rxrpc: Clean up connection abort

Clean up connection abort, using the connection state_lock to gate access
to change that state, and use an rxrpc_call_completion value to indicate
the difference between local and remote aborts as these can be pasted
directly into the call state.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org

1 files changed, 81 insertions, 152 deletions

diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 7a980a32344f..753d91a9646f 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -17,6 +17,60 @@
 #include "ar-internal.h"
 
 /*
+ * Set the completion state on an aborted connection.
+ */
+static bool rxrpc_set_conn_aborted(struct rxrpc_connection *conn, struct sk_buff *skb,
+				   s32 abort_code, int err,
+				   enum rxrpc_call_completion compl)
+{
+	bool aborted = false;
+
+	if (conn->state != RXRPC_CONN_ABORTED) {
+		spin_lock(&conn->state_lock);
+		if (conn->state != RXRPC_CONN_ABORTED) {
+			conn->abort_code = abort_code;
+			conn->error	 = err;
+			conn->completion = compl;
+			/* Order the abort info before the state change. */
+			smp_store_release(&conn->state, RXRPC_CONN_ABORTED);
+			set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
+			set_bit(RXRPC_CONN_EV_ABORT_CALLS, &conn->events);
+			aborted = true;
+		}
+		spin_unlock(&conn->state_lock);
+	}
+
+	return aborted;
+}
+
+/*
+ * Mark a socket buffer to indicate that the connection it's on should be aborted.
+ */
+int rxrpc_abort_conn(struct rxrpc_connection *conn, struct sk_buff *skb,
+		     s32 abort_code, int err, const char *why)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+
+	if (rxrpc_set_conn_aborted(conn, skb, abort_code, err,
+				   RXRPC_CALL_LOCALLY_ABORTED)) {
+		trace_rxrpc_abort(0, why, sp->hdr.cid, sp->hdr.callNumber,
+				  sp->hdr.seq, abort_code, err);
+		rxrpc_poke_conn(conn, rxrpc_conn_get_poke_abort);
+	}
+	return -EPROTO;
+}
+
+/*
+ * Mark a connection as being remotely aborted.
+ */
+static bool rxrpc_input_conn_abort(struct rxrpc_connection *conn,
+				   struct sk_buff *skb)
+{
+	return rxrpc_set_conn_aborted(conn, skb, skb->priority, -ECONNABORTED,
+				      RXRPC_CALL_REMOTELY_ABORTED);
+}
+
+/*
  * Retransmit terminal ACK or ABORT of the previous call.
  */
 void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
@@ -146,9 +200,7 @@ void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
 /*
  * pass a connection-level abort onto all calls on that connection
  */
-static void rxrpc_abort_calls(struct rxrpc_connection *conn,
-			      enum rxrpc_call_completion compl,
-			      rxrpc_serial_t serial)
+static void rxrpc_abort_calls(struct rxrpc_connection *conn)
 {
 	struct rxrpc_call *call;
 	int i;
@@ -161,20 +213,11 @@ static void rxrpc_abort_calls(struct rxrpc_connection *conn,
 		call = rcu_dereference_protected(
 			conn->channels[i].call,
 			lockdep_is_held(&conn->bundle->channel_lock));
-		if (call) {
-			if (compl == RXRPC_CALL_LOCALLY_ABORTED)
-				trace_rxrpc_abort(call->debug_id,
-						  "CON", call->cid,
-						  call->call_id, 0,
-						  conn->abort_code,
-						  conn->error);
-			else
-				trace_rxrpc_rx_abort(call, serial,
-						     conn->abort_code);
-			rxrpc_set_call_completion(call, compl,
+		if (call)
+			rxrpc_set_call_completion(call,
+						  conn->completion,
 						  conn->abort_code,
 						  conn->error);
-		}
 	}
 
 	spin_unlock(&conn->bundle->channel_lock);
@@ -182,82 +225,6 @@ static void rxrpc_abort_calls(struct rxrpc_connection *conn,
 }
 
 /*
- * generate a connection-level abort
- */
-static int rxrpc_abort_connection(struct rxrpc_connection *conn,
-				  int error, u32 abort_code)
-{
-	struct rxrpc_wire_header whdr;
-	struct msghdr msg;
-	struct kvec iov[2];
-	__be32 word;
-	size_t len;
-	u32 serial;
-	int ret;
-
-	_enter("%d,,%u,%u", conn->debug_id, error, abort_code);
-
-	/* generate a connection-level abort */
-	spin_lock(&conn->state_lock);
-	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
-		spin_unlock(&conn->state_lock);
-		_leave(" = 0 [already dead]");
-		return 0;
-	}
-
-	conn->error = error;
-	conn->abort_code = abort_code;
-	conn->state = RXRPC_CONN_LOCALLY_ABORTED;
-	set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
-	spin_unlock(&conn->state_lock);
-
-	msg.msg_name	= &conn->peer->srx.transport;
-	msg.msg_namelen	= conn->peer->srx.transport_len;
-	msg.msg_control	= NULL;
-	msg.msg_controllen = 0;
-	msg.msg_flags	= 0;
-
-	whdr.epoch	= htonl(conn->proto.epoch);
-	whdr.cid	= htonl(conn->proto.cid);
-	whdr.callNumber	= 0;
-	whdr.seq	= 0;
-	whdr.type	= RXRPC_PACKET_TYPE_ABORT;
-	whdr.flags	= conn->out_clientflag;
-	whdr.userStatus	= 0;
-	whdr.securityIndex = conn->security_ix;
-	whdr._rsvd	= 0;
-	whdr.serviceId	= htons(conn->service_id);
-
-	word		= htonl(conn->abort_code);
-
-	iov[0].iov_base	= &whdr;
-	iov[0].iov_len	= sizeof(whdr);
-	iov[1].iov_base	= &word;
-	iov[1].iov_len	= sizeof(word);
-
-	len = iov[0].iov_len + iov[1].iov_len;
-
-	serial = atomic_inc_return(&conn->serial);
-	rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, serial);
-	whdr.serial = htonl(serial);
-
-	ret = kernel_sendmsg(conn->local->socket, &msg, iov, 2, len);
-	if (ret < 0) {
-		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
-				    rxrpc_tx_point_conn_abort);
-		_debug("sendmsg failed: %d", ret);
-		return -EAGAIN;
-	}
-
-	trace_rxrpc_tx_packet(conn->debug_id, &whdr, rxrpc_tx_point_conn_abort);
-
-	conn->peer->last_tx_at = ktime_get_seconds();
-
-	_leave(" = 0");
-	return 0;
-}
-
-/*
  * mark a call as being on a now-secured channel
  * - must be called with BH's disabled.
  */
@@ -278,26 +245,22 @@ static void rxrpc_call_is_secure(struct rxrpc_call *call)
  * connection-level Rx packet processor
  */
 static int rxrpc_process_event(struct rxrpc_connection *conn,
-			       struct sk_buff *skb,
-			       u32 *_abort_code)
+			       struct sk_buff *skb)
 {
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 	int loop, ret;
 
-	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
-		_leave(" = -ECONNABORTED [%u]", conn->state);
+	if (conn->state == RXRPC_CONN_ABORTED)
 		return -ECONNABORTED;
-	}
 
 	_enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial);
 
 	switch (sp->hdr.type) {
 	case RXRPC_PACKET_TYPE_CHALLENGE:
-		return conn->security->respond_to_challenge(conn, skb,
-							    _abort_code);
+		return conn->security->respond_to_challenge(conn, skb);
 
 	case RXRPC_PACKET_TYPE_RESPONSE:
-		ret = conn->security->verify_response(conn, skb, _abort_code);
+		ret = conn->security->verify_response(conn, skb);
 		if (ret < 0)
 			return ret;
 
@@ -336,26 +299,8 @@ static int rxrpc_process_event(struct rxrpc_connection *conn,
  */
 static void rxrpc_secure_connection(struct rxrpc_connection *conn)
 {
-	u32 abort_code;
-	int ret;
-
-	_enter("{%d}", conn->debug_id);
-
-	ASSERT(conn->security_ix != 0);
-
-	if (conn->security->issue_challenge(conn) < 0) {
-		abort_code = RX_CALL_DEAD;
-		ret = -ENOMEM;
-		goto abort;
-	}
-
-	_leave("");
-	return;
-
-abort:
-	_debug("abort %d, %d", ret, abort_code);
-	rxrpc_abort_connection(conn, ret, abort_code);
-	_leave(" [aborted]");
+	if (conn->security->issue_challenge(conn) < 0)
+		rxrpc_abort_conn(conn, NULL, RX_CALL_DEAD, -ENOMEM, "OOM");
 }
 
 /*
@@ -406,7 +351,6 @@ again:
 static void rxrpc_do_process_connection(struct rxrpc_connection *conn)
 {
 	struct sk_buff *skb;
-	u32 abort_code = RX_PROTOCOL_ERROR;
 	int ret;
 
 	if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events))
@@ -416,33 +360,18 @@ static void rxrpc_do_process_connection(struct rxrpc_connection *conn)
 	 * connection that each one has when we've finished with it */
 	while ((skb = skb_dequeue(&conn->rx_queue))) {
 		rxrpc_see_skb(skb, rxrpc_skb_see_conn_work);
-		ret = rxrpc_process_event(conn, skb, &abort_code);
+		ret = rxrpc_process_event(conn, skb);
 		switch (ret) {
-		case -EPROTO:
-		case -EKEYEXPIRED:
-		case -EKEYREJECTED:
-			goto protocol_error;
 		case -ENOMEM:
 		case -EAGAIN:
-			goto requeue_and_leave;
-		case -ECONNABORTED:
+			skb_queue_head(&conn->rx_queue, skb);
+			rxrpc_queue_conn(conn, rxrpc_conn_queue_retry_work);
+			break;
 		default:
 			rxrpc_free_skb(skb, rxrpc_skb_put_conn_work);
 			break;
 		}
 	}
-
-	return;
-
-requeue_and_leave:
-	skb_queue_head(&conn->rx_queue, skb);
-	return;
-
-protocol_error:
-	if (rxrpc_abort_connection(conn, ret, abort_code) < 0)
-		goto requeue_and_leave;
-	rxrpc_free_skb(skb, rxrpc_skb_put_conn_work);
-	return;
 }
 
 void rxrpc_process_connection(struct work_struct *work)
@@ -480,28 +409,25 @@ int rxrpc_input_conn_packet(struct rxrpc_connection *conn, struct sk_buff *skb)
 {
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 
-	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
-		_leave(" = -ECONNABORTED [%u]", conn->state);
-		return 0;
-	}
-
-	_enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial);
-
 	switch (sp->hdr.type) {
 	case RXRPC_PACKET_TYPE_BUSY:
 		/* Just ignore BUSY packets for now. */
 		return 0;
 
 	case RXRPC_PACKET_TYPE_ABORT:
-		conn->error = -ECONNABORTED;
-		conn->abort_code = skb->priority;
-		conn->state = RXRPC_CONN_REMOTELY_ABORTED;
-		set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
-		rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED, sp->hdr.serial);
-		return 0;
+		if (rxrpc_is_conn_aborted(conn))
+			return true;
+		rxrpc_input_conn_abort(conn, skb);
+		rxrpc_abort_calls(conn);
+		return true;
 
 	case RXRPC_PACKET_TYPE_CHALLENGE:
 	case RXRPC_PACKET_TYPE_RESPONSE:
+		if (rxrpc_is_conn_aborted(conn)) {
+			if (conn->completion == RXRPC_CALL_LOCALLY_ABORTED)
+				rxrpc_send_conn_abort(conn);
+			return true;
+		}
 		rxrpc_post_packet_to_conn(conn, skb);
 		return 0;
 
@@ -517,6 +443,9 @@ int rxrpc_input_conn_packet(struct rxrpc_connection *conn, struct sk_buff *skb)
  */
 void rxrpc_input_conn_event(struct rxrpc_connection *conn, struct sk_buff *skb)
 {
+	if (test_and_clear_bit(RXRPC_CONN_EV_ABORT_CALLS, &conn->events))
+		rxrpc_abort_calls(conn);
+
 	/* Process delayed ACKs whose time has come. */
 	if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
 		rxrpc_process_delayed_final_acks(conn, false);