xref: /openbmc/linux/fs/nfs/client.c (revision 6dfcd296)
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 			/* Match all xprt_switch full socket addresses */
317 			if (!rpc_clnt_xprt_switch_has_addr(clp->cl_rpcclient,
318 							   sap))
319 				continue;
320 
321 		atomic_inc(&clp->cl_count);
322 		return clp;
323 	}
324 	return NULL;
325 }
326 
327 static bool nfs_client_init_is_complete(const struct nfs_client *clp)
328 {
329 	return clp->cl_cons_state <= NFS_CS_READY;
330 }
331 
332 int nfs_wait_client_init_complete(const struct nfs_client *clp)
333 {
334 	return wait_event_killable(nfs_client_active_wq,
335 			nfs_client_init_is_complete(clp));
336 }
337 EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
338 
339 /*
340  * Found an existing client.  Make sure it's ready before returning.
341  */
342 static struct nfs_client *
343 nfs_found_client(const struct nfs_client_initdata *cl_init,
344 		 struct nfs_client *clp)
345 {
346 	int error;
347 
348 	error = nfs_wait_client_init_complete(clp);
349 	if (error < 0) {
350 		nfs_put_client(clp);
351 		return ERR_PTR(-ERESTARTSYS);
352 	}
353 
354 	if (clp->cl_cons_state < NFS_CS_READY) {
355 		error = clp->cl_cons_state;
356 		nfs_put_client(clp);
357 		return ERR_PTR(error);
358 	}
359 
360 	smp_rmb();
361 
362 	dprintk("<-- %s found nfs_client %p for %s\n",
363 		__func__, clp, cl_init->hostname ?: "");
364 	return clp;
365 }
366 
367 /*
368  * Look up a client by IP address and protocol version
369  * - creates a new record if one doesn't yet exist
370  */
371 struct nfs_client *
372 nfs_get_client(const struct nfs_client_initdata *cl_init,
373 	       rpc_authflavor_t authflavour)
374 {
375 	struct nfs_client *clp, *new = NULL;
376 	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
377 	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
378 
379 	if (cl_init->hostname == NULL) {
380 		WARN_ON(1);
381 		return NULL;
382 	}
383 
384 	dprintk("--> nfs_get_client(%s,v%u)\n",
385 		cl_init->hostname, rpc_ops->version);
386 
387 	/* see if the client already exists */
388 	do {
389 		spin_lock(&nn->nfs_client_lock);
390 
391 		clp = nfs_match_client(cl_init);
392 		if (clp) {
393 			spin_unlock(&nn->nfs_client_lock);
394 			if (new)
395 				new->rpc_ops->free_client(new);
396 			return nfs_found_client(cl_init, clp);
397 		}
398 		if (new) {
399 			list_add_tail(&new->cl_share_link,
400 					&nn->nfs_client_list);
401 			spin_unlock(&nn->nfs_client_lock);
402 			new->cl_flags = cl_init->init_flags;
403 			return rpc_ops->init_client(new, cl_init);
404 		}
405 
406 		spin_unlock(&nn->nfs_client_lock);
407 
408 		new = rpc_ops->alloc_client(cl_init);
409 	} while (!IS_ERR(new));
410 
411 	dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
412 		cl_init->hostname, PTR_ERR(new));
413 	return new;
414 }
415 EXPORT_SYMBOL_GPL(nfs_get_client);
416 
417 /*
418  * Mark a server as ready or failed
419  */
420 void nfs_mark_client_ready(struct nfs_client *clp, int state)
421 {
422 	smp_wmb();
423 	clp->cl_cons_state = state;
424 	wake_up_all(&nfs_client_active_wq);
425 }
426 EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
427 
428 /*
429  * Initialise the timeout values for a connection
430  */
431 void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
432 				    int timeo, int retrans)
433 {
434 	to->to_initval = timeo * HZ / 10;
435 	to->to_retries = retrans;
436 
437 	switch (proto) {
438 	case XPRT_TRANSPORT_TCP:
439 	case XPRT_TRANSPORT_RDMA:
440 		if (retrans == NFS_UNSPEC_RETRANS)
441 			to->to_retries = NFS_DEF_TCP_RETRANS;
442 		if (timeo == NFS_UNSPEC_TIMEO || to->to_retries == 0)
443 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
444 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
445 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
446 		to->to_increment = to->to_initval;
447 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
448 		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
449 			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
450 		if (to->to_maxval < to->to_initval)
451 			to->to_maxval = to->to_initval;
452 		to->to_exponential = 0;
453 		break;
454 	case XPRT_TRANSPORT_UDP:
455 		if (retrans == NFS_UNSPEC_RETRANS)
456 			to->to_retries = NFS_DEF_UDP_RETRANS;
457 		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
458 			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
459 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
460 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
461 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
462 		to->to_exponential = 1;
463 		break;
464 	default:
465 		BUG();
466 	}
467 }
468 EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
469 
470 /*
471  * Create an RPC client handle
472  */
473 int nfs_create_rpc_client(struct nfs_client *clp,
474 			  const struct nfs_client_initdata *cl_init,
475 			  rpc_authflavor_t flavor)
476 {
477 	struct rpc_clnt		*clnt = NULL;
478 	struct rpc_create_args args = {
479 		.net		= clp->cl_net,
480 		.protocol	= clp->cl_proto,
481 		.address	= (struct sockaddr *)&clp->cl_addr,
482 		.addrsize	= clp->cl_addrlen,
483 		.timeout	= cl_init->timeparms,
484 		.servername	= clp->cl_hostname,
485 		.nodename	= cl_init->nodename,
486 		.program	= &nfs_program,
487 		.version	= clp->rpc_ops->version,
488 		.authflavor	= flavor,
489 	};
490 
491 	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
492 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
493 	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
494 		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
495 	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
496 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
497 	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
498 		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
499 
500 	if (!IS_ERR(clp->cl_rpcclient))
501 		return 0;
502 
503 	clnt = rpc_create(&args);
504 	if (IS_ERR(clnt)) {
505 		dprintk("%s: cannot create RPC client. Error = %ld\n",
506 				__func__, PTR_ERR(clnt));
507 		return PTR_ERR(clnt);
508 	}
509 
510 	clp->cl_rpcclient = clnt;
511 	return 0;
512 }
513 EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
514 
515 /*
516  * Version 2 or 3 client destruction
517  */
518 static void nfs_destroy_server(struct nfs_server *server)
519 {
520 	if (server->nlm_host)
521 		nlmclnt_done(server->nlm_host);
522 }
523 
524 /*
525  * Version 2 or 3 lockd setup
526  */
527 static int nfs_start_lockd(struct nfs_server *server)
528 {
529 	struct nlm_host *host;
530 	struct nfs_client *clp = server->nfs_client;
531 	struct nlmclnt_initdata nlm_init = {
532 		.hostname	= clp->cl_hostname,
533 		.address	= (struct sockaddr *)&clp->cl_addr,
534 		.addrlen	= clp->cl_addrlen,
535 		.nfs_version	= clp->rpc_ops->version,
536 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
537 					1 : 0,
538 		.net		= clp->cl_net,
539 	};
540 
541 	if (nlm_init.nfs_version > 3)
542 		return 0;
543 	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
544 			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
545 		return 0;
546 
547 	switch (clp->cl_proto) {
548 		default:
549 			nlm_init.protocol = IPPROTO_TCP;
550 			break;
551 		case XPRT_TRANSPORT_UDP:
552 			nlm_init.protocol = IPPROTO_UDP;
553 	}
554 
555 	host = nlmclnt_init(&nlm_init);
556 	if (IS_ERR(host))
557 		return PTR_ERR(host);
558 
559 	server->nlm_host = host;
560 	server->destroy = nfs_destroy_server;
561 	return 0;
562 }
563 
564 /*
565  * Create a general RPC client
566  */
567 int nfs_init_server_rpcclient(struct nfs_server *server,
568 		const struct rpc_timeout *timeo,
569 		rpc_authflavor_t pseudoflavour)
570 {
571 	struct nfs_client *clp = server->nfs_client;
572 
573 	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
574 							pseudoflavour);
575 	if (IS_ERR(server->client)) {
576 		dprintk("%s: couldn't create rpc_client!\n", __func__);
577 		return PTR_ERR(server->client);
578 	}
579 
580 	memcpy(&server->client->cl_timeout_default,
581 			timeo,
582 			sizeof(server->client->cl_timeout_default));
583 	server->client->cl_timeout = &server->client->cl_timeout_default;
584 	server->client->cl_softrtry = 0;
585 	if (server->flags & NFS_MOUNT_SOFT)
586 		server->client->cl_softrtry = 1;
587 
588 	return 0;
589 }
590 EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
591 
592 /**
593  * nfs_init_client - Initialise an NFS2 or NFS3 client
594  *
595  * @clp: nfs_client to initialise
596  * @cl_init: Initialisation parameters
597  *
598  * Returns pointer to an NFS client, or an ERR_PTR value.
599  */
600 struct nfs_client *nfs_init_client(struct nfs_client *clp,
601 				   const struct nfs_client_initdata *cl_init)
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, cl_init, 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 rpc_timeout timeparms;
637 	struct nfs_client_initdata cl_init = {
638 		.hostname = data->nfs_server.hostname,
639 		.addr = (const struct sockaddr *)&data->nfs_server.address,
640 		.addrlen = data->nfs_server.addrlen,
641 		.nfs_mod = nfs_mod,
642 		.proto = data->nfs_server.protocol,
643 		.net = data->net,
644 		.timeparms = &timeparms,
645 	};
646 	struct nfs_client *clp;
647 	int error;
648 
649 	dprintk("--> nfs_init_server()\n");
650 
651 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
652 			data->timeo, data->retrans);
653 	if (data->flags & NFS_MOUNT_NORESVPORT)
654 		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
655 
656 	/* Allocate or find a client reference we can use */
657 	clp = nfs_get_client(&cl_init, RPC_AUTH_UNIX);
658 	if (IS_ERR(clp)) {
659 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
660 		return PTR_ERR(clp);
661 	}
662 
663 	server->nfs_client = clp;
664 
665 	/* Initialise the client representation from the mount data */
666 	server->flags = data->flags;
667 	server->options = data->options;
668 	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
669 		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
670 		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
671 
672 	if (data->rsize)
673 		server->rsize = nfs_block_size(data->rsize, NULL);
674 	if (data->wsize)
675 		server->wsize = nfs_block_size(data->wsize, NULL);
676 
677 	server->acregmin = data->acregmin * HZ;
678 	server->acregmax = data->acregmax * HZ;
679 	server->acdirmin = data->acdirmin * HZ;
680 	server->acdirmax = data->acdirmax * HZ;
681 
682 	/* Start lockd here, before we might error out */
683 	error = nfs_start_lockd(server);
684 	if (error < 0)
685 		goto error;
686 
687 	server->port = data->nfs_server.port;
688 	server->auth_info = data->auth_info;
689 
690 	error = nfs_init_server_rpcclient(server, &timeparms,
691 					  data->selected_flavor);
692 	if (error < 0)
693 		goto error;
694 
695 	/* Preserve the values of mount_server-related mount options */
696 	if (data->mount_server.addrlen) {
697 		memcpy(&server->mountd_address, &data->mount_server.address,
698 			data->mount_server.addrlen);
699 		server->mountd_addrlen = data->mount_server.addrlen;
700 	}
701 	server->mountd_version = data->mount_server.version;
702 	server->mountd_port = data->mount_server.port;
703 	server->mountd_protocol = data->mount_server.protocol;
704 
705 	server->namelen  = data->namlen;
706 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
707 	return 0;
708 
709 error:
710 	server->nfs_client = NULL;
711 	nfs_put_client(clp);
712 	dprintk("<-- nfs_init_server() = xerror %d\n", error);
713 	return error;
714 }
715 
716 /*
717  * Load up the server record from information gained in an fsinfo record
718  */
719 static void nfs_server_set_fsinfo(struct nfs_server *server,
720 				  struct nfs_fsinfo *fsinfo)
721 {
722 	unsigned long max_rpc_payload;
723 
724 	/* Work out a lot of parameters */
725 	if (server->rsize == 0)
726 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
727 	if (server->wsize == 0)
728 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
729 
730 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
731 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
732 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
733 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
734 
735 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
736 	if (server->rsize > max_rpc_payload)
737 		server->rsize = max_rpc_payload;
738 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
739 		server->rsize = NFS_MAX_FILE_IO_SIZE;
740 	server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
741 
742 	server->backing_dev_info.name = "nfs";
743 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
744 
745 	if (server->wsize > max_rpc_payload)
746 		server->wsize = max_rpc_payload;
747 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
748 		server->wsize = NFS_MAX_FILE_IO_SIZE;
749 	server->wpages = (server->wsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
750 
751 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
752 
753 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
754 	if (server->dtsize > PAGE_SIZE * NFS_MAX_READDIR_PAGES)
755 		server->dtsize = PAGE_SIZE * NFS_MAX_READDIR_PAGES;
756 	if (server->dtsize > server->rsize)
757 		server->dtsize = server->rsize;
758 
759 	if (server->flags & NFS_MOUNT_NOAC) {
760 		server->acregmin = server->acregmax = 0;
761 		server->acdirmin = server->acdirmax = 0;
762 	}
763 
764 	server->maxfilesize = fsinfo->maxfilesize;
765 
766 	server->time_delta = fsinfo->time_delta;
767 
768 	server->clone_blksize = fsinfo->clone_blksize;
769 	/* We're airborne Set socket buffersize */
770 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
771 }
772 
773 /*
774  * Probe filesystem information, including the FSID on v2/v3
775  */
776 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
777 {
778 	struct nfs_fsinfo fsinfo;
779 	struct nfs_client *clp = server->nfs_client;
780 	int error;
781 
782 	dprintk("--> nfs_probe_fsinfo()\n");
783 
784 	if (clp->rpc_ops->set_capabilities != NULL) {
785 		error = clp->rpc_ops->set_capabilities(server, mntfh);
786 		if (error < 0)
787 			goto out_error;
788 	}
789 
790 	fsinfo.fattr = fattr;
791 	fsinfo.nlayouttypes = 0;
792 	memset(fsinfo.layouttype, 0, sizeof(fsinfo.layouttype));
793 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
794 	if (error < 0)
795 		goto out_error;
796 
797 	nfs_server_set_fsinfo(server, &fsinfo);
798 
799 	/* Get some general file system info */
800 	if (server->namelen == 0) {
801 		struct nfs_pathconf pathinfo;
802 
803 		pathinfo.fattr = fattr;
804 		nfs_fattr_init(fattr);
805 
806 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
807 			server->namelen = pathinfo.max_namelen;
808 	}
809 
810 	dprintk("<-- nfs_probe_fsinfo() = 0\n");
811 	return 0;
812 
813 out_error:
814 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
815 	return error;
816 }
817 EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
818 
819 /*
820  * Copy useful information when duplicating a server record
821  */
822 void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
823 {
824 	target->flags = source->flags;
825 	target->rsize = source->rsize;
826 	target->wsize = source->wsize;
827 	target->acregmin = source->acregmin;
828 	target->acregmax = source->acregmax;
829 	target->acdirmin = source->acdirmin;
830 	target->acdirmax = source->acdirmax;
831 	target->caps = source->caps;
832 	target->options = source->options;
833 	target->auth_info = source->auth_info;
834 }
835 EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
836 
837 void nfs_server_insert_lists(struct nfs_server *server)
838 {
839 	struct nfs_client *clp = server->nfs_client;
840 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
841 
842 	spin_lock(&nn->nfs_client_lock);
843 	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
844 	list_add_tail(&server->master_link, &nn->nfs_volume_list);
845 	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
846 	spin_unlock(&nn->nfs_client_lock);
847 
848 }
849 EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
850 
851 void nfs_server_remove_lists(struct nfs_server *server)
852 {
853 	struct nfs_client *clp = server->nfs_client;
854 	struct nfs_net *nn;
855 
856 	if (clp == NULL)
857 		return;
858 	nn = net_generic(clp->cl_net, nfs_net_id);
859 	spin_lock(&nn->nfs_client_lock);
860 	list_del_rcu(&server->client_link);
861 	if (list_empty(&clp->cl_superblocks))
862 		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
863 	list_del(&server->master_link);
864 	spin_unlock(&nn->nfs_client_lock);
865 
866 	synchronize_rcu();
867 }
868 EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
869 
870 /*
871  * Allocate and initialise a server record
872  */
873 struct nfs_server *nfs_alloc_server(void)
874 {
875 	struct nfs_server *server;
876 
877 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
878 	if (!server)
879 		return NULL;
880 
881 	server->client = server->client_acl = ERR_PTR(-EINVAL);
882 
883 	/* Zero out the NFS state stuff */
884 	INIT_LIST_HEAD(&server->client_link);
885 	INIT_LIST_HEAD(&server->master_link);
886 	INIT_LIST_HEAD(&server->delegations);
887 	INIT_LIST_HEAD(&server->layouts);
888 	INIT_LIST_HEAD(&server->state_owners_lru);
889 
890 	atomic_set(&server->active, 0);
891 
892 	server->io_stats = nfs_alloc_iostats();
893 	if (!server->io_stats) {
894 		kfree(server);
895 		return NULL;
896 	}
897 
898 	if (bdi_init(&server->backing_dev_info)) {
899 		nfs_free_iostats(server->io_stats);
900 		kfree(server);
901 		return NULL;
902 	}
903 
904 	ida_init(&server->openowner_id);
905 	ida_init(&server->lockowner_id);
906 	pnfs_init_server(server);
907 
908 	return server;
909 }
910 EXPORT_SYMBOL_GPL(nfs_alloc_server);
911 
912 /*
913  * Free up a server record
914  */
915 void nfs_free_server(struct nfs_server *server)
916 {
917 	dprintk("--> nfs_free_server()\n");
918 
919 	nfs_server_remove_lists(server);
920 
921 	if (server->destroy != NULL)
922 		server->destroy(server);
923 
924 	if (!IS_ERR(server->client_acl))
925 		rpc_shutdown_client(server->client_acl);
926 	if (!IS_ERR(server->client))
927 		rpc_shutdown_client(server->client);
928 
929 	nfs_put_client(server->nfs_client);
930 
931 	ida_destroy(&server->lockowner_id);
932 	ida_destroy(&server->openowner_id);
933 	nfs_free_iostats(server->io_stats);
934 	bdi_destroy(&server->backing_dev_info);
935 	kfree(server);
936 	nfs_release_automount_timer();
937 	dprintk("<-- nfs_free_server()\n");
938 }
939 EXPORT_SYMBOL_GPL(nfs_free_server);
940 
941 /*
942  * Create a version 2 or 3 volume record
943  * - keyed on server and FSID
944  */
945 struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
946 				     struct nfs_subversion *nfs_mod)
947 {
948 	struct nfs_server *server;
949 	struct nfs_fattr *fattr;
950 	int error;
951 
952 	server = nfs_alloc_server();
953 	if (!server)
954 		return ERR_PTR(-ENOMEM);
955 
956 	error = -ENOMEM;
957 	fattr = nfs_alloc_fattr();
958 	if (fattr == NULL)
959 		goto error;
960 
961 	/* Get a client representation */
962 	error = nfs_init_server(server, mount_info->parsed, nfs_mod);
963 	if (error < 0)
964 		goto error;
965 
966 	/* Probe the root fh to retrieve its FSID */
967 	error = nfs_probe_fsinfo(server, mount_info->mntfh, fattr);
968 	if (error < 0)
969 		goto error;
970 	if (server->nfs_client->rpc_ops->version == 3) {
971 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
972 			server->namelen = NFS3_MAXNAMLEN;
973 		if (!(mount_info->parsed->flags & NFS_MOUNT_NORDIRPLUS))
974 			server->caps |= NFS_CAP_READDIRPLUS;
975 	} else {
976 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
977 			server->namelen = NFS2_MAXNAMLEN;
978 	}
979 
980 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
981 		error = nfs_mod->rpc_ops->getattr(server, mount_info->mntfh, fattr, NULL);
982 		if (error < 0) {
983 			dprintk("nfs_create_server: getattr error = %d\n", -error);
984 			goto error;
985 		}
986 	}
987 	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
988 
989 	dprintk("Server FSID: %llx:%llx\n",
990 		(unsigned long long) server->fsid.major,
991 		(unsigned long long) server->fsid.minor);
992 
993 	nfs_server_insert_lists(server);
994 	server->mount_time = jiffies;
995 	nfs_free_fattr(fattr);
996 	return server;
997 
998 error:
999 	nfs_free_fattr(fattr);
1000 	nfs_free_server(server);
1001 	return ERR_PTR(error);
1002 }
1003 EXPORT_SYMBOL_GPL(nfs_create_server);
1004 
1005 /*
1006  * Clone an NFS2, NFS3 or NFS4 server record
1007  */
1008 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1009 				    struct nfs_fh *fh,
1010 				    struct nfs_fattr *fattr,
1011 				    rpc_authflavor_t flavor)
1012 {
1013 	struct nfs_server *server;
1014 	struct nfs_fattr *fattr_fsinfo;
1015 	int error;
1016 
1017 	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1018 		(unsigned long long) fattr->fsid.major,
1019 		(unsigned long long) fattr->fsid.minor);
1020 
1021 	server = nfs_alloc_server();
1022 	if (!server)
1023 		return ERR_PTR(-ENOMEM);
1024 
1025 	error = -ENOMEM;
1026 	fattr_fsinfo = nfs_alloc_fattr();
1027 	if (fattr_fsinfo == NULL)
1028 		goto out_free_server;
1029 
1030 	/* Copy data from the source */
1031 	server->nfs_client = source->nfs_client;
1032 	server->destroy = source->destroy;
1033 	atomic_inc(&server->nfs_client->cl_count);
1034 	nfs_server_copy_userdata(server, source);
1035 
1036 	server->fsid = fattr->fsid;
1037 
1038 	error = nfs_init_server_rpcclient(server,
1039 			source->client->cl_timeout,
1040 			flavor);
1041 	if (error < 0)
1042 		goto out_free_server;
1043 
1044 	/* probe the filesystem info for this server filesystem */
1045 	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1046 	if (error < 0)
1047 		goto out_free_server;
1048 
1049 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1050 		server->namelen = NFS4_MAXNAMLEN;
1051 
1052 	dprintk("Cloned FSID: %llx:%llx\n",
1053 		(unsigned long long) server->fsid.major,
1054 		(unsigned long long) server->fsid.minor);
1055 
1056 	error = nfs_start_lockd(server);
1057 	if (error < 0)
1058 		goto out_free_server;
1059 
1060 	nfs_server_insert_lists(server);
1061 	server->mount_time = jiffies;
1062 
1063 	nfs_free_fattr(fattr_fsinfo);
1064 	dprintk("<-- nfs_clone_server() = %p\n", server);
1065 	return server;
1066 
1067 out_free_server:
1068 	nfs_free_fattr(fattr_fsinfo);
1069 	nfs_free_server(server);
1070 	dprintk("<-- nfs_clone_server() = error %d\n", error);
1071 	return ERR_PTR(error);
1072 }
1073 EXPORT_SYMBOL_GPL(nfs_clone_server);
1074 
1075 void nfs_clients_init(struct net *net)
1076 {
1077 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1078 
1079 	INIT_LIST_HEAD(&nn->nfs_client_list);
1080 	INIT_LIST_HEAD(&nn->nfs_volume_list);
1081 #if IS_ENABLED(CONFIG_NFS_V4)
1082 	idr_init(&nn->cb_ident_idr);
1083 #endif
1084 	spin_lock_init(&nn->nfs_client_lock);
1085 	nn->boot_time = ktime_get_real();
1086 }
1087 
1088 #ifdef CONFIG_PROC_FS
1089 static int nfs_server_list_open(struct inode *inode, struct file *file);
1090 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1091 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1092 static void nfs_server_list_stop(struct seq_file *p, void *v);
1093 static int nfs_server_list_show(struct seq_file *m, void *v);
1094 
1095 static const struct seq_operations nfs_server_list_ops = {
1096 	.start	= nfs_server_list_start,
1097 	.next	= nfs_server_list_next,
1098 	.stop	= nfs_server_list_stop,
1099 	.show	= nfs_server_list_show,
1100 };
1101 
1102 static const struct file_operations nfs_server_list_fops = {
1103 	.open		= nfs_server_list_open,
1104 	.read		= seq_read,
1105 	.llseek		= seq_lseek,
1106 	.release	= seq_release_net,
1107 };
1108 
1109 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1110 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1111 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1112 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1113 static int nfs_volume_list_show(struct seq_file *m, void *v);
1114 
1115 static const struct seq_operations nfs_volume_list_ops = {
1116 	.start	= nfs_volume_list_start,
1117 	.next	= nfs_volume_list_next,
1118 	.stop	= nfs_volume_list_stop,
1119 	.show	= nfs_volume_list_show,
1120 };
1121 
1122 static const struct file_operations nfs_volume_list_fops = {
1123 	.open		= nfs_volume_list_open,
1124 	.read		= seq_read,
1125 	.llseek		= seq_lseek,
1126 	.release	= seq_release_net,
1127 };
1128 
1129 /*
1130  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1131  * we're dealing
1132  */
1133 static int nfs_server_list_open(struct inode *inode, struct file *file)
1134 {
1135 	return seq_open_net(inode, file, &nfs_server_list_ops,
1136 			   sizeof(struct seq_net_private));
1137 }
1138 
1139 /*
1140  * set up the iterator to start reading from the server list and return the first item
1141  */
1142 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1143 				__acquires(&nn->nfs_client_lock)
1144 {
1145 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1146 
1147 	/* lock the list against modification */
1148 	spin_lock(&nn->nfs_client_lock);
1149 	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1150 }
1151 
1152 /*
1153  * move to next server
1154  */
1155 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1156 {
1157 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1158 
1159 	return seq_list_next(v, &nn->nfs_client_list, pos);
1160 }
1161 
1162 /*
1163  * clean up after reading from the transports list
1164  */
1165 static void nfs_server_list_stop(struct seq_file *p, void *v)
1166 				__releases(&nn->nfs_client_lock)
1167 {
1168 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1169 
1170 	spin_unlock(&nn->nfs_client_lock);
1171 }
1172 
1173 /*
1174  * display a header line followed by a load of call lines
1175  */
1176 static int nfs_server_list_show(struct seq_file *m, void *v)
1177 {
1178 	struct nfs_client *clp;
1179 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1180 
1181 	/* display header on line 1 */
1182 	if (v == &nn->nfs_client_list) {
1183 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1184 		return 0;
1185 	}
1186 
1187 	/* display one transport per line on subsequent lines */
1188 	clp = list_entry(v, struct nfs_client, cl_share_link);
1189 
1190 	/* Check if the client is initialized */
1191 	if (clp->cl_cons_state != NFS_CS_READY)
1192 		return 0;
1193 
1194 	rcu_read_lock();
1195 	seq_printf(m, "v%u %s %s %3d %s\n",
1196 		   clp->rpc_ops->version,
1197 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1198 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1199 		   atomic_read(&clp->cl_count),
1200 		   clp->cl_hostname);
1201 	rcu_read_unlock();
1202 
1203 	return 0;
1204 }
1205 
1206 /*
1207  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1208  */
1209 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1210 {
1211 	return seq_open_net(inode, file, &nfs_volume_list_ops,
1212 			   sizeof(struct seq_net_private));
1213 }
1214 
1215 /*
1216  * set up the iterator to start reading from the volume list and return the first item
1217  */
1218 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1219 				__acquires(&nn->nfs_client_lock)
1220 {
1221 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1222 
1223 	/* lock the list against modification */
1224 	spin_lock(&nn->nfs_client_lock);
1225 	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1226 }
1227 
1228 /*
1229  * move to next volume
1230  */
1231 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1232 {
1233 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1234 
1235 	return seq_list_next(v, &nn->nfs_volume_list, pos);
1236 }
1237 
1238 /*
1239  * clean up after reading from the transports list
1240  */
1241 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1242 				__releases(&nn->nfs_client_lock)
1243 {
1244 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1245 
1246 	spin_unlock(&nn->nfs_client_lock);
1247 }
1248 
1249 /*
1250  * display a header line followed by a load of call lines
1251  */
1252 static int nfs_volume_list_show(struct seq_file *m, void *v)
1253 {
1254 	struct nfs_server *server;
1255 	struct nfs_client *clp;
1256 	char dev[13];	// 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1257 	char fsid[34];	// 2 * 16 for %llx, 1 for ':', 1 for '\0'
1258 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1259 
1260 	/* display header on line 1 */
1261 	if (v == &nn->nfs_volume_list) {
1262 		seq_puts(m, "NV SERVER   PORT DEV          FSID"
1263 			    "                              FSC\n");
1264 		return 0;
1265 	}
1266 	/* display one transport per line on subsequent lines */
1267 	server = list_entry(v, struct nfs_server, master_link);
1268 	clp = server->nfs_client;
1269 
1270 	snprintf(dev, sizeof(dev), "%u:%u",
1271 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1272 
1273 	snprintf(fsid, sizeof(fsid), "%llx:%llx",
1274 		 (unsigned long long) server->fsid.major,
1275 		 (unsigned long long) server->fsid.minor);
1276 
1277 	rcu_read_lock();
1278 	seq_printf(m, "v%u %s %s %-12s %-33s %s\n",
1279 		   clp->rpc_ops->version,
1280 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1281 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1282 		   dev,
1283 		   fsid,
1284 		   nfs_server_fscache_state(server));
1285 	rcu_read_unlock();
1286 
1287 	return 0;
1288 }
1289 
1290 int nfs_fs_proc_net_init(struct net *net)
1291 {
1292 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1293 	struct proc_dir_entry *p;
1294 
1295 	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1296 	if (!nn->proc_nfsfs)
1297 		goto error_0;
1298 
1299 	/* a file of servers with which we're dealing */
1300 	p = proc_create("servers", S_IFREG|S_IRUGO,
1301 			nn->proc_nfsfs, &nfs_server_list_fops);
1302 	if (!p)
1303 		goto error_1;
1304 
1305 	/* a file of volumes that we have mounted */
1306 	p = proc_create("volumes", S_IFREG|S_IRUGO,
1307 			nn->proc_nfsfs, &nfs_volume_list_fops);
1308 	if (!p)
1309 		goto error_1;
1310 	return 0;
1311 
1312 error_1:
1313 	remove_proc_subtree("nfsfs", net->proc_net);
1314 error_0:
1315 	return -ENOMEM;
1316 }
1317 
1318 void nfs_fs_proc_net_exit(struct net *net)
1319 {
1320 	remove_proc_subtree("nfsfs", net->proc_net);
1321 }
1322 
1323 /*
1324  * initialise the /proc/fs/nfsfs/ directory
1325  */
1326 int __init nfs_fs_proc_init(void)
1327 {
1328 	if (!proc_mkdir("fs/nfsfs", NULL))
1329 		goto error_0;
1330 
1331 	/* a file of servers with which we're dealing */
1332 	if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1333 		goto error_1;
1334 
1335 	/* a file of volumes that we have mounted */
1336 	if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1337 		goto error_1;
1338 
1339 	return 0;
1340 error_1:
1341 	remove_proc_subtree("fs/nfsfs", NULL);
1342 error_0:
1343 	return -ENOMEM;
1344 }
1345 
1346 /*
1347  * clean up the /proc/fs/nfsfs/ directory
1348  */
1349 void nfs_fs_proc_exit(void)
1350 {
1351 	remove_proc_subtree("fs/nfsfs", NULL);
1352 }
1353 
1354 #endif /* CONFIG_PROC_FS */
1355