commit: Add filter-node-name to block-commit

Management tools need to be able to know about every node in the graph
and need a way to address them. Changing the graph structure was okay
because libvirt doesn't really manage the node level yet, but future
libvirt versions need to deal with both new and old version of qemu.

This new option to blockdev-commit allows the client to set a node-name
for the automatically inserted filter driver, and at the same time
serves as a witness for a future libvirt that this version of qemu does
automatically insert a filter driver.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>

1 files changed, 10 insertions, 3 deletions

diff --git a/include/block/block_int.h b/include/block/block_int.h
index 563b30c3ee..a57c0bfb55 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -780,13 +780,16 @@ void stream_start(const char *job_id, BlockDriverState *bs,
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @on_error: The action to take upon error.
  * @backing_file_str: String to use as the backing file in @top's overlay
+ * @filter_node_name: The node name that should be assigned to the filter
+ * driver that the commit job inserts into the graph above @top. NULL means
+ * that a node name should be autogenerated.
  * @errp: Error object.
  *
  */
 void commit_start(const char *job_id, BlockDriverState *bs,
                   BlockDriverState *base, BlockDriverState *top, int64_t speed,
                   BlockdevOnError on_error, const char *backing_file_str,
-                  Error **errp);
+                  const char *filter_node_name, Error **errp);
 /**
  * commit_active_start:
  * @job_id: The id of the newly-created job, or %NULL to use the
@@ -797,6 +800,9 @@ void commit_start(const char *job_id, BlockDriverState *bs,
  *                  See @BlockJobCreateFlags
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @on_error: The action to take upon error.
+ * @filter_node_name: The node name that should be assigned to the filter
+ * driver that the commit job inserts into the graph above @bs. NULL means that
+ * a node name should be autogenerated.
  * @cb: Completion function for the job.
  * @opaque: Opaque pointer value passed to @cb.
  * @errp: Error object.
@@ -806,8 +812,9 @@ void commit_start(const char *job_id, BlockDriverState *bs,
 void commit_active_start(const char *job_id, BlockDriverState *bs,
                          BlockDriverState *base, int creation_flags,
                          int64_t speed, BlockdevOnError on_error,
-                         BlockCompletionFunc *cb,
-                         void *opaque, Error **errp, bool auto_complete);
+                         const char *filter_node_name,
+                         BlockCompletionFunc *cb, void *opaque, Error **errp,
+                         bool auto_complete);
 /*
  * mirror_start:
  * @job_id: The id of the newly-created job, or %NULL to use the