume/drivers/storwize_svc.py
@@ -1185,35 +1185,7 @@ class StorwizeSVCDriver(san.SanISCSIDriver):
         else:
             return True
 
-    def _delete_vdisk(self, name, force):
-        """Deletes existing vdisks.
-
-        It is very important to properly take care of mappings before deleting
-        the disk:
-        1. If no mappings, then it was a vdisk, and can be deleted
-        2. If it is the source of a flashcopy mapping and copy_rate is 0, then
-           it is a vdisk that has a snapshot.  If the force flag is set,
-           delete the mapping and the vdisk, otherwise set the mapping to
-           copy and wait (this will allow users to delete vdisks that have
-           snapshots if/when the upper layers allow it).
-        3. If it is the target of a mapping and copy_rate is 0, it is a
-           snapshot, and we should properly stop the mapping and delete.
-        4. If it is the source/target of a mapping and copy_rate is not 0, it
-           is a clone or vdisk created from a snapshot.  We wait for the copy
-           to complete (the mapping will be autodeleted) and then delete the
-           vdisk.
-
-        """
-
-        LOG.debug(_('enter: _delete_vdisk: vdisk %s') % name)
-
-        # Try to delete volume only if found on the storage
-        vdisk_defined = self._is_vdisk_defined(name)
-        if not vdisk_defined:
-            LOG.info(_('warning: Tried to delete vdisk %s but it does not '
-                       'exist.') % name)
-            return
-
+    def _ensure_vdisk_no_fc_mappings(self, name, allow_snaps=True):
         # Ensure vdisk has no FlashCopy mappings
         mapping_ids = self._get_vdisk_fc_mappings(name)
         while len(mapping_ids):
@@ -1230,10 +1202,12 @@ class StorwizeSVCDriver(san.SanISCSIDriver):
                 if copy_rate == '0':
                     # Case #2: A vdisk that has snapshots
                     if source == name:
-                            ssh_cmd = ('svctask chfcmap -copyrate 50 '
-                                       '-autodelete on %s' % map_id)
-                            out, err = self._run_ssh(ssh_cmd)
-                            wait_for_copy = True
+                        if not allow_snaps:
+                            return False
+                        ssh_cmd = ('svctask chfcmap -copyrate 50 '
+                                   '-autodelete on %s' % map_id)
+                        out, err = self._run_ssh(ssh_cmd)
+                        wait_for_copy = True
                     # Case #3: A snapshot
                     else:
                         msg = (_('Vdisk %(name)s not involved in '
@@ -1259,6 +1233,38 @@ class StorwizeSVCDriver(san.SanISCSIDriver):
             if wait_for_copy:
                 time.sleep(5)
             mapping_ids = self._get_vdisk_fc_mappings(name)
+        return True
+
+    def _delete_vdisk(self, name, force):
+        """Deletes existing vdisks.
+
+        It is very important to properly take care of mappings before deleting
+        the disk:
+        1. If no mappings, then it was a vdisk, and can be deleted
+        2. If it is the source of a flashcopy mapping and copy_rate is 0, then
+           it is a vdisk that has a snapshot.  If the force flag is set,
+           delete the mapping and the vdisk, otherwise set the mapping to
+           copy and wait (this will allow users to delete vdisks that have
+           snapshots if/when the upper layers allow it).
+        3. If it is the target of a mapping and copy_rate is 0, it is a
+           snapshot, and we should properly stop the mapping and delete.
+        4. If it is the source/target of a mapping and copy_rate is not 0, it
+           is a clone or vdisk created from a snapshot.  We wait for the copy
+           to complete (the mapping will be autodeleted) and then delete the
+           vdisk.
+
+        """
+
+        LOG.debug(_('enter: _delete_vdisk: vdisk %s') % name)
+
+        # Try to delete volume only if found on the storage
+        vdisk_defined = self._is_vdisk_defined(name)
+        if not vdisk_defined:
+            LOG.info(_('warning: Tried to delete vdisk %s but it does not '
+                       'exist.') % name)
+            return
+
+        self._ensure_vdisk_no_fc_mappings(name)
 
         forceflag = '-force' if force else ''
         cmd_params = {'frc': forceflag, 'name': name}
@@ -1338,6 +1344,24 @@ class StorwizeSVCDriver(san.SanISCSIDriver):
         else:
             raise NotImplementedError()
 
+    def extend_volume(self, volume, new_size):
+        LOG.debug(_('enter: extend_volume: volume %s') % volume['id'])
+        ret = self._ensure_vdisk_no_fc_mappings(volume['name'],
+                                                allow_snaps=False)
+        if not ret:
+            exception_message = (_('extend_volume: Extending a volume with '
+                                   'snapshots is not supported.'))
+            raise exception.VolumeBackendAPIException(data=exception_message)
+
+        extend_amt = int(new_size) - volume['size']
+        ssh_cmd = ('svctask expandvdisksize -size %(amt)d -unit gb %(name)s'
+                   % {'amt': extend_amt, 'name': volume['name']})
+        out, err = self._run_ssh(ssh_cmd)
+        # No output should be returned from expandvdisksize
+        self._assert_ssh_return(len(out.strip()) == 0, 'extend_volume',
+                                ssh_cmd, out, err)
+        LOG.debug(_('leave: extend_volume: volume %s') % volume['id'])
+
     """====================================================================="""
     """ MISC/HELPERS                                                        """
     """====================================================================="""