xref: /linux/fs/afs/cmservice.c (revision 2d7f3d1a5866705be2393150e1ffdf67030ab88d)
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  * Find the server record by peer address and record a probe to the cache
143  * manager from a server.
144  */
145 static int afs_find_cm_server_by_peer(struct afs_call *call)
146 {
147 	struct sockaddr_rxrpc srx;
148 	struct afs_server *server;
149 	struct rxrpc_peer *peer;
150 
151 	peer = rxrpc_kernel_get_call_peer(call->net->socket, call->rxcall);
152 
153 	server = afs_find_server(call->net, peer);
154 	if (!server) {
155 		trace_afs_cm_no_server(call, &srx);
156 		return 0;
157 	}
158 
159 	call->server = server;
160 	return 0;
161 }
162 
163 /*
164  * Find the server record by server UUID and record a probe to the cache
165  * manager from a server.
166  */
167 static int afs_find_cm_server_by_uuid(struct afs_call *call,
168 				      struct afs_uuid *uuid)
169 {
170 	struct afs_server *server;
171 
172 	rcu_read_lock();
173 	server = afs_find_server_by_uuid(call->net, call->request);
174 	rcu_read_unlock();
175 	if (!server) {
176 		trace_afs_cm_no_server_u(call, call->request);
177 		return 0;
178 	}
179 
180 	call->server = server;
181 	return 0;
182 }
183 
184 /*
185  * Clean up a cache manager call.
186  */
187 static void afs_cm_destructor(struct afs_call *call)
188 {
189 	kfree(call->buffer);
190 	call->buffer = NULL;
191 }
192 
193 /*
194  * Abort a service call from within an action function.
195  */
196 static void afs_abort_service_call(struct afs_call *call, u32 abort_code, int error,
197 				   enum rxrpc_abort_reason why)
198 {
199 	rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
200 				abort_code, error, why);
201 	afs_set_call_complete(call, error, 0);
202 }
203 
204 /*
205  * The server supplied a list of callbacks that it wanted to break.
206  */
207 static void SRXAFSCB_CallBack(struct work_struct *work)
208 {
209 	struct afs_call *call = container_of(work, struct afs_call, work);
210 
211 	_enter("");
212 
213 	/* We need to break the callbacks before sending the reply as the
214 	 * server holds up change visibility till it receives our reply so as
215 	 * to maintain cache coherency.
216 	 */
217 	if (call->server) {
218 		trace_afs_server(call->server->debug_id,
219 				 refcount_read(&call->server->ref),
220 				 atomic_read(&call->server->active),
221 				 afs_server_trace_callback);
222 		afs_break_callbacks(call->server, call->count, call->request);
223 	}
224 
225 	afs_send_empty_reply(call);
226 	afs_put_call(call);
227 	_leave("");
228 }
229 
230 /*
231  * deliver request data to a CB.CallBack call
232  */
233 static int afs_deliver_cb_callback(struct afs_call *call)
234 {
235 	struct afs_callback_break *cb;
236 	__be32 *bp;
237 	int ret, loop;
238 
239 	_enter("{%u}", call->unmarshall);
240 
241 	switch (call->unmarshall) {
242 	case 0:
243 		afs_extract_to_tmp(call);
244 		call->unmarshall++;
245 
246 		/* extract the FID array and its count in two steps */
247 		fallthrough;
248 	case 1:
249 		_debug("extract FID count");
250 		ret = afs_extract_data(call, true);
251 		if (ret < 0)
252 			return ret;
253 
254 		call->count = ntohl(call->tmp);
255 		_debug("FID count: %u", call->count);
256 		if (call->count > AFSCBMAX)
257 			return afs_protocol_error(call, afs_eproto_cb_fid_count);
258 
259 		call->buffer = kmalloc(array3_size(call->count, 3, 4),
260 				       GFP_KERNEL);
261 		if (!call->buffer)
262 			return -ENOMEM;
263 		afs_extract_to_buf(call, call->count * 3 * 4);
264 		call->unmarshall++;
265 
266 		fallthrough;
267 	case 2:
268 		_debug("extract FID array");
269 		ret = afs_extract_data(call, true);
270 		if (ret < 0)
271 			return ret;
272 
273 		_debug("unmarshall FID array");
274 		call->request = kcalloc(call->count,
275 					sizeof(struct afs_callback_break),
276 					GFP_KERNEL);
277 		if (!call->request)
278 			return -ENOMEM;
279 
280 		cb = call->request;
281 		bp = call->buffer;
282 		for (loop = call->count; loop > 0; loop--, cb++) {
283 			cb->fid.vid	= ntohl(*bp++);
284 			cb->fid.vnode	= ntohl(*bp++);
285 			cb->fid.unique	= ntohl(*bp++);
286 		}
287 
288 		afs_extract_to_tmp(call);
289 		call->unmarshall++;
290 
291 		/* extract the callback array and its count in two steps */
292 		fallthrough;
293 	case 3:
294 		_debug("extract CB count");
295 		ret = afs_extract_data(call, true);
296 		if (ret < 0)
297 			return ret;
298 
299 		call->count2 = ntohl(call->tmp);
300 		_debug("CB count: %u", call->count2);
301 		if (call->count2 != call->count && call->count2 != 0)
302 			return afs_protocol_error(call, afs_eproto_cb_count);
303 		call->iter = &call->def_iter;
304 		iov_iter_discard(&call->def_iter, ITER_DEST, call->count2 * 3 * 4);
305 		call->unmarshall++;
306 
307 		fallthrough;
308 	case 4:
309 		_debug("extract discard %zu/%u",
310 		       iov_iter_count(call->iter), call->count2 * 3 * 4);
311 
312 		ret = afs_extract_data(call, false);
313 		if (ret < 0)
314 			return ret;
315 
316 		call->unmarshall++;
317 		fallthrough;
318 
319 	case 5:
320 		break;
321 	}
322 
323 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
324 		return afs_io_error(call, afs_io_error_cm_reply);
325 
326 	/* we'll need the file server record as that tells us which set of
327 	 * vnodes to operate upon */
328 	return afs_find_cm_server_by_peer(call);
329 }
330 
331 /*
332  * allow the fileserver to request callback state (re-)initialisation
333  */
334 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
335 {
336 	struct afs_call *call = container_of(work, struct afs_call, work);
337 
338 	_enter("{%p}", call->server);
339 
340 	if (call->server)
341 		afs_init_callback_state(call->server);
342 	afs_send_empty_reply(call);
343 	afs_put_call(call);
344 	_leave("");
345 }
346 
347 /*
348  * deliver request data to a CB.InitCallBackState call
349  */
350 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
351 {
352 	int ret;
353 
354 	_enter("");
355 
356 	afs_extract_discard(call, 0);
357 	ret = afs_extract_data(call, false);
358 	if (ret < 0)
359 		return ret;
360 
361 	/* we'll need the file server record as that tells us which set of
362 	 * vnodes to operate upon */
363 	return afs_find_cm_server_by_peer(call);
364 }
365 
366 /*
367  * deliver request data to a CB.InitCallBackState3 call
368  */
369 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
370 {
371 	struct afs_uuid *r;
372 	unsigned loop;
373 	__be32 *b;
374 	int ret;
375 
376 	_enter("");
377 
378 	_enter("{%u}", call->unmarshall);
379 
380 	switch (call->unmarshall) {
381 	case 0:
382 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
383 		if (!call->buffer)
384 			return -ENOMEM;
385 		afs_extract_to_buf(call, 11 * sizeof(__be32));
386 		call->unmarshall++;
387 
388 		fallthrough;
389 	case 1:
390 		_debug("extract UUID");
391 		ret = afs_extract_data(call, false);
392 		switch (ret) {
393 		case 0:		break;
394 		case -EAGAIN:	return 0;
395 		default:	return ret;
396 		}
397 
398 		_debug("unmarshall UUID");
399 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
400 		if (!call->request)
401 			return -ENOMEM;
402 
403 		b = call->buffer;
404 		r = call->request;
405 		r->time_low			= b[0];
406 		r->time_mid			= htons(ntohl(b[1]));
407 		r->time_hi_and_version		= htons(ntohl(b[2]));
408 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
409 		r->clock_seq_low		= ntohl(b[4]);
410 
411 		for (loop = 0; loop < 6; loop++)
412 			r->node[loop] = ntohl(b[loop + 5]);
413 
414 		call->unmarshall++;
415 		fallthrough;
416 
417 	case 2:
418 		break;
419 	}
420 
421 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
422 		return afs_io_error(call, afs_io_error_cm_reply);
423 
424 	/* we'll need the file server record as that tells us which set of
425 	 * vnodes to operate upon */
426 	return afs_find_cm_server_by_uuid(call, call->request);
427 }
428 
429 /*
430  * allow the fileserver to see if the cache manager is still alive
431  */
432 static void SRXAFSCB_Probe(struct work_struct *work)
433 {
434 	struct afs_call *call = container_of(work, struct afs_call, work);
435 
436 	_enter("");
437 	afs_send_empty_reply(call);
438 	afs_put_call(call);
439 	_leave("");
440 }
441 
442 /*
443  * deliver request data to a CB.Probe call
444  */
445 static int afs_deliver_cb_probe(struct afs_call *call)
446 {
447 	int ret;
448 
449 	_enter("");
450 
451 	afs_extract_discard(call, 0);
452 	ret = afs_extract_data(call, false);
453 	if (ret < 0)
454 		return ret;
455 
456 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
457 		return afs_io_error(call, afs_io_error_cm_reply);
458 	return afs_find_cm_server_by_peer(call);
459 }
460 
461 /*
462  * Allow the fileserver to quickly find out if the cache manager has been
463  * rebooted.
464  */
465 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
466 {
467 	struct afs_call *call = container_of(work, struct afs_call, work);
468 	struct afs_uuid *r = call->request;
469 
470 	_enter("");
471 
472 	if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
473 		afs_send_empty_reply(call);
474 	else
475 		afs_abort_service_call(call, 1, 1, afs_abort_probeuuid_negative);
476 
477 	afs_put_call(call);
478 	_leave("");
479 }
480 
481 /*
482  * deliver request data to a CB.ProbeUuid call
483  */
484 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
485 {
486 	struct afs_uuid *r;
487 	unsigned loop;
488 	__be32 *b;
489 	int ret;
490 
491 	_enter("{%u}", call->unmarshall);
492 
493 	switch (call->unmarshall) {
494 	case 0:
495 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
496 		if (!call->buffer)
497 			return -ENOMEM;
498 		afs_extract_to_buf(call, 11 * sizeof(__be32));
499 		call->unmarshall++;
500 
501 		fallthrough;
502 	case 1:
503 		_debug("extract UUID");
504 		ret = afs_extract_data(call, false);
505 		switch (ret) {
506 		case 0:		break;
507 		case -EAGAIN:	return 0;
508 		default:	return ret;
509 		}
510 
511 		_debug("unmarshall UUID");
512 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
513 		if (!call->request)
514 			return -ENOMEM;
515 
516 		b = call->buffer;
517 		r = call->request;
518 		r->time_low			= b[0];
519 		r->time_mid			= htons(ntohl(b[1]));
520 		r->time_hi_and_version		= htons(ntohl(b[2]));
521 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
522 		r->clock_seq_low		= ntohl(b[4]);
523 
524 		for (loop = 0; loop < 6; loop++)
525 			r->node[loop] = ntohl(b[loop + 5]);
526 
527 		call->unmarshall++;
528 		fallthrough;
529 
530 	case 2:
531 		break;
532 	}
533 
534 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
535 		return afs_io_error(call, afs_io_error_cm_reply);
536 	return afs_find_cm_server_by_peer(call);
537 }
538 
539 /*
540  * allow the fileserver to ask about the cache manager's capabilities
541  */
542 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
543 {
544 	struct afs_call *call = container_of(work, struct afs_call, work);
545 	int loop;
546 
547 	struct {
548 		struct /* InterfaceAddr */ {
549 			__be32 nifs;
550 			__be32 uuid[11];
551 			__be32 ifaddr[32];
552 			__be32 netmask[32];
553 			__be32 mtu[32];
554 		} ia;
555 		struct /* Capabilities */ {
556 			__be32 capcount;
557 			__be32 caps[1];
558 		} cap;
559 	} reply;
560 
561 	_enter("");
562 
563 	memset(&reply, 0, sizeof(reply));
564 
565 	reply.ia.uuid[0] = call->net->uuid.time_low;
566 	reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
567 	reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
568 	reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
569 	reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
570 	for (loop = 0; loop < 6; loop++)
571 		reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
572 
573 	reply.cap.capcount = htonl(1);
574 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
575 	afs_send_simple_reply(call, &reply, sizeof(reply));
576 	afs_put_call(call);
577 	_leave("");
578 }
579 
580 /*
581  * deliver request data to a CB.TellMeAboutYourself call
582  */
583 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
584 {
585 	int ret;
586 
587 	_enter("");
588 
589 	afs_extract_discard(call, 0);
590 	ret = afs_extract_data(call, false);
591 	if (ret < 0)
592 		return ret;
593 
594 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
595 		return afs_io_error(call, afs_io_error_cm_reply);
596 	return afs_find_cm_server_by_peer(call);
597 }
598 
599 /*
600  * deliver request data to a YFS CB.CallBack call
601  */
602 static int afs_deliver_yfs_cb_callback(struct afs_call *call)
603 {
604 	struct afs_callback_break *cb;
605 	struct yfs_xdr_YFSFid *bp;
606 	size_t size;
607 	int ret, loop;
608 
609 	_enter("{%u}", call->unmarshall);
610 
611 	switch (call->unmarshall) {
612 	case 0:
613 		afs_extract_to_tmp(call);
614 		call->unmarshall++;
615 
616 		/* extract the FID array and its count in two steps */
617 		fallthrough;
618 	case 1:
619 		_debug("extract FID count");
620 		ret = afs_extract_data(call, true);
621 		if (ret < 0)
622 			return ret;
623 
624 		call->count = ntohl(call->tmp);
625 		_debug("FID count: %u", call->count);
626 		if (call->count > YFSCBMAX)
627 			return afs_protocol_error(call, afs_eproto_cb_fid_count);
628 
629 		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
630 		call->buffer = kmalloc(size, GFP_KERNEL);
631 		if (!call->buffer)
632 			return -ENOMEM;
633 		afs_extract_to_buf(call, size);
634 		call->unmarshall++;
635 
636 		fallthrough;
637 	case 2:
638 		_debug("extract FID array");
639 		ret = afs_extract_data(call, false);
640 		if (ret < 0)
641 			return ret;
642 
643 		_debug("unmarshall FID array");
644 		call->request = kcalloc(call->count,
645 					sizeof(struct afs_callback_break),
646 					GFP_KERNEL);
647 		if (!call->request)
648 			return -ENOMEM;
649 
650 		cb = call->request;
651 		bp = call->buffer;
652 		for (loop = call->count; loop > 0; loop--, cb++) {
653 			cb->fid.vid	= xdr_to_u64(bp->volume);
654 			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
655 			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
656 			cb->fid.unique	= ntohl(bp->vnode.unique);
657 			bp++;
658 		}
659 
660 		afs_extract_to_tmp(call);
661 		call->unmarshall++;
662 		fallthrough;
663 
664 	case 3:
665 		break;
666 	}
667 
668 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
669 		return afs_io_error(call, afs_io_error_cm_reply);
670 
671 	/* We'll need the file server record as that tells us which set of
672 	 * vnodes to operate upon.
673 	 */
674 	return afs_find_cm_server_by_peer(call);
675 }
676