xref: /openbmc/linux/fs/nfs/client.c (revision a613fa168afc19179a7547fbba45644c5b6912bf)
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/in6.h>
38 #include <linux/slab.h>
39 #include <net/ipv6.h>
40 #include <linux/nfs_xdr.h>
41 #include <linux/sunrpc/bc_xprt.h>
42 
43 #include <asm/system.h>
44 
45 #include "nfs4_fs.h"
46 #include "callback.h"
47 #include "delegation.h"
48 #include "iostat.h"
49 #include "internal.h"
50 #include "fscache.h"
51 #include "pnfs.h"
52 
53 #define NFSDBG_FACILITY		NFSDBG_CLIENT
54 
55 DEFINE_SPINLOCK(nfs_client_lock);
56 LIST_HEAD(nfs_client_list);
57 static LIST_HEAD(nfs_volume_list);
58 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
59 #ifdef CONFIG_NFS_V4
60 static DEFINE_IDR(cb_ident_idr); /* Protected by nfs_client_lock */
61 
62 /*
63  * Get a unique NFSv4.0 callback identifier which will be used
64  * by the V4.0 callback service to lookup the nfs_client struct
65  */
66 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
67 {
68 	int ret = 0;
69 
70 	if (clp->rpc_ops->version != 4 || minorversion != 0)
71 		return ret;
72 retry:
73 	if (!idr_pre_get(&cb_ident_idr, GFP_KERNEL))
74 		return -ENOMEM;
75 	spin_lock(&nfs_client_lock);
76 	ret = idr_get_new(&cb_ident_idr, clp, &clp->cl_cb_ident);
77 	spin_unlock(&nfs_client_lock);
78 	if (ret == -EAGAIN)
79 		goto retry;
80 	return ret;
81 }
82 #endif /* CONFIG_NFS_V4 */
83 
84 /*
85  * Turn off NFSv4 uid/gid mapping when using AUTH_SYS
86  */
87 static bool nfs4_disable_idmapping = true;
88 
89 /*
90  * RPC cruft for NFS
91  */
92 static const struct rpc_version *nfs_version[5] = {
93 	[2]			= &nfs_version2,
94 #ifdef CONFIG_NFS_V3
95 	[3]			= &nfs_version3,
96 #endif
97 #ifdef CONFIG_NFS_V4
98 	[4]			= &nfs_version4,
99 #endif
100 };
101 
102 const struct rpc_program nfs_program = {
103 	.name			= "nfs",
104 	.number			= NFS_PROGRAM,
105 	.nrvers			= ARRAY_SIZE(nfs_version),
106 	.version		= nfs_version,
107 	.stats			= &nfs_rpcstat,
108 	.pipe_dir_name		= NFS_PIPE_DIRNAME,
109 };
110 
111 struct rpc_stat nfs_rpcstat = {
112 	.program		= &nfs_program
113 };
114 
115 
116 #ifdef CONFIG_NFS_V3_ACL
117 static struct rpc_stat		nfsacl_rpcstat = { &nfsacl_program };
118 static const struct rpc_version *nfsacl_version[] = {
119 	[3]			= &nfsacl_version3,
120 };
121 
122 const struct rpc_program nfsacl_program = {
123 	.name			= "nfsacl",
124 	.number			= NFS_ACL_PROGRAM,
125 	.nrvers			= ARRAY_SIZE(nfsacl_version),
126 	.version		= nfsacl_version,
127 	.stats			= &nfsacl_rpcstat,
128 };
129 #endif  /* CONFIG_NFS_V3_ACL */
130 
131 struct nfs_client_initdata {
132 	const char *hostname;
133 	const struct sockaddr *addr;
134 	size_t addrlen;
135 	const struct nfs_rpc_ops *rpc_ops;
136 	int proto;
137 	u32 minorversion;
138 	struct net *net;
139 };
140 
141 /*
142  * Allocate a shared client record
143  *
144  * Since these are allocated/deallocated very rarely, we don't
145  * bother putting them in a slab cache...
146  */
147 static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
148 {
149 	struct nfs_client *clp;
150 	struct rpc_cred *cred;
151 	int err = -ENOMEM;
152 
153 	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
154 		goto error_0;
155 
156 	clp->rpc_ops = cl_init->rpc_ops;
157 
158 	atomic_set(&clp->cl_count, 1);
159 	clp->cl_cons_state = NFS_CS_INITING;
160 
161 	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
162 	clp->cl_addrlen = cl_init->addrlen;
163 
164 	if (cl_init->hostname) {
165 		err = -ENOMEM;
166 		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
167 		if (!clp->cl_hostname)
168 			goto error_cleanup;
169 	}
170 
171 	INIT_LIST_HEAD(&clp->cl_superblocks);
172 	clp->cl_rpcclient = ERR_PTR(-EINVAL);
173 
174 	clp->cl_proto = cl_init->proto;
175 
176 #ifdef CONFIG_NFS_V4
177 	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
178 	if (err)
179 		goto error_cleanup;
180 
181 	spin_lock_init(&clp->cl_lock);
182 	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
183 	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
184 	clp->cl_boot_time = CURRENT_TIME;
185 	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
186 	clp->cl_minorversion = cl_init->minorversion;
187 	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
188 #endif
189 	cred = rpc_lookup_machine_cred("*");
190 	if (!IS_ERR(cred))
191 		clp->cl_machine_cred = cred;
192 	nfs_fscache_get_client_cookie(clp);
193 	clp->net = cl_init->net;
194 
195 	return clp;
196 
197 error_cleanup:
198 	kfree(clp);
199 error_0:
200 	return ERR_PTR(err);
201 }
202 
203 #ifdef CONFIG_NFS_V4
204 #ifdef CONFIG_NFS_V4_1
205 static void nfs4_shutdown_session(struct nfs_client *clp)
206 {
207 	if (nfs4_has_session(clp))
208 		nfs4_destroy_session(clp->cl_session);
209 }
210 #else /* CONFIG_NFS_V4_1 */
211 static void nfs4_shutdown_session(struct nfs_client *clp)
212 {
213 }
214 #endif /* CONFIG_NFS_V4_1 */
215 
216 /*
217  * Destroy the NFS4 callback service
218  */
219 static void nfs4_destroy_callback(struct nfs_client *clp)
220 {
221 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
222 		nfs_callback_down(clp->cl_mvops->minor_version);
223 }
224 
225 static void nfs4_shutdown_client(struct nfs_client *clp)
226 {
227 	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
228 		nfs4_kill_renewd(clp);
229 	nfs4_shutdown_session(clp);
230 	nfs4_destroy_callback(clp);
231 	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
232 		nfs_idmap_delete(clp);
233 
234 	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
235 }
236 
237 /* idr_remove_all is not needed as all id's are removed by nfs_put_client */
238 void nfs_cleanup_cb_ident_idr(void)
239 {
240 	idr_destroy(&cb_ident_idr);
241 }
242 
243 /* nfs_client_lock held */
244 static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
245 {
246 	if (clp->cl_cb_ident)
247 		idr_remove(&cb_ident_idr, clp->cl_cb_ident);
248 }
249 
250 static void pnfs_init_server(struct nfs_server *server)
251 {
252 	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
253 }
254 
255 static void nfs4_destroy_server(struct nfs_server *server)
256 {
257 	nfs4_purge_state_owners(server);
258 }
259 
260 #else
261 static void nfs4_shutdown_client(struct nfs_client *clp)
262 {
263 }
264 
265 void nfs_cleanup_cb_ident_idr(void)
266 {
267 }
268 
269 static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
270 {
271 }
272 
273 static void pnfs_init_server(struct nfs_server *server)
274 {
275 }
276 
277 #endif /* CONFIG_NFS_V4 */
278 
279 /*
280  * Destroy a shared client record
281  */
282 static void nfs_free_client(struct nfs_client *clp)
283 {
284 	dprintk("--> nfs_free_client(%u)\n", clp->rpc_ops->version);
285 
286 	nfs4_shutdown_client(clp);
287 
288 	nfs_fscache_release_client_cookie(clp);
289 
290 	/* -EIO all pending I/O */
291 	if (!IS_ERR(clp->cl_rpcclient))
292 		rpc_shutdown_client(clp->cl_rpcclient);
293 
294 	if (clp->cl_machine_cred != NULL)
295 		put_rpccred(clp->cl_machine_cred);
296 
297 	nfs4_deviceid_purge_client(clp);
298 
299 	kfree(clp->cl_hostname);
300 	kfree(clp->server_scope);
301 	kfree(clp);
302 
303 	dprintk("<-- nfs_free_client()\n");
304 }
305 
306 /*
307  * Release a reference to a shared client record
308  */
309 void nfs_put_client(struct nfs_client *clp)
310 {
311 	if (!clp)
312 		return;
313 
314 	dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
315 
316 	if (atomic_dec_and_lock(&clp->cl_count, &nfs_client_lock)) {
317 		list_del(&clp->cl_share_link);
318 		nfs_cb_idr_remove_locked(clp);
319 		spin_unlock(&nfs_client_lock);
320 
321 		BUG_ON(!list_empty(&clp->cl_superblocks));
322 
323 		nfs_free_client(clp);
324 	}
325 }
326 EXPORT_SYMBOL_GPL(nfs_put_client);
327 
328 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
329 /*
330  * Test if two ip6 socket addresses refer to the same socket by
331  * comparing relevant fields. The padding bytes specifically, are not
332  * compared. sin6_flowinfo is not compared because it only affects QoS
333  * and sin6_scope_id is only compared if the address is "link local"
334  * because "link local" addresses need only be unique to a specific
335  * link. Conversely, ordinary unicast addresses might have different
336  * sin6_scope_id.
337  *
338  * The caller should ensure both socket addresses are AF_INET6.
339  */
340 static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
341 				      const struct sockaddr *sa2)
342 {
343 	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
344 	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
345 
346 	if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
347 		return 0;
348 	else if (ipv6_addr_type(&sin1->sin6_addr) & IPV6_ADDR_LINKLOCAL)
349 		return sin1->sin6_scope_id == sin2->sin6_scope_id;
350 
351 	return 1;
352 }
353 #else	/* !defined(CONFIG_IPV6) && !defined(CONFIG_IPV6_MODULE) */
354 static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
355 				      const struct sockaddr *sa2)
356 {
357 	return 0;
358 }
359 #endif
360 
361 /*
362  * Test if two ip4 socket addresses refer to the same socket, by
363  * comparing relevant fields. The padding bytes specifically, are
364  * not compared.
365  *
366  * The caller should ensure both socket addresses are AF_INET.
367  */
368 static int nfs_sockaddr_match_ipaddr4(const struct sockaddr *sa1,
369 				      const struct sockaddr *sa2)
370 {
371 	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
372 	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
373 
374 	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
375 }
376 
377 static int nfs_sockaddr_cmp_ip6(const struct sockaddr *sa1,
378 				const struct sockaddr *sa2)
379 {
380 	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
381 	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
382 
383 	return nfs_sockaddr_match_ipaddr6(sa1, sa2) &&
384 		(sin1->sin6_port == sin2->sin6_port);
385 }
386 
387 static int nfs_sockaddr_cmp_ip4(const struct sockaddr *sa1,
388 				const struct sockaddr *sa2)
389 {
390 	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
391 	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
392 
393 	return nfs_sockaddr_match_ipaddr4(sa1, sa2) &&
394 		(sin1->sin_port == sin2->sin_port);
395 }
396 
397 /*
398  * Test if two socket addresses represent the same actual socket,
399  * by comparing (only) relevant fields, excluding the port number.
400  */
401 static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
402 				     const struct sockaddr *sa2)
403 {
404 	if (sa1->sa_family != sa2->sa_family)
405 		return 0;
406 
407 	switch (sa1->sa_family) {
408 	case AF_INET:
409 		return nfs_sockaddr_match_ipaddr4(sa1, sa2);
410 	case AF_INET6:
411 		return nfs_sockaddr_match_ipaddr6(sa1, sa2);
412 	}
413 	return 0;
414 }
415 
416 /*
417  * Test if two socket addresses represent the same actual socket,
418  * by comparing (only) relevant fields, including the port number.
419  */
420 static int nfs_sockaddr_cmp(const struct sockaddr *sa1,
421 			    const struct sockaddr *sa2)
422 {
423 	if (sa1->sa_family != sa2->sa_family)
424 		return 0;
425 
426 	switch (sa1->sa_family) {
427 	case AF_INET:
428 		return nfs_sockaddr_cmp_ip4(sa1, sa2);
429 	case AF_INET6:
430 		return nfs_sockaddr_cmp_ip6(sa1, sa2);
431 	}
432 	return 0;
433 }
434 
435 /* Common match routine for v4.0 and v4.1 callback services */
436 bool
437 nfs4_cb_match_client(const struct sockaddr *addr, struct nfs_client *clp,
438 		     u32 minorversion)
439 {
440 	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
441 
442 	/* Don't match clients that failed to initialise */
443 	if (!(clp->cl_cons_state == NFS_CS_READY ||
444 	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
445 		return false;
446 
447 	/* Match the version and minorversion */
448 	if (clp->rpc_ops->version != 4 ||
449 	    clp->cl_minorversion != minorversion)
450 		return false;
451 
452 	/* Match only the IP address, not the port number */
453 	if (!nfs_sockaddr_match_ipaddr(addr, clap))
454 		return false;
455 
456 	return true;
457 }
458 
459 /*
460  * Find an nfs_client on the list that matches the initialisation data
461  * that is supplied.
462  */
463 static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
464 {
465 	struct nfs_client *clp;
466 	const struct sockaddr *sap = data->addr;
467 
468 	list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
469 	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
470 		/* Don't match clients that failed to initialise properly */
471 		if (clp->cl_cons_state < 0)
472 			continue;
473 
474 		/* Different NFS versions cannot share the same nfs_client */
475 		if (clp->rpc_ops != data->rpc_ops)
476 			continue;
477 
478 		if (clp->cl_proto != data->proto)
479 			continue;
480 		/* Match nfsv4 minorversion */
481 		if (clp->cl_minorversion != data->minorversion)
482 			continue;
483 		/* Match the full socket address */
484 		if (!nfs_sockaddr_cmp(sap, clap))
485 			continue;
486 		/* Match network namespace */
487 		if (clp->net != data->net)
488 			continue;
489 
490 		atomic_inc(&clp->cl_count);
491 		return clp;
492 	}
493 	return NULL;
494 }
495 
496 /*
497  * Look up a client by IP address and protocol version
498  * - creates a new record if one doesn't yet exist
499  */
500 static struct nfs_client *
501 nfs_get_client(const struct nfs_client_initdata *cl_init,
502 	       const struct rpc_timeout *timeparms,
503 	       const char *ip_addr,
504 	       rpc_authflavor_t authflavour,
505 	       int noresvport)
506 {
507 	struct nfs_client *clp, *new = NULL;
508 	int error;
509 
510 	dprintk("--> nfs_get_client(%s,v%u)\n",
511 		cl_init->hostname ?: "", cl_init->rpc_ops->version);
512 
513 	/* see if the client already exists */
514 	do {
515 		spin_lock(&nfs_client_lock);
516 
517 		clp = nfs_match_client(cl_init);
518 		if (clp)
519 			goto found_client;
520 		if (new)
521 			goto install_client;
522 
523 		spin_unlock(&nfs_client_lock);
524 
525 		new = nfs_alloc_client(cl_init);
526 	} while (!IS_ERR(new));
527 
528 	dprintk("--> nfs_get_client() = %ld [failed]\n", PTR_ERR(new));
529 	return new;
530 
531 	/* install a new client and return with it unready */
532 install_client:
533 	clp = new;
534 	list_add(&clp->cl_share_link, &nfs_client_list);
535 	spin_unlock(&nfs_client_lock);
536 
537 	error = cl_init->rpc_ops->init_client(clp, timeparms, ip_addr,
538 					      authflavour, noresvport);
539 	if (error < 0) {
540 		nfs_put_client(clp);
541 		return ERR_PTR(error);
542 	}
543 	dprintk("--> nfs_get_client() = %p [new]\n", clp);
544 	return clp;
545 
546 	/* found an existing client
547 	 * - make sure it's ready before returning
548 	 */
549 found_client:
550 	spin_unlock(&nfs_client_lock);
551 
552 	if (new)
553 		nfs_free_client(new);
554 
555 	error = wait_event_killable(nfs_client_active_wq,
556 				clp->cl_cons_state < NFS_CS_INITING);
557 	if (error < 0) {
558 		nfs_put_client(clp);
559 		return ERR_PTR(-ERESTARTSYS);
560 	}
561 
562 	if (clp->cl_cons_state < NFS_CS_READY) {
563 		error = clp->cl_cons_state;
564 		nfs_put_client(clp);
565 		return ERR_PTR(error);
566 	}
567 
568 	BUG_ON(clp->cl_cons_state != NFS_CS_READY);
569 
570 	dprintk("--> nfs_get_client() = %p [share]\n", clp);
571 	return clp;
572 }
573 
574 /*
575  * Mark a server as ready or failed
576  */
577 void nfs_mark_client_ready(struct nfs_client *clp, int state)
578 {
579 	clp->cl_cons_state = state;
580 	wake_up_all(&nfs_client_active_wq);
581 }
582 
583 /*
584  * With sessions, the client is not marked ready until after a
585  * successful EXCHANGE_ID and CREATE_SESSION.
586  *
587  * Map errors cl_cons_state errors to EPROTONOSUPPORT to indicate
588  * other versions of NFS can be tried.
589  */
590 int nfs4_check_client_ready(struct nfs_client *clp)
591 {
592 	if (!nfs4_has_session(clp))
593 		return 0;
594 	if (clp->cl_cons_state < NFS_CS_READY)
595 		return -EPROTONOSUPPORT;
596 	return 0;
597 }
598 
599 /*
600  * Initialise the timeout values for a connection
601  */
602 static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
603 				    unsigned int timeo, unsigned int retrans)
604 {
605 	to->to_initval = timeo * HZ / 10;
606 	to->to_retries = retrans;
607 
608 	switch (proto) {
609 	case XPRT_TRANSPORT_TCP:
610 	case XPRT_TRANSPORT_RDMA:
611 		if (to->to_retries == 0)
612 			to->to_retries = NFS_DEF_TCP_RETRANS;
613 		if (to->to_initval == 0)
614 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
615 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
616 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
617 		to->to_increment = to->to_initval;
618 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
619 		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
620 			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
621 		if (to->to_maxval < to->to_initval)
622 			to->to_maxval = to->to_initval;
623 		to->to_exponential = 0;
624 		break;
625 	case XPRT_TRANSPORT_UDP:
626 		if (to->to_retries == 0)
627 			to->to_retries = NFS_DEF_UDP_RETRANS;
628 		if (!to->to_initval)
629 			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
630 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
631 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
632 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
633 		to->to_exponential = 1;
634 		break;
635 	default:
636 		BUG();
637 	}
638 }
639 
640 /*
641  * Create an RPC client handle
642  */
643 static int nfs_create_rpc_client(struct nfs_client *clp,
644 				 const struct rpc_timeout *timeparms,
645 				 rpc_authflavor_t flavor,
646 				 int discrtry, int noresvport)
647 {
648 	struct rpc_clnt		*clnt = NULL;
649 	struct rpc_create_args args = {
650 		.net		= clp->net,
651 		.protocol	= clp->cl_proto,
652 		.address	= (struct sockaddr *)&clp->cl_addr,
653 		.addrsize	= clp->cl_addrlen,
654 		.timeout	= timeparms,
655 		.servername	= clp->cl_hostname,
656 		.program	= &nfs_program,
657 		.version	= clp->rpc_ops->version,
658 		.authflavor	= flavor,
659 	};
660 
661 	if (discrtry)
662 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
663 	if (noresvport)
664 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
665 
666 	if (!IS_ERR(clp->cl_rpcclient))
667 		return 0;
668 
669 	clnt = rpc_create(&args);
670 	if (IS_ERR(clnt)) {
671 		dprintk("%s: cannot create RPC client. Error = %ld\n",
672 				__func__, PTR_ERR(clnt));
673 		return PTR_ERR(clnt);
674 	}
675 
676 	clp->cl_rpcclient = clnt;
677 	return 0;
678 }
679 
680 /*
681  * Version 2 or 3 client destruction
682  */
683 static void nfs_destroy_server(struct nfs_server *server)
684 {
685 	if (!(server->flags & NFS_MOUNT_LOCAL_FLOCK) ||
686 			!(server->flags & NFS_MOUNT_LOCAL_FCNTL))
687 		nlmclnt_done(server->nlm_host);
688 }
689 
690 /*
691  * Version 2 or 3 lockd setup
692  */
693 static int nfs_start_lockd(struct nfs_server *server)
694 {
695 	struct nlm_host *host;
696 	struct nfs_client *clp = server->nfs_client;
697 	struct nlmclnt_initdata nlm_init = {
698 		.hostname	= clp->cl_hostname,
699 		.address	= (struct sockaddr *)&clp->cl_addr,
700 		.addrlen	= clp->cl_addrlen,
701 		.nfs_version	= clp->rpc_ops->version,
702 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
703 					1 : 0,
704 	};
705 
706 	if (nlm_init.nfs_version > 3)
707 		return 0;
708 	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
709 			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
710 		return 0;
711 
712 	switch (clp->cl_proto) {
713 		default:
714 			nlm_init.protocol = IPPROTO_TCP;
715 			break;
716 		case XPRT_TRANSPORT_UDP:
717 			nlm_init.protocol = IPPROTO_UDP;
718 	}
719 
720 	host = nlmclnt_init(&nlm_init);
721 	if (IS_ERR(host))
722 		return PTR_ERR(host);
723 
724 	server->nlm_host = host;
725 	server->destroy = nfs_destroy_server;
726 	return 0;
727 }
728 
729 /*
730  * Initialise an NFSv3 ACL client connection
731  */
732 #ifdef CONFIG_NFS_V3_ACL
733 static void nfs_init_server_aclclient(struct nfs_server *server)
734 {
735 	if (server->nfs_client->rpc_ops->version != 3)
736 		goto out_noacl;
737 	if (server->flags & NFS_MOUNT_NOACL)
738 		goto out_noacl;
739 
740 	server->client_acl = rpc_bind_new_program(server->client, &nfsacl_program, 3);
741 	if (IS_ERR(server->client_acl))
742 		goto out_noacl;
743 
744 	/* No errors! Assume that Sun nfsacls are supported */
745 	server->caps |= NFS_CAP_ACLS;
746 	return;
747 
748 out_noacl:
749 	server->caps &= ~NFS_CAP_ACLS;
750 }
751 #else
752 static inline void nfs_init_server_aclclient(struct nfs_server *server)
753 {
754 	server->flags &= ~NFS_MOUNT_NOACL;
755 	server->caps &= ~NFS_CAP_ACLS;
756 }
757 #endif
758 
759 /*
760  * Create a general RPC client
761  */
762 static int nfs_init_server_rpcclient(struct nfs_server *server,
763 		const struct rpc_timeout *timeo,
764 		rpc_authflavor_t pseudoflavour)
765 {
766 	struct nfs_client *clp = server->nfs_client;
767 
768 	server->client = rpc_clone_client(clp->cl_rpcclient);
769 	if (IS_ERR(server->client)) {
770 		dprintk("%s: couldn't create rpc_client!\n", __func__);
771 		return PTR_ERR(server->client);
772 	}
773 
774 	memcpy(&server->client->cl_timeout_default,
775 			timeo,
776 			sizeof(server->client->cl_timeout_default));
777 	server->client->cl_timeout = &server->client->cl_timeout_default;
778 
779 	if (pseudoflavour != clp->cl_rpcclient->cl_auth->au_flavor) {
780 		struct rpc_auth *auth;
781 
782 		auth = rpcauth_create(pseudoflavour, server->client);
783 		if (IS_ERR(auth)) {
784 			dprintk("%s: couldn't create credcache!\n", __func__);
785 			return PTR_ERR(auth);
786 		}
787 	}
788 	server->client->cl_softrtry = 0;
789 	if (server->flags & NFS_MOUNT_SOFT)
790 		server->client->cl_softrtry = 1;
791 
792 	return 0;
793 }
794 
795 /*
796  * Initialise an NFS2 or NFS3 client
797  */
798 int nfs_init_client(struct nfs_client *clp, const struct rpc_timeout *timeparms,
799 		    const char *ip_addr, rpc_authflavor_t authflavour,
800 		    int noresvport)
801 {
802 	int error;
803 
804 	if (clp->cl_cons_state == NFS_CS_READY) {
805 		/* the client is already initialised */
806 		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
807 		return 0;
808 	}
809 
810 	/*
811 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
812 	 * - RFC 2623, sec 2.3.2
813 	 */
814 	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX,
815 				      0, noresvport);
816 	if (error < 0)
817 		goto error;
818 	nfs_mark_client_ready(clp, NFS_CS_READY);
819 	return 0;
820 
821 error:
822 	nfs_mark_client_ready(clp, error);
823 	dprintk("<-- nfs_init_client() = xerror %d\n", error);
824 	return error;
825 }
826 
827 /*
828  * Create a version 2 or 3 client
829  */
830 static int nfs_init_server(struct nfs_server *server,
831 			   const struct nfs_parsed_mount_data *data)
832 {
833 	struct nfs_client_initdata cl_init = {
834 		.hostname = data->nfs_server.hostname,
835 		.addr = (const struct sockaddr *)&data->nfs_server.address,
836 		.addrlen = data->nfs_server.addrlen,
837 		.rpc_ops = &nfs_v2_clientops,
838 		.proto = data->nfs_server.protocol,
839 		.net = data->net,
840 	};
841 	struct rpc_timeout timeparms;
842 	struct nfs_client *clp;
843 	int error;
844 
845 	dprintk("--> nfs_init_server()\n");
846 
847 #ifdef CONFIG_NFS_V3
848 	if (data->version == 3)
849 		cl_init.rpc_ops = &nfs_v3_clientops;
850 #endif
851 
852 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
853 			data->timeo, data->retrans);
854 
855 	/* Allocate or find a client reference we can use */
856 	clp = nfs_get_client(&cl_init, &timeparms, NULL, RPC_AUTH_UNIX,
857 			     data->flags & NFS_MOUNT_NORESVPORT);
858 	if (IS_ERR(clp)) {
859 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
860 		return PTR_ERR(clp);
861 	}
862 
863 	server->nfs_client = clp;
864 
865 	/* Initialise the client representation from the mount data */
866 	server->flags = data->flags;
867 	server->options = data->options;
868 	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
869 		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
870 		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
871 
872 	if (data->rsize)
873 		server->rsize = nfs_block_size(data->rsize, NULL);
874 	if (data->wsize)
875 		server->wsize = nfs_block_size(data->wsize, NULL);
876 
877 	server->acregmin = data->acregmin * HZ;
878 	server->acregmax = data->acregmax * HZ;
879 	server->acdirmin = data->acdirmin * HZ;
880 	server->acdirmax = data->acdirmax * HZ;
881 
882 	/* Start lockd here, before we might error out */
883 	error = nfs_start_lockd(server);
884 	if (error < 0)
885 		goto error;
886 
887 	server->port = data->nfs_server.port;
888 
889 	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
890 	if (error < 0)
891 		goto error;
892 
893 	/* Preserve the values of mount_server-related mount options */
894 	if (data->mount_server.addrlen) {
895 		memcpy(&server->mountd_address, &data->mount_server.address,
896 			data->mount_server.addrlen);
897 		server->mountd_addrlen = data->mount_server.addrlen;
898 	}
899 	server->mountd_version = data->mount_server.version;
900 	server->mountd_port = data->mount_server.port;
901 	server->mountd_protocol = data->mount_server.protocol;
902 
903 	server->namelen  = data->namlen;
904 	/* Create a client RPC handle for the NFSv3 ACL management interface */
905 	nfs_init_server_aclclient(server);
906 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
907 	return 0;
908 
909 error:
910 	server->nfs_client = NULL;
911 	nfs_put_client(clp);
912 	dprintk("<-- nfs_init_server() = xerror %d\n", error);
913 	return error;
914 }
915 
916 /*
917  * Load up the server record from information gained in an fsinfo record
918  */
919 static void nfs_server_set_fsinfo(struct nfs_server *server,
920 				  struct nfs_fh *mntfh,
921 				  struct nfs_fsinfo *fsinfo)
922 {
923 	unsigned long max_rpc_payload;
924 
925 	/* Work out a lot of parameters */
926 	if (server->rsize == 0)
927 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
928 	if (server->wsize == 0)
929 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
930 
931 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
932 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
933 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
934 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
935 
936 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
937 	if (server->rsize > max_rpc_payload)
938 		server->rsize = max_rpc_payload;
939 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
940 		server->rsize = NFS_MAX_FILE_IO_SIZE;
941 	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
942 
943 	server->backing_dev_info.name = "nfs";
944 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
945 
946 	if (server->wsize > max_rpc_payload)
947 		server->wsize = max_rpc_payload;
948 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
949 		server->wsize = NFS_MAX_FILE_IO_SIZE;
950 	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
951 	server->pnfs_blksize = fsinfo->blksize;
952 	set_pnfs_layoutdriver(server, mntfh, fsinfo->layouttype);
953 
954 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
955 
956 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
957 	if (server->dtsize > PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES)
958 		server->dtsize = PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES;
959 	if (server->dtsize > server->rsize)
960 		server->dtsize = server->rsize;
961 
962 	if (server->flags & NFS_MOUNT_NOAC) {
963 		server->acregmin = server->acregmax = 0;
964 		server->acdirmin = server->acdirmax = 0;
965 	}
966 
967 	server->maxfilesize = fsinfo->maxfilesize;
968 
969 	server->time_delta = fsinfo->time_delta;
970 
971 	/* We're airborne Set socket buffersize */
972 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
973 }
974 
975 /*
976  * Probe filesystem information, including the FSID on v2/v3
977  */
978 static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
979 {
980 	struct nfs_fsinfo fsinfo;
981 	struct nfs_client *clp = server->nfs_client;
982 	int error;
983 
984 	dprintk("--> nfs_probe_fsinfo()\n");
985 
986 	if (clp->rpc_ops->set_capabilities != NULL) {
987 		error = clp->rpc_ops->set_capabilities(server, mntfh);
988 		if (error < 0)
989 			goto out_error;
990 	}
991 
992 	fsinfo.fattr = fattr;
993 	fsinfo.layouttype = 0;
994 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
995 	if (error < 0)
996 		goto out_error;
997 
998 	nfs_server_set_fsinfo(server, mntfh, &fsinfo);
999 
1000 	/* Get some general file system info */
1001 	if (server->namelen == 0) {
1002 		struct nfs_pathconf pathinfo;
1003 
1004 		pathinfo.fattr = fattr;
1005 		nfs_fattr_init(fattr);
1006 
1007 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
1008 			server->namelen = pathinfo.max_namelen;
1009 	}
1010 
1011 	dprintk("<-- nfs_probe_fsinfo() = 0\n");
1012 	return 0;
1013 
1014 out_error:
1015 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
1016 	return error;
1017 }
1018 
1019 /*
1020  * Copy useful information when duplicating a server record
1021  */
1022 static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
1023 {
1024 	target->flags = source->flags;
1025 	target->rsize = source->rsize;
1026 	target->wsize = source->wsize;
1027 	target->acregmin = source->acregmin;
1028 	target->acregmax = source->acregmax;
1029 	target->acdirmin = source->acdirmin;
1030 	target->acdirmax = source->acdirmax;
1031 	target->caps = source->caps;
1032 	target->options = source->options;
1033 }
1034 
1035 static void nfs_server_insert_lists(struct nfs_server *server)
1036 {
1037 	struct nfs_client *clp = server->nfs_client;
1038 
1039 	spin_lock(&nfs_client_lock);
1040 	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
1041 	list_add_tail(&server->master_link, &nfs_volume_list);
1042 	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
1043 	spin_unlock(&nfs_client_lock);
1044 
1045 }
1046 
1047 static void nfs_server_remove_lists(struct nfs_server *server)
1048 {
1049 	struct nfs_client *clp = server->nfs_client;
1050 
1051 	spin_lock(&nfs_client_lock);
1052 	list_del_rcu(&server->client_link);
1053 	if (clp && list_empty(&clp->cl_superblocks))
1054 		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
1055 	list_del(&server->master_link);
1056 	spin_unlock(&nfs_client_lock);
1057 
1058 	synchronize_rcu();
1059 }
1060 
1061 /*
1062  * Allocate and initialise a server record
1063  */
1064 static struct nfs_server *nfs_alloc_server(void)
1065 {
1066 	struct nfs_server *server;
1067 
1068 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
1069 	if (!server)
1070 		return NULL;
1071 
1072 	server->client = server->client_acl = ERR_PTR(-EINVAL);
1073 
1074 	/* Zero out the NFS state stuff */
1075 	INIT_LIST_HEAD(&server->client_link);
1076 	INIT_LIST_HEAD(&server->master_link);
1077 	INIT_LIST_HEAD(&server->delegations);
1078 	INIT_LIST_HEAD(&server->layouts);
1079 	INIT_LIST_HEAD(&server->state_owners_lru);
1080 
1081 	atomic_set(&server->active, 0);
1082 
1083 	server->io_stats = nfs_alloc_iostats();
1084 	if (!server->io_stats) {
1085 		kfree(server);
1086 		return NULL;
1087 	}
1088 
1089 	if (bdi_init(&server->backing_dev_info)) {
1090 		nfs_free_iostats(server->io_stats);
1091 		kfree(server);
1092 		return NULL;
1093 	}
1094 
1095 	ida_init(&server->openowner_id);
1096 	ida_init(&server->lockowner_id);
1097 	pnfs_init_server(server);
1098 
1099 	return server;
1100 }
1101 
1102 /*
1103  * Free up a server record
1104  */
1105 void nfs_free_server(struct nfs_server *server)
1106 {
1107 	dprintk("--> nfs_free_server()\n");
1108 
1109 	nfs_server_remove_lists(server);
1110 	unset_pnfs_layoutdriver(server);
1111 
1112 	if (server->destroy != NULL)
1113 		server->destroy(server);
1114 
1115 	if (!IS_ERR(server->client_acl))
1116 		rpc_shutdown_client(server->client_acl);
1117 	if (!IS_ERR(server->client))
1118 		rpc_shutdown_client(server->client);
1119 
1120 	nfs_put_client(server->nfs_client);
1121 
1122 	ida_destroy(&server->lockowner_id);
1123 	ida_destroy(&server->openowner_id);
1124 	nfs_free_iostats(server->io_stats);
1125 	bdi_destroy(&server->backing_dev_info);
1126 	kfree(server);
1127 	nfs_release_automount_timer();
1128 	dprintk("<-- nfs_free_server()\n");
1129 }
1130 
1131 /*
1132  * Create a version 2 or 3 volume record
1133  * - keyed on server and FSID
1134  */
1135 struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
1136 				     struct nfs_fh *mntfh)
1137 {
1138 	struct nfs_server *server;
1139 	struct nfs_fattr *fattr;
1140 	int error;
1141 
1142 	server = nfs_alloc_server();
1143 	if (!server)
1144 		return ERR_PTR(-ENOMEM);
1145 
1146 	error = -ENOMEM;
1147 	fattr = nfs_alloc_fattr();
1148 	if (fattr == NULL)
1149 		goto error;
1150 
1151 	/* Get a client representation */
1152 	error = nfs_init_server(server, data);
1153 	if (error < 0)
1154 		goto error;
1155 
1156 	BUG_ON(!server->nfs_client);
1157 	BUG_ON(!server->nfs_client->rpc_ops);
1158 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1159 
1160 	/* Probe the root fh to retrieve its FSID */
1161 	error = nfs_probe_fsinfo(server, mntfh, fattr);
1162 	if (error < 0)
1163 		goto error;
1164 	if (server->nfs_client->rpc_ops->version == 3) {
1165 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
1166 			server->namelen = NFS3_MAXNAMLEN;
1167 		if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
1168 			server->caps |= NFS_CAP_READDIRPLUS;
1169 	} else {
1170 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
1171 			server->namelen = NFS2_MAXNAMLEN;
1172 	}
1173 
1174 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
1175 		error = server->nfs_client->rpc_ops->getattr(server, mntfh, fattr);
1176 		if (error < 0) {
1177 			dprintk("nfs_create_server: getattr error = %d\n", -error);
1178 			goto error;
1179 		}
1180 	}
1181 	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1182 
1183 	dprintk("Server FSID: %llx:%llx\n",
1184 		(unsigned long long) server->fsid.major,
1185 		(unsigned long long) server->fsid.minor);
1186 
1187 	nfs_server_insert_lists(server);
1188 	server->mount_time = jiffies;
1189 	nfs_free_fattr(fattr);
1190 	return server;
1191 
1192 error:
1193 	nfs_free_fattr(fattr);
1194 	nfs_free_server(server);
1195 	return ERR_PTR(error);
1196 }
1197 
1198 #ifdef CONFIG_NFS_V4
1199 /*
1200  * NFSv4.0 callback thread helper
1201  *
1202  * Find a client by callback identifier
1203  */
1204 struct nfs_client *
1205 nfs4_find_client_ident(int cb_ident)
1206 {
1207 	struct nfs_client *clp;
1208 
1209 	spin_lock(&nfs_client_lock);
1210 	clp = idr_find(&cb_ident_idr, cb_ident);
1211 	if (clp)
1212 		atomic_inc(&clp->cl_count);
1213 	spin_unlock(&nfs_client_lock);
1214 	return clp;
1215 }
1216 
1217 #if defined(CONFIG_NFS_V4_1)
1218 /*
1219  * NFSv4.1 callback thread helper
1220  * For CB_COMPOUND calls, find a client by IP address, protocol version,
1221  * minorversion, and sessionID
1222  *
1223  * Returns NULL if no such client
1224  */
1225 struct nfs_client *
1226 nfs4_find_client_sessionid(const struct sockaddr *addr,
1227 			   struct nfs4_sessionid *sid)
1228 {
1229 	struct nfs_client *clp;
1230 
1231 	spin_lock(&nfs_client_lock);
1232 	list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
1233 		if (nfs4_cb_match_client(addr, clp, 1) == false)
1234 			continue;
1235 
1236 		if (!nfs4_has_session(clp))
1237 			continue;
1238 
1239 		/* Match sessionid*/
1240 		if (memcmp(clp->cl_session->sess_id.data,
1241 		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
1242 			continue;
1243 
1244 		atomic_inc(&clp->cl_count);
1245 		spin_unlock(&nfs_client_lock);
1246 		return clp;
1247 	}
1248 	spin_unlock(&nfs_client_lock);
1249 	return NULL;
1250 }
1251 
1252 #else /* CONFIG_NFS_V4_1 */
1253 
1254 struct nfs_client *
1255 nfs4_find_client_sessionid(const struct sockaddr *addr,
1256 			   struct nfs4_sessionid *sid)
1257 {
1258 	return NULL;
1259 }
1260 #endif /* CONFIG_NFS_V4_1 */
1261 
1262 /*
1263  * Initialize the NFS4 callback service
1264  */
1265 static int nfs4_init_callback(struct nfs_client *clp)
1266 {
1267 	int error;
1268 
1269 	if (clp->rpc_ops->version == 4) {
1270 		if (nfs4_has_session(clp)) {
1271 			error = xprt_setup_backchannel(
1272 						clp->cl_rpcclient->cl_xprt,
1273 						NFS41_BC_MIN_CALLBACKS);
1274 			if (error < 0)
1275 				return error;
1276 		}
1277 
1278 		error = nfs_callback_up(clp->cl_mvops->minor_version,
1279 					clp->cl_rpcclient->cl_xprt);
1280 		if (error < 0) {
1281 			dprintk("%s: failed to start callback. Error = %d\n",
1282 				__func__, error);
1283 			return error;
1284 		}
1285 		__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
1286 	}
1287 	return 0;
1288 }
1289 
1290 /*
1291  * Initialize the minor version specific parts of an NFS4 client record
1292  */
1293 static int nfs4_init_client_minor_version(struct nfs_client *clp)
1294 {
1295 #if defined(CONFIG_NFS_V4_1)
1296 	if (clp->cl_mvops->minor_version) {
1297 		struct nfs4_session *session = NULL;
1298 		/*
1299 		 * Create the session and mark it expired.
1300 		 * When a SEQUENCE operation encounters the expired session
1301 		 * it will do session recovery to initialize it.
1302 		 */
1303 		session = nfs4_alloc_session(clp);
1304 		if (!session)
1305 			return -ENOMEM;
1306 
1307 		clp->cl_session = session;
1308 		/*
1309 		 * The create session reply races with the server back
1310 		 * channel probe. Mark the client NFS_CS_SESSION_INITING
1311 		 * so that the client back channel can find the
1312 		 * nfs_client struct
1313 		 */
1314 		clp->cl_cons_state = NFS_CS_SESSION_INITING;
1315 	}
1316 #endif /* CONFIG_NFS_V4_1 */
1317 
1318 	return nfs4_init_callback(clp);
1319 }
1320 
1321 /*
1322  * Initialise an NFS4 client record
1323  */
1324 int nfs4_init_client(struct nfs_client *clp,
1325 		     const struct rpc_timeout *timeparms,
1326 		     const char *ip_addr,
1327 		     rpc_authflavor_t authflavour,
1328 		     int noresvport)
1329 {
1330 	int error;
1331 
1332 	if (clp->cl_cons_state == NFS_CS_READY) {
1333 		/* the client is initialised already */
1334 		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
1335 		return 0;
1336 	}
1337 
1338 	/* Check NFS protocol revision and initialize RPC op vector */
1339 	clp->rpc_ops = &nfs_v4_clientops;
1340 
1341 	error = nfs_create_rpc_client(clp, timeparms, authflavour,
1342 				      1, noresvport);
1343 	if (error < 0)
1344 		goto error;
1345 	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
1346 
1347 	error = nfs_idmap_new(clp);
1348 	if (error < 0) {
1349 		dprintk("%s: failed to create idmapper. Error = %d\n",
1350 			__func__, error);
1351 		goto error;
1352 	}
1353 	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
1354 
1355 	error = nfs4_init_client_minor_version(clp);
1356 	if (error < 0)
1357 		goto error;
1358 
1359 	if (!nfs4_has_session(clp))
1360 		nfs_mark_client_ready(clp, NFS_CS_READY);
1361 	return 0;
1362 
1363 error:
1364 	nfs_mark_client_ready(clp, error);
1365 	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
1366 	return error;
1367 }
1368 
1369 /*
1370  * Set up an NFS4 client
1371  */
1372 static int nfs4_set_client(struct nfs_server *server,
1373 		const char *hostname,
1374 		const struct sockaddr *addr,
1375 		const size_t addrlen,
1376 		const char *ip_addr,
1377 		rpc_authflavor_t authflavour,
1378 		int proto, const struct rpc_timeout *timeparms,
1379 		u32 minorversion, struct net *net)
1380 {
1381 	struct nfs_client_initdata cl_init = {
1382 		.hostname = hostname,
1383 		.addr = addr,
1384 		.addrlen = addrlen,
1385 		.rpc_ops = &nfs_v4_clientops,
1386 		.proto = proto,
1387 		.minorversion = minorversion,
1388 		.net = net,
1389 	};
1390 	struct nfs_client *clp;
1391 	int error;
1392 
1393 	dprintk("--> nfs4_set_client()\n");
1394 
1395 	/* Allocate or find a client reference we can use */
1396 	clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour,
1397 			     server->flags & NFS_MOUNT_NORESVPORT);
1398 	if (IS_ERR(clp)) {
1399 		error = PTR_ERR(clp);
1400 		goto error;
1401 	}
1402 
1403 	/*
1404 	 * Query for the lease time on clientid setup or renewal
1405 	 *
1406 	 * Note that this will be set on nfs_clients that were created
1407 	 * only for the DS role and did not set this bit, but now will
1408 	 * serve a dual role.
1409 	 */
1410 	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
1411 
1412 	server->nfs_client = clp;
1413 	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
1414 	return 0;
1415 error:
1416 	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
1417 	return error;
1418 }
1419 
1420 /*
1421  * Set up a pNFS Data Server client.
1422  *
1423  * Return any existing nfs_client that matches server address,port,version
1424  * and minorversion.
1425  *
1426  * For a new nfs_client, use a soft mount (default), a low retrans and a
1427  * low timeout interval so that if a connection is lost, we retry through
1428  * the MDS.
1429  */
1430 struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
1431 		const struct sockaddr *ds_addr,
1432 		int ds_addrlen, int ds_proto)
1433 {
1434 	struct nfs_client_initdata cl_init = {
1435 		.addr = ds_addr,
1436 		.addrlen = ds_addrlen,
1437 		.rpc_ops = &nfs_v4_clientops,
1438 		.proto = ds_proto,
1439 		.minorversion = mds_clp->cl_minorversion,
1440 		.net = mds_clp->net,
1441 	};
1442 	struct rpc_timeout ds_timeout = {
1443 		.to_initval = 15 * HZ,
1444 		.to_maxval = 15 * HZ,
1445 		.to_retries = 1,
1446 		.to_exponential = 1,
1447 	};
1448 	struct nfs_client *clp;
1449 
1450 	/*
1451 	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
1452 	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
1453 	 * (section 13.1 RFC 5661).
1454 	 */
1455 	clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
1456 			     mds_clp->cl_rpcclient->cl_auth->au_flavor, 0);
1457 
1458 	dprintk("<-- %s %p\n", __func__, clp);
1459 	return clp;
1460 }
1461 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
1462 
1463 /*
1464  * Session has been established, and the client marked ready.
1465  * Set the mount rsize and wsize with negotiated fore channel
1466  * attributes which will be bound checked in nfs_server_set_fsinfo.
1467  */
1468 static void nfs4_session_set_rwsize(struct nfs_server *server)
1469 {
1470 #ifdef CONFIG_NFS_V4_1
1471 	struct nfs4_session *sess;
1472 	u32 server_resp_sz;
1473 	u32 server_rqst_sz;
1474 
1475 	if (!nfs4_has_session(server->nfs_client))
1476 		return;
1477 	sess = server->nfs_client->cl_session;
1478 	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
1479 	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
1480 
1481 	if (server->rsize > server_resp_sz)
1482 		server->rsize = server_resp_sz;
1483 	if (server->wsize > server_rqst_sz)
1484 		server->wsize = server_rqst_sz;
1485 #endif /* CONFIG_NFS_V4_1 */
1486 }
1487 
1488 static int nfs4_server_common_setup(struct nfs_server *server,
1489 		struct nfs_fh *mntfh)
1490 {
1491 	struct nfs_fattr *fattr;
1492 	int error;
1493 
1494 	BUG_ON(!server->nfs_client);
1495 	BUG_ON(!server->nfs_client->rpc_ops);
1496 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1497 
1498 	/* data servers support only a subset of NFSv4.1 */
1499 	if (is_ds_only_client(server->nfs_client))
1500 		return -EPROTONOSUPPORT;
1501 
1502 	fattr = nfs_alloc_fattr();
1503 	if (fattr == NULL)
1504 		return -ENOMEM;
1505 
1506 	/* We must ensure the session is initialised first */
1507 	error = nfs4_init_session(server);
1508 	if (error < 0)
1509 		goto out;
1510 
1511 	/* Probe the root fh to retrieve its FSID and filehandle */
1512 	error = nfs4_get_rootfh(server, mntfh);
1513 	if (error < 0)
1514 		goto out;
1515 
1516 	dprintk("Server FSID: %llx:%llx\n",
1517 			(unsigned long long) server->fsid.major,
1518 			(unsigned long long) server->fsid.minor);
1519 	dprintk("Mount FH: %d\n", mntfh->size);
1520 
1521 	nfs4_session_set_rwsize(server);
1522 
1523 	error = nfs_probe_fsinfo(server, mntfh, fattr);
1524 	if (error < 0)
1525 		goto out;
1526 
1527 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1528 		server->namelen = NFS4_MAXNAMLEN;
1529 
1530 	nfs_server_insert_lists(server);
1531 	server->mount_time = jiffies;
1532 	server->destroy = nfs4_destroy_server;
1533 out:
1534 	nfs_free_fattr(fattr);
1535 	return error;
1536 }
1537 
1538 /*
1539  * Create a version 4 volume record
1540  */
1541 static int nfs4_init_server(struct nfs_server *server,
1542 		const struct nfs_parsed_mount_data *data)
1543 {
1544 	struct rpc_timeout timeparms;
1545 	int error;
1546 
1547 	dprintk("--> nfs4_init_server()\n");
1548 
1549 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1550 			data->timeo, data->retrans);
1551 
1552 	/* Initialise the client representation from the mount data */
1553 	server->flags = data->flags;
1554 	server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|NFS_CAP_POSIX_LOCK;
1555 	if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
1556 			server->caps |= NFS_CAP_READDIRPLUS;
1557 	server->options = data->options;
1558 
1559 	/* Get a client record */
1560 	error = nfs4_set_client(server,
1561 			data->nfs_server.hostname,
1562 			(const struct sockaddr *)&data->nfs_server.address,
1563 			data->nfs_server.addrlen,
1564 			data->client_address,
1565 			data->auth_flavors[0],
1566 			data->nfs_server.protocol,
1567 			&timeparms,
1568 			data->minorversion,
1569 			data->net);
1570 	if (error < 0)
1571 		goto error;
1572 
1573 	/*
1574 	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
1575 	 * authentication.
1576 	 */
1577 	if (nfs4_disable_idmapping && data->auth_flavors[0] == RPC_AUTH_UNIX)
1578 		server->caps |= NFS_CAP_UIDGID_NOMAP;
1579 
1580 	if (data->rsize)
1581 		server->rsize = nfs_block_size(data->rsize, NULL);
1582 	if (data->wsize)
1583 		server->wsize = nfs_block_size(data->wsize, NULL);
1584 
1585 	server->acregmin = data->acregmin * HZ;
1586 	server->acregmax = data->acregmax * HZ;
1587 	server->acdirmin = data->acdirmin * HZ;
1588 	server->acdirmax = data->acdirmax * HZ;
1589 
1590 	server->port = data->nfs_server.port;
1591 
1592 	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
1593 
1594 error:
1595 	/* Done */
1596 	dprintk("<-- nfs4_init_server() = %d\n", error);
1597 	return error;
1598 }
1599 
1600 /*
1601  * Create a version 4 volume record
1602  * - keyed on server and FSID
1603  */
1604 struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1605 				      struct nfs_fh *mntfh)
1606 {
1607 	struct nfs_server *server;
1608 	int error;
1609 
1610 	dprintk("--> nfs4_create_server()\n");
1611 
1612 	server = nfs_alloc_server();
1613 	if (!server)
1614 		return ERR_PTR(-ENOMEM);
1615 
1616 	/* set up the general RPC client */
1617 	error = nfs4_init_server(server, data);
1618 	if (error < 0)
1619 		goto error;
1620 
1621 	error = nfs4_server_common_setup(server, mntfh);
1622 	if (error < 0)
1623 		goto error;
1624 
1625 	dprintk("<-- nfs4_create_server() = %p\n", server);
1626 	return server;
1627 
1628 error:
1629 	nfs_free_server(server);
1630 	dprintk("<-- nfs4_create_server() = error %d\n", error);
1631 	return ERR_PTR(error);
1632 }
1633 
1634 /*
1635  * Create an NFS4 referral server record
1636  */
1637 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1638 					       struct nfs_fh *mntfh)
1639 {
1640 	struct nfs_client *parent_client;
1641 	struct nfs_server *server, *parent_server;
1642 	int error;
1643 
1644 	dprintk("--> nfs4_create_referral_server()\n");
1645 
1646 	server = nfs_alloc_server();
1647 	if (!server)
1648 		return ERR_PTR(-ENOMEM);
1649 
1650 	parent_server = NFS_SB(data->sb);
1651 	parent_client = parent_server->nfs_client;
1652 
1653 	/* Initialise the client representation from the parent server */
1654 	nfs_server_copy_userdata(server, parent_server);
1655 	server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR;
1656 
1657 	/* Get a client representation.
1658 	 * Note: NFSv4 always uses TCP, */
1659 	error = nfs4_set_client(server, data->hostname,
1660 				data->addr,
1661 				data->addrlen,
1662 				parent_client->cl_ipaddr,
1663 				data->authflavor,
1664 				parent_server->client->cl_xprt->prot,
1665 				parent_server->client->cl_timeout,
1666 				parent_client->cl_mvops->minor_version,
1667 				parent_client->net);
1668 	if (error < 0)
1669 		goto error;
1670 
1671 	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1672 	if (error < 0)
1673 		goto error;
1674 
1675 	error = nfs4_server_common_setup(server, mntfh);
1676 	if (error < 0)
1677 		goto error;
1678 
1679 	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1680 	return server;
1681 
1682 error:
1683 	nfs_free_server(server);
1684 	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1685 	return ERR_PTR(error);
1686 }
1687 
1688 #endif /* CONFIG_NFS_V4 */
1689 
1690 /*
1691  * Clone an NFS2, NFS3 or NFS4 server record
1692  */
1693 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1694 				    struct nfs_fh *fh,
1695 				    struct nfs_fattr *fattr)
1696 {
1697 	struct nfs_server *server;
1698 	struct nfs_fattr *fattr_fsinfo;
1699 	int error;
1700 
1701 	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1702 		(unsigned long long) fattr->fsid.major,
1703 		(unsigned long long) fattr->fsid.minor);
1704 
1705 	server = nfs_alloc_server();
1706 	if (!server)
1707 		return ERR_PTR(-ENOMEM);
1708 
1709 	error = -ENOMEM;
1710 	fattr_fsinfo = nfs_alloc_fattr();
1711 	if (fattr_fsinfo == NULL)
1712 		goto out_free_server;
1713 
1714 	/* Copy data from the source */
1715 	server->nfs_client = source->nfs_client;
1716 	server->destroy = source->destroy;
1717 	atomic_inc(&server->nfs_client->cl_count);
1718 	nfs_server_copy_userdata(server, source);
1719 
1720 	server->fsid = fattr->fsid;
1721 
1722 	error = nfs_init_server_rpcclient(server,
1723 			source->client->cl_timeout,
1724 			source->client->cl_auth->au_flavor);
1725 	if (error < 0)
1726 		goto out_free_server;
1727 	if (!IS_ERR(source->client_acl))
1728 		nfs_init_server_aclclient(server);
1729 
1730 	/* probe the filesystem info for this server filesystem */
1731 	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1732 	if (error < 0)
1733 		goto out_free_server;
1734 
1735 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1736 		server->namelen = NFS4_MAXNAMLEN;
1737 
1738 	dprintk("Cloned FSID: %llx:%llx\n",
1739 		(unsigned long long) server->fsid.major,
1740 		(unsigned long long) server->fsid.minor);
1741 
1742 	error = nfs_start_lockd(server);
1743 	if (error < 0)
1744 		goto out_free_server;
1745 
1746 	nfs_server_insert_lists(server);
1747 	server->mount_time = jiffies;
1748 
1749 	nfs_free_fattr(fattr_fsinfo);
1750 	dprintk("<-- nfs_clone_server() = %p\n", server);
1751 	return server;
1752 
1753 out_free_server:
1754 	nfs_free_fattr(fattr_fsinfo);
1755 	nfs_free_server(server);
1756 	dprintk("<-- nfs_clone_server() = error %d\n", error);
1757 	return ERR_PTR(error);
1758 }
1759 
1760 #ifdef CONFIG_PROC_FS
1761 static struct proc_dir_entry *proc_fs_nfs;
1762 
1763 static int nfs_server_list_open(struct inode *inode, struct file *file);
1764 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1765 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1766 static void nfs_server_list_stop(struct seq_file *p, void *v);
1767 static int nfs_server_list_show(struct seq_file *m, void *v);
1768 
1769 static const struct seq_operations nfs_server_list_ops = {
1770 	.start	= nfs_server_list_start,
1771 	.next	= nfs_server_list_next,
1772 	.stop	= nfs_server_list_stop,
1773 	.show	= nfs_server_list_show,
1774 };
1775 
1776 static const struct file_operations nfs_server_list_fops = {
1777 	.open		= nfs_server_list_open,
1778 	.read		= seq_read,
1779 	.llseek		= seq_lseek,
1780 	.release	= seq_release,
1781 	.owner		= THIS_MODULE,
1782 };
1783 
1784 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1785 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1786 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1787 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1788 static int nfs_volume_list_show(struct seq_file *m, void *v);
1789 
1790 static const struct seq_operations nfs_volume_list_ops = {
1791 	.start	= nfs_volume_list_start,
1792 	.next	= nfs_volume_list_next,
1793 	.stop	= nfs_volume_list_stop,
1794 	.show	= nfs_volume_list_show,
1795 };
1796 
1797 static const struct file_operations nfs_volume_list_fops = {
1798 	.open		= nfs_volume_list_open,
1799 	.read		= seq_read,
1800 	.llseek		= seq_lseek,
1801 	.release	= seq_release,
1802 	.owner		= THIS_MODULE,
1803 };
1804 
1805 /*
1806  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1807  * we're dealing
1808  */
1809 static int nfs_server_list_open(struct inode *inode, struct file *file)
1810 {
1811 	struct seq_file *m;
1812 	int ret;
1813 
1814 	ret = seq_open(file, &nfs_server_list_ops);
1815 	if (ret < 0)
1816 		return ret;
1817 
1818 	m = file->private_data;
1819 	m->private = PDE(inode)->data;
1820 
1821 	return 0;
1822 }
1823 
1824 /*
1825  * set up the iterator to start reading from the server list and return the first item
1826  */
1827 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1828 {
1829 	/* lock the list against modification */
1830 	spin_lock(&nfs_client_lock);
1831 	return seq_list_start_head(&nfs_client_list, *_pos);
1832 }
1833 
1834 /*
1835  * move to next server
1836  */
1837 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1838 {
1839 	return seq_list_next(v, &nfs_client_list, pos);
1840 }
1841 
1842 /*
1843  * clean up after reading from the transports list
1844  */
1845 static void nfs_server_list_stop(struct seq_file *p, void *v)
1846 {
1847 	spin_unlock(&nfs_client_lock);
1848 }
1849 
1850 /*
1851  * display a header line followed by a load of call lines
1852  */
1853 static int nfs_server_list_show(struct seq_file *m, void *v)
1854 {
1855 	struct nfs_client *clp;
1856 
1857 	/* display header on line 1 */
1858 	if (v == &nfs_client_list) {
1859 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1860 		return 0;
1861 	}
1862 
1863 	/* display one transport per line on subsequent lines */
1864 	clp = list_entry(v, struct nfs_client, cl_share_link);
1865 
1866 	/* Check if the client is initialized */
1867 	if (clp->cl_cons_state != NFS_CS_READY)
1868 		return 0;
1869 
1870 	seq_printf(m, "v%u %s %s %3d %s\n",
1871 		   clp->rpc_ops->version,
1872 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1873 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1874 		   atomic_read(&clp->cl_count),
1875 		   clp->cl_hostname);
1876 
1877 	return 0;
1878 }
1879 
1880 /*
1881  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1882  */
1883 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1884 {
1885 	struct seq_file *m;
1886 	int ret;
1887 
1888 	ret = seq_open(file, &nfs_volume_list_ops);
1889 	if (ret < 0)
1890 		return ret;
1891 
1892 	m = file->private_data;
1893 	m->private = PDE(inode)->data;
1894 
1895 	return 0;
1896 }
1897 
1898 /*
1899  * set up the iterator to start reading from the volume list and return the first item
1900  */
1901 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1902 {
1903 	/* lock the list against modification */
1904 	spin_lock(&nfs_client_lock);
1905 	return seq_list_start_head(&nfs_volume_list, *_pos);
1906 }
1907 
1908 /*
1909  * move to next volume
1910  */
1911 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1912 {
1913 	return seq_list_next(v, &nfs_volume_list, pos);
1914 }
1915 
1916 /*
1917  * clean up after reading from the transports list
1918  */
1919 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1920 {
1921 	spin_unlock(&nfs_client_lock);
1922 }
1923 
1924 /*
1925  * display a header line followed by a load of call lines
1926  */
1927 static int nfs_volume_list_show(struct seq_file *m, void *v)
1928 {
1929 	struct nfs_server *server;
1930 	struct nfs_client *clp;
1931 	char dev[8], fsid[17];
1932 
1933 	/* display header on line 1 */
1934 	if (v == &nfs_volume_list) {
1935 		seq_puts(m, "NV SERVER   PORT DEV     FSID              FSC\n");
1936 		return 0;
1937 	}
1938 	/* display one transport per line on subsequent lines */
1939 	server = list_entry(v, struct nfs_server, master_link);
1940 	clp = server->nfs_client;
1941 
1942 	snprintf(dev, 8, "%u:%u",
1943 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1944 
1945 	snprintf(fsid, 17, "%llx:%llx",
1946 		 (unsigned long long) server->fsid.major,
1947 		 (unsigned long long) server->fsid.minor);
1948 
1949 	seq_printf(m, "v%u %s %s %-7s %-17s %s\n",
1950 		   clp->rpc_ops->version,
1951 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1952 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1953 		   dev,
1954 		   fsid,
1955 		   nfs_server_fscache_state(server));
1956 
1957 	return 0;
1958 }
1959 
1960 /*
1961  * initialise the /proc/fs/nfsfs/ directory
1962  */
1963 int __init nfs_fs_proc_init(void)
1964 {
1965 	struct proc_dir_entry *p;
1966 
1967 	proc_fs_nfs = proc_mkdir("fs/nfsfs", NULL);
1968 	if (!proc_fs_nfs)
1969 		goto error_0;
1970 
1971 	/* a file of servers with which we're dealing */
1972 	p = proc_create("servers", S_IFREG|S_IRUGO,
1973 			proc_fs_nfs, &nfs_server_list_fops);
1974 	if (!p)
1975 		goto error_1;
1976 
1977 	/* a file of volumes that we have mounted */
1978 	p = proc_create("volumes", S_IFREG|S_IRUGO,
1979 			proc_fs_nfs, &nfs_volume_list_fops);
1980 	if (!p)
1981 		goto error_2;
1982 	return 0;
1983 
1984 error_2:
1985 	remove_proc_entry("servers", proc_fs_nfs);
1986 error_1:
1987 	remove_proc_entry("fs/nfsfs", NULL);
1988 error_0:
1989 	return -ENOMEM;
1990 }
1991 
1992 /*
1993  * clean up the /proc/fs/nfsfs/ directory
1994  */
1995 void nfs_fs_proc_exit(void)
1996 {
1997 	remove_proc_entry("volumes", proc_fs_nfs);
1998 	remove_proc_entry("servers", proc_fs_nfs);
1999 	remove_proc_entry("fs/nfsfs", NULL);
2000 }
2001 
2002 #endif /* CONFIG_PROC_FS */
2003 
2004 module_param(nfs4_disable_idmapping, bool, 0644);
2005 MODULE_PARM_DESC(nfs4_disable_idmapping,
2006 		"Turn off NFSv4 idmapping when using 'sec=sys'");
2007