To be reused soon for blockdev-replace functionality.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
---
 block.c                      | 13 +++++++++++++
 blockdev.c                   | 14 --------------
 include/block/block_int-io.h |  2 ++
 3 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/block.c b/block.c
index 468cf5e67d..f6292f459a 100644
--- a/block.c
+++ b/block.c
@@ -8174,6 +8174,19 @@ int bdrv_make_empty(BdrvChild *c, Error **errp)
     return 0;
 }
 
+BdrvChild *bdrv_find_child(BlockDriverState *parent_bs, const char *child_name)
+{
+    BdrvChild *child;
+
+    QLIST_FOREACH(child, &parent_bs->children, next) {
+        if (strcmp(child->name, child_name) == 0) {
+            return child;
+        }
+    }
+
+    return NULL;
+}
+
 /*
  * Return the child that @bs acts as an overlay for, and from which data may be
  * copied in COW or COR operations.  Usually this is the backing file.
diff --git a/blockdev.c b/blockdev.c
index 835064ed03..ba7e90b06e 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -3452,20 +3452,6 @@ void qmp_blockdev_del(const char *node_name, Error **errp)
     bdrv_unref(bs);
 }
 
-static BdrvChild * GRAPH_RDLOCK
-bdrv_find_child(BlockDriverState *parent_bs, const char *child_name)
-{
-    BdrvChild *child;
-
-    QLIST_FOREACH(child, &parent_bs->children, next) {
-        if (strcmp(child->name, child_name) == 0) {
-            return child;
-        }
-    }
-
-    return NULL;
-}
-
 void qmp_x_blockdev_change(const char *parent, const char *child,
                            const char *node, Error **errp)
 {
diff --git a/include/block/block_int-io.h b/include/block/block_int-io.h
index 4a7cf2b4fd..11ed4aa927 100644
--- a/include/block/block_int-io.h
+++ b/include/block/block_int-io.h
@@ -130,6 +130,8 @@ bdrv_co_refresh_total_sectors(BlockDriverState *bs, int64_t hint);
 int co_wrapper_mixed_bdrv_rdlock
 bdrv_refresh_total_sectors(BlockDriverState *bs, int64_t hint);
 
+BdrvChild * GRAPH_RDLOCK
+bdrv_find_child(BlockDriverState *parent_bs, const char *child_name);
 BdrvChild * GRAPH_RDLOCK bdrv_cow_child(BlockDriverState *bs);
 BdrvChild * GRAPH_RDLOCK bdrv_filter_child(BlockDriverState *bs);
 BdrvChild * GRAPH_RDLOCK bdrv_filter_or_cow_child(BlockDriverState *bs);
-- 
2.34.1