NFSv4: The state manager shouldn't exit on errors that were handled
[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/smp_lock.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/workqueue.h>
50 #include <linux/bitops.h>
51
52 #include "nfs4_fs.h"
53 #include "callback.h"
54 #include "delegation.h"
55 #include "internal.h"
56
57 #define OPENOWNER_POOL_SIZE     8
58
59 const nfs4_stateid zero_stateid;
60
61 static LIST_HEAD(nfs4_clientid_list);
62
63 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
64 {
65         unsigned short port;
66         int status;
67
68         port = nfs_callback_tcpport;
69         if (clp->cl_addr.ss_family == AF_INET6)
70                 port = nfs_callback_tcpport6;
71
72         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred);
73         if (status == 0)
74                 status = nfs4_proc_setclientid_confirm(clp, cred);
75         if (status == 0)
76                 nfs4_schedule_state_renewal(clp);
77         return status;
78 }
79
80 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
81 {
82         struct rpc_cred *cred = NULL;
83
84         if (clp->cl_machine_cred != NULL)
85                 cred = get_rpccred(clp->cl_machine_cred);
86         return cred;
87 }
88
89 static void nfs4_clear_machine_cred(struct nfs_client *clp)
90 {
91         struct rpc_cred *cred;
92
93         spin_lock(&clp->cl_lock);
94         cred = clp->cl_machine_cred;
95         clp->cl_machine_cred = NULL;
96         spin_unlock(&clp->cl_lock);
97         if (cred != NULL)
98                 put_rpccred(cred);
99 }
100
101 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
102 {
103         struct nfs4_state_owner *sp;
104         struct rb_node *pos;
105         struct rpc_cred *cred = NULL;
106
107         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
108                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
109                 if (list_empty(&sp->so_states))
110                         continue;
111                 cred = get_rpccred(sp->so_cred);
112                 break;
113         }
114         return cred;
115 }
116
117 #if defined(CONFIG_NFS_V4_1)
118
119 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
120 {
121         struct rpc_cred *cred;
122
123         spin_lock(&clp->cl_lock);
124         cred = nfs4_get_machine_cred_locked(clp);
125         spin_unlock(&clp->cl_lock);
126         return cred;
127 }
128
129 #endif /* CONFIG_NFS_V4_1 */
130
131 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
132 {
133         struct nfs4_state_owner *sp;
134         struct rb_node *pos;
135         struct rpc_cred *cred;
136
137         spin_lock(&clp->cl_lock);
138         cred = nfs4_get_machine_cred_locked(clp);
139         if (cred != NULL)
140                 goto out;
141         pos = rb_first(&clp->cl_state_owners);
142         if (pos != NULL) {
143                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
144                 cred = get_rpccred(sp->so_cred);
145         }
146 out:
147         spin_unlock(&clp->cl_lock);
148         return cred;
149 }
150
151 static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
152                 __u64 minval, int maxbits)
153 {
154         struct rb_node **p, *parent;
155         struct nfs_unique_id *pos;
156         __u64 mask = ~0ULL;
157
158         if (maxbits < 64)
159                 mask = (1ULL << maxbits) - 1ULL;
160
161         /* Ensure distribution is more or less flat */
162         get_random_bytes(&new->id, sizeof(new->id));
163         new->id &= mask;
164         if (new->id < minval)
165                 new->id += minval;
166 retry:
167         p = &root->rb_node;
168         parent = NULL;
169
170         while (*p != NULL) {
171                 parent = *p;
172                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
173
174                 if (new->id < pos->id)
175                         p = &(*p)->rb_left;
176                 else if (new->id > pos->id)
177                         p = &(*p)->rb_right;
178                 else
179                         goto id_exists;
180         }
181         rb_link_node(&new->rb_node, parent, p);
182         rb_insert_color(&new->rb_node, root);
183         return;
184 id_exists:
185         for (;;) {
186                 new->id++;
187                 if (new->id < minval || (new->id & mask) != new->id) {
188                         new->id = minval;
189                         break;
190                 }
191                 parent = rb_next(parent);
192                 if (parent == NULL)
193                         break;
194                 pos = rb_entry(parent, struct nfs_unique_id, rb_node);
195                 if (new->id < pos->id)
196                         break;
197         }
198         goto retry;
199 }
200
201 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
202 {
203         rb_erase(&id->rb_node, root);
204 }
205
206 static struct nfs4_state_owner *
207 nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
208 {
209         struct nfs_client *clp = server->nfs_client;
210         struct rb_node **p = &clp->cl_state_owners.rb_node,
211                        *parent = NULL;
212         struct nfs4_state_owner *sp, *res = NULL;
213
214         while (*p != NULL) {
215                 parent = *p;
216                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
217
218                 if (server < sp->so_server) {
219                         p = &parent->rb_left;
220                         continue;
221                 }
222                 if (server > sp->so_server) {
223                         p = &parent->rb_right;
224                         continue;
225                 }
226                 if (cred < sp->so_cred)
227                         p = &parent->rb_left;
228                 else if (cred > sp->so_cred)
229                         p = &parent->rb_right;
230                 else {
231                         atomic_inc(&sp->so_count);
232                         res = sp;
233                         break;
234                 }
235         }
236         return res;
237 }
238
239 static struct nfs4_state_owner *
240 nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
241 {
242         struct rb_node **p = &clp->cl_state_owners.rb_node,
243                        *parent = NULL;
244         struct nfs4_state_owner *sp;
245
246         while (*p != NULL) {
247                 parent = *p;
248                 sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
249
250                 if (new->so_server < sp->so_server) {
251                         p = &parent->rb_left;
252                         continue;
253                 }
254                 if (new->so_server > sp->so_server) {
255                         p = &parent->rb_right;
256                         continue;
257                 }
258                 if (new->so_cred < sp->so_cred)
259                         p = &parent->rb_left;
260                 else if (new->so_cred > sp->so_cred)
261                         p = &parent->rb_right;
262                 else {
263                         atomic_inc(&sp->so_count);
264                         return sp;
265                 }
266         }
267         nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
268         rb_link_node(&new->so_client_node, parent, p);
269         rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
270         return new;
271 }
272
273 static void
274 nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
275 {
276         if (!RB_EMPTY_NODE(&sp->so_client_node))
277                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
278         nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
279 }
280
281 /*
282  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
283  * create a new state_owner.
284  *
285  */
286 static struct nfs4_state_owner *
287 nfs4_alloc_state_owner(void)
288 {
289         struct nfs4_state_owner *sp;
290
291         sp = kzalloc(sizeof(*sp),GFP_KERNEL);
292         if (!sp)
293                 return NULL;
294         spin_lock_init(&sp->so_lock);
295         INIT_LIST_HEAD(&sp->so_states);
296         INIT_LIST_HEAD(&sp->so_delegations);
297         rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
298         sp->so_seqid.sequence = &sp->so_sequence;
299         spin_lock_init(&sp->so_sequence.lock);
300         INIT_LIST_HEAD(&sp->so_sequence.list);
301         atomic_set(&sp->so_count, 1);
302         return sp;
303 }
304
305 static void
306 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
307 {
308         if (!RB_EMPTY_NODE(&sp->so_client_node)) {
309                 struct nfs_client *clp = sp->so_client;
310
311                 spin_lock(&clp->cl_lock);
312                 rb_erase(&sp->so_client_node, &clp->cl_state_owners);
313                 RB_CLEAR_NODE(&sp->so_client_node);
314                 spin_unlock(&clp->cl_lock);
315         }
316 }
317
318 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
319 {
320         struct nfs_client *clp = server->nfs_client;
321         struct nfs4_state_owner *sp, *new;
322
323         spin_lock(&clp->cl_lock);
324         sp = nfs4_find_state_owner(server, cred);
325         spin_unlock(&clp->cl_lock);
326         if (sp != NULL)
327                 return sp;
328         new = nfs4_alloc_state_owner();
329         if (new == NULL)
330                 return NULL;
331         new->so_client = clp;
332         new->so_server = server;
333         new->so_cred = cred;
334         spin_lock(&clp->cl_lock);
335         sp = nfs4_insert_state_owner(clp, new);
336         spin_unlock(&clp->cl_lock);
337         if (sp == new)
338                 get_rpccred(cred);
339         else {
340                 rpc_destroy_wait_queue(&new->so_sequence.wait);
341                 kfree(new);
342         }
343         return sp;
344 }
345
346 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
347 {
348         struct nfs_client *clp = sp->so_client;
349         struct rpc_cred *cred = sp->so_cred;
350
351         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
352                 return;
353         nfs4_remove_state_owner(clp, sp);
354         spin_unlock(&clp->cl_lock);
355         rpc_destroy_wait_queue(&sp->so_sequence.wait);
356         put_rpccred(cred);
357         kfree(sp);
358 }
359
360 static struct nfs4_state *
361 nfs4_alloc_open_state(void)
362 {
363         struct nfs4_state *state;
364
365         state = kzalloc(sizeof(*state), GFP_KERNEL);
366         if (!state)
367                 return NULL;
368         atomic_set(&state->count, 1);
369         INIT_LIST_HEAD(&state->lock_states);
370         spin_lock_init(&state->state_lock);
371         seqlock_init(&state->seqlock);
372         return state;
373 }
374
375 void
376 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
377 {
378         if (state->state == fmode)
379                 return;
380         /* NB! List reordering - see the reclaim code for why.  */
381         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
382                 if (fmode & FMODE_WRITE)
383                         list_move(&state->open_states, &state->owner->so_states);
384                 else
385                         list_move_tail(&state->open_states, &state->owner->so_states);
386         }
387         state->state = fmode;
388 }
389
390 static struct nfs4_state *
391 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
392 {
393         struct nfs_inode *nfsi = NFS_I(inode);
394         struct nfs4_state *state;
395
396         list_for_each_entry(state, &nfsi->open_states, inode_states) {
397                 if (state->owner != owner)
398                         continue;
399                 if (atomic_inc_not_zero(&state->count))
400                         return state;
401         }
402         return NULL;
403 }
404
405 static void
406 nfs4_free_open_state(struct nfs4_state *state)
407 {
408         kfree(state);
409 }
410
411 struct nfs4_state *
412 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
413 {
414         struct nfs4_state *state, *new;
415         struct nfs_inode *nfsi = NFS_I(inode);
416
417         spin_lock(&inode->i_lock);
418         state = __nfs4_find_state_byowner(inode, owner);
419         spin_unlock(&inode->i_lock);
420         if (state)
421                 goto out;
422         new = nfs4_alloc_open_state();
423         spin_lock(&owner->so_lock);
424         spin_lock(&inode->i_lock);
425         state = __nfs4_find_state_byowner(inode, owner);
426         if (state == NULL && new != NULL) {
427                 state = new;
428                 state->owner = owner;
429                 atomic_inc(&owner->so_count);
430                 list_add(&state->inode_states, &nfsi->open_states);
431                 state->inode = igrab(inode);
432                 spin_unlock(&inode->i_lock);
433                 /* Note: The reclaim code dictates that we add stateless
434                  * and read-only stateids to the end of the list */
435                 list_add_tail(&state->open_states, &owner->so_states);
436                 spin_unlock(&owner->so_lock);
437         } else {
438                 spin_unlock(&inode->i_lock);
439                 spin_unlock(&owner->so_lock);
440                 if (new)
441                         nfs4_free_open_state(new);
442         }
443 out:
444         return state;
445 }
446
447 void nfs4_put_open_state(struct nfs4_state *state)
448 {
449         struct inode *inode = state->inode;
450         struct nfs4_state_owner *owner = state->owner;
451
452         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
453                 return;
454         spin_lock(&inode->i_lock);
455         list_del(&state->inode_states);
456         list_del(&state->open_states);
457         spin_unlock(&inode->i_lock);
458         spin_unlock(&owner->so_lock);
459         iput(inode);
460         nfs4_free_open_state(state);
461         nfs4_put_state_owner(owner);
462 }
463
464 /*
465  * Close the current file.
466  */
467 static void __nfs4_close(struct path *path, struct nfs4_state *state, fmode_t fmode, int wait)
468 {
469         struct nfs4_state_owner *owner = state->owner;
470         int call_close = 0;
471         fmode_t newstate;
472
473         atomic_inc(&owner->so_count);
474         /* Protect against nfs4_find_state() */
475         spin_lock(&owner->so_lock);
476         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
477                 case FMODE_READ:
478                         state->n_rdonly--;
479                         break;
480                 case FMODE_WRITE:
481                         state->n_wronly--;
482                         break;
483                 case FMODE_READ|FMODE_WRITE:
484                         state->n_rdwr--;
485         }
486         newstate = FMODE_READ|FMODE_WRITE;
487         if (state->n_rdwr == 0) {
488                 if (state->n_rdonly == 0) {
489                         newstate &= ~FMODE_READ;
490                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
491                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
492                 }
493                 if (state->n_wronly == 0) {
494                         newstate &= ~FMODE_WRITE;
495                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
496                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
497                 }
498                 if (newstate == 0)
499                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
500         }
501         nfs4_state_set_mode_locked(state, newstate);
502         spin_unlock(&owner->so_lock);
503
504         if (!call_close) {
505                 nfs4_put_open_state(state);
506                 nfs4_put_state_owner(owner);
507         } else
508                 nfs4_do_close(path, state, wait);
509 }
510
511 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
512 {
513         __nfs4_close(path, state, fmode, 0);
514 }
515
516 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
517 {
518         __nfs4_close(path, state, fmode, 1);
519 }
520
521 /*
522  * Search the state->lock_states for an existing lock_owner
523  * that is compatible with current->files
524  */
525 static struct nfs4_lock_state *
526 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
527 {
528         struct nfs4_lock_state *pos;
529         list_for_each_entry(pos, &state->lock_states, ls_locks) {
530                 if (pos->ls_owner != fl_owner)
531                         continue;
532                 atomic_inc(&pos->ls_count);
533                 return pos;
534         }
535         return NULL;
536 }
537
538 /*
539  * Return a compatible lock_state. If no initialized lock_state structure
540  * exists, return an uninitialized one.
541  *
542  */
543 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
544 {
545         struct nfs4_lock_state *lsp;
546         struct nfs_client *clp = state->owner->so_client;
547
548         lsp = kzalloc(sizeof(*lsp), GFP_KERNEL);
549         if (lsp == NULL)
550                 return NULL;
551         rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
552         spin_lock_init(&lsp->ls_sequence.lock);
553         INIT_LIST_HEAD(&lsp->ls_sequence.list);
554         lsp->ls_seqid.sequence = &lsp->ls_sequence;
555         atomic_set(&lsp->ls_count, 1);
556         lsp->ls_state = state;
557         lsp->ls_owner = fl_owner;
558         spin_lock(&clp->cl_lock);
559         nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
560         spin_unlock(&clp->cl_lock);
561         INIT_LIST_HEAD(&lsp->ls_locks);
562         return lsp;
563 }
564
565 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
566 {
567         struct nfs_client *clp = lsp->ls_state->owner->so_client;
568
569         spin_lock(&clp->cl_lock);
570         nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
571         spin_unlock(&clp->cl_lock);
572         rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
573         kfree(lsp);
574 }
575
576 /*
577  * Return a compatible lock_state. If no initialized lock_state structure
578  * exists, return an uninitialized one.
579  *
580  */
581 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
582 {
583         struct nfs4_lock_state *lsp, *new = NULL;
584         
585         for(;;) {
586                 spin_lock(&state->state_lock);
587                 lsp = __nfs4_find_lock_state(state, owner);
588                 if (lsp != NULL)
589                         break;
590                 if (new != NULL) {
591                         list_add(&new->ls_locks, &state->lock_states);
592                         set_bit(LK_STATE_IN_USE, &state->flags);
593                         lsp = new;
594                         new = NULL;
595                         break;
596                 }
597                 spin_unlock(&state->state_lock);
598                 new = nfs4_alloc_lock_state(state, owner);
599                 if (new == NULL)
600                         return NULL;
601         }
602         spin_unlock(&state->state_lock);
603         if (new != NULL)
604                 nfs4_free_lock_state(new);
605         return lsp;
606 }
607
608 /*
609  * Release reference to lock_state, and free it if we see that
610  * it is no longer in use
611  */
612 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
613 {
614         struct nfs4_state *state;
615
616         if (lsp == NULL)
617                 return;
618         state = lsp->ls_state;
619         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
620                 return;
621         list_del(&lsp->ls_locks);
622         if (list_empty(&state->lock_states))
623                 clear_bit(LK_STATE_IN_USE, &state->flags);
624         spin_unlock(&state->state_lock);
625         nfs4_free_lock_state(lsp);
626 }
627
628 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
629 {
630         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
631
632         dst->fl_u.nfs4_fl.owner = lsp;
633         atomic_inc(&lsp->ls_count);
634 }
635
636 static void nfs4_fl_release_lock(struct file_lock *fl)
637 {
638         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
639 }
640
641 static const struct file_lock_operations nfs4_fl_lock_ops = {
642         .fl_copy_lock = nfs4_fl_copy_lock,
643         .fl_release_private = nfs4_fl_release_lock,
644 };
645
646 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
647 {
648         struct nfs4_lock_state *lsp;
649
650         if (fl->fl_ops != NULL)
651                 return 0;
652         lsp = nfs4_get_lock_state(state, fl->fl_owner);
653         if (lsp == NULL)
654                 return -ENOMEM;
655         fl->fl_u.nfs4_fl.owner = lsp;
656         fl->fl_ops = &nfs4_fl_lock_ops;
657         return 0;
658 }
659
660 /*
661  * Byte-range lock aware utility to initialize the stateid of read/write
662  * requests.
663  */
664 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
665 {
666         struct nfs4_lock_state *lsp;
667         int seq;
668
669         do {
670                 seq = read_seqbegin(&state->seqlock);
671                 memcpy(dst, &state->stateid, sizeof(*dst));
672         } while (read_seqretry(&state->seqlock, seq));
673         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
674                 return;
675
676         spin_lock(&state->state_lock);
677         lsp = __nfs4_find_lock_state(state, fl_owner);
678         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
679                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
680         spin_unlock(&state->state_lock);
681         nfs4_put_lock_state(lsp);
682 }
683
684 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
685 {
686         struct nfs_seqid *new;
687
688         new = kmalloc(sizeof(*new), GFP_KERNEL);
689         if (new != NULL) {
690                 new->sequence = counter;
691                 INIT_LIST_HEAD(&new->list);
692         }
693         return new;
694 }
695
696 void nfs_free_seqid(struct nfs_seqid *seqid)
697 {
698         if (!list_empty(&seqid->list)) {
699                 struct rpc_sequence *sequence = seqid->sequence->sequence;
700
701                 spin_lock(&sequence->lock);
702                 list_del(&seqid->list);
703                 spin_unlock(&sequence->lock);
704                 rpc_wake_up(&sequence->wait);
705         }
706         kfree(seqid);
707 }
708
709 /*
710  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
711  * failed with a seqid incrementing error -
712  * see comments nfs_fs.h:seqid_mutating_error()
713  */
714 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
715 {
716         BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
717         switch (status) {
718                 case 0:
719                         break;
720                 case -NFS4ERR_BAD_SEQID:
721                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
722                                 return;
723                         printk(KERN_WARNING "NFS: v4 server returned a bad"
724                                         " sequence-id error on an"
725                                         " unconfirmed sequence %p!\n",
726                                         seqid->sequence);
727                 case -NFS4ERR_STALE_CLIENTID:
728                 case -NFS4ERR_STALE_STATEID:
729                 case -NFS4ERR_BAD_STATEID:
730                 case -NFS4ERR_BADXDR:
731                 case -NFS4ERR_RESOURCE:
732                 case -NFS4ERR_NOFILEHANDLE:
733                         /* Non-seqid mutating errors */
734                         return;
735         };
736         /*
737          * Note: no locking needed as we are guaranteed to be first
738          * on the sequence list
739          */
740         seqid->sequence->counter++;
741 }
742
743 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
744 {
745         struct nfs4_state_owner *sp = container_of(seqid->sequence,
746                                         struct nfs4_state_owner, so_seqid);
747         struct nfs_server *server = sp->so_server;
748
749         if (status == -NFS4ERR_BAD_SEQID)
750                 nfs4_drop_state_owner(sp);
751         if (!nfs4_has_session(server->nfs_client))
752                 nfs_increment_seqid(status, seqid);
753 }
754
755 /*
756  * Increment the seqid if the LOCK/LOCKU succeeded, or
757  * failed with a seqid incrementing error -
758  * see comments nfs_fs.h:seqid_mutating_error()
759  */
760 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
761 {
762         nfs_increment_seqid(status, seqid);
763 }
764
765 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
766 {
767         struct rpc_sequence *sequence = seqid->sequence->sequence;
768         int status = 0;
769
770         spin_lock(&sequence->lock);
771         if (list_empty(&seqid->list))
772                 list_add_tail(&seqid->list, &sequence->list);
773         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
774                 goto unlock;
775         rpc_sleep_on(&sequence->wait, task, NULL);
776         status = -EAGAIN;
777 unlock:
778         spin_unlock(&sequence->lock);
779         return status;
780 }
781
782 static int nfs4_run_state_manager(void *);
783
784 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
785 {
786         smp_mb__before_clear_bit();
787         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
788         smp_mb__after_clear_bit();
789         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
790         rpc_wake_up(&clp->cl_rpcwaitq);
791 }
792
793 /*
794  * Schedule the nfs_client asynchronous state management routine
795  */
796 void nfs4_schedule_state_manager(struct nfs_client *clp)
797 {
798         struct task_struct *task;
799
800         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
801                 return;
802         __module_get(THIS_MODULE);
803         atomic_inc(&clp->cl_count);
804         task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
805                                 rpc_peeraddr2str(clp->cl_rpcclient,
806                                                         RPC_DISPLAY_ADDR));
807         if (!IS_ERR(task))
808                 return;
809         nfs4_clear_state_manager_bit(clp);
810         nfs_put_client(clp);
811         module_put(THIS_MODULE);
812 }
813
814 /*
815  * Schedule a state recovery attempt
816  */
817 void nfs4_schedule_state_recovery(struct nfs_client *clp)
818 {
819         if (!clp)
820                 return;
821         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
822                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
823         nfs4_schedule_state_manager(clp);
824 }
825
826 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
827 {
828
829         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
830         /* Don't recover state that expired before the reboot */
831         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
832                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
833                 return 0;
834         }
835         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
836         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
837         return 1;
838 }
839
840 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
841 {
842         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
843         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
844         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
845         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
846         return 1;
847 }
848
849 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
850 {
851         struct inode *inode = state->inode;
852         struct nfs_inode *nfsi = NFS_I(inode);
853         struct file_lock *fl;
854         int status = 0;
855
856         if (inode->i_flock == NULL)
857                 return 0;
858
859         /* Guard against delegation returns and new lock/unlock calls */
860         down_write(&nfsi->rwsem);
861         /* Protect inode->i_flock using the BKL */
862         lock_kernel();
863         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
864                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
865                         continue;
866                 if (nfs_file_open_context(fl->fl_file)->state != state)
867                         continue;
868                 unlock_kernel();
869                 status = ops->recover_lock(state, fl);
870                 switch (status) {
871                         case 0:
872                                 break;
873                         case -ESTALE:
874                         case -NFS4ERR_ADMIN_REVOKED:
875                         case -NFS4ERR_STALE_STATEID:
876                         case -NFS4ERR_BAD_STATEID:
877                         case -NFS4ERR_EXPIRED:
878                         case -NFS4ERR_NO_GRACE:
879                         case -NFS4ERR_STALE_CLIENTID:
880                                 goto out;
881                         default:
882                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
883                                                 __func__, status);
884                         case -ENOMEM:
885                         case -NFS4ERR_DENIED:
886                         case -NFS4ERR_RECLAIM_BAD:
887                         case -NFS4ERR_RECLAIM_CONFLICT:
888                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
889                                 status = 0;
890                 }
891                 lock_kernel();
892         }
893         unlock_kernel();
894 out:
895         up_write(&nfsi->rwsem);
896         return status;
897 }
898
899 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
900 {
901         struct nfs4_state *state;
902         struct nfs4_lock_state *lock;
903         int status = 0;
904
905         /* Note: we rely on the sp->so_states list being ordered 
906          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
907          * states first.
908          * This is needed to ensure that the server won't give us any
909          * read delegations that we have to return if, say, we are
910          * recovering after a network partition or a reboot from a
911          * server that doesn't support a grace period.
912          */
913 restart:
914         spin_lock(&sp->so_lock);
915         list_for_each_entry(state, &sp->so_states, open_states) {
916                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
917                         continue;
918                 if (state->state == 0)
919                         continue;
920                 atomic_inc(&state->count);
921                 spin_unlock(&sp->so_lock);
922                 status = ops->recover_open(sp, state);
923                 if (status >= 0) {
924                         status = nfs4_reclaim_locks(state, ops);
925                         if (status >= 0) {
926                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
927                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
928                                                 printk("%s: Lock reclaim failed!\n",
929                                                         __func__);
930                                 }
931                                 nfs4_put_open_state(state);
932                                 goto restart;
933                         }
934                 }
935                 switch (status) {
936                         default:
937                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
938                                                 __func__, status);
939                         case -ENOENT:
940                         case -ENOMEM:
941                         case -ESTALE:
942                                 /*
943                                  * Open state on this file cannot be recovered
944                                  * All we can do is revert to using the zero stateid.
945                                  */
946                                 memset(state->stateid.data, 0,
947                                         sizeof(state->stateid.data));
948                                 /* Mark the file as being 'closed' */
949                                 state->state = 0;
950                                 break;
951                         case -NFS4ERR_ADMIN_REVOKED:
952                         case -NFS4ERR_STALE_STATEID:
953                         case -NFS4ERR_BAD_STATEID:
954                         case -NFS4ERR_RECLAIM_BAD:
955                         case -NFS4ERR_RECLAIM_CONFLICT:
956                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
957                                 break;
958                         case -NFS4ERR_EXPIRED:
959                         case -NFS4ERR_NO_GRACE:
960                                 nfs4_state_mark_reclaim_nograce(sp->so_client, state);
961                         case -NFS4ERR_STALE_CLIENTID:
962                                 goto out_err;
963                 }
964                 nfs4_put_open_state(state);
965                 goto restart;
966         }
967         spin_unlock(&sp->so_lock);
968         return 0;
969 out_err:
970         nfs4_put_open_state(state);
971         return status;
972 }
973
974 static void nfs4_clear_open_state(struct nfs4_state *state)
975 {
976         struct nfs4_lock_state *lock;
977
978         clear_bit(NFS_DELEGATED_STATE, &state->flags);
979         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
980         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
981         clear_bit(NFS_O_RDWR_STATE, &state->flags);
982         list_for_each_entry(lock, &state->lock_states, ls_locks) {
983                 lock->ls_seqid.flags = 0;
984                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
985         }
986 }
987
988 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
989 {
990         struct nfs4_state_owner *sp;
991         struct rb_node *pos;
992         struct nfs4_state *state;
993
994         /* Reset all sequence ids to zero */
995         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
996                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
997                 sp->so_seqid.flags = 0;
998                 spin_lock(&sp->so_lock);
999                 list_for_each_entry(state, &sp->so_states, open_states) {
1000                         if (mark_reclaim(clp, state))
1001                                 nfs4_clear_open_state(state);
1002                 }
1003                 spin_unlock(&sp->so_lock);
1004         }
1005 }
1006
1007 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1008 {
1009         /* Mark all delegations for reclaim */
1010         nfs_delegation_mark_reclaim(clp);
1011         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1012 }
1013
1014 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1015 {
1016         struct nfs4_state_owner *sp;
1017         struct rb_node *pos;
1018         struct nfs4_state *state;
1019
1020         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1021                 return;
1022
1023         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1024                 sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1025                 spin_lock(&sp->so_lock);
1026                 list_for_each_entry(state, &sp->so_states, open_states) {
1027                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
1028                                 continue;
1029                         nfs4_state_mark_reclaim_nograce(clp, state);
1030                 }
1031                 spin_unlock(&sp->so_lock);
1032         }
1033
1034         nfs_delegation_reap_unclaimed(clp);
1035 }
1036
1037 static void nfs_delegation_clear_all(struct nfs_client *clp)
1038 {
1039         nfs_delegation_mark_reclaim(clp);
1040         nfs_delegation_reap_unclaimed(clp);
1041 }
1042
1043 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1044 {
1045         nfs_delegation_clear_all(clp);
1046         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1047 }
1048
1049 static void nfs4_state_end_reclaim_nograce(struct nfs_client *clp)
1050 {
1051         clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1052 }
1053
1054 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1055 {
1056         switch (error) {
1057                 case -NFS4ERR_CB_PATH_DOWN:
1058                         nfs_handle_cb_pathdown(clp);
1059                         return 0;
1060                 case -NFS4ERR_STALE_CLIENTID:
1061                 case -NFS4ERR_LEASE_MOVED:
1062                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1063                         nfs4_state_end_reclaim_reboot(clp);
1064                         nfs4_state_start_reclaim_reboot(clp);
1065                         break;
1066                 case -NFS4ERR_EXPIRED:
1067                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1068                         nfs4_state_start_reclaim_nograce(clp);
1069                 case -NFS4ERR_BADSESSION:
1070                 case -NFS4ERR_BADSLOT:
1071                 case -NFS4ERR_BAD_HIGH_SLOT:
1072                 case -NFS4ERR_DEADSESSION:
1073                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1074                 case -NFS4ERR_SEQ_FALSE_RETRY:
1075                 case -NFS4ERR_SEQ_MISORDERED:
1076                         set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1077         }
1078         return error;
1079 }
1080
1081 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1082 {
1083         struct rb_node *pos;
1084         int status = 0;
1085
1086 restart:
1087         spin_lock(&clp->cl_lock);
1088         for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1089                 struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1090                 if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
1091                         continue;
1092                 atomic_inc(&sp->so_count);
1093                 spin_unlock(&clp->cl_lock);
1094                 status = nfs4_reclaim_open_state(sp, ops);
1095                 if (status < 0) {
1096                         set_bit(ops->owner_flag_bit, &sp->so_flags);
1097                         nfs4_put_state_owner(sp);
1098                         return nfs4_recovery_handle_error(clp, status);
1099                 }
1100                 nfs4_put_state_owner(sp);
1101                 goto restart;
1102         }
1103         spin_unlock(&clp->cl_lock);
1104         return status;
1105 }
1106
1107 static int nfs4_check_lease(struct nfs_client *clp)
1108 {
1109         struct rpc_cred *cred;
1110         struct nfs4_state_maintenance_ops *ops =
1111                 nfs4_state_renewal_ops[clp->cl_minorversion];
1112         int status = -NFS4ERR_EXPIRED;
1113
1114         /* Is the client already known to have an expired lease? */
1115         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1116                 return 0;
1117         spin_lock(&clp->cl_lock);
1118         cred = ops->get_state_renewal_cred_locked(clp);
1119         spin_unlock(&clp->cl_lock);
1120         if (cred == NULL) {
1121                 cred = nfs4_get_setclientid_cred(clp);
1122                 if (cred == NULL)
1123                         goto out;
1124         }
1125         status = ops->renew_lease(clp, cred);
1126         put_rpccred(cred);
1127 out:
1128         return nfs4_recovery_handle_error(clp, status);
1129 }
1130
1131 static int nfs4_reclaim_lease(struct nfs_client *clp)
1132 {
1133         struct rpc_cred *cred;
1134         struct nfs4_state_recovery_ops *ops =
1135                 nfs4_reboot_recovery_ops[clp->cl_minorversion];
1136         int status = -ENOENT;
1137
1138         cred = ops->get_clid_cred(clp);
1139         if (cred != NULL) {
1140                 status = ops->establish_clid(clp, cred);
1141                 put_rpccred(cred);
1142                 /* Handle case where the user hasn't set up machine creds */
1143                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1144                         nfs4_clear_machine_cred(clp);
1145                         status = -EAGAIN;
1146                 }
1147                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1148                         status = -EPROTONOSUPPORT;
1149         }
1150         return status;
1151 }
1152
1153 #ifdef CONFIG_NFS_V4_1
1154 static void nfs4_session_recovery_handle_error(struct nfs_client *clp, int err)
1155 {
1156         switch (err) {
1157         case -NFS4ERR_STALE_CLIENTID:
1158                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1159                 set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1160         }
1161 }
1162
1163 static int nfs4_reset_session(struct nfs_client *clp)
1164 {
1165         int status;
1166
1167         status = nfs4_proc_destroy_session(clp->cl_session);
1168         if (status && status != -NFS4ERR_BADSESSION &&
1169             status != -NFS4ERR_DEADSESSION) {
1170                 nfs4_session_recovery_handle_error(clp, status);
1171                 goto out;
1172         }
1173
1174         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1175         status = nfs4_proc_create_session(clp, 1);
1176         if (status)
1177                 nfs4_session_recovery_handle_error(clp, status);
1178                 /* fall through*/
1179 out:
1180         /* Wake up the next rpc task even on error */
1181         rpc_wake_up_next(&clp->cl_session->fc_slot_table.slot_tbl_waitq);
1182         return status;
1183 }
1184
1185 static int nfs4_initialize_session(struct nfs_client *clp)
1186 {
1187         int status;
1188
1189         status = nfs4_proc_create_session(clp, 0);
1190         if (!status) {
1191                 nfs_mark_client_ready(clp, NFS_CS_READY);
1192         } else if (status == -NFS4ERR_STALE_CLIENTID) {
1193                 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1194                 set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1195         } else {
1196                 nfs_mark_client_ready(clp, status);
1197         }
1198         return status;
1199 }
1200 #else /* CONFIG_NFS_V4_1 */
1201 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1202 static int nfs4_initialize_session(struct nfs_client *clp) { return 0; }
1203 #endif /* CONFIG_NFS_V4_1 */
1204
1205 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1206  * on EXCHANGE_ID for v4.1
1207  */
1208 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1209 {
1210         if (nfs4_has_session(clp)) {
1211                 switch (status) {
1212                 case -NFS4ERR_DELAY:
1213                 case -NFS4ERR_CLID_INUSE:
1214                 case -EAGAIN:
1215                         break;
1216
1217                 case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1218                                          * in nfs4_exchange_id */
1219                 default:
1220                         return;
1221                 }
1222         }
1223         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1224 }
1225
1226 static void nfs4_state_manager(struct nfs_client *clp)
1227 {
1228         int status = 0;
1229
1230         /* Ensure exclusive access to NFSv4 state */
1231         for(;;) {
1232                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1233                         /* We're going to have to re-establish a clientid */
1234                         status = nfs4_reclaim_lease(clp);
1235                         if (status) {
1236                                 nfs4_set_lease_expired(clp, status);
1237                                 if (status == -EAGAIN)
1238                                         continue;
1239                                 if (clp->cl_cons_state ==
1240                                                         NFS_CS_SESSION_INITING)
1241                                         nfs_mark_client_ready(clp, status);
1242                                 goto out_error;
1243                         }
1244                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1245                 }
1246
1247                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1248                         status = nfs4_check_lease(clp);
1249                         if (status != 0)
1250                                 continue;
1251                 }
1252                 /* Initialize or reset the session */
1253                 if (test_and_clear_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state)
1254                    && nfs4_has_session(clp)) {
1255                         if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1256                                 status = nfs4_initialize_session(clp);
1257                         else
1258                                 status = nfs4_reset_session(clp);
1259                         if (status) {
1260                                 if (status == -NFS4ERR_STALE_CLIENTID)
1261                                         continue;
1262                                 goto out_error;
1263                         }
1264                 }
1265                 /* First recover reboot state... */
1266                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1267                         status = nfs4_do_reclaim(clp,
1268                                 nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1269                         if (status == -NFS4ERR_STALE_CLIENTID)
1270                                 continue;
1271                         if (test_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state))
1272                                 continue;
1273                         nfs4_state_end_reclaim_reboot(clp);
1274                         continue;
1275                 }
1276
1277                 /* Now recover expired state... */
1278                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1279                         status = nfs4_do_reclaim(clp,
1280                                 nfs4_nograce_recovery_ops[clp->cl_minorversion]);
1281                         if (status < 0) {
1282                                 set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1283                                 if (status == -NFS4ERR_STALE_CLIENTID)
1284                                         continue;
1285                                 if (status == -NFS4ERR_EXPIRED)
1286                                         continue;
1287                                 if (test_bit(NFS4CLNT_SESSION_SETUP,
1288                                                                 &clp->cl_state))
1289                                         continue;
1290                                 goto out_error;
1291                         } else
1292                                 nfs4_state_end_reclaim_nograce(clp);
1293                         continue;
1294                 }
1295
1296                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1297                         nfs_client_return_marked_delegations(clp);
1298                         continue;
1299                 }
1300
1301                 nfs4_clear_state_manager_bit(clp);
1302                 /* Did we race with an attempt to give us more work? */
1303                 if (clp->cl_state == 0)
1304                         break;
1305                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1306                         break;
1307         }
1308         return;
1309 out_error:
1310         printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1311                         " with error %d\n", clp->cl_hostname, -status);
1312         nfs4_clear_state_manager_bit(clp);
1313 }
1314
1315 static int nfs4_run_state_manager(void *ptr)
1316 {
1317         struct nfs_client *clp = ptr;
1318
1319         allow_signal(SIGKILL);
1320         nfs4_state_manager(clp);
1321         nfs_put_client(clp);
1322         module_put_and_exit(0);
1323         return 0;
1324 }
1325
1326 /*
1327  * Local variables:
1328  *  c-basic-offset: 8
1329  * End:
1330  */