qemu-img: Use BlockNodeInfo

qemu-img info never uses ImageInfo's backing-image field, because it
opens the backing chain one by one with BDRV_O_NO_BACKING, and prints
all backing chain nodes' information consecutively.  Use BlockNodeInfo
to make it clear that we only print information about a single node, and
that we are not using the backing-image field.

Notably, bdrv_image_info_dump() does not evaluate the backing-image
field, so we can easily make it take a BlockNodeInfo pointer (and
consequentially rename it to bdrv_node_info_dump()).  It makes more
sense this way, because again, the interface now makes it syntactically
clear that backing-image is ignored by this function.

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220620162704.80987-6-hreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/monitor/block-hmp-cmds.c

@@ -725,7 +725,7 @@ static void print_block_info(Monitor *mon, BlockInfo *info,
         monitor_printf(mon, "\nImages:\n");
         image_info = inserted->image;
         while (1) {
-                bdrv_image_info_dump(image_info);
+            bdrv_node_info_dump(qapi_ImageInfo_base(image_info));
             if (image_info->backing_image) {
                 image_info = image_info->backing_image;
             } else {

block/qapi.c

@@ -848,7 +848,7 @@ void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec,
     visit_free(v);
 }
 
-void bdrv_image_info_dump(ImageInfo *info)
+void bdrv_node_info_dump(BlockNodeInfo *info)
 {
     char *size_buf, *dsize_buf;
     if (!info->has_actual_size) {

include/block/qapi.h

@@ -45,5 +45,5 @@ void bdrv_query_image_info(BlockDriverState *bs,
 void bdrv_snapshot_dump(QEMUSnapshotInfo *sn);
 void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec,
                                    const char *prefix);
-void bdrv_image_info_dump(ImageInfo *info);
+void bdrv_node_info_dump(BlockNodeInfo *info);
 #endif

qapi/block-core.json

@@ -5796,9 +5796,9 @@
 ##
 # @DummyBlockCoreForceArrays:
 #
-# Not used by QMP; hack to let us use ImageInfoList internally
+# Not used by QMP; hack to let us use BlockNodeInfoList internally
 #
 # Since: 8.0
 ##
 { 'struct': 'DummyBlockCoreForceArrays',
-  'data': { 'unused-image-info': ['ImageInfo'] } }
+  'data': { 'unused-block-node-info': ['BlockNodeInfo'] } }

qemu-img.c

@@ -2817,13 +2817,13 @@ static void dump_snapshots(BlockDriverState *bs)
     g_free(sn_tab);
 }
 
-static void dump_json_image_info_list(ImageInfoList *list)
+static void dump_json_block_node_info_list(BlockNodeInfoList *list)
 {
     GString *str;
     QObject *obj;
     Visitor *v = qobject_output_visitor_new(&obj);
 
-    visit_type_ImageInfoList(v, NULL, &list, &error_abort);
+    visit_type_BlockNodeInfoList(v, NULL, &list, &error_abort);
     visit_complete(v, &obj);
     str = qobject_to_json_pretty(obj, true);
     assert(str != NULL);
@@ -2833,13 +2833,13 @@ static void dump_json_image_info_list(ImageInfoList *list)
     g_string_free(str, true);
 }
 
-static void dump_json_image_info(ImageInfo *info)
+static void dump_json_block_node_info(BlockNodeInfo *info)
 {
     GString *str;
     QObject *obj;
     Visitor *v = qobject_output_visitor_new(&obj);
 
-    visit_type_ImageInfo(v, NULL, &info, &error_abort);
+    visit_type_BlockNodeInfo(v, NULL, &info, &error_abort);
     visit_complete(v, &obj);
     str = qobject_to_json_pretty(obj, true);
     assert(str != NULL);
@@ -2849,9 +2849,9 @@ static void dump_json_image_info(ImageInfo *info)
     g_string_free(str, true);
 }
 
-static void dump_human_image_info_list(ImageInfoList *list)
+static void dump_human_image_info_list(BlockNodeInfoList *list)
 {
-    ImageInfoList *elem;
+    BlockNodeInfoList *elem;
     bool delim = false;
 
     for (elem = list; elem; elem = elem->next) {
@@ -2860,7 +2860,7 @@ static void dump_human_image_info_list(ImageInfoList *list)
         }
         delim = true;
 
-        bdrv_image_info_dump(elem->value);
+        bdrv_node_info_dump(elem->value);
     }
 }
 
@@ -2870,24 +2870,24 @@ static gboolean str_equal_func(gconstpointer a, gconstpointer b)
 }
 
 /**
- * Open an image file chain and return an ImageInfoList
+ * Open an image file chain and return an BlockNodeInfoList
  *
  * @filename: topmost image filename
  * @fmt: topmost image format (may be NULL to autodetect)
  * @chain: true  - enumerate entire backing file chain
  *         false - only topmost image file
  *
- * Returns a list of ImageInfo objects or NULL if there was an error opening an
- * image file.  If there was an error a message will have been printed to
- * stderr.
+ * Returns a list of BlockNodeInfo objects or NULL if there was an error
+ * opening an image file.  If there was an error a message will have been
+ * printed to stderr.
  */
-static ImageInfoList *collect_image_info_list(bool image_opts,
-                                              const char *filename,
-                                              const char *fmt,
-                                              bool chain, bool force_share)
+static BlockNodeInfoList *collect_image_info_list(bool image_opts,
+                                                  const char *filename,
+                                                  const char *fmt,
+                                                  bool chain, bool force_share)
 {
-    ImageInfoList *head = NULL;
-    ImageInfoList **tail = &head;
+    BlockNodeInfoList *head = NULL;
+    BlockNodeInfoList **tail = &head;
     GHashTable *filenames;
     Error *err = NULL;
 
@@ -2896,7 +2896,7 @@ static ImageInfoList *collect_image_info_list(bool image_opts,
     while (filename) {
         BlockBackend *blk;
         BlockDriverState *bs;
-        ImageInfo *info;
+        BlockNodeInfo *info;
 
         if (g_hash_table_lookup_extended(filenames, filename, NULL, NULL)) {
             error_report("Backing file '%s' creates an infinite loop.",
@@ -2913,7 +2913,7 @@ static ImageInfoList *collect_image_info_list(bool image_opts,
         }
         bs = blk_bs(blk);
 
-        bdrv_query_image_info(bs, &info, &err);
+        bdrv_query_block_node_info(bs, &info, &err);
         if (err) {
             error_report_err(err);
             blk_unref(blk);
@@ -2946,7 +2946,7 @@ static ImageInfoList *collect_image_info_list(bool image_opts,
     return head;
 
 err:
-    qapi_free_ImageInfoList(head);
+    qapi_free_BlockNodeInfoList(head);
     g_hash_table_destroy(filenames);
     return NULL;
 }
@@ -2957,7 +2957,7 @@ static int img_info(int argc, char **argv)
     OutputFormat output_format = OFORMAT_HUMAN;
     bool chain = false;
     const char *filename, *fmt, *output;
-    ImageInfoList *list;
+    BlockNodeInfoList *list;
     bool image_opts = false;
     bool force_share = false;
 
@@ -3036,14 +3036,14 @@ static int img_info(int argc, char **argv)
         break;
     case OFORMAT_JSON:
         if (chain) {
-            dump_json_image_info_list(list);
+            dump_json_block_node_info_list(list);
         } else {
-            dump_json_image_info(list->value);
+            dump_json_block_node_info(list->value);
         }
         break;
     }
 
-    qapi_free_ImageInfoList(list);
+    qapi_free_BlockNodeInfoList(list);
     return 0;
 }