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/clnt.h>
24#include <linux/sunrpc/stats.h>
25#include <linux/sunrpc/metrics.h>
26#include <linux/sunrpc/xprtsock.h>
27#include <linux/sunrpc/xprtrdma.h>
28#include <linux/nfs_fs.h>
29#include <linux/nfs_mount.h>
30#include <linux/nfs4_mount.h>
31#include <linux/lockd/bind.h>
32#include <linux/seq_file.h>
33#include <linux/mount.h>
34#include <linux/vfs.h>
35#include <linux/inet.h>
36#include <linux/in6.h>
37#include <linux/slab.h>
38#include <linux/idr.h>
39#include <net/ipv6.h>
40#include <linux/nfs_xdr.h>
41#include <linux/sunrpc/bc_xprt.h>
42#include <linux/nsproxy.h>
43#include <linux/pid_namespace.h>
44
45
46#include "nfs4_fs.h"
47#include "callback.h"
48#include "delegation.h"
49#include "iostat.h"
50#include "internal.h"
51#include "fscache.h"
52#include "pnfs.h"
53#include "nfs.h"
54#include "netns.h"
55
56#define NFSDBG_FACILITY		NFSDBG_CLIENT
57
58static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
59static DEFINE_SPINLOCK(nfs_version_lock);
60static DEFINE_MUTEX(nfs_version_mutex);
61static LIST_HEAD(nfs_versions);
62
63/*
64 * RPC cruft for NFS
65 */
66static const struct rpc_version *nfs_version[5] = {
67	[2] = NULL,
68	[3] = NULL,
69	[4] = NULL,
70};
71
72const struct rpc_program nfs_program = {
73	.name			= "nfs",
74	.number			= NFS_PROGRAM,
75	.nrvers			= ARRAY_SIZE(nfs_version),
76	.version		= nfs_version,
77	.stats			= &nfs_rpcstat,
78	.pipe_dir_name		= NFS_PIPE_DIRNAME,
79};
80
81struct rpc_stat nfs_rpcstat = {
82	.program		= &nfs_program
83};
84
85static struct nfs_subversion *find_nfs_version(unsigned int version)
86{
87	struct nfs_subversion *nfs;
88	spin_lock(&nfs_version_lock);
89
90	list_for_each_entry(nfs, &nfs_versions, list) {
91		if (nfs->rpc_ops->version == version) {
92			spin_unlock(&nfs_version_lock);
93			return nfs;
94		}
95	}
96
97	spin_unlock(&nfs_version_lock);
98	return ERR_PTR(-EPROTONOSUPPORT);
99}
100
101struct nfs_subversion *get_nfs_version(unsigned int version)
102{
103	struct nfs_subversion *nfs = find_nfs_version(version);
104
105	if (IS_ERR(nfs)) {
106		mutex_lock(&nfs_version_mutex);
107		request_module("nfsv%d", version);
108		nfs = find_nfs_version(version);
109		mutex_unlock(&nfs_version_mutex);
110	}
111
112	if (!IS_ERR(nfs) && !try_module_get(nfs->owner))
113		return ERR_PTR(-EAGAIN);
114	return nfs;
115}
116
117void put_nfs_version(struct nfs_subversion *nfs)
118{
119	module_put(nfs->owner);
120}
121
122void register_nfs_version(struct nfs_subversion *nfs)
123{
124	spin_lock(&nfs_version_lock);
125
126	list_add(&nfs->list, &nfs_versions);
127	nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
128
129	spin_unlock(&nfs_version_lock);
130}
131EXPORT_SYMBOL_GPL(register_nfs_version);
132
133void unregister_nfs_version(struct nfs_subversion *nfs)
134{
135	spin_lock(&nfs_version_lock);
136
137	nfs_version[nfs->rpc_ops->version] = NULL;
138	list_del(&nfs->list);
139
140	spin_unlock(&nfs_version_lock);
141}
142EXPORT_SYMBOL_GPL(unregister_nfs_version);
143
144/*
145 * Allocate a shared client record
146 *
147 * Since these are allocated/deallocated very rarely, we don't
148 * bother putting them in a slab cache...
149 */
150struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
151{
152	struct nfs_client *clp;
153	struct rpc_cred *cred;
154	int err = -ENOMEM;
155
156	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
157		goto error_0;
158
159	clp->cl_nfs_mod = cl_init->nfs_mod;
160	if (!try_module_get(clp->cl_nfs_mod->owner))
161		goto error_dealloc;
162
163	clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
164
165	atomic_set(&clp->cl_count, 1);
166	clp->cl_cons_state = NFS_CS_INITING;
167
168	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
169	clp->cl_addrlen = cl_init->addrlen;
170
171	if (cl_init->hostname) {
172		err = -ENOMEM;
173		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
174		if (!clp->cl_hostname)
175			goto error_cleanup;
176	}
177
178	INIT_LIST_HEAD(&clp->cl_superblocks);
179	clp->cl_rpcclient = ERR_PTR(-EINVAL);
180
181	clp->cl_proto = cl_init->proto;
182	clp->cl_net = get_net(cl_init->net);
183
184	cred = rpc_lookup_machine_cred("*");
185	if (!IS_ERR(cred))
186		clp->cl_machine_cred = cred;
187	nfs_fscache_get_client_cookie(clp);
188
189	return clp;
190
191error_cleanup:
192	put_nfs_version(clp->cl_nfs_mod);
193error_dealloc:
194	kfree(clp);
195error_0:
196	return ERR_PTR(err);
197}
198EXPORT_SYMBOL_GPL(nfs_alloc_client);
199
200#if IS_ENABLED(CONFIG_NFS_V4)
201void nfs_cleanup_cb_ident_idr(struct net *net)
202{
203	struct nfs_net *nn = net_generic(net, nfs_net_id);
204
205	idr_destroy(&nn->cb_ident_idr);
206}
207
208/* nfs_client_lock held */
209static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
210{
211	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
212
213	if (clp->cl_cb_ident)
214		idr_remove(&nn->cb_ident_idr, clp->cl_cb_ident);
215}
216
217static void pnfs_init_server(struct nfs_server *server)
218{
219	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
220}
221
222#else
223void nfs_cleanup_cb_ident_idr(struct net *net)
224{
225}
226
227static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
228{
229}
230
231static void pnfs_init_server(struct nfs_server *server)
232{
233}
234
235#endif /* CONFIG_NFS_V4 */
236
237/*
238 * Destroy a shared client record
239 */
240void nfs_free_client(struct nfs_client *clp)
241{
242	dprintk("--> nfs_free_client(%u)\n", clp->rpc_ops->version);
243
244	nfs_fscache_release_client_cookie(clp);
245
246	/* -EIO all pending I/O */
247	if (!IS_ERR(clp->cl_rpcclient))
248		rpc_shutdown_client(clp->cl_rpcclient);
249
250	if (clp->cl_machine_cred != NULL)
251		put_rpccred(clp->cl_machine_cred);
252
253	put_net(clp->cl_net);
254	put_nfs_version(clp->cl_nfs_mod);
255	kfree(clp->cl_hostname);
256	kfree(clp->cl_acceptor);
257	kfree(clp);
258
259	dprintk("<-- nfs_free_client()\n");
260}
261EXPORT_SYMBOL_GPL(nfs_free_client);
262
263/*
264 * Release a reference to a shared client record
265 */
266void nfs_put_client(struct nfs_client *clp)
267{
268	struct nfs_net *nn;
269
270	if (!clp)
271		return;
272
273	dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
274	nn = net_generic(clp->cl_net, nfs_net_id);
275
276	if (atomic_dec_and_lock(&clp->cl_count, &nn->nfs_client_lock)) {
277		list_del(&clp->cl_share_link);
278		nfs_cb_idr_remove_locked(clp);
279		spin_unlock(&nn->nfs_client_lock);
280
281		WARN_ON_ONCE(!list_empty(&clp->cl_superblocks));
282
283		clp->rpc_ops->free_client(clp);
284	}
285}
286EXPORT_SYMBOL_GPL(nfs_put_client);
287
288#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
289/*
290 * Test if two ip6 socket addresses refer to the same socket by
291 * comparing relevant fields. The padding bytes specifically, are not
292 * compared. sin6_flowinfo is not compared because it only affects QoS
293 * and sin6_scope_id is only compared if the address is "link local"
294 * because "link local" addresses need only be unique to a specific
295 * link. Conversely, ordinary unicast addresses might have different
296 * sin6_scope_id.
297 *
298 * The caller should ensure both socket addresses are AF_INET6.
299 */
300static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
301				      const struct sockaddr *sa2)
302{
303	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
304	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
305
306	if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
307		return 0;
308	else if (ipv6_addr_type(&sin1->sin6_addr) & IPV6_ADDR_LINKLOCAL)
309		return sin1->sin6_scope_id == sin2->sin6_scope_id;
310
311	return 1;
312}
313#else	/* !defined(CONFIG_IPV6) && !defined(CONFIG_IPV6_MODULE) */
314static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
315				      const struct sockaddr *sa2)
316{
317	return 0;
318}
319#endif
320
321/*
322 * Test if two ip4 socket addresses refer to the same socket, by
323 * comparing relevant fields. The padding bytes specifically, are
324 * not compared.
325 *
326 * The caller should ensure both socket addresses are AF_INET.
327 */
328static int nfs_sockaddr_match_ipaddr4(const struct sockaddr *sa1,
329				      const struct sockaddr *sa2)
330{
331	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
332	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
333
334	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
335}
336
337static int nfs_sockaddr_cmp_ip6(const struct sockaddr *sa1,
338				const struct sockaddr *sa2)
339{
340	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
341	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
342
343	return nfs_sockaddr_match_ipaddr6(sa1, sa2) &&
344		(sin1->sin6_port == sin2->sin6_port);
345}
346
347static int nfs_sockaddr_cmp_ip4(const struct sockaddr *sa1,
348				const struct sockaddr *sa2)
349{
350	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
351	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
352
353	return nfs_sockaddr_match_ipaddr4(sa1, sa2) &&
354		(sin1->sin_port == sin2->sin_port);
355}
356
357#if defined(CONFIG_NFS_V4_1)
358/*
359 * Test if two socket addresses represent the same actual socket,
360 * by comparing (only) relevant fields, excluding the port number.
361 */
362int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
363			      const struct sockaddr *sa2)
364{
365	if (sa1->sa_family != sa2->sa_family)
366		return 0;
367
368	switch (sa1->sa_family) {
369	case AF_INET:
370		return nfs_sockaddr_match_ipaddr4(sa1, sa2);
371	case AF_INET6:
372		return nfs_sockaddr_match_ipaddr6(sa1, sa2);
373	}
374	return 0;
375}
376EXPORT_SYMBOL_GPL(nfs_sockaddr_match_ipaddr);
377#endif /* CONFIG_NFS_V4_1 */
378
379/*
380 * Test if two socket addresses represent the same actual socket,
381 * by comparing (only) relevant fields, including the port number.
382 */
383static int nfs_sockaddr_cmp(const struct sockaddr *sa1,
384			    const struct sockaddr *sa2)
385{
386	if (sa1->sa_family != sa2->sa_family)
387		return 0;
388
389	switch (sa1->sa_family) {
390	case AF_INET:
391		return nfs_sockaddr_cmp_ip4(sa1, sa2);
392	case AF_INET6:
393		return nfs_sockaddr_cmp_ip6(sa1, sa2);
394	}
395	return 0;
396}
397
398/*
399 * Find an nfs_client on the list that matches the initialisation data
400 * that is supplied.
401 */
402static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
403{
404	struct nfs_client *clp;
405	const struct sockaddr *sap = data->addr;
406	struct nfs_net *nn = net_generic(data->net, nfs_net_id);
407
408	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
409	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
410		/* Don't match clients that failed to initialise properly */
411		if (clp->cl_cons_state < 0)
412			continue;
413
414		/* Different NFS versions cannot share the same nfs_client */
415		if (clp->rpc_ops != data->nfs_mod->rpc_ops)
416			continue;
417
418		if (clp->cl_proto != data->proto)
419			continue;
420		/* Match nfsv4 minorversion */
421		if (clp->cl_minorversion != data->minorversion)
422			continue;
423		/* Match the full socket address */
424		if (!nfs_sockaddr_cmp(sap, clap))
425			continue;
426
427		atomic_inc(&clp->cl_count);
428		return clp;
429	}
430	return NULL;
431}
432
433static bool nfs_client_init_is_complete(const struct nfs_client *clp)
434{
435	return clp->cl_cons_state <= NFS_CS_READY;
436}
437
438int nfs_wait_client_init_complete(const struct nfs_client *clp)
439{
440	return wait_event_killable(nfs_client_active_wq,
441			nfs_client_init_is_complete(clp));
442}
443EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
444
445/*
446 * Found an existing client.  Make sure it's ready before returning.
447 */
448static struct nfs_client *
449nfs_found_client(const struct nfs_client_initdata *cl_init,
450		 struct nfs_client *clp)
451{
452	int error;
453
454	error = nfs_wait_client_init_complete(clp);
455	if (error < 0) {
456		nfs_put_client(clp);
457		return ERR_PTR(-ERESTARTSYS);
458	}
459
460	if (clp->cl_cons_state < NFS_CS_READY) {
461		error = clp->cl_cons_state;
462		nfs_put_client(clp);
463		return ERR_PTR(error);
464	}
465
466	smp_rmb();
467
468	dprintk("<-- %s found nfs_client %p for %s\n",
469		__func__, clp, cl_init->hostname ?: "");
470	return clp;
471}
472
473/*
474 * Look up a client by IP address and protocol version
475 * - creates a new record if one doesn't yet exist
476 */
477struct nfs_client *
478nfs_get_client(const struct nfs_client_initdata *cl_init,
479	       const struct rpc_timeout *timeparms,
480	       const char *ip_addr,
481	       rpc_authflavor_t authflavour)
482{
483	struct nfs_client *clp, *new = NULL;
484	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
485	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
486
487	if (cl_init->hostname == NULL) {
488		WARN_ON(1);
489		return NULL;
490	}
491
492	dprintk("--> nfs_get_client(%s,v%u)\n",
493		cl_init->hostname, rpc_ops->version);
494
495	/* see if the client already exists */
496	do {
497		spin_lock(&nn->nfs_client_lock);
498
499		clp = nfs_match_client(cl_init);
500		if (clp) {
501			spin_unlock(&nn->nfs_client_lock);
502			if (new)
503				new->rpc_ops->free_client(new);
504			return nfs_found_client(cl_init, clp);
505		}
506		if (new) {
507			list_add_tail(&new->cl_share_link,
508					&nn->nfs_client_list);
509			spin_unlock(&nn->nfs_client_lock);
510			new->cl_flags = cl_init->init_flags;
511			return rpc_ops->init_client(new, timeparms, ip_addr);
512		}
513
514		spin_unlock(&nn->nfs_client_lock);
515
516		new = rpc_ops->alloc_client(cl_init);
517	} while (!IS_ERR(new));
518
519	dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
520		cl_init->hostname, PTR_ERR(new));
521	return new;
522}
523EXPORT_SYMBOL_GPL(nfs_get_client);
524
525/*
526 * Mark a server as ready or failed
527 */
528void nfs_mark_client_ready(struct nfs_client *clp, int state)
529{
530	smp_wmb();
531	clp->cl_cons_state = state;
532	wake_up_all(&nfs_client_active_wq);
533}
534EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
535
536/*
537 * Initialise the timeout values for a connection
538 */
539void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
540				    unsigned int timeo, unsigned int retrans)
541{
542	to->to_initval = timeo * HZ / 10;
543	to->to_retries = retrans;
544
545	switch (proto) {
546	case XPRT_TRANSPORT_TCP:
547	case XPRT_TRANSPORT_RDMA:
548		if (to->to_retries == 0)
549			to->to_retries = NFS_DEF_TCP_RETRANS;
550		if (to->to_initval == 0)
551			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
552		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
553			to->to_initval = NFS_MAX_TCP_TIMEOUT;
554		to->to_increment = to->to_initval;
555		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
556		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
557			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
558		if (to->to_maxval < to->to_initval)
559			to->to_maxval = to->to_initval;
560		to->to_exponential = 0;
561		break;
562	case XPRT_TRANSPORT_UDP:
563		if (to->to_retries == 0)
564			to->to_retries = NFS_DEF_UDP_RETRANS;
565		if (!to->to_initval)
566			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
567		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
568			to->to_initval = NFS_MAX_UDP_TIMEOUT;
569		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
570		to->to_exponential = 1;
571		break;
572	default:
573		BUG();
574	}
575}
576EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
577
578/*
579 * Create an RPC client handle
580 */
581int nfs_create_rpc_client(struct nfs_client *clp,
582			  const struct rpc_timeout *timeparms,
583			  rpc_authflavor_t flavor)
584{
585	struct rpc_clnt		*clnt = NULL;
586	struct rpc_create_args args = {
587		.net		= clp->cl_net,
588		.protocol	= clp->cl_proto,
589		.address	= (struct sockaddr *)&clp->cl_addr,
590		.addrsize	= clp->cl_addrlen,
591		.timeout	= timeparms,
592		.servername	= clp->cl_hostname,
593		.program	= &nfs_program,
594		.version	= clp->rpc_ops->version,
595		.authflavor	= flavor,
596	};
597
598	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
599		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
600	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
601		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
602	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
603		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
604	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
605		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
606
607	if (!IS_ERR(clp->cl_rpcclient))
608		return 0;
609
610	clnt = rpc_create(&args);
611	if (IS_ERR(clnt)) {
612		dprintk("%s: cannot create RPC client. Error = %ld\n",
613				__func__, PTR_ERR(clnt));
614		return PTR_ERR(clnt);
615	}
616
617	clp->cl_rpcclient = clnt;
618	return 0;
619}
620EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
621
622/*
623 * Version 2 or 3 client destruction
624 */
625static void nfs_destroy_server(struct nfs_server *server)
626{
627	if (server->nlm_host)
628		nlmclnt_done(server->nlm_host);
629}
630
631/*
632 * Version 2 or 3 lockd setup
633 */
634static int nfs_start_lockd(struct nfs_server *server)
635{
636	struct nlm_host *host;
637	struct nfs_client *clp = server->nfs_client;
638	struct nlmclnt_initdata nlm_init = {
639		.hostname	= clp->cl_hostname,
640		.address	= (struct sockaddr *)&clp->cl_addr,
641		.addrlen	= clp->cl_addrlen,
642		.nfs_version	= clp->rpc_ops->version,
643		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
644					1 : 0,
645		.net		= clp->cl_net,
646	};
647
648	if (nlm_init.nfs_version > 3)
649		return 0;
650	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
651			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
652		return 0;
653
654	switch (clp->cl_proto) {
655		default:
656			nlm_init.protocol = IPPROTO_TCP;
657			break;
658		case XPRT_TRANSPORT_UDP:
659			nlm_init.protocol = IPPROTO_UDP;
660	}
661
662	host = nlmclnt_init(&nlm_init);
663	if (IS_ERR(host))
664		return PTR_ERR(host);
665
666	server->nlm_host = host;
667	server->destroy = nfs_destroy_server;
668	return 0;
669}
670
671/*
672 * Create a general RPC client
673 */
674int nfs_init_server_rpcclient(struct nfs_server *server,
675		const struct rpc_timeout *timeo,
676		rpc_authflavor_t pseudoflavour)
677{
678	struct nfs_client *clp = server->nfs_client;
679
680	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
681							pseudoflavour);
682	if (IS_ERR(server->client)) {
683		dprintk("%s: couldn't create rpc_client!\n", __func__);
684		return PTR_ERR(server->client);
685	}
686
687	memcpy(&server->client->cl_timeout_default,
688			timeo,
689			sizeof(server->client->cl_timeout_default));
690	server->client->cl_timeout = &server->client->cl_timeout_default;
691	server->client->cl_softrtry = 0;
692	if (server->flags & NFS_MOUNT_SOFT)
693		server->client->cl_softrtry = 1;
694
695	return 0;
696}
697EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
698
699/**
700 * nfs_init_client - Initialise an NFS2 or NFS3 client
701 *
702 * @clp: nfs_client to initialise
703 * @timeparms: timeout parameters for underlying RPC transport
704 * @ip_addr: IP presentation address (not used)
705 *
706 * Returns pointer to an NFS client, or an ERR_PTR value.
707 */
708struct nfs_client *nfs_init_client(struct nfs_client *clp,
709		    const struct rpc_timeout *timeparms,
710		    const char *ip_addr)
711{
712	int error;
713
714	if (clp->cl_cons_state == NFS_CS_READY) {
715		/* the client is already initialised */
716		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
717		return clp;
718	}
719
720	/*
721	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
722	 * - RFC 2623, sec 2.3.2
723	 */
724	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
725	if (error < 0)
726		goto error;
727	nfs_mark_client_ready(clp, NFS_CS_READY);
728	return clp;
729
730error:
731	nfs_mark_client_ready(clp, error);
732	nfs_put_client(clp);
733	dprintk("<-- nfs_init_client() = xerror %d\n", error);
734	return ERR_PTR(error);
735}
736EXPORT_SYMBOL_GPL(nfs_init_client);
737
738/*
739 * Create a version 2 or 3 client
740 */
741static int nfs_init_server(struct nfs_server *server,
742			   const struct nfs_parsed_mount_data *data,
743			   struct nfs_subversion *nfs_mod)
744{
745	struct nfs_client_initdata cl_init = {
746		.hostname = data->nfs_server.hostname,
747		.addr = (const struct sockaddr *)&data->nfs_server.address,
748		.addrlen = data->nfs_server.addrlen,
749		.nfs_mod = nfs_mod,
750		.proto = data->nfs_server.protocol,
751		.net = data->net,
752	};
753	struct rpc_timeout timeparms;
754	struct nfs_client *clp;
755	int error;
756
757	dprintk("--> nfs_init_server()\n");
758
759	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
760			data->timeo, data->retrans);
761	if (data->flags & NFS_MOUNT_NORESVPORT)
762		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
763
764	/* Allocate or find a client reference we can use */
765	clp = nfs_get_client(&cl_init, &timeparms, NULL, RPC_AUTH_UNIX);
766	if (IS_ERR(clp)) {
767		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
768		return PTR_ERR(clp);
769	}
770
771	server->nfs_client = clp;
772
773	/* Initialise the client representation from the mount data */
774	server->flags = data->flags;
775	server->options = data->options;
776	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
777		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
778		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
779
780	if (data->rsize)
781		server->rsize = nfs_block_size(data->rsize, NULL);
782	if (data->wsize)
783		server->wsize = nfs_block_size(data->wsize, NULL);
784
785	server->acregmin = data->acregmin * HZ;
786	server->acregmax = data->acregmax * HZ;
787	server->acdirmin = data->acdirmin * HZ;
788	server->acdirmax = data->acdirmax * HZ;
789
790	/* Start lockd here, before we might error out */
791	error = nfs_start_lockd(server);
792	if (error < 0)
793		goto error;
794
795	server->port = data->nfs_server.port;
796	server->auth_info = data->auth_info;
797
798	error = nfs_init_server_rpcclient(server, &timeparms,
799					  data->selected_flavor);
800	if (error < 0)
801		goto error;
802
803	/* Preserve the values of mount_server-related mount options */
804	if (data->mount_server.addrlen) {
805		memcpy(&server->mountd_address, &data->mount_server.address,
806			data->mount_server.addrlen);
807		server->mountd_addrlen = data->mount_server.addrlen;
808	}
809	server->mountd_version = data->mount_server.version;
810	server->mountd_port = data->mount_server.port;
811	server->mountd_protocol = data->mount_server.protocol;
812
813	server->namelen  = data->namlen;
814	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
815	return 0;
816
817error:
818	server->nfs_client = NULL;
819	nfs_put_client(clp);
820	dprintk("<-- nfs_init_server() = xerror %d\n", error);
821	return error;
822}
823
824/*
825 * Load up the server record from information gained in an fsinfo record
826 */
827static void nfs_server_set_fsinfo(struct nfs_server *server,
828				  struct nfs_fh *mntfh,
829				  struct nfs_fsinfo *fsinfo)
830{
831	unsigned long max_rpc_payload;
832
833	/* Work out a lot of parameters */
834	if (server->rsize == 0)
835		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
836	if (server->wsize == 0)
837		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
838
839	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
840		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
841	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
842		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
843
844	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
845	if (server->rsize > max_rpc_payload)
846		server->rsize = max_rpc_payload;
847	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
848		server->rsize = NFS_MAX_FILE_IO_SIZE;
849	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
850
851	server->backing_dev_info.name = "nfs";
852	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
853
854	if (server->wsize > max_rpc_payload)
855		server->wsize = max_rpc_payload;
856	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
857		server->wsize = NFS_MAX_FILE_IO_SIZE;
858	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
859
860	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
861
862	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
863	if (server->dtsize > PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES)
864		server->dtsize = PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES;
865	if (server->dtsize > server->rsize)
866		server->dtsize = server->rsize;
867
868	if (server->flags & NFS_MOUNT_NOAC) {
869		server->acregmin = server->acregmax = 0;
870		server->acdirmin = server->acdirmax = 0;
871	}
872
873	server->maxfilesize = fsinfo->maxfilesize;
874
875	server->time_delta = fsinfo->time_delta;
876
877	/* We're airborne Set socket buffersize */
878	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
879}
880
881/*
882 * Probe filesystem information, including the FSID on v2/v3
883 */
884int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
885{
886	struct nfs_fsinfo fsinfo;
887	struct nfs_client *clp = server->nfs_client;
888	int error;
889
890	dprintk("--> nfs_probe_fsinfo()\n");
891
892	if (clp->rpc_ops->set_capabilities != NULL) {
893		error = clp->rpc_ops->set_capabilities(server, mntfh);
894		if (error < 0)
895			goto out_error;
896	}
897
898	fsinfo.fattr = fattr;
899	fsinfo.layouttype = 0;
900	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
901	if (error < 0)
902		goto out_error;
903
904	nfs_server_set_fsinfo(server, mntfh, &fsinfo);
905
906	/* Get some general file system info */
907	if (server->namelen == 0) {
908		struct nfs_pathconf pathinfo;
909
910		pathinfo.fattr = fattr;
911		nfs_fattr_init(fattr);
912
913		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
914			server->namelen = pathinfo.max_namelen;
915	}
916
917	dprintk("<-- nfs_probe_fsinfo() = 0\n");
918	return 0;
919
920out_error:
921	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
922	return error;
923}
924EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
925
926/*
927 * Copy useful information when duplicating a server record
928 */
929void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
930{
931	target->flags = source->flags;
932	target->rsize = source->rsize;
933	target->wsize = source->wsize;
934	target->acregmin = source->acregmin;
935	target->acregmax = source->acregmax;
936	target->acdirmin = source->acdirmin;
937	target->acdirmax = source->acdirmax;
938	target->caps = source->caps;
939	target->options = source->options;
940	target->auth_info = source->auth_info;
941}
942EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
943
944void nfs_server_insert_lists(struct nfs_server *server)
945{
946	struct nfs_client *clp = server->nfs_client;
947	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
948
949	spin_lock(&nn->nfs_client_lock);
950	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
951	list_add_tail(&server->master_link, &nn->nfs_volume_list);
952	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
953	spin_unlock(&nn->nfs_client_lock);
954
955}
956EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
957
958void nfs_server_remove_lists(struct nfs_server *server)
959{
960	struct nfs_client *clp = server->nfs_client;
961	struct nfs_net *nn;
962
963	if (clp == NULL)
964		return;
965	nn = net_generic(clp->cl_net, nfs_net_id);
966	spin_lock(&nn->nfs_client_lock);
967	list_del_rcu(&server->client_link);
968	if (list_empty(&clp->cl_superblocks))
969		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
970	list_del(&server->master_link);
971	spin_unlock(&nn->nfs_client_lock);
972
973	synchronize_rcu();
974}
975EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
976
977/*
978 * Allocate and initialise a server record
979 */
980struct nfs_server *nfs_alloc_server(void)
981{
982	struct nfs_server *server;
983
984	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
985	if (!server)
986		return NULL;
987
988	server->client = server->client_acl = ERR_PTR(-EINVAL);
989
990	/* Zero out the NFS state stuff */
991	INIT_LIST_HEAD(&server->client_link);
992	INIT_LIST_HEAD(&server->master_link);
993	INIT_LIST_HEAD(&server->delegations);
994	INIT_LIST_HEAD(&server->layouts);
995	INIT_LIST_HEAD(&server->state_owners_lru);
996
997	atomic_set(&server->active, 0);
998
999	server->io_stats = nfs_alloc_iostats();
1000	if (!server->io_stats) {
1001		kfree(server);
1002		return NULL;
1003	}
1004
1005	if (bdi_init(&server->backing_dev_info)) {
1006		nfs_free_iostats(server->io_stats);
1007		kfree(server);
1008		return NULL;
1009	}
1010
1011	ida_init(&server->openowner_id);
1012	ida_init(&server->lockowner_id);
1013	pnfs_init_server(server);
1014
1015	return server;
1016}
1017EXPORT_SYMBOL_GPL(nfs_alloc_server);
1018
1019/*
1020 * Free up a server record
1021 */
1022void nfs_free_server(struct nfs_server *server)
1023{
1024	dprintk("--> nfs_free_server()\n");
1025
1026	nfs_server_remove_lists(server);
1027
1028	if (server->destroy != NULL)
1029		server->destroy(server);
1030
1031	if (!IS_ERR(server->client_acl))
1032		rpc_shutdown_client(server->client_acl);
1033	if (!IS_ERR(server->client))
1034		rpc_shutdown_client(server->client);
1035
1036	nfs_put_client(server->nfs_client);
1037
1038	ida_destroy(&server->lockowner_id);
1039	ida_destroy(&server->openowner_id);
1040	nfs_free_iostats(server->io_stats);
1041	bdi_destroy(&server->backing_dev_info);
1042	kfree(server);
1043	nfs_release_automount_timer();
1044	dprintk("<-- nfs_free_server()\n");
1045}
1046EXPORT_SYMBOL_GPL(nfs_free_server);
1047
1048/*
1049 * Create a version 2 or 3 volume record
1050 * - keyed on server and FSID
1051 */
1052struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
1053				     struct nfs_subversion *nfs_mod)
1054{
1055	struct nfs_server *server;
1056	struct nfs_fattr *fattr;
1057	int error;
1058
1059	server = nfs_alloc_server();
1060	if (!server)
1061		return ERR_PTR(-ENOMEM);
1062
1063	error = -ENOMEM;
1064	fattr = nfs_alloc_fattr();
1065	if (fattr == NULL)
1066		goto error;
1067
1068	/* Get a client representation */
1069	error = nfs_init_server(server, mount_info->parsed, nfs_mod);
1070	if (error < 0)
1071		goto error;
1072
1073	/* Probe the root fh to retrieve its FSID */
1074	error = nfs_probe_fsinfo(server, mount_info->mntfh, fattr);
1075	if (error < 0)
1076		goto error;
1077	if (server->nfs_client->rpc_ops->version == 3) {
1078		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
1079			server->namelen = NFS3_MAXNAMLEN;
1080		if (!(mount_info->parsed->flags & NFS_MOUNT_NORDIRPLUS))
1081			server->caps |= NFS_CAP_READDIRPLUS;
1082	} else {
1083		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
1084			server->namelen = NFS2_MAXNAMLEN;
1085	}
1086
1087	if (!(fattr->valid & NFS_ATTR_FATTR)) {
1088		error = nfs_mod->rpc_ops->getattr(server, mount_info->mntfh, fattr, NULL);
1089		if (error < 0) {
1090			dprintk("nfs_create_server: getattr error = %d\n", -error);
1091			goto error;
1092		}
1093	}
1094	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1095
1096	dprintk("Server FSID: %llx:%llx\n",
1097		(unsigned long long) server->fsid.major,
1098		(unsigned long long) server->fsid.minor);
1099
1100	nfs_server_insert_lists(server);
1101	server->mount_time = jiffies;
1102	nfs_free_fattr(fattr);
1103	return server;
1104
1105error:
1106	nfs_free_fattr(fattr);
1107	nfs_free_server(server);
1108	return ERR_PTR(error);
1109}
1110EXPORT_SYMBOL_GPL(nfs_create_server);
1111
1112/*
1113 * Clone an NFS2, NFS3 or NFS4 server record
1114 */
1115struct nfs_server *nfs_clone_server(struct nfs_server *source,
1116				    struct nfs_fh *fh,
1117				    struct nfs_fattr *fattr,
1118				    rpc_authflavor_t flavor)
1119{
1120	struct nfs_server *server;
1121	struct nfs_fattr *fattr_fsinfo;
1122	int error;
1123
1124	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1125		(unsigned long long) fattr->fsid.major,
1126		(unsigned long long) fattr->fsid.minor);
1127
1128	server = nfs_alloc_server();
1129	if (!server)
1130		return ERR_PTR(-ENOMEM);
1131
1132	error = -ENOMEM;
1133	fattr_fsinfo = nfs_alloc_fattr();
1134	if (fattr_fsinfo == NULL)
1135		goto out_free_server;
1136
1137	/* Copy data from the source */
1138	server->nfs_client = source->nfs_client;
1139	server->destroy = source->destroy;
1140	atomic_inc(&server->nfs_client->cl_count);
1141	nfs_server_copy_userdata(server, source);
1142
1143	server->fsid = fattr->fsid;
1144
1145	error = nfs_init_server_rpcclient(server,
1146			source->client->cl_timeout,
1147			flavor);
1148	if (error < 0)
1149		goto out_free_server;
1150
1151	/* probe the filesystem info for this server filesystem */
1152	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1153	if (error < 0)
1154		goto out_free_server;
1155
1156	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1157		server->namelen = NFS4_MAXNAMLEN;
1158
1159	dprintk("Cloned FSID: %llx:%llx\n",
1160		(unsigned long long) server->fsid.major,
1161		(unsigned long long) server->fsid.minor);
1162
1163	error = nfs_start_lockd(server);
1164	if (error < 0)
1165		goto out_free_server;
1166
1167	nfs_server_insert_lists(server);
1168	server->mount_time = jiffies;
1169
1170	nfs_free_fattr(fattr_fsinfo);
1171	dprintk("<-- nfs_clone_server() = %p\n", server);
1172	return server;
1173
1174out_free_server:
1175	nfs_free_fattr(fattr_fsinfo);
1176	nfs_free_server(server);
1177	dprintk("<-- nfs_clone_server() = error %d\n", error);
1178	return ERR_PTR(error);
1179}
1180EXPORT_SYMBOL_GPL(nfs_clone_server);
1181
1182void nfs_clients_init(struct net *net)
1183{
1184	struct nfs_net *nn = net_generic(net, nfs_net_id);
1185
1186	INIT_LIST_HEAD(&nn->nfs_client_list);
1187	INIT_LIST_HEAD(&nn->nfs_volume_list);
1188#if IS_ENABLED(CONFIG_NFS_V4)
1189	idr_init(&nn->cb_ident_idr);
1190#endif
1191	spin_lock_init(&nn->nfs_client_lock);
1192	nn->boot_time = CURRENT_TIME;
1193}
1194
1195#ifdef CONFIG_PROC_FS
1196static struct proc_dir_entry *proc_fs_nfs;
1197
1198static int nfs_server_list_open(struct inode *inode, struct file *file);
1199static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1200static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1201static void nfs_server_list_stop(struct seq_file *p, void *v);
1202static int nfs_server_list_show(struct seq_file *m, void *v);
1203
1204static const struct seq_operations nfs_server_list_ops = {
1205	.start	= nfs_server_list_start,
1206	.next	= nfs_server_list_next,
1207	.stop	= nfs_server_list_stop,
1208	.show	= nfs_server_list_show,
1209};
1210
1211static const struct file_operations nfs_server_list_fops = {
1212	.open		= nfs_server_list_open,
1213	.read		= seq_read,
1214	.llseek		= seq_lseek,
1215	.release	= seq_release_net,
1216	.owner		= THIS_MODULE,
1217};
1218
1219static int nfs_volume_list_open(struct inode *inode, struct file *file);
1220static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1221static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1222static void nfs_volume_list_stop(struct seq_file *p, void *v);
1223static int nfs_volume_list_show(struct seq_file *m, void *v);
1224
1225static const struct seq_operations nfs_volume_list_ops = {
1226	.start	= nfs_volume_list_start,
1227	.next	= nfs_volume_list_next,
1228	.stop	= nfs_volume_list_stop,
1229	.show	= nfs_volume_list_show,
1230};
1231
1232static const struct file_operations nfs_volume_list_fops = {
1233	.open		= nfs_volume_list_open,
1234	.read		= seq_read,
1235	.llseek		= seq_lseek,
1236	.release	= seq_release_net,
1237	.owner		= THIS_MODULE,
1238};
1239
1240/*
1241 * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1242 * we're dealing
1243 */
1244static int nfs_server_list_open(struct inode *inode, struct file *file)
1245{
1246	return seq_open_net(inode, file, &nfs_server_list_ops,
1247			   sizeof(struct seq_net_private));
1248}
1249
1250/*
1251 * set up the iterator to start reading from the server list and return the first item
1252 */
1253static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1254				__acquires(&nn->nfs_client_lock)
1255{
1256	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1257
1258	/* lock the list against modification */
1259	spin_lock(&nn->nfs_client_lock);
1260	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1261}
1262
1263/*
1264 * move to next server
1265 */
1266static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1267{
1268	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1269
1270	return seq_list_next(v, &nn->nfs_client_list, pos);
1271}
1272
1273/*
1274 * clean up after reading from the transports list
1275 */
1276static void nfs_server_list_stop(struct seq_file *p, void *v)
1277				__releases(&nn->nfs_client_lock)
1278{
1279	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1280
1281	spin_unlock(&nn->nfs_client_lock);
1282}
1283
1284/*
1285 * display a header line followed by a load of call lines
1286 */
1287static int nfs_server_list_show(struct seq_file *m, void *v)
1288{
1289	struct nfs_client *clp;
1290	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1291
1292	/* display header on line 1 */
1293	if (v == &nn->nfs_client_list) {
1294		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1295		return 0;
1296	}
1297
1298	/* display one transport per line on subsequent lines */
1299	clp = list_entry(v, struct nfs_client, cl_share_link);
1300
1301	/* Check if the client is initialized */
1302	if (clp->cl_cons_state != NFS_CS_READY)
1303		return 0;
1304
1305	rcu_read_lock();
1306	seq_printf(m, "v%u %s %s %3d %s\n",
1307		   clp->rpc_ops->version,
1308		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1309		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1310		   atomic_read(&clp->cl_count),
1311		   clp->cl_hostname);
1312	rcu_read_unlock();
1313
1314	return 0;
1315}
1316
1317/*
1318 * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1319 */
1320static int nfs_volume_list_open(struct inode *inode, struct file *file)
1321{
1322	return seq_open_net(inode, file, &nfs_volume_list_ops,
1323			   sizeof(struct seq_net_private));
1324}
1325
1326/*
1327 * set up the iterator to start reading from the volume list and return the first item
1328 */
1329static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1330				__acquires(&nn->nfs_client_lock)
1331{
1332	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1333
1334	/* lock the list against modification */
1335	spin_lock(&nn->nfs_client_lock);
1336	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1337}
1338
1339/*
1340 * move to next volume
1341 */
1342static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1343{
1344	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1345
1346	return seq_list_next(v, &nn->nfs_volume_list, pos);
1347}
1348
1349/*
1350 * clean up after reading from the transports list
1351 */
1352static void nfs_volume_list_stop(struct seq_file *p, void *v)
1353				__releases(&nn->nfs_client_lock)
1354{
1355	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1356
1357	spin_unlock(&nn->nfs_client_lock);
1358}
1359
1360/*
1361 * display a header line followed by a load of call lines
1362 */
1363static int nfs_volume_list_show(struct seq_file *m, void *v)
1364{
1365	struct nfs_server *server;
1366	struct nfs_client *clp;
1367	char dev[8], fsid[17];
1368	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1369
1370	/* display header on line 1 */
1371	if (v == &nn->nfs_volume_list) {
1372		seq_puts(m, "NV SERVER   PORT DEV     FSID              FSC\n");
1373		return 0;
1374	}
1375	/* display one transport per line on subsequent lines */
1376	server = list_entry(v, struct nfs_server, master_link);
1377	clp = server->nfs_client;
1378
1379	snprintf(dev, 8, "%u:%u",
1380		 MAJOR(server->s_dev), MINOR(server->s_dev));
1381
1382	snprintf(fsid, 17, "%llx:%llx",
1383		 (unsigned long long) server->fsid.major,
1384		 (unsigned long long) server->fsid.minor);
1385
1386	rcu_read_lock();
1387	seq_printf(m, "v%u %s %s %-7s %-17s %s\n",
1388		   clp->rpc_ops->version,
1389		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1390		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1391		   dev,
1392		   fsid,
1393		   nfs_server_fscache_state(server));
1394	rcu_read_unlock();
1395
1396	return 0;
1397}
1398
1399int nfs_fs_proc_net_init(struct net *net)
1400{
1401	struct nfs_net *nn = net_generic(net, nfs_net_id);
1402	struct proc_dir_entry *p;
1403
1404	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1405	if (!nn->proc_nfsfs)
1406		goto error_0;
1407
1408	/* a file of servers with which we're dealing */
1409	p = proc_create("servers", S_IFREG|S_IRUGO,
1410			nn->proc_nfsfs, &nfs_server_list_fops);
1411	if (!p)
1412		goto error_1;
1413
1414	/* a file of volumes that we have mounted */
1415	p = proc_create("volumes", S_IFREG|S_IRUGO,
1416			nn->proc_nfsfs, &nfs_volume_list_fops);
1417	if (!p)
1418		goto error_1;
1419	return 0;
1420
1421error_1:
1422	remove_proc_subtree("nfsfs", net->proc_net);
1423error_0:
1424	return -ENOMEM;
1425}
1426
1427void nfs_fs_proc_net_exit(struct net *net)
1428{
1429	remove_proc_subtree("nfsfs", net->proc_net);
1430}
1431
1432/*
1433 * initialise the /proc/fs/nfsfs/ directory
1434 */
1435int __init nfs_fs_proc_init(void)
1436{
1437	struct proc_dir_entry *p;
1438
1439	proc_fs_nfs = proc_mkdir("fs/nfsfs", NULL);
1440	if (!proc_fs_nfs)
1441		goto error_0;
1442
1443	/* a file of servers with which we're dealing */
1444	p = proc_symlink("servers", proc_fs_nfs, "../../net/nfsfs/servers");
1445	if (!p)
1446		goto error_1;
1447
1448	/* a file of volumes that we have mounted */
1449	p = proc_symlink("volumes", proc_fs_nfs, "../../net/nfsfs/volumes");
1450	if (!p)
1451		goto error_2;
1452	return 0;
1453
1454error_2:
1455	remove_proc_entry("servers", proc_fs_nfs);
1456error_1:
1457	remove_proc_entry("fs/nfsfs", NULL);
1458error_0:
1459	return -ENOMEM;
1460}
1461
1462/*
1463 * clean up the /proc/fs/nfsfs/ directory
1464 */
1465void nfs_fs_proc_exit(void)
1466{
1467	remove_proc_entry("volumes", proc_fs_nfs);
1468	remove_proc_entry("servers", proc_fs_nfs);
1469	remove_proc_entry("fs/nfsfs", NULL);
1470}
1471
1472#endif /* CONFIG_PROC_FS */
1473