NFSv4: Rate limit the state manager for lock reclaim warning messages
[firefly-linux-kernel-4.4.55.git] / 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 "nfs4_fs.h"
55 #include "callback.h"
56 #include "delegation.h"
57 #include "internal.h"
58 #include "pnfs.h"
59
60 #define OPENOWNER_POOL_SIZE     8
61
62 const nfs4_stateid zero_stateid;
63
64 static LIST_HEAD(nfs4_clientid_list);
65
66 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
67 {
68         struct nfs4_setclientid_res clid = {
69                 .clientid = clp->cl_clientid,
70                 .confirm = clp->cl_confirm,
71         };
72         unsigned short port;
73         int status;
74
75         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
76                 goto do_confirm;
77         port = nfs_callback_tcpport;
78         if (clp->cl_addr.ss_family == AF_INET6)
79                 port = nfs_callback_tcpport6;
80
81         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
82         if (status != 0)
83                 goto out;
84         clp->cl_clientid = clid.clientid;
85         clp->cl_confirm = clid.confirm;
86         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
87 do_confirm:
88         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
89         if (status != 0)
90                 goto out;
91         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
92         nfs4_schedule_state_renewal(clp);
93 out:
94         return status;
95 }
96
97 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
98 {
99         struct rpc_cred *cred = NULL;
100
101         if (clp->cl_machine_cred != NULL)
102                 cred = get_rpccred(clp->cl_machine_cred);
103         return cred;
104 }
105
106 static void nfs4_clear_machine_cred(struct nfs_client *clp)
107 {
108         struct rpc_cred *cred;
109
110         spin_lock(&clp->cl_lock);
111         cred = clp->cl_machine_cred;
112         clp->cl_machine_cred = NULL;
113         spin_unlock(&clp->cl_lock);
114         if (cred != NULL)
115                 put_rpccred(cred);
116 }
117
118 static struct rpc_cred *
119 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
120 {
121         struct rpc_cred *cred = NULL;
122         struct nfs4_state_owner *sp;
123         struct rb_node *pos;
124
125         for (pos = rb_first(&server->state_owners);
126              pos != NULL;
127              pos = rb_next(pos)) {
128                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
129                 if (list_empty(&sp->so_states))
130                         continue;
131                 cred = get_rpccred(sp->so_cred);
132                 break;
133         }
134         return cred;
135 }
136
137 /**
138  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
139  * @clp: client state handle
140  *
141  * Returns an rpc_cred with reference count bumped, or NULL.
142  * Caller must hold clp->cl_lock.
143  */
144 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
145 {
146         struct rpc_cred *cred = NULL;
147         struct nfs_server *server;
148
149         rcu_read_lock();
150         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
151                 cred = nfs4_get_renew_cred_server_locked(server);
152                 if (cred != NULL)
153                         break;
154         }
155         rcu_read_unlock();
156         return cred;
157 }
158
159 #if defined(CONFIG_NFS_V4_1)
160
161 static int nfs41_setup_state_renewal(struct nfs_client *clp)
162 {
163         int status;
164         struct nfs_fsinfo fsinfo;
165
166         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
167                 nfs4_schedule_state_renewal(clp);
168                 return 0;
169         }
170
171         status = nfs4_proc_get_lease_time(clp, &fsinfo);
172         if (status == 0) {
173                 /* Update lease time and schedule renewal */
174                 spin_lock(&clp->cl_lock);
175                 clp->cl_lease_time = fsinfo.lease_time * HZ;
176                 clp->cl_last_renewal = jiffies;
177                 spin_unlock(&clp->cl_lock);
178
179                 nfs4_schedule_state_renewal(clp);
180         }
181
182         return status;
183 }
184
185 /*
186  * Back channel returns NFS4ERR_DELAY for new requests when
187  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
188  * is ended.
189  */
190 static void nfs4_end_drain_session(struct nfs_client *clp)
191 {
192         struct nfs4_session *ses = clp->cl_session;
193         struct nfs4_slot_table *tbl;
194         int max_slots;
195
196         if (ses == NULL)
197                 return;
198         tbl = &ses->fc_slot_table;
199         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
200                 spin_lock(&tbl->slot_tbl_lock);
201                 max_slots = tbl->max_slots;
202                 while (max_slots--) {
203                         if (rpc_wake_up_first(&tbl->slot_tbl_waitq,
204                                                 nfs4_set_task_privileged,
205                                                 NULL) == NULL)
206                                 break;
207                 }
208                 spin_unlock(&tbl->slot_tbl_lock);
209         }
210 }
211
212 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
213 {
214         spin_lock(&tbl->slot_tbl_lock);
215         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
216                 INIT_COMPLETION(tbl->complete);
217                 spin_unlock(&tbl->slot_tbl_lock);
218                 return wait_for_completion_interruptible(&tbl->complete);
219         }
220         spin_unlock(&tbl->slot_tbl_lock);
221         return 0;
222 }
223
224 static int nfs4_begin_drain_session(struct nfs_client *clp)
225 {
226         struct nfs4_session *ses = clp->cl_session;
227         int ret = 0;
228
229         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
230         /* back channel */
231         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
232         if (ret)
233                 return ret;
234         /* fore channel */
235         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
236 }
237
238 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
239 {
240         int status;
241
242         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
243                 goto do_confirm;
244         nfs4_begin_drain_session(clp);
245         status = nfs4_proc_exchange_id(clp, cred);
246         if (status != 0)
247                 goto out;
248         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
249 do_confirm:
250         status = nfs4_proc_create_session(clp);
251         if (status != 0)
252                 goto out;
253         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
254         nfs41_setup_state_renewal(clp);
255         nfs_mark_client_ready(clp, NFS_CS_READY);
256 out:
257         return status;
258 }
259
260 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
261 {
262         struct rpc_cred *cred;
263
264         spin_lock(&clp->cl_lock);
265         cred = nfs4_get_machine_cred_locked(clp);
266         spin_unlock(&clp->cl_lock);
267         return cred;
268 }
269
270 #endif /* CONFIG_NFS_V4_1 */
271
272 static struct rpc_cred *
273 nfs4_get_setclientid_cred_server(struct nfs_server *server)
274 {
275         struct nfs_client *clp = server->nfs_client;
276         struct rpc_cred *cred = NULL;
277         struct nfs4_state_owner *sp;
278         struct rb_node *pos;
279
280         spin_lock(&clp->cl_lock);
281         pos = rb_first(&server->state_owners);
282         if (pos != NULL) {
283                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
284                 cred = get_rpccred(sp->so_cred);
285         }
286         spin_unlock(&clp->cl_lock);
287         return cred;
288 }
289
290 /**
291  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
292  * @clp: client state handle
293  *
294  * Returns an rpc_cred with reference count bumped, or NULL.
295  */
296 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
297 {
298         struct nfs_server *server;
299         struct rpc_cred *cred;
300
301         spin_lock(&clp->cl_lock);
302         cred = nfs4_get_machine_cred_locked(clp);
303         spin_unlock(&clp->cl_lock);
304         if (cred != NULL)
305                 goto out;
306
307         rcu_read_lock();
308         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
309                 cred = nfs4_get_setclientid_cred_server(server);
310                 if (cred != NULL)
311                         break;
312         }
313         rcu_read_unlock();
314
315 out:
316         return cred;
317 }
318
319 static struct nfs4_state_owner *
320 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
321 {
322         struct rb_node **p = &server->state_owners.rb_node,
323                        *parent = NULL;
324         struct nfs4_state_owner *sp;
325
326         while (*p != NULL) {
327                 parent = *p;
328                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
329
330                 if (cred < sp->so_cred)
331                         p = &parent->rb_left;
332                 else if (cred > sp->so_cred)
333                         p = &parent->rb_right;
334                 else {
335                         if (!list_empty(&sp->so_lru))
336                                 list_del_init(&sp->so_lru);
337                         atomic_inc(&sp->so_count);
338                         return sp;
339                 }
340         }
341         return NULL;
342 }
343
344 static struct nfs4_state_owner *
345 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
346 {
347         struct nfs_server *server = new->so_server;
348         struct rb_node **p = &server->state_owners.rb_node,
349                        *parent = NULL;
350         struct nfs4_state_owner *sp;
351         int err;
352
353         while (*p != NULL) {
354                 parent = *p;
355                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
356
357                 if (new->so_cred < sp->so_cred)
358                         p = &parent->rb_left;
359                 else if (new->so_cred > sp->so_cred)
360                         p = &parent->rb_right;
361                 else {
362                         if (!list_empty(&sp->so_lru))
363                                 list_del_init(&sp->so_lru);
364                         atomic_inc(&sp->so_count);
365                         return sp;
366                 }
367         }
368         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
369         if (err)
370                 return ERR_PTR(err);
371         rb_link_node(&new->so_server_node, parent, p);
372         rb_insert_color(&new->so_server_node, &server->state_owners);
373         return new;
374 }
375
376 static void
377 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
378 {
379         struct nfs_server *server = sp->so_server;
380
381         if (!RB_EMPTY_NODE(&sp->so_server_node))
382                 rb_erase(&sp->so_server_node, &server->state_owners);
383         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
384 }
385
386 static void
387 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
388 {
389         sc->flags = 0;
390         sc->counter = 0;
391         spin_lock_init(&sc->lock);
392         INIT_LIST_HEAD(&sc->list);
393         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
394 }
395
396 static void
397 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
398 {
399         rpc_destroy_wait_queue(&sc->wait);
400 }
401
402 /*
403  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
404  * create a new state_owner.
405  *
406  */
407 static struct nfs4_state_owner *
408 nfs4_alloc_state_owner(struct nfs_server *server,
409                 struct rpc_cred *cred,
410                 gfp_t gfp_flags)
411 {
412         struct nfs4_state_owner *sp;
413
414         sp = kzalloc(sizeof(*sp), gfp_flags);
415         if (!sp)
416                 return NULL;
417         sp->so_server = server;
418         sp->so_cred = get_rpccred(cred);
419         spin_lock_init(&sp->so_lock);
420         INIT_LIST_HEAD(&sp->so_states);
421         nfs4_init_seqid_counter(&sp->so_seqid);
422         atomic_set(&sp->so_count, 1);
423         INIT_LIST_HEAD(&sp->so_lru);
424         return sp;
425 }
426
427 static void
428 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
429 {
430         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
431                 struct nfs_server *server = sp->so_server;
432                 struct nfs_client *clp = server->nfs_client;
433
434                 spin_lock(&clp->cl_lock);
435                 rb_erase(&sp->so_server_node, &server->state_owners);
436                 RB_CLEAR_NODE(&sp->so_server_node);
437                 spin_unlock(&clp->cl_lock);
438         }
439 }
440
441 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
442 {
443         nfs4_destroy_seqid_counter(&sp->so_seqid);
444         put_rpccred(sp->so_cred);
445         kfree(sp);
446 }
447
448 static void nfs4_gc_state_owners(struct nfs_server *server)
449 {
450         struct nfs_client *clp = server->nfs_client;
451         struct nfs4_state_owner *sp, *tmp;
452         unsigned long time_min, time_max;
453         LIST_HEAD(doomed);
454
455         spin_lock(&clp->cl_lock);
456         time_max = jiffies;
457         time_min = (long)time_max - (long)clp->cl_lease_time;
458         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
459                 /* NB: LRU is sorted so that oldest is at the head */
460                 if (time_in_range(sp->so_expires, time_min, time_max))
461                         break;
462                 list_move(&sp->so_lru, &doomed);
463                 nfs4_remove_state_owner_locked(sp);
464         }
465         spin_unlock(&clp->cl_lock);
466
467         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
468                 list_del(&sp->so_lru);
469                 nfs4_free_state_owner(sp);
470         }
471 }
472
473 /**
474  * nfs4_get_state_owner - Look up a state owner given a credential
475  * @server: nfs_server to search
476  * @cred: RPC credential to match
477  *
478  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
479  */
480 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
481                                               struct rpc_cred *cred,
482                                               gfp_t gfp_flags)
483 {
484         struct nfs_client *clp = server->nfs_client;
485         struct nfs4_state_owner *sp, *new;
486
487         spin_lock(&clp->cl_lock);
488         sp = nfs4_find_state_owner_locked(server, cred);
489         spin_unlock(&clp->cl_lock);
490         if (sp != NULL)
491                 goto out;
492         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
493         if (new == NULL)
494                 goto out;
495         do {
496                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
497                         break;
498                 spin_lock(&clp->cl_lock);
499                 sp = nfs4_insert_state_owner_locked(new);
500                 spin_unlock(&clp->cl_lock);
501         } while (sp == ERR_PTR(-EAGAIN));
502         if (sp != new)
503                 nfs4_free_state_owner(new);
504 out:
505         nfs4_gc_state_owners(server);
506         return sp;
507 }
508
509 /**
510  * nfs4_put_state_owner - Release a nfs4_state_owner
511  * @sp: state owner data to release
512  */
513 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
514 {
515         struct nfs_server *server = sp->so_server;
516         struct nfs_client *clp = server->nfs_client;
517
518         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
519                 return;
520
521         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
522                 sp->so_expires = jiffies;
523                 list_add_tail(&sp->so_lru, &server->state_owners_lru);
524                 spin_unlock(&clp->cl_lock);
525         } else {
526                 nfs4_remove_state_owner_locked(sp);
527                 spin_unlock(&clp->cl_lock);
528                 nfs4_free_state_owner(sp);
529         }
530 }
531
532 /**
533  * nfs4_purge_state_owners - Release all cached state owners
534  * @server: nfs_server with cached state owners to release
535  *
536  * Called at umount time.  Remaining state owners will be on
537  * the LRU with ref count of zero.
538  */
539 void nfs4_purge_state_owners(struct nfs_server *server)
540 {
541         struct nfs_client *clp = server->nfs_client;
542         struct nfs4_state_owner *sp, *tmp;
543         LIST_HEAD(doomed);
544
545         spin_lock(&clp->cl_lock);
546         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
547                 list_move(&sp->so_lru, &doomed);
548                 nfs4_remove_state_owner_locked(sp);
549         }
550         spin_unlock(&clp->cl_lock);
551
552         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
553                 list_del(&sp->so_lru);
554                 nfs4_free_state_owner(sp);
555         }
556 }
557
558 static struct nfs4_state *
559 nfs4_alloc_open_state(void)
560 {
561         struct nfs4_state *state;
562
563         state = kzalloc(sizeof(*state), GFP_NOFS);
564         if (!state)
565                 return NULL;
566         atomic_set(&state->count, 1);
567         INIT_LIST_HEAD(&state->lock_states);
568         spin_lock_init(&state->state_lock);
569         seqlock_init(&state->seqlock);
570         return state;
571 }
572
573 void
574 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
575 {
576         if (state->state == fmode)
577                 return;
578         /* NB! List reordering - see the reclaim code for why.  */
579         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
580                 if (fmode & FMODE_WRITE)
581                         list_move(&state->open_states, &state->owner->so_states);
582                 else
583                         list_move_tail(&state->open_states, &state->owner->so_states);
584         }
585         state->state = fmode;
586 }
587
588 static struct nfs4_state *
589 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
590 {
591         struct nfs_inode *nfsi = NFS_I(inode);
592         struct nfs4_state *state;
593
594         list_for_each_entry(state, &nfsi->open_states, inode_states) {
595                 if (state->owner != owner)
596                         continue;
597                 if (atomic_inc_not_zero(&state->count))
598                         return state;
599         }
600         return NULL;
601 }
602
603 static void
604 nfs4_free_open_state(struct nfs4_state *state)
605 {
606         kfree(state);
607 }
608
609 struct nfs4_state *
610 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
611 {
612         struct nfs4_state *state, *new;
613         struct nfs_inode *nfsi = NFS_I(inode);
614
615         spin_lock(&inode->i_lock);
616         state = __nfs4_find_state_byowner(inode, owner);
617         spin_unlock(&inode->i_lock);
618         if (state)
619                 goto out;
620         new = nfs4_alloc_open_state();
621         spin_lock(&owner->so_lock);
622         spin_lock(&inode->i_lock);
623         state = __nfs4_find_state_byowner(inode, owner);
624         if (state == NULL && new != NULL) {
625                 state = new;
626                 state->owner = owner;
627                 atomic_inc(&owner->so_count);
628                 list_add(&state->inode_states, &nfsi->open_states);
629                 ihold(inode);
630                 state->inode = inode;
631                 spin_unlock(&inode->i_lock);
632                 /* Note: The reclaim code dictates that we add stateless
633                  * and read-only stateids to the end of the list */
634                 list_add_tail(&state->open_states, &owner->so_states);
635                 spin_unlock(&owner->so_lock);
636         } else {
637                 spin_unlock(&inode->i_lock);
638                 spin_unlock(&owner->so_lock);
639                 if (new)
640                         nfs4_free_open_state(new);
641         }
642 out:
643         return state;
644 }
645
646 void nfs4_put_open_state(struct nfs4_state *state)
647 {
648         struct inode *inode = state->inode;
649         struct nfs4_state_owner *owner = state->owner;
650
651         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
652                 return;
653         spin_lock(&inode->i_lock);
654         list_del(&state->inode_states);
655         list_del(&state->open_states);
656         spin_unlock(&inode->i_lock);
657         spin_unlock(&owner->so_lock);
658         iput(inode);
659         nfs4_free_open_state(state);
660         nfs4_put_state_owner(owner);
661 }
662
663 /*
664  * Close the current file.
665  */
666 static void __nfs4_close(struct nfs4_state *state,
667                 fmode_t fmode, gfp_t gfp_mask, int wait)
668 {
669         struct nfs4_state_owner *owner = state->owner;
670         int call_close = 0;
671         fmode_t newstate;
672
673         atomic_inc(&owner->so_count);
674         /* Protect against nfs4_find_state() */
675         spin_lock(&owner->so_lock);
676         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
677                 case FMODE_READ:
678                         state->n_rdonly--;
679                         break;
680                 case FMODE_WRITE:
681                         state->n_wronly--;
682                         break;
683                 case FMODE_READ|FMODE_WRITE:
684                         state->n_rdwr--;
685         }
686         newstate = FMODE_READ|FMODE_WRITE;
687         if (state->n_rdwr == 0) {
688                 if (state->n_rdonly == 0) {
689                         newstate &= ~FMODE_READ;
690                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
691                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
692                 }
693                 if (state->n_wronly == 0) {
694                         newstate &= ~FMODE_WRITE;
695                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
696                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
697                 }
698                 if (newstate == 0)
699                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
700         }
701         nfs4_state_set_mode_locked(state, newstate);
702         spin_unlock(&owner->so_lock);
703
704         if (!call_close) {
705                 nfs4_put_open_state(state);
706                 nfs4_put_state_owner(owner);
707         } else {
708                 bool roc = pnfs_roc(state->inode);
709
710                 nfs4_do_close(state, gfp_mask, wait, roc);
711         }
712 }
713
714 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
715 {
716         __nfs4_close(state, fmode, GFP_NOFS, 0);
717 }
718
719 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
720 {
721         __nfs4_close(state, fmode, GFP_KERNEL, 1);
722 }
723
724 /*
725  * Search the state->lock_states for an existing lock_owner
726  * that is compatible with current->files
727  */
728 static struct nfs4_lock_state *
729 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
730 {
731         struct nfs4_lock_state *pos;
732         list_for_each_entry(pos, &state->lock_states, ls_locks) {
733                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
734                         continue;
735                 switch (pos->ls_owner.lo_type) {
736                 case NFS4_POSIX_LOCK_TYPE:
737                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
738                                 continue;
739                         break;
740                 case NFS4_FLOCK_LOCK_TYPE:
741                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
742                                 continue;
743                 }
744                 atomic_inc(&pos->ls_count);
745                 return pos;
746         }
747         return NULL;
748 }
749
750 /*
751  * Return a compatible lock_state. If no initialized lock_state structure
752  * exists, return an uninitialized one.
753  *
754  */
755 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)
756 {
757         struct nfs4_lock_state *lsp;
758         struct nfs_server *server = state->owner->so_server;
759
760         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
761         if (lsp == NULL)
762                 return NULL;
763         nfs4_init_seqid_counter(&lsp->ls_seqid);
764         atomic_set(&lsp->ls_count, 1);
765         lsp->ls_state = state;
766         lsp->ls_owner.lo_type = type;
767         switch (lsp->ls_owner.lo_type) {
768         case NFS4_FLOCK_LOCK_TYPE:
769                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
770                 break;
771         case NFS4_POSIX_LOCK_TYPE:
772                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
773                 break;
774         default:
775                 goto out_free;
776         }
777         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
778         if (lsp->ls_seqid.owner_id < 0)
779                 goto out_free;
780         INIT_LIST_HEAD(&lsp->ls_locks);
781         return lsp;
782 out_free:
783         kfree(lsp);
784         return NULL;
785 }
786
787 void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
788 {
789         struct nfs_server *server = lsp->ls_state->owner->so_server;
790
791         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
792         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
793         kfree(lsp);
794 }
795
796 /*
797  * Return a compatible lock_state. If no initialized lock_state structure
798  * exists, return an uninitialized one.
799  *
800  */
801 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
802 {
803         struct nfs4_lock_state *lsp, *new = NULL;
804         
805         for(;;) {
806                 spin_lock(&state->state_lock);
807                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
808                 if (lsp != NULL)
809                         break;
810                 if (new != NULL) {
811                         list_add(&new->ls_locks, &state->lock_states);
812                         set_bit(LK_STATE_IN_USE, &state->flags);
813                         lsp = new;
814                         new = NULL;
815                         break;
816                 }
817                 spin_unlock(&state->state_lock);
818                 new = nfs4_alloc_lock_state(state, owner, pid, type);
819                 if (new == NULL)
820                         return NULL;
821         }
822         spin_unlock(&state->state_lock);
823         if (new != NULL)
824                 nfs4_free_lock_state(new);
825         return lsp;
826 }
827
828 /*
829  * Release reference to lock_state, and free it if we see that
830  * it is no longer in use
831  */
832 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
833 {
834         struct nfs4_state *state;
835
836         if (lsp == NULL)
837                 return;
838         state = lsp->ls_state;
839         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
840                 return;
841         list_del(&lsp->ls_locks);
842         if (list_empty(&state->lock_states))
843                 clear_bit(LK_STATE_IN_USE, &state->flags);
844         spin_unlock(&state->state_lock);
845         if (lsp->ls_flags & NFS_LOCK_INITIALIZED) {
846                 if (nfs4_release_lockowner(lsp) == 0)
847                         return;
848         }
849         nfs4_free_lock_state(lsp);
850 }
851
852 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
853 {
854         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
855
856         dst->fl_u.nfs4_fl.owner = lsp;
857         atomic_inc(&lsp->ls_count);
858 }
859
860 static void nfs4_fl_release_lock(struct file_lock *fl)
861 {
862         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
863 }
864
865 static const struct file_lock_operations nfs4_fl_lock_ops = {
866         .fl_copy_lock = nfs4_fl_copy_lock,
867         .fl_release_private = nfs4_fl_release_lock,
868 };
869
870 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
871 {
872         struct nfs4_lock_state *lsp;
873
874         if (fl->fl_ops != NULL)
875                 return 0;
876         if (fl->fl_flags & FL_POSIX)
877                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
878         else if (fl->fl_flags & FL_FLOCK)
879                 lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
880                                 NFS4_FLOCK_LOCK_TYPE);
881         else
882                 return -EINVAL;
883         if (lsp == NULL)
884                 return -ENOMEM;
885         fl->fl_u.nfs4_fl.owner = lsp;
886         fl->fl_ops = &nfs4_fl_lock_ops;
887         return 0;
888 }
889
890 static bool nfs4_copy_lock_stateid(nfs4_stateid *dst, struct nfs4_state *state,
891                 fl_owner_t fl_owner, pid_t fl_pid)
892 {
893         struct nfs4_lock_state *lsp;
894         bool ret = false;
895
896         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
897                 goto out;
898
899         spin_lock(&state->state_lock);
900         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
901         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0) {
902                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
903                 ret = true;
904         }
905         spin_unlock(&state->state_lock);
906         nfs4_put_lock_state(lsp);
907 out:
908         return ret;
909 }
910
911 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
912 {
913         int seq;
914
915         do {
916                 seq = read_seqbegin(&state->seqlock);
917                 nfs4_stateid_copy(dst, &state->stateid);
918         } while (read_seqretry(&state->seqlock, seq));
919 }
920
921 /*
922  * Byte-range lock aware utility to initialize the stateid of read/write
923  * requests.
924  */
925 void nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
926                 fmode_t fmode, fl_owner_t fl_owner, pid_t fl_pid)
927 {
928         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
929                 return;
930         if (nfs4_copy_lock_stateid(dst, state, fl_owner, fl_pid))
931                 return;
932         nfs4_copy_open_stateid(dst, state);
933 }
934
935 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
936 {
937         struct nfs_seqid *new;
938
939         new = kmalloc(sizeof(*new), gfp_mask);
940         if (new != NULL) {
941                 new->sequence = counter;
942                 INIT_LIST_HEAD(&new->list);
943                 new->task = NULL;
944         }
945         return new;
946 }
947
948 void nfs_release_seqid(struct nfs_seqid *seqid)
949 {
950         struct nfs_seqid_counter *sequence;
951
952         if (list_empty(&seqid->list))
953                 return;
954         sequence = seqid->sequence;
955         spin_lock(&sequence->lock);
956         list_del_init(&seqid->list);
957         if (!list_empty(&sequence->list)) {
958                 struct nfs_seqid *next;
959
960                 next = list_first_entry(&sequence->list,
961                                 struct nfs_seqid, list);
962                 rpc_wake_up_queued_task(&sequence->wait, next->task);
963         }
964         spin_unlock(&sequence->lock);
965 }
966
967 void nfs_free_seqid(struct nfs_seqid *seqid)
968 {
969         nfs_release_seqid(seqid);
970         kfree(seqid);
971 }
972
973 /*
974  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
975  * failed with a seqid incrementing error -
976  * see comments nfs_fs.h:seqid_mutating_error()
977  */
978 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
979 {
980         BUG_ON(list_first_entry(&seqid->sequence->list, struct nfs_seqid, list) != seqid);
981         switch (status) {
982                 case 0:
983                         break;
984                 case -NFS4ERR_BAD_SEQID:
985                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
986                                 return;
987                         pr_warn_ratelimited("NFS: v4 server returned a bad"
988                                         " sequence-id error on an"
989                                         " unconfirmed sequence %p!\n",
990                                         seqid->sequence);
991                 case -NFS4ERR_STALE_CLIENTID:
992                 case -NFS4ERR_STALE_STATEID:
993                 case -NFS4ERR_BAD_STATEID:
994                 case -NFS4ERR_BADXDR:
995                 case -NFS4ERR_RESOURCE:
996                 case -NFS4ERR_NOFILEHANDLE:
997                         /* Non-seqid mutating errors */
998                         return;
999         };
1000         /*
1001          * Note: no locking needed as we are guaranteed to be first
1002          * on the sequence list
1003          */
1004         seqid->sequence->counter++;
1005 }
1006
1007 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1008 {
1009         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1010                                         struct nfs4_state_owner, so_seqid);
1011         struct nfs_server *server = sp->so_server;
1012
1013         if (status == -NFS4ERR_BAD_SEQID)
1014                 nfs4_drop_state_owner(sp);
1015         if (!nfs4_has_session(server->nfs_client))
1016                 nfs_increment_seqid(status, seqid);
1017 }
1018
1019 /*
1020  * Increment the seqid if the LOCK/LOCKU succeeded, or
1021  * failed with a seqid incrementing error -
1022  * see comments nfs_fs.h:seqid_mutating_error()
1023  */
1024 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1025 {
1026         nfs_increment_seqid(status, seqid);
1027 }
1028
1029 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1030 {
1031         struct nfs_seqid_counter *sequence = seqid->sequence;
1032         int status = 0;
1033
1034         spin_lock(&sequence->lock);
1035         seqid->task = task;
1036         if (list_empty(&seqid->list))
1037                 list_add_tail(&seqid->list, &sequence->list);
1038         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1039                 goto unlock;
1040         rpc_sleep_on(&sequence->wait, task, NULL);
1041         status = -EAGAIN;
1042 unlock:
1043         spin_unlock(&sequence->lock);
1044         return status;
1045 }
1046
1047 static int nfs4_run_state_manager(void *);
1048
1049 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1050 {
1051         smp_mb__before_clear_bit();
1052         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1053         smp_mb__after_clear_bit();
1054         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1055         rpc_wake_up(&clp->cl_rpcwaitq);
1056 }
1057
1058 /*
1059  * Schedule the nfs_client asynchronous state management routine
1060  */
1061 void nfs4_schedule_state_manager(struct nfs_client *clp)
1062 {
1063         struct task_struct *task;
1064         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1065
1066         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1067                 return;
1068         __module_get(THIS_MODULE);
1069         atomic_inc(&clp->cl_count);
1070
1071         /* The rcu_read_lock() is not strictly necessary, as the state
1072          * manager is the only thread that ever changes the rpc_xprt
1073          * after it's initialized.  At this point, we're single threaded. */
1074         rcu_read_lock();
1075         snprintf(buf, sizeof(buf), "%s-manager",
1076                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1077         rcu_read_unlock();
1078         task = kthread_run(nfs4_run_state_manager, clp, buf);
1079         if (IS_ERR(task)) {
1080                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1081                         __func__, PTR_ERR(task));
1082                 nfs4_clear_state_manager_bit(clp);
1083                 nfs_put_client(clp);
1084                 module_put(THIS_MODULE);
1085         }
1086 }
1087
1088 /*
1089  * Schedule a lease recovery attempt
1090  */
1091 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1092 {
1093         if (!clp)
1094                 return;
1095         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1096                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1097         nfs4_schedule_state_manager(clp);
1098 }
1099 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1100
1101 /*
1102  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1103  * @clp: client to process
1104  *
1105  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1106  * resend of the SETCLIENTID and hence re-establish the
1107  * callback channel. Then return all existing delegations.
1108  */
1109 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1110 {
1111         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1112         nfs_expire_all_delegations(clp);
1113 }
1114
1115 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1116 {
1117         nfs40_handle_cb_pathdown(clp);
1118         nfs4_schedule_state_manager(clp);
1119 }
1120
1121 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1122 {
1123
1124         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1125         /* Don't recover state that expired before the reboot */
1126         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1127                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1128                 return 0;
1129         }
1130         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1131         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1132         return 1;
1133 }
1134
1135 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1136 {
1137         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1138         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1139         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1140         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1141         return 1;
1142 }
1143
1144 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1145 {
1146         struct nfs_client *clp = server->nfs_client;
1147
1148         nfs4_state_mark_reclaim_nograce(clp, state);
1149         nfs4_schedule_state_manager(clp);
1150 }
1151 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1152
1153 void nfs_inode_find_state_and_recover(struct inode *inode,
1154                 const nfs4_stateid *stateid)
1155 {
1156         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1157         struct nfs_inode *nfsi = NFS_I(inode);
1158         struct nfs_open_context *ctx;
1159         struct nfs4_state *state;
1160         bool found = false;
1161
1162         spin_lock(&inode->i_lock);
1163         list_for_each_entry(ctx, &nfsi->open_files, list) {
1164                 state = ctx->state;
1165                 if (state == NULL)
1166                         continue;
1167                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1168                         continue;
1169                 if (!nfs4_stateid_match(&state->stateid, stateid))
1170                         continue;
1171                 nfs4_state_mark_reclaim_nograce(clp, state);
1172                 found = true;
1173         }
1174         spin_unlock(&inode->i_lock);
1175         if (found)
1176                 nfs4_schedule_state_manager(clp);
1177 }
1178
1179
1180 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1181 {
1182         struct inode *inode = state->inode;
1183         struct nfs_inode *nfsi = NFS_I(inode);
1184         struct file_lock *fl;
1185         int status = 0;
1186
1187         if (inode->i_flock == NULL)
1188                 return 0;
1189
1190         /* Guard against delegation returns and new lock/unlock calls */
1191         down_write(&nfsi->rwsem);
1192         /* Protect inode->i_flock using the BKL */
1193         lock_flocks();
1194         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1195                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1196                         continue;
1197                 if (nfs_file_open_context(fl->fl_file)->state != state)
1198                         continue;
1199                 unlock_flocks();
1200                 status = ops->recover_lock(state, fl);
1201                 switch (status) {
1202                         case 0:
1203                                 break;
1204                         case -ESTALE:
1205                         case -NFS4ERR_ADMIN_REVOKED:
1206                         case -NFS4ERR_STALE_STATEID:
1207                         case -NFS4ERR_BAD_STATEID:
1208                         case -NFS4ERR_EXPIRED:
1209                         case -NFS4ERR_NO_GRACE:
1210                         case -NFS4ERR_STALE_CLIENTID:
1211                         case -NFS4ERR_BADSESSION:
1212                         case -NFS4ERR_BADSLOT:
1213                         case -NFS4ERR_BAD_HIGH_SLOT:
1214                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1215                                 goto out;
1216                         default:
1217                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1218                                         "Zeroing state\n", __func__, status);
1219                         case -ENOMEM:
1220                         case -NFS4ERR_DENIED:
1221                         case -NFS4ERR_RECLAIM_BAD:
1222                         case -NFS4ERR_RECLAIM_CONFLICT:
1223                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1224                                 status = 0;
1225                 }
1226                 lock_flocks();
1227         }
1228         unlock_flocks();
1229 out:
1230         up_write(&nfsi->rwsem);
1231         return status;
1232 }
1233
1234 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1235 {
1236         struct nfs4_state *state;
1237         struct nfs4_lock_state *lock;
1238         int status = 0;
1239
1240         /* Note: we rely on the sp->so_states list being ordered 
1241          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1242          * states first.
1243          * This is needed to ensure that the server won't give us any
1244          * read delegations that we have to return if, say, we are
1245          * recovering after a network partition or a reboot from a
1246          * server that doesn't support a grace period.
1247          */
1248 restart:
1249         spin_lock(&sp->so_lock);
1250         list_for_each_entry(state, &sp->so_states, open_states) {
1251                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1252                         continue;
1253                 if (state->state == 0)
1254                         continue;
1255                 atomic_inc(&state->count);
1256                 spin_unlock(&sp->so_lock);
1257                 status = ops->recover_open(sp, state);
1258                 if (status >= 0) {
1259                         status = nfs4_reclaim_locks(state, ops);
1260                         if (status >= 0) {
1261                                 spin_lock(&state->state_lock);
1262                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1263                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1264                                                 pr_warn_ratelimited("NFS: "
1265                                                         "%s: Lock reclaim "
1266                                                         "failed!\n", __func__);
1267                                 }
1268                                 spin_unlock(&state->state_lock);
1269                                 nfs4_put_open_state(state);
1270                                 goto restart;
1271                         }
1272                 }
1273                 switch (status) {
1274                         default:
1275                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1276                                         "Zeroing state\n", __func__, status);
1277                         case -ENOENT:
1278                         case -ENOMEM:
1279                         case -ESTALE:
1280                                 /*
1281                                  * Open state on this file cannot be recovered
1282                                  * All we can do is revert to using the zero stateid.
1283                                  */
1284                                 memset(&state->stateid, 0,
1285                                         sizeof(state->stateid));
1286                                 /* Mark the file as being 'closed' */
1287                                 state->state = 0;
1288                                 break;
1289                         case -EKEYEXPIRED:
1290                                 /*
1291                                  * User RPCSEC_GSS context has expired.
1292                                  * We cannot recover this stateid now, so
1293                                  * skip it and allow recovery thread to
1294                                  * proceed.
1295                                  */
1296                                 break;
1297                         case -NFS4ERR_ADMIN_REVOKED:
1298                         case -NFS4ERR_STALE_STATEID:
1299                         case -NFS4ERR_BAD_STATEID:
1300                         case -NFS4ERR_RECLAIM_BAD:
1301                         case -NFS4ERR_RECLAIM_CONFLICT:
1302                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1303                                 break;
1304                         case -NFS4ERR_EXPIRED:
1305                         case -NFS4ERR_NO_GRACE:
1306                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1307                         case -NFS4ERR_STALE_CLIENTID:
1308                         case -NFS4ERR_BADSESSION:
1309                         case -NFS4ERR_BADSLOT:
1310                         case -NFS4ERR_BAD_HIGH_SLOT:
1311                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1312                                 goto out_err;
1313                 }
1314                 nfs4_put_open_state(state);
1315                 goto restart;
1316         }
1317         spin_unlock(&sp->so_lock);
1318         return 0;
1319 out_err:
1320         nfs4_put_open_state(state);
1321         return status;
1322 }
1323
1324 static void nfs4_clear_open_state(struct nfs4_state *state)
1325 {
1326         struct nfs4_lock_state *lock;
1327
1328         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1329         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1330         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1331         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1332         spin_lock(&state->state_lock);
1333         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1334                 lock->ls_seqid.flags = 0;
1335                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1336         }
1337         spin_unlock(&state->state_lock);
1338 }
1339
1340 static void nfs4_reset_seqids(struct nfs_server *server,
1341         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1342 {
1343         struct nfs_client *clp = server->nfs_client;
1344         struct nfs4_state_owner *sp;
1345         struct rb_node *pos;
1346         struct nfs4_state *state;
1347
1348         spin_lock(&clp->cl_lock);
1349         for (pos = rb_first(&server->state_owners);
1350              pos != NULL;
1351              pos = rb_next(pos)) {
1352                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1353                 sp->so_seqid.flags = 0;
1354                 spin_lock(&sp->so_lock);
1355                 list_for_each_entry(state, &sp->so_states, open_states) {
1356                         if (mark_reclaim(clp, state))
1357                                 nfs4_clear_open_state(state);
1358                 }
1359                 spin_unlock(&sp->so_lock);
1360         }
1361         spin_unlock(&clp->cl_lock);
1362 }
1363
1364 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1365         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1366 {
1367         struct nfs_server *server;
1368
1369         rcu_read_lock();
1370         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1371                 nfs4_reset_seqids(server, mark_reclaim);
1372         rcu_read_unlock();
1373 }
1374
1375 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1376 {
1377         /* Mark all delegations for reclaim */
1378         nfs_delegation_mark_reclaim(clp);
1379         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1380 }
1381
1382 static void nfs4_reclaim_complete(struct nfs_client *clp,
1383                                  const struct nfs4_state_recovery_ops *ops)
1384 {
1385         /* Notify the server we're done reclaiming our state */
1386         if (ops->reclaim_complete)
1387                 (void)ops->reclaim_complete(clp);
1388 }
1389
1390 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1391 {
1392         struct nfs_client *clp = server->nfs_client;
1393         struct nfs4_state_owner *sp;
1394         struct rb_node *pos;
1395         struct nfs4_state *state;
1396
1397         spin_lock(&clp->cl_lock);
1398         for (pos = rb_first(&server->state_owners);
1399              pos != NULL;
1400              pos = rb_next(pos)) {
1401                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1402                 spin_lock(&sp->so_lock);
1403                 list_for_each_entry(state, &sp->so_states, open_states) {
1404                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1405                                                 &state->flags))
1406                                 continue;
1407                         nfs4_state_mark_reclaim_nograce(clp, state);
1408                 }
1409                 spin_unlock(&sp->so_lock);
1410         }
1411         spin_unlock(&clp->cl_lock);
1412 }
1413
1414 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1415 {
1416         struct nfs_server *server;
1417
1418         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1419                 return 0;
1420
1421         rcu_read_lock();
1422         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1423                 nfs4_clear_reclaim_server(server);
1424         rcu_read_unlock();
1425
1426         nfs_delegation_reap_unclaimed(clp);
1427         return 1;
1428 }
1429
1430 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1431 {
1432         if (!nfs4_state_clear_reclaim_reboot(clp))
1433                 return;
1434         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1435 }
1436
1437 static void nfs_delegation_clear_all(struct nfs_client *clp)
1438 {
1439         nfs_delegation_mark_reclaim(clp);
1440         nfs_delegation_reap_unclaimed(clp);
1441 }
1442
1443 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1444 {
1445         nfs_delegation_clear_all(clp);
1446         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1447 }
1448
1449 static void nfs4_warn_keyexpired(const char *s)
1450 {
1451         printk_ratelimited(KERN_WARNING "Error: state manager"
1452                         " encountered RPCSEC_GSS session"
1453                         " expired against NFSv4 server %s.\n",
1454                         s);
1455 }
1456
1457 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1458 {
1459         switch (error) {
1460                 case 0:
1461                         break;
1462                 case -NFS4ERR_CB_PATH_DOWN:
1463                         nfs40_handle_cb_pathdown(clp);
1464                         break;
1465                 case -NFS4ERR_NO_GRACE:
1466                         nfs4_state_end_reclaim_reboot(clp);
1467                         break;
1468                 case -NFS4ERR_STALE_CLIENTID:
1469                 case -NFS4ERR_LEASE_MOVED:
1470                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1471                         nfs4_state_clear_reclaim_reboot(clp);
1472                         nfs4_state_start_reclaim_reboot(clp);
1473                         break;
1474                 case -NFS4ERR_EXPIRED:
1475                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1476                         nfs4_state_start_reclaim_nograce(clp);
1477                         break;
1478                 case -NFS4ERR_BADSESSION:
1479                 case -NFS4ERR_BADSLOT:
1480                 case -NFS4ERR_BAD_HIGH_SLOT:
1481                 case -NFS4ERR_DEADSESSION:
1482                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1483                 case -NFS4ERR_SEQ_FALSE_RETRY:
1484                 case -NFS4ERR_SEQ_MISORDERED:
1485                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1486                         /* Zero session reset errors */
1487                         break;
1488                 case -EKEYEXPIRED:
1489                         /* Nothing we can do */
1490                         nfs4_warn_keyexpired(clp->cl_hostname);
1491                         break;
1492                 default:
1493                         return error;
1494         }
1495         return 0;
1496 }
1497
1498 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1499 {
1500         struct nfs4_state_owner *sp;
1501         struct nfs_server *server;
1502         struct rb_node *pos;
1503         int status = 0;
1504
1505 restart:
1506         rcu_read_lock();
1507         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1508                 nfs4_purge_state_owners(server);
1509                 spin_lock(&clp->cl_lock);
1510                 for (pos = rb_first(&server->state_owners);
1511                      pos != NULL;
1512                      pos = rb_next(pos)) {
1513                         sp = rb_entry(pos,
1514                                 struct nfs4_state_owner, so_server_node);
1515                         if (!test_and_clear_bit(ops->owner_flag_bit,
1516                                                         &sp->so_flags))
1517                                 continue;
1518                         atomic_inc(&sp->so_count);
1519                         spin_unlock(&clp->cl_lock);
1520                         rcu_read_unlock();
1521
1522                         status = nfs4_reclaim_open_state(sp, ops);
1523                         if (status < 0) {
1524                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1525                                 nfs4_put_state_owner(sp);
1526                                 return nfs4_recovery_handle_error(clp, status);
1527                         }
1528
1529                         nfs4_put_state_owner(sp);
1530                         goto restart;
1531                 }
1532                 spin_unlock(&clp->cl_lock);
1533         }
1534         rcu_read_unlock();
1535         return status;
1536 }
1537
1538 static int nfs4_check_lease(struct nfs_client *clp)
1539 {
1540         struct rpc_cred *cred;
1541         const struct nfs4_state_maintenance_ops *ops =
1542                 clp->cl_mvops->state_renewal_ops;
1543         int status;
1544
1545         /* Is the client already known to have an expired lease? */
1546         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1547                 return 0;
1548         spin_lock(&clp->cl_lock);
1549         cred = ops->get_state_renewal_cred_locked(clp);
1550         spin_unlock(&clp->cl_lock);
1551         if (cred == NULL) {
1552                 cred = nfs4_get_setclientid_cred(clp);
1553                 status = -ENOKEY;
1554                 if (cred == NULL)
1555                         goto out;
1556         }
1557         status = ops->renew_lease(clp, cred);
1558         put_rpccred(cred);
1559 out:
1560         return nfs4_recovery_handle_error(clp, status);
1561 }
1562
1563 static int nfs4_reclaim_lease(struct nfs_client *clp)
1564 {
1565         struct rpc_cred *cred;
1566         const struct nfs4_state_recovery_ops *ops =
1567                 clp->cl_mvops->reboot_recovery_ops;
1568         int status = -ENOENT;
1569
1570         cred = ops->get_clid_cred(clp);
1571         if (cred != NULL) {
1572                 status = ops->establish_clid(clp, cred);
1573                 put_rpccred(cred);
1574                 /* Handle case where the user hasn't set up machine creds */
1575                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1576                         nfs4_clear_machine_cred(clp);
1577                         status = -EAGAIN;
1578                 }
1579                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1580                         status = -EPROTONOSUPPORT;
1581         }
1582         return status;
1583 }
1584
1585 #ifdef CONFIG_NFS_V4_1
1586 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1587 {
1588         struct nfs_client *clp = session->clp;
1589
1590         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1591         nfs4_schedule_lease_recovery(clp);
1592 }
1593 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1594
1595 void nfs41_handle_recall_slot(struct nfs_client *clp)
1596 {
1597         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1598         nfs4_schedule_state_manager(clp);
1599 }
1600
1601 static void nfs4_reset_all_state(struct nfs_client *clp)
1602 {
1603         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1604                 clp->cl_boot_time = CURRENT_TIME;
1605                 nfs4_state_start_reclaim_nograce(clp);
1606                 nfs4_schedule_state_manager(clp);
1607         }
1608 }
1609
1610 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1611 {
1612         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1613                 nfs4_state_start_reclaim_reboot(clp);
1614                 nfs4_schedule_state_manager(clp);
1615         }
1616 }
1617
1618 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1619 {
1620         /* Temporary */
1621         nfs4_reset_all_state(clp);
1622 }
1623
1624 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1625 {
1626         /* This will need to handle layouts too */
1627         nfs_expire_all_delegations(clp);
1628 }
1629
1630 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1631 {
1632         nfs_expire_all_delegations(clp);
1633         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1634                 nfs4_schedule_state_manager(clp);
1635 }
1636
1637 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1638 {
1639         if (!flags)
1640                 return;
1641         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1642                 nfs41_handle_server_reboot(clp);
1643         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1644                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1645                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1646                             SEQ4_STATUS_LEASE_MOVED))
1647                 nfs41_handle_state_revoked(clp);
1648         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1649                 nfs41_handle_recallable_state_revoked(clp);
1650         if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1651                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1652                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1653                 nfs41_handle_cb_path_down(clp);
1654 }
1655
1656 static int nfs4_reset_session(struct nfs_client *clp)
1657 {
1658         int status;
1659
1660         nfs4_begin_drain_session(clp);
1661         status = nfs4_proc_destroy_session(clp->cl_session);
1662         if (status && status != -NFS4ERR_BADSESSION &&
1663             status != -NFS4ERR_DEADSESSION) {
1664                 status = nfs4_recovery_handle_error(clp, status);
1665                 goto out;
1666         }
1667
1668         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1669         status = nfs4_proc_create_session(clp);
1670         if (status) {
1671                 status = nfs4_recovery_handle_error(clp, status);
1672                 goto out;
1673         }
1674         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1675         /* create_session negotiated new slot table */
1676         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1677
1678          /* Let the state manager reestablish state */
1679         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1680                 nfs41_setup_state_renewal(clp);
1681 out:
1682         return status;
1683 }
1684
1685 static int nfs4_recall_slot(struct nfs_client *clp)
1686 {
1687         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1688         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1689         struct nfs4_slot *new, *old;
1690         int i;
1691
1692         nfs4_begin_drain_session(clp);
1693         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1694                       GFP_NOFS);
1695         if (!new)
1696                 return -ENOMEM;
1697
1698         spin_lock(&fc_tbl->slot_tbl_lock);
1699         for (i = 0; i < fc_tbl->target_max_slots; i++)
1700                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1701         old = fc_tbl->slots;
1702         fc_tbl->slots = new;
1703         fc_tbl->max_slots = fc_tbl->target_max_slots;
1704         fc_tbl->target_max_slots = 0;
1705         fc_attrs->max_reqs = fc_tbl->max_slots;
1706         spin_unlock(&fc_tbl->slot_tbl_lock);
1707
1708         kfree(old);
1709         nfs4_end_drain_session(clp);
1710         return 0;
1711 }
1712
1713 #else /* CONFIG_NFS_V4_1 */
1714 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1715 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1716 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1717 #endif /* CONFIG_NFS_V4_1 */
1718
1719 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1720  * on EXCHANGE_ID for v4.1
1721  */
1722 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1723 {
1724         switch (status) {
1725         case -NFS4ERR_CLID_INUSE:
1726         case -NFS4ERR_STALE_CLIENTID:
1727                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1728                 break;
1729         case -NFS4ERR_DELAY:
1730         case -ETIMEDOUT:
1731         case -EAGAIN:
1732                 ssleep(1);
1733                 break;
1734
1735         case -EKEYEXPIRED:
1736                 nfs4_warn_keyexpired(clp->cl_hostname);
1737         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1738                                  * in nfs4_exchange_id */
1739         default:
1740                 return;
1741         }
1742         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1743 }
1744
1745 static void nfs4_state_manager(struct nfs_client *clp)
1746 {
1747         int status = 0;
1748
1749         /* Ensure exclusive access to NFSv4 state */
1750         do {
1751                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1752                         /* We're going to have to re-establish a clientid */
1753                         status = nfs4_reclaim_lease(clp);
1754                         if (status) {
1755                                 nfs4_set_lease_expired(clp, status);
1756                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1757                                                         &clp->cl_state))
1758                                         continue;
1759                                 if (clp->cl_cons_state ==
1760                                                         NFS_CS_SESSION_INITING)
1761                                         nfs_mark_client_ready(clp, status);
1762                                 goto out_error;
1763                         }
1764                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1765
1766                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1767                                                &clp->cl_state))
1768                                 nfs4_state_start_reclaim_nograce(clp);
1769                         else
1770                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1771                                         &clp->cl_state);
1772
1773                         pnfs_destroy_all_layouts(clp);
1774                 }
1775
1776                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1777                         status = nfs4_check_lease(clp);
1778                         if (status < 0)
1779                                 goto out_error;
1780                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1781                                 continue;
1782                 }
1783
1784                 /* Initialize or reset the session */
1785                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1786                    && nfs4_has_session(clp)) {
1787                         status = nfs4_reset_session(clp);
1788                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1789                                 continue;
1790                         if (status < 0)
1791                                 goto out_error;
1792                 }
1793
1794                 /* First recover reboot state... */
1795                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1796                         status = nfs4_do_reclaim(clp,
1797                                 clp->cl_mvops->reboot_recovery_ops);
1798                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1799                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1800                                 continue;
1801                         nfs4_state_end_reclaim_reboot(clp);
1802                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1803                                 continue;
1804                         if (status < 0)
1805                                 goto out_error;
1806                 }
1807
1808                 /* Now recover expired state... */
1809                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1810                         status = nfs4_do_reclaim(clp,
1811                                 clp->cl_mvops->nograce_recovery_ops);
1812                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1813                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1814                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1815                                 continue;
1816                         if (status < 0)
1817                                 goto out_error;
1818                 }
1819
1820                 nfs4_end_drain_session(clp);
1821                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1822                         nfs_client_return_marked_delegations(clp);
1823                         continue;
1824                 }
1825                 /* Recall session slots */
1826                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1827                    && nfs4_has_session(clp)) {
1828                         status = nfs4_recall_slot(clp);
1829                         if (status < 0)
1830                                 goto out_error;
1831                         continue;
1832                 }
1833
1834
1835                 nfs4_clear_state_manager_bit(clp);
1836                 /* Did we race with an attempt to give us more work? */
1837                 if (clp->cl_state == 0)
1838                         break;
1839                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1840                         break;
1841         } while (atomic_read(&clp->cl_count) > 1);
1842         return;
1843 out_error:
1844         pr_warn_ratelimited("NFS: state manager failed on NFSv4 server %s"
1845                         " with error %d\n", clp->cl_hostname, -status);
1846         nfs4_end_drain_session(clp);
1847         nfs4_clear_state_manager_bit(clp);
1848 }
1849
1850 static int nfs4_run_state_manager(void *ptr)
1851 {
1852         struct nfs_client *clp = ptr;
1853
1854         allow_signal(SIGKILL);
1855         nfs4_state_manager(clp);
1856         nfs_put_client(clp);
1857         module_put_and_exit(0);
1858         return 0;
1859 }
1860
1861 /*
1862  * Local variables:
1863  *  c-basic-offset: 8
1864  * End:
1865  */