Revert "rxrpc: Allow failed client calls to be retried"

The changes introduced to allow rxrpc calls to be retried creates an issue
when it comes to refcounting afs_call structs.  The problem is that when
rxrpc_send_data() queues the last packet for an asynchronous call, the
following sequence can occur:

 (1) The notify_end_tx callback is invoked which causes the state in the
     afs_call to be changed from AFS_CALL_CL_REQUESTING or
     AFS_CALL_SV_REPLYING.

 (2) afs_deliver_to_call() can then process event notifications from rxrpc
     on the async_work queue.

 (3) Delivery of events, such as an abort from the server, can cause the
     afs_call state to be changed to AFS_CALL_COMPLETE on async_work.

 (4) For an asynchronous call, afs_process_async_call() notes that the call
     is complete and tried to clean up all the refs on async_work.

 (5) rxrpc_send_data() might return the amount of data transferred
     (success) or an error - which could in turn reflect a local error or a
     received error.

Synchronising the clean up after rxrpc_kernel_send_data() returns an error
with the asynchronous cleanup is then tricky to get right.

Mostly revert commit c038a58ccfd6704d4d7d60ed3d6a0fca13cf13a4.  The two API
functions the original commit added aren't currently used.  This makes
rxrpc_kernel_send_data() always return successfully if it queued the data
it was given.

Note that this doesn't affect synchronous calls since their Rx notification
function merely pokes a wait queue and does not refcounting.  The
asynchronous call notification function *has* to do refcounting and pass a
ref over the work item to avoid the need to sync the workqueue in call
cleanup.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 7 deletions

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index bc628acf4f4f..4b1a534d290a 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -476,7 +476,6 @@ enum rxrpc_call_flag {
 	RXRPC_CALL_EXPOSED,		/* The call was exposed to the world */
 	RXRPC_CALL_RX_LAST,		/* Received the last packet (at rxtx_top) */
 	RXRPC_CALL_TX_LAST,		/* Last packet in Tx buffer (at rxtx_top) */
-	RXRPC_CALL_TX_LASTQ,		/* Last packet has been queued */
 	RXRPC_CALL_SEND_PING,		/* A ping will need to be sent */
 	RXRPC_CALL_PINGING,		/* Ping in process */
 	RXRPC_CALL_RETRANS_TIMEOUT,	/* Retransmission due to timeout occurred */
@@ -518,6 +517,18 @@ enum rxrpc_call_state {
 };
 
 /*
+ * Call completion condition (state == RXRPC_CALL_COMPLETE).
+ */
+enum rxrpc_call_completion {
+	RXRPC_CALL_SUCCEEDED,		/* - Normal termination */
+	RXRPC_CALL_REMOTELY_ABORTED,	/* - call aborted by peer */
+	RXRPC_CALL_LOCALLY_ABORTED,	/* - call aborted locally on error or close */
+	RXRPC_CALL_LOCAL_ERROR,		/* - call failed due to local error */
+	RXRPC_CALL_NETWORK_ERROR,	/* - call terminated by network error */
+	NR__RXRPC_CALL_COMPLETIONS
+};
+
+/*
  * Call Tx congestion management modes.
  */
 enum rxrpc_congest_mode {
@@ -761,15 +772,9 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *,
 					 struct sockaddr_rxrpc *,
 					 struct rxrpc_call_params *, gfp_t,
 					 unsigned int);
-int rxrpc_retry_client_call(struct rxrpc_sock *,
-			    struct rxrpc_call *,
-			    struct rxrpc_conn_parameters *,
-			    struct sockaddr_rxrpc *,
-			    gfp_t);
 void rxrpc_incoming_call(struct rxrpc_sock *, struct rxrpc_call *,
 			 struct sk_buff *);
 void rxrpc_release_call(struct rxrpc_sock *, struct rxrpc_call *);
-int rxrpc_prepare_call_for_retry(struct rxrpc_sock *, struct rxrpc_call *);
 void rxrpc_release_calls_on_socket(struct rxrpc_sock *);
 bool __rxrpc_queue_call(struct rxrpc_call *);
 bool rxrpc_queue_call(struct rxrpc_call *);