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   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	return clp;
 203
 204error:
 205	nfs_free_client(clp);
 206	return ERR_PTR(err);
 207}
 208
 209/*
 210 * Destroy the NFS4 callback service
 211 */
 212static void nfs4_destroy_callback(struct nfs_client *clp)
 213{
 214	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 215		nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 216}
 217
 218static void nfs4_shutdown_client(struct nfs_client *clp)
 219{
 220	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 221		nfs4_kill_renewd(clp);
 222	clp->cl_mvops->shutdown_client(clp);
 223	nfs4_destroy_callback(clp);
 224	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 225		nfs_idmap_delete(clp);
 226
 227	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 228	kfree(clp->cl_serverowner);
 229	kfree(clp->cl_serverscope);
 230	kfree(clp->cl_implid);
 231	kfree(clp->cl_owner_id);
 232}
 233
 234void nfs4_free_client(struct nfs_client *clp)
 235{
 236	nfs4_shutdown_client(clp);
 237	nfs_free_client(clp);
 238}
 239
 240/*
 241 * Initialize the NFS4 callback service
 242 */
 243static int nfs4_init_callback(struct nfs_client *clp)
 244{
 245	struct rpc_xprt *xprt;
 246	int error;
 247
 248	xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
 249
 250	if (nfs4_has_session(clp)) {
 251		error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
 252		if (error < 0)
 253			return error;
 254	}
 255
 256	error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
 257	if (error < 0) {
 258		dprintk("%s: failed to start callback. Error = %d\n",
 259			__func__, error);
 260		return error;
 261	}
 262	__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 263
 264	return 0;
 265}
 266
 267/**
 268 * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
 269 * @clp - nfs_client to initialize
 270 *
 271 * Returns zero on success, or a negative errno if some error occurred.
 272 */
 273int nfs40_init_client(struct nfs_client *clp)
 274{
 275	struct nfs4_slot_table *tbl;
 276	int ret;
 277
 278	tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
 279	if (tbl == NULL)
 280		return -ENOMEM;
 281
 282	ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
 283					"NFSv4.0 transport Slot table");
 284	if (ret) {
 285		kfree(tbl);
 286		return ret;
 287	}
 288
 289	clp->cl_slot_tbl = tbl;
 290	return 0;
 291}
 292
 293#if defined(CONFIG_NFS_V4_1)
 294
 295/**
 296 * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 297 * @clp - nfs_client to initialize
 298 *
 299 * Returns zero on success, or a negative errno if some error occurred.
 300 */
 301int nfs41_init_client(struct nfs_client *clp)
 302{
 303	struct nfs4_session *session = NULL;
 304
 305	/*
 306	 * Create the session and mark it expired.
 307	 * When a SEQUENCE operation encounters the expired session
 308	 * it will do session recovery to initialize it.
 309	 */
 310	session = nfs4_alloc_session(clp);
 311	if (!session)
 312		return -ENOMEM;
 313
 314	clp->cl_session = session;
 315
 316	/*
 317	 * The create session reply races with the server back
 318	 * channel probe. Mark the client NFS_CS_SESSION_INITING
 319	 * so that the client back channel can find the
 320	 * nfs_client struct
 321	 */
 322	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 323	return 0;
 324}
 325
 326#endif	/* CONFIG_NFS_V4_1 */
 327
 328/*
 329 * Initialize the minor version specific parts of an NFS4 client record
 330 */
 331static int nfs4_init_client_minor_version(struct nfs_client *clp)
 332{
 333	int ret;
 334
 335	ret = clp->cl_mvops->init_client(clp);
 336	if (ret)
 337		return ret;
 338	return nfs4_init_callback(clp);
 339}
 340
 341/**
 342 * nfs4_init_client - Initialise an NFS4 client record
 343 *
 344 * @clp: nfs_client to initialise
 345 * @timeparms: timeout parameters for underlying RPC transport
 346 * @ip_addr: callback IP address in presentation format
 347 * @authflavor: authentication flavor for underlying RPC transport
 348 *
 349 * Returns pointer to an NFS client, or an ERR_PTR value.
 350 */
 351struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 352				    const struct rpc_timeout *timeparms,
 353				    const char *ip_addr)
 354{
 355	char buf[INET6_ADDRSTRLEN + 1];
 356	struct nfs_client *old;
 357	int error;
 358
 359	if (clp->cl_cons_state == NFS_CS_READY) {
 360		/* the client is initialised already */
 361		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
 362		return clp;
 363	}
 364
 365	/* Check NFS protocol revision and initialize RPC op vector */
 366	clp->rpc_ops = &nfs_v4_clientops;
 367
 368	if (clp->cl_minorversion != 0)
 369		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 370	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
 371	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 372
 373	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_GSS_KRB5I);
 374	if (error == -EINVAL)
 375		error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
 376	if (error < 0)
 377		goto error;
 378
 379	/* If no clientaddr= option was specified, find a usable cb address */
 380	if (ip_addr == NULL) {
 381		struct sockaddr_storage cb_addr;
 382		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
 383
 384		error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
 385		if (error < 0)
 386			goto error;
 387		error = rpc_ntop(sap, buf, sizeof(buf));
 388		if (error < 0)
 389			goto error;
 390		ip_addr = (const char *)buf;
 391	}
 392	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 393
 394	error = nfs_idmap_new(clp);
 395	if (error < 0) {
 396		dprintk("%s: failed to create idmapper. Error = %d\n",
 397			__func__, error);
 398		goto error;
 399	}
 400	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 401
 402	error = nfs4_init_client_minor_version(clp);
 403	if (error < 0)
 404		goto error;
 405
 406	if (!nfs4_has_session(clp))
 407		nfs_mark_client_ready(clp, NFS_CS_READY);
 408
 409	error = nfs4_discover_server_trunking(clp, &old);
 410	if (error < 0)
 411		goto error;
 412
 413	if (clp != old)
 414		clp->cl_preserve_clid = true;
 415	nfs_put_client(clp);
 416	return old;
 417
 418error:
 419	nfs_mark_client_ready(clp, error);
 420	nfs_put_client(clp);
 421	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
 422	return ERR_PTR(error);
 423}
 424
 425/*
 426 * SETCLIENTID just did a callback update with the callback ident in
 427 * "drop," but server trunking discovery claims "drop" and "keep" are
 428 * actually the same server.  Swap the callback IDs so that "keep"
 429 * will continue to use the callback ident the server now knows about,
 430 * and so that "keep"'s original callback ident is destroyed when
 431 * "drop" is freed.
 432 */
 433static void nfs4_swap_callback_idents(struct nfs_client *keep,
 434				      struct nfs_client *drop)
 435{
 436	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
 437	unsigned int save = keep->cl_cb_ident;
 438
 439	if (keep->cl_cb_ident == drop->cl_cb_ident)
 440		return;
 441
 442	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
 443		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
 444
 445	spin_lock(&nn->nfs_client_lock);
 446
 447	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
 448	keep->cl_cb_ident = drop->cl_cb_ident;
 449
 450	idr_replace(&nn->cb_ident_idr, drop, save);
 451	drop->cl_cb_ident = save;
 452
 453	spin_unlock(&nn->nfs_client_lock);
 454}
 455
 456static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
 457		const struct nfs_client *clp2)
 458{
 459	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
 460		return true;
 461	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
 462}
 463
 464/**
 465 * nfs40_walk_client_list - Find server that recognizes a client ID
 466 *
 467 * @new: nfs_client with client ID to test
 468 * @result: OUT: found nfs_client, or new
 469 * @cred: credential to use for trunking test
 470 *
 471 * Returns zero, a negative errno, or a negative NFS4ERR status.
 472 * If zero is returned, an nfs_client pointer is planted in "result."
 473 *
 474 * NB: nfs40_walk_client_list() relies on the new nfs_client being
 475 *     the last nfs_client on the list.
 476 */
 477int nfs40_walk_client_list(struct nfs_client *new,
 478			   struct nfs_client **result,
 479			   struct rpc_cred *cred)
 480{
 481	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 482	struct nfs_client *pos, *prev = NULL;
 483	struct nfs4_setclientid_res clid = {
 484		.clientid	= new->cl_clientid,
 485		.confirm	= new->cl_confirm,
 486	};
 487	int status = -NFS4ERR_STALE_CLIENTID;
 488
 489	spin_lock(&nn->nfs_client_lock);
 490	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 491
 492		if (pos->rpc_ops != new->rpc_ops)
 493			continue;
 494
 495		if (pos->cl_minorversion != new->cl_minorversion)
 496			continue;
 497
 498		/* If "pos" isn't marked ready, we can't trust the
 499		 * remaining fields in "pos" */
 500		if (pos->cl_cons_state > NFS_CS_READY) {
 501			atomic_inc(&pos->cl_count);
 502			spin_unlock(&nn->nfs_client_lock);
 503
 504			nfs_put_client(prev);
 505			prev = pos;
 506
 507			status = nfs_wait_client_init_complete(pos);
 508			if (status < 0)
 509				goto out;
 510			status = -NFS4ERR_STALE_CLIENTID;
 511			spin_lock(&nn->nfs_client_lock);
 512		}
 513		if (pos->cl_cons_state != NFS_CS_READY)
 514			continue;
 515
 516		if (pos->cl_clientid != new->cl_clientid)
 517			continue;
 518
 519		if (!nfs4_match_client_owner_id(pos, new))
 520			continue;
 521
 522		atomic_inc(&pos->cl_count);
 523		spin_unlock(&nn->nfs_client_lock);
 524
 525		nfs_put_client(prev);
 526		prev = pos;
 527
 528		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 529		switch (status) {
 530		case -NFS4ERR_STALE_CLIENTID:
 531			break;
 532		case 0:
 533			nfs4_swap_callback_idents(pos, new);
 534
 535			prev = NULL;
 536			*result = pos;
 537			dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
 538				__func__, pos, atomic_read(&pos->cl_count));
 539			goto out;
 540		case -ERESTARTSYS:
 541		case -ETIMEDOUT:
 542			/* The callback path may have been inadvertently
 543			 * changed. Schedule recovery!
 544			 */
 545			nfs4_schedule_path_down_recovery(pos);
 546		default:
 547			goto out;
 548		}
 549
 550		spin_lock(&nn->nfs_client_lock);
 551	}
 552	spin_unlock(&nn->nfs_client_lock);
 553
 554	/* No match found. The server lost our clientid */
 555out:
 556	nfs_put_client(prev);
 557	dprintk("NFS: <-- %s status = %d\n", __func__, status);
 558	return status;
 559}
 560
 561#ifdef CONFIG_NFS_V4_1
 562/*
 563 * Returns true if the client IDs match
 564 */
 565static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b)
 566{
 567	if (a->cl_clientid != b->cl_clientid) {
 568		dprintk("NFS: --> %s client ID %llx does not match %llx\n",
 569			__func__, a->cl_clientid, b->cl_clientid);
 570		return false;
 571	}
 572	dprintk("NFS: --> %s client ID %llx matches %llx\n",
 573		__func__, a->cl_clientid, b->cl_clientid);
 574	return true;
 575}
 576
 577/*
 578 * Returns true if the server major ids match
 579 */
 580static bool
 581nfs4_check_clientid_trunking(struct nfs_client *a, struct nfs_client *b)
 582{
 583	struct nfs41_server_owner *o1 = a->cl_serverowner;
 584	struct nfs41_server_owner *o2 = b->cl_serverowner;
 585
 586	if (o1->major_id_sz != o2->major_id_sz)
 587		goto out_major_mismatch;
 588	if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0)
 589		goto out_major_mismatch;
 590
 591	dprintk("NFS: --> %s server owners match\n", __func__);
 592	return true;
 593
 594out_major_mismatch:
 595	dprintk("NFS: --> %s server owner major IDs do not match\n",
 596		__func__);
 597	return false;
 598}
 599
 600/**
 601 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 602 *
 603 * @new: nfs_client with client ID to test
 604 * @result: OUT: found nfs_client, or new
 605 * @cred: credential to use for trunking test
 606 *
 607 * Returns zero, a negative errno, or a negative NFS4ERR status.
 608 * If zero is returned, an nfs_client pointer is planted in "result."
 609 *
 610 * NB: nfs41_walk_client_list() relies on the new nfs_client being
 611 *     the last nfs_client on the list.
 612 */
 613int nfs41_walk_client_list(struct nfs_client *new,
 614			   struct nfs_client **result,
 615			   struct rpc_cred *cred)
 616{
 617	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 618	struct nfs_client *pos, *prev = NULL;
 619	int status = -NFS4ERR_STALE_CLIENTID;
 620
 621	spin_lock(&nn->nfs_client_lock);
 622	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 623
 624		if (pos == new)
 625			goto found;
 626
 627		if (pos->rpc_ops != new->rpc_ops)
 628			continue;
 629
 630		if (pos->cl_minorversion != new->cl_minorversion)
 631			continue;
 632
 633		/* If "pos" isn't marked ready, we can't trust the
 634		 * remaining fields in "pos", especially the client
 635		 * ID and serverowner fields.  Wait for CREATE_SESSION
 636		 * to finish. */
 637		if (pos->cl_cons_state > NFS_CS_READY) {
 638			atomic_inc(&pos->cl_count);
 639			spin_unlock(&nn->nfs_client_lock);
 640
 641			nfs_put_client(prev);
 642			prev = pos;
 643
 644			status = nfs_wait_client_init_complete(pos);
 645			spin_lock(&nn->nfs_client_lock);
 646			if (status < 0)
 647				break;
 648			status = -NFS4ERR_STALE_CLIENTID;
 649		}
 650		if (pos->cl_cons_state != NFS_CS_READY)
 651			continue;
 652
 653		if (!nfs4_match_clientids(pos, new))
 654			continue;
 655
 656		/*
 657		 * Note that session trunking is just a special subcase of
 658		 * client id trunking. In either case, we want to fall back
 659		 * to using the existing nfs_client.
 660		 */
 661		if (!nfs4_check_clientid_trunking(pos, new))
 662			continue;
 663
 664		/* Unlike NFSv4.0, we know that NFSv4.1 always uses the
 665		 * uniform string, however someone might switch the
 666		 * uniquifier string on us.
 667		 */
 668		if (!nfs4_match_client_owner_id(pos, new))
 669			continue;
 670found:
 671		atomic_inc(&pos->cl_count);
 672		*result = pos;
 673		status = 0;
 674		dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
 675			__func__, pos, atomic_read(&pos->cl_count));
 676		break;
 677	}
 678
 679	spin_unlock(&nn->nfs_client_lock);
 680	dprintk("NFS: <-- %s status = %d\n", __func__, status);
 681	nfs_put_client(prev);
 682	return status;
 683}
 684#endif	/* CONFIG_NFS_V4_1 */
 685
 686static void nfs4_destroy_server(struct nfs_server *server)
 687{
 688	nfs_server_return_all_delegations(server);
 689	unset_pnfs_layoutdriver(server);
 690	nfs4_purge_state_owners(server);
 691}
 692
 693/*
 694 * NFSv4.0 callback thread helper
 695 *
 696 * Find a client by callback identifier
 697 */
 698struct nfs_client *
 699nfs4_find_client_ident(struct net *net, int cb_ident)
 700{
 701	struct nfs_client *clp;
 702	struct nfs_net *nn = net_generic(net, nfs_net_id);
 703
 704	spin_lock(&nn->nfs_client_lock);
 705	clp = idr_find(&nn->cb_ident_idr, cb_ident);
 706	if (clp)
 707		atomic_inc(&clp->cl_count);
 708	spin_unlock(&nn->nfs_client_lock);
 709	return clp;
 710}
 711
 712#if defined(CONFIG_NFS_V4_1)
 713/* Common match routine for v4.0 and v4.1 callback services */
 714static bool nfs4_cb_match_client(const struct sockaddr *addr,
 715		struct nfs_client *clp, u32 minorversion)
 716{
 717	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 718
 719	/* Don't match clients that failed to initialise */
 720	if (!(clp->cl_cons_state == NFS_CS_READY ||
 721	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
 722		return false;
 723
 724	smp_rmb();
 725
 726	/* Match the version and minorversion */
 727	if (clp->rpc_ops->version != 4 ||
 728	    clp->cl_minorversion != minorversion)
 729		return false;
 730
 731	/* Match only the IP address, not the port number */
 732	return rpc_cmp_addr(addr, clap);
 733}
 734
 735/*
 736 * NFSv4.1 callback thread helper
 737 * For CB_COMPOUND calls, find a client by IP address, protocol version,
 738 * minorversion, and sessionID
 739 *
 740 * Returns NULL if no such client
 741 */
 742struct nfs_client *
 743nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 744			   struct nfs4_sessionid *sid, u32 minorversion)
 745{
 746	struct nfs_client *clp;
 747	struct nfs_net *nn = net_generic(net, nfs_net_id);
 748
 749	spin_lock(&nn->nfs_client_lock);
 750	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 751		if (nfs4_cb_match_client(addr, clp, minorversion) == false)
 752			continue;
 753
 754		if (!nfs4_has_session(clp))
 755			continue;
 756
 757		/* Match sessionid*/
 758		if (memcmp(clp->cl_session->sess_id.data,
 759		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 760			continue;
 761
 762		atomic_inc(&clp->cl_count);
 763		spin_unlock(&nn->nfs_client_lock);
 764		return clp;
 765	}
 766	spin_unlock(&nn->nfs_client_lock);
 767	return NULL;
 768}
 769
 770#else /* CONFIG_NFS_V4_1 */
 771
 772struct nfs_client *
 773nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 774			   struct nfs4_sessionid *sid, u32 minorversion)
 775{
 776	return NULL;
 777}
 778#endif /* CONFIG_NFS_V4_1 */
 779
 780/*
 781 * Set up an NFS4 client
 782 */
 783static int nfs4_set_client(struct nfs_server *server,
 784		const char *hostname,
 785		const struct sockaddr *addr,
 786		const size_t addrlen,
 787		const char *ip_addr,
 788		rpc_authflavor_t authflavour,
 789		int proto, const struct rpc_timeout *timeparms,
 790		u32 minorversion, struct net *net)
 791{
 792	struct nfs_client_initdata cl_init = {
 793		.hostname = hostname,
 794		.addr = addr,
 795		.addrlen = addrlen,
 796		.nfs_mod = &nfs_v4,
 797		.proto = proto,
 798		.minorversion = minorversion,
 799		.net = net,
 800	};
 801	struct nfs_client *clp;
 802	int error;
 803
 804	dprintk("--> nfs4_set_client()\n");
 805
 806	if (server->flags & NFS_MOUNT_NORESVPORT)
 807		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 808	if (server->options & NFS_OPTION_MIGRATION)
 809		set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 810
 811	/* Allocate or find a client reference we can use */
 812	clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
 813	if (IS_ERR(clp)) {
 814		error = PTR_ERR(clp);
 815		goto error;
 816	}
 817
 818	/*
 819	 * Query for the lease time on clientid setup or renewal
 820	 *
 821	 * Note that this will be set on nfs_clients that were created
 822	 * only for the DS role and did not set this bit, but now will
 823	 * serve a dual role.
 824	 */
 825	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 826
 827	server->nfs_client = clp;
 828	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
 829	return 0;
 830error:
 831	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
 832	return error;
 833}
 834
 835/*
 836 * Set up a pNFS Data Server client.
 837 *
 838 * Return any existing nfs_client that matches server address,port,version
 839 * and minorversion.
 840 *
 841 * For a new nfs_client, use a soft mount (default), a low retrans and a
 842 * low timeout interval so that if a connection is lost, we retry through
 843 * the MDS.
 844 */
 845struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
 846		const struct sockaddr *ds_addr, int ds_addrlen,
 847		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
 848		u32 minor_version, rpc_authflavor_t au_flavor)
 849{
 850	struct nfs_client_initdata cl_init = {
 851		.addr = ds_addr,
 852		.addrlen = ds_addrlen,
 853		.nfs_mod = &nfs_v4,
 854		.proto = ds_proto,
 855		.minorversion = minor_version,
 856		.net = mds_clp->cl_net,
 857	};
 858	struct rpc_timeout ds_timeout;
 859	struct nfs_client *clp;
 860	char buf[INET6_ADDRSTRLEN + 1];
 861
 862	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
 863		return ERR_PTR(-EINVAL);
 864	cl_init.hostname = buf;
 865
 866	/*
 867	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 868	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 869	 * (section 13.1 RFC 5661).
 870	 */
 871	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 872	clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
 873			     au_flavor);
 874
 875	dprintk("<-- %s %p\n", __func__, clp);
 876	return clp;
 877}
 878EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
 879
 880/*
 881 * Session has been established, and the client marked ready.
 882 * Set the mount rsize and wsize with negotiated fore channel
 883 * attributes which will be bound checked in nfs_server_set_fsinfo.
 884 */
 885static void nfs4_session_set_rwsize(struct nfs_server *server)
 886{
 887#ifdef CONFIG_NFS_V4_1
 888	struct nfs4_session *sess;
 889	u32 server_resp_sz;
 890	u32 server_rqst_sz;
 891
 892	if (!nfs4_has_session(server->nfs_client))
 893		return;
 894	sess = server->nfs_client->cl_session;
 895	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
 896	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
 897
 898	if (server->rsize > server_resp_sz)
 899		server->rsize = server_resp_sz;
 900	if (server->wsize > server_rqst_sz)
 901		server->wsize = server_rqst_sz;
 902#endif /* CONFIG_NFS_V4_1 */
 903}
 904
 905static int nfs4_server_common_setup(struct nfs_server *server,
 906		struct nfs_fh *mntfh, bool auth_probe)
 907{
 908	struct nfs_fattr *fattr;
 909	int error;
 910
 911	/* data servers support only a subset of NFSv4.1 */
 912	if (is_ds_only_client(server->nfs_client))
 913		return -EPROTONOSUPPORT;
 914
 915	fattr = nfs_alloc_fattr();
 916	if (fattr == NULL)
 917		return -ENOMEM;
 918
 919	/* We must ensure the session is initialised first */
 920	error = nfs4_init_session(server->nfs_client);
 921	if (error < 0)
 922		goto out;
 923
 924	/* Set the basic capabilities */
 925	server->caps |= server->nfs_client->cl_mvops->init_caps;
 926	if (server->flags & NFS_MOUNT_NORDIRPLUS)
 927			server->caps &= ~NFS_CAP_READDIRPLUS;
 928	/*
 929	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
 930	 * authentication.
 931	 */
 932	if (nfs4_disable_idmapping &&
 933			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
 934		server->caps |= NFS_CAP_UIDGID_NOMAP;
 935
 936
 937	/* Probe the root fh to retrieve its FSID and filehandle */
 938	error = nfs4_get_rootfh(server, mntfh, auth_probe);
 939	if (error < 0)
 940		goto out;
 941
 942	dprintk("Server FSID: %llx:%llx\n",
 943			(unsigned long long) server->fsid.major,
 944			(unsigned long long) server->fsid.minor);
 945	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
 946
 947	nfs4_session_set_rwsize(server);
 948
 949	error = nfs_probe_fsinfo(server, mntfh, fattr);
 950	if (error < 0)
 951		goto out;
 952
 953	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
 954		server->namelen = NFS4_MAXNAMLEN;
 955
 956	nfs_server_insert_lists(server);
 957	server->mount_time = jiffies;
 958	server->destroy = nfs4_destroy_server;
 959out:
 960	nfs_free_fattr(fattr);
 961	return error;
 962}
 963
 964/*
 965 * Create a version 4 volume record
 966 */
 967static int nfs4_init_server(struct nfs_server *server,
 968		struct nfs_parsed_mount_data *data)
 969{
 970	struct rpc_timeout timeparms;
 971	int error;
 972
 973	dprintk("--> nfs4_init_server()\n");
 974
 975	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 976			data->timeo, data->retrans);
 977
 978	/* Initialise the client representation from the mount data */
 979	server->flags = data->flags;
 980	server->options = data->options;
 981	server->auth_info = data->auth_info;
 982
 983	/* Use the first specified auth flavor. If this flavor isn't
 984	 * allowed by the server, use the SECINFO path to try the
 985	 * other specified flavors */
 986	if (data->auth_info.flavor_len >= 1)
 987		data->selected_flavor = data->auth_info.flavors[0];
 988	else
 989		data->selected_flavor = RPC_AUTH_UNIX;
 990
 991	/* Get a client record */
 992	error = nfs4_set_client(server,
 993			data->nfs_server.hostname,
 994			(const struct sockaddr *)&data->nfs_server.address,
 995			data->nfs_server.addrlen,
 996			data->client_address,
 997			data->selected_flavor,
 998			data->nfs_server.protocol,
 999			&timeparms,
1000			data->minorversion,
1001			data->net);
1002	if (error < 0)
1003		goto error;
1004
1005	if (data->rsize)
1006		server->rsize = nfs_block_size(data->rsize, NULL);
1007	if (data->wsize)
1008		server->wsize = nfs_block_size(data->wsize, NULL);
1009
1010	server->acregmin = data->acregmin * HZ;
1011	server->acregmax = data->acregmax * HZ;
1012	server->acdirmin = data->acdirmin * HZ;
1013	server->acdirmax = data->acdirmax * HZ;
1014
1015	server->port = data->nfs_server.port;
1016
1017	error = nfs_init_server_rpcclient(server, &timeparms,
1018					  data->selected_flavor);
1019
1020error:
1021	/* Done */
1022	dprintk("<-- nfs4_init_server() = %d\n", error);
1023	return error;
1024}
1025
1026/*
1027 * Create a version 4 volume record
1028 * - keyed on server and FSID
1029 */
1030/*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1031				      struct nfs_fh *mntfh)*/
1032struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1033				      struct nfs_subversion *nfs_mod)
1034{
1035	struct nfs_server *server;
1036	bool auth_probe;
1037	int error;
1038
1039	dprintk("--> nfs4_create_server()\n");
1040
1041	server = nfs_alloc_server();
1042	if (!server)
1043		return ERR_PTR(-ENOMEM);
1044
1045	auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1046
1047	/* set up the general RPC client */
1048	error = nfs4_init_server(server, mount_info->parsed);
1049	if (error < 0)
1050		goto error;
1051
1052	error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1053	if (error < 0)
1054		goto error;
1055
1056	dprintk("<-- nfs4_create_server() = %p\n", server);
1057	return server;
1058
1059error:
1060	nfs_free_server(server);
1061	dprintk("<-- nfs4_create_server() = error %d\n", error);
1062	return ERR_PTR(error);
1063}
1064
1065/*
1066 * Create an NFS4 referral server record
1067 */
1068struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1069					       struct nfs_fh *mntfh)
1070{
1071	struct nfs_client *parent_client;
1072	struct nfs_server *server, *parent_server;
1073	bool auth_probe;
1074	int error;
1075
1076	dprintk("--> nfs4_create_referral_server()\n");
1077
1078	server = nfs_alloc_server();
1079	if (!server)
1080		return ERR_PTR(-ENOMEM);
1081
1082	parent_server = NFS_SB(data->sb);
1083	parent_client = parent_server->nfs_client;
1084
1085	/* Initialise the client representation from the parent server */
1086	nfs_server_copy_userdata(server, parent_server);
1087
1088	/* Get a client representation.
1089	 * Note: NFSv4 always uses TCP, */
1090	error = nfs4_set_client(server, data->hostname,
1091				data->addr,
1092				data->addrlen,
1093				parent_client->cl_ipaddr,
1094				data->authflavor,
1095				rpc_protocol(parent_server->client),
1096				parent_server->client->cl_timeout,
1097				parent_client->cl_mvops->minor_version,
1098				parent_client->cl_net);
1099	if (error < 0)
1100		goto error;
1101
1102	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1103	if (error < 0)
1104		goto error;
1105
1106	auth_probe = parent_server->auth_info.flavor_len < 1;
1107
1108	error = nfs4_server_common_setup(server, mntfh, auth_probe);
1109	if (error < 0)
1110		goto error;
1111
1112	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1113	return server;
1114
1115error:
1116	nfs_free_server(server);
1117	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1118	return ERR_PTR(error);
1119}
1120
1121/*
1122 * Grab the destination's particulars, including lease expiry time.
1123 *
1124 * Returns zero if probe succeeded and retrieved FSID matches the FSID
1125 * we have cached.
1126 */
1127static int nfs_probe_destination(struct nfs_server *server)
1128{
1129	struct inode *inode = d_inode(server->super->s_root);
1130	struct nfs_fattr *fattr;
1131	int error;
1132
1133	fattr = nfs_alloc_fattr();
1134	if (fattr == NULL)
1135		return -ENOMEM;
1136
1137	/* Sanity: the probe won't work if the destination server
1138	 * does not recognize the migrated FH. */
1139	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1140
1141	nfs_free_fattr(fattr);
1142	return error;
1143}
1144
1145/**
1146 * nfs4_update_server - Move an nfs_server to a different nfs_client
1147 *
1148 * @server: represents FSID to be moved
1149 * @hostname: new end-point's hostname
1150 * @sap: new end-point's socket address
1151 * @salen: size of "sap"
1152 * @net: net namespace
1153 *
1154 * The nfs_server must be quiescent before this function is invoked.
1155 * Either its session is drained (NFSv4.1+), or its transport is
1156 * plugged and drained (NFSv4.0).
1157 *
1158 * Returns zero on success, or a negative errno value.
1159 */
1160int nfs4_update_server(struct nfs_server *server, const char *hostname,
1161		       struct sockaddr *sap, size_t salen, struct net *net)
1162{
1163	struct nfs_client *clp = server->nfs_client;
1164	struct rpc_clnt *clnt = server->client;
1165	struct xprt_create xargs = {
1166		.ident		= clp->cl_proto,
1167		.net		= net,
1168		.dstaddr	= sap,
1169		.addrlen	= salen,
1170		.servername	= hostname,
1171	};
1172	char buf[INET6_ADDRSTRLEN + 1];
1173	struct sockaddr_storage address;
1174	struct sockaddr *localaddr = (struct sockaddr *)&address;
1175	int error;
1176
1177	dprintk("--> %s: move FSID %llx:%llx to \"%s\")\n", __func__,
1178			(unsigned long long)server->fsid.major,
1179			(unsigned long long)server->fsid.minor,
1180			hostname);
1181
1182	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1183	if (error != 0) {
1184		dprintk("<-- %s(): rpc_switch_client_transport returned %d\n",
1185			__func__, error);
1186		goto out;
1187	}
1188
1189	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1190	if (error != 0) {
1191		dprintk("<-- %s(): rpc_localaddr returned %d\n",
1192			__func__, error);
1193		goto out;
1194	}
1195
1196	error = -EAFNOSUPPORT;
1197	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0) {
1198		dprintk("<-- %s(): rpc_ntop returned %d\n",
1199			__func__, error);
1200		goto out;
1201	}
1202
1203	nfs_server_remove_lists(server);
1204	error = nfs4_set_client(server, hostname, sap, salen, buf,
1205				clp->cl_rpcclient->cl_auth->au_flavor,
1206				clp->cl_proto, clnt->cl_timeout,
1207				clp->cl_minorversion, net);
1208	nfs_put_client(clp);
1209	if (error != 0) {
1210		nfs_server_insert_lists(server);
1211		dprintk("<-- %s(): nfs4_set_client returned %d\n",
1212			__func__, error);
1213		goto out;
1214	}
1215
1216	if (server->nfs_client->cl_hostname == NULL)
1217		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1218	nfs_server_insert_lists(server);
1219
1220	error = nfs_probe_destination(server);
1221	if (error < 0)
1222		goto out;
1223
1224	dprintk("<-- %s() succeeded\n", __func__);
1225
1226out:
1227	return error;
1228}