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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/* client.c: NFS client sharing and management code
   3 *
   4 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
   5 * Written by David Howells (dhowells@redhat.com)
   6 */
   7
   8
   9#include <linux/module.h>
  10#include <linux/init.h>
  11#include <linux/sched.h>
  12#include <linux/time.h>
  13#include <linux/kernel.h>
  14#include <linux/mm.h>
  15#include <linux/string.h>
  16#include <linux/stat.h>
  17#include <linux/errno.h>
  18#include <linux/unistd.h>
  19#include <linux/sunrpc/addr.h>
  20#include <linux/sunrpc/clnt.h>
  21#include <linux/sunrpc/stats.h>
  22#include <linux/sunrpc/metrics.h>
  23#include <linux/sunrpc/xprtsock.h>
  24#include <linux/sunrpc/xprtrdma.h>
  25#include <linux/nfs_fs.h>
  26#include <linux/nfs_mount.h>
  27#include <linux/nfs4_mount.h>
  28#include <linux/lockd/bind.h>
  29#include <linux/seq_file.h>
  30#include <linux/mount.h>
  31#include <linux/vfs.h>
  32#include <linux/inet.h>
  33#include <linux/in6.h>
  34#include <linux/slab.h>
  35#include <linux/idr.h>
  36#include <net/ipv6.h>
  37#include <linux/nfs_xdr.h>
  38#include <linux/sunrpc/bc_xprt.h>
  39#include <linux/nsproxy.h>
  40#include <linux/pid_namespace.h>
  41
  42
  43#include "nfs4_fs.h"
  44#include "callback.h"
  45#include "delegation.h"
  46#include "iostat.h"
  47#include "internal.h"
  48#include "fscache.h"
  49#include "pnfs.h"
  50#include "nfs.h"
  51#include "netns.h"
  52#include "sysfs.h"
  53#include "nfs42.h"
  54
  55#define NFSDBG_FACILITY		NFSDBG_CLIENT
  56
  57static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
  58static DEFINE_SPINLOCK(nfs_version_lock);
  59static DEFINE_MUTEX(nfs_version_mutex);
  60static LIST_HEAD(nfs_versions);
  61
  62/*
  63 * RPC cruft for NFS
  64 */
  65static const struct rpc_version *nfs_version[5] = {
  66	[2] = NULL,
  67	[3] = NULL,
  68	[4] = NULL,
  69};
  70
  71const struct rpc_program nfs_program = {
  72	.name			= "nfs",
  73	.number			= NFS_PROGRAM,
  74	.nrvers			= ARRAY_SIZE(nfs_version),
  75	.version		= nfs_version,
  76	.stats			= &nfs_rpcstat,
  77	.pipe_dir_name		= NFS_PIPE_DIRNAME,
  78};
  79
  80struct rpc_stat nfs_rpcstat = {
  81	.program		= &nfs_program
  82};
  83
  84static struct nfs_subversion *find_nfs_version(unsigned int version)
  85{
  86	struct nfs_subversion *nfs;
  87	spin_lock(&nfs_version_lock);
  88
  89	list_for_each_entry(nfs, &nfs_versions, list) {
  90		if (nfs->rpc_ops->version == version) {
  91			spin_unlock(&nfs_version_lock);
  92			return nfs;
  93		}
  94	}
  95
  96	spin_unlock(&nfs_version_lock);
  97	return ERR_PTR(-EPROTONOSUPPORT);
  98}
  99
 100struct nfs_subversion *get_nfs_version(unsigned int version)
 101{
 102	struct nfs_subversion *nfs = find_nfs_version(version);
 103
 104	if (IS_ERR(nfs)) {
 105		mutex_lock(&nfs_version_mutex);
 106		request_module("nfsv%d", version);
 107		nfs = find_nfs_version(version);
 108		mutex_unlock(&nfs_version_mutex);
 109	}
 110
 111	if (!IS_ERR(nfs) && !try_module_get(nfs->owner))
 112		return ERR_PTR(-EAGAIN);
 113	return nfs;
 114}
 115
 116void put_nfs_version(struct nfs_subversion *nfs)
 117{
 118	module_put(nfs->owner);
 119}
 120
 121void register_nfs_version(struct nfs_subversion *nfs)
 122{
 123	spin_lock(&nfs_version_lock);
 124
 125	list_add(&nfs->list, &nfs_versions);
 126	nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
 127
 128	spin_unlock(&nfs_version_lock);
 129}
 130EXPORT_SYMBOL_GPL(register_nfs_version);
 131
 132void unregister_nfs_version(struct nfs_subversion *nfs)
 133{
 134	spin_lock(&nfs_version_lock);
 135
 136	nfs_version[nfs->rpc_ops->version] = NULL;
 137	list_del(&nfs->list);
 138
 139	spin_unlock(&nfs_version_lock);
 140}
 141EXPORT_SYMBOL_GPL(unregister_nfs_version);
 142
 143/*
 144 * Allocate a shared client record
 145 *
 146 * Since these are allocated/deallocated very rarely, we don't
 147 * bother putting them in a slab cache...
 148 */
 149struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 150{
 151	struct nfs_client *clp;
 152	int err = -ENOMEM;
 153
 154	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
 155		goto error_0;
 156
 157	clp->cl_minorversion = cl_init->minorversion;
 158	clp->cl_nfs_mod = cl_init->nfs_mod;
 159	if (!try_module_get(clp->cl_nfs_mod->owner))
 160		goto error_dealloc;
 161
 162	clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
 163
 164	refcount_set(&clp->cl_count, 1);
 165	clp->cl_cons_state = NFS_CS_INITING;
 166
 167	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
 168	clp->cl_addrlen = cl_init->addrlen;
 169
 170	if (cl_init->hostname) {
 171		err = -ENOMEM;
 172		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
 173		if (!clp->cl_hostname)
 174			goto error_cleanup;
 175	}
 176
 177	INIT_LIST_HEAD(&clp->cl_superblocks);
 178	clp->cl_rpcclient = ERR_PTR(-EINVAL);
 179
 180	clp->cl_proto = cl_init->proto;
 181	clp->cl_nconnect = cl_init->nconnect;
 182	clp->cl_net = get_net(cl_init->net);
 183
 184	clp->cl_principal = "*";
 185	nfs_fscache_get_client_cookie(clp);
 186
 187	return clp;
 188
 189error_cleanup:
 190	put_nfs_version(clp->cl_nfs_mod);
 191error_dealloc:
 192	kfree(clp);
 193error_0:
 194	return ERR_PTR(err);
 195}
 196EXPORT_SYMBOL_GPL(nfs_alloc_client);
 197
 198#if IS_ENABLED(CONFIG_NFS_V4)
 199static void nfs_cleanup_cb_ident_idr(struct net *net)
 200{
 201	struct nfs_net *nn = net_generic(net, nfs_net_id);
 202
 203	idr_destroy(&nn->cb_ident_idr);
 204}
 205
 206/* nfs_client_lock held */
 207static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 208{
 209	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 210
 211	if (clp->cl_cb_ident)
 212		idr_remove(&nn->cb_ident_idr, clp->cl_cb_ident);
 213}
 214
 215static void pnfs_init_server(struct nfs_server *server)
 216{
 217	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
 218}
 219
 220#else
 221static void nfs_cleanup_cb_ident_idr(struct net *net)
 222{
 223}
 224
 225static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 226{
 227}
 228
 229static void pnfs_init_server(struct nfs_server *server)
 230{
 231}
 232
 233#endif /* CONFIG_NFS_V4 */
 234
 235/*
 236 * Destroy a shared client record
 237 */
 238void nfs_free_client(struct nfs_client *clp)
 239{
 240	nfs_fscache_release_client_cookie(clp);
 241
 242	/* -EIO all pending I/O */
 243	if (!IS_ERR(clp->cl_rpcclient))
 244		rpc_shutdown_client(clp->cl_rpcclient);
 245
 246	put_net(clp->cl_net);
 247	put_nfs_version(clp->cl_nfs_mod);
 248	kfree(clp->cl_hostname);
 249	kfree(clp->cl_acceptor);
 250	kfree(clp);
 251}
 252EXPORT_SYMBOL_GPL(nfs_free_client);
 253
 254/*
 255 * Release a reference to a shared client record
 256 */
 257void nfs_put_client(struct nfs_client *clp)
 258{
 259	struct nfs_net *nn;
 260
 261	if (!clp)
 262		return;
 263
 264	nn = net_generic(clp->cl_net, nfs_net_id);
 265
 266	if (refcount_dec_and_lock(&clp->cl_count, &nn->nfs_client_lock)) {
 267		list_del(&clp->cl_share_link);
 268		nfs_cb_idr_remove_locked(clp);
 269		spin_unlock(&nn->nfs_client_lock);
 270
 271		WARN_ON_ONCE(!list_empty(&clp->cl_superblocks));
 272
 273		clp->rpc_ops->free_client(clp);
 274	}
 275}
 276EXPORT_SYMBOL_GPL(nfs_put_client);
 277
 278/*
 279 * Find an nfs_client on the list that matches the initialisation data
 280 * that is supplied.
 281 */
 282static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
 283{
 284	struct nfs_client *clp;
 285	const struct sockaddr *sap = data->addr;
 286	struct nfs_net *nn = net_generic(data->net, nfs_net_id);
 287	int error;
 288
 289again:
 290	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 291	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 292		/* Don't match clients that failed to initialise properly */
 293		if (clp->cl_cons_state < 0)
 294			continue;
 295
 296		/* If a client is still initializing then we need to wait */
 297		if (clp->cl_cons_state > NFS_CS_READY) {
 298			refcount_inc(&clp->cl_count);
 299			spin_unlock(&nn->nfs_client_lock);
 300			error = nfs_wait_client_init_complete(clp);
 301			nfs_put_client(clp);
 302			spin_lock(&nn->nfs_client_lock);
 303			if (error < 0)
 304				return ERR_PTR(error);
 305			goto again;
 306		}
 307
 308		/* Different NFS versions cannot share the same nfs_client */
 309		if (clp->rpc_ops != data->nfs_mod->rpc_ops)
 310			continue;
 311
 312		if (clp->cl_proto != data->proto)
 313			continue;
 314		/* Match nfsv4 minorversion */
 315		if (clp->cl_minorversion != data->minorversion)
 316			continue;
 317
 318		/* Match request for a dedicated DS */
 319		if (test_bit(NFS_CS_DS, &data->init_flags) !=
 320		    test_bit(NFS_CS_DS, &clp->cl_flags))
 321			continue;
 322
 323		/* Match the full socket address */
 324		if (!rpc_cmp_addr_port(sap, clap))
 325			/* Match all xprt_switch full socket addresses */
 326			if (IS_ERR(clp->cl_rpcclient) ||
 327                            !rpc_clnt_xprt_switch_has_addr(clp->cl_rpcclient,
 328							   sap))
 329				continue;
 330
 331		refcount_inc(&clp->cl_count);
 332		return clp;
 333	}
 334	return NULL;
 335}
 336
 337/*
 338 * Return true if @clp is done initializing, false if still working on it.
 339 *
 340 * Use nfs_client_init_status to check if it was successful.
 341 */
 342bool nfs_client_init_is_complete(const struct nfs_client *clp)
 343{
 344	return clp->cl_cons_state <= NFS_CS_READY;
 345}
 346EXPORT_SYMBOL_GPL(nfs_client_init_is_complete);
 347
 348/*
 349 * Return 0 if @clp was successfully initialized, -errno otherwise.
 350 *
 351 * This must be called *after* nfs_client_init_is_complete() returns true,
 352 * otherwise it will pop WARN_ON_ONCE and return -EINVAL
 353 */
 354int nfs_client_init_status(const struct nfs_client *clp)
 355{
 356	/* called without checking nfs_client_init_is_complete */
 357	if (clp->cl_cons_state > NFS_CS_READY) {
 358		WARN_ON_ONCE(1);
 359		return -EINVAL;
 360	}
 361	return clp->cl_cons_state;
 362}
 363EXPORT_SYMBOL_GPL(nfs_client_init_status);
 364
 365int nfs_wait_client_init_complete(const struct nfs_client *clp)
 366{
 367	return wait_event_killable(nfs_client_active_wq,
 368			nfs_client_init_is_complete(clp));
 369}
 370EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
 371
 372/*
 373 * Found an existing client.  Make sure it's ready before returning.
 374 */
 375static struct nfs_client *
 376nfs_found_client(const struct nfs_client_initdata *cl_init,
 377		 struct nfs_client *clp)
 378{
 379	int error;
 380
 381	error = nfs_wait_client_init_complete(clp);
 382	if (error < 0) {
 383		nfs_put_client(clp);
 384		return ERR_PTR(-ERESTARTSYS);
 385	}
 386
 387	if (clp->cl_cons_state < NFS_CS_READY) {
 388		error = clp->cl_cons_state;
 389		nfs_put_client(clp);
 390		return ERR_PTR(error);
 391	}
 392
 393	smp_rmb();
 394	return clp;
 395}
 396
 397/*
 398 * Look up a client by IP address and protocol version
 399 * - creates a new record if one doesn't yet exist
 400 */
 401struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
 402{
 403	struct nfs_client *clp, *new = NULL;
 404	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
 405	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
 406
 407	if (cl_init->hostname == NULL) {
 408		WARN_ON(1);
 409		return NULL;
 410	}
 411
 412	/* see if the client already exists */
 413	do {
 414		spin_lock(&nn->nfs_client_lock);
 415
 416		clp = nfs_match_client(cl_init);
 417		if (clp) {
 418			spin_unlock(&nn->nfs_client_lock);
 419			if (new)
 420				new->rpc_ops->free_client(new);
 421			if (IS_ERR(clp))
 422				return clp;
 423			return nfs_found_client(cl_init, clp);
 424		}
 425		if (new) {
 426			list_add_tail(&new->cl_share_link,
 427					&nn->nfs_client_list);
 428			spin_unlock(&nn->nfs_client_lock);
 429			new->cl_flags = cl_init->init_flags;
 430			return rpc_ops->init_client(new, cl_init);
 431		}
 432
 433		spin_unlock(&nn->nfs_client_lock);
 434
 435		new = rpc_ops->alloc_client(cl_init);
 436	} while (!IS_ERR(new));
 437
 438	return new;
 439}
 440EXPORT_SYMBOL_GPL(nfs_get_client);
 441
 442/*
 443 * Mark a server as ready or failed
 444 */
 445void nfs_mark_client_ready(struct nfs_client *clp, int state)
 446{
 447	smp_wmb();
 448	clp->cl_cons_state = state;
 449	wake_up_all(&nfs_client_active_wq);
 450}
 451EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
 452
 453/*
 454 * Initialise the timeout values for a connection
 455 */
 456void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 457				    int timeo, int retrans)
 458{
 459	to->to_initval = timeo * HZ / 10;
 460	to->to_retries = retrans;
 461
 462	switch (proto) {
 463	case XPRT_TRANSPORT_TCP:
 464	case XPRT_TRANSPORT_RDMA:
 465		if (retrans == NFS_UNSPEC_RETRANS)
 466			to->to_retries = NFS_DEF_TCP_RETRANS;
 467		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
 468			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
 469		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
 470			to->to_initval = NFS_MAX_TCP_TIMEOUT;
 471		to->to_increment = to->to_initval;
 472		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
 473		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
 474			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
 475		if (to->to_maxval < to->to_initval)
 476			to->to_maxval = to->to_initval;
 477		to->to_exponential = 0;
 478		break;
 479#ifndef CONFIG_NFS_DISABLE_UDP_SUPPORT
 480	case XPRT_TRANSPORT_UDP:
 481		if (retrans == NFS_UNSPEC_RETRANS)
 482			to->to_retries = NFS_DEF_UDP_RETRANS;
 483		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
 484			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
 485		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
 486			to->to_initval = NFS_MAX_UDP_TIMEOUT;
 487		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
 488		to->to_exponential = 1;
 489		break;
 490#endif
 491	default:
 492		BUG();
 493	}
 494}
 495EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
 496
 497/*
 498 * Create an RPC client handle
 499 */
 500int nfs_create_rpc_client(struct nfs_client *clp,
 501			  const struct nfs_client_initdata *cl_init,
 502			  rpc_authflavor_t flavor)
 503{
 504	struct rpc_clnt		*clnt = NULL;
 505	struct rpc_create_args args = {
 506		.net		= clp->cl_net,
 507		.protocol	= clp->cl_proto,
 508		.nconnect	= clp->cl_nconnect,
 509		.address	= (struct sockaddr *)&clp->cl_addr,
 510		.addrsize	= clp->cl_addrlen,
 511		.timeout	= cl_init->timeparms,
 512		.servername	= clp->cl_hostname,
 513		.nodename	= cl_init->nodename,
 514		.program	= &nfs_program,
 515		.version	= clp->rpc_ops->version,
 516		.authflavor	= flavor,
 517		.cred		= cl_init->cred,
 518	};
 519
 520	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
 521		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
 522	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
 523		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
 524	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
 525		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
 526	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
 527		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
 528	if (test_bit(NFS_CS_NOPING, &clp->cl_flags))
 529		args.flags |= RPC_CLNT_CREATE_NOPING;
 530	if (test_bit(NFS_CS_REUSEPORT, &clp->cl_flags))
 531		args.flags |= RPC_CLNT_CREATE_REUSEPORT;
 532
 533	if (!IS_ERR(clp->cl_rpcclient))
 534		return 0;
 535
 536	clnt = rpc_create(&args);
 537	if (IS_ERR(clnt)) {
 538		dprintk("%s: cannot create RPC client. Error = %ld\n",
 539				__func__, PTR_ERR(clnt));
 540		return PTR_ERR(clnt);
 541	}
 542
 543	clnt->cl_principal = clp->cl_principal;
 544	clp->cl_rpcclient = clnt;
 545	return 0;
 546}
 547EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
 548
 549/*
 550 * Version 2 or 3 client destruction
 551 */
 552static void nfs_destroy_server(struct nfs_server *server)
 553{
 554	if (server->nlm_host)
 555		nlmclnt_done(server->nlm_host);
 556}
 557
 558/*
 559 * Version 2 or 3 lockd setup
 560 */
 561static int nfs_start_lockd(struct nfs_server *server)
 562{
 563	struct nlm_host *host;
 564	struct nfs_client *clp = server->nfs_client;
 565	struct nlmclnt_initdata nlm_init = {
 566		.hostname	= clp->cl_hostname,
 567		.address	= (struct sockaddr *)&clp->cl_addr,
 568		.addrlen	= clp->cl_addrlen,
 569		.nfs_version	= clp->rpc_ops->version,
 570		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
 571					1 : 0,
 572		.net		= clp->cl_net,
 573		.nlmclnt_ops 	= clp->cl_nfs_mod->rpc_ops->nlmclnt_ops,
 574		.cred		= current_cred(),
 575	};
 576
 577	if (nlm_init.nfs_version > 3)
 578		return 0;
 579	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
 580			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
 581		return 0;
 582
 583	switch (clp->cl_proto) {
 584		default:
 585			nlm_init.protocol = IPPROTO_TCP;
 586			break;
 587#ifndef CONFIG_NFS_DISABLE_UDP_SUPPORT
 588		case XPRT_TRANSPORT_UDP:
 589			nlm_init.protocol = IPPROTO_UDP;
 590#endif
 591	}
 592
 593	host = nlmclnt_init(&nlm_init);
 594	if (IS_ERR(host))
 595		return PTR_ERR(host);
 596
 597	server->nlm_host = host;
 598	server->destroy = nfs_destroy_server;
 599	return 0;
 600}
 601
 602/*
 603 * Create a general RPC client
 604 */
 605int nfs_init_server_rpcclient(struct nfs_server *server,
 606		const struct rpc_timeout *timeo,
 607		rpc_authflavor_t pseudoflavour)
 608{
 609	struct nfs_client *clp = server->nfs_client;
 610
 611	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
 612							pseudoflavour);
 613	if (IS_ERR(server->client)) {
 614		dprintk("%s: couldn't create rpc_client!\n", __func__);
 615		return PTR_ERR(server->client);
 616	}
 617
 618	memcpy(&server->client->cl_timeout_default,
 619			timeo,
 620			sizeof(server->client->cl_timeout_default));
 621	server->client->cl_timeout = &server->client->cl_timeout_default;
 622	server->client->cl_softrtry = 0;
 623	if (server->flags & NFS_MOUNT_SOFTERR)
 624		server->client->cl_softerr = 1;
 625	if (server->flags & NFS_MOUNT_SOFT)
 626		server->client->cl_softrtry = 1;
 627
 628	return 0;
 629}
 630EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
 631
 632/**
 633 * nfs_init_client - Initialise an NFS2 or NFS3 client
 634 *
 635 * @clp: nfs_client to initialise
 636 * @cl_init: Initialisation parameters
 637 *
 638 * Returns pointer to an NFS client, or an ERR_PTR value.
 639 */
 640struct nfs_client *nfs_init_client(struct nfs_client *clp,
 641				   const struct nfs_client_initdata *cl_init)
 642{
 643	int error;
 644
 645	/* the client is already initialised */
 646	if (clp->cl_cons_state == NFS_CS_READY)
 647		return clp;
 648
 649	/*
 650	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
 651	 * - RFC 2623, sec 2.3.2
 652	 */
 653	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
 654	nfs_mark_client_ready(clp, error == 0 ? NFS_CS_READY : error);
 655	if (error < 0) {
 656		nfs_put_client(clp);
 657		clp = ERR_PTR(error);
 658	}
 659	return clp;
 660}
 661EXPORT_SYMBOL_GPL(nfs_init_client);
 662
 663/*
 664 * Create a version 2 or 3 client
 665 */
 666static int nfs_init_server(struct nfs_server *server,
 667			   const struct fs_context *fc)
 668{
 669	const struct nfs_fs_context *ctx = nfs_fc2context(fc);
 670	struct rpc_timeout timeparms;
 671	struct nfs_client_initdata cl_init = {
 672		.hostname = ctx->nfs_server.hostname,
 673		.addr = (const struct sockaddr *)&ctx->nfs_server.address,
 674		.addrlen = ctx->nfs_server.addrlen,
 675		.nfs_mod = ctx->nfs_mod,
 676		.proto = ctx->nfs_server.protocol,
 677		.net = fc->net_ns,
 678		.timeparms = &timeparms,
 679		.cred = server->cred,
 680		.nconnect = ctx->nfs_server.nconnect,
 681		.init_flags = (1UL << NFS_CS_REUSEPORT),
 682	};
 683	struct nfs_client *clp;
 684	int error;
 685
 686	nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
 687				ctx->timeo, ctx->retrans);
 688	if (ctx->flags & NFS_MOUNT_NORESVPORT)
 689		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 690
 691	/* Allocate or find a client reference we can use */
 692	clp = nfs_get_client(&cl_init);
 693	if (IS_ERR(clp))
 694		return PTR_ERR(clp);
 695
 696	server->nfs_client = clp;
 697
 698	/* Initialise the client representation from the mount data */
 699	server->flags = ctx->flags;
 700	server->options = ctx->options;
 701	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
 702		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
 703		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
 704
 705	if (ctx->rsize)
 706		server->rsize = nfs_block_size(ctx->rsize, NULL);
 707	if (ctx->wsize)
 708		server->wsize = nfs_block_size(ctx->wsize, NULL);
 709
 710	server->acregmin = ctx->acregmin * HZ;
 711	server->acregmax = ctx->acregmax * HZ;
 712	server->acdirmin = ctx->acdirmin * HZ;
 713	server->acdirmax = ctx->acdirmax * HZ;
 714
 715	/* Start lockd here, before we might error out */
 716	error = nfs_start_lockd(server);
 717	if (error < 0)
 718		goto error;
 719
 720	server->port = ctx->nfs_server.port;
 721	server->auth_info = ctx->auth_info;
 722
 723	error = nfs_init_server_rpcclient(server, &timeparms,
 724					  ctx->selected_flavor);
 725	if (error < 0)
 726		goto error;
 727
 728	/* Preserve the values of mount_server-related mount options */
 729	if (ctx->mount_server.addrlen) {
 730		memcpy(&server->mountd_address, &ctx->mount_server.address,
 731			ctx->mount_server.addrlen);
 732		server->mountd_addrlen = ctx->mount_server.addrlen;
 733	}
 734	server->mountd_version = ctx->mount_server.version;
 735	server->mountd_port = ctx->mount_server.port;
 736	server->mountd_protocol = ctx->mount_server.protocol;
 737
 738	server->namelen  = ctx->namlen;
 739	return 0;
 740
 741error:
 742	server->nfs_client = NULL;
 743	nfs_put_client(clp);
 744	return error;
 745}
 746
 747/*
 748 * Load up the server record from information gained in an fsinfo record
 749 */
 750static void nfs_server_set_fsinfo(struct nfs_server *server,
 751				  struct nfs_fsinfo *fsinfo)
 752{
 753	unsigned long max_rpc_payload, raw_max_rpc_payload;
 754
 755	/* Work out a lot of parameters */
 756	if (server->rsize == 0)
 757		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
 758	if (server->wsize == 0)
 759		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
 760
 761	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
 762		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
 763	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
 764		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
 765
 766	raw_max_rpc_payload = rpc_max_payload(server->client);
 767	max_rpc_payload = nfs_block_size(raw_max_rpc_payload, NULL);
 768
 769	if (server->rsize > max_rpc_payload)
 770		server->rsize = max_rpc_payload;
 771	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
 772		server->rsize = NFS_MAX_FILE_IO_SIZE;
 773	server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
 774
 775	if (server->wsize > max_rpc_payload)
 776		server->wsize = max_rpc_payload;
 777	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
 778		server->wsize = NFS_MAX_FILE_IO_SIZE;
 779	server->wpages = (server->wsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
 780
 781	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
 782
 783	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
 784	if (server->dtsize > PAGE_SIZE * NFS_MAX_READDIR_PAGES)
 785		server->dtsize = PAGE_SIZE * NFS_MAX_READDIR_PAGES;
 786	if (server->dtsize > server->rsize)
 787		server->dtsize = server->rsize;
 788
 789	if (server->flags & NFS_MOUNT_NOAC) {
 790		server->acregmin = server->acregmax = 0;
 791		server->acdirmin = server->acdirmax = 0;
 792	}
 793
 794	server->maxfilesize = fsinfo->maxfilesize;
 795
 796	server->time_delta = fsinfo->time_delta;
 797
 798	server->clone_blksize = fsinfo->clone_blksize;
 799	/* We're airborne Set socket buffersize */
 800	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
 801
 802#ifdef CONFIG_NFS_V4_2
 803	/*
 804	 * Defaults until limited by the session parameters.
 805	 */
 806	server->gxasize = min_t(unsigned int, raw_max_rpc_payload,
 807				XATTR_SIZE_MAX);
 808	server->sxasize = min_t(unsigned int, raw_max_rpc_payload,
 809				XATTR_SIZE_MAX);
 810	server->lxasize = min_t(unsigned int, raw_max_rpc_payload,
 811				nfs42_listxattr_xdrsize(XATTR_LIST_MAX));
 812
 813	if (fsinfo->xattr_support)
 814		server->caps |= NFS_CAP_XATTR;
 815#endif
 816}
 817
 818/*
 819 * Probe filesystem information, including the FSID on v2/v3
 820 */
 821int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
 822{
 823	struct nfs_fsinfo fsinfo;
 824	struct nfs_client *clp = server->nfs_client;
 825	int error;
 826
 827	if (clp->rpc_ops->set_capabilities != NULL) {
 828		error = clp->rpc_ops->set_capabilities(server, mntfh);
 829		if (error < 0)
 830			return error;
 831	}
 832
 833	fsinfo.fattr = fattr;
 834	fsinfo.nlayouttypes = 0;
 835	memset(fsinfo.layouttype, 0, sizeof(fsinfo.layouttype));
 836	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
 837	if (error < 0)
 838		return error;
 839
 840	nfs_server_set_fsinfo(server, &fsinfo);
 841
 842	/* Get some general file system info */
 843	if (server->namelen == 0) {
 844		struct nfs_pathconf pathinfo;
 845
 846		pathinfo.fattr = fattr;
 847		nfs_fattr_init(fattr);
 848
 849		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
 850			server->namelen = pathinfo.max_namelen;
 851	}
 852
 853	return 0;
 854}
 855EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
 856
 857/*
 858 * Copy useful information when duplicating a server record
 859 */
 860void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
 861{
 862	target->flags = source->flags;
 863	target->rsize = source->rsize;
 864	target->wsize = source->wsize;
 865	target->acregmin = source->acregmin;
 866	target->acregmax = source->acregmax;
 867	target->acdirmin = source->acdirmin;
 868	target->acdirmax = source->acdirmax;
 869	target->caps = source->caps;
 870	target->options = source->options;
 871	target->auth_info = source->auth_info;
 872	target->port = source->port;
 873}
 874EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
 875
 876void nfs_server_insert_lists(struct nfs_server *server)
 877{
 878	struct nfs_client *clp = server->nfs_client;
 879	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 880
 881	spin_lock(&nn->nfs_client_lock);
 882	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
 883	list_add_tail(&server->master_link, &nn->nfs_volume_list);
 884	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
 885	spin_unlock(&nn->nfs_client_lock);
 886
 887}
 888EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
 889
 890void nfs_server_remove_lists(struct nfs_server *server)
 891{
 892	struct nfs_client *clp = server->nfs_client;
 893	struct nfs_net *nn;
 894
 895	if (clp == NULL)
 896		return;
 897	nn = net_generic(clp->cl_net, nfs_net_id);
 898	spin_lock(&nn->nfs_client_lock);
 899	list_del_rcu(&server->client_link);
 900	if (list_empty(&clp->cl_superblocks))
 901		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
 902	list_del(&server->master_link);
 903	spin_unlock(&nn->nfs_client_lock);
 904
 905	synchronize_rcu();
 906}
 907EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
 908
 909/*
 910 * Allocate and initialise a server record
 911 */
 912struct nfs_server *nfs_alloc_server(void)
 913{
 914	struct nfs_server *server;
 915
 916	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
 917	if (!server)
 918		return NULL;
 919
 920	server->client = server->client_acl = ERR_PTR(-EINVAL);
 921
 922	/* Zero out the NFS state stuff */
 923	INIT_LIST_HEAD(&server->client_link);
 924	INIT_LIST_HEAD(&server->master_link);
 925	INIT_LIST_HEAD(&server->delegations);
 926	INIT_LIST_HEAD(&server->layouts);
 927	INIT_LIST_HEAD(&server->state_owners_lru);
 928	INIT_LIST_HEAD(&server->ss_copies);
 929
 930	atomic_set(&server->active, 0);
 931
 932	server->io_stats = nfs_alloc_iostats();
 933	if (!server->io_stats) {
 934		kfree(server);
 935		return NULL;
 936	}
 937
 938	ida_init(&server->openowner_id);
 939	ida_init(&server->lockowner_id);
 940	pnfs_init_server(server);
 941	rpc_init_wait_queue(&server->uoc_rpcwaitq, "NFS UOC");
 942
 943	return server;
 944}
 945EXPORT_SYMBOL_GPL(nfs_alloc_server);
 946
 947/*
 948 * Free up a server record
 949 */
 950void nfs_free_server(struct nfs_server *server)
 951{
 952	nfs_server_remove_lists(server);
 953
 954	if (server->destroy != NULL)
 955		server->destroy(server);
 956
 957	if (!IS_ERR(server->client_acl))
 958		rpc_shutdown_client(server->client_acl);
 959	if (!IS_ERR(server->client))
 960		rpc_shutdown_client(server->client);
 961
 962	nfs_put_client(server->nfs_client);
 963
 964	ida_destroy(&server->lockowner_id);
 965	ida_destroy(&server->openowner_id);
 966	nfs_free_iostats(server->io_stats);
 967	put_cred(server->cred);
 968	kfree(server);
 969	nfs_release_automount_timer();
 970}
 971EXPORT_SYMBOL_GPL(nfs_free_server);
 972
 973/*
 974 * Create a version 2 or 3 volume record
 975 * - keyed on server and FSID
 976 */
 977struct nfs_server *nfs_create_server(struct fs_context *fc)
 978{
 979	struct nfs_fs_context *ctx = nfs_fc2context(fc);
 980	struct nfs_server *server;
 981	struct nfs_fattr *fattr;
 982	int error;
 983
 984	server = nfs_alloc_server();
 985	if (!server)
 986		return ERR_PTR(-ENOMEM);
 987
 988	server->cred = get_cred(current_cred());
 989
 990	error = -ENOMEM;
 991	fattr = nfs_alloc_fattr();
 992	if (fattr == NULL)
 993		goto error;
 994
 995	/* Get a client representation */
 996	error = nfs_init_server(server, fc);
 997	if (error < 0)
 998		goto error;
 999
1000	/* Probe the root fh to retrieve its FSID */
1001	error = nfs_probe_fsinfo(server, ctx->mntfh, fattr);
1002	if (error < 0)
1003		goto error;
1004	if (server->nfs_client->rpc_ops->version == 3) {
1005		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
1006			server->namelen = NFS3_MAXNAMLEN;
1007		if (!(ctx->flags & NFS_MOUNT_NORDIRPLUS))
1008			server->caps |= NFS_CAP_READDIRPLUS;
1009	} else {
1010		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
1011			server->namelen = NFS2_MAXNAMLEN;
1012	}
1013
1014	if (!(fattr->valid & NFS_ATTR_FATTR)) {
1015		error = ctx->nfs_mod->rpc_ops->getattr(server, ctx->mntfh,
1016						       fattr, NULL, NULL);
1017		if (error < 0) {
1018			dprintk("nfs_create_server: getattr error = %d\n", -error);
1019			goto error;
1020		}
1021	}
1022	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1023
1024	dprintk("Server FSID: %llx:%llx\n",
1025		(unsigned long long) server->fsid.major,
1026		(unsigned long long) server->fsid.minor);
1027
1028	nfs_server_insert_lists(server);
1029	server->mount_time = jiffies;
1030	nfs_free_fattr(fattr);
1031	return server;
1032
1033error:
1034	nfs_free_fattr(fattr);
1035	nfs_free_server(server);
1036	return ERR_PTR(error);
1037}
1038EXPORT_SYMBOL_GPL(nfs_create_server);
1039
1040/*
1041 * Clone an NFS2, NFS3 or NFS4 server record
1042 */
1043struct nfs_server *nfs_clone_server(struct nfs_server *source,
1044				    struct nfs_fh *fh,
1045				    struct nfs_fattr *fattr,
1046				    rpc_authflavor_t flavor)
1047{
1048	struct nfs_server *server;
1049	struct nfs_fattr *fattr_fsinfo;
1050	int error;
1051
1052	server = nfs_alloc_server();
1053	if (!server)
1054		return ERR_PTR(-ENOMEM);
1055
1056	server->cred = get_cred(source->cred);
1057
1058	error = -ENOMEM;
1059	fattr_fsinfo = nfs_alloc_fattr();
1060	if (fattr_fsinfo == NULL)
1061		goto out_free_server;
1062
1063	/* Copy data from the source */
1064	server->nfs_client = source->nfs_client;
1065	server->destroy = source->destroy;
1066	refcount_inc(&server->nfs_client->cl_count);
1067	nfs_server_copy_userdata(server, source);
1068
1069	server->fsid = fattr->fsid;
1070
1071	error = nfs_init_server_rpcclient(server,
1072			source->client->cl_timeout,
1073			flavor);
1074	if (error < 0)
1075		goto out_free_server;
1076
1077	/* probe the filesystem info for this server filesystem */
1078	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1079	if (error < 0)
1080		goto out_free_server;
1081
1082	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1083		server->namelen = NFS4_MAXNAMLEN;
1084
1085	error = nfs_start_lockd(server);
1086	if (error < 0)
1087		goto out_free_server;
1088
1089	nfs_server_insert_lists(server);
1090	server->mount_time = jiffies;
1091
1092	nfs_free_fattr(fattr_fsinfo);
1093	return server;
1094
1095out_free_server:
1096	nfs_free_fattr(fattr_fsinfo);
1097	nfs_free_server(server);
1098	return ERR_PTR(error);
1099}
1100EXPORT_SYMBOL_GPL(nfs_clone_server);
1101
1102void nfs_clients_init(struct net *net)
1103{
1104	struct nfs_net *nn = net_generic(net, nfs_net_id);
1105
1106	INIT_LIST_HEAD(&nn->nfs_client_list);
1107	INIT_LIST_HEAD(&nn->nfs_volume_list);
1108#if IS_ENABLED(CONFIG_NFS_V4)
1109	idr_init(&nn->cb_ident_idr);
1110#endif
1111	spin_lock_init(&nn->nfs_client_lock);
1112	nn->boot_time = ktime_get_real();
1113
1114	nfs_netns_sysfs_setup(nn, net);
1115}
1116
1117void nfs_clients_exit(struct net *net)
1118{
1119	struct nfs_net *nn = net_generic(net, nfs_net_id);
1120
1121	nfs_netns_sysfs_destroy(nn);
1122	nfs_cleanup_cb_ident_idr(net);
1123	WARN_ON_ONCE(!list_empty(&nn->nfs_client_list));
1124	WARN_ON_ONCE(!list_empty(&nn->nfs_volume_list));
1125}
1126
1127#ifdef CONFIG_PROC_FS
1128static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1129static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1130static void nfs_server_list_stop(struct seq_file *p, void *v);
1131static int nfs_server_list_show(struct seq_file *m, void *v);
1132
1133static const struct seq_operations nfs_server_list_ops = {
1134	.start	= nfs_server_list_start,
1135	.next	= nfs_server_list_next,
1136	.stop	= nfs_server_list_stop,
1137	.show	= nfs_server_list_show,
1138};
1139
1140static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1141static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1142static void nfs_volume_list_stop(struct seq_file *p, void *v);
1143static int nfs_volume_list_show(struct seq_file *m, void *v);
1144
1145static const struct seq_operations nfs_volume_list_ops = {
1146	.start	= nfs_volume_list_start,
1147	.next	= nfs_volume_list_next,
1148	.stop	= nfs_volume_list_stop,
1149	.show	= nfs_volume_list_show,
1150};
1151
1152/*
1153 * set up the iterator to start reading from the server list and return the first item
1154 */
1155static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1156				__acquires(&nn->nfs_client_lock)
1157{
1158	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1159
1160	/* lock the list against modification */
1161	spin_lock(&nn->nfs_client_lock);
1162	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1163}
1164
1165/*
1166 * move to next server
1167 */
1168static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1169{
1170	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1171
1172	return seq_list_next(v, &nn->nfs_client_list, pos);
1173}
1174
1175/*
1176 * clean up after reading from the transports list
1177 */
1178static void nfs_server_list_stop(struct seq_file *p, void *v)
1179				__releases(&nn->nfs_client_lock)
1180{
1181	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1182
1183	spin_unlock(&nn->nfs_client_lock);
1184}
1185
1186/*
1187 * display a header line followed by a load of call lines
1188 */
1189static int nfs_server_list_show(struct seq_file *m, void *v)
1190{
1191	struct nfs_client *clp;
1192	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1193
1194	/* display header on line 1 */
1195	if (v == &nn->nfs_client_list) {
1196		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1197		return 0;
1198	}
1199
1200	/* display one transport per line on subsequent lines */
1201	clp = list_entry(v, struct nfs_client, cl_share_link);
1202
1203	/* Check if the client is initialized */
1204	if (clp->cl_cons_state != NFS_CS_READY)
1205		return 0;
1206
1207	rcu_read_lock();
1208	seq_printf(m, "v%u %s %s %3d %s\n",
1209		   clp->rpc_ops->version,
1210		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1211		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1212		   refcount_read(&clp->cl_count),
1213		   clp->cl_hostname);
1214	rcu_read_unlock();
1215
1216	return 0;
1217}
1218
1219/*
1220 * set up the iterator to start reading from the volume list and return the first item
1221 */
1222static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1223				__acquires(&nn->nfs_client_lock)
1224{
1225	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1226
1227	/* lock the list against modification */
1228	spin_lock(&nn->nfs_client_lock);
1229	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1230}
1231
1232/*
1233 * move to next volume
1234 */
1235static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1236{
1237	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1238
1239	return seq_list_next(v, &nn->nfs_volume_list, pos);
1240}
1241
1242/*
1243 * clean up after reading from the transports list
1244 */
1245static void nfs_volume_list_stop(struct seq_file *p, void *v)
1246				__releases(&nn->nfs_client_lock)
1247{
1248	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1249
1250	spin_unlock(&nn->nfs_client_lock);
1251}
1252
1253/*
1254 * display a header line followed by a load of call lines
1255 */
1256static int nfs_volume_list_show(struct seq_file *m, void *v)
1257{
1258	struct nfs_server *server;
1259	struct nfs_client *clp;
1260	char dev[13];	// 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1261	char fsid[34];	// 2 * 16 for %llx, 1 for ':', 1 for '\0'
1262	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1263
1264	/* display header on line 1 */
1265	if (v == &nn->nfs_volume_list) {
1266		seq_puts(m, "NV SERVER   PORT DEV          FSID"
1267			    "                              FSC\n");
1268		return 0;
1269	}
1270	/* display one transport per line on subsequent lines */
1271	server = list_entry(v, struct nfs_server, master_link);
1272	clp = server->nfs_client;
1273
1274	snprintf(dev, sizeof(dev), "%u:%u",
1275		 MAJOR(server->s_dev), MINOR(server->s_dev));
1276
1277	snprintf(fsid, sizeof(fsid), "%llx:%llx",
1278		 (unsigned long long) server->fsid.major,
1279		 (unsigned long long) server->fsid.minor);
1280
1281	rcu_read_lock();
1282	seq_printf(m, "v%u %s %s %-12s %-33s %s\n",
1283		   clp->rpc_ops->version,
1284		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1285		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1286		   dev,
1287		   fsid,
1288		   nfs_server_fscache_state(server));
1289	rcu_read_unlock();
1290
1291	return 0;
1292}
1293
1294int nfs_fs_proc_net_init(struct net *net)
1295{
1296	struct nfs_net *nn = net_generic(net, nfs_net_id);
1297	struct proc_dir_entry *p;
1298
1299	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1300	if (!nn->proc_nfsfs)
1301		goto error_0;
1302
1303	/* a file of servers with which we're dealing */
1304	p = proc_create_net("servers", S_IFREG|S_IRUGO, nn->proc_nfsfs,
1305			&nfs_server_list_ops, sizeof(struct seq_net_private));
1306	if (!p)
1307		goto error_1;
1308
1309	/* a file of volumes that we have mounted */
1310	p = proc_create_net("volumes", S_IFREG|S_IRUGO, nn->proc_nfsfs,
1311			&nfs_volume_list_ops, sizeof(struct seq_net_private));
1312	if (!p)
1313		goto error_1;
1314	return 0;
1315
1316error_1:
1317	remove_proc_subtree("nfsfs", net->proc_net);
1318error_0:
1319	return -ENOMEM;
1320}
1321
1322void nfs_fs_proc_net_exit(struct net *net)
1323{
1324	remove_proc_subtree("nfsfs", net->proc_net);
1325}
1326
1327/*
1328 * initialise the /proc/fs/nfsfs/ directory
1329 */
1330int __init nfs_fs_proc_init(void)
1331{
1332	if (!proc_mkdir("fs/nfsfs", NULL))
1333		goto error_0;
1334
1335	/* a file of servers with which we're dealing */
1336	if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1337		goto error_1;
1338
1339	/* a file of volumes that we have mounted */
1340	if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1341		goto error_1;
1342
1343	return 0;
1344error_1:
1345	remove_proc_subtree("fs/nfsfs", NULL);
1346error_0:
1347	return -ENOMEM;
1348}
1349
1350/*
1351 * clean up the /proc/fs/nfsfs/ directory
1352 */
1353void nfs_fs_proc_exit(void)
1354{
1355	remove_proc_subtree("fs/nfsfs", NULL);
1356}
1357
1358#endif /* CONFIG_PROC_FS */
   1/* client.c: NFS client sharing and management code
   2 *
   3 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
   4 * Written by David Howells (dhowells@redhat.com)
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License
   8 * as published by the Free Software Foundation; either version
   9 * 2 of the License, or (at your option) any later version.
  10 */
  11
  12
  13#include <linux/module.h>
  14#include <linux/init.h>
  15#include <linux/sched.h>
  16#include <linux/time.h>
  17#include <linux/kernel.h>
  18#include <linux/mm.h>
  19#include <linux/string.h>
  20#include <linux/stat.h>
  21#include <linux/errno.h>
  22#include <linux/unistd.h>
  23#include <linux/sunrpc/addr.h>
  24#include <linux/sunrpc/clnt.h>
  25#include <linux/sunrpc/stats.h>
  26#include <linux/sunrpc/metrics.h>
  27#include <linux/sunrpc/xprtsock.h>
  28#include <linux/sunrpc/xprtrdma.h>
  29#include <linux/nfs_fs.h>
  30#include <linux/nfs_mount.h>
  31#include <linux/nfs4_mount.h>
  32#include <linux/lockd/bind.h>
  33#include <linux/seq_file.h>
  34#include <linux/mount.h>
  35#include <linux/vfs.h>
  36#include <linux/inet.h>
  37#include <linux/in6.h>
  38#include <linux/slab.h>
  39#include <linux/idr.h>
  40#include <net/ipv6.h>
  41#include <linux/nfs_xdr.h>
  42#include <linux/sunrpc/bc_xprt.h>
  43#include <linux/nsproxy.h>
  44#include <linux/pid_namespace.h>
  45
  46
  47#include "nfs4_fs.h"
  48#include "callback.h"
  49#include "delegation.h"
  50#include "iostat.h"
  51#include "internal.h"
  52#include "fscache.h"
  53#include "pnfs.h"
  54#include "nfs.h"
  55#include "netns.h"
  56
  57#define NFSDBG_FACILITY		NFSDBG_CLIENT
  58
  59static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
  60static DEFINE_SPINLOCK(nfs_version_lock);
  61static DEFINE_MUTEX(nfs_version_mutex);
  62static LIST_HEAD(nfs_versions);
  63
  64/*
  65 * RPC cruft for NFS
  66 */
  67static const struct rpc_version *nfs_version[5] = {
  68	[2] = NULL,
  69	[3] = NULL,
  70	[4] = NULL,
  71};
  72
  73const struct rpc_program nfs_program = {
  74	.name			= "nfs",
  75	.number			= NFS_PROGRAM,
  76	.nrvers			= ARRAY_SIZE(nfs_version),
  77	.version		= nfs_version,
  78	.stats			= &nfs_rpcstat,
  79	.pipe_dir_name		= NFS_PIPE_DIRNAME,
  80};
  81
  82struct rpc_stat nfs_rpcstat = {
  83	.program		= &nfs_program
  84};
  85
  86static struct nfs_subversion *find_nfs_version(unsigned int version)
  87{
  88	struct nfs_subversion *nfs;
  89	spin_lock(&nfs_version_lock);
  90
  91	list_for_each_entry(nfs, &nfs_versions, list) {
  92		if (nfs->rpc_ops->version == version) {
  93			spin_unlock(&nfs_version_lock);
  94			return nfs;
  95		}
  96	}
  97
  98	spin_unlock(&nfs_version_lock);
  99	return ERR_PTR(-EPROTONOSUPPORT);
 100}
 101
 102struct nfs_subversion *get_nfs_version(unsigned int version)
 103{
 104	struct nfs_subversion *nfs = find_nfs_version(version);
 105
 106	if (IS_ERR(nfs)) {
 107		mutex_lock(&nfs_version_mutex);
 108		request_module("nfsv%d", version);
 109		nfs = find_nfs_version(version);
 110		mutex_unlock(&nfs_version_mutex);
 111	}
 112
 113	if (!IS_ERR(nfs) && !try_module_get(nfs->owner))
 114		return ERR_PTR(-EAGAIN);
 115	return nfs;
 116}
 117
 118void put_nfs_version(struct nfs_subversion *nfs)
 119{
 120	module_put(nfs->owner);
 121}
 122
 123void register_nfs_version(struct nfs_subversion *nfs)
 124{
 125	spin_lock(&nfs_version_lock);
 126
 127	list_add(&nfs->list, &nfs_versions);
 128	nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
 129
 130	spin_unlock(&nfs_version_lock);
 131}
 132EXPORT_SYMBOL_GPL(register_nfs_version);
 133
 134void unregister_nfs_version(struct nfs_subversion *nfs)
 135{
 136	spin_lock(&nfs_version_lock);
 137
 138	nfs_version[nfs->rpc_ops->version] = NULL;
 139	list_del(&nfs->list);
 140
 141	spin_unlock(&nfs_version_lock);
 142}
 143EXPORT_SYMBOL_GPL(unregister_nfs_version);
 144
 145/*
 146 * Allocate a shared client record
 147 *
 148 * Since these are allocated/deallocated very rarely, we don't
 149 * bother putting them in a slab cache...
 150 */
 151struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 152{
 153	struct nfs_client *clp;
 154	struct rpc_cred *cred;
 155	int err = -ENOMEM;
 156
 157	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
 158		goto error_0;
 159
 160	clp->cl_nfs_mod = cl_init->nfs_mod;
 161	if (!try_module_get(clp->cl_nfs_mod->owner))
 162		goto error_dealloc;
 163
 164	clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
 165
 166	atomic_set(&clp->cl_count, 1);
 167	clp->cl_cons_state = NFS_CS_INITING;
 168
 169	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
 170	clp->cl_addrlen = cl_init->addrlen;
 171
 172	if (cl_init->hostname) {
 173		err = -ENOMEM;
 174		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
 175		if (!clp->cl_hostname)
 176			goto error_cleanup;
 177	}
 178
 179	INIT_LIST_HEAD(&clp->cl_superblocks);
 180	clp->cl_rpcclient = ERR_PTR(-EINVAL);
 181
 182	clp->cl_proto = cl_init->proto;
 183	clp->cl_net = get_net(cl_init->net);
 184
 185	cred = rpc_lookup_machine_cred("*");
 186	if (!IS_ERR(cred))
 187		clp->cl_machine_cred = cred;
 188	nfs_fscache_get_client_cookie(clp);
 189
 190	return clp;
 191
 192error_cleanup:
 193	put_nfs_version(clp->cl_nfs_mod);
 194error_dealloc:
 195	kfree(clp);
 196error_0:
 197	return ERR_PTR(err);
 198}
 199EXPORT_SYMBOL_GPL(nfs_alloc_client);
 200
 201#if IS_ENABLED(CONFIG_NFS_V4)
 202void nfs_cleanup_cb_ident_idr(struct net *net)
 203{
 204	struct nfs_net *nn = net_generic(net, nfs_net_id);
 205
 206	idr_destroy(&nn->cb_ident_idr);
 207}
 208
 209/* nfs_client_lock held */
 210static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 211{
 212	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 213
 214	if (clp->cl_cb_ident)
 215		idr_remove(&nn->cb_ident_idr, clp->cl_cb_ident);
 216}
 217
 218static void pnfs_init_server(struct nfs_server *server)
 219{
 220	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
 221}
 222
 223#else
 224void nfs_cleanup_cb_ident_idr(struct net *net)
 225{
 226}
 227
 228static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 229{
 230}
 231
 232static void pnfs_init_server(struct nfs_server *server)
 233{
 234}
 235
 236#endif /* CONFIG_NFS_V4 */
 237
 238/*
 239 * Destroy a shared client record
 240 */
 241void nfs_free_client(struct nfs_client *clp)
 242{
 243	dprintk("--> nfs_free_client(%u)\n", clp->rpc_ops->version);
 244
 245	nfs_fscache_release_client_cookie(clp);
 246
 247	/* -EIO all pending I/O */
 248	if (!IS_ERR(clp->cl_rpcclient))
 249		rpc_shutdown_client(clp->cl_rpcclient);
 250
 251	if (clp->cl_machine_cred != NULL)
 252		put_rpccred(clp->cl_machine_cred);
 253
 254	put_net(clp->cl_net);
 255	put_nfs_version(clp->cl_nfs_mod);
 256	kfree(clp->cl_hostname);
 257	kfree(clp->cl_acceptor);
 258	kfree(clp);
 259
 260	dprintk("<-- nfs_free_client()\n");
 261}
 262EXPORT_SYMBOL_GPL(nfs_free_client);
 263
 264/*
 265 * Release a reference to a shared client record
 266 */
 267void nfs_put_client(struct nfs_client *clp)
 268{
 269	struct nfs_net *nn;
 270
 271	if (!clp)
 272		return;
 273
 274	dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
 275	nn = net_generic(clp->cl_net, nfs_net_id);
 276
 277	if (atomic_dec_and_lock(&clp->cl_count, &nn->nfs_client_lock)) {
 278		list_del(&clp->cl_share_link);
 279		nfs_cb_idr_remove_locked(clp);
 280		spin_unlock(&nn->nfs_client_lock);
 281
 282		WARN_ON_ONCE(!list_empty(&clp->cl_superblocks));
 283
 284		clp->rpc_ops->free_client(clp);
 285	}
 286}
 287EXPORT_SYMBOL_GPL(nfs_put_client);
 288
 289/*
 290 * Find an nfs_client on the list that matches the initialisation data
 291 * that is supplied.
 292 */
 293static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
 294{
 295	struct nfs_client *clp;
 296	const struct sockaddr *sap = data->addr;
 297	struct nfs_net *nn = net_generic(data->net, nfs_net_id);
 298
 299	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 300	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 301		/* Don't match clients that failed to initialise properly */
 302		if (clp->cl_cons_state < 0)
 303			continue;
 304
 305		/* Different NFS versions cannot share the same nfs_client */
 306		if (clp->rpc_ops != data->nfs_mod->rpc_ops)
 307			continue;
 308
 309		if (clp->cl_proto != data->proto)
 310			continue;
 311		/* Match nfsv4 minorversion */
 312		if (clp->cl_minorversion != data->minorversion)
 313			continue;
 314		/* Match the full socket address */
 315		if (!rpc_cmp_addr_port(sap, clap))
 316			/* Match all xprt_switch full socket addresses */
 317			if (IS_ERR(clp->cl_rpcclient) ||
 318                            !rpc_clnt_xprt_switch_has_addr(clp->cl_rpcclient,
 319							   sap))
 320				continue;
 321
 322		atomic_inc(&clp->cl_count);
 323		return clp;
 324	}
 325	return NULL;
 326}
 327
 328static bool nfs_client_init_is_complete(const struct nfs_client *clp)
 329{
 330	return clp->cl_cons_state <= NFS_CS_READY;
 331}
 332
 333int nfs_wait_client_init_complete(const struct nfs_client *clp)
 334{
 335	return wait_event_killable(nfs_client_active_wq,
 336			nfs_client_init_is_complete(clp));
 337}
 338EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
 339
 340/*
 341 * Found an existing client.  Make sure it's ready before returning.
 342 */
 343static struct nfs_client *
 344nfs_found_client(const struct nfs_client_initdata *cl_init,
 345		 struct nfs_client *clp)
 346{
 347	int error;
 348
 349	error = nfs_wait_client_init_complete(clp);
 350	if (error < 0) {
 351		nfs_put_client(clp);
 352		return ERR_PTR(-ERESTARTSYS);
 353	}
 354
 355	if (clp->cl_cons_state < NFS_CS_READY) {
 356		error = clp->cl_cons_state;
 357		nfs_put_client(clp);
 358		return ERR_PTR(error);
 359	}
 360
 361	smp_rmb();
 362
 363	dprintk("<-- %s found nfs_client %p for %s\n",
 364		__func__, clp, cl_init->hostname ?: "");
 365	return clp;
 366}
 367
 368/*
 369 * Look up a client by IP address and protocol version
 370 * - creates a new record if one doesn't yet exist
 371 */
 372struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
 373{
 374	struct nfs_client *clp, *new = NULL;
 375	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
 376	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
 377
 378	if (cl_init->hostname == NULL) {
 379		WARN_ON(1);
 380		return NULL;
 381	}
 382
 383	dprintk("--> nfs_get_client(%s,v%u)\n",
 384		cl_init->hostname, rpc_ops->version);
 385
 386	/* see if the client already exists */
 387	do {
 388		spin_lock(&nn->nfs_client_lock);
 389
 390		clp = nfs_match_client(cl_init);
 391		if (clp) {
 392			spin_unlock(&nn->nfs_client_lock);
 393			if (new)
 394				new->rpc_ops->free_client(new);
 395			return nfs_found_client(cl_init, clp);
 396		}
 397		if (new) {
 398			list_add_tail(&new->cl_share_link,
 399					&nn->nfs_client_list);
 400			spin_unlock(&nn->nfs_client_lock);
 401			new->cl_flags = cl_init->init_flags;
 402			return rpc_ops->init_client(new, cl_init);
 403		}
 404
 405		spin_unlock(&nn->nfs_client_lock);
 406
 407		new = rpc_ops->alloc_client(cl_init);
 408	} while (!IS_ERR(new));
 409
 410	dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
 411		cl_init->hostname, PTR_ERR(new));
 412	return new;
 413}
 414EXPORT_SYMBOL_GPL(nfs_get_client);
 415
 416/*
 417 * Mark a server as ready or failed
 418 */
 419void nfs_mark_client_ready(struct nfs_client *clp, int state)
 420{
 421	smp_wmb();
 422	clp->cl_cons_state = state;
 423	wake_up_all(&nfs_client_active_wq);
 424}
 425EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
 426
 427/*
 428 * Initialise the timeout values for a connection
 429 */
 430void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 431				    int timeo, int retrans)
 432{
 433	to->to_initval = timeo * HZ / 10;
 434	to->to_retries = retrans;
 435
 436	switch (proto) {
 437	case XPRT_TRANSPORT_TCP:
 438	case XPRT_TRANSPORT_RDMA:
 439		if (retrans == NFS_UNSPEC_RETRANS)
 440			to->to_retries = NFS_DEF_TCP_RETRANS;
 441		if (timeo == NFS_UNSPEC_TIMEO || to->to_retries == 0)
 442			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
 443		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
 444			to->to_initval = NFS_MAX_TCP_TIMEOUT;
 445		to->to_increment = to->to_initval;
 446		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
 447		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
 448			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
 449		if (to->to_maxval < to->to_initval)
 450			to->to_maxval = to->to_initval;
 451		to->to_exponential = 0;
 452		break;
 453	case XPRT_TRANSPORT_UDP:
 454		if (retrans == NFS_UNSPEC_RETRANS)
 455			to->to_retries = NFS_DEF_UDP_RETRANS;
 456		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
 457			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
 458		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
 459			to->to_initval = NFS_MAX_UDP_TIMEOUT;
 460		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
 461		to->to_exponential = 1;
 462		break;
 463	default:
 464		BUG();
 465	}
 466}
 467EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
 468
 469/*
 470 * Create an RPC client handle
 471 */
 472int nfs_create_rpc_client(struct nfs_client *clp,
 473			  const struct nfs_client_initdata *cl_init,
 474			  rpc_authflavor_t flavor)
 475{
 476	struct rpc_clnt		*clnt = NULL;
 477	struct rpc_create_args args = {
 478		.net		= clp->cl_net,
 479		.protocol	= clp->cl_proto,
 480		.address	= (struct sockaddr *)&clp->cl_addr,
 481		.addrsize	= clp->cl_addrlen,
 482		.timeout	= cl_init->timeparms,
 483		.servername	= clp->cl_hostname,
 484		.nodename	= cl_init->nodename,
 485		.program	= &nfs_program,
 486		.version	= clp->rpc_ops->version,
 487		.authflavor	= flavor,
 488	};
 489
 490	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
 491		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
 492	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
 493		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
 494	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
 495		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
 496	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
 497		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
 498
 499	if (!IS_ERR(clp->cl_rpcclient))
 500		return 0;
 501
 502	clnt = rpc_create(&args);
 503	if (IS_ERR(clnt)) {
 504		dprintk("%s: cannot create RPC client. Error = %ld\n",
 505				__func__, PTR_ERR(clnt));
 506		return PTR_ERR(clnt);
 507	}
 508
 509	clp->cl_rpcclient = clnt;
 510	return 0;
 511}
 512EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
 513
 514/*
 515 * Version 2 or 3 client destruction
 516 */
 517static void nfs_destroy_server(struct nfs_server *server)
 518{
 519	if (server->nlm_host)
 520		nlmclnt_done(server->nlm_host);
 521}
 522
 523/*
 524 * Version 2 or 3 lockd setup
 525 */
 526static int nfs_start_lockd(struct nfs_server *server)
 527{
 528	struct nlm_host *host;
 529	struct nfs_client *clp = server->nfs_client;
 530	struct nlmclnt_initdata nlm_init = {
 531		.hostname	= clp->cl_hostname,
 532		.address	= (struct sockaddr *)&clp->cl_addr,
 533		.addrlen	= clp->cl_addrlen,
 534		.nfs_version	= clp->rpc_ops->version,
 535		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
 536					1 : 0,
 537		.net		= clp->cl_net,
 538	};
 539
 540	if (nlm_init.nfs_version > 3)
 541		return 0;
 542	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
 543			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
 544		return 0;
 545
 546	switch (clp->cl_proto) {
 547		default:
 548			nlm_init.protocol = IPPROTO_TCP;
 549			break;
 550		case XPRT_TRANSPORT_UDP:
 551			nlm_init.protocol = IPPROTO_UDP;
 552	}
 553
 554	host = nlmclnt_init(&nlm_init);
 555	if (IS_ERR(host))
 556		return PTR_ERR(host);
 557
 558	server->nlm_host = host;
 559	server->destroy = nfs_destroy_server;
 560	return 0;
 561}
 562
 563/*
 564 * Create a general RPC client
 565 */
 566int nfs_init_server_rpcclient(struct nfs_server *server,
 567		const struct rpc_timeout *timeo,
 568		rpc_authflavor_t pseudoflavour)
 569{
 570	struct nfs_client *clp = server->nfs_client;
 571
 572	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
 573							pseudoflavour);
 574	if (IS_ERR(server->client)) {
 575		dprintk("%s: couldn't create rpc_client!\n", __func__);
 576		return PTR_ERR(server->client);
 577	}
 578
 579	memcpy(&server->client->cl_timeout_default,
 580			timeo,
 581			sizeof(server->client->cl_timeout_default));
 582	server->client->cl_timeout = &server->client->cl_timeout_default;
 583	server->client->cl_softrtry = 0;
 584	if (server->flags & NFS_MOUNT_SOFT)
 585		server->client->cl_softrtry = 1;
 586
 587	return 0;
 588}
 589EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
 590
 591/**
 592 * nfs_init_client - Initialise an NFS2 or NFS3 client
 593 *
 594 * @clp: nfs_client to initialise
 595 * @cl_init: Initialisation parameters
 596 *
 597 * Returns pointer to an NFS client, or an ERR_PTR value.
 598 */
 599struct nfs_client *nfs_init_client(struct nfs_client *clp,
 600				   const struct nfs_client_initdata *cl_init)
 601{
 602	int error;
 603
 604	if (clp->cl_cons_state == NFS_CS_READY) {
 605		/* the client is already initialised */
 606		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
 607		return clp;
 608	}
 609
 610	/*
 611	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
 612	 * - RFC 2623, sec 2.3.2
 613	 */
 614	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
 615	if (error < 0)
 616		goto error;
 617	nfs_mark_client_ready(clp, NFS_CS_READY);
 618	return clp;
 619
 620error:
 621	nfs_mark_client_ready(clp, error);
 622	nfs_put_client(clp);
 623	dprintk("<-- nfs_init_client() = xerror %d\n", error);
 624	return ERR_PTR(error);
 625}
 626EXPORT_SYMBOL_GPL(nfs_init_client);
 627
 628/*
 629 * Create a version 2 or 3 client
 630 */
 631static int nfs_init_server(struct nfs_server *server,
 632			   const struct nfs_parsed_mount_data *data,
 633			   struct nfs_subversion *nfs_mod)
 634{
 635	struct rpc_timeout timeparms;
 636	struct nfs_client_initdata cl_init = {
 637		.hostname = data->nfs_server.hostname,
 638		.addr = (const struct sockaddr *)&data->nfs_server.address,
 639		.addrlen = data->nfs_server.addrlen,
 640		.nfs_mod = nfs_mod,
 641		.proto = data->nfs_server.protocol,
 642		.net = data->net,
 643		.timeparms = &timeparms,
 644	};
 645	struct nfs_client *clp;
 646	int error;
 647
 648	dprintk("--> nfs_init_server()\n");
 649
 650	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 651			data->timeo, data->retrans);
 652	if (data->flags & NFS_MOUNT_NORESVPORT)
 653		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 654
 655	/* Allocate or find a client reference we can use */
 656	clp = nfs_get_client(&cl_init);
 657	if (IS_ERR(clp)) {
 658		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
 659		return PTR_ERR(clp);
 660	}
 661
 662	server->nfs_client = clp;
 663
 664	/* Initialise the client representation from the mount data */
 665	server->flags = data->flags;
 666	server->options = data->options;
 667	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
 668		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
 669		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME;
 670
 671	if (data->rsize)
 672		server->rsize = nfs_block_size(data->rsize, NULL);
 673	if (data->wsize)
 674		server->wsize = nfs_block_size(data->wsize, NULL);
 675
 676	server->acregmin = data->acregmin * HZ;
 677	server->acregmax = data->acregmax * HZ;
 678	server->acdirmin = data->acdirmin * HZ;
 679	server->acdirmax = data->acdirmax * HZ;
 680
 681	/* Start lockd here, before we might error out */
 682	error = nfs_start_lockd(server);
 683	if (error < 0)
 684		goto error;
 685
 686	server->port = data->nfs_server.port;
 687	server->auth_info = data->auth_info;
 688
 689	error = nfs_init_server_rpcclient(server, &timeparms,
 690					  data->selected_flavor);
 691	if (error < 0)
 692		goto error;
 693
 694	/* Preserve the values of mount_server-related mount options */
 695	if (data->mount_server.addrlen) {
 696		memcpy(&server->mountd_address, &data->mount_server.address,
 697			data->mount_server.addrlen);
 698		server->mountd_addrlen = data->mount_server.addrlen;
 699	}
 700	server->mountd_version = data->mount_server.version;
 701	server->mountd_port = data->mount_server.port;
 702	server->mountd_protocol = data->mount_server.protocol;
 703
 704	server->namelen  = data->namlen;
 705	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
 706	return 0;
 707
 708error:
 709	server->nfs_client = NULL;
 710	nfs_put_client(clp);
 711	dprintk("<-- nfs_init_server() = xerror %d\n", error);
 712	return error;
 713}
 714
 715/*
 716 * Load up the server record from information gained in an fsinfo record
 717 */
 718static void nfs_server_set_fsinfo(struct nfs_server *server,
 719				  struct nfs_fsinfo *fsinfo)
 720{
 721	unsigned long max_rpc_payload;
 722
 723	/* Work out a lot of parameters */
 724	if (server->rsize == 0)
 725		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
 726	if (server->wsize == 0)
 727		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
 728
 729	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
 730		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
 731	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
 732		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
 733
 734	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
 735	if (server->rsize > max_rpc_payload)
 736		server->rsize = max_rpc_payload;
 737	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
 738		server->rsize = NFS_MAX_FILE_IO_SIZE;
 739	server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
 740
 741	server->backing_dev_info.name = "nfs";
 742	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
 743
 744	if (server->wsize > max_rpc_payload)
 745		server->wsize = max_rpc_payload;
 746	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
 747		server->wsize = NFS_MAX_FILE_IO_SIZE;
 748	server->wpages = (server->wsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
 749
 750	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
 751
 752	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
 753	if (server->dtsize > PAGE_SIZE * NFS_MAX_READDIR_PAGES)
 754		server->dtsize = PAGE_SIZE * NFS_MAX_READDIR_PAGES;
 755	if (server->dtsize > server->rsize)
 756		server->dtsize = server->rsize;
 757
 758	if (server->flags & NFS_MOUNT_NOAC) {
 759		server->acregmin = server->acregmax = 0;
 760		server->acdirmin = server->acdirmax = 0;
 761	}
 762
 763	server->maxfilesize = fsinfo->maxfilesize;
 764
 765	server->time_delta = fsinfo->time_delta;
 766
 767	server->clone_blksize = fsinfo->clone_blksize;
 768	/* We're airborne Set socket buffersize */
 769	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
 770}
 771
 772/*
 773 * Probe filesystem information, including the FSID on v2/v3
 774 */
 775int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
 776{
 777	struct nfs_fsinfo fsinfo;
 778	struct nfs_client *clp = server->nfs_client;
 779	int error;
 780
 781	dprintk("--> nfs_probe_fsinfo()\n");
 782
 783	if (clp->rpc_ops->set_capabilities != NULL) {
 784		error = clp->rpc_ops->set_capabilities(server, mntfh);
 785		if (error < 0)
 786			goto out_error;
 787	}
 788
 789	fsinfo.fattr = fattr;
 790	fsinfo.nlayouttypes = 0;
 791	memset(fsinfo.layouttype, 0, sizeof(fsinfo.layouttype));
 792	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
 793	if (error < 0)
 794		goto out_error;
 795
 796	nfs_server_set_fsinfo(server, &fsinfo);
 797
 798	/* Get some general file system info */
 799	if (server->namelen == 0) {
 800		struct nfs_pathconf pathinfo;
 801
 802		pathinfo.fattr = fattr;
 803		nfs_fattr_init(fattr);
 804
 805		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
 806			server->namelen = pathinfo.max_namelen;
 807	}
 808
 809	dprintk("<-- nfs_probe_fsinfo() = 0\n");
 810	return 0;
 811
 812out_error:
 813	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
 814	return error;
 815}
 816EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
 817
 818/*
 819 * Copy useful information when duplicating a server record
 820 */
 821void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
 822{
 823	target->flags = source->flags;
 824	target->rsize = source->rsize;
 825	target->wsize = source->wsize;
 826	target->acregmin = source->acregmin;
 827	target->acregmax = source->acregmax;
 828	target->acdirmin = source->acdirmin;
 829	target->acdirmax = source->acdirmax;
 830	target->caps = source->caps;
 831	target->options = source->options;
 832	target->auth_info = source->auth_info;
 833}
 834EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
 835
 836void nfs_server_insert_lists(struct nfs_server *server)
 837{
 838	struct nfs_client *clp = server->nfs_client;
 839	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 840
 841	spin_lock(&nn->nfs_client_lock);
 842	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
 843	list_add_tail(&server->master_link, &nn->nfs_volume_list);
 844	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
 845	spin_unlock(&nn->nfs_client_lock);
 846
 847}
 848EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
 849
 850void nfs_server_remove_lists(struct nfs_server *server)
 851{
 852	struct nfs_client *clp = server->nfs_client;
 853	struct nfs_net *nn;
 854
 855	if (clp == NULL)
 856		return;
 857	nn = net_generic(clp->cl_net, nfs_net_id);
 858	spin_lock(&nn->nfs_client_lock);
 859	list_del_rcu(&server->client_link);
 860	if (list_empty(&clp->cl_superblocks))
 861		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
 862	list_del(&server->master_link);
 863	spin_unlock(&nn->nfs_client_lock);
 864
 865	synchronize_rcu();
 866}
 867EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
 868
 869/*
 870 * Allocate and initialise a server record
 871 */
 872struct nfs_server *nfs_alloc_server(void)
 873{
 874	struct nfs_server *server;
 875
 876	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
 877	if (!server)
 878		return NULL;
 879
 880	server->client = server->client_acl = ERR_PTR(-EINVAL);
 881
 882	/* Zero out the NFS state stuff */
 883	INIT_LIST_HEAD(&server->client_link);
 884	INIT_LIST_HEAD(&server->master_link);
 885	INIT_LIST_HEAD(&server->delegations);
 886	INIT_LIST_HEAD(&server->layouts);
 887	INIT_LIST_HEAD(&server->state_owners_lru);
 888
 889	atomic_set(&server->active, 0);
 890
 891	server->io_stats = nfs_alloc_iostats();
 892	if (!server->io_stats) {
 893		kfree(server);
 894		return NULL;
 895	}
 896
 897	if (bdi_init(&server->backing_dev_info)) {
 898		nfs_free_iostats(server->io_stats);
 899		kfree(server);
 900		return NULL;
 901	}
 902
 903	ida_init(&server->openowner_id);
 904	ida_init(&server->lockowner_id);
 905	pnfs_init_server(server);
 906
 907	return server;
 908}
 909EXPORT_SYMBOL_GPL(nfs_alloc_server);
 910
 911/*
 912 * Free up a server record
 913 */
 914void nfs_free_server(struct nfs_server *server)
 915{
 916	dprintk("--> nfs_free_server()\n");
 917
 918	nfs_server_remove_lists(server);
 919
 920	if (server->destroy != NULL)
 921		server->destroy(server);
 922
 923	if (!IS_ERR(server->client_acl))
 924		rpc_shutdown_client(server->client_acl);
 925	if (!IS_ERR(server->client))
 926		rpc_shutdown_client(server->client);
 927
 928	nfs_put_client(server->nfs_client);
 929
 930	ida_destroy(&server->lockowner_id);
 931	ida_destroy(&server->openowner_id);
 932	nfs_free_iostats(server->io_stats);
 933	bdi_destroy(&server->backing_dev_info);
 934	kfree(server);
 935	nfs_release_automount_timer();
 936	dprintk("<-- nfs_free_server()\n");
 937}
 938EXPORT_SYMBOL_GPL(nfs_free_server);
 939
 940/*
 941 * Create a version 2 or 3 volume record
 942 * - keyed on server and FSID
 943 */
 944struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
 945				     struct nfs_subversion *nfs_mod)
 946{
 947	struct nfs_server *server;
 948	struct nfs_fattr *fattr;
 949	int error;
 950
 951	server = nfs_alloc_server();
 952	if (!server)
 953		return ERR_PTR(-ENOMEM);
 954
 955	error = -ENOMEM;
 956	fattr = nfs_alloc_fattr();
 957	if (fattr == NULL)
 958		goto error;
 959
 960	/* Get a client representation */
 961	error = nfs_init_server(server, mount_info->parsed, nfs_mod);
 962	if (error < 0)
 963		goto error;
 964
 965	/* Probe the root fh to retrieve its FSID */
 966	error = nfs_probe_fsinfo(server, mount_info->mntfh, fattr);
 967	if (error < 0)
 968		goto error;
 969	if (server->nfs_client->rpc_ops->version == 3) {
 970		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
 971			server->namelen = NFS3_MAXNAMLEN;
 972		if (!(mount_info->parsed->flags & NFS_MOUNT_NORDIRPLUS))
 973			server->caps |= NFS_CAP_READDIRPLUS;
 974	} else {
 975		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
 976			server->namelen = NFS2_MAXNAMLEN;
 977	}
 978
 979	if (!(fattr->valid & NFS_ATTR_FATTR)) {
 980		error = nfs_mod->rpc_ops->getattr(server, mount_info->mntfh, fattr, NULL);
 981		if (error < 0) {
 982			dprintk("nfs_create_server: getattr error = %d\n", -error);
 983			goto error;
 984		}
 985	}
 986	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
 987
 988	dprintk("Server FSID: %llx:%llx\n",
 989		(unsigned long long) server->fsid.major,
 990		(unsigned long long) server->fsid.minor);
 991
 992	nfs_server_insert_lists(server);
 993	server->mount_time = jiffies;
 994	nfs_free_fattr(fattr);
 995	return server;
 996
 997error:
 998	nfs_free_fattr(fattr);
 999	nfs_free_server(server);
1000	return ERR_PTR(error);
1001}
1002EXPORT_SYMBOL_GPL(nfs_create_server);
1003
1004/*
1005 * Clone an NFS2, NFS3 or NFS4 server record
1006 */
1007struct nfs_server *nfs_clone_server(struct nfs_server *source,
1008				    struct nfs_fh *fh,
1009				    struct nfs_fattr *fattr,
1010				    rpc_authflavor_t flavor)
1011{
1012	struct nfs_server *server;
1013	struct nfs_fattr *fattr_fsinfo;
1014	int error;
1015
1016	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1017		(unsigned long long) fattr->fsid.major,
1018		(unsigned long long) fattr->fsid.minor);
1019
1020	server = nfs_alloc_server();
1021	if (!server)
1022		return ERR_PTR(-ENOMEM);
1023
1024	error = -ENOMEM;
1025	fattr_fsinfo = nfs_alloc_fattr();
1026	if (fattr_fsinfo == NULL)
1027		goto out_free_server;
1028
1029	/* Copy data from the source */
1030	server->nfs_client = source->nfs_client;
1031	server->destroy = source->destroy;
1032	atomic_inc(&server->nfs_client->cl_count);
1033	nfs_server_copy_userdata(server, source);
1034
1035	server->fsid = fattr->fsid;
1036
1037	error = nfs_init_server_rpcclient(server,
1038			source->client->cl_timeout,
1039			flavor);
1040	if (error < 0)
1041		goto out_free_server;
1042
1043	/* probe the filesystem info for this server filesystem */
1044	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1045	if (error < 0)
1046		goto out_free_server;
1047
1048	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1049		server->namelen = NFS4_MAXNAMLEN;
1050
1051	dprintk("Cloned FSID: %llx:%llx\n",
1052		(unsigned long long) server->fsid.major,
1053		(unsigned long long) server->fsid.minor);
1054
1055	error = nfs_start_lockd(server);
1056	if (error < 0)
1057		goto out_free_server;
1058
1059	nfs_server_insert_lists(server);
1060	server->mount_time = jiffies;
1061
1062	nfs_free_fattr(fattr_fsinfo);
1063	dprintk("<-- nfs_clone_server() = %p\n", server);
1064	return server;
1065
1066out_free_server:
1067	nfs_free_fattr(fattr_fsinfo);
1068	nfs_free_server(server);
1069	dprintk("<-- nfs_clone_server() = error %d\n", error);
1070	return ERR_PTR(error);
1071}
1072EXPORT_SYMBOL_GPL(nfs_clone_server);
1073
1074void nfs_clients_init(struct net *net)
1075{
1076	struct nfs_net *nn = net_generic(net, nfs_net_id);
1077
1078	INIT_LIST_HEAD(&nn->nfs_client_list);
1079	INIT_LIST_HEAD(&nn->nfs_volume_list);
1080#if IS_ENABLED(CONFIG_NFS_V4)
1081	idr_init(&nn->cb_ident_idr);
1082#endif
1083	spin_lock_init(&nn->nfs_client_lock);
1084	nn->boot_time = ktime_get_real();
1085}
1086
1087#ifdef CONFIG_PROC_FS
1088static int nfs_server_list_open(struct inode *inode, struct file *file);
1089static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1090static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1091static void nfs_server_list_stop(struct seq_file *p, void *v);
1092static int nfs_server_list_show(struct seq_file *m, void *v);
1093
1094static const struct seq_operations nfs_server_list_ops = {
1095	.start	= nfs_server_list_start,
1096	.next	= nfs_server_list_next,
1097	.stop	= nfs_server_list_stop,
1098	.show	= nfs_server_list_show,
1099};
1100
1101static const struct file_operations nfs_server_list_fops = {
1102	.open		= nfs_server_list_open,
1103	.read		= seq_read,
1104	.llseek		= seq_lseek,
1105	.release	= seq_release_net,
1106};
1107
1108static int nfs_volume_list_open(struct inode *inode, struct file *file);
1109static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1110static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1111static void nfs_volume_list_stop(struct seq_file *p, void *v);
1112static int nfs_volume_list_show(struct seq_file *m, void *v);
1113
1114static const struct seq_operations nfs_volume_list_ops = {
1115	.start	= nfs_volume_list_start,
1116	.next	= nfs_volume_list_next,
1117	.stop	= nfs_volume_list_stop,
1118	.show	= nfs_volume_list_show,
1119};
1120
1121static const struct file_operations nfs_volume_list_fops = {
1122	.open		= nfs_volume_list_open,
1123	.read		= seq_read,
1124	.llseek		= seq_lseek,
1125	.release	= seq_release_net,
1126};
1127
1128/*
1129 * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1130 * we're dealing
1131 */
1132static int nfs_server_list_open(struct inode *inode, struct file *file)
1133{
1134	return seq_open_net(inode, file, &nfs_server_list_ops,
1135			   sizeof(struct seq_net_private));
1136}
1137
1138/*
1139 * set up the iterator to start reading from the server list and return the first item
1140 */
1141static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1142				__acquires(&nn->nfs_client_lock)
1143{
1144	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1145
1146	/* lock the list against modification */
1147	spin_lock(&nn->nfs_client_lock);
1148	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1149}
1150
1151/*
1152 * move to next server
1153 */
1154static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1155{
1156	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1157
1158	return seq_list_next(v, &nn->nfs_client_list, pos);
1159}
1160
1161/*
1162 * clean up after reading from the transports list
1163 */
1164static void nfs_server_list_stop(struct seq_file *p, void *v)
1165				__releases(&nn->nfs_client_lock)
1166{
1167	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1168
1169	spin_unlock(&nn->nfs_client_lock);
1170}
1171
1172/*
1173 * display a header line followed by a load of call lines
1174 */
1175static int nfs_server_list_show(struct seq_file *m, void *v)
1176{
1177	struct nfs_client *clp;
1178	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1179
1180	/* display header on line 1 */
1181	if (v == &nn->nfs_client_list) {
1182		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1183		return 0;
1184	}
1185
1186	/* display one transport per line on subsequent lines */
1187	clp = list_entry(v, struct nfs_client, cl_share_link);
1188
1189	/* Check if the client is initialized */
1190	if (clp->cl_cons_state != NFS_CS_READY)
1191		return 0;
1192
1193	rcu_read_lock();
1194	seq_printf(m, "v%u %s %s %3d %s\n",
1195		   clp->rpc_ops->version,
1196		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1197		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1198		   atomic_read(&clp->cl_count),
1199		   clp->cl_hostname);
1200	rcu_read_unlock();
1201
1202	return 0;
1203}
1204
1205/*
1206 * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1207 */
1208static int nfs_volume_list_open(struct inode *inode, struct file *file)
1209{
1210	return seq_open_net(inode, file, &nfs_volume_list_ops,
1211			   sizeof(struct seq_net_private));
1212}
1213
1214/*
1215 * set up the iterator to start reading from the volume list and return the first item
1216 */
1217static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1218				__acquires(&nn->nfs_client_lock)
1219{
1220	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1221
1222	/* lock the list against modification */
1223	spin_lock(&nn->nfs_client_lock);
1224	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1225}
1226
1227/*
1228 * move to next volume
1229 */
1230static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1231{
1232	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1233
1234	return seq_list_next(v, &nn->nfs_volume_list, pos);
1235}
1236
1237/*
1238 * clean up after reading from the transports list
1239 */
1240static void nfs_volume_list_stop(struct seq_file *p, void *v)
1241				__releases(&nn->nfs_client_lock)
1242{
1243	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1244
1245	spin_unlock(&nn->nfs_client_lock);
1246}
1247
1248/*
1249 * display a header line followed by a load of call lines
1250 */
1251static int nfs_volume_list_show(struct seq_file *m, void *v)
1252{
1253	struct nfs_server *server;
1254	struct nfs_client *clp;
1255	char dev[13];	// 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1256	char fsid[34];	// 2 * 16 for %llx, 1 for ':', 1 for '\0'
1257	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1258
1259	/* display header on line 1 */
1260	if (v == &nn->nfs_volume_list) {
1261		seq_puts(m, "NV SERVER   PORT DEV          FSID"
1262			    "                              FSC\n");
1263		return 0;
1264	}
1265	/* display one transport per line on subsequent lines */
1266	server = list_entry(v, struct nfs_server, master_link);
1267	clp = server->nfs_client;
1268
1269	snprintf(dev, sizeof(dev), "%u:%u",
1270		 MAJOR(server->s_dev), MINOR(server->s_dev));
1271
1272	snprintf(fsid, sizeof(fsid), "%llx:%llx",
1273		 (unsigned long long) server->fsid.major,
1274		 (unsigned long long) server->fsid.minor);
1275
1276	rcu_read_lock();
1277	seq_printf(m, "v%u %s %s %-12s %-33s %s\n",
1278		   clp->rpc_ops->version,
1279		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1280		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1281		   dev,
1282		   fsid,
1283		   nfs_server_fscache_state(server));
1284	rcu_read_unlock();
1285
1286	return 0;
1287}
1288
1289int nfs_fs_proc_net_init(struct net *net)
1290{
1291	struct nfs_net *nn = net_generic(net, nfs_net_id);
1292	struct proc_dir_entry *p;
1293
1294	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1295	if (!nn->proc_nfsfs)
1296		goto error_0;
1297
1298	/* a file of servers with which we're dealing */
1299	p = proc_create("servers", S_IFREG|S_IRUGO,
1300			nn->proc_nfsfs, &nfs_server_list_fops);
1301	if (!p)
1302		goto error_1;
1303
1304	/* a file of volumes that we have mounted */
1305	p = proc_create("volumes", S_IFREG|S_IRUGO,
1306			nn->proc_nfsfs, &nfs_volume_list_fops);
1307	if (!p)
1308		goto error_1;
1309	return 0;
1310
1311error_1:
1312	remove_proc_subtree("nfsfs", net->proc_net);
1313error_0:
1314	return -ENOMEM;
1315}
1316
1317void nfs_fs_proc_net_exit(struct net *net)
1318{
1319	remove_proc_subtree("nfsfs", net->proc_net);
1320}
1321
1322/*
1323 * initialise the /proc/fs/nfsfs/ directory
1324 */
1325int __init nfs_fs_proc_init(void)
1326{
1327	if (!proc_mkdir("fs/nfsfs", NULL))
1328		goto error_0;
1329
1330	/* a file of servers with which we're dealing */
1331	if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1332		goto error_1;
1333
1334	/* a file of volumes that we have mounted */
1335	if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1336		goto error_1;
1337
1338	return 0;
1339error_1:
1340	remove_proc_subtree("fs/nfsfs", NULL);
1341error_0:
1342	return -ENOMEM;
1343}
1344
1345/*
1346 * clean up the /proc/fs/nfsfs/ directory
1347 */
1348void nfs_fs_proc_exit(void)
1349{
1350	remove_proc_subtree("fs/nfsfs", NULL);
1351}
1352
1353#endif /* CONFIG_PROC_FS */