[07/11] block: Add bdrv_open_blockdev_ref_file()

Commit Message

Kevin Wolf Feb. 11, 2025, 9:43 p.m. UTC

This is the equivalent of bdrv_open_file_child() to be used in cases
where the caller is QAPI based and has a BlockdevRef rather than a
filename and an options QDict.

Signed-off-by: Kevin Wolf <[e-mail]>
---
 include/block/block-global-state.h |  4 ++++
 block.c                            | 30 +++++++++++++++++++++++++++---
 2 files changed, 31 insertions(+), 3 deletions(-)

Comments

Philippe Mathieu-Daudé Feb. 12, 2025, 7:43 a.m. UTC | #1

On 11/2/25 22:43, Kevin Wolf wrote:
> This is the equivalent of bdrv_open_file_child() to be used in cases
> where the caller is QAPI based and has a BlockdevRef rather than a
> filename and an options QDict.
> 
> Signed-off-by: Kevin Wolf <[e-mail]>
> ---
>   include/block/block-global-state.h |  4 ++++
>   block.c                            | 30 +++++++++++++++++++++++++++---
>   2 files changed, 31 insertions(+), 3 deletions(-)


> +BlockDriverState *bdrv_open_blockdev_ref_file(BlockdevRef *ref,
> +                                              BlockDriverState *parent,
> +                                              Error **errp)
> +{
> +    BdrvChildRole role;
> +
> +    /* commit_top and mirror_top don't use this function */
> +    assert(!parent->drv->filtered_child_is_backing);
> +    role = parent->drv->is_filter ?
> +        (BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY) : BDRV_CHILD_IMAGE;

Nitpicking style:

        role = parent->drv->is_filter
               ? (BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY)
               : BDRV_CHILD_IMAGE;

> +    return bdrv_open_blockdev_ref_common(ref, parent, &child_of_bds, role,
> +                                         true, errp);
> +}

Patch

diff --git a/include/block/block-global-state.h b/include/block/block-global-state.h
index 9be34b3c99..861e19cfe6 100644
--- a/include/block/block-global-state.h
+++ b/include/block/block-global-state.h
@@ -100,6 +100,10 @@  bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp);
 BlockDriverState * coroutine_fn no_co_wrapper
 bdrv_co_open_blockdev_ref(BlockdevRef *ref, Error **errp);
 
+BlockDriverState * no_coroutine_fn
+bdrv_open_blockdev_ref_file(BlockdevRef *ref, BlockDriverState *parent,
+                            Error **errp);
+
 int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd,
                         Error **errp);
 int GRAPH_WRLOCK
diff --git a/block.c b/block.c
index 0ece805e41..6315be79d8 100644
--- a/block.c
+++ b/block.c
@@ -3847,7 +3847,11 @@  int bdrv_open_file_child(const char *filename,
  * TODO Future callers may need to specify parent/child_class in order for
  * option inheritance to work. Existing callers use it for the root node.
  */
-BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp)
+static BlockDriverState * no_coroutine_fn
+bdrv_open_blockdev_ref_common(BlockdevRef *ref, BlockDriverState *parent,
+                              const BdrvChildClass *child_class,
+                              BdrvChildRole child_role, bool parse_filename,
+                              Error **errp)
 {
     BlockDriverState *bs = NULL;
     QObject *obj = NULL;
@@ -3880,14 +3884,34 @@  BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp)
 
     }
 
-    bs = bdrv_open_inherit(NULL, reference, qdict, 0, NULL, NULL, 0, false,
-                           errp);
+    bs = bdrv_open_inherit(NULL, reference, qdict, 0, parent, child_class,
+                           child_role, parse_filename, errp);
     obj = NULL;
     qobject_unref(obj);
     visit_free(v);
     return bs;
 }
 
+BlockDriverState *bdrv_open_blockdev_ref_file(BlockdevRef *ref,
+                                              BlockDriverState *parent,
+                                              Error **errp)
+{
+    BdrvChildRole role;
+
+    /* commit_top and mirror_top don't use this function */
+    assert(!parent->drv->filtered_child_is_backing);
+    role = parent->drv->is_filter ?
+        (BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY) : BDRV_CHILD_IMAGE;
+
+    return bdrv_open_blockdev_ref_common(ref, parent, &child_of_bds, role,
+                                         true, errp);
+}
+
+BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp)
+{
+    return bdrv_open_blockdev_ref_common(ref, NULL, NULL, 0, false, errp);
+}
+
 static BlockDriverState *bdrv_append_temp_snapshot(BlockDriverState *bs,
                                                    int flags,
                                                    QDict *snapshot_options,