xref: /openbmc/linux/fs/afs/cmservice.c (revision 9dbbc3b9)
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 		fallthrough;
326 
327 	case 5:
328 		break;
329 	}
330 
331 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
332 		return afs_io_error(call, afs_io_error_cm_reply);
333 
334 	/* we'll need the file server record as that tells us which set of
335 	 * vnodes to operate upon */
336 	return afs_find_cm_server_by_peer(call);
337 }
338 
339 /*
340  * allow the fileserver to request callback state (re-)initialisation
341  */
342 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
343 {
344 	struct afs_call *call = container_of(work, struct afs_call, work);
345 
346 	_enter("{%p}", call->server);
347 
348 	if (call->server)
349 		afs_init_callback_state(call->server);
350 	afs_send_empty_reply(call);
351 	afs_put_call(call);
352 	_leave("");
353 }
354 
355 /*
356  * deliver request data to a CB.InitCallBackState call
357  */
358 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
359 {
360 	int ret;
361 
362 	_enter("");
363 
364 	afs_extract_discard(call, 0);
365 	ret = afs_extract_data(call, false);
366 	if (ret < 0)
367 		return ret;
368 
369 	/* we'll need the file server record as that tells us which set of
370 	 * vnodes to operate upon */
371 	return afs_find_cm_server_by_peer(call);
372 }
373 
374 /*
375  * deliver request data to a CB.InitCallBackState3 call
376  */
377 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
378 {
379 	struct afs_uuid *r;
380 	unsigned loop;
381 	__be32 *b;
382 	int ret;
383 
384 	_enter("");
385 
386 	_enter("{%u}", call->unmarshall);
387 
388 	switch (call->unmarshall) {
389 	case 0:
390 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
391 		if (!call->buffer)
392 			return -ENOMEM;
393 		afs_extract_to_buf(call, 11 * sizeof(__be32));
394 		call->unmarshall++;
395 
396 		fallthrough;
397 	case 1:
398 		_debug("extract UUID");
399 		ret = afs_extract_data(call, false);
400 		switch (ret) {
401 		case 0:		break;
402 		case -EAGAIN:	return 0;
403 		default:	return ret;
404 		}
405 
406 		_debug("unmarshall UUID");
407 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
408 		if (!call->request)
409 			return -ENOMEM;
410 
411 		b = call->buffer;
412 		r = call->request;
413 		r->time_low			= b[0];
414 		r->time_mid			= htons(ntohl(b[1]));
415 		r->time_hi_and_version		= htons(ntohl(b[2]));
416 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
417 		r->clock_seq_low		= ntohl(b[4]);
418 
419 		for (loop = 0; loop < 6; loop++)
420 			r->node[loop] = ntohl(b[loop + 5]);
421 
422 		call->unmarshall++;
423 		fallthrough;
424 
425 	case 2:
426 		break;
427 	}
428 
429 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
430 		return afs_io_error(call, afs_io_error_cm_reply);
431 
432 	/* we'll need the file server record as that tells us which set of
433 	 * vnodes to operate upon */
434 	return afs_find_cm_server_by_uuid(call, call->request);
435 }
436 
437 /*
438  * allow the fileserver to see if the cache manager is still alive
439  */
440 static void SRXAFSCB_Probe(struct work_struct *work)
441 {
442 	struct afs_call *call = container_of(work, struct afs_call, work);
443 
444 	_enter("");
445 	afs_send_empty_reply(call);
446 	afs_put_call(call);
447 	_leave("");
448 }
449 
450 /*
451  * deliver request data to a CB.Probe call
452  */
453 static int afs_deliver_cb_probe(struct afs_call *call)
454 {
455 	int ret;
456 
457 	_enter("");
458 
459 	afs_extract_discard(call, 0);
460 	ret = afs_extract_data(call, false);
461 	if (ret < 0)
462 		return ret;
463 
464 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
465 		return afs_io_error(call, afs_io_error_cm_reply);
466 	return afs_find_cm_server_by_peer(call);
467 }
468 
469 /*
470  * Allow the fileserver to quickly find out if the cache manager has been
471  * rebooted.
472  */
473 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
474 {
475 	struct afs_call *call = container_of(work, struct afs_call, work);
476 	struct afs_uuid *r = call->request;
477 
478 	_enter("");
479 
480 	if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
481 		afs_send_empty_reply(call);
482 	else
483 		afs_abort_service_call(call, 1, 1, "K-1");
484 
485 	afs_put_call(call);
486 	_leave("");
487 }
488 
489 /*
490  * deliver request data to a CB.ProbeUuid call
491  */
492 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
493 {
494 	struct afs_uuid *r;
495 	unsigned loop;
496 	__be32 *b;
497 	int ret;
498 
499 	_enter("{%u}", call->unmarshall);
500 
501 	switch (call->unmarshall) {
502 	case 0:
503 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
504 		if (!call->buffer)
505 			return -ENOMEM;
506 		afs_extract_to_buf(call, 11 * sizeof(__be32));
507 		call->unmarshall++;
508 
509 		fallthrough;
510 	case 1:
511 		_debug("extract UUID");
512 		ret = afs_extract_data(call, false);
513 		switch (ret) {
514 		case 0:		break;
515 		case -EAGAIN:	return 0;
516 		default:	return ret;
517 		}
518 
519 		_debug("unmarshall UUID");
520 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
521 		if (!call->request)
522 			return -ENOMEM;
523 
524 		b = call->buffer;
525 		r = call->request;
526 		r->time_low			= b[0];
527 		r->time_mid			= htons(ntohl(b[1]));
528 		r->time_hi_and_version		= htons(ntohl(b[2]));
529 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
530 		r->clock_seq_low		= ntohl(b[4]);
531 
532 		for (loop = 0; loop < 6; loop++)
533 			r->node[loop] = ntohl(b[loop + 5]);
534 
535 		call->unmarshall++;
536 		fallthrough;
537 
538 	case 2:
539 		break;
540 	}
541 
542 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
543 		return afs_io_error(call, afs_io_error_cm_reply);
544 	return afs_find_cm_server_by_peer(call);
545 }
546 
547 /*
548  * allow the fileserver to ask about the cache manager's capabilities
549  */
550 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
551 {
552 	struct afs_call *call = container_of(work, struct afs_call, work);
553 	int loop;
554 
555 	struct {
556 		struct /* InterfaceAddr */ {
557 			__be32 nifs;
558 			__be32 uuid[11];
559 			__be32 ifaddr[32];
560 			__be32 netmask[32];
561 			__be32 mtu[32];
562 		} ia;
563 		struct /* Capabilities */ {
564 			__be32 capcount;
565 			__be32 caps[1];
566 		} cap;
567 	} reply;
568 
569 	_enter("");
570 
571 	memset(&reply, 0, sizeof(reply));
572 
573 	reply.ia.uuid[0] = call->net->uuid.time_low;
574 	reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
575 	reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
576 	reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
577 	reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
578 	for (loop = 0; loop < 6; loop++)
579 		reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
580 
581 	reply.cap.capcount = htonl(1);
582 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
583 	afs_send_simple_reply(call, &reply, sizeof(reply));
584 	afs_put_call(call);
585 	_leave("");
586 }
587 
588 /*
589  * deliver request data to a CB.TellMeAboutYourself call
590  */
591 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
592 {
593 	int ret;
594 
595 	_enter("");
596 
597 	afs_extract_discard(call, 0);
598 	ret = afs_extract_data(call, false);
599 	if (ret < 0)
600 		return ret;
601 
602 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
603 		return afs_io_error(call, afs_io_error_cm_reply);
604 	return afs_find_cm_server_by_peer(call);
605 }
606 
607 /*
608  * deliver request data to a YFS CB.CallBack call
609  */
610 static int afs_deliver_yfs_cb_callback(struct afs_call *call)
611 {
612 	struct afs_callback_break *cb;
613 	struct yfs_xdr_YFSFid *bp;
614 	size_t size;
615 	int ret, loop;
616 
617 	_enter("{%u}", call->unmarshall);
618 
619 	switch (call->unmarshall) {
620 	case 0:
621 		afs_extract_to_tmp(call);
622 		call->unmarshall++;
623 
624 		/* extract the FID array and its count in two steps */
625 		fallthrough;
626 	case 1:
627 		_debug("extract FID count");
628 		ret = afs_extract_data(call, true);
629 		if (ret < 0)
630 			return ret;
631 
632 		call->count = ntohl(call->tmp);
633 		_debug("FID count: %u", call->count);
634 		if (call->count > YFSCBMAX)
635 			return afs_protocol_error(call, afs_eproto_cb_fid_count);
636 
637 		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
638 		call->buffer = kmalloc(size, GFP_KERNEL);
639 		if (!call->buffer)
640 			return -ENOMEM;
641 		afs_extract_to_buf(call, size);
642 		call->unmarshall++;
643 
644 		fallthrough;
645 	case 2:
646 		_debug("extract FID array");
647 		ret = afs_extract_data(call, false);
648 		if (ret < 0)
649 			return ret;
650 
651 		_debug("unmarshall FID array");
652 		call->request = kcalloc(call->count,
653 					sizeof(struct afs_callback_break),
654 					GFP_KERNEL);
655 		if (!call->request)
656 			return -ENOMEM;
657 
658 		cb = call->request;
659 		bp = call->buffer;
660 		for (loop = call->count; loop > 0; loop--, cb++) {
661 			cb->fid.vid	= xdr_to_u64(bp->volume);
662 			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
663 			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
664 			cb->fid.unique	= ntohl(bp->vnode.unique);
665 			bp++;
666 		}
667 
668 		afs_extract_to_tmp(call);
669 		call->unmarshall++;
670 		fallthrough;
671 
672 	case 3:
673 		break;
674 	}
675 
676 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
677 		return afs_io_error(call, afs_io_error_cm_reply);
678 
679 	/* We'll need the file server record as that tells us which set of
680 	 * vnodes to operate upon.
681 	 */
682 	return afs_find_cm_server_by_peer(call);
683 }
684