xref: /openbmc/linux/fs/nfs/client.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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/nfs_idmap.h>
35 #include <linux/vfs.h>
36 #include <linux/inet.h>
37 #include <linux/nfs_xdr.h>
38 
39 #include <asm/system.h>
40 
41 #include "nfs4_fs.h"
42 #include "callback.h"
43 #include "delegation.h"
44 #include "iostat.h"
45 #include "internal.h"
46 
47 #define NFSDBG_FACILITY		NFSDBG_CLIENT
48 
49 static DEFINE_SPINLOCK(nfs_client_lock);
50 static LIST_HEAD(nfs_client_list);
51 static LIST_HEAD(nfs_volume_list);
52 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
53 
54 /*
55  * RPC cruft for NFS
56  */
57 static struct rpc_version *nfs_version[5] = {
58 	[2]			= &nfs_version2,
59 #ifdef CONFIG_NFS_V3
60 	[3]			= &nfs_version3,
61 #endif
62 #ifdef CONFIG_NFS_V4
63 	[4]			= &nfs_version4,
64 #endif
65 };
66 
67 struct rpc_program nfs_program = {
68 	.name			= "nfs",
69 	.number			= NFS_PROGRAM,
70 	.nrvers			= ARRAY_SIZE(nfs_version),
71 	.version		= nfs_version,
72 	.stats			= &nfs_rpcstat,
73 	.pipe_dir_name		= "/nfs",
74 };
75 
76 struct rpc_stat nfs_rpcstat = {
77 	.program		= &nfs_program
78 };
79 
80 
81 #ifdef CONFIG_NFS_V3_ACL
82 static struct rpc_stat		nfsacl_rpcstat = { &nfsacl_program };
83 static struct rpc_version *	nfsacl_version[] = {
84 	[3]			= &nfsacl_version3,
85 };
86 
87 struct rpc_program		nfsacl_program = {
88 	.name			= "nfsacl",
89 	.number			= NFS_ACL_PROGRAM,
90 	.nrvers			= ARRAY_SIZE(nfsacl_version),
91 	.version		= nfsacl_version,
92 	.stats			= &nfsacl_rpcstat,
93 };
94 #endif  /* CONFIG_NFS_V3_ACL */
95 
96 /*
97  * Allocate a shared client record
98  *
99  * Since these are allocated/deallocated very rarely, we don't
100  * bother putting them in a slab cache...
101  */
102 static struct nfs_client *nfs_alloc_client(const char *hostname,
103 					   const struct sockaddr_in *addr,
104 					   int nfsversion)
105 {
106 	struct nfs_client *clp;
107 
108 	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
109 		goto error_0;
110 
111 	if (nfsversion == 4) {
112 		if (nfs_callback_up() < 0)
113 			goto error_2;
114 		__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
115 	}
116 
117 	atomic_set(&clp->cl_count, 1);
118 	clp->cl_cons_state = NFS_CS_INITING;
119 
120 	clp->cl_nfsversion = nfsversion;
121 	memcpy(&clp->cl_addr, addr, sizeof(clp->cl_addr));
122 
123 	if (hostname) {
124 		clp->cl_hostname = kstrdup(hostname, GFP_KERNEL);
125 		if (!clp->cl_hostname)
126 			goto error_3;
127 	}
128 
129 	INIT_LIST_HEAD(&clp->cl_superblocks);
130 	clp->cl_rpcclient = ERR_PTR(-EINVAL);
131 
132 #ifdef CONFIG_NFS_V4
133 	init_rwsem(&clp->cl_sem);
134 	INIT_LIST_HEAD(&clp->cl_delegations);
135 	spin_lock_init(&clp->cl_lock);
136 	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
137 	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
138 	clp->cl_boot_time = CURRENT_TIME;
139 	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
140 #endif
141 
142 	return clp;
143 
144 error_3:
145 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
146 		nfs_callback_down();
147 error_2:
148 	kfree(clp);
149 error_0:
150 	return NULL;
151 }
152 
153 static void nfs4_shutdown_client(struct nfs_client *clp)
154 {
155 #ifdef CONFIG_NFS_V4
156 	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
157 		nfs4_kill_renewd(clp);
158 	BUG_ON(!RB_EMPTY_ROOT(&clp->cl_state_owners));
159 	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
160 		nfs_idmap_delete(clp);
161 #endif
162 }
163 
164 /*
165  * Destroy a shared client record
166  */
167 static void nfs_free_client(struct nfs_client *clp)
168 {
169 	dprintk("--> nfs_free_client(%d)\n", clp->cl_nfsversion);
170 
171 	nfs4_shutdown_client(clp);
172 
173 	/* -EIO all pending I/O */
174 	if (!IS_ERR(clp->cl_rpcclient))
175 		rpc_shutdown_client(clp->cl_rpcclient);
176 
177 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
178 		nfs_callback_down();
179 
180 	kfree(clp->cl_hostname);
181 	kfree(clp);
182 
183 	dprintk("<-- nfs_free_client()\n");
184 }
185 
186 /*
187  * Release a reference to a shared client record
188  */
189 void nfs_put_client(struct nfs_client *clp)
190 {
191 	if (!clp)
192 		return;
193 
194 	dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
195 
196 	if (atomic_dec_and_lock(&clp->cl_count, &nfs_client_lock)) {
197 		list_del(&clp->cl_share_link);
198 		spin_unlock(&nfs_client_lock);
199 
200 		BUG_ON(!list_empty(&clp->cl_superblocks));
201 
202 		nfs_free_client(clp);
203 	}
204 }
205 
206 /*
207  * Find a client by address
208  * - caller must hold nfs_client_lock
209  */
210 static struct nfs_client *__nfs_find_client(const struct sockaddr_in *addr, int nfsversion, int match_port)
211 {
212 	struct nfs_client *clp;
213 
214 	list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
215 		/* Don't match clients that failed to initialise properly */
216 		if (clp->cl_cons_state < 0)
217 			continue;
218 
219 		/* Different NFS versions cannot share the same nfs_client */
220 		if (clp->cl_nfsversion != nfsversion)
221 			continue;
222 
223 		if (memcmp(&clp->cl_addr.sin_addr, &addr->sin_addr,
224 			   sizeof(clp->cl_addr.sin_addr)) != 0)
225 			continue;
226 
227 		if (!match_port || clp->cl_addr.sin_port == addr->sin_port)
228 			goto found;
229 	}
230 
231 	return NULL;
232 
233 found:
234 	atomic_inc(&clp->cl_count);
235 	return clp;
236 }
237 
238 /*
239  * Find a client by IP address and protocol version
240  * - returns NULL if no such client
241  */
242 struct nfs_client *nfs_find_client(const struct sockaddr_in *addr, int nfsversion)
243 {
244 	struct nfs_client *clp;
245 
246 	spin_lock(&nfs_client_lock);
247 	clp = __nfs_find_client(addr, nfsversion, 0);
248 	spin_unlock(&nfs_client_lock);
249 	if (clp != NULL && clp->cl_cons_state != NFS_CS_READY) {
250 		nfs_put_client(clp);
251 		clp = NULL;
252 	}
253 	return clp;
254 }
255 
256 /*
257  * Look up a client by IP address and protocol version
258  * - creates a new record if one doesn't yet exist
259  */
260 static struct nfs_client *nfs_get_client(const char *hostname,
261 					 const struct sockaddr_in *addr,
262 					 int nfsversion)
263 {
264 	struct nfs_client *clp, *new = NULL;
265 	int error;
266 
267 	dprintk("--> nfs_get_client(%s,"NIPQUAD_FMT":%d,%d)\n",
268 		hostname ?: "", NIPQUAD(addr->sin_addr),
269 		addr->sin_port, nfsversion);
270 
271 	/* see if the client already exists */
272 	do {
273 		spin_lock(&nfs_client_lock);
274 
275 		clp = __nfs_find_client(addr, nfsversion, 1);
276 		if (clp)
277 			goto found_client;
278 		if (new)
279 			goto install_client;
280 
281 		spin_unlock(&nfs_client_lock);
282 
283 		new = nfs_alloc_client(hostname, addr, nfsversion);
284 	} while (new);
285 
286 	return ERR_PTR(-ENOMEM);
287 
288 	/* install a new client and return with it unready */
289 install_client:
290 	clp = new;
291 	list_add(&clp->cl_share_link, &nfs_client_list);
292 	spin_unlock(&nfs_client_lock);
293 	dprintk("--> nfs_get_client() = %p [new]\n", clp);
294 	return clp;
295 
296 	/* found an existing client
297 	 * - make sure it's ready before returning
298 	 */
299 found_client:
300 	spin_unlock(&nfs_client_lock);
301 
302 	if (new)
303 		nfs_free_client(new);
304 
305 	error = wait_event_interruptible(nfs_client_active_wq,
306 				clp->cl_cons_state != NFS_CS_INITING);
307 	if (error < 0) {
308 		nfs_put_client(clp);
309 		return ERR_PTR(-ERESTARTSYS);
310 	}
311 
312 	if (clp->cl_cons_state < NFS_CS_READY) {
313 		error = clp->cl_cons_state;
314 		nfs_put_client(clp);
315 		return ERR_PTR(error);
316 	}
317 
318 	BUG_ON(clp->cl_cons_state != NFS_CS_READY);
319 
320 	dprintk("--> nfs_get_client() = %p [share]\n", clp);
321 	return clp;
322 }
323 
324 /*
325  * Mark a server as ready or failed
326  */
327 static void nfs_mark_client_ready(struct nfs_client *clp, int state)
328 {
329 	clp->cl_cons_state = state;
330 	wake_up_all(&nfs_client_active_wq);
331 }
332 
333 /*
334  * Initialise the timeout values for a connection
335  */
336 static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
337 				    unsigned int timeo, unsigned int retrans)
338 {
339 	to->to_initval = timeo * HZ / 10;
340 	to->to_retries = retrans;
341 	if (!to->to_retries)
342 		to->to_retries = 2;
343 
344 	switch (proto) {
345 	case XPRT_TRANSPORT_TCP:
346 	case XPRT_TRANSPORT_RDMA:
347 		if (!to->to_initval)
348 			to->to_initval = 60 * HZ;
349 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
350 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
351 		to->to_increment = to->to_initval;
352 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
353 		to->to_exponential = 0;
354 		break;
355 	case XPRT_TRANSPORT_UDP:
356 	default:
357 		if (!to->to_initval)
358 			to->to_initval = 11 * HZ / 10;
359 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
360 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
361 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
362 		to->to_exponential = 1;
363 		break;
364 	}
365 }
366 
367 /*
368  * Create an RPC client handle
369  */
370 static int nfs_create_rpc_client(struct nfs_client *clp, int proto,
371 						unsigned int timeo,
372 						unsigned int retrans,
373 						rpc_authflavor_t flavor,
374 						int flags)
375 {
376 	struct rpc_timeout	timeparms;
377 	struct rpc_clnt		*clnt = NULL;
378 	struct rpc_create_args args = {
379 		.protocol	= proto,
380 		.address	= (struct sockaddr *)&clp->cl_addr,
381 		.addrsize	= sizeof(clp->cl_addr),
382 		.timeout	= &timeparms,
383 		.servername	= clp->cl_hostname,
384 		.program	= &nfs_program,
385 		.version	= clp->rpc_ops->version,
386 		.authflavor	= flavor,
387 		.flags		= flags,
388 	};
389 
390 	if (!IS_ERR(clp->cl_rpcclient))
391 		return 0;
392 
393 	nfs_init_timeout_values(&timeparms, proto, timeo, retrans);
394 	clp->retrans_timeo = timeparms.to_initval;
395 	clp->retrans_count = timeparms.to_retries;
396 
397 	clnt = rpc_create(&args);
398 	if (IS_ERR(clnt)) {
399 		dprintk("%s: cannot create RPC client. Error = %ld\n",
400 				__FUNCTION__, PTR_ERR(clnt));
401 		return PTR_ERR(clnt);
402 	}
403 
404 	clp->cl_rpcclient = clnt;
405 	return 0;
406 }
407 
408 /*
409  * Version 2 or 3 client destruction
410  */
411 static void nfs_destroy_server(struct nfs_server *server)
412 {
413 	if (!IS_ERR(server->client_acl))
414 		rpc_shutdown_client(server->client_acl);
415 
416 	if (!(server->flags & NFS_MOUNT_NONLM))
417 		lockd_down();	/* release rpc.lockd */
418 }
419 
420 /*
421  * Version 2 or 3 lockd setup
422  */
423 static int nfs_start_lockd(struct nfs_server *server)
424 {
425 	int error = 0;
426 
427 	if (server->nfs_client->cl_nfsversion > 3)
428 		goto out;
429 	if (server->flags & NFS_MOUNT_NONLM)
430 		goto out;
431 	error = lockd_up((server->flags & NFS_MOUNT_TCP) ?
432 			IPPROTO_TCP : IPPROTO_UDP);
433 	if (error < 0)
434 		server->flags |= NFS_MOUNT_NONLM;
435 	else
436 		server->destroy = nfs_destroy_server;
437 out:
438 	return error;
439 }
440 
441 /*
442  * Initialise an NFSv3 ACL client connection
443  */
444 #ifdef CONFIG_NFS_V3_ACL
445 static void nfs_init_server_aclclient(struct nfs_server *server)
446 {
447 	if (server->nfs_client->cl_nfsversion != 3)
448 		goto out_noacl;
449 	if (server->flags & NFS_MOUNT_NOACL)
450 		goto out_noacl;
451 
452 	server->client_acl = rpc_bind_new_program(server->client, &nfsacl_program, 3);
453 	if (IS_ERR(server->client_acl))
454 		goto out_noacl;
455 
456 	/* No errors! Assume that Sun nfsacls are supported */
457 	server->caps |= NFS_CAP_ACLS;
458 	return;
459 
460 out_noacl:
461 	server->caps &= ~NFS_CAP_ACLS;
462 }
463 #else
464 static inline void nfs_init_server_aclclient(struct nfs_server *server)
465 {
466 	server->flags &= ~NFS_MOUNT_NOACL;
467 	server->caps &= ~NFS_CAP_ACLS;
468 }
469 #endif
470 
471 /*
472  * Create a general RPC client
473  */
474 static int nfs_init_server_rpcclient(struct nfs_server *server, rpc_authflavor_t pseudoflavour)
475 {
476 	struct nfs_client *clp = server->nfs_client;
477 
478 	server->client = rpc_clone_client(clp->cl_rpcclient);
479 	if (IS_ERR(server->client)) {
480 		dprintk("%s: couldn't create rpc_client!\n", __FUNCTION__);
481 		return PTR_ERR(server->client);
482 	}
483 
484 	if (pseudoflavour != clp->cl_rpcclient->cl_auth->au_flavor) {
485 		struct rpc_auth *auth;
486 
487 		auth = rpcauth_create(pseudoflavour, server->client);
488 		if (IS_ERR(auth)) {
489 			dprintk("%s: couldn't create credcache!\n", __FUNCTION__);
490 			return PTR_ERR(auth);
491 		}
492 	}
493 	server->client->cl_softrtry = 0;
494 	if (server->flags & NFS_MOUNT_SOFT)
495 		server->client->cl_softrtry = 1;
496 
497 	server->client->cl_intr = 0;
498 	if (server->flags & NFS4_MOUNT_INTR)
499 		server->client->cl_intr = 1;
500 
501 	return 0;
502 }
503 
504 /*
505  * Initialise an NFS2 or NFS3 client
506  */
507 static int nfs_init_client(struct nfs_client *clp,
508 			   const struct nfs_parsed_mount_data *data)
509 {
510 	int error;
511 
512 	if (clp->cl_cons_state == NFS_CS_READY) {
513 		/* the client is already initialised */
514 		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
515 		return 0;
516 	}
517 
518 	/* Check NFS protocol revision and initialize RPC op vector */
519 	clp->rpc_ops = &nfs_v2_clientops;
520 #ifdef CONFIG_NFS_V3
521 	if (clp->cl_nfsversion == 3)
522 		clp->rpc_ops = &nfs_v3_clientops;
523 #endif
524 	/*
525 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
526 	 * - RFC 2623, sec 2.3.2
527 	 */
528 	error = nfs_create_rpc_client(clp, data->nfs_server.protocol,
529 				data->timeo, data->retrans, RPC_AUTH_UNIX, 0);
530 	if (error < 0)
531 		goto error;
532 	nfs_mark_client_ready(clp, NFS_CS_READY);
533 	return 0;
534 
535 error:
536 	nfs_mark_client_ready(clp, error);
537 	dprintk("<-- nfs_init_client() = xerror %d\n", error);
538 	return error;
539 }
540 
541 /*
542  * Create a version 2 or 3 client
543  */
544 static int nfs_init_server(struct nfs_server *server,
545 			   const struct nfs_parsed_mount_data *data)
546 {
547 	struct nfs_client *clp;
548 	int error, nfsvers = 2;
549 
550 	dprintk("--> nfs_init_server()\n");
551 
552 #ifdef CONFIG_NFS_V3
553 	if (data->flags & NFS_MOUNT_VER3)
554 		nfsvers = 3;
555 #endif
556 
557 	/* Allocate or find a client reference we can use */
558 	clp = nfs_get_client(data->nfs_server.hostname,
559 				&data->nfs_server.address, nfsvers);
560 	if (IS_ERR(clp)) {
561 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
562 		return PTR_ERR(clp);
563 	}
564 
565 	error = nfs_init_client(clp, data);
566 	if (error < 0)
567 		goto error;
568 
569 	server->nfs_client = clp;
570 
571 	/* Initialise the client representation from the mount data */
572 	server->flags = data->flags & NFS_MOUNT_FLAGMASK;
573 
574 	if (data->rsize)
575 		server->rsize = nfs_block_size(data->rsize, NULL);
576 	if (data->wsize)
577 		server->wsize = nfs_block_size(data->wsize, NULL);
578 
579 	server->acregmin = data->acregmin * HZ;
580 	server->acregmax = data->acregmax * HZ;
581 	server->acdirmin = data->acdirmin * HZ;
582 	server->acdirmax = data->acdirmax * HZ;
583 
584 	/* Start lockd here, before we might error out */
585 	error = nfs_start_lockd(server);
586 	if (error < 0)
587 		goto error;
588 
589 	error = nfs_init_server_rpcclient(server, data->auth_flavors[0]);
590 	if (error < 0)
591 		goto error;
592 
593 	server->namelen  = data->namlen;
594 	/* Create a client RPC handle for the NFSv3 ACL management interface */
595 	nfs_init_server_aclclient(server);
596 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
597 	return 0;
598 
599 error:
600 	server->nfs_client = NULL;
601 	nfs_put_client(clp);
602 	dprintk("<-- nfs_init_server() = xerror %d\n", error);
603 	return error;
604 }
605 
606 /*
607  * Load up the server record from information gained in an fsinfo record
608  */
609 static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo *fsinfo)
610 {
611 	unsigned long max_rpc_payload;
612 
613 	/* Work out a lot of parameters */
614 	if (server->rsize == 0)
615 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
616 	if (server->wsize == 0)
617 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
618 
619 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
620 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
621 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
622 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
623 
624 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
625 	if (server->rsize > max_rpc_payload)
626 		server->rsize = max_rpc_payload;
627 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
628 		server->rsize = NFS_MAX_FILE_IO_SIZE;
629 	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
630 
631 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
632 
633 	if (server->wsize > max_rpc_payload)
634 		server->wsize = max_rpc_payload;
635 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
636 		server->wsize = NFS_MAX_FILE_IO_SIZE;
637 	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
638 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
639 
640 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
641 	if (server->dtsize > PAGE_CACHE_SIZE)
642 		server->dtsize = PAGE_CACHE_SIZE;
643 	if (server->dtsize > server->rsize)
644 		server->dtsize = server->rsize;
645 
646 	if (server->flags & NFS_MOUNT_NOAC) {
647 		server->acregmin = server->acregmax = 0;
648 		server->acdirmin = server->acdirmax = 0;
649 	}
650 
651 	server->maxfilesize = fsinfo->maxfilesize;
652 
653 	/* We're airborne Set socket buffersize */
654 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
655 }
656 
657 /*
658  * Probe filesystem information, including the FSID on v2/v3
659  */
660 static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
661 {
662 	struct nfs_fsinfo fsinfo;
663 	struct nfs_client *clp = server->nfs_client;
664 	int error;
665 
666 	dprintk("--> nfs_probe_fsinfo()\n");
667 
668 	if (clp->rpc_ops->set_capabilities != NULL) {
669 		error = clp->rpc_ops->set_capabilities(server, mntfh);
670 		if (error < 0)
671 			goto out_error;
672 	}
673 
674 	fsinfo.fattr = fattr;
675 	nfs_fattr_init(fattr);
676 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
677 	if (error < 0)
678 		goto out_error;
679 
680 	nfs_server_set_fsinfo(server, &fsinfo);
681 	error = bdi_init(&server->backing_dev_info);
682 	if (error)
683 		goto out_error;
684 
685 
686 	/* Get some general file system info */
687 	if (server->namelen == 0) {
688 		struct nfs_pathconf pathinfo;
689 
690 		pathinfo.fattr = fattr;
691 		nfs_fattr_init(fattr);
692 
693 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
694 			server->namelen = pathinfo.max_namelen;
695 	}
696 
697 	dprintk("<-- nfs_probe_fsinfo() = 0\n");
698 	return 0;
699 
700 out_error:
701 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
702 	return error;
703 }
704 
705 /*
706  * Copy useful information when duplicating a server record
707  */
708 static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
709 {
710 	target->flags = source->flags;
711 	target->acregmin = source->acregmin;
712 	target->acregmax = source->acregmax;
713 	target->acdirmin = source->acdirmin;
714 	target->acdirmax = source->acdirmax;
715 	target->caps = source->caps;
716 }
717 
718 /*
719  * Allocate and initialise a server record
720  */
721 static struct nfs_server *nfs_alloc_server(void)
722 {
723 	struct nfs_server *server;
724 
725 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
726 	if (!server)
727 		return NULL;
728 
729 	server->client = server->client_acl = ERR_PTR(-EINVAL);
730 
731 	/* Zero out the NFS state stuff */
732 	INIT_LIST_HEAD(&server->client_link);
733 	INIT_LIST_HEAD(&server->master_link);
734 
735 	server->io_stats = nfs_alloc_iostats();
736 	if (!server->io_stats) {
737 		kfree(server);
738 		return NULL;
739 	}
740 
741 	return server;
742 }
743 
744 /*
745  * Free up a server record
746  */
747 void nfs_free_server(struct nfs_server *server)
748 {
749 	dprintk("--> nfs_free_server()\n");
750 
751 	spin_lock(&nfs_client_lock);
752 	list_del(&server->client_link);
753 	list_del(&server->master_link);
754 	spin_unlock(&nfs_client_lock);
755 
756 	if (server->destroy != NULL)
757 		server->destroy(server);
758 	if (!IS_ERR(server->client))
759 		rpc_shutdown_client(server->client);
760 
761 	nfs_put_client(server->nfs_client);
762 
763 	nfs_free_iostats(server->io_stats);
764 	bdi_destroy(&server->backing_dev_info);
765 	kfree(server);
766 	nfs_release_automount_timer();
767 	dprintk("<-- nfs_free_server()\n");
768 }
769 
770 /*
771  * Create a version 2 or 3 volume record
772  * - keyed on server and FSID
773  */
774 struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
775 				     struct nfs_fh *mntfh)
776 {
777 	struct nfs_server *server;
778 	struct nfs_fattr fattr;
779 	int error;
780 
781 	server = nfs_alloc_server();
782 	if (!server)
783 		return ERR_PTR(-ENOMEM);
784 
785 	/* Get a client representation */
786 	error = nfs_init_server(server, data);
787 	if (error < 0)
788 		goto error;
789 
790 	BUG_ON(!server->nfs_client);
791 	BUG_ON(!server->nfs_client->rpc_ops);
792 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
793 
794 	/* Probe the root fh to retrieve its FSID */
795 	error = nfs_probe_fsinfo(server, mntfh, &fattr);
796 	if (error < 0)
797 		goto error;
798 	if (server->nfs_client->rpc_ops->version == 3) {
799 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
800 			server->namelen = NFS3_MAXNAMLEN;
801 		if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
802 			server->caps |= NFS_CAP_READDIRPLUS;
803 	} else {
804 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
805 			server->namelen = NFS2_MAXNAMLEN;
806 	}
807 
808 	if (!(fattr.valid & NFS_ATTR_FATTR)) {
809 		error = server->nfs_client->rpc_ops->getattr(server, mntfh, &fattr);
810 		if (error < 0) {
811 			dprintk("nfs_create_server: getattr error = %d\n", -error);
812 			goto error;
813 		}
814 	}
815 	memcpy(&server->fsid, &fattr.fsid, sizeof(server->fsid));
816 
817 	dprintk("Server FSID: %llx:%llx\n",
818 		(unsigned long long) server->fsid.major,
819 		(unsigned long long) server->fsid.minor);
820 
821 	BUG_ON(!server->nfs_client);
822 	BUG_ON(!server->nfs_client->rpc_ops);
823 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
824 
825 	spin_lock(&nfs_client_lock);
826 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
827 	list_add_tail(&server->master_link, &nfs_volume_list);
828 	spin_unlock(&nfs_client_lock);
829 
830 	server->mount_time = jiffies;
831 	return server;
832 
833 error:
834 	nfs_free_server(server);
835 	return ERR_PTR(error);
836 }
837 
838 #ifdef CONFIG_NFS_V4
839 /*
840  * Initialise an NFS4 client record
841  */
842 static int nfs4_init_client(struct nfs_client *clp,
843 		int proto, int timeo, int retrans,
844 		const char *ip_addr,
845 		rpc_authflavor_t authflavour)
846 {
847 	int error;
848 
849 	if (clp->cl_cons_state == NFS_CS_READY) {
850 		/* the client is initialised already */
851 		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
852 		return 0;
853 	}
854 
855 	/* Check NFS protocol revision and initialize RPC op vector */
856 	clp->rpc_ops = &nfs_v4_clientops;
857 
858 	error = nfs_create_rpc_client(clp, proto, timeo, retrans, authflavour,
859 					RPC_CLNT_CREATE_DISCRTRY);
860 	if (error < 0)
861 		goto error;
862 	memcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
863 
864 	error = nfs_idmap_new(clp);
865 	if (error < 0) {
866 		dprintk("%s: failed to create idmapper. Error = %d\n",
867 			__FUNCTION__, error);
868 		goto error;
869 	}
870 	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
871 
872 	nfs_mark_client_ready(clp, NFS_CS_READY);
873 	return 0;
874 
875 error:
876 	nfs_mark_client_ready(clp, error);
877 	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
878 	return error;
879 }
880 
881 /*
882  * Set up an NFS4 client
883  */
884 static int nfs4_set_client(struct nfs_server *server,
885 		const char *hostname, const struct sockaddr_in *addr,
886 		const char *ip_addr,
887 		rpc_authflavor_t authflavour,
888 		int proto, int timeo, int retrans)
889 {
890 	struct nfs_client *clp;
891 	int error;
892 
893 	dprintk("--> nfs4_set_client()\n");
894 
895 	/* Allocate or find a client reference we can use */
896 	clp = nfs_get_client(hostname, addr, 4);
897 	if (IS_ERR(clp)) {
898 		error = PTR_ERR(clp);
899 		goto error;
900 	}
901 	error = nfs4_init_client(clp, proto, timeo, retrans, ip_addr, authflavour);
902 	if (error < 0)
903 		goto error_put;
904 
905 	server->nfs_client = clp;
906 	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
907 	return 0;
908 
909 error_put:
910 	nfs_put_client(clp);
911 error:
912 	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
913 	return error;
914 }
915 
916 /*
917  * Create a version 4 volume record
918  */
919 static int nfs4_init_server(struct nfs_server *server,
920 		const struct nfs_parsed_mount_data *data)
921 {
922 	int error;
923 
924 	dprintk("--> nfs4_init_server()\n");
925 
926 	/* Initialise the client representation from the mount data */
927 	server->flags = data->flags & NFS_MOUNT_FLAGMASK;
928 	server->caps |= NFS_CAP_ATOMIC_OPEN;
929 
930 	if (data->rsize)
931 		server->rsize = nfs_block_size(data->rsize, NULL);
932 	if (data->wsize)
933 		server->wsize = nfs_block_size(data->wsize, NULL);
934 
935 	server->acregmin = data->acregmin * HZ;
936 	server->acregmax = data->acregmax * HZ;
937 	server->acdirmin = data->acdirmin * HZ;
938 	server->acdirmax = data->acdirmax * HZ;
939 
940 	error = nfs_init_server_rpcclient(server, data->auth_flavors[0]);
941 
942 	/* Done */
943 	dprintk("<-- nfs4_init_server() = %d\n", error);
944 	return error;
945 }
946 
947 /*
948  * Create a version 4 volume record
949  * - keyed on server and FSID
950  */
951 struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
952 				      struct nfs_fh *mntfh)
953 {
954 	struct nfs_fattr fattr;
955 	struct nfs_server *server;
956 	int error;
957 
958 	dprintk("--> nfs4_create_server()\n");
959 
960 	server = nfs_alloc_server();
961 	if (!server)
962 		return ERR_PTR(-ENOMEM);
963 
964 	/* Get a client record */
965 	error = nfs4_set_client(server,
966 			data->nfs_server.hostname,
967 			&data->nfs_server.address,
968 			data->client_address,
969 			data->auth_flavors[0],
970 			data->nfs_server.protocol,
971 			data->timeo, data->retrans);
972 	if (error < 0)
973 		goto error;
974 
975 	/* set up the general RPC client */
976 	error = nfs4_init_server(server, data);
977 	if (error < 0)
978 		goto error;
979 
980 	BUG_ON(!server->nfs_client);
981 	BUG_ON(!server->nfs_client->rpc_ops);
982 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
983 
984 	/* Probe the root fh to retrieve its FSID */
985 	error = nfs4_path_walk(server, mntfh, data->nfs_server.export_path);
986 	if (error < 0)
987 		goto error;
988 
989 	dprintk("Server FSID: %llx:%llx\n",
990 		(unsigned long long) server->fsid.major,
991 		(unsigned long long) server->fsid.minor);
992 	dprintk("Mount FH: %d\n", mntfh->size);
993 
994 	error = nfs_probe_fsinfo(server, mntfh, &fattr);
995 	if (error < 0)
996 		goto error;
997 
998 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
999 		server->namelen = NFS4_MAXNAMLEN;
1000 
1001 	BUG_ON(!server->nfs_client);
1002 	BUG_ON(!server->nfs_client->rpc_ops);
1003 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1004 
1005 	spin_lock(&nfs_client_lock);
1006 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1007 	list_add_tail(&server->master_link, &nfs_volume_list);
1008 	spin_unlock(&nfs_client_lock);
1009 
1010 	server->mount_time = jiffies;
1011 	dprintk("<-- nfs4_create_server() = %p\n", server);
1012 	return server;
1013 
1014 error:
1015 	nfs_free_server(server);
1016 	dprintk("<-- nfs4_create_server() = error %d\n", error);
1017 	return ERR_PTR(error);
1018 }
1019 
1020 /*
1021  * Create an NFS4 referral server record
1022  */
1023 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1024 					       struct nfs_fh *mntfh)
1025 {
1026 	struct nfs_client *parent_client;
1027 	struct nfs_server *server, *parent_server;
1028 	struct nfs_fattr fattr;
1029 	int error;
1030 
1031 	dprintk("--> nfs4_create_referral_server()\n");
1032 
1033 	server = nfs_alloc_server();
1034 	if (!server)
1035 		return ERR_PTR(-ENOMEM);
1036 
1037 	parent_server = NFS_SB(data->sb);
1038 	parent_client = parent_server->nfs_client;
1039 
1040 	/* Get a client representation.
1041 	 * Note: NFSv4 always uses TCP, */
1042 	error = nfs4_set_client(server, data->hostname, data->addr,
1043 			parent_client->cl_ipaddr,
1044 			data->authflavor,
1045 			parent_server->client->cl_xprt->prot,
1046 			parent_client->retrans_timeo,
1047 			parent_client->retrans_count);
1048 	if (error < 0)
1049 		goto error;
1050 
1051 	/* Initialise the client representation from the parent server */
1052 	nfs_server_copy_userdata(server, parent_server);
1053 	server->caps |= NFS_CAP_ATOMIC_OPEN;
1054 
1055 	error = nfs_init_server_rpcclient(server, data->authflavor);
1056 	if (error < 0)
1057 		goto error;
1058 
1059 	BUG_ON(!server->nfs_client);
1060 	BUG_ON(!server->nfs_client->rpc_ops);
1061 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1062 
1063 	/* Probe the root fh to retrieve its FSID and filehandle */
1064 	error = nfs4_path_walk(server, mntfh, data->mnt_path);
1065 	if (error < 0)
1066 		goto error;
1067 
1068 	/* probe the filesystem info for this server filesystem */
1069 	error = nfs_probe_fsinfo(server, mntfh, &fattr);
1070 	if (error < 0)
1071 		goto error;
1072 
1073 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1074 		server->namelen = NFS4_MAXNAMLEN;
1075 
1076 	dprintk("Referral FSID: %llx:%llx\n",
1077 		(unsigned long long) server->fsid.major,
1078 		(unsigned long long) server->fsid.minor);
1079 
1080 	spin_lock(&nfs_client_lock);
1081 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1082 	list_add_tail(&server->master_link, &nfs_volume_list);
1083 	spin_unlock(&nfs_client_lock);
1084 
1085 	server->mount_time = jiffies;
1086 
1087 	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1088 	return server;
1089 
1090 error:
1091 	nfs_free_server(server);
1092 	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1093 	return ERR_PTR(error);
1094 }
1095 
1096 #endif /* CONFIG_NFS_V4 */
1097 
1098 /*
1099  * Clone an NFS2, NFS3 or NFS4 server record
1100  */
1101 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1102 				    struct nfs_fh *fh,
1103 				    struct nfs_fattr *fattr)
1104 {
1105 	struct nfs_server *server;
1106 	struct nfs_fattr fattr_fsinfo;
1107 	int error;
1108 
1109 	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1110 		(unsigned long long) fattr->fsid.major,
1111 		(unsigned long long) fattr->fsid.minor);
1112 
1113 	server = nfs_alloc_server();
1114 	if (!server)
1115 		return ERR_PTR(-ENOMEM);
1116 
1117 	/* Copy data from the source */
1118 	server->nfs_client = source->nfs_client;
1119 	atomic_inc(&server->nfs_client->cl_count);
1120 	nfs_server_copy_userdata(server, source);
1121 
1122 	server->fsid = fattr->fsid;
1123 
1124 	error = nfs_init_server_rpcclient(server, source->client->cl_auth->au_flavor);
1125 	if (error < 0)
1126 		goto out_free_server;
1127 	if (!IS_ERR(source->client_acl))
1128 		nfs_init_server_aclclient(server);
1129 
1130 	/* probe the filesystem info for this server filesystem */
1131 	error = nfs_probe_fsinfo(server, fh, &fattr_fsinfo);
1132 	if (error < 0)
1133 		goto out_free_server;
1134 
1135 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1136 		server->namelen = NFS4_MAXNAMLEN;
1137 
1138 	dprintk("Cloned FSID: %llx:%llx\n",
1139 		(unsigned long long) server->fsid.major,
1140 		(unsigned long long) server->fsid.minor);
1141 
1142 	error = nfs_start_lockd(server);
1143 	if (error < 0)
1144 		goto out_free_server;
1145 
1146 	spin_lock(&nfs_client_lock);
1147 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1148 	list_add_tail(&server->master_link, &nfs_volume_list);
1149 	spin_unlock(&nfs_client_lock);
1150 
1151 	server->mount_time = jiffies;
1152 
1153 	dprintk("<-- nfs_clone_server() = %p\n", server);
1154 	return server;
1155 
1156 out_free_server:
1157 	nfs_free_server(server);
1158 	dprintk("<-- nfs_clone_server() = error %d\n", error);
1159 	return ERR_PTR(error);
1160 }
1161 
1162 #ifdef CONFIG_PROC_FS
1163 static struct proc_dir_entry *proc_fs_nfs;
1164 
1165 static int nfs_server_list_open(struct inode *inode, struct file *file);
1166 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1167 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1168 static void nfs_server_list_stop(struct seq_file *p, void *v);
1169 static int nfs_server_list_show(struct seq_file *m, void *v);
1170 
1171 static struct seq_operations nfs_server_list_ops = {
1172 	.start	= nfs_server_list_start,
1173 	.next	= nfs_server_list_next,
1174 	.stop	= nfs_server_list_stop,
1175 	.show	= nfs_server_list_show,
1176 };
1177 
1178 static const struct file_operations nfs_server_list_fops = {
1179 	.open		= nfs_server_list_open,
1180 	.read		= seq_read,
1181 	.llseek		= seq_lseek,
1182 	.release	= seq_release,
1183 };
1184 
1185 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1186 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1187 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1188 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1189 static int nfs_volume_list_show(struct seq_file *m, void *v);
1190 
1191 static struct seq_operations nfs_volume_list_ops = {
1192 	.start	= nfs_volume_list_start,
1193 	.next	= nfs_volume_list_next,
1194 	.stop	= nfs_volume_list_stop,
1195 	.show	= nfs_volume_list_show,
1196 };
1197 
1198 static const struct file_operations nfs_volume_list_fops = {
1199 	.open		= nfs_volume_list_open,
1200 	.read		= seq_read,
1201 	.llseek		= seq_lseek,
1202 	.release	= seq_release,
1203 };
1204 
1205 /*
1206  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1207  * we're dealing
1208  */
1209 static int nfs_server_list_open(struct inode *inode, struct file *file)
1210 {
1211 	struct seq_file *m;
1212 	int ret;
1213 
1214 	ret = seq_open(file, &nfs_server_list_ops);
1215 	if (ret < 0)
1216 		return ret;
1217 
1218 	m = file->private_data;
1219 	m->private = PDE(inode)->data;
1220 
1221 	return 0;
1222 }
1223 
1224 /*
1225  * set up the iterator to start reading from the server list and return the first item
1226  */
1227 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1228 {
1229 	/* lock the list against modification */
1230 	spin_lock(&nfs_client_lock);
1231 	return seq_list_start_head(&nfs_client_list, *_pos);
1232 }
1233 
1234 /*
1235  * move to next server
1236  */
1237 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1238 {
1239 	return seq_list_next(v, &nfs_client_list, pos);
1240 }
1241 
1242 /*
1243  * clean up after reading from the transports list
1244  */
1245 static void nfs_server_list_stop(struct seq_file *p, void *v)
1246 {
1247 	spin_unlock(&nfs_client_lock);
1248 }
1249 
1250 /*
1251  * display a header line followed by a load of call lines
1252  */
1253 static int nfs_server_list_show(struct seq_file *m, void *v)
1254 {
1255 	struct nfs_client *clp;
1256 
1257 	/* display header on line 1 */
1258 	if (v == &nfs_client_list) {
1259 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1260 		return 0;
1261 	}
1262 
1263 	/* display one transport per line on subsequent lines */
1264 	clp = list_entry(v, struct nfs_client, cl_share_link);
1265 
1266 	seq_printf(m, "v%d %02x%02x%02x%02x %4hx %3d %s\n",
1267 		   clp->cl_nfsversion,
1268 		   NIPQUAD(clp->cl_addr.sin_addr),
1269 		   ntohs(clp->cl_addr.sin_port),
1270 		   atomic_read(&clp->cl_count),
1271 		   clp->cl_hostname);
1272 
1273 	return 0;
1274 }
1275 
1276 /*
1277  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1278  */
1279 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1280 {
1281 	struct seq_file *m;
1282 	int ret;
1283 
1284 	ret = seq_open(file, &nfs_volume_list_ops);
1285 	if (ret < 0)
1286 		return ret;
1287 
1288 	m = file->private_data;
1289 	m->private = PDE(inode)->data;
1290 
1291 	return 0;
1292 }
1293 
1294 /*
1295  * set up the iterator to start reading from the volume list and return the first item
1296  */
1297 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1298 {
1299 	/* lock the list against modification */
1300 	spin_lock(&nfs_client_lock);
1301 	return seq_list_start_head(&nfs_volume_list, *_pos);
1302 }
1303 
1304 /*
1305  * move to next volume
1306  */
1307 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1308 {
1309 	return seq_list_next(v, &nfs_volume_list, pos);
1310 }
1311 
1312 /*
1313  * clean up after reading from the transports list
1314  */
1315 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1316 {
1317 	spin_unlock(&nfs_client_lock);
1318 }
1319 
1320 /*
1321  * display a header line followed by a load of call lines
1322  */
1323 static int nfs_volume_list_show(struct seq_file *m, void *v)
1324 {
1325 	struct nfs_server *server;
1326 	struct nfs_client *clp;
1327 	char dev[8], fsid[17];
1328 
1329 	/* display header on line 1 */
1330 	if (v == &nfs_volume_list) {
1331 		seq_puts(m, "NV SERVER   PORT DEV     FSID\n");
1332 		return 0;
1333 	}
1334 	/* display one transport per line on subsequent lines */
1335 	server = list_entry(v, struct nfs_server, master_link);
1336 	clp = server->nfs_client;
1337 
1338 	snprintf(dev, 8, "%u:%u",
1339 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1340 
1341 	snprintf(fsid, 17, "%llx:%llx",
1342 		 (unsigned long long) server->fsid.major,
1343 		 (unsigned long long) server->fsid.minor);
1344 
1345 	seq_printf(m, "v%d %02x%02x%02x%02x %4hx %-7s %-17s\n",
1346 		   clp->cl_nfsversion,
1347 		   NIPQUAD(clp->cl_addr.sin_addr),
1348 		   ntohs(clp->cl_addr.sin_port),
1349 		   dev,
1350 		   fsid);
1351 
1352 	return 0;
1353 }
1354 
1355 /*
1356  * initialise the /proc/fs/nfsfs/ directory
1357  */
1358 int __init nfs_fs_proc_init(void)
1359 {
1360 	struct proc_dir_entry *p;
1361 
1362 	proc_fs_nfs = proc_mkdir("nfsfs", proc_root_fs);
1363 	if (!proc_fs_nfs)
1364 		goto error_0;
1365 
1366 	proc_fs_nfs->owner = THIS_MODULE;
1367 
1368 	/* a file of servers with which we're dealing */
1369 	p = create_proc_entry("servers", S_IFREG|S_IRUGO, proc_fs_nfs);
1370 	if (!p)
1371 		goto error_1;
1372 
1373 	p->proc_fops = &nfs_server_list_fops;
1374 	p->owner = THIS_MODULE;
1375 
1376 	/* a file of volumes that we have mounted */
1377 	p = create_proc_entry("volumes", S_IFREG|S_IRUGO, proc_fs_nfs);
1378 	if (!p)
1379 		goto error_2;
1380 
1381 	p->proc_fops = &nfs_volume_list_fops;
1382 	p->owner = THIS_MODULE;
1383 	return 0;
1384 
1385 error_2:
1386 	remove_proc_entry("servers", proc_fs_nfs);
1387 error_1:
1388 	remove_proc_entry("nfsfs", proc_root_fs);
1389 error_0:
1390 	return -ENOMEM;
1391 }
1392 
1393 /*
1394  * clean up the /proc/fs/nfsfs/ directory
1395  */
1396 void nfs_fs_proc_exit(void)
1397 {
1398 	remove_proc_entry("volumes", proc_fs_nfs);
1399 	remove_proc_entry("servers", proc_fs_nfs);
1400 	remove_proc_entry("nfsfs", proc_root_fs);
1401 }
1402 
1403 #endif /* CONFIG_PROC_FS */
1404