diff --git a/manila/share/drivers/helpers.py b/manila/share/drivers/helpers.py
index bdf6a9b342..d7a257dbc7 100644
--- a/manila/share/drivers/helpers.py
+++ b/manila/share/drivers/helpers.py
@@ -529,6 +529,30 @@ class CIFSHelperIPAccess(CIFSHelperBase):
         ]
         self._ssh_exec(server, backup_exports)
         self._set_allow_hosts(server, [], share_name)
+        self._kick_out_users(server, share_name)
+
+    def _kick_out_users(self, server, share_name):
+        """Kick out all users of share"""
+        (out, _) = self._ssh_exec(server, ['sudo', 'smbstatus', '-S'])
+
+        shares = []
+        header = True
+        regexp = r"^(?P<share>[^ ]+)\s+(?P<pid>[0-9]+)\s+(?P<machine>[^ ]+).*"
+        for line in out.splitlines():
+            line = line.strip()
+            if not header and line:
+                match = re.match(regexp, line)
+                if match:
+                    shares.append(match.groupdict())
+                else:
+                    raise exception.ShareBackendException(
+                        msg="Failed to obtain smbstatus for %s!" % share_name)
+            elif line.startswith('----'):
+                header = False
+        to_kill = [s['pid'] for s in shares if
+                   share_name == s['share'] or share_name is None]
+        if to_kill:
+            self._ssh_exec(server, ['sudo', 'kill', '-15'] + to_kill)
 
     def restore_access_after_maintenance(self, server, share_name):
         maintenance_file = self._get_maintenance_file_path(share_name)
diff --git a/manila/tests/share/drivers/test_helpers.py b/manila/tests/share/drivers/test_helpers.py
index c7f6ad6c12..873c3c7a5c 100644
--- a/manila/tests/share/drivers/test_helpers.py
+++ b/manila/tests/share/drivers/test_helpers.py
@@ -678,11 +678,39 @@ class CIFSHelperIPAccessTestCase(test.TestCase):
             self.server_details, self.share_name)
         self._helper._set_allow_hosts.assert_called_once_with(
             self.server_details, [], self.share_name)
+        kickoff_user_cmd = ['sudo', 'smbstatus', '-S']
+        self._helper._ssh_exec.assert_any_call(
+            self.server_details, kickoff_user_cmd)
         valid_cmd = ['echo', "'test test2'", '|', 'sudo', 'tee',
                      maintenance_path]
-        self._helper._ssh_exec.assert_called_once_with(
+        self._helper._ssh_exec.assert_any_call(
             self.server_details, valid_cmd)
 
+    def test__kick_out_users_success(self):
+        smbstatus_return = """Service      pid     machine       Connected at
+-------------------------------------------------------
+fake_share_name   1001   fake_machine1    Thu Sep 14 14:59:07 2017
+fake_share_name   1002   fake_machine2    Thu Sep 14 14:59:07 2017
+"""
+        self.mock_object(self._helper, '_ssh_exec', mock.Mock(
+            side_effect=[(smbstatus_return, "fake_stderr"), ("fake", "fake")]))
+        self._helper._kick_out_users(self.server_details, self.share_name)
+        self._helper._ssh_exec.assert_any_call(
+            self.server_details, ['sudo', 'smbstatus', '-S'])
+        self._helper._ssh_exec.assert_any_call(
+            self.server_details, ["sudo", "kill", "-15", "1001", "1002"])
+
+    def test__kick_out_users_failed(self):
+        smbstatus_return = """Service      pid     machine       Connected at
+-------------------------------------------------------
+fake line
+"""
+        self.mock_object(self._helper, '_ssh_exec', mock.Mock(
+            return_value=(smbstatus_return, "fake_stderr")))
+        self.assertRaises(exception.ShareBackendException,
+                          self._helper._kick_out_users, self.server_details,
+                          self.share_name)
+
     def test_restore_access_after_maintenance(self):
         fake_maintenance_path = "test.path"
         self.mock_object(self._helper, '_set_allow_hosts')
diff --git a/releasenotes/notes/bug-1703581-cifs-extension-failing-because-of-volume-in-use-3fea31c4a58e2f1b.yaml b/releasenotes/notes/bug-1703581-cifs-extension-failing-because-of-volume-in-use-3fea31c4a58e2f1b.yaml
new file mode 100644
index 0000000000..910bf7a2ec
--- /dev/null
+++ b/releasenotes/notes/bug-1703581-cifs-extension-failing-because-of-volume-in-use-3fea31c4a58e2f1b.yaml
@@ -0,0 +1,4 @@
+---
+fixes:
+  - Fixed the Generic driver to evict and kill any user processes accessing
+    a share before attempting to extend or shrink a CIFS share.