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   1 /*
   2  *  fs/nfs/nfs4state.c
   3  *
   4  *  Client-side XDR for NFSv4.
   5  *
   6  *  Copyright (c) 2002 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Kendrick Smith <kmsmith@umich.edu>
  10  *
  11  *  Redistribution and use in source and binary forms, with or without
  12  *  modification, are permitted provided that the following conditions
  13  *  are met:
  14  *
  15  *  1. Redistributions of source code must retain the above copyright
  16  *     notice, this list of conditions and the following disclaimer.
  17  *  2. Redistributions in binary form must reproduce the above copyright
  18  *     notice, this list of conditions and the following disclaimer in the
  19  *     documentation and/or other materials provided with the distribution.
  20  *  3. Neither the name of the University nor the names of its
  21  *     contributors may be used to endorse or promote products derived
  22  *     from this software without specific prior written permission.
  23  *
  24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  * Implementation of the NFSv4 state model.  For the time being,
  37  * this is minimal, but will be made much more complex in a
  38  * subsequent patch.
  39  */
  40
  41 #include <linux/kernel.h>
  42 #include <linux/slab.h>
  43 #include <linux/smp_lock.h>
  44 #include <linux/nfs_fs.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/kthread.h>
  47 #include <linux/module.h>
  48 #include <linux/random.h>
  49 #include <linux/workqueue.h>
  50 #include <linux/bitops.h>
  51
  52 #include "nfs4_fs.h"
  53 #include "callback.h"
  54 #include "delegation.h"
  55 #include "internal.h"
  56
  57 #define OPENOWNER_POOL_SIZE     8
  58
  59 const nfs4_stateid zero_stateid;
  60
  61 static LIST_HEAD(nfs4_clientid_list);
  62
  63 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  64 {
  65         unsigned short port;
  66         int status;
  67
  68         port = nfs_callback_tcpport;
  69         if (clp->cl_addr.ss_family == AF_INET6)
  70                 port = nfs_callback_tcpport6;
  71
  72         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred);
  73         if (status == 0)
  74                 status = nfs4_proc_setclientid_confirm(clp, cred);
  75         if (status == 0)
  76                 nfs4_schedule_state_renewal(clp);
  77         return status;
  78 }
  79
  80 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
  81 {
  82         struct rpc_cred *cred = NULL;
  83
  84         if (clp->cl_machine_cred != NULL)
  85                 cred = get_rpccred(clp->cl_machine_cred);
  86         return cred;
  87 }
  88
  89 static void nfs4_clear_machine_cred(struct nfs_client *clp)
  90 {
  91         struct rpc_cred *cred;
  92
  93         spin_lock(&clp->cl_lock);
  94         cred = clp->cl_machine_cred;
  95         clp->cl_machine_cred = NULL;
  96         spin_unlock(&clp->cl_lock);
  97         if (cred != NULL)
  98                 put_rpccred(cred);
  99 }
 100
 101 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 102 {
 103         struct nfs4_state_owner *sp;
 104         struct rb_node *pos;
 105         struct rpc_cred *cred = NULL;
 106
 107         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
 108                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 109                 if (list_empty(&sp->so_states))
 110                         continue;
 111                 cred = get_rpccred(sp->so_cred);
 112                 break;
 113         }
 114         return cred;
 115 }
 116
 117 #if defined(CONFIG_NFS_V4_1)
 118
 119 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 120 {
 121         int status;
 122         struct nfs_fsinfo fsinfo;
 123
 124         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 125         if (status == 0) {
 126                 /* Update lease time and schedule renewal */
 127                 spin_lock(&clp->cl_lock);
 128                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 129                 clp->cl_last_renewal = jiffies;
 130                 spin_unlock(&clp->cl_lock);
 131
 132                 nfs4_schedule_state_renewal(clp);
 133         }
 134
 135         return status;
 136 }
 137
 138 static void nfs41_end_drain_session(struct nfs_client *clp,
 139                 struct nfs4_session *ses)
 140 {
 141         if (test_and_clear_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state))
 142                 rpc_wake_up(&ses->fc_slot_table.slot_tbl_waitq);
 143 }
 144
 145 static int nfs41_begin_drain_session(struct nfs_client *clp,
 146                 struct nfs4_session *ses)
 147 {
 148         struct nfs4_slot_table *tbl = &ses->fc_slot_table;
 149
 150         spin_lock(&tbl->slot_tbl_lock);
 151         set_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state);
 152         if (tbl->highest_used_slotid != -1) {
 153                 INIT_COMPLETION(ses->complete);
 154                 spin_unlock(&tbl->slot_tbl_lock);
 155                 return wait_for_completion_interruptible(&ses->complete);
 156         }
 157         spin_unlock(&tbl->slot_tbl_lock);
 158         return 0;
 159 }
 160
 161 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 162 {
 163         int status;
 164
 165         status = nfs41_begin_drain_session(clp, clp->cl_session);
 166         if (status != 0)
 167                 goto out;
 168         status = nfs4_proc_exchange_id(clp, cred);
 169         if (status != 0)
 170                 goto out;
 171         status = nfs4_proc_create_session(clp);
 172         if (status != 0)
 173                 goto out;
 174         nfs41_end_drain_session(clp, clp->cl_session);
 175         nfs41_setup_state_renewal(clp);
 176         nfs_mark_client_ready(clp, NFS_CS_READY);
 177 out:
 178         return status;
 179 }
 180
 181 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 182 {
 183         struct rpc_cred *cred;
 184
 185         spin_lock(&clp->cl_lock);
 186         cred = nfs4_get_machine_cred_locked(clp);
 187         spin_unlock(&clp->cl_lock);
 188         return cred;
 189 }
 190
 191 #endif /* CONFIG_NFS_V4_1 */
 192
 193 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 194 {
 195         struct nfs4_state_owner *sp;
 196         struct rb_node *pos;
 197         struct rpc_cred *cred;
 198
 199         spin_lock(&clp->cl_lock);
 200         cred = nfs4_get_machine_cred_locked(clp);
 201         if (cred != NULL)
 202                 goto out;
 203         pos = rb_first(&clp->cl_state_owners);
 204         if (pos != NULL) {
 205                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 206                 cred = get_rpccred(sp->so_cred);
 207         }
 208 out:
 209         spin_unlock(&clp->cl_lock);
 210         return cred;
 211 }
 212
 213 static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
 214                 __u64 minval, int maxbits)
 215 {
 216         struct rb_node **p, *parent;
 217         struct nfs_unique_id *pos;
 218         __u64 mask = ~0ULL;
 219
 220         if (maxbits < 64)
 221                 mask = (1ULL << maxbits) - 1ULL;
 222
 223         /* Ensure distribution is more or less flat */
 224         get_random_bytes(&new->id, sizeof(new->id));
 225         new->id &= mask;
 226         if (new->id < minval)
 227                 new->id += minval;
 228 retry:
 229         p = &root->rb_node;
 230         parent = NULL;
 231
 232         while (*p != NULL) {
 233                 parent = *p;
 234                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 235
 236                 if (new->id < pos->id)
 237                         p = &(*p)->rb_left;
 238                 else if (new->id > pos->id)
 239                         p = &(*p)->rb_right;
 240                 else
 241                         goto id_exists;
 242         }
 243         rb_link_node(&new->rb_node, parent, p);
 244         rb_insert_color(&new->rb_node, root);
 245         return;
 246 id_exists:
 247         for (;;) {
 248                 new->id++;
 249                 if (new->id < minval || (new->id & mask) != new->id) {
 250                         new->id = minval;
 251                         break;
 252                 }
 253                 parent = rb_next(parent);
 254                 if (parent == NULL)
 255                         break;
 256                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 257                 if (new->id < pos->id)
 258                         break;
 259         }
 260         goto retry;
 261 }
 262
 263 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
 264 {
 265         rb_erase(&id->rb_node, root);
 266 }
 267
 268 static struct nfs4_state_owner *
 269 nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 270 {
 271         struct nfs_client *clp = server->nfs_client;
 272         struct rb_node **p = &clp->cl_state_owners.rb_node,
 273                        *parent = NULL;
 274         struct nfs4_state_owner *sp, *res = NULL;
 275
 276         while (*p != NULL) {
 277                 parent = *p;
 278                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 279
 280                 if (server < sp->so_server) {
 281                         p = &parent->rb_left;
 282                         continue;
 283                 }
 284                 if (server > sp->so_server) {
 285                         p = &parent->rb_right;
 286                         continue;
 287                 }
 288                 if (cred < sp->so_cred)
 289                         p = &parent->rb_left;
 290                 else if (cred > sp->so_cred)
 291                         p = &parent->rb_right;
 292                 else {
 293                         atomic_inc(&sp->so_count);
 294                         res = sp;
 295                         break;
 296                 }
 297         }
 298         return res;
 299 }
 300
 301 static struct nfs4_state_owner *
 302 nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
 303 {
 304         struct rb_node **p = &clp->cl_state_owners.rb_node,
 305                        *parent = NULL;
 306         struct nfs4_state_owner *sp;
 307
 308         while (*p != NULL) {
 309                 parent = *p;
 310                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 311
 312                 if (new->so_server < sp->so_server) {
 313                         p = &parent->rb_left;
 314                         continue;
 315                 }
 316                 if (new->so_server > sp->so_server) {
 317                         p = &parent->rb_right;
 318                         continue;
 319                 }
 320                 if (new->so_cred < sp->so_cred)
 321                         p = &parent->rb_left;
 322                 else if (new->so_cred > sp->so_cred)
 323                         p = &parent->rb_right;
 324                 else {
 325                         atomic_inc(&sp->so_count);
 326                         return sp;
 327                 }
 328         }
 329         nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
 330         rb_link_node(&new->so_client_node, parent, p);
 331         rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
 332         return new;
 333 }
 334
 335 static void
 336 nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
 337 {
 338         if (!RB_EMPTY_NODE(&sp->so_client_node))
 339                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 340         nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
 341 }
 342
 343 /*
 344  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 345  * create a new state_owner.
 346  *
 347  */
 348 static struct nfs4_state_owner *
 349 nfs4_alloc_state_owner(void)
 350 {
 351         struct nfs4_state_owner *sp;
 352
 353         sp = kzalloc(sizeof(*sp),GFP_KERNEL);
 354         if (!sp)
 355                 return NULL;
 356         spin_lock_init(&sp->so_lock);
 357         INIT_LIST_HEAD(&sp->so_states);
 358         INIT_LIST_HEAD(&sp->so_delegations);
 359         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 360         sp->so_seqid.sequence = &sp->so_sequence;
 361         spin_lock_init(&sp->so_sequence.lock);
 362         INIT_LIST_HEAD(&sp->so_sequence.list);
 363         atomic_set(&sp->so_count, 1);
 364         return sp;
 365 }
 366
 367 static void
 368 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 369 {
 370         if (!RB_EMPTY_NODE(&sp->so_client_node)) {
 371                 struct nfs_client *clp = sp->so_client;
 372
 373                 spin_lock(&clp->cl_lock);
 374                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 375                 RB_CLEAR_NODE(&sp->so_client_node);
 376                 spin_unlock(&clp->cl_lock);
 377         }
 378 }
 379
 380 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 381 {
 382         struct nfs_client *clp = server->nfs_client;
 383         struct nfs4_state_owner *sp, *new;
 384
 385         spin_lock(&clp->cl_lock);
 386         sp = nfs4_find_state_owner(server, cred);
 387         spin_unlock(&clp->cl_lock);
 388         if (sp != NULL)
 389                 return sp;
 390         new = nfs4_alloc_state_owner();
 391         if (new == NULL)
 392                 return NULL;
 393         new->so_client = clp;
 394         new->so_server = server;
 395         new->so_cred = cred;
 396         spin_lock(&clp->cl_lock);
 397         sp = nfs4_insert_state_owner(clp, new);
 398         spin_unlock(&clp->cl_lock);
 399         if (sp == new)
 400                 get_rpccred(cred);
 401         else {
 402                 rpc_destroy_wait_queue(&new->so_sequence.wait);
 403                 kfree(new);
 404         }
 405         return sp;
 406 }
 407
 408 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 409 {
 410         struct nfs_client *clp = sp->so_client;
 411         struct rpc_cred *cred = sp->so_cred;
 412
 413         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 414                 return;
 415         nfs4_remove_state_owner(clp, sp);
 416         spin_unlock(&clp->cl_lock);
 417         rpc_destroy_wait_queue(&sp->so_sequence.wait);
 418         put_rpccred(cred);
 419         kfree(sp);
 420 }
 421
 422 static struct nfs4_state *
 423 nfs4_alloc_open_state(void)
 424 {
 425         struct nfs4_state *state;
 426
 427         state = kzalloc(sizeof(*state), GFP_KERNEL);
 428         if (!state)
 429                 return NULL;
 430         atomic_set(&state->count, 1);
 431         INIT_LIST_HEAD(&state->lock_states);
 432         spin_lock_init(&state->state_lock);
 433         seqlock_init(&state->seqlock);
 434         return state;
 435 }
 436
 437 void
 438 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 439 {
 440         if (state->state == fmode)
 441                 return;
 442         /* NB! List reordering - see the reclaim code for why.  */
 443         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 444                 if (fmode & FMODE_WRITE)
 445                         list_move(&state->open_states, &state->owner->so_states);
 446                 else
 447                         list_move_tail(&state->open_states, &state->owner->so_states);
 448         }
 449         state->state = fmode;
 450 }
 451
 452 static struct nfs4_state *
 453 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 454 {
 455         struct nfs_inode *nfsi = NFS_I(inode);
 456         struct nfs4_state *state;
 457
 458         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 459                 if (state->owner != owner)
 460                         continue;
 461                 if (atomic_inc_not_zero(&state->count))
 462                         return state;
 463         }
 464         return NULL;
 465 }
 466
 467 static void
 468 nfs4_free_open_state(struct nfs4_state *state)
 469 {
 470         kfree(state);
 471 }
 472
 473 struct nfs4_state *
 474 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 475 {
 476         struct nfs4_state *state, *new;
 477         struct nfs_inode *nfsi = NFS_I(inode);
 478
 479         spin_lock(&inode->i_lock);
 480         state = __nfs4_find_state_byowner(inode, owner);
 481         spin_unlock(&inode->i_lock);
 482         if (state)
 483                 goto out;
 484         new = nfs4_alloc_open_state();
 485         spin_lock(&owner->so_lock);
 486         spin_lock(&inode->i_lock);
 487         state = __nfs4_find_state_byowner(inode, owner);
 488         if (state == NULL && new != NULL) {
 489                 state = new;
 490                 state->owner = owner;
 491                 atomic_inc(&owner->so_count);
 492                 list_add(&state->inode_states, &nfsi->open_states);
 493                 state->inode = igrab(inode);
 494                 spin_unlock(&inode->i_lock);
 495                 /* Note: The reclaim code dictates that we add stateless
 496                  * and read-only stateids to the end of the list */
 497                 list_add_tail(&state->open_states, &owner->so_states);
 498                 spin_unlock(&owner->so_lock);
 499         } else {
 500                 spin_unlock(&inode->i_lock);
 501                 spin_unlock(&owner->so_lock);
 502                 if (new)
 503                         nfs4_free_open_state(new);
 504         }
 505 out:
 506         return state;
 507 }
 508
 509 void nfs4_put_open_state(struct nfs4_state *state)
 510 {
 511         struct inode *inode = state->inode;
 512         struct nfs4_state_owner *owner = state->owner;
 513
 514         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 515                 return;
 516         spin_lock(&inode->i_lock);
 517         list_del(&state->inode_states);
 518         list_del(&state->open_states);
 519         spin_unlock(&inode->i_lock);
 520         spin_unlock(&owner->so_lock);
 521         iput(inode);
 522         nfs4_free_open_state(state);
 523         nfs4_put_state_owner(owner);
 524 }
 525
 526 /*
 527  * Close the current file.
 528  */
 529 static void __nfs4_close(struct path *path, struct nfs4_state *state, fmode_t fmode, int wait)
 530 {
 531         struct nfs4_state_owner *owner = state->owner;
 532         int call_close = 0;
 533         fmode_t newstate;
 534
 535         atomic_inc(&owner->so_count);
 536         /* Protect against nfs4_find_state() */
 537         spin_lock(&owner->so_lock);
 538         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 539                 case FMODE_READ:
 540                         state->n_rdonly--;
 541                         break;
 542                 case FMODE_WRITE:
 543                         state->n_wronly--;
 544                         break;
 545                 case FMODE_READ|FMODE_WRITE:
 546                         state->n_rdwr--;
 547         }
 548         newstate = FMODE_READ|FMODE_WRITE;
 549         if (state->n_rdwr == 0) {
 550                 if (state->n_rdonly == 0) {
 551                         newstate &= ~FMODE_READ;
 552                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 553                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 554                 }
 555                 if (state->n_wronly == 0) {
 556                         newstate &= ~FMODE_WRITE;
 557                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 558                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 559                 }
 560                 if (newstate == 0)
 561                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 562         }
 563         nfs4_state_set_mode_locked(state, newstate);
 564         spin_unlock(&owner->so_lock);
 565
 566         if (!call_close) {
 567                 nfs4_put_open_state(state);
 568                 nfs4_put_state_owner(owner);
 569         } else
 570                 nfs4_do_close(path, state, wait);
 571 }
 572
 573 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
 574 {
 575         __nfs4_close(path, state, fmode, 0);
 576 }
 577
 578 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
 579 {
 580         __nfs4_close(path, state, fmode, 1);
 581 }
 582
 583 /*
 584  * Search the state->lock_states for an existing lock_owner
 585  * that is compatible with current->files
 586  */
 587 static struct nfs4_lock_state *
 588 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 589 {
 590         struct nfs4_lock_state *pos;
 591         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 592                 if (pos->ls_owner != fl_owner)
 593                         continue;
 594                 atomic_inc(&pos->ls_count);
 595                 return pos;
 596         }
 597         return NULL;
 598 }
 599
 600 /*
 601  * Return a compatible lock_state. If no initialized lock_state structure
 602  * exists, return an uninitialized one.
 603  *
 604  */
 605 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 606 {
 607         struct nfs4_lock_state *lsp;
 608         struct nfs_client *clp = state->owner->so_client;
 609
 610         lsp = kzalloc(sizeof(*lsp), GFP_KERNEL);
 611         if (lsp == NULL)
 612                 return NULL;
 613         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 614         spin_lock_init(&lsp->ls_sequence.lock);
 615         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 616         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 617         atomic_set(&lsp->ls_count, 1);
 618         lsp->ls_state = state;
 619         lsp->ls_owner = fl_owner;
 620         spin_lock(&clp->cl_lock);
 621         nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
 622         spin_unlock(&clp->cl_lock);
 623         INIT_LIST_HEAD(&lsp->ls_locks);
 624         return lsp;
 625 }
 626
 627 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 628 {
 629         struct nfs_client *clp = lsp->ls_state->owner->so_client;
 630
 631         spin_lock(&clp->cl_lock);
 632         nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
 633         spin_unlock(&clp->cl_lock);
 634         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 635         kfree(lsp);
 636 }
 637
 638 /*
 639  * Return a compatible lock_state. If no initialized lock_state structure
 640  * exists, return an uninitialized one.
 641  *
 642  */
 643 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 644 {
 645         struct nfs4_lock_state *lsp, *new = NULL;
 646
 647         for(;;) {
 648                 spin_lock(&state->state_lock);
 649                 lsp = __nfs4_find_lock_state(state, owner);
 650                 if (lsp != NULL)
 651                         break;
 652                 if (new != NULL) {
 653                         list_add(&new->ls_locks, &state->lock_states);
 654                         set_bit(LK_STATE_IN_USE, &state->flags);
 655                         lsp = new;
 656                         new = NULL;
 657                         break;
 658                 }
 659                 spin_unlock(&state->state_lock);
 660                 new = nfs4_alloc_lock_state(state, owner);
 661                 if (new == NULL)
 662                         return NULL;
 663         }
 664         spin_unlock(&state->state_lock);
 665         if (new != NULL)
 666                 nfs4_free_lock_state(new);
 667         return lsp;
 668 }
 669
 670 /*
 671  * Release reference to lock_state, and free it if we see that
 672  * it is no longer in use
 673  */
 674 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 675 {
 676         struct nfs4_state *state;
 677
 678         if (lsp == NULL)
 679                 return;
 680         state = lsp->ls_state;
 681         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 682                 return;
 683         list_del(&lsp->ls_locks);
 684         if (list_empty(&state->lock_states))
 685                 clear_bit(LK_STATE_IN_USE, &state->flags);
 686         spin_unlock(&state->state_lock);
 687         nfs4_free_lock_state(lsp);
 688 }
 689
 690 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 691 {
 692         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 693
 694         dst->fl_u.nfs4_fl.owner = lsp;
 695         atomic_inc(&lsp->ls_count);
 696 }
 697
 698 static void nfs4_fl_release_lock(struct file_lock *fl)
 699 {
 700         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 701 }
 702
 703 static const struct file_lock_operations nfs4_fl_lock_ops = {
 704         .fl_copy_lock = nfs4_fl_copy_lock,
 705         .fl_release_private = nfs4_fl_release_lock,
 706 };
 707
 708 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 709 {
 710         struct nfs4_lock_state *lsp;
 711
 712         if (fl->fl_ops != NULL)
 713                 return 0;
 714         lsp = nfs4_get_lock_state(state, fl->fl_owner);
 715         if (lsp == NULL)
 716                 return -ENOMEM;
 717         fl->fl_u.nfs4_fl.owner = lsp;
 718         fl->fl_ops = &nfs4_fl_lock_ops;
 719         return 0;
 720 }
 721
 722 /*
 723  * Byte-range lock aware utility to initialize the stateid of read/write
 724  * requests.
 725  */
 726 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
 727 {
 728         struct nfs4_lock_state *lsp;
 729         int seq;
 730
 731         do {
 732                 seq = read_seqbegin(&state->seqlock);
 733                 memcpy(dst, &state->stateid, sizeof(*dst));
 734         } while (read_seqretry(&state->seqlock, seq));
 735         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 736                 return;
 737
 738         spin_lock(&state->state_lock);
 739         lsp = __nfs4_find_lock_state(state, fl_owner);
 740         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 741                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 742         spin_unlock(&state->state_lock);
 743         nfs4_put_lock_state(lsp);
 744 }
 745
 746 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
 747 {
 748         struct nfs_seqid *new;
 749
 750         new = kmalloc(sizeof(*new), GFP_KERNEL);
 751         if (new != NULL) {
 752                 new->sequence = counter;
 753                 INIT_LIST_HEAD(&new->list);
 754         }
 755         return new;
 756 }
 757
 758 void nfs_free_seqid(struct nfs_seqid *seqid)
 759 {
 760         if (!list_empty(&seqid->list)) {
 761                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 762
 763                 spin_lock(&sequence->lock);
 764                 list_del(&seqid->list);
 765                 spin_unlock(&sequence->lock);
 766                 rpc_wake_up(&sequence->wait);
 767         }
 768         kfree(seqid);
 769 }
 770
 771 /*
 772  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 773  * failed with a seqid incrementing error -
 774  * see comments nfs_fs.h:seqid_mutating_error()
 775  */
 776 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 777 {
 778         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 779         switch (status) {
 780                 case 0:
 781                         break;
 782                 case -NFS4ERR_BAD_SEQID:
 783                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
 784                                 return;
 785                         printk(KERN_WARNING "NFS: v4 server returned a bad"
 786                                         " sequence-id error on an"
 787                                         " unconfirmed sequence %p!\n",
 788                                         seqid->sequence);
 789                 case -NFS4ERR_STALE_CLIENTID:
 790                 case -NFS4ERR_STALE_STATEID:
 791                 case -NFS4ERR_BAD_STATEID:
 792                 case -NFS4ERR_BADXDR:
 793                 case -NFS4ERR_RESOURCE:
 794                 case -NFS4ERR_NOFILEHANDLE:
 795                         /* Non-seqid mutating errors */
 796                         return;
 797         };
 798         /*
 799          * Note: no locking needed as we are guaranteed to be first
 800          * on the sequence list
 801          */
 802         seqid->sequence->counter++;
 803 }
 804
 805 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
 806 {
 807         struct nfs4_state_owner *sp = container_of(seqid->sequence,
 808                                         struct nfs4_state_owner, so_seqid);
 809         struct nfs_server *server = sp->so_server;
 810
 811         if (status == -NFS4ERR_BAD_SEQID)
 812                 nfs4_drop_state_owner(sp);
 813         if (!nfs4_has_session(server->nfs_client))
 814                 nfs_increment_seqid(status, seqid);
 815 }
 816
 817 /*
 818  * Increment the seqid if the LOCK/LOCKU succeeded, or
 819  * failed with a seqid incrementing error -
 820  * see comments nfs_fs.h:seqid_mutating_error()
 821  */
 822 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
 823 {
 824         nfs_increment_seqid(status, seqid);
 825 }
 826
 827 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
 828 {
 829         struct rpc_sequence *sequence = seqid->sequence->sequence;
 830         int status = 0;
 831
 832         spin_lock(&sequence->lock);
 833         if (list_empty(&seqid->list))
 834                 list_add_tail(&seqid->list, &sequence->list);
 835         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
 836                 goto unlock;
 837         rpc_sleep_on(&sequence->wait, task, NULL);
 838         status = -EAGAIN;
 839 unlock:
 840         spin_unlock(&sequence->lock);
 841         return status;
 842 }
 843
 844 static int nfs4_run_state_manager(void *);
 845
 846 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
 847 {
 848         smp_mb__before_clear_bit();
 849         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
 850         smp_mb__after_clear_bit();
 851         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
 852         rpc_wake_up(&clp->cl_rpcwaitq);
 853 }
 854
 855 /*
 856  * Schedule the nfs_client asynchronous state management routine
 857  */
 858 void nfs4_schedule_state_manager(struct nfs_client *clp)
 859 {
 860         struct task_struct *task;
 861
 862         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
 863                 return;
 864         __module_get(THIS_MODULE);
 865         atomic_inc(&clp->cl_count);
 866         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
 867                                 rpc_peeraddr2str(clp->cl_rpcclient,
 868                                                         RPC_DISPLAY_ADDR));
 869         if (!IS_ERR(task))
 870                 return;
 871         nfs4_clear_state_manager_bit(clp);
 872         nfs_put_client(clp);
 873         module_put(THIS_MODULE);
 874 }
 875
 876 /*
 877  * Schedule a state recovery attempt
 878  */
 879 void nfs4_schedule_state_recovery(struct nfs_client *clp)
 880 {
 881         if (!clp)
 882                 return;
 883         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
 884                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
 885         nfs4_schedule_state_manager(clp);
 886 }
 887
 888 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
 889 {
 890
 891         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 892         /* Don't recover state that expired before the reboot */
 893         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
 894                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 895                 return 0;
 896         }
 897         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
 898         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
 899         return 1;
 900 }
 901
 902 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
 903 {
 904         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
 905         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 906         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
 907         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
 908         return 1;
 909 }
 910
 911 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
 912 {
 913         struct inode *inode = state->inode;
 914         struct nfs_inode *nfsi = NFS_I(inode);
 915         struct file_lock *fl;
 916         int status = 0;
 917
 918         if (inode->i_flock == NULL)
 919                 return 0;
 920
 921         /* Guard against delegation returns and new lock/unlock calls */
 922         down_write(&nfsi->rwsem);
 923         /* Protect inode->i_flock using the BKL */
 924         lock_kernel();
 925         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
 926                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
 927                         continue;
 928                 if (nfs_file_open_context(fl->fl_file)->state != state)
 929                         continue;
 930                 unlock_kernel();
 931                 status = ops->recover_lock(state, fl);
 932                 switch (status) {
 933                         case 0:
 934                                 break;
 935                         case -ESTALE:
 936                         case -NFS4ERR_ADMIN_REVOKED:
 937                         case -NFS4ERR_STALE_STATEID:
 938                         case -NFS4ERR_BAD_STATEID:
 939                         case -NFS4ERR_EXPIRED:
 940                         case -NFS4ERR_NO_GRACE:
 941                         case -NFS4ERR_STALE_CLIENTID:
 942                         case -NFS4ERR_BADSESSION:
 943                         case -NFS4ERR_BADSLOT:
 944                         case -NFS4ERR_BAD_HIGH_SLOT:
 945                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 946                                 goto out;
 947                         default:
 948                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 949                                                 __func__, status);
 950                         case -ENOMEM:
 951                         case -NFS4ERR_DENIED:
 952                         case -NFS4ERR_RECLAIM_BAD:
 953                         case -NFS4ERR_RECLAIM_CONFLICT:
 954                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
 955                                 status = 0;
 956                 }
 957                 lock_kernel();
 958         }
 959         unlock_kernel();
 960 out:
 961         up_write(&nfsi->rwsem);
 962         return status;
 963 }
 964
 965 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
 966 {
 967         struct nfs4_state *state;
 968         struct nfs4_lock_state *lock;
 969         int status = 0;
 970
 971         /* Note: we rely on the sp->so_states list being ordered
 972          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
 973          * states first.
 974          * This is needed to ensure that the server won't give us any
 975          * read delegations that we have to return if, say, we are
 976          * recovering after a network partition or a reboot from a
 977          * server that doesn't support a grace period.
 978          */
 979 restart:
 980         spin_lock(&sp->so_lock);
 981         list_for_each_entry(state, &sp->so_states, open_states) {
 982                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
 983                         continue;
 984                 if (state->state == 0)
 985                         continue;
 986                 atomic_inc(&state->count);
 987                 spin_unlock(&sp->so_lock);
 988                 status = ops->recover_open(sp, state);
 989                 if (status >= 0) {
 990                         status = nfs4_reclaim_locks(state, ops);
 991                         if (status >= 0) {
 992                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
 993                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
 994                                                 printk("%s: Lock reclaim failed!\n",
 995                                                         __func__);
 996                                 }
 997                                 nfs4_put_open_state(state);
 998                                 goto restart;
 999                         }
1000                 }
1001                 switch (status) {
1002                         default:
1003                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1004                                                 __func__, status);
1005                         case -ENOENT:
1006                         case -ENOMEM:
1007                         case -ESTALE:
1008                                 /*
1009                                  * Open state on this file cannot be recovered
1010                                  * All we can do is revert to using the zero stateid.
1011                                  */
1012                                 memset(state->stateid.data, 0,
1013                                         sizeof(state->stateid.data));
1014                                 /* Mark the file as being 'closed' */
1015                                 state->state = 0;
1016                                 break;
1017                         case -NFS4ERR_ADMIN_REVOKED:
1018                         case -NFS4ERR_STALE_STATEID:
1019                         case -NFS4ERR_BAD_STATEID:
1020                         case -NFS4ERR_RECLAIM_BAD:
1021                         case -NFS4ERR_RECLAIM_CONFLICT:
1022                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
1023                                 break;
1024                         case -NFS4ERR_EXPIRED:
1025                         case -NFS4ERR_NO_GRACE:
1026                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
1027                         case -NFS4ERR_STALE_CLIENTID:
1028                         case -NFS4ERR_BADSESSION:
1029                         case -NFS4ERR_BADSLOT:
1030                         case -NFS4ERR_BAD_HIGH_SLOT:
1031                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1032                                 goto out_err;
1033                 }
1034                 nfs4_put_open_state(state);
1035                 goto restart;
1036         }
1037         spin_unlock(&sp->so_lock);
1038         return 0;
1039 out_err:
1040         nfs4_put_open_state(state);
1041         return status;
1042 }
1043
1044 static void nfs4_clear_open_state(struct nfs4_state *state)
1045 {
1046         struct nfs4_lock_state *lock;
1047
1048         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1049         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1050         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1051         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1052         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1053                 lock->ls_seqid.flags = 0;
1054                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1055         }
1056 }
1057
1058 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1059 {
1060         struct nfs4_state_owner *sp;
1061         struct rb_node *pos;
1062         struct nfs4_state *state;
1063
1064         /* Reset all sequence ids to zero */
1065         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1066                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1067                 sp->so_seqid.flags = 0;
1068                 spin_lock(&sp->so_lock);
1069                 list_for_each_entry(state, &sp->so_states, open_states) {
1070                         if (mark_reclaim(clp, state))
1071                                 nfs4_clear_open_state(state);
1072                 }
1073                 spin_unlock(&sp->so_lock);
1074         }
1075 }
1076
1077 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1078 {
1079         /* Mark all delegations for reclaim */
1080         nfs_delegation_mark_reclaim(clp);
1081         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1082 }
1083
1084 static void nfs4_reclaim_complete(struct nfs_client *clp,
1085                                  const struct nfs4_state_recovery_ops *ops)
1086 {
1087         /* Notify the server we're done reclaiming our state */
1088         if (ops->reclaim_complete)
1089                 (void)ops->reclaim_complete(clp);
1090 }
1091
1092 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1093 {
1094         struct nfs4_state_owner *sp;
1095         struct rb_node *pos;
1096         struct nfs4_state *state;
1097
1098         nfs4_reclaim_complete(clp,
1099                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1100
1101         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1102                 return;
1103
1104         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1105                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1106                 spin_lock(&sp->so_lock);
1107                 list_for_each_entry(state, &sp->so_states, open_states) {
1108                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
1109                                 continue;
1110                         nfs4_state_mark_reclaim_nograce(clp, state);
1111                 }
1112                 spin_unlock(&sp->so_lock);
1113         }
1114
1115         nfs_delegation_reap_unclaimed(clp);
1116 }
1117
1118 static void nfs_delegation_clear_all(struct nfs_client *clp)
1119 {
1120         nfs_delegation_mark_reclaim(clp);
1121         nfs_delegation_reap_unclaimed(clp);
1122 }
1123
1124 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1125 {
1126         nfs_delegation_clear_all(clp);
1127         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1128 }
1129
1130 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1131 {
1132         switch (error) {
1133                 case -NFS4ERR_CB_PATH_DOWN:
1134                         nfs_handle_cb_pathdown(clp);
1135                         return 0;
1136                 case -NFS4ERR_NO_GRACE:
1137                         nfs4_state_end_reclaim_reboot(clp);
1138                         return 0;
1139                 case -NFS4ERR_STALE_CLIENTID:
1140                 case -NFS4ERR_LEASE_MOVED:
1141                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1142                         nfs4_state_end_reclaim_reboot(clp);
1143                         nfs4_state_start_reclaim_reboot(clp);
1144                         break;
1145                 case -NFS4ERR_EXPIRED:
1146                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1147                         nfs4_state_start_reclaim_nograce(clp);
1148                         break;
1149                 case -NFS4ERR_BADSESSION:
1150                 case -NFS4ERR_BADSLOT:
1151                 case -NFS4ERR_BAD_HIGH_SLOT:
1152                 case -NFS4ERR_DEADSESSION:
1153                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1154                 case -NFS4ERR_SEQ_FALSE_RETRY:
1155                 case -NFS4ERR_SEQ_MISORDERED:
1156                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1157                         /* Zero session reset errors */
1158                         return 0;
1159         }
1160         return error;
1161 }
1162
1163 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1164 {
1165         struct rb_node *pos;
1166         int status = 0;
1167
1168 restart:
1169         spin_lock(&clp->cl_lock);
1170         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1171                 struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1172                 if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
1173                         continue;
1174                 atomic_inc(&sp->so_count);
1175                 spin_unlock(&clp->cl_lock);
1176                 status = nfs4_reclaim_open_state(sp, ops);
1177                 if (status < 0) {
1178                         set_bit(ops->owner_flag_bit, &sp->so_flags);
1179                         nfs4_put_state_owner(sp);
1180                         return nfs4_recovery_handle_error(clp, status);
1181                 }
1182                 nfs4_put_state_owner(sp);
1183                 goto restart;
1184         }
1185         spin_unlock(&clp->cl_lock);
1186         return status;
1187 }
1188
1189 static int nfs4_check_lease(struct nfs_client *clp)
1190 {
1191         struct rpc_cred *cred;
1192         struct nfs4_state_maintenance_ops *ops =
1193                 nfs4_state_renewal_ops[clp->cl_minorversion];
1194         int status = -NFS4ERR_EXPIRED;
1195
1196         /* Is the client already known to have an expired lease? */
1197         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1198                 return 0;
1199         spin_lock(&clp->cl_lock);
1200         cred = ops->get_state_renewal_cred_locked(clp);
1201         spin_unlock(&clp->cl_lock);
1202         if (cred == NULL) {
1203                 cred = nfs4_get_setclientid_cred(clp);
1204                 if (cred == NULL)
1205                         goto out;
1206         }
1207         status = ops->renew_lease(clp, cred);
1208         put_rpccred(cred);
1209 out:
1210         return nfs4_recovery_handle_error(clp, status);
1211 }
1212
1213 static int nfs4_reclaim_lease(struct nfs_client *clp)
1214 {
1215         struct rpc_cred *cred;
1216         struct nfs4_state_recovery_ops *ops =
1217                 nfs4_reboot_recovery_ops[clp->cl_minorversion];
1218         int status = -ENOENT;
1219
1220         cred = ops->get_clid_cred(clp);
1221         if (cred != NULL) {
1222                 status = ops->establish_clid(clp, cred);
1223                 put_rpccred(cred);
1224                 /* Handle case where the user hasn't set up machine creds */
1225                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1226                         nfs4_clear_machine_cred(clp);
1227                         status = -EAGAIN;
1228                 }
1229                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1230                         status = -EPROTONOSUPPORT;
1231         }
1232         return status;
1233 }
1234
1235 #ifdef CONFIG_NFS_V4_1
1236 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1237 {
1238         if (!flags)
1239                 return;
1240         else if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED) {
1241                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1242                 nfs4_state_start_reclaim_reboot(clp);
1243                 nfs4_schedule_state_recovery(clp);
1244         } else if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1245                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1246                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1247                             SEQ4_STATUS_RECALLABLE_STATE_REVOKED |
1248                             SEQ4_STATUS_LEASE_MOVED)) {
1249                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1250                 nfs4_state_start_reclaim_nograce(clp);
1251                 nfs4_schedule_state_recovery(clp);
1252         } else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1253                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1254                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1255                 nfs_expire_all_delegations(clp);
1256 }
1257
1258 static void nfs4_session_recovery_handle_error(struct nfs_client *clp, int err)
1259 {
1260         switch (err) {
1261         case -NFS4ERR_STALE_CLIENTID:
1262                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1263         }
1264 }
1265
1266 static int nfs4_reset_session(struct nfs_client *clp)
1267 {
1268         struct nfs4_session *ses = clp->cl_session;
1269         int status;
1270
1271         status = nfs41_begin_drain_session(clp, ses);
1272         if (status != 0)
1273                 return status;
1274
1275         status = nfs4_proc_destroy_session(clp->cl_session);
1276         if (status && status != -NFS4ERR_BADSESSION &&
1277             status != -NFS4ERR_DEADSESSION) {
1278                 nfs4_session_recovery_handle_error(clp, status);
1279                 goto out;
1280         }
1281
1282         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1283         status = nfs4_proc_create_session(clp);
1284         if (status)
1285                 nfs4_session_recovery_handle_error(clp, status);
1286
1287 out:
1288         /*
1289          * Let the state manager reestablish state
1290          * without waking other tasks yet.
1291          */
1292         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1293                 /* Wake up the next rpc task */
1294                 nfs41_end_drain_session(clp, ses);
1295                 if (status == 0)
1296                         nfs41_setup_state_renewal(clp);
1297         }
1298         return status;
1299 }
1300
1301 #else /* CONFIG_NFS_V4_1 */
1302 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1303 #endif /* CONFIG_NFS_V4_1 */
1304
1305 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1306  * on EXCHANGE_ID for v4.1
1307  */
1308 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1309 {
1310         if (nfs4_has_session(clp)) {
1311                 switch (status) {
1312                 case -NFS4ERR_DELAY:
1313                 case -NFS4ERR_CLID_INUSE:
1314                 case -EAGAIN:
1315                         break;
1316
1317                 case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1318                                          * in nfs4_exchange_id */
1319                 default:
1320                         return;
1321                 }
1322         }
1323         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1324 }
1325
1326 static void nfs4_state_manager(struct nfs_client *clp)
1327 {
1328         int status = 0;
1329
1330         /* Ensure exclusive access to NFSv4 state */
1331         for(;;) {
1332                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1333                         /* We're going to have to re-establish a clientid */
1334                         status = nfs4_reclaim_lease(clp);
1335                         if (status) {
1336                                 nfs4_set_lease_expired(clp, status);
1337                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1338                                                         &clp->cl_state))
1339                                         continue;
1340                                 if (clp->cl_cons_state ==
1341                                                         NFS_CS_SESSION_INITING)
1342                                         nfs_mark_client_ready(clp, status);
1343                                 goto out_error;
1344                         }
1345                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1346                 }
1347
1348                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1349                         status = nfs4_check_lease(clp);
1350                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1351                                 continue;
1352                         if (status < 0 && status != -NFS4ERR_CB_PATH_DOWN)
1353                                 goto out_error;
1354                 }
1355
1356                 /* Initialize or reset the session */
1357                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1358                    && nfs4_has_session(clp)) {
1359                         status = nfs4_reset_session(clp);
1360                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1361                                 continue;
1362                         if (status < 0)
1363                                 goto out_error;
1364                 }
1365
1366                 /* First recover reboot state... */
1367                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1368                         status = nfs4_do_reclaim(clp,
1369                                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1370                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1371                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1372                                 continue;
1373                         nfs4_state_end_reclaim_reboot(clp);
1374                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1375                                 continue;
1376                         if (status < 0)
1377                                 goto out_error;
1378                 }
1379
1380                 /* Now recover expired state... */
1381                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1382                         status = nfs4_do_reclaim(clp,
1383                                 nfs4_nograce_recovery_ops[clp->cl_minorversion]);
1384                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1385                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1386                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1387                                 continue;
1388                         if (status < 0)
1389                                 goto out_error;
1390                 }
1391
1392                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1393                         nfs_client_return_marked_delegations(clp);
1394                         continue;
1395                 }
1396
1397                 nfs4_clear_state_manager_bit(clp);
1398                 /* Did we race with an attempt to give us more work? */
1399                 if (clp->cl_state == 0)
1400                         break;
1401                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1402                         break;
1403         }
1404         return;
1405 out_error:
1406         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1407                         " with error %d\n", clp->cl_hostname, -status);
1408         nfs4_clear_state_manager_bit(clp);
1409 }
1410
1411 static int nfs4_run_state_manager(void *ptr)
1412 {
1413         struct nfs_client *clp = ptr;
1414
1415         allow_signal(SIGKILL);
1416         nfs4_state_manager(clp);
1417         nfs_put_client(clp);
1418         module_put_and_exit(0);
1419         return 0;
1420 }
1421
1422 /*
1423  * Local variables:
1424  *  c-basic-offset: 8
1425  * End:
1426  */