xref: /openbmc/linux/net/rxrpc/sendmsg.c (revision e553d2a5)
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  * Wait for space to appear in the Tx queue or a signal to occur.
22  */
23 static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
24 					 struct rxrpc_call *call,
25 					 long *timeo)
26 {
27 	for (;;) {
28 		set_current_state(TASK_INTERRUPTIBLE);
29 		if (call->tx_top - call->tx_hard_ack <
30 		    min_t(unsigned int, call->tx_winsize,
31 			  call->cong_cwnd + call->cong_extra))
32 			return 0;
33 
34 		if (call->state >= RXRPC_CALL_COMPLETE)
35 			return call->error;
36 
37 		if (signal_pending(current))
38 			return sock_intr_errno(*timeo);
39 
40 		trace_rxrpc_transmit(call, rxrpc_transmit_wait);
41 		mutex_unlock(&call->user_mutex);
42 		*timeo = schedule_timeout(*timeo);
43 		if (mutex_lock_interruptible(&call->user_mutex) < 0)
44 			return sock_intr_errno(*timeo);
45 	}
46 }
47 
48 /*
49  * Wait for space to appear in the Tx queue uninterruptibly, but with
50  * a timeout of 2*RTT if no progress was made and a signal occurred.
51  */
52 static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
53 					    struct rxrpc_call *call)
54 {
55 	rxrpc_seq_t tx_start, tx_win;
56 	signed long rtt2, timeout;
57 	u64 rtt;
58 
59 	rtt = READ_ONCE(call->peer->rtt);
60 	rtt2 = nsecs_to_jiffies64(rtt) * 2;
61 	if (rtt2 < 1)
62 		rtt2 = 1;
63 
64 	timeout = rtt2;
65 	tx_start = READ_ONCE(call->tx_hard_ack);
66 
67 	for (;;) {
68 		set_current_state(TASK_UNINTERRUPTIBLE);
69 
70 		tx_win = READ_ONCE(call->tx_hard_ack);
71 		if (call->tx_top - tx_win <
72 		    min_t(unsigned int, call->tx_winsize,
73 			  call->cong_cwnd + call->cong_extra))
74 			return 0;
75 
76 		if (call->state >= RXRPC_CALL_COMPLETE)
77 			return call->error;
78 
79 		if (test_bit(RXRPC_CALL_IS_INTR, &call->flags) &&
80 		    timeout == 0 &&
81 		    tx_win == tx_start && signal_pending(current))
82 			return -EINTR;
83 
84 		if (tx_win != tx_start) {
85 			timeout = rtt2;
86 			tx_start = tx_win;
87 		}
88 
89 		trace_rxrpc_transmit(call, rxrpc_transmit_wait);
90 		timeout = schedule_timeout(timeout);
91 	}
92 }
93 
94 /*
95  * wait for space to appear in the transmit/ACK window
96  * - caller holds the socket locked
97  */
98 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
99 				    struct rxrpc_call *call,
100 				    long *timeo,
101 				    bool waitall)
102 {
103 	DECLARE_WAITQUEUE(myself, current);
104 	int ret;
105 
106 	_enter(",{%u,%u,%u}",
107 	       call->tx_hard_ack, call->tx_top, call->tx_winsize);
108 
109 	add_wait_queue(&call->waitq, &myself);
110 
111 	if (waitall)
112 		ret = rxrpc_wait_for_tx_window_nonintr(rx, call);
113 	else
114 		ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
115 
116 	remove_wait_queue(&call->waitq, &myself);
117 	set_current_state(TASK_RUNNING);
118 	_leave(" = %d", ret);
119 	return ret;
120 }
121 
122 /*
123  * Schedule an instant Tx resend.
124  */
125 static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
126 {
127 	spin_lock_bh(&call->lock);
128 
129 	if (call->state < RXRPC_CALL_COMPLETE) {
130 		call->rxtx_annotations[ix] =
131 			(call->rxtx_annotations[ix] & RXRPC_TX_ANNO_LAST) |
132 			RXRPC_TX_ANNO_RETRANS;
133 		if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
134 			rxrpc_queue_call(call);
135 	}
136 
137 	spin_unlock_bh(&call->lock);
138 }
139 
140 /*
141  * Notify the owner of the call that the transmit phase is ended and the last
142  * packet has been queued.
143  */
144 static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
145 				rxrpc_notify_end_tx_t notify_end_tx)
146 {
147 	if (notify_end_tx)
148 		notify_end_tx(&rx->sk, call, call->user_call_ID);
149 }
150 
151 /*
152  * Queue a DATA packet for transmission, set the resend timeout and send
153  * the packet immediately.  Returns the error from rxrpc_send_data_packet()
154  * in case the caller wants to do something with it.
155  */
156 static int 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 
173 	/* We have to set the timestamp before queueing as the retransmit
174 	 * algorithm can see the packet as soon as we queue it.
175 	 */
176 	skb->tstamp = ktime_get_real();
177 
178 	ix = seq & RXRPC_RXTX_BUFF_MASK;
179 	rxrpc_get_skb(skb, rxrpc_skb_got);
180 	call->rxtx_annotations[ix] = annotation;
181 	smp_wmb();
182 	call->rxtx_buffer[ix] = skb;
183 	call->tx_top = seq;
184 	if (last)
185 		trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
186 	else
187 		trace_rxrpc_transmit(call, rxrpc_transmit_queue);
188 
189 	if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
190 		_debug("________awaiting reply/ACK__________");
191 		write_lock_bh(&call->state_lock);
192 		switch (call->state) {
193 		case RXRPC_CALL_CLIENT_SEND_REQUEST:
194 			call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
195 			rxrpc_notify_end_tx(rx, call, notify_end_tx);
196 			break;
197 		case RXRPC_CALL_SERVER_ACK_REQUEST:
198 			call->state = RXRPC_CALL_SERVER_SEND_REPLY;
199 			now = jiffies;
200 			WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
201 			if (call->ackr_reason == RXRPC_ACK_DELAY)
202 				call->ackr_reason = 0;
203 			trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
204 			if (!last)
205 				break;
206 			/* Fall through */
207 		case RXRPC_CALL_SERVER_SEND_REPLY:
208 			call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
209 			rxrpc_notify_end_tx(rx, call, notify_end_tx);
210 			break;
211 		default:
212 			break;
213 		}
214 		write_unlock_bh(&call->state_lock);
215 	}
216 
217 	if (seq == 1 && rxrpc_is_client_call(call))
218 		rxrpc_expose_client_call(call);
219 
220 	ret = rxrpc_send_data_packet(call, skb, false);
221 	if (ret < 0) {
222 		switch (ret) {
223 		case -ENETUNREACH:
224 		case -EHOSTUNREACH:
225 		case -ECONNREFUSED:
226 			rxrpc_set_call_completion(call,
227 						  RXRPC_CALL_LOCAL_ERROR,
228 						  0, ret);
229 			rxrpc_notify_socket(call);
230 			goto out;
231 		}
232 		_debug("need instant resend %d", ret);
233 		rxrpc_instant_resend(call, ix);
234 	} else {
235 		unsigned long now = jiffies, resend_at;
236 
237 		if (call->peer->rtt_usage > 1)
238 			resend_at = nsecs_to_jiffies(call->peer->rtt * 3 / 2);
239 		else
240 			resend_at = rxrpc_resend_timeout;
241 		if (resend_at < 1)
242 			resend_at = 1;
243 
244 		resend_at += now;
245 		WRITE_ONCE(call->resend_at, resend_at);
246 		rxrpc_reduce_call_timer(call, resend_at, now,
247 					rxrpc_timer_set_for_send);
248 	}
249 
250 out:
251 	rxrpc_free_skb(skb, rxrpc_skb_freed);
252 	_leave(" = %d", ret);
253 	return ret;
254 }
255 
256 /*
257  * send data through a socket
258  * - must be called in process context
259  * - The caller holds the call user access mutex, but not the socket lock.
260  */
261 static int rxrpc_send_data(struct rxrpc_sock *rx,
262 			   struct rxrpc_call *call,
263 			   struct msghdr *msg, size_t len,
264 			   rxrpc_notify_end_tx_t notify_end_tx)
265 {
266 	struct rxrpc_skb_priv *sp;
267 	struct sk_buff *skb;
268 	struct sock *sk = &rx->sk;
269 	long timeo;
270 	bool more;
271 	int ret, copied;
272 
273 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
274 
275 	/* this should be in poll */
276 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
277 
278 	if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
279 		return -EPIPE;
280 
281 	more = msg->msg_flags & MSG_MORE;
282 
283 	if (call->tx_total_len != -1) {
284 		if (len > call->tx_total_len)
285 			return -EMSGSIZE;
286 		if (!more && len != call->tx_total_len)
287 			return -EMSGSIZE;
288 	}
289 
290 	skb = call->tx_pending;
291 	call->tx_pending = NULL;
292 	rxrpc_see_skb(skb, rxrpc_skb_seen);
293 
294 	copied = 0;
295 	do {
296 		/* Check to see if there's a ping ACK to reply to. */
297 		if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
298 			rxrpc_send_ack_packet(call, false, NULL);
299 
300 		if (!skb) {
301 			size_t size, chunk, max, space;
302 
303 			_debug("alloc");
304 
305 			if (call->tx_top - call->tx_hard_ack >=
306 			    min_t(unsigned int, call->tx_winsize,
307 				  call->cong_cwnd + call->cong_extra)) {
308 				ret = -EAGAIN;
309 				if (msg->msg_flags & MSG_DONTWAIT)
310 					goto maybe_error;
311 				ret = rxrpc_wait_for_tx_window(rx, call,
312 							       &timeo,
313 							       msg->msg_flags & MSG_WAITALL);
314 				if (ret < 0)
315 					goto maybe_error;
316 			}
317 
318 			max = RXRPC_JUMBO_DATALEN;
319 			max -= call->conn->security_size;
320 			max &= ~(call->conn->size_align - 1UL);
321 
322 			chunk = max;
323 			if (chunk > msg_data_left(msg) && !more)
324 				chunk = msg_data_left(msg);
325 
326 			space = chunk + call->conn->size_align;
327 			space &= ~(call->conn->size_align - 1UL);
328 
329 			size = space + call->conn->security_size;
330 
331 			_debug("SIZE: %zu/%zu/%zu", chunk, space, size);
332 
333 			/* create a buffer that we can retain until it's ACK'd */
334 			skb = sock_alloc_send_skb(
335 				sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
336 			if (!skb)
337 				goto maybe_error;
338 
339 			sp = rxrpc_skb(skb);
340 			sp->rx_flags |= RXRPC_SKB_TX_BUFFER;
341 			rxrpc_new_skb(skb, rxrpc_skb_new);
342 
343 			_debug("ALLOC SEND %p", skb);
344 
345 			ASSERTCMP(skb->mark, ==, 0);
346 
347 			_debug("HS: %u", call->conn->security_size);
348 			skb_reserve(skb, call->conn->security_size);
349 			skb->len += call->conn->security_size;
350 
351 			sp->remain = chunk;
352 			if (sp->remain > skb_tailroom(skb))
353 				sp->remain = skb_tailroom(skb);
354 
355 			_net("skb: hr %d, tr %d, hl %d, rm %d",
356 			       skb_headroom(skb),
357 			       skb_tailroom(skb),
358 			       skb_headlen(skb),
359 			       sp->remain);
360 
361 			skb->ip_summed = CHECKSUM_UNNECESSARY;
362 		}
363 
364 		_debug("append");
365 		sp = rxrpc_skb(skb);
366 
367 		/* append next segment of data to the current buffer */
368 		if (msg_data_left(msg) > 0) {
369 			int copy = skb_tailroom(skb);
370 			ASSERTCMP(copy, >, 0);
371 			if (copy > msg_data_left(msg))
372 				copy = msg_data_left(msg);
373 			if (copy > sp->remain)
374 				copy = sp->remain;
375 
376 			_debug("add");
377 			ret = skb_add_data(skb, &msg->msg_iter, copy);
378 			_debug("added");
379 			if (ret < 0)
380 				goto efault;
381 			sp->remain -= copy;
382 			skb->mark += copy;
383 			copied += copy;
384 			if (call->tx_total_len != -1)
385 				call->tx_total_len -= copy;
386 		}
387 
388 		/* check for the far side aborting the call or a network error
389 		 * occurring */
390 		if (call->state == RXRPC_CALL_COMPLETE)
391 			goto call_terminated;
392 
393 		/* add the packet to the send queue if it's now full */
394 		if (sp->remain <= 0 ||
395 		    (msg_data_left(msg) == 0 && !more)) {
396 			struct rxrpc_connection *conn = call->conn;
397 			uint32_t seq;
398 			size_t pad;
399 
400 			/* pad out if we're using security */
401 			if (conn->security_ix) {
402 				pad = conn->security_size + skb->mark;
403 				pad = conn->size_align - pad;
404 				pad &= conn->size_align - 1;
405 				_debug("pad %zu", pad);
406 				if (pad)
407 					skb_put_zero(skb, pad);
408 			}
409 
410 			seq = call->tx_top + 1;
411 
412 			sp->hdr.seq	= seq;
413 			sp->hdr._rsvd	= 0;
414 			sp->hdr.flags	= conn->out_clientflag;
415 
416 			if (msg_data_left(msg) == 0 && !more)
417 				sp->hdr.flags |= RXRPC_LAST_PACKET;
418 			else if (call->tx_top - call->tx_hard_ack <
419 				 call->tx_winsize)
420 				sp->hdr.flags |= RXRPC_MORE_PACKETS;
421 
422 			ret = conn->security->secure_packet(
423 				call, skb, skb->mark, skb->head);
424 			if (ret < 0)
425 				goto out;
426 
427 			ret = rxrpc_queue_packet(rx, call, skb,
428 						 !msg_data_left(msg) && !more,
429 						 notify_end_tx);
430 			/* Should check for failure here */
431 			skb = NULL;
432 		}
433 	} while (msg_data_left(msg) > 0);
434 
435 success:
436 	ret = copied;
437 out:
438 	call->tx_pending = skb;
439 	_leave(" = %d", ret);
440 	return ret;
441 
442 call_terminated:
443 	rxrpc_free_skb(skb, rxrpc_skb_freed);
444 	_leave(" = %d", call->error);
445 	return call->error;
446 
447 maybe_error:
448 	if (copied)
449 		goto success;
450 	goto out;
451 
452 efault:
453 	ret = -EFAULT;
454 	goto out;
455 }
456 
457 /*
458  * extract control messages from the sendmsg() control buffer
459  */
460 static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
461 {
462 	struct cmsghdr *cmsg;
463 	bool got_user_ID = false;
464 	int len;
465 
466 	if (msg->msg_controllen == 0)
467 		return -EINVAL;
468 
469 	for_each_cmsghdr(cmsg, msg) {
470 		if (!CMSG_OK(msg, cmsg))
471 			return -EINVAL;
472 
473 		len = cmsg->cmsg_len - sizeof(struct cmsghdr);
474 		_debug("CMSG %d, %d, %d",
475 		       cmsg->cmsg_level, cmsg->cmsg_type, len);
476 
477 		if (cmsg->cmsg_level != SOL_RXRPC)
478 			continue;
479 
480 		switch (cmsg->cmsg_type) {
481 		case RXRPC_USER_CALL_ID:
482 			if (msg->msg_flags & MSG_CMSG_COMPAT) {
483 				if (len != sizeof(u32))
484 					return -EINVAL;
485 				p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
486 			} else {
487 				if (len != sizeof(unsigned long))
488 					return -EINVAL;
489 				p->call.user_call_ID = *(unsigned long *)
490 					CMSG_DATA(cmsg);
491 			}
492 			got_user_ID = true;
493 			break;
494 
495 		case RXRPC_ABORT:
496 			if (p->command != RXRPC_CMD_SEND_DATA)
497 				return -EINVAL;
498 			p->command = RXRPC_CMD_SEND_ABORT;
499 			if (len != sizeof(p->abort_code))
500 				return -EINVAL;
501 			p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
502 			if (p->abort_code == 0)
503 				return -EINVAL;
504 			break;
505 
506 		case RXRPC_ACCEPT:
507 			if (p->command != RXRPC_CMD_SEND_DATA)
508 				return -EINVAL;
509 			p->command = RXRPC_CMD_ACCEPT;
510 			if (len != 0)
511 				return -EINVAL;
512 			break;
513 
514 		case RXRPC_EXCLUSIVE_CALL:
515 			p->exclusive = true;
516 			if (len != 0)
517 				return -EINVAL;
518 			break;
519 
520 		case RXRPC_UPGRADE_SERVICE:
521 			p->upgrade = true;
522 			if (len != 0)
523 				return -EINVAL;
524 			break;
525 
526 		case RXRPC_TX_LENGTH:
527 			if (p->call.tx_total_len != -1 || len != sizeof(__s64))
528 				return -EINVAL;
529 			p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
530 			if (p->call.tx_total_len < 0)
531 				return -EINVAL;
532 			break;
533 
534 		case RXRPC_SET_CALL_TIMEOUT:
535 			if (len & 3 || len < 4 || len > 12)
536 				return -EINVAL;
537 			memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
538 			p->call.nr_timeouts = len / 4;
539 			if (p->call.timeouts.hard > INT_MAX / HZ)
540 				return -ERANGE;
541 			if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
542 				return -ERANGE;
543 			if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
544 				return -ERANGE;
545 			break;
546 
547 		default:
548 			return -EINVAL;
549 		}
550 	}
551 
552 	if (!got_user_ID)
553 		return -EINVAL;
554 	if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
555 		return -EINVAL;
556 	_leave(" = 0");
557 	return 0;
558 }
559 
560 /*
561  * Create a new client call for sendmsg().
562  * - Called with the socket lock held, which it must release.
563  * - If it returns a call, the call's lock will need releasing by the caller.
564  */
565 static struct rxrpc_call *
566 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
567 				  struct rxrpc_send_params *p)
568 	__releases(&rx->sk.sk_lock.slock)
569 	__acquires(&call->user_mutex)
570 {
571 	struct rxrpc_conn_parameters cp;
572 	struct rxrpc_call *call;
573 	struct key *key;
574 
575 	DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
576 
577 	_enter("");
578 
579 	if (!msg->msg_name) {
580 		release_sock(&rx->sk);
581 		return ERR_PTR(-EDESTADDRREQ);
582 	}
583 
584 	key = rx->key;
585 	if (key && !rx->key->payload.data[0])
586 		key = NULL;
587 
588 	memset(&cp, 0, sizeof(cp));
589 	cp.local		= rx->local;
590 	cp.key			= rx->key;
591 	cp.security_level	= rx->min_sec_level;
592 	cp.exclusive		= rx->exclusive | p->exclusive;
593 	cp.upgrade		= p->upgrade;
594 	cp.service_id		= srx->srx_service;
595 	call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
596 				     atomic_inc_return(&rxrpc_debug_id));
597 	/* The socket is now unlocked */
598 
599 	rxrpc_put_peer(cp.peer);
600 	_leave(" = %p\n", call);
601 	return call;
602 }
603 
604 /*
605  * send a message forming part of a client call through an RxRPC socket
606  * - caller holds the socket locked
607  * - the socket may be either a client socket or a server socket
608  */
609 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
610 	__releases(&rx->sk.sk_lock.slock)
611 	__releases(&call->user_mutex)
612 {
613 	enum rxrpc_call_state state;
614 	struct rxrpc_call *call;
615 	unsigned long now, j;
616 	int ret;
617 
618 	struct rxrpc_send_params p = {
619 		.call.tx_total_len	= -1,
620 		.call.user_call_ID	= 0,
621 		.call.nr_timeouts	= 0,
622 		.call.intr		= true,
623 		.abort_code		= 0,
624 		.command		= RXRPC_CMD_SEND_DATA,
625 		.exclusive		= false,
626 		.upgrade		= false,
627 	};
628 
629 	_enter("");
630 
631 	ret = rxrpc_sendmsg_cmsg(msg, &p);
632 	if (ret < 0)
633 		goto error_release_sock;
634 
635 	if (p.command == RXRPC_CMD_ACCEPT) {
636 		ret = -EINVAL;
637 		if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
638 			goto error_release_sock;
639 		call = rxrpc_accept_call(rx, p.call.user_call_ID, NULL);
640 		/* The socket is now unlocked. */
641 		if (IS_ERR(call))
642 			return PTR_ERR(call);
643 		ret = 0;
644 		goto out_put_unlock;
645 	}
646 
647 	call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
648 	if (!call) {
649 		ret = -EBADSLT;
650 		if (p.command != RXRPC_CMD_SEND_DATA)
651 			goto error_release_sock;
652 		call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
653 		/* The socket is now unlocked... */
654 		if (IS_ERR(call))
655 			return PTR_ERR(call);
656 		/* ... and we have the call lock. */
657 	} else {
658 		switch (READ_ONCE(call->state)) {
659 		case RXRPC_CALL_UNINITIALISED:
660 		case RXRPC_CALL_CLIENT_AWAIT_CONN:
661 		case RXRPC_CALL_SERVER_PREALLOC:
662 		case RXRPC_CALL_SERVER_SECURING:
663 		case RXRPC_CALL_SERVER_ACCEPTING:
664 			ret = -EBUSY;
665 			goto error_release_sock;
666 		default:
667 			break;
668 		}
669 
670 		ret = mutex_lock_interruptible(&call->user_mutex);
671 		release_sock(&rx->sk);
672 		if (ret < 0) {
673 			ret = -ERESTARTSYS;
674 			goto error_put;
675 		}
676 
677 		if (p.call.tx_total_len != -1) {
678 			ret = -EINVAL;
679 			if (call->tx_total_len != -1 ||
680 			    call->tx_pending ||
681 			    call->tx_top != 0)
682 				goto error_put;
683 			call->tx_total_len = p.call.tx_total_len;
684 		}
685 	}
686 
687 	switch (p.call.nr_timeouts) {
688 	case 3:
689 		j = msecs_to_jiffies(p.call.timeouts.normal);
690 		if (p.call.timeouts.normal > 0 && j == 0)
691 			j = 1;
692 		WRITE_ONCE(call->next_rx_timo, j);
693 		/* Fall through */
694 	case 2:
695 		j = msecs_to_jiffies(p.call.timeouts.idle);
696 		if (p.call.timeouts.idle > 0 && j == 0)
697 			j = 1;
698 		WRITE_ONCE(call->next_req_timo, j);
699 		/* Fall through */
700 	case 1:
701 		if (p.call.timeouts.hard > 0) {
702 			j = msecs_to_jiffies(p.call.timeouts.hard);
703 			now = jiffies;
704 			j += now;
705 			WRITE_ONCE(call->expect_term_by, j);
706 			rxrpc_reduce_call_timer(call, j, now,
707 						rxrpc_timer_set_for_hard);
708 		}
709 		break;
710 	}
711 
712 	state = READ_ONCE(call->state);
713 	_debug("CALL %d USR %lx ST %d on CONN %p",
714 	       call->debug_id, call->user_call_ID, state, call->conn);
715 
716 	if (state >= RXRPC_CALL_COMPLETE) {
717 		/* it's too late for this call */
718 		ret = -ESHUTDOWN;
719 	} else if (p.command == RXRPC_CMD_SEND_ABORT) {
720 		ret = 0;
721 		if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
722 			ret = rxrpc_send_abort_packet(call);
723 	} else if (p.command != RXRPC_CMD_SEND_DATA) {
724 		ret = -EINVAL;
725 	} else if (rxrpc_is_client_call(call) &&
726 		   state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
727 		/* request phase complete for this client call */
728 		ret = -EPROTO;
729 	} else if (rxrpc_is_service_call(call) &&
730 		   state != RXRPC_CALL_SERVER_ACK_REQUEST &&
731 		   state != RXRPC_CALL_SERVER_SEND_REPLY) {
732 		/* Reply phase not begun or not complete for service call. */
733 		ret = -EPROTO;
734 	} else {
735 		ret = rxrpc_send_data(rx, call, msg, len, NULL);
736 	}
737 
738 out_put_unlock:
739 	mutex_unlock(&call->user_mutex);
740 error_put:
741 	rxrpc_put_call(call, rxrpc_call_put);
742 	_leave(" = %d", ret);
743 	return ret;
744 
745 error_release_sock:
746 	release_sock(&rx->sk);
747 	return ret;
748 }
749 
750 /**
751  * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
752  * @sock: The socket the call is on
753  * @call: The call to send data through
754  * @msg: The data to send
755  * @len: The amount of data to send
756  * @notify_end_tx: Notification that the last packet is queued.
757  *
758  * Allow a kernel service to send data on a call.  The call must be in an state
759  * appropriate to sending data.  No control data should be supplied in @msg,
760  * nor should an address be supplied.  MSG_MORE should be flagged if there's
761  * more data to come, otherwise this data will end the transmission phase.
762  */
763 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
764 			   struct msghdr *msg, size_t len,
765 			   rxrpc_notify_end_tx_t notify_end_tx)
766 {
767 	int ret;
768 
769 	_enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
770 
771 	ASSERTCMP(msg->msg_name, ==, NULL);
772 	ASSERTCMP(msg->msg_control, ==, NULL);
773 
774 	mutex_lock(&call->user_mutex);
775 
776 	_debug("CALL %d USR %lx ST %d on CONN %p",
777 	       call->debug_id, call->user_call_ID, call->state, call->conn);
778 
779 	switch (READ_ONCE(call->state)) {
780 	case RXRPC_CALL_CLIENT_SEND_REQUEST:
781 	case RXRPC_CALL_SERVER_ACK_REQUEST:
782 	case RXRPC_CALL_SERVER_SEND_REPLY:
783 		ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
784 				      notify_end_tx);
785 		break;
786 	case RXRPC_CALL_COMPLETE:
787 		read_lock_bh(&call->state_lock);
788 		ret = call->error;
789 		read_unlock_bh(&call->state_lock);
790 		break;
791 	default:
792 		/* Request phase complete for this client call */
793 		trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
794 		ret = -EPROTO;
795 		break;
796 	}
797 
798 	mutex_unlock(&call->user_mutex);
799 	_leave(" = %d", ret);
800 	return ret;
801 }
802 EXPORT_SYMBOL(rxrpc_kernel_send_data);
803 
804 /**
805  * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
806  * @sock: The socket the call is on
807  * @call: The call to be aborted
808  * @abort_code: The abort code to stick into the ABORT packet
809  * @error: Local error value
810  * @why: 3-char string indicating why.
811  *
812  * Allow a kernel service to abort a call, if it's still in an abortable state
813  * and return true if the call was aborted, false if it was already complete.
814  */
815 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
816 			     u32 abort_code, int error, const char *why)
817 {
818 	bool aborted;
819 
820 	_enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
821 
822 	mutex_lock(&call->user_mutex);
823 
824 	aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
825 	if (aborted)
826 		rxrpc_send_abort_packet(call);
827 
828 	mutex_unlock(&call->user_mutex);
829 	return aborted;
830 }
831 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
832 
833 /**
834  * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
835  * @sock: The socket the call is on
836  * @call: The call to be informed
837  * @tx_total_len: The amount of data to be transmitted for this call
838  *
839  * Allow a kernel service to set the total transmit length on a call.  This
840  * allows buffer-to-packet encrypt-and-copy to be performed.
841  *
842  * This function is primarily for use for setting the reply length since the
843  * request length can be set when beginning the call.
844  */
845 void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
846 				s64 tx_total_len)
847 {
848 	WARN_ON(call->tx_total_len != -1);
849 	call->tx_total_len = tx_total_len;
850 }
851 EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);
852