1 /* RxRPC individual remote procedure call handling
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/slab.h>
15 #include <linux/module.h>
16 #include <linux/circ_buf.h>
17 #include <linux/spinlock_types.h>
19 #include <net/af_rxrpc.h>
20 #include "ar-internal.h"
22 const char *const rxrpc_call_states
[NR__RXRPC_CALL_STATES
] = {
23 [RXRPC_CALL_UNINITIALISED
] = "Uninit ",
24 [RXRPC_CALL_CLIENT_AWAIT_CONN
] = "ClWtConn",
25 [RXRPC_CALL_CLIENT_SEND_REQUEST
] = "ClSndReq",
26 [RXRPC_CALL_CLIENT_AWAIT_REPLY
] = "ClAwtRpl",
27 [RXRPC_CALL_CLIENT_RECV_REPLY
] = "ClRcvRpl",
28 [RXRPC_CALL_SERVER_PREALLOC
] = "SvPrealc",
29 [RXRPC_CALL_SERVER_SECURING
] = "SvSecure",
30 [RXRPC_CALL_SERVER_ACCEPTING
] = "SvAccept",
31 [RXRPC_CALL_SERVER_RECV_REQUEST
] = "SvRcvReq",
32 [RXRPC_CALL_SERVER_ACK_REQUEST
] = "SvAckReq",
33 [RXRPC_CALL_SERVER_SEND_REPLY
] = "SvSndRpl",
34 [RXRPC_CALL_SERVER_AWAIT_ACK
] = "SvAwtACK",
35 [RXRPC_CALL_COMPLETE
] = "Complete",
38 const char *const rxrpc_call_completions
[NR__RXRPC_CALL_COMPLETIONS
] = {
39 [RXRPC_CALL_SUCCEEDED
] = "Complete",
40 [RXRPC_CALL_REMOTELY_ABORTED
] = "RmtAbort",
41 [RXRPC_CALL_LOCALLY_ABORTED
] = "LocAbort",
42 [RXRPC_CALL_LOCAL_ERROR
] = "LocError",
43 [RXRPC_CALL_NETWORK_ERROR
] = "NetError",
46 struct kmem_cache
*rxrpc_call_jar
;
48 static void rxrpc_call_timer_expired(struct timer_list
*t
)
50 struct rxrpc_call
*call
= from_timer(call
, t
, timer
);
52 _enter("%d", call
->debug_id
);
54 if (call
->state
< RXRPC_CALL_COMPLETE
) {
55 trace_rxrpc_timer(call
, rxrpc_timer_expired
, jiffies
);
56 rxrpc_queue_call(call
);
60 static struct lock_class_key rxrpc_call_user_mutex_lock_class_key
;
63 * find an extant server call
64 * - called in process context with IRQs enabled
66 struct rxrpc_call
*rxrpc_find_call_by_user_ID(struct rxrpc_sock
*rx
,
67 unsigned long user_call_ID
)
69 struct rxrpc_call
*call
;
72 _enter("%p,%lx", rx
, user_call_ID
);
74 read_lock(&rx
->call_lock
);
76 p
= rx
->calls
.rb_node
;
78 call
= rb_entry(p
, struct rxrpc_call
, sock_node
);
80 if (user_call_ID
< call
->user_call_ID
)
82 else if (user_call_ID
> call
->user_call_ID
)
85 goto found_extant_call
;
88 read_unlock(&rx
->call_lock
);
93 rxrpc_get_call(call
, rxrpc_call_got
);
94 read_unlock(&rx
->call_lock
);
95 _leave(" = %p [%d]", call
, atomic_read(&call
->usage
));
100 * allocate a new call
102 struct rxrpc_call
*rxrpc_alloc_call(struct rxrpc_sock
*rx
, gfp_t gfp
,
103 unsigned int debug_id
)
105 struct rxrpc_call
*call
;
106 struct rxrpc_net
*rxnet
= rxrpc_net(sock_net(&rx
->sk
));
108 call
= kmem_cache_zalloc(rxrpc_call_jar
, gfp
);
112 call
->rxtx_buffer
= kcalloc(RXRPC_RXTX_BUFF_SIZE
,
113 sizeof(struct sk_buff
*),
115 if (!call
->rxtx_buffer
)
118 call
->rxtx_annotations
= kcalloc(RXRPC_RXTX_BUFF_SIZE
, sizeof(u8
), gfp
);
119 if (!call
->rxtx_annotations
)
122 mutex_init(&call
->user_mutex
);
124 /* Prevent lockdep reporting a deadlock false positive between the afs
125 * filesystem and sys_sendmsg() via the mmap sem.
127 if (rx
->sk
.sk_kern_sock
)
128 lockdep_set_class(&call
->user_mutex
,
129 &rxrpc_call_user_mutex_lock_class_key
);
131 timer_setup(&call
->timer
, rxrpc_call_timer_expired
, 0);
132 INIT_WORK(&call
->processor
, &rxrpc_process_call
);
133 INIT_LIST_HEAD(&call
->link
);
134 INIT_LIST_HEAD(&call
->chan_wait_link
);
135 INIT_LIST_HEAD(&call
->accept_link
);
136 INIT_LIST_HEAD(&call
->recvmsg_link
);
137 INIT_LIST_HEAD(&call
->sock_link
);
138 init_waitqueue_head(&call
->waitq
);
139 spin_lock_init(&call
->lock
);
140 spin_lock_init(&call
->notify_lock
);
141 spin_lock_init(&call
->input_lock
);
142 rwlock_init(&call
->state_lock
);
143 atomic_set(&call
->usage
, 1);
144 call
->debug_id
= debug_id
;
145 call
->tx_total_len
= -1;
146 call
->next_rx_timo
= 20 * HZ
;
147 call
->next_req_timo
= 1 * HZ
;
149 memset(&call
->sock_node
, 0xed, sizeof(call
->sock_node
));
151 /* Leave space in the ring to handle a maxed-out jumbo packet */
152 call
->rx_winsize
= rxrpc_rx_window_size
;
153 call
->tx_winsize
= 16;
154 call
->rx_expect_next
= 1;
157 call
->cong_ssthresh
= RXRPC_RXTX_BUFF_SIZE
- 1;
160 atomic_inc(&rxnet
->nr_calls
);
164 kfree(call
->rxtx_buffer
);
166 kmem_cache_free(rxrpc_call_jar
, call
);
171 * Allocate a new client call.
173 static struct rxrpc_call
*rxrpc_alloc_client_call(struct rxrpc_sock
*rx
,
174 struct sockaddr_rxrpc
*srx
,
176 unsigned int debug_id
)
178 struct rxrpc_call
*call
;
183 call
= rxrpc_alloc_call(rx
, gfp
, debug_id
);
185 return ERR_PTR(-ENOMEM
);
186 call
->state
= RXRPC_CALL_CLIENT_AWAIT_CONN
;
187 call
->service_id
= srx
->srx_service
;
188 call
->tx_phase
= true;
189 now
= ktime_get_real();
190 call
->acks_latest_ts
= now
;
191 call
->cong_tstamp
= now
;
193 _leave(" = %p", call
);
198 * Initiate the call ack/resend/expiry timer.
200 static void rxrpc_start_call_timer(struct rxrpc_call
*call
)
202 unsigned long now
= jiffies
;
203 unsigned long j
= now
+ MAX_JIFFY_OFFSET
;
206 call
->ack_lost_at
= j
;
209 call
->expect_rx_by
= j
;
210 call
->expect_req_by
= j
;
211 call
->expect_term_by
= j
;
212 call
->timer
.expires
= now
;
216 * Set up a call for the given parameters.
217 * - Called with the socket lock held, which it must release.
218 * - If it returns a call, the call's lock will need releasing by the caller.
220 struct rxrpc_call
*rxrpc_new_client_call(struct rxrpc_sock
*rx
,
221 struct rxrpc_conn_parameters
*cp
,
222 struct sockaddr_rxrpc
*srx
,
223 struct rxrpc_call_params
*p
,
225 unsigned int debug_id
)
226 __releases(&rx
->sk
.sk_lock
.slock
)
227 __acquires(&call
->user_mutex
)
229 struct rxrpc_call
*call
, *xcall
;
230 struct rxrpc_net
*rxnet
;
231 struct rb_node
*parent
, **pp
;
232 const void *here
= __builtin_return_address(0);
235 _enter("%p,%lx", rx
, p
->user_call_ID
);
237 call
= rxrpc_alloc_client_call(rx
, srx
, gfp
, debug_id
);
239 release_sock(&rx
->sk
);
240 _leave(" = %ld", PTR_ERR(call
));
244 call
->tx_total_len
= p
->tx_total_len
;
245 trace_rxrpc_call(call
, rxrpc_call_new_client
, atomic_read(&call
->usage
),
246 here
, (const void *)p
->user_call_ID
);
248 /* We need to protect a partially set up call against the user as we
249 * will be acting outside the socket lock.
251 mutex_lock(&call
->user_mutex
);
253 /* Publish the call, even though it is incompletely set up as yet */
254 write_lock(&rx
->call_lock
);
256 pp
= &rx
->calls
.rb_node
;
260 xcall
= rb_entry(parent
, struct rxrpc_call
, sock_node
);
262 if (p
->user_call_ID
< xcall
->user_call_ID
)
263 pp
= &(*pp
)->rb_left
;
264 else if (p
->user_call_ID
> xcall
->user_call_ID
)
265 pp
= &(*pp
)->rb_right
;
267 goto error_dup_user_ID
;
270 rcu_assign_pointer(call
->socket
, rx
);
271 call
->user_call_ID
= p
->user_call_ID
;
272 __set_bit(RXRPC_CALL_HAS_USERID
, &call
->flags
);
273 rxrpc_get_call(call
, rxrpc_call_got_userid
);
274 rb_link_node(&call
->sock_node
, parent
, pp
);
275 rb_insert_color(&call
->sock_node
, &rx
->calls
);
276 list_add(&call
->sock_link
, &rx
->sock_calls
);
278 write_unlock(&rx
->call_lock
);
281 write_lock(&rxnet
->call_lock
);
282 list_add_tail(&call
->link
, &rxnet
->calls
);
283 write_unlock(&rxnet
->call_lock
);
285 /* From this point on, the call is protected by its own lock. */
286 release_sock(&rx
->sk
);
288 /* Set up or get a connection record and set the protocol parameters,
289 * including channel number and call ID.
291 ret
= rxrpc_connect_call(rx
, call
, cp
, srx
, gfp
);
295 trace_rxrpc_call(call
, rxrpc_call_connected
, atomic_read(&call
->usage
),
298 rxrpc_start_call_timer(call
);
300 _net("CALL new %d on CONN %d", call
->debug_id
, call
->conn
->debug_id
);
302 _leave(" = %p [new]", call
);
305 /* We unexpectedly found the user ID in the list after taking
306 * the call_lock. This shouldn't happen unless the user races
307 * with itself and tries to add the same user ID twice at the
308 * same time in different threads.
311 write_unlock(&rx
->call_lock
);
312 release_sock(&rx
->sk
);
316 __rxrpc_set_call_completion(call
, RXRPC_CALL_LOCAL_ERROR
,
318 trace_rxrpc_call(call
, rxrpc_call_error
, atomic_read(&call
->usage
),
320 rxrpc_release_call(rx
, call
);
321 mutex_unlock(&call
->user_mutex
);
322 rxrpc_put_call(call
, rxrpc_call_put
);
323 _leave(" = %d", ret
);
328 * Set up an incoming call. call->conn points to the connection.
329 * This is called in BH context and isn't allowed to fail.
331 void rxrpc_incoming_call(struct rxrpc_sock
*rx
,
332 struct rxrpc_call
*call
,
335 struct rxrpc_connection
*conn
= call
->conn
;
336 struct rxrpc_skb_priv
*sp
= rxrpc_skb(skb
);
339 _enter(",%d", call
->conn
->debug_id
);
341 rcu_assign_pointer(call
->socket
, rx
);
342 call
->call_id
= sp
->hdr
.callNumber
;
343 call
->service_id
= sp
->hdr
.serviceId
;
344 call
->cid
= sp
->hdr
.cid
;
345 call
->state
= RXRPC_CALL_SERVER_ACCEPTING
;
346 if (sp
->hdr
.securityIndex
> 0)
347 call
->state
= RXRPC_CALL_SERVER_SECURING
;
348 call
->cong_tstamp
= skb
->tstamp
;
350 /* Set the channel for this call. We don't get channel_lock as we're
351 * only defending against the data_ready handler (which we're called
352 * from) and the RESPONSE packet parser (which is only really
353 * interested in call_counter and can cope with a disagreement with the
356 chan
= sp
->hdr
.cid
& RXRPC_CHANNELMASK
;
357 conn
->channels
[chan
].call_counter
= call
->call_id
;
358 conn
->channels
[chan
].call_id
= call
->call_id
;
359 rcu_assign_pointer(conn
->channels
[chan
].call
, call
);
361 spin_lock(&conn
->params
.peer
->lock
);
362 hlist_add_head_rcu(&call
->error_link
, &conn
->params
.peer
->error_targets
);
363 spin_unlock(&conn
->params
.peer
->lock
);
365 _net("CALL incoming %d on CONN %d", call
->debug_id
, call
->conn
->debug_id
);
367 rxrpc_start_call_timer(call
);
372 * Queue a call's work processor, getting a ref to pass to the work queue.
374 bool rxrpc_queue_call(struct rxrpc_call
*call
)
376 const void *here
= __builtin_return_address(0);
377 int n
= atomic_fetch_add_unless(&call
->usage
, 1, 0);
380 if (rxrpc_queue_work(&call
->processor
))
381 trace_rxrpc_call(call
, rxrpc_call_queued
, n
+ 1, here
, NULL
);
383 rxrpc_put_call(call
, rxrpc_call_put_noqueue
);
388 * Queue a call's work processor, passing the callers ref to the work queue.
390 bool __rxrpc_queue_call(struct rxrpc_call
*call
)
392 const void *here
= __builtin_return_address(0);
393 int n
= atomic_read(&call
->usage
);
395 if (rxrpc_queue_work(&call
->processor
))
396 trace_rxrpc_call(call
, rxrpc_call_queued_ref
, n
, here
, NULL
);
398 rxrpc_put_call(call
, rxrpc_call_put_noqueue
);
403 * Note the re-emergence of a call.
405 void rxrpc_see_call(struct rxrpc_call
*call
)
407 const void *here
= __builtin_return_address(0);
409 int n
= atomic_read(&call
->usage
);
411 trace_rxrpc_call(call
, rxrpc_call_seen
, n
, here
, NULL
);
416 * Note the addition of a ref on a call.
418 void rxrpc_get_call(struct rxrpc_call
*call
, enum rxrpc_call_trace op
)
420 const void *here
= __builtin_return_address(0);
421 int n
= atomic_inc_return(&call
->usage
);
423 trace_rxrpc_call(call
, op
, n
, here
, NULL
);
427 * Detach a call from its owning socket.
429 void rxrpc_release_call(struct rxrpc_sock
*rx
, struct rxrpc_call
*call
)
431 const void *here
= __builtin_return_address(0);
432 struct rxrpc_connection
*conn
= call
->conn
;
436 _enter("{%d,%d}", call
->debug_id
, atomic_read(&call
->usage
));
438 trace_rxrpc_call(call
, rxrpc_call_release
, atomic_read(&call
->usage
),
439 here
, (const void *)call
->flags
);
441 ASSERTCMP(call
->state
, ==, RXRPC_CALL_COMPLETE
);
443 spin_lock_bh(&call
->lock
);
444 if (test_and_set_bit(RXRPC_CALL_RELEASED
, &call
->flags
))
446 spin_unlock_bh(&call
->lock
);
448 del_timer_sync(&call
->timer
);
450 /* Make sure we don't get any more notifications */
451 write_lock_bh(&rx
->recvmsg_lock
);
453 if (!list_empty(&call
->recvmsg_link
)) {
454 _debug("unlinking once-pending call %p { e=%lx f=%lx }",
455 call
, call
->events
, call
->flags
);
456 list_del(&call
->recvmsg_link
);
460 /* list_empty() must return false in rxrpc_notify_socket() */
461 call
->recvmsg_link
.next
= NULL
;
462 call
->recvmsg_link
.prev
= NULL
;
464 write_unlock_bh(&rx
->recvmsg_lock
);
466 rxrpc_put_call(call
, rxrpc_call_put
);
468 write_lock(&rx
->call_lock
);
470 if (test_and_clear_bit(RXRPC_CALL_HAS_USERID
, &call
->flags
)) {
471 rb_erase(&call
->sock_node
, &rx
->calls
);
472 memset(&call
->sock_node
, 0xdd, sizeof(call
->sock_node
));
473 rxrpc_put_call(call
, rxrpc_call_put_userid
);
476 list_del(&call
->sock_link
);
477 write_unlock(&rx
->call_lock
);
479 _debug("RELEASE CALL %p (%d CONN %p)", call
, call
->debug_id
, conn
);
482 rxrpc_disconnect_call(call
);
484 for (i
= 0; i
< RXRPC_RXTX_BUFF_SIZE
; i
++) {
485 rxrpc_free_skb(call
->rxtx_buffer
[i
],
486 (call
->tx_phase
? rxrpc_skb_tx_cleaned
:
487 rxrpc_skb_rx_cleaned
));
488 call
->rxtx_buffer
[i
] = NULL
;
495 * release all the calls associated with a socket
497 void rxrpc_release_calls_on_socket(struct rxrpc_sock
*rx
)
499 struct rxrpc_call
*call
;
503 while (!list_empty(&rx
->to_be_accepted
)) {
504 call
= list_entry(rx
->to_be_accepted
.next
,
505 struct rxrpc_call
, accept_link
);
506 list_del(&call
->accept_link
);
507 rxrpc_abort_call("SKR", call
, 0, RX_CALL_DEAD
, -ECONNRESET
);
508 rxrpc_put_call(call
, rxrpc_call_put
);
511 while (!list_empty(&rx
->sock_calls
)) {
512 call
= list_entry(rx
->sock_calls
.next
,
513 struct rxrpc_call
, sock_link
);
514 rxrpc_get_call(call
, rxrpc_call_got
);
515 rxrpc_abort_call("SKT", call
, 0, RX_CALL_DEAD
, -ECONNRESET
);
516 rxrpc_send_abort_packet(call
);
517 rxrpc_release_call(rx
, call
);
518 rxrpc_put_call(call
, rxrpc_call_put
);
527 void rxrpc_put_call(struct rxrpc_call
*call
, enum rxrpc_call_trace op
)
529 struct rxrpc_net
*rxnet
= call
->rxnet
;
530 const void *here
= __builtin_return_address(0);
533 ASSERT(call
!= NULL
);
535 n
= atomic_dec_return(&call
->usage
);
536 trace_rxrpc_call(call
, op
, n
, here
, NULL
);
539 _debug("call %d dead", call
->debug_id
);
540 ASSERTCMP(call
->state
, ==, RXRPC_CALL_COMPLETE
);
542 if (!list_empty(&call
->link
)) {
543 write_lock(&rxnet
->call_lock
);
544 list_del_init(&call
->link
);
545 write_unlock(&rxnet
->call_lock
);
548 rxrpc_cleanup_call(call
);
553 * Final call destruction under RCU.
555 static void rxrpc_rcu_destroy_call(struct rcu_head
*rcu
)
557 struct rxrpc_call
*call
= container_of(rcu
, struct rxrpc_call
, rcu
);
558 struct rxrpc_net
*rxnet
= call
->rxnet
;
560 rxrpc_put_peer(call
->peer
);
561 kfree(call
->rxtx_buffer
);
562 kfree(call
->rxtx_annotations
);
563 kmem_cache_free(rxrpc_call_jar
, call
);
564 if (atomic_dec_and_test(&rxnet
->nr_calls
))
565 wake_up_var(&rxnet
->nr_calls
);
571 void rxrpc_cleanup_call(struct rxrpc_call
*call
)
575 _net("DESTROY CALL %d", call
->debug_id
);
577 memset(&call
->sock_node
, 0xcd, sizeof(call
->sock_node
));
579 del_timer_sync(&call
->timer
);
581 ASSERTCMP(call
->state
, ==, RXRPC_CALL_COMPLETE
);
582 ASSERT(test_bit(RXRPC_CALL_RELEASED
, &call
->flags
));
583 ASSERTCMP(call
->conn
, ==, NULL
);
585 /* Clean up the Rx/Tx buffer */
586 for (i
= 0; i
< RXRPC_RXTX_BUFF_SIZE
; i
++)
587 rxrpc_free_skb(call
->rxtx_buffer
[i
],
588 (call
->tx_phase
? rxrpc_skb_tx_cleaned
:
589 rxrpc_skb_rx_cleaned
));
591 rxrpc_free_skb(call
->tx_pending
, rxrpc_skb_tx_cleaned
);
593 call_rcu(&call
->rcu
, rxrpc_rcu_destroy_call
);
597 * Make sure that all calls are gone from a network namespace. To reach this
598 * point, any open UDP sockets in that namespace must have been closed, so any
599 * outstanding calls cannot be doing I/O.
601 void rxrpc_destroy_all_calls(struct rxrpc_net
*rxnet
)
603 struct rxrpc_call
*call
;
607 if (!list_empty(&rxnet
->calls
)) {
608 write_lock(&rxnet
->call_lock
);
610 while (!list_empty(&rxnet
->calls
)) {
611 call
= list_entry(rxnet
->calls
.next
,
612 struct rxrpc_call
, link
);
613 _debug("Zapping call %p", call
);
615 rxrpc_see_call(call
);
616 list_del_init(&call
->link
);
618 pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
619 call
, atomic_read(&call
->usage
),
620 rxrpc_call_states
[call
->state
],
621 call
->flags
, call
->events
);
623 write_unlock(&rxnet
->call_lock
);
625 write_lock(&rxnet
->call_lock
);
628 write_unlock(&rxnet
->call_lock
);
631 atomic_dec(&rxnet
->nr_calls
);
632 wait_var_event(&rxnet
->nr_calls
, !atomic_read(&rxnet
->nr_calls
));