xref: /openbmc/linux/fs/afs/cmservice.c (revision be709d48)
1 /* AFS Cache Manager Service
2  *
3  * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/sched.h>
16 #include <linux/ip.h>
17 #include "internal.h"
18 #include "afs_cm.h"
19 #include "protocol_yfs.h"
20 
21 static int afs_deliver_cb_init_call_back_state(struct afs_call *);
22 static int afs_deliver_cb_init_call_back_state3(struct afs_call *);
23 static int afs_deliver_cb_probe(struct afs_call *);
24 static int afs_deliver_cb_callback(struct afs_call *);
25 static int afs_deliver_cb_probe_uuid(struct afs_call *);
26 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
27 static void afs_cm_destructor(struct afs_call *);
28 static void SRXAFSCB_CallBack(struct work_struct *);
29 static void SRXAFSCB_InitCallBackState(struct work_struct *);
30 static void SRXAFSCB_Probe(struct work_struct *);
31 static void SRXAFSCB_ProbeUuid(struct work_struct *);
32 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
33 
34 static int afs_deliver_yfs_cb_callback(struct afs_call *);
35 
36 #define CM_NAME(name) \
37 	const char afs_SRXCB##name##_name[] __tracepoint_string =	\
38 		"CB." #name
39 
40 /*
41  * CB.CallBack operation type
42  */
43 static CM_NAME(CallBack);
44 static const struct afs_call_type afs_SRXCBCallBack = {
45 	.name		= afs_SRXCBCallBack_name,
46 	.deliver	= afs_deliver_cb_callback,
47 	.destructor	= afs_cm_destructor,
48 	.work		= SRXAFSCB_CallBack,
49 };
50 
51 /*
52  * CB.InitCallBackState operation type
53  */
54 static CM_NAME(InitCallBackState);
55 static const struct afs_call_type afs_SRXCBInitCallBackState = {
56 	.name		= afs_SRXCBInitCallBackState_name,
57 	.deliver	= afs_deliver_cb_init_call_back_state,
58 	.destructor	= afs_cm_destructor,
59 	.work		= SRXAFSCB_InitCallBackState,
60 };
61 
62 /*
63  * CB.InitCallBackState3 operation type
64  */
65 static CM_NAME(InitCallBackState3);
66 static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
67 	.name		= afs_SRXCBInitCallBackState3_name,
68 	.deliver	= afs_deliver_cb_init_call_back_state3,
69 	.destructor	= afs_cm_destructor,
70 	.work		= SRXAFSCB_InitCallBackState,
71 };
72 
73 /*
74  * CB.Probe operation type
75  */
76 static CM_NAME(Probe);
77 static const struct afs_call_type afs_SRXCBProbe = {
78 	.name		= afs_SRXCBProbe_name,
79 	.deliver	= afs_deliver_cb_probe,
80 	.destructor	= afs_cm_destructor,
81 	.work		= SRXAFSCB_Probe,
82 };
83 
84 /*
85  * CB.ProbeUuid operation type
86  */
87 static CM_NAME(ProbeUuid);
88 static const struct afs_call_type afs_SRXCBProbeUuid = {
89 	.name		= afs_SRXCBProbeUuid_name,
90 	.deliver	= afs_deliver_cb_probe_uuid,
91 	.destructor	= afs_cm_destructor,
92 	.work		= SRXAFSCB_ProbeUuid,
93 };
94 
95 /*
96  * CB.TellMeAboutYourself operation type
97  */
98 static CM_NAME(TellMeAboutYourself);
99 static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
100 	.name		= afs_SRXCBTellMeAboutYourself_name,
101 	.deliver	= afs_deliver_cb_tell_me_about_yourself,
102 	.destructor	= afs_cm_destructor,
103 	.work		= SRXAFSCB_TellMeAboutYourself,
104 };
105 
106 /*
107  * YFS CB.CallBack operation type
108  */
109 static CM_NAME(YFS_CallBack);
110 static const struct afs_call_type afs_SRXYFSCB_CallBack = {
111 	.name		= afs_SRXCBYFS_CallBack_name,
112 	.deliver	= afs_deliver_yfs_cb_callback,
113 	.destructor	= afs_cm_destructor,
114 	.work		= SRXAFSCB_CallBack,
115 };
116 
117 /*
118  * route an incoming cache manager call
119  * - return T if supported, F if not
120  */
121 bool afs_cm_incoming_call(struct afs_call *call)
122 {
123 	_enter("{%u, CB.OP %u}", call->service_id, call->operation_ID);
124 
125 	call->epoch = rxrpc_kernel_get_epoch(call->net->socket, call->rxcall);
126 
127 	switch (call->operation_ID) {
128 	case CBCallBack:
129 		call->type = &afs_SRXCBCallBack;
130 		return true;
131 	case CBInitCallBackState:
132 		call->type = &afs_SRXCBInitCallBackState;
133 		return true;
134 	case CBInitCallBackState3:
135 		call->type = &afs_SRXCBInitCallBackState3;
136 		return true;
137 	case CBProbe:
138 		call->type = &afs_SRXCBProbe;
139 		return true;
140 	case CBProbeUuid:
141 		call->type = &afs_SRXCBProbeUuid;
142 		return true;
143 	case CBTellMeAboutYourself:
144 		call->type = &afs_SRXCBTellMeAboutYourself;
145 		return true;
146 	case YFSCBCallBack:
147 		if (call->service_id != YFS_CM_SERVICE)
148 			return false;
149 		call->type = &afs_SRXYFSCB_CallBack;
150 		return true;
151 	default:
152 		return false;
153 	}
154 }
155 
156 /*
157  * Record a probe to the cache manager from a server.
158  */
159 static int afs_record_cm_probe(struct afs_call *call, struct afs_server *server)
160 {
161 	_enter("");
162 
163 	if (test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags) &&
164 	    !test_bit(AFS_SERVER_FL_PROBING, &server->flags)) {
165 		if (server->cm_epoch == call->epoch)
166 			return 0;
167 
168 		if (!server->probe.said_rebooted) {
169 			pr_notice("kAFS: FS rebooted %pU\n", &server->uuid);
170 			server->probe.said_rebooted = true;
171 		}
172 	}
173 
174 	spin_lock(&server->probe_lock);
175 
176 	if (!test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags)) {
177 		server->cm_epoch = call->epoch;
178 		server->probe.cm_epoch = call->epoch;
179 		goto out;
180 	}
181 
182 	if (server->probe.cm_probed &&
183 	    call->epoch != server->probe.cm_epoch &&
184 	    !server->probe.said_inconsistent) {
185 		pr_notice("kAFS: FS endpoints inconsistent %pU\n",
186 			  &server->uuid);
187 		server->probe.said_inconsistent = true;
188 	}
189 
190 	if (!server->probe.cm_probed || call->epoch == server->cm_epoch)
191 		server->probe.cm_epoch = server->cm_epoch;
192 
193 out:
194 	server->probe.cm_probed = true;
195 	spin_unlock(&server->probe_lock);
196 	return 0;
197 }
198 
199 /*
200  * Find the server record by peer address and record a probe to the cache
201  * manager from a server.
202  */
203 static int afs_find_cm_server_by_peer(struct afs_call *call)
204 {
205 	struct sockaddr_rxrpc srx;
206 	struct afs_server *server;
207 
208 	rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
209 
210 	server = afs_find_server(call->net, &srx);
211 	if (!server) {
212 		trace_afs_cm_no_server(call, &srx);
213 		return 0;
214 	}
215 
216 	call->cm_server = server;
217 	return afs_record_cm_probe(call, server);
218 }
219 
220 /*
221  * Find the server record by server UUID and record a probe to the cache
222  * manager from a server.
223  */
224 static int afs_find_cm_server_by_uuid(struct afs_call *call,
225 				      struct afs_uuid *uuid)
226 {
227 	struct afs_server *server;
228 
229 	rcu_read_lock();
230 	server = afs_find_server_by_uuid(call->net, call->request);
231 	rcu_read_unlock();
232 	if (!server) {
233 		trace_afs_cm_no_server_u(call, call->request);
234 		return 0;
235 	}
236 
237 	call->cm_server = server;
238 	return afs_record_cm_probe(call, server);
239 }
240 
241 /*
242  * Clean up a cache manager call.
243  */
244 static void afs_cm_destructor(struct afs_call *call)
245 {
246 	kfree(call->buffer);
247 	call->buffer = NULL;
248 }
249 
250 /*
251  * The server supplied a list of callbacks that it wanted to break.
252  */
253 static void SRXAFSCB_CallBack(struct work_struct *work)
254 {
255 	struct afs_call *call = container_of(work, struct afs_call, work);
256 
257 	_enter("");
258 
259 	/* We need to break the callbacks before sending the reply as the
260 	 * server holds up change visibility till it receives our reply so as
261 	 * to maintain cache coherency.
262 	 */
263 	if (call->cm_server)
264 		afs_break_callbacks(call->cm_server, call->count, call->request);
265 
266 	afs_send_empty_reply(call);
267 	afs_put_call(call);
268 	_leave("");
269 }
270 
271 /*
272  * deliver request data to a CB.CallBack call
273  */
274 static int afs_deliver_cb_callback(struct afs_call *call)
275 {
276 	struct afs_callback_break *cb;
277 	__be32 *bp;
278 	int ret, loop;
279 
280 	_enter("{%u}", call->unmarshall);
281 
282 	switch (call->unmarshall) {
283 	case 0:
284 		afs_extract_to_tmp(call);
285 		call->unmarshall++;
286 
287 		/* extract the FID array and its count in two steps */
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 	case 2:
308 		_debug("extract FID array");
309 		ret = afs_extract_data(call, true);
310 		if (ret < 0)
311 			return ret;
312 
313 		_debug("unmarshall FID array");
314 		call->request = kcalloc(call->count,
315 					sizeof(struct afs_callback_break),
316 					GFP_KERNEL);
317 		if (!call->request)
318 			return -ENOMEM;
319 
320 		cb = call->request;
321 		bp = call->buffer;
322 		for (loop = call->count; loop > 0; loop--, cb++) {
323 			cb->fid.vid	= ntohl(*bp++);
324 			cb->fid.vnode	= ntohl(*bp++);
325 			cb->fid.unique	= ntohl(*bp++);
326 		}
327 
328 		afs_extract_to_tmp(call);
329 		call->unmarshall++;
330 
331 		/* extract the callback array and its count in two steps */
332 	case 3:
333 		_debug("extract CB count");
334 		ret = afs_extract_data(call, true);
335 		if (ret < 0)
336 			return ret;
337 
338 		call->count2 = ntohl(call->tmp);
339 		_debug("CB count: %u", call->count2);
340 		if (call->count2 != call->count && call->count2 != 0)
341 			return afs_protocol_error(call, -EBADMSG,
342 						  afs_eproto_cb_count);
343 		call->_iter = &call->iter;
344 		iov_iter_discard(&call->iter, READ, call->count2 * 3 * 4);
345 		call->unmarshall++;
346 
347 	case 4:
348 		_debug("extract discard %zu/%u",
349 		       iov_iter_count(&call->iter), call->count2 * 3 * 4);
350 
351 		ret = afs_extract_data(call, false);
352 		if (ret < 0)
353 			return ret;
354 
355 		call->unmarshall++;
356 	case 5:
357 		break;
358 	}
359 
360 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
361 		return afs_io_error(call, afs_io_error_cm_reply);
362 
363 	/* we'll need the file server record as that tells us which set of
364 	 * vnodes to operate upon */
365 	return afs_find_cm_server_by_peer(call);
366 }
367 
368 /*
369  * allow the fileserver to request callback state (re-)initialisation
370  */
371 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
372 {
373 	struct afs_call *call = container_of(work, struct afs_call, work);
374 
375 	_enter("{%p}", call->cm_server);
376 
377 	if (call->cm_server)
378 		afs_init_callback_state(call->cm_server);
379 	afs_send_empty_reply(call);
380 	afs_put_call(call);
381 	_leave("");
382 }
383 
384 /*
385  * deliver request data to a CB.InitCallBackState call
386  */
387 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
388 {
389 	int ret;
390 
391 	_enter("");
392 
393 	afs_extract_discard(call, 0);
394 	ret = afs_extract_data(call, false);
395 	if (ret < 0)
396 		return ret;
397 
398 	/* we'll need the file server record as that tells us which set of
399 	 * vnodes to operate upon */
400 	return afs_find_cm_server_by_peer(call);
401 }
402 
403 /*
404  * deliver request data to a CB.InitCallBackState3 call
405  */
406 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
407 {
408 	struct afs_uuid *r;
409 	unsigned loop;
410 	__be32 *b;
411 	int ret;
412 
413 	_enter("");
414 
415 	_enter("{%u}", call->unmarshall);
416 
417 	switch (call->unmarshall) {
418 	case 0:
419 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
420 		if (!call->buffer)
421 			return -ENOMEM;
422 		afs_extract_to_buf(call, 11 * sizeof(__be32));
423 		call->unmarshall++;
424 
425 	case 1:
426 		_debug("extract UUID");
427 		ret = afs_extract_data(call, false);
428 		switch (ret) {
429 		case 0:		break;
430 		case -EAGAIN:	return 0;
431 		default:	return ret;
432 		}
433 
434 		_debug("unmarshall UUID");
435 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
436 		if (!call->request)
437 			return -ENOMEM;
438 
439 		b = call->buffer;
440 		r = call->request;
441 		r->time_low			= b[0];
442 		r->time_mid			= htons(ntohl(b[1]));
443 		r->time_hi_and_version		= htons(ntohl(b[2]));
444 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
445 		r->clock_seq_low		= ntohl(b[4]);
446 
447 		for (loop = 0; loop < 6; loop++)
448 			r->node[loop] = ntohl(b[loop + 5]);
449 
450 		call->unmarshall++;
451 
452 	case 2:
453 		break;
454 	}
455 
456 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
457 		return afs_io_error(call, afs_io_error_cm_reply);
458 
459 	/* we'll need the file server record as that tells us which set of
460 	 * vnodes to operate upon */
461 	return afs_find_cm_server_by_uuid(call, call->request);
462 }
463 
464 /*
465  * allow the fileserver to see if the cache manager is still alive
466  */
467 static void SRXAFSCB_Probe(struct work_struct *work)
468 {
469 	struct afs_call *call = container_of(work, struct afs_call, work);
470 
471 	_enter("");
472 	afs_send_empty_reply(call);
473 	afs_put_call(call);
474 	_leave("");
475 }
476 
477 /*
478  * deliver request data to a CB.Probe call
479  */
480 static int afs_deliver_cb_probe(struct afs_call *call)
481 {
482 	int ret;
483 
484 	_enter("");
485 
486 	afs_extract_discard(call, 0);
487 	ret = afs_extract_data(call, false);
488 	if (ret < 0)
489 		return ret;
490 
491 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
492 		return afs_io_error(call, afs_io_error_cm_reply);
493 	return afs_find_cm_server_by_peer(call);
494 }
495 
496 /*
497  * allow the fileserver to quickly find out if the fileserver has been rebooted
498  */
499 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
500 {
501 	struct afs_call *call = container_of(work, struct afs_call, work);
502 	struct afs_uuid *r = call->request;
503 
504 	struct {
505 		__be32	match;
506 	} reply;
507 
508 	_enter("");
509 
510 	if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
511 		reply.match = htonl(0);
512 	else
513 		reply.match = htonl(1);
514 
515 	afs_send_simple_reply(call, &reply, sizeof(reply));
516 	afs_put_call(call);
517 	_leave("");
518 }
519 
520 /*
521  * deliver request data to a CB.ProbeUuid call
522  */
523 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
524 {
525 	struct afs_uuid *r;
526 	unsigned loop;
527 	__be32 *b;
528 	int ret;
529 
530 	_enter("{%u}", call->unmarshall);
531 
532 	switch (call->unmarshall) {
533 	case 0:
534 		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
535 		if (!call->buffer)
536 			return -ENOMEM;
537 		afs_extract_to_buf(call, 11 * sizeof(__be32));
538 		call->unmarshall++;
539 
540 	case 1:
541 		_debug("extract UUID");
542 		ret = afs_extract_data(call, false);
543 		switch (ret) {
544 		case 0:		break;
545 		case -EAGAIN:	return 0;
546 		default:	return ret;
547 		}
548 
549 		_debug("unmarshall UUID");
550 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
551 		if (!call->request)
552 			return -ENOMEM;
553 
554 		b = call->buffer;
555 		r = call->request;
556 		r->time_low			= b[0];
557 		r->time_mid			= htons(ntohl(b[1]));
558 		r->time_hi_and_version		= htons(ntohl(b[2]));
559 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
560 		r->clock_seq_low		= ntohl(b[4]);
561 
562 		for (loop = 0; loop < 6; loop++)
563 			r->node[loop] = ntohl(b[loop + 5]);
564 
565 		call->unmarshall++;
566 
567 	case 2:
568 		break;
569 	}
570 
571 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
572 		return afs_io_error(call, afs_io_error_cm_reply);
573 	return afs_find_cm_server_by_uuid(call, call->request);
574 }
575 
576 /*
577  * allow the fileserver to ask about the cache manager's capabilities
578  */
579 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
580 {
581 	struct afs_interface *ifs;
582 	struct afs_call *call = container_of(work, struct afs_call, work);
583 	int loop, nifs;
584 
585 	struct {
586 		struct /* InterfaceAddr */ {
587 			__be32 nifs;
588 			__be32 uuid[11];
589 			__be32 ifaddr[32];
590 			__be32 netmask[32];
591 			__be32 mtu[32];
592 		} ia;
593 		struct /* Capabilities */ {
594 			__be32 capcount;
595 			__be32 caps[1];
596 		} cap;
597 	} reply;
598 
599 	_enter("");
600 
601 	nifs = 0;
602 	ifs = kcalloc(32, sizeof(*ifs), GFP_KERNEL);
603 	if (ifs) {
604 		nifs = afs_get_ipv4_interfaces(call->net, ifs, 32, false);
605 		if (nifs < 0) {
606 			kfree(ifs);
607 			ifs = NULL;
608 			nifs = 0;
609 		}
610 	}
611 
612 	memset(&reply, 0, sizeof(reply));
613 	reply.ia.nifs = htonl(nifs);
614 
615 	reply.ia.uuid[0] = call->net->uuid.time_low;
616 	reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
617 	reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
618 	reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
619 	reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
620 	for (loop = 0; loop < 6; loop++)
621 		reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
622 
623 	if (ifs) {
624 		for (loop = 0; loop < nifs; loop++) {
625 			reply.ia.ifaddr[loop] = ifs[loop].address.s_addr;
626 			reply.ia.netmask[loop] = ifs[loop].netmask.s_addr;
627 			reply.ia.mtu[loop] = htonl(ifs[loop].mtu);
628 		}
629 		kfree(ifs);
630 	}
631 
632 	reply.cap.capcount = htonl(1);
633 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
634 	afs_send_simple_reply(call, &reply, sizeof(reply));
635 	afs_put_call(call);
636 	_leave("");
637 }
638 
639 /*
640  * deliver request data to a CB.TellMeAboutYourself call
641  */
642 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
643 {
644 	int ret;
645 
646 	_enter("");
647 
648 	afs_extract_discard(call, 0);
649 	ret = afs_extract_data(call, false);
650 	if (ret < 0)
651 		return ret;
652 
653 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
654 		return afs_io_error(call, afs_io_error_cm_reply);
655 	return afs_find_cm_server_by_peer(call);
656 }
657 
658 /*
659  * deliver request data to a YFS CB.CallBack call
660  */
661 static int afs_deliver_yfs_cb_callback(struct afs_call *call)
662 {
663 	struct afs_callback_break *cb;
664 	struct yfs_xdr_YFSFid *bp;
665 	size_t size;
666 	int ret, loop;
667 
668 	_enter("{%u}", call->unmarshall);
669 
670 	switch (call->unmarshall) {
671 	case 0:
672 		afs_extract_to_tmp(call);
673 		call->unmarshall++;
674 
675 		/* extract the FID array and its count in two steps */
676 	case 1:
677 		_debug("extract FID count");
678 		ret = afs_extract_data(call, true);
679 		if (ret < 0)
680 			return ret;
681 
682 		call->count = ntohl(call->tmp);
683 		_debug("FID count: %u", call->count);
684 		if (call->count > YFSCBMAX)
685 			return afs_protocol_error(call, -EBADMSG,
686 						  afs_eproto_cb_fid_count);
687 
688 		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
689 		call->buffer = kmalloc(size, GFP_KERNEL);
690 		if (!call->buffer)
691 			return -ENOMEM;
692 		afs_extract_to_buf(call, size);
693 		call->unmarshall++;
694 
695 	case 2:
696 		_debug("extract FID array");
697 		ret = afs_extract_data(call, false);
698 		if (ret < 0)
699 			return ret;
700 
701 		_debug("unmarshall FID array");
702 		call->request = kcalloc(call->count,
703 					sizeof(struct afs_callback_break),
704 					GFP_KERNEL);
705 		if (!call->request)
706 			return -ENOMEM;
707 
708 		cb = call->request;
709 		bp = call->buffer;
710 		for (loop = call->count; loop > 0; loop--, cb++) {
711 			cb->fid.vid	= xdr_to_u64(bp->volume);
712 			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
713 			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
714 			cb->fid.unique	= ntohl(bp->vnode.unique);
715 			bp++;
716 		}
717 
718 		afs_extract_to_tmp(call);
719 		call->unmarshall++;
720 
721 	case 3:
722 		break;
723 	}
724 
725 	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
726 		return afs_io_error(call, afs_io_error_cm_reply);
727 
728 	/* We'll need the file server record as that tells us which set of
729 	 * vnodes to operate upon.
730 	 */
731 	return afs_find_cm_server_by_peer(call);
732 }
733