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         int err;
 409
 410         while (*p != NULL) {
 411                 parent = *p;
 412                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 413
 414                 if (new->so_cred < sp->so_cred)
 415                         p = &parent->rb_left;
 416                 else if (new->so_cred > sp->so_cred)
 417                         p = &parent->rb_right;
 418                 else {
 419                         if (!list_empty(&sp->so_lru))
 420                                 list_del_init(&sp->so_lru);
 421                         atomic_inc(&sp->so_count);
 422                         return sp;
 423                 }
 424         }
 425         err = ida_get_new(&server->openowner_id, &new->so_owner_id);
 426         if (err)
 427                 return ERR_PTR(err);
 428         rb_link_node(&new->so_server_node, parent, p);
 429         rb_insert_color(&new->so_server_node, &server->state_owners);
 430         return new;
 431 }
 432
 433 static void
 434 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 435 {
 436         struct nfs_server *server = sp->so_server;
 437
 438         if (!RB_EMPTY_NODE(&sp->so_server_node))
 439                 rb_erase(&sp->so_server_node, &server->state_owners);
 440         ida_remove(&server->openowner_id, sp->so_owner_id);
 441 }
 442
 443 /*
 444  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 445  * create a new state_owner.
 446  *
 447  */
 448 static struct nfs4_state_owner *
 449 nfs4_alloc_state_owner(struct nfs_server *server,
 450                 struct rpc_cred *cred,
 451                 gfp_t gfp_flags)
 452 {
 453         struct nfs4_state_owner *sp;
 454
 455         sp = kzalloc(sizeof(*sp), gfp_flags);
 456         if (!sp)
 457                 return NULL;
 458         sp->so_server = server;
 459         sp->so_cred = get_rpccred(cred);
 460         spin_lock_init(&sp->so_lock);
 461         INIT_LIST_HEAD(&sp->so_states);
 462         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 463         sp->so_seqid.sequence = &sp->so_sequence;
 464         spin_lock_init(&sp->so_sequence.lock);
 465         INIT_LIST_HEAD(&sp->so_sequence.list);
 466         atomic_set(&sp->so_count, 1);
 467         INIT_LIST_HEAD(&sp->so_lru);
 468         return sp;
 469 }
 470
 471 static void
 472 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 473 {
 474         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
 475                 struct nfs_server *server = sp->so_server;
 476                 struct nfs_client *clp = server->nfs_client;
 477
 478                 spin_lock(&clp->cl_lock);
 479                 rb_erase(&sp->so_server_node, &server->state_owners);
 480                 RB_CLEAR_NODE(&sp->so_server_node);
 481                 spin_unlock(&clp->cl_lock);
 482         }
 483 }
 484
 485 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 486 {
 487         rpc_destroy_wait_queue(&sp->so_sequence.wait);
 488         put_rpccred(sp->so_cred);
 489         kfree(sp);
 490 }
 491
 492 static void nfs4_gc_state_owners(struct nfs_server *server)
 493 {
 494         struct nfs_client *clp = server->nfs_client;
 495         struct nfs4_state_owner *sp, *tmp;
 496         unsigned long time_min, time_max;
 497         LIST_HEAD(doomed);
 498
 499         spin_lock(&clp->cl_lock);
 500         time_max = jiffies;
 501         time_min = (long)time_max - (long)clp->cl_lease_time;
 502         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 503                 /* NB: LRU is sorted so that oldest is at the head */
 504                 if (time_in_range(sp->so_expires, time_min, time_max))
 505                         break;
 506                 list_move(&sp->so_lru, &doomed);
 507                 nfs4_remove_state_owner_locked(sp);
 508         }
 509         spin_unlock(&clp->cl_lock);
 510
 511         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 512                 list_del(&sp->so_lru);
 513                 nfs4_free_state_owner(sp);
 514         }
 515 }
 516
 517 /**
 518  * nfs4_get_state_owner - Look up a state owner given a credential
 519  * @server: nfs_server to search
 520  * @cred: RPC credential to match
 521  *
 522  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 523  */
 524 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 525                                               struct rpc_cred *cred,
 526                                               gfp_t gfp_flags)
 527 {
 528         struct nfs_client *clp = server->nfs_client;
 529         struct nfs4_state_owner *sp, *new;
 530
 531         spin_lock(&clp->cl_lock);
 532         sp = nfs4_find_state_owner_locked(server, cred);
 533         spin_unlock(&clp->cl_lock);
 534         if (sp != NULL)
 535                 goto out;
 536         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 537         if (new == NULL)
 538                 goto out;
 539         do {
 540                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
 541                         break;
 542                 spin_lock(&clp->cl_lock);
 543                 sp = nfs4_insert_state_owner_locked(new);
 544                 spin_unlock(&clp->cl_lock);
 545         } while (sp == ERR_PTR(-EAGAIN));
 546         if (sp != new)
 547                 nfs4_free_state_owner(new);
 548 out:
 549         nfs4_gc_state_owners(server);
 550         return sp;
 551 }
 552
 553 /**
 554  * nfs4_put_state_owner - Release a nfs4_state_owner
 555  * @sp: state owner data to release
 556  */
 557 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 558 {
 559         struct nfs_server *server = sp->so_server;
 560         struct nfs_client *clp = server->nfs_client;
 561
 562         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 563                 return;
 564
 565         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
 566                 sp->so_expires = jiffies;
 567                 list_add_tail(&sp->so_lru, &server->state_owners_lru);
 568                 spin_unlock(&clp->cl_lock);
 569         } else {
 570                 nfs4_remove_state_owner_locked(sp);
 571                 spin_unlock(&clp->cl_lock);
 572                 nfs4_free_state_owner(sp);
 573         }
 574 }
 575
 576 /**
 577  * nfs4_purge_state_owners - Release all cached state owners
 578  * @server: nfs_server with cached state owners to release
 579  *
 580  * Called at umount time.  Remaining state owners will be on
 581  * the LRU with ref count of zero.
 582  */
 583 void nfs4_purge_state_owners(struct nfs_server *server)
 584 {
 585         struct nfs_client *clp = server->nfs_client;
 586         struct nfs4_state_owner *sp, *tmp;
 587         LIST_HEAD(doomed);
 588
 589         spin_lock(&clp->cl_lock);
 590         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 591                 list_move(&sp->so_lru, &doomed);
 592                 nfs4_remove_state_owner_locked(sp);
 593         }
 594         spin_unlock(&clp->cl_lock);
 595
 596         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 597                 list_del(&sp->so_lru);
 598                 nfs4_free_state_owner(sp);
 599         }
 600 }
 601
 602 static struct nfs4_state *
 603 nfs4_alloc_open_state(void)
 604 {
 605         struct nfs4_state *state;
 606
 607         state = kzalloc(sizeof(*state), GFP_NOFS);
 608         if (!state)
 609                 return NULL;
 610         atomic_set(&state->count, 1);
 611         INIT_LIST_HEAD(&state->lock_states);
 612         spin_lock_init(&state->state_lock);
 613         seqlock_init(&state->seqlock);
 614         return state;
 615 }
 616
 617 void
 618 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 619 {
 620         if (state->state == fmode)
 621                 return;
 622         /* NB! List reordering - see the reclaim code for why.  */
 623         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 624                 if (fmode & FMODE_WRITE)
 625                         list_move(&state->open_states, &state->owner->so_states);
 626                 else
 627                         list_move_tail(&state->open_states, &state->owner->so_states);
 628         }
 629         state->state = fmode;
 630 }
 631
 632 static struct nfs4_state *
 633 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 634 {
 635         struct nfs_inode *nfsi = NFS_I(inode);
 636         struct nfs4_state *state;
 637
 638         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 639                 if (state->owner != owner)
 640                         continue;
 641                 if (atomic_inc_not_zero(&state->count))
 642                         return state;
 643         }
 644         return NULL;
 645 }
 646
 647 static void
 648 nfs4_free_open_state(struct nfs4_state *state)
 649 {
 650         kfree(state);
 651 }
 652
 653 struct nfs4_state *
 654 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 655 {
 656         struct nfs4_state *state, *new;
 657         struct nfs_inode *nfsi = NFS_I(inode);
 658
 659         spin_lock(&inode->i_lock);
 660         state = __nfs4_find_state_byowner(inode, owner);
 661         spin_unlock(&inode->i_lock);
 662         if (state)
 663                 goto out;
 664         new = nfs4_alloc_open_state();
 665         spin_lock(&owner->so_lock);
 666         spin_lock(&inode->i_lock);
 667         state = __nfs4_find_state_byowner(inode, owner);
 668         if (state == NULL && new != NULL) {
 669                 state = new;
 670                 state->owner = owner;
 671                 atomic_inc(&owner->so_count);
 672                 list_add(&state->inode_states, &nfsi->open_states);
 673                 ihold(inode);
 674                 state->inode = inode;
 675                 spin_unlock(&inode->i_lock);
 676                 /* Note: The reclaim code dictates that we add stateless
 677                  * and read-only stateids to the end of the list */
 678                 list_add_tail(&state->open_states, &owner->so_states);
 679                 spin_unlock(&owner->so_lock);
 680         } else {
 681                 spin_unlock(&inode->i_lock);
 682                 spin_unlock(&owner->so_lock);
 683                 if (new)
 684                         nfs4_free_open_state(new);
 685         }
 686 out:
 687         return state;
 688 }
 689
 690 void nfs4_put_open_state(struct nfs4_state *state)
 691 {
 692         struct inode *inode = state->inode;
 693         struct nfs4_state_owner *owner = state->owner;
 694
 695         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 696                 return;
 697         spin_lock(&inode->i_lock);
 698         list_del(&state->inode_states);
 699         list_del(&state->open_states);
 700         spin_unlock(&inode->i_lock);
 701         spin_unlock(&owner->so_lock);
 702         iput(inode);
 703         nfs4_free_open_state(state);
 704         nfs4_put_state_owner(owner);
 705 }
 706
 707 /*
 708  * Close the current file.
 709  */
 710 static void __nfs4_close(struct nfs4_state *state,
 711                 fmode_t fmode, gfp_t gfp_mask, int wait)
 712 {
 713         struct nfs4_state_owner *owner = state->owner;
 714         int call_close = 0;
 715         fmode_t newstate;
 716
 717         atomic_inc(&owner->so_count);
 718         /* Protect against nfs4_find_state() */
 719         spin_lock(&owner->so_lock);
 720         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 721                 case FMODE_READ:
 722                         state->n_rdonly--;
 723                         break;
 724                 case FMODE_WRITE:
 725                         state->n_wronly--;
 726                         break;
 727                 case FMODE_READ|FMODE_WRITE:
 728                         state->n_rdwr--;
 729         }
 730         newstate = FMODE_READ|FMODE_WRITE;
 731         if (state->n_rdwr == 0) {
 732                 if (state->n_rdonly == 0) {
 733                         newstate &= ~FMODE_READ;
 734                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 735                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 736                 }
 737                 if (state->n_wronly == 0) {
 738                         newstate &= ~FMODE_WRITE;
 739                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 740                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 741                 }
 742                 if (newstate == 0)
 743                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 744         }
 745         nfs4_state_set_mode_locked(state, newstate);
 746         spin_unlock(&owner->so_lock);
 747
 748         if (!call_close) {
 749                 nfs4_put_open_state(state);
 750                 nfs4_put_state_owner(owner);
 751         } else {
 752                 bool roc = pnfs_roc(state->inode);
 753
 754                 nfs4_do_close(state, gfp_mask, wait, roc);
 755         }
 756 }
 757
 758 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 759 {
 760         __nfs4_close(state, fmode, GFP_NOFS, 0);
 761 }
 762
 763 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 764 {
 765         __nfs4_close(state, fmode, GFP_KERNEL, 1);
 766 }
 767
 768 /*
 769  * Search the state->lock_states for an existing lock_owner
 770  * that is compatible with current->files
 771  */
 772 static struct nfs4_lock_state *
 773 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 774 {
 775         struct nfs4_lock_state *pos;
 776         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 777                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
 778                         continue;
 779                 switch (pos->ls_owner.lo_type) {
 780                 case NFS4_POSIX_LOCK_TYPE:
 781                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
 782                                 continue;
 783                         break;
 784                 case NFS4_FLOCK_LOCK_TYPE:
 785                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
 786                                 continue;
 787                 }
 788                 atomic_inc(&pos->ls_count);
 789                 return pos;
 790         }
 791         return NULL;
 792 }
 793
 794 /*
 795  * Return a compatible lock_state. If no initialized lock_state structure
 796  * exists, return an uninitialized one.
 797  *
 798  */
 799 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)
 800 {
 801         struct nfs4_lock_state *lsp;
 802         struct nfs_server *server = state->owner->so_server;
 803         struct nfs_client *clp = server->nfs_client;
 804
 805         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 806         if (lsp == NULL)
 807                 return NULL;
 808         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 809         spin_lock_init(&lsp->ls_sequence.lock);
 810         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 811         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 812         atomic_set(&lsp->ls_count, 1);
 813         lsp->ls_state = state;
 814         lsp->ls_owner.lo_type = type;
 815         switch (lsp->ls_owner.lo_type) {
 816         case NFS4_FLOCK_LOCK_TYPE:
 817                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
 818                 break;
 819         case NFS4_POSIX_LOCK_TYPE:
 820                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
 821                 break;
 822         default:
 823                 kfree(lsp);
 824                 return NULL;
 825         }
 826         spin_lock(&clp->cl_lock);
 827         nfs_alloc_unique_id_locked(&server->lockowner_id, &lsp->ls_id, 1, 64);
 828         spin_unlock(&clp->cl_lock);
 829         INIT_LIST_HEAD(&lsp->ls_locks);
 830         return lsp;
 831 }
 832
 833 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 834 {
 835         struct nfs_server *server = lsp->ls_state->owner->so_server;
 836         struct nfs_client *clp = server->nfs_client;
 837
 838         spin_lock(&clp->cl_lock);
 839         nfs_free_unique_id(&server->lockowner_id, &lsp->ls_id);
 840         spin_unlock(&clp->cl_lock);
 841         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 842         kfree(lsp);
 843 }
 844
 845 /*
 846  * Return a compatible lock_state. If no initialized lock_state structure
 847  * exists, return an uninitialized one.
 848  *
 849  */
 850 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
 851 {
 852         struct nfs4_lock_state *lsp, *new = NULL;
 853
 854         for(;;) {
 855                 spin_lock(&state->state_lock);
 856                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
 857                 if (lsp != NULL)
 858                         break;
 859                 if (new != NULL) {
 860                         list_add(&new->ls_locks, &state->lock_states);
 861                         set_bit(LK_STATE_IN_USE, &state->flags);
 862                         lsp = new;
 863                         new = NULL;
 864                         break;
 865                 }
 866                 spin_unlock(&state->state_lock);
 867                 new = nfs4_alloc_lock_state(state, owner, pid, type);
 868                 if (new == NULL)
 869                         return NULL;
 870         }
 871         spin_unlock(&state->state_lock);
 872         if (new != NULL)
 873                 nfs4_free_lock_state(new);
 874         return lsp;
 875 }
 876
 877 /*
 878  * Release reference to lock_state, and free it if we see that
 879  * it is no longer in use
 880  */
 881 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 882 {
 883         struct nfs4_state *state;
 884
 885         if (lsp == NULL)
 886                 return;
 887         state = lsp->ls_state;
 888         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 889                 return;
 890         list_del(&lsp->ls_locks);
 891         if (list_empty(&state->lock_states))
 892                 clear_bit(LK_STATE_IN_USE, &state->flags);
 893         spin_unlock(&state->state_lock);
 894         if (lsp->ls_flags & NFS_LOCK_INITIALIZED)
 895                 nfs4_release_lockowner(lsp);
 896         nfs4_free_lock_state(lsp);
 897 }
 898
 899 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 900 {
 901         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 902
 903         dst->fl_u.nfs4_fl.owner = lsp;
 904         atomic_inc(&lsp->ls_count);
 905 }
 906
 907 static void nfs4_fl_release_lock(struct file_lock *fl)
 908 {
 909         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 910 }
 911
 912 static const struct file_lock_operations nfs4_fl_lock_ops = {
 913         .fl_copy_lock = nfs4_fl_copy_lock,
 914         .fl_release_private = nfs4_fl_release_lock,
 915 };
 916
 917 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 918 {
 919         struct nfs4_lock_state *lsp;
 920
 921         if (fl->fl_ops != NULL)
 922                 return 0;
 923         if (fl->fl_flags & FL_POSIX)
 924                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
 925         else if (fl->fl_flags & FL_FLOCK)
 926                 lsp = nfs4_get_lock_state(state, 0, fl->fl_pid, NFS4_FLOCK_LOCK_TYPE);
 927         else
 928                 return -EINVAL;
 929         if (lsp == NULL)
 930                 return -ENOMEM;
 931         fl->fl_u.nfs4_fl.owner = lsp;
 932         fl->fl_ops = &nfs4_fl_lock_ops;
 933         return 0;
 934 }
 935
 936 /*
 937  * Byte-range lock aware utility to initialize the stateid of read/write
 938  * requests.
 939  */
 940 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid)
 941 {
 942         struct nfs4_lock_state *lsp;
 943         int seq;
 944
 945         do {
 946                 seq = read_seqbegin(&state->seqlock);
 947                 memcpy(dst, &state->stateid, sizeof(*dst));
 948         } while (read_seqretry(&state->seqlock, seq));
 949         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 950                 return;
 951
 952         spin_lock(&state->state_lock);
 953         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
 954         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 955                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 956         spin_unlock(&state->state_lock);
 957         nfs4_put_lock_state(lsp);
 958 }
 959
 960 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
 961 {
 962         struct nfs_seqid *new;
 963
 964         new = kmalloc(sizeof(*new), gfp_mask);
 965         if (new != NULL) {
 966                 new->sequence = counter;
 967                 INIT_LIST_HEAD(&new->list);
 968         }
 969         return new;
 970 }
 971
 972 void nfs_release_seqid(struct nfs_seqid *seqid)
 973 {
 974         if (!list_empty(&seqid->list)) {
 975                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 976
 977                 spin_lock(&sequence->lock);
 978                 list_del_init(&seqid->list);
 979                 spin_unlock(&sequence->lock);
 980                 rpc_wake_up(&sequence->wait);
 981         }
 982 }
 983
 984 void nfs_free_seqid(struct nfs_seqid *seqid)
 985 {
 986         nfs_release_seqid(seqid);
 987         kfree(seqid);
 988 }
 989
 990 /*
 991  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 992  * failed with a seqid incrementing error -
 993  * see comments nfs_fs.h:seqid_mutating_error()
 994  */
 995 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 996 {
 997         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 998         switch (status) {
 999                 case 0:
1000                         break;
1001                 case -NFS4ERR_BAD_SEQID:
1002                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1003                                 return;
1004                         printk(KERN_WARNING "NFS: v4 server returned a bad"
1005                                         " sequence-id error on an"
1006                                         " unconfirmed sequence %p!\n",
1007                                         seqid->sequence);
1008                 case -NFS4ERR_STALE_CLIENTID:
1009                 case -NFS4ERR_STALE_STATEID:
1010                 case -NFS4ERR_BAD_STATEID:
1011                 case -NFS4ERR_BADXDR:
1012                 case -NFS4ERR_RESOURCE:
1013                 case -NFS4ERR_NOFILEHANDLE:
1014                         /* Non-seqid mutating errors */
1015                         return;
1016         };
1017         /*
1018          * Note: no locking needed as we are guaranteed to be first
1019          * on the sequence list
1020          */
1021         seqid->sequence->counter++;
1022 }
1023
1024 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1025 {
1026         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1027                                         struct nfs4_state_owner, so_seqid);
1028         struct nfs_server *server = sp->so_server;
1029
1030         if (status == -NFS4ERR_BAD_SEQID)
1031                 nfs4_drop_state_owner(sp);
1032         if (!nfs4_has_session(server->nfs_client))
1033                 nfs_increment_seqid(status, seqid);
1034 }
1035
1036 /*
1037  * Increment the seqid if the LOCK/LOCKU succeeded, or
1038  * failed with a seqid incrementing error -
1039  * see comments nfs_fs.h:seqid_mutating_error()
1040  */
1041 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1042 {
1043         nfs_increment_seqid(status, seqid);
1044 }
1045
1046 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1047 {
1048         struct rpc_sequence *sequence = seqid->sequence->sequence;
1049         int status = 0;
1050
1051         spin_lock(&sequence->lock);
1052         if (list_empty(&seqid->list))
1053                 list_add_tail(&seqid->list, &sequence->list);
1054         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1055                 goto unlock;
1056         rpc_sleep_on(&sequence->wait, task, NULL);
1057         status = -EAGAIN;
1058 unlock:
1059         spin_unlock(&sequence->lock);
1060         return status;
1061 }
1062
1063 static int nfs4_run_state_manager(void *);
1064
1065 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1066 {
1067         smp_mb__before_clear_bit();
1068         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1069         smp_mb__after_clear_bit();
1070         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1071         rpc_wake_up(&clp->cl_rpcwaitq);
1072 }
1073
1074 /*
1075  * Schedule the nfs_client asynchronous state management routine
1076  */
1077 void nfs4_schedule_state_manager(struct nfs_client *clp)
1078 {
1079         struct task_struct *task;
1080
1081         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1082                 return;
1083         __module_get(THIS_MODULE);
1084         atomic_inc(&clp->cl_count);
1085         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
1086                                 rpc_peeraddr2str(clp->cl_rpcclient,
1087                                                         RPC_DISPLAY_ADDR));
1088         if (!IS_ERR(task))
1089                 return;
1090         nfs4_clear_state_manager_bit(clp);
1091         nfs_put_client(clp);
1092         module_put(THIS_MODULE);
1093 }
1094
1095 /*
1096  * Schedule a lease recovery attempt
1097  */
1098 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1099 {
1100         if (!clp)
1101                 return;
1102         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1103                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1104         nfs4_schedule_state_manager(clp);
1105 }
1106
1107 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1108 {
1109         nfs_handle_cb_pathdown(clp);
1110         nfs4_schedule_state_manager(clp);
1111 }
1112
1113 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1114 {
1115
1116         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1117         /* Don't recover state that expired before the reboot */
1118         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1119                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1120                 return 0;
1121         }
1122         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1123         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1124         return 1;
1125 }
1126
1127 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1128 {
1129         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1130         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1131         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1132         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1133         return 1;
1134 }
1135
1136 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1137 {
1138         struct nfs_client *clp = server->nfs_client;
1139
1140         nfs4_state_mark_reclaim_nograce(clp, state);
1141         nfs4_schedule_state_manager(clp);
1142 }
1143
1144 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1145 {
1146         struct inode *inode = state->inode;
1147         struct nfs_inode *nfsi = NFS_I(inode);
1148         struct file_lock *fl;
1149         int status = 0;
1150
1151         if (inode->i_flock == NULL)
1152                 return 0;
1153
1154         /* Guard against delegation returns and new lock/unlock calls */
1155         down_write(&nfsi->rwsem);
1156         /* Protect inode->i_flock using the BKL */
1157         lock_flocks();
1158         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1159                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1160                         continue;
1161                 if (nfs_file_open_context(fl->fl_file)->state != state)
1162                         continue;
1163                 unlock_flocks();
1164                 status = ops->recover_lock(state, fl);
1165                 switch (status) {
1166                         case 0:
1167                                 break;
1168                         case -ESTALE:
1169                         case -NFS4ERR_ADMIN_REVOKED:
1170                         case -NFS4ERR_STALE_STATEID:
1171                         case -NFS4ERR_BAD_STATEID:
1172                         case -NFS4ERR_EXPIRED:
1173                         case -NFS4ERR_NO_GRACE:
1174                         case -NFS4ERR_STALE_CLIENTID:
1175                         case -NFS4ERR_BADSESSION:
1176                         case -NFS4ERR_BADSLOT:
1177                         case -NFS4ERR_BAD_HIGH_SLOT:
1178                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1179                                 goto out;
1180                         default:
1181                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1182                                                 __func__, status);
1183                         case -ENOMEM:
1184                         case -NFS4ERR_DENIED:
1185                         case -NFS4ERR_RECLAIM_BAD:
1186                         case -NFS4ERR_RECLAIM_CONFLICT:
1187                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1188                                 status = 0;
1189                 }
1190                 lock_flocks();
1191         }
1192         unlock_flocks();
1193 out:
1194         up_write(&nfsi->rwsem);
1195         return status;
1196 }
1197
1198 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1199 {
1200         struct nfs4_state *state;
1201         struct nfs4_lock_state *lock;
1202         int status = 0;
1203
1204         /* Note: we rely on the sp->so_states list being ordered
1205          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1206          * states first.
1207          * This is needed to ensure that the server won't give us any
1208          * read delegations that we have to return if, say, we are
1209          * recovering after a network partition or a reboot from a
1210          * server that doesn't support a grace period.
1211          */
1212 restart:
1213         spin_lock(&sp->so_lock);
1214         list_for_each_entry(state, &sp->so_states, open_states) {
1215                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1216                         continue;
1217                 if (state->state == 0)
1218                         continue;
1219                 atomic_inc(&state->count);
1220                 spin_unlock(&sp->so_lock);
1221                 status = ops->recover_open(sp, state);
1222                 if (status >= 0) {
1223                         status = nfs4_reclaim_locks(state, ops);
1224                         if (status >= 0) {
1225                                 spin_lock(&state->state_lock);
1226                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1227                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1228                                                 printk("%s: Lock reclaim failed!\n",
1229                                                         __func__);
1230                                 }
1231                                 spin_unlock(&state->state_lock);
1232                                 nfs4_put_open_state(state);
1233                                 goto restart;
1234                         }
1235                 }
1236                 switch (status) {
1237                         default:
1238                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1239                                                 __func__, status);
1240                         case -ENOENT:
1241                         case -ENOMEM:
1242                         case -ESTALE:
1243                                 /*
1244                                  * Open state on this file cannot be recovered
1245                                  * All we can do is revert to using the zero stateid.
1246                                  */
1247                                 memset(state->stateid.data, 0,
1248                                         sizeof(state->stateid.data));
1249                                 /* Mark the file as being 'closed' */
1250                                 state->state = 0;
1251                                 break;
1252                         case -EKEYEXPIRED:
1253                                 /*
1254                                  * User RPCSEC_GSS context has expired.
1255                                  * We cannot recover this stateid now, so
1256                                  * skip it and allow recovery thread to
1257                                  * proceed.
1258                                  */
1259                                 break;
1260                         case -NFS4ERR_ADMIN_REVOKED:
1261                         case -NFS4ERR_STALE_STATEID:
1262                         case -NFS4ERR_BAD_STATEID:
1263                         case -NFS4ERR_RECLAIM_BAD:
1264                         case -NFS4ERR_RECLAIM_CONFLICT:
1265                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1266                                 break;
1267                         case -NFS4ERR_EXPIRED:
1268                         case -NFS4ERR_NO_GRACE:
1269                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1270                         case -NFS4ERR_STALE_CLIENTID:
1271                         case -NFS4ERR_BADSESSION:
1272                         case -NFS4ERR_BADSLOT:
1273                         case -NFS4ERR_BAD_HIGH_SLOT:
1274                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1275                                 goto out_err;
1276                 }
1277                 nfs4_put_open_state(state);
1278                 goto restart;
1279         }
1280         spin_unlock(&sp->so_lock);
1281         return 0;
1282 out_err:
1283         nfs4_put_open_state(state);
1284         return status;
1285 }
1286
1287 static void nfs4_clear_open_state(struct nfs4_state *state)
1288 {
1289         struct nfs4_lock_state *lock;
1290
1291         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1292         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1293         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1294         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1295         spin_lock(&state->state_lock);
1296         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1297                 lock->ls_seqid.flags = 0;
1298                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1299         }
1300         spin_unlock(&state->state_lock);
1301 }
1302
1303 static void nfs4_reset_seqids(struct nfs_server *server,
1304         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1305 {
1306         struct nfs_client *clp = server->nfs_client;
1307         struct nfs4_state_owner *sp;
1308         struct rb_node *pos;
1309         struct nfs4_state *state;
1310
1311         spin_lock(&clp->cl_lock);
1312         for (pos = rb_first(&server->state_owners);
1313              pos != NULL;
1314              pos = rb_next(pos)) {
1315                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1316                 sp->so_seqid.flags = 0;
1317                 spin_lock(&sp->so_lock);
1318                 list_for_each_entry(state, &sp->so_states, open_states) {
1319                         if (mark_reclaim(clp, state))
1320                                 nfs4_clear_open_state(state);
1321                 }
1322                 spin_unlock(&sp->so_lock);
1323         }
1324         spin_unlock(&clp->cl_lock);
1325 }
1326
1327 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1328         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1329 {
1330         struct nfs_server *server;
1331
1332         rcu_read_lock();
1333         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1334                 nfs4_reset_seqids(server, mark_reclaim);
1335         rcu_read_unlock();
1336 }
1337
1338 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1339 {
1340         /* Mark all delegations for reclaim */
1341         nfs_delegation_mark_reclaim(clp);
1342         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1343 }
1344
1345 static void nfs4_reclaim_complete(struct nfs_client *clp,
1346                                  const struct nfs4_state_recovery_ops *ops)
1347 {
1348         /* Notify the server we're done reclaiming our state */
1349         if (ops->reclaim_complete)
1350                 (void)ops->reclaim_complete(clp);
1351 }
1352
1353 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1354 {
1355         struct nfs_client *clp = server->nfs_client;
1356         struct nfs4_state_owner *sp;
1357         struct rb_node *pos;
1358         struct nfs4_state *state;
1359
1360         spin_lock(&clp->cl_lock);
1361         for (pos = rb_first(&server->state_owners);
1362              pos != NULL;
1363              pos = rb_next(pos)) {
1364                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1365                 spin_lock(&sp->so_lock);
1366                 list_for_each_entry(state, &sp->so_states, open_states) {
1367                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1368                                                 &state->flags))
1369                                 continue;
1370                         nfs4_state_mark_reclaim_nograce(clp, state);
1371                 }
1372                 spin_unlock(&sp->so_lock);
1373         }
1374         spin_unlock(&clp->cl_lock);
1375 }
1376
1377 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1378 {
1379         struct nfs_server *server;
1380
1381         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1382                 return 0;
1383
1384         rcu_read_lock();
1385         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1386                 nfs4_clear_reclaim_server(server);
1387         rcu_read_unlock();
1388
1389         nfs_delegation_reap_unclaimed(clp);
1390         return 1;
1391 }
1392
1393 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1394 {
1395         if (!nfs4_state_clear_reclaim_reboot(clp))
1396                 return;
1397         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1398 }
1399
1400 static void nfs_delegation_clear_all(struct nfs_client *clp)
1401 {
1402         nfs_delegation_mark_reclaim(clp);
1403         nfs_delegation_reap_unclaimed(clp);
1404 }
1405
1406 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1407 {
1408         nfs_delegation_clear_all(clp);
1409         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1410 }
1411
1412 static void nfs4_warn_keyexpired(const char *s)
1413 {
1414         printk_ratelimited(KERN_WARNING "Error: state manager"
1415                         " encountered RPCSEC_GSS session"
1416                         " expired against NFSv4 server %s.\n",
1417                         s);
1418 }
1419
1420 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1421 {
1422         switch (error) {
1423                 case 0:
1424                         break;
1425                 case -NFS4ERR_CB_PATH_DOWN:
1426                         nfs_handle_cb_pathdown(clp);
1427                         break;
1428                 case -NFS4ERR_NO_GRACE:
1429                         nfs4_state_end_reclaim_reboot(clp);
1430                         break;
1431                 case -NFS4ERR_STALE_CLIENTID:
1432                 case -NFS4ERR_LEASE_MOVED:
1433                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1434                         nfs4_state_clear_reclaim_reboot(clp);
1435                         nfs4_state_start_reclaim_reboot(clp);
1436                         break;
1437                 case -NFS4ERR_EXPIRED:
1438                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1439                         nfs4_state_start_reclaim_nograce(clp);
1440                         break;
1441                 case -NFS4ERR_BADSESSION:
1442                 case -NFS4ERR_BADSLOT:
1443                 case -NFS4ERR_BAD_HIGH_SLOT:
1444                 case -NFS4ERR_DEADSESSION:
1445                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1446                 case -NFS4ERR_SEQ_FALSE_RETRY:
1447                 case -NFS4ERR_SEQ_MISORDERED:
1448                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1449                         /* Zero session reset errors */
1450                         break;
1451                 case -EKEYEXPIRED:
1452                         /* Nothing we can do */
1453                         nfs4_warn_keyexpired(clp->cl_hostname);
1454                         break;
1455                 default:
1456                         return error;
1457         }
1458         return 0;
1459 }
1460
1461 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1462 {
1463         struct nfs4_state_owner *sp;
1464         struct nfs_server *server;
1465         struct rb_node *pos;
1466         int status = 0;
1467
1468 restart:
1469         rcu_read_lock();
1470         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1471                 nfs4_purge_state_owners(server);
1472                 spin_lock(&clp->cl_lock);
1473                 for (pos = rb_first(&server->state_owners);
1474                      pos != NULL;
1475                      pos = rb_next(pos)) {
1476                         sp = rb_entry(pos,
1477                                 struct nfs4_state_owner, so_server_node);
1478                         if (!test_and_clear_bit(ops->owner_flag_bit,
1479                                                         &sp->so_flags))
1480                                 continue;
1481                         atomic_inc(&sp->so_count);
1482                         spin_unlock(&clp->cl_lock);
1483                         rcu_read_unlock();
1484
1485                         status = nfs4_reclaim_open_state(sp, ops);
1486                         if (status < 0) {
1487                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1488                                 nfs4_put_state_owner(sp);
1489                                 return nfs4_recovery_handle_error(clp, status);
1490                         }
1491
1492                         nfs4_put_state_owner(sp);
1493                         goto restart;
1494                 }
1495                 spin_unlock(&clp->cl_lock);
1496         }
1497         rcu_read_unlock();
1498         return status;
1499 }
1500
1501 static int nfs4_check_lease(struct nfs_client *clp)
1502 {
1503         struct rpc_cred *cred;
1504         const struct nfs4_state_maintenance_ops *ops =
1505                 clp->cl_mvops->state_renewal_ops;
1506         int status;
1507
1508         /* Is the client already known to have an expired lease? */
1509         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1510                 return 0;
1511         spin_lock(&clp->cl_lock);
1512         cred = ops->get_state_renewal_cred_locked(clp);
1513         spin_unlock(&clp->cl_lock);
1514         if (cred == NULL) {
1515                 cred = nfs4_get_setclientid_cred(clp);
1516                 status = -ENOKEY;
1517                 if (cred == NULL)
1518                         goto out;
1519         }
1520         status = ops->renew_lease(clp, cred);
1521         put_rpccred(cred);
1522 out:
1523         return nfs4_recovery_handle_error(clp, status);
1524 }
1525
1526 static int nfs4_reclaim_lease(struct nfs_client *clp)
1527 {
1528         struct rpc_cred *cred;
1529         const struct nfs4_state_recovery_ops *ops =
1530                 clp->cl_mvops->reboot_recovery_ops;
1531         int status = -ENOENT;
1532
1533         cred = ops->get_clid_cred(clp);
1534         if (cred != NULL) {
1535                 status = ops->establish_clid(clp, cred);
1536                 put_rpccred(cred);
1537                 /* Handle case where the user hasn't set up machine creds */
1538                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1539                         nfs4_clear_machine_cred(clp);
1540                         status = -EAGAIN;
1541                 }
1542                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1543                         status = -EPROTONOSUPPORT;
1544         }
1545         return status;
1546 }
1547
1548 #ifdef CONFIG_NFS_V4_1
1549 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1550 {
1551         struct nfs_client *clp = session->clp;
1552
1553         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1554         nfs4_schedule_lease_recovery(clp);
1555 }
1556 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1557
1558 void nfs41_handle_recall_slot(struct nfs_client *clp)
1559 {
1560         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1561         nfs4_schedule_state_manager(clp);
1562 }
1563
1564 static void nfs4_reset_all_state(struct nfs_client *clp)
1565 {
1566         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1567                 clp->cl_boot_time = CURRENT_TIME;
1568                 nfs4_state_start_reclaim_nograce(clp);
1569                 nfs4_schedule_state_manager(clp);
1570         }
1571 }
1572
1573 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1574 {
1575         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1576                 nfs4_state_start_reclaim_reboot(clp);
1577                 nfs4_schedule_state_manager(clp);
1578         }
1579 }
1580
1581 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1582 {
1583         /* Temporary */
1584         nfs4_reset_all_state(clp);
1585 }
1586
1587 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1588 {
1589         /* This will need to handle layouts too */
1590         nfs_expire_all_delegations(clp);
1591 }
1592
1593 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1594 {
1595         nfs_expire_all_delegations(clp);
1596         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1597                 nfs4_schedule_state_manager(clp);
1598 }
1599
1600 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1601 {
1602         if (!flags)
1603                 return;
1604         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1605                 nfs41_handle_server_reboot(clp);
1606         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1607                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1608                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1609                             SEQ4_STATUS_LEASE_MOVED))
1610                 nfs41_handle_state_revoked(clp);
1611         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1612                 nfs41_handle_recallable_state_revoked(clp);
1613         if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1614                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1615                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1616                 nfs41_handle_cb_path_down(clp);
1617 }
1618
1619 static int nfs4_reset_session(struct nfs_client *clp)
1620 {
1621         int status;
1622
1623         nfs4_begin_drain_session(clp);
1624         status = nfs4_proc_destroy_session(clp->cl_session);
1625         if (status && status != -NFS4ERR_BADSESSION &&
1626             status != -NFS4ERR_DEADSESSION) {
1627                 status = nfs4_recovery_handle_error(clp, status);
1628                 goto out;
1629         }
1630
1631         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1632         status = nfs4_proc_create_session(clp);
1633         if (status) {
1634                 status = nfs4_recovery_handle_error(clp, status);
1635                 goto out;
1636         }
1637         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1638         /* create_session negotiated new slot table */
1639         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1640
1641          /* Let the state manager reestablish state */
1642         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1643                 nfs41_setup_state_renewal(clp);
1644 out:
1645         return status;
1646 }
1647
1648 static int nfs4_recall_slot(struct nfs_client *clp)
1649 {
1650         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1651         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1652         struct nfs4_slot *new, *old;
1653         int i;
1654
1655         nfs4_begin_drain_session(clp);
1656         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1657                       GFP_NOFS);
1658         if (!new)
1659                 return -ENOMEM;
1660
1661         spin_lock(&fc_tbl->slot_tbl_lock);
1662         for (i = 0; i < fc_tbl->target_max_slots; i++)
1663                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1664         old = fc_tbl->slots;
1665         fc_tbl->slots = new;
1666         fc_tbl->max_slots = fc_tbl->target_max_slots;
1667         fc_tbl->target_max_slots = 0;
1668         fc_attrs->max_reqs = fc_tbl->max_slots;
1669         spin_unlock(&fc_tbl->slot_tbl_lock);
1670
1671         kfree(old);
1672         nfs4_end_drain_session(clp);
1673         return 0;
1674 }
1675
1676 #else /* CONFIG_NFS_V4_1 */
1677 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1678 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1679 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1680 #endif /* CONFIG_NFS_V4_1 */
1681
1682 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1683  * on EXCHANGE_ID for v4.1
1684  */
1685 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1686 {
1687         switch (status) {
1688         case -NFS4ERR_CLID_INUSE:
1689         case -NFS4ERR_STALE_CLIENTID:
1690                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1691                 break;
1692         case -NFS4ERR_DELAY:
1693         case -ETIMEDOUT:
1694         case -EAGAIN:
1695                 ssleep(1);
1696                 break;
1697
1698         case -EKEYEXPIRED:
1699                 nfs4_warn_keyexpired(clp->cl_hostname);
1700         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1701                                  * in nfs4_exchange_id */
1702         default:
1703                 return;
1704         }
1705         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1706 }
1707
1708 static void nfs4_state_manager(struct nfs_client *clp)
1709 {
1710         int status = 0;
1711
1712         /* Ensure exclusive access to NFSv4 state */
1713         do {
1714                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1715                         /* We're going to have to re-establish a clientid */
1716                         status = nfs4_reclaim_lease(clp);
1717                         if (status) {
1718                                 nfs4_set_lease_expired(clp, status);
1719                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1720                                                         &clp->cl_state))
1721                                         continue;
1722                                 if (clp->cl_cons_state ==
1723                                                         NFS_CS_SESSION_INITING)
1724                                         nfs_mark_client_ready(clp, status);
1725                                 goto out_error;
1726                         }
1727                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1728
1729                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1730                                                &clp->cl_state))
1731                                 nfs4_state_start_reclaim_nograce(clp);
1732                         else
1733                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1734                                         &clp->cl_state);
1735
1736                         pnfs_destroy_all_layouts(clp);
1737                 }
1738
1739                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1740                         status = nfs4_check_lease(clp);
1741                         if (status < 0)
1742                                 goto out_error;
1743                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1744                                 continue;
1745                 }
1746
1747                 /* Initialize or reset the session */
1748                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1749                    && nfs4_has_session(clp)) {
1750                         status = nfs4_reset_session(clp);
1751                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1752                                 continue;
1753                         if (status < 0)
1754                                 goto out_error;
1755                 }
1756
1757                 /* First recover reboot state... */
1758                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1759                         status = nfs4_do_reclaim(clp,
1760                                 clp->cl_mvops->reboot_recovery_ops);
1761                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1762                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1763                                 continue;
1764                         nfs4_state_end_reclaim_reboot(clp);
1765                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1766                                 continue;
1767                         if (status < 0)
1768                                 goto out_error;
1769                 }
1770
1771                 /* Now recover expired state... */
1772                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1773                         status = nfs4_do_reclaim(clp,
1774                                 clp->cl_mvops->nograce_recovery_ops);
1775                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1776                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1777                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1778                                 continue;
1779                         if (status < 0)
1780                                 goto out_error;
1781                 }
1782
1783                 nfs4_end_drain_session(clp);
1784                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1785                         nfs_client_return_marked_delegations(clp);
1786                         continue;
1787                 }
1788                 /* Recall session slots */
1789                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1790                    && nfs4_has_session(clp)) {
1791                         status = nfs4_recall_slot(clp);
1792                         if (status < 0)
1793                                 goto out_error;
1794                         continue;
1795                 }
1796
1797
1798                 nfs4_clear_state_manager_bit(clp);
1799                 /* Did we race with an attempt to give us more work? */
1800                 if (clp->cl_state == 0)
1801                         break;
1802                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1803                         break;
1804         } while (atomic_read(&clp->cl_count) > 1);
1805         return;
1806 out_error:
1807         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1808                         " with error %d\n", clp->cl_hostname, -status);
1809         nfs4_end_drain_session(clp);
1810         nfs4_clear_state_manager_bit(clp);
1811 }
1812
1813 static int nfs4_run_state_manager(void *ptr)
1814 {
1815         struct nfs_client *clp = ptr;
1816
1817         allow_signal(SIGKILL);
1818         nfs4_state_manager(clp);
1819         nfs_put_client(clp);
1820         module_put_and_exit(0);
1821         return 0;
1822 }
1823
1824 /*
1825  * Local variables:
1826  *  c-basic-offset: 8
1827  * End:
1828  */