1 files changed, 37 insertions, 7 deletions

diff --git a/block.c b/block.c
index 1bdb9c679d..957630b1c5 100644
--- a/block.c
+++ b/block.c
@@ -600,7 +600,7 @@ static int bdrv_create_file_fallback(const char *filename, BlockDriver *drv,
                                      QemuOpts *opts, Error **errp)
 {
     BlockBackend *blk;
-    QDict *options = qdict_new();
+    QDict *options;
     int64_t size = 0;
     char *buf = NULL;
     PreallocMode prealloc;
@@ -623,6 +623,7 @@ static int bdrv_create_file_fallback(const char *filename, BlockDriver *drv,
         return -ENOTSUP;
     }
 
+    options = qdict_new();
     qdict_put_str(options, "driver", drv->format_name);
 
     blk = blk_new_open(filename, NULL, options,
@@ -3694,6 +3695,15 @@ cleanup_perm:
             }
         }
     }
+
+    if (ret == 0) {
+        QTAILQ_FOREACH_REVERSE(bs_entry, bs_queue, entry) {
+            BlockDriverState *bs = bs_entry->state.bs;
+
+            if (bs->drv->bdrv_reopen_commit_post)
+                bs->drv->bdrv_reopen_commit_post(&bs_entry->state);
+        }
+    }
 cleanup:
     QTAILQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) {
         if (ret) {
@@ -3777,6 +3787,29 @@ static void bdrv_reopen_perm(BlockReopenQueue *q, BlockDriverState *bs,
     *shared = cumulative_shared_perms;
 }
 
+static bool bdrv_reopen_can_attach(BlockDriverState *parent,
+                                   BdrvChild *child,
+                                   BlockDriverState *new_child,
+                                   Error **errp)
+{
+    AioContext *parent_ctx = bdrv_get_aio_context(parent);
+    AioContext *child_ctx = bdrv_get_aio_context(new_child);
+    GSList *ignore;
+    bool ret;
+
+    ignore = g_slist_prepend(NULL, child);
+    ret = bdrv_can_set_aio_context(new_child, parent_ctx, &ignore, NULL);
+    g_slist_free(ignore);
+    if (ret) {
+        return ret;
+    }
+
+    ignore = g_slist_prepend(NULL, child);
+    ret = bdrv_can_set_aio_context(parent, child_ctx, &ignore, errp);
+    g_slist_free(ignore);
+    return ret;
+}
+
 /*
  * Take a BDRVReopenState and check if the value of 'backing' in the
  * reopen_state->options QDict is valid or not.
@@ -3828,14 +3861,11 @@ static int bdrv_reopen_parse_backing(BDRVReopenState *reopen_state,
     }
 
     /*
-     * TODO: before removing the x- prefix from x-blockdev-reopen we
-     * should move the new backing file into the right AioContext
-     * instead of returning an error.
+     * Check AioContext compatibility so that the bdrv_set_backing_hd() call in
+     * bdrv_reopen_commit() won't fail.
      */
     if (new_backing_bs) {
-        if (bdrv_get_aio_context(new_backing_bs) != bdrv_get_aio_context(bs)) {
-            error_setg(errp, "Cannot use a new backing file "
-                       "with a different AioContext");
+        if (!bdrv_reopen_can_attach(bs, bs->backing, new_backing_bs, errp)) {
             return -EINVAL;
         }
     }