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v5.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  linux/net/sunrpc/clnt.c
   4 *
   5 *  This file contains the high-level RPC interface.
   6 *  It is modeled as a finite state machine to support both synchronous
   7 *  and asynchronous requests.
   8 *
   9 *  -	RPC header generation and argument serialization.
  10 *  -	Credential refresh.
  11 *  -	TCP connect handling.
  12 *  -	Retry of operation when it is suspected the operation failed because
  13 *	of uid squashing on the server, or when the credentials were stale
  14 *	and need to be refreshed, or when a packet was damaged in transit.
  15 *	This may be have to be moved to the VFS layer.
  16 *
  17 *  Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
  18 *  Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
  19 */
  20
  21
  22#include <linux/module.h>
  23#include <linux/types.h>
  24#include <linux/kallsyms.h>
  25#include <linux/mm.h>
  26#include <linux/namei.h>
  27#include <linux/mount.h>
  28#include <linux/slab.h>
  29#include <linux/rcupdate.h>
  30#include <linux/utsname.h>
  31#include <linux/workqueue.h>
  32#include <linux/in.h>
  33#include <linux/in6.h>
  34#include <linux/un.h>
  35
  36#include <linux/sunrpc/clnt.h>
  37#include <linux/sunrpc/addr.h>
  38#include <linux/sunrpc/rpc_pipe_fs.h>
  39#include <linux/sunrpc/metrics.h>
  40#include <linux/sunrpc/bc_xprt.h>
  41#include <trace/events/sunrpc.h>
  42
  43#include "sunrpc.h"
 
  44#include "netns.h"
  45
  46#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  47# define RPCDBG_FACILITY	RPCDBG_CALL
  48#endif
  49
  50#define dprint_status(t)					\
  51	dprintk("RPC: %5u %s (status %d)\n", t->tk_pid,		\
  52			__func__, t->tk_status)
  53
  54/*
  55 * All RPC clients are linked into this list
  56 */
  57
  58static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
  59
  60
  61static void	call_start(struct rpc_task *task);
  62static void	call_reserve(struct rpc_task *task);
  63static void	call_reserveresult(struct rpc_task *task);
  64static void	call_allocate(struct rpc_task *task);
  65static void	call_encode(struct rpc_task *task);
  66static void	call_decode(struct rpc_task *task);
  67static void	call_bind(struct rpc_task *task);
  68static void	call_bind_status(struct rpc_task *task);
  69static void	call_transmit(struct rpc_task *task);
  70static void	call_status(struct rpc_task *task);
  71static void	call_transmit_status(struct rpc_task *task);
  72static void	call_refresh(struct rpc_task *task);
  73static void	call_refreshresult(struct rpc_task *task);
  74static void	call_connect(struct rpc_task *task);
  75static void	call_connect_status(struct rpc_task *task);
  76
  77static int	rpc_encode_header(struct rpc_task *task,
  78				  struct xdr_stream *xdr);
  79static int	rpc_decode_header(struct rpc_task *task,
  80				  struct xdr_stream *xdr);
  81static int	rpc_ping(struct rpc_clnt *clnt);
 
  82static void	rpc_check_timeout(struct rpc_task *task);
  83
  84static void rpc_register_client(struct rpc_clnt *clnt)
  85{
  86	struct net *net = rpc_net_ns(clnt);
  87	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
  88
  89	spin_lock(&sn->rpc_client_lock);
  90	list_add(&clnt->cl_clients, &sn->all_clients);
  91	spin_unlock(&sn->rpc_client_lock);
  92}
  93
  94static void rpc_unregister_client(struct rpc_clnt *clnt)
  95{
  96	struct net *net = rpc_net_ns(clnt);
  97	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
  98
  99	spin_lock(&sn->rpc_client_lock);
 100	list_del(&clnt->cl_clients);
 101	spin_unlock(&sn->rpc_client_lock);
 102}
 103
 104static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
 105{
 106	rpc_remove_client_dir(clnt);
 107}
 108
 109static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
 110{
 111	struct net *net = rpc_net_ns(clnt);
 112	struct super_block *pipefs_sb;
 113
 114	pipefs_sb = rpc_get_sb_net(net);
 115	if (pipefs_sb) {
 116		__rpc_clnt_remove_pipedir(clnt);
 
 117		rpc_put_sb_net(net);
 118	}
 119}
 120
 121static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
 122				    struct rpc_clnt *clnt)
 123{
 124	static uint32_t clntid;
 125	const char *dir_name = clnt->cl_program->pipe_dir_name;
 126	char name[15];
 127	struct dentry *dir, *dentry;
 128
 129	dir = rpc_d_lookup_sb(sb, dir_name);
 130	if (dir == NULL) {
 131		pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
 132		return dir;
 133	}
 134	for (;;) {
 135		snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
 136		name[sizeof(name) - 1] = '\0';
 137		dentry = rpc_create_client_dir(dir, name, clnt);
 138		if (!IS_ERR(dentry))
 139			break;
 140		if (dentry == ERR_PTR(-EEXIST))
 141			continue;
 142		printk(KERN_INFO "RPC: Couldn't create pipefs entry"
 143				" %s/%s, error %ld\n",
 144				dir_name, name, PTR_ERR(dentry));
 145		break;
 146	}
 147	dput(dir);
 148	return dentry;
 149}
 150
 151static int
 152rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
 153{
 154	struct dentry *dentry;
 155
 
 
 156	if (clnt->cl_program->pipe_dir_name != NULL) {
 157		dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
 158		if (IS_ERR(dentry))
 159			return PTR_ERR(dentry);
 160	}
 161	return 0;
 162}
 163
 164static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
 165{
 166	if (clnt->cl_program->pipe_dir_name == NULL)
 167		return 1;
 168
 169	switch (event) {
 170	case RPC_PIPEFS_MOUNT:
 171		if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
 172			return 1;
 173		if (atomic_read(&clnt->cl_count) == 0)
 174			return 1;
 175		break;
 176	case RPC_PIPEFS_UMOUNT:
 177		if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
 178			return 1;
 179		break;
 180	}
 181	return 0;
 182}
 183
 184static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
 185				   struct super_block *sb)
 186{
 187	struct dentry *dentry;
 188
 189	switch (event) {
 190	case RPC_PIPEFS_MOUNT:
 191		dentry = rpc_setup_pipedir_sb(sb, clnt);
 192		if (!dentry)
 193			return -ENOENT;
 194		if (IS_ERR(dentry))
 195			return PTR_ERR(dentry);
 196		break;
 197	case RPC_PIPEFS_UMOUNT:
 198		__rpc_clnt_remove_pipedir(clnt);
 199		break;
 200	default:
 201		printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
 202		return -ENOTSUPP;
 203	}
 204	return 0;
 205}
 206
 207static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
 208				struct super_block *sb)
 209{
 210	int error = 0;
 211
 212	for (;; clnt = clnt->cl_parent) {
 213		if (!rpc_clnt_skip_event(clnt, event))
 214			error = __rpc_clnt_handle_event(clnt, event, sb);
 215		if (error || clnt == clnt->cl_parent)
 216			break;
 217	}
 218	return error;
 219}
 220
 221static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
 222{
 223	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 224	struct rpc_clnt *clnt;
 225
 226	spin_lock(&sn->rpc_client_lock);
 227	list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
 228		if (rpc_clnt_skip_event(clnt, event))
 229			continue;
 230		spin_unlock(&sn->rpc_client_lock);
 231		return clnt;
 232	}
 233	spin_unlock(&sn->rpc_client_lock);
 234	return NULL;
 235}
 236
 237static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
 238			    void *ptr)
 239{
 240	struct super_block *sb = ptr;
 241	struct rpc_clnt *clnt;
 242	int error = 0;
 243
 244	while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
 245		error = __rpc_pipefs_event(clnt, event, sb);
 246		if (error)
 247			break;
 248	}
 249	return error;
 250}
 251
 252static struct notifier_block rpc_clients_block = {
 253	.notifier_call	= rpc_pipefs_event,
 254	.priority	= SUNRPC_PIPEFS_RPC_PRIO,
 255};
 256
 257int rpc_clients_notifier_register(void)
 258{
 259	return rpc_pipefs_notifier_register(&rpc_clients_block);
 260}
 261
 262void rpc_clients_notifier_unregister(void)
 263{
 264	return rpc_pipefs_notifier_unregister(&rpc_clients_block);
 265}
 266
 267static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
 268		struct rpc_xprt *xprt,
 269		const struct rpc_timeout *timeout)
 270{
 271	struct rpc_xprt *old;
 272
 273	spin_lock(&clnt->cl_lock);
 274	old = rcu_dereference_protected(clnt->cl_xprt,
 275			lockdep_is_held(&clnt->cl_lock));
 276
 277	if (!xprt_bound(xprt))
 278		clnt->cl_autobind = 1;
 279
 280	clnt->cl_timeout = timeout;
 281	rcu_assign_pointer(clnt->cl_xprt, xprt);
 282	spin_unlock(&clnt->cl_lock);
 283
 284	return old;
 285}
 286
 287static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
 288{
 289	clnt->cl_nodelen = strlcpy(clnt->cl_nodename,
 290			nodename, sizeof(clnt->cl_nodename));
 
 
 
 
 
 
 291}
 292
 293static int rpc_client_register(struct rpc_clnt *clnt,
 294			       rpc_authflavor_t pseudoflavor,
 295			       const char *client_name)
 296{
 297	struct rpc_auth_create_args auth_args = {
 298		.pseudoflavor = pseudoflavor,
 299		.target_name = client_name,
 300	};
 301	struct rpc_auth *auth;
 302	struct net *net = rpc_net_ns(clnt);
 303	struct super_block *pipefs_sb;
 304	int err;
 305
 306	rpc_clnt_debugfs_register(clnt);
 307
 308	pipefs_sb = rpc_get_sb_net(net);
 309	if (pipefs_sb) {
 310		err = rpc_setup_pipedir(pipefs_sb, clnt);
 311		if (err)
 312			goto out;
 313	}
 314
 315	rpc_register_client(clnt);
 316	if (pipefs_sb)
 317		rpc_put_sb_net(net);
 318
 319	auth = rpcauth_create(&auth_args, clnt);
 320	if (IS_ERR(auth)) {
 321		dprintk("RPC:       Couldn't create auth handle (flavor %u)\n",
 322				pseudoflavor);
 323		err = PTR_ERR(auth);
 324		goto err_auth;
 325	}
 326	return 0;
 327err_auth:
 328	pipefs_sb = rpc_get_sb_net(net);
 329	rpc_unregister_client(clnt);
 330	__rpc_clnt_remove_pipedir(clnt);
 331out:
 332	if (pipefs_sb)
 333		rpc_put_sb_net(net);
 
 334	rpc_clnt_debugfs_unregister(clnt);
 335	return err;
 336}
 337
 338static DEFINE_IDA(rpc_clids);
 339
 340void rpc_cleanup_clids(void)
 341{
 342	ida_destroy(&rpc_clids);
 343}
 344
 345static int rpc_alloc_clid(struct rpc_clnt *clnt)
 346{
 347	int clid;
 348
 349	clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
 350	if (clid < 0)
 351		return clid;
 352	clnt->cl_clid = clid;
 353	return 0;
 354}
 355
 356static void rpc_free_clid(struct rpc_clnt *clnt)
 357{
 358	ida_simple_remove(&rpc_clids, clnt->cl_clid);
 359}
 360
 361static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
 362		struct rpc_xprt_switch *xps,
 363		struct rpc_xprt *xprt,
 364		struct rpc_clnt *parent)
 365{
 366	const struct rpc_program *program = args->program;
 367	const struct rpc_version *version;
 368	struct rpc_clnt *clnt = NULL;
 369	const struct rpc_timeout *timeout;
 370	const char *nodename = args->nodename;
 371	int err;
 372
 373	/* sanity check the name before trying to print it */
 374	dprintk("RPC:       creating %s client for %s (xprt %p)\n",
 375			program->name, args->servername, xprt);
 376
 377	err = rpciod_up();
 378	if (err)
 379		goto out_no_rpciod;
 380
 381	err = -EINVAL;
 382	if (args->version >= program->nrvers)
 383		goto out_err;
 384	version = program->version[args->version];
 385	if (version == NULL)
 386		goto out_err;
 387
 388	err = -ENOMEM;
 389	clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
 390	if (!clnt)
 391		goto out_err;
 392	clnt->cl_parent = parent ? : clnt;
 
 393
 394	err = rpc_alloc_clid(clnt);
 395	if (err)
 396		goto out_no_clid;
 397
 398	clnt->cl_cred	  = get_cred(args->cred);
 399	clnt->cl_procinfo = version->procs;
 400	clnt->cl_maxproc  = version->nrprocs;
 401	clnt->cl_prog     = args->prognumber ? : program->number;
 402	clnt->cl_vers     = version->number;
 403	clnt->cl_stats    = program->stats;
 404	clnt->cl_metrics  = rpc_alloc_iostats(clnt);
 405	rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
 406	err = -ENOMEM;
 407	if (clnt->cl_metrics == NULL)
 408		goto out_no_stats;
 409	clnt->cl_program  = program;
 410	INIT_LIST_HEAD(&clnt->cl_tasks);
 411	spin_lock_init(&clnt->cl_lock);
 412
 413	timeout = xprt->timeout;
 414	if (args->timeout != NULL) {
 415		memcpy(&clnt->cl_timeout_default, args->timeout,
 416				sizeof(clnt->cl_timeout_default));
 417		timeout = &clnt->cl_timeout_default;
 418	}
 419
 420	rpc_clnt_set_transport(clnt, xprt, timeout);
 
 421	xprt_iter_init(&clnt->cl_xpi, xps);
 422	xprt_switch_put(xps);
 423
 424	clnt->cl_rtt = &clnt->cl_rtt_default;
 425	rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
 426
 427	atomic_set(&clnt->cl_count, 1);
 428
 429	if (nodename == NULL)
 430		nodename = utsname()->nodename;
 431	/* save the nodename */
 432	rpc_clnt_set_nodename(clnt, nodename);
 433
 
 434	err = rpc_client_register(clnt, args->authflavor, args->client_name);
 435	if (err)
 436		goto out_no_path;
 437	if (parent)
 438		atomic_inc(&parent->cl_count);
 
 
 439	return clnt;
 440
 441out_no_path:
 442	rpc_free_iostats(clnt->cl_metrics);
 443out_no_stats:
 444	put_cred(clnt->cl_cred);
 445	rpc_free_clid(clnt);
 446out_no_clid:
 447	kfree(clnt);
 448out_err:
 449	rpciod_down();
 450out_no_rpciod:
 451	xprt_switch_put(xps);
 452	xprt_put(xprt);
 
 453	return ERR_PTR(err);
 454}
 455
 456static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
 457					struct rpc_xprt *xprt)
 458{
 459	struct rpc_clnt *clnt = NULL;
 460	struct rpc_xprt_switch *xps;
 461
 462	if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
 463		WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
 464		xps = args->bc_xprt->xpt_bc_xps;
 465		xprt_switch_get(xps);
 466	} else {
 467		xps = xprt_switch_alloc(xprt, GFP_KERNEL);
 468		if (xps == NULL) {
 469			xprt_put(xprt);
 470			return ERR_PTR(-ENOMEM);
 471		}
 472		if (xprt->bc_xprt) {
 473			xprt_switch_get(xps);
 474			xprt->bc_xprt->xpt_bc_xps = xps;
 475		}
 476	}
 477	clnt = rpc_new_client(args, xps, xprt, NULL);
 478	if (IS_ERR(clnt))
 479		return clnt;
 480
 481	if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
 482		int err = rpc_ping(clnt);
 483		if (err != 0) {
 484			rpc_shutdown_client(clnt);
 485			return ERR_PTR(err);
 486		}
 
 
 
 
 
 
 487	}
 488
 489	clnt->cl_softrtry = 1;
 490	if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
 491		clnt->cl_softrtry = 0;
 492		if (args->flags & RPC_CLNT_CREATE_SOFTERR)
 493			clnt->cl_softerr = 1;
 494	}
 495
 496	if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
 497		clnt->cl_autobind = 1;
 498	if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
 499		clnt->cl_noretranstimeo = 1;
 500	if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
 501		clnt->cl_discrtry = 1;
 502	if (!(args->flags & RPC_CLNT_CREATE_QUIET))
 503		clnt->cl_chatty = 1;
 504
 505	return clnt;
 506}
 507
 508/**
 509 * rpc_create - create an RPC client and transport with one call
 510 * @args: rpc_clnt create argument structure
 511 *
 512 * Creates and initializes an RPC transport and an RPC client.
 513 *
 514 * It can ping the server in order to determine if it is up, and to see if
 515 * it supports this program and version.  RPC_CLNT_CREATE_NOPING disables
 516 * this behavior so asynchronous tasks can also use rpc_create.
 517 */
 518struct rpc_clnt *rpc_create(struct rpc_create_args *args)
 519{
 520	struct rpc_xprt *xprt;
 521	struct xprt_create xprtargs = {
 522		.net = args->net,
 523		.ident = args->protocol,
 524		.srcaddr = args->saddress,
 525		.dstaddr = args->address,
 526		.addrlen = args->addrsize,
 527		.servername = args->servername,
 528		.bc_xprt = args->bc_xprt,
 
 
 
 529	};
 530	char servername[48];
 531	struct rpc_clnt *clnt;
 532	int i;
 533
 534	if (args->bc_xprt) {
 535		WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
 536		xprt = args->bc_xprt->xpt_bc_xprt;
 537		if (xprt) {
 538			xprt_get(xprt);
 539			return rpc_create_xprt(args, xprt);
 540		}
 541	}
 542
 543	if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
 544		xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
 545	if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
 546		xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
 547	/*
 548	 * If the caller chooses not to specify a hostname, whip
 549	 * up a string representation of the passed-in address.
 550	 */
 551	if (xprtargs.servername == NULL) {
 552		struct sockaddr_un *sun =
 553				(struct sockaddr_un *)args->address;
 554		struct sockaddr_in *sin =
 555				(struct sockaddr_in *)args->address;
 556		struct sockaddr_in6 *sin6 =
 557				(struct sockaddr_in6 *)args->address;
 558
 559		servername[0] = '\0';
 560		switch (args->address->sa_family) {
 561		case AF_LOCAL:
 562			snprintf(servername, sizeof(servername), "%s",
 563				 sun->sun_path);
 
 
 
 
 564			break;
 565		case AF_INET:
 566			snprintf(servername, sizeof(servername), "%pI4",
 567				 &sin->sin_addr.s_addr);
 568			break;
 569		case AF_INET6:
 570			snprintf(servername, sizeof(servername), "%pI6",
 571				 &sin6->sin6_addr);
 572			break;
 573		default:
 574			/* caller wants default server name, but
 575			 * address family isn't recognized. */
 576			return ERR_PTR(-EINVAL);
 577		}
 578		xprtargs.servername = servername;
 579	}
 580
 581	xprt = xprt_create_transport(&xprtargs);
 582	if (IS_ERR(xprt))
 583		return (struct rpc_clnt *)xprt;
 584
 585	/*
 586	 * By default, kernel RPC client connects from a reserved port.
 587	 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
 588	 * but it is always enabled for rpciod, which handles the connect
 589	 * operation.
 590	 */
 591	xprt->resvport = 1;
 592	if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
 593		xprt->resvport = 0;
 
 
 
 594
 595	clnt = rpc_create_xprt(args, xprt);
 596	if (IS_ERR(clnt) || args->nconnect <= 1)
 597		return clnt;
 598
 599	for (i = 0; i < args->nconnect - 1; i++) {
 600		if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
 601			break;
 602	}
 603	return clnt;
 604}
 605EXPORT_SYMBOL_GPL(rpc_create);
 606
 607/*
 608 * This function clones the RPC client structure. It allows us to share the
 609 * same transport while varying parameters such as the authentication
 610 * flavour.
 611 */
 612static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
 613					   struct rpc_clnt *clnt)
 614{
 615	struct rpc_xprt_switch *xps;
 616	struct rpc_xprt *xprt;
 617	struct rpc_clnt *new;
 618	int err;
 619
 620	err = -ENOMEM;
 621	rcu_read_lock();
 622	xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
 623	xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
 624	rcu_read_unlock();
 625	if (xprt == NULL || xps == NULL) {
 626		xprt_put(xprt);
 627		xprt_switch_put(xps);
 628		goto out_err;
 629	}
 630	args->servername = xprt->servername;
 631	args->nodename = clnt->cl_nodename;
 632
 633	new = rpc_new_client(args, xps, xprt, clnt);
 634	if (IS_ERR(new)) {
 635		err = PTR_ERR(new);
 636		goto out_err;
 637	}
 638
 639	/* Turn off autobind on clones */
 640	new->cl_autobind = 0;
 641	new->cl_softrtry = clnt->cl_softrtry;
 642	new->cl_softerr = clnt->cl_softerr;
 643	new->cl_noretranstimeo = clnt->cl_noretranstimeo;
 644	new->cl_discrtry = clnt->cl_discrtry;
 645	new->cl_chatty = clnt->cl_chatty;
 646	new->cl_principal = clnt->cl_principal;
 
 647	return new;
 648
 649out_err:
 650	dprintk("RPC:       %s: returned error %d\n", __func__, err);
 651	return ERR_PTR(err);
 652}
 653
 654/**
 655 * rpc_clone_client - Clone an RPC client structure
 656 *
 657 * @clnt: RPC client whose parameters are copied
 658 *
 659 * Returns a fresh RPC client or an ERR_PTR.
 660 */
 661struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
 662{
 663	struct rpc_create_args args = {
 664		.program	= clnt->cl_program,
 665		.prognumber	= clnt->cl_prog,
 666		.version	= clnt->cl_vers,
 667		.authflavor	= clnt->cl_auth->au_flavor,
 668		.cred		= clnt->cl_cred,
 
 669	};
 670	return __rpc_clone_client(&args, clnt);
 671}
 672EXPORT_SYMBOL_GPL(rpc_clone_client);
 673
 674/**
 675 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
 676 *
 677 * @clnt: RPC client whose parameters are copied
 678 * @flavor: security flavor for new client
 679 *
 680 * Returns a fresh RPC client or an ERR_PTR.
 681 */
 682struct rpc_clnt *
 683rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
 684{
 685	struct rpc_create_args args = {
 686		.program	= clnt->cl_program,
 687		.prognumber	= clnt->cl_prog,
 688		.version	= clnt->cl_vers,
 689		.authflavor	= flavor,
 690		.cred		= clnt->cl_cred,
 
 691	};
 692	return __rpc_clone_client(&args, clnt);
 693}
 694EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
 695
 696/**
 697 * rpc_switch_client_transport: switch the RPC transport on the fly
 698 * @clnt: pointer to a struct rpc_clnt
 699 * @args: pointer to the new transport arguments
 700 * @timeout: pointer to the new timeout parameters
 701 *
 702 * This function allows the caller to switch the RPC transport for the
 703 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
 704 * server, for instance.  It assumes that the caller has ensured that
 705 * there are no active RPC tasks by using some form of locking.
 706 *
 707 * Returns zero if "clnt" is now using the new xprt.  Otherwise a
 708 * negative errno is returned, and "clnt" continues to use the old
 709 * xprt.
 710 */
 711int rpc_switch_client_transport(struct rpc_clnt *clnt,
 712		struct xprt_create *args,
 713		const struct rpc_timeout *timeout)
 714{
 715	const struct rpc_timeout *old_timeo;
 716	rpc_authflavor_t pseudoflavor;
 717	struct rpc_xprt_switch *xps, *oldxps;
 718	struct rpc_xprt *xprt, *old;
 719	struct rpc_clnt *parent;
 720	int err;
 721
 
 722	xprt = xprt_create_transport(args);
 723	if (IS_ERR(xprt)) {
 724		dprintk("RPC:       failed to create new xprt for clnt %p\n",
 725			clnt);
 726		return PTR_ERR(xprt);
 727	}
 728
 729	xps = xprt_switch_alloc(xprt, GFP_KERNEL);
 730	if (xps == NULL) {
 731		xprt_put(xprt);
 732		return -ENOMEM;
 733	}
 734
 735	pseudoflavor = clnt->cl_auth->au_flavor;
 736
 737	old_timeo = clnt->cl_timeout;
 738	old = rpc_clnt_set_transport(clnt, xprt, timeout);
 739	oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
 740
 741	rpc_unregister_client(clnt);
 742	__rpc_clnt_remove_pipedir(clnt);
 
 743	rpc_clnt_debugfs_unregister(clnt);
 744
 745	/*
 746	 * A new transport was created.  "clnt" therefore
 747	 * becomes the root of a new cl_parent tree.  clnt's
 748	 * children, if it has any, still point to the old xprt.
 749	 */
 750	parent = clnt->cl_parent;
 751	clnt->cl_parent = clnt;
 752
 753	/*
 754	 * The old rpc_auth cache cannot be re-used.  GSS
 755	 * contexts in particular are between a single
 756	 * client and server.
 757	 */
 758	err = rpc_client_register(clnt, pseudoflavor, NULL);
 759	if (err)
 760		goto out_revert;
 761
 762	synchronize_rcu();
 763	if (parent != clnt)
 764		rpc_release_client(parent);
 765	xprt_switch_put(oldxps);
 766	xprt_put(old);
 767	dprintk("RPC:       replaced xprt for clnt %p\n", clnt);
 768	return 0;
 769
 770out_revert:
 771	xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
 772	rpc_clnt_set_transport(clnt, old, old_timeo);
 773	clnt->cl_parent = parent;
 774	rpc_client_register(clnt, pseudoflavor, NULL);
 775	xprt_switch_put(xps);
 776	xprt_put(xprt);
 777	dprintk("RPC:       failed to switch xprt for clnt %p\n", clnt);
 778	return err;
 779}
 780EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
 781
 782static
 783int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
 784{
 785	struct rpc_xprt_switch *xps;
 786
 787	rcu_read_lock();
 788	xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
 789	rcu_read_unlock();
 
 
 
 
 
 
 
 
 
 
 
 790	if (xps == NULL)
 791		return -EAGAIN;
 792	xprt_iter_init_listall(xpi, xps);
 793	xprt_switch_put(xps);
 794	return 0;
 795}
 796
 
 
 
 
 
 
 
 
 
 
 
 
 
 797/**
 798 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
 799 * @clnt: pointer to client
 800 * @fn: function to apply
 801 * @data: void pointer to function data
 802 *
 803 * Iterates through the list of RPC transports currently attached to the
 804 * client and applies the function fn(clnt, xprt, data).
 805 *
 806 * On error, the iteration stops, and the function returns the error value.
 807 */
 808int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
 809		int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
 810		void *data)
 811{
 812	struct rpc_xprt_iter xpi;
 813	int ret;
 814
 815	ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
 816	if (ret)
 817		return ret;
 818	for (;;) {
 819		struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
 820
 821		if (!xprt)
 822			break;
 823		ret = fn(clnt, xprt, data);
 824		xprt_put(xprt);
 825		if (ret < 0)
 826			break;
 827	}
 828	xprt_iter_destroy(&xpi);
 829	return ret;
 830}
 831EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
 832
 833/*
 834 * Kill all tasks for the given client.
 835 * XXX: kill their descendants as well?
 836 */
 837void rpc_killall_tasks(struct rpc_clnt *clnt)
 838{
 839	struct rpc_task	*rovr;
 840
 841
 842	if (list_empty(&clnt->cl_tasks))
 843		return;
 844	dprintk("RPC:       killing all tasks for client %p\n", clnt);
 845	/*
 846	 * Spin lock all_tasks to prevent changes...
 847	 */
 
 848	spin_lock(&clnt->cl_lock);
 849	list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
 850		rpc_signal_task(rovr);
 851	spin_unlock(&clnt->cl_lock);
 852}
 853EXPORT_SYMBOL_GPL(rpc_killall_tasks);
 854
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 855/*
 856 * Properly shut down an RPC client, terminating all outstanding
 857 * requests.
 858 */
 859void rpc_shutdown_client(struct rpc_clnt *clnt)
 860{
 861	might_sleep();
 862
 863	dprintk_rcu("RPC:       shutting down %s client for %s\n",
 864			clnt->cl_program->name,
 865			rcu_dereference(clnt->cl_xprt)->servername);
 866
 867	while (!list_empty(&clnt->cl_tasks)) {
 868		rpc_killall_tasks(clnt);
 869		wait_event_timeout(destroy_wait,
 870			list_empty(&clnt->cl_tasks), 1*HZ);
 871	}
 872
 873	rpc_release_client(clnt);
 874}
 875EXPORT_SYMBOL_GPL(rpc_shutdown_client);
 876
 877/*
 878 * Free an RPC client
 879 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 880static struct rpc_clnt *
 881rpc_free_client(struct rpc_clnt *clnt)
 882{
 883	struct rpc_clnt *parent = NULL;
 884
 885	dprintk_rcu("RPC:       destroying %s client for %s\n",
 886			clnt->cl_program->name,
 887			rcu_dereference(clnt->cl_xprt)->servername);
 888	if (clnt->cl_parent != clnt)
 889		parent = clnt->cl_parent;
 890	rpc_clnt_debugfs_unregister(clnt);
 891	rpc_clnt_remove_pipedir(clnt);
 892	rpc_unregister_client(clnt);
 893	rpc_free_iostats(clnt->cl_metrics);
 894	clnt->cl_metrics = NULL;
 895	xprt_put(rcu_dereference_raw(clnt->cl_xprt));
 896	xprt_iter_destroy(&clnt->cl_xpi);
 897	rpciod_down();
 898	put_cred(clnt->cl_cred);
 899	rpc_free_clid(clnt);
 900	kfree(clnt);
 
 901	return parent;
 902}
 903
 904/*
 905 * Free an RPC client
 906 */
 907static struct rpc_clnt *
 908rpc_free_auth(struct rpc_clnt *clnt)
 909{
 910	if (clnt->cl_auth == NULL)
 911		return rpc_free_client(clnt);
 912
 913	/*
 914	 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
 915	 *       release remaining GSS contexts. This mechanism ensures
 916	 *       that it can do so safely.
 917	 */
 918	atomic_inc(&clnt->cl_count);
 919	rpcauth_release(clnt->cl_auth);
 920	clnt->cl_auth = NULL;
 921	if (atomic_dec_and_test(&clnt->cl_count))
 
 922		return rpc_free_client(clnt);
 923	return NULL;
 924}
 925
 926/*
 927 * Release reference to the RPC client
 928 */
 929void
 930rpc_release_client(struct rpc_clnt *clnt)
 931{
 932	dprintk("RPC:       rpc_release_client(%p)\n", clnt);
 933
 934	do {
 935		if (list_empty(&clnt->cl_tasks))
 936			wake_up(&destroy_wait);
 937		if (!atomic_dec_and_test(&clnt->cl_count))
 938			break;
 939		clnt = rpc_free_auth(clnt);
 940	} while (clnt != NULL);
 941}
 942EXPORT_SYMBOL_GPL(rpc_release_client);
 943
 944/**
 945 * rpc_bind_new_program - bind a new RPC program to an existing client
 946 * @old: old rpc_client
 947 * @program: rpc program to set
 948 * @vers: rpc program version
 949 *
 950 * Clones the rpc client and sets up a new RPC program. This is mainly
 951 * of use for enabling different RPC programs to share the same transport.
 952 * The Sun NFSv2/v3 ACL protocol can do this.
 953 */
 954struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
 955				      const struct rpc_program *program,
 956				      u32 vers)
 957{
 958	struct rpc_create_args args = {
 959		.program	= program,
 960		.prognumber	= program->number,
 961		.version	= vers,
 962		.authflavor	= old->cl_auth->au_flavor,
 963		.cred		= old->cl_cred,
 
 
 964	};
 965	struct rpc_clnt *clnt;
 966	int err;
 967
 968	clnt = __rpc_clone_client(&args, old);
 969	if (IS_ERR(clnt))
 970		goto out;
 971	err = rpc_ping(clnt);
 972	if (err != 0) {
 973		rpc_shutdown_client(clnt);
 974		clnt = ERR_PTR(err);
 975	}
 976out:
 977	return clnt;
 978}
 979EXPORT_SYMBOL_GPL(rpc_bind_new_program);
 980
 981struct rpc_xprt *
 982rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
 983{
 984	struct rpc_xprt_switch *xps;
 985
 986	if (!xprt)
 987		return NULL;
 988	rcu_read_lock();
 989	xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
 990	atomic_long_inc(&xps->xps_queuelen);
 991	rcu_read_unlock();
 992	atomic_long_inc(&xprt->queuelen);
 993
 994	return xprt;
 995}
 996
 997static void
 998rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
 999{
1000	struct rpc_xprt_switch *xps;
1001
1002	atomic_long_dec(&xprt->queuelen);
1003	rcu_read_lock();
1004	xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1005	atomic_long_dec(&xps->xps_queuelen);
1006	rcu_read_unlock();
1007
1008	xprt_put(xprt);
1009}
1010
1011void rpc_task_release_transport(struct rpc_task *task)
1012{
1013	struct rpc_xprt *xprt = task->tk_xprt;
1014
1015	if (xprt) {
1016		task->tk_xprt = NULL;
1017		if (task->tk_client)
1018			rpc_task_release_xprt(task->tk_client, xprt);
1019		else
1020			xprt_put(xprt);
1021	}
1022}
1023EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1024
1025void rpc_task_release_client(struct rpc_task *task)
1026{
1027	struct rpc_clnt *clnt = task->tk_client;
1028
1029	rpc_task_release_transport(task);
1030	if (clnt != NULL) {
1031		/* Remove from client task list */
1032		spin_lock(&clnt->cl_lock);
1033		list_del(&task->tk_task);
1034		spin_unlock(&clnt->cl_lock);
1035		task->tk_client = NULL;
1036
1037		rpc_release_client(clnt);
1038	}
1039}
1040
1041static struct rpc_xprt *
1042rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1043{
1044	struct rpc_xprt *xprt;
1045
1046	rcu_read_lock();
1047	xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1048	rcu_read_unlock();
1049	return rpc_task_get_xprt(clnt, xprt);
1050}
1051
1052static struct rpc_xprt *
1053rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1054{
1055	return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1056}
1057
1058static
1059void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1060{
1061	if (task->tk_xprt)
1062		return;
 
 
 
 
 
1063	if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1064		task->tk_xprt = rpc_task_get_first_xprt(clnt);
1065	else
1066		task->tk_xprt = rpc_task_get_next_xprt(clnt);
1067}
1068
1069static
1070void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1071{
1072
1073	if (clnt != NULL) {
1074		rpc_task_set_transport(task, clnt);
1075		task->tk_client = clnt;
1076		atomic_inc(&clnt->cl_count);
1077		if (clnt->cl_softrtry)
1078			task->tk_flags |= RPC_TASK_SOFT;
1079		if (clnt->cl_softerr)
1080			task->tk_flags |= RPC_TASK_TIMEOUT;
1081		if (clnt->cl_noretranstimeo)
1082			task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1083		if (atomic_read(&clnt->cl_swapper))
1084			task->tk_flags |= RPC_TASK_SWAPPER;
1085		/* Add to the client's list of all tasks */
1086		spin_lock(&clnt->cl_lock);
1087		list_add_tail(&task->tk_task, &clnt->cl_tasks);
1088		spin_unlock(&clnt->cl_lock);
1089	}
1090}
1091
1092static void
1093rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1094{
1095	if (msg != NULL) {
1096		task->tk_msg.rpc_proc = msg->rpc_proc;
1097		task->tk_msg.rpc_argp = msg->rpc_argp;
1098		task->tk_msg.rpc_resp = msg->rpc_resp;
1099		if (msg->rpc_cred != NULL)
1100			task->tk_msg.rpc_cred = get_cred(msg->rpc_cred);
 
1101	}
1102}
1103
1104/*
1105 * Default callback for async RPC calls
1106 */
1107static void
1108rpc_default_callback(struct rpc_task *task, void *data)
1109{
1110}
1111
1112static const struct rpc_call_ops rpc_default_ops = {
1113	.rpc_call_done = rpc_default_callback,
1114};
1115
1116/**
1117 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1118 * @task_setup_data: pointer to task initialisation data
1119 */
1120struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1121{
1122	struct rpc_task *task;
1123
1124	task = rpc_new_task(task_setup_data);
 
 
 
 
 
1125
1126	rpc_task_set_client(task, task_setup_data->rpc_client);
1127	rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1128
1129	if (task->tk_action == NULL)
1130		rpc_call_start(task);
1131
1132	atomic_inc(&task->tk_count);
1133	rpc_execute(task);
1134	return task;
1135}
1136EXPORT_SYMBOL_GPL(rpc_run_task);
1137
1138/**
1139 * rpc_call_sync - Perform a synchronous RPC call
1140 * @clnt: pointer to RPC client
1141 * @msg: RPC call parameters
1142 * @flags: RPC call flags
1143 */
1144int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1145{
1146	struct rpc_task	*task;
1147	struct rpc_task_setup task_setup_data = {
1148		.rpc_client = clnt,
1149		.rpc_message = msg,
1150		.callback_ops = &rpc_default_ops,
1151		.flags = flags,
1152	};
1153	int status;
1154
1155	WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1156	if (flags & RPC_TASK_ASYNC) {
1157		rpc_release_calldata(task_setup_data.callback_ops,
1158			task_setup_data.callback_data);
1159		return -EINVAL;
1160	}
1161
1162	task = rpc_run_task(&task_setup_data);
1163	if (IS_ERR(task))
1164		return PTR_ERR(task);
1165	status = task->tk_status;
1166	rpc_put_task(task);
1167	return status;
1168}
1169EXPORT_SYMBOL_GPL(rpc_call_sync);
1170
1171/**
1172 * rpc_call_async - Perform an asynchronous RPC call
1173 * @clnt: pointer to RPC client
1174 * @msg: RPC call parameters
1175 * @flags: RPC call flags
1176 * @tk_ops: RPC call ops
1177 * @data: user call data
1178 */
1179int
1180rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1181	       const struct rpc_call_ops *tk_ops, void *data)
1182{
1183	struct rpc_task	*task;
1184	struct rpc_task_setup task_setup_data = {
1185		.rpc_client = clnt,
1186		.rpc_message = msg,
1187		.callback_ops = tk_ops,
1188		.callback_data = data,
1189		.flags = flags|RPC_TASK_ASYNC,
1190	};
1191
1192	task = rpc_run_task(&task_setup_data);
1193	if (IS_ERR(task))
1194		return PTR_ERR(task);
1195	rpc_put_task(task);
1196	return 0;
1197}
1198EXPORT_SYMBOL_GPL(rpc_call_async);
1199
1200#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1201static void call_bc_encode(struct rpc_task *task);
1202
1203/**
1204 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1205 * rpc_execute against it
1206 * @req: RPC request
 
1207 */
1208struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
 
1209{
1210	struct rpc_task *task;
1211	struct rpc_task_setup task_setup_data = {
1212		.callback_ops = &rpc_default_ops,
1213		.flags = RPC_TASK_SOFTCONN |
1214			RPC_TASK_NO_RETRANS_TIMEOUT,
1215	};
1216
1217	dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1218	/*
1219	 * Create an rpc_task to send the data
1220	 */
1221	task = rpc_new_task(&task_setup_data);
1222	xprt_init_bc_request(req, task);
 
 
 
 
 
1223
1224	task->tk_action = call_bc_encode;
1225	atomic_inc(&task->tk_count);
1226	WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1227	rpc_execute(task);
1228
1229	dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1230	return task;
1231}
1232#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1233
1234/**
1235 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1236 * @req: RPC request to prepare
1237 * @pages: vector of struct page pointers
1238 * @base: offset in first page where receive should start, in bytes
1239 * @len: expected size of the upper layer data payload, in bytes
1240 * @hdrsize: expected size of upper layer reply header, in XDR words
1241 *
1242 */
1243void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1244			     unsigned int base, unsigned int len,
1245			     unsigned int hdrsize)
1246{
1247	/* Subtract one to force an extra word of buffer space for the
1248	 * payload's XDR pad to fall into the rcv_buf's tail iovec.
1249	 */
1250	hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign - 1;
1251
1252	xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1253	trace_rpc_reply_pages(req);
1254}
1255EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1256
1257void
1258rpc_call_start(struct rpc_task *task)
1259{
1260	task->tk_action = call_start;
1261}
1262EXPORT_SYMBOL_GPL(rpc_call_start);
1263
1264/**
1265 * rpc_peeraddr - extract remote peer address from clnt's xprt
1266 * @clnt: RPC client structure
1267 * @buf: target buffer
1268 * @bufsize: length of target buffer
1269 *
1270 * Returns the number of bytes that are actually in the stored address.
1271 */
1272size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1273{
1274	size_t bytes;
1275	struct rpc_xprt *xprt;
1276
1277	rcu_read_lock();
1278	xprt = rcu_dereference(clnt->cl_xprt);
1279
1280	bytes = xprt->addrlen;
1281	if (bytes > bufsize)
1282		bytes = bufsize;
1283	memcpy(buf, &xprt->addr, bytes);
1284	rcu_read_unlock();
1285
1286	return bytes;
1287}
1288EXPORT_SYMBOL_GPL(rpc_peeraddr);
1289
1290/**
1291 * rpc_peeraddr2str - return remote peer address in printable format
1292 * @clnt: RPC client structure
1293 * @format: address format
1294 *
1295 * NB: the lifetime of the memory referenced by the returned pointer is
1296 * the same as the rpc_xprt itself.  As long as the caller uses this
1297 * pointer, it must hold the RCU read lock.
1298 */
1299const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1300			     enum rpc_display_format_t format)
1301{
1302	struct rpc_xprt *xprt;
1303
1304	xprt = rcu_dereference(clnt->cl_xprt);
1305
1306	if (xprt->address_strings[format] != NULL)
1307		return xprt->address_strings[format];
1308	else
1309		return "unprintable";
1310}
1311EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1312
1313static const struct sockaddr_in rpc_inaddr_loopback = {
1314	.sin_family		= AF_INET,
1315	.sin_addr.s_addr	= htonl(INADDR_ANY),
1316};
1317
1318static const struct sockaddr_in6 rpc_in6addr_loopback = {
1319	.sin6_family		= AF_INET6,
1320	.sin6_addr		= IN6ADDR_ANY_INIT,
1321};
1322
1323/*
1324 * Try a getsockname() on a connected datagram socket.  Using a
1325 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1326 * This conserves the ephemeral port number space.
1327 *
1328 * Returns zero and fills in "buf" if successful; otherwise, a
1329 * negative errno is returned.
1330 */
1331static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1332			struct sockaddr *buf)
1333{
1334	struct socket *sock;
1335	int err;
1336
1337	err = __sock_create(net, sap->sa_family,
1338				SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1339	if (err < 0) {
1340		dprintk("RPC:       can't create UDP socket (%d)\n", err);
1341		goto out;
1342	}
1343
1344	switch (sap->sa_family) {
1345	case AF_INET:
1346		err = kernel_bind(sock,
1347				(struct sockaddr *)&rpc_inaddr_loopback,
1348				sizeof(rpc_inaddr_loopback));
1349		break;
1350	case AF_INET6:
1351		err = kernel_bind(sock,
1352				(struct sockaddr *)&rpc_in6addr_loopback,
1353				sizeof(rpc_in6addr_loopback));
1354		break;
1355	default:
1356		err = -EAFNOSUPPORT;
1357		goto out;
1358	}
1359	if (err < 0) {
1360		dprintk("RPC:       can't bind UDP socket (%d)\n", err);
1361		goto out_release;
1362	}
1363
1364	err = kernel_connect(sock, sap, salen, 0);
1365	if (err < 0) {
1366		dprintk("RPC:       can't connect UDP socket (%d)\n", err);
1367		goto out_release;
1368	}
1369
1370	err = kernel_getsockname(sock, buf);
1371	if (err < 0) {
1372		dprintk("RPC:       getsockname failed (%d)\n", err);
1373		goto out_release;
1374	}
1375
1376	err = 0;
1377	if (buf->sa_family == AF_INET6) {
1378		struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1379		sin6->sin6_scope_id = 0;
1380	}
1381	dprintk("RPC:       %s succeeded\n", __func__);
1382
1383out_release:
1384	sock_release(sock);
1385out:
1386	return err;
1387}
1388
1389/*
1390 * Scraping a connected socket failed, so we don't have a useable
1391 * local address.  Fallback: generate an address that will prevent
1392 * the server from calling us back.
1393 *
1394 * Returns zero and fills in "buf" if successful; otherwise, a
1395 * negative errno is returned.
1396 */
1397static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1398{
1399	switch (family) {
1400	case AF_INET:
1401		if (buflen < sizeof(rpc_inaddr_loopback))
1402			return -EINVAL;
1403		memcpy(buf, &rpc_inaddr_loopback,
1404				sizeof(rpc_inaddr_loopback));
1405		break;
1406	case AF_INET6:
1407		if (buflen < sizeof(rpc_in6addr_loopback))
1408			return -EINVAL;
1409		memcpy(buf, &rpc_in6addr_loopback,
1410				sizeof(rpc_in6addr_loopback));
1411		break;
1412	default:
1413		dprintk("RPC:       %s: address family not supported\n",
1414			__func__);
1415		return -EAFNOSUPPORT;
1416	}
1417	dprintk("RPC:       %s: succeeded\n", __func__);
1418	return 0;
1419}
1420
1421/**
1422 * rpc_localaddr - discover local endpoint address for an RPC client
1423 * @clnt: RPC client structure
1424 * @buf: target buffer
1425 * @buflen: size of target buffer, in bytes
1426 *
1427 * Returns zero and fills in "buf" and "buflen" if successful;
1428 * otherwise, a negative errno is returned.
1429 *
1430 * This works even if the underlying transport is not currently connected,
1431 * or if the upper layer never previously provided a source address.
1432 *
1433 * The result of this function call is transient: multiple calls in
1434 * succession may give different results, depending on how local
1435 * networking configuration changes over time.
1436 */
1437int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1438{
1439	struct sockaddr_storage address;
1440	struct sockaddr *sap = (struct sockaddr *)&address;
1441	struct rpc_xprt *xprt;
1442	struct net *net;
1443	size_t salen;
1444	int err;
1445
1446	rcu_read_lock();
1447	xprt = rcu_dereference(clnt->cl_xprt);
1448	salen = xprt->addrlen;
1449	memcpy(sap, &xprt->addr, salen);
1450	net = get_net(xprt->xprt_net);
1451	rcu_read_unlock();
1452
1453	rpc_set_port(sap, 0);
1454	err = rpc_sockname(net, sap, salen, buf);
1455	put_net(net);
1456	if (err != 0)
1457		/* Couldn't discover local address, return ANYADDR */
1458		return rpc_anyaddr(sap->sa_family, buf, buflen);
1459	return 0;
1460}
1461EXPORT_SYMBOL_GPL(rpc_localaddr);
1462
1463void
1464rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1465{
1466	struct rpc_xprt *xprt;
1467
1468	rcu_read_lock();
1469	xprt = rcu_dereference(clnt->cl_xprt);
1470	if (xprt->ops->set_buffer_size)
1471		xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1472	rcu_read_unlock();
1473}
1474EXPORT_SYMBOL_GPL(rpc_setbufsize);
1475
1476/**
1477 * rpc_net_ns - Get the network namespace for this RPC client
1478 * @clnt: RPC client to query
1479 *
1480 */
1481struct net *rpc_net_ns(struct rpc_clnt *clnt)
1482{
1483	struct net *ret;
1484
1485	rcu_read_lock();
1486	ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1487	rcu_read_unlock();
1488	return ret;
1489}
1490EXPORT_SYMBOL_GPL(rpc_net_ns);
1491
1492/**
1493 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1494 * @clnt: RPC client to query
1495 *
1496 * For stream transports, this is one RPC record fragment (see RFC
1497 * 1831), as we don't support multi-record requests yet.  For datagram
1498 * transports, this is the size of an IP packet minus the IP, UDP, and
1499 * RPC header sizes.
1500 */
1501size_t rpc_max_payload(struct rpc_clnt *clnt)
1502{
1503	size_t ret;
1504
1505	rcu_read_lock();
1506	ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1507	rcu_read_unlock();
1508	return ret;
1509}
1510EXPORT_SYMBOL_GPL(rpc_max_payload);
1511
1512/**
1513 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1514 * @clnt: RPC client to query
1515 */
1516size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1517{
1518	struct rpc_xprt *xprt;
1519	size_t ret;
1520
1521	rcu_read_lock();
1522	xprt = rcu_dereference(clnt->cl_xprt);
1523	ret = xprt->ops->bc_maxpayload(xprt);
1524	rcu_read_unlock();
1525	return ret;
1526}
1527EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1528
1529unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1530{
1531	struct rpc_xprt *xprt;
1532	unsigned int ret;
1533
1534	rcu_read_lock();
1535	xprt = rcu_dereference(clnt->cl_xprt);
1536	ret = xprt->ops->bc_num_slots(xprt);
1537	rcu_read_unlock();
1538	return ret;
1539}
1540EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1541
1542/**
1543 * rpc_force_rebind - force transport to check that remote port is unchanged
1544 * @clnt: client to rebind
1545 *
1546 */
1547void rpc_force_rebind(struct rpc_clnt *clnt)
1548{
1549	if (clnt->cl_autobind) {
1550		rcu_read_lock();
1551		xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1552		rcu_read_unlock();
1553	}
1554}
1555EXPORT_SYMBOL_GPL(rpc_force_rebind);
1556
1557static int
1558__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1559{
1560	task->tk_status = 0;
1561	task->tk_rpc_status = 0;
1562	task->tk_action = action;
1563	return 1;
1564}
1565
1566/*
1567 * Restart an (async) RPC call. Usually called from within the
1568 * exit handler.
1569 */
1570int
1571rpc_restart_call(struct rpc_task *task)
1572{
1573	return __rpc_restart_call(task, call_start);
1574}
1575EXPORT_SYMBOL_GPL(rpc_restart_call);
1576
1577/*
1578 * Restart an (async) RPC call from the call_prepare state.
1579 * Usually called from within the exit handler.
1580 */
1581int
1582rpc_restart_call_prepare(struct rpc_task *task)
1583{
1584	if (task->tk_ops->rpc_call_prepare != NULL)
1585		return __rpc_restart_call(task, rpc_prepare_task);
1586	return rpc_restart_call(task);
1587}
1588EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1589
1590const char
1591*rpc_proc_name(const struct rpc_task *task)
1592{
1593	const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1594
1595	if (proc) {
1596		if (proc->p_name)
1597			return proc->p_name;
1598		else
1599			return "NULL";
1600	} else
1601		return "no proc";
1602}
1603
1604static void
1605__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1606{
1607	task->tk_rpc_status = rpc_status;
 
1608	rpc_exit(task, tk_status);
1609}
1610
1611static void
1612rpc_call_rpcerror(struct rpc_task *task, int status)
1613{
1614	__rpc_call_rpcerror(task, status, status);
1615}
1616
1617/*
1618 * 0.  Initial state
1619 *
1620 *     Other FSM states can be visited zero or more times, but
1621 *     this state is visited exactly once for each RPC.
1622 */
1623static void
1624call_start(struct rpc_task *task)
1625{
1626	struct rpc_clnt	*clnt = task->tk_client;
1627	int idx = task->tk_msg.rpc_proc->p_statidx;
1628
1629	trace_rpc_request(task);
1630	dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1631			clnt->cl_program->name, clnt->cl_vers,
1632			rpc_proc_name(task),
1633			(RPC_IS_ASYNC(task) ? "async" : "sync"));
 
1634
1635	/* Increment call count (version might not be valid for ping) */
1636	if (clnt->cl_program->version[clnt->cl_vers])
1637		clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1638	clnt->cl_stats->rpccnt++;
1639	task->tk_action = call_reserve;
1640	rpc_task_set_transport(task, clnt);
1641}
1642
1643/*
1644 * 1.	Reserve an RPC call slot
1645 */
1646static void
1647call_reserve(struct rpc_task *task)
1648{
1649	dprint_status(task);
1650
1651	task->tk_status  = 0;
1652	task->tk_action  = call_reserveresult;
1653	xprt_reserve(task);
1654}
1655
1656static void call_retry_reserve(struct rpc_task *task);
1657
1658/*
1659 * 1b.	Grok the result of xprt_reserve()
1660 */
1661static void
1662call_reserveresult(struct rpc_task *task)
1663{
1664	int status = task->tk_status;
1665
1666	dprint_status(task);
1667
1668	/*
1669	 * After a call to xprt_reserve(), we must have either
1670	 * a request slot or else an error status.
1671	 */
1672	task->tk_status = 0;
1673	if (status >= 0) {
1674		if (task->tk_rqstp) {
1675			task->tk_action = call_refresh;
1676			return;
1677		}
1678
1679		printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1680				__func__, status);
1681		rpc_call_rpcerror(task, -EIO);
1682		return;
1683	}
1684
1685	/*
1686	 * Even though there was an error, we may have acquired
1687	 * a request slot somehow.  Make sure not to leak it.
1688	 */
1689	if (task->tk_rqstp) {
1690		printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1691				__func__, status);
1692		xprt_release(task);
1693	}
1694
1695	switch (status) {
1696	case -ENOMEM:
1697		rpc_delay(task, HZ >> 2);
1698		/* fall through */
1699	case -EAGAIN:	/* woken up; retry */
1700		task->tk_action = call_retry_reserve;
1701		return;
1702	case -EIO:	/* probably a shutdown */
1703		break;
1704	default:
1705		printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1706				__func__, status);
1707		break;
1708	}
1709	rpc_call_rpcerror(task, status);
1710}
1711
1712/*
1713 * 1c.	Retry reserving an RPC call slot
1714 */
1715static void
1716call_retry_reserve(struct rpc_task *task)
1717{
1718	dprint_status(task);
1719
1720	task->tk_status  = 0;
1721	task->tk_action  = call_reserveresult;
1722	xprt_retry_reserve(task);
1723}
1724
1725/*
1726 * 2.	Bind and/or refresh the credentials
1727 */
1728static void
1729call_refresh(struct rpc_task *task)
1730{
1731	dprint_status(task);
1732
1733	task->tk_action = call_refreshresult;
1734	task->tk_status = 0;
1735	task->tk_client->cl_stats->rpcauthrefresh++;
1736	rpcauth_refreshcred(task);
1737}
1738
1739/*
1740 * 2a.	Process the results of a credential refresh
1741 */
1742static void
1743call_refreshresult(struct rpc_task *task)
1744{
1745	int status = task->tk_status;
1746
1747	dprint_status(task);
1748
1749	task->tk_status = 0;
1750	task->tk_action = call_refresh;
1751	switch (status) {
1752	case 0:
1753		if (rpcauth_uptodatecred(task)) {
1754			task->tk_action = call_allocate;
1755			return;
1756		}
1757		/* Use rate-limiting and a max number of retries if refresh
1758		 * had status 0 but failed to update the cred.
1759		 */
1760		/* fall through */
1761	case -ETIMEDOUT:
1762		rpc_delay(task, 3*HZ);
1763		/* fall through */
1764	case -EAGAIN:
1765		status = -EACCES;
1766		/* fall through */
1767	case -EKEYEXPIRED:
1768		if (!task->tk_cred_retry)
1769			break;
1770		task->tk_cred_retry--;
1771		dprintk("RPC: %5u %s: retry refresh creds\n",
1772				task->tk_pid, __func__);
 
 
1773		return;
1774	}
1775	dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1776				task->tk_pid, __func__, status);
1777	rpc_call_rpcerror(task, status);
1778}
1779
1780/*
1781 * 2b.	Allocate the buffer. For details, see sched.c:rpc_malloc.
1782 *	(Note: buffer memory is freed in xprt_release).
1783 */
1784static void
1785call_allocate(struct rpc_task *task)
1786{
1787	const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1788	struct rpc_rqst *req = task->tk_rqstp;
1789	struct rpc_xprt *xprt = req->rq_xprt;
1790	const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1791	int status;
1792
1793	dprint_status(task);
1794
1795	task->tk_status = 0;
1796	task->tk_action = call_encode;
1797
1798	if (req->rq_buffer)
1799		return;
1800
1801	if (proc->p_proc != 0) {
1802		BUG_ON(proc->p_arglen == 0);
1803		if (proc->p_decode != NULL)
1804			BUG_ON(proc->p_replen == 0);
1805	}
1806
1807	/*
1808	 * Calculate the size (in quads) of the RPC call
1809	 * and reply headers, and convert both values
1810	 * to byte sizes.
1811	 */
1812	req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1813			   proc->p_arglen;
1814	req->rq_callsize <<= 2;
1815	/*
1816	 * Note: the reply buffer must at minimum allocate enough space
1817	 * for the 'struct accepted_reply' from RFC5531.
1818	 */
1819	req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1820			max_t(size_t, proc->p_replen, 2);
1821	req->rq_rcvsize <<= 2;
1822
1823	status = xprt->ops->buf_alloc(task);
1824	xprt_inject_disconnect(xprt);
1825	if (status == 0)
1826		return;
1827	if (status != -ENOMEM) {
1828		rpc_call_rpcerror(task, status);
1829		return;
1830	}
1831
1832	dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1833
1834	if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1835		task->tk_action = call_allocate;
1836		rpc_delay(task, HZ>>4);
1837		return;
1838	}
1839
1840	rpc_call_rpcerror(task, -ERESTARTSYS);
1841}
1842
1843static int
1844rpc_task_need_encode(struct rpc_task *task)
1845{
1846	return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1847		(!(task->tk_flags & RPC_TASK_SENT) ||
1848		 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1849		 xprt_request_need_retransmit(task));
1850}
1851
1852static void
1853rpc_xdr_encode(struct rpc_task *task)
1854{
1855	struct rpc_rqst	*req = task->tk_rqstp;
1856	struct xdr_stream xdr;
1857
1858	xdr_buf_init(&req->rq_snd_buf,
1859		     req->rq_buffer,
1860		     req->rq_callsize);
1861	xdr_buf_init(&req->rq_rcv_buf,
1862		     req->rq_rbuffer,
1863		     req->rq_rcvsize);
1864
1865	req->rq_reply_bytes_recvd = 0;
1866	req->rq_snd_buf.head[0].iov_len = 0;
1867	xdr_init_encode(&xdr, &req->rq_snd_buf,
1868			req->rq_snd_buf.head[0].iov_base, req);
1869	xdr_free_bvec(&req->rq_snd_buf);
1870	if (rpc_encode_header(task, &xdr))
1871		return;
1872
1873	task->tk_status = rpcauth_wrap_req(task, &xdr);
1874}
1875
1876/*
1877 * 3.	Encode arguments of an RPC call
1878 */
1879static void
1880call_encode(struct rpc_task *task)
1881{
1882	if (!rpc_task_need_encode(task))
1883		goto out;
1884	dprint_status(task);
1885	/* Dequeue task from the receive queue while we're encoding */
1886	xprt_request_dequeue_xprt(task);
1887	/* Encode here so that rpcsec_gss can use correct sequence number. */
1888	rpc_xdr_encode(task);
 
 
 
1889	/* Did the encode result in an error condition? */
1890	if (task->tk_status != 0) {
1891		/* Was the error nonfatal? */
1892		switch (task->tk_status) {
1893		case -EAGAIN:
1894		case -ENOMEM:
1895			rpc_delay(task, HZ >> 4);
1896			break;
1897		case -EKEYEXPIRED:
1898			if (!task->tk_cred_retry) {
1899				rpc_exit(task, task->tk_status);
1900			} else {
1901				task->tk_action = call_refresh;
1902				task->tk_cred_retry--;
1903				dprintk("RPC: %5u %s: retry refresh creds\n",
1904					task->tk_pid, __func__);
1905			}
1906			break;
1907		default:
1908			rpc_call_rpcerror(task, task->tk_status);
1909		}
1910		return;
1911	}
1912
1913	/* Add task to reply queue before transmission to avoid races */
1914	if (rpc_reply_expected(task))
1915		xprt_request_enqueue_receive(task);
1916	xprt_request_enqueue_transmit(task);
1917out:
1918	task->tk_action = call_transmit;
1919	/* Check that the connection is OK */
1920	if (!xprt_bound(task->tk_xprt))
1921		task->tk_action = call_bind;
1922	else if (!xprt_connected(task->tk_xprt))
1923		task->tk_action = call_connect;
1924}
1925
1926/*
1927 * Helpers to check if the task was already transmitted, and
1928 * to take action when that is the case.
1929 */
1930static bool
1931rpc_task_transmitted(struct rpc_task *task)
1932{
1933	return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
1934}
1935
1936static void
1937rpc_task_handle_transmitted(struct rpc_task *task)
1938{
1939	xprt_end_transmit(task);
1940	task->tk_action = call_transmit_status;
1941}
1942
1943/*
1944 * 4.	Get the server port number if not yet set
1945 */
1946static void
1947call_bind(struct rpc_task *task)
1948{
1949	struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1950
1951	if (rpc_task_transmitted(task)) {
1952		rpc_task_handle_transmitted(task);
1953		return;
1954	}
1955
1956	if (xprt_bound(xprt)) {
1957		task->tk_action = call_connect;
1958		return;
1959	}
1960
1961	dprint_status(task);
1962
1963	task->tk_action = call_bind_status;
1964	if (!xprt_prepare_transmit(task))
1965		return;
1966
1967	xprt->ops->rpcbind(task);
1968}
1969
1970/*
1971 * 4a.	Sort out bind result
1972 */
1973static void
1974call_bind_status(struct rpc_task *task)
1975{
1976	struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1977	int status = -EIO;
1978
1979	if (rpc_task_transmitted(task)) {
1980		rpc_task_handle_transmitted(task);
1981		return;
1982	}
1983
1984	dprint_status(task);
1985	trace_rpc_bind_status(task);
1986	if (task->tk_status >= 0)
1987		goto out_next;
1988	if (xprt_bound(xprt)) {
1989		task->tk_status = 0;
1990		goto out_next;
1991	}
1992
1993	switch (task->tk_status) {
1994	case -ENOMEM:
1995		dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1996		rpc_delay(task, HZ >> 2);
1997		goto retry_timeout;
1998	case -EACCES:
1999		dprintk("RPC: %5u remote rpcbind: RPC program/version "
2000				"unavailable\n", task->tk_pid);
2001		/* fail immediately if this is an RPC ping */
2002		if (task->tk_msg.rpc_proc->p_proc == 0) {
2003			status = -EOPNOTSUPP;
2004			break;
2005		}
2006		if (task->tk_rebind_retry == 0)
2007			break;
2008		task->tk_rebind_retry--;
2009		rpc_delay(task, 3*HZ);
2010		goto retry_timeout;
2011	case -ENOBUFS:
2012		rpc_delay(task, HZ >> 2);
2013		goto retry_timeout;
2014	case -EAGAIN:
2015		goto retry_timeout;
2016	case -ETIMEDOUT:
2017		dprintk("RPC: %5u rpcbind request timed out\n",
2018				task->tk_pid);
2019		goto retry_timeout;
2020	case -EPFNOSUPPORT:
2021		/* server doesn't support any rpcbind version we know of */
2022		dprintk("RPC: %5u unrecognized remote rpcbind service\n",
2023				task->tk_pid);
2024		break;
2025	case -EPROTONOSUPPORT:
2026		dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
2027				task->tk_pid);
2028		goto retry_timeout;
2029	case -ECONNREFUSED:		/* connection problems */
2030	case -ECONNRESET:
2031	case -ECONNABORTED:
2032	case -ENOTCONN:
2033	case -EHOSTDOWN:
2034	case -ENETDOWN:
2035	case -EHOSTUNREACH:
2036	case -ENETUNREACH:
2037	case -EPIPE:
2038		dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
2039				task->tk_pid, task->tk_status);
2040		if (!RPC_IS_SOFTCONN(task)) {
2041			rpc_delay(task, 5*HZ);
2042			goto retry_timeout;
2043		}
2044		status = task->tk_status;
2045		break;
2046	default:
2047		dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
2048				task->tk_pid, -task->tk_status);
2049	}
2050
2051	rpc_call_rpcerror(task, status);
2052	return;
2053out_next:
2054	task->tk_action = call_connect;
2055	return;
2056retry_timeout:
2057	task->tk_status = 0;
2058	task->tk_action = call_bind;
2059	rpc_check_timeout(task);
2060}
2061
2062/*
2063 * 4b.	Connect to the RPC server
2064 */
2065static void
2066call_connect(struct rpc_task *task)
2067{
2068	struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2069
2070	if (rpc_task_transmitted(task)) {
2071		rpc_task_handle_transmitted(task);
2072		return;
2073	}
2074
2075	if (xprt_connected(xprt)) {
2076		task->tk_action = call_transmit;
2077		return;
2078	}
2079
2080	dprintk("RPC: %5u call_connect xprt %p %s connected\n",
2081			task->tk_pid, xprt,
2082			(xprt_connected(xprt) ? "is" : "is not"));
2083
2084	task->tk_action = call_connect_status;
2085	if (task->tk_status < 0)
2086		return;
2087	if (task->tk_flags & RPC_TASK_NOCONNECT) {
2088		rpc_call_rpcerror(task, -ENOTCONN);
2089		return;
2090	}
2091	if (!xprt_prepare_transmit(task))
2092		return;
2093	xprt_connect(task);
2094}
2095
2096/*
2097 * 4c.	Sort out connect result
2098 */
2099static void
2100call_connect_status(struct rpc_task *task)
2101{
2102	struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2103	struct rpc_clnt *clnt = task->tk_client;
2104	int status = task->tk_status;
2105
2106	if (rpc_task_transmitted(task)) {
2107		rpc_task_handle_transmitted(task);
2108		return;
2109	}
2110
2111	dprint_status(task);
2112	trace_rpc_connect_status(task);
2113
2114	if (task->tk_status == 0) {
2115		clnt->cl_stats->netreconn++;
2116		goto out_next;
2117	}
2118	if (xprt_connected(xprt)) {
2119		task->tk_status = 0;
2120		goto out_next;
2121	}
2122
2123	task->tk_status = 0;
2124	switch (status) {
2125	case -ECONNREFUSED:
 
2126		/* A positive refusal suggests a rebind is needed. */
2127		if (RPC_IS_SOFTCONN(task))
2128			break;
2129		if (clnt->cl_autobind) {
2130			rpc_force_rebind(clnt);
2131			goto out_retry;
2132		}
2133		/* fall through */
2134	case -ECONNRESET:
2135	case -ECONNABORTED:
2136	case -ENETDOWN:
2137	case -ENETUNREACH:
2138	case -EHOSTUNREACH:
2139	case -EPIPE:
 
2140		xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2141					    task->tk_rqstp->rq_connect_cookie);
2142		if (RPC_IS_SOFTCONN(task))
2143			break;
2144		/* retry with existing socket, after a delay */
2145		rpc_delay(task, 3*HZ);
2146		/* fall through */
2147	case -EADDRINUSE:
2148	case -ENOTCONN:
2149	case -EAGAIN:
2150	case -ETIMEDOUT:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2151		goto out_retry;
2152	case -ENOBUFS:
2153		rpc_delay(task, HZ >> 2);
2154		goto out_retry;
2155	}
2156	rpc_call_rpcerror(task, status);
2157	return;
2158out_next:
2159	task->tk_action = call_transmit;
2160	return;
2161out_retry:
2162	/* Check for timeouts before looping back to call_bind */
2163	task->tk_action = call_bind;
 
2164	rpc_check_timeout(task);
2165}
2166
2167/*
2168 * 5.	Transmit the RPC request, and wait for reply
2169 */
2170static void
2171call_transmit(struct rpc_task *task)
2172{
2173	if (rpc_task_transmitted(task)) {
2174		rpc_task_handle_transmitted(task);
2175		return;
2176	}
2177
2178	dprint_status(task);
2179
2180	task->tk_action = call_transmit_status;
2181	if (!xprt_prepare_transmit(task))
2182		return;
2183	task->tk_status = 0;
2184	if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2185		if (!xprt_connected(task->tk_xprt)) {
2186			task->tk_status = -ENOTCONN;
2187			return;
2188		}
2189		xprt_transmit(task);
2190	}
2191	xprt_end_transmit(task);
2192}
2193
2194/*
2195 * 5a.	Handle cleanup after a transmission
2196 */
2197static void
2198call_transmit_status(struct rpc_task *task)
2199{
2200	task->tk_action = call_status;
2201
2202	/*
2203	 * Common case: success.  Force the compiler to put this
2204	 * test first.
2205	 */
2206	if (rpc_task_transmitted(task)) {
2207		task->tk_status = 0;
2208		xprt_request_wait_receive(task);
2209		return;
2210	}
2211
2212	switch (task->tk_status) {
2213	default:
2214		dprint_status(task);
2215		break;
2216	case -EBADMSG:
2217		task->tk_status = 0;
2218		task->tk_action = call_encode;
2219		break;
2220		/*
2221		 * Special cases: if we've been waiting on the
2222		 * socket's write_space() callback, or if the
2223		 * socket just returned a connection error,
2224		 * then hold onto the transport lock.
2225		 */
 
2226	case -ENOBUFS:
2227		rpc_delay(task, HZ>>2);
2228		/* fall through */
2229	case -EBADSLT:
2230	case -EAGAIN:
2231		task->tk_action = call_transmit;
2232		task->tk_status = 0;
2233		break;
2234	case -ECONNREFUSED:
2235	case -EHOSTDOWN:
2236	case -ENETDOWN:
2237	case -EHOSTUNREACH:
2238	case -ENETUNREACH:
2239	case -EPERM:
 
 
2240		if (RPC_IS_SOFTCONN(task)) {
2241			if (!task->tk_msg.rpc_proc->p_proc)
2242				trace_xprt_ping(task->tk_xprt,
2243						task->tk_status);
2244			rpc_call_rpcerror(task, task->tk_status);
2245			return;
2246		}
2247		/* fall through */
2248	case -ECONNRESET:
2249	case -ECONNABORTED:
2250	case -EADDRINUSE:
2251	case -ENOTCONN:
2252	case -EPIPE:
2253		task->tk_action = call_bind;
2254		task->tk_status = 0;
2255		break;
2256	}
2257	rpc_check_timeout(task);
2258}
2259
2260#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2261static void call_bc_transmit(struct rpc_task *task);
2262static void call_bc_transmit_status(struct rpc_task *task);
2263
2264static void
2265call_bc_encode(struct rpc_task *task)
2266{
2267	xprt_request_enqueue_transmit(task);
2268	task->tk_action = call_bc_transmit;
2269}
2270
2271/*
2272 * 5b.	Send the backchannel RPC reply.  On error, drop the reply.  In
2273 * addition, disconnect on connectivity errors.
2274 */
2275static void
2276call_bc_transmit(struct rpc_task *task)
2277{
2278	task->tk_action = call_bc_transmit_status;
2279	if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2280		if (!xprt_prepare_transmit(task))
2281			return;
2282		task->tk_status = 0;
2283		xprt_transmit(task);
2284	}
2285	xprt_end_transmit(task);
2286}
2287
2288static void
2289call_bc_transmit_status(struct rpc_task *task)
2290{
2291	struct rpc_rqst *req = task->tk_rqstp;
2292
2293	if (rpc_task_transmitted(task))
2294		task->tk_status = 0;
2295
2296	dprint_status(task);
2297
2298	switch (task->tk_status) {
2299	case 0:
2300		/* Success */
2301	case -ENETDOWN:
2302	case -EHOSTDOWN:
2303	case -EHOSTUNREACH:
2304	case -ENETUNREACH:
2305	case -ECONNRESET:
2306	case -ECONNREFUSED:
2307	case -EADDRINUSE:
2308	case -ENOTCONN:
2309	case -EPIPE:
2310		break;
 
2311	case -ENOBUFS:
2312		rpc_delay(task, HZ>>2);
2313		/* fall through */
2314	case -EBADSLT:
2315	case -EAGAIN:
2316		task->tk_status = 0;
2317		task->tk_action = call_bc_transmit;
2318		return;
2319	case -ETIMEDOUT:
2320		/*
2321		 * Problem reaching the server.  Disconnect and let the
2322		 * forechannel reestablish the connection.  The server will
2323		 * have to retransmit the backchannel request and we'll
2324		 * reprocess it.  Since these ops are idempotent, there's no
2325		 * need to cache our reply at this time.
2326		 */
2327		printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2328			"error: %d\n", task->tk_status);
2329		xprt_conditional_disconnect(req->rq_xprt,
2330			req->rq_connect_cookie);
2331		break;
2332	default:
2333		/*
2334		 * We were unable to reply and will have to drop the
2335		 * request.  The server should reconnect and retransmit.
2336		 */
2337		printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2338			"error: %d\n", task->tk_status);
2339		break;
2340	}
2341	task->tk_action = rpc_exit_task;
2342}
2343#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2344
2345/*
2346 * 6.	Sort out the RPC call status
2347 */
2348static void
2349call_status(struct rpc_task *task)
2350{
2351	struct rpc_clnt	*clnt = task->tk_client;
2352	int		status;
2353
2354	if (!task->tk_msg.rpc_proc->p_proc)
2355		trace_xprt_ping(task->tk_xprt, task->tk_status);
2356
2357	dprint_status(task);
2358
2359	status = task->tk_status;
2360	if (status >= 0) {
2361		task->tk_action = call_decode;
2362		return;
2363	}
2364
2365	trace_rpc_call_status(task);
2366	task->tk_status = 0;
2367	switch(status) {
2368	case -EHOSTDOWN:
2369	case -ENETDOWN:
2370	case -EHOSTUNREACH:
2371	case -ENETUNREACH:
2372	case -EPERM:
2373		if (RPC_IS_SOFTCONN(task))
2374			goto out_exit;
2375		/*
2376		 * Delay any retries for 3 seconds, then handle as if it
2377		 * were a timeout.
2378		 */
2379		rpc_delay(task, 3*HZ);
2380		/* fall through */
2381	case -ETIMEDOUT:
2382		break;
2383	case -ECONNREFUSED:
2384	case -ECONNRESET:
2385	case -ECONNABORTED:
2386	case -ENOTCONN:
2387		rpc_force_rebind(clnt);
2388		break;
2389	case -EADDRINUSE:
2390		rpc_delay(task, 3*HZ);
2391		/* fall through */
2392	case -EPIPE:
2393	case -EAGAIN:
2394		break;
 
 
 
 
 
2395	case -EIO:
2396		/* shutdown or soft timeout */
2397		goto out_exit;
2398	default:
2399		if (clnt->cl_chatty)
2400			printk("%s: RPC call returned error %d\n",
2401			       clnt->cl_program->name, -status);
2402		goto out_exit;
2403	}
2404	task->tk_action = call_encode;
2405	rpc_check_timeout(task);
2406	return;
2407out_exit:
2408	rpc_call_rpcerror(task, status);
2409}
2410
2411static bool
2412rpc_check_connected(const struct rpc_rqst *req)
2413{
2414	/* No allocated request or transport? return true */
2415	if (!req || !req->rq_xprt)
2416		return true;
2417	return xprt_connected(req->rq_xprt);
2418}
2419
2420static void
2421rpc_check_timeout(struct rpc_task *task)
2422{
2423	struct rpc_clnt	*clnt = task->tk_client;
2424
 
 
 
2425	if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2426		return;
2427
2428	dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2429	task->tk_timeouts++;
2430
2431	if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2432		rpc_call_rpcerror(task, -ETIMEDOUT);
2433		return;
2434	}
2435
2436	if (RPC_IS_SOFT(task)) {
2437		/*
2438		 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2439		 * been sent, it should time out only if the transport
2440		 * connection gets terminally broken.
2441		 */
2442		if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2443		    rpc_check_connected(task->tk_rqstp))
2444			return;
2445
2446		if (clnt->cl_chatty) {
2447			pr_notice_ratelimited(
2448				"%s: server %s not responding, timed out\n",
2449				clnt->cl_program->name,
2450				task->tk_xprt->servername);
2451		}
2452		if (task->tk_flags & RPC_TASK_TIMEOUT)
2453			rpc_call_rpcerror(task, -ETIMEDOUT);
2454		else
2455			__rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2456		return;
2457	}
2458
2459	if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2460		task->tk_flags |= RPC_CALL_MAJORSEEN;
2461		if (clnt->cl_chatty) {
2462			pr_notice_ratelimited(
2463				"%s: server %s not responding, still trying\n",
2464				clnt->cl_program->name,
2465				task->tk_xprt->servername);
2466		}
2467	}
2468	rpc_force_rebind(clnt);
2469	/*
2470	 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2471	 * event? RFC2203 requires the server to drop all such requests.
2472	 */
2473	rpcauth_invalcred(task);
2474}
2475
2476/*
2477 * 7.	Decode the RPC reply
2478 */
2479static void
2480call_decode(struct rpc_task *task)
2481{
2482	struct rpc_clnt	*clnt = task->tk_client;
2483	struct rpc_rqst	*req = task->tk_rqstp;
2484	struct xdr_stream xdr;
2485	int err;
2486
2487	dprint_status(task);
2488
2489	if (!task->tk_msg.rpc_proc->p_decode) {
2490		task->tk_action = rpc_exit_task;
2491		return;
2492	}
2493
2494	if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2495		if (clnt->cl_chatty) {
2496			pr_notice_ratelimited("%s: server %s OK\n",
2497				clnt->cl_program->name,
2498				task->tk_xprt->servername);
2499		}
2500		task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2501	}
2502
2503	/*
2504	 * Ensure that we see all writes made by xprt_complete_rqst()
2505	 * before it changed req->rq_reply_bytes_recvd.
2506	 */
2507	smp_rmb();
2508
2509	/*
2510	 * Did we ever call xprt_complete_rqst()? If not, we should assume
2511	 * the message is incomplete.
2512	 */
2513	err = -EAGAIN;
2514	if (!req->rq_reply_bytes_recvd)
2515		goto out;
2516
 
 
 
 
 
2517	req->rq_rcv_buf.len = req->rq_private_buf.len;
 
2518
2519	/* Check that the softirq receive buffer is valid */
2520	WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2521				sizeof(req->rq_rcv_buf)) != 0);
2522
2523	xdr_init_decode(&xdr, &req->rq_rcv_buf,
2524			req->rq_rcv_buf.head[0].iov_base, req);
2525	err = rpc_decode_header(task, &xdr);
2526out:
2527	switch (err) {
2528	case 0:
2529		task->tk_action = rpc_exit_task;
2530		task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2531		dprintk("RPC: %5u %s result %d\n",
2532			task->tk_pid, __func__, task->tk_status);
2533		return;
2534	case -EAGAIN:
2535		task->tk_status = 0;
2536		if (task->tk_client->cl_discrtry)
2537			xprt_conditional_disconnect(req->rq_xprt,
2538						    req->rq_connect_cookie);
2539		task->tk_action = call_encode;
2540		rpc_check_timeout(task);
2541		break;
2542	case -EKEYREJECTED:
2543		task->tk_action = call_reserve;
2544		rpc_check_timeout(task);
2545		rpcauth_invalcred(task);
2546		/* Ensure we obtain a new XID if we retry! */
2547		xprt_release(task);
2548	}
2549}
2550
2551static int
2552rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2553{
2554	struct rpc_clnt *clnt = task->tk_client;
2555	struct rpc_rqst	*req = task->tk_rqstp;
2556	__be32 *p;
2557	int error;
2558
2559	error = -EMSGSIZE;
2560	p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2561	if (!p)
2562		goto out_fail;
2563	*p++ = req->rq_xid;
2564	*p++ = rpc_call;
2565	*p++ = cpu_to_be32(RPC_VERSION);
2566	*p++ = cpu_to_be32(clnt->cl_prog);
2567	*p++ = cpu_to_be32(clnt->cl_vers);
2568	*p   = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2569
2570	error = rpcauth_marshcred(task, xdr);
2571	if (error < 0)
2572		goto out_fail;
2573	return 0;
2574out_fail:
2575	trace_rpc_bad_callhdr(task);
2576	rpc_call_rpcerror(task, error);
2577	return error;
2578}
2579
2580static noinline int
2581rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2582{
2583	struct rpc_clnt *clnt = task->tk_client;
2584	int error;
2585	__be32 *p;
2586
2587	/* RFC-1014 says that the representation of XDR data must be a
2588	 * multiple of four bytes
2589	 * - if it isn't pointer subtraction in the NFS client may give
2590	 *   undefined results
2591	 */
2592	if (task->tk_rqstp->rq_rcv_buf.len & 3)
2593		goto out_unparsable;
2594
2595	p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2596	if (!p)
2597		goto out_unparsable;
2598	p++;	/* skip XID */
2599	if (*p++ != rpc_reply)
2600		goto out_unparsable;
2601	if (*p++ != rpc_msg_accepted)
2602		goto out_msg_denied;
2603
2604	error = rpcauth_checkverf(task, xdr);
2605	if (error)
 
 
 
 
 
 
 
 
 
 
2606		goto out_verifier;
 
2607
2608	p = xdr_inline_decode(xdr, sizeof(*p));
2609	if (!p)
2610		goto out_unparsable;
2611	switch (*p) {
2612	case rpc_success:
2613		return 0;
2614	case rpc_prog_unavail:
2615		trace_rpc__prog_unavail(task);
2616		error = -EPFNOSUPPORT;
2617		goto out_err;
2618	case rpc_prog_mismatch:
2619		trace_rpc__prog_mismatch(task);
2620		error = -EPROTONOSUPPORT;
2621		goto out_err;
2622	case rpc_proc_unavail:
2623		trace_rpc__proc_unavail(task);
2624		error = -EOPNOTSUPP;
2625		goto out_err;
2626	case rpc_garbage_args:
2627	case rpc_system_err:
2628		trace_rpc__garbage_args(task);
2629		error = -EIO;
2630		break;
2631	default:
2632		goto out_unparsable;
2633	}
2634
2635out_garbage:
2636	clnt->cl_stats->rpcgarbage++;
2637	if (task->tk_garb_retry) {
2638		task->tk_garb_retry--;
2639		task->tk_action = call_encode;
2640		return -EAGAIN;
2641	}
2642out_err:
2643	rpc_call_rpcerror(task, error);
2644	return error;
2645
2646out_unparsable:
2647	trace_rpc__unparsable(task);
2648	error = -EIO;
2649	goto out_garbage;
2650
2651out_verifier:
2652	trace_rpc_bad_verifier(task);
2653	goto out_garbage;
 
 
 
 
 
 
 
 
2654
2655out_msg_denied:
2656	error = -EACCES;
2657	p = xdr_inline_decode(xdr, sizeof(*p));
2658	if (!p)
2659		goto out_unparsable;
2660	switch (*p++) {
2661	case rpc_auth_error:
2662		break;
2663	case rpc_mismatch:
2664		trace_rpc__mismatch(task);
2665		error = -EPROTONOSUPPORT;
2666		goto out_err;
2667	default:
2668		goto out_unparsable;
2669	}
2670
2671	p = xdr_inline_decode(xdr, sizeof(*p));
2672	if (!p)
2673		goto out_unparsable;
2674	switch (*p++) {
2675	case rpc_autherr_rejectedcred:
2676	case rpc_autherr_rejectedverf:
2677	case rpcsec_gsserr_credproblem:
2678	case rpcsec_gsserr_ctxproblem:
 
2679		if (!task->tk_cred_retry)
2680			break;
2681		task->tk_cred_retry--;
2682		trace_rpc__stale_creds(task);
2683		return -EKEYREJECTED;
2684	case rpc_autherr_badcred:
2685	case rpc_autherr_badverf:
2686		/* possibly garbled cred/verf? */
2687		if (!task->tk_garb_retry)
2688			break;
2689		task->tk_garb_retry--;
2690		trace_rpc__bad_creds(task);
2691		task->tk_action = call_encode;
2692		return -EAGAIN;
2693	case rpc_autherr_tooweak:
2694		trace_rpc__auth_tooweak(task);
2695		pr_warn("RPC: server %s requires stronger authentication.\n",
2696			task->tk_xprt->servername);
2697		break;
2698	default:
2699		goto out_unparsable;
2700	}
2701	goto out_err;
2702}
2703
2704static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2705		const void *obj)
2706{
2707}
2708
2709static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2710		void *obj)
2711{
2712	return 0;
2713}
2714
2715static const struct rpc_procinfo rpcproc_null = {
2716	.p_encode = rpcproc_encode_null,
2717	.p_decode = rpcproc_decode_null,
2718};
2719
2720static int rpc_ping(struct rpc_clnt *clnt)
 
 
 
 
 
2721{
2722	struct rpc_message msg = {
2723		.rpc_proc = &rpcproc_null,
2724	};
2725	int err;
2726	err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2727			    RPC_TASK_NULLCREDS);
2728	return err;
2729}
2730
 
 
 
 
 
2731static
2732struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2733		struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2734		const struct rpc_call_ops *ops, void *data)
2735{
2736	struct rpc_message msg = {
2737		.rpc_proc = &rpcproc_null,
2738	};
2739	struct rpc_task_setup task_setup_data = {
2740		.rpc_client = clnt,
2741		.rpc_xprt = xprt,
2742		.rpc_message = &msg,
2743		.rpc_op_cred = cred,
2744		.callback_ops = (ops != NULL) ? ops : &rpc_default_ops,
2745		.callback_data = data,
2746		.flags = flags | RPC_TASK_NULLCREDS,
 
2747	};
2748
2749	return rpc_run_task(&task_setup_data);
2750}
2751
2752struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2753{
2754	return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2755}
2756EXPORT_SYMBOL_GPL(rpc_call_null);
2757
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2758struct rpc_cb_add_xprt_calldata {
2759	struct rpc_xprt_switch *xps;
2760	struct rpc_xprt *xprt;
2761};
2762
2763static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2764{
2765	struct rpc_cb_add_xprt_calldata *data = calldata;
2766
2767	if (task->tk_status == 0)
2768		rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2769}
2770
2771static void rpc_cb_add_xprt_release(void *calldata)
2772{
2773	struct rpc_cb_add_xprt_calldata *data = calldata;
2774
2775	xprt_put(data->xprt);
2776	xprt_switch_put(data->xps);
2777	kfree(data);
2778}
2779
2780static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
 
2781	.rpc_call_done = rpc_cb_add_xprt_done,
2782	.rpc_release = rpc_cb_add_xprt_release,
2783};
2784
2785/**
2786 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2787 * @clnt: pointer to struct rpc_clnt
2788 * @xps: pointer to struct rpc_xprt_switch,
2789 * @xprt: pointer struct rpc_xprt
2790 * @dummy: unused
2791 */
2792int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2793		struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2794		void *dummy)
2795{
2796	struct rpc_cb_add_xprt_calldata *data;
2797	struct rpc_task *task;
 
2798
2799	data = kmalloc(sizeof(*data), GFP_NOFS);
 
 
 
 
 
 
 
 
 
 
 
2800	if (!data)
2801		return -ENOMEM;
2802	data->xps = xprt_switch_get(xps);
2803	data->xprt = xprt_get(xprt);
2804	if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2805		rpc_cb_add_xprt_release(data);
2806		goto success;
2807	}
2808
2809	task = rpc_call_null_helper(clnt, xprt, NULL,
2810			RPC_TASK_SOFT|RPC_TASK_SOFTCONN|RPC_TASK_ASYNC|RPC_TASK_NULLCREDS,
2811			&rpc_cb_add_xprt_call_ops, data);
2812	if (IS_ERR(task))
2813		return PTR_ERR(task);
 
 
2814	rpc_put_task(task);
2815success:
2816	return 1;
2817}
2818EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2819
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2820/**
2821 * rpc_clnt_setup_test_and_add_xprt()
2822 *
2823 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
2824 *   1) caller of the test function must dereference the rpc_xprt_switch
2825 *   and the rpc_xprt.
2826 *   2) test function must call rpc_xprt_switch_add_xprt, usually in
2827 *   the rpc_call_done routine.
2828 *
2829 * Upon success (return of 1), the test function adds the new
2830 * transport to the rpc_clnt xprt switch
2831 *
2832 * @clnt: struct rpc_clnt to get the new transport
2833 * @xps:  the rpc_xprt_switch to hold the new transport
2834 * @xprt: the rpc_xprt to test
2835 * @data: a struct rpc_add_xprt_test pointer that holds the test function
2836 *        and test function call data
2837 */
2838int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
2839				     struct rpc_xprt_switch *xps,
2840				     struct rpc_xprt *xprt,
2841				     void *data)
2842{
2843	struct rpc_task *task;
2844	struct rpc_add_xprt_test *xtest = (struct rpc_add_xprt_test *)data;
2845	int status = -EADDRINUSE;
2846
2847	xprt = xprt_get(xprt);
2848	xprt_switch_get(xps);
2849
2850	if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
2851		goto out_err;
2852
2853	/* Test the connection */
2854	task = rpc_call_null_helper(clnt, xprt, NULL,
2855				    RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2856				    NULL, NULL);
2857	if (IS_ERR(task)) {
2858		status = PTR_ERR(task);
2859		goto out_err;
2860	}
2861	status = task->tk_status;
2862	rpc_put_task(task);
2863
2864	if (status < 0)
2865		goto out_err;
2866
2867	/* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2868	xtest->add_xprt_test(clnt, xprt, xtest->data);
2869
2870	xprt_put(xprt);
2871	xprt_switch_put(xps);
2872
2873	/* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
2874	return 1;
2875out_err:
2876	xprt_put(xprt);
2877	xprt_switch_put(xps);
2878	pr_info("RPC:   rpc_clnt_test_xprt failed: %d addr %s not added\n",
2879		status, xprt->address_strings[RPC_DISPLAY_ADDR]);
 
 
 
2880	return status;
2881}
2882EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
2883
2884/**
2885 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
2886 * @clnt: pointer to struct rpc_clnt
2887 * @xprtargs: pointer to struct xprt_create
2888 * @setup: callback to test and/or set up the connection
2889 * @data: pointer to setup function data
2890 *
2891 * Creates a new transport using the parameters set in args and
2892 * adds it to clnt.
2893 * If ping is set, then test that connectivity succeeds before
2894 * adding the new transport.
2895 *
2896 */
2897int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
2898		struct xprt_create *xprtargs,
2899		int (*setup)(struct rpc_clnt *,
2900			struct rpc_xprt_switch *,
2901			struct rpc_xprt *,
2902			void *),
2903		void *data)
2904{
2905	struct rpc_xprt_switch *xps;
2906	struct rpc_xprt *xprt;
2907	unsigned long connect_timeout;
2908	unsigned long reconnect_timeout;
2909	unsigned char resvport;
2910	int ret = 0;
2911
2912	rcu_read_lock();
2913	xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2914	xprt = xprt_iter_xprt(&clnt->cl_xpi);
2915	if (xps == NULL || xprt == NULL) {
2916		rcu_read_unlock();
2917		xprt_switch_put(xps);
2918		return -EAGAIN;
2919	}
2920	resvport = xprt->resvport;
 
2921	connect_timeout = xprt->connect_timeout;
2922	reconnect_timeout = xprt->max_reconnect_timeout;
 
2923	rcu_read_unlock();
2924
 
 
 
2925	xprt = xprt_create_transport(xprtargs);
2926	if (IS_ERR(xprt)) {
2927		ret = PTR_ERR(xprt);
2928		goto out_put_switch;
2929	}
2930	xprt->resvport = resvport;
 
 
 
 
 
 
2931	if (xprt->ops->set_connect_timeout != NULL)
2932		xprt->ops->set_connect_timeout(xprt,
2933				connect_timeout,
2934				reconnect_timeout);
2935
2936	rpc_xprt_switch_set_roundrobin(xps);
2937	if (setup) {
2938		ret = setup(clnt, xps, xprt, data);
2939		if (ret != 0)
2940			goto out_put_xprt;
2941	}
2942	rpc_xprt_switch_add_xprt(xps, xprt);
2943out_put_xprt:
2944	xprt_put(xprt);
2945out_put_switch:
2946	xprt_switch_put(xps);
2947	return ret;
2948}
2949EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
2950
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2951struct connect_timeout_data {
2952	unsigned long connect_timeout;
2953	unsigned long reconnect_timeout;
2954};
2955
2956static int
2957rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
2958		struct rpc_xprt *xprt,
2959		void *data)
2960{
2961	struct connect_timeout_data *timeo = data;
2962
2963	if (xprt->ops->set_connect_timeout)
2964		xprt->ops->set_connect_timeout(xprt,
2965				timeo->connect_timeout,
2966				timeo->reconnect_timeout);
2967	return 0;
2968}
2969
2970void
2971rpc_set_connect_timeout(struct rpc_clnt *clnt,
2972		unsigned long connect_timeout,
2973		unsigned long reconnect_timeout)
2974{
2975	struct connect_timeout_data timeout = {
2976		.connect_timeout = connect_timeout,
2977		.reconnect_timeout = reconnect_timeout,
2978	};
2979	rpc_clnt_iterate_for_each_xprt(clnt,
2980			rpc_xprt_set_connect_timeout,
2981			&timeout);
2982}
2983EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
2984
2985void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt)
2986{
2987	rcu_read_lock();
2988	xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2989	rcu_read_unlock();
 
 
2990}
2991EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put);
2992
2993void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
2994{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2995	rcu_read_lock();
2996	rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
2997				 xprt);
 
 
2998	rcu_read_unlock();
2999}
3000EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3001
3002bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3003				   const struct sockaddr *sap)
3004{
3005	struct rpc_xprt_switch *xps;
3006	bool ret;
3007
3008	rcu_read_lock();
3009	xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3010	ret = rpc_xprt_switch_has_addr(xps, sap);
3011	rcu_read_unlock();
3012	return ret;
3013}
3014EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3015
3016#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3017static void rpc_show_header(void)
3018{
3019	printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3020		"-timeout ---ops--\n");
3021}
3022
3023static void rpc_show_task(const struct rpc_clnt *clnt,
3024			  const struct rpc_task *task)
3025{
3026	const char *rpc_waitq = "none";
3027
3028	if (RPC_IS_QUEUED(task))
3029		rpc_waitq = rpc_qname(task->tk_waitqueue);
3030
3031	printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3032		task->tk_pid, task->tk_flags, task->tk_status,
3033		clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3034		clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3035		task->tk_action, rpc_waitq);
3036}
3037
3038void rpc_show_tasks(struct net *net)
3039{
3040	struct rpc_clnt *clnt;
3041	struct rpc_task *task;
3042	int header = 0;
3043	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3044
3045	spin_lock(&sn->rpc_client_lock);
3046	list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3047		spin_lock(&clnt->cl_lock);
3048		list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3049			if (!header) {
3050				rpc_show_header();
3051				header++;
3052			}
3053			rpc_show_task(clnt, task);
3054		}
3055		spin_unlock(&clnt->cl_lock);
3056	}
3057	spin_unlock(&sn->rpc_client_lock);
3058}
3059#endif
3060
3061#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3062static int
3063rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3064		struct rpc_xprt *xprt,
3065		void *dummy)
3066{
3067	return xprt_enable_swap(xprt);
3068}
3069
3070int
3071rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3072{
 
 
3073	if (atomic_inc_return(&clnt->cl_swapper) == 1)
3074		return rpc_clnt_iterate_for_each_xprt(clnt,
3075				rpc_clnt_swap_activate_callback, NULL);
3076	return 0;
3077}
3078EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3079
3080static int
3081rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3082		struct rpc_xprt *xprt,
3083		void *dummy)
3084{
3085	xprt_disable_swap(xprt);
3086	return 0;
3087}
3088
3089void
3090rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3091{
 
 
3092	if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3093		rpc_clnt_iterate_for_each_xprt(clnt,
3094				rpc_clnt_swap_deactivate_callback, NULL);
3095}
3096EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3097#endif /* CONFIG_SUNRPC_SWAP */
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  linux/net/sunrpc/clnt.c
   4 *
   5 *  This file contains the high-level RPC interface.
   6 *  It is modeled as a finite state machine to support both synchronous
   7 *  and asynchronous requests.
   8 *
   9 *  -	RPC header generation and argument serialization.
  10 *  -	Credential refresh.
  11 *  -	TCP connect handling.
  12 *  -	Retry of operation when it is suspected the operation failed because
  13 *	of uid squashing on the server, or when the credentials were stale
  14 *	and need to be refreshed, or when a packet was damaged in transit.
  15 *	This may be have to be moved to the VFS layer.
  16 *
  17 *  Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
  18 *  Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
  19 */
  20
  21
  22#include <linux/module.h>
  23#include <linux/types.h>
  24#include <linux/kallsyms.h>
  25#include <linux/mm.h>
  26#include <linux/namei.h>
  27#include <linux/mount.h>
  28#include <linux/slab.h>
  29#include <linux/rcupdate.h>
  30#include <linux/utsname.h>
  31#include <linux/workqueue.h>
  32#include <linux/in.h>
  33#include <linux/in6.h>
  34#include <linux/un.h>
  35
  36#include <linux/sunrpc/clnt.h>
  37#include <linux/sunrpc/addr.h>
  38#include <linux/sunrpc/rpc_pipe_fs.h>
  39#include <linux/sunrpc/metrics.h>
  40#include <linux/sunrpc/bc_xprt.h>
  41#include <trace/events/sunrpc.h>
  42
  43#include "sunrpc.h"
  44#include "sysfs.h"
  45#include "netns.h"
  46
  47#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  48# define RPCDBG_FACILITY	RPCDBG_CALL
  49#endif
  50
 
 
 
 
 
 
 
 
  51static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
  52
 
  53static void	call_start(struct rpc_task *task);
  54static void	call_reserve(struct rpc_task *task);
  55static void	call_reserveresult(struct rpc_task *task);
  56static void	call_allocate(struct rpc_task *task);
  57static void	call_encode(struct rpc_task *task);
  58static void	call_decode(struct rpc_task *task);
  59static void	call_bind(struct rpc_task *task);
  60static void	call_bind_status(struct rpc_task *task);
  61static void	call_transmit(struct rpc_task *task);
  62static void	call_status(struct rpc_task *task);
  63static void	call_transmit_status(struct rpc_task *task);
  64static void	call_refresh(struct rpc_task *task);
  65static void	call_refreshresult(struct rpc_task *task);
  66static void	call_connect(struct rpc_task *task);
  67static void	call_connect_status(struct rpc_task *task);
  68
  69static int	rpc_encode_header(struct rpc_task *task,
  70				  struct xdr_stream *xdr);
  71static int	rpc_decode_header(struct rpc_task *task,
  72				  struct xdr_stream *xdr);
  73static int	rpc_ping(struct rpc_clnt *clnt);
  74static int	rpc_ping_noreply(struct rpc_clnt *clnt);
  75static void	rpc_check_timeout(struct rpc_task *task);
  76
  77static void rpc_register_client(struct rpc_clnt *clnt)
  78{
  79	struct net *net = rpc_net_ns(clnt);
  80	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
  81
  82	spin_lock(&sn->rpc_client_lock);
  83	list_add(&clnt->cl_clients, &sn->all_clients);
  84	spin_unlock(&sn->rpc_client_lock);
  85}
  86
  87static void rpc_unregister_client(struct rpc_clnt *clnt)
  88{
  89	struct net *net = rpc_net_ns(clnt);
  90	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
  91
  92	spin_lock(&sn->rpc_client_lock);
  93	list_del(&clnt->cl_clients);
  94	spin_unlock(&sn->rpc_client_lock);
  95}
  96
  97static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
  98{
  99	rpc_remove_client_dir(clnt);
 100}
 101
 102static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
 103{
 104	struct net *net = rpc_net_ns(clnt);
 105	struct super_block *pipefs_sb;
 106
 107	pipefs_sb = rpc_get_sb_net(net);
 108	if (pipefs_sb) {
 109		if (pipefs_sb == clnt->pipefs_sb)
 110			__rpc_clnt_remove_pipedir(clnt);
 111		rpc_put_sb_net(net);
 112	}
 113}
 114
 115static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
 116				    struct rpc_clnt *clnt)
 117{
 118	static uint32_t clntid;
 119	const char *dir_name = clnt->cl_program->pipe_dir_name;
 120	char name[15];
 121	struct dentry *dir, *dentry;
 122
 123	dir = rpc_d_lookup_sb(sb, dir_name);
 124	if (dir == NULL) {
 125		pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
 126		return dir;
 127	}
 128	for (;;) {
 129		snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
 130		name[sizeof(name) - 1] = '\0';
 131		dentry = rpc_create_client_dir(dir, name, clnt);
 132		if (!IS_ERR(dentry))
 133			break;
 134		if (dentry == ERR_PTR(-EEXIST))
 135			continue;
 136		printk(KERN_INFO "RPC: Couldn't create pipefs entry"
 137				" %s/%s, error %ld\n",
 138				dir_name, name, PTR_ERR(dentry));
 139		break;
 140	}
 141	dput(dir);
 142	return dentry;
 143}
 144
 145static int
 146rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
 147{
 148	struct dentry *dentry;
 149
 150	clnt->pipefs_sb = pipefs_sb;
 151
 152	if (clnt->cl_program->pipe_dir_name != NULL) {
 153		dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
 154		if (IS_ERR(dentry))
 155			return PTR_ERR(dentry);
 156	}
 157	return 0;
 158}
 159
 160static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
 161{
 162	if (clnt->cl_program->pipe_dir_name == NULL)
 163		return 1;
 164
 165	switch (event) {
 166	case RPC_PIPEFS_MOUNT:
 167		if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
 168			return 1;
 169		if (refcount_read(&clnt->cl_count) == 0)
 170			return 1;
 171		break;
 172	case RPC_PIPEFS_UMOUNT:
 173		if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
 174			return 1;
 175		break;
 176	}
 177	return 0;
 178}
 179
 180static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
 181				   struct super_block *sb)
 182{
 183	struct dentry *dentry;
 184
 185	switch (event) {
 186	case RPC_PIPEFS_MOUNT:
 187		dentry = rpc_setup_pipedir_sb(sb, clnt);
 188		if (!dentry)
 189			return -ENOENT;
 190		if (IS_ERR(dentry))
 191			return PTR_ERR(dentry);
 192		break;
 193	case RPC_PIPEFS_UMOUNT:
 194		__rpc_clnt_remove_pipedir(clnt);
 195		break;
 196	default:
 197		printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
 198		return -ENOTSUPP;
 199	}
 200	return 0;
 201}
 202
 203static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
 204				struct super_block *sb)
 205{
 206	int error = 0;
 207
 208	for (;; clnt = clnt->cl_parent) {
 209		if (!rpc_clnt_skip_event(clnt, event))
 210			error = __rpc_clnt_handle_event(clnt, event, sb);
 211		if (error || clnt == clnt->cl_parent)
 212			break;
 213	}
 214	return error;
 215}
 216
 217static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
 218{
 219	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 220	struct rpc_clnt *clnt;
 221
 222	spin_lock(&sn->rpc_client_lock);
 223	list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
 224		if (rpc_clnt_skip_event(clnt, event))
 225			continue;
 226		spin_unlock(&sn->rpc_client_lock);
 227		return clnt;
 228	}
 229	spin_unlock(&sn->rpc_client_lock);
 230	return NULL;
 231}
 232
 233static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
 234			    void *ptr)
 235{
 236	struct super_block *sb = ptr;
 237	struct rpc_clnt *clnt;
 238	int error = 0;
 239
 240	while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
 241		error = __rpc_pipefs_event(clnt, event, sb);
 242		if (error)
 243			break;
 244	}
 245	return error;
 246}
 247
 248static struct notifier_block rpc_clients_block = {
 249	.notifier_call	= rpc_pipefs_event,
 250	.priority	= SUNRPC_PIPEFS_RPC_PRIO,
 251};
 252
 253int rpc_clients_notifier_register(void)
 254{
 255	return rpc_pipefs_notifier_register(&rpc_clients_block);
 256}
 257
 258void rpc_clients_notifier_unregister(void)
 259{
 260	return rpc_pipefs_notifier_unregister(&rpc_clients_block);
 261}
 262
 263static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
 264		struct rpc_xprt *xprt,
 265		const struct rpc_timeout *timeout)
 266{
 267	struct rpc_xprt *old;
 268
 269	spin_lock(&clnt->cl_lock);
 270	old = rcu_dereference_protected(clnt->cl_xprt,
 271			lockdep_is_held(&clnt->cl_lock));
 272
 273	if (!xprt_bound(xprt))
 274		clnt->cl_autobind = 1;
 275
 276	clnt->cl_timeout = timeout;
 277	rcu_assign_pointer(clnt->cl_xprt, xprt);
 278	spin_unlock(&clnt->cl_lock);
 279
 280	return old;
 281}
 282
 283static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
 284{
 285	ssize_t copied;
 286
 287	copied = strscpy(clnt->cl_nodename,
 288			 nodename, sizeof(clnt->cl_nodename));
 289
 290	clnt->cl_nodelen = copied < 0
 291				? sizeof(clnt->cl_nodename) - 1
 292				: copied;
 293}
 294
 295static int rpc_client_register(struct rpc_clnt *clnt,
 296			       rpc_authflavor_t pseudoflavor,
 297			       const char *client_name)
 298{
 299	struct rpc_auth_create_args auth_args = {
 300		.pseudoflavor = pseudoflavor,
 301		.target_name = client_name,
 302	};
 303	struct rpc_auth *auth;
 304	struct net *net = rpc_net_ns(clnt);
 305	struct super_block *pipefs_sb;
 306	int err;
 307
 308	rpc_clnt_debugfs_register(clnt);
 309
 310	pipefs_sb = rpc_get_sb_net(net);
 311	if (pipefs_sb) {
 312		err = rpc_setup_pipedir(pipefs_sb, clnt);
 313		if (err)
 314			goto out;
 315	}
 316
 317	rpc_register_client(clnt);
 318	if (pipefs_sb)
 319		rpc_put_sb_net(net);
 320
 321	auth = rpcauth_create(&auth_args, clnt);
 322	if (IS_ERR(auth)) {
 323		dprintk("RPC:       Couldn't create auth handle (flavor %u)\n",
 324				pseudoflavor);
 325		err = PTR_ERR(auth);
 326		goto err_auth;
 327	}
 328	return 0;
 329err_auth:
 330	pipefs_sb = rpc_get_sb_net(net);
 331	rpc_unregister_client(clnt);
 332	__rpc_clnt_remove_pipedir(clnt);
 333out:
 334	if (pipefs_sb)
 335		rpc_put_sb_net(net);
 336	rpc_sysfs_client_destroy(clnt);
 337	rpc_clnt_debugfs_unregister(clnt);
 338	return err;
 339}
 340
 341static DEFINE_IDA(rpc_clids);
 342
 343void rpc_cleanup_clids(void)
 344{
 345	ida_destroy(&rpc_clids);
 346}
 347
 348static int rpc_alloc_clid(struct rpc_clnt *clnt)
 349{
 350	int clid;
 351
 352	clid = ida_alloc(&rpc_clids, GFP_KERNEL);
 353	if (clid < 0)
 354		return clid;
 355	clnt->cl_clid = clid;
 356	return 0;
 357}
 358
 359static void rpc_free_clid(struct rpc_clnt *clnt)
 360{
 361	ida_free(&rpc_clids, clnt->cl_clid);
 362}
 363
 364static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
 365		struct rpc_xprt_switch *xps,
 366		struct rpc_xprt *xprt,
 367		struct rpc_clnt *parent)
 368{
 369	const struct rpc_program *program = args->program;
 370	const struct rpc_version *version;
 371	struct rpc_clnt *clnt = NULL;
 372	const struct rpc_timeout *timeout;
 373	const char *nodename = args->nodename;
 374	int err;
 375
 
 
 
 
 376	err = rpciod_up();
 377	if (err)
 378		goto out_no_rpciod;
 379
 380	err = -EINVAL;
 381	if (args->version >= program->nrvers)
 382		goto out_err;
 383	version = program->version[args->version];
 384	if (version == NULL)
 385		goto out_err;
 386
 387	err = -ENOMEM;
 388	clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
 389	if (!clnt)
 390		goto out_err;
 391	clnt->cl_parent = parent ? : clnt;
 392	clnt->cl_xprtsec = args->xprtsec;
 393
 394	err = rpc_alloc_clid(clnt);
 395	if (err)
 396		goto out_no_clid;
 397
 398	clnt->cl_cred	  = get_cred(args->cred);
 399	clnt->cl_procinfo = version->procs;
 400	clnt->cl_maxproc  = version->nrprocs;
 401	clnt->cl_prog     = args->prognumber ? : program->number;
 402	clnt->cl_vers     = version->number;
 403	clnt->cl_stats    = args->stats ? : program->stats;
 404	clnt->cl_metrics  = rpc_alloc_iostats(clnt);
 405	rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
 406	err = -ENOMEM;
 407	if (clnt->cl_metrics == NULL)
 408		goto out_no_stats;
 409	clnt->cl_program  = program;
 410	INIT_LIST_HEAD(&clnt->cl_tasks);
 411	spin_lock_init(&clnt->cl_lock);
 412
 413	timeout = xprt->timeout;
 414	if (args->timeout != NULL) {
 415		memcpy(&clnt->cl_timeout_default, args->timeout,
 416				sizeof(clnt->cl_timeout_default));
 417		timeout = &clnt->cl_timeout_default;
 418	}
 419
 420	rpc_clnt_set_transport(clnt, xprt, timeout);
 421	xprt->main = true;
 422	xprt_iter_init(&clnt->cl_xpi, xps);
 423	xprt_switch_put(xps);
 424
 425	clnt->cl_rtt = &clnt->cl_rtt_default;
 426	rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
 427
 428	refcount_set(&clnt->cl_count, 1);
 429
 430	if (nodename == NULL)
 431		nodename = utsname()->nodename;
 432	/* save the nodename */
 433	rpc_clnt_set_nodename(clnt, nodename);
 434
 435	rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt));
 436	err = rpc_client_register(clnt, args->authflavor, args->client_name);
 437	if (err)
 438		goto out_no_path;
 439	if (parent)
 440		refcount_inc(&parent->cl_count);
 441
 442	trace_rpc_clnt_new(clnt, xprt, args);
 443	return clnt;
 444
 445out_no_path:
 446	rpc_free_iostats(clnt->cl_metrics);
 447out_no_stats:
 448	put_cred(clnt->cl_cred);
 449	rpc_free_clid(clnt);
 450out_no_clid:
 451	kfree(clnt);
 452out_err:
 453	rpciod_down();
 454out_no_rpciod:
 455	xprt_switch_put(xps);
 456	xprt_put(xprt);
 457	trace_rpc_clnt_new_err(program->name, args->servername, err);
 458	return ERR_PTR(err);
 459}
 460
 461static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
 462					struct rpc_xprt *xprt)
 463{
 464	struct rpc_clnt *clnt = NULL;
 465	struct rpc_xprt_switch *xps;
 466
 467	if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
 468		WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
 469		xps = args->bc_xprt->xpt_bc_xps;
 470		xprt_switch_get(xps);
 471	} else {
 472		xps = xprt_switch_alloc(xprt, GFP_KERNEL);
 473		if (xps == NULL) {
 474			xprt_put(xprt);
 475			return ERR_PTR(-ENOMEM);
 476		}
 477		if (xprt->bc_xprt) {
 478			xprt_switch_get(xps);
 479			xprt->bc_xprt->xpt_bc_xps = xps;
 480		}
 481	}
 482	clnt = rpc_new_client(args, xps, xprt, NULL);
 483	if (IS_ERR(clnt))
 484		return clnt;
 485
 486	if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
 487		int err = rpc_ping(clnt);
 488		if (err != 0) {
 489			rpc_shutdown_client(clnt);
 490			return ERR_PTR(err);
 491		}
 492	} else if (args->flags & RPC_CLNT_CREATE_CONNECTED) {
 493		int err = rpc_ping_noreply(clnt);
 494		if (err != 0) {
 495			rpc_shutdown_client(clnt);
 496			return ERR_PTR(err);
 497		}
 498	}
 499
 500	clnt->cl_softrtry = 1;
 501	if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
 502		clnt->cl_softrtry = 0;
 503		if (args->flags & RPC_CLNT_CREATE_SOFTERR)
 504			clnt->cl_softerr = 1;
 505	}
 506
 507	if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
 508		clnt->cl_autobind = 1;
 509	if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
 510		clnt->cl_noretranstimeo = 1;
 511	if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
 512		clnt->cl_discrtry = 1;
 513	if (!(args->flags & RPC_CLNT_CREATE_QUIET))
 514		clnt->cl_chatty = 1;
 515
 516	return clnt;
 517}
 518
 519/**
 520 * rpc_create - create an RPC client and transport with one call
 521 * @args: rpc_clnt create argument structure
 522 *
 523 * Creates and initializes an RPC transport and an RPC client.
 524 *
 525 * It can ping the server in order to determine if it is up, and to see if
 526 * it supports this program and version.  RPC_CLNT_CREATE_NOPING disables
 527 * this behavior so asynchronous tasks can also use rpc_create.
 528 */
 529struct rpc_clnt *rpc_create(struct rpc_create_args *args)
 530{
 531	struct rpc_xprt *xprt;
 532	struct xprt_create xprtargs = {
 533		.net = args->net,
 534		.ident = args->protocol,
 535		.srcaddr = args->saddress,
 536		.dstaddr = args->address,
 537		.addrlen = args->addrsize,
 538		.servername = args->servername,
 539		.bc_xprt = args->bc_xprt,
 540		.xprtsec = args->xprtsec,
 541		.connect_timeout = args->connect_timeout,
 542		.reconnect_timeout = args->reconnect_timeout,
 543	};
 544	char servername[RPC_MAXNETNAMELEN];
 545	struct rpc_clnt *clnt;
 546	int i;
 547
 548	if (args->bc_xprt) {
 549		WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
 550		xprt = args->bc_xprt->xpt_bc_xprt;
 551		if (xprt) {
 552			xprt_get(xprt);
 553			return rpc_create_xprt(args, xprt);
 554		}
 555	}
 556
 557	if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
 558		xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
 559	if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
 560		xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
 561	/*
 562	 * If the caller chooses not to specify a hostname, whip
 563	 * up a string representation of the passed-in address.
 564	 */
 565	if (xprtargs.servername == NULL) {
 566		struct sockaddr_un *sun =
 567				(struct sockaddr_un *)args->address;
 568		struct sockaddr_in *sin =
 569				(struct sockaddr_in *)args->address;
 570		struct sockaddr_in6 *sin6 =
 571				(struct sockaddr_in6 *)args->address;
 572
 573		servername[0] = '\0';
 574		switch (args->address->sa_family) {
 575		case AF_LOCAL:
 576			if (sun->sun_path[0])
 577				snprintf(servername, sizeof(servername), "%s",
 578					 sun->sun_path);
 579			else
 580				snprintf(servername, sizeof(servername), "@%s",
 581					 sun->sun_path+1);
 582			break;
 583		case AF_INET:
 584			snprintf(servername, sizeof(servername), "%pI4",
 585				 &sin->sin_addr.s_addr);
 586			break;
 587		case AF_INET6:
 588			snprintf(servername, sizeof(servername), "%pI6",
 589				 &sin6->sin6_addr);
 590			break;
 591		default:
 592			/* caller wants default server name, but
 593			 * address family isn't recognized. */
 594			return ERR_PTR(-EINVAL);
 595		}
 596		xprtargs.servername = servername;
 597	}
 598
 599	xprt = xprt_create_transport(&xprtargs);
 600	if (IS_ERR(xprt))
 601		return (struct rpc_clnt *)xprt;
 602
 603	/*
 604	 * By default, kernel RPC client connects from a reserved port.
 605	 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
 606	 * but it is always enabled for rpciod, which handles the connect
 607	 * operation.
 608	 */
 609	xprt->resvport = 1;
 610	if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
 611		xprt->resvport = 0;
 612	xprt->reuseport = 0;
 613	if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
 614		xprt->reuseport = 1;
 615
 616	clnt = rpc_create_xprt(args, xprt);
 617	if (IS_ERR(clnt) || args->nconnect <= 1)
 618		return clnt;
 619
 620	for (i = 0; i < args->nconnect - 1; i++) {
 621		if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
 622			break;
 623	}
 624	return clnt;
 625}
 626EXPORT_SYMBOL_GPL(rpc_create);
 627
 628/*
 629 * This function clones the RPC client structure. It allows us to share the
 630 * same transport while varying parameters such as the authentication
 631 * flavour.
 632 */
 633static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
 634					   struct rpc_clnt *clnt)
 635{
 636	struct rpc_xprt_switch *xps;
 637	struct rpc_xprt *xprt;
 638	struct rpc_clnt *new;
 639	int err;
 640
 641	err = -ENOMEM;
 642	rcu_read_lock();
 643	xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
 644	xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
 645	rcu_read_unlock();
 646	if (xprt == NULL || xps == NULL) {
 647		xprt_put(xprt);
 648		xprt_switch_put(xps);
 649		goto out_err;
 650	}
 651	args->servername = xprt->servername;
 652	args->nodename = clnt->cl_nodename;
 653
 654	new = rpc_new_client(args, xps, xprt, clnt);
 655	if (IS_ERR(new))
 656		return new;
 
 
 657
 658	/* Turn off autobind on clones */
 659	new->cl_autobind = 0;
 660	new->cl_softrtry = clnt->cl_softrtry;
 661	new->cl_softerr = clnt->cl_softerr;
 662	new->cl_noretranstimeo = clnt->cl_noretranstimeo;
 663	new->cl_discrtry = clnt->cl_discrtry;
 664	new->cl_chatty = clnt->cl_chatty;
 665	new->cl_principal = clnt->cl_principal;
 666	new->cl_max_connect = clnt->cl_max_connect;
 667	return new;
 668
 669out_err:
 670	trace_rpc_clnt_clone_err(clnt, err);
 671	return ERR_PTR(err);
 672}
 673
 674/**
 675 * rpc_clone_client - Clone an RPC client structure
 676 *
 677 * @clnt: RPC client whose parameters are copied
 678 *
 679 * Returns a fresh RPC client or an ERR_PTR.
 680 */
 681struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
 682{
 683	struct rpc_create_args args = {
 684		.program	= clnt->cl_program,
 685		.prognumber	= clnt->cl_prog,
 686		.version	= clnt->cl_vers,
 687		.authflavor	= clnt->cl_auth->au_flavor,
 688		.cred		= clnt->cl_cred,
 689		.stats		= clnt->cl_stats,
 690	};
 691	return __rpc_clone_client(&args, clnt);
 692}
 693EXPORT_SYMBOL_GPL(rpc_clone_client);
 694
 695/**
 696 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
 697 *
 698 * @clnt: RPC client whose parameters are copied
 699 * @flavor: security flavor for new client
 700 *
 701 * Returns a fresh RPC client or an ERR_PTR.
 702 */
 703struct rpc_clnt *
 704rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
 705{
 706	struct rpc_create_args args = {
 707		.program	= clnt->cl_program,
 708		.prognumber	= clnt->cl_prog,
 709		.version	= clnt->cl_vers,
 710		.authflavor	= flavor,
 711		.cred		= clnt->cl_cred,
 712		.stats		= clnt->cl_stats,
 713	};
 714	return __rpc_clone_client(&args, clnt);
 715}
 716EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
 717
 718/**
 719 * rpc_switch_client_transport: switch the RPC transport on the fly
 720 * @clnt: pointer to a struct rpc_clnt
 721 * @args: pointer to the new transport arguments
 722 * @timeout: pointer to the new timeout parameters
 723 *
 724 * This function allows the caller to switch the RPC transport for the
 725 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
 726 * server, for instance.  It assumes that the caller has ensured that
 727 * there are no active RPC tasks by using some form of locking.
 728 *
 729 * Returns zero if "clnt" is now using the new xprt.  Otherwise a
 730 * negative errno is returned, and "clnt" continues to use the old
 731 * xprt.
 732 */
 733int rpc_switch_client_transport(struct rpc_clnt *clnt,
 734		struct xprt_create *args,
 735		const struct rpc_timeout *timeout)
 736{
 737	const struct rpc_timeout *old_timeo;
 738	rpc_authflavor_t pseudoflavor;
 739	struct rpc_xprt_switch *xps, *oldxps;
 740	struct rpc_xprt *xprt, *old;
 741	struct rpc_clnt *parent;
 742	int err;
 743
 744	args->xprtsec = clnt->cl_xprtsec;
 745	xprt = xprt_create_transport(args);
 746	if (IS_ERR(xprt))
 
 
 747		return PTR_ERR(xprt);
 
 748
 749	xps = xprt_switch_alloc(xprt, GFP_KERNEL);
 750	if (xps == NULL) {
 751		xprt_put(xprt);
 752		return -ENOMEM;
 753	}
 754
 755	pseudoflavor = clnt->cl_auth->au_flavor;
 756
 757	old_timeo = clnt->cl_timeout;
 758	old = rpc_clnt_set_transport(clnt, xprt, timeout);
 759	oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
 760
 761	rpc_unregister_client(clnt);
 762	__rpc_clnt_remove_pipedir(clnt);
 763	rpc_sysfs_client_destroy(clnt);
 764	rpc_clnt_debugfs_unregister(clnt);
 765
 766	/*
 767	 * A new transport was created.  "clnt" therefore
 768	 * becomes the root of a new cl_parent tree.  clnt's
 769	 * children, if it has any, still point to the old xprt.
 770	 */
 771	parent = clnt->cl_parent;
 772	clnt->cl_parent = clnt;
 773
 774	/*
 775	 * The old rpc_auth cache cannot be re-used.  GSS
 776	 * contexts in particular are between a single
 777	 * client and server.
 778	 */
 779	err = rpc_client_register(clnt, pseudoflavor, NULL);
 780	if (err)
 781		goto out_revert;
 782
 783	synchronize_rcu();
 784	if (parent != clnt)
 785		rpc_release_client(parent);
 786	xprt_switch_put(oldxps);
 787	xprt_put(old);
 788	trace_rpc_clnt_replace_xprt(clnt);
 789	return 0;
 790
 791out_revert:
 792	xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
 793	rpc_clnt_set_transport(clnt, old, old_timeo);
 794	clnt->cl_parent = parent;
 795	rpc_client_register(clnt, pseudoflavor, NULL);
 796	xprt_switch_put(xps);
 797	xprt_put(xprt);
 798	trace_rpc_clnt_replace_xprt_err(clnt);
 799	return err;
 800}
 801EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
 802
 803static struct rpc_xprt_switch *rpc_clnt_xprt_switch_get(struct rpc_clnt *clnt)
 
 804{
 805	struct rpc_xprt_switch *xps;
 806
 807	rcu_read_lock();
 808	xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
 809	rcu_read_unlock();
 810
 811	return xps;
 812}
 813
 814static
 815int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi,
 816			     void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps))
 817{
 818	struct rpc_xprt_switch *xps;
 819
 820	xps = rpc_clnt_xprt_switch_get(clnt);
 821	if (xps == NULL)
 822		return -EAGAIN;
 823	func(xpi, xps);
 824	xprt_switch_put(xps);
 825	return 0;
 826}
 827
 828static
 829int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
 830{
 831	return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall);
 832}
 833
 834static
 835int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt,
 836				    struct rpc_xprt_iter *xpi)
 837{
 838	return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline);
 839}
 840
 841/**
 842 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
 843 * @clnt: pointer to client
 844 * @fn: function to apply
 845 * @data: void pointer to function data
 846 *
 847 * Iterates through the list of RPC transports currently attached to the
 848 * client and applies the function fn(clnt, xprt, data).
 849 *
 850 * On error, the iteration stops, and the function returns the error value.
 851 */
 852int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
 853		int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
 854		void *data)
 855{
 856	struct rpc_xprt_iter xpi;
 857	int ret;
 858
 859	ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
 860	if (ret)
 861		return ret;
 862	for (;;) {
 863		struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
 864
 865		if (!xprt)
 866			break;
 867		ret = fn(clnt, xprt, data);
 868		xprt_put(xprt);
 869		if (ret < 0)
 870			break;
 871	}
 872	xprt_iter_destroy(&xpi);
 873	return ret;
 874}
 875EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
 876
 877/*
 878 * Kill all tasks for the given client.
 879 * XXX: kill their descendants as well?
 880 */
 881void rpc_killall_tasks(struct rpc_clnt *clnt)
 882{
 883	struct rpc_task	*rovr;
 884
 885
 886	if (list_empty(&clnt->cl_tasks))
 887		return;
 888
 889	/*
 890	 * Spin lock all_tasks to prevent changes...
 891	 */
 892	trace_rpc_clnt_killall(clnt);
 893	spin_lock(&clnt->cl_lock);
 894	list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
 895		rpc_signal_task(rovr);
 896	spin_unlock(&clnt->cl_lock);
 897}
 898EXPORT_SYMBOL_GPL(rpc_killall_tasks);
 899
 900/**
 901 * rpc_cancel_tasks - try to cancel a set of RPC tasks
 902 * @clnt: Pointer to RPC client
 903 * @error: RPC task error value to set
 904 * @fnmatch: Pointer to selector function
 905 * @data: User data
 906 *
 907 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled.
 908 * The argument @error must be a negative error value.
 909 */
 910unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
 911			       bool (*fnmatch)(const struct rpc_task *,
 912					       const void *),
 913			       const void *data)
 914{
 915	struct rpc_task *task;
 916	unsigned long count = 0;
 917
 918	if (list_empty(&clnt->cl_tasks))
 919		return 0;
 920	/*
 921	 * Spin lock all_tasks to prevent changes...
 922	 */
 923	spin_lock(&clnt->cl_lock);
 924	list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
 925		if (!RPC_IS_ACTIVATED(task))
 926			continue;
 927		if (!fnmatch(task, data))
 928			continue;
 929		rpc_task_try_cancel(task, error);
 930		count++;
 931	}
 932	spin_unlock(&clnt->cl_lock);
 933	return count;
 934}
 935EXPORT_SYMBOL_GPL(rpc_cancel_tasks);
 936
 937static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt,
 938				    struct rpc_xprt *xprt, void *dummy)
 939{
 940	if (xprt_connected(xprt))
 941		xprt_force_disconnect(xprt);
 942	return 0;
 943}
 944
 945void rpc_clnt_disconnect(struct rpc_clnt *clnt)
 946{
 947	rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL);
 948}
 949EXPORT_SYMBOL_GPL(rpc_clnt_disconnect);
 950
 951/*
 952 * Properly shut down an RPC client, terminating all outstanding
 953 * requests.
 954 */
 955void rpc_shutdown_client(struct rpc_clnt *clnt)
 956{
 957	might_sleep();
 958
 959	trace_rpc_clnt_shutdown(clnt);
 
 
 960
 961	while (!list_empty(&clnt->cl_tasks)) {
 962		rpc_killall_tasks(clnt);
 963		wait_event_timeout(destroy_wait,
 964			list_empty(&clnt->cl_tasks), 1*HZ);
 965	}
 966
 967	rpc_release_client(clnt);
 968}
 969EXPORT_SYMBOL_GPL(rpc_shutdown_client);
 970
 971/*
 972 * Free an RPC client
 973 */
 974static void rpc_free_client_work(struct work_struct *work)
 975{
 976	struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
 977
 978	trace_rpc_clnt_free(clnt);
 979
 980	/* These might block on processes that might allocate memory,
 981	 * so they cannot be called in rpciod, so they are handled separately
 982	 * here.
 983	 */
 984	rpc_sysfs_client_destroy(clnt);
 985	rpc_clnt_debugfs_unregister(clnt);
 986	rpc_free_clid(clnt);
 987	rpc_clnt_remove_pipedir(clnt);
 988	xprt_put(rcu_dereference_raw(clnt->cl_xprt));
 989
 990	kfree(clnt);
 991	rpciod_down();
 992}
 993static struct rpc_clnt *
 994rpc_free_client(struct rpc_clnt *clnt)
 995{
 996	struct rpc_clnt *parent = NULL;
 997
 998	trace_rpc_clnt_release(clnt);
 
 
 999	if (clnt->cl_parent != clnt)
1000		parent = clnt->cl_parent;
 
 
1001	rpc_unregister_client(clnt);
1002	rpc_free_iostats(clnt->cl_metrics);
1003	clnt->cl_metrics = NULL;
 
1004	xprt_iter_destroy(&clnt->cl_xpi);
 
1005	put_cred(clnt->cl_cred);
1006
1007	INIT_WORK(&clnt->cl_work, rpc_free_client_work);
1008	schedule_work(&clnt->cl_work);
1009	return parent;
1010}
1011
1012/*
1013 * Free an RPC client
1014 */
1015static struct rpc_clnt *
1016rpc_free_auth(struct rpc_clnt *clnt)
1017{
 
 
 
1018	/*
1019	 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
1020	 *       release remaining GSS contexts. This mechanism ensures
1021	 *       that it can do so safely.
1022	 */
1023	if (clnt->cl_auth != NULL) {
1024		rpcauth_release(clnt->cl_auth);
1025		clnt->cl_auth = NULL;
1026	}
1027	if (refcount_dec_and_test(&clnt->cl_count))
1028		return rpc_free_client(clnt);
1029	return NULL;
1030}
1031
1032/*
1033 * Release reference to the RPC client
1034 */
1035void
1036rpc_release_client(struct rpc_clnt *clnt)
1037{
 
 
1038	do {
1039		if (list_empty(&clnt->cl_tasks))
1040			wake_up(&destroy_wait);
1041		if (refcount_dec_not_one(&clnt->cl_count))
1042			break;
1043		clnt = rpc_free_auth(clnt);
1044	} while (clnt != NULL);
1045}
1046EXPORT_SYMBOL_GPL(rpc_release_client);
1047
1048/**
1049 * rpc_bind_new_program - bind a new RPC program to an existing client
1050 * @old: old rpc_client
1051 * @program: rpc program to set
1052 * @vers: rpc program version
1053 *
1054 * Clones the rpc client and sets up a new RPC program. This is mainly
1055 * of use for enabling different RPC programs to share the same transport.
1056 * The Sun NFSv2/v3 ACL protocol can do this.
1057 */
1058struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
1059				      const struct rpc_program *program,
1060				      u32 vers)
1061{
1062	struct rpc_create_args args = {
1063		.program	= program,
1064		.prognumber	= program->number,
1065		.version	= vers,
1066		.authflavor	= old->cl_auth->au_flavor,
1067		.cred		= old->cl_cred,
1068		.stats		= old->cl_stats,
1069		.timeout	= old->cl_timeout,
1070	};
1071	struct rpc_clnt *clnt;
1072	int err;
1073
1074	clnt = __rpc_clone_client(&args, old);
1075	if (IS_ERR(clnt))
1076		goto out;
1077	err = rpc_ping(clnt);
1078	if (err != 0) {
1079		rpc_shutdown_client(clnt);
1080		clnt = ERR_PTR(err);
1081	}
1082out:
1083	return clnt;
1084}
1085EXPORT_SYMBOL_GPL(rpc_bind_new_program);
1086
1087struct rpc_xprt *
1088rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1089{
1090	struct rpc_xprt_switch *xps;
1091
1092	if (!xprt)
1093		return NULL;
1094	rcu_read_lock();
1095	xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1096	atomic_long_inc(&xps->xps_queuelen);
1097	rcu_read_unlock();
1098	atomic_long_inc(&xprt->queuelen);
1099
1100	return xprt;
1101}
1102
1103static void
1104rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1105{
1106	struct rpc_xprt_switch *xps;
1107
1108	atomic_long_dec(&xprt->queuelen);
1109	rcu_read_lock();
1110	xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1111	atomic_long_dec(&xps->xps_queuelen);
1112	rcu_read_unlock();
1113
1114	xprt_put(xprt);
1115}
1116
1117void rpc_task_release_transport(struct rpc_task *task)
1118{
1119	struct rpc_xprt *xprt = task->tk_xprt;
1120
1121	if (xprt) {
1122		task->tk_xprt = NULL;
1123		if (task->tk_client)
1124			rpc_task_release_xprt(task->tk_client, xprt);
1125		else
1126			xprt_put(xprt);
1127	}
1128}
1129EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1130
1131void rpc_task_release_client(struct rpc_task *task)
1132{
1133	struct rpc_clnt *clnt = task->tk_client;
1134
1135	rpc_task_release_transport(task);
1136	if (clnt != NULL) {
1137		/* Remove from client task list */
1138		spin_lock(&clnt->cl_lock);
1139		list_del(&task->tk_task);
1140		spin_unlock(&clnt->cl_lock);
1141		task->tk_client = NULL;
1142
1143		rpc_release_client(clnt);
1144	}
1145}
1146
1147static struct rpc_xprt *
1148rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1149{
1150	struct rpc_xprt *xprt;
1151
1152	rcu_read_lock();
1153	xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1154	rcu_read_unlock();
1155	return rpc_task_get_xprt(clnt, xprt);
1156}
1157
1158static struct rpc_xprt *
1159rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1160{
1161	return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1162}
1163
1164static
1165void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1166{
1167	if (task->tk_xprt) {
1168		if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) &&
1169		      (task->tk_flags & RPC_TASK_MOVEABLE)))
1170			return;
1171		xprt_release(task);
1172		xprt_put(task->tk_xprt);
1173	}
1174	if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1175		task->tk_xprt = rpc_task_get_first_xprt(clnt);
1176	else
1177		task->tk_xprt = rpc_task_get_next_xprt(clnt);
1178}
1179
1180static
1181void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1182{
1183	rpc_task_set_transport(task, clnt);
1184	task->tk_client = clnt;
1185	refcount_inc(&clnt->cl_count);
1186	if (clnt->cl_softrtry)
1187		task->tk_flags |= RPC_TASK_SOFT;
1188	if (clnt->cl_softerr)
1189		task->tk_flags |= RPC_TASK_TIMEOUT;
1190	if (clnt->cl_noretranstimeo)
1191		task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1192	/* Add to the client's list of all tasks */
1193	spin_lock(&clnt->cl_lock);
1194	list_add_tail(&task->tk_task, &clnt->cl_tasks);
1195	spin_unlock(&clnt->cl_lock);
 
 
 
 
 
1196}
1197
1198static void
1199rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1200{
1201	if (msg != NULL) {
1202		task->tk_msg.rpc_proc = msg->rpc_proc;
1203		task->tk_msg.rpc_argp = msg->rpc_argp;
1204		task->tk_msg.rpc_resp = msg->rpc_resp;
1205		task->tk_msg.rpc_cred = msg->rpc_cred;
1206		if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1207			get_cred(task->tk_msg.rpc_cred);
1208	}
1209}
1210
1211/*
1212 * Default callback for async RPC calls
1213 */
1214static void
1215rpc_default_callback(struct rpc_task *task, void *data)
1216{
1217}
1218
1219static const struct rpc_call_ops rpc_default_ops = {
1220	.rpc_call_done = rpc_default_callback,
1221};
1222
1223/**
1224 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1225 * @task_setup_data: pointer to task initialisation data
1226 */
1227struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1228{
1229	struct rpc_task *task;
1230
1231	task = rpc_new_task(task_setup_data);
1232	if (IS_ERR(task))
1233		return task;
1234
1235	if (!RPC_IS_ASYNC(task))
1236		task->tk_flags |= RPC_TASK_CRED_NOREF;
1237
1238	rpc_task_set_client(task, task_setup_data->rpc_client);
1239	rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1240
1241	if (task->tk_action == NULL)
1242		rpc_call_start(task);
1243
1244	atomic_inc(&task->tk_count);
1245	rpc_execute(task);
1246	return task;
1247}
1248EXPORT_SYMBOL_GPL(rpc_run_task);
1249
1250/**
1251 * rpc_call_sync - Perform a synchronous RPC call
1252 * @clnt: pointer to RPC client
1253 * @msg: RPC call parameters
1254 * @flags: RPC call flags
1255 */
1256int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1257{
1258	struct rpc_task	*task;
1259	struct rpc_task_setup task_setup_data = {
1260		.rpc_client = clnt,
1261		.rpc_message = msg,
1262		.callback_ops = &rpc_default_ops,
1263		.flags = flags,
1264	};
1265	int status;
1266
1267	WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1268	if (flags & RPC_TASK_ASYNC) {
1269		rpc_release_calldata(task_setup_data.callback_ops,
1270			task_setup_data.callback_data);
1271		return -EINVAL;
1272	}
1273
1274	task = rpc_run_task(&task_setup_data);
1275	if (IS_ERR(task))
1276		return PTR_ERR(task);
1277	status = task->tk_status;
1278	rpc_put_task(task);
1279	return status;
1280}
1281EXPORT_SYMBOL_GPL(rpc_call_sync);
1282
1283/**
1284 * rpc_call_async - Perform an asynchronous RPC call
1285 * @clnt: pointer to RPC client
1286 * @msg: RPC call parameters
1287 * @flags: RPC call flags
1288 * @tk_ops: RPC call ops
1289 * @data: user call data
1290 */
1291int
1292rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1293	       const struct rpc_call_ops *tk_ops, void *data)
1294{
1295	struct rpc_task	*task;
1296	struct rpc_task_setup task_setup_data = {
1297		.rpc_client = clnt,
1298		.rpc_message = msg,
1299		.callback_ops = tk_ops,
1300		.callback_data = data,
1301		.flags = flags|RPC_TASK_ASYNC,
1302	};
1303
1304	task = rpc_run_task(&task_setup_data);
1305	if (IS_ERR(task))
1306		return PTR_ERR(task);
1307	rpc_put_task(task);
1308	return 0;
1309}
1310EXPORT_SYMBOL_GPL(rpc_call_async);
1311
1312#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1313static void call_bc_encode(struct rpc_task *task);
1314
1315/**
1316 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1317 * rpc_execute against it
1318 * @req: RPC request
1319 * @timeout: timeout values to use for this task
1320 */
1321struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
1322		struct rpc_timeout *timeout)
1323{
1324	struct rpc_task *task;
1325	struct rpc_task_setup task_setup_data = {
1326		.callback_ops = &rpc_default_ops,
1327		.flags = RPC_TASK_SOFTCONN |
1328			RPC_TASK_NO_RETRANS_TIMEOUT,
1329	};
1330
1331	dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1332	/*
1333	 * Create an rpc_task to send the data
1334	 */
1335	task = rpc_new_task(&task_setup_data);
1336	if (IS_ERR(task)) {
1337		xprt_free_bc_request(req);
1338		return task;
1339	}
1340
1341	xprt_init_bc_request(req, task, timeout);
1342
1343	task->tk_action = call_bc_encode;
1344	atomic_inc(&task->tk_count);
1345	WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1346	rpc_execute(task);
1347
1348	dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1349	return task;
1350}
1351#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1352
1353/**
1354 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1355 * @req: RPC request to prepare
1356 * @pages: vector of struct page pointers
1357 * @base: offset in first page where receive should start, in bytes
1358 * @len: expected size of the upper layer data payload, in bytes
1359 * @hdrsize: expected size of upper layer reply header, in XDR words
1360 *
1361 */
1362void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1363			     unsigned int base, unsigned int len,
1364			     unsigned int hdrsize)
1365{
1366	hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
 
 
 
1367
1368	xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1369	trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1370}
1371EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1372
1373void
1374rpc_call_start(struct rpc_task *task)
1375{
1376	task->tk_action = call_start;
1377}
1378EXPORT_SYMBOL_GPL(rpc_call_start);
1379
1380/**
1381 * rpc_peeraddr - extract remote peer address from clnt's xprt
1382 * @clnt: RPC client structure
1383 * @buf: target buffer
1384 * @bufsize: length of target buffer
1385 *
1386 * Returns the number of bytes that are actually in the stored address.
1387 */
1388size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1389{
1390	size_t bytes;
1391	struct rpc_xprt *xprt;
1392
1393	rcu_read_lock();
1394	xprt = rcu_dereference(clnt->cl_xprt);
1395
1396	bytes = xprt->addrlen;
1397	if (bytes > bufsize)
1398		bytes = bufsize;
1399	memcpy(buf, &xprt->addr, bytes);
1400	rcu_read_unlock();
1401
1402	return bytes;
1403}
1404EXPORT_SYMBOL_GPL(rpc_peeraddr);
1405
1406/**
1407 * rpc_peeraddr2str - return remote peer address in printable format
1408 * @clnt: RPC client structure
1409 * @format: address format
1410 *
1411 * NB: the lifetime of the memory referenced by the returned pointer is
1412 * the same as the rpc_xprt itself.  As long as the caller uses this
1413 * pointer, it must hold the RCU read lock.
1414 */
1415const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1416			     enum rpc_display_format_t format)
1417{
1418	struct rpc_xprt *xprt;
1419
1420	xprt = rcu_dereference(clnt->cl_xprt);
1421
1422	if (xprt->address_strings[format] != NULL)
1423		return xprt->address_strings[format];
1424	else
1425		return "unprintable";
1426}
1427EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1428
1429static const struct sockaddr_in rpc_inaddr_loopback = {
1430	.sin_family		= AF_INET,
1431	.sin_addr.s_addr	= htonl(INADDR_ANY),
1432};
1433
1434static const struct sockaddr_in6 rpc_in6addr_loopback = {
1435	.sin6_family		= AF_INET6,
1436	.sin6_addr		= IN6ADDR_ANY_INIT,
1437};
1438
1439/*
1440 * Try a getsockname() on a connected datagram socket.  Using a
1441 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1442 * This conserves the ephemeral port number space.
1443 *
1444 * Returns zero and fills in "buf" if successful; otherwise, a
1445 * negative errno is returned.
1446 */
1447static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1448			struct sockaddr *buf)
1449{
1450	struct socket *sock;
1451	int err;
1452
1453	err = __sock_create(net, sap->sa_family,
1454				SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1455	if (err < 0) {
1456		dprintk("RPC:       can't create UDP socket (%d)\n", err);
1457		goto out;
1458	}
1459
1460	switch (sap->sa_family) {
1461	case AF_INET:
1462		err = kernel_bind(sock,
1463				(struct sockaddr *)&rpc_inaddr_loopback,
1464				sizeof(rpc_inaddr_loopback));
1465		break;
1466	case AF_INET6:
1467		err = kernel_bind(sock,
1468				(struct sockaddr *)&rpc_in6addr_loopback,
1469				sizeof(rpc_in6addr_loopback));
1470		break;
1471	default:
1472		err = -EAFNOSUPPORT;
1473		goto out_release;
1474	}
1475	if (err < 0) {
1476		dprintk("RPC:       can't bind UDP socket (%d)\n", err);
1477		goto out_release;
1478	}
1479
1480	err = kernel_connect(sock, sap, salen, 0);
1481	if (err < 0) {
1482		dprintk("RPC:       can't connect UDP socket (%d)\n", err);
1483		goto out_release;
1484	}
1485
1486	err = kernel_getsockname(sock, buf);
1487	if (err < 0) {
1488		dprintk("RPC:       getsockname failed (%d)\n", err);
1489		goto out_release;
1490	}
1491
1492	err = 0;
1493	if (buf->sa_family == AF_INET6) {
1494		struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1495		sin6->sin6_scope_id = 0;
1496	}
1497	dprintk("RPC:       %s succeeded\n", __func__);
1498
1499out_release:
1500	sock_release(sock);
1501out:
1502	return err;
1503}
1504
1505/*
1506 * Scraping a connected socket failed, so we don't have a useable
1507 * local address.  Fallback: generate an address that will prevent
1508 * the server from calling us back.
1509 *
1510 * Returns zero and fills in "buf" if successful; otherwise, a
1511 * negative errno is returned.
1512 */
1513static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1514{
1515	switch (family) {
1516	case AF_INET:
1517		if (buflen < sizeof(rpc_inaddr_loopback))
1518			return -EINVAL;
1519		memcpy(buf, &rpc_inaddr_loopback,
1520				sizeof(rpc_inaddr_loopback));
1521		break;
1522	case AF_INET6:
1523		if (buflen < sizeof(rpc_in6addr_loopback))
1524			return -EINVAL;
1525		memcpy(buf, &rpc_in6addr_loopback,
1526				sizeof(rpc_in6addr_loopback));
1527		break;
1528	default:
1529		dprintk("RPC:       %s: address family not supported\n",
1530			__func__);
1531		return -EAFNOSUPPORT;
1532	}
1533	dprintk("RPC:       %s: succeeded\n", __func__);
1534	return 0;
1535}
1536
1537/**
1538 * rpc_localaddr - discover local endpoint address for an RPC client
1539 * @clnt: RPC client structure
1540 * @buf: target buffer
1541 * @buflen: size of target buffer, in bytes
1542 *
1543 * Returns zero and fills in "buf" and "buflen" if successful;
1544 * otherwise, a negative errno is returned.
1545 *
1546 * This works even if the underlying transport is not currently connected,
1547 * or if the upper layer never previously provided a source address.
1548 *
1549 * The result of this function call is transient: multiple calls in
1550 * succession may give different results, depending on how local
1551 * networking configuration changes over time.
1552 */
1553int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1554{
1555	struct sockaddr_storage address;
1556	struct sockaddr *sap = (struct sockaddr *)&address;
1557	struct rpc_xprt *xprt;
1558	struct net *net;
1559	size_t salen;
1560	int err;
1561
1562	rcu_read_lock();
1563	xprt = rcu_dereference(clnt->cl_xprt);
1564	salen = xprt->addrlen;
1565	memcpy(sap, &xprt->addr, salen);
1566	net = get_net(xprt->xprt_net);
1567	rcu_read_unlock();
1568
1569	rpc_set_port(sap, 0);
1570	err = rpc_sockname(net, sap, salen, buf);
1571	put_net(net);
1572	if (err != 0)
1573		/* Couldn't discover local address, return ANYADDR */
1574		return rpc_anyaddr(sap->sa_family, buf, buflen);
1575	return 0;
1576}
1577EXPORT_SYMBOL_GPL(rpc_localaddr);
1578
1579void
1580rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1581{
1582	struct rpc_xprt *xprt;
1583
1584	rcu_read_lock();
1585	xprt = rcu_dereference(clnt->cl_xprt);
1586	if (xprt->ops->set_buffer_size)
1587		xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1588	rcu_read_unlock();
1589}
1590EXPORT_SYMBOL_GPL(rpc_setbufsize);
1591
1592/**
1593 * rpc_net_ns - Get the network namespace for this RPC client
1594 * @clnt: RPC client to query
1595 *
1596 */
1597struct net *rpc_net_ns(struct rpc_clnt *clnt)
1598{
1599	struct net *ret;
1600
1601	rcu_read_lock();
1602	ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1603	rcu_read_unlock();
1604	return ret;
1605}
1606EXPORT_SYMBOL_GPL(rpc_net_ns);
1607
1608/**
1609 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1610 * @clnt: RPC client to query
1611 *
1612 * For stream transports, this is one RPC record fragment (see RFC
1613 * 1831), as we don't support multi-record requests yet.  For datagram
1614 * transports, this is the size of an IP packet minus the IP, UDP, and
1615 * RPC header sizes.
1616 */
1617size_t rpc_max_payload(struct rpc_clnt *clnt)
1618{
1619	size_t ret;
1620
1621	rcu_read_lock();
1622	ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1623	rcu_read_unlock();
1624	return ret;
1625}
1626EXPORT_SYMBOL_GPL(rpc_max_payload);
1627
1628/**
1629 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1630 * @clnt: RPC client to query
1631 */
1632size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1633{
1634	struct rpc_xprt *xprt;
1635	size_t ret;
1636
1637	rcu_read_lock();
1638	xprt = rcu_dereference(clnt->cl_xprt);
1639	ret = xprt->ops->bc_maxpayload(xprt);
1640	rcu_read_unlock();
1641	return ret;
1642}
1643EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1644
1645unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1646{
1647	struct rpc_xprt *xprt;
1648	unsigned int ret;
1649
1650	rcu_read_lock();
1651	xprt = rcu_dereference(clnt->cl_xprt);
1652	ret = xprt->ops->bc_num_slots(xprt);
1653	rcu_read_unlock();
1654	return ret;
1655}
1656EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1657
1658/**
1659 * rpc_force_rebind - force transport to check that remote port is unchanged
1660 * @clnt: client to rebind
1661 *
1662 */
1663void rpc_force_rebind(struct rpc_clnt *clnt)
1664{
1665	if (clnt->cl_autobind) {
1666		rcu_read_lock();
1667		xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1668		rcu_read_unlock();
1669	}
1670}
1671EXPORT_SYMBOL_GPL(rpc_force_rebind);
1672
1673static int
1674__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1675{
1676	task->tk_status = 0;
1677	task->tk_rpc_status = 0;
1678	task->tk_action = action;
1679	return 1;
1680}
1681
1682/*
1683 * Restart an (async) RPC call. Usually called from within the
1684 * exit handler.
1685 */
1686int
1687rpc_restart_call(struct rpc_task *task)
1688{
1689	return __rpc_restart_call(task, call_start);
1690}
1691EXPORT_SYMBOL_GPL(rpc_restart_call);
1692
1693/*
1694 * Restart an (async) RPC call from the call_prepare state.
1695 * Usually called from within the exit handler.
1696 */
1697int
1698rpc_restart_call_prepare(struct rpc_task *task)
1699{
1700	if (task->tk_ops->rpc_call_prepare != NULL)
1701		return __rpc_restart_call(task, rpc_prepare_task);
1702	return rpc_restart_call(task);
1703}
1704EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1705
1706const char
1707*rpc_proc_name(const struct rpc_task *task)
1708{
1709	const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1710
1711	if (proc) {
1712		if (proc->p_name)
1713			return proc->p_name;
1714		else
1715			return "NULL";
1716	} else
1717		return "no proc";
1718}
1719
1720static void
1721__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1722{
1723	trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1724	rpc_task_set_rpc_status(task, rpc_status);
1725	rpc_exit(task, tk_status);
1726}
1727
1728static void
1729rpc_call_rpcerror(struct rpc_task *task, int status)
1730{
1731	__rpc_call_rpcerror(task, status, status);
1732}
1733
1734/*
1735 * 0.  Initial state
1736 *
1737 *     Other FSM states can be visited zero or more times, but
1738 *     this state is visited exactly once for each RPC.
1739 */
1740static void
1741call_start(struct rpc_task *task)
1742{
1743	struct rpc_clnt	*clnt = task->tk_client;
1744	int idx = task->tk_msg.rpc_proc->p_statidx;
1745
1746	trace_rpc_request(task);
1747
1748	if (task->tk_client->cl_shutdown) {
1749		rpc_call_rpcerror(task, -EIO);
1750		return;
1751	}
1752
1753	/* Increment call count (version might not be valid for ping) */
1754	if (clnt->cl_program->version[clnt->cl_vers])
1755		clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1756	clnt->cl_stats->rpccnt++;
1757	task->tk_action = call_reserve;
1758	rpc_task_set_transport(task, clnt);
1759}
1760
1761/*
1762 * 1.	Reserve an RPC call slot
1763 */
1764static void
1765call_reserve(struct rpc_task *task)
1766{
 
 
1767	task->tk_status  = 0;
1768	task->tk_action  = call_reserveresult;
1769	xprt_reserve(task);
1770}
1771
1772static void call_retry_reserve(struct rpc_task *task);
1773
1774/*
1775 * 1b.	Grok the result of xprt_reserve()
1776 */
1777static void
1778call_reserveresult(struct rpc_task *task)
1779{
1780	int status = task->tk_status;
1781
 
 
1782	/*
1783	 * After a call to xprt_reserve(), we must have either
1784	 * a request slot or else an error status.
1785	 */
1786	task->tk_status = 0;
1787	if (status >= 0) {
1788		if (task->tk_rqstp) {
1789			task->tk_action = call_refresh;
1790			return;
1791		}
1792
 
 
1793		rpc_call_rpcerror(task, -EIO);
1794		return;
1795	}
1796
 
 
 
 
 
 
 
 
 
 
1797	switch (status) {
1798	case -ENOMEM:
1799		rpc_delay(task, HZ >> 2);
1800		fallthrough;
1801	case -EAGAIN:	/* woken up; retry */
1802		task->tk_action = call_retry_reserve;
1803		return;
 
 
1804	default:
1805		rpc_call_rpcerror(task, status);
 
 
1806	}
 
1807}
1808
1809/*
1810 * 1c.	Retry reserving an RPC call slot
1811 */
1812static void
1813call_retry_reserve(struct rpc_task *task)
1814{
 
 
1815	task->tk_status  = 0;
1816	task->tk_action  = call_reserveresult;
1817	xprt_retry_reserve(task);
1818}
1819
1820/*
1821 * 2.	Bind and/or refresh the credentials
1822 */
1823static void
1824call_refresh(struct rpc_task *task)
1825{
 
 
1826	task->tk_action = call_refreshresult;
1827	task->tk_status = 0;
1828	task->tk_client->cl_stats->rpcauthrefresh++;
1829	rpcauth_refreshcred(task);
1830}
1831
1832/*
1833 * 2a.	Process the results of a credential refresh
1834 */
1835static void
1836call_refreshresult(struct rpc_task *task)
1837{
1838	int status = task->tk_status;
1839
 
 
1840	task->tk_status = 0;
1841	task->tk_action = call_refresh;
1842	switch (status) {
1843	case 0:
1844		if (rpcauth_uptodatecred(task)) {
1845			task->tk_action = call_allocate;
1846			return;
1847		}
1848		/* Use rate-limiting and a max number of retries if refresh
1849		 * had status 0 but failed to update the cred.
1850		 */
1851		fallthrough;
1852	case -ETIMEDOUT:
1853		rpc_delay(task, 3*HZ);
1854		fallthrough;
1855	case -EAGAIN:
1856		status = -EACCES;
1857		fallthrough;
1858	case -EKEYEXPIRED:
1859		if (!task->tk_cred_retry)
1860			break;
1861		task->tk_cred_retry--;
1862		trace_rpc_retry_refresh_status(task);
1863		return;
1864	case -ENOMEM:
1865		rpc_delay(task, HZ >> 4);
1866		return;
1867	}
1868	trace_rpc_refresh_status(task);
 
1869	rpc_call_rpcerror(task, status);
1870}
1871
1872/*
1873 * 2b.	Allocate the buffer. For details, see sched.c:rpc_malloc.
1874 *	(Note: buffer memory is freed in xprt_release).
1875 */
1876static void
1877call_allocate(struct rpc_task *task)
1878{
1879	const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1880	struct rpc_rqst *req = task->tk_rqstp;
1881	struct rpc_xprt *xprt = req->rq_xprt;
1882	const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1883	int status;
1884
 
 
1885	task->tk_status = 0;
1886	task->tk_action = call_encode;
1887
1888	if (req->rq_buffer)
1889		return;
1890
 
 
 
 
 
 
1891	/*
1892	 * Calculate the size (in quads) of the RPC call
1893	 * and reply headers, and convert both values
1894	 * to byte sizes.
1895	 */
1896	req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1897			   proc->p_arglen;
1898	req->rq_callsize <<= 2;
1899	/*
1900	 * Note: the reply buffer must at minimum allocate enough space
1901	 * for the 'struct accepted_reply' from RFC5531.
1902	 */
1903	req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1904			max_t(size_t, proc->p_replen, 2);
1905	req->rq_rcvsize <<= 2;
1906
1907	status = xprt->ops->buf_alloc(task);
1908	trace_rpc_buf_alloc(task, status);
1909	if (status == 0)
1910		return;
1911	if (status != -ENOMEM) {
1912		rpc_call_rpcerror(task, status);
1913		return;
1914	}
1915
 
 
1916	if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1917		task->tk_action = call_allocate;
1918		rpc_delay(task, HZ>>4);
1919		return;
1920	}
1921
1922	rpc_call_rpcerror(task, -ERESTARTSYS);
1923}
1924
1925static int
1926rpc_task_need_encode(struct rpc_task *task)
1927{
1928	return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1929		(!(task->tk_flags & RPC_TASK_SENT) ||
1930		 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1931		 xprt_request_need_retransmit(task));
1932}
1933
1934static void
1935rpc_xdr_encode(struct rpc_task *task)
1936{
1937	struct rpc_rqst	*req = task->tk_rqstp;
1938	struct xdr_stream xdr;
1939
1940	xdr_buf_init(&req->rq_snd_buf,
1941		     req->rq_buffer,
1942		     req->rq_callsize);
1943	xdr_buf_init(&req->rq_rcv_buf,
1944		     req->rq_rbuffer,
1945		     req->rq_rcvsize);
1946
1947	req->rq_reply_bytes_recvd = 0;
1948	req->rq_snd_buf.head[0].iov_len = 0;
1949	xdr_init_encode(&xdr, &req->rq_snd_buf,
1950			req->rq_snd_buf.head[0].iov_base, req);
 
1951	if (rpc_encode_header(task, &xdr))
1952		return;
1953
1954	task->tk_status = rpcauth_wrap_req(task, &xdr);
1955}
1956
1957/*
1958 * 3.	Encode arguments of an RPC call
1959 */
1960static void
1961call_encode(struct rpc_task *task)
1962{
1963	if (!rpc_task_need_encode(task))
1964		goto out;
1965
1966	/* Dequeue task from the receive queue while we're encoding */
1967	xprt_request_dequeue_xprt(task);
1968	/* Encode here so that rpcsec_gss can use correct sequence number. */
1969	rpc_xdr_encode(task);
1970	/* Add task to reply queue before transmission to avoid races */
1971	if (task->tk_status == 0 && rpc_reply_expected(task))
1972		task->tk_status = xprt_request_enqueue_receive(task);
1973	/* Did the encode result in an error condition? */
1974	if (task->tk_status != 0) {
1975		/* Was the error nonfatal? */
1976		switch (task->tk_status) {
1977		case -EAGAIN:
1978		case -ENOMEM:
1979			rpc_delay(task, HZ >> 4);
1980			break;
1981		case -EKEYEXPIRED:
1982			if (!task->tk_cred_retry) {
1983				rpc_call_rpcerror(task, task->tk_status);
1984			} else {
1985				task->tk_action = call_refresh;
1986				task->tk_cred_retry--;
1987				trace_rpc_retry_refresh_status(task);
 
1988			}
1989			break;
1990		default:
1991			rpc_call_rpcerror(task, task->tk_status);
1992		}
1993		return;
1994	}
1995
 
 
 
1996	xprt_request_enqueue_transmit(task);
1997out:
1998	task->tk_action = call_transmit;
1999	/* Check that the connection is OK */
2000	if (!xprt_bound(task->tk_xprt))
2001		task->tk_action = call_bind;
2002	else if (!xprt_connected(task->tk_xprt))
2003		task->tk_action = call_connect;
2004}
2005
2006/*
2007 * Helpers to check if the task was already transmitted, and
2008 * to take action when that is the case.
2009 */
2010static bool
2011rpc_task_transmitted(struct rpc_task *task)
2012{
2013	return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
2014}
2015
2016static void
2017rpc_task_handle_transmitted(struct rpc_task *task)
2018{
2019	xprt_end_transmit(task);
2020	task->tk_action = call_transmit_status;
2021}
2022
2023/*
2024 * 4.	Get the server port number if not yet set
2025 */
2026static void
2027call_bind(struct rpc_task *task)
2028{
2029	struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2030
2031	if (rpc_task_transmitted(task)) {
2032		rpc_task_handle_transmitted(task);
2033		return;
2034	}
2035
2036	if (xprt_bound(xprt)) {
2037		task->tk_action = call_connect;
2038		return;
2039	}
2040
 
 
2041	task->tk_action = call_bind_status;
2042	if (!xprt_prepare_transmit(task))
2043		return;
2044
2045	xprt->ops->rpcbind(task);
2046}
2047
2048/*
2049 * 4a.	Sort out bind result
2050 */
2051static void
2052call_bind_status(struct rpc_task *task)
2053{
2054	struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2055	int status = -EIO;
2056
2057	if (rpc_task_transmitted(task)) {
2058		rpc_task_handle_transmitted(task);
2059		return;
2060	}
2061
 
 
2062	if (task->tk_status >= 0)
2063		goto out_next;
2064	if (xprt_bound(xprt)) {
2065		task->tk_status = 0;
2066		goto out_next;
2067	}
2068
2069	switch (task->tk_status) {
2070	case -ENOMEM:
 
2071		rpc_delay(task, HZ >> 2);
2072		goto retry_timeout;
2073	case -EACCES:
2074		trace_rpcb_prog_unavail_err(task);
 
2075		/* fail immediately if this is an RPC ping */
2076		if (task->tk_msg.rpc_proc->p_proc == 0) {
2077			status = -EOPNOTSUPP;
2078			break;
2079		}
 
 
 
2080		rpc_delay(task, 3*HZ);
2081		goto retry_timeout;
2082	case -ENOBUFS:
2083		rpc_delay(task, HZ >> 2);
2084		goto retry_timeout;
2085	case -EAGAIN:
2086		goto retry_timeout;
2087	case -ETIMEDOUT:
2088		trace_rpcb_timeout_err(task);
 
2089		goto retry_timeout;
2090	case -EPFNOSUPPORT:
2091		/* server doesn't support any rpcbind version we know of */
2092		trace_rpcb_bind_version_err(task);
 
2093		break;
2094	case -EPROTONOSUPPORT:
2095		trace_rpcb_bind_version_err(task);
 
2096		goto retry_timeout;
2097	case -ECONNREFUSED:		/* connection problems */
2098	case -ECONNRESET:
2099	case -ECONNABORTED:
2100	case -ENOTCONN:
2101	case -EHOSTDOWN:
2102	case -ENETDOWN:
2103	case -EHOSTUNREACH:
2104	case -ENETUNREACH:
2105	case -EPIPE:
2106		trace_rpcb_unreachable_err(task);
 
2107		if (!RPC_IS_SOFTCONN(task)) {
2108			rpc_delay(task, 5*HZ);
2109			goto retry_timeout;
2110		}
2111		status = task->tk_status;
2112		break;
2113	default:
2114		trace_rpcb_unrecognized_err(task);
 
2115	}
2116
2117	rpc_call_rpcerror(task, status);
2118	return;
2119out_next:
2120	task->tk_action = call_connect;
2121	return;
2122retry_timeout:
2123	task->tk_status = 0;
2124	task->tk_action = call_bind;
2125	rpc_check_timeout(task);
2126}
2127
2128/*
2129 * 4b.	Connect to the RPC server
2130 */
2131static void
2132call_connect(struct rpc_task *task)
2133{
2134	struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2135
2136	if (rpc_task_transmitted(task)) {
2137		rpc_task_handle_transmitted(task);
2138		return;
2139	}
2140
2141	if (xprt_connected(xprt)) {
2142		task->tk_action = call_transmit;
2143		return;
2144	}
2145
 
 
 
 
2146	task->tk_action = call_connect_status;
2147	if (task->tk_status < 0)
2148		return;
2149	if (task->tk_flags & RPC_TASK_NOCONNECT) {
2150		rpc_call_rpcerror(task, -ENOTCONN);
2151		return;
2152	}
2153	if (!xprt_prepare_transmit(task))
2154		return;
2155	xprt_connect(task);
2156}
2157
2158/*
2159 * 4c.	Sort out connect result
2160 */
2161static void
2162call_connect_status(struct rpc_task *task)
2163{
2164	struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2165	struct rpc_clnt *clnt = task->tk_client;
2166	int status = task->tk_status;
2167
2168	if (rpc_task_transmitted(task)) {
2169		rpc_task_handle_transmitted(task);
2170		return;
2171	}
2172
 
2173	trace_rpc_connect_status(task);
2174
2175	if (task->tk_status == 0) {
2176		clnt->cl_stats->netreconn++;
2177		goto out_next;
2178	}
2179	if (xprt_connected(xprt)) {
2180		task->tk_status = 0;
2181		goto out_next;
2182	}
2183
2184	task->tk_status = 0;
2185	switch (status) {
2186	case -ECONNREFUSED:
2187	case -ECONNRESET:
2188		/* A positive refusal suggests a rebind is needed. */
2189		if (RPC_IS_SOFTCONN(task))
2190			break;
2191		if (clnt->cl_autobind) {
2192			rpc_force_rebind(clnt);
2193			goto out_retry;
2194		}
2195		fallthrough;
 
2196	case -ECONNABORTED:
2197	case -ENETDOWN:
2198	case -ENETUNREACH:
2199	case -EHOSTUNREACH:
2200	case -EPIPE:
2201	case -EPROTO:
2202		xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2203					    task->tk_rqstp->rq_connect_cookie);
2204		if (RPC_IS_SOFTCONN(task))
2205			break;
2206		/* retry with existing socket, after a delay */
2207		rpc_delay(task, 3*HZ);
2208		fallthrough;
2209	case -EADDRINUSE:
2210	case -ENOTCONN:
2211	case -EAGAIN:
2212	case -ETIMEDOUT:
2213		if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) &&
2214		    (task->tk_flags & RPC_TASK_MOVEABLE) &&
2215		    test_bit(XPRT_REMOVE, &xprt->state)) {
2216			struct rpc_xprt *saved = task->tk_xprt;
2217			struct rpc_xprt_switch *xps;
2218
2219			xps = rpc_clnt_xprt_switch_get(clnt);
2220			if (xps->xps_nxprts > 1) {
2221				long value;
2222
2223				xprt_release(task);
2224				value = atomic_long_dec_return(&xprt->queuelen);
2225				if (value == 0)
2226					rpc_xprt_switch_remove_xprt(xps, saved,
2227								    true);
2228				xprt_put(saved);
2229				task->tk_xprt = NULL;
2230				task->tk_action = call_start;
2231			}
2232			xprt_switch_put(xps);
2233			if (!task->tk_xprt)
2234				goto out;
2235		}
2236		goto out_retry;
2237	case -ENOBUFS:
2238		rpc_delay(task, HZ >> 2);
2239		goto out_retry;
2240	}
2241	rpc_call_rpcerror(task, status);
2242	return;
2243out_next:
2244	task->tk_action = call_transmit;
2245	return;
2246out_retry:
2247	/* Check for timeouts before looping back to call_bind */
2248	task->tk_action = call_bind;
2249out:
2250	rpc_check_timeout(task);
2251}
2252
2253/*
2254 * 5.	Transmit the RPC request, and wait for reply
2255 */
2256static void
2257call_transmit(struct rpc_task *task)
2258{
2259	if (rpc_task_transmitted(task)) {
2260		rpc_task_handle_transmitted(task);
2261		return;
2262	}
2263
 
 
2264	task->tk_action = call_transmit_status;
2265	if (!xprt_prepare_transmit(task))
2266		return;
2267	task->tk_status = 0;
2268	if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2269		if (!xprt_connected(task->tk_xprt)) {
2270			task->tk_status = -ENOTCONN;
2271			return;
2272		}
2273		xprt_transmit(task);
2274	}
2275	xprt_end_transmit(task);
2276}
2277
2278/*
2279 * 5a.	Handle cleanup after a transmission
2280 */
2281static void
2282call_transmit_status(struct rpc_task *task)
2283{
2284	task->tk_action = call_status;
2285
2286	/*
2287	 * Common case: success.  Force the compiler to put this
2288	 * test first.
2289	 */
2290	if (rpc_task_transmitted(task)) {
2291		task->tk_status = 0;
2292		xprt_request_wait_receive(task);
2293		return;
2294	}
2295
2296	switch (task->tk_status) {
2297	default:
 
2298		break;
2299	case -EBADMSG:
2300		task->tk_status = 0;
2301		task->tk_action = call_encode;
2302		break;
2303		/*
2304		 * Special cases: if we've been waiting on the
2305		 * socket's write_space() callback, or if the
2306		 * socket just returned a connection error,
2307		 * then hold onto the transport lock.
2308		 */
2309	case -ENOMEM:
2310	case -ENOBUFS:
2311		rpc_delay(task, HZ>>2);
2312		fallthrough;
2313	case -EBADSLT:
2314	case -EAGAIN:
2315		task->tk_action = call_transmit;
2316		task->tk_status = 0;
2317		break;
 
2318	case -EHOSTDOWN:
2319	case -ENETDOWN:
2320	case -EHOSTUNREACH:
2321	case -ENETUNREACH:
2322	case -EPERM:
2323		break;
2324	case -ECONNREFUSED:
2325		if (RPC_IS_SOFTCONN(task)) {
2326			if (!task->tk_msg.rpc_proc->p_proc)
2327				trace_xprt_ping(task->tk_xprt,
2328						task->tk_status);
2329			rpc_call_rpcerror(task, task->tk_status);
2330			return;
2331		}
2332		fallthrough;
2333	case -ECONNRESET:
2334	case -ECONNABORTED:
2335	case -EADDRINUSE:
2336	case -ENOTCONN:
2337	case -EPIPE:
2338		task->tk_action = call_bind;
2339		task->tk_status = 0;
2340		break;
2341	}
2342	rpc_check_timeout(task);
2343}
2344
2345#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2346static void call_bc_transmit(struct rpc_task *task);
2347static void call_bc_transmit_status(struct rpc_task *task);
2348
2349static void
2350call_bc_encode(struct rpc_task *task)
2351{
2352	xprt_request_enqueue_transmit(task);
2353	task->tk_action = call_bc_transmit;
2354}
2355
2356/*
2357 * 5b.	Send the backchannel RPC reply.  On error, drop the reply.  In
2358 * addition, disconnect on connectivity errors.
2359 */
2360static void
2361call_bc_transmit(struct rpc_task *task)
2362{
2363	task->tk_action = call_bc_transmit_status;
2364	if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2365		if (!xprt_prepare_transmit(task))
2366			return;
2367		task->tk_status = 0;
2368		xprt_transmit(task);
2369	}
2370	xprt_end_transmit(task);
2371}
2372
2373static void
2374call_bc_transmit_status(struct rpc_task *task)
2375{
2376	struct rpc_rqst *req = task->tk_rqstp;
2377
2378	if (rpc_task_transmitted(task))
2379		task->tk_status = 0;
2380
 
 
2381	switch (task->tk_status) {
2382	case 0:
2383		/* Success */
2384	case -ENETDOWN:
2385	case -EHOSTDOWN:
2386	case -EHOSTUNREACH:
2387	case -ENETUNREACH:
2388	case -ECONNRESET:
2389	case -ECONNREFUSED:
2390	case -EADDRINUSE:
2391	case -ENOTCONN:
2392	case -EPIPE:
2393		break;
2394	case -ENOMEM:
2395	case -ENOBUFS:
2396		rpc_delay(task, HZ>>2);
2397		fallthrough;
2398	case -EBADSLT:
2399	case -EAGAIN:
2400		task->tk_status = 0;
2401		task->tk_action = call_bc_transmit;
2402		return;
2403	case -ETIMEDOUT:
2404		/*
2405		 * Problem reaching the server.  Disconnect and let the
2406		 * forechannel reestablish the connection.  The server will
2407		 * have to retransmit the backchannel request and we'll
2408		 * reprocess it.  Since these ops are idempotent, there's no
2409		 * need to cache our reply at this time.
2410		 */
2411		printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2412			"error: %d\n", task->tk_status);
2413		xprt_conditional_disconnect(req->rq_xprt,
2414			req->rq_connect_cookie);
2415		break;
2416	default:
2417		/*
2418		 * We were unable to reply and will have to drop the
2419		 * request.  The server should reconnect and retransmit.
2420		 */
2421		printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2422			"error: %d\n", task->tk_status);
2423		break;
2424	}
2425	task->tk_action = rpc_exit_task;
2426}
2427#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2428
2429/*
2430 * 6.	Sort out the RPC call status
2431 */
2432static void
2433call_status(struct rpc_task *task)
2434{
2435	struct rpc_clnt	*clnt = task->tk_client;
2436	int		status;
2437
2438	if (!task->tk_msg.rpc_proc->p_proc)
2439		trace_xprt_ping(task->tk_xprt, task->tk_status);
2440
 
 
2441	status = task->tk_status;
2442	if (status >= 0) {
2443		task->tk_action = call_decode;
2444		return;
2445	}
2446
2447	trace_rpc_call_status(task);
2448	task->tk_status = 0;
2449	switch(status) {
2450	case -EHOSTDOWN:
2451	case -ENETDOWN:
2452	case -EHOSTUNREACH:
2453	case -ENETUNREACH:
2454	case -EPERM:
2455		if (RPC_IS_SOFTCONN(task))
2456			goto out_exit;
2457		/*
2458		 * Delay any retries for 3 seconds, then handle as if it
2459		 * were a timeout.
2460		 */
2461		rpc_delay(task, 3*HZ);
2462		fallthrough;
2463	case -ETIMEDOUT:
2464		break;
2465	case -ECONNREFUSED:
2466	case -ECONNRESET:
2467	case -ECONNABORTED:
2468	case -ENOTCONN:
2469		rpc_force_rebind(clnt);
2470		break;
2471	case -EADDRINUSE:
2472		rpc_delay(task, 3*HZ);
2473		fallthrough;
2474	case -EPIPE:
2475	case -EAGAIN:
2476		break;
2477	case -ENFILE:
2478	case -ENOBUFS:
2479	case -ENOMEM:
2480		rpc_delay(task, HZ>>2);
2481		break;
2482	case -EIO:
2483		/* shutdown or soft timeout */
2484		goto out_exit;
2485	default:
2486		if (clnt->cl_chatty)
2487			printk("%s: RPC call returned error %d\n",
2488			       clnt->cl_program->name, -status);
2489		goto out_exit;
2490	}
2491	task->tk_action = call_encode;
2492	rpc_check_timeout(task);
2493	return;
2494out_exit:
2495	rpc_call_rpcerror(task, status);
2496}
2497
2498static bool
2499rpc_check_connected(const struct rpc_rqst *req)
2500{
2501	/* No allocated request or transport? return true */
2502	if (!req || !req->rq_xprt)
2503		return true;
2504	return xprt_connected(req->rq_xprt);
2505}
2506
2507static void
2508rpc_check_timeout(struct rpc_task *task)
2509{
2510	struct rpc_clnt	*clnt = task->tk_client;
2511
2512	if (RPC_SIGNALLED(task))
2513		return;
2514
2515	if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2516		return;
2517
2518	trace_rpc_timeout_status(task);
2519	task->tk_timeouts++;
2520
2521	if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2522		rpc_call_rpcerror(task, -ETIMEDOUT);
2523		return;
2524	}
2525
2526	if (RPC_IS_SOFT(task)) {
2527		/*
2528		 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2529		 * been sent, it should time out only if the transport
2530		 * connection gets terminally broken.
2531		 */
2532		if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2533		    rpc_check_connected(task->tk_rqstp))
2534			return;
2535
2536		if (clnt->cl_chatty) {
2537			pr_notice_ratelimited(
2538				"%s: server %s not responding, timed out\n",
2539				clnt->cl_program->name,
2540				task->tk_xprt->servername);
2541		}
2542		if (task->tk_flags & RPC_TASK_TIMEOUT)
2543			rpc_call_rpcerror(task, -ETIMEDOUT);
2544		else
2545			__rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2546		return;
2547	}
2548
2549	if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2550		task->tk_flags |= RPC_CALL_MAJORSEEN;
2551		if (clnt->cl_chatty) {
2552			pr_notice_ratelimited(
2553				"%s: server %s not responding, still trying\n",
2554				clnt->cl_program->name,
2555				task->tk_xprt->servername);
2556		}
2557	}
2558	rpc_force_rebind(clnt);
2559	/*
2560	 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2561	 * event? RFC2203 requires the server to drop all such requests.
2562	 */
2563	rpcauth_invalcred(task);
2564}
2565
2566/*
2567 * 7.	Decode the RPC reply
2568 */
2569static void
2570call_decode(struct rpc_task *task)
2571{
2572	struct rpc_clnt	*clnt = task->tk_client;
2573	struct rpc_rqst	*req = task->tk_rqstp;
2574	struct xdr_stream xdr;
2575	int err;
2576
 
 
2577	if (!task->tk_msg.rpc_proc->p_decode) {
2578		task->tk_action = rpc_exit_task;
2579		return;
2580	}
2581
2582	if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2583		if (clnt->cl_chatty) {
2584			pr_notice_ratelimited("%s: server %s OK\n",
2585				clnt->cl_program->name,
2586				task->tk_xprt->servername);
2587		}
2588		task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2589	}
2590
2591	/*
 
 
 
 
 
 
2592	 * Did we ever call xprt_complete_rqst()? If not, we should assume
2593	 * the message is incomplete.
2594	 */
2595	err = -EAGAIN;
2596	if (!req->rq_reply_bytes_recvd)
2597		goto out;
2598
2599	/* Ensure that we see all writes made by xprt_complete_rqst()
2600	 * before it changed req->rq_reply_bytes_recvd.
2601	 */
2602	smp_rmb();
2603
2604	req->rq_rcv_buf.len = req->rq_private_buf.len;
2605	trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2606
2607	/* Check that the softirq receive buffer is valid */
2608	WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2609				sizeof(req->rq_rcv_buf)) != 0);
2610
2611	xdr_init_decode(&xdr, &req->rq_rcv_buf,
2612			req->rq_rcv_buf.head[0].iov_base, req);
2613	err = rpc_decode_header(task, &xdr);
2614out:
2615	switch (err) {
2616	case 0:
2617		task->tk_action = rpc_exit_task;
2618		task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2619		xdr_finish_decode(&xdr);
 
2620		return;
2621	case -EAGAIN:
2622		task->tk_status = 0;
2623		if (task->tk_client->cl_discrtry)
2624			xprt_conditional_disconnect(req->rq_xprt,
2625						    req->rq_connect_cookie);
2626		task->tk_action = call_encode;
2627		rpc_check_timeout(task);
2628		break;
2629	case -EKEYREJECTED:
2630		task->tk_action = call_reserve;
2631		rpc_check_timeout(task);
2632		rpcauth_invalcred(task);
2633		/* Ensure we obtain a new XID if we retry! */
2634		xprt_release(task);
2635	}
2636}
2637
2638static int
2639rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2640{
2641	struct rpc_clnt *clnt = task->tk_client;
2642	struct rpc_rqst	*req = task->tk_rqstp;
2643	__be32 *p;
2644	int error;
2645
2646	error = -EMSGSIZE;
2647	p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2648	if (!p)
2649		goto out_fail;
2650	*p++ = req->rq_xid;
2651	*p++ = rpc_call;
2652	*p++ = cpu_to_be32(RPC_VERSION);
2653	*p++ = cpu_to_be32(clnt->cl_prog);
2654	*p++ = cpu_to_be32(clnt->cl_vers);
2655	*p   = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2656
2657	error = rpcauth_marshcred(task, xdr);
2658	if (error < 0)
2659		goto out_fail;
2660	return 0;
2661out_fail:
2662	trace_rpc_bad_callhdr(task);
2663	rpc_call_rpcerror(task, error);
2664	return error;
2665}
2666
2667static noinline int
2668rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2669{
2670	struct rpc_clnt *clnt = task->tk_client;
2671	int error;
2672	__be32 *p;
2673
2674	/* RFC-1014 says that the representation of XDR data must be a
2675	 * multiple of four bytes
2676	 * - if it isn't pointer subtraction in the NFS client may give
2677	 *   undefined results
2678	 */
2679	if (task->tk_rqstp->rq_rcv_buf.len & 3)
2680		goto out_unparsable;
2681
2682	p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2683	if (!p)
2684		goto out_unparsable;
2685	p++;	/* skip XID */
2686	if (*p++ != rpc_reply)
2687		goto out_unparsable;
2688	if (*p++ != rpc_msg_accepted)
2689		goto out_msg_denied;
2690
2691	error = rpcauth_checkverf(task, xdr);
2692	if (error) {
2693		struct rpc_cred *cred = task->tk_rqstp->rq_cred;
2694
2695		if (!test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) {
2696			rpcauth_invalcred(task);
2697			if (!task->tk_cred_retry)
2698				goto out_err;
2699			task->tk_cred_retry--;
2700			trace_rpc__stale_creds(task);
2701			return -EKEYREJECTED;
2702		}
2703		goto out_verifier;
2704	}
2705
2706	p = xdr_inline_decode(xdr, sizeof(*p));
2707	if (!p)
2708		goto out_unparsable;
2709	switch (*p) {
2710	case rpc_success:
2711		return 0;
2712	case rpc_prog_unavail:
2713		trace_rpc__prog_unavail(task);
2714		error = -EPFNOSUPPORT;
2715		goto out_err;
2716	case rpc_prog_mismatch:
2717		trace_rpc__prog_mismatch(task);
2718		error = -EPROTONOSUPPORT;
2719		goto out_err;
2720	case rpc_proc_unavail:
2721		trace_rpc__proc_unavail(task);
2722		error = -EOPNOTSUPP;
2723		goto out_err;
2724	case rpc_garbage_args:
2725	case rpc_system_err:
2726		trace_rpc__garbage_args(task);
2727		error = -EIO;
2728		break;
2729	default:
2730		goto out_unparsable;
2731	}
2732
2733out_garbage:
2734	clnt->cl_stats->rpcgarbage++;
2735	if (task->tk_garb_retry) {
2736		task->tk_garb_retry--;
2737		task->tk_action = call_encode;
2738		return -EAGAIN;
2739	}
2740out_err:
2741	rpc_call_rpcerror(task, error);
2742	return error;
2743
2744out_unparsable:
2745	trace_rpc__unparsable(task);
2746	error = -EIO;
2747	goto out_garbage;
2748
2749out_verifier:
2750	trace_rpc_bad_verifier(task);
2751	switch (error) {
2752	case -EPROTONOSUPPORT:
2753		goto out_err;
2754	case -EACCES:
2755		/* Re-encode with a fresh cred */
2756		fallthrough;
2757	default:
2758		goto out_garbage;
2759	}
2760
2761out_msg_denied:
2762	error = -EACCES;
2763	p = xdr_inline_decode(xdr, sizeof(*p));
2764	if (!p)
2765		goto out_unparsable;
2766	switch (*p++) {
2767	case rpc_auth_error:
2768		break;
2769	case rpc_mismatch:
2770		trace_rpc__mismatch(task);
2771		error = -EPROTONOSUPPORT;
2772		goto out_err;
2773	default:
2774		goto out_unparsable;
2775	}
2776
2777	p = xdr_inline_decode(xdr, sizeof(*p));
2778	if (!p)
2779		goto out_unparsable;
2780	switch (*p++) {
2781	case rpc_autherr_rejectedcred:
2782	case rpc_autherr_rejectedverf:
2783	case rpcsec_gsserr_credproblem:
2784	case rpcsec_gsserr_ctxproblem:
2785		rpcauth_invalcred(task);
2786		if (!task->tk_cred_retry)
2787			break;
2788		task->tk_cred_retry--;
2789		trace_rpc__stale_creds(task);
2790		return -EKEYREJECTED;
2791	case rpc_autherr_badcred:
2792	case rpc_autherr_badverf:
2793		/* possibly garbled cred/verf? */
2794		if (!task->tk_garb_retry)
2795			break;
2796		task->tk_garb_retry--;
2797		trace_rpc__bad_creds(task);
2798		task->tk_action = call_encode;
2799		return -EAGAIN;
2800	case rpc_autherr_tooweak:
2801		trace_rpc__auth_tooweak(task);
2802		pr_warn("RPC: server %s requires stronger authentication.\n",
2803			task->tk_xprt->servername);
2804		break;
2805	default:
2806		goto out_unparsable;
2807	}
2808	goto out_err;
2809}
2810
2811static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2812		const void *obj)
2813{
2814}
2815
2816static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2817		void *obj)
2818{
2819	return 0;
2820}
2821
2822static const struct rpc_procinfo rpcproc_null = {
2823	.p_encode = rpcproc_encode_null,
2824	.p_decode = rpcproc_decode_null,
2825};
2826
2827static const struct rpc_procinfo rpcproc_null_noreply = {
2828	.p_encode = rpcproc_encode_null,
2829};
2830
2831static void
2832rpc_null_call_prepare(struct rpc_task *task, void *data)
2833{
2834	task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT;
2835	rpc_call_start(task);
 
 
 
 
 
2836}
2837
2838static const struct rpc_call_ops rpc_null_ops = {
2839	.rpc_call_prepare = rpc_null_call_prepare,
2840	.rpc_call_done = rpc_default_callback,
2841};
2842
2843static
2844struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2845		struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2846		const struct rpc_call_ops *ops, void *data)
2847{
2848	struct rpc_message msg = {
2849		.rpc_proc = &rpcproc_null,
2850	};
2851	struct rpc_task_setup task_setup_data = {
2852		.rpc_client = clnt,
2853		.rpc_xprt = xprt,
2854		.rpc_message = &msg,
2855		.rpc_op_cred = cred,
2856		.callback_ops = ops ?: &rpc_null_ops,
2857		.callback_data = data,
2858		.flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2859			 RPC_TASK_NULLCREDS,
2860	};
2861
2862	return rpc_run_task(&task_setup_data);
2863}
2864
2865struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2866{
2867	return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2868}
2869EXPORT_SYMBOL_GPL(rpc_call_null);
2870
2871static int rpc_ping(struct rpc_clnt *clnt)
2872{
2873	struct rpc_task	*task;
2874	int status;
2875
2876	if (clnt->cl_auth->au_ops->ping)
2877		return clnt->cl_auth->au_ops->ping(clnt);
2878
2879	task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL);
2880	if (IS_ERR(task))
2881		return PTR_ERR(task);
2882	status = task->tk_status;
2883	rpc_put_task(task);
2884	return status;
2885}
2886
2887static int rpc_ping_noreply(struct rpc_clnt *clnt)
2888{
2889	struct rpc_message msg = {
2890		.rpc_proc = &rpcproc_null_noreply,
2891	};
2892	struct rpc_task_setup task_setup_data = {
2893		.rpc_client = clnt,
2894		.rpc_message = &msg,
2895		.callback_ops = &rpc_null_ops,
2896		.flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2897	};
2898	struct rpc_task	*task;
2899	int status;
2900
2901	task = rpc_run_task(&task_setup_data);
2902	if (IS_ERR(task))
2903		return PTR_ERR(task);
2904	status = task->tk_status;
2905	rpc_put_task(task);
2906	return status;
2907}
2908
2909struct rpc_cb_add_xprt_calldata {
2910	struct rpc_xprt_switch *xps;
2911	struct rpc_xprt *xprt;
2912};
2913
2914static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2915{
2916	struct rpc_cb_add_xprt_calldata *data = calldata;
2917
2918	if (task->tk_status == 0)
2919		rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2920}
2921
2922static void rpc_cb_add_xprt_release(void *calldata)
2923{
2924	struct rpc_cb_add_xprt_calldata *data = calldata;
2925
2926	xprt_put(data->xprt);
2927	xprt_switch_put(data->xps);
2928	kfree(data);
2929}
2930
2931static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2932	.rpc_call_prepare = rpc_null_call_prepare,
2933	.rpc_call_done = rpc_cb_add_xprt_done,
2934	.rpc_release = rpc_cb_add_xprt_release,
2935};
2936
2937/**
2938 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2939 * @clnt: pointer to struct rpc_clnt
2940 * @xps: pointer to struct rpc_xprt_switch,
2941 * @xprt: pointer struct rpc_xprt
2942 * @in_max_connect: pointer to the max_connect value for the passed in xprt transport
2943 */
2944int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2945		struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2946		void *in_max_connect)
2947{
2948	struct rpc_cb_add_xprt_calldata *data;
2949	struct rpc_task *task;
2950	int max_connect = clnt->cl_max_connect;
2951
2952	if (in_max_connect)
2953		max_connect = *(int *)in_max_connect;
2954	if (xps->xps_nunique_destaddr_xprts + 1 > max_connect) {
2955		rcu_read_lock();
2956		pr_warn("SUNRPC: reached max allowed number (%d) did not add "
2957			"transport to server: %s\n", max_connect,
2958			rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
2959		rcu_read_unlock();
2960		return -EINVAL;
2961	}
2962
2963	data = kmalloc(sizeof(*data), GFP_KERNEL);
2964	if (!data)
2965		return -ENOMEM;
2966	data->xps = xprt_switch_get(xps);
2967	data->xprt = xprt_get(xprt);
2968	if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2969		rpc_cb_add_xprt_release(data);
2970		goto success;
2971	}
2972
2973	task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
 
2974			&rpc_cb_add_xprt_call_ops, data);
2975	if (IS_ERR(task))
2976		return PTR_ERR(task);
2977
2978	data->xps->xps_nunique_destaddr_xprts++;
2979	rpc_put_task(task);
2980success:
2981	return 1;
2982}
2983EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2984
2985static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt,
2986				    struct rpc_xprt *xprt,
2987				    struct rpc_add_xprt_test *data)
2988{
2989	struct rpc_task *task;
2990	int status = -EADDRINUSE;
2991
2992	/* Test the connection */
2993	task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2994	if (IS_ERR(task))
2995		return PTR_ERR(task);
2996
2997	status = task->tk_status;
2998	rpc_put_task(task);
2999
3000	if (status < 0)
3001		return status;
3002
3003	/* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
3004	data->add_xprt_test(clnt, xprt, data->data);
3005
3006	return 0;
3007}
3008
3009/**
3010 * rpc_clnt_setup_test_and_add_xprt()
3011 *
3012 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
3013 *   1) caller of the test function must dereference the rpc_xprt_switch
3014 *   and the rpc_xprt.
3015 *   2) test function must call rpc_xprt_switch_add_xprt, usually in
3016 *   the rpc_call_done routine.
3017 *
3018 * Upon success (return of 1), the test function adds the new
3019 * transport to the rpc_clnt xprt switch
3020 *
3021 * @clnt: struct rpc_clnt to get the new transport
3022 * @xps:  the rpc_xprt_switch to hold the new transport
3023 * @xprt: the rpc_xprt to test
3024 * @data: a struct rpc_add_xprt_test pointer that holds the test function
3025 *        and test function call data
3026 */
3027int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
3028				     struct rpc_xprt_switch *xps,
3029				     struct rpc_xprt *xprt,
3030				     void *data)
3031{
 
 
3032	int status = -EADDRINUSE;
3033
3034	xprt = xprt_get(xprt);
3035	xprt_switch_get(xps);
3036
3037	if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
3038		goto out_err;
3039
3040	status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
 
 
 
 
 
 
 
 
 
 
3041	if (status < 0)
3042		goto out_err;
3043
3044	status = 1;
 
 
 
 
 
 
 
3045out_err:
3046	xprt_put(xprt);
3047	xprt_switch_put(xps);
3048	if (status < 0)
3049		pr_info("RPC:   rpc_clnt_test_xprt failed: %d addr %s not "
3050			"added\n", status,
3051			xprt->address_strings[RPC_DISPLAY_ADDR]);
3052	/* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
3053	return status;
3054}
3055EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
3056
3057/**
3058 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
3059 * @clnt: pointer to struct rpc_clnt
3060 * @xprtargs: pointer to struct xprt_create
3061 * @setup: callback to test and/or set up the connection
3062 * @data: pointer to setup function data
3063 *
3064 * Creates a new transport using the parameters set in args and
3065 * adds it to clnt.
3066 * If ping is set, then test that connectivity succeeds before
3067 * adding the new transport.
3068 *
3069 */
3070int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
3071		struct xprt_create *xprtargs,
3072		int (*setup)(struct rpc_clnt *,
3073			struct rpc_xprt_switch *,
3074			struct rpc_xprt *,
3075			void *),
3076		void *data)
3077{
3078	struct rpc_xprt_switch *xps;
3079	struct rpc_xprt *xprt;
3080	unsigned long connect_timeout;
3081	unsigned long reconnect_timeout;
3082	unsigned char resvport, reuseport;
3083	int ret = 0, ident;
3084
3085	rcu_read_lock();
3086	xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3087	xprt = xprt_iter_xprt(&clnt->cl_xpi);
3088	if (xps == NULL || xprt == NULL) {
3089		rcu_read_unlock();
3090		xprt_switch_put(xps);
3091		return -EAGAIN;
3092	}
3093	resvport = xprt->resvport;
3094	reuseport = xprt->reuseport;
3095	connect_timeout = xprt->connect_timeout;
3096	reconnect_timeout = xprt->max_reconnect_timeout;
3097	ident = xprt->xprt_class->ident;
3098	rcu_read_unlock();
3099
3100	if (!xprtargs->ident)
3101		xprtargs->ident = ident;
3102	xprtargs->xprtsec = clnt->cl_xprtsec;
3103	xprt = xprt_create_transport(xprtargs);
3104	if (IS_ERR(xprt)) {
3105		ret = PTR_ERR(xprt);
3106		goto out_put_switch;
3107	}
3108	xprt->resvport = resvport;
3109	xprt->reuseport = reuseport;
3110
3111	if (xprtargs->connect_timeout)
3112		connect_timeout = xprtargs->connect_timeout;
3113	if (xprtargs->reconnect_timeout)
3114		reconnect_timeout = xprtargs->reconnect_timeout;
3115	if (xprt->ops->set_connect_timeout != NULL)
3116		xprt->ops->set_connect_timeout(xprt,
3117				connect_timeout,
3118				reconnect_timeout);
3119
3120	rpc_xprt_switch_set_roundrobin(xps);
3121	if (setup) {
3122		ret = setup(clnt, xps, xprt, data);
3123		if (ret != 0)
3124			goto out_put_xprt;
3125	}
3126	rpc_xprt_switch_add_xprt(xps, xprt);
3127out_put_xprt:
3128	xprt_put(xprt);
3129out_put_switch:
3130	xprt_switch_put(xps);
3131	return ret;
3132}
3133EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
3134
3135static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt,
3136				  struct rpc_xprt *xprt,
3137				  struct rpc_add_xprt_test *data)
3138{
3139	struct rpc_xprt *main_xprt;
3140	int status = 0;
3141
3142	xprt_get(xprt);
3143
3144	rcu_read_lock();
3145	main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3146	status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3147				   (struct sockaddr *)&main_xprt->addr);
3148	rcu_read_unlock();
3149	xprt_put(main_xprt);
3150	if (status || !test_bit(XPRT_OFFLINE, &xprt->state))
3151		goto out;
3152
3153	status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3154out:
3155	xprt_put(xprt);
3156	return status;
3157}
3158
3159/* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking
3160 * @clnt rpc_clnt structure
3161 *
3162 * For each offlined transport found in the rpc_clnt structure call
3163 * the function rpc_xprt_probe_trunked() which will determine if this
3164 * transport still belongs to the trunking group.
3165 */
3166void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt,
3167				  struct rpc_add_xprt_test *data)
3168{
3169	struct rpc_xprt_iter xpi;
3170	int ret;
3171
3172	ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi);
3173	if (ret)
3174		return;
3175	for (;;) {
3176		struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
3177
3178		if (!xprt)
3179			break;
3180		ret = rpc_xprt_probe_trunked(clnt, xprt, data);
3181		xprt_put(xprt);
3182		if (ret < 0)
3183			break;
3184		xprt_iter_rewind(&xpi);
3185	}
3186	xprt_iter_destroy(&xpi);
3187}
3188EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts);
3189
3190static int rpc_xprt_offline(struct rpc_clnt *clnt,
3191			    struct rpc_xprt *xprt,
3192			    void *data)
3193{
3194	struct rpc_xprt *main_xprt;
3195	struct rpc_xprt_switch *xps;
3196	int err = 0;
3197
3198	xprt_get(xprt);
3199
3200	rcu_read_lock();
3201	main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3202	xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3203	err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3204				(struct sockaddr *)&main_xprt->addr);
3205	rcu_read_unlock();
3206	xprt_put(main_xprt);
3207	if (err)
3208		goto out;
3209
3210	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {
3211		err = -EINTR;
3212		goto out;
3213	}
3214	xprt_set_offline_locked(xprt, xps);
3215
3216	xprt_release_write(xprt, NULL);
3217out:
3218	xprt_put(xprt);
3219	xprt_switch_put(xps);
3220	return err;
3221}
3222
3223/* rpc_clnt_manage_trunked_xprts -- offline trunked transports
3224 * @clnt rpc_clnt structure
3225 *
3226 * For each active transport found in the rpc_clnt structure call
3227 * the function rpc_xprt_offline() which will identify trunked transports
3228 * and will mark them offline.
3229 */
3230void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt)
3231{
3232	rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL);
3233}
3234EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts);
3235
3236struct connect_timeout_data {
3237	unsigned long connect_timeout;
3238	unsigned long reconnect_timeout;
3239};
3240
3241static int
3242rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
3243		struct rpc_xprt *xprt,
3244		void *data)
3245{
3246	struct connect_timeout_data *timeo = data;
3247
3248	if (xprt->ops->set_connect_timeout)
3249		xprt->ops->set_connect_timeout(xprt,
3250				timeo->connect_timeout,
3251				timeo->reconnect_timeout);
3252	return 0;
3253}
3254
3255void
3256rpc_set_connect_timeout(struct rpc_clnt *clnt,
3257		unsigned long connect_timeout,
3258		unsigned long reconnect_timeout)
3259{
3260	struct connect_timeout_data timeout = {
3261		.connect_timeout = connect_timeout,
3262		.reconnect_timeout = reconnect_timeout,
3263	};
3264	rpc_clnt_iterate_for_each_xprt(clnt,
3265			rpc_xprt_set_connect_timeout,
3266			&timeout);
3267}
3268EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
3269
3270void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3271{
3272	struct rpc_xprt_switch *xps;
3273
3274	xps = rpc_clnt_xprt_switch_get(clnt);
3275	xprt_set_online_locked(xprt, xps);
3276	xprt_switch_put(xps);
3277}
 
3278
3279void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3280{
3281	struct rpc_xprt_switch *xps;
3282
3283	if (rpc_clnt_xprt_switch_has_addr(clnt,
3284		(const struct sockaddr *)&xprt->addr)) {
3285		return rpc_clnt_xprt_set_online(clnt, xprt);
3286	}
3287
3288	xps = rpc_clnt_xprt_switch_get(clnt);
3289	rpc_xprt_switch_add_xprt(xps, xprt);
3290	xprt_switch_put(xps);
3291}
3292EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3293
3294void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3295{
3296	struct rpc_xprt_switch *xps;
3297
3298	rcu_read_lock();
3299	xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3300	rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3301				    xprt, 0);
3302	xps->xps_nunique_destaddr_xprts--;
3303	rcu_read_unlock();
3304}
3305EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt);
3306
3307bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3308				   const struct sockaddr *sap)
3309{
3310	struct rpc_xprt_switch *xps;
3311	bool ret;
3312
3313	rcu_read_lock();
3314	xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3315	ret = rpc_xprt_switch_has_addr(xps, sap);
3316	rcu_read_unlock();
3317	return ret;
3318}
3319EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3320
3321#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3322static void rpc_show_header(void)
3323{
3324	printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3325		"-timeout ---ops--\n");
3326}
3327
3328static void rpc_show_task(const struct rpc_clnt *clnt,
3329			  const struct rpc_task *task)
3330{
3331	const char *rpc_waitq = "none";
3332
3333	if (RPC_IS_QUEUED(task))
3334		rpc_waitq = rpc_qname(task->tk_waitqueue);
3335
3336	printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3337		task->tk_pid, task->tk_flags, task->tk_status,
3338		clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3339		clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3340		task->tk_action, rpc_waitq);
3341}
3342
3343void rpc_show_tasks(struct net *net)
3344{
3345	struct rpc_clnt *clnt;
3346	struct rpc_task *task;
3347	int header = 0;
3348	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3349
3350	spin_lock(&sn->rpc_client_lock);
3351	list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3352		spin_lock(&clnt->cl_lock);
3353		list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3354			if (!header) {
3355				rpc_show_header();
3356				header++;
3357			}
3358			rpc_show_task(clnt, task);
3359		}
3360		spin_unlock(&clnt->cl_lock);
3361	}
3362	spin_unlock(&sn->rpc_client_lock);
3363}
3364#endif
3365
3366#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3367static int
3368rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3369		struct rpc_xprt *xprt,
3370		void *dummy)
3371{
3372	return xprt_enable_swap(xprt);
3373}
3374
3375int
3376rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3377{
3378	while (clnt != clnt->cl_parent)
3379		clnt = clnt->cl_parent;
3380	if (atomic_inc_return(&clnt->cl_swapper) == 1)
3381		return rpc_clnt_iterate_for_each_xprt(clnt,
3382				rpc_clnt_swap_activate_callback, NULL);
3383	return 0;
3384}
3385EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3386
3387static int
3388rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3389		struct rpc_xprt *xprt,
3390		void *dummy)
3391{
3392	xprt_disable_swap(xprt);
3393	return 0;
3394}
3395
3396void
3397rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3398{
3399	while (clnt != clnt->cl_parent)
3400		clnt = clnt->cl_parent;
3401	if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3402		rpc_clnt_iterate_for_each_xprt(clnt,
3403				rpc_clnt_swap_deactivate_callback, NULL);
3404}
3405EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3406#endif /* CONFIG_SUNRPC_SWAP */