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