xref: /linux/fs/nfs/client.c (revision f8324e20f8289dffc646d64366332e05eaacab25)
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 
52 #define NFSDBG_FACILITY		NFSDBG_CLIENT
53 
54 static DEFINE_SPINLOCK(nfs_client_lock);
55 static LIST_HEAD(nfs_client_list);
56 static LIST_HEAD(nfs_volume_list);
57 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
58 
59 /*
60  * RPC cruft for NFS
61  */
62 static struct rpc_version *nfs_version[5] = {
63 	[2]			= &nfs_version2,
64 #ifdef CONFIG_NFS_V3
65 	[3]			= &nfs_version3,
66 #endif
67 #ifdef CONFIG_NFS_V4
68 	[4]			= &nfs_version4,
69 #endif
70 };
71 
72 struct rpc_program nfs_program = {
73 	.name			= "nfs",
74 	.number			= NFS_PROGRAM,
75 	.nrvers			= ARRAY_SIZE(nfs_version),
76 	.version		= nfs_version,
77 	.stats			= &nfs_rpcstat,
78 	.pipe_dir_name		= "/nfs",
79 };
80 
81 struct rpc_stat nfs_rpcstat = {
82 	.program		= &nfs_program
83 };
84 
85 
86 #ifdef CONFIG_NFS_V3_ACL
87 static struct rpc_stat		nfsacl_rpcstat = { &nfsacl_program };
88 static struct rpc_version *	nfsacl_version[] = {
89 	[3]			= &nfsacl_version3,
90 };
91 
92 struct rpc_program		nfsacl_program = {
93 	.name			= "nfsacl",
94 	.number			= NFS_ACL_PROGRAM,
95 	.nrvers			= ARRAY_SIZE(nfsacl_version),
96 	.version		= nfsacl_version,
97 	.stats			= &nfsacl_rpcstat,
98 };
99 #endif  /* CONFIG_NFS_V3_ACL */
100 
101 struct nfs_client_initdata {
102 	const char *hostname;
103 	const struct sockaddr *addr;
104 	size_t addrlen;
105 	const struct nfs_rpc_ops *rpc_ops;
106 	int proto;
107 	u32 minorversion;
108 };
109 
110 /*
111  * Allocate a shared client record
112  *
113  * Since these are allocated/deallocated very rarely, we don't
114  * bother putting them in a slab cache...
115  */
116 static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
117 {
118 	struct nfs_client *clp;
119 	struct rpc_cred *cred;
120 	int err = -ENOMEM;
121 
122 	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
123 		goto error_0;
124 
125 	clp->rpc_ops = cl_init->rpc_ops;
126 
127 	atomic_set(&clp->cl_count, 1);
128 	clp->cl_cons_state = NFS_CS_INITING;
129 
130 	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
131 	clp->cl_addrlen = cl_init->addrlen;
132 
133 	if (cl_init->hostname) {
134 		err = -ENOMEM;
135 		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
136 		if (!clp->cl_hostname)
137 			goto error_cleanup;
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 	clp->cl_minorversion = cl_init->minorversion;
153 #endif
154 	cred = rpc_lookup_machine_cred();
155 	if (!IS_ERR(cred))
156 		clp->cl_machine_cred = cred;
157 
158 	nfs_fscache_get_client_cookie(clp);
159 
160 	return clp;
161 
162 error_cleanup:
163 	kfree(clp);
164 error_0:
165 	return ERR_PTR(err);
166 }
167 
168 #ifdef CONFIG_NFS_V4
169 /*
170  * Clears/puts all minor version specific parts from an nfs_client struct
171  * reverting it to minorversion 0.
172  */
173 static void nfs4_clear_client_minor_version(struct nfs_client *clp)
174 {
175 #ifdef CONFIG_NFS_V4_1
176 	if (nfs4_has_session(clp)) {
177 		nfs4_destroy_session(clp->cl_session);
178 		clp->cl_session = NULL;
179 	}
180 
181 	clp->cl_call_sync = _nfs4_call_sync;
182 #endif /* CONFIG_NFS_V4_1 */
183 }
184 
185 /*
186  * Destroy the NFS4 callback service
187  */
188 static void nfs4_destroy_callback(struct nfs_client *clp)
189 {
190 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
191 		nfs_callback_down(clp->cl_minorversion);
192 }
193 
194 static void nfs4_shutdown_client(struct nfs_client *clp)
195 {
196 	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
197 		nfs4_kill_renewd(clp);
198 	nfs4_clear_client_minor_version(clp);
199 	nfs4_destroy_callback(clp);
200 	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
201 		nfs_idmap_delete(clp);
202 
203 	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
204 }
205 #else
206 static void nfs4_shutdown_client(struct nfs_client *clp)
207 {
208 }
209 #endif /* CONFIG_NFS_V4 */
210 
211 /*
212  * Destroy a shared client record
213  */
214 static void nfs_free_client(struct nfs_client *clp)
215 {
216 	dprintk("--> nfs_free_client(%u)\n", clp->rpc_ops->version);
217 
218 	nfs4_shutdown_client(clp);
219 
220 	nfs_fscache_release_client_cookie(clp);
221 
222 	/* -EIO all pending I/O */
223 	if (!IS_ERR(clp->cl_rpcclient))
224 		rpc_shutdown_client(clp->cl_rpcclient);
225 
226 	if (clp->cl_machine_cred != NULL)
227 		put_rpccred(clp->cl_machine_cred);
228 
229 	kfree(clp->cl_hostname);
230 	kfree(clp);
231 
232 	dprintk("<-- nfs_free_client()\n");
233 }
234 
235 /*
236  * Release a reference to a shared client record
237  */
238 void nfs_put_client(struct nfs_client *clp)
239 {
240 	if (!clp)
241 		return;
242 
243 	dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
244 
245 	if (atomic_dec_and_lock(&clp->cl_count, &nfs_client_lock)) {
246 		list_del(&clp->cl_share_link);
247 		spin_unlock(&nfs_client_lock);
248 
249 		BUG_ON(!list_empty(&clp->cl_superblocks));
250 
251 		nfs_free_client(clp);
252 	}
253 }
254 
255 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
256 /*
257  * Test if two ip6 socket addresses refer to the same socket by
258  * comparing relevant fields. The padding bytes specifically, are not
259  * compared. sin6_flowinfo is not compared because it only affects QoS
260  * and sin6_scope_id is only compared if the address is "link local"
261  * because "link local" addresses need only be unique to a specific
262  * link. Conversely, ordinary unicast addresses might have different
263  * sin6_scope_id.
264  *
265  * The caller should ensure both socket addresses are AF_INET6.
266  */
267 static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
268 				      const struct sockaddr *sa2)
269 {
270 	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
271 	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
272 
273 	if (ipv6_addr_scope(&sin1->sin6_addr) == IPV6_ADDR_SCOPE_LINKLOCAL &&
274 	    sin1->sin6_scope_id != sin2->sin6_scope_id)
275 		return 0;
276 
277 	return ipv6_addr_equal(&sin1->sin6_addr, &sin1->sin6_addr);
278 }
279 #else	/* !defined(CONFIG_IPV6) && !defined(CONFIG_IPV6_MODULE) */
280 static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
281 				      const struct sockaddr *sa2)
282 {
283 	return 0;
284 }
285 #endif
286 
287 /*
288  * Test if two ip4 socket addresses refer to the same socket, by
289  * comparing relevant fields. The padding bytes specifically, are
290  * not compared.
291  *
292  * The caller should ensure both socket addresses are AF_INET.
293  */
294 static int nfs_sockaddr_match_ipaddr4(const struct sockaddr *sa1,
295 				      const struct sockaddr *sa2)
296 {
297 	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
298 	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
299 
300 	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
301 }
302 
303 static int nfs_sockaddr_cmp_ip6(const struct sockaddr *sa1,
304 				const struct sockaddr *sa2)
305 {
306 	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
307 	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
308 
309 	return nfs_sockaddr_match_ipaddr6(sa1, sa2) &&
310 		(sin1->sin6_port == sin2->sin6_port);
311 }
312 
313 static int nfs_sockaddr_cmp_ip4(const struct sockaddr *sa1,
314 				const struct sockaddr *sa2)
315 {
316 	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
317 	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
318 
319 	return nfs_sockaddr_match_ipaddr4(sa1, sa2) &&
320 		(sin1->sin_port == sin2->sin_port);
321 }
322 
323 /*
324  * Test if two socket addresses represent the same actual socket,
325  * by comparing (only) relevant fields, excluding the port number.
326  */
327 static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
328 				     const struct sockaddr *sa2)
329 {
330 	if (sa1->sa_family != sa2->sa_family)
331 		return 0;
332 
333 	switch (sa1->sa_family) {
334 	case AF_INET:
335 		return nfs_sockaddr_match_ipaddr4(sa1, sa2);
336 	case AF_INET6:
337 		return nfs_sockaddr_match_ipaddr6(sa1, sa2);
338 	}
339 	return 0;
340 }
341 
342 /*
343  * Test if two socket addresses represent the same actual socket,
344  * by comparing (only) relevant fields, including the port number.
345  */
346 static int nfs_sockaddr_cmp(const struct sockaddr *sa1,
347 			    const struct sockaddr *sa2)
348 {
349 	if (sa1->sa_family != sa2->sa_family)
350 		return 0;
351 
352 	switch (sa1->sa_family) {
353 	case AF_INET:
354 		return nfs_sockaddr_cmp_ip4(sa1, sa2);
355 	case AF_INET6:
356 		return nfs_sockaddr_cmp_ip6(sa1, sa2);
357 	}
358 	return 0;
359 }
360 
361 /*
362  * Find a client by IP address and protocol version
363  * - returns NULL if no such client
364  */
365 struct nfs_client *nfs_find_client(const struct sockaddr *addr, u32 nfsversion)
366 {
367 	struct nfs_client *clp;
368 
369 	spin_lock(&nfs_client_lock);
370 	list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
371 		struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
372 
373 		/* Don't match clients that failed to initialise properly */
374 		if (!(clp->cl_cons_state == NFS_CS_READY ||
375 		      clp->cl_cons_state == NFS_CS_SESSION_INITING))
376 			continue;
377 
378 		/* Different NFS versions cannot share the same nfs_client */
379 		if (clp->rpc_ops->version != nfsversion)
380 			continue;
381 
382 		/* Match only the IP address, not the port number */
383 		if (!nfs_sockaddr_match_ipaddr(addr, clap))
384 			continue;
385 
386 		atomic_inc(&clp->cl_count);
387 		spin_unlock(&nfs_client_lock);
388 		return clp;
389 	}
390 	spin_unlock(&nfs_client_lock);
391 	return NULL;
392 }
393 
394 /*
395  * Find a client by IP address and protocol version
396  * - returns NULL if no such client
397  */
398 struct nfs_client *nfs_find_client_next(struct nfs_client *clp)
399 {
400 	struct sockaddr *sap = (struct sockaddr *)&clp->cl_addr;
401 	u32 nfsvers = clp->rpc_ops->version;
402 
403 	spin_lock(&nfs_client_lock);
404 	list_for_each_entry_continue(clp, &nfs_client_list, cl_share_link) {
405 		struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
406 
407 		/* Don't match clients that failed to initialise properly */
408 		if (clp->cl_cons_state != NFS_CS_READY)
409 			continue;
410 
411 		/* Different NFS versions cannot share the same nfs_client */
412 		if (clp->rpc_ops->version != nfsvers)
413 			continue;
414 
415 		/* Match only the IP address, not the port number */
416 		if (!nfs_sockaddr_match_ipaddr(sap, clap))
417 			continue;
418 
419 		atomic_inc(&clp->cl_count);
420 		spin_unlock(&nfs_client_lock);
421 		return clp;
422 	}
423 	spin_unlock(&nfs_client_lock);
424 	return NULL;
425 }
426 
427 /*
428  * Find an nfs_client on the list that matches the initialisation data
429  * that is supplied.
430  */
431 static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
432 {
433 	struct nfs_client *clp;
434 	const struct sockaddr *sap = data->addr;
435 
436 	list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
437 	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
438 		/* Don't match clients that failed to initialise properly */
439 		if (clp->cl_cons_state < 0)
440 			continue;
441 
442 		/* Different NFS versions cannot share the same nfs_client */
443 		if (clp->rpc_ops != data->rpc_ops)
444 			continue;
445 
446 		if (clp->cl_proto != data->proto)
447 			continue;
448 		/* Match nfsv4 minorversion */
449 		if (clp->cl_minorversion != data->minorversion)
450 			continue;
451 		/* Match the full socket address */
452 		if (!nfs_sockaddr_cmp(sap, clap))
453 			continue;
454 
455 		atomic_inc(&clp->cl_count);
456 		return clp;
457 	}
458 	return NULL;
459 }
460 
461 /*
462  * Look up a client by IP address and protocol version
463  * - creates a new record if one doesn't yet exist
464  */
465 static struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
466 {
467 	struct nfs_client *clp, *new = NULL;
468 	int error;
469 
470 	dprintk("--> nfs_get_client(%s,v%u)\n",
471 		cl_init->hostname ?: "", cl_init->rpc_ops->version);
472 
473 	/* see if the client already exists */
474 	do {
475 		spin_lock(&nfs_client_lock);
476 
477 		clp = nfs_match_client(cl_init);
478 		if (clp)
479 			goto found_client;
480 		if (new)
481 			goto install_client;
482 
483 		spin_unlock(&nfs_client_lock);
484 
485 		new = nfs_alloc_client(cl_init);
486 	} while (!IS_ERR(new));
487 
488 	dprintk("--> nfs_get_client() = %ld [failed]\n", PTR_ERR(new));
489 	return new;
490 
491 	/* install a new client and return with it unready */
492 install_client:
493 	clp = new;
494 	list_add(&clp->cl_share_link, &nfs_client_list);
495 	spin_unlock(&nfs_client_lock);
496 	dprintk("--> nfs_get_client() = %p [new]\n", clp);
497 	return clp;
498 
499 	/* found an existing client
500 	 * - make sure it's ready before returning
501 	 */
502 found_client:
503 	spin_unlock(&nfs_client_lock);
504 
505 	if (new)
506 		nfs_free_client(new);
507 
508 	error = wait_event_killable(nfs_client_active_wq,
509 				clp->cl_cons_state < NFS_CS_INITING);
510 	if (error < 0) {
511 		nfs_put_client(clp);
512 		return ERR_PTR(-ERESTARTSYS);
513 	}
514 
515 	if (clp->cl_cons_state < NFS_CS_READY) {
516 		error = clp->cl_cons_state;
517 		nfs_put_client(clp);
518 		return ERR_PTR(error);
519 	}
520 
521 	BUG_ON(clp->cl_cons_state != NFS_CS_READY);
522 
523 	dprintk("--> nfs_get_client() = %p [share]\n", clp);
524 	return clp;
525 }
526 
527 /*
528  * Mark a server as ready or failed
529  */
530 void nfs_mark_client_ready(struct nfs_client *clp, int state)
531 {
532 	clp->cl_cons_state = state;
533 	wake_up_all(&nfs_client_active_wq);
534 }
535 
536 /*
537  * With sessions, the client is not marked ready until after a
538  * successful EXCHANGE_ID and CREATE_SESSION.
539  *
540  * Map errors cl_cons_state errors to EPROTONOSUPPORT to indicate
541  * other versions of NFS can be tried.
542  */
543 int nfs4_check_client_ready(struct nfs_client *clp)
544 {
545 	if (!nfs4_has_session(clp))
546 		return 0;
547 	if (clp->cl_cons_state < NFS_CS_READY)
548 		return -EPROTONOSUPPORT;
549 	return 0;
550 }
551 
552 /*
553  * Initialise the timeout values for a connection
554  */
555 static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
556 				    unsigned int timeo, unsigned int retrans)
557 {
558 	to->to_initval = timeo * HZ / 10;
559 	to->to_retries = retrans;
560 
561 	switch (proto) {
562 	case XPRT_TRANSPORT_TCP:
563 	case XPRT_TRANSPORT_RDMA:
564 		if (to->to_retries == 0)
565 			to->to_retries = NFS_DEF_TCP_RETRANS;
566 		if (to->to_initval == 0)
567 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
568 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
569 			to->to_initval = NFS_MAX_TCP_TIMEOUT;
570 		to->to_increment = to->to_initval;
571 		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
572 		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
573 			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
574 		if (to->to_maxval < to->to_initval)
575 			to->to_maxval = to->to_initval;
576 		to->to_exponential = 0;
577 		break;
578 	case XPRT_TRANSPORT_UDP:
579 		if (to->to_retries == 0)
580 			to->to_retries = NFS_DEF_UDP_RETRANS;
581 		if (!to->to_initval)
582 			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
583 		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
584 			to->to_initval = NFS_MAX_UDP_TIMEOUT;
585 		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
586 		to->to_exponential = 1;
587 		break;
588 	default:
589 		BUG();
590 	}
591 }
592 
593 /*
594  * Create an RPC client handle
595  */
596 static int nfs_create_rpc_client(struct nfs_client *clp,
597 				 const struct rpc_timeout *timeparms,
598 				 rpc_authflavor_t flavor,
599 				 int discrtry, int noresvport)
600 {
601 	struct rpc_clnt		*clnt = NULL;
602 	struct rpc_create_args args = {
603 		.protocol	= clp->cl_proto,
604 		.address	= (struct sockaddr *)&clp->cl_addr,
605 		.addrsize	= clp->cl_addrlen,
606 		.timeout	= timeparms,
607 		.servername	= clp->cl_hostname,
608 		.program	= &nfs_program,
609 		.version	= clp->rpc_ops->version,
610 		.authflavor	= flavor,
611 	};
612 
613 	if (discrtry)
614 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
615 	if (noresvport)
616 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
617 
618 	if (!IS_ERR(clp->cl_rpcclient))
619 		return 0;
620 
621 	clnt = rpc_create(&args);
622 	if (IS_ERR(clnt)) {
623 		dprintk("%s: cannot create RPC client. Error = %ld\n",
624 				__func__, PTR_ERR(clnt));
625 		return PTR_ERR(clnt);
626 	}
627 
628 	clp->cl_rpcclient = clnt;
629 	return 0;
630 }
631 
632 /*
633  * Version 2 or 3 client destruction
634  */
635 static void nfs_destroy_server(struct nfs_server *server)
636 {
637 	if (!(server->flags & NFS_MOUNT_NONLM))
638 		nlmclnt_done(server->nlm_host);
639 }
640 
641 /*
642  * Version 2 or 3 lockd setup
643  */
644 static int nfs_start_lockd(struct nfs_server *server)
645 {
646 	struct nlm_host *host;
647 	struct nfs_client *clp = server->nfs_client;
648 	struct nlmclnt_initdata nlm_init = {
649 		.hostname	= clp->cl_hostname,
650 		.address	= (struct sockaddr *)&clp->cl_addr,
651 		.addrlen	= clp->cl_addrlen,
652 		.nfs_version	= clp->rpc_ops->version,
653 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
654 					1 : 0,
655 	};
656 
657 	if (nlm_init.nfs_version > 3)
658 		return 0;
659 	if (server->flags & NFS_MOUNT_NONLM)
660 		return 0;
661 
662 	switch (clp->cl_proto) {
663 		default:
664 			nlm_init.protocol = IPPROTO_TCP;
665 			break;
666 		case XPRT_TRANSPORT_UDP:
667 			nlm_init.protocol = IPPROTO_UDP;
668 	}
669 
670 	host = nlmclnt_init(&nlm_init);
671 	if (IS_ERR(host))
672 		return PTR_ERR(host);
673 
674 	server->nlm_host = host;
675 	server->destroy = nfs_destroy_server;
676 	return 0;
677 }
678 
679 /*
680  * Initialise an NFSv3 ACL client connection
681  */
682 #ifdef CONFIG_NFS_V3_ACL
683 static void nfs_init_server_aclclient(struct nfs_server *server)
684 {
685 	if (server->nfs_client->rpc_ops->version != 3)
686 		goto out_noacl;
687 	if (server->flags & NFS_MOUNT_NOACL)
688 		goto out_noacl;
689 
690 	server->client_acl = rpc_bind_new_program(server->client, &nfsacl_program, 3);
691 	if (IS_ERR(server->client_acl))
692 		goto out_noacl;
693 
694 	/* No errors! Assume that Sun nfsacls are supported */
695 	server->caps |= NFS_CAP_ACLS;
696 	return;
697 
698 out_noacl:
699 	server->caps &= ~NFS_CAP_ACLS;
700 }
701 #else
702 static inline void nfs_init_server_aclclient(struct nfs_server *server)
703 {
704 	server->flags &= ~NFS_MOUNT_NOACL;
705 	server->caps &= ~NFS_CAP_ACLS;
706 }
707 #endif
708 
709 /*
710  * Create a general RPC client
711  */
712 static int nfs_init_server_rpcclient(struct nfs_server *server,
713 		const struct rpc_timeout *timeo,
714 		rpc_authflavor_t pseudoflavour)
715 {
716 	struct nfs_client *clp = server->nfs_client;
717 
718 	server->client = rpc_clone_client(clp->cl_rpcclient);
719 	if (IS_ERR(server->client)) {
720 		dprintk("%s: couldn't create rpc_client!\n", __func__);
721 		return PTR_ERR(server->client);
722 	}
723 
724 	memcpy(&server->client->cl_timeout_default,
725 			timeo,
726 			sizeof(server->client->cl_timeout_default));
727 	server->client->cl_timeout = &server->client->cl_timeout_default;
728 
729 	if (pseudoflavour != clp->cl_rpcclient->cl_auth->au_flavor) {
730 		struct rpc_auth *auth;
731 
732 		auth = rpcauth_create(pseudoflavour, server->client);
733 		if (IS_ERR(auth)) {
734 			dprintk("%s: couldn't create credcache!\n", __func__);
735 			return PTR_ERR(auth);
736 		}
737 	}
738 	server->client->cl_softrtry = 0;
739 	if (server->flags & NFS_MOUNT_SOFT)
740 		server->client->cl_softrtry = 1;
741 
742 	return 0;
743 }
744 
745 /*
746  * Initialise an NFS2 or NFS3 client
747  */
748 static int nfs_init_client(struct nfs_client *clp,
749 			   const struct rpc_timeout *timeparms,
750 			   const struct nfs_parsed_mount_data *data)
751 {
752 	int error;
753 
754 	if (clp->cl_cons_state == NFS_CS_READY) {
755 		/* the client is already initialised */
756 		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
757 		return 0;
758 	}
759 
760 	/*
761 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
762 	 * - RFC 2623, sec 2.3.2
763 	 */
764 	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX,
765 				      0, data->flags & NFS_MOUNT_NORESVPORT);
766 	if (error < 0)
767 		goto error;
768 	nfs_mark_client_ready(clp, NFS_CS_READY);
769 	return 0;
770 
771 error:
772 	nfs_mark_client_ready(clp, error);
773 	dprintk("<-- nfs_init_client() = xerror %d\n", error);
774 	return error;
775 }
776 
777 /*
778  * Create a version 2 or 3 client
779  */
780 static int nfs_init_server(struct nfs_server *server,
781 			   const struct nfs_parsed_mount_data *data)
782 {
783 	struct nfs_client_initdata cl_init = {
784 		.hostname = data->nfs_server.hostname,
785 		.addr = (const struct sockaddr *)&data->nfs_server.address,
786 		.addrlen = data->nfs_server.addrlen,
787 		.rpc_ops = &nfs_v2_clientops,
788 		.proto = data->nfs_server.protocol,
789 	};
790 	struct rpc_timeout timeparms;
791 	struct nfs_client *clp;
792 	int error;
793 
794 	dprintk("--> nfs_init_server()\n");
795 
796 #ifdef CONFIG_NFS_V3
797 	if (data->version == 3)
798 		cl_init.rpc_ops = &nfs_v3_clientops;
799 #endif
800 
801 	/* Allocate or find a client reference we can use */
802 	clp = nfs_get_client(&cl_init);
803 	if (IS_ERR(clp)) {
804 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
805 		return PTR_ERR(clp);
806 	}
807 
808 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
809 			data->timeo, data->retrans);
810 	error = nfs_init_client(clp, &timeparms, data);
811 	if (error < 0)
812 		goto error;
813 
814 	server->nfs_client = clp;
815 
816 	/* Initialise the client representation from the mount data */
817 	server->flags = data->flags;
818 	server->options = data->options;
819 	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
820 		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
821 		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
822 
823 	if (data->rsize)
824 		server->rsize = nfs_block_size(data->rsize, NULL);
825 	if (data->wsize)
826 		server->wsize = nfs_block_size(data->wsize, NULL);
827 
828 	server->acregmin = data->acregmin * HZ;
829 	server->acregmax = data->acregmax * HZ;
830 	server->acdirmin = data->acdirmin * HZ;
831 	server->acdirmax = data->acdirmax * HZ;
832 
833 	/* Start lockd here, before we might error out */
834 	error = nfs_start_lockd(server);
835 	if (error < 0)
836 		goto error;
837 
838 	server->port = data->nfs_server.port;
839 
840 	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
841 	if (error < 0)
842 		goto error;
843 
844 	/* Preserve the values of mount_server-related mount options */
845 	if (data->mount_server.addrlen) {
846 		memcpy(&server->mountd_address, &data->mount_server.address,
847 			data->mount_server.addrlen);
848 		server->mountd_addrlen = data->mount_server.addrlen;
849 	}
850 	server->mountd_version = data->mount_server.version;
851 	server->mountd_port = data->mount_server.port;
852 	server->mountd_protocol = data->mount_server.protocol;
853 
854 	server->namelen  = data->namlen;
855 	/* Create a client RPC handle for the NFSv3 ACL management interface */
856 	nfs_init_server_aclclient(server);
857 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
858 	return 0;
859 
860 error:
861 	server->nfs_client = NULL;
862 	nfs_put_client(clp);
863 	dprintk("<-- nfs_init_server() = xerror %d\n", error);
864 	return error;
865 }
866 
867 /*
868  * Load up the server record from information gained in an fsinfo record
869  */
870 static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo *fsinfo)
871 {
872 	unsigned long max_rpc_payload;
873 
874 	/* Work out a lot of parameters */
875 	if (server->rsize == 0)
876 		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
877 	if (server->wsize == 0)
878 		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
879 
880 	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
881 		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
882 	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
883 		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
884 
885 	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
886 	if (server->rsize > max_rpc_payload)
887 		server->rsize = max_rpc_payload;
888 	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
889 		server->rsize = NFS_MAX_FILE_IO_SIZE;
890 	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
891 
892 	server->backing_dev_info.name = "nfs";
893 	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
894 
895 	if (server->wsize > max_rpc_payload)
896 		server->wsize = max_rpc_payload;
897 	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
898 		server->wsize = NFS_MAX_FILE_IO_SIZE;
899 	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
900 	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
901 
902 	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
903 	if (server->dtsize > PAGE_CACHE_SIZE)
904 		server->dtsize = PAGE_CACHE_SIZE;
905 	if (server->dtsize > server->rsize)
906 		server->dtsize = server->rsize;
907 
908 	if (server->flags & NFS_MOUNT_NOAC) {
909 		server->acregmin = server->acregmax = 0;
910 		server->acdirmin = server->acdirmax = 0;
911 	}
912 
913 	server->maxfilesize = fsinfo->maxfilesize;
914 
915 	/* We're airborne Set socket buffersize */
916 	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
917 }
918 
919 /*
920  * Probe filesystem information, including the FSID on v2/v3
921  */
922 static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
923 {
924 	struct nfs_fsinfo fsinfo;
925 	struct nfs_client *clp = server->nfs_client;
926 	int error;
927 
928 	dprintk("--> nfs_probe_fsinfo()\n");
929 
930 	if (clp->rpc_ops->set_capabilities != NULL) {
931 		error = clp->rpc_ops->set_capabilities(server, mntfh);
932 		if (error < 0)
933 			goto out_error;
934 	}
935 
936 	fsinfo.fattr = fattr;
937 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
938 	if (error < 0)
939 		goto out_error;
940 
941 	nfs_server_set_fsinfo(server, &fsinfo);
942 
943 	/* Get some general file system info */
944 	if (server->namelen == 0) {
945 		struct nfs_pathconf pathinfo;
946 
947 		pathinfo.fattr = fattr;
948 		nfs_fattr_init(fattr);
949 
950 		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
951 			server->namelen = pathinfo.max_namelen;
952 	}
953 
954 	dprintk("<-- nfs_probe_fsinfo() = 0\n");
955 	return 0;
956 
957 out_error:
958 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
959 	return error;
960 }
961 
962 /*
963  * Copy useful information when duplicating a server record
964  */
965 static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
966 {
967 	target->flags = source->flags;
968 	target->rsize = source->rsize;
969 	target->wsize = source->wsize;
970 	target->acregmin = source->acregmin;
971 	target->acregmax = source->acregmax;
972 	target->acdirmin = source->acdirmin;
973 	target->acdirmax = source->acdirmax;
974 	target->caps = source->caps;
975 	target->options = source->options;
976 }
977 
978 /*
979  * Allocate and initialise a server record
980  */
981 static struct nfs_server *nfs_alloc_server(void)
982 {
983 	struct nfs_server *server;
984 
985 	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
986 	if (!server)
987 		return NULL;
988 
989 	server->client = server->client_acl = ERR_PTR(-EINVAL);
990 
991 	/* Zero out the NFS state stuff */
992 	INIT_LIST_HEAD(&server->client_link);
993 	INIT_LIST_HEAD(&server->master_link);
994 
995 	atomic_set(&server->active, 0);
996 
997 	server->io_stats = nfs_alloc_iostats();
998 	if (!server->io_stats) {
999 		kfree(server);
1000 		return NULL;
1001 	}
1002 
1003 	if (bdi_init(&server->backing_dev_info)) {
1004 		nfs_free_iostats(server->io_stats);
1005 		kfree(server);
1006 		return NULL;
1007 	}
1008 
1009 	return server;
1010 }
1011 
1012 /*
1013  * Free up a server record
1014  */
1015 void nfs_free_server(struct nfs_server *server)
1016 {
1017 	dprintk("--> nfs_free_server()\n");
1018 
1019 	spin_lock(&nfs_client_lock);
1020 	list_del(&server->client_link);
1021 	list_del(&server->master_link);
1022 	spin_unlock(&nfs_client_lock);
1023 
1024 	if (server->destroy != NULL)
1025 		server->destroy(server);
1026 
1027 	if (!IS_ERR(server->client_acl))
1028 		rpc_shutdown_client(server->client_acl);
1029 	if (!IS_ERR(server->client))
1030 		rpc_shutdown_client(server->client);
1031 
1032 	nfs_put_client(server->nfs_client);
1033 
1034 	nfs_free_iostats(server->io_stats);
1035 	bdi_destroy(&server->backing_dev_info);
1036 	kfree(server);
1037 	nfs_release_automount_timer();
1038 	dprintk("<-- nfs_free_server()\n");
1039 }
1040 
1041 /*
1042  * Create a version 2 or 3 volume record
1043  * - keyed on server and FSID
1044  */
1045 struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
1046 				     struct nfs_fh *mntfh)
1047 {
1048 	struct nfs_server *server;
1049 	struct nfs_fattr *fattr;
1050 	int error;
1051 
1052 	server = nfs_alloc_server();
1053 	if (!server)
1054 		return ERR_PTR(-ENOMEM);
1055 
1056 	error = -ENOMEM;
1057 	fattr = nfs_alloc_fattr();
1058 	if (fattr == NULL)
1059 		goto error;
1060 
1061 	/* Get a client representation */
1062 	error = nfs_init_server(server, data);
1063 	if (error < 0)
1064 		goto error;
1065 
1066 	BUG_ON(!server->nfs_client);
1067 	BUG_ON(!server->nfs_client->rpc_ops);
1068 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1069 
1070 	/* Probe the root fh to retrieve its FSID */
1071 	error = nfs_probe_fsinfo(server, mntfh, fattr);
1072 	if (error < 0)
1073 		goto error;
1074 	if (server->nfs_client->rpc_ops->version == 3) {
1075 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
1076 			server->namelen = NFS3_MAXNAMLEN;
1077 		if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
1078 			server->caps |= NFS_CAP_READDIRPLUS;
1079 	} else {
1080 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
1081 			server->namelen = NFS2_MAXNAMLEN;
1082 	}
1083 
1084 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
1085 		error = server->nfs_client->rpc_ops->getattr(server, mntfh, fattr);
1086 		if (error < 0) {
1087 			dprintk("nfs_create_server: getattr error = %d\n", -error);
1088 			goto error;
1089 		}
1090 	}
1091 	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1092 
1093 	dprintk("Server FSID: %llx:%llx\n",
1094 		(unsigned long long) server->fsid.major,
1095 		(unsigned long long) server->fsid.minor);
1096 
1097 	spin_lock(&nfs_client_lock);
1098 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1099 	list_add_tail(&server->master_link, &nfs_volume_list);
1100 	spin_unlock(&nfs_client_lock);
1101 
1102 	server->mount_time = jiffies;
1103 	nfs_free_fattr(fattr);
1104 	return server;
1105 
1106 error:
1107 	nfs_free_fattr(fattr);
1108 	nfs_free_server(server);
1109 	return ERR_PTR(error);
1110 }
1111 
1112 #ifdef CONFIG_NFS_V4
1113 /*
1114  * Initialize the NFS4 callback service
1115  */
1116 static int nfs4_init_callback(struct nfs_client *clp)
1117 {
1118 	int error;
1119 
1120 	if (clp->rpc_ops->version == 4) {
1121 		if (nfs4_has_session(clp)) {
1122 			error = xprt_setup_backchannel(
1123 						clp->cl_rpcclient->cl_xprt,
1124 						NFS41_BC_MIN_CALLBACKS);
1125 			if (error < 0)
1126 				return error;
1127 		}
1128 
1129 		error = nfs_callback_up(clp->cl_minorversion,
1130 					clp->cl_rpcclient->cl_xprt);
1131 		if (error < 0) {
1132 			dprintk("%s: failed to start callback. Error = %d\n",
1133 				__func__, error);
1134 			return error;
1135 		}
1136 		__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
1137 	}
1138 	return 0;
1139 }
1140 
1141 /*
1142  * Initialize the minor version specific parts of an NFS4 client record
1143  */
1144 static int nfs4_init_client_minor_version(struct nfs_client *clp)
1145 {
1146 	clp->cl_call_sync = _nfs4_call_sync;
1147 
1148 #if defined(CONFIG_NFS_V4_1)
1149 	if (clp->cl_minorversion) {
1150 		struct nfs4_session *session = NULL;
1151 		/*
1152 		 * Create the session and mark it expired.
1153 		 * When a SEQUENCE operation encounters the expired session
1154 		 * it will do session recovery to initialize it.
1155 		 */
1156 		session = nfs4_alloc_session(clp);
1157 		if (!session)
1158 			return -ENOMEM;
1159 
1160 		clp->cl_session = session;
1161 		clp->cl_call_sync = _nfs4_call_sync_session;
1162 	}
1163 #endif /* CONFIG_NFS_V4_1 */
1164 
1165 	return nfs4_init_callback(clp);
1166 }
1167 
1168 /*
1169  * Initialise an NFS4 client record
1170  */
1171 static int nfs4_init_client(struct nfs_client *clp,
1172 		const struct rpc_timeout *timeparms,
1173 		const char *ip_addr,
1174 		rpc_authflavor_t authflavour,
1175 		int flags)
1176 {
1177 	int error;
1178 
1179 	if (clp->cl_cons_state == NFS_CS_READY) {
1180 		/* the client is initialised already */
1181 		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
1182 		return 0;
1183 	}
1184 
1185 	/* Check NFS protocol revision and initialize RPC op vector */
1186 	clp->rpc_ops = &nfs_v4_clientops;
1187 
1188 	error = nfs_create_rpc_client(clp, timeparms, authflavour,
1189 				      1, flags & NFS_MOUNT_NORESVPORT);
1190 	if (error < 0)
1191 		goto error;
1192 	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
1193 
1194 	error = nfs_idmap_new(clp);
1195 	if (error < 0) {
1196 		dprintk("%s: failed to create idmapper. Error = %d\n",
1197 			__func__, error);
1198 		goto error;
1199 	}
1200 	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
1201 
1202 	error = nfs4_init_client_minor_version(clp);
1203 	if (error < 0)
1204 		goto error;
1205 
1206 	if (!nfs4_has_session(clp))
1207 		nfs_mark_client_ready(clp, NFS_CS_READY);
1208 	return 0;
1209 
1210 error:
1211 	nfs_mark_client_ready(clp, error);
1212 	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
1213 	return error;
1214 }
1215 
1216 /*
1217  * Set up an NFS4 client
1218  */
1219 static int nfs4_set_client(struct nfs_server *server,
1220 		const char *hostname,
1221 		const struct sockaddr *addr,
1222 		const size_t addrlen,
1223 		const char *ip_addr,
1224 		rpc_authflavor_t authflavour,
1225 		int proto, const struct rpc_timeout *timeparms,
1226 		u32 minorversion)
1227 {
1228 	struct nfs_client_initdata cl_init = {
1229 		.hostname = hostname,
1230 		.addr = addr,
1231 		.addrlen = addrlen,
1232 		.rpc_ops = &nfs_v4_clientops,
1233 		.proto = proto,
1234 		.minorversion = minorversion,
1235 	};
1236 	struct nfs_client *clp;
1237 	int error;
1238 
1239 	dprintk("--> nfs4_set_client()\n");
1240 
1241 	/* Allocate or find a client reference we can use */
1242 	clp = nfs_get_client(&cl_init);
1243 	if (IS_ERR(clp)) {
1244 		error = PTR_ERR(clp);
1245 		goto error;
1246 	}
1247 	error = nfs4_init_client(clp, timeparms, ip_addr, authflavour,
1248 					server->flags);
1249 	if (error < 0)
1250 		goto error_put;
1251 
1252 	server->nfs_client = clp;
1253 	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
1254 	return 0;
1255 
1256 error_put:
1257 	nfs_put_client(clp);
1258 error:
1259 	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
1260 	return error;
1261 }
1262 
1263 
1264 /*
1265  * Session has been established, and the client marked ready.
1266  * Set the mount rsize and wsize with negotiated fore channel
1267  * attributes which will be bound checked in nfs_server_set_fsinfo.
1268  */
1269 static void nfs4_session_set_rwsize(struct nfs_server *server)
1270 {
1271 #ifdef CONFIG_NFS_V4_1
1272 	struct nfs4_session *sess;
1273 	u32 server_resp_sz;
1274 	u32 server_rqst_sz;
1275 
1276 	if (!nfs4_has_session(server->nfs_client))
1277 		return;
1278 	sess = server->nfs_client->cl_session;
1279 	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
1280 	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
1281 
1282 	if (server->rsize > server_resp_sz)
1283 		server->rsize = server_resp_sz;
1284 	if (server->wsize > server_rqst_sz)
1285 		server->wsize = server_rqst_sz;
1286 #endif /* CONFIG_NFS_V4_1 */
1287 }
1288 
1289 /*
1290  * Create a version 4 volume record
1291  */
1292 static int nfs4_init_server(struct nfs_server *server,
1293 		const struct nfs_parsed_mount_data *data)
1294 {
1295 	struct rpc_timeout timeparms;
1296 	int error;
1297 
1298 	dprintk("--> nfs4_init_server()\n");
1299 
1300 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1301 			data->timeo, data->retrans);
1302 
1303 	/* Initialise the client representation from the mount data */
1304 	server->flags = data->flags;
1305 	server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|
1306 		NFS_CAP_POSIX_LOCK;
1307 	server->options = data->options;
1308 
1309 	/* Get a client record */
1310 	error = nfs4_set_client(server,
1311 			data->nfs_server.hostname,
1312 			(const struct sockaddr *)&data->nfs_server.address,
1313 			data->nfs_server.addrlen,
1314 			data->client_address,
1315 			data->auth_flavors[0],
1316 			data->nfs_server.protocol,
1317 			&timeparms,
1318 			data->minorversion);
1319 	if (error < 0)
1320 		goto error;
1321 
1322 	if (data->rsize)
1323 		server->rsize = nfs_block_size(data->rsize, NULL);
1324 	if (data->wsize)
1325 		server->wsize = nfs_block_size(data->wsize, NULL);
1326 
1327 	server->acregmin = data->acregmin * HZ;
1328 	server->acregmax = data->acregmax * HZ;
1329 	server->acdirmin = data->acdirmin * HZ;
1330 	server->acdirmax = data->acdirmax * HZ;
1331 
1332 	server->port = data->nfs_server.port;
1333 
1334 	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
1335 
1336 error:
1337 	/* Done */
1338 	dprintk("<-- nfs4_init_server() = %d\n", error);
1339 	return error;
1340 }
1341 
1342 /*
1343  * Create a version 4 volume record
1344  * - keyed on server and FSID
1345  */
1346 struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1347 				      struct nfs_fh *mntfh)
1348 {
1349 	struct nfs_fattr *fattr;
1350 	struct nfs_server *server;
1351 	int error;
1352 
1353 	dprintk("--> nfs4_create_server()\n");
1354 
1355 	server = nfs_alloc_server();
1356 	if (!server)
1357 		return ERR_PTR(-ENOMEM);
1358 
1359 	error = -ENOMEM;
1360 	fattr = nfs_alloc_fattr();
1361 	if (fattr == NULL)
1362 		goto error;
1363 
1364 	/* set up the general RPC client */
1365 	error = nfs4_init_server(server, data);
1366 	if (error < 0)
1367 		goto error;
1368 
1369 	BUG_ON(!server->nfs_client);
1370 	BUG_ON(!server->nfs_client->rpc_ops);
1371 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1372 
1373 	error = nfs4_init_session(server);
1374 	if (error < 0)
1375 		goto error;
1376 
1377 	/* Probe the root fh to retrieve its FSID */
1378 	error = nfs4_get_rootfh(server, mntfh);
1379 	if (error < 0)
1380 		goto error;
1381 
1382 	dprintk("Server FSID: %llx:%llx\n",
1383 		(unsigned long long) server->fsid.major,
1384 		(unsigned long long) server->fsid.minor);
1385 	dprintk("Mount FH: %d\n", mntfh->size);
1386 
1387 	nfs4_session_set_rwsize(server);
1388 
1389 	error = nfs_probe_fsinfo(server, mntfh, fattr);
1390 	if (error < 0)
1391 		goto error;
1392 
1393 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1394 		server->namelen = NFS4_MAXNAMLEN;
1395 
1396 	spin_lock(&nfs_client_lock);
1397 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1398 	list_add_tail(&server->master_link, &nfs_volume_list);
1399 	spin_unlock(&nfs_client_lock);
1400 
1401 	server->mount_time = jiffies;
1402 	dprintk("<-- nfs4_create_server() = %p\n", server);
1403 	nfs_free_fattr(fattr);
1404 	return server;
1405 
1406 error:
1407 	nfs_free_fattr(fattr);
1408 	nfs_free_server(server);
1409 	dprintk("<-- nfs4_create_server() = error %d\n", error);
1410 	return ERR_PTR(error);
1411 }
1412 
1413 /*
1414  * Create an NFS4 referral server record
1415  */
1416 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1417 					       struct nfs_fh *mntfh)
1418 {
1419 	struct nfs_client *parent_client;
1420 	struct nfs_server *server, *parent_server;
1421 	struct nfs_fattr *fattr;
1422 	int error;
1423 
1424 	dprintk("--> nfs4_create_referral_server()\n");
1425 
1426 	server = nfs_alloc_server();
1427 	if (!server)
1428 		return ERR_PTR(-ENOMEM);
1429 
1430 	error = -ENOMEM;
1431 	fattr = nfs_alloc_fattr();
1432 	if (fattr == NULL)
1433 		goto error;
1434 
1435 	parent_server = NFS_SB(data->sb);
1436 	parent_client = parent_server->nfs_client;
1437 
1438 	/* Initialise the client representation from the parent server */
1439 	nfs_server_copy_userdata(server, parent_server);
1440 	server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR;
1441 
1442 	/* Get a client representation.
1443 	 * Note: NFSv4 always uses TCP, */
1444 	error = nfs4_set_client(server, data->hostname,
1445 				data->addr,
1446 				data->addrlen,
1447 				parent_client->cl_ipaddr,
1448 				data->authflavor,
1449 				parent_server->client->cl_xprt->prot,
1450 				parent_server->client->cl_timeout,
1451 				parent_client->cl_minorversion);
1452 	if (error < 0)
1453 		goto error;
1454 
1455 	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1456 	if (error < 0)
1457 		goto error;
1458 
1459 	BUG_ON(!server->nfs_client);
1460 	BUG_ON(!server->nfs_client->rpc_ops);
1461 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1462 
1463 	/* Probe the root fh to retrieve its FSID and filehandle */
1464 	error = nfs4_get_rootfh(server, mntfh);
1465 	if (error < 0)
1466 		goto error;
1467 
1468 	/* probe the filesystem info for this server filesystem */
1469 	error = nfs_probe_fsinfo(server, mntfh, fattr);
1470 	if (error < 0)
1471 		goto error;
1472 
1473 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1474 		server->namelen = NFS4_MAXNAMLEN;
1475 
1476 	dprintk("Referral FSID: %llx:%llx\n",
1477 		(unsigned long long) server->fsid.major,
1478 		(unsigned long long) server->fsid.minor);
1479 
1480 	spin_lock(&nfs_client_lock);
1481 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1482 	list_add_tail(&server->master_link, &nfs_volume_list);
1483 	spin_unlock(&nfs_client_lock);
1484 
1485 	server->mount_time = jiffies;
1486 
1487 	nfs_free_fattr(fattr);
1488 	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1489 	return server;
1490 
1491 error:
1492 	nfs_free_fattr(fattr);
1493 	nfs_free_server(server);
1494 	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1495 	return ERR_PTR(error);
1496 }
1497 
1498 #endif /* CONFIG_NFS_V4 */
1499 
1500 /*
1501  * Clone an NFS2, NFS3 or NFS4 server record
1502  */
1503 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1504 				    struct nfs_fh *fh,
1505 				    struct nfs_fattr *fattr)
1506 {
1507 	struct nfs_server *server;
1508 	struct nfs_fattr *fattr_fsinfo;
1509 	int error;
1510 
1511 	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1512 		(unsigned long long) fattr->fsid.major,
1513 		(unsigned long long) fattr->fsid.minor);
1514 
1515 	server = nfs_alloc_server();
1516 	if (!server)
1517 		return ERR_PTR(-ENOMEM);
1518 
1519 	error = -ENOMEM;
1520 	fattr_fsinfo = nfs_alloc_fattr();
1521 	if (fattr_fsinfo == NULL)
1522 		goto out_free_server;
1523 
1524 	/* Copy data from the source */
1525 	server->nfs_client = source->nfs_client;
1526 	atomic_inc(&server->nfs_client->cl_count);
1527 	nfs_server_copy_userdata(server, source);
1528 
1529 	server->fsid = fattr->fsid;
1530 
1531 	error = nfs_init_server_rpcclient(server,
1532 			source->client->cl_timeout,
1533 			source->client->cl_auth->au_flavor);
1534 	if (error < 0)
1535 		goto out_free_server;
1536 	if (!IS_ERR(source->client_acl))
1537 		nfs_init_server_aclclient(server);
1538 
1539 	/* probe the filesystem info for this server filesystem */
1540 	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1541 	if (error < 0)
1542 		goto out_free_server;
1543 
1544 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1545 		server->namelen = NFS4_MAXNAMLEN;
1546 
1547 	dprintk("Cloned FSID: %llx:%llx\n",
1548 		(unsigned long long) server->fsid.major,
1549 		(unsigned long long) server->fsid.minor);
1550 
1551 	error = nfs_start_lockd(server);
1552 	if (error < 0)
1553 		goto out_free_server;
1554 
1555 	spin_lock(&nfs_client_lock);
1556 	list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1557 	list_add_tail(&server->master_link, &nfs_volume_list);
1558 	spin_unlock(&nfs_client_lock);
1559 
1560 	server->mount_time = jiffies;
1561 
1562 	nfs_free_fattr(fattr_fsinfo);
1563 	dprintk("<-- nfs_clone_server() = %p\n", server);
1564 	return server;
1565 
1566 out_free_server:
1567 	nfs_free_fattr(fattr_fsinfo);
1568 	nfs_free_server(server);
1569 	dprintk("<-- nfs_clone_server() = error %d\n", error);
1570 	return ERR_PTR(error);
1571 }
1572 
1573 #ifdef CONFIG_PROC_FS
1574 static struct proc_dir_entry *proc_fs_nfs;
1575 
1576 static int nfs_server_list_open(struct inode *inode, struct file *file);
1577 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1578 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1579 static void nfs_server_list_stop(struct seq_file *p, void *v);
1580 static int nfs_server_list_show(struct seq_file *m, void *v);
1581 
1582 static const struct seq_operations nfs_server_list_ops = {
1583 	.start	= nfs_server_list_start,
1584 	.next	= nfs_server_list_next,
1585 	.stop	= nfs_server_list_stop,
1586 	.show	= nfs_server_list_show,
1587 };
1588 
1589 static const struct file_operations nfs_server_list_fops = {
1590 	.open		= nfs_server_list_open,
1591 	.read		= seq_read,
1592 	.llseek		= seq_lseek,
1593 	.release	= seq_release,
1594 	.owner		= THIS_MODULE,
1595 };
1596 
1597 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1598 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1599 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1600 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1601 static int nfs_volume_list_show(struct seq_file *m, void *v);
1602 
1603 static const struct seq_operations nfs_volume_list_ops = {
1604 	.start	= nfs_volume_list_start,
1605 	.next	= nfs_volume_list_next,
1606 	.stop	= nfs_volume_list_stop,
1607 	.show	= nfs_volume_list_show,
1608 };
1609 
1610 static const struct file_operations nfs_volume_list_fops = {
1611 	.open		= nfs_volume_list_open,
1612 	.read		= seq_read,
1613 	.llseek		= seq_lseek,
1614 	.release	= seq_release,
1615 	.owner		= THIS_MODULE,
1616 };
1617 
1618 /*
1619  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1620  * we're dealing
1621  */
1622 static int nfs_server_list_open(struct inode *inode, struct file *file)
1623 {
1624 	struct seq_file *m;
1625 	int ret;
1626 
1627 	ret = seq_open(file, &nfs_server_list_ops);
1628 	if (ret < 0)
1629 		return ret;
1630 
1631 	m = file->private_data;
1632 	m->private = PDE(inode)->data;
1633 
1634 	return 0;
1635 }
1636 
1637 /*
1638  * set up the iterator to start reading from the server list and return the first item
1639  */
1640 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1641 {
1642 	/* lock the list against modification */
1643 	spin_lock(&nfs_client_lock);
1644 	return seq_list_start_head(&nfs_client_list, *_pos);
1645 }
1646 
1647 /*
1648  * move to next server
1649  */
1650 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1651 {
1652 	return seq_list_next(v, &nfs_client_list, pos);
1653 }
1654 
1655 /*
1656  * clean up after reading from the transports list
1657  */
1658 static void nfs_server_list_stop(struct seq_file *p, void *v)
1659 {
1660 	spin_unlock(&nfs_client_lock);
1661 }
1662 
1663 /*
1664  * display a header line followed by a load of call lines
1665  */
1666 static int nfs_server_list_show(struct seq_file *m, void *v)
1667 {
1668 	struct nfs_client *clp;
1669 
1670 	/* display header on line 1 */
1671 	if (v == &nfs_client_list) {
1672 		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1673 		return 0;
1674 	}
1675 
1676 	/* display one transport per line on subsequent lines */
1677 	clp = list_entry(v, struct nfs_client, cl_share_link);
1678 
1679 	seq_printf(m, "v%u %s %s %3d %s\n",
1680 		   clp->rpc_ops->version,
1681 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1682 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1683 		   atomic_read(&clp->cl_count),
1684 		   clp->cl_hostname);
1685 
1686 	return 0;
1687 }
1688 
1689 /*
1690  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1691  */
1692 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1693 {
1694 	struct seq_file *m;
1695 	int ret;
1696 
1697 	ret = seq_open(file, &nfs_volume_list_ops);
1698 	if (ret < 0)
1699 		return ret;
1700 
1701 	m = file->private_data;
1702 	m->private = PDE(inode)->data;
1703 
1704 	return 0;
1705 }
1706 
1707 /*
1708  * set up the iterator to start reading from the volume list and return the first item
1709  */
1710 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1711 {
1712 	/* lock the list against modification */
1713 	spin_lock(&nfs_client_lock);
1714 	return seq_list_start_head(&nfs_volume_list, *_pos);
1715 }
1716 
1717 /*
1718  * move to next volume
1719  */
1720 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1721 {
1722 	return seq_list_next(v, &nfs_volume_list, pos);
1723 }
1724 
1725 /*
1726  * clean up after reading from the transports list
1727  */
1728 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1729 {
1730 	spin_unlock(&nfs_client_lock);
1731 }
1732 
1733 /*
1734  * display a header line followed by a load of call lines
1735  */
1736 static int nfs_volume_list_show(struct seq_file *m, void *v)
1737 {
1738 	struct nfs_server *server;
1739 	struct nfs_client *clp;
1740 	char dev[8], fsid[17];
1741 
1742 	/* display header on line 1 */
1743 	if (v == &nfs_volume_list) {
1744 		seq_puts(m, "NV SERVER   PORT DEV     FSID              FSC\n");
1745 		return 0;
1746 	}
1747 	/* display one transport per line on subsequent lines */
1748 	server = list_entry(v, struct nfs_server, master_link);
1749 	clp = server->nfs_client;
1750 
1751 	snprintf(dev, 8, "%u:%u",
1752 		 MAJOR(server->s_dev), MINOR(server->s_dev));
1753 
1754 	snprintf(fsid, 17, "%llx:%llx",
1755 		 (unsigned long long) server->fsid.major,
1756 		 (unsigned long long) server->fsid.minor);
1757 
1758 	seq_printf(m, "v%u %s %s %-7s %-17s %s\n",
1759 		   clp->rpc_ops->version,
1760 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1761 		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1762 		   dev,
1763 		   fsid,
1764 		   nfs_server_fscache_state(server));
1765 
1766 	return 0;
1767 }
1768 
1769 /*
1770  * initialise the /proc/fs/nfsfs/ directory
1771  */
1772 int __init nfs_fs_proc_init(void)
1773 {
1774 	struct proc_dir_entry *p;
1775 
1776 	proc_fs_nfs = proc_mkdir("fs/nfsfs", NULL);
1777 	if (!proc_fs_nfs)
1778 		goto error_0;
1779 
1780 	/* a file of servers with which we're dealing */
1781 	p = proc_create("servers", S_IFREG|S_IRUGO,
1782 			proc_fs_nfs, &nfs_server_list_fops);
1783 	if (!p)
1784 		goto error_1;
1785 
1786 	/* a file of volumes that we have mounted */
1787 	p = proc_create("volumes", S_IFREG|S_IRUGO,
1788 			proc_fs_nfs, &nfs_volume_list_fops);
1789 	if (!p)
1790 		goto error_2;
1791 	return 0;
1792 
1793 error_2:
1794 	remove_proc_entry("servers", proc_fs_nfs);
1795 error_1:
1796 	remove_proc_entry("fs/nfsfs", NULL);
1797 error_0:
1798 	return -ENOMEM;
1799 }
1800 
1801 /*
1802  * clean up the /proc/fs/nfsfs/ directory
1803  */
1804 void nfs_fs_proc_exit(void)
1805 {
1806 	remove_proc_entry("volumes", proc_fs_nfs);
1807 	remove_proc_entry("servers", proc_fs_nfs);
1808 	remove_proc_entry("fs/nfsfs", NULL);
1809 }
1810 
1811 #endif /* CONFIG_PROC_FS */
1812