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