xref: /linux/fs/afs/cmservice.c (revision 2dbc0838bcf24ca59cabc3130cf3b1d6809cdcd4)
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 
17 static int afs_deliver_cb_init_call_back_state(struct afs_call *);
18 static int afs_deliver_cb_init_call_back_state3(struct afs_call *);
19 static int afs_deliver_cb_probe(struct afs_call *);
20 static int afs_deliver_cb_callback(struct afs_call *);
21 static int afs_deliver_cb_probe_uuid(struct afs_call *);
22 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
23 static void afs_cm_destructor(struct afs_call *);
24 static void SRXAFSCB_CallBack(struct work_struct *);
25 static void SRXAFSCB_InitCallBackState(struct work_struct *);
26 static void SRXAFSCB_Probe(struct work_struct *);
27 static void SRXAFSCB_ProbeUuid(struct work_struct *);
28 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
29 
30 static int afs_deliver_yfs_cb_callback(struct afs_call *);
31 
32 #define CM_NAME(name) \
33 	char afs_SRXCB##name##_name[] __tracepoint_string =	\
34 		"CB." #name
35 
36 /*
37  * CB.CallBack operation type
38  */
39 static CM_NAME(CallBack);
40 static const struct afs_call_type afs_SRXCBCallBack = {
41 	.name		= afs_SRXCBCallBack_name,
42 	.deliver	= afs_deliver_cb_callback,
43 	.destructor	= afs_cm_destructor,
44 	.work		= SRXAFSCB_CallBack,
45 };
46 
47 /*
48  * CB.InitCallBackState operation type
49  */
50 static CM_NAME(InitCallBackState);
51 static const struct afs_call_type afs_SRXCBInitCallBackState = {
52 	.name		= afs_SRXCBInitCallBackState_name,
53 	.deliver	= afs_deliver_cb_init_call_back_state,
54 	.destructor	= afs_cm_destructor,
55 	.work		= SRXAFSCB_InitCallBackState,
56 };
57 
58 /*
59  * CB.InitCallBackState3 operation type
60  */
61 static CM_NAME(InitCallBackState3);
62 static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
63 	.name		= afs_SRXCBInitCallBackState3_name,
64 	.deliver	= afs_deliver_cb_init_call_back_state3,
65 	.destructor	= afs_cm_destructor,
66 	.work		= SRXAFSCB_InitCallBackState,
67 };
68 
69 /*
70  * CB.Probe operation type
71  */
72 static CM_NAME(Probe);
73 static const struct afs_call_type afs_SRXCBProbe = {
74 	.name		= afs_SRXCBProbe_name,
75 	.deliver	= afs_deliver_cb_probe,
76 	.destructor	= afs_cm_destructor,
77 	.work		= SRXAFSCB_Probe,
78 };
79 
80 /*
81  * CB.ProbeUuid operation type
82  */
83 static CM_NAME(ProbeUuid);
84 static const struct afs_call_type afs_SRXCBProbeUuid = {
85 	.name		= afs_SRXCBProbeUuid_name,
86 	.deliver	= afs_deliver_cb_probe_uuid,
87 	.destructor	= afs_cm_destructor,
88 	.work		= SRXAFSCB_ProbeUuid,
89 };
90 
91 /*
92  * CB.TellMeAboutYourself operation type
93  */
94 static CM_NAME(TellMeAboutYourself);
95 static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
96 	.name		= afs_SRXCBTellMeAboutYourself_name,
97 	.deliver	= afs_deliver_cb_tell_me_about_yourself,
98 	.destructor	= afs_cm_destructor,
99 	.work		= SRXAFSCB_TellMeAboutYourself,
100 };
101 
102 /*
103  * YFS CB.CallBack operation type
104  */
105 static CM_NAME(YFS_CallBack);
106 static const struct afs_call_type afs_SRXYFSCB_CallBack = {
107 	.name		= afs_SRXCBYFS_CallBack_name,
108 	.deliver	= afs_deliver_yfs_cb_callback,
109 	.destructor	= afs_cm_destructor,
110 	.work		= SRXAFSCB_CallBack,
111 };
112 
113 /*
114  * route an incoming cache manager call
115  * - return T if supported, F if not
116  */
117 bool afs_cm_incoming_call(struct afs_call *call)
118 {
119 	_enter("{%u, CB.OP %u}", call->service_id, call->operation_ID);
120 
121 	call->epoch = rxrpc_kernel_get_epoch(call->net->socket, call->rxcall);
122 
123 	switch (call->operation_ID) {
124 	case CBCallBack:
125 		call->type = &afs_SRXCBCallBack;
126 		return true;
127 	case CBInitCallBackState:
128 		call->type = &afs_SRXCBInitCallBackState;
129 		return true;
130 	case CBInitCallBackState3:
131 		call->type = &afs_SRXCBInitCallBackState3;
132 		return true;
133 	case CBProbe:
134 		call->type = &afs_SRXCBProbe;
135 		return true;
136 	case CBProbeUuid:
137 		call->type = &afs_SRXCBProbeUuid;
138 		return true;
139 	case CBTellMeAboutYourself:
140 		call->type = &afs_SRXCBTellMeAboutYourself;
141 		return true;
142 	case YFSCBCallBack:
143 		if (call->service_id != YFS_CM_SERVICE)
144 			return false;
145 		call->type = &afs_SRXYFSCB_CallBack;
146 		return true;
147 	default:
148 		return false;
149 	}
150 }
151 
152 /*
153  * Record a probe to the cache manager from a server.
154  */
155 static int afs_record_cm_probe(struct afs_call *call, struct afs_server *server)
156 {
157 	_enter("");
158 
159 	if (test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags) &&
160 	    !test_bit(AFS_SERVER_FL_PROBING, &server->flags)) {
161 		if (server->cm_epoch == call->epoch)
162 			return 0;
163 
164 		if (!server->probe.said_rebooted) {
165 			pr_notice("kAFS: FS rebooted %pU\n", &server->uuid);
166 			server->probe.said_rebooted = true;
167 		}
168 	}
169 
170 	spin_lock(&server->probe_lock);
171 
172 	if (!test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags)) {
173 		server->cm_epoch = call->epoch;
174 		server->probe.cm_epoch = call->epoch;
175 		goto out;
176 	}
177 
178 	if (server->probe.cm_probed &&
179 	    call->epoch != server->probe.cm_epoch &&
180 	    !server->probe.said_inconsistent) {
181 		pr_notice("kAFS: FS endpoints inconsistent %pU\n",
182 			  &server->uuid);
183 		server->probe.said_inconsistent = true;
184 	}
185 
186 	if (!server->probe.cm_probed || call->epoch == server->cm_epoch)
187 		server->probe.cm_epoch = server->cm_epoch;
188 
189 out:
190 	server->probe.cm_probed = true;
191 	spin_unlock(&server->probe_lock);
192 	return 0;
193 }
194 
195 /*
196  * Find the server record by peer address and record a probe to the cache
197  * manager from a server.
198  */
199 static int afs_find_cm_server_by_peer(struct afs_call *call)
200 {
201 	struct sockaddr_rxrpc srx;
202 	struct afs_server *server;
203 
204 	rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
205 
206 	server = afs_find_server(call->net, &srx);
207 	if (!server) {
208 		trace_afs_cm_no_server(call, &srx);
209 		return 0;
210 	}
211 
212 	call->server = server;
213 	return afs_record_cm_probe(call, server);
214 }
215 
216 /*
217  * Find the server record by server UUID and record a probe to the cache
218  * manager from a server.
219  */
220 static int afs_find_cm_server_by_uuid(struct afs_call *call,
221 				      struct afs_uuid *uuid)
222 {
223 	struct afs_server *server;
224 
225 	rcu_read_lock();
226 	server = afs_find_server_by_uuid(call->net, call->request);
227 	rcu_read_unlock();
228 	if (!server) {
229 		trace_afs_cm_no_server_u(call, call->request);
230 		return 0;
231 	}
232 
233 	call->server = server;
234 	return afs_record_cm_probe(call, server);
235 }
236 
237 /*
238  * Clean up a cache manager call.
239  */
240 static void afs_cm_destructor(struct afs_call *call)
241 {
242 	kfree(call->buffer);
243 	call->buffer = NULL;
244 }
245 
246 /*
247  * The server supplied a list of callbacks that it wanted to break.
248  */
249 static void SRXAFSCB_CallBack(struct work_struct *work)
250 {
251 	struct afs_call *call = container_of(work, struct afs_call, work);
252 
253 	_enter("");
254 
255 	/* We need to break the callbacks before sending the reply as the
256 	 * server holds up change visibility till it receives our reply so as
257 	 * to maintain cache coherency.
258 	 */
259 	if (call->server) {
260 		trace_afs_server(call->server, atomic_read(&call->server->usage),
261 				 afs_server_trace_callback);
262 		afs_break_callbacks(call->server, call->count, call->request);
263 	}
264 
265 	afs_send_empty_reply(call);
266 	afs_put_call(call);
267 	_leave("");
268 }
269 
270 /*
271  * deliver request data to a CB.CallBack call
272  */
273 static int afs_deliver_cb_callback(struct afs_call *call)
274 {
275 	struct afs_callback_break *cb;
276 	__be32 *bp;
277 	int ret, loop;
278 
279 	_enter("{%u}", call->unmarshall);
280 
281 	switch (call->unmarshall) {
282 	case 0:
283 		afs_extract_to_tmp(call);
284 		call->unmarshall++;
285 
286 		/* extract the FID array and its count in two steps */
287 		/* fall through */
288 	case 1:
289 		_debug("extract FID count");
290 		ret = afs_extract_data(call, true);
291 		if (ret < 0)
292 			return ret;
293 
294 		call->count = ntohl(call->tmp);
295 		_debug("FID count: %u", call->count);
296 		if (call->count > AFSCBMAX)
297 			return afs_protocol_error(call, -EBADMSG,
298 						  afs_eproto_cb_fid_count);
299 
300 		call->buffer = kmalloc(array3_size(call->count, 3, 4),
301 				       GFP_KERNEL);
302 		if (!call->buffer)
303 			return -ENOMEM;
304 		afs_extract_to_buf(call, call->count * 3 * 4);
305 		call->unmarshall++;
306 
307 		/* Fall through */
308 	case 2:
309 		_debug("extract FID array");
310 		ret = afs_extract_data(call, true);
311 		if (ret < 0)
312 			return ret;
313 
314 		_debug("unmarshall FID array");
315 		call->request = kcalloc(call->count,
316 					sizeof(struct afs_callback_break),
317 					GFP_KERNEL);
318 		if (!call->request)
319 			return -ENOMEM;
320 
321 		cb = call->request;
322 		bp = call->buffer;
323 		for (loop = call->count; loop > 0; loop--, cb++) {
324 			cb->fid.vid	= ntohl(*bp++);
325 			cb->fid.vnode	= ntohl(*bp++);
326 			cb->fid.unique	= ntohl(*bp++);
327 		}
328 
329 		afs_extract_to_tmp(call);
330 		call->unmarshall++;
331 
332 		/* extract the callback array and its count in two steps */
333 		/* fall through */
334 	case 3:
335 		_debug("extract CB count");
336 		ret = afs_extract_data(call, true);
337 		if (ret < 0)
338 			return ret;
339 
340 		call->count2 = ntohl(call->tmp);
341 		_debug("CB count: %u", call->count2);
342 		if (call->count2 != call->count && call->count2 != 0)
343 			return afs_protocol_error(call, -EBADMSG,
344 						  afs_eproto_cb_count);
345 		call->_iter = &call->iter;
346 		iov_iter_discard(&call->iter, READ, call->count2 * 3 * 4);
347 		call->unmarshall++;
348 
349 		/* Fall through */
350 	case 4:
351 		_debug("extract discard %zu/%u",
352 		       iov_iter_count(&call->iter), call->count2 * 3 * 4);
353 
354 		ret = afs_extract_data(call, false);
355 		if (ret < 0)
356 			return ret;
357 
358 		call->unmarshall++;
359 	case 5:
360 		break;
361 	}
362 
363 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
364 		return afs_io_error(call, afs_io_error_cm_reply);
365 
366 	/* we'll need the file server record as that tells us which set of
367 	 * vnodes to operate upon */
368 	return afs_find_cm_server_by_peer(call);
369 }
370 
371 /*
372  * allow the fileserver to request callback state (re-)initialisation
373  */
374 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
375 {
376 	struct afs_call *call = container_of(work, struct afs_call, work);
377 
378 	_enter("{%p}", call->server);
379 
380 	if (call->server)
381 		afs_init_callback_state(call->server);
382 	afs_send_empty_reply(call);
383 	afs_put_call(call);
384 	_leave("");
385 }
386 
387 /*
388  * deliver request data to a CB.InitCallBackState call
389  */
390 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
391 {
392 	int ret;
393 
394 	_enter("");
395 
396 	afs_extract_discard(call, 0);
397 	ret = afs_extract_data(call, false);
398 	if (ret < 0)
399 		return ret;
400 
401 	/* we'll need the file server record as that tells us which set of
402 	 * vnodes to operate upon */
403 	return afs_find_cm_server_by_peer(call);
404 }
405 
406 /*
407  * deliver request data to a CB.InitCallBackState3 call
408  */
409 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
410 {
411 	struct afs_uuid *r;
412 	unsigned loop;
413 	__be32 *b;
414 	int ret;
415 
416 	_enter("");
417 
418 	_enter("{%u}", call->unmarshall);
419 
420 	switch (call->unmarshall) {
421 	case 0:
422 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
423 		if (!call->buffer)
424 			return -ENOMEM;
425 		afs_extract_to_buf(call, 11 * sizeof(__be32));
426 		call->unmarshall++;
427 
428 		/* Fall through */
429 	case 1:
430 		_debug("extract UUID");
431 		ret = afs_extract_data(call, false);
432 		switch (ret) {
433 		case 0:		break;
434 		case -EAGAIN:	return 0;
435 		default:	return ret;
436 		}
437 
438 		_debug("unmarshall UUID");
439 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
440 		if (!call->request)
441 			return -ENOMEM;
442 
443 		b = call->buffer;
444 		r = call->request;
445 		r->time_low			= b[0];
446 		r->time_mid			= htons(ntohl(b[1]));
447 		r->time_hi_and_version		= htons(ntohl(b[2]));
448 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
449 		r->clock_seq_low		= ntohl(b[4]);
450 
451 		for (loop = 0; loop < 6; loop++)
452 			r->node[loop] = ntohl(b[loop + 5]);
453 
454 		call->unmarshall++;
455 
456 	case 2:
457 		break;
458 	}
459 
460 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
461 		return afs_io_error(call, afs_io_error_cm_reply);
462 
463 	/* we'll need the file server record as that tells us which set of
464 	 * vnodes to operate upon */
465 	return afs_find_cm_server_by_uuid(call, call->request);
466 }
467 
468 /*
469  * allow the fileserver to see if the cache manager is still alive
470  */
471 static void SRXAFSCB_Probe(struct work_struct *work)
472 {
473 	struct afs_call *call = container_of(work, struct afs_call, work);
474 
475 	_enter("");
476 	afs_send_empty_reply(call);
477 	afs_put_call(call);
478 	_leave("");
479 }
480 
481 /*
482  * deliver request data to a CB.Probe call
483  */
484 static int afs_deliver_cb_probe(struct afs_call *call)
485 {
486 	int ret;
487 
488 	_enter("");
489 
490 	afs_extract_discard(call, 0);
491 	ret = afs_extract_data(call, false);
492 	if (ret < 0)
493 		return ret;
494 
495 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
496 		return afs_io_error(call, afs_io_error_cm_reply);
497 	return afs_find_cm_server_by_peer(call);
498 }
499 
500 /*
501  * allow the fileserver to quickly find out if the fileserver has been rebooted
502  */
503 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
504 {
505 	struct afs_call *call = container_of(work, struct afs_call, work);
506 	struct afs_uuid *r = call->request;
507 
508 	struct {
509 		__be32	match;
510 	} reply;
511 
512 	_enter("");
513 
514 	if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
515 		reply.match = htonl(0);
516 	else
517 		reply.match = htonl(1);
518 
519 	afs_send_simple_reply(call, &reply, sizeof(reply));
520 	afs_put_call(call);
521 	_leave("");
522 }
523 
524 /*
525  * deliver request data to a CB.ProbeUuid call
526  */
527 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
528 {
529 	struct afs_uuid *r;
530 	unsigned loop;
531 	__be32 *b;
532 	int ret;
533 
534 	_enter("{%u}", call->unmarshall);
535 
536 	switch (call->unmarshall) {
537 	case 0:
538 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
539 		if (!call->buffer)
540 			return -ENOMEM;
541 		afs_extract_to_buf(call, 11 * sizeof(__be32));
542 		call->unmarshall++;
543 
544 		/* Fall through */
545 	case 1:
546 		_debug("extract UUID");
547 		ret = afs_extract_data(call, false);
548 		switch (ret) {
549 		case 0:		break;
550 		case -EAGAIN:	return 0;
551 		default:	return ret;
552 		}
553 
554 		_debug("unmarshall UUID");
555 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
556 		if (!call->request)
557 			return -ENOMEM;
558 
559 		b = call->buffer;
560 		r = call->request;
561 		r->time_low			= b[0];
562 		r->time_mid			= htons(ntohl(b[1]));
563 		r->time_hi_and_version		= htons(ntohl(b[2]));
564 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
565 		r->clock_seq_low		= ntohl(b[4]);
566 
567 		for (loop = 0; loop < 6; loop++)
568 			r->node[loop] = ntohl(b[loop + 5]);
569 
570 		call->unmarshall++;
571 
572 	case 2:
573 		break;
574 	}
575 
576 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
577 		return afs_io_error(call, afs_io_error_cm_reply);
578 	return afs_find_cm_server_by_uuid(call, call->request);
579 }
580 
581 /*
582  * allow the fileserver to ask about the cache manager's capabilities
583  */
584 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
585 {
586 	struct afs_call *call = container_of(work, struct afs_call, work);
587 	int loop;
588 
589 	struct {
590 		struct /* InterfaceAddr */ {
591 			__be32 nifs;
592 			__be32 uuid[11];
593 			__be32 ifaddr[32];
594 			__be32 netmask[32];
595 			__be32 mtu[32];
596 		} ia;
597 		struct /* Capabilities */ {
598 			__be32 capcount;
599 			__be32 caps[1];
600 		} cap;
601 	} reply;
602 
603 	_enter("");
604 
605 	memset(&reply, 0, sizeof(reply));
606 
607 	reply.ia.uuid[0] = call->net->uuid.time_low;
608 	reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
609 	reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
610 	reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
611 	reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
612 	for (loop = 0; loop < 6; loop++)
613 		reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
614 
615 	reply.cap.capcount = htonl(1);
616 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
617 	afs_send_simple_reply(call, &reply, sizeof(reply));
618 	afs_put_call(call);
619 	_leave("");
620 }
621 
622 /*
623  * deliver request data to a CB.TellMeAboutYourself call
624  */
625 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
626 {
627 	int ret;
628 
629 	_enter("");
630 
631 	afs_extract_discard(call, 0);
632 	ret = afs_extract_data(call, false);
633 	if (ret < 0)
634 		return ret;
635 
636 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
637 		return afs_io_error(call, afs_io_error_cm_reply);
638 	return afs_find_cm_server_by_peer(call);
639 }
640 
641 /*
642  * deliver request data to a YFS CB.CallBack call
643  */
644 static int afs_deliver_yfs_cb_callback(struct afs_call *call)
645 {
646 	struct afs_callback_break *cb;
647 	struct yfs_xdr_YFSFid *bp;
648 	size_t size;
649 	int ret, loop;
650 
651 	_enter("{%u}", call->unmarshall);
652 
653 	switch (call->unmarshall) {
654 	case 0:
655 		afs_extract_to_tmp(call);
656 		call->unmarshall++;
657 
658 		/* extract the FID array and its count in two steps */
659 		/* Fall through */
660 	case 1:
661 		_debug("extract FID count");
662 		ret = afs_extract_data(call, true);
663 		if (ret < 0)
664 			return ret;
665 
666 		call->count = ntohl(call->tmp);
667 		_debug("FID count: %u", call->count);
668 		if (call->count > YFSCBMAX)
669 			return afs_protocol_error(call, -EBADMSG,
670 						  afs_eproto_cb_fid_count);
671 
672 		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
673 		call->buffer = kmalloc(size, GFP_KERNEL);
674 		if (!call->buffer)
675 			return -ENOMEM;
676 		afs_extract_to_buf(call, size);
677 		call->unmarshall++;
678 
679 		/* Fall through */
680 	case 2:
681 		_debug("extract FID array");
682 		ret = afs_extract_data(call, false);
683 		if (ret < 0)
684 			return ret;
685 
686 		_debug("unmarshall FID array");
687 		call->request = kcalloc(call->count,
688 					sizeof(struct afs_callback_break),
689 					GFP_KERNEL);
690 		if (!call->request)
691 			return -ENOMEM;
692 
693 		cb = call->request;
694 		bp = call->buffer;
695 		for (loop = call->count; loop > 0; loop--, cb++) {
696 			cb->fid.vid	= xdr_to_u64(bp->volume);
697 			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
698 			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
699 			cb->fid.unique	= ntohl(bp->vnode.unique);
700 			bp++;
701 		}
702 
703 		afs_extract_to_tmp(call);
704 		call->unmarshall++;
705 
706 	case 3:
707 		break;
708 	}
709 
710 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
711 		return afs_io_error(call, afs_io_error_cm_reply);
712 
713 	/* We'll need the file server record as that tells us which set of
714 	 * vnodes to operate upon.
715 	 */
716 	return afs_find_cm_server_by_peer(call);
717 }
718