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 static LIST_HEAD(nfs4_clientid_list);
  71
  72 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
  73 {
  74         struct nfs4_setclientid_res clid = {
  75                 .clientid = clp->cl_clientid,
  76                 .confirm = clp->cl_confirm,
  77         };
  78         unsigned short port;
  79         int status;
  80         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  81
  82         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
  83                 goto do_confirm;
  84         port = nn->nfs_callback_tcpport;
  85         if (clp->cl_addr.ss_family == AF_INET6)
  86                 port = nn->nfs_callback_tcpport6;
  87
  88         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
  89         if (status != 0)
  90                 goto out;
  91         clp->cl_clientid = clid.clientid;
  92         clp->cl_confirm = clid.confirm;
  93         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  94 do_confirm:
  95         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
  96         if (status != 0)
  97                 goto out;
  98         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
  99         nfs4_schedule_state_renewal(clp);
 100 out:
 101         return status;
 102 }
 103
 104 /**
 105  * nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
 106  *
 107  * @clp: nfs_client under test
 108  * @result: OUT: found nfs_client, or clp
 109  * @cred: credential to use for trunking test
 110  *
 111  * Returns zero, a negative errno, or a negative NFS4ERR status.
 112  * If zero is returned, an nfs_client pointer is planted in
 113  * "result".
 114  *
 115  * Note: The returned client may not yet be marked ready.
 116  */
 117 int nfs40_discover_server_trunking(struct nfs_client *clp,
 118                                    struct nfs_client **result,
 119                                    struct rpc_cred *cred)
 120 {
 121         struct nfs4_setclientid_res clid = {
 122                 .clientid = clp->cl_clientid,
 123                 .confirm = clp->cl_confirm,
 124         };
 125         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
 126         unsigned short port;
 127         int status;
 128
 129         port = nn->nfs_callback_tcpport;
 130         if (clp->cl_addr.ss_family == AF_INET6)
 131                 port = nn->nfs_callback_tcpport6;
 132
 133         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
 134         if (status != 0)
 135                 goto out;
 136         clp->cl_clientid = clid.clientid;
 137         clp->cl_confirm = clid.confirm;
 138
 139         status = nfs40_walk_client_list(clp, result, cred);
 140         switch (status) {
 141         case -NFS4ERR_STALE_CLIENTID:
 142                 set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 143         case 0:
 144                 /* Sustain the lease, even if it's empty.  If the clientid4
 145                  * goes stale it's of no use for trunking discovery. */
 146                 nfs4_schedule_state_renewal(*result);
 147                 break;
 148         }
 149
 150 out:
 151         return status;
 152 }
 153
 154 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
 155 {
 156         struct rpc_cred *cred = NULL;
 157
 158         if (clp->cl_machine_cred != NULL)
 159                 cred = get_rpccred(clp->cl_machine_cred);
 160         return cred;
 161 }
 162
 163 static void nfs4_clear_machine_cred(struct nfs_client *clp)
 164 {
 165         struct rpc_cred *cred;
 166
 167         spin_lock(&clp->cl_lock);
 168         cred = clp->cl_machine_cred;
 169         clp->cl_machine_cred = NULL;
 170         spin_unlock(&clp->cl_lock);
 171         if (cred != NULL)
 172                 put_rpccred(cred);
 173 }
 174
 175 static struct rpc_cred *
 176 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 177 {
 178         struct rpc_cred *cred = NULL;
 179         struct nfs4_state_owner *sp;
 180         struct rb_node *pos;
 181
 182         for (pos = rb_first(&server->state_owners);
 183              pos != NULL;
 184              pos = rb_next(pos)) {
 185                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 186                 if (list_empty(&sp->so_states))
 187                         continue;
 188                 cred = get_rpccred(sp->so_cred);
 189                 break;
 190         }
 191         return cred;
 192 }
 193
 194 /**
 195  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
 196  * @clp: client state handle
 197  *
 198  * Returns an rpc_cred with reference count bumped, or NULL.
 199  * Caller must hold clp->cl_lock.
 200  */
 201 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 202 {
 203         struct rpc_cred *cred = NULL;
 204         struct nfs_server *server;
 205
 206         /* Use machine credentials if available */
 207         cred = nfs4_get_machine_cred_locked(clp);
 208         if (cred != NULL)
 209                 goto out;
 210
 211         rcu_read_lock();
 212         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 213                 cred = nfs4_get_renew_cred_server_locked(server);
 214                 if (cred != NULL)
 215                         break;
 216         }
 217         rcu_read_unlock();
 218
 219 out:
 220         return cred;
 221 }
 222
 223 #if defined(CONFIG_NFS_V4_1)
 224
 225 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 226 {
 227         int status;
 228         struct nfs_fsinfo fsinfo;
 229
 230         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
 231                 nfs4_schedule_state_renewal(clp);
 232                 return 0;
 233         }
 234
 235         status = nfs4_proc_get_lease_time(clp, &fsinfo);
 236         if (status == 0) {
 237                 /* Update lease time and schedule renewal */
 238                 spin_lock(&clp->cl_lock);
 239                 clp->cl_lease_time = fsinfo.lease_time * HZ;
 240                 clp->cl_last_renewal = jiffies;
 241                 spin_unlock(&clp->cl_lock);
 242
 243                 nfs4_schedule_state_renewal(clp);
 244         }
 245
 246         return status;
 247 }
 248
 249 /*
 250  * Back channel returns NFS4ERR_DELAY for new requests when
 251  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
 252  * is ended.
 253  */
 254 static void nfs4_end_drain_session(struct nfs_client *clp)
 255 {
 256         struct nfs4_session *ses = clp->cl_session;
 257         struct nfs4_slot_table *tbl;
 258         unsigned int i;
 259
 260         if (ses == NULL)
 261                 return;
 262         tbl = &ses->fc_slot_table;
 263         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
 264                 spin_lock(&tbl->slot_tbl_lock);
 265                 for (i = 0; i <= tbl->max_slotid; i++) {
 266                         if (rpc_wake_up_first(&tbl->slot_tbl_waitq,
 267                                                 nfs4_set_task_privileged,
 268                                                 NULL) == NULL)
 269                                 break;
 270                 }
 271                 spin_unlock(&tbl->slot_tbl_lock);
 272         }
 273 }
 274
 275 /*
 276  * Signal state manager thread if session fore channel is drained
 277  */
 278 void nfs4_session_drain_complete(struct nfs4_session *session,
 279                 struct nfs4_slot_table *tbl)
 280 {
 281         if (nfs4_session_draining(session))
 282                 complete(&tbl->complete);
 283 }
 284
 285 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
 286 {
 287         spin_lock(&tbl->slot_tbl_lock);
 288         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
 289                 INIT_COMPLETION(tbl->complete);
 290                 spin_unlock(&tbl->slot_tbl_lock);
 291                 return wait_for_completion_interruptible(&tbl->complete);
 292         }
 293         spin_unlock(&tbl->slot_tbl_lock);
 294         return 0;
 295 }
 296
 297 static int nfs4_begin_drain_session(struct nfs_client *clp)
 298 {
 299         struct nfs4_session *ses = clp->cl_session;
 300         int ret = 0;
 301
 302         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
 303         /* back channel */
 304         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
 305         if (ret)
 306                 return ret;
 307         /* fore channel */
 308         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
 309 }
 310
 311 static void nfs41_finish_session_reset(struct nfs_client *clp)
 312 {
 313         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 314         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
 315         /* create_session negotiated new slot table */
 316         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
 317         nfs41_setup_state_renewal(clp);
 318 }
 319
 320 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
 321 {
 322         int status;
 323
 324         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
 325                 goto do_confirm;
 326         nfs4_begin_drain_session(clp);
 327         status = nfs4_proc_exchange_id(clp, cred);
 328         if (status != 0)
 329                 goto out;
 330         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 331 do_confirm:
 332         status = nfs4_proc_create_session(clp, cred);
 333         if (status != 0)
 334                 goto out;
 335         nfs41_finish_session_reset(clp);
 336         nfs_mark_client_ready(clp, NFS_CS_READY);
 337 out:
 338         return status;
 339 }
 340
 341 /**
 342  * nfs41_discover_server_trunking - Detect server IP address trunking (mv1)
 343  *
 344  * @clp: nfs_client under test
 345  * @result: OUT: found nfs_client, or clp
 346  * @cred: credential to use for trunking test
 347  *
 348  * Returns NFS4_OK, a negative errno, or a negative NFS4ERR status.
 349  * If NFS4_OK is returned, an nfs_client pointer is planted in
 350  * "result".
 351  *
 352  * Note: The returned client may not yet be marked ready.
 353  */
 354 int nfs41_discover_server_trunking(struct nfs_client *clp,
 355                                    struct nfs_client **result,
 356                                    struct rpc_cred *cred)
 357 {
 358         int status;
 359
 360         status = nfs4_proc_exchange_id(clp, cred);
 361         if (status != NFS4_OK)
 362                 return status;
 363         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 364
 365         return nfs41_walk_client_list(clp, result, cred);
 366 }
 367
 368 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 369 {
 370         struct rpc_cred *cred;
 371
 372         spin_lock(&clp->cl_lock);
 373         cred = nfs4_get_machine_cred_locked(clp);
 374         spin_unlock(&clp->cl_lock);
 375         return cred;
 376 }
 377
 378 #endif /* CONFIG_NFS_V4_1 */
 379
 380 static struct rpc_cred *
 381 nfs4_get_setclientid_cred_server(struct nfs_server *server)
 382 {
 383         struct nfs_client *clp = server->nfs_client;
 384         struct rpc_cred *cred = NULL;
 385         struct nfs4_state_owner *sp;
 386         struct rb_node *pos;
 387
 388         spin_lock(&clp->cl_lock);
 389         pos = rb_first(&server->state_owners);
 390         if (pos != NULL) {
 391                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
 392                 cred = get_rpccred(sp->so_cred);
 393         }
 394         spin_unlock(&clp->cl_lock);
 395         return cred;
 396 }
 397
 398 /**
 399  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
 400  * @clp: client state handle
 401  *
 402  * Returns an rpc_cred with reference count bumped, or NULL.
 403  */
 404 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
 405 {
 406         struct nfs_server *server;
 407         struct rpc_cred *cred;
 408
 409         spin_lock(&clp->cl_lock);
 410         cred = nfs4_get_machine_cred_locked(clp);
 411         spin_unlock(&clp->cl_lock);
 412         if (cred != NULL)
 413                 goto out;
 414
 415         rcu_read_lock();
 416         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 417                 cred = nfs4_get_setclientid_cred_server(server);
 418                 if (cred != NULL)
 419                         break;
 420         }
 421         rcu_read_unlock();
 422
 423 out:
 424         return cred;
 425 }
 426
 427 static struct nfs4_state_owner *
 428 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
 429 {
 430         struct rb_node **p = &server->state_owners.rb_node,
 431                        *parent = NULL;
 432         struct nfs4_state_owner *sp;
 433
 434         while (*p != NULL) {
 435                 parent = *p;
 436                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 437
 438                 if (cred < sp->so_cred)
 439                         p = &parent->rb_left;
 440                 else if (cred > sp->so_cred)
 441                         p = &parent->rb_right;
 442                 else {
 443                         if (!list_empty(&sp->so_lru))
 444                                 list_del_init(&sp->so_lru);
 445                         atomic_inc(&sp->so_count);
 446                         return sp;
 447                 }
 448         }
 449         return NULL;
 450 }
 451
 452 static struct nfs4_state_owner *
 453 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
 454 {
 455         struct nfs_server *server = new->so_server;
 456         struct rb_node **p = &server->state_owners.rb_node,
 457                        *parent = NULL;
 458         struct nfs4_state_owner *sp;
 459         int err;
 460
 461         while (*p != NULL) {
 462                 parent = *p;
 463                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
 464
 465                 if (new->so_cred < sp->so_cred)
 466                         p = &parent->rb_left;
 467                 else if (new->so_cred > sp->so_cred)
 468                         p = &parent->rb_right;
 469                 else {
 470                         if (!list_empty(&sp->so_lru))
 471                                 list_del_init(&sp->so_lru);
 472                         atomic_inc(&sp->so_count);
 473                         return sp;
 474                 }
 475         }
 476         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
 477         if (err)
 478                 return ERR_PTR(err);
 479         rb_link_node(&new->so_server_node, parent, p);
 480         rb_insert_color(&new->so_server_node, &server->state_owners);
 481         return new;
 482 }
 483
 484 static void
 485 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
 486 {
 487         struct nfs_server *server = sp->so_server;
 488
 489         if (!RB_EMPTY_NODE(&sp->so_server_node))
 490                 rb_erase(&sp->so_server_node, &server->state_owners);
 491         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
 492 }
 493
 494 static void
 495 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
 496 {
 497         sc->create_time = ktime_get();
 498         sc->flags = 0;
 499         sc->counter = 0;
 500         spin_lock_init(&sc->lock);
 501         INIT_LIST_HEAD(&sc->list);
 502         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
 503 }
 504
 505 static void
 506 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
 507 {
 508         rpc_destroy_wait_queue(&sc->wait);
 509 }
 510
 511 /*
 512  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 513  * create a new state_owner.
 514  *
 515  */
 516 static struct nfs4_state_owner *
 517 nfs4_alloc_state_owner(struct nfs_server *server,
 518                 struct rpc_cred *cred,
 519                 gfp_t gfp_flags)
 520 {
 521         struct nfs4_state_owner *sp;
 522
 523         sp = kzalloc(sizeof(*sp), gfp_flags);
 524         if (!sp)
 525                 return NULL;
 526         sp->so_server = server;
 527         sp->so_cred = get_rpccred(cred);
 528         spin_lock_init(&sp->so_lock);
 529         INIT_LIST_HEAD(&sp->so_states);
 530         nfs4_init_seqid_counter(&sp->so_seqid);
 531         atomic_set(&sp->so_count, 1);
 532         INIT_LIST_HEAD(&sp->so_lru);
 533         return sp;
 534 }
 535
 536 static void
 537 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
 538 {
 539         struct rb_node *rb_node = &sp->so_server_node;
 540
 541         if (!RB_EMPTY_NODE(rb_node)) {
 542                 struct nfs_server *server = sp->so_server;
 543                 struct nfs_client *clp = server->nfs_client;
 544
 545                 spin_lock(&clp->cl_lock);
 546                 if (!RB_EMPTY_NODE(rb_node)) {
 547                         rb_erase(rb_node, &server->state_owners);
 548                         RB_CLEAR_NODE(rb_node);
 549                 }
 550                 spin_unlock(&clp->cl_lock);
 551         }
 552 }
 553
 554 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
 555 {
 556         nfs4_destroy_seqid_counter(&sp->so_seqid);
 557         put_rpccred(sp->so_cred);
 558         kfree(sp);
 559 }
 560
 561 static void nfs4_gc_state_owners(struct nfs_server *server)
 562 {
 563         struct nfs_client *clp = server->nfs_client;
 564         struct nfs4_state_owner *sp, *tmp;
 565         unsigned long time_min, time_max;
 566         LIST_HEAD(doomed);
 567
 568         spin_lock(&clp->cl_lock);
 569         time_max = jiffies;
 570         time_min = (long)time_max - (long)clp->cl_lease_time;
 571         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 572                 /* NB: LRU is sorted so that oldest is at the head */
 573                 if (time_in_range(sp->so_expires, time_min, time_max))
 574                         break;
 575                 list_move(&sp->so_lru, &doomed);
 576                 nfs4_remove_state_owner_locked(sp);
 577         }
 578         spin_unlock(&clp->cl_lock);
 579
 580         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 581                 list_del(&sp->so_lru);
 582                 nfs4_free_state_owner(sp);
 583         }
 584 }
 585
 586 /**
 587  * nfs4_get_state_owner - Look up a state owner given a credential
 588  * @server: nfs_server to search
 589  * @cred: RPC credential to match
 590  *
 591  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
 592  */
 593 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
 594                                               struct rpc_cred *cred,
 595                                               gfp_t gfp_flags)
 596 {
 597         struct nfs_client *clp = server->nfs_client;
 598         struct nfs4_state_owner *sp, *new;
 599
 600         spin_lock(&clp->cl_lock);
 601         sp = nfs4_find_state_owner_locked(server, cred);
 602         spin_unlock(&clp->cl_lock);
 603         if (sp != NULL)
 604                 goto out;
 605         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
 606         if (new == NULL)
 607                 goto out;
 608         do {
 609                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
 610                         break;
 611                 spin_lock(&clp->cl_lock);
 612                 sp = nfs4_insert_state_owner_locked(new);
 613                 spin_unlock(&clp->cl_lock);
 614         } while (sp == ERR_PTR(-EAGAIN));
 615         if (sp != new)
 616                 nfs4_free_state_owner(new);
 617 out:
 618         nfs4_gc_state_owners(server);
 619         return sp;
 620 }
 621
 622 /**
 623  * nfs4_put_state_owner - Release a nfs4_state_owner
 624  * @sp: state owner data to release
 625  *
 626  * Note that we keep released state owners on an LRU
 627  * list.
 628  * This caches valid state owners so that they can be
 629  * reused, to avoid the OPEN_CONFIRM on minor version 0.
 630  * It also pins the uniquifier of dropped state owners for
 631  * a while, to ensure that those state owner names are
 632  * never reused.
 633  */
 634 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 635 {
 636         struct nfs_server *server = sp->so_server;
 637         struct nfs_client *clp = server->nfs_client;
 638
 639         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 640                 return;
 641
 642         sp->so_expires = jiffies;
 643         list_add_tail(&sp->so_lru, &server->state_owners_lru);
 644         spin_unlock(&clp->cl_lock);
 645 }
 646
 647 /**
 648  * nfs4_purge_state_owners - Release all cached state owners
 649  * @server: nfs_server with cached state owners to release
 650  *
 651  * Called at umount time.  Remaining state owners will be on
 652  * the LRU with ref count of zero.
 653  */
 654 void nfs4_purge_state_owners(struct nfs_server *server)
 655 {
 656         struct nfs_client *clp = server->nfs_client;
 657         struct nfs4_state_owner *sp, *tmp;
 658         LIST_HEAD(doomed);
 659
 660         spin_lock(&clp->cl_lock);
 661         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
 662                 list_move(&sp->so_lru, &doomed);
 663                 nfs4_remove_state_owner_locked(sp);
 664         }
 665         spin_unlock(&clp->cl_lock);
 666
 667         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
 668                 list_del(&sp->so_lru);
 669                 nfs4_free_state_owner(sp);
 670         }
 671 }
 672
 673 static struct nfs4_state *
 674 nfs4_alloc_open_state(void)
 675 {
 676         struct nfs4_state *state;
 677
 678         state = kzalloc(sizeof(*state), GFP_NOFS);
 679         if (!state)
 680                 return NULL;
 681         atomic_set(&state->count, 1);
 682         INIT_LIST_HEAD(&state->lock_states);
 683         spin_lock_init(&state->state_lock);
 684         seqlock_init(&state->seqlock);
 685         return state;
 686 }
 687
 688 void
 689 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
 690 {
 691         if (state->state == fmode)
 692                 return;
 693         /* NB! List reordering - see the reclaim code for why.  */
 694         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
 695                 if (fmode & FMODE_WRITE)
 696                         list_move(&state->open_states, &state->owner->so_states);
 697                 else
 698                         list_move_tail(&state->open_states, &state->owner->so_states);
 699         }
 700         state->state = fmode;
 701 }
 702
 703 static struct nfs4_state *
 704 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 705 {
 706         struct nfs_inode *nfsi = NFS_I(inode);
 707         struct nfs4_state *state;
 708
 709         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 710                 if (state->owner != owner)
 711                         continue;
 712                 if (atomic_inc_not_zero(&state->count))
 713                         return state;
 714         }
 715         return NULL;
 716 }
 717
 718 static void
 719 nfs4_free_open_state(struct nfs4_state *state)
 720 {
 721         kfree(state);
 722 }
 723
 724 struct nfs4_state *
 725 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 726 {
 727         struct nfs4_state *state, *new;
 728         struct nfs_inode *nfsi = NFS_I(inode);
 729
 730         spin_lock(&inode->i_lock);
 731         state = __nfs4_find_state_byowner(inode, owner);
 732         spin_unlock(&inode->i_lock);
 733         if (state)
 734                 goto out;
 735         new = nfs4_alloc_open_state();
 736         spin_lock(&owner->so_lock);
 737         spin_lock(&inode->i_lock);
 738         state = __nfs4_find_state_byowner(inode, owner);
 739         if (state == NULL && new != NULL) {
 740                 state = new;
 741                 state->owner = owner;
 742                 atomic_inc(&owner->so_count);
 743                 list_add(&state->inode_states, &nfsi->open_states);
 744                 ihold(inode);
 745                 state->inode = inode;
 746                 spin_unlock(&inode->i_lock);
 747                 /* Note: The reclaim code dictates that we add stateless
 748                  * and read-only stateids to the end of the list */
 749                 list_add_tail(&state->open_states, &owner->so_states);
 750                 spin_unlock(&owner->so_lock);
 751         } else {
 752                 spin_unlock(&inode->i_lock);
 753                 spin_unlock(&owner->so_lock);
 754                 if (new)
 755                         nfs4_free_open_state(new);
 756         }
 757 out:
 758         return state;
 759 }
 760
 761 void nfs4_put_open_state(struct nfs4_state *state)
 762 {
 763         struct inode *inode = state->inode;
 764         struct nfs4_state_owner *owner = state->owner;
 765
 766         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
 767                 return;
 768         spin_lock(&inode->i_lock);
 769         list_del(&state->inode_states);
 770         list_del(&state->open_states);
 771         spin_unlock(&inode->i_lock);
 772         spin_unlock(&owner->so_lock);
 773         iput(inode);
 774         nfs4_free_open_state(state);
 775         nfs4_put_state_owner(owner);
 776 }
 777
 778 /*
 779  * Close the current file.
 780  */
 781 static void __nfs4_close(struct nfs4_state *state,
 782                 fmode_t fmode, gfp_t gfp_mask, int wait)
 783 {
 784         struct nfs4_state_owner *owner = state->owner;
 785         int call_close = 0;
 786         fmode_t newstate;
 787
 788         atomic_inc(&owner->so_count);
 789         /* Protect against nfs4_find_state() */
 790         spin_lock(&owner->so_lock);
 791         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
 792                 case FMODE_READ:
 793                         state->n_rdonly--;
 794                         break;
 795                 case FMODE_WRITE:
 796                         state->n_wronly--;
 797                         break;
 798                 case FMODE_READ|FMODE_WRITE:
 799                         state->n_rdwr--;
 800         }
 801         newstate = FMODE_READ|FMODE_WRITE;
 802         if (state->n_rdwr == 0) {
 803                 if (state->n_rdonly == 0) {
 804                         newstate &= ~FMODE_READ;
 805                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
 806                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 807                 }
 808                 if (state->n_wronly == 0) {
 809                         newstate &= ~FMODE_WRITE;
 810                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
 811                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
 812                 }
 813                 if (newstate == 0)
 814                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
 815         }
 816         nfs4_state_set_mode_locked(state, newstate);
 817         spin_unlock(&owner->so_lock);
 818
 819         if (!call_close) {
 820                 nfs4_put_open_state(state);
 821                 nfs4_put_state_owner(owner);
 822         } else
 823                 nfs4_do_close(state, gfp_mask, wait);
 824 }
 825
 826 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
 827 {
 828         __nfs4_close(state, fmode, GFP_NOFS, 0);
 829 }
 830
 831 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
 832 {
 833         __nfs4_close(state, fmode, GFP_KERNEL, 1);
 834 }
 835
 836 /*
 837  * Search the state->lock_states for an existing lock_owner
 838  * that is compatible with current->files
 839  */
 840 static struct nfs4_lock_state *
 841 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 842 {
 843         struct nfs4_lock_state *pos;
 844         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 845                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
 846                         continue;
 847                 switch (pos->ls_owner.lo_type) {
 848                 case NFS4_POSIX_LOCK_TYPE:
 849                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
 850                                 continue;
 851                         break;
 852                 case NFS4_FLOCK_LOCK_TYPE:
 853                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
 854                                 continue;
 855                 }
 856                 atomic_inc(&pos->ls_count);
 857                 return pos;
 858         }
 859         return NULL;
 860 }
 861
 862 /*
 863  * Return a compatible lock_state. If no initialized lock_state structure
 864  * exists, return an uninitialized one.
 865  *
 866  */
 867 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
 868 {
 869         struct nfs4_lock_state *lsp;
 870         struct nfs_server *server = state->owner->so_server;
 871
 872         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
 873         if (lsp == NULL)
 874                 return NULL;
 875         nfs4_init_seqid_counter(&lsp->ls_seqid);
 876         atomic_set(&lsp->ls_count, 1);
 877         lsp->ls_state = state;
 878         lsp->ls_owner.lo_type = type;
 879         switch (lsp->ls_owner.lo_type) {
 880         case NFS4_FLOCK_LOCK_TYPE:
 881                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
 882                 break;
 883         case NFS4_POSIX_LOCK_TYPE:
 884                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
 885                 break;
 886         default:
 887                 goto out_free;
 888         }
 889         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
 890         if (lsp->ls_seqid.owner_id < 0)
 891                 goto out_free;
 892         INIT_LIST_HEAD(&lsp->ls_locks);
 893         return lsp;
 894 out_free:
 895         kfree(lsp);
 896         return NULL;
 897 }
 898
 899 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
 900 {
 901         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
 902         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
 903         kfree(lsp);
 904 }
 905
 906 /*
 907  * Return a compatible lock_state. If no initialized lock_state structure
 908  * exists, return an uninitialized one.
 909  *
 910  */
 911 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
 912 {
 913         struct nfs4_lock_state *lsp, *new = NULL;
 914
 915         for(;;) {
 916                 spin_lock(&state->state_lock);
 917                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
 918                 if (lsp != NULL)
 919                         break;
 920                 if (new != NULL) {
 921                         list_add(&new->ls_locks, &state->lock_states);
 922                         set_bit(LK_STATE_IN_USE, &state->flags);
 923                         lsp = new;
 924                         new = NULL;
 925                         break;
 926                 }
 927                 spin_unlock(&state->state_lock);
 928                 new = nfs4_alloc_lock_state(state, owner, pid, type);
 929                 if (new == NULL)
 930                         return NULL;
 931         }
 932         spin_unlock(&state->state_lock);
 933         if (new != NULL)
 934                 nfs4_free_lock_state(state->owner->so_server, new);
 935         return lsp;
 936 }
 937
 938 /*
 939  * Release reference to lock_state, and free it if we see that
 940  * it is no longer in use
 941  */
 942 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 943 {
 944         struct nfs4_state *state;
 945
 946         if (lsp == NULL)
 947                 return;
 948         state = lsp->ls_state;
 949         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
 950                 return;
 951         list_del(&lsp->ls_locks);
 952         if (list_empty(&state->lock_states))
 953                 clear_bit(LK_STATE_IN_USE, &state->flags);
 954         spin_unlock(&state->state_lock);
 955         if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
 956                 if (nfs4_release_lockowner(lsp) == 0)
 957                         return;
 958         }
 959         nfs4_free_lock_state(lsp->ls_state->owner->so_server, lsp);
 960 }
 961
 962 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
 963 {
 964         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
 965
 966         dst->fl_u.nfs4_fl.owner = lsp;
 967         atomic_inc(&lsp->ls_count);
 968 }
 969
 970 static void nfs4_fl_release_lock(struct file_lock *fl)
 971 {
 972         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
 973 }
 974
 975 static const struct file_lock_operations nfs4_fl_lock_ops = {
 976         .fl_copy_lock = nfs4_fl_copy_lock,
 977         .fl_release_private = nfs4_fl_release_lock,
 978 };
 979
 980 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 981 {
 982         struct nfs4_lock_state *lsp;
 983
 984         if (fl->fl_ops != NULL)
 985                 return 0;
 986         if (fl->fl_flags & FL_POSIX)
 987                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
 988         else if (fl->fl_flags & FL_FLOCK)
 989                 lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
 990                                 NFS4_FLOCK_LOCK_TYPE);
 991         else
 992                 return -EINVAL;
 993         if (lsp == NULL)
 994                 return -ENOMEM;
 995         fl->fl_u.nfs4_fl.owner = lsp;
 996         fl->fl_ops = &nfs4_fl_lock_ops;
 997         return 0;
 998 }
 999
1000 static bool nfs4_copy_lock_stateid(nfs4_stateid *dst, struct nfs4_state *state,
1001                 const struct nfs_lockowner *lockowner)
1002 {
1003         struct nfs4_lock_state *lsp;
1004         fl_owner_t fl_owner;
1005         pid_t fl_pid;
1006         bool ret = false;
1007
1008
1009         if (lockowner == NULL)
1010                 goto out;
1011
1012         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
1013                 goto out;
1014
1015         fl_owner = lockowner->l_owner;
1016         fl_pid = lockowner->l_pid;
1017         spin_lock(&state->state_lock);
1018         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
1019         if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
1020                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
1021                 ret = true;
1022         }
1023         spin_unlock(&state->state_lock);
1024         nfs4_put_lock_state(lsp);
1025 out:
1026         return ret;
1027 }
1028
1029 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
1030 {
1031         int seq;
1032
1033         do {
1034                 seq = read_seqbegin(&state->seqlock);
1035                 nfs4_stateid_copy(dst, &state->stateid);
1036         } while (read_seqretry(&state->seqlock, seq));
1037 }
1038
1039 /*
1040  * Byte-range lock aware utility to initialize the stateid of read/write
1041  * requests.
1042  */
1043 void nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
1044                 fmode_t fmode, const struct nfs_lockowner *lockowner)
1045 {
1046         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
1047                 return;
1048         if (nfs4_copy_lock_stateid(dst, state, lockowner))
1049                 return;
1050         nfs4_copy_open_stateid(dst, state);
1051 }
1052
1053 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
1054 {
1055         struct nfs_seqid *new;
1056
1057         new = kmalloc(sizeof(*new), gfp_mask);
1058         if (new != NULL) {
1059                 new->sequence = counter;
1060                 INIT_LIST_HEAD(&new->list);
1061                 new->task = NULL;
1062         }
1063         return new;
1064 }
1065
1066 void nfs_release_seqid(struct nfs_seqid *seqid)
1067 {
1068         struct nfs_seqid_counter *sequence;
1069
1070         if (list_empty(&seqid->list))
1071                 return;
1072         sequence = seqid->sequence;
1073         spin_lock(&sequence->lock);
1074         list_del_init(&seqid->list);
1075         if (!list_empty(&sequence->list)) {
1076                 struct nfs_seqid *next;
1077
1078                 next = list_first_entry(&sequence->list,
1079                                 struct nfs_seqid, list);
1080                 rpc_wake_up_queued_task(&sequence->wait, next->task);
1081         }
1082         spin_unlock(&sequence->lock);
1083 }
1084
1085 void nfs_free_seqid(struct nfs_seqid *seqid)
1086 {
1087         nfs_release_seqid(seqid);
1088         kfree(seqid);
1089 }
1090
1091 /*
1092  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
1093  * failed with a seqid incrementing error -
1094  * see comments nfs_fs.h:seqid_mutating_error()
1095  */
1096 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
1097 {
1098         switch (status) {
1099                 case 0:
1100                         break;
1101                 case -NFS4ERR_BAD_SEQID:
1102                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1103                                 return;
1104                         pr_warn_ratelimited("NFS: v4 server returned a bad"
1105                                         " sequence-id error on an"
1106                                         " unconfirmed sequence %p!\n",
1107                                         seqid->sequence);
1108                 case -NFS4ERR_STALE_CLIENTID:
1109                 case -NFS4ERR_STALE_STATEID:
1110                 case -NFS4ERR_BAD_STATEID:
1111                 case -NFS4ERR_BADXDR:
1112                 case -NFS4ERR_RESOURCE:
1113                 case -NFS4ERR_NOFILEHANDLE:
1114                         /* Non-seqid mutating errors */
1115                         return;
1116         };
1117         /*
1118          * Note: no locking needed as we are guaranteed to be first
1119          * on the sequence list
1120          */
1121         seqid->sequence->counter++;
1122 }
1123
1124 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1125 {
1126         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1127                                         struct nfs4_state_owner, so_seqid);
1128         struct nfs_server *server = sp->so_server;
1129
1130         if (status == -NFS4ERR_BAD_SEQID)
1131                 nfs4_drop_state_owner(sp);
1132         if (!nfs4_has_session(server->nfs_client))
1133                 nfs_increment_seqid(status, seqid);
1134 }
1135
1136 /*
1137  * Increment the seqid if the LOCK/LOCKU succeeded, or
1138  * failed with a seqid incrementing error -
1139  * see comments nfs_fs.h:seqid_mutating_error()
1140  */
1141 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1142 {
1143         nfs_increment_seqid(status, seqid);
1144 }
1145
1146 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1147 {
1148         struct nfs_seqid_counter *sequence = seqid->sequence;
1149         int status = 0;
1150
1151         spin_lock(&sequence->lock);
1152         seqid->task = task;
1153         if (list_empty(&seqid->list))
1154                 list_add_tail(&seqid->list, &sequence->list);
1155         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1156                 goto unlock;
1157         rpc_sleep_on(&sequence->wait, task, NULL);
1158         status = -EAGAIN;
1159 unlock:
1160         spin_unlock(&sequence->lock);
1161         return status;
1162 }
1163
1164 static int nfs4_run_state_manager(void *);
1165
1166 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1167 {
1168         smp_mb__before_clear_bit();
1169         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1170         smp_mb__after_clear_bit();
1171         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1172         rpc_wake_up(&clp->cl_rpcwaitq);
1173 }
1174
1175 /*
1176  * Schedule the nfs_client asynchronous state management routine
1177  */
1178 void nfs4_schedule_state_manager(struct nfs_client *clp)
1179 {
1180         struct task_struct *task;
1181         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1182
1183         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1184                 return;
1185         __module_get(THIS_MODULE);
1186         atomic_inc(&clp->cl_count);
1187
1188         /* The rcu_read_lock() is not strictly necessary, as the state
1189          * manager is the only thread that ever changes the rpc_xprt
1190          * after it's initialized.  At this point, we're single threaded. */
1191         rcu_read_lock();
1192         snprintf(buf, sizeof(buf), "%s-manager",
1193                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1194         rcu_read_unlock();
1195         task = kthread_run(nfs4_run_state_manager, clp, buf);
1196         if (IS_ERR(task)) {
1197                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1198                         __func__, PTR_ERR(task));
1199                 nfs4_clear_state_manager_bit(clp);
1200                 nfs_put_client(clp);
1201                 module_put(THIS_MODULE);
1202         }
1203 }
1204
1205 /*
1206  * Schedule a lease recovery attempt
1207  */
1208 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1209 {
1210         if (!clp)
1211                 return;
1212         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1213                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1214         dprintk("%s: scheduling lease recovery for server %s\n", __func__,
1215                         clp->cl_hostname);
1216         nfs4_schedule_state_manager(clp);
1217 }
1218 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1219
1220 int nfs4_wait_clnt_recover(struct nfs_client *clp)
1221 {
1222         int res;
1223
1224         might_sleep();
1225
1226         res = wait_on_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
1227                         nfs_wait_bit_killable, TASK_KILLABLE);
1228         if (res)
1229                 return res;
1230
1231         if (clp->cl_cons_state < 0)
1232                 return clp->cl_cons_state;
1233         return 0;
1234 }
1235
1236 int nfs4_client_recover_expired_lease(struct nfs_client *clp)
1237 {
1238         unsigned int loop;
1239         int ret;
1240
1241         for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) {
1242                 ret = nfs4_wait_clnt_recover(clp);
1243                 if (ret != 0)
1244                         break;
1245                 if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) &&
1246                     !test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state))
1247                         break;
1248                 nfs4_schedule_state_manager(clp);
1249                 ret = -EIO;
1250         }
1251         return ret;
1252 }
1253
1254 /*
1255  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1256  * @clp: client to process
1257  *
1258  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1259  * resend of the SETCLIENTID and hence re-establish the
1260  * callback channel. Then return all existing delegations.
1261  */
1262 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1263 {
1264         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1265         nfs_expire_all_delegations(clp);
1266         dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__,
1267                         clp->cl_hostname);
1268 }
1269
1270 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1271 {
1272         nfs40_handle_cb_pathdown(clp);
1273         nfs4_schedule_state_manager(clp);
1274 }
1275
1276 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1277 {
1278
1279         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1280         /* Don't recover state that expired before the reboot */
1281         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1282                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1283                 return 0;
1284         }
1285         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1286         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1287         return 1;
1288 }
1289
1290 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1291 {
1292         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1293         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1294         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1295         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1296         return 1;
1297 }
1298
1299 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1300 {
1301         struct nfs_client *clp = server->nfs_client;
1302
1303         nfs4_state_mark_reclaim_nograce(clp, state);
1304         dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
1305                         clp->cl_hostname);
1306         nfs4_schedule_state_manager(clp);
1307 }
1308 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1309
1310 void nfs_inode_find_state_and_recover(struct inode *inode,
1311                 const nfs4_stateid *stateid)
1312 {
1313         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1314         struct nfs_inode *nfsi = NFS_I(inode);
1315         struct nfs_open_context *ctx;
1316         struct nfs4_state *state;
1317         bool found = false;
1318
1319         spin_lock(&inode->i_lock);
1320         list_for_each_entry(ctx, &nfsi->open_files, list) {
1321                 state = ctx->state;
1322                 if (state == NULL)
1323                         continue;
1324                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1325                         continue;
1326                 if (!nfs4_stateid_match(&state->stateid, stateid))
1327                         continue;
1328                 nfs4_state_mark_reclaim_nograce(clp, state);
1329                 found = true;
1330         }
1331         spin_unlock(&inode->i_lock);
1332         if (found)
1333                 nfs4_schedule_state_manager(clp);
1334 }
1335
1336
1337 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1338 {
1339         struct inode *inode = state->inode;
1340         struct nfs_inode *nfsi = NFS_I(inode);
1341         struct file_lock *fl;
1342         int status = 0;
1343
1344         if (inode->i_flock == NULL)
1345                 return 0;
1346
1347         /* Guard against delegation returns and new lock/unlock calls */
1348         down_write(&nfsi->rwsem);
1349         /* Protect inode->i_flock using the BKL */
1350         lock_flocks();
1351         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1352                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1353                         continue;
1354                 if (nfs_file_open_context(fl->fl_file)->state != state)
1355                         continue;
1356                 unlock_flocks();
1357                 status = ops->recover_lock(state, fl);
1358                 switch (status) {
1359                         case 0:
1360                                 break;
1361                         case -ESTALE:
1362                         case -NFS4ERR_ADMIN_REVOKED:
1363                         case -NFS4ERR_STALE_STATEID:
1364                         case -NFS4ERR_BAD_STATEID:
1365                         case -NFS4ERR_EXPIRED:
1366                         case -NFS4ERR_NO_GRACE:
1367                         case -NFS4ERR_STALE_CLIENTID:
1368                         case -NFS4ERR_BADSESSION:
1369                         case -NFS4ERR_BADSLOT:
1370                         case -NFS4ERR_BAD_HIGH_SLOT:
1371                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1372                                 goto out;
1373                         default:
1374                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1375                                         "Zeroing state\n", __func__, status);
1376                         case -ENOMEM:
1377                         case -NFS4ERR_DENIED:
1378                         case -NFS4ERR_RECLAIM_BAD:
1379                         case -NFS4ERR_RECLAIM_CONFLICT:
1380                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1381                                 status = 0;
1382                 }
1383                 lock_flocks();
1384         }
1385         unlock_flocks();
1386 out:
1387         up_write(&nfsi->rwsem);
1388         return status;
1389 }
1390
1391 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1392 {
1393         struct nfs4_state *state;
1394         struct nfs4_lock_state *lock;
1395         int status = 0;
1396
1397         /* Note: we rely on the sp->so_states list being ordered
1398          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1399          * states first.
1400          * This is needed to ensure that the server won't give us any
1401          * read delegations that we have to return if, say, we are
1402          * recovering after a network partition or a reboot from a
1403          * server that doesn't support a grace period.
1404          */
1405 restart:
1406         spin_lock(&sp->so_lock);
1407         list_for_each_entry(state, &sp->so_states, open_states) {
1408                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1409                         continue;
1410                 if (state->state == 0)
1411                         continue;
1412                 atomic_inc(&state->count);
1413                 spin_unlock(&sp->so_lock);
1414                 status = ops->recover_open(sp, state);
1415                 if (status >= 0) {
1416                         status = nfs4_reclaim_locks(state, ops);
1417                         if (status >= 0) {
1418                                 spin_lock(&state->state_lock);
1419                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1420                                         if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
1421                                                 pr_warn_ratelimited("NFS: "
1422                                                         "%s: Lock reclaim "
1423                                                         "failed!\n", __func__);
1424                                 }
1425                                 spin_unlock(&state->state_lock);
1426                                 nfs4_put_open_state(state);
1427                                 goto restart;
1428                         }
1429                 }
1430                 switch (status) {
1431                         default:
1432                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1433                                         "Zeroing state\n", __func__, status);
1434                         case -ENOENT:
1435                         case -ENOMEM:
1436                         case -ESTALE:
1437                                 /*
1438                                  * Open state on this file cannot be recovered
1439                                  * All we can do is revert to using the zero stateid.
1440                                  */
1441                                 memset(&state->stateid, 0,
1442                                         sizeof(state->stateid));
1443                                 /* Mark the file as being 'closed' */
1444                                 state->state = 0;
1445                                 break;
1446                         case -EKEYEXPIRED:
1447                                 /*
1448                                  * User RPCSEC_GSS context has expired.
1449                                  * We cannot recover this stateid now, so
1450                                  * skip it and allow recovery thread to
1451                                  * proceed.
1452                                  */
1453                                 break;
1454                         case -NFS4ERR_ADMIN_REVOKED:
1455                         case -NFS4ERR_STALE_STATEID:
1456                         case -NFS4ERR_BAD_STATEID:
1457                         case -NFS4ERR_RECLAIM_BAD:
1458                         case -NFS4ERR_RECLAIM_CONFLICT:
1459                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1460                                 break;
1461                         case -NFS4ERR_EXPIRED:
1462                         case -NFS4ERR_NO_GRACE:
1463                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1464                         case -NFS4ERR_STALE_CLIENTID:
1465                         case -NFS4ERR_BADSESSION:
1466                         case -NFS4ERR_BADSLOT:
1467                         case -NFS4ERR_BAD_HIGH_SLOT:
1468                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1469                                 goto out_err;
1470                 }
1471                 nfs4_put_open_state(state);
1472                 goto restart;
1473         }
1474         spin_unlock(&sp->so_lock);
1475         return 0;
1476 out_err:
1477         nfs4_put_open_state(state);
1478         return status;
1479 }
1480
1481 static void nfs4_clear_open_state(struct nfs4_state *state)
1482 {
1483         struct nfs4_lock_state *lock;
1484
1485         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1486         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1487         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1488         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1489         spin_lock(&state->state_lock);
1490         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1491                 lock->ls_seqid.flags = 0;
1492                 clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags);
1493         }
1494         spin_unlock(&state->state_lock);
1495 }
1496
1497 static void nfs4_reset_seqids(struct nfs_server *server,
1498         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1499 {
1500         struct nfs_client *clp = server->nfs_client;
1501         struct nfs4_state_owner *sp;
1502         struct rb_node *pos;
1503         struct nfs4_state *state;
1504
1505         spin_lock(&clp->cl_lock);
1506         for (pos = rb_first(&server->state_owners);
1507              pos != NULL;
1508              pos = rb_next(pos)) {
1509                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1510                 sp->so_seqid.flags = 0;
1511                 spin_lock(&sp->so_lock);
1512                 list_for_each_entry(state, &sp->so_states, open_states) {
1513                         if (mark_reclaim(clp, state))
1514                                 nfs4_clear_open_state(state);
1515                 }
1516                 spin_unlock(&sp->so_lock);
1517         }
1518         spin_unlock(&clp->cl_lock);
1519 }
1520
1521 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1522         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1523 {
1524         struct nfs_server *server;
1525
1526         rcu_read_lock();
1527         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1528                 nfs4_reset_seqids(server, mark_reclaim);
1529         rcu_read_unlock();
1530 }
1531
1532 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1533 {
1534         /* Mark all delegations for reclaim */
1535         nfs_delegation_mark_reclaim(clp);
1536         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1537 }
1538
1539 static void nfs4_reclaim_complete(struct nfs_client *clp,
1540                                  const struct nfs4_state_recovery_ops *ops)
1541 {
1542         /* Notify the server we're done reclaiming our state */
1543         if (ops->reclaim_complete)
1544                 (void)ops->reclaim_complete(clp);
1545 }
1546
1547 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1548 {
1549         struct nfs_client *clp = server->nfs_client;
1550         struct nfs4_state_owner *sp;
1551         struct rb_node *pos;
1552         struct nfs4_state *state;
1553
1554         spin_lock(&clp->cl_lock);
1555         for (pos = rb_first(&server->state_owners);
1556              pos != NULL;
1557              pos = rb_next(pos)) {
1558                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1559                 spin_lock(&sp->so_lock);
1560                 list_for_each_entry(state, &sp->so_states, open_states) {
1561                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1562                                                 &state->flags))
1563                                 continue;
1564                         nfs4_state_mark_reclaim_nograce(clp, state);
1565                 }
1566                 spin_unlock(&sp->so_lock);
1567         }
1568         spin_unlock(&clp->cl_lock);
1569 }
1570
1571 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1572 {
1573         struct nfs_server *server;
1574
1575         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1576                 return 0;
1577
1578         rcu_read_lock();
1579         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1580                 nfs4_clear_reclaim_server(server);
1581         rcu_read_unlock();
1582
1583         nfs_delegation_reap_unclaimed(clp);
1584         return 1;
1585 }
1586
1587 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1588 {
1589         if (!nfs4_state_clear_reclaim_reboot(clp))
1590                 return;
1591         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1592 }
1593
1594 static void nfs_delegation_clear_all(struct nfs_client *clp)
1595 {
1596         nfs_delegation_mark_reclaim(clp);
1597         nfs_delegation_reap_unclaimed(clp);
1598 }
1599
1600 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1601 {
1602         nfs_delegation_clear_all(clp);
1603         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1604 }
1605
1606 static void nfs4_warn_keyexpired(const char *s)
1607 {
1608         printk_ratelimited(KERN_WARNING "Error: state manager"
1609                         " encountered RPCSEC_GSS session"
1610                         " expired against NFSv4 server %s.\n",
1611                         s);
1612 }
1613
1614 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1615 {
1616         switch (error) {
1617                 case 0:
1618                         break;
1619                 case -NFS4ERR_CB_PATH_DOWN:
1620                         nfs40_handle_cb_pathdown(clp);
1621                         break;
1622                 case -NFS4ERR_NO_GRACE:
1623                         nfs4_state_end_reclaim_reboot(clp);
1624                         break;
1625                 case -NFS4ERR_STALE_CLIENTID:
1626                 case -NFS4ERR_LEASE_MOVED:
1627                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1628                         nfs4_state_clear_reclaim_reboot(clp);
1629                         nfs4_state_start_reclaim_reboot(clp);
1630                         break;
1631                 case -NFS4ERR_EXPIRED:
1632                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1633                         nfs4_state_start_reclaim_nograce(clp);
1634                         break;
1635                 case -NFS4ERR_BADSESSION:
1636                 case -NFS4ERR_BADSLOT:
1637                 case -NFS4ERR_BAD_HIGH_SLOT:
1638                 case -NFS4ERR_DEADSESSION:
1639                 case -NFS4ERR_SEQ_FALSE_RETRY:
1640                 case -NFS4ERR_SEQ_MISORDERED:
1641                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1642                         /* Zero session reset errors */
1643                         break;
1644                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1645                         set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1646                         break;
1647                 case -EKEYEXPIRED:
1648                         /* Nothing we can do */
1649                         nfs4_warn_keyexpired(clp->cl_hostname);
1650                         break;
1651                 default:
1652                         dprintk("%s: failed to handle error %d for server %s\n",
1653                                         __func__, error, clp->cl_hostname);
1654                         return error;
1655         }
1656         dprintk("%s: handled error %d for server %s\n", __func__, error,
1657                         clp->cl_hostname);
1658         return 0;
1659 }
1660
1661 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1662 {
1663         struct nfs4_state_owner *sp;
1664         struct nfs_server *server;
1665         struct rb_node *pos;
1666         int status = 0;
1667
1668 restart:
1669         rcu_read_lock();
1670         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1671                 nfs4_purge_state_owners(server);
1672                 spin_lock(&clp->cl_lock);
1673                 for (pos = rb_first(&server->state_owners);
1674                      pos != NULL;
1675                      pos = rb_next(pos)) {
1676                         sp = rb_entry(pos,
1677                                 struct nfs4_state_owner, so_server_node);
1678                         if (!test_and_clear_bit(ops->owner_flag_bit,
1679                                                         &sp->so_flags))
1680                                 continue;
1681                         atomic_inc(&sp->so_count);
1682                         spin_unlock(&clp->cl_lock);
1683                         rcu_read_unlock();
1684
1685                         status = nfs4_reclaim_open_state(sp, ops);
1686                         if (status < 0) {
1687                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1688                                 nfs4_put_state_owner(sp);
1689                                 return nfs4_recovery_handle_error(clp, status);
1690                         }
1691
1692                         nfs4_put_state_owner(sp);
1693                         goto restart;
1694                 }
1695                 spin_unlock(&clp->cl_lock);
1696         }
1697         rcu_read_unlock();
1698         return status;
1699 }
1700
1701 static int nfs4_check_lease(struct nfs_client *clp)
1702 {
1703         struct rpc_cred *cred;
1704         const struct nfs4_state_maintenance_ops *ops =
1705                 clp->cl_mvops->state_renewal_ops;
1706         int status;
1707
1708         /* Is the client already known to have an expired lease? */
1709         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1710                 return 0;
1711         spin_lock(&clp->cl_lock);
1712         cred = ops->get_state_renewal_cred_locked(clp);
1713         spin_unlock(&clp->cl_lock);
1714         if (cred == NULL) {
1715                 cred = nfs4_get_setclientid_cred(clp);
1716                 status = -ENOKEY;
1717                 if (cred == NULL)
1718                         goto out;
1719         }
1720         status = ops->renew_lease(clp, cred);
1721         put_rpccred(cred);
1722 out:
1723         return nfs4_recovery_handle_error(clp, status);
1724 }
1725
1726 /* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors
1727  * and for recoverable errors on EXCHANGE_ID for v4.1
1728  */
1729 static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
1730 {
1731         switch (status) {
1732         case -NFS4ERR_SEQ_MISORDERED:
1733                 if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
1734                         return -ESERVERFAULT;
1735                 /* Lease confirmation error: retry after purging the lease */
1736                 ssleep(1);
1737                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1738                 break;
1739         case -NFS4ERR_STALE_CLIENTID:
1740                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1741                 nfs4_state_clear_reclaim_reboot(clp);
1742                 nfs4_state_start_reclaim_reboot(clp);
1743                 break;
1744         case -NFS4ERR_CLID_INUSE:
1745                 pr_err("NFS: Server %s reports our clientid is in use\n",
1746                         clp->cl_hostname);
1747                 nfs_mark_client_ready(clp, -EPERM);
1748                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1749                 return -EPERM;
1750         case -EACCES:
1751                 if (clp->cl_machine_cred == NULL)
1752                         return -EACCES;
1753                 /* Handle case where the user hasn't set up machine creds */
1754                 nfs4_clear_machine_cred(clp);
1755         case -NFS4ERR_DELAY:
1756         case -ETIMEDOUT:
1757         case -EAGAIN:
1758                 ssleep(1);
1759                 break;
1760
1761         case -NFS4ERR_MINOR_VERS_MISMATCH:
1762                 if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1763                         nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
1764                 dprintk("%s: exit with error %d for server %s\n",
1765                                 __func__, -EPROTONOSUPPORT, clp->cl_hostname);
1766                 return -EPROTONOSUPPORT;
1767         case -EKEYEXPIRED:
1768                 nfs4_warn_keyexpired(clp->cl_hostname);
1769         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1770                                  * in nfs4_exchange_id */
1771         default:
1772                 dprintk("%s: exit with error %d for server %s\n", __func__,
1773                                 status, clp->cl_hostname);
1774                 return status;
1775         }
1776         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1777         dprintk("%s: handled error %d for server %s\n", __func__, status,
1778                         clp->cl_hostname);
1779         return 0;
1780 }
1781
1782 static int nfs4_establish_lease(struct nfs_client *clp)
1783 {
1784         struct rpc_cred *cred;
1785         const struct nfs4_state_recovery_ops *ops =
1786                 clp->cl_mvops->reboot_recovery_ops;
1787         int status;
1788
1789         cred = ops->get_clid_cred(clp);
1790         if (cred == NULL)
1791                 return -ENOENT;
1792         status = ops->establish_clid(clp, cred);
1793         put_rpccred(cred);
1794         if (status != 0)
1795                 return status;
1796         pnfs_destroy_all_layouts(clp);
1797         return 0;
1798 }
1799
1800 /*
1801  * Returns zero or a negative errno.  NFS4ERR values are converted
1802  * to local errno values.
1803  */
1804 static int nfs4_reclaim_lease(struct nfs_client *clp)
1805 {
1806         int status;
1807
1808         status = nfs4_establish_lease(clp);
1809         if (status < 0)
1810                 return nfs4_handle_reclaim_lease_error(clp, status);
1811         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state))
1812                 nfs4_state_start_reclaim_nograce(clp);
1813         if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1814                 set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1815         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1816         clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1817         return 0;
1818 }
1819
1820 static int nfs4_purge_lease(struct nfs_client *clp)
1821 {
1822         int status;
1823
1824         status = nfs4_establish_lease(clp);
1825         if (status < 0)
1826                 return nfs4_handle_reclaim_lease_error(clp, status);
1827         clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1828         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1829         nfs4_state_start_reclaim_nograce(clp);
1830         return 0;
1831 }
1832
1833 /**
1834  * nfs4_discover_server_trunking - Detect server IP address trunking
1835  *
1836  * @clp: nfs_client under test
1837  * @result: OUT: found nfs_client, or clp
1838  *
1839  * Returns zero or a negative errno.  If zero is returned,
1840  * an nfs_client pointer is planted in "result".
1841  *
1842  * Note: since we are invoked in process context, and
1843  * not from inside the state manager, we cannot use
1844  * nfs4_handle_reclaim_lease_error().
1845  */
1846 int nfs4_discover_server_trunking(struct nfs_client *clp,
1847                                   struct nfs_client **result)
1848 {
1849         const struct nfs4_state_recovery_ops *ops =
1850                                 clp->cl_mvops->reboot_recovery_ops;
1851         rpc_authflavor_t *flavors, flav, save;
1852         struct rpc_clnt *clnt;
1853         struct rpc_cred *cred;
1854         int i, len, status;
1855
1856         dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
1857
1858         len = NFS_MAX_SECFLAVORS;
1859         flavors = kcalloc(len, sizeof(*flavors), GFP_KERNEL);
1860         if (flavors == NULL) {
1861                 status = -ENOMEM;
1862                 goto out;
1863         }
1864         len = rpcauth_list_flavors(flavors, len);
1865         if (len < 0) {
1866                 status = len;
1867                 goto out_free;
1868         }
1869         clnt = clp->cl_rpcclient;
1870         save = clnt->cl_auth->au_flavor;
1871         i = 0;
1872
1873         mutex_lock(&nfs_clid_init_mutex);
1874         status  = -ENOENT;
1875 again:
1876         cred = ops->get_clid_cred(clp);
1877         if (cred == NULL)
1878                 goto out_unlock;
1879
1880         status = ops->detect_trunking(clp, result, cred);
1881         put_rpccred(cred);
1882         switch (status) {
1883         case 0:
1884                 break;
1885
1886         case -EACCES:
1887                 if (clp->cl_machine_cred == NULL)
1888                         break;
1889                 /* Handle case where the user hasn't set up machine creds */
1890                 nfs4_clear_machine_cred(clp);
1891         case -NFS4ERR_DELAY:
1892         case -ETIMEDOUT:
1893         case -EAGAIN:
1894                 ssleep(1);
1895                 dprintk("NFS: %s after status %d, retrying\n",
1896                         __func__, status);
1897                 goto again;
1898
1899         case -NFS4ERR_CLID_INUSE:
1900         case -NFS4ERR_WRONGSEC:
1901                 status = -EPERM;
1902                 if (i >= len)
1903                         break;
1904
1905                 flav = flavors[i++];
1906                 if (flav == save)
1907                         flav = flavors[i++];
1908                 clnt = rpc_clone_client_set_auth(clnt, flav);
1909                 if (IS_ERR(clnt)) {
1910                         status = PTR_ERR(clnt);
1911                         break;
1912                 }
1913                 clp->cl_rpcclient = clnt;
1914                 goto again;
1915
1916         case -NFS4ERR_MINOR_VERS_MISMATCH:
1917                 status = -EPROTONOSUPPORT;
1918                 break;
1919
1920         case -EKEYEXPIRED:
1921                 nfs4_warn_keyexpired(clp->cl_hostname);
1922         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1923                                  * in nfs4_exchange_id */
1924                 status = -EKEYEXPIRED;
1925         }
1926
1927 out_unlock:
1928         mutex_unlock(&nfs_clid_init_mutex);
1929 out_free:
1930         kfree(flavors);
1931 out:
1932         dprintk("NFS: %s: status = %d\n", __func__, status);
1933         return status;
1934 }
1935
1936 #ifdef CONFIG_NFS_V4_1
1937 void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
1938 {
1939         struct nfs_client *clp = session->clp;
1940
1941         switch (err) {
1942         default:
1943                 set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1944                 break;
1945         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1946                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1947         }
1948         nfs4_schedule_lease_recovery(clp);
1949 }
1950 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1951
1952 static void nfs41_ping_server(struct nfs_client *clp)
1953 {
1954         /* Use CHECK_LEASE to ping the server with a SEQUENCE */
1955         set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1956         nfs4_schedule_state_manager(clp);
1957 }
1958
1959 void nfs41_server_notify_target_slotid_update(struct nfs_client *clp)
1960 {
1961         nfs41_ping_server(clp);
1962 }
1963
1964 void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp)
1965 {
1966         nfs41_ping_server(clp);
1967 }
1968
1969 static void nfs4_reset_all_state(struct nfs_client *clp)
1970 {
1971         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1972                 set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1973                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1974                 nfs4_state_start_reclaim_nograce(clp);
1975                 dprintk("%s: scheduling reset of all state for server %s!\n",
1976                                 __func__, clp->cl_hostname);
1977                 nfs4_schedule_state_manager(clp);
1978         }
1979 }
1980
1981 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1982 {
1983         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1984                 nfs4_state_start_reclaim_reboot(clp);
1985                 dprintk("%s: server %s rebooted!\n", __func__,
1986                                 clp->cl_hostname);
1987                 nfs4_schedule_state_manager(clp);
1988         }
1989 }
1990
1991 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1992 {
1993         nfs4_reset_all_state(clp);
1994         dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
1995 }
1996
1997 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1998 {
1999         /* This will need to handle layouts too */
2000         nfs_expire_all_delegations(clp);
2001         dprintk("%s: Recallable state revoked on server %s!\n", __func__,
2002                         clp->cl_hostname);
2003 }
2004
2005 static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
2006 {
2007         nfs_expire_all_delegations(clp);
2008         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
2009                 nfs4_schedule_state_manager(clp);
2010         dprintk("%s: server %s declared a backchannel fault\n", __func__,
2011                         clp->cl_hostname);
2012 }
2013
2014 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
2015 {
2016         if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2017                 &clp->cl_state) == 0)
2018                 nfs4_schedule_state_manager(clp);
2019 }
2020
2021 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
2022 {
2023         if (!flags)
2024                 return;
2025
2026         dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
2027                 __func__, clp->cl_hostname, clp->cl_clientid, flags);
2028
2029         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
2030                 nfs41_handle_server_reboot(clp);
2031         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
2032                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
2033                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
2034                             SEQ4_STATUS_LEASE_MOVED))
2035                 nfs41_handle_state_revoked(clp);
2036         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
2037                 nfs41_handle_recallable_state_revoked(clp);
2038         if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
2039                 nfs41_handle_backchannel_fault(clp);
2040         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
2041                                 SEQ4_STATUS_CB_PATH_DOWN_SESSION))
2042                 nfs41_handle_cb_path_down(clp);
2043 }
2044
2045 static int nfs4_reset_session(struct nfs_client *clp)
2046 {
2047         struct rpc_cred *cred;
2048         int status;
2049
2050         if (!nfs4_has_session(clp))
2051                 return 0;
2052         nfs4_begin_drain_session(clp);
2053         cred = nfs4_get_exchange_id_cred(clp);
2054         status = nfs4_proc_destroy_session(clp->cl_session, cred);
2055         if (status && status != -NFS4ERR_BADSESSION &&
2056             status != -NFS4ERR_DEADSESSION) {
2057                 status = nfs4_recovery_handle_error(clp, status);
2058                 goto out;
2059         }
2060
2061         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
2062         status = nfs4_proc_create_session(clp, cred);
2063         if (status) {
2064                 dprintk("%s: session reset failed with status %d for server %s!\n",
2065                         __func__, status, clp->cl_hostname);
2066                 status = nfs4_handle_reclaim_lease_error(clp, status);
2067                 goto out;
2068         }
2069         nfs41_finish_session_reset(clp);
2070         dprintk("%s: session reset was successful for server %s!\n",
2071                         __func__, clp->cl_hostname);
2072 out:
2073         if (cred)
2074                 put_rpccred(cred);
2075         return status;
2076 }
2077
2078 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2079 {
2080         struct rpc_cred *cred;
2081         int ret;
2082
2083         if (!nfs4_has_session(clp))
2084                 return 0;
2085         nfs4_begin_drain_session(clp);
2086         cred = nfs4_get_exchange_id_cred(clp);
2087         ret = nfs4_proc_bind_conn_to_session(clp, cred);
2088         if (cred)
2089                 put_rpccred(cred);
2090         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2091         switch (ret) {
2092         case 0:
2093                 dprintk("%s: bind_conn_to_session was successful for server %s!\n",
2094                         __func__, clp->cl_hostname);
2095                 break;
2096         case -NFS4ERR_DELAY:
2097                 ssleep(1);
2098                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2099                 break;
2100         default:
2101                 return nfs4_recovery_handle_error(clp, ret);
2102         }
2103         return 0;
2104 }
2105 #else /* CONFIG_NFS_V4_1 */
2106 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
2107 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
2108
2109 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2110 {
2111         return 0;
2112 }
2113 #endif /* CONFIG_NFS_V4_1 */
2114
2115 static void nfs4_state_manager(struct nfs_client *clp)
2116 {
2117         int status = 0;
2118         const char *section = "", *section_sep = "";
2119
2120         /* Ensure exclusive access to NFSv4 state */
2121         do {
2122                 if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
2123                         section = "purge state";
2124                         status = nfs4_purge_lease(clp);
2125                         if (status < 0)
2126                                 goto out_error;
2127                         continue;
2128                 }
2129
2130                 if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
2131                         section = "lease expired";
2132                         /* We're going to have to re-establish a clientid */
2133                         status = nfs4_reclaim_lease(clp);
2134                         if (status < 0)
2135                                 goto out_error;
2136                         continue;
2137                 }
2138
2139                 /* Initialize or reset the session */
2140                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) {
2141                         section = "reset session";
2142                         status = nfs4_reset_session(clp);
2143                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
2144                                 continue;
2145                         if (status < 0)
2146                                 goto out_error;
2147                 }
2148
2149                 /* Send BIND_CONN_TO_SESSION */
2150                 if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2151                                 &clp->cl_state)) {
2152                         section = "bind conn to session";
2153                         status = nfs4_bind_conn_to_session(clp);
2154                         if (status < 0)
2155                                 goto out_error;
2156                         continue;
2157                 }
2158
2159                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
2160                         section = "check lease";
2161                         status = nfs4_check_lease(clp);
2162                         if (status < 0)
2163                                 goto out_error;
2164                         continue;
2165                 }
2166
2167                 /* First recover reboot state... */
2168                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
2169                         section = "reclaim reboot";
2170                         status = nfs4_do_reclaim(clp,
2171                                 clp->cl_mvops->reboot_recovery_ops);
2172                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
2173                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
2174                                 continue;
2175                         nfs4_state_end_reclaim_reboot(clp);
2176                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
2177                                 continue;
2178                         if (status < 0)
2179                                 goto out_error;
2180                 }
2181
2182                 /* Now recover expired state... */
2183                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
2184                         section = "reclaim nograce";
2185                         status = nfs4_do_reclaim(clp,
2186                                 clp->cl_mvops->nograce_recovery_ops);
2187                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
2188                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
2189                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
2190                                 continue;
2191                         if (status < 0)
2192                                 goto out_error;
2193                 }
2194
2195                 nfs4_end_drain_session(clp);
2196                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
2197                         nfs_client_return_marked_delegations(clp);
2198                         continue;
2199                 }
2200
2201                 nfs4_clear_state_manager_bit(clp);
2202                 /* Did we race with an attempt to give us more work? */
2203                 if (clp->cl_state == 0)
2204                         break;
2205                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
2206                         break;
2207         } while (atomic_read(&clp->cl_count) > 1);
2208         return;
2209 out_error:
2210         if (strlen(section))
2211                 section_sep = ": ";
2212         pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s"
2213                         " with error %d\n", section_sep, section,
2214                         clp->cl_hostname, -status);
2215         ssleep(1);
2216         nfs4_end_drain_session(clp);
2217         nfs4_clear_state_manager_bit(clp);
2218 }
2219
2220 static int nfs4_run_state_manager(void *ptr)
2221 {
2222         struct nfs_client *clp = ptr;
2223
2224         allow_signal(SIGKILL);
2225         nfs4_state_manager(clp);
2226         nfs_put_client(clp);
2227         module_put_and_exit(0);
2228         return 0;
2229 }
2230
2231 /*
2232  * Local variables:
2233  *  c-basic-offset: 8
2234  * End:
2235  */