1// SPDX-License-Identifier: GPL-2.0-or-later
2/* Maintain an RxRPC server socket to do AFS communications through
3 *
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8#include <linux/slab.h>
9#include <linux/sched/signal.h>
10
11#include <net/sock.h>
12#include <net/af_rxrpc.h>
13#include "internal.h"
14#include "afs_cm.h"
15#include "protocol_yfs.h"
16#define RXRPC_TRACE_ONLY_DEFINE_ENUMS
17#include <trace/events/rxrpc.h>
18
19struct workqueue_struct *afs_async_calls;
20
21static void afs_deferred_free_worker(struct work_struct *work);
22static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long);
23static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long);
24static void afs_process_async_call(struct work_struct *);
25static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long);
26static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long);
27static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID);
28static void afs_rx_notify_oob(struct sock *sk, struct sk_buff *oob);
29static int afs_deliver_cm_op_id(struct afs_call *);
30
31static const struct rxrpc_kernel_ops afs_rxrpc_callback_ops = {
32 .notify_new_call = afs_rx_new_call,
33 .discard_new_call = afs_rx_discard_new_call,
34 .user_attach_call = afs_rx_attach,
35 .notify_oob = afs_rx_notify_oob,
36};
37
38/* asynchronous incoming call initial processing */
39static const struct afs_call_type afs_RXCMxxxx = {
40 .name = "CB.xxxx",
41 .deliver = afs_deliver_cm_op_id,
42};
43
44/*
45 * open an RxRPC socket and bind it to be a server for callback notifications
46 * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
47 */
48int afs_open_socket(struct afs_net *net)
49{
50 struct sockaddr_rxrpc srx;
51 struct socket *socket;
52 int ret;
53
54 _enter("");
55
56 ret = sock_create_kern(net: net->net, AF_RXRPC, type: SOCK_DGRAM, PF_INET6, res: &socket);
57 if (ret < 0)
58 goto error_1;
59
60 socket->sk->sk_allocation = GFP_NOFS;
61 socket->sk->sk_user_data = net;
62
63 /* bind the callback manager's address to make this a server socket */
64 memset(&srx, 0, sizeof(srx));
65 srx.srx_family = AF_RXRPC;
66 srx.srx_service = CM_SERVICE;
67 srx.transport_type = SOCK_DGRAM;
68 srx.transport_len = sizeof(srx.transport.sin6);
69 srx.transport.sin6.sin6_family = AF_INET6;
70 srx.transport.sin6.sin6_port = htons(AFS_CM_PORT);
71
72 ret = rxrpc_sock_set_min_security_level(sk: socket->sk,
73 RXRPC_SECURITY_ENCRYPT);
74 if (ret < 0)
75 goto error_2;
76
77 ret = rxrpc_sock_set_manage_response(sk: socket->sk, set: true);
78 if (ret < 0)
79 goto error_2;
80
81 ret = afs_create_token_key(net, socket);
82 if (ret < 0)
83 pr_err("Couldn't create RxGK CM key: %d\n", ret);
84
85 ret = kernel_bind(sock: socket, addr: (struct sockaddr_unsized *) &srx, addrlen: sizeof(srx));
86 if (ret == -EADDRINUSE) {
87 srx.transport.sin6.sin6_port = 0;
88 ret = kernel_bind(sock: socket, addr: (struct sockaddr_unsized *) &srx, addrlen: sizeof(srx));
89 }
90 if (ret < 0)
91 goto error_2;
92
93 srx.srx_service = YFS_CM_SERVICE;
94 ret = kernel_bind(sock: socket, addr: (struct sockaddr_unsized *) &srx, addrlen: sizeof(srx));
95 if (ret < 0)
96 goto error_2;
97
98 /* Ideally, we'd turn on service upgrade here, but we can't because
99 * OpenAFS is buggy and leaks the userStatus field from packet to
100 * packet and between FS packets and CB packets - so if we try to do an
101 * upgrade on an FS packet, OpenAFS will leak that into the CB packet
102 * it sends back to us.
103 */
104
105 rxrpc_kernel_set_notifications(sock: socket, app_ops: &afs_rxrpc_callback_ops);
106
107 ret = kernel_listen(sock: socket, INT_MAX);
108 if (ret < 0)
109 goto error_2;
110
111 net->socket = socket;
112 afs_charge_preallocation(&net->charge_preallocation_work);
113 _leave(" = 0");
114 return 0;
115
116error_2:
117 sock_release(sock: socket);
118error_1:
119 _leave(" = %d", ret);
120 return ret;
121}
122
123/*
124 * close the RxRPC socket AFS was using
125 */
126void afs_close_socket(struct afs_net *net)
127{
128 _enter("");
129
130 kernel_listen(sock: net->socket, backlog: 0);
131 flush_workqueue(afs_async_calls);
132
133 if (net->spare_incoming_call) {
134 afs_put_call(net->spare_incoming_call);
135 net->spare_incoming_call = NULL;
136 }
137
138 _debug("outstanding %u", atomic_read(&net->nr_outstanding_calls));
139 wait_var_event(&net->nr_outstanding_calls,
140 !atomic_read(&net->nr_outstanding_calls));
141 _debug("no outstanding calls");
142
143 kernel_sock_shutdown(sock: net->socket, how: SHUT_RDWR);
144 flush_workqueue(afs_async_calls);
145 net->socket->sk->sk_user_data = NULL;
146 sock_release(sock: net->socket);
147 key_put(key: net->fs_cm_token_key);
148
149 _debug("dework");
150 _leave("");
151}
152
153/*
154 * Allocate a call.
155 */
156static struct afs_call *afs_alloc_call(struct afs_net *net,
157 const struct afs_call_type *type,
158 gfp_t gfp)
159{
160 struct afs_call *call;
161 int o;
162
163 call = kzalloc(sizeof(*call), gfp);
164 if (!call)
165 return NULL;
166
167 call->type = type;
168 call->net = net;
169 call->debug_id = atomic_inc_return(v: &rxrpc_debug_id);
170 refcount_set(r: &call->ref, n: 1);
171 INIT_WORK(&call->async_work, type->async_rx ?: afs_process_async_call);
172 INIT_WORK(&call->work, call->type->work);
173 INIT_WORK(&call->free_work, afs_deferred_free_worker);
174 init_waitqueue_head(&call->waitq);
175 spin_lock_init(&call->state_lock);
176 call->iter = &call->def_iter;
177
178 o = atomic_inc_return(v: &net->nr_outstanding_calls);
179 trace_afs_call(call_debug_id: call->debug_id, op: afs_call_trace_alloc, ref: 1, outstanding: o,
180 where: __builtin_return_address(0));
181 return call;
182}
183
184static void afs_free_call(struct afs_call *call)
185{
186 struct afs_net *net = call->net;
187 int o;
188
189 ASSERT(!work_pending(&call->async_work));
190
191 rxrpc_kernel_put_peer(peer: call->peer);
192
193 if (call->rxcall) {
194 rxrpc_kernel_shutdown_call(sock: net->socket, call: call->rxcall);
195 rxrpc_kernel_put_call(sock: net->socket, call: call->rxcall);
196 call->rxcall = NULL;
197 }
198 if (call->type->destructor)
199 call->type->destructor(call);
200
201 afs_unuse_server_notime(net: call->net, server: call->server, reason: afs_server_trace_unuse_call);
202 kfree(objp: call->request);
203
204 o = atomic_read(v: &net->nr_outstanding_calls);
205 trace_afs_call(call_debug_id: call->debug_id, op: afs_call_trace_free, ref: 0, outstanding: o,
206 where: __builtin_return_address(0));
207 kfree(objp: call);
208
209 o = atomic_dec_return(v: &net->nr_outstanding_calls);
210 if (o == 0)
211 wake_up_var(var: &net->nr_outstanding_calls);
212}
213
214/*
215 * Dispose of a reference on a call.
216 */
217void afs_put_call(struct afs_call *call)
218{
219 struct afs_net *net = call->net;
220 unsigned int debug_id = call->debug_id;
221 bool zero;
222 int r, o;
223
224 zero = __refcount_dec_and_test(r: &call->ref, oldp: &r);
225 o = atomic_read(v: &net->nr_outstanding_calls);
226 trace_afs_call(call_debug_id: debug_id, op: afs_call_trace_put, ref: r - 1, outstanding: o,
227 where: __builtin_return_address(0));
228 if (zero)
229 afs_free_call(call);
230}
231
232static void afs_deferred_free_worker(struct work_struct *work)
233{
234 struct afs_call *call = container_of(work, struct afs_call, free_work);
235
236 afs_free_call(call);
237}
238
239/*
240 * Dispose of a reference on a call, deferring the cleanup to a workqueue
241 * to avoid lock recursion.
242 */
243void afs_deferred_put_call(struct afs_call *call)
244{
245 struct afs_net *net = call->net;
246 unsigned int debug_id = call->debug_id;
247 bool zero;
248 int r, o;
249
250 zero = __refcount_dec_and_test(r: &call->ref, oldp: &r);
251 o = atomic_read(v: &net->nr_outstanding_calls);
252 trace_afs_call(call_debug_id: debug_id, op: afs_call_trace_put, ref: r - 1, outstanding: o,
253 where: __builtin_return_address(0));
254 if (zero)
255 schedule_work(work: &call->free_work);
256}
257
258/*
259 * Queue the call for actual work.
260 */
261static void afs_queue_call_work(struct afs_call *call)
262{
263 if (call->type->work) {
264 afs_get_call(call, why: afs_call_trace_work);
265 if (!queue_work(wq: afs_wq, work: &call->work))
266 afs_put_call(call);
267 }
268}
269
270/*
271 * allocate a call with flat request and reply buffers
272 */
273struct afs_call *afs_alloc_flat_call(struct afs_net *net,
274 const struct afs_call_type *type,
275 size_t request_size, size_t reply_max)
276{
277 struct afs_call *call;
278
279 call = afs_alloc_call(net, type, GFP_NOFS);
280 if (!call)
281 goto nomem_call;
282
283 if (request_size) {
284 call->request_size = request_size;
285 call->request = kmalloc(request_size, GFP_NOFS);
286 if (!call->request)
287 goto nomem_free;
288 }
289
290 if (reply_max) {
291 call->reply_max = reply_max;
292 call->buffer = kmalloc(reply_max, GFP_NOFS);
293 if (!call->buffer)
294 goto nomem_free;
295 }
296
297 afs_extract_to_buf(call, size: call->reply_max);
298 call->operation_ID = type->op;
299 init_waitqueue_head(&call->waitq);
300 return call;
301
302nomem_free:
303 afs_put_call(call);
304nomem_call:
305 return NULL;
306}
307
308/*
309 * clean up a call with flat buffer
310 */
311void afs_flat_call_destructor(struct afs_call *call)
312{
313 _enter("");
314
315 kfree(objp: call->request);
316 call->request = NULL;
317 kfree(objp: call->buffer);
318 call->buffer = NULL;
319}
320
321/*
322 * Advance the AFS call state when the RxRPC call ends the transmit phase.
323 */
324static void afs_notify_end_request_tx(struct sock *sock,
325 struct rxrpc_call *rxcall,
326 unsigned long call_user_ID)
327{
328 struct afs_call *call = (struct afs_call *)call_user_ID;
329
330 afs_set_call_state(call, from: AFS_CALL_CL_REQUESTING, to: AFS_CALL_CL_AWAIT_REPLY);
331}
332
333/*
334 * Initiate a call and synchronously queue up the parameters for dispatch. Any
335 * error is stored into the call struct, which the caller must check for.
336 */
337void afs_make_call(struct afs_call *call, gfp_t gfp)
338{
339 struct rxrpc_call *rxcall;
340 struct msghdr msg;
341 struct kvec iov[1];
342 size_t len;
343 s64 tx_total_len;
344 int ret;
345
346 _enter(",{%pISp+%u},", rxrpc_kernel_remote_addr(call->peer), call->service_id);
347
348 ASSERT(call->type != NULL);
349 ASSERT(call->type->name != NULL);
350
351 _debug("____MAKE %p{%s,%x} [%d]____",
352 call, call->type->name, key_serial(call->key),
353 atomic_read(&call->net->nr_outstanding_calls));
354
355 trace_afs_make_call(call);
356
357 /* Work out the length we're going to transmit. This is awkward for
358 * calls such as FS.StoreData where there's an extra injection of data
359 * after the initial fixed part.
360 */
361 tx_total_len = call->request_size;
362 if (call->write_iter)
363 tx_total_len += iov_iter_count(i: call->write_iter);
364
365 /* If the call is going to be asynchronous, we need an extra ref for
366 * the call to hold itself so the caller need not hang on to its ref.
367 */
368 if (call->async) {
369 afs_get_call(call, why: afs_call_trace_get);
370 call->drop_ref = true;
371 }
372
373 /* create a call */
374 rxcall = rxrpc_kernel_begin_call(sock: call->net->socket, peer: call->peer, key: call->key,
375 user_call_ID: (unsigned long)call,
376 tx_total_len,
377 hard_timeout: call->max_lifespan,
378 gfp,
379 notify_rx: (call->async ?
380 afs_wake_up_async_call :
381 afs_wake_up_call_waiter),
382 service_id: call->service_id,
383 upgrade: call->upgrade,
384 interruptibility: (call->intr ? RXRPC_PREINTERRUPTIBLE :
385 RXRPC_UNINTERRUPTIBLE),
386 debug_id: call->debug_id);
387 if (IS_ERR(ptr: rxcall)) {
388 ret = PTR_ERR(ptr: rxcall);
389 call->error = ret;
390 goto error_kill_call;
391 }
392
393 call->rxcall = rxcall;
394 call->issue_time = ktime_get_real();
395
396 /* send the request */
397 iov[0].iov_base = call->request;
398 iov[0].iov_len = call->request_size;
399
400 msg.msg_name = NULL;
401 msg.msg_namelen = 0;
402 iov_iter_kvec(i: &msg.msg_iter, ITER_SOURCE, kvec: iov, nr_segs: 1, count: call->request_size);
403 msg.msg_control = NULL;
404 msg.msg_controllen = 0;
405 msg.msg_flags = MSG_WAITALL | (call->write_iter ? MSG_MORE : 0);
406
407 ret = rxrpc_kernel_send_data(call->net->socket, rxcall,
408 &msg, call->request_size,
409 afs_notify_end_request_tx);
410 if (ret < 0)
411 goto error_do_abort;
412
413 if (call->write_iter) {
414 msg.msg_iter = *call->write_iter;
415 msg.msg_flags &= ~MSG_MORE;
416 trace_afs_send_data(call, msg: &msg);
417
418 ret = rxrpc_kernel_send_data(call->net->socket,
419 call->rxcall, &msg,
420 iov_iter_count(i: &msg.msg_iter),
421 afs_notify_end_request_tx);
422 *call->write_iter = msg.msg_iter;
423
424 trace_afs_sent_data(call, msg: &msg, ret);
425 if (ret < 0)
426 goto error_do_abort;
427 }
428
429 /* Note that at this point, we may have received the reply or an abort
430 * - and an asynchronous call may already have completed.
431 *
432 * afs_wait_for_call_to_complete(call)
433 * must be called to synchronously clean up.
434 */
435 return;
436
437error_do_abort:
438 if (ret != -ECONNABORTED)
439 rxrpc_kernel_abort_call(call->net->socket, rxcall,
440 RX_USER_ABORT, ret,
441 afs_abort_send_data_error);
442 if (call->async) {
443 afs_see_call(call, why: afs_call_trace_async_abort);
444 return;
445 }
446
447 if (ret == -ECONNABORTED) {
448 len = 0;
449 iov_iter_kvec(i: &msg.msg_iter, ITER_DEST, NULL, nr_segs: 0, count: 0);
450 rxrpc_kernel_recv_data(call->net->socket, rxcall,
451 &msg.msg_iter, &len, false,
452 &call->abort_code, &call->service_id);
453 call->responded = true;
454 }
455 call->error = ret;
456 trace_afs_call_done(call);
457error_kill_call:
458 if (call->async)
459 afs_see_call(call, why: afs_call_trace_async_kill);
460 if (call->type->immediate_cancel)
461 call->type->immediate_cancel(call);
462
463 /* We need to dispose of the extra ref we grabbed for an async call.
464 * The call, however, might be queued on afs_async_calls and we need to
465 * make sure we don't get any more notifications that might requeue it.
466 */
467 if (call->rxcall)
468 rxrpc_kernel_shutdown_call(sock: call->net->socket, call: call->rxcall);
469 if (call->async) {
470 if (cancel_work_sync(work: &call->async_work))
471 afs_put_call(call);
472 afs_set_call_complete(call, error: ret, remote_abort: 0);
473 }
474
475 call->error = ret;
476 call->state = AFS_CALL_COMPLETE;
477 _leave(" = %d", ret);
478}
479
480/*
481 * Log remote abort codes that indicate that we have a protocol disagreement
482 * with the server.
483 */
484static void afs_log_error(struct afs_call *call, s32 remote_abort)
485{
486 static int max = 0;
487 const char *msg;
488 int m;
489
490 switch (remote_abort) {
491 case RX_EOF: msg = "unexpected EOF"; break;
492 case RXGEN_CC_MARSHAL: msg = "client marshalling"; break;
493 case RXGEN_CC_UNMARSHAL: msg = "client unmarshalling"; break;
494 case RXGEN_SS_MARSHAL: msg = "server marshalling"; break;
495 case RXGEN_SS_UNMARSHAL: msg = "server unmarshalling"; break;
496 case RXGEN_DECODE: msg = "opcode decode"; break;
497 case RXGEN_SS_XDRFREE: msg = "server XDR cleanup"; break;
498 case RXGEN_CC_XDRFREE: msg = "client XDR cleanup"; break;
499 case -32: msg = "insufficient data"; break;
500 default:
501 return;
502 }
503
504 m = max;
505 if (m < 3) {
506 max = m + 1;
507 pr_notice("kAFS: Peer reported %s failure on %s [%pISp]\n",
508 msg, call->type->name,
509 rxrpc_kernel_remote_addr(call->peer));
510 }
511}
512
513/*
514 * deliver messages to a call
515 */
516void afs_deliver_to_call(struct afs_call *call)
517{
518 enum afs_call_state state;
519 size_t len;
520 u32 abort_code, remote_abort = 0;
521 int ret;
522
523 _enter("%s", call->type->name);
524
525 while (state = READ_ONCE(call->state),
526 state == AFS_CALL_CL_AWAIT_REPLY ||
527 state == AFS_CALL_SV_AWAIT_OP_ID ||
528 state == AFS_CALL_SV_AWAIT_REQUEST ||
529 state == AFS_CALL_SV_AWAIT_ACK
530 ) {
531 if (state == AFS_CALL_SV_AWAIT_ACK) {
532 len = 0;
533 iov_iter_kvec(i: &call->def_iter, ITER_DEST, NULL, nr_segs: 0, count: 0);
534 ret = rxrpc_kernel_recv_data(call->net->socket,
535 call->rxcall, &call->def_iter,
536 &len, false, &remote_abort,
537 &call->service_id);
538 trace_afs_receive_data(call, iter: &call->def_iter, want_more: false, ret);
539
540 if (ret == -EINPROGRESS || ret == -EAGAIN)
541 return;
542 if (ret < 0 || ret == 1) {
543 if (ret == 1)
544 ret = 0;
545 goto call_complete;
546 }
547 return;
548 }
549
550 ret = call->type->deliver(call);
551 state = READ_ONCE(call->state);
552 if (ret == 0 && call->unmarshalling_error)
553 ret = -EBADMSG;
554 switch (ret) {
555 case 0:
556 call->responded = true;
557 afs_queue_call_work(call);
558 if (state == AFS_CALL_CL_PROC_REPLY) {
559 if (call->op)
560 set_bit(AFS_SERVER_FL_MAY_HAVE_CB,
561 addr: &call->op->server->flags);
562 goto call_complete;
563 }
564 ASSERTCMP(state, >, AFS_CALL_CL_PROC_REPLY);
565 goto done;
566 case -EINPROGRESS:
567 case -EAGAIN:
568 goto out;
569 case -ECONNABORTED:
570 ASSERTCMP(state, ==, AFS_CALL_COMPLETE);
571 call->responded = true;
572 afs_log_error(call, remote_abort: call->abort_code);
573 goto done;
574 case -ENOTSUPP:
575 call->responded = true;
576 abort_code = RXGEN_OPCODE;
577 rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
578 abort_code, ret,
579 afs_abort_op_not_supported);
580 goto local_abort;
581 case -EIO:
582 pr_err("kAFS: Call %u in bad state %u\n",
583 call->debug_id, state);
584 fallthrough;
585 case -ENODATA:
586 case -EBADMSG:
587 case -EMSGSIZE:
588 case -ENOMEM:
589 case -EFAULT:
590 abort_code = RXGEN_CC_UNMARSHAL;
591 if (state != AFS_CALL_CL_AWAIT_REPLY)
592 abort_code = RXGEN_SS_UNMARSHAL;
593 rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
594 abort_code, ret,
595 afs_abort_unmarshal_error);
596 goto local_abort;
597 default:
598 abort_code = RX_CALL_DEAD;
599 rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
600 abort_code, ret,
601 afs_abort_general_error);
602 goto local_abort;
603 }
604 }
605
606done:
607 if (call->type->done)
608 call->type->done(call);
609out:
610 _leave("");
611 return;
612
613local_abort:
614 abort_code = 0;
615call_complete:
616 afs_set_call_complete(call, error: ret, remote_abort);
617 goto done;
618}
619
620/*
621 * Wait synchronously for a call to complete.
622 */
623void afs_wait_for_call_to_complete(struct afs_call *call)
624{
625 bool rxrpc_complete = false;
626
627 _enter("");
628
629 if (!afs_check_call_state(call, state: AFS_CALL_COMPLETE)) {
630 DECLARE_WAITQUEUE(myself, current);
631
632 add_wait_queue(wq_head: &call->waitq, wq_entry: &myself);
633 for (;;) {
634 set_current_state(TASK_UNINTERRUPTIBLE);
635
636 /* deliver any messages that are in the queue */
637 if (!afs_check_call_state(call, state: AFS_CALL_COMPLETE) &&
638 call->need_attention) {
639 call->need_attention = false;
640 __set_current_state(TASK_RUNNING);
641 afs_deliver_to_call(call);
642 continue;
643 }
644
645 if (afs_check_call_state(call, state: AFS_CALL_COMPLETE))
646 break;
647
648 if (!rxrpc_kernel_check_life(call->net->socket, call->rxcall)) {
649 /* rxrpc terminated the call. */
650 rxrpc_complete = true;
651 break;
652 }
653
654 schedule();
655 }
656
657 remove_wait_queue(wq_head: &call->waitq, wq_entry: &myself);
658 __set_current_state(TASK_RUNNING);
659 }
660
661 if (!afs_check_call_state(call, state: AFS_CALL_COMPLETE)) {
662 if (rxrpc_complete) {
663 afs_set_call_complete(call, error: call->error, remote_abort: call->abort_code);
664 } else {
665 /* Kill off the call if it's still live. */
666 _debug("call interrupted");
667 if (rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
668 RX_USER_ABORT, -EINTR,
669 afs_abort_interrupted))
670 afs_set_call_complete(call, error: -EINTR, remote_abort: 0);
671 }
672 }
673}
674
675/*
676 * wake up a waiting call
677 */
678static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall,
679 unsigned long call_user_ID)
680{
681 struct afs_call *call = (struct afs_call *)call_user_ID;
682
683 call->need_attention = true;
684 wake_up(&call->waitq);
685}
686
687/*
688 * Wake up an asynchronous call. The caller is holding the call notify
689 * spinlock around this, so we can't call afs_put_call().
690 */
691static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall,
692 unsigned long call_user_ID)
693{
694 struct afs_call *call = (struct afs_call *)call_user_ID;
695 int r;
696
697 trace_afs_notify_call(rxcall, call);
698 call->need_attention = true;
699
700 if (__refcount_inc_not_zero(r: &call->ref, oldp: &r)) {
701 trace_afs_call(call_debug_id: call->debug_id, op: afs_call_trace_wake, ref: r + 1,
702 outstanding: atomic_read(v: &call->net->nr_outstanding_calls),
703 where: __builtin_return_address(0));
704
705 if (!queue_work(wq: afs_async_calls, work: &call->async_work))
706 afs_deferred_put_call(call);
707 }
708}
709
710/*
711 * Perform I/O processing on an asynchronous call. The work item carries a ref
712 * to the call struct that we either need to release or to pass on.
713 */
714static void afs_process_async_call(struct work_struct *work)
715{
716 struct afs_call *call = container_of(work, struct afs_call, async_work);
717
718 _enter("");
719
720 if (call->state < AFS_CALL_COMPLETE && call->need_attention) {
721 call->need_attention = false;
722 afs_deliver_to_call(call);
723 }
724
725 afs_put_call(call);
726 _leave("");
727}
728
729static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID)
730{
731 struct afs_call *call = (struct afs_call *)user_call_ID;
732
733 call->rxcall = rxcall;
734}
735
736/*
737 * Charge the incoming call preallocation.
738 */
739void afs_charge_preallocation(struct work_struct *work)
740{
741 struct afs_net *net =
742 container_of(work, struct afs_net, charge_preallocation_work);
743 struct afs_call *call = net->spare_incoming_call;
744
745 for (;;) {
746 if (!call) {
747 call = afs_alloc_call(net, type: &afs_RXCMxxxx, GFP_KERNEL);
748 if (!call)
749 break;
750
751 call->drop_ref = true;
752 call->async = true;
753 call->state = AFS_CALL_SV_AWAIT_OP_ID;
754 init_waitqueue_head(&call->waitq);
755 afs_extract_to_tmp(call);
756 }
757
758 if (rxrpc_kernel_charge_accept(sock: net->socket,
759 notify_rx: afs_wake_up_async_call,
760 user_call_ID: (unsigned long)call,
761 GFP_KERNEL,
762 debug_id: call->debug_id) < 0)
763 break;
764 call = NULL;
765 }
766 net->spare_incoming_call = call;
767}
768
769/*
770 * Discard a preallocated call when a socket is shut down.
771 */
772static void afs_rx_discard_new_call(struct rxrpc_call *rxcall,
773 unsigned long user_call_ID)
774{
775 struct afs_call *call = (struct afs_call *)user_call_ID;
776
777 call->rxcall = NULL;
778 afs_put_call(call);
779}
780
781/*
782 * Notification of an incoming call.
783 */
784static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall,
785 unsigned long user_call_ID)
786{
787 struct afs_call *call = (struct afs_call *)user_call_ID;
788 struct afs_net *net = afs_sock2net(sk);
789
790 call->peer = rxrpc_kernel_get_call_peer(sock: sk->sk_socket, call: call->rxcall);
791 call->server = afs_find_server(peer: call->peer);
792 if (!call->server)
793 trace_afs_cm_no_server(call, srx: rxrpc_kernel_remote_srx(peer: call->peer));
794
795 queue_work(wq: afs_wq, work: &net->charge_preallocation_work);
796}
797
798/*
799 * Grab the operation ID from an incoming cache manager call. The socket
800 * buffer is discarded on error or if we don't yet have sufficient data.
801 */
802static int afs_deliver_cm_op_id(struct afs_call *call)
803{
804 int ret;
805
806 _enter("{%zu}", iov_iter_count(call->iter));
807
808 /* the operation ID forms the first four bytes of the request data */
809 ret = afs_extract_data(call, true);
810 if (ret < 0)
811 return ret;
812
813 call->operation_ID = ntohl(call->tmp);
814 afs_set_call_state(call, from: AFS_CALL_SV_AWAIT_OP_ID, to: AFS_CALL_SV_AWAIT_REQUEST);
815
816 /* ask the cache manager to route the call (it'll change the call type
817 * if successful) */
818 if (!afs_cm_incoming_call(call))
819 return -ENOTSUPP;
820
821 call->security_ix = rxrpc_kernel_query_call_security(call: call->rxcall,
822 service_id: &call->service_id,
823 enctype: &call->enctype);
824
825 trace_afs_cb_call(call);
826 call->work.func = call->type->work;
827
828 /* pass responsibility for the remainder of this message off to the
829 * cache manager op */
830 return call->type->deliver(call);
831}
832
833/*
834 * Advance the AFS call state when an RxRPC service call ends the transmit
835 * phase.
836 */
837static void afs_notify_end_reply_tx(struct sock *sock,
838 struct rxrpc_call *rxcall,
839 unsigned long call_user_ID)
840{
841 struct afs_call *call = (struct afs_call *)call_user_ID;
842
843 afs_set_call_state(call, from: AFS_CALL_SV_REPLYING, to: AFS_CALL_SV_AWAIT_ACK);
844}
845
846/*
847 * send an empty reply
848 */
849void afs_send_empty_reply(struct afs_call *call)
850{
851 struct afs_net *net = call->net;
852 struct msghdr msg;
853
854 _enter("");
855
856 rxrpc_kernel_set_tx_length(net->socket, call->rxcall, 0);
857
858 msg.msg_name = NULL;
859 msg.msg_namelen = 0;
860 iov_iter_kvec(i: &msg.msg_iter, ITER_SOURCE, NULL, nr_segs: 0, count: 0);
861 msg.msg_control = NULL;
862 msg.msg_controllen = 0;
863 msg.msg_flags = 0;
864
865 switch (rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, 0,
866 afs_notify_end_reply_tx)) {
867 case 0:
868 _leave(" [replied]");
869 return;
870
871 case -ENOMEM:
872 _debug("oom");
873 rxrpc_kernel_abort_call(net->socket, call->rxcall,
874 RXGEN_SS_MARSHAL, -ENOMEM,
875 afs_abort_oom);
876 fallthrough;
877 default:
878 _leave(" [error]");
879 return;
880 }
881}
882
883/*
884 * send a simple reply
885 */
886void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
887{
888 struct afs_net *net = call->net;
889 struct msghdr msg;
890 struct kvec iov[1];
891 int n;
892
893 _enter("");
894
895 rxrpc_kernel_set_tx_length(net->socket, call->rxcall, len);
896
897 iov[0].iov_base = (void *) buf;
898 iov[0].iov_len = len;
899 msg.msg_name = NULL;
900 msg.msg_namelen = 0;
901 iov_iter_kvec(i: &msg.msg_iter, ITER_SOURCE, kvec: iov, nr_segs: 1, count: len);
902 msg.msg_control = NULL;
903 msg.msg_controllen = 0;
904 msg.msg_flags = 0;
905
906 n = rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, len,
907 afs_notify_end_reply_tx);
908 if (n >= 0) {
909 /* Success */
910 _leave(" [replied]");
911 return;
912 }
913
914 if (n == -ENOMEM) {
915 _debug("oom");
916 rxrpc_kernel_abort_call(net->socket, call->rxcall,
917 RXGEN_SS_MARSHAL, -ENOMEM,
918 afs_abort_oom);
919 }
920 _leave(" [error]");
921}
922
923/*
924 * Extract a piece of data from the received data socket buffers.
925 */
926int afs_extract_data(struct afs_call *call, bool want_more)
927{
928 struct afs_net *net = call->net;
929 struct iov_iter *iter = call->iter;
930 enum afs_call_state state;
931 u32 remote_abort = 0;
932 int ret;
933
934 _enter("{%s,%zu,%zu},%d",
935 call->type->name, call->iov_len, iov_iter_count(iter), want_more);
936
937 ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter,
938 &call->iov_len, want_more, &remote_abort,
939 &call->service_id);
940 trace_afs_receive_data(call, iter: call->iter, want_more, ret);
941 if (ret == 0 || ret == -EAGAIN)
942 return ret;
943
944 state = READ_ONCE(call->state);
945 if (ret == 1) {
946 switch (state) {
947 case AFS_CALL_CL_AWAIT_REPLY:
948 afs_set_call_state(call, from: state, to: AFS_CALL_CL_PROC_REPLY);
949 break;
950 case AFS_CALL_SV_AWAIT_REQUEST:
951 afs_set_call_state(call, from: state, to: AFS_CALL_SV_REPLYING);
952 break;
953 case AFS_CALL_COMPLETE:
954 kdebug("prem complete %d", call->error);
955 return afs_io_error(call, where: afs_io_error_extract);
956 default:
957 break;
958 }
959 return 0;
960 }
961
962 afs_set_call_complete(call, error: ret, remote_abort);
963 return ret;
964}
965
966/*
967 * Log protocol error production.
968 */
969noinline int afs_protocol_error(struct afs_call *call,
970 enum afs_eproto_cause cause)
971{
972 trace_afs_protocol_error(call, cause);
973 if (call)
974 call->unmarshalling_error = true;
975 return -EBADMSG;
976}
977
978/*
979 * Wake up OOB notification processing.
980 */
981static void afs_rx_notify_oob(struct sock *sk, struct sk_buff *oob)
982{
983 struct afs_net *net = sk->sk_user_data;
984
985 schedule_work(work: &net->rx_oob_work);
986}
987

source code of linux/fs/afs/rxrpc.c