migration: Introduce migration_ioc_[un]register_yank()

There're plenty of places in migration/* that checks against either socket or
tls typed ioc for yank operations.  Provide two helpers to hide all these
information.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210722175841.938739-4-peterx@redhat.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/migration/yank_functions.c b/migration/yank_functions.c
index 96c90e17dc..23697173ae 100644
--- a/migration/yank_functions.c
+++ b/migration/yank_functions.c
@@ -11,6 +11,9 @@
 #include "qapi/error.h"
 #include "io/channel.h"
 #include "yank_functions.h"
+#include "qemu/yank.h"
+#include "io/channel-socket.h"
+#include "io/channel-tls.h"
 
 void migration_yank_iochannel(void *opaque)
 {
@@ -18,3 +21,28 @@ void migration_yank_iochannel(void *opaque)
 
     qio_channel_shutdown(ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
 }
+
+/* Return whether yank is supported on this ioc */
+static bool migration_ioc_yank_supported(QIOChannel *ioc)
+{
+    return object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_SOCKET) ||
+        object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_TLS);
+}
+
+void migration_ioc_register_yank(QIOChannel *ioc)
+{
+    if (migration_ioc_yank_supported(ioc)) {
+        yank_register_function(MIGRATION_YANK_INSTANCE,
+                               migration_yank_iochannel,
+                               QIO_CHANNEL(ioc));
+    }
+}
+
+void migration_ioc_unregister_yank(QIOChannel *ioc)
+{
+    if (migration_ioc_yank_supported(ioc)) {
+        yank_unregister_function(MIGRATION_YANK_INSTANCE,
+                                 migration_yank_iochannel,
+                                 QIO_CHANNEL(ioc));
+    }
+}