xref: /openbmc/linux/fs/nfs/client.c (revision bc5aa3a0)
1 /* client.c: NFS client sharing and management code
2  *
3  * Copyright (C) 2006 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 
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/sched.h>
16 #include <linux/time.h>
17 #include <linux/kernel.h>
18 #include <linux/mm.h>
19 #include <linux/string.h>
20 #include <linux/stat.h>
21 #include <linux/errno.h>
22 #include <linux/unistd.h>
23 #include <linux/sunrpc/addr.h>
24 #include <linux/sunrpc/clnt.h>
25 #include <linux/sunrpc/stats.h>
26 #include <linux/sunrpc/metrics.h>
27 #include <linux/sunrpc/xprtsock.h>
28 #include <linux/sunrpc/xprtrdma.h>
29 #include <linux/nfs_fs.h>
30 #include <linux/nfs_mount.h>
31 #include <linux/nfs4_mount.h>
32 #include <linux/lockd/bind.h>
33 #include <linux/seq_file.h>
34 #include <linux/mount.h>
35 #include <linux/vfs.h>
36 #include <linux/inet.h>
37 #include <linux/in6.h>
38 #include <linux/slab.h>
39 #include <linux/idr.h>
40 #include <net/ipv6.h>
41 #include <linux/nfs_xdr.h>
42 #include <linux/sunrpc/bc_xprt.h>
43 #include <linux/nsproxy.h>
44 #include <linux/pid_namespace.h>
45 
46 
47 #include "nfs4_fs.h"
48 #include "callback.h"
49 #include "delegation.h"
50 #include "iostat.h"
51 #include "internal.h"
52 #include "fscache.h"
53 #include "pnfs.h"
54 #include "nfs.h"
55 #include "netns.h"
56 
57 #define NFSDBG_FACILITY		NFSDBG_CLIENT
58 
59 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
60 static DEFINE_SPINLOCK(nfs_version_lock);
61 static DEFINE_MUTEX(nfs_version_mutex);
62 static LIST_HEAD(nfs_versions);
63 
64 /*
65  * RPC cruft for NFS
66  */
67 static const struct rpc_version *nfs_version[5] = {
68 	[2] = NULL,
69 	[3] = NULL,
70 	[4] = NULL,
71 };
72 
73 const struct rpc_program nfs_program = {
74 	.name			= "nfs",
75 	.number			= NFS_PROGRAM,
76 	.nrvers			= ARRAY_SIZE(nfs_version),
77 	.version		= nfs_version,
78 	.stats			= &nfs_rpcstat,
79 	.pipe_dir_name		= NFS_PIPE_DIRNAME,
80 };
81 
82 struct rpc_stat nfs_rpcstat = {
83 	.program		= &nfs_program
84 };
85 
86 static struct nfs_subversion *find_nfs_version(unsigned int version)
87 {
88 	struct nfs_subversion *nfs;
89 	spin_lock(&nfs_version_lock);
90 
91 	list_for_each_entry(nfs, &nfs_versions, list) {
92 		if (nfs->rpc_ops->version == version) {
93 			spin_unlock(&nfs_version_lock);
94 			return nfs;
95 		}
96 	}
97 
98 	spin_unlock(&nfs_version_lock);
99 	return ERR_PTR(-EPROTONOSUPPORT);
100 }
101 
102 struct nfs_subversion *get_nfs_version(unsigned int version)
103 {
104 	struct nfs_subversion *nfs = find_nfs_version(version);
105 
106 	if (IS_ERR(nfs)) {
107 		mutex_lock(&nfs_version_mutex);
108 		request_module("nfsv%d", version);
109 		nfs = find_nfs_version(version);
110 		mutex_unlock(&nfs_version_mutex);
111 	}
112 
113 	if (!IS_ERR(nfs) && !try_module_get(nfs->owner))
114 		return ERR_PTR(-EAGAIN);
115 	return nfs;
116 }
117 
118 void put_nfs_version(struct nfs_subversion *nfs)
119 {
120 	module_put(nfs->owner);
121 }
122 
123 void register_nfs_version(struct nfs_subversion *nfs)
124 {
125 	spin_lock(&nfs_version_lock);
126 
127 	list_add(&nfs->list, &nfs_versions);
128 	nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
129 
130 	spin_unlock(&nfs_version_lock);
131 }
132 EXPORT_SYMBOL_GPL(register_nfs_version);
133 
134 void unregister_nfs_version(struct nfs_subversion *nfs)
135 {
136 	spin_lock(&nfs_version_lock);
137 
138 	nfs_version[nfs->rpc_ops->version] = NULL;
139 	list_del(&nfs->list);
140 
141 	spin_unlock(&nfs_version_lock);
142 }
143 EXPORT_SYMBOL_GPL(unregister_nfs_version);
144 
145 /*
146  * Allocate a shared client record
147  *
148  * Since these are allocated/deallocated very rarely, we don't
149  * bother putting them in a slab cache...
150  */
151 struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
152 {
153 	struct nfs_client *clp;
154 	struct rpc_cred *cred;
155 	int err = -ENOMEM;
156 
157 	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
158 		goto error_0;
159 
160 	clp->cl_nfs_mod = cl_init->nfs_mod;
161 	if (!try_module_get(clp->cl_nfs_mod->owner))
162 		goto error_dealloc;
163 
164 	clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
165 
166 	atomic_set(&clp->cl_count, 1);
167 	clp->cl_cons_state = NFS_CS_INITING;
168 
169 	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
170 	clp->cl_addrlen = cl_init->addrlen;
171 
172 	if (cl_init->hostname) {
173 		err = -ENOMEM;
174 		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
175 		if (!clp->cl_hostname)
176 			goto error_cleanup;
177 	}
178 
179 	INIT_LIST_HEAD(&clp->cl_superblocks);
180 	clp->cl_rpcclient = ERR_PTR(-EINVAL);
181 
182 	clp->cl_proto = cl_init->proto;
183 	clp->cl_net = get_net(cl_init->net);
184 
185 	cred = rpc_lookup_machine_cred("*");
186 	if (!IS_ERR(cred))
187 		clp->cl_machine_cred = cred;
188 	nfs_fscache_get_client_cookie(clp);
189 
190 	return clp;
191 
192 error_cleanup:
193 	put_nfs_version(clp->cl_nfs_mod);
194 error_dealloc:
195 	kfree(clp);
196 error_0:
197 	return ERR_PTR(err);
198 }
199 EXPORT_SYMBOL_GPL(nfs_alloc_client);
200 
201 #if IS_ENABLED(CONFIG_NFS_V4)
202 void nfs_cleanup_cb_ident_idr(struct net *net)
203 {
204 	struct nfs_net *nn = net_generic(net, nfs_net_id);
205 
206 	idr_destroy(&nn->cb_ident_idr);
207 }
208 
209 /* nfs_client_lock held */
210 static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
211 {
212 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
213 
214 	if (clp->cl_cb_ident)
215 		idr_remove(&nn->cb_ident_idr, clp->cl_cb_ident);
216 }
217 
218 static void pnfs_init_server(struct nfs_server *server)
219 {
220 	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
221 }
222 
223 #else
224 void nfs_cleanup_cb_ident_idr(struct net *net)
225 {
226 }
227 
228 static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
229 {
230 }
231 
232 static void pnfs_init_server(struct nfs_server *server)
233 {
234 }
235 
236 #endif /* CONFIG_NFS_V4 */
237 
238 /*
239  * Destroy a shared client record
240  */
241 void nfs_free_client(struct nfs_client *clp)
242 {
243 	dprintk("--> nfs_free_client(%u)\n", clp->rpc_ops->version);
244 
245 	nfs_fscache_release_client_cookie(clp);
246 
247 	/* -EIO all pending I/O */
248 	if (!IS_ERR(clp->cl_rpcclient))
249 		rpc_shutdown_client(clp->cl_rpcclient);
250 
251 	if (clp->cl_machine_cred != NULL)
252 		put_rpccred(clp->cl_machine_cred);
253 
254 	put_net(clp->cl_net);
255 	put_nfs_version(clp->cl_nfs_mod);
256 	kfree(clp->cl_hostname);
257 	kfree(clp->cl_acceptor);
258 	kfree(clp);
259 
260 	dprintk("<-- nfs_free_client()\n");
261 }
262 EXPORT_SYMBOL_GPL(nfs_free_client);
263 
264 /*
265  * Release a reference to a shared client record
266  */
267 void nfs_put_client(struct nfs_client *clp)
268 {
269 	struct nfs_net *nn;
270 
271 	if (!clp)
272 		return;
273 
274 	dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
275 	nn = net_generic(clp->cl_net, nfs_net_id);
276 
277 	if (atomic_dec_and_lock(&clp->cl_count, &nn->nfs_client_lock)) {
278 		list_del(&clp->cl_share_link);
279 		nfs_cb_idr_remove_locked(clp);
280 		spin_unlock(&nn->nfs_client_lock);
281 
282 		WARN_ON_ONCE(!list_empty(&clp->cl_superblocks));
283 
284 		clp->rpc_ops->free_client(clp);
285 	}
286 }
287 EXPORT_SYMBOL_GPL(nfs_put_client);
288 
289 /*
290  * Find an nfs_client on the list that matches the initialisation data
291  * that is supplied.
292  */
293 static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
294 {
295 	struct nfs_client *clp;
296 	const struct sockaddr *sap = data->addr;
297 	struct nfs_net *nn = net_generic(data->net, nfs_net_id);
298 
299 	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
300 	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
301 		/* Don't match clients that failed to initialise properly */
302 		if (clp->cl_cons_state < 0)
303 			continue;
304 
305 		/* Different NFS versions cannot share the same nfs_client */
306 		if (clp->rpc_ops != data->nfs_mod->rpc_ops)
307 			continue;
308 
309 		if (clp->cl_proto != data->proto)
310 			continue;
311 		/* Match nfsv4 minorversion */
312 		if (clp->cl_minorversion != data->minorversion)
313 			continue;
314 		/* Match the full socket address */
315 		if (!rpc_cmp_addr_port(sap, clap))
316 			continue;
317 
318 		atomic_inc(&clp->cl_count);
319 		return clp;
320 	}
321 	return NULL;
322 }
323 
324 static bool nfs_client_init_is_complete(const struct nfs_client *clp)
325 {
326 	return clp->cl_cons_state <= NFS_CS_READY;
327 }
328 
329 int nfs_wait_client_init_complete(const struct nfs_client *clp)
330 {
331 	return wait_event_killable(nfs_client_active_wq,
332 			nfs_client_init_is_complete(clp));
333 }
334 EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
335 
336 /*
337  * Found an existing client.  Make sure it's ready before returning.
338  */
339 static struct nfs_client *
340 nfs_found_client(const struct nfs_client_initdata *cl_init,
341 		 struct nfs_client *clp)
342 {
343 	int error;
344 
345 	error = nfs_wait_client_init_complete(clp);
346 	if (error < 0) {
347 		nfs_put_client(clp);
348 		return ERR_PTR(-ERESTARTSYS);
349 	}
350 
351 	if (clp->cl_cons_state < NFS_CS_READY) {
352 		error = clp->cl_cons_state;
353 		nfs_put_client(clp);
354 		return ERR_PTR(error);
355 	}
356 
357 	smp_rmb();
358 
359 	dprintk("<-- %s found nfs_client %p for %s\n",
360 		__func__, clp, cl_init->hostname ?: "");
361 	return clp;
362 }
363 
364 /*
365  * Look up a client by IP address and protocol version
366  * - creates a new record if one doesn't yet exist
367  */
368 struct nfs_client *
369 nfs_get_client(const struct nfs_client_initdata *cl_init,
370 	       rpc_authflavor_t authflavour)
371 {
372 	struct nfs_client *clp, *new = NULL;
373 	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
374 	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
375 
376 	if (cl_init->hostname == NULL) {
377 		WARN_ON(1);
378 		return NULL;
379 	}
380 
381 	dprintk("--> nfs_get_client(%s,v%u)\n",
382 		cl_init->hostname, rpc_ops->version);
383 
384 	/* see if the client already exists */
385 	do {
386 		spin_lock(&nn->nfs_client_lock);
387 
388 		clp = nfs_match_client(cl_init);
389 		if (clp) {
390 			spin_unlock(&nn->nfs_client_lock);
391 			if (new)
392 				new->rpc_ops->free_client(new);
393 			return nfs_found_client(cl_init, clp);
394 		}
395 		if (new) {
396 			list_add_tail(&new->cl_share_link,
397 					&nn->nfs_client_list);
398 			spin_unlock(&nn->nfs_client_lock);
399 			new->cl_flags = cl_init->init_flags;
400 			return rpc_ops->init_client(new, cl_init);
401 		}
402 
403 		spin_unlock(&nn->nfs_client_lock);
404 
405 		new = rpc_ops->alloc_client(cl_init);
406 	} while (!IS_ERR(new));
407 
408 	dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
409 		cl_init->hostname, PTR_ERR(new));
410 	return new;
411 }
412 EXPORT_SYMBOL_GPL(nfs_get_client);
413 
414 /*
415  * Mark a server as ready or failed
416  */
417 void nfs_mark_client_ready(struct nfs_client *clp, int state)
418 {
419 	smp_wmb();
420 	clp->cl_cons_state = state;
421 	wake_up_all(&nfs_client_active_wq);
422 }
423 EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
424 
425 /*
426  * Initialise the timeout values for a connection
427  */
428 void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
429 				    int timeo, int retrans)
430 {
431 	to->to_initval = timeo * HZ / 10;
432 	to->to_retries = retrans;
433 
434 	switch (proto) {
435 	case XPRT_TRANSPORT_TCP:
436 	case XPRT_TRANSPORT_RDMA:
437 		if (retrans == NFS_UNSPEC_RETRANS)
438 			to->to_retries = NFS_DEF_TCP_RETRANS;
439 		if (timeo == NFS_UNSPEC_TIMEO || to->to_retries == 0)
440 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
441 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
442 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
443 		to->to_increment = to->to_initval;
444 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
445 		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
446 			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
447 		if (to->to_maxval < to->to_initval)
448 			to->to_maxval = to->to_initval;
449 		to->to_exponential = 0;
450 		break;
451 	case XPRT_TRANSPORT_UDP:
452 		if (retrans == NFS_UNSPEC_RETRANS)
453 			to->to_retries = NFS_DEF_UDP_RETRANS;
454 		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
455 			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
456 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
457 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
458 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
459 		to->to_exponential = 1;
460 		break;
461 	default:
462 		BUG();
463 	}
464 }
465 EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
466 
467 /*
468  * Create an RPC client handle
469  */
470 int nfs_create_rpc_client(struct nfs_client *clp,
471 			  const struct nfs_client_initdata *cl_init,
472 			  rpc_authflavor_t flavor)
473 {
474 	struct rpc_clnt		*clnt = NULL;
475 	struct rpc_create_args args = {
476 		.net		= clp->cl_net,
477 		.protocol	= clp->cl_proto,
478 		.address	= (struct sockaddr *)&clp->cl_addr,
479 		.addrsize	= clp->cl_addrlen,
480 		.timeout	= cl_init->timeparms,
481 		.servername	= clp->cl_hostname,
482 		.nodename	= cl_init->nodename,
483 		.program	= &nfs_program,
484 		.version	= clp->rpc_ops->version,
485 		.authflavor	= flavor,
486 	};
487 
488 	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
489 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
490 	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
491 		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
492 	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
493 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
494 	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
495 		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
496 
497 	if (!IS_ERR(clp->cl_rpcclient))
498 		return 0;
499 
500 	clnt = rpc_create(&args);
501 	if (IS_ERR(clnt)) {
502 		dprintk("%s: cannot create RPC client. Error = %ld\n",
503 				__func__, PTR_ERR(clnt));
504 		return PTR_ERR(clnt);
505 	}
506 
507 	clp->cl_rpcclient = clnt;
508 	return 0;
509 }
510 EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
511 
512 /*
513  * Version 2 or 3 client destruction
514  */
515 static void nfs_destroy_server(struct nfs_server *server)
516 {
517 	if (server->nlm_host)
518 		nlmclnt_done(server->nlm_host);
519 }
520 
521 /*
522  * Version 2 or 3 lockd setup
523  */
524 static int nfs_start_lockd(struct nfs_server *server)
525 {
526 	struct nlm_host *host;
527 	struct nfs_client *clp = server->nfs_client;
528 	struct nlmclnt_initdata nlm_init = {
529 		.hostname	= clp->cl_hostname,
530 		.address	= (struct sockaddr *)&clp->cl_addr,
531 		.addrlen	= clp->cl_addrlen,
532 		.nfs_version	= clp->rpc_ops->version,
533 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
534 					1 : 0,
535 		.net		= clp->cl_net,
536 	};
537 
538 	if (nlm_init.nfs_version > 3)
539 		return 0;
540 	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
541 			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
542 		return 0;
543 
544 	switch (clp->cl_proto) {
545 		default:
546 			nlm_init.protocol = IPPROTO_TCP;
547 			break;
548 		case XPRT_TRANSPORT_UDP:
549 			nlm_init.protocol = IPPROTO_UDP;
550 	}
551 
552 	host = nlmclnt_init(&nlm_init);
553 	if (IS_ERR(host))
554 		return PTR_ERR(host);
555 
556 	server->nlm_host = host;
557 	server->destroy = nfs_destroy_server;
558 	return 0;
559 }
560 
561 /*
562  * Create a general RPC client
563  */
564 int nfs_init_server_rpcclient(struct nfs_server *server,
565 		const struct rpc_timeout *timeo,
566 		rpc_authflavor_t pseudoflavour)
567 {
568 	struct nfs_client *clp = server->nfs_client;
569 
570 	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
571 							pseudoflavour);
572 	if (IS_ERR(server->client)) {
573 		dprintk("%s: couldn't create rpc_client!\n", __func__);
574 		return PTR_ERR(server->client);
575 	}
576 
577 	memcpy(&server->client->cl_timeout_default,
578 			timeo,
579 			sizeof(server->client->cl_timeout_default));
580 	server->client->cl_timeout = &server->client->cl_timeout_default;
581 	server->client->cl_softrtry = 0;
582 	if (server->flags & NFS_MOUNT_SOFT)
583 		server->client->cl_softrtry = 1;
584 
585 	return 0;
586 }
587 EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
588 
589 /**
590  * nfs_init_client - Initialise an NFS2 or NFS3 client
591  *
592  * @clp: nfs_client to initialise
593  * @cl_init: Initialisation parameters
594  *
595  * Returns pointer to an NFS client, or an ERR_PTR value.
596  */
597 struct nfs_client *nfs_init_client(struct nfs_client *clp,
598 				   const struct nfs_client_initdata *cl_init)
599 {
600 	int error;
601 
602 	if (clp->cl_cons_state == NFS_CS_READY) {
603 		/* the client is already initialised */
604 		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
605 		return clp;
606 	}
607 
608 	/*
609 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
610 	 * - RFC 2623, sec 2.3.2
611 	 */
612 	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
613 	if (error < 0)
614 		goto error;
615 	nfs_mark_client_ready(clp, NFS_CS_READY);
616 	return clp;
617 
618 error:
619 	nfs_mark_client_ready(clp, error);
620 	nfs_put_client(clp);
621 	dprintk("<-- nfs_init_client() = xerror %d\n", error);
622 	return ERR_PTR(error);
623 }
624 EXPORT_SYMBOL_GPL(nfs_init_client);
625 
626 /*
627  * Create a version 2 or 3 client
628  */
629 static int nfs_init_server(struct nfs_server *server,
630 			   const struct nfs_parsed_mount_data *data,
631 			   struct nfs_subversion *nfs_mod)
632 {
633 	struct rpc_timeout timeparms;
634 	struct nfs_client_initdata cl_init = {
635 		.hostname = data->nfs_server.hostname,
636 		.addr = (const struct sockaddr *)&data->nfs_server.address,
637 		.addrlen = data->nfs_server.addrlen,
638 		.nfs_mod = nfs_mod,
639 		.proto = data->nfs_server.protocol,
640 		.net = data->net,
641 		.timeparms = &timeparms,
642 	};
643 	struct nfs_client *clp;
644 	int error;
645 
646 	dprintk("--> nfs_init_server()\n");
647 
648 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
649 			data->timeo, data->retrans);
650 	if (data->flags & NFS_MOUNT_NORESVPORT)
651 		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
652 
653 	/* Allocate or find a client reference we can use */
654 	clp = nfs_get_client(&cl_init, RPC_AUTH_UNIX);
655 	if (IS_ERR(clp)) {
656 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
657 		return PTR_ERR(clp);
658 	}
659 
660 	server->nfs_client = clp;
661 
662 	/* Initialise the client representation from the mount data */
663 	server->flags = data->flags;
664 	server->options = data->options;
665 	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
666 		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
667 		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
668 
669 	if (data->rsize)
670 		server->rsize = nfs_block_size(data->rsize, NULL);
671 	if (data->wsize)
672 		server->wsize = nfs_block_size(data->wsize, NULL);
673 
674 	server->acregmin = data->acregmin * HZ;
675 	server->acregmax = data->acregmax * HZ;
676 	server->acdirmin = data->acdirmin * HZ;
677 	server->acdirmax = data->acdirmax * HZ;
678 
679 	/* Start lockd here, before we might error out */
680 	error = nfs_start_lockd(server);
681 	if (error < 0)
682 		goto error;
683 
684 	server->port = data->nfs_server.port;
685 	server->auth_info = data->auth_info;
686 
687 	error = nfs_init_server_rpcclient(server, &timeparms,
688 					  data->selected_flavor);
689 	if (error < 0)
690 		goto error;
691 
692 	/* Preserve the values of mount_server-related mount options */
693 	if (data->mount_server.addrlen) {
694 		memcpy(&server->mountd_address, &data->mount_server.address,
695 			data->mount_server.addrlen);
696 		server->mountd_addrlen = data->mount_server.addrlen;
697 	}
698 	server->mountd_version = data->mount_server.version;
699 	server->mountd_port = data->mount_server.port;
700 	server->mountd_protocol = data->mount_server.protocol;
701 
702 	server->namelen  = data->namlen;
703 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
704 	return 0;
705 
706 error:
707 	server->nfs_client = NULL;
708 	nfs_put_client(clp);
709 	dprintk("<-- nfs_init_server() = xerror %d\n", error);
710 	return error;
711 }
712 
713 /*
714  * Load up the server record from information gained in an fsinfo record
715  */
716 static void nfs_server_set_fsinfo(struct nfs_server *server,
717 				  struct nfs_fsinfo *fsinfo)
718 {
719 	unsigned long max_rpc_payload;
720 
721 	/* Work out a lot of parameters */
722 	if (server->rsize == 0)
723 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
724 	if (server->wsize == 0)
725 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
726 
727 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
728 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
729 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
730 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
731 
732 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
733 	if (server->rsize > max_rpc_payload)
734 		server->rsize = max_rpc_payload;
735 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
736 		server->rsize = NFS_MAX_FILE_IO_SIZE;
737 	server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
738 
739 	server->backing_dev_info.name = "nfs";
740 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
741 
742 	if (server->wsize > max_rpc_payload)
743 		server->wsize = max_rpc_payload;
744 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
745 		server->wsize = NFS_MAX_FILE_IO_SIZE;
746 	server->wpages = (server->wsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
747 
748 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
749 
750 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
751 	if (server->dtsize > PAGE_SIZE * NFS_MAX_READDIR_PAGES)
752 		server->dtsize = PAGE_SIZE * NFS_MAX_READDIR_PAGES;
753 	if (server->dtsize > server->rsize)
754 		server->dtsize = server->rsize;
755 
756 	if (server->flags & NFS_MOUNT_NOAC) {
757 		server->acregmin = server->acregmax = 0;
758 		server->acdirmin = server->acdirmax = 0;
759 	}
760 
761 	server->maxfilesize = fsinfo->maxfilesize;
762 
763 	server->time_delta = fsinfo->time_delta;
764 
765 	server->clone_blksize = fsinfo->clone_blksize;
766 	/* We're airborne Set socket buffersize */
767 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
768 }
769 
770 /*
771  * Probe filesystem information, including the FSID on v2/v3
772  */
773 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
774 {
775 	struct nfs_fsinfo fsinfo;
776 	struct nfs_client *clp = server->nfs_client;
777 	int error;
778 
779 	dprintk("--> nfs_probe_fsinfo()\n");
780 
781 	if (clp->rpc_ops->set_capabilities != NULL) {
782 		error = clp->rpc_ops->set_capabilities(server, mntfh);
783 		if (error < 0)
784 			goto out_error;
785 	}
786 
787 	fsinfo.fattr = fattr;
788 	fsinfo.layouttype = 0;
789 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
790 	if (error < 0)
791 		goto out_error;
792 
793 	nfs_server_set_fsinfo(server, &fsinfo);
794 
795 	/* Get some general file system info */
796 	if (server->namelen == 0) {
797 		struct nfs_pathconf pathinfo;
798 
799 		pathinfo.fattr = fattr;
800 		nfs_fattr_init(fattr);
801 
802 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
803 			server->namelen = pathinfo.max_namelen;
804 	}
805 
806 	dprintk("<-- nfs_probe_fsinfo() = 0\n");
807 	return 0;
808 
809 out_error:
810 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
811 	return error;
812 }
813 EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
814 
815 /*
816  * Copy useful information when duplicating a server record
817  */
818 void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
819 {
820 	target->flags = source->flags;
821 	target->rsize = source->rsize;
822 	target->wsize = source->wsize;
823 	target->acregmin = source->acregmin;
824 	target->acregmax = source->acregmax;
825 	target->acdirmin = source->acdirmin;
826 	target->acdirmax = source->acdirmax;
827 	target->caps = source->caps;
828 	target->options = source->options;
829 	target->auth_info = source->auth_info;
830 }
831 EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
832 
833 void nfs_server_insert_lists(struct nfs_server *server)
834 {
835 	struct nfs_client *clp = server->nfs_client;
836 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
837 
838 	spin_lock(&nn->nfs_client_lock);
839 	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
840 	list_add_tail(&server->master_link, &nn->nfs_volume_list);
841 	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
842 	spin_unlock(&nn->nfs_client_lock);
843 
844 }
845 EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
846 
847 void nfs_server_remove_lists(struct nfs_server *server)
848 {
849 	struct nfs_client *clp = server->nfs_client;
850 	struct nfs_net *nn;
851 
852 	if (clp == NULL)
853 		return;
854 	nn = net_generic(clp->cl_net, nfs_net_id);
855 	spin_lock(&nn->nfs_client_lock);
856 	list_del_rcu(&server->client_link);
857 	if (list_empty(&clp->cl_superblocks))
858 		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
859 	list_del(&server->master_link);
860 	spin_unlock(&nn->nfs_client_lock);
861 
862 	synchronize_rcu();
863 }
864 EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
865 
866 /*
867  * Allocate and initialise a server record
868  */
869 struct nfs_server *nfs_alloc_server(void)
870 {
871 	struct nfs_server *server;
872 
873 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
874 	if (!server)
875 		return NULL;
876 
877 	server->client = server->client_acl = ERR_PTR(-EINVAL);
878 
879 	/* Zero out the NFS state stuff */
880 	INIT_LIST_HEAD(&server->client_link);
881 	INIT_LIST_HEAD(&server->master_link);
882 	INIT_LIST_HEAD(&server->delegations);
883 	INIT_LIST_HEAD(&server->layouts);
884 	INIT_LIST_HEAD(&server->state_owners_lru);
885 
886 	atomic_set(&server->active, 0);
887 
888 	server->io_stats = nfs_alloc_iostats();
889 	if (!server->io_stats) {
890 		kfree(server);
891 		return NULL;
892 	}
893 
894 	if (bdi_init(&server->backing_dev_info)) {
895 		nfs_free_iostats(server->io_stats);
896 		kfree(server);
897 		return NULL;
898 	}
899 
900 	ida_init(&server->openowner_id);
901 	ida_init(&server->lockowner_id);
902 	pnfs_init_server(server);
903 
904 	return server;
905 }
906 EXPORT_SYMBOL_GPL(nfs_alloc_server);
907 
908 /*
909  * Free up a server record
910  */
911 void nfs_free_server(struct nfs_server *server)
912 {
913 	dprintk("--> nfs_free_server()\n");
914 
915 	nfs_server_remove_lists(server);
916 
917 	if (server->destroy != NULL)
918 		server->destroy(server);
919 
920 	if (!IS_ERR(server->client_acl))
921 		rpc_shutdown_client(server->client_acl);
922 	if (!IS_ERR(server->client))
923 		rpc_shutdown_client(server->client);
924 
925 	nfs_put_client(server->nfs_client);
926 
927 	ida_destroy(&server->lockowner_id);
928 	ida_destroy(&server->openowner_id);
929 	nfs_free_iostats(server->io_stats);
930 	bdi_destroy(&server->backing_dev_info);
931 	kfree(server);
932 	nfs_release_automount_timer();
933 	dprintk("<-- nfs_free_server()\n");
934 }
935 EXPORT_SYMBOL_GPL(nfs_free_server);
936 
937 /*
938  * Create a version 2 or 3 volume record
939  * - keyed on server and FSID
940  */
941 struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
942 				     struct nfs_subversion *nfs_mod)
943 {
944 	struct nfs_server *server;
945 	struct nfs_fattr *fattr;
946 	int error;
947 
948 	server = nfs_alloc_server();
949 	if (!server)
950 		return ERR_PTR(-ENOMEM);
951 
952 	error = -ENOMEM;
953 	fattr = nfs_alloc_fattr();
954 	if (fattr == NULL)
955 		goto error;
956 
957 	/* Get a client representation */
958 	error = nfs_init_server(server, mount_info->parsed, nfs_mod);
959 	if (error < 0)
960 		goto error;
961 
962 	/* Probe the root fh to retrieve its FSID */
963 	error = nfs_probe_fsinfo(server, mount_info->mntfh, fattr);
964 	if (error < 0)
965 		goto error;
966 	if (server->nfs_client->rpc_ops->version == 3) {
967 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
968 			server->namelen = NFS3_MAXNAMLEN;
969 		if (!(mount_info->parsed->flags & NFS_MOUNT_NORDIRPLUS))
970 			server->caps |= NFS_CAP_READDIRPLUS;
971 	} else {
972 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
973 			server->namelen = NFS2_MAXNAMLEN;
974 	}
975 
976 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
977 		error = nfs_mod->rpc_ops->getattr(server, mount_info->mntfh, fattr, NULL);
978 		if (error < 0) {
979 			dprintk("nfs_create_server: getattr error = %d\n", -error);
980 			goto error;
981 		}
982 	}
983 	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
984 
985 	dprintk("Server FSID: %llx:%llx\n",
986 		(unsigned long long) server->fsid.major,
987 		(unsigned long long) server->fsid.minor);
988 
989 	nfs_server_insert_lists(server);
990 	server->mount_time = jiffies;
991 	nfs_free_fattr(fattr);
992 	return server;
993 
994 error:
995 	nfs_free_fattr(fattr);
996 	nfs_free_server(server);
997 	return ERR_PTR(error);
998 }
999 EXPORT_SYMBOL_GPL(nfs_create_server);
1000 
1001 /*
1002  * Clone an NFS2, NFS3 or NFS4 server record
1003  */
1004 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1005 				    struct nfs_fh *fh,
1006 				    struct nfs_fattr *fattr,
1007 				    rpc_authflavor_t flavor)
1008 {
1009 	struct nfs_server *server;
1010 	struct nfs_fattr *fattr_fsinfo;
1011 	int error;
1012 
1013 	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1014 		(unsigned long long) fattr->fsid.major,
1015 		(unsigned long long) fattr->fsid.minor);
1016 
1017 	server = nfs_alloc_server();
1018 	if (!server)
1019 		return ERR_PTR(-ENOMEM);
1020 
1021 	error = -ENOMEM;
1022 	fattr_fsinfo = nfs_alloc_fattr();
1023 	if (fattr_fsinfo == NULL)
1024 		goto out_free_server;
1025 
1026 	/* Copy data from the source */
1027 	server->nfs_client = source->nfs_client;
1028 	server->destroy = source->destroy;
1029 	atomic_inc(&server->nfs_client->cl_count);
1030 	nfs_server_copy_userdata(server, source);
1031 
1032 	server->fsid = fattr->fsid;
1033 
1034 	error = nfs_init_server_rpcclient(server,
1035 			source->client->cl_timeout,
1036 			flavor);
1037 	if (error < 0)
1038 		goto out_free_server;
1039 
1040 	/* probe the filesystem info for this server filesystem */
1041 	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1042 	if (error < 0)
1043 		goto out_free_server;
1044 
1045 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1046 		server->namelen = NFS4_MAXNAMLEN;
1047 
1048 	dprintk("Cloned FSID: %llx:%llx\n",
1049 		(unsigned long long) server->fsid.major,
1050 		(unsigned long long) server->fsid.minor);
1051 
1052 	error = nfs_start_lockd(server);
1053 	if (error < 0)
1054 		goto out_free_server;
1055 
1056 	nfs_server_insert_lists(server);
1057 	server->mount_time = jiffies;
1058 
1059 	nfs_free_fattr(fattr_fsinfo);
1060 	dprintk("<-- nfs_clone_server() = %p\n", server);
1061 	return server;
1062 
1063 out_free_server:
1064 	nfs_free_fattr(fattr_fsinfo);
1065 	nfs_free_server(server);
1066 	dprintk("<-- nfs_clone_server() = error %d\n", error);
1067 	return ERR_PTR(error);
1068 }
1069 EXPORT_SYMBOL_GPL(nfs_clone_server);
1070 
1071 void nfs_clients_init(struct net *net)
1072 {
1073 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1074 
1075 	INIT_LIST_HEAD(&nn->nfs_client_list);
1076 	INIT_LIST_HEAD(&nn->nfs_volume_list);
1077 #if IS_ENABLED(CONFIG_NFS_V4)
1078 	idr_init(&nn->cb_ident_idr);
1079 #endif
1080 	spin_lock_init(&nn->nfs_client_lock);
1081 	nn->boot_time = CURRENT_TIME;
1082 }
1083 
1084 #ifdef CONFIG_PROC_FS
1085 static int nfs_server_list_open(struct inode *inode, struct file *file);
1086 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1087 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1088 static void nfs_server_list_stop(struct seq_file *p, void *v);
1089 static int nfs_server_list_show(struct seq_file *m, void *v);
1090 
1091 static const struct seq_operations nfs_server_list_ops = {
1092 	.start	= nfs_server_list_start,
1093 	.next	= nfs_server_list_next,
1094 	.stop	= nfs_server_list_stop,
1095 	.show	= nfs_server_list_show,
1096 };
1097 
1098 static const struct file_operations nfs_server_list_fops = {
1099 	.open		= nfs_server_list_open,
1100 	.read		= seq_read,
1101 	.llseek		= seq_lseek,
1102 	.release	= seq_release_net,
1103 };
1104 
1105 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1106 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1107 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1108 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1109 static int nfs_volume_list_show(struct seq_file *m, void *v);
1110 
1111 static const struct seq_operations nfs_volume_list_ops = {
1112 	.start	= nfs_volume_list_start,
1113 	.next	= nfs_volume_list_next,
1114 	.stop	= nfs_volume_list_stop,
1115 	.show	= nfs_volume_list_show,
1116 };
1117 
1118 static const struct file_operations nfs_volume_list_fops = {
1119 	.open		= nfs_volume_list_open,
1120 	.read		= seq_read,
1121 	.llseek		= seq_lseek,
1122 	.release	= seq_release_net,
1123 };
1124 
1125 /*
1126  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1127  * we're dealing
1128  */
1129 static int nfs_server_list_open(struct inode *inode, struct file *file)
1130 {
1131 	return seq_open_net(inode, file, &nfs_server_list_ops,
1132 			   sizeof(struct seq_net_private));
1133 }
1134 
1135 /*
1136  * set up the iterator to start reading from the server list and return the first item
1137  */
1138 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1139 				__acquires(&nn->nfs_client_lock)
1140 {
1141 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1142 
1143 	/* lock the list against modification */
1144 	spin_lock(&nn->nfs_client_lock);
1145 	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1146 }
1147 
1148 /*
1149  * move to next server
1150  */
1151 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1152 {
1153 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1154 
1155 	return seq_list_next(v, &nn->nfs_client_list, pos);
1156 }
1157 
1158 /*
1159  * clean up after reading from the transports list
1160  */
1161 static void nfs_server_list_stop(struct seq_file *p, void *v)
1162 				__releases(&nn->nfs_client_lock)
1163 {
1164 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1165 
1166 	spin_unlock(&nn->nfs_client_lock);
1167 }
1168 
1169 /*
1170  * display a header line followed by a load of call lines
1171  */
1172 static int nfs_server_list_show(struct seq_file *m, void *v)
1173 {
1174 	struct nfs_client *clp;
1175 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1176 
1177 	/* display header on line 1 */
1178 	if (v == &nn->nfs_client_list) {
1179 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1180 		return 0;
1181 	}
1182 
1183 	/* display one transport per line on subsequent lines */
1184 	clp = list_entry(v, struct nfs_client, cl_share_link);
1185 
1186 	/* Check if the client is initialized */
1187 	if (clp->cl_cons_state != NFS_CS_READY)
1188 		return 0;
1189 
1190 	rcu_read_lock();
1191 	seq_printf(m, "v%u %s %s %3d %s\n",
1192 		   clp->rpc_ops->version,
1193 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1194 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1195 		   atomic_read(&clp->cl_count),
1196 		   clp->cl_hostname);
1197 	rcu_read_unlock();
1198 
1199 	return 0;
1200 }
1201 
1202 /*
1203  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1204  */
1205 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1206 {
1207 	return seq_open_net(inode, file, &nfs_volume_list_ops,
1208 			   sizeof(struct seq_net_private));
1209 }
1210 
1211 /*
1212  * set up the iterator to start reading from the volume list and return the first item
1213  */
1214 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1215 				__acquires(&nn->nfs_client_lock)
1216 {
1217 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1218 
1219 	/* lock the list against modification */
1220 	spin_lock(&nn->nfs_client_lock);
1221 	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1222 }
1223 
1224 /*
1225  * move to next volume
1226  */
1227 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1228 {
1229 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1230 
1231 	return seq_list_next(v, &nn->nfs_volume_list, pos);
1232 }
1233 
1234 /*
1235  * clean up after reading from the transports list
1236  */
1237 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1238 				__releases(&nn->nfs_client_lock)
1239 {
1240 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1241 
1242 	spin_unlock(&nn->nfs_client_lock);
1243 }
1244 
1245 /*
1246  * display a header line followed by a load of call lines
1247  */
1248 static int nfs_volume_list_show(struct seq_file *m, void *v)
1249 {
1250 	struct nfs_server *server;
1251 	struct nfs_client *clp;
1252 	char dev[13];	// 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1253 	char fsid[34];	// 2 * 16 for %llx, 1 for ':', 1 for '\0'
1254 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1255 
1256 	/* display header on line 1 */
1257 	if (v == &nn->nfs_volume_list) {
1258 		seq_puts(m, "NV SERVER   PORT DEV          FSID"
1259 			    "                              FSC\n");
1260 		return 0;
1261 	}
1262 	/* display one transport per line on subsequent lines */
1263 	server = list_entry(v, struct nfs_server, master_link);
1264 	clp = server->nfs_client;
1265 
1266 	snprintf(dev, sizeof(dev), "%u:%u",
1267 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1268 
1269 	snprintf(fsid, sizeof(fsid), "%llx:%llx",
1270 		 (unsigned long long) server->fsid.major,
1271 		 (unsigned long long) server->fsid.minor);
1272 
1273 	rcu_read_lock();
1274 	seq_printf(m, "v%u %s %s %-12s %-33s %s\n",
1275 		   clp->rpc_ops->version,
1276 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1277 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1278 		   dev,
1279 		   fsid,
1280 		   nfs_server_fscache_state(server));
1281 	rcu_read_unlock();
1282 
1283 	return 0;
1284 }
1285 
1286 int nfs_fs_proc_net_init(struct net *net)
1287 {
1288 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1289 	struct proc_dir_entry *p;
1290 
1291 	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1292 	if (!nn->proc_nfsfs)
1293 		goto error_0;
1294 
1295 	/* a file of servers with which we're dealing */
1296 	p = proc_create("servers", S_IFREG|S_IRUGO,
1297 			nn->proc_nfsfs, &nfs_server_list_fops);
1298 	if (!p)
1299 		goto error_1;
1300 
1301 	/* a file of volumes that we have mounted */
1302 	p = proc_create("volumes", S_IFREG|S_IRUGO,
1303 			nn->proc_nfsfs, &nfs_volume_list_fops);
1304 	if (!p)
1305 		goto error_1;
1306 	return 0;
1307 
1308 error_1:
1309 	remove_proc_subtree("nfsfs", net->proc_net);
1310 error_0:
1311 	return -ENOMEM;
1312 }
1313 
1314 void nfs_fs_proc_net_exit(struct net *net)
1315 {
1316 	remove_proc_subtree("nfsfs", net->proc_net);
1317 }
1318 
1319 /*
1320  * initialise the /proc/fs/nfsfs/ directory
1321  */
1322 int __init nfs_fs_proc_init(void)
1323 {
1324 	if (!proc_mkdir("fs/nfsfs", NULL))
1325 		goto error_0;
1326 
1327 	/* a file of servers with which we're dealing */
1328 	if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1329 		goto error_1;
1330 
1331 	/* a file of volumes that we have mounted */
1332 	if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1333 		goto error_1;
1334 
1335 	return 0;
1336 error_1:
1337 	remove_proc_subtree("fs/nfsfs", NULL);
1338 error_0:
1339 	return -ENOMEM;
1340 }
1341 
1342 /*
1343  * clean up the /proc/fs/nfsfs/ directory
1344  */
1345 void nfs_fs_proc_exit(void)
1346 {
1347 	remove_proc_subtree("fs/nfsfs", NULL);
1348 }
1349 
1350 #endif /* CONFIG_PROC_FS */
1351