rxrpc: Tidy up abort generation infrastructure

Tidy up the abort generation infrastructure in the following ways:

 (1) Create an enum and string mapping table to list the reasons an abort
     might be generated in tracing.

 (2) Replace the 3-char string with the values from (1) in the places that
     use that to log the abort source.  This gets rid of a memcpy() in the
     tracepoint.

 (3) Subsume the rxrpc_rx_eproto tracepoint with the rxrpc_abort tracepoint
     and use values from (1) to indicate the trace reason.

 (4) Always make a call to an abort function at the point of the abort
     rather than stashing the values into variables and using goto to get
     to a place where it reported.  The C optimiser will collapse the calls
     together as appropriate.  The abort functions return a value that can
     be returned directly if appropriate.

Note that this extends into afs also at the points where that generates an
abort.  To aid with this, the afs sources need to #define
RXRPC_TRACE_ONLY_DEFINE_ENUMS before including the rxrpc tracing header
because they don't have access to the rxrpc internal structures that some
of the tracepoints make use of.

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

1 files changed, 29 insertions, 22 deletions

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 78bd6fb0bc15..120ce3ccbb22 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -627,9 +627,10 @@ struct rxrpc_call {
 	unsigned long		events;
 	spinlock_t		notify_lock;	/* Kernel notification lock */
 	rwlock_t		state_lock;	/* lock for state transition */
-	const char		*send_abort_why; /* String indicating why the abort was sent */
+	unsigned int		send_abort_why; /* Why the abort [enum rxrpc_abort_reason] */
 	s32			send_abort;	/* Abort code to be sent */
 	short			send_abort_err;	/* Error to be associated with the abort */
+	rxrpc_seq_t		send_abort_seq;	/* DATA packet that incurred the abort (or 0) */
 	s32			abort_code;	/* Local/remote abort code */
 	int			error;		/* Local error incurred */
 	enum rxrpc_call_state	state;		/* current state of call */
@@ -818,9 +819,11 @@ extern struct workqueue_struct *rxrpc_workqueue;
  */
 int rxrpc_service_prealloc(struct rxrpc_sock *, gfp_t);
 void rxrpc_discard_prealloc(struct rxrpc_sock *);
-int rxrpc_new_incoming_call(struct rxrpc_local *, struct rxrpc_peer *,
-			    struct rxrpc_connection *, struct sockaddr_rxrpc *,
-			    struct sk_buff *);
+bool rxrpc_new_incoming_call(struct rxrpc_local *local,
+			     struct rxrpc_peer *peer,
+			     struct rxrpc_connection *conn,
+			     struct sockaddr_rxrpc *peer_srx,
+			     struct sk_buff *skb);
 void rxrpc_accept_incoming_calls(struct rxrpc_local *);
 int rxrpc_user_charge_accept(struct rxrpc_sock *, unsigned long);
 
@@ -840,7 +843,7 @@ void rxrpc_reduce_call_timer(struct rxrpc_call *call,
 			     unsigned long now,
 			     enum rxrpc_timer_trace why);
 
-void rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb);
+bool rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb);
 
 /*
  * call_object.c
@@ -905,10 +908,10 @@ void rxrpc_clean_up_local_conns(struct rxrpc_local *);
 void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn, struct sk_buff *skb,
 				unsigned int channel);
 int rxrpc_abort_conn(struct rxrpc_connection *conn, struct sk_buff *skb,
-		     s32 abort_code, int err, const char *why);
+		     s32 abort_code, int err, enum rxrpc_abort_reason why);
 void rxrpc_process_connection(struct work_struct *);
 void rxrpc_process_delayed_final_acks(struct rxrpc_connection *, bool);
-int rxrpc_input_conn_packet(struct rxrpc_connection *conn, struct sk_buff *skb);
+bool 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);
 
 static inline bool rxrpc_is_conn_aborted(const struct rxrpc_connection *conn)
@@ -979,12 +982,19 @@ void rxrpc_implicit_end_call(struct rxrpc_call *, struct sk_buff *);
  */
 int rxrpc_encap_rcv(struct sock *, struct sk_buff *);
 void rxrpc_error_report(struct sock *);
+bool rxrpc_direct_abort(struct sk_buff *skb, enum rxrpc_abort_reason why,
+			s32 abort_code, int err);
 int rxrpc_io_thread(void *data);
 static inline void rxrpc_wake_up_io_thread(struct rxrpc_local *local)
 {
 	wake_up_process(local->io_thread);
 }
 
+static inline bool rxrpc_protocol_error(struct sk_buff *skb, enum rxrpc_abort_reason why)
+{
+	return rxrpc_direct_abort(skb, why, RX_PROTOCOL_ERROR, -EPROTO);
+}
+
 /*
  * insecure.c
  */
@@ -1108,29 +1118,26 @@ bool __rxrpc_set_call_completion(struct rxrpc_call *, enum rxrpc_call_completion
 bool rxrpc_set_call_completion(struct rxrpc_call *, enum rxrpc_call_completion, u32, int);
 bool __rxrpc_call_completed(struct rxrpc_call *);
 bool rxrpc_call_completed(struct rxrpc_call *);
-bool __rxrpc_abort_call(const char *, struct rxrpc_call *, rxrpc_seq_t, u32, int);
-bool rxrpc_abort_call(const char *, struct rxrpc_call *, rxrpc_seq_t, u32, int);
+bool __rxrpc_abort_call(struct rxrpc_call *call, rxrpc_seq_t seq,
+			u32 abort_code, int error, enum rxrpc_abort_reason why);
+bool rxrpc_abort_call(struct rxrpc_call *call, rxrpc_seq_t seq,
+		      u32 abort_code, int error, enum rxrpc_abort_reason why);
 int rxrpc_recvmsg(struct socket *, struct msghdr *, size_t, int);
 
 /*
  * Abort a call due to a protocol error.
  */
-static inline bool __rxrpc_abort_eproto(struct rxrpc_call *call,
-					struct sk_buff *skb,
-					const char *eproto_why,
-					const char *why,
-					u32 abort_code)
+static inline int rxrpc_abort_eproto(struct rxrpc_call *call,
+				     struct sk_buff *skb,
+				     s32 abort_code,
+				     enum rxrpc_abort_reason why)
 {
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 
-	trace_rxrpc_rx_eproto(call, sp->hdr.serial, eproto_why);
-	return rxrpc_abort_call(why, call, sp->hdr.seq, abort_code, -EPROTO);
+	rxrpc_abort_call(call, sp->hdr.seq, abort_code, -EPROTO, why);
+	return -EPROTO;
 }
 
-#define rxrpc_abort_eproto(call, skb, eproto_why, abort_why, abort_code) \
-	__rxrpc_abort_eproto((call), (skb), tracepoint_string(eproto_why), \
-			     (abort_why), (abort_code))
-
 /*
  * rtt.c
  */
@@ -1162,8 +1169,8 @@ struct key *rxrpc_look_up_server_security(struct rxrpc_connection *,
 /*
  * sendmsg.c
  */
-bool rxrpc_propose_abort(struct rxrpc_call *call,
-			 u32 abort_code, int error, const char *why);
+bool rxrpc_propose_abort(struct rxrpc_call *call, s32 abort_code, int error,
+			 enum rxrpc_abort_reason why);
 int rxrpc_do_sendmsg(struct rxrpc_sock *, struct msghdr *, size_t);
 
 /*