Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2019-1…

…1-26' into staging

Block patches for 4.2.0-rc3:
- Fix for shared storage migration with persistent dirty bitmaps

# gpg: Signature made Tue 26 Nov 2019 13:27:32 GMT
# gpg:                using RSA key 91BEB60A30DB3E8857D11829F407DB0061D5CF40
# gpg:                issuer "mreitz@redhat.com"
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>" [full]
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* remotes/maxreitz/tags/pull-block-2019-11-26:
  iotests: add new test cases to bitmap migration
  block/qcow2-bitmap: fix bitmap migration

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

block/qcow2-bitmap.c

@@ -988,7 +988,26 @@ bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp)
     }
 
     QSIMPLEQ_FOREACH(bm, bm_list, entry) {
-        BdrvDirtyBitmap *bitmap = load_bitmap(bs, bm, errp);
+        BdrvDirtyBitmap *bitmap;
+
+        if ((bm->flags & BME_FLAG_IN_USE) &&
+            bdrv_find_dirty_bitmap(bs, bm->name))
+        {
+            /*
+             * We already have corresponding BdrvDirtyBitmap, and bitmap in the
+             * image is marked IN_USE. Firstly, this state is valid, no reason
+             * to consider existing BdrvDirtyBitmap to be bad. Secondly it's
+             * absolutely possible, when we do migration with shared storage
+             * with dirty-bitmaps capability enabled: if the bitmap was loaded
+             * from this storage before migration start, the storage will
+             * of-course contain IN_USE outdated version of the bitmap, and we
+             * should not load it on migration target, as we already have this
+             * bitmap, being migrated.
+             */
+            continue;
+        }
+
+        bitmap = load_bitmap(bs, bm, errp);
         if (bitmap == NULL) {
             goto fail;
         }

tests/qemu-iotests/169

@@ -134,23 +134,21 @@ class TestDirtyBitmapMigration(iotests.QMPTestCase):
         self.check_bitmap(self.vm_a, sha256 if persistent else False)
 
     def do_test_migration(self, persistent, migrate_bitmaps, online,
-                          shared_storage):
+                          shared_storage, pre_shutdown):
         granularity = 512
 
         # regions = ((start, count), ...)
         regions = ((0, 0x10000),
                    (0xf0000, 0x10000),
                    (0xa0201, 0x1000))
 
-        should_migrate = migrate_bitmaps or persistent and shared_storage
+        should_migrate = \
+            (migrate_bitmaps and (persistent or not pre_shutdown)) or \
+            (persistent and shared_storage)
         mig_caps = [{'capability': 'events', 'state': True}]
         if migrate_bitmaps:
             mig_caps.append({'capability': 'dirty-bitmaps', 'state': True})
 
-        result = self.vm_a.qmp('migrate-set-capabilities',
-                               capabilities=mig_caps)
-        self.assert_qmp(result, 'return', {})
-
         self.vm_b.add_incoming(incoming_cmd if online else "defer")
         self.vm_b.add_drive(disk_a if shared_storage else disk_b)
 
@@ -166,6 +164,14 @@ class TestDirtyBitmapMigration(iotests.QMPTestCase):
             self.vm_a.hmp_qemu_io('drive0', 'write %d %d' % r)
         sha256 = self.get_bitmap_hash(self.vm_a)
 
+        if pre_shutdown:
+            self.vm_a.shutdown()
+            self.vm_a.launch()
+
+        result = self.vm_a.qmp('migrate-set-capabilities',
+                               capabilities=mig_caps)
+        self.assert_qmp(result, 'return', {})
+
         result = self.vm_a.qmp('migrate', uri=mig_cmd)
         while True:
             event = self.vm_a.event_wait('MIGRATION')
@@ -210,11 +216,13 @@ def inject_test_case(klass, name, method, *args, **kwargs):
     mc = operator.methodcaller(method, *args, **kwargs)
     setattr(klass, 'test_' + method + name, lambda self: mc(self))
 
-for cmb in list(itertools.product((True, False), repeat=4)):
+for cmb in list(itertools.product((True, False), repeat=5)):
     name = ('_' if cmb[0] else '_not_') + 'persistent_'
     name += ('_' if cmb[1] else '_not_') + 'migbitmap_'
     name += '_online' if cmb[2] else '_offline'
     name += '_shared' if cmb[3] else '_nonshared'
+    if (cmb[4]):
+        name += '__pre_shutdown'
 
     inject_test_case(TestDirtyBitmapMigration, name, 'do_test_migration',
                      *list(cmb))

tests/qemu-iotests/169.out

@@ -1,5 +1,5 @@
-....................
+....................................
 ----------------------------------------------------------------------
-Ran 20 tests
+Ran 36 tests
 
 OK