d685fd4294fba9fd47d13f42d5754ecee7bf09a3
[linux-3.10.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 NFSDBG_FACILITY         NFSDBG_STATE
61
62 #define OPENOWNER_POOL_SIZE     8
63
64 const nfs4_stateid zero_stateid;
65
66 static LIST_HEAD(nfs4_clientid_list);
67
68 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
69 {
70         struct nfs4_setclientid_res clid = {
71                 .clientid = clp->cl_clientid,
72                 .confirm = clp->cl_confirm,
73         };
74         unsigned short port;
75         int status;
76
77         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
78                 goto do_confirm;
79         port = nfs_callback_tcpport;
80         if (clp->cl_addr.ss_family == AF_INET6)
81                 port = nfs_callback_tcpport6;
82
83         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
84         if (status != 0)
85                 goto out;
86         clp->cl_clientid = clid.clientid;
87         clp->cl_confirm = clid.confirm;
88         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
89 do_confirm:
90         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
91         if (status != 0)
92                 goto out;
93         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
94         nfs4_schedule_state_renewal(clp);
95 out:
96         return status;
97 }
98
99 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
100 {
101         struct rpc_cred *cred = NULL;
102
103         if (clp->cl_machine_cred != NULL)
104                 cred = get_rpccred(clp->cl_machine_cred);
105         return cred;
106 }
107
108 static void nfs4_clear_machine_cred(struct nfs_client *clp)
109 {
110         struct rpc_cred *cred;
111
112         spin_lock(&clp->cl_lock);
113         cred = clp->cl_machine_cred;
114         clp->cl_machine_cred = NULL;
115         spin_unlock(&clp->cl_lock);
116         if (cred != NULL)
117                 put_rpccred(cred);
118 }
119
120 static struct rpc_cred *
121 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
122 {
123         struct rpc_cred *cred = NULL;
124         struct nfs4_state_owner *sp;
125         struct rb_node *pos;
126
127         for (pos = rb_first(&server->state_owners);
128              pos != NULL;
129              pos = rb_next(pos)) {
130                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
131                 if (list_empty(&sp->so_states))
132                         continue;
133                 cred = get_rpccred(sp->so_cred);
134                 break;
135         }
136         return cred;
137 }
138
139 /**
140  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
141  * @clp: client state handle
142  *
143  * Returns an rpc_cred with reference count bumped, or NULL.
144  * Caller must hold clp->cl_lock.
145  */
146 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
147 {
148         struct rpc_cred *cred = NULL;
149         struct nfs_server *server;
150
151         /* Use machine credentials if available */
152         cred = nfs4_get_machine_cred_locked(clp);
153         if (cred != NULL)
154                 goto out;
155
156         rcu_read_lock();
157         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
158                 cred = nfs4_get_renew_cred_server_locked(server);
159                 if (cred != NULL)
160                         break;
161         }
162         rcu_read_unlock();
163
164 out:
165         return cred;
166 }
167
168 #if defined(CONFIG_NFS_V4_1)
169
170 static int nfs41_setup_state_renewal(struct nfs_client *clp)
171 {
172         int status;
173         struct nfs_fsinfo fsinfo;
174
175         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
176                 nfs4_schedule_state_renewal(clp);
177                 return 0;
178         }
179
180         status = nfs4_proc_get_lease_time(clp, &fsinfo);
181         if (status == 0) {
182                 /* Update lease time and schedule renewal */
183                 spin_lock(&clp->cl_lock);
184                 clp->cl_lease_time = fsinfo.lease_time * HZ;
185                 clp->cl_last_renewal = jiffies;
186                 spin_unlock(&clp->cl_lock);
187
188                 nfs4_schedule_state_renewal(clp);
189         }
190
191         return status;
192 }
193
194 /*
195  * Back channel returns NFS4ERR_DELAY for new requests when
196  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
197  * is ended.
198  */
199 static void nfs4_end_drain_session(struct nfs_client *clp)
200 {
201         struct nfs4_session *ses = clp->cl_session;
202         struct nfs4_slot_table *tbl;
203         int max_slots;
204
205         if (ses == NULL)
206                 return;
207         tbl = &ses->fc_slot_table;
208         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
209                 spin_lock(&tbl->slot_tbl_lock);
210                 max_slots = tbl->max_slots;
211                 while (max_slots--) {
212                         if (rpc_wake_up_first(&tbl->slot_tbl_waitq,
213                                                 nfs4_set_task_privileged,
214                                                 NULL) == NULL)
215                                 break;
216                 }
217                 spin_unlock(&tbl->slot_tbl_lock);
218         }
219 }
220
221 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
222 {
223         spin_lock(&tbl->slot_tbl_lock);
224         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
225                 INIT_COMPLETION(tbl->complete);
226                 spin_unlock(&tbl->slot_tbl_lock);
227                 return wait_for_completion_interruptible(&tbl->complete);
228         }
229         spin_unlock(&tbl->slot_tbl_lock);
230         return 0;
231 }
232
233 static int nfs4_begin_drain_session(struct nfs_client *clp)
234 {
235         struct nfs4_session *ses = clp->cl_session;
236         int ret = 0;
237
238         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
239         /* back channel */
240         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
241         if (ret)
242                 return ret;
243         /* fore channel */
244         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
245 }
246
247 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
248 {
249         int status;
250
251         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
252                 goto do_confirm;
253         nfs4_begin_drain_session(clp);
254         status = nfs4_proc_exchange_id(clp, cred);
255         if (status != 0)
256                 goto out;
257         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
258 do_confirm:
259         status = nfs4_proc_create_session(clp, cred);
260         if (status != 0)
261                 goto out;
262         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
263         nfs41_setup_state_renewal(clp);
264         nfs_mark_client_ready(clp, NFS_CS_READY);
265 out:
266         return status;
267 }
268
269 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
270 {
271         struct rpc_cred *cred;
272
273         spin_lock(&clp->cl_lock);
274         cred = nfs4_get_machine_cred_locked(clp);
275         spin_unlock(&clp->cl_lock);
276         return cred;
277 }
278
279 #endif /* CONFIG_NFS_V4_1 */
280
281 static struct rpc_cred *
282 nfs4_get_setclientid_cred_server(struct nfs_server *server)
283 {
284         struct nfs_client *clp = server->nfs_client;
285         struct rpc_cred *cred = NULL;
286         struct nfs4_state_owner *sp;
287         struct rb_node *pos;
288
289         spin_lock(&clp->cl_lock);
290         pos = rb_first(&server->state_owners);
291         if (pos != NULL) {
292                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
293                 cred = get_rpccred(sp->so_cred);
294         }
295         spin_unlock(&clp->cl_lock);
296         return cred;
297 }
298
299 /**
300  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
301  * @clp: client state handle
302  *
303  * Returns an rpc_cred with reference count bumped, or NULL.
304  */
305 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
306 {
307         struct nfs_server *server;
308         struct rpc_cred *cred;
309
310         spin_lock(&clp->cl_lock);
311         cred = nfs4_get_machine_cred_locked(clp);
312         spin_unlock(&clp->cl_lock);
313         if (cred != NULL)
314                 goto out;
315
316         rcu_read_lock();
317         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
318                 cred = nfs4_get_setclientid_cred_server(server);
319                 if (cred != NULL)
320                         break;
321         }
322         rcu_read_unlock();
323
324 out:
325         return cred;
326 }
327
328 static struct nfs4_state_owner *
329 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
330 {
331         struct rb_node **p = &server->state_owners.rb_node,
332                        *parent = NULL;
333         struct nfs4_state_owner *sp;
334
335         while (*p != NULL) {
336                 parent = *p;
337                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
338
339                 if (cred < sp->so_cred)
340                         p = &parent->rb_left;
341                 else if (cred > sp->so_cred)
342                         p = &parent->rb_right;
343                 else {
344                         if (!list_empty(&sp->so_lru))
345                                 list_del_init(&sp->so_lru);
346                         atomic_inc(&sp->so_count);
347                         return sp;
348                 }
349         }
350         return NULL;
351 }
352
353 static struct nfs4_state_owner *
354 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
355 {
356         struct nfs_server *server = new->so_server;
357         struct rb_node **p = &server->state_owners.rb_node,
358                        *parent = NULL;
359         struct nfs4_state_owner *sp;
360         int err;
361
362         while (*p != NULL) {
363                 parent = *p;
364                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
365
366                 if (new->so_cred < sp->so_cred)
367                         p = &parent->rb_left;
368                 else if (new->so_cred > sp->so_cred)
369                         p = &parent->rb_right;
370                 else {
371                         if (!list_empty(&sp->so_lru))
372                                 list_del_init(&sp->so_lru);
373                         atomic_inc(&sp->so_count);
374                         return sp;
375                 }
376         }
377         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
378         if (err)
379                 return ERR_PTR(err);
380         rb_link_node(&new->so_server_node, parent, p);
381         rb_insert_color(&new->so_server_node, &server->state_owners);
382         return new;
383 }
384
385 static void
386 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
387 {
388         struct nfs_server *server = sp->so_server;
389
390         if (!RB_EMPTY_NODE(&sp->so_server_node))
391                 rb_erase(&sp->so_server_node, &server->state_owners);
392         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
393 }
394
395 static void
396 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
397 {
398         sc->create_time = ktime_get();
399         sc->flags = 0;
400         sc->counter = 0;
401         spin_lock_init(&sc->lock);
402         INIT_LIST_HEAD(&sc->list);
403         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
404 }
405
406 static void
407 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
408 {
409         rpc_destroy_wait_queue(&sc->wait);
410 }
411
412 /*
413  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
414  * create a new state_owner.
415  *
416  */
417 static struct nfs4_state_owner *
418 nfs4_alloc_state_owner(struct nfs_server *server,
419                 struct rpc_cred *cred,
420                 gfp_t gfp_flags)
421 {
422         struct nfs4_state_owner *sp;
423
424         sp = kzalloc(sizeof(*sp), gfp_flags);
425         if (!sp)
426                 return NULL;
427         sp->so_server = server;
428         sp->so_cred = get_rpccred(cred);
429         spin_lock_init(&sp->so_lock);
430         INIT_LIST_HEAD(&sp->so_states);
431         nfs4_init_seqid_counter(&sp->so_seqid);
432         atomic_set(&sp->so_count, 1);
433         INIT_LIST_HEAD(&sp->so_lru);
434         return sp;
435 }
436
437 static void
438 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
439 {
440         struct rb_node *rb_node = &sp->so_server_node;
441
442         if (!RB_EMPTY_NODE(rb_node)) {
443                 struct nfs_server *server = sp->so_server;
444                 struct nfs_client *clp = server->nfs_client;
445
446                 spin_lock(&clp->cl_lock);
447                 if (!RB_EMPTY_NODE(rb_node)) {
448                         rb_erase(rb_node, &server->state_owners);
449                         RB_CLEAR_NODE(rb_node);
450                 }
451                 spin_unlock(&clp->cl_lock);
452         }
453 }
454
455 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
456 {
457         nfs4_destroy_seqid_counter(&sp->so_seqid);
458         put_rpccred(sp->so_cred);
459         kfree(sp);
460 }
461
462 static void nfs4_gc_state_owners(struct nfs_server *server)
463 {
464         struct nfs_client *clp = server->nfs_client;
465         struct nfs4_state_owner *sp, *tmp;
466         unsigned long time_min, time_max;
467         LIST_HEAD(doomed);
468
469         spin_lock(&clp->cl_lock);
470         time_max = jiffies;
471         time_min = (long)time_max - (long)clp->cl_lease_time;
472         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
473                 /* NB: LRU is sorted so that oldest is at the head */
474                 if (time_in_range(sp->so_expires, time_min, time_max))
475                         break;
476                 list_move(&sp->so_lru, &doomed);
477                 nfs4_remove_state_owner_locked(sp);
478         }
479         spin_unlock(&clp->cl_lock);
480
481         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
482                 list_del(&sp->so_lru);
483                 nfs4_free_state_owner(sp);
484         }
485 }
486
487 /**
488  * nfs4_get_state_owner - Look up a state owner given a credential
489  * @server: nfs_server to search
490  * @cred: RPC credential to match
491  *
492  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
493  */
494 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
495                                               struct rpc_cred *cred,
496                                               gfp_t gfp_flags)
497 {
498         struct nfs_client *clp = server->nfs_client;
499         struct nfs4_state_owner *sp, *new;
500
501         spin_lock(&clp->cl_lock);
502         sp = nfs4_find_state_owner_locked(server, cred);
503         spin_unlock(&clp->cl_lock);
504         if (sp != NULL)
505                 goto out;
506         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
507         if (new == NULL)
508                 goto out;
509         do {
510                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
511                         break;
512                 spin_lock(&clp->cl_lock);
513                 sp = nfs4_insert_state_owner_locked(new);
514                 spin_unlock(&clp->cl_lock);
515         } while (sp == ERR_PTR(-EAGAIN));
516         if (sp != new)
517                 nfs4_free_state_owner(new);
518 out:
519         nfs4_gc_state_owners(server);
520         return sp;
521 }
522
523 /**
524  * nfs4_put_state_owner - Release a nfs4_state_owner
525  * @sp: state owner data to release
526  *
527  * Note that we keep released state owners on an LRU
528  * list.
529  * This caches valid state owners so that they can be
530  * reused, to avoid the OPEN_CONFIRM on minor version 0.
531  * It also pins the uniquifier of dropped state owners for
532  * a while, to ensure that those state owner names are
533  * never reused.
534  */
535 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
536 {
537         struct nfs_server *server = sp->so_server;
538         struct nfs_client *clp = server->nfs_client;
539
540         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
541                 return;
542
543         sp->so_expires = jiffies;
544         list_add_tail(&sp->so_lru, &server->state_owners_lru);
545         spin_unlock(&clp->cl_lock);
546 }
547
548 /**
549  * nfs4_purge_state_owners - Release all cached state owners
550  * @server: nfs_server with cached state owners to release
551  *
552  * Called at umount time.  Remaining state owners will be on
553  * the LRU with ref count of zero.
554  */
555 void nfs4_purge_state_owners(struct nfs_server *server)
556 {
557         struct nfs_client *clp = server->nfs_client;
558         struct nfs4_state_owner *sp, *tmp;
559         LIST_HEAD(doomed);
560
561         spin_lock(&clp->cl_lock);
562         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
563                 list_move(&sp->so_lru, &doomed);
564                 nfs4_remove_state_owner_locked(sp);
565         }
566         spin_unlock(&clp->cl_lock);
567
568         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
569                 list_del(&sp->so_lru);
570                 nfs4_free_state_owner(sp);
571         }
572 }
573
574 static struct nfs4_state *
575 nfs4_alloc_open_state(void)
576 {
577         struct nfs4_state *state;
578
579         state = kzalloc(sizeof(*state), GFP_NOFS);
580         if (!state)
581                 return NULL;
582         atomic_set(&state->count, 1);
583         INIT_LIST_HEAD(&state->lock_states);
584         spin_lock_init(&state->state_lock);
585         seqlock_init(&state->seqlock);
586         return state;
587 }
588
589 void
590 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
591 {
592         if (state->state == fmode)
593                 return;
594         /* NB! List reordering - see the reclaim code for why.  */
595         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
596                 if (fmode & FMODE_WRITE)
597                         list_move(&state->open_states, &state->owner->so_states);
598                 else
599                         list_move_tail(&state->open_states, &state->owner->so_states);
600         }
601         state->state = fmode;
602 }
603
604 static struct nfs4_state *
605 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
606 {
607         struct nfs_inode *nfsi = NFS_I(inode);
608         struct nfs4_state *state;
609
610         list_for_each_entry(state, &nfsi->open_states, inode_states) {
611                 if (state->owner != owner)
612                         continue;
613                 if (atomic_inc_not_zero(&state->count))
614                         return state;
615         }
616         return NULL;
617 }
618
619 static void
620 nfs4_free_open_state(struct nfs4_state *state)
621 {
622         kfree(state);
623 }
624
625 struct nfs4_state *
626 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
627 {
628         struct nfs4_state *state, *new;
629         struct nfs_inode *nfsi = NFS_I(inode);
630
631         spin_lock(&inode->i_lock);
632         state = __nfs4_find_state_byowner(inode, owner);
633         spin_unlock(&inode->i_lock);
634         if (state)
635                 goto out;
636         new = nfs4_alloc_open_state();
637         spin_lock(&owner->so_lock);
638         spin_lock(&inode->i_lock);
639         state = __nfs4_find_state_byowner(inode, owner);
640         if (state == NULL && new != NULL) {
641                 state = new;
642                 state->owner = owner;
643                 atomic_inc(&owner->so_count);
644                 list_add(&state->inode_states, &nfsi->open_states);
645                 ihold(inode);
646                 state->inode = inode;
647                 spin_unlock(&inode->i_lock);
648                 /* Note: The reclaim code dictates that we add stateless
649                  * and read-only stateids to the end of the list */
650                 list_add_tail(&state->open_states, &owner->so_states);
651                 spin_unlock(&owner->so_lock);
652         } else {
653                 spin_unlock(&inode->i_lock);
654                 spin_unlock(&owner->so_lock);
655                 if (new)
656                         nfs4_free_open_state(new);
657         }
658 out:
659         return state;
660 }
661
662 void nfs4_put_open_state(struct nfs4_state *state)
663 {
664         struct inode *inode = state->inode;
665         struct nfs4_state_owner *owner = state->owner;
666
667         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
668                 return;
669         spin_lock(&inode->i_lock);
670         list_del(&state->inode_states);
671         list_del(&state->open_states);
672         spin_unlock(&inode->i_lock);
673         spin_unlock(&owner->so_lock);
674         iput(inode);
675         nfs4_free_open_state(state);
676         nfs4_put_state_owner(owner);
677 }
678
679 /*
680  * Close the current file.
681  */
682 static void __nfs4_close(struct nfs4_state *state,
683                 fmode_t fmode, gfp_t gfp_mask, int wait)
684 {
685         struct nfs4_state_owner *owner = state->owner;
686         int call_close = 0;
687         fmode_t newstate;
688
689         atomic_inc(&owner->so_count);
690         /* Protect against nfs4_find_state() */
691         spin_lock(&owner->so_lock);
692         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
693                 case FMODE_READ:
694                         state->n_rdonly--;
695                         break;
696                 case FMODE_WRITE:
697                         state->n_wronly--;
698                         break;
699                 case FMODE_READ|FMODE_WRITE:
700                         state->n_rdwr--;
701         }
702         newstate = FMODE_READ|FMODE_WRITE;
703         if (state->n_rdwr == 0) {
704                 if (state->n_rdonly == 0) {
705                         newstate &= ~FMODE_READ;
706                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
707                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
708                 }
709                 if (state->n_wronly == 0) {
710                         newstate &= ~FMODE_WRITE;
711                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
712                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
713                 }
714                 if (newstate == 0)
715                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
716         }
717         nfs4_state_set_mode_locked(state, newstate);
718         spin_unlock(&owner->so_lock);
719
720         if (!call_close) {
721                 nfs4_put_open_state(state);
722                 nfs4_put_state_owner(owner);
723         } else {
724                 bool roc = pnfs_roc(state->inode);
725
726                 nfs4_do_close(state, gfp_mask, wait, roc);
727         }
728 }
729
730 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
731 {
732         __nfs4_close(state, fmode, GFP_NOFS, 0);
733 }
734
735 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
736 {
737         __nfs4_close(state, fmode, GFP_KERNEL, 1);
738 }
739
740 /*
741  * Search the state->lock_states for an existing lock_owner
742  * that is compatible with current->files
743  */
744 static struct nfs4_lock_state *
745 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
746 {
747         struct nfs4_lock_state *pos;
748         list_for_each_entry(pos, &state->lock_states, ls_locks) {
749                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
750                         continue;
751                 switch (pos->ls_owner.lo_type) {
752                 case NFS4_POSIX_LOCK_TYPE:
753                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
754                                 continue;
755                         break;
756                 case NFS4_FLOCK_LOCK_TYPE:
757                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
758                                 continue;
759                 }
760                 atomic_inc(&pos->ls_count);
761                 return pos;
762         }
763         return NULL;
764 }
765
766 /*
767  * Return a compatible lock_state. If no initialized lock_state structure
768  * exists, return an uninitialized one.
769  *
770  */
771 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)
772 {
773         struct nfs4_lock_state *lsp;
774         struct nfs_server *server = state->owner->so_server;
775
776         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
777         if (lsp == NULL)
778                 return NULL;
779         nfs4_init_seqid_counter(&lsp->ls_seqid);
780         atomic_set(&lsp->ls_count, 1);
781         lsp->ls_state = state;
782         lsp->ls_owner.lo_type = type;
783         switch (lsp->ls_owner.lo_type) {
784         case NFS4_FLOCK_LOCK_TYPE:
785                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
786                 break;
787         case NFS4_POSIX_LOCK_TYPE:
788                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
789                 break;
790         default:
791                 goto out_free;
792         }
793         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
794         if (lsp->ls_seqid.owner_id < 0)
795                 goto out_free;
796         INIT_LIST_HEAD(&lsp->ls_locks);
797         return lsp;
798 out_free:
799         kfree(lsp);
800         return NULL;
801 }
802
803 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
804 {
805         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
806         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
807         kfree(lsp);
808 }
809
810 /*
811  * Return a compatible lock_state. If no initialized lock_state structure
812  * exists, return an uninitialized one.
813  *
814  */
815 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
816 {
817         struct nfs4_lock_state *lsp, *new = NULL;
818         
819         for(;;) {
820                 spin_lock(&state->state_lock);
821                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
822                 if (lsp != NULL)
823                         break;
824                 if (new != NULL) {
825                         list_add(&new->ls_locks, &state->lock_states);
826                         set_bit(LK_STATE_IN_USE, &state->flags);
827                         lsp = new;
828                         new = NULL;
829                         break;
830                 }
831                 spin_unlock(&state->state_lock);
832                 new = nfs4_alloc_lock_state(state, owner, pid, type);
833                 if (new == NULL)
834                         return NULL;
835         }
836         spin_unlock(&state->state_lock);
837         if (new != NULL)
838                 nfs4_free_lock_state(state->owner->so_server, new);
839         return lsp;
840 }
841
842 /*
843  * Release reference to lock_state, and free it if we see that
844  * it is no longer in use
845  */
846 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
847 {
848         struct nfs4_state *state;
849
850         if (lsp == NULL)
851                 return;
852         state = lsp->ls_state;
853         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
854                 return;
855         list_del(&lsp->ls_locks);
856         if (list_empty(&state->lock_states))
857                 clear_bit(LK_STATE_IN_USE, &state->flags);
858         spin_unlock(&state->state_lock);
859         if (lsp->ls_flags & NFS_LOCK_INITIALIZED) {
860                 if (nfs4_release_lockowner(lsp) == 0)
861                         return;
862         }
863         nfs4_free_lock_state(lsp->ls_state->owner->so_server, lsp);
864 }
865
866 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
867 {
868         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
869
870         dst->fl_u.nfs4_fl.owner = lsp;
871         atomic_inc(&lsp->ls_count);
872 }
873
874 static void nfs4_fl_release_lock(struct file_lock *fl)
875 {
876         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
877 }
878
879 static const struct file_lock_operations nfs4_fl_lock_ops = {
880         .fl_copy_lock = nfs4_fl_copy_lock,
881         .fl_release_private = nfs4_fl_release_lock,
882 };
883
884 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
885 {
886         struct nfs4_lock_state *lsp;
887
888         if (fl->fl_ops != NULL)
889                 return 0;
890         if (fl->fl_flags & FL_POSIX)
891                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
892         else if (fl->fl_flags & FL_FLOCK)
893                 lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
894                                 NFS4_FLOCK_LOCK_TYPE);
895         else
896                 return -EINVAL;
897         if (lsp == NULL)
898                 return -ENOMEM;
899         fl->fl_u.nfs4_fl.owner = lsp;
900         fl->fl_ops = &nfs4_fl_lock_ops;
901         return 0;
902 }
903
904 static bool nfs4_copy_lock_stateid(nfs4_stateid *dst, struct nfs4_state *state,
905                 fl_owner_t fl_owner, pid_t fl_pid)
906 {
907         struct nfs4_lock_state *lsp;
908         bool ret = false;
909
910         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
911                 goto out;
912
913         spin_lock(&state->state_lock);
914         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
915         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0) {
916                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
917                 ret = true;
918         }
919         spin_unlock(&state->state_lock);
920         nfs4_put_lock_state(lsp);
921 out:
922         return ret;
923 }
924
925 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
926 {
927         int seq;
928
929         do {
930                 seq = read_seqbegin(&state->seqlock);
931                 nfs4_stateid_copy(dst, &state->stateid);
932         } while (read_seqretry(&state->seqlock, seq));
933 }
934
935 /*
936  * Byte-range lock aware utility to initialize the stateid of read/write
937  * requests.
938  */
939 void nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
940                 fmode_t fmode, fl_owner_t fl_owner, pid_t fl_pid)
941 {
942         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
943                 return;
944         if (nfs4_copy_lock_stateid(dst, state, fl_owner, fl_pid))
945                 return;
946         nfs4_copy_open_stateid(dst, state);
947 }
948
949 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
950 {
951         struct nfs_seqid *new;
952
953         new = kmalloc(sizeof(*new), gfp_mask);
954         if (new != NULL) {
955                 new->sequence = counter;
956                 INIT_LIST_HEAD(&new->list);
957                 new->task = NULL;
958         }
959         return new;
960 }
961
962 void nfs_release_seqid(struct nfs_seqid *seqid)
963 {
964         struct nfs_seqid_counter *sequence;
965
966         if (list_empty(&seqid->list))
967                 return;
968         sequence = seqid->sequence;
969         spin_lock(&sequence->lock);
970         list_del_init(&seqid->list);
971         if (!list_empty(&sequence->list)) {
972                 struct nfs_seqid *next;
973
974                 next = list_first_entry(&sequence->list,
975                                 struct nfs_seqid, list);
976                 rpc_wake_up_queued_task(&sequence->wait, next->task);
977         }
978         spin_unlock(&sequence->lock);
979 }
980
981 void nfs_free_seqid(struct nfs_seqid *seqid)
982 {
983         nfs_release_seqid(seqid);
984         kfree(seqid);
985 }
986
987 /*
988  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
989  * failed with a seqid incrementing error -
990  * see comments nfs_fs.h:seqid_mutating_error()
991  */
992 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
993 {
994         BUG_ON(list_first_entry(&seqid->sequence->list, struct nfs_seqid, list) != seqid);
995         switch (status) {
996                 case 0:
997                         break;
998                 case -NFS4ERR_BAD_SEQID:
999                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1000                                 return;
1001                         pr_warn_ratelimited("NFS: v4 server returned a bad"
1002                                         " sequence-id error on an"
1003                                         " unconfirmed sequence %p!\n",
1004                                         seqid->sequence);
1005                 case -NFS4ERR_STALE_CLIENTID:
1006                 case -NFS4ERR_STALE_STATEID:
1007                 case -NFS4ERR_BAD_STATEID:
1008                 case -NFS4ERR_BADXDR:
1009                 case -NFS4ERR_RESOURCE:
1010                 case -NFS4ERR_NOFILEHANDLE:
1011                         /* Non-seqid mutating errors */
1012                         return;
1013         };
1014         /*
1015          * Note: no locking needed as we are guaranteed to be first
1016          * on the sequence list
1017          */
1018         seqid->sequence->counter++;
1019 }
1020
1021 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1022 {
1023         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1024                                         struct nfs4_state_owner, so_seqid);
1025         struct nfs_server *server = sp->so_server;
1026
1027         if (status == -NFS4ERR_BAD_SEQID)
1028                 nfs4_drop_state_owner(sp);
1029         if (!nfs4_has_session(server->nfs_client))
1030                 nfs_increment_seqid(status, seqid);
1031 }
1032
1033 /*
1034  * Increment the seqid if the LOCK/LOCKU succeeded, or
1035  * failed with a seqid incrementing error -
1036  * see comments nfs_fs.h:seqid_mutating_error()
1037  */
1038 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1039 {
1040         nfs_increment_seqid(status, seqid);
1041 }
1042
1043 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1044 {
1045         struct nfs_seqid_counter *sequence = seqid->sequence;
1046         int status = 0;
1047
1048         spin_lock(&sequence->lock);
1049         seqid->task = task;
1050         if (list_empty(&seqid->list))
1051                 list_add_tail(&seqid->list, &sequence->list);
1052         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1053                 goto unlock;
1054         rpc_sleep_on(&sequence->wait, task, NULL);
1055         status = -EAGAIN;
1056 unlock:
1057         spin_unlock(&sequence->lock);
1058         return status;
1059 }
1060
1061 static int nfs4_run_state_manager(void *);
1062
1063 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1064 {
1065         smp_mb__before_clear_bit();
1066         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1067         smp_mb__after_clear_bit();
1068         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1069         rpc_wake_up(&clp->cl_rpcwaitq);
1070 }
1071
1072 /*
1073  * Schedule the nfs_client asynchronous state management routine
1074  */
1075 void nfs4_schedule_state_manager(struct nfs_client *clp)
1076 {
1077         struct task_struct *task;
1078         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1079
1080         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1081                 return;
1082         __module_get(THIS_MODULE);
1083         atomic_inc(&clp->cl_count);
1084
1085         /* The rcu_read_lock() is not strictly necessary, as the state
1086          * manager is the only thread that ever changes the rpc_xprt
1087          * after it's initialized.  At this point, we're single threaded. */
1088         rcu_read_lock();
1089         snprintf(buf, sizeof(buf), "%s-manager",
1090                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1091         rcu_read_unlock();
1092         task = kthread_run(nfs4_run_state_manager, clp, buf);
1093         if (IS_ERR(task)) {
1094                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1095                         __func__, PTR_ERR(task));
1096                 nfs4_clear_state_manager_bit(clp);
1097                 nfs_put_client(clp);
1098                 module_put(THIS_MODULE);
1099         }
1100 }
1101
1102 /*
1103  * Schedule a lease recovery attempt
1104  */
1105 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1106 {
1107         if (!clp)
1108                 return;
1109         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1110                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1111         nfs4_schedule_state_manager(clp);
1112 }
1113 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1114
1115 /*
1116  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1117  * @clp: client to process
1118  *
1119  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1120  * resend of the SETCLIENTID and hence re-establish the
1121  * callback channel. Then return all existing delegations.
1122  */
1123 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1124 {
1125         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1126         nfs_expire_all_delegations(clp);
1127 }
1128
1129 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1130 {
1131         nfs40_handle_cb_pathdown(clp);
1132         nfs4_schedule_state_manager(clp);
1133 }
1134
1135 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1136 {
1137
1138         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1139         /* Don't recover state that expired before the reboot */
1140         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1141                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1142                 return 0;
1143         }
1144         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1145         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1146         return 1;
1147 }
1148
1149 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1150 {
1151         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1152         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1153         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1154         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1155         return 1;
1156 }
1157
1158 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1159 {
1160         struct nfs_client *clp = server->nfs_client;
1161
1162         nfs4_state_mark_reclaim_nograce(clp, state);
1163         nfs4_schedule_state_manager(clp);
1164 }
1165 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1166
1167 void nfs_inode_find_state_and_recover(struct inode *inode,
1168                 const nfs4_stateid *stateid)
1169 {
1170         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1171         struct nfs_inode *nfsi = NFS_I(inode);
1172         struct nfs_open_context *ctx;
1173         struct nfs4_state *state;
1174         bool found = false;
1175
1176         spin_lock(&inode->i_lock);
1177         list_for_each_entry(ctx, &nfsi->open_files, list) {
1178                 state = ctx->state;
1179                 if (state == NULL)
1180                         continue;
1181                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1182                         continue;
1183                 if (!nfs4_stateid_match(&state->stateid, stateid))
1184                         continue;
1185                 nfs4_state_mark_reclaim_nograce(clp, state);
1186                 found = true;
1187         }
1188         spin_unlock(&inode->i_lock);
1189         if (found)
1190                 nfs4_schedule_state_manager(clp);
1191 }
1192
1193
1194 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1195 {
1196         struct inode *inode = state->inode;
1197         struct nfs_inode *nfsi = NFS_I(inode);
1198         struct file_lock *fl;
1199         int status = 0;
1200
1201         if (inode->i_flock == NULL)
1202                 return 0;
1203
1204         /* Guard against delegation returns and new lock/unlock calls */
1205         down_write(&nfsi->rwsem);
1206         /* Protect inode->i_flock using the BKL */
1207         lock_flocks();
1208         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1209                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1210                         continue;
1211                 if (nfs_file_open_context(fl->fl_file)->state != state)
1212                         continue;
1213                 unlock_flocks();
1214                 status = ops->recover_lock(state, fl);
1215                 switch (status) {
1216                         case 0:
1217                                 break;
1218                         case -ESTALE:
1219                         case -NFS4ERR_ADMIN_REVOKED:
1220                         case -NFS4ERR_STALE_STATEID:
1221                         case -NFS4ERR_BAD_STATEID:
1222                         case -NFS4ERR_EXPIRED:
1223                         case -NFS4ERR_NO_GRACE:
1224                         case -NFS4ERR_STALE_CLIENTID:
1225                         case -NFS4ERR_BADSESSION:
1226                         case -NFS4ERR_BADSLOT:
1227                         case -NFS4ERR_BAD_HIGH_SLOT:
1228                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1229                                 goto out;
1230                         default:
1231                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1232                                         "Zeroing state\n", __func__, status);
1233                         case -ENOMEM:
1234                         case -NFS4ERR_DENIED:
1235                         case -NFS4ERR_RECLAIM_BAD:
1236                         case -NFS4ERR_RECLAIM_CONFLICT:
1237                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1238                                 status = 0;
1239                 }
1240                 lock_flocks();
1241         }
1242         unlock_flocks();
1243 out:
1244         up_write(&nfsi->rwsem);
1245         return status;
1246 }
1247
1248 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1249 {
1250         struct nfs4_state *state;
1251         struct nfs4_lock_state *lock;
1252         int status = 0;
1253
1254         /* Note: we rely on the sp->so_states list being ordered 
1255          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1256          * states first.
1257          * This is needed to ensure that the server won't give us any
1258          * read delegations that we have to return if, say, we are
1259          * recovering after a network partition or a reboot from a
1260          * server that doesn't support a grace period.
1261          */
1262 restart:
1263         spin_lock(&sp->so_lock);
1264         list_for_each_entry(state, &sp->so_states, open_states) {
1265                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1266                         continue;
1267                 if (state->state == 0)
1268                         continue;
1269                 atomic_inc(&state->count);
1270                 spin_unlock(&sp->so_lock);
1271                 status = ops->recover_open(sp, state);
1272                 if (status >= 0) {
1273                         status = nfs4_reclaim_locks(state, ops);
1274                         if (status >= 0) {
1275                                 spin_lock(&state->state_lock);
1276                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1277                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1278                                                 pr_warn_ratelimited("NFS: "
1279                                                         "%s: Lock reclaim "
1280                                                         "failed!\n", __func__);
1281                                 }
1282                                 spin_unlock(&state->state_lock);
1283                                 nfs4_put_open_state(state);
1284                                 goto restart;
1285                         }
1286                 }
1287                 switch (status) {
1288                         default:
1289                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1290                                         "Zeroing state\n", __func__, status);
1291                         case -ENOENT:
1292                         case -ENOMEM:
1293                         case -ESTALE:
1294                                 /*
1295                                  * Open state on this file cannot be recovered
1296                                  * All we can do is revert to using the zero stateid.
1297                                  */
1298                                 memset(&state->stateid, 0,
1299                                         sizeof(state->stateid));
1300                                 /* Mark the file as being 'closed' */
1301                                 state->state = 0;
1302                                 break;
1303                         case -EKEYEXPIRED:
1304                                 /*
1305                                  * User RPCSEC_GSS context has expired.
1306                                  * We cannot recover this stateid now, so
1307                                  * skip it and allow recovery thread to
1308                                  * proceed.
1309                                  */
1310                                 break;
1311                         case -NFS4ERR_ADMIN_REVOKED:
1312                         case -NFS4ERR_STALE_STATEID:
1313                         case -NFS4ERR_BAD_STATEID:
1314                         case -NFS4ERR_RECLAIM_BAD:
1315                         case -NFS4ERR_RECLAIM_CONFLICT:
1316                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1317                                 break;
1318                         case -NFS4ERR_EXPIRED:
1319                         case -NFS4ERR_NO_GRACE:
1320                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1321                         case -NFS4ERR_STALE_CLIENTID:
1322                         case -NFS4ERR_BADSESSION:
1323                         case -NFS4ERR_BADSLOT:
1324                         case -NFS4ERR_BAD_HIGH_SLOT:
1325                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1326                                 goto out_err;
1327                 }
1328                 nfs4_put_open_state(state);
1329                 goto restart;
1330         }
1331         spin_unlock(&sp->so_lock);
1332         return 0;
1333 out_err:
1334         nfs4_put_open_state(state);
1335         return status;
1336 }
1337
1338 static void nfs4_clear_open_state(struct nfs4_state *state)
1339 {
1340         struct nfs4_lock_state *lock;
1341
1342         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1343         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1344         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1345         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1346         spin_lock(&state->state_lock);
1347         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1348                 lock->ls_seqid.flags = 0;
1349                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1350         }
1351         spin_unlock(&state->state_lock);
1352 }
1353
1354 static void nfs4_reset_seqids(struct nfs_server *server,
1355         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1356 {
1357         struct nfs_client *clp = server->nfs_client;
1358         struct nfs4_state_owner *sp;
1359         struct rb_node *pos;
1360         struct nfs4_state *state;
1361
1362         spin_lock(&clp->cl_lock);
1363         for (pos = rb_first(&server->state_owners);
1364              pos != NULL;
1365              pos = rb_next(pos)) {
1366                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1367                 sp->so_seqid.flags = 0;
1368                 spin_lock(&sp->so_lock);
1369                 list_for_each_entry(state, &sp->so_states, open_states) {
1370                         if (mark_reclaim(clp, state))
1371                                 nfs4_clear_open_state(state);
1372                 }
1373                 spin_unlock(&sp->so_lock);
1374         }
1375         spin_unlock(&clp->cl_lock);
1376 }
1377
1378 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1379         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1380 {
1381         struct nfs_server *server;
1382
1383         rcu_read_lock();
1384         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1385                 nfs4_reset_seqids(server, mark_reclaim);
1386         rcu_read_unlock();
1387 }
1388
1389 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1390 {
1391         /* Mark all delegations for reclaim */
1392         nfs_delegation_mark_reclaim(clp);
1393         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1394 }
1395
1396 static void nfs4_reclaim_complete(struct nfs_client *clp,
1397                                  const struct nfs4_state_recovery_ops *ops)
1398 {
1399         /* Notify the server we're done reclaiming our state */
1400         if (ops->reclaim_complete)
1401                 (void)ops->reclaim_complete(clp);
1402 }
1403
1404 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1405 {
1406         struct nfs_client *clp = server->nfs_client;
1407         struct nfs4_state_owner *sp;
1408         struct rb_node *pos;
1409         struct nfs4_state *state;
1410
1411         spin_lock(&clp->cl_lock);
1412         for (pos = rb_first(&server->state_owners);
1413              pos != NULL;
1414              pos = rb_next(pos)) {
1415                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1416                 spin_lock(&sp->so_lock);
1417                 list_for_each_entry(state, &sp->so_states, open_states) {
1418                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1419                                                 &state->flags))
1420                                 continue;
1421                         nfs4_state_mark_reclaim_nograce(clp, state);
1422                 }
1423                 spin_unlock(&sp->so_lock);
1424         }
1425         spin_unlock(&clp->cl_lock);
1426 }
1427
1428 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1429 {
1430         struct nfs_server *server;
1431
1432         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1433                 return 0;
1434
1435         rcu_read_lock();
1436         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1437                 nfs4_clear_reclaim_server(server);
1438         rcu_read_unlock();
1439
1440         nfs_delegation_reap_unclaimed(clp);
1441         return 1;
1442 }
1443
1444 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1445 {
1446         if (!nfs4_state_clear_reclaim_reboot(clp))
1447                 return;
1448         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1449 }
1450
1451 static void nfs_delegation_clear_all(struct nfs_client *clp)
1452 {
1453         nfs_delegation_mark_reclaim(clp);
1454         nfs_delegation_reap_unclaimed(clp);
1455 }
1456
1457 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1458 {
1459         nfs_delegation_clear_all(clp);
1460         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1461 }
1462
1463 static void nfs4_warn_keyexpired(const char *s)
1464 {
1465         printk_ratelimited(KERN_WARNING "Error: state manager"
1466                         " encountered RPCSEC_GSS session"
1467                         " expired against NFSv4 server %s.\n",
1468                         s);
1469 }
1470
1471 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1472 {
1473         switch (error) {
1474                 case 0:
1475                         break;
1476                 case -NFS4ERR_CB_PATH_DOWN:
1477                         nfs40_handle_cb_pathdown(clp);
1478                         break;
1479                 case -NFS4ERR_NO_GRACE:
1480                         nfs4_state_end_reclaim_reboot(clp);
1481                         break;
1482                 case -NFS4ERR_STALE_CLIENTID:
1483                 case -NFS4ERR_LEASE_MOVED:
1484                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1485                         nfs4_state_clear_reclaim_reboot(clp);
1486                         nfs4_state_start_reclaim_reboot(clp);
1487                         break;
1488                 case -NFS4ERR_EXPIRED:
1489                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1490                         nfs4_state_start_reclaim_nograce(clp);
1491                         break;
1492                 case -NFS4ERR_BADSESSION:
1493                 case -NFS4ERR_BADSLOT:
1494                 case -NFS4ERR_BAD_HIGH_SLOT:
1495                 case -NFS4ERR_DEADSESSION:
1496                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1497                 case -NFS4ERR_SEQ_FALSE_RETRY:
1498                 case -NFS4ERR_SEQ_MISORDERED:
1499                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1500                         /* Zero session reset errors */
1501                         break;
1502                 case -EKEYEXPIRED:
1503                         /* Nothing we can do */
1504                         nfs4_warn_keyexpired(clp->cl_hostname);
1505                         break;
1506                 default:
1507                         return error;
1508         }
1509         return 0;
1510 }
1511
1512 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1513 {
1514         struct nfs4_state_owner *sp;
1515         struct nfs_server *server;
1516         struct rb_node *pos;
1517         int status = 0;
1518
1519 restart:
1520         rcu_read_lock();
1521         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1522                 nfs4_purge_state_owners(server);
1523                 spin_lock(&clp->cl_lock);
1524                 for (pos = rb_first(&server->state_owners);
1525                      pos != NULL;
1526                      pos = rb_next(pos)) {
1527                         sp = rb_entry(pos,
1528                                 struct nfs4_state_owner, so_server_node);
1529                         if (!test_and_clear_bit(ops->owner_flag_bit,
1530                                                         &sp->so_flags))
1531                                 continue;
1532                         atomic_inc(&sp->so_count);
1533                         spin_unlock(&clp->cl_lock);
1534                         rcu_read_unlock();
1535
1536                         status = nfs4_reclaim_open_state(sp, ops);
1537                         if (status < 0) {
1538                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1539                                 nfs4_put_state_owner(sp);
1540                                 return nfs4_recovery_handle_error(clp, status);
1541                         }
1542
1543                         nfs4_put_state_owner(sp);
1544                         goto restart;
1545                 }
1546                 spin_unlock(&clp->cl_lock);
1547         }
1548         rcu_read_unlock();
1549         return status;
1550 }
1551
1552 static int nfs4_check_lease(struct nfs_client *clp)
1553 {
1554         struct rpc_cred *cred;
1555         const struct nfs4_state_maintenance_ops *ops =
1556                 clp->cl_mvops->state_renewal_ops;
1557         int status;
1558
1559         /* Is the client already known to have an expired lease? */
1560         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1561                 return 0;
1562         spin_lock(&clp->cl_lock);
1563         cred = ops->get_state_renewal_cred_locked(clp);
1564         spin_unlock(&clp->cl_lock);
1565         if (cred == NULL) {
1566                 cred = nfs4_get_setclientid_cred(clp);
1567                 status = -ENOKEY;
1568                 if (cred == NULL)
1569                         goto out;
1570         }
1571         status = ops->renew_lease(clp, cred);
1572         put_rpccred(cred);
1573 out:
1574         return nfs4_recovery_handle_error(clp, status);
1575 }
1576
1577 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1578  * on EXCHANGE_ID for v4.1
1579  */
1580 static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
1581 {
1582         switch (status) {
1583         case -NFS4ERR_SEQ_MISORDERED:
1584                 if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
1585                         return -ESERVERFAULT;
1586                 /* Lease confirmation error: retry after purging the lease */
1587                 ssleep(1);
1588         case -NFS4ERR_CLID_INUSE:
1589         case -NFS4ERR_STALE_CLIENTID:
1590                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1591                 break;
1592         case -EACCES:
1593                 if (clp->cl_machine_cred == NULL)
1594                         return -EACCES;
1595                 /* Handle case where the user hasn't set up machine creds */
1596                 nfs4_clear_machine_cred(clp);
1597         case -NFS4ERR_DELAY:
1598         case -ETIMEDOUT:
1599         case -EAGAIN:
1600                 ssleep(1);
1601                 break;
1602
1603         case -NFS4ERR_MINOR_VERS_MISMATCH:
1604                 if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1605                         nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
1606                 return -EPROTONOSUPPORT;
1607         case -EKEYEXPIRED:
1608                 nfs4_warn_keyexpired(clp->cl_hostname);
1609         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1610                                  * in nfs4_exchange_id */
1611         default:
1612                 return status;
1613         }
1614         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1615         return 0;
1616 }
1617
1618 static int nfs4_reclaim_lease(struct nfs_client *clp)
1619 {
1620         struct rpc_cred *cred;
1621         const struct nfs4_state_recovery_ops *ops =
1622                 clp->cl_mvops->reboot_recovery_ops;
1623         int status;
1624
1625         cred = ops->get_clid_cred(clp);
1626         if (cred == NULL)
1627                 return -ENOENT;
1628         status = ops->establish_clid(clp, cred);
1629         put_rpccred(cred);
1630         if (status != 0)
1631                 return nfs4_handle_reclaim_lease_error(clp, status);
1632         return 0;
1633 }
1634
1635 #ifdef CONFIG_NFS_V4_1
1636 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1637 {
1638         struct nfs_client *clp = session->clp;
1639
1640         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1641         nfs4_schedule_lease_recovery(clp);
1642 }
1643 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1644
1645 void nfs41_handle_recall_slot(struct nfs_client *clp)
1646 {
1647         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1648         nfs4_schedule_state_manager(clp);
1649 }
1650
1651 static void nfs4_reset_all_state(struct nfs_client *clp)
1652 {
1653         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1654                 set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1655                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1656                 nfs4_state_start_reclaim_nograce(clp);
1657                 nfs4_schedule_state_manager(clp);
1658         }
1659 }
1660
1661 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1662 {
1663         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1664                 nfs4_state_start_reclaim_reboot(clp);
1665                 nfs4_schedule_state_manager(clp);
1666         }
1667 }
1668
1669 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1670 {
1671         nfs4_reset_all_state(clp);
1672 }
1673
1674 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1675 {
1676         /* This will need to handle layouts too */
1677         nfs_expire_all_delegations(clp);
1678 }
1679
1680 static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
1681 {
1682         nfs_expire_all_delegations(clp);
1683         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1684                 nfs4_schedule_state_manager(clp);
1685 }
1686
1687 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1688 {
1689         if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
1690                 &clp->cl_state) == 0)
1691                 nfs4_schedule_state_manager(clp);
1692 }
1693
1694 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1695 {
1696         if (!flags)
1697                 return;
1698
1699         dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
1700                 __func__, clp->cl_hostname, clp->cl_clientid, flags);
1701
1702         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1703                 nfs41_handle_server_reboot(clp);
1704         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1705                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1706                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1707                             SEQ4_STATUS_LEASE_MOVED))
1708                 nfs41_handle_state_revoked(clp);
1709         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1710                 nfs41_handle_recallable_state_revoked(clp);
1711         if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
1712                 nfs41_handle_backchannel_fault(clp);
1713         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1714                                 SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1715                 nfs41_handle_cb_path_down(clp);
1716 }
1717
1718 static int nfs4_reset_session(struct nfs_client *clp)
1719 {
1720         struct rpc_cred *cred;
1721         int status;
1722
1723         nfs4_begin_drain_session(clp);
1724         cred = nfs4_get_exchange_id_cred(clp);
1725         status = nfs4_proc_destroy_session(clp->cl_session, cred);
1726         if (status && status != -NFS4ERR_BADSESSION &&
1727             status != -NFS4ERR_DEADSESSION) {
1728                 status = nfs4_recovery_handle_error(clp, status);
1729                 goto out;
1730         }
1731
1732         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1733         status = nfs4_proc_create_session(clp, cred);
1734         if (status) {
1735                 status = nfs4_recovery_handle_error(clp, status);
1736                 goto out;
1737         }
1738         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1739         /* create_session negotiated new slot table */
1740         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1741         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1742
1743          /* Let the state manager reestablish state */
1744         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1745                 nfs41_setup_state_renewal(clp);
1746 out:
1747         if (cred)
1748                 put_rpccred(cred);
1749         return status;
1750 }
1751
1752 static int nfs4_recall_slot(struct nfs_client *clp)
1753 {
1754         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1755         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1756         struct nfs4_slot *new, *old;
1757         int i;
1758
1759         nfs4_begin_drain_session(clp);
1760         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1761                       GFP_NOFS);
1762         if (!new)
1763                 return -ENOMEM;
1764
1765         spin_lock(&fc_tbl->slot_tbl_lock);
1766         for (i = 0; i < fc_tbl->target_max_slots; i++)
1767                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1768         old = fc_tbl->slots;
1769         fc_tbl->slots = new;
1770         fc_tbl->max_slots = fc_tbl->target_max_slots;
1771         fc_tbl->target_max_slots = 0;
1772         fc_attrs->max_reqs = fc_tbl->max_slots;
1773         spin_unlock(&fc_tbl->slot_tbl_lock);
1774
1775         kfree(old);
1776         nfs4_end_drain_session(clp);
1777         return 0;
1778 }
1779
1780 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
1781 {
1782         struct rpc_cred *cred;
1783         int ret;
1784
1785         nfs4_begin_drain_session(clp);
1786         cred = nfs4_get_exchange_id_cred(clp);
1787         ret = nfs4_proc_bind_conn_to_session(clp, cred);
1788         if (cred)
1789                 put_rpccred(cred);
1790         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1791         switch (ret) {
1792         case 0:
1793                 break;
1794         case -NFS4ERR_DELAY:
1795                 ssleep(1);
1796                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1797                 break;
1798         default:
1799                 return nfs4_recovery_handle_error(clp, ret);
1800         }
1801         return 0;
1802 }
1803 #else /* CONFIG_NFS_V4_1 */
1804 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1805 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1806 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1807
1808 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
1809 {
1810         return 0;
1811 }
1812 #endif /* CONFIG_NFS_V4_1 */
1813
1814 static void nfs4_state_manager(struct nfs_client *clp)
1815 {
1816         int status = 0;
1817
1818         /* Ensure exclusive access to NFSv4 state */
1819         do {
1820                 if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
1821                         status = nfs4_reclaim_lease(clp);
1822                         if (status < 0)
1823                                 goto out_error;
1824                         clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1825                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1826                 }
1827
1828                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1829                         /* We're going to have to re-establish a clientid */
1830                         status = nfs4_reclaim_lease(clp);
1831                         if (status < 0)
1832                                 goto out_error;
1833                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1834                                 continue;
1835                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1836
1837                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1838                                                &clp->cl_state))
1839                                 nfs4_state_start_reclaim_nograce(clp);
1840                         else
1841                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1842                                         &clp->cl_state);
1843
1844                         pnfs_destroy_all_layouts(clp);
1845                 }
1846
1847                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1848                         status = nfs4_check_lease(clp);
1849                         if (status < 0)
1850                                 goto out_error;
1851                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1852                                 continue;
1853                 }
1854
1855                 /* Initialize or reset the session */
1856                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1857                    && nfs4_has_session(clp)) {
1858                         status = nfs4_reset_session(clp);
1859                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1860                                 continue;
1861                         if (status < 0)
1862                                 goto out_error;
1863                 }
1864
1865                 /* Send BIND_CONN_TO_SESSION */
1866                 if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
1867                                 &clp->cl_state) && nfs4_has_session(clp)) {
1868                         status = nfs4_bind_conn_to_session(clp);
1869                         if (status < 0)
1870                                 goto out_error;
1871                         continue;
1872                 }
1873
1874                 /* First recover reboot state... */
1875                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1876                         status = nfs4_do_reclaim(clp,
1877                                 clp->cl_mvops->reboot_recovery_ops);
1878                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1879                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1880                                 continue;
1881                         nfs4_state_end_reclaim_reboot(clp);
1882                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1883                                 continue;
1884                         if (status < 0)
1885                                 goto out_error;
1886                 }
1887
1888                 /* Now recover expired state... */
1889                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1890                         status = nfs4_do_reclaim(clp,
1891                                 clp->cl_mvops->nograce_recovery_ops);
1892                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1893                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1894                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1895                                 continue;
1896                         if (status < 0)
1897                                 goto out_error;
1898                 }
1899
1900                 nfs4_end_drain_session(clp);
1901                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1902                         nfs_client_return_marked_delegations(clp);
1903                         continue;
1904                 }
1905                 /* Recall session slots */
1906                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1907                    && nfs4_has_session(clp)) {
1908                         status = nfs4_recall_slot(clp);
1909                         if (status < 0)
1910                                 goto out_error;
1911                         continue;
1912                 }
1913
1914
1915                 nfs4_clear_state_manager_bit(clp);
1916                 /* Did we race with an attempt to give us more work? */
1917                 if (clp->cl_state == 0)
1918                         break;
1919                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1920                         break;
1921         } while (atomic_read(&clp->cl_count) > 1);
1922         return;
1923 out_error:
1924         pr_warn_ratelimited("NFS: state manager failed on NFSv4 server %s"
1925                         " with error %d\n", clp->cl_hostname, -status);
1926         nfs4_end_drain_session(clp);
1927         nfs4_clear_state_manager_bit(clp);
1928 }
1929
1930 static int nfs4_run_state_manager(void *ptr)
1931 {
1932         struct nfs_client *clp = ptr;
1933
1934         allow_signal(SIGKILL);
1935         nfs4_state_manager(clp);
1936         nfs_put_client(clp);
1937         module_put_and_exit(0);
1938         return 0;
1939 }
1940
1941 /*
1942  * Local variables:
1943  *  c-basic-offset: 8
1944  * End:
1945  */