fs/nfs/nfs4state.c

   1 /*
   2  *  fs/nfs/nfs4state.c
   3  *
   4  *  Client-side XDR for NFSv4.
   5  *
   6  *  Copyright (c) 2002 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Kendrick Smith <kmsmith@umich.edu>
  10  *
  11  *  Redistribution and use in source and binary forms, with or without
  12  *  modification, are permitted provided that the following conditions
  13  *  are met:
  14  *
  15  *  1. Redistributions of source code must retain the above copyright
  16  *     notice, this list of conditions and the following disclaimer.
  17  *  2. Redistributions in binary form must reproduce the above copyright
  18  *     notice, this list of conditions and the following disclaimer in the
  19  *     documentation and/or other materials provided with the distribution.
  20  *  3. Neither the name of the University nor the names of its
  21  *     contributors may be used to endorse or promote products derived
  22  *     from this software without specific prior written permission.
  23  *
  24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  * Implementation of the NFSv4 state model.  For the time being,
  37  * this is minimal, but will be made much more complex in a
  38  * subsequent patch.
  39  */
  40
  41 #include <linux/kernel.h>
  42 #include <linux/slab.h>
  43 #include <linux/fs.h>
  44 #include <linux/nfs_fs.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/kthread.h>
  47 #include <linux/module.h>
  48 #include <linux/random.h>
  49 #include <linux/ratelimit.h>
  50 #include <linux/workqueue.h>
  51 #include <linux/bitops.h>
  52
  53 #include "nfs4_fs.h"
  54 #include "callback.h"
  55 #include "delegation.h"
  56 #include "internal.h"
  57 #include "pnfs.h"
  58
  59 #define OPENOWNER_POOL_SIZE     8
  60
  61 const nfs4_stateid zero_stateid;
  62
  63 static LIST_HEAD(nfs4_clientid_list);
  64
  65 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  66 {
  67         struct nfs4_setclientid_res clid = {
  68                 .clientid = clp->cl_clientid,
  69                 .confirm = clp->cl_confirm,
  70         };
  71         unsigned short port;
  72         int status;
  73
  74         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
  75                 goto do_confirm;
  76         port = nfs_callback_tcpport;
  77         if (clp->cl_addr.ss_family == AF_INET6)
  78                 port = nfs_callback_tcpport6;
  79
  80         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
  81         if (status != 0)
  82                 goto out;
  83         clp->cl_clientid = clid.clientid;
  84         clp->cl_confirm = clid.confirm;
  85         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  86 do_confirm:
  87         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
  88         if (status != 0)
  89                 goto out;
  90         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  91         nfs4_schedule_state_renewal(clp);
  92 out:
  93         return status;
  94 }
  95
  96 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
  97 {
  98         struct rpc_cred *cred = NULL;
  99
 100         if (clp->cl_machine_cred != NULL)
 101                 cred = get_rpccred(clp->cl_machine_cred);
 102         return cred;
 103 }
 104
 105 static void nfs4_clear_machine_cred(struct nfs_client *clp)
 106 {
 107         struct rpc_cred *cred;
 108
 109         spin_lock(&clp->cl_lock);
 110         cred = clp->cl_machine_cred;
 111         clp->cl_machine_cred = NULL;
 112         spin_unlock(&clp->cl_lock);
 113         if (cred != NULL)
 114                 put_rpccred(cred);
 115 }
 116
 117 static struct rpc_cred *
 118 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 119 {
 120         struct rpc_cred *cred = NULL;
 121         struct nfs4_state_owner *sp;
 122         struct rb_node *pos;
 123
 124         for (pos = rb_first(&server->state_owners);
 125              pos != NULL;
 126              pos = rb_next(pos)) {
 127                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 128                 if (list_empty(&sp->so_states))
 129                         continue;
 130                 cred = get_rpccred(sp->so_cred);
 131                 break;
 132         }
 133         return cred;
 134 }
 135
 136 /**
 137  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
 138  * @clp: client state handle
 139  *
 140  * Returns an rpc_cred with reference count bumped, or NULL.
 141  * Caller must hold clp->cl_lock.
 142  */
 143 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 144 {
 145         struct rpc_cred *cred = NULL;
 146         struct nfs_server *server;
 147
 148         rcu_read_lock();
 149         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 150                 cred = nfs4_get_renew_cred_server_locked(server);
 151                 if (cred != NULL)
 152                         break;
 153         }
 154         rcu_read_unlock();
 155         return cred;
 156 }
 157
 158 #if defined(CONFIG_NFS_V4_1)
 159
 160 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 161 {
 162         int status;
 163         struct nfs_fsinfo fsinfo;
 164
 165         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
 166                 nfs4_schedule_state_renewal(clp);
 167                 return 0;
 168         }
 169
 170         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 171         if (status == 0) {
 172                 /* Update lease time and schedule renewal */
 173                 spin_lock(&clp->cl_lock);
 174                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 175                 clp->cl_last_renewal = jiffies;
 176                 spin_unlock(&clp->cl_lock);
 177
 178                 nfs4_schedule_state_renewal(clp);
 179         }
 180
 181         return status;
 182 }
 183
 184 /*
 185  * Back channel returns NFS4ERR_DELAY for new requests when
 186  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
 187  * is ended.
 188  */
 189 static void nfs4_end_drain_session(struct nfs_client *clp)
 190 {
 191         struct nfs4_session *ses = clp->cl_session;
 192         int max_slots;
 193
 194         if (ses == NULL)
 195                 return;
 196         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
 197                 spin_lock(&ses->fc_slot_table.slot_tbl_lock);
 198                 max_slots = ses->fc_slot_table.max_slots;
 199                 while (max_slots--) {
 200                         struct rpc_task *task;
 201
 202                         task = rpc_wake_up_next(&ses->fc_slot_table.
 203                                                 slot_tbl_waitq);
 204                         if (!task)
 205                                 break;
 206                         rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED);
 207                 }
 208                 spin_unlock(&ses->fc_slot_table.slot_tbl_lock);
 209         }
 210 }
 211
 212 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
 213 {
 214         spin_lock(&tbl->slot_tbl_lock);
 215         if (tbl->highest_used_slotid != -1) {
 216                 INIT_COMPLETION(tbl->complete);
 217                 spin_unlock(&tbl->slot_tbl_lock);
 218                 return wait_for_completion_interruptible(&tbl->complete);
 219         }
 220         spin_unlock(&tbl->slot_tbl_lock);
 221         return 0;
 222 }
 223
 224 static int nfs4_begin_drain_session(struct nfs_client *clp)
 225 {
 226         struct nfs4_session *ses = clp->cl_session;
 227         int ret = 0;
 228
 229         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
 230         /* back channel */
 231         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
 232         if (ret)
 233                 return ret;
 234         /* fore channel */
 235         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
 236 }
 237
 238 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 239 {
 240         int status;
 241
 242         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 243                 goto do_confirm;
 244         nfs4_begin_drain_session(clp);
 245         status = nfs4_proc_exchange_id(clp, cred);
 246         if (status != 0)
 247                 goto out;
 248         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 249 do_confirm:
 250         status = nfs4_proc_create_session(clp);
 251         if (status != 0)
 252                 goto out;
 253         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 254         nfs41_setup_state_renewal(clp);
 255         nfs_mark_client_ready(clp, NFS_CS_READY);
 256 out:
 257         return status;
 258 }
 259
 260 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 261 {
 262         struct rpc_cred *cred;
 263
 264         spin_lock(&clp->cl_lock);
 265         cred = nfs4_get_machine_cred_locked(clp);
 266         spin_unlock(&clp->cl_lock);
 267         return cred;
 268 }
 269
 270 #endif /* CONFIG_NFS_V4_1 */
 271
 272 static struct rpc_cred *
 273 nfs4_get_setclientid_cred_server(struct nfs_server *server)
 274 {
 275         struct nfs_client *clp = server->nfs_client;
 276         struct rpc_cred *cred = NULL;
 277         struct nfs4_state_owner *sp;
 278         struct rb_node *pos;
 279
 280         spin_lock(&clp->cl_lock);
 281         pos = rb_first(&server->state_owners);
 282         if (pos != NULL) {
 283                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 284                 cred = get_rpccred(sp->so_cred);
 285         }
 286         spin_unlock(&clp->cl_lock);
 287         return cred;
 288 }
 289
 290 /**
 291  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
 292  * @clp: client state handle
 293  *
 294  * Returns an rpc_cred with reference count bumped, or NULL.
 295  */
 296 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 297 {
 298         struct nfs_server *server;
 299         struct rpc_cred *cred;
 300
 301         spin_lock(&clp->cl_lock);
 302         cred = nfs4_get_machine_cred_locked(clp);
 303         spin_unlock(&clp->cl_lock);
 304         if (cred != NULL)
 305                 goto out;
 306
 307         rcu_read_lock();
 308         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 309                 cred = nfs4_get_setclientid_cred_server(server);
 310                 if (cred != NULL)
 311                         break;
 312         }
 313         rcu_read_unlock();
 314
 315 out:
 316         return cred;
 317 }
 318
 319 static void nfs_alloc_unique_id_locked(struct rb_root *root,
 320                                        struct nfs_unique_id *new,
 321                                        __u64 minval, int maxbits)
 322 {
 323         struct rb_node **p, *parent;
 324         struct nfs_unique_id *pos;
 325         __u64 mask = ~0ULL;
 326
 327         if (maxbits < 64)
 328                 mask = (1ULL << maxbits) - 1ULL;
 329
 330         /* Ensure distribution is more or less flat */
 331         get_random_bytes(&new->id, sizeof(new->id));
 332         new->id &= mask;
 333         if (new->id < minval)
 334                 new->id += minval;
 335 retry:
 336         p = &root->rb_node;
 337         parent = NULL;
 338
 339         while (*p != NULL) {
 340                 parent = *p;
 341                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 342
 343                 if (new->id < pos->id)
 344                         p = &(*p)->rb_left;
 345                 else if (new->id > pos->id)
 346                         p = &(*p)->rb_right;
 347                 else
 348                         goto id_exists;
 349         }
 350         rb_link_node(&new->rb_node, parent, p);
 351         rb_insert_color(&new->rb_node, root);
 352         return;
 353 id_exists:
 354         for (;;) {
 355                 new->id++;
 356                 if (new->id < minval || (new->id & mask) != new->id) {
 357                         new->id = minval;
 358                         break;
 359                 }
 360                 parent = rb_next(parent);
 361                 if (parent == NULL)
 362                         break;
 363                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
 364                 if (new->id < pos->id)
 365                         break;
 366         }
 367         goto retry;
 368 }
 369
 370 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
 371 {
 372         rb_erase(&id->rb_node, root);
 373 }
 374
 375 static struct nfs4_state_owner *
 376 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
 377 {
 378         struct rb_node **p = &server->state_owners.rb_node,
 379                        *parent = NULL;
 380         struct nfs4_state_owner *sp, *res = NULL;
 381
 382         while (*p != NULL) {
 383                 parent = *p;
 384                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 385
 386                 if (server < sp->so_server) {
 387                         p = &parent->rb_left;
 388                         continue;
 389                 }
 390                 if (server > sp->so_server) {
 391                         p = &parent->rb_right;
 392                         continue;
 393                 }
 394                 if (cred < sp->so_cred)
 395                         p = &parent->rb_left;
 396                 else if (cred > sp->so_cred)
 397                         p = &parent->rb_right;
 398                 else {
 399                         atomic_inc(&sp->so_count);
 400                         res = sp;
 401                         break;
 402                 }
 403         }
 404         return res;
 405 }
 406
 407 static struct nfs4_state_owner *
 408 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 409 {
 410         struct nfs_server *server = new->so_server;
 411         struct rb_node **p = &server->state_owners.rb_node,
 412                        *parent = NULL;
 413         struct nfs4_state_owner *sp;
 414
 415         while (*p != NULL) {
 416                 parent = *p;
 417                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 418
 419                 if (new->so_cred < sp->so_cred)
 420                         p = &parent->rb_left;
 421                 else if (new->so_cred > sp->so_cred)
 422                         p = &parent->rb_right;
 423                 else {
 424                         atomic_inc(&sp->so_count);
 425                         return sp;
 426                 }
 427         }
 428         nfs_alloc_unique_id_locked(&server->openowner_id,
 429                                         &new->so_owner_id, 1, 64);
 430         rb_link_node(&new->so_server_node, parent, p);
 431         rb_insert_color(&new->so_server_node, &server->state_owners);
 432         return new;
 433 }
 434
 435 static void
 436 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 437 {
 438         struct nfs_server *server = sp->so_server;
 439
 440         if (!RB_EMPTY_NODE(&sp->so_server_node))
 441                 rb_erase(&sp->so_server_node, &server->state_owners);
 442         nfs_free_unique_id(&server->openowner_id, &sp->so_owner_id);
 443 }
 444
 445 /*
 446  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 447  * create a new state_owner.
 448  *
 449  */
 450 static struct nfs4_state_owner *
 451 nfs4_alloc_state_owner(void)
 452 {
 453         struct nfs4_state_owner *sp;
 454
 455         sp = kzalloc(sizeof(*sp),GFP_NOFS);
 456         if (!sp)
 457                 return NULL;
 458         spin_lock_init(&sp->so_lock);
 459         INIT_LIST_HEAD(&sp->so_states);
 460         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
 461         sp->so_seqid.sequence = &sp->so_sequence;
 462         spin_lock_init(&sp->so_sequence.lock);
 463         INIT_LIST_HEAD(&sp->so_sequence.list);
 464         atomic_set(&sp->so_count, 1);
 465         return sp;
 466 }
 467
 468 static void
 469 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 470 {
 471         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
 472                 struct nfs_server *server = sp->so_server;
 473                 struct nfs_client *clp = server->nfs_client;
 474
 475                 spin_lock(&clp->cl_lock);
 476                 rb_erase(&sp->so_server_node, &server->state_owners);
 477                 RB_CLEAR_NODE(&sp->so_server_node);
 478                 spin_unlock(&clp->cl_lock);
 479         }
 480 }
 481
 482 /**
 483  * nfs4_get_state_owner - Look up a state owner given a credential
 484  * @server: nfs_server to search
 485  * @cred: RPC credential to match
 486  *
 487  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 488  */
 489 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 490                                               struct rpc_cred *cred)
 491 {
 492         struct nfs_client *clp = server->nfs_client;
 493         struct nfs4_state_owner *sp, *new;
 494
 495         spin_lock(&clp->cl_lock);
 496         sp = nfs4_find_state_owner_locked(server, cred);
 497         spin_unlock(&clp->cl_lock);
 498         if (sp != NULL)
 499                 return sp;
 500         new = nfs4_alloc_state_owner();
 501         if (new == NULL)
 502                 return NULL;
 503         new->so_server = server;
 504         new->so_cred = cred;
 505         spin_lock(&clp->cl_lock);
 506         sp = nfs4_insert_state_owner_locked(new);
 507         spin_unlock(&clp->cl_lock);
 508         if (sp == new)
 509                 get_rpccred(cred);
 510         else {
 511                 rpc_destroy_wait_queue(&new->so_sequence.wait);
 512                 kfree(new);
 513         }
 514         return sp;
 515 }
 516
 517 /**
 518  * nfs4_put_state_owner - Release a nfs4_state_owner
 519  * @sp: state owner data to release
 520  *
 521  */
 522 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 523 {
 524         struct nfs_client *clp = sp->so_server->nfs_client;
 525         struct rpc_cred *cred = sp->so_cred;
 526
 527         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 528                 return;
 529         nfs4_remove_state_owner_locked(sp);
 530         spin_unlock(&clp->cl_lock);
 531         rpc_destroy_wait_queue(&sp->so_sequence.wait);
 532         put_rpccred(cred);
 533         kfree(sp);
 534 }
 535
 536 static struct nfs4_state *
 537 nfs4_alloc_open_state(void)
 538 {
 539         struct nfs4_state *state;
 540
 541         state = kzalloc(sizeof(*state), GFP_NOFS);
 542         if (!state)
 543                 return NULL;
 544         atomic_set(&state->count, 1);
 545         INIT_LIST_HEAD(&state->lock_states);
 546         spin_lock_init(&state->state_lock);
 547         seqlock_init(&state->seqlock);
 548         return state;
 549 }
 550
 551 void
 552 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 553 {
 554         if (state->state == fmode)
 555                 return;
 556         /* NB! List reordering - see the reclaim code for why.  */
 557         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 558                 if (fmode & FMODE_WRITE)
 559                         list_move(&state->open_states, &state->owner->so_states);
 560                 else
 561                         list_move_tail(&state->open_states, &state->owner->so_states);
 562         }
 563         state->state = fmode;
 564 }
 565
 566 static struct nfs4_state *
 567 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 568 {
 569         struct nfs_inode *nfsi = NFS_I(inode);
 570         struct nfs4_state *state;
 571
 572         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 573                 if (state->owner != owner)
 574                         continue;
 575                 if (atomic_inc_not_zero(&state->count))
 576                         return state;
 577         }
 578         return NULL;
 579 }
 580
 581 static void
 582 nfs4_free_open_state(struct nfs4_state *state)
 583 {
 584         kfree(state);
 585 }
 586
 587 struct nfs4_state *
 588 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 589 {
 590         struct nfs4_state *state, *new;
 591         struct nfs_inode *nfsi = NFS_I(inode);
 592
 593         spin_lock(&inode->i_lock);
 594         state = __nfs4_find_state_byowner(inode, owner);
 595         spin_unlock(&inode->i_lock);
 596         if (state)
 597                 goto out;
 598         new = nfs4_alloc_open_state();
 599         spin_lock(&owner->so_lock);
 600         spin_lock(&inode->i_lock);
 601         state = __nfs4_find_state_byowner(inode, owner);
 602         if (state == NULL && new != NULL) {
 603                 state = new;
 604                 state->owner = owner;
 605                 atomic_inc(&owner->so_count);
 606                 list_add(&state->inode_states, &nfsi->open_states);
 607                 ihold(inode);
 608                 state->inode = inode;
 609                 spin_unlock(&inode->i_lock);
 610                 /* Note: The reclaim code dictates that we add stateless
 611                  * and read-only stateids to the end of the list */
 612                 list_add_tail(&state->open_states, &owner->so_states);
 613                 spin_unlock(&owner->so_lock);
 614         } else {
 615                 spin_unlock(&inode->i_lock);
 616                 spin_unlock(&owner->so_lock);
 617                 if (new)
 618                         nfs4_free_open_state(new);
 619         }
 620 out:
 621         return state;
 622 }
 623
 624 void nfs4_put_open_state(struct nfs4_state *state)
 625 {
 626         struct inode *inode = state->inode;
 627         struct nfs4_state_owner *owner = state->owner;
 628
 629         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 630                 return;
 631         spin_lock(&inode->i_lock);
 632         list_del(&state->inode_states);
 633         list_del(&state->open_states);
 634         spin_unlock(&inode->i_lock);
 635         spin_unlock(&owner->so_lock);
 636         iput(inode);
 637         nfs4_free_open_state(state);
 638         nfs4_put_state_owner(owner);
 639 }
 640
 641 /*
 642  * Close the current file.
 643  */
 644 static void __nfs4_close(struct path *path, struct nfs4_state *state,
 645                 fmode_t fmode, gfp_t gfp_mask, int wait)
 646 {
 647         struct nfs4_state_owner *owner = state->owner;
 648         int call_close = 0;
 649         fmode_t newstate;
 650
 651         atomic_inc(&owner->so_count);
 652         /* Protect against nfs4_find_state() */
 653         spin_lock(&owner->so_lock);
 654         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 655                 case FMODE_READ:
 656                         state->n_rdonly--;
 657                         break;
 658                 case FMODE_WRITE:
 659                         state->n_wronly--;
 660                         break;
 661                 case FMODE_READ|FMODE_WRITE:
 662                         state->n_rdwr--;
 663         }
 664         newstate = FMODE_READ|FMODE_WRITE;
 665         if (state->n_rdwr == 0) {
 666                 if (state->n_rdonly == 0) {
 667                         newstate &= ~FMODE_READ;
 668                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 669                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 670                 }
 671                 if (state->n_wronly == 0) {
 672                         newstate &= ~FMODE_WRITE;
 673                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 674                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 675                 }
 676                 if (newstate == 0)
 677                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 678         }
 679         nfs4_state_set_mode_locked(state, newstate);
 680         spin_unlock(&owner->so_lock);
 681
 682         if (!call_close) {
 683                 nfs4_put_open_state(state);
 684                 nfs4_put_state_owner(owner);
 685         } else {
 686                 bool roc = pnfs_roc(state->inode);
 687
 688                 nfs4_do_close(path, state, gfp_mask, wait, roc);
 689         }
 690 }
 691
 692 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
 693 {
 694         __nfs4_close(path, state, fmode, GFP_NOFS, 0);
 695 }
 696
 697 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
 698 {
 699         __nfs4_close(path, state, fmode, GFP_KERNEL, 1);
 700 }
 701
 702 /*
 703  * Search the state->lock_states for an existing lock_owner
 704  * that is compatible with current->files
 705  */
 706 static struct nfs4_lock_state *
 707 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 708 {
 709         struct nfs4_lock_state *pos;
 710         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 711                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
 712                         continue;
 713                 switch (pos->ls_owner.lo_type) {
 714                 case NFS4_POSIX_LOCK_TYPE:
 715                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
 716                                 continue;
 717                         break;
 718                 case NFS4_FLOCK_LOCK_TYPE:
 719                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
 720                                 continue;
 721                 }
 722                 atomic_inc(&pos->ls_count);
 723                 return pos;
 724         }
 725         return NULL;
 726 }
 727
 728 /*
 729  * Return a compatible lock_state. If no initialized lock_state structure
 730  * exists, return an uninitialized one.
 731  *
 732  */
 733 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 734 {
 735         struct nfs4_lock_state *lsp;
 736         struct nfs_server *server = state->owner->so_server;
 737         struct nfs_client *clp = server->nfs_client;
 738
 739         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 740         if (lsp == NULL)
 741                 return NULL;
 742         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
 743         spin_lock_init(&lsp->ls_sequence.lock);
 744         INIT_LIST_HEAD(&lsp->ls_sequence.list);
 745         lsp->ls_seqid.sequence = &lsp->ls_sequence;
 746         atomic_set(&lsp->ls_count, 1);
 747         lsp->ls_state = state;
 748         lsp->ls_owner.lo_type = type;
 749         switch (lsp->ls_owner.lo_type) {
 750         case NFS4_FLOCK_LOCK_TYPE:
 751                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
 752                 break;
 753         case NFS4_POSIX_LOCK_TYPE:
 754                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
 755                 break;
 756         default:
 757                 kfree(lsp);
 758                 return NULL;
 759         }
 760         spin_lock(&clp->cl_lock);
 761         nfs_alloc_unique_id_locked(&server->lockowner_id, &lsp->ls_id, 1, 64);
 762         spin_unlock(&clp->cl_lock);
 763         INIT_LIST_HEAD(&lsp->ls_locks);
 764         return lsp;
 765 }
 766
 767 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
 768 {
 769         struct nfs_server *server = lsp->ls_state->owner->so_server;
 770         struct nfs_client *clp = server->nfs_client;
 771
 772         spin_lock(&clp->cl_lock);
 773         nfs_free_unique_id(&server->lockowner_id, &lsp->ls_id);
 774         spin_unlock(&clp->cl_lock);
 775         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
 776         kfree(lsp);
 777 }
 778
 779 /*
 780  * Return a compatible lock_state. If no initialized lock_state structure
 781  * exists, return an uninitialized one.
 782  *
 783  */
 784 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
 785 {
 786         struct nfs4_lock_state *lsp, *new = NULL;
 787
 788         for(;;) {
 789                 spin_lock(&state->state_lock);
 790                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
 791                 if (lsp != NULL)
 792                         break;
 793                 if (new != NULL) {
 794                         list_add(&new->ls_locks, &state->lock_states);
 795                         set_bit(LK_STATE_IN_USE, &state->flags);
 796                         lsp = new;
 797                         new = NULL;
 798                         break;
 799                 }
 800                 spin_unlock(&state->state_lock);
 801                 new = nfs4_alloc_lock_state(state, owner, pid, type);
 802                 if (new == NULL)
 803                         return NULL;
 804         }
 805         spin_unlock(&state->state_lock);
 806         if (new != NULL)
 807                 nfs4_free_lock_state(new);
 808         return lsp;
 809 }
 810
 811 /*
 812  * Release reference to lock_state, and free it if we see that
 813  * it is no longer in use
 814  */
 815 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 816 {
 817         struct nfs4_state *state;
 818
 819         if (lsp == NULL)
 820                 return;
 821         state = lsp->ls_state;
 822         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 823                 return;
 824         list_del(&lsp->ls_locks);
 825         if (list_empty(&state->lock_states))
 826                 clear_bit(LK_STATE_IN_USE, &state->flags);
 827         spin_unlock(&state->state_lock);
 828         if (lsp->ls_flags & NFS_LOCK_INITIALIZED)
 829                 nfs4_release_lockowner(lsp);
 830         nfs4_free_lock_state(lsp);
 831 }
 832
 833 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 834 {
 835         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 836
 837         dst->fl_u.nfs4_fl.owner = lsp;
 838         atomic_inc(&lsp->ls_count);
 839 }
 840
 841 static void nfs4_fl_release_lock(struct file_lock *fl)
 842 {
 843         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 844 }
 845
 846 static const struct file_lock_operations nfs4_fl_lock_ops = {
 847         .fl_copy_lock = nfs4_fl_copy_lock,
 848         .fl_release_private = nfs4_fl_release_lock,
 849 };
 850
 851 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 852 {
 853         struct nfs4_lock_state *lsp;
 854
 855         if (fl->fl_ops != NULL)
 856                 return 0;
 857         if (fl->fl_flags & FL_POSIX)
 858                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
 859         else if (fl->fl_flags & FL_FLOCK)
 860                 lsp = nfs4_get_lock_state(state, 0, fl->fl_pid, NFS4_FLOCK_LOCK_TYPE);
 861         else
 862                 return -EINVAL;
 863         if (lsp == NULL)
 864                 return -ENOMEM;
 865         fl->fl_u.nfs4_fl.owner = lsp;
 866         fl->fl_ops = &nfs4_fl_lock_ops;
 867         return 0;
 868 }
 869
 870 /*
 871  * Byte-range lock aware utility to initialize the stateid of read/write
 872  * requests.
 873  */
 874 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid)
 875 {
 876         struct nfs4_lock_state *lsp;
 877         int seq;
 878
 879         do {
 880                 seq = read_seqbegin(&state->seqlock);
 881                 memcpy(dst, &state->stateid, sizeof(*dst));
 882         } while (read_seqretry(&state->seqlock, seq));
 883         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 884                 return;
 885
 886         spin_lock(&state->state_lock);
 887         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
 888         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
 889                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 890         spin_unlock(&state->state_lock);
 891         nfs4_put_lock_state(lsp);
 892 }
 893
 894 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
 895 {
 896         struct nfs_seqid *new;
 897
 898         new = kmalloc(sizeof(*new), gfp_mask);
 899         if (new != NULL) {
 900                 new->sequence = counter;
 901                 INIT_LIST_HEAD(&new->list);
 902         }
 903         return new;
 904 }
 905
 906 void nfs_release_seqid(struct nfs_seqid *seqid)
 907 {
 908         if (!list_empty(&seqid->list)) {
 909                 struct rpc_sequence *sequence = seqid->sequence->sequence;
 910
 911                 spin_lock(&sequence->lock);
 912                 list_del_init(&seqid->list);
 913                 spin_unlock(&sequence->lock);
 914                 rpc_wake_up(&sequence->wait);
 915         }
 916 }
 917
 918 void nfs_free_seqid(struct nfs_seqid *seqid)
 919 {
 920         nfs_release_seqid(seqid);
 921         kfree(seqid);
 922 }
 923
 924 /*
 925  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 926  * failed with a seqid incrementing error -
 927  * see comments nfs_fs.h:seqid_mutating_error()
 928  */
 929 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 930 {
 931         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
 932         switch (status) {
 933                 case 0:
 934                         break;
 935                 case -NFS4ERR_BAD_SEQID:
 936                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
 937                                 return;
 938                         printk(KERN_WARNING "NFS: v4 server returned a bad"
 939                                         " sequence-id error on an"
 940                                         " unconfirmed sequence %p!\n",
 941                                         seqid->sequence);
 942                 case -NFS4ERR_STALE_CLIENTID:
 943                 case -NFS4ERR_STALE_STATEID:
 944                 case -NFS4ERR_BAD_STATEID:
 945                 case -NFS4ERR_BADXDR:
 946                 case -NFS4ERR_RESOURCE:
 947                 case -NFS4ERR_NOFILEHANDLE:
 948                         /* Non-seqid mutating errors */
 949                         return;
 950         };
 951         /*
 952          * Note: no locking needed as we are guaranteed to be first
 953          * on the sequence list
 954          */
 955         seqid->sequence->counter++;
 956 }
 957
 958 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
 959 {
 960         struct nfs4_state_owner *sp = container_of(seqid->sequence,
 961                                         struct nfs4_state_owner, so_seqid);
 962         struct nfs_server *server = sp->so_server;
 963
 964         if (status == -NFS4ERR_BAD_SEQID)
 965                 nfs4_drop_state_owner(sp);
 966         if (!nfs4_has_session(server->nfs_client))
 967                 nfs_increment_seqid(status, seqid);
 968 }
 969
 970 /*
 971  * Increment the seqid if the LOCK/LOCKU succeeded, or
 972  * failed with a seqid incrementing error -
 973  * see comments nfs_fs.h:seqid_mutating_error()
 974  */
 975 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
 976 {
 977         nfs_increment_seqid(status, seqid);
 978 }
 979
 980 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
 981 {
 982         struct rpc_sequence *sequence = seqid->sequence->sequence;
 983         int status = 0;
 984
 985         spin_lock(&sequence->lock);
 986         if (list_empty(&seqid->list))
 987                 list_add_tail(&seqid->list, &sequence->list);
 988         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
 989                 goto unlock;
 990         rpc_sleep_on(&sequence->wait, task, NULL);
 991         status = -EAGAIN;
 992 unlock:
 993         spin_unlock(&sequence->lock);
 994         return status;
 995 }
 996
 997 static int nfs4_run_state_manager(void *);
 998
 999 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1000 {
1001         smp_mb__before_clear_bit();
1002         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1003         smp_mb__after_clear_bit();
1004         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1005         rpc_wake_up(&clp->cl_rpcwaitq);
1006 }
1007
1008 /*
1009  * Schedule the nfs_client asynchronous state management routine
1010  */
1011 void nfs4_schedule_state_manager(struct nfs_client *clp)
1012 {
1013         struct task_struct *task;
1014
1015         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1016                 return;
1017         __module_get(THIS_MODULE);
1018         atomic_inc(&clp->cl_count);
1019         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
1020                                 rpc_peeraddr2str(clp->cl_rpcclient,
1021                                                         RPC_DISPLAY_ADDR));
1022         if (!IS_ERR(task))
1023                 return;
1024         nfs4_clear_state_manager_bit(clp);
1025         nfs_put_client(clp);
1026         module_put(THIS_MODULE);
1027 }
1028
1029 /*
1030  * Schedule a lease recovery attempt
1031  */
1032 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1033 {
1034         if (!clp)
1035                 return;
1036         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1037                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1038         nfs4_schedule_state_manager(clp);
1039 }
1040
1041 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1042 {
1043
1044         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1045         /* Don't recover state that expired before the reboot */
1046         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1047                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1048                 return 0;
1049         }
1050         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1051         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1052         return 1;
1053 }
1054
1055 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1056 {
1057         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1058         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1059         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1060         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1061         return 1;
1062 }
1063
1064 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1065 {
1066         struct nfs_client *clp = server->nfs_client;
1067
1068         nfs4_state_mark_reclaim_nograce(clp, state);
1069         nfs4_schedule_state_manager(clp);
1070 }
1071
1072 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1073 {
1074         struct inode *inode = state->inode;
1075         struct nfs_inode *nfsi = NFS_I(inode);
1076         struct file_lock *fl;
1077         int status = 0;
1078
1079         if (inode->i_flock == NULL)
1080                 return 0;
1081
1082         /* Guard against delegation returns and new lock/unlock calls */
1083         down_write(&nfsi->rwsem);
1084         /* Protect inode->i_flock using the BKL */
1085         lock_flocks();
1086         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1087                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1088                         continue;
1089                 if (nfs_file_open_context(fl->fl_file)->state != state)
1090                         continue;
1091                 unlock_flocks();
1092                 status = ops->recover_lock(state, fl);
1093                 switch (status) {
1094                         case 0:
1095                                 break;
1096                         case -ESTALE:
1097                         case -NFS4ERR_ADMIN_REVOKED:
1098                         case -NFS4ERR_STALE_STATEID:
1099                         case -NFS4ERR_BAD_STATEID:
1100                         case -NFS4ERR_EXPIRED:
1101                         case -NFS4ERR_NO_GRACE:
1102                         case -NFS4ERR_STALE_CLIENTID:
1103                         case -NFS4ERR_BADSESSION:
1104                         case -NFS4ERR_BADSLOT:
1105                         case -NFS4ERR_BAD_HIGH_SLOT:
1106                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1107                                 goto out;
1108                         default:
1109                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1110                                                 __func__, status);
1111                         case -ENOMEM:
1112                         case -NFS4ERR_DENIED:
1113                         case -NFS4ERR_RECLAIM_BAD:
1114                         case -NFS4ERR_RECLAIM_CONFLICT:
1115                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1116                                 status = 0;
1117                 }
1118                 lock_flocks();
1119         }
1120         unlock_flocks();
1121 out:
1122         up_write(&nfsi->rwsem);
1123         return status;
1124 }
1125
1126 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1127 {
1128         struct nfs4_state *state;
1129         struct nfs4_lock_state *lock;
1130         int status = 0;
1131
1132         /* Note: we rely on the sp->so_states list being ordered
1133          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1134          * states first.
1135          * This is needed to ensure that the server won't give us any
1136          * read delegations that we have to return if, say, we are
1137          * recovering after a network partition or a reboot from a
1138          * server that doesn't support a grace period.
1139          */
1140 restart:
1141         spin_lock(&sp->so_lock);
1142         list_for_each_entry(state, &sp->so_states, open_states) {
1143                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1144                         continue;
1145                 if (state->state == 0)
1146                         continue;
1147                 atomic_inc(&state->count);
1148                 spin_unlock(&sp->so_lock);
1149                 status = ops->recover_open(sp, state);
1150                 if (status >= 0) {
1151                         status = nfs4_reclaim_locks(state, ops);
1152                         if (status >= 0) {
1153                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1154                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1155                                                 printk("%s: Lock reclaim failed!\n",
1156                                                         __func__);
1157                                 }
1158                                 nfs4_put_open_state(state);
1159                                 goto restart;
1160                         }
1161                 }
1162                 switch (status) {
1163                         default:
1164                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
1165                                                 __func__, status);
1166                         case -ENOENT:
1167                         case -ENOMEM:
1168                         case -ESTALE:
1169                                 /*
1170                                  * Open state on this file cannot be recovered
1171                                  * All we can do is revert to using the zero stateid.
1172                                  */
1173                                 memset(state->stateid.data, 0,
1174                                         sizeof(state->stateid.data));
1175                                 /* Mark the file as being 'closed' */
1176                                 state->state = 0;
1177                                 break;
1178                         case -EKEYEXPIRED:
1179                                 /*
1180                                  * User RPCSEC_GSS context has expired.
1181                                  * We cannot recover this stateid now, so
1182                                  * skip it and allow recovery thread to
1183                                  * proceed.
1184                                  */
1185                                 break;
1186                         case -NFS4ERR_ADMIN_REVOKED:
1187                         case -NFS4ERR_STALE_STATEID:
1188                         case -NFS4ERR_BAD_STATEID:
1189                         case -NFS4ERR_RECLAIM_BAD:
1190                         case -NFS4ERR_RECLAIM_CONFLICT:
1191                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1192                                 break;
1193                         case -NFS4ERR_EXPIRED:
1194                         case -NFS4ERR_NO_GRACE:
1195                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1196                         case -NFS4ERR_STALE_CLIENTID:
1197                         case -NFS4ERR_BADSESSION:
1198                         case -NFS4ERR_BADSLOT:
1199                         case -NFS4ERR_BAD_HIGH_SLOT:
1200                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1201                                 goto out_err;
1202                 }
1203                 nfs4_put_open_state(state);
1204                 goto restart;
1205         }
1206         spin_unlock(&sp->so_lock);
1207         return 0;
1208 out_err:
1209         nfs4_put_open_state(state);
1210         return status;
1211 }
1212
1213 static void nfs4_clear_open_state(struct nfs4_state *state)
1214 {
1215         struct nfs4_lock_state *lock;
1216
1217         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1218         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1219         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1220         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1221         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1222                 lock->ls_seqid.flags = 0;
1223                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1224         }
1225 }
1226
1227 static void nfs4_reset_seqids(struct nfs_server *server,
1228         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1229 {
1230         struct nfs_client *clp = server->nfs_client;
1231         struct nfs4_state_owner *sp;
1232         struct rb_node *pos;
1233         struct nfs4_state *state;
1234
1235         spin_lock(&clp->cl_lock);
1236         for (pos = rb_first(&server->state_owners);
1237              pos != NULL;
1238              pos = rb_next(pos)) {
1239                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1240                 sp->so_seqid.flags = 0;
1241                 spin_lock(&sp->so_lock);
1242                 list_for_each_entry(state, &sp->so_states, open_states) {
1243                         if (mark_reclaim(clp, state))
1244                                 nfs4_clear_open_state(state);
1245                 }
1246                 spin_unlock(&sp->so_lock);
1247         }
1248         spin_unlock(&clp->cl_lock);
1249 }
1250
1251 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1252         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1253 {
1254         struct nfs_server *server;
1255
1256         rcu_read_lock();
1257         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1258                 nfs4_reset_seqids(server, mark_reclaim);
1259         rcu_read_unlock();
1260 }
1261
1262 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1263 {
1264         /* Mark all delegations for reclaim */
1265         nfs_delegation_mark_reclaim(clp);
1266         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1267 }
1268
1269 static void nfs4_reclaim_complete(struct nfs_client *clp,
1270                                  const struct nfs4_state_recovery_ops *ops)
1271 {
1272         /* Notify the server we're done reclaiming our state */
1273         if (ops->reclaim_complete)
1274                 (void)ops->reclaim_complete(clp);
1275 }
1276
1277 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1278 {
1279         struct nfs_client *clp = server->nfs_client;
1280         struct nfs4_state_owner *sp;
1281         struct rb_node *pos;
1282         struct nfs4_state *state;
1283
1284         spin_lock(&clp->cl_lock);
1285         for (pos = rb_first(&server->state_owners);
1286              pos != NULL;
1287              pos = rb_next(pos)) {
1288                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1289                 spin_lock(&sp->so_lock);
1290                 list_for_each_entry(state, &sp->so_states, open_states) {
1291                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1292                                                 &state->flags))
1293                                 continue;
1294                         nfs4_state_mark_reclaim_nograce(clp, state);
1295                 }
1296                 spin_unlock(&sp->so_lock);
1297         }
1298         spin_unlock(&clp->cl_lock);
1299 }
1300
1301 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1302 {
1303         struct nfs_server *server;
1304
1305         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1306                 return 0;
1307
1308         rcu_read_lock();
1309         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1310                 nfs4_clear_reclaim_server(server);
1311         rcu_read_unlock();
1312
1313         nfs_delegation_reap_unclaimed(clp);
1314         return 1;
1315 }
1316
1317 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1318 {
1319         if (!nfs4_state_clear_reclaim_reboot(clp))
1320                 return;
1321         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1322 }
1323
1324 static void nfs_delegation_clear_all(struct nfs_client *clp)
1325 {
1326         nfs_delegation_mark_reclaim(clp);
1327         nfs_delegation_reap_unclaimed(clp);
1328 }
1329
1330 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1331 {
1332         nfs_delegation_clear_all(clp);
1333         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1334 }
1335
1336 static void nfs4_warn_keyexpired(const char *s)
1337 {
1338         printk_ratelimited(KERN_WARNING "Error: state manager"
1339                         " encountered RPCSEC_GSS session"
1340                         " expired against NFSv4 server %s.\n",
1341                         s);
1342 }
1343
1344 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1345 {
1346         switch (error) {
1347                 case -NFS4ERR_CB_PATH_DOWN:
1348                         nfs_handle_cb_pathdown(clp);
1349                         return 0;
1350                 case -NFS4ERR_NO_GRACE:
1351                         nfs4_state_end_reclaim_reboot(clp);
1352                         return 0;
1353                 case -NFS4ERR_STALE_CLIENTID:
1354                 case -NFS4ERR_LEASE_MOVED:
1355                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1356                         nfs4_state_clear_reclaim_reboot(clp);
1357                         nfs4_state_start_reclaim_reboot(clp);
1358                         break;
1359                 case -NFS4ERR_EXPIRED:
1360                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1361                         nfs4_state_start_reclaim_nograce(clp);
1362                         break;
1363                 case -NFS4ERR_BADSESSION:
1364                 case -NFS4ERR_BADSLOT:
1365                 case -NFS4ERR_BAD_HIGH_SLOT:
1366                 case -NFS4ERR_DEADSESSION:
1367                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1368                 case -NFS4ERR_SEQ_FALSE_RETRY:
1369                 case -NFS4ERR_SEQ_MISORDERED:
1370                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1371                         /* Zero session reset errors */
1372                         return 0;
1373                 case -EKEYEXPIRED:
1374                         /* Nothing we can do */
1375                         nfs4_warn_keyexpired(clp->cl_hostname);
1376                         return 0;
1377         }
1378         return error;
1379 }
1380
1381 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1382 {
1383         struct nfs4_state_owner *sp;
1384         struct nfs_server *server;
1385         struct rb_node *pos;
1386         int status = 0;
1387
1388 restart:
1389         rcu_read_lock();
1390         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1391                 spin_lock(&clp->cl_lock);
1392                 for (pos = rb_first(&server->state_owners);
1393                      pos != NULL;
1394                      pos = rb_next(pos)) {
1395                         sp = rb_entry(pos,
1396                                 struct nfs4_state_owner, so_server_node);
1397                         if (!test_and_clear_bit(ops->owner_flag_bit,
1398                                                         &sp->so_flags))
1399                                 continue;
1400                         atomic_inc(&sp->so_count);
1401                         spin_unlock(&clp->cl_lock);
1402                         rcu_read_unlock();
1403
1404                         status = nfs4_reclaim_open_state(sp, ops);
1405                         if (status < 0) {
1406                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1407                                 nfs4_put_state_owner(sp);
1408                                 return nfs4_recovery_handle_error(clp, status);
1409                         }
1410
1411                         nfs4_put_state_owner(sp);
1412                         goto restart;
1413                 }
1414                 spin_unlock(&clp->cl_lock);
1415         }
1416         rcu_read_unlock();
1417         return status;
1418 }
1419
1420 static int nfs4_check_lease(struct nfs_client *clp)
1421 {
1422         struct rpc_cred *cred;
1423         const struct nfs4_state_maintenance_ops *ops =
1424                 clp->cl_mvops->state_renewal_ops;
1425         int status = -NFS4ERR_EXPIRED;
1426
1427         /* Is the client already known to have an expired lease? */
1428         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1429                 return 0;
1430         spin_lock(&clp->cl_lock);
1431         cred = ops->get_state_renewal_cred_locked(clp);
1432         spin_unlock(&clp->cl_lock);
1433         if (cred == NULL) {
1434                 cred = nfs4_get_setclientid_cred(clp);
1435                 if (cred == NULL)
1436                         goto out;
1437         }
1438         status = ops->renew_lease(clp, cred);
1439         put_rpccred(cred);
1440 out:
1441         return nfs4_recovery_handle_error(clp, status);
1442 }
1443
1444 static int nfs4_reclaim_lease(struct nfs_client *clp)
1445 {
1446         struct rpc_cred *cred;
1447         const struct nfs4_state_recovery_ops *ops =
1448                 clp->cl_mvops->reboot_recovery_ops;
1449         int status = -ENOENT;
1450
1451         cred = ops->get_clid_cred(clp);
1452         if (cred != NULL) {
1453                 status = ops->establish_clid(clp, cred);
1454                 put_rpccred(cred);
1455                 /* Handle case where the user hasn't set up machine creds */
1456                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1457                         nfs4_clear_machine_cred(clp);
1458                         status = -EAGAIN;
1459                 }
1460                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1461                         status = -EPROTONOSUPPORT;
1462         }
1463         return status;
1464 }
1465
1466 #ifdef CONFIG_NFS_V4_1
1467 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1468 {
1469         nfs4_schedule_lease_recovery(session->clp);
1470 }
1471 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1472
1473 void nfs41_handle_recall_slot(struct nfs_client *clp)
1474 {
1475         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1476         nfs4_schedule_state_manager(clp);
1477 }
1478
1479 static void nfs4_reset_all_state(struct nfs_client *clp)
1480 {
1481         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1482                 clp->cl_boot_time = CURRENT_TIME;
1483                 nfs4_state_start_reclaim_nograce(clp);
1484                 nfs4_schedule_state_manager(clp);
1485         }
1486 }
1487
1488 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1489 {
1490         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1491                 nfs4_state_start_reclaim_reboot(clp);
1492                 nfs4_schedule_state_manager(clp);
1493         }
1494 }
1495
1496 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1497 {
1498         /* Temporary */
1499         nfs4_reset_all_state(clp);
1500 }
1501
1502 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1503 {
1504         /* This will need to handle layouts too */
1505         nfs_expire_all_delegations(clp);
1506 }
1507
1508 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1509 {
1510         nfs_expire_all_delegations(clp);
1511         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1512                 nfs4_schedule_state_manager(clp);
1513 }
1514
1515 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1516 {
1517         if (!flags)
1518                 return;
1519         else if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1520                 nfs41_handle_server_reboot(clp);
1521         else if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1522                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1523                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1524                             SEQ4_STATUS_LEASE_MOVED))
1525                 nfs41_handle_state_revoked(clp);
1526         else if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1527                 nfs41_handle_recallable_state_revoked(clp);
1528         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1529                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1530                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1531                 nfs41_handle_cb_path_down(clp);
1532 }
1533
1534 static int nfs4_reset_session(struct nfs_client *clp)
1535 {
1536         int status;
1537
1538         nfs4_begin_drain_session(clp);
1539         status = nfs4_proc_destroy_session(clp->cl_session);
1540         if (status && status != -NFS4ERR_BADSESSION &&
1541             status != -NFS4ERR_DEADSESSION) {
1542                 status = nfs4_recovery_handle_error(clp, status);
1543                 goto out;
1544         }
1545
1546         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1547         status = nfs4_proc_create_session(clp);
1548         if (status) {
1549                 status = nfs4_recovery_handle_error(clp, status);
1550                 goto out;
1551         }
1552         /* create_session negotiated new slot table */
1553         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1554
1555          /* Let the state manager reestablish state */
1556         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1557                 nfs41_setup_state_renewal(clp);
1558 out:
1559         return status;
1560 }
1561
1562 static int nfs4_recall_slot(struct nfs_client *clp)
1563 {
1564         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1565         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1566         struct nfs4_slot *new, *old;
1567         int i;
1568
1569         nfs4_begin_drain_session(clp);
1570         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1571                       GFP_NOFS);
1572         if (!new)
1573                 return -ENOMEM;
1574
1575         spin_lock(&fc_tbl->slot_tbl_lock);
1576         for (i = 0; i < fc_tbl->target_max_slots; i++)
1577                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1578         old = fc_tbl->slots;
1579         fc_tbl->slots = new;
1580         fc_tbl->max_slots = fc_tbl->target_max_slots;
1581         fc_tbl->target_max_slots = 0;
1582         fc_attrs->max_reqs = fc_tbl->max_slots;
1583         spin_unlock(&fc_tbl->slot_tbl_lock);
1584
1585         kfree(old);
1586         nfs4_end_drain_session(clp);
1587         return 0;
1588 }
1589
1590 #else /* CONFIG_NFS_V4_1 */
1591 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1592 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1593 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1594 #endif /* CONFIG_NFS_V4_1 */
1595
1596 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1597  * on EXCHANGE_ID for v4.1
1598  */
1599 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1600 {
1601         switch (status) {
1602         case -NFS4ERR_CLID_INUSE:
1603         case -NFS4ERR_STALE_CLIENTID:
1604                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1605                 break;
1606         case -NFS4ERR_DELAY:
1607         case -ETIMEDOUT:
1608         case -EAGAIN:
1609                 ssleep(1);
1610                 break;
1611
1612         case -EKEYEXPIRED:
1613                 nfs4_warn_keyexpired(clp->cl_hostname);
1614         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1615                                  * in nfs4_exchange_id */
1616         default:
1617                 return;
1618         }
1619         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1620 }
1621
1622 static void nfs4_state_manager(struct nfs_client *clp)
1623 {
1624         int status = 0;
1625
1626         /* Ensure exclusive access to NFSv4 state */
1627         do {
1628                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1629                         /* We're going to have to re-establish a clientid */
1630                         status = nfs4_reclaim_lease(clp);
1631                         if (status) {
1632                                 nfs4_set_lease_expired(clp, status);
1633                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1634                                                         &clp->cl_state))
1635                                         continue;
1636                                 if (clp->cl_cons_state ==
1637                                                         NFS_CS_SESSION_INITING)
1638                                         nfs_mark_client_ready(clp, status);
1639                                 goto out_error;
1640                         }
1641                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1642                         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1643                         pnfs_destroy_all_layouts(clp);
1644                 }
1645
1646                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1647                         status = nfs4_check_lease(clp);
1648                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1649                                 continue;
1650                         if (status < 0 && status != -NFS4ERR_CB_PATH_DOWN)
1651                                 goto out_error;
1652                 }
1653
1654                 /* Initialize or reset the session */
1655                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1656                    && nfs4_has_session(clp)) {
1657                         status = nfs4_reset_session(clp);
1658                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1659                                 continue;
1660                         if (status < 0)
1661                                 goto out_error;
1662                 }
1663
1664                 /* First recover reboot state... */
1665                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1666                         status = nfs4_do_reclaim(clp,
1667                                 clp->cl_mvops->reboot_recovery_ops);
1668                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1669                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1670                                 continue;
1671                         nfs4_state_end_reclaim_reboot(clp);
1672                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1673                                 continue;
1674                         if (status < 0)
1675                                 goto out_error;
1676                 }
1677
1678                 /* Now recover expired state... */
1679                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1680                         status = nfs4_do_reclaim(clp,
1681                                 clp->cl_mvops->nograce_recovery_ops);
1682                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1683                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1684                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1685                                 continue;
1686                         if (status < 0)
1687                                 goto out_error;
1688                 }
1689
1690                 nfs4_end_drain_session(clp);
1691                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1692                         nfs_client_return_marked_delegations(clp);
1693                         continue;
1694                 }
1695                 /* Recall session slots */
1696                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1697                    && nfs4_has_session(clp)) {
1698                         status = nfs4_recall_slot(clp);
1699                         if (status < 0)
1700                                 goto out_error;
1701                         continue;
1702                 }
1703
1704
1705                 nfs4_clear_state_manager_bit(clp);
1706                 /* Did we race with an attempt to give us more work? */
1707                 if (clp->cl_state == 0)
1708                         break;
1709                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1710                         break;
1711         } while (atomic_read(&clp->cl_count) > 1);
1712         return;
1713 out_error:
1714         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1715                         " with error %d\n", clp->cl_hostname, -status);
1716         nfs4_end_drain_session(clp);
1717         nfs4_clear_state_manager_bit(clp);
1718 }
1719
1720 static int nfs4_run_state_manager(void *ptr)
1721 {
1722         struct nfs_client *clp = ptr;
1723
1724         allow_signal(SIGKILL);
1725         nfs4_state_manager(clp);
1726         nfs_put_client(clp);
1727         module_put_and_exit(0);
1728         return 0;
1729 }
1730
1731 /*
1732  * Local variables:
1733  *  c-basic-offset: 8
1734  * End:
1735  */