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 "nfs4_fs.h"
  55 #include "callback.h"
  56 #include "delegation.h"
  57 #include "internal.h"
  58 #include "pnfs.h"
  59
  60 #define OPENOWNER_POOL_SIZE     8
  61
  62 const nfs4_stateid zero_stateid;
  63
  64 static LIST_HEAD(nfs4_clientid_list);
  65
  66 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  67 {
  68         struct nfs4_setclientid_res clid = {
  69                 .clientid = clp->cl_clientid,
  70                 .confirm = clp->cl_confirm,
  71         };
  72         unsigned short port;
  73         int status;
  74
  75         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
  76                 goto do_confirm;
  77         port = nfs_callback_tcpport;
  78         if (clp->cl_addr.ss_family == AF_INET6)
  79                 port = nfs_callback_tcpport6;
  80
  81         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
  82         if (status != 0)
  83                 goto out;
  84         clp->cl_clientid = clid.clientid;
  85         clp->cl_confirm = clid.confirm;
  86         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  87 do_confirm:
  88         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
  89         if (status != 0)
  90                 goto out;
  91         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  92         nfs4_schedule_state_renewal(clp);
  93 out:
  94         return status;
  95 }
  96
  97 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
  98 {
  99         struct rpc_cred *cred = NULL;
 100
 101         if (clp->cl_machine_cred != NULL)
 102                 cred = get_rpccred(clp->cl_machine_cred);
 103         return cred;
 104 }
 105
 106 static void nfs4_clear_machine_cred(struct nfs_client *clp)
 107 {
 108         struct rpc_cred *cred;
 109
 110         spin_lock(&clp->cl_lock);
 111         cred = clp->cl_machine_cred;
 112         clp->cl_machine_cred = NULL;
 113         spin_unlock(&clp->cl_lock);
 114         if (cred != NULL)
 115                 put_rpccred(cred);
 116 }
 117
 118 static struct rpc_cred *
 119 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 120 {
 121         struct rpc_cred *cred = NULL;
 122         struct nfs4_state_owner *sp;
 123         struct rb_node *pos;
 124
 125         for (pos = rb_first(&server->state_owners);
 126              pos != NULL;
 127              pos = rb_next(pos)) {
 128                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 129                 if (list_empty(&sp->so_states))
 130                         continue;
 131                 cred = get_rpccred(sp->so_cred);
 132                 break;
 133         }
 134         return cred;
 135 }
 136
 137 /**
 138  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
 139  * @clp: client state handle
 140  *
 141  * Returns an rpc_cred with reference count bumped, or NULL.
 142  * Caller must hold clp->cl_lock.
 143  */
 144 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 145 {
 146         struct rpc_cred *cred = NULL;
 147         struct nfs_server *server;
 148
 149         rcu_read_lock();
 150         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 151                 cred = nfs4_get_renew_cred_server_locked(server);
 152                 if (cred != NULL)
 153                         break;
 154         }
 155         rcu_read_unlock();
 156         return cred;
 157 }
 158
 159 #if defined(CONFIG_NFS_V4_1)
 160
 161 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 162 {
 163         int status;
 164         struct nfs_fsinfo fsinfo;
 165
 166         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
 167                 nfs4_schedule_state_renewal(clp);
 168                 return 0;
 169         }
 170
 171         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 172         if (status == 0) {
 173                 /* Update lease time and schedule renewal */
 174                 spin_lock(&clp->cl_lock);
 175                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 176                 clp->cl_last_renewal = jiffies;
 177                 spin_unlock(&clp->cl_lock);
 178
 179                 nfs4_schedule_state_renewal(clp);
 180         }
 181
 182         return status;
 183 }
 184
 185 /*
 186  * Back channel returns NFS4ERR_DELAY for new requests when
 187  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
 188  * is ended.
 189  */
 190 static void nfs4_end_drain_session(struct nfs_client *clp)
 191 {
 192         struct nfs4_session *ses = clp->cl_session;
 193         int max_slots;
 194
 195         if (ses == NULL)
 196                 return;
 197         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
 198                 spin_lock(&ses->fc_slot_table.slot_tbl_lock);
 199                 max_slots = ses->fc_slot_table.max_slots;
 200                 while (max_slots--) {
 201                         struct rpc_task *task;
 202
 203                         task = rpc_wake_up_next(&ses->fc_slot_table.
 204                                                 slot_tbl_waitq);
 205                         if (!task)
 206                                 break;
 207                         rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED);
 208                 }
 209                 spin_unlock(&ses->fc_slot_table.slot_tbl_lock);
 210         }
 211 }
 212
 213 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
 214 {
 215         spin_lock(&tbl->slot_tbl_lock);
 216         if (tbl->highest_used_slotid != -1) {
 217                 INIT_COMPLETION(tbl->complete);
 218                 spin_unlock(&tbl->slot_tbl_lock);
 219                 return wait_for_completion_interruptible(&tbl->complete);
 220         }
 221         spin_unlock(&tbl->slot_tbl_lock);
 222         return 0;
 223 }
 224
 225 static int nfs4_begin_drain_session(struct nfs_client *clp)
 226 {
 227         struct nfs4_session *ses = clp->cl_session;
 228         int ret = 0;
 229
 230         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
 231         /* back channel */
 232         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
 233         if (ret)
 234                 return ret;
 235         /* fore channel */
 236         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
 237 }
 238
 239 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 240 {
 241         int status;
 242
 243         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 244                 goto do_confirm;
 245         nfs4_begin_drain_session(clp);
 246         status = nfs4_proc_exchange_id(clp, cred);
 247         if (status != 0)
 248                 goto out;
 249         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 250 do_confirm:
 251         status = nfs4_proc_create_session(clp);
 252         if (status != 0)
 253                 goto out;
 254         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 255         nfs41_setup_state_renewal(clp);
 256         nfs_mark_client_ready(clp, NFS_CS_READY);
 257 out:
 258         return status;
 259 }
 260
 261 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 262 {
 263         struct rpc_cred *cred;
 264
 265         spin_lock(&clp->cl_lock);
 266         cred = nfs4_get_machine_cred_locked(clp);
 267         spin_unlock(&clp->cl_lock);
 268         return cred;
 269 }
 270
 271 #endif /* CONFIG_NFS_V4_1 */
 272
 273 static struct rpc_cred *
 274 nfs4_get_setclientid_cred_server(struct nfs_server *server)
 275 {
 276         struct nfs_client *clp = server->nfs_client;
 277         struct rpc_cred *cred = NULL;
 278         struct nfs4_state_owner *sp;
 279         struct rb_node *pos;
 280
 281         spin_lock(&clp->cl_lock);
 282         pos = rb_first(&server->state_owners);
 283         if (pos != NULL) {
 284                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 285                 cred = get_rpccred(sp->so_cred);
 286         }
 287         spin_unlock(&clp->cl_lock);
 288         return cred;
 289 }
 290
 291 /**
 292  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
 293  * @clp: client state handle
 294  *
 295  * Returns an rpc_cred with reference count bumped, or NULL.
 296  */
 297 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 298 {
 299         struct nfs_server *server;
 300         struct rpc_cred *cred;
 301
 302         spin_lock(&clp->cl_lock);
 303         cred = nfs4_get_machine_cred_locked(clp);
 304         spin_unlock(&clp->cl_lock);
 305         if (cred != NULL)
 306                 goto out;
 307
 308         rcu_read_lock();
 309         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 310                 cred = nfs4_get_setclientid_cred_server(server);
 311                 if (cred != NULL)
 312                         break;
 313         }
 314         rcu_read_unlock();
 315
 316 out:
 317         return cred;
 318 }
 319
 320 static void nfs_alloc_unique_id_locked(struct rb_root *root,
 321                                        struct nfs_unique_id *new,
 322                                        __u64 minval, int maxbits)
 323 {
 324         struct rb_node **p, *parent;
 325         struct nfs_unique_id *pos;
 326         __u64 mask = ~0ULL;
 327
 328         if (maxbits < 64)
 329                 mask = (1ULL << maxbits) - 1ULL;
 330
 331         /* Ensure distribution is more or less flat */
 332         get_random_bytes(&new->id, sizeof(new->id));
 333         new->id &= mask;
 334         if (new->id < minval)
 335                 new->id += minval;
 336 retry:
 337         p = &root->rb_node;
 338         parent = NULL;
 339
 340         while (*p != NULL) {
 341                 parent = *p;
 342                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 343
 344                 if (new->id < pos->id)
 345                         p = &(*p)->rb_left;
 346                 else if (new->id > pos->id)
 347                         p = &(*p)->rb_right;
 348                 else
 349                         goto id_exists;
 350         }
 351         rb_link_node(&new->rb_node, parent, p);
 352         rb_insert_color(&new->rb_node, root);
 353         return;
 354 id_exists:
 355         for (;;) {
 356                 new->id++;
 357                 if (new->id < minval || (new->id & mask) != new->id) {
 358                         new->id = minval;
 359                         break;
 360                 }
 361                 parent = rb_next(parent);
 362                 if (parent == NULL)
 363                         break;
 364                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 365                 if (new->id < pos->id)
 366                         break;
 367         }
 368         goto retry;
 369 }
 370
 371 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
 372 {
 373         rb_erase(&id->rb_node, root);
 374 }
 375
 376 static struct nfs4_state_owner *
 377 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
 378 {
 379         struct rb_node **p = &server->state_owners.rb_node,
 380                        *parent = NULL;
 381         struct nfs4_state_owner *sp;
 382
 383         while (*p != NULL) {
 384                 parent = *p;
 385                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 386
 387                 if (cred < sp->so_cred)
 388                         p = &parent->rb_left;
 389                 else if (cred > sp->so_cred)
 390                         p = &parent->rb_right;
 391                 else {
 392                         if (!list_empty(&sp->so_lru))
 393                                 list_del_init(&sp->so_lru);
 394                         atomic_inc(&sp->so_count);
 395                         return sp;
 396                 }
 397         }
 398         return NULL;
 399 }
 400
 401 static struct nfs4_state_owner *
 402 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 403 {
 404         struct nfs_server *server = new->so_server;
 405         struct rb_node **p = &server->state_owners.rb_node,
 406                        *parent = NULL;
 407         struct nfs4_state_owner *sp;
 408
 409         while (*p != NULL) {
 410                 parent = *p;
 411                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 412
 413                 if (new->so_cred < sp->so_cred)
 414                         p = &parent->rb_left;
 415                 else if (new->so_cred > sp->so_cred)
 416                         p = &parent->rb_right;
 417                 else {
 418                         if (!list_empty(&sp->so_lru))
 419                                 list_del_init(&sp->so_lru);
 420                         atomic_inc(&sp->so_count);
 421                         return sp;
 422                 }
 423         }
 424         nfs_alloc_unique_id_locked(&server->openowner_id,
 425                                         &new->so_owner_id, 1, 64);
 426         rb_link_node(&new->so_server_node, parent, p);
 427         rb_insert_color(&new->so_server_node, &server->state_owners);
 428         return new;
 429 }
 430
 431 static void
 432 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 433 {
 434         struct nfs_server *server = sp->so_server;
 435
 436         if (!RB_EMPTY_NODE(&sp->so_server_node))
 437                 rb_erase(&sp->so_server_node, &server->state_owners);
 438         nfs_free_unique_id(&server->openowner_id, &sp->so_owner_id);
 439 }
 440
 441 /*
 442  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 443  * create a new state_owner.
 444  *
 445  */
 446 static struct nfs4_state_owner *
 447 nfs4_alloc_state_owner(struct nfs_server *server,
 448                 struct rpc_cred *cred,
 449                 gfp_t gfp_flags)
 450 {
 451         struct nfs4_state_owner *sp;
 452
 453         sp = kzalloc(sizeof(*sp), gfp_flags);
 454         if (!sp)
 455                 return NULL;
 456         sp->so_server = server;
 457         sp->so_cred = get_rpccred(cred);
 458         spin_lock_init(&sp->so_lock);
 459         INIT_LIST_HEAD(&sp->so_states);
 460         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 461         sp->so_seqid.sequence = &sp->so_sequence;
 462         spin_lock_init(&sp->so_sequence.lock);
 463         INIT_LIST_HEAD(&sp->so_sequence.list);
 464         atomic_set(&sp->so_count, 1);
 465         INIT_LIST_HEAD(&sp->so_lru);
 466         return sp;
 467 }
 468
 469 static void
 470 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 471 {
 472         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
 473                 struct nfs_server *server = sp->so_server;
 474                 struct nfs_client *clp = server->nfs_client;
 475
 476                 spin_lock(&clp->cl_lock);
 477                 rb_erase(&sp->so_server_node, &server->state_owners);
 478                 RB_CLEAR_NODE(&sp->so_server_node);
 479                 spin_unlock(&clp->cl_lock);
 480         }
 481 }
 482
 483 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 484 {
 485         rpc_destroy_wait_queue(&sp->so_sequence.wait);
 486         put_rpccred(sp->so_cred);
 487         kfree(sp);
 488 }
 489
 490 static void nfs4_gc_state_owners(struct nfs_server *server)
 491 {
 492         struct nfs_client *clp = server->nfs_client;
 493         struct nfs4_state_owner *sp, *tmp;
 494         unsigned long time_min, time_max;
 495         LIST_HEAD(doomed);
 496
 497         spin_lock(&clp->cl_lock);
 498         time_max = jiffies;
 499         time_min = (long)time_max - (long)clp->cl_lease_time;
 500         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 501                 /* NB: LRU is sorted so that oldest is at the head */
 502                 if (time_in_range(sp->so_expires, time_min, time_max))
 503                         break;
 504                 list_move(&sp->so_lru, &doomed);
 505                 nfs4_remove_state_owner_locked(sp);
 506         }
 507         spin_unlock(&clp->cl_lock);
 508
 509         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 510                 list_del(&sp->so_lru);
 511                 nfs4_free_state_owner(sp);
 512         }
 513 }
 514
 515 /**
 516  * nfs4_get_state_owner - Look up a state owner given a credential
 517  * @server: nfs_server to search
 518  * @cred: RPC credential to match
 519  *
 520  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 521  */
 522 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 523                                               struct rpc_cred *cred,
 524                                               gfp_t gfp_flags)
 525 {
 526         struct nfs_client *clp = server->nfs_client;
 527         struct nfs4_state_owner *sp, *new;
 528
 529         spin_lock(&clp->cl_lock);
 530         sp = nfs4_find_state_owner_locked(server, cred);
 531         spin_unlock(&clp->cl_lock);
 532         if (sp != NULL)
 533                 goto out;
 534         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 535         if (new == NULL)
 536                 goto out;
 537         sp = nfs4_insert_state_owner_locked(new);
 538         spin_unlock(&clp->cl_lock);
 539         if (sp != new)
 540                 nfs4_free_state_owner(new);
 541 out:
 542         nfs4_gc_state_owners(server);
 543         return sp;
 544 }
 545
 546 /**
 547  * nfs4_put_state_owner - Release a nfs4_state_owner
 548  * @sp: state owner data to release
 549  */
 550 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 551 {
 552         struct nfs_server *server = sp->so_server;
 553         struct nfs_client *clp = server->nfs_client;
 554
 555         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 556                 return;
 557
 558         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
 559                 sp->so_expires = jiffies;
 560                 list_add_tail(&sp->so_lru, &server->state_owners_lru);
 561                 spin_unlock(&clp->cl_lock);
 562         } else {
 563                 nfs4_remove_state_owner_locked(sp);
 564                 spin_unlock(&clp->cl_lock);
 565                 nfs4_free_state_owner(sp);
 566         }
 567 }
 568
 569 /**
 570  * nfs4_purge_state_owners - Release all cached state owners
 571  * @server: nfs_server with cached state owners to release
 572  *
 573  * Called at umount time.  Remaining state owners will be on
 574  * the LRU with ref count of zero.
 575  */
 576 void nfs4_purge_state_owners(struct nfs_server *server)
 577 {
 578         struct nfs_client *clp = server->nfs_client;
 579         struct nfs4_state_owner *sp, *tmp;
 580         LIST_HEAD(doomed);
 581
 582         spin_lock(&clp->cl_lock);
 583         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 584                 list_move(&sp->so_lru, &doomed);
 585                 nfs4_remove_state_owner_locked(sp);
 586         }
 587         spin_unlock(&clp->cl_lock);
 588
 589         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 590                 list_del(&sp->so_lru);
 591                 nfs4_free_state_owner(sp);
 592         }
 593 }
 594
 595 static struct nfs4_state *
 596 nfs4_alloc_open_state(void)
 597 {
 598         struct nfs4_state *state;
 599
 600         state = kzalloc(sizeof(*state), GFP_NOFS);
 601         if (!state)
 602                 return NULL;
 603         atomic_set(&state->count, 1);
 604         INIT_LIST_HEAD(&state->lock_states);
 605         spin_lock_init(&state->state_lock);
 606         seqlock_init(&state->seqlock);
 607         return state;
 608 }
 609
 610 void
 611 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 612 {
 613         if (state->state == fmode)
 614                 return;
 615         /* NB! List reordering - see the reclaim code for why.  */
 616         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 617                 if (fmode & FMODE_WRITE)
 618                         list_move(&state->open_states, &state->owner->so_states);
 619                 else
 620                         list_move_tail(&state->open_states, &state->owner->so_states);
 621         }
 622         state->state = fmode;
 623 }
 624
 625 static struct nfs4_state *
 626 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 627 {
 628         struct nfs_inode *nfsi = NFS_I(inode);
 629         struct nfs4_state *state;
 630
 631         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 632                 if (state->owner != owner)
 633                         continue;
 634                 if (atomic_inc_not_zero(&state->count))
 635                         return state;
 636         }
 637         return NULL;
 638 }
 639
 640 static void
 641 nfs4_free_open_state(struct nfs4_state *state)
 642 {
 643         kfree(state);
 644 }
 645
 646 struct nfs4_state *
 647 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 648 {
 649         struct nfs4_state *state, *new;
 650         struct nfs_inode *nfsi = NFS_I(inode);
 651
 652         spin_lock(&inode->i_lock);
 653         state = __nfs4_find_state_byowner(inode, owner);
 654         spin_unlock(&inode->i_lock);
 655         if (state)
 656                 goto out;
 657         new = nfs4_alloc_open_state();
 658         spin_lock(&owner->so_lock);
 659         spin_lock(&inode->i_lock);
 660         state = __nfs4_find_state_byowner(inode, owner);
 661         if (state == NULL && new != NULL) {
 662                 state = new;
 663                 state->owner = owner;
 664                 atomic_inc(&owner->so_count);
 665                 list_add(&state->inode_states, &nfsi->open_states);
 666                 ihold(inode);
 667                 state->inode = inode;
 668                 spin_unlock(&inode->i_lock);
 669                 /* Note: The reclaim code dictates that we add stateless
 670                  * and read-only stateids to the end of the list */
 671                 list_add_tail(&state->open_states, &owner->so_states);
 672                 spin_unlock(&owner->so_lock);
 673         } else {
 674                 spin_unlock(&inode->i_lock);
 675                 spin_unlock(&owner->so_lock);
 676                 if (new)
 677                         nfs4_free_open_state(new);
 678         }
 679 out:
 680         return state;
 681 }
 682
 683 void nfs4_put_open_state(struct nfs4_state *state)
 684 {
 685         struct inode *inode = state->inode;
 686         struct nfs4_state_owner *owner = state->owner;
 687
 688         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 689                 return;
 690         spin_lock(&inode->i_lock);
 691         list_del(&state->inode_states);
 692         list_del(&state->open_states);
 693         spin_unlock(&inode->i_lock);
 694         spin_unlock(&owner->so_lock);
 695         iput(inode);
 696         nfs4_free_open_state(state);
 697         nfs4_put_state_owner(owner);
 698 }
 699
 700 /*
 701  * Close the current file.
 702  */
 703 static void __nfs4_close(struct nfs4_state *state,
 704                 fmode_t fmode, gfp_t gfp_mask, int wait)
 705 {
 706         struct nfs4_state_owner *owner = state->owner;
 707         int call_close = 0;
 708         fmode_t newstate;
 709
 710         atomic_inc(&owner->so_count);
 711         /* Protect against nfs4_find_state() */
 712         spin_lock(&owner->so_lock);
 713         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 714                 case FMODE_READ:
 715                         state->n_rdonly--;
 716                         break;
 717                 case FMODE_WRITE:
 718                         state->n_wronly--;
 719                         break;
 720                 case FMODE_READ|FMODE_WRITE:
 721                         state->n_rdwr--;
 722         }
 723         newstate = FMODE_READ|FMODE_WRITE;
 724         if (state->n_rdwr == 0) {
 725                 if (state->n_rdonly == 0) {
 726                         newstate &= ~FMODE_READ;
 727                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 728                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 729                 }
 730                 if (state->n_wronly == 0) {
 731                         newstate &= ~FMODE_WRITE;
 732                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 733                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 734                 }
 735                 if (newstate == 0)
 736                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 737         }
 738         nfs4_state_set_mode_locked(state, newstate);
 739         spin_unlock(&owner->so_lock);
 740
 741         if (!call_close) {
 742                 nfs4_put_open_state(state);
 743                 nfs4_put_state_owner(owner);
 744         } else {
 745                 bool roc = pnfs_roc(state->inode);
 746
 747                 nfs4_do_close(state, gfp_mask, wait, roc);
 748         }
 749 }
 750
 751 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 752 {
 753         __nfs4_close(state, fmode, GFP_NOFS, 0);
 754 }
 755
 756 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 757 {
 758         __nfs4_close(state, fmode, GFP_KERNEL, 1);
 759 }
 760
 761 /*
 762  * Search the state->lock_states for an existing lock_owner
 763  * that is compatible with current->files
 764  */
 765 static struct nfs4_lock_state *
 766 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 767 {
 768         struct nfs4_lock_state *pos;
 769         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 770                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
 771                         continue;
 772                 switch (pos->ls_owner.lo_type) {
 773                 case NFS4_POSIX_LOCK_TYPE:
 774                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
 775                                 continue;
 776                         break;
 777                 case NFS4_FLOCK_LOCK_TYPE:
 778                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
 779                                 continue;
 780                 }
 781                 atomic_inc(&pos->ls_count);
 782                 return pos;
 783         }
 784         return NULL;
 785 }
 786
 787 /*
 788  * Return a compatible lock_state. If no initialized lock_state structure
 789  * exists, return an uninitialized one.
 790  *
 791  */
 792 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)
 793 {
 794         struct nfs4_lock_state *lsp;
 795         struct nfs_server *server = state->owner->so_server;
 796         struct nfs_client *clp = server->nfs_client;
 797
 798         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 799         if (lsp == NULL)
 800                 return NULL;
 801         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 802         spin_lock_init(&lsp->ls_sequence.lock);
 803         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 804         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 805         atomic_set(&lsp->ls_count, 1);
 806         lsp->ls_state = state;
 807         lsp->ls_owner.lo_type = type;
 808         switch (lsp->ls_owner.lo_type) {
 809         case NFS4_FLOCK_LOCK_TYPE:
 810                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
 811                 break;
 812         case NFS4_POSIX_LOCK_TYPE:
 813                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
 814                 break;
 815         default:
 816                 kfree(lsp);
 817                 return NULL;
 818         }
 819         spin_lock(&clp->cl_lock);
 820         nfs_alloc_unique_id_locked(&server->lockowner_id, &lsp->ls_id, 1, 64);
 821         spin_unlock(&clp->cl_lock);
 822         INIT_LIST_HEAD(&lsp->ls_locks);
 823         return lsp;
 824 }
 825
 826 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 827 {
 828         struct nfs_server *server = lsp->ls_state->owner->so_server;
 829         struct nfs_client *clp = server->nfs_client;
 830
 831         spin_lock(&clp->cl_lock);
 832         nfs_free_unique_id(&server->lockowner_id, &lsp->ls_id);
 833         spin_unlock(&clp->cl_lock);
 834         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 835         kfree(lsp);
 836 }
 837
 838 /*
 839  * Return a compatible lock_state. If no initialized lock_state structure
 840  * exists, return an uninitialized one.
 841  *
 842  */
 843 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
 844 {
 845         struct nfs4_lock_state *lsp, *new = NULL;
 846
 847         for(;;) {
 848                 spin_lock(&state->state_lock);
 849                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
 850                 if (lsp != NULL)
 851                         break;
 852                 if (new != NULL) {
 853                         list_add(&new->ls_locks, &state->lock_states);
 854                         set_bit(LK_STATE_IN_USE, &state->flags);
 855                         lsp = new;
 856                         new = NULL;
 857                         break;
 858                 }
 859                 spin_unlock(&state->state_lock);
 860                 new = nfs4_alloc_lock_state(state, owner, pid, type);
 861                 if (new == NULL)
 862                         return NULL;
 863         }
 864         spin_unlock(&state->state_lock);
 865         if (new != NULL)
 866                 nfs4_free_lock_state(new);
 867         return lsp;
 868 }
 869
 870 /*
 871  * Release reference to lock_state, and free it if we see that
 872  * it is no longer in use
 873  */
 874 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 875 {
 876         struct nfs4_state *state;
 877
 878         if (lsp == NULL)
 879                 return;
 880         state = lsp->ls_state;
 881         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 882                 return;
 883         list_del(&lsp->ls_locks);
 884         if (list_empty(&state->lock_states))
 885                 clear_bit(LK_STATE_IN_USE, &state->flags);
 886         spin_unlock(&state->state_lock);
 887         if (lsp->ls_flags & NFS_LOCK_INITIALIZED)
 888                 nfs4_release_lockowner(lsp);
 889         nfs4_free_lock_state(lsp);
 890 }
 891
 892 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 893 {
 894         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 895
 896         dst->fl_u.nfs4_fl.owner = lsp;
 897         atomic_inc(&lsp->ls_count);
 898 }
 899
 900 static void nfs4_fl_release_lock(struct file_lock *fl)
 901 {
 902         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 903 }
 904
 905 static const struct file_lock_operations nfs4_fl_lock_ops = {
 906         .fl_copy_lock = nfs4_fl_copy_lock,
 907         .fl_release_private = nfs4_fl_release_lock,
 908 };
 909
 910 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 911 {
 912         struct nfs4_lock_state *lsp;
 913
 914         if (fl->fl_ops != NULL)
 915                 return 0;
 916         if (fl->fl_flags & FL_POSIX)
 917                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
 918         else if (fl->fl_flags & FL_FLOCK)
 919                 lsp = nfs4_get_lock_state(state, 0, fl->fl_pid, NFS4_FLOCK_LOCK_TYPE);
 920         else
 921                 return -EINVAL;
 922         if (lsp == NULL)
 923                 return -ENOMEM;
 924         fl->fl_u.nfs4_fl.owner = lsp;
 925         fl->fl_ops = &nfs4_fl_lock_ops;
 926         return 0;
 927 }
 928
 929 /*
 930  * Byte-range lock aware utility to initialize the stateid of read/write
 931  * requests.
 932  */
 933 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid)
 934 {
 935         struct nfs4_lock_state *lsp;
 936         int seq;
 937
 938         do {
 939                 seq = read_seqbegin(&state->seqlock);
 940                 memcpy(dst, &state->stateid, sizeof(*dst));
 941         } while (read_seqretry(&state->seqlock, seq));
 942         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 943                 return;
 944
 945         spin_lock(&state->state_lock);
 946         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
 947         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 948                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 949         spin_unlock(&state->state_lock);
 950         nfs4_put_lock_state(lsp);
 951 }
 952
 953 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
 954 {
 955         struct nfs_seqid *new;
 956
 957         new = kmalloc(sizeof(*new), gfp_mask);
 958         if (new != NULL) {
 959                 new->sequence = counter;
 960                 INIT_LIST_HEAD(&new->list);
 961         }
 962         return new;
 963 }
 964
 965 void nfs_release_seqid(struct nfs_seqid *seqid)
 966 {
 967         if (!list_empty(&seqid->list)) {
 968                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 969
 970                 spin_lock(&sequence->lock);
 971                 list_del_init(&seqid->list);
 972                 spin_unlock(&sequence->lock);
 973                 rpc_wake_up(&sequence->wait);
 974         }
 975 }
 976
 977 void nfs_free_seqid(struct nfs_seqid *seqid)
 978 {
 979         nfs_release_seqid(seqid);
 980         kfree(seqid);
 981 }
 982
 983 /*
 984  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 985  * failed with a seqid incrementing error -
 986  * see comments nfs_fs.h:seqid_mutating_error()
 987  */
 988 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 989 {
 990         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 991         switch (status) {
 992                 case 0:
 993                         break;
 994                 case -NFS4ERR_BAD_SEQID:
 995                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
 996                                 return;
 997                         printk(KERN_WARNING "NFS: v4 server returned a bad"
 998                                         " sequence-id error on an"
 999                                         " unconfirmed sequence %p!\n",
1000                                         seqid->sequence);
1001                 case -NFS4ERR_STALE_CLIENTID:
1002                 case -NFS4ERR_STALE_STATEID:
1003                 case -NFS4ERR_BAD_STATEID:
1004                 case -NFS4ERR_BADXDR:
1005                 case -NFS4ERR_RESOURCE:
1006                 case -NFS4ERR_NOFILEHANDLE:
1007                         /* Non-seqid mutating errors */
1008                         return;
1009         };
1010         /*
1011          * Note: no locking needed as we are guaranteed to be first
1012          * on the sequence list
1013          */
1014         seqid->sequence->counter++;
1015 }
1016
1017 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1018 {
1019         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1020                                         struct nfs4_state_owner, so_seqid);
1021         struct nfs_server *server = sp->so_server;
1022
1023         if (status == -NFS4ERR_BAD_SEQID)
1024                 nfs4_drop_state_owner(sp);
1025         if (!nfs4_has_session(server->nfs_client))
1026                 nfs_increment_seqid(status, seqid);
1027 }
1028
1029 /*
1030  * Increment the seqid if the LOCK/LOCKU succeeded, or
1031  * failed with a seqid incrementing error -
1032  * see comments nfs_fs.h:seqid_mutating_error()
1033  */
1034 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1035 {
1036         nfs_increment_seqid(status, seqid);
1037 }
1038
1039 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1040 {
1041         struct rpc_sequence *sequence = seqid->sequence->sequence;
1042         int status = 0;
1043
1044         spin_lock(&sequence->lock);
1045         if (list_empty(&seqid->list))
1046                 list_add_tail(&seqid->list, &sequence->list);
1047         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1048                 goto unlock;
1049         rpc_sleep_on(&sequence->wait, task, NULL);
1050         status = -EAGAIN;
1051 unlock:
1052         spin_unlock(&sequence->lock);
1053         return status;
1054 }
1055
1056 static int nfs4_run_state_manager(void *);
1057
1058 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1059 {
1060         smp_mb__before_clear_bit();
1061         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1062         smp_mb__after_clear_bit();
1063         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1064         rpc_wake_up(&clp->cl_rpcwaitq);
1065 }
1066
1067 /*
1068  * Schedule the nfs_client asynchronous state management routine
1069  */
1070 void nfs4_schedule_state_manager(struct nfs_client *clp)
1071 {
1072         struct task_struct *task;
1073
1074         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1075                 return;
1076         __module_get(THIS_MODULE);
1077         atomic_inc(&clp->cl_count);
1078         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
1079                                 rpc_peeraddr2str(clp->cl_rpcclient,
1080                                                         RPC_DISPLAY_ADDR));
1081         if (!IS_ERR(task))
1082                 return;
1083         nfs4_clear_state_manager_bit(clp);
1084         nfs_put_client(clp);
1085         module_put(THIS_MODULE);
1086 }
1087
1088 /*
1089  * Schedule a lease recovery attempt
1090  */
1091 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1092 {
1093         if (!clp)
1094                 return;
1095         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1096                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1097         nfs4_schedule_state_manager(clp);
1098 }
1099
1100 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1101 {
1102         nfs_handle_cb_pathdown(clp);
1103         nfs4_schedule_state_manager(clp);
1104 }
1105
1106 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1107 {
1108
1109         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1110         /* Don't recover state that expired before the reboot */
1111         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1112                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1113                 return 0;
1114         }
1115         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1116         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1117         return 1;
1118 }
1119
1120 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1121 {
1122         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1123         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1124         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1125         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1126         return 1;
1127 }
1128
1129 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1130 {
1131         struct nfs_client *clp = server->nfs_client;
1132
1133         nfs4_state_mark_reclaim_nograce(clp, state);
1134         nfs4_schedule_state_manager(clp);
1135 }
1136
1137 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1138 {
1139         struct inode *inode = state->inode;
1140         struct nfs_inode *nfsi = NFS_I(inode);
1141         struct file_lock *fl;
1142         int status = 0;
1143
1144         if (inode->i_flock == NULL)
1145                 return 0;
1146
1147         /* Guard against delegation returns and new lock/unlock calls */
1148         down_write(&nfsi->rwsem);
1149         /* Protect inode->i_flock using the BKL */
1150         lock_flocks();
1151         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1152                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1153                         continue;
1154                 if (nfs_file_open_context(fl->fl_file)->state != state)
1155                         continue;
1156                 unlock_flocks();
1157                 status = ops->recover_lock(state, fl);
1158                 switch (status) {
1159                         case 0:
1160                                 break;
1161                         case -ESTALE:
1162                         case -NFS4ERR_ADMIN_REVOKED:
1163                         case -NFS4ERR_STALE_STATEID:
1164                         case -NFS4ERR_BAD_STATEID:
1165                         case -NFS4ERR_EXPIRED:
1166                         case -NFS4ERR_NO_GRACE:
1167                         case -NFS4ERR_STALE_CLIENTID:
1168                         case -NFS4ERR_BADSESSION:
1169                         case -NFS4ERR_BADSLOT:
1170                         case -NFS4ERR_BAD_HIGH_SLOT:
1171                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1172                                 goto out;
1173                         default:
1174                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1175                                                 __func__, status);
1176                         case -ENOMEM:
1177                         case -NFS4ERR_DENIED:
1178                         case -NFS4ERR_RECLAIM_BAD:
1179                         case -NFS4ERR_RECLAIM_CONFLICT:
1180                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1181                                 status = 0;
1182                 }
1183                 lock_flocks();
1184         }
1185         unlock_flocks();
1186 out:
1187         up_write(&nfsi->rwsem);
1188         return status;
1189 }
1190
1191 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1192 {
1193         struct nfs4_state *state;
1194         struct nfs4_lock_state *lock;
1195         int status = 0;
1196
1197         /* Note: we rely on the sp->so_states list being ordered
1198          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1199          * states first.
1200          * This is needed to ensure that the server won't give us any
1201          * read delegations that we have to return if, say, we are
1202          * recovering after a network partition or a reboot from a
1203          * server that doesn't support a grace period.
1204          */
1205 restart:
1206         spin_lock(&sp->so_lock);
1207         list_for_each_entry(state, &sp->so_states, open_states) {
1208                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1209                         continue;
1210                 if (state->state == 0)
1211                         continue;
1212                 atomic_inc(&state->count);
1213                 spin_unlock(&sp->so_lock);
1214                 status = ops->recover_open(sp, state);
1215                 if (status >= 0) {
1216                         status = nfs4_reclaim_locks(state, ops);
1217                         if (status >= 0) {
1218                                 spin_lock(&state->state_lock);
1219                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1220                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1221                                                 printk("%s: Lock reclaim failed!\n",
1222                                                         __func__);
1223                                 }
1224                                 spin_unlock(&state->state_lock);
1225                                 nfs4_put_open_state(state);
1226                                 goto restart;
1227                         }
1228                 }
1229                 switch (status) {
1230                         default:
1231                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1232                                                 __func__, status);
1233                         case -ENOENT:
1234                         case -ENOMEM:
1235                         case -ESTALE:
1236                                 /*
1237                                  * Open state on this file cannot be recovered
1238                                  * All we can do is revert to using the zero stateid.
1239                                  */
1240                                 memset(state->stateid.data, 0,
1241                                         sizeof(state->stateid.data));
1242                                 /* Mark the file as being 'closed' */
1243                                 state->state = 0;
1244                                 break;
1245                         case -EKEYEXPIRED:
1246                                 /*
1247                                  * User RPCSEC_GSS context has expired.
1248                                  * We cannot recover this stateid now, so
1249                                  * skip it and allow recovery thread to
1250                                  * proceed.
1251                                  */
1252                                 break;
1253                         case -NFS4ERR_ADMIN_REVOKED:
1254                         case -NFS4ERR_STALE_STATEID:
1255                         case -NFS4ERR_BAD_STATEID:
1256                         case -NFS4ERR_RECLAIM_BAD:
1257                         case -NFS4ERR_RECLAIM_CONFLICT:
1258                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1259                                 break;
1260                         case -NFS4ERR_EXPIRED:
1261                         case -NFS4ERR_NO_GRACE:
1262                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1263                         case -NFS4ERR_STALE_CLIENTID:
1264                         case -NFS4ERR_BADSESSION:
1265                         case -NFS4ERR_BADSLOT:
1266                         case -NFS4ERR_BAD_HIGH_SLOT:
1267                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1268                                 goto out_err;
1269                 }
1270                 nfs4_put_open_state(state);
1271                 goto restart;
1272         }
1273         spin_unlock(&sp->so_lock);
1274         return 0;
1275 out_err:
1276         nfs4_put_open_state(state);
1277         return status;
1278 }
1279
1280 static void nfs4_clear_open_state(struct nfs4_state *state)
1281 {
1282         struct nfs4_lock_state *lock;
1283
1284         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1285         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1286         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1287         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1288         spin_lock(&state->state_lock);
1289         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1290                 lock->ls_seqid.flags = 0;
1291                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1292         }
1293         spin_unlock(&state->state_lock);
1294 }
1295
1296 static void nfs4_reset_seqids(struct nfs_server *server,
1297         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1298 {
1299         struct nfs_client *clp = server->nfs_client;
1300         struct nfs4_state_owner *sp;
1301         struct rb_node *pos;
1302         struct nfs4_state *state;
1303
1304         spin_lock(&clp->cl_lock);
1305         for (pos = rb_first(&server->state_owners);
1306              pos != NULL;
1307              pos = rb_next(pos)) {
1308                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1309                 sp->so_seqid.flags = 0;
1310                 spin_lock(&sp->so_lock);
1311                 list_for_each_entry(state, &sp->so_states, open_states) {
1312                         if (mark_reclaim(clp, state))
1313                                 nfs4_clear_open_state(state);
1314                 }
1315                 spin_unlock(&sp->so_lock);
1316         }
1317         spin_unlock(&clp->cl_lock);
1318 }
1319
1320 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1321         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1322 {
1323         struct nfs_server *server;
1324
1325         rcu_read_lock();
1326         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1327                 nfs4_reset_seqids(server, mark_reclaim);
1328         rcu_read_unlock();
1329 }
1330
1331 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1332 {
1333         /* Mark all delegations for reclaim */
1334         nfs_delegation_mark_reclaim(clp);
1335         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1336 }
1337
1338 static void nfs4_reclaim_complete(struct nfs_client *clp,
1339                                  const struct nfs4_state_recovery_ops *ops)
1340 {
1341         /* Notify the server we're done reclaiming our state */
1342         if (ops->reclaim_complete)
1343                 (void)ops->reclaim_complete(clp);
1344 }
1345
1346 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1347 {
1348         struct nfs_client *clp = server->nfs_client;
1349         struct nfs4_state_owner *sp;
1350         struct rb_node *pos;
1351         struct nfs4_state *state;
1352
1353         spin_lock(&clp->cl_lock);
1354         for (pos = rb_first(&server->state_owners);
1355              pos != NULL;
1356              pos = rb_next(pos)) {
1357                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1358                 spin_lock(&sp->so_lock);
1359                 list_for_each_entry(state, &sp->so_states, open_states) {
1360                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1361                                                 &state->flags))
1362                                 continue;
1363                         nfs4_state_mark_reclaim_nograce(clp, state);
1364                 }
1365                 spin_unlock(&sp->so_lock);
1366         }
1367         spin_unlock(&clp->cl_lock);
1368 }
1369
1370 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1371 {
1372         struct nfs_server *server;
1373
1374         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1375                 return 0;
1376
1377         rcu_read_lock();
1378         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1379                 nfs4_clear_reclaim_server(server);
1380         rcu_read_unlock();
1381
1382         nfs_delegation_reap_unclaimed(clp);
1383         return 1;
1384 }
1385
1386 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1387 {
1388         if (!nfs4_state_clear_reclaim_reboot(clp))
1389                 return;
1390         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1391 }
1392
1393 static void nfs_delegation_clear_all(struct nfs_client *clp)
1394 {
1395         nfs_delegation_mark_reclaim(clp);
1396         nfs_delegation_reap_unclaimed(clp);
1397 }
1398
1399 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1400 {
1401         nfs_delegation_clear_all(clp);
1402         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1403 }
1404
1405 static void nfs4_warn_keyexpired(const char *s)
1406 {
1407         printk_ratelimited(KERN_WARNING "Error: state manager"
1408                         " encountered RPCSEC_GSS session"
1409                         " expired against NFSv4 server %s.\n",
1410                         s);
1411 }
1412
1413 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1414 {
1415         switch (error) {
1416                 case 0:
1417                         break;
1418                 case -NFS4ERR_CB_PATH_DOWN:
1419                         nfs_handle_cb_pathdown(clp);
1420                         break;
1421                 case -NFS4ERR_NO_GRACE:
1422                         nfs4_state_end_reclaim_reboot(clp);
1423                         break;
1424                 case -NFS4ERR_STALE_CLIENTID:
1425                 case -NFS4ERR_LEASE_MOVED:
1426                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1427                         nfs4_state_clear_reclaim_reboot(clp);
1428                         nfs4_state_start_reclaim_reboot(clp);
1429                         break;
1430                 case -NFS4ERR_EXPIRED:
1431                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1432                         nfs4_state_start_reclaim_nograce(clp);
1433                         break;
1434                 case -NFS4ERR_BADSESSION:
1435                 case -NFS4ERR_BADSLOT:
1436                 case -NFS4ERR_BAD_HIGH_SLOT:
1437                 case -NFS4ERR_DEADSESSION:
1438                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1439                 case -NFS4ERR_SEQ_FALSE_RETRY:
1440                 case -NFS4ERR_SEQ_MISORDERED:
1441                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1442                         /* Zero session reset errors */
1443                         break;
1444                 case -EKEYEXPIRED:
1445                         /* Nothing we can do */
1446                         nfs4_warn_keyexpired(clp->cl_hostname);
1447                         break;
1448                 default:
1449                         return error;
1450         }
1451         return 0;
1452 }
1453
1454 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1455 {
1456         struct nfs4_state_owner *sp;
1457         struct nfs_server *server;
1458         struct rb_node *pos;
1459         int status = 0;
1460
1461 restart:
1462         rcu_read_lock();
1463         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1464                 nfs4_purge_state_owners(server);
1465                 spin_lock(&clp->cl_lock);
1466                 for (pos = rb_first(&server->state_owners);
1467                      pos != NULL;
1468                      pos = rb_next(pos)) {
1469                         sp = rb_entry(pos,
1470                                 struct nfs4_state_owner, so_server_node);
1471                         if (!test_and_clear_bit(ops->owner_flag_bit,
1472                                                         &sp->so_flags))
1473                                 continue;
1474                         atomic_inc(&sp->so_count);
1475                         spin_unlock(&clp->cl_lock);
1476                         rcu_read_unlock();
1477
1478                         status = nfs4_reclaim_open_state(sp, ops);
1479                         if (status < 0) {
1480                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1481                                 nfs4_put_state_owner(sp);
1482                                 return nfs4_recovery_handle_error(clp, status);
1483                         }
1484
1485                         nfs4_put_state_owner(sp);
1486                         goto restart;
1487                 }
1488                 spin_unlock(&clp->cl_lock);
1489         }
1490         rcu_read_unlock();
1491         return status;
1492 }
1493
1494 static int nfs4_check_lease(struct nfs_client *clp)
1495 {
1496         struct rpc_cred *cred;
1497         const struct nfs4_state_maintenance_ops *ops =
1498                 clp->cl_mvops->state_renewal_ops;
1499         int status;
1500
1501         /* Is the client already known to have an expired lease? */
1502         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1503                 return 0;
1504         spin_lock(&clp->cl_lock);
1505         cred = ops->get_state_renewal_cred_locked(clp);
1506         spin_unlock(&clp->cl_lock);
1507         if (cred == NULL) {
1508                 cred = nfs4_get_setclientid_cred(clp);
1509                 status = -ENOKEY;
1510                 if (cred == NULL)
1511                         goto out;
1512         }
1513         status = ops->renew_lease(clp, cred);
1514         put_rpccred(cred);
1515 out:
1516         return nfs4_recovery_handle_error(clp, status);
1517 }
1518
1519 static int nfs4_reclaim_lease(struct nfs_client *clp)
1520 {
1521         struct rpc_cred *cred;
1522         const struct nfs4_state_recovery_ops *ops =
1523                 clp->cl_mvops->reboot_recovery_ops;
1524         int status = -ENOENT;
1525
1526         cred = ops->get_clid_cred(clp);
1527         if (cred != NULL) {
1528                 status = ops->establish_clid(clp, cred);
1529                 put_rpccred(cred);
1530                 /* Handle case where the user hasn't set up machine creds */
1531                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1532                         nfs4_clear_machine_cred(clp);
1533                         status = -EAGAIN;
1534                 }
1535                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1536                         status = -EPROTONOSUPPORT;
1537         }
1538         return status;
1539 }
1540
1541 #ifdef CONFIG_NFS_V4_1
1542 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1543 {
1544         struct nfs_client *clp = session->clp;
1545
1546         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1547         nfs4_schedule_lease_recovery(clp);
1548 }
1549 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1550
1551 void nfs41_handle_recall_slot(struct nfs_client *clp)
1552 {
1553         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1554         nfs4_schedule_state_manager(clp);
1555 }
1556
1557 static void nfs4_reset_all_state(struct nfs_client *clp)
1558 {
1559         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1560                 clp->cl_boot_time = CURRENT_TIME;
1561                 nfs4_state_start_reclaim_nograce(clp);
1562                 nfs4_schedule_state_manager(clp);
1563         }
1564 }
1565
1566 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1567 {
1568         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1569                 nfs4_state_start_reclaim_reboot(clp);
1570                 nfs4_schedule_state_manager(clp);
1571         }
1572 }
1573
1574 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1575 {
1576         /* Temporary */
1577         nfs4_reset_all_state(clp);
1578 }
1579
1580 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1581 {
1582         /* This will need to handle layouts too */
1583         nfs_expire_all_delegations(clp);
1584 }
1585
1586 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1587 {
1588         nfs_expire_all_delegations(clp);
1589         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1590                 nfs4_schedule_state_manager(clp);
1591 }
1592
1593 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1594 {
1595         if (!flags)
1596                 return;
1597         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1598                 nfs41_handle_server_reboot(clp);
1599         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1600                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1601                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1602                             SEQ4_STATUS_LEASE_MOVED))
1603                 nfs41_handle_state_revoked(clp);
1604         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1605                 nfs41_handle_recallable_state_revoked(clp);
1606         if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1607                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1608                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1609                 nfs41_handle_cb_path_down(clp);
1610 }
1611
1612 static int nfs4_reset_session(struct nfs_client *clp)
1613 {
1614         int status;
1615
1616         nfs4_begin_drain_session(clp);
1617         status = nfs4_proc_destroy_session(clp->cl_session);
1618         if (status && status != -NFS4ERR_BADSESSION &&
1619             status != -NFS4ERR_DEADSESSION) {
1620                 status = nfs4_recovery_handle_error(clp, status);
1621                 goto out;
1622         }
1623
1624         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1625         status = nfs4_proc_create_session(clp);
1626         if (status) {
1627                 status = nfs4_recovery_handle_error(clp, status);
1628                 goto out;
1629         }
1630         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1631         /* create_session negotiated new slot table */
1632         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1633
1634          /* Let the state manager reestablish state */
1635         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1636                 nfs41_setup_state_renewal(clp);
1637 out:
1638         return status;
1639 }
1640
1641 static int nfs4_recall_slot(struct nfs_client *clp)
1642 {
1643         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1644         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1645         struct nfs4_slot *new, *old;
1646         int i;
1647
1648         nfs4_begin_drain_session(clp);
1649         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1650                       GFP_NOFS);
1651         if (!new)
1652                 return -ENOMEM;
1653
1654         spin_lock(&fc_tbl->slot_tbl_lock);
1655         for (i = 0; i < fc_tbl->target_max_slots; i++)
1656                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1657         old = fc_tbl->slots;
1658         fc_tbl->slots = new;
1659         fc_tbl->max_slots = fc_tbl->target_max_slots;
1660         fc_tbl->target_max_slots = 0;
1661         fc_attrs->max_reqs = fc_tbl->max_slots;
1662         spin_unlock(&fc_tbl->slot_tbl_lock);
1663
1664         kfree(old);
1665         nfs4_end_drain_session(clp);
1666         return 0;
1667 }
1668
1669 #else /* CONFIG_NFS_V4_1 */
1670 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1671 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1672 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1673 #endif /* CONFIG_NFS_V4_1 */
1674
1675 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1676  * on EXCHANGE_ID for v4.1
1677  */
1678 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1679 {
1680         switch (status) {
1681         case -NFS4ERR_CLID_INUSE:
1682         case -NFS4ERR_STALE_CLIENTID:
1683                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1684                 break;
1685         case -NFS4ERR_DELAY:
1686         case -ETIMEDOUT:
1687         case -EAGAIN:
1688                 ssleep(1);
1689                 break;
1690
1691         case -EKEYEXPIRED:
1692                 nfs4_warn_keyexpired(clp->cl_hostname);
1693         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1694                                  * in nfs4_exchange_id */
1695         default:
1696                 return;
1697         }
1698         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1699 }
1700
1701 static void nfs4_state_manager(struct nfs_client *clp)
1702 {
1703         int status = 0;
1704
1705         /* Ensure exclusive access to NFSv4 state */
1706         do {
1707                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1708                         /* We're going to have to re-establish a clientid */
1709                         status = nfs4_reclaim_lease(clp);
1710                         if (status) {
1711                                 nfs4_set_lease_expired(clp, status);
1712                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1713                                                         &clp->cl_state))
1714                                         continue;
1715                                 if (clp->cl_cons_state ==
1716                                                         NFS_CS_SESSION_INITING)
1717                                         nfs_mark_client_ready(clp, status);
1718                                 goto out_error;
1719                         }
1720                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1721
1722                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1723                                                &clp->cl_state))
1724                                 nfs4_state_start_reclaim_nograce(clp);
1725                         else
1726                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1727                                         &clp->cl_state);
1728
1729                         pnfs_destroy_all_layouts(clp);
1730                 }
1731
1732                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1733                         status = nfs4_check_lease(clp);
1734                         if (status < 0)
1735                                 goto out_error;
1736                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1737                                 continue;
1738                 }
1739
1740                 /* Initialize or reset the session */
1741                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1742                    && nfs4_has_session(clp)) {
1743                         status = nfs4_reset_session(clp);
1744                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1745                                 continue;
1746                         if (status < 0)
1747                                 goto out_error;
1748                 }
1749
1750                 /* First recover reboot state... */
1751                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1752                         status = nfs4_do_reclaim(clp,
1753                                 clp->cl_mvops->reboot_recovery_ops);
1754                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1755                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1756                                 continue;
1757                         nfs4_state_end_reclaim_reboot(clp);
1758                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1759                                 continue;
1760                         if (status < 0)
1761                                 goto out_error;
1762                 }
1763
1764                 /* Now recover expired state... */
1765                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1766                         status = nfs4_do_reclaim(clp,
1767                                 clp->cl_mvops->nograce_recovery_ops);
1768                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1769                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1770                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1771                                 continue;
1772                         if (status < 0)
1773                                 goto out_error;
1774                 }
1775
1776                 nfs4_end_drain_session(clp);
1777                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1778                         nfs_client_return_marked_delegations(clp);
1779                         continue;
1780                 }
1781                 /* Recall session slots */
1782                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1783                    && nfs4_has_session(clp)) {
1784                         status = nfs4_recall_slot(clp);
1785                         if (status < 0)
1786                                 goto out_error;
1787                         continue;
1788                 }
1789
1790
1791                 nfs4_clear_state_manager_bit(clp);
1792                 /* Did we race with an attempt to give us more work? */
1793                 if (clp->cl_state == 0)
1794                         break;
1795                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1796                         break;
1797         } while (atomic_read(&clp->cl_count) > 1);
1798         return;
1799 out_error:
1800         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1801                         " with error %d\n", clp->cl_hostname, -status);
1802         nfs4_end_drain_session(clp);
1803         nfs4_clear_state_manager_bit(clp);
1804 }
1805
1806 static int nfs4_run_state_manager(void *ptr)
1807 {
1808         struct nfs_client *clp = ptr;
1809
1810         allow_signal(SIGKILL);
1811         nfs4_state_manager(clp);
1812         nfs_put_client(clp);
1813         module_put_and_exit(0);
1814         return 0;
1815 }
1816
1817 /*
1818  * Local variables:
1819  *  c-basic-offset: 8
1820  * End:
1821  */