git.oblomov.eu Git - linux-2.6/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/smp_lock.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/workqueue.h>
  50 #include <linux/bitops.h>
  51
  52 #include "nfs4_fs.h"
  53 #include "callback.h"
  54 #include "delegation.h"
  55 #include "internal.h"
  56
  57 #define OPENOWNER_POOL_SIZE     8
  58
  59 const nfs4_stateid zero_stateid;
  60
  61 static LIST_HEAD(nfs4_clientid_list);
  62
  63 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  64 {
  65         unsigned short port;
  66         int status;
  67
  68         port = nfs_callback_tcpport;
  69         if (clp->cl_addr.ss_family == AF_INET6)
  70                 port = nfs_callback_tcpport6;
  71
  72         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred);
  73         if (status == 0)
  74                 status = nfs4_proc_setclientid_confirm(clp, cred);
  75         if (status == 0)
  76                 nfs4_schedule_state_renewal(clp);
  77         return status;
  78 }
  79
  80 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
  81 {
  82         struct rpc_cred *cred = NULL;
  83
  84         if (clp->cl_machine_cred != NULL)
  85                 cred = get_rpccred(clp->cl_machine_cred);
  86         return cred;
  87 }
  88
  89 static void nfs4_clear_machine_cred(struct nfs_client *clp)
  90 {
  91         struct rpc_cred *cred;
  92
  93         spin_lock(&clp->cl_lock);
  94         cred = clp->cl_machine_cred;
  95         clp->cl_machine_cred = NULL;
  96         spin_unlock(&clp->cl_lock);
  97         if (cred != NULL)
  98                 put_rpccred(cred);
  99 }
 100
 101 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 102 {
 103         struct nfs4_state_owner *sp;
 104         struct rb_node *pos;
 105         struct rpc_cred *cred = NULL;
 106
 107         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
 108                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 109                 if (list_empty(&sp->so_states))
 110                         continue;
 111                 cred = get_rpccred(sp->so_cred);
 112                 break;
 113         }
 114         return cred;
 115 }
 116
 117 #if defined(CONFIG_NFS_V4_1)
 118
 119 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 120 {
 121         struct rpc_cred *cred;
 122
 123         spin_lock(&clp->cl_lock);
 124         cred = nfs4_get_machine_cred_locked(clp);
 125         spin_unlock(&clp->cl_lock);
 126         return cred;
 127 }
 128
 129 #endif /* CONFIG_NFS_V4_1 */
 130
 131 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 132 {
 133         struct nfs4_state_owner *sp;
 134         struct rb_node *pos;
 135         struct rpc_cred *cred;
 136
 137         spin_lock(&clp->cl_lock);
 138         cred = nfs4_get_machine_cred_locked(clp);
 139         if (cred != NULL)
 140                 goto out;
 141         pos = rb_first(&clp->cl_state_owners);
 142         if (pos != NULL) {
 143                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 144                 cred = get_rpccred(sp->so_cred);
 145         }
 146 out:
 147         spin_unlock(&clp->cl_lock);
 148         return cred;
 149 }
 150
 151 static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
 152                 __u64 minval, int maxbits)
 153 {
 154         struct rb_node **p, *parent;
 155         struct nfs_unique_id *pos;
 156         __u64 mask = ~0ULL;
 157
 158         if (maxbits < 64)
 159                 mask = (1ULL << maxbits) - 1ULL;
 160
 161         /* Ensure distribution is more or less flat */
 162         get_random_bytes(&new->id, sizeof(new->id));
 163         new->id &= mask;
 164         if (new->id < minval)
 165                 new->id += minval;
 166 retry:
 167         p = &root->rb_node;
 168         parent = NULL;
 169
 170         while (*p != NULL) {
 171                 parent = *p;
 172                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 173
 174                 if (new->id < pos->id)
 175                         p = &(*p)->rb_left;
 176                 else if (new->id > pos->id)
 177                         p = &(*p)->rb_right;
 178                 else
 179                         goto id_exists;
 180         }
 181         rb_link_node(&new->rb_node, parent, p);
 182         rb_insert_color(&new->rb_node, root);
 183         return;
 184 id_exists:
 185         for (;;) {
 186                 new->id++;
 187                 if (new->id < minval || (new->id & mask) != new->id) {
 188                         new->id = minval;
 189                         break;
 190                 }
 191                 parent = rb_next(parent);
 192                 if (parent == NULL)
 193                         break;
 194                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 195                 if (new->id < pos->id)
 196                         break;
 197         }
 198         goto retry;
 199 }
 200
 201 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
 202 {
 203         rb_erase(&id->rb_node, root);
 204 }
 205
 206 static struct nfs4_state_owner *
 207 nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 208 {
 209         struct nfs_client *clp = server->nfs_client;
 210         struct rb_node **p = &clp->cl_state_owners.rb_node,
 211                        *parent = NULL;
 212         struct nfs4_state_owner *sp, *res = NULL;
 213
 214         while (*p != NULL) {
 215                 parent = *p;
 216                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 217
 218                 if (server < sp->so_server) {
 219                         p = &parent->rb_left;
 220                         continue;
 221                 }
 222                 if (server > sp->so_server) {
 223                         p = &parent->rb_right;
 224                         continue;
 225                 }
 226                 if (cred < sp->so_cred)
 227                         p = &parent->rb_left;
 228                 else if (cred > sp->so_cred)
 229                         p = &parent->rb_right;
 230                 else {
 231                         atomic_inc(&sp->so_count);
 232                         res = sp;
 233                         break;
 234                 }
 235         }
 236         return res;
 237 }
 238
 239 static struct nfs4_state_owner *
 240 nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
 241 {
 242         struct rb_node **p = &clp->cl_state_owners.rb_node,
 243                        *parent = NULL;
 244         struct nfs4_state_owner *sp;
 245
 246         while (*p != NULL) {
 247                 parent = *p;
 248                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 249
 250                 if (new->so_server < sp->so_server) {
 251                         p = &parent->rb_left;
 252                         continue;
 253                 }
 254                 if (new->so_server > sp->so_server) {
 255                         p = &parent->rb_right;
 256                         continue;
 257                 }
 258                 if (new->so_cred < sp->so_cred)
 259                         p = &parent->rb_left;
 260                 else if (new->so_cred > sp->so_cred)
 261                         p = &parent->rb_right;
 262                 else {
 263                         atomic_inc(&sp->so_count);
 264                         return sp;
 265                 }
 266         }
 267         nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
 268         rb_link_node(&new->so_client_node, parent, p);
 269         rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
 270         return new;
 271 }
 272
 273 static void
 274 nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
 275 {
 276         if (!RB_EMPTY_NODE(&sp->so_client_node))
 277                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 278         nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
 279 }
 280
 281 /*
 282  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 283  * create a new state_owner.
 284  *
 285  */
 286 static struct nfs4_state_owner *
 287 nfs4_alloc_state_owner(void)
 288 {
 289         struct nfs4_state_owner *sp;
 290
 291         sp = kzalloc(sizeof(*sp),GFP_KERNEL);
 292         if (!sp)
 293                 return NULL;
 294         spin_lock_init(&sp->so_lock);
 295         INIT_LIST_HEAD(&sp->so_states);
 296         INIT_LIST_HEAD(&sp->so_delegations);
 297         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 298         sp->so_seqid.sequence = &sp->so_sequence;
 299         spin_lock_init(&sp->so_sequence.lock);
 300         INIT_LIST_HEAD(&sp->so_sequence.list);
 301         atomic_set(&sp->so_count, 1);
 302         return sp;
 303 }
 304
 305 static void
 306 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 307 {
 308         if (!RB_EMPTY_NODE(&sp->so_client_node)) {
 309                 struct nfs_client *clp = sp->so_client;
 310
 311                 spin_lock(&clp->cl_lock);
 312                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 313                 RB_CLEAR_NODE(&sp->so_client_node);
 314                 spin_unlock(&clp->cl_lock);
 315         }
 316 }
 317
 318 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 319 {
 320         struct nfs_client *clp = server->nfs_client;
 321         struct nfs4_state_owner *sp, *new;
 322
 323         spin_lock(&clp->cl_lock);
 324         sp = nfs4_find_state_owner(server, cred);
 325         spin_unlock(&clp->cl_lock);
 326         if (sp != NULL)
 327                 return sp;
 328         new = nfs4_alloc_state_owner();
 329         if (new == NULL)
 330                 return NULL;
 331         new->so_client = clp;
 332         new->so_server = server;
 333         new->so_cred = cred;
 334         spin_lock(&clp->cl_lock);
 335         sp = nfs4_insert_state_owner(clp, new);
 336         spin_unlock(&clp->cl_lock);
 337         if (sp == new)
 338                 get_rpccred(cred);
 339         else {
 340                 rpc_destroy_wait_queue(&new->so_sequence.wait);
 341                 kfree(new);
 342         }
 343         return sp;
 344 }
 345
 346 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 347 {
 348         struct nfs_client *clp = sp->so_client;
 349         struct rpc_cred *cred = sp->so_cred;
 350
 351         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 352                 return;
 353         nfs4_remove_state_owner(clp, sp);
 354         spin_unlock(&clp->cl_lock);
 355         rpc_destroy_wait_queue(&sp->so_sequence.wait);
 356         put_rpccred(cred);
 357         kfree(sp);
 358 }
 359
 360 static struct nfs4_state *
 361 nfs4_alloc_open_state(void)
 362 {
 363         struct nfs4_state *state;
 364
 365         state = kzalloc(sizeof(*state), GFP_KERNEL);
 366         if (!state)
 367                 return NULL;
 368         atomic_set(&state->count, 1);
 369         INIT_LIST_HEAD(&state->lock_states);
 370         spin_lock_init(&state->state_lock);
 371         seqlock_init(&state->seqlock);
 372         return state;
 373 }
 374
 375 void
 376 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 377 {
 378         if (state->state == fmode)
 379                 return;
 380         /* NB! List reordering - see the reclaim code for why.  */
 381         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 382                 if (fmode & FMODE_WRITE)
 383                         list_move(&state->open_states, &state->owner->so_states);
 384                 else
 385                         list_move_tail(&state->open_states, &state->owner->so_states);
 386         }
 387         state->state = fmode;
 388 }
 389
 390 static struct nfs4_state *
 391 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 392 {
 393         struct nfs_inode *nfsi = NFS_I(inode);
 394         struct nfs4_state *state;
 395
 396         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 397                 if (state->owner != owner)
 398                         continue;
 399                 if (atomic_inc_not_zero(&state->count))
 400                         return state;
 401         }
 402         return NULL;
 403 }
 404
 405 static void
 406 nfs4_free_open_state(struct nfs4_state *state)
 407 {
 408         kfree(state);
 409 }
 410
 411 struct nfs4_state *
 412 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 413 {
 414         struct nfs4_state *state, *new;
 415         struct nfs_inode *nfsi = NFS_I(inode);
 416
 417         spin_lock(&inode->i_lock);
 418         state = __nfs4_find_state_byowner(inode, owner);
 419         spin_unlock(&inode->i_lock);
 420         if (state)
 421                 goto out;
 422         new = nfs4_alloc_open_state();
 423         spin_lock(&owner->so_lock);
 424         spin_lock(&inode->i_lock);
 425         state = __nfs4_find_state_byowner(inode, owner);
 426         if (state == NULL && new != NULL) {
 427                 state = new;
 428                 state->owner = owner;
 429                 atomic_inc(&owner->so_count);
 430                 list_add(&state->inode_states, &nfsi->open_states);
 431                 state->inode = igrab(inode);
 432                 spin_unlock(&inode->i_lock);
 433                 /* Note: The reclaim code dictates that we add stateless
 434                  * and read-only stateids to the end of the list */
 435                 list_add_tail(&state->open_states, &owner->so_states);
 436                 spin_unlock(&owner->so_lock);
 437         } else {
 438                 spin_unlock(&inode->i_lock);
 439                 spin_unlock(&owner->so_lock);
 440                 if (new)
 441                         nfs4_free_open_state(new);
 442         }
 443 out:
 444         return state;
 445 }
 446
 447 void nfs4_put_open_state(struct nfs4_state *state)
 448 {
 449         struct inode *inode = state->inode;
 450         struct nfs4_state_owner *owner = state->owner;
 451
 452         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 453                 return;
 454         spin_lock(&inode->i_lock);
 455         list_del(&state->inode_states);
 456         list_del(&state->open_states);
 457         spin_unlock(&inode->i_lock);
 458         spin_unlock(&owner->so_lock);
 459         iput(inode);
 460         nfs4_free_open_state(state);
 461         nfs4_put_state_owner(owner);
 462 }
 463
 464 /*
 465  * Close the current file.
 466  */
 467 static void __nfs4_close(struct path *path, struct nfs4_state *state, fmode_t fmode, int wait)
 468 {
 469         struct nfs4_state_owner *owner = state->owner;
 470         int call_close = 0;
 471         fmode_t newstate;
 472
 473         atomic_inc(&owner->so_count);
 474         /* Protect against nfs4_find_state() */
 475         spin_lock(&owner->so_lock);
 476         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 477                 case FMODE_READ:
 478                         state->n_rdonly--;
 479                         break;
 480                 case FMODE_WRITE:
 481                         state->n_wronly--;
 482                         break;
 483                 case FMODE_READ|FMODE_WRITE:
 484                         state->n_rdwr--;
 485         }
 486         newstate = FMODE_READ|FMODE_WRITE;
 487         if (state->n_rdwr == 0) {
 488                 if (state->n_rdonly == 0) {
 489                         newstate &= ~FMODE_READ;
 490                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 491                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 492                 }
 493                 if (state->n_wronly == 0) {
 494                         newstate &= ~FMODE_WRITE;
 495                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 496                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 497                 }
 498                 if (newstate == 0)
 499                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 500         }
 501         nfs4_state_set_mode_locked(state, newstate);
 502         spin_unlock(&owner->so_lock);
 503
 504         if (!call_close) {
 505                 nfs4_put_open_state(state);
 506                 nfs4_put_state_owner(owner);
 507         } else
 508                 nfs4_do_close(path, state, wait);
 509 }
 510
 511 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
 512 {
 513         __nfs4_close(path, state, fmode, 0);
 514 }
 515
 516 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
 517 {
 518         __nfs4_close(path, state, fmode, 1);
 519 }
 520
 521 /*
 522  * Search the state->lock_states for an existing lock_owner
 523  * that is compatible with current->files
 524  */
 525 static struct nfs4_lock_state *
 526 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 527 {
 528         struct nfs4_lock_state *pos;
 529         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 530                 if (pos->ls_owner != fl_owner)
 531                         continue;
 532                 atomic_inc(&pos->ls_count);
 533                 return pos;
 534         }
 535         return NULL;
 536 }
 537
 538 /*
 539  * Return a compatible lock_state. If no initialized lock_state structure
 540  * exists, return an uninitialized one.
 541  *
 542  */
 543 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 544 {
 545         struct nfs4_lock_state *lsp;
 546         struct nfs_client *clp = state->owner->so_client;
 547
 548         lsp = kzalloc(sizeof(*lsp), GFP_KERNEL);
 549         if (lsp == NULL)
 550                 return NULL;
 551         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 552         spin_lock_init(&lsp->ls_sequence.lock);
 553         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 554         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 555         atomic_set(&lsp->ls_count, 1);
 556         lsp->ls_state = state;
 557         lsp->ls_owner = fl_owner;
 558         spin_lock(&clp->cl_lock);
 559         nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
 560         spin_unlock(&clp->cl_lock);
 561         INIT_LIST_HEAD(&lsp->ls_locks);
 562         return lsp;
 563 }
 564
 565 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 566 {
 567         struct nfs_client *clp = lsp->ls_state->owner->so_client;
 568
 569         spin_lock(&clp->cl_lock);
 570         nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
 571         spin_unlock(&clp->cl_lock);
 572         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 573         kfree(lsp);
 574 }
 575
 576 /*
 577  * Return a compatible lock_state. If no initialized lock_state structure
 578  * exists, return an uninitialized one.
 579  *
 580  */
 581 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 582 {
 583         struct nfs4_lock_state *lsp, *new = NULL;
 584
 585         for(;;) {
 586                 spin_lock(&state->state_lock);
 587                 lsp = __nfs4_find_lock_state(state, owner);
 588                 if (lsp != NULL)
 589                         break;
 590                 if (new != NULL) {
 591                         list_add(&new->ls_locks, &state->lock_states);
 592                         set_bit(LK_STATE_IN_USE, &state->flags);
 593                         lsp = new;
 594                         new = NULL;
 595                         break;
 596                 }
 597                 spin_unlock(&state->state_lock);
 598                 new = nfs4_alloc_lock_state(state, owner);
 599                 if (new == NULL)
 600                         return NULL;
 601         }
 602         spin_unlock(&state->state_lock);
 603         if (new != NULL)
 604                 nfs4_free_lock_state(new);
 605         return lsp;
 606 }
 607
 608 /*
 609  * Release reference to lock_state, and free it if we see that
 610  * it is no longer in use
 611  */
 612 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 613 {
 614         struct nfs4_state *state;
 615
 616         if (lsp == NULL)
 617                 return;
 618         state = lsp->ls_state;
 619         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 620                 return;
 621         list_del(&lsp->ls_locks);
 622         if (list_empty(&state->lock_states))
 623                 clear_bit(LK_STATE_IN_USE, &state->flags);
 624         spin_unlock(&state->state_lock);
 625         nfs4_free_lock_state(lsp);
 626 }
 627
 628 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 629 {
 630         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 631
 632         dst->fl_u.nfs4_fl.owner = lsp;
 633         atomic_inc(&lsp->ls_count);
 634 }
 635
 636 static void nfs4_fl_release_lock(struct file_lock *fl)
 637 {
 638         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 639 }
 640
 641 static struct file_lock_operations nfs4_fl_lock_ops = {
 642         .fl_copy_lock = nfs4_fl_copy_lock,
 643         .fl_release_private = nfs4_fl_release_lock,
 644 };
 645
 646 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 647 {
 648         struct nfs4_lock_state *lsp;
 649
 650         if (fl->fl_ops != NULL)
 651                 return 0;
 652         lsp = nfs4_get_lock_state(state, fl->fl_owner);
 653         if (lsp == NULL)
 654                 return -ENOMEM;
 655         fl->fl_u.nfs4_fl.owner = lsp;
 656         fl->fl_ops = &nfs4_fl_lock_ops;
 657         return 0;
 658 }
 659
 660 /*
 661  * Byte-range lock aware utility to initialize the stateid of read/write
 662  * requests.
 663  */
 664 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
 665 {
 666         struct nfs4_lock_state *lsp;
 667         int seq;
 668
 669         do {
 670                 seq = read_seqbegin(&state->seqlock);
 671                 memcpy(dst, &state->stateid, sizeof(*dst));
 672         } while (read_seqretry(&state->seqlock, seq));
 673         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 674                 return;
 675
 676         spin_lock(&state->state_lock);
 677         lsp = __nfs4_find_lock_state(state, fl_owner);
 678         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 679                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 680         spin_unlock(&state->state_lock);
 681         nfs4_put_lock_state(lsp);
 682 }
 683
 684 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
 685 {
 686         struct nfs_seqid *new;
 687
 688         new = kmalloc(sizeof(*new), GFP_KERNEL);
 689         if (new != NULL) {
 690                 new->sequence = counter;
 691                 INIT_LIST_HEAD(&new->list);
 692         }
 693         return new;
 694 }
 695
 696 void nfs_free_seqid(struct nfs_seqid *seqid)
 697 {
 698         if (!list_empty(&seqid->list)) {
 699                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 700
 701                 spin_lock(&sequence->lock);
 702                 list_del(&seqid->list);
 703                 spin_unlock(&sequence->lock);
 704                 rpc_wake_up(&sequence->wait);
 705         }
 706         kfree(seqid);
 707 }
 708
 709 /*
 710  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 711  * failed with a seqid incrementing error -
 712  * see comments nfs_fs.h:seqid_mutating_error()
 713  */
 714 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 715 {
 716         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 717         switch (status) {
 718                 case 0:
 719                         break;
 720                 case -NFS4ERR_BAD_SEQID:
 721                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
 722                                 return;
 723                         printk(KERN_WARNING "NFS: v4 server returned a bad"
 724                                         " sequence-id error on an"
 725                                         " unconfirmed sequence %p!\n",
 726                                         seqid->sequence);
 727                 case -NFS4ERR_STALE_CLIENTID:
 728                 case -NFS4ERR_STALE_STATEID:
 729                 case -NFS4ERR_BAD_STATEID:
 730                 case -NFS4ERR_BADXDR:
 731                 case -NFS4ERR_RESOURCE:
 732                 case -NFS4ERR_NOFILEHANDLE:
 733                         /* Non-seqid mutating errors */
 734                         return;
 735         };
 736         /*
 737          * Note: no locking needed as we are guaranteed to be first
 738          * on the sequence list
 739          */
 740         seqid->sequence->counter++;
 741 }
 742
 743 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
 744 {
 745         struct nfs4_state_owner *sp = container_of(seqid->sequence,
 746                                         struct nfs4_state_owner, so_seqid);
 747         struct nfs_server *server = sp->so_server;
 748
 749         if (status == -NFS4ERR_BAD_SEQID)
 750                 nfs4_drop_state_owner(sp);
 751         if (!nfs4_has_session(server->nfs_client))
 752                 nfs_increment_seqid(status, seqid);
 753 }
 754
 755 /*
 756  * Increment the seqid if the LOCK/LOCKU succeeded, or
 757  * failed with a seqid incrementing error -
 758  * see comments nfs_fs.h:seqid_mutating_error()
 759  */
 760 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
 761 {
 762         nfs_increment_seqid(status, seqid);
 763 }
 764
 765 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
 766 {
 767         struct rpc_sequence *sequence = seqid->sequence->sequence;
 768         int status = 0;
 769
 770         spin_lock(&sequence->lock);
 771         if (list_empty(&seqid->list))
 772                 list_add_tail(&seqid->list, &sequence->list);
 773         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
 774                 goto unlock;
 775         rpc_sleep_on(&sequence->wait, task, NULL);
 776         status = -EAGAIN;
 777 unlock:
 778         spin_unlock(&sequence->lock);
 779         return status;
 780 }
 781
 782 static int nfs4_run_state_manager(void *);
 783
 784 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
 785 {
 786         smp_mb__before_clear_bit();
 787         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
 788         smp_mb__after_clear_bit();
 789         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
 790         rpc_wake_up(&clp->cl_rpcwaitq);
 791 }
 792
 793 /*
 794  * Schedule the nfs_client asynchronous state management routine
 795  */
 796 void nfs4_schedule_state_manager(struct nfs_client *clp)
 797 {
 798         struct task_struct *task;
 799
 800         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
 801                 return;
 802         __module_get(THIS_MODULE);
 803         atomic_inc(&clp->cl_count);
 804         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
 805                                 rpc_peeraddr2str(clp->cl_rpcclient,
 806                                                         RPC_DISPLAY_ADDR));
 807         if (!IS_ERR(task))
 808                 return;
 809         nfs4_clear_state_manager_bit(clp);
 810         nfs_put_client(clp);
 811         module_put(THIS_MODULE);
 812 }
 813
 814 /*
 815  * Schedule a state recovery attempt
 816  */
 817 void nfs4_schedule_state_recovery(struct nfs_client *clp)
 818 {
 819         if (!clp)
 820                 return;
 821         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
 822                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
 823         nfs4_schedule_state_manager(clp);
 824 }
 825
 826 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
 827 {
 828
 829         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 830         /* Don't recover state that expired before the reboot */
 831         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
 832                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 833                 return 0;
 834         }
 835         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
 836         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
 837         return 1;
 838 }
 839
 840 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
 841 {
 842         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
 843         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 844         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
 845         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
 846         return 1;
 847 }
 848
 849 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
 850 {
 851         struct inode *inode = state->inode;
 852         struct nfs_inode *nfsi = NFS_I(inode);
 853         struct file_lock *fl;
 854         int status = 0;
 855
 856         if (inode->i_flock == NULL)
 857                 return 0;
 858
 859         /* Guard against delegation returns and new lock/unlock calls */
 860         down_write(&nfsi->rwsem);
 861         /* Protect inode->i_flock using the BKL */
 862         lock_kernel();
 863         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
 864                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
 865                         continue;
 866                 if (nfs_file_open_context(fl->fl_file)->state != state)
 867                         continue;
 868                 unlock_kernel();
 869                 status = ops->recover_lock(state, fl);
 870                 switch (status) {
 871                         case 0:
 872                                 break;
 873                         case -ESTALE:
 874                         case -NFS4ERR_ADMIN_REVOKED:
 875                         case -NFS4ERR_STALE_STATEID:
 876                         case -NFS4ERR_BAD_STATEID:
 877                         case -NFS4ERR_EXPIRED:
 878                         case -NFS4ERR_NO_GRACE:
 879                         case -NFS4ERR_STALE_CLIENTID:
 880                                 goto out;
 881                         default:
 882                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 883                                                 __func__, status);
 884                         case -ENOMEM:
 885                         case -NFS4ERR_DENIED:
 886                         case -NFS4ERR_RECLAIM_BAD:
 887                         case -NFS4ERR_RECLAIM_CONFLICT:
 888                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
 889                                 status = 0;
 890                 }
 891                 lock_kernel();
 892         }
 893         unlock_kernel();
 894 out:
 895         up_write(&nfsi->rwsem);
 896         return status;
 897 }
 898
 899 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
 900 {
 901         struct nfs4_state *state;
 902         struct nfs4_lock_state *lock;
 903         int status = 0;
 904
 905         /* Note: we rely on the sp->so_states list being ordered
 906          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
 907          * states first.
 908          * This is needed to ensure that the server won't give us any
 909          * read delegations that we have to return if, say, we are
 910          * recovering after a network partition or a reboot from a
 911          * server that doesn't support a grace period.
 912          */
 913 restart:
 914         spin_lock(&sp->so_lock);
 915         list_for_each_entry(state, &sp->so_states, open_states) {
 916                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
 917                         continue;
 918                 if (state->state == 0)
 919                         continue;
 920                 atomic_inc(&state->count);
 921                 spin_unlock(&sp->so_lock);
 922                 status = ops->recover_open(sp, state);
 923                 if (status >= 0) {
 924                         status = nfs4_reclaim_locks(state, ops);
 925                         if (status >= 0) {
 926                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
 927                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
 928                                                 printk("%s: Lock reclaim failed!\n",
 929                                                         __func__);
 930                                 }
 931                                 nfs4_put_open_state(state);
 932                                 goto restart;
 933                         }
 934                 }
 935                 switch (status) {
 936                         default:
 937                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 938                                                 __func__, status);
 939                         case -ENOENT:
 940                         case -ENOMEM:
 941                         case -ESTALE:
 942                                 /*
 943                                  * Open state on this file cannot be recovered
 944                                  * All we can do is revert to using the zero stateid.
 945                                  */
 946                                 memset(state->stateid.data, 0,
 947                                         sizeof(state->stateid.data));
 948                                 /* Mark the file as being 'closed' */
 949                                 state->state = 0;
 950                                 break;
 951                         case -NFS4ERR_ADMIN_REVOKED:
 952                         case -NFS4ERR_STALE_STATEID:
 953                         case -NFS4ERR_BAD_STATEID:
 954                         case -NFS4ERR_RECLAIM_BAD:
 955                         case -NFS4ERR_RECLAIM_CONFLICT:
 956                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
 957                                 break;
 958                         case -NFS4ERR_EXPIRED:
 959                         case -NFS4ERR_NO_GRACE:
 960                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
 961                         case -NFS4ERR_STALE_CLIENTID:
 962                                 goto out_err;
 963                 }
 964                 nfs4_put_open_state(state);
 965                 goto restart;
 966         }
 967         spin_unlock(&sp->so_lock);
 968         return 0;
 969 out_err:
 970         nfs4_put_open_state(state);
 971         return status;
 972 }
 973
 974 static void nfs4_clear_open_state(struct nfs4_state *state)
 975 {
 976         struct nfs4_lock_state *lock;
 977
 978         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 979         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
 980         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
 981         clear_bit(NFS_O_RDWR_STATE, &state->flags);
 982         list_for_each_entry(lock, &state->lock_states, ls_locks) {
 983                 lock->ls_seqid.flags = 0;
 984                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
 985         }
 986 }
 987
 988 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
 989 {
 990         struct nfs4_state_owner *sp;
 991         struct rb_node *pos;
 992         struct nfs4_state *state;
 993
 994         /* Reset all sequence ids to zero */
 995         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
 996                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 997                 sp->so_seqid.flags = 0;
 998                 spin_lock(&sp->so_lock);
 999                 list_for_each_entry(state, &sp->so_states, open_states) {
1000                         if (mark_reclaim(clp, state))
1001                                 nfs4_clear_open_state(state);
1002                 }
1003                 spin_unlock(&sp->so_lock);
1004         }
1005 }
1006
1007 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1008 {
1009         /* Mark all delegations for reclaim */
1010         nfs_delegation_mark_reclaim(clp);
1011         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1012 }
1013
1014 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1015 {
1016         struct nfs4_state_owner *sp;
1017         struct rb_node *pos;
1018         struct nfs4_state *state;
1019
1020         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1021                 return;
1022
1023         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1024                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1025                 spin_lock(&sp->so_lock);
1026                 list_for_each_entry(state, &sp->so_states, open_states) {
1027                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
1028                                 continue;
1029                         nfs4_state_mark_reclaim_nograce(clp, state);
1030                 }
1031                 spin_unlock(&sp->so_lock);
1032         }
1033
1034         nfs_delegation_reap_unclaimed(clp);
1035 }
1036
1037 static void nfs_delegation_clear_all(struct nfs_client *clp)
1038 {
1039         nfs_delegation_mark_reclaim(clp);
1040         nfs_delegation_reap_unclaimed(clp);
1041 }
1042
1043 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1044 {
1045         nfs_delegation_clear_all(clp);
1046         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1047 }
1048
1049 static void nfs4_state_end_reclaim_nograce(struct nfs_client *clp)
1050 {
1051         clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1052 }
1053
1054 static void nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1055 {
1056         switch (error) {
1057                 case -NFS4ERR_CB_PATH_DOWN:
1058                         nfs_handle_cb_pathdown(clp);
1059                         break;
1060                 case -NFS4ERR_STALE_CLIENTID:
1061                 case -NFS4ERR_LEASE_MOVED:
1062                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1063                         nfs4_state_start_reclaim_reboot(clp);
1064                         break;
1065                 case -NFS4ERR_EXPIRED:
1066                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1067                         nfs4_state_start_reclaim_nograce(clp);
1068                 case -NFS4ERR_BADSESSION:
1069                 case -NFS4ERR_BADSLOT:
1070                 case -NFS4ERR_BAD_HIGH_SLOT:
1071                 case -NFS4ERR_DEADSESSION:
1072                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1073                 case -NFS4ERR_SEQ_FALSE_RETRY:
1074                 case -NFS4ERR_SEQ_MISORDERED:
1075                         set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1076         }
1077 }
1078
1079 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1080 {
1081         struct rb_node *pos;
1082         int status = 0;
1083
1084 restart:
1085         spin_lock(&clp->cl_lock);
1086         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1087                 struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1088                 if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
1089                         continue;
1090                 atomic_inc(&sp->so_count);
1091                 spin_unlock(&clp->cl_lock);
1092                 status = nfs4_reclaim_open_state(sp, ops);
1093                 if (status < 0) {
1094                         set_bit(ops->owner_flag_bit, &sp->so_flags);
1095                         nfs4_put_state_owner(sp);
1096                         nfs4_recovery_handle_error(clp, status);
1097                         return status;
1098                 }
1099                 nfs4_put_state_owner(sp);
1100                 goto restart;
1101         }
1102         spin_unlock(&clp->cl_lock);
1103         return status;
1104 }
1105
1106 static int nfs4_check_lease(struct nfs_client *clp)
1107 {
1108         struct rpc_cred *cred;
1109         struct nfs4_state_maintenance_ops *ops =
1110                 nfs4_state_renewal_ops[clp->cl_minorversion];
1111         int status = -NFS4ERR_EXPIRED;
1112
1113         /* Is the client already known to have an expired lease? */
1114         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1115                 return 0;
1116         spin_lock(&clp->cl_lock);
1117         cred = ops->get_state_renewal_cred_locked(clp);
1118         spin_unlock(&clp->cl_lock);
1119         if (cred == NULL) {
1120                 cred = nfs4_get_setclientid_cred(clp);
1121                 if (cred == NULL)
1122                         goto out;
1123         }
1124         status = ops->renew_lease(clp, cred);
1125         put_rpccred(cred);
1126 out:
1127         nfs4_recovery_handle_error(clp, status);
1128         return status;
1129 }
1130
1131 static int nfs4_reclaim_lease(struct nfs_client *clp)
1132 {
1133         struct rpc_cred *cred;
1134         struct nfs4_state_recovery_ops *ops =
1135                 nfs4_reboot_recovery_ops[clp->cl_minorversion];
1136         int status = -ENOENT;
1137
1138         cred = ops->get_clid_cred(clp);
1139         if (cred != NULL) {
1140                 status = ops->establish_clid(clp, cred);
1141                 put_rpccred(cred);
1142                 /* Handle case where the user hasn't set up machine creds */
1143                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1144                         nfs4_clear_machine_cred(clp);
1145                         status = -EAGAIN;
1146                 }
1147                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1148                         status = -EPROTONOSUPPORT;
1149         }
1150         return status;
1151 }
1152
1153 #ifdef CONFIG_NFS_V4_1
1154 static void nfs4_session_recovery_handle_error(struct nfs_client *clp, int err)
1155 {
1156         switch (err) {
1157         case -NFS4ERR_STALE_CLIENTID:
1158                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1159                 set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1160         }
1161 }
1162
1163 static int nfs4_reset_session(struct nfs_client *clp)
1164 {
1165         int status;
1166
1167         status = nfs4_proc_destroy_session(clp->cl_session);
1168         if (status && status != -NFS4ERR_BADSESSION &&
1169             status != -NFS4ERR_DEADSESSION) {
1170                 nfs4_session_recovery_handle_error(clp, status);
1171                 goto out;
1172         }
1173
1174         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1175         status = nfs4_proc_create_session(clp, 1);
1176         if (status)
1177                 nfs4_session_recovery_handle_error(clp, status);
1178                 /* fall through*/
1179 out:
1180         /* Wake up the next rpc task even on error */
1181         rpc_wake_up_next(&clp->cl_session->fc_slot_table.slot_tbl_waitq);
1182         return status;
1183 }
1184
1185 static int nfs4_initialize_session(struct nfs_client *clp)
1186 {
1187         int status;
1188
1189         status = nfs4_proc_create_session(clp, 0);
1190         if (!status) {
1191                 nfs_mark_client_ready(clp, NFS_CS_READY);
1192         } else if (status == -NFS4ERR_STALE_CLIENTID) {
1193                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1194                 set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1195         } else {
1196                 nfs_mark_client_ready(clp, status);
1197         }
1198         return status;
1199 }
1200 #else /* CONFIG_NFS_V4_1 */
1201 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1202 static int nfs4_initialize_session(struct nfs_client *clp) { return 0; }
1203 #endif /* CONFIG_NFS_V4_1 */
1204
1205 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1206  * on EXCHANGE_ID for v4.1
1207  */
1208 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1209 {
1210         if (nfs4_has_session(clp)) {
1211                 switch (status) {
1212                 case -NFS4ERR_DELAY:
1213                 case -NFS4ERR_CLID_INUSE:
1214                 case -EAGAIN:
1215                         break;
1216
1217                 case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1218                                          * in nfs4_exchange_id */
1219                 default:
1220                         return;
1221                 }
1222         }
1223         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1224 }
1225
1226 static void nfs4_state_manager(struct nfs_client *clp)
1227 {
1228         int status = 0;
1229
1230         /* Ensure exclusive access to NFSv4 state */
1231         for(;;) {
1232                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1233                         /* We're going to have to re-establish a clientid */
1234                         status = nfs4_reclaim_lease(clp);
1235                         if (status) {
1236                                 nfs4_set_lease_expired(clp, status);
1237                                 if (status == -EAGAIN)
1238                                         continue;
1239                                 if (clp->cl_cons_state ==
1240                                                         NFS_CS_SESSION_INITING)
1241                                         nfs_mark_client_ready(clp, status);
1242                                 goto out_error;
1243                         }
1244                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1245                 }
1246
1247                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1248                         status = nfs4_check_lease(clp);
1249                         if (status != 0)
1250                                 continue;
1251                 }
1252                 /* Initialize or reset the session */
1253                 if (nfs4_has_session(clp) &&
1254                    test_and_clear_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state)) {
1255                         if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1256                                 status = nfs4_initialize_session(clp);
1257                         else
1258                                 status = nfs4_reset_session(clp);
1259                         if (status) {
1260                                 if (status == -NFS4ERR_STALE_CLIENTID)
1261                                         continue;
1262                                 goto out_error;
1263                         }
1264                 }
1265                 /* First recover reboot state... */
1266                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1267                         status = nfs4_do_reclaim(clp,
1268                                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1269                         if (status == -NFS4ERR_STALE_CLIENTID)
1270                                 continue;
1271                         if (test_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state))
1272                                 continue;
1273                         nfs4_state_end_reclaim_reboot(clp);
1274                         continue;
1275                 }
1276
1277                 /* Now recover expired state... */
1278                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1279                         status = nfs4_do_reclaim(clp,
1280                                 nfs4_nograce_recovery_ops[clp->cl_minorversion]);
1281                         if (status < 0) {
1282                                 set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1283                                 if (status == -NFS4ERR_STALE_CLIENTID)
1284                                         continue;
1285                                 if (status == -NFS4ERR_EXPIRED)
1286                                         continue;
1287                                 if (test_bit(NFS4CLNT_SESSION_SETUP,
1288                                                                 &clp->cl_state))
1289                                         continue;
1290                                 goto out_error;
1291                         } else
1292                                 nfs4_state_end_reclaim_nograce(clp);
1293                         continue;
1294                 }
1295
1296                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1297                         nfs_client_return_marked_delegations(clp);
1298                         continue;
1299                 }
1300
1301                 nfs4_clear_state_manager_bit(clp);
1302                 /* Did we race with an attempt to give us more work? */
1303                 if (clp->cl_state == 0)
1304                         break;
1305                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1306                         break;
1307         }
1308         return;
1309 out_error:
1310         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1311                         " with error %d\n", clp->cl_hostname, -status);
1312         if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1313                 nfs4_state_end_reclaim_reboot(clp);
1314         nfs4_clear_state_manager_bit(clp);
1315 }
1316
1317 static int nfs4_run_state_manager(void *ptr)
1318 {
1319         struct nfs_client *clp = ptr;
1320
1321         allow_signal(SIGKILL);
1322         nfs4_state_manager(clp);
1323         nfs_put_client(clp);
1324         module_put_and_exit(0);
1325         return 0;
1326 }
1327
1328 /*
1329  * Local variables:
1330  *  c-basic-offset: 8
1331  * End:
1332  */