xref: /linux/fs/nfs/nfs4client.c (revision 2d07c6c2098805054f84ce642587093bb8feaf8c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  */
6 #include <linux/module.h>
7 #include <linux/nfs_fs.h>
8 #include <linux/nfs_mount.h>
9 #include <linux/sunrpc/addr.h>
10 #include <linux/sunrpc/auth.h>
11 #include <linux/sunrpc/xprt.h>
12 #include <linux/sunrpc/bc_xprt.h>
13 #include <linux/sunrpc/rpc_pipe_fs.h>
14 #include "internal.h"
15 #include "callback.h"
16 #include "delegation.h"
17 #include "nfs4session.h"
18 #include "nfs4idmap.h"
19 #include "pnfs.h"
20 #include "netns.h"
21 #include "sysfs.h"
22 
23 #define NFSDBG_FACILITY		NFSDBG_CLIENT
24 
25 /*
26  * Get a unique NFSv4.0 callback identifier which will be used
27  * by the V4.0 callback service to lookup the nfs_client struct
28  */
nfs_get_cb_ident_idr(struct nfs_client * clp,int minorversion)29 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
30 {
31 	int ret = 0;
32 	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
33 
34 	if (clp->rpc_ops->version != 4 || minorversion != 0)
35 		return ret;
36 	idr_preload(GFP_KERNEL);
37 	spin_lock(&nn->nfs_client_lock);
38 	ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
39 	if (ret >= 0)
40 		clp->cl_cb_ident = ret;
41 	spin_unlock(&nn->nfs_client_lock);
42 	idr_preload_end();
43 	return ret < 0 ? ret : 0;
44 }
45 
46 #ifdef CONFIG_NFS_V4_1
47 /*
48  * Per auth flavor data server rpc clients
49  */
50 struct nfs4_ds_server {
51 	struct list_head	list;   /* ds_clp->cl_ds_clients */
52 	struct rpc_clnt		*rpc_clnt;
53 };
54 
55 /**
56  * nfs4_find_ds_client - Common lookup case for DS I/O
57  * @ds_clp: pointer to the DS's nfs_client
58  * @flavor: rpc auth flavour to match
59  */
60 static struct nfs4_ds_server *
nfs4_find_ds_client(struct nfs_client * ds_clp,rpc_authflavor_t flavor)61 nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
62 {
63 	struct nfs4_ds_server *dss;
64 
65 	rcu_read_lock();
66 	list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
67 		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
68 			continue;
69 		goto out;
70 	}
71 	dss = NULL;
72 out:
73 	rcu_read_unlock();
74 	return dss;
75 }
76 
77 static struct nfs4_ds_server *
nfs4_add_ds_client(struct nfs_client * ds_clp,rpc_authflavor_t flavor,struct nfs4_ds_server * new)78 nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
79 			   struct nfs4_ds_server *new)
80 {
81 	struct nfs4_ds_server *dss;
82 
83 	spin_lock(&ds_clp->cl_lock);
84 	list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
85 		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
86 			continue;
87 		goto out;
88 	}
89 	if (new)
90 		list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
91 	dss = new;
92 out:
93 	spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
94 	return dss;
95 }
96 
97 static struct nfs4_ds_server *
nfs4_alloc_ds_server(struct nfs_client * ds_clp,rpc_authflavor_t flavor)98 nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
99 {
100 	struct nfs4_ds_server *dss;
101 
102 	dss = kmalloc(sizeof(*dss), GFP_NOFS);
103 	if (dss == NULL)
104 		return ERR_PTR(-ENOMEM);
105 
106 	dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
107 	if (IS_ERR(dss->rpc_clnt)) {
108 		int err = PTR_ERR(dss->rpc_clnt);
109 		kfree (dss);
110 		return ERR_PTR(err);
111 	}
112 	INIT_LIST_HEAD(&dss->list);
113 
114 	return dss;
115 }
116 
117 static void
nfs4_free_ds_server(struct nfs4_ds_server * dss)118 nfs4_free_ds_server(struct nfs4_ds_server *dss)
119 {
120 	rpc_release_client(dss->rpc_clnt);
121 	kfree(dss);
122 }
123 
124 /**
125  * nfs4_find_or_create_ds_client - Find or create a DS rpc client
126  * @ds_clp: pointer to the DS's nfs_client
127  * @inode: pointer to the inode
128  *
129  * Find or create a DS rpc client with th MDS server rpc client auth flavor
130  * in the nfs_client cl_ds_clients list.
131  */
132 struct rpc_clnt *
nfs4_find_or_create_ds_client(struct nfs_client * ds_clp,struct inode * inode)133 nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
134 {
135 	struct nfs4_ds_server *dss, *new;
136 	rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
137 
138 	dss = nfs4_find_ds_client(ds_clp, flavor);
139 	if (dss != NULL)
140 		goto out;
141 	new = nfs4_alloc_ds_server(ds_clp, flavor);
142 	if (IS_ERR(new))
143 		return ERR_CAST(new);
144 	dss = nfs4_add_ds_client(ds_clp, flavor, new);
145 	if (dss != new)
146 		nfs4_free_ds_server(new);
147 out:
148 	return dss->rpc_clnt;
149 }
150 EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
151 
152 static void
nfs4_shutdown_ds_clients(struct nfs_client * clp)153 nfs4_shutdown_ds_clients(struct nfs_client *clp)
154 {
155 	struct nfs4_ds_server *dss;
156 
157 	while (!list_empty(&clp->cl_ds_clients)) {
158 		dss = list_entry(clp->cl_ds_clients.next,
159 					struct nfs4_ds_server, list);
160 		list_del(&dss->list);
161 		rpc_shutdown_client(dss->rpc_clnt);
162 		kfree (dss);
163 	}
164 }
165 
166 static void
nfs4_cleanup_callback(struct nfs_client * clp)167 nfs4_cleanup_callback(struct nfs_client *clp)
168 {
169 	struct nfs4_copy_state *cp_state;
170 
171 	while (!list_empty(&clp->pending_cb_stateids)) {
172 		cp_state = list_entry(clp->pending_cb_stateids.next,
173 					struct nfs4_copy_state, copies);
174 		list_del(&cp_state->copies);
175 		kfree(cp_state);
176 	}
177 }
178 
nfs41_shutdown_client(struct nfs_client * clp)179 void nfs41_shutdown_client(struct nfs_client *clp)
180 {
181 	if (nfs4_has_session(clp)) {
182 		nfs4_cleanup_callback(clp);
183 		nfs4_shutdown_ds_clients(clp);
184 		nfs4_destroy_session(clp->cl_session);
185 		nfs4_destroy_clientid(clp);
186 	}
187 
188 }
189 #endif	/* CONFIG_NFS_V4_1 */
190 
nfs40_shutdown_client(struct nfs_client * clp)191 void nfs40_shutdown_client(struct nfs_client *clp)
192 {
193 	if (clp->cl_slot_tbl) {
194 		nfs4_shutdown_slot_table(clp->cl_slot_tbl);
195 		kfree(clp->cl_slot_tbl);
196 	}
197 }
198 
nfs4_alloc_client(const struct nfs_client_initdata * cl_init)199 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
200 {
201 	char buf[INET6_ADDRSTRLEN + 1];
202 	const char *ip_addr = cl_init->ip_addr;
203 	struct nfs_client *clp = nfs_alloc_client(cl_init);
204 	int err;
205 
206 	if (IS_ERR(clp))
207 		return clp;
208 
209 	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
210 	if (err)
211 		goto error;
212 
213 	if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
214 		err = -EINVAL;
215 		goto error;
216 	}
217 
218 	spin_lock_init(&clp->cl_lock);
219 	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
220 	INIT_LIST_HEAD(&clp->cl_ds_clients);
221 	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
222 	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
223 	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
224 	clp->cl_mig_gen = 1;
225 	clp->cl_last_renewal = jiffies;
226 #if IS_ENABLED(CONFIG_NFS_V4_1)
227 	init_waitqueue_head(&clp->cl_lock_waitq);
228 #endif
229 	INIT_LIST_HEAD(&clp->pending_cb_stateids);
230 
231 	if (cl_init->minorversion != 0)
232 		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
233 	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
234 	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
235 	if (test_bit(NFS_CS_PNFS, &cl_init->init_flags))
236 		__set_bit(NFS_CS_PNFS, &clp->cl_flags);
237 	if (test_bit(NFS_CS_NETUNREACH_FATAL, &cl_init->init_flags))
238 		__set_bit(NFS_CS_NETUNREACH_FATAL, &clp->cl_flags);
239 	/*
240 	 * Set up the connection to the server before we add add to the
241 	 * global list.
242 	 */
243 	err = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
244 	if (err == -EINVAL)
245 		err = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
246 	if (err < 0)
247 		goto error;
248 
249 	/* If no clientaddr= option was specified, find a usable cb address */
250 	if (ip_addr == NULL) {
251 		struct sockaddr_storage cb_addr;
252 		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
253 
254 		err = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
255 		if (err < 0)
256 			goto error;
257 		err = rpc_ntop(sap, buf, sizeof(buf));
258 		if (err < 0)
259 			goto error;
260 		ip_addr = (const char *)buf;
261 	}
262 	strscpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
263 
264 	err = nfs_idmap_new(clp);
265 	if (err < 0) {
266 		dprintk("%s: failed to create idmapper. Error = %d\n",
267 			__func__, err);
268 		goto error;
269 	}
270 	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
271 	return clp;
272 
273 error:
274 	nfs_free_client(clp);
275 	return ERR_PTR(err);
276 }
277 
278 /*
279  * Destroy the NFS4 callback service
280  */
nfs4_destroy_callback(struct nfs_client * clp)281 static void nfs4_destroy_callback(struct nfs_client *clp)
282 {
283 	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
284 		nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
285 }
286 
nfs4_shutdown_client(struct nfs_client * clp)287 static void nfs4_shutdown_client(struct nfs_client *clp)
288 {
289 	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
290 		nfs4_kill_renewd(clp);
291 	clp->cl_mvops->shutdown_client(clp);
292 	nfs4_destroy_callback(clp);
293 	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
294 		nfs_idmap_delete(clp);
295 
296 	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
297 	kfree(clp->cl_serverowner);
298 	kfree(clp->cl_serverscope);
299 	kfree(clp->cl_implid);
300 	kfree(clp->cl_owner_id);
301 }
302 
nfs4_free_client(struct nfs_client * clp)303 void nfs4_free_client(struct nfs_client *clp)
304 {
305 	nfs4_shutdown_client(clp);
306 	nfs_free_client(clp);
307 }
308 
309 /*
310  * Initialize the NFS4 callback service
311  */
nfs4_init_callback(struct nfs_client * clp)312 static int nfs4_init_callback(struct nfs_client *clp)
313 {
314 	struct rpc_xprt *xprt;
315 	int error;
316 
317 	xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
318 
319 	if (nfs4_has_session(clp)) {
320 		error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
321 		if (error < 0)
322 			return error;
323 	}
324 
325 	error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
326 	if (error < 0) {
327 		dprintk("%s: failed to start callback. Error = %d\n",
328 			__func__, error);
329 		return error;
330 	}
331 	__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
332 
333 	return 0;
334 }
335 
336 /**
337  * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
338  * @clp: nfs_client to initialize
339  *
340  * Returns zero on success, or a negative errno if some error occurred.
341  */
nfs40_init_client(struct nfs_client * clp)342 int nfs40_init_client(struct nfs_client *clp)
343 {
344 	struct nfs4_slot_table *tbl;
345 	int ret;
346 
347 	tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
348 	if (tbl == NULL)
349 		return -ENOMEM;
350 
351 	ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
352 					"NFSv4.0 transport Slot table");
353 	if (ret) {
354 		nfs4_shutdown_slot_table(tbl);
355 		kfree(tbl);
356 		return ret;
357 	}
358 
359 	clp->cl_slot_tbl = tbl;
360 	return 0;
361 }
362 
363 #if defined(CONFIG_NFS_V4_1)
364 
365 /**
366  * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
367  * @clp: nfs_client to initialize
368  *
369  * Returns zero on success, or a negative errno if some error occurred.
370  */
nfs41_init_client(struct nfs_client * clp)371 int nfs41_init_client(struct nfs_client *clp)
372 {
373 	struct nfs4_session *session = NULL;
374 
375 	/*
376 	 * Create the session and mark it expired.
377 	 * When a SEQUENCE operation encounters the expired session
378 	 * it will do session recovery to initialize it.
379 	 */
380 	session = nfs4_alloc_session(clp);
381 	if (!session)
382 		return -ENOMEM;
383 
384 	clp->cl_session = session;
385 
386 	/*
387 	 * The create session reply races with the server back
388 	 * channel probe. Mark the client NFS_CS_SESSION_INITING
389 	 * so that the client back channel can find the
390 	 * nfs_client struct
391 	 */
392 	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
393 	return 0;
394 }
395 
396 #endif	/* CONFIG_NFS_V4_1 */
397 
398 /*
399  * Initialize the minor version specific parts of an NFS4 client record
400  */
nfs4_init_client_minor_version(struct nfs_client * clp)401 static int nfs4_init_client_minor_version(struct nfs_client *clp)
402 {
403 	int ret;
404 
405 	ret = clp->cl_mvops->init_client(clp);
406 	if (ret)
407 		return ret;
408 	return nfs4_init_callback(clp);
409 }
410 
nfs4_add_trunk(struct nfs_client * clp,struct nfs_client * old)411 static void nfs4_add_trunk(struct nfs_client *clp, struct nfs_client *old)
412 {
413 	struct sockaddr_storage clp_addr, old_addr;
414 	struct sockaddr *clp_sap = (struct sockaddr *)&clp_addr;
415 	struct sockaddr *old_sap = (struct sockaddr *)&old_addr;
416 	size_t clp_salen;
417 	struct xprt_create xprt_args = {
418 		.ident = old->cl_proto,
419 		.net = old->cl_net,
420 		.servername = old->cl_hostname,
421 	};
422 	int max_connect = test_bit(NFS_CS_PNFS, &clp->cl_flags) ?
423 		clp->cl_max_connect : old->cl_max_connect;
424 
425 	if (clp->cl_proto != old->cl_proto)
426 		return;
427 	clp_salen = rpc_peeraddr(clp->cl_rpcclient, clp_sap, sizeof(clp_addr));
428 	rpc_peeraddr(old->cl_rpcclient, old_sap, sizeof(old_addr));
429 
430 	if (clp_addr.ss_family != old_addr.ss_family)
431 		return;
432 
433 	xprt_args.dstaddr = clp_sap;
434 	xprt_args.addrlen = clp_salen;
435 
436 	rpc_clnt_add_xprt(old->cl_rpcclient, &xprt_args,
437 			  rpc_clnt_test_and_add_xprt, &max_connect);
438 }
439 
440 /**
441  * nfs4_init_client - Initialise an NFS4 client record
442  *
443  * @clp: nfs_client to initialise
444  * @cl_init: pointer to nfs_client_initdata
445  *
446  * Returns pointer to an NFS client, or an ERR_PTR value.
447  */
nfs4_init_client(struct nfs_client * clp,const struct nfs_client_initdata * cl_init)448 struct nfs_client *nfs4_init_client(struct nfs_client *clp,
449 				    const struct nfs_client_initdata *cl_init)
450 {
451 	struct nfs_client *old;
452 	int error;
453 
454 	if (clp->cl_cons_state == NFS_CS_READY)
455 		/* the client is initialised already */
456 		return clp;
457 
458 	error = nfs4_init_client_minor_version(clp);
459 	if (error < 0)
460 		goto error;
461 
462 	error = nfs4_discover_server_trunking(clp, &old);
463 	if (error < 0)
464 		goto error;
465 
466 	if (clp != old) {
467 		clp->cl_preserve_clid = true;
468 		/*
469 		 * Mark the client as having failed initialization so other
470 		 * processes walking the nfs_client_list in nfs_match_client()
471 		 * won't try to use it.
472 		 */
473 		nfs_mark_client_ready(clp, -EPERM);
474 		if (old->cl_mvops->session_trunk)
475 			nfs4_add_trunk(clp, old);
476 	}
477 	clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
478 	nfs_put_client(clp);
479 	return old;
480 
481 error:
482 	nfs_mark_client_ready(clp, error);
483 	nfs_put_client(clp);
484 	return ERR_PTR(error);
485 }
486 
487 /*
488  * SETCLIENTID just did a callback update with the callback ident in
489  * "drop," but server trunking discovery claims "drop" and "keep" are
490  * actually the same server.  Swap the callback IDs so that "keep"
491  * will continue to use the callback ident the server now knows about,
492  * and so that "keep"'s original callback ident is destroyed when
493  * "drop" is freed.
494  */
nfs4_swap_callback_idents(struct nfs_client * keep,struct nfs_client * drop)495 static void nfs4_swap_callback_idents(struct nfs_client *keep,
496 				      struct nfs_client *drop)
497 {
498 	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
499 	unsigned int save = keep->cl_cb_ident;
500 
501 	if (keep->cl_cb_ident == drop->cl_cb_ident)
502 		return;
503 
504 	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
505 		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
506 
507 	spin_lock(&nn->nfs_client_lock);
508 
509 	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
510 	keep->cl_cb_ident = drop->cl_cb_ident;
511 
512 	idr_replace(&nn->cb_ident_idr, drop, save);
513 	drop->cl_cb_ident = save;
514 
515 	spin_unlock(&nn->nfs_client_lock);
516 }
517 
nfs4_match_client_owner_id(const struct nfs_client * clp1,const struct nfs_client * clp2)518 static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
519 		const struct nfs_client *clp2)
520 {
521 	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
522 		return true;
523 	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
524 }
525 
nfs4_same_verifier(nfs4_verifier * v1,nfs4_verifier * v2)526 static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
527 {
528 	return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
529 }
530 
nfs4_match_client(struct nfs_client * pos,struct nfs_client * new,struct nfs_client ** prev,struct nfs_net * nn)531 static int nfs4_match_client(struct nfs_client  *pos,  struct nfs_client *new,
532 			     struct nfs_client **prev, struct nfs_net *nn)
533 {
534 	int status;
535 
536 	if (pos->rpc_ops != new->rpc_ops)
537 		return 1;
538 
539 	if (pos->cl_minorversion != new->cl_minorversion)
540 		return 1;
541 
542 	/* If "pos" isn't marked ready, we can't trust the
543 	 * remaining fields in "pos", especially the client
544 	 * ID and serverowner fields.  Wait for CREATE_SESSION
545 	 * to finish. */
546 	if (pos->cl_cons_state > NFS_CS_READY) {
547 		refcount_inc(&pos->cl_count);
548 		spin_unlock(&nn->nfs_client_lock);
549 
550 		nfs_put_client(*prev);
551 		*prev = pos;
552 
553 		status = nfs_wait_client_init_complete(pos);
554 		spin_lock(&nn->nfs_client_lock);
555 
556 		if (status < 0)
557 			return status;
558 	}
559 
560 	if (pos->cl_cons_state != NFS_CS_READY)
561 		return 1;
562 
563 	if (pos->cl_clientid != new->cl_clientid)
564 		return 1;
565 
566 	/* NFSv4.1 always uses the uniform string, however someone
567 	 * might switch the uniquifier string on us.
568 	 */
569 	if (!nfs4_match_client_owner_id(pos, new))
570 		return 1;
571 
572 	return 0;
573 }
574 
575 /**
576  * nfs40_walk_client_list - Find server that recognizes a client ID
577  *
578  * @new: nfs_client with client ID to test
579  * @result: OUT: found nfs_client, or new
580  * @cred: credential to use for trunking test
581  *
582  * Returns zero, a negative errno, or a negative NFS4ERR status.
583  * If zero is returned, an nfs_client pointer is planted in "result."
584  *
585  * NB: nfs40_walk_client_list() relies on the new nfs_client being
586  *     the last nfs_client on the list.
587  */
nfs40_walk_client_list(struct nfs_client * new,struct nfs_client ** result,const struct cred * cred)588 int nfs40_walk_client_list(struct nfs_client *new,
589 			   struct nfs_client **result,
590 			   const struct cred *cred)
591 {
592 	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
593 	struct nfs_client *pos, *prev = NULL;
594 	struct nfs4_setclientid_res clid = {
595 		.clientid	= new->cl_clientid,
596 		.confirm	= new->cl_confirm,
597 	};
598 	int status = -NFS4ERR_STALE_CLIENTID;
599 
600 	spin_lock(&nn->nfs_client_lock);
601 	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
602 
603 		if (pos == new)
604 			goto found;
605 
606 		status = nfs4_match_client(pos, new, &prev, nn);
607 		if (status < 0)
608 			goto out_unlock;
609 		if (status != 0)
610 			continue;
611 		/*
612 		 * We just sent a new SETCLIENTID, which should have
613 		 * caused the server to return a new cl_confirm.  So if
614 		 * cl_confirm is the same, then this is a different
615 		 * server that just returned the same cl_confirm by
616 		 * coincidence:
617 		 */
618 		if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
619 						       &new->cl_confirm))
620 			continue;
621 		/*
622 		 * But if the cl_confirm's are different, then the only
623 		 * way that a SETCLIENTID_CONFIRM to pos can succeed is
624 		 * if new and pos point to the same server:
625 		 */
626 found:
627 		refcount_inc(&pos->cl_count);
628 		spin_unlock(&nn->nfs_client_lock);
629 
630 		nfs_put_client(prev);
631 		prev = pos;
632 
633 		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
634 		switch (status) {
635 		case -NFS4ERR_STALE_CLIENTID:
636 			break;
637 		case 0:
638 			nfs4_swap_callback_idents(pos, new);
639 			pos->cl_confirm = new->cl_confirm;
640 			nfs_mark_client_ready(pos, NFS_CS_READY);
641 
642 			prev = NULL;
643 			*result = pos;
644 			goto out;
645 		case -ERESTARTSYS:
646 		case -ETIMEDOUT:
647 			/* The callback path may have been inadvertently
648 			 * changed. Schedule recovery!
649 			 */
650 			nfs4_schedule_path_down_recovery(pos);
651 			goto out;
652 		default:
653 			goto out;
654 		}
655 
656 		spin_lock(&nn->nfs_client_lock);
657 	}
658 out_unlock:
659 	spin_unlock(&nn->nfs_client_lock);
660 
661 	/* No match found. The server lost our clientid */
662 out:
663 	nfs_put_client(prev);
664 	return status;
665 }
666 
667 #ifdef CONFIG_NFS_V4_1
668 /*
669  * Returns true if the server major ids match
670  */
671 bool
nfs4_check_serverowner_major_id(struct nfs41_server_owner * o1,struct nfs41_server_owner * o2)672 nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
673 				struct nfs41_server_owner *o2)
674 {
675 	if (o1->major_id_sz != o2->major_id_sz)
676 		return false;
677 	return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
678 }
679 
680 /*
681  * Returns true if the server scopes match
682  */
683 static bool
nfs4_check_server_scope(struct nfs41_server_scope * s1,struct nfs41_server_scope * s2)684 nfs4_check_server_scope(struct nfs41_server_scope *s1,
685 			struct nfs41_server_scope *s2)
686 {
687 	if (s1->server_scope_sz != s2->server_scope_sz)
688 		return false;
689 	return memcmp(s1->server_scope, s2->server_scope,
690 					s1->server_scope_sz) == 0;
691 }
692 
693 /**
694  * nfs4_detect_session_trunking - Checks for session trunking.
695  * @clp:    original mount nfs_client
696  * @res:    result structure from an exchange_id using the original mount
697  *          nfs_client with a new multi_addr transport
698  * @xprt:   pointer to the transport to add.
699  *
700  * Called after a successful EXCHANGE_ID on a multi-addr connection.
701  * Upon success, add the transport.
702  *
703  * Returns zero on success, otherwise -EINVAL
704  *
705  * Note: since the exchange_id for the new multi_addr transport uses the
706  * same nfs_client from the original mount, the cl_owner_id is reused,
707  * so eir_clientowner is the same.
708  */
nfs4_detect_session_trunking(struct nfs_client * clp,struct nfs41_exchange_id_res * res,struct rpc_xprt * xprt)709 int nfs4_detect_session_trunking(struct nfs_client *clp,
710 				 struct nfs41_exchange_id_res *res,
711 				 struct rpc_xprt *xprt)
712 {
713 	/* Check eir_clientid */
714 	if (clp->cl_clientid != res->clientid)
715 		goto out_err;
716 
717 	/* Check eir_server_owner so_major_id */
718 	if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
719 					     res->server_owner))
720 		goto out_err;
721 
722 	/* Check eir_server_owner so_minor_id */
723 	if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
724 		goto out_err;
725 
726 	/* Check eir_server_scope */
727 	if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
728 		goto out_err;
729 
730 	pr_info("NFS:  %s: Session trunking succeeded for %s\n",
731 		clp->cl_hostname,
732 		xprt->address_strings[RPC_DISPLAY_ADDR]);
733 
734 	return 0;
735 out_err:
736 	pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
737 		xprt->address_strings[RPC_DISPLAY_ADDR]);
738 
739 	return -EINVAL;
740 }
741 
742 /**
743  * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
744  *
745  * @new: nfs_client with client ID to test
746  * @result: OUT: found nfs_client, or new
747  * @cred: credential to use for trunking test
748  *
749  * Returns zero, a negative errno, or a negative NFS4ERR status.
750  * If zero is returned, an nfs_client pointer is planted in "result."
751  *
752  * NB: nfs41_walk_client_list() relies on the new nfs_client being
753  *     the last nfs_client on the list.
754  */
nfs41_walk_client_list(struct nfs_client * new,struct nfs_client ** result,const struct cred * cred)755 int nfs41_walk_client_list(struct nfs_client *new,
756 			   struct nfs_client **result,
757 			   const struct cred *cred)
758 {
759 	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
760 	struct nfs_client *pos, *prev = NULL;
761 	int status = -NFS4ERR_STALE_CLIENTID;
762 
763 	spin_lock(&nn->nfs_client_lock);
764 	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
765 
766 		if (pos == new)
767 			goto found;
768 
769 		status = nfs4_match_client(pos, new, &prev, nn);
770 		if (status < 0)
771 			goto out;
772 		if (status != 0)
773 			continue;
774 
775 		/*
776 		 * Note that session trunking is just a special subcase of
777 		 * client id trunking. In either case, we want to fall back
778 		 * to using the existing nfs_client.
779 		 */
780 		if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
781 						     new->cl_serverowner))
782 			continue;
783 
784 found:
785 		refcount_inc(&pos->cl_count);
786 		*result = pos;
787 		status = 0;
788 		break;
789 	}
790 
791 out:
792 	spin_unlock(&nn->nfs_client_lock);
793 	nfs_put_client(prev);
794 	return status;
795 }
796 #endif	/* CONFIG_NFS_V4_1 */
797 
nfs4_destroy_server(struct nfs_server * server)798 static void nfs4_destroy_server(struct nfs_server *server)
799 {
800 	LIST_HEAD(freeme);
801 
802 	nfs_server_return_all_delegations(server);
803 	unset_pnfs_layoutdriver(server);
804 	nfs4_purge_state_owners(server, &freeme);
805 	nfs4_free_state_owners(&freeme);
806 	kfree(server->delegation_hash_table);
807 }
808 
809 /*
810  * NFSv4.0 callback thread helper
811  *
812  * Find a client by callback identifier
813  */
814 struct nfs_client *
nfs4_find_client_ident(struct net * net,int cb_ident)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 		refcount_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 */
nfs4_cb_match_client(const struct sockaddr * addr,struct nfs_client * clp,u32 minorversion)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 *
nfs4_find_client_sessionid(struct net * net,const struct sockaddr * addr,struct nfs4_sessionid * sid,u32 minorversion)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))
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 		refcount_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 *
nfs4_find_client_sessionid(struct net * net,const struct sockaddr * addr,struct nfs4_sessionid * sid,u32 minorversion)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  */
nfs4_set_client(struct nfs_server * server,struct nfs_client_initdata * cl_init)899 static int nfs4_set_client(struct nfs_server *server,
900 		struct nfs_client_initdata *cl_init)
901 {
902 	struct nfs_client *clp;
903 
904 	cl_init->nfs_mod = &nfs_v4;
905 	cl_init->cred = server->cred;
906 
907 	if (cl_init->minorversion == 0) {
908 		__set_bit(NFS_CS_REUSEPORT, &cl_init->init_flags);
909 		cl_init->max_connect = 0;
910 	}
911 
912 	switch (cl_init->proto) {
913 	case XPRT_TRANSPORT_RDMA:
914 	case XPRT_TRANSPORT_TCP:
915 	case XPRT_TRANSPORT_TCP_TLS:
916 		break;
917 	default:
918 		cl_init->nconnect = 0;
919 	}
920 
921 	if (server->flags & NFS_MOUNT_NORESVPORT)
922 		__set_bit(NFS_CS_NORESVPORT, &cl_init->init_flags);
923 	if (server->options & NFS_OPTION_MIGRATION)
924 		__set_bit(NFS_CS_MIGRATION, &cl_init->init_flags);
925 	if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
926 		__set_bit(NFS_CS_TSM_POSSIBLE, &cl_init->init_flags);
927 	server->port = rpc_get_port((struct sockaddr *)cl_init->addr);
928 
929 	if (server->flags & NFS_MOUNT_NETUNREACH_FATAL)
930 		__set_bit(NFS_CS_NETUNREACH_FATAL, &cl_init->init_flags);
931 
932 	/* Allocate or find a client reference we can use */
933 	clp = nfs_get_client(cl_init);
934 	if (IS_ERR(clp))
935 		return PTR_ERR(clp);
936 
937 	if (server->nfs_client == clp) {
938 		nfs_put_client(clp);
939 		return -ELOOP;
940 	}
941 
942 	/*
943 	 * Query for the lease time on clientid setup or renewal
944 	 *
945 	 * Note that this will be set on nfs_clients that were created
946 	 * only for the DS role and did not set this bit, but now will
947 	 * serve a dual role.
948 	 */
949 	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
950 
951 	server->nfs_client = clp;
952 	nfs_sysfs_add_server(server);
953 	nfs_sysfs_link_rpc_client(server, clp->cl_rpcclient, "_state");
954 
955 	return 0;
956 }
957 
958 /*
959  * Set up a pNFS Data Server client.
960  *
961  * Return any existing nfs_client that matches server address,port,version
962  * and minorversion.
963  *
964  * For a new nfs_client, use a soft mount (default), a low retrans and a
965  * low timeout interval so that if a connection is lost, we retry through
966  * the MDS.
967  */
nfs4_set_ds_client(struct nfs_server * mds_srv,const struct sockaddr_storage * ds_addr,int ds_addrlen,int ds_proto,unsigned int ds_timeo,unsigned int ds_retrans,u32 minor_version)968 struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
969 		const struct sockaddr_storage *ds_addr, int ds_addrlen,
970 		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
971 		u32 minor_version)
972 {
973 	struct rpc_timeout ds_timeout;
974 	struct nfs_client *mds_clp = mds_srv->nfs_client;
975 	struct nfs_client_initdata cl_init = {
976 		.addr = ds_addr,
977 		.addrlen = ds_addrlen,
978 		.nodename = mds_clp->cl_rpcclient->cl_nodename,
979 		.ip_addr = mds_clp->cl_ipaddr,
980 		.nfs_mod = &nfs_v4,
981 		.proto = ds_proto,
982 		.minorversion = minor_version,
983 		.net = mds_clp->cl_net,
984 		.timeparms = &ds_timeout,
985 		.cred = mds_srv->cred,
986 		.xprtsec = mds_srv->nfs_client->cl_xprtsec,
987 	};
988 	char buf[INET6_ADDRSTRLEN + 1];
989 
990 	if (rpc_ntop((struct sockaddr *)ds_addr, buf, sizeof(buf)) <= 0)
991 		return ERR_PTR(-EINVAL);
992 	cl_init.hostname = buf;
993 
994 	switch (ds_proto) {
995 	case XPRT_TRANSPORT_RDMA:
996 	case XPRT_TRANSPORT_TCP:
997 	case XPRT_TRANSPORT_TCP_TLS:
998 		if (mds_clp->cl_nconnect > 1) {
999 			cl_init.nconnect = mds_clp->cl_nconnect;
1000 			cl_init.max_connect = NFS_MAX_TRANSPORTS;
1001 		}
1002 	}
1003 
1004 	if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
1005 		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
1006 	if (test_bit(NFS_CS_NETUNREACH_FATAL, &mds_clp->cl_flags))
1007 		__set_bit(NFS_CS_NETUNREACH_FATAL, &cl_init.init_flags);
1008 
1009 	__set_bit(NFS_CS_PNFS, &cl_init.init_flags);
1010 	cl_init.max_connect = NFS_MAX_TRANSPORTS;
1011 	/*
1012 	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
1013 	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
1014 	 * (section 13.1 RFC 5661).
1015 	 */
1016 	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
1017 	return nfs_get_client(&cl_init);
1018 }
1019 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
1020 
1021 /*
1022  * Session has been established, and the client marked ready.
1023  * Limit the mount rsize, wsize and dtsize using negotiated fore
1024  * channel attributes.
1025  */
nfs4_session_limit_rwsize(struct nfs_server * server)1026 static void nfs4_session_limit_rwsize(struct nfs_server *server)
1027 {
1028 #ifdef CONFIG_NFS_V4_1
1029 	struct nfs4_session *sess;
1030 	u32 server_resp_sz;
1031 	u32 server_rqst_sz;
1032 
1033 	if (!nfs4_has_session(server->nfs_client))
1034 		return;
1035 	sess = server->nfs_client->cl_session;
1036 	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
1037 	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
1038 
1039 	if (server->dtsize > server_resp_sz)
1040 		server->dtsize = server_resp_sz;
1041 	if (server->rsize > server_resp_sz)
1042 		server->rsize = server_resp_sz;
1043 	if (server->wsize > server_rqst_sz)
1044 		server->wsize = server_rqst_sz;
1045 #endif /* CONFIG_NFS_V4_1 */
1046 }
1047 
1048 /*
1049  * Limit xattr sizes using the channel attributes.
1050  */
nfs4_session_limit_xasize(struct nfs_server * server)1051 static void nfs4_session_limit_xasize(struct nfs_server *server)
1052 {
1053 #ifdef CONFIG_NFS_V4_2
1054 	struct nfs4_session *sess;
1055 	u32 server_gxa_sz;
1056 	u32 server_sxa_sz;
1057 	u32 server_lxa_sz;
1058 
1059 	if (!nfs4_has_session(server->nfs_client))
1060 		return;
1061 
1062 	sess = server->nfs_client->cl_session;
1063 
1064 	server_gxa_sz = sess->fc_attrs.max_resp_sz - nfs42_maxgetxattr_overhead;
1065 	server_sxa_sz = sess->fc_attrs.max_rqst_sz - nfs42_maxsetxattr_overhead;
1066 	server_lxa_sz = sess->fc_attrs.max_resp_sz -
1067 	    nfs42_maxlistxattrs_overhead;
1068 
1069 	if (server->gxasize > server_gxa_sz)
1070 		server->gxasize = server_gxa_sz;
1071 	if (server->sxasize > server_sxa_sz)
1072 		server->sxasize = server_sxa_sz;
1073 	if (server->lxasize > server_lxa_sz)
1074 		server->lxasize = server_lxa_sz;
1075 #endif
1076 }
1077 
nfs4_server_common_setup(struct nfs_server * server,struct nfs_fh * mntfh,bool auth_probe)1078 static int nfs4_server_common_setup(struct nfs_server *server,
1079 		struct nfs_fh *mntfh, bool auth_probe)
1080 {
1081 	int error;
1082 
1083 	error = nfs4_delegation_hash_alloc(server);
1084 	if (error)
1085 		return error;
1086 
1087 	/* data servers support only a subset of NFSv4.1 */
1088 	if (is_ds_only_client(server->nfs_client))
1089 		return -EPROTONOSUPPORT;
1090 
1091 	/* We must ensure the session is initialised first */
1092 	error = nfs4_init_session(server->nfs_client);
1093 	if (error < 0)
1094 		return error;
1095 
1096 	nfs_server_set_init_caps(server);
1097 
1098 	/* Probe the root fh to retrieve its FSID and filehandle */
1099 	error = nfs4_get_rootfh(server, mntfh, auth_probe);
1100 	if (error < 0)
1101 		return error;
1102 
1103 	dprintk("Server FSID: %llx:%llx\n",
1104 			(unsigned long long) server->fsid.major,
1105 			(unsigned long long) server->fsid.minor);
1106 	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1107 
1108 	error = nfs_probe_server(server, mntfh);
1109 	if (error < 0)
1110 		return error;
1111 
1112 	nfs4_session_limit_rwsize(server);
1113 	nfs4_session_limit_xasize(server);
1114 
1115 	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1116 		server->namelen = NFS4_MAXNAMLEN;
1117 
1118 	nfs_server_insert_lists(server);
1119 	server->mount_time = jiffies;
1120 	server->destroy = nfs4_destroy_server;
1121 	return 0;
1122 }
1123 
1124 /*
1125  * Create a version 4 volume record
1126  */
nfs4_init_server(struct nfs_server * server,struct fs_context * fc)1127 static int nfs4_init_server(struct nfs_server *server, struct fs_context *fc)
1128 {
1129 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1130 	struct rpc_timeout timeparms;
1131 	struct nfs_client_initdata cl_init = {
1132 		.hostname = ctx->nfs_server.hostname,
1133 		.addr = &ctx->nfs_server._address,
1134 		.addrlen = ctx->nfs_server.addrlen,
1135 		.ip_addr = ctx->client_address,
1136 		.proto = ctx->nfs_server.protocol,
1137 		.minorversion = ctx->minorversion,
1138 		.net = fc->net_ns,
1139 		.timeparms = &timeparms,
1140 		.xprtsec = ctx->xprtsec,
1141 		.nconnect = ctx->nfs_server.nconnect,
1142 		.max_connect = ctx->nfs_server.max_connect,
1143 	};
1144 	int error;
1145 
1146 	nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
1147 				ctx->timeo, ctx->retrans);
1148 
1149 	/* Initialise the client representation from the mount data */
1150 	server->flags = ctx->flags;
1151 	server->options = ctx->options;
1152 	server->auth_info = ctx->auth_info;
1153 
1154 	/* Use the first specified auth flavor. If this flavor isn't
1155 	 * allowed by the server, use the SECINFO path to try the
1156 	 * other specified flavors */
1157 	if (ctx->auth_info.flavor_len >= 1)
1158 		ctx->selected_flavor = ctx->auth_info.flavors[0];
1159 	else
1160 		ctx->selected_flavor = RPC_AUTH_UNIX;
1161 
1162 	/* Get a client record */
1163 	error = nfs4_set_client(server, &cl_init);
1164 	if (error < 0)
1165 		return error;
1166 
1167 	if (ctx->rsize)
1168 		server->rsize = nfs_io_size(ctx->rsize, server->nfs_client->cl_proto);
1169 	if (ctx->wsize)
1170 		server->wsize = nfs_io_size(ctx->wsize, server->nfs_client->cl_proto);
1171 
1172 	server->acregmin = ctx->acregmin * HZ;
1173 	server->acregmax = ctx->acregmax * HZ;
1174 	server->acdirmin = ctx->acdirmin * HZ;
1175 	server->acdirmax = ctx->acdirmax * HZ;
1176 	server->port     = ctx->nfs_server.port;
1177 
1178 	return nfs_init_server_rpcclient(server, &timeparms,
1179 					 ctx->selected_flavor);
1180 }
1181 
1182 /*
1183  * Create a version 4 volume record
1184  * - keyed on server and FSID
1185  */
nfs4_create_server(struct fs_context * fc)1186 struct nfs_server *nfs4_create_server(struct fs_context *fc)
1187 {
1188 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1189 	struct nfs_server *server;
1190 	bool auth_probe;
1191 	int error;
1192 
1193 	server = nfs_alloc_server();
1194 	if (!server)
1195 		return ERR_PTR(-ENOMEM);
1196 
1197 	server->cred = get_cred(fc->cred);
1198 
1199 	auth_probe = ctx->auth_info.flavor_len < 1;
1200 
1201 	/* set up the general RPC client */
1202 	error = nfs4_init_server(server, fc);
1203 	if (error < 0)
1204 		goto error;
1205 
1206 	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1207 	if (error < 0)
1208 		goto error;
1209 
1210 	return server;
1211 
1212 error:
1213 	nfs_free_server(server);
1214 	return ERR_PTR(error);
1215 }
1216 
1217 /*
1218  * Create an NFS4 referral server record
1219  */
nfs4_create_referral_server(struct fs_context * fc)1220 struct nfs_server *nfs4_create_referral_server(struct fs_context *fc)
1221 {
1222 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1223 	struct nfs_server *parent_server = NFS_SB(ctx->clone_data.sb);
1224 	struct nfs_client *parent_client = parent_server->nfs_client;
1225 	struct nfs_client_initdata cl_init = {
1226 		.hostname = ctx->nfs_server.hostname,
1227 		.addr = &ctx->nfs_server._address,
1228 		.addrlen = ctx->nfs_server.addrlen,
1229 		.ip_addr = parent_client->cl_ipaddr,
1230 		.minorversion = parent_client->cl_mvops->minor_version,
1231 		.net = parent_client->cl_net,
1232 		.timeparms = parent_server->client->cl_timeout,
1233 		.xprtsec = parent_client->cl_xprtsec,
1234 		.nconnect = parent_client->cl_nconnect,
1235 		.max_connect = parent_client->cl_max_connect,
1236 	};
1237 	struct nfs_server *server;
1238 	bool auth_probe;
1239 	int error;
1240 
1241 	server = nfs_alloc_server();
1242 	if (!server)
1243 		return ERR_PTR(-ENOMEM);
1244 
1245 	server->cred = get_cred(parent_server->cred);
1246 
1247 	/* Initialise the client representation from the parent server */
1248 	nfs_server_copy_userdata(server, parent_server);
1249 
1250 	/* Get a client representation */
1251 #if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1252 	rpc_set_port(&ctx->nfs_server.address, NFS_RDMA_PORT);
1253 	cl_init.proto = XPRT_TRANSPORT_RDMA;
1254 	error = nfs4_set_client(server, &cl_init);
1255 	if (!error)
1256 		goto init_server;
1257 #endif	/* IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA) */
1258 
1259 	cl_init.proto = XPRT_TRANSPORT_TCP;
1260 	if (parent_client->cl_xprtsec.policy != RPC_XPRTSEC_NONE)
1261 		cl_init.proto = XPRT_TRANSPORT_TCP_TLS;
1262 	rpc_set_port(&ctx->nfs_server.address, NFS_PORT);
1263 	error = nfs4_set_client(server, &cl_init);
1264 	if (error < 0)
1265 		goto error;
1266 
1267 #if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1268 init_server:
1269 #endif
1270 	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout,
1271 					  ctx->selected_flavor);
1272 	if (error < 0)
1273 		goto error;
1274 
1275 	auth_probe = parent_server->auth_info.flavor_len < 1;
1276 
1277 	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1278 	if (error < 0)
1279 		goto error;
1280 
1281 	return server;
1282 
1283 error:
1284 	nfs_free_server(server);
1285 	return ERR_PTR(error);
1286 }
1287 
1288 /**
1289  * nfs4_update_server - Move an nfs_server to a different nfs_client
1290  *
1291  * @server: represents FSID to be moved
1292  * @hostname: new end-point's hostname
1293  * @sap: new end-point's socket address
1294  * @salen: size of "sap"
1295  * @net: net namespace
1296  *
1297  * The nfs_server must be quiescent before this function is invoked.
1298  * Either its session is drained (NFSv4.1+), or its transport is
1299  * plugged and drained (NFSv4.0).
1300  *
1301  * Returns zero on success, or a negative errno value.
1302  */
nfs4_update_server(struct nfs_server * server,const char * hostname,struct sockaddr_storage * sap,size_t salen,struct net * net)1303 int nfs4_update_server(struct nfs_server *server, const char *hostname,
1304 		       struct sockaddr_storage *sap, size_t salen, struct net *net)
1305 {
1306 	struct nfs_client *clp = server->nfs_client;
1307 	struct rpc_clnt *clnt = server->client;
1308 	struct xprt_create xargs = {
1309 		.ident		= clp->cl_proto,
1310 		.net		= net,
1311 		.dstaddr	= (struct sockaddr *)sap,
1312 		.addrlen	= salen,
1313 		.servername	= hostname,
1314 		/* cel: bleh. We might need to pass TLS parameters here */
1315 	};
1316 	char buf[INET6_ADDRSTRLEN + 1];
1317 	struct sockaddr_storage address;
1318 	struct sockaddr *localaddr = (struct sockaddr *)&address;
1319 	struct nfs_client_initdata cl_init = {
1320 		.hostname = hostname,
1321 		.addr = sap,
1322 		.addrlen = salen,
1323 		.ip_addr = buf,
1324 		.proto = clp->cl_proto,
1325 		.minorversion = clp->cl_minorversion,
1326 		.net = net,
1327 		.timeparms = clnt->cl_timeout,
1328 		.xprtsec = clp->cl_xprtsec,
1329 		.nconnect = clp->cl_nconnect,
1330 		.max_connect = clp->cl_max_connect,
1331 	};
1332 	int error;
1333 
1334 	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1335 	if (error != 0)
1336 		return error;
1337 
1338 	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1339 	if (error != 0)
1340 		return error;
1341 
1342 	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
1343 		return -EAFNOSUPPORT;
1344 
1345 	nfs_server_remove_lists(server);
1346 	set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1347 	error = nfs4_set_client(server, &cl_init);
1348 	clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1349 	if (error != 0) {
1350 		nfs_server_insert_lists(server);
1351 		return error;
1352 	}
1353 	nfs_put_client(clp);
1354 
1355 	if (server->nfs_client->cl_hostname == NULL) {
1356 		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1357 		if (server->nfs_client->cl_hostname == NULL)
1358 			return -ENOMEM;
1359 	}
1360 	nfs_server_insert_lists(server);
1361 
1362 	return nfs_probe_server(server, NFS_FH(d_inode(server->super->s_root)));
1363 }
1364