Linux 5.7.7
[linux/fpc-iii.git] / net / rxrpc / conn_object.c
blob19e141eeed17dca26e90450cc12dc8c3728b9798
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* RxRPC virtual connection handler, common bits.
4 * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/net.h>
13 #include <linux/skbuff.h>
14 #include "ar-internal.h"
17 * Time till a connection expires after last use (in seconds).
19 unsigned int __read_mostly rxrpc_connection_expiry = 10 * 60;
20 unsigned int __read_mostly rxrpc_closed_conn_expiry = 10;
22 static void rxrpc_destroy_connection(struct rcu_head *);
24 static void rxrpc_connection_timer(struct timer_list *timer)
26 struct rxrpc_connection *conn =
27 container_of(timer, struct rxrpc_connection, timer);
29 rxrpc_queue_conn(conn);
33 * allocate a new connection
35 struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp)
37 struct rxrpc_connection *conn;
39 _enter("");
41 conn = kzalloc(sizeof(struct rxrpc_connection), gfp);
42 if (conn) {
43 INIT_LIST_HEAD(&conn->cache_link);
44 spin_lock_init(&conn->channel_lock);
45 INIT_LIST_HEAD(&conn->waiting_calls);
46 timer_setup(&conn->timer, &rxrpc_connection_timer, 0);
47 INIT_WORK(&conn->processor, &rxrpc_process_connection);
48 INIT_LIST_HEAD(&conn->proc_link);
49 INIT_LIST_HEAD(&conn->link);
50 skb_queue_head_init(&conn->rx_queue);
51 conn->security = &rxrpc_no_security;
52 spin_lock_init(&conn->state_lock);
53 conn->debug_id = atomic_inc_return(&rxrpc_debug_id);
54 conn->size_align = 4;
55 conn->idle_timestamp = jiffies;
58 _leave(" = %p{%d}", conn, conn ? conn->debug_id : 0);
59 return conn;
63 * Look up a connection in the cache by protocol parameters.
65 * If successful, a pointer to the connection is returned, but no ref is taken.
66 * NULL is returned if there is no match.
68 * When searching for a service call, if we find a peer but no connection, we
69 * return that through *_peer in case we need to create a new service call.
71 * The caller must be holding the RCU read lock.
73 struct rxrpc_connection *rxrpc_find_connection_rcu(struct rxrpc_local *local,
74 struct sk_buff *skb,
75 struct rxrpc_peer **_peer)
77 struct rxrpc_connection *conn;
78 struct rxrpc_conn_proto k;
79 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
80 struct sockaddr_rxrpc srx;
81 struct rxrpc_peer *peer;
83 _enter(",%x", sp->hdr.cid & RXRPC_CIDMASK);
85 if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
86 goto not_found;
88 if (srx.transport.family != local->srx.transport.family &&
89 (srx.transport.family == AF_INET &&
90 local->srx.transport.family != AF_INET6)) {
91 pr_warn_ratelimited("AF_RXRPC: Protocol mismatch %u not %u\n",
92 srx.transport.family,
93 local->srx.transport.family);
94 goto not_found;
97 k.epoch = sp->hdr.epoch;
98 k.cid = sp->hdr.cid & RXRPC_CIDMASK;
100 if (rxrpc_to_server(sp)) {
101 /* We need to look up service connections by the full protocol
102 * parameter set. We look up the peer first as an intermediate
103 * step and then the connection from the peer's tree.
105 peer = rxrpc_lookup_peer_rcu(local, &srx);
106 if (!peer)
107 goto not_found;
108 *_peer = peer;
109 conn = rxrpc_find_service_conn_rcu(peer, skb);
110 if (!conn || atomic_read(&conn->usage) == 0)
111 goto not_found;
112 _leave(" = %p", conn);
113 return conn;
114 } else {
115 /* Look up client connections by connection ID alone as their
116 * IDs are unique for this machine.
118 conn = idr_find(&rxrpc_client_conn_ids,
119 sp->hdr.cid >> RXRPC_CIDSHIFT);
120 if (!conn || atomic_read(&conn->usage) == 0) {
121 _debug("no conn");
122 goto not_found;
125 if (conn->proto.epoch != k.epoch ||
126 conn->params.local != local)
127 goto not_found;
129 peer = conn->params.peer;
130 switch (srx.transport.family) {
131 case AF_INET:
132 if (peer->srx.transport.sin.sin_port !=
133 srx.transport.sin.sin_port ||
134 peer->srx.transport.sin.sin_addr.s_addr !=
135 srx.transport.sin.sin_addr.s_addr)
136 goto not_found;
137 break;
138 #ifdef CONFIG_AF_RXRPC_IPV6
139 case AF_INET6:
140 if (peer->srx.transport.sin6.sin6_port !=
141 srx.transport.sin6.sin6_port ||
142 memcmp(&peer->srx.transport.sin6.sin6_addr,
143 &srx.transport.sin6.sin6_addr,
144 sizeof(struct in6_addr)) != 0)
145 goto not_found;
146 break;
147 #endif
148 default:
149 BUG();
152 _leave(" = %p", conn);
153 return conn;
156 not_found:
157 _leave(" = NULL");
158 return NULL;
162 * Disconnect a call and clear any channel it occupies when that call
163 * terminates. The caller must hold the channel_lock and must release the
164 * call's ref on the connection.
166 void __rxrpc_disconnect_call(struct rxrpc_connection *conn,
167 struct rxrpc_call *call)
169 struct rxrpc_channel *chan =
170 &conn->channels[call->cid & RXRPC_CHANNELMASK];
172 _enter("%d,%x", conn->debug_id, call->cid);
174 if (rcu_access_pointer(chan->call) == call) {
175 /* Save the result of the call so that we can repeat it if necessary
176 * through the channel, whilst disposing of the actual call record.
178 trace_rxrpc_disconnect_call(call);
179 switch (call->completion) {
180 case RXRPC_CALL_SUCCEEDED:
181 chan->last_seq = call->rx_hard_ack;
182 chan->last_type = RXRPC_PACKET_TYPE_ACK;
183 break;
184 case RXRPC_CALL_LOCALLY_ABORTED:
185 chan->last_abort = call->abort_code;
186 chan->last_type = RXRPC_PACKET_TYPE_ABORT;
187 break;
188 default:
189 chan->last_abort = RX_USER_ABORT;
190 chan->last_type = RXRPC_PACKET_TYPE_ABORT;
191 break;
194 /* Sync with rxrpc_conn_retransmit(). */
195 smp_wmb();
196 chan->last_call = chan->call_id;
197 chan->call_id = chan->call_counter;
199 rcu_assign_pointer(chan->call, NULL);
202 _leave("");
206 * Disconnect a call and clear any channel it occupies when that call
207 * terminates.
209 void rxrpc_disconnect_call(struct rxrpc_call *call)
211 struct rxrpc_connection *conn = call->conn;
213 call->peer->cong_cwnd = call->cong_cwnd;
215 spin_lock_bh(&conn->params.peer->lock);
216 hlist_del_rcu(&call->error_link);
217 spin_unlock_bh(&conn->params.peer->lock);
219 if (rxrpc_is_client_call(call))
220 return rxrpc_disconnect_client_call(call);
222 spin_lock(&conn->channel_lock);
223 __rxrpc_disconnect_call(conn, call);
224 spin_unlock(&conn->channel_lock);
226 set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
227 conn->idle_timestamp = jiffies;
231 * Kill off a connection.
233 void rxrpc_kill_connection(struct rxrpc_connection *conn)
235 struct rxrpc_net *rxnet = conn->params.local->rxnet;
237 ASSERT(!rcu_access_pointer(conn->channels[0].call) &&
238 !rcu_access_pointer(conn->channels[1].call) &&
239 !rcu_access_pointer(conn->channels[2].call) &&
240 !rcu_access_pointer(conn->channels[3].call));
241 ASSERT(list_empty(&conn->cache_link));
243 write_lock(&rxnet->conn_lock);
244 list_del_init(&conn->proc_link);
245 write_unlock(&rxnet->conn_lock);
247 /* Drain the Rx queue. Note that even though we've unpublished, an
248 * incoming packet could still be being added to our Rx queue, so we
249 * will need to drain it again in the RCU cleanup handler.
251 rxrpc_purge_queue(&conn->rx_queue);
253 /* Leave final destruction to RCU. The connection processor work item
254 * must carry a ref on the connection to prevent us getting here whilst
255 * it is queued or running.
257 call_rcu(&conn->rcu, rxrpc_destroy_connection);
261 * Queue a connection's work processor, getting a ref to pass to the work
262 * queue.
264 bool rxrpc_queue_conn(struct rxrpc_connection *conn)
266 const void *here = __builtin_return_address(0);
267 int n = atomic_fetch_add_unless(&conn->usage, 1, 0);
268 if (n == 0)
269 return false;
270 if (rxrpc_queue_work(&conn->processor))
271 trace_rxrpc_conn(conn->debug_id, rxrpc_conn_queued, n + 1, here);
272 else
273 rxrpc_put_connection(conn);
274 return true;
278 * Note the re-emergence of a connection.
280 void rxrpc_see_connection(struct rxrpc_connection *conn)
282 const void *here = __builtin_return_address(0);
283 if (conn) {
284 int n = atomic_read(&conn->usage);
286 trace_rxrpc_conn(conn->debug_id, rxrpc_conn_seen, n, here);
291 * Get a ref on a connection.
293 void rxrpc_get_connection(struct rxrpc_connection *conn)
295 const void *here = __builtin_return_address(0);
296 int n = atomic_inc_return(&conn->usage);
298 trace_rxrpc_conn(conn->debug_id, rxrpc_conn_got, n, here);
302 * Try to get a ref on a connection.
304 struct rxrpc_connection *
305 rxrpc_get_connection_maybe(struct rxrpc_connection *conn)
307 const void *here = __builtin_return_address(0);
309 if (conn) {
310 int n = atomic_fetch_add_unless(&conn->usage, 1, 0);
311 if (n > 0)
312 trace_rxrpc_conn(conn->debug_id, rxrpc_conn_got, n + 1, here);
313 else
314 conn = NULL;
316 return conn;
320 * Set the service connection reap timer.
322 static void rxrpc_set_service_reap_timer(struct rxrpc_net *rxnet,
323 unsigned long reap_at)
325 if (rxnet->live)
326 timer_reduce(&rxnet->service_conn_reap_timer, reap_at);
330 * Release a service connection
332 void rxrpc_put_service_conn(struct rxrpc_connection *conn)
334 const void *here = __builtin_return_address(0);
335 unsigned int debug_id = conn->debug_id;
336 int n;
338 n = atomic_dec_return(&conn->usage);
339 trace_rxrpc_conn(debug_id, rxrpc_conn_put_service, n, here);
340 ASSERTCMP(n, >=, 0);
341 if (n == 1)
342 rxrpc_set_service_reap_timer(conn->params.local->rxnet,
343 jiffies + rxrpc_connection_expiry);
347 * destroy a virtual connection
349 static void rxrpc_destroy_connection(struct rcu_head *rcu)
351 struct rxrpc_connection *conn =
352 container_of(rcu, struct rxrpc_connection, rcu);
354 _enter("{%d,u=%d}", conn->debug_id, atomic_read(&conn->usage));
356 ASSERTCMP(atomic_read(&conn->usage), ==, 0);
358 _net("DESTROY CONN %d", conn->debug_id);
360 del_timer_sync(&conn->timer);
361 rxrpc_purge_queue(&conn->rx_queue);
363 conn->security->clear(conn);
364 key_put(conn->params.key);
365 key_put(conn->server_key);
366 rxrpc_put_peer(conn->params.peer);
368 if (atomic_dec_and_test(&conn->params.local->rxnet->nr_conns))
369 wake_up_var(&conn->params.local->rxnet->nr_conns);
370 rxrpc_put_local(conn->params.local);
372 kfree(conn);
373 _leave("");
377 * reap dead service connections
379 void rxrpc_service_connection_reaper(struct work_struct *work)
381 struct rxrpc_connection *conn, *_p;
382 struct rxrpc_net *rxnet =
383 container_of(work, struct rxrpc_net, service_conn_reaper);
384 unsigned long expire_at, earliest, idle_timestamp, now;
386 LIST_HEAD(graveyard);
388 _enter("");
390 now = jiffies;
391 earliest = now + MAX_JIFFY_OFFSET;
393 write_lock(&rxnet->conn_lock);
394 list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
395 ASSERTCMP(atomic_read(&conn->usage), >, 0);
396 if (likely(atomic_read(&conn->usage) > 1))
397 continue;
398 if (conn->state == RXRPC_CONN_SERVICE_PREALLOC)
399 continue;
401 if (rxnet->live && !conn->params.local->dead) {
402 idle_timestamp = READ_ONCE(conn->idle_timestamp);
403 expire_at = idle_timestamp + rxrpc_connection_expiry * HZ;
404 if (conn->params.local->service_closed)
405 expire_at = idle_timestamp + rxrpc_closed_conn_expiry * HZ;
407 _debug("reap CONN %d { u=%d,t=%ld }",
408 conn->debug_id, atomic_read(&conn->usage),
409 (long)expire_at - (long)now);
411 if (time_before(now, expire_at)) {
412 if (time_before(expire_at, earliest))
413 earliest = expire_at;
414 continue;
418 /* The usage count sits at 1 whilst the object is unused on the
419 * list; we reduce that to 0 to make the object unavailable.
421 if (atomic_cmpxchg(&conn->usage, 1, 0) != 1)
422 continue;
423 trace_rxrpc_conn(conn->debug_id, rxrpc_conn_reap_service, 0, NULL);
425 if (rxrpc_conn_is_client(conn))
426 BUG();
427 else
428 rxrpc_unpublish_service_conn(conn);
430 list_move_tail(&conn->link, &graveyard);
432 write_unlock(&rxnet->conn_lock);
434 if (earliest != now + MAX_JIFFY_OFFSET) {
435 _debug("reschedule reaper %ld", (long)earliest - (long)now);
436 ASSERT(time_after(earliest, now));
437 rxrpc_set_service_reap_timer(rxnet, earliest);
440 while (!list_empty(&graveyard)) {
441 conn = list_entry(graveyard.next, struct rxrpc_connection,
442 link);
443 list_del_init(&conn->link);
445 ASSERTCMP(atomic_read(&conn->usage), ==, 0);
446 rxrpc_kill_connection(conn);
449 _leave("");
453 * preemptively destroy all the service connection records rather than
454 * waiting for them to time out
456 void rxrpc_destroy_all_connections(struct rxrpc_net *rxnet)
458 struct rxrpc_connection *conn, *_p;
459 bool leak = false;
461 _enter("");
463 atomic_dec(&rxnet->nr_conns);
464 rxrpc_destroy_all_client_connections(rxnet);
466 del_timer_sync(&rxnet->service_conn_reap_timer);
467 rxrpc_queue_work(&rxnet->service_conn_reaper);
468 flush_workqueue(rxrpc_workqueue);
470 write_lock(&rxnet->conn_lock);
471 list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
472 pr_err("AF_RXRPC: Leaked conn %p {%d}\n",
473 conn, atomic_read(&conn->usage));
474 leak = true;
476 write_unlock(&rxnet->conn_lock);
477 BUG_ON(leak);
479 ASSERT(list_empty(&rxnet->conn_proc_list));
481 /* We need to wait for the connections to be destroyed by RCU as they
482 * pin things that we still need to get rid of.
484 wait_var_event(&rxnet->nr_conns, !atomic_read(&rxnet->nr_conns));
485 _leave("");