Bluetooth: L2CAP: Add get_peer_pid callback

This adds a callback to read the socket pid.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

include/net/bluetooth/l2cap.h

@@ -660,6 +660,7 @@ struct l2cap_ops {
 	void			(*suspend) (struct l2cap_chan *chan);
 	void			(*set_shutdown) (struct l2cap_chan *chan);
 	long			(*get_sndtimeo) (struct l2cap_chan *chan);
+	struct pid		*(*get_peer_pid) (struct l2cap_chan *chan);
 	struct sk_buff		*(*alloc_skb) (struct l2cap_chan *chan,
 					       unsigned long hdr_len,
 					       unsigned long len, int nb);

net/bluetooth/l2cap_sock.c

@@ -1504,6 +1504,13 @@ static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan)
 	return sk->sk_sndtimeo;
 }
 
+static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan)
+{
+	struct sock *sk = chan->data;
+
+	return sk->sk_peer_pid;
+}
+
 static void l2cap_sock_suspend_cb(struct l2cap_chan *chan)
 {
 	struct sock *sk = chan->data;
@@ -1525,6 +1532,7 @@ static const struct l2cap_ops l2cap_chan_ops = {
 	.suspend		= l2cap_sock_suspend_cb,
 	.set_shutdown		= l2cap_sock_set_shutdown_cb,
 	.get_sndtimeo		= l2cap_sock_get_sndtimeo_cb,
+	.get_peer_pid		= l2cap_sock_get_peer_pid_cb,
 	.alloc_skb		= l2cap_sock_alloc_skb_cb,
 };