update iscsi ro prop if zvol readonly changes

(cherry picked from commit 9a264ed)

src/middlewared/middlewared/plugins/iscsi_/global_linux.py

@@ -3,6 +3,7 @@
 
 from middlewared.schema import Bool, Dict, Int, Str
 from middlewared.service import filterable, filterable_returns, private, Service
+from middlewared.service_exception import MatchNotFound
 from middlewared.utils import filter_list, run
 
 
@@ -94,6 +95,22 @@ def sessions(self, filters, options):
                 sessions.append(session_dict)
         return filter_list(sessions, filters, options)
 
+    @private
+    def resync_readonly_property_for_zvol(self, id_, read_only_value):
+        if not self.middleware.call_sync('service.started', 'iscsitarget'):
+            return
+
+        try:
+            extent = self.middleware.call_sync(
+                'iscsi.extent.query',
+                [['enabled', '=', True], ['path', '=', f'zvol/{id_}']],
+                {'get': True}
+            )
+            ro = True if read_only_value.lower() == 'on' else False
+            self.middleware.call_sync('iscsi.extent.update', extent['id'], {'ro': ro})
+        except MatchNotFound:
+            return
+
     @private
     def resync_lun_size_for_zvol(self, id_):
         if not self.middleware.call_sync('service.started', 'iscsitarget'):

src/middlewared/middlewared/plugins/pool_/dataset.py

@@ -939,10 +939,18 @@ async def do_update(self, audit_callback, id_, data):
             verrors.add_child('pool_dataset_update', self.__handle_zfs_set_property_error(e, properties_definitions))
             raise verrors
 
-        if data['type'] == 'VOLUME' and 'volsize' in data and data['volsize'] > dataset[0]['volsize']['parsed']:
-            # means the zvol size has increased so we need to check if this zvol is shared via SCST (iscsi)
-            # and if it is, resync it so the connected initiators can see the new size of the zvol
-            await self.middleware.call('iscsi.global.resync_lun_size_for_zvol', id_)
+        if data['type'] == 'VOLUME':
+            if 'volsize' in data and data['volsize'] > dataset[0]['volsize']['parsed']:
+                # means the zvol size has increased so we need to check if this zvol is shared via SCST (iscsi)
+                # and if it is, resync it so the connected initiators can see the new size of the zvol
+                await self.middleware.call('iscsi.global.resync_lun_size_for_zvol', id_)
+
+            if 'readonly' in data:
+                # depending on the iscsi client connected to us, if someone marks a zvol
+                # as R/O (or R/W), we need to be sure and update the associated extent so
+                # that we don't get into a scenario where the iscsi extent is R/W but the
+                # underlying zvol is R/O. Windows clients seem to not handle this very well.
+                await self.middleware.call('iscsi.global.resync_readonly_property_for_zvol', id_)
 
         updated_ds = await self.get_instance(id_)
         self.middleware.send_event('pool.dataset.query', 'CHANGED', id=id_, fields=updated_ds)