NFC: LLCP socket sendmsg implemetation

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/nfc/llcp/commands.c

@@ -397,3 +397,34 @@ int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
 
 	return 0;
 }
+
+int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
+				struct msghdr *msg, size_t len)
+{
+	struct sk_buff *pdu;
+	struct sock *sk;
+
+	pr_debug("Send I frame\n");
+
+	pdu = llcp_allocate_pdu(sock, LLCP_PDU_I, len + LLCP_SEQUENCE_SIZE);
+	if (pdu == NULL)
+		return -ENOMEM;
+
+	skb_put(pdu, LLCP_SEQUENCE_SIZE);
+
+	if (memcpy_fromiovec(skb_put(pdu, len), msg->msg_iov, len)) {
+		kfree_skb(pdu);
+		return -EFAULT;
+	}
+
+	skb_queue_head(&sock->tx_queue, pdu);
+
+	sk = &sock->sk;
+	lock_sock(sk);
+
+	nfc_llcp_queue_i_frames(sock);
+
+	release_sock(sk);
+
+	return 0;
+}

net/nfc/llcp/llcp.h

@@ -188,6 +188,8 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock);
 int nfc_llcp_send_cc(struct nfc_llcp_sock *sock);
 int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason);
 int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock);
+int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
+				struct msghdr *msg, size_t len);
 
 /* Socket API */
 int __init nfc_llcp_sock_init(void);

net/nfc/llcp/sock.c

@@ -482,6 +482,34 @@ static int llcp_sock_connect(struct socket *sock, struct sockaddr *_addr,
 	return ret;
 }
 
+static int llcp_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
+				struct msghdr *msg, size_t len)
+{
+	struct sock *sk = sock->sk;
+	struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
+	int ret;
+
+	pr_debug("sock %p sk %p", sock, sk);
+
+	ret = sock_error(sk);
+	if (ret)
+		return ret;
+
+	if (msg->msg_flags & MSG_OOB)
+		return -EOPNOTSUPP;
+
+	lock_sock(sk);
+
+	if (sk->sk_state != LLCP_CONNECTED) {
+		release_sock(sk);
+		return -ENOTCONN;
+	}
+
+	release_sock(sk);
+
+	return nfc_llcp_send_i_frame(llcp_sock, msg, len);
+}
+
 static int llcp_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 			     struct msghdr *msg, size_t len, int flags)
 {
@@ -567,7 +595,7 @@ static const struct proto_ops llcp_sock_ops = {
 	.shutdown       = sock_no_shutdown,
 	.setsockopt     = sock_no_setsockopt,
 	.getsockopt     = sock_no_getsockopt,
-	.sendmsg        = sock_no_sendmsg,
+	.sendmsg        = llcp_sock_sendmsg,
 	.recvmsg        = llcp_sock_recvmsg,
 	.mmap           = sock_no_mmap,
 };