1 /* connection.c: Rx connection routines
3 * Copyright (C) 2002 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/sched.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <rxrpc/rxrpc.h>
16 #include <rxrpc/transport.h>
17 #include <rxrpc/peer.h>
18 #include <rxrpc/connection.h>
19 #include <rxrpc/call.h>
20 #include <rxrpc/message.h>
21 #include <linux/udp.h>
24 #include <asm/uaccess.h>
27 __RXACCT_DECL(atomic_t rxrpc_connection_count);
29 LIST_HEAD(rxrpc_conns);
30 DECLARE_RWSEM(rxrpc_conns_sem);
31 unsigned long rxrpc_conn_timeout = 60 * 60;
33 static void rxrpc_conn_do_timeout(struct rxrpc_connection *conn);
35 static void __rxrpc_conn_timeout(rxrpc_timer_t *timer)
37 struct rxrpc_connection *conn =
38 list_entry(timer, struct rxrpc_connection, timeout);
40 _debug("Rx CONN TIMEOUT [%p{u=%d}]", conn, atomic_read(&conn->usage));
42 rxrpc_conn_do_timeout(conn);
45 static const struct rxrpc_timer_ops rxrpc_conn_timer_ops = {
46 .timed_out = __rxrpc_conn_timeout,
49 /*****************************************************************************/
51 * create a new connection record
53 static inline int __rxrpc_create_connection(struct rxrpc_peer *peer,
54 struct rxrpc_connection **_conn)
56 struct rxrpc_connection *conn;
60 /* allocate and initialise a connection record */
61 conn = kmalloc(sizeof(struct rxrpc_connection), GFP_KERNEL);
67 memset(conn, 0, sizeof(struct rxrpc_connection));
68 atomic_set(&conn->usage, 1);
70 INIT_LIST_HEAD(&conn->link);
71 INIT_LIST_HEAD(&conn->id_link);
72 init_waitqueue_head(&conn->chanwait);
73 spin_lock_init(&conn->lock);
74 rxrpc_timer_init(&conn->timeout, &rxrpc_conn_timer_ops);
76 do_gettimeofday(&conn->atime);
77 conn->mtu_size = 1024;
79 conn->trans = peer->trans;
81 __RXACCT(atomic_inc(&rxrpc_connection_count));
83 _leave(" = 0 (%p)", conn);
86 } /* end __rxrpc_create_connection() */
88 /*****************************************************************************/
90 * create a new connection record for outgoing connections
92 int rxrpc_create_connection(struct rxrpc_transport *trans,
97 struct rxrpc_connection **_conn)
99 struct rxrpc_connection *candidate, *conn;
100 struct rxrpc_peer *peer;
101 struct list_head *_p;
105 _enter("%p{%hu},%u,%hu", trans, trans->port, ntohs(port), service_id);
107 /* get a peer record */
108 ret = rxrpc_peer_lookup(trans, addr, &peer);
110 _leave(" = %d", ret);
114 /* allocate and initialise a connection record */
115 ret = __rxrpc_create_connection(peer, &candidate);
117 rxrpc_put_peer(peer);
118 _leave(" = %d", ret);
122 /* fill in the specific bits */
123 candidate->addr.sin_family = AF_INET;
124 candidate->addr.sin_port = port;
125 candidate->addr.sin_addr.s_addr = addr;
127 candidate->in_epoch = rxrpc_epoch;
128 candidate->out_epoch = rxrpc_epoch;
129 candidate->in_clientflag = 0;
130 candidate->out_clientflag = RXRPC_CLIENT_INITIATED;
131 candidate->service_id = htons(service_id);
133 /* invent a unique connection ID */
134 write_lock(&peer->conn_idlock);
137 connid = htonl(peer->conn_idcounter & RXRPC_CIDMASK);
138 peer->conn_idcounter += RXRPC_MAXCALLS;
140 list_for_each(_p, &peer->conn_idlist) {
141 conn = list_entry(_p, struct rxrpc_connection, id_link);
142 if (connid == conn->conn_id)
144 if (connid > conn->conn_id)
148 _debug("selected candidate conn ID %x.%u",
149 ntohl(peer->addr.s_addr), ntohl(connid));
151 candidate->conn_id = connid;
152 list_add_tail(&candidate->id_link, _p);
154 write_unlock(&peer->conn_idlock);
157 candidate->peer = peer;
159 write_lock(&peer->conn_lock);
161 /* search the peer's transport graveyard list */
162 spin_lock(&peer->conn_gylock);
163 list_for_each(_p, &peer->conn_graveyard) {
164 conn = list_entry(_p, struct rxrpc_connection, link);
165 if (conn->addr.sin_port == candidate->addr.sin_port &&
166 conn->security_ix == candidate->security_ix &&
167 conn->service_id == candidate->service_id &&
168 conn->in_clientflag == 0)
169 goto found_in_graveyard;
171 spin_unlock(&peer->conn_gylock);
173 /* pick the new candidate */
174 _debug("created connection: {%08x} [out]", ntohl(candidate->conn_id));
175 atomic_inc(&peer->conn_count);
180 list_add_tail(&conn->link, &peer->conn_active);
181 write_unlock(&peer->conn_lock);
184 write_lock(&peer->conn_idlock);
185 list_del(&candidate->id_link);
186 write_unlock(&peer->conn_idlock);
188 __RXACCT(atomic_dec(&rxrpc_connection_count));
192 down_write(&rxrpc_conns_sem);
193 list_add_tail(&conn->proc_link, &rxrpc_conns);
194 up_write(&rxrpc_conns_sem);
198 _leave(" = 0 (%p)", conn);
202 /* handle resurrecting a connection from the graveyard */
204 _debug("resurrecting connection: {%08x} [out]", ntohl(conn->conn_id));
205 rxrpc_get_connection(conn);
206 rxrpc_krxtimod_del_timer(&conn->timeout);
207 list_del_init(&conn->link);
208 spin_unlock(&peer->conn_gylock);
210 } /* end rxrpc_create_connection() */
212 /*****************************************************************************/
214 * lookup the connection for an incoming packet
215 * - create a new connection record for unrecorded incoming connections
217 int rxrpc_connection_lookup(struct rxrpc_peer *peer,
218 struct rxrpc_message *msg,
219 struct rxrpc_connection **_conn)
221 struct rxrpc_connection *conn, *candidate = NULL;
222 struct list_head *_p;
223 struct sk_buff *pkt = msg->pkt;
225 __be32 x_epoch, x_connid;
226 __be16 x_port, x_servid;
230 _enter("%p{{%hu}},%u,%hu",
233 ntohs(pkt->h.uh->source),
234 ntohs(msg->hdr.serviceId));
236 x_port = pkt->h.uh->source;
237 x_epoch = msg->hdr.epoch;
238 x_clflag = msg->hdr.flags & RXRPC_CLIENT_INITIATED;
239 x_connid = htonl(ntohl(msg->hdr.cid) & RXRPC_CIDMASK);
240 x_servid = msg->hdr.serviceId;
241 x_secix = msg->hdr.securityIndex;
243 /* [common case] search the transport's active list first */
244 read_lock(&peer->conn_lock);
245 list_for_each(_p, &peer->conn_active) {
246 conn = list_entry(_p, struct rxrpc_connection, link);
247 if (conn->addr.sin_port == x_port &&
248 conn->in_epoch == x_epoch &&
249 conn->conn_id == x_connid &&
250 conn->security_ix == x_secix &&
251 conn->service_id == x_servid &&
252 conn->in_clientflag == x_clflag)
255 read_unlock(&peer->conn_lock);
257 /* [uncommon case] not active
258 * - create a candidate for a new record if an inbound connection
259 * - only examine the graveyard for an outbound connection
262 ret = __rxrpc_create_connection(peer, &candidate);
264 _leave(" = %d", ret);
268 /* fill in the specifics */
269 candidate->addr.sin_family = AF_INET;
270 candidate->addr.sin_port = x_port;
271 candidate->addr.sin_addr.s_addr = pkt->nh.iph->saddr;
272 candidate->in_epoch = x_epoch;
273 candidate->out_epoch = x_epoch;
274 candidate->in_clientflag = RXRPC_CLIENT_INITIATED;
275 candidate->out_clientflag = 0;
276 candidate->conn_id = x_connid;
277 candidate->service_id = x_servid;
278 candidate->security_ix = x_secix;
281 /* search the active list again, just in case it appeared whilst we
283 write_lock(&peer->conn_lock);
284 list_for_each(_p, &peer->conn_active) {
285 conn = list_entry(_p, struct rxrpc_connection, link);
286 if (conn->addr.sin_port == x_port &&
287 conn->in_epoch == x_epoch &&
288 conn->conn_id == x_connid &&
289 conn->security_ix == x_secix &&
290 conn->service_id == x_servid &&
291 conn->in_clientflag == x_clflag)
292 goto found_active_second_chance;
295 /* search the transport's graveyard list */
296 spin_lock(&peer->conn_gylock);
297 list_for_each(_p, &peer->conn_graveyard) {
298 conn = list_entry(_p, struct rxrpc_connection, link);
299 if (conn->addr.sin_port == x_port &&
300 conn->in_epoch == x_epoch &&
301 conn->conn_id == x_connid &&
302 conn->security_ix == x_secix &&
303 conn->service_id == x_servid &&
304 conn->in_clientflag == x_clflag)
305 goto found_in_graveyard;
307 spin_unlock(&peer->conn_gylock);
309 /* outbound connections aren't created here */
311 write_unlock(&peer->conn_lock);
312 _leave(" = -ENOENT");
316 /* we can now add the new candidate to the list */
317 _debug("created connection: {%08x} [in]", ntohl(candidate->conn_id));
318 rxrpc_get_peer(peer);
321 atomic_inc(&peer->conn_count);
325 list_add_tail(&conn->link, &peer->conn_active);
328 write_unlock(&peer->conn_lock);
331 write_lock(&peer->conn_idlock);
332 list_del(&candidate->id_link);
333 write_unlock(&peer->conn_idlock);
335 __RXACCT(atomic_dec(&rxrpc_connection_count));
340 down_write(&rxrpc_conns_sem);
341 list_add_tail(&conn->proc_link, &rxrpc_conns);
342 up_write(&rxrpc_conns_sem);
347 _leave(" = 0 (%p)", conn);
350 /* handle the connection being found in the active list straight off */
352 rxrpc_get_connection(conn);
353 read_unlock(&peer->conn_lock);
356 /* handle resurrecting a connection from the graveyard */
358 _debug("resurrecting connection: {%08x} [in]", ntohl(conn->conn_id));
359 rxrpc_get_peer(peer);
360 rxrpc_get_connection(conn);
361 rxrpc_krxtimod_del_timer(&conn->timeout);
362 list_del_init(&conn->link);
363 spin_unlock(&peer->conn_gylock);
366 /* handle finding the connection on the second time through the active
368 found_active_second_chance:
369 rxrpc_get_connection(conn);
372 } /* end rxrpc_connection_lookup() */
374 /*****************************************************************************/
376 * finish using a connection record
377 * - it will be transferred to the peer's connection graveyard when refcount
380 void rxrpc_put_connection(struct rxrpc_connection *conn)
382 struct rxrpc_peer *peer;
387 _enter("%p{u=%d p=%hu}",
388 conn, atomic_read(&conn->usage), ntohs(conn->addr.sin_port));
391 spin_lock(&peer->conn_gylock);
394 if (atomic_read(&conn->usage) <= 0)
397 if (likely(!atomic_dec_and_test(&conn->usage))) {
398 spin_unlock(&peer->conn_gylock);
403 /* move to graveyard queue */
404 _debug("burying connection: {%08x}", ntohl(conn->conn_id));
405 list_del(&conn->link);
406 list_add_tail(&conn->link, &peer->conn_graveyard);
408 rxrpc_krxtimod_add_timer(&conn->timeout, rxrpc_conn_timeout * HZ);
410 spin_unlock(&peer->conn_gylock);
412 rxrpc_put_peer(conn->peer);
415 } /* end rxrpc_put_connection() */
417 /*****************************************************************************/
419 * free a connection record
421 static void rxrpc_conn_do_timeout(struct rxrpc_connection *conn)
423 struct rxrpc_peer *peer;
425 _enter("%p{u=%d p=%hu}",
426 conn, atomic_read(&conn->usage), ntohs(conn->addr.sin_port));
430 if (atomic_read(&conn->usage) < 0)
433 /* remove from graveyard if still dead */
434 spin_lock(&peer->conn_gylock);
435 if (atomic_read(&conn->usage) == 0) {
436 list_del_init(&conn->link);
441 spin_unlock(&peer->conn_gylock);
445 return; /* resurrected */
448 _debug("--- Destroying Connection %p{%08x} ---",
449 conn, ntohl(conn->conn_id));
451 down_write(&rxrpc_conns_sem);
452 list_del(&conn->proc_link);
453 up_write(&rxrpc_conns_sem);
455 write_lock(&peer->conn_idlock);
456 list_del(&conn->id_link);
457 write_unlock(&peer->conn_idlock);
459 __RXACCT(atomic_dec(&rxrpc_connection_count));
462 /* if the graveyard is now empty, wake up anyone waiting for that */
463 if (atomic_dec_and_test(&peer->conn_count))
464 wake_up(&peer->conn_gy_waitq);
466 _leave(" [destroyed]");
467 } /* end rxrpc_conn_do_timeout() */
469 /*****************************************************************************/
471 * clear all connection records from a peer endpoint
473 void rxrpc_conn_clearall(struct rxrpc_peer *peer)
475 DECLARE_WAITQUEUE(myself, current);
477 struct rxrpc_connection *conn;
482 /* there shouldn't be any active conns remaining */
483 if (!list_empty(&peer->conn_active))
486 /* manually timeout all conns in the graveyard */
487 spin_lock(&peer->conn_gylock);
488 while (!list_empty(&peer->conn_graveyard)) {
489 conn = list_entry(peer->conn_graveyard.next,
490 struct rxrpc_connection, link);
491 err = rxrpc_krxtimod_del_timer(&conn->timeout);
492 spin_unlock(&peer->conn_gylock);
495 rxrpc_conn_do_timeout(conn);
497 spin_lock(&peer->conn_gylock);
499 spin_unlock(&peer->conn_gylock);
501 /* wait for the the conn graveyard to be completely cleared */
502 set_current_state(TASK_UNINTERRUPTIBLE);
503 add_wait_queue(&peer->conn_gy_waitq, &myself);
505 while (atomic_read(&peer->conn_count) != 0) {
507 set_current_state(TASK_UNINTERRUPTIBLE);
510 remove_wait_queue(&peer->conn_gy_waitq, &myself);
511 set_current_state(TASK_RUNNING);
514 } /* end rxrpc_conn_clearall() */
516 /*****************************************************************************/
518 * allocate and prepare a message for sending out through the transport
521 int rxrpc_conn_newmsg(struct rxrpc_connection *conn,
522 struct rxrpc_call *call,
527 struct rxrpc_message **_msg)
529 struct rxrpc_message *msg;
532 _enter("%p{%d},%p,%u", conn, ntohs(conn->addr.sin_port), call, type);
535 _leave(" = -EINVAL");
539 msg = kmalloc(sizeof(struct rxrpc_message), alloc_flags);
541 _leave(" = -ENOMEM");
545 memset(msg, 0, sizeof(*msg));
546 atomic_set(&msg->usage, 1);
548 INIT_LIST_HEAD(&msg->link);
550 msg->state = RXRPC_MSG_PREPARED;
552 msg->hdr.epoch = conn->out_epoch;
553 msg->hdr.cid = conn->conn_id | (call ? call->chan_ix : 0);
554 msg->hdr.callNumber = call ? call->call_id : 0;
555 msg->hdr.type = type;
556 msg->hdr.flags = conn->out_clientflag;
557 msg->hdr.securityIndex = conn->security_ix;
558 msg->hdr.serviceId = conn->service_id;
560 /* generate sequence numbers for data packets */
563 case RXRPC_PACKET_TYPE_DATA:
564 msg->seq = ++call->snd_seq_count;
565 msg->hdr.seq = htonl(msg->seq);
567 case RXRPC_PACKET_TYPE_ACK:
568 /* ACK sequence numbers are complicated. The following
570 * - jumbo packet ACKs should have a seq number
571 * - normal ACKs should not
578 msg->dcount = dcount + 1;
579 msg->dsize = sizeof(msg->hdr);
580 msg->data[0].iov_len = sizeof(msg->hdr);
581 msg->data[0].iov_base = &msg->hdr;
583 for (loop=0; loop < dcount; loop++) {
584 msg->dsize += diov[loop].iov_len;
585 msg->data[loop+1].iov_len = diov[loop].iov_len;
586 msg->data[loop+1].iov_base = diov[loop].iov_base;
589 __RXACCT(atomic_inc(&rxrpc_message_count));
591 _leave(" = 0 (%p) #%d", msg, atomic_read(&rxrpc_message_count));
593 } /* end rxrpc_conn_newmsg() */
595 /*****************************************************************************/
599 void __rxrpc_put_message(struct rxrpc_message *msg)
603 _enter("%p #%d", msg, atomic_read(&rxrpc_message_count));
607 rxrpc_put_connection(msg->conn);
609 for (loop = 0; loop < 8; loop++)
610 if (test_bit(loop, &msg->dfree))
611 kfree(msg->data[loop].iov_base);
613 __RXACCT(atomic_dec(&rxrpc_message_count));
617 } /* end __rxrpc_put_message() */
619 /*****************************************************************************/
621 * send a message out through the transport endpoint
623 int rxrpc_conn_sendmsg(struct rxrpc_connection *conn,
624 struct rxrpc_message *msg)
626 struct msghdr msghdr;
629 _enter("%p{%d}", conn, ntohs(conn->addr.sin_port));
631 /* fill in some fields in the header */
632 spin_lock(&conn->lock);
633 msg->hdr.serial = htonl(++conn->serial_counter);
635 spin_unlock(&conn->lock);
637 /* set up the message to be transmitted */
638 msghdr.msg_name = &conn->addr;
639 msghdr.msg_namelen = sizeof(conn->addr);
640 msghdr.msg_control = NULL;
641 msghdr.msg_controllen = 0;
642 msghdr.msg_flags = MSG_CONFIRM | MSG_DONTWAIT;
644 _net("Sending message type %d of %Zd bytes to %08x:%d",
647 ntohl(conn->addr.sin_addr.s_addr),
648 ntohs(conn->addr.sin_port));
650 /* send the message */
651 ret = kernel_sendmsg(conn->trans->socket, &msghdr,
652 msg->data, msg->dcount, msg->dsize);
654 msg->state = RXRPC_MSG_ERROR;
656 msg->state = RXRPC_MSG_SENT;
659 spin_lock(&conn->lock);
660 do_gettimeofday(&conn->atime);
661 msg->stamp = conn->atime;
662 spin_unlock(&conn->lock);
665 _leave(" = %d", ret);
668 } /* end rxrpc_conn_sendmsg() */
670 /*****************************************************************************/
672 * deal with a subsequent call packet
674 int rxrpc_conn_receive_call_packet(struct rxrpc_connection *conn,
675 struct rxrpc_call *call,
676 struct rxrpc_message *msg)
678 struct rxrpc_message *pmsg;
679 struct dst_entry *dst;
680 struct list_head *_p;
684 _enter("%p,%p,%p", conn, call, msg);
687 cix = ntohl(msg->hdr.cid) & RXRPC_CHANNELMASK;
689 spin_lock(&conn->lock);
690 call = conn->channels[cix];
692 if (!call || call->call_id != msg->hdr.callNumber) {
693 spin_unlock(&conn->lock);
694 rxrpc_trans_immediate_abort(conn->trans, msg, -ENOENT);
698 rxrpc_get_call(call);
699 spin_unlock(&conn->lock);
703 rxrpc_get_call(call);
706 _proto("Received packet %%%u [%u] on call %hu:%u:%u",
707 ntohl(msg->hdr.serial),
709 ntohs(msg->hdr.serviceId),
710 ntohl(conn->conn_id),
711 ntohl(call->call_id));
713 call->pkt_rcv_count++;
718 dst->dev->mtu - dst->dev->hard_header_len;
720 /* queue on the call in seq order */
721 rxrpc_get_message(msg);
724 spin_lock(&call->lock);
725 list_for_each(_p, &call->rcv_receiveq) {
726 pmsg = list_entry(_p, struct rxrpc_message, link);
730 list_add_tail(&msg->link, _p);
732 /* reset the activity timeout */
733 call->flags |= RXRPC_CALL_RCV_PKT;
734 mod_timer(&call->rcv_timeout,jiffies + rxrpc_call_rcv_timeout * HZ);
736 spin_unlock(&call->lock);
738 rxrpc_krxiod_queue_call(call);
740 rxrpc_put_call(call);
742 _leave(" = %d", ret);
744 } /* end rxrpc_conn_receive_call_packet() */
746 /*****************************************************************************/
748 * handle an ICMP error being applied to a connection
750 void rxrpc_conn_handle_error(struct rxrpc_connection *conn,
751 int local, int errno)
753 struct rxrpc_call *calls[4];
756 _enter("%p{%d},%d", conn, ntohs(conn->addr.sin_port), errno);
758 /* get a ref to all my calls in one go */
759 memset(calls, 0, sizeof(calls));
760 spin_lock(&conn->lock);
762 for (loop = 3; loop >= 0; loop--) {
763 if (conn->channels[loop]) {
764 calls[loop] = conn->channels[loop];
765 rxrpc_get_call(calls[loop]);
769 spin_unlock(&conn->lock);
771 /* now kick them all */
772 for (loop = 3; loop >= 0; loop--) {
774 rxrpc_call_handle_error(calls[loop], local, errno);
775 rxrpc_put_call(calls[loop]);
780 } /* end rxrpc_conn_handle_error() */