xref: /openbmc/linux/fs/nfs/client.c (revision 08720988)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* client.c: NFS client sharing and management code
3  *
4  * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 
8 
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/sched.h>
12 #include <linux/time.h>
13 #include <linux/kernel.h>
14 #include <linux/mm.h>
15 #include <linux/string.h>
16 #include <linux/stat.h>
17 #include <linux/errno.h>
18 #include <linux/unistd.h>
19 #include <linux/sunrpc/addr.h>
20 #include <linux/sunrpc/clnt.h>
21 #include <linux/sunrpc/stats.h>
22 #include <linux/sunrpc/metrics.h>
23 #include <linux/sunrpc/xprtsock.h>
24 #include <linux/sunrpc/xprtrdma.h>
25 #include <linux/nfs_fs.h>
26 #include <linux/nfs_mount.h>
27 #include <linux/nfs4_mount.h>
28 #include <linux/lockd/bind.h>
29 #include <linux/seq_file.h>
30 #include <linux/mount.h>
31 #include <linux/vfs.h>
32 #include <linux/inet.h>
33 #include <linux/in6.h>
34 #include <linux/slab.h>
35 #include <linux/idr.h>
36 #include <net/ipv6.h>
37 #include <linux/nfs_xdr.h>
38 #include <linux/sunrpc/bc_xprt.h>
39 #include <linux/nsproxy.h>
40 #include <linux/pid_namespace.h>
41 
42 
43 #include "nfs4_fs.h"
44 #include "callback.h"
45 #include "delegation.h"
46 #include "iostat.h"
47 #include "internal.h"
48 #include "fscache.h"
49 #include "pnfs.h"
50 #include "nfs.h"
51 #include "netns.h"
52 #include "sysfs.h"
53 
54 #define NFSDBG_FACILITY		NFSDBG_CLIENT
55 
56 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
57 static DEFINE_SPINLOCK(nfs_version_lock);
58 static DEFINE_MUTEX(nfs_version_mutex);
59 static LIST_HEAD(nfs_versions);
60 
61 /*
62  * RPC cruft for NFS
63  */
64 static const struct rpc_version *nfs_version[5] = {
65 	[2] = NULL,
66 	[3] = NULL,
67 	[4] = NULL,
68 };
69 
70 const struct rpc_program nfs_program = {
71 	.name			= "nfs",
72 	.number			= NFS_PROGRAM,
73 	.nrvers			= ARRAY_SIZE(nfs_version),
74 	.version		= nfs_version,
75 	.stats			= &nfs_rpcstat,
76 	.pipe_dir_name		= NFS_PIPE_DIRNAME,
77 };
78 
79 struct rpc_stat nfs_rpcstat = {
80 	.program		= &nfs_program
81 };
82 
83 static struct nfs_subversion *find_nfs_version(unsigned int version)
84 {
85 	struct nfs_subversion *nfs;
86 	spin_lock(&nfs_version_lock);
87 
88 	list_for_each_entry(nfs, &nfs_versions, list) {
89 		if (nfs->rpc_ops->version == version) {
90 			spin_unlock(&nfs_version_lock);
91 			return nfs;
92 		}
93 	}
94 
95 	spin_unlock(&nfs_version_lock);
96 	return ERR_PTR(-EPROTONOSUPPORT);
97 }
98 
99 struct nfs_subversion *get_nfs_version(unsigned int version)
100 {
101 	struct nfs_subversion *nfs = find_nfs_version(version);
102 
103 	if (IS_ERR(nfs)) {
104 		mutex_lock(&nfs_version_mutex);
105 		request_module("nfsv%d", version);
106 		nfs = find_nfs_version(version);
107 		mutex_unlock(&nfs_version_mutex);
108 	}
109 
110 	if (!IS_ERR(nfs) && !try_module_get(nfs->owner))
111 		return ERR_PTR(-EAGAIN);
112 	return nfs;
113 }
114 
115 void put_nfs_version(struct nfs_subversion *nfs)
116 {
117 	module_put(nfs->owner);
118 }
119 
120 void register_nfs_version(struct nfs_subversion *nfs)
121 {
122 	spin_lock(&nfs_version_lock);
123 
124 	list_add(&nfs->list, &nfs_versions);
125 	nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
126 
127 	spin_unlock(&nfs_version_lock);
128 }
129 EXPORT_SYMBOL_GPL(register_nfs_version);
130 
131 void unregister_nfs_version(struct nfs_subversion *nfs)
132 {
133 	spin_lock(&nfs_version_lock);
134 
135 	nfs_version[nfs->rpc_ops->version] = NULL;
136 	list_del(&nfs->list);
137 
138 	spin_unlock(&nfs_version_lock);
139 }
140 EXPORT_SYMBOL_GPL(unregister_nfs_version);
141 
142 /*
143  * Allocate a shared client record
144  *
145  * Since these are allocated/deallocated very rarely, we don't
146  * bother putting them in a slab cache...
147  */
148 struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
149 {
150 	struct nfs_client *clp;
151 	int err = -ENOMEM;
152 
153 	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
154 		goto error_0;
155 
156 	clp->cl_nfs_mod = cl_init->nfs_mod;
157 	if (!try_module_get(clp->cl_nfs_mod->owner))
158 		goto error_dealloc;
159 
160 	clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
161 
162 	refcount_set(&clp->cl_count, 1);
163 	clp->cl_cons_state = NFS_CS_INITING;
164 
165 	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
166 	clp->cl_addrlen = cl_init->addrlen;
167 
168 	if (cl_init->hostname) {
169 		err = -ENOMEM;
170 		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
171 		if (!clp->cl_hostname)
172 			goto error_cleanup;
173 	}
174 
175 	INIT_LIST_HEAD(&clp->cl_superblocks);
176 	clp->cl_rpcclient = ERR_PTR(-EINVAL);
177 
178 	clp->cl_proto = cl_init->proto;
179 	clp->cl_nconnect = cl_init->nconnect;
180 	clp->cl_net = get_net(cl_init->net);
181 
182 	clp->cl_principal = "*";
183 	nfs_fscache_get_client_cookie(clp);
184 
185 	return clp;
186 
187 error_cleanup:
188 	put_nfs_version(clp->cl_nfs_mod);
189 error_dealloc:
190 	kfree(clp);
191 error_0:
192 	return ERR_PTR(err);
193 }
194 EXPORT_SYMBOL_GPL(nfs_alloc_client);
195 
196 #if IS_ENABLED(CONFIG_NFS_V4)
197 static void nfs_cleanup_cb_ident_idr(struct net *net)
198 {
199 	struct nfs_net *nn = net_generic(net, nfs_net_id);
200 
201 	idr_destroy(&nn->cb_ident_idr);
202 }
203 
204 /* nfs_client_lock held */
205 static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
206 {
207 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
208 
209 	if (clp->cl_cb_ident)
210 		idr_remove(&nn->cb_ident_idr, clp->cl_cb_ident);
211 }
212 
213 static void pnfs_init_server(struct nfs_server *server)
214 {
215 	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
216 }
217 
218 #else
219 static void nfs_cleanup_cb_ident_idr(struct net *net)
220 {
221 }
222 
223 static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
224 {
225 }
226 
227 static void pnfs_init_server(struct nfs_server *server)
228 {
229 }
230 
231 #endif /* CONFIG_NFS_V4 */
232 
233 /*
234  * Destroy a shared client record
235  */
236 void nfs_free_client(struct nfs_client *clp)
237 {
238 	nfs_fscache_release_client_cookie(clp);
239 
240 	/* -EIO all pending I/O */
241 	if (!IS_ERR(clp->cl_rpcclient))
242 		rpc_shutdown_client(clp->cl_rpcclient);
243 
244 	put_net(clp->cl_net);
245 	put_nfs_version(clp->cl_nfs_mod);
246 	kfree(clp->cl_hostname);
247 	kfree(clp->cl_acceptor);
248 	kfree(clp);
249 }
250 EXPORT_SYMBOL_GPL(nfs_free_client);
251 
252 /*
253  * Release a reference to a shared client record
254  */
255 void nfs_put_client(struct nfs_client *clp)
256 {
257 	struct nfs_net *nn;
258 
259 	if (!clp)
260 		return;
261 
262 	nn = net_generic(clp->cl_net, nfs_net_id);
263 
264 	if (refcount_dec_and_lock(&clp->cl_count, &nn->nfs_client_lock)) {
265 		list_del(&clp->cl_share_link);
266 		nfs_cb_idr_remove_locked(clp);
267 		spin_unlock(&nn->nfs_client_lock);
268 
269 		WARN_ON_ONCE(!list_empty(&clp->cl_superblocks));
270 
271 		clp->rpc_ops->free_client(clp);
272 	}
273 }
274 EXPORT_SYMBOL_GPL(nfs_put_client);
275 
276 /*
277  * Find an nfs_client on the list that matches the initialisation data
278  * that is supplied.
279  */
280 static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
281 {
282 	struct nfs_client *clp;
283 	const struct sockaddr *sap = data->addr;
284 	struct nfs_net *nn = net_generic(data->net, nfs_net_id);
285 	int error;
286 
287 again:
288 	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
289 	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
290 		/* Don't match clients that failed to initialise properly */
291 		if (clp->cl_cons_state < 0)
292 			continue;
293 
294 		/* If a client is still initializing then we need to wait */
295 		if (clp->cl_cons_state > NFS_CS_READY) {
296 			refcount_inc(&clp->cl_count);
297 			spin_unlock(&nn->nfs_client_lock);
298 			error = nfs_wait_client_init_complete(clp);
299 			nfs_put_client(clp);
300 			spin_lock(&nn->nfs_client_lock);
301 			if (error < 0)
302 				return ERR_PTR(error);
303 			goto again;
304 		}
305 
306 		/* Different NFS versions cannot share the same nfs_client */
307 		if (clp->rpc_ops != data->nfs_mod->rpc_ops)
308 			continue;
309 
310 		if (clp->cl_proto != data->proto)
311 			continue;
312 		/* Match nfsv4 minorversion */
313 		if (clp->cl_minorversion != data->minorversion)
314 			continue;
315 
316 		/* Match request for a dedicated DS */
317 		if (test_bit(NFS_CS_DS, &data->init_flags) !=
318 		    test_bit(NFS_CS_DS, &clp->cl_flags))
319 			continue;
320 
321 		/* Match the full socket address */
322 		if (!rpc_cmp_addr_port(sap, clap))
323 			/* Match all xprt_switch full socket addresses */
324 			if (IS_ERR(clp->cl_rpcclient) ||
325                             !rpc_clnt_xprt_switch_has_addr(clp->cl_rpcclient,
326 							   sap))
327 				continue;
328 
329 		refcount_inc(&clp->cl_count);
330 		return clp;
331 	}
332 	return NULL;
333 }
334 
335 /*
336  * Return true if @clp is done initializing, false if still working on it.
337  *
338  * Use nfs_client_init_status to check if it was successful.
339  */
340 bool nfs_client_init_is_complete(const struct nfs_client *clp)
341 {
342 	return clp->cl_cons_state <= NFS_CS_READY;
343 }
344 EXPORT_SYMBOL_GPL(nfs_client_init_is_complete);
345 
346 /*
347  * Return 0 if @clp was successfully initialized, -errno otherwise.
348  *
349  * This must be called *after* nfs_client_init_is_complete() returns true,
350  * otherwise it will pop WARN_ON_ONCE and return -EINVAL
351  */
352 int nfs_client_init_status(const struct nfs_client *clp)
353 {
354 	/* called without checking nfs_client_init_is_complete */
355 	if (clp->cl_cons_state > NFS_CS_READY) {
356 		WARN_ON_ONCE(1);
357 		return -EINVAL;
358 	}
359 	return clp->cl_cons_state;
360 }
361 EXPORT_SYMBOL_GPL(nfs_client_init_status);
362 
363 int nfs_wait_client_init_complete(const struct nfs_client *clp)
364 {
365 	return wait_event_killable(nfs_client_active_wq,
366 			nfs_client_init_is_complete(clp));
367 }
368 EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
369 
370 /*
371  * Found an existing client.  Make sure it's ready before returning.
372  */
373 static struct nfs_client *
374 nfs_found_client(const struct nfs_client_initdata *cl_init,
375 		 struct nfs_client *clp)
376 {
377 	int error;
378 
379 	error = nfs_wait_client_init_complete(clp);
380 	if (error < 0) {
381 		nfs_put_client(clp);
382 		return ERR_PTR(-ERESTARTSYS);
383 	}
384 
385 	if (clp->cl_cons_state < NFS_CS_READY) {
386 		error = clp->cl_cons_state;
387 		nfs_put_client(clp);
388 		return ERR_PTR(error);
389 	}
390 
391 	smp_rmb();
392 	return clp;
393 }
394 
395 /*
396  * Look up a client by IP address and protocol version
397  * - creates a new record if one doesn't yet exist
398  */
399 struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
400 {
401 	struct nfs_client *clp, *new = NULL;
402 	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
403 	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
404 
405 	if (cl_init->hostname == NULL) {
406 		WARN_ON(1);
407 		return NULL;
408 	}
409 
410 	/* see if the client already exists */
411 	do {
412 		spin_lock(&nn->nfs_client_lock);
413 
414 		clp = nfs_match_client(cl_init);
415 		if (clp) {
416 			spin_unlock(&nn->nfs_client_lock);
417 			if (new)
418 				new->rpc_ops->free_client(new);
419 			if (IS_ERR(clp))
420 				return clp;
421 			return nfs_found_client(cl_init, clp);
422 		}
423 		if (new) {
424 			list_add_tail(&new->cl_share_link,
425 					&nn->nfs_client_list);
426 			spin_unlock(&nn->nfs_client_lock);
427 			new->cl_flags = cl_init->init_flags;
428 			return rpc_ops->init_client(new, cl_init);
429 		}
430 
431 		spin_unlock(&nn->nfs_client_lock);
432 
433 		new = rpc_ops->alloc_client(cl_init);
434 	} while (!IS_ERR(new));
435 
436 	return new;
437 }
438 EXPORT_SYMBOL_GPL(nfs_get_client);
439 
440 /*
441  * Mark a server as ready or failed
442  */
443 void nfs_mark_client_ready(struct nfs_client *clp, int state)
444 {
445 	smp_wmb();
446 	clp->cl_cons_state = state;
447 	wake_up_all(&nfs_client_active_wq);
448 }
449 EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
450 
451 /*
452  * Initialise the timeout values for a connection
453  */
454 void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
455 				    int timeo, int retrans)
456 {
457 	to->to_initval = timeo * HZ / 10;
458 	to->to_retries = retrans;
459 
460 	switch (proto) {
461 	case XPRT_TRANSPORT_TCP:
462 	case XPRT_TRANSPORT_RDMA:
463 		if (retrans == NFS_UNSPEC_RETRANS)
464 			to->to_retries = NFS_DEF_TCP_RETRANS;
465 		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
466 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
467 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
468 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
469 		to->to_increment = to->to_initval;
470 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
471 		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
472 			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
473 		if (to->to_maxval < to->to_initval)
474 			to->to_maxval = to->to_initval;
475 		to->to_exponential = 0;
476 		break;
477 #ifndef CONFIG_NFS_DISABLE_UDP_SUPPORT
478 	case XPRT_TRANSPORT_UDP:
479 		if (retrans == NFS_UNSPEC_RETRANS)
480 			to->to_retries = NFS_DEF_UDP_RETRANS;
481 		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
482 			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
483 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
484 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
485 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
486 		to->to_exponential = 1;
487 		break;
488 #endif
489 	default:
490 		BUG();
491 	}
492 }
493 EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
494 
495 /*
496  * Create an RPC client handle
497  */
498 int nfs_create_rpc_client(struct nfs_client *clp,
499 			  const struct nfs_client_initdata *cl_init,
500 			  rpc_authflavor_t flavor)
501 {
502 	struct rpc_clnt		*clnt = NULL;
503 	struct rpc_create_args args = {
504 		.net		= clp->cl_net,
505 		.protocol	= clp->cl_proto,
506 		.nconnect	= clp->cl_nconnect,
507 		.address	= (struct sockaddr *)&clp->cl_addr,
508 		.addrsize	= clp->cl_addrlen,
509 		.timeout	= cl_init->timeparms,
510 		.servername	= clp->cl_hostname,
511 		.nodename	= cl_init->nodename,
512 		.program	= &nfs_program,
513 		.version	= clp->rpc_ops->version,
514 		.authflavor	= flavor,
515 		.cred		= cl_init->cred,
516 	};
517 
518 	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
519 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
520 	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
521 		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
522 	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
523 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
524 	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
525 		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
526 	if (test_bit(NFS_CS_NOPING, &clp->cl_flags))
527 		args.flags |= RPC_CLNT_CREATE_NOPING;
528 	if (test_bit(NFS_CS_REUSEPORT, &clp->cl_flags))
529 		args.flags |= RPC_CLNT_CREATE_REUSEPORT;
530 
531 	if (!IS_ERR(clp->cl_rpcclient))
532 		return 0;
533 
534 	clnt = rpc_create(&args);
535 	if (IS_ERR(clnt)) {
536 		dprintk("%s: cannot create RPC client. Error = %ld\n",
537 				__func__, PTR_ERR(clnt));
538 		return PTR_ERR(clnt);
539 	}
540 
541 	clnt->cl_principal = clp->cl_principal;
542 	clp->cl_rpcclient = clnt;
543 	return 0;
544 }
545 EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
546 
547 /*
548  * Version 2 or 3 client destruction
549  */
550 static void nfs_destroy_server(struct nfs_server *server)
551 {
552 	if (server->nlm_host)
553 		nlmclnt_done(server->nlm_host);
554 }
555 
556 /*
557  * Version 2 or 3 lockd setup
558  */
559 static int nfs_start_lockd(struct nfs_server *server)
560 {
561 	struct nlm_host *host;
562 	struct nfs_client *clp = server->nfs_client;
563 	struct nlmclnt_initdata nlm_init = {
564 		.hostname	= clp->cl_hostname,
565 		.address	= (struct sockaddr *)&clp->cl_addr,
566 		.addrlen	= clp->cl_addrlen,
567 		.nfs_version	= clp->rpc_ops->version,
568 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
569 					1 : 0,
570 		.net		= clp->cl_net,
571 		.nlmclnt_ops 	= clp->cl_nfs_mod->rpc_ops->nlmclnt_ops,
572 		.cred		= current_cred(),
573 	};
574 
575 	if (nlm_init.nfs_version > 3)
576 		return 0;
577 	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
578 			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
579 		return 0;
580 
581 	switch (clp->cl_proto) {
582 		default:
583 			nlm_init.protocol = IPPROTO_TCP;
584 			break;
585 #ifndef CONFIG_NFS_DISABLE_UDP_SUPPORT
586 		case XPRT_TRANSPORT_UDP:
587 			nlm_init.protocol = IPPROTO_UDP;
588 #endif
589 	}
590 
591 	host = nlmclnt_init(&nlm_init);
592 	if (IS_ERR(host))
593 		return PTR_ERR(host);
594 
595 	server->nlm_host = host;
596 	server->destroy = nfs_destroy_server;
597 	return 0;
598 }
599 
600 /*
601  * Create a general RPC client
602  */
603 int nfs_init_server_rpcclient(struct nfs_server *server,
604 		const struct rpc_timeout *timeo,
605 		rpc_authflavor_t pseudoflavour)
606 {
607 	struct nfs_client *clp = server->nfs_client;
608 
609 	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
610 							pseudoflavour);
611 	if (IS_ERR(server->client)) {
612 		dprintk("%s: couldn't create rpc_client!\n", __func__);
613 		return PTR_ERR(server->client);
614 	}
615 
616 	memcpy(&server->client->cl_timeout_default,
617 			timeo,
618 			sizeof(server->client->cl_timeout_default));
619 	server->client->cl_timeout = &server->client->cl_timeout_default;
620 	server->client->cl_softrtry = 0;
621 	if (server->flags & NFS_MOUNT_SOFTERR)
622 		server->client->cl_softerr = 1;
623 	if (server->flags & NFS_MOUNT_SOFT)
624 		server->client->cl_softrtry = 1;
625 
626 	return 0;
627 }
628 EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
629 
630 /**
631  * nfs_init_client - Initialise an NFS2 or NFS3 client
632  *
633  * @clp: nfs_client to initialise
634  * @cl_init: Initialisation parameters
635  *
636  * Returns pointer to an NFS client, or an ERR_PTR value.
637  */
638 struct nfs_client *nfs_init_client(struct nfs_client *clp,
639 				   const struct nfs_client_initdata *cl_init)
640 {
641 	int error;
642 
643 	/* the client is already initialised */
644 	if (clp->cl_cons_state == NFS_CS_READY)
645 		return clp;
646 
647 	/*
648 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
649 	 * - RFC 2623, sec 2.3.2
650 	 */
651 	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
652 	nfs_mark_client_ready(clp, error == 0 ? NFS_CS_READY : error);
653 	if (error < 0) {
654 		nfs_put_client(clp);
655 		clp = ERR_PTR(error);
656 	}
657 	return clp;
658 }
659 EXPORT_SYMBOL_GPL(nfs_init_client);
660 
661 /*
662  * Create a version 2 or 3 client
663  */
664 static int nfs_init_server(struct nfs_server *server,
665 			   const struct fs_context *fc)
666 {
667 	const struct nfs_fs_context *ctx = nfs_fc2context(fc);
668 	struct rpc_timeout timeparms;
669 	struct nfs_client_initdata cl_init = {
670 		.hostname = ctx->nfs_server.hostname,
671 		.addr = (const struct sockaddr *)&ctx->nfs_server.address,
672 		.addrlen = ctx->nfs_server.addrlen,
673 		.nfs_mod = ctx->nfs_mod,
674 		.proto = ctx->nfs_server.protocol,
675 		.net = fc->net_ns,
676 		.timeparms = &timeparms,
677 		.cred = server->cred,
678 		.nconnect = ctx->nfs_server.nconnect,
679 		.init_flags = (1UL << NFS_CS_REUSEPORT),
680 	};
681 	struct nfs_client *clp;
682 	int error;
683 
684 	nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
685 				ctx->timeo, ctx->retrans);
686 	if (ctx->flags & NFS_MOUNT_NORESVPORT)
687 		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
688 
689 	/* Allocate or find a client reference we can use */
690 	clp = nfs_get_client(&cl_init);
691 	if (IS_ERR(clp))
692 		return PTR_ERR(clp);
693 
694 	server->nfs_client = clp;
695 
696 	/* Initialise the client representation from the mount data */
697 	server->flags = ctx->flags;
698 	server->options = ctx->options;
699 	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
700 		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
701 		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
702 
703 	if (ctx->rsize)
704 		server->rsize = nfs_block_size(ctx->rsize, NULL);
705 	if (ctx->wsize)
706 		server->wsize = nfs_block_size(ctx->wsize, NULL);
707 
708 	server->acregmin = ctx->acregmin * HZ;
709 	server->acregmax = ctx->acregmax * HZ;
710 	server->acdirmin = ctx->acdirmin * HZ;
711 	server->acdirmax = ctx->acdirmax * HZ;
712 
713 	/* Start lockd here, before we might error out */
714 	error = nfs_start_lockd(server);
715 	if (error < 0)
716 		goto error;
717 
718 	server->port = ctx->nfs_server.port;
719 	server->auth_info = ctx->auth_info;
720 
721 	error = nfs_init_server_rpcclient(server, &timeparms,
722 					  ctx->selected_flavor);
723 	if (error < 0)
724 		goto error;
725 
726 	/* Preserve the values of mount_server-related mount options */
727 	if (ctx->mount_server.addrlen) {
728 		memcpy(&server->mountd_address, &ctx->mount_server.address,
729 			ctx->mount_server.addrlen);
730 		server->mountd_addrlen = ctx->mount_server.addrlen;
731 	}
732 	server->mountd_version = ctx->mount_server.version;
733 	server->mountd_port = ctx->mount_server.port;
734 	server->mountd_protocol = ctx->mount_server.protocol;
735 
736 	server->namelen  = ctx->namlen;
737 	return 0;
738 
739 error:
740 	server->nfs_client = NULL;
741 	nfs_put_client(clp);
742 	return error;
743 }
744 
745 /*
746  * Load up the server record from information gained in an fsinfo record
747  */
748 static void nfs_server_set_fsinfo(struct nfs_server *server,
749 				  struct nfs_fsinfo *fsinfo)
750 {
751 	unsigned long max_rpc_payload;
752 
753 	/* Work out a lot of parameters */
754 	if (server->rsize == 0)
755 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
756 	if (server->wsize == 0)
757 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
758 
759 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
760 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
761 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
762 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
763 
764 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
765 	if (server->rsize > max_rpc_payload)
766 		server->rsize = max_rpc_payload;
767 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
768 		server->rsize = NFS_MAX_FILE_IO_SIZE;
769 	server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
770 
771 	if (server->wsize > max_rpc_payload)
772 		server->wsize = max_rpc_payload;
773 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
774 		server->wsize = NFS_MAX_FILE_IO_SIZE;
775 	server->wpages = (server->wsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
776 
777 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
778 
779 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
780 	if (server->dtsize > PAGE_SIZE * NFS_MAX_READDIR_PAGES)
781 		server->dtsize = PAGE_SIZE * NFS_MAX_READDIR_PAGES;
782 	if (server->dtsize > server->rsize)
783 		server->dtsize = server->rsize;
784 
785 	if (server->flags & NFS_MOUNT_NOAC) {
786 		server->acregmin = server->acregmax = 0;
787 		server->acdirmin = server->acdirmax = 0;
788 	}
789 
790 	server->maxfilesize = fsinfo->maxfilesize;
791 
792 	server->time_delta = fsinfo->time_delta;
793 
794 	server->clone_blksize = fsinfo->clone_blksize;
795 	/* We're airborne Set socket buffersize */
796 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
797 }
798 
799 /*
800  * Probe filesystem information, including the FSID on v2/v3
801  */
802 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
803 {
804 	struct nfs_fsinfo fsinfo;
805 	struct nfs_client *clp = server->nfs_client;
806 	int error;
807 
808 	if (clp->rpc_ops->set_capabilities != NULL) {
809 		error = clp->rpc_ops->set_capabilities(server, mntfh);
810 		if (error < 0)
811 			return error;
812 	}
813 
814 	fsinfo.fattr = fattr;
815 	fsinfo.nlayouttypes = 0;
816 	memset(fsinfo.layouttype, 0, sizeof(fsinfo.layouttype));
817 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
818 	if (error < 0)
819 		return error;
820 
821 	nfs_server_set_fsinfo(server, &fsinfo);
822 
823 	/* Get some general file system info */
824 	if (server->namelen == 0) {
825 		struct nfs_pathconf pathinfo;
826 
827 		pathinfo.fattr = fattr;
828 		nfs_fattr_init(fattr);
829 
830 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
831 			server->namelen = pathinfo.max_namelen;
832 	}
833 
834 	return 0;
835 }
836 EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
837 
838 /*
839  * Copy useful information when duplicating a server record
840  */
841 void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
842 {
843 	target->flags = source->flags;
844 	target->rsize = source->rsize;
845 	target->wsize = source->wsize;
846 	target->acregmin = source->acregmin;
847 	target->acregmax = source->acregmax;
848 	target->acdirmin = source->acdirmin;
849 	target->acdirmax = source->acdirmax;
850 	target->caps = source->caps;
851 	target->options = source->options;
852 	target->auth_info = source->auth_info;
853 	target->port = source->port;
854 }
855 EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
856 
857 void nfs_server_insert_lists(struct nfs_server *server)
858 {
859 	struct nfs_client *clp = server->nfs_client;
860 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
861 
862 	spin_lock(&nn->nfs_client_lock);
863 	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
864 	list_add_tail(&server->master_link, &nn->nfs_volume_list);
865 	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
866 	spin_unlock(&nn->nfs_client_lock);
867 
868 }
869 EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
870 
871 void nfs_server_remove_lists(struct nfs_server *server)
872 {
873 	struct nfs_client *clp = server->nfs_client;
874 	struct nfs_net *nn;
875 
876 	if (clp == NULL)
877 		return;
878 	nn = net_generic(clp->cl_net, nfs_net_id);
879 	spin_lock(&nn->nfs_client_lock);
880 	list_del_rcu(&server->client_link);
881 	if (list_empty(&clp->cl_superblocks))
882 		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
883 	list_del(&server->master_link);
884 	spin_unlock(&nn->nfs_client_lock);
885 
886 	synchronize_rcu();
887 }
888 EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
889 
890 /*
891  * Allocate and initialise a server record
892  */
893 struct nfs_server *nfs_alloc_server(void)
894 {
895 	struct nfs_server *server;
896 
897 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
898 	if (!server)
899 		return NULL;
900 
901 	server->client = server->client_acl = ERR_PTR(-EINVAL);
902 
903 	/* Zero out the NFS state stuff */
904 	INIT_LIST_HEAD(&server->client_link);
905 	INIT_LIST_HEAD(&server->master_link);
906 	INIT_LIST_HEAD(&server->delegations);
907 	INIT_LIST_HEAD(&server->layouts);
908 	INIT_LIST_HEAD(&server->state_owners_lru);
909 	INIT_LIST_HEAD(&server->ss_copies);
910 
911 	atomic_set(&server->active, 0);
912 
913 	server->io_stats = nfs_alloc_iostats();
914 	if (!server->io_stats) {
915 		kfree(server);
916 		return NULL;
917 	}
918 
919 	ida_init(&server->openowner_id);
920 	ida_init(&server->lockowner_id);
921 	pnfs_init_server(server);
922 	rpc_init_wait_queue(&server->uoc_rpcwaitq, "NFS UOC");
923 
924 	return server;
925 }
926 EXPORT_SYMBOL_GPL(nfs_alloc_server);
927 
928 /*
929  * Free up a server record
930  */
931 void nfs_free_server(struct nfs_server *server)
932 {
933 	nfs_server_remove_lists(server);
934 
935 	if (server->destroy != NULL)
936 		server->destroy(server);
937 
938 	if (!IS_ERR(server->client_acl))
939 		rpc_shutdown_client(server->client_acl);
940 	if (!IS_ERR(server->client))
941 		rpc_shutdown_client(server->client);
942 
943 	nfs_put_client(server->nfs_client);
944 
945 	ida_destroy(&server->lockowner_id);
946 	ida_destroy(&server->openowner_id);
947 	nfs_free_iostats(server->io_stats);
948 	put_cred(server->cred);
949 	kfree(server);
950 	nfs_release_automount_timer();
951 }
952 EXPORT_SYMBOL_GPL(nfs_free_server);
953 
954 /*
955  * Create a version 2 or 3 volume record
956  * - keyed on server and FSID
957  */
958 struct nfs_server *nfs_create_server(struct fs_context *fc)
959 {
960 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
961 	struct nfs_server *server;
962 	struct nfs_fattr *fattr;
963 	int error;
964 
965 	server = nfs_alloc_server();
966 	if (!server)
967 		return ERR_PTR(-ENOMEM);
968 
969 	server->cred = get_cred(current_cred());
970 
971 	error = -ENOMEM;
972 	fattr = nfs_alloc_fattr();
973 	if (fattr == NULL)
974 		goto error;
975 
976 	/* Get a client representation */
977 	error = nfs_init_server(server, fc);
978 	if (error < 0)
979 		goto error;
980 
981 	/* Probe the root fh to retrieve its FSID */
982 	error = nfs_probe_fsinfo(server, ctx->mntfh, fattr);
983 	if (error < 0)
984 		goto error;
985 	if (server->nfs_client->rpc_ops->version == 3) {
986 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
987 			server->namelen = NFS3_MAXNAMLEN;
988 		if (!(ctx->flags & NFS_MOUNT_NORDIRPLUS))
989 			server->caps |= NFS_CAP_READDIRPLUS;
990 	} else {
991 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
992 			server->namelen = NFS2_MAXNAMLEN;
993 	}
994 
995 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
996 		error = ctx->nfs_mod->rpc_ops->getattr(server, ctx->mntfh,
997 						       fattr, NULL, NULL);
998 		if (error < 0) {
999 			dprintk("nfs_create_server: getattr error = %d\n", -error);
1000 			goto error;
1001 		}
1002 	}
1003 	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1004 
1005 	dprintk("Server FSID: %llx:%llx\n",
1006 		(unsigned long long) server->fsid.major,
1007 		(unsigned long long) server->fsid.minor);
1008 
1009 	nfs_server_insert_lists(server);
1010 	server->mount_time = jiffies;
1011 	nfs_free_fattr(fattr);
1012 	return server;
1013 
1014 error:
1015 	nfs_free_fattr(fattr);
1016 	nfs_free_server(server);
1017 	return ERR_PTR(error);
1018 }
1019 EXPORT_SYMBOL_GPL(nfs_create_server);
1020 
1021 /*
1022  * Clone an NFS2, NFS3 or NFS4 server record
1023  */
1024 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1025 				    struct nfs_fh *fh,
1026 				    struct nfs_fattr *fattr,
1027 				    rpc_authflavor_t flavor)
1028 {
1029 	struct nfs_server *server;
1030 	struct nfs_fattr *fattr_fsinfo;
1031 	int error;
1032 
1033 	server = nfs_alloc_server();
1034 	if (!server)
1035 		return ERR_PTR(-ENOMEM);
1036 
1037 	server->cred = get_cred(source->cred);
1038 
1039 	error = -ENOMEM;
1040 	fattr_fsinfo = nfs_alloc_fattr();
1041 	if (fattr_fsinfo == NULL)
1042 		goto out_free_server;
1043 
1044 	/* Copy data from the source */
1045 	server->nfs_client = source->nfs_client;
1046 	server->destroy = source->destroy;
1047 	refcount_inc(&server->nfs_client->cl_count);
1048 	nfs_server_copy_userdata(server, source);
1049 
1050 	server->fsid = fattr->fsid;
1051 
1052 	error = nfs_init_server_rpcclient(server,
1053 			source->client->cl_timeout,
1054 			flavor);
1055 	if (error < 0)
1056 		goto out_free_server;
1057 
1058 	/* probe the filesystem info for this server filesystem */
1059 	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1060 	if (error < 0)
1061 		goto out_free_server;
1062 
1063 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1064 		server->namelen = NFS4_MAXNAMLEN;
1065 
1066 	error = nfs_start_lockd(server);
1067 	if (error < 0)
1068 		goto out_free_server;
1069 
1070 	nfs_server_insert_lists(server);
1071 	server->mount_time = jiffies;
1072 
1073 	nfs_free_fattr(fattr_fsinfo);
1074 	return server;
1075 
1076 out_free_server:
1077 	nfs_free_fattr(fattr_fsinfo);
1078 	nfs_free_server(server);
1079 	return ERR_PTR(error);
1080 }
1081 EXPORT_SYMBOL_GPL(nfs_clone_server);
1082 
1083 void nfs_clients_init(struct net *net)
1084 {
1085 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1086 
1087 	INIT_LIST_HEAD(&nn->nfs_client_list);
1088 	INIT_LIST_HEAD(&nn->nfs_volume_list);
1089 #if IS_ENABLED(CONFIG_NFS_V4)
1090 	idr_init(&nn->cb_ident_idr);
1091 #endif
1092 	spin_lock_init(&nn->nfs_client_lock);
1093 	nn->boot_time = ktime_get_real();
1094 
1095 	nfs_netns_sysfs_setup(nn, net);
1096 }
1097 
1098 void nfs_clients_exit(struct net *net)
1099 {
1100 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1101 
1102 	nfs_netns_sysfs_destroy(nn);
1103 	nfs_cleanup_cb_ident_idr(net);
1104 	WARN_ON_ONCE(!list_empty(&nn->nfs_client_list));
1105 	WARN_ON_ONCE(!list_empty(&nn->nfs_volume_list));
1106 }
1107 
1108 #ifdef CONFIG_PROC_FS
1109 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1110 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1111 static void nfs_server_list_stop(struct seq_file *p, void *v);
1112 static int nfs_server_list_show(struct seq_file *m, void *v);
1113 
1114 static const struct seq_operations nfs_server_list_ops = {
1115 	.start	= nfs_server_list_start,
1116 	.next	= nfs_server_list_next,
1117 	.stop	= nfs_server_list_stop,
1118 	.show	= nfs_server_list_show,
1119 };
1120 
1121 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1122 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1123 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1124 static int nfs_volume_list_show(struct seq_file *m, void *v);
1125 
1126 static const struct seq_operations nfs_volume_list_ops = {
1127 	.start	= nfs_volume_list_start,
1128 	.next	= nfs_volume_list_next,
1129 	.stop	= nfs_volume_list_stop,
1130 	.show	= nfs_volume_list_show,
1131 };
1132 
1133 /*
1134  * set up the iterator to start reading from the server list and return the first item
1135  */
1136 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1137 				__acquires(&nn->nfs_client_lock)
1138 {
1139 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1140 
1141 	/* lock the list against modification */
1142 	spin_lock(&nn->nfs_client_lock);
1143 	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1144 }
1145 
1146 /*
1147  * move to next server
1148  */
1149 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1150 {
1151 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1152 
1153 	return seq_list_next(v, &nn->nfs_client_list, pos);
1154 }
1155 
1156 /*
1157  * clean up after reading from the transports list
1158  */
1159 static void nfs_server_list_stop(struct seq_file *p, void *v)
1160 				__releases(&nn->nfs_client_lock)
1161 {
1162 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1163 
1164 	spin_unlock(&nn->nfs_client_lock);
1165 }
1166 
1167 /*
1168  * display a header line followed by a load of call lines
1169  */
1170 static int nfs_server_list_show(struct seq_file *m, void *v)
1171 {
1172 	struct nfs_client *clp;
1173 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1174 
1175 	/* display header on line 1 */
1176 	if (v == &nn->nfs_client_list) {
1177 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1178 		return 0;
1179 	}
1180 
1181 	/* display one transport per line on subsequent lines */
1182 	clp = list_entry(v, struct nfs_client, cl_share_link);
1183 
1184 	/* Check if the client is initialized */
1185 	if (clp->cl_cons_state != NFS_CS_READY)
1186 		return 0;
1187 
1188 	rcu_read_lock();
1189 	seq_printf(m, "v%u %s %s %3d %s\n",
1190 		   clp->rpc_ops->version,
1191 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1192 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1193 		   refcount_read(&clp->cl_count),
1194 		   clp->cl_hostname);
1195 	rcu_read_unlock();
1196 
1197 	return 0;
1198 }
1199 
1200 /*
1201  * set up the iterator to start reading from the volume list and return the first item
1202  */
1203 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1204 				__acquires(&nn->nfs_client_lock)
1205 {
1206 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1207 
1208 	/* lock the list against modification */
1209 	spin_lock(&nn->nfs_client_lock);
1210 	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1211 }
1212 
1213 /*
1214  * move to next volume
1215  */
1216 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1217 {
1218 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1219 
1220 	return seq_list_next(v, &nn->nfs_volume_list, pos);
1221 }
1222 
1223 /*
1224  * clean up after reading from the transports list
1225  */
1226 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1227 				__releases(&nn->nfs_client_lock)
1228 {
1229 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1230 
1231 	spin_unlock(&nn->nfs_client_lock);
1232 }
1233 
1234 /*
1235  * display a header line followed by a load of call lines
1236  */
1237 static int nfs_volume_list_show(struct seq_file *m, void *v)
1238 {
1239 	struct nfs_server *server;
1240 	struct nfs_client *clp;
1241 	char dev[13];	// 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1242 	char fsid[34];	// 2 * 16 for %llx, 1 for ':', 1 for '\0'
1243 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1244 
1245 	/* display header on line 1 */
1246 	if (v == &nn->nfs_volume_list) {
1247 		seq_puts(m, "NV SERVER   PORT DEV          FSID"
1248 			    "                              FSC\n");
1249 		return 0;
1250 	}
1251 	/* display one transport per line on subsequent lines */
1252 	server = list_entry(v, struct nfs_server, master_link);
1253 	clp = server->nfs_client;
1254 
1255 	snprintf(dev, sizeof(dev), "%u:%u",
1256 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1257 
1258 	snprintf(fsid, sizeof(fsid), "%llx:%llx",
1259 		 (unsigned long long) server->fsid.major,
1260 		 (unsigned long long) server->fsid.minor);
1261 
1262 	rcu_read_lock();
1263 	seq_printf(m, "v%u %s %s %-12s %-33s %s\n",
1264 		   clp->rpc_ops->version,
1265 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1266 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1267 		   dev,
1268 		   fsid,
1269 		   nfs_server_fscache_state(server));
1270 	rcu_read_unlock();
1271 
1272 	return 0;
1273 }
1274 
1275 int nfs_fs_proc_net_init(struct net *net)
1276 {
1277 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1278 	struct proc_dir_entry *p;
1279 
1280 	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1281 	if (!nn->proc_nfsfs)
1282 		goto error_0;
1283 
1284 	/* a file of servers with which we're dealing */
1285 	p = proc_create_net("servers", S_IFREG|S_IRUGO, nn->proc_nfsfs,
1286 			&nfs_server_list_ops, sizeof(struct seq_net_private));
1287 	if (!p)
1288 		goto error_1;
1289 
1290 	/* a file of volumes that we have mounted */
1291 	p = proc_create_net("volumes", S_IFREG|S_IRUGO, nn->proc_nfsfs,
1292 			&nfs_volume_list_ops, sizeof(struct seq_net_private));
1293 	if (!p)
1294 		goto error_1;
1295 	return 0;
1296 
1297 error_1:
1298 	remove_proc_subtree("nfsfs", net->proc_net);
1299 error_0:
1300 	return -ENOMEM;
1301 }
1302 
1303 void nfs_fs_proc_net_exit(struct net *net)
1304 {
1305 	remove_proc_subtree("nfsfs", net->proc_net);
1306 }
1307 
1308 /*
1309  * initialise the /proc/fs/nfsfs/ directory
1310  */
1311 int __init nfs_fs_proc_init(void)
1312 {
1313 	if (!proc_mkdir("fs/nfsfs", NULL))
1314 		goto error_0;
1315 
1316 	/* a file of servers with which we're dealing */
1317 	if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1318 		goto error_1;
1319 
1320 	/* a file of volumes that we have mounted */
1321 	if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1322 		goto error_1;
1323 
1324 	return 0;
1325 error_1:
1326 	remove_proc_subtree("fs/nfsfs", NULL);
1327 error_0:
1328 	return -ENOMEM;
1329 }
1330 
1331 /*
1332  * clean up the /proc/fs/nfsfs/ directory
1333  */
1334 void nfs_fs_proc_exit(void)
1335 {
1336 	remove_proc_subtree("fs/nfsfs", NULL);
1337 }
1338 
1339 #endif /* CONFIG_PROC_FS */
1340