xref: /openbmc/linux/net/rxrpc/sendmsg.c (revision a266ef69)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* AF_RXRPC sendmsg() implementation.
3  *
4  * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/net.h>
11 #include <linux/gfp.h>
12 #include <linux/skbuff.h>
13 #include <linux/export.h>
14 #include <linux/sched/signal.h>
15 
16 #include <net/sock.h>
17 #include <net/af_rxrpc.h>
18 #include "ar-internal.h"
19 
20 /*
21  * Propose an abort to be made in the I/O thread.
22  */
23 bool rxrpc_propose_abort(struct rxrpc_call *call, s32 abort_code, int error,
24 			 enum rxrpc_abort_reason why)
25 {
26 	_enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
27 
28 	if (!call->send_abort && !rxrpc_call_is_complete(call)) {
29 		call->send_abort_why = why;
30 		call->send_abort_err = error;
31 		call->send_abort_seq = 0;
32 		/* Request abort locklessly vs rxrpc_input_call_event(). */
33 		smp_store_release(&call->send_abort, abort_code);
34 		rxrpc_poke_call(call, rxrpc_call_poke_abort);
35 		return true;
36 	}
37 
38 	return false;
39 }
40 
41 /*
42  * Wait for a call to become connected.  Interruption here doesn't cause the
43  * call to be aborted.
44  */
45 static int rxrpc_wait_to_be_connected(struct rxrpc_call *call, long *timeo)
46 {
47 	DECLARE_WAITQUEUE(myself, current);
48 	int ret = 0;
49 
50 	_enter("%d", call->debug_id);
51 
52 	if (rxrpc_call_state(call) != RXRPC_CALL_CLIENT_AWAIT_CONN)
53 		return call->error;
54 
55 	add_wait_queue_exclusive(&call->waitq, &myself);
56 
57 	for (;;) {
58 		ret = call->error;
59 		if (ret < 0)
60 			break;
61 
62 		switch (call->interruptibility) {
63 		case RXRPC_INTERRUPTIBLE:
64 		case RXRPC_PREINTERRUPTIBLE:
65 			set_current_state(TASK_INTERRUPTIBLE);
66 			break;
67 		case RXRPC_UNINTERRUPTIBLE:
68 		default:
69 			set_current_state(TASK_UNINTERRUPTIBLE);
70 			break;
71 		}
72 		if (rxrpc_call_state(call) != RXRPC_CALL_CLIENT_AWAIT_CONN) {
73 			ret = call->error;
74 			break;
75 		}
76 		if ((call->interruptibility == RXRPC_INTERRUPTIBLE ||
77 		     call->interruptibility == RXRPC_PREINTERRUPTIBLE) &&
78 		    signal_pending(current)) {
79 			ret = sock_intr_errno(*timeo);
80 			break;
81 		}
82 		*timeo = schedule_timeout(*timeo);
83 	}
84 
85 	remove_wait_queue(&call->waitq, &myself);
86 	__set_current_state(TASK_RUNNING);
87 
88 	if (ret == 0 && rxrpc_call_is_complete(call))
89 		ret = call->error;
90 
91 	_leave(" = %d", ret);
92 	return ret;
93 }
94 
95 /*
96  * Return true if there's sufficient Tx queue space.
97  */
98 static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
99 {
100 	if (_tx_win)
101 		*_tx_win = call->tx_bottom;
102 	return call->tx_prepared - call->tx_bottom < 256;
103 }
104 
105 /*
106  * Wait for space to appear in the Tx queue or a signal to occur.
107  */
108 static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
109 					 struct rxrpc_call *call,
110 					 long *timeo)
111 {
112 	for (;;) {
113 		set_current_state(TASK_INTERRUPTIBLE);
114 		if (rxrpc_check_tx_space(call, NULL))
115 			return 0;
116 
117 		if (rxrpc_call_is_complete(call))
118 			return call->error;
119 
120 		if (signal_pending(current))
121 			return sock_intr_errno(*timeo);
122 
123 		trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
124 		*timeo = schedule_timeout(*timeo);
125 	}
126 }
127 
128 /*
129  * Wait for space to appear in the Tx queue uninterruptibly, but with
130  * a timeout of 2*RTT if no progress was made and a signal occurred.
131  */
132 static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
133 					    struct rxrpc_call *call)
134 {
135 	rxrpc_seq_t tx_start, tx_win;
136 	signed long rtt, timeout;
137 
138 	rtt = READ_ONCE(call->peer->srtt_us) >> 3;
139 	rtt = usecs_to_jiffies(rtt) * 2;
140 	if (rtt < 2)
141 		rtt = 2;
142 
143 	timeout = rtt;
144 	tx_start = smp_load_acquire(&call->acks_hard_ack);
145 
146 	for (;;) {
147 		set_current_state(TASK_UNINTERRUPTIBLE);
148 
149 		if (rxrpc_check_tx_space(call, &tx_win))
150 			return 0;
151 
152 		if (rxrpc_call_is_complete(call))
153 			return call->error;
154 
155 		if (timeout == 0 &&
156 		    tx_win == tx_start && signal_pending(current))
157 			return -EINTR;
158 
159 		if (tx_win != tx_start) {
160 			timeout = rtt;
161 			tx_start = tx_win;
162 		}
163 
164 		trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
165 		timeout = schedule_timeout(timeout);
166 	}
167 }
168 
169 /*
170  * Wait for space to appear in the Tx queue uninterruptibly.
171  */
172 static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
173 					    struct rxrpc_call *call,
174 					    long *timeo)
175 {
176 	for (;;) {
177 		set_current_state(TASK_UNINTERRUPTIBLE);
178 		if (rxrpc_check_tx_space(call, NULL))
179 			return 0;
180 
181 		if (rxrpc_call_is_complete(call))
182 			return call->error;
183 
184 		trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
185 		*timeo = schedule_timeout(*timeo);
186 	}
187 }
188 
189 /*
190  * wait for space to appear in the transmit/ACK window
191  * - caller holds the socket locked
192  */
193 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
194 				    struct rxrpc_call *call,
195 				    long *timeo,
196 				    bool waitall)
197 {
198 	DECLARE_WAITQUEUE(myself, current);
199 	int ret;
200 
201 	_enter(",{%u,%u,%u,%u}",
202 	       call->tx_bottom, call->acks_hard_ack, call->tx_top, call->tx_winsize);
203 
204 	add_wait_queue(&call->waitq, &myself);
205 
206 	switch (call->interruptibility) {
207 	case RXRPC_INTERRUPTIBLE:
208 		if (waitall)
209 			ret = rxrpc_wait_for_tx_window_waitall(rx, call);
210 		else
211 			ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
212 		break;
213 	case RXRPC_PREINTERRUPTIBLE:
214 	case RXRPC_UNINTERRUPTIBLE:
215 	default:
216 		ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
217 		break;
218 	}
219 
220 	remove_wait_queue(&call->waitq, &myself);
221 	set_current_state(TASK_RUNNING);
222 	_leave(" = %d", ret);
223 	return ret;
224 }
225 
226 /*
227  * Notify the owner of the call that the transmit phase is ended and the last
228  * packet has been queued.
229  */
230 static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
231 				rxrpc_notify_end_tx_t notify_end_tx)
232 {
233 	if (notify_end_tx)
234 		notify_end_tx(&rx->sk, call, call->user_call_ID);
235 }
236 
237 /*
238  * Queue a DATA packet for transmission, set the resend timeout and send
239  * the packet immediately.  Returns the error from rxrpc_send_data_packet()
240  * in case the caller wants to do something with it.
241  */
242 static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
243 			       struct rxrpc_txbuf *txb,
244 			       rxrpc_notify_end_tx_t notify_end_tx)
245 {
246 	rxrpc_seq_t seq = txb->seq;
247 	bool last = test_bit(RXRPC_TXBUF_LAST, &txb->flags), poke;
248 
249 	rxrpc_inc_stat(call->rxnet, stat_tx_data);
250 
251 	ASSERTCMP(txb->seq, ==, call->tx_prepared + 1);
252 
253 	/* We have to set the timestamp before queueing as the retransmit
254 	 * algorithm can see the packet as soon as we queue it.
255 	 */
256 	txb->last_sent = ktime_get_real();
257 
258 	if (last)
259 		trace_rxrpc_txqueue(call, rxrpc_txqueue_queue_last);
260 	else
261 		trace_rxrpc_txqueue(call, rxrpc_txqueue_queue);
262 
263 	/* Add the packet to the call's output buffer */
264 	spin_lock(&call->tx_lock);
265 	poke = list_empty(&call->tx_sendmsg);
266 	list_add_tail(&txb->call_link, &call->tx_sendmsg);
267 	call->tx_prepared = seq;
268 	if (last)
269 		rxrpc_notify_end_tx(rx, call, notify_end_tx);
270 	spin_unlock(&call->tx_lock);
271 
272 	if (poke)
273 		rxrpc_poke_call(call, rxrpc_call_poke_start);
274 }
275 
276 /*
277  * send data through a socket
278  * - must be called in process context
279  * - The caller holds the call user access mutex, but not the socket lock.
280  */
281 static int rxrpc_send_data(struct rxrpc_sock *rx,
282 			   struct rxrpc_call *call,
283 			   struct msghdr *msg, size_t len,
284 			   rxrpc_notify_end_tx_t notify_end_tx,
285 			   bool *_dropped_lock)
286 {
287 	struct rxrpc_txbuf *txb;
288 	struct sock *sk = &rx->sk;
289 	enum rxrpc_call_state state;
290 	long timeo;
291 	bool more = msg->msg_flags & MSG_MORE;
292 	int ret, copied = 0;
293 
294 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
295 
296 	ret = rxrpc_wait_to_be_connected(call, &timeo);
297 	if (ret < 0)
298 		return ret;
299 
300 	if (call->conn->state == RXRPC_CONN_CLIENT_UNSECURED) {
301 		ret = rxrpc_init_client_conn_security(call->conn);
302 		if (ret < 0)
303 			return ret;
304 	}
305 
306 	/* this should be in poll */
307 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
308 
309 reload:
310 	ret = -EPIPE;
311 	if (sk->sk_shutdown & SEND_SHUTDOWN)
312 		goto maybe_error;
313 	state = rxrpc_call_state(call);
314 	ret = -ESHUTDOWN;
315 	if (state >= RXRPC_CALL_COMPLETE)
316 		goto maybe_error;
317 	ret = -EPROTO;
318 	if (state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
319 	    state != RXRPC_CALL_SERVER_ACK_REQUEST &&
320 	    state != RXRPC_CALL_SERVER_SEND_REPLY) {
321 		/* Request phase complete for this client call */
322 		trace_rxrpc_abort(call->debug_id, rxrpc_sendmsg_late_send,
323 				  call->cid, call->call_id, call->rx_consumed,
324 				  0, -EPROTO);
325 		goto maybe_error;
326 	}
327 
328 	ret = -EMSGSIZE;
329 	if (call->tx_total_len != -1) {
330 		if (len - copied > call->tx_total_len)
331 			goto maybe_error;
332 		if (!more && len - copied != call->tx_total_len)
333 			goto maybe_error;
334 	}
335 
336 	txb = call->tx_pending;
337 	call->tx_pending = NULL;
338 	if (txb)
339 		rxrpc_see_txbuf(txb, rxrpc_txbuf_see_send_more);
340 
341 	do {
342 		if (!txb) {
343 			size_t remain, bufsize, chunk, offset;
344 
345 			_debug("alloc");
346 
347 			if (!rxrpc_check_tx_space(call, NULL))
348 				goto wait_for_space;
349 
350 			/* Work out the maximum size of a packet.  Assume that
351 			 * the security header is going to be in the padded
352 			 * region (enc blocksize), but the trailer is not.
353 			 */
354 			remain = more ? INT_MAX : msg_data_left(msg);
355 			ret = call->conn->security->how_much_data(call, remain,
356 								  &bufsize, &chunk, &offset);
357 			if (ret < 0)
358 				goto maybe_error;
359 
360 			_debug("SIZE: %zu/%zu @%zu", chunk, bufsize, offset);
361 
362 			/* create a buffer that we can retain until it's ACK'd */
363 			ret = -ENOMEM;
364 			txb = rxrpc_alloc_txbuf(call, RXRPC_PACKET_TYPE_DATA,
365 						GFP_KERNEL);
366 			if (!txb)
367 				goto maybe_error;
368 
369 			txb->offset = offset;
370 			txb->space -= offset;
371 			txb->space = min_t(size_t, chunk, txb->space);
372 		}
373 
374 		_debug("append");
375 
376 		/* append next segment of data to the current buffer */
377 		if (msg_data_left(msg) > 0) {
378 			size_t copy = min_t(size_t, txb->space, msg_data_left(msg));
379 
380 			_debug("add %zu", copy);
381 			if (!copy_from_iter_full(txb->data + txb->offset, copy,
382 						 &msg->msg_iter))
383 				goto efault;
384 			_debug("added");
385 			txb->space -= copy;
386 			txb->len += copy;
387 			txb->offset += copy;
388 			copied += copy;
389 			if (call->tx_total_len != -1)
390 				call->tx_total_len -= copy;
391 		}
392 
393 		/* check for the far side aborting the call or a network error
394 		 * occurring */
395 		if (rxrpc_call_is_complete(call))
396 			goto call_terminated;
397 
398 		/* add the packet to the send queue if it's now full */
399 		if (!txb->space ||
400 		    (msg_data_left(msg) == 0 && !more)) {
401 			if (msg_data_left(msg) == 0 && !more) {
402 				txb->wire.flags |= RXRPC_LAST_PACKET;
403 				__set_bit(RXRPC_TXBUF_LAST, &txb->flags);
404 			}
405 			else if (call->tx_top - call->acks_hard_ack <
406 				 call->tx_winsize)
407 				txb->wire.flags |= RXRPC_MORE_PACKETS;
408 
409 			ret = call->security->secure_packet(call, txb);
410 			if (ret < 0)
411 				goto out;
412 
413 			rxrpc_queue_packet(rx, call, txb, notify_end_tx);
414 			txb = NULL;
415 		}
416 	} while (msg_data_left(msg) > 0);
417 
418 success:
419 	ret = copied;
420 	if (rxrpc_call_is_complete(call) &&
421 	    call->error < 0)
422 		ret = call->error;
423 out:
424 	call->tx_pending = txb;
425 	_leave(" = %d", ret);
426 	return ret;
427 
428 call_terminated:
429 	rxrpc_put_txbuf(txb, rxrpc_txbuf_put_send_aborted);
430 	_leave(" = %d", call->error);
431 	return call->error;
432 
433 maybe_error:
434 	if (copied)
435 		goto success;
436 	goto out;
437 
438 efault:
439 	ret = -EFAULT;
440 	goto out;
441 
442 wait_for_space:
443 	ret = -EAGAIN;
444 	if (msg->msg_flags & MSG_DONTWAIT)
445 		goto maybe_error;
446 	mutex_unlock(&call->user_mutex);
447 	*_dropped_lock = true;
448 	ret = rxrpc_wait_for_tx_window(rx, call, &timeo,
449 				       msg->msg_flags & MSG_WAITALL);
450 	if (ret < 0)
451 		goto maybe_error;
452 	if (call->interruptibility == RXRPC_INTERRUPTIBLE) {
453 		if (mutex_lock_interruptible(&call->user_mutex) < 0) {
454 			ret = sock_intr_errno(timeo);
455 			goto maybe_error;
456 		}
457 	} else {
458 		mutex_lock(&call->user_mutex);
459 	}
460 	*_dropped_lock = false;
461 	goto reload;
462 }
463 
464 /*
465  * extract control messages from the sendmsg() control buffer
466  */
467 static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
468 {
469 	struct cmsghdr *cmsg;
470 	bool got_user_ID = false;
471 	int len;
472 
473 	if (msg->msg_controllen == 0)
474 		return -EINVAL;
475 
476 	for_each_cmsghdr(cmsg, msg) {
477 		if (!CMSG_OK(msg, cmsg))
478 			return -EINVAL;
479 
480 		len = cmsg->cmsg_len - sizeof(struct cmsghdr);
481 		_debug("CMSG %d, %d, %d",
482 		       cmsg->cmsg_level, cmsg->cmsg_type, len);
483 
484 		if (cmsg->cmsg_level != SOL_RXRPC)
485 			continue;
486 
487 		switch (cmsg->cmsg_type) {
488 		case RXRPC_USER_CALL_ID:
489 			if (msg->msg_flags & MSG_CMSG_COMPAT) {
490 				if (len != sizeof(u32))
491 					return -EINVAL;
492 				p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
493 			} else {
494 				if (len != sizeof(unsigned long))
495 					return -EINVAL;
496 				p->call.user_call_ID = *(unsigned long *)
497 					CMSG_DATA(cmsg);
498 			}
499 			got_user_ID = true;
500 			break;
501 
502 		case RXRPC_ABORT:
503 			if (p->command != RXRPC_CMD_SEND_DATA)
504 				return -EINVAL;
505 			p->command = RXRPC_CMD_SEND_ABORT;
506 			if (len != sizeof(p->abort_code))
507 				return -EINVAL;
508 			p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
509 			if (p->abort_code == 0)
510 				return -EINVAL;
511 			break;
512 
513 		case RXRPC_CHARGE_ACCEPT:
514 			if (p->command != RXRPC_CMD_SEND_DATA)
515 				return -EINVAL;
516 			p->command = RXRPC_CMD_CHARGE_ACCEPT;
517 			if (len != 0)
518 				return -EINVAL;
519 			break;
520 
521 		case RXRPC_EXCLUSIVE_CALL:
522 			p->exclusive = true;
523 			if (len != 0)
524 				return -EINVAL;
525 			break;
526 
527 		case RXRPC_UPGRADE_SERVICE:
528 			p->upgrade = true;
529 			if (len != 0)
530 				return -EINVAL;
531 			break;
532 
533 		case RXRPC_TX_LENGTH:
534 			if (p->call.tx_total_len != -1 || len != sizeof(__s64))
535 				return -EINVAL;
536 			p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
537 			if (p->call.tx_total_len < 0)
538 				return -EINVAL;
539 			break;
540 
541 		case RXRPC_SET_CALL_TIMEOUT:
542 			if (len & 3 || len < 4 || len > 12)
543 				return -EINVAL;
544 			memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
545 			p->call.nr_timeouts = len / 4;
546 			if (p->call.timeouts.hard > INT_MAX / HZ)
547 				return -ERANGE;
548 			if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
549 				return -ERANGE;
550 			if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
551 				return -ERANGE;
552 			break;
553 
554 		default:
555 			return -EINVAL;
556 		}
557 	}
558 
559 	if (!got_user_ID)
560 		return -EINVAL;
561 	if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
562 		return -EINVAL;
563 	_leave(" = 0");
564 	return 0;
565 }
566 
567 /*
568  * Create a new client call for sendmsg().
569  * - Called with the socket lock held, which it must release.
570  * - If it returns a call, the call's lock will need releasing by the caller.
571  */
572 static struct rxrpc_call *
573 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
574 				  struct rxrpc_send_params *p)
575 	__releases(&rx->sk.sk_lock.slock)
576 	__acquires(&call->user_mutex)
577 {
578 	struct rxrpc_conn_parameters cp;
579 	struct rxrpc_call *call;
580 	struct key *key;
581 
582 	DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
583 
584 	_enter("");
585 
586 	if (!msg->msg_name) {
587 		release_sock(&rx->sk);
588 		return ERR_PTR(-EDESTADDRREQ);
589 	}
590 
591 	key = rx->key;
592 	if (key && !rx->key->payload.data[0])
593 		key = NULL;
594 
595 	memset(&cp, 0, sizeof(cp));
596 	cp.local		= rx->local;
597 	cp.key			= rx->key;
598 	cp.security_level	= rx->min_sec_level;
599 	cp.exclusive		= rx->exclusive | p->exclusive;
600 	cp.upgrade		= p->upgrade;
601 	cp.service_id		= srx->srx_service;
602 	call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
603 				     atomic_inc_return(&rxrpc_debug_id));
604 	/* The socket is now unlocked */
605 
606 	_leave(" = %p\n", call);
607 	return call;
608 }
609 
610 /*
611  * send a message forming part of a client call through an RxRPC socket
612  * - caller holds the socket locked
613  * - the socket may be either a client socket or a server socket
614  */
615 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
616 	__releases(&rx->sk.sk_lock.slock)
617 {
618 	struct rxrpc_call *call;
619 	unsigned long now, j;
620 	bool dropped_lock = false;
621 	int ret;
622 
623 	struct rxrpc_send_params p = {
624 		.call.tx_total_len	= -1,
625 		.call.user_call_ID	= 0,
626 		.call.nr_timeouts	= 0,
627 		.call.interruptibility	= RXRPC_INTERRUPTIBLE,
628 		.abort_code		= 0,
629 		.command		= RXRPC_CMD_SEND_DATA,
630 		.exclusive		= false,
631 		.upgrade		= false,
632 	};
633 
634 	_enter("");
635 
636 	ret = rxrpc_sendmsg_cmsg(msg, &p);
637 	if (ret < 0)
638 		goto error_release_sock;
639 
640 	if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
641 		ret = -EINVAL;
642 		if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
643 			goto error_release_sock;
644 		ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
645 		goto error_release_sock;
646 	}
647 
648 	call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
649 	if (!call) {
650 		ret = -EBADSLT;
651 		if (p.command != RXRPC_CMD_SEND_DATA)
652 			goto error_release_sock;
653 		call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
654 		/* The socket is now unlocked... */
655 		if (IS_ERR(call))
656 			return PTR_ERR(call);
657 		/* ... and we have the call lock. */
658 		ret = 0;
659 		if (rxrpc_call_is_complete(call))
660 			goto out_put_unlock;
661 	} else {
662 		switch (rxrpc_call_state(call)) {
663 		case RXRPC_CALL_UNINITIALISED:
664 		case RXRPC_CALL_CLIENT_AWAIT_CONN:
665 		case RXRPC_CALL_SERVER_PREALLOC:
666 		case RXRPC_CALL_SERVER_SECURING:
667 			rxrpc_put_call(call, rxrpc_call_put_sendmsg);
668 			ret = -EBUSY;
669 			goto error_release_sock;
670 		default:
671 			break;
672 		}
673 
674 		ret = mutex_lock_interruptible(&call->user_mutex);
675 		release_sock(&rx->sk);
676 		if (ret < 0) {
677 			ret = -ERESTARTSYS;
678 			goto error_put;
679 		}
680 
681 		if (p.call.tx_total_len != -1) {
682 			ret = -EINVAL;
683 			if (call->tx_total_len != -1 ||
684 			    call->tx_pending ||
685 			    call->tx_top != 0)
686 				goto out_put_unlock;
687 			call->tx_total_len = p.call.tx_total_len;
688 		}
689 	}
690 
691 	switch (p.call.nr_timeouts) {
692 	case 3:
693 		j = msecs_to_jiffies(p.call.timeouts.normal);
694 		if (p.call.timeouts.normal > 0 && j == 0)
695 			j = 1;
696 		WRITE_ONCE(call->next_rx_timo, j);
697 		fallthrough;
698 	case 2:
699 		j = msecs_to_jiffies(p.call.timeouts.idle);
700 		if (p.call.timeouts.idle > 0 && j == 0)
701 			j = 1;
702 		WRITE_ONCE(call->next_req_timo, j);
703 		fallthrough;
704 	case 1:
705 		if (p.call.timeouts.hard > 0) {
706 			j = msecs_to_jiffies(p.call.timeouts.hard);
707 			now = jiffies;
708 			j += now;
709 			WRITE_ONCE(call->expect_term_by, j);
710 			rxrpc_reduce_call_timer(call, j, now,
711 						rxrpc_timer_set_for_hard);
712 		}
713 		break;
714 	}
715 
716 	if (rxrpc_call_is_complete(call)) {
717 		/* it's too late for this call */
718 		ret = -ESHUTDOWN;
719 	} else if (p.command == RXRPC_CMD_SEND_ABORT) {
720 		rxrpc_propose_abort(call, p.abort_code, -ECONNABORTED,
721 				    rxrpc_abort_call_sendmsg);
722 		ret = 0;
723 	} else if (p.command != RXRPC_CMD_SEND_DATA) {
724 		ret = -EINVAL;
725 	} else {
726 		ret = rxrpc_send_data(rx, call, msg, len, NULL, &dropped_lock);
727 	}
728 
729 out_put_unlock:
730 	if (!dropped_lock)
731 		mutex_unlock(&call->user_mutex);
732 error_put:
733 	rxrpc_put_call(call, rxrpc_call_put_sendmsg);
734 	_leave(" = %d", ret);
735 	return ret;
736 
737 error_release_sock:
738 	release_sock(&rx->sk);
739 	return ret;
740 }
741 
742 /**
743  * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
744  * @sock: The socket the call is on
745  * @call: The call to send data through
746  * @msg: The data to send
747  * @len: The amount of data to send
748  * @notify_end_tx: Notification that the last packet is queued.
749  *
750  * Allow a kernel service to send data on a call.  The call must be in an state
751  * appropriate to sending data.  No control data should be supplied in @msg,
752  * nor should an address be supplied.  MSG_MORE should be flagged if there's
753  * more data to come, otherwise this data will end the transmission phase.
754  */
755 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
756 			   struct msghdr *msg, size_t len,
757 			   rxrpc_notify_end_tx_t notify_end_tx)
758 {
759 	bool dropped_lock = false;
760 	int ret;
761 
762 	_enter("{%d},", call->debug_id);
763 
764 	ASSERTCMP(msg->msg_name, ==, NULL);
765 	ASSERTCMP(msg->msg_control, ==, NULL);
766 
767 	mutex_lock(&call->user_mutex);
768 
769 	ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
770 			      notify_end_tx, &dropped_lock);
771 	if (ret == -ESHUTDOWN)
772 		ret = call->error;
773 
774 	if (!dropped_lock)
775 		mutex_unlock(&call->user_mutex);
776 	_leave(" = %d", ret);
777 	return ret;
778 }
779 EXPORT_SYMBOL(rxrpc_kernel_send_data);
780 
781 /**
782  * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
783  * @sock: The socket the call is on
784  * @call: The call to be aborted
785  * @abort_code: The abort code to stick into the ABORT packet
786  * @error: Local error value
787  * @why: Indication as to why.
788  *
789  * Allow a kernel service to abort a call, if it's still in an abortable state
790  * and return true if the call was aborted, false if it was already complete.
791  */
792 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
793 			     u32 abort_code, int error, enum rxrpc_abort_reason why)
794 {
795 	bool aborted;
796 
797 	_enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
798 
799 	mutex_lock(&call->user_mutex);
800 	aborted = rxrpc_propose_abort(call, abort_code, error, why);
801 	mutex_unlock(&call->user_mutex);
802 	return aborted;
803 }
804 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
805 
806 /**
807  * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
808  * @sock: The socket the call is on
809  * @call: The call to be informed
810  * @tx_total_len: The amount of data to be transmitted for this call
811  *
812  * Allow a kernel service to set the total transmit length on a call.  This
813  * allows buffer-to-packet encrypt-and-copy to be performed.
814  *
815  * This function is primarily for use for setting the reply length since the
816  * request length can be set when beginning the call.
817  */
818 void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
819 				s64 tx_total_len)
820 {
821 	WARN_ON(call->tx_total_len != -1);
822 	call->tx_total_len = tx_total_len;
823 }
824 EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);
825