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         struct nfs4_setclientid_res clid;
  66         unsigned short port;
  67         int status;
  68
  69         port = nfs_callback_tcpport;
  70         if (clp->cl_addr.ss_family == AF_INET6)
  71                 port = nfs_callback_tcpport6;
  72
  73         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
  74         if (status != 0)
  75                 goto out;
  76         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
  77         if (status != 0)
  78                 goto out;
  79         clp->cl_clientid = clid.clientid;
  80         nfs4_schedule_state_renewal(clp);
  81 out:
  82         return status;
  83 }
  84
  85 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
  86 {
  87         struct rpc_cred *cred = NULL;
  88
  89         if (clp->cl_machine_cred != NULL)
  90                 cred = get_rpccred(clp->cl_machine_cred);
  91         return cred;
  92 }
  93
  94 static void nfs4_clear_machine_cred(struct nfs_client *clp)
  95 {
  96         struct rpc_cred *cred;
  97
  98         spin_lock(&clp->cl_lock);
  99         cred = clp->cl_machine_cred;
 100         clp->cl_machine_cred = NULL;
 101         spin_unlock(&clp->cl_lock);
 102         if (cred != NULL)
 103                 put_rpccred(cred);
 104 }
 105
 106 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 107 {
 108         struct nfs4_state_owner *sp;
 109         struct rb_node *pos;
 110         struct rpc_cred *cred = NULL;
 111
 112         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
 113                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 114                 if (list_empty(&sp->so_states))
 115                         continue;
 116                 cred = get_rpccred(sp->so_cred);
 117                 break;
 118         }
 119         return cred;
 120 }
 121
 122 #if defined(CONFIG_NFS_V4_1)
 123
 124 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 125 {
 126         int status;
 127         struct nfs_fsinfo fsinfo;
 128
 129         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 130         if (status == 0) {
 131                 /* Update lease time and schedule renewal */
 132                 spin_lock(&clp->cl_lock);
 133                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 134                 clp->cl_last_renewal = jiffies;
 135                 spin_unlock(&clp->cl_lock);
 136
 137                 nfs4_schedule_state_renewal(clp);
 138         }
 139
 140         return status;
 141 }
 142
 143 static void nfs4_end_drain_session(struct nfs_client *clp)
 144 {
 145         struct nfs4_session *ses = clp->cl_session;
 146         int max_slots;
 147
 148         if (test_and_clear_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state)) {
 149                 spin_lock(&ses->fc_slot_table.slot_tbl_lock);
 150                 max_slots = ses->fc_slot_table.max_slots;
 151                 while (max_slots--) {
 152                         struct rpc_task *task;
 153
 154                         task = rpc_wake_up_next(&ses->fc_slot_table.
 155                                                 slot_tbl_waitq);
 156                         if (!task)
 157                                 break;
 158                         rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED);
 159                 }
 160                 spin_unlock(&ses->fc_slot_table.slot_tbl_lock);
 161         }
 162 }
 163
 164 static int nfs4_begin_drain_session(struct nfs_client *clp)
 165 {
 166         struct nfs4_session *ses = clp->cl_session;
 167         struct nfs4_slot_table *tbl = &ses->fc_slot_table;
 168
 169         spin_lock(&tbl->slot_tbl_lock);
 170         set_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state);
 171         if (tbl->highest_used_slotid != -1) {
 172                 INIT_COMPLETION(ses->complete);
 173                 spin_unlock(&tbl->slot_tbl_lock);
 174                 return wait_for_completion_interruptible(&ses->complete);
 175         }
 176         spin_unlock(&tbl->slot_tbl_lock);
 177         return 0;
 178 }
 179
 180 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 181 {
 182         int status;
 183
 184         nfs4_begin_drain_session(clp);
 185         status = nfs4_proc_exchange_id(clp, cred);
 186         if (status != 0)
 187                 goto out;
 188         status = nfs4_proc_create_session(clp);
 189         if (status != 0)
 190                 goto out;
 191         nfs41_setup_state_renewal(clp);
 192         nfs_mark_client_ready(clp, NFS_CS_READY);
 193 out:
 194         return status;
 195 }
 196
 197 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 198 {
 199         struct rpc_cred *cred;
 200
 201         spin_lock(&clp->cl_lock);
 202         cred = nfs4_get_machine_cred_locked(clp);
 203         spin_unlock(&clp->cl_lock);
 204         return cred;
 205 }
 206
 207 #endif /* CONFIG_NFS_V4_1 */
 208
 209 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 210 {
 211         struct nfs4_state_owner *sp;
 212         struct rb_node *pos;
 213         struct rpc_cred *cred;
 214
 215         spin_lock(&clp->cl_lock);
 216         cred = nfs4_get_machine_cred_locked(clp);
 217         if (cred != NULL)
 218                 goto out;
 219         pos = rb_first(&clp->cl_state_owners);
 220         if (pos != NULL) {
 221                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 222                 cred = get_rpccred(sp->so_cred);
 223         }
 224 out:
 225         spin_unlock(&clp->cl_lock);
 226         return cred;
 227 }
 228
 229 static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
 230                 __u64 minval, int maxbits)
 231 {
 232         struct rb_node **p, *parent;
 233         struct nfs_unique_id *pos;
 234         __u64 mask = ~0ULL;
 235
 236         if (maxbits < 64)
 237                 mask = (1ULL << maxbits) - 1ULL;
 238
 239         /* Ensure distribution is more or less flat */
 240         get_random_bytes(&new->id, sizeof(new->id));
 241         new->id &= mask;
 242         if (new->id < minval)
 243                 new->id += minval;
 244 retry:
 245         p = &root->rb_node;
 246         parent = NULL;
 247
 248         while (*p != NULL) {
 249                 parent = *p;
 250                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 251
 252                 if (new->id < pos->id)
 253                         p = &(*p)->rb_left;
 254                 else if (new->id > pos->id)
 255                         p = &(*p)->rb_right;
 256                 else
 257                         goto id_exists;
 258         }
 259         rb_link_node(&new->rb_node, parent, p);
 260         rb_insert_color(&new->rb_node, root);
 261         return;
 262 id_exists:
 263         for (;;) {
 264                 new->id++;
 265                 if (new->id < minval || (new->id & mask) != new->id) {
 266                         new->id = minval;
 267                         break;
 268                 }
 269                 parent = rb_next(parent);
 270                 if (parent == NULL)
 271                         break;
 272                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 273                 if (new->id < pos->id)
 274                         break;
 275         }
 276         goto retry;
 277 }
 278
 279 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
 280 {
 281         rb_erase(&id->rb_node, root);
 282 }
 283
 284 static struct nfs4_state_owner *
 285 nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 286 {
 287         struct nfs_client *clp = server->nfs_client;
 288         struct rb_node **p = &clp->cl_state_owners.rb_node,
 289                        *parent = NULL;
 290         struct nfs4_state_owner *sp, *res = NULL;
 291
 292         while (*p != NULL) {
 293                 parent = *p;
 294                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 295
 296                 if (server < sp->so_server) {
 297                         p = &parent->rb_left;
 298                         continue;
 299                 }
 300                 if (server > sp->so_server) {
 301                         p = &parent->rb_right;
 302                         continue;
 303                 }
 304                 if (cred < sp->so_cred)
 305                         p = &parent->rb_left;
 306                 else if (cred > sp->so_cred)
 307                         p = &parent->rb_right;
 308                 else {
 309                         atomic_inc(&sp->so_count);
 310                         res = sp;
 311                         break;
 312                 }
 313         }
 314         return res;
 315 }
 316
 317 static struct nfs4_state_owner *
 318 nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
 319 {
 320         struct rb_node **p = &clp->cl_state_owners.rb_node,
 321                        *parent = NULL;
 322         struct nfs4_state_owner *sp;
 323
 324         while (*p != NULL) {
 325                 parent = *p;
 326                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 327
 328                 if (new->so_server < sp->so_server) {
 329                         p = &parent->rb_left;
 330                         continue;
 331                 }
 332                 if (new->so_server > sp->so_server) {
 333                         p = &parent->rb_right;
 334                         continue;
 335                 }
 336                 if (new->so_cred < sp->so_cred)
 337                         p = &parent->rb_left;
 338                 else if (new->so_cred > sp->so_cred)
 339                         p = &parent->rb_right;
 340                 else {
 341                         atomic_inc(&sp->so_count);
 342                         return sp;
 343                 }
 344         }
 345         nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
 346         rb_link_node(&new->so_client_node, parent, p);
 347         rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
 348         return new;
 349 }
 350
 351 static void
 352 nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
 353 {
 354         if (!RB_EMPTY_NODE(&sp->so_client_node))
 355                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 356         nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
 357 }
 358
 359 /*
 360  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 361  * create a new state_owner.
 362  *
 363  */
 364 static struct nfs4_state_owner *
 365 nfs4_alloc_state_owner(void)
 366 {
 367         struct nfs4_state_owner *sp;
 368
 369         sp = kzalloc(sizeof(*sp),GFP_KERNEL);
 370         if (!sp)
 371                 return NULL;
 372         spin_lock_init(&sp->so_lock);
 373         INIT_LIST_HEAD(&sp->so_states);
 374         INIT_LIST_HEAD(&sp->so_delegations);
 375         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 376         sp->so_seqid.sequence = &sp->so_sequence;
 377         spin_lock_init(&sp->so_sequence.lock);
 378         INIT_LIST_HEAD(&sp->so_sequence.list);
 379         atomic_set(&sp->so_count, 1);
 380         return sp;
 381 }
 382
 383 static void
 384 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 385 {
 386         if (!RB_EMPTY_NODE(&sp->so_client_node)) {
 387                 struct nfs_client *clp = sp->so_client;
 388
 389                 spin_lock(&clp->cl_lock);
 390                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 391                 RB_CLEAR_NODE(&sp->so_client_node);
 392                 spin_unlock(&clp->cl_lock);
 393         }
 394 }
 395
 396 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 397 {
 398         struct nfs_client *clp = server->nfs_client;
 399         struct nfs4_state_owner *sp, *new;
 400
 401         spin_lock(&clp->cl_lock);
 402         sp = nfs4_find_state_owner(server, cred);
 403         spin_unlock(&clp->cl_lock);
 404         if (sp != NULL)
 405                 return sp;
 406         new = nfs4_alloc_state_owner();
 407         if (new == NULL)
 408                 return NULL;
 409         new->so_client = clp;
 410         new->so_server = server;
 411         new->so_cred = cred;
 412         spin_lock(&clp->cl_lock);
 413         sp = nfs4_insert_state_owner(clp, new);
 414         spin_unlock(&clp->cl_lock);
 415         if (sp == new)
 416                 get_rpccred(cred);
 417         else {
 418                 rpc_destroy_wait_queue(&new->so_sequence.wait);
 419                 kfree(new);
 420         }
 421         return sp;
 422 }
 423
 424 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 425 {
 426         struct nfs_client *clp = sp->so_client;
 427         struct rpc_cred *cred = sp->so_cred;
 428
 429         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 430                 return;
 431         nfs4_remove_state_owner(clp, sp);
 432         spin_unlock(&clp->cl_lock);
 433         rpc_destroy_wait_queue(&sp->so_sequence.wait);
 434         put_rpccred(cred);
 435         kfree(sp);
 436 }
 437
 438 static struct nfs4_state *
 439 nfs4_alloc_open_state(void)
 440 {
 441         struct nfs4_state *state;
 442
 443         state = kzalloc(sizeof(*state), GFP_KERNEL);
 444         if (!state)
 445                 return NULL;
 446         atomic_set(&state->count, 1);
 447         INIT_LIST_HEAD(&state->lock_states);
 448         spin_lock_init(&state->state_lock);
 449         seqlock_init(&state->seqlock);
 450         return state;
 451 }
 452
 453 void
 454 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 455 {
 456         if (state->state == fmode)
 457                 return;
 458         /* NB! List reordering - see the reclaim code for why.  */
 459         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 460                 if (fmode & FMODE_WRITE)
 461                         list_move(&state->open_states, &state->owner->so_states);
 462                 else
 463                         list_move_tail(&state->open_states, &state->owner->so_states);
 464         }
 465         state->state = fmode;
 466 }
 467
 468 static struct nfs4_state *
 469 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 470 {
 471         struct nfs_inode *nfsi = NFS_I(inode);
 472         struct nfs4_state *state;
 473
 474         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 475                 if (state->owner != owner)
 476                         continue;
 477                 if (atomic_inc_not_zero(&state->count))
 478                         return state;
 479         }
 480         return NULL;
 481 }
 482
 483 static void
 484 nfs4_free_open_state(struct nfs4_state *state)
 485 {
 486         kfree(state);
 487 }
 488
 489 struct nfs4_state *
 490 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 491 {
 492         struct nfs4_state *state, *new;
 493         struct nfs_inode *nfsi = NFS_I(inode);
 494
 495         spin_lock(&inode->i_lock);
 496         state = __nfs4_find_state_byowner(inode, owner);
 497         spin_unlock(&inode->i_lock);
 498         if (state)
 499                 goto out;
 500         new = nfs4_alloc_open_state();
 501         spin_lock(&owner->so_lock);
 502         spin_lock(&inode->i_lock);
 503         state = __nfs4_find_state_byowner(inode, owner);
 504         if (state == NULL && new != NULL) {
 505                 state = new;
 506                 state->owner = owner;
 507                 atomic_inc(&owner->so_count);
 508                 list_add(&state->inode_states, &nfsi->open_states);
 509                 state->inode = igrab(inode);
 510                 spin_unlock(&inode->i_lock);
 511                 /* Note: The reclaim code dictates that we add stateless
 512                  * and read-only stateids to the end of the list */
 513                 list_add_tail(&state->open_states, &owner->so_states);
 514                 spin_unlock(&owner->so_lock);
 515         } else {
 516                 spin_unlock(&inode->i_lock);
 517                 spin_unlock(&owner->so_lock);
 518                 if (new)
 519                         nfs4_free_open_state(new);
 520         }
 521 out:
 522         return state;
 523 }
 524
 525 void nfs4_put_open_state(struct nfs4_state *state)
 526 {
 527         struct inode *inode = state->inode;
 528         struct nfs4_state_owner *owner = state->owner;
 529
 530         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 531                 return;
 532         spin_lock(&inode->i_lock);
 533         list_del(&state->inode_states);
 534         list_del(&state->open_states);
 535         spin_unlock(&inode->i_lock);
 536         spin_unlock(&owner->so_lock);
 537         iput(inode);
 538         nfs4_free_open_state(state);
 539         nfs4_put_state_owner(owner);
 540 }
 541
 542 /*
 543  * Close the current file.
 544  */
 545 static void __nfs4_close(struct path *path, struct nfs4_state *state, fmode_t fmode, int wait)
 546 {
 547         struct nfs4_state_owner *owner = state->owner;
 548         int call_close = 0;
 549         fmode_t newstate;
 550
 551         atomic_inc(&owner->so_count);
 552         /* Protect against nfs4_find_state() */
 553         spin_lock(&owner->so_lock);
 554         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 555                 case FMODE_READ:
 556                         state->n_rdonly--;
 557                         break;
 558                 case FMODE_WRITE:
 559                         state->n_wronly--;
 560                         break;
 561                 case FMODE_READ|FMODE_WRITE:
 562                         state->n_rdwr--;
 563         }
 564         newstate = FMODE_READ|FMODE_WRITE;
 565         if (state->n_rdwr == 0) {
 566                 if (state->n_rdonly == 0) {
 567                         newstate &= ~FMODE_READ;
 568                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 569                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 570                 }
 571                 if (state->n_wronly == 0) {
 572                         newstate &= ~FMODE_WRITE;
 573                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 574                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 575                 }
 576                 if (newstate == 0)
 577                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 578         }
 579         nfs4_state_set_mode_locked(state, newstate);
 580         spin_unlock(&owner->so_lock);
 581
 582         if (!call_close) {
 583                 nfs4_put_open_state(state);
 584                 nfs4_put_state_owner(owner);
 585         } else
 586                 nfs4_do_close(path, state, wait);
 587 }
 588
 589 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
 590 {
 591         __nfs4_close(path, state, fmode, 0);
 592 }
 593
 594 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
 595 {
 596         __nfs4_close(path, state, fmode, 1);
 597 }
 598
 599 /*
 600  * Search the state->lock_states for an existing lock_owner
 601  * that is compatible with current->files
 602  */
 603 static struct nfs4_lock_state *
 604 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 605 {
 606         struct nfs4_lock_state *pos;
 607         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 608                 if (pos->ls_owner != fl_owner)
 609                         continue;
 610                 atomic_inc(&pos->ls_count);
 611                 return pos;
 612         }
 613         return NULL;
 614 }
 615
 616 /*
 617  * Return a compatible lock_state. If no initialized lock_state structure
 618  * exists, return an uninitialized one.
 619  *
 620  */
 621 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 622 {
 623         struct nfs4_lock_state *lsp;
 624         struct nfs_client *clp = state->owner->so_client;
 625
 626         lsp = kzalloc(sizeof(*lsp), GFP_KERNEL);
 627         if (lsp == NULL)
 628                 return NULL;
 629         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 630         spin_lock_init(&lsp->ls_sequence.lock);
 631         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 632         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 633         atomic_set(&lsp->ls_count, 1);
 634         lsp->ls_state = state;
 635         lsp->ls_owner = fl_owner;
 636         spin_lock(&clp->cl_lock);
 637         nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
 638         spin_unlock(&clp->cl_lock);
 639         INIT_LIST_HEAD(&lsp->ls_locks);
 640         return lsp;
 641 }
 642
 643 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 644 {
 645         struct nfs_client *clp = lsp->ls_state->owner->so_client;
 646
 647         spin_lock(&clp->cl_lock);
 648         nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
 649         spin_unlock(&clp->cl_lock);
 650         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 651         kfree(lsp);
 652 }
 653
 654 /*
 655  * Return a compatible lock_state. If no initialized lock_state structure
 656  * exists, return an uninitialized one.
 657  *
 658  */
 659 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 660 {
 661         struct nfs4_lock_state *lsp, *new = NULL;
 662
 663         for(;;) {
 664                 spin_lock(&state->state_lock);
 665                 lsp = __nfs4_find_lock_state(state, owner);
 666                 if (lsp != NULL)
 667                         break;
 668                 if (new != NULL) {
 669                         list_add(&new->ls_locks, &state->lock_states);
 670                         set_bit(LK_STATE_IN_USE, &state->flags);
 671                         lsp = new;
 672                         new = NULL;
 673                         break;
 674                 }
 675                 spin_unlock(&state->state_lock);
 676                 new = nfs4_alloc_lock_state(state, owner);
 677                 if (new == NULL)
 678                         return NULL;
 679         }
 680         spin_unlock(&state->state_lock);
 681         if (new != NULL)
 682                 nfs4_free_lock_state(new);
 683         return lsp;
 684 }
 685
 686 /*
 687  * Release reference to lock_state, and free it if we see that
 688  * it is no longer in use
 689  */
 690 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 691 {
 692         struct nfs4_state *state;
 693
 694         if (lsp == NULL)
 695                 return;
 696         state = lsp->ls_state;
 697         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 698                 return;
 699         list_del(&lsp->ls_locks);
 700         if (list_empty(&state->lock_states))
 701                 clear_bit(LK_STATE_IN_USE, &state->flags);
 702         spin_unlock(&state->state_lock);
 703         nfs4_free_lock_state(lsp);
 704 }
 705
 706 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 707 {
 708         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 709
 710         dst->fl_u.nfs4_fl.owner = lsp;
 711         atomic_inc(&lsp->ls_count);
 712 }
 713
 714 static void nfs4_fl_release_lock(struct file_lock *fl)
 715 {
 716         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 717 }
 718
 719 static const struct file_lock_operations nfs4_fl_lock_ops = {
 720         .fl_copy_lock = nfs4_fl_copy_lock,
 721         .fl_release_private = nfs4_fl_release_lock,
 722 };
 723
 724 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 725 {
 726         struct nfs4_lock_state *lsp;
 727
 728         if (fl->fl_ops != NULL)
 729                 return 0;
 730         lsp = nfs4_get_lock_state(state, fl->fl_owner);
 731         if (lsp == NULL)
 732                 return -ENOMEM;
 733         fl->fl_u.nfs4_fl.owner = lsp;
 734         fl->fl_ops = &nfs4_fl_lock_ops;
 735         return 0;
 736 }
 737
 738 /*
 739  * Byte-range lock aware utility to initialize the stateid of read/write
 740  * requests.
 741  */
 742 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
 743 {
 744         struct nfs4_lock_state *lsp;
 745         int seq;
 746
 747         do {
 748                 seq = read_seqbegin(&state->seqlock);
 749                 memcpy(dst, &state->stateid, sizeof(*dst));
 750         } while (read_seqretry(&state->seqlock, seq));
 751         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 752                 return;
 753
 754         spin_lock(&state->state_lock);
 755         lsp = __nfs4_find_lock_state(state, fl_owner);
 756         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 757                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 758         spin_unlock(&state->state_lock);
 759         nfs4_put_lock_state(lsp);
 760 }
 761
 762 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
 763 {
 764         struct nfs_seqid *new;
 765
 766         new = kmalloc(sizeof(*new), GFP_KERNEL);
 767         if (new != NULL) {
 768                 new->sequence = counter;
 769                 INIT_LIST_HEAD(&new->list);
 770         }
 771         return new;
 772 }
 773
 774 void nfs_release_seqid(struct nfs_seqid *seqid)
 775 {
 776         if (!list_empty(&seqid->list)) {
 777                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 778
 779                 spin_lock(&sequence->lock);
 780                 list_del_init(&seqid->list);
 781                 spin_unlock(&sequence->lock);
 782                 rpc_wake_up(&sequence->wait);
 783         }
 784 }
 785
 786 void nfs_free_seqid(struct nfs_seqid *seqid)
 787 {
 788         nfs_release_seqid(seqid);
 789         kfree(seqid);
 790 }
 791
 792 /*
 793  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 794  * failed with a seqid incrementing error -
 795  * see comments nfs_fs.h:seqid_mutating_error()
 796  */
 797 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 798 {
 799         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 800         switch (status) {
 801                 case 0:
 802                         break;
 803                 case -NFS4ERR_BAD_SEQID:
 804                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
 805                                 return;
 806                         printk(KERN_WARNING "NFS: v4 server returned a bad"
 807                                         " sequence-id error on an"
 808                                         " unconfirmed sequence %p!\n",
 809                                         seqid->sequence);
 810                 case -NFS4ERR_STALE_CLIENTID:
 811                 case -NFS4ERR_STALE_STATEID:
 812                 case -NFS4ERR_BAD_STATEID:
 813                 case -NFS4ERR_BADXDR:
 814                 case -NFS4ERR_RESOURCE:
 815                 case -NFS4ERR_NOFILEHANDLE:
 816                         /* Non-seqid mutating errors */
 817                         return;
 818         };
 819         /*
 820          * Note: no locking needed as we are guaranteed to be first
 821          * on the sequence list
 822          */
 823         seqid->sequence->counter++;
 824 }
 825
 826 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
 827 {
 828         struct nfs4_state_owner *sp = container_of(seqid->sequence,
 829                                         struct nfs4_state_owner, so_seqid);
 830         struct nfs_server *server = sp->so_server;
 831
 832         if (status == -NFS4ERR_BAD_SEQID)
 833                 nfs4_drop_state_owner(sp);
 834         if (!nfs4_has_session(server->nfs_client))
 835                 nfs_increment_seqid(status, seqid);
 836 }
 837
 838 /*
 839  * Increment the seqid if the LOCK/LOCKU succeeded, or
 840  * failed with a seqid incrementing error -
 841  * see comments nfs_fs.h:seqid_mutating_error()
 842  */
 843 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
 844 {
 845         nfs_increment_seqid(status, seqid);
 846 }
 847
 848 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
 849 {
 850         struct rpc_sequence *sequence = seqid->sequence->sequence;
 851         int status = 0;
 852
 853         spin_lock(&sequence->lock);
 854         if (list_empty(&seqid->list))
 855                 list_add_tail(&seqid->list, &sequence->list);
 856         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
 857                 goto unlock;
 858         rpc_sleep_on(&sequence->wait, task, NULL);
 859         status = -EAGAIN;
 860 unlock:
 861         spin_unlock(&sequence->lock);
 862         return status;
 863 }
 864
 865 static int nfs4_run_state_manager(void *);
 866
 867 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
 868 {
 869         smp_mb__before_clear_bit();
 870         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
 871         smp_mb__after_clear_bit();
 872         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
 873         rpc_wake_up(&clp->cl_rpcwaitq);
 874 }
 875
 876 /*
 877  * Schedule the nfs_client asynchronous state management routine
 878  */
 879 void nfs4_schedule_state_manager(struct nfs_client *clp)
 880 {
 881         struct task_struct *task;
 882
 883         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
 884                 return;
 885         __module_get(THIS_MODULE);
 886         atomic_inc(&clp->cl_count);
 887         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
 888                                 rpc_peeraddr2str(clp->cl_rpcclient,
 889                                                         RPC_DISPLAY_ADDR));
 890         if (!IS_ERR(task))
 891                 return;
 892         nfs4_clear_state_manager_bit(clp);
 893         nfs_put_client(clp);
 894         module_put(THIS_MODULE);
 895 }
 896
 897 /*
 898  * Schedule a state recovery attempt
 899  */
 900 void nfs4_schedule_state_recovery(struct nfs_client *clp)
 901 {
 902         if (!clp)
 903                 return;
 904         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
 905                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
 906         nfs4_schedule_state_manager(clp);
 907 }
 908
 909 int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
 910 {
 911
 912         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 913         /* Don't recover state that expired before the reboot */
 914         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
 915                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 916                 return 0;
 917         }
 918         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
 919         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
 920         return 1;
 921 }
 922
 923 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
 924 {
 925         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
 926         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 927         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
 928         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
 929         return 1;
 930 }
 931
 932 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
 933 {
 934         struct inode *inode = state->inode;
 935         struct nfs_inode *nfsi = NFS_I(inode);
 936         struct file_lock *fl;
 937         int status = 0;
 938
 939         if (inode->i_flock == NULL)
 940                 return 0;
 941
 942         /* Guard against delegation returns and new lock/unlock calls */
 943         down_write(&nfsi->rwsem);
 944         /* Protect inode->i_flock using the BKL */
 945         lock_kernel();
 946         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
 947                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
 948                         continue;
 949                 if (nfs_file_open_context(fl->fl_file)->state != state)
 950                         continue;
 951                 unlock_kernel();
 952                 status = ops->recover_lock(state, fl);
 953                 switch (status) {
 954                         case 0:
 955                                 break;
 956                         case -ESTALE:
 957                         case -NFS4ERR_ADMIN_REVOKED:
 958                         case -NFS4ERR_STALE_STATEID:
 959                         case -NFS4ERR_BAD_STATEID:
 960                         case -NFS4ERR_EXPIRED:
 961                         case -NFS4ERR_NO_GRACE:
 962                         case -NFS4ERR_STALE_CLIENTID:
 963                         case -NFS4ERR_BADSESSION:
 964                         case -NFS4ERR_BADSLOT:
 965                         case -NFS4ERR_BAD_HIGH_SLOT:
 966                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 967                                 goto out;
 968                         default:
 969                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 970                                                 __func__, status);
 971                         case -ENOMEM:
 972                         case -NFS4ERR_DENIED:
 973                         case -NFS4ERR_RECLAIM_BAD:
 974                         case -NFS4ERR_RECLAIM_CONFLICT:
 975                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
 976                                 status = 0;
 977                 }
 978                 lock_kernel();
 979         }
 980         unlock_kernel();
 981 out:
 982         up_write(&nfsi->rwsem);
 983         return status;
 984 }
 985
 986 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
 987 {
 988         struct nfs4_state *state;
 989         struct nfs4_lock_state *lock;
 990         int status = 0;
 991
 992         /* Note: we rely on the sp->so_states list being ordered
 993          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
 994          * states first.
 995          * This is needed to ensure that the server won't give us any
 996          * read delegations that we have to return if, say, we are
 997          * recovering after a network partition or a reboot from a
 998          * server that doesn't support a grace period.
 999          */
1000 restart:
1001         spin_lock(&sp->so_lock);
1002         list_for_each_entry(state, &sp->so_states, open_states) {
1003                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1004                         continue;
1005                 if (state->state == 0)
1006                         continue;
1007                 atomic_inc(&state->count);
1008                 spin_unlock(&sp->so_lock);
1009                 status = ops->recover_open(sp, state);
1010                 if (status >= 0) {
1011                         status = nfs4_reclaim_locks(state, ops);
1012                         if (status >= 0) {
1013                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1014                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1015                                                 printk("%s: Lock reclaim failed!\n",
1016                                                         __func__);
1017                                 }
1018                                 nfs4_put_open_state(state);
1019                                 goto restart;
1020                         }
1021                 }
1022                 switch (status) {
1023                         default:
1024                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1025                                                 __func__, status);
1026                         case -ENOENT:
1027                         case -ENOMEM:
1028                         case -ESTALE:
1029                                 /*
1030                                  * Open state on this file cannot be recovered
1031                                  * All we can do is revert to using the zero stateid.
1032                                  */
1033                                 memset(state->stateid.data, 0,
1034                                         sizeof(state->stateid.data));
1035                                 /* Mark the file as being 'closed' */
1036                                 state->state = 0;
1037                                 break;
1038                         case -NFS4ERR_ADMIN_REVOKED:
1039                         case -NFS4ERR_STALE_STATEID:
1040                         case -NFS4ERR_BAD_STATEID:
1041                         case -NFS4ERR_RECLAIM_BAD:
1042                         case -NFS4ERR_RECLAIM_CONFLICT:
1043                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
1044                                 break;
1045                         case -NFS4ERR_EXPIRED:
1046                         case -NFS4ERR_NO_GRACE:
1047                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
1048                         case -NFS4ERR_STALE_CLIENTID:
1049                         case -NFS4ERR_BADSESSION:
1050                         case -NFS4ERR_BADSLOT:
1051                         case -NFS4ERR_BAD_HIGH_SLOT:
1052                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1053                                 goto out_err;
1054                 }
1055                 nfs4_put_open_state(state);
1056                 goto restart;
1057         }
1058         spin_unlock(&sp->so_lock);
1059         return 0;
1060 out_err:
1061         nfs4_put_open_state(state);
1062         return status;
1063 }
1064
1065 static void nfs4_clear_open_state(struct nfs4_state *state)
1066 {
1067         struct nfs4_lock_state *lock;
1068
1069         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1070         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1071         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1072         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1073         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1074                 lock->ls_seqid.flags = 0;
1075                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1076         }
1077 }
1078
1079 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1080 {
1081         struct nfs4_state_owner *sp;
1082         struct rb_node *pos;
1083         struct nfs4_state *state;
1084
1085         /* Reset all sequence ids to zero */
1086         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1087                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1088                 sp->so_seqid.flags = 0;
1089                 spin_lock(&sp->so_lock);
1090                 list_for_each_entry(state, &sp->so_states, open_states) {
1091                         if (mark_reclaim(clp, state))
1092                                 nfs4_clear_open_state(state);
1093                 }
1094                 spin_unlock(&sp->so_lock);
1095         }
1096 }
1097
1098 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1099 {
1100         /* Mark all delegations for reclaim */
1101         nfs_delegation_mark_reclaim(clp);
1102         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1103 }
1104
1105 static void nfs4_reclaim_complete(struct nfs_client *clp,
1106                                  const struct nfs4_state_recovery_ops *ops)
1107 {
1108         /* Notify the server we're done reclaiming our state */
1109         if (ops->reclaim_complete)
1110                 (void)ops->reclaim_complete(clp);
1111 }
1112
1113 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1114 {
1115         struct nfs4_state_owner *sp;
1116         struct rb_node *pos;
1117         struct nfs4_state *state;
1118
1119         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1120                 return;
1121
1122         nfs4_reclaim_complete(clp,
1123                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1124
1125         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1126                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1127                 spin_lock(&sp->so_lock);
1128                 list_for_each_entry(state, &sp->so_states, open_states) {
1129                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
1130                                 continue;
1131                         nfs4_state_mark_reclaim_nograce(clp, state);
1132                 }
1133                 spin_unlock(&sp->so_lock);
1134         }
1135
1136         nfs_delegation_reap_unclaimed(clp);
1137 }
1138
1139 static void nfs_delegation_clear_all(struct nfs_client *clp)
1140 {
1141         nfs_delegation_mark_reclaim(clp);
1142         nfs_delegation_reap_unclaimed(clp);
1143 }
1144
1145 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1146 {
1147         nfs_delegation_clear_all(clp);
1148         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1149 }
1150
1151 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1152 {
1153         switch (error) {
1154                 case -NFS4ERR_CB_PATH_DOWN:
1155                         nfs_handle_cb_pathdown(clp);
1156                         return 0;
1157                 case -NFS4ERR_NO_GRACE:
1158                         nfs4_state_end_reclaim_reboot(clp);
1159                         return 0;
1160                 case -NFS4ERR_STALE_CLIENTID:
1161                 case -NFS4ERR_LEASE_MOVED:
1162                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1163                         nfs4_state_end_reclaim_reboot(clp);
1164                         nfs4_state_start_reclaim_reboot(clp);
1165                         break;
1166                 case -NFS4ERR_EXPIRED:
1167                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1168                         nfs4_state_start_reclaim_nograce(clp);
1169                         break;
1170                 case -NFS4ERR_BADSESSION:
1171                 case -NFS4ERR_BADSLOT:
1172                 case -NFS4ERR_BAD_HIGH_SLOT:
1173                 case -NFS4ERR_DEADSESSION:
1174                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1175                 case -NFS4ERR_SEQ_FALSE_RETRY:
1176                 case -NFS4ERR_SEQ_MISORDERED:
1177                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1178                         /* Zero session reset errors */
1179                         return 0;
1180         }
1181         return error;
1182 }
1183
1184 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1185 {
1186         struct rb_node *pos;
1187         int status = 0;
1188
1189 restart:
1190         spin_lock(&clp->cl_lock);
1191         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1192                 struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1193                 if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
1194                         continue;
1195                 atomic_inc(&sp->so_count);
1196                 spin_unlock(&clp->cl_lock);
1197                 status = nfs4_reclaim_open_state(sp, ops);
1198                 if (status < 0) {
1199                         set_bit(ops->owner_flag_bit, &sp->so_flags);
1200                         nfs4_put_state_owner(sp);
1201                         return nfs4_recovery_handle_error(clp, status);
1202                 }
1203                 nfs4_put_state_owner(sp);
1204                 goto restart;
1205         }
1206         spin_unlock(&clp->cl_lock);
1207         return status;
1208 }
1209
1210 static int nfs4_check_lease(struct nfs_client *clp)
1211 {
1212         struct rpc_cred *cred;
1213         struct nfs4_state_maintenance_ops *ops =
1214                 nfs4_state_renewal_ops[clp->cl_minorversion];
1215         int status = -NFS4ERR_EXPIRED;
1216
1217         /* Is the client already known to have an expired lease? */
1218         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1219                 return 0;
1220         spin_lock(&clp->cl_lock);
1221         cred = ops->get_state_renewal_cred_locked(clp);
1222         spin_unlock(&clp->cl_lock);
1223         if (cred == NULL) {
1224                 cred = nfs4_get_setclientid_cred(clp);
1225                 if (cred == NULL)
1226                         goto out;
1227         }
1228         status = ops->renew_lease(clp, cred);
1229         put_rpccred(cred);
1230 out:
1231         return nfs4_recovery_handle_error(clp, status);
1232 }
1233
1234 static int nfs4_reclaim_lease(struct nfs_client *clp)
1235 {
1236         struct rpc_cred *cred;
1237         struct nfs4_state_recovery_ops *ops =
1238                 nfs4_reboot_recovery_ops[clp->cl_minorversion];
1239         int status = -ENOENT;
1240
1241         cred = ops->get_clid_cred(clp);
1242         if (cred != NULL) {
1243                 status = ops->establish_clid(clp, cred);
1244                 put_rpccred(cred);
1245                 /* Handle case where the user hasn't set up machine creds */
1246                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1247                         nfs4_clear_machine_cred(clp);
1248                         status = -EAGAIN;
1249                 }
1250                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1251                         status = -EPROTONOSUPPORT;
1252         }
1253         return status;
1254 }
1255
1256 #ifdef CONFIG_NFS_V4_1
1257 void nfs41_handle_recall_slot(struct nfs_client *clp)
1258 {
1259         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1260         nfs4_schedule_state_recovery(clp);
1261 }
1262
1263 static void nfs4_reset_all_state(struct nfs_client *clp)
1264 {
1265         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1266                 clp->cl_boot_time = CURRENT_TIME;
1267                 nfs4_state_start_reclaim_nograce(clp);
1268                 nfs4_schedule_state_recovery(clp);
1269         }
1270 }
1271
1272 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1273 {
1274         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1275                 nfs4_state_start_reclaim_reboot(clp);
1276                 nfs4_schedule_state_recovery(clp);
1277         }
1278 }
1279
1280 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1281 {
1282         /* Temporary */
1283         nfs4_reset_all_state(clp);
1284 }
1285
1286 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1287 {
1288         /* This will need to handle layouts too */
1289         nfs_expire_all_delegations(clp);
1290 }
1291
1292 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1293 {
1294         nfs_expire_all_delegations(clp);
1295         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1296                 nfs4_schedule_state_recovery(clp);
1297 }
1298
1299 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1300 {
1301         if (!flags)
1302                 return;
1303         else if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1304                 nfs41_handle_server_reboot(clp);
1305         else if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1306                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1307                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1308                             SEQ4_STATUS_LEASE_MOVED))
1309                 nfs41_handle_state_revoked(clp);
1310         else if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1311                 nfs41_handle_recallable_state_revoked(clp);
1312         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1313                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1314                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1315                 nfs41_handle_cb_path_down(clp);
1316 }
1317
1318 static int nfs4_reset_session(struct nfs_client *clp)
1319 {
1320         int status;
1321
1322         nfs4_begin_drain_session(clp);
1323         status = nfs4_proc_destroy_session(clp->cl_session);
1324         if (status && status != -NFS4ERR_BADSESSION &&
1325             status != -NFS4ERR_DEADSESSION) {
1326                 status = nfs4_recovery_handle_error(clp, status);
1327                 goto out;
1328         }
1329
1330         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1331         status = nfs4_proc_create_session(clp);
1332         if (status) {
1333                 status = nfs4_recovery_handle_error(clp, status);
1334                 goto out;
1335         }
1336         /* create_session negotiated new slot table */
1337         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1338
1339          /* Let the state manager reestablish state */
1340         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1341                 nfs41_setup_state_renewal(clp);
1342 out:
1343         return status;
1344 }
1345
1346 static int nfs4_recall_slot(struct nfs_client *clp)
1347 {
1348         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1349         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1350         struct nfs4_slot *new, *old;
1351         int i;
1352
1353         nfs4_begin_drain_session(clp);
1354         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1355                       GFP_KERNEL);
1356         if (!new)
1357                 return -ENOMEM;
1358
1359         spin_lock(&fc_tbl->slot_tbl_lock);
1360         for (i = 0; i < fc_tbl->target_max_slots; i++)
1361                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1362         old = fc_tbl->slots;
1363         fc_tbl->slots = new;
1364         fc_tbl->max_slots = fc_tbl->target_max_slots;
1365         fc_tbl->target_max_slots = 0;
1366         fc_attrs->max_reqs = fc_tbl->max_slots;
1367         spin_unlock(&fc_tbl->slot_tbl_lock);
1368
1369         kfree(old);
1370         nfs4_end_drain_session(clp);
1371         return 0;
1372 }
1373
1374 #else /* CONFIG_NFS_V4_1 */
1375 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1376 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1377 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1378 #endif /* CONFIG_NFS_V4_1 */
1379
1380 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1381  * on EXCHANGE_ID for v4.1
1382  */
1383 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1384 {
1385         if (nfs4_has_session(clp)) {
1386                 switch (status) {
1387                 case -NFS4ERR_DELAY:
1388                 case -NFS4ERR_CLID_INUSE:
1389                 case -EAGAIN:
1390                 case -EKEYEXPIRED:
1391                         break;
1392
1393                 case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1394                                          * in nfs4_exchange_id */
1395                 default:
1396                         return;
1397                 }
1398         }
1399         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1400 }
1401
1402 static void nfs4_state_manager(struct nfs_client *clp)
1403 {
1404         int status = 0;
1405
1406         /* Ensure exclusive access to NFSv4 state */
1407         for(;;) {
1408                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1409                         /* We're going to have to re-establish a clientid */
1410                         status = nfs4_reclaim_lease(clp);
1411                         if (status) {
1412                                 nfs4_set_lease_expired(clp, status);
1413                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1414                                                         &clp->cl_state))
1415                                         continue;
1416                                 if (clp->cl_cons_state ==
1417                                                         NFS_CS_SESSION_INITING)
1418                                         nfs_mark_client_ready(clp, status);
1419                                 goto out_error;
1420                         }
1421                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1422                         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1423                 }
1424
1425                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1426                         status = nfs4_check_lease(clp);
1427                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1428                                 continue;
1429                         if (status < 0 && status != -NFS4ERR_CB_PATH_DOWN)
1430                                 goto out_error;
1431                 }
1432
1433                 /* Initialize or reset the session */
1434                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1435                    && nfs4_has_session(clp)) {
1436                         status = nfs4_reset_session(clp);
1437                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1438                                 continue;
1439                         if (status < 0)
1440                                 goto out_error;
1441                 }
1442
1443                 /* First recover reboot state... */
1444                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1445                         status = nfs4_do_reclaim(clp,
1446                                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1447                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1448                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1449                                 continue;
1450                         nfs4_state_end_reclaim_reboot(clp);
1451                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1452                                 continue;
1453                         if (status < 0)
1454                                 goto out_error;
1455                 }
1456
1457                 /* Now recover expired state... */
1458                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1459                         status = nfs4_do_reclaim(clp,
1460                                 nfs4_nograce_recovery_ops[clp->cl_minorversion]);
1461                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1462                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1463                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1464                                 continue;
1465                         if (status < 0)
1466                                 goto out_error;
1467                 }
1468
1469                 nfs4_end_drain_session(clp);
1470                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1471                         nfs_client_return_marked_delegations(clp);
1472                         continue;
1473                 }
1474                 /* Recall session slots */
1475                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1476                    && nfs4_has_session(clp)) {
1477                         status = nfs4_recall_slot(clp);
1478                         if (status < 0)
1479                                 goto out_error;
1480                         continue;
1481                 }
1482
1483
1484                 nfs4_clear_state_manager_bit(clp);
1485                 /* Did we race with an attempt to give us more work? */
1486                 if (clp->cl_state == 0)
1487                         break;
1488                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1489                         break;
1490         }
1491         return;
1492 out_error:
1493         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1494                         " with error %d\n", clp->cl_hostname, -status);
1495         nfs4_end_drain_session(clp);
1496         nfs4_clear_state_manager_bit(clp);
1497 }
1498
1499 static int nfs4_run_state_manager(void *ptr)
1500 {
1501         struct nfs_client *clp = ptr;
1502
1503         allow_signal(SIGKILL);
1504         nfs4_state_manager(clp);
1505         nfs_put_client(clp);
1506         module_put_and_exit(0);
1507         return 0;
1508 }
1509
1510 /*
1511  * Local variables:
1512  *  c-basic-offset: 8
1513  * End:
1514  */