From dcec3f12b5b61d33fe333c4037cf0a34faa2b705 Mon Sep 17 00:00:00 2001
From: Wim Taymans <wtaymans@redhat.com>
Date: Tue, 4 Feb 2020 16:29:48 +0100
Subject: [PATCH] remote-node: safely activate and deactivate a link

Make sure we execute the admin of the target links in the data
thread.
---
 src/modules/module-client-node/remote-node.c | 42 +++++++++++++++-----
 1 file changed, 33 insertions(+), 9 deletions(-)

diff --git a/src/modules/module-client-node/remote-node.c b/src/modules/module-client-node/remote-node.c
index cb5ce75c5..0cf9cae6b 100644
--- a/src/modules/module-client-node/remote-node.c
+++ b/src/modules/module-client-node/remote-node.c
@@ -61,13 +61,6 @@ struct mix {
 	bool active;
 };
 
-struct link {
-	uint32_t node_id;
-	struct pw_memmap *map;
-	struct pw_node_target target;
-	int signalfd;
-};
-
 struct node_data {
 	struct pw_context *context;
 
@@ -98,6 +91,14 @@ struct node_data {
 	struct pw_array links;
 };
 
+struct link {
+	struct node_data *data;
+	struct pw_memmap *map;
+	struct pw_node_target target;
+	uint32_t node_id;
+	int signalfd;
+};
+
 /** \endcond */
 
 static struct link *find_activation(struct pw_array *links, uint32_t node_id)
@@ -111,13 +112,23 @@ static struct link *find_activation(struct pw_array *links, uint32_t node_id)
 	return NULL;
 }
 
+static int
+do_deactivate_link(struct spa_loop *loop,
+                bool async, uint32_t seq, const void *data, size_t size, void *user_data)
+{
+	struct link *link = user_data;
+	spa_list_remove(&link->target.link);
+        return 0;
+}
+
 static void clear_link(struct node_data *data, struct link *link)
 {
+	pw_loop_invoke(data->context->data_loop,
+		do_deactivate_link, SPA_ID_INVALID, NULL, 0, true, link);
 	link->node_id = SPA_ID_INVALID;
 	link->target.activation = NULL;
 	pw_memmap_free(link->map);
 	close(link->signalfd);
-	spa_list_remove(&link->target.link);
 }
 
 static void clean_transport(struct node_data *data)
@@ -798,6 +809,16 @@ static int link_signal_func(void *user_data)
 	return 0;
 }
 
+static int
+do_activate_link(struct spa_loop *loop,
+                bool async, uint32_t seq, const void *data, size_t size, void *user_data)
+{
+	struct link *link = user_data;
+	struct node_data *d = link->data;
+	spa_list_append(&d->node->rt.target_list, &link->target.link);
+        return 0;
+}
+
 static int
 client_node_set_activation(void *object,
                         uint32_t node_id,
@@ -843,6 +864,7 @@ client_node_set_activation(void *object,
 			res = -errno;
 			goto error_exit;
 		}
+		link->data = data;
 		link->node_id = node_id;
 		link->map = mm;
 		link->target.activation = ptr;
@@ -850,7 +872,9 @@ client_node_set_activation(void *object,
 		link->target.signal = link_signal_func;
 		link->target.data = link;
 		link->target.node = NULL;
-		spa_list_append(&node->rt.target_list, &link->target.link);
+
+		pw_loop_invoke(data->context->data_loop,
+                       do_activate_link, SPA_ID_INVALID, NULL, 0, false, link);
 
 		pw_log_debug("node %p: link %p: fd:%d id:%u state %p required %d, pending %d",
 				node, link, signalfd,