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v6.2
   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	strscpy(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		nfs4_shutdown_slot_table(tbl);
 350		kfree(tbl);
 351		return ret;
 352	}
 353
 354	clp->cl_slot_tbl = tbl;
 355	return 0;
 356}
 357
 358#if defined(CONFIG_NFS_V4_1)
 359
 360/**
 361 * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 362 * @clp: nfs_client to initialize
 363 *
 364 * Returns zero on success, or a negative errno if some error occurred.
 365 */
 366int nfs41_init_client(struct nfs_client *clp)
 367{
 368	struct nfs4_session *session = NULL;
 369
 370	/*
 371	 * Create the session and mark it expired.
 372	 * When a SEQUENCE operation encounters the expired session
 373	 * it will do session recovery to initialize it.
 374	 */
 375	session = nfs4_alloc_session(clp);
 376	if (!session)
 377		return -ENOMEM;
 378
 379	clp->cl_session = session;
 380
 381	/*
 382	 * The create session reply races with the server back
 383	 * channel probe. Mark the client NFS_CS_SESSION_INITING
 384	 * so that the client back channel can find the
 385	 * nfs_client struct
 386	 */
 387	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 388	return 0;
 389}
 390
 391#endif	/* CONFIG_NFS_V4_1 */
 392
 393/*
 394 * Initialize the minor version specific parts of an NFS4 client record
 395 */
 396static int nfs4_init_client_minor_version(struct nfs_client *clp)
 397{
 398	int ret;
 399
 400	ret = clp->cl_mvops->init_client(clp);
 401	if (ret)
 402		return ret;
 403	return nfs4_init_callback(clp);
 404}
 405
 406static void nfs4_add_trunk(struct nfs_client *clp, struct nfs_client *old)
 407{
 408	struct sockaddr_storage clp_addr, old_addr;
 409	struct sockaddr *clp_sap = (struct sockaddr *)&clp_addr;
 410	struct sockaddr *old_sap = (struct sockaddr *)&old_addr;
 411	size_t clp_salen;
 412	struct xprt_create xprt_args = {
 413		.ident = old->cl_proto,
 414		.net = old->cl_net,
 415		.servername = old->cl_hostname,
 416	};
 417
 418	if (clp->cl_proto != old->cl_proto)
 419		return;
 420	clp_salen = rpc_peeraddr(clp->cl_rpcclient, clp_sap, sizeof(clp_addr));
 421	rpc_peeraddr(old->cl_rpcclient, old_sap, sizeof(old_addr));
 422
 423	if (clp_addr.ss_family != old_addr.ss_family)
 424		return;
 425
 426	xprt_args.dstaddr = clp_sap;
 427	xprt_args.addrlen = clp_salen;
 428
 429	rpc_clnt_add_xprt(old->cl_rpcclient, &xprt_args,
 430			  rpc_clnt_test_and_add_xprt, NULL);
 431}
 432
 433/**
 434 * nfs4_init_client - Initialise an NFS4 client record
 435 *
 436 * @clp: nfs_client to initialise
 437 * @cl_init: pointer to nfs_client_initdata
 438 *
 439 * Returns pointer to an NFS client, or an ERR_PTR value.
 440 */
 441struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 442				    const struct nfs_client_initdata *cl_init)
 443{
 
 
 444	struct nfs_client *old;
 445	int error;
 446
 447	if (clp->cl_cons_state == NFS_CS_READY)
 448		/* the client is initialised already */
 449		return clp;
 450
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 451	error = nfs4_init_client_minor_version(clp);
 452	if (error < 0)
 453		goto error;
 454
 455	error = nfs4_discover_server_trunking(clp, &old);
 456	if (error < 0)
 457		goto error;
 458
 459	if (clp != old) {
 460		clp->cl_preserve_clid = true;
 461		/*
 462		 * Mark the client as having failed initialization so other
 463		 * processes walking the nfs_client_list in nfs_match_client()
 464		 * won't try to use it.
 465		 */
 466		nfs_mark_client_ready(clp, -EPERM);
 467		if (old->cl_mvops->session_trunk)
 468			nfs4_add_trunk(clp, old);
 469	}
 470	clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
 471	nfs_put_client(clp);
 
 472	return old;
 473
 474error:
 475	nfs_mark_client_ready(clp, error);
 476	nfs_put_client(clp);
 477	return ERR_PTR(error);
 478}
 479
 480/*
 481 * SETCLIENTID just did a callback update with the callback ident in
 482 * "drop," but server trunking discovery claims "drop" and "keep" are
 483 * actually the same server.  Swap the callback IDs so that "keep"
 484 * will continue to use the callback ident the server now knows about,
 485 * and so that "keep"'s original callback ident is destroyed when
 486 * "drop" is freed.
 487 */
 488static void nfs4_swap_callback_idents(struct nfs_client *keep,
 489				      struct nfs_client *drop)
 490{
 491	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
 492	unsigned int save = keep->cl_cb_ident;
 493
 494	if (keep->cl_cb_ident == drop->cl_cb_ident)
 495		return;
 496
 497	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
 498		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
 499
 500	spin_lock(&nn->nfs_client_lock);
 501
 502	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
 503	keep->cl_cb_ident = drop->cl_cb_ident;
 504
 505	idr_replace(&nn->cb_ident_idr, drop, save);
 506	drop->cl_cb_ident = save;
 507
 508	spin_unlock(&nn->nfs_client_lock);
 509}
 510
 511static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
 512		const struct nfs_client *clp2)
 513{
 514	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
 515		return true;
 516	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
 517}
 518
 519static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
 520{
 521	return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
 522}
 523
 524static int nfs4_match_client(struct nfs_client  *pos,  struct nfs_client *new,
 525			     struct nfs_client **prev, struct nfs_net *nn)
 526{
 527	int status;
 528
 529	if (pos->rpc_ops != new->rpc_ops)
 530		return 1;
 531
 532	if (pos->cl_minorversion != new->cl_minorversion)
 533		return 1;
 534
 535	/* If "pos" isn't marked ready, we can't trust the
 536	 * remaining fields in "pos", especially the client
 537	 * ID and serverowner fields.  Wait for CREATE_SESSION
 538	 * to finish. */
 539	if (pos->cl_cons_state > NFS_CS_READY) {
 540		refcount_inc(&pos->cl_count);
 541		spin_unlock(&nn->nfs_client_lock);
 542
 543		nfs_put_client(*prev);
 544		*prev = pos;
 545
 546		status = nfs_wait_client_init_complete(pos);
 547		spin_lock(&nn->nfs_client_lock);
 548
 549		if (status < 0)
 550			return status;
 551	}
 552
 553	if (pos->cl_cons_state != NFS_CS_READY)
 554		return 1;
 555
 556	if (pos->cl_clientid != new->cl_clientid)
 557		return 1;
 558
 559	/* NFSv4.1 always uses the uniform string, however someone
 560	 * might switch the uniquifier string on us.
 561	 */
 562	if (!nfs4_match_client_owner_id(pos, new))
 563		return 1;
 564
 565	return 0;
 566}
 567
 568/**
 569 * nfs40_walk_client_list - Find server that recognizes a client ID
 570 *
 571 * @new: nfs_client with client ID to test
 572 * @result: OUT: found nfs_client, or new
 573 * @cred: credential to use for trunking test
 574 *
 575 * Returns zero, a negative errno, or a negative NFS4ERR status.
 576 * If zero is returned, an nfs_client pointer is planted in "result."
 577 *
 578 * NB: nfs40_walk_client_list() relies on the new nfs_client being
 579 *     the last nfs_client on the list.
 580 */
 581int nfs40_walk_client_list(struct nfs_client *new,
 582			   struct nfs_client **result,
 583			   const struct cred *cred)
 584{
 585	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 586	struct nfs_client *pos, *prev = NULL;
 587	struct nfs4_setclientid_res clid = {
 588		.clientid	= new->cl_clientid,
 589		.confirm	= new->cl_confirm,
 590	};
 591	int status = -NFS4ERR_STALE_CLIENTID;
 592
 593	spin_lock(&nn->nfs_client_lock);
 594	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 595
 596		if (pos == new)
 597			goto found;
 598
 599		status = nfs4_match_client(pos, new, &prev, nn);
 600		if (status < 0)
 601			goto out_unlock;
 602		if (status != 0)
 603			continue;
 604		/*
 605		 * We just sent a new SETCLIENTID, which should have
 606		 * caused the server to return a new cl_confirm.  So if
 607		 * cl_confirm is the same, then this is a different
 608		 * server that just returned the same cl_confirm by
 609		 * coincidence:
 610		 */
 611		if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
 612						       &new->cl_confirm))
 613			continue;
 614		/*
 615		 * But if the cl_confirm's are different, then the only
 616		 * way that a SETCLIENTID_CONFIRM to pos can succeed is
 617		 * if new and pos point to the same server:
 618		 */
 619found:
 620		refcount_inc(&pos->cl_count);
 621		spin_unlock(&nn->nfs_client_lock);
 622
 623		nfs_put_client(prev);
 624		prev = pos;
 625
 626		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 627		switch (status) {
 628		case -NFS4ERR_STALE_CLIENTID:
 629			break;
 630		case 0:
 631			nfs4_swap_callback_idents(pos, new);
 632			pos->cl_confirm = new->cl_confirm;
 633			nfs_mark_client_ready(pos, NFS_CS_READY);
 634
 635			prev = NULL;
 636			*result = pos;
 637			goto out;
 638		case -ERESTARTSYS:
 639		case -ETIMEDOUT:
 640			/* The callback path may have been inadvertently
 641			 * changed. Schedule recovery!
 642			 */
 643			nfs4_schedule_path_down_recovery(pos);
 644			goto out;
 645		default:
 646			goto out;
 647		}
 648
 649		spin_lock(&nn->nfs_client_lock);
 650	}
 651out_unlock:
 652	spin_unlock(&nn->nfs_client_lock);
 653
 654	/* No match found. The server lost our clientid */
 655out:
 656	nfs_put_client(prev);
 657	return status;
 658}
 659
 660#ifdef CONFIG_NFS_V4_1
 661/*
 662 * Returns true if the server major ids match
 663 */
 664bool
 665nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
 666				struct nfs41_server_owner *o2)
 667{
 668	if (o1->major_id_sz != o2->major_id_sz)
 669		return false;
 670	return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
 671}
 672
 673/*
 674 * Returns true if the server scopes match
 675 */
 676static bool
 677nfs4_check_server_scope(struct nfs41_server_scope *s1,
 678			struct nfs41_server_scope *s2)
 679{
 680	if (s1->server_scope_sz != s2->server_scope_sz)
 681		return false;
 682	return memcmp(s1->server_scope, s2->server_scope,
 683					s1->server_scope_sz) == 0;
 684}
 685
 686/**
 687 * nfs4_detect_session_trunking - Checks for session trunking.
 688 * @clp:    original mount nfs_client
 689 * @res:    result structure from an exchange_id using the original mount
 690 *          nfs_client with a new multi_addr transport
 691 * @xprt:   pointer to the transport to add.
 692 *
 693 * Called after a successful EXCHANGE_ID on a multi-addr connection.
 694 * Upon success, add the transport.
 695 *
 696 * Returns zero on success, otherwise -EINVAL
 697 *
 698 * Note: since the exchange_id for the new multi_addr transport uses the
 699 * same nfs_client from the original mount, the cl_owner_id is reused,
 700 * so eir_clientowner is the same.
 701 */
 702int nfs4_detect_session_trunking(struct nfs_client *clp,
 703				 struct nfs41_exchange_id_res *res,
 704				 struct rpc_xprt *xprt)
 705{
 706	/* Check eir_clientid */
 707	if (clp->cl_clientid != res->clientid)
 708		goto out_err;
 709
 710	/* Check eir_server_owner so_major_id */
 711	if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
 712					     res->server_owner))
 713		goto out_err;
 714
 715	/* Check eir_server_owner so_minor_id */
 716	if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
 717		goto out_err;
 718
 719	/* Check eir_server_scope */
 720	if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
 721		goto out_err;
 722
 723	pr_info("NFS:  %s: Session trunking succeeded for %s\n",
 724		clp->cl_hostname,
 725		xprt->address_strings[RPC_DISPLAY_ADDR]);
 726
 727	return 0;
 728out_err:
 729	pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
 730		xprt->address_strings[RPC_DISPLAY_ADDR]);
 731
 732	return -EINVAL;
 733}
 734
 735/**
 736 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 737 *
 738 * @new: nfs_client with client ID to test
 739 * @result: OUT: found nfs_client, or new
 740 * @cred: credential to use for trunking test
 741 *
 742 * Returns zero, a negative errno, or a negative NFS4ERR status.
 743 * If zero is returned, an nfs_client pointer is planted in "result."
 744 *
 745 * NB: nfs41_walk_client_list() relies on the new nfs_client being
 746 *     the last nfs_client on the list.
 747 */
 748int nfs41_walk_client_list(struct nfs_client *new,
 749			   struct nfs_client **result,
 750			   const struct cred *cred)
 751{
 752	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 753	struct nfs_client *pos, *prev = NULL;
 754	int status = -NFS4ERR_STALE_CLIENTID;
 755
 756	spin_lock(&nn->nfs_client_lock);
 757	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 758
 759		if (pos == new)
 760			goto found;
 761
 762		status = nfs4_match_client(pos, new, &prev, nn);
 763		if (status < 0)
 764			goto out;
 765		if (status != 0)
 766			continue;
 767
 768		/*
 769		 * Note that session trunking is just a special subcase of
 770		 * client id trunking. In either case, we want to fall back
 771		 * to using the existing nfs_client.
 772		 */
 773		if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
 774						     new->cl_serverowner))
 775			continue;
 776
 777found:
 778		refcount_inc(&pos->cl_count);
 779		*result = pos;
 780		status = 0;
 781		break;
 782	}
 783
 784out:
 785	spin_unlock(&nn->nfs_client_lock);
 786	nfs_put_client(prev);
 787	return status;
 788}
 789#endif	/* CONFIG_NFS_V4_1 */
 790
 791static void nfs4_destroy_server(struct nfs_server *server)
 792{
 793	LIST_HEAD(freeme);
 794
 795	nfs_server_return_all_delegations(server);
 796	unset_pnfs_layoutdriver(server);
 797	nfs4_purge_state_owners(server, &freeme);
 798	nfs4_free_state_owners(&freeme);
 799}
 800
 801/*
 802 * NFSv4.0 callback thread helper
 803 *
 804 * Find a client by callback identifier
 805 */
 806struct nfs_client *
 807nfs4_find_client_ident(struct net *net, int cb_ident)
 808{
 809	struct nfs_client *clp;
 810	struct nfs_net *nn = net_generic(net, nfs_net_id);
 811
 812	spin_lock(&nn->nfs_client_lock);
 813	clp = idr_find(&nn->cb_ident_idr, cb_ident);
 814	if (clp)
 815		refcount_inc(&clp->cl_count);
 816	spin_unlock(&nn->nfs_client_lock);
 817	return clp;
 818}
 819
 820#if defined(CONFIG_NFS_V4_1)
 821/* Common match routine for v4.0 and v4.1 callback services */
 822static bool nfs4_cb_match_client(const struct sockaddr *addr,
 823		struct nfs_client *clp, u32 minorversion)
 824{
 825	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 826
 827	/* Don't match clients that failed to initialise */
 828	if (!(clp->cl_cons_state == NFS_CS_READY ||
 829	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
 830		return false;
 831
 832	smp_rmb();
 833
 834	/* Match the version and minorversion */
 835	if (clp->rpc_ops->version != 4 ||
 836	    clp->cl_minorversion != minorversion)
 837		return false;
 838
 839	/* Match only the IP address, not the port number */
 840	return rpc_cmp_addr(addr, clap);
 841}
 842
 843/*
 844 * NFSv4.1 callback thread helper
 845 * For CB_COMPOUND calls, find a client by IP address, protocol version,
 846 * minorversion, and sessionID
 847 *
 848 * Returns NULL if no such client
 849 */
 850struct nfs_client *
 851nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 852			   struct nfs4_sessionid *sid, u32 minorversion)
 853{
 854	struct nfs_client *clp;
 855	struct nfs_net *nn = net_generic(net, nfs_net_id);
 856
 857	spin_lock(&nn->nfs_client_lock);
 858	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 859		if (!nfs4_cb_match_client(addr, clp, minorversion))
 860			continue;
 861
 862		if (!nfs4_has_session(clp))
 863			continue;
 864
 865		/* Match sessionid*/
 866		if (memcmp(clp->cl_session->sess_id.data,
 867		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 868			continue;
 869
 870		refcount_inc(&clp->cl_count);
 871		spin_unlock(&nn->nfs_client_lock);
 872		return clp;
 873	}
 874	spin_unlock(&nn->nfs_client_lock);
 875	return NULL;
 876}
 877
 878#else /* CONFIG_NFS_V4_1 */
 879
 880struct nfs_client *
 881nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 882			   struct nfs4_sessionid *sid, u32 minorversion)
 883{
 884	return NULL;
 885}
 886#endif /* CONFIG_NFS_V4_1 */
 887
 888/*
 889 * Set up an NFS4 client
 890 */
 891static int nfs4_set_client(struct nfs_server *server,
 892		const char *hostname,
 893		const struct sockaddr_storage *addr,
 894		const size_t addrlen,
 895		const char *ip_addr,
 896		int proto, const struct rpc_timeout *timeparms,
 897		u32 minorversion, unsigned int nconnect,
 898		unsigned int max_connect,
 899		struct net *net)
 900{
 901	struct nfs_client_initdata cl_init = {
 902		.hostname = hostname,
 903		.addr = addr,
 904		.addrlen = addrlen,
 905		.ip_addr = ip_addr,
 906		.nfs_mod = &nfs_v4,
 907		.proto = proto,
 908		.minorversion = minorversion,
 909		.net = net,
 910		.timeparms = timeparms,
 911		.cred = server->cred,
 912	};
 913	struct nfs_client *clp;
 914
 915	if (minorversion == 0)
 916		__set_bit(NFS_CS_REUSEPORT, &cl_init.init_flags);
 917	else
 918		cl_init.max_connect = max_connect;
 919	if (proto == XPRT_TRANSPORT_TCP)
 920		cl_init.nconnect = nconnect;
 921
 922	if (server->flags & NFS_MOUNT_NORESVPORT)
 923		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 924	if (server->options & NFS_OPTION_MIGRATION)
 925		__set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 926	if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
 927		__set_bit(NFS_CS_TSM_POSSIBLE, &cl_init.init_flags);
 928	server->port = rpc_get_port((struct sockaddr *)addr);
 929
 930	/* Allocate or find a client reference we can use */
 931	clp = nfs_get_client(&cl_init);
 932	if (IS_ERR(clp))
 933		return PTR_ERR(clp);
 934
 935	if (server->nfs_client == clp) {
 936		nfs_put_client(clp);
 937		return -ELOOP;
 938	}
 939
 940	/*
 941	 * Query for the lease time on clientid setup or renewal
 942	 *
 943	 * Note that this will be set on nfs_clients that were created
 944	 * only for the DS role and did not set this bit, but now will
 945	 * serve a dual role.
 946	 */
 947	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 948
 949	server->nfs_client = clp;
 950	return 0;
 951}
 952
 953/*
 954 * Set up a pNFS Data Server client.
 955 *
 956 * Return any existing nfs_client that matches server address,port,version
 957 * and minorversion.
 958 *
 959 * For a new nfs_client, use a soft mount (default), a low retrans and a
 960 * low timeout interval so that if a connection is lost, we retry through
 961 * the MDS.
 962 */
 963struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
 964		const struct sockaddr_storage *ds_addr, int ds_addrlen,
 965		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
 966		u32 minor_version)
 967{
 968	struct rpc_timeout ds_timeout;
 969	struct nfs_client *mds_clp = mds_srv->nfs_client;
 970	struct nfs_client_initdata cl_init = {
 971		.addr = ds_addr,
 972		.addrlen = ds_addrlen,
 973		.nodename = mds_clp->cl_rpcclient->cl_nodename,
 974		.ip_addr = mds_clp->cl_ipaddr,
 975		.nfs_mod = &nfs_v4,
 976		.proto = ds_proto,
 977		.minorversion = minor_version,
 978		.net = mds_clp->cl_net,
 979		.timeparms = &ds_timeout,
 980		.cred = mds_srv->cred,
 981	};
 982	char buf[INET6_ADDRSTRLEN + 1];
 983
 984	if (rpc_ntop((struct sockaddr *)ds_addr, buf, sizeof(buf)) <= 0)
 985		return ERR_PTR(-EINVAL);
 986	cl_init.hostname = buf;
 987
 988	if (mds_clp->cl_nconnect > 1 && ds_proto == XPRT_TRANSPORT_TCP) {
 989		cl_init.nconnect = mds_clp->cl_nconnect;
 990		cl_init.max_connect = NFS_MAX_TRANSPORTS;
 991	}
 992
 993	if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
 994		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 995
 996	/*
 997	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 998	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 999	 * (section 13.1 RFC 5661).
1000	 */
1001	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
1002	return nfs_get_client(&cl_init);
1003}
1004EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
1005
1006/*
1007 * Session has been established, and the client marked ready.
1008 * Limit the mount rsize, wsize and dtsize using negotiated fore
1009 * channel attributes.
1010 */
1011static void nfs4_session_limit_rwsize(struct nfs_server *server)
1012{
1013#ifdef CONFIG_NFS_V4_1
1014	struct nfs4_session *sess;
1015	u32 server_resp_sz;
1016	u32 server_rqst_sz;
1017
1018	if (!nfs4_has_session(server->nfs_client))
1019		return;
1020	sess = server->nfs_client->cl_session;
1021	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
1022	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
1023
1024	if (server->dtsize > server_resp_sz)
1025		server->dtsize = server_resp_sz;
1026	if (server->rsize > server_resp_sz)
1027		server->rsize = server_resp_sz;
1028	if (server->wsize > server_rqst_sz)
1029		server->wsize = server_rqst_sz;
1030#endif /* CONFIG_NFS_V4_1 */
1031}
1032
1033/*
1034 * Limit xattr sizes using the channel attributes.
1035 */
1036static void nfs4_session_limit_xasize(struct nfs_server *server)
1037{
1038#ifdef CONFIG_NFS_V4_2
1039	struct nfs4_session *sess;
1040	u32 server_gxa_sz;
1041	u32 server_sxa_sz;
1042	u32 server_lxa_sz;
1043
1044	if (!nfs4_has_session(server->nfs_client))
1045		return;
 
1046
1047	sess = server->nfs_client->cl_session;
 
 
1048
1049	server_gxa_sz = sess->fc_attrs.max_resp_sz - nfs42_maxgetxattr_overhead;
1050	server_sxa_sz = sess->fc_attrs.max_rqst_sz - nfs42_maxsetxattr_overhead;
1051	server_lxa_sz = sess->fc_attrs.max_resp_sz -
1052	    nfs42_maxlistxattrs_overhead;
1053
1054	if (server->gxasize > server_gxa_sz)
1055		server->gxasize = server_gxa_sz;
1056	if (server->sxasize > server_sxa_sz)
1057		server->sxasize = server_sxa_sz;
1058	if (server->lxasize > server_lxa_sz)
1059		server->lxasize = server_lxa_sz;
1060#endif
1061}
1062
1063void nfs4_server_set_init_caps(struct nfs_server *server)
1064{
1065	/* Set the basic capabilities */
1066	server->caps |= server->nfs_client->cl_mvops->init_caps;
1067	if (server->flags & NFS_MOUNT_NORDIRPLUS)
1068			server->caps &= ~NFS_CAP_READDIRPLUS;
1069	if (server->nfs_client->cl_proto == XPRT_TRANSPORT_RDMA)
1070		server->caps &= ~NFS_CAP_READ_PLUS;
1071
1072	/*
1073	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
1074	 * authentication.
1075	 */
1076	if (nfs4_disable_idmapping &&
1077			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
1078		server->caps |= NFS_CAP_UIDGID_NOMAP;
1079}
1080
1081static int nfs4_server_common_setup(struct nfs_server *server,
1082		struct nfs_fh *mntfh, bool auth_probe)
1083{
1084	int error;
1085
1086	/* data servers support only a subset of NFSv4.1 */
1087	if (is_ds_only_client(server->nfs_client))
1088		return -EPROTONOSUPPORT;
1089
1090	/* We must ensure the session is initialised first */
1091	error = nfs4_init_session(server->nfs_client);
1092	if (error < 0)
1093		goto out;
1094
1095	nfs4_server_set_init_caps(server);
1096
1097	/* Probe the root fh to retrieve its FSID and filehandle */
1098	error = nfs4_get_rootfh(server, mntfh, auth_probe);
1099	if (error < 0)
1100		goto out;
1101
1102	dprintk("Server FSID: %llx:%llx\n",
1103			(unsigned long long) server->fsid.major,
1104			(unsigned long long) server->fsid.minor);
1105	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1106
1107	error = nfs_probe_server(server, mntfh);
1108	if (error < 0)
1109		goto out;
1110
1111	nfs4_session_limit_rwsize(server);
1112	nfs4_session_limit_xasize(server);
1113
1114	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1115		server->namelen = NFS4_MAXNAMLEN;
1116
1117	nfs_server_insert_lists(server);
1118	server->mount_time = jiffies;
1119	server->destroy = nfs4_destroy_server;
1120out:
 
1121	return error;
1122}
1123
1124/*
1125 * Create a version 4 volume record
1126 */
1127static 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	int error;
1132
1133	nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
1134				ctx->timeo, ctx->retrans);
1135
1136	/* Initialise the client representation from the mount data */
1137	server->flags = ctx->flags;
1138	server->options = ctx->options;
1139	server->auth_info = ctx->auth_info;
1140
1141	/* Use the first specified auth flavor. If this flavor isn't
1142	 * allowed by the server, use the SECINFO path to try the
1143	 * other specified flavors */
1144	if (ctx->auth_info.flavor_len >= 1)
1145		ctx->selected_flavor = ctx->auth_info.flavors[0];
1146	else
1147		ctx->selected_flavor = RPC_AUTH_UNIX;
1148
1149	/* Get a client record */
1150	error = nfs4_set_client(server,
1151				ctx->nfs_server.hostname,
1152				&ctx->nfs_server._address,
1153				ctx->nfs_server.addrlen,
1154				ctx->client_address,
1155				ctx->nfs_server.protocol,
1156				&timeparms,
1157				ctx->minorversion,
1158				ctx->nfs_server.nconnect,
1159				ctx->nfs_server.max_connect,
1160				fc->net_ns);
1161	if (error < 0)
1162		return error;
1163
1164	if (ctx->rsize)
1165		server->rsize = nfs_io_size(ctx->rsize, server->nfs_client->cl_proto);
1166	if (ctx->wsize)
1167		server->wsize = nfs_io_size(ctx->wsize, server->nfs_client->cl_proto);
1168
1169	server->acregmin = ctx->acregmin * HZ;
1170	server->acregmax = ctx->acregmax * HZ;
1171	server->acdirmin = ctx->acdirmin * HZ;
1172	server->acdirmax = ctx->acdirmax * HZ;
1173	server->port     = ctx->nfs_server.port;
1174
1175	return nfs_init_server_rpcclient(server, &timeparms,
1176					 ctx->selected_flavor);
1177}
1178
1179/*
1180 * Create a version 4 volume record
1181 * - keyed on server and FSID
1182 */
1183struct nfs_server *nfs4_create_server(struct fs_context *fc)
 
 
 
1184{
1185	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1186	struct nfs_server *server;
1187	bool auth_probe;
1188	int error;
1189
1190	server = nfs_alloc_server();
1191	if (!server)
1192		return ERR_PTR(-ENOMEM);
1193
1194	server->cred = get_cred(fc->cred);
1195
1196	auth_probe = ctx->auth_info.flavor_len < 1;
1197
1198	/* set up the general RPC client */
1199	error = nfs4_init_server(server, fc);
1200	if (error < 0)
1201		goto error;
1202
1203	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1204	if (error < 0)
1205		goto error;
1206
1207	return server;
1208
1209error:
1210	nfs_free_server(server);
1211	return ERR_PTR(error);
1212}
1213
1214/*
1215 * Create an NFS4 referral server record
1216 */
1217struct nfs_server *nfs4_create_referral_server(struct fs_context *fc)
 
1218{
1219	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1220	struct nfs_client *parent_client;
1221	struct nfs_server *server, *parent_server;
1222	bool auth_probe;
1223	int error;
1224
1225	server = nfs_alloc_server();
1226	if (!server)
1227		return ERR_PTR(-ENOMEM);
1228
1229	parent_server = NFS_SB(ctx->clone_data.sb);
1230	parent_client = parent_server->nfs_client;
1231
1232	server->cred = get_cred(parent_server->cred);
1233
1234	/* Initialise the client representation from the parent server */
1235	nfs_server_copy_userdata(server, parent_server);
1236
1237	/* Get a client representation */
1238#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1239	rpc_set_port(&ctx->nfs_server.address, NFS_RDMA_PORT);
1240	error = nfs4_set_client(server,
1241				ctx->nfs_server.hostname,
1242				&ctx->nfs_server._address,
1243				ctx->nfs_server.addrlen,
1244				parent_client->cl_ipaddr,
1245				XPRT_TRANSPORT_RDMA,
1246				parent_server->client->cl_timeout,
1247				parent_client->cl_mvops->minor_version,
1248				parent_client->cl_nconnect,
1249				parent_client->cl_max_connect,
1250				parent_client->cl_net);
1251	if (!error)
1252		goto init_server;
1253#endif	/* IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA) */
1254
1255	rpc_set_port(&ctx->nfs_server.address, NFS_PORT);
1256	error = nfs4_set_client(server,
1257				ctx->nfs_server.hostname,
1258				&ctx->nfs_server._address,
1259				ctx->nfs_server.addrlen,
1260				parent_client->cl_ipaddr,
1261				XPRT_TRANSPORT_TCP,
1262				parent_server->client->cl_timeout,
1263				parent_client->cl_mvops->minor_version,
1264				parent_client->cl_nconnect,
1265				parent_client->cl_max_connect,
1266				parent_client->cl_net);
1267	if (error < 0)
1268		goto error;
1269
1270#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1271init_server:
1272#endif
1273	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout,
1274					  ctx->selected_flavor);
1275	if (error < 0)
1276		goto error;
1277
1278	auth_probe = parent_server->auth_info.flavor_len < 1;
1279
1280	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1281	if (error < 0)
1282		goto error;
1283
1284	return server;
1285
1286error:
1287	nfs_free_server(server);
1288	return ERR_PTR(error);
1289}
1290
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1291/**
1292 * nfs4_update_server - Move an nfs_server to a different nfs_client
1293 *
1294 * @server: represents FSID to be moved
1295 * @hostname: new end-point's hostname
1296 * @sap: new end-point's socket address
1297 * @salen: size of "sap"
1298 * @net: net namespace
1299 *
1300 * The nfs_server must be quiescent before this function is invoked.
1301 * Either its session is drained (NFSv4.1+), or its transport is
1302 * plugged and drained (NFSv4.0).
1303 *
1304 * Returns zero on success, or a negative errno value.
1305 */
1306int nfs4_update_server(struct nfs_server *server, const char *hostname,
1307		       struct sockaddr_storage *sap, size_t salen, struct net *net)
1308{
1309	struct nfs_client *clp = server->nfs_client;
1310	struct rpc_clnt *clnt = server->client;
1311	struct xprt_create xargs = {
1312		.ident		= clp->cl_proto,
1313		.net		= net,
1314		.dstaddr	= (struct sockaddr *)sap,
1315		.addrlen	= salen,
1316		.servername	= hostname,
1317	};
1318	char buf[INET6_ADDRSTRLEN + 1];
1319	struct sockaddr_storage address;
1320	struct sockaddr *localaddr = (struct sockaddr *)&address;
1321	int error;
1322
1323	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1324	if (error != 0)
1325		return error;
1326
1327	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1328	if (error != 0)
1329		return error;
1330
1331	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
1332		return -EAFNOSUPPORT;
1333
1334	nfs_server_remove_lists(server);
1335	set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1336	error = nfs4_set_client(server, hostname, sap, salen, buf,
1337				clp->cl_proto, clnt->cl_timeout,
1338				clp->cl_minorversion,
1339				clp->cl_nconnect, clp->cl_max_connect, net);
1340	clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1341	if (error != 0) {
1342		nfs_server_insert_lists(server);
1343		return error;
1344	}
1345	nfs_put_client(clp);
1346
1347	if (server->nfs_client->cl_hostname == NULL) {
1348		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1349		if (server->nfs_client->cl_hostname == NULL)
1350			return -ENOMEM;
1351	}
1352	nfs_server_insert_lists(server);
1353
1354	return nfs_probe_server(server, NFS_FH(d_inode(server->super->s_root)));
1355}
v5.4
   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_minorversion = cl_init->minorversion;
 220	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 221	clp->cl_mig_gen = 1;
 222#if IS_ENABLED(CONFIG_NFS_V4_1)
 223	init_waitqueue_head(&clp->cl_lock_waitq);
 224#endif
 225	INIT_LIST_HEAD(&clp->pending_cb_stateids);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 226	return clp;
 227
 228error:
 229	nfs_free_client(clp);
 230	return ERR_PTR(err);
 231}
 232
 233/*
 234 * Destroy the NFS4 callback service
 235 */
 236static void nfs4_destroy_callback(struct nfs_client *clp)
 237{
 238	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 239		nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 240}
 241
 242static void nfs4_shutdown_client(struct nfs_client *clp)
 243{
 244	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 245		nfs4_kill_renewd(clp);
 246	clp->cl_mvops->shutdown_client(clp);
 247	nfs4_destroy_callback(clp);
 248	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 249		nfs_idmap_delete(clp);
 250
 251	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 252	kfree(clp->cl_serverowner);
 253	kfree(clp->cl_serverscope);
 254	kfree(clp->cl_implid);
 255	kfree(clp->cl_owner_id);
 256}
 257
 258void nfs4_free_client(struct nfs_client *clp)
 259{
 260	nfs4_shutdown_client(clp);
 261	nfs_free_client(clp);
 262}
 263
 264/*
 265 * Initialize the NFS4 callback service
 266 */
 267static int nfs4_init_callback(struct nfs_client *clp)
 268{
 269	struct rpc_xprt *xprt;
 270	int error;
 271
 272	xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
 273
 274	if (nfs4_has_session(clp)) {
 275		error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
 276		if (error < 0)
 277			return error;
 278	}
 279
 280	error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
 281	if (error < 0) {
 282		dprintk("%s: failed to start callback. Error = %d\n",
 283			__func__, error);
 284		return error;
 285	}
 286	__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 287
 288	return 0;
 289}
 290
 291/**
 292 * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
 293 * @clp: nfs_client to initialize
 294 *
 295 * Returns zero on success, or a negative errno if some error occurred.
 296 */
 297int nfs40_init_client(struct nfs_client *clp)
 298{
 299	struct nfs4_slot_table *tbl;
 300	int ret;
 301
 302	tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
 303	if (tbl == NULL)
 304		return -ENOMEM;
 305
 306	ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
 307					"NFSv4.0 transport Slot table");
 308	if (ret) {
 
 309		kfree(tbl);
 310		return ret;
 311	}
 312
 313	clp->cl_slot_tbl = tbl;
 314	return 0;
 315}
 316
 317#if defined(CONFIG_NFS_V4_1)
 318
 319/**
 320 * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 321 * @clp: nfs_client to initialize
 322 *
 323 * Returns zero on success, or a negative errno if some error occurred.
 324 */
 325int nfs41_init_client(struct nfs_client *clp)
 326{
 327	struct nfs4_session *session = NULL;
 328
 329	/*
 330	 * Create the session and mark it expired.
 331	 * When a SEQUENCE operation encounters the expired session
 332	 * it will do session recovery to initialize it.
 333	 */
 334	session = nfs4_alloc_session(clp);
 335	if (!session)
 336		return -ENOMEM;
 337
 338	clp->cl_session = session;
 339
 340	/*
 341	 * The create session reply races with the server back
 342	 * channel probe. Mark the client NFS_CS_SESSION_INITING
 343	 * so that the client back channel can find the
 344	 * nfs_client struct
 345	 */
 346	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 347	return 0;
 348}
 349
 350#endif	/* CONFIG_NFS_V4_1 */
 351
 352/*
 353 * Initialize the minor version specific parts of an NFS4 client record
 354 */
 355static int nfs4_init_client_minor_version(struct nfs_client *clp)
 356{
 357	int ret;
 358
 359	ret = clp->cl_mvops->init_client(clp);
 360	if (ret)
 361		return ret;
 362	return nfs4_init_callback(clp);
 363}
 364
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 365/**
 366 * nfs4_init_client - Initialise an NFS4 client record
 367 *
 368 * @clp: nfs_client to initialise
 369 * @cl_init: pointer to nfs_client_initdata
 370 *
 371 * Returns pointer to an NFS client, or an ERR_PTR value.
 372 */
 373struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 374				    const struct nfs_client_initdata *cl_init)
 375{
 376	char buf[INET6_ADDRSTRLEN + 1];
 377	const char *ip_addr = cl_init->ip_addr;
 378	struct nfs_client *old;
 379	int error;
 380
 381	if (clp->cl_cons_state == NFS_CS_READY)
 382		/* the client is initialised already */
 383		return clp;
 384
 385	/* Check NFS protocol revision and initialize RPC op vector */
 386	clp->rpc_ops = &nfs_v4_clientops;
 387
 388	if (clp->cl_minorversion != 0)
 389		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 390	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
 391	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 392
 393	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
 394	if (error == -EINVAL)
 395		error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
 396	if (error < 0)
 397		goto error;
 398
 399	/* If no clientaddr= option was specified, find a usable cb address */
 400	if (ip_addr == NULL) {
 401		struct sockaddr_storage cb_addr;
 402		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
 403
 404		error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
 405		if (error < 0)
 406			goto error;
 407		error = rpc_ntop(sap, buf, sizeof(buf));
 408		if (error < 0)
 409			goto error;
 410		ip_addr = (const char *)buf;
 411	}
 412	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 413
 414	error = nfs_idmap_new(clp);
 415	if (error < 0) {
 416		dprintk("%s: failed to create idmapper. Error = %d\n",
 417			__func__, error);
 418		goto error;
 419	}
 420	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 421
 422	error = nfs4_init_client_minor_version(clp);
 423	if (error < 0)
 424		goto error;
 425
 426	error = nfs4_discover_server_trunking(clp, &old);
 427	if (error < 0)
 428		goto error;
 429
 430	if (clp != old) {
 431		clp->cl_preserve_clid = true;
 432		/*
 433		 * Mark the client as having failed initialization so other
 434		 * processes walking the nfs_client_list in nfs_match_client()
 435		 * won't try to use it.
 436		 */
 437		nfs_mark_client_ready(clp, -EPERM);
 
 
 438	}
 
 439	nfs_put_client(clp);
 440	clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
 441	return old;
 442
 443error:
 444	nfs_mark_client_ready(clp, error);
 445	nfs_put_client(clp);
 446	return ERR_PTR(error);
 447}
 448
 449/*
 450 * SETCLIENTID just did a callback update with the callback ident in
 451 * "drop," but server trunking discovery claims "drop" and "keep" are
 452 * actually the same server.  Swap the callback IDs so that "keep"
 453 * will continue to use the callback ident the server now knows about,
 454 * and so that "keep"'s original callback ident is destroyed when
 455 * "drop" is freed.
 456 */
 457static void nfs4_swap_callback_idents(struct nfs_client *keep,
 458				      struct nfs_client *drop)
 459{
 460	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
 461	unsigned int save = keep->cl_cb_ident;
 462
 463	if (keep->cl_cb_ident == drop->cl_cb_ident)
 464		return;
 465
 466	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
 467		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
 468
 469	spin_lock(&nn->nfs_client_lock);
 470
 471	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
 472	keep->cl_cb_ident = drop->cl_cb_ident;
 473
 474	idr_replace(&nn->cb_ident_idr, drop, save);
 475	drop->cl_cb_ident = save;
 476
 477	spin_unlock(&nn->nfs_client_lock);
 478}
 479
 480static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
 481		const struct nfs_client *clp2)
 482{
 483	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
 484		return true;
 485	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
 486}
 487
 488static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
 489{
 490	return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
 491}
 492
 493static int nfs4_match_client(struct nfs_client  *pos,  struct nfs_client *new,
 494			     struct nfs_client **prev, struct nfs_net *nn)
 495{
 496	int status;
 497
 498	if (pos->rpc_ops != new->rpc_ops)
 499		return 1;
 500
 501	if (pos->cl_minorversion != new->cl_minorversion)
 502		return 1;
 503
 504	/* If "pos" isn't marked ready, we can't trust the
 505	 * remaining fields in "pos", especially the client
 506	 * ID and serverowner fields.  Wait for CREATE_SESSION
 507	 * to finish. */
 508	if (pos->cl_cons_state > NFS_CS_READY) {
 509		refcount_inc(&pos->cl_count);
 510		spin_unlock(&nn->nfs_client_lock);
 511
 512		nfs_put_client(*prev);
 513		*prev = pos;
 514
 515		status = nfs_wait_client_init_complete(pos);
 516		spin_lock(&nn->nfs_client_lock);
 517
 518		if (status < 0)
 519			return status;
 520	}
 521
 522	if (pos->cl_cons_state != NFS_CS_READY)
 523		return 1;
 524
 525	if (pos->cl_clientid != new->cl_clientid)
 526		return 1;
 527
 528	/* NFSv4.1 always uses the uniform string, however someone
 529	 * might switch the uniquifier string on us.
 530	 */
 531	if (!nfs4_match_client_owner_id(pos, new))
 532		return 1;
 533
 534	return 0;
 535}
 536
 537/**
 538 * nfs40_walk_client_list - Find server that recognizes a client ID
 539 *
 540 * @new: nfs_client with client ID to test
 541 * @result: OUT: found nfs_client, or new
 542 * @cred: credential to use for trunking test
 543 *
 544 * Returns zero, a negative errno, or a negative NFS4ERR status.
 545 * If zero is returned, an nfs_client pointer is planted in "result."
 546 *
 547 * NB: nfs40_walk_client_list() relies on the new nfs_client being
 548 *     the last nfs_client on the list.
 549 */
 550int nfs40_walk_client_list(struct nfs_client *new,
 551			   struct nfs_client **result,
 552			   const struct cred *cred)
 553{
 554	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 555	struct nfs_client *pos, *prev = NULL;
 556	struct nfs4_setclientid_res clid = {
 557		.clientid	= new->cl_clientid,
 558		.confirm	= new->cl_confirm,
 559	};
 560	int status = -NFS4ERR_STALE_CLIENTID;
 561
 562	spin_lock(&nn->nfs_client_lock);
 563	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 564
 565		if (pos == new)
 566			goto found;
 567
 568		status = nfs4_match_client(pos, new, &prev, nn);
 569		if (status < 0)
 570			goto out_unlock;
 571		if (status != 0)
 572			continue;
 573		/*
 574		 * We just sent a new SETCLIENTID, which should have
 575		 * caused the server to return a new cl_confirm.  So if
 576		 * cl_confirm is the same, then this is a different
 577		 * server that just returned the same cl_confirm by
 578		 * coincidence:
 579		 */
 580		if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
 581						       &new->cl_confirm))
 582			continue;
 583		/*
 584		 * But if the cl_confirm's are different, then the only
 585		 * way that a SETCLIENTID_CONFIRM to pos can succeed is
 586		 * if new and pos point to the same server:
 587		 */
 588found:
 589		refcount_inc(&pos->cl_count);
 590		spin_unlock(&nn->nfs_client_lock);
 591
 592		nfs_put_client(prev);
 593		prev = pos;
 594
 595		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 596		switch (status) {
 597		case -NFS4ERR_STALE_CLIENTID:
 598			break;
 599		case 0:
 600			nfs4_swap_callback_idents(pos, new);
 601			pos->cl_confirm = new->cl_confirm;
 602			nfs_mark_client_ready(pos, NFS_CS_READY);
 603
 604			prev = NULL;
 605			*result = pos;
 606			goto out;
 607		case -ERESTARTSYS:
 608		case -ETIMEDOUT:
 609			/* The callback path may have been inadvertently
 610			 * changed. Schedule recovery!
 611			 */
 612			nfs4_schedule_path_down_recovery(pos);
 
 613		default:
 614			goto out;
 615		}
 616
 617		spin_lock(&nn->nfs_client_lock);
 618	}
 619out_unlock:
 620	spin_unlock(&nn->nfs_client_lock);
 621
 622	/* No match found. The server lost our clientid */
 623out:
 624	nfs_put_client(prev);
 625	return status;
 626}
 627
 628#ifdef CONFIG_NFS_V4_1
 629/*
 630 * Returns true if the server major ids match
 631 */
 632static bool
 633nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
 634				struct nfs41_server_owner *o2)
 635{
 636	if (o1->major_id_sz != o2->major_id_sz)
 637		return false;
 638	return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
 639}
 640
 641/*
 642 * Returns true if the server scopes match
 643 */
 644static bool
 645nfs4_check_server_scope(struct nfs41_server_scope *s1,
 646			struct nfs41_server_scope *s2)
 647{
 648	if (s1->server_scope_sz != s2->server_scope_sz)
 649		return false;
 650	return memcmp(s1->server_scope, s2->server_scope,
 651					s1->server_scope_sz) == 0;
 652}
 653
 654/**
 655 * nfs4_detect_session_trunking - Checks for session trunking.
 656 * @clp:    original mount nfs_client
 657 * @res:    result structure from an exchange_id using the original mount
 658 *          nfs_client with a new multi_addr transport
 659 * @xprt:   pointer to the transport to add.
 660 *
 661 * Called after a successful EXCHANGE_ID on a multi-addr connection.
 662 * Upon success, add the transport.
 663 *
 664 * Returns zero on success, otherwise -EINVAL
 665 *
 666 * Note: since the exchange_id for the new multi_addr transport uses the
 667 * same nfs_client from the original mount, the cl_owner_id is reused,
 668 * so eir_clientowner is the same.
 669 */
 670int nfs4_detect_session_trunking(struct nfs_client *clp,
 671				 struct nfs41_exchange_id_res *res,
 672				 struct rpc_xprt *xprt)
 673{
 674	/* Check eir_clientid */
 675	if (clp->cl_clientid != res->clientid)
 676		goto out_err;
 677
 678	/* Check eir_server_owner so_major_id */
 679	if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
 680					     res->server_owner))
 681		goto out_err;
 682
 683	/* Check eir_server_owner so_minor_id */
 684	if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
 685		goto out_err;
 686
 687	/* Check eir_server_scope */
 688	if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
 689		goto out_err;
 690
 691	pr_info("NFS:  %s: Session trunking succeeded for %s\n",
 692		clp->cl_hostname,
 693		xprt->address_strings[RPC_DISPLAY_ADDR]);
 694
 695	return 0;
 696out_err:
 697	pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
 698		xprt->address_strings[RPC_DISPLAY_ADDR]);
 699
 700	return -EINVAL;
 701}
 702
 703/**
 704 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 705 *
 706 * @new: nfs_client with client ID to test
 707 * @result: OUT: found nfs_client, or new
 708 * @cred: credential to use for trunking test
 709 *
 710 * Returns zero, a negative errno, or a negative NFS4ERR status.
 711 * If zero is returned, an nfs_client pointer is planted in "result."
 712 *
 713 * NB: nfs41_walk_client_list() relies on the new nfs_client being
 714 *     the last nfs_client on the list.
 715 */
 716int nfs41_walk_client_list(struct nfs_client *new,
 717			   struct nfs_client **result,
 718			   const struct cred *cred)
 719{
 720	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 721	struct nfs_client *pos, *prev = NULL;
 722	int status = -NFS4ERR_STALE_CLIENTID;
 723
 724	spin_lock(&nn->nfs_client_lock);
 725	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 726
 727		if (pos == new)
 728			goto found;
 729
 730		status = nfs4_match_client(pos, new, &prev, nn);
 731		if (status < 0)
 732			goto out;
 733		if (status != 0)
 734			continue;
 735
 736		/*
 737		 * Note that session trunking is just a special subcase of
 738		 * client id trunking. In either case, we want to fall back
 739		 * to using the existing nfs_client.
 740		 */
 741		if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
 742						     new->cl_serverowner))
 743			continue;
 744
 745found:
 746		refcount_inc(&pos->cl_count);
 747		*result = pos;
 748		status = 0;
 749		break;
 750	}
 751
 752out:
 753	spin_unlock(&nn->nfs_client_lock);
 754	nfs_put_client(prev);
 755	return status;
 756}
 757#endif	/* CONFIG_NFS_V4_1 */
 758
 759static void nfs4_destroy_server(struct nfs_server *server)
 760{
 761	LIST_HEAD(freeme);
 762
 763	nfs_server_return_all_delegations(server);
 764	unset_pnfs_layoutdriver(server);
 765	nfs4_purge_state_owners(server, &freeme);
 766	nfs4_free_state_owners(&freeme);
 767}
 768
 769/*
 770 * NFSv4.0 callback thread helper
 771 *
 772 * Find a client by callback identifier
 773 */
 774struct nfs_client *
 775nfs4_find_client_ident(struct net *net, int cb_ident)
 776{
 777	struct nfs_client *clp;
 778	struct nfs_net *nn = net_generic(net, nfs_net_id);
 779
 780	spin_lock(&nn->nfs_client_lock);
 781	clp = idr_find(&nn->cb_ident_idr, cb_ident);
 782	if (clp)
 783		refcount_inc(&clp->cl_count);
 784	spin_unlock(&nn->nfs_client_lock);
 785	return clp;
 786}
 787
 788#if defined(CONFIG_NFS_V4_1)
 789/* Common match routine for v4.0 and v4.1 callback services */
 790static bool nfs4_cb_match_client(const struct sockaddr *addr,
 791		struct nfs_client *clp, u32 minorversion)
 792{
 793	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 794
 795	/* Don't match clients that failed to initialise */
 796	if (!(clp->cl_cons_state == NFS_CS_READY ||
 797	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
 798		return false;
 799
 800	smp_rmb();
 801
 802	/* Match the version and minorversion */
 803	if (clp->rpc_ops->version != 4 ||
 804	    clp->cl_minorversion != minorversion)
 805		return false;
 806
 807	/* Match only the IP address, not the port number */
 808	return rpc_cmp_addr(addr, clap);
 809}
 810
 811/*
 812 * NFSv4.1 callback thread helper
 813 * For CB_COMPOUND calls, find a client by IP address, protocol version,
 814 * minorversion, and sessionID
 815 *
 816 * Returns NULL if no such client
 817 */
 818struct nfs_client *
 819nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 820			   struct nfs4_sessionid *sid, u32 minorversion)
 821{
 822	struct nfs_client *clp;
 823	struct nfs_net *nn = net_generic(net, nfs_net_id);
 824
 825	spin_lock(&nn->nfs_client_lock);
 826	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 827		if (!nfs4_cb_match_client(addr, clp, minorversion))
 828			continue;
 829
 830		if (!nfs4_has_session(clp))
 831			continue;
 832
 833		/* Match sessionid*/
 834		if (memcmp(clp->cl_session->sess_id.data,
 835		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 836			continue;
 837
 838		refcount_inc(&clp->cl_count);
 839		spin_unlock(&nn->nfs_client_lock);
 840		return clp;
 841	}
 842	spin_unlock(&nn->nfs_client_lock);
 843	return NULL;
 844}
 845
 846#else /* CONFIG_NFS_V4_1 */
 847
 848struct nfs_client *
 849nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 850			   struct nfs4_sessionid *sid, u32 minorversion)
 851{
 852	return NULL;
 853}
 854#endif /* CONFIG_NFS_V4_1 */
 855
 856/*
 857 * Set up an NFS4 client
 858 */
 859static int nfs4_set_client(struct nfs_server *server,
 860		const char *hostname,
 861		const struct sockaddr *addr,
 862		const size_t addrlen,
 863		const char *ip_addr,
 864		int proto, const struct rpc_timeout *timeparms,
 865		u32 minorversion, unsigned int nconnect,
 
 866		struct net *net)
 867{
 868	struct nfs_client_initdata cl_init = {
 869		.hostname = hostname,
 870		.addr = addr,
 871		.addrlen = addrlen,
 872		.ip_addr = ip_addr,
 873		.nfs_mod = &nfs_v4,
 874		.proto = proto,
 875		.minorversion = minorversion,
 876		.net = net,
 877		.timeparms = timeparms,
 878		.cred = server->cred,
 879	};
 880	struct nfs_client *clp;
 881
 882	if (minorversion > 0 && proto == XPRT_TRANSPORT_TCP)
 
 
 
 
 883		cl_init.nconnect = nconnect;
 
 884	if (server->flags & NFS_MOUNT_NORESVPORT)
 885		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 886	if (server->options & NFS_OPTION_MIGRATION)
 887		set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 888	if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
 889		set_bit(NFS_CS_TSM_POSSIBLE, &cl_init.init_flags);
 890	server->port = rpc_get_port(addr);
 891
 892	/* Allocate or find a client reference we can use */
 893	clp = nfs_get_client(&cl_init);
 894	if (IS_ERR(clp))
 895		return PTR_ERR(clp);
 896
 897	if (server->nfs_client == clp) {
 898		nfs_put_client(clp);
 899		return -ELOOP;
 900	}
 901
 902	/*
 903	 * Query for the lease time on clientid setup or renewal
 904	 *
 905	 * Note that this will be set on nfs_clients that were created
 906	 * only for the DS role and did not set this bit, but now will
 907	 * serve a dual role.
 908	 */
 909	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 910
 911	server->nfs_client = clp;
 912	return 0;
 913}
 914
 915/*
 916 * Set up a pNFS Data Server client.
 917 *
 918 * Return any existing nfs_client that matches server address,port,version
 919 * and minorversion.
 920 *
 921 * For a new nfs_client, use a soft mount (default), a low retrans and a
 922 * low timeout interval so that if a connection is lost, we retry through
 923 * the MDS.
 924 */
 925struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
 926		const struct sockaddr *ds_addr, int ds_addrlen,
 927		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
 928		u32 minor_version)
 929{
 930	struct rpc_timeout ds_timeout;
 931	struct nfs_client *mds_clp = mds_srv->nfs_client;
 932	struct nfs_client_initdata cl_init = {
 933		.addr = ds_addr,
 934		.addrlen = ds_addrlen,
 935		.nodename = mds_clp->cl_rpcclient->cl_nodename,
 936		.ip_addr = mds_clp->cl_ipaddr,
 937		.nfs_mod = &nfs_v4,
 938		.proto = ds_proto,
 939		.minorversion = minor_version,
 940		.net = mds_clp->cl_net,
 941		.timeparms = &ds_timeout,
 942		.cred = mds_srv->cred,
 943	};
 944	char buf[INET6_ADDRSTRLEN + 1];
 945
 946	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
 947		return ERR_PTR(-EINVAL);
 948	cl_init.hostname = buf;
 949
 950	if (mds_clp->cl_nconnect > 1 && ds_proto == XPRT_TRANSPORT_TCP)
 951		cl_init.nconnect = mds_clp->cl_nconnect;
 
 
 952
 953	if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
 954		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 955
 956	/*
 957	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 958	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 959	 * (section 13.1 RFC 5661).
 960	 */
 961	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 962	return nfs_get_client(&cl_init);
 963}
 964EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
 965
 966/*
 967 * Session has been established, and the client marked ready.
 968 * Limit the mount rsize, wsize and dtsize using negotiated fore
 969 * channel attributes.
 970 */
 971static void nfs4_session_limit_rwsize(struct nfs_server *server)
 972{
 973#ifdef CONFIG_NFS_V4_1
 974	struct nfs4_session *sess;
 975	u32 server_resp_sz;
 976	u32 server_rqst_sz;
 977
 978	if (!nfs4_has_session(server->nfs_client))
 979		return;
 980	sess = server->nfs_client->cl_session;
 981	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
 982	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
 983
 984	if (server->dtsize > server_resp_sz)
 985		server->dtsize = server_resp_sz;
 986	if (server->rsize > server_resp_sz)
 987		server->rsize = server_resp_sz;
 988	if (server->wsize > server_rqst_sz)
 989		server->wsize = server_rqst_sz;
 990#endif /* CONFIG_NFS_V4_1 */
 991}
 992
 993static int nfs4_server_common_setup(struct nfs_server *server,
 994		struct nfs_fh *mntfh, bool auth_probe)
 
 
 995{
 996	struct nfs_fattr *fattr;
 997	int error;
 
 
 
 998
 999	/* data servers support only a subset of NFSv4.1 */
1000	if (is_ds_only_client(server->nfs_client))
1001		return -EPROTONOSUPPORT;
1002
1003	fattr = nfs_alloc_fattr();
1004	if (fattr == NULL)
1005		return -ENOMEM;
1006
1007	/* We must ensure the session is initialised first */
1008	error = nfs4_init_session(server->nfs_client);
1009	if (error < 0)
1010		goto out;
 
 
 
 
 
 
 
 
 
1011
 
 
1012	/* Set the basic capabilities */
1013	server->caps |= server->nfs_client->cl_mvops->init_caps;
1014	if (server->flags & NFS_MOUNT_NORDIRPLUS)
1015			server->caps &= ~NFS_CAP_READDIRPLUS;
 
 
 
1016	/*
1017	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
1018	 * authentication.
1019	 */
1020	if (nfs4_disable_idmapping &&
1021			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
1022		server->caps |= NFS_CAP_UIDGID_NOMAP;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1023
 
1024
1025	/* Probe the root fh to retrieve its FSID and filehandle */
1026	error = nfs4_get_rootfh(server, mntfh, auth_probe);
1027	if (error < 0)
1028		goto out;
1029
1030	dprintk("Server FSID: %llx:%llx\n",
1031			(unsigned long long) server->fsid.major,
1032			(unsigned long long) server->fsid.minor);
1033	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1034
1035	error = nfs_probe_fsinfo(server, mntfh, fattr);
1036	if (error < 0)
1037		goto out;
1038
1039	nfs4_session_limit_rwsize(server);
 
1040
1041	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1042		server->namelen = NFS4_MAXNAMLEN;
1043
1044	nfs_server_insert_lists(server);
1045	server->mount_time = jiffies;
1046	server->destroy = nfs4_destroy_server;
1047out:
1048	nfs_free_fattr(fattr);
1049	return error;
1050}
1051
1052/*
1053 * Create a version 4 volume record
1054 */
1055static int nfs4_init_server(struct nfs_server *server,
1056		struct nfs_parsed_mount_data *data)
1057{
 
1058	struct rpc_timeout timeparms;
1059	int error;
1060
1061	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1062			data->timeo, data->retrans);
1063
1064	/* Initialise the client representation from the mount data */
1065	server->flags = data->flags;
1066	server->options = data->options;
1067	server->auth_info = data->auth_info;
1068
1069	/* Use the first specified auth flavor. If this flavor isn't
1070	 * allowed by the server, use the SECINFO path to try the
1071	 * other specified flavors */
1072	if (data->auth_info.flavor_len >= 1)
1073		data->selected_flavor = data->auth_info.flavors[0];
1074	else
1075		data->selected_flavor = RPC_AUTH_UNIX;
1076
1077	/* Get a client record */
1078	error = nfs4_set_client(server,
1079			data->nfs_server.hostname,
1080			(const struct sockaddr *)&data->nfs_server.address,
1081			data->nfs_server.addrlen,
1082			data->client_address,
1083			data->nfs_server.protocol,
1084			&timeparms,
1085			data->minorversion,
1086			data->nfs_server.nconnect,
1087			data->net);
 
1088	if (error < 0)
1089		return error;
1090
1091	if (data->rsize)
1092		server->rsize = nfs_block_size(data->rsize, NULL);
1093	if (data->wsize)
1094		server->wsize = nfs_block_size(data->wsize, NULL);
1095
1096	server->acregmin = data->acregmin * HZ;
1097	server->acregmax = data->acregmax * HZ;
1098	server->acdirmin = data->acdirmin * HZ;
1099	server->acdirmax = data->acdirmax * HZ;
1100	server->port     = data->nfs_server.port;
1101
1102	return nfs_init_server_rpcclient(server, &timeparms,
1103					 data->selected_flavor);
1104}
1105
1106/*
1107 * Create a version 4 volume record
1108 * - keyed on server and FSID
1109 */
1110/*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1111				      struct nfs_fh *mntfh)*/
1112struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1113				      struct nfs_subversion *nfs_mod)
1114{
 
1115	struct nfs_server *server;
1116	bool auth_probe;
1117	int error;
1118
1119	server = nfs_alloc_server();
1120	if (!server)
1121		return ERR_PTR(-ENOMEM);
1122
1123	server->cred = get_cred(current_cred());
1124
1125	auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1126
1127	/* set up the general RPC client */
1128	error = nfs4_init_server(server, mount_info->parsed);
1129	if (error < 0)
1130		goto error;
1131
1132	error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1133	if (error < 0)
1134		goto error;
1135
1136	return server;
1137
1138error:
1139	nfs_free_server(server);
1140	return ERR_PTR(error);
1141}
1142
1143/*
1144 * Create an NFS4 referral server record
1145 */
1146struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1147					       struct nfs_fh *mntfh)
1148{
 
1149	struct nfs_client *parent_client;
1150	struct nfs_server *server, *parent_server;
1151	bool auth_probe;
1152	int error;
1153
1154	server = nfs_alloc_server();
1155	if (!server)
1156		return ERR_PTR(-ENOMEM);
1157
1158	parent_server = NFS_SB(data->sb);
1159	parent_client = parent_server->nfs_client;
1160
1161	server->cred = get_cred(parent_server->cred);
1162
1163	/* Initialise the client representation from the parent server */
1164	nfs_server_copy_userdata(server, parent_server);
1165
1166	/* Get a client representation */
1167#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1168	rpc_set_port(data->addr, NFS_RDMA_PORT);
1169	error = nfs4_set_client(server, data->hostname,
1170				data->addr,
1171				data->addrlen,
 
1172				parent_client->cl_ipaddr,
1173				XPRT_TRANSPORT_RDMA,
1174				parent_server->client->cl_timeout,
1175				parent_client->cl_mvops->minor_version,
1176				parent_client->cl_nconnect,
 
1177				parent_client->cl_net);
1178	if (!error)
1179		goto init_server;
1180#endif	/* IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA) */
1181
1182	rpc_set_port(data->addr, NFS_PORT);
1183	error = nfs4_set_client(server, data->hostname,
1184				data->addr,
1185				data->addrlen,
 
1186				parent_client->cl_ipaddr,
1187				XPRT_TRANSPORT_TCP,
1188				parent_server->client->cl_timeout,
1189				parent_client->cl_mvops->minor_version,
1190				parent_client->cl_nconnect,
 
1191				parent_client->cl_net);
1192	if (error < 0)
1193		goto error;
1194
1195#if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1196init_server:
1197#endif
1198	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
 
1199	if (error < 0)
1200		goto error;
1201
1202	auth_probe = parent_server->auth_info.flavor_len < 1;
1203
1204	error = nfs4_server_common_setup(server, mntfh, auth_probe);
1205	if (error < 0)
1206		goto error;
1207
1208	return server;
1209
1210error:
1211	nfs_free_server(server);
1212	return ERR_PTR(error);
1213}
1214
1215/*
1216 * Grab the destination's particulars, including lease expiry time.
1217 *
1218 * Returns zero if probe succeeded and retrieved FSID matches the FSID
1219 * we have cached.
1220 */
1221static int nfs_probe_destination(struct nfs_server *server)
1222{
1223	struct inode *inode = d_inode(server->super->s_root);
1224	struct nfs_fattr *fattr;
1225	int error;
1226
1227	fattr = nfs_alloc_fattr();
1228	if (fattr == NULL)
1229		return -ENOMEM;
1230
1231	/* Sanity: the probe won't work if the destination server
1232	 * does not recognize the migrated FH. */
1233	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1234
1235	nfs_free_fattr(fattr);
1236	return error;
1237}
1238
1239/**
1240 * nfs4_update_server - Move an nfs_server to a different nfs_client
1241 *
1242 * @server: represents FSID to be moved
1243 * @hostname: new end-point's hostname
1244 * @sap: new end-point's socket address
1245 * @salen: size of "sap"
1246 * @net: net namespace
1247 *
1248 * The nfs_server must be quiescent before this function is invoked.
1249 * Either its session is drained (NFSv4.1+), or its transport is
1250 * plugged and drained (NFSv4.0).
1251 *
1252 * Returns zero on success, or a negative errno value.
1253 */
1254int nfs4_update_server(struct nfs_server *server, const char *hostname,
1255		       struct sockaddr *sap, size_t salen, struct net *net)
1256{
1257	struct nfs_client *clp = server->nfs_client;
1258	struct rpc_clnt *clnt = server->client;
1259	struct xprt_create xargs = {
1260		.ident		= clp->cl_proto,
1261		.net		= net,
1262		.dstaddr	= sap,
1263		.addrlen	= salen,
1264		.servername	= hostname,
1265	};
1266	char buf[INET6_ADDRSTRLEN + 1];
1267	struct sockaddr_storage address;
1268	struct sockaddr *localaddr = (struct sockaddr *)&address;
1269	int error;
1270
1271	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1272	if (error != 0)
1273		return error;
1274
1275	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1276	if (error != 0)
1277		return error;
1278
1279	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
1280		return -EAFNOSUPPORT;
1281
1282	nfs_server_remove_lists(server);
1283	set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1284	error = nfs4_set_client(server, hostname, sap, salen, buf,
1285				clp->cl_proto, clnt->cl_timeout,
1286				clp->cl_minorversion,
1287				clp->cl_nconnect, net);
1288	clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1289	if (error != 0) {
1290		nfs_server_insert_lists(server);
1291		return error;
1292	}
1293	nfs_put_client(clp);
1294
1295	if (server->nfs_client->cl_hostname == NULL)
1296		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
 
 
 
1297	nfs_server_insert_lists(server);
1298
1299	return nfs_probe_destination(server);
1300}