xref: /openbmc/linux/fs/nfs/client.c (revision b96fc2f3)
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 	       const struct rpc_timeout *timeparms,
371 	       const char *ip_addr,
372 	       rpc_authflavor_t authflavour)
373 {
374 	struct nfs_client *clp, *new = NULL;
375 	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
376 	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
377 
378 	if (cl_init->hostname == NULL) {
379 		WARN_ON(1);
380 		return NULL;
381 	}
382 
383 	dprintk("--> nfs_get_client(%s,v%u)\n",
384 		cl_init->hostname, rpc_ops->version);
385 
386 	/* see if the client already exists */
387 	do {
388 		spin_lock(&nn->nfs_client_lock);
389 
390 		clp = nfs_match_client(cl_init);
391 		if (clp) {
392 			spin_unlock(&nn->nfs_client_lock);
393 			if (new)
394 				new->rpc_ops->free_client(new);
395 			return nfs_found_client(cl_init, clp);
396 		}
397 		if (new) {
398 			list_add_tail(&new->cl_share_link,
399 					&nn->nfs_client_list);
400 			spin_unlock(&nn->nfs_client_lock);
401 			new->cl_flags = cl_init->init_flags;
402 			return rpc_ops->init_client(new, timeparms, ip_addr);
403 		}
404 
405 		spin_unlock(&nn->nfs_client_lock);
406 
407 		new = rpc_ops->alloc_client(cl_init);
408 	} while (!IS_ERR(new));
409 
410 	dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
411 		cl_init->hostname, PTR_ERR(new));
412 	return new;
413 }
414 EXPORT_SYMBOL_GPL(nfs_get_client);
415 
416 /*
417  * Mark a server as ready or failed
418  */
419 void nfs_mark_client_ready(struct nfs_client *clp, int state)
420 {
421 	smp_wmb();
422 	clp->cl_cons_state = state;
423 	wake_up_all(&nfs_client_active_wq);
424 }
425 EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
426 
427 /*
428  * Initialise the timeout values for a connection
429  */
430 void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
431 				    unsigned int timeo, unsigned int retrans)
432 {
433 	to->to_initval = timeo * HZ / 10;
434 	to->to_retries = retrans;
435 
436 	switch (proto) {
437 	case XPRT_TRANSPORT_TCP:
438 	case XPRT_TRANSPORT_RDMA:
439 		if (to->to_retries == 0)
440 			to->to_retries = NFS_DEF_TCP_RETRANS;
441 		if (to->to_initval == 0)
442 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
443 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
444 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
445 		to->to_increment = to->to_initval;
446 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
447 		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
448 			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
449 		if (to->to_maxval < to->to_initval)
450 			to->to_maxval = to->to_initval;
451 		to->to_exponential = 0;
452 		break;
453 	case XPRT_TRANSPORT_UDP:
454 		if (to->to_retries == 0)
455 			to->to_retries = NFS_DEF_UDP_RETRANS;
456 		if (!to->to_initval)
457 			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
458 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
459 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
460 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
461 		to->to_exponential = 1;
462 		break;
463 	default:
464 		BUG();
465 	}
466 }
467 EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
468 
469 /*
470  * Create an RPC client handle
471  */
472 int nfs_create_rpc_client(struct nfs_client *clp,
473 			  const struct rpc_timeout *timeparms,
474 			  rpc_authflavor_t flavor)
475 {
476 	struct rpc_clnt		*clnt = NULL;
477 	struct rpc_create_args args = {
478 		.net		= clp->cl_net,
479 		.protocol	= clp->cl_proto,
480 		.address	= (struct sockaddr *)&clp->cl_addr,
481 		.addrsize	= clp->cl_addrlen,
482 		.timeout	= timeparms,
483 		.servername	= clp->cl_hostname,
484 		.program	= &nfs_program,
485 		.version	= clp->rpc_ops->version,
486 		.authflavor	= flavor,
487 	};
488 
489 	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
490 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
491 	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
492 		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
493 	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
494 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
495 	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
496 		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
497 
498 	if (!IS_ERR(clp->cl_rpcclient))
499 		return 0;
500 
501 	clnt = rpc_create(&args);
502 	if (IS_ERR(clnt)) {
503 		dprintk("%s: cannot create RPC client. Error = %ld\n",
504 				__func__, PTR_ERR(clnt));
505 		return PTR_ERR(clnt);
506 	}
507 
508 	clp->cl_rpcclient = clnt;
509 	return 0;
510 }
511 EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
512 
513 /*
514  * Version 2 or 3 client destruction
515  */
516 static void nfs_destroy_server(struct nfs_server *server)
517 {
518 	if (server->nlm_host)
519 		nlmclnt_done(server->nlm_host);
520 }
521 
522 /*
523  * Version 2 or 3 lockd setup
524  */
525 static int nfs_start_lockd(struct nfs_server *server)
526 {
527 	struct nlm_host *host;
528 	struct nfs_client *clp = server->nfs_client;
529 	struct nlmclnt_initdata nlm_init = {
530 		.hostname	= clp->cl_hostname,
531 		.address	= (struct sockaddr *)&clp->cl_addr,
532 		.addrlen	= clp->cl_addrlen,
533 		.nfs_version	= clp->rpc_ops->version,
534 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
535 					1 : 0,
536 		.net		= clp->cl_net,
537 	};
538 
539 	if (nlm_init.nfs_version > 3)
540 		return 0;
541 	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
542 			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
543 		return 0;
544 
545 	switch (clp->cl_proto) {
546 		default:
547 			nlm_init.protocol = IPPROTO_TCP;
548 			break;
549 		case XPRT_TRANSPORT_UDP:
550 			nlm_init.protocol = IPPROTO_UDP;
551 	}
552 
553 	host = nlmclnt_init(&nlm_init);
554 	if (IS_ERR(host))
555 		return PTR_ERR(host);
556 
557 	server->nlm_host = host;
558 	server->destroy = nfs_destroy_server;
559 	return 0;
560 }
561 
562 /*
563  * Create a general RPC client
564  */
565 int nfs_init_server_rpcclient(struct nfs_server *server,
566 		const struct rpc_timeout *timeo,
567 		rpc_authflavor_t pseudoflavour)
568 {
569 	struct nfs_client *clp = server->nfs_client;
570 
571 	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
572 							pseudoflavour);
573 	if (IS_ERR(server->client)) {
574 		dprintk("%s: couldn't create rpc_client!\n", __func__);
575 		return PTR_ERR(server->client);
576 	}
577 
578 	memcpy(&server->client->cl_timeout_default,
579 			timeo,
580 			sizeof(server->client->cl_timeout_default));
581 	server->client->cl_timeout = &server->client->cl_timeout_default;
582 	server->client->cl_softrtry = 0;
583 	if (server->flags & NFS_MOUNT_SOFT)
584 		server->client->cl_softrtry = 1;
585 
586 	return 0;
587 }
588 EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
589 
590 /**
591  * nfs_init_client - Initialise an NFS2 or NFS3 client
592  *
593  * @clp: nfs_client to initialise
594  * @timeparms: timeout parameters for underlying RPC transport
595  * @ip_addr: IP presentation address (not used)
596  *
597  * Returns pointer to an NFS client, or an ERR_PTR value.
598  */
599 struct nfs_client *nfs_init_client(struct nfs_client *clp,
600 		    const struct rpc_timeout *timeparms,
601 		    const char *ip_addr)
602 {
603 	int error;
604 
605 	if (clp->cl_cons_state == NFS_CS_READY) {
606 		/* the client is already initialised */
607 		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
608 		return clp;
609 	}
610 
611 	/*
612 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
613 	 * - RFC 2623, sec 2.3.2
614 	 */
615 	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
616 	if (error < 0)
617 		goto error;
618 	nfs_mark_client_ready(clp, NFS_CS_READY);
619 	return clp;
620 
621 error:
622 	nfs_mark_client_ready(clp, error);
623 	nfs_put_client(clp);
624 	dprintk("<-- nfs_init_client() = xerror %d\n", error);
625 	return ERR_PTR(error);
626 }
627 EXPORT_SYMBOL_GPL(nfs_init_client);
628 
629 /*
630  * Create a version 2 or 3 client
631  */
632 static int nfs_init_server(struct nfs_server *server,
633 			   const struct nfs_parsed_mount_data *data,
634 			   struct nfs_subversion *nfs_mod)
635 {
636 	struct nfs_client_initdata cl_init = {
637 		.hostname = data->nfs_server.hostname,
638 		.addr = (const struct sockaddr *)&data->nfs_server.address,
639 		.addrlen = data->nfs_server.addrlen,
640 		.nfs_mod = nfs_mod,
641 		.proto = data->nfs_server.protocol,
642 		.net = data->net,
643 	};
644 	struct rpc_timeout timeparms;
645 	struct nfs_client *clp;
646 	int error;
647 
648 	dprintk("--> nfs_init_server()\n");
649 
650 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
651 			data->timeo, data->retrans);
652 	if (data->flags & NFS_MOUNT_NORESVPORT)
653 		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
654 
655 	/* Allocate or find a client reference we can use */
656 	clp = nfs_get_client(&cl_init, &timeparms, NULL, RPC_AUTH_UNIX);
657 	if (IS_ERR(clp)) {
658 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
659 		return PTR_ERR(clp);
660 	}
661 
662 	server->nfs_client = clp;
663 
664 	/* Initialise the client representation from the mount data */
665 	server->flags = data->flags;
666 	server->options = data->options;
667 	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
668 		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
669 		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
670 
671 	if (data->rsize)
672 		server->rsize = nfs_block_size(data->rsize, NULL);
673 	if (data->wsize)
674 		server->wsize = nfs_block_size(data->wsize, NULL);
675 
676 	server->acregmin = data->acregmin * HZ;
677 	server->acregmax = data->acregmax * HZ;
678 	server->acdirmin = data->acdirmin * HZ;
679 	server->acdirmax = data->acdirmax * HZ;
680 
681 	/* Start lockd here, before we might error out */
682 	error = nfs_start_lockd(server);
683 	if (error < 0)
684 		goto error;
685 
686 	server->port = data->nfs_server.port;
687 	server->auth_info = data->auth_info;
688 
689 	error = nfs_init_server_rpcclient(server, &timeparms,
690 					  data->selected_flavor);
691 	if (error < 0)
692 		goto error;
693 
694 	/* Preserve the values of mount_server-related mount options */
695 	if (data->mount_server.addrlen) {
696 		memcpy(&server->mountd_address, &data->mount_server.address,
697 			data->mount_server.addrlen);
698 		server->mountd_addrlen = data->mount_server.addrlen;
699 	}
700 	server->mountd_version = data->mount_server.version;
701 	server->mountd_port = data->mount_server.port;
702 	server->mountd_protocol = data->mount_server.protocol;
703 
704 	server->namelen  = data->namlen;
705 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
706 	return 0;
707 
708 error:
709 	server->nfs_client = NULL;
710 	nfs_put_client(clp);
711 	dprintk("<-- nfs_init_server() = xerror %d\n", error);
712 	return error;
713 }
714 
715 /*
716  * Load up the server record from information gained in an fsinfo record
717  */
718 static void nfs_server_set_fsinfo(struct nfs_server *server,
719 				  struct nfs_fsinfo *fsinfo)
720 {
721 	unsigned long max_rpc_payload;
722 
723 	/* Work out a lot of parameters */
724 	if (server->rsize == 0)
725 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
726 	if (server->wsize == 0)
727 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
728 
729 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
730 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
731 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
732 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
733 
734 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
735 	if (server->rsize > max_rpc_payload)
736 		server->rsize = max_rpc_payload;
737 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
738 		server->rsize = NFS_MAX_FILE_IO_SIZE;
739 	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
740 
741 	server->backing_dev_info.name = "nfs";
742 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
743 
744 	if (server->wsize > max_rpc_payload)
745 		server->wsize = max_rpc_payload;
746 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
747 		server->wsize = NFS_MAX_FILE_IO_SIZE;
748 	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
749 
750 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
751 
752 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
753 	if (server->dtsize > PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES)
754 		server->dtsize = PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES;
755 	if (server->dtsize > server->rsize)
756 		server->dtsize = server->rsize;
757 
758 	if (server->flags & NFS_MOUNT_NOAC) {
759 		server->acregmin = server->acregmax = 0;
760 		server->acdirmin = server->acdirmax = 0;
761 	}
762 
763 	server->maxfilesize = fsinfo->maxfilesize;
764 
765 	server->time_delta = fsinfo->time_delta;
766 
767 	/* We're airborne Set socket buffersize */
768 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
769 }
770 
771 /*
772  * Probe filesystem information, including the FSID on v2/v3
773  */
774 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
775 {
776 	struct nfs_fsinfo fsinfo;
777 	struct nfs_client *clp = server->nfs_client;
778 	int error;
779 
780 	dprintk("--> nfs_probe_fsinfo()\n");
781 
782 	if (clp->rpc_ops->set_capabilities != NULL) {
783 		error = clp->rpc_ops->set_capabilities(server, mntfh);
784 		if (error < 0)
785 			goto out_error;
786 	}
787 
788 	fsinfo.fattr = fattr;
789 	fsinfo.layouttype = 0;
790 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
791 	if (error < 0)
792 		goto out_error;
793 
794 	nfs_server_set_fsinfo(server, &fsinfo);
795 
796 	/* Get some general file system info */
797 	if (server->namelen == 0) {
798 		struct nfs_pathconf pathinfo;
799 
800 		pathinfo.fattr = fattr;
801 		nfs_fattr_init(fattr);
802 
803 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
804 			server->namelen = pathinfo.max_namelen;
805 	}
806 
807 	dprintk("<-- nfs_probe_fsinfo() = 0\n");
808 	return 0;
809 
810 out_error:
811 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
812 	return error;
813 }
814 EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
815 
816 /*
817  * Copy useful information when duplicating a server record
818  */
819 void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
820 {
821 	target->flags = source->flags;
822 	target->rsize = source->rsize;
823 	target->wsize = source->wsize;
824 	target->acregmin = source->acregmin;
825 	target->acregmax = source->acregmax;
826 	target->acdirmin = source->acdirmin;
827 	target->acdirmax = source->acdirmax;
828 	target->caps = source->caps;
829 	target->options = source->options;
830 	target->auth_info = source->auth_info;
831 }
832 EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
833 
834 void nfs_server_insert_lists(struct nfs_server *server)
835 {
836 	struct nfs_client *clp = server->nfs_client;
837 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
838 
839 	spin_lock(&nn->nfs_client_lock);
840 	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
841 	list_add_tail(&server->master_link, &nn->nfs_volume_list);
842 	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
843 	spin_unlock(&nn->nfs_client_lock);
844 
845 }
846 EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
847 
848 void nfs_server_remove_lists(struct nfs_server *server)
849 {
850 	struct nfs_client *clp = server->nfs_client;
851 	struct nfs_net *nn;
852 
853 	if (clp == NULL)
854 		return;
855 	nn = net_generic(clp->cl_net, nfs_net_id);
856 	spin_lock(&nn->nfs_client_lock);
857 	list_del_rcu(&server->client_link);
858 	if (list_empty(&clp->cl_superblocks))
859 		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
860 	list_del(&server->master_link);
861 	spin_unlock(&nn->nfs_client_lock);
862 
863 	synchronize_rcu();
864 }
865 EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
866 
867 /*
868  * Allocate and initialise a server record
869  */
870 struct nfs_server *nfs_alloc_server(void)
871 {
872 	struct nfs_server *server;
873 
874 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
875 	if (!server)
876 		return NULL;
877 
878 	server->client = server->client_acl = ERR_PTR(-EINVAL);
879 
880 	/* Zero out the NFS state stuff */
881 	INIT_LIST_HEAD(&server->client_link);
882 	INIT_LIST_HEAD(&server->master_link);
883 	INIT_LIST_HEAD(&server->delegations);
884 	INIT_LIST_HEAD(&server->layouts);
885 	INIT_LIST_HEAD(&server->state_owners_lru);
886 
887 	atomic_set(&server->active, 0);
888 
889 	server->io_stats = nfs_alloc_iostats();
890 	if (!server->io_stats) {
891 		kfree(server);
892 		return NULL;
893 	}
894 
895 	if (bdi_init(&server->backing_dev_info)) {
896 		nfs_free_iostats(server->io_stats);
897 		kfree(server);
898 		return NULL;
899 	}
900 
901 	ida_init(&server->openowner_id);
902 	ida_init(&server->lockowner_id);
903 	pnfs_init_server(server);
904 
905 	return server;
906 }
907 EXPORT_SYMBOL_GPL(nfs_alloc_server);
908 
909 /*
910  * Free up a server record
911  */
912 void nfs_free_server(struct nfs_server *server)
913 {
914 	dprintk("--> nfs_free_server()\n");
915 
916 	nfs_server_remove_lists(server);
917 
918 	if (server->destroy != NULL)
919 		server->destroy(server);
920 
921 	if (!IS_ERR(server->client_acl))
922 		rpc_shutdown_client(server->client_acl);
923 	if (!IS_ERR(server->client))
924 		rpc_shutdown_client(server->client);
925 
926 	nfs_put_client(server->nfs_client);
927 
928 	ida_destroy(&server->lockowner_id);
929 	ida_destroy(&server->openowner_id);
930 	nfs_free_iostats(server->io_stats);
931 	bdi_destroy(&server->backing_dev_info);
932 	kfree(server);
933 	nfs_release_automount_timer();
934 	dprintk("<-- nfs_free_server()\n");
935 }
936 EXPORT_SYMBOL_GPL(nfs_free_server);
937 
938 /*
939  * Create a version 2 or 3 volume record
940  * - keyed on server and FSID
941  */
942 struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
943 				     struct nfs_subversion *nfs_mod)
944 {
945 	struct nfs_server *server;
946 	struct nfs_fattr *fattr;
947 	int error;
948 
949 	server = nfs_alloc_server();
950 	if (!server)
951 		return ERR_PTR(-ENOMEM);
952 
953 	error = -ENOMEM;
954 	fattr = nfs_alloc_fattr();
955 	if (fattr == NULL)
956 		goto error;
957 
958 	/* Get a client representation */
959 	error = nfs_init_server(server, mount_info->parsed, nfs_mod);
960 	if (error < 0)
961 		goto error;
962 
963 	/* Probe the root fh to retrieve its FSID */
964 	error = nfs_probe_fsinfo(server, mount_info->mntfh, fattr);
965 	if (error < 0)
966 		goto error;
967 	if (server->nfs_client->rpc_ops->version == 3) {
968 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
969 			server->namelen = NFS3_MAXNAMLEN;
970 		if (!(mount_info->parsed->flags & NFS_MOUNT_NORDIRPLUS))
971 			server->caps |= NFS_CAP_READDIRPLUS;
972 	} else {
973 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
974 			server->namelen = NFS2_MAXNAMLEN;
975 	}
976 
977 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
978 		error = nfs_mod->rpc_ops->getattr(server, mount_info->mntfh, fattr, NULL);
979 		if (error < 0) {
980 			dprintk("nfs_create_server: getattr error = %d\n", -error);
981 			goto error;
982 		}
983 	}
984 	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
985 
986 	dprintk("Server FSID: %llx:%llx\n",
987 		(unsigned long long) server->fsid.major,
988 		(unsigned long long) server->fsid.minor);
989 
990 	nfs_server_insert_lists(server);
991 	server->mount_time = jiffies;
992 	nfs_free_fattr(fattr);
993 	return server;
994 
995 error:
996 	nfs_free_fattr(fattr);
997 	nfs_free_server(server);
998 	return ERR_PTR(error);
999 }
1000 EXPORT_SYMBOL_GPL(nfs_create_server);
1001 
1002 /*
1003  * Clone an NFS2, NFS3 or NFS4 server record
1004  */
1005 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1006 				    struct nfs_fh *fh,
1007 				    struct nfs_fattr *fattr,
1008 				    rpc_authflavor_t flavor)
1009 {
1010 	struct nfs_server *server;
1011 	struct nfs_fattr *fattr_fsinfo;
1012 	int error;
1013 
1014 	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1015 		(unsigned long long) fattr->fsid.major,
1016 		(unsigned long long) fattr->fsid.minor);
1017 
1018 	server = nfs_alloc_server();
1019 	if (!server)
1020 		return ERR_PTR(-ENOMEM);
1021 
1022 	error = -ENOMEM;
1023 	fattr_fsinfo = nfs_alloc_fattr();
1024 	if (fattr_fsinfo == NULL)
1025 		goto out_free_server;
1026 
1027 	/* Copy data from the source */
1028 	server->nfs_client = source->nfs_client;
1029 	server->destroy = source->destroy;
1030 	atomic_inc(&server->nfs_client->cl_count);
1031 	nfs_server_copy_userdata(server, source);
1032 
1033 	server->fsid = fattr->fsid;
1034 
1035 	error = nfs_init_server_rpcclient(server,
1036 			source->client->cl_timeout,
1037 			flavor);
1038 	if (error < 0)
1039 		goto out_free_server;
1040 
1041 	/* probe the filesystem info for this server filesystem */
1042 	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1043 	if (error < 0)
1044 		goto out_free_server;
1045 
1046 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1047 		server->namelen = NFS4_MAXNAMLEN;
1048 
1049 	dprintk("Cloned FSID: %llx:%llx\n",
1050 		(unsigned long long) server->fsid.major,
1051 		(unsigned long long) server->fsid.minor);
1052 
1053 	error = nfs_start_lockd(server);
1054 	if (error < 0)
1055 		goto out_free_server;
1056 
1057 	nfs_server_insert_lists(server);
1058 	server->mount_time = jiffies;
1059 
1060 	nfs_free_fattr(fattr_fsinfo);
1061 	dprintk("<-- nfs_clone_server() = %p\n", server);
1062 	return server;
1063 
1064 out_free_server:
1065 	nfs_free_fattr(fattr_fsinfo);
1066 	nfs_free_server(server);
1067 	dprintk("<-- nfs_clone_server() = error %d\n", error);
1068 	return ERR_PTR(error);
1069 }
1070 EXPORT_SYMBOL_GPL(nfs_clone_server);
1071 
1072 void nfs_clients_init(struct net *net)
1073 {
1074 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1075 
1076 	INIT_LIST_HEAD(&nn->nfs_client_list);
1077 	INIT_LIST_HEAD(&nn->nfs_volume_list);
1078 #if IS_ENABLED(CONFIG_NFS_V4)
1079 	idr_init(&nn->cb_ident_idr);
1080 #endif
1081 	spin_lock_init(&nn->nfs_client_lock);
1082 	nn->boot_time = CURRENT_TIME;
1083 }
1084 
1085 #ifdef CONFIG_PROC_FS
1086 static int nfs_server_list_open(struct inode *inode, struct file *file);
1087 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1088 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1089 static void nfs_server_list_stop(struct seq_file *p, void *v);
1090 static int nfs_server_list_show(struct seq_file *m, void *v);
1091 
1092 static const struct seq_operations nfs_server_list_ops = {
1093 	.start	= nfs_server_list_start,
1094 	.next	= nfs_server_list_next,
1095 	.stop	= nfs_server_list_stop,
1096 	.show	= nfs_server_list_show,
1097 };
1098 
1099 static const struct file_operations nfs_server_list_fops = {
1100 	.open		= nfs_server_list_open,
1101 	.read		= seq_read,
1102 	.llseek		= seq_lseek,
1103 	.release	= seq_release_net,
1104 	.owner		= THIS_MODULE,
1105 };
1106 
1107 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1108 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1109 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1110 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1111 static int nfs_volume_list_show(struct seq_file *m, void *v);
1112 
1113 static const struct seq_operations nfs_volume_list_ops = {
1114 	.start	= nfs_volume_list_start,
1115 	.next	= nfs_volume_list_next,
1116 	.stop	= nfs_volume_list_stop,
1117 	.show	= nfs_volume_list_show,
1118 };
1119 
1120 static const struct file_operations nfs_volume_list_fops = {
1121 	.open		= nfs_volume_list_open,
1122 	.read		= seq_read,
1123 	.llseek		= seq_lseek,
1124 	.release	= seq_release_net,
1125 	.owner		= THIS_MODULE,
1126 };
1127 
1128 /*
1129  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1130  * we're dealing
1131  */
1132 static int nfs_server_list_open(struct inode *inode, struct file *file)
1133 {
1134 	return seq_open_net(inode, file, &nfs_server_list_ops,
1135 			   sizeof(struct seq_net_private));
1136 }
1137 
1138 /*
1139  * set up the iterator to start reading from the server list and return the first item
1140  */
1141 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1142 				__acquires(&nn->nfs_client_lock)
1143 {
1144 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1145 
1146 	/* lock the list against modification */
1147 	spin_lock(&nn->nfs_client_lock);
1148 	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1149 }
1150 
1151 /*
1152  * move to next server
1153  */
1154 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1155 {
1156 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1157 
1158 	return seq_list_next(v, &nn->nfs_client_list, pos);
1159 }
1160 
1161 /*
1162  * clean up after reading from the transports list
1163  */
1164 static void nfs_server_list_stop(struct seq_file *p, void *v)
1165 				__releases(&nn->nfs_client_lock)
1166 {
1167 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1168 
1169 	spin_unlock(&nn->nfs_client_lock);
1170 }
1171 
1172 /*
1173  * display a header line followed by a load of call lines
1174  */
1175 static int nfs_server_list_show(struct seq_file *m, void *v)
1176 {
1177 	struct nfs_client *clp;
1178 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1179 
1180 	/* display header on line 1 */
1181 	if (v == &nn->nfs_client_list) {
1182 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1183 		return 0;
1184 	}
1185 
1186 	/* display one transport per line on subsequent lines */
1187 	clp = list_entry(v, struct nfs_client, cl_share_link);
1188 
1189 	/* Check if the client is initialized */
1190 	if (clp->cl_cons_state != NFS_CS_READY)
1191 		return 0;
1192 
1193 	rcu_read_lock();
1194 	seq_printf(m, "v%u %s %s %3d %s\n",
1195 		   clp->rpc_ops->version,
1196 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1197 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1198 		   atomic_read(&clp->cl_count),
1199 		   clp->cl_hostname);
1200 	rcu_read_unlock();
1201 
1202 	return 0;
1203 }
1204 
1205 /*
1206  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1207  */
1208 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1209 {
1210 	return seq_open_net(inode, file, &nfs_volume_list_ops,
1211 			   sizeof(struct seq_net_private));
1212 }
1213 
1214 /*
1215  * set up the iterator to start reading from the volume list and return the first item
1216  */
1217 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1218 				__acquires(&nn->nfs_client_lock)
1219 {
1220 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1221 
1222 	/* lock the list against modification */
1223 	spin_lock(&nn->nfs_client_lock);
1224 	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1225 }
1226 
1227 /*
1228  * move to next volume
1229  */
1230 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1231 {
1232 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1233 
1234 	return seq_list_next(v, &nn->nfs_volume_list, pos);
1235 }
1236 
1237 /*
1238  * clean up after reading from the transports list
1239  */
1240 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1241 				__releases(&nn->nfs_client_lock)
1242 {
1243 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1244 
1245 	spin_unlock(&nn->nfs_client_lock);
1246 }
1247 
1248 /*
1249  * display a header line followed by a load of call lines
1250  */
1251 static int nfs_volume_list_show(struct seq_file *m, void *v)
1252 {
1253 	struct nfs_server *server;
1254 	struct nfs_client *clp;
1255 	char dev[13];	// 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1256 	char fsid[34];	// 2 * 16 for %llx, 1 for ':', 1 for '\0'
1257 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1258 
1259 	/* display header on line 1 */
1260 	if (v == &nn->nfs_volume_list) {
1261 		seq_puts(m, "NV SERVER   PORT DEV          FSID"
1262 			    "                              FSC\n");
1263 		return 0;
1264 	}
1265 	/* display one transport per line on subsequent lines */
1266 	server = list_entry(v, struct nfs_server, master_link);
1267 	clp = server->nfs_client;
1268 
1269 	snprintf(dev, sizeof(dev), "%u:%u",
1270 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1271 
1272 	snprintf(fsid, sizeof(fsid), "%llx:%llx",
1273 		 (unsigned long long) server->fsid.major,
1274 		 (unsigned long long) server->fsid.minor);
1275 
1276 	rcu_read_lock();
1277 	seq_printf(m, "v%u %s %s %-12s %-33s %s\n",
1278 		   clp->rpc_ops->version,
1279 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1280 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1281 		   dev,
1282 		   fsid,
1283 		   nfs_server_fscache_state(server));
1284 	rcu_read_unlock();
1285 
1286 	return 0;
1287 }
1288 
1289 int nfs_fs_proc_net_init(struct net *net)
1290 {
1291 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1292 	struct proc_dir_entry *p;
1293 
1294 	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1295 	if (!nn->proc_nfsfs)
1296 		goto error_0;
1297 
1298 	/* a file of servers with which we're dealing */
1299 	p = proc_create("servers", S_IFREG|S_IRUGO,
1300 			nn->proc_nfsfs, &nfs_server_list_fops);
1301 	if (!p)
1302 		goto error_1;
1303 
1304 	/* a file of volumes that we have mounted */
1305 	p = proc_create("volumes", S_IFREG|S_IRUGO,
1306 			nn->proc_nfsfs, &nfs_volume_list_fops);
1307 	if (!p)
1308 		goto error_1;
1309 	return 0;
1310 
1311 error_1:
1312 	remove_proc_subtree("nfsfs", net->proc_net);
1313 error_0:
1314 	return -ENOMEM;
1315 }
1316 
1317 void nfs_fs_proc_net_exit(struct net *net)
1318 {
1319 	remove_proc_subtree("nfsfs", net->proc_net);
1320 }
1321 
1322 /*
1323  * initialise the /proc/fs/nfsfs/ directory
1324  */
1325 int __init nfs_fs_proc_init(void)
1326 {
1327 	if (!proc_mkdir("fs/nfsfs", NULL))
1328 		goto error_0;
1329 
1330 	/* a file of servers with which we're dealing */
1331 	if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1332 		goto error_1;
1333 
1334 	/* a file of volumes that we have mounted */
1335 	if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1336 		goto error_1;
1337 
1338 	return 0;
1339 error_1:
1340 	remove_proc_subtree("fs/nfsfs", NULL);
1341 error_0:
1342 	return -ENOMEM;
1343 }
1344 
1345 /*
1346  * clean up the /proc/fs/nfsfs/ directory
1347  */
1348 void nfs_fs_proc_exit(void)
1349 {
1350 	remove_proc_subtree("fs/nfsfs", NULL);
1351 }
1352 
1353 #endif /* CONFIG_PROC_FS */
1354