Bluetooth: ISO: Notify user space about failed bis connections

Some use cases require the user to be informed if BIG synchronization
fails. This commit makes it so that even if the BIG sync established
event arrives with error status, a new hconn is added for each BIS,
and the iso layer is notified about the failed connections.

Unsuccesful bis connections will be marked using the
HCI_CONN_BIG_SYNC_FAILED flag. From the iso layer, the POLLERR event
is triggered on the newly allocated bis sockets, before adding them
to the accept list of the parent socket.

From user space, a new fd for each failed bis connection will be
obtained by calling accept. The user should check for the POLLERR
event on the new socket, to determine if the connection was successful
or not.

The HCI_CONN_BIG_SYNC flag has been added to mark whether the BIG sync
has been successfully established. This flag is checked at bis cleanup,
so the HCI LE BIG Terminate Sync command is only issued if needed.

The BT_SK_BIG_SYNC flag indicates if BIG create sync has been called
for a listening socket, to avoid issuing the command everytime a BIGInfo
advertising report is received.

Signed-off-by: Iulia Tanasescu <iulia.tanasescu@nxp.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

1 files changed, 14 insertions, 23 deletions

diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index af7dc8131a8c..cccc2b8b60a8 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -735,6 +735,7 @@ struct iso_list_data {
 	int count;
 	struct iso_cig_params pdu;
 	bool big_term;
+	bool big_sync_term;
 };
 
 static void bis_list(struct hci_conn *conn, void *data)
@@ -752,17 +753,6 @@ static void bis_list(struct hci_conn *conn, void *data)
 	d->count++;
 }
 
-static void find_bis(struct hci_conn *conn, void *data)
-{
-	struct iso_list_data *d = data;
-
-	/* Ignore unicast */
-	if (bacmp(&conn->dst, BDADDR_ANY))
-		return;
-
-	d->count++;
-}
-
 static int terminate_big_sync(struct hci_dev *hdev, void *data)
 {
 	struct iso_list_data *d = data;
@@ -815,31 +805,26 @@ static int big_terminate_sync(struct hci_dev *hdev, void *data)
 	bt_dev_dbg(hdev, "big 0x%2.2x sync_handle 0x%4.4x", d->big,
 		   d->sync_handle);
 
-	/* Check if ISO connection is a BIS and terminate BIG if there are
-	 * no other connections using it.
-	 */
-	hci_conn_hash_list_state(hdev, find_bis, ISO_LINK, BT_CONNECTED, d);
-	if (d->count)
-		return 0;
-
-	hci_le_big_terminate_sync(hdev, d->big);
+	if (d->big_sync_term)
+		hci_le_big_terminate_sync(hdev, d->big);
 
 	return hci_le_pa_terminate_sync(hdev, d->sync_handle);
 }
 
-static int hci_le_big_terminate(struct hci_dev *hdev, u8 big, u16 sync_handle)
+static int hci_le_big_terminate(struct hci_dev *hdev, u8 big, struct hci_conn *conn)
 {
 	struct iso_list_data *d;
 	int ret;
 
-	bt_dev_dbg(hdev, "big 0x%2.2x sync_handle 0x%4.4x", big, sync_handle);
+	bt_dev_dbg(hdev, "big 0x%2.2x sync_handle 0x%4.4x", big, conn->sync_handle);
 
 	d = kzalloc(sizeof(*d), GFP_KERNEL);
 	if (!d)
 		return -ENOMEM;
 
 	d->big = big;
-	d->sync_handle = sync_handle;
+	d->sync_handle = conn->sync_handle;
+	d->big_sync_term = test_and_clear_bit(HCI_CONN_BIG_SYNC, &conn->flags);
 
 	ret = hci_cmd_sync_queue(hdev, big_terminate_sync, d,
 				 terminate_big_destroy);
@@ -875,8 +860,14 @@ static void bis_cleanup(struct hci_conn *conn)
 
 		hci_le_terminate_big(hdev, conn);
 	} else {
+		bis = hci_conn_hash_lookup_big_any_dst(hdev,
+						       conn->iso_qos.bcast.big);
+
+		if (bis)
+			return;
+
 		hci_le_big_terminate(hdev, conn->iso_qos.bcast.big,
-				     conn->sync_handle);
+				     conn);
 	}
 }