client.c

   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#include <linux/nfslocalio.h>
  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_RWLOCK(nfs_version_lock);
  59
  60static struct nfs_subversion *nfs_version_mods[5] = {
  61	[2] = NULL,
  62	[3] = NULL,
  63	[4] = NULL,
  64};
  65
  66/*
  67 * RPC cruft for NFS
  68 */
  69static const struct rpc_version *nfs_version[5] = {
  70	[2] = NULL,
  71	[3] = NULL,
  72	[4] = NULL,
  73};
  74
  75const struct rpc_program nfs_program = {
  76	.name			= "nfs",
  77	.number			= NFS_PROGRAM,
  78	.nrvers			= ARRAY_SIZE(nfs_version),
  79	.version		= nfs_version,
  80	.pipe_dir_name		= NFS_PIPE_DIRNAME,
  81};
  82
  83static struct nfs_subversion *__find_nfs_version(unsigned int version)
  84{
  85	struct nfs_subversion *nfs;
  86
  87	read_lock(&nfs_version_lock);
  88	nfs = nfs_version_mods[version];
  89	read_unlock(&nfs_version_lock);
  90	return nfs;
  91}
  92
  93struct nfs_subversion *find_nfs_version(unsigned int version)
  94{
  95	struct nfs_subversion *nfs = __find_nfs_version(version);
  96
  97	if (!nfs && request_module("nfsv%d", version) == 0)
  98		nfs = __find_nfs_version(version);
  99
 100	if (!nfs)
 101		return ERR_PTR(-EPROTONOSUPPORT);
 102
 103	if (!get_nfs_version(nfs))
 104		return ERR_PTR(-EAGAIN);
 105
 106	return nfs;
 107}
 108
 109int get_nfs_version(struct nfs_subversion *nfs)
 110{
 111	return try_module_get(nfs->owner);
 112}
 113EXPORT_SYMBOL_GPL(get_nfs_version);
 114
 115void put_nfs_version(struct nfs_subversion *nfs)
 116{
 117	module_put(nfs->owner);
 118}
 119
 120void register_nfs_version(struct nfs_subversion *nfs)
 121{
 122	write_lock(&nfs_version_lock);
 123
 124	nfs_version_mods[nfs->rpc_ops->version] = nfs;
 125	nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
 126
 127	write_unlock(&nfs_version_lock);
 128}
 129EXPORT_SYMBOL_GPL(register_nfs_version);
 130
 131void unregister_nfs_version(struct nfs_subversion *nfs)
 132{
 133	write_lock(&nfs_version_lock);
 134
 135	nfs_version[nfs->rpc_ops->version] = NULL;
 136	nfs_version_mods[nfs->rpc_ops->version] = NULL;
 137
 138	write_unlock(&nfs_version_lock);
 139}
 140EXPORT_SYMBOL_GPL(unregister_nfs_version);
 141
 142/*
 143 * Allocate a shared client record
 144 *
 145 * Since these are allocated/deallocated very rarely, we don't
 146 * bother putting them in a slab cache...
 147 */
 148struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 149{
 150	struct nfs_client *clp;
 151	int err = -ENOMEM;
 152
 153	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
 154		goto error_0;
 155
 156	clp->cl_minorversion = cl_init->minorversion;
 157	clp->cl_nfs_mod = cl_init->nfs_mod;
 158	if (!get_nfs_version(clp->cl_nfs_mod))
 159		goto error_dealloc;
 160
 161	clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
 162
 163	refcount_set(&clp->cl_count, 1);
 164	clp->cl_cons_state = NFS_CS_INITING;
 165
 166	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
 167	clp->cl_addrlen = cl_init->addrlen;
 168
 169	if (cl_init->hostname) {
 170		err = -ENOMEM;
 171		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
 172		if (!clp->cl_hostname)
 173			goto error_cleanup;
 174	}
 175
 176	INIT_LIST_HEAD(&clp->cl_superblocks);
 177	clp->cl_rpcclient = ERR_PTR(-EINVAL);
 178
 179	clp->cl_flags = cl_init->init_flags;
 180	clp->cl_proto = cl_init->proto;
 181	clp->cl_nconnect = cl_init->nconnect;
 182	clp->cl_max_connect = cl_init->max_connect ? cl_init->max_connect : 1;
 183	clp->cl_net = get_net_track(cl_init->net, &clp->cl_ns_tracker, GFP_KERNEL);
 184
 185#if IS_ENABLED(CONFIG_NFS_LOCALIO)
 186	seqlock_init(&clp->cl_boot_lock);
 187	ktime_get_real_ts64(&clp->cl_nfssvc_boot);
 188	nfs_uuid_init(&clp->cl_uuid);
 189	INIT_WORK(&clp->cl_local_probe_work, nfs_local_probe_async_work);
 190#endif /* CONFIG_NFS_LOCALIO */
 191
 192	clp->cl_principal = "*";
 193	clp->cl_xprtsec = cl_init->xprtsec;
 194	return clp;
 195
 196error_cleanup:
 197	put_nfs_version(clp->cl_nfs_mod);
 198error_dealloc:
 199	kfree(clp);
 200error_0:
 201	return ERR_PTR(err);
 202}
 203EXPORT_SYMBOL_GPL(nfs_alloc_client);
 204
 205#if IS_ENABLED(CONFIG_NFS_V4)
 206static void nfs_cleanup_cb_ident_idr(struct net *net)
 207{
 208	struct nfs_net *nn = net_generic(net, nfs_net_id);
 209
 210	idr_destroy(&nn->cb_ident_idr);
 211}
 212
 213/* nfs_client_lock held */
 214static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 215{
 216	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 217
 218	if (clp->cl_cb_ident)
 219		idr_remove(&nn->cb_ident_idr, clp->cl_cb_ident);
 220}
 221
 222static void pnfs_init_server(struct nfs_server *server)
 223{
 224	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
 225}
 226
 227#else
 228static void nfs_cleanup_cb_ident_idr(struct net *net)
 229{
 230}
 231
 232static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 233{
 234}
 235
 236static void pnfs_init_server(struct nfs_server *server)
 237{
 238}
 239
 240#endif /* CONFIG_NFS_V4 */
 241
 242/*
 243 * Destroy a shared client record
 244 */
 245void nfs_free_client(struct nfs_client *clp)
 246{
 247	nfs_localio_disable_client(clp);
 248
 249	/* -EIO all pending I/O */
 250	if (!IS_ERR(clp->cl_rpcclient))
 251		rpc_shutdown_client(clp->cl_rpcclient);
 252
 253	put_net_track(clp->cl_net, &clp->cl_ns_tracker);
 254	put_nfs_version(clp->cl_nfs_mod);
 255	kfree(clp->cl_hostname);
 256	kfree(clp->cl_acceptor);
 257	kfree_rcu(clp, rcu);
 258}
 259EXPORT_SYMBOL_GPL(nfs_free_client);
 260
 261/*
 262 * Release a reference to a shared client record
 263 */
 264void nfs_put_client(struct nfs_client *clp)
 265{
 266	struct nfs_net *nn;
 267
 268	if (!clp)
 269		return;
 270
 271	nn = net_generic(clp->cl_net, nfs_net_id);
 272
 273	if (refcount_dec_and_lock(&clp->cl_count, &nn->nfs_client_lock)) {
 274		list_del(&clp->cl_share_link);
 275		nfs_cb_idr_remove_locked(clp);
 276		spin_unlock(&nn->nfs_client_lock);
 277
 278		WARN_ON_ONCE(!list_empty(&clp->cl_superblocks));
 279
 280		clp->rpc_ops->free_client(clp);
 281	}
 282}
 283EXPORT_SYMBOL_GPL(nfs_put_client);
 284
 285/*
 286 * Find an nfs_client on the list that matches the initialisation data
 287 * that is supplied.
 288 */
 289static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
 290{
 291	struct nfs_client *clp;
 292	const struct sockaddr *sap = (struct sockaddr *)data->addr;
 293	struct nfs_net *nn = net_generic(data->net, nfs_net_id);
 294	int error;
 295
 296again:
 297	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 298	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 299		/* Don't match clients that failed to initialise properly */
 300		if (clp->cl_cons_state < 0)
 301			continue;
 302
 303		/* If a client is still initializing then we need to wait */
 304		if (clp->cl_cons_state > NFS_CS_READY) {
 305			refcount_inc(&clp->cl_count);
 306			spin_unlock(&nn->nfs_client_lock);
 307			error = nfs_wait_client_init_complete(clp);
 308			nfs_put_client(clp);
 309			spin_lock(&nn->nfs_client_lock);
 310			if (error < 0)
 311				return ERR_PTR(error);
 312			goto again;
 313		}
 314
 315		/* Different NFS versions cannot share the same nfs_client */
 316		if (clp->rpc_ops != data->nfs_mod->rpc_ops)
 317			continue;
 318
 319		if (clp->cl_proto != data->proto)
 320			continue;
 321		/* Match nfsv4 minorversion */
 322		if (clp->cl_minorversion != data->minorversion)
 323			continue;
 324
 325		/* Match request for a dedicated DS */
 326		if (test_bit(NFS_CS_DS, &data->init_flags) !=
 327		    test_bit(NFS_CS_DS, &clp->cl_flags))
 328			continue;
 329
 330		/* Match the full socket address */
 331		if (!rpc_cmp_addr_port(sap, clap))
 332			/* Match all xprt_switch full socket addresses */
 333			if (IS_ERR(clp->cl_rpcclient) ||
 334                            !rpc_clnt_xprt_switch_has_addr(clp->cl_rpcclient,
 335							   sap))
 336				continue;
 337
 338		/* Match the xprt security policy */
 339		if (clp->cl_xprtsec.policy != data->xprtsec.policy)
 340			continue;
 341		if (clp->cl_xprtsec.policy == RPC_XPRTSEC_TLS_X509) {
 342			if (clp->cl_xprtsec.cert_serial !=
 343			    data->xprtsec.cert_serial)
 344				continue;
 345			if (clp->cl_xprtsec.privkey_serial !=
 346			    data->xprtsec.privkey_serial)
 347				continue;
 348		}
 349
 350		refcount_inc(&clp->cl_count);
 351		return clp;
 352	}
 353	return NULL;
 354}
 355
 356/*
 357 * Return true if @clp is done initializing, false if still working on it.
 358 *
 359 * Use nfs_client_init_status to check if it was successful.
 360 */
 361bool nfs_client_init_is_complete(const struct nfs_client *clp)
 362{
 363	return clp->cl_cons_state <= NFS_CS_READY;
 364}
 365EXPORT_SYMBOL_GPL(nfs_client_init_is_complete);
 366
 367/*
 368 * Return 0 if @clp was successfully initialized, -errno otherwise.
 369 *
 370 * This must be called *after* nfs_client_init_is_complete() returns true,
 371 * otherwise it will pop WARN_ON_ONCE and return -EINVAL
 372 */
 373int nfs_client_init_status(const struct nfs_client *clp)
 374{
 375	/* called without checking nfs_client_init_is_complete */
 376	if (clp->cl_cons_state > NFS_CS_READY) {
 377		WARN_ON_ONCE(1);
 378		return -EINVAL;
 379	}
 380	return clp->cl_cons_state;
 381}
 382EXPORT_SYMBOL_GPL(nfs_client_init_status);
 383
 384int nfs_wait_client_init_complete(const struct nfs_client *clp)
 385{
 386	return wait_event_killable(nfs_client_active_wq,
 387			nfs_client_init_is_complete(clp));
 388}
 389EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
 390
 391/*
 392 * Found an existing client.  Make sure it's ready before returning.
 393 */
 394static struct nfs_client *
 395nfs_found_client(const struct nfs_client_initdata *cl_init,
 396		 struct nfs_client *clp)
 397{
 398	int error;
 399
 400	error = nfs_wait_client_init_complete(clp);
 401	if (error < 0) {
 402		nfs_put_client(clp);
 403		return ERR_PTR(-ERESTARTSYS);
 404	}
 405
 406	if (clp->cl_cons_state < NFS_CS_READY) {
 407		error = clp->cl_cons_state;
 408		nfs_put_client(clp);
 409		return ERR_PTR(error);
 410	}
 411
 412	smp_rmb();
 413	return clp;
 414}
 415
 416/*
 417 * Look up a client by IP address and protocol version
 418 * - creates a new record if one doesn't yet exist
 419 */
 420struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
 421{
 422	struct nfs_client *clp, *new = NULL;
 423	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
 424	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
 425
 426	if (cl_init->hostname == NULL) {
 427		WARN_ON(1);
 428		return ERR_PTR(-EINVAL);
 429	}
 430
 431	/* see if the client already exists */
 432	do {
 433		spin_lock(&nn->nfs_client_lock);
 434
 435		clp = nfs_match_client(cl_init);
 436		if (clp) {
 437			spin_unlock(&nn->nfs_client_lock);
 438			if (new)
 439				new->rpc_ops->free_client(new);
 440			if (IS_ERR(clp))
 441				return clp;
 442			return nfs_found_client(cl_init, clp);
 443		}
 444		if (new) {
 445			list_add_tail(&new->cl_share_link,
 446					&nn->nfs_client_list);
 447			spin_unlock(&nn->nfs_client_lock);
 448			new = rpc_ops->init_client(new, cl_init);
 449			if (!IS_ERR(new))
 450				 nfs_local_probe_async(new);
 451			return new;
 452		}
 453
 454		spin_unlock(&nn->nfs_client_lock);
 455
 456		new = rpc_ops->alloc_client(cl_init);
 457	} while (!IS_ERR(new));
 458
 459	return new;
 460}
 461EXPORT_SYMBOL_GPL(nfs_get_client);
 462
 463/*
 464 * Mark a server as ready or failed
 465 */
 466void nfs_mark_client_ready(struct nfs_client *clp, int state)
 467{
 468	smp_wmb();
 469	clp->cl_cons_state = state;
 470	wake_up_all(&nfs_client_active_wq);
 471}
 472EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
 473
 474/*
 475 * Initialise the timeout values for a connection
 476 */
 477void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 478				    int timeo, int retrans)
 479{
 480	to->to_initval = timeo * HZ / 10;
 481	to->to_retries = retrans;
 482
 483	switch (proto) {
 484	case XPRT_TRANSPORT_TCP:
 485	case XPRT_TRANSPORT_TCP_TLS:
 486	case XPRT_TRANSPORT_RDMA:
 487		if (retrans == NFS_UNSPEC_RETRANS)
 488			to->to_retries = NFS_DEF_TCP_RETRANS;
 489		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
 490			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
 491		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
 492			to->to_initval = NFS_MAX_TCP_TIMEOUT;
 493		to->to_increment = to->to_initval;
 494		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
 495		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
 496			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
 497		if (to->to_maxval < to->to_initval)
 498			to->to_maxval = to->to_initval;
 499		to->to_exponential = 0;
 500		break;
 501	case XPRT_TRANSPORT_UDP:
 502		if (retrans == NFS_UNSPEC_RETRANS)
 503			to->to_retries = NFS_DEF_UDP_RETRANS;
 504		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
 505			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
 506		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
 507			to->to_initval = NFS_MAX_UDP_TIMEOUT;
 508		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
 509		to->to_exponential = 1;
 510		break;
 511	default:
 512		BUG();
 513	}
 514}
 515EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
 516
 517/*
 518 * Create an RPC client handle
 519 */
 520int nfs_create_rpc_client(struct nfs_client *clp,
 521			  const struct nfs_client_initdata *cl_init,
 522			  rpc_authflavor_t flavor)
 523{
 524	struct nfs_net		*nn = net_generic(clp->cl_net, nfs_net_id);
 525	struct rpc_clnt		*clnt = NULL;
 526	struct rpc_create_args args = {
 527		.net		= clp->cl_net,
 528		.protocol	= clp->cl_proto,
 529		.nconnect	= clp->cl_nconnect,
 530		.address	= (struct sockaddr *)&clp->cl_addr,
 531		.addrsize	= clp->cl_addrlen,
 532		.timeout	= cl_init->timeparms,
 533		.servername	= clp->cl_hostname,
 534		.nodename	= cl_init->nodename,
 535		.program	= &nfs_program,
 536		.stats		= &nn->rpcstats,
 537		.version	= clp->rpc_ops->version,
 538		.authflavor	= flavor,
 539		.cred		= cl_init->cred,
 540		.xprtsec	= cl_init->xprtsec,
 541		.connect_timeout = cl_init->connect_timeout,
 542		.reconnect_timeout = cl_init->reconnect_timeout,
 543	};
 544
 545	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
 546		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
 547	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
 548		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
 549	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
 550		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
 551	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
 552		args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
 553	if (test_bit(NFS_CS_NOPING, &clp->cl_flags))
 554		args.flags |= RPC_CLNT_CREATE_NOPING;
 555	if (test_bit(NFS_CS_REUSEPORT, &clp->cl_flags))
 556		args.flags |= RPC_CLNT_CREATE_REUSEPORT;
 557	if (test_bit(NFS_CS_NETUNREACH_FATAL, &clp->cl_flags))
 558		args.flags |= RPC_CLNT_CREATE_NETUNREACH_FATAL;
 559
 560	if (!IS_ERR(clp->cl_rpcclient))
 561		return 0;
 562
 563	clnt = rpc_create(&args);
 564	if (IS_ERR(clnt)) {
 565		dprintk("%s: cannot create RPC client. Error = %ld\n",
 566				__func__, PTR_ERR(clnt));
 567		return PTR_ERR(clnt);
 568	}
 569
 570	clnt->cl_principal = clp->cl_principal;
 571	clp->cl_rpcclient = clnt;
 572	clnt->cl_max_connect = clp->cl_max_connect;
 573	return 0;
 574}
 575EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
 576
 577/*
 578 * Version 2 or 3 client destruction
 579 */
 580static void nfs_destroy_server(struct nfs_server *server)
 581{
 582	if (server->nlm_host)
 583		nlmclnt_done(server->nlm_host);
 584}
 585
 586/*
 587 * Version 2 or 3 lockd setup
 588 */
 589static int nfs_start_lockd(struct nfs_server *server)
 590{
 591	struct nlm_host *host;
 592	struct nfs_client *clp = server->nfs_client;
 593	struct nlmclnt_initdata nlm_init = {
 594		.hostname	= clp->cl_hostname,
 595		.address	= (struct sockaddr *)&clp->cl_addr,
 596		.addrlen	= clp->cl_addrlen,
 597		.nfs_version	= clp->rpc_ops->version,
 598		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
 599					1 : 0,
 600		.net		= clp->cl_net,
 601		.nlmclnt_ops 	= clp->cl_nfs_mod->rpc_ops->nlmclnt_ops,
 602		.cred		= server->cred,
 603	};
 604
 605	if (nlm_init.nfs_version > 3)
 606		return 0;
 607	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
 608			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
 609		return 0;
 610
 611	switch (clp->cl_proto) {
 612		default:
 613			nlm_init.protocol = IPPROTO_TCP;
 614			break;
 615#ifndef CONFIG_NFS_DISABLE_UDP_SUPPORT
 616		case XPRT_TRANSPORT_UDP:
 617			nlm_init.protocol = IPPROTO_UDP;
 618#endif
 619	}
 620
 621	host = nlmclnt_init(&nlm_init);
 622	if (IS_ERR(host))
 623		return PTR_ERR(host);
 624
 625	server->nlm_host = host;
 626	server->destroy = nfs_destroy_server;
 627	nfs_sysfs_link_rpc_client(server, nlmclnt_rpc_clnt(host), NULL);
 628	return 0;
 629}
 630
 631/*
 632 * Create a general RPC client
 633 */
 634int nfs_init_server_rpcclient(struct nfs_server *server,
 635		const struct rpc_timeout *timeo,
 636		rpc_authflavor_t pseudoflavour)
 637{
 638	struct nfs_client *clp = server->nfs_client;
 639
 640	server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
 641							pseudoflavour);
 642	if (IS_ERR(server->client)) {
 643		dprintk("%s: couldn't create rpc_client!\n", __func__);
 644		return PTR_ERR(server->client);
 645	}
 646
 647	memcpy(&server->client->cl_timeout_default,
 648			timeo,
 649			sizeof(server->client->cl_timeout_default));
 650	server->client->cl_timeout = &server->client->cl_timeout_default;
 651	server->client->cl_softrtry = 0;
 652	if (server->flags & NFS_MOUNT_SOFTERR)
 653		server->client->cl_softerr = 1;
 654	if (server->flags & NFS_MOUNT_SOFT)
 655		server->client->cl_softrtry = 1;
 656
 657	nfs_sysfs_link_rpc_client(server, server->client, NULL);
 658	return 0;
 659}
 660EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
 661
 662/**
 663 * nfs_init_client - Initialise an NFS2 or NFS3 client
 664 *
 665 * @clp: nfs_client to initialise
 666 * @cl_init: Initialisation parameters
 667 *
 668 * Returns pointer to an NFS client, or an ERR_PTR value.
 669 */
 670struct nfs_client *nfs_init_client(struct nfs_client *clp,
 671				   const struct nfs_client_initdata *cl_init)
 672{
 673	int error;
 674
 675	/* the client is already initialised */
 676	if (clp->cl_cons_state == NFS_CS_READY)
 677		return clp;
 678
 679	/*
 680	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
 681	 * - RFC 2623, sec 2.3.2
 682	 */
 683	error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
 684	nfs_mark_client_ready(clp, error == 0 ? NFS_CS_READY : error);
 685	if (error < 0) {
 686		nfs_put_client(clp);
 687		clp = ERR_PTR(error);
 688	}
 689	return clp;
 690}
 691EXPORT_SYMBOL_GPL(nfs_init_client);
 692
 693static void nfs4_server_set_init_caps(struct nfs_server *server)
 694{
 695#if IS_ENABLED(CONFIG_NFS_V4)
 696	/* Set the basic capabilities */
 697	server->caps = server->nfs_client->cl_mvops->init_caps;
 698	if (server->flags & NFS_MOUNT_NORDIRPLUS)
 699		server->caps &= ~NFS_CAP_READDIRPLUS;
 700	if (server->nfs_client->cl_proto == XPRT_TRANSPORT_RDMA)
 701		server->caps &= ~NFS_CAP_READ_PLUS;
 702
 703	/*
 704	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
 705	 * authentication.
 706	 */
 707	if (nfs4_disable_idmapping &&
 708	    server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
 709		server->caps |= NFS_CAP_UIDGID_NOMAP;
 710#endif
 711}
 712
 713void nfs_server_set_init_caps(struct nfs_server *server)
 714{
 715	switch (server->nfs_client->rpc_ops->version) {
 716	case 2:
 717		server->caps = NFS_CAP_HARDLINKS | NFS_CAP_SYMLINKS;
 718		break;
 719	case 3:
 720		server->caps = NFS_CAP_HARDLINKS | NFS_CAP_SYMLINKS;
 721		if (!(server->flags & NFS_MOUNT_NORDIRPLUS))
 722			server->caps |= NFS_CAP_READDIRPLUS;
 723		break;
 724	default:
 725		nfs4_server_set_init_caps(server);
 726		break;
 727	}
 728}
 729EXPORT_SYMBOL_GPL(nfs_server_set_init_caps);
 730
 731/*
 732 * Create a version 2 or 3 client
 733 */
 734static int nfs_init_server(struct nfs_server *server,
 735			   const struct fs_context *fc)
 736{
 737	const struct nfs_fs_context *ctx = nfs_fc2context(fc);
 738	struct rpc_timeout timeparms;
 739	struct nfs_client_initdata cl_init = {
 740		.hostname = ctx->nfs_server.hostname,
 741		.addr = &ctx->nfs_server._address,
 742		.addrlen = ctx->nfs_server.addrlen,
 743		.nfs_mod = ctx->nfs_mod,
 744		.proto = ctx->nfs_server.protocol,
 745		.net = fc->net_ns,
 746		.timeparms = &timeparms,
 747		.cred = server->cred,
 748		.nconnect = ctx->nfs_server.nconnect,
 749		.init_flags = (1UL << NFS_CS_REUSEPORT),
 750		.xprtsec = ctx->xprtsec,
 751	};
 752	struct nfs_client *clp;
 753	int error;
 754
 755	nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
 756				ctx->timeo, ctx->retrans);
 757	if (ctx->flags & NFS_MOUNT_NORESVPORT)
 758		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 759
 760	if (ctx->flags & NFS_MOUNT_NETUNREACH_FATAL)
 761		__set_bit(NFS_CS_NETUNREACH_FATAL, &cl_init.init_flags);
 762
 763	/* Allocate or find a client reference we can use */
 764	clp = nfs_get_client(&cl_init);
 765	if (IS_ERR(clp))
 766		return PTR_ERR(clp);
 767
 768	server->nfs_client = clp;
 769	nfs_sysfs_add_server(server);
 770	nfs_sysfs_link_rpc_client(server, clp->cl_rpcclient, "_state");
 771
 772	/* Initialise the client representation from the mount data */
 773	server->flags = ctx->flags;
 774	server->options = ctx->options;
 775
 776	switch (clp->rpc_ops->version) {
 777	case 2:
 778		server->fattr_valid = NFS_ATTR_FATTR_V2;
 779		break;
 780	case 3:
 781		server->fattr_valid = NFS_ATTR_FATTR_V3;
 782		break;
 783	default:
 784		server->fattr_valid = NFS_ATTR_FATTR_V4;
 785	}
 786
 787	if (ctx->bsize) {
 788		server->bsize = ctx->bsize;
 789		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_BSIZE;
 790	}
 791	if (ctx->rsize) {
 792		server->rsize = nfs_io_size(ctx->rsize, clp->cl_proto);
 793		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_RSIZE;
 794	}
 795	if (ctx->wsize) {
 796		server->wsize = nfs_io_size(ctx->wsize, clp->cl_proto);
 797		server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_WSIZE;
 798	}
 799
 800	server->acregmin = ctx->acregmin * HZ;
 801	server->acregmax = ctx->acregmax * HZ;
 802	server->acdirmin = ctx->acdirmin * HZ;
 803	server->acdirmax = ctx->acdirmax * HZ;
 804
 805	/* Start lockd here, before we might error out */
 806	error = nfs_start_lockd(server);
 807	if (error < 0)
 808		goto error;
 809
 810	server->port = ctx->nfs_server.port;
 811	server->auth_info = ctx->auth_info;
 812
 813	error = nfs_init_server_rpcclient(server, &timeparms,
 814					  ctx->selected_flavor);
 815	if (error < 0)
 816		goto error;
 817
 818	nfs_server_set_init_caps(server);
 819
 820	/* Preserve the values of mount_server-related mount options */
 821	if (ctx->mount_server.addrlen) {
 822		memcpy(&server->mountd_address, &ctx->mount_server.address,
 823			ctx->mount_server.addrlen);
 824		server->mountd_addrlen = ctx->mount_server.addrlen;
 825	}
 826	server->mountd_version = ctx->mount_server.version;
 827	server->mountd_port = ctx->mount_server.port;
 828	server->mountd_protocol = ctx->mount_server.protocol;
 829
 830	server->namelen  = ctx->namlen;
 831	return 0;
 832
 833error:
 834	server->nfs_client = NULL;
 835	nfs_put_client(clp);
 836	return error;
 837}
 838
 839/*
 840 * Load up the server record from information gained in an fsinfo record
 841 */
 842static void nfs_server_set_fsinfo(struct nfs_server *server,
 843				  struct nfs_fsinfo *fsinfo)
 844{
 845	struct nfs_client *clp = server->nfs_client;
 846	unsigned long max_rpc_payload, raw_max_rpc_payload;
 847
 848	/* Work out a lot of parameters */
 849	if (server->rsize == 0)
 850		server->rsize = nfs_io_size(fsinfo->rtpref, clp->cl_proto);
 851	if (server->wsize == 0)
 852		server->wsize = nfs_io_size(fsinfo->wtpref, clp->cl_proto);
 853
 854	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
 855		server->rsize = nfs_io_size(fsinfo->rtmax, clp->cl_proto);
 856	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
 857		server->wsize = nfs_io_size(fsinfo->wtmax, clp->cl_proto);
 858
 859	raw_max_rpc_payload = rpc_max_payload(server->client);
 860	max_rpc_payload = nfs_block_size(raw_max_rpc_payload, NULL);
 861
 862	if (server->rsize > max_rpc_payload)
 863		server->rsize = max_rpc_payload;
 864	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
 865		server->rsize = NFS_MAX_FILE_IO_SIZE;
 866	server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
 867
 868	if (server->wsize > max_rpc_payload)
 869		server->wsize = max_rpc_payload;
 870	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
 871		server->wsize = NFS_MAX_FILE_IO_SIZE;
 872
 873	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
 874
 875	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
 876	if (server->dtsize > NFS_MAX_FILE_IO_SIZE)
 877		server->dtsize = NFS_MAX_FILE_IO_SIZE;
 878	if (server->dtsize > server->rsize)
 879		server->dtsize = server->rsize;
 880
 881	if (server->flags & NFS_MOUNT_NOAC) {
 882		server->acregmin = server->acregmax = 0;
 883		server->acdirmin = server->acdirmax = 0;
 884	}
 885
 886	server->maxfilesize = fsinfo->maxfilesize;
 887
 888	server->change_attr_type = fsinfo->change_attr_type;
 889
 890	server->clone_blksize = fsinfo->clone_blksize;
 891	/* We're airborne Set socket buffersize */
 892	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
 893
 894#ifdef CONFIG_NFS_V4_2
 895	/*
 896	 * Defaults until limited by the session parameters.
 897	 */
 898	server->gxasize = min_t(unsigned int, raw_max_rpc_payload,
 899				XATTR_SIZE_MAX);
 900	server->sxasize = min_t(unsigned int, raw_max_rpc_payload,
 901				XATTR_SIZE_MAX);
 902	server->lxasize = min_t(unsigned int, raw_max_rpc_payload,
 903				nfs42_listxattr_xdrsize(XATTR_LIST_MAX));
 904
 905	if (fsinfo->xattr_support)
 906		server->caps |= NFS_CAP_XATTR;
 907	else
 908		server->caps &= ~NFS_CAP_XATTR;
 909#endif
 910}
 911
 912/*
 913 * Probe filesystem information, including the FSID on v2/v3
 914 */
 915static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
 916{
 917	struct nfs_fsinfo fsinfo;
 918	struct nfs_client *clp = server->nfs_client;
 919	int error;
 920
 921	if (clp->rpc_ops->set_capabilities != NULL) {
 922		error = clp->rpc_ops->set_capabilities(server, mntfh);
 923		if (error < 0)
 924			return error;
 925	}
 926
 927	fsinfo.fattr = fattr;
 928	fsinfo.nlayouttypes = 0;
 929	memset(fsinfo.layouttype, 0, sizeof(fsinfo.layouttype));
 930	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
 931	if (error < 0)
 932		return error;
 933
 934	nfs_server_set_fsinfo(server, &fsinfo);
 935
 936	/* Get some general file system info */
 937	if (server->namelen == 0) {
 938		struct nfs_pathconf pathinfo;
 939
 940		pathinfo.fattr = fattr;
 941		nfs_fattr_init(fattr);
 942
 943		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
 944			server->namelen = pathinfo.max_namelen;
 945	}
 946
 947	if (clp->rpc_ops->discover_trunking != NULL &&
 948			(server->caps & NFS_CAP_FS_LOCATIONS &&
 949			 (server->flags & NFS_MOUNT_TRUNK_DISCOVERY))) {
 950		error = clp->rpc_ops->discover_trunking(server, mntfh);
 951		if (error < 0)
 952			return error;
 953	}
 954
 955	return 0;
 956}
 957
 958/*
 959 * Grab the destination's particulars, including lease expiry time.
 960 *
 961 * Returns zero if probe succeeded and retrieved FSID matches the FSID
 962 * we have cached.
 963 */
 964int nfs_probe_server(struct nfs_server *server, struct nfs_fh *mntfh)
 965{
 966	struct nfs_fattr *fattr;
 967	int error;
 968
 969	fattr = nfs_alloc_fattr();
 970	if (fattr == NULL)
 971		return -ENOMEM;
 972
 973	/* Sanity: the probe won't work if the destination server
 974	 * does not recognize the migrated FH. */
 975	error = nfs_probe_fsinfo(server, mntfh, fattr);
 976
 977	nfs_free_fattr(fattr);
 978	return error;
 979}
 980EXPORT_SYMBOL_GPL(nfs_probe_server);
 981
 982/*
 983 * Copy useful information when duplicating a server record
 984 */
 985void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
 986{
 987	target->flags = source->flags;
 988	target->automount_inherit = source->automount_inherit;
 989	if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_BSIZE)
 990		target->bsize = source->bsize;
 991	if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_RSIZE)
 992		target->rsize = source->rsize;
 993	if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_WSIZE)
 994		target->wsize = source->wsize;
 995	target->acregmin = source->acregmin;
 996	target->acregmax = source->acregmax;
 997	target->acdirmin = source->acdirmin;
 998	target->acdirmax = source->acdirmax;
 999	target->options = source->options;
1000	target->auth_info = source->auth_info;
1001	target->port = source->port;
1002}
1003EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
1004
1005void nfs_server_insert_lists(struct nfs_server *server)
1006{
1007	struct nfs_client *clp = server->nfs_client;
1008	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
1009
1010	spin_lock(&nn->nfs_client_lock);
1011	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
1012	list_add_tail(&server->master_link, &nn->nfs_volume_list);
1013	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
1014	spin_unlock(&nn->nfs_client_lock);
1015
1016}
1017EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
1018
1019void nfs_server_remove_lists(struct nfs_server *server)
1020{
1021	struct nfs_client *clp = server->nfs_client;
1022	struct nfs_net *nn;
1023
1024	if (clp == NULL)
1025		return;
1026	nn = net_generic(clp->cl_net, nfs_net_id);
1027	spin_lock(&nn->nfs_client_lock);
1028	list_del_rcu(&server->client_link);
1029	if (list_empty(&clp->cl_superblocks))
1030		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
1031	list_del(&server->master_link);
1032	spin_unlock(&nn->nfs_client_lock);
1033
1034	synchronize_rcu();
1035}
1036EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
1037
1038static DEFINE_IDA(s_sysfs_ids);
1039
1040/*
1041 * Allocate and initialise a server record
1042 */
1043struct nfs_server *nfs_alloc_server(void)
1044{
1045	struct nfs_server *server;
1046
1047	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
1048	if (!server)
1049		return NULL;
1050
1051	server->s_sysfs_id = ida_alloc(&s_sysfs_ids, GFP_KERNEL);
1052	if (server->s_sysfs_id < 0) {
1053		kfree(server);
1054		return NULL;
1055	}
1056
1057	server->client = server->client_acl = ERR_PTR(-EINVAL);
1058
1059	/* Zero out the NFS state stuff */
1060	INIT_LIST_HEAD(&server->client_link);
1061	INIT_LIST_HEAD(&server->master_link);
1062	INIT_LIST_HEAD(&server->delegations);
1063	INIT_LIST_HEAD(&server->layouts);
1064	INIT_LIST_HEAD(&server->state_owners_lru);
1065	INIT_LIST_HEAD(&server->ss_copies);
1066	INIT_LIST_HEAD(&server->ss_src_copies);
1067
1068	atomic_set(&server->active, 0);
1069	atomic_long_set(&server->nr_active_delegations, 0);
1070
1071	server->io_stats = nfs_alloc_iostats();
1072	if (!server->io_stats) {
1073		kfree(server);
1074		return NULL;
1075	}
1076
1077	server->change_attr_type = NFS4_CHANGE_TYPE_IS_UNDEFINED;
1078
1079	init_waitqueue_head(&server->write_congestion_wait);
1080	atomic_long_set(&server->writeback, 0);
1081
1082	atomic64_set(&server->owner_ctr, 0);
1083
1084	pnfs_init_server(server);
1085	rpc_init_wait_queue(&server->uoc_rpcwaitq, "NFS UOC");
1086
1087	return server;
1088}
1089EXPORT_SYMBOL_GPL(nfs_alloc_server);
1090
1091static void delayed_free(struct rcu_head *p)
1092{
1093	struct nfs_server *server = container_of(p, struct nfs_server, rcu);
1094
1095	nfs_free_iostats(server->io_stats);
1096	kfree(server);
1097}
1098
1099/*
1100 * Free up a server record
1101 */
1102void nfs_free_server(struct nfs_server *server)
1103{
1104	nfs_server_remove_lists(server);
1105
1106	if (server->destroy != NULL)
1107		server->destroy(server);
1108
1109	if (!IS_ERR(server->client_acl))
1110		rpc_shutdown_client(server->client_acl);
1111	if (!IS_ERR(server->client))
1112		rpc_shutdown_client(server->client);
1113
1114	nfs_put_client(server->nfs_client);
1115
1116	if (server->kobj.state_initialized) {
1117		nfs_sysfs_remove_server(server);
1118		kobject_put(&server->kobj);
1119	}
1120	ida_free(&s_sysfs_ids, server->s_sysfs_id);
1121
1122	put_cred(server->cred);
1123	nfs_release_automount_timer();
1124	call_rcu(&server->rcu, delayed_free);
1125}
1126EXPORT_SYMBOL_GPL(nfs_free_server);
1127
1128/*
1129 * Create a version 2 or 3 volume record
1130 * - keyed on server and FSID
1131 */
1132struct nfs_server *nfs_create_server(struct fs_context *fc)
1133{
1134	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1135	struct nfs_server *server;
1136	struct nfs_fattr *fattr;
1137	int error;
1138
1139	server = nfs_alloc_server();
1140	if (!server)
1141		return ERR_PTR(-ENOMEM);
1142
1143	server->cred = get_cred(fc->cred);
1144
1145	error = -ENOMEM;
1146	fattr = nfs_alloc_fattr();
1147	if (fattr == NULL)
1148		goto error;
1149
1150	/* Get a client representation */
1151	error = nfs_init_server(server, fc);
1152	if (error < 0)
1153		goto error;
1154
1155	/* Probe the root fh to retrieve its FSID */
1156	error = nfs_probe_fsinfo(server, ctx->mntfh, fattr);
1157	if (error < 0)
1158		goto error;
1159	if (server->nfs_client->rpc_ops->version == 3) {
1160		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
1161			server->namelen = NFS3_MAXNAMLEN;
1162		if (!(ctx->flags & NFS_MOUNT_NORDIRPLUS))
1163			server->caps |= NFS_CAP_READDIRPLUS;
1164	} else {
1165		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
1166			server->namelen = NFS2_MAXNAMLEN;
1167	}
1168	/* Linux 'subtree_check' borkenness mandates this setting */
1169	server->fh_expire_type = NFS_FH_VOL_RENAME;
1170
1171	if (!(fattr->valid & NFS_ATTR_FATTR)) {
1172		error = ctx->nfs_mod->rpc_ops->getattr(server, ctx->mntfh,
1173						       fattr, NULL);
1174		if (error < 0) {
1175			dprintk("nfs_create_server: getattr error = %d\n", -error);
1176			goto error;
1177		}
1178	}
1179	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1180
1181	dprintk("Server FSID: %llx:%llx\n",
1182		(unsigned long long) server->fsid.major,
1183		(unsigned long long) server->fsid.minor);
1184
1185	nfs_server_insert_lists(server);
1186	server->mount_time = jiffies;
1187	nfs_free_fattr(fattr);
1188	return server;
1189
1190error:
1191	nfs_free_fattr(fattr);
1192	nfs_free_server(server);
1193	return ERR_PTR(error);
1194}
1195EXPORT_SYMBOL_GPL(nfs_create_server);
1196
1197/*
1198 * Clone an NFS2, NFS3 or NFS4 server record
1199 */
1200struct nfs_server *nfs_clone_server(struct nfs_server *source,
1201				    struct nfs_fh *fh,
1202				    struct nfs_fattr *fattr,
1203				    rpc_authflavor_t flavor)
1204{
1205	struct nfs_server *server;
1206	int error;
1207
1208	server = nfs_alloc_server();
1209	if (!server)
1210		return ERR_PTR(-ENOMEM);
1211
1212	server->cred = get_cred(source->cred);
1213
1214	/* Copy data from the source */
1215	server->nfs_client = source->nfs_client;
1216	server->destroy = source->destroy;
1217	refcount_inc(&server->nfs_client->cl_count);
1218	nfs_server_copy_userdata(server, source);
1219
1220	server->fsid = fattr->fsid;
1221
1222	nfs_sysfs_add_server(server);
1223
1224	nfs_sysfs_link_rpc_client(server,
1225		server->nfs_client->cl_rpcclient, "_state");
1226
1227	error = nfs_init_server_rpcclient(server,
1228			source->client->cl_timeout,
1229			flavor);
1230	if (error < 0)
1231		goto out_free_server;
1232
1233	nfs_server_set_init_caps(server);
1234
1235	/* probe the filesystem info for this server filesystem */
1236	error = nfs_probe_server(server, fh);
1237	if (error < 0)
1238		goto out_free_server;
1239
1240	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1241		server->namelen = NFS4_MAXNAMLEN;
1242
1243	error = nfs_start_lockd(server);
1244	if (error < 0)
1245		goto out_free_server;
1246
1247	nfs_server_insert_lists(server);
1248	server->mount_time = jiffies;
1249
1250	return server;
1251
1252out_free_server:
1253	nfs_free_server(server);
1254	return ERR_PTR(error);
1255}
1256EXPORT_SYMBOL_GPL(nfs_clone_server);
1257
1258void nfs_clients_init(struct net *net)
1259{
1260	struct nfs_net *nn = net_generic(net, nfs_net_id);
1261
1262	INIT_LIST_HEAD(&nn->nfs_client_list);
1263	INIT_LIST_HEAD(&nn->nfs_volume_list);
1264#if IS_ENABLED(CONFIG_NFS_V4)
1265	idr_init(&nn->cb_ident_idr);
1266#endif
1267#if IS_ENABLED(CONFIG_NFS_V4_1)
1268	INIT_LIST_HEAD(&nn->nfs4_data_server_cache);
1269	spin_lock_init(&nn->nfs4_data_server_lock);
1270#endif
1271	spin_lock_init(&nn->nfs_client_lock);
1272	nn->boot_time = ktime_get_real();
1273	memset(&nn->rpcstats, 0, sizeof(nn->rpcstats));
1274	nn->rpcstats.program = &nfs_program;
1275
1276	nfs_netns_sysfs_setup(nn, net);
1277}
1278
1279void nfs_clients_exit(struct net *net)
1280{
1281	struct nfs_net *nn = net_generic(net, nfs_net_id);
1282
1283	nfs_netns_sysfs_destroy(nn);
1284	nfs_cleanup_cb_ident_idr(net);
1285	WARN_ON_ONCE(!list_empty(&nn->nfs_client_list));
1286	WARN_ON_ONCE(!list_empty(&nn->nfs_volume_list));
1287#if IS_ENABLED(CONFIG_NFS_V4_1)
1288	WARN_ON_ONCE(!list_empty(&nn->nfs4_data_server_cache));
1289#endif
1290}
1291
1292#ifdef CONFIG_PROC_FS
1293static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1294static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1295static void nfs_server_list_stop(struct seq_file *p, void *v);
1296static int nfs_server_list_show(struct seq_file *m, void *v);
1297
1298static const struct seq_operations nfs_server_list_ops = {
1299	.start	= nfs_server_list_start,
1300	.next	= nfs_server_list_next,
1301	.stop	= nfs_server_list_stop,
1302	.show	= nfs_server_list_show,
1303};
1304
1305static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1306static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1307static void nfs_volume_list_stop(struct seq_file *p, void *v);
1308static int nfs_volume_list_show(struct seq_file *m, void *v);
1309
1310static const struct seq_operations nfs_volume_list_ops = {
1311	.start	= nfs_volume_list_start,
1312	.next	= nfs_volume_list_next,
1313	.stop	= nfs_volume_list_stop,
1314	.show	= nfs_volume_list_show,
1315};
1316
1317/*
1318 * set up the iterator to start reading from the server list and return the first item
1319 */
1320static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1321				__acquires(&nn->nfs_client_lock)
1322{
1323	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1324
1325	/* lock the list against modification */
1326	spin_lock(&nn->nfs_client_lock);
1327	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1328}
1329
1330/*
1331 * move to next server
1332 */
1333static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1334{
1335	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1336
1337	return seq_list_next(v, &nn->nfs_client_list, pos);
1338}
1339
1340/*
1341 * clean up after reading from the transports list
1342 */
1343static void nfs_server_list_stop(struct seq_file *p, void *v)
1344				__releases(&nn->nfs_client_lock)
1345{
1346	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1347
1348	spin_unlock(&nn->nfs_client_lock);
1349}
1350
1351/*
1352 * display a header line followed by a load of call lines
1353 */
1354static int nfs_server_list_show(struct seq_file *m, void *v)
1355{
1356	struct nfs_client *clp;
1357	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1358
1359	/* display header on line 1 */
1360	if (v == &nn->nfs_client_list) {
1361		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1362		return 0;
1363	}
1364
1365	/* display one transport per line on subsequent lines */
1366	clp = list_entry(v, struct nfs_client, cl_share_link);
1367
1368	/* Check if the client is initialized */
1369	if (clp->cl_cons_state != NFS_CS_READY)
1370		return 0;
1371
1372	rcu_read_lock();
1373	seq_printf(m, "v%u %s %s %3d %s\n",
1374		   clp->rpc_ops->version,
1375		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1376		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1377		   refcount_read(&clp->cl_count),
1378		   clp->cl_hostname);
1379	rcu_read_unlock();
1380
1381	return 0;
1382}
1383
1384/*
1385 * set up the iterator to start reading from the volume list and return the first item
1386 */
1387static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1388				__acquires(&nn->nfs_client_lock)
1389{
1390	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1391
1392	/* lock the list against modification */
1393	spin_lock(&nn->nfs_client_lock);
1394	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1395}
1396
1397/*
1398 * move to next volume
1399 */
1400static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1401{
1402	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1403
1404	return seq_list_next(v, &nn->nfs_volume_list, pos);
1405}
1406
1407/*
1408 * clean up after reading from the transports list
1409 */
1410static void nfs_volume_list_stop(struct seq_file *p, void *v)
1411				__releases(&nn->nfs_client_lock)
1412{
1413	struct nfs_net *nn = net_generic(seq_file_net(p), nfs_net_id);
1414
1415	spin_unlock(&nn->nfs_client_lock);
1416}
1417
1418/*
1419 * display a header line followed by a load of call lines
1420 */
1421static int nfs_volume_list_show(struct seq_file *m, void *v)
1422{
1423	struct nfs_server *server;
1424	struct nfs_client *clp;
1425	char dev[13];	// 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1426	char fsid[34];	// 2 * 16 for %llx, 1 for ':', 1 for '\0'
1427	struct nfs_net *nn = net_generic(seq_file_net(m), nfs_net_id);
1428
1429	/* display header on line 1 */
1430	if (v == &nn->nfs_volume_list) {
1431		seq_puts(m, "NV SERVER   PORT DEV          FSID"
1432			    "                              FSC\n");
1433		return 0;
1434	}
1435	/* display one transport per line on subsequent lines */
1436	server = list_entry(v, struct nfs_server, master_link);
1437	clp = server->nfs_client;
1438
1439	snprintf(dev, sizeof(dev), "%u:%u",
1440		 MAJOR(server->s_dev), MINOR(server->s_dev));
1441
1442	snprintf(fsid, sizeof(fsid), "%llx:%llx",
1443		 (unsigned long long) server->fsid.major,
1444		 (unsigned long long) server->fsid.minor);
1445
1446	rcu_read_lock();
1447	seq_printf(m, "v%u %s %s %-12s %-33s %s\n",
1448		   clp->rpc_ops->version,
1449		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1450		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1451		   dev,
1452		   fsid,
1453		   nfs_server_fscache_state(server));
1454	rcu_read_unlock();
1455
1456	return 0;
1457}
1458
1459int nfs_fs_proc_net_init(struct net *net)
1460{
1461	struct nfs_net *nn = net_generic(net, nfs_net_id);
1462	struct proc_dir_entry *p;
1463
1464	nn->proc_nfsfs = proc_net_mkdir(net, "nfsfs", net->proc_net);
1465	if (!nn->proc_nfsfs)
1466		goto error_0;
1467
1468	/* a file of servers with which we're dealing */
1469	p = proc_create_net("servers", S_IFREG|S_IRUGO, nn->proc_nfsfs,
1470			&nfs_server_list_ops, sizeof(struct seq_net_private));
1471	if (!p)
1472		goto error_1;
1473
1474	/* a file of volumes that we have mounted */
1475	p = proc_create_net("volumes", S_IFREG|S_IRUGO, nn->proc_nfsfs,
1476			&nfs_volume_list_ops, sizeof(struct seq_net_private));
1477	if (!p)
1478		goto error_1;
1479	return 0;
1480
1481error_1:
1482	remove_proc_subtree("nfsfs", net->proc_net);
1483error_0:
1484	return -ENOMEM;
1485}
1486
1487void nfs_fs_proc_net_exit(struct net *net)
1488{
1489	remove_proc_subtree("nfsfs", net->proc_net);
1490}
1491
1492/*
1493 * initialise the /proc/fs/nfsfs/ directory
1494 */
1495int __init nfs_fs_proc_init(void)
1496{
1497	if (!proc_mkdir("fs/nfsfs", NULL))
1498		goto error_0;
1499
1500	/* a file of servers with which we're dealing */
1501	if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1502		goto error_1;
1503
1504	/* a file of volumes that we have mounted */
1505	if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1506		goto error_1;
1507
1508	return 0;
1509error_1:
1510	remove_proc_subtree("fs/nfsfs", NULL);
1511error_0:
1512	return -ENOMEM;
1513}
1514
1515/*
1516 * clean up the /proc/fs/nfsfs/ directory
1517 */
1518void nfs_fs_proc_exit(void)
1519{
1520	remove_proc_subtree("fs/nfsfs", NULL);
1521	ida_destroy(&s_sysfs_ids);
1522}
1523
1524#endif /* CONFIG_PROC_FS */