[PATCH v5 4/6] Bluetooth: hci_conn: Make unacked packet handling more robust

[Luiz Augusto von Dentz <luiz.dentz@xxxxxxxxx>]

From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>

This attempts to make unacked packet handling more robust by detecting
if there are no connections left then restore all buffers of the
respective pool.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
---
 net/bluetooth/hci_conn.c | 40 +++++++++++++++++++++++++++++++---------
 1 file changed, 31 insertions(+), 9 deletions(-)

diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 9d2324eb1211..3ba0d0bee48e 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -149,8 +149,6 @@ static void hci_conn_cleanup(struct hci_conn *conn)
 
 	hci_chan_list_flush(conn);
 
-	hci_conn_hash_del(hdev, conn);
-
 	if (HCI_CONN_HANDLE_UNSET(conn->handle))
 		ida_free(&hdev->unset_handle_ida, conn->handle);
 
@@ -1151,23 +1149,47 @@ void hci_conn_del(struct hci_conn *conn)
 	disable_delayed_work_sync(&conn->auto_accept_work);
 	disable_delayed_work_sync(&conn->idle_work);
 
-	/* Handle unnacked frames */
+	/* Remove the connection from the list so unacked logic can detect when
+	 * a certain pool is not being utilized.
+	 */
+	hci_conn_hash_del(hdev, conn);
+
+	/* Handle unacked frames:
+	 *
+	 * - In case there are no connection restore all buffers to the pool
+	 * - Otherwise restore just the buffers considered in transit for the
+	 *   hci_conn
+	 */
 	switch (conn->type) {
 	case ACL_LINK:
-		hdev->acl_cnt += conn->sent;
+		if (!hci_conn_num(hdev, ACL_LINK))
+			hdev->acl_cnt = hdev->acl_pkts;
+		else
+			hdev->acl_cnt += conn->sent;
 		break;
 	case LE_LINK:
 		cancel_delayed_work(&conn->le_conn_timeout);
 
-		if (hdev->le_pkts)
-			hdev->le_cnt += conn->sent;
-		else
-			hdev->acl_cnt += conn->sent;
+		if (hdev->le_pkts) {
+			if (!hci_conn_num(hdev, LE_LINK))
+				hdev->le_cnt = hdev->le_pkts;
+			else
+				hdev->le_cnt += conn->sent;
+		} else {
+			if (!hci_conn_num(hdev, LE_LINK) &&
+			    !hci_conn_num(hdev, ACL_LINK))
+				hdev->acl_cnt = hdev->acl_pkts;
+			else
+				hdev->acl_cnt += conn->sent;
+		}
 		break;
 	case CIS_LINK:
 	case BIS_LINK:
 	case PA_LINK:
-		hdev->iso_cnt += conn->sent;
+		if (!hci_iso_count(hdev))
+			hdev->iso_cnt = hdev->iso_pkts;
+		else
+			hdev->iso_cnt += conn->sent;
 		break;
 	}
 
-- 
2.50.1