of: MSI: Simplify irqdomain lookup
[linux/fpc-iii.git] / net / rxrpc / ar-output.c
blob14c4e12c47b0f87f1c560d752bbd897d3ae2f952
1 /* RxRPC packet transmission
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
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.
12 #include <linux/net.h>
13 #include <linux/gfp.h>
14 #include <linux/skbuff.h>
15 #include <linux/circ_buf.h>
16 #include <linux/export.h>
17 #include <net/sock.h>
18 #include <net/af_rxrpc.h>
19 #include "ar-internal.h"
22 * Time till packet resend (in jiffies).
24 unsigned rxrpc_resend_timeout = 4 * HZ;
26 static int rxrpc_send_data(struct rxrpc_sock *rx,
27 struct rxrpc_call *call,
28 struct msghdr *msg, size_t len);
31 * extract control messages from the sendmsg() control buffer
33 static int rxrpc_sendmsg_cmsg(struct rxrpc_sock *rx, struct msghdr *msg,
34 unsigned long *user_call_ID,
35 enum rxrpc_command *command,
36 u32 *abort_code,
37 bool server)
39 struct cmsghdr *cmsg;
40 int len;
42 *command = RXRPC_CMD_SEND_DATA;
44 if (msg->msg_controllen == 0)
45 return -EINVAL;
47 for_each_cmsghdr(cmsg, msg) {
48 if (!CMSG_OK(msg, cmsg))
49 return -EINVAL;
51 len = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
52 _debug("CMSG %d, %d, %d",
53 cmsg->cmsg_level, cmsg->cmsg_type, len);
55 if (cmsg->cmsg_level != SOL_RXRPC)
56 continue;
58 switch (cmsg->cmsg_type) {
59 case RXRPC_USER_CALL_ID:
60 if (msg->msg_flags & MSG_CMSG_COMPAT) {
61 if (len != sizeof(u32))
62 return -EINVAL;
63 *user_call_ID = *(u32 *) CMSG_DATA(cmsg);
64 } else {
65 if (len != sizeof(unsigned long))
66 return -EINVAL;
67 *user_call_ID = *(unsigned long *)
68 CMSG_DATA(cmsg);
70 _debug("User Call ID %lx", *user_call_ID);
71 break;
73 case RXRPC_ABORT:
74 if (*command != RXRPC_CMD_SEND_DATA)
75 return -EINVAL;
76 *command = RXRPC_CMD_SEND_ABORT;
77 if (len != sizeof(*abort_code))
78 return -EINVAL;
79 *abort_code = *(unsigned int *) CMSG_DATA(cmsg);
80 _debug("Abort %x", *abort_code);
81 if (*abort_code == 0)
82 return -EINVAL;
83 break;
85 case RXRPC_ACCEPT:
86 if (*command != RXRPC_CMD_SEND_DATA)
87 return -EINVAL;
88 *command = RXRPC_CMD_ACCEPT;
89 if (len != 0)
90 return -EINVAL;
91 if (!server)
92 return -EISCONN;
93 break;
95 default:
96 return -EINVAL;
100 _leave(" = 0");
101 return 0;
105 * abort a call, sending an ABORT packet to the peer
107 static void rxrpc_send_abort(struct rxrpc_call *call, u32 abort_code)
109 write_lock_bh(&call->state_lock);
111 if (call->state <= RXRPC_CALL_COMPLETE) {
112 call->state = RXRPC_CALL_LOCALLY_ABORTED;
113 call->abort_code = abort_code;
114 set_bit(RXRPC_CALL_ABORT, &call->events);
115 del_timer_sync(&call->resend_timer);
116 del_timer_sync(&call->ack_timer);
117 clear_bit(RXRPC_CALL_RESEND_TIMER, &call->events);
118 clear_bit(RXRPC_CALL_ACK, &call->events);
119 clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
120 rxrpc_queue_call(call);
123 write_unlock_bh(&call->state_lock);
127 * send a message forming part of a client call through an RxRPC socket
128 * - caller holds the socket locked
129 * - the socket may be either a client socket or a server socket
131 int rxrpc_client_sendmsg(struct rxrpc_sock *rx, struct rxrpc_transport *trans,
132 struct msghdr *msg, size_t len)
134 struct rxrpc_conn_bundle *bundle;
135 enum rxrpc_command cmd;
136 struct rxrpc_call *call;
137 unsigned long user_call_ID = 0;
138 struct key *key;
139 __be16 service_id;
140 u32 abort_code = 0;
141 int ret;
143 _enter("");
145 ASSERT(trans != NULL);
147 ret = rxrpc_sendmsg_cmsg(rx, msg, &user_call_ID, &cmd, &abort_code,
148 false);
149 if (ret < 0)
150 return ret;
152 bundle = NULL;
153 if (trans) {
154 service_id = rx->service_id;
155 if (msg->msg_name) {
156 DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx,
157 msg->msg_name);
158 service_id = htons(srx->srx_service);
160 key = rx->key;
161 if (key && !rx->key->payload.data[0])
162 key = NULL;
163 bundle = rxrpc_get_bundle(rx, trans, key, service_id,
164 GFP_KERNEL);
165 if (IS_ERR(bundle))
166 return PTR_ERR(bundle);
169 call = rxrpc_get_client_call(rx, trans, bundle, user_call_ID,
170 abort_code == 0, GFP_KERNEL);
171 if (trans)
172 rxrpc_put_bundle(trans, bundle);
173 if (IS_ERR(call)) {
174 _leave(" = %ld", PTR_ERR(call));
175 return PTR_ERR(call);
178 _debug("CALL %d USR %lx ST %d on CONN %p",
179 call->debug_id, call->user_call_ID, call->state, call->conn);
181 if (call->state >= RXRPC_CALL_COMPLETE) {
182 /* it's too late for this call */
183 ret = -ESHUTDOWN;
184 } else if (cmd == RXRPC_CMD_SEND_ABORT) {
185 rxrpc_send_abort(call, abort_code);
186 } else if (cmd != RXRPC_CMD_SEND_DATA) {
187 ret = -EINVAL;
188 } else if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
189 /* request phase complete for this client call */
190 ret = -EPROTO;
191 } else {
192 ret = rxrpc_send_data(rx, call, msg, len);
195 rxrpc_put_call(call);
196 _leave(" = %d", ret);
197 return ret;
201 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
202 * @call: The call to send data through
203 * @msg: The data to send
204 * @len: The amount of data to send
206 * Allow a kernel service to send data on a call. The call must be in an state
207 * appropriate to sending data. No control data should be supplied in @msg,
208 * nor should an address be supplied. MSG_MORE should be flagged if there's
209 * more data to come, otherwise this data will end the transmission phase.
211 int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg,
212 size_t len)
214 int ret;
216 _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
218 ASSERTCMP(msg->msg_name, ==, NULL);
219 ASSERTCMP(msg->msg_control, ==, NULL);
221 lock_sock(&call->socket->sk);
223 _debug("CALL %d USR %lx ST %d on CONN %p",
224 call->debug_id, call->user_call_ID, call->state, call->conn);
226 if (call->state >= RXRPC_CALL_COMPLETE) {
227 ret = -ESHUTDOWN; /* it's too late for this call */
228 } else if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
229 call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
230 call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
231 ret = -EPROTO; /* request phase complete for this client call */
232 } else {
233 ret = rxrpc_send_data(call->socket, call, msg, len);
236 release_sock(&call->socket->sk);
237 _leave(" = %d", ret);
238 return ret;
241 EXPORT_SYMBOL(rxrpc_kernel_send_data);
244 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
245 * @call: The call to be aborted
246 * @abort_code: The abort code to stick into the ABORT packet
248 * Allow a kernel service to abort a call, if it's still in an abortable state.
250 void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code)
252 _enter("{%d},%d", call->debug_id, abort_code);
254 lock_sock(&call->socket->sk);
256 _debug("CALL %d USR %lx ST %d on CONN %p",
257 call->debug_id, call->user_call_ID, call->state, call->conn);
259 if (call->state < RXRPC_CALL_COMPLETE)
260 rxrpc_send_abort(call, abort_code);
262 release_sock(&call->socket->sk);
263 _leave("");
266 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
269 * send a message through a server socket
270 * - caller holds the socket locked
272 int rxrpc_server_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
274 enum rxrpc_command cmd;
275 struct rxrpc_call *call;
276 unsigned long user_call_ID = 0;
277 u32 abort_code = 0;
278 int ret;
280 _enter("");
282 ret = rxrpc_sendmsg_cmsg(rx, msg, &user_call_ID, &cmd, &abort_code,
283 true);
284 if (ret < 0)
285 return ret;
287 if (cmd == RXRPC_CMD_ACCEPT) {
288 call = rxrpc_accept_call(rx, user_call_ID);
289 if (IS_ERR(call))
290 return PTR_ERR(call);
291 rxrpc_put_call(call);
292 return 0;
295 call = rxrpc_find_server_call(rx, user_call_ID);
296 if (!call)
297 return -EBADSLT;
298 if (call->state >= RXRPC_CALL_COMPLETE) {
299 ret = -ESHUTDOWN;
300 goto out;
303 switch (cmd) {
304 case RXRPC_CMD_SEND_DATA:
305 if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
306 call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
307 call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
308 /* Tx phase not yet begun for this call */
309 ret = -EPROTO;
310 break;
313 ret = rxrpc_send_data(rx, call, msg, len);
314 break;
316 case RXRPC_CMD_SEND_ABORT:
317 rxrpc_send_abort(call, abort_code);
318 break;
319 default:
320 BUG();
323 out:
324 rxrpc_put_call(call);
325 _leave(" = %d", ret);
326 return ret;
330 * send a packet through the transport endpoint
332 int rxrpc_send_packet(struct rxrpc_transport *trans, struct sk_buff *skb)
334 struct kvec iov[1];
335 struct msghdr msg;
336 int ret, opt;
338 _enter(",{%d}", skb->len);
340 iov[0].iov_base = skb->head;
341 iov[0].iov_len = skb->len;
343 msg.msg_name = &trans->peer->srx.transport.sin;
344 msg.msg_namelen = sizeof(trans->peer->srx.transport.sin);
345 msg.msg_control = NULL;
346 msg.msg_controllen = 0;
347 msg.msg_flags = 0;
349 /* send the packet with the don't fragment bit set if we currently
350 * think it's small enough */
351 if (skb->len - sizeof(struct rxrpc_header) < trans->peer->maxdata) {
352 down_read(&trans->local->defrag_sem);
353 /* send the packet by UDP
354 * - returns -EMSGSIZE if UDP would have to fragment the packet
355 * to go out of the interface
356 * - in which case, we'll have processed the ICMP error
357 * message and update the peer record
359 ret = kernel_sendmsg(trans->local->socket, &msg, iov, 1,
360 iov[0].iov_len);
362 up_read(&trans->local->defrag_sem);
363 if (ret == -EMSGSIZE)
364 goto send_fragmentable;
366 _leave(" = %d [%u]", ret, trans->peer->maxdata);
367 return ret;
370 send_fragmentable:
371 /* attempt to send this message with fragmentation enabled */
372 _debug("send fragment");
374 down_write(&trans->local->defrag_sem);
375 opt = IP_PMTUDISC_DONT;
376 ret = kernel_setsockopt(trans->local->socket, SOL_IP, IP_MTU_DISCOVER,
377 (char *) &opt, sizeof(opt));
378 if (ret == 0) {
379 ret = kernel_sendmsg(trans->local->socket, &msg, iov, 1,
380 iov[0].iov_len);
382 opt = IP_PMTUDISC_DO;
383 kernel_setsockopt(trans->local->socket, SOL_IP,
384 IP_MTU_DISCOVER, (char *) &opt, sizeof(opt));
387 up_write(&trans->local->defrag_sem);
388 _leave(" = %d [frag %u]", ret, trans->peer->maxdata);
389 return ret;
393 * wait for space to appear in the transmit/ACK window
394 * - caller holds the socket locked
396 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
397 struct rxrpc_call *call,
398 long *timeo)
400 DECLARE_WAITQUEUE(myself, current);
401 int ret;
403 _enter(",{%d},%ld",
404 CIRC_SPACE(call->acks_head, call->acks_tail, call->acks_winsz),
405 *timeo);
407 add_wait_queue(&call->tx_waitq, &myself);
409 for (;;) {
410 set_current_state(TASK_INTERRUPTIBLE);
411 ret = 0;
412 if (CIRC_SPACE(call->acks_head, call->acks_tail,
413 call->acks_winsz) > 0)
414 break;
415 if (signal_pending(current)) {
416 ret = sock_intr_errno(*timeo);
417 break;
420 release_sock(&rx->sk);
421 *timeo = schedule_timeout(*timeo);
422 lock_sock(&rx->sk);
425 remove_wait_queue(&call->tx_waitq, &myself);
426 set_current_state(TASK_RUNNING);
427 _leave(" = %d", ret);
428 return ret;
432 * attempt to schedule an instant Tx resend
434 static inline void rxrpc_instant_resend(struct rxrpc_call *call)
436 read_lock_bh(&call->state_lock);
437 if (try_to_del_timer_sync(&call->resend_timer) >= 0) {
438 clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
439 if (call->state < RXRPC_CALL_COMPLETE &&
440 !test_and_set_bit(RXRPC_CALL_RESEND_TIMER, &call->events))
441 rxrpc_queue_call(call);
443 read_unlock_bh(&call->state_lock);
447 * queue a packet for transmission, set the resend timer and attempt
448 * to send the packet immediately
450 static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
451 bool last)
453 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
454 int ret;
456 _net("queue skb %p [%d]", skb, call->acks_head);
458 ASSERT(call->acks_window != NULL);
459 call->acks_window[call->acks_head] = (unsigned long) skb;
460 smp_wmb();
461 call->acks_head = (call->acks_head + 1) & (call->acks_winsz - 1);
463 if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
464 _debug("________awaiting reply/ACK__________");
465 write_lock_bh(&call->state_lock);
466 switch (call->state) {
467 case RXRPC_CALL_CLIENT_SEND_REQUEST:
468 call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
469 break;
470 case RXRPC_CALL_SERVER_ACK_REQUEST:
471 call->state = RXRPC_CALL_SERVER_SEND_REPLY;
472 if (!last)
473 break;
474 case RXRPC_CALL_SERVER_SEND_REPLY:
475 call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
476 break;
477 default:
478 break;
480 write_unlock_bh(&call->state_lock);
483 _proto("Tx DATA %%%u { #%u }",
484 ntohl(sp->hdr.serial), ntohl(sp->hdr.seq));
486 sp->need_resend = false;
487 sp->resend_at = jiffies + rxrpc_resend_timeout;
488 if (!test_and_set_bit(RXRPC_CALL_RUN_RTIMER, &call->flags)) {
489 _debug("run timer");
490 call->resend_timer.expires = sp->resend_at;
491 add_timer(&call->resend_timer);
494 /* attempt to cancel the rx-ACK timer, deferring reply transmission if
495 * we're ACK'ing the request phase of an incoming call */
496 ret = -EAGAIN;
497 if (try_to_del_timer_sync(&call->ack_timer) >= 0) {
498 /* the packet may be freed by rxrpc_process_call() before this
499 * returns */
500 ret = rxrpc_send_packet(call->conn->trans, skb);
501 _net("sent skb %p", skb);
502 } else {
503 _debug("failed to delete ACK timer");
506 if (ret < 0) {
507 _debug("need instant resend %d", ret);
508 sp->need_resend = true;
509 rxrpc_instant_resend(call);
512 _leave("");
516 * send data through a socket
517 * - must be called in process context
518 * - caller holds the socket locked
520 static int rxrpc_send_data(struct rxrpc_sock *rx,
521 struct rxrpc_call *call,
522 struct msghdr *msg, size_t len)
524 struct rxrpc_skb_priv *sp;
525 struct sk_buff *skb;
526 struct sock *sk = &rx->sk;
527 long timeo;
528 bool more;
529 int ret, copied;
531 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
533 /* this should be in poll */
534 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
536 if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
537 return -EPIPE;
539 more = msg->msg_flags & MSG_MORE;
541 skb = call->tx_pending;
542 call->tx_pending = NULL;
544 copied = 0;
545 do {
546 if (!skb) {
547 size_t size, chunk, max, space;
549 _debug("alloc");
551 if (CIRC_SPACE(call->acks_head, call->acks_tail,
552 call->acks_winsz) <= 0) {
553 ret = -EAGAIN;
554 if (msg->msg_flags & MSG_DONTWAIT)
555 goto maybe_error;
556 ret = rxrpc_wait_for_tx_window(rx, call,
557 &timeo);
558 if (ret < 0)
559 goto maybe_error;
562 max = call->conn->trans->peer->maxdata;
563 max -= call->conn->security_size;
564 max &= ~(call->conn->size_align - 1UL);
566 chunk = max;
567 if (chunk > msg_data_left(msg) && !more)
568 chunk = msg_data_left(msg);
570 space = chunk + call->conn->size_align;
571 space &= ~(call->conn->size_align - 1UL);
573 size = space + call->conn->header_size;
575 _debug("SIZE: %zu/%zu/%zu", chunk, space, size);
577 /* create a buffer that we can retain until it's ACK'd */
578 skb = sock_alloc_send_skb(
579 sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
580 if (!skb)
581 goto maybe_error;
583 rxrpc_new_skb(skb);
585 _debug("ALLOC SEND %p", skb);
587 ASSERTCMP(skb->mark, ==, 0);
589 _debug("HS: %u", call->conn->header_size);
590 skb_reserve(skb, call->conn->header_size);
591 skb->len += call->conn->header_size;
593 sp = rxrpc_skb(skb);
594 sp->remain = chunk;
595 if (sp->remain > skb_tailroom(skb))
596 sp->remain = skb_tailroom(skb);
598 _net("skb: hr %d, tr %d, hl %d, rm %d",
599 skb_headroom(skb),
600 skb_tailroom(skb),
601 skb_headlen(skb),
602 sp->remain);
604 skb->ip_summed = CHECKSUM_UNNECESSARY;
607 _debug("append");
608 sp = rxrpc_skb(skb);
610 /* append next segment of data to the current buffer */
611 if (msg_data_left(msg) > 0) {
612 int copy = skb_tailroom(skb);
613 ASSERTCMP(copy, >, 0);
614 if (copy > msg_data_left(msg))
615 copy = msg_data_left(msg);
616 if (copy > sp->remain)
617 copy = sp->remain;
619 _debug("add");
620 ret = skb_add_data(skb, &msg->msg_iter, copy);
621 _debug("added");
622 if (ret < 0)
623 goto efault;
624 sp->remain -= copy;
625 skb->mark += copy;
626 copied += copy;
629 /* check for the far side aborting the call or a network error
630 * occurring */
631 if (call->state > RXRPC_CALL_COMPLETE)
632 goto call_aborted;
634 /* add the packet to the send queue if it's now full */
635 if (sp->remain <= 0 ||
636 (msg_data_left(msg) == 0 && !more)) {
637 struct rxrpc_connection *conn = call->conn;
638 uint32_t seq;
639 size_t pad;
641 /* pad out if we're using security */
642 if (conn->security) {
643 pad = conn->security_size + skb->mark;
644 pad = conn->size_align - pad;
645 pad &= conn->size_align - 1;
646 _debug("pad %zu", pad);
647 if (pad)
648 memset(skb_put(skb, pad), 0, pad);
651 seq = atomic_inc_return(&call->sequence);
653 sp->hdr.epoch = conn->epoch;
654 sp->hdr.cid = call->cid;
655 sp->hdr.callNumber = call->call_id;
656 sp->hdr.seq = htonl(seq);
657 sp->hdr.serial =
658 htonl(atomic_inc_return(&conn->serial));
659 sp->hdr.type = RXRPC_PACKET_TYPE_DATA;
660 sp->hdr.userStatus = 0;
661 sp->hdr.securityIndex = conn->security_ix;
662 sp->hdr._rsvd = 0;
663 sp->hdr.serviceId = conn->service_id;
665 sp->hdr.flags = conn->out_clientflag;
666 if (msg_data_left(msg) == 0 && !more)
667 sp->hdr.flags |= RXRPC_LAST_PACKET;
668 else if (CIRC_SPACE(call->acks_head, call->acks_tail,
669 call->acks_winsz) > 1)
670 sp->hdr.flags |= RXRPC_MORE_PACKETS;
671 if (more && seq & 1)
672 sp->hdr.flags |= RXRPC_REQUEST_ACK;
674 ret = rxrpc_secure_packet(
675 call, skb, skb->mark,
676 skb->head + sizeof(struct rxrpc_header));
677 if (ret < 0)
678 goto out;
680 memcpy(skb->head, &sp->hdr,
681 sizeof(struct rxrpc_header));
682 rxrpc_queue_packet(call, skb, !msg_data_left(msg) && !more);
683 skb = NULL;
685 } while (msg_data_left(msg) > 0);
687 success:
688 ret = copied;
689 out:
690 call->tx_pending = skb;
691 _leave(" = %d", ret);
692 return ret;
694 call_aborted:
695 rxrpc_free_skb(skb);
696 if (call->state == RXRPC_CALL_NETWORK_ERROR)
697 ret = call->conn->trans->peer->net_error;
698 else
699 ret = -ECONNABORTED;
700 _leave(" = %d", ret);
701 return ret;
703 maybe_error:
704 if (copied)
705 goto success;
706 goto out;
708 efault:
709 ret = -EFAULT;
710 goto out;