[Bluetooth] Add timestamp support to L2CAP, RFCOMM and SCO

Enable the common timestamp functionality that the network subsystem
provides for L2CAP, RFCOMM and SCO sockets. It is possible to either
use SO_TIMESTAMP or the IOCTLs to retrieve the timestamp of the
current packet.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index d366423..88afe25 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -36,6 +36,7 @@
 #include <linux/init.h>
 #include <linux/poll.h>
 #include <net/sock.h>
+#include <asm/ioctls.h>
 
 #if defined(CONFIG_KMOD)
 #include <linux/kmod.h>
@@ -266,6 +267,8 @@
 
 	skb_reset_transport_header(skb);
 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
+	if (err == 0)
+		sock_recv_timestamp(msg, sk, skb);
 
 	skb_free_datagram(sk, skb);
 
@@ -329,6 +332,31 @@
 }
 EXPORT_SYMBOL(bt_sock_poll);
 
+int bt_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	struct sock *sk = sock->sk;
+	int err;
+
+	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
+
+	switch (cmd) {
+	case SIOCGSTAMP:
+		err = sock_get_timestamp(sk, (struct timeval __user *) arg);
+		break;
+
+	case SIOCGSTAMPNS:
+		err = sock_get_timestampns(sk, (struct timespec __user *) arg);
+		break;
+
+	default:
+		err = -ENOIOCTLCMD;
+		break;
+	}
+
+	return err;
+}
+EXPORT_SYMBOL(bt_sock_ioctl);
+
 int bt_sock_wait_state(struct sock *sk, int state, unsigned long timeo)
 {
 	DECLARE_WAITQUEUE(wait, current);