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)
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
;
41 conn
= kzalloc(sizeof(struct rxrpc_connection
), gfp
);
43 INIT_LIST_HEAD(&conn
->cache_link
);
44 timer_setup(&conn
->timer
, &rxrpc_connection_timer
, 0);
45 INIT_WORK(&conn
->processor
, &rxrpc_process_connection
);
46 INIT_LIST_HEAD(&conn
->proc_link
);
47 INIT_LIST_HEAD(&conn
->link
);
48 skb_queue_head_init(&conn
->rx_queue
);
49 conn
->security
= &rxrpc_no_security
;
50 spin_lock_init(&conn
->state_lock
);
51 conn
->debug_id
= atomic_inc_return(&rxrpc_debug_id
);
52 conn
->idle_timestamp
= jiffies
;
55 _leave(" = %p{%d}", conn
, conn
? conn
->debug_id
: 0);
60 * Look up a connection in the cache by protocol parameters.
62 * If successful, a pointer to the connection is returned, but no ref is taken.
63 * NULL is returned if there is no match.
65 * When searching for a service call, if we find a peer but no connection, we
66 * return that through *_peer in case we need to create a new service call.
68 * The caller must be holding the RCU read lock.
70 struct rxrpc_connection
*rxrpc_find_connection_rcu(struct rxrpc_local
*local
,
72 struct rxrpc_peer
**_peer
)
74 struct rxrpc_connection
*conn
;
75 struct rxrpc_conn_proto k
;
76 struct rxrpc_skb_priv
*sp
= rxrpc_skb(skb
);
77 struct sockaddr_rxrpc srx
;
78 struct rxrpc_peer
*peer
;
80 _enter(",%x", sp
->hdr
.cid
& RXRPC_CIDMASK
);
82 if (rxrpc_extract_addr_from_skb(&srx
, skb
) < 0)
85 if (srx
.transport
.family
!= local
->srx
.transport
.family
&&
86 (srx
.transport
.family
== AF_INET
&&
87 local
->srx
.transport
.family
!= AF_INET6
)) {
88 pr_warn_ratelimited("AF_RXRPC: Protocol mismatch %u not %u\n",
90 local
->srx
.transport
.family
);
94 k
.epoch
= sp
->hdr
.epoch
;
95 k
.cid
= sp
->hdr
.cid
& RXRPC_CIDMASK
;
97 if (rxrpc_to_server(sp
)) {
98 /* We need to look up service connections by the full protocol
99 * parameter set. We look up the peer first as an intermediate
100 * step and then the connection from the peer's tree.
102 peer
= rxrpc_lookup_peer_rcu(local
, &srx
);
106 conn
= rxrpc_find_service_conn_rcu(peer
, skb
);
107 if (!conn
|| atomic_read(&conn
->usage
) == 0)
109 _leave(" = %p", conn
);
112 /* Look up client connections by connection ID alone as their
113 * IDs are unique for this machine.
115 conn
= idr_find(&rxrpc_client_conn_ids
,
116 sp
->hdr
.cid
>> RXRPC_CIDSHIFT
);
117 if (!conn
|| atomic_read(&conn
->usage
) == 0) {
122 if (conn
->proto
.epoch
!= k
.epoch
||
123 conn
->params
.local
!= local
)
126 peer
= conn
->params
.peer
;
127 switch (srx
.transport
.family
) {
129 if (peer
->srx
.transport
.sin
.sin_port
!=
130 srx
.transport
.sin
.sin_port
||
131 peer
->srx
.transport
.sin
.sin_addr
.s_addr
!=
132 srx
.transport
.sin
.sin_addr
.s_addr
)
135 #ifdef CONFIG_AF_RXRPC_IPV6
137 if (peer
->srx
.transport
.sin6
.sin6_port
!=
138 srx
.transport
.sin6
.sin6_port
||
139 memcmp(&peer
->srx
.transport
.sin6
.sin6_addr
,
140 &srx
.transport
.sin6
.sin6_addr
,
141 sizeof(struct in6_addr
)) != 0)
149 _leave(" = %p", conn
);
159 * Disconnect a call and clear any channel it occupies when that call
160 * terminates. The caller must hold the channel_lock and must release the
161 * call's ref on the connection.
163 void __rxrpc_disconnect_call(struct rxrpc_connection
*conn
,
164 struct rxrpc_call
*call
)
166 struct rxrpc_channel
*chan
=
167 &conn
->channels
[call
->cid
& RXRPC_CHANNELMASK
];
169 _enter("%d,%x", conn
->debug_id
, call
->cid
);
171 if (rcu_access_pointer(chan
->call
) == call
) {
172 /* Save the result of the call so that we can repeat it if necessary
173 * through the channel, whilst disposing of the actual call record.
175 trace_rxrpc_disconnect_call(call
);
176 switch (call
->completion
) {
177 case RXRPC_CALL_SUCCEEDED
:
178 chan
->last_seq
= call
->rx_hard_ack
;
179 chan
->last_type
= RXRPC_PACKET_TYPE_ACK
;
181 case RXRPC_CALL_LOCALLY_ABORTED
:
182 chan
->last_abort
= call
->abort_code
;
183 chan
->last_type
= RXRPC_PACKET_TYPE_ABORT
;
186 chan
->last_abort
= RX_USER_ABORT
;
187 chan
->last_type
= RXRPC_PACKET_TYPE_ABORT
;
191 /* Sync with rxrpc_conn_retransmit(). */
193 chan
->last_call
= chan
->call_id
;
194 chan
->call_id
= chan
->call_counter
;
196 rcu_assign_pointer(chan
->call
, NULL
);
203 * Disconnect a call and clear any channel it occupies when that call
206 void rxrpc_disconnect_call(struct rxrpc_call
*call
)
208 struct rxrpc_connection
*conn
= call
->conn
;
210 call
->peer
->cong_cwnd
= call
->cong_cwnd
;
212 if (!hlist_unhashed(&call
->error_link
)) {
213 spin_lock_bh(&call
->peer
->lock
);
214 hlist_del_rcu(&call
->error_link
);
215 spin_unlock_bh(&call
->peer
->lock
);
218 if (rxrpc_is_client_call(call
))
219 return rxrpc_disconnect_client_call(conn
->bundle
, call
);
221 spin_lock(&conn
->bundle
->channel_lock
);
222 __rxrpc_disconnect_call(conn
, call
);
223 spin_unlock(&conn
->bundle
->channel_lock
);
225 set_bit(RXRPC_CALL_DISCONNECTED
, &call
->flags
);
226 conn
->idle_timestamp
= jiffies
;
230 * Kill off a connection.
232 void rxrpc_kill_connection(struct rxrpc_connection
*conn
)
234 struct rxrpc_net
*rxnet
= conn
->params
.local
->rxnet
;
236 ASSERT(!rcu_access_pointer(conn
->channels
[0].call
) &&
237 !rcu_access_pointer(conn
->channels
[1].call
) &&
238 !rcu_access_pointer(conn
->channels
[2].call
) &&
239 !rcu_access_pointer(conn
->channels
[3].call
));
240 ASSERT(list_empty(&conn
->cache_link
));
242 write_lock(&rxnet
->conn_lock
);
243 list_del_init(&conn
->proc_link
);
244 write_unlock(&rxnet
->conn_lock
);
246 /* Drain the Rx queue. Note that even though we've unpublished, an
247 * incoming packet could still be being added to our Rx queue, so we
248 * will need to drain it again in the RCU cleanup handler.
250 rxrpc_purge_queue(&conn
->rx_queue
);
252 /* Leave final destruction to RCU. The connection processor work item
253 * must carry a ref on the connection to prevent us getting here whilst
254 * it is queued or running.
256 call_rcu(&conn
->rcu
, rxrpc_destroy_connection
);
260 * Queue a connection's work processor, getting a ref to pass to the work
263 bool rxrpc_queue_conn(struct rxrpc_connection
*conn
)
265 const void *here
= __builtin_return_address(0);
266 int n
= atomic_fetch_add_unless(&conn
->usage
, 1, 0);
269 if (rxrpc_queue_work(&conn
->processor
))
270 trace_rxrpc_conn(conn
->debug_id
, rxrpc_conn_queued
, n
+ 1, here
);
272 rxrpc_put_connection(conn
);
277 * Note the re-emergence of a connection.
279 void rxrpc_see_connection(struct rxrpc_connection
*conn
)
281 const void *here
= __builtin_return_address(0);
283 int n
= atomic_read(&conn
->usage
);
285 trace_rxrpc_conn(conn
->debug_id
, rxrpc_conn_seen
, n
, here
);
290 * Get a ref on a connection.
292 struct rxrpc_connection
*rxrpc_get_connection(struct rxrpc_connection
*conn
)
294 const void *here
= __builtin_return_address(0);
295 int n
= atomic_inc_return(&conn
->usage
);
297 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);
310 int n
= atomic_fetch_add_unless(&conn
->usage
, 1, 0);
312 trace_rxrpc_conn(conn
->debug_id
, rxrpc_conn_got
, n
+ 1, here
);
320 * Set the service connection reap timer.
322 static void rxrpc_set_service_reap_timer(struct rxrpc_net
*rxnet
,
323 unsigned long reap_at
)
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
;
338 n
= atomic_dec_return(&conn
->usage
);
339 trace_rxrpc_conn(debug_id
, rxrpc_conn_put_service
, n
, here
);
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 rxrpc_put_bundle(conn
->bundle
);
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
);
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
);
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))
398 if (conn
->state
== RXRPC_CONN_SERVICE_PREALLOC
)
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
;
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)
423 trace_rxrpc_conn(conn
->debug_id
, rxrpc_conn_reap_service
, 0, NULL
);
425 if (rxrpc_conn_is_client(conn
))
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
,
443 list_del_init(&conn
->link
);
445 ASSERTCMP(atomic_read(&conn
->usage
), ==, 0);
446 rxrpc_kill_connection(conn
);
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
;
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
));
476 write_unlock(&rxnet
->conn_lock
);
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
));