Bluetooth: Fix bt_buff lifecycle

Signed-off-by: Brennan Ashton <bashton@brennanashton.com>

arch/sim/src/sim/up_hcisocket.c

@@ -120,8 +120,6 @@ static int bthcisock_send(FAR const struct bt_driver_s *dev,
       return -1;
     }
 
-  bt_buf_release(buf);
-
   return buf->len;
 }
 

wireless/bluetooth/bt_conn.c

@@ -178,7 +178,7 @@ static int conn_tx_kthread(int argc, FAR char *argv[])
         }
 
       wlinfo("passing buf %p len %u to driver\n", buf, buf->len);
-      g_btdev.btdev->send(g_btdev.btdev, buf);
+      bt_send(g_btdev.btdev, buf);
       bt_buf_release(buf);
     }
 

wireless/bluetooth/bt_hcicore.c

@@ -124,30 +124,6 @@ static struct work_s g_hp_work;
  * Private Functions
  ****************************************************************************/
 
-/****************************************************************************
- * Name: bt_send
- *
- * Description:
- *   Add the provided buffer 'buf' to the head selected buffer list 'list'
- *
- * Input Parameters:
- *   btdev - An instance of the low-level drivers interface structure.
- *   buf   - The buffer to be sent by the driver
- *
- * Returned Value:
- *   Zero is returned on success; a negated errno value is returned on any
- *   failure.
- *
- ****************************************************************************/
-
-static int bt_send(FAR const struct bt_driver_s *btdev,
-                   FAR struct bt_buf_s *buf)
-{
-  /* TODDO: Hook here to notify hci monitor */
-
-  return btdev->send(btdev, buf);
-}
-
 /****************************************************************************
  * Name: bt_enqueue_bufwork
  *
@@ -354,9 +330,17 @@ static void hci_cmd_done(uint16_t opcode, uint8_t status,
       return;
     }
 
+  if (g_btdev.sent_cmd == NULL)
+    {
+      wlerr("ERROR: Request cmd missing!\n");
+      return;
+    }
+
   if (g_btdev.sent_cmd->u.hci.opcode != opcode)
     {
-      wlerr("ERROR:  Unexpected completion of opcode 0x%04x\n", opcode);
+      wlerr("ERROR:  Unexpected completion of opcode 0x%04x " \
+            "expected 0x%04x\n",
+            opcode, g_btdev.sent_cmd->u.hci.opcode);
       return;
     }
 
@@ -380,10 +364,8 @@ static void hci_cmd_done(uint16_t opcode, uint8_t status,
 
       nxsem_post(sem);
     }
-  else
-    {
-      bt_buf_release(sent);
-    }
+
+  bt_buf_release(sent);
 }
 
 static void hci_cmd_complete(FAR struct bt_buf_s *buf)
@@ -1045,12 +1027,13 @@ static int hci_tx_kthread(int argc, FAR char *argv[])
           g_btdev.sent_cmd = NULL;
         }
 
-      g_btdev.sent_cmd = buf;
+      g_btdev.sent_cmd = bt_buf_addref(buf);
 
       wlinfo("Sending command %04x buf %p to driver\n",
              buf->u.hci.opcode, buf);
 
-      btdev->send(btdev, buf);
+      bt_send(btdev, buf);
+      bt_buf_release(buf);
     }
 
   return EXIT_SUCCESS;  /* Can't get here */
@@ -1104,6 +1087,7 @@ static void hci_rx_work(FAR void *arg)
 #else
       g_hci_cb->received(buf, g_hci_cb->context);
 #endif
+      bt_buf_release(buf);
     }
 }
 
@@ -1171,6 +1155,7 @@ static void priority_rx_work(FAR void *arg)
 
       g_hci_cb->received(buf, g_hci_cb->context);
 #endif
+      bt_buf_release(buf);
     }
 }
 
@@ -1486,6 +1471,36 @@ static void cmd_queue_init(void)
  * Public Functions
  ****************************************************************************/
 
+/****************************************************************************
+ * Name: bt_send
+ *
+ * Description:
+ *   Send the provided buffer to the bluetooth driver
+ *
+ * Input Parameters:
+ *   btdev - An instance of the low-level drivers interface structure.
+ *   buf   - The buffer to be sent by the driver
+ *
+ * Returned Value:
+ *   Zero is returned on success; a negated errno value is returned on any
+ *   failure.
+ *
+ ****************************************************************************/
+
+int bt_send(FAR const struct bt_driver_s *btdev,
+            FAR struct bt_buf_s *buf)
+{
+  int ret;
+
+  /* Send to driver */
+
+  ret = btdev->send(btdev, buf);
+
+  /* TODO: Hook here to notify hci monitor */
+
+  return ret;
+}
+
 /****************************************************************************
  * Name: bt_initialize
  *
@@ -1731,6 +1746,15 @@ int bt_hci_cmd_send(uint16_t opcode, FAR struct bt_buf_s *buf)
           return -ENOBUFS;
         }
     }
+  else
+    {
+      /* We manage the refcount the same for supplied and created
+       * buffers so increment the supplied count so we can manage
+       * it as-if we crated it.
+       */
+
+      bt_buf_addref(buf);
+    }
 
   wlinfo("opcode %04x len %u\n", opcode, buf->len);
 
@@ -1774,6 +1798,10 @@ int bt_hci_cmd_send_sync(uint16_t opcode, FAR struct bt_buf_s *buf,
           return -ENOBUFS;
         }
     }
+  else
+    {
+      bt_buf_addref(buf);
+    }
 
   wlinfo("opcode %04x len %u\n", opcode, buf->len);
 
@@ -1850,12 +1878,21 @@ int bt_hci_cmd_send_sync(uint16_t opcode, FAR struct bt_buf_s *buf,
         }
     }
 
+  /* Note: if ret < 0 the packet might just be delayed and could still
+   * be sent.  We cannot decrease the ref count since it if it was sent
+   * it buf could be pointed a completely different request.
+   */
+
   if (rsp != NULL)
     {
+      /* If the response is expected provide the sync response */
+
       *rsp = buf->u.hci.sync;
     }
   else if (buf->u.hci.sync != NULL)
     {
+      /* If a sync response was given but not requested drop it */
+
       bt_buf_release(buf->u.hci.sync);
     }
 

wireless/bluetooth/bt_hcicore.h

@@ -302,6 +302,25 @@ int bt_driver_register(FAR const struct bt_driver_s *btdev);
 
 void bt_driver_unregister(FAR const struct bt_driver_s *btdev);
 
+/****************************************************************************
+ * Name: bt_send
+ *
+ * Description:
+ *   Add the provided buffer 'buf' to the head selected buffer list 'list'
+ *
+ * Input Parameters:
+ *   btdev - An instance of the low-level drivers interface structure.
+ *   buf   - The buffer to be sent by the driver
+ *
+ * Returned Value:
+ *   Zero is returned on success; a negated errno value is returned on any
+ *   failure.
+ *
+ ****************************************************************************/
+
+int bt_send(FAR const struct bt_driver_s *btdev,
+            FAR struct bt_buf_s *buf);
+
 #ifdef CONFIG_WIRELESS_BLUETOOTH_HOST
 /****************************************************************************
  * Name: bt_hci_cmd_create

wireless/bluetooth/bt_netdev.c

@@ -615,7 +615,6 @@ drop:
 
   /* Release our reference on the buffer */
 
-  bt_buf_release(buf);
   net_unlock();
 }
 
@@ -1222,7 +1221,8 @@ static int  btnet_req_hci_data(FAR struct btnet_driver_s *priv,
           return -ENOMEM;
         }
 
-      g_btdev.btdev->send(g_btdev.btdev, buf);
+      bt_send(g_btdev.btdev, buf);
+      bt_buf_release(buf);
 
       /* Transfer the frame to the Bluetooth stack. */