block/dirty-bitmap: Clean up local variable shadowing

Local variables shadowing other local variables or parameters make the
code needlessly hard to understand.  Tracked down with -Wshadow=local.
Clean up: rename both the pair of parameters and the pair of local
variables.  While there, move the local variables to function scope.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230921121312.1301864-5-armbru@redhat.com>

block/monitor/bitmap-qmp-cmds.c

@@ -258,37 +258,38 @@ void qmp_block_dirty_bitmap_disable(const char *node, const char *name,
     bdrv_disable_dirty_bitmap(bitmap);
 }
 
-BdrvDirtyBitmap *block_dirty_bitmap_merge(const char *node, const char *target,
+BdrvDirtyBitmap *block_dirty_bitmap_merge(const char *dst_node,
+                                          const char *dst_bitmap,
                                           BlockDirtyBitmapOrStrList *bms,
                                           HBitmap **backup, Error **errp)
 {
     BlockDriverState *bs;
     BdrvDirtyBitmap *dst, *src;
     BlockDirtyBitmapOrStrList *lst;
+    const char *src_node, *src_bitmap;
     HBitmap *local_backup = NULL;
 
     GLOBAL_STATE_CODE();
 
-    dst = block_dirty_bitmap_lookup(node, target, &bs, errp);
+    dst = block_dirty_bitmap_lookup(dst_node, dst_bitmap, &bs, errp);
     if (!dst) {
         return NULL;
     }
 
     for (lst = bms; lst; lst = lst->next) {
         switch (lst->value->type) {
-            const char *name, *node;
         case QTYPE_QSTRING:
-            name = lst->value->u.local;
-            src = bdrv_find_dirty_bitmap(bs, name);
+            src_bitmap = lst->value->u.local;
+            src = bdrv_find_dirty_bitmap(bs, src_bitmap);
             if (!src) {
-                error_setg(errp, "Dirty bitmap '%s' not found", name);
+                error_setg(errp, "Dirty bitmap '%s' not found", src_bitmap);
                 goto fail;
             }
             break;
         case QTYPE_QDICT:
-            node = lst->value->u.external.node;
-            name = lst->value->u.external.name;
-            src = block_dirty_bitmap_lookup(node, name, NULL, errp);
+            src_node = lst->value->u.external.node;
+            src_bitmap = lst->value->u.external.name;
+            src = block_dirty_bitmap_lookup(src_node, src_bitmap, NULL, errp);
             if (!src) {
                 goto fail;
             }

block/qcow2-bitmap.c

@@ -1555,7 +1555,6 @@ bool qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
     FOR_EACH_DIRTY_BITMAP(bs, bitmap) {
         const char *name = bdrv_dirty_bitmap_name(bitmap);
         uint32_t granularity = bdrv_dirty_bitmap_granularity(bitmap);
-        Qcow2Bitmap *bm;
 
         if (!bdrv_dirty_bitmap_get_persistence(bitmap) ||
             bdrv_dirty_bitmap_inconsistent(bitmap)) {
@@ -1625,7 +1624,7 @@ bool qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
 
     /* allocate clusters and store bitmaps */
     QSIMPLEQ_FOREACH(bm, bm_list, entry) {
-        BdrvDirtyBitmap *bitmap = bm->dirty_bitmap;
+        bitmap = bm->dirty_bitmap;
 
         if (bitmap == NULL || bdrv_dirty_bitmap_readonly(bitmap)) {
             continue;