[Qemu-devel] [PATCH 16/21] qmp: add persistent flag to block-dirty-bitmap-add

[Vladimir Sementsov-Ogievskiy]

Add optional 'persistent' flag to qmp command block-dirty-bitmap-add.
Default is false.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
---
 blockdev.c            | 17 ++++++++++++++++-
 docs/qmp-commands.txt |  3 +++
 qapi/block-core.json  |  7 ++++++-
 3 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/blockdev.c b/blockdev.c
index ded1326..de372ed 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1961,6 +1961,7 @@ static void block_dirty_bitmap_add_prepare(BlkActionState 
*common,
     /* AIO context taken and released within qmp_block_dirty_bitmap_add */
     qmp_block_dirty_bitmap_add(action->node, action->name,
                                action->has_granularity, action->granularity,
+                               action->has_persistent, action->persistent,
                                &local_err);
 
     if (!local_err) {
@@ -2688,10 +2689,12 @@ out:
 
 void qmp_block_dirty_bitmap_add(const char *node, const char *name,
                                 bool has_granularity, uint32_t granularity,
+                                bool has_persistent, bool persistent,
                                 Error **errp)
 {
     AioContext *aio_context;
     BlockDriverState *bs;
+    BdrvDirtyBitmap *bitmap;
 
     if (!name || name[0] == '\0') {
         error_setg(errp, "Bitmap name cannot be empty");
@@ -2717,7 +2720,19 @@ void qmp_block_dirty_bitmap_add(const char *node, const 
char *name,
         granularity = bdrv_get_default_bitmap_granularity(bs);
     }
 
-    bdrv_create_dirty_bitmap(bs, granularity, name, errp);
+    if (!has_persistent) {
+        persistent = false;
+    }
+
+    if (persistent &&
+            !bdrv_can_store_dirty_bitmap(bs, name, granularity, errp)) {
+        goto out;
+    }
+
+    bitmap = bdrv_create_dirty_bitmap(bs, granularity, name, errp);
+    if (bitmap != NULL) {
+        bdrv_dirty_bitmap_set_persistance(bitmap, persistent);
+    }
 
  out:
     aio_context_release(aio_context);
diff --git a/docs/qmp-commands.txt b/docs/qmp-commands.txt
index 0fde435..bfb5df6 100644
--- a/docs/qmp-commands.txt
+++ b/docs/qmp-commands.txt
@@ -1005,6 +1005,9 @@ Arguments:
 - "node": device/node on which to create dirty bitmap (json-string)
 - "name": name of the new dirty bitmap (json-string)
 - "granularity": granularity to track writes with (int, optional)
+- "persistent": bitmap will be saved to the corresponding block device image
+                file on its close. For now only Qcow2 disks support persistent
+                bitmaps. (json-bool, optional, default false) (Since 2.8)
 
 Example:
 
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 3592a9d..134e77e 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1231,10 +1231,15 @@
 # @granularity: #optional the bitmap granularity, default is 64k for
 #               block-dirty-bitmap-add
 #
+# @persistent: #optional the bitmap is persistent, i.e. it will be saved to the
+#              corresponding block device image file on its close. Default is
+#              false. (Since 2.8)
+#
 # Since 2.4
 ##
 { 'struct': 'BlockDirtyBitmapAdd',
-  'data': { 'node': 'str', 'name': 'str', '*granularity': 'uint32' } }
+  'data': { 'node': 'str', 'name': 'str', '*granularity': 'uint32',
+            '*persistent': 'bool' } }
 
 ##
 # @block-dirty-bitmap-add
-- 
1.8.3.1