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         /* Use machine credentials if available */
 150         cred = nfs4_get_machine_cred_locked(clp);
 151         if (cred != NULL)
 152                 goto out;
 153
 154         rcu_read_lock();
 155         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 156                 cred = nfs4_get_renew_cred_server_locked(server);
 157                 if (cred != NULL)
 158                         break;
 159         }
 160         rcu_read_unlock();
 161
 162 out:
 163         return cred;
 164 }
 165
 166 #if defined(CONFIG_NFS_V4_1)
 167
 168 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 169 {
 170         int status;
 171         struct nfs_fsinfo fsinfo;
 172
 173         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
 174                 nfs4_schedule_state_renewal(clp);
 175                 return 0;
 176         }
 177
 178         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 179         if (status == 0) {
 180                 /* Update lease time and schedule renewal */
 181                 spin_lock(&clp->cl_lock);
 182                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 183                 clp->cl_last_renewal = jiffies;
 184                 spin_unlock(&clp->cl_lock);
 185
 186                 nfs4_schedule_state_renewal(clp);
 187         }
 188
 189         return status;
 190 }
 191
 192 /*
 193  * Back channel returns NFS4ERR_DELAY for new requests when
 194  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
 195  * is ended.
 196  */
 197 static void nfs4_end_drain_session(struct nfs_client *clp)
 198 {
 199         struct nfs4_session *ses = clp->cl_session;
 200         struct nfs4_slot_table *tbl;
 201         int max_slots;
 202
 203         if (ses == NULL)
 204                 return;
 205         tbl = &ses->fc_slot_table;
 206         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
 207                 spin_lock(&tbl->slot_tbl_lock);
 208                 max_slots = tbl->max_slots;
 209                 while (max_slots--) {
 210                         if (rpc_wake_up_first(&tbl->slot_tbl_waitq,
 211                                                 nfs4_set_task_privileged,
 212                                                 NULL) == NULL)
 213                                 break;
 214                 }
 215                 spin_unlock(&tbl->slot_tbl_lock);
 216         }
 217 }
 218
 219 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
 220 {
 221         spin_lock(&tbl->slot_tbl_lock);
 222         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
 223                 INIT_COMPLETION(tbl->complete);
 224                 spin_unlock(&tbl->slot_tbl_lock);
 225                 return wait_for_completion_interruptible(&tbl->complete);
 226         }
 227         spin_unlock(&tbl->slot_tbl_lock);
 228         return 0;
 229 }
 230
 231 static int nfs4_begin_drain_session(struct nfs_client *clp)
 232 {
 233         struct nfs4_session *ses = clp->cl_session;
 234         int ret = 0;
 235
 236         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
 237         /* back channel */
 238         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
 239         if (ret)
 240                 return ret;
 241         /* fore channel */
 242         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
 243 }
 244
 245 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 246 {
 247         int status;
 248
 249         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 250                 goto do_confirm;
 251         nfs4_begin_drain_session(clp);
 252         status = nfs4_proc_exchange_id(clp, cred);
 253         if (status != 0)
 254                 goto out;
 255         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 256 do_confirm:
 257         status = nfs4_proc_create_session(clp);
 258         if (status != 0)
 259                 goto out;
 260         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 261         nfs41_setup_state_renewal(clp);
 262         nfs_mark_client_ready(clp, NFS_CS_READY);
 263 out:
 264         return status;
 265 }
 266
 267 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 268 {
 269         struct rpc_cred *cred;
 270
 271         spin_lock(&clp->cl_lock);
 272         cred = nfs4_get_machine_cred_locked(clp);
 273         spin_unlock(&clp->cl_lock);
 274         return cred;
 275 }
 276
 277 #endif /* CONFIG_NFS_V4_1 */
 278
 279 static struct rpc_cred *
 280 nfs4_get_setclientid_cred_server(struct nfs_server *server)
 281 {
 282         struct nfs_client *clp = server->nfs_client;
 283         struct rpc_cred *cred = NULL;
 284         struct nfs4_state_owner *sp;
 285         struct rb_node *pos;
 286
 287         spin_lock(&clp->cl_lock);
 288         pos = rb_first(&server->state_owners);
 289         if (pos != NULL) {
 290                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 291                 cred = get_rpccred(sp->so_cred);
 292         }
 293         spin_unlock(&clp->cl_lock);
 294         return cred;
 295 }
 296
 297 /**
 298  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
 299  * @clp: client state handle
 300  *
 301  * Returns an rpc_cred with reference count bumped, or NULL.
 302  */
 303 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 304 {
 305         struct nfs_server *server;
 306         struct rpc_cred *cred;
 307
 308         spin_lock(&clp->cl_lock);
 309         cred = nfs4_get_machine_cred_locked(clp);
 310         spin_unlock(&clp->cl_lock);
 311         if (cred != NULL)
 312                 goto out;
 313
 314         rcu_read_lock();
 315         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 316                 cred = nfs4_get_setclientid_cred_server(server);
 317                 if (cred != NULL)
 318                         break;
 319         }
 320         rcu_read_unlock();
 321
 322 out:
 323         return cred;
 324 }
 325
 326 static struct nfs4_state_owner *
 327 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
 328 {
 329         struct rb_node **p = &server->state_owners.rb_node,
 330                        *parent = NULL;
 331         struct nfs4_state_owner *sp;
 332
 333         while (*p != NULL) {
 334                 parent = *p;
 335                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 336
 337                 if (cred < sp->so_cred)
 338                         p = &parent->rb_left;
 339                 else if (cred > sp->so_cred)
 340                         p = &parent->rb_right;
 341                 else {
 342                         if (!list_empty(&sp->so_lru))
 343                                 list_del_init(&sp->so_lru);
 344                         atomic_inc(&sp->so_count);
 345                         return sp;
 346                 }
 347         }
 348         return NULL;
 349 }
 350
 351 static struct nfs4_state_owner *
 352 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 353 {
 354         struct nfs_server *server = new->so_server;
 355         struct rb_node **p = &server->state_owners.rb_node,
 356                        *parent = NULL;
 357         struct nfs4_state_owner *sp;
 358         int err;
 359
 360         while (*p != NULL) {
 361                 parent = *p;
 362                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 363
 364                 if (new->so_cred < sp->so_cred)
 365                         p = &parent->rb_left;
 366                 else if (new->so_cred > sp->so_cred)
 367                         p = &parent->rb_right;
 368                 else {
 369                         if (!list_empty(&sp->so_lru))
 370                                 list_del_init(&sp->so_lru);
 371                         atomic_inc(&sp->so_count);
 372                         return sp;
 373                 }
 374         }
 375         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
 376         if (err)
 377                 return ERR_PTR(err);
 378         rb_link_node(&new->so_server_node, parent, p);
 379         rb_insert_color(&new->so_server_node, &server->state_owners);
 380         return new;
 381 }
 382
 383 static void
 384 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 385 {
 386         struct nfs_server *server = sp->so_server;
 387
 388         if (!RB_EMPTY_NODE(&sp->so_server_node))
 389                 rb_erase(&sp->so_server_node, &server->state_owners);
 390         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
 391 }
 392
 393 static void
 394 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
 395 {
 396         sc->create_time = ktime_get();
 397         sc->flags = 0;
 398         sc->counter = 0;
 399         spin_lock_init(&sc->lock);
 400         INIT_LIST_HEAD(&sc->list);
 401         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
 402 }
 403
 404 static void
 405 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
 406 {
 407         rpc_destroy_wait_queue(&sc->wait);
 408 }
 409
 410 /*
 411  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 412  * create a new state_owner.
 413  *
 414  */
 415 static struct nfs4_state_owner *
 416 nfs4_alloc_state_owner(struct nfs_server *server,
 417                 struct rpc_cred *cred,
 418                 gfp_t gfp_flags)
 419 {
 420         struct nfs4_state_owner *sp;
 421
 422         sp = kzalloc(sizeof(*sp), gfp_flags);
 423         if (!sp)
 424                 return NULL;
 425         sp->so_server = server;
 426         sp->so_cred = get_rpccred(cred);
 427         spin_lock_init(&sp->so_lock);
 428         INIT_LIST_HEAD(&sp->so_states);
 429         nfs4_init_seqid_counter(&sp->so_seqid);
 430         atomic_set(&sp->so_count, 1);
 431         INIT_LIST_HEAD(&sp->so_lru);
 432         return sp;
 433 }
 434
 435 static void
 436 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 437 {
 438         struct rb_node *rb_node = &sp->so_server_node;
 439
 440         if (!RB_EMPTY_NODE(rb_node)) {
 441                 struct nfs_server *server = sp->so_server;
 442                 struct nfs_client *clp = server->nfs_client;
 443
 444                 spin_lock(&clp->cl_lock);
 445                 if (!RB_EMPTY_NODE(rb_node)) {
 446                         rb_erase(rb_node, &server->state_owners);
 447                         RB_CLEAR_NODE(rb_node);
 448                 }
 449                 spin_unlock(&clp->cl_lock);
 450         }
 451 }
 452
 453 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 454 {
 455         nfs4_destroy_seqid_counter(&sp->so_seqid);
 456         put_rpccred(sp->so_cred);
 457         kfree(sp);
 458 }
 459
 460 static void nfs4_gc_state_owners(struct nfs_server *server)
 461 {
 462         struct nfs_client *clp = server->nfs_client;
 463         struct nfs4_state_owner *sp, *tmp;
 464         unsigned long time_min, time_max;
 465         LIST_HEAD(doomed);
 466
 467         spin_lock(&clp->cl_lock);
 468         time_max = jiffies;
 469         time_min = (long)time_max - (long)clp->cl_lease_time;
 470         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 471                 /* NB: LRU is sorted so that oldest is at the head */
 472                 if (time_in_range(sp->so_expires, time_min, time_max))
 473                         break;
 474                 list_move(&sp->so_lru, &doomed);
 475                 nfs4_remove_state_owner_locked(sp);
 476         }
 477         spin_unlock(&clp->cl_lock);
 478
 479         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 480                 list_del(&sp->so_lru);
 481                 nfs4_free_state_owner(sp);
 482         }
 483 }
 484
 485 /**
 486  * nfs4_get_state_owner - Look up a state owner given a credential
 487  * @server: nfs_server to search
 488  * @cred: RPC credential to match
 489  *
 490  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 491  */
 492 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 493                                               struct rpc_cred *cred,
 494                                               gfp_t gfp_flags)
 495 {
 496         struct nfs_client *clp = server->nfs_client;
 497         struct nfs4_state_owner *sp, *new;
 498
 499         spin_lock(&clp->cl_lock);
 500         sp = nfs4_find_state_owner_locked(server, cred);
 501         spin_unlock(&clp->cl_lock);
 502         if (sp != NULL)
 503                 goto out;
 504         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 505         if (new == NULL)
 506                 goto out;
 507         do {
 508                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
 509                         break;
 510                 spin_lock(&clp->cl_lock);
 511                 sp = nfs4_insert_state_owner_locked(new);
 512                 spin_unlock(&clp->cl_lock);
 513         } while (sp == ERR_PTR(-EAGAIN));
 514         if (sp != new)
 515                 nfs4_free_state_owner(new);
 516 out:
 517         nfs4_gc_state_owners(server);
 518         return sp;
 519 }
 520
 521 /**
 522  * nfs4_put_state_owner - Release a nfs4_state_owner
 523  * @sp: state owner data to release
 524  */
 525 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 526 {
 527         struct nfs_server *server = sp->so_server;
 528         struct nfs_client *clp = server->nfs_client;
 529
 530         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 531                 return;
 532
 533         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
 534                 sp->so_expires = jiffies;
 535                 list_add_tail(&sp->so_lru, &server->state_owners_lru);
 536                 spin_unlock(&clp->cl_lock);
 537         } else {
 538                 nfs4_remove_state_owner_locked(sp);
 539                 spin_unlock(&clp->cl_lock);
 540                 nfs4_free_state_owner(sp);
 541         }
 542 }
 543
 544 /**
 545  * nfs4_purge_state_owners - Release all cached state owners
 546  * @server: nfs_server with cached state owners to release
 547  *
 548  * Called at umount time.  Remaining state owners will be on
 549  * the LRU with ref count of zero.
 550  */
 551 void nfs4_purge_state_owners(struct nfs_server *server)
 552 {
 553         struct nfs_client *clp = server->nfs_client;
 554         struct nfs4_state_owner *sp, *tmp;
 555         LIST_HEAD(doomed);
 556
 557         spin_lock(&clp->cl_lock);
 558         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 559                 list_move(&sp->so_lru, &doomed);
 560                 nfs4_remove_state_owner_locked(sp);
 561         }
 562         spin_unlock(&clp->cl_lock);
 563
 564         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 565                 list_del(&sp->so_lru);
 566                 nfs4_free_state_owner(sp);
 567         }
 568 }
 569
 570 static struct nfs4_state *
 571 nfs4_alloc_open_state(void)
 572 {
 573         struct nfs4_state *state;
 574
 575         state = kzalloc(sizeof(*state), GFP_NOFS);
 576         if (!state)
 577                 return NULL;
 578         atomic_set(&state->count, 1);
 579         INIT_LIST_HEAD(&state->lock_states);
 580         spin_lock_init(&state->state_lock);
 581         seqlock_init(&state->seqlock);
 582         return state;
 583 }
 584
 585 void
 586 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 587 {
 588         if (state->state == fmode)
 589                 return;
 590         /* NB! List reordering - see the reclaim code for why.  */
 591         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 592                 if (fmode & FMODE_WRITE)
 593                         list_move(&state->open_states, &state->owner->so_states);
 594                 else
 595                         list_move_tail(&state->open_states, &state->owner->so_states);
 596         }
 597         state->state = fmode;
 598 }
 599
 600 static struct nfs4_state *
 601 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 602 {
 603         struct nfs_inode *nfsi = NFS_I(inode);
 604         struct nfs4_state *state;
 605
 606         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 607                 if (state->owner != owner)
 608                         continue;
 609                 if (atomic_inc_not_zero(&state->count))
 610                         return state;
 611         }
 612         return NULL;
 613 }
 614
 615 static void
 616 nfs4_free_open_state(struct nfs4_state *state)
 617 {
 618         kfree(state);
 619 }
 620
 621 struct nfs4_state *
 622 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 623 {
 624         struct nfs4_state *state, *new;
 625         struct nfs_inode *nfsi = NFS_I(inode);
 626
 627         spin_lock(&inode->i_lock);
 628         state = __nfs4_find_state_byowner(inode, owner);
 629         spin_unlock(&inode->i_lock);
 630         if (state)
 631                 goto out;
 632         new = nfs4_alloc_open_state();
 633         spin_lock(&owner->so_lock);
 634         spin_lock(&inode->i_lock);
 635         state = __nfs4_find_state_byowner(inode, owner);
 636         if (state == NULL && new != NULL) {
 637                 state = new;
 638                 state->owner = owner;
 639                 atomic_inc(&owner->so_count);
 640                 list_add(&state->inode_states, &nfsi->open_states);
 641                 ihold(inode);
 642                 state->inode = inode;
 643                 spin_unlock(&inode->i_lock);
 644                 /* Note: The reclaim code dictates that we add stateless
 645                  * and read-only stateids to the end of the list */
 646                 list_add_tail(&state->open_states, &owner->so_states);
 647                 spin_unlock(&owner->so_lock);
 648         } else {
 649                 spin_unlock(&inode->i_lock);
 650                 spin_unlock(&owner->so_lock);
 651                 if (new)
 652                         nfs4_free_open_state(new);
 653         }
 654 out:
 655         return state;
 656 }
 657
 658 void nfs4_put_open_state(struct nfs4_state *state)
 659 {
 660         struct inode *inode = state->inode;
 661         struct nfs4_state_owner *owner = state->owner;
 662
 663         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 664                 return;
 665         spin_lock(&inode->i_lock);
 666         list_del(&state->inode_states);
 667         list_del(&state->open_states);
 668         spin_unlock(&inode->i_lock);
 669         spin_unlock(&owner->so_lock);
 670         iput(inode);
 671         nfs4_free_open_state(state);
 672         nfs4_put_state_owner(owner);
 673 }
 674
 675 /*
 676  * Close the current file.
 677  */
 678 static void __nfs4_close(struct nfs4_state *state,
 679                 fmode_t fmode, gfp_t gfp_mask, int wait)
 680 {
 681         struct nfs4_state_owner *owner = state->owner;
 682         int call_close = 0;
 683         fmode_t newstate;
 684
 685         atomic_inc(&owner->so_count);
 686         /* Protect against nfs4_find_state() */
 687         spin_lock(&owner->so_lock);
 688         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 689                 case FMODE_READ:
 690                         state->n_rdonly--;
 691                         break;
 692                 case FMODE_WRITE:
 693                         state->n_wronly--;
 694                         break;
 695                 case FMODE_READ|FMODE_WRITE:
 696                         state->n_rdwr--;
 697         }
 698         newstate = FMODE_READ|FMODE_WRITE;
 699         if (state->n_rdwr == 0) {
 700                 if (state->n_rdonly == 0) {
 701                         newstate &= ~FMODE_READ;
 702                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 703                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 704                 }
 705                 if (state->n_wronly == 0) {
 706                         newstate &= ~FMODE_WRITE;
 707                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 708                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 709                 }
 710                 if (newstate == 0)
 711                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 712         }
 713         nfs4_state_set_mode_locked(state, newstate);
 714         spin_unlock(&owner->so_lock);
 715
 716         if (!call_close) {
 717                 nfs4_put_open_state(state);
 718                 nfs4_put_state_owner(owner);
 719         } else {
 720                 bool roc = pnfs_roc(state->inode);
 721
 722                 nfs4_do_close(state, gfp_mask, wait, roc);
 723         }
 724 }
 725
 726 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 727 {
 728         __nfs4_close(state, fmode, GFP_NOFS, 0);
 729 }
 730
 731 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 732 {
 733         __nfs4_close(state, fmode, GFP_KERNEL, 1);
 734 }
 735
 736 /*
 737  * Search the state->lock_states for an existing lock_owner
 738  * that is compatible with current->files
 739  */
 740 static struct nfs4_lock_state *
 741 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 742 {
 743         struct nfs4_lock_state *pos;
 744         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 745                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
 746                         continue;
 747                 switch (pos->ls_owner.lo_type) {
 748                 case NFS4_POSIX_LOCK_TYPE:
 749                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
 750                                 continue;
 751                         break;
 752                 case NFS4_FLOCK_LOCK_TYPE:
 753                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
 754                                 continue;
 755                 }
 756                 atomic_inc(&pos->ls_count);
 757                 return pos;
 758         }
 759         return NULL;
 760 }
 761
 762 /*
 763  * Return a compatible lock_state. If no initialized lock_state structure
 764  * exists, return an uninitialized one.
 765  *
 766  */
 767 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)
 768 {
 769         struct nfs4_lock_state *lsp;
 770         struct nfs_server *server = state->owner->so_server;
 771
 772         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 773         if (lsp == NULL)
 774                 return NULL;
 775         nfs4_init_seqid_counter(&lsp->ls_seqid);
 776         atomic_set(&lsp->ls_count, 1);
 777         lsp->ls_state = state;
 778         lsp->ls_owner.lo_type = type;
 779         switch (lsp->ls_owner.lo_type) {
 780         case NFS4_FLOCK_LOCK_TYPE:
 781                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
 782                 break;
 783         case NFS4_POSIX_LOCK_TYPE:
 784                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
 785                 break;
 786         default:
 787                 goto out_free;
 788         }
 789         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
 790         if (lsp->ls_seqid.owner_id < 0)
 791                 goto out_free;
 792         INIT_LIST_HEAD(&lsp->ls_locks);
 793         return lsp;
 794 out_free:
 795         kfree(lsp);
 796         return NULL;
 797 }
 798
 799 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
 800 {
 801         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
 802         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
 803         kfree(lsp);
 804 }
 805
 806 /*
 807  * Return a compatible lock_state. If no initialized lock_state structure
 808  * exists, return an uninitialized one.
 809  *
 810  */
 811 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
 812 {
 813         struct nfs4_lock_state *lsp, *new = NULL;
 814
 815         for(;;) {
 816                 spin_lock(&state->state_lock);
 817                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
 818                 if (lsp != NULL)
 819                         break;
 820                 if (new != NULL) {
 821                         list_add(&new->ls_locks, &state->lock_states);
 822                         set_bit(LK_STATE_IN_USE, &state->flags);
 823                         lsp = new;
 824                         new = NULL;
 825                         break;
 826                 }
 827                 spin_unlock(&state->state_lock);
 828                 new = nfs4_alloc_lock_state(state, owner, pid, type);
 829                 if (new == NULL)
 830                         return NULL;
 831         }
 832         spin_unlock(&state->state_lock);
 833         if (new != NULL)
 834                 nfs4_free_lock_state(state->owner->so_server, new);
 835         return lsp;
 836 }
 837
 838 /*
 839  * Release reference to lock_state, and free it if we see that
 840  * it is no longer in use
 841  */
 842 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 843 {
 844         struct nfs4_state *state;
 845
 846         if (lsp == NULL)
 847                 return;
 848         state = lsp->ls_state;
 849         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 850                 return;
 851         list_del(&lsp->ls_locks);
 852         if (list_empty(&state->lock_states))
 853                 clear_bit(LK_STATE_IN_USE, &state->flags);
 854         spin_unlock(&state->state_lock);
 855         if (lsp->ls_flags & NFS_LOCK_INITIALIZED) {
 856                 if (nfs4_release_lockowner(lsp) == 0)
 857                         return;
 858         }
 859         nfs4_free_lock_state(lsp->ls_state->owner->so_server, lsp);
 860 }
 861
 862 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 863 {
 864         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 865
 866         dst->fl_u.nfs4_fl.owner = lsp;
 867         atomic_inc(&lsp->ls_count);
 868 }
 869
 870 static void nfs4_fl_release_lock(struct file_lock *fl)
 871 {
 872         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 873 }
 874
 875 static const struct file_lock_operations nfs4_fl_lock_ops = {
 876         .fl_copy_lock = nfs4_fl_copy_lock,
 877         .fl_release_private = nfs4_fl_release_lock,
 878 };
 879
 880 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 881 {
 882         struct nfs4_lock_state *lsp;
 883
 884         if (fl->fl_ops != NULL)
 885                 return 0;
 886         if (fl->fl_flags & FL_POSIX)
 887                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
 888         else if (fl->fl_flags & FL_FLOCK)
 889                 lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
 890                                 NFS4_FLOCK_LOCK_TYPE);
 891         else
 892                 return -EINVAL;
 893         if (lsp == NULL)
 894                 return -ENOMEM;
 895         fl->fl_u.nfs4_fl.owner = lsp;
 896         fl->fl_ops = &nfs4_fl_lock_ops;
 897         return 0;
 898 }
 899
 900 static bool nfs4_copy_lock_stateid(nfs4_stateid *dst, struct nfs4_state *state,
 901                 fl_owner_t fl_owner, pid_t fl_pid)
 902 {
 903         struct nfs4_lock_state *lsp;
 904         bool ret = false;
 905
 906         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 907                 goto out;
 908
 909         spin_lock(&state->state_lock);
 910         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
 911         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0) {
 912                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
 913                 ret = true;
 914         }
 915         spin_unlock(&state->state_lock);
 916         nfs4_put_lock_state(lsp);
 917 out:
 918         return ret;
 919 }
 920
 921 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
 922 {
 923         int seq;
 924
 925         do {
 926                 seq = read_seqbegin(&state->seqlock);
 927                 nfs4_stateid_copy(dst, &state->stateid);
 928         } while (read_seqretry(&state->seqlock, seq));
 929 }
 930
 931 /*
 932  * Byte-range lock aware utility to initialize the stateid of read/write
 933  * requests.
 934  */
 935 void nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
 936                 fmode_t fmode, fl_owner_t fl_owner, pid_t fl_pid)
 937 {
 938         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
 939                 return;
 940         if (nfs4_copy_lock_stateid(dst, state, fl_owner, fl_pid))
 941                 return;
 942         nfs4_copy_open_stateid(dst, state);
 943 }
 944
 945 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
 946 {
 947         struct nfs_seqid *new;
 948
 949         new = kmalloc(sizeof(*new), gfp_mask);
 950         if (new != NULL) {
 951                 new->sequence = counter;
 952                 INIT_LIST_HEAD(&new->list);
 953                 new->task = NULL;
 954         }
 955         return new;
 956 }
 957
 958 void nfs_release_seqid(struct nfs_seqid *seqid)
 959 {
 960         struct nfs_seqid_counter *sequence;
 961
 962         if (list_empty(&seqid->list))
 963                 return;
 964         sequence = seqid->sequence;
 965         spin_lock(&sequence->lock);
 966         list_del_init(&seqid->list);
 967         if (!list_empty(&sequence->list)) {
 968                 struct nfs_seqid *next;
 969
 970                 next = list_first_entry(&sequence->list,
 971                                 struct nfs_seqid, list);
 972                 rpc_wake_up_queued_task(&sequence->wait, next->task);
 973         }
 974         spin_unlock(&sequence->lock);
 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->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                         pr_warn_ratelimited("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 nfs_seqid_counter *sequence = seqid->sequence;
1042         int status = 0;
1043
1044         spin_lock(&sequence->lock);
1045         seqid->task = task;
1046         if (list_empty(&seqid->list))
1047                 list_add_tail(&seqid->list, &sequence->list);
1048         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1049                 goto unlock;
1050         rpc_sleep_on(&sequence->wait, task, NULL);
1051         status = -EAGAIN;
1052 unlock:
1053         spin_unlock(&sequence->lock);
1054         return status;
1055 }
1056
1057 static int nfs4_run_state_manager(void *);
1058
1059 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1060 {
1061         smp_mb__before_clear_bit();
1062         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1063         smp_mb__after_clear_bit();
1064         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1065         rpc_wake_up(&clp->cl_rpcwaitq);
1066 }
1067
1068 /*
1069  * Schedule the nfs_client asynchronous state management routine
1070  */
1071 void nfs4_schedule_state_manager(struct nfs_client *clp)
1072 {
1073         struct task_struct *task;
1074         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1075
1076         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1077                 return;
1078         __module_get(THIS_MODULE);
1079         atomic_inc(&clp->cl_count);
1080
1081         /* The rcu_read_lock() is not strictly necessary, as the state
1082          * manager is the only thread that ever changes the rpc_xprt
1083          * after it's initialized.  At this point, we're single threaded. */
1084         rcu_read_lock();
1085         snprintf(buf, sizeof(buf), "%s-manager",
1086                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1087         rcu_read_unlock();
1088         task = kthread_run(nfs4_run_state_manager, clp, buf);
1089         if (IS_ERR(task)) {
1090                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1091                         __func__, PTR_ERR(task));
1092                 nfs4_clear_state_manager_bit(clp);
1093                 nfs_put_client(clp);
1094                 module_put(THIS_MODULE);
1095         }
1096 }
1097
1098 /*
1099  * Schedule a lease recovery attempt
1100  */
1101 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1102 {
1103         if (!clp)
1104                 return;
1105         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1106                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1107         nfs4_schedule_state_manager(clp);
1108 }
1109 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1110
1111 /*
1112  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1113  * @clp: client to process
1114  *
1115  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1116  * resend of the SETCLIENTID and hence re-establish the
1117  * callback channel. Then return all existing delegations.
1118  */
1119 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1120 {
1121         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1122         nfs_expire_all_delegations(clp);
1123 }
1124
1125 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1126 {
1127         nfs40_handle_cb_pathdown(clp);
1128         nfs4_schedule_state_manager(clp);
1129 }
1130
1131 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1132 {
1133
1134         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1135         /* Don't recover state that expired before the reboot */
1136         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1137                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1138                 return 0;
1139         }
1140         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1141         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1142         return 1;
1143 }
1144
1145 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1146 {
1147         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1148         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1149         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1150         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1151         return 1;
1152 }
1153
1154 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1155 {
1156         struct nfs_client *clp = server->nfs_client;
1157
1158         nfs4_state_mark_reclaim_nograce(clp, state);
1159         nfs4_schedule_state_manager(clp);
1160 }
1161 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1162
1163 void nfs_inode_find_state_and_recover(struct inode *inode,
1164                 const nfs4_stateid *stateid)
1165 {
1166         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1167         struct nfs_inode *nfsi = NFS_I(inode);
1168         struct nfs_open_context *ctx;
1169         struct nfs4_state *state;
1170         bool found = false;
1171
1172         spin_lock(&inode->i_lock);
1173         list_for_each_entry(ctx, &nfsi->open_files, list) {
1174                 state = ctx->state;
1175                 if (state == NULL)
1176                         continue;
1177                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1178                         continue;
1179                 if (!nfs4_stateid_match(&state->stateid, stateid))
1180                         continue;
1181                 nfs4_state_mark_reclaim_nograce(clp, state);
1182                 found = true;
1183         }
1184         spin_unlock(&inode->i_lock);
1185         if (found)
1186                 nfs4_schedule_state_manager(clp);
1187 }
1188
1189
1190 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1191 {
1192         struct inode *inode = state->inode;
1193         struct nfs_inode *nfsi = NFS_I(inode);
1194         struct file_lock *fl;
1195         int status = 0;
1196
1197         if (inode->i_flock == NULL)
1198                 return 0;
1199
1200         /* Guard against delegation returns and new lock/unlock calls */
1201         down_write(&nfsi->rwsem);
1202         /* Protect inode->i_flock using the BKL */
1203         lock_flocks();
1204         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1205                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1206                         continue;
1207                 if (nfs_file_open_context(fl->fl_file)->state != state)
1208                         continue;
1209                 unlock_flocks();
1210                 status = ops->recover_lock(state, fl);
1211                 switch (status) {
1212                         case 0:
1213                                 break;
1214                         case -ESTALE:
1215                         case -NFS4ERR_ADMIN_REVOKED:
1216                         case -NFS4ERR_STALE_STATEID:
1217                         case -NFS4ERR_BAD_STATEID:
1218                         case -NFS4ERR_EXPIRED:
1219                         case -NFS4ERR_NO_GRACE:
1220                         case -NFS4ERR_STALE_CLIENTID:
1221                         case -NFS4ERR_BADSESSION:
1222                         case -NFS4ERR_BADSLOT:
1223                         case -NFS4ERR_BAD_HIGH_SLOT:
1224                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1225                                 goto out;
1226                         default:
1227                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1228                                         "Zeroing state\n", __func__, status);
1229                         case -ENOMEM:
1230                         case -NFS4ERR_DENIED:
1231                         case -NFS4ERR_RECLAIM_BAD:
1232                         case -NFS4ERR_RECLAIM_CONFLICT:
1233                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1234                                 status = 0;
1235                 }
1236                 lock_flocks();
1237         }
1238         unlock_flocks();
1239 out:
1240         up_write(&nfsi->rwsem);
1241         return status;
1242 }
1243
1244 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1245 {
1246         struct nfs4_state *state;
1247         struct nfs4_lock_state *lock;
1248         int status = 0;
1249
1250         /* Note: we rely on the sp->so_states list being ordered
1251          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1252          * states first.
1253          * This is needed to ensure that the server won't give us any
1254          * read delegations that we have to return if, say, we are
1255          * recovering after a network partition or a reboot from a
1256          * server that doesn't support a grace period.
1257          */
1258 restart:
1259         spin_lock(&sp->so_lock);
1260         list_for_each_entry(state, &sp->so_states, open_states) {
1261                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1262                         continue;
1263                 if (state->state == 0)
1264                         continue;
1265                 atomic_inc(&state->count);
1266                 spin_unlock(&sp->so_lock);
1267                 status = ops->recover_open(sp, state);
1268                 if (status >= 0) {
1269                         status = nfs4_reclaim_locks(state, ops);
1270                         if (status >= 0) {
1271                                 spin_lock(&state->state_lock);
1272                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1273                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1274                                                 pr_warn_ratelimited("NFS: "
1275                                                         "%s: Lock reclaim "
1276                                                         "failed!\n", __func__);
1277                                 }
1278                                 spin_unlock(&state->state_lock);
1279                                 nfs4_put_open_state(state);
1280                                 goto restart;
1281                         }
1282                 }
1283                 switch (status) {
1284                         default:
1285                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1286                                         "Zeroing state\n", __func__, status);
1287                         case -ENOENT:
1288                         case -ENOMEM:
1289                         case -ESTALE:
1290                                 /*
1291                                  * Open state on this file cannot be recovered
1292                                  * All we can do is revert to using the zero stateid.
1293                                  */
1294                                 memset(&state->stateid, 0,
1295                                         sizeof(state->stateid));
1296                                 /* Mark the file as being 'closed' */
1297                                 state->state = 0;
1298                                 break;
1299                         case -EKEYEXPIRED:
1300                                 /*
1301                                  * User RPCSEC_GSS context has expired.
1302                                  * We cannot recover this stateid now, so
1303                                  * skip it and allow recovery thread to
1304                                  * proceed.
1305                                  */
1306                                 break;
1307                         case -NFS4ERR_ADMIN_REVOKED:
1308                         case -NFS4ERR_STALE_STATEID:
1309                         case -NFS4ERR_BAD_STATEID:
1310                         case -NFS4ERR_RECLAIM_BAD:
1311                         case -NFS4ERR_RECLAIM_CONFLICT:
1312                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1313                                 break;
1314                         case -NFS4ERR_EXPIRED:
1315                         case -NFS4ERR_NO_GRACE:
1316                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1317                         case -NFS4ERR_STALE_CLIENTID:
1318                         case -NFS4ERR_BADSESSION:
1319                         case -NFS4ERR_BADSLOT:
1320                         case -NFS4ERR_BAD_HIGH_SLOT:
1321                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1322                                 goto out_err;
1323                 }
1324                 nfs4_put_open_state(state);
1325                 goto restart;
1326         }
1327         spin_unlock(&sp->so_lock);
1328         return 0;
1329 out_err:
1330         nfs4_put_open_state(state);
1331         return status;
1332 }
1333
1334 static void nfs4_clear_open_state(struct nfs4_state *state)
1335 {
1336         struct nfs4_lock_state *lock;
1337
1338         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1339         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1340         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1341         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1342         spin_lock(&state->state_lock);
1343         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1344                 lock->ls_seqid.flags = 0;
1345                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1346         }
1347         spin_unlock(&state->state_lock);
1348 }
1349
1350 static void nfs4_reset_seqids(struct nfs_server *server,
1351         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1352 {
1353         struct nfs_client *clp = server->nfs_client;
1354         struct nfs4_state_owner *sp;
1355         struct rb_node *pos;
1356         struct nfs4_state *state;
1357
1358         spin_lock(&clp->cl_lock);
1359         for (pos = rb_first(&server->state_owners);
1360              pos != NULL;
1361              pos = rb_next(pos)) {
1362                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1363                 sp->so_seqid.flags = 0;
1364                 spin_lock(&sp->so_lock);
1365                 list_for_each_entry(state, &sp->so_states, open_states) {
1366                         if (mark_reclaim(clp, state))
1367                                 nfs4_clear_open_state(state);
1368                 }
1369                 spin_unlock(&sp->so_lock);
1370         }
1371         spin_unlock(&clp->cl_lock);
1372 }
1373
1374 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1375         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1376 {
1377         struct nfs_server *server;
1378
1379         rcu_read_lock();
1380         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1381                 nfs4_reset_seqids(server, mark_reclaim);
1382         rcu_read_unlock();
1383 }
1384
1385 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1386 {
1387         /* Mark all delegations for reclaim */
1388         nfs_delegation_mark_reclaim(clp);
1389         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1390 }
1391
1392 static void nfs4_reclaim_complete(struct nfs_client *clp,
1393                                  const struct nfs4_state_recovery_ops *ops)
1394 {
1395         /* Notify the server we're done reclaiming our state */
1396         if (ops->reclaim_complete)
1397                 (void)ops->reclaim_complete(clp);
1398 }
1399
1400 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1401 {
1402         struct nfs_client *clp = server->nfs_client;
1403         struct nfs4_state_owner *sp;
1404         struct rb_node *pos;
1405         struct nfs4_state *state;
1406
1407         spin_lock(&clp->cl_lock);
1408         for (pos = rb_first(&server->state_owners);
1409              pos != NULL;
1410              pos = rb_next(pos)) {
1411                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1412                 spin_lock(&sp->so_lock);
1413                 list_for_each_entry(state, &sp->so_states, open_states) {
1414                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1415                                                 &state->flags))
1416                                 continue;
1417                         nfs4_state_mark_reclaim_nograce(clp, state);
1418                 }
1419                 spin_unlock(&sp->so_lock);
1420         }
1421         spin_unlock(&clp->cl_lock);
1422 }
1423
1424 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1425 {
1426         struct nfs_server *server;
1427
1428         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1429                 return 0;
1430
1431         rcu_read_lock();
1432         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1433                 nfs4_clear_reclaim_server(server);
1434         rcu_read_unlock();
1435
1436         nfs_delegation_reap_unclaimed(clp);
1437         return 1;
1438 }
1439
1440 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1441 {
1442         if (!nfs4_state_clear_reclaim_reboot(clp))
1443                 return;
1444         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1445 }
1446
1447 static void nfs_delegation_clear_all(struct nfs_client *clp)
1448 {
1449         nfs_delegation_mark_reclaim(clp);
1450         nfs_delegation_reap_unclaimed(clp);
1451 }
1452
1453 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1454 {
1455         nfs_delegation_clear_all(clp);
1456         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1457 }
1458
1459 static void nfs4_warn_keyexpired(const char *s)
1460 {
1461         printk_ratelimited(KERN_WARNING "Error: state manager"
1462                         " encountered RPCSEC_GSS session"
1463                         " expired against NFSv4 server %s.\n",
1464                         s);
1465 }
1466
1467 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1468 {
1469         switch (error) {
1470                 case 0:
1471                         break;
1472                 case -NFS4ERR_CB_PATH_DOWN:
1473                         nfs40_handle_cb_pathdown(clp);
1474                         break;
1475                 case -NFS4ERR_NO_GRACE:
1476                         nfs4_state_end_reclaim_reboot(clp);
1477                         break;
1478                 case -NFS4ERR_STALE_CLIENTID:
1479                 case -NFS4ERR_LEASE_MOVED:
1480                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1481                         nfs4_state_clear_reclaim_reboot(clp);
1482                         nfs4_state_start_reclaim_reboot(clp);
1483                         break;
1484                 case -NFS4ERR_EXPIRED:
1485                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1486                         nfs4_state_start_reclaim_nograce(clp);
1487                         break;
1488                 case -NFS4ERR_BADSESSION:
1489                 case -NFS4ERR_BADSLOT:
1490                 case -NFS4ERR_BAD_HIGH_SLOT:
1491                 case -NFS4ERR_DEADSESSION:
1492                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1493                 case -NFS4ERR_SEQ_FALSE_RETRY:
1494                 case -NFS4ERR_SEQ_MISORDERED:
1495                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1496                         /* Zero session reset errors */
1497                         break;
1498                 case -EKEYEXPIRED:
1499                         /* Nothing we can do */
1500                         nfs4_warn_keyexpired(clp->cl_hostname);
1501                         break;
1502                 default:
1503                         return error;
1504         }
1505         return 0;
1506 }
1507
1508 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1509 {
1510         struct nfs4_state_owner *sp;
1511         struct nfs_server *server;
1512         struct rb_node *pos;
1513         int status = 0;
1514
1515 restart:
1516         rcu_read_lock();
1517         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1518                 nfs4_purge_state_owners(server);
1519                 spin_lock(&clp->cl_lock);
1520                 for (pos = rb_first(&server->state_owners);
1521                      pos != NULL;
1522                      pos = rb_next(pos)) {
1523                         sp = rb_entry(pos,
1524                                 struct nfs4_state_owner, so_server_node);
1525                         if (!test_and_clear_bit(ops->owner_flag_bit,
1526                                                         &sp->so_flags))
1527                                 continue;
1528                         atomic_inc(&sp->so_count);
1529                         spin_unlock(&clp->cl_lock);
1530                         rcu_read_unlock();
1531
1532                         status = nfs4_reclaim_open_state(sp, ops);
1533                         if (status < 0) {
1534                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1535                                 nfs4_put_state_owner(sp);
1536                                 return nfs4_recovery_handle_error(clp, status);
1537                         }
1538
1539                         nfs4_put_state_owner(sp);
1540                         goto restart;
1541                 }
1542                 spin_unlock(&clp->cl_lock);
1543         }
1544         rcu_read_unlock();
1545         return status;
1546 }
1547
1548 static int nfs4_check_lease(struct nfs_client *clp)
1549 {
1550         struct rpc_cred *cred;
1551         const struct nfs4_state_maintenance_ops *ops =
1552                 clp->cl_mvops->state_renewal_ops;
1553         int status;
1554
1555         /* Is the client already known to have an expired lease? */
1556         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1557                 return 0;
1558         spin_lock(&clp->cl_lock);
1559         cred = ops->get_state_renewal_cred_locked(clp);
1560         spin_unlock(&clp->cl_lock);
1561         if (cred == NULL) {
1562                 cred = nfs4_get_setclientid_cred(clp);
1563                 status = -ENOKEY;
1564                 if (cred == NULL)
1565                         goto out;
1566         }
1567         status = ops->renew_lease(clp, cred);
1568         put_rpccred(cred);
1569 out:
1570         return nfs4_recovery_handle_error(clp, status);
1571 }
1572
1573 static int nfs4_reclaim_lease(struct nfs_client *clp)
1574 {
1575         struct rpc_cred *cred;
1576         const struct nfs4_state_recovery_ops *ops =
1577                 clp->cl_mvops->reboot_recovery_ops;
1578         int status = -ENOENT;
1579
1580         cred = ops->get_clid_cred(clp);
1581         if (cred != NULL) {
1582                 status = ops->establish_clid(clp, cred);
1583                 put_rpccred(cred);
1584                 /* Handle case where the user hasn't set up machine creds */
1585                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1586                         nfs4_clear_machine_cred(clp);
1587                         status = -EAGAIN;
1588                 }
1589                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1590                         status = -EPROTONOSUPPORT;
1591         }
1592         return status;
1593 }
1594
1595 #ifdef CONFIG_NFS_V4_1
1596 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1597 {
1598         struct nfs_client *clp = session->clp;
1599
1600         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1601         nfs4_schedule_lease_recovery(clp);
1602 }
1603 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1604
1605 void nfs41_handle_recall_slot(struct nfs_client *clp)
1606 {
1607         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1608         nfs4_schedule_state_manager(clp);
1609 }
1610
1611 static void nfs4_reset_all_state(struct nfs_client *clp)
1612 {
1613         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1614                 clp->cl_boot_time = CURRENT_TIME;
1615                 nfs4_state_start_reclaim_nograce(clp);
1616                 nfs4_schedule_state_manager(clp);
1617         }
1618 }
1619
1620 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1621 {
1622         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1623                 nfs4_state_start_reclaim_reboot(clp);
1624                 nfs4_schedule_state_manager(clp);
1625         }
1626 }
1627
1628 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1629 {
1630         /* Temporary */
1631         nfs4_reset_all_state(clp);
1632 }
1633
1634 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1635 {
1636         /* This will need to handle layouts too */
1637         nfs_expire_all_delegations(clp);
1638 }
1639
1640 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1641 {
1642         nfs_expire_all_delegations(clp);
1643         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1644                 nfs4_schedule_state_manager(clp);
1645 }
1646
1647 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1648 {
1649         if (!flags)
1650                 return;
1651         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1652                 nfs41_handle_server_reboot(clp);
1653         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1654                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1655                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1656                             SEQ4_STATUS_LEASE_MOVED))
1657                 nfs41_handle_state_revoked(clp);
1658         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1659                 nfs41_handle_recallable_state_revoked(clp);
1660         if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1661                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1662                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1663                 nfs41_handle_cb_path_down(clp);
1664 }
1665
1666 static int nfs4_reset_session(struct nfs_client *clp)
1667 {
1668         int status;
1669
1670         nfs4_begin_drain_session(clp);
1671         status = nfs4_proc_destroy_session(clp->cl_session);
1672         if (status && status != -NFS4ERR_BADSESSION &&
1673             status != -NFS4ERR_DEADSESSION) {
1674                 status = nfs4_recovery_handle_error(clp, status);
1675                 goto out;
1676         }
1677
1678         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1679         status = nfs4_proc_create_session(clp);
1680         if (status) {
1681                 status = nfs4_recovery_handle_error(clp, status);
1682                 goto out;
1683         }
1684         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1685         /* create_session negotiated new slot table */
1686         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1687
1688          /* Let the state manager reestablish state */
1689         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1690                 nfs41_setup_state_renewal(clp);
1691 out:
1692         return status;
1693 }
1694
1695 static int nfs4_recall_slot(struct nfs_client *clp)
1696 {
1697         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1698         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1699         struct nfs4_slot *new, *old;
1700         int i;
1701
1702         nfs4_begin_drain_session(clp);
1703         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1704                       GFP_NOFS);
1705         if (!new)
1706                 return -ENOMEM;
1707
1708         spin_lock(&fc_tbl->slot_tbl_lock);
1709         for (i = 0; i < fc_tbl->target_max_slots; i++)
1710                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1711         old = fc_tbl->slots;
1712         fc_tbl->slots = new;
1713         fc_tbl->max_slots = fc_tbl->target_max_slots;
1714         fc_tbl->target_max_slots = 0;
1715         fc_attrs->max_reqs = fc_tbl->max_slots;
1716         spin_unlock(&fc_tbl->slot_tbl_lock);
1717
1718         kfree(old);
1719         nfs4_end_drain_session(clp);
1720         return 0;
1721 }
1722
1723 #else /* CONFIG_NFS_V4_1 */
1724 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1725 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1726 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1727 #endif /* CONFIG_NFS_V4_1 */
1728
1729 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1730  * on EXCHANGE_ID for v4.1
1731  */
1732 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1733 {
1734         switch (status) {
1735         case -NFS4ERR_CLID_INUSE:
1736         case -NFS4ERR_STALE_CLIENTID:
1737                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1738                 break;
1739         case -NFS4ERR_DELAY:
1740         case -ETIMEDOUT:
1741         case -EAGAIN:
1742                 ssleep(1);
1743                 break;
1744
1745         case -EKEYEXPIRED:
1746                 nfs4_warn_keyexpired(clp->cl_hostname);
1747         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1748                                  * in nfs4_exchange_id */
1749         default:
1750                 return;
1751         }
1752         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1753 }
1754
1755 static void nfs4_state_manager(struct nfs_client *clp)
1756 {
1757         int status = 0;
1758
1759         /* Ensure exclusive access to NFSv4 state */
1760         do {
1761                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1762                         /* We're going to have to re-establish a clientid */
1763                         status = nfs4_reclaim_lease(clp);
1764                         if (status) {
1765                                 nfs4_set_lease_expired(clp, status);
1766                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1767                                                         &clp->cl_state))
1768                                         continue;
1769                                 if (clp->cl_cons_state ==
1770                                                         NFS_CS_SESSION_INITING)
1771                                         nfs_mark_client_ready(clp, status);
1772                                 goto out_error;
1773                         }
1774                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1775
1776                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1777                                                &clp->cl_state))
1778                                 nfs4_state_start_reclaim_nograce(clp);
1779                         else
1780                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1781                                         &clp->cl_state);
1782
1783                         pnfs_destroy_all_layouts(clp);
1784                 }
1785
1786                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1787                         status = nfs4_check_lease(clp);
1788                         if (status < 0)
1789                                 goto out_error;
1790                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1791                                 continue;
1792                 }
1793
1794                 /* Initialize or reset the session */
1795                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1796                    && nfs4_has_session(clp)) {
1797                         status = nfs4_reset_session(clp);
1798                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1799                                 continue;
1800                         if (status < 0)
1801                                 goto out_error;
1802                 }
1803
1804                 /* First recover reboot state... */
1805                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1806                         status = nfs4_do_reclaim(clp,
1807                                 clp->cl_mvops->reboot_recovery_ops);
1808                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1809                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1810                                 continue;
1811                         nfs4_state_end_reclaim_reboot(clp);
1812                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1813                                 continue;
1814                         if (status < 0)
1815                                 goto out_error;
1816                 }
1817
1818                 /* Now recover expired state... */
1819                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1820                         status = nfs4_do_reclaim(clp,
1821                                 clp->cl_mvops->nograce_recovery_ops);
1822                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1823                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1824                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1825                                 continue;
1826                         if (status < 0)
1827                                 goto out_error;
1828                 }
1829
1830                 nfs4_end_drain_session(clp);
1831                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1832                         nfs_client_return_marked_delegations(clp);
1833                         continue;
1834                 }
1835                 /* Recall session slots */
1836                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1837                    && nfs4_has_session(clp)) {
1838                         status = nfs4_recall_slot(clp);
1839                         if (status < 0)
1840                                 goto out_error;
1841                         continue;
1842                 }
1843
1844
1845                 nfs4_clear_state_manager_bit(clp);
1846                 /* Did we race with an attempt to give us more work? */
1847                 if (clp->cl_state == 0)
1848                         break;
1849                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1850                         break;
1851         } while (atomic_read(&clp->cl_count) > 1);
1852         return;
1853 out_error:
1854         pr_warn_ratelimited("NFS: state manager failed on NFSv4 server %s"
1855                         " with error %d\n", clp->cl_hostname, -status);
1856         nfs4_end_drain_session(clp);
1857         nfs4_clear_state_manager_bit(clp);
1858 }
1859
1860 static int nfs4_run_state_manager(void *ptr)
1861 {
1862         struct nfs_client *clp = ptr;
1863
1864         allow_signal(SIGKILL);
1865         nfs4_state_manager(clp);
1866         nfs_put_client(clp);
1867         module_put_and_exit(0);
1868         return 0;
1869 }
1870
1871 /*
1872  * Local variables:
1873  *  c-basic-offset: 8
1874  * End:
1875  */