[Qemu-devel] [PATCH 1/3] block: Expose protocol-specific data to 'qemu-img info'

[Eric Blake <eblake@redhat.com>]

'qemu-img info' is useful for showing additional information
about an image - but sometimes the interesting information is
specific to the protocol rather than to the format layer.  Set
the groundwork for showing this information; further patches
will then enable specific pieces of information.

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 qapi/block-core.json | 6 +++++-
 block/qapi.c         | 7 +++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 91685be6c29..f28d5f5fc76 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -152,6 +152,9 @@
 # @format-specific: structure supplying additional format-specific
 # information (since 1.7)
 #
+# @protocol-specific: structure supplying additional protocol-specific
+# information (since 4.0)
+#
 # Since: 1.3
 #
 ##
@@ -162,7 +165,8 @@
            '*backing-filename': 'str', '*full-backing-filename': 'str',
            '*backing-filename-format': 'str', '*snapshots': ['SnapshotInfo'],
            '*backing-image': 'ImageInfo',
-           '*format-specific': 'ImageInfoSpecific' } }
+           '*format-specific': 'ImageInfoSpecific',
+           '*protocol-specific': 'ImageInfoSpecific' } }

 ##
 # @ImageCheck:
diff --git a/block/qapi.c b/block/qapi.c
index c66f949db83..a8d104ba8ce 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -284,6 +284,9 @@ void bdrv_query_image_info(BlockDriverState *bs,
     }
     info->format_specific     = bdrv_get_specific_info(bs);
     info->has_format_specific = info->format_specific != NULL;
+    info->protocol_specific =
+        bs->file ? bdrv_get_specific_info(bs->file->bs) : NULL;
+    info->has_protocol_specific = info->protocol_specific != NULL;

     backing_filename = bs->backing_file;
     if (backing_filename[0] != '\0') {
@@ -870,4 +873,8 @@ void bdrv_image_info_dump(fprintf_function func_fprintf, void *f,
         func_fprintf(f, "Format specific information:\n");
         bdrv_image_info_specific_dump(func_fprintf, f, info->format_specific);
     }
+    if (info->has_protocol_specific) {
+        func_fprintf(f, "Protocol specific information:\n");
+        bdrv_image_info_specific_dump(func_fprintf, f, info->protocol_specific);
+    }
 }
-- 
2.20.1