If the child was defined in the same context (-drive argument or blockdev-add QMP command) as its parent, a reopen of the parent should work the same and allow changing options of the child.
Signed-off-by: Kevin Wolf <kw...@redhat.com> Reviewed-by: Max Reitz <mre...@redhat.com> Reviewed-by: Alberto Garcia <be...@igalia.com> --- block.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index 2728bc5..a800d9e 100644 --- a/block.c +++ b/block.c @@ -1720,15 +1720,23 @@ BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, flags &= ~BDRV_O_PROTOCOL; QLIST_FOREACH(child, &bs->children, next) { + QDict *new_child_options; + char *child_key_dot; int child_flags; + /* reopen can only change the options of block devices that were + * implicitly created and inherited options. For other (referenced) + * block devices, a syntax like "backing.foo" results in an error. */ if (child->bs->inherits_from != bs) { continue; } + child_key_dot = g_strdup_printf("%s.", child->name); + qdict_extract_subqdict(options, &new_child_options, child_key_dot); + g_free(child_key_dot); + child_flags = child->role->inherit_flags(flags); - /* TODO Pass down child flags (backing.*, extents.*, ...) */ - bdrv_reopen_queue(bs_queue, child->bs, NULL, child_flags); + bdrv_reopen_queue(bs_queue, child->bs, new_child_options, child_flags); } bs_entry = g_new0(BlockReopenQueueEntry, 1); -- 1.8.3.1