1// SPDX-License-Identifier: GPL-2.0-or-later
2/* AFS Volume Location Service client
3 *
4 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8#include <linux/gfp.h>
9#include <linux/init.h>
10#include <linux/sched.h>
11#include "afs_fs.h"
12#include "internal.h"
13
14/*
15 * Deliver reply data to a VL.GetEntryByNameU call.
16 */
17static int afs_deliver_vl_get_entry_by_name_u(struct afs_call *call)
18{
19	struct afs_uvldbentry__xdr *uvldb;
20	struct afs_vldb_entry *entry;
21	u32 nr_servers, vlflags;
22	int i, ret;
23
24	_enter("");
25
26	ret = afs_transfer_reply(call);
27	if (ret < 0)
28		return ret;
29
30	/* unmarshall the reply once we've received all of it */
31	uvldb = call->buffer;
32	entry = call->ret_vldb;
33
34	nr_servers = ntohl(uvldb->nServers);
35	if (nr_servers > AFS_NMAXNSERVERS)
36		nr_servers = AFS_NMAXNSERVERS;
37
38	for (i = 0; i < ARRAY_SIZE(uvldb->name) - 1; i++)
39		entry->name[i] = (u8)ntohl(uvldb->name[i]);
40	entry->name[i] = 0;
41	entry->name_len = strlen(entry->name);
42
43	vlflags = ntohl(uvldb->flags);
44	for (i = 0; i < nr_servers; i++) {
45		struct afs_uuid__xdr *xdr;
46		struct afs_uuid *uuid;
47		u32 tmp = ntohl(uvldb->serverFlags[i]);
48		int j;
49		int n = entry->nr_servers;
50
51		if (tmp & AFS_VLSF_RWVOL) {
52			entry->fs_mask[n] |= AFS_VOL_VTM_RW;
53			if (vlflags & AFS_VLF_BACKEXISTS)
54				entry->fs_mask[n] |= AFS_VOL_VTM_BAK;
55		}
56		if (tmp & AFS_VLSF_ROVOL)
57			entry->fs_mask[n] |= AFS_VOL_VTM_RO;
58		if (!entry->fs_mask[n])
59			continue;
60
61		xdr = &uvldb->serverNumber[i];
62		uuid = (struct afs_uuid *)&entry->fs_server[n];
63		uuid->time_low			= xdr->time_low;
64		uuid->time_mid			= htons(ntohl(xdr->time_mid));
65		uuid->time_hi_and_version	= htons(ntohl(xdr->time_hi_and_version));
66		uuid->clock_seq_hi_and_reserved	= (u8)ntohl(xdr->clock_seq_hi_and_reserved);
67		uuid->clock_seq_low		= (u8)ntohl(xdr->clock_seq_low);
68		for (j = 0; j < 6; j++)
69			uuid->node[j] = (u8)ntohl(xdr->node[j]);
70
71		entry->vlsf_flags[n] = tmp;
72		entry->addr_version[n] = ntohl(uvldb->serverUnique[i]);
73		entry->nr_servers++;
74	}
75
76	for (i = 0; i < AFS_MAXTYPES; i++)
77		entry->vid[i] = ntohl(uvldb->volumeId[i]);
78
79	if (vlflags & AFS_VLF_RWEXISTS)
80		__set_bit(AFS_VLDB_HAS_RW, &entry->flags);
81	if (vlflags & AFS_VLF_ROEXISTS)
82		__set_bit(AFS_VLDB_HAS_RO, &entry->flags);
83	if (vlflags & AFS_VLF_BACKEXISTS)
84		__set_bit(AFS_VLDB_HAS_BAK, &entry->flags);
85
86	if (!(vlflags & (AFS_VLF_RWEXISTS | AFS_VLF_ROEXISTS | AFS_VLF_BACKEXISTS))) {
87		entry->error = -ENOMEDIUM;
88		__set_bit(AFS_VLDB_QUERY_ERROR, &entry->flags);
89	}
90
91	__set_bit(AFS_VLDB_QUERY_VALID, &entry->flags);
92	_leave(" = 0 [done]");
93	return 0;
94}
95
96/*
97 * VL.GetEntryByNameU operation type.
98 */
99static const struct afs_call_type afs_RXVLGetEntryByNameU = {
100	.name		= "VL.GetEntryByNameU",
101	.op		= afs_VL_GetEntryByNameU,
102	.deliver	= afs_deliver_vl_get_entry_by_name_u,
103	.destructor	= afs_flat_call_destructor,
104};
105
106/*
107 * Dispatch a get volume entry by name or ID operation (uuid variant).  If the
108 * volname is a decimal number then it's a volume ID not a volume name.
109 */
110struct afs_vldb_entry *afs_vl_get_entry_by_name_u(struct afs_vl_cursor *vc,
111						  const char *volname,
112						  int volnamesz)
113{
114	struct afs_vldb_entry *entry;
115	struct afs_call *call;
116	struct afs_net *net = vc->cell->net;
117	size_t reqsz, padsz;
118	__be32 *bp;
119
120	_enter("");
121
122	padsz = (4 - (volnamesz & 3)) & 3;
123	reqsz = 8 + volnamesz + padsz;
124
125	entry = kzalloc(sizeof(struct afs_vldb_entry), GFP_KERNEL);
126	if (!entry)
127		return ERR_PTR(-ENOMEM);
128
129	call = afs_alloc_flat_call(net, &afs_RXVLGetEntryByNameU, reqsz,
130				   sizeof(struct afs_uvldbentry__xdr));
131	if (!call) {
132		kfree(entry);
133		return ERR_PTR(-ENOMEM);
134	}
135
136	call->key = vc->key;
137	call->ret_vldb = entry;
138	call->max_lifespan = AFS_VL_MAX_LIFESPAN;
139	call->peer = rxrpc_kernel_get_peer(vc->alist->addrs[vc->addr_index].peer);
140	call->service_id = vc->server->service_id;
141
142	/* Marshall the parameters */
143	bp = call->request;
144	*bp++ = htonl(VLGETENTRYBYNAMEU);
145	*bp++ = htonl(volnamesz);
146	memcpy(bp, volname, volnamesz);
147	if (padsz > 0)
148		memset((void *)bp + volnamesz, 0, padsz);
149
150	trace_afs_make_vl_call(call);
151	afs_make_call(call, GFP_KERNEL);
152	afs_wait_for_call_to_complete(call);
153	vc->call_abort_code	= call->abort_code;
154	vc->call_error		= call->error;
155	vc->call_responded	= call->responded;
156	afs_put_call(call);
157	if (vc->call_error) {
158		kfree(entry);
159		return ERR_PTR(vc->call_error);
160	}
161	return entry;
162}
163
164/*
165 * Deliver reply data to a VL.GetAddrsU call.
166 *
167 *	GetAddrsU(IN ListAddrByAttributes *inaddr,
168 *		  OUT afsUUID *uuidp1,
169 *		  OUT uint32_t *uniquifier,
170 *		  OUT uint32_t *nentries,
171 *		  OUT bulkaddrs *blkaddrs);
172 */
173static int afs_deliver_vl_get_addrs_u(struct afs_call *call)
174{
175	struct afs_addr_list *alist;
176	__be32 *bp;
177	u32 uniquifier, nentries, count;
178	int i, ret;
179
180	_enter("{%u,%zu/%u}",
181	       call->unmarshall, iov_iter_count(call->iter), call->count);
182
183	switch (call->unmarshall) {
184	case 0:
185		afs_extract_to_buf(call,
186				   sizeof(struct afs_uuid__xdr) + 3 * sizeof(__be32));
187		call->unmarshall++;
188
189		/* Extract the returned uuid, uniquifier, nentries and
190		 * blkaddrs size */
191		fallthrough;
192	case 1:
193		ret = afs_extract_data(call, true);
194		if (ret < 0)
195			return ret;
196
197		bp = call->buffer + sizeof(struct afs_uuid__xdr);
198		uniquifier	= ntohl(*bp++);
199		nentries	= ntohl(*bp++);
200		count		= ntohl(*bp);
201
202		nentries = min(nentries, count);
203		alist = afs_alloc_addrlist(nentries);
204		if (!alist)
205			return -ENOMEM;
206		alist->version = uniquifier;
207		call->ret_alist = alist;
208		call->count = count;
209		call->count2 = nentries;
210		call->unmarshall++;
211
212	more_entries:
213		count = min(call->count, 4U);
214		afs_extract_to_buf(call, count * sizeof(__be32));
215
216		fallthrough;	/* and extract entries */
217	case 2:
218		ret = afs_extract_data(call, call->count > 4);
219		if (ret < 0)
220			return ret;
221
222		alist = call->ret_alist;
223		bp = call->buffer;
224		count = min(call->count, 4U);
225		for (i = 0; i < count; i++) {
226			if (alist->nr_addrs < call->count2) {
227				ret = afs_merge_fs_addr4(call->net, alist, *bp++, AFS_FS_PORT);
228				if (ret < 0)
229					return ret;
230			}
231		}
232
233		call->count -= count;
234		if (call->count > 0)
235			goto more_entries;
236		call->unmarshall++;
237		break;
238	}
239
240	_leave(" = 0 [done]");
241	return 0;
242}
243
244/*
245 * VL.GetAddrsU operation type.
246 */
247static const struct afs_call_type afs_RXVLGetAddrsU = {
248	.name		= "VL.GetAddrsU",
249	.op		= afs_VL_GetAddrsU,
250	.deliver	= afs_deliver_vl_get_addrs_u,
251	.destructor	= afs_flat_call_destructor,
252};
253
254/*
255 * Dispatch an operation to get the addresses for a server, where the server is
256 * nominated by UUID.
257 */
258struct afs_addr_list *afs_vl_get_addrs_u(struct afs_vl_cursor *vc,
259					 const uuid_t *uuid)
260{
261	struct afs_ListAddrByAttributes__xdr *r;
262	struct afs_addr_list *alist;
263	const struct afs_uuid *u = (const struct afs_uuid *)uuid;
264	struct afs_call *call;
265	struct afs_net *net = vc->cell->net;
266	__be32 *bp;
267	int i;
268
269	_enter("");
270
271	call = afs_alloc_flat_call(net, &afs_RXVLGetAddrsU,
272				   sizeof(__be32) + sizeof(struct afs_ListAddrByAttributes__xdr),
273				   sizeof(struct afs_uuid__xdr) + 3 * sizeof(__be32));
274	if (!call)
275		return ERR_PTR(-ENOMEM);
276
277	call->key = vc->key;
278	call->ret_alist = NULL;
279	call->max_lifespan = AFS_VL_MAX_LIFESPAN;
280	call->peer = rxrpc_kernel_get_peer(vc->alist->addrs[vc->addr_index].peer);
281	call->service_id = vc->server->service_id;
282
283	/* Marshall the parameters */
284	bp = call->request;
285	*bp++ = htonl(VLGETADDRSU);
286	r = (struct afs_ListAddrByAttributes__xdr *)bp;
287	r->Mask		= htonl(AFS_VLADDR_UUID);
288	r->ipaddr	= 0;
289	r->index	= 0;
290	r->spare	= 0;
291	r->uuid.time_low			= u->time_low;
292	r->uuid.time_mid			= htonl(ntohs(u->time_mid));
293	r->uuid.time_hi_and_version		= htonl(ntohs(u->time_hi_and_version));
294	r->uuid.clock_seq_hi_and_reserved 	= htonl(u->clock_seq_hi_and_reserved);
295	r->uuid.clock_seq_low			= htonl(u->clock_seq_low);
296	for (i = 0; i < 6; i++)
297		r->uuid.node[i] = htonl(u->node[i]);
298
299	trace_afs_make_vl_call(call);
300	afs_make_call(call, GFP_KERNEL);
301	afs_wait_for_call_to_complete(call);
302	vc->call_abort_code	= call->abort_code;
303	vc->call_error		= call->error;
304	vc->call_responded	= call->responded;
305	alist			= call->ret_alist;
306	afs_put_call(call);
307	if (vc->call_error) {
308		afs_put_addrlist(alist, afs_alist_trace_put_getaddru);
309		return ERR_PTR(vc->call_error);
310	}
311	return alist;
312}
313
314/*
315 * Deliver reply data to an VL.GetCapabilities operation.
316 */
317static int afs_deliver_vl_get_capabilities(struct afs_call *call)
318{
319	u32 count;
320	int ret;
321
322	_enter("{%u,%zu/%u}",
323	       call->unmarshall, iov_iter_count(call->iter), call->count);
324
325	switch (call->unmarshall) {
326	case 0:
327		afs_extract_to_tmp(call);
328		call->unmarshall++;
329
330		fallthrough;	/* and extract the capabilities word count */
331	case 1:
332		ret = afs_extract_data(call, true);
333		if (ret < 0)
334			return ret;
335
336		count = ntohl(call->tmp);
337		call->count = count;
338		call->count2 = count;
339
340		call->unmarshall++;
341		afs_extract_discard(call, count * sizeof(__be32));
342
343		fallthrough;	/* and extract capabilities words */
344	case 2:
345		ret = afs_extract_data(call, false);
346		if (ret < 0)
347			return ret;
348
349		/* TODO: Examine capabilities */
350
351		call->unmarshall++;
352		break;
353	}
354
355	_leave(" = 0 [done]");
356	return 0;
357}
358
359static void afs_destroy_vl_get_capabilities(struct afs_call *call)
360{
361	afs_put_addrlist(call->vl_probe, afs_alist_trace_put_vlgetcaps);
362	afs_put_vlserver(call->net, call->vlserver);
363	afs_flat_call_destructor(call);
364}
365
366/*
367 * VL.GetCapabilities operation type
368 */
369static const struct afs_call_type afs_RXVLGetCapabilities = {
370	.name		= "VL.GetCapabilities",
371	.op		= afs_VL_GetCapabilities,
372	.deliver	= afs_deliver_vl_get_capabilities,
373	.done		= afs_vlserver_probe_result,
374	.destructor	= afs_destroy_vl_get_capabilities,
375};
376
377/*
378 * Probe a volume server for the capabilities that it supports.  This can
379 * return up to 196 words.
380 *
381 * We use this to probe for service upgrade to determine what the server at the
382 * other end supports.
383 */
384struct afs_call *afs_vl_get_capabilities(struct afs_net *net,
385					 struct afs_addr_list *alist,
386					 unsigned int addr_index,
387					 struct key *key,
388					 struct afs_vlserver *server,
389					 unsigned int server_index)
390{
391	struct afs_call *call;
392	__be32 *bp;
393
394	_enter("");
395
396	call = afs_alloc_flat_call(net, &afs_RXVLGetCapabilities, 1 * 4, 16 * 4);
397	if (!call)
398		return ERR_PTR(-ENOMEM);
399
400	call->key = key;
401	call->vlserver = afs_get_vlserver(server);
402	call->server_index = server_index;
403	call->peer = rxrpc_kernel_get_peer(alist->addrs[addr_index].peer);
404	call->vl_probe = afs_get_addrlist(alist, afs_alist_trace_get_vlgetcaps);
405	call->probe_index = addr_index;
406	call->service_id = server->service_id;
407	call->upgrade = true;
408	call->async = true;
409	call->max_lifespan = AFS_PROBE_MAX_LIFESPAN;
410
411	/* marshall the parameters */
412	bp = call->request;
413	*bp++ = htonl(VLGETCAPABILITIES);
414
415	/* Can't take a ref on server */
416	trace_afs_make_vl_call(call);
417	afs_make_call(call, GFP_KERNEL);
418	return call;
419}
420
421/*
422 * Deliver reply data to a YFSVL.GetEndpoints call.
423 *
424 *	GetEndpoints(IN yfsServerAttributes *attr,
425 *		     OUT opr_uuid *uuid,
426 *		     OUT afs_int32 *uniquifier,
427 *		     OUT endpoints *fsEndpoints,
428 *		     OUT endpoints *volEndpoints)
429 */
430static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
431{
432	struct afs_addr_list *alist;
433	__be32 *bp;
434	u32 uniquifier, size;
435	int ret;
436
437	_enter("{%u,%zu,%u}",
438	       call->unmarshall, iov_iter_count(call->iter), call->count2);
439
440	switch (call->unmarshall) {
441	case 0:
442		afs_extract_to_buf(call, sizeof(uuid_t) + 3 * sizeof(__be32));
443		call->unmarshall = 1;
444
445		/* Extract the returned uuid, uniquifier, fsEndpoints count and
446		 * either the first fsEndpoint type or the volEndpoints
447		 * count if there are no fsEndpoints. */
448		fallthrough;
449	case 1:
450		ret = afs_extract_data(call, true);
451		if (ret < 0)
452			return ret;
453
454		bp = call->buffer + sizeof(uuid_t);
455		uniquifier	= ntohl(*bp++);
456		call->count	= ntohl(*bp++);
457		call->count2	= ntohl(*bp); /* Type or next count */
458
459		if (call->count > YFS_MAXENDPOINTS)
460			return afs_protocol_error(call, afs_eproto_yvl_fsendpt_num);
461
462		alist = afs_alloc_addrlist(call->count);
463		if (!alist)
464			return -ENOMEM;
465		alist->version = uniquifier;
466		call->ret_alist = alist;
467
468		if (call->count == 0)
469			goto extract_volendpoints;
470
471	next_fsendpoint:
472		switch (call->count2) {
473		case YFS_ENDPOINT_IPV4:
474			size = sizeof(__be32) * (1 + 1 + 1);
475			break;
476		case YFS_ENDPOINT_IPV6:
477			size = sizeof(__be32) * (1 + 4 + 1);
478			break;
479		default:
480			return afs_protocol_error(call, afs_eproto_yvl_fsendpt_type);
481		}
482
483		size += sizeof(__be32);
484		afs_extract_to_buf(call, size);
485		call->unmarshall = 2;
486
487		fallthrough;	/* and extract fsEndpoints[] entries */
488	case 2:
489		ret = afs_extract_data(call, true);
490		if (ret < 0)
491			return ret;
492
493		alist = call->ret_alist;
494		bp = call->buffer;
495		switch (call->count2) {
496		case YFS_ENDPOINT_IPV4:
497			if (ntohl(bp[0]) != sizeof(__be32) * 2)
498				return afs_protocol_error(
499					call, afs_eproto_yvl_fsendpt4_len);
500			ret = afs_merge_fs_addr4(call->net, alist, bp[1], ntohl(bp[2]));
501			if (ret < 0)
502				return ret;
503			bp += 3;
504			break;
505		case YFS_ENDPOINT_IPV6:
506			if (ntohl(bp[0]) != sizeof(__be32) * 5)
507				return afs_protocol_error(
508					call, afs_eproto_yvl_fsendpt6_len);
509			ret = afs_merge_fs_addr6(call->net, alist, bp + 1, ntohl(bp[5]));
510			if (ret < 0)
511				return ret;
512			bp += 6;
513			break;
514		default:
515			return afs_protocol_error(call, afs_eproto_yvl_fsendpt_type);
516		}
517
518		/* Got either the type of the next entry or the count of
519		 * volEndpoints if no more fsEndpoints.
520		 */
521		call->count2 = ntohl(*bp++);
522
523		call->count--;
524		if (call->count > 0)
525			goto next_fsendpoint;
526
527	extract_volendpoints:
528		/* Extract the list of volEndpoints. */
529		call->count = call->count2;
530		if (!call->count)
531			goto end;
532		if (call->count > YFS_MAXENDPOINTS)
533			return afs_protocol_error(call, afs_eproto_yvl_vlendpt_type);
534
535		afs_extract_to_buf(call, 1 * sizeof(__be32));
536		call->unmarshall = 3;
537
538		/* Extract the type of volEndpoints[0].  Normally we would
539		 * extract the type of the next endpoint when we extract the
540		 * data of the current one, but this is the first...
541		 */
542		fallthrough;
543	case 3:
544		ret = afs_extract_data(call, true);
545		if (ret < 0)
546			return ret;
547
548		bp = call->buffer;
549
550	next_volendpoint:
551		call->count2 = ntohl(*bp++);
552		switch (call->count2) {
553		case YFS_ENDPOINT_IPV4:
554			size = sizeof(__be32) * (1 + 1 + 1);
555			break;
556		case YFS_ENDPOINT_IPV6:
557			size = sizeof(__be32) * (1 + 4 + 1);
558			break;
559		default:
560			return afs_protocol_error(call, afs_eproto_yvl_vlendpt_type);
561		}
562
563		if (call->count > 1)
564			size += sizeof(__be32); /* Get next type too */
565		afs_extract_to_buf(call, size);
566		call->unmarshall = 4;
567
568		fallthrough;	/* and extract volEndpoints[] entries */
569	case 4:
570		ret = afs_extract_data(call, true);
571		if (ret < 0)
572			return ret;
573
574		bp = call->buffer;
575		switch (call->count2) {
576		case YFS_ENDPOINT_IPV4:
577			if (ntohl(bp[0]) != sizeof(__be32) * 2)
578				return afs_protocol_error(
579					call, afs_eproto_yvl_vlendpt4_len);
580			bp += 3;
581			break;
582		case YFS_ENDPOINT_IPV6:
583			if (ntohl(bp[0]) != sizeof(__be32) * 5)
584				return afs_protocol_error(
585					call, afs_eproto_yvl_vlendpt6_len);
586			bp += 6;
587			break;
588		default:
589			return afs_protocol_error(call, afs_eproto_yvl_vlendpt_type);
590		}
591
592		/* Got either the type of the next entry or the count of
593		 * volEndpoints if no more fsEndpoints.
594		 */
595		call->count--;
596		if (call->count > 0)
597			goto next_volendpoint;
598
599	end:
600		afs_extract_discard(call, 0);
601		call->unmarshall = 5;
602
603		fallthrough;	/* Done */
604	case 5:
605		ret = afs_extract_data(call, false);
606		if (ret < 0)
607			return ret;
608		call->unmarshall = 6;
609		fallthrough;
610
611	case 6:
612		break;
613	}
614
615	_leave(" = 0 [done]");
616	return 0;
617}
618
619/*
620 * YFSVL.GetEndpoints operation type.
621 */
622static const struct afs_call_type afs_YFSVLGetEndpoints = {
623	.name		= "YFSVL.GetEndpoints",
624	.op		= afs_YFSVL_GetEndpoints,
625	.deliver	= afs_deliver_yfsvl_get_endpoints,
626	.destructor	= afs_flat_call_destructor,
627};
628
629/*
630 * Dispatch an operation to get the addresses for a server, where the server is
631 * nominated by UUID.
632 */
633struct afs_addr_list *afs_yfsvl_get_endpoints(struct afs_vl_cursor *vc,
634					      const uuid_t *uuid)
635{
636	struct afs_addr_list *alist;
637	struct afs_call *call;
638	struct afs_net *net = vc->cell->net;
639	__be32 *bp;
640
641	_enter("");
642
643	call = afs_alloc_flat_call(net, &afs_YFSVLGetEndpoints,
644				   sizeof(__be32) * 2 + sizeof(*uuid),
645				   sizeof(struct in6_addr) + sizeof(__be32) * 3);
646	if (!call)
647		return ERR_PTR(-ENOMEM);
648
649	call->key = vc->key;
650	call->ret_alist = NULL;
651	call->max_lifespan = AFS_VL_MAX_LIFESPAN;
652	call->peer = rxrpc_kernel_get_peer(vc->alist->addrs[vc->addr_index].peer);
653	call->service_id = vc->server->service_id;
654
655	/* Marshall the parameters */
656	bp = call->request;
657	*bp++ = htonl(YVLGETENDPOINTS);
658	*bp++ = htonl(YFS_SERVER_UUID);
659	memcpy(bp, uuid, sizeof(*uuid)); /* Type opr_uuid */
660
661	trace_afs_make_vl_call(call);
662	afs_make_call(call, GFP_KERNEL);
663	afs_wait_for_call_to_complete(call);
664	vc->call_abort_code	= call->abort_code;
665	vc->call_error		= call->error;
666	vc->call_responded	= call->responded;
667	alist			= call->ret_alist;
668	afs_put_call(call);
669	if (vc->call_error) {
670		afs_put_addrlist(alist, afs_alist_trace_put_getaddru);
671		return ERR_PTR(vc->call_error);
672	}
673	return alist;
674}
675
676/*
677 * Deliver reply data to a YFSVL.GetCellName operation.
678 */
679static int afs_deliver_yfsvl_get_cell_name(struct afs_call *call)
680{
681	char *cell_name;
682	u32 namesz, paddedsz;
683	int ret;
684
685	_enter("{%u,%zu/%u}",
686	       call->unmarshall, iov_iter_count(call->iter), call->count);
687
688	switch (call->unmarshall) {
689	case 0:
690		afs_extract_to_tmp(call);
691		call->unmarshall++;
692
693		fallthrough;	/* and extract the cell name length */
694	case 1:
695		ret = afs_extract_data(call, true);
696		if (ret < 0)
697			return ret;
698
699		namesz = ntohl(call->tmp);
700		if (namesz > AFS_MAXCELLNAME)
701			return afs_protocol_error(call, afs_eproto_cellname_len);
702		paddedsz = (namesz + 3) & ~3;
703		call->count = namesz;
704		call->count2 = paddedsz - namesz;
705
706		cell_name = kmalloc(namesz + 1, GFP_KERNEL);
707		if (!cell_name)
708			return -ENOMEM;
709		cell_name[namesz] = 0;
710		call->ret_str = cell_name;
711
712		afs_extract_begin(call, cell_name, namesz);
713		call->unmarshall++;
714
715		fallthrough;	/* and extract cell name */
716	case 2:
717		ret = afs_extract_data(call, true);
718		if (ret < 0)
719			return ret;
720
721		afs_extract_discard(call, call->count2);
722		call->unmarshall++;
723
724		fallthrough;	/* and extract padding */
725	case 3:
726		ret = afs_extract_data(call, false);
727		if (ret < 0)
728			return ret;
729
730		call->unmarshall++;
731		break;
732	}
733
734	_leave(" = 0 [done]");
735	return 0;
736}
737
738/*
739 * VL.GetCapabilities operation type
740 */
741static const struct afs_call_type afs_YFSVLGetCellName = {
742	.name		= "YFSVL.GetCellName",
743	.op		= afs_YFSVL_GetCellName,
744	.deliver	= afs_deliver_yfsvl_get_cell_name,
745	.destructor	= afs_flat_call_destructor,
746};
747
748/*
749 * Probe a volume server for the capabilities that it supports.  This can
750 * return up to 196 words.
751 *
752 * We use this to probe for service upgrade to determine what the server at the
753 * other end supports.
754 */
755char *afs_yfsvl_get_cell_name(struct afs_vl_cursor *vc)
756{
757	struct afs_call *call;
758	struct afs_net *net = vc->cell->net;
759	__be32 *bp;
760	char *cellname;
761
762	_enter("");
763
764	call = afs_alloc_flat_call(net, &afs_YFSVLGetCellName, 1 * 4, 0);
765	if (!call)
766		return ERR_PTR(-ENOMEM);
767
768	call->key = vc->key;
769	call->ret_str = NULL;
770	call->max_lifespan = AFS_VL_MAX_LIFESPAN;
771	call->peer = rxrpc_kernel_get_peer(vc->alist->addrs[vc->addr_index].peer);
772	call->service_id = vc->server->service_id;
773
774	/* marshall the parameters */
775	bp = call->request;
776	*bp++ = htonl(YVLGETCELLNAME);
777
778	/* Can't take a ref on server */
779	trace_afs_make_vl_call(call);
780	afs_make_call(call, GFP_KERNEL);
781	afs_wait_for_call_to_complete(call);
782	vc->call_abort_code	= call->abort_code;
783	vc->call_error		= call->error;
784	vc->call_responded	= call->responded;
785	cellname		= call->ret_str;
786	afs_put_call(call);
787	if (vc->call_error) {
788		kfree(cellname);
789		return ERR_PTR(vc->call_error);
790	}
791	return cellname;
792}
793