xref: /linux/fs/afs/cmservice.c (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* AFS Cache Manager Service
3  *
4  * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/slab.h>
11 #include <linux/sched.h>
12 #include <linux/ip.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 static int afs_deliver_cb_init_call_back_state(struct afs_call *);
20 static int afs_deliver_cb_init_call_back_state3(struct afs_call *);
21 static int afs_deliver_cb_probe(struct afs_call *);
22 static int afs_deliver_cb_callback(struct afs_call *);
23 static int afs_deliver_cb_probe_uuid(struct afs_call *);
24 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
25 static void afs_cm_destructor(struct afs_call *);
26 static void SRXAFSCB_CallBack(struct work_struct *);
27 static void SRXAFSCB_InitCallBackState(struct work_struct *);
28 static void SRXAFSCB_Probe(struct work_struct *);
29 static void SRXAFSCB_ProbeUuid(struct work_struct *);
30 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
31 
32 static int afs_deliver_yfs_cb_callback(struct afs_call *);
33 
34 /*
35  * CB.CallBack operation type
36  */
37 static const struct afs_call_type afs_SRXCBCallBack = {
38 	.name		= "CB.CallBack",
39 	.deliver	= afs_deliver_cb_callback,
40 	.destructor	= afs_cm_destructor,
41 	.work		= SRXAFSCB_CallBack,
42 };
43 
44 /*
45  * CB.InitCallBackState operation type
46  */
47 static const struct afs_call_type afs_SRXCBInitCallBackState = {
48 	.name		= "CB.InitCallBackState",
49 	.deliver	= afs_deliver_cb_init_call_back_state,
50 	.destructor	= afs_cm_destructor,
51 	.work		= SRXAFSCB_InitCallBackState,
52 };
53 
54 /*
55  * CB.InitCallBackState3 operation type
56  */
57 static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
58 	.name		= "CB.InitCallBackState3",
59 	.deliver	= afs_deliver_cb_init_call_back_state3,
60 	.destructor	= afs_cm_destructor,
61 	.work		= SRXAFSCB_InitCallBackState,
62 };
63 
64 /*
65  * CB.Probe operation type
66  */
67 static const struct afs_call_type afs_SRXCBProbe = {
68 	.name		= "CB.Probe",
69 	.deliver	= afs_deliver_cb_probe,
70 	.destructor	= afs_cm_destructor,
71 	.work		= SRXAFSCB_Probe,
72 };
73 
74 /*
75  * CB.ProbeUuid operation type
76  */
77 static const struct afs_call_type afs_SRXCBProbeUuid = {
78 	.name		= "CB.ProbeUuid",
79 	.deliver	= afs_deliver_cb_probe_uuid,
80 	.destructor	= afs_cm_destructor,
81 	.work		= SRXAFSCB_ProbeUuid,
82 };
83 
84 /*
85  * CB.TellMeAboutYourself operation type
86  */
87 static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
88 	.name		= "CB.TellMeAboutYourself",
89 	.deliver	= afs_deliver_cb_tell_me_about_yourself,
90 	.destructor	= afs_cm_destructor,
91 	.work		= SRXAFSCB_TellMeAboutYourself,
92 };
93 
94 /*
95  * YFS CB.CallBack operation type
96  */
97 static const struct afs_call_type afs_SRXYFSCB_CallBack = {
98 	.name		= "YFSCB.CallBack",
99 	.deliver	= afs_deliver_yfs_cb_callback,
100 	.destructor	= afs_cm_destructor,
101 	.work		= SRXAFSCB_CallBack,
102 };
103 
104 /*
105  * route an incoming cache manager call
106  * - return T if supported, F if not
107  */
108 bool afs_cm_incoming_call(struct afs_call *call)
109 {
110 	_enter("{%u, CB.OP %u}", call->service_id, call->operation_ID);
111 
112 	switch (call->operation_ID) {
113 	case CBCallBack:
114 		call->type = &afs_SRXCBCallBack;
115 		return true;
116 	case CBInitCallBackState:
117 		call->type = &afs_SRXCBInitCallBackState;
118 		return true;
119 	case CBInitCallBackState3:
120 		call->type = &afs_SRXCBInitCallBackState3;
121 		return true;
122 	case CBProbe:
123 		call->type = &afs_SRXCBProbe;
124 		return true;
125 	case CBProbeUuid:
126 		call->type = &afs_SRXCBProbeUuid;
127 		return true;
128 	case CBTellMeAboutYourself:
129 		call->type = &afs_SRXCBTellMeAboutYourself;
130 		return true;
131 	case YFSCBCallBack:
132 		if (call->service_id != YFS_CM_SERVICE)
133 			return false;
134 		call->type = &afs_SRXYFSCB_CallBack;
135 		return true;
136 	default:
137 		return false;
138 	}
139 }
140 
141 /*
142  * Clean up a cache manager call.
143  */
144 static void afs_cm_destructor(struct afs_call *call)
145 {
146 	kfree(call->buffer);
147 	call->buffer = NULL;
148 }
149 
150 /*
151  * Abort a service call from within an action function.
152  */
153 static void afs_abort_service_call(struct afs_call *call, u32 abort_code, int error,
154 				   enum rxrpc_abort_reason why)
155 {
156 	rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
157 				abort_code, error, why);
158 	afs_set_call_complete(call, error, 0);
159 }
160 
161 /*
162  * The server supplied a list of callbacks that it wanted to break.
163  */
164 static void SRXAFSCB_CallBack(struct work_struct *work)
165 {
166 	struct afs_call *call = container_of(work, struct afs_call, work);
167 
168 	_enter("");
169 
170 	/* We need to break the callbacks before sending the reply as the
171 	 * server holds up change visibility till it receives our reply so as
172 	 * to maintain cache coherency.
173 	 */
174 	if (call->server) {
175 		trace_afs_server(call->server->debug_id,
176 				 refcount_read(&call->server->ref),
177 				 atomic_read(&call->server->active),
178 				 afs_server_trace_callback);
179 		afs_break_callbacks(call->server, call->count, call->request);
180 	}
181 
182 	afs_send_empty_reply(call);
183 	afs_put_call(call);
184 	_leave("");
185 }
186 
187 /*
188  * deliver request data to a CB.CallBack call
189  */
190 static int afs_deliver_cb_callback(struct afs_call *call)
191 {
192 	struct afs_callback_break *cb;
193 	__be32 *bp;
194 	int ret, loop;
195 
196 	_enter("{%u}", call->unmarshall);
197 
198 	switch (call->unmarshall) {
199 	case 0:
200 		afs_extract_to_tmp(call);
201 		call->unmarshall++;
202 
203 		/* extract the FID array and its count in two steps */
204 		fallthrough;
205 	case 1:
206 		_debug("extract FID count");
207 		ret = afs_extract_data(call, true);
208 		if (ret < 0)
209 			return ret;
210 
211 		call->count = ntohl(call->tmp);
212 		_debug("FID count: %u", call->count);
213 		if (call->count > AFSCBMAX)
214 			return afs_protocol_error(call, afs_eproto_cb_fid_count);
215 
216 		call->buffer = kmalloc(array3_size(call->count, 3, 4),
217 				       GFP_KERNEL);
218 		if (!call->buffer)
219 			return -ENOMEM;
220 		afs_extract_to_buf(call, call->count * 3 * 4);
221 		call->unmarshall++;
222 
223 		fallthrough;
224 	case 2:
225 		_debug("extract FID array");
226 		ret = afs_extract_data(call, true);
227 		if (ret < 0)
228 			return ret;
229 
230 		_debug("unmarshall FID array");
231 		call->request = kzalloc_objs(struct afs_callback_break,
232 					     call->count, GFP_KERNEL);
233 		if (!call->request)
234 			return -ENOMEM;
235 
236 		cb = call->request;
237 		bp = call->buffer;
238 		for (loop = call->count; loop > 0; loop--, cb++) {
239 			cb->fid.vid	= ntohl(*bp++);
240 			cb->fid.vnode	= ntohl(*bp++);
241 			cb->fid.unique	= ntohl(*bp++);
242 		}
243 
244 		afs_extract_to_tmp(call);
245 		call->unmarshall++;
246 
247 		/* extract the callback array and its count in two steps */
248 		fallthrough;
249 	case 3:
250 		_debug("extract CB count");
251 		ret = afs_extract_data(call, true);
252 		if (ret < 0)
253 			return ret;
254 
255 		call->count2 = ntohl(call->tmp);
256 		_debug("CB count: %u", call->count2);
257 		if (call->count2 != call->count && call->count2 != 0)
258 			return afs_protocol_error(call, afs_eproto_cb_count);
259 		call->iter = &call->def_iter;
260 		iov_iter_discard(&call->def_iter, ITER_DEST, call->count2 * 3 * 4);
261 		call->unmarshall++;
262 
263 		fallthrough;
264 	case 4:
265 		_debug("extract discard %zu/%u",
266 		       iov_iter_count(call->iter), call->count2 * 3 * 4);
267 
268 		ret = afs_extract_data(call, false);
269 		if (ret < 0)
270 			return ret;
271 
272 		call->unmarshall++;
273 		fallthrough;
274 
275 	case 5:
276 		break;
277 	}
278 
279 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
280 		return afs_io_error(call, afs_io_error_cm_reply);
281 	return 0;
282 }
283 
284 /*
285  * allow the fileserver to request callback state (re-)initialisation
286  */
287 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
288 {
289 	struct afs_call *call = container_of(work, struct afs_call, work);
290 
291 	_enter("{%p}", call->server);
292 
293 	if (call->server)
294 		afs_init_callback_state(call->server);
295 	afs_send_empty_reply(call);
296 	afs_put_call(call);
297 	_leave("");
298 }
299 
300 /*
301  * deliver request data to a CB.InitCallBackState call
302  */
303 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
304 {
305 	_enter("");
306 
307 	afs_extract_discard(call, 0);
308 	return afs_extract_data(call, false);
309 }
310 
311 /*
312  * deliver request data to a CB.InitCallBackState3 call
313  */
314 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
315 {
316 	struct afs_uuid *r;
317 	unsigned loop;
318 	__be32 *b;
319 	int ret;
320 
321 	_enter("{%u}", call->unmarshall);
322 
323 	switch (call->unmarshall) {
324 	case 0:
325 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
326 		if (!call->buffer)
327 			return -ENOMEM;
328 		afs_extract_to_buf(call, 11 * sizeof(__be32));
329 		call->unmarshall++;
330 
331 		fallthrough;
332 	case 1:
333 		_debug("extract UUID");
334 		ret = afs_extract_data(call, false);
335 		switch (ret) {
336 		case 0:		break;
337 		case -EAGAIN:	return 0;
338 		default:	return ret;
339 		}
340 
341 		_debug("unmarshall UUID");
342 		call->request = kmalloc_obj(struct afs_uuid, GFP_KERNEL);
343 		if (!call->request)
344 			return -ENOMEM;
345 
346 		b = call->buffer;
347 		r = call->request;
348 		r->time_low			= b[0];
349 		r->time_mid			= htons(ntohl(b[1]));
350 		r->time_hi_and_version		= htons(ntohl(b[2]));
351 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
352 		r->clock_seq_low		= ntohl(b[4]);
353 
354 		for (loop = 0; loop < 6; loop++)
355 			r->node[loop] = ntohl(b[loop + 5]);
356 
357 		call->unmarshall++;
358 		fallthrough;
359 
360 	case 2:
361 		break;
362 	}
363 
364 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
365 		return afs_io_error(call, afs_io_error_cm_reply);
366 
367 	if (memcmp(call->request, &call->server->_uuid, sizeof(call->server->_uuid)) != 0) {
368 		pr_notice("Callback UUID does not match fileserver UUID\n");
369 		trace_afs_cm_no_server_u(call, call->request);
370 		return 0;
371 	}
372 
373 	return 0;
374 }
375 
376 /*
377  * allow the fileserver to see if the cache manager is still alive
378  */
379 static void SRXAFSCB_Probe(struct work_struct *work)
380 {
381 	struct afs_call *call = container_of(work, struct afs_call, work);
382 
383 	_enter("");
384 	afs_send_empty_reply(call);
385 	afs_put_call(call);
386 	_leave("");
387 }
388 
389 /*
390  * deliver request data to a CB.Probe call
391  */
392 static int afs_deliver_cb_probe(struct afs_call *call)
393 {
394 	int ret;
395 
396 	_enter("");
397 
398 	afs_extract_discard(call, 0);
399 	ret = afs_extract_data(call, false);
400 	if (ret < 0)
401 		return ret;
402 
403 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
404 		return afs_io_error(call, afs_io_error_cm_reply);
405 	return 0;
406 }
407 
408 /*
409  * Allow the fileserver to quickly find out if the cache manager has been
410  * rebooted.
411  */
412 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
413 {
414 	struct afs_call *call = container_of(work, struct afs_call, work);
415 	struct afs_uuid *r = call->request;
416 
417 	_enter("");
418 
419 	if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
420 		afs_send_empty_reply(call);
421 	else
422 		afs_abort_service_call(call, 1, 1, afs_abort_probeuuid_negative);
423 
424 	afs_put_call(call);
425 	_leave("");
426 }
427 
428 /*
429  * deliver request data to a CB.ProbeUuid call
430  */
431 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
432 {
433 	struct afs_uuid *r;
434 	unsigned loop;
435 	__be32 *b;
436 	int ret;
437 
438 	_enter("{%u}", call->unmarshall);
439 
440 	switch (call->unmarshall) {
441 	case 0:
442 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
443 		if (!call->buffer)
444 			return -ENOMEM;
445 		afs_extract_to_buf(call, 11 * sizeof(__be32));
446 		call->unmarshall++;
447 
448 		fallthrough;
449 	case 1:
450 		_debug("extract UUID");
451 		ret = afs_extract_data(call, false);
452 		switch (ret) {
453 		case 0:		break;
454 		case -EAGAIN:	return 0;
455 		default:	return ret;
456 		}
457 
458 		_debug("unmarshall UUID");
459 		call->request = kmalloc_obj(struct afs_uuid, GFP_KERNEL);
460 		if (!call->request)
461 			return -ENOMEM;
462 
463 		b = call->buffer;
464 		r = call->request;
465 		r->time_low			= b[0];
466 		r->time_mid			= htons(ntohl(b[1]));
467 		r->time_hi_and_version		= htons(ntohl(b[2]));
468 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
469 		r->clock_seq_low		= ntohl(b[4]);
470 
471 		for (loop = 0; loop < 6; loop++)
472 			r->node[loop] = ntohl(b[loop + 5]);
473 
474 		call->unmarshall++;
475 		fallthrough;
476 
477 	case 2:
478 		break;
479 	}
480 
481 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
482 		return afs_io_error(call, afs_io_error_cm_reply);
483 	return 0;
484 }
485 
486 /*
487  * allow the fileserver to ask about the cache manager's capabilities
488  */
489 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
490 {
491 	struct afs_call *call = container_of(work, struct afs_call, work);
492 	int loop;
493 
494 	struct {
495 		struct /* InterfaceAddr */ {
496 			__be32 nifs;
497 			__be32 uuid[11];
498 			__be32 ifaddr[32];
499 			__be32 netmask[32];
500 			__be32 mtu[32];
501 		} ia;
502 		struct /* Capabilities */ {
503 			__be32 capcount;
504 			__be32 caps[1];
505 		} cap;
506 	} reply;
507 
508 	_enter("");
509 
510 	memset(&reply, 0, sizeof(reply));
511 
512 	reply.ia.uuid[0] = call->net->uuid.time_low;
513 	reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
514 	reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
515 	reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
516 	reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
517 	for (loop = 0; loop < 6; loop++)
518 		reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
519 
520 	reply.cap.capcount = htonl(1);
521 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
522 	afs_send_simple_reply(call, &reply, sizeof(reply));
523 	afs_put_call(call);
524 	_leave("");
525 }
526 
527 /*
528  * deliver request data to a CB.TellMeAboutYourself call
529  */
530 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
531 {
532 	int ret;
533 
534 	_enter("");
535 
536 	afs_extract_discard(call, 0);
537 	ret = afs_extract_data(call, false);
538 	if (ret < 0)
539 		return ret;
540 
541 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
542 		return afs_io_error(call, afs_io_error_cm_reply);
543 	return 0;
544 }
545 
546 /*
547  * deliver request data to a YFS CB.CallBack call
548  */
549 static int afs_deliver_yfs_cb_callback(struct afs_call *call)
550 {
551 	struct afs_callback_break *cb;
552 	struct yfs_xdr_YFSFid *bp;
553 	size_t size;
554 	int ret, loop;
555 
556 	_enter("{%u}", call->unmarshall);
557 
558 	switch (call->unmarshall) {
559 	case 0:
560 		afs_extract_to_tmp(call);
561 		call->unmarshall++;
562 
563 		/* extract the FID array and its count in two steps */
564 		fallthrough;
565 	case 1:
566 		_debug("extract FID count");
567 		ret = afs_extract_data(call, true);
568 		if (ret < 0)
569 			return ret;
570 
571 		call->count = ntohl(call->tmp);
572 		_debug("FID count: %u", call->count);
573 		if (call->count > YFSCBMAX)
574 			return afs_protocol_error(call, afs_eproto_cb_fid_count);
575 
576 		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
577 		call->buffer = kmalloc(size, GFP_KERNEL);
578 		if (!call->buffer)
579 			return -ENOMEM;
580 		afs_extract_to_buf(call, size);
581 		call->unmarshall++;
582 
583 		fallthrough;
584 	case 2:
585 		_debug("extract FID array");
586 		ret = afs_extract_data(call, false);
587 		if (ret < 0)
588 			return ret;
589 
590 		_debug("unmarshall FID array");
591 		call->request = kzalloc_objs(struct afs_callback_break,
592 					     call->count, GFP_KERNEL);
593 		if (!call->request)
594 			return -ENOMEM;
595 
596 		cb = call->request;
597 		bp = call->buffer;
598 		for (loop = call->count; loop > 0; loop--, cb++) {
599 			cb->fid.vid	= xdr_to_u64(bp->volume);
600 			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
601 			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
602 			cb->fid.unique	= ntohl(bp->vnode.unique);
603 			bp++;
604 		}
605 
606 		afs_extract_to_tmp(call);
607 		call->unmarshall++;
608 		fallthrough;
609 
610 	case 3:
611 		break;
612 	}
613 
614 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
615 		return afs_io_error(call, afs_io_error_cm_reply);
616 	return 0;
617 }
618