aboutsummaryrefslogtreecommitdiff
path: root/block.c
diff options
context:
space:
mode:
Diffstat (limited to 'block.c')
-rw-r--r--block.c52
1 files changed, 45 insertions, 7 deletions
diff --git a/block.c b/block.c
index 3cd281dbcc..9698f2ad44 100644
--- a/block.c
+++ b/block.c
@@ -3107,9 +3107,21 @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue,
bs_entry->state.perm = UINT64_MAX;
bs_entry->state.shared_perm = 0;
+ /*
+ * If keep_old_opts is false then it means that unspecified
+ * options must be reset to their original value. We don't allow
+ * resetting 'backing' but we need to know if the option is
+ * missing in order to decide if we have to return an error.
+ */
+ if (!keep_old_opts) {
+ bs_entry->state.backing_missing =
+ !qdict_haskey(options, "backing") &&
+ !qdict_haskey(options, "backing.driver");
+ }
+
QLIST_FOREACH(child, &bs->children, next) {
- QDict *new_child_options;
- char *child_key_dot;
+ QDict *new_child_options = NULL;
+ bool child_keep_old = keep_old_opts;
/* reopen can only change the options of block devices that were
* implicitly created and inherited options. For other (referenced)
@@ -3118,13 +3130,32 @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue,
continue;
}
- child_key_dot = g_strdup_printf("%s.", child->name);
- qdict_extract_subqdict(explicit_options, NULL, child_key_dot);
- qdict_extract_subqdict(options, &new_child_options, child_key_dot);
- g_free(child_key_dot);
+ /* Check if the options contain a child reference */
+ if (qdict_haskey(options, child->name)) {
+ const char *childref = qdict_get_try_str(options, child->name);
+ /*
+ * The current child must not be reopened if the child
+ * reference is null or points to a different node.
+ */
+ if (g_strcmp0(childref, child->bs->node_name)) {
+ continue;
+ }
+ /*
+ * If the child reference points to the current child then
+ * reopen it with its existing set of options (note that
+ * it can still inherit new options from the parent).
+ */
+ child_keep_old = true;
+ } else {
+ /* Extract child options ("child-name.*") */
+ char *child_key_dot = g_strdup_printf("%s.", child->name);
+ qdict_extract_subqdict(explicit_options, NULL, child_key_dot);
+ qdict_extract_subqdict(options, &new_child_options, child_key_dot);
+ g_free(child_key_dot);
+ }
bdrv_reopen_queue_child(bs_queue, child->bs, new_child_options,
- child->role, options, flags, keep_old_opts);
+ child->role, options, flags, child_keep_old);
}
return bs_queue;
@@ -3403,6 +3434,13 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
drv_prepared = true;
+ if (drv->supports_backing && reopen_state->backing_missing) {
+ error_setg(errp, "backing is missing for '%s'",
+ reopen_state->bs->node_name);
+ ret = -EINVAL;
+ goto error;
+ }
+
/* Options that are not handled are only okay if they are unchanged
* compared to the old state. It is expected that some options are only
* used for the initial open, but not reopen (e.g. filename) */