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 "nfs4_fs.h"
  55 #include "callback.h"
  56 #include "delegation.h"
  57 #include "internal.h"
  58 #include "pnfs.h"
  59
  60 #define NFSDBG_FACILITY         NFSDBG_STATE
  61
  62 #define OPENOWNER_POOL_SIZE     8
  63
  64 const nfs4_stateid zero_stateid;
  65
  66 static LIST_HEAD(nfs4_clientid_list);
  67
  68 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  69 {
  70         struct nfs4_setclientid_res clid = {
  71                 .clientid = clp->cl_clientid,
  72                 .confirm = clp->cl_confirm,
  73         };
  74         unsigned short port;
  75         int status;
  76
  77         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
  78                 goto do_confirm;
  79         port = nfs_callback_tcpport;
  80         if (clp->cl_addr.ss_family == AF_INET6)
  81                 port = nfs_callback_tcpport6;
  82
  83         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
  84         if (status != 0)
  85                 goto out;
  86         clp->cl_clientid = clid.clientid;
  87         clp->cl_confirm = clid.confirm;
  88         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  89 do_confirm:
  90         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
  91         if (status != 0)
  92                 goto out;
  93         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  94         nfs4_schedule_state_renewal(clp);
  95 out:
  96         return status;
  97 }
  98
  99 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
 100 {
 101         struct rpc_cred *cred = NULL;
 102
 103         if (clp->cl_machine_cred != NULL)
 104                 cred = get_rpccred(clp->cl_machine_cred);
 105         return cred;
 106 }
 107
 108 static void nfs4_clear_machine_cred(struct nfs_client *clp)
 109 {
 110         struct rpc_cred *cred;
 111
 112         spin_lock(&clp->cl_lock);
 113         cred = clp->cl_machine_cred;
 114         clp->cl_machine_cred = NULL;
 115         spin_unlock(&clp->cl_lock);
 116         if (cred != NULL)
 117                 put_rpccred(cred);
 118 }
 119
 120 static struct rpc_cred *
 121 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 122 {
 123         struct rpc_cred *cred = NULL;
 124         struct nfs4_state_owner *sp;
 125         struct rb_node *pos;
 126
 127         for (pos = rb_first(&server->state_owners);
 128              pos != NULL;
 129              pos = rb_next(pos)) {
 130                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 131                 if (list_empty(&sp->so_states))
 132                         continue;
 133                 cred = get_rpccred(sp->so_cred);
 134                 break;
 135         }
 136         return cred;
 137 }
 138
 139 /**
 140  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
 141  * @clp: client state handle
 142  *
 143  * Returns an rpc_cred with reference count bumped, or NULL.
 144  * Caller must hold clp->cl_lock.
 145  */
 146 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 147 {
 148         struct rpc_cred *cred = NULL;
 149         struct nfs_server *server;
 150
 151         /* Use machine credentials if available */
 152         cred = nfs4_get_machine_cred_locked(clp);
 153         if (cred != NULL)
 154                 goto out;
 155
 156         rcu_read_lock();
 157         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 158                 cred = nfs4_get_renew_cred_server_locked(server);
 159                 if (cred != NULL)
 160                         break;
 161         }
 162         rcu_read_unlock();
 163
 164 out:
 165         return cred;
 166 }
 167
 168 #if defined(CONFIG_NFS_V4_1)
 169
 170 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 171 {
 172         int status;
 173         struct nfs_fsinfo fsinfo;
 174
 175         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
 176                 nfs4_schedule_state_renewal(clp);
 177                 return 0;
 178         }
 179
 180         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 181         if (status == 0) {
 182                 /* Update lease time and schedule renewal */
 183                 spin_lock(&clp->cl_lock);
 184                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 185                 clp->cl_last_renewal = jiffies;
 186                 spin_unlock(&clp->cl_lock);
 187
 188                 nfs4_schedule_state_renewal(clp);
 189         }
 190
 191         return status;
 192 }
 193
 194 /*
 195  * Back channel returns NFS4ERR_DELAY for new requests when
 196  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
 197  * is ended.
 198  */
 199 static void nfs4_end_drain_session(struct nfs_client *clp)
 200 {
 201         struct nfs4_session *ses = clp->cl_session;
 202         struct nfs4_slot_table *tbl;
 203         int max_slots;
 204
 205         if (ses == NULL)
 206                 return;
 207         tbl = &ses->fc_slot_table;
 208         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
 209                 spin_lock(&tbl->slot_tbl_lock);
 210                 max_slots = tbl->max_slots;
 211                 while (max_slots--) {
 212                         if (rpc_wake_up_first(&tbl->slot_tbl_waitq,
 213                                                 nfs4_set_task_privileged,
 214                                                 NULL) == NULL)
 215                                 break;
 216                 }
 217                 spin_unlock(&tbl->slot_tbl_lock);
 218         }
 219 }
 220
 221 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
 222 {
 223         spin_lock(&tbl->slot_tbl_lock);
 224         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
 225                 INIT_COMPLETION(tbl->complete);
 226                 spin_unlock(&tbl->slot_tbl_lock);
 227                 return wait_for_completion_interruptible(&tbl->complete);
 228         }
 229         spin_unlock(&tbl->slot_tbl_lock);
 230         return 0;
 231 }
 232
 233 static int nfs4_begin_drain_session(struct nfs_client *clp)
 234 {
 235         struct nfs4_session *ses = clp->cl_session;
 236         int ret = 0;
 237
 238         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
 239         /* back channel */
 240         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
 241         if (ret)
 242                 return ret;
 243         /* fore channel */
 244         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
 245 }
 246
 247 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 248 {
 249         int status;
 250
 251         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 252                 goto do_confirm;
 253         nfs4_begin_drain_session(clp);
 254         status = nfs4_proc_exchange_id(clp, cred);
 255         if (status != 0)
 256                 goto out;
 257         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 258 do_confirm:
 259         status = nfs4_proc_create_session(clp, cred);
 260         if (status != 0)
 261                 goto out;
 262         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 263         nfs41_setup_state_renewal(clp);
 264         nfs_mark_client_ready(clp, NFS_CS_READY);
 265 out:
 266         return status;
 267 }
 268
 269 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 270 {
 271         struct rpc_cred *cred;
 272
 273         spin_lock(&clp->cl_lock);
 274         cred = nfs4_get_machine_cred_locked(clp);
 275         spin_unlock(&clp->cl_lock);
 276         return cred;
 277 }
 278
 279 #endif /* CONFIG_NFS_V4_1 */
 280
 281 static struct rpc_cred *
 282 nfs4_get_setclientid_cred_server(struct nfs_server *server)
 283 {
 284         struct nfs_client *clp = server->nfs_client;
 285         struct rpc_cred *cred = NULL;
 286         struct nfs4_state_owner *sp;
 287         struct rb_node *pos;
 288
 289         spin_lock(&clp->cl_lock);
 290         pos = rb_first(&server->state_owners);
 291         if (pos != NULL) {
 292                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 293                 cred = get_rpccred(sp->so_cred);
 294         }
 295         spin_unlock(&clp->cl_lock);
 296         return cred;
 297 }
 298
 299 /**
 300  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
 301  * @clp: client state handle
 302  *
 303  * Returns an rpc_cred with reference count bumped, or NULL.
 304  */
 305 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 306 {
 307         struct nfs_server *server;
 308         struct rpc_cred *cred;
 309
 310         spin_lock(&clp->cl_lock);
 311         cred = nfs4_get_machine_cred_locked(clp);
 312         spin_unlock(&clp->cl_lock);
 313         if (cred != NULL)
 314                 goto out;
 315
 316         rcu_read_lock();
 317         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 318                 cred = nfs4_get_setclientid_cred_server(server);
 319                 if (cred != NULL)
 320                         break;
 321         }
 322         rcu_read_unlock();
 323
 324 out:
 325         return cred;
 326 }
 327
 328 static struct nfs4_state_owner *
 329 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
 330 {
 331         struct rb_node **p = &server->state_owners.rb_node,
 332                        *parent = NULL;
 333         struct nfs4_state_owner *sp;
 334
 335         while (*p != NULL) {
 336                 parent = *p;
 337                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 338
 339                 if (cred < sp->so_cred)
 340                         p = &parent->rb_left;
 341                 else if (cred > sp->so_cred)
 342                         p = &parent->rb_right;
 343                 else {
 344                         if (!list_empty(&sp->so_lru))
 345                                 list_del_init(&sp->so_lru);
 346                         atomic_inc(&sp->so_count);
 347                         return sp;
 348                 }
 349         }
 350         return NULL;
 351 }
 352
 353 static struct nfs4_state_owner *
 354 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 355 {
 356         struct nfs_server *server = new->so_server;
 357         struct rb_node **p = &server->state_owners.rb_node,
 358                        *parent = NULL;
 359         struct nfs4_state_owner *sp;
 360         int err;
 361
 362         while (*p != NULL) {
 363                 parent = *p;
 364                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 365
 366                 if (new->so_cred < sp->so_cred)
 367                         p = &parent->rb_left;
 368                 else if (new->so_cred > sp->so_cred)
 369                         p = &parent->rb_right;
 370                 else {
 371                         if (!list_empty(&sp->so_lru))
 372                                 list_del_init(&sp->so_lru);
 373                         atomic_inc(&sp->so_count);
 374                         return sp;
 375                 }
 376         }
 377         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
 378         if (err)
 379                 return ERR_PTR(err);
 380         rb_link_node(&new->so_server_node, parent, p);
 381         rb_insert_color(&new->so_server_node, &server->state_owners);
 382         return new;
 383 }
 384
 385 static void
 386 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 387 {
 388         struct nfs_server *server = sp->so_server;
 389
 390         if (!RB_EMPTY_NODE(&sp->so_server_node))
 391                 rb_erase(&sp->so_server_node, &server->state_owners);
 392         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
 393 }
 394
 395 static void
 396 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
 397 {
 398         sc->create_time = ktime_get();
 399         sc->flags = 0;
 400         sc->counter = 0;
 401         spin_lock_init(&sc->lock);
 402         INIT_LIST_HEAD(&sc->list);
 403         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
 404 }
 405
 406 static void
 407 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
 408 {
 409         rpc_destroy_wait_queue(&sc->wait);
 410 }
 411
 412 /*
 413  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 414  * create a new state_owner.
 415  *
 416  */
 417 static struct nfs4_state_owner *
 418 nfs4_alloc_state_owner(struct nfs_server *server,
 419                 struct rpc_cred *cred,
 420                 gfp_t gfp_flags)
 421 {
 422         struct nfs4_state_owner *sp;
 423
 424         sp = kzalloc(sizeof(*sp), gfp_flags);
 425         if (!sp)
 426                 return NULL;
 427         sp->so_server = server;
 428         sp->so_cred = get_rpccred(cred);
 429         spin_lock_init(&sp->so_lock);
 430         INIT_LIST_HEAD(&sp->so_states);
 431         nfs4_init_seqid_counter(&sp->so_seqid);
 432         atomic_set(&sp->so_count, 1);
 433         INIT_LIST_HEAD(&sp->so_lru);
 434         return sp;
 435 }
 436
 437 static void
 438 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 439 {
 440         struct rb_node *rb_node = &sp->so_server_node;
 441
 442         if (!RB_EMPTY_NODE(rb_node)) {
 443                 struct nfs_server *server = sp->so_server;
 444                 struct nfs_client *clp = server->nfs_client;
 445
 446                 spin_lock(&clp->cl_lock);
 447                 if (!RB_EMPTY_NODE(rb_node)) {
 448                         rb_erase(rb_node, &server->state_owners);
 449                         RB_CLEAR_NODE(rb_node);
 450                 }
 451                 spin_unlock(&clp->cl_lock);
 452         }
 453 }
 454
 455 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 456 {
 457         nfs4_destroy_seqid_counter(&sp->so_seqid);
 458         put_rpccred(sp->so_cred);
 459         kfree(sp);
 460 }
 461
 462 static void nfs4_gc_state_owners(struct nfs_server *server)
 463 {
 464         struct nfs_client *clp = server->nfs_client;
 465         struct nfs4_state_owner *sp, *tmp;
 466         unsigned long time_min, time_max;
 467         LIST_HEAD(doomed);
 468
 469         spin_lock(&clp->cl_lock);
 470         time_max = jiffies;
 471         time_min = (long)time_max - (long)clp->cl_lease_time;
 472         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 473                 /* NB: LRU is sorted so that oldest is at the head */
 474                 if (time_in_range(sp->so_expires, time_min, time_max))
 475                         break;
 476                 list_move(&sp->so_lru, &doomed);
 477                 nfs4_remove_state_owner_locked(sp);
 478         }
 479         spin_unlock(&clp->cl_lock);
 480
 481         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 482                 list_del(&sp->so_lru);
 483                 nfs4_free_state_owner(sp);
 484         }
 485 }
 486
 487 /**
 488  * nfs4_get_state_owner - Look up a state owner given a credential
 489  * @server: nfs_server to search
 490  * @cred: RPC credential to match
 491  *
 492  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 493  */
 494 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 495                                               struct rpc_cred *cred,
 496                                               gfp_t gfp_flags)
 497 {
 498         struct nfs_client *clp = server->nfs_client;
 499         struct nfs4_state_owner *sp, *new;
 500
 501         spin_lock(&clp->cl_lock);
 502         sp = nfs4_find_state_owner_locked(server, cred);
 503         spin_unlock(&clp->cl_lock);
 504         if (sp != NULL)
 505                 goto out;
 506         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 507         if (new == NULL)
 508                 goto out;
 509         do {
 510                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
 511                         break;
 512                 spin_lock(&clp->cl_lock);
 513                 sp = nfs4_insert_state_owner_locked(new);
 514                 spin_unlock(&clp->cl_lock);
 515         } while (sp == ERR_PTR(-EAGAIN));
 516         if (sp != new)
 517                 nfs4_free_state_owner(new);
 518 out:
 519         nfs4_gc_state_owners(server);
 520         return sp;
 521 }
 522
 523 /**
 524  * nfs4_put_state_owner - Release a nfs4_state_owner
 525  * @sp: state owner data to release
 526  *
 527  * Note that we keep released state owners on an LRU
 528  * list.
 529  * This caches valid state owners so that they can be
 530  * reused, to avoid the OPEN_CONFIRM on minor version 0.
 531  * It also pins the uniquifier of dropped state owners for
 532  * a while, to ensure that those state owner names are
 533  * never reused.
 534  */
 535 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 536 {
 537         struct nfs_server *server = sp->so_server;
 538         struct nfs_client *clp = server->nfs_client;
 539
 540         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 541                 return;
 542
 543         sp->so_expires = jiffies;
 544         list_add_tail(&sp->so_lru, &server->state_owners_lru);
 545         spin_unlock(&clp->cl_lock);
 546 }
 547
 548 /**
 549  * nfs4_purge_state_owners - Release all cached state owners
 550  * @server: nfs_server with cached state owners to release
 551  *
 552  * Called at umount time.  Remaining state owners will be on
 553  * the LRU with ref count of zero.
 554  */
 555 void nfs4_purge_state_owners(struct nfs_server *server)
 556 {
 557         struct nfs_client *clp = server->nfs_client;
 558         struct nfs4_state_owner *sp, *tmp;
 559         LIST_HEAD(doomed);
 560
 561         spin_lock(&clp->cl_lock);
 562         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 563                 list_move(&sp->so_lru, &doomed);
 564                 nfs4_remove_state_owner_locked(sp);
 565         }
 566         spin_unlock(&clp->cl_lock);
 567
 568         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 569                 list_del(&sp->so_lru);
 570                 nfs4_free_state_owner(sp);
 571         }
 572 }
 573
 574 static struct nfs4_state *
 575 nfs4_alloc_open_state(void)
 576 {
 577         struct nfs4_state *state;
 578
 579         state = kzalloc(sizeof(*state), GFP_NOFS);
 580         if (!state)
 581                 return NULL;
 582         atomic_set(&state->count, 1);
 583         INIT_LIST_HEAD(&state->lock_states);
 584         spin_lock_init(&state->state_lock);
 585         seqlock_init(&state->seqlock);
 586         return state;
 587 }
 588
 589 void
 590 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 591 {
 592         if (state->state == fmode)
 593                 return;
 594         /* NB! List reordering - see the reclaim code for why.  */
 595         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 596                 if (fmode & FMODE_WRITE)
 597                         list_move(&state->open_states, &state->owner->so_states);
 598                 else
 599                         list_move_tail(&state->open_states, &state->owner->so_states);
 600         }
 601         state->state = fmode;
 602 }
 603
 604 static struct nfs4_state *
 605 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 606 {
 607         struct nfs_inode *nfsi = NFS_I(inode);
 608         struct nfs4_state *state;
 609
 610         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 611                 if (state->owner != owner)
 612                         continue;
 613                 if (atomic_inc_not_zero(&state->count))
 614                         return state;
 615         }
 616         return NULL;
 617 }
 618
 619 static void
 620 nfs4_free_open_state(struct nfs4_state *state)
 621 {
 622         kfree(state);
 623 }
 624
 625 struct nfs4_state *
 626 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 627 {
 628         struct nfs4_state *state, *new;
 629         struct nfs_inode *nfsi = NFS_I(inode);
 630
 631         spin_lock(&inode->i_lock);
 632         state = __nfs4_find_state_byowner(inode, owner);
 633         spin_unlock(&inode->i_lock);
 634         if (state)
 635                 goto out;
 636         new = nfs4_alloc_open_state();
 637         spin_lock(&owner->so_lock);
 638         spin_lock(&inode->i_lock);
 639         state = __nfs4_find_state_byowner(inode, owner);
 640         if (state == NULL && new != NULL) {
 641                 state = new;
 642                 state->owner = owner;
 643                 atomic_inc(&owner->so_count);
 644                 list_add(&state->inode_states, &nfsi->open_states);
 645                 ihold(inode);
 646                 state->inode = inode;
 647                 spin_unlock(&inode->i_lock);
 648                 /* Note: The reclaim code dictates that we add stateless
 649                  * and read-only stateids to the end of the list */
 650                 list_add_tail(&state->open_states, &owner->so_states);
 651                 spin_unlock(&owner->so_lock);
 652         } else {
 653                 spin_unlock(&inode->i_lock);
 654                 spin_unlock(&owner->so_lock);
 655                 if (new)
 656                         nfs4_free_open_state(new);
 657         }
 658 out:
 659         return state;
 660 }
 661
 662 void nfs4_put_open_state(struct nfs4_state *state)
 663 {
 664         struct inode *inode = state->inode;
 665         struct nfs4_state_owner *owner = state->owner;
 666
 667         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 668                 return;
 669         spin_lock(&inode->i_lock);
 670         list_del(&state->inode_states);
 671         list_del(&state->open_states);
 672         spin_unlock(&inode->i_lock);
 673         spin_unlock(&owner->so_lock);
 674         iput(inode);
 675         nfs4_free_open_state(state);
 676         nfs4_put_state_owner(owner);
 677 }
 678
 679 /*
 680  * Close the current file.
 681  */
 682 static void __nfs4_close(struct nfs4_state *state,
 683                 fmode_t fmode, gfp_t gfp_mask, int wait)
 684 {
 685         struct nfs4_state_owner *owner = state->owner;
 686         int call_close = 0;
 687         fmode_t newstate;
 688
 689         atomic_inc(&owner->so_count);
 690         /* Protect against nfs4_find_state() */
 691         spin_lock(&owner->so_lock);
 692         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 693                 case FMODE_READ:
 694                         state->n_rdonly--;
 695                         break;
 696                 case FMODE_WRITE:
 697                         state->n_wronly--;
 698                         break;
 699                 case FMODE_READ|FMODE_WRITE:
 700                         state->n_rdwr--;
 701         }
 702         newstate = FMODE_READ|FMODE_WRITE;
 703         if (state->n_rdwr == 0) {
 704                 if (state->n_rdonly == 0) {
 705                         newstate &= ~FMODE_READ;
 706                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 707                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 708                 }
 709                 if (state->n_wronly == 0) {
 710                         newstate &= ~FMODE_WRITE;
 711                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 712                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 713                 }
 714                 if (newstate == 0)
 715                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 716         }
 717         nfs4_state_set_mode_locked(state, newstate);
 718         spin_unlock(&owner->so_lock);
 719
 720         if (!call_close) {
 721                 nfs4_put_open_state(state);
 722                 nfs4_put_state_owner(owner);
 723         } else {
 724                 bool roc = pnfs_roc(state->inode);
 725
 726                 nfs4_do_close(state, gfp_mask, wait, roc);
 727         }
 728 }
 729
 730 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 731 {
 732         __nfs4_close(state, fmode, GFP_NOFS, 0);
 733 }
 734
 735 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 736 {
 737         __nfs4_close(state, fmode, GFP_KERNEL, 1);
 738 }
 739
 740 /*
 741  * Search the state->lock_states for an existing lock_owner
 742  * that is compatible with current->files
 743  */
 744 static struct nfs4_lock_state *
 745 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 746 {
 747         struct nfs4_lock_state *pos;
 748         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 749                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
 750                         continue;
 751                 switch (pos->ls_owner.lo_type) {
 752                 case NFS4_POSIX_LOCK_TYPE:
 753                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
 754                                 continue;
 755                         break;
 756                 case NFS4_FLOCK_LOCK_TYPE:
 757                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
 758                                 continue;
 759                 }
 760                 atomic_inc(&pos->ls_count);
 761                 return pos;
 762         }
 763         return NULL;
 764 }
 765
 766 /*
 767  * Return a compatible lock_state. If no initialized lock_state structure
 768  * exists, return an uninitialized one.
 769  *
 770  */
 771 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)
 772 {
 773         struct nfs4_lock_state *lsp;
 774         struct nfs_server *server = state->owner->so_server;
 775
 776         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 777         if (lsp == NULL)
 778                 return NULL;
 779         nfs4_init_seqid_counter(&lsp->ls_seqid);
 780         atomic_set(&lsp->ls_count, 1);
 781         lsp->ls_state = state;
 782         lsp->ls_owner.lo_type = type;
 783         switch (lsp->ls_owner.lo_type) {
 784         case NFS4_FLOCK_LOCK_TYPE:
 785                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
 786                 break;
 787         case NFS4_POSIX_LOCK_TYPE:
 788                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
 789                 break;
 790         default:
 791                 goto out_free;
 792         }
 793         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
 794         if (lsp->ls_seqid.owner_id < 0)
 795                 goto out_free;
 796         INIT_LIST_HEAD(&lsp->ls_locks);
 797         return lsp;
 798 out_free:
 799         kfree(lsp);
 800         return NULL;
 801 }
 802
 803 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
 804 {
 805         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
 806         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
 807         kfree(lsp);
 808 }
 809
 810 /*
 811  * Return a compatible lock_state. If no initialized lock_state structure
 812  * exists, return an uninitialized one.
 813  *
 814  */
 815 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
 816 {
 817         struct nfs4_lock_state *lsp, *new = NULL;
 818
 819         for(;;) {
 820                 spin_lock(&state->state_lock);
 821                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
 822                 if (lsp != NULL)
 823                         break;
 824                 if (new != NULL) {
 825                         list_add(&new->ls_locks, &state->lock_states);
 826                         set_bit(LK_STATE_IN_USE, &state->flags);
 827                         lsp = new;
 828                         new = NULL;
 829                         break;
 830                 }
 831                 spin_unlock(&state->state_lock);
 832                 new = nfs4_alloc_lock_state(state, owner, pid, type);
 833                 if (new == NULL)
 834                         return NULL;
 835         }
 836         spin_unlock(&state->state_lock);
 837         if (new != NULL)
 838                 nfs4_free_lock_state(state->owner->so_server, new);
 839         return lsp;
 840 }
 841
 842 /*
 843  * Release reference to lock_state, and free it if we see that
 844  * it is no longer in use
 845  */
 846 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 847 {
 848         struct nfs4_state *state;
 849
 850         if (lsp == NULL)
 851                 return;
 852         state = lsp->ls_state;
 853         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 854                 return;
 855         list_del(&lsp->ls_locks);
 856         if (list_empty(&state->lock_states))
 857                 clear_bit(LK_STATE_IN_USE, &state->flags);
 858         spin_unlock(&state->state_lock);
 859         if (lsp->ls_flags & NFS_LOCK_INITIALIZED) {
 860                 if (nfs4_release_lockowner(lsp) == 0)
 861                         return;
 862         }
 863         nfs4_free_lock_state(lsp->ls_state->owner->so_server, lsp);
 864 }
 865
 866 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 867 {
 868         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 869
 870         dst->fl_u.nfs4_fl.owner = lsp;
 871         atomic_inc(&lsp->ls_count);
 872 }
 873
 874 static void nfs4_fl_release_lock(struct file_lock *fl)
 875 {
 876         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 877 }
 878
 879 static const struct file_lock_operations nfs4_fl_lock_ops = {
 880         .fl_copy_lock = nfs4_fl_copy_lock,
 881         .fl_release_private = nfs4_fl_release_lock,
 882 };
 883
 884 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 885 {
 886         struct nfs4_lock_state *lsp;
 887
 888         if (fl->fl_ops != NULL)
 889                 return 0;
 890         if (fl->fl_flags & FL_POSIX)
 891                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
 892         else if (fl->fl_flags & FL_FLOCK)
 893                 lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
 894                                 NFS4_FLOCK_LOCK_TYPE);
 895         else
 896                 return -EINVAL;
 897         if (lsp == NULL)
 898                 return -ENOMEM;
 899         fl->fl_u.nfs4_fl.owner = lsp;
 900         fl->fl_ops = &nfs4_fl_lock_ops;
 901         return 0;
 902 }
 903
 904 static bool nfs4_copy_lock_stateid(nfs4_stateid *dst, struct nfs4_state *state,
 905                 fl_owner_t fl_owner, pid_t fl_pid)
 906 {
 907         struct nfs4_lock_state *lsp;
 908         bool ret = false;
 909
 910         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 911                 goto out;
 912
 913         spin_lock(&state->state_lock);
 914         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
 915         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0) {
 916                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
 917                 ret = true;
 918         }
 919         spin_unlock(&state->state_lock);
 920         nfs4_put_lock_state(lsp);
 921 out:
 922         return ret;
 923 }
 924
 925 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
 926 {
 927         int seq;
 928
 929         do {
 930                 seq = read_seqbegin(&state->seqlock);
 931                 nfs4_stateid_copy(dst, &state->stateid);
 932         } while (read_seqretry(&state->seqlock, seq));
 933 }
 934
 935 /*
 936  * Byte-range lock aware utility to initialize the stateid of read/write
 937  * requests.
 938  */
 939 void nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
 940                 fmode_t fmode, fl_owner_t fl_owner, pid_t fl_pid)
 941 {
 942         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
 943                 return;
 944         if (nfs4_copy_lock_stateid(dst, state, fl_owner, fl_pid))
 945                 return;
 946         nfs4_copy_open_stateid(dst, state);
 947 }
 948
 949 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
 950 {
 951         struct nfs_seqid *new;
 952
 953         new = kmalloc(sizeof(*new), gfp_mask);
 954         if (new != NULL) {
 955                 new->sequence = counter;
 956                 INIT_LIST_HEAD(&new->list);
 957                 new->task = NULL;
 958         }
 959         return new;
 960 }
 961
 962 void nfs_release_seqid(struct nfs_seqid *seqid)
 963 {
 964         struct nfs_seqid_counter *sequence;
 965
 966         if (list_empty(&seqid->list))
 967                 return;
 968         sequence = seqid->sequence;
 969         spin_lock(&sequence->lock);
 970         list_del_init(&seqid->list);
 971         if (!list_empty(&sequence->list)) {
 972                 struct nfs_seqid *next;
 973
 974                 next = list_first_entry(&sequence->list,
 975                                 struct nfs_seqid, list);
 976                 rpc_wake_up_queued_task(&sequence->wait, next->task);
 977         }
 978         spin_unlock(&sequence->lock);
 979 }
 980
 981 void nfs_free_seqid(struct nfs_seqid *seqid)
 982 {
 983         nfs_release_seqid(seqid);
 984         kfree(seqid);
 985 }
 986
 987 /*
 988  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 989  * failed with a seqid incrementing error -
 990  * see comments nfs_fs.h:seqid_mutating_error()
 991  */
 992 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 993 {
 994         BUG_ON(list_first_entry(&seqid->sequence->list, struct nfs_seqid, list) != seqid);
 995         switch (status) {
 996                 case 0:
 997                         break;
 998                 case -NFS4ERR_BAD_SEQID:
 999                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1000                                 return;
1001                         pr_warn_ratelimited("NFS: v4 server returned a bad"
1002                                         " sequence-id error on an"
1003                                         " unconfirmed sequence %p!\n",
1004                                         seqid->sequence);
1005                 case -NFS4ERR_STALE_CLIENTID:
1006                 case -NFS4ERR_STALE_STATEID:
1007                 case -NFS4ERR_BAD_STATEID:
1008                 case -NFS4ERR_BADXDR:
1009                 case -NFS4ERR_RESOURCE:
1010                 case -NFS4ERR_NOFILEHANDLE:
1011                         /* Non-seqid mutating errors */
1012                         return;
1013         };
1014         /*
1015          * Note: no locking needed as we are guaranteed to be first
1016          * on the sequence list
1017          */
1018         seqid->sequence->counter++;
1019 }
1020
1021 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1022 {
1023         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1024                                         struct nfs4_state_owner, so_seqid);
1025         struct nfs_server *server = sp->so_server;
1026
1027         if (status == -NFS4ERR_BAD_SEQID)
1028                 nfs4_drop_state_owner(sp);
1029         if (!nfs4_has_session(server->nfs_client))
1030                 nfs_increment_seqid(status, seqid);
1031 }
1032
1033 /*
1034  * Increment the seqid if the LOCK/LOCKU succeeded, or
1035  * failed with a seqid incrementing error -
1036  * see comments nfs_fs.h:seqid_mutating_error()
1037  */
1038 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1039 {
1040         nfs_increment_seqid(status, seqid);
1041 }
1042
1043 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1044 {
1045         struct nfs_seqid_counter *sequence = seqid->sequence;
1046         int status = 0;
1047
1048         spin_lock(&sequence->lock);
1049         seqid->task = task;
1050         if (list_empty(&seqid->list))
1051                 list_add_tail(&seqid->list, &sequence->list);
1052         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1053                 goto unlock;
1054         rpc_sleep_on(&sequence->wait, task, NULL);
1055         status = -EAGAIN;
1056 unlock:
1057         spin_unlock(&sequence->lock);
1058         return status;
1059 }
1060
1061 static int nfs4_run_state_manager(void *);
1062
1063 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1064 {
1065         smp_mb__before_clear_bit();
1066         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1067         smp_mb__after_clear_bit();
1068         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1069         rpc_wake_up(&clp->cl_rpcwaitq);
1070 }
1071
1072 /*
1073  * Schedule the nfs_client asynchronous state management routine
1074  */
1075 void nfs4_schedule_state_manager(struct nfs_client *clp)
1076 {
1077         struct task_struct *task;
1078         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1079
1080         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1081                 return;
1082         __module_get(THIS_MODULE);
1083         atomic_inc(&clp->cl_count);
1084
1085         /* The rcu_read_lock() is not strictly necessary, as the state
1086          * manager is the only thread that ever changes the rpc_xprt
1087          * after it's initialized.  At this point, we're single threaded. */
1088         rcu_read_lock();
1089         snprintf(buf, sizeof(buf), "%s-manager",
1090                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1091         rcu_read_unlock();
1092         task = kthread_run(nfs4_run_state_manager, clp, buf);
1093         if (IS_ERR(task)) {
1094                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1095                         __func__, PTR_ERR(task));
1096                 nfs4_clear_state_manager_bit(clp);
1097                 nfs_put_client(clp);
1098                 module_put(THIS_MODULE);
1099         }
1100 }
1101
1102 /*
1103  * Schedule a lease recovery attempt
1104  */
1105 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1106 {
1107         if (!clp)
1108                 return;
1109         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1110                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1111         nfs4_schedule_state_manager(clp);
1112 }
1113 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1114
1115 /*
1116  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1117  * @clp: client to process
1118  *
1119  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1120  * resend of the SETCLIENTID and hence re-establish the
1121  * callback channel. Then return all existing delegations.
1122  */
1123 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1124 {
1125         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1126         nfs_expire_all_delegations(clp);
1127 }
1128
1129 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1130 {
1131         nfs40_handle_cb_pathdown(clp);
1132         nfs4_schedule_state_manager(clp);
1133 }
1134
1135 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1136 {
1137
1138         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1139         /* Don't recover state that expired before the reboot */
1140         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1141                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1142                 return 0;
1143         }
1144         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1145         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1146         return 1;
1147 }
1148
1149 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1150 {
1151         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1152         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1153         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1154         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1155         return 1;
1156 }
1157
1158 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1159 {
1160         struct nfs_client *clp = server->nfs_client;
1161
1162         nfs4_state_mark_reclaim_nograce(clp, state);
1163         nfs4_schedule_state_manager(clp);
1164 }
1165 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1166
1167 void nfs_inode_find_state_and_recover(struct inode *inode,
1168                 const nfs4_stateid *stateid)
1169 {
1170         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1171         struct nfs_inode *nfsi = NFS_I(inode);
1172         struct nfs_open_context *ctx;
1173         struct nfs4_state *state;
1174         bool found = false;
1175
1176         spin_lock(&inode->i_lock);
1177         list_for_each_entry(ctx, &nfsi->open_files, list) {
1178                 state = ctx->state;
1179                 if (state == NULL)
1180                         continue;
1181                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1182                         continue;
1183                 if (!nfs4_stateid_match(&state->stateid, stateid))
1184                         continue;
1185                 nfs4_state_mark_reclaim_nograce(clp, state);
1186                 found = true;
1187         }
1188         spin_unlock(&inode->i_lock);
1189         if (found)
1190                 nfs4_schedule_state_manager(clp);
1191 }
1192
1193
1194 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1195 {
1196         struct inode *inode = state->inode;
1197         struct nfs_inode *nfsi = NFS_I(inode);
1198         struct file_lock *fl;
1199         int status = 0;
1200
1201         if (inode->i_flock == NULL)
1202                 return 0;
1203
1204         /* Guard against delegation returns and new lock/unlock calls */
1205         down_write(&nfsi->rwsem);
1206         /* Protect inode->i_flock using the BKL */
1207         lock_flocks();
1208         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1209                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1210                         continue;
1211                 if (nfs_file_open_context(fl->fl_file)->state != state)
1212                         continue;
1213                 unlock_flocks();
1214                 status = ops->recover_lock(state, fl);
1215                 switch (status) {
1216                         case 0:
1217                                 break;
1218                         case -ESTALE:
1219                         case -NFS4ERR_ADMIN_REVOKED:
1220                         case -NFS4ERR_STALE_STATEID:
1221                         case -NFS4ERR_BAD_STATEID:
1222                         case -NFS4ERR_EXPIRED:
1223                         case -NFS4ERR_NO_GRACE:
1224                         case -NFS4ERR_STALE_CLIENTID:
1225                         case -NFS4ERR_BADSESSION:
1226                         case -NFS4ERR_BADSLOT:
1227                         case -NFS4ERR_BAD_HIGH_SLOT:
1228                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1229                                 goto out;
1230                         default:
1231                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1232                                         "Zeroing state\n", __func__, status);
1233                         case -ENOMEM:
1234                         case -NFS4ERR_DENIED:
1235                         case -NFS4ERR_RECLAIM_BAD:
1236                         case -NFS4ERR_RECLAIM_CONFLICT:
1237                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1238                                 status = 0;
1239                 }
1240                 lock_flocks();
1241         }
1242         unlock_flocks();
1243 out:
1244         up_write(&nfsi->rwsem);
1245         return status;
1246 }
1247
1248 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1249 {
1250         struct nfs4_state *state;
1251         struct nfs4_lock_state *lock;
1252         int status = 0;
1253
1254         /* Note: we rely on the sp->so_states list being ordered
1255          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1256          * states first.
1257          * This is needed to ensure that the server won't give us any
1258          * read delegations that we have to return if, say, we are
1259          * recovering after a network partition or a reboot from a
1260          * server that doesn't support a grace period.
1261          */
1262 restart:
1263         spin_lock(&sp->so_lock);
1264         list_for_each_entry(state, &sp->so_states, open_states) {
1265                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1266                         continue;
1267                 if (state->state == 0)
1268                         continue;
1269                 atomic_inc(&state->count);
1270                 spin_unlock(&sp->so_lock);
1271                 status = ops->recover_open(sp, state);
1272                 if (status >= 0) {
1273                         status = nfs4_reclaim_locks(state, ops);
1274                         if (status >= 0) {
1275                                 spin_lock(&state->state_lock);
1276                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1277                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1278                                                 pr_warn_ratelimited("NFS: "
1279                                                         "%s: Lock reclaim "
1280                                                         "failed!\n", __func__);
1281                                 }
1282                                 spin_unlock(&state->state_lock);
1283                                 nfs4_put_open_state(state);
1284                                 goto restart;
1285                         }
1286                 }
1287                 switch (status) {
1288                         default:
1289                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1290                                         "Zeroing state\n", __func__, status);
1291                         case -ENOENT:
1292                         case -ENOMEM:
1293                         case -ESTALE:
1294                                 /*
1295                                  * Open state on this file cannot be recovered
1296                                  * All we can do is revert to using the zero stateid.
1297                                  */
1298                                 memset(&state->stateid, 0,
1299                                         sizeof(state->stateid));
1300                                 /* Mark the file as being 'closed' */
1301                                 state->state = 0;
1302                                 break;
1303                         case -EKEYEXPIRED:
1304                                 /*
1305                                  * User RPCSEC_GSS context has expired.
1306                                  * We cannot recover this stateid now, so
1307                                  * skip it and allow recovery thread to
1308                                  * proceed.
1309                                  */
1310                                 break;
1311                         case -NFS4ERR_ADMIN_REVOKED:
1312                         case -NFS4ERR_STALE_STATEID:
1313                         case -NFS4ERR_BAD_STATEID:
1314                         case -NFS4ERR_RECLAIM_BAD:
1315                         case -NFS4ERR_RECLAIM_CONFLICT:
1316                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1317                                 break;
1318                         case -NFS4ERR_EXPIRED:
1319                         case -NFS4ERR_NO_GRACE:
1320                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1321                         case -NFS4ERR_STALE_CLIENTID:
1322                         case -NFS4ERR_BADSESSION:
1323                         case -NFS4ERR_BADSLOT:
1324                         case -NFS4ERR_BAD_HIGH_SLOT:
1325                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1326                                 goto out_err;
1327                 }
1328                 nfs4_put_open_state(state);
1329                 goto restart;
1330         }
1331         spin_unlock(&sp->so_lock);
1332         return 0;
1333 out_err:
1334         nfs4_put_open_state(state);
1335         return status;
1336 }
1337
1338 static void nfs4_clear_open_state(struct nfs4_state *state)
1339 {
1340         struct nfs4_lock_state *lock;
1341
1342         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1343         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1344         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1345         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1346         spin_lock(&state->state_lock);
1347         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1348                 lock->ls_seqid.flags = 0;
1349                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1350         }
1351         spin_unlock(&state->state_lock);
1352 }
1353
1354 static void nfs4_reset_seqids(struct nfs_server *server,
1355         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1356 {
1357         struct nfs_client *clp = server->nfs_client;
1358         struct nfs4_state_owner *sp;
1359         struct rb_node *pos;
1360         struct nfs4_state *state;
1361
1362         spin_lock(&clp->cl_lock);
1363         for (pos = rb_first(&server->state_owners);
1364              pos != NULL;
1365              pos = rb_next(pos)) {
1366                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1367                 sp->so_seqid.flags = 0;
1368                 spin_lock(&sp->so_lock);
1369                 list_for_each_entry(state, &sp->so_states, open_states) {
1370                         if (mark_reclaim(clp, state))
1371                                 nfs4_clear_open_state(state);
1372                 }
1373                 spin_unlock(&sp->so_lock);
1374         }
1375         spin_unlock(&clp->cl_lock);
1376 }
1377
1378 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1379         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1380 {
1381         struct nfs_server *server;
1382
1383         rcu_read_lock();
1384         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1385                 nfs4_reset_seqids(server, mark_reclaim);
1386         rcu_read_unlock();
1387 }
1388
1389 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1390 {
1391         /* Mark all delegations for reclaim */
1392         nfs_delegation_mark_reclaim(clp);
1393         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1394 }
1395
1396 static void nfs4_reclaim_complete(struct nfs_client *clp,
1397                                  const struct nfs4_state_recovery_ops *ops)
1398 {
1399         /* Notify the server we're done reclaiming our state */
1400         if (ops->reclaim_complete)
1401                 (void)ops->reclaim_complete(clp);
1402 }
1403
1404 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1405 {
1406         struct nfs_client *clp = server->nfs_client;
1407         struct nfs4_state_owner *sp;
1408         struct rb_node *pos;
1409         struct nfs4_state *state;
1410
1411         spin_lock(&clp->cl_lock);
1412         for (pos = rb_first(&server->state_owners);
1413              pos != NULL;
1414              pos = rb_next(pos)) {
1415                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1416                 spin_lock(&sp->so_lock);
1417                 list_for_each_entry(state, &sp->so_states, open_states) {
1418                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1419                                                 &state->flags))
1420                                 continue;
1421                         nfs4_state_mark_reclaim_nograce(clp, state);
1422                 }
1423                 spin_unlock(&sp->so_lock);
1424         }
1425         spin_unlock(&clp->cl_lock);
1426 }
1427
1428 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1429 {
1430         struct nfs_server *server;
1431
1432         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1433                 return 0;
1434
1435         rcu_read_lock();
1436         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1437                 nfs4_clear_reclaim_server(server);
1438         rcu_read_unlock();
1439
1440         nfs_delegation_reap_unclaimed(clp);
1441         return 1;
1442 }
1443
1444 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1445 {
1446         if (!nfs4_state_clear_reclaim_reboot(clp))
1447                 return;
1448         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1449 }
1450
1451 static void nfs_delegation_clear_all(struct nfs_client *clp)
1452 {
1453         nfs_delegation_mark_reclaim(clp);
1454         nfs_delegation_reap_unclaimed(clp);
1455 }
1456
1457 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1458 {
1459         nfs_delegation_clear_all(clp);
1460         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1461 }
1462
1463 static void nfs4_warn_keyexpired(const char *s)
1464 {
1465         printk_ratelimited(KERN_WARNING "Error: state manager"
1466                         " encountered RPCSEC_GSS session"
1467                         " expired against NFSv4 server %s.\n",
1468                         s);
1469 }
1470
1471 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1472 {
1473         switch (error) {
1474                 case 0:
1475                         break;
1476                 case -NFS4ERR_CB_PATH_DOWN:
1477                         nfs40_handle_cb_pathdown(clp);
1478                         break;
1479                 case -NFS4ERR_NO_GRACE:
1480                         nfs4_state_end_reclaim_reboot(clp);
1481                         break;
1482                 case -NFS4ERR_STALE_CLIENTID:
1483                 case -NFS4ERR_LEASE_MOVED:
1484                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1485                         nfs4_state_clear_reclaim_reboot(clp);
1486                         nfs4_state_start_reclaim_reboot(clp);
1487                         break;
1488                 case -NFS4ERR_EXPIRED:
1489                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1490                         nfs4_state_start_reclaim_nograce(clp);
1491                         break;
1492                 case -NFS4ERR_BADSESSION:
1493                 case -NFS4ERR_BADSLOT:
1494                 case -NFS4ERR_BAD_HIGH_SLOT:
1495                 case -NFS4ERR_DEADSESSION:
1496                 case -NFS4ERR_SEQ_FALSE_RETRY:
1497                 case -NFS4ERR_SEQ_MISORDERED:
1498                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1499                         /* Zero session reset errors */
1500                         break;
1501                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1502                         set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1503                         break;
1504                 case -EKEYEXPIRED:
1505                         /* Nothing we can do */
1506                         nfs4_warn_keyexpired(clp->cl_hostname);
1507                         break;
1508                 default:
1509                         return error;
1510         }
1511         return 0;
1512 }
1513
1514 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1515 {
1516         struct nfs4_state_owner *sp;
1517         struct nfs_server *server;
1518         struct rb_node *pos;
1519         int status = 0;
1520
1521 restart:
1522         rcu_read_lock();
1523         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1524                 nfs4_purge_state_owners(server);
1525                 spin_lock(&clp->cl_lock);
1526                 for (pos = rb_first(&server->state_owners);
1527                      pos != NULL;
1528                      pos = rb_next(pos)) {
1529                         sp = rb_entry(pos,
1530                                 struct nfs4_state_owner, so_server_node);
1531                         if (!test_and_clear_bit(ops->owner_flag_bit,
1532                                                         &sp->so_flags))
1533                                 continue;
1534                         atomic_inc(&sp->so_count);
1535                         spin_unlock(&clp->cl_lock);
1536                         rcu_read_unlock();
1537
1538                         status = nfs4_reclaim_open_state(sp, ops);
1539                         if (status < 0) {
1540                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1541                                 nfs4_put_state_owner(sp);
1542                                 return nfs4_recovery_handle_error(clp, status);
1543                         }
1544
1545                         nfs4_put_state_owner(sp);
1546                         goto restart;
1547                 }
1548                 spin_unlock(&clp->cl_lock);
1549         }
1550         rcu_read_unlock();
1551         return status;
1552 }
1553
1554 static int nfs4_check_lease(struct nfs_client *clp)
1555 {
1556         struct rpc_cred *cred;
1557         const struct nfs4_state_maintenance_ops *ops =
1558                 clp->cl_mvops->state_renewal_ops;
1559         int status;
1560
1561         /* Is the client already known to have an expired lease? */
1562         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1563                 return 0;
1564         spin_lock(&clp->cl_lock);
1565         cred = ops->get_state_renewal_cred_locked(clp);
1566         spin_unlock(&clp->cl_lock);
1567         if (cred == NULL) {
1568                 cred = nfs4_get_setclientid_cred(clp);
1569                 status = -ENOKEY;
1570                 if (cred == NULL)
1571                         goto out;
1572         }
1573         status = ops->renew_lease(clp, cred);
1574         put_rpccred(cred);
1575 out:
1576         return nfs4_recovery_handle_error(clp, status);
1577 }
1578
1579 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1580  * on EXCHANGE_ID for v4.1
1581  */
1582 static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
1583 {
1584         switch (status) {
1585         case -NFS4ERR_SEQ_MISORDERED:
1586                 if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
1587                         return -ESERVERFAULT;
1588                 /* Lease confirmation error: retry after purging the lease */
1589                 ssleep(1);
1590         case -NFS4ERR_CLID_INUSE:
1591         case -NFS4ERR_STALE_CLIENTID:
1592                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1593                 break;
1594         case -EACCES:
1595                 if (clp->cl_machine_cred == NULL)
1596                         return -EACCES;
1597                 /* Handle case where the user hasn't set up machine creds */
1598                 nfs4_clear_machine_cred(clp);
1599         case -NFS4ERR_DELAY:
1600         case -ETIMEDOUT:
1601         case -EAGAIN:
1602                 ssleep(1);
1603                 break;
1604
1605         case -NFS4ERR_MINOR_VERS_MISMATCH:
1606                 if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1607                         nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
1608                 return -EPROTONOSUPPORT;
1609         case -EKEYEXPIRED:
1610                 nfs4_warn_keyexpired(clp->cl_hostname);
1611         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1612                                  * in nfs4_exchange_id */
1613         default:
1614                 return status;
1615         }
1616         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1617         return 0;
1618 }
1619
1620 static int nfs4_reclaim_lease(struct nfs_client *clp)
1621 {
1622         struct rpc_cred *cred;
1623         const struct nfs4_state_recovery_ops *ops =
1624                 clp->cl_mvops->reboot_recovery_ops;
1625         int status;
1626
1627         cred = ops->get_clid_cred(clp);
1628         if (cred == NULL)
1629                 return -ENOENT;
1630         status = ops->establish_clid(clp, cred);
1631         put_rpccred(cred);
1632         if (status != 0)
1633                 return nfs4_handle_reclaim_lease_error(clp, status);
1634         return 0;
1635 }
1636
1637 #ifdef CONFIG_NFS_V4_1
1638 void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
1639 {
1640         struct nfs_client *clp = session->clp;
1641
1642         switch (err) {
1643         default:
1644                 set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1645                 break;
1646         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1647                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1648         }
1649         nfs4_schedule_lease_recovery(clp);
1650 }
1651 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1652
1653 void nfs41_handle_recall_slot(struct nfs_client *clp)
1654 {
1655         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1656         nfs4_schedule_state_manager(clp);
1657 }
1658
1659 static void nfs4_reset_all_state(struct nfs_client *clp)
1660 {
1661         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1662                 set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1663                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1664                 nfs4_state_start_reclaim_nograce(clp);
1665                 nfs4_schedule_state_manager(clp);
1666         }
1667 }
1668
1669 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1670 {
1671         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1672                 nfs4_state_start_reclaim_reboot(clp);
1673                 nfs4_schedule_state_manager(clp);
1674         }
1675 }
1676
1677 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1678 {
1679         nfs4_reset_all_state(clp);
1680 }
1681
1682 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1683 {
1684         /* This will need to handle layouts too */
1685         nfs_expire_all_delegations(clp);
1686 }
1687
1688 static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
1689 {
1690         nfs_expire_all_delegations(clp);
1691         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1692                 nfs4_schedule_state_manager(clp);
1693 }
1694
1695 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1696 {
1697         if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
1698                 &clp->cl_state) == 0)
1699                 nfs4_schedule_state_manager(clp);
1700 }
1701
1702 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1703 {
1704         if (!flags)
1705                 return;
1706
1707         dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
1708                 __func__, clp->cl_hostname, clp->cl_clientid, flags);
1709
1710         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1711                 nfs41_handle_server_reboot(clp);
1712         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1713                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1714                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1715                             SEQ4_STATUS_LEASE_MOVED))
1716                 nfs41_handle_state_revoked(clp);
1717         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1718                 nfs41_handle_recallable_state_revoked(clp);
1719         if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
1720                 nfs41_handle_backchannel_fault(clp);
1721         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1722                                 SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1723                 nfs41_handle_cb_path_down(clp);
1724 }
1725
1726 static int nfs4_reset_session(struct nfs_client *clp)
1727 {
1728         struct rpc_cred *cred;
1729         int status;
1730
1731         nfs4_begin_drain_session(clp);
1732         cred = nfs4_get_exchange_id_cred(clp);
1733         status = nfs4_proc_destroy_session(clp->cl_session, cred);
1734         if (status && status != -NFS4ERR_BADSESSION &&
1735             status != -NFS4ERR_DEADSESSION) {
1736                 status = nfs4_recovery_handle_error(clp, status);
1737                 goto out;
1738         }
1739
1740         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1741         status = nfs4_proc_create_session(clp, cred);
1742         if (status) {
1743                 status = nfs4_handle_reclaim_lease_error(clp, status);
1744                 goto out;
1745         }
1746         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1747         /* create_session negotiated new slot table */
1748         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1749         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1750
1751          /* Let the state manager reestablish state */
1752         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1753                 nfs41_setup_state_renewal(clp);
1754 out:
1755         if (cred)
1756                 put_rpccred(cred);
1757         return status;
1758 }
1759
1760 static int nfs4_recall_slot(struct nfs_client *clp)
1761 {
1762         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1763         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1764         struct nfs4_slot *new, *old;
1765         int i;
1766
1767         nfs4_begin_drain_session(clp);
1768         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1769                       GFP_NOFS);
1770         if (!new)
1771                 return -ENOMEM;
1772
1773         spin_lock(&fc_tbl->slot_tbl_lock);
1774         for (i = 0; i < fc_tbl->target_max_slots; i++)
1775                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1776         old = fc_tbl->slots;
1777         fc_tbl->slots = new;
1778         fc_tbl->max_slots = fc_tbl->target_max_slots;
1779         fc_tbl->target_max_slots = 0;
1780         fc_attrs->max_reqs = fc_tbl->max_slots;
1781         spin_unlock(&fc_tbl->slot_tbl_lock);
1782
1783         kfree(old);
1784         nfs4_end_drain_session(clp);
1785         return 0;
1786 }
1787
1788 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
1789 {
1790         struct rpc_cred *cred;
1791         int ret;
1792
1793         nfs4_begin_drain_session(clp);
1794         cred = nfs4_get_exchange_id_cred(clp);
1795         ret = nfs4_proc_bind_conn_to_session(clp, cred);
1796         if (cred)
1797                 put_rpccred(cred);
1798         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1799         switch (ret) {
1800         case 0:
1801                 break;
1802         case -NFS4ERR_DELAY:
1803                 ssleep(1);
1804                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1805                 break;
1806         default:
1807                 return nfs4_recovery_handle_error(clp, ret);
1808         }
1809         return 0;
1810 }
1811 #else /* CONFIG_NFS_V4_1 */
1812 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1813 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1814 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1815
1816 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
1817 {
1818         return 0;
1819 }
1820 #endif /* CONFIG_NFS_V4_1 */
1821
1822 static void nfs4_state_manager(struct nfs_client *clp)
1823 {
1824         int status = 0;
1825
1826         /* Ensure exclusive access to NFSv4 state */
1827         do {
1828                 if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
1829                         status = nfs4_reclaim_lease(clp);
1830                         if (status < 0)
1831                                 goto out_error;
1832                         clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1833                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1834                 }
1835
1836                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1837                         /* We're going to have to re-establish a clientid */
1838                         status = nfs4_reclaim_lease(clp);
1839                         if (status < 0)
1840                                 goto out_error;
1841                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1842                                 continue;
1843                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1844
1845                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1846                                                &clp->cl_state))
1847                                 nfs4_state_start_reclaim_nograce(clp);
1848                         else
1849                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1850                                         &clp->cl_state);
1851
1852                         pnfs_destroy_all_layouts(clp);
1853                 }
1854
1855                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1856                         status = nfs4_check_lease(clp);
1857                         if (status < 0)
1858                                 goto out_error;
1859                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1860                                 continue;
1861                 }
1862
1863                 /* Initialize or reset the session */
1864                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1865                    && nfs4_has_session(clp)) {
1866                         status = nfs4_reset_session(clp);
1867                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1868                                 continue;
1869                         if (status < 0)
1870                                 goto out_error;
1871                 }
1872
1873                 /* Send BIND_CONN_TO_SESSION */
1874                 if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
1875                                 &clp->cl_state) && nfs4_has_session(clp)) {
1876                         status = nfs4_bind_conn_to_session(clp);
1877                         if (status < 0)
1878                                 goto out_error;
1879                         continue;
1880                 }
1881
1882                 /* First recover reboot state... */
1883                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1884                         status = nfs4_do_reclaim(clp,
1885                                 clp->cl_mvops->reboot_recovery_ops);
1886                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1887                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1888                                 continue;
1889                         nfs4_state_end_reclaim_reboot(clp);
1890                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1891                                 continue;
1892                         if (status < 0)
1893                                 goto out_error;
1894                 }
1895
1896                 /* Now recover expired state... */
1897                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1898                         status = nfs4_do_reclaim(clp,
1899                                 clp->cl_mvops->nograce_recovery_ops);
1900                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1901                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1902                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1903                                 continue;
1904                         if (status < 0)
1905                                 goto out_error;
1906                 }
1907
1908                 nfs4_end_drain_session(clp);
1909                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1910                         nfs_client_return_marked_delegations(clp);
1911                         continue;
1912                 }
1913                 /* Recall session slots */
1914                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1915                    && nfs4_has_session(clp)) {
1916                         status = nfs4_recall_slot(clp);
1917                         if (status < 0)
1918                                 goto out_error;
1919                         continue;
1920                 }
1921
1922
1923                 nfs4_clear_state_manager_bit(clp);
1924                 /* Did we race with an attempt to give us more work? */
1925                 if (clp->cl_state == 0)
1926                         break;
1927                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1928                         break;
1929         } while (atomic_read(&clp->cl_count) > 1);
1930         return;
1931 out_error:
1932         pr_warn_ratelimited("NFS: state manager failed on NFSv4 server %s"
1933                         " with error %d\n", clp->cl_hostname, -status);
1934         nfs4_end_drain_session(clp);
1935         nfs4_clear_state_manager_bit(clp);
1936 }
1937
1938 static int nfs4_run_state_manager(void *ptr)
1939 {
1940         struct nfs_client *clp = ptr;
1941
1942         allow_signal(SIGKILL);
1943         nfs4_state_manager(clp);
1944         nfs_put_client(clp);
1945         module_put_and_exit(0);
1946         return 0;
1947 }
1948
1949 /*
1950  * Local variables:
1951  *  c-basic-offset: 8
1952  * End:
1953  */