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v5.14.15
   1/*
   2 *  fs/nfs/nfs4state.c
   3 *
   4 *  Client-side XDR for NFSv4.
   5 *
   6 *  Copyright (c) 2002 The Regents of the University of Michigan.
   7 *  All rights reserved.
   8 *
   9 *  Kendrick Smith <kmsmith@umich.edu>
  10 *
  11 *  Redistribution and use in source and binary forms, with or without
  12 *  modification, are permitted provided that the following conditions
  13 *  are met:
  14 *
  15 *  1. Redistributions of source code must retain the above copyright
  16 *     notice, this list of conditions and the following disclaimer.
  17 *  2. Redistributions in binary form must reproduce the above copyright
  18 *     notice, this list of conditions and the following disclaimer in the
  19 *     documentation and/or other materials provided with the distribution.
  20 *  3. Neither the name of the University nor the names of its
  21 *     contributors may be used to endorse or promote products derived
  22 *     from this software without specific prior written permission.
  23 *
  24 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  25 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  26 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  27 *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  31 *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35 *
  36 * Implementation of the NFSv4 state model.  For the time being,
  37 * this is minimal, but will be made much more complex in a
  38 * subsequent patch.
  39 */
  40
  41#include <linux/kernel.h>
  42#include <linux/slab.h>
  43#include <linux/fs.h>
  44#include <linux/nfs_fs.h>
  45#include <linux/kthread.h>
  46#include <linux/module.h>
  47#include <linux/random.h>
  48#include <linux/ratelimit.h>
  49#include <linux/workqueue.h>
  50#include <linux/bitops.h>
  51#include <linux/jiffies.h>
 
  52
  53#include <linux/sunrpc/clnt.h>
  54
  55#include "nfs4_fs.h"
  56#include "callback.h"
  57#include "delegation.h"
  58#include "internal.h"
  59#include "nfs4idmap.h"
  60#include "nfs4session.h"
  61#include "pnfs.h"
  62#include "netns.h"
  63#include "nfs4trace.h"
  64
  65#define NFSDBG_FACILITY		NFSDBG_STATE
  66
  67#define OPENOWNER_POOL_SIZE	8
  68
 
 
  69const nfs4_stateid zero_stateid = {
  70	{ .data = { 0 } },
  71	.type = NFS4_SPECIAL_STATEID_TYPE,
  72};
  73const nfs4_stateid invalid_stateid = {
  74	{
  75		/* Funky initialiser keeps older gcc versions happy */
  76		.data = { 0xff, 0xff, 0xff, 0xff, 0 },
  77	},
  78	.type = NFS4_INVALID_STATEID_TYPE,
  79};
  80
  81const nfs4_stateid current_stateid = {
  82	{
  83		/* Funky initialiser keeps older gcc versions happy */
  84		.data = { 0x0, 0x0, 0x0, 0x1, 0 },
  85	},
  86	.type = NFS4_SPECIAL_STATEID_TYPE,
  87};
  88
  89static DEFINE_MUTEX(nfs_clid_init_mutex);
  90
  91static int nfs4_setup_state_renewal(struct nfs_client *clp)
  92{
  93	int status;
  94	struct nfs_fsinfo fsinfo;
  95
  96	if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
  97		nfs4_schedule_state_renewal(clp);
  98		return 0;
  99	}
 100
 101	status = nfs4_proc_get_lease_time(clp, &fsinfo);
 102	if (status == 0) {
 103		nfs4_set_lease_period(clp, fsinfo.lease_time * HZ);
 104		nfs4_schedule_state_renewal(clp);
 105	}
 106
 107	return status;
 108}
 109
 110int nfs4_init_clientid(struct nfs_client *clp, const struct cred *cred)
 111{
 112	struct nfs4_setclientid_res clid = {
 113		.clientid = clp->cl_clientid,
 114		.confirm = clp->cl_confirm,
 115	};
 116	unsigned short port;
 117	int status;
 118	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 119
 120	if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 121		goto do_confirm;
 122	port = nn->nfs_callback_tcpport;
 123	if (clp->cl_addr.ss_family == AF_INET6)
 124		port = nn->nfs_callback_tcpport6;
 125
 126	status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
 127	if (status != 0)
 128		goto out;
 129	clp->cl_clientid = clid.clientid;
 130	clp->cl_confirm = clid.confirm;
 131	set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 132do_confirm:
 133	status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
 134	if (status != 0)
 135		goto out;
 136	clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 137	nfs4_setup_state_renewal(clp);
 138out:
 139	return status;
 140}
 141
 142/**
 143 * nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
 144 *
 145 * @clp: nfs_client under test
 146 * @result: OUT: found nfs_client, or clp
 147 * @cred: credential to use for trunking test
 148 *
 149 * Returns zero, a negative errno, or a negative NFS4ERR status.
 150 * If zero is returned, an nfs_client pointer is planted in
 151 * "result".
 152 *
 153 * Note: The returned client may not yet be marked ready.
 154 */
 155int nfs40_discover_server_trunking(struct nfs_client *clp,
 156				   struct nfs_client **result,
 157				   const struct cred *cred)
 158{
 159	struct nfs4_setclientid_res clid = {
 160		.clientid = clp->cl_clientid,
 161		.confirm = clp->cl_confirm,
 162	};
 163	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 164	unsigned short port;
 165	int status;
 166
 167	port = nn->nfs_callback_tcpport;
 168	if (clp->cl_addr.ss_family == AF_INET6)
 169		port = nn->nfs_callback_tcpport6;
 170
 171	status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
 172	if (status != 0)
 173		goto out;
 174	clp->cl_clientid = clid.clientid;
 175	clp->cl_confirm = clid.confirm;
 176
 177	status = nfs40_walk_client_list(clp, result, cred);
 178	if (status == 0) {
 179		/* Sustain the lease, even if it's empty.  If the clientid4
 180		 * goes stale it's of no use for trunking discovery. */
 181		nfs4_schedule_state_renewal(*result);
 182
 183		/* If the client state need to recover, do it. */
 184		if (clp->cl_state)
 185			nfs4_schedule_state_manager(clp);
 186	}
 187out:
 188	return status;
 189}
 190
 191const struct cred *nfs4_get_machine_cred(struct nfs_client *clp)
 192{
 193	return get_cred(rpc_machine_cred());
 194}
 195
 196static void nfs4_root_machine_cred(struct nfs_client *clp)
 197{
 198
 199	/* Force root creds instead of machine */
 200	clp->cl_principal = NULL;
 201	clp->cl_rpcclient->cl_principal = NULL;
 202}
 203
 204static const struct cred *
 205nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 206{
 207	const struct cred *cred = NULL;
 208	struct nfs4_state_owner *sp;
 209	struct rb_node *pos;
 210
 211	for (pos = rb_first(&server->state_owners);
 212	     pos != NULL;
 213	     pos = rb_next(pos)) {
 214		sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 215		if (list_empty(&sp->so_states))
 216			continue;
 217		cred = get_cred(sp->so_cred);
 218		break;
 219	}
 220	return cred;
 221}
 222
 223/**
 224 * nfs4_get_renew_cred - Acquire credential for a renew operation
 225 * @clp: client state handle
 226 *
 227 * Returns an rpc_cred with reference count bumped, or NULL.
 228 * Caller must hold clp->cl_lock.
 229 */
 230const struct cred *nfs4_get_renew_cred(struct nfs_client *clp)
 231{
 232	const struct cred *cred = NULL;
 233	struct nfs_server *server;
 234
 235	/* Use machine credentials if available */
 236	cred = nfs4_get_machine_cred(clp);
 237	if (cred != NULL)
 238		goto out;
 239
 240	spin_lock(&clp->cl_lock);
 241	rcu_read_lock();
 242	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 243		cred = nfs4_get_renew_cred_server_locked(server);
 244		if (cred != NULL)
 245			break;
 246	}
 247	rcu_read_unlock();
 248	spin_unlock(&clp->cl_lock);
 249
 250out:
 251	return cred;
 252}
 253
 254static void nfs4_end_drain_slot_table(struct nfs4_slot_table *tbl)
 255{
 256	if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
 257		spin_lock(&tbl->slot_tbl_lock);
 258		nfs41_wake_slot_table(tbl);
 259		spin_unlock(&tbl->slot_tbl_lock);
 260	}
 261}
 262
 263static void nfs4_end_drain_session(struct nfs_client *clp)
 264{
 265	struct nfs4_session *ses = clp->cl_session;
 266
 267	if (clp->cl_slot_tbl) {
 268		nfs4_end_drain_slot_table(clp->cl_slot_tbl);
 269		return;
 270	}
 271
 272	if (ses != NULL) {
 273		nfs4_end_drain_slot_table(&ses->bc_slot_table);
 274		nfs4_end_drain_slot_table(&ses->fc_slot_table);
 275	}
 276}
 277
 278static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
 279{
 280	set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
 281	spin_lock(&tbl->slot_tbl_lock);
 282	if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
 283		reinit_completion(&tbl->complete);
 284		spin_unlock(&tbl->slot_tbl_lock);
 285		return wait_for_completion_interruptible(&tbl->complete);
 286	}
 287	spin_unlock(&tbl->slot_tbl_lock);
 288	return 0;
 289}
 290
 291static int nfs4_begin_drain_session(struct nfs_client *clp)
 292{
 293	struct nfs4_session *ses = clp->cl_session;
 294	int ret;
 295
 296	if (clp->cl_slot_tbl)
 297		return nfs4_drain_slot_tbl(clp->cl_slot_tbl);
 298
 299	/* back channel */
 300	ret = nfs4_drain_slot_tbl(&ses->bc_slot_table);
 301	if (ret)
 302		return ret;
 303	/* fore channel */
 304	return nfs4_drain_slot_tbl(&ses->fc_slot_table);
 305}
 306
 307#if defined(CONFIG_NFS_V4_1)
 308
 309static void nfs41_finish_session_reset(struct nfs_client *clp)
 310{
 311	clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 312	clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
 313	/* create_session negotiated new slot table */
 314	clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
 315	nfs4_setup_state_renewal(clp);
 316}
 317
 318int nfs41_init_clientid(struct nfs_client *clp, const struct cred *cred)
 319{
 320	int status;
 321
 322	if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 323		goto do_confirm;
 324	status = nfs4_proc_exchange_id(clp, cred);
 325	if (status != 0)
 326		goto out;
 327	set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 328do_confirm:
 329	status = nfs4_proc_create_session(clp, cred);
 330	if (status != 0)
 331		goto out;
 
 
 332	nfs41_finish_session_reset(clp);
 333	nfs_mark_client_ready(clp, NFS_CS_READY);
 334out:
 335	return status;
 336}
 337
 338/**
 339 * nfs41_discover_server_trunking - Detect server IP address trunking (mv1)
 340 *
 341 * @clp: nfs_client under test
 342 * @result: OUT: found nfs_client, or clp
 343 * @cred: credential to use for trunking test
 344 *
 345 * Returns NFS4_OK, a negative errno, or a negative NFS4ERR status.
 346 * If NFS4_OK is returned, an nfs_client pointer is planted in
 347 * "result".
 348 *
 349 * Note: The returned client may not yet be marked ready.
 350 */
 351int nfs41_discover_server_trunking(struct nfs_client *clp,
 352				   struct nfs_client **result,
 353				   const struct cred *cred)
 354{
 355	int status;
 356
 357	status = nfs4_proc_exchange_id(clp, cred);
 358	if (status != NFS4_OK)
 359		return status;
 360
 361	status = nfs41_walk_client_list(clp, result, cred);
 362	if (status < 0)
 363		return status;
 364	if (clp != *result)
 365		return 0;
 366
 367	/*
 368	 * Purge state if the client id was established in a prior
 369	 * instance and the client id could not have arrived on the
 370	 * server via Transparent State Migration.
 371	 */
 372	if (clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R) {
 373		if (!test_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags))
 374			set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
 375		else
 376			set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 377	}
 378	nfs4_schedule_state_manager(clp);
 379	status = nfs_wait_client_init_complete(clp);
 380	if (status < 0)
 381		nfs_put_client(clp);
 382	return status;
 383}
 384
 385#endif /* CONFIG_NFS_V4_1 */
 386
 387/**
 388 * nfs4_get_clid_cred - Acquire credential for a setclientid operation
 389 * @clp: client state handle
 390 *
 391 * Returns a cred with reference count bumped, or NULL.
 392 */
 393const struct cred *nfs4_get_clid_cred(struct nfs_client *clp)
 394{
 395	const struct cred *cred;
 396
 397	cred = nfs4_get_machine_cred(clp);
 398	return cred;
 399}
 400
 401static struct nfs4_state_owner *
 402nfs4_find_state_owner_locked(struct nfs_server *server, const struct cred *cred)
 403{
 404	struct rb_node **p = &server->state_owners.rb_node,
 405		       *parent = NULL;
 406	struct nfs4_state_owner *sp;
 407	int cmp;
 408
 409	while (*p != NULL) {
 410		parent = *p;
 411		sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 412		cmp = cred_fscmp(cred, sp->so_cred);
 413
 414		if (cmp < 0)
 415			p = &parent->rb_left;
 416		else if (cmp > 0)
 417			p = &parent->rb_right;
 418		else {
 419			if (!list_empty(&sp->so_lru))
 420				list_del_init(&sp->so_lru);
 421			atomic_inc(&sp->so_count);
 422			return sp;
 423		}
 424	}
 425	return NULL;
 426}
 427
 428static struct nfs4_state_owner *
 429nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 430{
 431	struct nfs_server *server = new->so_server;
 432	struct rb_node **p = &server->state_owners.rb_node,
 433		       *parent = NULL;
 434	struct nfs4_state_owner *sp;
 435	int cmp;
 436
 437	while (*p != NULL) {
 438		parent = *p;
 439		sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 440		cmp = cred_fscmp(new->so_cred, sp->so_cred);
 441
 442		if (cmp < 0)
 443			p = &parent->rb_left;
 444		else if (cmp > 0)
 445			p = &parent->rb_right;
 446		else {
 447			if (!list_empty(&sp->so_lru))
 448				list_del_init(&sp->so_lru);
 449			atomic_inc(&sp->so_count);
 450			return sp;
 451		}
 452	}
 453	rb_link_node(&new->so_server_node, parent, p);
 454	rb_insert_color(&new->so_server_node, &server->state_owners);
 455	return new;
 456}
 457
 458static void
 459nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 460{
 461	struct nfs_server *server = sp->so_server;
 462
 463	if (!RB_EMPTY_NODE(&sp->so_server_node))
 464		rb_erase(&sp->so_server_node, &server->state_owners);
 465}
 466
 467static void
 468nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
 469{
 470	sc->create_time = ktime_get();
 471	sc->flags = 0;
 472	sc->counter = 0;
 473	spin_lock_init(&sc->lock);
 474	INIT_LIST_HEAD(&sc->list);
 475	rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
 476}
 477
 478static void
 479nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
 480{
 481	rpc_destroy_wait_queue(&sc->wait);
 482}
 483
 484/*
 485 * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 486 * create a new state_owner.
 487 *
 488 */
 489static struct nfs4_state_owner *
 490nfs4_alloc_state_owner(struct nfs_server *server,
 491		const struct cred *cred,
 492		gfp_t gfp_flags)
 493{
 494	struct nfs4_state_owner *sp;
 495
 496	sp = kzalloc(sizeof(*sp), gfp_flags);
 497	if (!sp)
 498		return NULL;
 499	sp->so_seqid.owner_id = ida_simple_get(&server->openowner_id, 0, 0,
 500						gfp_flags);
 501	if (sp->so_seqid.owner_id < 0) {
 502		kfree(sp);
 503		return NULL;
 504	}
 505	sp->so_server = server;
 506	sp->so_cred = get_cred(cred);
 507	spin_lock_init(&sp->so_lock);
 508	INIT_LIST_HEAD(&sp->so_states);
 509	nfs4_init_seqid_counter(&sp->so_seqid);
 510	atomic_set(&sp->so_count, 1);
 511	INIT_LIST_HEAD(&sp->so_lru);
 512	seqcount_spinlock_init(&sp->so_reclaim_seqcount, &sp->so_lock);
 513	mutex_init(&sp->so_delegreturn_mutex);
 514	return sp;
 515}
 516
 517static void
 518nfs4_reset_state_owner(struct nfs4_state_owner *sp)
 519{
 520	/* This state_owner is no longer usable, but must
 521	 * remain in place so that state recovery can find it
 522	 * and the opens associated with it.
 523	 * It may also be used for new 'open' request to
 524	 * return a delegation to the server.
 525	 * So update the 'create_time' so that it looks like
 526	 * a new state_owner.  This will cause the server to
 527	 * request an OPEN_CONFIRM to start a new sequence.
 528	 */
 529	sp->so_seqid.create_time = ktime_get();
 530}
 531
 532static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 533{
 534	nfs4_destroy_seqid_counter(&sp->so_seqid);
 535	put_cred(sp->so_cred);
 536	ida_simple_remove(&sp->so_server->openowner_id, sp->so_seqid.owner_id);
 537	kfree(sp);
 538}
 539
 540static void nfs4_gc_state_owners(struct nfs_server *server)
 541{
 542	struct nfs_client *clp = server->nfs_client;
 543	struct nfs4_state_owner *sp, *tmp;
 544	unsigned long time_min, time_max;
 545	LIST_HEAD(doomed);
 546
 547	spin_lock(&clp->cl_lock);
 548	time_max = jiffies;
 549	time_min = (long)time_max - (long)clp->cl_lease_time;
 550	list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 551		/* NB: LRU is sorted so that oldest is at the head */
 552		if (time_in_range(sp->so_expires, time_min, time_max))
 553			break;
 554		list_move(&sp->so_lru, &doomed);
 555		nfs4_remove_state_owner_locked(sp);
 556	}
 557	spin_unlock(&clp->cl_lock);
 558
 559	list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 560		list_del(&sp->so_lru);
 561		nfs4_free_state_owner(sp);
 562	}
 563}
 564
 565/**
 566 * nfs4_get_state_owner - Look up a state owner given a credential
 567 * @server: nfs_server to search
 568 * @cred: RPC credential to match
 569 * @gfp_flags: allocation mode
 570 *
 571 * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 572 */
 573struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 574					      const struct cred *cred,
 575					      gfp_t gfp_flags)
 576{
 577	struct nfs_client *clp = server->nfs_client;
 578	struct nfs4_state_owner *sp, *new;
 579
 580	spin_lock(&clp->cl_lock);
 581	sp = nfs4_find_state_owner_locked(server, cred);
 582	spin_unlock(&clp->cl_lock);
 583	if (sp != NULL)
 584		goto out;
 585	new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 586	if (new == NULL)
 587		goto out;
 588	spin_lock(&clp->cl_lock);
 589	sp = nfs4_insert_state_owner_locked(new);
 590	spin_unlock(&clp->cl_lock);
 591	if (sp != new)
 592		nfs4_free_state_owner(new);
 593out:
 594	nfs4_gc_state_owners(server);
 595	return sp;
 596}
 597
 598/**
 599 * nfs4_put_state_owner - Release a nfs4_state_owner
 600 * @sp: state owner data to release
 601 *
 602 * Note that we keep released state owners on an LRU
 603 * list.
 604 * This caches valid state owners so that they can be
 605 * reused, to avoid the OPEN_CONFIRM on minor version 0.
 606 * It also pins the uniquifier of dropped state owners for
 607 * a while, to ensure that those state owner names are
 608 * never reused.
 609 */
 610void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 611{
 612	struct nfs_server *server = sp->so_server;
 613	struct nfs_client *clp = server->nfs_client;
 614
 615	if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 616		return;
 617
 618	sp->so_expires = jiffies;
 619	list_add_tail(&sp->so_lru, &server->state_owners_lru);
 620	spin_unlock(&clp->cl_lock);
 621}
 622
 623/**
 624 * nfs4_purge_state_owners - Release all cached state owners
 625 * @server: nfs_server with cached state owners to release
 626 * @head: resulting list of state owners
 627 *
 628 * Called at umount time.  Remaining state owners will be on
 629 * the LRU with ref count of zero.
 630 * Note that the state owners are not freed, but are added
 631 * to the list @head, which can later be used as an argument
 632 * to nfs4_free_state_owners.
 633 */
 634void nfs4_purge_state_owners(struct nfs_server *server, struct list_head *head)
 635{
 636	struct nfs_client *clp = server->nfs_client;
 637	struct nfs4_state_owner *sp, *tmp;
 638
 639	spin_lock(&clp->cl_lock);
 640	list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 641		list_move(&sp->so_lru, head);
 642		nfs4_remove_state_owner_locked(sp);
 643	}
 644	spin_unlock(&clp->cl_lock);
 645}
 646
 647/**
 648 * nfs4_free_state_owners - Release all cached state owners
 649 * @head: resulting list of state owners
 650 *
 651 * Frees a list of state owners that was generated by
 652 * nfs4_purge_state_owners
 653 */
 654void nfs4_free_state_owners(struct list_head *head)
 655{
 656	struct nfs4_state_owner *sp, *tmp;
 657
 658	list_for_each_entry_safe(sp, tmp, head, so_lru) {
 659		list_del(&sp->so_lru);
 660		nfs4_free_state_owner(sp);
 661	}
 662}
 663
 664static struct nfs4_state *
 665nfs4_alloc_open_state(void)
 666{
 667	struct nfs4_state *state;
 668
 669	state = kzalloc(sizeof(*state), GFP_NOFS);
 670	if (!state)
 671		return NULL;
 672	refcount_set(&state->count, 1);
 673	INIT_LIST_HEAD(&state->lock_states);
 674	spin_lock_init(&state->state_lock);
 675	seqlock_init(&state->seqlock);
 676	init_waitqueue_head(&state->waitq);
 677	return state;
 678}
 679
 680void
 681nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 682{
 683	if (state->state == fmode)
 684		return;
 685	/* NB! List reordering - see the reclaim code for why.  */
 686	if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 687		if (fmode & FMODE_WRITE)
 688			list_move(&state->open_states, &state->owner->so_states);
 689		else
 690			list_move_tail(&state->open_states, &state->owner->so_states);
 691	}
 692	state->state = fmode;
 693}
 694
 695static struct nfs4_state *
 696__nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 697{
 698	struct nfs_inode *nfsi = NFS_I(inode);
 699	struct nfs4_state *state;
 700
 701	list_for_each_entry_rcu(state, &nfsi->open_states, inode_states) {
 702		if (state->owner != owner)
 703			continue;
 704		if (!nfs4_valid_open_stateid(state))
 705			continue;
 706		if (refcount_inc_not_zero(&state->count))
 707			return state;
 708	}
 709	return NULL;
 710}
 711
 712static void
 713nfs4_free_open_state(struct nfs4_state *state)
 714{
 715	kfree_rcu(state, rcu_head);
 716}
 717
 718struct nfs4_state *
 719nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 720{
 721	struct nfs4_state *state, *new;
 722	struct nfs_inode *nfsi = NFS_I(inode);
 723
 724	rcu_read_lock();
 725	state = __nfs4_find_state_byowner(inode, owner);
 726	rcu_read_unlock();
 727	if (state)
 728		goto out;
 729	new = nfs4_alloc_open_state();
 730	spin_lock(&owner->so_lock);
 731	spin_lock(&inode->i_lock);
 732	state = __nfs4_find_state_byowner(inode, owner);
 733	if (state == NULL && new != NULL) {
 734		state = new;
 735		state->owner = owner;
 736		atomic_inc(&owner->so_count);
 737		ihold(inode);
 738		state->inode = inode;
 739		list_add_rcu(&state->inode_states, &nfsi->open_states);
 740		spin_unlock(&inode->i_lock);
 741		/* Note: The reclaim code dictates that we add stateless
 742		 * and read-only stateids to the end of the list */
 743		list_add_tail(&state->open_states, &owner->so_states);
 744		spin_unlock(&owner->so_lock);
 745	} else {
 746		spin_unlock(&inode->i_lock);
 747		spin_unlock(&owner->so_lock);
 748		if (new)
 749			nfs4_free_open_state(new);
 750	}
 751out:
 752	return state;
 753}
 754
 755void nfs4_put_open_state(struct nfs4_state *state)
 756{
 757	struct inode *inode = state->inode;
 758	struct nfs4_state_owner *owner = state->owner;
 759
 760	if (!refcount_dec_and_lock(&state->count, &owner->so_lock))
 761		return;
 762	spin_lock(&inode->i_lock);
 763	list_del_rcu(&state->inode_states);
 764	list_del(&state->open_states);
 765	spin_unlock(&inode->i_lock);
 766	spin_unlock(&owner->so_lock);
 767	nfs4_inode_return_delegation_on_close(inode);
 768	iput(inode);
 769	nfs4_free_open_state(state);
 770	nfs4_put_state_owner(owner);
 771}
 772
 773/*
 774 * Close the current file.
 775 */
 776static void __nfs4_close(struct nfs4_state *state,
 777		fmode_t fmode, gfp_t gfp_mask, int wait)
 778{
 779	struct nfs4_state_owner *owner = state->owner;
 780	int call_close = 0;
 781	fmode_t newstate;
 782
 783	atomic_inc(&owner->so_count);
 784	/* Protect against nfs4_find_state() */
 785	spin_lock(&owner->so_lock);
 786	switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 787		case FMODE_READ:
 788			state->n_rdonly--;
 789			break;
 790		case FMODE_WRITE:
 791			state->n_wronly--;
 792			break;
 793		case FMODE_READ|FMODE_WRITE:
 794			state->n_rdwr--;
 795	}
 796	newstate = FMODE_READ|FMODE_WRITE;
 797	if (state->n_rdwr == 0) {
 798		if (state->n_rdonly == 0) {
 799			newstate &= ~FMODE_READ;
 800			call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 801			call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 802		}
 803		if (state->n_wronly == 0) {
 804			newstate &= ~FMODE_WRITE;
 805			call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 806			call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 807		}
 808		if (newstate == 0)
 809			clear_bit(NFS_DELEGATED_STATE, &state->flags);
 810	}
 811	nfs4_state_set_mode_locked(state, newstate);
 812	spin_unlock(&owner->so_lock);
 813
 814	if (!call_close) {
 815		nfs4_put_open_state(state);
 816		nfs4_put_state_owner(owner);
 817	} else
 818		nfs4_do_close(state, gfp_mask, wait);
 819}
 820
 821void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 822{
 823	__nfs4_close(state, fmode, GFP_NOFS, 0);
 824}
 825
 826void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 827{
 828	__nfs4_close(state, fmode, GFP_KERNEL, 1);
 829}
 830
 831/*
 832 * Search the state->lock_states for an existing lock_owner
 833 * that is compatible with either of the given owners.
 834 * If the second is non-zero, then the first refers to a Posix-lock
 835 * owner (current->files) and the second refers to a flock/OFD
 836 * owner (struct file*).  In that case, prefer a match for the first
 837 * owner.
 838 * If both sorts of locks are held on the one file we cannot know
 839 * which stateid was intended to be used, so a "correct" choice cannot
 840 * be made.  Failing that, a "consistent" choice is preferable.  The
 841 * consistent choice we make is to prefer the first owner, that of a
 842 * Posix lock.
 843 */
 844static struct nfs4_lock_state *
 845__nfs4_find_lock_state(struct nfs4_state *state,
 846		       fl_owner_t fl_owner, fl_owner_t fl_owner2)
 847{
 848	struct nfs4_lock_state *pos, *ret = NULL;
 849	list_for_each_entry(pos, &state->lock_states, ls_locks) {
 850		if (pos->ls_owner == fl_owner) {
 851			ret = pos;
 852			break;
 853		}
 854		if (pos->ls_owner == fl_owner2)
 855			ret = pos;
 856	}
 857	if (ret)
 858		refcount_inc(&ret->ls_count);
 859	return ret;
 860}
 861
 862/*
 863 * Return a compatible lock_state. If no initialized lock_state structure
 864 * exists, return an uninitialized one.
 865 *
 866 */
 867static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 868{
 869	struct nfs4_lock_state *lsp;
 870	struct nfs_server *server = state->owner->so_server;
 871
 872	lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 873	if (lsp == NULL)
 874		return NULL;
 875	nfs4_init_seqid_counter(&lsp->ls_seqid);
 876	refcount_set(&lsp->ls_count, 1);
 877	lsp->ls_state = state;
 878	lsp->ls_owner = fl_owner;
 879	lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
 880	if (lsp->ls_seqid.owner_id < 0)
 881		goto out_free;
 882	INIT_LIST_HEAD(&lsp->ls_locks);
 883	return lsp;
 884out_free:
 885	kfree(lsp);
 886	return NULL;
 887}
 888
 889void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
 890{
 891	ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
 892	nfs4_destroy_seqid_counter(&lsp->ls_seqid);
 893	kfree(lsp);
 894}
 895
 896/*
 897 * Return a compatible lock_state. If no initialized lock_state structure
 898 * exists, return an uninitialized one.
 899 *
 900 */
 901static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 902{
 903	struct nfs4_lock_state *lsp, *new = NULL;
 904	
 905	for(;;) {
 906		spin_lock(&state->state_lock);
 907		lsp = __nfs4_find_lock_state(state, owner, NULL);
 908		if (lsp != NULL)
 909			break;
 910		if (new != NULL) {
 911			list_add(&new->ls_locks, &state->lock_states);
 912			set_bit(LK_STATE_IN_USE, &state->flags);
 913			lsp = new;
 914			new = NULL;
 915			break;
 916		}
 917		spin_unlock(&state->state_lock);
 918		new = nfs4_alloc_lock_state(state, owner);
 919		if (new == NULL)
 920			return NULL;
 921	}
 922	spin_unlock(&state->state_lock);
 923	if (new != NULL)
 924		nfs4_free_lock_state(state->owner->so_server, new);
 925	return lsp;
 926}
 927
 928/*
 929 * Release reference to lock_state, and free it if we see that
 930 * it is no longer in use
 931 */
 932void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 933{
 934	struct nfs_server *server;
 935	struct nfs4_state *state;
 936
 937	if (lsp == NULL)
 938		return;
 939	state = lsp->ls_state;
 940	if (!refcount_dec_and_lock(&lsp->ls_count, &state->state_lock))
 941		return;
 942	list_del(&lsp->ls_locks);
 943	if (list_empty(&state->lock_states))
 944		clear_bit(LK_STATE_IN_USE, &state->flags);
 945	spin_unlock(&state->state_lock);
 946	server = state->owner->so_server;
 947	if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
 948		struct nfs_client *clp = server->nfs_client;
 949
 950		clp->cl_mvops->free_lock_state(server, lsp);
 951	} else
 952		nfs4_free_lock_state(server, lsp);
 953}
 954
 955static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 956{
 957	struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 958
 959	dst->fl_u.nfs4_fl.owner = lsp;
 960	refcount_inc(&lsp->ls_count);
 961}
 962
 963static void nfs4_fl_release_lock(struct file_lock *fl)
 964{
 965	nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 966}
 967
 968static const struct file_lock_operations nfs4_fl_lock_ops = {
 969	.fl_copy_lock = nfs4_fl_copy_lock,
 970	.fl_release_private = nfs4_fl_release_lock,
 971};
 972
 973int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 974{
 975	struct nfs4_lock_state *lsp;
 976
 977	if (fl->fl_ops != NULL)
 978		return 0;
 979	lsp = nfs4_get_lock_state(state, fl->fl_owner);
 980	if (lsp == NULL)
 981		return -ENOMEM;
 982	fl->fl_u.nfs4_fl.owner = lsp;
 983	fl->fl_ops = &nfs4_fl_lock_ops;
 984	return 0;
 985}
 986
 987static int nfs4_copy_lock_stateid(nfs4_stateid *dst,
 988		struct nfs4_state *state,
 989		const struct nfs_lock_context *l_ctx)
 990{
 991	struct nfs4_lock_state *lsp;
 992	fl_owner_t fl_owner, fl_flock_owner;
 993	int ret = -ENOENT;
 994
 995	if (l_ctx == NULL)
 996		goto out;
 997
 998	if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 999		goto out;
1000
1001	fl_owner = l_ctx->lockowner;
1002	fl_flock_owner = l_ctx->open_context->flock_owner;
1003
1004	spin_lock(&state->state_lock);
1005	lsp = __nfs4_find_lock_state(state, fl_owner, fl_flock_owner);
1006	if (lsp && test_bit(NFS_LOCK_LOST, &lsp->ls_flags))
1007		ret = -EIO;
1008	else if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
1009		nfs4_stateid_copy(dst, &lsp->ls_stateid);
1010		ret = 0;
1011	}
1012	spin_unlock(&state->state_lock);
1013	nfs4_put_lock_state(lsp);
1014out:
1015	return ret;
1016}
1017
1018bool nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
1019{
1020	bool ret;
1021	const nfs4_stateid *src;
1022	int seq;
1023
1024	do {
1025		ret = false;
1026		src = &zero_stateid;
1027		seq = read_seqbegin(&state->seqlock);
1028		if (test_bit(NFS_OPEN_STATE, &state->flags)) {
1029			src = &state->open_stateid;
1030			ret = true;
1031		}
1032		nfs4_stateid_copy(dst, src);
1033	} while (read_seqretry(&state->seqlock, seq));
1034	return ret;
1035}
1036
1037/*
1038 * Byte-range lock aware utility to initialize the stateid of read/write
1039 * requests.
1040 */
1041int nfs4_select_rw_stateid(struct nfs4_state *state,
1042		fmode_t fmode, const struct nfs_lock_context *l_ctx,
1043		nfs4_stateid *dst, const struct cred **cred)
1044{
1045	int ret;
1046
1047	if (!nfs4_valid_open_stateid(state))
1048		return -EIO;
1049	if (cred != NULL)
1050		*cred = NULL;
1051	ret = nfs4_copy_lock_stateid(dst, state, l_ctx);
1052	if (ret == -EIO)
1053		/* A lost lock - don't even consider delegations */
1054		goto out;
1055	/* returns true if delegation stateid found and copied */
1056	if (nfs4_copy_delegation_stateid(state->inode, fmode, dst, cred)) {
1057		ret = 0;
1058		goto out;
1059	}
1060	if (ret != -ENOENT)
1061		/* nfs4_copy_delegation_stateid() didn't over-write
1062		 * dst, so it still has the lock stateid which we now
1063		 * choose to use.
1064		 */
1065		goto out;
1066	ret = nfs4_copy_open_stateid(dst, state) ? 0 : -EAGAIN;
1067out:
1068	if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41))
1069		dst->seqid = 0;
1070	return ret;
1071}
1072
1073struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
1074{
1075	struct nfs_seqid *new;
1076
1077	new = kmalloc(sizeof(*new), gfp_mask);
1078	if (new == NULL)
1079		return ERR_PTR(-ENOMEM);
1080	new->sequence = counter;
1081	INIT_LIST_HEAD(&new->list);
1082	new->task = NULL;
1083	return new;
1084}
1085
1086void nfs_release_seqid(struct nfs_seqid *seqid)
1087{
1088	struct nfs_seqid_counter *sequence;
1089
1090	if (seqid == NULL || list_empty(&seqid->list))
1091		return;
1092	sequence = seqid->sequence;
1093	spin_lock(&sequence->lock);
1094	list_del_init(&seqid->list);
1095	if (!list_empty(&sequence->list)) {
1096		struct nfs_seqid *next;
1097
1098		next = list_first_entry(&sequence->list,
1099				struct nfs_seqid, list);
1100		rpc_wake_up_queued_task(&sequence->wait, next->task);
1101	}
1102	spin_unlock(&sequence->lock);
1103}
1104
1105void nfs_free_seqid(struct nfs_seqid *seqid)
1106{
1107	nfs_release_seqid(seqid);
1108	kfree(seqid);
1109}
1110
1111/*
1112 * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
1113 * failed with a seqid incrementing error -
1114 * see comments nfs4.h:seqid_mutating_error()
1115 */
1116static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
1117{
1118	switch (status) {
1119		case 0:
1120			break;
1121		case -NFS4ERR_BAD_SEQID:
1122			if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1123				return;
1124			pr_warn_ratelimited("NFS: v4 server returned a bad"
1125					" sequence-id error on an"
1126					" unconfirmed sequence %p!\n",
1127					seqid->sequence);
1128			return;
1129		case -NFS4ERR_STALE_CLIENTID:
1130		case -NFS4ERR_STALE_STATEID:
1131		case -NFS4ERR_BAD_STATEID:
1132		case -NFS4ERR_BADXDR:
1133		case -NFS4ERR_RESOURCE:
1134		case -NFS4ERR_NOFILEHANDLE:
1135		case -NFS4ERR_MOVED:
1136			/* Non-seqid mutating errors */
1137			return;
1138	}
1139	/*
1140	 * Note: no locking needed as we are guaranteed to be first
1141	 * on the sequence list
1142	 */
1143	seqid->sequence->counter++;
1144}
1145
1146void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1147{
1148	struct nfs4_state_owner *sp;
1149
1150	if (seqid == NULL)
1151		return;
1152
1153	sp = container_of(seqid->sequence, struct nfs4_state_owner, so_seqid);
1154	if (status == -NFS4ERR_BAD_SEQID)
1155		nfs4_reset_state_owner(sp);
1156	if (!nfs4_has_session(sp->so_server->nfs_client))
1157		nfs_increment_seqid(status, seqid);
1158}
1159
1160/*
1161 * Increment the seqid if the LOCK/LOCKU succeeded, or
1162 * failed with a seqid incrementing error -
1163 * see comments nfs4.h:seqid_mutating_error()
1164 */
1165void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1166{
1167	if (seqid != NULL)
1168		nfs_increment_seqid(status, seqid);
1169}
1170
1171int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1172{
1173	struct nfs_seqid_counter *sequence;
1174	int status = 0;
1175
1176	if (seqid == NULL)
1177		goto out;
1178	sequence = seqid->sequence;
1179	spin_lock(&sequence->lock);
1180	seqid->task = task;
1181	if (list_empty(&seqid->list))
1182		list_add_tail(&seqid->list, &sequence->list);
1183	if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1184		goto unlock;
1185	rpc_sleep_on(&sequence->wait, task, NULL);
1186	status = -EAGAIN;
1187unlock:
1188	spin_unlock(&sequence->lock);
1189out:
1190	return status;
1191}
1192
1193static int nfs4_run_state_manager(void *);
1194
1195static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1196{
1197	smp_mb__before_atomic();
1198	clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1199	smp_mb__after_atomic();
1200	wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1201	rpc_wake_up(&clp->cl_rpcwaitq);
1202}
1203
1204/*
1205 * Schedule the nfs_client asynchronous state management routine
1206 */
1207void nfs4_schedule_state_manager(struct nfs_client *clp)
1208{
1209	struct task_struct *task;
1210	char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
 
 
 
 
 
1211
1212	set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
 
 
 
 
 
 
 
 
 
 
1213	if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1214		return;
 
1215	__module_get(THIS_MODULE);
1216	refcount_inc(&clp->cl_count);
1217
1218	/* The rcu_read_lock() is not strictly necessary, as the state
1219	 * manager is the only thread that ever changes the rpc_xprt
1220	 * after it's initialized.  At this point, we're single threaded. */
1221	rcu_read_lock();
1222	snprintf(buf, sizeof(buf), "%s-manager",
1223			rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1224	rcu_read_unlock();
1225	task = kthread_run(nfs4_run_state_manager, clp, "%s", buf);
1226	if (IS_ERR(task)) {
1227		printk(KERN_ERR "%s: kthread_run: %ld\n",
1228			__func__, PTR_ERR(task));
 
 
 
 
1229		nfs4_clear_state_manager_bit(clp);
1230		nfs_put_client(clp);
1231		module_put(THIS_MODULE);
1232	}
1233}
1234
1235/*
1236 * Schedule a lease recovery attempt
1237 */
1238void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1239{
1240	if (!clp)
1241		return;
1242	if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1243		set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1244	dprintk("%s: scheduling lease recovery for server %s\n", __func__,
1245			clp->cl_hostname);
1246	nfs4_schedule_state_manager(clp);
1247}
1248EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1249
1250/**
1251 * nfs4_schedule_migration_recovery - trigger migration recovery
1252 *
1253 * @server: FSID that is migrating
1254 *
1255 * Returns zero if recovery has started, otherwise a negative NFS4ERR
1256 * value is returned.
1257 */
1258int nfs4_schedule_migration_recovery(const struct nfs_server *server)
1259{
1260	struct nfs_client *clp = server->nfs_client;
1261
1262	if (server->fh_expire_type != NFS4_FH_PERSISTENT) {
1263		pr_err("NFS: volatile file handles not supported (server %s)\n",
1264				clp->cl_hostname);
1265		return -NFS4ERR_IO;
1266	}
1267
1268	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
1269		return -NFS4ERR_IO;
1270
1271	dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n",
1272			__func__,
1273			(unsigned long long)server->fsid.major,
1274			(unsigned long long)server->fsid.minor,
1275			clp->cl_hostname);
1276
1277	set_bit(NFS_MIG_IN_TRANSITION,
1278			&((struct nfs_server *)server)->mig_status);
1279	set_bit(NFS4CLNT_MOVED, &clp->cl_state);
1280
1281	nfs4_schedule_state_manager(clp);
1282	return 0;
1283}
1284EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
1285
1286/**
1287 * nfs4_schedule_lease_moved_recovery - start lease-moved recovery
1288 *
1289 * @clp: server to check for moved leases
1290 *
1291 */
1292void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp)
1293{
1294	dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n",
1295		__func__, clp->cl_clientid, clp->cl_hostname);
1296
1297	set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state);
1298	nfs4_schedule_state_manager(clp);
1299}
1300EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery);
1301
1302int nfs4_wait_clnt_recover(struct nfs_client *clp)
1303{
1304	int res;
1305
1306	might_sleep();
1307
1308	refcount_inc(&clp->cl_count);
1309	res = wait_on_bit_action(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
1310				 nfs_wait_bit_killable, TASK_KILLABLE);
 
1311	if (res)
1312		goto out;
1313	if (clp->cl_cons_state < 0)
1314		res = clp->cl_cons_state;
1315out:
1316	nfs_put_client(clp);
1317	return res;
1318}
1319
1320int nfs4_client_recover_expired_lease(struct nfs_client *clp)
1321{
1322	unsigned int loop;
1323	int ret;
1324
1325	for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) {
1326		ret = nfs4_wait_clnt_recover(clp);
1327		if (ret != 0)
1328			break;
1329		if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) &&
1330		    !test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state))
1331			break;
1332		nfs4_schedule_state_manager(clp);
1333		ret = -EIO;
1334	}
1335	return ret;
1336}
1337
1338/*
1339 * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1340 * @clp: client to process
1341 *
1342 * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1343 * resend of the SETCLIENTID and hence re-establish the
1344 * callback channel. Then return all existing delegations.
1345 */
1346static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1347{
1348	set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1349	nfs_expire_all_delegations(clp);
1350	dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__,
1351			clp->cl_hostname);
1352}
1353
1354void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1355{
1356	nfs40_handle_cb_pathdown(clp);
1357	nfs4_schedule_state_manager(clp);
1358}
1359
1360static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1361{
1362
1363	if (!nfs4_valid_open_stateid(state))
1364		return 0;
1365	set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1366	/* Don't recover state that expired before the reboot */
1367	if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1368		clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1369		return 0;
1370	}
1371	set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1372	set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1373	return 1;
1374}
1375
1376int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1377{
1378	if (!nfs4_valid_open_stateid(state))
1379		return 0;
1380	set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1381	clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1382	set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1383	set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1384	return 1;
1385}
1386
1387int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1388{
1389	struct nfs_client *clp = server->nfs_client;
1390
1391	if (!nfs4_state_mark_reclaim_nograce(clp, state))
1392		return -EBADF;
1393	nfs_inode_find_delegation_state_and_recover(state->inode,
1394			&state->stateid);
1395	dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
1396			clp->cl_hostname);
1397	nfs4_schedule_state_manager(clp);
1398	return 0;
1399}
1400EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1401
1402static struct nfs4_lock_state *
1403nfs_state_find_lock_state_by_stateid(struct nfs4_state *state,
1404		const nfs4_stateid *stateid)
1405{
1406	struct nfs4_lock_state *pos;
1407
1408	list_for_each_entry(pos, &state->lock_states, ls_locks) {
1409		if (!test_bit(NFS_LOCK_INITIALIZED, &pos->ls_flags))
1410			continue;
1411		if (nfs4_stateid_match_or_older(&pos->ls_stateid, stateid))
1412			return pos;
1413	}
1414	return NULL;
1415}
1416
1417static bool nfs_state_lock_state_matches_stateid(struct nfs4_state *state,
1418		const nfs4_stateid *stateid)
1419{
1420	bool found = false;
1421
1422	if (test_bit(LK_STATE_IN_USE, &state->flags)) {
1423		spin_lock(&state->state_lock);
1424		if (nfs_state_find_lock_state_by_stateid(state, stateid))
1425			found = true;
1426		spin_unlock(&state->state_lock);
1427	}
1428	return found;
1429}
1430
1431void nfs_inode_find_state_and_recover(struct inode *inode,
1432		const nfs4_stateid *stateid)
1433{
1434	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1435	struct nfs_inode *nfsi = NFS_I(inode);
1436	struct nfs_open_context *ctx;
1437	struct nfs4_state *state;
1438	bool found = false;
1439
1440	rcu_read_lock();
1441	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1442		state = ctx->state;
1443		if (state == NULL)
1444			continue;
1445		if (nfs4_stateid_match_or_older(&state->stateid, stateid) &&
1446		    nfs4_state_mark_reclaim_nograce(clp, state)) {
1447			found = true;
1448			continue;
1449		}
1450		if (test_bit(NFS_OPEN_STATE, &state->flags) &&
1451		    nfs4_stateid_match_or_older(&state->open_stateid, stateid) &&
1452		    nfs4_state_mark_reclaim_nograce(clp, state)) {
1453			found = true;
1454			continue;
1455		}
1456		if (nfs_state_lock_state_matches_stateid(state, stateid) &&
1457		    nfs4_state_mark_reclaim_nograce(clp, state))
1458			found = true;
1459	}
1460	rcu_read_unlock();
1461
1462	nfs_inode_find_delegation_state_and_recover(inode, stateid);
1463	if (found)
1464		nfs4_schedule_state_manager(clp);
1465}
1466
1467static void nfs4_state_mark_open_context_bad(struct nfs4_state *state, int err)
1468{
1469	struct inode *inode = state->inode;
1470	struct nfs_inode *nfsi = NFS_I(inode);
1471	struct nfs_open_context *ctx;
1472
1473	rcu_read_lock();
1474	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1475		if (ctx->state != state)
1476			continue;
1477		set_bit(NFS_CONTEXT_BAD, &ctx->flags);
1478		pr_warn("NFSv4: state recovery failed for open file %pd2, "
1479				"error = %d\n", ctx->dentry, err);
1480	}
1481	rcu_read_unlock();
1482}
1483
1484static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)
1485{
1486	set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags);
1487	nfs4_state_mark_open_context_bad(state, error);
1488}
1489
1490
1491static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1492{
1493	struct inode *inode = state->inode;
1494	struct nfs_inode *nfsi = NFS_I(inode);
1495	struct file_lock *fl;
1496	struct nfs4_lock_state *lsp;
1497	int status = 0;
1498	struct file_lock_context *flctx = inode->i_flctx;
1499	struct list_head *list;
1500
1501	if (flctx == NULL)
1502		return 0;
1503
1504	list = &flctx->flc_posix;
1505
1506	/* Guard against delegation returns and new lock/unlock calls */
1507	down_write(&nfsi->rwsem);
1508	spin_lock(&flctx->flc_lock);
1509restart:
1510	list_for_each_entry(fl, list, fl_list) {
1511		if (nfs_file_open_context(fl->fl_file)->state != state)
1512			continue;
1513		spin_unlock(&flctx->flc_lock);
1514		status = ops->recover_lock(state, fl);
1515		switch (status) {
1516		case 0:
1517			break;
1518		case -ETIMEDOUT:
1519		case -ESTALE:
1520		case -NFS4ERR_ADMIN_REVOKED:
1521		case -NFS4ERR_STALE_STATEID:
1522		case -NFS4ERR_BAD_STATEID:
1523		case -NFS4ERR_EXPIRED:
1524		case -NFS4ERR_NO_GRACE:
1525		case -NFS4ERR_STALE_CLIENTID:
1526		case -NFS4ERR_BADSESSION:
1527		case -NFS4ERR_BADSLOT:
1528		case -NFS4ERR_BAD_HIGH_SLOT:
1529		case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1530			goto out;
1531		default:
1532			pr_err("NFS: %s: unhandled error %d\n",
1533					__func__, status);
1534			fallthrough;
1535		case -ENOMEM:
1536		case -NFS4ERR_DENIED:
1537		case -NFS4ERR_RECLAIM_BAD:
1538		case -NFS4ERR_RECLAIM_CONFLICT:
1539			lsp = fl->fl_u.nfs4_fl.owner;
1540			if (lsp)
1541				set_bit(NFS_LOCK_LOST, &lsp->ls_flags);
1542			status = 0;
1543		}
1544		spin_lock(&flctx->flc_lock);
1545	}
1546	if (list == &flctx->flc_posix) {
1547		list = &flctx->flc_flock;
1548		goto restart;
1549	}
1550	spin_unlock(&flctx->flc_lock);
1551out:
1552	up_write(&nfsi->rwsem);
1553	return status;
1554}
1555
1556#ifdef CONFIG_NFS_V4_2
1557static void nfs42_complete_copies(struct nfs4_state_owner *sp, struct nfs4_state *state)
1558{
1559	struct nfs4_copy_state *copy;
1560
1561	if (!test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags) &&
1562		!test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags))
1563		return;
1564
1565	spin_lock(&sp->so_server->nfs_client->cl_lock);
1566	list_for_each_entry(copy, &sp->so_server->ss_copies, copies) {
1567		if ((test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags) &&
1568				!nfs4_stateid_match_other(&state->stateid,
1569				&copy->parent_dst_state->stateid)))
1570				continue;
1571		copy->flags = 1;
1572		if (test_and_clear_bit(NFS_CLNT_DST_SSC_COPY_STATE,
1573				&state->flags)) {
1574			clear_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags);
1575			complete(&copy->completion);
1576		}
1577	}
1578	list_for_each_entry(copy, &sp->so_server->ss_copies, src_copies) {
1579		if ((test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags) &&
1580				!nfs4_stateid_match_other(&state->stateid,
1581				&copy->parent_src_state->stateid)))
1582				continue;
1583		copy->flags = 1;
1584		if (test_and_clear_bit(NFS_CLNT_DST_SSC_COPY_STATE,
1585				&state->flags))
1586			complete(&copy->completion);
1587	}
1588	spin_unlock(&sp->so_server->nfs_client->cl_lock);
1589}
1590#else /* !CONFIG_NFS_V4_2 */
1591static inline void nfs42_complete_copies(struct nfs4_state_owner *sp,
1592					 struct nfs4_state *state)
1593{
1594}
1595#endif /* CONFIG_NFS_V4_2 */
1596
1597static int __nfs4_reclaim_open_state(struct nfs4_state_owner *sp, struct nfs4_state *state,
1598				     const struct nfs4_state_recovery_ops *ops)
 
1599{
1600	struct nfs4_lock_state *lock;
1601	int status;
1602
1603	status = ops->recover_open(sp, state);
1604	if (status < 0)
1605		return status;
1606
1607	status = nfs4_reclaim_locks(state, ops);
1608	if (status < 0)
1609		return status;
1610
1611	if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) {
1612		spin_lock(&state->state_lock);
1613		list_for_each_entry(lock, &state->lock_states, ls_locks) {
1614			trace_nfs4_state_lock_reclaim(state, lock);
1615			if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
1616				pr_warn_ratelimited("NFS: %s: Lock reclaim failed!\n", __func__);
 
1617		}
1618		spin_unlock(&state->state_lock);
1619	}
1620
1621	nfs42_complete_copies(sp, state);
1622	clear_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1623	return status;
1624}
1625
1626static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
 
 
1627{
1628	struct nfs4_state *state;
1629	unsigned int loop = 0;
1630	int status = 0;
1631#ifdef CONFIG_NFS_V4_2
1632	bool found_ssc_copy_state = false;
1633#endif /* CONFIG_NFS_V4_2 */
1634
1635	/* Note: we rely on the sp->so_states list being ordered 
1636	 * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1637	 * states first.
1638	 * This is needed to ensure that the server won't give us any
1639	 * read delegations that we have to return if, say, we are
1640	 * recovering after a network partition or a reboot from a
1641	 * server that doesn't support a grace period.
1642	 */
1643	spin_lock(&sp->so_lock);
1644	raw_write_seqcount_begin(&sp->so_reclaim_seqcount);
1645restart:
1646	list_for_each_entry(state, &sp->so_states, open_states) {
1647		if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1648			continue;
1649		if (!nfs4_valid_open_stateid(state))
1650			continue;
1651		if (state->state == 0)
1652			continue;
1653#ifdef CONFIG_NFS_V4_2
1654		if (test_bit(NFS_SRV_SSC_COPY_STATE, &state->flags)) {
1655			nfs4_state_mark_recovery_failed(state, -EIO);
1656			found_ssc_copy_state = true;
1657			continue;
1658		}
1659#endif /* CONFIG_NFS_V4_2 */
1660		refcount_inc(&state->count);
1661		spin_unlock(&sp->so_lock);
1662		status = __nfs4_reclaim_open_state(sp, state, ops);
1663
1664		switch (status) {
1665		default:
1666			if (status >= 0) {
1667				loop = 0;
1668				break;
1669			}
1670			printk(KERN_ERR "NFS: %s: unhandled error %d\n", __func__, status);
1671			fallthrough;
1672		case -ENOENT:
1673		case -ENOMEM:
1674		case -EACCES:
1675		case -EROFS:
1676		case -EIO:
1677		case -ESTALE:
1678			/* Open state on this file cannot be recovered */
1679			nfs4_state_mark_recovery_failed(state, status);
1680			break;
1681		case -EAGAIN:
1682			ssleep(1);
1683			if (loop++ < 10) {
1684				set_bit(ops->state_flag_bit, &state->flags);
1685				break;
1686			}
1687			fallthrough;
1688		case -NFS4ERR_ADMIN_REVOKED:
1689		case -NFS4ERR_STALE_STATEID:
1690		case -NFS4ERR_OLD_STATEID:
1691		case -NFS4ERR_BAD_STATEID:
1692		case -NFS4ERR_RECLAIM_BAD:
1693		case -NFS4ERR_RECLAIM_CONFLICT:
1694			nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1695			break;
1696		case -NFS4ERR_EXPIRED:
1697		case -NFS4ERR_NO_GRACE:
1698			nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1699			fallthrough;
1700		case -NFS4ERR_STALE_CLIENTID:
1701		case -NFS4ERR_BADSESSION:
1702		case -NFS4ERR_BADSLOT:
1703		case -NFS4ERR_BAD_HIGH_SLOT:
1704		case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1705		case -ETIMEDOUT:
1706			goto out_err;
1707		}
1708		nfs4_put_open_state(state);
1709		spin_lock(&sp->so_lock);
1710		goto restart;
1711	}
1712	raw_write_seqcount_end(&sp->so_reclaim_seqcount);
1713	spin_unlock(&sp->so_lock);
1714#ifdef CONFIG_NFS_V4_2
1715	if (found_ssc_copy_state)
1716		return -EIO;
1717#endif /* CONFIG_NFS_V4_2 */
1718	return 0;
1719out_err:
1720	nfs4_put_open_state(state);
1721	spin_lock(&sp->so_lock);
1722	raw_write_seqcount_end(&sp->so_reclaim_seqcount);
1723	spin_unlock(&sp->so_lock);
1724	return status;
1725}
1726
1727static void nfs4_clear_open_state(struct nfs4_state *state)
1728{
1729	struct nfs4_lock_state *lock;
1730
1731	clear_bit(NFS_DELEGATED_STATE, &state->flags);
1732	clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1733	clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1734	clear_bit(NFS_O_RDWR_STATE, &state->flags);
1735	spin_lock(&state->state_lock);
1736	list_for_each_entry(lock, &state->lock_states, ls_locks) {
1737		lock->ls_seqid.flags = 0;
1738		clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags);
1739	}
1740	spin_unlock(&state->state_lock);
1741}
1742
1743static void nfs4_reset_seqids(struct nfs_server *server,
1744	int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1745{
1746	struct nfs_client *clp = server->nfs_client;
1747	struct nfs4_state_owner *sp;
1748	struct rb_node *pos;
1749	struct nfs4_state *state;
1750
1751	spin_lock(&clp->cl_lock);
1752	for (pos = rb_first(&server->state_owners);
1753	     pos != NULL;
1754	     pos = rb_next(pos)) {
1755		sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1756		sp->so_seqid.flags = 0;
1757		spin_lock(&sp->so_lock);
1758		list_for_each_entry(state, &sp->so_states, open_states) {
1759			if (mark_reclaim(clp, state))
1760				nfs4_clear_open_state(state);
1761		}
1762		spin_unlock(&sp->so_lock);
1763	}
1764	spin_unlock(&clp->cl_lock);
1765}
1766
1767static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1768	int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1769{
1770	struct nfs_server *server;
1771
1772	rcu_read_lock();
1773	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1774		nfs4_reset_seqids(server, mark_reclaim);
1775	rcu_read_unlock();
1776}
1777
1778static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1779{
 
1780	/* Mark all delegations for reclaim */
1781	nfs_delegation_mark_reclaim(clp);
1782	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1783}
1784
1785static int nfs4_reclaim_complete(struct nfs_client *clp,
1786				 const struct nfs4_state_recovery_ops *ops,
1787				 const struct cred *cred)
1788{
1789	/* Notify the server we're done reclaiming our state */
1790	if (ops->reclaim_complete)
1791		return ops->reclaim_complete(clp, cred);
1792	return 0;
1793}
1794
1795static void nfs4_clear_reclaim_server(struct nfs_server *server)
1796{
1797	struct nfs_client *clp = server->nfs_client;
1798	struct nfs4_state_owner *sp;
1799	struct rb_node *pos;
1800	struct nfs4_state *state;
1801
1802	spin_lock(&clp->cl_lock);
1803	for (pos = rb_first(&server->state_owners);
1804	     pos != NULL;
1805	     pos = rb_next(pos)) {
1806		sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1807		spin_lock(&sp->so_lock);
1808		list_for_each_entry(state, &sp->so_states, open_states) {
1809			if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1810						&state->flags))
1811				continue;
1812			nfs4_state_mark_reclaim_nograce(clp, state);
1813		}
1814		spin_unlock(&sp->so_lock);
1815	}
1816	spin_unlock(&clp->cl_lock);
1817}
1818
1819static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1820{
1821	struct nfs_server *server;
1822
1823	if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1824		return 0;
1825
1826	rcu_read_lock();
1827	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1828		nfs4_clear_reclaim_server(server);
1829	rcu_read_unlock();
1830
1831	nfs_delegation_reap_unclaimed(clp);
1832	return 1;
1833}
1834
1835static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1836{
1837	const struct nfs4_state_recovery_ops *ops;
1838	const struct cred *cred;
1839	int err;
1840
1841	if (!nfs4_state_clear_reclaim_reboot(clp))
1842		return;
1843	ops = clp->cl_mvops->reboot_recovery_ops;
1844	cred = nfs4_get_clid_cred(clp);
1845	err = nfs4_reclaim_complete(clp, ops, cred);
1846	put_cred(cred);
1847	if (err == -NFS4ERR_CONN_NOT_BOUND_TO_SESSION)
1848		set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1849}
1850
1851static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1852{
1853	nfs_mark_test_expired_all_delegations(clp);
1854	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1855}
1856
1857static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1858{
1859	switch (error) {
1860	case 0:
1861		break;
1862	case -NFS4ERR_CB_PATH_DOWN:
1863		nfs40_handle_cb_pathdown(clp);
1864		break;
1865	case -NFS4ERR_NO_GRACE:
1866		nfs4_state_end_reclaim_reboot(clp);
1867		break;
1868	case -NFS4ERR_STALE_CLIENTID:
1869		set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1870		nfs4_state_start_reclaim_reboot(clp);
1871		break;
1872	case -NFS4ERR_EXPIRED:
1873		set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1874		nfs4_state_start_reclaim_nograce(clp);
1875		break;
1876	case -NFS4ERR_BADSESSION:
1877	case -NFS4ERR_BADSLOT:
1878	case -NFS4ERR_BAD_HIGH_SLOT:
1879	case -NFS4ERR_DEADSESSION:
1880	case -NFS4ERR_SEQ_FALSE_RETRY:
1881	case -NFS4ERR_SEQ_MISORDERED:
1882		set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1883		/* Zero session reset errors */
1884		break;
1885	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1886		set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1887		break;
1888	default:
1889		dprintk("%s: failed to handle error %d for server %s\n",
1890				__func__, error, clp->cl_hostname);
1891		return error;
1892	}
1893	dprintk("%s: handled error %d for server %s\n", __func__, error,
1894			clp->cl_hostname);
1895	return 0;
1896}
1897
1898static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1899{
1900	struct nfs4_state_owner *sp;
1901	struct nfs_server *server;
1902	struct rb_node *pos;
1903	LIST_HEAD(freeme);
1904	int status = 0;
 
1905
1906restart:
1907	rcu_read_lock();
1908	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1909		nfs4_purge_state_owners(server, &freeme);
1910		spin_lock(&clp->cl_lock);
1911		for (pos = rb_first(&server->state_owners);
1912		     pos != NULL;
1913		     pos = rb_next(pos)) {
1914			sp = rb_entry(pos,
1915				struct nfs4_state_owner, so_server_node);
1916			if (!test_and_clear_bit(ops->owner_flag_bit,
1917							&sp->so_flags))
1918				continue;
1919			if (!atomic_inc_not_zero(&sp->so_count))
1920				continue;
1921			spin_unlock(&clp->cl_lock);
1922			rcu_read_unlock();
1923
1924			status = nfs4_reclaim_open_state(sp, ops);
1925			if (status < 0) {
 
 
 
1926				set_bit(ops->owner_flag_bit, &sp->so_flags);
1927				nfs4_put_state_owner(sp);
1928				status = nfs4_recovery_handle_error(clp, status);
1929				return (status != 0) ? status : -EAGAIN;
1930			}
1931
1932			nfs4_put_state_owner(sp);
1933			goto restart;
1934		}
1935		spin_unlock(&clp->cl_lock);
1936	}
1937	rcu_read_unlock();
1938	nfs4_free_state_owners(&freeme);
 
 
 
1939	return 0;
1940}
1941
1942static int nfs4_check_lease(struct nfs_client *clp)
1943{
1944	const struct cred *cred;
1945	const struct nfs4_state_maintenance_ops *ops =
1946		clp->cl_mvops->state_renewal_ops;
1947	int status;
1948
1949	/* Is the client already known to have an expired lease? */
1950	if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1951		return 0;
1952	cred = ops->get_state_renewal_cred(clp);
1953	if (cred == NULL) {
1954		cred = nfs4_get_clid_cred(clp);
1955		status = -ENOKEY;
1956		if (cred == NULL)
1957			goto out;
1958	}
1959	status = ops->renew_lease(clp, cred);
1960	put_cred(cred);
1961	if (status == -ETIMEDOUT) {
1962		set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1963		return 0;
1964	}
1965out:
1966	return nfs4_recovery_handle_error(clp, status);
1967}
1968
1969/* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors
1970 * and for recoverable errors on EXCHANGE_ID for v4.1
1971 */
1972static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
1973{
1974	switch (status) {
1975	case -NFS4ERR_SEQ_MISORDERED:
1976		if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
1977			return -ESERVERFAULT;
1978		/* Lease confirmation error: retry after purging the lease */
1979		ssleep(1);
1980		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1981		break;
1982	case -NFS4ERR_STALE_CLIENTID:
1983		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1984		nfs4_state_start_reclaim_reboot(clp);
1985		break;
1986	case -NFS4ERR_CLID_INUSE:
1987		pr_err("NFS: Server %s reports our clientid is in use\n",
1988			clp->cl_hostname);
1989		nfs_mark_client_ready(clp, -EPERM);
1990		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1991		return -EPERM;
1992	case -EACCES:
1993	case -NFS4ERR_DELAY:
1994	case -EAGAIN:
1995		ssleep(1);
1996		break;
1997
1998	case -NFS4ERR_MINOR_VERS_MISMATCH:
1999		if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
2000			nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
2001		dprintk("%s: exit with error %d for server %s\n",
2002				__func__, -EPROTONOSUPPORT, clp->cl_hostname);
2003		return -EPROTONOSUPPORT;
 
 
 
 
2004	case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
2005				 * in nfs4_exchange_id */
2006	default:
2007		dprintk("%s: exit with error %d for server %s\n", __func__,
2008				status, clp->cl_hostname);
2009		return status;
2010	}
2011	set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
2012	dprintk("%s: handled error %d for server %s\n", __func__, status,
2013			clp->cl_hostname);
2014	return 0;
2015}
2016
2017static int nfs4_establish_lease(struct nfs_client *clp)
2018{
2019	const struct cred *cred;
2020	const struct nfs4_state_recovery_ops *ops =
2021		clp->cl_mvops->reboot_recovery_ops;
2022	int status;
2023
2024	status = nfs4_begin_drain_session(clp);
2025	if (status != 0)
2026		return status;
2027	cred = nfs4_get_clid_cred(clp);
2028	if (cred == NULL)
2029		return -ENOENT;
2030	status = ops->establish_clid(clp, cred);
2031	put_cred(cred);
2032	if (status != 0)
2033		return status;
2034	pnfs_destroy_all_layouts(clp);
2035	return 0;
2036}
2037
2038/*
2039 * Returns zero or a negative errno.  NFS4ERR values are converted
2040 * to local errno values.
2041 */
2042static int nfs4_reclaim_lease(struct nfs_client *clp)
2043{
2044	int status;
2045
2046	status = nfs4_establish_lease(clp);
2047	if (status < 0)
2048		return nfs4_handle_reclaim_lease_error(clp, status);
2049	if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state))
2050		nfs4_state_start_reclaim_nograce(clp);
2051	if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
2052		set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
2053	clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
2054	clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
2055	return 0;
2056}
2057
2058static int nfs4_purge_lease(struct nfs_client *clp)
2059{
2060	int status;
2061
2062	status = nfs4_establish_lease(clp);
2063	if (status < 0)
2064		return nfs4_handle_reclaim_lease_error(clp, status);
2065	clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
2066	set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
2067	nfs4_state_start_reclaim_nograce(clp);
2068	return 0;
2069}
2070
2071/*
2072 * Try remote migration of one FSID from a source server to a
2073 * destination server.  The source server provides a list of
2074 * potential destinations.
2075 *
2076 * Returns zero or a negative NFS4ERR status code.
2077 */
2078static int nfs4_try_migration(struct nfs_server *server, const struct cred *cred)
2079{
2080	struct nfs_client *clp = server->nfs_client;
2081	struct nfs4_fs_locations *locations = NULL;
2082	struct inode *inode;
2083	struct page *page;
2084	int status, result;
2085
2086	dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__,
2087			(unsigned long long)server->fsid.major,
2088			(unsigned long long)server->fsid.minor,
2089			clp->cl_hostname);
2090
2091	result = 0;
2092	page = alloc_page(GFP_KERNEL);
2093	locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
2094	if (page == NULL || locations == NULL) {
2095		dprintk("<-- %s: no memory\n", __func__);
2096		goto out;
2097	}
 
 
 
 
 
2098
2099	inode = d_inode(server->super->s_root);
2100	result = nfs4_proc_get_locations(inode, locations, page, cred);
 
2101	if (result) {
2102		dprintk("<-- %s: failed to retrieve fs_locations: %d\n",
2103			__func__, result);
2104		goto out;
2105	}
2106
2107	result = -NFS4ERR_NXIO;
2108	if (!(locations->fattr.valid & NFS_ATTR_FATTR_V4_LOCATIONS)) {
 
 
 
2109		dprintk("<-- %s: No fs_locations data, migration skipped\n",
2110			__func__);
2111		goto out;
2112	}
2113
2114	status = nfs4_begin_drain_session(clp);
2115	if (status != 0) {
2116		result = status;
2117		goto out;
2118	}
2119
2120	status = nfs4_replace_transport(server, locations);
2121	if (status != 0) {
2122		dprintk("<-- %s: failed to replace transport: %d\n",
2123			__func__, status);
2124		goto out;
2125	}
2126
2127	result = 0;
2128	dprintk("<-- %s: migration succeeded\n", __func__);
2129
2130out:
2131	if (page != NULL)
2132		__free_page(page);
 
 
2133	kfree(locations);
2134	if (result) {
2135		pr_err("NFS: migration recovery failed (server %s)\n",
2136				clp->cl_hostname);
2137		set_bit(NFS_MIG_FAILED, &server->mig_status);
2138	}
2139	return result;
2140}
2141
2142/*
2143 * Returns zero or a negative NFS4ERR status code.
2144 */
2145static int nfs4_handle_migration(struct nfs_client *clp)
2146{
2147	const struct nfs4_state_maintenance_ops *ops =
2148				clp->cl_mvops->state_renewal_ops;
2149	struct nfs_server *server;
2150	const struct cred *cred;
2151
2152	dprintk("%s: migration reported on \"%s\"\n", __func__,
2153			clp->cl_hostname);
2154
2155	cred = ops->get_state_renewal_cred(clp);
2156	if (cred == NULL)
2157		return -NFS4ERR_NOENT;
2158
2159	clp->cl_mig_gen++;
2160restart:
2161	rcu_read_lock();
2162	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
2163		int status;
2164
2165		if (server->mig_gen == clp->cl_mig_gen)
2166			continue;
2167		server->mig_gen = clp->cl_mig_gen;
2168
2169		if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION,
2170						&server->mig_status))
2171			continue;
2172
2173		rcu_read_unlock();
2174		status = nfs4_try_migration(server, cred);
2175		if (status < 0) {
2176			put_cred(cred);
2177			return status;
2178		}
2179		goto restart;
2180	}
2181	rcu_read_unlock();
2182	put_cred(cred);
2183	return 0;
2184}
2185
2186/*
2187 * Test each nfs_server on the clp's cl_superblocks list to see
2188 * if it's moved to another server.  Stop when the server no longer
2189 * returns NFS4ERR_LEASE_MOVED.
2190 */
2191static int nfs4_handle_lease_moved(struct nfs_client *clp)
2192{
2193	const struct nfs4_state_maintenance_ops *ops =
2194				clp->cl_mvops->state_renewal_ops;
2195	struct nfs_server *server;
2196	const struct cred *cred;
2197
2198	dprintk("%s: lease moved reported on \"%s\"\n", __func__,
2199			clp->cl_hostname);
2200
2201	cred = ops->get_state_renewal_cred(clp);
2202	if (cred == NULL)
2203		return -NFS4ERR_NOENT;
2204
2205	clp->cl_mig_gen++;
2206restart:
2207	rcu_read_lock();
2208	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
2209		struct inode *inode;
2210		int status;
2211
2212		if (server->mig_gen == clp->cl_mig_gen)
2213			continue;
2214		server->mig_gen = clp->cl_mig_gen;
2215
2216		rcu_read_unlock();
2217
2218		inode = d_inode(server->super->s_root);
2219		status = nfs4_proc_fsid_present(inode, cred);
2220		if (status != -NFS4ERR_MOVED)
2221			goto restart;	/* wasn't this one */
2222		if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED)
2223			goto restart;	/* there are more */
2224		goto out;
2225	}
2226	rcu_read_unlock();
2227
2228out:
2229	put_cred(cred);
2230	return 0;
2231}
2232
2233/**
2234 * nfs4_discover_server_trunking - Detect server IP address trunking
2235 *
2236 * @clp: nfs_client under test
2237 * @result: OUT: found nfs_client, or clp
2238 *
2239 * Returns zero or a negative errno.  If zero is returned,
2240 * an nfs_client pointer is planted in "result".
2241 *
2242 * Note: since we are invoked in process context, and
2243 * not from inside the state manager, we cannot use
2244 * nfs4_handle_reclaim_lease_error().
2245 */
2246int nfs4_discover_server_trunking(struct nfs_client *clp,
2247				  struct nfs_client **result)
2248{
2249	const struct nfs4_state_recovery_ops *ops =
2250				clp->cl_mvops->reboot_recovery_ops;
2251	struct rpc_clnt *clnt;
2252	const struct cred *cred;
2253	int i, status;
2254
2255	dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
2256
2257	clnt = clp->cl_rpcclient;
2258	i = 0;
2259
2260	mutex_lock(&nfs_clid_init_mutex);
2261again:
2262	status  = -ENOENT;
2263	cred = nfs4_get_clid_cred(clp);
2264	if (cred == NULL)
2265		goto out_unlock;
2266
2267	status = ops->detect_trunking(clp, result, cred);
2268	put_cred(cred);
2269	switch (status) {
2270	case 0:
2271	case -EINTR:
2272	case -ERESTARTSYS:
2273		break;
2274	case -ETIMEDOUT:
2275		if (clnt->cl_softrtry)
2276			break;
2277		fallthrough;
2278	case -NFS4ERR_DELAY:
2279	case -EAGAIN:
2280		ssleep(1);
2281		fallthrough;
2282	case -NFS4ERR_STALE_CLIENTID:
2283		dprintk("NFS: %s after status %d, retrying\n",
2284			__func__, status);
2285		goto again;
2286	case -EACCES:
2287		if (i++ == 0) {
2288			nfs4_root_machine_cred(clp);
2289			goto again;
2290		}
2291		if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX)
2292			break;
2293		fallthrough;
2294	case -NFS4ERR_CLID_INUSE:
2295	case -NFS4ERR_WRONGSEC:
2296		/* No point in retrying if we already used RPC_AUTH_UNIX */
2297		if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) {
2298			status = -EPERM;
2299			break;
2300		}
2301		clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
2302		if (IS_ERR(clnt)) {
2303			status = PTR_ERR(clnt);
2304			break;
2305		}
2306		/* Note: this is safe because we haven't yet marked the
2307		 * client as ready, so we are the only user of
2308		 * clp->cl_rpcclient
2309		 */
2310		clnt = xchg(&clp->cl_rpcclient, clnt);
2311		rpc_shutdown_client(clnt);
2312		clnt = clp->cl_rpcclient;
2313		goto again;
2314
2315	case -NFS4ERR_MINOR_VERS_MISMATCH:
2316		status = -EPROTONOSUPPORT;
2317		break;
2318
2319	case -EKEYEXPIRED:
2320	case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
2321				 * in nfs4_exchange_id */
2322		status = -EKEYEXPIRED;
2323		break;
2324	default:
2325		pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
2326				__func__, status);
2327		status = -EIO;
2328	}
2329
2330out_unlock:
2331	mutex_unlock(&nfs_clid_init_mutex);
2332	dprintk("NFS: %s: status = %d\n", __func__, status);
2333	return status;
2334}
2335
2336#ifdef CONFIG_NFS_V4_1
2337void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
2338{
2339	struct nfs_client *clp = session->clp;
2340
2341	switch (err) {
2342	default:
2343		set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2344		break;
2345	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
2346		set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2347	}
2348	nfs4_schedule_state_manager(clp);
2349}
2350EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
2351
2352void nfs41_notify_server(struct nfs_client *clp)
2353{
2354	/* Use CHECK_LEASE to ping the server with a SEQUENCE */
2355	set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
2356	nfs4_schedule_state_manager(clp);
2357}
2358
2359static void nfs4_reset_all_state(struct nfs_client *clp)
2360{
2361	if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
2362		set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
2363		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
2364		nfs4_state_start_reclaim_nograce(clp);
2365		dprintk("%s: scheduling reset of all state for server %s!\n",
2366				__func__, clp->cl_hostname);
2367		nfs4_schedule_state_manager(clp);
2368	}
2369}
2370
2371static void nfs41_handle_server_reboot(struct nfs_client *clp)
2372{
2373	if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
2374		nfs4_state_start_reclaim_reboot(clp);
2375		dprintk("%s: server %s rebooted!\n", __func__,
2376				clp->cl_hostname);
2377		nfs4_schedule_state_manager(clp);
2378	}
2379}
2380
2381static void nfs41_handle_all_state_revoked(struct nfs_client *clp)
2382{
2383	nfs4_reset_all_state(clp);
2384	dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
2385}
2386
2387static void nfs41_handle_some_state_revoked(struct nfs_client *clp)
2388{
2389	nfs4_state_start_reclaim_nograce(clp);
2390	nfs4_schedule_state_manager(clp);
2391
2392	dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
2393}
2394
2395static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
2396{
2397	/* FIXME: For now, we destroy all layouts. */
2398	pnfs_destroy_all_layouts(clp);
2399	nfs_test_expired_all_delegations(clp);
2400	dprintk("%s: Recallable state revoked on server %s!\n", __func__,
2401			clp->cl_hostname);
2402}
2403
2404static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
2405{
2406	set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2407	nfs4_schedule_state_manager(clp);
2408
2409	dprintk("%s: server %s declared a backchannel fault\n", __func__,
2410			clp->cl_hostname);
2411}
2412
2413static void nfs41_handle_cb_path_down(struct nfs_client *clp)
2414{
2415	if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2416		&clp->cl_state) == 0)
2417		nfs4_schedule_state_manager(clp);
2418}
2419
2420void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags,
2421		bool recovery)
2422{
2423	if (!flags)
2424		return;
2425
2426	dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
2427		__func__, clp->cl_hostname, clp->cl_clientid, flags);
2428	/*
2429	 * If we're called from the state manager thread, then assume we're
2430	 * already handling the RECLAIM_NEEDED and/or STATE_REVOKED.
2431	 * Those flags are expected to remain set until we're done
2432	 * recovering (see RFC5661, section 18.46.3).
2433	 */
2434	if (recovery)
2435		goto out_recovery;
2436
2437	if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
2438		nfs41_handle_server_reboot(clp);
2439	if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED))
2440		nfs41_handle_all_state_revoked(clp);
2441	if (flags & (SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
2442			    SEQ4_STATUS_ADMIN_STATE_REVOKED))
2443		nfs41_handle_some_state_revoked(clp);
2444	if (flags & SEQ4_STATUS_LEASE_MOVED)
2445		nfs4_schedule_lease_moved_recovery(clp);
2446	if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
2447		nfs41_handle_recallable_state_revoked(clp);
2448out_recovery:
2449	if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
2450		nfs41_handle_backchannel_fault(clp);
2451	else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
2452				SEQ4_STATUS_CB_PATH_DOWN_SESSION))
2453		nfs41_handle_cb_path_down(clp);
2454}
2455
2456static int nfs4_reset_session(struct nfs_client *clp)
2457{
2458	const struct cred *cred;
2459	int status;
2460
2461	if (!nfs4_has_session(clp))
2462		return 0;
2463	status = nfs4_begin_drain_session(clp);
2464	if (status != 0)
2465		return status;
2466	cred = nfs4_get_clid_cred(clp);
2467	status = nfs4_proc_destroy_session(clp->cl_session, cred);
2468	switch (status) {
2469	case 0:
2470	case -NFS4ERR_BADSESSION:
2471	case -NFS4ERR_DEADSESSION:
2472		break;
2473	case -NFS4ERR_BACK_CHAN_BUSY:
2474	case -NFS4ERR_DELAY:
2475		set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2476		status = 0;
2477		ssleep(1);
2478		goto out;
2479	default:
2480		status = nfs4_recovery_handle_error(clp, status);
2481		goto out;
2482	}
2483
2484	memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
2485	status = nfs4_proc_create_session(clp, cred);
2486	if (status) {
2487		dprintk("%s: session reset failed with status %d for server %s!\n",
2488			__func__, status, clp->cl_hostname);
2489		status = nfs4_handle_reclaim_lease_error(clp, status);
2490		goto out;
2491	}
2492	nfs41_finish_session_reset(clp);
2493	dprintk("%s: session reset was successful for server %s!\n",
2494			__func__, clp->cl_hostname);
2495out:
2496	put_cred(cred);
2497	return status;
2498}
2499
2500static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2501{
2502	const struct cred *cred;
2503	int ret;
2504
2505	if (!nfs4_has_session(clp))
2506		return 0;
2507	ret = nfs4_begin_drain_session(clp);
2508	if (ret != 0)
2509		return ret;
2510	cred = nfs4_get_clid_cred(clp);
2511	ret = nfs4_proc_bind_conn_to_session(clp, cred);
2512	put_cred(cred);
2513	clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2514	switch (ret) {
2515	case 0:
2516		dprintk("%s: bind_conn_to_session was successful for server %s!\n",
2517			__func__, clp->cl_hostname);
2518		break;
2519	case -NFS4ERR_DELAY:
2520		ssleep(1);
2521		set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2522		break;
2523	default:
2524		return nfs4_recovery_handle_error(clp, ret);
2525	}
2526	return 0;
2527}
2528
2529static void nfs4_layoutreturn_any_run(struct nfs_client *clp)
2530{
2531	int iomode = 0;
2532
2533	if (test_and_clear_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &clp->cl_state))
2534		iomode += IOMODE_READ;
2535	if (test_and_clear_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &clp->cl_state))
2536		iomode += IOMODE_RW;
2537	/* Note: IOMODE_READ + IOMODE_RW == IOMODE_ANY */
2538	if (iomode) {
2539		pnfs_layout_return_unused_byclid(clp, iomode);
2540		set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
2541	}
2542}
2543#else /* CONFIG_NFS_V4_1 */
2544static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
2545
2546static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2547{
2548	return 0;
2549}
2550
2551static void nfs4_layoutreturn_any_run(struct nfs_client *clp)
2552{
2553}
2554#endif /* CONFIG_NFS_V4_1 */
2555
2556static void nfs4_state_manager(struct nfs_client *clp)
2557{
 
2558	int status = 0;
2559	const char *section = "", *section_sep = "";
2560
 
 
 
 
 
 
 
2561	/* Ensure exclusive access to NFSv4 state */
2562	do {
2563		trace_nfs4_state_mgr(clp);
2564		clear_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
2565		if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
2566			section = "purge state";
2567			status = nfs4_purge_lease(clp);
2568			if (status < 0)
2569				goto out_error;
2570			continue;
2571		}
2572
2573		if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
2574			section = "lease expired";
2575			/* We're going to have to re-establish a clientid */
2576			status = nfs4_reclaim_lease(clp);
2577			if (status < 0)
2578				goto out_error;
2579			continue;
2580		}
2581
2582		/* Initialize or reset the session */
2583		if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) {
2584			section = "reset session";
2585			status = nfs4_reset_session(clp);
2586			if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
2587				continue;
2588			if (status < 0)
2589				goto out_error;
2590		}
2591
2592		/* Send BIND_CONN_TO_SESSION */
2593		if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2594				&clp->cl_state)) {
2595			section = "bind conn to session";
2596			status = nfs4_bind_conn_to_session(clp);
2597			if (status < 0)
2598				goto out_error;
2599			continue;
2600		}
2601
2602		if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
2603			section = "check lease";
2604			status = nfs4_check_lease(clp);
2605			if (status < 0)
2606				goto out_error;
2607			continue;
2608		}
2609
2610		if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) {
2611			section = "migration";
2612			status = nfs4_handle_migration(clp);
2613			if (status < 0)
2614				goto out_error;
2615		}
2616
2617		if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) {
2618			section = "lease moved";
2619			status = nfs4_handle_lease_moved(clp);
2620			if (status < 0)
2621				goto out_error;
2622		}
2623
2624		/* First recover reboot state... */
2625		if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
2626			section = "reclaim reboot";
2627			status = nfs4_do_reclaim(clp,
2628				clp->cl_mvops->reboot_recovery_ops);
2629			if (status == -EAGAIN)
2630				continue;
2631			if (status < 0)
2632				goto out_error;
2633			nfs4_state_end_reclaim_reboot(clp);
 
2634		}
2635
2636		/* Detect expired delegations... */
2637		if (test_and_clear_bit(NFS4CLNT_DELEGATION_EXPIRED, &clp->cl_state)) {
2638			section = "detect expired delegations";
2639			nfs_reap_expired_delegations(clp);
2640			continue;
2641		}
2642
2643		/* Now recover expired state... */
2644		if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
2645			section = "reclaim nograce";
2646			status = nfs4_do_reclaim(clp,
2647				clp->cl_mvops->nograce_recovery_ops);
2648			if (status == -EAGAIN)
2649				continue;
2650			if (status < 0)
2651				goto out_error;
2652			clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
2653		}
2654
 
2655		nfs4_end_drain_session(clp);
2656		nfs4_clear_state_manager_bit(clp);
2657
 
 
 
 
 
 
 
2658		if (!test_and_set_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state)) {
2659			if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
2660				nfs_client_return_marked_delegations(clp);
2661				set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
2662			}
2663			nfs4_layoutreturn_any_run(clp);
2664			clear_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state);
2665		}
2666
2667		/* Did we race with an attempt to give us more work? */
2668		if (!test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state))
2669			return;
2670		if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
2671			return;
2672	} while (refcount_read(&clp->cl_count) > 1 && !signalled());
2673	goto out_drain;
2674
2675out_error:
2676	if (strlen(section))
2677		section_sep = ": ";
2678	trace_nfs4_state_mgr_failed(clp, section, status);
2679	pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s"
2680			" with error %d\n", section_sep, section,
2681			clp->cl_hostname, -status);
2682	ssleep(1);
2683out_drain:
 
2684	nfs4_end_drain_session(clp);
2685	nfs4_clear_state_manager_bit(clp);
2686}
2687
2688static int nfs4_run_state_manager(void *ptr)
2689{
2690	struct nfs_client *clp = ptr;
 
 
 
 
2691
2692	allow_signal(SIGKILL);
 
2693	nfs4_state_manager(clp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2694	nfs_put_client(clp);
2695	module_put_and_exit(0);
2696	return 0;
2697}
v6.8
   1/*
   2 *  fs/nfs/nfs4state.c
   3 *
   4 *  Client-side XDR for NFSv4.
   5 *
   6 *  Copyright (c) 2002 The Regents of the University of Michigan.
   7 *  All rights reserved.
   8 *
   9 *  Kendrick Smith <kmsmith@umich.edu>
  10 *
  11 *  Redistribution and use in source and binary forms, with or without
  12 *  modification, are permitted provided that the following conditions
  13 *  are met:
  14 *
  15 *  1. Redistributions of source code must retain the above copyright
  16 *     notice, this list of conditions and the following disclaimer.
  17 *  2. Redistributions in binary form must reproduce the above copyright
  18 *     notice, this list of conditions and the following disclaimer in the
  19 *     documentation and/or other materials provided with the distribution.
  20 *  3. Neither the name of the University nor the names of its
  21 *     contributors may be used to endorse or promote products derived
  22 *     from this software without specific prior written permission.
  23 *
  24 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  25 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  26 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  27 *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  31 *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35 *
  36 * Implementation of the NFSv4 state model.  For the time being,
  37 * this is minimal, but will be made much more complex in a
  38 * subsequent patch.
  39 */
  40
  41#include <linux/kernel.h>
  42#include <linux/slab.h>
  43#include <linux/fs.h>
  44#include <linux/nfs_fs.h>
  45#include <linux/kthread.h>
  46#include <linux/module.h>
  47#include <linux/random.h>
  48#include <linux/ratelimit.h>
  49#include <linux/workqueue.h>
  50#include <linux/bitops.h>
  51#include <linux/jiffies.h>
  52#include <linux/sched/mm.h>
  53
  54#include <linux/sunrpc/clnt.h>
  55
  56#include "nfs4_fs.h"
  57#include "callback.h"
  58#include "delegation.h"
  59#include "internal.h"
  60#include "nfs4idmap.h"
  61#include "nfs4session.h"
  62#include "pnfs.h"
  63#include "netns.h"
  64#include "nfs4trace.h"
  65
  66#define NFSDBG_FACILITY		NFSDBG_STATE
  67
  68#define OPENOWNER_POOL_SIZE	8
  69
  70static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp);
  71
  72const nfs4_stateid zero_stateid = {
  73	{ .data = { 0 } },
  74	.type = NFS4_SPECIAL_STATEID_TYPE,
  75};
  76const nfs4_stateid invalid_stateid = {
  77	{
  78		/* Funky initialiser keeps older gcc versions happy */
  79		.data = { 0xff, 0xff, 0xff, 0xff, 0 },
  80	},
  81	.type = NFS4_INVALID_STATEID_TYPE,
  82};
  83
  84const nfs4_stateid current_stateid = {
  85	{
  86		/* Funky initialiser keeps older gcc versions happy */
  87		.data = { 0x0, 0x0, 0x0, 0x1, 0 },
  88	},
  89	.type = NFS4_SPECIAL_STATEID_TYPE,
  90};
  91
  92static DEFINE_MUTEX(nfs_clid_init_mutex);
  93
  94static int nfs4_setup_state_renewal(struct nfs_client *clp)
  95{
  96	int status;
  97	struct nfs_fsinfo fsinfo;
  98
  99	if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
 100		nfs4_schedule_state_renewal(clp);
 101		return 0;
 102	}
 103
 104	status = nfs4_proc_get_lease_time(clp, &fsinfo);
 105	if (status == 0) {
 106		nfs4_set_lease_period(clp, fsinfo.lease_time * HZ);
 107		nfs4_schedule_state_renewal(clp);
 108	}
 109
 110	return status;
 111}
 112
 113int nfs4_init_clientid(struct nfs_client *clp, const struct cred *cred)
 114{
 115	struct nfs4_setclientid_res clid = {
 116		.clientid = clp->cl_clientid,
 117		.confirm = clp->cl_confirm,
 118	};
 119	unsigned short port;
 120	int status;
 121	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 122
 123	if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 124		goto do_confirm;
 125	port = nn->nfs_callback_tcpport;
 126	if (clp->cl_addr.ss_family == AF_INET6)
 127		port = nn->nfs_callback_tcpport6;
 128
 129	status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
 130	if (status != 0)
 131		goto out;
 132	clp->cl_clientid = clid.clientid;
 133	clp->cl_confirm = clid.confirm;
 134	set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 135do_confirm:
 136	status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
 137	if (status != 0)
 138		goto out;
 139	clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 140	nfs4_setup_state_renewal(clp);
 141out:
 142	return status;
 143}
 144
 145/**
 146 * nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
 147 *
 148 * @clp: nfs_client under test
 149 * @result: OUT: found nfs_client, or clp
 150 * @cred: credential to use for trunking test
 151 *
 152 * Returns zero, a negative errno, or a negative NFS4ERR status.
 153 * If zero is returned, an nfs_client pointer is planted in
 154 * "result".
 155 *
 156 * Note: The returned client may not yet be marked ready.
 157 */
 158int nfs40_discover_server_trunking(struct nfs_client *clp,
 159				   struct nfs_client **result,
 160				   const struct cred *cred)
 161{
 162	struct nfs4_setclientid_res clid = {
 163		.clientid = clp->cl_clientid,
 164		.confirm = clp->cl_confirm,
 165	};
 166	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 167	unsigned short port;
 168	int status;
 169
 170	port = nn->nfs_callback_tcpport;
 171	if (clp->cl_addr.ss_family == AF_INET6)
 172		port = nn->nfs_callback_tcpport6;
 173
 174	status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
 175	if (status != 0)
 176		goto out;
 177	clp->cl_clientid = clid.clientid;
 178	clp->cl_confirm = clid.confirm;
 179
 180	status = nfs40_walk_client_list(clp, result, cred);
 181	if (status == 0) {
 182		/* Sustain the lease, even if it's empty.  If the clientid4
 183		 * goes stale it's of no use for trunking discovery. */
 184		nfs4_schedule_state_renewal(*result);
 185
 186		/* If the client state need to recover, do it. */
 187		if (clp->cl_state)
 188			nfs4_schedule_state_manager(clp);
 189	}
 190out:
 191	return status;
 192}
 193
 194const struct cred *nfs4_get_machine_cred(struct nfs_client *clp)
 195{
 196	return get_cred(rpc_machine_cred());
 197}
 198
 199static void nfs4_root_machine_cred(struct nfs_client *clp)
 200{
 201
 202	/* Force root creds instead of machine */
 203	clp->cl_principal = NULL;
 204	clp->cl_rpcclient->cl_principal = NULL;
 205}
 206
 207static const struct cred *
 208nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 209{
 210	const struct cred *cred = NULL;
 211	struct nfs4_state_owner *sp;
 212	struct rb_node *pos;
 213
 214	for (pos = rb_first(&server->state_owners);
 215	     pos != NULL;
 216	     pos = rb_next(pos)) {
 217		sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 218		if (list_empty(&sp->so_states))
 219			continue;
 220		cred = get_cred(sp->so_cred);
 221		break;
 222	}
 223	return cred;
 224}
 225
 226/**
 227 * nfs4_get_renew_cred - Acquire credential for a renew operation
 228 * @clp: client state handle
 229 *
 230 * Returns an rpc_cred with reference count bumped, or NULL.
 231 * Caller must hold clp->cl_lock.
 232 */
 233const struct cred *nfs4_get_renew_cred(struct nfs_client *clp)
 234{
 235	const struct cred *cred = NULL;
 236	struct nfs_server *server;
 237
 238	/* Use machine credentials if available */
 239	cred = nfs4_get_machine_cred(clp);
 240	if (cred != NULL)
 241		goto out;
 242
 243	spin_lock(&clp->cl_lock);
 244	rcu_read_lock();
 245	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 246		cred = nfs4_get_renew_cred_server_locked(server);
 247		if (cred != NULL)
 248			break;
 249	}
 250	rcu_read_unlock();
 251	spin_unlock(&clp->cl_lock);
 252
 253out:
 254	return cred;
 255}
 256
 257static void nfs4_end_drain_slot_table(struct nfs4_slot_table *tbl)
 258{
 259	if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
 260		spin_lock(&tbl->slot_tbl_lock);
 261		nfs41_wake_slot_table(tbl);
 262		spin_unlock(&tbl->slot_tbl_lock);
 263	}
 264}
 265
 266static void nfs4_end_drain_session(struct nfs_client *clp)
 267{
 268	struct nfs4_session *ses = clp->cl_session;
 269
 270	if (clp->cl_slot_tbl) {
 271		nfs4_end_drain_slot_table(clp->cl_slot_tbl);
 272		return;
 273	}
 274
 275	if (ses != NULL) {
 276		nfs4_end_drain_slot_table(&ses->bc_slot_table);
 277		nfs4_end_drain_slot_table(&ses->fc_slot_table);
 278	}
 279}
 280
 281static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
 282{
 283	set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
 284	spin_lock(&tbl->slot_tbl_lock);
 285	if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
 286		reinit_completion(&tbl->complete);
 287		spin_unlock(&tbl->slot_tbl_lock);
 288		return wait_for_completion_interruptible(&tbl->complete);
 289	}
 290	spin_unlock(&tbl->slot_tbl_lock);
 291	return 0;
 292}
 293
 294static int nfs4_begin_drain_session(struct nfs_client *clp)
 295{
 296	struct nfs4_session *ses = clp->cl_session;
 297	int ret;
 298
 299	if (clp->cl_slot_tbl)
 300		return nfs4_drain_slot_tbl(clp->cl_slot_tbl);
 301
 302	/* back channel */
 303	ret = nfs4_drain_slot_tbl(&ses->bc_slot_table);
 304	if (ret)
 305		return ret;
 306	/* fore channel */
 307	return nfs4_drain_slot_tbl(&ses->fc_slot_table);
 308}
 309
 310#if defined(CONFIG_NFS_V4_1)
 311
 312static void nfs41_finish_session_reset(struct nfs_client *clp)
 313{
 314	clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 315	clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
 316	/* create_session negotiated new slot table */
 317	clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
 318	nfs4_setup_state_renewal(clp);
 319}
 320
 321int nfs41_init_clientid(struct nfs_client *clp, const struct cred *cred)
 322{
 323	int status;
 324
 325	if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 326		goto do_confirm;
 327	status = nfs4_proc_exchange_id(clp, cred);
 328	if (status != 0)
 329		goto out;
 330	set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 331do_confirm:
 332	status = nfs4_proc_create_session(clp, cred);
 333	if (status != 0)
 334		goto out;
 335	if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R))
 336		nfs4_state_start_reclaim_reboot(clp);
 337	nfs41_finish_session_reset(clp);
 338	nfs_mark_client_ready(clp, NFS_CS_READY);
 339out:
 340	return status;
 341}
 342
 343/**
 344 * nfs41_discover_server_trunking - Detect server IP address trunking (mv1)
 345 *
 346 * @clp: nfs_client under test
 347 * @result: OUT: found nfs_client, or clp
 348 * @cred: credential to use for trunking test
 349 *
 350 * Returns NFS4_OK, a negative errno, or a negative NFS4ERR status.
 351 * If NFS4_OK is returned, an nfs_client pointer is planted in
 352 * "result".
 353 *
 354 * Note: The returned client may not yet be marked ready.
 355 */
 356int nfs41_discover_server_trunking(struct nfs_client *clp,
 357				   struct nfs_client **result,
 358				   const struct cred *cred)
 359{
 360	int status;
 361
 362	status = nfs4_proc_exchange_id(clp, cred);
 363	if (status != NFS4_OK)
 364		return status;
 365
 366	status = nfs41_walk_client_list(clp, result, cred);
 367	if (status < 0)
 368		return status;
 369	if (clp != *result)
 370		return 0;
 371
 372	/*
 373	 * Purge state if the client id was established in a prior
 374	 * instance and the client id could not have arrived on the
 375	 * server via Transparent State Migration.
 376	 */
 377	if (clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R) {
 378		if (!test_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags))
 379			set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
 380		else
 381			set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 382	}
 383	nfs4_schedule_state_manager(clp);
 384	status = nfs_wait_client_init_complete(clp);
 385	if (status < 0)
 386		nfs_put_client(clp);
 387	return status;
 388}
 389
 390#endif /* CONFIG_NFS_V4_1 */
 391
 392/**
 393 * nfs4_get_clid_cred - Acquire credential for a setclientid operation
 394 * @clp: client state handle
 395 *
 396 * Returns a cred with reference count bumped, or NULL.
 397 */
 398const struct cred *nfs4_get_clid_cred(struct nfs_client *clp)
 399{
 400	const struct cred *cred;
 401
 402	cred = nfs4_get_machine_cred(clp);
 403	return cred;
 404}
 405
 406static struct nfs4_state_owner *
 407nfs4_find_state_owner_locked(struct nfs_server *server, const struct cred *cred)
 408{
 409	struct rb_node **p = &server->state_owners.rb_node,
 410		       *parent = NULL;
 411	struct nfs4_state_owner *sp;
 412	int cmp;
 413
 414	while (*p != NULL) {
 415		parent = *p;
 416		sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 417		cmp = cred_fscmp(cred, sp->so_cred);
 418
 419		if (cmp < 0)
 420			p = &parent->rb_left;
 421		else if (cmp > 0)
 422			p = &parent->rb_right;
 423		else {
 424			if (!list_empty(&sp->so_lru))
 425				list_del_init(&sp->so_lru);
 426			atomic_inc(&sp->so_count);
 427			return sp;
 428		}
 429	}
 430	return NULL;
 431}
 432
 433static struct nfs4_state_owner *
 434nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 435{
 436	struct nfs_server *server = new->so_server;
 437	struct rb_node **p = &server->state_owners.rb_node,
 438		       *parent = NULL;
 439	struct nfs4_state_owner *sp;
 440	int cmp;
 441
 442	while (*p != NULL) {
 443		parent = *p;
 444		sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 445		cmp = cred_fscmp(new->so_cred, sp->so_cred);
 446
 447		if (cmp < 0)
 448			p = &parent->rb_left;
 449		else if (cmp > 0)
 450			p = &parent->rb_right;
 451		else {
 452			if (!list_empty(&sp->so_lru))
 453				list_del_init(&sp->so_lru);
 454			atomic_inc(&sp->so_count);
 455			return sp;
 456		}
 457	}
 458	rb_link_node(&new->so_server_node, parent, p);
 459	rb_insert_color(&new->so_server_node, &server->state_owners);
 460	return new;
 461}
 462
 463static void
 464nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 465{
 466	struct nfs_server *server = sp->so_server;
 467
 468	if (!RB_EMPTY_NODE(&sp->so_server_node))
 469		rb_erase(&sp->so_server_node, &server->state_owners);
 470}
 471
 472static void
 473nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
 474{
 475	sc->create_time = ktime_get();
 476	sc->flags = 0;
 477	sc->counter = 0;
 478	spin_lock_init(&sc->lock);
 479	INIT_LIST_HEAD(&sc->list);
 480	rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
 481}
 482
 483static void
 484nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
 485{
 486	rpc_destroy_wait_queue(&sc->wait);
 487}
 488
 489/*
 490 * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 491 * create a new state_owner.
 492 *
 493 */
 494static struct nfs4_state_owner *
 495nfs4_alloc_state_owner(struct nfs_server *server,
 496		const struct cred *cred,
 497		gfp_t gfp_flags)
 498{
 499	struct nfs4_state_owner *sp;
 500
 501	sp = kzalloc(sizeof(*sp), gfp_flags);
 502	if (!sp)
 503		return NULL;
 504	sp->so_seqid.owner_id = ida_alloc(&server->openowner_id, gfp_flags);
 
 505	if (sp->so_seqid.owner_id < 0) {
 506		kfree(sp);
 507		return NULL;
 508	}
 509	sp->so_server = server;
 510	sp->so_cred = get_cred(cred);
 511	spin_lock_init(&sp->so_lock);
 512	INIT_LIST_HEAD(&sp->so_states);
 513	nfs4_init_seqid_counter(&sp->so_seqid);
 514	atomic_set(&sp->so_count, 1);
 515	INIT_LIST_HEAD(&sp->so_lru);
 516	seqcount_spinlock_init(&sp->so_reclaim_seqcount, &sp->so_lock);
 517	mutex_init(&sp->so_delegreturn_mutex);
 518	return sp;
 519}
 520
 521static void
 522nfs4_reset_state_owner(struct nfs4_state_owner *sp)
 523{
 524	/* This state_owner is no longer usable, but must
 525	 * remain in place so that state recovery can find it
 526	 * and the opens associated with it.
 527	 * It may also be used for new 'open' request to
 528	 * return a delegation to the server.
 529	 * So update the 'create_time' so that it looks like
 530	 * a new state_owner.  This will cause the server to
 531	 * request an OPEN_CONFIRM to start a new sequence.
 532	 */
 533	sp->so_seqid.create_time = ktime_get();
 534}
 535
 536static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 537{
 538	nfs4_destroy_seqid_counter(&sp->so_seqid);
 539	put_cred(sp->so_cred);
 540	ida_free(&sp->so_server->openowner_id, sp->so_seqid.owner_id);
 541	kfree(sp);
 542}
 543
 544static void nfs4_gc_state_owners(struct nfs_server *server)
 545{
 546	struct nfs_client *clp = server->nfs_client;
 547	struct nfs4_state_owner *sp, *tmp;
 548	unsigned long time_min, time_max;
 549	LIST_HEAD(doomed);
 550
 551	spin_lock(&clp->cl_lock);
 552	time_max = jiffies;
 553	time_min = (long)time_max - (long)clp->cl_lease_time;
 554	list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 555		/* NB: LRU is sorted so that oldest is at the head */
 556		if (time_in_range(sp->so_expires, time_min, time_max))
 557			break;
 558		list_move(&sp->so_lru, &doomed);
 559		nfs4_remove_state_owner_locked(sp);
 560	}
 561	spin_unlock(&clp->cl_lock);
 562
 563	list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 564		list_del(&sp->so_lru);
 565		nfs4_free_state_owner(sp);
 566	}
 567}
 568
 569/**
 570 * nfs4_get_state_owner - Look up a state owner given a credential
 571 * @server: nfs_server to search
 572 * @cred: RPC credential to match
 573 * @gfp_flags: allocation mode
 574 *
 575 * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 576 */
 577struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 578					      const struct cred *cred,
 579					      gfp_t gfp_flags)
 580{
 581	struct nfs_client *clp = server->nfs_client;
 582	struct nfs4_state_owner *sp, *new;
 583
 584	spin_lock(&clp->cl_lock);
 585	sp = nfs4_find_state_owner_locked(server, cred);
 586	spin_unlock(&clp->cl_lock);
 587	if (sp != NULL)
 588		goto out;
 589	new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 590	if (new == NULL)
 591		goto out;
 592	spin_lock(&clp->cl_lock);
 593	sp = nfs4_insert_state_owner_locked(new);
 594	spin_unlock(&clp->cl_lock);
 595	if (sp != new)
 596		nfs4_free_state_owner(new);
 597out:
 598	nfs4_gc_state_owners(server);
 599	return sp;
 600}
 601
 602/**
 603 * nfs4_put_state_owner - Release a nfs4_state_owner
 604 * @sp: state owner data to release
 605 *
 606 * Note that we keep released state owners on an LRU
 607 * list.
 608 * This caches valid state owners so that they can be
 609 * reused, to avoid the OPEN_CONFIRM on minor version 0.
 610 * It also pins the uniquifier of dropped state owners for
 611 * a while, to ensure that those state owner names are
 612 * never reused.
 613 */
 614void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 615{
 616	struct nfs_server *server = sp->so_server;
 617	struct nfs_client *clp = server->nfs_client;
 618
 619	if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 620		return;
 621
 622	sp->so_expires = jiffies;
 623	list_add_tail(&sp->so_lru, &server->state_owners_lru);
 624	spin_unlock(&clp->cl_lock);
 625}
 626
 627/**
 628 * nfs4_purge_state_owners - Release all cached state owners
 629 * @server: nfs_server with cached state owners to release
 630 * @head: resulting list of state owners
 631 *
 632 * Called at umount time.  Remaining state owners will be on
 633 * the LRU with ref count of zero.
 634 * Note that the state owners are not freed, but are added
 635 * to the list @head, which can later be used as an argument
 636 * to nfs4_free_state_owners.
 637 */
 638void nfs4_purge_state_owners(struct nfs_server *server, struct list_head *head)
 639{
 640	struct nfs_client *clp = server->nfs_client;
 641	struct nfs4_state_owner *sp, *tmp;
 642
 643	spin_lock(&clp->cl_lock);
 644	list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 645		list_move(&sp->so_lru, head);
 646		nfs4_remove_state_owner_locked(sp);
 647	}
 648	spin_unlock(&clp->cl_lock);
 649}
 650
 651/**
 652 * nfs4_free_state_owners - Release all cached state owners
 653 * @head: resulting list of state owners
 654 *
 655 * Frees a list of state owners that was generated by
 656 * nfs4_purge_state_owners
 657 */
 658void nfs4_free_state_owners(struct list_head *head)
 659{
 660	struct nfs4_state_owner *sp, *tmp;
 661
 662	list_for_each_entry_safe(sp, tmp, head, so_lru) {
 663		list_del(&sp->so_lru);
 664		nfs4_free_state_owner(sp);
 665	}
 666}
 667
 668static struct nfs4_state *
 669nfs4_alloc_open_state(void)
 670{
 671	struct nfs4_state *state;
 672
 673	state = kzalloc(sizeof(*state), GFP_KERNEL_ACCOUNT);
 674	if (!state)
 675		return NULL;
 676	refcount_set(&state->count, 1);
 677	INIT_LIST_HEAD(&state->lock_states);
 678	spin_lock_init(&state->state_lock);
 679	seqlock_init(&state->seqlock);
 680	init_waitqueue_head(&state->waitq);
 681	return state;
 682}
 683
 684void
 685nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 686{
 687	if (state->state == fmode)
 688		return;
 689	/* NB! List reordering - see the reclaim code for why.  */
 690	if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 691		if (fmode & FMODE_WRITE)
 692			list_move(&state->open_states, &state->owner->so_states);
 693		else
 694			list_move_tail(&state->open_states, &state->owner->so_states);
 695	}
 696	state->state = fmode;
 697}
 698
 699static struct nfs4_state *
 700__nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 701{
 702	struct nfs_inode *nfsi = NFS_I(inode);
 703	struct nfs4_state *state;
 704
 705	list_for_each_entry_rcu(state, &nfsi->open_states, inode_states) {
 706		if (state->owner != owner)
 707			continue;
 708		if (!nfs4_valid_open_stateid(state))
 709			continue;
 710		if (refcount_inc_not_zero(&state->count))
 711			return state;
 712	}
 713	return NULL;
 714}
 715
 716static void
 717nfs4_free_open_state(struct nfs4_state *state)
 718{
 719	kfree_rcu(state, rcu_head);
 720}
 721
 722struct nfs4_state *
 723nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 724{
 725	struct nfs4_state *state, *new;
 726	struct nfs_inode *nfsi = NFS_I(inode);
 727
 728	rcu_read_lock();
 729	state = __nfs4_find_state_byowner(inode, owner);
 730	rcu_read_unlock();
 731	if (state)
 732		goto out;
 733	new = nfs4_alloc_open_state();
 734	spin_lock(&owner->so_lock);
 735	spin_lock(&inode->i_lock);
 736	state = __nfs4_find_state_byowner(inode, owner);
 737	if (state == NULL && new != NULL) {
 738		state = new;
 739		state->owner = owner;
 740		atomic_inc(&owner->so_count);
 741		ihold(inode);
 742		state->inode = inode;
 743		list_add_rcu(&state->inode_states, &nfsi->open_states);
 744		spin_unlock(&inode->i_lock);
 745		/* Note: The reclaim code dictates that we add stateless
 746		 * and read-only stateids to the end of the list */
 747		list_add_tail(&state->open_states, &owner->so_states);
 748		spin_unlock(&owner->so_lock);
 749	} else {
 750		spin_unlock(&inode->i_lock);
 751		spin_unlock(&owner->so_lock);
 752		if (new)
 753			nfs4_free_open_state(new);
 754	}
 755out:
 756	return state;
 757}
 758
 759void nfs4_put_open_state(struct nfs4_state *state)
 760{
 761	struct inode *inode = state->inode;
 762	struct nfs4_state_owner *owner = state->owner;
 763
 764	if (!refcount_dec_and_lock(&state->count, &owner->so_lock))
 765		return;
 766	spin_lock(&inode->i_lock);
 767	list_del_rcu(&state->inode_states);
 768	list_del(&state->open_states);
 769	spin_unlock(&inode->i_lock);
 770	spin_unlock(&owner->so_lock);
 771	nfs4_inode_return_delegation_on_close(inode);
 772	iput(inode);
 773	nfs4_free_open_state(state);
 774	nfs4_put_state_owner(owner);
 775}
 776
 777/*
 778 * Close the current file.
 779 */
 780static void __nfs4_close(struct nfs4_state *state,
 781		fmode_t fmode, gfp_t gfp_mask, int wait)
 782{
 783	struct nfs4_state_owner *owner = state->owner;
 784	int call_close = 0;
 785	fmode_t newstate;
 786
 787	atomic_inc(&owner->so_count);
 788	/* Protect against nfs4_find_state() */
 789	spin_lock(&owner->so_lock);
 790	switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 791		case FMODE_READ:
 792			state->n_rdonly--;
 793			break;
 794		case FMODE_WRITE:
 795			state->n_wronly--;
 796			break;
 797		case FMODE_READ|FMODE_WRITE:
 798			state->n_rdwr--;
 799	}
 800	newstate = FMODE_READ|FMODE_WRITE;
 801	if (state->n_rdwr == 0) {
 802		if (state->n_rdonly == 0) {
 803			newstate &= ~FMODE_READ;
 804			call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 805			call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 806		}
 807		if (state->n_wronly == 0) {
 808			newstate &= ~FMODE_WRITE;
 809			call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 810			call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 811		}
 812		if (newstate == 0)
 813			clear_bit(NFS_DELEGATED_STATE, &state->flags);
 814	}
 815	nfs4_state_set_mode_locked(state, newstate);
 816	spin_unlock(&owner->so_lock);
 817
 818	if (!call_close) {
 819		nfs4_put_open_state(state);
 820		nfs4_put_state_owner(owner);
 821	} else
 822		nfs4_do_close(state, gfp_mask, wait);
 823}
 824
 825void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 826{
 827	__nfs4_close(state, fmode, GFP_KERNEL, 0);
 828}
 829
 830void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 831{
 832	__nfs4_close(state, fmode, GFP_KERNEL, 1);
 833}
 834
 835/*
 836 * Search the state->lock_states for an existing lock_owner
 837 * that is compatible with either of the given owners.
 838 * If the second is non-zero, then the first refers to a Posix-lock
 839 * owner (current->files) and the second refers to a flock/OFD
 840 * owner (struct file*).  In that case, prefer a match for the first
 841 * owner.
 842 * If both sorts of locks are held on the one file we cannot know
 843 * which stateid was intended to be used, so a "correct" choice cannot
 844 * be made.  Failing that, a "consistent" choice is preferable.  The
 845 * consistent choice we make is to prefer the first owner, that of a
 846 * Posix lock.
 847 */
 848static struct nfs4_lock_state *
 849__nfs4_find_lock_state(struct nfs4_state *state,
 850		       fl_owner_t fl_owner, fl_owner_t fl_owner2)
 851{
 852	struct nfs4_lock_state *pos, *ret = NULL;
 853	list_for_each_entry(pos, &state->lock_states, ls_locks) {
 854		if (pos->ls_owner == fl_owner) {
 855			ret = pos;
 856			break;
 857		}
 858		if (pos->ls_owner == fl_owner2)
 859			ret = pos;
 860	}
 861	if (ret)
 862		refcount_inc(&ret->ls_count);
 863	return ret;
 864}
 865
 866/*
 867 * Return a compatible lock_state. If no initialized lock_state structure
 868 * exists, return an uninitialized one.
 869 *
 870 */
 871static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 872{
 873	struct nfs4_lock_state *lsp;
 874	struct nfs_server *server = state->owner->so_server;
 875
 876	lsp = kzalloc(sizeof(*lsp), GFP_KERNEL_ACCOUNT);
 877	if (lsp == NULL)
 878		return NULL;
 879	nfs4_init_seqid_counter(&lsp->ls_seqid);
 880	refcount_set(&lsp->ls_count, 1);
 881	lsp->ls_state = state;
 882	lsp->ls_owner = fl_owner;
 883	lsp->ls_seqid.owner_id = ida_alloc(&server->lockowner_id, GFP_KERNEL_ACCOUNT);
 884	if (lsp->ls_seqid.owner_id < 0)
 885		goto out_free;
 886	INIT_LIST_HEAD(&lsp->ls_locks);
 887	return lsp;
 888out_free:
 889	kfree(lsp);
 890	return NULL;
 891}
 892
 893void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
 894{
 895	ida_free(&server->lockowner_id, lsp->ls_seqid.owner_id);
 896	nfs4_destroy_seqid_counter(&lsp->ls_seqid);
 897	kfree(lsp);
 898}
 899
 900/*
 901 * Return a compatible lock_state. If no initialized lock_state structure
 902 * exists, return an uninitialized one.
 903 *
 904 */
 905static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 906{
 907	struct nfs4_lock_state *lsp, *new = NULL;
 908	
 909	for(;;) {
 910		spin_lock(&state->state_lock);
 911		lsp = __nfs4_find_lock_state(state, owner, NULL);
 912		if (lsp != NULL)
 913			break;
 914		if (new != NULL) {
 915			list_add(&new->ls_locks, &state->lock_states);
 916			set_bit(LK_STATE_IN_USE, &state->flags);
 917			lsp = new;
 918			new = NULL;
 919			break;
 920		}
 921		spin_unlock(&state->state_lock);
 922		new = nfs4_alloc_lock_state(state, owner);
 923		if (new == NULL)
 924			return NULL;
 925	}
 926	spin_unlock(&state->state_lock);
 927	if (new != NULL)
 928		nfs4_free_lock_state(state->owner->so_server, new);
 929	return lsp;
 930}
 931
 932/*
 933 * Release reference to lock_state, and free it if we see that
 934 * it is no longer in use
 935 */
 936void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 937{
 938	struct nfs_server *server;
 939	struct nfs4_state *state;
 940
 941	if (lsp == NULL)
 942		return;
 943	state = lsp->ls_state;
 944	if (!refcount_dec_and_lock(&lsp->ls_count, &state->state_lock))
 945		return;
 946	list_del(&lsp->ls_locks);
 947	if (list_empty(&state->lock_states))
 948		clear_bit(LK_STATE_IN_USE, &state->flags);
 949	spin_unlock(&state->state_lock);
 950	server = state->owner->so_server;
 951	if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
 952		struct nfs_client *clp = server->nfs_client;
 953
 954		clp->cl_mvops->free_lock_state(server, lsp);
 955	} else
 956		nfs4_free_lock_state(server, lsp);
 957}
 958
 959static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 960{
 961	struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 962
 963	dst->fl_u.nfs4_fl.owner = lsp;
 964	refcount_inc(&lsp->ls_count);
 965}
 966
 967static void nfs4_fl_release_lock(struct file_lock *fl)
 968{
 969	nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 970}
 971
 972static const struct file_lock_operations nfs4_fl_lock_ops = {
 973	.fl_copy_lock = nfs4_fl_copy_lock,
 974	.fl_release_private = nfs4_fl_release_lock,
 975};
 976
 977int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 978{
 979	struct nfs4_lock_state *lsp;
 980
 981	if (fl->fl_ops != NULL)
 982		return 0;
 983	lsp = nfs4_get_lock_state(state, fl->fl_owner);
 984	if (lsp == NULL)
 985		return -ENOMEM;
 986	fl->fl_u.nfs4_fl.owner = lsp;
 987	fl->fl_ops = &nfs4_fl_lock_ops;
 988	return 0;
 989}
 990
 991static int nfs4_copy_lock_stateid(nfs4_stateid *dst,
 992		struct nfs4_state *state,
 993		const struct nfs_lock_context *l_ctx)
 994{
 995	struct nfs4_lock_state *lsp;
 996	fl_owner_t fl_owner, fl_flock_owner;
 997	int ret = -ENOENT;
 998
 999	if (l_ctx == NULL)
1000		goto out;
1001
1002	if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
1003		goto out;
1004
1005	fl_owner = l_ctx->lockowner;
1006	fl_flock_owner = l_ctx->open_context->flock_owner;
1007
1008	spin_lock(&state->state_lock);
1009	lsp = __nfs4_find_lock_state(state, fl_owner, fl_flock_owner);
1010	if (lsp && test_bit(NFS_LOCK_LOST, &lsp->ls_flags))
1011		ret = -EIO;
1012	else if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
1013		nfs4_stateid_copy(dst, &lsp->ls_stateid);
1014		ret = 0;
1015	}
1016	spin_unlock(&state->state_lock);
1017	nfs4_put_lock_state(lsp);
1018out:
1019	return ret;
1020}
1021
1022bool nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
1023{
1024	bool ret;
1025	const nfs4_stateid *src;
1026	int seq;
1027
1028	do {
1029		ret = false;
1030		src = &zero_stateid;
1031		seq = read_seqbegin(&state->seqlock);
1032		if (test_bit(NFS_OPEN_STATE, &state->flags)) {
1033			src = &state->open_stateid;
1034			ret = true;
1035		}
1036		nfs4_stateid_copy(dst, src);
1037	} while (read_seqretry(&state->seqlock, seq));
1038	return ret;
1039}
1040
1041/*
1042 * Byte-range lock aware utility to initialize the stateid of read/write
1043 * requests.
1044 */
1045int nfs4_select_rw_stateid(struct nfs4_state *state,
1046		fmode_t fmode, const struct nfs_lock_context *l_ctx,
1047		nfs4_stateid *dst, const struct cred **cred)
1048{
1049	int ret;
1050
1051	if (!nfs4_valid_open_stateid(state))
1052		return -EIO;
1053	if (cred != NULL)
1054		*cred = NULL;
1055	ret = nfs4_copy_lock_stateid(dst, state, l_ctx);
1056	if (ret == -EIO)
1057		/* A lost lock - don't even consider delegations */
1058		goto out;
1059	/* returns true if delegation stateid found and copied */
1060	if (nfs4_copy_delegation_stateid(state->inode, fmode, dst, cred)) {
1061		ret = 0;
1062		goto out;
1063	}
1064	if (ret != -ENOENT)
1065		/* nfs4_copy_delegation_stateid() didn't over-write
1066		 * dst, so it still has the lock stateid which we now
1067		 * choose to use.
1068		 */
1069		goto out;
1070	ret = nfs4_copy_open_stateid(dst, state) ? 0 : -EAGAIN;
1071out:
1072	if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41))
1073		dst->seqid = 0;
1074	return ret;
1075}
1076
1077struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
1078{
1079	struct nfs_seqid *new;
1080
1081	new = kmalloc(sizeof(*new), gfp_mask);
1082	if (new == NULL)
1083		return ERR_PTR(-ENOMEM);
1084	new->sequence = counter;
1085	INIT_LIST_HEAD(&new->list);
1086	new->task = NULL;
1087	return new;
1088}
1089
1090void nfs_release_seqid(struct nfs_seqid *seqid)
1091{
1092	struct nfs_seqid_counter *sequence;
1093
1094	if (seqid == NULL || list_empty(&seqid->list))
1095		return;
1096	sequence = seqid->sequence;
1097	spin_lock(&sequence->lock);
1098	list_del_init(&seqid->list);
1099	if (!list_empty(&sequence->list)) {
1100		struct nfs_seqid *next;
1101
1102		next = list_first_entry(&sequence->list,
1103				struct nfs_seqid, list);
1104		rpc_wake_up_queued_task(&sequence->wait, next->task);
1105	}
1106	spin_unlock(&sequence->lock);
1107}
1108
1109void nfs_free_seqid(struct nfs_seqid *seqid)
1110{
1111	nfs_release_seqid(seqid);
1112	kfree(seqid);
1113}
1114
1115/*
1116 * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
1117 * failed with a seqid incrementing error -
1118 * see comments nfs4.h:seqid_mutating_error()
1119 */
1120static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
1121{
1122	switch (status) {
1123		case 0:
1124			break;
1125		case -NFS4ERR_BAD_SEQID:
1126			if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1127				return;
1128			pr_warn_ratelimited("NFS: v4 server returned a bad"
1129					" sequence-id error on an"
1130					" unconfirmed sequence %p!\n",
1131					seqid->sequence);
1132			return;
1133		case -NFS4ERR_STALE_CLIENTID:
1134		case -NFS4ERR_STALE_STATEID:
1135		case -NFS4ERR_BAD_STATEID:
1136		case -NFS4ERR_BADXDR:
1137		case -NFS4ERR_RESOURCE:
1138		case -NFS4ERR_NOFILEHANDLE:
1139		case -NFS4ERR_MOVED:
1140			/* Non-seqid mutating errors */
1141			return;
1142	}
1143	/*
1144	 * Note: no locking needed as we are guaranteed to be first
1145	 * on the sequence list
1146	 */
1147	seqid->sequence->counter++;
1148}
1149
1150void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1151{
1152	struct nfs4_state_owner *sp;
1153
1154	if (seqid == NULL)
1155		return;
1156
1157	sp = container_of(seqid->sequence, struct nfs4_state_owner, so_seqid);
1158	if (status == -NFS4ERR_BAD_SEQID)
1159		nfs4_reset_state_owner(sp);
1160	if (!nfs4_has_session(sp->so_server->nfs_client))
1161		nfs_increment_seqid(status, seqid);
1162}
1163
1164/*
1165 * Increment the seqid if the LOCK/LOCKU succeeded, or
1166 * failed with a seqid incrementing error -
1167 * see comments nfs4.h:seqid_mutating_error()
1168 */
1169void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1170{
1171	if (seqid != NULL)
1172		nfs_increment_seqid(status, seqid);
1173}
1174
1175int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1176{
1177	struct nfs_seqid_counter *sequence;
1178	int status = 0;
1179
1180	if (seqid == NULL)
1181		goto out;
1182	sequence = seqid->sequence;
1183	spin_lock(&sequence->lock);
1184	seqid->task = task;
1185	if (list_empty(&seqid->list))
1186		list_add_tail(&seqid->list, &sequence->list);
1187	if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1188		goto unlock;
1189	rpc_sleep_on(&sequence->wait, task, NULL);
1190	status = -EAGAIN;
1191unlock:
1192	spin_unlock(&sequence->lock);
1193out:
1194	return status;
1195}
1196
1197static int nfs4_run_state_manager(void *);
1198
1199static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1200{
1201	clear_and_wake_up_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
 
 
 
1202	rpc_wake_up(&clp->cl_rpcwaitq);
1203}
1204
1205/*
1206 * Schedule the nfs_client asynchronous state management routine
1207 */
1208void nfs4_schedule_state_manager(struct nfs_client *clp)
1209{
1210	struct task_struct *task;
1211	char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1212	struct rpc_clnt *clnt = clp->cl_rpcclient;
1213	bool swapon = false;
1214
1215	if (clnt->cl_shutdown)
1216		return;
1217
1218	set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
1219
1220	if (atomic_read(&clnt->cl_swapper)) {
1221		swapon = !test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE,
1222					   &clp->cl_state);
1223		if (!swapon) {
1224			wake_up_var(&clp->cl_state);
1225			return;
1226		}
1227	}
1228
1229	if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1230		return;
1231
1232	__module_get(THIS_MODULE);
1233	refcount_inc(&clp->cl_count);
1234
1235	/* The rcu_read_lock() is not strictly necessary, as the state
1236	 * manager is the only thread that ever changes the rpc_xprt
1237	 * after it's initialized.  At this point, we're single threaded. */
1238	rcu_read_lock();
1239	snprintf(buf, sizeof(buf), "%s-manager",
1240			rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1241	rcu_read_unlock();
1242	task = kthread_run(nfs4_run_state_manager, clp, "%s", buf);
1243	if (IS_ERR(task)) {
1244		printk(KERN_ERR "%s: kthread_run: %ld\n",
1245			__func__, PTR_ERR(task));
1246		if (!nfs_client_init_is_complete(clp))
1247			nfs_mark_client_ready(clp, PTR_ERR(task));
1248		if (swapon)
1249			clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state);
1250		nfs4_clear_state_manager_bit(clp);
1251		nfs_put_client(clp);
1252		module_put(THIS_MODULE);
1253	}
1254}
1255
1256/*
1257 * Schedule a lease recovery attempt
1258 */
1259void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1260{
1261	if (!clp)
1262		return;
1263	if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1264		set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1265	dprintk("%s: scheduling lease recovery for server %s\n", __func__,
1266			clp->cl_hostname);
1267	nfs4_schedule_state_manager(clp);
1268}
1269EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1270
1271/**
1272 * nfs4_schedule_migration_recovery - trigger migration recovery
1273 *
1274 * @server: FSID that is migrating
1275 *
1276 * Returns zero if recovery has started, otherwise a negative NFS4ERR
1277 * value is returned.
1278 */
1279int nfs4_schedule_migration_recovery(const struct nfs_server *server)
1280{
1281	struct nfs_client *clp = server->nfs_client;
1282
1283	if (server->fh_expire_type != NFS4_FH_PERSISTENT) {
1284		pr_err("NFS: volatile file handles not supported (server %s)\n",
1285				clp->cl_hostname);
1286		return -NFS4ERR_IO;
1287	}
1288
1289	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
1290		return -NFS4ERR_IO;
1291
1292	dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n",
1293			__func__,
1294			(unsigned long long)server->fsid.major,
1295			(unsigned long long)server->fsid.minor,
1296			clp->cl_hostname);
1297
1298	set_bit(NFS_MIG_IN_TRANSITION,
1299			&((struct nfs_server *)server)->mig_status);
1300	set_bit(NFS4CLNT_MOVED, &clp->cl_state);
1301
1302	nfs4_schedule_state_manager(clp);
1303	return 0;
1304}
1305EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
1306
1307/**
1308 * nfs4_schedule_lease_moved_recovery - start lease-moved recovery
1309 *
1310 * @clp: server to check for moved leases
1311 *
1312 */
1313void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp)
1314{
1315	dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n",
1316		__func__, clp->cl_clientid, clp->cl_hostname);
1317
1318	set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state);
1319	nfs4_schedule_state_manager(clp);
1320}
1321EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery);
1322
1323int nfs4_wait_clnt_recover(struct nfs_client *clp)
1324{
1325	int res;
1326
1327	might_sleep();
1328
1329	refcount_inc(&clp->cl_count);
1330	res = wait_on_bit_action(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
1331				 nfs_wait_bit_killable,
1332				 TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
1333	if (res)
1334		goto out;
1335	if (clp->cl_cons_state < 0)
1336		res = clp->cl_cons_state;
1337out:
1338	nfs_put_client(clp);
1339	return res;
1340}
1341
1342int nfs4_client_recover_expired_lease(struct nfs_client *clp)
1343{
1344	unsigned int loop;
1345	int ret;
1346
1347	for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) {
1348		ret = nfs4_wait_clnt_recover(clp);
1349		if (ret != 0)
1350			break;
1351		if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) &&
1352		    !test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state))
1353			break;
1354		nfs4_schedule_state_manager(clp);
1355		ret = -EIO;
1356	}
1357	return ret;
1358}
1359
1360/*
1361 * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1362 * @clp: client to process
1363 *
1364 * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1365 * resend of the SETCLIENTID and hence re-establish the
1366 * callback channel. Then return all existing delegations.
1367 */
1368static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1369{
1370	set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1371	nfs_expire_all_delegations(clp);
1372	dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__,
1373			clp->cl_hostname);
1374}
1375
1376void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1377{
1378	nfs40_handle_cb_pathdown(clp);
1379	nfs4_schedule_state_manager(clp);
1380}
1381
1382static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1383{
1384
1385	if (!nfs4_valid_open_stateid(state))
1386		return 0;
1387	set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1388	/* Don't recover state that expired before the reboot */
1389	if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1390		clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1391		return 0;
1392	}
1393	set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1394	set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1395	return 1;
1396}
1397
1398int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1399{
1400	if (!nfs4_valid_open_stateid(state))
1401		return 0;
1402	set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1403	clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1404	set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1405	set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1406	return 1;
1407}
1408
1409int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1410{
1411	struct nfs_client *clp = server->nfs_client;
1412
1413	if (!nfs4_state_mark_reclaim_nograce(clp, state))
1414		return -EBADF;
1415	nfs_inode_find_delegation_state_and_recover(state->inode,
1416			&state->stateid);
1417	dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
1418			clp->cl_hostname);
1419	nfs4_schedule_state_manager(clp);
1420	return 0;
1421}
1422EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1423
1424static struct nfs4_lock_state *
1425nfs_state_find_lock_state_by_stateid(struct nfs4_state *state,
1426		const nfs4_stateid *stateid)
1427{
1428	struct nfs4_lock_state *pos;
1429
1430	list_for_each_entry(pos, &state->lock_states, ls_locks) {
1431		if (!test_bit(NFS_LOCK_INITIALIZED, &pos->ls_flags))
1432			continue;
1433		if (nfs4_stateid_match_or_older(&pos->ls_stateid, stateid))
1434			return pos;
1435	}
1436	return NULL;
1437}
1438
1439static bool nfs_state_lock_state_matches_stateid(struct nfs4_state *state,
1440		const nfs4_stateid *stateid)
1441{
1442	bool found = false;
1443
1444	if (test_bit(LK_STATE_IN_USE, &state->flags)) {
1445		spin_lock(&state->state_lock);
1446		if (nfs_state_find_lock_state_by_stateid(state, stateid))
1447			found = true;
1448		spin_unlock(&state->state_lock);
1449	}
1450	return found;
1451}
1452
1453void nfs_inode_find_state_and_recover(struct inode *inode,
1454		const nfs4_stateid *stateid)
1455{
1456	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1457	struct nfs_inode *nfsi = NFS_I(inode);
1458	struct nfs_open_context *ctx;
1459	struct nfs4_state *state;
1460	bool found = false;
1461
1462	rcu_read_lock();
1463	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1464		state = ctx->state;
1465		if (state == NULL)
1466			continue;
1467		if (nfs4_stateid_match_or_older(&state->stateid, stateid) &&
1468		    nfs4_state_mark_reclaim_nograce(clp, state)) {
1469			found = true;
1470			continue;
1471		}
1472		if (test_bit(NFS_OPEN_STATE, &state->flags) &&
1473		    nfs4_stateid_match_or_older(&state->open_stateid, stateid) &&
1474		    nfs4_state_mark_reclaim_nograce(clp, state)) {
1475			found = true;
1476			continue;
1477		}
1478		if (nfs_state_lock_state_matches_stateid(state, stateid) &&
1479		    nfs4_state_mark_reclaim_nograce(clp, state))
1480			found = true;
1481	}
1482	rcu_read_unlock();
1483
1484	nfs_inode_find_delegation_state_and_recover(inode, stateid);
1485	if (found)
1486		nfs4_schedule_state_manager(clp);
1487}
1488
1489static void nfs4_state_mark_open_context_bad(struct nfs4_state *state, int err)
1490{
1491	struct inode *inode = state->inode;
1492	struct nfs_inode *nfsi = NFS_I(inode);
1493	struct nfs_open_context *ctx;
1494
1495	rcu_read_lock();
1496	list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
1497		if (ctx->state != state)
1498			continue;
1499		set_bit(NFS_CONTEXT_BAD, &ctx->flags);
1500		pr_warn("NFSv4: state recovery failed for open file %pd2, "
1501				"error = %d\n", ctx->dentry, err);
1502	}
1503	rcu_read_unlock();
1504}
1505
1506static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)
1507{
1508	set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags);
1509	nfs4_state_mark_open_context_bad(state, error);
1510}
1511
1512
1513static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1514{
1515	struct inode *inode = state->inode;
1516	struct nfs_inode *nfsi = NFS_I(inode);
1517	struct file_lock *fl;
1518	struct nfs4_lock_state *lsp;
1519	int status = 0;
1520	struct file_lock_context *flctx = locks_inode_context(inode);
1521	struct list_head *list;
1522
1523	if (flctx == NULL)
1524		return 0;
1525
1526	list = &flctx->flc_posix;
1527
1528	/* Guard against delegation returns and new lock/unlock calls */
1529	down_write(&nfsi->rwsem);
1530	spin_lock(&flctx->flc_lock);
1531restart:
1532	list_for_each_entry(fl, list, fl_list) {
1533		if (nfs_file_open_context(fl->fl_file)->state != state)
1534			continue;
1535		spin_unlock(&flctx->flc_lock);
1536		status = ops->recover_lock(state, fl);
1537		switch (status) {
1538		case 0:
1539			break;
1540		case -ETIMEDOUT:
1541		case -ESTALE:
1542		case -NFS4ERR_ADMIN_REVOKED:
1543		case -NFS4ERR_STALE_STATEID:
1544		case -NFS4ERR_BAD_STATEID:
1545		case -NFS4ERR_EXPIRED:
1546		case -NFS4ERR_NO_GRACE:
1547		case -NFS4ERR_STALE_CLIENTID:
1548		case -NFS4ERR_BADSESSION:
1549		case -NFS4ERR_BADSLOT:
1550		case -NFS4ERR_BAD_HIGH_SLOT:
1551		case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1552			goto out;
1553		default:
1554			pr_err("NFS: %s: unhandled error %d\n",
1555					__func__, status);
1556			fallthrough;
1557		case -ENOMEM:
1558		case -NFS4ERR_DENIED:
1559		case -NFS4ERR_RECLAIM_BAD:
1560		case -NFS4ERR_RECLAIM_CONFLICT:
1561			lsp = fl->fl_u.nfs4_fl.owner;
1562			if (lsp)
1563				set_bit(NFS_LOCK_LOST, &lsp->ls_flags);
1564			status = 0;
1565		}
1566		spin_lock(&flctx->flc_lock);
1567	}
1568	if (list == &flctx->flc_posix) {
1569		list = &flctx->flc_flock;
1570		goto restart;
1571	}
1572	spin_unlock(&flctx->flc_lock);
1573out:
1574	up_write(&nfsi->rwsem);
1575	return status;
1576}
1577
1578#ifdef CONFIG_NFS_V4_2
1579static void nfs42_complete_copies(struct nfs4_state_owner *sp, struct nfs4_state *state)
1580{
1581	struct nfs4_copy_state *copy;
1582
1583	if (!test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags) &&
1584		!test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags))
1585		return;
1586
1587	spin_lock(&sp->so_server->nfs_client->cl_lock);
1588	list_for_each_entry(copy, &sp->so_server->ss_copies, copies) {
1589		if ((test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags) &&
1590				!nfs4_stateid_match_other(&state->stateid,
1591				&copy->parent_dst_state->stateid)))
1592				continue;
1593		copy->flags = 1;
1594		if (test_and_clear_bit(NFS_CLNT_DST_SSC_COPY_STATE,
1595				&state->flags)) {
1596			clear_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags);
1597			complete(&copy->completion);
1598		}
1599	}
1600	list_for_each_entry(copy, &sp->so_server->ss_copies, src_copies) {
1601		if ((test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags) &&
1602				!nfs4_stateid_match_other(&state->stateid,
1603				&copy->parent_src_state->stateid)))
1604				continue;
1605		copy->flags = 1;
1606		if (test_and_clear_bit(NFS_CLNT_DST_SSC_COPY_STATE,
1607				&state->flags))
1608			complete(&copy->completion);
1609	}
1610	spin_unlock(&sp->so_server->nfs_client->cl_lock);
1611}
1612#else /* !CONFIG_NFS_V4_2 */
1613static inline void nfs42_complete_copies(struct nfs4_state_owner *sp,
1614					 struct nfs4_state *state)
1615{
1616}
1617#endif /* CONFIG_NFS_V4_2 */
1618
1619static int __nfs4_reclaim_open_state(struct nfs4_state_owner *sp, struct nfs4_state *state,
1620				     const struct nfs4_state_recovery_ops *ops,
1621				     int *lost_locks)
1622{
1623	struct nfs4_lock_state *lock;
1624	int status;
1625
1626	status = ops->recover_open(sp, state);
1627	if (status < 0)
1628		return status;
1629
1630	status = nfs4_reclaim_locks(state, ops);
1631	if (status < 0)
1632		return status;
1633
1634	if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) {
1635		spin_lock(&state->state_lock);
1636		list_for_each_entry(lock, &state->lock_states, ls_locks) {
1637			trace_nfs4_state_lock_reclaim(state, lock);
1638			if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags) &&
1639			    !test_bit(NFS_LOCK_UNLOCKING, &lock->ls_flags))
1640				*lost_locks += 1;
1641		}
1642		spin_unlock(&state->state_lock);
1643	}
1644
1645	nfs42_complete_copies(sp, state);
1646	clear_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1647	return status;
1648}
1649
1650static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp,
1651				   const struct nfs4_state_recovery_ops *ops,
1652				   int *lost_locks)
1653{
1654	struct nfs4_state *state;
1655	unsigned int loop = 0;
1656	int status = 0;
1657#ifdef CONFIG_NFS_V4_2
1658	bool found_ssc_copy_state = false;
1659#endif /* CONFIG_NFS_V4_2 */
1660
1661	/* Note: we rely on the sp->so_states list being ordered 
1662	 * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1663	 * states first.
1664	 * This is needed to ensure that the server won't give us any
1665	 * read delegations that we have to return if, say, we are
1666	 * recovering after a network partition or a reboot from a
1667	 * server that doesn't support a grace period.
1668	 */
1669	spin_lock(&sp->so_lock);
1670	raw_write_seqcount_begin(&sp->so_reclaim_seqcount);
1671restart:
1672	list_for_each_entry(state, &sp->so_states, open_states) {
1673		if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1674			continue;
1675		if (!nfs4_valid_open_stateid(state))
1676			continue;
1677		if (state->state == 0)
1678			continue;
1679#ifdef CONFIG_NFS_V4_2
1680		if (test_bit(NFS_SRV_SSC_COPY_STATE, &state->flags)) {
1681			nfs4_state_mark_recovery_failed(state, -EIO);
1682			found_ssc_copy_state = true;
1683			continue;
1684		}
1685#endif /* CONFIG_NFS_V4_2 */
1686		refcount_inc(&state->count);
1687		spin_unlock(&sp->so_lock);
1688		status = __nfs4_reclaim_open_state(sp, state, ops, lost_locks);
1689
1690		switch (status) {
1691		default:
1692			if (status >= 0) {
1693				loop = 0;
1694				break;
1695			}
1696			printk(KERN_ERR "NFS: %s: unhandled error %d\n", __func__, status);
1697			fallthrough;
1698		case -ENOENT:
1699		case -ENOMEM:
1700		case -EACCES:
1701		case -EROFS:
1702		case -EIO:
1703		case -ESTALE:
1704			/* Open state on this file cannot be recovered */
1705			nfs4_state_mark_recovery_failed(state, status);
1706			break;
1707		case -EAGAIN:
1708			ssleep(1);
1709			if (loop++ < 10) {
1710				set_bit(ops->state_flag_bit, &state->flags);
1711				break;
1712			}
1713			fallthrough;
1714		case -NFS4ERR_ADMIN_REVOKED:
1715		case -NFS4ERR_STALE_STATEID:
1716		case -NFS4ERR_OLD_STATEID:
1717		case -NFS4ERR_BAD_STATEID:
1718		case -NFS4ERR_RECLAIM_BAD:
1719		case -NFS4ERR_RECLAIM_CONFLICT:
1720			nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1721			break;
1722		case -NFS4ERR_EXPIRED:
1723		case -NFS4ERR_NO_GRACE:
1724			nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1725			fallthrough;
1726		case -NFS4ERR_STALE_CLIENTID:
1727		case -NFS4ERR_BADSESSION:
1728		case -NFS4ERR_BADSLOT:
1729		case -NFS4ERR_BAD_HIGH_SLOT:
1730		case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1731		case -ETIMEDOUT:
1732			goto out_err;
1733		}
1734		nfs4_put_open_state(state);
1735		spin_lock(&sp->so_lock);
1736		goto restart;
1737	}
1738	raw_write_seqcount_end(&sp->so_reclaim_seqcount);
1739	spin_unlock(&sp->so_lock);
1740#ifdef CONFIG_NFS_V4_2
1741	if (found_ssc_copy_state)
1742		return -EIO;
1743#endif /* CONFIG_NFS_V4_2 */
1744	return 0;
1745out_err:
1746	nfs4_put_open_state(state);
1747	spin_lock(&sp->so_lock);
1748	raw_write_seqcount_end(&sp->so_reclaim_seqcount);
1749	spin_unlock(&sp->so_lock);
1750	return status;
1751}
1752
1753static void nfs4_clear_open_state(struct nfs4_state *state)
1754{
1755	struct nfs4_lock_state *lock;
1756
1757	clear_bit(NFS_DELEGATED_STATE, &state->flags);
1758	clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1759	clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1760	clear_bit(NFS_O_RDWR_STATE, &state->flags);
1761	spin_lock(&state->state_lock);
1762	list_for_each_entry(lock, &state->lock_states, ls_locks) {
1763		lock->ls_seqid.flags = 0;
1764		clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags);
1765	}
1766	spin_unlock(&state->state_lock);
1767}
1768
1769static void nfs4_reset_seqids(struct nfs_server *server,
1770	int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1771{
1772	struct nfs_client *clp = server->nfs_client;
1773	struct nfs4_state_owner *sp;
1774	struct rb_node *pos;
1775	struct nfs4_state *state;
1776
1777	spin_lock(&clp->cl_lock);
1778	for (pos = rb_first(&server->state_owners);
1779	     pos != NULL;
1780	     pos = rb_next(pos)) {
1781		sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1782		sp->so_seqid.flags = 0;
1783		spin_lock(&sp->so_lock);
1784		list_for_each_entry(state, &sp->so_states, open_states) {
1785			if (mark_reclaim(clp, state))
1786				nfs4_clear_open_state(state);
1787		}
1788		spin_unlock(&sp->so_lock);
1789	}
1790	spin_unlock(&clp->cl_lock);
1791}
1792
1793static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1794	int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1795{
1796	struct nfs_server *server;
1797
1798	rcu_read_lock();
1799	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1800		nfs4_reset_seqids(server, mark_reclaim);
1801	rcu_read_unlock();
1802}
1803
1804static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1805{
1806	set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1807	/* Mark all delegations for reclaim */
1808	nfs_delegation_mark_reclaim(clp);
1809	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1810}
1811
1812static int nfs4_reclaim_complete(struct nfs_client *clp,
1813				 const struct nfs4_state_recovery_ops *ops,
1814				 const struct cred *cred)
1815{
1816	/* Notify the server we're done reclaiming our state */
1817	if (ops->reclaim_complete)
1818		return ops->reclaim_complete(clp, cred);
1819	return 0;
1820}
1821
1822static void nfs4_clear_reclaim_server(struct nfs_server *server)
1823{
1824	struct nfs_client *clp = server->nfs_client;
1825	struct nfs4_state_owner *sp;
1826	struct rb_node *pos;
1827	struct nfs4_state *state;
1828
1829	spin_lock(&clp->cl_lock);
1830	for (pos = rb_first(&server->state_owners);
1831	     pos != NULL;
1832	     pos = rb_next(pos)) {
1833		sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1834		spin_lock(&sp->so_lock);
1835		list_for_each_entry(state, &sp->so_states, open_states) {
1836			if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1837						&state->flags))
1838				continue;
1839			nfs4_state_mark_reclaim_nograce(clp, state);
1840		}
1841		spin_unlock(&sp->so_lock);
1842	}
1843	spin_unlock(&clp->cl_lock);
1844}
1845
1846static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1847{
1848	struct nfs_server *server;
1849
1850	if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1851		return 0;
1852
1853	rcu_read_lock();
1854	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1855		nfs4_clear_reclaim_server(server);
1856	rcu_read_unlock();
1857
1858	nfs_delegation_reap_unclaimed(clp);
1859	return 1;
1860}
1861
1862static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1863{
1864	const struct nfs4_state_recovery_ops *ops;
1865	const struct cred *cred;
1866	int err;
1867
1868	if (!nfs4_state_clear_reclaim_reboot(clp))
1869		return;
1870	ops = clp->cl_mvops->reboot_recovery_ops;
1871	cred = nfs4_get_clid_cred(clp);
1872	err = nfs4_reclaim_complete(clp, ops, cred);
1873	put_cred(cred);
1874	if (err == -NFS4ERR_CONN_NOT_BOUND_TO_SESSION)
1875		set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1876}
1877
1878static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1879{
1880	nfs_mark_test_expired_all_delegations(clp);
1881	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1882}
1883
1884static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1885{
1886	switch (error) {
1887	case 0:
1888		break;
1889	case -NFS4ERR_CB_PATH_DOWN:
1890		nfs40_handle_cb_pathdown(clp);
1891		break;
1892	case -NFS4ERR_NO_GRACE:
1893		nfs4_state_end_reclaim_reboot(clp);
1894		break;
1895	case -NFS4ERR_STALE_CLIENTID:
1896		set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1897		nfs4_state_start_reclaim_reboot(clp);
1898		break;
1899	case -NFS4ERR_EXPIRED:
1900		set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1901		nfs4_state_start_reclaim_nograce(clp);
1902		break;
1903	case -NFS4ERR_BADSESSION:
1904	case -NFS4ERR_BADSLOT:
1905	case -NFS4ERR_BAD_HIGH_SLOT:
1906	case -NFS4ERR_DEADSESSION:
1907	case -NFS4ERR_SEQ_FALSE_RETRY:
1908	case -NFS4ERR_SEQ_MISORDERED:
1909		set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1910		/* Zero session reset errors */
1911		break;
1912	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1913		set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1914		break;
1915	default:
1916		dprintk("%s: failed to handle error %d for server %s\n",
1917				__func__, error, clp->cl_hostname);
1918		return error;
1919	}
1920	dprintk("%s: handled error %d for server %s\n", __func__, error,
1921			clp->cl_hostname);
1922	return 0;
1923}
1924
1925static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1926{
1927	struct nfs4_state_owner *sp;
1928	struct nfs_server *server;
1929	struct rb_node *pos;
1930	LIST_HEAD(freeme);
1931	int status = 0;
1932	int lost_locks = 0;
1933
1934restart:
1935	rcu_read_lock();
1936	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1937		nfs4_purge_state_owners(server, &freeme);
1938		spin_lock(&clp->cl_lock);
1939		for (pos = rb_first(&server->state_owners);
1940		     pos != NULL;
1941		     pos = rb_next(pos)) {
1942			sp = rb_entry(pos,
1943				struct nfs4_state_owner, so_server_node);
1944			if (!test_and_clear_bit(ops->owner_flag_bit,
1945							&sp->so_flags))
1946				continue;
1947			if (!atomic_inc_not_zero(&sp->so_count))
1948				continue;
1949			spin_unlock(&clp->cl_lock);
1950			rcu_read_unlock();
1951
1952			status = nfs4_reclaim_open_state(sp, ops, &lost_locks);
1953			if (status < 0) {
1954				if (lost_locks)
1955					pr_warn("NFS: %s: lost %d locks\n",
1956						clp->cl_hostname, lost_locks);
1957				set_bit(ops->owner_flag_bit, &sp->so_flags);
1958				nfs4_put_state_owner(sp);
1959				status = nfs4_recovery_handle_error(clp, status);
1960				return (status != 0) ? status : -EAGAIN;
1961			}
1962
1963			nfs4_put_state_owner(sp);
1964			goto restart;
1965		}
1966		spin_unlock(&clp->cl_lock);
1967	}
1968	rcu_read_unlock();
1969	nfs4_free_state_owners(&freeme);
1970	if (lost_locks)
1971		pr_warn("NFS: %s: lost %d locks\n",
1972			clp->cl_hostname, lost_locks);
1973	return 0;
1974}
1975
1976static int nfs4_check_lease(struct nfs_client *clp)
1977{
1978	const struct cred *cred;
1979	const struct nfs4_state_maintenance_ops *ops =
1980		clp->cl_mvops->state_renewal_ops;
1981	int status;
1982
1983	/* Is the client already known to have an expired lease? */
1984	if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1985		return 0;
1986	cred = ops->get_state_renewal_cred(clp);
1987	if (cred == NULL) {
1988		cred = nfs4_get_clid_cred(clp);
1989		status = -ENOKEY;
1990		if (cred == NULL)
1991			goto out;
1992	}
1993	status = ops->renew_lease(clp, cred);
1994	put_cred(cred);
1995	if (status == -ETIMEDOUT) {
1996		set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1997		return 0;
1998	}
1999out:
2000	return nfs4_recovery_handle_error(clp, status);
2001}
2002
2003/* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors
2004 * and for recoverable errors on EXCHANGE_ID for v4.1
2005 */
2006static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
2007{
2008	switch (status) {
2009	case -NFS4ERR_SEQ_MISORDERED:
2010		if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
2011			return -ESERVERFAULT;
2012		/* Lease confirmation error: retry after purging the lease */
2013		ssleep(1);
2014		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
2015		break;
2016	case -NFS4ERR_STALE_CLIENTID:
2017		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
2018		nfs4_state_start_reclaim_reboot(clp);
2019		break;
2020	case -NFS4ERR_CLID_INUSE:
2021		pr_err("NFS: Server %s reports our clientid is in use\n",
2022			clp->cl_hostname);
2023		nfs_mark_client_ready(clp, -EPERM);
2024		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
2025		return -EPERM;
2026	case -EACCES:
2027	case -NFS4ERR_DELAY:
2028	case -EAGAIN:
2029		ssleep(1);
2030		break;
2031
2032	case -NFS4ERR_MINOR_VERS_MISMATCH:
2033		if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
2034			nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
2035		dprintk("%s: exit with error %d for server %s\n",
2036				__func__, -EPROTONOSUPPORT, clp->cl_hostname);
2037		return -EPROTONOSUPPORT;
2038	case -ENOSPC:
2039		if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
2040			nfs_mark_client_ready(clp, -EIO);
2041		return -EIO;
2042	case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
2043				 * in nfs4_exchange_id */
2044	default:
2045		dprintk("%s: exit with error %d for server %s\n", __func__,
2046				status, clp->cl_hostname);
2047		return status;
2048	}
2049	set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
2050	dprintk("%s: handled error %d for server %s\n", __func__, status,
2051			clp->cl_hostname);
2052	return 0;
2053}
2054
2055static int nfs4_establish_lease(struct nfs_client *clp)
2056{
2057	const struct cred *cred;
2058	const struct nfs4_state_recovery_ops *ops =
2059		clp->cl_mvops->reboot_recovery_ops;
2060	int status;
2061
2062	status = nfs4_begin_drain_session(clp);
2063	if (status != 0)
2064		return status;
2065	cred = nfs4_get_clid_cred(clp);
2066	if (cred == NULL)
2067		return -ENOENT;
2068	status = ops->establish_clid(clp, cred);
2069	put_cred(cred);
2070	if (status != 0)
2071		return status;
2072	pnfs_destroy_all_layouts(clp);
2073	return 0;
2074}
2075
2076/*
2077 * Returns zero or a negative errno.  NFS4ERR values are converted
2078 * to local errno values.
2079 */
2080static int nfs4_reclaim_lease(struct nfs_client *clp)
2081{
2082	int status;
2083
2084	status = nfs4_establish_lease(clp);
2085	if (status < 0)
2086		return nfs4_handle_reclaim_lease_error(clp, status);
2087	if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state))
2088		nfs4_state_start_reclaim_nograce(clp);
2089	if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
2090		set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
2091	clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
2092	clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
2093	return 0;
2094}
2095
2096static int nfs4_purge_lease(struct nfs_client *clp)
2097{
2098	int status;
2099
2100	status = nfs4_establish_lease(clp);
2101	if (status < 0)
2102		return nfs4_handle_reclaim_lease_error(clp, status);
2103	clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
2104	set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
2105	nfs4_state_start_reclaim_nograce(clp);
2106	return 0;
2107}
2108
2109/*
2110 * Try remote migration of one FSID from a source server to a
2111 * destination server.  The source server provides a list of
2112 * potential destinations.
2113 *
2114 * Returns zero or a negative NFS4ERR status code.
2115 */
2116static int nfs4_try_migration(struct nfs_server *server, const struct cred *cred)
2117{
2118	struct nfs_client *clp = server->nfs_client;
2119	struct nfs4_fs_locations *locations = NULL;
2120	struct inode *inode;
2121	struct page *page;
2122	int status, result;
2123
2124	dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__,
2125			(unsigned long long)server->fsid.major,
2126			(unsigned long long)server->fsid.minor,
2127			clp->cl_hostname);
2128
2129	result = 0;
2130	page = alloc_page(GFP_KERNEL);
2131	locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
2132	if (page == NULL || locations == NULL) {
2133		dprintk("<-- %s: no memory\n", __func__);
2134		goto out;
2135	}
2136	locations->fattr = nfs_alloc_fattr();
2137	if (locations->fattr == NULL) {
2138		dprintk("<-- %s: no memory\n", __func__);
2139		goto out;
2140	}
2141
2142	inode = d_inode(server->super->s_root);
2143	result = nfs4_proc_get_locations(server, NFS_FH(inode), locations,
2144					 page, cred);
2145	if (result) {
2146		dprintk("<-- %s: failed to retrieve fs_locations: %d\n",
2147			__func__, result);
2148		goto out;
2149	}
2150
2151	result = -NFS4ERR_NXIO;
2152	if (!locations->nlocations)
2153		goto out;
2154
2155	if (!(locations->fattr->valid & NFS_ATTR_FATTR_V4_LOCATIONS)) {
2156		dprintk("<-- %s: No fs_locations data, migration skipped\n",
2157			__func__);
2158		goto out;
2159	}
2160
2161	status = nfs4_begin_drain_session(clp);
2162	if (status != 0) {
2163		result = status;
2164		goto out;
2165	}
2166
2167	status = nfs4_replace_transport(server, locations);
2168	if (status != 0) {
2169		dprintk("<-- %s: failed to replace transport: %d\n",
2170			__func__, status);
2171		goto out;
2172	}
2173
2174	result = 0;
2175	dprintk("<-- %s: migration succeeded\n", __func__);
2176
2177out:
2178	if (page != NULL)
2179		__free_page(page);
2180	if (locations != NULL)
2181		kfree(locations->fattr);
2182	kfree(locations);
2183	if (result) {
2184		pr_err("NFS: migration recovery failed (server %s)\n",
2185				clp->cl_hostname);
2186		set_bit(NFS_MIG_FAILED, &server->mig_status);
2187	}
2188	return result;
2189}
2190
2191/*
2192 * Returns zero or a negative NFS4ERR status code.
2193 */
2194static int nfs4_handle_migration(struct nfs_client *clp)
2195{
2196	const struct nfs4_state_maintenance_ops *ops =
2197				clp->cl_mvops->state_renewal_ops;
2198	struct nfs_server *server;
2199	const struct cred *cred;
2200
2201	dprintk("%s: migration reported on \"%s\"\n", __func__,
2202			clp->cl_hostname);
2203
2204	cred = ops->get_state_renewal_cred(clp);
2205	if (cred == NULL)
2206		return -NFS4ERR_NOENT;
2207
2208	clp->cl_mig_gen++;
2209restart:
2210	rcu_read_lock();
2211	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
2212		int status;
2213
2214		if (server->mig_gen == clp->cl_mig_gen)
2215			continue;
2216		server->mig_gen = clp->cl_mig_gen;
2217
2218		if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION,
2219						&server->mig_status))
2220			continue;
2221
2222		rcu_read_unlock();
2223		status = nfs4_try_migration(server, cred);
2224		if (status < 0) {
2225			put_cred(cred);
2226			return status;
2227		}
2228		goto restart;
2229	}
2230	rcu_read_unlock();
2231	put_cred(cred);
2232	return 0;
2233}
2234
2235/*
2236 * Test each nfs_server on the clp's cl_superblocks list to see
2237 * if it's moved to another server.  Stop when the server no longer
2238 * returns NFS4ERR_LEASE_MOVED.
2239 */
2240static int nfs4_handle_lease_moved(struct nfs_client *clp)
2241{
2242	const struct nfs4_state_maintenance_ops *ops =
2243				clp->cl_mvops->state_renewal_ops;
2244	struct nfs_server *server;
2245	const struct cred *cred;
2246
2247	dprintk("%s: lease moved reported on \"%s\"\n", __func__,
2248			clp->cl_hostname);
2249
2250	cred = ops->get_state_renewal_cred(clp);
2251	if (cred == NULL)
2252		return -NFS4ERR_NOENT;
2253
2254	clp->cl_mig_gen++;
2255restart:
2256	rcu_read_lock();
2257	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
2258		struct inode *inode;
2259		int status;
2260
2261		if (server->mig_gen == clp->cl_mig_gen)
2262			continue;
2263		server->mig_gen = clp->cl_mig_gen;
2264
2265		rcu_read_unlock();
2266
2267		inode = d_inode(server->super->s_root);
2268		status = nfs4_proc_fsid_present(inode, cred);
2269		if (status != -NFS4ERR_MOVED)
2270			goto restart;	/* wasn't this one */
2271		if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED)
2272			goto restart;	/* there are more */
2273		goto out;
2274	}
2275	rcu_read_unlock();
2276
2277out:
2278	put_cred(cred);
2279	return 0;
2280}
2281
2282/**
2283 * nfs4_discover_server_trunking - Detect server IP address trunking
2284 *
2285 * @clp: nfs_client under test
2286 * @result: OUT: found nfs_client, or clp
2287 *
2288 * Returns zero or a negative errno.  If zero is returned,
2289 * an nfs_client pointer is planted in "result".
2290 *
2291 * Note: since we are invoked in process context, and
2292 * not from inside the state manager, we cannot use
2293 * nfs4_handle_reclaim_lease_error().
2294 */
2295int nfs4_discover_server_trunking(struct nfs_client *clp,
2296				  struct nfs_client **result)
2297{
2298	const struct nfs4_state_recovery_ops *ops =
2299				clp->cl_mvops->reboot_recovery_ops;
2300	struct rpc_clnt *clnt;
2301	const struct cred *cred;
2302	int i, status;
2303
2304	dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
2305
2306	clnt = clp->cl_rpcclient;
2307	i = 0;
2308
2309	mutex_lock(&nfs_clid_init_mutex);
2310again:
2311	status  = -ENOENT;
2312	cred = nfs4_get_clid_cred(clp);
2313	if (cred == NULL)
2314		goto out_unlock;
2315
2316	status = ops->detect_trunking(clp, result, cred);
2317	put_cred(cred);
2318	switch (status) {
2319	case 0:
2320	case -EINTR:
2321	case -ERESTARTSYS:
2322		break;
2323	case -ETIMEDOUT:
2324		if (clnt->cl_softrtry)
2325			break;
2326		fallthrough;
2327	case -NFS4ERR_DELAY:
2328	case -EAGAIN:
2329		ssleep(1);
2330		fallthrough;
2331	case -NFS4ERR_STALE_CLIENTID:
2332		dprintk("NFS: %s after status %d, retrying\n",
2333			__func__, status);
2334		goto again;
2335	case -EACCES:
2336		if (i++ == 0) {
2337			nfs4_root_machine_cred(clp);
2338			goto again;
2339		}
2340		if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX)
2341			break;
2342		fallthrough;
2343	case -NFS4ERR_CLID_INUSE:
2344	case -NFS4ERR_WRONGSEC:
2345		/* No point in retrying if we already used RPC_AUTH_UNIX */
2346		if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) {
2347			status = -EPERM;
2348			break;
2349		}
2350		clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
2351		if (IS_ERR(clnt)) {
2352			status = PTR_ERR(clnt);
2353			break;
2354		}
2355		/* Note: this is safe because we haven't yet marked the
2356		 * client as ready, so we are the only user of
2357		 * clp->cl_rpcclient
2358		 */
2359		clnt = xchg(&clp->cl_rpcclient, clnt);
2360		rpc_shutdown_client(clnt);
2361		clnt = clp->cl_rpcclient;
2362		goto again;
2363
2364	case -NFS4ERR_MINOR_VERS_MISMATCH:
2365		status = -EPROTONOSUPPORT;
2366		break;
2367
2368	case -EKEYEXPIRED:
2369	case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
2370				 * in nfs4_exchange_id */
2371		status = -EKEYEXPIRED;
2372		break;
2373	default:
2374		pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
2375				__func__, status);
2376		status = -EIO;
2377	}
2378
2379out_unlock:
2380	mutex_unlock(&nfs_clid_init_mutex);
2381	dprintk("NFS: %s: status = %d\n", __func__, status);
2382	return status;
2383}
2384
2385#ifdef CONFIG_NFS_V4_1
2386void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
2387{
2388	struct nfs_client *clp = session->clp;
2389
2390	switch (err) {
2391	default:
2392		set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2393		break;
2394	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
2395		set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2396	}
2397	nfs4_schedule_state_manager(clp);
2398}
2399EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
2400
2401void nfs41_notify_server(struct nfs_client *clp)
2402{
2403	/* Use CHECK_LEASE to ping the server with a SEQUENCE */
2404	set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
2405	nfs4_schedule_state_manager(clp);
2406}
2407
2408static void nfs4_reset_all_state(struct nfs_client *clp)
2409{
2410	if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
2411		set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
2412		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
2413		nfs4_state_start_reclaim_nograce(clp);
2414		dprintk("%s: scheduling reset of all state for server %s!\n",
2415				__func__, clp->cl_hostname);
2416		nfs4_schedule_state_manager(clp);
2417	}
2418}
2419
2420static void nfs41_handle_server_reboot(struct nfs_client *clp)
2421{
2422	if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
2423		nfs4_state_start_reclaim_reboot(clp);
2424		dprintk("%s: server %s rebooted!\n", __func__,
2425				clp->cl_hostname);
2426		nfs4_schedule_state_manager(clp);
2427	}
2428}
2429
2430static void nfs41_handle_all_state_revoked(struct nfs_client *clp)
2431{
2432	nfs4_reset_all_state(clp);
2433	dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
2434}
2435
2436static void nfs41_handle_some_state_revoked(struct nfs_client *clp)
2437{
2438	nfs4_state_start_reclaim_nograce(clp);
2439	nfs4_schedule_state_manager(clp);
2440
2441	dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
2442}
2443
2444static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
2445{
2446	/* FIXME: For now, we destroy all layouts. */
2447	pnfs_destroy_all_layouts(clp);
2448	nfs_test_expired_all_delegations(clp);
2449	dprintk("%s: Recallable state revoked on server %s!\n", __func__,
2450			clp->cl_hostname);
2451}
2452
2453static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
2454{
2455	set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2456	nfs4_schedule_state_manager(clp);
2457
2458	dprintk("%s: server %s declared a backchannel fault\n", __func__,
2459			clp->cl_hostname);
2460}
2461
2462static void nfs41_handle_cb_path_down(struct nfs_client *clp)
2463{
2464	if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2465		&clp->cl_state) == 0)
2466		nfs4_schedule_state_manager(clp);
2467}
2468
2469void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags,
2470		bool recovery)
2471{
2472	if (!flags)
2473		return;
2474
2475	dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
2476		__func__, clp->cl_hostname, clp->cl_clientid, flags);
2477	/*
2478	 * If we're called from the state manager thread, then assume we're
2479	 * already handling the RECLAIM_NEEDED and/or STATE_REVOKED.
2480	 * Those flags are expected to remain set until we're done
2481	 * recovering (see RFC5661, section 18.46.3).
2482	 */
2483	if (recovery)
2484		goto out_recovery;
2485
2486	if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
2487		nfs41_handle_server_reboot(clp);
2488	if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED))
2489		nfs41_handle_all_state_revoked(clp);
2490	if (flags & (SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
2491			    SEQ4_STATUS_ADMIN_STATE_REVOKED))
2492		nfs41_handle_some_state_revoked(clp);
2493	if (flags & SEQ4_STATUS_LEASE_MOVED)
2494		nfs4_schedule_lease_moved_recovery(clp);
2495	if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
2496		nfs41_handle_recallable_state_revoked(clp);
2497out_recovery:
2498	if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
2499		nfs41_handle_backchannel_fault(clp);
2500	else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
2501				SEQ4_STATUS_CB_PATH_DOWN_SESSION))
2502		nfs41_handle_cb_path_down(clp);
2503}
2504
2505static int nfs4_reset_session(struct nfs_client *clp)
2506{
2507	const struct cred *cred;
2508	int status;
2509
2510	if (!nfs4_has_session(clp))
2511		return 0;
2512	status = nfs4_begin_drain_session(clp);
2513	if (status != 0)
2514		return status;
2515	cred = nfs4_get_clid_cred(clp);
2516	status = nfs4_proc_destroy_session(clp->cl_session, cred);
2517	switch (status) {
2518	case 0:
2519	case -NFS4ERR_BADSESSION:
2520	case -NFS4ERR_DEADSESSION:
2521		break;
2522	case -NFS4ERR_BACK_CHAN_BUSY:
2523	case -NFS4ERR_DELAY:
2524		set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2525		status = 0;
2526		ssleep(1);
2527		goto out;
2528	default:
2529		status = nfs4_recovery_handle_error(clp, status);
2530		goto out;
2531	}
2532
2533	memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
2534	status = nfs4_proc_create_session(clp, cred);
2535	if (status) {
2536		dprintk("%s: session reset failed with status %d for server %s!\n",
2537			__func__, status, clp->cl_hostname);
2538		status = nfs4_handle_reclaim_lease_error(clp, status);
2539		goto out;
2540	}
2541	nfs41_finish_session_reset(clp);
2542	dprintk("%s: session reset was successful for server %s!\n",
2543			__func__, clp->cl_hostname);
2544out:
2545	put_cred(cred);
2546	return status;
2547}
2548
2549static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2550{
2551	const struct cred *cred;
2552	int ret;
2553
2554	if (!nfs4_has_session(clp))
2555		return 0;
2556	ret = nfs4_begin_drain_session(clp);
2557	if (ret != 0)
2558		return ret;
2559	cred = nfs4_get_clid_cred(clp);
2560	ret = nfs4_proc_bind_conn_to_session(clp, cred);
2561	put_cred(cred);
2562	clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2563	switch (ret) {
2564	case 0:
2565		dprintk("%s: bind_conn_to_session was successful for server %s!\n",
2566			__func__, clp->cl_hostname);
2567		break;
2568	case -NFS4ERR_DELAY:
2569		ssleep(1);
2570		set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2571		break;
2572	default:
2573		return nfs4_recovery_handle_error(clp, ret);
2574	}
2575	return 0;
2576}
2577
2578static void nfs4_layoutreturn_any_run(struct nfs_client *clp)
2579{
2580	int iomode = 0;
2581
2582	if (test_and_clear_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &clp->cl_state))
2583		iomode += IOMODE_READ;
2584	if (test_and_clear_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &clp->cl_state))
2585		iomode += IOMODE_RW;
2586	/* Note: IOMODE_READ + IOMODE_RW == IOMODE_ANY */
2587	if (iomode) {
2588		pnfs_layout_return_unused_byclid(clp, iomode);
2589		set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
2590	}
2591}
2592#else /* CONFIG_NFS_V4_1 */
2593static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
2594
2595static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2596{
2597	return 0;
2598}
2599
2600static void nfs4_layoutreturn_any_run(struct nfs_client *clp)
2601{
2602}
2603#endif /* CONFIG_NFS_V4_1 */
2604
2605static void nfs4_state_manager(struct nfs_client *clp)
2606{
2607	unsigned int memflags;
2608	int status = 0;
2609	const char *section = "", *section_sep = "";
2610
2611	/*
2612	 * State recovery can deadlock if the direct reclaim code tries
2613	 * start NFS writeback. So ensure memory allocations are all
2614	 * GFP_NOFS.
2615	 */
2616	memflags = memalloc_nofs_save();
2617
2618	/* Ensure exclusive access to NFSv4 state */
2619	do {
2620		trace_nfs4_state_mgr(clp);
2621		clear_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
2622		if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
2623			section = "purge state";
2624			status = nfs4_purge_lease(clp);
2625			if (status < 0)
2626				goto out_error;
2627			continue;
2628		}
2629
2630		if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
2631			section = "lease expired";
2632			/* We're going to have to re-establish a clientid */
2633			status = nfs4_reclaim_lease(clp);
2634			if (status < 0)
2635				goto out_error;
2636			continue;
2637		}
2638
2639		/* Initialize or reset the session */
2640		if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) {
2641			section = "reset session";
2642			status = nfs4_reset_session(clp);
2643			if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
2644				continue;
2645			if (status < 0)
2646				goto out_error;
2647		}
2648
2649		/* Send BIND_CONN_TO_SESSION */
2650		if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2651				&clp->cl_state)) {
2652			section = "bind conn to session";
2653			status = nfs4_bind_conn_to_session(clp);
2654			if (status < 0)
2655				goto out_error;
2656			continue;
2657		}
2658
2659		if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
2660			section = "check lease";
2661			status = nfs4_check_lease(clp);
2662			if (status < 0)
2663				goto out_error;
2664			continue;
2665		}
2666
2667		if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) {
2668			section = "migration";
2669			status = nfs4_handle_migration(clp);
2670			if (status < 0)
2671				goto out_error;
2672		}
2673
2674		if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) {
2675			section = "lease moved";
2676			status = nfs4_handle_lease_moved(clp);
2677			if (status < 0)
2678				goto out_error;
2679		}
2680
2681		/* First recover reboot state... */
2682		if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
2683			section = "reclaim reboot";
2684			status = nfs4_do_reclaim(clp,
2685				clp->cl_mvops->reboot_recovery_ops);
2686			if (status == -EAGAIN)
2687				continue;
2688			if (status < 0)
2689				goto out_error;
2690			nfs4_state_end_reclaim_reboot(clp);
2691			continue;
2692		}
2693
2694		/* Detect expired delegations... */
2695		if (test_and_clear_bit(NFS4CLNT_DELEGATION_EXPIRED, &clp->cl_state)) {
2696			section = "detect expired delegations";
2697			nfs_reap_expired_delegations(clp);
2698			continue;
2699		}
2700
2701		/* Now recover expired state... */
2702		if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
2703			section = "reclaim nograce";
2704			status = nfs4_do_reclaim(clp,
2705				clp->cl_mvops->nograce_recovery_ops);
2706			if (status == -EAGAIN)
2707				continue;
2708			if (status < 0)
2709				goto out_error;
2710			clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
2711		}
2712
2713		memalloc_nofs_restore(memflags);
2714		nfs4_end_drain_session(clp);
2715		nfs4_clear_state_manager_bit(clp);
2716
2717		if (test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state) &&
2718		    !test_and_set_bit(NFS4CLNT_MANAGER_RUNNING,
2719				      &clp->cl_state)) {
2720			memflags = memalloc_nofs_save();
2721			continue;
2722		}
2723
2724		if (!test_and_set_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state)) {
2725			if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
2726				nfs_client_return_marked_delegations(clp);
2727				set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
2728			}
2729			nfs4_layoutreturn_any_run(clp);
2730			clear_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state);
2731		}
2732
2733		return;
2734
 
 
 
2735	} while (refcount_read(&clp->cl_count) > 1 && !signalled());
2736	goto out_drain;
2737
2738out_error:
2739	if (strlen(section))
2740		section_sep = ": ";
2741	trace_nfs4_state_mgr_failed(clp, section, status);
2742	pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s"
2743			" with error %d\n", section_sep, section,
2744			clp->cl_hostname, -status);
2745	ssleep(1);
2746out_drain:
2747	memalloc_nofs_restore(memflags);
2748	nfs4_end_drain_session(clp);
2749	nfs4_clear_state_manager_bit(clp);
2750}
2751
2752static int nfs4_run_state_manager(void *ptr)
2753{
2754	struct nfs_client *clp = ptr;
2755	struct rpc_clnt *cl = clp->cl_rpcclient;
2756
2757	while (cl != cl->cl_parent)
2758		cl = cl->cl_parent;
2759
2760	allow_signal(SIGKILL);
2761again:
2762	nfs4_state_manager(clp);
2763
2764	if (test_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state) &&
2765	    !test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state)) {
2766		wait_var_event_interruptible(&clp->cl_state,
2767					     test_bit(NFS4CLNT_RUN_MANAGER,
2768						      &clp->cl_state));
2769		if (!atomic_read(&cl->cl_swapper))
2770			clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state);
2771		if (refcount_read(&clp->cl_count) > 1 && !signalled() &&
2772		    !test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state))
2773			goto again;
2774		/* Either no longer a swapper, or were signalled */
2775		clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state);
2776	}
2777
2778	if (refcount_read(&clp->cl_count) > 1 && !signalled() &&
2779	    test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state) &&
2780	    !test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state))
2781		goto again;
2782
2783	nfs_put_client(clp);
2784	module_put_and_kthread_exit(0);
2785	return 0;
2786}