1 files changed, 55 insertions, 19 deletions

diff --git a/block/qapi.c b/block/qapi.c
index afd9f3b4a7..f423ece98c 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -47,7 +47,7 @@ BlockDeviceInfo *bdrv_block_device_info(BlockBackend *blk,
                                         Error **errp)
 {
     ImageInfo **p_image_info;
-    BlockDriverState *bs0;
+    BlockDriverState *bs0, *backing;
     BlockDeviceInfo *info;
 
     if (!bs->drv) {
@@ -76,9 +76,10 @@ BlockDeviceInfo *bdrv_block_device_info(BlockBackend *blk,
         info->node_name = g_strdup(bs->node_name);
     }
 
-    if (bs->backing_file[0]) {
+    backing = bdrv_cow_bs(bs);
+    if (backing) {
         info->has_backing_file = true;
-        info->backing_file = g_strdup(bs->backing_file);
+        info->backing_file = g_strdup(backing->filename);
     }
 
     if (!QLIST_EMPTY(&bs->dirty_bitmaps)) {
@@ -163,9 +164,13 @@ BlockDeviceInfo *bdrv_block_device_info(BlockBackend *blk,
             break;
         }
 
-        if (bs0->drv && bs0->backing) {
+        if (bs0->drv && bdrv_filter_or_cow_child(bs0)) {
+            /*
+             * Put any filtered child here (for backwards compatibility to when
+             * we put bs0->backing here, which might be any filtered child).
+             */
             info->backing_file_depth++;
-            bs0 = bs0->backing->bs;
+            bs0 = bdrv_filter_or_cow_bs(bs0);
             (*p_image_info)->has_backing_image = true;
             p_image_info = &((*p_image_info)->backing_image);
         } else {
@@ -174,9 +179,8 @@ BlockDeviceInfo *bdrv_block_device_info(BlockBackend *blk,
 
         /* Skip automatically inserted nodes that the user isn't aware of for
          * query-block (blk != NULL), but not for query-named-block-nodes */
-        while (blk && bs0->drv && bs0->implicit) {
-            bs0 = backing_bs(bs0);
-            assert(bs0);
+        if (blk) {
+            bs0 = bdrv_skip_implicit_filters(bs0);
         }
     }
 
@@ -288,7 +292,7 @@ void bdrv_query_image_info(BlockDriverState *bs,
     info->virtual_size    = size;
     info->actual_size     = bdrv_get_allocated_file_size(bs);
     info->has_actual_size = info->actual_size >= 0;
-    if (bdrv_is_encrypted(bs)) {
+    if (bs->encrypted) {
         info->encrypted = true;
         info->has_encrypted = true;
     }
@@ -311,6 +315,7 @@ void bdrv_query_image_info(BlockDriverState *bs,
     backing_filename = bs->backing_file;
     if (backing_filename[0] != '\0') {
         char *backing_filename2;
+
         info->backing_filename = g_strdup(backing_filename);
         info->has_backing_filename = true;
         backing_filename2 = bdrv_get_full_backing_filename(bs, NULL);
@@ -362,9 +367,7 @@ static void bdrv_query_info(BlockBackend *blk, BlockInfo **p_info,
     char *qdev;
 
     /* Skip automatically inserted nodes that the user isn't aware of */
-    while (bs && bs->drv && bs->implicit) {
-        bs = backing_bs(bs);
-    }
+    bs = bdrv_skip_implicit_filters(bs);
 
     info->device = g_strdup(blk_name(blk));
     info->type = g_strdup("unknown");
@@ -526,6 +529,8 @@ static void bdrv_query_blk_stats(BlockDeviceStats *ds, BlockBackend *blk)
 static BlockStats *bdrv_query_bds_stats(BlockDriverState *bs,
                                         bool blk_level)
 {
+    BdrvChild *parent_child;
+    BlockDriverState *filter_or_cow_bs;
     BlockStats *s = NULL;
 
     s = g_malloc0(sizeof(*s));
@@ -538,9 +543,8 @@ static BlockStats *bdrv_query_bds_stats(BlockDriverState *bs,
     /* Skip automatically inserted nodes that the user isn't aware of in
      * a BlockBackend-level command. Stay at the exact node for a node-level
      * command. */
-    while (blk_level && bs->drv && bs->implicit) {
-        bs = backing_bs(bs);
-        assert(bs);
+    if (blk_level) {
+        bs = bdrv_skip_implicit_filters(bs);
     }
 
     if (bdrv_get_node_name(bs)[0]) {
@@ -555,14 +559,46 @@ static BlockStats *bdrv_query_bds_stats(BlockDriverState *bs,
         s->has_driver_specific = true;
     }
 
-    if (bs->file) {
+    parent_child = bdrv_primary_child(bs);
+    if (!parent_child ||
+        !(parent_child->role & (BDRV_CHILD_DATA | BDRV_CHILD_FILTERED)))
+    {
+        BdrvChild *c;
+
+        /*
+         * Look for a unique data-storing child.  We do not need to look for
+         * filtered children, as there would be only one and it would have been
+         * the primary child.
+         */
+        parent_child = NULL;
+        QLIST_FOREACH(c, &bs->children, next) {
+            if (c->role & BDRV_CHILD_DATA) {
+                if (parent_child) {
+                    /*
+                     * There are multiple data-storing children and we cannot
+                     * choose between them.
+                     */
+                    parent_child = NULL;
+                    break;
+                }
+                parent_child = c;
+            }
+        }
+    }
+    if (parent_child) {
         s->has_parent = true;
-        s->parent = bdrv_query_bds_stats(bs->file->bs, blk_level);
+        s->parent = bdrv_query_bds_stats(parent_child->bs, blk_level);
     }
 
-    if (blk_level && bs->backing) {
+    filter_or_cow_bs = bdrv_filter_or_cow_bs(bs);
+    if (blk_level && filter_or_cow_bs) {
+        /*
+         * Put any filtered or COW child here (for backwards
+         * compatibility to when we put bs0->backing here, which might
+         * be either)
+         */
         s->has_backing = true;
-        s->backing = bdrv_query_bds_stats(bs->backing->bs, blk_level);
+        s->backing = bdrv_query_bds_stats(filter_or_cow_bs, blk_level);
     }
 
     return s;