async: Register/unregister aiocontext in graph lock list

Add/remove the AioContext in aio_context_list in graph-lock.c when it is
created/destroyed. This allows using the graph locking operations from
this AioContext.

In order to allow linking util/async.c with binaries that don't include
the block layer, introduce stubs for (un)register_aiocontext().

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-5-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/stubs/graph-lock.c b/stubs/graph-lock.c
new file mode 100644
index 0000000000..177aa0a8ba
--- /dev/null
+++ b/stubs/graph-lock.c
@@ -0,0 +1,10 @@
+#include "qemu/osdep.h"
+#include "block/graph-lock.h"
+
+void register_aiocontext(AioContext *ctx)
+{
+}
+
+void unregister_aiocontext(AioContext *ctx)
+{
+}