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   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/clnt.h>
  24#include <linux/sunrpc/stats.h>
  25#include <linux/sunrpc/metrics.h>
  26#include <linux/sunrpc/xprtsock.h>
  27#include <linux/sunrpc/xprtrdma.h>
  28#include <linux/nfs_fs.h>
  29#include <linux/nfs_mount.h>
  30#include <linux/nfs4_mount.h>
  31#include <linux/lockd/bind.h>
  32#include <linux/seq_file.h>
  33#include <linux/mount.h>
  34#include <linux/nfs_idmap.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 "netns.h"
  55
  56#define NFSDBG_FACILITY		NFSDBG_CLIENT
  57
  58static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
  59#ifdef CONFIG_NFS_V4
  60
  61/*
  62 * Get a unique NFSv4.0 callback identifier which will be used
  63 * by the V4.0 callback service to lookup the nfs_client struct
  64 */
  65static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
  66{
  67	int ret = 0;
  68	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  69
  70	if (clp->rpc_ops->version != 4 || minorversion != 0)
  71		return ret;
  72retry:
  73	if (!idr_pre_get(&nn->cb_ident_idr, GFP_KERNEL))
  74		return -ENOMEM;
  75	spin_lock(&nn->nfs_client_lock);
  76	ret = idr_get_new(&nn->cb_ident_idr, clp, &clp->cl_cb_ident);
  77	spin_unlock(&nn->nfs_client_lock);
  78	if (ret == -EAGAIN)
  79		goto retry;
  80	return ret;
  81}
  82#endif /* CONFIG_NFS_V4 */
  83
  84/*
  85 * Turn off NFSv4 uid/gid mapping when using AUTH_SYS
  86 */
  87static bool nfs4_disable_idmapping = true;
  88
  89/*
  90 * RPC cruft for NFS
  91 */
  92static const struct rpc_version *nfs_version[5] = {
  93#ifdef CONFIG_NFS_V2
  94	[2]			= &nfs_version2,
  95#endif
  96#ifdef CONFIG_NFS_V3
  97	[3]			= &nfs_version3,
  98#endif
  99#ifdef CONFIG_NFS_V4
 100	[4]			= &nfs_version4,
 101#endif
 102};
 103
 104const struct rpc_program nfs_program = {
 105	.name			= "nfs",
 106	.number			= NFS_PROGRAM,
 107	.nrvers			= ARRAY_SIZE(nfs_version),
 108	.version		= nfs_version,
 109	.stats			= &nfs_rpcstat,
 110	.pipe_dir_name		= NFS_PIPE_DIRNAME,
 111};
 112
 113struct rpc_stat nfs_rpcstat = {
 114	.program		= &nfs_program
 115};
 116
 117
 118#ifdef CONFIG_NFS_V3_ACL
 119static struct rpc_stat		nfsacl_rpcstat = { &nfsacl_program };
 120static const struct rpc_version *nfsacl_version[] = {
 121	[3]			= &nfsacl_version3,
 122};
 123
 124const struct rpc_program nfsacl_program = {
 125	.name			= "nfsacl",
 126	.number			= NFS_ACL_PROGRAM,
 127	.nrvers			= ARRAY_SIZE(nfsacl_version),
 128	.version		= nfsacl_version,
 129	.stats			= &nfsacl_rpcstat,
 130};
 131#endif  /* CONFIG_NFS_V3_ACL */
 132
 133struct nfs_client_initdata {
 134	unsigned long init_flags;
 135	const char *hostname;
 136	const struct sockaddr *addr;
 137	size_t addrlen;
 138	const struct nfs_rpc_ops *rpc_ops;
 139	int proto;
 140	u32 minorversion;
 141	struct net *net;
 142};
 143
 144/*
 145 * Allocate a shared client record
 146 *
 147 * Since these are allocated/deallocated very rarely, we don't
 148 * bother putting them in a slab cache...
 149 */
 150static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 151{
 152	struct nfs_client *clp;
 153	struct rpc_cred *cred;
 154	int err = -ENOMEM;
 155
 156	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
 157		goto error_0;
 158
 159	clp->rpc_ops = cl_init->rpc_ops;
 160
 161	atomic_set(&clp->cl_count, 1);
 162	clp->cl_cons_state = NFS_CS_INITING;
 163
 164	memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
 165	clp->cl_addrlen = cl_init->addrlen;
 166
 167	if (cl_init->hostname) {
 168		err = -ENOMEM;
 169		clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
 170		if (!clp->cl_hostname)
 171			goto error_cleanup;
 172	}
 173
 174	INIT_LIST_HEAD(&clp->cl_superblocks);
 175	clp->cl_rpcclient = ERR_PTR(-EINVAL);
 176
 177	clp->cl_proto = cl_init->proto;
 178	clp->cl_net = get_net(cl_init->net);
 179
 180#ifdef CONFIG_NFS_V4
 181	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
 182	if (err)
 183		goto error_cleanup;
 184
 185	spin_lock_init(&clp->cl_lock);
 186	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
 187	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
 188	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 189	clp->cl_minorversion = cl_init->minorversion;
 190	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 191#endif
 192	cred = rpc_lookup_machine_cred("*");
 193	if (!IS_ERR(cred))
 194		clp->cl_machine_cred = cred;
 195	nfs_fscache_get_client_cookie(clp);
 196
 197	return clp;
 198
 199error_cleanup:
 200	kfree(clp);
 201error_0:
 202	return ERR_PTR(err);
 203}
 204
 205#ifdef CONFIG_NFS_V4
 206#ifdef CONFIG_NFS_V4_1
 207static void nfs4_shutdown_session(struct nfs_client *clp)
 208{
 209	if (nfs4_has_session(clp)) {
 210		nfs4_destroy_session(clp->cl_session);
 211		nfs4_destroy_clientid(clp);
 212	}
 213
 214}
 215#else /* CONFIG_NFS_V4_1 */
 216static void nfs4_shutdown_session(struct nfs_client *clp)
 217{
 218}
 219#endif /* CONFIG_NFS_V4_1 */
 220
 221/*
 222 * Destroy the NFS4 callback service
 223 */
 224static void nfs4_destroy_callback(struct nfs_client *clp)
 225{
 226	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 227		nfs_callback_down(clp->cl_mvops->minor_version);
 228}
 229
 230static void nfs4_shutdown_client(struct nfs_client *clp)
 231{
 232	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 233		nfs4_kill_renewd(clp);
 234	nfs4_shutdown_session(clp);
 235	nfs4_destroy_callback(clp);
 236	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 237		nfs_idmap_delete(clp);
 238
 239	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 240	kfree(clp->cl_serverowner);
 241	kfree(clp->cl_serverscope);
 242	kfree(clp->cl_implid);
 243}
 244
 245/* idr_remove_all is not needed as all id's are removed by nfs_put_client */
 246void nfs_cleanup_cb_ident_idr(struct net *net)
 247{
 248	struct nfs_net *nn = net_generic(net, nfs_net_id);
 249
 250	idr_destroy(&nn->cb_ident_idr);
 251}
 252
 253/* nfs_client_lock held */
 254static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 255{
 256	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 257
 258	if (clp->cl_cb_ident)
 259		idr_remove(&nn->cb_ident_idr, clp->cl_cb_ident);
 260}
 261
 262static void pnfs_init_server(struct nfs_server *server)
 263{
 264	rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
 265}
 266
 267static void nfs4_destroy_server(struct nfs_server *server)
 268{
 269	nfs4_purge_state_owners(server);
 270}
 271
 272#else
 273static void nfs4_shutdown_client(struct nfs_client *clp)
 274{
 275}
 276
 277void nfs_cleanup_cb_ident_idr(struct net *net)
 278{
 279}
 280
 281static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
 282{
 283}
 284
 285static void pnfs_init_server(struct nfs_server *server)
 286{
 287}
 288
 289#endif /* CONFIG_NFS_V4 */
 290
 291/*
 292 * Destroy a shared client record
 293 */
 294static void nfs_free_client(struct nfs_client *clp)
 295{
 296	dprintk("--> nfs_free_client(%u)\n", clp->rpc_ops->version);
 297
 298	nfs4_shutdown_client(clp);
 299
 300	nfs_fscache_release_client_cookie(clp);
 301
 302	/* -EIO all pending I/O */
 303	if (!IS_ERR(clp->cl_rpcclient))
 304		rpc_shutdown_client(clp->cl_rpcclient);
 305
 306	if (clp->cl_machine_cred != NULL)
 307		put_rpccred(clp->cl_machine_cred);
 308
 309	put_net(clp->cl_net);
 310	kfree(clp->cl_hostname);
 311	kfree(clp);
 312
 313	dprintk("<-- nfs_free_client()\n");
 314}
 315
 316/*
 317 * Release a reference to a shared client record
 318 */
 319void nfs_put_client(struct nfs_client *clp)
 320{
 321	struct nfs_net *nn;
 322
 323	if (!clp)
 324		return;
 325
 326	dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
 327	nn = net_generic(clp->cl_net, nfs_net_id);
 328
 329	if (atomic_dec_and_lock(&clp->cl_count, &nn->nfs_client_lock)) {
 330		list_del(&clp->cl_share_link);
 331		nfs_cb_idr_remove_locked(clp);
 332		spin_unlock(&nn->nfs_client_lock);
 333
 334		BUG_ON(!list_empty(&clp->cl_superblocks));
 335
 336		nfs_free_client(clp);
 337	}
 338}
 339EXPORT_SYMBOL_GPL(nfs_put_client);
 340
 341#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 342/*
 343 * Test if two ip6 socket addresses refer to the same socket by
 344 * comparing relevant fields. The padding bytes specifically, are not
 345 * compared. sin6_flowinfo is not compared because it only affects QoS
 346 * and sin6_scope_id is only compared if the address is "link local"
 347 * because "link local" addresses need only be unique to a specific
 348 * link. Conversely, ordinary unicast addresses might have different
 349 * sin6_scope_id.
 350 *
 351 * The caller should ensure both socket addresses are AF_INET6.
 352 */
 353static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
 354				      const struct sockaddr *sa2)
 355{
 356	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
 357	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
 358
 359	if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
 360		return 0;
 361	else if (ipv6_addr_type(&sin1->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 362		return sin1->sin6_scope_id == sin2->sin6_scope_id;
 363
 364	return 1;
 365}
 366#else	/* !defined(CONFIG_IPV6) && !defined(CONFIG_IPV6_MODULE) */
 367static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
 368				      const struct sockaddr *sa2)
 369{
 370	return 0;
 371}
 372#endif
 373
 374/*
 375 * Test if two ip4 socket addresses refer to the same socket, by
 376 * comparing relevant fields. The padding bytes specifically, are
 377 * not compared.
 378 *
 379 * The caller should ensure both socket addresses are AF_INET.
 380 */
 381static int nfs_sockaddr_match_ipaddr4(const struct sockaddr *sa1,
 382				      const struct sockaddr *sa2)
 383{
 384	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
 385	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
 386
 387	return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
 388}
 389
 390static int nfs_sockaddr_cmp_ip6(const struct sockaddr *sa1,
 391				const struct sockaddr *sa2)
 392{
 393	const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
 394	const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
 395
 396	return nfs_sockaddr_match_ipaddr6(sa1, sa2) &&
 397		(sin1->sin6_port == sin2->sin6_port);
 398}
 399
 400static int nfs_sockaddr_cmp_ip4(const struct sockaddr *sa1,
 401				const struct sockaddr *sa2)
 402{
 403	const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
 404	const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
 405
 406	return nfs_sockaddr_match_ipaddr4(sa1, sa2) &&
 407		(sin1->sin_port == sin2->sin_port);
 408}
 409
 410#if defined(CONFIG_NFS_V4_1)
 411/*
 412 * Test if two socket addresses represent the same actual socket,
 413 * by comparing (only) relevant fields, excluding the port number.
 414 */
 415static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
 416				     const struct sockaddr *sa2)
 417{
 418	if (sa1->sa_family != sa2->sa_family)
 419		return 0;
 420
 421	switch (sa1->sa_family) {
 422	case AF_INET:
 423		return nfs_sockaddr_match_ipaddr4(sa1, sa2);
 424	case AF_INET6:
 425		return nfs_sockaddr_match_ipaddr6(sa1, sa2);
 426	}
 427	return 0;
 428}
 429#endif /* CONFIG_NFS_V4_1 */
 430
 431/*
 432 * Test if two socket addresses represent the same actual socket,
 433 * by comparing (only) relevant fields, including the port number.
 434 */
 435static int nfs_sockaddr_cmp(const struct sockaddr *sa1,
 436			    const struct sockaddr *sa2)
 437{
 438	if (sa1->sa_family != sa2->sa_family)
 439		return 0;
 440
 441	switch (sa1->sa_family) {
 442	case AF_INET:
 443		return nfs_sockaddr_cmp_ip4(sa1, sa2);
 444	case AF_INET6:
 445		return nfs_sockaddr_cmp_ip6(sa1, sa2);
 446	}
 447	return 0;
 448}
 449
 450#if defined(CONFIG_NFS_V4_1)
 451/* Common match routine for v4.0 and v4.1 callback services */
 452static bool nfs4_cb_match_client(const struct sockaddr *addr,
 453		struct nfs_client *clp, u32 minorversion)
 454{
 455	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 456
 457	/* Don't match clients that failed to initialise */
 458	if (!(clp->cl_cons_state == NFS_CS_READY ||
 459	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
 460		return false;
 461
 462	smp_rmb();
 463
 464	/* Match the version and minorversion */
 465	if (clp->rpc_ops->version != 4 ||
 466	    clp->cl_minorversion != minorversion)
 467		return false;
 468
 469	/* Match only the IP address, not the port number */
 470	if (!nfs_sockaddr_match_ipaddr(addr, clap))
 471		return false;
 472
 473	return true;
 474}
 475#endif /* CONFIG_NFS_V4_1 */
 476
 477/*
 478 * Find an nfs_client on the list that matches the initialisation data
 479 * that is supplied.
 480 */
 481static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
 482{
 483	struct nfs_client *clp;
 484	const struct sockaddr *sap = data->addr;
 485	struct nfs_net *nn = net_generic(data->net, nfs_net_id);
 486
 487	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 488	        const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 489		/* Don't match clients that failed to initialise properly */
 490		if (clp->cl_cons_state < 0)
 491			continue;
 492
 493		/* Different NFS versions cannot share the same nfs_client */
 494		if (clp->rpc_ops != data->rpc_ops)
 495			continue;
 496
 497		if (clp->cl_proto != data->proto)
 498			continue;
 499		/* Match nfsv4 minorversion */
 500		if (clp->cl_minorversion != data->minorversion)
 501			continue;
 502		/* Match the full socket address */
 503		if (!nfs_sockaddr_cmp(sap, clap))
 504			continue;
 505
 506		atomic_inc(&clp->cl_count);
 507		return clp;
 508	}
 509	return NULL;
 510}
 511
 512static bool nfs_client_init_is_complete(const struct nfs_client *clp)
 513{
 514	return clp->cl_cons_state != NFS_CS_INITING;
 515}
 516
 517int nfs_wait_client_init_complete(const struct nfs_client *clp)
 518{
 519	return wait_event_killable(nfs_client_active_wq,
 520			nfs_client_init_is_complete(clp));
 521}
 522
 523/*
 524 * Found an existing client.  Make sure it's ready before returning.
 525 */
 526static struct nfs_client *
 527nfs_found_client(const struct nfs_client_initdata *cl_init,
 528		 struct nfs_client *clp)
 529{
 530	int error;
 531
 532	error = nfs_wait_client_init_complete(clp);
 533	if (error < 0) {
 534		nfs_put_client(clp);
 535		return ERR_PTR(-ERESTARTSYS);
 536	}
 537
 538	if (clp->cl_cons_state < NFS_CS_READY) {
 539		error = clp->cl_cons_state;
 540		nfs_put_client(clp);
 541		return ERR_PTR(error);
 542	}
 543
 544	smp_rmb();
 545
 546	dprintk("<-- %s found nfs_client %p for %s\n",
 547		__func__, clp, cl_init->hostname ?: "");
 548	return clp;
 549}
 550
 551/*
 552 * Look up a client by IP address and protocol version
 553 * - creates a new record if one doesn't yet exist
 554 */
 555static struct nfs_client *
 556nfs_get_client(const struct nfs_client_initdata *cl_init,
 557	       const struct rpc_timeout *timeparms,
 558	       const char *ip_addr,
 559	       rpc_authflavor_t authflavour)
 560{
 561	struct nfs_client *clp, *new = NULL;
 562	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
 563
 564	dprintk("--> nfs_get_client(%s,v%u)\n",
 565		cl_init->hostname ?: "", cl_init->rpc_ops->version);
 566
 567	/* see if the client already exists */
 568	do {
 569		spin_lock(&nn->nfs_client_lock);
 570
 571		clp = nfs_match_client(cl_init);
 572		if (clp) {
 573			spin_unlock(&nn->nfs_client_lock);
 574			if (new)
 575				nfs_free_client(new);
 576			return nfs_found_client(cl_init, clp);
 577		}
 578		if (new) {
 579			list_add(&new->cl_share_link, &nn->nfs_client_list);
 580			spin_unlock(&nn->nfs_client_lock);
 581			new->cl_flags = cl_init->init_flags;
 582			return cl_init->rpc_ops->init_client(new,
 583						timeparms, ip_addr,
 584						authflavour);
 585		}
 586
 587		spin_unlock(&nn->nfs_client_lock);
 588
 589		new = nfs_alloc_client(cl_init);
 590	} while (!IS_ERR(new));
 591
 592	dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
 593		cl_init->hostname ?: "", PTR_ERR(new));
 594	return new;
 595}
 596
 597/*
 598 * Mark a server as ready or failed
 599 */
 600void nfs_mark_client_ready(struct nfs_client *clp, int state)
 601{
 602	smp_wmb();
 603	clp->cl_cons_state = state;
 604	wake_up_all(&nfs_client_active_wq);
 605}
 606
 607/*
 608 * Initialise the timeout values for a connection
 609 */
 610static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 611				    unsigned int timeo, unsigned int retrans)
 612{
 613	to->to_initval = timeo * HZ / 10;
 614	to->to_retries = retrans;
 615
 616	switch (proto) {
 617	case XPRT_TRANSPORT_TCP:
 618	case XPRT_TRANSPORT_RDMA:
 619		if (to->to_retries == 0)
 620			to->to_retries = NFS_DEF_TCP_RETRANS;
 621		if (to->to_initval == 0)
 622			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
 623		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
 624			to->to_initval = NFS_MAX_TCP_TIMEOUT;
 625		to->to_increment = to->to_initval;
 626		to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
 627		if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
 628			to->to_maxval = NFS_MAX_TCP_TIMEOUT;
 629		if (to->to_maxval < to->to_initval)
 630			to->to_maxval = to->to_initval;
 631		to->to_exponential = 0;
 632		break;
 633	case XPRT_TRANSPORT_UDP:
 634		if (to->to_retries == 0)
 635			to->to_retries = NFS_DEF_UDP_RETRANS;
 636		if (!to->to_initval)
 637			to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
 638		if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
 639			to->to_initval = NFS_MAX_UDP_TIMEOUT;
 640		to->to_maxval = NFS_MAX_UDP_TIMEOUT;
 641		to->to_exponential = 1;
 642		break;
 643	default:
 644		BUG();
 645	}
 646}
 647
 648/*
 649 * Create an RPC client handle
 650 */
 651static int nfs_create_rpc_client(struct nfs_client *clp,
 652				 const struct rpc_timeout *timeparms,
 653				 rpc_authflavor_t flavor)
 654{
 655	struct rpc_clnt		*clnt = NULL;
 656	struct rpc_create_args args = {
 657		.net		= clp->cl_net,
 658		.protocol	= clp->cl_proto,
 659		.address	= (struct sockaddr *)&clp->cl_addr,
 660		.addrsize	= clp->cl_addrlen,
 661		.timeout	= timeparms,
 662		.servername	= clp->cl_hostname,
 663		.program	= &nfs_program,
 664		.version	= clp->rpc_ops->version,
 665		.authflavor	= flavor,
 666	};
 667
 668	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
 669		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
 670	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
 671		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
 672
 673	if (!IS_ERR(clp->cl_rpcclient))
 674		return 0;
 675
 676	clnt = rpc_create(&args);
 677	if (IS_ERR(clnt)) {
 678		dprintk("%s: cannot create RPC client. Error = %ld\n",
 679				__func__, PTR_ERR(clnt));
 680		return PTR_ERR(clnt);
 681	}
 682
 683	clp->cl_rpcclient = clnt;
 684	return 0;
 685}
 686
 687/*
 688 * Version 2 or 3 client destruction
 689 */
 690static void nfs_destroy_server(struct nfs_server *server)
 691{
 692	if (!(server->flags & NFS_MOUNT_LOCAL_FLOCK) ||
 693			!(server->flags & NFS_MOUNT_LOCAL_FCNTL))
 694		nlmclnt_done(server->nlm_host);
 695}
 696
 697/*
 698 * Version 2 or 3 lockd setup
 699 */
 700static int nfs_start_lockd(struct nfs_server *server)
 701{
 702	struct nlm_host *host;
 703	struct nfs_client *clp = server->nfs_client;
 704	struct nlmclnt_initdata nlm_init = {
 705		.hostname	= clp->cl_hostname,
 706		.address	= (struct sockaddr *)&clp->cl_addr,
 707		.addrlen	= clp->cl_addrlen,
 708		.nfs_version	= clp->rpc_ops->version,
 709		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
 710					1 : 0,
 711		.net		= clp->cl_net,
 712	};
 713
 714	if (nlm_init.nfs_version > 3)
 715		return 0;
 716	if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
 717			(server->flags & NFS_MOUNT_LOCAL_FCNTL))
 718		return 0;
 719
 720	switch (clp->cl_proto) {
 721		default:
 722			nlm_init.protocol = IPPROTO_TCP;
 723			break;
 724		case XPRT_TRANSPORT_UDP:
 725			nlm_init.protocol = IPPROTO_UDP;
 726	}
 727
 728	host = nlmclnt_init(&nlm_init);
 729	if (IS_ERR(host))
 730		return PTR_ERR(host);
 731
 732	server->nlm_host = host;
 733	server->destroy = nfs_destroy_server;
 734	return 0;
 735}
 736
 737/*
 738 * Initialise an NFSv3 ACL client connection
 739 */
 740#ifdef CONFIG_NFS_V3_ACL
 741static void nfs_init_server_aclclient(struct nfs_server *server)
 742{
 743	if (server->nfs_client->rpc_ops->version != 3)
 744		goto out_noacl;
 745	if (server->flags & NFS_MOUNT_NOACL)
 746		goto out_noacl;
 747
 748	server->client_acl = rpc_bind_new_program(server->client, &nfsacl_program, 3);
 749	if (IS_ERR(server->client_acl))
 750		goto out_noacl;
 751
 752	/* No errors! Assume that Sun nfsacls are supported */
 753	server->caps |= NFS_CAP_ACLS;
 754	return;
 755
 756out_noacl:
 757	server->caps &= ~NFS_CAP_ACLS;
 758}
 759#else
 760static inline void nfs_init_server_aclclient(struct nfs_server *server)
 761{
 762	server->flags &= ~NFS_MOUNT_NOACL;
 763	server->caps &= ~NFS_CAP_ACLS;
 764}
 765#endif
 766
 767/*
 768 * Create a general RPC client
 769 */
 770static int nfs_init_server_rpcclient(struct nfs_server *server,
 771		const struct rpc_timeout *timeo,
 772		rpc_authflavor_t pseudoflavour)
 773{
 774	struct nfs_client *clp = server->nfs_client;
 775
 776	server->client = rpc_clone_client(clp->cl_rpcclient);
 777	if (IS_ERR(server->client)) {
 778		dprintk("%s: couldn't create rpc_client!\n", __func__);
 779		return PTR_ERR(server->client);
 780	}
 781
 782	memcpy(&server->client->cl_timeout_default,
 783			timeo,
 784			sizeof(server->client->cl_timeout_default));
 785	server->client->cl_timeout = &server->client->cl_timeout_default;
 786
 787	if (pseudoflavour != clp->cl_rpcclient->cl_auth->au_flavor) {
 788		struct rpc_auth *auth;
 789
 790		auth = rpcauth_create(pseudoflavour, server->client);
 791		if (IS_ERR(auth)) {
 792			dprintk("%s: couldn't create credcache!\n", __func__);
 793			return PTR_ERR(auth);
 794		}
 795	}
 796	server->client->cl_softrtry = 0;
 797	if (server->flags & NFS_MOUNT_SOFT)
 798		server->client->cl_softrtry = 1;
 799
 800	return 0;
 801}
 802
 803/**
 804 * nfs_init_client - Initialise an NFS2 or NFS3 client
 805 *
 806 * @clp: nfs_client to initialise
 807 * @timeparms: timeout parameters for underlying RPC transport
 808 * @ip_addr: IP presentation address (not used)
 809 * @authflavor: authentication flavor for underlying RPC transport
 810 *
 811 * Returns pointer to an NFS client, or an ERR_PTR value.
 812 */
 813struct nfs_client *nfs_init_client(struct nfs_client *clp,
 814		    const struct rpc_timeout *timeparms,
 815		    const char *ip_addr, rpc_authflavor_t authflavour)
 816{
 817	int error;
 818
 819	if (clp->cl_cons_state == NFS_CS_READY) {
 820		/* the client is already initialised */
 821		dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
 822		return clp;
 823	}
 824
 825	/*
 826	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
 827	 * - RFC 2623, sec 2.3.2
 828	 */
 829	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
 830	if (error < 0)
 831		goto error;
 832	nfs_mark_client_ready(clp, NFS_CS_READY);
 833	return clp;
 834
 835error:
 836	nfs_mark_client_ready(clp, error);
 837	nfs_put_client(clp);
 838	dprintk("<-- nfs_init_client() = xerror %d\n", error);
 839	return ERR_PTR(error);
 840}
 841
 842/*
 843 * Create a version 2 or 3 client
 844 */
 845static int nfs_init_server(struct nfs_server *server,
 846			   const struct nfs_parsed_mount_data *data)
 847{
 848	struct nfs_client_initdata cl_init = {
 849		.hostname = data->nfs_server.hostname,
 850		.addr = (const struct sockaddr *)&data->nfs_server.address,
 851		.addrlen = data->nfs_server.addrlen,
 852		.rpc_ops = NULL,
 853		.proto = data->nfs_server.protocol,
 854		.net = data->net,
 855	};
 856	struct rpc_timeout timeparms;
 857	struct nfs_client *clp;
 858	int error;
 859
 860	dprintk("--> nfs_init_server()\n");
 861
 862	switch (data->version) {
 863#ifdef CONFIG_NFS_V2
 864	case 2:
 865		cl_init.rpc_ops = &nfs_v2_clientops;
 866		break;
 867#endif
 868#ifdef CONFIG_NFS_V3
 869	case 3:
 870		cl_init.rpc_ops = &nfs_v3_clientops;
 871		break;
 872#endif
 873	default:
 874		return -EPROTONOSUPPORT;
 875	}
 876
 877	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 878			data->timeo, data->retrans);
 879	if (data->flags & NFS_MOUNT_NORESVPORT)
 880		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 881
 882	/* Allocate or find a client reference we can use */
 883	clp = nfs_get_client(&cl_init, &timeparms, NULL, RPC_AUTH_UNIX);
 884	if (IS_ERR(clp)) {
 885		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
 886		return PTR_ERR(clp);
 887	}
 888
 889	server->nfs_client = clp;
 890
 891	/* Initialise the client representation from the mount data */
 892	server->flags = data->flags;
 893	server->options = data->options;
 894	server->caps |= NFS_CAP_HARDLINKS|NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
 895		NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|NFS_CAP_OWNER_GROUP|
 896		NFS_CAP_ATIME|NFS_CAP_CTIME|NFS_CAP_MTIME|NFS_CAP_CHANGE_ATTR;
 897
 898	if (data->rsize)
 899		server->rsize = nfs_block_size(data->rsize, NULL);
 900	if (data->wsize)
 901		server->wsize = nfs_block_size(data->wsize, NULL);
 902
 903	server->acregmin = data->acregmin * HZ;
 904	server->acregmax = data->acregmax * HZ;
 905	server->acdirmin = data->acdirmin * HZ;
 906	server->acdirmax = data->acdirmax * HZ;
 907
 908	/* Start lockd here, before we might error out */
 909	error = nfs_start_lockd(server);
 910	if (error < 0)
 911		goto error;
 912
 913	server->port = data->nfs_server.port;
 914
 915	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
 916	if (error < 0)
 917		goto error;
 918
 919	/* Preserve the values of mount_server-related mount options */
 920	if (data->mount_server.addrlen) {
 921		memcpy(&server->mountd_address, &data->mount_server.address,
 922			data->mount_server.addrlen);
 923		server->mountd_addrlen = data->mount_server.addrlen;
 924	}
 925	server->mountd_version = data->mount_server.version;
 926	server->mountd_port = data->mount_server.port;
 927	server->mountd_protocol = data->mount_server.protocol;
 928
 929	server->namelen  = data->namlen;
 930	/* Create a client RPC handle for the NFSv3 ACL management interface */
 931	nfs_init_server_aclclient(server);
 932	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
 933	return 0;
 934
 935error:
 936	server->nfs_client = NULL;
 937	nfs_put_client(clp);
 938	dprintk("<-- nfs_init_server() = xerror %d\n", error);
 939	return error;
 940}
 941
 942/*
 943 * Load up the server record from information gained in an fsinfo record
 944 */
 945static void nfs_server_set_fsinfo(struct nfs_server *server,
 946				  struct nfs_fh *mntfh,
 947				  struct nfs_fsinfo *fsinfo)
 948{
 949	unsigned long max_rpc_payload;
 950
 951	/* Work out a lot of parameters */
 952	if (server->rsize == 0)
 953		server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
 954	if (server->wsize == 0)
 955		server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
 956
 957	if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
 958		server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
 959	if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
 960		server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
 961
 962	max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
 963	if (server->rsize > max_rpc_payload)
 964		server->rsize = max_rpc_payload;
 965	if (server->rsize > NFS_MAX_FILE_IO_SIZE)
 966		server->rsize = NFS_MAX_FILE_IO_SIZE;
 967	server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 968
 969	server->backing_dev_info.name = "nfs";
 970	server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
 971
 972	if (server->wsize > max_rpc_payload)
 973		server->wsize = max_rpc_payload;
 974	if (server->wsize > NFS_MAX_FILE_IO_SIZE)
 975		server->wsize = NFS_MAX_FILE_IO_SIZE;
 976	server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 977	server->pnfs_blksize = fsinfo->blksize;
 978	set_pnfs_layoutdriver(server, mntfh, fsinfo->layouttype);
 979
 980	server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
 981
 982	server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
 983	if (server->dtsize > PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES)
 984		server->dtsize = PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES;
 985	if (server->dtsize > server->rsize)
 986		server->dtsize = server->rsize;
 987
 988	if (server->flags & NFS_MOUNT_NOAC) {
 989		server->acregmin = server->acregmax = 0;
 990		server->acdirmin = server->acdirmax = 0;
 991	}
 992
 993	server->maxfilesize = fsinfo->maxfilesize;
 994
 995	server->time_delta = fsinfo->time_delta;
 996
 997	/* We're airborne Set socket buffersize */
 998	rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
 999}
1000
1001/*
1002 * Probe filesystem information, including the FSID on v2/v3
1003 */
1004static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
1005{
1006	struct nfs_fsinfo fsinfo;
1007	struct nfs_client *clp = server->nfs_client;
1008	int error;
1009
1010	dprintk("--> nfs_probe_fsinfo()\n");
1011
1012	if (clp->rpc_ops->set_capabilities != NULL) {
1013		error = clp->rpc_ops->set_capabilities(server, mntfh);
1014		if (error < 0)
1015			goto out_error;
1016	}
1017
1018	fsinfo.fattr = fattr;
1019	fsinfo.layouttype = 0;
1020	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
1021	if (error < 0)
1022		goto out_error;
1023
1024	nfs_server_set_fsinfo(server, mntfh, &fsinfo);
1025
1026	/* Get some general file system info */
1027	if (server->namelen == 0) {
1028		struct nfs_pathconf pathinfo;
1029
1030		pathinfo.fattr = fattr;
1031		nfs_fattr_init(fattr);
1032
1033		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
1034			server->namelen = pathinfo.max_namelen;
1035	}
1036
1037	dprintk("<-- nfs_probe_fsinfo() = 0\n");
1038	return 0;
1039
1040out_error:
1041	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
1042	return error;
1043}
1044
1045/*
1046 * Copy useful information when duplicating a server record
1047 */
1048static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
1049{
1050	target->flags = source->flags;
1051	target->rsize = source->rsize;
1052	target->wsize = source->wsize;
1053	target->acregmin = source->acregmin;
1054	target->acregmax = source->acregmax;
1055	target->acdirmin = source->acdirmin;
1056	target->acdirmax = source->acdirmax;
1057	target->caps = source->caps;
1058	target->options = source->options;
1059}
1060
1061static void nfs_server_insert_lists(struct nfs_server *server)
1062{
1063	struct nfs_client *clp = server->nfs_client;
1064	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
1065
1066	spin_lock(&nn->nfs_client_lock);
1067	list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
1068	list_add_tail(&server->master_link, &nn->nfs_volume_list);
1069	clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
1070	spin_unlock(&nn->nfs_client_lock);
1071
1072}
1073
1074static void nfs_server_remove_lists(struct nfs_server *server)
1075{
1076	struct nfs_client *clp = server->nfs_client;
1077	struct nfs_net *nn;
1078
1079	if (clp == NULL)
1080		return;
1081	nn = net_generic(clp->cl_net, nfs_net_id);
1082	spin_lock(&nn->nfs_client_lock);
1083	list_del_rcu(&server->client_link);
1084	if (list_empty(&clp->cl_superblocks))
1085		set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
1086	list_del(&server->master_link);
1087	spin_unlock(&nn->nfs_client_lock);
1088
1089	synchronize_rcu();
1090}
1091
1092/*
1093 * Allocate and initialise a server record
1094 */
1095static struct nfs_server *nfs_alloc_server(void)
1096{
1097	struct nfs_server *server;
1098
1099	server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
1100	if (!server)
1101		return NULL;
1102
1103	server->client = server->client_acl = ERR_PTR(-EINVAL);
1104
1105	/* Zero out the NFS state stuff */
1106	INIT_LIST_HEAD(&server->client_link);
1107	INIT_LIST_HEAD(&server->master_link);
1108	INIT_LIST_HEAD(&server->delegations);
1109	INIT_LIST_HEAD(&server->layouts);
1110	INIT_LIST_HEAD(&server->state_owners_lru);
1111
1112	atomic_set(&server->active, 0);
1113
1114	server->io_stats = nfs_alloc_iostats();
1115	if (!server->io_stats) {
1116		kfree(server);
1117		return NULL;
1118	}
1119
1120	if (bdi_init(&server->backing_dev_info)) {
1121		nfs_free_iostats(server->io_stats);
1122		kfree(server);
1123		return NULL;
1124	}
1125
1126	ida_init(&server->openowner_id);
1127	ida_init(&server->lockowner_id);
1128	pnfs_init_server(server);
1129
1130	return server;
1131}
1132
1133/*
1134 * Free up a server record
1135 */
1136void nfs_free_server(struct nfs_server *server)
1137{
1138	dprintk("--> nfs_free_server()\n");
1139
1140	nfs_server_remove_lists(server);
1141	unset_pnfs_layoutdriver(server);
1142
1143	if (server->destroy != NULL)
1144		server->destroy(server);
1145
1146	if (!IS_ERR(server->client_acl))
1147		rpc_shutdown_client(server->client_acl);
1148	if (!IS_ERR(server->client))
1149		rpc_shutdown_client(server->client);
1150
1151	nfs_put_client(server->nfs_client);
1152
1153	ida_destroy(&server->lockowner_id);
1154	ida_destroy(&server->openowner_id);
1155	nfs_free_iostats(server->io_stats);
1156	bdi_destroy(&server->backing_dev_info);
1157	kfree(server);
1158	nfs_release_automount_timer();
1159	dprintk("<-- nfs_free_server()\n");
1160}
1161
1162/*
1163 * Create a version 2 or 3 volume record
1164 * - keyed on server and FSID
1165 */
1166struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
1167				     struct nfs_fh *mntfh)
1168{
1169	struct nfs_server *server;
1170	struct nfs_fattr *fattr;
1171	int error;
1172
1173	server = nfs_alloc_server();
1174	if (!server)
1175		return ERR_PTR(-ENOMEM);
1176
1177	error = -ENOMEM;
1178	fattr = nfs_alloc_fattr();
1179	if (fattr == NULL)
1180		goto error;
1181
1182	/* Get a client representation */
1183	error = nfs_init_server(server, data);
1184	if (error < 0)
1185		goto error;
1186
1187	BUG_ON(!server->nfs_client);
1188	BUG_ON(!server->nfs_client->rpc_ops);
1189	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1190
1191	/* Probe the root fh to retrieve its FSID */
1192	error = nfs_probe_fsinfo(server, mntfh, fattr);
1193	if (error < 0)
1194		goto error;
1195	if (server->nfs_client->rpc_ops->version == 3) {
1196		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
1197			server->namelen = NFS3_MAXNAMLEN;
1198		if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
1199			server->caps |= NFS_CAP_READDIRPLUS;
1200	} else {
1201		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
1202			server->namelen = NFS2_MAXNAMLEN;
1203	}
1204
1205	if (!(fattr->valid & NFS_ATTR_FATTR)) {
1206		error = server->nfs_client->rpc_ops->getattr(server, mntfh, fattr);
1207		if (error < 0) {
1208			dprintk("nfs_create_server: getattr error = %d\n", -error);
1209			goto error;
1210		}
1211	}
1212	memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1213
1214	dprintk("Server FSID: %llx:%llx\n",
1215		(unsigned long long) server->fsid.major,
1216		(unsigned long long) server->fsid.minor);
1217
1218	nfs_server_insert_lists(server);
1219	server->mount_time = jiffies;
1220	nfs_free_fattr(fattr);
1221	return server;
1222
1223error:
1224	nfs_free_fattr(fattr);
1225	nfs_free_server(server);
1226	return ERR_PTR(error);
1227}
1228
1229#ifdef CONFIG_NFS_V4
1230/*
1231 * NFSv4.0 callback thread helper
1232 *
1233 * Find a client by callback identifier
1234 */
1235struct nfs_client *
1236nfs4_find_client_ident(struct net *net, int cb_ident)
1237{
1238	struct nfs_client *clp;
1239	struct nfs_net *nn = net_generic(net, nfs_net_id);
1240
1241	spin_lock(&nn->nfs_client_lock);
1242	clp = idr_find(&nn->cb_ident_idr, cb_ident);
1243	if (clp)
1244		atomic_inc(&clp->cl_count);
1245	spin_unlock(&nn->nfs_client_lock);
1246	return clp;
1247}
1248
1249#if defined(CONFIG_NFS_V4_1)
1250/*
1251 * NFSv4.1 callback thread helper
1252 * For CB_COMPOUND calls, find a client by IP address, protocol version,
1253 * minorversion, and sessionID
1254 *
1255 * Returns NULL if no such client
1256 */
1257struct nfs_client *
1258nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
1259			   struct nfs4_sessionid *sid)
1260{
1261	struct nfs_client *clp;
1262	struct nfs_net *nn = net_generic(net, nfs_net_id);
1263
1264	spin_lock(&nn->nfs_client_lock);
1265	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
1266		if (nfs4_cb_match_client(addr, clp, 1) == false)
1267			continue;
1268
1269		if (!nfs4_has_session(clp))
1270			continue;
1271
1272		/* Match sessionid*/
1273		if (memcmp(clp->cl_session->sess_id.data,
1274		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
1275			continue;
1276
1277		atomic_inc(&clp->cl_count);
1278		spin_unlock(&nn->nfs_client_lock);
1279		return clp;
1280	}
1281	spin_unlock(&nn->nfs_client_lock);
1282	return NULL;
1283}
1284
1285#else /* CONFIG_NFS_V4_1 */
1286
1287struct nfs_client *
1288nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
1289			   struct nfs4_sessionid *sid)
1290{
1291	return NULL;
1292}
1293#endif /* CONFIG_NFS_V4_1 */
1294
1295/*
1296 * Initialize the NFS4 callback service
1297 */
1298static int nfs4_init_callback(struct nfs_client *clp)
1299{
1300	int error;
1301
1302	if (clp->rpc_ops->version == 4) {
1303		struct rpc_xprt *xprt;
1304
1305		xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
1306
1307		if (nfs4_has_session(clp)) {
1308			error = xprt_setup_backchannel(xprt,
1309						NFS41_BC_MIN_CALLBACKS);
1310			if (error < 0)
1311				return error;
1312		}
1313
1314		error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
1315		if (error < 0) {
1316			dprintk("%s: failed to start callback. Error = %d\n",
1317				__func__, error);
1318			return error;
1319		}
1320		__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
1321	}
1322	return 0;
1323}
1324
1325/*
1326 * Initialize the minor version specific parts of an NFS4 client record
1327 */
1328static int nfs4_init_client_minor_version(struct nfs_client *clp)
1329{
1330#if defined(CONFIG_NFS_V4_1)
1331	if (clp->cl_mvops->minor_version) {
1332		struct nfs4_session *session = NULL;
1333		/*
1334		 * Create the session and mark it expired.
1335		 * When a SEQUENCE operation encounters the expired session
1336		 * it will do session recovery to initialize it.
1337		 */
1338		session = nfs4_alloc_session(clp);
1339		if (!session)
1340			return -ENOMEM;
1341
1342		clp->cl_session = session;
1343		/*
1344		 * The create session reply races with the server back
1345		 * channel probe. Mark the client NFS_CS_SESSION_INITING
1346		 * so that the client back channel can find the
1347		 * nfs_client struct
1348		 */
1349		nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
1350	}
1351#endif /* CONFIG_NFS_V4_1 */
1352
1353	return nfs4_init_callback(clp);
1354}
1355
1356/**
1357 * nfs4_init_client - Initialise an NFS4 client record
1358 *
1359 * @clp: nfs_client to initialise
1360 * @timeparms: timeout parameters for underlying RPC transport
1361 * @ip_addr: callback IP address in presentation format
1362 * @authflavor: authentication flavor for underlying RPC transport
1363 *
1364 * Returns pointer to an NFS client, or an ERR_PTR value.
1365 */
1366struct nfs_client *nfs4_init_client(struct nfs_client *clp,
1367				    const struct rpc_timeout *timeparms,
1368				    const char *ip_addr,
1369				    rpc_authflavor_t authflavour)
1370{
1371	char buf[INET6_ADDRSTRLEN + 1];
1372	int error;
1373
1374	if (clp->cl_cons_state == NFS_CS_READY) {
1375		/* the client is initialised already */
1376		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
1377		return clp;
1378	}
1379
1380	/* Check NFS protocol revision and initialize RPC op vector */
1381	clp->rpc_ops = &nfs_v4_clientops;
1382
1383	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
1384	error = nfs_create_rpc_client(clp, timeparms, authflavour);
1385	if (error < 0)
1386		goto error;
1387
1388	/* If no clientaddr= option was specified, find a usable cb address */
1389	if (ip_addr == NULL) {
1390		struct sockaddr_storage cb_addr;
1391		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
1392
1393		error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
1394		if (error < 0)
1395			goto error;
1396		error = rpc_ntop(sap, buf, sizeof(buf));
1397		if (error < 0)
1398			goto error;
1399		ip_addr = (const char *)buf;
1400	}
1401	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
1402
1403	error = nfs_idmap_new(clp);
1404	if (error < 0) {
1405		dprintk("%s: failed to create idmapper. Error = %d\n",
1406			__func__, error);
1407		goto error;
1408	}
1409	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
1410
1411	error = nfs4_init_client_minor_version(clp);
1412	if (error < 0)
1413		goto error;
1414
1415	if (!nfs4_has_session(clp))
1416		nfs_mark_client_ready(clp, NFS_CS_READY);
1417	return clp;
1418
1419error:
1420	nfs_mark_client_ready(clp, error);
1421	nfs_put_client(clp);
1422	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
1423	return ERR_PTR(error);
1424}
1425
1426/*
1427 * Set up an NFS4 client
1428 */
1429static int nfs4_set_client(struct nfs_server *server,
1430		const char *hostname,
1431		const struct sockaddr *addr,
1432		const size_t addrlen,
1433		const char *ip_addr,
1434		rpc_authflavor_t authflavour,
1435		int proto, const struct rpc_timeout *timeparms,
1436		u32 minorversion, struct net *net)
1437{
1438	struct nfs_client_initdata cl_init = {
1439		.hostname = hostname,
1440		.addr = addr,
1441		.addrlen = addrlen,
1442		.rpc_ops = &nfs_v4_clientops,
1443		.proto = proto,
1444		.minorversion = minorversion,
1445		.net = net,
1446	};
1447	struct nfs_client *clp;
1448	int error;
1449
1450	dprintk("--> nfs4_set_client()\n");
1451
1452	if (server->flags & NFS_MOUNT_NORESVPORT)
1453		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
1454
1455	/* Allocate or find a client reference we can use */
1456	clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
1457	if (IS_ERR(clp)) {
1458		error = PTR_ERR(clp);
1459		goto error;
1460	}
1461
1462	/*
1463	 * Query for the lease time on clientid setup or renewal
1464	 *
1465	 * Note that this will be set on nfs_clients that were created
1466	 * only for the DS role and did not set this bit, but now will
1467	 * serve a dual role.
1468	 */
1469	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
1470
1471	server->nfs_client = clp;
1472	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
1473	return 0;
1474error:
1475	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
1476	return error;
1477}
1478
1479/*
1480 * Set up a pNFS Data Server client.
1481 *
1482 * Return any existing nfs_client that matches server address,port,version
1483 * and minorversion.
1484 *
1485 * For a new nfs_client, use a soft mount (default), a low retrans and a
1486 * low timeout interval so that if a connection is lost, we retry through
1487 * the MDS.
1488 */
1489struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
1490		const struct sockaddr *ds_addr, int ds_addrlen,
1491		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans)
1492{
1493	struct nfs_client_initdata cl_init = {
1494		.addr = ds_addr,
1495		.addrlen = ds_addrlen,
1496		.rpc_ops = &nfs_v4_clientops,
1497		.proto = ds_proto,
1498		.minorversion = mds_clp->cl_minorversion,
1499		.net = mds_clp->cl_net,
1500	};
1501	struct rpc_timeout ds_timeout;
1502	struct nfs_client *clp;
1503
1504	/*
1505	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
1506	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
1507	 * (section 13.1 RFC 5661).
1508	 */
1509	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
1510	clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
1511			     mds_clp->cl_rpcclient->cl_auth->au_flavor);
1512
1513	dprintk("<-- %s %p\n", __func__, clp);
1514	return clp;
1515}
1516EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
1517
1518/*
1519 * Session has been established, and the client marked ready.
1520 * Set the mount rsize and wsize with negotiated fore channel
1521 * attributes which will be bound checked in nfs_server_set_fsinfo.
1522 */
1523static void nfs4_session_set_rwsize(struct nfs_server *server)
1524{
1525#ifdef CONFIG_NFS_V4_1
1526	struct nfs4_session *sess;
1527	u32 server_resp_sz;
1528	u32 server_rqst_sz;
1529
1530	if (!nfs4_has_session(server->nfs_client))
1531		return;
1532	sess = server->nfs_client->cl_session;
1533	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
1534	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
1535
1536	if (server->rsize > server_resp_sz)
1537		server->rsize = server_resp_sz;
1538	if (server->wsize > server_rqst_sz)
1539		server->wsize = server_rqst_sz;
1540#endif /* CONFIG_NFS_V4_1 */
1541}
1542
1543static int nfs4_server_common_setup(struct nfs_server *server,
1544		struct nfs_fh *mntfh)
1545{
1546	struct nfs_fattr *fattr;
1547	int error;
1548
1549	BUG_ON(!server->nfs_client);
1550	BUG_ON(!server->nfs_client->rpc_ops);
1551	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1552
1553	/* data servers support only a subset of NFSv4.1 */
1554	if (is_ds_only_client(server->nfs_client))
1555		return -EPROTONOSUPPORT;
1556
1557	fattr = nfs_alloc_fattr();
1558	if (fattr == NULL)
1559		return -ENOMEM;
1560
1561	/* We must ensure the session is initialised first */
1562	error = nfs4_init_session(server);
1563	if (error < 0)
1564		goto out;
1565
1566	/* Probe the root fh to retrieve its FSID and filehandle */
1567	error = nfs4_get_rootfh(server, mntfh);
1568	if (error < 0)
1569		goto out;
1570
1571	dprintk("Server FSID: %llx:%llx\n",
1572			(unsigned long long) server->fsid.major,
1573			(unsigned long long) server->fsid.minor);
1574	dprintk("Mount FH: %d\n", mntfh->size);
1575
1576	nfs4_session_set_rwsize(server);
1577
1578	error = nfs_probe_fsinfo(server, mntfh, fattr);
1579	if (error < 0)
1580		goto out;
1581
1582	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1583		server->namelen = NFS4_MAXNAMLEN;
1584
1585	nfs_server_insert_lists(server);
1586	server->mount_time = jiffies;
1587	server->destroy = nfs4_destroy_server;
1588out:
1589	nfs_free_fattr(fattr);
1590	return error;
1591}
1592
1593/*
1594 * Create a version 4 volume record
1595 */
1596static int nfs4_init_server(struct nfs_server *server,
1597		const struct nfs_parsed_mount_data *data)
1598{
1599	struct rpc_timeout timeparms;
1600	int error;
1601
1602	dprintk("--> nfs4_init_server()\n");
1603
1604	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1605			data->timeo, data->retrans);
1606
1607	/* Initialise the client representation from the mount data */
1608	server->flags = data->flags;
1609	server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|NFS_CAP_POSIX_LOCK;
1610	if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
1611			server->caps |= NFS_CAP_READDIRPLUS;
1612	server->options = data->options;
1613
1614	/* Get a client record */
1615	error = nfs4_set_client(server,
1616			data->nfs_server.hostname,
1617			(const struct sockaddr *)&data->nfs_server.address,
1618			data->nfs_server.addrlen,
1619			data->client_address,
1620			data->auth_flavors[0],
1621			data->nfs_server.protocol,
1622			&timeparms,
1623			data->minorversion,
1624			data->net);
1625	if (error < 0)
1626		goto error;
1627
1628	/*
1629	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
1630	 * authentication.
1631	 */
1632	if (nfs4_disable_idmapping && data->auth_flavors[0] == RPC_AUTH_UNIX)
1633		server->caps |= NFS_CAP_UIDGID_NOMAP;
1634
1635	if (data->rsize)
1636		server->rsize = nfs_block_size(data->rsize, NULL);
1637	if (data->wsize)
1638		server->wsize = nfs_block_size(data->wsize, NULL);
1639
1640	server->acregmin = data->acregmin * HZ;
1641	server->acregmax = data->acregmax * HZ;
1642	server->acdirmin = data->acdirmin * HZ;
1643	server->acdirmax = data->acdirmax * HZ;
1644
1645	server->port = data->nfs_server.port;
1646
1647	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
1648
1649error:
1650	/* Done */
1651	dprintk("<-- nfs4_init_server() = %d\n", error);
1652	return error;
1653}
1654
1655/*
1656 * Create a version 4 volume record
1657 * - keyed on server and FSID
1658 */
1659struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1660				      struct nfs_fh *mntfh)
1661{
1662	struct nfs_server *server;
1663	int error;
1664
1665	dprintk("--> nfs4_create_server()\n");
1666
1667	server = nfs_alloc_server();
1668	if (!server)
1669		return ERR_PTR(-ENOMEM);
1670
1671	/* set up the general RPC client */
1672	error = nfs4_init_server(server, data);
1673	if (error < 0)
1674		goto error;
1675
1676	error = nfs4_server_common_setup(server, mntfh);
1677	if (error < 0)
1678		goto error;
1679
1680	dprintk("<-- nfs4_create_server() = %p\n", server);
1681	return server;
1682
1683error:
1684	nfs_free_server(server);
1685	dprintk("<-- nfs4_create_server() = error %d\n", error);
1686	return ERR_PTR(error);
1687}
1688
1689/*
1690 * Create an NFS4 referral server record
1691 */
1692struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1693					       struct nfs_fh *mntfh)
1694{
1695	struct nfs_client *parent_client;
1696	struct nfs_server *server, *parent_server;
1697	int error;
1698
1699	dprintk("--> nfs4_create_referral_server()\n");
1700
1701	server = nfs_alloc_server();
1702	if (!server)
1703		return ERR_PTR(-ENOMEM);
1704
1705	parent_server = NFS_SB(data->sb);
1706	parent_client = parent_server->nfs_client;
1707
1708	/* Initialise the client representation from the parent server */
1709	nfs_server_copy_userdata(server, parent_server);
1710	server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR;
1711
1712	/* Get a client representation.
1713	 * Note: NFSv4 always uses TCP, */
1714	error = nfs4_set_client(server, data->hostname,
1715				data->addr,
1716				data->addrlen,
1717				parent_client->cl_ipaddr,
1718				data->authflavor,
1719				rpc_protocol(parent_server->client),
1720				parent_server->client->cl_timeout,
1721				parent_client->cl_mvops->minor_version,
1722				parent_client->cl_net);
1723	if (error < 0)
1724		goto error;
1725
1726	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1727	if (error < 0)
1728		goto error;
1729
1730	error = nfs4_server_common_setup(server, mntfh);
1731	if (error < 0)
1732		goto error;
1733
1734	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1735	return server;
1736
1737error:
1738	nfs_free_server(server);
1739	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1740	return ERR_PTR(error);
1741}
1742
1743#endif /* CONFIG_NFS_V4 */
1744
1745/*
1746 * Clone an NFS2, NFS3 or NFS4 server record
1747 */
1748struct nfs_server *nfs_clone_server(struct nfs_server *source,
1749				    struct nfs_fh *fh,
1750				    struct nfs_fattr *fattr,
1751				    rpc_authflavor_t flavor)
1752{
1753	struct nfs_server *server;
1754	struct nfs_fattr *fattr_fsinfo;
1755	int error;
1756
1757	dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1758		(unsigned long long) fattr->fsid.major,
1759		(unsigned long long) fattr->fsid.minor);
1760
1761	server = nfs_alloc_server();
1762	if (!server)
1763		return ERR_PTR(-ENOMEM);
1764
1765	error = -ENOMEM;
1766	fattr_fsinfo = nfs_alloc_fattr();
1767	if (fattr_fsinfo == NULL)
1768		goto out_free_server;
1769
1770	/* Copy data from the source */
1771	server->nfs_client = source->nfs_client;
1772	server->destroy = source->destroy;
1773	atomic_inc(&server->nfs_client->cl_count);
1774	nfs_server_copy_userdata(server, source);
1775
1776	server->fsid = fattr->fsid;
1777
1778	error = nfs_init_server_rpcclient(server,
1779			source->client->cl_timeout,
1780			flavor);
1781	if (error < 0)
1782		goto out_free_server;
1783	if (!IS_ERR(source->client_acl))
1784		nfs_init_server_aclclient(server);
1785
1786	/* probe the filesystem info for this server filesystem */
1787	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
1788	if (error < 0)
1789		goto out_free_server;
1790
1791	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1792		server->namelen = NFS4_MAXNAMLEN;
1793
1794	dprintk("Cloned FSID: %llx:%llx\n",
1795		(unsigned long long) server->fsid.major,
1796		(unsigned long long) server->fsid.minor);
1797
1798	error = nfs_start_lockd(server);
1799	if (error < 0)
1800		goto out_free_server;
1801
1802	nfs_server_insert_lists(server);
1803	server->mount_time = jiffies;
1804
1805	nfs_free_fattr(fattr_fsinfo);
1806	dprintk("<-- nfs_clone_server() = %p\n", server);
1807	return server;
1808
1809out_free_server:
1810	nfs_free_fattr(fattr_fsinfo);
1811	nfs_free_server(server);
1812	dprintk("<-- nfs_clone_server() = error %d\n", error);
1813	return ERR_PTR(error);
1814}
1815
1816void nfs_clients_init(struct net *net)
1817{
1818	struct nfs_net *nn = net_generic(net, nfs_net_id);
1819
1820	INIT_LIST_HEAD(&nn->nfs_client_list);
1821	INIT_LIST_HEAD(&nn->nfs_volume_list);
1822#ifdef CONFIG_NFS_V4
1823	idr_init(&nn->cb_ident_idr);
1824#endif
1825	spin_lock_init(&nn->nfs_client_lock);
1826	nn->boot_time = CURRENT_TIME;
1827}
1828
1829#ifdef CONFIG_PROC_FS
1830static struct proc_dir_entry *proc_fs_nfs;
1831
1832static int nfs_server_list_open(struct inode *inode, struct file *file);
1833static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1834static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1835static void nfs_server_list_stop(struct seq_file *p, void *v);
1836static int nfs_server_list_show(struct seq_file *m, void *v);
1837
1838static const struct seq_operations nfs_server_list_ops = {
1839	.start	= nfs_server_list_start,
1840	.next	= nfs_server_list_next,
1841	.stop	= nfs_server_list_stop,
1842	.show	= nfs_server_list_show,
1843};
1844
1845static const struct file_operations nfs_server_list_fops = {
1846	.open		= nfs_server_list_open,
1847	.read		= seq_read,
1848	.llseek		= seq_lseek,
1849	.release	= seq_release,
1850	.owner		= THIS_MODULE,
1851};
1852
1853static int nfs_volume_list_open(struct inode *inode, struct file *file);
1854static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1855static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1856static void nfs_volume_list_stop(struct seq_file *p, void *v);
1857static int nfs_volume_list_show(struct seq_file *m, void *v);
1858
1859static const struct seq_operations nfs_volume_list_ops = {
1860	.start	= nfs_volume_list_start,
1861	.next	= nfs_volume_list_next,
1862	.stop	= nfs_volume_list_stop,
1863	.show	= nfs_volume_list_show,
1864};
1865
1866static const struct file_operations nfs_volume_list_fops = {
1867	.open		= nfs_volume_list_open,
1868	.read		= seq_read,
1869	.llseek		= seq_lseek,
1870	.release	= seq_release,
1871	.owner		= THIS_MODULE,
1872};
1873
1874/*
1875 * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1876 * we're dealing
1877 */
1878static int nfs_server_list_open(struct inode *inode, struct file *file)
1879{
1880	struct seq_file *m;
1881	int ret;
1882	struct pid_namespace *pid_ns = file->f_dentry->d_sb->s_fs_info;
1883	struct net *net = pid_ns->child_reaper->nsproxy->net_ns;
1884
1885	ret = seq_open(file, &nfs_server_list_ops);
1886	if (ret < 0)
1887		return ret;
1888
1889	m = file->private_data;
1890	m->private = net;
1891
1892	return 0;
1893}
1894
1895/*
1896 * set up the iterator to start reading from the server list and return the first item
1897 */
1898static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1899{
1900	struct nfs_net *nn = net_generic(m->private, nfs_net_id);
1901
1902	/* lock the list against modification */
1903	spin_lock(&nn->nfs_client_lock);
1904	return seq_list_start_head(&nn->nfs_client_list, *_pos);
1905}
1906
1907/*
1908 * move to next server
1909 */
1910static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1911{
1912	struct nfs_net *nn = net_generic(p->private, nfs_net_id);
1913
1914	return seq_list_next(v, &nn->nfs_client_list, pos);
1915}
1916
1917/*
1918 * clean up after reading from the transports list
1919 */
1920static void nfs_server_list_stop(struct seq_file *p, void *v)
1921{
1922	struct nfs_net *nn = net_generic(p->private, nfs_net_id);
1923
1924	spin_unlock(&nn->nfs_client_lock);
1925}
1926
1927/*
1928 * display a header line followed by a load of call lines
1929 */
1930static int nfs_server_list_show(struct seq_file *m, void *v)
1931{
1932	struct nfs_client *clp;
1933	struct nfs_net *nn = net_generic(m->private, nfs_net_id);
1934
1935	/* display header on line 1 */
1936	if (v == &nn->nfs_client_list) {
1937		seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1938		return 0;
1939	}
1940
1941	/* display one transport per line on subsequent lines */
1942	clp = list_entry(v, struct nfs_client, cl_share_link);
1943
1944	/* Check if the client is initialized */
1945	if (clp->cl_cons_state != NFS_CS_READY)
1946		return 0;
1947
1948	rcu_read_lock();
1949	seq_printf(m, "v%u %s %s %3d %s\n",
1950		   clp->rpc_ops->version,
1951		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1952		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1953		   atomic_read(&clp->cl_count),
1954		   clp->cl_hostname);
1955	rcu_read_unlock();
1956
1957	return 0;
1958}
1959
1960/*
1961 * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1962 */
1963static int nfs_volume_list_open(struct inode *inode, struct file *file)
1964{
1965	struct seq_file *m;
1966	int ret;
1967	struct pid_namespace *pid_ns = file->f_dentry->d_sb->s_fs_info;
1968	struct net *net = pid_ns->child_reaper->nsproxy->net_ns;
1969
1970	ret = seq_open(file, &nfs_volume_list_ops);
1971	if (ret < 0)
1972		return ret;
1973
1974	m = file->private_data;
1975	m->private = net;
1976
1977	return 0;
1978}
1979
1980/*
1981 * set up the iterator to start reading from the volume list and return the first item
1982 */
1983static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1984{
1985	struct nfs_net *nn = net_generic(m->private, nfs_net_id);
1986
1987	/* lock the list against modification */
1988	spin_lock(&nn->nfs_client_lock);
1989	return seq_list_start_head(&nn->nfs_volume_list, *_pos);
1990}
1991
1992/*
1993 * move to next volume
1994 */
1995static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1996{
1997	struct nfs_net *nn = net_generic(p->private, nfs_net_id);
1998
1999	return seq_list_next(v, &nn->nfs_volume_list, pos);
2000}
2001
2002/*
2003 * clean up after reading from the transports list
2004 */
2005static void nfs_volume_list_stop(struct seq_file *p, void *v)
2006{
2007	struct nfs_net *nn = net_generic(p->private, nfs_net_id);
2008
2009	spin_unlock(&nn->nfs_client_lock);
2010}
2011
2012/*
2013 * display a header line followed by a load of call lines
2014 */
2015static int nfs_volume_list_show(struct seq_file *m, void *v)
2016{
2017	struct nfs_server *server;
2018	struct nfs_client *clp;
2019	char dev[8], fsid[17];
2020	struct nfs_net *nn = net_generic(m->private, nfs_net_id);
2021
2022	/* display header on line 1 */
2023	if (v == &nn->nfs_volume_list) {
2024		seq_puts(m, "NV SERVER   PORT DEV     FSID              FSC\n");
2025		return 0;
2026	}
2027	/* display one transport per line on subsequent lines */
2028	server = list_entry(v, struct nfs_server, master_link);
2029	clp = server->nfs_client;
2030
2031	snprintf(dev, 8, "%u:%u",
2032		 MAJOR(server->s_dev), MINOR(server->s_dev));
2033
2034	snprintf(fsid, 17, "%llx:%llx",
2035		 (unsigned long long) server->fsid.major,
2036		 (unsigned long long) server->fsid.minor);
2037
2038	rcu_read_lock();
2039	seq_printf(m, "v%u %s %s %-7s %-17s %s\n",
2040		   clp->rpc_ops->version,
2041		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
2042		   rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
2043		   dev,
2044		   fsid,
2045		   nfs_server_fscache_state(server));
2046	rcu_read_unlock();
2047
2048	return 0;
2049}
2050
2051/*
2052 * initialise the /proc/fs/nfsfs/ directory
2053 */
2054int __init nfs_fs_proc_init(void)
2055{
2056	struct proc_dir_entry *p;
2057
2058	proc_fs_nfs = proc_mkdir("fs/nfsfs", NULL);
2059	if (!proc_fs_nfs)
2060		goto error_0;
2061
2062	/* a file of servers with which we're dealing */
2063	p = proc_create("servers", S_IFREG|S_IRUGO,
2064			proc_fs_nfs, &nfs_server_list_fops);
2065	if (!p)
2066		goto error_1;
2067
2068	/* a file of volumes that we have mounted */
2069	p = proc_create("volumes", S_IFREG|S_IRUGO,
2070			proc_fs_nfs, &nfs_volume_list_fops);
2071	if (!p)
2072		goto error_2;
2073	return 0;
2074
2075error_2:
2076	remove_proc_entry("servers", proc_fs_nfs);
2077error_1:
2078	remove_proc_entry("fs/nfsfs", NULL);
2079error_0:
2080	return -ENOMEM;
2081}
2082
2083/*
2084 * clean up the /proc/fs/nfsfs/ directory
2085 */
2086void nfs_fs_proc_exit(void)
2087{
2088	remove_proc_entry("volumes", proc_fs_nfs);
2089	remove_proc_entry("servers", proc_fs_nfs);
2090	remove_proc_entry("fs/nfsfs", NULL);
2091}
2092
2093#endif /* CONFIG_PROC_FS */
2094
2095module_param(nfs4_disable_idmapping, bool, 0644);
2096MODULE_PARM_DESC(nfs4_disable_idmapping,
2097		"Turn off NFSv4 idmapping when using 'sec=sys'");