xref: /openbmc/linux/fs/nfs/nfs4client.c (revision 232b0b08)
1 /*
2  * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
3  * Written by David Howells (dhowells@redhat.com)
4  */
5 #include <linux/module.h>
6 #include <linux/nfs_fs.h>
7 #include <linux/nfs_mount.h>
8 #include <linux/sunrpc/addr.h>
9 #include <linux/sunrpc/auth.h>
10 #include <linux/sunrpc/xprt.h>
11 #include <linux/sunrpc/bc_xprt.h>
12 #include <linux/sunrpc/rpc_pipe_fs.h>
13 #include "internal.h"
14 #include "callback.h"
15 #include "delegation.h"
16 #include "nfs4session.h"
17 #include "nfs4idmap.h"
18 #include "pnfs.h"
19 #include "netns.h"
20 
21 #define NFSDBG_FACILITY		NFSDBG_CLIENT
22 
23 /*
24  * Get a unique NFSv4.0 callback identifier which will be used
25  * by the V4.0 callback service to lookup the nfs_client struct
26  */
27 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
28 {
29 	int ret = 0;
30 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
31 
32 	if (clp->rpc_ops->version != 4 || minorversion != 0)
33 		return ret;
34 	idr_preload(GFP_KERNEL);
35 	spin_lock(&nn->nfs_client_lock);
36 	ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
37 	if (ret >= 0)
38 		clp->cl_cb_ident = ret;
39 	spin_unlock(&nn->nfs_client_lock);
40 	idr_preload_end();
41 	return ret < 0 ? ret : 0;
42 }
43 
44 #ifdef CONFIG_NFS_V4_1
45 /**
46  * Per auth flavor data server rpc clients
47  */
48 struct nfs4_ds_server {
49 	struct list_head	list;   /* ds_clp->cl_ds_clients */
50 	struct rpc_clnt		*rpc_clnt;
51 };
52 
53 /**
54  * Common lookup case for DS I/O
55  */
56 static struct nfs4_ds_server *
57 nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
58 {
59 	struct nfs4_ds_server *dss;
60 
61 	rcu_read_lock();
62 	list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
63 		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
64 			continue;
65 		goto out;
66 	}
67 	dss = NULL;
68 out:
69 	rcu_read_unlock();
70 	return dss;
71 }
72 
73 static struct nfs4_ds_server *
74 nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
75 			   struct nfs4_ds_server *new)
76 {
77 	struct nfs4_ds_server *dss;
78 
79 	spin_lock(&ds_clp->cl_lock);
80 	list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
81 		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
82 			continue;
83 		goto out;
84 	}
85 	if (new)
86 		list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
87 	dss = new;
88 out:
89 	spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
90 	return dss;
91 }
92 
93 static struct nfs4_ds_server *
94 nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
95 {
96 	struct nfs4_ds_server *dss;
97 
98 	dss = kmalloc(sizeof(*dss), GFP_NOFS);
99 	if (dss == NULL)
100 		return ERR_PTR(-ENOMEM);
101 
102 	dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
103 	if (IS_ERR(dss->rpc_clnt)) {
104 		int err = PTR_ERR(dss->rpc_clnt);
105 		kfree (dss);
106 		return ERR_PTR(err);
107 	}
108 	INIT_LIST_HEAD(&dss->list);
109 
110 	return dss;
111 }
112 
113 static void
114 nfs4_free_ds_server(struct nfs4_ds_server *dss)
115 {
116 	rpc_release_client(dss->rpc_clnt);
117 	kfree(dss);
118 }
119 
120 /**
121 * Find or create a DS rpc client with th MDS server rpc client auth flavor
122 * in the nfs_client cl_ds_clients list.
123 */
124 struct rpc_clnt *
125 nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
126 {
127 	struct nfs4_ds_server *dss, *new;
128 	rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
129 
130 	dss = nfs4_find_ds_client(ds_clp, flavor);
131 	if (dss != NULL)
132 		goto out;
133 	new = nfs4_alloc_ds_server(ds_clp, flavor);
134 	if (IS_ERR(new))
135 		return ERR_CAST(new);
136 	dss = nfs4_add_ds_client(ds_clp, flavor, new);
137 	if (dss != new)
138 		nfs4_free_ds_server(new);
139 out:
140 	return dss->rpc_clnt;
141 }
142 EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
143 
144 static void
145 nfs4_shutdown_ds_clients(struct nfs_client *clp)
146 {
147 	struct nfs4_ds_server *dss;
148 	LIST_HEAD(shutdown_list);
149 
150 	while (!list_empty(&clp->cl_ds_clients)) {
151 		dss = list_entry(clp->cl_ds_clients.next,
152 					struct nfs4_ds_server, list);
153 		list_del(&dss->list);
154 		rpc_shutdown_client(dss->rpc_clnt);
155 		kfree (dss);
156 	}
157 }
158 
159 void nfs41_shutdown_client(struct nfs_client *clp)
160 {
161 	if (nfs4_has_session(clp)) {
162 		nfs4_shutdown_ds_clients(clp);
163 		nfs4_destroy_session(clp->cl_session);
164 		nfs4_destroy_clientid(clp);
165 	}
166 
167 }
168 #endif	/* CONFIG_NFS_V4_1 */
169 
170 void nfs40_shutdown_client(struct nfs_client *clp)
171 {
172 	if (clp->cl_slot_tbl) {
173 		nfs4_shutdown_slot_table(clp->cl_slot_tbl);
174 		kfree(clp->cl_slot_tbl);
175 	}
176 }
177 
178 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
179 {
180 	int err;
181 	struct nfs_client *clp = nfs_alloc_client(cl_init);
182 	if (IS_ERR(clp))
183 		return clp;
184 
185 	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
186 	if (err)
187 		goto error;
188 
189 	if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
190 		err = -EINVAL;
191 		goto error;
192 	}
193 
194 	spin_lock_init(&clp->cl_lock);
195 	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
196 	INIT_LIST_HEAD(&clp->cl_ds_clients);
197 	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
198 	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
199 	clp->cl_minorversion = cl_init->minorversion;
200 	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
201 	clp->cl_mig_gen = 1;
202 #if IS_ENABLED(CONFIG_NFS_V4_1)
203 	init_waitqueue_head(&clp->cl_lock_waitq);
204 #endif
205 	return clp;
206 
207 error:
208 	nfs_free_client(clp);
209 	return ERR_PTR(err);
210 }
211 
212 /*
213  * Destroy the NFS4 callback service
214  */
215 static void nfs4_destroy_callback(struct nfs_client *clp)
216 {
217 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
218 		nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
219 }
220 
221 static void nfs4_shutdown_client(struct nfs_client *clp)
222 {
223 	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
224 		nfs4_kill_renewd(clp);
225 	clp->cl_mvops->shutdown_client(clp);
226 	nfs4_destroy_callback(clp);
227 	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
228 		nfs_idmap_delete(clp);
229 
230 	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
231 	kfree(clp->cl_serverowner);
232 	kfree(clp->cl_serverscope);
233 	kfree(clp->cl_implid);
234 	kfree(clp->cl_owner_id);
235 }
236 
237 void nfs4_free_client(struct nfs_client *clp)
238 {
239 	nfs4_shutdown_client(clp);
240 	nfs_free_client(clp);
241 }
242 
243 /*
244  * Initialize the NFS4 callback service
245  */
246 static int nfs4_init_callback(struct nfs_client *clp)
247 {
248 	struct rpc_xprt *xprt;
249 	int error;
250 
251 	xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
252 
253 	if (nfs4_has_session(clp)) {
254 		error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
255 		if (error < 0)
256 			return error;
257 	}
258 
259 	error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
260 	if (error < 0) {
261 		dprintk("%s: failed to start callback. Error = %d\n",
262 			__func__, error);
263 		return error;
264 	}
265 	__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
266 
267 	return 0;
268 }
269 
270 /**
271  * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
272  * @clp - nfs_client to initialize
273  *
274  * Returns zero on success, or a negative errno if some error occurred.
275  */
276 int nfs40_init_client(struct nfs_client *clp)
277 {
278 	struct nfs4_slot_table *tbl;
279 	int ret;
280 
281 	tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
282 	if (tbl == NULL)
283 		return -ENOMEM;
284 
285 	ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
286 					"NFSv4.0 transport Slot table");
287 	if (ret) {
288 		kfree(tbl);
289 		return ret;
290 	}
291 
292 	clp->cl_slot_tbl = tbl;
293 	return 0;
294 }
295 
296 #if defined(CONFIG_NFS_V4_1)
297 
298 /**
299  * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
300  * @clp - nfs_client to initialize
301  *
302  * Returns zero on success, or a negative errno if some error occurred.
303  */
304 int nfs41_init_client(struct nfs_client *clp)
305 {
306 	struct nfs4_session *session = NULL;
307 
308 	/*
309 	 * Create the session and mark it expired.
310 	 * When a SEQUENCE operation encounters the expired session
311 	 * it will do session recovery to initialize it.
312 	 */
313 	session = nfs4_alloc_session(clp);
314 	if (!session)
315 		return -ENOMEM;
316 
317 	clp->cl_session = session;
318 
319 	/*
320 	 * The create session reply races with the server back
321 	 * channel probe. Mark the client NFS_CS_SESSION_INITING
322 	 * so that the client back channel can find the
323 	 * nfs_client struct
324 	 */
325 	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
326 	return 0;
327 }
328 
329 #endif	/* CONFIG_NFS_V4_1 */
330 
331 /*
332  * Initialize the minor version specific parts of an NFS4 client record
333  */
334 static int nfs4_init_client_minor_version(struct nfs_client *clp)
335 {
336 	int ret;
337 
338 	ret = clp->cl_mvops->init_client(clp);
339 	if (ret)
340 		return ret;
341 	return nfs4_init_callback(clp);
342 }
343 
344 /**
345  * nfs4_init_client - Initialise an NFS4 client record
346  *
347  * @clp: nfs_client to initialise
348  * @timeparms: timeout parameters for underlying RPC transport
349  * @ip_addr: callback IP address in presentation format
350  * @authflavor: authentication flavor for underlying RPC transport
351  *
352  * Returns pointer to an NFS client, or an ERR_PTR value.
353  */
354 struct nfs_client *nfs4_init_client(struct nfs_client *clp,
355 				    const struct nfs_client_initdata *cl_init)
356 {
357 	char buf[INET6_ADDRSTRLEN + 1];
358 	const char *ip_addr = cl_init->ip_addr;
359 	struct nfs_client *old;
360 	int error;
361 
362 	if (clp->cl_cons_state == NFS_CS_READY) {
363 		/* the client is initialised already */
364 		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
365 		return clp;
366 	}
367 
368 	/* Check NFS protocol revision and initialize RPC op vector */
369 	clp->rpc_ops = &nfs_v4_clientops;
370 
371 	if (clp->cl_minorversion != 0)
372 		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
373 	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
374 	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
375 
376 	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
377 	if (error == -EINVAL)
378 		error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
379 	if (error < 0)
380 		goto error;
381 
382 	/* If no clientaddr= option was specified, find a usable cb address */
383 	if (ip_addr == NULL) {
384 		struct sockaddr_storage cb_addr;
385 		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
386 
387 		error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
388 		if (error < 0)
389 			goto error;
390 		error = rpc_ntop(sap, buf, sizeof(buf));
391 		if (error < 0)
392 			goto error;
393 		ip_addr = (const char *)buf;
394 	}
395 	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
396 
397 	error = nfs_idmap_new(clp);
398 	if (error < 0) {
399 		dprintk("%s: failed to create idmapper. Error = %d\n",
400 			__func__, error);
401 		goto error;
402 	}
403 	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
404 
405 	error = nfs4_init_client_minor_version(clp);
406 	if (error < 0)
407 		goto error;
408 
409 	if (!nfs4_has_session(clp))
410 		nfs_mark_client_ready(clp, NFS_CS_READY);
411 
412 	error = nfs4_discover_server_trunking(clp, &old);
413 	if (error < 0)
414 		goto error;
415 
416 	if (clp != old)
417 		clp->cl_preserve_clid = true;
418 	nfs_put_client(clp);
419 	return old;
420 
421 error:
422 	nfs_mark_client_ready(clp, error);
423 	nfs_put_client(clp);
424 	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
425 	return ERR_PTR(error);
426 }
427 
428 /*
429  * SETCLIENTID just did a callback update with the callback ident in
430  * "drop," but server trunking discovery claims "drop" and "keep" are
431  * actually the same server.  Swap the callback IDs so that "keep"
432  * will continue to use the callback ident the server now knows about,
433  * and so that "keep"'s original callback ident is destroyed when
434  * "drop" is freed.
435  */
436 static void nfs4_swap_callback_idents(struct nfs_client *keep,
437 				      struct nfs_client *drop)
438 {
439 	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
440 	unsigned int save = keep->cl_cb_ident;
441 
442 	if (keep->cl_cb_ident == drop->cl_cb_ident)
443 		return;
444 
445 	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
446 		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
447 
448 	spin_lock(&nn->nfs_client_lock);
449 
450 	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
451 	keep->cl_cb_ident = drop->cl_cb_ident;
452 
453 	idr_replace(&nn->cb_ident_idr, drop, save);
454 	drop->cl_cb_ident = save;
455 
456 	spin_unlock(&nn->nfs_client_lock);
457 }
458 
459 static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
460 		const struct nfs_client *clp2)
461 {
462 	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
463 		return true;
464 	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
465 }
466 
467 static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
468 {
469 	return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
470 }
471 
472 /**
473  * nfs40_walk_client_list - Find server that recognizes a client ID
474  *
475  * @new: nfs_client with client ID to test
476  * @result: OUT: found nfs_client, or new
477  * @cred: credential to use for trunking test
478  *
479  * Returns zero, a negative errno, or a negative NFS4ERR status.
480  * If zero is returned, an nfs_client pointer is planted in "result."
481  *
482  * NB: nfs40_walk_client_list() relies on the new nfs_client being
483  *     the last nfs_client on the list.
484  */
485 int nfs40_walk_client_list(struct nfs_client *new,
486 			   struct nfs_client **result,
487 			   struct rpc_cred *cred)
488 {
489 	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
490 	struct nfs_client *pos, *prev = NULL;
491 	struct nfs4_setclientid_res clid = {
492 		.clientid	= new->cl_clientid,
493 		.confirm	= new->cl_confirm,
494 	};
495 	int status = -NFS4ERR_STALE_CLIENTID;
496 
497 	spin_lock(&nn->nfs_client_lock);
498 	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
499 
500 		if (pos->rpc_ops != new->rpc_ops)
501 			continue;
502 
503 		if (pos->cl_minorversion != new->cl_minorversion)
504 			continue;
505 
506 		/* If "pos" isn't marked ready, we can't trust the
507 		 * remaining fields in "pos" */
508 		if (pos->cl_cons_state > NFS_CS_READY) {
509 			atomic_inc(&pos->cl_count);
510 			spin_unlock(&nn->nfs_client_lock);
511 
512 			nfs_put_client(prev);
513 			prev = pos;
514 
515 			status = nfs_wait_client_init_complete(pos);
516 			if (status < 0)
517 				goto out;
518 			status = -NFS4ERR_STALE_CLIENTID;
519 			spin_lock(&nn->nfs_client_lock);
520 		}
521 		if (pos->cl_cons_state != NFS_CS_READY)
522 			continue;
523 
524 		if (pos->cl_clientid != new->cl_clientid)
525 			continue;
526 
527 		if (!nfs4_match_client_owner_id(pos, new))
528 			continue;
529 		/*
530 		 * We just sent a new SETCLIENTID, which should have
531 		 * caused the server to return a new cl_confirm.  So if
532 		 * cl_confirm is the same, then this is a different
533 		 * server that just returned the same cl_confirm by
534 		 * coincidence:
535 		 */
536 		if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
537 						       &new->cl_confirm))
538 			continue;
539 		/*
540 		 * But if the cl_confirm's are different, then the only
541 		 * way that a SETCLIENTID_CONFIRM to pos can succeed is
542 		 * if new and pos point to the same server:
543 		 */
544 		atomic_inc(&pos->cl_count);
545 		spin_unlock(&nn->nfs_client_lock);
546 
547 		nfs_put_client(prev);
548 		prev = pos;
549 
550 		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
551 		switch (status) {
552 		case -NFS4ERR_STALE_CLIENTID:
553 			break;
554 		case 0:
555 			nfs4_swap_callback_idents(pos, new);
556 			pos->cl_confirm = new->cl_confirm;
557 
558 			prev = NULL;
559 			*result = pos;
560 			dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
561 				__func__, pos, atomic_read(&pos->cl_count));
562 			goto out;
563 		case -ERESTARTSYS:
564 		case -ETIMEDOUT:
565 			/* The callback path may have been inadvertently
566 			 * changed. Schedule recovery!
567 			 */
568 			nfs4_schedule_path_down_recovery(pos);
569 		default:
570 			goto out;
571 		}
572 
573 		spin_lock(&nn->nfs_client_lock);
574 	}
575 	spin_unlock(&nn->nfs_client_lock);
576 
577 	/* No match found. The server lost our clientid */
578 out:
579 	nfs_put_client(prev);
580 	dprintk("NFS: <-- %s status = %d\n", __func__, status);
581 	return status;
582 }
583 
584 #ifdef CONFIG_NFS_V4_1
585 /*
586  * Returns true if the client IDs match
587  */
588 static bool nfs4_match_clientids(u64 a, u64 b)
589 {
590 	if (a != b) {
591 		dprintk("NFS: --> %s client ID %llx does not match %llx\n",
592 			__func__, a, b);
593 		return false;
594 	}
595 	dprintk("NFS: --> %s client ID %llx matches %llx\n",
596 		__func__, a, b);
597 	return true;
598 }
599 
600 /*
601  * Returns true if the server major ids match
602  */
603 static bool
604 nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
605 				struct nfs41_server_owner *o2)
606 {
607 	if (o1->major_id_sz != o2->major_id_sz)
608 		goto out_major_mismatch;
609 	if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0)
610 		goto out_major_mismatch;
611 
612 	dprintk("NFS: --> %s server owner major IDs match\n", __func__);
613 	return true;
614 
615 out_major_mismatch:
616 	dprintk("NFS: --> %s server owner major IDs do not match\n",
617 		__func__);
618 	return false;
619 }
620 
621 /*
622  * Returns true if server minor ids match
623  */
624 static bool
625 nfs4_check_serverowner_minor_id(struct nfs41_server_owner *o1,
626 				struct nfs41_server_owner *o2)
627 {
628 	/* Check eir_server_owner so_minor_id */
629 	if (o1->minor_id != o2->minor_id)
630 		goto out_minor_mismatch;
631 
632 	dprintk("NFS: --> %s server owner minor IDs match\n", __func__);
633 	return true;
634 
635 out_minor_mismatch:
636 	dprintk("NFS: --> %s server owner minor IDs do not match\n", __func__);
637 	return false;
638 }
639 
640 /*
641  * Returns true if the server scopes match
642  */
643 static bool
644 nfs4_check_server_scope(struct nfs41_server_scope *s1,
645 			struct nfs41_server_scope *s2)
646 {
647 	if (s1->server_scope_sz != s2->server_scope_sz)
648 		goto out_scope_mismatch;
649 	if (memcmp(s1->server_scope, s2->server_scope,
650 		   s1->server_scope_sz) != 0)
651 		goto out_scope_mismatch;
652 
653 	dprintk("NFS: --> %s server scopes match\n", __func__);
654 	return true;
655 
656 out_scope_mismatch:
657 	dprintk("NFS: --> %s server scopes do not match\n",
658 		__func__);
659 	return false;
660 }
661 
662 /**
663  * nfs4_detect_session_trunking - Checks for session trunking.
664  *
665  * Called after a successful EXCHANGE_ID on a multi-addr connection.
666  * Upon success, add the transport.
667  *
668  * @clp:    original mount nfs_client
669  * @res:    result structure from an exchange_id using the original mount
670  *          nfs_client with a new multi_addr transport
671  *
672  * Returns zero on success, otherwise -EINVAL
673  *
674  * Note: since the exchange_id for the new multi_addr transport uses the
675  * same nfs_client from the original mount, the cl_owner_id is reused,
676  * so eir_clientowner is the same.
677  */
678 int nfs4_detect_session_trunking(struct nfs_client *clp,
679 				 struct nfs41_exchange_id_res *res,
680 				 struct rpc_xprt *xprt)
681 {
682 	/* Check eir_clientid */
683 	if (!nfs4_match_clientids(clp->cl_clientid, res->clientid))
684 		goto out_err;
685 
686 	/* Check eir_server_owner so_major_id */
687 	if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
688 					     res->server_owner))
689 		goto out_err;
690 
691 	/* Check eir_server_owner so_minor_id */
692 	if (!nfs4_check_serverowner_minor_id(clp->cl_serverowner,
693 					     res->server_owner))
694 		goto out_err;
695 
696 	/* Check eir_server_scope */
697 	if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
698 		goto out_err;
699 
700 	/* Session trunking passed, add the xprt */
701 	rpc_clnt_xprt_switch_add_xprt(clp->cl_rpcclient, xprt);
702 
703 	pr_info("NFS:  %s: Session trunking succeeded for %s\n",
704 		clp->cl_hostname,
705 		xprt->address_strings[RPC_DISPLAY_ADDR]);
706 
707 	return 0;
708 out_err:
709 	pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
710 		xprt->address_strings[RPC_DISPLAY_ADDR]);
711 
712 	return -EINVAL;
713 }
714 
715 /**
716  * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
717  *
718  * @new: nfs_client with client ID to test
719  * @result: OUT: found nfs_client, or new
720  * @cred: credential to use for trunking test
721  *
722  * Returns zero, a negative errno, or a negative NFS4ERR status.
723  * If zero is returned, an nfs_client pointer is planted in "result."
724  *
725  * NB: nfs41_walk_client_list() relies on the new nfs_client being
726  *     the last nfs_client on the list.
727  */
728 int nfs41_walk_client_list(struct nfs_client *new,
729 			   struct nfs_client **result,
730 			   struct rpc_cred *cred)
731 {
732 	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
733 	struct nfs_client *pos, *prev = NULL;
734 	int status = -NFS4ERR_STALE_CLIENTID;
735 
736 	spin_lock(&nn->nfs_client_lock);
737 	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
738 
739 		if (pos == new)
740 			goto found;
741 
742 		if (pos->rpc_ops != new->rpc_ops)
743 			continue;
744 
745 		if (pos->cl_minorversion != new->cl_minorversion)
746 			continue;
747 
748 		/* If "pos" isn't marked ready, we can't trust the
749 		 * remaining fields in "pos", especially the client
750 		 * ID and serverowner fields.  Wait for CREATE_SESSION
751 		 * to finish. */
752 		if (pos->cl_cons_state > NFS_CS_READY) {
753 			atomic_inc(&pos->cl_count);
754 			spin_unlock(&nn->nfs_client_lock);
755 
756 			nfs_put_client(prev);
757 			prev = pos;
758 
759 			status = nfs_wait_client_init_complete(pos);
760 			spin_lock(&nn->nfs_client_lock);
761 			if (status < 0)
762 				break;
763 			status = -NFS4ERR_STALE_CLIENTID;
764 		}
765 		if (pos->cl_cons_state != NFS_CS_READY)
766 			continue;
767 
768 		if (!nfs4_match_clientids(pos->cl_clientid, new->cl_clientid))
769 			continue;
770 
771 		/*
772 		 * Note that session trunking is just a special subcase of
773 		 * client id trunking. In either case, we want to fall back
774 		 * to using the existing nfs_client.
775 		 */
776 		if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
777 						     new->cl_serverowner))
778 			continue;
779 
780 		/* Unlike NFSv4.0, we know that NFSv4.1 always uses the
781 		 * uniform string, however someone might switch the
782 		 * uniquifier string on us.
783 		 */
784 		if (!nfs4_match_client_owner_id(pos, new))
785 			continue;
786 found:
787 		atomic_inc(&pos->cl_count);
788 		*result = pos;
789 		status = 0;
790 		dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
791 			__func__, pos, atomic_read(&pos->cl_count));
792 		break;
793 	}
794 
795 	spin_unlock(&nn->nfs_client_lock);
796 	dprintk("NFS: <-- %s status = %d\n", __func__, status);
797 	nfs_put_client(prev);
798 	return status;
799 }
800 #endif	/* CONFIG_NFS_V4_1 */
801 
802 static void nfs4_destroy_server(struct nfs_server *server)
803 {
804 	nfs_server_return_all_delegations(server);
805 	unset_pnfs_layoutdriver(server);
806 	nfs4_purge_state_owners(server);
807 }
808 
809 /*
810  * NFSv4.0 callback thread helper
811  *
812  * Find a client by callback identifier
813  */
814 struct nfs_client *
815 nfs4_find_client_ident(struct net *net, int cb_ident)
816 {
817 	struct nfs_client *clp;
818 	struct nfs_net *nn = net_generic(net, nfs_net_id);
819 
820 	spin_lock(&nn->nfs_client_lock);
821 	clp = idr_find(&nn->cb_ident_idr, cb_ident);
822 	if (clp)
823 		atomic_inc(&clp->cl_count);
824 	spin_unlock(&nn->nfs_client_lock);
825 	return clp;
826 }
827 
828 #if defined(CONFIG_NFS_V4_1)
829 /* Common match routine for v4.0 and v4.1 callback services */
830 static bool nfs4_cb_match_client(const struct sockaddr *addr,
831 		struct nfs_client *clp, u32 minorversion)
832 {
833 	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
834 
835 	/* Don't match clients that failed to initialise */
836 	if (!(clp->cl_cons_state == NFS_CS_READY ||
837 	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
838 		return false;
839 
840 	smp_rmb();
841 
842 	/* Match the version and minorversion */
843 	if (clp->rpc_ops->version != 4 ||
844 	    clp->cl_minorversion != minorversion)
845 		return false;
846 
847 	/* Match only the IP address, not the port number */
848 	return rpc_cmp_addr(addr, clap);
849 }
850 
851 /*
852  * NFSv4.1 callback thread helper
853  * For CB_COMPOUND calls, find a client by IP address, protocol version,
854  * minorversion, and sessionID
855  *
856  * Returns NULL if no such client
857  */
858 struct nfs_client *
859 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
860 			   struct nfs4_sessionid *sid, u32 minorversion)
861 {
862 	struct nfs_client *clp;
863 	struct nfs_net *nn = net_generic(net, nfs_net_id);
864 
865 	spin_lock(&nn->nfs_client_lock);
866 	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
867 		if (nfs4_cb_match_client(addr, clp, minorversion) == false)
868 			continue;
869 
870 		if (!nfs4_has_session(clp))
871 			continue;
872 
873 		/* Match sessionid*/
874 		if (memcmp(clp->cl_session->sess_id.data,
875 		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
876 			continue;
877 
878 		atomic_inc(&clp->cl_count);
879 		spin_unlock(&nn->nfs_client_lock);
880 		return clp;
881 	}
882 	spin_unlock(&nn->nfs_client_lock);
883 	return NULL;
884 }
885 
886 #else /* CONFIG_NFS_V4_1 */
887 
888 struct nfs_client *
889 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
890 			   struct nfs4_sessionid *sid, u32 minorversion)
891 {
892 	return NULL;
893 }
894 #endif /* CONFIG_NFS_V4_1 */
895 
896 /*
897  * Set up an NFS4 client
898  */
899 static int nfs4_set_client(struct nfs_server *server,
900 		const char *hostname,
901 		const struct sockaddr *addr,
902 		const size_t addrlen,
903 		const char *ip_addr,
904 		int proto, const struct rpc_timeout *timeparms,
905 		u32 minorversion, struct net *net)
906 {
907 	struct nfs_client_initdata cl_init = {
908 		.hostname = hostname,
909 		.addr = addr,
910 		.addrlen = addrlen,
911 		.ip_addr = ip_addr,
912 		.nfs_mod = &nfs_v4,
913 		.proto = proto,
914 		.minorversion = minorversion,
915 		.net = net,
916 		.timeparms = timeparms,
917 	};
918 	struct nfs_client *clp;
919 	int error;
920 
921 	dprintk("--> nfs4_set_client()\n");
922 
923 	if (server->flags & NFS_MOUNT_NORESVPORT)
924 		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
925 	if (server->options & NFS_OPTION_MIGRATION)
926 		set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
927 
928 	/* Allocate or find a client reference we can use */
929 	clp = nfs_get_client(&cl_init);
930 	if (IS_ERR(clp)) {
931 		error = PTR_ERR(clp);
932 		goto error;
933 	}
934 
935 	if (server->nfs_client == clp) {
936 		error = -ELOOP;
937 		goto error;
938 	}
939 
940 	/*
941 	 * Query for the lease time on clientid setup or renewal
942 	 *
943 	 * Note that this will be set on nfs_clients that were created
944 	 * only for the DS role and did not set this bit, but now will
945 	 * serve a dual role.
946 	 */
947 	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
948 
949 	server->nfs_client = clp;
950 	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
951 	return 0;
952 error:
953 	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
954 	return error;
955 }
956 
957 /*
958  * Set up a pNFS Data Server client.
959  *
960  * Return any existing nfs_client that matches server address,port,version
961  * and minorversion.
962  *
963  * For a new nfs_client, use a soft mount (default), a low retrans and a
964  * low timeout interval so that if a connection is lost, we retry through
965  * the MDS.
966  */
967 struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
968 		const struct sockaddr *ds_addr, int ds_addrlen,
969 		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
970 		u32 minor_version)
971 {
972 	struct rpc_timeout ds_timeout;
973 	struct nfs_client *mds_clp = mds_srv->nfs_client;
974 	struct nfs_client_initdata cl_init = {
975 		.addr = ds_addr,
976 		.addrlen = ds_addrlen,
977 		.nodename = mds_clp->cl_rpcclient->cl_nodename,
978 		.ip_addr = mds_clp->cl_ipaddr,
979 		.nfs_mod = &nfs_v4,
980 		.proto = ds_proto,
981 		.minorversion = minor_version,
982 		.net = mds_clp->cl_net,
983 		.timeparms = &ds_timeout,
984 	};
985 	struct nfs_client *clp;
986 	char buf[INET6_ADDRSTRLEN + 1];
987 
988 	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
989 		return ERR_PTR(-EINVAL);
990 	cl_init.hostname = buf;
991 
992 	if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
993 		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
994 
995 	/*
996 	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
997 	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
998 	 * (section 13.1 RFC 5661).
999 	 */
1000 	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
1001 	clp = nfs_get_client(&cl_init);
1002 
1003 	dprintk("<-- %s %p\n", __func__, clp);
1004 	return clp;
1005 }
1006 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
1007 
1008 /*
1009  * Session has been established, and the client marked ready.
1010  * Set the mount rsize and wsize with negotiated fore channel
1011  * attributes which will be bound checked in nfs_server_set_fsinfo.
1012  */
1013 static void nfs4_session_set_rwsize(struct nfs_server *server)
1014 {
1015 #ifdef CONFIG_NFS_V4_1
1016 	struct nfs4_session *sess;
1017 	u32 server_resp_sz;
1018 	u32 server_rqst_sz;
1019 
1020 	if (!nfs4_has_session(server->nfs_client))
1021 		return;
1022 	sess = server->nfs_client->cl_session;
1023 	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
1024 	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
1025 
1026 	if (!server->rsize || server->rsize > server_resp_sz)
1027 		server->rsize = server_resp_sz;
1028 	if (!server->wsize || server->wsize > server_rqst_sz)
1029 		server->wsize = server_rqst_sz;
1030 #endif /* CONFIG_NFS_V4_1 */
1031 }
1032 
1033 static int nfs4_server_common_setup(struct nfs_server *server,
1034 		struct nfs_fh *mntfh, bool auth_probe)
1035 {
1036 	struct nfs_fattr *fattr;
1037 	int error;
1038 
1039 	/* data servers support only a subset of NFSv4.1 */
1040 	if (is_ds_only_client(server->nfs_client))
1041 		return -EPROTONOSUPPORT;
1042 
1043 	fattr = nfs_alloc_fattr();
1044 	if (fattr == NULL)
1045 		return -ENOMEM;
1046 
1047 	/* We must ensure the session is initialised first */
1048 	error = nfs4_init_session(server->nfs_client);
1049 	if (error < 0)
1050 		goto out;
1051 
1052 	/* Set the basic capabilities */
1053 	server->caps |= server->nfs_client->cl_mvops->init_caps;
1054 	if (server->flags & NFS_MOUNT_NORDIRPLUS)
1055 			server->caps &= ~NFS_CAP_READDIRPLUS;
1056 	/*
1057 	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
1058 	 * authentication.
1059 	 */
1060 	if (nfs4_disable_idmapping &&
1061 			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
1062 		server->caps |= NFS_CAP_UIDGID_NOMAP;
1063 
1064 
1065 	/* Probe the root fh to retrieve its FSID and filehandle */
1066 	error = nfs4_get_rootfh(server, mntfh, auth_probe);
1067 	if (error < 0)
1068 		goto out;
1069 
1070 	dprintk("Server FSID: %llx:%llx\n",
1071 			(unsigned long long) server->fsid.major,
1072 			(unsigned long long) server->fsid.minor);
1073 	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1074 
1075 	nfs4_session_set_rwsize(server);
1076 
1077 	error = nfs_probe_fsinfo(server, mntfh, fattr);
1078 	if (error < 0)
1079 		goto out;
1080 
1081 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1082 		server->namelen = NFS4_MAXNAMLEN;
1083 
1084 	nfs_server_insert_lists(server);
1085 	server->mount_time = jiffies;
1086 	server->destroy = nfs4_destroy_server;
1087 out:
1088 	nfs_free_fattr(fattr);
1089 	return error;
1090 }
1091 
1092 /*
1093  * Create a version 4 volume record
1094  */
1095 static int nfs4_init_server(struct nfs_server *server,
1096 		struct nfs_parsed_mount_data *data)
1097 {
1098 	struct rpc_timeout timeparms;
1099 	int error;
1100 
1101 	dprintk("--> nfs4_init_server()\n");
1102 
1103 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1104 			data->timeo, data->retrans);
1105 
1106 	/* Initialise the client representation from the mount data */
1107 	server->flags = data->flags;
1108 	server->options = data->options;
1109 	server->auth_info = data->auth_info;
1110 
1111 	/* Use the first specified auth flavor. If this flavor isn't
1112 	 * allowed by the server, use the SECINFO path to try the
1113 	 * other specified flavors */
1114 	if (data->auth_info.flavor_len >= 1)
1115 		data->selected_flavor = data->auth_info.flavors[0];
1116 	else
1117 		data->selected_flavor = RPC_AUTH_UNIX;
1118 
1119 	/* Get a client record */
1120 	error = nfs4_set_client(server,
1121 			data->nfs_server.hostname,
1122 			(const struct sockaddr *)&data->nfs_server.address,
1123 			data->nfs_server.addrlen,
1124 			data->client_address,
1125 			data->nfs_server.protocol,
1126 			&timeparms,
1127 			data->minorversion,
1128 			data->net);
1129 	if (error < 0)
1130 		goto error;
1131 
1132 	if (data->rsize)
1133 		server->rsize = nfs_block_size(data->rsize, NULL);
1134 	if (data->wsize)
1135 		server->wsize = nfs_block_size(data->wsize, NULL);
1136 
1137 	server->acregmin = data->acregmin * HZ;
1138 	server->acregmax = data->acregmax * HZ;
1139 	server->acdirmin = data->acdirmin * HZ;
1140 	server->acdirmax = data->acdirmax * HZ;
1141 
1142 	server->port = data->nfs_server.port;
1143 
1144 	error = nfs_init_server_rpcclient(server, &timeparms,
1145 					  data->selected_flavor);
1146 
1147 error:
1148 	/* Done */
1149 	dprintk("<-- nfs4_init_server() = %d\n", error);
1150 	return error;
1151 }
1152 
1153 /*
1154  * Create a version 4 volume record
1155  * - keyed on server and FSID
1156  */
1157 /*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1158 				      struct nfs_fh *mntfh)*/
1159 struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1160 				      struct nfs_subversion *nfs_mod)
1161 {
1162 	struct nfs_server *server;
1163 	bool auth_probe;
1164 	int error;
1165 
1166 	dprintk("--> nfs4_create_server()\n");
1167 
1168 	server = nfs_alloc_server();
1169 	if (!server)
1170 		return ERR_PTR(-ENOMEM);
1171 
1172 	auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1173 
1174 	/* set up the general RPC client */
1175 	error = nfs4_init_server(server, mount_info->parsed);
1176 	if (error < 0)
1177 		goto error;
1178 
1179 	error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1180 	if (error < 0)
1181 		goto error;
1182 
1183 	dprintk("<-- nfs4_create_server() = %p\n", server);
1184 	return server;
1185 
1186 error:
1187 	nfs_free_server(server);
1188 	dprintk("<-- nfs4_create_server() = error %d\n", error);
1189 	return ERR_PTR(error);
1190 }
1191 
1192 /*
1193  * Create an NFS4 referral server record
1194  */
1195 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1196 					       struct nfs_fh *mntfh)
1197 {
1198 	struct nfs_client *parent_client;
1199 	struct nfs_server *server, *parent_server;
1200 	bool auth_probe;
1201 	int error;
1202 
1203 	dprintk("--> nfs4_create_referral_server()\n");
1204 
1205 	server = nfs_alloc_server();
1206 	if (!server)
1207 		return ERR_PTR(-ENOMEM);
1208 
1209 	parent_server = NFS_SB(data->sb);
1210 	parent_client = parent_server->nfs_client;
1211 
1212 	/* Initialise the client representation from the parent server */
1213 	nfs_server_copy_userdata(server, parent_server);
1214 
1215 	/* Get a client representation.
1216 	 * Note: NFSv4 always uses TCP, */
1217 	error = nfs4_set_client(server, data->hostname,
1218 				data->addr,
1219 				data->addrlen,
1220 				parent_client->cl_ipaddr,
1221 				rpc_protocol(parent_server->client),
1222 				parent_server->client->cl_timeout,
1223 				parent_client->cl_mvops->minor_version,
1224 				parent_client->cl_net);
1225 	if (error < 0)
1226 		goto error;
1227 
1228 	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1229 	if (error < 0)
1230 		goto error;
1231 
1232 	auth_probe = parent_server->auth_info.flavor_len < 1;
1233 
1234 	error = nfs4_server_common_setup(server, mntfh, auth_probe);
1235 	if (error < 0)
1236 		goto error;
1237 
1238 	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1239 	return server;
1240 
1241 error:
1242 	nfs_free_server(server);
1243 	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1244 	return ERR_PTR(error);
1245 }
1246 
1247 /*
1248  * Grab the destination's particulars, including lease expiry time.
1249  *
1250  * Returns zero if probe succeeded and retrieved FSID matches the FSID
1251  * we have cached.
1252  */
1253 static int nfs_probe_destination(struct nfs_server *server)
1254 {
1255 	struct inode *inode = d_inode(server->super->s_root);
1256 	struct nfs_fattr *fattr;
1257 	int error;
1258 
1259 	fattr = nfs_alloc_fattr();
1260 	if (fattr == NULL)
1261 		return -ENOMEM;
1262 
1263 	/* Sanity: the probe won't work if the destination server
1264 	 * does not recognize the migrated FH. */
1265 	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1266 
1267 	nfs_free_fattr(fattr);
1268 	return error;
1269 }
1270 
1271 /**
1272  * nfs4_update_server - Move an nfs_server to a different nfs_client
1273  *
1274  * @server: represents FSID to be moved
1275  * @hostname: new end-point's hostname
1276  * @sap: new end-point's socket address
1277  * @salen: size of "sap"
1278  * @net: net namespace
1279  *
1280  * The nfs_server must be quiescent before this function is invoked.
1281  * Either its session is drained (NFSv4.1+), or its transport is
1282  * plugged and drained (NFSv4.0).
1283  *
1284  * Returns zero on success, or a negative errno value.
1285  */
1286 int nfs4_update_server(struct nfs_server *server, const char *hostname,
1287 		       struct sockaddr *sap, size_t salen, struct net *net)
1288 {
1289 	struct nfs_client *clp = server->nfs_client;
1290 	struct rpc_clnt *clnt = server->client;
1291 	struct xprt_create xargs = {
1292 		.ident		= clp->cl_proto,
1293 		.net		= net,
1294 		.dstaddr	= sap,
1295 		.addrlen	= salen,
1296 		.servername	= hostname,
1297 	};
1298 	char buf[INET6_ADDRSTRLEN + 1];
1299 	struct sockaddr_storage address;
1300 	struct sockaddr *localaddr = (struct sockaddr *)&address;
1301 	int error;
1302 
1303 	dprintk("--> %s: move FSID %llx:%llx to \"%s\")\n", __func__,
1304 			(unsigned long long)server->fsid.major,
1305 			(unsigned long long)server->fsid.minor,
1306 			hostname);
1307 
1308 	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1309 	if (error != 0) {
1310 		dprintk("<-- %s(): rpc_switch_client_transport returned %d\n",
1311 			__func__, error);
1312 		goto out;
1313 	}
1314 
1315 	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1316 	if (error != 0) {
1317 		dprintk("<-- %s(): rpc_localaddr returned %d\n",
1318 			__func__, error);
1319 		goto out;
1320 	}
1321 
1322 	error = -EAFNOSUPPORT;
1323 	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0) {
1324 		dprintk("<-- %s(): rpc_ntop returned %d\n",
1325 			__func__, error);
1326 		goto out;
1327 	}
1328 
1329 	nfs_server_remove_lists(server);
1330 	error = nfs4_set_client(server, hostname, sap, salen, buf,
1331 				clp->cl_proto, clnt->cl_timeout,
1332 				clp->cl_minorversion, net);
1333 	nfs_put_client(clp);
1334 	if (error != 0) {
1335 		nfs_server_insert_lists(server);
1336 		dprintk("<-- %s(): nfs4_set_client returned %d\n",
1337 			__func__, error);
1338 		goto out;
1339 	}
1340 
1341 	if (server->nfs_client->cl_hostname == NULL)
1342 		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1343 	nfs_server_insert_lists(server);
1344 
1345 	error = nfs_probe_destination(server);
1346 	if (error < 0)
1347 		goto out;
1348 
1349 	dprintk("<-- %s() succeeded\n", __func__);
1350 
1351 out:
1352 	return error;
1353 }
1354