xref: /linux/net/rxrpc/sendmsg.c (revision 9a379e77033f02c4a071891afdf0f0a01eff8ccb)
1 /* AF_RXRPC sendmsg() implementation.
2  *
3  * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public Licence
8  * as published by the Free Software Foundation; either version
9  * 2 of the Licence, or (at your option) any later version.
10  */
11 
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13 
14 #include <linux/net.h>
15 #include <linux/gfp.h>
16 #include <linux/skbuff.h>
17 #include <linux/export.h>
18 #include <linux/sched/signal.h>
19 
20 #include <net/sock.h>
21 #include <net/af_rxrpc.h>
22 #include "ar-internal.h"
23 
24 /*
25  * Wait for space to appear in the Tx queue or a signal to occur.
26  */
27 static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
28 					 struct rxrpc_call *call,
29 					 long *timeo)
30 {
31 	for (;;) {
32 		set_current_state(TASK_INTERRUPTIBLE);
33 		if (call->tx_top - call->tx_hard_ack <
34 		    min_t(unsigned int, call->tx_winsize,
35 			  call->cong_cwnd + call->cong_extra))
36 			return 0;
37 
38 		if (call->state >= RXRPC_CALL_COMPLETE)
39 			return call->error;
40 
41 		if (signal_pending(current))
42 			return sock_intr_errno(*timeo);
43 
44 		trace_rxrpc_transmit(call, rxrpc_transmit_wait);
45 		mutex_unlock(&call->user_mutex);
46 		*timeo = schedule_timeout(*timeo);
47 		if (mutex_lock_interruptible(&call->user_mutex) < 0)
48 			return sock_intr_errno(*timeo);
49 	}
50 }
51 
52 /*
53  * Wait for space to appear in the Tx queue uninterruptibly, but with
54  * a timeout of 2*RTT if no progress was made and a signal occurred.
55  */
56 static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
57 					    struct rxrpc_call *call)
58 {
59 	rxrpc_seq_t tx_start, tx_win;
60 	signed long rtt2, timeout;
61 	u64 rtt;
62 
63 	rtt = READ_ONCE(call->peer->rtt);
64 	rtt2 = nsecs_to_jiffies64(rtt) * 2;
65 	if (rtt2 < 1)
66 		rtt2 = 1;
67 
68 	timeout = rtt2;
69 	tx_start = READ_ONCE(call->tx_hard_ack);
70 
71 	for (;;) {
72 		set_current_state(TASK_UNINTERRUPTIBLE);
73 
74 		tx_win = READ_ONCE(call->tx_hard_ack);
75 		if (call->tx_top - tx_win <
76 		    min_t(unsigned int, call->tx_winsize,
77 			  call->cong_cwnd + call->cong_extra))
78 			return 0;
79 
80 		if (call->state >= RXRPC_CALL_COMPLETE)
81 			return call->error;
82 
83 		if (timeout == 0 &&
84 		    tx_win == tx_start && signal_pending(current))
85 			return -EINTR;
86 
87 		if (tx_win != tx_start) {
88 			timeout = rtt2;
89 			tx_start = tx_win;
90 		}
91 
92 		trace_rxrpc_transmit(call, rxrpc_transmit_wait);
93 		timeout = schedule_timeout(timeout);
94 	}
95 }
96 
97 /*
98  * wait for space to appear in the transmit/ACK window
99  * - caller holds the socket locked
100  */
101 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
102 				    struct rxrpc_call *call,
103 				    long *timeo,
104 				    bool waitall)
105 {
106 	DECLARE_WAITQUEUE(myself, current);
107 	int ret;
108 
109 	_enter(",{%u,%u,%u}",
110 	       call->tx_hard_ack, call->tx_top, call->tx_winsize);
111 
112 	add_wait_queue(&call->waitq, &myself);
113 
114 	if (waitall)
115 		ret = rxrpc_wait_for_tx_window_nonintr(rx, call);
116 	else
117 		ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
118 
119 	remove_wait_queue(&call->waitq, &myself);
120 	set_current_state(TASK_RUNNING);
121 	_leave(" = %d", ret);
122 	return ret;
123 }
124 
125 /*
126  * Schedule an instant Tx resend.
127  */
128 static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
129 {
130 	spin_lock_bh(&call->lock);
131 
132 	if (call->state < RXRPC_CALL_COMPLETE) {
133 		call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS;
134 		if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
135 			rxrpc_queue_call(call);
136 	}
137 
138 	spin_unlock_bh(&call->lock);
139 }
140 
141 /*
142  * Notify the owner of the call that the transmit phase is ended and the last
143  * packet has been queued.
144  */
145 static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
146 				rxrpc_notify_end_tx_t notify_end_tx)
147 {
148 	if (notify_end_tx)
149 		notify_end_tx(&rx->sk, call, call->user_call_ID);
150 }
151 
152 /*
153  * Queue a DATA packet for transmission, set the resend timeout and send the
154  * packet immediately
155  */
156 static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
157 			       struct sk_buff *skb, bool last,
158 			       rxrpc_notify_end_tx_t notify_end_tx)
159 {
160 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
161 	unsigned long now;
162 	rxrpc_seq_t seq = sp->hdr.seq;
163 	int ret, ix;
164 	u8 annotation = RXRPC_TX_ANNO_UNACK;
165 
166 	_net("queue skb %p [%d]", skb, seq);
167 
168 	ASSERTCMP(seq, ==, call->tx_top + 1);
169 
170 	if (last) {
171 		annotation |= RXRPC_TX_ANNO_LAST;
172 		set_bit(RXRPC_CALL_TX_LASTQ, &call->flags);
173 	}
174 
175 	/* We have to set the timestamp before queueing as the retransmit
176 	 * algorithm can see the packet as soon as we queue it.
177 	 */
178 	skb->tstamp = ktime_get_real();
179 
180 	ix = seq & RXRPC_RXTX_BUFF_MASK;
181 	rxrpc_get_skb(skb, rxrpc_skb_tx_got);
182 	call->rxtx_annotations[ix] = annotation;
183 	smp_wmb();
184 	call->rxtx_buffer[ix] = skb;
185 	call->tx_top = seq;
186 	if (last)
187 		trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
188 	else
189 		trace_rxrpc_transmit(call, rxrpc_transmit_queue);
190 
191 	if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
192 		_debug("________awaiting reply/ACK__________");
193 		write_lock_bh(&call->state_lock);
194 		switch (call->state) {
195 		case RXRPC_CALL_CLIENT_SEND_REQUEST:
196 			call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
197 			rxrpc_notify_end_tx(rx, call, notify_end_tx);
198 			break;
199 		case RXRPC_CALL_SERVER_ACK_REQUEST:
200 			call->state = RXRPC_CALL_SERVER_SEND_REPLY;
201 			now = jiffies;
202 			WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
203 			if (call->ackr_reason == RXRPC_ACK_DELAY)
204 				call->ackr_reason = 0;
205 			trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
206 			if (!last)
207 				break;
208 			/* Fall through */
209 		case RXRPC_CALL_SERVER_SEND_REPLY:
210 			call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
211 			rxrpc_notify_end_tx(rx, call, notify_end_tx);
212 			break;
213 		default:
214 			break;
215 		}
216 		write_unlock_bh(&call->state_lock);
217 	}
218 
219 	if (seq == 1 && rxrpc_is_client_call(call))
220 		rxrpc_expose_client_call(call);
221 
222 	ret = rxrpc_send_data_packet(call, skb, false);
223 	if (ret < 0) {
224 		_debug("need instant resend %d", ret);
225 		rxrpc_instant_resend(call, ix);
226 	} else {
227 		unsigned long now = jiffies, resend_at;
228 
229 		if (call->peer->rtt_usage > 1)
230 			resend_at = nsecs_to_jiffies(call->peer->rtt * 3 / 2);
231 		else
232 			resend_at = rxrpc_resend_timeout;
233 		if (resend_at < 1)
234 			resend_at = 1;
235 
236 		resend_at += now;
237 		WRITE_ONCE(call->resend_at, resend_at);
238 		rxrpc_reduce_call_timer(call, resend_at, now,
239 					rxrpc_timer_set_for_send);
240 	}
241 
242 	rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
243 	_leave("");
244 }
245 
246 /*
247  * send data through a socket
248  * - must be called in process context
249  * - The caller holds the call user access mutex, but not the socket lock.
250  */
251 static int rxrpc_send_data(struct rxrpc_sock *rx,
252 			   struct rxrpc_call *call,
253 			   struct msghdr *msg, size_t len,
254 			   rxrpc_notify_end_tx_t notify_end_tx)
255 {
256 	struct rxrpc_skb_priv *sp;
257 	struct sk_buff *skb;
258 	struct sock *sk = &rx->sk;
259 	long timeo;
260 	bool more;
261 	int ret, copied;
262 
263 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
264 
265 	/* this should be in poll */
266 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
267 
268 	if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
269 		return -EPIPE;
270 
271 	more = msg->msg_flags & MSG_MORE;
272 
273 	if (call->tx_total_len != -1) {
274 		if (len > call->tx_total_len)
275 			return -EMSGSIZE;
276 		if (!more && len != call->tx_total_len)
277 			return -EMSGSIZE;
278 	}
279 
280 	skb = call->tx_pending;
281 	call->tx_pending = NULL;
282 	rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
283 
284 	copied = 0;
285 	do {
286 		/* Check to see if there's a ping ACK to reply to. */
287 		if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
288 			rxrpc_send_ack_packet(call, false, NULL);
289 
290 		if (!skb) {
291 			size_t size, chunk, max, space;
292 
293 			_debug("alloc");
294 
295 			if (call->tx_top - call->tx_hard_ack >=
296 			    min_t(unsigned int, call->tx_winsize,
297 				  call->cong_cwnd + call->cong_extra)) {
298 				ret = -EAGAIN;
299 				if (msg->msg_flags & MSG_DONTWAIT)
300 					goto maybe_error;
301 				ret = rxrpc_wait_for_tx_window(rx, call,
302 							       &timeo,
303 							       msg->msg_flags & MSG_WAITALL);
304 				if (ret < 0)
305 					goto maybe_error;
306 			}
307 
308 			max = RXRPC_JUMBO_DATALEN;
309 			max -= call->conn->security_size;
310 			max &= ~(call->conn->size_align - 1UL);
311 
312 			chunk = max;
313 			if (chunk > msg_data_left(msg) && !more)
314 				chunk = msg_data_left(msg);
315 
316 			space = chunk + call->conn->size_align;
317 			space &= ~(call->conn->size_align - 1UL);
318 
319 			size = space + call->conn->security_size;
320 
321 			_debug("SIZE: %zu/%zu/%zu", chunk, space, size);
322 
323 			/* create a buffer that we can retain until it's ACK'd */
324 			skb = sock_alloc_send_skb(
325 				sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
326 			if (!skb)
327 				goto maybe_error;
328 
329 			rxrpc_new_skb(skb, rxrpc_skb_tx_new);
330 
331 			_debug("ALLOC SEND %p", skb);
332 
333 			ASSERTCMP(skb->mark, ==, 0);
334 
335 			_debug("HS: %u", call->conn->security_size);
336 			skb_reserve(skb, call->conn->security_size);
337 			skb->len += call->conn->security_size;
338 
339 			sp = rxrpc_skb(skb);
340 			sp->remain = chunk;
341 			if (sp->remain > skb_tailroom(skb))
342 				sp->remain = skb_tailroom(skb);
343 
344 			_net("skb: hr %d, tr %d, hl %d, rm %d",
345 			       skb_headroom(skb),
346 			       skb_tailroom(skb),
347 			       skb_headlen(skb),
348 			       sp->remain);
349 
350 			skb->ip_summed = CHECKSUM_UNNECESSARY;
351 		}
352 
353 		_debug("append");
354 		sp = rxrpc_skb(skb);
355 
356 		/* append next segment of data to the current buffer */
357 		if (msg_data_left(msg) > 0) {
358 			int copy = skb_tailroom(skb);
359 			ASSERTCMP(copy, >, 0);
360 			if (copy > msg_data_left(msg))
361 				copy = msg_data_left(msg);
362 			if (copy > sp->remain)
363 				copy = sp->remain;
364 
365 			_debug("add");
366 			ret = skb_add_data(skb, &msg->msg_iter, copy);
367 			_debug("added");
368 			if (ret < 0)
369 				goto efault;
370 			sp->remain -= copy;
371 			skb->mark += copy;
372 			copied += copy;
373 			if (call->tx_total_len != -1)
374 				call->tx_total_len -= copy;
375 		}
376 
377 		/* add the packet to the send queue if it's now full */
378 		if (sp->remain <= 0 ||
379 		    (msg_data_left(msg) == 0 && !more)) {
380 			struct rxrpc_connection *conn = call->conn;
381 			uint32_t seq;
382 			size_t pad;
383 
384 			/* pad out if we're using security */
385 			if (conn->security_ix) {
386 				pad = conn->security_size + skb->mark;
387 				pad = conn->size_align - pad;
388 				pad &= conn->size_align - 1;
389 				_debug("pad %zu", pad);
390 				if (pad)
391 					skb_put_zero(skb, pad);
392 			}
393 
394 			seq = call->tx_top + 1;
395 
396 			sp->hdr.seq	= seq;
397 			sp->hdr._rsvd	= 0;
398 			sp->hdr.flags	= conn->out_clientflag;
399 
400 			if (msg_data_left(msg) == 0 && !more)
401 				sp->hdr.flags |= RXRPC_LAST_PACKET;
402 			else if (call->tx_top - call->tx_hard_ack <
403 				 call->tx_winsize)
404 				sp->hdr.flags |= RXRPC_MORE_PACKETS;
405 
406 			ret = conn->security->secure_packet(
407 				call, skb, skb->mark, skb->head);
408 			if (ret < 0)
409 				goto out;
410 
411 			rxrpc_queue_packet(rx, call, skb,
412 					   !msg_data_left(msg) && !more,
413 					   notify_end_tx);
414 			skb = NULL;
415 		}
416 
417 		/* Check for the far side aborting the call or a network error
418 		 * occurring.  If this happens, save any packet that was under
419 		 * construction so that in the case of a network error, the
420 		 * call can be retried or redirected.
421 		 */
422 		if (call->state == RXRPC_CALL_COMPLETE) {
423 			ret = call->error;
424 			goto out;
425 		}
426 	} while (msg_data_left(msg) > 0);
427 
428 success:
429 	ret = copied;
430 out:
431 	call->tx_pending = skb;
432 	_leave(" = %d", ret);
433 	return ret;
434 
435 maybe_error:
436 	if (copied)
437 		goto success;
438 	goto out;
439 
440 efault:
441 	ret = -EFAULT;
442 	goto out;
443 }
444 
445 /*
446  * extract control messages from the sendmsg() control buffer
447  */
448 static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
449 {
450 	struct cmsghdr *cmsg;
451 	bool got_user_ID = false;
452 	int len;
453 
454 	if (msg->msg_controllen == 0)
455 		return -EINVAL;
456 
457 	for_each_cmsghdr(cmsg, msg) {
458 		if (!CMSG_OK(msg, cmsg))
459 			return -EINVAL;
460 
461 		len = cmsg->cmsg_len - sizeof(struct cmsghdr);
462 		_debug("CMSG %d, %d, %d",
463 		       cmsg->cmsg_level, cmsg->cmsg_type, len);
464 
465 		if (cmsg->cmsg_level != SOL_RXRPC)
466 			continue;
467 
468 		switch (cmsg->cmsg_type) {
469 		case RXRPC_USER_CALL_ID:
470 			if (msg->msg_flags & MSG_CMSG_COMPAT) {
471 				if (len != sizeof(u32))
472 					return -EINVAL;
473 				p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
474 			} else {
475 				if (len != sizeof(unsigned long))
476 					return -EINVAL;
477 				p->call.user_call_ID = *(unsigned long *)
478 					CMSG_DATA(cmsg);
479 			}
480 			got_user_ID = true;
481 			break;
482 
483 		case RXRPC_ABORT:
484 			if (p->command != RXRPC_CMD_SEND_DATA)
485 				return -EINVAL;
486 			p->command = RXRPC_CMD_SEND_ABORT;
487 			if (len != sizeof(p->abort_code))
488 				return -EINVAL;
489 			p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
490 			if (p->abort_code == 0)
491 				return -EINVAL;
492 			break;
493 
494 		case RXRPC_ACCEPT:
495 			if (p->command != RXRPC_CMD_SEND_DATA)
496 				return -EINVAL;
497 			p->command = RXRPC_CMD_ACCEPT;
498 			if (len != 0)
499 				return -EINVAL;
500 			break;
501 
502 		case RXRPC_EXCLUSIVE_CALL:
503 			p->exclusive = true;
504 			if (len != 0)
505 				return -EINVAL;
506 			break;
507 
508 		case RXRPC_UPGRADE_SERVICE:
509 			p->upgrade = true;
510 			if (len != 0)
511 				return -EINVAL;
512 			break;
513 
514 		case RXRPC_TX_LENGTH:
515 			if (p->call.tx_total_len != -1 || len != sizeof(__s64))
516 				return -EINVAL;
517 			p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
518 			if (p->call.tx_total_len < 0)
519 				return -EINVAL;
520 			break;
521 
522 		case RXRPC_SET_CALL_TIMEOUT:
523 			if (len & 3 || len < 4 || len > 12)
524 				return -EINVAL;
525 			memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
526 			p->call.nr_timeouts = len / 4;
527 			if (p->call.timeouts.hard > INT_MAX / HZ)
528 				return -ERANGE;
529 			if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
530 				return -ERANGE;
531 			if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
532 				return -ERANGE;
533 			break;
534 
535 		default:
536 			return -EINVAL;
537 		}
538 	}
539 
540 	if (!got_user_ID)
541 		return -EINVAL;
542 	if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
543 		return -EINVAL;
544 	_leave(" = 0");
545 	return 0;
546 }
547 
548 /*
549  * Create a new client call for sendmsg().
550  * - Called with the socket lock held, which it must release.
551  * - If it returns a call, the call's lock will need releasing by the caller.
552  */
553 static struct rxrpc_call *
554 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
555 				  struct rxrpc_send_params *p)
556 	__releases(&rx->sk.sk_lock.slock)
557 {
558 	struct rxrpc_conn_parameters cp;
559 	struct rxrpc_call *call;
560 	struct key *key;
561 
562 	DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
563 
564 	_enter("");
565 
566 	if (!msg->msg_name) {
567 		release_sock(&rx->sk);
568 		return ERR_PTR(-EDESTADDRREQ);
569 	}
570 
571 	key = rx->key;
572 	if (key && !rx->key->payload.data[0])
573 		key = NULL;
574 
575 	memset(&cp, 0, sizeof(cp));
576 	cp.local		= rx->local;
577 	cp.key			= rx->key;
578 	cp.security_level	= rx->min_sec_level;
579 	cp.exclusive		= rx->exclusive | p->exclusive;
580 	cp.upgrade		= p->upgrade;
581 	cp.service_id		= srx->srx_service;
582 	call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL);
583 	/* The socket is now unlocked */
584 
585 	_leave(" = %p\n", call);
586 	return call;
587 }
588 
589 /*
590  * send a message forming part of a client call through an RxRPC socket
591  * - caller holds the socket locked
592  * - the socket may be either a client socket or a server socket
593  */
594 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
595 	__releases(&rx->sk.sk_lock.slock)
596 {
597 	enum rxrpc_call_state state;
598 	struct rxrpc_call *call;
599 	unsigned long now, j;
600 	int ret;
601 
602 	struct rxrpc_send_params p = {
603 		.call.tx_total_len	= -1,
604 		.call.user_call_ID	= 0,
605 		.call.nr_timeouts	= 0,
606 		.abort_code		= 0,
607 		.command		= RXRPC_CMD_SEND_DATA,
608 		.exclusive		= false,
609 		.upgrade		= false,
610 	};
611 
612 	_enter("");
613 
614 	ret = rxrpc_sendmsg_cmsg(msg, &p);
615 	if (ret < 0)
616 		goto error_release_sock;
617 
618 	if (p.command == RXRPC_CMD_ACCEPT) {
619 		ret = -EINVAL;
620 		if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
621 			goto error_release_sock;
622 		call = rxrpc_accept_call(rx, p.call.user_call_ID, NULL);
623 		/* The socket is now unlocked. */
624 		if (IS_ERR(call))
625 			return PTR_ERR(call);
626 		ret = 0;
627 		goto out_put_unlock;
628 	}
629 
630 	call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
631 	if (!call) {
632 		ret = -EBADSLT;
633 		if (p.command != RXRPC_CMD_SEND_DATA)
634 			goto error_release_sock;
635 		call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
636 		/* The socket is now unlocked... */
637 		if (IS_ERR(call))
638 			return PTR_ERR(call);
639 		/* ... and we have the call lock. */
640 	} else {
641 		switch (READ_ONCE(call->state)) {
642 		case RXRPC_CALL_UNINITIALISED:
643 		case RXRPC_CALL_CLIENT_AWAIT_CONN:
644 		case RXRPC_CALL_SERVER_PREALLOC:
645 		case RXRPC_CALL_SERVER_SECURING:
646 		case RXRPC_CALL_SERVER_ACCEPTING:
647 			ret = -EBUSY;
648 			goto error_release_sock;
649 		default:
650 			break;
651 		}
652 
653 		ret = mutex_lock_interruptible(&call->user_mutex);
654 		release_sock(&rx->sk);
655 		if (ret < 0) {
656 			ret = -ERESTARTSYS;
657 			goto error_put;
658 		}
659 
660 		if (p.call.tx_total_len != -1) {
661 			ret = -EINVAL;
662 			if (call->tx_total_len != -1 ||
663 			    call->tx_pending ||
664 			    call->tx_top != 0)
665 				goto error_put;
666 			call->tx_total_len = p.call.tx_total_len;
667 		}
668 	}
669 
670 	switch (p.call.nr_timeouts) {
671 	case 3:
672 		j = msecs_to_jiffies(p.call.timeouts.normal);
673 		if (p.call.timeouts.normal > 0 && j == 0)
674 			j = 1;
675 		WRITE_ONCE(call->next_rx_timo, j);
676 		/* Fall through */
677 	case 2:
678 		j = msecs_to_jiffies(p.call.timeouts.idle);
679 		if (p.call.timeouts.idle > 0 && j == 0)
680 			j = 1;
681 		WRITE_ONCE(call->next_req_timo, j);
682 		/* Fall through */
683 	case 1:
684 		if (p.call.timeouts.hard > 0) {
685 			j = msecs_to_jiffies(p.call.timeouts.hard);
686 			now = jiffies;
687 			j += now;
688 			WRITE_ONCE(call->expect_term_by, j);
689 			rxrpc_reduce_call_timer(call, j, now,
690 						rxrpc_timer_set_for_hard);
691 		}
692 		break;
693 	}
694 
695 	state = READ_ONCE(call->state);
696 	_debug("CALL %d USR %lx ST %d on CONN %p",
697 	       call->debug_id, call->user_call_ID, state, call->conn);
698 
699 	if (state >= RXRPC_CALL_COMPLETE) {
700 		/* it's too late for this call */
701 		ret = -ESHUTDOWN;
702 	} else if (p.command == RXRPC_CMD_SEND_ABORT) {
703 		ret = 0;
704 		if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
705 			ret = rxrpc_send_abort_packet(call);
706 	} else if (p.command != RXRPC_CMD_SEND_DATA) {
707 		ret = -EINVAL;
708 	} else if (rxrpc_is_client_call(call) &&
709 		   state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
710 		/* request phase complete for this client call */
711 		ret = -EPROTO;
712 	} else if (rxrpc_is_service_call(call) &&
713 		   state != RXRPC_CALL_SERVER_ACK_REQUEST &&
714 		   state != RXRPC_CALL_SERVER_SEND_REPLY) {
715 		/* Reply phase not begun or not complete for service call. */
716 		ret = -EPROTO;
717 	} else {
718 		ret = rxrpc_send_data(rx, call, msg, len, NULL);
719 	}
720 
721 out_put_unlock:
722 	mutex_unlock(&call->user_mutex);
723 error_put:
724 	rxrpc_put_call(call, rxrpc_call_put);
725 	_leave(" = %d", ret);
726 	return ret;
727 
728 error_release_sock:
729 	release_sock(&rx->sk);
730 	return ret;
731 }
732 
733 /**
734  * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
735  * @sock: The socket the call is on
736  * @call: The call to send data through
737  * @msg: The data to send
738  * @len: The amount of data to send
739  * @notify_end_tx: Notification that the last packet is queued.
740  *
741  * Allow a kernel service to send data on a call.  The call must be in an state
742  * appropriate to sending data.  No control data should be supplied in @msg,
743  * nor should an address be supplied.  MSG_MORE should be flagged if there's
744  * more data to come, otherwise this data will end the transmission phase.
745  */
746 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
747 			   struct msghdr *msg, size_t len,
748 			   rxrpc_notify_end_tx_t notify_end_tx)
749 {
750 	int ret;
751 
752 	_enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
753 
754 	ASSERTCMP(msg->msg_name, ==, NULL);
755 	ASSERTCMP(msg->msg_control, ==, NULL);
756 
757 	mutex_lock(&call->user_mutex);
758 
759 	_debug("CALL %d USR %lx ST %d on CONN %p",
760 	       call->debug_id, call->user_call_ID, call->state, call->conn);
761 
762 	switch (READ_ONCE(call->state)) {
763 	case RXRPC_CALL_CLIENT_SEND_REQUEST:
764 	case RXRPC_CALL_SERVER_ACK_REQUEST:
765 	case RXRPC_CALL_SERVER_SEND_REPLY:
766 		ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
767 				      notify_end_tx);
768 		break;
769 	case RXRPC_CALL_COMPLETE:
770 		read_lock_bh(&call->state_lock);
771 		ret = call->error;
772 		read_unlock_bh(&call->state_lock);
773 		break;
774 	default:
775 		/* Request phase complete for this client call */
776 		trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
777 		ret = -EPROTO;
778 		break;
779 	}
780 
781 	mutex_unlock(&call->user_mutex);
782 	_leave(" = %d", ret);
783 	return ret;
784 }
785 EXPORT_SYMBOL(rxrpc_kernel_send_data);
786 
787 /**
788  * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
789  * @sock: The socket the call is on
790  * @call: The call to be aborted
791  * @abort_code: The abort code to stick into the ABORT packet
792  * @error: Local error value
793  * @why: 3-char string indicating why.
794  *
795  * Allow a kernel service to abort a call, if it's still in an abortable state
796  * and return true if the call was aborted, false if it was already complete.
797  */
798 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
799 			     u32 abort_code, int error, const char *why)
800 {
801 	bool aborted;
802 
803 	_enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
804 
805 	mutex_lock(&call->user_mutex);
806 
807 	aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
808 	if (aborted)
809 		rxrpc_send_abort_packet(call);
810 
811 	mutex_unlock(&call->user_mutex);
812 	return aborted;
813 }
814 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
815 
816 /**
817  * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
818  * @sock: The socket the call is on
819  * @call: The call to be informed
820  * @tx_total_len: The amount of data to be transmitted for this call
821  *
822  * Allow a kernel service to set the total transmit length on a call.  This
823  * allows buffer-to-packet encrypt-and-copy to be performed.
824  *
825  * This function is primarily for use for setting the reply length since the
826  * request length can be set when beginning the call.
827  */
828 void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
829 				s64 tx_total_len)
830 {
831 	WARN_ON(call->tx_total_len != -1);
832 	call->tx_total_len = tx_total_len;
833 }
834 EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);
835