[Qemu-devel] [PATCH 5/9] qmp: add qmp cmd block-dirty-bitmap-copy

[John Snow]

Add the ability to copy one bitmap to a new bitmap.

Signed-off-by: John Snow <address@hidden>
---
 blockdev.c           | 22 ++++++++++++++++++++++
 qapi/block-core.json | 16 ++++++++++++++++
 qmp-commands.hx      | 30 ++++++++++++++++++++++++++++++
 3 files changed, 68 insertions(+)

diff --git a/blockdev.c b/blockdev.c
index 905bf84..9233bcd 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2445,6 +2445,28 @@ void qmp_block_dirty_bitmap_add(const char *node, const 
char *name,
     aio_context_release(aio_context);
 }
 
+void qmp_block_dirty_bitmap_copy(const char *node, const char *source,
+                                 const char *dest, Error **errp)
+{
+    AioContext *aio_context;
+    BlockDriverState *bs;
+    BdrvDirtyBitmap *bitmap;
+
+    if (!dest || dest[0] == '\0') {
+        error_setg(errp, "Bitmap name cannot be empty");
+        return;
+    }
+
+    bitmap = block_dirty_bitmap_lookup(node, source, &bs, &aio_context, errp);
+    if (!bitmap || !bs) {
+        return;
+    }
+
+    /* Duplicate name checking is left to bdrv_copy_dirty_bitmap */
+    bdrv_copy_dirty_bitmap(bs, bitmap, dest, errp);
+    aio_context_release(aio_context);
+}
+
 void qmp_block_dirty_bitmap_remove(const char *node, const char *name,
                                    Error **errp)
 {
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 6bed205..92c9e53 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1043,6 +1043,22 @@
   'data': 'BlockDirtyBitmapAdd' }
 
 ##
+# @block-dirty-bitmap-copy
+#
+# Copy a dirty bitmap into a new dirty bitmap
+#
+# Returns: nothing on success
+#          If @node is not a valid block device or node, DeviceNotFound
+#          If @source is not a valid bitmap, GenericError
+#          if @dest is not a valid bitmap name, GenericError
+#          if @dest is already taken, GenericError
+#
+# Since 2.4
+##
+{ 'command': 'block-dirty-bitmap-copy',
+  'data': 'BlockDirtyBitmapCopy' }
+
+##
 # @block-dirty-bitmap-remove
 #
 # Remove a dirty bitmap on the node
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 1e74188..9818b3f 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1347,6 +1347,36 @@ Example:
 EQMP
 
     {
+        .name       = "block-dirty-bitmap-copy",
+        .args_type  = "node:B,source:s,dest:s",
+        .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_copy,
+    },
+
+SQMP
+
+block-dirty-bitmap-copy
+-----------------------
+Since 2.4
+
+Copy a dirty bitmap from 'source' to a new bitmap 'dest', then start tracking
+new writes immediately.
+
+Arguments:
+
+- "node": device/node on which to create dirty bitmap (json-string)
+- "source": name of the dirty bitmap to be copied (json-string)
+- "dest": name of the dirty bitmap to be copied (json-string)
+
+Example:
+
+-> { "execute": "block-dirty-bitmap-copy", "arguments": { "node": "drive0",
+                                                          "source": "bitmap0",
+                                                          "dest": "bitmap1" } }
+<- { "return": {} }
+
+EQMP
+
+    {
         .name       = "block-dirty-bitmap-remove",
         .args_type  = "node:B,name:s",
         .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_remove,
-- 
2.1.0