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 #include <linux/jiffies.h>
  53
  54 #include <linux/sunrpc/clnt.h>
  55
  56 #include "nfs4_fs.h"
  57 #include "callback.h"
  58 #include "delegation.h"
  59 #include "internal.h"
  60 #include "nfs4session.h"
  61 #include "pnfs.h"
  62 #include "netns.h"
  63
  64 #define NFSDBG_FACILITY         NFSDBG_STATE
  65
  66 #define OPENOWNER_POOL_SIZE     8
  67
  68 const nfs4_stateid zero_stateid;
  69 static DEFINE_MUTEX(nfs_clid_init_mutex);
  70
  71 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  72 {
  73         struct nfs4_setclientid_res clid = {
  74                 .clientid = clp->cl_clientid,
  75                 .confirm = clp->cl_confirm,
  76         };
  77         unsigned short port;
  78         int status;
  79         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  80
  81         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
  82                 goto do_confirm;
  83         port = nn->nfs_callback_tcpport;
  84         if (clp->cl_addr.ss_family == AF_INET6)
  85                 port = nn->nfs_callback_tcpport6;
  86
  87         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
  88         if (status != 0)
  89                 goto out;
  90         clp->cl_clientid = clid.clientid;
  91         clp->cl_confirm = clid.confirm;
  92         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  93 do_confirm:
  94         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
  95         if (status != 0)
  96                 goto out;
  97         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  98         nfs4_schedule_state_renewal(clp);
  99 out:
 100         return status;
 101 }
 102
 103 /**
 104  * nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
 105  *
 106  * @clp: nfs_client under test
 107  * @result: OUT: found nfs_client, or clp
 108  * @cred: credential to use for trunking test
 109  *
 110  * Returns zero, a negative errno, or a negative NFS4ERR status.
 111  * If zero is returned, an nfs_client pointer is planted in
 112  * "result".
 113  *
 114  * Note: The returned client may not yet be marked ready.
 115  */
 116 int nfs40_discover_server_trunking(struct nfs_client *clp,
 117                                    struct nfs_client **result,
 118                                    struct rpc_cred *cred)
 119 {
 120         struct nfs4_setclientid_res clid = {
 121                 .clientid = clp->cl_clientid,
 122                 .confirm = clp->cl_confirm,
 123         };
 124         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 125         unsigned short port;
 126         int status;
 127
 128         port = nn->nfs_callback_tcpport;
 129         if (clp->cl_addr.ss_family == AF_INET6)
 130                 port = nn->nfs_callback_tcpport6;
 131
 132         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
 133         if (status != 0)
 134                 goto out;
 135         clp->cl_clientid = clid.clientid;
 136         clp->cl_confirm = clid.confirm;
 137
 138         status = nfs40_walk_client_list(clp, result, cred);
 139         if (status == 0) {
 140                 /* Sustain the lease, even if it's empty.  If the clientid4
 141                  * goes stale it's of no use for trunking discovery. */
 142                 nfs4_schedule_state_renewal(*result);
 143         }
 144 out:
 145         return status;
 146 }
 147
 148 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
 149 {
 150         struct rpc_cred *cred = NULL;
 151
 152         if (clp->cl_machine_cred != NULL)
 153                 cred = get_rpccred(clp->cl_machine_cred);
 154         return cred;
 155 }
 156
 157 static void nfs4_root_machine_cred(struct nfs_client *clp)
 158 {
 159         struct rpc_cred *cred, *new;
 160
 161         new = rpc_lookup_machine_cred(NULL);
 162         spin_lock(&clp->cl_lock);
 163         cred = clp->cl_machine_cred;
 164         clp->cl_machine_cred = new;
 165         spin_unlock(&clp->cl_lock);
 166         if (cred != NULL)
 167                 put_rpccred(cred);
 168 }
 169
 170 static struct rpc_cred *
 171 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 172 {
 173         struct rpc_cred *cred = NULL;
 174         struct nfs4_state_owner *sp;
 175         struct rb_node *pos;
 176
 177         for (pos = rb_first(&server->state_owners);
 178              pos != NULL;
 179              pos = rb_next(pos)) {
 180                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 181                 if (list_empty(&sp->so_states))
 182                         continue;
 183                 cred = get_rpccred(sp->so_cred);
 184                 break;
 185         }
 186         return cred;
 187 }
 188
 189 /**
 190  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
 191  * @clp: client state handle
 192  *
 193  * Returns an rpc_cred with reference count bumped, or NULL.
 194  * Caller must hold clp->cl_lock.
 195  */
 196 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 197 {
 198         struct rpc_cred *cred = NULL;
 199         struct nfs_server *server;
 200
 201         /* Use machine credentials if available */
 202         cred = nfs4_get_machine_cred_locked(clp);
 203         if (cred != NULL)
 204                 goto out;
 205
 206         rcu_read_lock();
 207         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 208                 cred = nfs4_get_renew_cred_server_locked(server);
 209                 if (cred != NULL)
 210                         break;
 211         }
 212         rcu_read_unlock();
 213
 214 out:
 215         return cred;
 216 }
 217
 218 static void nfs4_end_drain_slot_table(struct nfs4_slot_table *tbl)
 219 {
 220         if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
 221                 spin_lock(&tbl->slot_tbl_lock);
 222                 nfs41_wake_slot_table(tbl);
 223                 spin_unlock(&tbl->slot_tbl_lock);
 224         }
 225 }
 226
 227 static void nfs4_end_drain_session(struct nfs_client *clp)
 228 {
 229         struct nfs4_session *ses = clp->cl_session;
 230
 231         if (clp->cl_slot_tbl) {
 232                 nfs4_end_drain_slot_table(clp->cl_slot_tbl);
 233                 return;
 234         }
 235
 236         if (ses != NULL) {
 237                 nfs4_end_drain_slot_table(&ses->bc_slot_table);
 238                 nfs4_end_drain_slot_table(&ses->fc_slot_table);
 239         }
 240 }
 241
 242 static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
 243 {
 244         set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
 245         spin_lock(&tbl->slot_tbl_lock);
 246         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
 247                 reinit_completion(&tbl->complete);
 248                 spin_unlock(&tbl->slot_tbl_lock);
 249                 return wait_for_completion_interruptible(&tbl->complete);
 250         }
 251         spin_unlock(&tbl->slot_tbl_lock);
 252         return 0;
 253 }
 254
 255 static int nfs4_begin_drain_session(struct nfs_client *clp)
 256 {
 257         struct nfs4_session *ses = clp->cl_session;
 258         int ret = 0;
 259
 260         if (clp->cl_slot_tbl)
 261                 return nfs4_drain_slot_tbl(clp->cl_slot_tbl);
 262
 263         /* back channel */
 264         ret = nfs4_drain_slot_tbl(&ses->bc_slot_table);
 265         if (ret)
 266                 return ret;
 267         /* fore channel */
 268         return nfs4_drain_slot_tbl(&ses->fc_slot_table);
 269 }
 270
 271 #if defined(CONFIG_NFS_V4_1)
 272
 273 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 274 {
 275         int status;
 276         struct nfs_fsinfo fsinfo;
 277
 278         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
 279                 nfs4_schedule_state_renewal(clp);
 280                 return 0;
 281         }
 282
 283         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 284         if (status == 0) {
 285                 /* Update lease time and schedule renewal */
 286                 spin_lock(&clp->cl_lock);
 287                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 288                 clp->cl_last_renewal = jiffies;
 289                 spin_unlock(&clp->cl_lock);
 290
 291                 nfs4_schedule_state_renewal(clp);
 292         }
 293
 294         return status;
 295 }
 296
 297 static void nfs41_finish_session_reset(struct nfs_client *clp)
 298 {
 299         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 300         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
 301         /* create_session negotiated new slot table */
 302         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
 303         nfs41_setup_state_renewal(clp);
 304 }
 305
 306 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 307 {
 308         int status;
 309
 310         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 311                 goto do_confirm;
 312         nfs4_begin_drain_session(clp);
 313         status = nfs4_proc_exchange_id(clp, cred);
 314         if (status != 0)
 315                 goto out;
 316         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 317 do_confirm:
 318         status = nfs4_proc_create_session(clp, cred);
 319         if (status != 0)
 320                 goto out;
 321         nfs41_finish_session_reset(clp);
 322         nfs_mark_client_ready(clp, NFS_CS_READY);
 323 out:
 324         return status;
 325 }
 326
 327 /**
 328  * nfs41_discover_server_trunking - Detect server IP address trunking (mv1)
 329  *
 330  * @clp: nfs_client under test
 331  * @result: OUT: found nfs_client, or clp
 332  * @cred: credential to use for trunking test
 333  *
 334  * Returns NFS4_OK, a negative errno, or a negative NFS4ERR status.
 335  * If NFS4_OK is returned, an nfs_client pointer is planted in
 336  * "result".
 337  *
 338  * Note: The returned client may not yet be marked ready.
 339  */
 340 int nfs41_discover_server_trunking(struct nfs_client *clp,
 341                                    struct nfs_client **result,
 342                                    struct rpc_cred *cred)
 343 {
 344         int status;
 345
 346         status = nfs4_proc_exchange_id(clp, cred);
 347         if (status != NFS4_OK)
 348                 return status;
 349         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 350
 351         return nfs41_walk_client_list(clp, result, cred);
 352 }
 353
 354 #endif /* CONFIG_NFS_V4_1 */
 355
 356 /**
 357  * nfs4_get_clid_cred - Acquire credential for a setclientid operation
 358  * @clp: client state handle
 359  *
 360  * Returns an rpc_cred with reference count bumped, or NULL.
 361  */
 362 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp)
 363 {
 364         struct rpc_cred *cred;
 365
 366         spin_lock(&clp->cl_lock);
 367         cred = nfs4_get_machine_cred_locked(clp);
 368         spin_unlock(&clp->cl_lock);
 369         return cred;
 370 }
 371
 372 static struct nfs4_state_owner *
 373 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
 374 {
 375         struct rb_node **p = &server->state_owners.rb_node,
 376                        *parent = NULL;
 377         struct nfs4_state_owner *sp;
 378
 379         while (*p != NULL) {
 380                 parent = *p;
 381                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 382
 383                 if (cred < sp->so_cred)
 384                         p = &parent->rb_left;
 385                 else if (cred > sp->so_cred)
 386                         p = &parent->rb_right;
 387                 else {
 388                         if (!list_empty(&sp->so_lru))
 389                                 list_del_init(&sp->so_lru);
 390                         atomic_inc(&sp->so_count);
 391                         return sp;
 392                 }
 393         }
 394         return NULL;
 395 }
 396
 397 static struct nfs4_state_owner *
 398 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 399 {
 400         struct nfs_server *server = new->so_server;
 401         struct rb_node **p = &server->state_owners.rb_node,
 402                        *parent = NULL;
 403         struct nfs4_state_owner *sp;
 404         int err;
 405
 406         while (*p != NULL) {
 407                 parent = *p;
 408                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 409
 410                 if (new->so_cred < sp->so_cred)
 411                         p = &parent->rb_left;
 412                 else if (new->so_cred > sp->so_cred)
 413                         p = &parent->rb_right;
 414                 else {
 415                         if (!list_empty(&sp->so_lru))
 416                                 list_del_init(&sp->so_lru);
 417                         atomic_inc(&sp->so_count);
 418                         return sp;
 419                 }
 420         }
 421         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
 422         if (err)
 423                 return ERR_PTR(err);
 424         rb_link_node(&new->so_server_node, parent, p);
 425         rb_insert_color(&new->so_server_node, &server->state_owners);
 426         return new;
 427 }
 428
 429 static void
 430 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 431 {
 432         struct nfs_server *server = sp->so_server;
 433
 434         if (!RB_EMPTY_NODE(&sp->so_server_node))
 435                 rb_erase(&sp->so_server_node, &server->state_owners);
 436         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
 437 }
 438
 439 static void
 440 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
 441 {
 442         sc->create_time = ktime_get();
 443         sc->flags = 0;
 444         sc->counter = 0;
 445         spin_lock_init(&sc->lock);
 446         INIT_LIST_HEAD(&sc->list);
 447         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
 448 }
 449
 450 static void
 451 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
 452 {
 453         rpc_destroy_wait_queue(&sc->wait);
 454 }
 455
 456 /*
 457  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 458  * create a new state_owner.
 459  *
 460  */
 461 static struct nfs4_state_owner *
 462 nfs4_alloc_state_owner(struct nfs_server *server,
 463                 struct rpc_cred *cred,
 464                 gfp_t gfp_flags)
 465 {
 466         struct nfs4_state_owner *sp;
 467
 468         sp = kzalloc(sizeof(*sp), gfp_flags);
 469         if (!sp)
 470                 return NULL;
 471         sp->so_server = server;
 472         sp->so_cred = get_rpccred(cred);
 473         spin_lock_init(&sp->so_lock);
 474         INIT_LIST_HEAD(&sp->so_states);
 475         nfs4_init_seqid_counter(&sp->so_seqid);
 476         atomic_set(&sp->so_count, 1);
 477         INIT_LIST_HEAD(&sp->so_lru);
 478         seqcount_init(&sp->so_reclaim_seqcount);
 479         mutex_init(&sp->so_delegreturn_mutex);
 480         return sp;
 481 }
 482
 483 static void
 484 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 485 {
 486         struct rb_node *rb_node = &sp->so_server_node;
 487
 488         if (!RB_EMPTY_NODE(rb_node)) {
 489                 struct nfs_server *server = sp->so_server;
 490                 struct nfs_client *clp = server->nfs_client;
 491
 492                 spin_lock(&clp->cl_lock);
 493                 if (!RB_EMPTY_NODE(rb_node)) {
 494                         rb_erase(rb_node, &server->state_owners);
 495                         RB_CLEAR_NODE(rb_node);
 496                 }
 497                 spin_unlock(&clp->cl_lock);
 498         }
 499 }
 500
 501 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 502 {
 503         nfs4_destroy_seqid_counter(&sp->so_seqid);
 504         put_rpccred(sp->so_cred);
 505         kfree(sp);
 506 }
 507
 508 static void nfs4_gc_state_owners(struct nfs_server *server)
 509 {
 510         struct nfs_client *clp = server->nfs_client;
 511         struct nfs4_state_owner *sp, *tmp;
 512         unsigned long time_min, time_max;
 513         LIST_HEAD(doomed);
 514
 515         spin_lock(&clp->cl_lock);
 516         time_max = jiffies;
 517         time_min = (long)time_max - (long)clp->cl_lease_time;
 518         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 519                 /* NB: LRU is sorted so that oldest is at the head */
 520                 if (time_in_range(sp->so_expires, time_min, time_max))
 521                         break;
 522                 list_move(&sp->so_lru, &doomed);
 523                 nfs4_remove_state_owner_locked(sp);
 524         }
 525         spin_unlock(&clp->cl_lock);
 526
 527         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 528                 list_del(&sp->so_lru);
 529                 nfs4_free_state_owner(sp);
 530         }
 531 }
 532
 533 /**
 534  * nfs4_get_state_owner - Look up a state owner given a credential
 535  * @server: nfs_server to search
 536  * @cred: RPC credential to match
 537  *
 538  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 539  */
 540 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 541                                               struct rpc_cred *cred,
 542                                               gfp_t gfp_flags)
 543 {
 544         struct nfs_client *clp = server->nfs_client;
 545         struct nfs4_state_owner *sp, *new;
 546
 547         spin_lock(&clp->cl_lock);
 548         sp = nfs4_find_state_owner_locked(server, cred);
 549         spin_unlock(&clp->cl_lock);
 550         if (sp != NULL)
 551                 goto out;
 552         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 553         if (new == NULL)
 554                 goto out;
 555         do {
 556                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
 557                         break;
 558                 spin_lock(&clp->cl_lock);
 559                 sp = nfs4_insert_state_owner_locked(new);
 560                 spin_unlock(&clp->cl_lock);
 561         } while (sp == ERR_PTR(-EAGAIN));
 562         if (sp != new)
 563                 nfs4_free_state_owner(new);
 564 out:
 565         nfs4_gc_state_owners(server);
 566         return sp;
 567 }
 568
 569 /**
 570  * nfs4_put_state_owner - Release a nfs4_state_owner
 571  * @sp: state owner data to release
 572  *
 573  * Note that we keep released state owners on an LRU
 574  * list.
 575  * This caches valid state owners so that they can be
 576  * reused, to avoid the OPEN_CONFIRM on minor version 0.
 577  * It also pins the uniquifier of dropped state owners for
 578  * a while, to ensure that those state owner names are
 579  * never reused.
 580  */
 581 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 582 {
 583         struct nfs_server *server = sp->so_server;
 584         struct nfs_client *clp = server->nfs_client;
 585
 586         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 587                 return;
 588
 589         sp->so_expires = jiffies;
 590         list_add_tail(&sp->so_lru, &server->state_owners_lru);
 591         spin_unlock(&clp->cl_lock);
 592 }
 593
 594 /**
 595  * nfs4_purge_state_owners - Release all cached state owners
 596  * @server: nfs_server with cached state owners to release
 597  *
 598  * Called at umount time.  Remaining state owners will be on
 599  * the LRU with ref count of zero.
 600  */
 601 void nfs4_purge_state_owners(struct nfs_server *server)
 602 {
 603         struct nfs_client *clp = server->nfs_client;
 604         struct nfs4_state_owner *sp, *tmp;
 605         LIST_HEAD(doomed);
 606
 607         spin_lock(&clp->cl_lock);
 608         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 609                 list_move(&sp->so_lru, &doomed);
 610                 nfs4_remove_state_owner_locked(sp);
 611         }
 612         spin_unlock(&clp->cl_lock);
 613
 614         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 615                 list_del(&sp->so_lru);
 616                 nfs4_free_state_owner(sp);
 617         }
 618 }
 619
 620 static struct nfs4_state *
 621 nfs4_alloc_open_state(void)
 622 {
 623         struct nfs4_state *state;
 624
 625         state = kzalloc(sizeof(*state), GFP_NOFS);
 626         if (!state)
 627                 return NULL;
 628         atomic_set(&state->count, 1);
 629         INIT_LIST_HEAD(&state->lock_states);
 630         spin_lock_init(&state->state_lock);
 631         seqlock_init(&state->seqlock);
 632         return state;
 633 }
 634
 635 void
 636 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 637 {
 638         if (state->state == fmode)
 639                 return;
 640         /* NB! List reordering - see the reclaim code for why.  */
 641         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 642                 if (fmode & FMODE_WRITE)
 643                         list_move(&state->open_states, &state->owner->so_states);
 644                 else
 645                         list_move_tail(&state->open_states, &state->owner->so_states);
 646         }
 647         state->state = fmode;
 648 }
 649
 650 static struct nfs4_state *
 651 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 652 {
 653         struct nfs_inode *nfsi = NFS_I(inode);
 654         struct nfs4_state *state;
 655
 656         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 657                 if (state->owner != owner)
 658                         continue;
 659                 if (!nfs4_valid_open_stateid(state))
 660                         continue;
 661                 if (atomic_inc_not_zero(&state->count))
 662                         return state;
 663         }
 664         return NULL;
 665 }
 666
 667 static void
 668 nfs4_free_open_state(struct nfs4_state *state)
 669 {
 670         kfree(state);
 671 }
 672
 673 struct nfs4_state *
 674 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 675 {
 676         struct nfs4_state *state, *new;
 677         struct nfs_inode *nfsi = NFS_I(inode);
 678
 679         spin_lock(&inode->i_lock);
 680         state = __nfs4_find_state_byowner(inode, owner);
 681         spin_unlock(&inode->i_lock);
 682         if (state)
 683                 goto out;
 684         new = nfs4_alloc_open_state();
 685         spin_lock(&owner->so_lock);
 686         spin_lock(&inode->i_lock);
 687         state = __nfs4_find_state_byowner(inode, owner);
 688         if (state == NULL && new != NULL) {
 689                 state = new;
 690                 state->owner = owner;
 691                 atomic_inc(&owner->so_count);
 692                 list_add(&state->inode_states, &nfsi->open_states);
 693                 ihold(inode);
 694                 state->inode = inode;
 695                 spin_unlock(&inode->i_lock);
 696                 /* Note: The reclaim code dictates that we add stateless
 697                  * and read-only stateids to the end of the list */
 698                 list_add_tail(&state->open_states, &owner->so_states);
 699                 spin_unlock(&owner->so_lock);
 700         } else {
 701                 spin_unlock(&inode->i_lock);
 702                 spin_unlock(&owner->so_lock);
 703                 if (new)
 704                         nfs4_free_open_state(new);
 705         }
 706 out:
 707         return state;
 708 }
 709
 710 void nfs4_put_open_state(struct nfs4_state *state)
 711 {
 712         struct inode *inode = state->inode;
 713         struct nfs4_state_owner *owner = state->owner;
 714
 715         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 716                 return;
 717         spin_lock(&inode->i_lock);
 718         list_del(&state->inode_states);
 719         list_del(&state->open_states);
 720         spin_unlock(&inode->i_lock);
 721         spin_unlock(&owner->so_lock);
 722         iput(inode);
 723         nfs4_free_open_state(state);
 724         nfs4_put_state_owner(owner);
 725 }
 726
 727 /*
 728  * Close the current file.
 729  */
 730 static void __nfs4_close(struct nfs4_state *state,
 731                 fmode_t fmode, gfp_t gfp_mask, int wait)
 732 {
 733         struct nfs4_state_owner *owner = state->owner;
 734         int call_close = 0;
 735         fmode_t newstate;
 736
 737         atomic_inc(&owner->so_count);
 738         /* Protect against nfs4_find_state() */
 739         spin_lock(&owner->so_lock);
 740         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 741                 case FMODE_READ:
 742                         state->n_rdonly--;
 743                         break;
 744                 case FMODE_WRITE:
 745                         state->n_wronly--;
 746                         break;
 747                 case FMODE_READ|FMODE_WRITE:
 748                         state->n_rdwr--;
 749         }
 750         newstate = FMODE_READ|FMODE_WRITE;
 751         if (state->n_rdwr == 0) {
 752                 if (state->n_rdonly == 0) {
 753                         newstate &= ~FMODE_READ;
 754                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 755                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 756                 }
 757                 if (state->n_wronly == 0) {
 758                         newstate &= ~FMODE_WRITE;
 759                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 760                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 761                 }
 762                 if (newstate == 0)
 763                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 764         }
 765         nfs4_state_set_mode_locked(state, newstate);
 766         spin_unlock(&owner->so_lock);
 767
 768         if (!call_close) {
 769                 nfs4_put_open_state(state);
 770                 nfs4_put_state_owner(owner);
 771         } else
 772                 nfs4_do_close(state, gfp_mask, wait);
 773 }
 774
 775 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 776 {
 777         __nfs4_close(state, fmode, GFP_NOFS, 0);
 778 }
 779
 780 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 781 {
 782         __nfs4_close(state, fmode, GFP_KERNEL, 1);
 783 }
 784
 785 /*
 786  * Search the state->lock_states for an existing lock_owner
 787  * that is compatible with current->files
 788  */
 789 static struct nfs4_lock_state *
 790 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 791 {
 792         struct nfs4_lock_state *pos;
 793         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 794                 if (pos->ls_owner != fl_owner)
 795                         continue;
 796                 atomic_inc(&pos->ls_count);
 797                 return pos;
 798         }
 799         return NULL;
 800 }
 801
 802 /*
 803  * Return a compatible lock_state. If no initialized lock_state structure
 804  * exists, return an uninitialized one.
 805  *
 806  */
 807 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 808 {
 809         struct nfs4_lock_state *lsp;
 810         struct nfs_server *server = state->owner->so_server;
 811
 812         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 813         if (lsp == NULL)
 814                 return NULL;
 815         nfs4_init_seqid_counter(&lsp->ls_seqid);
 816         atomic_set(&lsp->ls_count, 1);
 817         lsp->ls_state = state;
 818         lsp->ls_owner = fl_owner;
 819         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
 820         if (lsp->ls_seqid.owner_id < 0)
 821                 goto out_free;
 822         INIT_LIST_HEAD(&lsp->ls_locks);
 823         return lsp;
 824 out_free:
 825         kfree(lsp);
 826         return NULL;
 827 }
 828
 829 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
 830 {
 831         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
 832         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
 833         kfree(lsp);
 834 }
 835
 836 /*
 837  * Return a compatible lock_state. If no initialized lock_state structure
 838  * exists, return an uninitialized one.
 839  *
 840  */
 841 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 842 {
 843         struct nfs4_lock_state *lsp, *new = NULL;
 844
 845         for(;;) {
 846                 spin_lock(&state->state_lock);
 847                 lsp = __nfs4_find_lock_state(state, owner);
 848                 if (lsp != NULL)
 849                         break;
 850                 if (new != NULL) {
 851                         list_add(&new->ls_locks, &state->lock_states);
 852                         set_bit(LK_STATE_IN_USE, &state->flags);
 853                         lsp = new;
 854                         new = NULL;
 855                         break;
 856                 }
 857                 spin_unlock(&state->state_lock);
 858                 new = nfs4_alloc_lock_state(state, owner);
 859                 if (new == NULL)
 860                         return NULL;
 861         }
 862         spin_unlock(&state->state_lock);
 863         if (new != NULL)
 864                 nfs4_free_lock_state(state->owner->so_server, new);
 865         return lsp;
 866 }
 867
 868 /*
 869  * Release reference to lock_state, and free it if we see that
 870  * it is no longer in use
 871  */
 872 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 873 {
 874         struct nfs_server *server;
 875         struct nfs4_state *state;
 876
 877         if (lsp == NULL)
 878                 return;
 879         state = lsp->ls_state;
 880         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 881                 return;
 882         list_del(&lsp->ls_locks);
 883         if (list_empty(&state->lock_states))
 884                 clear_bit(LK_STATE_IN_USE, &state->flags);
 885         spin_unlock(&state->state_lock);
 886         server = state->owner->so_server;
 887         if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
 888                 struct nfs_client *clp = server->nfs_client;
 889
 890                 clp->cl_mvops->free_lock_state(server, lsp);
 891         } else
 892                 nfs4_free_lock_state(server, lsp);
 893 }
 894
 895 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 896 {
 897         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 898
 899         dst->fl_u.nfs4_fl.owner = lsp;
 900         atomic_inc(&lsp->ls_count);
 901 }
 902
 903 static void nfs4_fl_release_lock(struct file_lock *fl)
 904 {
 905         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 906 }
 907
 908 static const struct file_lock_operations nfs4_fl_lock_ops = {
 909         .fl_copy_lock = nfs4_fl_copy_lock,
 910         .fl_release_private = nfs4_fl_release_lock,
 911 };
 912
 913 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 914 {
 915         struct nfs4_lock_state *lsp;
 916
 917         if (fl->fl_ops != NULL)
 918                 return 0;
 919         lsp = nfs4_get_lock_state(state, fl->fl_owner);
 920         if (lsp == NULL)
 921                 return -ENOMEM;
 922         fl->fl_u.nfs4_fl.owner = lsp;
 923         fl->fl_ops = &nfs4_fl_lock_ops;
 924         return 0;
 925 }
 926
 927 static int nfs4_copy_lock_stateid(nfs4_stateid *dst,
 928                 struct nfs4_state *state,
 929                 const struct nfs_lockowner *lockowner)
 930 {
 931         struct nfs4_lock_state *lsp;
 932         fl_owner_t fl_owner;
 933         int ret = -ENOENT;
 934
 935
 936         if (lockowner == NULL)
 937                 goto out;
 938
 939         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
 940                 goto out;
 941
 942         fl_owner = lockowner->l_owner;
 943         spin_lock(&state->state_lock);
 944         lsp = __nfs4_find_lock_state(state, fl_owner);
 945         if (lsp && test_bit(NFS_LOCK_LOST, &lsp->ls_flags))
 946                 ret = -EIO;
 947         else if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
 948                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
 949                 ret = 0;
 950         }
 951         spin_unlock(&state->state_lock);
 952         nfs4_put_lock_state(lsp);
 953 out:
 954         return ret;
 955 }
 956
 957 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
 958 {
 959         const nfs4_stateid *src;
 960         int seq;
 961
 962         do {
 963                 src = &zero_stateid;
 964                 seq = read_seqbegin(&state->seqlock);
 965                 if (test_bit(NFS_OPEN_STATE, &state->flags))
 966                         src = &state->open_stateid;
 967                 nfs4_stateid_copy(dst, src);
 968         } while (read_seqretry(&state->seqlock, seq));
 969 }
 970
 971 /*
 972  * Byte-range lock aware utility to initialize the stateid of read/write
 973  * requests.
 974  */
 975 int nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
 976                 fmode_t fmode, const struct nfs_lockowner *lockowner)
 977 {
 978         int ret = nfs4_copy_lock_stateid(dst, state, lockowner);
 979         if (ret == -EIO)
 980                 /* A lost lock - don't even consider delegations */
 981                 goto out;
 982         /* returns true if delegation stateid found and copied */
 983         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode)) {
 984                 ret = 0;
 985                 goto out;
 986         }
 987         if (ret != -ENOENT)
 988                 /* nfs4_copy_delegation_stateid() didn't over-write
 989                  * dst, so it still has the lock stateid which we now
 990                  * choose to use.
 991                  */
 992                 goto out;
 993         nfs4_copy_open_stateid(dst, state);
 994         ret = 0;
 995 out:
 996         if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41))
 997                 dst->seqid = 0;
 998         return ret;
 999 }
1000
1001 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
1002 {
1003         struct nfs_seqid *new;
1004
1005         new = kmalloc(sizeof(*new), gfp_mask);
1006         if (new != NULL) {
1007                 new->sequence = counter;
1008                 INIT_LIST_HEAD(&new->list);
1009                 new->task = NULL;
1010         }
1011         return new;
1012 }
1013
1014 void nfs_release_seqid(struct nfs_seqid *seqid)
1015 {
1016         struct nfs_seqid_counter *sequence;
1017
1018         if (list_empty(&seqid->list))
1019                 return;
1020         sequence = seqid->sequence;
1021         spin_lock(&sequence->lock);
1022         list_del_init(&seqid->list);
1023         if (!list_empty(&sequence->list)) {
1024                 struct nfs_seqid *next;
1025
1026                 next = list_first_entry(&sequence->list,
1027                                 struct nfs_seqid, list);
1028                 rpc_wake_up_queued_task(&sequence->wait, next->task);
1029         }
1030         spin_unlock(&sequence->lock);
1031 }
1032
1033 void nfs_free_seqid(struct nfs_seqid *seqid)
1034 {
1035         nfs_release_seqid(seqid);
1036         kfree(seqid);
1037 }
1038
1039 /*
1040  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
1041  * failed with a seqid incrementing error -
1042  * see comments nfs4.h:seqid_mutating_error()
1043  */
1044 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
1045 {
1046         switch (status) {
1047                 case 0:
1048                         break;
1049                 case -NFS4ERR_BAD_SEQID:
1050                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1051                                 return;
1052                         pr_warn_ratelimited("NFS: v4 server returned a bad"
1053                                         " sequence-id error on an"
1054                                         " unconfirmed sequence %p!\n",
1055                                         seqid->sequence);
1056                 case -NFS4ERR_STALE_CLIENTID:
1057                 case -NFS4ERR_STALE_STATEID:
1058                 case -NFS4ERR_BAD_STATEID:
1059                 case -NFS4ERR_BADXDR:
1060                 case -NFS4ERR_RESOURCE:
1061                 case -NFS4ERR_NOFILEHANDLE:
1062                         /* Non-seqid mutating errors */
1063                         return;
1064         };
1065         /*
1066          * Note: no locking needed as we are guaranteed to be first
1067          * on the sequence list
1068          */
1069         seqid->sequence->counter++;
1070 }
1071
1072 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1073 {
1074         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1075                                         struct nfs4_state_owner, so_seqid);
1076         struct nfs_server *server = sp->so_server;
1077
1078         if (status == -NFS4ERR_BAD_SEQID)
1079                 nfs4_drop_state_owner(sp);
1080         if (!nfs4_has_session(server->nfs_client))
1081                 nfs_increment_seqid(status, seqid);
1082 }
1083
1084 /*
1085  * Increment the seqid if the LOCK/LOCKU succeeded, or
1086  * failed with a seqid incrementing error -
1087  * see comments nfs4.h:seqid_mutating_error()
1088  */
1089 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1090 {
1091         nfs_increment_seqid(status, seqid);
1092 }
1093
1094 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1095 {
1096         struct nfs_seqid_counter *sequence = seqid->sequence;
1097         int status = 0;
1098
1099         spin_lock(&sequence->lock);
1100         seqid->task = task;
1101         if (list_empty(&seqid->list))
1102                 list_add_tail(&seqid->list, &sequence->list);
1103         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1104                 goto unlock;
1105         rpc_sleep_on(&sequence->wait, task, NULL);
1106         status = -EAGAIN;
1107 unlock:
1108         spin_unlock(&sequence->lock);
1109         return status;
1110 }
1111
1112 static int nfs4_run_state_manager(void *);
1113
1114 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1115 {
1116         smp_mb__before_atomic();
1117         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1118         smp_mb__after_atomic();
1119         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1120         rpc_wake_up(&clp->cl_rpcwaitq);
1121 }
1122
1123 /*
1124  * Schedule the nfs_client asynchronous state management routine
1125  */
1126 void nfs4_schedule_state_manager(struct nfs_client *clp)
1127 {
1128         struct task_struct *task;
1129         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1130
1131         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1132                 return;
1133         __module_get(THIS_MODULE);
1134         atomic_inc(&clp->cl_count);
1135
1136         /* The rcu_read_lock() is not strictly necessary, as the state
1137          * manager is the only thread that ever changes the rpc_xprt
1138          * after it's initialized.  At this point, we're single threaded. */
1139         rcu_read_lock();
1140         snprintf(buf, sizeof(buf), "%s-manager",
1141                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1142         rcu_read_unlock();
1143         task = kthread_run(nfs4_run_state_manager, clp, "%s", buf);
1144         if (IS_ERR(task)) {
1145                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1146                         __func__, PTR_ERR(task));
1147                 nfs4_clear_state_manager_bit(clp);
1148                 nfs_put_client(clp);
1149                 module_put(THIS_MODULE);
1150         }
1151 }
1152
1153 /*
1154  * Schedule a lease recovery attempt
1155  */
1156 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1157 {
1158         if (!clp)
1159                 return;
1160         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1161                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1162         dprintk("%s: scheduling lease recovery for server %s\n", __func__,
1163                         clp->cl_hostname);
1164         nfs4_schedule_state_manager(clp);
1165 }
1166 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1167
1168 /**
1169  * nfs4_schedule_migration_recovery - trigger migration recovery
1170  *
1171  * @server: FSID that is migrating
1172  *
1173  * Returns zero if recovery has started, otherwise a negative NFS4ERR
1174  * value is returned.
1175  */
1176 int nfs4_schedule_migration_recovery(const struct nfs_server *server)
1177 {
1178         struct nfs_client *clp = server->nfs_client;
1179
1180         if (server->fh_expire_type != NFS4_FH_PERSISTENT) {
1181                 pr_err("NFS: volatile file handles not supported (server %s)\n",
1182                                 clp->cl_hostname);
1183                 return -NFS4ERR_IO;
1184         }
1185
1186         if (test_bit(NFS_MIG_FAILED, &server->mig_status))
1187                 return -NFS4ERR_IO;
1188
1189         dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n",
1190                         __func__,
1191                         (unsigned long long)server->fsid.major,
1192                         (unsigned long long)server->fsid.minor,
1193                         clp->cl_hostname);
1194
1195         set_bit(NFS_MIG_IN_TRANSITION,
1196                         &((struct nfs_server *)server)->mig_status);
1197         set_bit(NFS4CLNT_MOVED, &clp->cl_state);
1198
1199         nfs4_schedule_state_manager(clp);
1200         return 0;
1201 }
1202 EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
1203
1204 /**
1205  * nfs4_schedule_lease_moved_recovery - start lease-moved recovery
1206  *
1207  * @clp: server to check for moved leases
1208  *
1209  */
1210 void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp)
1211 {
1212         dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n",
1213                 __func__, clp->cl_clientid, clp->cl_hostname);
1214
1215         set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state);
1216         nfs4_schedule_state_manager(clp);
1217 }
1218 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery);
1219
1220 int nfs4_wait_clnt_recover(struct nfs_client *clp)
1221 {
1222         int res;
1223
1224         might_sleep();
1225
1226         atomic_inc(&clp->cl_count);
1227         res = wait_on_bit_action(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
1228                                  nfs_wait_bit_killable, TASK_KILLABLE);
1229         if (res)
1230                 goto out;
1231         if (clp->cl_cons_state < 0)
1232                 res = clp->cl_cons_state;
1233 out:
1234         nfs_put_client(clp);
1235         return res;
1236 }
1237
1238 int nfs4_client_recover_expired_lease(struct nfs_client *clp)
1239 {
1240         unsigned int loop;
1241         int ret;
1242
1243         for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) {
1244                 ret = nfs4_wait_clnt_recover(clp);
1245                 if (ret != 0)
1246                         break;
1247                 if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) &&
1248                     !test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state))
1249                         break;
1250                 nfs4_schedule_state_manager(clp);
1251                 ret = -EIO;
1252         }
1253         return ret;
1254 }
1255
1256 /*
1257  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1258  * @clp: client to process
1259  *
1260  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1261  * resend of the SETCLIENTID and hence re-establish the
1262  * callback channel. Then return all existing delegations.
1263  */
1264 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1265 {
1266         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1267         nfs_expire_all_delegations(clp);
1268         dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__,
1269                         clp->cl_hostname);
1270 }
1271
1272 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1273 {
1274         nfs40_handle_cb_pathdown(clp);
1275         nfs4_schedule_state_manager(clp);
1276 }
1277
1278 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1279 {
1280
1281         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1282         /* Don't recover state that expired before the reboot */
1283         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1284                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1285                 return 0;
1286         }
1287         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1288         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1289         return 1;
1290 }
1291
1292 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1293 {
1294         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1295         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1296         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1297         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1298         return 1;
1299 }
1300
1301 int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1302 {
1303         struct nfs_client *clp = server->nfs_client;
1304
1305         if (!nfs4_valid_open_stateid(state))
1306                 return -EBADF;
1307         nfs4_state_mark_reclaim_nograce(clp, state);
1308         dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
1309                         clp->cl_hostname);
1310         nfs4_schedule_state_manager(clp);
1311         return 0;
1312 }
1313 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1314
1315 void nfs_inode_find_state_and_recover(struct inode *inode,
1316                 const nfs4_stateid *stateid)
1317 {
1318         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1319         struct nfs_inode *nfsi = NFS_I(inode);
1320         struct nfs_open_context *ctx;
1321         struct nfs4_state *state;
1322         bool found = false;
1323
1324         spin_lock(&inode->i_lock);
1325         list_for_each_entry(ctx, &nfsi->open_files, list) {
1326                 state = ctx->state;
1327                 if (state == NULL)
1328                         continue;
1329                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1330                         continue;
1331                 if (!nfs4_stateid_match(&state->stateid, stateid))
1332                         continue;
1333                 nfs4_state_mark_reclaim_nograce(clp, state);
1334                 found = true;
1335         }
1336         spin_unlock(&inode->i_lock);
1337         if (found)
1338                 nfs4_schedule_state_manager(clp);
1339 }
1340
1341 static void nfs4_state_mark_open_context_bad(struct nfs4_state *state)
1342 {
1343         struct inode *inode = state->inode;
1344         struct nfs_inode *nfsi = NFS_I(inode);
1345         struct nfs_open_context *ctx;
1346
1347         spin_lock(&inode->i_lock);
1348         list_for_each_entry(ctx, &nfsi->open_files, list) {
1349                 if (ctx->state != state)
1350                         continue;
1351                 set_bit(NFS_CONTEXT_BAD, &ctx->flags);
1352         }
1353         spin_unlock(&inode->i_lock);
1354 }
1355
1356 static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)
1357 {
1358         set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags);
1359         nfs4_state_mark_open_context_bad(state);
1360 }
1361
1362
1363 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1364 {
1365         struct inode *inode = state->inode;
1366         struct nfs_inode *nfsi = NFS_I(inode);
1367         struct file_lock *fl;
1368         int status = 0;
1369
1370         if (inode->i_flock == NULL)
1371                 return 0;
1372
1373         /* Guard against delegation returns and new lock/unlock calls */
1374         down_write(&nfsi->rwsem);
1375         /* Protect inode->i_flock using the BKL */
1376         spin_lock(&inode->i_lock);
1377         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1378                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1379                         continue;
1380                 if (nfs_file_open_context(fl->fl_file)->state != state)
1381                         continue;
1382                 spin_unlock(&inode->i_lock);
1383                 status = ops->recover_lock(state, fl);
1384                 switch (status) {
1385                         case 0:
1386                                 break;
1387                         case -ESTALE:
1388                         case -NFS4ERR_ADMIN_REVOKED:
1389                         case -NFS4ERR_STALE_STATEID:
1390                         case -NFS4ERR_BAD_STATEID:
1391                         case -NFS4ERR_EXPIRED:
1392                         case -NFS4ERR_NO_GRACE:
1393                         case -NFS4ERR_STALE_CLIENTID:
1394                         case -NFS4ERR_BADSESSION:
1395                         case -NFS4ERR_BADSLOT:
1396                         case -NFS4ERR_BAD_HIGH_SLOT:
1397                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1398                                 goto out;
1399                         default:
1400                                 printk(KERN_ERR "NFS: %s: unhandled error %d\n",
1401                                          __func__, status);
1402                         case -ENOMEM:
1403                         case -NFS4ERR_DENIED:
1404                         case -NFS4ERR_RECLAIM_BAD:
1405                         case -NFS4ERR_RECLAIM_CONFLICT:
1406                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1407                                 status = 0;
1408                 }
1409                 spin_lock(&inode->i_lock);
1410         }
1411         spin_unlock(&inode->i_lock);
1412 out:
1413         up_write(&nfsi->rwsem);
1414         return status;
1415 }
1416
1417 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1418 {
1419         struct nfs4_state *state;
1420         struct nfs4_lock_state *lock;
1421         int status = 0;
1422
1423         /* Note: we rely on the sp->so_states list being ordered
1424          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1425          * states first.
1426          * This is needed to ensure that the server won't give us any
1427          * read delegations that we have to return if, say, we are
1428          * recovering after a network partition or a reboot from a
1429          * server that doesn't support a grace period.
1430          */
1431         spin_lock(&sp->so_lock);
1432         raw_write_seqcount_begin(&sp->so_reclaim_seqcount);
1433 restart:
1434         list_for_each_entry(state, &sp->so_states, open_states) {
1435                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1436                         continue;
1437                 if (!nfs4_valid_open_stateid(state))
1438                         continue;
1439                 if (state->state == 0)
1440                         continue;
1441                 atomic_inc(&state->count);
1442                 spin_unlock(&sp->so_lock);
1443                 status = ops->recover_open(sp, state);
1444                 if (status >= 0) {
1445                         status = nfs4_reclaim_locks(state, ops);
1446                         if (status >= 0) {
1447                                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) {
1448                                         spin_lock(&state->state_lock);
1449                                         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1450                                                 if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
1451                                                         pr_warn_ratelimited("NFS: "
1452                                                                             "%s: Lock reclaim "
1453                                                                             "failed!\n", __func__);
1454                                         }
1455                                         spin_unlock(&state->state_lock);
1456                                 }
1457                                 nfs4_put_open_state(state);
1458                                 spin_lock(&sp->so_lock);
1459                                 goto restart;
1460                         }
1461                 }
1462                 switch (status) {
1463                         default:
1464                                 printk(KERN_ERR "NFS: %s: unhandled error %d\n",
1465                                         __func__, status);
1466                         case -ENOENT:
1467                         case -ENOMEM:
1468                         case -ESTALE:
1469                                 /* Open state on this file cannot be recovered */
1470                                 nfs4_state_mark_recovery_failed(state, status);
1471                                 break;
1472                         case -EAGAIN:
1473                                 ssleep(1);
1474                         case -NFS4ERR_ADMIN_REVOKED:
1475                         case -NFS4ERR_STALE_STATEID:
1476                         case -NFS4ERR_BAD_STATEID:
1477                         case -NFS4ERR_RECLAIM_BAD:
1478                         case -NFS4ERR_RECLAIM_CONFLICT:
1479                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1480                                 break;
1481                         case -NFS4ERR_EXPIRED:
1482                         case -NFS4ERR_NO_GRACE:
1483                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1484                         case -NFS4ERR_STALE_CLIENTID:
1485                         case -NFS4ERR_BADSESSION:
1486                         case -NFS4ERR_BADSLOT:
1487                         case -NFS4ERR_BAD_HIGH_SLOT:
1488                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1489                                 goto out_err;
1490                 }
1491                 nfs4_put_open_state(state);
1492                 spin_lock(&sp->so_lock);
1493                 goto restart;
1494         }
1495         raw_write_seqcount_end(&sp->so_reclaim_seqcount);
1496         spin_unlock(&sp->so_lock);
1497         return 0;
1498 out_err:
1499         nfs4_put_open_state(state);
1500         spin_lock(&sp->so_lock);
1501         raw_write_seqcount_end(&sp->so_reclaim_seqcount);
1502         spin_unlock(&sp->so_lock);
1503         return status;
1504 }
1505
1506 static void nfs4_clear_open_state(struct nfs4_state *state)
1507 {
1508         struct nfs4_lock_state *lock;
1509
1510         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1511         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1512         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1513         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1514         spin_lock(&state->state_lock);
1515         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1516                 lock->ls_seqid.flags = 0;
1517                 clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags);
1518         }
1519         spin_unlock(&state->state_lock);
1520 }
1521
1522 static void nfs4_reset_seqids(struct nfs_server *server,
1523         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1524 {
1525         struct nfs_client *clp = server->nfs_client;
1526         struct nfs4_state_owner *sp;
1527         struct rb_node *pos;
1528         struct nfs4_state *state;
1529
1530         spin_lock(&clp->cl_lock);
1531         for (pos = rb_first(&server->state_owners);
1532              pos != NULL;
1533              pos = rb_next(pos)) {
1534                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1535                 sp->so_seqid.flags = 0;
1536                 spin_lock(&sp->so_lock);
1537                 list_for_each_entry(state, &sp->so_states, open_states) {
1538                         if (mark_reclaim(clp, state))
1539                                 nfs4_clear_open_state(state);
1540                 }
1541                 spin_unlock(&sp->so_lock);
1542         }
1543         spin_unlock(&clp->cl_lock);
1544 }
1545
1546 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1547         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1548 {
1549         struct nfs_server *server;
1550
1551         rcu_read_lock();
1552         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1553                 nfs4_reset_seqids(server, mark_reclaim);
1554         rcu_read_unlock();
1555 }
1556
1557 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1558 {
1559         /* Mark all delegations for reclaim */
1560         nfs_delegation_mark_reclaim(clp);
1561         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1562 }
1563
1564 static void nfs4_reclaim_complete(struct nfs_client *clp,
1565                                  const struct nfs4_state_recovery_ops *ops,
1566                                  struct rpc_cred *cred)
1567 {
1568         /* Notify the server we're done reclaiming our state */
1569         if (ops->reclaim_complete)
1570                 (void)ops->reclaim_complete(clp, cred);
1571 }
1572
1573 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1574 {
1575         struct nfs_client *clp = server->nfs_client;
1576         struct nfs4_state_owner *sp;
1577         struct rb_node *pos;
1578         struct nfs4_state *state;
1579
1580         spin_lock(&clp->cl_lock);
1581         for (pos = rb_first(&server->state_owners);
1582              pos != NULL;
1583              pos = rb_next(pos)) {
1584                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1585                 spin_lock(&sp->so_lock);
1586                 list_for_each_entry(state, &sp->so_states, open_states) {
1587                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1588                                                 &state->flags))
1589                                 continue;
1590                         nfs4_state_mark_reclaim_nograce(clp, state);
1591                 }
1592                 spin_unlock(&sp->so_lock);
1593         }
1594         spin_unlock(&clp->cl_lock);
1595 }
1596
1597 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1598 {
1599         struct nfs_server *server;
1600
1601         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1602                 return 0;
1603
1604         rcu_read_lock();
1605         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1606                 nfs4_clear_reclaim_server(server);
1607         rcu_read_unlock();
1608
1609         nfs_delegation_reap_unclaimed(clp);
1610         return 1;
1611 }
1612
1613 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1614 {
1615         const struct nfs4_state_recovery_ops *ops;
1616         struct rpc_cred *cred;
1617
1618         if (!nfs4_state_clear_reclaim_reboot(clp))
1619                 return;
1620         ops = clp->cl_mvops->reboot_recovery_ops;
1621         cred = nfs4_get_clid_cred(clp);
1622         nfs4_reclaim_complete(clp, ops, cred);
1623         put_rpccred(cred);
1624 }
1625
1626 static void nfs_delegation_clear_all(struct nfs_client *clp)
1627 {
1628         nfs_delegation_mark_reclaim(clp);
1629         nfs_delegation_reap_unclaimed(clp);
1630 }
1631
1632 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1633 {
1634         nfs_delegation_clear_all(clp);
1635         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1636 }
1637
1638 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1639 {
1640         switch (error) {
1641                 case 0:
1642                         break;
1643                 case -NFS4ERR_CB_PATH_DOWN:
1644                         nfs40_handle_cb_pathdown(clp);
1645                         break;
1646                 case -NFS4ERR_NO_GRACE:
1647                         nfs4_state_end_reclaim_reboot(clp);
1648                         break;
1649                 case -NFS4ERR_STALE_CLIENTID:
1650                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1651                         nfs4_state_clear_reclaim_reboot(clp);
1652                         nfs4_state_start_reclaim_reboot(clp);
1653                         break;
1654                 case -NFS4ERR_EXPIRED:
1655                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1656                         nfs4_state_start_reclaim_nograce(clp);
1657                         break;
1658                 case -NFS4ERR_BADSESSION:
1659                 case -NFS4ERR_BADSLOT:
1660                 case -NFS4ERR_BAD_HIGH_SLOT:
1661                 case -NFS4ERR_DEADSESSION:
1662                 case -NFS4ERR_SEQ_FALSE_RETRY:
1663                 case -NFS4ERR_SEQ_MISORDERED:
1664                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1665                         /* Zero session reset errors */
1666                         break;
1667                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1668                         set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1669                         break;
1670                 default:
1671                         dprintk("%s: failed to handle error %d for server %s\n",
1672                                         __func__, error, clp->cl_hostname);
1673                         return error;
1674         }
1675         dprintk("%s: handled error %d for server %s\n", __func__, error,
1676                         clp->cl_hostname);
1677         return 0;
1678 }
1679
1680 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1681 {
1682         struct nfs4_state_owner *sp;
1683         struct nfs_server *server;
1684         struct rb_node *pos;
1685         int status = 0;
1686
1687 restart:
1688         rcu_read_lock();
1689         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1690                 nfs4_purge_state_owners(server);
1691                 spin_lock(&clp->cl_lock);
1692                 for (pos = rb_first(&server->state_owners);
1693                      pos != NULL;
1694                      pos = rb_next(pos)) {
1695                         sp = rb_entry(pos,
1696                                 struct nfs4_state_owner, so_server_node);
1697                         if (!test_and_clear_bit(ops->owner_flag_bit,
1698                                                         &sp->so_flags))
1699                                 continue;
1700                         atomic_inc(&sp->so_count);
1701                         spin_unlock(&clp->cl_lock);
1702                         rcu_read_unlock();
1703
1704                         status = nfs4_reclaim_open_state(sp, ops);
1705                         if (status < 0) {
1706                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1707                                 nfs4_put_state_owner(sp);
1708                                 return nfs4_recovery_handle_error(clp, status);
1709                         }
1710
1711                         nfs4_put_state_owner(sp);
1712                         goto restart;
1713                 }
1714                 spin_unlock(&clp->cl_lock);
1715         }
1716         rcu_read_unlock();
1717         return status;
1718 }
1719
1720 static int nfs4_check_lease(struct nfs_client *clp)
1721 {
1722         struct rpc_cred *cred;
1723         const struct nfs4_state_maintenance_ops *ops =
1724                 clp->cl_mvops->state_renewal_ops;
1725         int status;
1726
1727         /* Is the client already known to have an expired lease? */
1728         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1729                 return 0;
1730         spin_lock(&clp->cl_lock);
1731         cred = ops->get_state_renewal_cred_locked(clp);
1732         spin_unlock(&clp->cl_lock);
1733         if (cred == NULL) {
1734                 cred = nfs4_get_clid_cred(clp);
1735                 status = -ENOKEY;
1736                 if (cred == NULL)
1737                         goto out;
1738         }
1739         status = ops->renew_lease(clp, cred);
1740         put_rpccred(cred);
1741         if (status == -ETIMEDOUT) {
1742                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1743                 return 0;
1744         }
1745 out:
1746         return nfs4_recovery_handle_error(clp, status);
1747 }
1748
1749 /* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors
1750  * and for recoverable errors on EXCHANGE_ID for v4.1
1751  */
1752 static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
1753 {
1754         switch (status) {
1755         case -NFS4ERR_SEQ_MISORDERED:
1756                 if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
1757                         return -ESERVERFAULT;
1758                 /* Lease confirmation error: retry after purging the lease */
1759                 ssleep(1);
1760                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1761                 break;
1762         case -NFS4ERR_STALE_CLIENTID:
1763                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1764                 nfs4_state_clear_reclaim_reboot(clp);
1765                 nfs4_state_start_reclaim_reboot(clp);
1766                 break;
1767         case -NFS4ERR_CLID_INUSE:
1768                 pr_err("NFS: Server %s reports our clientid is in use\n",
1769                         clp->cl_hostname);
1770                 nfs_mark_client_ready(clp, -EPERM);
1771                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1772                 return -EPERM;
1773         case -EACCES:
1774         case -NFS4ERR_DELAY:
1775         case -ETIMEDOUT:
1776         case -EAGAIN:
1777                 ssleep(1);
1778                 break;
1779
1780         case -NFS4ERR_MINOR_VERS_MISMATCH:
1781                 if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1782                         nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
1783                 dprintk("%s: exit with error %d for server %s\n",
1784                                 __func__, -EPROTONOSUPPORT, clp->cl_hostname);
1785                 return -EPROTONOSUPPORT;
1786         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1787                                  * in nfs4_exchange_id */
1788         default:
1789                 dprintk("%s: exit with error %d for server %s\n", __func__,
1790                                 status, clp->cl_hostname);
1791                 return status;
1792         }
1793         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1794         dprintk("%s: handled error %d for server %s\n", __func__, status,
1795                         clp->cl_hostname);
1796         return 0;
1797 }
1798
1799 static int nfs4_establish_lease(struct nfs_client *clp)
1800 {
1801         struct rpc_cred *cred;
1802         const struct nfs4_state_recovery_ops *ops =
1803                 clp->cl_mvops->reboot_recovery_ops;
1804         int status;
1805
1806         cred = nfs4_get_clid_cred(clp);
1807         if (cred == NULL)
1808                 return -ENOENT;
1809         status = ops->establish_clid(clp, cred);
1810         put_rpccred(cred);
1811         if (status != 0)
1812                 return status;
1813         pnfs_destroy_all_layouts(clp);
1814         return 0;
1815 }
1816
1817 /*
1818  * Returns zero or a negative errno.  NFS4ERR values are converted
1819  * to local errno values.
1820  */
1821 static int nfs4_reclaim_lease(struct nfs_client *clp)
1822 {
1823         int status;
1824
1825         status = nfs4_establish_lease(clp);
1826         if (status < 0)
1827                 return nfs4_handle_reclaim_lease_error(clp, status);
1828         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state))
1829                 nfs4_state_start_reclaim_nograce(clp);
1830         if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1831                 set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1832         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1833         clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1834         return 0;
1835 }
1836
1837 static int nfs4_purge_lease(struct nfs_client *clp)
1838 {
1839         int status;
1840
1841         status = nfs4_establish_lease(clp);
1842         if (status < 0)
1843                 return nfs4_handle_reclaim_lease_error(clp, status);
1844         clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1845         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1846         nfs4_state_start_reclaim_nograce(clp);
1847         return 0;
1848 }
1849
1850 /*
1851  * Try remote migration of one FSID from a source server to a
1852  * destination server.  The source server provides a list of
1853  * potential destinations.
1854  *
1855  * Returns zero or a negative NFS4ERR status code.
1856  */
1857 static int nfs4_try_migration(struct nfs_server *server, struct rpc_cred *cred)
1858 {
1859         struct nfs_client *clp = server->nfs_client;
1860         struct nfs4_fs_locations *locations = NULL;
1861         struct inode *inode;
1862         struct page *page;
1863         int status, result;
1864
1865         dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__,
1866                         (unsigned long long)server->fsid.major,
1867                         (unsigned long long)server->fsid.minor,
1868                         clp->cl_hostname);
1869
1870         result = 0;
1871         page = alloc_page(GFP_KERNEL);
1872         locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
1873         if (page == NULL || locations == NULL) {
1874                 dprintk("<-- %s: no memory\n", __func__);
1875                 goto out;
1876         }
1877
1878         inode = server->super->s_root->d_inode;
1879         result = nfs4_proc_get_locations(inode, locations, page, cred);
1880         if (result) {
1881                 dprintk("<-- %s: failed to retrieve fs_locations: %d\n",
1882                         __func__, result);
1883                 goto out;
1884         }
1885
1886         result = -NFS4ERR_NXIO;
1887         if (!(locations->fattr.valid & NFS_ATTR_FATTR_V4_LOCATIONS)) {
1888                 dprintk("<-- %s: No fs_locations data, migration skipped\n",
1889                         __func__);
1890                 goto out;
1891         }
1892
1893         nfs4_begin_drain_session(clp);
1894
1895         status = nfs4_replace_transport(server, locations);
1896         if (status != 0) {
1897                 dprintk("<-- %s: failed to replace transport: %d\n",
1898                         __func__, status);
1899                 goto out;
1900         }
1901
1902         result = 0;
1903         dprintk("<-- %s: migration succeeded\n", __func__);
1904
1905 out:
1906         if (page != NULL)
1907                 __free_page(page);
1908         kfree(locations);
1909         if (result) {
1910                 pr_err("NFS: migration recovery failed (server %s)\n",
1911                                 clp->cl_hostname);
1912                 set_bit(NFS_MIG_FAILED, &server->mig_status);
1913         }
1914         return result;
1915 }
1916
1917 /*
1918  * Returns zero or a negative NFS4ERR status code.
1919  */
1920 static int nfs4_handle_migration(struct nfs_client *clp)
1921 {
1922         const struct nfs4_state_maintenance_ops *ops =
1923                                 clp->cl_mvops->state_renewal_ops;
1924         struct nfs_server *server;
1925         struct rpc_cred *cred;
1926
1927         dprintk("%s: migration reported on \"%s\"\n", __func__,
1928                         clp->cl_hostname);
1929
1930         spin_lock(&clp->cl_lock);
1931         cred = ops->get_state_renewal_cred_locked(clp);
1932         spin_unlock(&clp->cl_lock);
1933         if (cred == NULL)
1934                 return -NFS4ERR_NOENT;
1935
1936         clp->cl_mig_gen++;
1937 restart:
1938         rcu_read_lock();
1939         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1940                 int status;
1941
1942                 if (server->mig_gen == clp->cl_mig_gen)
1943                         continue;
1944                 server->mig_gen = clp->cl_mig_gen;
1945
1946                 if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION,
1947                                                 &server->mig_status))
1948                         continue;
1949
1950                 rcu_read_unlock();
1951                 status = nfs4_try_migration(server, cred);
1952                 if (status < 0) {
1953                         put_rpccred(cred);
1954                         return status;
1955                 }
1956                 goto restart;
1957         }
1958         rcu_read_unlock();
1959         put_rpccred(cred);
1960         return 0;
1961 }
1962
1963 /*
1964  * Test each nfs_server on the clp's cl_superblocks list to see
1965  * if it's moved to another server.  Stop when the server no longer
1966  * returns NFS4ERR_LEASE_MOVED.
1967  */
1968 static int nfs4_handle_lease_moved(struct nfs_client *clp)
1969 {
1970         const struct nfs4_state_maintenance_ops *ops =
1971                                 clp->cl_mvops->state_renewal_ops;
1972         struct nfs_server *server;
1973         struct rpc_cred *cred;
1974
1975         dprintk("%s: lease moved reported on \"%s\"\n", __func__,
1976                         clp->cl_hostname);
1977
1978         spin_lock(&clp->cl_lock);
1979         cred = ops->get_state_renewal_cred_locked(clp);
1980         spin_unlock(&clp->cl_lock);
1981         if (cred == NULL)
1982                 return -NFS4ERR_NOENT;
1983
1984         clp->cl_mig_gen++;
1985 restart:
1986         rcu_read_lock();
1987         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1988                 struct inode *inode;
1989                 int status;
1990
1991                 if (server->mig_gen == clp->cl_mig_gen)
1992                         continue;
1993                 server->mig_gen = clp->cl_mig_gen;
1994
1995                 rcu_read_unlock();
1996
1997                 inode = server->super->s_root->d_inode;
1998                 status = nfs4_proc_fsid_present(inode, cred);
1999                 if (status != -NFS4ERR_MOVED)
2000                         goto restart;   /* wasn't this one */
2001                 if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED)
2002                         goto restart;   /* there are more */
2003                 goto out;
2004         }
2005         rcu_read_unlock();
2006
2007 out:
2008         put_rpccred(cred);
2009         return 0;
2010 }
2011
2012 /**
2013  * nfs4_discover_server_trunking - Detect server IP address trunking
2014  *
2015  * @clp: nfs_client under test
2016  * @result: OUT: found nfs_client, or clp
2017  *
2018  * Returns zero or a negative errno.  If zero is returned,
2019  * an nfs_client pointer is planted in "result".
2020  *
2021  * Note: since we are invoked in process context, and
2022  * not from inside the state manager, we cannot use
2023  * nfs4_handle_reclaim_lease_error().
2024  */
2025 int nfs4_discover_server_trunking(struct nfs_client *clp,
2026                                   struct nfs_client **result)
2027 {
2028         const struct nfs4_state_recovery_ops *ops =
2029                                 clp->cl_mvops->reboot_recovery_ops;
2030         struct rpc_clnt *clnt;
2031         struct rpc_cred *cred;
2032         int i, status;
2033
2034         dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
2035
2036         clnt = clp->cl_rpcclient;
2037         i = 0;
2038
2039         mutex_lock(&nfs_clid_init_mutex);
2040 again:
2041         status  = -ENOENT;
2042         cred = nfs4_get_clid_cred(clp);
2043         if (cred == NULL)
2044                 goto out_unlock;
2045
2046         status = ops->detect_trunking(clp, result, cred);
2047         put_rpccred(cred);
2048         switch (status) {
2049         case 0:
2050                 break;
2051         case -ETIMEDOUT:
2052                 if (clnt->cl_softrtry)
2053                         break;
2054         case -NFS4ERR_DELAY:
2055         case -EAGAIN:
2056                 ssleep(1);
2057         case -NFS4ERR_STALE_CLIENTID:
2058                 dprintk("NFS: %s after status %d, retrying\n",
2059                         __func__, status);
2060                 goto again;
2061         case -EACCES:
2062                 if (i++ == 0) {
2063                         nfs4_root_machine_cred(clp);
2064                         goto again;
2065                 }
2066                 if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX)
2067                         break;
2068         case -NFS4ERR_CLID_INUSE:
2069         case -NFS4ERR_WRONGSEC:
2070                 /* No point in retrying if we already used RPC_AUTH_UNIX */
2071                 if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) {
2072                         status = -EPERM;
2073                         break;
2074                 }
2075                 clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
2076                 if (IS_ERR(clnt)) {
2077                         status = PTR_ERR(clnt);
2078                         break;
2079                 }
2080                 /* Note: this is safe because we haven't yet marked the
2081                  * client as ready, so we are the only user of
2082                  * clp->cl_rpcclient
2083                  */
2084                 clnt = xchg(&clp->cl_rpcclient, clnt);
2085                 rpc_shutdown_client(clnt);
2086                 clnt = clp->cl_rpcclient;
2087                 goto again;
2088
2089         case -NFS4ERR_MINOR_VERS_MISMATCH:
2090                 status = -EPROTONOSUPPORT;
2091                 break;
2092
2093         case -EKEYEXPIRED:
2094         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
2095                                  * in nfs4_exchange_id */
2096                 status = -EKEYEXPIRED;
2097                 break;
2098         default:
2099                 pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
2100                                 __func__, status);
2101                 status = -EIO;
2102         }
2103
2104 out_unlock:
2105         mutex_unlock(&nfs_clid_init_mutex);
2106         dprintk("NFS: %s: status = %d\n", __func__, status);
2107         return status;
2108 }
2109
2110 #ifdef CONFIG_NFS_V4_1
2111 void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
2112 {
2113         struct nfs_client *clp = session->clp;
2114
2115         switch (err) {
2116         default:
2117                 set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2118                 break;
2119         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
2120                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2121         }
2122         nfs4_schedule_lease_recovery(clp);
2123 }
2124 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
2125
2126 static void nfs41_ping_server(struct nfs_client *clp)
2127 {
2128         /* Use CHECK_LEASE to ping the server with a SEQUENCE */
2129         set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
2130         nfs4_schedule_state_manager(clp);
2131 }
2132
2133 void nfs41_server_notify_target_slotid_update(struct nfs_client *clp)
2134 {
2135         nfs41_ping_server(clp);
2136 }
2137
2138 void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp)
2139 {
2140         nfs41_ping_server(clp);
2141 }
2142
2143 static void nfs4_reset_all_state(struct nfs_client *clp)
2144 {
2145         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
2146                 set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
2147                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
2148                 nfs4_state_start_reclaim_nograce(clp);
2149                 dprintk("%s: scheduling reset of all state for server %s!\n",
2150                                 __func__, clp->cl_hostname);
2151                 nfs4_schedule_state_manager(clp);
2152         }
2153 }
2154
2155 static void nfs41_handle_server_reboot(struct nfs_client *clp)
2156 {
2157         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
2158                 nfs4_state_start_reclaim_reboot(clp);
2159                 dprintk("%s: server %s rebooted!\n", __func__,
2160                                 clp->cl_hostname);
2161                 nfs4_schedule_state_manager(clp);
2162         }
2163 }
2164
2165 static void nfs41_handle_state_revoked(struct nfs_client *clp)
2166 {
2167         nfs4_reset_all_state(clp);
2168         dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
2169 }
2170
2171 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
2172 {
2173         /* This will need to handle layouts too */
2174         nfs_expire_all_delegations(clp);
2175         dprintk("%s: Recallable state revoked on server %s!\n", __func__,
2176                         clp->cl_hostname);
2177 }
2178
2179 static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
2180 {
2181         nfs_expire_all_delegations(clp);
2182         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
2183                 nfs4_schedule_state_manager(clp);
2184         dprintk("%s: server %s declared a backchannel fault\n", __func__,
2185                         clp->cl_hostname);
2186 }
2187
2188 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
2189 {
2190         if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2191                 &clp->cl_state) == 0)
2192                 nfs4_schedule_state_manager(clp);
2193 }
2194
2195 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
2196 {
2197         if (!flags)
2198                 return;
2199
2200         dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
2201                 __func__, clp->cl_hostname, clp->cl_clientid, flags);
2202
2203         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
2204                 nfs41_handle_server_reboot(clp);
2205         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
2206                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
2207                             SEQ4_STATUS_ADMIN_STATE_REVOKED))
2208                 nfs41_handle_state_revoked(clp);
2209         if (flags & SEQ4_STATUS_LEASE_MOVED)
2210                 nfs4_schedule_lease_moved_recovery(clp);
2211         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
2212                 nfs41_handle_recallable_state_revoked(clp);
2213         if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
2214                 nfs41_handle_backchannel_fault(clp);
2215         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
2216                                 SEQ4_STATUS_CB_PATH_DOWN_SESSION))
2217                 nfs41_handle_cb_path_down(clp);
2218 }
2219
2220 static int nfs4_reset_session(struct nfs_client *clp)
2221 {
2222         struct rpc_cred *cred;
2223         int status;
2224
2225         if (!nfs4_has_session(clp))
2226                 return 0;
2227         nfs4_begin_drain_session(clp);
2228         cred = nfs4_get_clid_cred(clp);
2229         status = nfs4_proc_destroy_session(clp->cl_session, cred);
2230         switch (status) {
2231         case 0:
2232         case -NFS4ERR_BADSESSION:
2233         case -NFS4ERR_DEADSESSION:
2234                 break;
2235         case -NFS4ERR_BACK_CHAN_BUSY:
2236         case -NFS4ERR_DELAY:
2237                 set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2238                 status = 0;
2239                 ssleep(1);
2240                 goto out;
2241         default:
2242                 status = nfs4_recovery_handle_error(clp, status);
2243                 goto out;
2244         }
2245
2246         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
2247         status = nfs4_proc_create_session(clp, cred);
2248         if (status) {
2249                 dprintk("%s: session reset failed with status %d for server %s!\n",
2250                         __func__, status, clp->cl_hostname);
2251                 status = nfs4_handle_reclaim_lease_error(clp, status);
2252                 goto out;
2253         }
2254         nfs41_finish_session_reset(clp);
2255         dprintk("%s: session reset was successful for server %s!\n",
2256                         __func__, clp->cl_hostname);
2257 out:
2258         if (cred)
2259                 put_rpccred(cred);
2260         return status;
2261 }
2262
2263 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2264 {
2265         struct rpc_cred *cred;
2266         int ret;
2267
2268         if (!nfs4_has_session(clp))
2269                 return 0;
2270         nfs4_begin_drain_session(clp);
2271         cred = nfs4_get_clid_cred(clp);
2272         ret = nfs4_proc_bind_conn_to_session(clp, cred);
2273         if (cred)
2274                 put_rpccred(cred);
2275         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2276         switch (ret) {
2277         case 0:
2278                 dprintk("%s: bind_conn_to_session was successful for server %s!\n",
2279                         __func__, clp->cl_hostname);
2280                 break;
2281         case -NFS4ERR_DELAY:
2282                 ssleep(1);
2283                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2284                 break;
2285         default:
2286                 return nfs4_recovery_handle_error(clp, ret);
2287         }
2288         return 0;
2289 }
2290 #else /* CONFIG_NFS_V4_1 */
2291 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
2292
2293 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2294 {
2295         return 0;
2296 }
2297 #endif /* CONFIG_NFS_V4_1 */
2298
2299 static void nfs4_state_manager(struct nfs_client *clp)
2300 {
2301         int status = 0;
2302         const char *section = "", *section_sep = "";
2303
2304         /* Ensure exclusive access to NFSv4 state */
2305         do {
2306                 if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
2307                         section = "purge state";
2308                         status = nfs4_purge_lease(clp);
2309                         if (status < 0)
2310                                 goto out_error;
2311                         continue;
2312                 }
2313
2314                 if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
2315                         section = "lease expired";
2316                         /* We're going to have to re-establish a clientid */
2317                         status = nfs4_reclaim_lease(clp);
2318                         if (status < 0)
2319                                 goto out_error;
2320                         continue;
2321                 }
2322
2323                 /* Initialize or reset the session */
2324                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) {
2325                         section = "reset session";
2326                         status = nfs4_reset_session(clp);
2327                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
2328                                 continue;
2329                         if (status < 0)
2330                                 goto out_error;
2331                 }
2332
2333                 /* Send BIND_CONN_TO_SESSION */
2334                 if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2335                                 &clp->cl_state)) {
2336                         section = "bind conn to session";
2337                         status = nfs4_bind_conn_to_session(clp);
2338                         if (status < 0)
2339                                 goto out_error;
2340                         continue;
2341                 }
2342
2343                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
2344                         section = "check lease";
2345                         status = nfs4_check_lease(clp);
2346                         if (status < 0)
2347                                 goto out_error;
2348                 }
2349
2350                 if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) {
2351                         section = "migration";
2352                         status = nfs4_handle_migration(clp);
2353                         if (status < 0)
2354                                 goto out_error;
2355                 }
2356
2357                 if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) {
2358                         section = "lease moved";
2359                         status = nfs4_handle_lease_moved(clp);
2360                         if (status < 0)
2361                                 goto out_error;
2362                 }
2363
2364                 /* First recover reboot state... */
2365                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
2366                         section = "reclaim reboot";
2367                         status = nfs4_do_reclaim(clp,
2368                                 clp->cl_mvops->reboot_recovery_ops);
2369                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
2370                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
2371                                 continue;
2372                         nfs4_state_end_reclaim_reboot(clp);
2373                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
2374                                 continue;
2375                         if (status < 0)
2376                                 goto out_error;
2377                 }
2378
2379                 /* Now recover expired state... */
2380                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
2381                         section = "reclaim nograce";
2382                         status = nfs4_do_reclaim(clp,
2383                                 clp->cl_mvops->nograce_recovery_ops);
2384                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
2385                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
2386                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
2387                                 continue;
2388                         if (status < 0)
2389                                 goto out_error;
2390                 }
2391
2392                 nfs4_end_drain_session(clp);
2393                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
2394                         nfs_client_return_marked_delegations(clp);
2395                         continue;
2396                 }
2397
2398                 nfs4_clear_state_manager_bit(clp);
2399                 /* Did we race with an attempt to give us more work? */
2400                 if (clp->cl_state == 0)
2401                         break;
2402                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
2403                         break;
2404         } while (atomic_read(&clp->cl_count) > 1);
2405         return;
2406 out_error:
2407         if (strlen(section))
2408                 section_sep = ": ";
2409         pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s"
2410                         " with error %d\n", section_sep, section,
2411                         clp->cl_hostname, -status);
2412         ssleep(1);
2413         nfs4_end_drain_session(clp);
2414         nfs4_clear_state_manager_bit(clp);
2415 }
2416
2417 static int nfs4_run_state_manager(void *ptr)
2418 {
2419         struct nfs_client *clp = ptr;
2420
2421         allow_signal(SIGKILL);
2422         nfs4_state_manager(clp);
2423         nfs_put_client(clp);
2424         module_put_and_exit(0);
2425         return 0;
2426 }
2427
2428 /*
2429  * Local variables:
2430  *  c-basic-offset: 8
2431  * End:
2432  */