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v4.17
 
   1/*
   2 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
   3 * Written by David Howells (dhowells@redhat.com)
   4 */
   5#include <linux/module.h>
   6#include <linux/nfs_fs.h>
   7#include <linux/nfs_mount.h>
   8#include <linux/sunrpc/addr.h>
   9#include <linux/sunrpc/auth.h>
  10#include <linux/sunrpc/xprt.h>
  11#include <linux/sunrpc/bc_xprt.h>
  12#include <linux/sunrpc/rpc_pipe_fs.h>
  13#include "internal.h"
  14#include "callback.h"
  15#include "delegation.h"
  16#include "nfs4session.h"
  17#include "nfs4idmap.h"
  18#include "pnfs.h"
  19#include "netns.h"
  20
  21#define NFSDBG_FACILITY		NFSDBG_CLIENT
  22
  23/*
  24 * Get a unique NFSv4.0 callback identifier which will be used
  25 * by the V4.0 callback service to lookup the nfs_client struct
  26 */
  27static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
  28{
  29	int ret = 0;
  30	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  31
  32	if (clp->rpc_ops->version != 4 || minorversion != 0)
  33		return ret;
  34	idr_preload(GFP_KERNEL);
  35	spin_lock(&nn->nfs_client_lock);
  36	ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
  37	if (ret >= 0)
  38		clp->cl_cb_ident = ret;
  39	spin_unlock(&nn->nfs_client_lock);
  40	idr_preload_end();
  41	return ret < 0 ? ret : 0;
  42}
  43
  44#ifdef CONFIG_NFS_V4_1
  45/**
  46 * Per auth flavor data server rpc clients
  47 */
  48struct nfs4_ds_server {
  49	struct list_head	list;   /* ds_clp->cl_ds_clients */
  50	struct rpc_clnt		*rpc_clnt;
  51};
  52
  53/**
  54 * Common lookup case for DS I/O
 
 
  55 */
  56static struct nfs4_ds_server *
  57nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  58{
  59	struct nfs4_ds_server *dss;
  60
  61	rcu_read_lock();
  62	list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
  63		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  64			continue;
  65		goto out;
  66	}
  67	dss = NULL;
  68out:
  69	rcu_read_unlock();
  70	return dss;
  71}
  72
  73static struct nfs4_ds_server *
  74nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
  75			   struct nfs4_ds_server *new)
  76{
  77	struct nfs4_ds_server *dss;
  78
  79	spin_lock(&ds_clp->cl_lock);
  80	list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
  81		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  82			continue;
  83		goto out;
  84	}
  85	if (new)
  86		list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
  87	dss = new;
  88out:
  89	spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
  90	return dss;
  91}
  92
  93static struct nfs4_ds_server *
  94nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  95{
  96	struct nfs4_ds_server *dss;
  97
  98	dss = kmalloc(sizeof(*dss), GFP_NOFS);
  99	if (dss == NULL)
 100		return ERR_PTR(-ENOMEM);
 101
 102	dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
 103	if (IS_ERR(dss->rpc_clnt)) {
 104		int err = PTR_ERR(dss->rpc_clnt);
 105		kfree (dss);
 106		return ERR_PTR(err);
 107	}
 108	INIT_LIST_HEAD(&dss->list);
 109
 110	return dss;
 111}
 112
 113static void
 114nfs4_free_ds_server(struct nfs4_ds_server *dss)
 115{
 116	rpc_release_client(dss->rpc_clnt);
 117	kfree(dss);
 118}
 119
 120/**
 121* Find or create a DS rpc client with th MDS server rpc client auth flavor
 122* in the nfs_client cl_ds_clients list.
 123*/
 
 
 
 
 124struct rpc_clnt *
 125nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
 126{
 127	struct nfs4_ds_server *dss, *new;
 128	rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
 129
 130	dss = nfs4_find_ds_client(ds_clp, flavor);
 131	if (dss != NULL)
 132		goto out;
 133	new = nfs4_alloc_ds_server(ds_clp, flavor);
 134	if (IS_ERR(new))
 135		return ERR_CAST(new);
 136	dss = nfs4_add_ds_client(ds_clp, flavor, new);
 137	if (dss != new)
 138		nfs4_free_ds_server(new);
 139out:
 140	return dss->rpc_clnt;
 141}
 142EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
 143
 144static void
 145nfs4_shutdown_ds_clients(struct nfs_client *clp)
 146{
 147	struct nfs4_ds_server *dss;
 148	LIST_HEAD(shutdown_list);
 149
 150	while (!list_empty(&clp->cl_ds_clients)) {
 151		dss = list_entry(clp->cl_ds_clients.next,
 152					struct nfs4_ds_server, list);
 153		list_del(&dss->list);
 154		rpc_shutdown_client(dss->rpc_clnt);
 155		kfree (dss);
 156	}
 157}
 158
 
 
 
 
 
 
 
 
 
 
 
 
 
 159void nfs41_shutdown_client(struct nfs_client *clp)
 160{
 161	if (nfs4_has_session(clp)) {
 
 162		nfs4_shutdown_ds_clients(clp);
 163		nfs4_destroy_session(clp->cl_session);
 164		nfs4_destroy_clientid(clp);
 165	}
 166
 167}
 168#endif	/* CONFIG_NFS_V4_1 */
 169
 170void nfs40_shutdown_client(struct nfs_client *clp)
 171{
 172	if (clp->cl_slot_tbl) {
 173		nfs4_shutdown_slot_table(clp->cl_slot_tbl);
 174		kfree(clp->cl_slot_tbl);
 175	}
 176}
 177
 178struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
 179{
 180	int err;
 
 181	struct nfs_client *clp = nfs_alloc_client(cl_init);
 
 
 182	if (IS_ERR(clp))
 183		return clp;
 184
 185	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
 186	if (err)
 187		goto error;
 188
 189	if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
 190		err = -EINVAL;
 191		goto error;
 192	}
 193
 194	spin_lock_init(&clp->cl_lock);
 195	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
 196	INIT_LIST_HEAD(&clp->cl_ds_clients);
 197	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
 198	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 199	clp->cl_minorversion = cl_init->minorversion;
 200	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 201	clp->cl_mig_gen = 1;
 202#if IS_ENABLED(CONFIG_NFS_V4_1)
 203	init_waitqueue_head(&clp->cl_lock_waitq);
 204#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 205	return clp;
 206
 207error:
 208	nfs_free_client(clp);
 209	return ERR_PTR(err);
 210}
 211
 212/*
 213 * Destroy the NFS4 callback service
 214 */
 215static void nfs4_destroy_callback(struct nfs_client *clp)
 216{
 217	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 218		nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 219}
 220
 221static void nfs4_shutdown_client(struct nfs_client *clp)
 222{
 223	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 224		nfs4_kill_renewd(clp);
 225	clp->cl_mvops->shutdown_client(clp);
 226	nfs4_destroy_callback(clp);
 227	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 228		nfs_idmap_delete(clp);
 229
 230	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 231	kfree(clp->cl_serverowner);
 232	kfree(clp->cl_serverscope);
 233	kfree(clp->cl_implid);
 234	kfree(clp->cl_owner_id);
 235}
 236
 237void nfs4_free_client(struct nfs_client *clp)
 238{
 239	nfs4_shutdown_client(clp);
 240	nfs_free_client(clp);
 241}
 242
 243/*
 244 * Initialize the NFS4 callback service
 245 */
 246static int nfs4_init_callback(struct nfs_client *clp)
 247{
 248	struct rpc_xprt *xprt;
 249	int error;
 250
 251	xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
 252
 253	if (nfs4_has_session(clp)) {
 254		error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
 255		if (error < 0)
 256			return error;
 257	}
 258
 259	error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
 260	if (error < 0) {
 261		dprintk("%s: failed to start callback. Error = %d\n",
 262			__func__, error);
 263		return error;
 264	}
 265	__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 266
 267	return 0;
 268}
 269
 270/**
 271 * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
 272 * @clp - nfs_client to initialize
 273 *
 274 * Returns zero on success, or a negative errno if some error occurred.
 275 */
 276int nfs40_init_client(struct nfs_client *clp)
 277{
 278	struct nfs4_slot_table *tbl;
 279	int ret;
 280
 281	tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
 282	if (tbl == NULL)
 283		return -ENOMEM;
 284
 285	ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
 286					"NFSv4.0 transport Slot table");
 287	if (ret) {
 288		kfree(tbl);
 289		return ret;
 290	}
 291
 292	clp->cl_slot_tbl = tbl;
 293	return 0;
 294}
 295
 296#if defined(CONFIG_NFS_V4_1)
 297
 298/**
 299 * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 300 * @clp - nfs_client to initialize
 301 *
 302 * Returns zero on success, or a negative errno if some error occurred.
 303 */
 304int nfs41_init_client(struct nfs_client *clp)
 305{
 306	struct nfs4_session *session = NULL;
 307
 308	/*
 309	 * Create the session and mark it expired.
 310	 * When a SEQUENCE operation encounters the expired session
 311	 * it will do session recovery to initialize it.
 312	 */
 313	session = nfs4_alloc_session(clp);
 314	if (!session)
 315		return -ENOMEM;
 316
 317	clp->cl_session = session;
 318
 319	/*
 320	 * The create session reply races with the server back
 321	 * channel probe. Mark the client NFS_CS_SESSION_INITING
 322	 * so that the client back channel can find the
 323	 * nfs_client struct
 324	 */
 325	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 326	return 0;
 327}
 328
 329#endif	/* CONFIG_NFS_V4_1 */
 330
 331/*
 332 * Initialize the minor version specific parts of an NFS4 client record
 333 */
 334static int nfs4_init_client_minor_version(struct nfs_client *clp)
 335{
 336	int ret;
 337
 338	ret = clp->cl_mvops->init_client(clp);
 339	if (ret)
 340		return ret;
 341	return nfs4_init_callback(clp);
 342}
 343
 344/**
 345 * nfs4_init_client - Initialise an NFS4 client record
 346 *
 347 * @clp: nfs_client to initialise
 348 * @timeparms: timeout parameters for underlying RPC transport
 349 * @ip_addr: callback IP address in presentation format
 350 * @authflavor: authentication flavor for underlying RPC transport
 351 *
 352 * Returns pointer to an NFS client, or an ERR_PTR value.
 353 */
 354struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 355				    const struct nfs_client_initdata *cl_init)
 356{
 357	char buf[INET6_ADDRSTRLEN + 1];
 358	const char *ip_addr = cl_init->ip_addr;
 359	struct nfs_client *old;
 360	int error;
 361
 362	if (clp->cl_cons_state == NFS_CS_READY)
 363		/* the client is initialised already */
 364		return clp;
 365
 366	/* Check NFS protocol revision and initialize RPC op vector */
 367	clp->rpc_ops = &nfs_v4_clientops;
 368
 369	if (clp->cl_minorversion != 0)
 370		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 371	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
 372	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 373
 374	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
 375	if (error == -EINVAL)
 376		error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
 377	if (error < 0)
 378		goto error;
 379
 380	/* If no clientaddr= option was specified, find a usable cb address */
 381	if (ip_addr == NULL) {
 382		struct sockaddr_storage cb_addr;
 383		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
 384
 385		error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
 386		if (error < 0)
 387			goto error;
 388		error = rpc_ntop(sap, buf, sizeof(buf));
 389		if (error < 0)
 390			goto error;
 391		ip_addr = (const char *)buf;
 392	}
 393	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 394
 395	error = nfs_idmap_new(clp);
 396	if (error < 0) {
 397		dprintk("%s: failed to create idmapper. Error = %d\n",
 398			__func__, error);
 399		goto error;
 400	}
 401	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 402
 403	error = nfs4_init_client_minor_version(clp);
 404	if (error < 0)
 405		goto error;
 406
 407	error = nfs4_discover_server_trunking(clp, &old);
 408	if (error < 0)
 409		goto error;
 410
 411	if (clp != old) {
 412		clp->cl_preserve_clid = true;
 413		/*
 414		 * Mark the client as having failed initialization so other
 415		 * processes walking the nfs_client_list in nfs_match_client()
 416		 * won't try to use it.
 417		 */
 418		nfs_mark_client_ready(clp, -EPERM);
 419	}
 420	nfs_put_client(clp);
 421	clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
 
 422	return old;
 423
 424error:
 425	nfs_mark_client_ready(clp, error);
 426	nfs_put_client(clp);
 427	return ERR_PTR(error);
 428}
 429
 430/*
 431 * SETCLIENTID just did a callback update with the callback ident in
 432 * "drop," but server trunking discovery claims "drop" and "keep" are
 433 * actually the same server.  Swap the callback IDs so that "keep"
 434 * will continue to use the callback ident the server now knows about,
 435 * and so that "keep"'s original callback ident is destroyed when
 436 * "drop" is freed.
 437 */
 438static void nfs4_swap_callback_idents(struct nfs_client *keep,
 439				      struct nfs_client *drop)
 440{
 441	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
 442	unsigned int save = keep->cl_cb_ident;
 443
 444	if (keep->cl_cb_ident == drop->cl_cb_ident)
 445		return;
 446
 447	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
 448		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
 449
 450	spin_lock(&nn->nfs_client_lock);
 451
 452	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
 453	keep->cl_cb_ident = drop->cl_cb_ident;
 454
 455	idr_replace(&nn->cb_ident_idr, drop, save);
 456	drop->cl_cb_ident = save;
 457
 458	spin_unlock(&nn->nfs_client_lock);
 459}
 460
 461static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
 462		const struct nfs_client *clp2)
 463{
 464	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
 465		return true;
 466	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
 467}
 468
 469static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
 470{
 471	return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
 472}
 473
 474static int nfs4_match_client(struct nfs_client  *pos,  struct nfs_client *new,
 475			     struct nfs_client **prev, struct nfs_net *nn)
 476{
 477	int status;
 478
 479	if (pos->rpc_ops != new->rpc_ops)
 480		return 1;
 481
 482	if (pos->cl_minorversion != new->cl_minorversion)
 483		return 1;
 484
 485	/* If "pos" isn't marked ready, we can't trust the
 486	 * remaining fields in "pos", especially the client
 487	 * ID and serverowner fields.  Wait for CREATE_SESSION
 488	 * to finish. */
 489	if (pos->cl_cons_state > NFS_CS_READY) {
 490		refcount_inc(&pos->cl_count);
 491		spin_unlock(&nn->nfs_client_lock);
 492
 493		nfs_put_client(*prev);
 494		*prev = pos;
 495
 496		status = nfs_wait_client_init_complete(pos);
 497		spin_lock(&nn->nfs_client_lock);
 498
 499		if (status < 0)
 500			return status;
 501	}
 502
 503	if (pos->cl_cons_state != NFS_CS_READY)
 504		return 1;
 505
 506	if (pos->cl_clientid != new->cl_clientid)
 507		return 1;
 508
 509	/* NFSv4.1 always uses the uniform string, however someone
 510	 * might switch the uniquifier string on us.
 511	 */
 512	if (!nfs4_match_client_owner_id(pos, new))
 513		return 1;
 514
 515	return 0;
 516}
 517
 518/**
 519 * nfs40_walk_client_list - Find server that recognizes a client ID
 520 *
 521 * @new: nfs_client with client ID to test
 522 * @result: OUT: found nfs_client, or new
 523 * @cred: credential to use for trunking test
 524 *
 525 * Returns zero, a negative errno, or a negative NFS4ERR status.
 526 * If zero is returned, an nfs_client pointer is planted in "result."
 527 *
 528 * NB: nfs40_walk_client_list() relies on the new nfs_client being
 529 *     the last nfs_client on the list.
 530 */
 531int nfs40_walk_client_list(struct nfs_client *new,
 532			   struct nfs_client **result,
 533			   struct rpc_cred *cred)
 534{
 535	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 536	struct nfs_client *pos, *prev = NULL;
 537	struct nfs4_setclientid_res clid = {
 538		.clientid	= new->cl_clientid,
 539		.confirm	= new->cl_confirm,
 540	};
 541	int status = -NFS4ERR_STALE_CLIENTID;
 542
 543	spin_lock(&nn->nfs_client_lock);
 544	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 545
 546		if (pos == new)
 547			goto found;
 548
 549		status = nfs4_match_client(pos, new, &prev, nn);
 550		if (status < 0)
 551			goto out_unlock;
 552		if (status != 0)
 553			continue;
 554		/*
 555		 * We just sent a new SETCLIENTID, which should have
 556		 * caused the server to return a new cl_confirm.  So if
 557		 * cl_confirm is the same, then this is a different
 558		 * server that just returned the same cl_confirm by
 559		 * coincidence:
 560		 */
 561		if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
 562						       &new->cl_confirm))
 563			continue;
 564		/*
 565		 * But if the cl_confirm's are different, then the only
 566		 * way that a SETCLIENTID_CONFIRM to pos can succeed is
 567		 * if new and pos point to the same server:
 568		 */
 569found:
 570		refcount_inc(&pos->cl_count);
 571		spin_unlock(&nn->nfs_client_lock);
 572
 573		nfs_put_client(prev);
 574		prev = pos;
 575
 576		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 577		switch (status) {
 578		case -NFS4ERR_STALE_CLIENTID:
 579			break;
 580		case 0:
 581			nfs4_swap_callback_idents(pos, new);
 582			pos->cl_confirm = new->cl_confirm;
 583			nfs_mark_client_ready(pos, NFS_CS_READY);
 584
 585			prev = NULL;
 586			*result = pos;
 587			goto out;
 588		case -ERESTARTSYS:
 589		case -ETIMEDOUT:
 590			/* The callback path may have been inadvertently
 591			 * changed. Schedule recovery!
 592			 */
 593			nfs4_schedule_path_down_recovery(pos);
 
 594		default:
 595			goto out;
 596		}
 597
 598		spin_lock(&nn->nfs_client_lock);
 599	}
 600out_unlock:
 601	spin_unlock(&nn->nfs_client_lock);
 602
 603	/* No match found. The server lost our clientid */
 604out:
 605	nfs_put_client(prev);
 606	return status;
 607}
 608
 609#ifdef CONFIG_NFS_V4_1
 610/*
 611 * Returns true if the server major ids match
 612 */
 613static bool
 614nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
 615				struct nfs41_server_owner *o2)
 616{
 617	if (o1->major_id_sz != o2->major_id_sz)
 618		return false;
 619	return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
 620}
 621
 622/*
 623 * Returns true if the server scopes match
 624 */
 625static bool
 626nfs4_check_server_scope(struct nfs41_server_scope *s1,
 627			struct nfs41_server_scope *s2)
 628{
 629	if (s1->server_scope_sz != s2->server_scope_sz)
 630		return false;
 631	return memcmp(s1->server_scope, s2->server_scope,
 632					s1->server_scope_sz) == 0;
 633}
 634
 635/**
 636 * nfs4_detect_session_trunking - Checks for session trunking.
 637 *
 638 * Called after a successful EXCHANGE_ID on a multi-addr connection.
 639 * Upon success, add the transport.
 640 *
 641 * @clp:    original mount nfs_client
 642 * @res:    result structure from an exchange_id using the original mount
 643 *          nfs_client with a new multi_addr transport
 
 
 
 
 644 *
 645 * Returns zero on success, otherwise -EINVAL
 646 *
 647 * Note: since the exchange_id for the new multi_addr transport uses the
 648 * same nfs_client from the original mount, the cl_owner_id is reused,
 649 * so eir_clientowner is the same.
 650 */
 651int nfs4_detect_session_trunking(struct nfs_client *clp,
 652				 struct nfs41_exchange_id_res *res,
 653				 struct rpc_xprt *xprt)
 654{
 655	/* Check eir_clientid */
 656	if (clp->cl_clientid != res->clientid)
 657		goto out_err;
 658
 659	/* Check eir_server_owner so_major_id */
 660	if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
 661					     res->server_owner))
 662		goto out_err;
 663
 664	/* Check eir_server_owner so_minor_id */
 665	if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
 666		goto out_err;
 667
 668	/* Check eir_server_scope */
 669	if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
 670		goto out_err;
 671
 672	pr_info("NFS:  %s: Session trunking succeeded for %s\n",
 673		clp->cl_hostname,
 674		xprt->address_strings[RPC_DISPLAY_ADDR]);
 675
 676	return 0;
 677out_err:
 678	pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
 679		xprt->address_strings[RPC_DISPLAY_ADDR]);
 680
 681	return -EINVAL;
 682}
 683
 684/**
 685 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 686 *
 687 * @new: nfs_client with client ID to test
 688 * @result: OUT: found nfs_client, or new
 689 * @cred: credential to use for trunking test
 690 *
 691 * Returns zero, a negative errno, or a negative NFS4ERR status.
 692 * If zero is returned, an nfs_client pointer is planted in "result."
 693 *
 694 * NB: nfs41_walk_client_list() relies on the new nfs_client being
 695 *     the last nfs_client on the list.
 696 */
 697int nfs41_walk_client_list(struct nfs_client *new,
 698			   struct nfs_client **result,
 699			   struct rpc_cred *cred)
 700{
 701	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 702	struct nfs_client *pos, *prev = NULL;
 703	int status = -NFS4ERR_STALE_CLIENTID;
 704
 705	spin_lock(&nn->nfs_client_lock);
 706	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 707
 708		if (pos == new)
 709			goto found;
 710
 711		status = nfs4_match_client(pos, new, &prev, nn);
 712		if (status < 0)
 713			goto out;
 714		if (status != 0)
 715			continue;
 716
 717		/*
 718		 * Note that session trunking is just a special subcase of
 719		 * client id trunking. In either case, we want to fall back
 720		 * to using the existing nfs_client.
 721		 */
 722		if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
 723						     new->cl_serverowner))
 724			continue;
 725
 726found:
 727		refcount_inc(&pos->cl_count);
 728		*result = pos;
 729		status = 0;
 730		break;
 731	}
 732
 733out:
 734	spin_unlock(&nn->nfs_client_lock);
 735	nfs_put_client(prev);
 736	return status;
 737}
 738#endif	/* CONFIG_NFS_V4_1 */
 739
 740static void nfs4_destroy_server(struct nfs_server *server)
 741{
 
 
 742	nfs_server_return_all_delegations(server);
 743	unset_pnfs_layoutdriver(server);
 744	nfs4_purge_state_owners(server);
 
 745}
 746
 747/*
 748 * NFSv4.0 callback thread helper
 749 *
 750 * Find a client by callback identifier
 751 */
 752struct nfs_client *
 753nfs4_find_client_ident(struct net *net, int cb_ident)
 754{
 755	struct nfs_client *clp;
 756	struct nfs_net *nn = net_generic(net, nfs_net_id);
 757
 758	spin_lock(&nn->nfs_client_lock);
 759	clp = idr_find(&nn->cb_ident_idr, cb_ident);
 760	if (clp)
 761		refcount_inc(&clp->cl_count);
 762	spin_unlock(&nn->nfs_client_lock);
 763	return clp;
 764}
 765
 766#if defined(CONFIG_NFS_V4_1)
 767/* Common match routine for v4.0 and v4.1 callback services */
 768static bool nfs4_cb_match_client(const struct sockaddr *addr,
 769		struct nfs_client *clp, u32 minorversion)
 770{
 771	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 772
 773	/* Don't match clients that failed to initialise */
 774	if (!(clp->cl_cons_state == NFS_CS_READY ||
 775	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
 776		return false;
 777
 778	smp_rmb();
 779
 780	/* Match the version and minorversion */
 781	if (clp->rpc_ops->version != 4 ||
 782	    clp->cl_minorversion != minorversion)
 783		return false;
 784
 785	/* Match only the IP address, not the port number */
 786	return rpc_cmp_addr(addr, clap);
 787}
 788
 789/*
 790 * NFSv4.1 callback thread helper
 791 * For CB_COMPOUND calls, find a client by IP address, protocol version,
 792 * minorversion, and sessionID
 793 *
 794 * Returns NULL if no such client
 795 */
 796struct nfs_client *
 797nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 798			   struct nfs4_sessionid *sid, u32 minorversion)
 799{
 800	struct nfs_client *clp;
 801	struct nfs_net *nn = net_generic(net, nfs_net_id);
 802
 803	spin_lock(&nn->nfs_client_lock);
 804	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 805		if (!nfs4_cb_match_client(addr, clp, minorversion))
 806			continue;
 807
 808		if (!nfs4_has_session(clp))
 809			continue;
 810
 811		/* Match sessionid*/
 812		if (memcmp(clp->cl_session->sess_id.data,
 813		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 814			continue;
 815
 816		refcount_inc(&clp->cl_count);
 817		spin_unlock(&nn->nfs_client_lock);
 818		return clp;
 819	}
 820	spin_unlock(&nn->nfs_client_lock);
 821	return NULL;
 822}
 823
 824#else /* CONFIG_NFS_V4_1 */
 825
 826struct nfs_client *
 827nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 828			   struct nfs4_sessionid *sid, u32 minorversion)
 829{
 830	return NULL;
 831}
 832#endif /* CONFIG_NFS_V4_1 */
 833
 834/*
 835 * Set up an NFS4 client
 836 */
 837static int nfs4_set_client(struct nfs_server *server,
 838		const char *hostname,
 839		const struct sockaddr *addr,
 840		const size_t addrlen,
 841		const char *ip_addr,
 842		int proto, const struct rpc_timeout *timeparms,
 843		u32 minorversion, struct net *net)
 
 844{
 845	struct nfs_client_initdata cl_init = {
 846		.hostname = hostname,
 847		.addr = addr,
 848		.addrlen = addrlen,
 849		.ip_addr = ip_addr,
 850		.nfs_mod = &nfs_v4,
 851		.proto = proto,
 852		.minorversion = minorversion,
 853		.net = net,
 854		.timeparms = timeparms,
 
 855	};
 856	struct nfs_client *clp;
 857
 
 
 
 
 
 858	if (server->flags & NFS_MOUNT_NORESVPORT)
 859		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 860	if (server->options & NFS_OPTION_MIGRATION)
 861		set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 862	if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
 863		set_bit(NFS_CS_TSM_POSSIBLE, &cl_init.init_flags);
 864	server->port = rpc_get_port(addr);
 865
 866	/* Allocate or find a client reference we can use */
 867	clp = nfs_get_client(&cl_init);
 868	if (IS_ERR(clp))
 869		return PTR_ERR(clp);
 870
 871	if (server->nfs_client == clp) {
 872		nfs_put_client(clp);
 873		return -ELOOP;
 874	}
 875
 876	/*
 877	 * Query for the lease time on clientid setup or renewal
 878	 *
 879	 * Note that this will be set on nfs_clients that were created
 880	 * only for the DS role and did not set this bit, but now will
 881	 * serve a dual role.
 882	 */
 883	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 884
 885	server->nfs_client = clp;
 886	return 0;
 887}
 888
 889/*
 890 * Set up a pNFS Data Server client.
 891 *
 892 * Return any existing nfs_client that matches server address,port,version
 893 * and minorversion.
 894 *
 895 * For a new nfs_client, use a soft mount (default), a low retrans and a
 896 * low timeout interval so that if a connection is lost, we retry through
 897 * the MDS.
 898 */
 899struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
 900		const struct sockaddr *ds_addr, int ds_addrlen,
 901		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
 902		u32 minor_version)
 903{
 904	struct rpc_timeout ds_timeout;
 905	struct nfs_client *mds_clp = mds_srv->nfs_client;
 906	struct nfs_client_initdata cl_init = {
 907		.addr = ds_addr,
 908		.addrlen = ds_addrlen,
 909		.nodename = mds_clp->cl_rpcclient->cl_nodename,
 910		.ip_addr = mds_clp->cl_ipaddr,
 911		.nfs_mod = &nfs_v4,
 912		.proto = ds_proto,
 913		.minorversion = minor_version,
 914		.net = mds_clp->cl_net,
 915		.timeparms = &ds_timeout,
 
 916	};
 917	char buf[INET6_ADDRSTRLEN + 1];
 918
 919	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
 920		return ERR_PTR(-EINVAL);
 921	cl_init.hostname = buf;
 922
 
 
 
 923	if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
 924		__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 925
 926	/*
 927	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 928	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 929	 * (section 13.1 RFC 5661).
 930	 */
 931	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 932	return nfs_get_client(&cl_init);
 933}
 934EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
 935
 936/*
 937 * Session has been established, and the client marked ready.
 938 * Set the mount rsize and wsize with negotiated fore channel
 939 * attributes which will be bound checked in nfs_server_set_fsinfo.
 940 */
 941static void nfs4_session_set_rwsize(struct nfs_server *server)
 942{
 943#ifdef CONFIG_NFS_V4_1
 944	struct nfs4_session *sess;
 945	u32 server_resp_sz;
 946	u32 server_rqst_sz;
 947
 948	if (!nfs4_has_session(server->nfs_client))
 949		return;
 950	sess = server->nfs_client->cl_session;
 951	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
 952	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
 953
 954	if (!server->rsize || server->rsize > server_resp_sz)
 
 
 955		server->rsize = server_resp_sz;
 956	if (!server->wsize || server->wsize > server_rqst_sz)
 957		server->wsize = server_rqst_sz;
 958#endif /* CONFIG_NFS_V4_1 */
 959}
 960
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 961static int nfs4_server_common_setup(struct nfs_server *server,
 962		struct nfs_fh *mntfh, bool auth_probe)
 963{
 964	struct nfs_fattr *fattr;
 965	int error;
 966
 967	/* data servers support only a subset of NFSv4.1 */
 968	if (is_ds_only_client(server->nfs_client))
 969		return -EPROTONOSUPPORT;
 970
 971	fattr = nfs_alloc_fattr();
 972	if (fattr == NULL)
 973		return -ENOMEM;
 974
 975	/* We must ensure the session is initialised first */
 976	error = nfs4_init_session(server->nfs_client);
 977	if (error < 0)
 978		goto out;
 979
 980	/* Set the basic capabilities */
 981	server->caps |= server->nfs_client->cl_mvops->init_caps;
 982	if (server->flags & NFS_MOUNT_NORDIRPLUS)
 983			server->caps &= ~NFS_CAP_READDIRPLUS;
 
 
 984	/*
 985	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
 986	 * authentication.
 987	 */
 988	if (nfs4_disable_idmapping &&
 989			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
 990		server->caps |= NFS_CAP_UIDGID_NOMAP;
 991
 992
 993	/* Probe the root fh to retrieve its FSID and filehandle */
 994	error = nfs4_get_rootfh(server, mntfh, auth_probe);
 995	if (error < 0)
 996		goto out;
 997
 998	dprintk("Server FSID: %llx:%llx\n",
 999			(unsigned long long) server->fsid.major,
1000			(unsigned long long) server->fsid.minor);
1001	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1002
1003	nfs4_session_set_rwsize(server);
1004
1005	error = nfs_probe_fsinfo(server, mntfh, fattr);
1006	if (error < 0)
1007		goto out;
1008
 
 
 
1009	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1010		server->namelen = NFS4_MAXNAMLEN;
1011
1012	nfs_server_insert_lists(server);
1013	server->mount_time = jiffies;
1014	server->destroy = nfs4_destroy_server;
1015out:
1016	nfs_free_fattr(fattr);
1017	return error;
1018}
1019
1020/*
1021 * Create a version 4 volume record
1022 */
1023static int nfs4_init_server(struct nfs_server *server,
1024		struct nfs_parsed_mount_data *data)
1025{
 
1026	struct rpc_timeout timeparms;
1027	int error;
1028
1029	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1030			data->timeo, data->retrans);
1031
1032	/* Initialise the client representation from the mount data */
1033	server->flags = data->flags;
1034	server->options = data->options;
1035	server->auth_info = data->auth_info;
1036
1037	/* Use the first specified auth flavor. If this flavor isn't
1038	 * allowed by the server, use the SECINFO path to try the
1039	 * other specified flavors */
1040	if (data->auth_info.flavor_len >= 1)
1041		data->selected_flavor = data->auth_info.flavors[0];
1042	else
1043		data->selected_flavor = RPC_AUTH_UNIX;
1044
1045	/* Get a client record */
1046	error = nfs4_set_client(server,
1047			data->nfs_server.hostname,
1048			(const struct sockaddr *)&data->nfs_server.address,
1049			data->nfs_server.addrlen,
1050			data->client_address,
1051			data->nfs_server.protocol,
1052			&timeparms,
1053			data->minorversion,
1054			data->net);
 
1055	if (error < 0)
1056		return error;
1057
1058	if (data->rsize)
1059		server->rsize = nfs_block_size(data->rsize, NULL);
1060	if (data->wsize)
1061		server->wsize = nfs_block_size(data->wsize, NULL);
1062
1063	server->acregmin = data->acregmin * HZ;
1064	server->acregmax = data->acregmax * HZ;
1065	server->acdirmin = data->acdirmin * HZ;
1066	server->acdirmax = data->acdirmax * HZ;
1067	server->port     = data->nfs_server.port;
1068
1069	return nfs_init_server_rpcclient(server, &timeparms,
1070					 data->selected_flavor);
1071}
1072
1073/*
1074 * Create a version 4 volume record
1075 * - keyed on server and FSID
1076 */
1077/*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1078				      struct nfs_fh *mntfh)*/
1079struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1080				      struct nfs_subversion *nfs_mod)
1081{
 
1082	struct nfs_server *server;
1083	bool auth_probe;
1084	int error;
1085
1086	server = nfs_alloc_server();
1087	if (!server)
1088		return ERR_PTR(-ENOMEM);
1089
1090	auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
 
 
1091
1092	/* set up the general RPC client */
1093	error = nfs4_init_server(server, mount_info->parsed);
1094	if (error < 0)
1095		goto error;
1096
1097	error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1098	if (error < 0)
1099		goto error;
1100
1101	return server;
1102
1103error:
1104	nfs_free_server(server);
1105	return ERR_PTR(error);
1106}
1107
1108/*
1109 * Create an NFS4 referral server record
1110 */
1111struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1112					       struct nfs_fh *mntfh)
1113{
 
1114	struct nfs_client *parent_client;
1115	struct nfs_server *server, *parent_server;
1116	bool auth_probe;
1117	int error;
1118
1119	server = nfs_alloc_server();
1120	if (!server)
1121		return ERR_PTR(-ENOMEM);
1122
1123	parent_server = NFS_SB(data->sb);
1124	parent_client = parent_server->nfs_client;
1125
 
 
1126	/* Initialise the client representation from the parent server */
1127	nfs_server_copy_userdata(server, parent_server);
1128
1129	/* Get a client representation */
1130#ifdef CONFIG_SUNRPC_XPRT_RDMA
1131	rpc_set_port(data->addr, NFS_RDMA_PORT);
1132	error = nfs4_set_client(server, data->hostname,
1133				data->addr,
1134				data->addrlen,
 
1135				parent_client->cl_ipaddr,
1136				XPRT_TRANSPORT_RDMA,
1137				parent_server->client->cl_timeout,
1138				parent_client->cl_mvops->minor_version,
 
1139				parent_client->cl_net);
1140	if (!error)
1141		goto init_server;
1142#endif	/* CONFIG_SUNRPC_XPRT_RDMA */
1143
1144	rpc_set_port(data->addr, NFS_PORT);
1145	error = nfs4_set_client(server, data->hostname,
1146				data->addr,
1147				data->addrlen,
 
1148				parent_client->cl_ipaddr,
1149				XPRT_TRANSPORT_TCP,
1150				parent_server->client->cl_timeout,
1151				parent_client->cl_mvops->minor_version,
 
1152				parent_client->cl_net);
1153	if (error < 0)
1154		goto error;
1155
1156#ifdef CONFIG_SUNRPC_XPRT_RDMA
1157init_server:
1158#endif
1159	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
 
1160	if (error < 0)
1161		goto error;
1162
1163	auth_probe = parent_server->auth_info.flavor_len < 1;
1164
1165	error = nfs4_server_common_setup(server, mntfh, auth_probe);
1166	if (error < 0)
1167		goto error;
1168
1169	return server;
1170
1171error:
1172	nfs_free_server(server);
1173	return ERR_PTR(error);
1174}
1175
1176/*
1177 * Grab the destination's particulars, including lease expiry time.
1178 *
1179 * Returns zero if probe succeeded and retrieved FSID matches the FSID
1180 * we have cached.
1181 */
1182static int nfs_probe_destination(struct nfs_server *server)
1183{
1184	struct inode *inode = d_inode(server->super->s_root);
1185	struct nfs_fattr *fattr;
1186	int error;
1187
1188	fattr = nfs_alloc_fattr();
1189	if (fattr == NULL)
1190		return -ENOMEM;
1191
1192	/* Sanity: the probe won't work if the destination server
1193	 * does not recognize the migrated FH. */
1194	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1195
1196	nfs_free_fattr(fattr);
1197	return error;
1198}
1199
1200/**
1201 * nfs4_update_server - Move an nfs_server to a different nfs_client
1202 *
1203 * @server: represents FSID to be moved
1204 * @hostname: new end-point's hostname
1205 * @sap: new end-point's socket address
1206 * @salen: size of "sap"
1207 * @net: net namespace
1208 *
1209 * The nfs_server must be quiescent before this function is invoked.
1210 * Either its session is drained (NFSv4.1+), or its transport is
1211 * plugged and drained (NFSv4.0).
1212 *
1213 * Returns zero on success, or a negative errno value.
1214 */
1215int nfs4_update_server(struct nfs_server *server, const char *hostname,
1216		       struct sockaddr *sap, size_t salen, struct net *net)
1217{
1218	struct nfs_client *clp = server->nfs_client;
1219	struct rpc_clnt *clnt = server->client;
1220	struct xprt_create xargs = {
1221		.ident		= clp->cl_proto,
1222		.net		= net,
1223		.dstaddr	= sap,
1224		.addrlen	= salen,
1225		.servername	= hostname,
1226	};
1227	char buf[INET6_ADDRSTRLEN + 1];
1228	struct sockaddr_storage address;
1229	struct sockaddr *localaddr = (struct sockaddr *)&address;
1230	int error;
1231
1232	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1233	if (error != 0)
1234		return error;
1235
1236	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1237	if (error != 0)
1238		return error;
1239
1240	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
1241		return -EAFNOSUPPORT;
1242
1243	nfs_server_remove_lists(server);
1244	set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1245	error = nfs4_set_client(server, hostname, sap, salen, buf,
1246				clp->cl_proto, clnt->cl_timeout,
1247				clp->cl_minorversion, net);
 
1248	clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1249	if (error != 0) {
1250		nfs_server_insert_lists(server);
1251		return error;
1252	}
1253	nfs_put_client(clp);
1254
1255	if (server->nfs_client->cl_hostname == NULL)
1256		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1257	nfs_server_insert_lists(server);
1258
1259	return nfs_probe_destination(server);
1260}
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}