Pileus Git - ~andy/linux/blob - fs/nfs/nfs4state.c

   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/nfs_idmap.h>
  46 #include <linux/kthread.h>
  47 #include <linux/module.h>
  48 #include <linux/random.h>
  49 #include <linux/ratelimit.h>
  50 #include <linux/workqueue.h>
  51 #include <linux/bitops.h>
  52 #include <linux/jiffies.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 "nfs4session.h"
  61 #include "pnfs.h"
  62 #include "netns.h"
  63
  64 #define NFSDBG_FACILITY         NFSDBG_STATE
  65
  66 #define OPENOWNER_POOL_SIZE     8
  67
  68 const nfs4_stateid zero_stateid;
  69 static DEFINE_MUTEX(nfs_clid_init_mutex);
  70
  71 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  72 {
  73         struct nfs4_setclientid_res clid = {
  74                 .clientid = clp->cl_clientid,
  75                 .confirm = clp->cl_confirm,
  76         };
  77         unsigned short port;
  78         int status;
  79         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  80
  81         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
  82                 goto do_confirm;
  83         port = nn->nfs_callback_tcpport;
  84         if (clp->cl_addr.ss_family == AF_INET6)
  85                 port = nn->nfs_callback_tcpport6;
  86
  87         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
  88         if (status != 0)
  89                 goto out;
  90         clp->cl_clientid = clid.clientid;
  91         clp->cl_confirm = clid.confirm;
  92         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  93 do_confirm:
  94         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
  95         if (status != 0)
  96                 goto out;
  97         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  98         nfs4_schedule_state_renewal(clp);
  99 out:
 100         return status;
 101 }
 102
 103 /**
 104  * nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
 105  *
 106  * @clp: nfs_client under test
 107  * @result: OUT: found nfs_client, or clp
 108  * @cred: credential to use for trunking test
 109  *
 110  * Returns zero, a negative errno, or a negative NFS4ERR status.
 111  * If zero is returned, an nfs_client pointer is planted in
 112  * "result".
 113  *
 114  * Note: The returned client may not yet be marked ready.
 115  */
 116 int nfs40_discover_server_trunking(struct nfs_client *clp,
 117                                    struct nfs_client **result,
 118                                    struct rpc_cred *cred)
 119 {
 120         struct nfs4_setclientid_res clid = {
 121                 .clientid = clp->cl_clientid,
 122                 .confirm = clp->cl_confirm,
 123         };
 124         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 125         unsigned short port;
 126         int status;
 127
 128         port = nn->nfs_callback_tcpport;
 129         if (clp->cl_addr.ss_family == AF_INET6)
 130                 port = nn->nfs_callback_tcpport6;
 131
 132         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
 133         if (status != 0)
 134                 goto out;
 135         clp->cl_clientid = clid.clientid;
 136         clp->cl_confirm = clid.confirm;
 137
 138         status = nfs40_walk_client_list(clp, result, cred);
 139         if (status == 0) {
 140                 /* Sustain the lease, even if it's empty.  If the clientid4
 141                  * goes stale it's of no use for trunking discovery. */
 142                 nfs4_schedule_state_renewal(*result);
 143         }
 144 out:
 145         return status;
 146 }
 147
 148 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
 149 {
 150         struct rpc_cred *cred = NULL;
 151
 152         if (clp->cl_machine_cred != NULL)
 153                 cred = get_rpccred(clp->cl_machine_cred);
 154         return cred;
 155 }
 156
 157 static void nfs4_root_machine_cred(struct nfs_client *clp)
 158 {
 159         struct rpc_cred *cred, *new;
 160
 161         new = rpc_lookup_machine_cred(NULL);
 162         spin_lock(&clp->cl_lock);
 163         cred = clp->cl_machine_cred;
 164         clp->cl_machine_cred = new;
 165         spin_unlock(&clp->cl_lock);
 166         if (cred != NULL)
 167                 put_rpccred(cred);
 168 }
 169
 170 static struct rpc_cred *
 171 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 172 {
 173         struct rpc_cred *cred = NULL;
 174         struct nfs4_state_owner *sp;
 175         struct rb_node *pos;
 176
 177         for (pos = rb_first(&server->state_owners);
 178              pos != NULL;
 179              pos = rb_next(pos)) {
 180                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 181                 if (list_empty(&sp->so_states))
 182                         continue;
 183                 cred = get_rpccred(sp->so_cred);
 184                 break;
 185         }
 186         return cred;
 187 }
 188
 189 /**
 190  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
 191  * @clp: client state handle
 192  *
 193  * Returns an rpc_cred with reference count bumped, or NULL.
 194  * Caller must hold clp->cl_lock.
 195  */
 196 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 197 {
 198         struct rpc_cred *cred = NULL;
 199         struct nfs_server *server;
 200
 201         /* Use machine credentials if available */
 202         cred = nfs4_get_machine_cred_locked(clp);
 203         if (cred != NULL)
 204                 goto out;
 205
 206         rcu_read_lock();
 207         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 208                 cred = nfs4_get_renew_cred_server_locked(server);
 209                 if (cred != NULL)
 210                         break;
 211         }
 212         rcu_read_unlock();
 213
 214 out:
 215         return cred;
 216 }
 217
 218 static void nfs4_end_drain_slot_table(struct nfs4_slot_table *tbl)
 219 {
 220         if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
 221                 spin_lock(&tbl->slot_tbl_lock);
 222                 nfs41_wake_slot_table(tbl);
 223                 spin_unlock(&tbl->slot_tbl_lock);
 224         }
 225 }
 226
 227 static void nfs4_end_drain_session(struct nfs_client *clp)
 228 {
 229         struct nfs4_session *ses = clp->cl_session;
 230
 231         if (clp->cl_slot_tbl) {
 232                 nfs4_end_drain_slot_table(clp->cl_slot_tbl);
 233                 return;
 234         }
 235
 236         if (ses != NULL) {
 237                 nfs4_end_drain_slot_table(&ses->bc_slot_table);
 238                 nfs4_end_drain_slot_table(&ses->fc_slot_table);
 239         }
 240 }
 241
 242 static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
 243 {
 244         set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
 245         spin_lock(&tbl->slot_tbl_lock);
 246         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
 247                 reinit_completion(&tbl->complete);
 248                 spin_unlock(&tbl->slot_tbl_lock);
 249                 return wait_for_completion_interruptible(&tbl->complete);
 250         }
 251         spin_unlock(&tbl->slot_tbl_lock);
 252         return 0;
 253 }
 254
 255 static int nfs4_begin_drain_session(struct nfs_client *clp)
 256 {
 257         struct nfs4_session *ses = clp->cl_session;
 258         int ret = 0;
 259
 260         if (clp->cl_slot_tbl)
 261                 return nfs4_drain_slot_tbl(clp->cl_slot_tbl);
 262
 263         /* back channel */
 264         ret = nfs4_drain_slot_tbl(&ses->bc_slot_table);
 265         if (ret)
 266                 return ret;
 267         /* fore channel */
 268         return nfs4_drain_slot_tbl(&ses->fc_slot_table);
 269 }
 270
 271 #if defined(CONFIG_NFS_V4_1)
 272
 273 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 274 {
 275         int status;
 276         struct nfs_fsinfo fsinfo;
 277
 278         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
 279                 nfs4_schedule_state_renewal(clp);
 280                 return 0;
 281         }
 282
 283         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 284         if (status == 0) {
 285                 /* Update lease time and schedule renewal */
 286                 spin_lock(&clp->cl_lock);
 287                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 288                 clp->cl_last_renewal = jiffies;
 289                 spin_unlock(&clp->cl_lock);
 290
 291                 nfs4_schedule_state_renewal(clp);
 292         }
 293
 294         return status;
 295 }
 296
 297 static void nfs41_finish_session_reset(struct nfs_client *clp)
 298 {
 299         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 300         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
 301         /* create_session negotiated new slot table */
 302         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
 303         nfs41_setup_state_renewal(clp);
 304 }
 305
 306 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 307 {
 308         int status;
 309
 310         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 311                 goto do_confirm;
 312         nfs4_begin_drain_session(clp);
 313         status = nfs4_proc_exchange_id(clp, cred);
 314         if (status != 0)
 315                 goto out;
 316         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 317 do_confirm:
 318         status = nfs4_proc_create_session(clp, cred);
 319         if (status != 0)
 320                 goto out;
 321         nfs41_finish_session_reset(clp);
 322         nfs_mark_client_ready(clp, NFS_CS_READY);
 323 out:
 324         return status;
 325 }
 326
 327 /**
 328  * nfs41_discover_server_trunking - Detect server IP address trunking (mv1)
 329  *
 330  * @clp: nfs_client under test
 331  * @result: OUT: found nfs_client, or clp
 332  * @cred: credential to use for trunking test
 333  *
 334  * Returns NFS4_OK, a negative errno, or a negative NFS4ERR status.
 335  * If NFS4_OK is returned, an nfs_client pointer is planted in
 336  * "result".
 337  *
 338  * Note: The returned client may not yet be marked ready.
 339  */
 340 int nfs41_discover_server_trunking(struct nfs_client *clp,
 341                                    struct nfs_client **result,
 342                                    struct rpc_cred *cred)
 343 {
 344         int status;
 345
 346         status = nfs4_proc_exchange_id(clp, cred);
 347         if (status != NFS4_OK)
 348                 return status;
 349         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 350
 351         return nfs41_walk_client_list(clp, result, cred);
 352 }
 353
 354 #endif /* CONFIG_NFS_V4_1 */
 355
 356 /**
 357  * nfs4_get_clid_cred - Acquire credential for a setclientid operation
 358  * @clp: client state handle
 359  *
 360  * Returns an rpc_cred with reference count bumped, or NULL.
 361  */
 362 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp)
 363 {
 364         struct rpc_cred *cred;
 365
 366         spin_lock(&clp->cl_lock);
 367         cred = nfs4_get_machine_cred_locked(clp);
 368         spin_unlock(&clp->cl_lock);
 369         return cred;
 370 }
 371
 372 static struct nfs4_state_owner *
 373 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
 374 {
 375         struct rb_node **p = &server->state_owners.rb_node,
 376                        *parent = NULL;
 377         struct nfs4_state_owner *sp;
 378
 379         while (*p != NULL) {
 380                 parent = *p;
 381                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 382
 383                 if (cred < sp->so_cred)
 384                         p = &parent->rb_left;
 385                 else if (cred > sp->so_cred)
 386                         p = &parent->rb_right;
 387                 else {
 388                         if (!list_empty(&sp->so_lru))
 389                                 list_del_init(&sp->so_lru);
 390                         atomic_inc(&sp->so_count);
 391                         return sp;
 392                 }
 393         }
 394         return NULL;
 395 }
 396
 397 static struct nfs4_state_owner *
 398 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 399 {
 400         struct nfs_server *server = new->so_server;
 401         struct rb_node **p = &server->state_owners.rb_node,
 402                        *parent = NULL;
 403         struct nfs4_state_owner *sp;
 404         int err;
 405
 406         while (*p != NULL) {
 407                 parent = *p;
 408                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 409
 410                 if (new->so_cred < sp->so_cred)
 411                         p = &parent->rb_left;
 412                 else if (new->so_cred > sp->so_cred)
 413                         p = &parent->rb_right;
 414                 else {
 415                         if (!list_empty(&sp->so_lru))
 416                                 list_del_init(&sp->so_lru);
 417                         atomic_inc(&sp->so_count);
 418                         return sp;
 419                 }
 420         }
 421         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
 422         if (err)
 423                 return ERR_PTR(err);
 424         rb_link_node(&new->so_server_node, parent, p);
 425         rb_insert_color(&new->so_server_node, &server->state_owners);
 426         return new;
 427 }
 428
 429 static void
 430 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 431 {
 432         struct nfs_server *server = sp->so_server;
 433
 434         if (!RB_EMPTY_NODE(&sp->so_server_node))
 435                 rb_erase(&sp->so_server_node, &server->state_owners);
 436         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
 437 }
 438
 439 static void
 440 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
 441 {
 442         sc->create_time = ktime_get();
 443         sc->flags = 0;
 444         sc->counter = 0;
 445         spin_lock_init(&sc->lock);
 446         INIT_LIST_HEAD(&sc->list);
 447         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
 448 }
 449
 450 static void
 451 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
 452 {
 453         rpc_destroy_wait_queue(&sc->wait);
 454 }
 455
 456 /*
 457  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 458  * create a new state_owner.
 459  *
 460  */
 461 static struct nfs4_state_owner *
 462 nfs4_alloc_state_owner(struct nfs_server *server,
 463                 struct rpc_cred *cred,
 464                 gfp_t gfp_flags)
 465 {
 466         struct nfs4_state_owner *sp;
 467
 468         sp = kzalloc(sizeof(*sp), gfp_flags);
 469         if (!sp)
 470                 return NULL;
 471         sp->so_server = server;
 472         sp->so_cred = get_rpccred(cred);
 473         spin_lock_init(&sp->so_lock);
 474         INIT_LIST_HEAD(&sp->so_states);
 475         nfs4_init_seqid_counter(&sp->so_seqid);
 476         atomic_set(&sp->so_count, 1);
 477         INIT_LIST_HEAD(&sp->so_lru);
 478         seqcount_init(&sp->so_reclaim_seqcount);
 479         mutex_init(&sp->so_delegreturn_mutex);
 480         return sp;
 481 }
 482
 483 static void
 484 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 485 {
 486         struct rb_node *rb_node = &sp->so_server_node;
 487
 488         if (!RB_EMPTY_NODE(rb_node)) {
 489                 struct nfs_server *server = sp->so_server;
 490                 struct nfs_client *clp = server->nfs_client;
 491
 492                 spin_lock(&clp->cl_lock);
 493                 if (!RB_EMPTY_NODE(rb_node)) {
 494                         rb_erase(rb_node, &server->state_owners);
 495                         RB_CLEAR_NODE(rb_node);
 496                 }
 497                 spin_unlock(&clp->cl_lock);
 498         }
 499 }
 500
 501 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 502 {
 503         nfs4_destroy_seqid_counter(&sp->so_seqid);
 504         put_rpccred(sp->so_cred);
 505         kfree(sp);
 506 }
 507
 508 static void nfs4_gc_state_owners(struct nfs_server *server)
 509 {
 510         struct nfs_client *clp = server->nfs_client;
 511         struct nfs4_state_owner *sp, *tmp;
 512         unsigned long time_min, time_max;
 513         LIST_HEAD(doomed);
 514
 515         spin_lock(&clp->cl_lock);
 516         time_max = jiffies;
 517         time_min = (long)time_max - (long)clp->cl_lease_time;
 518         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 519                 /* NB: LRU is sorted so that oldest is at the head */
 520                 if (time_in_range(sp->so_expires, time_min, time_max))
 521                         break;
 522                 list_move(&sp->so_lru, &doomed);
 523                 nfs4_remove_state_owner_locked(sp);
 524         }
 525         spin_unlock(&clp->cl_lock);
 526
 527         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 528                 list_del(&sp->so_lru);
 529                 nfs4_free_state_owner(sp);
 530         }
 531 }
 532
 533 /**
 534  * nfs4_get_state_owner - Look up a state owner given a credential
 535  * @server: nfs_server to search
 536  * @cred: RPC credential to match
 537  *
 538  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 539  */
 540 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 541                                               struct rpc_cred *cred,
 542                                               gfp_t gfp_flags)
 543 {
 544         struct nfs_client *clp = server->nfs_client;
 545         struct nfs4_state_owner *sp, *new;
 546
 547         spin_lock(&clp->cl_lock);
 548         sp = nfs4_find_state_owner_locked(server, cred);
 549         spin_unlock(&clp->cl_lock);
 550         if (sp != NULL)
 551                 goto out;
 552         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 553         if (new == NULL)
 554                 goto out;
 555         do {
 556                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
 557                         break;
 558                 spin_lock(&clp->cl_lock);
 559                 sp = nfs4_insert_state_owner_locked(new);
 560                 spin_unlock(&clp->cl_lock);
 561         } while (sp == ERR_PTR(-EAGAIN));
 562         if (sp != new)
 563                 nfs4_free_state_owner(new);
 564 out:
 565         nfs4_gc_state_owners(server);
 566         return sp;
 567 }
 568
 569 /**
 570  * nfs4_put_state_owner - Release a nfs4_state_owner
 571  * @sp: state owner data to release
 572  *
 573  * Note that we keep released state owners on an LRU
 574  * list.
 575  * This caches valid state owners so that they can be
 576  * reused, to avoid the OPEN_CONFIRM on minor version 0.
 577  * It also pins the uniquifier of dropped state owners for
 578  * a while, to ensure that those state owner names are
 579  * never reused.
 580  */
 581 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 582 {
 583         struct nfs_server *server = sp->so_server;
 584         struct nfs_client *clp = server->nfs_client;
 585
 586         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 587                 return;
 588
 589         sp->so_expires = jiffies;
 590         list_add_tail(&sp->so_lru, &server->state_owners_lru);
 591         spin_unlock(&clp->cl_lock);
 592 }
 593
 594 /**
 595  * nfs4_purge_state_owners - Release all cached state owners
 596  * @server: nfs_server with cached state owners to release
 597  *
 598  * Called at umount time.  Remaining state owners will be on
 599  * the LRU with ref count of zero.
 600  */
 601 void nfs4_purge_state_owners(struct nfs_server *server)
 602 {
 603         struct nfs_client *clp = server->nfs_client;
 604         struct nfs4_state_owner *sp, *tmp;
 605         LIST_HEAD(doomed);
 606
 607         spin_lock(&clp->cl_lock);
 608         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 609                 list_move(&sp->so_lru, &doomed);
 610                 nfs4_remove_state_owner_locked(sp);
 611         }
 612         spin_unlock(&clp->cl_lock);
 613
 614         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 615                 list_del(&sp->so_lru);
 616                 nfs4_free_state_owner(sp);
 617         }
 618 }
 619
 620 static struct nfs4_state *
 621 nfs4_alloc_open_state(void)
 622 {
 623         struct nfs4_state *state;
 624
 625         state = kzalloc(sizeof(*state), GFP_NOFS);
 626         if (!state)
 627                 return NULL;
 628         atomic_set(&state->count, 1);
 629         INIT_LIST_HEAD(&state->lock_states);
 630         spin_lock_init(&state->state_lock);
 631         seqlock_init(&state->seqlock);
 632         return state;
 633 }
 634
 635 void
 636 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 637 {
 638         if (state->state == fmode)
 639                 return;
 640         /* NB! List reordering - see the reclaim code for why.  */
 641         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 642                 if (fmode & FMODE_WRITE)
 643                         list_move(&state->open_states, &state->owner->so_states);
 644                 else
 645                         list_move_tail(&state->open_states, &state->owner->so_states);
 646         }
 647         state->state = fmode;
 648 }
 649
 650 static struct nfs4_state *
 651 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 652 {
 653         struct nfs_inode *nfsi = NFS_I(inode);
 654         struct nfs4_state *state;
 655
 656         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 657                 if (state->owner != owner)
 658                         continue;
 659                 if (!nfs4_valid_open_stateid(state))
 660                         continue;
 661                 if (atomic_inc_not_zero(&state->count))
 662                         return state;
 663         }
 664         return NULL;
 665 }
 666
 667 static void
 668 nfs4_free_open_state(struct nfs4_state *state)
 669 {
 670         kfree(state);
 671 }
 672
 673 struct nfs4_state *
 674 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 675 {
 676         struct nfs4_state *state, *new;
 677         struct nfs_inode *nfsi = NFS_I(inode);
 678
 679         spin_lock(&inode->i_lock);
 680         state = __nfs4_find_state_byowner(inode, owner);
 681         spin_unlock(&inode->i_lock);
 682         if (state)
 683                 goto out;
 684         new = nfs4_alloc_open_state();
 685         spin_lock(&owner->so_lock);
 686         spin_lock(&inode->i_lock);
 687         state = __nfs4_find_state_byowner(inode, owner);
 688         if (state == NULL && new != NULL) {
 689                 state = new;
 690                 state->owner = owner;
 691                 atomic_inc(&owner->so_count);
 692                 list_add(&state->inode_states, &nfsi->open_states);
 693                 ihold(inode);
 694                 state->inode = inode;
 695                 spin_unlock(&inode->i_lock);
 696                 /* Note: The reclaim code dictates that we add stateless
 697                  * and read-only stateids to the end of the list */
 698                 list_add_tail(&state->open_states, &owner->so_states);
 699                 spin_unlock(&owner->so_lock);
 700         } else {
 701                 spin_unlock(&inode->i_lock);
 702                 spin_unlock(&owner->so_lock);
 703                 if (new)
 704                         nfs4_free_open_state(new);
 705         }
 706 out:
 707         return state;
 708 }
 709
 710 void nfs4_put_open_state(struct nfs4_state *state)
 711 {
 712         struct inode *inode = state->inode;
 713         struct nfs4_state_owner *owner = state->owner;
 714
 715         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 716                 return;
 717         spin_lock(&inode->i_lock);
 718         list_del(&state->inode_states);
 719         list_del(&state->open_states);
 720         spin_unlock(&inode->i_lock);
 721         spin_unlock(&owner->so_lock);
 722         iput(inode);
 723         nfs4_free_open_state(state);
 724         nfs4_put_state_owner(owner);
 725 }
 726
 727 /*
 728  * Close the current file.
 729  */
 730 static void __nfs4_close(struct nfs4_state *state,
 731                 fmode_t fmode, gfp_t gfp_mask, int wait)
 732 {
 733         struct nfs4_state_owner *owner = state->owner;
 734         int call_close = 0;
 735         fmode_t newstate;
 736
 737         atomic_inc(&owner->so_count);
 738         /* Protect against nfs4_find_state() */
 739         spin_lock(&owner->so_lock);
 740         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 741                 case FMODE_READ:
 742                         state->n_rdonly--;
 743                         break;
 744                 case FMODE_WRITE:
 745                         state->n_wronly--;
 746                         break;
 747                 case FMODE_READ|FMODE_WRITE:
 748                         state->n_rdwr--;
 749         }
 750         newstate = FMODE_READ|FMODE_WRITE;
 751         if (state->n_rdwr == 0) {
 752                 if (state->n_rdonly == 0) {
 753                         newstate &= ~FMODE_READ;
 754                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 755                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 756                 }
 757                 if (state->n_wronly == 0) {
 758                         newstate &= ~FMODE_WRITE;
 759                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 760                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 761                 }
 762                 if (newstate == 0)
 763                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 764         }
 765         nfs4_state_set_mode_locked(state, newstate);
 766         spin_unlock(&owner->so_lock);
 767
 768         if (!call_close) {
 769                 nfs4_put_open_state(state);
 770                 nfs4_put_state_owner(owner);
 771         } else
 772                 nfs4_do_close(state, gfp_mask, wait);
 773 }
 774
 775 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 776 {
 777         __nfs4_close(state, fmode, GFP_NOFS, 0);
 778 }
 779
 780 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 781 {
 782         __nfs4_close(state, fmode, GFP_KERNEL, 1);
 783 }
 784
 785 /*
 786  * Search the state->lock_states for an existing lock_owner
 787  * that is compatible with current->files
 788  */
 789 static struct nfs4_lock_state *
 790 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 791 {
 792         struct nfs4_lock_state *pos;
 793         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 794                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
 795                         continue;
 796                 switch (pos->ls_owner.lo_type) {
 797                 case NFS4_POSIX_LOCK_TYPE:
 798                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
 799                                 continue;
 800                         break;
 801                 case NFS4_FLOCK_LOCK_TYPE:
 802                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
 803                                 continue;
 804                 }
 805                 atomic_inc(&pos->ls_count);
 806                 return pos;
 807         }
 808         return NULL;
 809 }
 810
 811 /*
 812  * Return a compatible lock_state. If no initialized lock_state structure
 813  * exists, return an uninitialized one.
 814  *
 815  */
 816 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 817 {
 818         struct nfs4_lock_state *lsp;
 819         struct nfs_server *server = state->owner->so_server;
 820
 821         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 822         if (lsp == NULL)
 823                 return NULL;
 824         nfs4_init_seqid_counter(&lsp->ls_seqid);
 825         atomic_set(&lsp->ls_count, 1);
 826         lsp->ls_state = state;
 827         lsp->ls_owner.lo_type = type;
 828         switch (lsp->ls_owner.lo_type) {
 829         case NFS4_FLOCK_LOCK_TYPE:
 830                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
 831                 break;
 832         case NFS4_POSIX_LOCK_TYPE:
 833                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
 834                 break;
 835         default:
 836                 goto out_free;
 837         }
 838         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
 839         if (lsp->ls_seqid.owner_id < 0)
 840                 goto out_free;
 841         INIT_LIST_HEAD(&lsp->ls_locks);
 842         return lsp;
 843 out_free:
 844         kfree(lsp);
 845         return NULL;
 846 }
 847
 848 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
 849 {
 850         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
 851         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
 852         kfree(lsp);
 853 }
 854
 855 /*
 856  * Return a compatible lock_state. If no initialized lock_state structure
 857  * exists, return an uninitialized one.
 858  *
 859  */
 860 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
 861 {
 862         struct nfs4_lock_state *lsp, *new = NULL;
 863
 864         for(;;) {
 865                 spin_lock(&state->state_lock);
 866                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
 867                 if (lsp != NULL)
 868                         break;
 869                 if (new != NULL) {
 870                         list_add(&new->ls_locks, &state->lock_states);
 871                         set_bit(LK_STATE_IN_USE, &state->flags);
 872                         lsp = new;
 873                         new = NULL;
 874                         break;
 875                 }
 876                 spin_unlock(&state->state_lock);
 877                 new = nfs4_alloc_lock_state(state, owner, pid, type);
 878                 if (new == NULL)
 879                         return NULL;
 880         }
 881         spin_unlock(&state->state_lock);
 882         if (new != NULL)
 883                 nfs4_free_lock_state(state->owner->so_server, new);
 884         return lsp;
 885 }
 886
 887 /*
 888  * Release reference to lock_state, and free it if we see that
 889  * it is no longer in use
 890  */
 891 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 892 {
 893         struct nfs_server *server;
 894         struct nfs4_state *state;
 895
 896         if (lsp == NULL)
 897                 return;
 898         state = lsp->ls_state;
 899         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 900                 return;
 901         list_del(&lsp->ls_locks);
 902         if (list_empty(&state->lock_states))
 903                 clear_bit(LK_STATE_IN_USE, &state->flags);
 904         spin_unlock(&state->state_lock);
 905         server = state->owner->so_server;
 906         if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
 907                 struct nfs_client *clp = server->nfs_client;
 908
 909                 clp->cl_mvops->free_lock_state(server, lsp);
 910         } else
 911                 nfs4_free_lock_state(server, lsp);
 912 }
 913
 914 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 915 {
 916         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 917
 918         dst->fl_u.nfs4_fl.owner = lsp;
 919         atomic_inc(&lsp->ls_count);
 920 }
 921
 922 static void nfs4_fl_release_lock(struct file_lock *fl)
 923 {
 924         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 925 }
 926
 927 static const struct file_lock_operations nfs4_fl_lock_ops = {
 928         .fl_copy_lock = nfs4_fl_copy_lock,
 929         .fl_release_private = nfs4_fl_release_lock,
 930 };
 931
 932 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 933 {
 934         struct nfs4_lock_state *lsp;
 935
 936         if (fl->fl_ops != NULL)
 937                 return 0;
 938         if (fl->fl_flags & FL_POSIX)
 939                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
 940         else if (fl->fl_flags & FL_FLOCK)
 941                 lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
 942                                 NFS4_FLOCK_LOCK_TYPE);
 943         else
 944                 return -EINVAL;
 945         if (lsp == NULL)
 946                 return -ENOMEM;
 947         fl->fl_u.nfs4_fl.owner = lsp;
 948         fl->fl_ops = &nfs4_fl_lock_ops;
 949         return 0;
 950 }
 951
 952 static int nfs4_copy_lock_stateid(nfs4_stateid *dst,
 953                 struct nfs4_state *state,
 954                 const struct nfs_lockowner *lockowner)
 955 {
 956         struct nfs4_lock_state *lsp;
 957         fl_owner_t fl_owner;
 958         pid_t fl_pid;
 959         int ret = -ENOENT;
 960
 961
 962         if (lockowner == NULL)
 963                 goto out;
 964
 965         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 966                 goto out;
 967
 968         fl_owner = lockowner->l_owner;
 969         fl_pid = lockowner->l_pid;
 970         spin_lock(&state->state_lock);
 971         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
 972         if (lsp && test_bit(NFS_LOCK_LOST, &lsp->ls_flags))
 973                 ret = -EIO;
 974         else if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
 975                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
 976                 ret = 0;
 977         }
 978         spin_unlock(&state->state_lock);
 979         nfs4_put_lock_state(lsp);
 980 out:
 981         return ret;
 982 }
 983
 984 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
 985 {
 986         const nfs4_stateid *src;
 987         int seq;
 988
 989         do {
 990                 src = &zero_stateid;
 991                 seq = read_seqbegin(&state->seqlock);
 992                 if (test_bit(NFS_OPEN_STATE, &state->flags))
 993                         src = &state->open_stateid;
 994                 nfs4_stateid_copy(dst, src);
 995         } while (read_seqretry(&state->seqlock, seq));
 996 }
 997
 998 /*
 999  * Byte-range lock aware utility to initialize the stateid of read/write
1000  * requests.
1001  */
1002 int nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
1003                 fmode_t fmode, const struct nfs_lockowner *lockowner)
1004 {
1005         int ret = nfs4_copy_lock_stateid(dst, state, lockowner);
1006         if (ret == -EIO)
1007                 /* A lost lock - don't even consider delegations */
1008                 goto out;
1009         /* returns true if delegation stateid found and copied */
1010         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode)) {
1011                 ret = 0;
1012                 goto out;
1013         }
1014         if (ret != -ENOENT)
1015                 /* nfs4_copy_delegation_stateid() didn't over-write
1016                  * dst, so it still has the lock stateid which we now
1017                  * choose to use.
1018                  */
1019                 goto out;
1020         nfs4_copy_open_stateid(dst, state);
1021         ret = 0;
1022 out:
1023         if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41))
1024                 dst->seqid = 0;
1025         return ret;
1026 }
1027
1028 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
1029 {
1030         struct nfs_seqid *new;
1031
1032         new = kmalloc(sizeof(*new), gfp_mask);
1033         if (new != NULL) {
1034                 new->sequence = counter;
1035                 INIT_LIST_HEAD(&new->list);
1036                 new->task = NULL;
1037         }
1038         return new;
1039 }
1040
1041 void nfs_release_seqid(struct nfs_seqid *seqid)
1042 {
1043         struct nfs_seqid_counter *sequence;
1044
1045         if (list_empty(&seqid->list))
1046                 return;
1047         sequence = seqid->sequence;
1048         spin_lock(&sequence->lock);
1049         list_del_init(&seqid->list);
1050         if (!list_empty(&sequence->list)) {
1051                 struct nfs_seqid *next;
1052
1053                 next = list_first_entry(&sequence->list,
1054                                 struct nfs_seqid, list);
1055                 rpc_wake_up_queued_task(&sequence->wait, next->task);
1056         }
1057         spin_unlock(&sequence->lock);
1058 }
1059
1060 void nfs_free_seqid(struct nfs_seqid *seqid)
1061 {
1062         nfs_release_seqid(seqid);
1063         kfree(seqid);
1064 }
1065
1066 /*
1067  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
1068  * failed with a seqid incrementing error -
1069  * see comments nfs4.h:seqid_mutating_error()
1070  */
1071 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
1072 {
1073         switch (status) {
1074                 case 0:
1075                         break;
1076                 case -NFS4ERR_BAD_SEQID:
1077                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1078                                 return;
1079                         pr_warn_ratelimited("NFS: v4 server returned a bad"
1080                                         " sequence-id error on an"
1081                                         " unconfirmed sequence %p!\n",
1082                                         seqid->sequence);
1083                 case -NFS4ERR_STALE_CLIENTID:
1084                 case -NFS4ERR_STALE_STATEID:
1085                 case -NFS4ERR_BAD_STATEID:
1086                 case -NFS4ERR_BADXDR:
1087                 case -NFS4ERR_RESOURCE:
1088                 case -NFS4ERR_NOFILEHANDLE:
1089                         /* Non-seqid mutating errors */
1090                         return;
1091         };
1092         /*
1093          * Note: no locking needed as we are guaranteed to be first
1094          * on the sequence list
1095          */
1096         seqid->sequence->counter++;
1097 }
1098
1099 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1100 {
1101         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1102                                         struct nfs4_state_owner, so_seqid);
1103         struct nfs_server *server = sp->so_server;
1104
1105         if (status == -NFS4ERR_BAD_SEQID)
1106                 nfs4_drop_state_owner(sp);
1107         if (!nfs4_has_session(server->nfs_client))
1108                 nfs_increment_seqid(status, seqid);
1109 }
1110
1111 /*
1112  * Increment the seqid if the LOCK/LOCKU succeeded, or
1113  * failed with a seqid incrementing error -
1114  * see comments nfs4.h:seqid_mutating_error()
1115  */
1116 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1117 {
1118         nfs_increment_seqid(status, seqid);
1119 }
1120
1121 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1122 {
1123         struct nfs_seqid_counter *sequence = seqid->sequence;
1124         int status = 0;
1125
1126         spin_lock(&sequence->lock);
1127         seqid->task = task;
1128         if (list_empty(&seqid->list))
1129                 list_add_tail(&seqid->list, &sequence->list);
1130         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1131                 goto unlock;
1132         rpc_sleep_on(&sequence->wait, task, NULL);
1133         status = -EAGAIN;
1134 unlock:
1135         spin_unlock(&sequence->lock);
1136         return status;
1137 }
1138
1139 static int nfs4_run_state_manager(void *);
1140
1141 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1142 {
1143         smp_mb__before_clear_bit();
1144         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1145         smp_mb__after_clear_bit();
1146         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1147         rpc_wake_up(&clp->cl_rpcwaitq);
1148 }
1149
1150 /*
1151  * Schedule the nfs_client asynchronous state management routine
1152  */
1153 void nfs4_schedule_state_manager(struct nfs_client *clp)
1154 {
1155         struct task_struct *task;
1156         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1157
1158         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1159                 return;
1160         __module_get(THIS_MODULE);
1161         atomic_inc(&clp->cl_count);
1162
1163         /* The rcu_read_lock() is not strictly necessary, as the state
1164          * manager is the only thread that ever changes the rpc_xprt
1165          * after it's initialized.  At this point, we're single threaded. */
1166         rcu_read_lock();
1167         snprintf(buf, sizeof(buf), "%s-manager",
1168                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1169         rcu_read_unlock();
1170         task = kthread_run(nfs4_run_state_manager, clp, "%s", buf);
1171         if (IS_ERR(task)) {
1172                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1173                         __func__, PTR_ERR(task));
1174                 nfs4_clear_state_manager_bit(clp);
1175                 nfs_put_client(clp);
1176                 module_put(THIS_MODULE);
1177         }
1178 }
1179
1180 /*
1181  * Schedule a lease recovery attempt
1182  */
1183 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1184 {
1185         if (!clp)
1186                 return;
1187         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1188                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1189         dprintk("%s: scheduling lease recovery for server %s\n", __func__,
1190                         clp->cl_hostname);
1191         nfs4_schedule_state_manager(clp);
1192 }
1193 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1194
1195 /**
1196  * nfs4_schedule_migration_recovery - trigger migration recovery
1197  *
1198  * @server: FSID that is migrating
1199  *
1200  * Returns zero if recovery has started, otherwise a negative NFS4ERR
1201  * value is returned.
1202  */
1203 int nfs4_schedule_migration_recovery(const struct nfs_server *server)
1204 {
1205         struct nfs_client *clp = server->nfs_client;
1206
1207         if (server->fh_expire_type != NFS4_FH_PERSISTENT) {
1208                 pr_err("NFS: volatile file handles not supported (server %s)\n",
1209                                 clp->cl_hostname);
1210                 return -NFS4ERR_IO;
1211         }
1212
1213         if (test_bit(NFS_MIG_FAILED, &server->mig_status))
1214                 return -NFS4ERR_IO;
1215
1216         dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n",
1217                         __func__,
1218                         (unsigned long long)server->fsid.major,
1219                         (unsigned long long)server->fsid.minor,
1220                         clp->cl_hostname);
1221
1222         set_bit(NFS_MIG_IN_TRANSITION,
1223                         &((struct nfs_server *)server)->mig_status);
1224         set_bit(NFS4CLNT_MOVED, &clp->cl_state);
1225
1226         nfs4_schedule_state_manager(clp);
1227         return 0;
1228 }
1229 EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
1230
1231 /**
1232  * nfs4_schedule_lease_moved_recovery - start lease-moved recovery
1233  *
1234  * @clp: server to check for moved leases
1235  *
1236  */
1237 void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp)
1238 {
1239         dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n",
1240                 __func__, clp->cl_clientid, clp->cl_hostname);
1241
1242         set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state);
1243         nfs4_schedule_state_manager(clp);
1244 }
1245 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery);
1246
1247 int nfs4_wait_clnt_recover(struct nfs_client *clp)
1248 {
1249         int res;
1250
1251         might_sleep();
1252
1253         atomic_inc(&clp->cl_count);
1254         res = wait_on_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
1255                         nfs_wait_bit_killable, TASK_KILLABLE);
1256         if (res)
1257                 goto out;
1258         if (clp->cl_cons_state < 0)
1259                 res = clp->cl_cons_state;
1260 out:
1261         nfs_put_client(clp);
1262         return res;
1263 }
1264
1265 int nfs4_client_recover_expired_lease(struct nfs_client *clp)
1266 {
1267         unsigned int loop;
1268         int ret;
1269
1270         for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) {
1271                 ret = nfs4_wait_clnt_recover(clp);
1272                 if (ret != 0)
1273                         break;
1274                 if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) &&
1275                     !test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state))
1276                         break;
1277                 nfs4_schedule_state_manager(clp);
1278                 ret = -EIO;
1279         }
1280         return ret;
1281 }
1282
1283 /*
1284  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1285  * @clp: client to process
1286  *
1287  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1288  * resend of the SETCLIENTID and hence re-establish the
1289  * callback channel. Then return all existing delegations.
1290  */
1291 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1292 {
1293         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1294         nfs_expire_all_delegations(clp);
1295         dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__,
1296                         clp->cl_hostname);
1297 }
1298
1299 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1300 {
1301         nfs40_handle_cb_pathdown(clp);
1302         nfs4_schedule_state_manager(clp);
1303 }
1304
1305 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1306 {
1307
1308         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1309         /* Don't recover state that expired before the reboot */
1310         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1311                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1312                 return 0;
1313         }
1314         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1315         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1316         return 1;
1317 }
1318
1319 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1320 {
1321         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1322         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1323         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1324         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1325         return 1;
1326 }
1327
1328 int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1329 {
1330         struct nfs_client *clp = server->nfs_client;
1331
1332         if (!nfs4_valid_open_stateid(state))
1333                 return -EBADF;
1334         nfs4_state_mark_reclaim_nograce(clp, state);
1335         dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
1336                         clp->cl_hostname);
1337         nfs4_schedule_state_manager(clp);
1338         return 0;
1339 }
1340 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1341
1342 void nfs_inode_find_state_and_recover(struct inode *inode,
1343                 const nfs4_stateid *stateid)
1344 {
1345         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1346         struct nfs_inode *nfsi = NFS_I(inode);
1347         struct nfs_open_context *ctx;
1348         struct nfs4_state *state;
1349         bool found = false;
1350
1351         spin_lock(&inode->i_lock);
1352         list_for_each_entry(ctx, &nfsi->open_files, list) {
1353                 state = ctx->state;
1354                 if (state == NULL)
1355                         continue;
1356                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1357                         continue;
1358                 if (!nfs4_stateid_match(&state->stateid, stateid))
1359                         continue;
1360                 nfs4_state_mark_reclaim_nograce(clp, state);
1361                 found = true;
1362         }
1363         spin_unlock(&inode->i_lock);
1364         if (found)
1365                 nfs4_schedule_state_manager(clp);
1366 }
1367
1368 static void nfs4_state_mark_open_context_bad(struct nfs4_state *state)
1369 {
1370         struct inode *inode = state->inode;
1371         struct nfs_inode *nfsi = NFS_I(inode);
1372         struct nfs_open_context *ctx;
1373
1374         spin_lock(&inode->i_lock);
1375         list_for_each_entry(ctx, &nfsi->open_files, list) {
1376                 if (ctx->state != state)
1377                         continue;
1378                 set_bit(NFS_CONTEXT_BAD, &ctx->flags);
1379         }
1380         spin_unlock(&inode->i_lock);
1381 }
1382
1383 static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)
1384 {
1385         set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags);
1386         nfs4_state_mark_open_context_bad(state);
1387 }
1388
1389
1390 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1391 {
1392         struct inode *inode = state->inode;
1393         struct nfs_inode *nfsi = NFS_I(inode);
1394         struct file_lock *fl;
1395         int status = 0;
1396
1397         if (inode->i_flock == NULL)
1398                 return 0;
1399
1400         /* Guard against delegation returns and new lock/unlock calls */
1401         down_write(&nfsi->rwsem);
1402         /* Protect inode->i_flock using the BKL */
1403         spin_lock(&inode->i_lock);
1404         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1405                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1406                         continue;
1407                 if (nfs_file_open_context(fl->fl_file)->state != state)
1408                         continue;
1409                 spin_unlock(&inode->i_lock);
1410                 status = ops->recover_lock(state, fl);
1411                 switch (status) {
1412                         case 0:
1413                                 break;
1414                         case -ESTALE:
1415                         case -NFS4ERR_ADMIN_REVOKED:
1416                         case -NFS4ERR_STALE_STATEID:
1417                         case -NFS4ERR_BAD_STATEID:
1418                         case -NFS4ERR_EXPIRED:
1419                         case -NFS4ERR_NO_GRACE:
1420                         case -NFS4ERR_STALE_CLIENTID:
1421                         case -NFS4ERR_BADSESSION:
1422                         case -NFS4ERR_BADSLOT:
1423                         case -NFS4ERR_BAD_HIGH_SLOT:
1424                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1425                                 goto out;
1426                         default:
1427                                 printk(KERN_ERR "NFS: %s: unhandled error %d\n",
1428                                          __func__, status);
1429                         case -ENOMEM:
1430                         case -NFS4ERR_DENIED:
1431                         case -NFS4ERR_RECLAIM_BAD:
1432                         case -NFS4ERR_RECLAIM_CONFLICT:
1433                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1434                                 status = 0;
1435                 }
1436                 spin_lock(&inode->i_lock);
1437         }
1438         spin_unlock(&inode->i_lock);
1439 out:
1440         up_write(&nfsi->rwsem);
1441         return status;
1442 }
1443
1444 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1445 {
1446         struct nfs4_state *state;
1447         struct nfs4_lock_state *lock;
1448         int status = 0;
1449
1450         /* Note: we rely on the sp->so_states list being ordered
1451          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1452          * states first.
1453          * This is needed to ensure that the server won't give us any
1454          * read delegations that we have to return if, say, we are
1455          * recovering after a network partition or a reboot from a
1456          * server that doesn't support a grace period.
1457          */
1458         spin_lock(&sp->so_lock);
1459         write_seqcount_begin(&sp->so_reclaim_seqcount);
1460 restart:
1461         list_for_each_entry(state, &sp->so_states, open_states) {
1462                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1463                         continue;
1464                 if (!nfs4_valid_open_stateid(state))
1465                         continue;
1466                 if (state->state == 0)
1467                         continue;
1468                 atomic_inc(&state->count);
1469                 spin_unlock(&sp->so_lock);
1470                 status = ops->recover_open(sp, state);
1471                 if (status >= 0) {
1472                         status = nfs4_reclaim_locks(state, ops);
1473                         if (status >= 0) {
1474                                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) {
1475                                         spin_lock(&state->state_lock);
1476                                         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1477                                                 if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
1478                                                         pr_warn_ratelimited("NFS: "
1479                                                                             "%s: Lock reclaim "
1480                                                                             "failed!\n", __func__);
1481                                         }
1482                                         spin_unlock(&state->state_lock);
1483                                 }
1484                                 nfs4_put_open_state(state);
1485                                 spin_lock(&sp->so_lock);
1486                                 goto restart;
1487                         }
1488                 }
1489                 switch (status) {
1490                         default:
1491                                 printk(KERN_ERR "NFS: %s: unhandled error %d\n",
1492                                         __func__, status);
1493                         case -ENOENT:
1494                         case -ENOMEM:
1495                         case -ESTALE:
1496                                 /* Open state on this file cannot be recovered */
1497                                 nfs4_state_mark_recovery_failed(state, status);
1498                                 break;
1499                         case -EAGAIN:
1500                                 ssleep(1);
1501                         case -NFS4ERR_ADMIN_REVOKED:
1502                         case -NFS4ERR_STALE_STATEID:
1503                         case -NFS4ERR_BAD_STATEID:
1504                         case -NFS4ERR_RECLAIM_BAD:
1505                         case -NFS4ERR_RECLAIM_CONFLICT:
1506                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1507                                 break;
1508                         case -NFS4ERR_EXPIRED:
1509                         case -NFS4ERR_NO_GRACE:
1510                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1511                         case -NFS4ERR_STALE_CLIENTID:
1512                         case -NFS4ERR_BADSESSION:
1513                         case -NFS4ERR_BADSLOT:
1514                         case -NFS4ERR_BAD_HIGH_SLOT:
1515                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1516                                 goto out_err;
1517                 }
1518                 nfs4_put_open_state(state);
1519                 spin_lock(&sp->so_lock);
1520                 goto restart;
1521         }
1522         write_seqcount_end(&sp->so_reclaim_seqcount);
1523         spin_unlock(&sp->so_lock);
1524         return 0;
1525 out_err:
1526         nfs4_put_open_state(state);
1527         spin_lock(&sp->so_lock);
1528         write_seqcount_end(&sp->so_reclaim_seqcount);
1529         spin_unlock(&sp->so_lock);
1530         return status;
1531 }
1532
1533 static void nfs4_clear_open_state(struct nfs4_state *state)
1534 {
1535         struct nfs4_lock_state *lock;
1536
1537         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1538         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1539         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1540         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1541         spin_lock(&state->state_lock);
1542         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1543                 lock->ls_seqid.flags = 0;
1544                 clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags);
1545         }
1546         spin_unlock(&state->state_lock);
1547 }
1548
1549 static void nfs4_reset_seqids(struct nfs_server *server,
1550         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1551 {
1552         struct nfs_client *clp = server->nfs_client;
1553         struct nfs4_state_owner *sp;
1554         struct rb_node *pos;
1555         struct nfs4_state *state;
1556
1557         spin_lock(&clp->cl_lock);
1558         for (pos = rb_first(&server->state_owners);
1559              pos != NULL;
1560              pos = rb_next(pos)) {
1561                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1562                 sp->so_seqid.flags = 0;
1563                 spin_lock(&sp->so_lock);
1564                 list_for_each_entry(state, &sp->so_states, open_states) {
1565                         if (mark_reclaim(clp, state))
1566                                 nfs4_clear_open_state(state);
1567                 }
1568                 spin_unlock(&sp->so_lock);
1569         }
1570         spin_unlock(&clp->cl_lock);
1571 }
1572
1573 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1574         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1575 {
1576         struct nfs_server *server;
1577
1578         rcu_read_lock();
1579         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1580                 nfs4_reset_seqids(server, mark_reclaim);
1581         rcu_read_unlock();
1582 }
1583
1584 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1585 {
1586         /* Mark all delegations for reclaim */
1587         nfs_delegation_mark_reclaim(clp);
1588         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1589 }
1590
1591 static void nfs4_reclaim_complete(struct nfs_client *clp,
1592                                  const struct nfs4_state_recovery_ops *ops,
1593                                  struct rpc_cred *cred)
1594 {
1595         /* Notify the server we're done reclaiming our state */
1596         if (ops->reclaim_complete)
1597                 (void)ops->reclaim_complete(clp, cred);
1598 }
1599
1600 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1601 {
1602         struct nfs_client *clp = server->nfs_client;
1603         struct nfs4_state_owner *sp;
1604         struct rb_node *pos;
1605         struct nfs4_state *state;
1606
1607         spin_lock(&clp->cl_lock);
1608         for (pos = rb_first(&server->state_owners);
1609              pos != NULL;
1610              pos = rb_next(pos)) {
1611                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1612                 spin_lock(&sp->so_lock);
1613                 list_for_each_entry(state, &sp->so_states, open_states) {
1614                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1615                                                 &state->flags))
1616                                 continue;
1617                         nfs4_state_mark_reclaim_nograce(clp, state);
1618                 }
1619                 spin_unlock(&sp->so_lock);
1620         }
1621         spin_unlock(&clp->cl_lock);
1622 }
1623
1624 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1625 {
1626         struct nfs_server *server;
1627
1628         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1629                 return 0;
1630
1631         rcu_read_lock();
1632         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1633                 nfs4_clear_reclaim_server(server);
1634         rcu_read_unlock();
1635
1636         nfs_delegation_reap_unclaimed(clp);
1637         return 1;
1638 }
1639
1640 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1641 {
1642         const struct nfs4_state_recovery_ops *ops;
1643         struct rpc_cred *cred;
1644
1645         if (!nfs4_state_clear_reclaim_reboot(clp))
1646                 return;
1647         ops = clp->cl_mvops->reboot_recovery_ops;
1648         cred = nfs4_get_clid_cred(clp);
1649         nfs4_reclaim_complete(clp, ops, cred);
1650         put_rpccred(cred);
1651 }
1652
1653 static void nfs_delegation_clear_all(struct nfs_client *clp)
1654 {
1655         nfs_delegation_mark_reclaim(clp);
1656         nfs_delegation_reap_unclaimed(clp);
1657 }
1658
1659 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1660 {
1661         nfs_delegation_clear_all(clp);
1662         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1663 }
1664
1665 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1666 {
1667         switch (error) {
1668                 case 0:
1669                         break;
1670                 case -NFS4ERR_CB_PATH_DOWN:
1671                         nfs40_handle_cb_pathdown(clp);
1672                         break;
1673                 case -NFS4ERR_NO_GRACE:
1674                         nfs4_state_end_reclaim_reboot(clp);
1675                         break;
1676                 case -NFS4ERR_STALE_CLIENTID:
1677                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1678                         nfs4_state_clear_reclaim_reboot(clp);
1679                         nfs4_state_start_reclaim_reboot(clp);
1680                         break;
1681                 case -NFS4ERR_EXPIRED:
1682                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1683                         nfs4_state_start_reclaim_nograce(clp);
1684                         break;
1685                 case -NFS4ERR_BADSESSION:
1686                 case -NFS4ERR_BADSLOT:
1687                 case -NFS4ERR_BAD_HIGH_SLOT:
1688                 case -NFS4ERR_DEADSESSION:
1689                 case -NFS4ERR_SEQ_FALSE_RETRY:
1690                 case -NFS4ERR_SEQ_MISORDERED:
1691                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1692                         /* Zero session reset errors */
1693                         break;
1694                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1695                         set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1696                         break;
1697                 default:
1698                         dprintk("%s: failed to handle error %d for server %s\n",
1699                                         __func__, error, clp->cl_hostname);
1700                         return error;
1701         }
1702         dprintk("%s: handled error %d for server %s\n", __func__, error,
1703                         clp->cl_hostname);
1704         return 0;
1705 }
1706
1707 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1708 {
1709         struct nfs4_state_owner *sp;
1710         struct nfs_server *server;
1711         struct rb_node *pos;
1712         int status = 0;
1713
1714 restart:
1715         rcu_read_lock();
1716         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1717                 nfs4_purge_state_owners(server);
1718                 spin_lock(&clp->cl_lock);
1719                 for (pos = rb_first(&server->state_owners);
1720                      pos != NULL;
1721                      pos = rb_next(pos)) {
1722                         sp = rb_entry(pos,
1723                                 struct nfs4_state_owner, so_server_node);
1724                         if (!test_and_clear_bit(ops->owner_flag_bit,
1725                                                         &sp->so_flags))
1726                                 continue;
1727                         atomic_inc(&sp->so_count);
1728                         spin_unlock(&clp->cl_lock);
1729                         rcu_read_unlock();
1730
1731                         status = nfs4_reclaim_open_state(sp, ops);
1732                         if (status < 0) {
1733                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1734                                 nfs4_put_state_owner(sp);
1735                                 return nfs4_recovery_handle_error(clp, status);
1736                         }
1737
1738                         nfs4_put_state_owner(sp);
1739                         goto restart;
1740                 }
1741                 spin_unlock(&clp->cl_lock);
1742         }
1743         rcu_read_unlock();
1744         return status;
1745 }
1746
1747 static int nfs4_check_lease(struct nfs_client *clp)
1748 {
1749         struct rpc_cred *cred;
1750         const struct nfs4_state_maintenance_ops *ops =
1751                 clp->cl_mvops->state_renewal_ops;
1752         int status;
1753
1754         /* Is the client already known to have an expired lease? */
1755         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1756                 return 0;
1757         spin_lock(&clp->cl_lock);
1758         cred = ops->get_state_renewal_cred_locked(clp);
1759         spin_unlock(&clp->cl_lock);
1760         if (cred == NULL) {
1761                 cred = nfs4_get_clid_cred(clp);
1762                 status = -ENOKEY;
1763                 if (cred == NULL)
1764                         goto out;
1765         }
1766         status = ops->renew_lease(clp, cred);
1767         put_rpccred(cred);
1768         if (status == -ETIMEDOUT) {
1769                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1770                 return 0;
1771         }
1772 out:
1773         return nfs4_recovery_handle_error(clp, status);
1774 }
1775
1776 /* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors
1777  * and for recoverable errors on EXCHANGE_ID for v4.1
1778  */
1779 static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
1780 {
1781         switch (status) {
1782         case -NFS4ERR_SEQ_MISORDERED:
1783                 if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
1784                         return -ESERVERFAULT;
1785                 /* Lease confirmation error: retry after purging the lease */
1786                 ssleep(1);
1787                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1788                 break;
1789         case -NFS4ERR_STALE_CLIENTID:
1790                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1791                 nfs4_state_clear_reclaim_reboot(clp);
1792                 nfs4_state_start_reclaim_reboot(clp);
1793                 break;
1794         case -NFS4ERR_CLID_INUSE:
1795                 pr_err("NFS: Server %s reports our clientid is in use\n",
1796                         clp->cl_hostname);
1797                 nfs_mark_client_ready(clp, -EPERM);
1798                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1799                 return -EPERM;
1800         case -EACCES:
1801         case -NFS4ERR_DELAY:
1802         case -ETIMEDOUT:
1803         case -EAGAIN:
1804                 ssleep(1);
1805                 break;
1806
1807         case -NFS4ERR_MINOR_VERS_MISMATCH:
1808                 if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1809                         nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
1810                 dprintk("%s: exit with error %d for server %s\n",
1811                                 __func__, -EPROTONOSUPPORT, clp->cl_hostname);
1812                 return -EPROTONOSUPPORT;
1813         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1814                                  * in nfs4_exchange_id */
1815         default:
1816                 dprintk("%s: exit with error %d for server %s\n", __func__,
1817                                 status, clp->cl_hostname);
1818                 return status;
1819         }
1820         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1821         dprintk("%s: handled error %d for server %s\n", __func__, status,
1822                         clp->cl_hostname);
1823         return 0;
1824 }
1825
1826 static int nfs4_establish_lease(struct nfs_client *clp)
1827 {
1828         struct rpc_cred *cred;
1829         const struct nfs4_state_recovery_ops *ops =
1830                 clp->cl_mvops->reboot_recovery_ops;
1831         int status;
1832
1833         cred = nfs4_get_clid_cred(clp);
1834         if (cred == NULL)
1835                 return -ENOENT;
1836         status = ops->establish_clid(clp, cred);
1837         put_rpccred(cred);
1838         if (status != 0)
1839                 return status;
1840         pnfs_destroy_all_layouts(clp);
1841         return 0;
1842 }
1843
1844 /*
1845  * Returns zero or a negative errno.  NFS4ERR values are converted
1846  * to local errno values.
1847  */
1848 static int nfs4_reclaim_lease(struct nfs_client *clp)
1849 {
1850         int status;
1851
1852         status = nfs4_establish_lease(clp);
1853         if (status < 0)
1854                 return nfs4_handle_reclaim_lease_error(clp, status);
1855         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state))
1856                 nfs4_state_start_reclaim_nograce(clp);
1857         if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1858                 set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1859         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1860         clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1861         return 0;
1862 }
1863
1864 static int nfs4_purge_lease(struct nfs_client *clp)
1865 {
1866         int status;
1867
1868         status = nfs4_establish_lease(clp);
1869         if (status < 0)
1870                 return nfs4_handle_reclaim_lease_error(clp, status);
1871         clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1872         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1873         nfs4_state_start_reclaim_nograce(clp);
1874         return 0;
1875 }
1876
1877 /*
1878  * Try remote migration of one FSID from a source server to a
1879  * destination server.  The source server provides a list of
1880  * potential destinations.
1881  *
1882  * Returns zero or a negative NFS4ERR status code.
1883  */
1884 static int nfs4_try_migration(struct nfs_server *server, struct rpc_cred *cred)
1885 {
1886         struct nfs_client *clp = server->nfs_client;
1887         struct nfs4_fs_locations *locations = NULL;
1888         struct inode *inode;
1889         struct page *page;
1890         int status, result;
1891
1892         dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__,
1893                         (unsigned long long)server->fsid.major,
1894                         (unsigned long long)server->fsid.minor,
1895                         clp->cl_hostname);
1896
1897         result = 0;
1898         page = alloc_page(GFP_KERNEL);
1899         locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
1900         if (page == NULL || locations == NULL) {
1901                 dprintk("<-- %s: no memory\n", __func__);
1902                 goto out;
1903         }
1904
1905         inode = server->super->s_root->d_inode;
1906         result = nfs4_proc_get_locations(inode, locations, page, cred);
1907         if (result) {
1908                 dprintk("<-- %s: failed to retrieve fs_locations: %d\n",
1909                         __func__, result);
1910                 goto out;
1911         }
1912
1913         result = -NFS4ERR_NXIO;
1914         if (!(locations->fattr.valid & NFS_ATTR_FATTR_V4_LOCATIONS)) {
1915                 dprintk("<-- %s: No fs_locations data, migration skipped\n",
1916                         __func__);
1917                 goto out;
1918         }
1919
1920         nfs4_begin_drain_session(clp);
1921
1922         status = nfs4_replace_transport(server, locations);
1923         if (status != 0) {
1924                 dprintk("<-- %s: failed to replace transport: %d\n",
1925                         __func__, status);
1926                 goto out;
1927         }
1928
1929         result = 0;
1930         dprintk("<-- %s: migration succeeded\n", __func__);
1931
1932 out:
1933         if (page != NULL)
1934                 __free_page(page);
1935         kfree(locations);
1936         if (result) {
1937                 pr_err("NFS: migration recovery failed (server %s)\n",
1938                                 clp->cl_hostname);
1939                 set_bit(NFS_MIG_FAILED, &server->mig_status);
1940         }
1941         return result;
1942 }
1943
1944 /*
1945  * Returns zero or a negative NFS4ERR status code.
1946  */
1947 static int nfs4_handle_migration(struct nfs_client *clp)
1948 {
1949         const struct nfs4_state_maintenance_ops *ops =
1950                                 clp->cl_mvops->state_renewal_ops;
1951         struct nfs_server *server;
1952         struct rpc_cred *cred;
1953
1954         dprintk("%s: migration reported on \"%s\"\n", __func__,
1955                         clp->cl_hostname);
1956
1957         spin_lock(&clp->cl_lock);
1958         cred = ops->get_state_renewal_cred_locked(clp);
1959         spin_unlock(&clp->cl_lock);
1960         if (cred == NULL)
1961                 return -NFS4ERR_NOENT;
1962
1963         clp->cl_mig_gen++;
1964 restart:
1965         rcu_read_lock();
1966         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1967                 int status;
1968
1969                 if (server->mig_gen == clp->cl_mig_gen)
1970                         continue;
1971                 server->mig_gen = clp->cl_mig_gen;
1972
1973                 if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION,
1974                                                 &server->mig_status))
1975                         continue;
1976
1977                 rcu_read_unlock();
1978                 status = nfs4_try_migration(server, cred);
1979                 if (status < 0) {
1980                         put_rpccred(cred);
1981                         return status;
1982                 }
1983                 goto restart;
1984         }
1985         rcu_read_unlock();
1986         put_rpccred(cred);
1987         return 0;
1988 }
1989
1990 /*
1991  * Test each nfs_server on the clp's cl_superblocks list to see
1992  * if it's moved to another server.  Stop when the server no longer
1993  * returns NFS4ERR_LEASE_MOVED.
1994  */
1995 static int nfs4_handle_lease_moved(struct nfs_client *clp)
1996 {
1997         const struct nfs4_state_maintenance_ops *ops =
1998                                 clp->cl_mvops->state_renewal_ops;
1999         struct nfs_server *server;
2000         struct rpc_cred *cred;
2001
2002         dprintk("%s: lease moved reported on \"%s\"\n", __func__,
2003                         clp->cl_hostname);
2004
2005         spin_lock(&clp->cl_lock);
2006         cred = ops->get_state_renewal_cred_locked(clp);
2007         spin_unlock(&clp->cl_lock);
2008         if (cred == NULL)
2009                 return -NFS4ERR_NOENT;
2010
2011         clp->cl_mig_gen++;
2012 restart:
2013         rcu_read_lock();
2014         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
2015                 struct inode *inode;
2016                 int status;
2017
2018                 if (server->mig_gen == clp->cl_mig_gen)
2019                         continue;
2020                 server->mig_gen = clp->cl_mig_gen;
2021
2022                 rcu_read_unlock();
2023
2024                 inode = server->super->s_root->d_inode;
2025                 status = nfs4_proc_fsid_present(inode, cred);
2026                 if (status != -NFS4ERR_MOVED)
2027                         goto restart;   /* wasn't this one */
2028                 if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED)
2029                         goto restart;   /* there are more */
2030                 goto out;
2031         }
2032         rcu_read_unlock();
2033
2034 out:
2035         put_rpccred(cred);
2036         return 0;
2037 }
2038
2039 /**
2040  * nfs4_discover_server_trunking - Detect server IP address trunking
2041  *
2042  * @clp: nfs_client under test
2043  * @result: OUT: found nfs_client, or clp
2044  *
2045  * Returns zero or a negative errno.  If zero is returned,
2046  * an nfs_client pointer is planted in "result".
2047  *
2048  * Note: since we are invoked in process context, and
2049  * not from inside the state manager, we cannot use
2050  * nfs4_handle_reclaim_lease_error().
2051  */
2052 int nfs4_discover_server_trunking(struct nfs_client *clp,
2053                                   struct nfs_client **result)
2054 {
2055         const struct nfs4_state_recovery_ops *ops =
2056                                 clp->cl_mvops->reboot_recovery_ops;
2057         struct rpc_clnt *clnt;
2058         struct rpc_cred *cred;
2059         int i, status;
2060
2061         dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
2062
2063         clnt = clp->cl_rpcclient;
2064         i = 0;
2065
2066         mutex_lock(&nfs_clid_init_mutex);
2067 again:
2068         status  = -ENOENT;
2069         cred = nfs4_get_clid_cred(clp);
2070         if (cred == NULL)
2071                 goto out_unlock;
2072
2073         status = ops->detect_trunking(clp, result, cred);
2074         put_rpccred(cred);
2075         switch (status) {
2076         case 0:
2077                 break;
2078         case -NFS4ERR_DELAY:
2079         case -ETIMEDOUT:
2080         case -EAGAIN:
2081                 ssleep(1);
2082         case -NFS4ERR_STALE_CLIENTID:
2083                 dprintk("NFS: %s after status %d, retrying\n",
2084                         __func__, status);
2085                 goto again;
2086         case -EACCES:
2087                 if (i++ == 0) {
2088                         nfs4_root_machine_cred(clp);
2089                         goto again;
2090                 }
2091                 if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX)
2092                         break;
2093         case -NFS4ERR_CLID_INUSE:
2094         case -NFS4ERR_WRONGSEC:
2095                 /* No point in retrying if we already used RPC_AUTH_UNIX */
2096                 if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) {
2097                         status = -EPERM;
2098                         break;
2099                 }
2100                 clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
2101                 if (IS_ERR(clnt)) {
2102                         status = PTR_ERR(clnt);
2103                         break;
2104                 }
2105                 /* Note: this is safe because we haven't yet marked the
2106                  * client as ready, so we are the only user of
2107                  * clp->cl_rpcclient
2108                  */
2109                 clnt = xchg(&clp->cl_rpcclient, clnt);
2110                 rpc_shutdown_client(clnt);
2111                 clnt = clp->cl_rpcclient;
2112                 goto again;
2113
2114         case -NFS4ERR_MINOR_VERS_MISMATCH:
2115                 status = -EPROTONOSUPPORT;
2116                 break;
2117
2118         case -EKEYEXPIRED:
2119         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
2120                                  * in nfs4_exchange_id */
2121                 status = -EKEYEXPIRED;
2122                 break;
2123         default:
2124                 pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
2125                                 __func__, status);
2126                 status = -EIO;
2127         }
2128
2129 out_unlock:
2130         mutex_unlock(&nfs_clid_init_mutex);
2131         dprintk("NFS: %s: status = %d\n", __func__, status);
2132         return status;
2133 }
2134
2135 #ifdef CONFIG_NFS_V4_1
2136 void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
2137 {
2138         struct nfs_client *clp = session->clp;
2139
2140         switch (err) {
2141         default:
2142                 set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2143                 break;
2144         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
2145                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2146         }
2147         nfs4_schedule_lease_recovery(clp);
2148 }
2149 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
2150
2151 static void nfs41_ping_server(struct nfs_client *clp)
2152 {
2153         /* Use CHECK_LEASE to ping the server with a SEQUENCE */
2154         set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
2155         nfs4_schedule_state_manager(clp);
2156 }
2157
2158 void nfs41_server_notify_target_slotid_update(struct nfs_client *clp)
2159 {
2160         nfs41_ping_server(clp);
2161 }
2162
2163 void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp)
2164 {
2165         nfs41_ping_server(clp);
2166 }
2167
2168 static void nfs4_reset_all_state(struct nfs_client *clp)
2169 {
2170         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
2171                 set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
2172                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
2173                 nfs4_state_start_reclaim_nograce(clp);
2174                 dprintk("%s: scheduling reset of all state for server %s!\n",
2175                                 __func__, clp->cl_hostname);
2176                 nfs4_schedule_state_manager(clp);
2177         }
2178 }
2179
2180 static void nfs41_handle_server_reboot(struct nfs_client *clp)
2181 {
2182         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
2183                 nfs4_state_start_reclaim_reboot(clp);
2184                 dprintk("%s: server %s rebooted!\n", __func__,
2185                                 clp->cl_hostname);
2186                 nfs4_schedule_state_manager(clp);
2187         }
2188 }
2189
2190 static void nfs41_handle_state_revoked(struct nfs_client *clp)
2191 {
2192         nfs4_reset_all_state(clp);
2193         dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
2194 }
2195
2196 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
2197 {
2198         /* This will need to handle layouts too */
2199         nfs_expire_all_delegations(clp);
2200         dprintk("%s: Recallable state revoked on server %s!\n", __func__,
2201                         clp->cl_hostname);
2202 }
2203
2204 static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
2205 {
2206         nfs_expire_all_delegations(clp);
2207         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
2208                 nfs4_schedule_state_manager(clp);
2209         dprintk("%s: server %s declared a backchannel fault\n", __func__,
2210                         clp->cl_hostname);
2211 }
2212
2213 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
2214 {
2215         if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2216                 &clp->cl_state) == 0)
2217                 nfs4_schedule_state_manager(clp);
2218 }
2219
2220 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
2221 {
2222         if (!flags)
2223                 return;
2224
2225         dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
2226                 __func__, clp->cl_hostname, clp->cl_clientid, flags);
2227
2228         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
2229                 nfs41_handle_server_reboot(clp);
2230         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
2231                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
2232                             SEQ4_STATUS_ADMIN_STATE_REVOKED))
2233                 nfs41_handle_state_revoked(clp);
2234         if (flags & SEQ4_STATUS_LEASE_MOVED)
2235                 nfs4_schedule_lease_moved_recovery(clp);
2236         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
2237                 nfs41_handle_recallable_state_revoked(clp);
2238         if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
2239                 nfs41_handle_backchannel_fault(clp);
2240         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
2241                                 SEQ4_STATUS_CB_PATH_DOWN_SESSION))
2242                 nfs41_handle_cb_path_down(clp);
2243 }
2244
2245 static int nfs4_reset_session(struct nfs_client *clp)
2246 {
2247         struct rpc_cred *cred;
2248         int status;
2249
2250         if (!nfs4_has_session(clp))
2251                 return 0;
2252         nfs4_begin_drain_session(clp);
2253         cred = nfs4_get_clid_cred(clp);
2254         status = nfs4_proc_destroy_session(clp->cl_session, cred);
2255         switch (status) {
2256         case 0:
2257         case -NFS4ERR_BADSESSION:
2258         case -NFS4ERR_DEADSESSION:
2259                 break;
2260         case -NFS4ERR_BACK_CHAN_BUSY:
2261         case -NFS4ERR_DELAY:
2262                 set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2263                 status = 0;
2264                 ssleep(1);
2265                 goto out;
2266         default:
2267                 status = nfs4_recovery_handle_error(clp, status);
2268                 goto out;
2269         }
2270
2271         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
2272         status = nfs4_proc_create_session(clp, cred);
2273         if (status) {
2274                 dprintk("%s: session reset failed with status %d for server %s!\n",
2275                         __func__, status, clp->cl_hostname);
2276                 status = nfs4_handle_reclaim_lease_error(clp, status);
2277                 goto out;
2278         }
2279         nfs41_finish_session_reset(clp);
2280         dprintk("%s: session reset was successful for server %s!\n",
2281                         __func__, clp->cl_hostname);
2282 out:
2283         if (cred)
2284                 put_rpccred(cred);
2285         return status;
2286 }
2287
2288 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2289 {
2290         struct rpc_cred *cred;
2291         int ret;
2292
2293         if (!nfs4_has_session(clp))
2294                 return 0;
2295         nfs4_begin_drain_session(clp);
2296         cred = nfs4_get_clid_cred(clp);
2297         ret = nfs4_proc_bind_conn_to_session(clp, cred);
2298         if (cred)
2299                 put_rpccred(cred);
2300         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2301         switch (ret) {
2302         case 0:
2303                 dprintk("%s: bind_conn_to_session was successful for server %s!\n",
2304                         __func__, clp->cl_hostname);
2305                 break;
2306         case -NFS4ERR_DELAY:
2307                 ssleep(1);
2308                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2309                 break;
2310         default:
2311                 return nfs4_recovery_handle_error(clp, ret);
2312         }
2313         return 0;
2314 }
2315 #else /* CONFIG_NFS_V4_1 */
2316 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
2317
2318 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2319 {
2320         return 0;
2321 }
2322 #endif /* CONFIG_NFS_V4_1 */
2323
2324 static void nfs4_state_manager(struct nfs_client *clp)
2325 {
2326         int status = 0;
2327         const char *section = "", *section_sep = "";
2328
2329         /* Ensure exclusive access to NFSv4 state */
2330         do {
2331                 if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
2332                         section = "purge state";
2333                         status = nfs4_purge_lease(clp);
2334                         if (status < 0)
2335                                 goto out_error;
2336                         continue;
2337                 }
2338
2339                 if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
2340                         section = "lease expired";
2341                         /* We're going to have to re-establish a clientid */
2342                         status = nfs4_reclaim_lease(clp);
2343                         if (status < 0)
2344                                 goto out_error;
2345                         continue;
2346                 }
2347
2348                 /* Initialize or reset the session */
2349                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) {
2350                         section = "reset session";
2351                         status = nfs4_reset_session(clp);
2352                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
2353                                 continue;
2354                         if (status < 0)
2355                                 goto out_error;
2356                 }
2357
2358                 /* Send BIND_CONN_TO_SESSION */
2359                 if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2360                                 &clp->cl_state)) {
2361                         section = "bind conn to session";
2362                         status = nfs4_bind_conn_to_session(clp);
2363                         if (status < 0)
2364                                 goto out_error;
2365                         continue;
2366                 }
2367
2368                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
2369                         section = "check lease";
2370                         status = nfs4_check_lease(clp);
2371                         if (status < 0)
2372                                 goto out_error;
2373                 }
2374
2375                 if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) {
2376                         section = "migration";
2377                         status = nfs4_handle_migration(clp);
2378                         if (status < 0)
2379                                 goto out_error;
2380                 }
2381
2382                 if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) {
2383                         section = "lease moved";
2384                         status = nfs4_handle_lease_moved(clp);
2385                         if (status < 0)
2386                                 goto out_error;
2387                 }
2388
2389                 /* First recover reboot state... */
2390                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
2391                         section = "reclaim reboot";
2392                         status = nfs4_do_reclaim(clp,
2393                                 clp->cl_mvops->reboot_recovery_ops);
2394                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
2395                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
2396                                 continue;
2397                         nfs4_state_end_reclaim_reboot(clp);
2398                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
2399                                 continue;
2400                         if (status < 0)
2401                                 goto out_error;
2402                 }
2403
2404                 /* Now recover expired state... */
2405                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
2406                         section = "reclaim nograce";
2407                         status = nfs4_do_reclaim(clp,
2408                                 clp->cl_mvops->nograce_recovery_ops);
2409                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
2410                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
2411                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
2412                                 continue;
2413                         if (status < 0)
2414                                 goto out_error;
2415                 }
2416
2417                 nfs4_end_drain_session(clp);
2418                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
2419                         nfs_client_return_marked_delegations(clp);
2420                         continue;
2421                 }
2422
2423                 nfs4_clear_state_manager_bit(clp);
2424                 /* Did we race with an attempt to give us more work? */
2425                 if (clp->cl_state == 0)
2426                         break;
2427                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
2428                         break;
2429         } while (atomic_read(&clp->cl_count) > 1);
2430         return;
2431 out_error:
2432         if (strlen(section))
2433                 section_sep = ": ";
2434         pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s"
2435                         " with error %d\n", section_sep, section,
2436                         clp->cl_hostname, -status);
2437         ssleep(1);
2438         nfs4_end_drain_session(clp);
2439         nfs4_clear_state_manager_bit(clp);
2440 }
2441
2442 static int nfs4_run_state_manager(void *ptr)
2443 {
2444         struct nfs_client *clp = ptr;
2445
2446         allow_signal(SIGKILL);
2447         nfs4_state_manager(clp);
2448         nfs_put_client(clp);
2449         module_put_and_exit(0);
2450         return 0;
2451 }
2452
2453 /*
2454  * Local variables:
2455  *  c-basic-offset: 8
2456  * End:
2457  */