block: Fix error handling in bdrv_replace_in_backing_chain()

When adding an Error parameter, bdrv_replace_in_backing_chain() would
become nothing more than a wrapper around change_parent_backing_link().
So make the latter public, renamed as bdrv_replace_node(), and remove
bdrv_replace_in_backing_chain().

Most of the callers just remove a node from the graph that they just
inserted, so they can use &error_abort, but completion of a mirror job
with 'replaces' set can actually fail.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/include/block/block.h b/include/block/block.h
index c7c4a3ac3a..5149260827 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -238,8 +238,8 @@ int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp);
 BlockDriverState *bdrv_new(void);
 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top,
                  Error **errp);
-void bdrv_replace_in_backing_chain(BlockDriverState *old,
-                                   BlockDriverState *new);
+void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to,
+                       Error **errp);
 
 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough);
 int bdrv_parse_discard_flags(const char *mode, int *flags);