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17926a79 DH |
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> | |
5a0e3ad6 | 16 | #include <linux/slab.h> |
17926a79 DH |
17 | #include <linux/udp.h> |
18 | #include <net/sock.h> | |
19 | #include <net/af_rxrpc.h> | |
20 | #include "ar-internal.h" | |
21 | ||
5873c083 DH |
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 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 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 | */ | |
9823f39a | 44 | unsigned rxrpc_idle_ack_delay = 0.5 * HZ; |
17926a79 | 45 | |
817913d8 DH |
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 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 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 rxrpc_rx_jumbo_max = 4; | |
65 | ||
08d4d217 DC |
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 | } | |
17926a79 DH |
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 | */ | |
4e36a95e | 93 | void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, |
17926a79 DH |
94 | __be32 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", | |
08d4d217 | 102 | call->debug_id, rxrpc_acks(ack_reason), ntohl(serial), |
17926a79 DH |
103 | immediate); |
104 | ||
105 | if (prior < rxrpc_ack_priority[call->ackr_reason]) { | |
106 | if (immediate) | |
107 | goto cancel_timer; | |
108 | return; | |
109 | } | |
110 | ||
111 | /* update DELAY, IDLE, REQUESTED and PING_RESPONSE ACK serial | |
112 | * numbers */ | |
113 | if (prior == rxrpc_ack_priority[call->ackr_reason]) { | |
114 | if (prior <= 4) | |
115 | call->ackr_serial = serial; | |
116 | if (immediate) | |
117 | goto cancel_timer; | |
118 | return; | |
119 | } | |
120 | ||
121 | call->ackr_reason = ack_reason; | |
122 | call->ackr_serial = serial; | |
123 | ||
124 | switch (ack_reason) { | |
125 | case RXRPC_ACK_DELAY: | |
126 | _debug("run delay timer"); | |
5873c083 DH |
127 | expiry = rxrpc_soft_ack_delay; |
128 | goto run_timer; | |
17926a79 DH |
129 | |
130 | case RXRPC_ACK_IDLE: | |
131 | if (!immediate) { | |
132 | _debug("run defer timer"); | |
5873c083 | 133 | expiry = rxrpc_idle_ack_delay; |
17926a79 DH |
134 | goto run_timer; |
135 | } | |
136 | goto cancel_timer; | |
137 | ||
138 | case RXRPC_ACK_REQUESTED: | |
5873c083 DH |
139 | expiry = rxrpc_requested_ack_delay; |
140 | if (!expiry) | |
17926a79 DH |
141 | goto cancel_timer; |
142 | if (!immediate || serial == cpu_to_be32(1)) { | |
143 | _debug("run defer timer"); | |
17926a79 DH |
144 | goto run_timer; |
145 | } | |
146 | ||
147 | default: | |
148 | _debug("immediate ACK"); | |
149 | goto cancel_timer; | |
150 | } | |
151 | ||
152 | run_timer: | |
153 | expiry += jiffies; | |
154 | if (!timer_pending(&call->ack_timer) || | |
155 | time_after(call->ack_timer.expires, expiry)) | |
156 | mod_timer(&call->ack_timer, expiry); | |
157 | return; | |
158 | ||
159 | cancel_timer: | |
160 | _debug("cancel timer %%%u", ntohl(serial)); | |
161 | try_to_del_timer_sync(&call->ack_timer); | |
162 | read_lock_bh(&call->state_lock); | |
163 | if (call->state <= RXRPC_CALL_COMPLETE && | |
164 | !test_and_set_bit(RXRPC_CALL_ACK, &call->events)) | |
651350d1 | 165 | rxrpc_queue_call(call); |
17926a79 DH |
166 | read_unlock_bh(&call->state_lock); |
167 | } | |
168 | ||
169 | /* | |
170 | * propose an ACK be sent, locking the call structure | |
171 | */ | |
4e36a95e | 172 | void rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, |
17926a79 DH |
173 | __be32 serial, bool immediate) |
174 | { | |
175 | s8 prior = rxrpc_ack_priority[ack_reason]; | |
176 | ||
177 | if (prior > rxrpc_ack_priority[call->ackr_reason]) { | |
178 | spin_lock_bh(&call->lock); | |
179 | __rxrpc_propose_ACK(call, ack_reason, serial, immediate); | |
180 | spin_unlock_bh(&call->lock); | |
181 | } | |
182 | } | |
183 | ||
184 | /* | |
185 | * set the resend timer | |
186 | */ | |
187 | static void rxrpc_set_resend(struct rxrpc_call *call, u8 resend, | |
188 | unsigned long resend_at) | |
189 | { | |
190 | read_lock_bh(&call->state_lock); | |
191 | if (call->state >= RXRPC_CALL_COMPLETE) | |
192 | resend = 0; | |
193 | ||
194 | if (resend & 1) { | |
195 | _debug("SET RESEND"); | |
196 | set_bit(RXRPC_CALL_RESEND, &call->events); | |
197 | } | |
198 | ||
199 | if (resend & 2) { | |
200 | _debug("MODIFY RESEND TIMER"); | |
201 | set_bit(RXRPC_CALL_RUN_RTIMER, &call->flags); | |
202 | mod_timer(&call->resend_timer, resend_at); | |
203 | } else { | |
204 | _debug("KILL RESEND TIMER"); | |
205 | del_timer_sync(&call->resend_timer); | |
206 | clear_bit(RXRPC_CALL_RESEND_TIMER, &call->events); | |
207 | clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags); | |
208 | } | |
209 | read_unlock_bh(&call->state_lock); | |
210 | } | |
211 | ||
212 | /* | |
213 | * resend packets | |
214 | */ | |
215 | static void rxrpc_resend(struct rxrpc_call *call) | |
216 | { | |
217 | struct rxrpc_skb_priv *sp; | |
218 | struct rxrpc_header *hdr; | |
219 | struct sk_buff *txb; | |
220 | unsigned long *p_txb, resend_at; | |
221 | int loop, stop; | |
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 = 0; | |
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) { | |
3db1cd5c | 246 | sp->need_resend = false; |
17926a79 DH |
247 | |
248 | /* each Tx packet has a new serial number */ | |
249 | sp->hdr.serial = | |
250 | htonl(atomic_inc_return(&call->conn->serial)); | |
251 | ||
252 | hdr = (struct rxrpc_header *) txb->head; | |
253 | hdr->serial = sp->hdr.serial; | |
254 | ||
255 | _proto("Tx DATA %%%u { #%d }", | |
256 | ntohl(sp->hdr.serial), ntohl(sp->hdr.seq)); | |
257 | if (rxrpc_send_packet(call->conn->trans, txb) < 0) { | |
258 | stop = 0; | |
259 | sp->resend_at = jiffies + 3; | |
260 | } else { | |
261 | sp->resend_at = | |
262 | jiffies + rxrpc_resend_timeout * HZ; | |
263 | } | |
264 | } | |
265 | ||
266 | if (time_after_eq(jiffies + 1, sp->resend_at)) { | |
3db1cd5c | 267 | sp->need_resend = true; |
17926a79 DH |
268 | resend |= 1; |
269 | } else if (resend & 2) { | |
270 | if (time_before(sp->resend_at, resend_at)) | |
271 | resend_at = sp->resend_at; | |
272 | } else { | |
273 | resend_at = sp->resend_at; | |
274 | resend |= 2; | |
275 | } | |
276 | } | |
277 | ||
278 | rxrpc_set_resend(call, resend, resend_at); | |
279 | _leave(""); | |
280 | } | |
281 | ||
282 | /* | |
283 | * handle resend timer expiry | |
284 | */ | |
285 | static void rxrpc_resend_timer(struct rxrpc_call *call) | |
286 | { | |
287 | struct rxrpc_skb_priv *sp; | |
288 | struct sk_buff *txb; | |
289 | unsigned long *p_txb, resend_at; | |
290 | int loop; | |
291 | u8 resend; | |
292 | ||
293 | _enter("%d,%d,%d", | |
294 | call->acks_tail, call->acks_unacked, call->acks_head); | |
295 | ||
3b5bac2b DH |
296 | if (call->state >= RXRPC_CALL_COMPLETE) |
297 | return; | |
298 | ||
17926a79 DH |
299 | resend = 0; |
300 | resend_at = 0; | |
301 | ||
302 | for (loop = call->acks_unacked; | |
303 | loop != call->acks_head; | |
304 | loop = (loop + 1) & (call->acks_winsz - 1) | |
305 | ) { | |
306 | p_txb = call->acks_window + loop; | |
307 | smp_read_barrier_depends(); | |
308 | txb = (struct sk_buff *) (*p_txb & ~1); | |
309 | sp = rxrpc_skb(txb); | |
310 | ||
311 | ASSERT(!(*p_txb & 1)); | |
312 | ||
313 | if (sp->need_resend) { | |
314 | ; | |
315 | } else if (time_after_eq(jiffies + 1, sp->resend_at)) { | |
3db1cd5c | 316 | sp->need_resend = true; |
17926a79 DH |
317 | resend |= 1; |
318 | } else if (resend & 2) { | |
319 | if (time_before(sp->resend_at, resend_at)) | |
320 | resend_at = sp->resend_at; | |
321 | } else { | |
322 | resend_at = sp->resend_at; | |
323 | resend |= 2; | |
324 | } | |
325 | } | |
326 | ||
327 | rxrpc_set_resend(call, resend, resend_at); | |
328 | _leave(""); | |
329 | } | |
330 | ||
331 | /* | |
332 | * process soft ACKs of our transmitted packets | |
333 | * - these indicate packets the peer has or has not received, but hasn't yet | |
334 | * given to the consumer, and so can still be discarded and re-requested | |
335 | */ | |
336 | static int rxrpc_process_soft_ACKs(struct rxrpc_call *call, | |
337 | struct rxrpc_ackpacket *ack, | |
338 | struct sk_buff *skb) | |
339 | { | |
340 | struct rxrpc_skb_priv *sp; | |
341 | struct sk_buff *txb; | |
342 | unsigned long *p_txb, resend_at; | |
343 | int loop; | |
344 | u8 sacks[RXRPC_MAXACKS], resend; | |
345 | ||
346 | _enter("{%d,%d},{%d},", | |
347 | call->acks_hard, | |
348 | CIRC_CNT(call->acks_head, call->acks_tail, call->acks_winsz), | |
349 | ack->nAcks); | |
350 | ||
351 | if (skb_copy_bits(skb, 0, sacks, ack->nAcks) < 0) | |
352 | goto protocol_error; | |
353 | ||
354 | resend = 0; | |
355 | resend_at = 0; | |
356 | for (loop = 0; loop < ack->nAcks; loop++) { | |
357 | p_txb = call->acks_window; | |
358 | p_txb += (call->acks_tail + loop) & (call->acks_winsz - 1); | |
359 | smp_read_barrier_depends(); | |
360 | txb = (struct sk_buff *) (*p_txb & ~1); | |
361 | sp = rxrpc_skb(txb); | |
362 | ||
363 | switch (sacks[loop]) { | |
364 | case RXRPC_ACK_TYPE_ACK: | |
3db1cd5c | 365 | sp->need_resend = false; |
17926a79 DH |
366 | *p_txb |= 1; |
367 | break; | |
368 | case RXRPC_ACK_TYPE_NACK: | |
3db1cd5c | 369 | sp->need_resend = true; |
17926a79 DH |
370 | *p_txb &= ~1; |
371 | resend = 1; | |
372 | break; | |
373 | default: | |
374 | _debug("Unsupported ACK type %d", sacks[loop]); | |
375 | goto protocol_error; | |
376 | } | |
377 | } | |
378 | ||
379 | smp_mb(); | |
380 | call->acks_unacked = (call->acks_tail + loop) & (call->acks_winsz - 1); | |
381 | ||
382 | /* anything not explicitly ACK'd is implicitly NACK'd, but may just not | |
383 | * have been received or processed yet by the far end */ | |
384 | for (loop = call->acks_unacked; | |
385 | loop != call->acks_head; | |
386 | loop = (loop + 1) & (call->acks_winsz - 1) | |
387 | ) { | |
388 | p_txb = call->acks_window + loop; | |
389 | smp_read_barrier_depends(); | |
390 | txb = (struct sk_buff *) (*p_txb & ~1); | |
391 | sp = rxrpc_skb(txb); | |
392 | ||
393 | if (*p_txb & 1) { | |
394 | /* packet must have been discarded */ | |
3db1cd5c | 395 | sp->need_resend = true; |
17926a79 DH |
396 | *p_txb &= ~1; |
397 | resend |= 1; | |
398 | } else if (sp->need_resend) { | |
399 | ; | |
400 | } else if (time_after_eq(jiffies + 1, sp->resend_at)) { | |
3db1cd5c | 401 | sp->need_resend = true; |
17926a79 DH |
402 | resend |= 1; |
403 | } else if (resend & 2) { | |
404 | if (time_before(sp->resend_at, resend_at)) | |
405 | resend_at = sp->resend_at; | |
406 | } else { | |
407 | resend_at = sp->resend_at; | |
408 | resend |= 2; | |
409 | } | |
410 | } | |
411 | ||
412 | rxrpc_set_resend(call, resend, resend_at); | |
413 | _leave(" = 0"); | |
414 | return 0; | |
415 | ||
416 | protocol_error: | |
417 | _leave(" = -EPROTO"); | |
418 | return -EPROTO; | |
419 | } | |
420 | ||
421 | /* | |
422 | * discard hard-ACK'd packets from the Tx window | |
423 | */ | |
424 | static void rxrpc_rotate_tx_window(struct rxrpc_call *call, u32 hard) | |
425 | { | |
17926a79 DH |
426 | unsigned long _skb; |
427 | int tail = call->acks_tail, old_tail; | |
428 | int win = CIRC_CNT(call->acks_head, tail, call->acks_winsz); | |
429 | ||
430 | _enter("{%u,%u},%u", call->acks_hard, win, hard); | |
431 | ||
432 | ASSERTCMP(hard - call->acks_hard, <=, win); | |
433 | ||
434 | while (call->acks_hard < hard) { | |
435 | smp_read_barrier_depends(); | |
436 | _skb = call->acks_window[tail] & ~1; | |
17926a79 DH |
437 | rxrpc_free_skb((struct sk_buff *) _skb); |
438 | old_tail = tail; | |
439 | tail = (tail + 1) & (call->acks_winsz - 1); | |
440 | call->acks_tail = tail; | |
441 | if (call->acks_unacked == old_tail) | |
442 | call->acks_unacked = tail; | |
443 | call->acks_hard++; | |
444 | } | |
445 | ||
446 | wake_up(&call->tx_waitq); | |
447 | } | |
448 | ||
449 | /* | |
450 | * clear the Tx window in the event of a failure | |
451 | */ | |
452 | static void rxrpc_clear_tx_window(struct rxrpc_call *call) | |
453 | { | |
454 | rxrpc_rotate_tx_window(call, atomic_read(&call->sequence)); | |
455 | } | |
456 | ||
457 | /* | |
458 | * drain the out of sequence received packet queue into the packet Rx queue | |
459 | */ | |
460 | static int rxrpc_drain_rx_oos_queue(struct rxrpc_call *call) | |
461 | { | |
462 | struct rxrpc_skb_priv *sp; | |
463 | struct sk_buff *skb; | |
464 | bool terminal; | |
465 | int ret; | |
466 | ||
467 | _enter("{%d,%d}", call->rx_data_post, call->rx_first_oos); | |
468 | ||
469 | spin_lock_bh(&call->lock); | |
470 | ||
471 | ret = -ECONNRESET; | |
472 | if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) | |
473 | goto socket_unavailable; | |
474 | ||
475 | skb = skb_dequeue(&call->rx_oos_queue); | |
476 | if (skb) { | |
477 | sp = rxrpc_skb(skb); | |
478 | ||
479 | _debug("drain OOS packet %d [%d]", | |
480 | ntohl(sp->hdr.seq), call->rx_first_oos); | |
481 | ||
482 | if (ntohl(sp->hdr.seq) != call->rx_first_oos) { | |
483 | skb_queue_head(&call->rx_oos_queue, skb); | |
484 | call->rx_first_oos = ntohl(rxrpc_skb(skb)->hdr.seq); | |
485 | _debug("requeue %p {%u}", skb, call->rx_first_oos); | |
486 | } else { | |
487 | skb->mark = RXRPC_SKB_MARK_DATA; | |
488 | terminal = ((sp->hdr.flags & RXRPC_LAST_PACKET) && | |
489 | !(sp->hdr.flags & RXRPC_CLIENT_INITIATED)); | |
490 | ret = rxrpc_queue_rcv_skb(call, skb, true, terminal); | |
491 | BUG_ON(ret < 0); | |
492 | _debug("drain #%u", call->rx_data_post); | |
493 | call->rx_data_post++; | |
494 | ||
495 | /* find out what the next packet is */ | |
496 | skb = skb_peek(&call->rx_oos_queue); | |
497 | if (skb) | |
498 | call->rx_first_oos = | |
499 | ntohl(rxrpc_skb(skb)->hdr.seq); | |
500 | else | |
501 | call->rx_first_oos = 0; | |
502 | _debug("peek %p {%u}", skb, call->rx_first_oos); | |
503 | } | |
504 | } | |
505 | ||
506 | ret = 0; | |
507 | socket_unavailable: | |
508 | spin_unlock_bh(&call->lock); | |
509 | _leave(" = %d", ret); | |
510 | return ret; | |
511 | } | |
512 | ||
513 | /* | |
514 | * insert an out of sequence packet into the buffer | |
515 | */ | |
516 | static void rxrpc_insert_oos_packet(struct rxrpc_call *call, | |
517 | struct sk_buff *skb) | |
518 | { | |
519 | struct rxrpc_skb_priv *sp, *psp; | |
520 | struct sk_buff *p; | |
521 | u32 seq; | |
522 | ||
523 | sp = rxrpc_skb(skb); | |
524 | seq = ntohl(sp->hdr.seq); | |
525 | _enter(",,{%u}", seq); | |
526 | ||
527 | skb->destructor = rxrpc_packet_destructor; | |
528 | ASSERTCMP(sp->call, ==, NULL); | |
529 | sp->call = call; | |
530 | rxrpc_get_call(call); | |
531 | ||
532 | /* insert into the buffer in sequence order */ | |
533 | spin_lock_bh(&call->lock); | |
534 | ||
535 | skb_queue_walk(&call->rx_oos_queue, p) { | |
536 | psp = rxrpc_skb(p); | |
537 | if (ntohl(psp->hdr.seq) > seq) { | |
538 | _debug("insert oos #%u before #%u", | |
539 | seq, ntohl(psp->hdr.seq)); | |
540 | skb_insert(p, skb, &call->rx_oos_queue); | |
541 | goto inserted; | |
542 | } | |
543 | } | |
544 | ||
545 | _debug("append oos #%u", seq); | |
546 | skb_queue_tail(&call->rx_oos_queue, skb); | |
547 | inserted: | |
548 | ||
549 | /* we might now have a new front to the queue */ | |
550 | if (call->rx_first_oos == 0 || seq < call->rx_first_oos) | |
551 | call->rx_first_oos = seq; | |
552 | ||
553 | read_lock(&call->state_lock); | |
554 | if (call->state < RXRPC_CALL_COMPLETE && | |
555 | call->rx_data_post == call->rx_first_oos) { | |
556 | _debug("drain rx oos now"); | |
557 | set_bit(RXRPC_CALL_DRAIN_RX_OOS, &call->events); | |
558 | } | |
559 | read_unlock(&call->state_lock); | |
560 | ||
561 | spin_unlock_bh(&call->lock); | |
562 | _leave(" [stored #%u]", call->rx_first_oos); | |
563 | } | |
564 | ||
565 | /* | |
566 | * clear the Tx window on final ACK reception | |
567 | */ | |
568 | static void rxrpc_zap_tx_window(struct rxrpc_call *call) | |
569 | { | |
570 | struct rxrpc_skb_priv *sp; | |
571 | struct sk_buff *skb; | |
572 | unsigned long _skb, *acks_window; | |
4e36a95e | 573 | u8 winsz = call->acks_winsz; |
17926a79 DH |
574 | int tail; |
575 | ||
576 | acks_window = call->acks_window; | |
577 | call->acks_window = NULL; | |
578 | ||
579 | while (CIRC_CNT(call->acks_head, call->acks_tail, winsz) > 0) { | |
580 | tail = call->acks_tail; | |
581 | smp_read_barrier_depends(); | |
582 | _skb = acks_window[tail] & ~1; | |
583 | smp_mb(); | |
584 | call->acks_tail = (call->acks_tail + 1) & (winsz - 1); | |
585 | ||
586 | skb = (struct sk_buff *) _skb; | |
587 | sp = rxrpc_skb(skb); | |
588 | _debug("+++ clear Tx %u", ntohl(sp->hdr.seq)); | |
589 | rxrpc_free_skb(skb); | |
590 | } | |
591 | ||
592 | kfree(acks_window); | |
593 | } | |
594 | ||
224711df DH |
595 | /* |
596 | * process the extra information that may be appended to an ACK packet | |
597 | */ | |
598 | static void rxrpc_extract_ackinfo(struct rxrpc_call *call, struct sk_buff *skb, | |
95c96174 | 599 | unsigned int latest, int nAcks) |
224711df DH |
600 | { |
601 | struct rxrpc_ackinfo ackinfo; | |
602 | struct rxrpc_peer *peer; | |
95c96174 | 603 | unsigned int mtu; |
224711df DH |
604 | |
605 | if (skb_copy_bits(skb, nAcks + 3, &ackinfo, sizeof(ackinfo)) < 0) { | |
606 | _leave(" [no ackinfo]"); | |
607 | return; | |
608 | } | |
609 | ||
610 | _proto("Rx ACK %%%u Info { rx=%u max=%u rwin=%u jm=%u }", | |
611 | latest, | |
612 | ntohl(ackinfo.rxMTU), ntohl(ackinfo.maxMTU), | |
613 | ntohl(ackinfo.rwind), ntohl(ackinfo.jumbo_max)); | |
614 | ||
615 | mtu = min(ntohl(ackinfo.rxMTU), ntohl(ackinfo.maxMTU)); | |
616 | ||
617 | peer = call->conn->trans->peer; | |
618 | if (mtu < peer->maxdata) { | |
619 | spin_lock_bh(&peer->lock); | |
620 | peer->maxdata = mtu; | |
621 | peer->mtu = mtu + peer->hdrsize; | |
622 | spin_unlock_bh(&peer->lock); | |
623 | _net("Net MTU %u (maxdata %u)", peer->mtu, peer->maxdata); | |
624 | } | |
625 | } | |
626 | ||
17926a79 DH |
627 | /* |
628 | * process packets in the reception queue | |
629 | */ | |
630 | static int rxrpc_process_rx_queue(struct rxrpc_call *call, | |
631 | u32 *_abort_code) | |
632 | { | |
633 | struct rxrpc_ackpacket ack; | |
634 | struct rxrpc_skb_priv *sp; | |
635 | struct sk_buff *skb; | |
636 | bool post_ACK; | |
637 | int latest; | |
638 | u32 hard, tx; | |
639 | ||
640 | _enter(""); | |
641 | ||
642 | process_further: | |
643 | skb = skb_dequeue(&call->rx_queue); | |
644 | if (!skb) | |
645 | return -EAGAIN; | |
646 | ||
647 | _net("deferred skb %p", skb); | |
648 | ||
649 | sp = rxrpc_skb(skb); | |
650 | ||
651 | _debug("process %s [st %d]", rxrpc_pkts[sp->hdr.type], call->state); | |
652 | ||
653 | post_ACK = false; | |
654 | ||
655 | switch (sp->hdr.type) { | |
656 | /* data packets that wind up here have been received out of | |
657 | * order, need security processing or are jumbo packets */ | |
658 | case RXRPC_PACKET_TYPE_DATA: | |
659 | _proto("OOSQ DATA %%%u { #%u }", | |
660 | ntohl(sp->hdr.serial), ntohl(sp->hdr.seq)); | |
661 | ||
662 | /* secured packets must be verified and possibly decrypted */ | |
663 | if (rxrpc_verify_packet(call, skb, _abort_code) < 0) | |
664 | goto protocol_error; | |
665 | ||
666 | rxrpc_insert_oos_packet(call, skb); | |
667 | goto process_further; | |
668 | ||
669 | /* partial ACK to process */ | |
670 | case RXRPC_PACKET_TYPE_ACK: | |
671 | if (skb_copy_bits(skb, 0, &ack, sizeof(ack)) < 0) { | |
672 | _debug("extraction failure"); | |
673 | goto protocol_error; | |
674 | } | |
675 | if (!skb_pull(skb, sizeof(ack))) | |
676 | BUG(); | |
677 | ||
678 | latest = ntohl(sp->hdr.serial); | |
679 | hard = ntohl(ack.firstPacket); | |
680 | tx = atomic_read(&call->sequence); | |
681 | ||
682 | _proto("Rx ACK %%%u { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }", | |
683 | latest, | |
684 | ntohs(ack.maxSkew), | |
685 | hard, | |
686 | ntohl(ack.previousPacket), | |
687 | ntohl(ack.serial), | |
08d4d217 | 688 | rxrpc_acks(ack.reason), |
17926a79 DH |
689 | ack.nAcks); |
690 | ||
224711df DH |
691 | rxrpc_extract_ackinfo(call, skb, latest, ack.nAcks); |
692 | ||
17926a79 DH |
693 | if (ack.reason == RXRPC_ACK_PING) { |
694 | _proto("Rx ACK %%%u PING Request", latest); | |
695 | rxrpc_propose_ACK(call, RXRPC_ACK_PING_RESPONSE, | |
696 | sp->hdr.serial, true); | |
697 | } | |
698 | ||
699 | /* discard any out-of-order or duplicate ACKs */ | |
700 | if (latest - call->acks_latest <= 0) { | |
701 | _debug("discard ACK %d <= %d", | |
702 | latest, call->acks_latest); | |
703 | goto discard; | |
704 | } | |
705 | call->acks_latest = latest; | |
706 | ||
707 | if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST && | |
708 | call->state != RXRPC_CALL_CLIENT_AWAIT_REPLY && | |
709 | call->state != RXRPC_CALL_SERVER_SEND_REPLY && | |
710 | call->state != RXRPC_CALL_SERVER_AWAIT_ACK) | |
711 | goto discard; | |
712 | ||
713 | _debug("Tx=%d H=%u S=%d", tx, call->acks_hard, call->state); | |
714 | ||
715 | if (hard > 0) { | |
716 | if (hard - 1 > tx) { | |
717 | _debug("hard-ACK'd packet %d not transmitted" | |
718 | " (%d top)", | |
719 | hard - 1, tx); | |
720 | goto protocol_error; | |
721 | } | |
722 | ||
723 | if ((call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY || | |
724 | call->state == RXRPC_CALL_SERVER_AWAIT_ACK) && | |
725 | hard > tx) | |
726 | goto all_acked; | |
727 | ||
728 | smp_rmb(); | |
729 | rxrpc_rotate_tx_window(call, hard - 1); | |
730 | } | |
731 | ||
732 | if (ack.nAcks > 0) { | |
733 | if (hard - 1 + ack.nAcks > tx) { | |
734 | _debug("soft-ACK'd packet %d+%d not" | |
735 | " transmitted (%d top)", | |
736 | hard - 1, ack.nAcks, tx); | |
737 | goto protocol_error; | |
738 | } | |
739 | ||
740 | if (rxrpc_process_soft_ACKs(call, &ack, skb) < 0) | |
741 | goto protocol_error; | |
742 | } | |
743 | goto discard; | |
744 | ||
745 | /* complete ACK to process */ | |
746 | case RXRPC_PACKET_TYPE_ACKALL: | |
747 | goto all_acked; | |
748 | ||
749 | /* abort and busy are handled elsewhere */ | |
750 | case RXRPC_PACKET_TYPE_BUSY: | |
751 | case RXRPC_PACKET_TYPE_ABORT: | |
752 | BUG(); | |
753 | ||
754 | /* connection level events - also handled elsewhere */ | |
755 | case RXRPC_PACKET_TYPE_CHALLENGE: | |
756 | case RXRPC_PACKET_TYPE_RESPONSE: | |
757 | case RXRPC_PACKET_TYPE_DEBUG: | |
758 | BUG(); | |
759 | } | |
760 | ||
761 | /* if we've had a hard ACK that covers all the packets we've sent, then | |
762 | * that ends that phase of the operation */ | |
763 | all_acked: | |
764 | write_lock_bh(&call->state_lock); | |
765 | _debug("ack all %d", call->state); | |
766 | ||
767 | switch (call->state) { | |
768 | case RXRPC_CALL_CLIENT_AWAIT_REPLY: | |
769 | call->state = RXRPC_CALL_CLIENT_RECV_REPLY; | |
770 | break; | |
771 | case RXRPC_CALL_SERVER_AWAIT_ACK: | |
772 | _debug("srv complete"); | |
773 | call->state = RXRPC_CALL_COMPLETE; | |
774 | post_ACK = true; | |
775 | break; | |
776 | case RXRPC_CALL_CLIENT_SEND_REQUEST: | |
777 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
778 | goto protocol_error_unlock; /* can't occur yet */ | |
779 | default: | |
780 | write_unlock_bh(&call->state_lock); | |
781 | goto discard; /* assume packet left over from earlier phase */ | |
782 | } | |
783 | ||
784 | write_unlock_bh(&call->state_lock); | |
785 | ||
786 | /* if all the packets we sent are hard-ACK'd, then we can discard | |
787 | * whatever we've got left */ | |
788 | _debug("clear Tx %d", | |
789 | CIRC_CNT(call->acks_head, call->acks_tail, call->acks_winsz)); | |
790 | ||
791 | del_timer_sync(&call->resend_timer); | |
792 | clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags); | |
793 | clear_bit(RXRPC_CALL_RESEND_TIMER, &call->events); | |
794 | ||
795 | if (call->acks_window) | |
796 | rxrpc_zap_tx_window(call); | |
797 | ||
798 | if (post_ACK) { | |
799 | /* post the final ACK message for userspace to pick up */ | |
800 | _debug("post ACK"); | |
801 | skb->mark = RXRPC_SKB_MARK_FINAL_ACK; | |
802 | sp->call = call; | |
803 | rxrpc_get_call(call); | |
804 | spin_lock_bh(&call->lock); | |
805 | if (rxrpc_queue_rcv_skb(call, skb, true, true) < 0) | |
806 | BUG(); | |
807 | spin_unlock_bh(&call->lock); | |
808 | goto process_further; | |
809 | } | |
810 | ||
811 | discard: | |
812 | rxrpc_free_skb(skb); | |
813 | goto process_further; | |
814 | ||
815 | protocol_error_unlock: | |
816 | write_unlock_bh(&call->state_lock); | |
817 | protocol_error: | |
818 | rxrpc_free_skb(skb); | |
819 | _leave(" = -EPROTO"); | |
820 | return -EPROTO; | |
821 | } | |
822 | ||
823 | /* | |
824 | * post a message to the socket Rx queue for recvmsg() to pick up | |
825 | */ | |
826 | static int rxrpc_post_message(struct rxrpc_call *call, u32 mark, u32 error, | |
827 | bool fatal) | |
828 | { | |
829 | struct rxrpc_skb_priv *sp; | |
830 | struct sk_buff *skb; | |
831 | int ret; | |
832 | ||
833 | _enter("{%d,%lx},%u,%u,%d", | |
834 | call->debug_id, call->flags, mark, error, fatal); | |
835 | ||
836 | /* remove timers and things for fatal messages */ | |
837 | if (fatal) { | |
838 | del_timer_sync(&call->resend_timer); | |
839 | del_timer_sync(&call->ack_timer); | |
840 | clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags); | |
841 | } | |
842 | ||
843 | if (mark != RXRPC_SKB_MARK_NEW_CALL && | |
844 | !test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { | |
845 | _leave("[no userid]"); | |
846 | return 0; | |
847 | } | |
848 | ||
849 | if (!test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags)) { | |
850 | skb = alloc_skb(0, GFP_NOFS); | |
851 | if (!skb) | |
852 | return -ENOMEM; | |
853 | ||
854 | rxrpc_new_skb(skb); | |
855 | ||
856 | skb->mark = mark; | |
857 | ||
858 | sp = rxrpc_skb(skb); | |
859 | memset(sp, 0, sizeof(*sp)); | |
860 | sp->error = error; | |
861 | sp->call = call; | |
862 | rxrpc_get_call(call); | |
863 | ||
864 | spin_lock_bh(&call->lock); | |
865 | ret = rxrpc_queue_rcv_skb(call, skb, true, fatal); | |
866 | spin_unlock_bh(&call->lock); | |
163e3cb7 | 867 | BUG_ON(ret < 0); |
17926a79 DH |
868 | } |
869 | ||
870 | return 0; | |
871 | } | |
872 | ||
873 | /* | |
874 | * handle background processing of incoming call packets and ACK / abort | |
875 | * generation | |
876 | */ | |
877 | void rxrpc_process_call(struct work_struct *work) | |
878 | { | |
879 | struct rxrpc_call *call = | |
880 | container_of(work, struct rxrpc_call, processor); | |
881 | struct rxrpc_ackpacket ack; | |
882 | struct rxrpc_ackinfo ackinfo; | |
883 | struct rxrpc_header hdr; | |
884 | struct msghdr msg; | |
885 | struct kvec iov[5]; | |
886 | unsigned long bits; | |
224711df | 887 | __be32 data, pad; |
17926a79 | 888 | size_t len; |
224711df | 889 | int genbit, loop, nbit, ioc, ret, mtu; |
17926a79 DH |
890 | u32 abort_code = RX_PROTOCOL_ERROR; |
891 | u8 *acks = NULL; | |
892 | ||
893 | //printk("\n--------------------\n"); | |
894 | _enter("{%d,%s,%lx} [%lu]", | |
895 | call->debug_id, rxrpc_call_states[call->state], call->events, | |
896 | (jiffies - call->creation_jif) / (HZ / 10)); | |
897 | ||
898 | if (test_and_set_bit(RXRPC_CALL_PROC_BUSY, &call->flags)) { | |
899 | _debug("XXXXXXXXXXXXX RUNNING ON MULTIPLE CPUS XXXXXXXXXXXXX"); | |
900 | return; | |
901 | } | |
902 | ||
903 | /* there's a good chance we're going to have to send a message, so set | |
904 | * one up in advance */ | |
905 | msg.msg_name = &call->conn->trans->peer->srx.transport.sin; | |
906 | msg.msg_namelen = sizeof(call->conn->trans->peer->srx.transport.sin); | |
907 | msg.msg_control = NULL; | |
908 | msg.msg_controllen = 0; | |
909 | msg.msg_flags = 0; | |
910 | ||
911 | hdr.epoch = call->conn->epoch; | |
912 | hdr.cid = call->cid; | |
913 | hdr.callNumber = call->call_id; | |
914 | hdr.seq = 0; | |
915 | hdr.type = RXRPC_PACKET_TYPE_ACK; | |
916 | hdr.flags = call->conn->out_clientflag; | |
917 | hdr.userStatus = 0; | |
918 | hdr.securityIndex = call->conn->security_ix; | |
919 | hdr._rsvd = 0; | |
920 | hdr.serviceId = call->conn->service_id; | |
921 | ||
922 | memset(iov, 0, sizeof(iov)); | |
923 | iov[0].iov_base = &hdr; | |
924 | iov[0].iov_len = sizeof(hdr); | |
925 | ||
926 | /* deal with events of a final nature */ | |
927 | if (test_bit(RXRPC_CALL_RELEASE, &call->events)) { | |
928 | rxrpc_release_call(call); | |
929 | clear_bit(RXRPC_CALL_RELEASE, &call->events); | |
930 | } | |
931 | ||
932 | if (test_bit(RXRPC_CALL_RCVD_ERROR, &call->events)) { | |
933 | int error; | |
934 | ||
935 | clear_bit(RXRPC_CALL_CONN_ABORT, &call->events); | |
936 | clear_bit(RXRPC_CALL_REJECT_BUSY, &call->events); | |
937 | clear_bit(RXRPC_CALL_ABORT, &call->events); | |
938 | ||
939 | error = call->conn->trans->peer->net_error; | |
940 | _debug("post net error %d", error); | |
941 | ||
942 | if (rxrpc_post_message(call, RXRPC_SKB_MARK_NET_ERROR, | |
943 | error, true) < 0) | |
944 | goto no_mem; | |
945 | clear_bit(RXRPC_CALL_RCVD_ERROR, &call->events); | |
946 | goto kill_ACKs; | |
947 | } | |
948 | ||
949 | if (test_bit(RXRPC_CALL_CONN_ABORT, &call->events)) { | |
950 | ASSERTCMP(call->state, >, RXRPC_CALL_COMPLETE); | |
951 | ||
952 | clear_bit(RXRPC_CALL_REJECT_BUSY, &call->events); | |
953 | clear_bit(RXRPC_CALL_ABORT, &call->events); | |
954 | ||
955 | _debug("post conn abort"); | |
956 | ||
957 | if (rxrpc_post_message(call, RXRPC_SKB_MARK_LOCAL_ERROR, | |
958 | call->conn->error, true) < 0) | |
959 | goto no_mem; | |
960 | clear_bit(RXRPC_CALL_CONN_ABORT, &call->events); | |
961 | goto kill_ACKs; | |
962 | } | |
963 | ||
964 | if (test_bit(RXRPC_CALL_REJECT_BUSY, &call->events)) { | |
965 | hdr.type = RXRPC_PACKET_TYPE_BUSY; | |
966 | genbit = RXRPC_CALL_REJECT_BUSY; | |
967 | goto send_message; | |
968 | } | |
969 | ||
970 | if (test_bit(RXRPC_CALL_ABORT, &call->events)) { | |
971 | ASSERTCMP(call->state, >, RXRPC_CALL_COMPLETE); | |
972 | ||
973 | if (rxrpc_post_message(call, RXRPC_SKB_MARK_LOCAL_ERROR, | |
974 | ECONNABORTED, true) < 0) | |
975 | goto no_mem; | |
976 | hdr.type = RXRPC_PACKET_TYPE_ABORT; | |
977 | data = htonl(call->abort_code); | |
978 | iov[1].iov_base = &data; | |
979 | iov[1].iov_len = sizeof(data); | |
980 | genbit = RXRPC_CALL_ABORT; | |
981 | goto send_message; | |
982 | } | |
983 | ||
984 | if (test_bit(RXRPC_CALL_ACK_FINAL, &call->events)) { | |
17926a79 | 985 | genbit = RXRPC_CALL_ACK_FINAL; |
224711df DH |
986 | |
987 | ack.bufferSpace = htons(8); | |
988 | ack.maxSkew = 0; | |
989 | ack.serial = 0; | |
990 | ack.reason = RXRPC_ACK_IDLE; | |
991 | ack.nAcks = 0; | |
992 | call->ackr_reason = 0; | |
993 | ||
994 | spin_lock_bh(&call->lock); | |
995 | ack.serial = call->ackr_serial; | |
996 | ack.previousPacket = call->ackr_prev_seq; | |
997 | ack.firstPacket = htonl(call->rx_data_eaten + 1); | |
998 | spin_unlock_bh(&call->lock); | |
999 | ||
1000 | pad = 0; | |
1001 | ||
1002 | iov[1].iov_base = &ack; | |
1003 | iov[1].iov_len = sizeof(ack); | |
1004 | iov[2].iov_base = &pad; | |
1005 | iov[2].iov_len = 3; | |
1006 | iov[3].iov_base = &ackinfo; | |
1007 | iov[3].iov_len = sizeof(ackinfo); | |
1008 | goto send_ACK; | |
17926a79 DH |
1009 | } |
1010 | ||
1011 | if (call->events & ((1 << RXRPC_CALL_RCVD_BUSY) | | |
1012 | (1 << RXRPC_CALL_RCVD_ABORT)) | |
1013 | ) { | |
1014 | u32 mark; | |
1015 | ||
1016 | if (test_bit(RXRPC_CALL_RCVD_ABORT, &call->events)) | |
1017 | mark = RXRPC_SKB_MARK_REMOTE_ABORT; | |
1018 | else | |
1019 | mark = RXRPC_SKB_MARK_BUSY; | |
1020 | ||
1021 | _debug("post abort/busy"); | |
1022 | rxrpc_clear_tx_window(call); | |
1023 | if (rxrpc_post_message(call, mark, ECONNABORTED, true) < 0) | |
1024 | goto no_mem; | |
1025 | ||
1026 | clear_bit(RXRPC_CALL_RCVD_BUSY, &call->events); | |
1027 | clear_bit(RXRPC_CALL_RCVD_ABORT, &call->events); | |
1028 | goto kill_ACKs; | |
1029 | } | |
1030 | ||
1031 | if (test_and_clear_bit(RXRPC_CALL_RCVD_ACKALL, &call->events)) { | |
1032 | _debug("do implicit ackall"); | |
1033 | rxrpc_clear_tx_window(call); | |
1034 | } | |
1035 | ||
1036 | if (test_bit(RXRPC_CALL_LIFE_TIMER, &call->events)) { | |
1037 | write_lock_bh(&call->state_lock); | |
1038 | if (call->state <= RXRPC_CALL_COMPLETE) { | |
1039 | call->state = RXRPC_CALL_LOCALLY_ABORTED; | |
1040 | call->abort_code = RX_CALL_TIMEOUT; | |
1041 | set_bit(RXRPC_CALL_ABORT, &call->events); | |
1042 | } | |
1043 | write_unlock_bh(&call->state_lock); | |
1044 | ||
1045 | _debug("post timeout"); | |
1046 | if (rxrpc_post_message(call, RXRPC_SKB_MARK_LOCAL_ERROR, | |
1047 | ETIME, true) < 0) | |
1048 | goto no_mem; | |
1049 | ||
1050 | clear_bit(RXRPC_CALL_LIFE_TIMER, &call->events); | |
1051 | goto kill_ACKs; | |
1052 | } | |
1053 | ||
1054 | /* deal with assorted inbound messages */ | |
1055 | if (!skb_queue_empty(&call->rx_queue)) { | |
1056 | switch (rxrpc_process_rx_queue(call, &abort_code)) { | |
1057 | case 0: | |
1058 | case -EAGAIN: | |
1059 | break; | |
1060 | case -ENOMEM: | |
1061 | goto no_mem; | |
1062 | case -EKEYEXPIRED: | |
1063 | case -EKEYREJECTED: | |
1064 | case -EPROTO: | |
1065 | rxrpc_abort_call(call, abort_code); | |
1066 | goto kill_ACKs; | |
1067 | } | |
1068 | } | |
1069 | ||
1070 | /* handle resending */ | |
1071 | if (test_and_clear_bit(RXRPC_CALL_RESEND_TIMER, &call->events)) | |
1072 | rxrpc_resend_timer(call); | |
1073 | if (test_and_clear_bit(RXRPC_CALL_RESEND, &call->events)) | |
1074 | rxrpc_resend(call); | |
1075 | ||
1076 | /* consider sending an ordinary ACK */ | |
1077 | if (test_bit(RXRPC_CALL_ACK, &call->events)) { | |
17926a79 DH |
1078 | _debug("send ACK: window: %d - %d { %lx }", |
1079 | call->rx_data_eaten, call->ackr_win_top, | |
1080 | call->ackr_window[0]); | |
1081 | ||
1082 | if (call->state > RXRPC_CALL_SERVER_ACK_REQUEST && | |
1083 | call->ackr_reason != RXRPC_ACK_PING_RESPONSE) { | |
1084 | /* ACK by sending reply DATA packet in this state */ | |
1085 | clear_bit(RXRPC_CALL_ACK, &call->events); | |
1086 | goto maybe_reschedule; | |
1087 | } | |
1088 | ||
1089 | genbit = RXRPC_CALL_ACK; | |
1090 | ||
1091 | acks = kzalloc(call->ackr_win_top - call->rx_data_eaten, | |
1092 | GFP_NOFS); | |
1093 | if (!acks) | |
1094 | goto no_mem; | |
1095 | ||
1096 | //hdr.flags = RXRPC_SLOW_START_OK; | |
1097 | ack.bufferSpace = htons(8); | |
1098 | ack.maxSkew = 0; | |
1099 | ack.serial = 0; | |
1100 | ack.reason = 0; | |
1101 | ||
17926a79 DH |
1102 | spin_lock_bh(&call->lock); |
1103 | ack.reason = call->ackr_reason; | |
1104 | ack.serial = call->ackr_serial; | |
1105 | ack.previousPacket = call->ackr_prev_seq; | |
1106 | ack.firstPacket = htonl(call->rx_data_eaten + 1); | |
1107 | ||
1108 | ack.nAcks = 0; | |
1109 | for (loop = 0; loop < RXRPC_ACKR_WINDOW_ASZ; loop++) { | |
1110 | nbit = loop * BITS_PER_LONG; | |
1111 | for (bits = call->ackr_window[loop]; bits; bits >>= 1 | |
1112 | ) { | |
1113 | _debug("- l=%d n=%d b=%lx", loop, nbit, bits); | |
1114 | if (bits & 1) { | |
1115 | acks[nbit] = RXRPC_ACK_TYPE_ACK; | |
1116 | ack.nAcks = nbit + 1; | |
1117 | } | |
1118 | nbit++; | |
1119 | } | |
1120 | } | |
1121 | call->ackr_reason = 0; | |
1122 | spin_unlock_bh(&call->lock); | |
1123 | ||
1124 | pad = 0; | |
1125 | ||
1126 | iov[1].iov_base = &ack; | |
1127 | iov[1].iov_len = sizeof(ack); | |
1128 | iov[2].iov_base = acks; | |
1129 | iov[2].iov_len = ack.nAcks; | |
1130 | iov[3].iov_base = &pad; | |
1131 | iov[3].iov_len = 3; | |
1132 | iov[4].iov_base = &ackinfo; | |
1133 | iov[4].iov_len = sizeof(ackinfo); | |
1134 | ||
1135 | switch (ack.reason) { | |
1136 | case RXRPC_ACK_REQUESTED: | |
1137 | case RXRPC_ACK_DUPLICATE: | |
1138 | case RXRPC_ACK_OUT_OF_SEQUENCE: | |
1139 | case RXRPC_ACK_EXCEEDS_WINDOW: | |
1140 | case RXRPC_ACK_NOSPACE: | |
1141 | case RXRPC_ACK_PING: | |
1142 | case RXRPC_ACK_PING_RESPONSE: | |
1143 | goto send_ACK_with_skew; | |
1144 | case RXRPC_ACK_DELAY: | |
1145 | case RXRPC_ACK_IDLE: | |
1146 | goto send_ACK; | |
1147 | } | |
1148 | } | |
1149 | ||
1150 | /* handle completion of security negotiations on an incoming | |
1151 | * connection */ | |
1152 | if (test_and_clear_bit(RXRPC_CALL_SECURED, &call->events)) { | |
1153 | _debug("secured"); | |
1154 | spin_lock_bh(&call->lock); | |
1155 | ||
1156 | if (call->state == RXRPC_CALL_SERVER_SECURING) { | |
1157 | _debug("securing"); | |
1158 | write_lock(&call->conn->lock); | |
1159 | if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) && | |
1160 | !test_bit(RXRPC_CALL_RELEASE, &call->events)) { | |
1161 | _debug("not released"); | |
1162 | call->state = RXRPC_CALL_SERVER_ACCEPTING; | |
1163 | list_move_tail(&call->accept_link, | |
1164 | &call->socket->acceptq); | |
1165 | } | |
1166 | write_unlock(&call->conn->lock); | |
1167 | read_lock(&call->state_lock); | |
1168 | if (call->state < RXRPC_CALL_COMPLETE) | |
1169 | set_bit(RXRPC_CALL_POST_ACCEPT, &call->events); | |
1170 | read_unlock(&call->state_lock); | |
1171 | } | |
1172 | ||
1173 | spin_unlock_bh(&call->lock); | |
1174 | if (!test_bit(RXRPC_CALL_POST_ACCEPT, &call->events)) | |
1175 | goto maybe_reschedule; | |
1176 | } | |
1177 | ||
1178 | /* post a notification of an acceptable connection to the app */ | |
1179 | if (test_bit(RXRPC_CALL_POST_ACCEPT, &call->events)) { | |
1180 | _debug("post accept"); | |
1181 | if (rxrpc_post_message(call, RXRPC_SKB_MARK_NEW_CALL, | |
1182 | 0, false) < 0) | |
1183 | goto no_mem; | |
1184 | clear_bit(RXRPC_CALL_POST_ACCEPT, &call->events); | |
1185 | goto maybe_reschedule; | |
1186 | } | |
1187 | ||
1188 | /* handle incoming call acceptance */ | |
1189 | if (test_and_clear_bit(RXRPC_CALL_ACCEPTED, &call->events)) { | |
1190 | _debug("accepted"); | |
1191 | ASSERTCMP(call->rx_data_post, ==, 0); | |
1192 | call->rx_data_post = 1; | |
1193 | read_lock_bh(&call->state_lock); | |
1194 | if (call->state < RXRPC_CALL_COMPLETE) | |
1195 | set_bit(RXRPC_CALL_DRAIN_RX_OOS, &call->events); | |
1196 | read_unlock_bh(&call->state_lock); | |
1197 | } | |
1198 | ||
1199 | /* drain the out of sequence received packet queue into the packet Rx | |
1200 | * queue */ | |
1201 | if (test_and_clear_bit(RXRPC_CALL_DRAIN_RX_OOS, &call->events)) { | |
1202 | while (call->rx_data_post == call->rx_first_oos) | |
1203 | if (rxrpc_drain_rx_oos_queue(call) < 0) | |
1204 | break; | |
1205 | goto maybe_reschedule; | |
1206 | } | |
1207 | ||
1208 | /* other events may have been raised since we started checking */ | |
1209 | goto maybe_reschedule; | |
1210 | ||
1211 | send_ACK_with_skew: | |
1212 | ack.maxSkew = htons(atomic_read(&call->conn->hi_serial) - | |
1213 | ntohl(ack.serial)); | |
1214 | send_ACK: | |
224711df DH |
1215 | mtu = call->conn->trans->peer->if_mtu; |
1216 | mtu -= call->conn->trans->peer->hdrsize; | |
1217 | ackinfo.maxMTU = htonl(mtu); | |
817913d8 | 1218 | ackinfo.rwind = htonl(rxrpc_rx_window_size); |
224711df DH |
1219 | |
1220 | /* permit the peer to send us jumbo packets if it wants to */ | |
817913d8 DH |
1221 | ackinfo.rxMTU = htonl(rxrpc_rx_mtu); |
1222 | ackinfo.jumbo_max = htonl(rxrpc_rx_jumbo_max); | |
224711df | 1223 | |
17926a79 DH |
1224 | hdr.serial = htonl(atomic_inc_return(&call->conn->serial)); |
1225 | _proto("Tx ACK %%%u { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }", | |
1226 | ntohl(hdr.serial), | |
1227 | ntohs(ack.maxSkew), | |
1228 | ntohl(ack.firstPacket), | |
1229 | ntohl(ack.previousPacket), | |
1230 | ntohl(ack.serial), | |
08d4d217 | 1231 | rxrpc_acks(ack.reason), |
17926a79 DH |
1232 | ack.nAcks); |
1233 | ||
1234 | del_timer_sync(&call->ack_timer); | |
1235 | if (ack.nAcks > 0) | |
1236 | set_bit(RXRPC_CALL_TX_SOFT_ACK, &call->flags); | |
1237 | goto send_message_2; | |
1238 | ||
1239 | send_message: | |
1240 | _debug("send message"); | |
1241 | ||
1242 | hdr.serial = htonl(atomic_inc_return(&call->conn->serial)); | |
1243 | _proto("Tx %s %%%u", rxrpc_pkts[hdr.type], ntohl(hdr.serial)); | |
1244 | send_message_2: | |
1245 | ||
1246 | len = iov[0].iov_len; | |
1247 | ioc = 1; | |
1248 | if (iov[4].iov_len) { | |
1249 | ioc = 5; | |
1250 | len += iov[4].iov_len; | |
1251 | len += iov[3].iov_len; | |
1252 | len += iov[2].iov_len; | |
1253 | len += iov[1].iov_len; | |
1254 | } else if (iov[3].iov_len) { | |
1255 | ioc = 4; | |
1256 | len += iov[3].iov_len; | |
1257 | len += iov[2].iov_len; | |
1258 | len += iov[1].iov_len; | |
1259 | } else if (iov[2].iov_len) { | |
1260 | ioc = 3; | |
1261 | len += iov[2].iov_len; | |
1262 | len += iov[1].iov_len; | |
1263 | } else if (iov[1].iov_len) { | |
1264 | ioc = 2; | |
1265 | len += iov[1].iov_len; | |
1266 | } | |
1267 | ||
1268 | ret = kernel_sendmsg(call->conn->trans->local->socket, | |
1269 | &msg, iov, ioc, len); | |
1270 | if (ret < 0) { | |
1271 | _debug("sendmsg failed: %d", ret); | |
1272 | read_lock_bh(&call->state_lock); | |
1273 | if (call->state < RXRPC_CALL_DEAD) | |
651350d1 | 1274 | rxrpc_queue_call(call); |
17926a79 DH |
1275 | read_unlock_bh(&call->state_lock); |
1276 | goto error; | |
1277 | } | |
1278 | ||
1279 | switch (genbit) { | |
1280 | case RXRPC_CALL_ABORT: | |
1281 | clear_bit(genbit, &call->events); | |
1282 | clear_bit(RXRPC_CALL_RCVD_ABORT, &call->events); | |
1283 | goto kill_ACKs; | |
1284 | ||
1285 | case RXRPC_CALL_ACK_FINAL: | |
1286 | write_lock_bh(&call->state_lock); | |
1287 | if (call->state == RXRPC_CALL_CLIENT_FINAL_ACK) | |
1288 | call->state = RXRPC_CALL_COMPLETE; | |
1289 | write_unlock_bh(&call->state_lock); | |
1290 | goto kill_ACKs; | |
1291 | ||
1292 | default: | |
1293 | clear_bit(genbit, &call->events); | |
1294 | switch (call->state) { | |
1295 | case RXRPC_CALL_CLIENT_AWAIT_REPLY: | |
1296 | case RXRPC_CALL_CLIENT_RECV_REPLY: | |
1297 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
1298 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
1299 | _debug("start ACK timer"); | |
1300 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, | |
1301 | call->ackr_serial, false); | |
1302 | default: | |
1303 | break; | |
1304 | } | |
1305 | goto maybe_reschedule; | |
1306 | } | |
1307 | ||
1308 | kill_ACKs: | |
1309 | del_timer_sync(&call->ack_timer); | |
1310 | if (test_and_clear_bit(RXRPC_CALL_ACK_FINAL, &call->events)) | |
1311 | rxrpc_put_call(call); | |
1312 | clear_bit(RXRPC_CALL_ACK, &call->events); | |
1313 | ||
1314 | maybe_reschedule: | |
1315 | if (call->events || !skb_queue_empty(&call->rx_queue)) { | |
1316 | read_lock_bh(&call->state_lock); | |
1317 | if (call->state < RXRPC_CALL_DEAD) | |
651350d1 | 1318 | rxrpc_queue_call(call); |
17926a79 DH |
1319 | read_unlock_bh(&call->state_lock); |
1320 | } | |
1321 | ||
1322 | /* don't leave aborted connections on the accept queue */ | |
1323 | if (call->state >= RXRPC_CALL_COMPLETE && | |
1324 | !list_empty(&call->accept_link)) { | |
1325 | _debug("X unlinking once-pending call %p { e=%lx f=%lx c=%x }", | |
1326 | call, call->events, call->flags, | |
1327 | ntohl(call->conn->cid)); | |
1328 | ||
1329 | read_lock_bh(&call->state_lock); | |
1330 | if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) && | |
1331 | !test_and_set_bit(RXRPC_CALL_RELEASE, &call->events)) | |
651350d1 | 1332 | rxrpc_queue_call(call); |
17926a79 DH |
1333 | read_unlock_bh(&call->state_lock); |
1334 | } | |
1335 | ||
1336 | error: | |
1337 | clear_bit(RXRPC_CALL_PROC_BUSY, &call->flags); | |
1338 | kfree(acks); | |
1339 | ||
1340 | /* because we don't want two CPUs both processing the work item for one | |
1341 | * call at the same time, we use a flag to note when it's busy; however | |
1342 | * this means there's a race between clearing the flag and setting the | |
1343 | * work pending bit and the work item being processed again */ | |
1344 | if (call->events && !work_pending(&call->processor)) { | |
1345 | _debug("jumpstart %x", ntohl(call->conn->cid)); | |
651350d1 | 1346 | rxrpc_queue_call(call); |
17926a79 DH |
1347 | } |
1348 | ||
1349 | _leave(""); | |
1350 | return; | |
1351 | ||
1352 | no_mem: | |
1353 | _debug("out of memory"); | |
1354 | goto maybe_reschedule; | |
1355 | } |