xref: /openbmc/linux/fs/nfs/client.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
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 <net/ipv6.h>
39 #include <linux/nfs_xdr.h>
40 
41 #include <asm/system.h>
42 
43 #include "nfs4_fs.h"
44 #include "callback.h"
45 #include "delegation.h"
46 #include "iostat.h"
47 #include "internal.h"
48 
49 #define NFSDBG_FACILITY		NFSDBG_CLIENT
50 
51 static DEFINE_SPINLOCK(nfs_client_lock);
52 static LIST_HEAD(nfs_client_list);
53 static LIST_HEAD(nfs_volume_list);
54 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
55 
56 /*
57  * RPC cruft for NFS
58  */
59 static struct rpc_version *nfs_version[5] = {
60 	[2]			= &nfs_version2,
61 #ifdef CONFIG_NFS_V3
62 	[3]			= &nfs_version3,
63 #endif
64 #ifdef CONFIG_NFS_V4
65 	[4]			= &nfs_version4,
66 #endif
67 };
68 
69 struct rpc_program nfs_program = {
70 	.name			= "nfs",
71 	.number			= NFS_PROGRAM,
72 	.nrvers			= ARRAY_SIZE(nfs_version),
73 	.version		= nfs_version,
74 	.stats			= &nfs_rpcstat,
75 	.pipe_dir_name		= "/nfs",
76 };
77 
78 struct rpc_stat nfs_rpcstat = {
79 	.program		= &nfs_program
80 };
81 
82 
83 #ifdef CONFIG_NFS_V3_ACL
84 static struct rpc_stat		nfsacl_rpcstat = { &nfsacl_program };
85 static struct rpc_version *	nfsacl_version[] = {
86 	[3]			= &nfsacl_version3,
87 };
88 
89 struct rpc_program		nfsacl_program = {
90 	.name			= "nfsacl",
91 	.number			= NFS_ACL_PROGRAM,
92 	.nrvers			= ARRAY_SIZE(nfsacl_version),
93 	.version		= nfsacl_version,
94 	.stats			= &nfsacl_rpcstat,
95 };
96 #endif  /* CONFIG_NFS_V3_ACL */
97 
98 struct nfs_client_initdata {
99 	const char *hostname;
100 	const struct sockaddr *addr;
101 	size_t addrlen;
102 	const struct nfs_rpc_ops *rpc_ops;
103 	int proto;
104 };
105 
106 /*
107  * Allocate a shared client record
108  *
109  * Since these are allocated/deallocated very rarely, we don't
110  * bother putting them in a slab cache...
111  */
112 static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
113 {
114 	struct nfs_client *clp;
115 	struct rpc_cred *cred;
116 
117 	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
118 		goto error_0;
119 
120 	clp->rpc_ops = cl_init->rpc_ops;
121 
122 	if (cl_init->rpc_ops->version == 4) {
123 		if (nfs_callback_up() < 0)
124 			goto error_2;
125 		__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
126 	}
127 
128 	atomic_set(&clp->cl_count, 1);
129 	clp->cl_cons_state = NFS_CS_INITING;
130 
131 	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
132 	clp->cl_addrlen = cl_init->addrlen;
133 
134 	if (cl_init->hostname) {
135 		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
136 		if (!clp->cl_hostname)
137 			goto error_3;
138 	}
139 
140 	INIT_LIST_HEAD(&clp->cl_superblocks);
141 	clp->cl_rpcclient = ERR_PTR(-EINVAL);
142 
143 	clp->cl_proto = cl_init->proto;
144 
145 #ifdef CONFIG_NFS_V4
146 	INIT_LIST_HEAD(&clp->cl_delegations);
147 	spin_lock_init(&clp->cl_lock);
148 	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
149 	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
150 	clp->cl_boot_time = CURRENT_TIME;
151 	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
152 #endif
153 	cred = rpc_lookup_machine_cred();
154 	if (!IS_ERR(cred))
155 		clp->cl_machine_cred = cred;
156 
157 	return clp;
158 
159 error_3:
160 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
161 		nfs_callback_down();
162 error_2:
163 	kfree(clp);
164 error_0:
165 	return NULL;
166 }
167 
168 static void nfs4_shutdown_client(struct nfs_client *clp)
169 {
170 #ifdef CONFIG_NFS_V4
171 	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
172 		nfs4_kill_renewd(clp);
173 	BUG_ON(!RB_EMPTY_ROOT(&clp->cl_state_owners));
174 	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
175 		nfs_idmap_delete(clp);
176 
177 	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
178 #endif
179 }
180 
181 /*
182  * Destroy a shared client record
183  */
184 static void nfs_free_client(struct nfs_client *clp)
185 {
186 	dprintk("--> nfs_free_client(%u)\n", clp->rpc_ops->version);
187 
188 	nfs4_shutdown_client(clp);
189 
190 	/* -EIO all pending I/O */
191 	if (!IS_ERR(clp->cl_rpcclient))
192 		rpc_shutdown_client(clp->cl_rpcclient);
193 
194 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
195 		nfs_callback_down();
196 
197 	if (clp->cl_machine_cred != NULL)
198 		put_rpccred(clp->cl_machine_cred);
199 
200 	kfree(clp->cl_hostname);
201 	kfree(clp);
202 
203 	dprintk("<-- nfs_free_client()\n");
204 }
205 
206 /*
207  * Release a reference to a shared client record
208  */
209 void nfs_put_client(struct nfs_client *clp)
210 {
211 	if (!clp)
212 		return;
213 
214 	dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
215 
216 	if (atomic_dec_and_lock(&clp->cl_count, &nfs_client_lock)) {
217 		list_del(&clp->cl_share_link);
218 		spin_unlock(&nfs_client_lock);
219 
220 		BUG_ON(!list_empty(&clp->cl_superblocks));
221 
222 		nfs_free_client(clp);
223 	}
224 }
225 
226 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
227 /*
228  * Test if two ip6 socket addresses refer to the same socket by
229  * comparing relevant fields. The padding bytes specifically, are not
230  * compared. sin6_flowinfo is not compared because it only affects QoS
231  * and sin6_scope_id is only compared if the address is "link local"
232  * because "link local" addresses need only be unique to a specific
233  * link. Conversely, ordinary unicast addresses might have different
234  * sin6_scope_id.
235  *
236  * The caller should ensure both socket addresses are AF_INET6.
237  */
238 static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
239 				      const struct sockaddr *sa2)
240 {
241 	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
242 	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
243 
244 	if (ipv6_addr_scope(&sin1->sin6_addr) == IPV6_ADDR_SCOPE_LINKLOCAL &&
245 	    sin1->sin6_scope_id != sin2->sin6_scope_id)
246 		return 0;
247 
248 	return ipv6_addr_equal(&sin1->sin6_addr, &sin1->sin6_addr);
249 }
250 #else	/* !defined(CONFIG_IPV6) && !defined(CONFIG_IPV6_MODULE) */
251 static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
252 				      const struct sockaddr *sa2)
253 {
254 	return 0;
255 }
256 #endif
257 
258 /*
259  * Test if two ip4 socket addresses refer to the same socket, by
260  * comparing relevant fields. The padding bytes specifically, are
261  * not compared.
262  *
263  * The caller should ensure both socket addresses are AF_INET.
264  */
265 static int nfs_sockaddr_match_ipaddr4(const struct sockaddr *sa1,
266 				      const struct sockaddr *sa2)
267 {
268 	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
269 	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
270 
271 	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
272 }
273 
274 static int nfs_sockaddr_cmp_ip6(const struct sockaddr *sa1,
275 				const struct sockaddr *sa2)
276 {
277 	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
278 	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
279 
280 	return nfs_sockaddr_match_ipaddr6(sa1, sa2) &&
281 		(sin1->sin6_port == sin2->sin6_port);
282 }
283 
284 static int nfs_sockaddr_cmp_ip4(const struct sockaddr *sa1,
285 				const struct sockaddr *sa2)
286 {
287 	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
288 	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
289 
290 	return nfs_sockaddr_match_ipaddr4(sa1, sa2) &&
291 		(sin1->sin_port == sin2->sin_port);
292 }
293 
294 /*
295  * Test if two socket addresses represent the same actual socket,
296  * by comparing (only) relevant fields, excluding the port number.
297  */
298 static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
299 				     const struct sockaddr *sa2)
300 {
301 	if (sa1->sa_family != sa2->sa_family)
302 		return 0;
303 
304 	switch (sa1->sa_family) {
305 	case AF_INET:
306 		return nfs_sockaddr_match_ipaddr4(sa1, sa2);
307 	case AF_INET6:
308 		return nfs_sockaddr_match_ipaddr6(sa1, sa2);
309 	}
310 	return 0;
311 }
312 
313 /*
314  * Test if two socket addresses represent the same actual socket,
315  * by comparing (only) relevant fields, including the port number.
316  */
317 static int nfs_sockaddr_cmp(const struct sockaddr *sa1,
318 			    const struct sockaddr *sa2)
319 {
320 	if (sa1->sa_family != sa2->sa_family)
321 		return 0;
322 
323 	switch (sa1->sa_family) {
324 	case AF_INET:
325 		return nfs_sockaddr_cmp_ip4(sa1, sa2);
326 	case AF_INET6:
327 		return nfs_sockaddr_cmp_ip6(sa1, sa2);
328 	}
329 	return 0;
330 }
331 
332 /*
333  * Find a client by IP address and protocol version
334  * - returns NULL if no such client
335  */
336 struct nfs_client *nfs_find_client(const struct sockaddr *addr, u32 nfsversion)
337 {
338 	struct nfs_client *clp;
339 
340 	spin_lock(&nfs_client_lock);
341 	list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
342 		struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
343 
344 		/* Don't match clients that failed to initialise properly */
345 		if (clp->cl_cons_state != NFS_CS_READY)
346 			continue;
347 
348 		/* Different NFS versions cannot share the same nfs_client */
349 		if (clp->rpc_ops->version != nfsversion)
350 			continue;
351 
352 		/* Match only the IP address, not the port number */
353 		if (!nfs_sockaddr_match_ipaddr(addr, clap))
354 			continue;
355 
356 		atomic_inc(&clp->cl_count);
357 		spin_unlock(&nfs_client_lock);
358 		return clp;
359 	}
360 	spin_unlock(&nfs_client_lock);
361 	return NULL;
362 }
363 
364 /*
365  * Find a client by IP address and protocol version
366  * - returns NULL if no such client
367  */
368 struct nfs_client *nfs_find_client_next(struct nfs_client *clp)
369 {
370 	struct sockaddr *sap = (struct sockaddr *)&clp->cl_addr;
371 	u32 nfsvers = clp->rpc_ops->version;
372 
373 	spin_lock(&nfs_client_lock);
374 	list_for_each_entry_continue(clp, &nfs_client_list, cl_share_link) {
375 		struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
376 
377 		/* Don't match clients that failed to initialise properly */
378 		if (clp->cl_cons_state != NFS_CS_READY)
379 			continue;
380 
381 		/* Different NFS versions cannot share the same nfs_client */
382 		if (clp->rpc_ops->version != nfsvers)
383 			continue;
384 
385 		/* Match only the IP address, not the port number */
386 		if (!nfs_sockaddr_match_ipaddr(sap, clap))
387 			continue;
388 
389 		atomic_inc(&clp->cl_count);
390 		spin_unlock(&nfs_client_lock);
391 		return clp;
392 	}
393 	spin_unlock(&nfs_client_lock);
394 	return NULL;
395 }
396 
397 /*
398  * Find an nfs_client on the list that matches the initialisation data
399  * that is supplied.
400  */
401 static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
402 {
403 	struct nfs_client *clp;
404 	const struct sockaddr *sap = data->addr;
405 
406 	list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
407 	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
408 		/* Don't match clients that failed to initialise properly */
409 		if (clp->cl_cons_state < 0)
410 			continue;
411 
412 		/* Different NFS versions cannot share the same nfs_client */
413 		if (clp->rpc_ops != data->rpc_ops)
414 			continue;
415 
416 		if (clp->cl_proto != data->proto)
417 			continue;
418 
419 		/* Match the full socket address */
420 		if (!nfs_sockaddr_cmp(sap, clap))
421 			continue;
422 
423 		atomic_inc(&clp->cl_count);
424 		return clp;
425 	}
426 	return NULL;
427 }
428 
429 /*
430  * Look up a client by IP address and protocol version
431  * - creates a new record if one doesn't yet exist
432  */
433 static struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
434 {
435 	struct nfs_client *clp, *new = NULL;
436 	int error;
437 
438 	dprintk("--> nfs_get_client(%s,v%u)\n",
439 		cl_init->hostname ?: "", cl_init->rpc_ops->version);
440 
441 	/* see if the client already exists */
442 	do {
443 		spin_lock(&nfs_client_lock);
444 
445 		clp = nfs_match_client(cl_init);
446 		if (clp)
447 			goto found_client;
448 		if (new)
449 			goto install_client;
450 
451 		spin_unlock(&nfs_client_lock);
452 
453 		new = nfs_alloc_client(cl_init);
454 	} while (new);
455 
456 	return ERR_PTR(-ENOMEM);
457 
458 	/* install a new client and return with it unready */
459 install_client:
460 	clp = new;
461 	list_add(&clp->cl_share_link, &nfs_client_list);
462 	spin_unlock(&nfs_client_lock);
463 	dprintk("--> nfs_get_client() = %p [new]\n", clp);
464 	return clp;
465 
466 	/* found an existing client
467 	 * - make sure it's ready before returning
468 	 */
469 found_client:
470 	spin_unlock(&nfs_client_lock);
471 
472 	if (new)
473 		nfs_free_client(new);
474 
475 	error = wait_event_killable(nfs_client_active_wq,
476 				clp->cl_cons_state != NFS_CS_INITING);
477 	if (error < 0) {
478 		nfs_put_client(clp);
479 		return ERR_PTR(-ERESTARTSYS);
480 	}
481 
482 	if (clp->cl_cons_state < NFS_CS_READY) {
483 		error = clp->cl_cons_state;
484 		nfs_put_client(clp);
485 		return ERR_PTR(error);
486 	}
487 
488 	BUG_ON(clp->cl_cons_state != NFS_CS_READY);
489 
490 	dprintk("--> nfs_get_client() = %p [share]\n", clp);
491 	return clp;
492 }
493 
494 /*
495  * Mark a server as ready or failed
496  */
497 static void nfs_mark_client_ready(struct nfs_client *clp, int state)
498 {
499 	clp->cl_cons_state = state;
500 	wake_up_all(&nfs_client_active_wq);
501 }
502 
503 /*
504  * Initialise the timeout values for a connection
505  */
506 static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
507 				    unsigned int timeo, unsigned int retrans)
508 {
509 	to->to_initval = timeo * HZ / 10;
510 	to->to_retries = retrans;
511 
512 	switch (proto) {
513 	case XPRT_TRANSPORT_TCP:
514 	case XPRT_TRANSPORT_RDMA:
515 		if (to->to_retries == 0)
516 			to->to_retries = NFS_DEF_TCP_RETRANS;
517 		if (to->to_initval == 0)
518 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
519 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
520 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
521 		to->to_increment = to->to_initval;
522 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
523 		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
524 			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
525 		if (to->to_maxval < to->to_initval)
526 			to->to_maxval = to->to_initval;
527 		to->to_exponential = 0;
528 		break;
529 	case XPRT_TRANSPORT_UDP:
530 		if (to->to_retries == 0)
531 			to->to_retries = NFS_DEF_UDP_RETRANS;
532 		if (!to->to_initval)
533 			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
534 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
535 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
536 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
537 		to->to_exponential = 1;
538 		break;
539 	default:
540 		BUG();
541 	}
542 }
543 
544 /*
545  * Create an RPC client handle
546  */
547 static int nfs_create_rpc_client(struct nfs_client *clp,
548 				 const struct rpc_timeout *timeparms,
549 				 rpc_authflavor_t flavor,
550 				 int discrtry, int noresvport)
551 {
552 	struct rpc_clnt		*clnt = NULL;
553 	struct rpc_create_args args = {
554 		.protocol	= clp->cl_proto,
555 		.address	= (struct sockaddr *)&clp->cl_addr,
556 		.addrsize	= clp->cl_addrlen,
557 		.timeout	= timeparms,
558 		.servername	= clp->cl_hostname,
559 		.program	= &nfs_program,
560 		.version	= clp->rpc_ops->version,
561 		.authflavor	= flavor,
562 	};
563 
564 	if (discrtry)
565 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
566 	if (noresvport)
567 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
568 
569 	if (!IS_ERR(clp->cl_rpcclient))
570 		return 0;
571 
572 	clnt = rpc_create(&args);
573 	if (IS_ERR(clnt)) {
574 		dprintk("%s: cannot create RPC client. Error = %ld\n",
575 				__func__, PTR_ERR(clnt));
576 		return PTR_ERR(clnt);
577 	}
578 
579 	clp->cl_rpcclient = clnt;
580 	return 0;
581 }
582 
583 /*
584  * Version 2 or 3 client destruction
585  */
586 static void nfs_destroy_server(struct nfs_server *server)
587 {
588 	if (!(server->flags & NFS_MOUNT_NONLM))
589 		nlmclnt_done(server->nlm_host);
590 }
591 
592 /*
593  * Version 2 or 3 lockd setup
594  */
595 static int nfs_start_lockd(struct nfs_server *server)
596 {
597 	struct nlm_host *host;
598 	struct nfs_client *clp = server->nfs_client;
599 	struct nlmclnt_initdata nlm_init = {
600 		.hostname	= clp->cl_hostname,
601 		.address	= (struct sockaddr *)&clp->cl_addr,
602 		.addrlen	= clp->cl_addrlen,
603 		.protocol	= server->flags & NFS_MOUNT_TCP ?
604 						IPPROTO_TCP : IPPROTO_UDP,
605 		.nfs_version	= clp->rpc_ops->version,
606 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
607 					1 : 0,
608 	};
609 
610 	if (nlm_init.nfs_version > 3)
611 		return 0;
612 	if (server->flags & NFS_MOUNT_NONLM)
613 		return 0;
614 
615 	host = nlmclnt_init(&nlm_init);
616 	if (IS_ERR(host))
617 		return PTR_ERR(host);
618 
619 	server->nlm_host = host;
620 	server->destroy = nfs_destroy_server;
621 	return 0;
622 }
623 
624 /*
625  * Initialise an NFSv3 ACL client connection
626  */
627 #ifdef CONFIG_NFS_V3_ACL
628 static void nfs_init_server_aclclient(struct nfs_server *server)
629 {
630 	if (server->nfs_client->rpc_ops->version != 3)
631 		goto out_noacl;
632 	if (server->flags & NFS_MOUNT_NOACL)
633 		goto out_noacl;
634 
635 	server->client_acl = rpc_bind_new_program(server->client, &nfsacl_program, 3);
636 	if (IS_ERR(server->client_acl))
637 		goto out_noacl;
638 
639 	/* No errors! Assume that Sun nfsacls are supported */
640 	server->caps |= NFS_CAP_ACLS;
641 	return;
642 
643 out_noacl:
644 	server->caps &= ~NFS_CAP_ACLS;
645 }
646 #else
647 static inline void nfs_init_server_aclclient(struct nfs_server *server)
648 {
649 	server->flags &= ~NFS_MOUNT_NOACL;
650 	server->caps &= ~NFS_CAP_ACLS;
651 }
652 #endif
653 
654 /*
655  * Create a general RPC client
656  */
657 static int nfs_init_server_rpcclient(struct nfs_server *server,
658 		const struct rpc_timeout *timeo,
659 		rpc_authflavor_t pseudoflavour)
660 {
661 	struct nfs_client *clp = server->nfs_client;
662 
663 	server->client = rpc_clone_client(clp->cl_rpcclient);
664 	if (IS_ERR(server->client)) {
665 		dprintk("%s: couldn't create rpc_client!\n", __func__);
666 		return PTR_ERR(server->client);
667 	}
668 
669 	memcpy(&server->client->cl_timeout_default,
670 			timeo,
671 			sizeof(server->client->cl_timeout_default));
672 	server->client->cl_timeout = &server->client->cl_timeout_default;
673 
674 	if (pseudoflavour != clp->cl_rpcclient->cl_auth->au_flavor) {
675 		struct rpc_auth *auth;
676 
677 		auth = rpcauth_create(pseudoflavour, server->client);
678 		if (IS_ERR(auth)) {
679 			dprintk("%s: couldn't create credcache!\n", __func__);
680 			return PTR_ERR(auth);
681 		}
682 	}
683 	server->client->cl_softrtry = 0;
684 	if (server->flags & NFS_MOUNT_SOFT)
685 		server->client->cl_softrtry = 1;
686 
687 	return 0;
688 }
689 
690 /*
691  * Initialise an NFS2 or NFS3 client
692  */
693 static int nfs_init_client(struct nfs_client *clp,
694 			   const struct rpc_timeout *timeparms,
695 			   const struct nfs_parsed_mount_data *data)
696 {
697 	int error;
698 
699 	if (clp->cl_cons_state == NFS_CS_READY) {
700 		/* the client is already initialised */
701 		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
702 		return 0;
703 	}
704 
705 	/*
706 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
707 	 * - RFC 2623, sec 2.3.2
708 	 */
709 	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX,
710 				      0, data->flags & NFS_MOUNT_NORESVPORT);
711 	if (error < 0)
712 		goto error;
713 	nfs_mark_client_ready(clp, NFS_CS_READY);
714 	return 0;
715 
716 error:
717 	nfs_mark_client_ready(clp, error);
718 	dprintk("<-- nfs_init_client() = xerror %d\n", error);
719 	return error;
720 }
721 
722 /*
723  * Create a version 2 or 3 client
724  */
725 static int nfs_init_server(struct nfs_server *server,
726 			   const struct nfs_parsed_mount_data *data)
727 {
728 	struct nfs_client_initdata cl_init = {
729 		.hostname = data->nfs_server.hostname,
730 		.addr = (const struct sockaddr *)&data->nfs_server.address,
731 		.addrlen = data->nfs_server.addrlen,
732 		.rpc_ops = &nfs_v2_clientops,
733 		.proto = data->nfs_server.protocol,
734 	};
735 	struct rpc_timeout timeparms;
736 	struct nfs_client *clp;
737 	int error;
738 
739 	dprintk("--> nfs_init_server()\n");
740 
741 #ifdef CONFIG_NFS_V3
742 	if (data->flags & NFS_MOUNT_VER3)
743 		cl_init.rpc_ops = &nfs_v3_clientops;
744 #endif
745 
746 	/* Allocate or find a client reference we can use */
747 	clp = nfs_get_client(&cl_init);
748 	if (IS_ERR(clp)) {
749 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
750 		return PTR_ERR(clp);
751 	}
752 
753 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
754 			data->timeo, data->retrans);
755 	error = nfs_init_client(clp, &timeparms, data);
756 	if (error < 0)
757 		goto error;
758 
759 	server->nfs_client = clp;
760 
761 	/* Initialise the client representation from the mount data */
762 	server->flags = data->flags;
763 
764 	if (data->rsize)
765 		server->rsize = nfs_block_size(data->rsize, NULL);
766 	if (data->wsize)
767 		server->wsize = nfs_block_size(data->wsize, NULL);
768 
769 	server->acregmin = data->acregmin * HZ;
770 	server->acregmax = data->acregmax * HZ;
771 	server->acdirmin = data->acdirmin * HZ;
772 	server->acdirmax = data->acdirmax * HZ;
773 
774 	/* Start lockd here, before we might error out */
775 	error = nfs_start_lockd(server);
776 	if (error < 0)
777 		goto error;
778 
779 	server->port = data->nfs_server.port;
780 
781 	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
782 	if (error < 0)
783 		goto error;
784 
785 	/* Preserve the values of mount_server-related mount options */
786 	if (data->mount_server.addrlen) {
787 		memcpy(&server->mountd_address, &data->mount_server.address,
788 			data->mount_server.addrlen);
789 		server->mountd_addrlen = data->mount_server.addrlen;
790 	}
791 	server->mountd_version = data->mount_server.version;
792 	server->mountd_port = data->mount_server.port;
793 	server->mountd_protocol = data->mount_server.protocol;
794 
795 	server->namelen  = data->namlen;
796 	/* Create a client RPC handle for the NFSv3 ACL management interface */
797 	nfs_init_server_aclclient(server);
798 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
799 	return 0;
800 
801 error:
802 	server->nfs_client = NULL;
803 	nfs_put_client(clp);
804 	dprintk("<-- nfs_init_server() = xerror %d\n", error);
805 	return error;
806 }
807 
808 /*
809  * Load up the server record from information gained in an fsinfo record
810  */
811 static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo *fsinfo)
812 {
813 	unsigned long max_rpc_payload;
814 
815 	/* Work out a lot of parameters */
816 	if (server->rsize == 0)
817 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
818 	if (server->wsize == 0)
819 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
820 
821 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
822 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
823 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
824 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
825 
826 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
827 	if (server->rsize > max_rpc_payload)
828 		server->rsize = max_rpc_payload;
829 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
830 		server->rsize = NFS_MAX_FILE_IO_SIZE;
831 	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
832 
833 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
834 
835 	if (server->wsize > max_rpc_payload)
836 		server->wsize = max_rpc_payload;
837 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
838 		server->wsize = NFS_MAX_FILE_IO_SIZE;
839 	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
840 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
841 
842 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
843 	if (server->dtsize > PAGE_CACHE_SIZE)
844 		server->dtsize = PAGE_CACHE_SIZE;
845 	if (server->dtsize > server->rsize)
846 		server->dtsize = server->rsize;
847 
848 	if (server->flags & NFS_MOUNT_NOAC) {
849 		server->acregmin = server->acregmax = 0;
850 		server->acdirmin = server->acdirmax = 0;
851 	}
852 
853 	server->maxfilesize = fsinfo->maxfilesize;
854 
855 	/* We're airborne Set socket buffersize */
856 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
857 }
858 
859 /*
860  * Probe filesystem information, including the FSID on v2/v3
861  */
862 static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
863 {
864 	struct nfs_fsinfo fsinfo;
865 	struct nfs_client *clp = server->nfs_client;
866 	int error;
867 
868 	dprintk("--> nfs_probe_fsinfo()\n");
869 
870 	if (clp->rpc_ops->set_capabilities != NULL) {
871 		error = clp->rpc_ops->set_capabilities(server, mntfh);
872 		if (error < 0)
873 			goto out_error;
874 	}
875 
876 	fsinfo.fattr = fattr;
877 	nfs_fattr_init(fattr);
878 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
879 	if (error < 0)
880 		goto out_error;
881 
882 	nfs_server_set_fsinfo(server, &fsinfo);
883 	error = bdi_init(&server->backing_dev_info);
884 	if (error)
885 		goto out_error;
886 
887 
888 	/* Get some general file system info */
889 	if (server->namelen == 0) {
890 		struct nfs_pathconf pathinfo;
891 
892 		pathinfo.fattr = fattr;
893 		nfs_fattr_init(fattr);
894 
895 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
896 			server->namelen = pathinfo.max_namelen;
897 	}
898 
899 	dprintk("<-- nfs_probe_fsinfo() = 0\n");
900 	return 0;
901 
902 out_error:
903 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
904 	return error;
905 }
906 
907 /*
908  * Copy useful information when duplicating a server record
909  */
910 static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
911 {
912 	target->flags = source->flags;
913 	target->acregmin = source->acregmin;
914 	target->acregmax = source->acregmax;
915 	target->acdirmin = source->acdirmin;
916 	target->acdirmax = source->acdirmax;
917 	target->caps = source->caps;
918 }
919 
920 /*
921  * Allocate and initialise a server record
922  */
923 static struct nfs_server *nfs_alloc_server(void)
924 {
925 	struct nfs_server *server;
926 
927 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
928 	if (!server)
929 		return NULL;
930 
931 	server->client = server->client_acl = ERR_PTR(-EINVAL);
932 
933 	/* Zero out the NFS state stuff */
934 	INIT_LIST_HEAD(&server->client_link);
935 	INIT_LIST_HEAD(&server->master_link);
936 
937 	atomic_set(&server->active, 0);
938 
939 	server->io_stats = nfs_alloc_iostats();
940 	if (!server->io_stats) {
941 		kfree(server);
942 		return NULL;
943 	}
944 
945 	return server;
946 }
947 
948 /*
949  * Free up a server record
950  */
951 void nfs_free_server(struct nfs_server *server)
952 {
953 	dprintk("--> nfs_free_server()\n");
954 
955 	spin_lock(&nfs_client_lock);
956 	list_del(&server->client_link);
957 	list_del(&server->master_link);
958 	spin_unlock(&nfs_client_lock);
959 
960 	if (server->destroy != NULL)
961 		server->destroy(server);
962 
963 	if (!IS_ERR(server->client_acl))
964 		rpc_shutdown_client(server->client_acl);
965 	if (!IS_ERR(server->client))
966 		rpc_shutdown_client(server->client);
967 
968 	nfs_put_client(server->nfs_client);
969 
970 	nfs_free_iostats(server->io_stats);
971 	bdi_destroy(&server->backing_dev_info);
972 	kfree(server);
973 	nfs_release_automount_timer();
974 	dprintk("<-- nfs_free_server()\n");
975 }
976 
977 /*
978  * Create a version 2 or 3 volume record
979  * - keyed on server and FSID
980  */
981 struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
982 				     struct nfs_fh *mntfh)
983 {
984 	struct nfs_server *server;
985 	struct nfs_fattr fattr;
986 	int error;
987 
988 	server = nfs_alloc_server();
989 	if (!server)
990 		return ERR_PTR(-ENOMEM);
991 
992 	/* Get a client representation */
993 	error = nfs_init_server(server, data);
994 	if (error < 0)
995 		goto error;
996 
997 	BUG_ON(!server->nfs_client);
998 	BUG_ON(!server->nfs_client->rpc_ops);
999 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1000 
1001 	/* Probe the root fh to retrieve its FSID */
1002 	error = nfs_probe_fsinfo(server, mntfh, &fattr);
1003 	if (error < 0)
1004 		goto error;
1005 	if (server->nfs_client->rpc_ops->version == 3) {
1006 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
1007 			server->namelen = NFS3_MAXNAMLEN;
1008 		if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
1009 			server->caps |= NFS_CAP_READDIRPLUS;
1010 	} else {
1011 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
1012 			server->namelen = NFS2_MAXNAMLEN;
1013 	}
1014 
1015 	if (!(fattr.valid & NFS_ATTR_FATTR)) {
1016 		error = server->nfs_client->rpc_ops->getattr(server, mntfh, &fattr);
1017 		if (error < 0) {
1018 			dprintk("nfs_create_server: getattr error = %d\n", -error);
1019 			goto error;
1020 		}
1021 	}
1022 	memcpy(&server->fsid, &fattr.fsid, sizeof(server->fsid));
1023 
1024 	dprintk("Server FSID: %llx:%llx\n",
1025 		(unsigned long long) server->fsid.major,
1026 		(unsigned long long) server->fsid.minor);
1027 
1028 	BUG_ON(!server->nfs_client);
1029 	BUG_ON(!server->nfs_client->rpc_ops);
1030 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1031 
1032 	spin_lock(&nfs_client_lock);
1033 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1034 	list_add_tail(&server->master_link, &nfs_volume_list);
1035 	spin_unlock(&nfs_client_lock);
1036 
1037 	server->mount_time = jiffies;
1038 	return server;
1039 
1040 error:
1041 	nfs_free_server(server);
1042 	return ERR_PTR(error);
1043 }
1044 
1045 #ifdef CONFIG_NFS_V4
1046 /*
1047  * Initialise an NFS4 client record
1048  */
1049 static int nfs4_init_client(struct nfs_client *clp,
1050 		const struct rpc_timeout *timeparms,
1051 		const char *ip_addr,
1052 		rpc_authflavor_t authflavour,
1053 		int flags)
1054 {
1055 	int error;
1056 
1057 	if (clp->cl_cons_state == NFS_CS_READY) {
1058 		/* the client is initialised already */
1059 		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
1060 		return 0;
1061 	}
1062 
1063 	/* Check NFS protocol revision and initialize RPC op vector */
1064 	clp->rpc_ops = &nfs_v4_clientops;
1065 
1066 	error = nfs_create_rpc_client(clp, timeparms, authflavour,
1067 				      1, flags & NFS_MOUNT_NORESVPORT);
1068 	if (error < 0)
1069 		goto error;
1070 	memcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
1071 
1072 	error = nfs_idmap_new(clp);
1073 	if (error < 0) {
1074 		dprintk("%s: failed to create idmapper. Error = %d\n",
1075 			__func__, error);
1076 		goto error;
1077 	}
1078 	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
1079 
1080 	nfs_mark_client_ready(clp, NFS_CS_READY);
1081 	return 0;
1082 
1083 error:
1084 	nfs_mark_client_ready(clp, error);
1085 	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
1086 	return error;
1087 }
1088 
1089 /*
1090  * Set up an NFS4 client
1091  */
1092 static int nfs4_set_client(struct nfs_server *server,
1093 		const char *hostname,
1094 		const struct sockaddr *addr,
1095 		const size_t addrlen,
1096 		const char *ip_addr,
1097 		rpc_authflavor_t authflavour,
1098 		int proto, const struct rpc_timeout *timeparms)
1099 {
1100 	struct nfs_client_initdata cl_init = {
1101 		.hostname = hostname,
1102 		.addr = addr,
1103 		.addrlen = addrlen,
1104 		.rpc_ops = &nfs_v4_clientops,
1105 		.proto = proto,
1106 	};
1107 	struct nfs_client *clp;
1108 	int error;
1109 
1110 	dprintk("--> nfs4_set_client()\n");
1111 
1112 	/* Allocate or find a client reference we can use */
1113 	clp = nfs_get_client(&cl_init);
1114 	if (IS_ERR(clp)) {
1115 		error = PTR_ERR(clp);
1116 		goto error;
1117 	}
1118 	error = nfs4_init_client(clp, timeparms, ip_addr, authflavour,
1119 					server->flags);
1120 	if (error < 0)
1121 		goto error_put;
1122 
1123 	server->nfs_client = clp;
1124 	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
1125 	return 0;
1126 
1127 error_put:
1128 	nfs_put_client(clp);
1129 error:
1130 	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
1131 	return error;
1132 }
1133 
1134 /*
1135  * Create a version 4 volume record
1136  */
1137 static int nfs4_init_server(struct nfs_server *server,
1138 		const struct nfs_parsed_mount_data *data)
1139 {
1140 	struct rpc_timeout timeparms;
1141 	int error;
1142 
1143 	dprintk("--> nfs4_init_server()\n");
1144 
1145 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1146 			data->timeo, data->retrans);
1147 
1148 	/* Initialise the client representation from the mount data */
1149 	server->flags = data->flags;
1150 	server->caps |= NFS_CAP_ATOMIC_OPEN;
1151 
1152 	/* Get a client record */
1153 	error = nfs4_set_client(server,
1154 			data->nfs_server.hostname,
1155 			(const struct sockaddr *)&data->nfs_server.address,
1156 			data->nfs_server.addrlen,
1157 			data->client_address,
1158 			data->auth_flavors[0],
1159 			data->nfs_server.protocol,
1160 			&timeparms);
1161 	if (error < 0)
1162 		goto error;
1163 
1164 	if (data->rsize)
1165 		server->rsize = nfs_block_size(data->rsize, NULL);
1166 	if (data->wsize)
1167 		server->wsize = nfs_block_size(data->wsize, NULL);
1168 
1169 	server->acregmin = data->acregmin * HZ;
1170 	server->acregmax = data->acregmax * HZ;
1171 	server->acdirmin = data->acdirmin * HZ;
1172 	server->acdirmax = data->acdirmax * HZ;
1173 
1174 	server->port = data->nfs_server.port;
1175 
1176 	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
1177 
1178 error:
1179 	/* Done */
1180 	dprintk("<-- nfs4_init_server() = %d\n", error);
1181 	return error;
1182 }
1183 
1184 /*
1185  * Create a version 4 volume record
1186  * - keyed on server and FSID
1187  */
1188 struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1189 				      struct nfs_fh *mntfh)
1190 {
1191 	struct nfs_fattr fattr;
1192 	struct nfs_server *server;
1193 	int error;
1194 
1195 	dprintk("--> nfs4_create_server()\n");
1196 
1197 	server = nfs_alloc_server();
1198 	if (!server)
1199 		return ERR_PTR(-ENOMEM);
1200 
1201 	/* set up the general RPC client */
1202 	error = nfs4_init_server(server, data);
1203 	if (error < 0)
1204 		goto error;
1205 
1206 	BUG_ON(!server->nfs_client);
1207 	BUG_ON(!server->nfs_client->rpc_ops);
1208 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1209 
1210 	/* Probe the root fh to retrieve its FSID */
1211 	error = nfs4_path_walk(server, mntfh, data->nfs_server.export_path);
1212 	if (error < 0)
1213 		goto error;
1214 
1215 	dprintk("Server FSID: %llx:%llx\n",
1216 		(unsigned long long) server->fsid.major,
1217 		(unsigned long long) server->fsid.minor);
1218 	dprintk("Mount FH: %d\n", mntfh->size);
1219 
1220 	error = nfs_probe_fsinfo(server, mntfh, &fattr);
1221 	if (error < 0)
1222 		goto error;
1223 
1224 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1225 		server->namelen = NFS4_MAXNAMLEN;
1226 
1227 	BUG_ON(!server->nfs_client);
1228 	BUG_ON(!server->nfs_client->rpc_ops);
1229 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1230 
1231 	spin_lock(&nfs_client_lock);
1232 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1233 	list_add_tail(&server->master_link, &nfs_volume_list);
1234 	spin_unlock(&nfs_client_lock);
1235 
1236 	server->mount_time = jiffies;
1237 	dprintk("<-- nfs4_create_server() = %p\n", server);
1238 	return server;
1239 
1240 error:
1241 	nfs_free_server(server);
1242 	dprintk("<-- nfs4_create_server() = error %d\n", error);
1243 	return ERR_PTR(error);
1244 }
1245 
1246 /*
1247  * Create an NFS4 referral server record
1248  */
1249 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1250 					       struct nfs_fh *mntfh)
1251 {
1252 	struct nfs_client *parent_client;
1253 	struct nfs_server *server, *parent_server;
1254 	struct nfs_fattr fattr;
1255 	int error;
1256 
1257 	dprintk("--> nfs4_create_referral_server()\n");
1258 
1259 	server = nfs_alloc_server();
1260 	if (!server)
1261 		return ERR_PTR(-ENOMEM);
1262 
1263 	parent_server = NFS_SB(data->sb);
1264 	parent_client = parent_server->nfs_client;
1265 
1266 	/* Initialise the client representation from the parent server */
1267 	nfs_server_copy_userdata(server, parent_server);
1268 	server->caps |= NFS_CAP_ATOMIC_OPEN;
1269 
1270 	/* Get a client representation.
1271 	 * Note: NFSv4 always uses TCP, */
1272 	error = nfs4_set_client(server, data->hostname,
1273 				data->addr,
1274 				data->addrlen,
1275 				parent_client->cl_ipaddr,
1276 				data->authflavor,
1277 				parent_server->client->cl_xprt->prot,
1278 				parent_server->client->cl_timeout);
1279 	if (error < 0)
1280 		goto error;
1281 
1282 	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1283 	if (error < 0)
1284 		goto error;
1285 
1286 	BUG_ON(!server->nfs_client);
1287 	BUG_ON(!server->nfs_client->rpc_ops);
1288 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1289 
1290 	/* Probe the root fh to retrieve its FSID and filehandle */
1291 	error = nfs4_path_walk(server, mntfh, data->mnt_path);
1292 	if (error < 0)
1293 		goto error;
1294 
1295 	/* probe the filesystem info for this server filesystem */
1296 	error = nfs_probe_fsinfo(server, mntfh, &fattr);
1297 	if (error < 0)
1298 		goto error;
1299 
1300 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1301 		server->namelen = NFS4_MAXNAMLEN;
1302 
1303 	dprintk("Referral FSID: %llx:%llx\n",
1304 		(unsigned long long) server->fsid.major,
1305 		(unsigned long long) server->fsid.minor);
1306 
1307 	spin_lock(&nfs_client_lock);
1308 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1309 	list_add_tail(&server->master_link, &nfs_volume_list);
1310 	spin_unlock(&nfs_client_lock);
1311 
1312 	server->mount_time = jiffies;
1313 
1314 	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1315 	return server;
1316 
1317 error:
1318 	nfs_free_server(server);
1319 	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1320 	return ERR_PTR(error);
1321 }
1322 
1323 #endif /* CONFIG_NFS_V4 */
1324 
1325 /*
1326  * Clone an NFS2, NFS3 or NFS4 server record
1327  */
1328 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1329 				    struct nfs_fh *fh,
1330 				    struct nfs_fattr *fattr)
1331 {
1332 	struct nfs_server *server;
1333 	struct nfs_fattr fattr_fsinfo;
1334 	int error;
1335 
1336 	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1337 		(unsigned long long) fattr->fsid.major,
1338 		(unsigned long long) fattr->fsid.minor);
1339 
1340 	server = nfs_alloc_server();
1341 	if (!server)
1342 		return ERR_PTR(-ENOMEM);
1343 
1344 	/* Copy data from the source */
1345 	server->nfs_client = source->nfs_client;
1346 	atomic_inc(&server->nfs_client->cl_count);
1347 	nfs_server_copy_userdata(server, source);
1348 
1349 	server->fsid = fattr->fsid;
1350 
1351 	error = nfs_init_server_rpcclient(server,
1352 			source->client->cl_timeout,
1353 			source->client->cl_auth->au_flavor);
1354 	if (error < 0)
1355 		goto out_free_server;
1356 	if (!IS_ERR(source->client_acl))
1357 		nfs_init_server_aclclient(server);
1358 
1359 	/* probe the filesystem info for this server filesystem */
1360 	error = nfs_probe_fsinfo(server, fh, &fattr_fsinfo);
1361 	if (error < 0)
1362 		goto out_free_server;
1363 
1364 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1365 		server->namelen = NFS4_MAXNAMLEN;
1366 
1367 	dprintk("Cloned FSID: %llx:%llx\n",
1368 		(unsigned long long) server->fsid.major,
1369 		(unsigned long long) server->fsid.minor);
1370 
1371 	error = nfs_start_lockd(server);
1372 	if (error < 0)
1373 		goto out_free_server;
1374 
1375 	spin_lock(&nfs_client_lock);
1376 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1377 	list_add_tail(&server->master_link, &nfs_volume_list);
1378 	spin_unlock(&nfs_client_lock);
1379 
1380 	server->mount_time = jiffies;
1381 
1382 	dprintk("<-- nfs_clone_server() = %p\n", server);
1383 	return server;
1384 
1385 out_free_server:
1386 	nfs_free_server(server);
1387 	dprintk("<-- nfs_clone_server() = error %d\n", error);
1388 	return ERR_PTR(error);
1389 }
1390 
1391 #ifdef CONFIG_PROC_FS
1392 static struct proc_dir_entry *proc_fs_nfs;
1393 
1394 static int nfs_server_list_open(struct inode *inode, struct file *file);
1395 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1396 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1397 static void nfs_server_list_stop(struct seq_file *p, void *v);
1398 static int nfs_server_list_show(struct seq_file *m, void *v);
1399 
1400 static struct seq_operations nfs_server_list_ops = {
1401 	.start	= nfs_server_list_start,
1402 	.next	= nfs_server_list_next,
1403 	.stop	= nfs_server_list_stop,
1404 	.show	= nfs_server_list_show,
1405 };
1406 
1407 static const struct file_operations nfs_server_list_fops = {
1408 	.open		= nfs_server_list_open,
1409 	.read		= seq_read,
1410 	.llseek		= seq_lseek,
1411 	.release	= seq_release,
1412 	.owner		= THIS_MODULE,
1413 };
1414 
1415 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1416 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1417 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1418 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1419 static int nfs_volume_list_show(struct seq_file *m, void *v);
1420 
1421 static struct seq_operations nfs_volume_list_ops = {
1422 	.start	= nfs_volume_list_start,
1423 	.next	= nfs_volume_list_next,
1424 	.stop	= nfs_volume_list_stop,
1425 	.show	= nfs_volume_list_show,
1426 };
1427 
1428 static const struct file_operations nfs_volume_list_fops = {
1429 	.open		= nfs_volume_list_open,
1430 	.read		= seq_read,
1431 	.llseek		= seq_lseek,
1432 	.release	= seq_release,
1433 	.owner		= THIS_MODULE,
1434 };
1435 
1436 /*
1437  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1438  * we're dealing
1439  */
1440 static int nfs_server_list_open(struct inode *inode, struct file *file)
1441 {
1442 	struct seq_file *m;
1443 	int ret;
1444 
1445 	ret = seq_open(file, &nfs_server_list_ops);
1446 	if (ret < 0)
1447 		return ret;
1448 
1449 	m = file->private_data;
1450 	m->private = PDE(inode)->data;
1451 
1452 	return 0;
1453 }
1454 
1455 /*
1456  * set up the iterator to start reading from the server list and return the first item
1457  */
1458 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1459 {
1460 	/* lock the list against modification */
1461 	spin_lock(&nfs_client_lock);
1462 	return seq_list_start_head(&nfs_client_list, *_pos);
1463 }
1464 
1465 /*
1466  * move to next server
1467  */
1468 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1469 {
1470 	return seq_list_next(v, &nfs_client_list, pos);
1471 }
1472 
1473 /*
1474  * clean up after reading from the transports list
1475  */
1476 static void nfs_server_list_stop(struct seq_file *p, void *v)
1477 {
1478 	spin_unlock(&nfs_client_lock);
1479 }
1480 
1481 /*
1482  * display a header line followed by a load of call lines
1483  */
1484 static int nfs_server_list_show(struct seq_file *m, void *v)
1485 {
1486 	struct nfs_client *clp;
1487 
1488 	/* display header on line 1 */
1489 	if (v == &nfs_client_list) {
1490 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1491 		return 0;
1492 	}
1493 
1494 	/* display one transport per line on subsequent lines */
1495 	clp = list_entry(v, struct nfs_client, cl_share_link);
1496 
1497 	seq_printf(m, "v%u %s %s %3d %s\n",
1498 		   clp->rpc_ops->version,
1499 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1500 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1501 		   atomic_read(&clp->cl_count),
1502 		   clp->cl_hostname);
1503 
1504 	return 0;
1505 }
1506 
1507 /*
1508  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1509  */
1510 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1511 {
1512 	struct seq_file *m;
1513 	int ret;
1514 
1515 	ret = seq_open(file, &nfs_volume_list_ops);
1516 	if (ret < 0)
1517 		return ret;
1518 
1519 	m = file->private_data;
1520 	m->private = PDE(inode)->data;
1521 
1522 	return 0;
1523 }
1524 
1525 /*
1526  * set up the iterator to start reading from the volume list and return the first item
1527  */
1528 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1529 {
1530 	/* lock the list against modification */
1531 	spin_lock(&nfs_client_lock);
1532 	return seq_list_start_head(&nfs_volume_list, *_pos);
1533 }
1534 
1535 /*
1536  * move to next volume
1537  */
1538 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1539 {
1540 	return seq_list_next(v, &nfs_volume_list, pos);
1541 }
1542 
1543 /*
1544  * clean up after reading from the transports list
1545  */
1546 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1547 {
1548 	spin_unlock(&nfs_client_lock);
1549 }
1550 
1551 /*
1552  * display a header line followed by a load of call lines
1553  */
1554 static int nfs_volume_list_show(struct seq_file *m, void *v)
1555 {
1556 	struct nfs_server *server;
1557 	struct nfs_client *clp;
1558 	char dev[8], fsid[17];
1559 
1560 	/* display header on line 1 */
1561 	if (v == &nfs_volume_list) {
1562 		seq_puts(m, "NV SERVER   PORT DEV     FSID\n");
1563 		return 0;
1564 	}
1565 	/* display one transport per line on subsequent lines */
1566 	server = list_entry(v, struct nfs_server, master_link);
1567 	clp = server->nfs_client;
1568 
1569 	snprintf(dev, 8, "%u:%u",
1570 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1571 
1572 	snprintf(fsid, 17, "%llx:%llx",
1573 		 (unsigned long long) server->fsid.major,
1574 		 (unsigned long long) server->fsid.minor);
1575 
1576 	seq_printf(m, "v%u %s %s %-7s %-17s\n",
1577 		   clp->rpc_ops->version,
1578 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1579 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1580 		   dev,
1581 		   fsid);
1582 
1583 	return 0;
1584 }
1585 
1586 /*
1587  * initialise the /proc/fs/nfsfs/ directory
1588  */
1589 int __init nfs_fs_proc_init(void)
1590 {
1591 	struct proc_dir_entry *p;
1592 
1593 	proc_fs_nfs = proc_mkdir("fs/nfsfs", NULL);
1594 	if (!proc_fs_nfs)
1595 		goto error_0;
1596 
1597 	/* a file of servers with which we're dealing */
1598 	p = proc_create("servers", S_IFREG|S_IRUGO,
1599 			proc_fs_nfs, &nfs_server_list_fops);
1600 	if (!p)
1601 		goto error_1;
1602 
1603 	/* a file of volumes that we have mounted */
1604 	p = proc_create("volumes", S_IFREG|S_IRUGO,
1605 			proc_fs_nfs, &nfs_volume_list_fops);
1606 	if (!p)
1607 		goto error_2;
1608 	return 0;
1609 
1610 error_2:
1611 	remove_proc_entry("servers", proc_fs_nfs);
1612 error_1:
1613 	remove_proc_entry("fs/nfsfs", NULL);
1614 error_0:
1615 	return -ENOMEM;
1616 }
1617 
1618 /*
1619  * clean up the /proc/fs/nfsfs/ directory
1620  */
1621 void nfs_fs_proc_exit(void)
1622 {
1623 	remove_proc_entry("volumes", proc_fs_nfs);
1624 	remove_proc_entry("servers", proc_fs_nfs);
1625 	remove_proc_entry("fs/nfsfs", NULL);
1626 }
1627 
1628 #endif /* CONFIG_PROC_FS */
1629