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v5.9
   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
  22#define NFSDBG_FACILITY		NFSDBG_CLIENT
  23
  24/*
  25 * Get a unique NFSv4.0 callback identifier which will be used
  26 * by the V4.0 callback service to lookup the nfs_client struct
  27 */
  28static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
  29{
  30	int ret = 0;
  31	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  32
  33	if (clp->rpc_ops->version != 4 || minorversion != 0)
  34		return ret;
  35	idr_preload(GFP_KERNEL);
  36	spin_lock(&nn->nfs_client_lock);
  37	ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
  38	if (ret >= 0)
  39		clp->cl_cb_ident = ret;
  40	spin_unlock(&nn->nfs_client_lock);
  41	idr_preload_end();
  42	return ret < 0 ? ret : 0;
  43}
  44
  45#ifdef CONFIG_NFS_V4_1
  46/*
  47 * Per auth flavor data server rpc clients
  48 */
  49struct nfs4_ds_server {
  50	struct list_head	list;   /* ds_clp->cl_ds_clients */
  51	struct rpc_clnt		*rpc_clnt;
  52};
  53
  54/**
  55 * nfs4_find_ds_client - Common lookup case for DS I/O
  56 * @ds_clp: pointer to the DS's nfs_client
  57 * @flavor: rpc auth flavour to match
  58 */
  59static struct nfs4_ds_server *
  60nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  61{
  62	struct nfs4_ds_server *dss;
  63
  64	rcu_read_lock();
  65	list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
  66		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  67			continue;
  68		goto out;
  69	}
  70	dss = NULL;
  71out:
  72	rcu_read_unlock();
  73	return dss;
  74}
  75
  76static struct nfs4_ds_server *
  77nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
  78			   struct nfs4_ds_server *new)
  79{
  80	struct nfs4_ds_server *dss;
  81
  82	spin_lock(&ds_clp->cl_lock);
  83	list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
  84		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  85			continue;
  86		goto out;
  87	}
  88	if (new)
  89		list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
  90	dss = new;
  91out:
  92	spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
  93	return dss;
  94}
  95
  96static struct nfs4_ds_server *
  97nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  98{
  99	struct nfs4_ds_server *dss;
 100
 101	dss = kmalloc(sizeof(*dss), GFP_NOFS);
 102	if (dss == NULL)
 103		return ERR_PTR(-ENOMEM);
 104
 105	dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
 106	if (IS_ERR(dss->rpc_clnt)) {
 107		int err = PTR_ERR(dss->rpc_clnt);
 108		kfree (dss);
 109		return ERR_PTR(err);
 110	}
 111	INIT_LIST_HEAD(&dss->list);
 112
 113	return dss;
 114}
 115
 116static void
 117nfs4_free_ds_server(struct nfs4_ds_server *dss)
 118{
 119	rpc_release_client(dss->rpc_clnt);
 120	kfree(dss);
 121}
 122
 123/**
 124 * nfs4_find_or_create_ds_client - Find or create a DS rpc client
 125 * @ds_clp: pointer to the DS's nfs_client
 126 * @inode: pointer to the inode
 127 *
 128 * Find or create a DS rpc client with th MDS server rpc client auth flavor
 129 * in the nfs_client cl_ds_clients list.
 130 */
 131struct rpc_clnt *
 132nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
 133{
 134	struct nfs4_ds_server *dss, *new;
 135	rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
 136
 137	dss = nfs4_find_ds_client(ds_clp, flavor);
 138	if (dss != NULL)
 139		goto out;
 140	new = nfs4_alloc_ds_server(ds_clp, flavor);
 141	if (IS_ERR(new))
 142		return ERR_CAST(new);
 143	dss = nfs4_add_ds_client(ds_clp, flavor, new);
 144	if (dss != new)
 145		nfs4_free_ds_server(new);
 146out:
 147	return dss->rpc_clnt;
 148}
 149EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
 150
 151static void
 152nfs4_shutdown_ds_clients(struct nfs_client *clp)
 153{
 154	struct nfs4_ds_server *dss;
 155
 156	while (!list_empty(&clp->cl_ds_clients)) {
 157		dss = list_entry(clp->cl_ds_clients.next,
 158					struct nfs4_ds_server, list);
 159		list_del(&dss->list);
 160		rpc_shutdown_client(dss->rpc_clnt);
 161		kfree (dss);
 162	}
 163}
 164
 165static void
 166nfs4_cleanup_callback(struct nfs_client *clp)
 167{
 168	struct nfs4_copy_state *cp_state;
 169
 170	while (!list_empty(&clp->pending_cb_stateids)) {
 171		cp_state = list_entry(clp->pending_cb_stateids.next,
 172					struct nfs4_copy_state, copies);
 173		list_del(&cp_state->copies);
 174		kfree(cp_state);
 175	}
 176}
 177
 178void nfs41_shutdown_client(struct nfs_client *clp)
 179{
 180	if (nfs4_has_session(clp)) {
 181		nfs4_cleanup_callback(clp);
 182		nfs4_shutdown_ds_clients(clp);
 183		nfs4_destroy_session(clp->cl_session);
 184		nfs4_destroy_clientid(clp);
 185	}
 186
 187}
 188#endif	/* CONFIG_NFS_V4_1 */
 189
 190void nfs40_shutdown_client(struct nfs_client *clp)
 191{
 192	if (clp->cl_slot_tbl) {
 193		nfs4_shutdown_slot_table(clp->cl_slot_tbl);
 194		kfree(clp->cl_slot_tbl);
 195	}
 196}
 197
 198struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
 199{
 200	int err;
 
 201	struct nfs_client *clp = nfs_alloc_client(cl_init);
 
 
 202	if (IS_ERR(clp))
 203		return clp;
 204
 205	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
 206	if (err)
 207		goto error;
 208
 209	if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
 210		err = -EINVAL;
 211		goto error;
 212	}
 213
 214	spin_lock_init(&clp->cl_lock);
 215	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
 216	INIT_LIST_HEAD(&clp->cl_ds_clients);
 217	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
 218	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 219	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 220	clp->cl_mig_gen = 1;
 221#if IS_ENABLED(CONFIG_NFS_V4_1)
 222	init_waitqueue_head(&clp->cl_lock_waitq);
 223#endif
 224	INIT_LIST_HEAD(&clp->pending_cb_stateids);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 225	return clp;
 226
 227error:
 228	nfs_free_client(clp);
 229	return ERR_PTR(err);
 230}
 231
 232/*
 233 * Destroy the NFS4 callback service
 234 */
 235static void nfs4_destroy_callback(struct nfs_client *clp)
 236{
 237	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 238		nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 239}
 240
 241static void nfs4_shutdown_client(struct nfs_client *clp)
 242{
 243	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 244		nfs4_kill_renewd(clp);
 245	clp->cl_mvops->shutdown_client(clp);
 246	nfs4_destroy_callback(clp);
 247	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 248		nfs_idmap_delete(clp);
 249
 250	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 251	kfree(clp->cl_serverowner);
 252	kfree(clp->cl_serverscope);
 253	kfree(clp->cl_implid);
 254	kfree(clp->cl_owner_id);
 255}
 256
 257void nfs4_free_client(struct nfs_client *clp)
 258{
 259	nfs4_shutdown_client(clp);
 260	nfs_free_client(clp);
 261}
 262
 263/*
 264 * Initialize the NFS4 callback service
 265 */
 266static int nfs4_init_callback(struct nfs_client *clp)
 267{
 268	struct rpc_xprt *xprt;
 269	int error;
 270
 271	xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
 272
 273	if (nfs4_has_session(clp)) {
 274		error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
 275		if (error < 0)
 276			return error;
 277	}
 278
 279	error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
 280	if (error < 0) {
 281		dprintk("%s: failed to start callback. Error = %d\n",
 282			__func__, error);
 283		return error;
 284	}
 285	__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 286
 287	return 0;
 288}
 289
 290/**
 291 * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
 292 * @clp: nfs_client to initialize
 293 *
 294 * Returns zero on success, or a negative errno if some error occurred.
 295 */
 296int nfs40_init_client(struct nfs_client *clp)
 297{
 298	struct nfs4_slot_table *tbl;
 299	int ret;
 300
 301	tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
 302	if (tbl == NULL)
 303		return -ENOMEM;
 304
 305	ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
 306					"NFSv4.0 transport Slot table");
 307	if (ret) {
 308		kfree(tbl);
 309		return ret;
 310	}
 311
 312	clp->cl_slot_tbl = tbl;
 313	return 0;
 314}
 315
 316#if defined(CONFIG_NFS_V4_1)
 317
 318/**
 319 * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 320 * @clp: nfs_client to initialize
 321 *
 322 * Returns zero on success, or a negative errno if some error occurred.
 323 */
 324int nfs41_init_client(struct nfs_client *clp)
 325{
 326	struct nfs4_session *session = NULL;
 327
 328	/*
 329	 * Create the session and mark it expired.
 330	 * When a SEQUENCE operation encounters the expired session
 331	 * it will do session recovery to initialize it.
 332	 */
 333	session = nfs4_alloc_session(clp);
 334	if (!session)
 335		return -ENOMEM;
 336
 337	clp->cl_session = session;
 338
 339	/*
 340	 * The create session reply races with the server back
 341	 * channel probe. Mark the client NFS_CS_SESSION_INITING
 342	 * so that the client back channel can find the
 343	 * nfs_client struct
 344	 */
 345	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 346	return 0;
 347}
 348
 349#endif	/* CONFIG_NFS_V4_1 */
 350
 351/*
 352 * Initialize the minor version specific parts of an NFS4 client record
 353 */
 354static int nfs4_init_client_minor_version(struct nfs_client *clp)
 355{
 356	int ret;
 357
 358	ret = clp->cl_mvops->init_client(clp);
 359	if (ret)
 360		return ret;
 361	return nfs4_init_callback(clp);
 362}
 363
 364/**
 365 * nfs4_init_client - Initialise an NFS4 client record
 366 *
 367 * @clp: nfs_client to initialise
 368 * @cl_init: pointer to nfs_client_initdata
 369 *
 370 * Returns pointer to an NFS client, or an ERR_PTR value.
 371 */
 372struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 373				    const struct nfs_client_initdata *cl_init)
 374{
 375	char buf[INET6_ADDRSTRLEN + 1];
 376	const char *ip_addr = cl_init->ip_addr;
 377	struct nfs_client *old;
 378	int error;
 379
 380	if (clp->cl_cons_state == NFS_CS_READY)
 381		/* the client is initialised already */
 382		return clp;
 383
 384	/* Check NFS protocol revision and initialize RPC op vector */
 385	clp->rpc_ops = &nfs_v4_clientops;
 386
 387	if (clp->cl_minorversion != 0)
 388		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 389	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
 390	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 391
 392	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
 393	if (error == -EINVAL)
 394		error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
 395	if (error < 0)
 396		goto error;
 397
 398	/* If no clientaddr= option was specified, find a usable cb address */
 399	if (ip_addr == NULL) {
 400		struct sockaddr_storage cb_addr;
 401		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
 402
 403		error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
 404		if (error < 0)
 405			goto error;
 406		error = rpc_ntop(sap, buf, sizeof(buf));
 407		if (error < 0)
 408			goto error;
 409		ip_addr = (const char *)buf;
 410	}
 411	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 412
 413	error = nfs_idmap_new(clp);
 414	if (error < 0) {
 415		dprintk("%s: failed to create idmapper. Error = %d\n",
 416			__func__, error);
 417		goto error;
 418	}
 419	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 420
 421	error = nfs4_init_client_minor_version(clp);
 422	if (error < 0)
 423		goto error;
 424
 425	error = nfs4_discover_server_trunking(clp, &old);
 426	if (error < 0)
 427		goto error;
 428
 429	if (clp != old) {
 430		clp->cl_preserve_clid = true;
 431		/*
 432		 * Mark the client as having failed initialization so other
 433		 * processes walking the nfs_client_list in nfs_match_client()
 434		 * won't try to use it.
 435		 */
 436		nfs_mark_client_ready(clp, -EPERM);
 437	}
 438	nfs_put_client(clp);
 439	clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
 
 440	return old;
 441
 442error:
 443	nfs_mark_client_ready(clp, error);
 444	nfs_put_client(clp);
 445	return ERR_PTR(error);
 446}
 447
 448/*
 449 * SETCLIENTID just did a callback update with the callback ident in
 450 * "drop," but server trunking discovery claims "drop" and "keep" are
 451 * actually the same server.  Swap the callback IDs so that "keep"
 452 * will continue to use the callback ident the server now knows about,
 453 * and so that "keep"'s original callback ident is destroyed when
 454 * "drop" is freed.
 455 */
 456static void nfs4_swap_callback_idents(struct nfs_client *keep,
 457				      struct nfs_client *drop)
 458{
 459	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
 460	unsigned int save = keep->cl_cb_ident;
 461
 462	if (keep->cl_cb_ident == drop->cl_cb_ident)
 463		return;
 464
 465	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
 466		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
 467
 468	spin_lock(&nn->nfs_client_lock);
 469
 470	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
 471	keep->cl_cb_ident = drop->cl_cb_ident;
 472
 473	idr_replace(&nn->cb_ident_idr, drop, save);
 474	drop->cl_cb_ident = save;
 475
 476	spin_unlock(&nn->nfs_client_lock);
 477}
 478
 479static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
 480		const struct nfs_client *clp2)
 481{
 482	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
 483		return true;
 484	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
 485}
 486
 487static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
 488{
 489	return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
 490}
 491
 492static int nfs4_match_client(struct nfs_client  *pos,  struct nfs_client *new,
 493			     struct nfs_client **prev, struct nfs_net *nn)
 494{
 495	int status;
 496
 497	if (pos->rpc_ops != new->rpc_ops)
 498		return 1;
 499
 500	if (pos->cl_minorversion != new->cl_minorversion)
 501		return 1;
 502
 503	/* If "pos" isn't marked ready, we can't trust the
 504	 * remaining fields in "pos", especially the client
 505	 * ID and serverowner fields.  Wait for CREATE_SESSION
 506	 * to finish. */
 507	if (pos->cl_cons_state > NFS_CS_READY) {
 508		refcount_inc(&pos->cl_count);
 509		spin_unlock(&nn->nfs_client_lock);
 510
 511		nfs_put_client(*prev);
 512		*prev = pos;
 513
 514		status = nfs_wait_client_init_complete(pos);
 515		spin_lock(&nn->nfs_client_lock);
 516
 517		if (status < 0)
 518			return status;
 519	}
 520
 521	if (pos->cl_cons_state != NFS_CS_READY)
 522		return 1;
 523
 524	if (pos->cl_clientid != new->cl_clientid)
 525		return 1;
 526
 527	/* NFSv4.1 always uses the uniform string, however someone
 528	 * might switch the uniquifier string on us.
 529	 */
 530	if (!nfs4_match_client_owner_id(pos, new))
 531		return 1;
 532
 533	return 0;
 534}
 535
 536/**
 537 * nfs40_walk_client_list - Find server that recognizes a client ID
 538 *
 539 * @new: nfs_client with client ID to test
 540 * @result: OUT: found nfs_client, or new
 541 * @cred: credential to use for trunking test
 542 *
 543 * Returns zero, a negative errno, or a negative NFS4ERR status.
 544 * If zero is returned, an nfs_client pointer is planted in "result."
 545 *
 546 * NB: nfs40_walk_client_list() relies on the new nfs_client being
 547 *     the last nfs_client on the list.
 548 */
 549int nfs40_walk_client_list(struct nfs_client *new,
 550			   struct nfs_client **result,
 551			   const struct cred *cred)
 552{
 553	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 554	struct nfs_client *pos, *prev = NULL;
 555	struct nfs4_setclientid_res clid = {
 556		.clientid	= new->cl_clientid,
 557		.confirm	= new->cl_confirm,
 558	};
 559	int status = -NFS4ERR_STALE_CLIENTID;
 560
 561	spin_lock(&nn->nfs_client_lock);
 562	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 563
 564		if (pos == new)
 565			goto found;
 566
 567		status = nfs4_match_client(pos, new, &prev, nn);
 568		if (status < 0)
 569			goto out_unlock;
 570		if (status != 0)
 571			continue;
 572		/*
 573		 * We just sent a new SETCLIENTID, which should have
 574		 * caused the server to return a new cl_confirm.  So if
 575		 * cl_confirm is the same, then this is a different
 576		 * server that just returned the same cl_confirm by
 577		 * coincidence:
 578		 */
 579		if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
 580						       &new->cl_confirm))
 581			continue;
 582		/*
 583		 * But if the cl_confirm's are different, then the only
 584		 * way that a SETCLIENTID_CONFIRM to pos can succeed is
 585		 * if new and pos point to the same server:
 586		 */
 587found:
 588		refcount_inc(&pos->cl_count);
 589		spin_unlock(&nn->nfs_client_lock);
 590
 591		nfs_put_client(prev);
 592		prev = pos;
 593
 594		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 595		switch (status) {
 596		case -NFS4ERR_STALE_CLIENTID:
 597			break;
 598		case 0:
 599			nfs4_swap_callback_idents(pos, new);
 600			pos->cl_confirm = new->cl_confirm;
 601			nfs_mark_client_ready(pos, NFS_CS_READY);
 602
 603			prev = NULL;
 604			*result = pos;
 605			goto out;
 606		case -ERESTARTSYS:
 607		case -ETIMEDOUT:
 608			/* The callback path may have been inadvertently
 609			 * changed. Schedule recovery!
 610			 */
 611			nfs4_schedule_path_down_recovery(pos);
 
 612		default:
 613			goto out;
 614		}
 615
 616		spin_lock(&nn->nfs_client_lock);
 617	}
 618out_unlock:
 619	spin_unlock(&nn->nfs_client_lock);
 620
 621	/* No match found. The server lost our clientid */
 622out:
 623	nfs_put_client(prev);
 624	return status;
 625}
 626
 627#ifdef CONFIG_NFS_V4_1
 628/*
 629 * Returns true if the server major ids match
 630 */
 631bool
 632nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
 633				struct nfs41_server_owner *o2)
 634{
 635	if (o1->major_id_sz != o2->major_id_sz)
 636		return false;
 637	return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
 638}
 639
 640/*
 641 * Returns true if the server scopes match
 642 */
 643static bool
 644nfs4_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		return false;
 649	return memcmp(s1->server_scope, s2->server_scope,
 650					s1->server_scope_sz) == 0;
 651}
 652
 653/**
 654 * nfs4_detect_session_trunking - Checks for session trunking.
 655 * @clp:    original mount nfs_client
 656 * @res:    result structure from an exchange_id using the original mount
 657 *          nfs_client with a new multi_addr transport
 658 * @xprt:   pointer to the transport to add.
 659 *
 660 * Called after a successful EXCHANGE_ID on a multi-addr connection.
 661 * Upon success, add the transport.
 662 *
 663 * Returns zero on success, otherwise -EINVAL
 664 *
 665 * Note: since the exchange_id for the new multi_addr transport uses the
 666 * same nfs_client from the original mount, the cl_owner_id is reused,
 667 * so eir_clientowner is the same.
 668 */
 669int nfs4_detect_session_trunking(struct nfs_client *clp,
 670				 struct nfs41_exchange_id_res *res,
 671				 struct rpc_xprt *xprt)
 672{
 673	/* Check eir_clientid */
 674	if (clp->cl_clientid != res->clientid)
 675		goto out_err;
 676
 677	/* Check eir_server_owner so_major_id */
 678	if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
 679					     res->server_owner))
 680		goto out_err;
 681
 682	/* Check eir_server_owner so_minor_id */
 683	if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
 684		goto out_err;
 685
 686	/* Check eir_server_scope */
 687	if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
 688		goto out_err;
 689
 690	pr_info("NFS:  %s: Session trunking succeeded for %s\n",
 691		clp->cl_hostname,
 692		xprt->address_strings[RPC_DISPLAY_ADDR]);
 693
 694	return 0;
 695out_err:
 696	pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
 697		xprt->address_strings[RPC_DISPLAY_ADDR]);
 698
 699	return -EINVAL;
 700}
 701
 702/**
 703 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 704 *
 705 * @new: nfs_client with client ID to test
 706 * @result: OUT: found nfs_client, or new
 707 * @cred: credential to use for trunking test
 708 *
 709 * Returns zero, a negative errno, or a negative NFS4ERR status.
 710 * If zero is returned, an nfs_client pointer is planted in "result."
 711 *
 712 * NB: nfs41_walk_client_list() relies on the new nfs_client being
 713 *     the last nfs_client on the list.
 714 */
 715int nfs41_walk_client_list(struct nfs_client *new,
 716			   struct nfs_client **result,
 717			   const struct cred *cred)
 718{
 719	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 720	struct nfs_client *pos, *prev = NULL;
 721	int status = -NFS4ERR_STALE_CLIENTID;
 722
 723	spin_lock(&nn->nfs_client_lock);
 724	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 725
 726		if (pos == new)
 727			goto found;
 728
 729		status = nfs4_match_client(pos, new, &prev, nn);
 730		if (status < 0)
 731			goto out;
 732		if (status != 0)
 733			continue;
 734
 735		/*
 736		 * Note that session trunking is just a special subcase of
 737		 * client id trunking. In either case, we want to fall back
 738		 * to using the existing nfs_client.
 739		 */
 740		if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
 741						     new->cl_serverowner))
 742			continue;
 743
 744found:
 745		refcount_inc(&pos->cl_count);
 746		*result = pos;
 747		status = 0;
 748		break;
 749	}
 750
 751out:
 752	spin_unlock(&nn->nfs_client_lock);
 753	nfs_put_client(prev);
 754	return status;
 755}
 756#endif	/* CONFIG_NFS_V4_1 */
 757
 758static void nfs4_destroy_server(struct nfs_server *server)
 759{
 760	LIST_HEAD(freeme);
 761
 762	nfs_server_return_all_delegations(server);
 763	unset_pnfs_layoutdriver(server);
 764	nfs4_purge_state_owners(server, &freeme);
 765	nfs4_free_state_owners(&freeme);
 766}
 767
 768/*
 769 * NFSv4.0 callback thread helper
 770 *
 771 * Find a client by callback identifier
 772 */
 773struct nfs_client *
 774nfs4_find_client_ident(struct net *net, int cb_ident)
 775{
 776	struct nfs_client *clp;
 777	struct nfs_net *nn = net_generic(net, nfs_net_id);
 778
 779	spin_lock(&nn->nfs_client_lock);
 780	clp = idr_find(&nn->cb_ident_idr, cb_ident);
 781	if (clp)
 782		refcount_inc(&clp->cl_count);
 783	spin_unlock(&nn->nfs_client_lock);
 784	return clp;
 785}
 786
 787#if defined(CONFIG_NFS_V4_1)
 788/* Common match routine for v4.0 and v4.1 callback services */
 789static bool nfs4_cb_match_client(const struct sockaddr *addr,
 790		struct nfs_client *clp, u32 minorversion)
 791{
 792	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 793
 794	/* Don't match clients that failed to initialise */
 795	if (!(clp->cl_cons_state == NFS_CS_READY ||
 796	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
 797		return false;
 798
 799	smp_rmb();
 800
 801	/* Match the version and minorversion */
 802	if (clp->rpc_ops->version != 4 ||
 803	    clp->cl_minorversion != minorversion)
 804		return false;
 805
 806	/* Match only the IP address, not the port number */
 807	return rpc_cmp_addr(addr, clap);
 808}
 809
 810/*
 811 * NFSv4.1 callback thread helper
 812 * For CB_COMPOUND calls, find a client by IP address, protocol version,
 813 * minorversion, and sessionID
 814 *
 815 * Returns NULL if no such client
 816 */
 817struct nfs_client *
 818nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 819			   struct nfs4_sessionid *sid, u32 minorversion)
 820{
 821	struct nfs_client *clp;
 822	struct nfs_net *nn = net_generic(net, nfs_net_id);
 823
 824	spin_lock(&nn->nfs_client_lock);
 825	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 826		if (!nfs4_cb_match_client(addr, clp, minorversion))
 827			continue;
 828
 829		if (!nfs4_has_session(clp))
 830			continue;
 831
 832		/* Match sessionid*/
 833		if (memcmp(clp->cl_session->sess_id.data,
 834		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 835			continue;
 836
 837		refcount_inc(&clp->cl_count);
 838		spin_unlock(&nn->nfs_client_lock);
 839		return clp;
 840	}
 841	spin_unlock(&nn->nfs_client_lock);
 842	return NULL;
 843}
 844
 845#else /* CONFIG_NFS_V4_1 */
 846
 847struct nfs_client *
 848nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 849			   struct nfs4_sessionid *sid, u32 minorversion)
 850{
 851	return NULL;
 852}
 853#endif /* CONFIG_NFS_V4_1 */
 854
 855/*
 856 * Set up an NFS4 client
 857 */
 858static int nfs4_set_client(struct nfs_server *server,
 859		const char *hostname,
 860		const struct sockaddr *addr,
 861		const size_t addrlen,
 862		const char *ip_addr,
 863		int proto, const struct rpc_timeout *timeparms,
 864		u32 minorversion, unsigned int nconnect,
 865		struct net *net)
 866{
 867	struct nfs_client_initdata cl_init = {
 868		.hostname = hostname,
 869		.addr = addr,
 870		.addrlen = addrlen,
 871		.ip_addr = ip_addr,
 872		.nfs_mod = &nfs_v4,
 873		.proto = proto,
 874		.minorversion = minorversion,
 875		.net = net,
 876		.timeparms = timeparms,
 877		.cred = server->cred,
 878	};
 879	struct nfs_client *clp;
 880
 881	if (minorversion == 0)
 882		__set_bit(NFS_CS_REUSEPORT, &cl_init.init_flags);
 883	if (proto == XPRT_TRANSPORT_TCP)
 884		cl_init.nconnect = nconnect;
 885
 886	if (server->flags & NFS_MOUNT_NORESVPORT)
 887		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 888	if (server->options & NFS_OPTION_MIGRATION)
 889		__set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 890	if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
 891		__set_bit(NFS_CS_TSM_POSSIBLE, &cl_init.init_flags);
 892	server->port = rpc_get_port(addr);
 893
 894	/* Allocate or find a client reference we can use */
 895	clp = nfs_get_client(&cl_init);
 896	if (IS_ERR(clp))
 897		return PTR_ERR(clp);
 898
 899	if (server->nfs_client == clp) {
 900		nfs_put_client(clp);
 901		return -ELOOP;
 902	}
 903
 904	/*
 905	 * Query for the lease time on clientid setup or renewal
 906	 *
 907	 * Note that this will be set on nfs_clients that were created
 908	 * only for the DS role and did not set this bit, but now will
 909	 * serve a dual role.
 910	 */
 911	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 912
 913	server->nfs_client = clp;
 914	return 0;
 915}
 916
 917/*
 918 * Set up a pNFS Data Server client.
 919 *
 920 * Return any existing nfs_client that matches server address,port,version
 921 * and minorversion.
 922 *
 923 * For a new nfs_client, use a soft mount (default), a low retrans and a
 924 * low timeout interval so that if a connection is lost, we retry through
 925 * the MDS.
 926 */
 927struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
 928		const struct sockaddr *ds_addr, int ds_addrlen,
 929		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
 930		u32 minor_version)
 931{
 932	struct rpc_timeout ds_timeout;
 933	struct nfs_client *mds_clp = mds_srv->nfs_client;
 934	struct nfs_client_initdata cl_init = {
 935		.addr = ds_addr,
 936		.addrlen = ds_addrlen,
 937		.nodename = mds_clp->cl_rpcclient->cl_nodename,
 938		.ip_addr = mds_clp->cl_ipaddr,
 939		.nfs_mod = &nfs_v4,
 940		.proto = ds_proto,
 941		.minorversion = minor_version,
 942		.net = mds_clp->cl_net,
 943		.timeparms = &ds_timeout,
 944		.cred = mds_srv->cred,
 945	};
 946	char buf[INET6_ADDRSTRLEN + 1];
 947
 948	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
 949		return ERR_PTR(-EINVAL);
 950	cl_init.hostname = buf;
 951
 952	if (mds_clp->cl_nconnect > 1 && ds_proto == XPRT_TRANSPORT_TCP)
 953		cl_init.nconnect = mds_clp->cl_nconnect;
 954
 955	if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
 956		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 957
 958	/*
 959	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 960	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 961	 * (section 13.1 RFC 5661).
 962	 */
 963	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 964	return nfs_get_client(&cl_init);
 965}
 966EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
 967
 968/*
 969 * Session has been established, and the client marked ready.
 970 * Limit the mount rsize, wsize and dtsize using negotiated fore
 971 * channel attributes.
 972 */
 973static void nfs4_session_limit_rwsize(struct nfs_server *server)
 974{
 975#ifdef CONFIG_NFS_V4_1
 976	struct nfs4_session *sess;
 977	u32 server_resp_sz;
 978	u32 server_rqst_sz;
 979
 980	if (!nfs4_has_session(server->nfs_client))
 981		return;
 982	sess = server->nfs_client->cl_session;
 983	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
 984	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
 985
 986	if (server->dtsize > server_resp_sz)
 987		server->dtsize = server_resp_sz;
 988	if (server->rsize > server_resp_sz)
 989		server->rsize = server_resp_sz;
 990	if (server->wsize > server_rqst_sz)
 991		server->wsize = server_rqst_sz;
 992#endif /* CONFIG_NFS_V4_1 */
 993}
 994
 995/*
 996 * Limit xattr sizes using the channel attributes.
 997 */
 998static void nfs4_session_limit_xasize(struct nfs_server *server)
 999{
1000#ifdef CONFIG_NFS_V4_2
1001	struct nfs4_session *sess;
1002	u32 server_gxa_sz;
1003	u32 server_sxa_sz;
1004	u32 server_lxa_sz;
1005
1006	if (!nfs4_has_session(server->nfs_client))
1007		return;
1008
1009	sess = server->nfs_client->cl_session;
1010
1011	server_gxa_sz = sess->fc_attrs.max_resp_sz - nfs42_maxgetxattr_overhead;
1012	server_sxa_sz = sess->fc_attrs.max_rqst_sz - nfs42_maxsetxattr_overhead;
1013	server_lxa_sz = sess->fc_attrs.max_resp_sz -
1014	    nfs42_maxlistxattrs_overhead;
1015
1016	if (server->gxasize > server_gxa_sz)
1017		server->gxasize = server_gxa_sz;
1018	if (server->sxasize > server_sxa_sz)
1019		server->sxasize = server_sxa_sz;
1020	if (server->lxasize > server_lxa_sz)
1021		server->lxasize = server_lxa_sz;
1022#endif
1023}
1024
1025static int nfs4_server_common_setup(struct nfs_server *server,
1026		struct nfs_fh *mntfh, bool auth_probe)
1027{
1028	struct nfs_fattr *fattr;
1029	int error;
1030
1031	/* data servers support only a subset of NFSv4.1 */
1032	if (is_ds_only_client(server->nfs_client))
1033		return -EPROTONOSUPPORT;
1034
1035	fattr = nfs_alloc_fattr();
1036	if (fattr == NULL)
1037		return -ENOMEM;
1038
1039	/* We must ensure the session is initialised first */
1040	error = nfs4_init_session(server->nfs_client);
1041	if (error < 0)
1042		goto out;
1043
1044	/* Set the basic capabilities */
1045	server->caps |= server->nfs_client->cl_mvops->init_caps;
1046	if (server->flags & NFS_MOUNT_NORDIRPLUS)
1047			server->caps &= ~NFS_CAP_READDIRPLUS;
 
 
1048	/*
1049	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
1050	 * authentication.
1051	 */
1052	if (nfs4_disable_idmapping &&
1053			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
1054		server->caps |= NFS_CAP_UIDGID_NOMAP;
1055
1056
1057	/* Probe the root fh to retrieve its FSID and filehandle */
1058	error = nfs4_get_rootfh(server, mntfh, auth_probe);
1059	if (error < 0)
1060		goto out;
1061
1062	dprintk("Server FSID: %llx:%llx\n",
1063			(unsigned long long) server->fsid.major,
1064			(unsigned long long) server->fsid.minor);
1065	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1066
1067	error = nfs_probe_fsinfo(server, mntfh, fattr);
1068	if (error < 0)
1069		goto out;
1070
1071	nfs4_session_limit_rwsize(server);
1072	nfs4_session_limit_xasize(server);
1073
1074	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1075		server->namelen = NFS4_MAXNAMLEN;
1076
1077	nfs_server_insert_lists(server);
1078	server->mount_time = jiffies;
1079	server->destroy = nfs4_destroy_server;
1080out:
1081	nfs_free_fattr(fattr);
1082	return error;
1083}
1084
1085/*
1086 * Create a version 4 volume record
1087 */
1088static int nfs4_init_server(struct nfs_server *server, struct fs_context *fc)
1089{
1090	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1091	struct rpc_timeout timeparms;
1092	int error;
1093
1094	nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
1095				ctx->timeo, ctx->retrans);
1096
1097	/* Initialise the client representation from the mount data */
1098	server->flags = ctx->flags;
1099	server->options = ctx->options;
1100	server->auth_info = ctx->auth_info;
1101
1102	/* Use the first specified auth flavor. If this flavor isn't
1103	 * allowed by the server, use the SECINFO path to try the
1104	 * other specified flavors */
1105	if (ctx->auth_info.flavor_len >= 1)
1106		ctx->selected_flavor = ctx->auth_info.flavors[0];
1107	else
1108		ctx->selected_flavor = RPC_AUTH_UNIX;
1109
1110	/* Get a client record */
1111	error = nfs4_set_client(server,
1112				ctx->nfs_server.hostname,
1113				&ctx->nfs_server.address,
1114				ctx->nfs_server.addrlen,
1115				ctx->client_address,
1116				ctx->nfs_server.protocol,
1117				&timeparms,
1118				ctx->minorversion,
1119				ctx->nfs_server.nconnect,
1120				fc->net_ns);
1121	if (error < 0)
1122		return error;
1123
1124	if (ctx->rsize)
1125		server->rsize = nfs_block_size(ctx->rsize, NULL);
1126	if (ctx->wsize)
1127		server->wsize = nfs_block_size(ctx->wsize, NULL);
1128
1129	server->acregmin = ctx->acregmin * HZ;
1130	server->acregmax = ctx->acregmax * HZ;
1131	server->acdirmin = ctx->acdirmin * HZ;
1132	server->acdirmax = ctx->acdirmax * HZ;
1133	server->port     = ctx->nfs_server.port;
1134
1135	return nfs_init_server_rpcclient(server, &timeparms,
1136					 ctx->selected_flavor);
1137}
1138
1139/*
1140 * Create a version 4 volume record
1141 * - keyed on server and FSID
1142 */
1143struct nfs_server *nfs4_create_server(struct fs_context *fc)
1144{
1145	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1146	struct nfs_server *server;
1147	bool auth_probe;
1148	int error;
1149
1150	server = nfs_alloc_server();
1151	if (!server)
1152		return ERR_PTR(-ENOMEM);
1153
1154	server->cred = get_cred(current_cred());
1155
1156	auth_probe = ctx->auth_info.flavor_len < 1;
1157
1158	/* set up the general RPC client */
1159	error = nfs4_init_server(server, fc);
1160	if (error < 0)
1161		goto error;
1162
1163	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1164	if (error < 0)
1165		goto error;
1166
1167	return server;
1168
1169error:
1170	nfs_free_server(server);
1171	return ERR_PTR(error);
1172}
1173
1174/*
1175 * Create an NFS4 referral server record
1176 */
1177struct nfs_server *nfs4_create_referral_server(struct fs_context *fc)
1178{
1179	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1180	struct nfs_client *parent_client;
1181	struct nfs_server *server, *parent_server;
1182	bool auth_probe;
1183	int error;
1184
1185	server = nfs_alloc_server();
1186	if (!server)
1187		return ERR_PTR(-ENOMEM);
1188
1189	parent_server = NFS_SB(ctx->clone_data.sb);
1190	parent_client = parent_server->nfs_client;
1191
1192	server->cred = get_cred(parent_server->cred);
1193
1194	/* Initialise the client representation from the parent server */
1195	nfs_server_copy_userdata(server, parent_server);
1196
1197	/* Get a client representation */
1198#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1199	rpc_set_port(&ctx->nfs_server.address, NFS_RDMA_PORT);
1200	error = nfs4_set_client(server,
1201				ctx->nfs_server.hostname,
1202				&ctx->nfs_server.address,
1203				ctx->nfs_server.addrlen,
1204				parent_client->cl_ipaddr,
1205				XPRT_TRANSPORT_RDMA,
1206				parent_server->client->cl_timeout,
1207				parent_client->cl_mvops->minor_version,
1208				parent_client->cl_nconnect,
1209				parent_client->cl_net);
1210	if (!error)
1211		goto init_server;
1212#endif	/* IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA) */
1213
1214	rpc_set_port(&ctx->nfs_server.address, NFS_PORT);
1215	error = nfs4_set_client(server,
1216				ctx->nfs_server.hostname,
1217				&ctx->nfs_server.address,
1218				ctx->nfs_server.addrlen,
1219				parent_client->cl_ipaddr,
1220				XPRT_TRANSPORT_TCP,
1221				parent_server->client->cl_timeout,
1222				parent_client->cl_mvops->minor_version,
1223				parent_client->cl_nconnect,
1224				parent_client->cl_net);
1225	if (error < 0)
1226		goto error;
1227
1228#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1229init_server:
1230#endif
1231	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout,
1232					  ctx->selected_flavor);
1233	if (error < 0)
1234		goto error;
1235
1236	auth_probe = parent_server->auth_info.flavor_len < 1;
1237
1238	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1239	if (error < 0)
1240		goto error;
1241
1242	return server;
1243
1244error:
1245	nfs_free_server(server);
1246	return ERR_PTR(error);
1247}
1248
1249/*
1250 * Grab the destination's particulars, including lease expiry time.
1251 *
1252 * Returns zero if probe succeeded and retrieved FSID matches the FSID
1253 * we have cached.
1254 */
1255static int nfs_probe_destination(struct nfs_server *server)
1256{
1257	struct inode *inode = d_inode(server->super->s_root);
1258	struct nfs_fattr *fattr;
1259	int error;
1260
1261	fattr = nfs_alloc_fattr();
1262	if (fattr == NULL)
1263		return -ENOMEM;
1264
1265	/* Sanity: the probe won't work if the destination server
1266	 * does not recognize the migrated FH. */
1267	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1268
1269	nfs_free_fattr(fattr);
1270	return error;
1271}
1272
1273/**
1274 * nfs4_update_server - Move an nfs_server to a different nfs_client
1275 *
1276 * @server: represents FSID to be moved
1277 * @hostname: new end-point's hostname
1278 * @sap: new end-point's socket address
1279 * @salen: size of "sap"
1280 * @net: net namespace
1281 *
1282 * The nfs_server must be quiescent before this function is invoked.
1283 * Either its session is drained (NFSv4.1+), or its transport is
1284 * plugged and drained (NFSv4.0).
1285 *
1286 * Returns zero on success, or a negative errno value.
1287 */
1288int nfs4_update_server(struct nfs_server *server, const char *hostname,
1289		       struct sockaddr *sap, size_t salen, struct net *net)
1290{
1291	struct nfs_client *clp = server->nfs_client;
1292	struct rpc_clnt *clnt = server->client;
1293	struct xprt_create xargs = {
1294		.ident		= clp->cl_proto,
1295		.net		= net,
1296		.dstaddr	= sap,
1297		.addrlen	= salen,
1298		.servername	= hostname,
1299	};
1300	char buf[INET6_ADDRSTRLEN + 1];
1301	struct sockaddr_storage address;
1302	struct sockaddr *localaddr = (struct sockaddr *)&address;
1303	int error;
1304
1305	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1306	if (error != 0)
1307		return error;
1308
1309	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1310	if (error != 0)
1311		return error;
1312
1313	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
1314		return -EAFNOSUPPORT;
1315
1316	nfs_server_remove_lists(server);
1317	set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1318	error = nfs4_set_client(server, hostname, sap, salen, buf,
1319				clp->cl_proto, clnt->cl_timeout,
1320				clp->cl_minorversion,
1321				clp->cl_nconnect, net);
1322	clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1323	if (error != 0) {
1324		nfs_server_insert_lists(server);
1325		return error;
1326	}
1327	nfs_put_client(clp);
1328
1329	if (server->nfs_client->cl_hostname == NULL)
1330		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1331	nfs_server_insert_lists(server);
1332
1333	return nfs_probe_destination(server);
1334}
v5.14.15
   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
  22#define NFSDBG_FACILITY		NFSDBG_CLIENT
  23
  24/*
  25 * Get a unique NFSv4.0 callback identifier which will be used
  26 * by the V4.0 callback service to lookup the nfs_client struct
  27 */
  28static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
  29{
  30	int ret = 0;
  31	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  32
  33	if (clp->rpc_ops->version != 4 || minorversion != 0)
  34		return ret;
  35	idr_preload(GFP_KERNEL);
  36	spin_lock(&nn->nfs_client_lock);
  37	ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
  38	if (ret >= 0)
  39		clp->cl_cb_ident = ret;
  40	spin_unlock(&nn->nfs_client_lock);
  41	idr_preload_end();
  42	return ret < 0 ? ret : 0;
  43}
  44
  45#ifdef CONFIG_NFS_V4_1
  46/*
  47 * Per auth flavor data server rpc clients
  48 */
  49struct nfs4_ds_server {
  50	struct list_head	list;   /* ds_clp->cl_ds_clients */
  51	struct rpc_clnt		*rpc_clnt;
  52};
  53
  54/**
  55 * nfs4_find_ds_client - Common lookup case for DS I/O
  56 * @ds_clp: pointer to the DS's nfs_client
  57 * @flavor: rpc auth flavour to match
  58 */
  59static struct nfs4_ds_server *
  60nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  61{
  62	struct nfs4_ds_server *dss;
  63
  64	rcu_read_lock();
  65	list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
  66		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  67			continue;
  68		goto out;
  69	}
  70	dss = NULL;
  71out:
  72	rcu_read_unlock();
  73	return dss;
  74}
  75
  76static struct nfs4_ds_server *
  77nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
  78			   struct nfs4_ds_server *new)
  79{
  80	struct nfs4_ds_server *dss;
  81
  82	spin_lock(&ds_clp->cl_lock);
  83	list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
  84		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  85			continue;
  86		goto out;
  87	}
  88	if (new)
  89		list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
  90	dss = new;
  91out:
  92	spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
  93	return dss;
  94}
  95
  96static struct nfs4_ds_server *
  97nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  98{
  99	struct nfs4_ds_server *dss;
 100
 101	dss = kmalloc(sizeof(*dss), GFP_NOFS);
 102	if (dss == NULL)
 103		return ERR_PTR(-ENOMEM);
 104
 105	dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
 106	if (IS_ERR(dss->rpc_clnt)) {
 107		int err = PTR_ERR(dss->rpc_clnt);
 108		kfree (dss);
 109		return ERR_PTR(err);
 110	}
 111	INIT_LIST_HEAD(&dss->list);
 112
 113	return dss;
 114}
 115
 116static void
 117nfs4_free_ds_server(struct nfs4_ds_server *dss)
 118{
 119	rpc_release_client(dss->rpc_clnt);
 120	kfree(dss);
 121}
 122
 123/**
 124 * nfs4_find_or_create_ds_client - Find or create a DS rpc client
 125 * @ds_clp: pointer to the DS's nfs_client
 126 * @inode: pointer to the inode
 127 *
 128 * Find or create a DS rpc client with th MDS server rpc client auth flavor
 129 * in the nfs_client cl_ds_clients list.
 130 */
 131struct rpc_clnt *
 132nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
 133{
 134	struct nfs4_ds_server *dss, *new;
 135	rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
 136
 137	dss = nfs4_find_ds_client(ds_clp, flavor);
 138	if (dss != NULL)
 139		goto out;
 140	new = nfs4_alloc_ds_server(ds_clp, flavor);
 141	if (IS_ERR(new))
 142		return ERR_CAST(new);
 143	dss = nfs4_add_ds_client(ds_clp, flavor, new);
 144	if (dss != new)
 145		nfs4_free_ds_server(new);
 146out:
 147	return dss->rpc_clnt;
 148}
 149EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
 150
 151static void
 152nfs4_shutdown_ds_clients(struct nfs_client *clp)
 153{
 154	struct nfs4_ds_server *dss;
 155
 156	while (!list_empty(&clp->cl_ds_clients)) {
 157		dss = list_entry(clp->cl_ds_clients.next,
 158					struct nfs4_ds_server, list);
 159		list_del(&dss->list);
 160		rpc_shutdown_client(dss->rpc_clnt);
 161		kfree (dss);
 162	}
 163}
 164
 165static void
 166nfs4_cleanup_callback(struct nfs_client *clp)
 167{
 168	struct nfs4_copy_state *cp_state;
 169
 170	while (!list_empty(&clp->pending_cb_stateids)) {
 171		cp_state = list_entry(clp->pending_cb_stateids.next,
 172					struct nfs4_copy_state, copies);
 173		list_del(&cp_state->copies);
 174		kfree(cp_state);
 175	}
 176}
 177
 178void nfs41_shutdown_client(struct nfs_client *clp)
 179{
 180	if (nfs4_has_session(clp)) {
 181		nfs4_cleanup_callback(clp);
 182		nfs4_shutdown_ds_clients(clp);
 183		nfs4_destroy_session(clp->cl_session);
 184		nfs4_destroy_clientid(clp);
 185	}
 186
 187}
 188#endif	/* CONFIG_NFS_V4_1 */
 189
 190void nfs40_shutdown_client(struct nfs_client *clp)
 191{
 192	if (clp->cl_slot_tbl) {
 193		nfs4_shutdown_slot_table(clp->cl_slot_tbl);
 194		kfree(clp->cl_slot_tbl);
 195	}
 196}
 197
 198struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
 199{
 200	char buf[INET6_ADDRSTRLEN + 1];
 201	const char *ip_addr = cl_init->ip_addr;
 202	struct nfs_client *clp = nfs_alloc_client(cl_init);
 203	int err;
 204
 205	if (IS_ERR(clp))
 206		return clp;
 207
 208	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
 209	if (err)
 210		goto error;
 211
 212	if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
 213		err = -EINVAL;
 214		goto error;
 215	}
 216
 217	spin_lock_init(&clp->cl_lock);
 218	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
 219	INIT_LIST_HEAD(&clp->cl_ds_clients);
 220	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
 221	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 222	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 223	clp->cl_mig_gen = 1;
 224#if IS_ENABLED(CONFIG_NFS_V4_1)
 225	init_waitqueue_head(&clp->cl_lock_waitq);
 226#endif
 227	INIT_LIST_HEAD(&clp->pending_cb_stateids);
 228
 229	if (cl_init->minorversion != 0)
 230		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 231	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
 232	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 233
 234	/*
 235	 * Set up the connection to the server before we add add to the
 236	 * global list.
 237	 */
 238	err = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
 239	if (err == -EINVAL)
 240		err = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
 241	if (err < 0)
 242		goto error;
 243
 244	/* If no clientaddr= option was specified, find a usable cb address */
 245	if (ip_addr == NULL) {
 246		struct sockaddr_storage cb_addr;
 247		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
 248
 249		err = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
 250		if (err < 0)
 251			goto error;
 252		err = rpc_ntop(sap, buf, sizeof(buf));
 253		if (err < 0)
 254			goto error;
 255		ip_addr = (const char *)buf;
 256	}
 257	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 258
 259	err = nfs_idmap_new(clp);
 260	if (err < 0) {
 261		dprintk("%s: failed to create idmapper. Error = %d\n",
 262			__func__, err);
 263		goto error;
 264	}
 265	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 266	return clp;
 267
 268error:
 269	nfs_free_client(clp);
 270	return ERR_PTR(err);
 271}
 272
 273/*
 274 * Destroy the NFS4 callback service
 275 */
 276static void nfs4_destroy_callback(struct nfs_client *clp)
 277{
 278	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 279		nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 280}
 281
 282static void nfs4_shutdown_client(struct nfs_client *clp)
 283{
 284	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 285		nfs4_kill_renewd(clp);
 286	clp->cl_mvops->shutdown_client(clp);
 287	nfs4_destroy_callback(clp);
 288	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 289		nfs_idmap_delete(clp);
 290
 291	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 292	kfree(clp->cl_serverowner);
 293	kfree(clp->cl_serverscope);
 294	kfree(clp->cl_implid);
 295	kfree(clp->cl_owner_id);
 296}
 297
 298void nfs4_free_client(struct nfs_client *clp)
 299{
 300	nfs4_shutdown_client(clp);
 301	nfs_free_client(clp);
 302}
 303
 304/*
 305 * Initialize the NFS4 callback service
 306 */
 307static int nfs4_init_callback(struct nfs_client *clp)
 308{
 309	struct rpc_xprt *xprt;
 310	int error;
 311
 312	xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
 313
 314	if (nfs4_has_session(clp)) {
 315		error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
 316		if (error < 0)
 317			return error;
 318	}
 319
 320	error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
 321	if (error < 0) {
 322		dprintk("%s: failed to start callback. Error = %d\n",
 323			__func__, error);
 324		return error;
 325	}
 326	__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 327
 328	return 0;
 329}
 330
 331/**
 332 * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
 333 * @clp: nfs_client to initialize
 334 *
 335 * Returns zero on success, or a negative errno if some error occurred.
 336 */
 337int nfs40_init_client(struct nfs_client *clp)
 338{
 339	struct nfs4_slot_table *tbl;
 340	int ret;
 341
 342	tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
 343	if (tbl == NULL)
 344		return -ENOMEM;
 345
 346	ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
 347					"NFSv4.0 transport Slot table");
 348	if (ret) {
 349		kfree(tbl);
 350		return ret;
 351	}
 352
 353	clp->cl_slot_tbl = tbl;
 354	return 0;
 355}
 356
 357#if defined(CONFIG_NFS_V4_1)
 358
 359/**
 360 * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 361 * @clp: nfs_client to initialize
 362 *
 363 * Returns zero on success, or a negative errno if some error occurred.
 364 */
 365int nfs41_init_client(struct nfs_client *clp)
 366{
 367	struct nfs4_session *session = NULL;
 368
 369	/*
 370	 * Create the session and mark it expired.
 371	 * When a SEQUENCE operation encounters the expired session
 372	 * it will do session recovery to initialize it.
 373	 */
 374	session = nfs4_alloc_session(clp);
 375	if (!session)
 376		return -ENOMEM;
 377
 378	clp->cl_session = session;
 379
 380	/*
 381	 * The create session reply races with the server back
 382	 * channel probe. Mark the client NFS_CS_SESSION_INITING
 383	 * so that the client back channel can find the
 384	 * nfs_client struct
 385	 */
 386	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 387	return 0;
 388}
 389
 390#endif	/* CONFIG_NFS_V4_1 */
 391
 392/*
 393 * Initialize the minor version specific parts of an NFS4 client record
 394 */
 395static int nfs4_init_client_minor_version(struct nfs_client *clp)
 396{
 397	int ret;
 398
 399	ret = clp->cl_mvops->init_client(clp);
 400	if (ret)
 401		return ret;
 402	return nfs4_init_callback(clp);
 403}
 404
 405/**
 406 * nfs4_init_client - Initialise an NFS4 client record
 407 *
 408 * @clp: nfs_client to initialise
 409 * @cl_init: pointer to nfs_client_initdata
 410 *
 411 * Returns pointer to an NFS client, or an ERR_PTR value.
 412 */
 413struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 414				    const struct nfs_client_initdata *cl_init)
 415{
 
 
 416	struct nfs_client *old;
 417	int error;
 418
 419	if (clp->cl_cons_state == NFS_CS_READY)
 420		/* the client is initialised already */
 421		return clp;
 422
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 423	error = nfs4_init_client_minor_version(clp);
 424	if (error < 0)
 425		goto error;
 426
 427	error = nfs4_discover_server_trunking(clp, &old);
 428	if (error < 0)
 429		goto error;
 430
 431	if (clp != old) {
 432		clp->cl_preserve_clid = true;
 433		/*
 434		 * Mark the client as having failed initialization so other
 435		 * processes walking the nfs_client_list in nfs_match_client()
 436		 * won't try to use it.
 437		 */
 438		nfs_mark_client_ready(clp, -EPERM);
 439	}
 
 440	clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
 441	nfs_put_client(clp);
 442	return old;
 443
 444error:
 445	nfs_mark_client_ready(clp, error);
 446	nfs_put_client(clp);
 447	return ERR_PTR(error);
 448}
 449
 450/*
 451 * SETCLIENTID just did a callback update with the callback ident in
 452 * "drop," but server trunking discovery claims "drop" and "keep" are
 453 * actually the same server.  Swap the callback IDs so that "keep"
 454 * will continue to use the callback ident the server now knows about,
 455 * and so that "keep"'s original callback ident is destroyed when
 456 * "drop" is freed.
 457 */
 458static void nfs4_swap_callback_idents(struct nfs_client *keep,
 459				      struct nfs_client *drop)
 460{
 461	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
 462	unsigned int save = keep->cl_cb_ident;
 463
 464	if (keep->cl_cb_ident == drop->cl_cb_ident)
 465		return;
 466
 467	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
 468		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
 469
 470	spin_lock(&nn->nfs_client_lock);
 471
 472	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
 473	keep->cl_cb_ident = drop->cl_cb_ident;
 474
 475	idr_replace(&nn->cb_ident_idr, drop, save);
 476	drop->cl_cb_ident = save;
 477
 478	spin_unlock(&nn->nfs_client_lock);
 479}
 480
 481static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
 482		const struct nfs_client *clp2)
 483{
 484	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
 485		return true;
 486	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
 487}
 488
 489static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
 490{
 491	return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
 492}
 493
 494static int nfs4_match_client(struct nfs_client  *pos,  struct nfs_client *new,
 495			     struct nfs_client **prev, struct nfs_net *nn)
 496{
 497	int status;
 498
 499	if (pos->rpc_ops != new->rpc_ops)
 500		return 1;
 501
 502	if (pos->cl_minorversion != new->cl_minorversion)
 503		return 1;
 504
 505	/* If "pos" isn't marked ready, we can't trust the
 506	 * remaining fields in "pos", especially the client
 507	 * ID and serverowner fields.  Wait for CREATE_SESSION
 508	 * to finish. */
 509	if (pos->cl_cons_state > NFS_CS_READY) {
 510		refcount_inc(&pos->cl_count);
 511		spin_unlock(&nn->nfs_client_lock);
 512
 513		nfs_put_client(*prev);
 514		*prev = pos;
 515
 516		status = nfs_wait_client_init_complete(pos);
 517		spin_lock(&nn->nfs_client_lock);
 518
 519		if (status < 0)
 520			return status;
 521	}
 522
 523	if (pos->cl_cons_state != NFS_CS_READY)
 524		return 1;
 525
 526	if (pos->cl_clientid != new->cl_clientid)
 527		return 1;
 528
 529	/* NFSv4.1 always uses the uniform string, however someone
 530	 * might switch the uniquifier string on us.
 531	 */
 532	if (!nfs4_match_client_owner_id(pos, new))
 533		return 1;
 534
 535	return 0;
 536}
 537
 538/**
 539 * nfs40_walk_client_list - Find server that recognizes a client ID
 540 *
 541 * @new: nfs_client with client ID to test
 542 * @result: OUT: found nfs_client, or new
 543 * @cred: credential to use for trunking test
 544 *
 545 * Returns zero, a negative errno, or a negative NFS4ERR status.
 546 * If zero is returned, an nfs_client pointer is planted in "result."
 547 *
 548 * NB: nfs40_walk_client_list() relies on the new nfs_client being
 549 *     the last nfs_client on the list.
 550 */
 551int nfs40_walk_client_list(struct nfs_client *new,
 552			   struct nfs_client **result,
 553			   const struct cred *cred)
 554{
 555	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 556	struct nfs_client *pos, *prev = NULL;
 557	struct nfs4_setclientid_res clid = {
 558		.clientid	= new->cl_clientid,
 559		.confirm	= new->cl_confirm,
 560	};
 561	int status = -NFS4ERR_STALE_CLIENTID;
 562
 563	spin_lock(&nn->nfs_client_lock);
 564	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 565
 566		if (pos == new)
 567			goto found;
 568
 569		status = nfs4_match_client(pos, new, &prev, nn);
 570		if (status < 0)
 571			goto out_unlock;
 572		if (status != 0)
 573			continue;
 574		/*
 575		 * We just sent a new SETCLIENTID, which should have
 576		 * caused the server to return a new cl_confirm.  So if
 577		 * cl_confirm is the same, then this is a different
 578		 * server that just returned the same cl_confirm by
 579		 * coincidence:
 580		 */
 581		if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
 582						       &new->cl_confirm))
 583			continue;
 584		/*
 585		 * But if the cl_confirm's are different, then the only
 586		 * way that a SETCLIENTID_CONFIRM to pos can succeed is
 587		 * if new and pos point to the same server:
 588		 */
 589found:
 590		refcount_inc(&pos->cl_count);
 591		spin_unlock(&nn->nfs_client_lock);
 592
 593		nfs_put_client(prev);
 594		prev = pos;
 595
 596		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 597		switch (status) {
 598		case -NFS4ERR_STALE_CLIENTID:
 599			break;
 600		case 0:
 601			nfs4_swap_callback_idents(pos, new);
 602			pos->cl_confirm = new->cl_confirm;
 603			nfs_mark_client_ready(pos, NFS_CS_READY);
 604
 605			prev = NULL;
 606			*result = pos;
 607			goto out;
 608		case -ERESTARTSYS:
 609		case -ETIMEDOUT:
 610			/* The callback path may have been inadvertently
 611			 * changed. Schedule recovery!
 612			 */
 613			nfs4_schedule_path_down_recovery(pos);
 614			goto out;
 615		default:
 616			goto out;
 617		}
 618
 619		spin_lock(&nn->nfs_client_lock);
 620	}
 621out_unlock:
 622	spin_unlock(&nn->nfs_client_lock);
 623
 624	/* No match found. The server lost our clientid */
 625out:
 626	nfs_put_client(prev);
 627	return status;
 628}
 629
 630#ifdef CONFIG_NFS_V4_1
 631/*
 632 * Returns true if the server major ids match
 633 */
 634bool
 635nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
 636				struct nfs41_server_owner *o2)
 637{
 638	if (o1->major_id_sz != o2->major_id_sz)
 639		return false;
 640	return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
 641}
 642
 643/*
 644 * Returns true if the server scopes match
 645 */
 646static bool
 647nfs4_check_server_scope(struct nfs41_server_scope *s1,
 648			struct nfs41_server_scope *s2)
 649{
 650	if (s1->server_scope_sz != s2->server_scope_sz)
 651		return false;
 652	return memcmp(s1->server_scope, s2->server_scope,
 653					s1->server_scope_sz) == 0;
 654}
 655
 656/**
 657 * nfs4_detect_session_trunking - Checks for session trunking.
 658 * @clp:    original mount nfs_client
 659 * @res:    result structure from an exchange_id using the original mount
 660 *          nfs_client with a new multi_addr transport
 661 * @xprt:   pointer to the transport to add.
 662 *
 663 * Called after a successful EXCHANGE_ID on a multi-addr connection.
 664 * Upon success, add the transport.
 665 *
 666 * Returns zero on success, otherwise -EINVAL
 667 *
 668 * Note: since the exchange_id for the new multi_addr transport uses the
 669 * same nfs_client from the original mount, the cl_owner_id is reused,
 670 * so eir_clientowner is the same.
 671 */
 672int nfs4_detect_session_trunking(struct nfs_client *clp,
 673				 struct nfs41_exchange_id_res *res,
 674				 struct rpc_xprt *xprt)
 675{
 676	/* Check eir_clientid */
 677	if (clp->cl_clientid != res->clientid)
 678		goto out_err;
 679
 680	/* Check eir_server_owner so_major_id */
 681	if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
 682					     res->server_owner))
 683		goto out_err;
 684
 685	/* Check eir_server_owner so_minor_id */
 686	if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
 687		goto out_err;
 688
 689	/* Check eir_server_scope */
 690	if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
 691		goto out_err;
 692
 693	pr_info("NFS:  %s: Session trunking succeeded for %s\n",
 694		clp->cl_hostname,
 695		xprt->address_strings[RPC_DISPLAY_ADDR]);
 696
 697	return 0;
 698out_err:
 699	pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
 700		xprt->address_strings[RPC_DISPLAY_ADDR]);
 701
 702	return -EINVAL;
 703}
 704
 705/**
 706 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 707 *
 708 * @new: nfs_client with client ID to test
 709 * @result: OUT: found nfs_client, or new
 710 * @cred: credential to use for trunking test
 711 *
 712 * Returns zero, a negative errno, or a negative NFS4ERR status.
 713 * If zero is returned, an nfs_client pointer is planted in "result."
 714 *
 715 * NB: nfs41_walk_client_list() relies on the new nfs_client being
 716 *     the last nfs_client on the list.
 717 */
 718int nfs41_walk_client_list(struct nfs_client *new,
 719			   struct nfs_client **result,
 720			   const struct cred *cred)
 721{
 722	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 723	struct nfs_client *pos, *prev = NULL;
 724	int status = -NFS4ERR_STALE_CLIENTID;
 725
 726	spin_lock(&nn->nfs_client_lock);
 727	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 728
 729		if (pos == new)
 730			goto found;
 731
 732		status = nfs4_match_client(pos, new, &prev, nn);
 733		if (status < 0)
 734			goto out;
 735		if (status != 0)
 736			continue;
 737
 738		/*
 739		 * Note that session trunking is just a special subcase of
 740		 * client id trunking. In either case, we want to fall back
 741		 * to using the existing nfs_client.
 742		 */
 743		if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
 744						     new->cl_serverowner))
 745			continue;
 746
 747found:
 748		refcount_inc(&pos->cl_count);
 749		*result = pos;
 750		status = 0;
 751		break;
 752	}
 753
 754out:
 755	spin_unlock(&nn->nfs_client_lock);
 756	nfs_put_client(prev);
 757	return status;
 758}
 759#endif	/* CONFIG_NFS_V4_1 */
 760
 761static void nfs4_destroy_server(struct nfs_server *server)
 762{
 763	LIST_HEAD(freeme);
 764
 765	nfs_server_return_all_delegations(server);
 766	unset_pnfs_layoutdriver(server);
 767	nfs4_purge_state_owners(server, &freeme);
 768	nfs4_free_state_owners(&freeme);
 769}
 770
 771/*
 772 * NFSv4.0 callback thread helper
 773 *
 774 * Find a client by callback identifier
 775 */
 776struct nfs_client *
 777nfs4_find_client_ident(struct net *net, int cb_ident)
 778{
 779	struct nfs_client *clp;
 780	struct nfs_net *nn = net_generic(net, nfs_net_id);
 781
 782	spin_lock(&nn->nfs_client_lock);
 783	clp = idr_find(&nn->cb_ident_idr, cb_ident);
 784	if (clp)
 785		refcount_inc(&clp->cl_count);
 786	spin_unlock(&nn->nfs_client_lock);
 787	return clp;
 788}
 789
 790#if defined(CONFIG_NFS_V4_1)
 791/* Common match routine for v4.0 and v4.1 callback services */
 792static bool nfs4_cb_match_client(const struct sockaddr *addr,
 793		struct nfs_client *clp, u32 minorversion)
 794{
 795	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 796
 797	/* Don't match clients that failed to initialise */
 798	if (!(clp->cl_cons_state == NFS_CS_READY ||
 799	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
 800		return false;
 801
 802	smp_rmb();
 803
 804	/* Match the version and minorversion */
 805	if (clp->rpc_ops->version != 4 ||
 806	    clp->cl_minorversion != minorversion)
 807		return false;
 808
 809	/* Match only the IP address, not the port number */
 810	return rpc_cmp_addr(addr, clap);
 811}
 812
 813/*
 814 * NFSv4.1 callback thread helper
 815 * For CB_COMPOUND calls, find a client by IP address, protocol version,
 816 * minorversion, and sessionID
 817 *
 818 * Returns NULL if no such client
 819 */
 820struct nfs_client *
 821nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 822			   struct nfs4_sessionid *sid, u32 minorversion)
 823{
 824	struct nfs_client *clp;
 825	struct nfs_net *nn = net_generic(net, nfs_net_id);
 826
 827	spin_lock(&nn->nfs_client_lock);
 828	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 829		if (!nfs4_cb_match_client(addr, clp, minorversion))
 830			continue;
 831
 832		if (!nfs4_has_session(clp))
 833			continue;
 834
 835		/* Match sessionid*/
 836		if (memcmp(clp->cl_session->sess_id.data,
 837		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 838			continue;
 839
 840		refcount_inc(&clp->cl_count);
 841		spin_unlock(&nn->nfs_client_lock);
 842		return clp;
 843	}
 844	spin_unlock(&nn->nfs_client_lock);
 845	return NULL;
 846}
 847
 848#else /* CONFIG_NFS_V4_1 */
 849
 850struct nfs_client *
 851nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 852			   struct nfs4_sessionid *sid, u32 minorversion)
 853{
 854	return NULL;
 855}
 856#endif /* CONFIG_NFS_V4_1 */
 857
 858/*
 859 * Set up an NFS4 client
 860 */
 861static int nfs4_set_client(struct nfs_server *server,
 862		const char *hostname,
 863		const struct sockaddr *addr,
 864		const size_t addrlen,
 865		const char *ip_addr,
 866		int proto, const struct rpc_timeout *timeparms,
 867		u32 minorversion, unsigned int nconnect,
 868		struct net *net)
 869{
 870	struct nfs_client_initdata cl_init = {
 871		.hostname = hostname,
 872		.addr = addr,
 873		.addrlen = addrlen,
 874		.ip_addr = ip_addr,
 875		.nfs_mod = &nfs_v4,
 876		.proto = proto,
 877		.minorversion = minorversion,
 878		.net = net,
 879		.timeparms = timeparms,
 880		.cred = server->cred,
 881	};
 882	struct nfs_client *clp;
 883
 884	if (minorversion == 0)
 885		__set_bit(NFS_CS_REUSEPORT, &cl_init.init_flags);
 886	if (proto == XPRT_TRANSPORT_TCP)
 887		cl_init.nconnect = nconnect;
 888
 889	if (server->flags & NFS_MOUNT_NORESVPORT)
 890		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 891	if (server->options & NFS_OPTION_MIGRATION)
 892		__set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 893	if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
 894		__set_bit(NFS_CS_TSM_POSSIBLE, &cl_init.init_flags);
 895	server->port = rpc_get_port(addr);
 896
 897	/* Allocate or find a client reference we can use */
 898	clp = nfs_get_client(&cl_init);
 899	if (IS_ERR(clp))
 900		return PTR_ERR(clp);
 901
 902	if (server->nfs_client == clp) {
 903		nfs_put_client(clp);
 904		return -ELOOP;
 905	}
 906
 907	/*
 908	 * Query for the lease time on clientid setup or renewal
 909	 *
 910	 * Note that this will be set on nfs_clients that were created
 911	 * only for the DS role and did not set this bit, but now will
 912	 * serve a dual role.
 913	 */
 914	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 915
 916	server->nfs_client = clp;
 917	return 0;
 918}
 919
 920/*
 921 * Set up a pNFS Data Server client.
 922 *
 923 * Return any existing nfs_client that matches server address,port,version
 924 * and minorversion.
 925 *
 926 * For a new nfs_client, use a soft mount (default), a low retrans and a
 927 * low timeout interval so that if a connection is lost, we retry through
 928 * the MDS.
 929 */
 930struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
 931		const struct sockaddr *ds_addr, int ds_addrlen,
 932		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
 933		u32 minor_version)
 934{
 935	struct rpc_timeout ds_timeout;
 936	struct nfs_client *mds_clp = mds_srv->nfs_client;
 937	struct nfs_client_initdata cl_init = {
 938		.addr = ds_addr,
 939		.addrlen = ds_addrlen,
 940		.nodename = mds_clp->cl_rpcclient->cl_nodename,
 941		.ip_addr = mds_clp->cl_ipaddr,
 942		.nfs_mod = &nfs_v4,
 943		.proto = ds_proto,
 944		.minorversion = minor_version,
 945		.net = mds_clp->cl_net,
 946		.timeparms = &ds_timeout,
 947		.cred = mds_srv->cred,
 948	};
 949	char buf[INET6_ADDRSTRLEN + 1];
 950
 951	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
 952		return ERR_PTR(-EINVAL);
 953	cl_init.hostname = buf;
 954
 955	if (mds_clp->cl_nconnect > 1 && ds_proto == XPRT_TRANSPORT_TCP)
 956		cl_init.nconnect = mds_clp->cl_nconnect;
 957
 958	if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
 959		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 960
 961	/*
 962	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 963	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 964	 * (section 13.1 RFC 5661).
 965	 */
 966	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 967	return nfs_get_client(&cl_init);
 968}
 969EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
 970
 971/*
 972 * Session has been established, and the client marked ready.
 973 * Limit the mount rsize, wsize and dtsize using negotiated fore
 974 * channel attributes.
 975 */
 976static void nfs4_session_limit_rwsize(struct nfs_server *server)
 977{
 978#ifdef CONFIG_NFS_V4_1
 979	struct nfs4_session *sess;
 980	u32 server_resp_sz;
 981	u32 server_rqst_sz;
 982
 983	if (!nfs4_has_session(server->nfs_client))
 984		return;
 985	sess = server->nfs_client->cl_session;
 986	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
 987	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
 988
 989	if (server->dtsize > server_resp_sz)
 990		server->dtsize = server_resp_sz;
 991	if (server->rsize > server_resp_sz)
 992		server->rsize = server_resp_sz;
 993	if (server->wsize > server_rqst_sz)
 994		server->wsize = server_rqst_sz;
 995#endif /* CONFIG_NFS_V4_1 */
 996}
 997
 998/*
 999 * Limit xattr sizes using the channel attributes.
1000 */
1001static void nfs4_session_limit_xasize(struct nfs_server *server)
1002{
1003#ifdef CONFIG_NFS_V4_2
1004	struct nfs4_session *sess;
1005	u32 server_gxa_sz;
1006	u32 server_sxa_sz;
1007	u32 server_lxa_sz;
1008
1009	if (!nfs4_has_session(server->nfs_client))
1010		return;
1011
1012	sess = server->nfs_client->cl_session;
1013
1014	server_gxa_sz = sess->fc_attrs.max_resp_sz - nfs42_maxgetxattr_overhead;
1015	server_sxa_sz = sess->fc_attrs.max_rqst_sz - nfs42_maxsetxattr_overhead;
1016	server_lxa_sz = sess->fc_attrs.max_resp_sz -
1017	    nfs42_maxlistxattrs_overhead;
1018
1019	if (server->gxasize > server_gxa_sz)
1020		server->gxasize = server_gxa_sz;
1021	if (server->sxasize > server_sxa_sz)
1022		server->sxasize = server_sxa_sz;
1023	if (server->lxasize > server_lxa_sz)
1024		server->lxasize = server_lxa_sz;
1025#endif
1026}
1027
1028static int nfs4_server_common_setup(struct nfs_server *server,
1029		struct nfs_fh *mntfh, bool auth_probe)
1030{
1031	struct nfs_fattr *fattr;
1032	int error;
1033
1034	/* data servers support only a subset of NFSv4.1 */
1035	if (is_ds_only_client(server->nfs_client))
1036		return -EPROTONOSUPPORT;
1037
1038	fattr = nfs_alloc_fattr();
1039	if (fattr == NULL)
1040		return -ENOMEM;
1041
1042	/* We must ensure the session is initialised first */
1043	error = nfs4_init_session(server->nfs_client);
1044	if (error < 0)
1045		goto out;
1046
1047	/* Set the basic capabilities */
1048	server->caps |= server->nfs_client->cl_mvops->init_caps;
1049	if (server->flags & NFS_MOUNT_NORDIRPLUS)
1050			server->caps &= ~NFS_CAP_READDIRPLUS;
1051	if (server->nfs_client->cl_proto == XPRT_TRANSPORT_RDMA)
1052		server->caps &= ~NFS_CAP_READ_PLUS;
1053	/*
1054	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
1055	 * authentication.
1056	 */
1057	if (nfs4_disable_idmapping &&
1058			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
1059		server->caps |= NFS_CAP_UIDGID_NOMAP;
1060
1061
1062	/* Probe the root fh to retrieve its FSID and filehandle */
1063	error = nfs4_get_rootfh(server, mntfh, auth_probe);
1064	if (error < 0)
1065		goto out;
1066
1067	dprintk("Server FSID: %llx:%llx\n",
1068			(unsigned long long) server->fsid.major,
1069			(unsigned long long) server->fsid.minor);
1070	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1071
1072	error = nfs_probe_fsinfo(server, mntfh, fattr);
1073	if (error < 0)
1074		goto out;
1075
1076	nfs4_session_limit_rwsize(server);
1077	nfs4_session_limit_xasize(server);
1078
1079	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1080		server->namelen = NFS4_MAXNAMLEN;
1081
1082	nfs_server_insert_lists(server);
1083	server->mount_time = jiffies;
1084	server->destroy = nfs4_destroy_server;
1085out:
1086	nfs_free_fattr(fattr);
1087	return error;
1088}
1089
1090/*
1091 * Create a version 4 volume record
1092 */
1093static int nfs4_init_server(struct nfs_server *server, struct fs_context *fc)
1094{
1095	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1096	struct rpc_timeout timeparms;
1097	int error;
1098
1099	nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
1100				ctx->timeo, ctx->retrans);
1101
1102	/* Initialise the client representation from the mount data */
1103	server->flags = ctx->flags;
1104	server->options = ctx->options;
1105	server->auth_info = ctx->auth_info;
1106
1107	/* Use the first specified auth flavor. If this flavor isn't
1108	 * allowed by the server, use the SECINFO path to try the
1109	 * other specified flavors */
1110	if (ctx->auth_info.flavor_len >= 1)
1111		ctx->selected_flavor = ctx->auth_info.flavors[0];
1112	else
1113		ctx->selected_flavor = RPC_AUTH_UNIX;
1114
1115	/* Get a client record */
1116	error = nfs4_set_client(server,
1117				ctx->nfs_server.hostname,
1118				&ctx->nfs_server.address,
1119				ctx->nfs_server.addrlen,
1120				ctx->client_address,
1121				ctx->nfs_server.protocol,
1122				&timeparms,
1123				ctx->minorversion,
1124				ctx->nfs_server.nconnect,
1125				fc->net_ns);
1126	if (error < 0)
1127		return error;
1128
1129	if (ctx->rsize)
1130		server->rsize = nfs_block_size(ctx->rsize, NULL);
1131	if (ctx->wsize)
1132		server->wsize = nfs_block_size(ctx->wsize, NULL);
1133
1134	server->acregmin = ctx->acregmin * HZ;
1135	server->acregmax = ctx->acregmax * HZ;
1136	server->acdirmin = ctx->acdirmin * HZ;
1137	server->acdirmax = ctx->acdirmax * HZ;
1138	server->port     = ctx->nfs_server.port;
1139
1140	return nfs_init_server_rpcclient(server, &timeparms,
1141					 ctx->selected_flavor);
1142}
1143
1144/*
1145 * Create a version 4 volume record
1146 * - keyed on server and FSID
1147 */
1148struct nfs_server *nfs4_create_server(struct fs_context *fc)
1149{
1150	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1151	struct nfs_server *server;
1152	bool auth_probe;
1153	int error;
1154
1155	server = nfs_alloc_server();
1156	if (!server)
1157		return ERR_PTR(-ENOMEM);
1158
1159	server->cred = get_cred(fc->cred);
1160
1161	auth_probe = ctx->auth_info.flavor_len < 1;
1162
1163	/* set up the general RPC client */
1164	error = nfs4_init_server(server, fc);
1165	if (error < 0)
1166		goto error;
1167
1168	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1169	if (error < 0)
1170		goto error;
1171
1172	return server;
1173
1174error:
1175	nfs_free_server(server);
1176	return ERR_PTR(error);
1177}
1178
1179/*
1180 * Create an NFS4 referral server record
1181 */
1182struct nfs_server *nfs4_create_referral_server(struct fs_context *fc)
1183{
1184	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1185	struct nfs_client *parent_client;
1186	struct nfs_server *server, *parent_server;
1187	bool auth_probe;
1188	int error;
1189
1190	server = nfs_alloc_server();
1191	if (!server)
1192		return ERR_PTR(-ENOMEM);
1193
1194	parent_server = NFS_SB(ctx->clone_data.sb);
1195	parent_client = parent_server->nfs_client;
1196
1197	server->cred = get_cred(parent_server->cred);
1198
1199	/* Initialise the client representation from the parent server */
1200	nfs_server_copy_userdata(server, parent_server);
1201
1202	/* Get a client representation */
1203#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1204	rpc_set_port(&ctx->nfs_server.address, NFS_RDMA_PORT);
1205	error = nfs4_set_client(server,
1206				ctx->nfs_server.hostname,
1207				&ctx->nfs_server.address,
1208				ctx->nfs_server.addrlen,
1209				parent_client->cl_ipaddr,
1210				XPRT_TRANSPORT_RDMA,
1211				parent_server->client->cl_timeout,
1212				parent_client->cl_mvops->minor_version,
1213				parent_client->cl_nconnect,
1214				parent_client->cl_net);
1215	if (!error)
1216		goto init_server;
1217#endif	/* IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA) */
1218
1219	rpc_set_port(&ctx->nfs_server.address, NFS_PORT);
1220	error = nfs4_set_client(server,
1221				ctx->nfs_server.hostname,
1222				&ctx->nfs_server.address,
1223				ctx->nfs_server.addrlen,
1224				parent_client->cl_ipaddr,
1225				XPRT_TRANSPORT_TCP,
1226				parent_server->client->cl_timeout,
1227				parent_client->cl_mvops->minor_version,
1228				parent_client->cl_nconnect,
1229				parent_client->cl_net);
1230	if (error < 0)
1231		goto error;
1232
1233#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1234init_server:
1235#endif
1236	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout,
1237					  ctx->selected_flavor);
1238	if (error < 0)
1239		goto error;
1240
1241	auth_probe = parent_server->auth_info.flavor_len < 1;
1242
1243	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1244	if (error < 0)
1245		goto error;
1246
1247	return server;
1248
1249error:
1250	nfs_free_server(server);
1251	return ERR_PTR(error);
1252}
1253
1254/*
1255 * Grab the destination's particulars, including lease expiry time.
1256 *
1257 * Returns zero if probe succeeded and retrieved FSID matches the FSID
1258 * we have cached.
1259 */
1260static int nfs_probe_destination(struct nfs_server *server)
1261{
1262	struct inode *inode = d_inode(server->super->s_root);
1263	struct nfs_fattr *fattr;
1264	int error;
1265
1266	fattr = nfs_alloc_fattr();
1267	if (fattr == NULL)
1268		return -ENOMEM;
1269
1270	/* Sanity: the probe won't work if the destination server
1271	 * does not recognize the migrated FH. */
1272	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1273
1274	nfs_free_fattr(fattr);
1275	return error;
1276}
1277
1278/**
1279 * nfs4_update_server - Move an nfs_server to a different nfs_client
1280 *
1281 * @server: represents FSID to be moved
1282 * @hostname: new end-point's hostname
1283 * @sap: new end-point's socket address
1284 * @salen: size of "sap"
1285 * @net: net namespace
1286 *
1287 * The nfs_server must be quiescent before this function is invoked.
1288 * Either its session is drained (NFSv4.1+), or its transport is
1289 * plugged and drained (NFSv4.0).
1290 *
1291 * Returns zero on success, or a negative errno value.
1292 */
1293int nfs4_update_server(struct nfs_server *server, const char *hostname,
1294		       struct sockaddr *sap, size_t salen, struct net *net)
1295{
1296	struct nfs_client *clp = server->nfs_client;
1297	struct rpc_clnt *clnt = server->client;
1298	struct xprt_create xargs = {
1299		.ident		= clp->cl_proto,
1300		.net		= net,
1301		.dstaddr	= sap,
1302		.addrlen	= salen,
1303		.servername	= hostname,
1304	};
1305	char buf[INET6_ADDRSTRLEN + 1];
1306	struct sockaddr_storage address;
1307	struct sockaddr *localaddr = (struct sockaddr *)&address;
1308	int error;
1309
1310	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1311	if (error != 0)
1312		return error;
1313
1314	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1315	if (error != 0)
1316		return error;
1317
1318	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
1319		return -EAFNOSUPPORT;
1320
1321	nfs_server_remove_lists(server);
1322	set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1323	error = nfs4_set_client(server, hostname, sap, salen, buf,
1324				clp->cl_proto, clnt->cl_timeout,
1325				clp->cl_minorversion,
1326				clp->cl_nconnect, net);
1327	clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1328	if (error != 0) {
1329		nfs_server_insert_lists(server);
1330		return error;
1331	}
1332	nfs_put_client(clp);
1333
1334	if (server->nfs_client->cl_hostname == NULL)
1335		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1336	nfs_server_insert_lists(server);
1337
1338	return nfs_probe_destination(server);
1339}