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Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[cris-mirror.git] / net / rxrpc / ar-ack.c
blob16d967075eaf8f1c4cc15ea0ac926cd97277d2d8
1 /* Management of Tx window, Tx resend, ACKs and out-of-sequence reception
2 *
3 * Copyright (C) 2007 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 License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12 #include <linux/module.h>
13 #include <linux/circ_buf.h>
14 #include <linux/net.h>
15 #include <linux/skbuff.h>
16 #include <linux/slab.h>
17 #include <linux/udp.h>
18 #include <net/sock.h>
19 #include <net/af_rxrpc.h>
20 #include "ar-internal.h"
21
22 /*
23 * How long to wait before scheduling ACK generation after seeing a
24 * packet with RXRPC_REQUEST_ACK set (in jiffies).
25 */
26 unsigned int rxrpc_requested_ack_delay = 1;
27
28 /*
29 * How long to wait before scheduling an ACK with subtype DELAY (in jiffies).
30 *
31 * We use this when we've received new data packets. If those packets aren't
32 * all consumed within this time we will send a DELAY ACK if an ACK was not
33 * requested to let the sender know it doesn't need to resend.
34 */
35 unsigned int rxrpc_soft_ack_delay = 1 * HZ;
36
37 /*
38 * How long to wait before scheduling an ACK with subtype IDLE (in jiffies).
39 *
40 * We use this when we've consumed some previously soft-ACK'd packets when
41 * further packets aren't immediately received to decide when to send an IDLE
42 * ACK let the other end know that it can free up its Tx buffer space.
43 */
44 unsigned int rxrpc_idle_ack_delay = 0.5 * HZ;
45
46 /*
47 * Receive window size in packets. This indicates the maximum number of
48 * unconsumed received packets we're willing to retain in memory. Once this
49 * limit is hit, we should generate an EXCEEDS_WINDOW ACK and discard further
50 * packets.
51 */
52 unsigned int rxrpc_rx_window_size = 32;
53
54 /*
55 * Maximum Rx MTU size. This indicates to the sender the size of jumbo packet
56 * made by gluing normal packets together that we're willing to handle.
57 */
58 unsigned int rxrpc_rx_mtu = 5692;
59
60 /*
61 * The maximum number of fragments in a received jumbo packet that we tell the
62 * sender that we're willing to handle.
63 */
64 unsigned int rxrpc_rx_jumbo_max = 4;
65
66 static const char *rxrpc_acks(u8 reason)
67 {
68 static const char *const str[] = {
69 "---", "REQ", "DUP", "OOS", "WIN", "MEM", "PNG", "PNR", "DLY",
70 "IDL", "-?-"
71 };
72
73 if (reason >= ARRAY_SIZE(str))
74 reason = ARRAY_SIZE(str) - 1;
75 return str[reason];
76 }
77
78 static const s8 rxrpc_ack_priority[] = {
79 [0] = 0,
80 [RXRPC_ACK_DELAY] = 1,
81 [RXRPC_ACK_REQUESTED] = 2,
82 [RXRPC_ACK_IDLE] = 3,
83 [RXRPC_ACK_PING_RESPONSE] = 4,
84 [RXRPC_ACK_DUPLICATE] = 5,
85 [RXRPC_ACK_OUT_OF_SEQUENCE] = 6,
86 [RXRPC_ACK_EXCEEDS_WINDOW] = 7,
87 [RXRPC_ACK_NOSPACE] = 8,
88 };
89
90 /*
91 * propose an ACK be sent
92 */
93 void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
94 u32 serial, bool immediate)
95 {
96 unsigned long expiry;
97 s8 prior = rxrpc_ack_priority[ack_reason];
98
99 ASSERTCMP(prior, >, 0);
100
101 _enter("{%d},%s,%%%x,%u",
102 call->debug_id, rxrpc_acks(ack_reason), serial, immediate);
103
104 if (prior < rxrpc_ack_priority[call->ackr_reason]) {
105 if (immediate)
106 goto cancel_timer;
107 return;
108 }
109
110 /* update DELAY, IDLE, REQUESTED and PING_RESPONSE ACK serial
111 * numbers */
112 if (prior == rxrpc_ack_priority[call->ackr_reason]) {
113 if (prior <= 4)
114 call->ackr_serial = serial;
115 if (immediate)
116 goto cancel_timer;
117 return;
118 }
119
120 call->ackr_reason = ack_reason;
121 call->ackr_serial = serial;
122
123 switch (ack_reason) {
124 case RXRPC_ACK_DELAY:
125 _debug("run delay timer");
126 expiry = rxrpc_soft_ack_delay;
127 goto run_timer;
128
129 case RXRPC_ACK_IDLE:
130 if (!immediate) {
131 _debug("run defer timer");
132 expiry = rxrpc_idle_ack_delay;
133 goto run_timer;
134 }
135 goto cancel_timer;
136
137 case RXRPC_ACK_REQUESTED:
138 expiry = rxrpc_requested_ack_delay;
139 if (!expiry)
140 goto cancel_timer;
141 if (!immediate || serial == 1) {
142 _debug("run defer timer");
143 goto run_timer;
144 }
145
146 default:
147 _debug("immediate ACK");
148 goto cancel_timer;
149 }
150
151 run_timer:
152 expiry += jiffies;
153 if (!timer_pending(&call->ack_timer) ||
154 time_after(call->ack_timer.expires, expiry))
155 mod_timer(&call->ack_timer, expiry);
156 return;
157
158 cancel_timer:
159 _debug("cancel timer %%%u", serial);
160 try_to_del_timer_sync(&call->ack_timer);
161 read_lock_bh(&call->state_lock);
162 if (call->state <= RXRPC_CALL_COMPLETE &&
163 !test_and_set_bit(RXRPC_CALL_EV_ACK, &call->events))
164 rxrpc_queue_call(call);
165 read_unlock_bh(&call->state_lock);
166 }
167
168 /*
169 * propose an ACK be sent, locking the call structure
170 */
171 void rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
172 u32 serial, bool immediate)
173 {
174 s8 prior = rxrpc_ack_priority[ack_reason];
175
176 if (prior > rxrpc_ack_priority[call->ackr_reason]) {
177 spin_lock_bh(&call->lock);
178 __rxrpc_propose_ACK(call, ack_reason, serial, immediate);
179 spin_unlock_bh(&call->lock);
180 }
181 }
182
183 /*
184 * set the resend timer
185 */
186 static void rxrpc_set_resend(struct rxrpc_call *call, u8 resend,
187 unsigned long resend_at)
188 {
189 read_lock_bh(&call->state_lock);
190 if (call->state >= RXRPC_CALL_COMPLETE)
191 resend = 0;
192
193 if (resend & 1) {
194 _debug("SET RESEND");
195 set_bit(RXRPC_CALL_EV_RESEND, &call->events);
196 }
197
198 if (resend & 2) {
199 _debug("MODIFY RESEND TIMER");
200 set_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
201 mod_timer(&call->resend_timer, resend_at);
202 } else {
203 _debug("KILL RESEND TIMER");
204 del_timer_sync(&call->resend_timer);
205 clear_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events);
206 clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
207 }
208 read_unlock_bh(&call->state_lock);
209 }
210
211 /*
212 * resend packets
213 */
214 static void rxrpc_resend(struct rxrpc_call *call)
215 {
216 struct rxrpc_wire_header *whdr;
217 struct rxrpc_skb_priv *sp;
218 struct sk_buff *txb;
219 unsigned long *p_txb, resend_at;
220 bool stop;
221 int loop;
222 u8 resend;
223
224 _enter("{%d,%d,%d,%d},",
225 call->acks_hard, call->acks_unacked,
226 atomic_read(&call->sequence),
227 CIRC_CNT(call->acks_head, call->acks_tail, call->acks_winsz));
228
229 stop = false;
230 resend = 0;
231 resend_at = 0;
232
233 for (loop = call->acks_tail;
234 loop != call->acks_head || stop;
235 loop = (loop + 1) & (call->acks_winsz - 1)
236 ) {
237 p_txb = call->acks_window + loop;
238 smp_read_barrier_depends();
239 if (*p_txb & 1)
240 continue;
241
242 txb = (struct sk_buff *) *p_txb;
243 sp = rxrpc_skb(txb);
244
245 if (sp->need_resend) {
246 sp->need_resend = false;
247
248 /* each Tx packet has a new serial number */
249 sp->hdr.serial = atomic_inc_return(&call->conn->serial);
250
251 whdr = (struct rxrpc_wire_header *)txb->head;
252 whdr->serial = htonl(sp->hdr.serial);
253
254 _proto("Tx DATA %%%u { #%d }",
255 sp->hdr.serial, sp->hdr.seq);
256 if (rxrpc_send_packet(call->conn->trans, txb) < 0) {
257 stop = true;
258 sp->resend_at = jiffies + 3;
259 } else {
260 sp->resend_at =
261 jiffies + rxrpc_resend_timeout;
262 }
263 }
264
265 if (time_after_eq(jiffies + 1, sp->resend_at)) {
266 sp->need_resend = true;
267 resend |= 1;
268 } else if (resend & 2) {
269 if (time_before(sp->resend_at, resend_at))
270 resend_at = sp->resend_at;
271 } else {
272 resend_at = sp->resend_at;
273 resend |= 2;
274 }
275 }
276
277 rxrpc_set_resend(call, resend, resend_at);
278 _leave("");
279 }
280
281 /*
282 * handle resend timer expiry
283 */
284 static void rxrpc_resend_timer(struct rxrpc_call *call)
285 {
286 struct rxrpc_skb_priv *sp;
287 struct sk_buff *txb;
288 unsigned long *p_txb, resend_at;
289 int loop;
290 u8 resend;
291
292 _enter("%d,%d,%d",
293 call->acks_tail, call->acks_unacked, call->acks_head);
294
295 if (call->state >= RXRPC_CALL_COMPLETE)
296 return;
297
298 resend = 0;
299 resend_at = 0;
300
301 for (loop = call->acks_unacked;
302 loop != call->acks_head;
303 loop = (loop + 1) & (call->acks_winsz - 1)
304 ) {
305 p_txb = call->acks_window + loop;
306 smp_read_barrier_depends();
307 txb = (struct sk_buff *) (*p_txb & ~1);
308 sp = rxrpc_skb(txb);
309
310 ASSERT(!(*p_txb & 1));
311
312 if (sp->need_resend) {
313 ;
314 } else if (time_after_eq(jiffies + 1, sp->resend_at)) {
315 sp->need_resend = true;
316 resend |= 1;
317 } else if (resend & 2) {
318 if (time_before(sp->resend_at, resend_at))
319 resend_at = sp->resend_at;
320 } else {
321 resend_at = sp->resend_at;
322 resend |= 2;
323 }
324 }
325
326 rxrpc_set_resend(call, resend, resend_at);
327 _leave("");
328 }
329
330 /*
331 * process soft ACKs of our transmitted packets
332 * - these indicate packets the peer has or has not received, but hasn't yet
333 * given to the consumer, and so can still be discarded and re-requested
334 */
335 static int rxrpc_process_soft_ACKs(struct rxrpc_call *call,
336 struct rxrpc_ackpacket *ack,
337 struct sk_buff *skb)
338 {
339 struct rxrpc_skb_priv *sp;
340 struct sk_buff *txb;
341 unsigned long *p_txb, resend_at;
342 int loop;
343 u8 sacks[RXRPC_MAXACKS], resend;
344
345 _enter("{%d,%d},{%d},",
346 call->acks_hard,
347 CIRC_CNT(call->acks_head, call->acks_tail, call->acks_winsz),
348 ack->nAcks);
349
350 if (skb_copy_bits(skb, 0, sacks, ack->nAcks) < 0)
351 goto protocol_error;
352
353 resend = 0;
354 resend_at = 0;
355 for (loop = 0; loop < ack->nAcks; loop++) {
356 p_txb = call->acks_window;
357 p_txb += (call->acks_tail + loop) & (call->acks_winsz - 1);
358 smp_read_barrier_depends();
359 txb = (struct sk_buff *) (*p_txb & ~1);
360 sp = rxrpc_skb(txb);
361
362 switch (sacks[loop]) {
363 case RXRPC_ACK_TYPE_ACK:
364 sp->need_resend = false;
365 *p_txb |= 1;
366 break;
367 case RXRPC_ACK_TYPE_NACK:
368 sp->need_resend = true;
369 *p_txb &= ~1;
370 resend = 1;
371 break;
372 default:
373 _debug("Unsupported ACK type %d", sacks[loop]);
374 goto protocol_error;
375 }
376 }
377
378 smp_mb();
379 call->acks_unacked = (call->acks_tail + loop) & (call->acks_winsz - 1);
380
381 /* anything not explicitly ACK'd is implicitly NACK'd, but may just not
382 * have been received or processed yet by the far end */
383 for (loop = call->acks_unacked;
384 loop != call->acks_head;
385 loop = (loop + 1) & (call->acks_winsz - 1)
386 ) {
387 p_txb = call->acks_window + loop;
388 smp_read_barrier_depends();
389 txb = (struct sk_buff *) (*p_txb & ~1);
390 sp = rxrpc_skb(txb);
391
392 if (*p_txb & 1) {
393 /* packet must have been discarded */
394 sp->need_resend = true;
395 *p_txb &= ~1;
396 resend |= 1;
397 } else if (sp->need_resend) {
398 ;
399 } else if (time_after_eq(jiffies + 1, sp->resend_at)) {
400 sp->need_resend = true;
401 resend |= 1;
402 } else if (resend & 2) {
403 if (time_before(sp->resend_at, resend_at))
404 resend_at = sp->resend_at;
405 } else {
406 resend_at = sp->resend_at;
407 resend |= 2;
408 }
409 }
410
411 rxrpc_set_resend(call, resend, resend_at);
412 _leave(" = 0");
413 return 0;
414
415 protocol_error:
416 _leave(" = -EPROTO");
417 return -EPROTO;
418 }
419
420 /*
421 * discard hard-ACK'd packets from the Tx window
422 */
423 static void rxrpc_rotate_tx_window(struct rxrpc_call *call, u32 hard)
424 {
425 unsigned long _skb;
426 int tail = call->acks_tail, old_tail;
427 int win = CIRC_CNT(call->acks_head, tail, call->acks_winsz);
428
429 kenter("{%u,%u},%u", call->acks_hard, win, hard);
430
431 ASSERTCMP(hard - call->acks_hard, <=, win);
432
433 while (call->acks_hard < hard) {
434 smp_read_barrier_depends();
435 _skb = call->acks_window[tail] & ~1;
436 rxrpc_free_skb((struct sk_buff *) _skb);
437 old_tail = tail;
438 tail = (tail + 1) & (call->acks_winsz - 1);
439 call->acks_tail = tail;
440 if (call->acks_unacked == old_tail)
441 call->acks_unacked = tail;
442 call->acks_hard++;
443 }
444
445 wake_up(&call->tx_waitq);
446 }
447
448 /*
449 * clear the Tx window in the event of a failure
450 */
451 static void rxrpc_clear_tx_window(struct rxrpc_call *call)
452 {
453 rxrpc_rotate_tx_window(call, atomic_read(&call->sequence));
454 }
455
456 /*
457 * drain the out of sequence received packet queue into the packet Rx queue
458 */
459 static int rxrpc_drain_rx_oos_queue(struct rxrpc_call *call)
460 {
461 struct rxrpc_skb_priv *sp;
462 struct sk_buff *skb;
463 bool terminal;
464 int ret;
465
466 _enter("{%d,%d}", call->rx_data_post, call->rx_first_oos);
467
468 spin_lock_bh(&call->lock);
469
470 ret = -ECONNRESET;
471 if (test_bit(RXRPC_CALL_RELEASED, &call->flags))
472 goto socket_unavailable;
473
474 skb = skb_dequeue(&call->rx_oos_queue);
475 if (skb) {
476 sp = rxrpc_skb(skb);
477
478 _debug("drain OOS packet %d [%d]",
479 sp->hdr.seq, call->rx_first_oos);
480
481 if (sp->hdr.seq != call->rx_first_oos) {
482 skb_queue_head(&call->rx_oos_queue, skb);
483 call->rx_first_oos = rxrpc_skb(skb)->hdr.seq;
484 _debug("requeue %p {%u}", skb, call->rx_first_oos);
485 } else {
486 skb->mark = RXRPC_SKB_MARK_DATA;
487 terminal = ((sp->hdr.flags & RXRPC_LAST_PACKET) &&
488 !(sp->hdr.flags & RXRPC_CLIENT_INITIATED));
489 ret = rxrpc_queue_rcv_skb(call, skb, true, terminal);
490 BUG_ON(ret < 0);
491 _debug("drain #%u", call->rx_data_post);
492 call->rx_data_post++;
493
494 /* find out what the next packet is */
495 skb = skb_peek(&call->rx_oos_queue);
496 if (skb)
497 call->rx_first_oos = rxrpc_skb(skb)->hdr.seq;
498 else
499 call->rx_first_oos = 0;
500 _debug("peek %p {%u}", skb, call->rx_first_oos);
501 }
502 }
503
504 ret = 0;
505 socket_unavailable:
506 spin_unlock_bh(&call->lock);
507 _leave(" = %d", ret);
508 return ret;
509 }
510
511 /*
512 * insert an out of sequence packet into the buffer
513 */
514 static void rxrpc_insert_oos_packet(struct rxrpc_call *call,
515 struct sk_buff *skb)
516 {
517 struct rxrpc_skb_priv *sp, *psp;
518 struct sk_buff *p;
519 u32 seq;
520
521 sp = rxrpc_skb(skb);
522 seq = sp->hdr.seq;
523 _enter(",,{%u}", seq);
524
525 skb->destructor = rxrpc_packet_destructor;
526 ASSERTCMP(sp->call, ==, NULL);
527 sp->call = call;
528 rxrpc_get_call(call);
529
530 /* insert into the buffer in sequence order */
531 spin_lock_bh(&call->lock);
532
533 skb_queue_walk(&call->rx_oos_queue, p) {
534 psp = rxrpc_skb(p);
535 if (psp->hdr.seq > seq) {
536 _debug("insert oos #%u before #%u", seq, psp->hdr.seq);
537 skb_insert(p, skb, &call->rx_oos_queue);
538 goto inserted;
539 }
540 }
541
542 _debug("append oos #%u", seq);
543 skb_queue_tail(&call->rx_oos_queue, skb);
544 inserted:
545
546 /* we might now have a new front to the queue */
547 if (call->rx_first_oos == 0 || seq < call->rx_first_oos)
548 call->rx_first_oos = seq;
549
550 read_lock(&call->state_lock);
551 if (call->state < RXRPC_CALL_COMPLETE &&
552 call->rx_data_post == call->rx_first_oos) {
553 _debug("drain rx oos now");
554 set_bit(RXRPC_CALL_EV_DRAIN_RX_OOS, &call->events);
555 }
556 read_unlock(&call->state_lock);
557
558 spin_unlock_bh(&call->lock);
559 _leave(" [stored #%u]", call->rx_first_oos);
560 }
561
562 /*
563 * clear the Tx window on final ACK reception
564 */
565 static void rxrpc_zap_tx_window(struct rxrpc_call *call)
566 {
567 struct rxrpc_skb_priv *sp;
568 struct sk_buff *skb;
569 unsigned long _skb, *acks_window;
570 u8 winsz = call->acks_winsz;
571 int tail;
572
573 acks_window = call->acks_window;
574 call->acks_window = NULL;
575
576 while (CIRC_CNT(call->acks_head, call->acks_tail, winsz) > 0) {
577 tail = call->acks_tail;
578 smp_read_barrier_depends();
579 _skb = acks_window[tail] & ~1;
580 smp_mb();
581 call->acks_tail = (call->acks_tail + 1) & (winsz - 1);
582
583 skb = (struct sk_buff *) _skb;
584 sp = rxrpc_skb(skb);
585 _debug("+++ clear Tx %u", sp->hdr.seq);
586 rxrpc_free_skb(skb);
587 }
588
589 kfree(acks_window);
590 }
591
592 /*
593 * process the extra information that may be appended to an ACK packet
594 */
595 static void rxrpc_extract_ackinfo(struct rxrpc_call *call, struct sk_buff *skb,
596 unsigned int latest, int nAcks)
597 {
598 struct rxrpc_ackinfo ackinfo;
599 struct rxrpc_peer *peer;
600 unsigned int mtu;
601
602 if (skb_copy_bits(skb, nAcks + 3, &ackinfo, sizeof(ackinfo)) < 0) {
603 _leave(" [no ackinfo]");
604 return;
605 }
606
607 _proto("Rx ACK %%%u Info { rx=%u max=%u rwin=%u jm=%u }",
608 latest,
609 ntohl(ackinfo.rxMTU), ntohl(ackinfo.maxMTU),
610 ntohl(ackinfo.rwind), ntohl(ackinfo.jumbo_max));
611
612 mtu = min(ntohl(ackinfo.rxMTU), ntohl(ackinfo.maxMTU));
613
614 peer = call->conn->trans->peer;
615 if (mtu < peer->maxdata) {
616 spin_lock_bh(&peer->lock);
617 peer->maxdata = mtu;
618 peer->mtu = mtu + peer->hdrsize;
619 spin_unlock_bh(&peer->lock);
620 _net("Net MTU %u (maxdata %u)", peer->mtu, peer->maxdata);
621 }
622 }
623
624 /*
625 * process packets in the reception queue
626 */
627 static int rxrpc_process_rx_queue(struct rxrpc_call *call,
628 u32 *_abort_code)
629 {
630 struct rxrpc_ackpacket ack;
631 struct rxrpc_skb_priv *sp;
632 struct sk_buff *skb;
633 bool post_ACK;
634 int latest;
635 u32 hard, tx;
636
637 _enter("");
638
639 process_further:
640 skb = skb_dequeue(&call->rx_queue);
641 if (!skb)
642 return -EAGAIN;
643
644 _net("deferred skb %p", skb);
645
646 sp = rxrpc_skb(skb);
647
648 _debug("process %s [st %d]", rxrpc_pkts[sp->hdr.type], call->state);
649
650 post_ACK = false;
651
652 switch (sp->hdr.type) {
653 /* data packets that wind up here have been received out of
654 * order, need security processing or are jumbo packets */
655 case RXRPC_PACKET_TYPE_DATA:
656 _proto("OOSQ DATA %%%u { #%u }", sp->hdr.serial, sp->hdr.seq);
657
658 /* secured packets must be verified and possibly decrypted */
659 if (rxrpc_verify_packet(call, skb, _abort_code) < 0)
660 goto protocol_error;
661
662 rxrpc_insert_oos_packet(call, skb);
663 goto process_further;
664
665 /* partial ACK to process */
666 case RXRPC_PACKET_TYPE_ACK:
667 if (skb_copy_bits(skb, 0, &ack, sizeof(ack)) < 0) {
668 _debug("extraction failure");
669 goto protocol_error;
670 }
671 if (!skb_pull(skb, sizeof(ack)))
672 BUG();
673
674 latest = sp->hdr.serial;
675 hard = ntohl(ack.firstPacket);
676 tx = atomic_read(&call->sequence);
677
678 _proto("Rx ACK %%%u { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }",
679 latest,
680 ntohs(ack.maxSkew),
681 hard,
682 ntohl(ack.previousPacket),
683 ntohl(ack.serial),
684 rxrpc_acks(ack.reason),
685 ack.nAcks);
686
687 rxrpc_extract_ackinfo(call, skb, latest, ack.nAcks);
688
689 if (ack.reason == RXRPC_ACK_PING) {
690 _proto("Rx ACK %%%u PING Request", latest);
691 rxrpc_propose_ACK(call, RXRPC_ACK_PING_RESPONSE,
692 sp->hdr.serial, true);
693 }
694
695 /* discard any out-of-order or duplicate ACKs */
696 if (latest - call->acks_latest <= 0) {
697 _debug("discard ACK %d <= %d",
698 latest, call->acks_latest);
699 goto discard;
700 }
701 call->acks_latest = latest;
702
703 if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
704 call->state != RXRPC_CALL_CLIENT_AWAIT_REPLY &&
705 call->state != RXRPC_CALL_SERVER_SEND_REPLY &&
706 call->state != RXRPC_CALL_SERVER_AWAIT_ACK)
707 goto discard;
708
709 _debug("Tx=%d H=%u S=%d", tx, call->acks_hard, call->state);
710
711 if (hard > 0) {
712 if (hard - 1 > tx) {
713 _debug("hard-ACK'd packet %d not transmitted"
714 " (%d top)",
715 hard - 1, tx);
716 goto protocol_error;
717 }
718
719 if ((call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY ||
720 call->state == RXRPC_CALL_SERVER_AWAIT_ACK) &&
721 hard > tx) {
722 call->acks_hard = tx;
723 goto all_acked;
724 }
725
726 smp_rmb();
727 rxrpc_rotate_tx_window(call, hard - 1);
728 }
729
730 if (ack.nAcks > 0) {
731 if (hard - 1 + ack.nAcks > tx) {
732 _debug("soft-ACK'd packet %d+%d not"
733 " transmitted (%d top)",
734 hard - 1, ack.nAcks, tx);
735 goto protocol_error;
736 }
737
738 if (rxrpc_process_soft_ACKs(call, &ack, skb) < 0)
739 goto protocol_error;
740 }
741 goto discard;
742
743 /* complete ACK to process */
744 case RXRPC_PACKET_TYPE_ACKALL:
745 goto all_acked;
746
747 /* abort and busy are handled elsewhere */
748 case RXRPC_PACKET_TYPE_BUSY:
749 case RXRPC_PACKET_TYPE_ABORT:
750 BUG();
751
752 /* connection level events - also handled elsewhere */
753 case RXRPC_PACKET_TYPE_CHALLENGE:
754 case RXRPC_PACKET_TYPE_RESPONSE:
755 case RXRPC_PACKET_TYPE_DEBUG:
756 BUG();
757 }
758
759 /* if we've had a hard ACK that covers all the packets we've sent, then
760 * that ends that phase of the operation */
761 all_acked:
762 write_lock_bh(&call->state_lock);
763 _debug("ack all %d", call->state);
764
765 switch (call->state) {
766 case RXRPC_CALL_CLIENT_AWAIT_REPLY:
767 call->state = RXRPC_CALL_CLIENT_RECV_REPLY;
768 break;
769 case RXRPC_CALL_SERVER_AWAIT_ACK:
770 _debug("srv complete");
771 call->state = RXRPC_CALL_COMPLETE;
772 post_ACK = true;
773 break;
774 case RXRPC_CALL_CLIENT_SEND_REQUEST:
775 case RXRPC_CALL_SERVER_RECV_REQUEST:
776 goto protocol_error_unlock; /* can't occur yet */
777 default:
778 write_unlock_bh(&call->state_lock);
779 goto discard; /* assume packet left over from earlier phase */
780 }
781
782 write_unlock_bh(&call->state_lock);
783
784 /* if all the packets we sent are hard-ACK'd, then we can discard
785 * whatever we've got left */
786 _debug("clear Tx %d",
787 CIRC_CNT(call->acks_head, call->acks_tail, call->acks_winsz));
788
789 del_timer_sync(&call->resend_timer);
790 clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
791 clear_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events);
792
793 if (call->acks_window)
794 rxrpc_zap_tx_window(call);
795
796 if (post_ACK) {
797 /* post the final ACK message for userspace to pick up */
798 _debug("post ACK");
799 skb->mark = RXRPC_SKB_MARK_FINAL_ACK;
800 sp->call = call;
801 rxrpc_get_call(call);
802 spin_lock_bh(&call->lock);
803 if (rxrpc_queue_rcv_skb(call, skb, true, true) < 0)
804 BUG();
805 spin_unlock_bh(&call->lock);
806 goto process_further;
807 }
808
809 discard:
810 rxrpc_free_skb(skb);
811 goto process_further;
812
813 protocol_error_unlock:
814 write_unlock_bh(&call->state_lock);
815 protocol_error:
816 rxrpc_free_skb(skb);
817 _leave(" = -EPROTO");
818 return -EPROTO;
819 }
820
821 /*
822 * post a message to the socket Rx queue for recvmsg() to pick up
823 */
824 static int rxrpc_post_message(struct rxrpc_call *call, u32 mark, u32 error,
825 bool fatal)
826 {
827 struct rxrpc_skb_priv *sp;
828 struct sk_buff *skb;
829 int ret;
830
831 _enter("{%d,%lx},%u,%u,%d",
832 call->debug_id, call->flags, mark, error, fatal);
833
834 /* remove timers and things for fatal messages */
835 if (fatal) {
836 del_timer_sync(&call->resend_timer);
837 del_timer_sync(&call->ack_timer);
838 clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
839 }
840
841 if (mark != RXRPC_SKB_MARK_NEW_CALL &&
842 !test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
843 _leave("[no userid]");
844 return 0;
845 }
846
847 if (!test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags)) {
848 skb = alloc_skb(0, GFP_NOFS);
849 if (!skb)
850 return -ENOMEM;
851
852 rxrpc_new_skb(skb);
853
854 skb->mark = mark;
855
856 sp = rxrpc_skb(skb);
857 memset(sp, 0, sizeof(*sp));
858 sp->error = error;
859 sp->call = call;
860 rxrpc_get_call(call);
861
862 spin_lock_bh(&call->lock);
863 ret = rxrpc_queue_rcv_skb(call, skb, true, fatal);
864 spin_unlock_bh(&call->lock);
865 BUG_ON(ret < 0);
866 }
867
868 return 0;
869 }
870
871 /*
872 * handle background processing of incoming call packets and ACK / abort
873 * generation
874 */
875 void rxrpc_process_call(struct work_struct *work)
876 {
877 struct rxrpc_call *call =
878 container_of(work, struct rxrpc_call, processor);
879 struct rxrpc_wire_header whdr;
880 struct rxrpc_ackpacket ack;
881 struct rxrpc_ackinfo ackinfo;
882 struct msghdr msg;
883 struct kvec iov[5];
884 enum rxrpc_call_event genbit;
885 unsigned long bits;
886 __be32 data, pad;
887 size_t len;
888 int loop, nbit, ioc, ret, mtu;
889 u32 serial, abort_code = RX_PROTOCOL_ERROR;
890 u8 *acks = NULL;
891
892 //printk("\n--------------------\n");
893 _enter("{%d,%s,%lx} [%lu]",
894 call->debug_id, rxrpc_call_states[call->state], call->events,
895 (jiffies - call->creation_jif) / (HZ / 10));
896
897 if (test_and_set_bit(RXRPC_CALL_PROC_BUSY, &call->flags)) {
898 _debug("XXXXXXXXXXXXX RUNNING ON MULTIPLE CPUS XXXXXXXXXXXXX");
899 return;
900 }
901
902 /* there's a good chance we're going to have to send a message, so set
903 * one up in advance */
904 msg.msg_name = &call->conn->trans->peer->srx.transport.sin;
905 msg.msg_namelen = sizeof(call->conn->trans->peer->srx.transport.sin);
906 msg.msg_control = NULL;
907 msg.msg_controllen = 0;
908 msg.msg_flags = 0;
909
910 whdr.epoch = htonl(call->conn->epoch);
911 whdr.cid = htonl(call->cid);
912 whdr.callNumber = htonl(call->call_id);
913 whdr.seq = 0;
914 whdr.type = RXRPC_PACKET_TYPE_ACK;
915 whdr.flags = call->conn->out_clientflag;
916 whdr.userStatus = 0;
917 whdr.securityIndex = call->conn->security_ix;
918 whdr._rsvd = 0;
919 whdr.serviceId = htons(call->service_id);
920
921 memset(iov, 0, sizeof(iov));
922 iov[0].iov_base = &whdr;
923 iov[0].iov_len = sizeof(whdr);
924
925 /* deal with events of a final nature */
926 if (test_bit(RXRPC_CALL_EV_RELEASE, &call->events)) {
927 rxrpc_release_call(call);
928 clear_bit(RXRPC_CALL_EV_RELEASE, &call->events);
929 }
930
931 if (test_bit(RXRPC_CALL_EV_RCVD_ERROR, &call->events)) {
932 int error;
933
934 clear_bit(RXRPC_CALL_EV_CONN_ABORT, &call->events);
935 clear_bit(RXRPC_CALL_EV_REJECT_BUSY, &call->events);
936 clear_bit(RXRPC_CALL_EV_ABORT, &call->events);
937
938 error = call->conn->trans->peer->net_error;
939 _debug("post net error %d", error);
940
941 if (rxrpc_post_message(call, RXRPC_SKB_MARK_NET_ERROR,
942 error, true) < 0)
943 goto no_mem;
944 clear_bit(RXRPC_CALL_EV_RCVD_ERROR, &call->events);
945 goto kill_ACKs;
946 }
947
948 if (test_bit(RXRPC_CALL_EV_CONN_ABORT, &call->events)) {
949 ASSERTCMP(call->state, >, RXRPC_CALL_COMPLETE);
950
951 clear_bit(RXRPC_CALL_EV_REJECT_BUSY, &call->events);
952 clear_bit(RXRPC_CALL_EV_ABORT, &call->events);
953
954 _debug("post conn abort");
955
956 if (rxrpc_post_message(call, RXRPC_SKB_MARK_LOCAL_ERROR,
957 call->conn->error, true) < 0)
958 goto no_mem;
959 clear_bit(RXRPC_CALL_EV_CONN_ABORT, &call->events);
960 goto kill_ACKs;
961 }
962
963 if (test_bit(RXRPC_CALL_EV_REJECT_BUSY, &call->events)) {
964 whdr.type = RXRPC_PACKET_TYPE_BUSY;
965 genbit = RXRPC_CALL_EV_REJECT_BUSY;
966 goto send_message;
967 }
968
969 if (test_bit(RXRPC_CALL_EV_ABORT, &call->events)) {
970 ASSERTCMP(call->state, >, RXRPC_CALL_COMPLETE);
971
972 if (rxrpc_post_message(call, RXRPC_SKB_MARK_LOCAL_ERROR,
973 ECONNABORTED, true) < 0)
974 goto no_mem;
975 whdr.type = RXRPC_PACKET_TYPE_ABORT;
976 data = htonl(call->abort_code);
977 iov[1].iov_base = &data;
978 iov[1].iov_len = sizeof(data);
979 genbit = RXRPC_CALL_EV_ABORT;
980 goto send_message;
981 }
982
983 if (test_bit(RXRPC_CALL_EV_ACK_FINAL, &call->events)) {
984 genbit = RXRPC_CALL_EV_ACK_FINAL;
985
986 ack.bufferSpace = htons(8);
987 ack.maxSkew = 0;
988 ack.serial = 0;
989 ack.reason = RXRPC_ACK_IDLE;
990 ack.nAcks = 0;
991 call->ackr_reason = 0;
992
993 spin_lock_bh(&call->lock);
994 ack.serial = htonl(call->ackr_serial);
995 ack.previousPacket = htonl(call->ackr_prev_seq);
996 ack.firstPacket = htonl(call->rx_data_eaten + 1);
997 spin_unlock_bh(&call->lock);
998
999 pad = 0;
1000
1001 iov[1].iov_base = &ack;
1002 iov[1].iov_len = sizeof(ack);
1003 iov[2].iov_base = &pad;
1004 iov[2].iov_len = 3;
1005 iov[3].iov_base = &ackinfo;
1006 iov[3].iov_len = sizeof(ackinfo);
1007 goto send_ACK;
1008 }
1009
1010 if (call->events & ((1 << RXRPC_CALL_EV_RCVD_BUSY) |
1011 (1 << RXRPC_CALL_EV_RCVD_ABORT))
1012 ) {
1013 u32 mark;
1014
1015 if (test_bit(RXRPC_CALL_EV_RCVD_ABORT, &call->events))
1016 mark = RXRPC_SKB_MARK_REMOTE_ABORT;
1017 else
1018 mark = RXRPC_SKB_MARK_BUSY;
1019
1020 _debug("post abort/busy");
1021 rxrpc_clear_tx_window(call);
1022 if (rxrpc_post_message(call, mark, ECONNABORTED, true) < 0)
1023 goto no_mem;
1024
1025 clear_bit(RXRPC_CALL_EV_RCVD_BUSY, &call->events);
1026 clear_bit(RXRPC_CALL_EV_RCVD_ABORT, &call->events);
1027 goto kill_ACKs;
1028 }
1029
1030 if (test_and_clear_bit(RXRPC_CALL_EV_RCVD_ACKALL, &call->events)) {
1031 _debug("do implicit ackall");
1032 rxrpc_clear_tx_window(call);
1033 }
1034
1035 if (test_bit(RXRPC_CALL_EV_LIFE_TIMER, &call->events)) {
1036 write_lock_bh(&call->state_lock);
1037 if (call->state <= RXRPC_CALL_COMPLETE) {
1038 call->state = RXRPC_CALL_LOCALLY_ABORTED;
1039 call->abort_code = RX_CALL_TIMEOUT;
1040 set_bit(RXRPC_CALL_EV_ABORT, &call->events);
1041 }
1042 write_unlock_bh(&call->state_lock);
1043
1044 _debug("post timeout");
1045 if (rxrpc_post_message(call, RXRPC_SKB_MARK_LOCAL_ERROR,
1046 ETIME, true) < 0)
1047 goto no_mem;
1048
1049 clear_bit(RXRPC_CALL_EV_LIFE_TIMER, &call->events);
1050 goto kill_ACKs;
1051 }
1052
1053 /* deal with assorted inbound messages */
1054 if (!skb_queue_empty(&call->rx_queue)) {
1055 switch (rxrpc_process_rx_queue(call, &abort_code)) {
1056 case 0:
1057 case -EAGAIN:
1058 break;
1059 case -ENOMEM:
1060 goto no_mem;
1061 case -EKEYEXPIRED:
1062 case -EKEYREJECTED:
1063 case -EPROTO:
1064 rxrpc_abort_call(call, abort_code);
1065 goto kill_ACKs;
1066 }
1067 }
1068
1069 /* handle resending */
1070 if (test_and_clear_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events))
1071 rxrpc_resend_timer(call);
1072 if (test_and_clear_bit(RXRPC_CALL_EV_RESEND, &call->events))
1073 rxrpc_resend(call);
1074
1075 /* consider sending an ordinary ACK */
1076 if (test_bit(RXRPC_CALL_EV_ACK, &call->events)) {
1077 _debug("send ACK: window: %d - %d { %lx }",
1078 call->rx_data_eaten, call->ackr_win_top,
1079 call->ackr_window[0]);
1080
1081 if (call->state > RXRPC_CALL_SERVER_ACK_REQUEST &&
1082 call->ackr_reason != RXRPC_ACK_PING_RESPONSE) {
1083 /* ACK by sending reply DATA packet in this state */
1084 clear_bit(RXRPC_CALL_EV_ACK, &call->events);
1085 goto maybe_reschedule;
1086 }
1087
1088 genbit = RXRPC_CALL_EV_ACK;
1089
1090 acks = kzalloc(call->ackr_win_top - call->rx_data_eaten,
1091 GFP_NOFS);
1092 if (!acks)
1093 goto no_mem;
1094
1095 //hdr.flags = RXRPC_SLOW_START_OK;
1096 ack.bufferSpace = htons(8);
1097 ack.maxSkew = 0;
1098
1099 spin_lock_bh(&call->lock);
1100 ack.reason = call->ackr_reason;
1101 ack.serial = htonl(call->ackr_serial);
1102 ack.previousPacket = htonl(call->ackr_prev_seq);
1103 ack.firstPacket = htonl(call->rx_data_eaten + 1);
1104
1105 ack.nAcks = 0;
1106 for (loop = 0; loop < RXRPC_ACKR_WINDOW_ASZ; loop++) {
1107 nbit = loop * BITS_PER_LONG;
1108 for (bits = call->ackr_window[loop]; bits; bits >>= 1
1109 ) {
1110 _debug("- l=%d n=%d b=%lx", loop, nbit, bits);
1111 if (bits & 1) {
1112 acks[nbit] = RXRPC_ACK_TYPE_ACK;
1113 ack.nAcks = nbit + 1;
1114 }
1115 nbit++;
1116 }
1117 }
1118 call->ackr_reason = 0;
1119 spin_unlock_bh(&call->lock);
1120
1121 pad = 0;
1122
1123 iov[1].iov_base = &ack;
1124 iov[1].iov_len = sizeof(ack);
1125 iov[2].iov_base = acks;
1126 iov[2].iov_len = ack.nAcks;
1127 iov[3].iov_base = &pad;
1128 iov[3].iov_len = 3;
1129 iov[4].iov_base = &ackinfo;
1130 iov[4].iov_len = sizeof(ackinfo);
1131
1132 switch (ack.reason) {
1133 case RXRPC_ACK_REQUESTED:
1134 case RXRPC_ACK_DUPLICATE:
1135 case RXRPC_ACK_OUT_OF_SEQUENCE:
1136 case RXRPC_ACK_EXCEEDS_WINDOW:
1137 case RXRPC_ACK_NOSPACE:
1138 case RXRPC_ACK_PING:
1139 case RXRPC_ACK_PING_RESPONSE:
1140 goto send_ACK_with_skew;
1141 case RXRPC_ACK_DELAY:
1142 case RXRPC_ACK_IDLE:
1143 goto send_ACK;
1144 }
1145 }
1146
1147 /* handle completion of security negotiations on an incoming
1148 * connection */
1149 if (test_and_clear_bit(RXRPC_CALL_EV_SECURED, &call->events)) {
1150 _debug("secured");
1151 spin_lock_bh(&call->lock);
1152
1153 if (call->state == RXRPC_CALL_SERVER_SECURING) {
1154 _debug("securing");
1155 write_lock(&call->conn->lock);
1156 if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
1157 !test_bit(RXRPC_CALL_EV_RELEASE, &call->events)) {
1158 _debug("not released");
1159 call->state = RXRPC_CALL_SERVER_ACCEPTING;
1160 list_move_tail(&call->accept_link,
1161 &call->socket->acceptq);
1162 }
1163 write_unlock(&call->conn->lock);
1164 read_lock(&call->state_lock);
1165 if (call->state < RXRPC_CALL_COMPLETE)
1166 set_bit(RXRPC_CALL_EV_POST_ACCEPT, &call->events);
1167 read_unlock(&call->state_lock);
1168 }
1169
1170 spin_unlock_bh(&call->lock);
1171 if (!test_bit(RXRPC_CALL_EV_POST_ACCEPT, &call->events))
1172 goto maybe_reschedule;
1173 }
1174
1175 /* post a notification of an acceptable connection to the app */
1176 if (test_bit(RXRPC_CALL_EV_POST_ACCEPT, &call->events)) {
1177 _debug("post accept");
1178 if (rxrpc_post_message(call, RXRPC_SKB_MARK_NEW_CALL,
1179 0, false) < 0)
1180 goto no_mem;
1181 clear_bit(RXRPC_CALL_EV_POST_ACCEPT, &call->events);
1182 goto maybe_reschedule;
1183 }
1184
1185 /* handle incoming call acceptance */
1186 if (test_and_clear_bit(RXRPC_CALL_EV_ACCEPTED, &call->events)) {
1187 _debug("accepted");
1188 ASSERTCMP(call->rx_data_post, ==, 0);
1189 call->rx_data_post = 1;
1190 read_lock_bh(&call->state_lock);
1191 if (call->state < RXRPC_CALL_COMPLETE)
1192 set_bit(RXRPC_CALL_EV_DRAIN_RX_OOS, &call->events);
1193 read_unlock_bh(&call->state_lock);
1194 }
1195
1196 /* drain the out of sequence received packet queue into the packet Rx
1197 * queue */
1198 if (test_and_clear_bit(RXRPC_CALL_EV_DRAIN_RX_OOS, &call->events)) {
1199 while (call->rx_data_post == call->rx_first_oos)
1200 if (rxrpc_drain_rx_oos_queue(call) < 0)
1201 break;
1202 goto maybe_reschedule;
1203 }
1204
1205 /* other events may have been raised since we started checking */
1206 goto maybe_reschedule;
1207
1208 send_ACK_with_skew:
1209 ack.maxSkew = htons(atomic_read(&call->conn->hi_serial) -
1210 ntohl(ack.serial));
1211 send_ACK:
1212 mtu = call->conn->trans->peer->if_mtu;
1213 mtu -= call->conn->trans->peer->hdrsize;
1214 ackinfo.maxMTU = htonl(mtu);
1215 ackinfo.rwind = htonl(rxrpc_rx_window_size);
1216
1217 /* permit the peer to send us jumbo packets if it wants to */
1218 ackinfo.rxMTU = htonl(rxrpc_rx_mtu);
1219 ackinfo.jumbo_max = htonl(rxrpc_rx_jumbo_max);
1220
1221 serial = atomic_inc_return(&call->conn->serial);
1222 whdr.serial = htonl(serial);
1223 _proto("Tx ACK %%%u { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }",
1224 serial,
1225 ntohs(ack.maxSkew),
1226 ntohl(ack.firstPacket),
1227 ntohl(ack.previousPacket),
1228 ntohl(ack.serial),
1229 rxrpc_acks(ack.reason),
1230 ack.nAcks);
1231
1232 del_timer_sync(&call->ack_timer);
1233 if (ack.nAcks > 0)
1234 set_bit(RXRPC_CALL_TX_SOFT_ACK, &call->flags);
1235 goto send_message_2;
1236
1237 send_message:
1238 _debug("send message");
1239
1240 serial = atomic_inc_return(&call->conn->serial);
1241 whdr.serial = htonl(serial);
1242 _proto("Tx %s %%%u", rxrpc_pkts[whdr.type], serial);
1243 send_message_2:
1244
1245 len = iov[0].iov_len;
1246 ioc = 1;
1247 if (iov[4].iov_len) {
1248 ioc = 5;
1249 len += iov[4].iov_len;
1250 len += iov[3].iov_len;
1251 len += iov[2].iov_len;
1252 len += iov[1].iov_len;
1253 } else if (iov[3].iov_len) {
1254 ioc = 4;
1255 len += iov[3].iov_len;
1256 len += iov[2].iov_len;
1257 len += iov[1].iov_len;
1258 } else if (iov[2].iov_len) {
1259 ioc = 3;
1260 len += iov[2].iov_len;
1261 len += iov[1].iov_len;
1262 } else if (iov[1].iov_len) {
1263 ioc = 2;
1264 len += iov[1].iov_len;
1265 }
1266
1267 ret = kernel_sendmsg(call->conn->trans->local->socket,
1268 &msg, iov, ioc, len);
1269 if (ret < 0) {
1270 _debug("sendmsg failed: %d", ret);
1271 read_lock_bh(&call->state_lock);
1272 if (call->state < RXRPC_CALL_DEAD)
1273 rxrpc_queue_call(call);
1274 read_unlock_bh(&call->state_lock);
1275 goto error;
1276 }
1277
1278 switch (genbit) {
1279 case RXRPC_CALL_EV_ABORT:
1280 clear_bit(genbit, &call->events);
1281 clear_bit(RXRPC_CALL_EV_RCVD_ABORT, &call->events);
1282 goto kill_ACKs;
1283
1284 case RXRPC_CALL_EV_ACK_FINAL:
1285 write_lock_bh(&call->state_lock);
1286 if (call->state == RXRPC_CALL_CLIENT_FINAL_ACK)
1287 call->state = RXRPC_CALL_COMPLETE;
1288 write_unlock_bh(&call->state_lock);
1289 goto kill_ACKs;
1290
1291 default:
1292 clear_bit(genbit, &call->events);
1293 switch (call->state) {
1294 case RXRPC_CALL_CLIENT_AWAIT_REPLY:
1295 case RXRPC_CALL_CLIENT_RECV_REPLY:
1296 case RXRPC_CALL_SERVER_RECV_REQUEST:
1297 case RXRPC_CALL_SERVER_ACK_REQUEST:
1298 _debug("start ACK timer");
1299 rxrpc_propose_ACK(call, RXRPC_ACK_DELAY,
1300 call->ackr_serial, false);
1301 default:
1302 break;
1303 }
1304 goto maybe_reschedule;
1305 }
1306
1307 kill_ACKs:
1308 del_timer_sync(&call->ack_timer);
1309 if (test_and_clear_bit(RXRPC_CALL_EV_ACK_FINAL, &call->events))
1310 rxrpc_put_call(call);
1311 clear_bit(RXRPC_CALL_EV_ACK, &call->events);
1312
1313 maybe_reschedule:
1314 if (call->events || !skb_queue_empty(&call->rx_queue)) {
1315 read_lock_bh(&call->state_lock);
1316 if (call->state < RXRPC_CALL_DEAD)
1317 rxrpc_queue_call(call);
1318 read_unlock_bh(&call->state_lock);
1319 }
1320
1321 /* don't leave aborted connections on the accept queue */
1322 if (call->state >= RXRPC_CALL_COMPLETE &&
1323 !list_empty(&call->accept_link)) {
1324 _debug("X unlinking once-pending call %p { e=%lx f=%lx c=%x }",
1325 call, call->events, call->flags, call->conn->cid);
1326
1327 read_lock_bh(&call->state_lock);
1328 if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
1329 !test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events))
1330 rxrpc_queue_call(call);
1331 read_unlock_bh(&call->state_lock);
1332 }
1333
1334 error:
1335 clear_bit(RXRPC_CALL_PROC_BUSY, &call->flags);
1336 kfree(acks);
1337
1338 /* because we don't want two CPUs both processing the work item for one
1339 * call at the same time, we use a flag to note when it's busy; however
1340 * this means there's a race between clearing the flag and setting the
1341 * work pending bit and the work item being processed again */
1342 if (call->events && !work_pending(&call->processor)) {
1343 _debug("jumpstart %x", call->conn->cid);
1344 rxrpc_queue_call(call);
1345 }
1346
1347 _leave("");
1348 return;
1349
1350 no_mem:
1351 _debug("out of memory");
1352 goto maybe_reschedule;
1353 }
CRIS linux kernel tree