[PATCH 1/5] block: implement bdrv_new_open_driver_opts()

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

Add version of bdrv_new_open_driver() that supports QDict options.
We'll use it in further commit.

Simply add one more argument to bdrv_new_open_driver() is worse, as
there are too many invocations of bdrv_new_open_driver() to update
then.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Suggested-by: Kevin Wolf <kwolf@redhat.com>
---
 include/block/block.h |  4 ++++
 block.c               | 25 +++++++++++++++++++++----
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/include/block/block.h b/include/block/block.h
index 740038a892..24b773e69c 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -383,6 +383,10 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options,
                            const char *bdref_key, Error **errp);
 BlockDriverState *bdrv_open(const char *filename, const char *reference,
                             QDict *options, int flags, Error **errp);
+BlockDriverState *bdrv_new_open_driver_opts(BlockDriver *drv,
+                                            const char *node_name,
+                                            QDict *options, int flags,
+                                            Error **errp);
 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name,
                                        int flags, Error **errp);
 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
diff --git a/block.c b/block.c
index 5ce08a79fd..917fb7faca 100644
--- a/block.c
+++ b/block.c
@@ -1604,16 +1604,26 @@ open_failed:
     return ret;
 }
 
-BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name,
-                                       int flags, Error **errp)
+/*
+ * Create and open a block node.
+ *
+ * @options is a QDict of options to pass to the block drivers, or NULL for an
+ * empty set of options. The reference to the QDict belongs to the block layer
+ * after the call (even on failure), so if the caller intends to reuse the
+ * dictionary, it needs to use qobject_ref() before calling bdrv_open.
+ */
+BlockDriverState *bdrv_new_open_driver_opts(BlockDriver *drv,
+                                            const char *node_name,
+                                            QDict *options, int flags,
+                                            Error **errp)
 {
     BlockDriverState *bs;
     int ret;
 
     bs = bdrv_new();
     bs->open_flags = flags;
-    bs->explicit_options = qdict_new();
-    bs->options = qdict_new();
+    bs->options = options ?: qdict_new();
+    bs->explicit_options = qdict_clone_shallow(bs->options);
     bs->opaque = NULL;
 
     update_options_from_flags(bs->options, flags);
@@ -1631,6 +1641,13 @@ BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name,
     return bs;
 }
 
+/* Create and open a block node. */
+BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name,
+                                       int flags, Error **errp)
+{
+    return bdrv_new_open_driver_opts(drv, node_name, NULL, flags, errp);
+}
+
 QemuOptsList bdrv_runtime_opts = {
     .name = "bdrv_common",
     .head = QTAILQ_HEAD_INITIALIZER(bdrv_runtime_opts.head),
-- 
2.29.2