fs/nfs/nfs4state.c

   1 /*
   2  *  fs/nfs/nfs4state.c
   3  *
   4  *  Client-side XDR for NFSv4.
   5  *
   6  *  Copyright (c) 2002 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Kendrick Smith <kmsmith@umich.edu>
  10  *
  11  *  Redistribution and use in source and binary forms, with or without
  12  *  modification, are permitted provided that the following conditions
  13  *  are met:
  14  *
  15  *  1. Redistributions of source code must retain the above copyright
  16  *     notice, this list of conditions and the following disclaimer.
  17  *  2. Redistributions in binary form must reproduce the above copyright
  18  *     notice, this list of conditions and the following disclaimer in the
  19  *     documentation and/or other materials provided with the distribution.
  20  *  3. Neither the name of the University nor the names of its
  21  *     contributors may be used to endorse or promote products derived
  22  *     from this software without specific prior written permission.
  23  *
  24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  * Implementation of the NFSv4 state model.  For the time being,
  37  * this is minimal, but will be made much more complex in a
  38  * subsequent patch.
  39  */
  40
  41 #include <linux/kernel.h>
  42 #include <linux/slab.h>
  43 #include <linux/smp_lock.h>
  44 #include <linux/nfs_fs.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/kthread.h>
  47 #include <linux/module.h>
  48 #include <linux/random.h>
  49 #include <linux/workqueue.h>
  50 #include <linux/bitops.h>
  51
  52 #include "nfs4_fs.h"
  53 #include "callback.h"
  54 #include "delegation.h"
  55 #include "internal.h"
  56
  57 #define OPENOWNER_POOL_SIZE     8
  58
  59 const nfs4_stateid zero_stateid;
  60
  61 static LIST_HEAD(nfs4_clientid_list);
  62
  63 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  64 {
  65         unsigned short port;
  66         int status;
  67
  68         port = nfs_callback_tcpport;
  69         if (clp->cl_addr.ss_family == AF_INET6)
  70                 port = nfs_callback_tcpport6;
  71
  72         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred);
  73         if (status == 0)
  74                 status = nfs4_proc_setclientid_confirm(clp, cred);
  75         if (status == 0)
  76                 nfs4_schedule_state_renewal(clp);
  77         return status;
  78 }
  79
  80 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
  81 {
  82         struct rpc_cred *cred = NULL;
  83
  84         if (clp->cl_machine_cred != NULL)
  85                 cred = get_rpccred(clp->cl_machine_cred);
  86         return cred;
  87 }
  88
  89 static void nfs4_clear_machine_cred(struct nfs_client *clp)
  90 {
  91         struct rpc_cred *cred;
  92
  93         spin_lock(&clp->cl_lock);
  94         cred = clp->cl_machine_cred;
  95         clp->cl_machine_cred = NULL;
  96         spin_unlock(&clp->cl_lock);
  97         if (cred != NULL)
  98                 put_rpccred(cred);
  99 }
 100
 101 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 102 {
 103         struct nfs4_state_owner *sp;
 104         struct rb_node *pos;
 105         struct rpc_cred *cred = NULL;
 106
 107         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
 108                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 109                 if (list_empty(&sp->so_states))
 110                         continue;
 111                 cred = get_rpccred(sp->so_cred);
 112                 break;
 113         }
 114         return cred;
 115 }
 116
 117 #if defined(CONFIG_NFS_V4_1)
 118
 119 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         int max_slots;
 142
 143         if (test_and_clear_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state)) {
 144                 spin_lock(&ses->fc_slot_table.slot_tbl_lock);
 145                 max_slots = ses->fc_slot_table.max_slots;
 146                 while (max_slots--) {
 147                         struct rpc_task *task;
 148
 149                         task = rpc_wake_up_next(&ses->fc_slot_table.
 150                                                 slot_tbl_waitq);
 151                         if (!task)
 152                                 break;
 153                         rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED);
 154                 }
 155                 spin_unlock(&ses->fc_slot_table.slot_tbl_lock);
 156         }
 157 }
 158
 159 static int nfs41_begin_drain_session(struct nfs_client *clp,
 160                 struct nfs4_session *ses)
 161 {
 162         struct nfs4_slot_table *tbl = &ses->fc_slot_table;
 163
 164         spin_lock(&tbl->slot_tbl_lock);
 165         set_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state);
 166         if (tbl->highest_used_slotid != -1) {
 167                 INIT_COMPLETION(ses->complete);
 168                 spin_unlock(&tbl->slot_tbl_lock);
 169                 return wait_for_completion_interruptible(&ses->complete);
 170         }
 171         spin_unlock(&tbl->slot_tbl_lock);
 172         return 0;
 173 }
 174
 175 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 176 {
 177         int status;
 178
 179         status = nfs41_begin_drain_session(clp, clp->cl_session);
 180         if (status != 0)
 181                 goto out;
 182         status = nfs4_proc_exchange_id(clp, cred);
 183         if (status != 0)
 184                 goto out;
 185         status = nfs4_proc_create_session(clp);
 186         if (status != 0)
 187                 goto out;
 188         nfs41_end_drain_session(clp, clp->cl_session);
 189         nfs41_setup_state_renewal(clp);
 190         nfs_mark_client_ready(clp, NFS_CS_READY);
 191 out:
 192         return status;
 193 }
 194
 195 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 196 {
 197         struct rpc_cred *cred;
 198
 199         spin_lock(&clp->cl_lock);
 200         cred = nfs4_get_machine_cred_locked(clp);
 201         spin_unlock(&clp->cl_lock);
 202         return cred;
 203 }
 204
 205 #endif /* CONFIG_NFS_V4_1 */
 206
 207 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 208 {
 209         struct nfs4_state_owner *sp;
 210         struct rb_node *pos;
 211         struct rpc_cred *cred;
 212
 213         spin_lock(&clp->cl_lock);
 214         cred = nfs4_get_machine_cred_locked(clp);
 215         if (cred != NULL)
 216                 goto out;
 217         pos = rb_first(&clp->cl_state_owners);
 218         if (pos != NULL) {
 219                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
 220                 cred = get_rpccred(sp->so_cred);
 221         }
 222 out:
 223         spin_unlock(&clp->cl_lock);
 224         return cred;
 225 }
 226
 227 static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
 228                 __u64 minval, int maxbits)
 229 {
 230         struct rb_node **p, *parent;
 231         struct nfs_unique_id *pos;
 232         __u64 mask = ~0ULL;
 233
 234         if (maxbits < 64)
 235                 mask = (1ULL << maxbits) - 1ULL;
 236
 237         /* Ensure distribution is more or less flat */
 238         get_random_bytes(&new->id, sizeof(new->id));
 239         new->id &= mask;
 240         if (new->id < minval)
 241                 new->id += minval;
 242 retry:
 243         p = &root->rb_node;
 244         parent = NULL;
 245
 246         while (*p != NULL) {
 247                 parent = *p;
 248                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 249
 250                 if (new->id < pos->id)
 251                         p = &(*p)->rb_left;
 252                 else if (new->id > pos->id)
 253                         p = &(*p)->rb_right;
 254                 else
 255                         goto id_exists;
 256         }
 257         rb_link_node(&new->rb_node, parent, p);
 258         rb_insert_color(&new->rb_node, root);
 259         return;
 260 id_exists:
 261         for (;;) {
 262                 new->id++;
 263                 if (new->id < minval || (new->id & mask) != new->id) {
 264                         new->id = minval;
 265                         break;
 266                 }
 267                 parent = rb_next(parent);
 268                 if (parent == NULL)
 269                         break;
 270                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 271                 if (new->id < pos->id)
 272                         break;
 273         }
 274         goto retry;
 275 }
 276
 277 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
 278 {
 279         rb_erase(&id->rb_node, root);
 280 }
 281
 282 static struct nfs4_state_owner *
 283 nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 284 {
 285         struct nfs_client *clp = server->nfs_client;
 286         struct rb_node **p = &clp->cl_state_owners.rb_node,
 287                        *parent = NULL;
 288         struct nfs4_state_owner *sp, *res = NULL;
 289
 290         while (*p != NULL) {
 291                 parent = *p;
 292                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 293
 294                 if (server < sp->so_server) {
 295                         p = &parent->rb_left;
 296                         continue;
 297                 }
 298                 if (server > sp->so_server) {
 299                         p = &parent->rb_right;
 300                         continue;
 301                 }
 302                 if (cred < sp->so_cred)
 303                         p = &parent->rb_left;
 304                 else if (cred > sp->so_cred)
 305                         p = &parent->rb_right;
 306                 else {
 307                         atomic_inc(&sp->so_count);
 308                         res = sp;
 309                         break;
 310                 }
 311         }
 312         return res;
 313 }
 314
 315 static struct nfs4_state_owner *
 316 nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
 317 {
 318         struct rb_node **p = &clp->cl_state_owners.rb_node,
 319                        *parent = NULL;
 320         struct nfs4_state_owner *sp;
 321
 322         while (*p != NULL) {
 323                 parent = *p;
 324                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
 325
 326                 if (new->so_server < sp->so_server) {
 327                         p = &parent->rb_left;
 328                         continue;
 329                 }
 330                 if (new->so_server > sp->so_server) {
 331                         p = &parent->rb_right;
 332                         continue;
 333                 }
 334                 if (new->so_cred < sp->so_cred)
 335                         p = &parent->rb_left;
 336                 else if (new->so_cred > sp->so_cred)
 337                         p = &parent->rb_right;
 338                 else {
 339                         atomic_inc(&sp->so_count);
 340                         return sp;
 341                 }
 342         }
 343         nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
 344         rb_link_node(&new->so_client_node, parent, p);
 345         rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
 346         return new;
 347 }
 348
 349 static void
 350 nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
 351 {
 352         if (!RB_EMPTY_NODE(&sp->so_client_node))
 353                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 354         nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
 355 }
 356
 357 /*
 358  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 359  * create a new state_owner.
 360  *
 361  */
 362 static struct nfs4_state_owner *
 363 nfs4_alloc_state_owner(void)
 364 {
 365         struct nfs4_state_owner *sp;
 366
 367         sp = kzalloc(sizeof(*sp),GFP_KERNEL);
 368         if (!sp)
 369                 return NULL;
 370         spin_lock_init(&sp->so_lock);
 371         INIT_LIST_HEAD(&sp->so_states);
 372         INIT_LIST_HEAD(&sp->so_delegations);
 373         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 374         sp->so_seqid.sequence = &sp->so_sequence;
 375         spin_lock_init(&sp->so_sequence.lock);
 376         INIT_LIST_HEAD(&sp->so_sequence.list);
 377         atomic_set(&sp->so_count, 1);
 378         return sp;
 379 }
 380
 381 static void
 382 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 383 {
 384         if (!RB_EMPTY_NODE(&sp->so_client_node)) {
 385                 struct nfs_client *clp = sp->so_client;
 386
 387                 spin_lock(&clp->cl_lock);
 388                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
 389                 RB_CLEAR_NODE(&sp->so_client_node);
 390                 spin_unlock(&clp->cl_lock);
 391         }
 392 }
 393
 394 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 395 {
 396         struct nfs_client *clp = server->nfs_client;
 397         struct nfs4_state_owner *sp, *new;
 398
 399         spin_lock(&clp->cl_lock);
 400         sp = nfs4_find_state_owner(server, cred);
 401         spin_unlock(&clp->cl_lock);
 402         if (sp != NULL)
 403                 return sp;
 404         new = nfs4_alloc_state_owner();
 405         if (new == NULL)
 406                 return NULL;
 407         new->so_client = clp;
 408         new->so_server = server;
 409         new->so_cred = cred;
 410         spin_lock(&clp->cl_lock);
 411         sp = nfs4_insert_state_owner(clp, new);
 412         spin_unlock(&clp->cl_lock);
 413         if (sp == new)
 414                 get_rpccred(cred);
 415         else {
 416                 rpc_destroy_wait_queue(&new->so_sequence.wait);
 417                 kfree(new);
 418         }
 419         return sp;
 420 }
 421
 422 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 423 {
 424         struct nfs_client *clp = sp->so_client;
 425         struct rpc_cred *cred = sp->so_cred;
 426
 427         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 428                 return;
 429         nfs4_remove_state_owner(clp, sp);
 430         spin_unlock(&clp->cl_lock);
 431         rpc_destroy_wait_queue(&sp->so_sequence.wait);
 432         put_rpccred(cred);
 433         kfree(sp);
 434 }
 435
 436 static struct nfs4_state *
 437 nfs4_alloc_open_state(void)
 438 {
 439         struct nfs4_state *state;
 440
 441         state = kzalloc(sizeof(*state), GFP_KERNEL);
 442         if (!state)
 443                 return NULL;
 444         atomic_set(&state->count, 1);
 445         INIT_LIST_HEAD(&state->lock_states);
 446         spin_lock_init(&state->state_lock);
 447         seqlock_init(&state->seqlock);
 448         return state;
 449 }
 450
 451 void
 452 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 453 {
 454         if (state->state == fmode)
 455                 return;
 456         /* NB! List reordering - see the reclaim code for why.  */
 457         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 458                 if (fmode & FMODE_WRITE)
 459                         list_move(&state->open_states, &state->owner->so_states);
 460                 else
 461                         list_move_tail(&state->open_states, &state->owner->so_states);
 462         }
 463         state->state = fmode;
 464 }
 465
 466 static struct nfs4_state *
 467 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 468 {
 469         struct nfs_inode *nfsi = NFS_I(inode);
 470         struct nfs4_state *state;
 471
 472         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 473                 if (state->owner != owner)
 474                         continue;
 475                 if (atomic_inc_not_zero(&state->count))
 476                         return state;
 477         }
 478         return NULL;
 479 }
 480
 481 static void
 482 nfs4_free_open_state(struct nfs4_state *state)
 483 {
 484         kfree(state);
 485 }
 486
 487 struct nfs4_state *
 488 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 489 {
 490         struct nfs4_state *state, *new;
 491         struct nfs_inode *nfsi = NFS_I(inode);
 492
 493         spin_lock(&inode->i_lock);
 494         state = __nfs4_find_state_byowner(inode, owner);
 495         spin_unlock(&inode->i_lock);
 496         if (state)
 497                 goto out;
 498         new = nfs4_alloc_open_state();
 499         spin_lock(&owner->so_lock);
 500         spin_lock(&inode->i_lock);
 501         state = __nfs4_find_state_byowner(inode, owner);
 502         if (state == NULL && new != NULL) {
 503                 state = new;
 504                 state->owner = owner;
 505                 atomic_inc(&owner->so_count);
 506                 list_add(&state->inode_states, &nfsi->open_states);
 507                 state->inode = igrab(inode);
 508                 spin_unlock(&inode->i_lock);
 509                 /* Note: The reclaim code dictates that we add stateless
 510                  * and read-only stateids to the end of the list */
 511                 list_add_tail(&state->open_states, &owner->so_states);
 512                 spin_unlock(&owner->so_lock);
 513         } else {
 514                 spin_unlock(&inode->i_lock);
 515                 spin_unlock(&owner->so_lock);
 516                 if (new)
 517                         nfs4_free_open_state(new);
 518         }
 519 out:
 520         return state;
 521 }
 522
 523 void nfs4_put_open_state(struct nfs4_state *state)
 524 {
 525         struct inode *inode = state->inode;
 526         struct nfs4_state_owner *owner = state->owner;
 527
 528         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 529                 return;
 530         spin_lock(&inode->i_lock);
 531         list_del(&state->inode_states);
 532         list_del(&state->open_states);
 533         spin_unlock(&inode->i_lock);
 534         spin_unlock(&owner->so_lock);
 535         iput(inode);
 536         nfs4_free_open_state(state);
 537         nfs4_put_state_owner(owner);
 538 }
 539
 540 /*
 541  * Close the current file.
 542  */
 543 static void __nfs4_close(struct path *path, struct nfs4_state *state, fmode_t fmode, int wait)
 544 {
 545         struct nfs4_state_owner *owner = state->owner;
 546         int call_close = 0;
 547         fmode_t newstate;
 548
 549         atomic_inc(&owner->so_count);
 550         /* Protect against nfs4_find_state() */
 551         spin_lock(&owner->so_lock);
 552         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 553                 case FMODE_READ:
 554                         state->n_rdonly--;
 555                         break;
 556                 case FMODE_WRITE:
 557                         state->n_wronly--;
 558                         break;
 559                 case FMODE_READ|FMODE_WRITE:
 560                         state->n_rdwr--;
 561         }
 562         newstate = FMODE_READ|FMODE_WRITE;
 563         if (state->n_rdwr == 0) {
 564                 if (state->n_rdonly == 0) {
 565                         newstate &= ~FMODE_READ;
 566                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 567                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 568                 }
 569                 if (state->n_wronly == 0) {
 570                         newstate &= ~FMODE_WRITE;
 571                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 572                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 573                 }
 574                 if (newstate == 0)
 575                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 576         }
 577         nfs4_state_set_mode_locked(state, newstate);
 578         spin_unlock(&owner->so_lock);
 579
 580         if (!call_close) {
 581                 nfs4_put_open_state(state);
 582                 nfs4_put_state_owner(owner);
 583         } else
 584                 nfs4_do_close(path, state, wait);
 585 }
 586
 587 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
 588 {
 589         __nfs4_close(path, state, fmode, 0);
 590 }
 591
 592 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
 593 {
 594         __nfs4_close(path, state, fmode, 1);
 595 }
 596
 597 /*
 598  * Search the state->lock_states for an existing lock_owner
 599  * that is compatible with current->files
 600  */
 601 static struct nfs4_lock_state *
 602 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 603 {
 604         struct nfs4_lock_state *pos;
 605         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 606                 if (pos->ls_owner != fl_owner)
 607                         continue;
 608                 atomic_inc(&pos->ls_count);
 609                 return pos;
 610         }
 611         return NULL;
 612 }
 613
 614 /*
 615  * Return a compatible lock_state. If no initialized lock_state structure
 616  * exists, return an uninitialized one.
 617  *
 618  */
 619 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 620 {
 621         struct nfs4_lock_state *lsp;
 622         struct nfs_client *clp = state->owner->so_client;
 623
 624         lsp = kzalloc(sizeof(*lsp), GFP_KERNEL);
 625         if (lsp == NULL)
 626                 return NULL;
 627         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 628         spin_lock_init(&lsp->ls_sequence.lock);
 629         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 630         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 631         atomic_set(&lsp->ls_count, 1);
 632         lsp->ls_state = state;
 633         lsp->ls_owner = fl_owner;
 634         spin_lock(&clp->cl_lock);
 635         nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
 636         spin_unlock(&clp->cl_lock);
 637         INIT_LIST_HEAD(&lsp->ls_locks);
 638         return lsp;
 639 }
 640
 641 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 642 {
 643         struct nfs_client *clp = lsp->ls_state->owner->so_client;
 644
 645         spin_lock(&clp->cl_lock);
 646         nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
 647         spin_unlock(&clp->cl_lock);
 648         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 649         kfree(lsp);
 650 }
 651
 652 /*
 653  * Return a compatible lock_state. If no initialized lock_state structure
 654  * exists, return an uninitialized one.
 655  *
 656  */
 657 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 658 {
 659         struct nfs4_lock_state *lsp, *new = NULL;
 660
 661         for(;;) {
 662                 spin_lock(&state->state_lock);
 663                 lsp = __nfs4_find_lock_state(state, owner);
 664                 if (lsp != NULL)
 665                         break;
 666                 if (new != NULL) {
 667                         list_add(&new->ls_locks, &state->lock_states);
 668                         set_bit(LK_STATE_IN_USE, &state->flags);
 669                         lsp = new;
 670                         new = NULL;
 671                         break;
 672                 }
 673                 spin_unlock(&state->state_lock);
 674                 new = nfs4_alloc_lock_state(state, owner);
 675                 if (new == NULL)
 676                         return NULL;
 677         }
 678         spin_unlock(&state->state_lock);
 679         if (new != NULL)
 680                 nfs4_free_lock_state(new);
 681         return lsp;
 682 }
 683
 684 /*
 685  * Release reference to lock_state, and free it if we see that
 686  * it is no longer in use
 687  */
 688 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 689 {
 690         struct nfs4_state *state;
 691
 692         if (lsp == NULL)
 693                 return;
 694         state = lsp->ls_state;
 695         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 696                 return;
 697         list_del(&lsp->ls_locks);
 698         if (list_empty(&state->lock_states))
 699                 clear_bit(LK_STATE_IN_USE, &state->flags);
 700         spin_unlock(&state->state_lock);
 701         nfs4_free_lock_state(lsp);
 702 }
 703
 704 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 705 {
 706         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 707
 708         dst->fl_u.nfs4_fl.owner = lsp;
 709         atomic_inc(&lsp->ls_count);
 710 }
 711
 712 static void nfs4_fl_release_lock(struct file_lock *fl)
 713 {
 714         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 715 }
 716
 717 static const struct file_lock_operations nfs4_fl_lock_ops = {
 718         .fl_copy_lock = nfs4_fl_copy_lock,
 719         .fl_release_private = nfs4_fl_release_lock,
 720 };
 721
 722 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 723 {
 724         struct nfs4_lock_state *lsp;
 725
 726         if (fl->fl_ops != NULL)
 727                 return 0;
 728         lsp = nfs4_get_lock_state(state, fl->fl_owner);
 729         if (lsp == NULL)
 730                 return -ENOMEM;
 731         fl->fl_u.nfs4_fl.owner = lsp;
 732         fl->fl_ops = &nfs4_fl_lock_ops;
 733         return 0;
 734 }
 735
 736 /*
 737  * Byte-range lock aware utility to initialize the stateid of read/write
 738  * requests.
 739  */
 740 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
 741 {
 742         struct nfs4_lock_state *lsp;
 743         int seq;
 744
 745         do {
 746                 seq = read_seqbegin(&state->seqlock);
 747                 memcpy(dst, &state->stateid, sizeof(*dst));
 748         } while (read_seqretry(&state->seqlock, seq));
 749         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 750                 return;
 751
 752         spin_lock(&state->state_lock);
 753         lsp = __nfs4_find_lock_state(state, fl_owner);
 754         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 755                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 756         spin_unlock(&state->state_lock);
 757         nfs4_put_lock_state(lsp);
 758 }
 759
 760 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
 761 {
 762         struct nfs_seqid *new;
 763
 764         new = kmalloc(sizeof(*new), GFP_KERNEL);
 765         if (new != NULL) {
 766                 new->sequence = counter;
 767                 INIT_LIST_HEAD(&new->list);
 768         }
 769         return new;
 770 }
 771
 772 void nfs_free_seqid(struct nfs_seqid *seqid)
 773 {
 774         if (!list_empty(&seqid->list)) {
 775                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 776
 777                 spin_lock(&sequence->lock);
 778                 list_del(&seqid->list);
 779                 spin_unlock(&sequence->lock);
 780                 rpc_wake_up(&sequence->wait);
 781         }
 782         kfree(seqid);
 783 }
 784
 785 /*
 786  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 787  * failed with a seqid incrementing error -
 788  * see comments nfs_fs.h:seqid_mutating_error()
 789  */
 790 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 791 {
 792         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 793         switch (status) {
 794                 case 0:
 795                         break;
 796                 case -NFS4ERR_BAD_SEQID:
 797                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
 798                                 return;
 799                         printk(KERN_WARNING "NFS: v4 server returned a bad"
 800                                         " sequence-id error on an"
 801                                         " unconfirmed sequence %p!\n",
 802                                         seqid->sequence);
 803                 case -NFS4ERR_STALE_CLIENTID:
 804                 case -NFS4ERR_STALE_STATEID:
 805                 case -NFS4ERR_BAD_STATEID:
 806                 case -NFS4ERR_BADXDR:
 807                 case -NFS4ERR_RESOURCE:
 808                 case -NFS4ERR_NOFILEHANDLE:
 809                         /* Non-seqid mutating errors */
 810                         return;
 811         };
 812         /*
 813          * Note: no locking needed as we are guaranteed to be first
 814          * on the sequence list
 815          */
 816         seqid->sequence->counter++;
 817 }
 818
 819 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
 820 {
 821         struct nfs4_state_owner *sp = container_of(seqid->sequence,
 822                                         struct nfs4_state_owner, so_seqid);
 823         struct nfs_server *server = sp->so_server;
 824
 825         if (status == -NFS4ERR_BAD_SEQID)
 826                 nfs4_drop_state_owner(sp);
 827         if (!nfs4_has_session(server->nfs_client))
 828                 nfs_increment_seqid(status, seqid);
 829 }
 830
 831 /*
 832  * Increment the seqid if the LOCK/LOCKU succeeded, or
 833  * failed with a seqid incrementing error -
 834  * see comments nfs_fs.h:seqid_mutating_error()
 835  */
 836 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
 837 {
 838         nfs_increment_seqid(status, seqid);
 839 }
 840
 841 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
 842 {
 843         struct rpc_sequence *sequence = seqid->sequence->sequence;
 844         int status = 0;
 845
 846         spin_lock(&sequence->lock);
 847         if (list_empty(&seqid->list))
 848                 list_add_tail(&seqid->list, &sequence->list);
 849         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
 850                 goto unlock;
 851         rpc_sleep_on(&sequence->wait, task, NULL);
 852         status = -EAGAIN;
 853 unlock:
 854         spin_unlock(&sequence->lock);
 855         return status;
 856 }
 857
 858 static int nfs4_run_state_manager(void *);
 859
 860 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
 861 {
 862         smp_mb__before_clear_bit();
 863         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
 864         smp_mb__after_clear_bit();
 865         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
 866         rpc_wake_up(&clp->cl_rpcwaitq);
 867 }
 868
 869 /*
 870  * Schedule the nfs_client asynchronous state management routine
 871  */
 872 void nfs4_schedule_state_manager(struct nfs_client *clp)
 873 {
 874         struct task_struct *task;
 875
 876         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
 877                 return;
 878         __module_get(THIS_MODULE);
 879         atomic_inc(&clp->cl_count);
 880         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
 881                                 rpc_peeraddr2str(clp->cl_rpcclient,
 882                                                         RPC_DISPLAY_ADDR));
 883         if (!IS_ERR(task))
 884                 return;
 885         nfs4_clear_state_manager_bit(clp);
 886         nfs_put_client(clp);
 887         module_put(THIS_MODULE);
 888 }
 889
 890 /*
 891  * Schedule a state recovery attempt
 892  */
 893 void nfs4_schedule_state_recovery(struct nfs_client *clp)
 894 {
 895         if (!clp)
 896                 return;
 897         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
 898                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
 899         nfs4_schedule_state_manager(clp);
 900 }
 901
 902 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
 903 {
 904
 905         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 906         /* Don't recover state that expired before the reboot */
 907         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
 908                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 909                 return 0;
 910         }
 911         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
 912         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
 913         return 1;
 914 }
 915
 916 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
 917 {
 918         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
 919         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 920         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
 921         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
 922         return 1;
 923 }
 924
 925 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
 926 {
 927         struct inode *inode = state->inode;
 928         struct nfs_inode *nfsi = NFS_I(inode);
 929         struct file_lock *fl;
 930         int status = 0;
 931
 932         if (inode->i_flock == NULL)
 933                 return 0;
 934
 935         /* Guard against delegation returns and new lock/unlock calls */
 936         down_write(&nfsi->rwsem);
 937         /* Protect inode->i_flock using the BKL */
 938         lock_kernel();
 939         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
 940                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
 941                         continue;
 942                 if (nfs_file_open_context(fl->fl_file)->state != state)
 943                         continue;
 944                 unlock_kernel();
 945                 status = ops->recover_lock(state, fl);
 946                 switch (status) {
 947                         case 0:
 948                                 break;
 949                         case -ESTALE:
 950                         case -NFS4ERR_ADMIN_REVOKED:
 951                         case -NFS4ERR_STALE_STATEID:
 952                         case -NFS4ERR_BAD_STATEID:
 953                         case -NFS4ERR_EXPIRED:
 954                         case -NFS4ERR_NO_GRACE:
 955                         case -NFS4ERR_STALE_CLIENTID:
 956                         case -NFS4ERR_BADSESSION:
 957                         case -NFS4ERR_BADSLOT:
 958                         case -NFS4ERR_BAD_HIGH_SLOT:
 959                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 960                                 goto out;
 961                         default:
 962                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 963                                                 __func__, status);
 964                         case -ENOMEM:
 965                         case -NFS4ERR_DENIED:
 966                         case -NFS4ERR_RECLAIM_BAD:
 967                         case -NFS4ERR_RECLAIM_CONFLICT:
 968                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
 969                                 status = 0;
 970                 }
 971                 lock_kernel();
 972         }
 973         unlock_kernel();
 974 out:
 975         up_write(&nfsi->rwsem);
 976         return status;
 977 }
 978
 979 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
 980 {
 981         struct nfs4_state *state;
 982         struct nfs4_lock_state *lock;
 983         int status = 0;
 984
 985         /* Note: we rely on the sp->so_states list being ordered
 986          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
 987          * states first.
 988          * This is needed to ensure that the server won't give us any
 989          * read delegations that we have to return if, say, we are
 990          * recovering after a network partition or a reboot from a
 991          * server that doesn't support a grace period.
 992          */
 993 restart:
 994         spin_lock(&sp->so_lock);
 995         list_for_each_entry(state, &sp->so_states, open_states) {
 996                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
 997                         continue;
 998                 if (state->state == 0)
 999                         continue;
1000                 atomic_inc(&state->count);
1001                 spin_unlock(&sp->so_lock);
1002                 status = ops->recover_open(sp, state);
1003                 if (status >= 0) {
1004                         status = nfs4_reclaim_locks(state, ops);
1005                         if (status >= 0) {
1006                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1007                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1008                                                 printk("%s: Lock reclaim failed!\n",
1009                                                         __func__);
1010                                 }
1011                                 nfs4_put_open_state(state);
1012                                 goto restart;
1013                         }
1014                 }
1015                 switch (status) {
1016                         default:
1017                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1018                                                 __func__, status);
1019                         case -ENOENT:
1020                         case -ENOMEM:
1021                         case -ESTALE:
1022                                 /*
1023                                  * Open state on this file cannot be recovered
1024                                  * All we can do is revert to using the zero stateid.
1025                                  */
1026                                 memset(state->stateid.data, 0,
1027                                         sizeof(state->stateid.data));
1028                                 /* Mark the file as being 'closed' */
1029                                 state->state = 0;
1030                                 break;
1031                         case -NFS4ERR_ADMIN_REVOKED:
1032                         case -NFS4ERR_STALE_STATEID:
1033                         case -NFS4ERR_BAD_STATEID:
1034                         case -NFS4ERR_RECLAIM_BAD:
1035                         case -NFS4ERR_RECLAIM_CONFLICT:
1036                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
1037                                 break;
1038                         case -NFS4ERR_EXPIRED:
1039                         case -NFS4ERR_NO_GRACE:
1040                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
1041                         case -NFS4ERR_STALE_CLIENTID:
1042                         case -NFS4ERR_BADSESSION:
1043                         case -NFS4ERR_BADSLOT:
1044                         case -NFS4ERR_BAD_HIGH_SLOT:
1045                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1046                                 goto out_err;
1047                 }
1048                 nfs4_put_open_state(state);
1049                 goto restart;
1050         }
1051         spin_unlock(&sp->so_lock);
1052         return 0;
1053 out_err:
1054         nfs4_put_open_state(state);
1055         return status;
1056 }
1057
1058 static void nfs4_clear_open_state(struct nfs4_state *state)
1059 {
1060         struct nfs4_lock_state *lock;
1061
1062         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1063         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1064         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1065         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1066         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1067                 lock->ls_seqid.flags = 0;
1068                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1069         }
1070 }
1071
1072 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1073 {
1074         struct nfs4_state_owner *sp;
1075         struct rb_node *pos;
1076         struct nfs4_state *state;
1077
1078         /* Reset all sequence ids to zero */
1079         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1080                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1081                 sp->so_seqid.flags = 0;
1082                 spin_lock(&sp->so_lock);
1083                 list_for_each_entry(state, &sp->so_states, open_states) {
1084                         if (mark_reclaim(clp, state))
1085                                 nfs4_clear_open_state(state);
1086                 }
1087                 spin_unlock(&sp->so_lock);
1088         }
1089 }
1090
1091 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1092 {
1093         /* Mark all delegations for reclaim */
1094         nfs_delegation_mark_reclaim(clp);
1095         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1096 }
1097
1098 static void nfs4_reclaim_complete(struct nfs_client *clp,
1099                                  const struct nfs4_state_recovery_ops *ops)
1100 {
1101         /* Notify the server we're done reclaiming our state */
1102         if (ops->reclaim_complete)
1103                 (void)ops->reclaim_complete(clp);
1104 }
1105
1106 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1107 {
1108         struct nfs4_state_owner *sp;
1109         struct rb_node *pos;
1110         struct nfs4_state *state;
1111
1112         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1113                 return;
1114
1115         nfs4_reclaim_complete(clp,
1116                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1117
1118         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1119                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1120                 spin_lock(&sp->so_lock);
1121                 list_for_each_entry(state, &sp->so_states, open_states) {
1122                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
1123                                 continue;
1124                         nfs4_state_mark_reclaim_nograce(clp, state);
1125                 }
1126                 spin_unlock(&sp->so_lock);
1127         }
1128
1129         nfs_delegation_reap_unclaimed(clp);
1130 }
1131
1132 static void nfs_delegation_clear_all(struct nfs_client *clp)
1133 {
1134         nfs_delegation_mark_reclaim(clp);
1135         nfs_delegation_reap_unclaimed(clp);
1136 }
1137
1138 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1139 {
1140         nfs_delegation_clear_all(clp);
1141         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1142 }
1143
1144 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1145 {
1146         switch (error) {
1147                 case -NFS4ERR_CB_PATH_DOWN:
1148                         nfs_handle_cb_pathdown(clp);
1149                         return 0;
1150                 case -NFS4ERR_NO_GRACE:
1151                         nfs4_state_end_reclaim_reboot(clp);
1152                         return 0;
1153                 case -NFS4ERR_STALE_CLIENTID:
1154                 case -NFS4ERR_LEASE_MOVED:
1155                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1156                         nfs4_state_end_reclaim_reboot(clp);
1157                         nfs4_state_start_reclaim_reboot(clp);
1158                         break;
1159                 case -NFS4ERR_EXPIRED:
1160                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1161                         nfs4_state_start_reclaim_nograce(clp);
1162                         break;
1163                 case -NFS4ERR_BADSESSION:
1164                 case -NFS4ERR_BADSLOT:
1165                 case -NFS4ERR_BAD_HIGH_SLOT:
1166                 case -NFS4ERR_DEADSESSION:
1167                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1168                 case -NFS4ERR_SEQ_FALSE_RETRY:
1169                 case -NFS4ERR_SEQ_MISORDERED:
1170                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1171                         /* Zero session reset errors */
1172                         return 0;
1173         }
1174         return error;
1175 }
1176
1177 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1178 {
1179         struct rb_node *pos;
1180         int status = 0;
1181
1182 restart:
1183         spin_lock(&clp->cl_lock);
1184         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1185                 struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1186                 if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
1187                         continue;
1188                 atomic_inc(&sp->so_count);
1189                 spin_unlock(&clp->cl_lock);
1190                 status = nfs4_reclaim_open_state(sp, ops);
1191                 if (status < 0) {
1192                         set_bit(ops->owner_flag_bit, &sp->so_flags);
1193                         nfs4_put_state_owner(sp);
1194                         return nfs4_recovery_handle_error(clp, status);
1195                 }
1196                 nfs4_put_state_owner(sp);
1197                 goto restart;
1198         }
1199         spin_unlock(&clp->cl_lock);
1200         return status;
1201 }
1202
1203 static int nfs4_check_lease(struct nfs_client *clp)
1204 {
1205         struct rpc_cred *cred;
1206         struct nfs4_state_maintenance_ops *ops =
1207                 nfs4_state_renewal_ops[clp->cl_minorversion];
1208         int status = -NFS4ERR_EXPIRED;
1209
1210         /* Is the client already known to have an expired lease? */
1211         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1212                 return 0;
1213         spin_lock(&clp->cl_lock);
1214         cred = ops->get_state_renewal_cred_locked(clp);
1215         spin_unlock(&clp->cl_lock);
1216         if (cred == NULL) {
1217                 cred = nfs4_get_setclientid_cred(clp);
1218                 if (cred == NULL)
1219                         goto out;
1220         }
1221         status = ops->renew_lease(clp, cred);
1222         put_rpccred(cred);
1223 out:
1224         return nfs4_recovery_handle_error(clp, status);
1225 }
1226
1227 static int nfs4_reclaim_lease(struct nfs_client *clp)
1228 {
1229         struct rpc_cred *cred;
1230         struct nfs4_state_recovery_ops *ops =
1231                 nfs4_reboot_recovery_ops[clp->cl_minorversion];
1232         int status = -ENOENT;
1233
1234         cred = ops->get_clid_cred(clp);
1235         if (cred != NULL) {
1236                 status = ops->establish_clid(clp, cred);
1237                 put_rpccred(cred);
1238                 /* Handle case where the user hasn't set up machine creds */
1239                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1240                         nfs4_clear_machine_cred(clp);
1241                         status = -EAGAIN;
1242                 }
1243                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1244                         status = -EPROTONOSUPPORT;
1245         }
1246         return status;
1247 }
1248
1249 #ifdef CONFIG_NFS_V4_1
1250 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1251 {
1252         if (!flags)
1253                 return;
1254         else if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED) {
1255                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1256                 nfs4_state_start_reclaim_reboot(clp);
1257                 nfs4_schedule_state_recovery(clp);
1258         } else if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1259                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1260                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1261                             SEQ4_STATUS_RECALLABLE_STATE_REVOKED |
1262                             SEQ4_STATUS_LEASE_MOVED)) {
1263                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1264                 nfs4_state_start_reclaim_nograce(clp);
1265                 nfs4_schedule_state_recovery(clp);
1266         } else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1267                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1268                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1269                 nfs_expire_all_delegations(clp);
1270 }
1271
1272 static int nfs4_reset_session(struct nfs_client *clp)
1273 {
1274         struct nfs4_session *ses = clp->cl_session;
1275         int status;
1276
1277         status = nfs41_begin_drain_session(clp, ses);
1278         if (status != 0)
1279                 return status;
1280
1281         status = nfs4_proc_destroy_session(clp->cl_session);
1282         if (status && status != -NFS4ERR_BADSESSION &&
1283             status != -NFS4ERR_DEADSESSION) {
1284                 status = nfs4_recovery_handle_error(clp, status);
1285                 goto out;
1286         }
1287
1288         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1289         status = nfs4_proc_create_session(clp);
1290         if (status)
1291                 status = nfs4_recovery_handle_error(clp, status);
1292
1293 out:
1294         /*
1295          * Let the state manager reestablish state
1296          * without waking other tasks yet.
1297          */
1298         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1299                 /* Wake up the next rpc task */
1300                 nfs41_end_drain_session(clp, ses);
1301                 if (status == 0)
1302                         nfs41_setup_state_renewal(clp);
1303         }
1304         return status;
1305 }
1306
1307 #else /* CONFIG_NFS_V4_1 */
1308 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1309 #endif /* CONFIG_NFS_V4_1 */
1310
1311 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1312  * on EXCHANGE_ID for v4.1
1313  */
1314 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1315 {
1316         if (nfs4_has_session(clp)) {
1317                 switch (status) {
1318                 case -NFS4ERR_DELAY:
1319                 case -NFS4ERR_CLID_INUSE:
1320                 case -EAGAIN:
1321                         break;
1322
1323                 case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1324                                          * in nfs4_exchange_id */
1325                 default:
1326                         return;
1327                 }
1328         }
1329         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1330 }
1331
1332 static void nfs4_state_manager(struct nfs_client *clp)
1333 {
1334         int status = 0;
1335
1336         /* Ensure exclusive access to NFSv4 state */
1337         for(;;) {
1338                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1339                         /* We're going to have to re-establish a clientid */
1340                         status = nfs4_reclaim_lease(clp);
1341                         if (status) {
1342                                 nfs4_set_lease_expired(clp, status);
1343                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1344                                                         &clp->cl_state))
1345                                         continue;
1346                                 if (clp->cl_cons_state ==
1347                                                         NFS_CS_SESSION_INITING)
1348                                         nfs_mark_client_ready(clp, status);
1349                                 goto out_error;
1350                         }
1351                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1352                         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1353                 }
1354
1355                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1356                         status = nfs4_check_lease(clp);
1357                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1358                                 continue;
1359                         if (status < 0 && status != -NFS4ERR_CB_PATH_DOWN)
1360                                 goto out_error;
1361                 }
1362
1363                 /* Initialize or reset the session */
1364                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1365                    && nfs4_has_session(clp)) {
1366                         status = nfs4_reset_session(clp);
1367                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1368                                 continue;
1369                         if (status < 0)
1370                                 goto out_error;
1371                 }
1372
1373                 /* First recover reboot state... */
1374                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1375                         status = nfs4_do_reclaim(clp,
1376                                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1377                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1378                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1379                                 continue;
1380                         nfs4_state_end_reclaim_reboot(clp);
1381                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1382                                 continue;
1383                         if (status < 0)
1384                                 goto out_error;
1385                 }
1386
1387                 /* Now recover expired state... */
1388                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1389                         status = nfs4_do_reclaim(clp,
1390                                 nfs4_nograce_recovery_ops[clp->cl_minorversion]);
1391                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1392                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1393                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1394                                 continue;
1395                         if (status < 0)
1396                                 goto out_error;
1397                 }
1398
1399                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1400                         nfs_client_return_marked_delegations(clp);
1401                         continue;
1402                 }
1403
1404                 nfs4_clear_state_manager_bit(clp);
1405                 /* Did we race with an attempt to give us more work? */
1406                 if (clp->cl_state == 0)
1407                         break;
1408                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1409                         break;
1410         }
1411         return;
1412 out_error:
1413         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1414                         " with error %d\n", clp->cl_hostname, -status);
1415         nfs4_clear_state_manager_bit(clp);
1416 }
1417
1418 static int nfs4_run_state_manager(void *ptr)
1419 {
1420         struct nfs_client *clp = ptr;
1421
1422         allow_signal(SIGKILL);
1423         nfs4_state_manager(clp);
1424         nfs_put_client(clp);
1425         module_put_and_exit(0);
1426         return 0;
1427 }
1428
1429 /*
1430  * Local variables:
1431  *  c-basic-offset: 8
1432  * End:
1433  */