rxrpc: Only set/transmit aborts in the I/O thread

Only set the abort call completion state in the I/O thread and only
transmit ABORT packets from there.  rxrpc_abort_call() can then be made to
actually send the packet.

Further, ABORT packets should only be sent if the call has been exposed to
the network (ie. at least one attempted DATA transmission has occurred for
it).

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

1 files changed, 22 insertions, 7 deletions

diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index cde1e65f16b4..dc3c2a834fc8 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -18,6 +18,26 @@
 #include "ar-internal.h"
 
 /*
+ * Propose an abort to be made in the I/O thread.
+ */
+bool rxrpc_propose_abort(struct rxrpc_call *call,
+			 u32 abort_code, int error, const char *why)
+{
+	_enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
+
+	if (!call->send_abort && call->state < RXRPC_CALL_COMPLETE) {
+		call->send_abort_why = why;
+		call->send_abort_err = error;
+		/* Request abort locklessly vs rxrpc_input_call_event(). */
+		smp_store_release(&call->send_abort, abort_code);
+		rxrpc_poke_call(call, rxrpc_call_poke_abort);
+		return true;
+	}
+
+	return false;
+}
+
+/*
  * Return true if there's sufficient Tx queue space.
  */
 static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
@@ -663,9 +683,8 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 		/* it's too late for this call */
 		ret = -ESHUTDOWN;
 	} else if (p.command == RXRPC_CMD_SEND_ABORT) {
+		rxrpc_propose_abort(call, p.abort_code, -ECONNABORTED, "CMD");
 		ret = 0;
-		if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
-			ret = rxrpc_send_abort_packet(call);
 	} else if (p.command != RXRPC_CMD_SEND_DATA) {
 		ret = -EINVAL;
 	} else {
@@ -760,11 +779,7 @@ bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
 	_enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
 
 	mutex_lock(&call->user_mutex);
-
-	aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
-	if (aborted)
-		rxrpc_send_abort_packet(call);
-
+	aborted = rxrpc_propose_abort(call, abort_code, error, why);
 	mutex_unlock(&call->user_mutex);
 	return aborted;
 }