2 /* incoming call handling
26  * Preallocate a single service call, connection and peer and, if possible,
37 	struct rxrpc_call *call;  in rxrpc_service_prealloc_one()  local
94 	call = rxrpc_alloc_call(rx, gfp, debug_id);  in rxrpc_service_prealloc_one()
95 	if (!call)  in rxrpc_service_prealloc_one()
97 	call->flags |= (1 << RXRPC_CALL_IS_SERVICE);  in rxrpc_service_prealloc_one()
98 	call->state = RXRPC_CALL_SERVER_PREALLOC;  in rxrpc_service_prealloc_one()
100 	trace_rxrpc_call(call->debug_id, rxrpc_call_new_service,  in rxrpc_service_prealloc_one()
101 			 atomic_read(&call->usage),  in rxrpc_service_prealloc_one()
123 		call->user_call_ID = user_call_ID;  in rxrpc_service_prealloc_one()
124 		call->notify_rx = notify_rx;  in rxrpc_service_prealloc_one()
125 		rxrpc_get_call(call, rxrpc_call_got_kernel);  in rxrpc_service_prealloc_one()
126 		user_attach_call(call, user_call_ID);  in rxrpc_service_prealloc_one()
127 		rxrpc_get_call(call, rxrpc_call_got_userid);  in rxrpc_service_prealloc_one()
128 		rb_link_node(&call->sock_node, parent, pp);  in rxrpc_service_prealloc_one()
129 		rb_insert_color(&call->sock_node, &rx->calls);  in rxrpc_service_prealloc_one()
130 		set_bit(RXRPC_CALL_HAS_USERID, &call->flags);  in rxrpc_service_prealloc_one()
133 	list_add(&call->sock_link, &rx->sock_calls);  in rxrpc_service_prealloc_one()
137 	rxnet = call->rxnet;  in rxrpc_service_prealloc_one()
139 	list_add_tail(&call->link, &rxnet->calls);  in rxrpc_service_prealloc_one()
142 	b->call_backlog[call_head] = call;  in rxrpc_service_prealloc_one()
144 	_leave(" = 0 [%d -> %lx]", call->debug_id, user_call_ID);  in rxrpc_service_prealloc_one()
149 	rxrpc_cleanup_call(call);  in rxrpc_service_prealloc_one()
156  * entire backlog of a socket.  When a new call comes in, if we don't have
157  * sufficient of each available, the call gets rejected as busy or ignored.
226 		struct rxrpc_call *call = b->call_backlog[tail];  in rxrpc_discard_prealloc()  local
227 		rcu_assign_pointer(call->socket, rx);  in rxrpc_discard_prealloc()
229 			_debug("discard %lx", call->user_call_ID);  in rxrpc_discard_prealloc()
230 			rx->discard_new_call(call, call->user_call_ID);  in rxrpc_discard_prealloc()
231 			rxrpc_put_call(call, rxrpc_call_put_kernel);  in rxrpc_discard_prealloc()
233 		rxrpc_call_completed(call);  in rxrpc_discard_prealloc()
234 		rxrpc_release_call(rx, call);  in rxrpc_discard_prealloc()
235 		rxrpc_put_call(call, rxrpc_call_put);  in rxrpc_discard_prealloc()
243  * Allocate a new incoming call from the prealloc pool, along with a connection
253 	struct rxrpc_call *call;  in rxrpc_alloc_incoming_call()  local
302 	/* And now we can allocate and set up a new call */  in rxrpc_alloc_incoming_call()
303 	call = b->call_backlog[call_tail];  in rxrpc_alloc_incoming_call()
308 	rxrpc_see_call(call);  in rxrpc_alloc_incoming_call()
309 	call->conn = conn;  in rxrpc_alloc_incoming_call()
310 	call->security = conn->security;  in rxrpc_alloc_incoming_call()
311 	call->peer = rxrpc_get_peer(conn->params.peer);  in rxrpc_alloc_incoming_call()
312 	call->cong_cwnd = call->peer->cong_cwnd;  in rxrpc_alloc_incoming_call()
313 	return call;  in rxrpc_alloc_incoming_call()
317  * Set up a new incoming call.  Called in BH context with the RCU read lock
320  * If this is for a kernel service, when we allocate the call, it will have
329  * The call is returned with the user access mutex held.
338 	struct rxrpc_call *call;  in rxrpc_new_incoming_call()  local
350 		call = NULL;  in rxrpc_new_incoming_call()
354 	/* The peer, connection and call may all have sprung into existence due  in rxrpc_new_incoming_call()
361 	call = rxrpc_alloc_incoming_call(rx, local, peer, conn, skb);  in rxrpc_new_incoming_call()
362 	if (!call) {  in rxrpc_new_incoming_call()
365 		call = NULL;  in rxrpc_new_incoming_call()
369 	trace_rxrpc_receive(call, rxrpc_receive_incoming,  in rxrpc_new_incoming_call()
372 	/* Lock the call to prevent rxrpc_kernel_send/recv_data() and  in rxrpc_new_incoming_call()
377 	 * behaved enough not to access the call before the first notification  in rxrpc_new_incoming_call()
381 	if (!mutex_trylock(&call->user_mutex))  in rxrpc_new_incoming_call()
384 	/* Make the call live. */  in rxrpc_new_incoming_call()
385 	rxrpc_incoming_call(rx, call, skb);  in rxrpc_new_incoming_call()
386 	conn = call->conn;  in rxrpc_new_incoming_call()
389 		rx->notify_new_call(&rx->sk, call, call->user_call_ID);  in rxrpc_new_incoming_call()
397 		set_bit(RXRPC_CONN_EV_CHALLENGE, &call->conn->events);  in rxrpc_new_incoming_call()
398 		rxrpc_queue_conn(call->conn);  in rxrpc_new_incoming_call()
402 		write_lock(&call->state_lock);  in rxrpc_new_incoming_call()
403 		if (call->state < RXRPC_CALL_COMPLETE) {  in rxrpc_new_incoming_call()
405 				call->state = RXRPC_CALL_SERVER_RECV_REQUEST;  in rxrpc_new_incoming_call()
407 				call->state = RXRPC_CALL_SERVER_ACCEPTING;  in rxrpc_new_incoming_call()
409 		write_unlock(&call->state_lock);  in rxrpc_new_incoming_call()
413 		rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED,  in rxrpc_new_incoming_call()
417 		rxrpc_abort_call("CON", call, sp->hdr.seq,  in rxrpc_new_incoming_call()
425 	if (call->state == RXRPC_CALL_SERVER_ACCEPTING)  in rxrpc_new_incoming_call()
426 		rxrpc_notify_socket(call);  in rxrpc_new_incoming_call()
431 	 * service to prevent the call from being deallocated too early.  in rxrpc_new_incoming_call()
433 	rxrpc_put_call(call, rxrpc_call_put);  in rxrpc_new_incoming_call()
435 	_leave(" = %p{%d}", call, call->debug_id);  in rxrpc_new_incoming_call()
438 	return call;  in rxrpc_new_incoming_call()
442  * handle acceptance of a call by userspace
443  * - assign the user call ID to the call at the front of the queue
450 	__acquires(call->user_mutex)  in rxrpc_accept_call()
452 	struct rxrpc_call *call;  in rxrpc_accept_call()  local
474 		call = rb_entry(parent, struct rxrpc_call, sock_node);  in rxrpc_accept_call()
476 		if (user_call_ID < call->user_call_ID)  in rxrpc_accept_call()
478 		else if (user_call_ID > call->user_call_ID)  in rxrpc_accept_call()
484 	/* Dequeue the first call and check it's still valid.  We gain  in rxrpc_accept_call()
487 	call = list_entry(rx->to_be_accepted.next,  in rxrpc_accept_call()
496 	if (mutex_lock_interruptible(&call->user_mutex) < 0) {  in rxrpc_accept_call()
503 	list_del_init(&call->accept_link);  in rxrpc_accept_call()
505 	rxrpc_see_call(call);  in rxrpc_accept_call()
512 		call = rb_entry(parent, struct rxrpc_call, sock_node);  in rxrpc_accept_call()
514 		if (user_call_ID < call->user_call_ID)  in rxrpc_accept_call()
516 		else if (user_call_ID > call->user_call_ID)  in rxrpc_accept_call()
522 	write_lock_bh(&call->state_lock);  in rxrpc_accept_call()
523 	switch (call->state) {  in rxrpc_accept_call()
525 		call->state = RXRPC_CALL_SERVER_RECV_REQUEST;  in rxrpc_accept_call()
528 		ret = call->error;  in rxrpc_accept_call()
535 	call->notify_rx = notify_rx;  in rxrpc_accept_call()
536 	call->user_call_ID = user_call_ID;  in rxrpc_accept_call()
537 	rxrpc_get_call(call, rxrpc_call_got_userid);  in rxrpc_accept_call()
538 	rb_link_node(&call->sock_node, parent, pp);  in rxrpc_accept_call()
539 	rb_insert_color(&call->sock_node, &rx->calls);  in rxrpc_accept_call()
540 	if (test_and_set_bit(RXRPC_CALL_HAS_USERID, &call->flags))  in rxrpc_accept_call()
543 	write_unlock_bh(&call->state_lock);  in rxrpc_accept_call()
545 	rxrpc_notify_socket(call);  in rxrpc_accept_call()
548 	_leave(" = %p{%d}", call, call->debug_id);  in rxrpc_accept_call()
549 	return call;  in rxrpc_accept_call()
552 	_debug("release %p", call);  in rxrpc_accept_call()
553 	write_unlock_bh(&call->state_lock);  in rxrpc_accept_call()
555 	rxrpc_release_call(rx, call);  in rxrpc_accept_call()
556 	rxrpc_put_call(call, rxrpc_call_put);  in rxrpc_accept_call()
570  * Handle rejection of a call by userspace
571  * - reject the call at the front of the queue
575 	struct rxrpc_call *call;  in rxrpc_reject_call()  local
590 	/* Dequeue the first call and check it's still valid.  We gain  in rxrpc_reject_call()
593 	call = list_entry(rx->to_be_accepted.next,  in rxrpc_reject_call()
595 	list_del_init(&call->accept_link);  in rxrpc_reject_call()
597 	rxrpc_see_call(call);  in rxrpc_reject_call()
599 	write_lock_bh(&call->state_lock);  in rxrpc_reject_call()
600 	switch (call->state) {  in rxrpc_reject_call()
602 		__rxrpc_abort_call("REJ", call, 1, RX_USER_ABORT, -ECONNABORTED);  in rxrpc_reject_call()
606 		ret = call->error;  in rxrpc_reject_call()
613 	write_unlock_bh(&call->state_lock);  in rxrpc_reject_call()
616 		rxrpc_send_abort_packet(call);  in rxrpc_reject_call()
617 		rxrpc_release_call(rx, call);  in rxrpc_reject_call()
618 		rxrpc_put_call(call, rxrpc_call_put);  in rxrpc_reject_call()
628  * @notify_rx: Event notification function for the call
629  * @user_attach_call: Func to attach call to user_call_ID
630  * @user_call_ID: The tag to attach to the preallocated call
636  * The user is given a ref to hold on the call.
638  * Note that the call may be come connected before this function returns.