block: Avoid bs->blk in bdrv_next()

We need to introduce a separate BdrvNextIterator struct that can keep
more state than just the current BDS in order to avoid using the bs->blk
pointer.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/qmp.c b/qmp.c
index e784a67631..8f8ae3a79d 100644
--- a/qmp.c
+++ b/qmp.c
@@ -181,6 +181,7 @@ void qmp_cont(Error **errp)
     Error *local_err = NULL;
     BlockBackend *blk;
     BlockDriverState *bs;
+    BdrvNextIterator *it;
 
     /* if there is a dump in background, we should wait until the dump
      * finished */
@@ -199,7 +200,9 @@ void qmp_cont(Error **errp)
     for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
         blk_iostatus_reset(blk);
     }
-    for (bs = bdrv_next(NULL); bs; bs = bdrv_next(bs)) {
+
+    it = NULL;
+    while ((it = bdrv_next(it, &bs))) {
         bdrv_add_key(bs, NULL, &local_err);
         if (local_err) {
             error_propagate(errp, local_err);