fs/nfs/nfs4state.c

   1 /*
   2  *  fs/nfs/nfs4state.c
   3  *
   4  *  Client-side XDR for NFSv4.
   5  *
   6  *  Copyright (c) 2002 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Kendrick Smith <kmsmith@umich.edu>
  10  *
  11  *  Redistribution and use in source and binary forms, with or without
  12  *  modification, are permitted provided that the following conditions
  13  *  are met:
  14  *
  15  *  1. Redistributions of source code must retain the above copyright
  16  *     notice, this list of conditions and the following disclaimer.
  17  *  2. Redistributions in binary form must reproduce the above copyright
  18  *     notice, this list of conditions and the following disclaimer in the
  19  *     documentation and/or other materials provided with the distribution.
  20  *  3. Neither the name of the University nor the names of its
  21  *     contributors may be used to endorse or promote products derived
  22  *     from this software without specific prior written permission.
  23  *
  24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  * Implementation of the NFSv4 state model.  For the time being,
  37  * this is minimal, but will be made much more complex in a
  38  * subsequent patch.
  39  */
  40
  41 #include <linux/kernel.h>
  42 #include <linux/slab.h>
  43 #include <linux/fs.h>
  44 #include <linux/nfs_fs.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/kthread.h>
  47 #include <linux/module.h>
  48 #include <linux/random.h>
  49 #include <linux/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 (ses == NULL)
 149                 return;
 150         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
 151                 spin_lock(&ses->fc_slot_table.slot_tbl_lock);
 152                 max_slots = ses->fc_slot_table.max_slots;
 153                 while (max_slots--) {
 154                         struct rpc_task *task;
 155
 156                         task = rpc_wake_up_next(&ses->fc_slot_table.
 157                                                 slot_tbl_waitq);
 158                         if (!task)
 159                                 break;
 160                         rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED);
 161                 }
 162                 spin_unlock(&ses->fc_slot_table.slot_tbl_lock);
 163         }
 164 }
 165
 166 static int nfs4_begin_drain_session(struct nfs_client *clp)
 167 {
 168         struct nfs4_session *ses = clp->cl_session;
 169         struct nfs4_slot_table *tbl = &ses->fc_slot_table;
 170
 171         spin_lock(&tbl->slot_tbl_lock);
 172         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
 173         if (tbl->highest_used_slotid != -1) {
 174                 INIT_COMPLETION(ses->complete);
 175                 spin_unlock(&tbl->slot_tbl_lock);
 176                 return wait_for_completion_interruptible(&ses->complete);
 177         }
 178         spin_unlock(&tbl->slot_tbl_lock);
 179         return 0;
 180 }
 181
 182 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 183 {
 184         int status;
 185
 186         nfs4_begin_drain_session(clp);
 187         status = nfs4_proc_exchange_id(clp, cred);
 188         if (status != 0)
 189                 goto out;
 190         status = nfs4_proc_create_session(clp);
 191         if (status != 0)
 192                 goto out;
 193         nfs41_setup_state_renewal(clp);
 194         nfs_mark_client_ready(clp, NFS_CS_READY);
 195 out:
 196         return status;
 197 }
 198
 199 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 200 {
 201         struct rpc_cred *cred;
 202
 203         spin_lock(&clp->cl_lock);
 204         cred = nfs4_get_machine_cred_locked(clp);
 205         spin_unlock(&clp->cl_lock);
 206         return cred;
 207 }
 208
 209 #endif /* CONFIG_NFS_V4_1 */
 210
 211 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 212 {
 213         struct nfs4_state_owner *sp;
 214         struct rb_node *pos;
 215         struct rpc_cred *cred;
 216
 217         spin_lock(&clp->cl_lock);
 218         cred = nfs4_get_machine_cred_locked(clp);
 219         if (cred != NULL)
 220                 goto out;
 221         pos = rb_first(&clp->cl_state_owners);
 222         if (pos != NULL) {
 223                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 224                 cred = get_rpccred(sp->so_cred);
 225         }
 226 out:
 227         spin_unlock(&clp->cl_lock);
 228         return cred;
 229 }
 230
 231 static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
 232                 __u64 minval, int maxbits)
 233 {
 234         struct rb_node **p, *parent;
 235         struct nfs_unique_id *pos;
 236         __u64 mask = ~0ULL;
 237
 238         if (maxbits < 64)
 239                 mask = (1ULL << maxbits) - 1ULL;
 240
 241         /* Ensure distribution is more or less flat */
 242         get_random_bytes(&new->id, sizeof(new->id));
 243         new->id &= mask;
 244         if (new->id < minval)
 245                 new->id += minval;
 246 retry:
 247         p = &root->rb_node;
 248         parent = NULL;
 249
 250         while (*p != NULL) {
 251                 parent = *p;
 252                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 253
 254                 if (new->id < pos->id)
 255                         p = &(*p)->rb_left;
 256                 else if (new->id > pos->id)
 257                         p = &(*p)->rb_right;
 258                 else
 259                         goto id_exists;
 260         }
 261         rb_link_node(&new->rb_node, parent, p);
 262         rb_insert_color(&new->rb_node, root);
 263         return;
 264 id_exists:
 265         for (;;) {
 266                 new->id++;
 267                 if (new->id < minval || (new->id & mask) != new->id) {
 268                         new->id = minval;
 269                         break;
 270                 }
 271                 parent = rb_next(parent);
 272                 if (parent == NULL)
 273                         break;
 274                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 275                 if (new->id < pos->id)
 276                         break;
 277         }
 278         goto retry;
 279 }
 280
 281 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
 282 {
 283         rb_erase(&id->rb_node, root);
 284 }
 285
 286 static struct nfs4_state_owner *
 287 nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 288 {
 289         struct nfs_client *clp = server->nfs_client;
 290         struct rb_node **p = &clp->cl_state_owners.rb_node,
 291                        *parent = NULL;
 292         struct nfs4_state_owner *sp, *res = NULL;
 293
 294         while (*p != NULL) {
 295                 parent = *p;
 296                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 297
 298                 if (server < sp->so_server) {
 299                         p = &parent->rb_left;
 300                         continue;
 301                 }
 302                 if (server > sp->so_server) {
 303                         p = &parent->rb_right;
 304                         continue;
 305                 }
 306                 if (cred < sp->so_cred)
 307                         p = &parent->rb_left;
 308                 else if (cred > sp->so_cred)
 309                         p = &parent->rb_right;
 310                 else {
 311                         atomic_inc(&sp->so_count);
 312                         res = sp;
 313                         break;
 314                 }
 315         }
 316         return res;
 317 }
 318
 319 static struct nfs4_state_owner *
 320 nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
 321 {
 322         struct rb_node **p = &clp->cl_state_owners.rb_node,
 323                        *parent = NULL;
 324         struct nfs4_state_owner *sp;
 325
 326         while (*p != NULL) {
 327                 parent = *p;
 328                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 329
 330                 if (new->so_server < sp->so_server) {
 331                         p = &parent->rb_left;
 332                         continue;
 333                 }
 334                 if (new->so_server > sp->so_server) {
 335                         p = &parent->rb_right;
 336                         continue;
 337                 }
 338                 if (new->so_cred < sp->so_cred)
 339                         p = &parent->rb_left;
 340                 else if (new->so_cred > sp->so_cred)
 341                         p = &parent->rb_right;
 342                 else {
 343                         atomic_inc(&sp->so_count);
 344                         return sp;
 345                 }
 346         }
 347         nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
 348         rb_link_node(&new->so_client_node, parent, p);
 349         rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
 350         return new;
 351 }
 352
 353 static void
 354 nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
 355 {
 356         if (!RB_EMPTY_NODE(&sp->so_client_node))
 357                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 358         nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
 359 }
 360
 361 /*
 362  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 363  * create a new state_owner.
 364  *
 365  */
 366 static struct nfs4_state_owner *
 367 nfs4_alloc_state_owner(void)
 368 {
 369         struct nfs4_state_owner *sp;
 370
 371         sp = kzalloc(sizeof(*sp),GFP_NOFS);
 372         if (!sp)
 373                 return NULL;
 374         spin_lock_init(&sp->so_lock);
 375         INIT_LIST_HEAD(&sp->so_states);
 376         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 377         sp->so_seqid.sequence = &sp->so_sequence;
 378         spin_lock_init(&sp->so_sequence.lock);
 379         INIT_LIST_HEAD(&sp->so_sequence.list);
 380         atomic_set(&sp->so_count, 1);
 381         return sp;
 382 }
 383
 384 static void
 385 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 386 {
 387         if (!RB_EMPTY_NODE(&sp->so_client_node)) {
 388                 struct nfs_client *clp = sp->so_server->nfs_client;
 389
 390                 spin_lock(&clp->cl_lock);
 391                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 392                 RB_CLEAR_NODE(&sp->so_client_node);
 393                 spin_unlock(&clp->cl_lock);
 394         }
 395 }
 396
 397 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 398 {
 399         struct nfs_client *clp = server->nfs_client;
 400         struct nfs4_state_owner *sp, *new;
 401
 402         spin_lock(&clp->cl_lock);
 403         sp = nfs4_find_state_owner(server, cred);
 404         spin_unlock(&clp->cl_lock);
 405         if (sp != NULL)
 406                 return sp;
 407         new = nfs4_alloc_state_owner();
 408         if (new == NULL)
 409                 return NULL;
 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_server->nfs_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_NOFS);
 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,
 546                 fmode_t fmode, gfp_t gfp_mask, int wait)
 547 {
 548         struct nfs4_state_owner *owner = state->owner;
 549         int call_close = 0;
 550         fmode_t newstate;
 551
 552         atomic_inc(&owner->so_count);
 553         /* Protect against nfs4_find_state() */
 554         spin_lock(&owner->so_lock);
 555         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 556                 case FMODE_READ:
 557                         state->n_rdonly--;
 558                         break;
 559                 case FMODE_WRITE:
 560                         state->n_wronly--;
 561                         break;
 562                 case FMODE_READ|FMODE_WRITE:
 563                         state->n_rdwr--;
 564         }
 565         newstate = FMODE_READ|FMODE_WRITE;
 566         if (state->n_rdwr == 0) {
 567                 if (state->n_rdonly == 0) {
 568                         newstate &= ~FMODE_READ;
 569                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 570                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 571                 }
 572                 if (state->n_wronly == 0) {
 573                         newstate &= ~FMODE_WRITE;
 574                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 575                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 576                 }
 577                 if (newstate == 0)
 578                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 579         }
 580         nfs4_state_set_mode_locked(state, newstate);
 581         spin_unlock(&owner->so_lock);
 582
 583         if (!call_close) {
 584                 nfs4_put_open_state(state);
 585                 nfs4_put_state_owner(owner);
 586         } else
 587                 nfs4_do_close(path, state, gfp_mask, wait);
 588 }
 589
 590 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
 591 {
 592         __nfs4_close(path, state, fmode, GFP_NOFS, 0);
 593 }
 594
 595 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
 596 {
 597         __nfs4_close(path, state, fmode, GFP_KERNEL, 1);
 598 }
 599
 600 /*
 601  * Search the state->lock_states for an existing lock_owner
 602  * that is compatible with current->files
 603  */
 604 static struct nfs4_lock_state *
 605 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 606 {
 607         struct nfs4_lock_state *pos;
 608         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 609                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
 610                         continue;
 611                 switch (pos->ls_owner.lo_type) {
 612                 case NFS4_POSIX_LOCK_TYPE:
 613                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
 614                                 continue;
 615                         break;
 616                 case NFS4_FLOCK_LOCK_TYPE:
 617                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
 618                                 continue;
 619                 }
 620                 atomic_inc(&pos->ls_count);
 621                 return pos;
 622         }
 623         return NULL;
 624 }
 625
 626 /*
 627  * Return a compatible lock_state. If no initialized lock_state structure
 628  * exists, return an uninitialized one.
 629  *
 630  */
 631 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 632 {
 633         struct nfs4_lock_state *lsp;
 634         struct nfs_client *clp = state->owner->so_server->nfs_client;
 635
 636         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 637         if (lsp == NULL)
 638                 return NULL;
 639         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 640         spin_lock_init(&lsp->ls_sequence.lock);
 641         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 642         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 643         atomic_set(&lsp->ls_count, 1);
 644         lsp->ls_state = state;
 645         lsp->ls_owner.lo_type = type;
 646         switch (lsp->ls_owner.lo_type) {
 647         case NFS4_FLOCK_LOCK_TYPE:
 648                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
 649                 break;
 650         case NFS4_POSIX_LOCK_TYPE:
 651                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
 652                 break;
 653         default:
 654                 kfree(lsp);
 655                 return NULL;
 656         }
 657         spin_lock(&clp->cl_lock);
 658         nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
 659         spin_unlock(&clp->cl_lock);
 660         INIT_LIST_HEAD(&lsp->ls_locks);
 661         return lsp;
 662 }
 663
 664 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 665 {
 666         struct nfs_client *clp = lsp->ls_state->owner->so_server->nfs_client;
 667
 668         spin_lock(&clp->cl_lock);
 669         nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
 670         spin_unlock(&clp->cl_lock);
 671         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 672         kfree(lsp);
 673 }
 674
 675 /*
 676  * Return a compatible lock_state. If no initialized lock_state structure
 677  * exists, return an uninitialized one.
 678  *
 679  */
 680 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
 681 {
 682         struct nfs4_lock_state *lsp, *new = NULL;
 683
 684         for(;;) {
 685                 spin_lock(&state->state_lock);
 686                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
 687                 if (lsp != NULL)
 688                         break;
 689                 if (new != NULL) {
 690                         list_add(&new->ls_locks, &state->lock_states);
 691                         set_bit(LK_STATE_IN_USE, &state->flags);
 692                         lsp = new;
 693                         new = NULL;
 694                         break;
 695                 }
 696                 spin_unlock(&state->state_lock);
 697                 new = nfs4_alloc_lock_state(state, owner, pid, type);
 698                 if (new == NULL)
 699                         return NULL;
 700         }
 701         spin_unlock(&state->state_lock);
 702         if (new != NULL)
 703                 nfs4_free_lock_state(new);
 704         return lsp;
 705 }
 706
 707 /*
 708  * Release reference to lock_state, and free it if we see that
 709  * it is no longer in use
 710  */
 711 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 712 {
 713         struct nfs4_state *state;
 714
 715         if (lsp == NULL)
 716                 return;
 717         state = lsp->ls_state;
 718         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 719                 return;
 720         list_del(&lsp->ls_locks);
 721         if (list_empty(&state->lock_states))
 722                 clear_bit(LK_STATE_IN_USE, &state->flags);
 723         spin_unlock(&state->state_lock);
 724         if (lsp->ls_flags & NFS_LOCK_INITIALIZED)
 725                 nfs4_release_lockowner(lsp);
 726         nfs4_free_lock_state(lsp);
 727 }
 728
 729 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 730 {
 731         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 732
 733         dst->fl_u.nfs4_fl.owner = lsp;
 734         atomic_inc(&lsp->ls_count);
 735 }
 736
 737 static void nfs4_fl_release_lock(struct file_lock *fl)
 738 {
 739         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 740 }
 741
 742 static const struct file_lock_operations nfs4_fl_lock_ops = {
 743         .fl_copy_lock = nfs4_fl_copy_lock,
 744         .fl_release_private = nfs4_fl_release_lock,
 745 };
 746
 747 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 748 {
 749         struct nfs4_lock_state *lsp;
 750
 751         if (fl->fl_ops != NULL)
 752                 return 0;
 753         if (fl->fl_flags & FL_POSIX)
 754                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
 755         else if (fl->fl_flags & FL_FLOCK)
 756                 lsp = nfs4_get_lock_state(state, 0, fl->fl_pid, NFS4_FLOCK_LOCK_TYPE);
 757         else
 758                 return -EINVAL;
 759         if (lsp == NULL)
 760                 return -ENOMEM;
 761         fl->fl_u.nfs4_fl.owner = lsp;
 762         fl->fl_ops = &nfs4_fl_lock_ops;
 763         return 0;
 764 }
 765
 766 /*
 767  * Byte-range lock aware utility to initialize the stateid of read/write
 768  * requests.
 769  */
 770 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid)
 771 {
 772         struct nfs4_lock_state *lsp;
 773         int seq;
 774
 775         do {
 776                 seq = read_seqbegin(&state->seqlock);
 777                 memcpy(dst, &state->stateid, sizeof(*dst));
 778         } while (read_seqretry(&state->seqlock, seq));
 779         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 780                 return;
 781
 782         spin_lock(&state->state_lock);
 783         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
 784         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 785                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 786         spin_unlock(&state->state_lock);
 787         nfs4_put_lock_state(lsp);
 788 }
 789
 790 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
 791 {
 792         struct nfs_seqid *new;
 793
 794         new = kmalloc(sizeof(*new), gfp_mask);
 795         if (new != NULL) {
 796                 new->sequence = counter;
 797                 INIT_LIST_HEAD(&new->list);
 798         }
 799         return new;
 800 }
 801
 802 void nfs_release_seqid(struct nfs_seqid *seqid)
 803 {
 804         if (!list_empty(&seqid->list)) {
 805                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 806
 807                 spin_lock(&sequence->lock);
 808                 list_del_init(&seqid->list);
 809                 spin_unlock(&sequence->lock);
 810                 rpc_wake_up(&sequence->wait);
 811         }
 812 }
 813
 814 void nfs_free_seqid(struct nfs_seqid *seqid)
 815 {
 816         nfs_release_seqid(seqid);
 817         kfree(seqid);
 818 }
 819
 820 /*
 821  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 822  * failed with a seqid incrementing error -
 823  * see comments nfs_fs.h:seqid_mutating_error()
 824  */
 825 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 826 {
 827         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 828         switch (status) {
 829                 case 0:
 830                         break;
 831                 case -NFS4ERR_BAD_SEQID:
 832                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
 833                                 return;
 834                         printk(KERN_WARNING "NFS: v4 server returned a bad"
 835                                         " sequence-id error on an"
 836                                         " unconfirmed sequence %p!\n",
 837                                         seqid->sequence);
 838                 case -NFS4ERR_STALE_CLIENTID:
 839                 case -NFS4ERR_STALE_STATEID:
 840                 case -NFS4ERR_BAD_STATEID:
 841                 case -NFS4ERR_BADXDR:
 842                 case -NFS4ERR_RESOURCE:
 843                 case -NFS4ERR_NOFILEHANDLE:
 844                         /* Non-seqid mutating errors */
 845                         return;
 846         };
 847         /*
 848          * Note: no locking needed as we are guaranteed to be first
 849          * on the sequence list
 850          */
 851         seqid->sequence->counter++;
 852 }
 853
 854 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
 855 {
 856         struct nfs4_state_owner *sp = container_of(seqid->sequence,
 857                                         struct nfs4_state_owner, so_seqid);
 858         struct nfs_server *server = sp->so_server;
 859
 860         if (status == -NFS4ERR_BAD_SEQID)
 861                 nfs4_drop_state_owner(sp);
 862         if (!nfs4_has_session(server->nfs_client))
 863                 nfs_increment_seqid(status, seqid);
 864 }
 865
 866 /*
 867  * Increment the seqid if the LOCK/LOCKU succeeded, or
 868  * failed with a seqid incrementing error -
 869  * see comments nfs_fs.h:seqid_mutating_error()
 870  */
 871 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
 872 {
 873         nfs_increment_seqid(status, seqid);
 874 }
 875
 876 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
 877 {
 878         struct rpc_sequence *sequence = seqid->sequence->sequence;
 879         int status = 0;
 880
 881         spin_lock(&sequence->lock);
 882         if (list_empty(&seqid->list))
 883                 list_add_tail(&seqid->list, &sequence->list);
 884         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
 885                 goto unlock;
 886         rpc_sleep_on(&sequence->wait, task, NULL);
 887         status = -EAGAIN;
 888 unlock:
 889         spin_unlock(&sequence->lock);
 890         return status;
 891 }
 892
 893 static int nfs4_run_state_manager(void *);
 894
 895 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
 896 {
 897         smp_mb__before_clear_bit();
 898         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
 899         smp_mb__after_clear_bit();
 900         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
 901         rpc_wake_up(&clp->cl_rpcwaitq);
 902 }
 903
 904 /*
 905  * Schedule the nfs_client asynchronous state management routine
 906  */
 907 void nfs4_schedule_state_manager(struct nfs_client *clp)
 908 {
 909         struct task_struct *task;
 910
 911         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
 912                 return;
 913         __module_get(THIS_MODULE);
 914         atomic_inc(&clp->cl_count);
 915         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
 916                                 rpc_peeraddr2str(clp->cl_rpcclient,
 917                                                         RPC_DISPLAY_ADDR));
 918         if (!IS_ERR(task))
 919                 return;
 920         nfs4_clear_state_manager_bit(clp);
 921         nfs_put_client(clp);
 922         module_put(THIS_MODULE);
 923 }
 924
 925 /*
 926  * Schedule a state recovery attempt
 927  */
 928 void nfs4_schedule_state_recovery(struct nfs_client *clp)
 929 {
 930         if (!clp)
 931                 return;
 932         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
 933                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
 934         nfs4_schedule_state_manager(clp);
 935 }
 936
 937 int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
 938 {
 939
 940         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 941         /* Don't recover state that expired before the reboot */
 942         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
 943                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 944                 return 0;
 945         }
 946         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
 947         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
 948         return 1;
 949 }
 950
 951 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
 952 {
 953         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
 954         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 955         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
 956         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
 957         return 1;
 958 }
 959
 960 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
 961 {
 962         struct inode *inode = state->inode;
 963         struct nfs_inode *nfsi = NFS_I(inode);
 964         struct file_lock *fl;
 965         int status = 0;
 966
 967         if (inode->i_flock == NULL)
 968                 return 0;
 969
 970         /* Guard against delegation returns and new lock/unlock calls */
 971         down_write(&nfsi->rwsem);
 972         /* Protect inode->i_flock using the BKL */
 973         lock_flocks();
 974         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
 975                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
 976                         continue;
 977                 if (nfs_file_open_context(fl->fl_file)->state != state)
 978                         continue;
 979                 unlock_flocks();
 980                 status = ops->recover_lock(state, fl);
 981                 switch (status) {
 982                         case 0:
 983                                 break;
 984                         case -ESTALE:
 985                         case -NFS4ERR_ADMIN_REVOKED:
 986                         case -NFS4ERR_STALE_STATEID:
 987                         case -NFS4ERR_BAD_STATEID:
 988                         case -NFS4ERR_EXPIRED:
 989                         case -NFS4ERR_NO_GRACE:
 990                         case -NFS4ERR_STALE_CLIENTID:
 991                         case -NFS4ERR_BADSESSION:
 992                         case -NFS4ERR_BADSLOT:
 993                         case -NFS4ERR_BAD_HIGH_SLOT:
 994                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 995                                 goto out;
 996                         default:
 997                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 998                                                 __func__, status);
 999                         case -ENOMEM:
1000                         case -NFS4ERR_DENIED:
1001                         case -NFS4ERR_RECLAIM_BAD:
1002                         case -NFS4ERR_RECLAIM_CONFLICT:
1003                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1004                                 status = 0;
1005                 }
1006                 lock_flocks();
1007         }
1008         unlock_flocks();
1009 out:
1010         up_write(&nfsi->rwsem);
1011         return status;
1012 }
1013
1014 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1015 {
1016         struct nfs4_state *state;
1017         struct nfs4_lock_state *lock;
1018         int status = 0;
1019
1020         /* Note: we rely on the sp->so_states list being ordered
1021          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1022          * states first.
1023          * This is needed to ensure that the server won't give us any
1024          * read delegations that we have to return if, say, we are
1025          * recovering after a network partition or a reboot from a
1026          * server that doesn't support a grace period.
1027          */
1028 restart:
1029         spin_lock(&sp->so_lock);
1030         list_for_each_entry(state, &sp->so_states, open_states) {
1031                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1032                         continue;
1033                 if (state->state == 0)
1034                         continue;
1035                 atomic_inc(&state->count);
1036                 spin_unlock(&sp->so_lock);
1037                 status = ops->recover_open(sp, state);
1038                 if (status >= 0) {
1039                         status = nfs4_reclaim_locks(state, ops);
1040                         if (status >= 0) {
1041                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1042                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1043                                                 printk("%s: Lock reclaim failed!\n",
1044                                                         __func__);
1045                                 }
1046                                 nfs4_put_open_state(state);
1047                                 goto restart;
1048                         }
1049                 }
1050                 switch (status) {
1051                         default:
1052                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1053                                                 __func__, status);
1054                         case -ENOENT:
1055                         case -ENOMEM:
1056                         case -ESTALE:
1057                                 /*
1058                                  * Open state on this file cannot be recovered
1059                                  * All we can do is revert to using the zero stateid.
1060                                  */
1061                                 memset(state->stateid.data, 0,
1062                                         sizeof(state->stateid.data));
1063                                 /* Mark the file as being 'closed' */
1064                                 state->state = 0;
1065                                 break;
1066                         case -NFS4ERR_ADMIN_REVOKED:
1067                         case -NFS4ERR_STALE_STATEID:
1068                         case -NFS4ERR_BAD_STATEID:
1069                         case -NFS4ERR_RECLAIM_BAD:
1070                         case -NFS4ERR_RECLAIM_CONFLICT:
1071                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1072                                 break;
1073                         case -NFS4ERR_EXPIRED:
1074                         case -NFS4ERR_NO_GRACE:
1075                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1076                         case -NFS4ERR_STALE_CLIENTID:
1077                         case -NFS4ERR_BADSESSION:
1078                         case -NFS4ERR_BADSLOT:
1079                         case -NFS4ERR_BAD_HIGH_SLOT:
1080                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1081                                 goto out_err;
1082                 }
1083                 nfs4_put_open_state(state);
1084                 goto restart;
1085         }
1086         spin_unlock(&sp->so_lock);
1087         return 0;
1088 out_err:
1089         nfs4_put_open_state(state);
1090         return status;
1091 }
1092
1093 static void nfs4_clear_open_state(struct nfs4_state *state)
1094 {
1095         struct nfs4_lock_state *lock;
1096
1097         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1098         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1099         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1100         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1101         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1102                 lock->ls_seqid.flags = 0;
1103                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1104         }
1105 }
1106
1107 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1108 {
1109         struct nfs4_state_owner *sp;
1110         struct rb_node *pos;
1111         struct nfs4_state *state;
1112
1113         /* Reset all sequence ids to zero */
1114         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1115                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1116                 sp->so_seqid.flags = 0;
1117                 spin_lock(&sp->so_lock);
1118                 list_for_each_entry(state, &sp->so_states, open_states) {
1119                         if (mark_reclaim(clp, state))
1120                                 nfs4_clear_open_state(state);
1121                 }
1122                 spin_unlock(&sp->so_lock);
1123         }
1124 }
1125
1126 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1127 {
1128         /* Mark all delegations for reclaim */
1129         nfs_delegation_mark_reclaim(clp);
1130         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1131 }
1132
1133 static void nfs4_reclaim_complete(struct nfs_client *clp,
1134                                  const struct nfs4_state_recovery_ops *ops)
1135 {
1136         /* Notify the server we're done reclaiming our state */
1137         if (ops->reclaim_complete)
1138                 (void)ops->reclaim_complete(clp);
1139 }
1140
1141 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1142 {
1143         struct nfs4_state_owner *sp;
1144         struct rb_node *pos;
1145         struct nfs4_state *state;
1146
1147         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1148                 return;
1149
1150         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1151
1152         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1153                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1154                 spin_lock(&sp->so_lock);
1155                 list_for_each_entry(state, &sp->so_states, open_states) {
1156                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
1157                                 continue;
1158                         nfs4_state_mark_reclaim_nograce(clp, state);
1159                 }
1160                 spin_unlock(&sp->so_lock);
1161         }
1162
1163         nfs_delegation_reap_unclaimed(clp);
1164 }
1165
1166 static void nfs_delegation_clear_all(struct nfs_client *clp)
1167 {
1168         nfs_delegation_mark_reclaim(clp);
1169         nfs_delegation_reap_unclaimed(clp);
1170 }
1171
1172 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1173 {
1174         nfs_delegation_clear_all(clp);
1175         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1176 }
1177
1178 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1179 {
1180         switch (error) {
1181                 case -NFS4ERR_CB_PATH_DOWN:
1182                         nfs_handle_cb_pathdown(clp);
1183                         return 0;
1184                 case -NFS4ERR_NO_GRACE:
1185                         nfs4_state_end_reclaim_reboot(clp);
1186                         return 0;
1187                 case -NFS4ERR_STALE_CLIENTID:
1188                 case -NFS4ERR_LEASE_MOVED:
1189                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1190                         nfs4_state_end_reclaim_reboot(clp);
1191                         nfs4_state_start_reclaim_reboot(clp);
1192                         break;
1193                 case -NFS4ERR_EXPIRED:
1194                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1195                         nfs4_state_start_reclaim_nograce(clp);
1196                         break;
1197                 case -NFS4ERR_BADSESSION:
1198                 case -NFS4ERR_BADSLOT:
1199                 case -NFS4ERR_BAD_HIGH_SLOT:
1200                 case -NFS4ERR_DEADSESSION:
1201                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1202                 case -NFS4ERR_SEQ_FALSE_RETRY:
1203                 case -NFS4ERR_SEQ_MISORDERED:
1204                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1205                         /* Zero session reset errors */
1206                         return 0;
1207         }
1208         return error;
1209 }
1210
1211 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1212 {
1213         struct rb_node *pos;
1214         int status = 0;
1215
1216 restart:
1217         spin_lock(&clp->cl_lock);
1218         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1219                 struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1220                 if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
1221                         continue;
1222                 atomic_inc(&sp->so_count);
1223                 spin_unlock(&clp->cl_lock);
1224                 status = nfs4_reclaim_open_state(sp, ops);
1225                 if (status < 0) {
1226                         set_bit(ops->owner_flag_bit, &sp->so_flags);
1227                         nfs4_put_state_owner(sp);
1228                         return nfs4_recovery_handle_error(clp, status);
1229                 }
1230                 nfs4_put_state_owner(sp);
1231                 goto restart;
1232         }
1233         spin_unlock(&clp->cl_lock);
1234         return status;
1235 }
1236
1237 static int nfs4_check_lease(struct nfs_client *clp)
1238 {
1239         struct rpc_cred *cred;
1240         const struct nfs4_state_maintenance_ops *ops =
1241                 clp->cl_mvops->state_renewal_ops;
1242         int status = -NFS4ERR_EXPIRED;
1243
1244         /* Is the client already known to have an expired lease? */
1245         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1246                 return 0;
1247         spin_lock(&clp->cl_lock);
1248         cred = ops->get_state_renewal_cred_locked(clp);
1249         spin_unlock(&clp->cl_lock);
1250         if (cred == NULL) {
1251                 cred = nfs4_get_setclientid_cred(clp);
1252                 if (cred == NULL)
1253                         goto out;
1254         }
1255         status = ops->renew_lease(clp, cred);
1256         put_rpccred(cred);
1257 out:
1258         return nfs4_recovery_handle_error(clp, status);
1259 }
1260
1261 static int nfs4_reclaim_lease(struct nfs_client *clp)
1262 {
1263         struct rpc_cred *cred;
1264         const struct nfs4_state_recovery_ops *ops =
1265                 clp->cl_mvops->reboot_recovery_ops;
1266         int status = -ENOENT;
1267
1268         cred = ops->get_clid_cred(clp);
1269         if (cred != NULL) {
1270                 status = ops->establish_clid(clp, cred);
1271                 put_rpccred(cred);
1272                 /* Handle case where the user hasn't set up machine creds */
1273                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1274                         nfs4_clear_machine_cred(clp);
1275                         status = -EAGAIN;
1276                 }
1277                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1278                         status = -EPROTONOSUPPORT;
1279         }
1280         return status;
1281 }
1282
1283 #ifdef CONFIG_NFS_V4_1
1284 void nfs41_handle_recall_slot(struct nfs_client *clp)
1285 {
1286         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1287         nfs4_schedule_state_recovery(clp);
1288 }
1289
1290 static void nfs4_reset_all_state(struct nfs_client *clp)
1291 {
1292         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1293                 clp->cl_boot_time = CURRENT_TIME;
1294                 nfs4_state_start_reclaim_nograce(clp);
1295                 nfs4_schedule_state_recovery(clp);
1296         }
1297 }
1298
1299 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1300 {
1301         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1302                 nfs4_state_start_reclaim_reboot(clp);
1303                 nfs4_schedule_state_recovery(clp);
1304         }
1305 }
1306
1307 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1308 {
1309         /* Temporary */
1310         nfs4_reset_all_state(clp);
1311 }
1312
1313 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1314 {
1315         /* This will need to handle layouts too */
1316         nfs_expire_all_delegations(clp);
1317 }
1318
1319 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1320 {
1321         nfs_expire_all_delegations(clp);
1322         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1323                 nfs4_schedule_state_recovery(clp);
1324 }
1325
1326 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1327 {
1328         if (!flags)
1329                 return;
1330         else if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1331                 nfs41_handle_server_reboot(clp);
1332         else if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1333                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1334                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1335                             SEQ4_STATUS_LEASE_MOVED))
1336                 nfs41_handle_state_revoked(clp);
1337         else if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1338                 nfs41_handle_recallable_state_revoked(clp);
1339         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1340                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1341                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1342                 nfs41_handle_cb_path_down(clp);
1343 }
1344
1345 static int nfs4_reset_session(struct nfs_client *clp)
1346 {
1347         int status;
1348
1349         nfs4_begin_drain_session(clp);
1350         status = nfs4_proc_destroy_session(clp->cl_session);
1351         if (status && status != -NFS4ERR_BADSESSION &&
1352             status != -NFS4ERR_DEADSESSION) {
1353                 status = nfs4_recovery_handle_error(clp, status);
1354                 goto out;
1355         }
1356
1357         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1358         status = nfs4_proc_create_session(clp);
1359         if (status) {
1360                 status = nfs4_recovery_handle_error(clp, status);
1361                 goto out;
1362         }
1363         /* create_session negotiated new slot table */
1364         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1365
1366          /* Let the state manager reestablish state */
1367         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1368                 nfs41_setup_state_renewal(clp);
1369 out:
1370         return status;
1371 }
1372
1373 static int nfs4_recall_slot(struct nfs_client *clp)
1374 {
1375         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1376         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1377         struct nfs4_slot *new, *old;
1378         int i;
1379
1380         nfs4_begin_drain_session(clp);
1381         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1382                       GFP_NOFS);
1383         if (!new)
1384                 return -ENOMEM;
1385
1386         spin_lock(&fc_tbl->slot_tbl_lock);
1387         for (i = 0; i < fc_tbl->target_max_slots; i++)
1388                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1389         old = fc_tbl->slots;
1390         fc_tbl->slots = new;
1391         fc_tbl->max_slots = fc_tbl->target_max_slots;
1392         fc_tbl->target_max_slots = 0;
1393         fc_attrs->max_reqs = fc_tbl->max_slots;
1394         spin_unlock(&fc_tbl->slot_tbl_lock);
1395
1396         kfree(old);
1397         nfs4_end_drain_session(clp);
1398         return 0;
1399 }
1400
1401 #else /* CONFIG_NFS_V4_1 */
1402 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1403 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1404 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1405 #endif /* CONFIG_NFS_V4_1 */
1406
1407 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1408  * on EXCHANGE_ID for v4.1
1409  */
1410 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1411 {
1412         if (nfs4_has_session(clp)) {
1413                 switch (status) {
1414                 case -NFS4ERR_DELAY:
1415                 case -NFS4ERR_CLID_INUSE:
1416                 case -EAGAIN:
1417                 case -EKEYEXPIRED:
1418                         break;
1419
1420                 case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1421                                          * in nfs4_exchange_id */
1422                 default:
1423                         return;
1424                 }
1425         }
1426         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1427 }
1428
1429 static void nfs4_state_manager(struct nfs_client *clp)
1430 {
1431         int status = 0;
1432
1433         /* Ensure exclusive access to NFSv4 state */
1434         for(;;) {
1435                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1436                         /* We're going to have to re-establish a clientid */
1437                         status = nfs4_reclaim_lease(clp);
1438                         if (status) {
1439                                 nfs4_set_lease_expired(clp, status);
1440                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1441                                                         &clp->cl_state))
1442                                         continue;
1443                                 if (clp->cl_cons_state ==
1444                                                         NFS_CS_SESSION_INITING)
1445                                         nfs_mark_client_ready(clp, status);
1446                                 goto out_error;
1447                         }
1448                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1449                         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1450                 }
1451
1452                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1453                         status = nfs4_check_lease(clp);
1454                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1455                                 continue;
1456                         if (status < 0 && status != -NFS4ERR_CB_PATH_DOWN)
1457                                 goto out_error;
1458                 }
1459
1460                 /* Initialize or reset the session */
1461                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1462                    && nfs4_has_session(clp)) {
1463                         status = nfs4_reset_session(clp);
1464                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1465                                 continue;
1466                         if (status < 0)
1467                                 goto out_error;
1468                 }
1469
1470                 /* First recover reboot state... */
1471                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1472                         status = nfs4_do_reclaim(clp,
1473                                 clp->cl_mvops->reboot_recovery_ops);
1474                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1475                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1476                                 continue;
1477                         nfs4_state_end_reclaim_reboot(clp);
1478                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1479                                 continue;
1480                         if (status < 0)
1481                                 goto out_error;
1482                 }
1483
1484                 /* Now recover expired state... */
1485                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1486                         status = nfs4_do_reclaim(clp,
1487                                 clp->cl_mvops->nograce_recovery_ops);
1488                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1489                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1490                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1491                                 continue;
1492                         if (status < 0)
1493                                 goto out_error;
1494                 }
1495
1496                 nfs4_end_drain_session(clp);
1497                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1498                         nfs_client_return_marked_delegations(clp);
1499                         continue;
1500                 }
1501                 /* Recall session slots */
1502                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1503                    && nfs4_has_session(clp)) {
1504                         status = nfs4_recall_slot(clp);
1505                         if (status < 0)
1506                                 goto out_error;
1507                         continue;
1508                 }
1509
1510
1511                 nfs4_clear_state_manager_bit(clp);
1512                 /* Did we race with an attempt to give us more work? */
1513                 if (clp->cl_state == 0)
1514                         break;
1515                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1516                         break;
1517         }
1518         return;
1519 out_error:
1520         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1521                         " with error %d\n", clp->cl_hostname, -status);
1522         nfs4_end_drain_session(clp);
1523         nfs4_clear_state_manager_bit(clp);
1524 }
1525
1526 static int nfs4_run_state_manager(void *ptr)
1527 {
1528         struct nfs_client *clp = ptr;
1529
1530         allow_signal(SIGKILL);
1531         nfs4_state_manager(clp);
1532         nfs_put_client(clp);
1533         module_put_and_exit(0);
1534         return 0;
1535 }
1536
1537 /*
1538  * Local variables:
1539  *  c-basic-offset: 8
1540  * End:
1541  */