[PATCH 6/8] Bluetooth: Move stream-oriented recvmsg code so it can be used by L2CAP.

[Mat Martineau <mathewm@codeaurora.org>]

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
---
 include/net/bluetooth/bluetooth.h |    2 +
 net/bluetooth/af_bluetooth.c      |  107 +++++++++++++++++++++++++++++++++++++
 net/bluetooth/rfcomm/sock.c       |  104 ++---------------------------------
 3 files changed, 115 insertions(+), 98 deletions(-)

diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index 27a902d..08b6c2a 100644
--- a/include/net/bluetooth/bluetooth.h
+++ b/include/net/bluetooth/bluetooth.h
@@ -126,6 +126,8 @@ int  bt_sock_unregister(int proto);
 void bt_sock_link(struct bt_sock_list *l, struct sock *s);
 void bt_sock_unlink(struct bt_sock_list *l, struct sock *s);
 int  bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len, int flags);
+int  bt_sock_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
+			struct msghdr *msg, size_t len, int flags);
 uint bt_sock_poll(struct file * file, struct socket *sock, poll_table *wait);
 int  bt_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
 int  bt_sock_wait_state(struct sock *sk, int state, unsigned long timeo);
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index 421c45b..73047f5 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -265,6 +265,113 @@ int bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 }
 EXPORT_SYMBOL(bt_sock_recvmsg);
 
+static long bt_sock_data_wait(struct sock *sk, long timeo)
+{
+	DECLARE_WAITQUEUE(wait, current);
+
+	add_wait_queue(sk_sleep(sk), &wait);
+	for (;;) {
+		set_current_state(TASK_INTERRUPTIBLE);
+
+		if (!skb_queue_empty(&sk->sk_receive_queue) ||
+		    sk->sk_err ||
+		    (sk->sk_shutdown & RCV_SHUTDOWN) ||
+		    signal_pending(current) ||
+		    !timeo)
+			break;
+
+		set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+		release_sock(sk);
+		timeo = schedule_timeout(timeo);
+		lock_sock(sk);
+		clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+	}
+
+	__set_current_state(TASK_RUNNING);
+	remove_wait_queue(sk_sleep(sk), &wait);
+	return timeo;
+}
+
+int bt_sock_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
+			       struct msghdr *msg, size_t size, int flags)
+{
+	struct sock *sk = sock->sk;
+	int err = 0;
+	size_t target, copied = 0;
+	long timeo;
+
+	if (flags & MSG_OOB)
+		return -EOPNOTSUPP;
+
+	msg->msg_namelen = 0;
+
+	BT_DBG("sk %p size %zu", sk, size);
+
+	lock_sock(sk);
+
+	target = sock_rcvlowat(sk, flags & MSG_WAITALL, size);
+	timeo  = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
+
+	do {
+		struct sk_buff *skb;
+		int chunk;
+
+		skb = skb_dequeue(&sk->sk_receive_queue);
+		if (!skb) {
+			if (copied >= target)
+				break;
+
+			if ((err = sock_error(sk)) != 0)
+				break;
+			if (sk->sk_shutdown & RCV_SHUTDOWN)
+				break;
+
+			err = -EAGAIN;
+			if (!timeo)
+				break;
+
+			timeo = bt_sock_data_wait(sk, timeo);
+
+			if (signal_pending(current)) {
+				err = sock_intr_errno(timeo);
+				goto out;
+			}
+			continue;
+		}
+
+		chunk = min_t(unsigned int, skb->len, size);
+		if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
+			skb_queue_head(&sk->sk_receive_queue, skb);
+			if (!copied)
+				copied = -EFAULT;
+			break;
+		}
+		copied += chunk;
+		size   -= chunk;
+
+		sock_recv_ts_and_drops(msg, sk, skb);
+
+		if (!(flags & MSG_PEEK)) {
+			skb_pull(skb, chunk);
+			if (skb->len) {
+				skb_queue_head(&sk->sk_receive_queue, skb);
+				break;
+			}
+			kfree_skb(skb);
+
+		} else {
+			/* put message back and return */
+			skb_queue_head(&sk->sk_receive_queue, skb);
+			break;
+		}
+	} while (size);
+
+out:
+	release_sock(sk);
+	return copied ? : err;
+}
+EXPORT_SYMBOL(bt_sock_stream_recvmsg);
+
 static inline unsigned int bt_accept_poll(struct sock *parent)
 {
 	struct list_head *p, *n;
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index 44a6232..5c92929 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -617,121 +617,29 @@ static int rfcomm_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 	return sent;
 }
 
-static long rfcomm_sock_data_wait(struct sock *sk, long timeo)
-{
-	DECLARE_WAITQUEUE(wait, current);
-
-	add_wait_queue(sk_sleep(sk), &wait);
-	for (;;) {
-		set_current_state(TASK_INTERRUPTIBLE);
-
-		if (!skb_queue_empty(&sk->sk_receive_queue) ||
-		    sk->sk_err ||
-		    (sk->sk_shutdown & RCV_SHUTDOWN) ||
-		    signal_pending(current) ||
-		    !timeo)
-			break;
-
-		set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
-		release_sock(sk);
-		timeo = schedule_timeout(timeo);
-		lock_sock(sk);
-		clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
-	}
-
-	__set_current_state(TASK_RUNNING);
-	remove_wait_queue(sk_sleep(sk), &wait);
-	return timeo;
-}
-
 static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 			       struct msghdr *msg, size_t size, int flags)
 {
 	struct sock *sk = sock->sk;
 	struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
-	int err = 0;
-	size_t target, copied = 0;
-	long timeo;
+	int len_or_err;
 
 	if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
 		rfcomm_dlc_accept(d);
 		return 0;
 	}
 
-	if (flags & MSG_OOB)
-		return -EOPNOTSUPP;
-
-	msg->msg_namelen = 0;
-
-	BT_DBG("sk %p size %zu", sk, size);
+	len_or_err = bt_sock_stream_recvmsg(iocb, sock, msg, size, flags);
 
 	lock_sock(sk);
+	if (!(flags & MSG_PEEK) && len_or_err > 0)
+		atomic_sub(len_or_err, &sk->sk_rmem_alloc);
 
-	target = sock_rcvlowat(sk, flags & MSG_WAITALL, size);
-	timeo  = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
-
-	do {
-		struct sk_buff *skb;
-		int chunk;
-
-		skb = skb_dequeue(&sk->sk_receive_queue);
-		if (!skb) {
-			if (copied >= target)
-				break;
-
-			if ((err = sock_error(sk)) != 0)
-				break;
-			if (sk->sk_shutdown & RCV_SHUTDOWN)
-				break;
-
-			err = -EAGAIN;
-			if (!timeo)
-				break;
-
-			timeo = rfcomm_sock_data_wait(sk, timeo);
-
-			if (signal_pending(current)) {
-				err = sock_intr_errno(timeo);
-				goto out;
-			}
-			continue;
-		}
-
-		chunk = min_t(unsigned int, skb->len, size);
-		if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
-			skb_queue_head(&sk->sk_receive_queue, skb);
-			if (!copied)
-				copied = -EFAULT;
-			break;
-		}
-		copied += chunk;
-		size   -= chunk;
-
-		sock_recv_ts_and_drops(msg, sk, skb);
-
-		if (!(flags & MSG_PEEK)) {
-			atomic_sub(chunk, &sk->sk_rmem_alloc);
-
-			skb_pull(skb, chunk);
-			if (skb->len) {
-				skb_queue_head(&sk->sk_receive_queue, skb);
-				break;
-			}
-			kfree_skb(skb);
-
-		} else {
-			/* put message back and return */
-			skb_queue_head(&sk->sk_receive_queue, skb);
-			break;
-		}
-	} while (size);
-
-out:
 	if (atomic_read(&sk->sk_rmem_alloc) <= (sk->sk_rcvbuf >> 2))
 		rfcomm_dlc_unthrottle(rfcomm_pi(sk)->dlc);
-
 	release_sock(sk);
-	return copied ? : err;
+
+	return len_or_err;
 }
 
 static int rfcomm_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
-- 
1.7.1

--
Mat Martineau
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum