Merge remote-tracking branch 'remotes/jnsnow/tags/bitmaps-pull-request' into staging

Pull request

# gpg: Signature made Wed 29 May 2019 00:58:33 BST
# gpg:                using RSA key F9B7ABDBBCACDF95BE76CBD07DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>" [full]
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/bitmaps-pull-request:
  iotests: test external snapshot with bitmap copying
  qapi: support external bitmaps in block-dirty-bitmap-merge
  migration/dirty-bitmaps: change bitmap enumeration method

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

7 files changed, 167 insertions, 33 deletions

diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 59e6ebb861..49646a30e6 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -816,10 +816,10 @@ void bdrv_merge_dirty_bitmap(BdrvDirtyBitmap *dest, const BdrvDirtyBitmap *src,
 {
     bool ret;
 
-    /* only bitmaps from one bds are supported */
-    assert(dest->mutex == src->mutex);
-
     qemu_mutex_lock(dest->mutex);
+    if (src->mutex != dest->mutex) {
+        qemu_mutex_lock(src->mutex);
+    }
 
     if (bdrv_dirty_bitmap_check(dest, BDRV_BITMAP_DEFAULT, errp)) {
         goto out;
@@ -845,4 +845,7 @@ void bdrv_merge_dirty_bitmap(BdrvDirtyBitmap *dest, const BdrvDirtyBitmap *src,
 
 out:
     qemu_mutex_unlock(dest->mutex);
+    if (src->mutex != dest->mutex) {
+        qemu_mutex_unlock(src->mutex);
+    }
 }
diff --git a/blockdev.c b/blockdev.c
index bc339d7818..17c2d801d7 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2112,11 +2112,10 @@ static void block_dirty_bitmap_disable_abort(BlkActionState *common)
     }
 }
 
-static BdrvDirtyBitmap *do_block_dirty_bitmap_merge(const char *node,
-                                                    const char *target,
-                                                    strList *bitmaps,
-                                                    HBitmap **backup,
-                                                    Error **errp);
+static BdrvDirtyBitmap *do_block_dirty_bitmap_merge(
+        const char *node, const char *target,
+        BlockDirtyBitmapMergeSourceList *bitmaps,
+        HBitmap **backup, Error **errp);
 
 static void block_dirty_bitmap_merge_prepare(BlkActionState *common,
                                              Error **errp)
@@ -2965,15 +2964,14 @@ void qmp_block_dirty_bitmap_disable(const char *node, const char *name,
     bdrv_disable_dirty_bitmap(bitmap);
 }
 
-static BdrvDirtyBitmap *do_block_dirty_bitmap_merge(const char *node,
-                                                    const char *target,
-                                                    strList *bitmaps,
-                                                    HBitmap **backup,
-                                                    Error **errp)
+static BdrvDirtyBitmap *do_block_dirty_bitmap_merge(
+        const char *node, const char *target,
+        BlockDirtyBitmapMergeSourceList *bitmaps,
+        HBitmap **backup, Error **errp)
 {
     BlockDriverState *bs;
     BdrvDirtyBitmap *dst, *src, *anon;
-    strList *lst;
+    BlockDirtyBitmapMergeSourceList *lst;
     Error *local_err = NULL;
 
     dst = block_dirty_bitmap_lookup(node, target, &bs, errp);
@@ -2988,11 +2986,28 @@ static BdrvDirtyBitmap *do_block_dirty_bitmap_merge(const char *node,
     }
 
     for (lst = bitmaps; lst; lst = lst->next) {
-        src = bdrv_find_dirty_bitmap(bs, lst->value);
-        if (!src) {
-            error_setg(errp, "Dirty bitmap '%s' not found", lst->value);
-            dst = NULL;
-            goto out;
+        switch (lst->value->type) {
+            const char *name, *node;
+        case QTYPE_QSTRING:
+            name = lst->value->u.local;
+            src = bdrv_find_dirty_bitmap(bs, name);
+            if (!src) {
+                error_setg(errp, "Dirty bitmap '%s' not found", name);
+                dst = NULL;
+                goto out;
+            }
+            break;
+        case QTYPE_QDICT:
+            node = lst->value->u.external.node;
+            name = lst->value->u.external.name;
+            src = block_dirty_bitmap_lookup(node, name, NULL, errp);
+            if (!src) {
+                dst = NULL;
+                goto out;
+            }
+            break;
+        default:
+            abort();
         }
 
         bdrv_merge_dirty_bitmap(anon, src, NULL, &local_err);
@@ -3012,7 +3027,8 @@ static BdrvDirtyBitmap *do_block_dirty_bitmap_merge(const char *node,
 }
 
 void qmp_block_dirty_bitmap_merge(const char *node, const char *target,
-                                  strList *bitmaps, Error **errp)
+                                  BlockDirtyBitmapMergeSourceList *bitmaps,
+                                  Error **errp)
 {
     do_block_dirty_bitmap_merge(node, target, bitmaps, NULL, errp);
 }
diff --git a/migration/block-dirty-bitmap.c b/migration/block-dirty-bitmap.c
index d1bb863cb6..4a896a09eb 100644
--- a/migration/block-dirty-bitmap.c
+++ b/migration/block-dirty-bitmap.c
@@ -273,7 +273,6 @@ static int init_dirty_bitmap_migration(void)
     BlockDriverState *bs;
     BdrvDirtyBitmap *bitmap;
     DirtyBitmapMigBitmapState *dbms;
-    BdrvNextIterator it;
     Error *local_err = NULL;
 
     dirty_bitmap_mig_state.bulk_completed = false;
@@ -281,13 +280,8 @@ static int init_dirty_bitmap_migration(void)
     dirty_bitmap_mig_state.prev_bitmap = NULL;
     dirty_bitmap_mig_state.no_bitmaps = false;
 
-    for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
-        const char *drive_name = bdrv_get_device_or_node_name(bs);
-
-        /* skip automatically inserted nodes */
-        while (bs && bs->drv && bs->implicit) {
-            bs = backing_bs(bs);
-        }
+    for (bs = bdrv_next_all_states(NULL); bs; bs = bdrv_next_all_states(bs)) {
+        const char *name = bdrv_get_device_or_node_name(bs);
 
         for (bitmap = bdrv_dirty_bitmap_next(bs, NULL); bitmap;
              bitmap = bdrv_dirty_bitmap_next(bs, bitmap))
@@ -296,7 +290,7 @@ static int init_dirty_bitmap_migration(void)
                 continue;
             }
 
-            if (drive_name == NULL) {
+            if (!name || strcmp(name, "") == 0) {
                 error_report("Found bitmap '%s' in unnamed node %p. It can't "
                              "be migrated", bdrv_dirty_bitmap_name(bitmap), bs);
                 goto fail;
@@ -313,7 +307,7 @@ static int init_dirty_bitmap_migration(void)
 
             dbms = g_new0(DirtyBitmapMigBitmapState, 1);
             dbms->bs = bs;
-            dbms->node_name = drive_name;
+            dbms->node_name = name;
             dbms->bitmap = bitmap;
             dbms->total_sectors = bdrv_nb_sectors(bs);
             dbms->sectors_per_chunk = CHUNK_SIZE * 8 *
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 3e4042be7f..1defcde048 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -2004,18 +2004,34 @@
             '*persistent': 'bool', '*autoload': 'bool', '*disabled': 'bool' } }
 
 ##
+# @BlockDirtyBitmapMergeSource:
+#
+# @local: name of the bitmap, attached to the same node as target bitmap.
+#
+# @external: bitmap with specified node
+#
+# Since: 4.1
+##
+{ 'alternate': 'BlockDirtyBitmapMergeSource',
+  'data': { 'local': 'str',
+            'external': 'BlockDirtyBitmap' } }
+
+##
 # @BlockDirtyBitmapMerge:
 #
-# @node: name of device/node which the bitmap is tracking
+# @node: name of device/node which the @target bitmap is tracking
 #
 # @target: name of the destination dirty bitmap
 #
-# @bitmaps: name(s) of the source dirty bitmap(s)
+# @bitmaps: name(s) of the source dirty bitmap(s) at @node and/or fully
+#           specifed BlockDirtyBitmap elements. The latter are supported
+#           since 4.1.
 #
 # Since: 4.0
 ##
 { 'struct': 'BlockDirtyBitmapMerge',
-  'data': { 'node': 'str', 'target': 'str', 'bitmaps': ['str'] } }
+  'data': { 'node': 'str', 'target': 'str',
+            'bitmaps': ['BlockDirtyBitmapMergeSource'] } }
 
 ##
 # @block-dirty-bitmap-add:
diff --git a/tests/qemu-iotests/254 b/tests/qemu-iotests/254
new file mode 100755
index 0000000000..33cb80a512
--- /dev/null
+++ b/tests/qemu-iotests/254
@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+#
+# Test external snapshot with bitmap copying.
+#
+# Copyright (c) 2019 Virtuozzo International GmbH. All rights reserved.
+#
+# 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, see <http://www.gnu.org/licenses/>.
+#
+
+import iotests
+from iotests import qemu_img_create, file_path, log
+
+disk, top = file_path('disk', 'top')
+size = 1024 * 1024
+
+qemu_img_create('-f', iotests.imgfmt, disk, str(size))
+
+vm = iotests.VM().add_drive(disk, opts='node-name=base')
+vm.launch()
+
+vm.qmp_log('block-dirty-bitmap-add', node='drive0', name='bitmap0')
+
+vm.hmp_qemu_io('drive0', 'write 0 512K')
+
+vm.qmp_log('transaction', indent=2, actions=[
+    {'type': 'blockdev-snapshot-sync',
+     'data': {'device': 'drive0', 'snapshot-file': top,
+              'snapshot-node-name': 'snap'}},
+    {'type': 'block-dirty-bitmap-add',
+     'data': {'node': 'snap', 'name': 'bitmap0'}},
+    {'type': 'block-dirty-bitmap-merge',
+     'data': {'node': 'snap', 'target': 'bitmap0',
+              'bitmaps': [{'node': 'base', 'name': 'bitmap0'}]}}
+], filters=[iotests.filter_qmp_testfiles])
+
+result = vm.qmp('query-block')['return'][0]
+log("query-block: device = {}, node-name = {}, dirty-bitmaps:".format(
+    result['device'], result['inserted']['node-name']))
+log(result['dirty-bitmaps'], indent=2)
+
+vm.shutdown()
diff --git a/tests/qemu-iotests/254.out b/tests/qemu-iotests/254.out
new file mode 100644
index 0000000000..d7394cf002
--- /dev/null
+++ b/tests/qemu-iotests/254.out
@@ -0,0 +1,52 @@
+{"execute": "block-dirty-bitmap-add", "arguments": {"name": "bitmap0", "node": "drive0"}}
+{"return": {}}
+{
+  "execute": "transaction",
+  "arguments": {
+    "actions": [
+      {
+        "data": {
+          "device": "drive0",
+          "snapshot-file": "TEST_DIR/PID-top",
+          "snapshot-node-name": "snap"
+        },
+        "type": "blockdev-snapshot-sync"
+      },
+      {
+        "data": {
+          "name": "bitmap0",
+          "node": "snap"
+        },
+        "type": "block-dirty-bitmap-add"
+      },
+      {
+        "data": {
+          "bitmaps": [
+            {
+              "name": "bitmap0",
+              "node": "base"
+            }
+          ],
+          "node": "snap",
+          "target": "bitmap0"
+        },
+        "type": "block-dirty-bitmap-merge"
+      }
+    ]
+  }
+}
+{
+  "return": {}
+}
+query-block: device = drive0, node-name = snap, dirty-bitmaps:
+[
+  {
+    "busy": false,
+    "count": 524288,
+    "granularity": 65536,
+    "name": "bitmap0",
+    "persistent": false,
+    "recording": true,
+    "status": "active"
+  }
+]
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index 2c74deec00..859c4b5e9f 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -264,3 +264,4 @@
 249 rw auto quick
 252 rw auto backing quick
 253 rw auto quick
+254 rw auto backing quick