NFSv4: Ensure we do not reuse open owner names
[linux-2.6.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         /* Use machine credentials if available */
150         cred = nfs4_get_machine_cred_locked(clp);
151         if (cred != NULL)
152                 goto out;
153
154         rcu_read_lock();
155         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
156                 cred = nfs4_get_renew_cred_server_locked(server);
157                 if (cred != NULL)
158                         break;
159         }
160         rcu_read_unlock();
161
162 out:
163         return cred;
164 }
165
166 #if defined(CONFIG_NFS_V4_1)
167
168 static int nfs41_setup_state_renewal(struct nfs_client *clp)
169 {
170         int status;
171         struct nfs_fsinfo fsinfo;
172
173         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
174                 nfs4_schedule_state_renewal(clp);
175                 return 0;
176         }
177
178         status = nfs4_proc_get_lease_time(clp, &fsinfo);
179         if (status == 0) {
180                 /* Update lease time and schedule renewal */
181                 spin_lock(&clp->cl_lock);
182                 clp->cl_lease_time = fsinfo.lease_time * HZ;
183                 clp->cl_last_renewal = jiffies;
184                 spin_unlock(&clp->cl_lock);
185
186                 nfs4_schedule_state_renewal(clp);
187         }
188
189         return status;
190 }
191
192 /*
193  * Back channel returns NFS4ERR_DELAY for new requests when
194  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
195  * is ended.
196  */
197 static void nfs4_end_drain_session(struct nfs_client *clp)
198 {
199         struct nfs4_session *ses = clp->cl_session;
200         struct nfs4_slot_table *tbl;
201         int max_slots;
202
203         if (ses == NULL)
204                 return;
205         tbl = &ses->fc_slot_table;
206         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
207                 spin_lock(&tbl->slot_tbl_lock);
208                 max_slots = tbl->max_slots;
209                 while (max_slots--) {
210                         if (rpc_wake_up_first(&tbl->slot_tbl_waitq,
211                                                 nfs4_set_task_privileged,
212                                                 NULL) == NULL)
213                                 break;
214                 }
215                 spin_unlock(&tbl->slot_tbl_lock);
216         }
217 }
218
219 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
220 {
221         spin_lock(&tbl->slot_tbl_lock);
222         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
223                 INIT_COMPLETION(tbl->complete);
224                 spin_unlock(&tbl->slot_tbl_lock);
225                 return wait_for_completion_interruptible(&tbl->complete);
226         }
227         spin_unlock(&tbl->slot_tbl_lock);
228         return 0;
229 }
230
231 static int nfs4_begin_drain_session(struct nfs_client *clp)
232 {
233         struct nfs4_session *ses = clp->cl_session;
234         int ret = 0;
235
236         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
237         /* back channel */
238         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
239         if (ret)
240                 return ret;
241         /* fore channel */
242         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
243 }
244
245 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
246 {
247         int status;
248
249         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
250                 goto do_confirm;
251         nfs4_begin_drain_session(clp);
252         status = nfs4_proc_exchange_id(clp, cred);
253         if (status != 0)
254                 goto out;
255         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
256 do_confirm:
257         status = nfs4_proc_create_session(clp);
258         if (status != 0)
259                 goto out;
260         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
261         nfs41_setup_state_renewal(clp);
262         nfs_mark_client_ready(clp, NFS_CS_READY);
263 out:
264         return status;
265 }
266
267 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
268 {
269         struct rpc_cred *cred;
270
271         spin_lock(&clp->cl_lock);
272         cred = nfs4_get_machine_cred_locked(clp);
273         spin_unlock(&clp->cl_lock);
274         return cred;
275 }
276
277 #endif /* CONFIG_NFS_V4_1 */
278
279 static struct rpc_cred *
280 nfs4_get_setclientid_cred_server(struct nfs_server *server)
281 {
282         struct nfs_client *clp = server->nfs_client;
283         struct rpc_cred *cred = NULL;
284         struct nfs4_state_owner *sp;
285         struct rb_node *pos;
286
287         spin_lock(&clp->cl_lock);
288         pos = rb_first(&server->state_owners);
289         if (pos != NULL) {
290                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
291                 cred = get_rpccred(sp->so_cred);
292         }
293         spin_unlock(&clp->cl_lock);
294         return cred;
295 }
296
297 /**
298  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
299  * @clp: client state handle
300  *
301  * Returns an rpc_cred with reference count bumped, or NULL.
302  */
303 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
304 {
305         struct nfs_server *server;
306         struct rpc_cred *cred;
307
308         spin_lock(&clp->cl_lock);
309         cred = nfs4_get_machine_cred_locked(clp);
310         spin_unlock(&clp->cl_lock);
311         if (cred != NULL)
312                 goto out;
313
314         rcu_read_lock();
315         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
316                 cred = nfs4_get_setclientid_cred_server(server);
317                 if (cred != NULL)
318                         break;
319         }
320         rcu_read_unlock();
321
322 out:
323         return cred;
324 }
325
326 static struct nfs4_state_owner *
327 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
328 {
329         struct rb_node **p = &server->state_owners.rb_node,
330                        *parent = NULL;
331         struct nfs4_state_owner *sp;
332
333         while (*p != NULL) {
334                 parent = *p;
335                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
336
337                 if (cred < sp->so_cred)
338                         p = &parent->rb_left;
339                 else if (cred > sp->so_cred)
340                         p = &parent->rb_right;
341                 else {
342                         if (!list_empty(&sp->so_lru))
343                                 list_del_init(&sp->so_lru);
344                         atomic_inc(&sp->so_count);
345                         return sp;
346                 }
347         }
348         return NULL;
349 }
350
351 static struct nfs4_state_owner *
352 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
353 {
354         struct nfs_server *server = new->so_server;
355         struct rb_node **p = &server->state_owners.rb_node,
356                        *parent = NULL;
357         struct nfs4_state_owner *sp;
358         int err;
359
360         while (*p != NULL) {
361                 parent = *p;
362                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
363
364                 if (new->so_cred < sp->so_cred)
365                         p = &parent->rb_left;
366                 else if (new->so_cred > sp->so_cred)
367                         p = &parent->rb_right;
368                 else {
369                         if (!list_empty(&sp->so_lru))
370                                 list_del_init(&sp->so_lru);
371                         atomic_inc(&sp->so_count);
372                         return sp;
373                 }
374         }
375         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
376         if (err)
377                 return ERR_PTR(err);
378         rb_link_node(&new->so_server_node, parent, p);
379         rb_insert_color(&new->so_server_node, &server->state_owners);
380         return new;
381 }
382
383 static void
384 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
385 {
386         struct nfs_server *server = sp->so_server;
387
388         if (!RB_EMPTY_NODE(&sp->so_server_node))
389                 rb_erase(&sp->so_server_node, &server->state_owners);
390         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
391 }
392
393 static void
394 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
395 {
396         sc->create_time = ktime_get();
397         sc->flags = 0;
398         sc->counter = 0;
399         spin_lock_init(&sc->lock);
400         INIT_LIST_HEAD(&sc->list);
401         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
402 }
403
404 static void
405 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
406 {
407         rpc_destroy_wait_queue(&sc->wait);
408 }
409
410 /*
411  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
412  * create a new state_owner.
413  *
414  */
415 static struct nfs4_state_owner *
416 nfs4_alloc_state_owner(struct nfs_server *server,
417                 struct rpc_cred *cred,
418                 gfp_t gfp_flags)
419 {
420         struct nfs4_state_owner *sp;
421
422         sp = kzalloc(sizeof(*sp), gfp_flags);
423         if (!sp)
424                 return NULL;
425         sp->so_server = server;
426         sp->so_cred = get_rpccred(cred);
427         spin_lock_init(&sp->so_lock);
428         INIT_LIST_HEAD(&sp->so_states);
429         nfs4_init_seqid_counter(&sp->so_seqid);
430         atomic_set(&sp->so_count, 1);
431         INIT_LIST_HEAD(&sp->so_lru);
432         return sp;
433 }
434
435 static void
436 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
437 {
438         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
439                 struct nfs_server *server = sp->so_server;
440                 struct nfs_client *clp = server->nfs_client;
441
442                 spin_lock(&clp->cl_lock);
443                 rb_erase(&sp->so_server_node, &server->state_owners);
444                 RB_CLEAR_NODE(&sp->so_server_node);
445                 spin_unlock(&clp->cl_lock);
446         }
447 }
448
449 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
450 {
451         nfs4_destroy_seqid_counter(&sp->so_seqid);
452         put_rpccred(sp->so_cred);
453         kfree(sp);
454 }
455
456 static void nfs4_gc_state_owners(struct nfs_server *server)
457 {
458         struct nfs_client *clp = server->nfs_client;
459         struct nfs4_state_owner *sp, *tmp;
460         unsigned long time_min, time_max;
461         LIST_HEAD(doomed);
462
463         spin_lock(&clp->cl_lock);
464         time_max = jiffies;
465         time_min = (long)time_max - (long)clp->cl_lease_time;
466         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
467                 /* NB: LRU is sorted so that oldest is at the head */
468                 if (time_in_range(sp->so_expires, time_min, time_max))
469                         break;
470                 list_move(&sp->so_lru, &doomed);
471                 nfs4_remove_state_owner_locked(sp);
472         }
473         spin_unlock(&clp->cl_lock);
474
475         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
476                 list_del(&sp->so_lru);
477                 nfs4_free_state_owner(sp);
478         }
479 }
480
481 /**
482  * nfs4_get_state_owner - Look up a state owner given a credential
483  * @server: nfs_server to search
484  * @cred: RPC credential to match
485  *
486  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
487  */
488 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
489                                               struct rpc_cred *cred,
490                                               gfp_t gfp_flags)
491 {
492         struct nfs_client *clp = server->nfs_client;
493         struct nfs4_state_owner *sp, *new;
494
495         spin_lock(&clp->cl_lock);
496         sp = nfs4_find_state_owner_locked(server, cred);
497         spin_unlock(&clp->cl_lock);
498         if (sp != NULL)
499                 goto out;
500         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
501         if (new == NULL)
502                 goto out;
503         do {
504                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
505                         break;
506                 spin_lock(&clp->cl_lock);
507                 sp = nfs4_insert_state_owner_locked(new);
508                 spin_unlock(&clp->cl_lock);
509         } while (sp == ERR_PTR(-EAGAIN));
510         if (sp != new)
511                 nfs4_free_state_owner(new);
512 out:
513         nfs4_gc_state_owners(server);
514         return sp;
515 }
516
517 /**
518  * nfs4_put_state_owner - Release a nfs4_state_owner
519  * @sp: state owner data to release
520  */
521 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
522 {
523         struct nfs_server *server = sp->so_server;
524         struct nfs_client *clp = server->nfs_client;
525
526         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
527                 return;
528
529         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
530                 sp->so_expires = jiffies;
531                 list_add_tail(&sp->so_lru, &server->state_owners_lru);
532                 spin_unlock(&clp->cl_lock);
533         } else {
534                 nfs4_remove_state_owner_locked(sp);
535                 spin_unlock(&clp->cl_lock);
536                 nfs4_free_state_owner(sp);
537         }
538 }
539
540 /**
541  * nfs4_purge_state_owners - Release all cached state owners
542  * @server: nfs_server with cached state owners to release
543  *
544  * Called at umount time.  Remaining state owners will be on
545  * the LRU with ref count of zero.
546  */
547 void nfs4_purge_state_owners(struct nfs_server *server)
548 {
549         struct nfs_client *clp = server->nfs_client;
550         struct nfs4_state_owner *sp, *tmp;
551         LIST_HEAD(doomed);
552
553         spin_lock(&clp->cl_lock);
554         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
555                 list_move(&sp->so_lru, &doomed);
556                 nfs4_remove_state_owner_locked(sp);
557         }
558         spin_unlock(&clp->cl_lock);
559
560         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
561                 list_del(&sp->so_lru);
562                 nfs4_free_state_owner(sp);
563         }
564 }
565
566 static struct nfs4_state *
567 nfs4_alloc_open_state(void)
568 {
569         struct nfs4_state *state;
570
571         state = kzalloc(sizeof(*state), GFP_NOFS);
572         if (!state)
573                 return NULL;
574         atomic_set(&state->count, 1);
575         INIT_LIST_HEAD(&state->lock_states);
576         spin_lock_init(&state->state_lock);
577         seqlock_init(&state->seqlock);
578         return state;
579 }
580
581 void
582 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
583 {
584         if (state->state == fmode)
585                 return;
586         /* NB! List reordering - see the reclaim code for why.  */
587         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
588                 if (fmode & FMODE_WRITE)
589                         list_move(&state->open_states, &state->owner->so_states);
590                 else
591                         list_move_tail(&state->open_states, &state->owner->so_states);
592         }
593         state->state = fmode;
594 }
595
596 static struct nfs4_state *
597 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
598 {
599         struct nfs_inode *nfsi = NFS_I(inode);
600         struct nfs4_state *state;
601
602         list_for_each_entry(state, &nfsi->open_states, inode_states) {
603                 if (state->owner != owner)
604                         continue;
605                 if (atomic_inc_not_zero(&state->count))
606                         return state;
607         }
608         return NULL;
609 }
610
611 static void
612 nfs4_free_open_state(struct nfs4_state *state)
613 {
614         kfree(state);
615 }
616
617 struct nfs4_state *
618 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
619 {
620         struct nfs4_state *state, *new;
621         struct nfs_inode *nfsi = NFS_I(inode);
622
623         spin_lock(&inode->i_lock);
624         state = __nfs4_find_state_byowner(inode, owner);
625         spin_unlock(&inode->i_lock);
626         if (state)
627                 goto out;
628         new = nfs4_alloc_open_state();
629         spin_lock(&owner->so_lock);
630         spin_lock(&inode->i_lock);
631         state = __nfs4_find_state_byowner(inode, owner);
632         if (state == NULL && new != NULL) {
633                 state = new;
634                 state->owner = owner;
635                 atomic_inc(&owner->so_count);
636                 list_add(&state->inode_states, &nfsi->open_states);
637                 ihold(inode);
638                 state->inode = inode;
639                 spin_unlock(&inode->i_lock);
640                 /* Note: The reclaim code dictates that we add stateless
641                  * and read-only stateids to the end of the list */
642                 list_add_tail(&state->open_states, &owner->so_states);
643                 spin_unlock(&owner->so_lock);
644         } else {
645                 spin_unlock(&inode->i_lock);
646                 spin_unlock(&owner->so_lock);
647                 if (new)
648                         nfs4_free_open_state(new);
649         }
650 out:
651         return state;
652 }
653
654 void nfs4_put_open_state(struct nfs4_state *state)
655 {
656         struct inode *inode = state->inode;
657         struct nfs4_state_owner *owner = state->owner;
658
659         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
660                 return;
661         spin_lock(&inode->i_lock);
662         list_del(&state->inode_states);
663         list_del(&state->open_states);
664         spin_unlock(&inode->i_lock);
665         spin_unlock(&owner->so_lock);
666         iput(inode);
667         nfs4_free_open_state(state);
668         nfs4_put_state_owner(owner);
669 }
670
671 /*
672  * Close the current file.
673  */
674 static void __nfs4_close(struct nfs4_state *state,
675                 fmode_t fmode, gfp_t gfp_mask, int wait)
676 {
677         struct nfs4_state_owner *owner = state->owner;
678         int call_close = 0;
679         fmode_t newstate;
680
681         atomic_inc(&owner->so_count);
682         /* Protect against nfs4_find_state() */
683         spin_lock(&owner->so_lock);
684         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
685                 case FMODE_READ:
686                         state->n_rdonly--;
687                         break;
688                 case FMODE_WRITE:
689                         state->n_wronly--;
690                         break;
691                 case FMODE_READ|FMODE_WRITE:
692                         state->n_rdwr--;
693         }
694         newstate = FMODE_READ|FMODE_WRITE;
695         if (state->n_rdwr == 0) {
696                 if (state->n_rdonly == 0) {
697                         newstate &= ~FMODE_READ;
698                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
699                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
700                 }
701                 if (state->n_wronly == 0) {
702                         newstate &= ~FMODE_WRITE;
703                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
704                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
705                 }
706                 if (newstate == 0)
707                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
708         }
709         nfs4_state_set_mode_locked(state, newstate);
710         spin_unlock(&owner->so_lock);
711
712         if (!call_close) {
713                 nfs4_put_open_state(state);
714                 nfs4_put_state_owner(owner);
715         } else {
716                 bool roc = pnfs_roc(state->inode);
717
718                 nfs4_do_close(state, gfp_mask, wait, roc);
719         }
720 }
721
722 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
723 {
724         __nfs4_close(state, fmode, GFP_NOFS, 0);
725 }
726
727 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
728 {
729         __nfs4_close(state, fmode, GFP_KERNEL, 1);
730 }
731
732 /*
733  * Search the state->lock_states for an existing lock_owner
734  * that is compatible with current->files
735  */
736 static struct nfs4_lock_state *
737 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
738 {
739         struct nfs4_lock_state *pos;
740         list_for_each_entry(pos, &state->lock_states, ls_locks) {
741                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
742                         continue;
743                 switch (pos->ls_owner.lo_type) {
744                 case NFS4_POSIX_LOCK_TYPE:
745                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
746                                 continue;
747                         break;
748                 case NFS4_FLOCK_LOCK_TYPE:
749                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
750                                 continue;
751                 }
752                 atomic_inc(&pos->ls_count);
753                 return pos;
754         }
755         return NULL;
756 }
757
758 /*
759  * Return a compatible lock_state. If no initialized lock_state structure
760  * exists, return an uninitialized one.
761  *
762  */
763 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)
764 {
765         struct nfs4_lock_state *lsp;
766         struct nfs_server *server = state->owner->so_server;
767
768         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
769         if (lsp == NULL)
770                 return NULL;
771         nfs4_init_seqid_counter(&lsp->ls_seqid);
772         atomic_set(&lsp->ls_count, 1);
773         lsp->ls_state = state;
774         lsp->ls_owner.lo_type = type;
775         switch (lsp->ls_owner.lo_type) {
776         case NFS4_FLOCK_LOCK_TYPE:
777                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
778                 break;
779         case NFS4_POSIX_LOCK_TYPE:
780                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
781                 break;
782         default:
783                 goto out_free;
784         }
785         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
786         if (lsp->ls_seqid.owner_id < 0)
787                 goto out_free;
788         INIT_LIST_HEAD(&lsp->ls_locks);
789         return lsp;
790 out_free:
791         kfree(lsp);
792         return NULL;
793 }
794
795 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
796 {
797         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
798         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
799         kfree(lsp);
800 }
801
802 /*
803  * Return a compatible lock_state. If no initialized lock_state structure
804  * exists, return an uninitialized one.
805  *
806  */
807 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
808 {
809         struct nfs4_lock_state *lsp, *new = NULL;
810         
811         for(;;) {
812                 spin_lock(&state->state_lock);
813                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
814                 if (lsp != NULL)
815                         break;
816                 if (new != NULL) {
817                         list_add(&new->ls_locks, &state->lock_states);
818                         set_bit(LK_STATE_IN_USE, &state->flags);
819                         lsp = new;
820                         new = NULL;
821                         break;
822                 }
823                 spin_unlock(&state->state_lock);
824                 new = nfs4_alloc_lock_state(state, owner, pid, type);
825                 if (new == NULL)
826                         return NULL;
827         }
828         spin_unlock(&state->state_lock);
829         if (new != NULL)
830                 nfs4_free_lock_state(state->owner->so_server, new);
831         return lsp;
832 }
833
834 /*
835  * Release reference to lock_state, and free it if we see that
836  * it is no longer in use
837  */
838 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
839 {
840         struct nfs4_state *state;
841
842         if (lsp == NULL)
843                 return;
844         state = lsp->ls_state;
845         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
846                 return;
847         list_del(&lsp->ls_locks);
848         if (list_empty(&state->lock_states))
849                 clear_bit(LK_STATE_IN_USE, &state->flags);
850         spin_unlock(&state->state_lock);
851         if (lsp->ls_flags & NFS_LOCK_INITIALIZED) {
852                 if (nfs4_release_lockowner(lsp) == 0)
853                         return;
854         }
855         nfs4_free_lock_state(lsp->ls_state->owner->so_server, lsp);
856 }
857
858 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
859 {
860         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
861
862         dst->fl_u.nfs4_fl.owner = lsp;
863         atomic_inc(&lsp->ls_count);
864 }
865
866 static void nfs4_fl_release_lock(struct file_lock *fl)
867 {
868         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
869 }
870
871 static const struct file_lock_operations nfs4_fl_lock_ops = {
872         .fl_copy_lock = nfs4_fl_copy_lock,
873         .fl_release_private = nfs4_fl_release_lock,
874 };
875
876 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
877 {
878         struct nfs4_lock_state *lsp;
879
880         if (fl->fl_ops != NULL)
881                 return 0;
882         if (fl->fl_flags & FL_POSIX)
883                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
884         else if (fl->fl_flags & FL_FLOCK)
885                 lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
886                                 NFS4_FLOCK_LOCK_TYPE);
887         else
888                 return -EINVAL;
889         if (lsp == NULL)
890                 return -ENOMEM;
891         fl->fl_u.nfs4_fl.owner = lsp;
892         fl->fl_ops = &nfs4_fl_lock_ops;
893         return 0;
894 }
895
896 static bool nfs4_copy_lock_stateid(nfs4_stateid *dst, struct nfs4_state *state,
897                 fl_owner_t fl_owner, pid_t fl_pid)
898 {
899         struct nfs4_lock_state *lsp;
900         bool ret = false;
901
902         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
903                 goto out;
904
905         spin_lock(&state->state_lock);
906         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
907         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0) {
908                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
909                 ret = true;
910         }
911         spin_unlock(&state->state_lock);
912         nfs4_put_lock_state(lsp);
913 out:
914         return ret;
915 }
916
917 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
918 {
919         int seq;
920
921         do {
922                 seq = read_seqbegin(&state->seqlock);
923                 nfs4_stateid_copy(dst, &state->stateid);
924         } while (read_seqretry(&state->seqlock, seq));
925 }
926
927 /*
928  * Byte-range lock aware utility to initialize the stateid of read/write
929  * requests.
930  */
931 void nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
932                 fmode_t fmode, fl_owner_t fl_owner, pid_t fl_pid)
933 {
934         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
935                 return;
936         if (nfs4_copy_lock_stateid(dst, state, fl_owner, fl_pid))
937                 return;
938         nfs4_copy_open_stateid(dst, state);
939 }
940
941 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
942 {
943         struct nfs_seqid *new;
944
945         new = kmalloc(sizeof(*new), gfp_mask);
946         if (new != NULL) {
947                 new->sequence = counter;
948                 INIT_LIST_HEAD(&new->list);
949                 new->task = NULL;
950         }
951         return new;
952 }
953
954 void nfs_release_seqid(struct nfs_seqid *seqid)
955 {
956         struct nfs_seqid_counter *sequence;
957
958         if (list_empty(&seqid->list))
959                 return;
960         sequence = seqid->sequence;
961         spin_lock(&sequence->lock);
962         list_del_init(&seqid->list);
963         if (!list_empty(&sequence->list)) {
964                 struct nfs_seqid *next;
965
966                 next = list_first_entry(&sequence->list,
967                                 struct nfs_seqid, list);
968                 rpc_wake_up_queued_task(&sequence->wait, next->task);
969         }
970         spin_unlock(&sequence->lock);
971 }
972
973 void nfs_free_seqid(struct nfs_seqid *seqid)
974 {
975         nfs_release_seqid(seqid);
976         kfree(seqid);
977 }
978
979 /*
980  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
981  * failed with a seqid incrementing error -
982  * see comments nfs_fs.h:seqid_mutating_error()
983  */
984 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
985 {
986         BUG_ON(list_first_entry(&seqid->sequence->list, struct nfs_seqid, list) != seqid);
987         switch (status) {
988                 case 0:
989                         break;
990                 case -NFS4ERR_BAD_SEQID:
991                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
992                                 return;
993                         pr_warn_ratelimited("NFS: v4 server returned a bad"
994                                         " sequence-id error on an"
995                                         " unconfirmed sequence %p!\n",
996                                         seqid->sequence);
997                 case -NFS4ERR_STALE_CLIENTID:
998                 case -NFS4ERR_STALE_STATEID:
999                 case -NFS4ERR_BAD_STATEID:
1000                 case -NFS4ERR_BADXDR:
1001                 case -NFS4ERR_RESOURCE:
1002                 case -NFS4ERR_NOFILEHANDLE:
1003                         /* Non-seqid mutating errors */
1004                         return;
1005         };
1006         /*
1007          * Note: no locking needed as we are guaranteed to be first
1008          * on the sequence list
1009          */
1010         seqid->sequence->counter++;
1011 }
1012
1013 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1014 {
1015         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1016                                         struct nfs4_state_owner, so_seqid);
1017         struct nfs_server *server = sp->so_server;
1018
1019         if (status == -NFS4ERR_BAD_SEQID)
1020                 nfs4_drop_state_owner(sp);
1021         if (!nfs4_has_session(server->nfs_client))
1022                 nfs_increment_seqid(status, seqid);
1023 }
1024
1025 /*
1026  * Increment the seqid if the LOCK/LOCKU succeeded, or
1027  * failed with a seqid incrementing error -
1028  * see comments nfs_fs.h:seqid_mutating_error()
1029  */
1030 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1031 {
1032         nfs_increment_seqid(status, seqid);
1033 }
1034
1035 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1036 {
1037         struct nfs_seqid_counter *sequence = seqid->sequence;
1038         int status = 0;
1039
1040         spin_lock(&sequence->lock);
1041         seqid->task = task;
1042         if (list_empty(&seqid->list))
1043                 list_add_tail(&seqid->list, &sequence->list);
1044         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1045                 goto unlock;
1046         rpc_sleep_on(&sequence->wait, task, NULL);
1047         status = -EAGAIN;
1048 unlock:
1049         spin_unlock(&sequence->lock);
1050         return status;
1051 }
1052
1053 static int nfs4_run_state_manager(void *);
1054
1055 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1056 {
1057         smp_mb__before_clear_bit();
1058         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1059         smp_mb__after_clear_bit();
1060         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1061         rpc_wake_up(&clp->cl_rpcwaitq);
1062 }
1063
1064 /*
1065  * Schedule the nfs_client asynchronous state management routine
1066  */
1067 void nfs4_schedule_state_manager(struct nfs_client *clp)
1068 {
1069         struct task_struct *task;
1070         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1071
1072         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1073                 return;
1074         __module_get(THIS_MODULE);
1075         atomic_inc(&clp->cl_count);
1076
1077         /* The rcu_read_lock() is not strictly necessary, as the state
1078          * manager is the only thread that ever changes the rpc_xprt
1079          * after it's initialized.  At this point, we're single threaded. */
1080         rcu_read_lock();
1081         snprintf(buf, sizeof(buf), "%s-manager",
1082                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1083         rcu_read_unlock();
1084         task = kthread_run(nfs4_run_state_manager, clp, buf);
1085         if (IS_ERR(task)) {
1086                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1087                         __func__, PTR_ERR(task));
1088                 nfs4_clear_state_manager_bit(clp);
1089                 nfs_put_client(clp);
1090                 module_put(THIS_MODULE);
1091         }
1092 }
1093
1094 /*
1095  * Schedule a lease recovery attempt
1096  */
1097 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1098 {
1099         if (!clp)
1100                 return;
1101         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1102                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1103         nfs4_schedule_state_manager(clp);
1104 }
1105 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1106
1107 /*
1108  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1109  * @clp: client to process
1110  *
1111  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1112  * resend of the SETCLIENTID and hence re-establish the
1113  * callback channel. Then return all existing delegations.
1114  */
1115 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1116 {
1117         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1118         nfs_expire_all_delegations(clp);
1119 }
1120
1121 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1122 {
1123         nfs40_handle_cb_pathdown(clp);
1124         nfs4_schedule_state_manager(clp);
1125 }
1126
1127 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1128 {
1129
1130         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1131         /* Don't recover state that expired before the reboot */
1132         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1133                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1134                 return 0;
1135         }
1136         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1137         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1138         return 1;
1139 }
1140
1141 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1142 {
1143         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1144         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1145         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1146         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1147         return 1;
1148 }
1149
1150 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1151 {
1152         struct nfs_client *clp = server->nfs_client;
1153
1154         nfs4_state_mark_reclaim_nograce(clp, state);
1155         nfs4_schedule_state_manager(clp);
1156 }
1157 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1158
1159 void nfs_inode_find_state_and_recover(struct inode *inode,
1160                 const nfs4_stateid *stateid)
1161 {
1162         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1163         struct nfs_inode *nfsi = NFS_I(inode);
1164         struct nfs_open_context *ctx;
1165         struct nfs4_state *state;
1166         bool found = false;
1167
1168         spin_lock(&inode->i_lock);
1169         list_for_each_entry(ctx, &nfsi->open_files, list) {
1170                 state = ctx->state;
1171                 if (state == NULL)
1172                         continue;
1173                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1174                         continue;
1175                 if (!nfs4_stateid_match(&state->stateid, stateid))
1176                         continue;
1177                 nfs4_state_mark_reclaim_nograce(clp, state);
1178                 found = true;
1179         }
1180         spin_unlock(&inode->i_lock);
1181         if (found)
1182                 nfs4_schedule_state_manager(clp);
1183 }
1184
1185
1186 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1187 {
1188         struct inode *inode = state->inode;
1189         struct nfs_inode *nfsi = NFS_I(inode);
1190         struct file_lock *fl;
1191         int status = 0;
1192
1193         if (inode->i_flock == NULL)
1194                 return 0;
1195
1196         /* Guard against delegation returns and new lock/unlock calls */
1197         down_write(&nfsi->rwsem);
1198         /* Protect inode->i_flock using the BKL */
1199         lock_flocks();
1200         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1201                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1202                         continue;
1203                 if (nfs_file_open_context(fl->fl_file)->state != state)
1204                         continue;
1205                 unlock_flocks();
1206                 status = ops->recover_lock(state, fl);
1207                 switch (status) {
1208                         case 0:
1209                                 break;
1210                         case -ESTALE:
1211                         case -NFS4ERR_ADMIN_REVOKED:
1212                         case -NFS4ERR_STALE_STATEID:
1213                         case -NFS4ERR_BAD_STATEID:
1214                         case -NFS4ERR_EXPIRED:
1215                         case -NFS4ERR_NO_GRACE:
1216                         case -NFS4ERR_STALE_CLIENTID:
1217                         case -NFS4ERR_BADSESSION:
1218                         case -NFS4ERR_BADSLOT:
1219                         case -NFS4ERR_BAD_HIGH_SLOT:
1220                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1221                                 goto out;
1222                         default:
1223                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1224                                         "Zeroing state\n", __func__, status);
1225                         case -ENOMEM:
1226                         case -NFS4ERR_DENIED:
1227                         case -NFS4ERR_RECLAIM_BAD:
1228                         case -NFS4ERR_RECLAIM_CONFLICT:
1229                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1230                                 status = 0;
1231                 }
1232                 lock_flocks();
1233         }
1234         unlock_flocks();
1235 out:
1236         up_write(&nfsi->rwsem);
1237         return status;
1238 }
1239
1240 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1241 {
1242         struct nfs4_state *state;
1243         struct nfs4_lock_state *lock;
1244         int status = 0;
1245
1246         /* Note: we rely on the sp->so_states list being ordered 
1247          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1248          * states first.
1249          * This is needed to ensure that the server won't give us any
1250          * read delegations that we have to return if, say, we are
1251          * recovering after a network partition or a reboot from a
1252          * server that doesn't support a grace period.
1253          */
1254 restart:
1255         spin_lock(&sp->so_lock);
1256         list_for_each_entry(state, &sp->so_states, open_states) {
1257                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1258                         continue;
1259                 if (state->state == 0)
1260                         continue;
1261                 atomic_inc(&state->count);
1262                 spin_unlock(&sp->so_lock);
1263                 status = ops->recover_open(sp, state);
1264                 if (status >= 0) {
1265                         status = nfs4_reclaim_locks(state, ops);
1266                         if (status >= 0) {
1267                                 spin_lock(&state->state_lock);
1268                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1269                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1270                                                 pr_warn_ratelimited("NFS: "
1271                                                         "%s: Lock reclaim "
1272                                                         "failed!\n", __func__);
1273                                 }
1274                                 spin_unlock(&state->state_lock);
1275                                 nfs4_put_open_state(state);
1276                                 goto restart;
1277                         }
1278                 }
1279                 switch (status) {
1280                         default:
1281                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1282                                         "Zeroing state\n", __func__, status);
1283                         case -ENOENT:
1284                         case -ENOMEM:
1285                         case -ESTALE:
1286                                 /*
1287                                  * Open state on this file cannot be recovered
1288                                  * All we can do is revert to using the zero stateid.
1289                                  */
1290                                 memset(&state->stateid, 0,
1291                                         sizeof(state->stateid));
1292                                 /* Mark the file as being 'closed' */
1293                                 state->state = 0;
1294                                 break;
1295                         case -EKEYEXPIRED:
1296                                 /*
1297                                  * User RPCSEC_GSS context has expired.
1298                                  * We cannot recover this stateid now, so
1299                                  * skip it and allow recovery thread to
1300                                  * proceed.
1301                                  */
1302                                 break;
1303                         case -NFS4ERR_ADMIN_REVOKED:
1304                         case -NFS4ERR_STALE_STATEID:
1305                         case -NFS4ERR_BAD_STATEID:
1306                         case -NFS4ERR_RECLAIM_BAD:
1307                         case -NFS4ERR_RECLAIM_CONFLICT:
1308                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1309                                 break;
1310                         case -NFS4ERR_EXPIRED:
1311                         case -NFS4ERR_NO_GRACE:
1312                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1313                         case -NFS4ERR_STALE_CLIENTID:
1314                         case -NFS4ERR_BADSESSION:
1315                         case -NFS4ERR_BADSLOT:
1316                         case -NFS4ERR_BAD_HIGH_SLOT:
1317                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1318                                 goto out_err;
1319                 }
1320                 nfs4_put_open_state(state);
1321                 goto restart;
1322         }
1323         spin_unlock(&sp->so_lock);
1324         return 0;
1325 out_err:
1326         nfs4_put_open_state(state);
1327         return status;
1328 }
1329
1330 static void nfs4_clear_open_state(struct nfs4_state *state)
1331 {
1332         struct nfs4_lock_state *lock;
1333
1334         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1335         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1336         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1337         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1338         spin_lock(&state->state_lock);
1339         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1340                 lock->ls_seqid.flags = 0;
1341                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1342         }
1343         spin_unlock(&state->state_lock);
1344 }
1345
1346 static void nfs4_reset_seqids(struct nfs_server *server,
1347         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1348 {
1349         struct nfs_client *clp = server->nfs_client;
1350         struct nfs4_state_owner *sp;
1351         struct rb_node *pos;
1352         struct nfs4_state *state;
1353
1354         spin_lock(&clp->cl_lock);
1355         for (pos = rb_first(&server->state_owners);
1356              pos != NULL;
1357              pos = rb_next(pos)) {
1358                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1359                 sp->so_seqid.flags = 0;
1360                 spin_lock(&sp->so_lock);
1361                 list_for_each_entry(state, &sp->so_states, open_states) {
1362                         if (mark_reclaim(clp, state))
1363                                 nfs4_clear_open_state(state);
1364                 }
1365                 spin_unlock(&sp->so_lock);
1366         }
1367         spin_unlock(&clp->cl_lock);
1368 }
1369
1370 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1371         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1372 {
1373         struct nfs_server *server;
1374
1375         rcu_read_lock();
1376         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1377                 nfs4_reset_seqids(server, mark_reclaim);
1378         rcu_read_unlock();
1379 }
1380
1381 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1382 {
1383         /* Mark all delegations for reclaim */
1384         nfs_delegation_mark_reclaim(clp);
1385         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1386 }
1387
1388 static void nfs4_reclaim_complete(struct nfs_client *clp,
1389                                  const struct nfs4_state_recovery_ops *ops)
1390 {
1391         /* Notify the server we're done reclaiming our state */
1392         if (ops->reclaim_complete)
1393                 (void)ops->reclaim_complete(clp);
1394 }
1395
1396 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1397 {
1398         struct nfs_client *clp = server->nfs_client;
1399         struct nfs4_state_owner *sp;
1400         struct rb_node *pos;
1401         struct nfs4_state *state;
1402
1403         spin_lock(&clp->cl_lock);
1404         for (pos = rb_first(&server->state_owners);
1405              pos != NULL;
1406              pos = rb_next(pos)) {
1407                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1408                 spin_lock(&sp->so_lock);
1409                 list_for_each_entry(state, &sp->so_states, open_states) {
1410                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1411                                                 &state->flags))
1412                                 continue;
1413                         nfs4_state_mark_reclaim_nograce(clp, state);
1414                 }
1415                 spin_unlock(&sp->so_lock);
1416         }
1417         spin_unlock(&clp->cl_lock);
1418 }
1419
1420 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1421 {
1422         struct nfs_server *server;
1423
1424         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1425                 return 0;
1426
1427         rcu_read_lock();
1428         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1429                 nfs4_clear_reclaim_server(server);
1430         rcu_read_unlock();
1431
1432         nfs_delegation_reap_unclaimed(clp);
1433         return 1;
1434 }
1435
1436 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1437 {
1438         if (!nfs4_state_clear_reclaim_reboot(clp))
1439                 return;
1440         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1441 }
1442
1443 static void nfs_delegation_clear_all(struct nfs_client *clp)
1444 {
1445         nfs_delegation_mark_reclaim(clp);
1446         nfs_delegation_reap_unclaimed(clp);
1447 }
1448
1449 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1450 {
1451         nfs_delegation_clear_all(clp);
1452         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1453 }
1454
1455 static void nfs4_warn_keyexpired(const char *s)
1456 {
1457         printk_ratelimited(KERN_WARNING "Error: state manager"
1458                         " encountered RPCSEC_GSS session"
1459                         " expired against NFSv4 server %s.\n",
1460                         s);
1461 }
1462
1463 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1464 {
1465         switch (error) {
1466                 case 0:
1467                         break;
1468                 case -NFS4ERR_CB_PATH_DOWN:
1469                         nfs40_handle_cb_pathdown(clp);
1470                         break;
1471                 case -NFS4ERR_NO_GRACE:
1472                         nfs4_state_end_reclaim_reboot(clp);
1473                         break;
1474                 case -NFS4ERR_STALE_CLIENTID:
1475                 case -NFS4ERR_LEASE_MOVED:
1476                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1477                         nfs4_state_clear_reclaim_reboot(clp);
1478                         nfs4_state_start_reclaim_reboot(clp);
1479                         break;
1480                 case -NFS4ERR_EXPIRED:
1481                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1482                         nfs4_state_start_reclaim_nograce(clp);
1483                         break;
1484                 case -NFS4ERR_BADSESSION:
1485                 case -NFS4ERR_BADSLOT:
1486                 case -NFS4ERR_BAD_HIGH_SLOT:
1487                 case -NFS4ERR_DEADSESSION:
1488                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1489                 case -NFS4ERR_SEQ_FALSE_RETRY:
1490                 case -NFS4ERR_SEQ_MISORDERED:
1491                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1492                         /* Zero session reset errors */
1493                         break;
1494                 case -EKEYEXPIRED:
1495                         /* Nothing we can do */
1496                         nfs4_warn_keyexpired(clp->cl_hostname);
1497                         break;
1498                 default:
1499                         return error;
1500         }
1501         return 0;
1502 }
1503
1504 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1505 {
1506         struct nfs4_state_owner *sp;
1507         struct nfs_server *server;
1508         struct rb_node *pos;
1509         int status = 0;
1510
1511 restart:
1512         rcu_read_lock();
1513         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1514                 nfs4_purge_state_owners(server);
1515                 spin_lock(&clp->cl_lock);
1516                 for (pos = rb_first(&server->state_owners);
1517                      pos != NULL;
1518                      pos = rb_next(pos)) {
1519                         sp = rb_entry(pos,
1520                                 struct nfs4_state_owner, so_server_node);
1521                         if (!test_and_clear_bit(ops->owner_flag_bit,
1522                                                         &sp->so_flags))
1523                                 continue;
1524                         atomic_inc(&sp->so_count);
1525                         spin_unlock(&clp->cl_lock);
1526                         rcu_read_unlock();
1527
1528                         status = nfs4_reclaim_open_state(sp, ops);
1529                         if (status < 0) {
1530                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1531                                 nfs4_put_state_owner(sp);
1532                                 return nfs4_recovery_handle_error(clp, status);
1533                         }
1534
1535                         nfs4_put_state_owner(sp);
1536                         goto restart;
1537                 }
1538                 spin_unlock(&clp->cl_lock);
1539         }
1540         rcu_read_unlock();
1541         return status;
1542 }
1543
1544 static int nfs4_check_lease(struct nfs_client *clp)
1545 {
1546         struct rpc_cred *cred;
1547         const struct nfs4_state_maintenance_ops *ops =
1548                 clp->cl_mvops->state_renewal_ops;
1549         int status;
1550
1551         /* Is the client already known to have an expired lease? */
1552         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1553                 return 0;
1554         spin_lock(&clp->cl_lock);
1555         cred = ops->get_state_renewal_cred_locked(clp);
1556         spin_unlock(&clp->cl_lock);
1557         if (cred == NULL) {
1558                 cred = nfs4_get_setclientid_cred(clp);
1559                 status = -ENOKEY;
1560                 if (cred == NULL)
1561                         goto out;
1562         }
1563         status = ops->renew_lease(clp, cred);
1564         put_rpccred(cred);
1565 out:
1566         return nfs4_recovery_handle_error(clp, status);
1567 }
1568
1569 static int nfs4_reclaim_lease(struct nfs_client *clp)
1570 {
1571         struct rpc_cred *cred;
1572         const struct nfs4_state_recovery_ops *ops =
1573                 clp->cl_mvops->reboot_recovery_ops;
1574         int status = -ENOENT;
1575
1576         cred = ops->get_clid_cred(clp);
1577         if (cred != NULL) {
1578                 status = ops->establish_clid(clp, cred);
1579                 put_rpccred(cred);
1580                 /* Handle case where the user hasn't set up machine creds */
1581                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1582                         nfs4_clear_machine_cred(clp);
1583                         status = -EAGAIN;
1584                 }
1585                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1586                         status = -EPROTONOSUPPORT;
1587         }
1588         return status;
1589 }
1590
1591 #ifdef CONFIG_NFS_V4_1
1592 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1593 {
1594         struct nfs_client *clp = session->clp;
1595
1596         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1597         nfs4_schedule_lease_recovery(clp);
1598 }
1599 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1600
1601 void nfs41_handle_recall_slot(struct nfs_client *clp)
1602 {
1603         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1604         nfs4_schedule_state_manager(clp);
1605 }
1606
1607 static void nfs4_reset_all_state(struct nfs_client *clp)
1608 {
1609         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1610                 clp->cl_boot_time = CURRENT_TIME;
1611                 nfs4_state_start_reclaim_nograce(clp);
1612                 nfs4_schedule_state_manager(clp);
1613         }
1614 }
1615
1616 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1617 {
1618         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1619                 nfs4_state_start_reclaim_reboot(clp);
1620                 nfs4_schedule_state_manager(clp);
1621         }
1622 }
1623
1624 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1625 {
1626         /* Temporary */
1627         nfs4_reset_all_state(clp);
1628 }
1629
1630 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1631 {
1632         /* This will need to handle layouts too */
1633         nfs_expire_all_delegations(clp);
1634 }
1635
1636 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1637 {
1638         nfs_expire_all_delegations(clp);
1639         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1640                 nfs4_schedule_state_manager(clp);
1641 }
1642
1643 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1644 {
1645         if (!flags)
1646                 return;
1647         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1648                 nfs41_handle_server_reboot(clp);
1649         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1650                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1651                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1652                             SEQ4_STATUS_LEASE_MOVED))
1653                 nfs41_handle_state_revoked(clp);
1654         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1655                 nfs41_handle_recallable_state_revoked(clp);
1656         if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1657                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1658                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1659                 nfs41_handle_cb_path_down(clp);
1660 }
1661
1662 static int nfs4_reset_session(struct nfs_client *clp)
1663 {
1664         int status;
1665
1666         nfs4_begin_drain_session(clp);
1667         status = nfs4_proc_destroy_session(clp->cl_session);
1668         if (status && status != -NFS4ERR_BADSESSION &&
1669             status != -NFS4ERR_DEADSESSION) {
1670                 status = nfs4_recovery_handle_error(clp, status);
1671                 goto out;
1672         }
1673
1674         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1675         status = nfs4_proc_create_session(clp);
1676         if (status) {
1677                 status = nfs4_recovery_handle_error(clp, status);
1678                 goto out;
1679         }
1680         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1681         /* create_session negotiated new slot table */
1682         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1683
1684          /* Let the state manager reestablish state */
1685         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1686                 nfs41_setup_state_renewal(clp);
1687 out:
1688         return status;
1689 }
1690
1691 static int nfs4_recall_slot(struct nfs_client *clp)
1692 {
1693         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1694         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1695         struct nfs4_slot *new, *old;
1696         int i;
1697
1698         nfs4_begin_drain_session(clp);
1699         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1700                       GFP_NOFS);
1701         if (!new)
1702                 return -ENOMEM;
1703
1704         spin_lock(&fc_tbl->slot_tbl_lock);
1705         for (i = 0; i < fc_tbl->target_max_slots; i++)
1706                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1707         old = fc_tbl->slots;
1708         fc_tbl->slots = new;
1709         fc_tbl->max_slots = fc_tbl->target_max_slots;
1710         fc_tbl->target_max_slots = 0;
1711         fc_attrs->max_reqs = fc_tbl->max_slots;
1712         spin_unlock(&fc_tbl->slot_tbl_lock);
1713
1714         kfree(old);
1715         nfs4_end_drain_session(clp);
1716         return 0;
1717 }
1718
1719 #else /* CONFIG_NFS_V4_1 */
1720 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1721 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1722 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1723 #endif /* CONFIG_NFS_V4_1 */
1724
1725 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1726  * on EXCHANGE_ID for v4.1
1727  */
1728 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1729 {
1730         switch (status) {
1731         case -NFS4ERR_CLID_INUSE:
1732         case -NFS4ERR_STALE_CLIENTID:
1733                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1734                 break;
1735         case -NFS4ERR_DELAY:
1736         case -ETIMEDOUT:
1737         case -EAGAIN:
1738                 ssleep(1);
1739                 break;
1740
1741         case -EKEYEXPIRED:
1742                 nfs4_warn_keyexpired(clp->cl_hostname);
1743         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1744                                  * in nfs4_exchange_id */
1745         default:
1746                 return;
1747         }
1748         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1749 }
1750
1751 static void nfs4_state_manager(struct nfs_client *clp)
1752 {
1753         int status = 0;
1754
1755         /* Ensure exclusive access to NFSv4 state */
1756         do {
1757                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1758                         /* We're going to have to re-establish a clientid */
1759                         status = nfs4_reclaim_lease(clp);
1760                         if (status) {
1761                                 nfs4_set_lease_expired(clp, status);
1762                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1763                                                         &clp->cl_state))
1764                                         continue;
1765                                 if (clp->cl_cons_state ==
1766                                                         NFS_CS_SESSION_INITING)
1767                                         nfs_mark_client_ready(clp, status);
1768                                 goto out_error;
1769                         }
1770                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1771
1772                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1773                                                &clp->cl_state))
1774                                 nfs4_state_start_reclaim_nograce(clp);
1775                         else
1776                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1777                                         &clp->cl_state);
1778
1779                         pnfs_destroy_all_layouts(clp);
1780                 }
1781
1782                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1783                         status = nfs4_check_lease(clp);
1784                         if (status < 0)
1785                                 goto out_error;
1786                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1787                                 continue;
1788                 }
1789
1790                 /* Initialize or reset the session */
1791                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1792                    && nfs4_has_session(clp)) {
1793                         status = nfs4_reset_session(clp);
1794                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1795                                 continue;
1796                         if (status < 0)
1797                                 goto out_error;
1798                 }
1799
1800                 /* First recover reboot state... */
1801                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1802                         status = nfs4_do_reclaim(clp,
1803                                 clp->cl_mvops->reboot_recovery_ops);
1804                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1805                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1806                                 continue;
1807                         nfs4_state_end_reclaim_reboot(clp);
1808                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1809                                 continue;
1810                         if (status < 0)
1811                                 goto out_error;
1812                 }
1813
1814                 /* Now recover expired state... */
1815                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1816                         status = nfs4_do_reclaim(clp,
1817                                 clp->cl_mvops->nograce_recovery_ops);
1818                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1819                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1820                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1821                                 continue;
1822                         if (status < 0)
1823                                 goto out_error;
1824                 }
1825
1826                 nfs4_end_drain_session(clp);
1827                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1828                         nfs_client_return_marked_delegations(clp);
1829                         continue;
1830                 }
1831                 /* Recall session slots */
1832                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1833                    && nfs4_has_session(clp)) {
1834                         status = nfs4_recall_slot(clp);
1835                         if (status < 0)
1836                                 goto out_error;
1837                         continue;
1838                 }
1839
1840
1841                 nfs4_clear_state_manager_bit(clp);
1842                 /* Did we race with an attempt to give us more work? */
1843                 if (clp->cl_state == 0)
1844                         break;
1845                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1846                         break;
1847         } while (atomic_read(&clp->cl_count) > 1);
1848         return;
1849 out_error:
1850         pr_warn_ratelimited("NFS: state manager failed on NFSv4 server %s"
1851                         " with error %d\n", clp->cl_hostname, -status);
1852         nfs4_end_drain_session(clp);
1853         nfs4_clear_state_manager_bit(clp);
1854 }
1855
1856 static int nfs4_run_state_manager(void *ptr)
1857 {
1858         struct nfs_client *clp = ptr;
1859
1860         allow_signal(SIGKILL);
1861         nfs4_state_manager(clp);
1862         nfs_put_client(clp);
1863         module_put_and_exit(0);
1864         return 0;
1865 }
1866
1867 /*
1868  * Local variables:
1869  *  c-basic-offset: 8
1870  * End:
1871  */