xref: /linux/fs/nfs/client.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
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 (IS_ERR(clp->cl_rpcclient) ||
318                             !rpc_clnt_xprt_switch_has_addr(clp->cl_rpcclient,
319 							   sap))
320 				continue;
321 
322 		atomic_inc(&clp->cl_count);
323 		return clp;
324 	}
325 	return NULL;
326 }
327 
328 /*
329  * Return true if @clp is done initializing, false if still working on it.
330  *
331  * Use nfs_client_init_status to check if it was successful.
332  */
333 bool nfs_client_init_is_complete(const struct nfs_client *clp)
334 {
335 	return clp->cl_cons_state <= NFS_CS_READY;
336 }
337 EXPORT_SYMBOL_GPL(nfs_client_init_is_complete);
338 
339 /*
340  * Return 0 if @clp was successfully initialized, -errno otherwise.
341  *
342  * This must be called *after* nfs_client_init_is_complete() returns true,
343  * otherwise it will pop WARN_ON_ONCE and return -EINVAL
344  */
345 int nfs_client_init_status(const struct nfs_client *clp)
346 {
347 	/* called without checking nfs_client_init_is_complete */
348 	if (clp->cl_cons_state > NFS_CS_READY) {
349 		WARN_ON_ONCE(1);
350 		return -EINVAL;
351 	}
352 	return clp->cl_cons_state;
353 }
354 EXPORT_SYMBOL_GPL(nfs_client_init_status);
355 
356 int nfs_wait_client_init_complete(const struct nfs_client *clp)
357 {
358 	return wait_event_killable(nfs_client_active_wq,
359 			nfs_client_init_is_complete(clp));
360 }
361 EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
362 
363 /*
364  * Found an existing client.  Make sure it's ready before returning.
365  */
366 static struct nfs_client *
367 nfs_found_client(const struct nfs_client_initdata *cl_init,
368 		 struct nfs_client *clp)
369 {
370 	int error;
371 
372 	error = nfs_wait_client_init_complete(clp);
373 	if (error < 0) {
374 		nfs_put_client(clp);
375 		return ERR_PTR(-ERESTARTSYS);
376 	}
377 
378 	if (clp->cl_cons_state < NFS_CS_READY) {
379 		error = clp->cl_cons_state;
380 		nfs_put_client(clp);
381 		return ERR_PTR(error);
382 	}
383 
384 	smp_rmb();
385 
386 	dprintk("<-- %s found nfs_client %p for %s\n",
387 		__func__, clp, cl_init->hostname ?: "");
388 	return clp;
389 }
390 
391 /*
392  * Look up a client by IP address and protocol version
393  * - creates a new record if one doesn't yet exist
394  */
395 struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
396 {
397 	struct nfs_client *clp, *new = NULL;
398 	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
399 	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
400 
401 	if (cl_init->hostname == NULL) {
402 		WARN_ON(1);
403 		return NULL;
404 	}
405 
406 	dprintk("--> nfs_get_client(%s,v%u)\n",
407 		cl_init->hostname, rpc_ops->version);
408 
409 	/* see if the client already exists */
410 	do {
411 		spin_lock(&nn->nfs_client_lock);
412 
413 		clp = nfs_match_client(cl_init);
414 		if (clp) {
415 			spin_unlock(&nn->nfs_client_lock);
416 			if (new)
417 				new->rpc_ops->free_client(new);
418 			return nfs_found_client(cl_init, clp);
419 		}
420 		if (new) {
421 			list_add_tail(&new->cl_share_link,
422 					&nn->nfs_client_list);
423 			spin_unlock(&nn->nfs_client_lock);
424 			new->cl_flags = cl_init->init_flags;
425 			return rpc_ops->init_client(new, cl_init);
426 		}
427 
428 		spin_unlock(&nn->nfs_client_lock);
429 
430 		new = rpc_ops->alloc_client(cl_init);
431 	} while (!IS_ERR(new));
432 
433 	dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
434 		cl_init->hostname, PTR_ERR(new));
435 	return new;
436 }
437 EXPORT_SYMBOL_GPL(nfs_get_client);
438 
439 /*
440  * Mark a server as ready or failed
441  */
442 void nfs_mark_client_ready(struct nfs_client *clp, int state)
443 {
444 	smp_wmb();
445 	clp->cl_cons_state = state;
446 	wake_up_all(&nfs_client_active_wq);
447 }
448 EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
449 
450 /*
451  * Initialise the timeout values for a connection
452  */
453 void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
454 				    int timeo, int retrans)
455 {
456 	to->to_initval = timeo * HZ / 10;
457 	to->to_retries = retrans;
458 
459 	switch (proto) {
460 	case XPRT_TRANSPORT_TCP:
461 	case XPRT_TRANSPORT_RDMA:
462 		if (retrans == NFS_UNSPEC_RETRANS)
463 			to->to_retries = NFS_DEF_TCP_RETRANS;
464 		if (timeo == NFS_UNSPEC_TIMEO || to->to_retries == 0)
465 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
466 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
467 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
468 		to->to_increment = to->to_initval;
469 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
470 		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
471 			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
472 		if (to->to_maxval < to->to_initval)
473 			to->to_maxval = to->to_initval;
474 		to->to_exponential = 0;
475 		break;
476 	case XPRT_TRANSPORT_UDP:
477 		if (retrans == NFS_UNSPEC_RETRANS)
478 			to->to_retries = NFS_DEF_UDP_RETRANS;
479 		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
480 			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
481 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
482 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
483 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
484 		to->to_exponential = 1;
485 		break;
486 	default:
487 		BUG();
488 	}
489 }
490 EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
491 
492 /*
493  * Create an RPC client handle
494  */
495 int nfs_create_rpc_client(struct nfs_client *clp,
496 			  const struct nfs_client_initdata *cl_init,
497 			  rpc_authflavor_t flavor)
498 {
499 	struct rpc_clnt		*clnt = NULL;
500 	struct rpc_create_args args = {
501 		.net		= clp->cl_net,
502 		.protocol	= clp->cl_proto,
503 		.address	= (struct sockaddr *)&clp->cl_addr,
504 		.addrsize	= clp->cl_addrlen,
505 		.timeout	= cl_init->timeparms,
506 		.servername	= clp->cl_hostname,
507 		.nodename	= cl_init->nodename,
508 		.program	= &nfs_program,
509 		.version	= clp->rpc_ops->version,
510 		.authflavor	= flavor,
511 	};
512 
513 	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
514 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
515 	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
516 		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
517 	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
518 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
519 	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
520 		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
521 
522 	if (!IS_ERR(clp->cl_rpcclient))
523 		return 0;
524 
525 	clnt = rpc_create(&args);
526 	if (IS_ERR(clnt)) {
527 		dprintk("%s: cannot create RPC client. Error = %ld\n",
528 				__func__, PTR_ERR(clnt));
529 		return PTR_ERR(clnt);
530 	}
531 
532 	clp->cl_rpcclient = clnt;
533 	return 0;
534 }
535 EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
536 
537 /*
538  * Version 2 or 3 client destruction
539  */
540 static void nfs_destroy_server(struct nfs_server *server)
541 {
542 	if (server->nlm_host)
543 		nlmclnt_done(server->nlm_host);
544 }
545 
546 /*
547  * Version 2 or 3 lockd setup
548  */
549 static int nfs_start_lockd(struct nfs_server *server)
550 {
551 	struct nlm_host *host;
552 	struct nfs_client *clp = server->nfs_client;
553 	struct nlmclnt_initdata nlm_init = {
554 		.hostname	= clp->cl_hostname,
555 		.address	= (struct sockaddr *)&clp->cl_addr,
556 		.addrlen	= clp->cl_addrlen,
557 		.nfs_version	= clp->rpc_ops->version,
558 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
559 					1 : 0,
560 		.net		= clp->cl_net,
561 	};
562 
563 	if (nlm_init.nfs_version > 3)
564 		return 0;
565 	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
566 			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
567 		return 0;
568 
569 	switch (clp->cl_proto) {
570 		default:
571 			nlm_init.protocol = IPPROTO_TCP;
572 			break;
573 		case XPRT_TRANSPORT_UDP:
574 			nlm_init.protocol = IPPROTO_UDP;
575 	}
576 
577 	host = nlmclnt_init(&nlm_init);
578 	if (IS_ERR(host))
579 		return PTR_ERR(host);
580 
581 	server->nlm_host = host;
582 	server->destroy = nfs_destroy_server;
583 	return 0;
584 }
585 
586 /*
587  * Create a general RPC client
588  */
589 int nfs_init_server_rpcclient(struct nfs_server *server,
590 		const struct rpc_timeout *timeo,
591 		rpc_authflavor_t pseudoflavour)
592 {
593 	struct nfs_client *clp = server->nfs_client;
594 
595 	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
596 							pseudoflavour);
597 	if (IS_ERR(server->client)) {
598 		dprintk("%s: couldn't create rpc_client!\n", __func__);
599 		return PTR_ERR(server->client);
600 	}
601 
602 	memcpy(&server->client->cl_timeout_default,
603 			timeo,
604 			sizeof(server->client->cl_timeout_default));
605 	server->client->cl_timeout = &server->client->cl_timeout_default;
606 	server->client->cl_softrtry = 0;
607 	if (server->flags & NFS_MOUNT_SOFT)
608 		server->client->cl_softrtry = 1;
609 
610 	return 0;
611 }
612 EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
613 
614 /**
615  * nfs_init_client - Initialise an NFS2 or NFS3 client
616  *
617  * @clp: nfs_client to initialise
618  * @cl_init: Initialisation parameters
619  *
620  * Returns pointer to an NFS client, or an ERR_PTR value.
621  */
622 struct nfs_client *nfs_init_client(struct nfs_client *clp,
623 				   const struct nfs_client_initdata *cl_init)
624 {
625 	int error;
626 
627 	if (clp->cl_cons_state == NFS_CS_READY) {
628 		/* the client is already initialised */
629 		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
630 		return clp;
631 	}
632 
633 	/*
634 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
635 	 * - RFC 2623, sec 2.3.2
636 	 */
637 	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
638 	if (error < 0)
639 		goto error;
640 	nfs_mark_client_ready(clp, NFS_CS_READY);
641 	return clp;
642 
643 error:
644 	nfs_mark_client_ready(clp, error);
645 	nfs_put_client(clp);
646 	dprintk("<-- nfs_init_client() = xerror %d\n", error);
647 	return ERR_PTR(error);
648 }
649 EXPORT_SYMBOL_GPL(nfs_init_client);
650 
651 /*
652  * Create a version 2 or 3 client
653  */
654 static int nfs_init_server(struct nfs_server *server,
655 			   const struct nfs_parsed_mount_data *data,
656 			   struct nfs_subversion *nfs_mod)
657 {
658 	struct rpc_timeout timeparms;
659 	struct nfs_client_initdata cl_init = {
660 		.hostname = data->nfs_server.hostname,
661 		.addr = (const struct sockaddr *)&data->nfs_server.address,
662 		.addrlen = data->nfs_server.addrlen,
663 		.nfs_mod = nfs_mod,
664 		.proto = data->nfs_server.protocol,
665 		.net = data->net,
666 		.timeparms = &timeparms,
667 	};
668 	struct nfs_client *clp;
669 	int error;
670 
671 	dprintk("--> nfs_init_server()\n");
672 
673 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
674 			data->timeo, data->retrans);
675 	if (data->flags & NFS_MOUNT_NORESVPORT)
676 		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
677 
678 	/* Allocate or find a client reference we can use */
679 	clp = nfs_get_client(&cl_init);
680 	if (IS_ERR(clp)) {
681 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
682 		return PTR_ERR(clp);
683 	}
684 
685 	server->nfs_client = clp;
686 
687 	/* Initialise the client representation from the mount data */
688 	server->flags = data->flags;
689 	server->options = data->options;
690 	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
691 		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
692 		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
693 
694 	if (data->rsize)
695 		server->rsize = nfs_block_size(data->rsize, NULL);
696 	if (data->wsize)
697 		server->wsize = nfs_block_size(data->wsize, NULL);
698 
699 	server->acregmin = data->acregmin * HZ;
700 	server->acregmax = data->acregmax * HZ;
701 	server->acdirmin = data->acdirmin * HZ;
702 	server->acdirmax = data->acdirmax * HZ;
703 
704 	/* Start lockd here, before we might error out */
705 	error = nfs_start_lockd(server);
706 	if (error < 0)
707 		goto error;
708 
709 	server->port = data->nfs_server.port;
710 	server->auth_info = data->auth_info;
711 
712 	error = nfs_init_server_rpcclient(server, &timeparms,
713 					  data->selected_flavor);
714 	if (error < 0)
715 		goto error;
716 
717 	/* Preserve the values of mount_server-related mount options */
718 	if (data->mount_server.addrlen) {
719 		memcpy(&server->mountd_address, &data->mount_server.address,
720 			data->mount_server.addrlen);
721 		server->mountd_addrlen = data->mount_server.addrlen;
722 	}
723 	server->mountd_version = data->mount_server.version;
724 	server->mountd_port = data->mount_server.port;
725 	server->mountd_protocol = data->mount_server.protocol;
726 
727 	server->namelen  = data->namlen;
728 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
729 	return 0;
730 
731 error:
732 	server->nfs_client = NULL;
733 	nfs_put_client(clp);
734 	dprintk("<-- nfs_init_server() = xerror %d\n", error);
735 	return error;
736 }
737 
738 /*
739  * Load up the server record from information gained in an fsinfo record
740  */
741 static void nfs_server_set_fsinfo(struct nfs_server *server,
742 				  struct nfs_fsinfo *fsinfo)
743 {
744 	unsigned long max_rpc_payload;
745 
746 	/* Work out a lot of parameters */
747 	if (server->rsize == 0)
748 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
749 	if (server->wsize == 0)
750 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
751 
752 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
753 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
754 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
755 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
756 
757 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
758 	if (server->rsize > max_rpc_payload)
759 		server->rsize = max_rpc_payload;
760 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
761 		server->rsize = NFS_MAX_FILE_IO_SIZE;
762 	server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
763 
764 	server->backing_dev_info.name = "nfs";
765 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
766 
767 	if (server->wsize > max_rpc_payload)
768 		server->wsize = max_rpc_payload;
769 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
770 		server->wsize = NFS_MAX_FILE_IO_SIZE;
771 	server->wpages = (server->wsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
772 
773 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
774 
775 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
776 	if (server->dtsize > PAGE_SIZE * NFS_MAX_READDIR_PAGES)
777 		server->dtsize = PAGE_SIZE * NFS_MAX_READDIR_PAGES;
778 	if (server->dtsize > server->rsize)
779 		server->dtsize = server->rsize;
780 
781 	if (server->flags & NFS_MOUNT_NOAC) {
782 		server->acregmin = server->acregmax = 0;
783 		server->acdirmin = server->acdirmax = 0;
784 	}
785 
786 	server->maxfilesize = fsinfo->maxfilesize;
787 
788 	server->time_delta = fsinfo->time_delta;
789 
790 	server->clone_blksize = fsinfo->clone_blksize;
791 	/* We're airborne Set socket buffersize */
792 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
793 }
794 
795 /*
796  * Probe filesystem information, including the FSID on v2/v3
797  */
798 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
799 {
800 	struct nfs_fsinfo fsinfo;
801 	struct nfs_client *clp = server->nfs_client;
802 	int error;
803 
804 	dprintk("--> nfs_probe_fsinfo()\n");
805 
806 	if (clp->rpc_ops->set_capabilities != NULL) {
807 		error = clp->rpc_ops->set_capabilities(server, mntfh);
808 		if (error < 0)
809 			goto out_error;
810 	}
811 
812 	fsinfo.fattr = fattr;
813 	fsinfo.nlayouttypes = 0;
814 	memset(fsinfo.layouttype, 0, sizeof(fsinfo.layouttype));
815 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
816 	if (error < 0)
817 		goto out_error;
818 
819 	nfs_server_set_fsinfo(server, &fsinfo);
820 
821 	/* Get some general file system info */
822 	if (server->namelen == 0) {
823 		struct nfs_pathconf pathinfo;
824 
825 		pathinfo.fattr = fattr;
826 		nfs_fattr_init(fattr);
827 
828 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
829 			server->namelen = pathinfo.max_namelen;
830 	}
831 
832 	dprintk("<-- nfs_probe_fsinfo() = 0\n");
833 	return 0;
834 
835 out_error:
836 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
837 	return error;
838 }
839 EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
840 
841 /*
842  * Copy useful information when duplicating a server record
843  */
844 void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
845 {
846 	target->flags = source->flags;
847 	target->rsize = source->rsize;
848 	target->wsize = source->wsize;
849 	target->acregmin = source->acregmin;
850 	target->acregmax = source->acregmax;
851 	target->acdirmin = source->acdirmin;
852 	target->acdirmax = source->acdirmax;
853 	target->caps = source->caps;
854 	target->options = source->options;
855 	target->auth_info = source->auth_info;
856 }
857 EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
858 
859 void nfs_server_insert_lists(struct nfs_server *server)
860 {
861 	struct nfs_client *clp = server->nfs_client;
862 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
863 
864 	spin_lock(&nn->nfs_client_lock);
865 	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
866 	list_add_tail(&server->master_link, &nn->nfs_volume_list);
867 	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
868 	spin_unlock(&nn->nfs_client_lock);
869 
870 }
871 EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
872 
873 void nfs_server_remove_lists(struct nfs_server *server)
874 {
875 	struct nfs_client *clp = server->nfs_client;
876 	struct nfs_net *nn;
877 
878 	if (clp == NULL)
879 		return;
880 	nn = net_generic(clp->cl_net, nfs_net_id);
881 	spin_lock(&nn->nfs_client_lock);
882 	list_del_rcu(&server->client_link);
883 	if (list_empty(&clp->cl_superblocks))
884 		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
885 	list_del(&server->master_link);
886 	spin_unlock(&nn->nfs_client_lock);
887 
888 	synchronize_rcu();
889 }
890 EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
891 
892 /*
893  * Allocate and initialise a server record
894  */
895 struct nfs_server *nfs_alloc_server(void)
896 {
897 	struct nfs_server *server;
898 
899 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
900 	if (!server)
901 		return NULL;
902 
903 	server->client = server->client_acl = ERR_PTR(-EINVAL);
904 
905 	/* Zero out the NFS state stuff */
906 	INIT_LIST_HEAD(&server->client_link);
907 	INIT_LIST_HEAD(&server->master_link);
908 	INIT_LIST_HEAD(&server->delegations);
909 	INIT_LIST_HEAD(&server->layouts);
910 	INIT_LIST_HEAD(&server->state_owners_lru);
911 
912 	atomic_set(&server->active, 0);
913 
914 	server->io_stats = nfs_alloc_iostats();
915 	if (!server->io_stats) {
916 		kfree(server);
917 		return NULL;
918 	}
919 
920 	if (bdi_init(&server->backing_dev_info)) {
921 		nfs_free_iostats(server->io_stats);
922 		kfree(server);
923 		return NULL;
924 	}
925 
926 	ida_init(&server->openowner_id);
927 	ida_init(&server->lockowner_id);
928 	pnfs_init_server(server);
929 
930 	return server;
931 }
932 EXPORT_SYMBOL_GPL(nfs_alloc_server);
933 
934 /*
935  * Free up a server record
936  */
937 void nfs_free_server(struct nfs_server *server)
938 {
939 	dprintk("--> nfs_free_server()\n");
940 
941 	nfs_server_remove_lists(server);
942 
943 	if (server->destroy != NULL)
944 		server->destroy(server);
945 
946 	if (!IS_ERR(server->client_acl))
947 		rpc_shutdown_client(server->client_acl);
948 	if (!IS_ERR(server->client))
949 		rpc_shutdown_client(server->client);
950 
951 	nfs_put_client(server->nfs_client);
952 
953 	ida_destroy(&server->lockowner_id);
954 	ida_destroy(&server->openowner_id);
955 	nfs_free_iostats(server->io_stats);
956 	bdi_destroy(&server->backing_dev_info);
957 	kfree(server);
958 	nfs_release_automount_timer();
959 	dprintk("<-- nfs_free_server()\n");
960 }
961 EXPORT_SYMBOL_GPL(nfs_free_server);
962 
963 /*
964  * Create a version 2 or 3 volume record
965  * - keyed on server and FSID
966  */
967 struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
968 				     struct nfs_subversion *nfs_mod)
969 {
970 	struct nfs_server *server;
971 	struct nfs_fattr *fattr;
972 	int error;
973 
974 	server = nfs_alloc_server();
975 	if (!server)
976 		return ERR_PTR(-ENOMEM);
977 
978 	error = -ENOMEM;
979 	fattr = nfs_alloc_fattr();
980 	if (fattr == NULL)
981 		goto error;
982 
983 	/* Get a client representation */
984 	error = nfs_init_server(server, mount_info->parsed, nfs_mod);
985 	if (error < 0)
986 		goto error;
987 
988 	/* Probe the root fh to retrieve its FSID */
989 	error = nfs_probe_fsinfo(server, mount_info->mntfh, fattr);
990 	if (error < 0)
991 		goto error;
992 	if (server->nfs_client->rpc_ops->version == 3) {
993 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
994 			server->namelen = NFS3_MAXNAMLEN;
995 		if (!(mount_info->parsed->flags & NFS_MOUNT_NORDIRPLUS))
996 			server->caps |= NFS_CAP_READDIRPLUS;
997 	} else {
998 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
999 			server->namelen = NFS2_MAXNAMLEN;
1000 	}
1001 
1002 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
1003 		error = nfs_mod->rpc_ops->getattr(server, mount_info->mntfh, fattr, NULL);
1004 		if (error < 0) {
1005 			dprintk("nfs_create_server: getattr error = %d\n", -error);
1006 			goto error;
1007 		}
1008 	}
1009 	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1010 
1011 	dprintk("Server FSID: %llx:%llx\n",
1012 		(unsigned long long) server->fsid.major,
1013 		(unsigned long long) server->fsid.minor);
1014 
1015 	nfs_server_insert_lists(server);
1016 	server->mount_time = jiffies;
1017 	nfs_free_fattr(fattr);
1018 	return server;
1019 
1020 error:
1021 	nfs_free_fattr(fattr);
1022 	nfs_free_server(server);
1023 	return ERR_PTR(error);
1024 }
1025 EXPORT_SYMBOL_GPL(nfs_create_server);
1026 
1027 /*
1028  * Clone an NFS2, NFS3 or NFS4 server record
1029  */
1030 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1031 				    struct nfs_fh *fh,
1032 				    struct nfs_fattr *fattr,
1033 				    rpc_authflavor_t flavor)
1034 {
1035 	struct nfs_server *server;
1036 	struct nfs_fattr *fattr_fsinfo;
1037 	int error;
1038 
1039 	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1040 		(unsigned long long) fattr->fsid.major,
1041 		(unsigned long long) fattr->fsid.minor);
1042 
1043 	server = nfs_alloc_server();
1044 	if (!server)
1045 		return ERR_PTR(-ENOMEM);
1046 
1047 	error = -ENOMEM;
1048 	fattr_fsinfo = nfs_alloc_fattr();
1049 	if (fattr_fsinfo == NULL)
1050 		goto out_free_server;
1051 
1052 	/* Copy data from the source */
1053 	server->nfs_client = source->nfs_client;
1054 	server->destroy = source->destroy;
1055 	atomic_inc(&server->nfs_client->cl_count);
1056 	nfs_server_copy_userdata(server, source);
1057 
1058 	server->fsid = fattr->fsid;
1059 
1060 	error = nfs_init_server_rpcclient(server,
1061 			source->client->cl_timeout,
1062 			flavor);
1063 	if (error < 0)
1064 		goto out_free_server;
1065 
1066 	/* probe the filesystem info for this server filesystem */
1067 	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1068 	if (error < 0)
1069 		goto out_free_server;
1070 
1071 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1072 		server->namelen = NFS4_MAXNAMLEN;
1073 
1074 	dprintk("Cloned FSID: %llx:%llx\n",
1075 		(unsigned long long) server->fsid.major,
1076 		(unsigned long long) server->fsid.minor);
1077 
1078 	error = nfs_start_lockd(server);
1079 	if (error < 0)
1080 		goto out_free_server;
1081 
1082 	nfs_server_insert_lists(server);
1083 	server->mount_time = jiffies;
1084 
1085 	nfs_free_fattr(fattr_fsinfo);
1086 	dprintk("<-- nfs_clone_server() = %p\n", server);
1087 	return server;
1088 
1089 out_free_server:
1090 	nfs_free_fattr(fattr_fsinfo);
1091 	nfs_free_server(server);
1092 	dprintk("<-- nfs_clone_server() = error %d\n", error);
1093 	return ERR_PTR(error);
1094 }
1095 EXPORT_SYMBOL_GPL(nfs_clone_server);
1096 
1097 void nfs_clients_init(struct net *net)
1098 {
1099 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1100 
1101 	INIT_LIST_HEAD(&nn->nfs_client_list);
1102 	INIT_LIST_HEAD(&nn->nfs_volume_list);
1103 #if IS_ENABLED(CONFIG_NFS_V4)
1104 	idr_init(&nn->cb_ident_idr);
1105 #endif
1106 	spin_lock_init(&nn->nfs_client_lock);
1107 	nn->boot_time = ktime_get_real();
1108 }
1109 
1110 #ifdef CONFIG_PROC_FS
1111 static int nfs_server_list_open(struct inode *inode, struct file *file);
1112 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1113 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1114 static void nfs_server_list_stop(struct seq_file *p, void *v);
1115 static int nfs_server_list_show(struct seq_file *m, void *v);
1116 
1117 static const struct seq_operations nfs_server_list_ops = {
1118 	.start	= nfs_server_list_start,
1119 	.next	= nfs_server_list_next,
1120 	.stop	= nfs_server_list_stop,
1121 	.show	= nfs_server_list_show,
1122 };
1123 
1124 static const struct file_operations nfs_server_list_fops = {
1125 	.open		= nfs_server_list_open,
1126 	.read		= seq_read,
1127 	.llseek		= seq_lseek,
1128 	.release	= seq_release_net,
1129 };
1130 
1131 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1132 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1133 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1134 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1135 static int nfs_volume_list_show(struct seq_file *m, void *v);
1136 
1137 static const struct seq_operations nfs_volume_list_ops = {
1138 	.start	= nfs_volume_list_start,
1139 	.next	= nfs_volume_list_next,
1140 	.stop	= nfs_volume_list_stop,
1141 	.show	= nfs_volume_list_show,
1142 };
1143 
1144 static const struct file_operations nfs_volume_list_fops = {
1145 	.open		= nfs_volume_list_open,
1146 	.read		= seq_read,
1147 	.llseek		= seq_lseek,
1148 	.release	= seq_release_net,
1149 };
1150 
1151 /*
1152  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1153  * we're dealing
1154  */
1155 static int nfs_server_list_open(struct inode *inode, struct file *file)
1156 {
1157 	return seq_open_net(inode, file, &nfs_server_list_ops,
1158 			   sizeof(struct seq_net_private));
1159 }
1160 
1161 /*
1162  * set up the iterator to start reading from the server list and return the first item
1163  */
1164 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1165 				__acquires(&nn->nfs_client_lock)
1166 {
1167 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1168 
1169 	/* lock the list against modification */
1170 	spin_lock(&nn->nfs_client_lock);
1171 	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1172 }
1173 
1174 /*
1175  * move to next server
1176  */
1177 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1178 {
1179 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1180 
1181 	return seq_list_next(v, &nn->nfs_client_list, pos);
1182 }
1183 
1184 /*
1185  * clean up after reading from the transports list
1186  */
1187 static void nfs_server_list_stop(struct seq_file *p, void *v)
1188 				__releases(&nn->nfs_client_lock)
1189 {
1190 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1191 
1192 	spin_unlock(&nn->nfs_client_lock);
1193 }
1194 
1195 /*
1196  * display a header line followed by a load of call lines
1197  */
1198 static int nfs_server_list_show(struct seq_file *m, void *v)
1199 {
1200 	struct nfs_client *clp;
1201 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1202 
1203 	/* display header on line 1 */
1204 	if (v == &nn->nfs_client_list) {
1205 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1206 		return 0;
1207 	}
1208 
1209 	/* display one transport per line on subsequent lines */
1210 	clp = list_entry(v, struct nfs_client, cl_share_link);
1211 
1212 	/* Check if the client is initialized */
1213 	if (clp->cl_cons_state != NFS_CS_READY)
1214 		return 0;
1215 
1216 	rcu_read_lock();
1217 	seq_printf(m, "v%u %s %s %3d %s\n",
1218 		   clp->rpc_ops->version,
1219 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1220 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1221 		   atomic_read(&clp->cl_count),
1222 		   clp->cl_hostname);
1223 	rcu_read_unlock();
1224 
1225 	return 0;
1226 }
1227 
1228 /*
1229  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1230  */
1231 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1232 {
1233 	return seq_open_net(inode, file, &nfs_volume_list_ops,
1234 			   sizeof(struct seq_net_private));
1235 }
1236 
1237 /*
1238  * set up the iterator to start reading from the volume list and return the first item
1239  */
1240 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1241 				__acquires(&nn->nfs_client_lock)
1242 {
1243 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1244 
1245 	/* lock the list against modification */
1246 	spin_lock(&nn->nfs_client_lock);
1247 	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1248 }
1249 
1250 /*
1251  * move to next volume
1252  */
1253 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1254 {
1255 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1256 
1257 	return seq_list_next(v, &nn->nfs_volume_list, pos);
1258 }
1259 
1260 /*
1261  * clean up after reading from the transports list
1262  */
1263 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1264 				__releases(&nn->nfs_client_lock)
1265 {
1266 	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1267 
1268 	spin_unlock(&nn->nfs_client_lock);
1269 }
1270 
1271 /*
1272  * display a header line followed by a load of call lines
1273  */
1274 static int nfs_volume_list_show(struct seq_file *m, void *v)
1275 {
1276 	struct nfs_server *server;
1277 	struct nfs_client *clp;
1278 	char dev[13];	// 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1279 	char fsid[34];	// 2 * 16 for %llx, 1 for ':', 1 for '\0'
1280 	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1281 
1282 	/* display header on line 1 */
1283 	if (v == &nn->nfs_volume_list) {
1284 		seq_puts(m, "NV SERVER   PORT DEV          FSID"
1285 			    "                              FSC\n");
1286 		return 0;
1287 	}
1288 	/* display one transport per line on subsequent lines */
1289 	server = list_entry(v, struct nfs_server, master_link);
1290 	clp = server->nfs_client;
1291 
1292 	snprintf(dev, sizeof(dev), "%u:%u",
1293 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1294 
1295 	snprintf(fsid, sizeof(fsid), "%llx:%llx",
1296 		 (unsigned long long) server->fsid.major,
1297 		 (unsigned long long) server->fsid.minor);
1298 
1299 	rcu_read_lock();
1300 	seq_printf(m, "v%u %s %s %-12s %-33s %s\n",
1301 		   clp->rpc_ops->version,
1302 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1303 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1304 		   dev,
1305 		   fsid,
1306 		   nfs_server_fscache_state(server));
1307 	rcu_read_unlock();
1308 
1309 	return 0;
1310 }
1311 
1312 int nfs_fs_proc_net_init(struct net *net)
1313 {
1314 	struct nfs_net *nn = net_generic(net, nfs_net_id);
1315 	struct proc_dir_entry *p;
1316 
1317 	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1318 	if (!nn->proc_nfsfs)
1319 		goto error_0;
1320 
1321 	/* a file of servers with which we're dealing */
1322 	p = proc_create("servers", S_IFREG|S_IRUGO,
1323 			nn->proc_nfsfs, &nfs_server_list_fops);
1324 	if (!p)
1325 		goto error_1;
1326 
1327 	/* a file of volumes that we have mounted */
1328 	p = proc_create("volumes", S_IFREG|S_IRUGO,
1329 			nn->proc_nfsfs, &nfs_volume_list_fops);
1330 	if (!p)
1331 		goto error_1;
1332 	return 0;
1333 
1334 error_1:
1335 	remove_proc_subtree("nfsfs", net->proc_net);
1336 error_0:
1337 	return -ENOMEM;
1338 }
1339 
1340 void nfs_fs_proc_net_exit(struct net *net)
1341 {
1342 	remove_proc_subtree("nfsfs", net->proc_net);
1343 }
1344 
1345 /*
1346  * initialise the /proc/fs/nfsfs/ directory
1347  */
1348 int __init nfs_fs_proc_init(void)
1349 {
1350 	if (!proc_mkdir("fs/nfsfs", NULL))
1351 		goto error_0;
1352 
1353 	/* a file of servers with which we're dealing */
1354 	if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1355 		goto error_1;
1356 
1357 	/* a file of volumes that we have mounted */
1358 	if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1359 		goto error_1;
1360 
1361 	return 0;
1362 error_1:
1363 	remove_proc_subtree("fs/nfsfs", NULL);
1364 error_0:
1365 	return -ENOMEM;
1366 }
1367 
1368 /*
1369  * clean up the /proc/fs/nfsfs/ directory
1370  */
1371 void nfs_fs_proc_exit(void)
1372 {
1373 	remove_proc_subtree("fs/nfsfs", NULL);
1374 }
1375 
1376 #endif /* CONFIG_PROC_FS */
1377