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 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 120 {
 121         int status;
 122
 123         status = nfs4_proc_exchange_id(clp, cred);
 124         if (status == 0)
 125                 /* create session schedules state renewal upon success */
 126                 status = nfs4_proc_create_session(clp, 0);
 127         if (status == 0)
 128                 nfs_mark_client_ready(clp, NFS_CS_READY);
 129         return status;
 130 }
 131
 132 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 133 {
 134         struct rpc_cred *cred;
 135
 136         spin_lock(&clp->cl_lock);
 137         cred = nfs4_get_machine_cred_locked(clp);
 138         spin_unlock(&clp->cl_lock);
 139         return cred;
 140 }
 141
 142 #endif /* CONFIG_NFS_V4_1 */
 143
 144 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 145 {
 146         struct nfs4_state_owner *sp;
 147         struct rb_node *pos;
 148         struct rpc_cred *cred;
 149
 150         spin_lock(&clp->cl_lock);
 151         cred = nfs4_get_machine_cred_locked(clp);
 152         if (cred != NULL)
 153                 goto out;
 154         pos = rb_first(&clp->cl_state_owners);
 155         if (pos != NULL) {
 156                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 157                 cred = get_rpccred(sp->so_cred);
 158         }
 159 out:
 160         spin_unlock(&clp->cl_lock);
 161         return cred;
 162 }
 163
 164 static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
 165                 __u64 minval, int maxbits)
 166 {
 167         struct rb_node **p, *parent;
 168         struct nfs_unique_id *pos;
 169         __u64 mask = ~0ULL;
 170
 171         if (maxbits < 64)
 172                 mask = (1ULL << maxbits) - 1ULL;
 173
 174         /* Ensure distribution is more or less flat */
 175         get_random_bytes(&new->id, sizeof(new->id));
 176         new->id &= mask;
 177         if (new->id < minval)
 178                 new->id += minval;
 179 retry:
 180         p = &root->rb_node;
 181         parent = NULL;
 182
 183         while (*p != NULL) {
 184                 parent = *p;
 185                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 186
 187                 if (new->id < pos->id)
 188                         p = &(*p)->rb_left;
 189                 else if (new->id > pos->id)
 190                         p = &(*p)->rb_right;
 191                 else
 192                         goto id_exists;
 193         }
 194         rb_link_node(&new->rb_node, parent, p);
 195         rb_insert_color(&new->rb_node, root);
 196         return;
 197 id_exists:
 198         for (;;) {
 199                 new->id++;
 200                 if (new->id < minval || (new->id & mask) != new->id) {
 201                         new->id = minval;
 202                         break;
 203                 }
 204                 parent = rb_next(parent);
 205                 if (parent == NULL)
 206                         break;
 207                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 208                 if (new->id < pos->id)
 209                         break;
 210         }
 211         goto retry;
 212 }
 213
 214 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
 215 {
 216         rb_erase(&id->rb_node, root);
 217 }
 218
 219 static struct nfs4_state_owner *
 220 nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 221 {
 222         struct nfs_client *clp = server->nfs_client;
 223         struct rb_node **p = &clp->cl_state_owners.rb_node,
 224                        *parent = NULL;
 225         struct nfs4_state_owner *sp, *res = NULL;
 226
 227         while (*p != NULL) {
 228                 parent = *p;
 229                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 230
 231                 if (server < sp->so_server) {
 232                         p = &parent->rb_left;
 233                         continue;
 234                 }
 235                 if (server > sp->so_server) {
 236                         p = &parent->rb_right;
 237                         continue;
 238                 }
 239                 if (cred < sp->so_cred)
 240                         p = &parent->rb_left;
 241                 else if (cred > sp->so_cred)
 242                         p = &parent->rb_right;
 243                 else {
 244                         atomic_inc(&sp->so_count);
 245                         res = sp;
 246                         break;
 247                 }
 248         }
 249         return res;
 250 }
 251
 252 static struct nfs4_state_owner *
 253 nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
 254 {
 255         struct rb_node **p = &clp->cl_state_owners.rb_node,
 256                        *parent = NULL;
 257         struct nfs4_state_owner *sp;
 258
 259         while (*p != NULL) {
 260                 parent = *p;
 261                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 262
 263                 if (new->so_server < sp->so_server) {
 264                         p = &parent->rb_left;
 265                         continue;
 266                 }
 267                 if (new->so_server > sp->so_server) {
 268                         p = &parent->rb_right;
 269                         continue;
 270                 }
 271                 if (new->so_cred < sp->so_cred)
 272                         p = &parent->rb_left;
 273                 else if (new->so_cred > sp->so_cred)
 274                         p = &parent->rb_right;
 275                 else {
 276                         atomic_inc(&sp->so_count);
 277                         return sp;
 278                 }
 279         }
 280         nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
 281         rb_link_node(&new->so_client_node, parent, p);
 282         rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
 283         return new;
 284 }
 285
 286 static void
 287 nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
 288 {
 289         if (!RB_EMPTY_NODE(&sp->so_client_node))
 290                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 291         nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
 292 }
 293
 294 /*
 295  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 296  * create a new state_owner.
 297  *
 298  */
 299 static struct nfs4_state_owner *
 300 nfs4_alloc_state_owner(void)
 301 {
 302         struct nfs4_state_owner *sp;
 303
 304         sp = kzalloc(sizeof(*sp),GFP_KERNEL);
 305         if (!sp)
 306                 return NULL;
 307         spin_lock_init(&sp->so_lock);
 308         INIT_LIST_HEAD(&sp->so_states);
 309         INIT_LIST_HEAD(&sp->so_delegations);
 310         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 311         sp->so_seqid.sequence = &sp->so_sequence;
 312         spin_lock_init(&sp->so_sequence.lock);
 313         INIT_LIST_HEAD(&sp->so_sequence.list);
 314         atomic_set(&sp->so_count, 1);
 315         return sp;
 316 }
 317
 318 static void
 319 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 320 {
 321         if (!RB_EMPTY_NODE(&sp->so_client_node)) {
 322                 struct nfs_client *clp = sp->so_client;
 323
 324                 spin_lock(&clp->cl_lock);
 325                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 326                 RB_CLEAR_NODE(&sp->so_client_node);
 327                 spin_unlock(&clp->cl_lock);
 328         }
 329 }
 330
 331 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 332 {
 333         struct nfs_client *clp = server->nfs_client;
 334         struct nfs4_state_owner *sp, *new;
 335
 336         spin_lock(&clp->cl_lock);
 337         sp = nfs4_find_state_owner(server, cred);
 338         spin_unlock(&clp->cl_lock);
 339         if (sp != NULL)
 340                 return sp;
 341         new = nfs4_alloc_state_owner();
 342         if (new == NULL)
 343                 return NULL;
 344         new->so_client = clp;
 345         new->so_server = server;
 346         new->so_cred = cred;
 347         spin_lock(&clp->cl_lock);
 348         sp = nfs4_insert_state_owner(clp, new);
 349         spin_unlock(&clp->cl_lock);
 350         if (sp == new)
 351                 get_rpccred(cred);
 352         else {
 353                 rpc_destroy_wait_queue(&new->so_sequence.wait);
 354                 kfree(new);
 355         }
 356         return sp;
 357 }
 358
 359 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 360 {
 361         struct nfs_client *clp = sp->so_client;
 362         struct rpc_cred *cred = sp->so_cred;
 363
 364         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 365                 return;
 366         nfs4_remove_state_owner(clp, sp);
 367         spin_unlock(&clp->cl_lock);
 368         rpc_destroy_wait_queue(&sp->so_sequence.wait);
 369         put_rpccred(cred);
 370         kfree(sp);
 371 }
 372
 373 static struct nfs4_state *
 374 nfs4_alloc_open_state(void)
 375 {
 376         struct nfs4_state *state;
 377
 378         state = kzalloc(sizeof(*state), GFP_KERNEL);
 379         if (!state)
 380                 return NULL;
 381         atomic_set(&state->count, 1);
 382         INIT_LIST_HEAD(&state->lock_states);
 383         spin_lock_init(&state->state_lock);
 384         seqlock_init(&state->seqlock);
 385         return state;
 386 }
 387
 388 void
 389 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 390 {
 391         if (state->state == fmode)
 392                 return;
 393         /* NB! List reordering - see the reclaim code for why.  */
 394         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 395                 if (fmode & FMODE_WRITE)
 396                         list_move(&state->open_states, &state->owner->so_states);
 397                 else
 398                         list_move_tail(&state->open_states, &state->owner->so_states);
 399         }
 400         state->state = fmode;
 401 }
 402
 403 static struct nfs4_state *
 404 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 405 {
 406         struct nfs_inode *nfsi = NFS_I(inode);
 407         struct nfs4_state *state;
 408
 409         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 410                 if (state->owner != owner)
 411                         continue;
 412                 if (atomic_inc_not_zero(&state->count))
 413                         return state;
 414         }
 415         return NULL;
 416 }
 417
 418 static void
 419 nfs4_free_open_state(struct nfs4_state *state)
 420 {
 421         kfree(state);
 422 }
 423
 424 struct nfs4_state *
 425 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 426 {
 427         struct nfs4_state *state, *new;
 428         struct nfs_inode *nfsi = NFS_I(inode);
 429
 430         spin_lock(&inode->i_lock);
 431         state = __nfs4_find_state_byowner(inode, owner);
 432         spin_unlock(&inode->i_lock);
 433         if (state)
 434                 goto out;
 435         new = nfs4_alloc_open_state();
 436         spin_lock(&owner->so_lock);
 437         spin_lock(&inode->i_lock);
 438         state = __nfs4_find_state_byowner(inode, owner);
 439         if (state == NULL && new != NULL) {
 440                 state = new;
 441                 state->owner = owner;
 442                 atomic_inc(&owner->so_count);
 443                 list_add(&state->inode_states, &nfsi->open_states);
 444                 state->inode = igrab(inode);
 445                 spin_unlock(&inode->i_lock);
 446                 /* Note: The reclaim code dictates that we add stateless
 447                  * and read-only stateids to the end of the list */
 448                 list_add_tail(&state->open_states, &owner->so_states);
 449                 spin_unlock(&owner->so_lock);
 450         } else {
 451                 spin_unlock(&inode->i_lock);
 452                 spin_unlock(&owner->so_lock);
 453                 if (new)
 454                         nfs4_free_open_state(new);
 455         }
 456 out:
 457         return state;
 458 }
 459
 460 void nfs4_put_open_state(struct nfs4_state *state)
 461 {
 462         struct inode *inode = state->inode;
 463         struct nfs4_state_owner *owner = state->owner;
 464
 465         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 466                 return;
 467         spin_lock(&inode->i_lock);
 468         list_del(&state->inode_states);
 469         list_del(&state->open_states);
 470         spin_unlock(&inode->i_lock);
 471         spin_unlock(&owner->so_lock);
 472         iput(inode);
 473         nfs4_free_open_state(state);
 474         nfs4_put_state_owner(owner);
 475 }
 476
 477 /*
 478  * Close the current file.
 479  */
 480 static void __nfs4_close(struct path *path, struct nfs4_state *state, fmode_t fmode, int wait)
 481 {
 482         struct nfs4_state_owner *owner = state->owner;
 483         int call_close = 0;
 484         fmode_t newstate;
 485
 486         atomic_inc(&owner->so_count);
 487         /* Protect against nfs4_find_state() */
 488         spin_lock(&owner->so_lock);
 489         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 490                 case FMODE_READ:
 491                         state->n_rdonly--;
 492                         break;
 493                 case FMODE_WRITE:
 494                         state->n_wronly--;
 495                         break;
 496                 case FMODE_READ|FMODE_WRITE:
 497                         state->n_rdwr--;
 498         }
 499         newstate = FMODE_READ|FMODE_WRITE;
 500         if (state->n_rdwr == 0) {
 501                 if (state->n_rdonly == 0) {
 502                         newstate &= ~FMODE_READ;
 503                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 504                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 505                 }
 506                 if (state->n_wronly == 0) {
 507                         newstate &= ~FMODE_WRITE;
 508                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 509                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 510                 }
 511                 if (newstate == 0)
 512                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 513         }
 514         nfs4_state_set_mode_locked(state, newstate);
 515         spin_unlock(&owner->so_lock);
 516
 517         if (!call_close) {
 518                 nfs4_put_open_state(state);
 519                 nfs4_put_state_owner(owner);
 520         } else
 521                 nfs4_do_close(path, state, wait);
 522 }
 523
 524 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
 525 {
 526         __nfs4_close(path, state, fmode, 0);
 527 }
 528
 529 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
 530 {
 531         __nfs4_close(path, state, fmode, 1);
 532 }
 533
 534 /*
 535  * Search the state->lock_states for an existing lock_owner
 536  * that is compatible with current->files
 537  */
 538 static struct nfs4_lock_state *
 539 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 540 {
 541         struct nfs4_lock_state *pos;
 542         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 543                 if (pos->ls_owner != fl_owner)
 544                         continue;
 545                 atomic_inc(&pos->ls_count);
 546                 return pos;
 547         }
 548         return NULL;
 549 }
 550
 551 /*
 552  * Return a compatible lock_state. If no initialized lock_state structure
 553  * exists, return an uninitialized one.
 554  *
 555  */
 556 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 557 {
 558         struct nfs4_lock_state *lsp;
 559         struct nfs_client *clp = state->owner->so_client;
 560
 561         lsp = kzalloc(sizeof(*lsp), GFP_KERNEL);
 562         if (lsp == NULL)
 563                 return NULL;
 564         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 565         spin_lock_init(&lsp->ls_sequence.lock);
 566         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 567         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 568         atomic_set(&lsp->ls_count, 1);
 569         lsp->ls_state = state;
 570         lsp->ls_owner = fl_owner;
 571         spin_lock(&clp->cl_lock);
 572         nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
 573         spin_unlock(&clp->cl_lock);
 574         INIT_LIST_HEAD(&lsp->ls_locks);
 575         return lsp;
 576 }
 577
 578 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 579 {
 580         struct nfs_client *clp = lsp->ls_state->owner->so_client;
 581
 582         spin_lock(&clp->cl_lock);
 583         nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
 584         spin_unlock(&clp->cl_lock);
 585         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 586         kfree(lsp);
 587 }
 588
 589 /*
 590  * Return a compatible lock_state. If no initialized lock_state structure
 591  * exists, return an uninitialized one.
 592  *
 593  */
 594 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 595 {
 596         struct nfs4_lock_state *lsp, *new = NULL;
 597
 598         for(;;) {
 599                 spin_lock(&state->state_lock);
 600                 lsp = __nfs4_find_lock_state(state, owner);
 601                 if (lsp != NULL)
 602                         break;
 603                 if (new != NULL) {
 604                         list_add(&new->ls_locks, &state->lock_states);
 605                         set_bit(LK_STATE_IN_USE, &state->flags);
 606                         lsp = new;
 607                         new = NULL;
 608                         break;
 609                 }
 610                 spin_unlock(&state->state_lock);
 611                 new = nfs4_alloc_lock_state(state, owner);
 612                 if (new == NULL)
 613                         return NULL;
 614         }
 615         spin_unlock(&state->state_lock);
 616         if (new != NULL)
 617                 nfs4_free_lock_state(new);
 618         return lsp;
 619 }
 620
 621 /*
 622  * Release reference to lock_state, and free it if we see that
 623  * it is no longer in use
 624  */
 625 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 626 {
 627         struct nfs4_state *state;
 628
 629         if (lsp == NULL)
 630                 return;
 631         state = lsp->ls_state;
 632         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 633                 return;
 634         list_del(&lsp->ls_locks);
 635         if (list_empty(&state->lock_states))
 636                 clear_bit(LK_STATE_IN_USE, &state->flags);
 637         spin_unlock(&state->state_lock);
 638         nfs4_free_lock_state(lsp);
 639 }
 640
 641 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 642 {
 643         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 644
 645         dst->fl_u.nfs4_fl.owner = lsp;
 646         atomic_inc(&lsp->ls_count);
 647 }
 648
 649 static void nfs4_fl_release_lock(struct file_lock *fl)
 650 {
 651         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 652 }
 653
 654 static const struct file_lock_operations nfs4_fl_lock_ops = {
 655         .fl_copy_lock = nfs4_fl_copy_lock,
 656         .fl_release_private = nfs4_fl_release_lock,
 657 };
 658
 659 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 660 {
 661         struct nfs4_lock_state *lsp;
 662
 663         if (fl->fl_ops != NULL)
 664                 return 0;
 665         lsp = nfs4_get_lock_state(state, fl->fl_owner);
 666         if (lsp == NULL)
 667                 return -ENOMEM;
 668         fl->fl_u.nfs4_fl.owner = lsp;
 669         fl->fl_ops = &nfs4_fl_lock_ops;
 670         return 0;
 671 }
 672
 673 /*
 674  * Byte-range lock aware utility to initialize the stateid of read/write
 675  * requests.
 676  */
 677 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
 678 {
 679         struct nfs4_lock_state *lsp;
 680         int seq;
 681
 682         do {
 683                 seq = read_seqbegin(&state->seqlock);
 684                 memcpy(dst, &state->stateid, sizeof(*dst));
 685         } while (read_seqretry(&state->seqlock, seq));
 686         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 687                 return;
 688
 689         spin_lock(&state->state_lock);
 690         lsp = __nfs4_find_lock_state(state, fl_owner);
 691         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 692                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 693         spin_unlock(&state->state_lock);
 694         nfs4_put_lock_state(lsp);
 695 }
 696
 697 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
 698 {
 699         struct nfs_seqid *new;
 700
 701         new = kmalloc(sizeof(*new), GFP_KERNEL);
 702         if (new != NULL) {
 703                 new->sequence = counter;
 704                 INIT_LIST_HEAD(&new->list);
 705         }
 706         return new;
 707 }
 708
 709 void nfs_free_seqid(struct nfs_seqid *seqid)
 710 {
 711         if (!list_empty(&seqid->list)) {
 712                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 713
 714                 spin_lock(&sequence->lock);
 715                 list_del(&seqid->list);
 716                 spin_unlock(&sequence->lock);
 717                 rpc_wake_up(&sequence->wait);
 718         }
 719         kfree(seqid);
 720 }
 721
 722 /*
 723  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 724  * failed with a seqid incrementing error -
 725  * see comments nfs_fs.h:seqid_mutating_error()
 726  */
 727 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 728 {
 729         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 730         switch (status) {
 731                 case 0:
 732                         break;
 733                 case -NFS4ERR_BAD_SEQID:
 734                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
 735                                 return;
 736                         printk(KERN_WARNING "NFS: v4 server returned a bad"
 737                                         " sequence-id error on an"
 738                                         " unconfirmed sequence %p!\n",
 739                                         seqid->sequence);
 740                 case -NFS4ERR_STALE_CLIENTID:
 741                 case -NFS4ERR_STALE_STATEID:
 742                 case -NFS4ERR_BAD_STATEID:
 743                 case -NFS4ERR_BADXDR:
 744                 case -NFS4ERR_RESOURCE:
 745                 case -NFS4ERR_NOFILEHANDLE:
 746                         /* Non-seqid mutating errors */
 747                         return;
 748         };
 749         /*
 750          * Note: no locking needed as we are guaranteed to be first
 751          * on the sequence list
 752          */
 753         seqid->sequence->counter++;
 754 }
 755
 756 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
 757 {
 758         struct nfs4_state_owner *sp = container_of(seqid->sequence,
 759                                         struct nfs4_state_owner, so_seqid);
 760         struct nfs_server *server = sp->so_server;
 761
 762         if (status == -NFS4ERR_BAD_SEQID)
 763                 nfs4_drop_state_owner(sp);
 764         if (!nfs4_has_session(server->nfs_client))
 765                 nfs_increment_seqid(status, seqid);
 766 }
 767
 768 /*
 769  * Increment the seqid if the LOCK/LOCKU succeeded, or
 770  * failed with a seqid incrementing error -
 771  * see comments nfs_fs.h:seqid_mutating_error()
 772  */
 773 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
 774 {
 775         nfs_increment_seqid(status, seqid);
 776 }
 777
 778 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
 779 {
 780         struct rpc_sequence *sequence = seqid->sequence->sequence;
 781         int status = 0;
 782
 783         spin_lock(&sequence->lock);
 784         if (list_empty(&seqid->list))
 785                 list_add_tail(&seqid->list, &sequence->list);
 786         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
 787                 goto unlock;
 788         rpc_sleep_on(&sequence->wait, task, NULL);
 789         status = -EAGAIN;
 790 unlock:
 791         spin_unlock(&sequence->lock);
 792         return status;
 793 }
 794
 795 static int nfs4_run_state_manager(void *);
 796
 797 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
 798 {
 799         smp_mb__before_clear_bit();
 800         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
 801         smp_mb__after_clear_bit();
 802         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
 803         rpc_wake_up(&clp->cl_rpcwaitq);
 804 }
 805
 806 /*
 807  * Schedule the nfs_client asynchronous state management routine
 808  */
 809 void nfs4_schedule_state_manager(struct nfs_client *clp)
 810 {
 811         struct task_struct *task;
 812
 813         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
 814                 return;
 815         __module_get(THIS_MODULE);
 816         atomic_inc(&clp->cl_count);
 817         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
 818                                 rpc_peeraddr2str(clp->cl_rpcclient,
 819                                                         RPC_DISPLAY_ADDR));
 820         if (!IS_ERR(task))
 821                 return;
 822         nfs4_clear_state_manager_bit(clp);
 823         nfs_put_client(clp);
 824         module_put(THIS_MODULE);
 825 }
 826
 827 /*
 828  * Schedule a state recovery attempt
 829  */
 830 void nfs4_schedule_state_recovery(struct nfs_client *clp)
 831 {
 832         if (!clp)
 833                 return;
 834         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
 835                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
 836         nfs4_schedule_state_manager(clp);
 837 }
 838
 839 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
 840 {
 841
 842         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 843         /* Don't recover state that expired before the reboot */
 844         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
 845                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 846                 return 0;
 847         }
 848         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
 849         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
 850         return 1;
 851 }
 852
 853 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
 854 {
 855         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
 856         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 857         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
 858         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
 859         return 1;
 860 }
 861
 862 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
 863 {
 864         struct inode *inode = state->inode;
 865         struct nfs_inode *nfsi = NFS_I(inode);
 866         struct file_lock *fl;
 867         int status = 0;
 868
 869         if (inode->i_flock == NULL)
 870                 return 0;
 871
 872         /* Guard against delegation returns and new lock/unlock calls */
 873         down_write(&nfsi->rwsem);
 874         /* Protect inode->i_flock using the BKL */
 875         lock_kernel();
 876         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
 877                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
 878                         continue;
 879                 if (nfs_file_open_context(fl->fl_file)->state != state)
 880                         continue;
 881                 unlock_kernel();
 882                 status = ops->recover_lock(state, fl);
 883                 switch (status) {
 884                         case 0:
 885                                 break;
 886                         case -ESTALE:
 887                         case -NFS4ERR_ADMIN_REVOKED:
 888                         case -NFS4ERR_STALE_STATEID:
 889                         case -NFS4ERR_BAD_STATEID:
 890                         case -NFS4ERR_EXPIRED:
 891                         case -NFS4ERR_NO_GRACE:
 892                         case -NFS4ERR_STALE_CLIENTID:
 893                         case -NFS4ERR_BADSESSION:
 894                         case -NFS4ERR_BADSLOT:
 895                         case -NFS4ERR_BAD_HIGH_SLOT:
 896                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 897                                 goto out;
 898                         default:
 899                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 900                                                 __func__, status);
 901                         case -ENOMEM:
 902                         case -NFS4ERR_DENIED:
 903                         case -NFS4ERR_RECLAIM_BAD:
 904                         case -NFS4ERR_RECLAIM_CONFLICT:
 905                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
 906                                 status = 0;
 907                 }
 908                 lock_kernel();
 909         }
 910         unlock_kernel();
 911 out:
 912         up_write(&nfsi->rwsem);
 913         return status;
 914 }
 915
 916 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
 917 {
 918         struct nfs4_state *state;
 919         struct nfs4_lock_state *lock;
 920         int status = 0;
 921
 922         /* Note: we rely on the sp->so_states list being ordered
 923          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
 924          * states first.
 925          * This is needed to ensure that the server won't give us any
 926          * read delegations that we have to return if, say, we are
 927          * recovering after a network partition or a reboot from a
 928          * server that doesn't support a grace period.
 929          */
 930 restart:
 931         spin_lock(&sp->so_lock);
 932         list_for_each_entry(state, &sp->so_states, open_states) {
 933                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
 934                         continue;
 935                 if (state->state == 0)
 936                         continue;
 937                 atomic_inc(&state->count);
 938                 spin_unlock(&sp->so_lock);
 939                 status = ops->recover_open(sp, state);
 940                 if (status >= 0) {
 941                         status = nfs4_reclaim_locks(state, ops);
 942                         if (status >= 0) {
 943                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
 944                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
 945                                                 printk("%s: Lock reclaim failed!\n",
 946                                                         __func__);
 947                                 }
 948                                 nfs4_put_open_state(state);
 949                                 goto restart;
 950                         }
 951                 }
 952                 switch (status) {
 953                         default:
 954                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 955                                                 __func__, status);
 956                         case -ENOENT:
 957                         case -ENOMEM:
 958                         case -ESTALE:
 959                                 /*
 960                                  * Open state on this file cannot be recovered
 961                                  * All we can do is revert to using the zero stateid.
 962                                  */
 963                                 memset(state->stateid.data, 0,
 964                                         sizeof(state->stateid.data));
 965                                 /* Mark the file as being 'closed' */
 966                                 state->state = 0;
 967                                 break;
 968                         case -NFS4ERR_ADMIN_REVOKED:
 969                         case -NFS4ERR_STALE_STATEID:
 970                         case -NFS4ERR_BAD_STATEID:
 971                         case -NFS4ERR_RECLAIM_BAD:
 972                         case -NFS4ERR_RECLAIM_CONFLICT:
 973                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
 974                                 break;
 975                         case -NFS4ERR_EXPIRED:
 976                         case -NFS4ERR_NO_GRACE:
 977                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
 978                         case -NFS4ERR_STALE_CLIENTID:
 979                         case -NFS4ERR_BADSESSION:
 980                         case -NFS4ERR_BADSLOT:
 981                         case -NFS4ERR_BAD_HIGH_SLOT:
 982                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 983                                 goto out_err;
 984                 }
 985                 nfs4_put_open_state(state);
 986                 goto restart;
 987         }
 988         spin_unlock(&sp->so_lock);
 989         return 0;
 990 out_err:
 991         nfs4_put_open_state(state);
 992         return status;
 993 }
 994
 995 static void nfs4_clear_open_state(struct nfs4_state *state)
 996 {
 997         struct nfs4_lock_state *lock;
 998
 999         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1000         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1001         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1002         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1003         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1004                 lock->ls_seqid.flags = 0;
1005                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1006         }
1007 }
1008
1009 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1010 {
1011         struct nfs4_state_owner *sp;
1012         struct rb_node *pos;
1013         struct nfs4_state *state;
1014
1015         /* Reset all sequence ids to zero */
1016         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1017                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1018                 sp->so_seqid.flags = 0;
1019                 spin_lock(&sp->so_lock);
1020                 list_for_each_entry(state, &sp->so_states, open_states) {
1021                         if (mark_reclaim(clp, state))
1022                                 nfs4_clear_open_state(state);
1023                 }
1024                 spin_unlock(&sp->so_lock);
1025         }
1026 }
1027
1028 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1029 {
1030         /* Mark all delegations for reclaim */
1031         nfs_delegation_mark_reclaim(clp);
1032         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1033 }
1034
1035 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1036 {
1037         struct nfs4_state_owner *sp;
1038         struct rb_node *pos;
1039         struct nfs4_state *state;
1040
1041         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1042                 return;
1043
1044         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1045                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1046                 spin_lock(&sp->so_lock);
1047                 list_for_each_entry(state, &sp->so_states, open_states) {
1048                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
1049                                 continue;
1050                         nfs4_state_mark_reclaim_nograce(clp, state);
1051                 }
1052                 spin_unlock(&sp->so_lock);
1053         }
1054
1055         nfs_delegation_reap_unclaimed(clp);
1056 }
1057
1058 static void nfs_delegation_clear_all(struct nfs_client *clp)
1059 {
1060         nfs_delegation_mark_reclaim(clp);
1061         nfs_delegation_reap_unclaimed(clp);
1062 }
1063
1064 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1065 {
1066         nfs_delegation_clear_all(clp);
1067         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1068 }
1069
1070 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1071 {
1072         switch (error) {
1073                 case -NFS4ERR_CB_PATH_DOWN:
1074                         nfs_handle_cb_pathdown(clp);
1075                         return 0;
1076                 case -NFS4ERR_NO_GRACE:
1077                         nfs4_state_end_reclaim_reboot(clp);
1078                         return 0;
1079                 case -NFS4ERR_STALE_CLIENTID:
1080                 case -NFS4ERR_LEASE_MOVED:
1081                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1082                         nfs4_state_end_reclaim_reboot(clp);
1083                         nfs4_state_start_reclaim_reboot(clp);
1084                         break;
1085                 case -NFS4ERR_EXPIRED:
1086                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1087                         nfs4_state_start_reclaim_nograce(clp);
1088                         break;
1089                 case -NFS4ERR_BADSESSION:
1090                 case -NFS4ERR_BADSLOT:
1091                 case -NFS4ERR_BAD_HIGH_SLOT:
1092                 case -NFS4ERR_DEADSESSION:
1093                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1094                 case -NFS4ERR_SEQ_FALSE_RETRY:
1095                 case -NFS4ERR_SEQ_MISORDERED:
1096                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1097                         /* Zero session reset errors */
1098                         return 0;
1099         }
1100         return error;
1101 }
1102
1103 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1104 {
1105         struct rb_node *pos;
1106         int status = 0;
1107
1108 restart:
1109         spin_lock(&clp->cl_lock);
1110         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1111                 struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1112                 if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
1113                         continue;
1114                 atomic_inc(&sp->so_count);
1115                 spin_unlock(&clp->cl_lock);
1116                 status = nfs4_reclaim_open_state(sp, ops);
1117                 if (status < 0) {
1118                         set_bit(ops->owner_flag_bit, &sp->so_flags);
1119                         nfs4_put_state_owner(sp);
1120                         return nfs4_recovery_handle_error(clp, status);
1121                 }
1122                 nfs4_put_state_owner(sp);
1123                 goto restart;
1124         }
1125         spin_unlock(&clp->cl_lock);
1126         return status;
1127 }
1128
1129 static int nfs4_check_lease(struct nfs_client *clp)
1130 {
1131         struct rpc_cred *cred;
1132         struct nfs4_state_maintenance_ops *ops =
1133                 nfs4_state_renewal_ops[clp->cl_minorversion];
1134         int status = -NFS4ERR_EXPIRED;
1135
1136         /* Is the client already known to have an expired lease? */
1137         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1138                 return 0;
1139         spin_lock(&clp->cl_lock);
1140         cred = ops->get_state_renewal_cred_locked(clp);
1141         spin_unlock(&clp->cl_lock);
1142         if (cred == NULL) {
1143                 cred = nfs4_get_setclientid_cred(clp);
1144                 if (cred == NULL)
1145                         goto out;
1146         }
1147         status = ops->renew_lease(clp, cred);
1148         put_rpccred(cred);
1149 out:
1150         return nfs4_recovery_handle_error(clp, status);
1151 }
1152
1153 static int nfs4_reclaim_lease(struct nfs_client *clp)
1154 {
1155         struct rpc_cred *cred;
1156         struct nfs4_state_recovery_ops *ops =
1157                 nfs4_reboot_recovery_ops[clp->cl_minorversion];
1158         int status = -ENOENT;
1159
1160         cred = ops->get_clid_cred(clp);
1161         if (cred != NULL) {
1162                 status = ops->establish_clid(clp, cred);
1163                 put_rpccred(cred);
1164                 /* Handle case where the user hasn't set up machine creds */
1165                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1166                         nfs4_clear_machine_cred(clp);
1167                         status = -EAGAIN;
1168                 }
1169                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1170                         status = -EPROTONOSUPPORT;
1171         }
1172         return status;
1173 }
1174
1175 #ifdef CONFIG_NFS_V4_1
1176 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1177 {
1178         if (!flags)
1179                 return;
1180         else if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED) {
1181                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1182                 nfs4_state_start_reclaim_reboot(clp);
1183                 nfs4_schedule_state_recovery(clp);
1184         } else if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1185                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1186                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1187                             SEQ4_STATUS_RECALLABLE_STATE_REVOKED |
1188                             SEQ4_STATUS_LEASE_MOVED)) {
1189                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1190                 nfs4_state_start_reclaim_nograce(clp);
1191                 nfs4_schedule_state_recovery(clp);
1192         } else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1193                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1194                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1195                 nfs_expire_all_delegations(clp);
1196 }
1197
1198 static void nfs4_session_recovery_handle_error(struct nfs_client *clp, int err)
1199 {
1200         switch (err) {
1201         case -NFS4ERR_STALE_CLIENTID:
1202                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1203         }
1204 }
1205
1206 static int nfs4_reset_session(struct nfs_client *clp)
1207 {
1208         struct nfs4_session *ses = clp->cl_session;
1209         struct nfs4_slot_table *tbl = &ses->fc_slot_table;
1210         int status;
1211
1212         INIT_COMPLETION(ses->complete);
1213         spin_lock(&tbl->slot_tbl_lock);
1214         set_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state);
1215         if (tbl->highest_used_slotid != -1) {
1216                 spin_unlock(&tbl->slot_tbl_lock);
1217                 status = wait_for_completion_interruptible(&ses->complete);
1218                 if (status) /* -ERESTARTSYS */
1219                         goto out;
1220         } else {
1221                 spin_unlock(&tbl->slot_tbl_lock);
1222         }
1223
1224         status = nfs4_proc_destroy_session(clp->cl_session);
1225         if (status && status != -NFS4ERR_BADSESSION &&
1226             status != -NFS4ERR_DEADSESSION) {
1227                 nfs4_session_recovery_handle_error(clp, status);
1228                 goto out;
1229         }
1230
1231         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1232         status = nfs4_proc_create_session(clp, 1);
1233         if (status)
1234                 nfs4_session_recovery_handle_error(clp, status);
1235                 /* fall through*/
1236 out:
1237         /* Wake up the next rpc task even on error */
1238         clear_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state);
1239         rpc_wake_up_next(&clp->cl_session->fc_slot_table.slot_tbl_waitq);
1240         return status;
1241 }
1242
1243 #else /* CONFIG_NFS_V4_1 */
1244 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1245 #endif /* CONFIG_NFS_V4_1 */
1246
1247 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1248  * on EXCHANGE_ID for v4.1
1249  */
1250 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1251 {
1252         if (nfs4_has_session(clp)) {
1253                 switch (status) {
1254                 case -NFS4ERR_DELAY:
1255                 case -NFS4ERR_CLID_INUSE:
1256                 case -EAGAIN:
1257                         break;
1258
1259                 case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1260                                          * in nfs4_exchange_id */
1261                 default:
1262                         return;
1263                 }
1264         }
1265         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1266 }
1267
1268 static void nfs4_state_manager(struct nfs_client *clp)
1269 {
1270         int status = 0;
1271
1272         /* Ensure exclusive access to NFSv4 state */
1273         for(;;) {
1274                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1275                         /* We're going to have to re-establish a clientid */
1276                         status = nfs4_reclaim_lease(clp);
1277                         if (status) {
1278                                 nfs4_set_lease_expired(clp, status);
1279                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1280                                                         &clp->cl_state))
1281                                         continue;
1282                                 if (clp->cl_cons_state ==
1283                                                         NFS_CS_SESSION_INITING)
1284                                         nfs_mark_client_ready(clp, status);
1285                                 goto out_error;
1286                         }
1287                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1288                 }
1289
1290                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1291                         status = nfs4_check_lease(clp);
1292                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1293                                 continue;
1294                         if (status < 0 && status != -NFS4ERR_CB_PATH_DOWN)
1295                                 goto out_error;
1296                 }
1297
1298                 /* Initialize or reset the session */
1299                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1300                    && nfs4_has_session(clp)) {
1301                         status = nfs4_reset_session(clp);
1302                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1303                                 continue;
1304                         if (status < 0)
1305                                 goto out_error;
1306                 }
1307
1308                 /* First recover reboot state... */
1309                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1310                         status = nfs4_do_reclaim(clp,
1311                                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1312                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1313                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1314                                 continue;
1315                         nfs4_state_end_reclaim_reboot(clp);
1316                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1317                                 continue;
1318                         if (status < 0)
1319                                 goto out_error;
1320                 }
1321
1322                 /* Now recover expired state... */
1323                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1324                         status = nfs4_do_reclaim(clp,
1325                                 nfs4_nograce_recovery_ops[clp->cl_minorversion]);
1326                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1327                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1328                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1329                                 continue;
1330                         if (status < 0)
1331                                 goto out_error;
1332                 }
1333
1334                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1335                         nfs_client_return_marked_delegations(clp);
1336                         continue;
1337                 }
1338
1339                 nfs4_clear_state_manager_bit(clp);
1340                 /* Did we race with an attempt to give us more work? */
1341                 if (clp->cl_state == 0)
1342                         break;
1343                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1344                         break;
1345         }
1346         return;
1347 out_error:
1348         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1349                         " with error %d\n", clp->cl_hostname, -status);
1350         nfs4_clear_state_manager_bit(clp);
1351 }
1352
1353 static int nfs4_run_state_manager(void *ptr)
1354 {
1355         struct nfs_client *clp = ptr;
1356
1357         allow_signal(SIGKILL);
1358         nfs4_state_manager(clp);
1359         nfs_put_client(clp);
1360         module_put_and_exit(0);
1361         return 0;
1362 }
1363
1364 /*
1365  * Local variables:
1366  *  c-basic-offset: 8
1367  * End:
1368  */