xref: /linux/fs/afs/cmservice.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
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 	switch (call->operation_ID) {
122 	case CBCallBack:
123 		call->type = &afs_SRXCBCallBack;
124 		return true;
125 	case CBInitCallBackState:
126 		call->type = &afs_SRXCBInitCallBackState;
127 		return true;
128 	case CBInitCallBackState3:
129 		call->type = &afs_SRXCBInitCallBackState3;
130 		return true;
131 	case CBProbe:
132 		call->type = &afs_SRXCBProbe;
133 		return true;
134 	case CBProbeUuid:
135 		call->type = &afs_SRXCBProbeUuid;
136 		return true;
137 	case CBTellMeAboutYourself:
138 		call->type = &afs_SRXCBTellMeAboutYourself;
139 		return true;
140 	case YFSCBCallBack:
141 		if (call->service_id != YFS_CM_SERVICE)
142 			return false;
143 		call->type = &afs_SRXYFSCB_CallBack;
144 		return true;
145 	default:
146 		return false;
147 	}
148 }
149 
150 /*
151  * Find the server record by peer address and record a probe to the cache
152  * manager from a server.
153  */
154 static int afs_find_cm_server_by_peer(struct afs_call *call)
155 {
156 	struct sockaddr_rxrpc srx;
157 	struct afs_server *server;
158 
159 	rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
160 
161 	server = afs_find_server(call->net, &srx);
162 	if (!server) {
163 		trace_afs_cm_no_server(call, &srx);
164 		return 0;
165 	}
166 
167 	call->server = server;
168 	return 0;
169 }
170 
171 /*
172  * Find the server record by server UUID and record a probe to the cache
173  * manager from a server.
174  */
175 static int afs_find_cm_server_by_uuid(struct afs_call *call,
176 				      struct afs_uuid *uuid)
177 {
178 	struct afs_server *server;
179 
180 	rcu_read_lock();
181 	server = afs_find_server_by_uuid(call->net, call->request);
182 	rcu_read_unlock();
183 	if (!server) {
184 		trace_afs_cm_no_server_u(call, call->request);
185 		return 0;
186 	}
187 
188 	call->server = server;
189 	return 0;
190 }
191 
192 /*
193  * Clean up a cache manager call.
194  */
195 static void afs_cm_destructor(struct afs_call *call)
196 {
197 	kfree(call->buffer);
198 	call->buffer = NULL;
199 }
200 
201 /*
202  * Abort a service call from within an action function.
203  */
204 static void afs_abort_service_call(struct afs_call *call, u32 abort_code, int error,
205 				   const char *why)
206 {
207 	rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
208 				abort_code, error, why);
209 	afs_set_call_complete(call, error, 0);
210 }
211 
212 /*
213  * The server supplied a list of callbacks that it wanted to break.
214  */
215 static void SRXAFSCB_CallBack(struct work_struct *work)
216 {
217 	struct afs_call *call = container_of(work, struct afs_call, work);
218 
219 	_enter("");
220 
221 	/* We need to break the callbacks before sending the reply as the
222 	 * server holds up change visibility till it receives our reply so as
223 	 * to maintain cache coherency.
224 	 */
225 	if (call->server) {
226 		trace_afs_server(call->server,
227 				 atomic_read(&call->server->ref),
228 				 atomic_read(&call->server->active),
229 				 afs_server_trace_callback);
230 		afs_break_callbacks(call->server, call->count, call->request);
231 	}
232 
233 	afs_send_empty_reply(call);
234 	afs_put_call(call);
235 	_leave("");
236 }
237 
238 /*
239  * deliver request data to a CB.CallBack call
240  */
241 static int afs_deliver_cb_callback(struct afs_call *call)
242 {
243 	struct afs_callback_break *cb;
244 	__be32 *bp;
245 	int ret, loop;
246 
247 	_enter("{%u}", call->unmarshall);
248 
249 	switch (call->unmarshall) {
250 	case 0:
251 		afs_extract_to_tmp(call);
252 		call->unmarshall++;
253 
254 		/* extract the FID array and its count in two steps */
255 		fallthrough;
256 	case 1:
257 		_debug("extract FID count");
258 		ret = afs_extract_data(call, true);
259 		if (ret < 0)
260 			return ret;
261 
262 		call->count = ntohl(call->tmp);
263 		_debug("FID count: %u", call->count);
264 		if (call->count > AFSCBMAX)
265 			return afs_protocol_error(call, afs_eproto_cb_fid_count);
266 
267 		call->buffer = kmalloc(array3_size(call->count, 3, 4),
268 				       GFP_KERNEL);
269 		if (!call->buffer)
270 			return -ENOMEM;
271 		afs_extract_to_buf(call, call->count * 3 * 4);
272 		call->unmarshall++;
273 
274 		fallthrough;
275 	case 2:
276 		_debug("extract FID array");
277 		ret = afs_extract_data(call, true);
278 		if (ret < 0)
279 			return ret;
280 
281 		_debug("unmarshall FID array");
282 		call->request = kcalloc(call->count,
283 					sizeof(struct afs_callback_break),
284 					GFP_KERNEL);
285 		if (!call->request)
286 			return -ENOMEM;
287 
288 		cb = call->request;
289 		bp = call->buffer;
290 		for (loop = call->count; loop > 0; loop--, cb++) {
291 			cb->fid.vid	= ntohl(*bp++);
292 			cb->fid.vnode	= ntohl(*bp++);
293 			cb->fid.unique	= ntohl(*bp++);
294 		}
295 
296 		afs_extract_to_tmp(call);
297 		call->unmarshall++;
298 
299 		/* extract the callback array and its count in two steps */
300 		fallthrough;
301 	case 3:
302 		_debug("extract CB count");
303 		ret = afs_extract_data(call, true);
304 		if (ret < 0)
305 			return ret;
306 
307 		call->count2 = ntohl(call->tmp);
308 		_debug("CB count: %u", call->count2);
309 		if (call->count2 != call->count && call->count2 != 0)
310 			return afs_protocol_error(call, afs_eproto_cb_count);
311 		call->iter = &call->def_iter;
312 		iov_iter_discard(&call->def_iter, READ, call->count2 * 3 * 4);
313 		call->unmarshall++;
314 
315 		fallthrough;
316 	case 4:
317 		_debug("extract discard %zu/%u",
318 		       iov_iter_count(call->iter), call->count2 * 3 * 4);
319 
320 		ret = afs_extract_data(call, false);
321 		if (ret < 0)
322 			return ret;
323 
324 		call->unmarshall++;
325 	case 5:
326 		break;
327 	}
328 
329 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
330 		return afs_io_error(call, afs_io_error_cm_reply);
331 
332 	/* we'll need the file server record as that tells us which set of
333 	 * vnodes to operate upon */
334 	return afs_find_cm_server_by_peer(call);
335 }
336 
337 /*
338  * allow the fileserver to request callback state (re-)initialisation
339  */
340 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
341 {
342 	struct afs_call *call = container_of(work, struct afs_call, work);
343 
344 	_enter("{%p}", call->server);
345 
346 	if (call->server)
347 		afs_init_callback_state(call->server);
348 	afs_send_empty_reply(call);
349 	afs_put_call(call);
350 	_leave("");
351 }
352 
353 /*
354  * deliver request data to a CB.InitCallBackState call
355  */
356 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
357 {
358 	int ret;
359 
360 	_enter("");
361 
362 	afs_extract_discard(call, 0);
363 	ret = afs_extract_data(call, false);
364 	if (ret < 0)
365 		return ret;
366 
367 	/* we'll need the file server record as that tells us which set of
368 	 * vnodes to operate upon */
369 	return afs_find_cm_server_by_peer(call);
370 }
371 
372 /*
373  * deliver request data to a CB.InitCallBackState3 call
374  */
375 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
376 {
377 	struct afs_uuid *r;
378 	unsigned loop;
379 	__be32 *b;
380 	int ret;
381 
382 	_enter("");
383 
384 	_enter("{%u}", call->unmarshall);
385 
386 	switch (call->unmarshall) {
387 	case 0:
388 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
389 		if (!call->buffer)
390 			return -ENOMEM;
391 		afs_extract_to_buf(call, 11 * sizeof(__be32));
392 		call->unmarshall++;
393 
394 		fallthrough;
395 	case 1:
396 		_debug("extract UUID");
397 		ret = afs_extract_data(call, false);
398 		switch (ret) {
399 		case 0:		break;
400 		case -EAGAIN:	return 0;
401 		default:	return ret;
402 		}
403 
404 		_debug("unmarshall UUID");
405 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
406 		if (!call->request)
407 			return -ENOMEM;
408 
409 		b = call->buffer;
410 		r = call->request;
411 		r->time_low			= b[0];
412 		r->time_mid			= htons(ntohl(b[1]));
413 		r->time_hi_and_version		= htons(ntohl(b[2]));
414 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
415 		r->clock_seq_low		= ntohl(b[4]);
416 
417 		for (loop = 0; loop < 6; loop++)
418 			r->node[loop] = ntohl(b[loop + 5]);
419 
420 		call->unmarshall++;
421 
422 	case 2:
423 		break;
424 	}
425 
426 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
427 		return afs_io_error(call, afs_io_error_cm_reply);
428 
429 	/* we'll need the file server record as that tells us which set of
430 	 * vnodes to operate upon */
431 	return afs_find_cm_server_by_uuid(call, call->request);
432 }
433 
434 /*
435  * allow the fileserver to see if the cache manager is still alive
436  */
437 static void SRXAFSCB_Probe(struct work_struct *work)
438 {
439 	struct afs_call *call = container_of(work, struct afs_call, work);
440 
441 	_enter("");
442 	afs_send_empty_reply(call);
443 	afs_put_call(call);
444 	_leave("");
445 }
446 
447 /*
448  * deliver request data to a CB.Probe call
449  */
450 static int afs_deliver_cb_probe(struct afs_call *call)
451 {
452 	int ret;
453 
454 	_enter("");
455 
456 	afs_extract_discard(call, 0);
457 	ret = afs_extract_data(call, false);
458 	if (ret < 0)
459 		return ret;
460 
461 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
462 		return afs_io_error(call, afs_io_error_cm_reply);
463 	return afs_find_cm_server_by_peer(call);
464 }
465 
466 /*
467  * Allow the fileserver to quickly find out if the cache manager has been
468  * rebooted.
469  */
470 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
471 {
472 	struct afs_call *call = container_of(work, struct afs_call, work);
473 	struct afs_uuid *r = call->request;
474 
475 	_enter("");
476 
477 	if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
478 		afs_send_empty_reply(call);
479 	else
480 		afs_abort_service_call(call, 1, 1, "K-1");
481 
482 	afs_put_call(call);
483 	_leave("");
484 }
485 
486 /*
487  * deliver request data to a CB.ProbeUuid call
488  */
489 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
490 {
491 	struct afs_uuid *r;
492 	unsigned loop;
493 	__be32 *b;
494 	int ret;
495 
496 	_enter("{%u}", call->unmarshall);
497 
498 	switch (call->unmarshall) {
499 	case 0:
500 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
501 		if (!call->buffer)
502 			return -ENOMEM;
503 		afs_extract_to_buf(call, 11 * sizeof(__be32));
504 		call->unmarshall++;
505 
506 		fallthrough;
507 	case 1:
508 		_debug("extract UUID");
509 		ret = afs_extract_data(call, false);
510 		switch (ret) {
511 		case 0:		break;
512 		case -EAGAIN:	return 0;
513 		default:	return ret;
514 		}
515 
516 		_debug("unmarshall UUID");
517 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
518 		if (!call->request)
519 			return -ENOMEM;
520 
521 		b = call->buffer;
522 		r = call->request;
523 		r->time_low			= b[0];
524 		r->time_mid			= htons(ntohl(b[1]));
525 		r->time_hi_and_version		= htons(ntohl(b[2]));
526 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
527 		r->clock_seq_low		= ntohl(b[4]);
528 
529 		for (loop = 0; loop < 6; loop++)
530 			r->node[loop] = ntohl(b[loop + 5]);
531 
532 		call->unmarshall++;
533 
534 	case 2:
535 		break;
536 	}
537 
538 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
539 		return afs_io_error(call, afs_io_error_cm_reply);
540 	return afs_find_cm_server_by_peer(call);
541 }
542 
543 /*
544  * allow the fileserver to ask about the cache manager's capabilities
545  */
546 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
547 {
548 	struct afs_call *call = container_of(work, struct afs_call, work);
549 	int loop;
550 
551 	struct {
552 		struct /* InterfaceAddr */ {
553 			__be32 nifs;
554 			__be32 uuid[11];
555 			__be32 ifaddr[32];
556 			__be32 netmask[32];
557 			__be32 mtu[32];
558 		} ia;
559 		struct /* Capabilities */ {
560 			__be32 capcount;
561 			__be32 caps[1];
562 		} cap;
563 	} reply;
564 
565 	_enter("");
566 
567 	memset(&reply, 0, sizeof(reply));
568 
569 	reply.ia.uuid[0] = call->net->uuid.time_low;
570 	reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
571 	reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
572 	reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
573 	reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
574 	for (loop = 0; loop < 6; loop++)
575 		reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
576 
577 	reply.cap.capcount = htonl(1);
578 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
579 	afs_send_simple_reply(call, &reply, sizeof(reply));
580 	afs_put_call(call);
581 	_leave("");
582 }
583 
584 /*
585  * deliver request data to a CB.TellMeAboutYourself call
586  */
587 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
588 {
589 	int ret;
590 
591 	_enter("");
592 
593 	afs_extract_discard(call, 0);
594 	ret = afs_extract_data(call, false);
595 	if (ret < 0)
596 		return ret;
597 
598 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
599 		return afs_io_error(call, afs_io_error_cm_reply);
600 	return afs_find_cm_server_by_peer(call);
601 }
602 
603 /*
604  * deliver request data to a YFS CB.CallBack call
605  */
606 static int afs_deliver_yfs_cb_callback(struct afs_call *call)
607 {
608 	struct afs_callback_break *cb;
609 	struct yfs_xdr_YFSFid *bp;
610 	size_t size;
611 	int ret, loop;
612 
613 	_enter("{%u}", call->unmarshall);
614 
615 	switch (call->unmarshall) {
616 	case 0:
617 		afs_extract_to_tmp(call);
618 		call->unmarshall++;
619 
620 		/* extract the FID array and its count in two steps */
621 		fallthrough;
622 	case 1:
623 		_debug("extract FID count");
624 		ret = afs_extract_data(call, true);
625 		if (ret < 0)
626 			return ret;
627 
628 		call->count = ntohl(call->tmp);
629 		_debug("FID count: %u", call->count);
630 		if (call->count > YFSCBMAX)
631 			return afs_protocol_error(call, afs_eproto_cb_fid_count);
632 
633 		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
634 		call->buffer = kmalloc(size, GFP_KERNEL);
635 		if (!call->buffer)
636 			return -ENOMEM;
637 		afs_extract_to_buf(call, size);
638 		call->unmarshall++;
639 
640 		fallthrough;
641 	case 2:
642 		_debug("extract FID array");
643 		ret = afs_extract_data(call, false);
644 		if (ret < 0)
645 			return ret;
646 
647 		_debug("unmarshall FID array");
648 		call->request = kcalloc(call->count,
649 					sizeof(struct afs_callback_break),
650 					GFP_KERNEL);
651 		if (!call->request)
652 			return -ENOMEM;
653 
654 		cb = call->request;
655 		bp = call->buffer;
656 		for (loop = call->count; loop > 0; loop--, cb++) {
657 			cb->fid.vid	= xdr_to_u64(bp->volume);
658 			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
659 			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
660 			cb->fid.unique	= ntohl(bp->vnode.unique);
661 			bp++;
662 		}
663 
664 		afs_extract_to_tmp(call);
665 		call->unmarshall++;
666 
667 	case 3:
668 		break;
669 	}
670 
671 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
672 		return afs_io_error(call, afs_io_error_cm_reply);
673 
674 	/* We'll need the file server record as that tells us which set of
675 	 * vnodes to operate upon.
676 	 */
677 	return afs_find_cm_server_by_peer(call);
678 }
679