rxrpc: Fix warning by splitting rxrpc_send_call_packet()

Split rxrpc_send_data_packet() to separate ACK generation (which is more
complicated) from ABORT generation.  This simplifies the code a bit and
fixes the following warning:

In file included from ../net/rxrpc/output.c:20:0:
net/rxrpc/output.c: In function 'rxrpc_send_call_packet':
net/rxrpc/ar-internal.h:1187:27: error: 'top' may be used uninitialized in this function [-Werror=maybe-uninitialized]
net/rxrpc/output.c:103:24: note: 'top' was declared here
net/rxrpc/output.c:225:25: error: 'hard_ack' may be used uninitialized in this function [-Werror=maybe-uninitialized]

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 87 insertions, 69 deletions

diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 0d47db886f6e..2dae877c0876 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -19,24 +19,24 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
-struct rxrpc_pkt_buffer {
+struct rxrpc_ack_buffer {
 	struct rxrpc_wire_header whdr;
-	union {
-		struct {
-			struct rxrpc_ackpacket ack;
-			u8 acks[255];
-			u8 pad[3];
-		};
-		__be32 abort_code;
-	};
+	struct rxrpc_ackpacket ack;
+	u8 acks[255];
+	u8 pad[3];
 	struct rxrpc_ackinfo ackinfo;
 };
 
+struct rxrpc_abort_buffer {
+	struct rxrpc_wire_header whdr;
+	__be32 abort_code;
+};
+
 /*
  * Fill out an ACK packet.
  */
 static size_t rxrpc_fill_out_ack(struct rxrpc_call *call,
-				 struct rxrpc_pkt_buffer *pkt,
+				 struct rxrpc_ack_buffer *pkt,
 				 rxrpc_seq_t *_hard_ack,
 				 rxrpc_seq_t *_top)
 {
@@ -91,22 +91,19 @@ static size_t rxrpc_fill_out_ack(struct rxrpc_call *call,
 }
 
 /*
- * Send an ACK or ABORT call packet.
+ * Send an ACK call packet.
  */
-int rxrpc_send_call_packet(struct rxrpc_call *call, u8 type)
+int rxrpc_send_ack_packet(struct rxrpc_call *call)
 {
 	struct rxrpc_connection *conn = NULL;
-	struct rxrpc_pkt_buffer *pkt;
+	struct rxrpc_ack_buffer *pkt;
 	struct msghdr msg;
 	struct kvec iov[2];
 	rxrpc_serial_t serial;
 	rxrpc_seq_t hard_ack, top;
 	size_t len, n;
 	bool ping = false;
-	int ioc, ret;
-	u32 abort_code;
-
-	_enter("%u,%s", call->debug_id, rxrpc_pkts[type]);
+	int ret;
 
 	spin_lock_bh(&call->lock);
 	if (call->conn)
@@ -131,65 +128,37 @@ int rxrpc_send_call_packet(struct rxrpc_call *call, u8 type)
 	pkt->whdr.cid		= htonl(call->cid);
 	pkt->whdr.callNumber	= htonl(call->call_id);
 	pkt->whdr.seq		= 0;
-	pkt->whdr.type		= type;
-	pkt->whdr.flags		= conn->out_clientflag;
+	pkt->whdr.type		= RXRPC_PACKET_TYPE_ACK;
+	pkt->whdr.flags		= RXRPC_SLOW_START_OK | conn->out_clientflag;
 	pkt->whdr.userStatus	= 0;
 	pkt->whdr.securityIndex	= call->security_ix;
 	pkt->whdr._rsvd		= 0;
 	pkt->whdr.serviceId	= htons(call->service_id);
 
-	iov[0].iov_base	= pkt;
-	iov[0].iov_len	= sizeof(pkt->whdr);
-	len = sizeof(pkt->whdr);
-
-	switch (type) {
-	case RXRPC_PACKET_TYPE_ACK:
-		spin_lock_bh(&call->lock);
-		if (!call->ackr_reason) {
-			spin_unlock_bh(&call->lock);
-			ret = 0;
-			goto out;
-		}
-		ping = (call->ackr_reason == RXRPC_ACK_PING);
-		n = rxrpc_fill_out_ack(call, pkt, &hard_ack, &top);
-		call->ackr_reason = 0;
-
+	spin_lock_bh(&call->lock);
+	if (!call->ackr_reason) {
 		spin_unlock_bh(&call->lock);
-
-
-		pkt->whdr.flags |= RXRPC_SLOW_START_OK;
-
-		iov[0].iov_len += sizeof(pkt->ack) + n;
-		iov[1].iov_base = &pkt->ackinfo;
-		iov[1].iov_len	= sizeof(pkt->ackinfo);
-		len += sizeof(pkt->ack) + n + sizeof(pkt->ackinfo);
-		ioc = 2;
-		break;
-
-	case RXRPC_PACKET_TYPE_ABORT:
-		abort_code = call->abort_code;
-		pkt->abort_code = htonl(abort_code);
-		iov[0].iov_len += sizeof(pkt->abort_code);
-		len += sizeof(pkt->abort_code);
-		ioc = 1;
-		break;
-
-	default:
-		BUG();
-		ret = -ENOANO;
+		ret = 0;
 		goto out;
 	}
+	ping = (call->ackr_reason == RXRPC_ACK_PING);
+	n = rxrpc_fill_out_ack(call, pkt, &hard_ack, &top);
+	call->ackr_reason = 0;
+
+	spin_unlock_bh(&call->lock);
+
+	iov[0].iov_base	= pkt;
+	iov[0].iov_len	= sizeof(pkt->whdr) + sizeof(pkt->ack) + n;
+	iov[1].iov_base = &pkt->ackinfo;
+	iov[1].iov_len	= sizeof(pkt->ackinfo);
+	len = iov[0].iov_len + iov[1].iov_len;
 
 	serial = atomic_inc_return(&conn->serial);
 	pkt->whdr.serial = htonl(serial);
-	switch (type) {
-	case RXRPC_PACKET_TYPE_ACK:
-		trace_rxrpc_tx_ack(call, serial,
-				   ntohl(pkt->ack.firstPacket),
-				   ntohl(pkt->ack.serial),
-				   pkt->ack.reason, pkt->ack.nAcks);
-		break;
-	}
+	trace_rxrpc_tx_ack(call, serial,
+			   ntohl(pkt->ack.firstPacket),
+			   ntohl(pkt->ack.serial),
+			   pkt->ack.reason, pkt->ack.nAcks);
 
 	if (ping) {
 		call->ackr_ping = serial;
@@ -205,13 +174,12 @@ int rxrpc_send_call_packet(struct rxrpc_call *call, u8 type)
 		set_bit(RXRPC_CALL_PINGING, &call->flags);
 		trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_ping, serial);
 	}
-	ret = kernel_sendmsg(conn->params.local->socket,
-			     &msg, iov, ioc, len);
+
+	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
 	if (ping)
 		call->ackr_ping_time = ktime_get_real();
 
-	if (type == RXRPC_PACKET_TYPE_ACK &&
-	    call->state < RXRPC_CALL_COMPLETE) {
+	if (call->state < RXRPC_CALL_COMPLETE) {
 		if (ret < 0) {
 			clear_bit(RXRPC_CALL_PINGING, &call->flags);
 			rxrpc_propose_ACK(call, pkt->ack.reason,
@@ -236,6 +204,56 @@ out:
 }
 
 /*
+ * Send an ABORT call packet.
+ */
+int rxrpc_send_abort_packet(struct rxrpc_call *call)
+{
+	struct rxrpc_connection *conn = NULL;
+	struct rxrpc_abort_buffer pkt;
+	struct msghdr msg;
+	struct kvec iov[1];
+	rxrpc_serial_t serial;
+	int ret;
+
+	spin_lock_bh(&call->lock);
+	if (call->conn)
+		conn = rxrpc_get_connection_maybe(call->conn);
+	spin_unlock_bh(&call->lock);
+	if (!conn)
+		return -ECONNRESET;
+
+	msg.msg_name	= &call->peer->srx.transport;
+	msg.msg_namelen	= call->peer->srx.transport_len;
+	msg.msg_control	= NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags	= 0;
+
+	pkt.whdr.epoch		= htonl(conn->proto.epoch);
+	pkt.whdr.cid		= htonl(call->cid);
+	pkt.whdr.callNumber	= htonl(call->call_id);
+	pkt.whdr.seq		= 0;
+	pkt.whdr.type		= RXRPC_PACKET_TYPE_ABORT;
+	pkt.whdr.flags		= conn->out_clientflag;
+	pkt.whdr.userStatus	= 0;
+	pkt.whdr.securityIndex	= call->security_ix;
+	pkt.whdr._rsvd		= 0;
+	pkt.whdr.serviceId	= htons(call->service_id);
+	pkt.abort_code		= htonl(call->abort_code);
+
+	iov[0].iov_base	= &pkt;
+	iov[0].iov_len	= sizeof(pkt);
+
+	serial = atomic_inc_return(&conn->serial);
+	pkt.whdr.serial = htonl(serial);
+
+	ret = kernel_sendmsg(conn->params.local->socket,
+			     &msg, iov, 1, sizeof(pkt));
+
+	rxrpc_put_connection(conn);
+	return ret;
+}
+
+/*
  * send a packet through the transport endpoint
  */
 int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,