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1 | /* Maintain an RxRPC server socket to do AFS communications through | |
2 | * | |
3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. | |
4 | * Written by David Howells (dhowells@redhat.com) | |
5 | * | |
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. | |
10 | */ | |
11 | ||
12 | #include <linux/slab.h> | |
13 | #include <net/sock.h> | |
14 | #include <net/af_rxrpc.h> | |
15 | #include <rxrpc/packet.h> | |
16 | #include "internal.h" | |
17 | #include "afs_cm.h" | |
18 | ||
19 | struct socket *afs_socket; /* my RxRPC socket */ | |
20 | static struct workqueue_struct *afs_async_calls; | |
21 | static struct afs_call *afs_spare_incoming_call; | |
22 | static atomic_t afs_outstanding_calls; | |
23 | ||
24 | static void afs_free_call(struct afs_call *); | |
25 | static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long); | |
26 | static int afs_wait_for_call_to_complete(struct afs_call *); | |
27 | static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long); | |
28 | static int afs_dont_wait_for_call_to_complete(struct afs_call *); | |
29 | static void afs_process_async_call(struct work_struct *); | |
30 | static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long); | |
31 | static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long); | |
32 | static int afs_deliver_cm_op_id(struct afs_call *); | |
33 | ||
34 | /* synchronous call management */ | |
35 | const struct afs_wait_mode afs_sync_call = { | |
36 | .notify_rx = afs_wake_up_call_waiter, | |
37 | .wait = afs_wait_for_call_to_complete, | |
38 | }; | |
39 | ||
40 | /* asynchronous call management */ | |
41 | const struct afs_wait_mode afs_async_call = { | |
42 | .notify_rx = afs_wake_up_async_call, | |
43 | .wait = afs_dont_wait_for_call_to_complete, | |
44 | }; | |
45 | ||
46 | /* asynchronous incoming call management */ | |
47 | static const struct afs_wait_mode afs_async_incoming_call = { | |
48 | .notify_rx = afs_wake_up_async_call, | |
49 | }; | |
50 | ||
51 | /* asynchronous incoming call initial processing */ | |
52 | static const struct afs_call_type afs_RXCMxxxx = { | |
53 | .name = "CB.xxxx", | |
54 | .deliver = afs_deliver_cm_op_id, | |
55 | .abort_to_error = afs_abort_to_error, | |
56 | }; | |
57 | ||
58 | static void afs_charge_preallocation(struct work_struct *); | |
59 | ||
60 | static DECLARE_WORK(afs_charge_preallocation_work, afs_charge_preallocation); | |
61 | ||
62 | static int afs_wait_atomic_t(atomic_t *p) | |
63 | { | |
64 | schedule(); | |
65 | return 0; | |
66 | } | |
67 | ||
68 | /* | |
69 | * open an RxRPC socket and bind it to be a server for callback notifications | |
70 | * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT | |
71 | */ | |
72 | int afs_open_socket(void) | |
73 | { | |
74 | struct sockaddr_rxrpc srx; | |
75 | struct socket *socket; | |
76 | int ret; | |
77 | ||
78 | _enter(""); | |
79 | ||
80 | ret = -ENOMEM; | |
81 | afs_async_calls = alloc_workqueue("kafsd", WQ_MEM_RECLAIM, 0); | |
82 | if (!afs_async_calls) | |
83 | goto error_0; | |
84 | ||
85 | ret = sock_create_kern(&init_net, AF_RXRPC, SOCK_DGRAM, PF_INET, &socket); | |
86 | if (ret < 0) | |
87 | goto error_1; | |
88 | ||
89 | socket->sk->sk_allocation = GFP_NOFS; | |
90 | ||
91 | /* bind the callback manager's address to make this a server socket */ | |
92 | srx.srx_family = AF_RXRPC; | |
93 | srx.srx_service = CM_SERVICE; | |
94 | srx.transport_type = SOCK_DGRAM; | |
95 | srx.transport_len = sizeof(srx.transport.sin); | |
96 | srx.transport.sin.sin_family = AF_INET; | |
97 | srx.transport.sin.sin_port = htons(AFS_CM_PORT); | |
98 | memset(&srx.transport.sin.sin_addr, 0, | |
99 | sizeof(srx.transport.sin.sin_addr)); | |
100 | ||
101 | ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx)); | |
102 | if (ret < 0) | |
103 | goto error_2; | |
104 | ||
105 | rxrpc_kernel_new_call_notification(socket, afs_rx_new_call, | |
106 | afs_rx_discard_new_call); | |
107 | ||
108 | ret = kernel_listen(socket, INT_MAX); | |
109 | if (ret < 0) | |
110 | goto error_2; | |
111 | ||
112 | afs_socket = socket; | |
113 | afs_charge_preallocation(NULL); | |
114 | _leave(" = 0"); | |
115 | return 0; | |
116 | ||
117 | error_2: | |
118 | sock_release(socket); | |
119 | error_1: | |
120 | destroy_workqueue(afs_async_calls); | |
121 | error_0: | |
122 | _leave(" = %d", ret); | |
123 | return ret; | |
124 | } | |
125 | ||
126 | /* | |
127 | * close the RxRPC socket AFS was using | |
128 | */ | |
129 | void afs_close_socket(void) | |
130 | { | |
131 | _enter(""); | |
132 | ||
133 | if (afs_spare_incoming_call) { | |
134 | atomic_inc(&afs_outstanding_calls); | |
135 | afs_free_call(afs_spare_incoming_call); | |
136 | afs_spare_incoming_call = NULL; | |
137 | } | |
138 | ||
139 | _debug("outstanding %u", atomic_read(&afs_outstanding_calls)); | |
140 | wait_on_atomic_t(&afs_outstanding_calls, afs_wait_atomic_t, | |
141 | TASK_UNINTERRUPTIBLE); | |
142 | _debug("no outstanding calls"); | |
143 | ||
144 | flush_workqueue(afs_async_calls); | |
145 | kernel_sock_shutdown(afs_socket, SHUT_RDWR); | |
146 | flush_workqueue(afs_async_calls); | |
147 | sock_release(afs_socket); | |
148 | ||
149 | _debug("dework"); | |
150 | destroy_workqueue(afs_async_calls); | |
151 | _leave(""); | |
152 | } | |
153 | ||
154 | /* | |
155 | * free a call | |
156 | */ | |
157 | static void afs_free_call(struct afs_call *call) | |
158 | { | |
159 | _debug("DONE %p{%s} [%d]", | |
160 | call, call->type->name, atomic_read(&afs_outstanding_calls)); | |
161 | ||
162 | ASSERTCMP(call->rxcall, ==, NULL); | |
163 | ASSERT(!work_pending(&call->async_work)); | |
164 | ASSERT(call->type->name != NULL); | |
165 | ||
166 | kfree(call->request); | |
167 | kfree(call); | |
168 | ||
169 | if (atomic_dec_and_test(&afs_outstanding_calls)) | |
170 | wake_up_atomic_t(&afs_outstanding_calls); | |
171 | } | |
172 | ||
173 | /* | |
174 | * End a call but do not free it | |
175 | */ | |
176 | static void afs_end_call_nofree(struct afs_call *call) | |
177 | { | |
178 | if (call->rxcall) { | |
179 | rxrpc_kernel_end_call(afs_socket, call->rxcall); | |
180 | call->rxcall = NULL; | |
181 | } | |
182 | if (call->type->destructor) | |
183 | call->type->destructor(call); | |
184 | } | |
185 | ||
186 | /* | |
187 | * End a call and free it | |
188 | */ | |
189 | static void afs_end_call(struct afs_call *call) | |
190 | { | |
191 | afs_end_call_nofree(call); | |
192 | afs_free_call(call); | |
193 | } | |
194 | ||
195 | /* | |
196 | * allocate a call with flat request and reply buffers | |
197 | */ | |
198 | struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type, | |
199 | size_t request_size, size_t reply_max) | |
200 | { | |
201 | struct afs_call *call; | |
202 | ||
203 | call = kzalloc(sizeof(*call), GFP_NOFS); | |
204 | if (!call) | |
205 | goto nomem_call; | |
206 | ||
207 | _debug("CALL %p{%s} [%d]", | |
208 | call, type->name, atomic_read(&afs_outstanding_calls)); | |
209 | atomic_inc(&afs_outstanding_calls); | |
210 | ||
211 | call->type = type; | |
212 | call->request_size = request_size; | |
213 | call->reply_max = reply_max; | |
214 | ||
215 | if (request_size) { | |
216 | call->request = kmalloc(request_size, GFP_NOFS); | |
217 | if (!call->request) | |
218 | goto nomem_free; | |
219 | } | |
220 | ||
221 | if (reply_max) { | |
222 | call->buffer = kmalloc(reply_max, GFP_NOFS); | |
223 | if (!call->buffer) | |
224 | goto nomem_free; | |
225 | } | |
226 | ||
227 | init_waitqueue_head(&call->waitq); | |
228 | return call; | |
229 | ||
230 | nomem_free: | |
231 | afs_free_call(call); | |
232 | nomem_call: | |
233 | return NULL; | |
234 | } | |
235 | ||
236 | /* | |
237 | * clean up a call with flat buffer | |
238 | */ | |
239 | void afs_flat_call_destructor(struct afs_call *call) | |
240 | { | |
241 | _enter(""); | |
242 | ||
243 | kfree(call->request); | |
244 | call->request = NULL; | |
245 | kfree(call->buffer); | |
246 | call->buffer = NULL; | |
247 | } | |
248 | ||
249 | /* | |
250 | * attach the data from a bunch of pages on an inode to a call | |
251 | */ | |
252 | static int afs_send_pages(struct afs_call *call, struct msghdr *msg, | |
253 | struct kvec *iov) | |
254 | { | |
255 | struct page *pages[8]; | |
256 | unsigned count, n, loop, offset, to; | |
257 | pgoff_t first = call->first, last = call->last; | |
258 | int ret; | |
259 | ||
260 | _enter(""); | |
261 | ||
262 | offset = call->first_offset; | |
263 | call->first_offset = 0; | |
264 | ||
265 | do { | |
266 | _debug("attach %lx-%lx", first, last); | |
267 | ||
268 | count = last - first + 1; | |
269 | if (count > ARRAY_SIZE(pages)) | |
270 | count = ARRAY_SIZE(pages); | |
271 | n = find_get_pages_contig(call->mapping, first, count, pages); | |
272 | ASSERTCMP(n, ==, count); | |
273 | ||
274 | loop = 0; | |
275 | do { | |
276 | msg->msg_flags = 0; | |
277 | to = PAGE_SIZE; | |
278 | if (first + loop >= last) | |
279 | to = call->last_to; | |
280 | else | |
281 | msg->msg_flags = MSG_MORE; | |
282 | iov->iov_base = kmap(pages[loop]) + offset; | |
283 | iov->iov_len = to - offset; | |
284 | offset = 0; | |
285 | ||
286 | _debug("- range %u-%u%s", | |
287 | offset, to, msg->msg_flags ? " [more]" : ""); | |
288 | iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, | |
289 | iov, 1, to - offset); | |
290 | ||
291 | /* have to change the state *before* sending the last | |
292 | * packet as RxRPC might give us the reply before it | |
293 | * returns from sending the request */ | |
294 | if (first + loop >= last) | |
295 | call->state = AFS_CALL_AWAIT_REPLY; | |
296 | ret = rxrpc_kernel_send_data(afs_socket, call->rxcall, | |
297 | msg, to - offset); | |
298 | kunmap(pages[loop]); | |
299 | if (ret < 0) | |
300 | break; | |
301 | } while (++loop < count); | |
302 | first += count; | |
303 | ||
304 | for (loop = 0; loop < count; loop++) | |
305 | put_page(pages[loop]); | |
306 | if (ret < 0) | |
307 | break; | |
308 | } while (first <= last); | |
309 | ||
310 | _leave(" = %d", ret); | |
311 | return ret; | |
312 | } | |
313 | ||
314 | /* | |
315 | * initiate a call | |
316 | */ | |
317 | int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp, | |
318 | const struct afs_wait_mode *wait_mode) | |
319 | { | |
320 | struct sockaddr_rxrpc srx; | |
321 | struct rxrpc_call *rxcall; | |
322 | struct msghdr msg; | |
323 | struct kvec iov[1]; | |
324 | int ret; | |
325 | ||
326 | _enter("%x,{%d},", addr->s_addr, ntohs(call->port)); | |
327 | ||
328 | ASSERT(call->type != NULL); | |
329 | ASSERT(call->type->name != NULL); | |
330 | ||
331 | _debug("____MAKE %p{%s,%x} [%d]____", | |
332 | call, call->type->name, key_serial(call->key), | |
333 | atomic_read(&afs_outstanding_calls)); | |
334 | ||
335 | call->wait_mode = wait_mode; | |
336 | INIT_WORK(&call->async_work, afs_process_async_call); | |
337 | ||
338 | memset(&srx, 0, sizeof(srx)); | |
339 | srx.srx_family = AF_RXRPC; | |
340 | srx.srx_service = call->service_id; | |
341 | srx.transport_type = SOCK_DGRAM; | |
342 | srx.transport_len = sizeof(srx.transport.sin); | |
343 | srx.transport.sin.sin_family = AF_INET; | |
344 | srx.transport.sin.sin_port = call->port; | |
345 | memcpy(&srx.transport.sin.sin_addr, addr, 4); | |
346 | ||
347 | /* create a call */ | |
348 | rxcall = rxrpc_kernel_begin_call(afs_socket, &srx, call->key, | |
349 | (unsigned long) call, gfp, | |
350 | wait_mode->notify_rx); | |
351 | call->key = NULL; | |
352 | if (IS_ERR(rxcall)) { | |
353 | ret = PTR_ERR(rxcall); | |
354 | goto error_kill_call; | |
355 | } | |
356 | ||
357 | call->rxcall = rxcall; | |
358 | ||
359 | /* send the request */ | |
360 | iov[0].iov_base = call->request; | |
361 | iov[0].iov_len = call->request_size; | |
362 | ||
363 | msg.msg_name = NULL; | |
364 | msg.msg_namelen = 0; | |
365 | iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 1, | |
366 | call->request_size); | |
367 | msg.msg_control = NULL; | |
368 | msg.msg_controllen = 0; | |
369 | msg.msg_flags = (call->send_pages ? MSG_MORE : 0); | |
370 | ||
371 | /* have to change the state *before* sending the last packet as RxRPC | |
372 | * might give us the reply before it returns from sending the | |
373 | * request */ | |
374 | if (!call->send_pages) | |
375 | call->state = AFS_CALL_AWAIT_REPLY; | |
376 | ret = rxrpc_kernel_send_data(afs_socket, rxcall, | |
377 | &msg, call->request_size); | |
378 | if (ret < 0) | |
379 | goto error_do_abort; | |
380 | ||
381 | if (call->send_pages) { | |
382 | ret = afs_send_pages(call, &msg, iov); | |
383 | if (ret < 0) | |
384 | goto error_do_abort; | |
385 | } | |
386 | ||
387 | /* at this point, an async call may no longer exist as it may have | |
388 | * already completed */ | |
389 | return wait_mode->wait(call); | |
390 | ||
391 | error_do_abort: | |
392 | rxrpc_kernel_abort_call(afs_socket, rxcall, RX_USER_ABORT, -ret, "KSD"); | |
393 | error_kill_call: | |
394 | afs_end_call(call); | |
395 | _leave(" = %d", ret); | |
396 | return ret; | |
397 | } | |
398 | ||
399 | /* | |
400 | * deliver messages to a call | |
401 | */ | |
402 | static void afs_deliver_to_call(struct afs_call *call) | |
403 | { | |
404 | u32 abort_code; | |
405 | int ret; | |
406 | ||
407 | _enter("%s", call->type->name); | |
408 | ||
409 | while (call->state == AFS_CALL_AWAIT_REPLY || | |
410 | call->state == AFS_CALL_AWAIT_OP_ID || | |
411 | call->state == AFS_CALL_AWAIT_REQUEST || | |
412 | call->state == AFS_CALL_AWAIT_ACK | |
413 | ) { | |
414 | if (call->state == AFS_CALL_AWAIT_ACK) { | |
415 | size_t offset = 0; | |
416 | ret = rxrpc_kernel_recv_data(afs_socket, call->rxcall, | |
417 | NULL, 0, &offset, false, | |
418 | &call->abort_code); | |
419 | if (ret == -EINPROGRESS || ret == -EAGAIN) | |
420 | return; | |
421 | if (ret == 1) { | |
422 | call->state = AFS_CALL_COMPLETE; | |
423 | goto done; | |
424 | } | |
425 | return; | |
426 | } | |
427 | ||
428 | ret = call->type->deliver(call); | |
429 | switch (ret) { | |
430 | case 0: | |
431 | if (call->state == AFS_CALL_AWAIT_REPLY) | |
432 | call->state = AFS_CALL_COMPLETE; | |
433 | goto done; | |
434 | case -EINPROGRESS: | |
435 | case -EAGAIN: | |
436 | goto out; | |
437 | case -ENOTCONN: | |
438 | abort_code = RX_CALL_DEAD; | |
439 | rxrpc_kernel_abort_call(afs_socket, call->rxcall, | |
440 | abort_code, -ret, "KNC"); | |
441 | goto do_abort; | |
442 | case -ENOTSUPP: | |
443 | abort_code = RX_INVALID_OPERATION; | |
444 | rxrpc_kernel_abort_call(afs_socket, call->rxcall, | |
445 | abort_code, -ret, "KIV"); | |
446 | goto do_abort; | |
447 | case -ENODATA: | |
448 | case -EBADMSG: | |
449 | case -EMSGSIZE: | |
450 | default: | |
451 | abort_code = RXGEN_CC_UNMARSHAL; | |
452 | if (call->state != AFS_CALL_AWAIT_REPLY) | |
453 | abort_code = RXGEN_SS_UNMARSHAL; | |
454 | rxrpc_kernel_abort_call(afs_socket, call->rxcall, | |
455 | abort_code, EBADMSG, "KUM"); | |
456 | goto do_abort; | |
457 | } | |
458 | } | |
459 | ||
460 | done: | |
461 | if (call->state == AFS_CALL_COMPLETE && call->incoming) | |
462 | afs_end_call(call); | |
463 | out: | |
464 | _leave(""); | |
465 | return; | |
466 | ||
467 | do_abort: | |
468 | call->error = ret; | |
469 | call->state = AFS_CALL_COMPLETE; | |
470 | goto done; | |
471 | } | |
472 | ||
473 | /* | |
474 | * wait synchronously for a call to complete | |
475 | */ | |
476 | static int afs_wait_for_call_to_complete(struct afs_call *call) | |
477 | { | |
478 | const char *abort_why; | |
479 | int ret; | |
480 | ||
481 | DECLARE_WAITQUEUE(myself, current); | |
482 | ||
483 | _enter(""); | |
484 | ||
485 | add_wait_queue(&call->waitq, &myself); | |
486 | for (;;) { | |
487 | set_current_state(TASK_INTERRUPTIBLE); | |
488 | ||
489 | /* deliver any messages that are in the queue */ | |
490 | if (call->state < AFS_CALL_COMPLETE && call->need_attention) { | |
491 | call->need_attention = false; | |
492 | __set_current_state(TASK_RUNNING); | |
493 | afs_deliver_to_call(call); | |
494 | continue; | |
495 | } | |
496 | ||
497 | abort_why = "KWC"; | |
498 | ret = call->error; | |
499 | if (call->state == AFS_CALL_COMPLETE) | |
500 | break; | |
501 | abort_why = "KWI"; | |
502 | ret = -EINTR; | |
503 | if (signal_pending(current)) | |
504 | break; | |
505 | schedule(); | |
506 | } | |
507 | ||
508 | remove_wait_queue(&call->waitq, &myself); | |
509 | __set_current_state(TASK_RUNNING); | |
510 | ||
511 | /* kill the call */ | |
512 | if (call->state < AFS_CALL_COMPLETE) { | |
513 | _debug("call incomplete"); | |
514 | rxrpc_kernel_abort_call(afs_socket, call->rxcall, | |
515 | RX_CALL_DEAD, -ret, abort_why); | |
516 | } | |
517 | ||
518 | _debug("call complete"); | |
519 | afs_end_call(call); | |
520 | _leave(" = %d", ret); | |
521 | return ret; | |
522 | } | |
523 | ||
524 | /* | |
525 | * wake up a waiting call | |
526 | */ | |
527 | static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall, | |
528 | unsigned long call_user_ID) | |
529 | { | |
530 | struct afs_call *call = (struct afs_call *)call_user_ID; | |
531 | ||
532 | call->need_attention = true; | |
533 | wake_up(&call->waitq); | |
534 | } | |
535 | ||
536 | /* | |
537 | * wake up an asynchronous call | |
538 | */ | |
539 | static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall, | |
540 | unsigned long call_user_ID) | |
541 | { | |
542 | struct afs_call *call = (struct afs_call *)call_user_ID; | |
543 | ||
544 | call->need_attention = true; | |
545 | queue_work(afs_async_calls, &call->async_work); | |
546 | } | |
547 | ||
548 | /* | |
549 | * put a call into asynchronous mode | |
550 | * - mustn't touch the call descriptor as the call my have completed by the | |
551 | * time we get here | |
552 | */ | |
553 | static int afs_dont_wait_for_call_to_complete(struct afs_call *call) | |
554 | { | |
555 | _enter(""); | |
556 | return -EINPROGRESS; | |
557 | } | |
558 | ||
559 | /* | |
560 | * delete an asynchronous call | |
561 | */ | |
562 | static void afs_delete_async_call(struct work_struct *work) | |
563 | { | |
564 | struct afs_call *call = container_of(work, struct afs_call, async_work); | |
565 | ||
566 | _enter(""); | |
567 | ||
568 | afs_free_call(call); | |
569 | ||
570 | _leave(""); | |
571 | } | |
572 | ||
573 | /* | |
574 | * perform processing on an asynchronous call | |
575 | */ | |
576 | static void afs_process_async_call(struct work_struct *work) | |
577 | { | |
578 | struct afs_call *call = container_of(work, struct afs_call, async_work); | |
579 | ||
580 | _enter(""); | |
581 | ||
582 | if (call->state < AFS_CALL_COMPLETE && call->need_attention) { | |
583 | call->need_attention = false; | |
584 | afs_deliver_to_call(call); | |
585 | } | |
586 | ||
587 | if (call->state == AFS_CALL_COMPLETE && call->wait_mode) { | |
588 | if (call->wait_mode->async_complete) | |
589 | call->wait_mode->async_complete(call->reply, | |
590 | call->error); | |
591 | call->reply = NULL; | |
592 | ||
593 | /* kill the call */ | |
594 | afs_end_call_nofree(call); | |
595 | ||
596 | /* we can't just delete the call because the work item may be | |
597 | * queued */ | |
598 | call->async_work.func = afs_delete_async_call; | |
599 | queue_work(afs_async_calls, &call->async_work); | |
600 | } | |
601 | ||
602 | _leave(""); | |
603 | } | |
604 | ||
605 | static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID) | |
606 | { | |
607 | struct afs_call *call = (struct afs_call *)user_call_ID; | |
608 | ||
609 | call->rxcall = rxcall; | |
610 | } | |
611 | ||
612 | /* | |
613 | * Charge the incoming call preallocation. | |
614 | */ | |
615 | static void afs_charge_preallocation(struct work_struct *work) | |
616 | { | |
617 | struct afs_call *call = afs_spare_incoming_call; | |
618 | ||
619 | for (;;) { | |
620 | if (!call) { | |
621 | call = kzalloc(sizeof(struct afs_call), GFP_KERNEL); | |
622 | if (!call) | |
623 | break; | |
624 | ||
625 | INIT_WORK(&call->async_work, afs_process_async_call); | |
626 | call->wait_mode = &afs_async_incoming_call; | |
627 | call->type = &afs_RXCMxxxx; | |
628 | init_waitqueue_head(&call->waitq); | |
629 | call->state = AFS_CALL_AWAIT_OP_ID; | |
630 | } | |
631 | ||
632 | if (rxrpc_kernel_charge_accept(afs_socket, | |
633 | afs_wake_up_async_call, | |
634 | afs_rx_attach, | |
635 | (unsigned long)call, | |
636 | GFP_KERNEL) < 0) | |
637 | break; | |
638 | call = NULL; | |
639 | } | |
640 | afs_spare_incoming_call = call; | |
641 | } | |
642 | ||
643 | /* | |
644 | * Discard a preallocated call when a socket is shut down. | |
645 | */ | |
646 | static void afs_rx_discard_new_call(struct rxrpc_call *rxcall, | |
647 | unsigned long user_call_ID) | |
648 | { | |
649 | struct afs_call *call = (struct afs_call *)user_call_ID; | |
650 | ||
651 | atomic_inc(&afs_outstanding_calls); | |
652 | call->rxcall = NULL; | |
653 | afs_free_call(call); | |
654 | } | |
655 | ||
656 | /* | |
657 | * Notification of an incoming call. | |
658 | */ | |
659 | static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall, | |
660 | unsigned long user_call_ID) | |
661 | { | |
662 | atomic_inc(&afs_outstanding_calls); | |
663 | queue_work(afs_wq, &afs_charge_preallocation_work); | |
664 | } | |
665 | ||
666 | /* | |
667 | * Grab the operation ID from an incoming cache manager call. The socket | |
668 | * buffer is discarded on error or if we don't yet have sufficient data. | |
669 | */ | |
670 | static int afs_deliver_cm_op_id(struct afs_call *call) | |
671 | { | |
672 | int ret; | |
673 | ||
674 | _enter("{%zu}", call->offset); | |
675 | ||
676 | ASSERTCMP(call->offset, <, 4); | |
677 | ||
678 | /* the operation ID forms the first four bytes of the request data */ | |
679 | ret = afs_extract_data(call, &call->operation_ID, 4, true); | |
680 | if (ret < 0) | |
681 | return ret; | |
682 | ||
683 | call->state = AFS_CALL_AWAIT_REQUEST; | |
684 | call->offset = 0; | |
685 | ||
686 | /* ask the cache manager to route the call (it'll change the call type | |
687 | * if successful) */ | |
688 | if (!afs_cm_incoming_call(call)) | |
689 | return -ENOTSUPP; | |
690 | ||
691 | /* pass responsibility for the remainer of this message off to the | |
692 | * cache manager op */ | |
693 | return call->type->deliver(call); | |
694 | } | |
695 | ||
696 | /* | |
697 | * send an empty reply | |
698 | */ | |
699 | void afs_send_empty_reply(struct afs_call *call) | |
700 | { | |
701 | struct msghdr msg; | |
702 | ||
703 | _enter(""); | |
704 | ||
705 | msg.msg_name = NULL; | |
706 | msg.msg_namelen = 0; | |
707 | iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, NULL, 0, 0); | |
708 | msg.msg_control = NULL; | |
709 | msg.msg_controllen = 0; | |
710 | msg.msg_flags = 0; | |
711 | ||
712 | call->state = AFS_CALL_AWAIT_ACK; | |
713 | switch (rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, 0)) { | |
714 | case 0: | |
715 | _leave(" [replied]"); | |
716 | return; | |
717 | ||
718 | case -ENOMEM: | |
719 | _debug("oom"); | |
720 | rxrpc_kernel_abort_call(afs_socket, call->rxcall, | |
721 | RX_USER_ABORT, ENOMEM, "KOO"); | |
722 | default: | |
723 | afs_end_call(call); | |
724 | _leave(" [error]"); | |
725 | return; | |
726 | } | |
727 | } | |
728 | ||
729 | /* | |
730 | * send a simple reply | |
731 | */ | |
732 | void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) | |
733 | { | |
734 | struct msghdr msg; | |
735 | struct kvec iov[1]; | |
736 | int n; | |
737 | ||
738 | _enter(""); | |
739 | ||
740 | iov[0].iov_base = (void *) buf; | |
741 | iov[0].iov_len = len; | |
742 | msg.msg_name = NULL; | |
743 | msg.msg_namelen = 0; | |
744 | iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iov, 1, len); | |
745 | msg.msg_control = NULL; | |
746 | msg.msg_controllen = 0; | |
747 | msg.msg_flags = 0; | |
748 | ||
749 | call->state = AFS_CALL_AWAIT_ACK; | |
750 | n = rxrpc_kernel_send_data(afs_socket, call->rxcall, &msg, len); | |
751 | if (n >= 0) { | |
752 | /* Success */ | |
753 | _leave(" [replied]"); | |
754 | return; | |
755 | } | |
756 | ||
757 | if (n == -ENOMEM) { | |
758 | _debug("oom"); | |
759 | rxrpc_kernel_abort_call(afs_socket, call->rxcall, | |
760 | RX_USER_ABORT, ENOMEM, "KOO"); | |
761 | } | |
762 | afs_end_call(call); | |
763 | _leave(" [error]"); | |
764 | } | |
765 | ||
766 | /* | |
767 | * Extract a piece of data from the received data socket buffers. | |
768 | */ | |
769 | int afs_extract_data(struct afs_call *call, void *buf, size_t count, | |
770 | bool want_more) | |
771 | { | |
772 | int ret; | |
773 | ||
774 | _enter("{%s,%zu},,%zu,%d", | |
775 | call->type->name, call->offset, count, want_more); | |
776 | ||
777 | ASSERTCMP(call->offset, <=, count); | |
778 | ||
779 | ret = rxrpc_kernel_recv_data(afs_socket, call->rxcall, | |
780 | buf, count, &call->offset, | |
781 | want_more, &call->abort_code); | |
782 | if (ret == 0 || ret == -EAGAIN) | |
783 | return ret; | |
784 | ||
785 | if (ret == 1) { | |
786 | switch (call->state) { | |
787 | case AFS_CALL_AWAIT_REPLY: | |
788 | call->state = AFS_CALL_COMPLETE; | |
789 | break; | |
790 | case AFS_CALL_AWAIT_REQUEST: | |
791 | call->state = AFS_CALL_REPLYING; | |
792 | break; | |
793 | default: | |
794 | break; | |
795 | } | |
796 | return 0; | |
797 | } | |
798 | ||
799 | if (ret == -ECONNABORTED) | |
800 | call->error = call->type->abort_to_error(call->abort_code); | |
801 | else | |
802 | call->error = ret; | |
803 | call->state = AFS_CALL_COMPLETE; | |
804 | return ret; | |
805 | } |