mptcp: remove mptcp_read_actor

Only used to discard stale data from the subflow, so move
it where needed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mptcp/protocol.c

@@ -430,33 +430,6 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	return ret;
 }
 
-int mptcp_read_actor(read_descriptor_t *desc, struct sk_buff *skb,
-		     unsigned int offset, size_t len)
-{
-	struct mptcp_read_arg *arg = desc->arg.data;
-	size_t copy_len;
-
-	copy_len = min(desc->count, len);
-
-	if (likely(arg->msg)) {
-		int err;
-
-		err = skb_copy_datagram_msg(skb, offset, arg->msg, copy_len);
-		if (err) {
-			pr_debug("error path");
-			desc->error = err;
-			return err;
-		}
-	} else {
-		pr_debug("Flushing skb payload");
-	}
-
-	desc->count -= copy_len;
-
-	pr_debug("consumed %zu bytes, %zu left", copy_len, desc->count);
-	return copy_len;
-}
-
 static void mptcp_wait_data(struct sock *sk, long *timeo)
 {
 	DEFINE_WAIT_FUNC(wait, woken_wake_function);

net/mptcp/protocol.h

@@ -191,13 +191,6 @@ void mptcp_proto_init(void);
 int mptcp_proto_v6_init(void);
 #endif
 
-struct mptcp_read_arg {
-	struct msghdr *msg;
-};
-
-int mptcp_read_actor(read_descriptor_t *desc, struct sk_buff *skb,
-		     unsigned int offset, size_t len);
-
 void mptcp_get_options(const struct sk_buff *skb,
 		       struct tcp_options_received *opt_rx);
 

net/mptcp/subflow.c

@@ -408,6 +408,18 @@ static enum mapping_status get_mapping_status(struct sock *ssk)
 	return MAPPING_OK;
 }
 
+static int subflow_read_actor(read_descriptor_t *desc,
+			      struct sk_buff *skb,
+			      unsigned int offset, size_t len)
+{
+	size_t copy_len = min(desc->count, len);
+
+	desc->count -= copy_len;
+
+	pr_debug("flushed %zu bytes, %zu left", copy_len, desc->count);
+	return copy_len;
+}
+
 static bool subflow_check_data_avail(struct sock *ssk)
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
@@ -482,16 +494,12 @@ static bool subflow_check_data_avail(struct sock *ssk)
 		pr_debug("discarding %zu bytes, current map len=%d", delta,
 			 map_remaining);
 		if (delta) {
-			struct mptcp_read_arg arg = {
-				.msg = NULL,
-			};
 			read_descriptor_t desc = {
 				.count = delta,
-				.arg.data = &arg,
 			};
 			int ret;
 
-			ret = tcp_read_sock(ssk, &desc, mptcp_read_actor);
+			ret = tcp_read_sock(ssk, &desc, subflow_read_actor);
 			if (ret < 0) {
 				ssk->sk_err = -ret;
 				goto fatal;