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Merge commit 'nfs-for-3.3-4' into nfs-for-next
[~andy/linux] / fs / nfs / nfs4state.c
1 /*
2  *  fs/nfs/nfs4state.c
3  *
4  *  Client-side XDR for NFSv4.
5  *
6  *  Copyright (c) 2002 The Regents of the University of Michigan.
7  *  All rights reserved.
8  *
9  *  Kendrick Smith <kmsmith@umich.edu>
10  *
11  *  Redistribution and use in source and binary forms, with or without
12  *  modification, are permitted provided that the following conditions
13  *  are met:
14  *
15  *  1. Redistributions of source code must retain the above copyright
16  *     notice, this list of conditions and the following disclaimer.
17  *  2. Redistributions in binary form must reproduce the above copyright
18  *     notice, this list of conditions and the following disclaimer in the
19  *     documentation and/or other materials provided with the distribution.
20  *  3. Neither the name of the University nor the names of its
21  *     contributors may be used to endorse or promote products derived
22  *     from this software without specific prior written permission.
23  *
24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35  *
36  * Implementation of the NFSv4 state model.  For the time being,
37  * this is minimal, but will be made much more complex in a
38  * subsequent patch.
39  */
40
41 #include <linux/kernel.h>
42 #include <linux/slab.h>
43 #include <linux/fs.h>
44 #include <linux/nfs_fs.h>
45 #include <linux/nfs_idmap.h>
46 #include <linux/kthread.h>
47 #include <linux/module.h>
48 #include <linux/random.h>
49 #include <linux/ratelimit.h>
50 #include <linux/workqueue.h>
51 #include <linux/bitops.h>
52 #include <linux/jiffies.h>
53
54 #include "nfs4_fs.h"
55 #include "callback.h"
56 #include "delegation.h"
57 #include "internal.h"
58 #include "pnfs.h"
59
60 #define OPENOWNER_POOL_SIZE     8
61
62 const nfs4_stateid zero_stateid;
63
64 static LIST_HEAD(nfs4_clientid_list);
65
66 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
67 {
68         struct nfs4_setclientid_res clid = {
69                 .clientid = clp->cl_clientid,
70                 .confirm = clp->cl_confirm,
71         };
72         unsigned short port;
73         int status;
74
75         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
76                 goto do_confirm;
77         port = nfs_callback_tcpport;
78         if (clp->cl_addr.ss_family == AF_INET6)
79                 port = nfs_callback_tcpport6;
80
81         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
82         if (status != 0)
83                 goto out;
84         clp->cl_clientid = clid.clientid;
85         clp->cl_confirm = clid.confirm;
86         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
87 do_confirm:
88         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
89         if (status != 0)
90                 goto out;
91         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
92         nfs4_schedule_state_renewal(clp);
93 out:
94         return status;
95 }
96
97 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
98 {
99         struct rpc_cred *cred = NULL;
100
101         if (clp->cl_machine_cred != NULL)
102                 cred = get_rpccred(clp->cl_machine_cred);
103         return cred;
104 }
105
106 static void nfs4_clear_machine_cred(struct nfs_client *clp)
107 {
108         struct rpc_cred *cred;
109
110         spin_lock(&clp->cl_lock);
111         cred = clp->cl_machine_cred;
112         clp->cl_machine_cred = NULL;
113         spin_unlock(&clp->cl_lock);
114         if (cred != NULL)
115                 put_rpccred(cred);
116 }
117
118 static struct rpc_cred *
119 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
120 {
121         struct rpc_cred *cred = NULL;
122         struct nfs4_state_owner *sp;
123         struct rb_node *pos;
124
125         for (pos = rb_first(&server->state_owners);
126              pos != NULL;
127              pos = rb_next(pos)) {
128                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
129                 if (list_empty(&sp->so_states))
130                         continue;
131                 cred = get_rpccred(sp->so_cred);
132                 break;
133         }
134         return cred;
135 }
136
137 /**
138  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
139  * @clp: client state handle
140  *
141  * Returns an rpc_cred with reference count bumped, or NULL.
142  * Caller must hold clp->cl_lock.
143  */
144 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
145 {
146         struct rpc_cred *cred = NULL;
147         struct nfs_server *server;
148
149         rcu_read_lock();
150         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
151                 cred = nfs4_get_renew_cred_server_locked(server);
152                 if (cred != NULL)
153                         break;
154         }
155         rcu_read_unlock();
156         return cred;
157 }
158
159 #if defined(CONFIG_NFS_V4_1)
160
161 static int nfs41_setup_state_renewal(struct nfs_client *clp)
162 {
163         int status;
164         struct nfs_fsinfo fsinfo;
165
166         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
167                 nfs4_schedule_state_renewal(clp);
168                 return 0;
169         }
170
171         status = nfs4_proc_get_lease_time(clp, &fsinfo);
172         if (status == 0) {
173                 /* Update lease time and schedule renewal */
174                 spin_lock(&clp->cl_lock);
175                 clp->cl_lease_time = fsinfo.lease_time * HZ;
176                 clp->cl_last_renewal = jiffies;
177                 spin_unlock(&clp->cl_lock);
178
179                 nfs4_schedule_state_renewal(clp);
180         }
181
182         return status;
183 }
184
185 /*
186  * Back channel returns NFS4ERR_DELAY for new requests when
187  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
188  * is ended.
189  */
190 static void nfs4_end_drain_session(struct nfs_client *clp)
191 {
192         struct nfs4_session *ses = clp->cl_session;
193         struct nfs4_slot_table *tbl;
194         int max_slots;
195
196         if (ses == NULL)
197                 return;
198         tbl = &ses->fc_slot_table;
199         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
200                 spin_lock(&tbl->slot_tbl_lock);
201                 max_slots = tbl->max_slots;
202                 while (max_slots--) {
203                         if (rpc_wake_up_first(&tbl->slot_tbl_waitq,
204                                                 nfs4_set_task_privileged,
205                                                 NULL) == NULL)
206                                 break;
207                 }
208                 spin_unlock(&tbl->slot_tbl_lock);
209         }
210 }
211
212 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
213 {
214         spin_lock(&tbl->slot_tbl_lock);
215         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
216                 INIT_COMPLETION(tbl->complete);
217                 spin_unlock(&tbl->slot_tbl_lock);
218                 return wait_for_completion_interruptible(&tbl->complete);
219         }
220         spin_unlock(&tbl->slot_tbl_lock);
221         return 0;
222 }
223
224 static int nfs4_begin_drain_session(struct nfs_client *clp)
225 {
226         struct nfs4_session *ses = clp->cl_session;
227         int ret = 0;
228
229         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
230         /* back channel */
231         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
232         if (ret)
233                 return ret;
234         /* fore channel */
235         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
236 }
237
238 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
239 {
240         int status;
241
242         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
243                 goto do_confirm;
244         nfs4_begin_drain_session(clp);
245         status = nfs4_proc_exchange_id(clp, cred);
246         if (status != 0)
247                 goto out;
248         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
249 do_confirm:
250         status = nfs4_proc_create_session(clp);
251         if (status != 0)
252                 goto out;
253         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
254         nfs41_setup_state_renewal(clp);
255         nfs_mark_client_ready(clp, NFS_CS_READY);
256 out:
257         return status;
258 }
259
260 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
261 {
262         struct rpc_cred *cred;
263
264         spin_lock(&clp->cl_lock);
265         cred = nfs4_get_machine_cred_locked(clp);
266         spin_unlock(&clp->cl_lock);
267         return cred;
268 }
269
270 #endif /* CONFIG_NFS_V4_1 */
271
272 static struct rpc_cred *
273 nfs4_get_setclientid_cred_server(struct nfs_server *server)
274 {
275         struct nfs_client *clp = server->nfs_client;
276         struct rpc_cred *cred = NULL;
277         struct nfs4_state_owner *sp;
278         struct rb_node *pos;
279
280         spin_lock(&clp->cl_lock);
281         pos = rb_first(&server->state_owners);
282         if (pos != NULL) {
283                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
284                 cred = get_rpccred(sp->so_cred);
285         }
286         spin_unlock(&clp->cl_lock);
287         return cred;
288 }
289
290 /**
291  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
292  * @clp: client state handle
293  *
294  * Returns an rpc_cred with reference count bumped, or NULL.
295  */
296 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
297 {
298         struct nfs_server *server;
299         struct rpc_cred *cred;
300
301         spin_lock(&clp->cl_lock);
302         cred = nfs4_get_machine_cred_locked(clp);
303         spin_unlock(&clp->cl_lock);
304         if (cred != NULL)
305                 goto out;
306
307         rcu_read_lock();
308         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
309                 cred = nfs4_get_setclientid_cred_server(server);
310                 if (cred != NULL)
311                         break;
312         }
313         rcu_read_unlock();
314
315 out:
316         return cred;
317 }
318
319 static struct nfs4_state_owner *
320 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
321 {
322         struct rb_node **p = &server->state_owners.rb_node,
323                        *parent = NULL;
324         struct nfs4_state_owner *sp;
325
326         while (*p != NULL) {
327                 parent = *p;
328                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
329
330                 if (cred < sp->so_cred)
331                         p = &parent->rb_left;
332                 else if (cred > sp->so_cred)
333                         p = &parent->rb_right;
334                 else {
335                         if (!list_empty(&sp->so_lru))
336                                 list_del_init(&sp->so_lru);
337                         atomic_inc(&sp->so_count);
338                         return sp;
339                 }
340         }
341         return NULL;
342 }
343
344 static struct nfs4_state_owner *
345 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
346 {
347         struct nfs_server *server = new->so_server;
348         struct rb_node **p = &server->state_owners.rb_node,
349                        *parent = NULL;
350         struct nfs4_state_owner *sp;
351         int err;
352
353         while (*p != NULL) {
354                 parent = *p;
355                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
356
357                 if (new->so_cred < sp->so_cred)
358                         p = &parent->rb_left;
359                 else if (new->so_cred > sp->so_cred)
360                         p = &parent->rb_right;
361                 else {
362                         if (!list_empty(&sp->so_lru))
363                                 list_del_init(&sp->so_lru);
364                         atomic_inc(&sp->so_count);
365                         return sp;
366                 }
367         }
368         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
369         if (err)
370                 return ERR_PTR(err);
371         rb_link_node(&new->so_server_node, parent, p);
372         rb_insert_color(&new->so_server_node, &server->state_owners);
373         return new;
374 }
375
376 static void
377 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
378 {
379         struct nfs_server *server = sp->so_server;
380
381         if (!RB_EMPTY_NODE(&sp->so_server_node))
382                 rb_erase(&sp->so_server_node, &server->state_owners);
383         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
384 }
385
386 static void
387 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
388 {
389         sc->flags = 0;
390         sc->counter = 0;
391         spin_lock_init(&sc->lock);
392         INIT_LIST_HEAD(&sc->list);
393         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
394 }
395
396 static void
397 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
398 {
399         rpc_destroy_wait_queue(&sc->wait);
400 }
401
402 /*
403  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
404  * create a new state_owner.
405  *
406  */
407 static struct nfs4_state_owner *
408 nfs4_alloc_state_owner(struct nfs_server *server,
409                 struct rpc_cred *cred,
410                 gfp_t gfp_flags)
411 {
412         struct nfs4_state_owner *sp;
413
414         sp = kzalloc(sizeof(*sp), gfp_flags);
415         if (!sp)
416                 return NULL;
417         sp->so_server = server;
418         sp->so_cred = get_rpccred(cred);
419         spin_lock_init(&sp->so_lock);
420         INIT_LIST_HEAD(&sp->so_states);
421         nfs4_init_seqid_counter(&sp->so_seqid);
422         atomic_set(&sp->so_count, 1);
423         INIT_LIST_HEAD(&sp->so_lru);
424         return sp;
425 }
426
427 static void
428 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
429 {
430         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
431                 struct nfs_server *server = sp->so_server;
432                 struct nfs_client *clp = server->nfs_client;
433
434                 spin_lock(&clp->cl_lock);
435                 rb_erase(&sp->so_server_node, &server->state_owners);
436                 RB_CLEAR_NODE(&sp->so_server_node);
437                 spin_unlock(&clp->cl_lock);
438         }
439 }
440
441 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
442 {
443         nfs4_destroy_seqid_counter(&sp->so_seqid);
444         put_rpccred(sp->so_cred);
445         kfree(sp);
446 }
447
448 static void nfs4_gc_state_owners(struct nfs_server *server)
449 {
450         struct nfs_client *clp = server->nfs_client;
451         struct nfs4_state_owner *sp, *tmp;
452         unsigned long time_min, time_max;
453         LIST_HEAD(doomed);
454
455         spin_lock(&clp->cl_lock);
456         time_max = jiffies;
457         time_min = (long)time_max - (long)clp->cl_lease_time;
458         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
459                 /* NB: LRU is sorted so that oldest is at the head */
460                 if (time_in_range(sp->so_expires, time_min, time_max))
461                         break;
462                 list_move(&sp->so_lru, &doomed);
463                 nfs4_remove_state_owner_locked(sp);
464         }
465         spin_unlock(&clp->cl_lock);
466
467         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
468                 list_del(&sp->so_lru);
469                 nfs4_free_state_owner(sp);
470         }
471 }
472
473 /**
474  * nfs4_get_state_owner - Look up a state owner given a credential
475  * @server: nfs_server to search
476  * @cred: RPC credential to match
477  *
478  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
479  */
480 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
481                                               struct rpc_cred *cred,
482                                               gfp_t gfp_flags)
483 {
484         struct nfs_client *clp = server->nfs_client;
485         struct nfs4_state_owner *sp, *new;
486
487         spin_lock(&clp->cl_lock);
488         sp = nfs4_find_state_owner_locked(server, cred);
489         spin_unlock(&clp->cl_lock);
490         if (sp != NULL)
491                 goto out;
492         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
493         if (new == NULL)
494                 goto out;
495         do {
496                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
497                         break;
498                 spin_lock(&clp->cl_lock);
499                 sp = nfs4_insert_state_owner_locked(new);
500                 spin_unlock(&clp->cl_lock);
501         } while (sp == ERR_PTR(-EAGAIN));
502         if (sp != new)
503                 nfs4_free_state_owner(new);
504 out:
505         nfs4_gc_state_owners(server);
506         return sp;
507 }
508
509 /**
510  * nfs4_put_state_owner - Release a nfs4_state_owner
511  * @sp: state owner data to release
512  */
513 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
514 {
515         struct nfs_server *server = sp->so_server;
516         struct nfs_client *clp = server->nfs_client;
517
518         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
519                 return;
520
521         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
522                 sp->so_expires = jiffies;
523                 list_add_tail(&sp->so_lru, &server->state_owners_lru);
524                 spin_unlock(&clp->cl_lock);
525         } else {
526                 nfs4_remove_state_owner_locked(sp);
527                 spin_unlock(&clp->cl_lock);
528                 nfs4_free_state_owner(sp);
529         }
530 }
531
532 /**
533  * nfs4_purge_state_owners - Release all cached state owners
534  * @server: nfs_server with cached state owners to release
535  *
536  * Called at umount time.  Remaining state owners will be on
537  * the LRU with ref count of zero.
538  */
539 void nfs4_purge_state_owners(struct nfs_server *server)
540 {
541         struct nfs_client *clp = server->nfs_client;
542         struct nfs4_state_owner *sp, *tmp;
543         LIST_HEAD(doomed);
544
545         spin_lock(&clp->cl_lock);
546         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
547                 list_move(&sp->so_lru, &doomed);
548                 nfs4_remove_state_owner_locked(sp);
549         }
550         spin_unlock(&clp->cl_lock);
551
552         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
553                 list_del(&sp->so_lru);
554                 nfs4_free_state_owner(sp);
555         }
556 }
557
558 static struct nfs4_state *
559 nfs4_alloc_open_state(void)
560 {
561         struct nfs4_state *state;
562
563         state = kzalloc(sizeof(*state), GFP_NOFS);
564         if (!state)
565                 return NULL;
566         atomic_set(&state->count, 1);
567         INIT_LIST_HEAD(&state->lock_states);
568         spin_lock_init(&state->state_lock);
569         seqlock_init(&state->seqlock);
570         return state;
571 }
572
573 void
574 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
575 {
576         if (state->state == fmode)
577                 return;
578         /* NB! List reordering - see the reclaim code for why.  */
579         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
580                 if (fmode & FMODE_WRITE)
581                         list_move(&state->open_states, &state->owner->so_states);
582                 else
583                         list_move_tail(&state->open_states, &state->owner->so_states);
584         }
585         state->state = fmode;
586 }
587
588 static struct nfs4_state *
589 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
590 {
591         struct nfs_inode *nfsi = NFS_I(inode);
592         struct nfs4_state *state;
593
594         list_for_each_entry(state, &nfsi->open_states, inode_states) {
595                 if (state->owner != owner)
596                         continue;
597                 if (atomic_inc_not_zero(&state->count))
598                         return state;
599         }
600         return NULL;
601 }
602
603 static void
604 nfs4_free_open_state(struct nfs4_state *state)
605 {
606         kfree(state);
607 }
608
609 struct nfs4_state *
610 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
611 {
612         struct nfs4_state *state, *new;
613         struct nfs_inode *nfsi = NFS_I(inode);
614
615         spin_lock(&inode->i_lock);
616         state = __nfs4_find_state_byowner(inode, owner);
617         spin_unlock(&inode->i_lock);
618         if (state)
619                 goto out;
620         new = nfs4_alloc_open_state();
621         spin_lock(&owner->so_lock);
622         spin_lock(&inode->i_lock);
623         state = __nfs4_find_state_byowner(inode, owner);
624         if (state == NULL && new != NULL) {
625                 state = new;
626                 state->owner = owner;
627                 atomic_inc(&owner->so_count);
628                 list_add(&state->inode_states, &nfsi->open_states);
629                 ihold(inode);
630                 state->inode = inode;
631                 spin_unlock(&inode->i_lock);
632                 /* Note: The reclaim code dictates that we add stateless
633                  * and read-only stateids to the end of the list */
634                 list_add_tail(&state->open_states, &owner->so_states);
635                 spin_unlock(&owner->so_lock);
636         } else {
637                 spin_unlock(&inode->i_lock);
638                 spin_unlock(&owner->so_lock);
639                 if (new)
640                         nfs4_free_open_state(new);
641         }
642 out:
643         return state;
644 }
645
646 void nfs4_put_open_state(struct nfs4_state *state)
647 {
648         struct inode *inode = state->inode;
649         struct nfs4_state_owner *owner = state->owner;
650
651         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
652                 return;
653         spin_lock(&inode->i_lock);
654         list_del(&state->inode_states);
655         list_del(&state->open_states);
656         spin_unlock(&inode->i_lock);
657         spin_unlock(&owner->so_lock);
658         iput(inode);
659         nfs4_free_open_state(state);
660         nfs4_put_state_owner(owner);
661 }
662
663 /*
664  * Close the current file.
665  */
666 static void __nfs4_close(struct nfs4_state *state,
667                 fmode_t fmode, gfp_t gfp_mask, int wait)
668 {
669         struct nfs4_state_owner *owner = state->owner;
670         int call_close = 0;
671         fmode_t newstate;
672
673         atomic_inc(&owner->so_count);
674         /* Protect against nfs4_find_state() */
675         spin_lock(&owner->so_lock);
676         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
677                 case FMODE_READ:
678                         state->n_rdonly--;
679                         break;
680                 case FMODE_WRITE:
681                         state->n_wronly--;
682                         break;
683                 case FMODE_READ|FMODE_WRITE:
684                         state->n_rdwr--;
685         }
686         newstate = FMODE_READ|FMODE_WRITE;
687         if (state->n_rdwr == 0) {
688                 if (state->n_rdonly == 0) {
689                         newstate &= ~FMODE_READ;
690                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
691                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
692                 }
693                 if (state->n_wronly == 0) {
694                         newstate &= ~FMODE_WRITE;
695                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
696                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
697                 }
698                 if (newstate == 0)
699                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
700         }
701         nfs4_state_set_mode_locked(state, newstate);
702         spin_unlock(&owner->so_lock);
703
704         if (!call_close) {
705                 nfs4_put_open_state(state);
706                 nfs4_put_state_owner(owner);
707         } else {
708                 bool roc = pnfs_roc(state->inode);
709
710                 nfs4_do_close(state, gfp_mask, wait, roc);
711         }
712 }
713
714 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
715 {
716         __nfs4_close(state, fmode, GFP_NOFS, 0);
717 }
718
719 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
720 {
721         __nfs4_close(state, fmode, GFP_KERNEL, 1);
722 }
723
724 /*
725  * Search the state->lock_states for an existing lock_owner
726  * that is compatible with current->files
727  */
728 static struct nfs4_lock_state *
729 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
730 {
731         struct nfs4_lock_state *pos;
732         list_for_each_entry(pos, &state->lock_states, ls_locks) {
733                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
734                         continue;
735                 switch (pos->ls_owner.lo_type) {
736                 case NFS4_POSIX_LOCK_TYPE:
737                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
738                                 continue;
739                         break;
740                 case NFS4_FLOCK_LOCK_TYPE:
741                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
742                                 continue;
743                 }
744                 atomic_inc(&pos->ls_count);
745                 return pos;
746         }
747         return NULL;
748 }
749
750 /*
751  * Return a compatible lock_state. If no initialized lock_state structure
752  * exists, return an uninitialized one.
753  *
754  */
755 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
756 {
757         struct nfs4_lock_state *lsp;
758         struct nfs_server *server = state->owner->so_server;
759
760         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
761         if (lsp == NULL)
762                 return NULL;
763         nfs4_init_seqid_counter(&lsp->ls_seqid);
764         atomic_set(&lsp->ls_count, 1);
765         lsp->ls_state = state;
766         lsp->ls_owner.lo_type = type;
767         switch (lsp->ls_owner.lo_type) {
768         case NFS4_FLOCK_LOCK_TYPE:
769                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
770                 break;
771         case NFS4_POSIX_LOCK_TYPE:
772                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
773                 break;
774         default:
775                 goto out_free;
776         }
777         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
778         if (lsp->ls_seqid.owner_id < 0)
779                 goto out_free;
780         INIT_LIST_HEAD(&lsp->ls_locks);
781         return lsp;
782 out_free:
783         kfree(lsp);
784         return NULL;
785 }
786
787 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
788 {
789         struct nfs_server *server = lsp->ls_state->owner->so_server;
790
791         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
792         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
793         kfree(lsp);
794 }
795
796 /*
797  * Return a compatible lock_state. If no initialized lock_state structure
798  * exists, return an uninitialized one.
799  *
800  */
801 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
802 {
803         struct nfs4_lock_state *lsp, *new = NULL;
804         
805         for(;;) {
806                 spin_lock(&state->state_lock);
807                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
808                 if (lsp != NULL)
809                         break;
810                 if (new != NULL) {
811                         list_add(&new->ls_locks, &state->lock_states);
812                         set_bit(LK_STATE_IN_USE, &state->flags);
813                         lsp = new;
814                         new = NULL;
815                         break;
816                 }
817                 spin_unlock(&state->state_lock);
818                 new = nfs4_alloc_lock_state(state, owner, pid, type);
819                 if (new == NULL)
820                         return NULL;
821         }
822         spin_unlock(&state->state_lock);
823         if (new != NULL)
824                 nfs4_free_lock_state(new);
825         return lsp;
826 }
827
828 /*
829  * Release reference to lock_state, and free it if we see that
830  * it is no longer in use
831  */
832 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
833 {
834         struct nfs4_state *state;
835
836         if (lsp == NULL)
837                 return;
838         state = lsp->ls_state;
839         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
840                 return;
841         list_del(&lsp->ls_locks);
842         if (list_empty(&state->lock_states))
843                 clear_bit(LK_STATE_IN_USE, &state->flags);
844         spin_unlock(&state->state_lock);
845         if (lsp->ls_flags & NFS_LOCK_INITIALIZED)
846                 nfs4_release_lockowner(lsp);
847         nfs4_free_lock_state(lsp);
848 }
849
850 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
851 {
852         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
853
854         dst->fl_u.nfs4_fl.owner = lsp;
855         atomic_inc(&lsp->ls_count);
856 }
857
858 static void nfs4_fl_release_lock(struct file_lock *fl)
859 {
860         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
861 }
862
863 static const struct file_lock_operations nfs4_fl_lock_ops = {
864         .fl_copy_lock = nfs4_fl_copy_lock,
865         .fl_release_private = nfs4_fl_release_lock,
866 };
867
868 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
869 {
870         struct nfs4_lock_state *lsp;
871
872         if (fl->fl_ops != NULL)
873                 return 0;
874         if (fl->fl_flags & FL_POSIX)
875                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
876         else if (fl->fl_flags & FL_FLOCK)
877                 lsp = nfs4_get_lock_state(state, 0, fl->fl_pid, NFS4_FLOCK_LOCK_TYPE);
878         else
879                 return -EINVAL;
880         if (lsp == NULL)
881                 return -ENOMEM;
882         fl->fl_u.nfs4_fl.owner = lsp;
883         fl->fl_ops = &nfs4_fl_lock_ops;
884         return 0;
885 }
886
887 /*
888  * Byte-range lock aware utility to initialize the stateid of read/write
889  * requests.
890  */
891 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid)
892 {
893         struct nfs4_lock_state *lsp;
894         int seq;
895
896         do {
897                 seq = read_seqbegin(&state->seqlock);
898                 memcpy(dst, &state->stateid, sizeof(*dst));
899         } while (read_seqretry(&state->seqlock, seq));
900         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
901                 return;
902
903         spin_lock(&state->state_lock);
904         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
905         if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
906                 memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
907         spin_unlock(&state->state_lock);
908         nfs4_put_lock_state(lsp);
909 }
910
911 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
912 {
913         struct nfs_seqid *new;
914
915         new = kmalloc(sizeof(*new), gfp_mask);
916         if (new != NULL) {
917                 new->sequence = counter;
918                 INIT_LIST_HEAD(&new->list);
919                 new->task = NULL;
920         }
921         return new;
922 }
923
924 void nfs_release_seqid(struct nfs_seqid *seqid)
925 {
926         struct nfs_seqid_counter *sequence;
927
928         if (list_empty(&seqid->list))
929                 return;
930         sequence = seqid->sequence;
931         spin_lock(&sequence->lock);
932         list_del_init(&seqid->list);
933         if (!list_empty(&sequence->list)) {
934                 struct nfs_seqid *next;
935
936                 next = list_first_entry(&sequence->list,
937                                 struct nfs_seqid, list);
938                 rpc_wake_up_queued_task(&sequence->wait, next->task);
939         }
940         spin_unlock(&sequence->lock);
941 }
942
943 void nfs_free_seqid(struct nfs_seqid *seqid)
944 {
945         nfs_release_seqid(seqid);
946         kfree(seqid);
947 }
948
949 /*
950  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
951  * failed with a seqid incrementing error -
952  * see comments nfs_fs.h:seqid_mutating_error()
953  */
954 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
955 {
956         BUG_ON(list_first_entry(&seqid->sequence->list, struct nfs_seqid, list) != seqid);
957         switch (status) {
958                 case 0:
959                         break;
960                 case -NFS4ERR_BAD_SEQID:
961                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
962                                 return;
963                         printk(KERN_WARNING "NFS: v4 server returned a bad"
964                                         " sequence-id error on an"
965                                         " unconfirmed sequence %p!\n",
966                                         seqid->sequence);
967                 case -NFS4ERR_STALE_CLIENTID:
968                 case -NFS4ERR_STALE_STATEID:
969                 case -NFS4ERR_BAD_STATEID:
970                 case -NFS4ERR_BADXDR:
971                 case -NFS4ERR_RESOURCE:
972                 case -NFS4ERR_NOFILEHANDLE:
973                         /* Non-seqid mutating errors */
974                         return;
975         };
976         /*
977          * Note: no locking needed as we are guaranteed to be first
978          * on the sequence list
979          */
980         seqid->sequence->counter++;
981 }
982
983 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
984 {
985         struct nfs4_state_owner *sp = container_of(seqid->sequence,
986                                         struct nfs4_state_owner, so_seqid);
987         struct nfs_server *server = sp->so_server;
988
989         if (status == -NFS4ERR_BAD_SEQID)
990                 nfs4_drop_state_owner(sp);
991         if (!nfs4_has_session(server->nfs_client))
992                 nfs_increment_seqid(status, seqid);
993 }
994
995 /*
996  * Increment the seqid if the LOCK/LOCKU succeeded, or
997  * failed with a seqid incrementing error -
998  * see comments nfs_fs.h:seqid_mutating_error()
999  */
1000 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1001 {
1002         nfs_increment_seqid(status, seqid);
1003 }
1004
1005 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1006 {
1007         struct nfs_seqid_counter *sequence = seqid->sequence;
1008         int status = 0;
1009
1010         spin_lock(&sequence->lock);
1011         seqid->task = task;
1012         if (list_empty(&seqid->list))
1013                 list_add_tail(&seqid->list, &sequence->list);
1014         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1015                 goto unlock;
1016         rpc_sleep_on(&sequence->wait, task, NULL);
1017         status = -EAGAIN;
1018 unlock:
1019         spin_unlock(&sequence->lock);
1020         return status;
1021 }
1022
1023 static int nfs4_run_state_manager(void *);
1024
1025 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1026 {
1027         smp_mb__before_clear_bit();
1028         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1029         smp_mb__after_clear_bit();
1030         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1031         rpc_wake_up(&clp->cl_rpcwaitq);
1032 }
1033
1034 /*
1035  * Schedule the nfs_client asynchronous state management routine
1036  */
1037 void nfs4_schedule_state_manager(struct nfs_client *clp)
1038 {
1039         struct task_struct *task;
1040         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1041
1042         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1043                 return;
1044         __module_get(THIS_MODULE);
1045         atomic_inc(&clp->cl_count);
1046
1047         /* The rcu_read_lock() is not strictly necessary, as the state
1048          * manager is the only thread that ever changes the rpc_xprt
1049          * after it's initialized.  At this point, we're single threaded. */
1050         rcu_read_lock();
1051         snprintf(buf, sizeof(buf), "%s-manager",
1052                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1053         rcu_read_unlock();
1054         task = kthread_run(nfs4_run_state_manager, clp, buf);
1055         if (IS_ERR(task)) {
1056                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1057                         __func__, PTR_ERR(task));
1058                 nfs4_clear_state_manager_bit(clp);
1059                 nfs_put_client(clp);
1060                 module_put(THIS_MODULE);
1061         }
1062 }
1063
1064 /*
1065  * Schedule a lease recovery attempt
1066  */
1067 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1068 {
1069         if (!clp)
1070                 return;
1071         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1072                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1073         nfs4_schedule_state_manager(clp);
1074 }
1075
1076 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1077 {
1078         nfs_handle_cb_pathdown(clp);
1079         nfs4_schedule_state_manager(clp);
1080 }
1081
1082 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1083 {
1084
1085         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1086         /* Don't recover state that expired before the reboot */
1087         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1088                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1089                 return 0;
1090         }
1091         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1092         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1093         return 1;
1094 }
1095
1096 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1097 {
1098         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1099         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1100         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1101         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1102         return 1;
1103 }
1104
1105 void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1106 {
1107         struct nfs_client *clp = server->nfs_client;
1108
1109         if (test_and_clear_bit(NFS_DELEGATED_STATE, &state->flags))
1110                 nfs_async_inode_return_delegation(state->inode, &state->stateid);
1111         nfs4_state_mark_reclaim_nograce(clp, state);
1112         nfs4_schedule_state_manager(clp);
1113 }
1114
1115 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1116 {
1117         struct inode *inode = state->inode;
1118         struct nfs_inode *nfsi = NFS_I(inode);
1119         struct file_lock *fl;
1120         int status = 0;
1121
1122         if (inode->i_flock == NULL)
1123                 return 0;
1124
1125         /* Guard against delegation returns and new lock/unlock calls */
1126         down_write(&nfsi->rwsem);
1127         /* Protect inode->i_flock using the BKL */
1128         lock_flocks();
1129         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1130                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1131                         continue;
1132                 if (nfs_file_open_context(fl->fl_file)->state != state)
1133                         continue;
1134                 unlock_flocks();
1135                 status = ops->recover_lock(state, fl);
1136                 switch (status) {
1137                         case 0:
1138                                 break;
1139                         case -ESTALE:
1140                         case -NFS4ERR_ADMIN_REVOKED:
1141                         case -NFS4ERR_STALE_STATEID:
1142                         case -NFS4ERR_BAD_STATEID:
1143                         case -NFS4ERR_EXPIRED:
1144                         case -NFS4ERR_NO_GRACE:
1145                         case -NFS4ERR_STALE_CLIENTID:
1146                         case -NFS4ERR_BADSESSION:
1147                         case -NFS4ERR_BADSLOT:
1148                         case -NFS4ERR_BAD_HIGH_SLOT:
1149                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1150                                 goto out;
1151                         default:
1152                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1153                                         "Zeroing state\n", __func__, status);
1154                         case -ENOMEM:
1155                         case -NFS4ERR_DENIED:
1156                         case -NFS4ERR_RECLAIM_BAD:
1157                         case -NFS4ERR_RECLAIM_CONFLICT:
1158                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1159                                 status = 0;
1160                 }
1161                 lock_flocks();
1162         }
1163         unlock_flocks();
1164 out:
1165         up_write(&nfsi->rwsem);
1166         return status;
1167 }
1168
1169 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1170 {
1171         struct nfs4_state *state;
1172         struct nfs4_lock_state *lock;
1173         int status = 0;
1174
1175         /* Note: we rely on the sp->so_states list being ordered 
1176          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1177          * states first.
1178          * This is needed to ensure that the server won't give us any
1179          * read delegations that we have to return if, say, we are
1180          * recovering after a network partition or a reboot from a
1181          * server that doesn't support a grace period.
1182          */
1183 restart:
1184         spin_lock(&sp->so_lock);
1185         list_for_each_entry(state, &sp->so_states, open_states) {
1186                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1187                         continue;
1188                 if (state->state == 0)
1189                         continue;
1190                 atomic_inc(&state->count);
1191                 spin_unlock(&sp->so_lock);
1192                 status = ops->recover_open(sp, state);
1193                 if (status >= 0) {
1194                         status = nfs4_reclaim_locks(state, ops);
1195                         if (status >= 0) {
1196                                 spin_lock(&state->state_lock);
1197                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1198                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1199                                                 printk("NFS: %s: Lock reclaim "
1200                                                         "failed!\n", __func__);
1201                                 }
1202                                 spin_unlock(&state->state_lock);
1203                                 nfs4_put_open_state(state);
1204                                 goto restart;
1205                         }
1206                 }
1207                 switch (status) {
1208                         default:
1209                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1210                                         "Zeroing state\n", __func__, status);
1211                         case -ENOENT:
1212                         case -ENOMEM:
1213                         case -ESTALE:
1214                                 /*
1215                                  * Open state on this file cannot be recovered
1216                                  * All we can do is revert to using the zero stateid.
1217                                  */
1218                                 memset(state->stateid.data, 0,
1219                                         sizeof(state->stateid.data));
1220                                 /* Mark the file as being 'closed' */
1221                                 state->state = 0;
1222                                 break;
1223                         case -EKEYEXPIRED:
1224                                 /*
1225                                  * User RPCSEC_GSS context has expired.
1226                                  * We cannot recover this stateid now, so
1227                                  * skip it and allow recovery thread to
1228                                  * proceed.
1229                                  */
1230                                 break;
1231                         case -NFS4ERR_ADMIN_REVOKED:
1232                         case -NFS4ERR_STALE_STATEID:
1233                         case -NFS4ERR_BAD_STATEID:
1234                         case -NFS4ERR_RECLAIM_BAD:
1235                         case -NFS4ERR_RECLAIM_CONFLICT:
1236                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1237                                 break;
1238                         case -NFS4ERR_EXPIRED:
1239                         case -NFS4ERR_NO_GRACE:
1240                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1241                         case -NFS4ERR_STALE_CLIENTID:
1242                         case -NFS4ERR_BADSESSION:
1243                         case -NFS4ERR_BADSLOT:
1244                         case -NFS4ERR_BAD_HIGH_SLOT:
1245                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1246                                 goto out_err;
1247                 }
1248                 nfs4_put_open_state(state);
1249                 goto restart;
1250         }
1251         spin_unlock(&sp->so_lock);
1252         return 0;
1253 out_err:
1254         nfs4_put_open_state(state);
1255         return status;
1256 }
1257
1258 static void nfs4_clear_open_state(struct nfs4_state *state)
1259 {
1260         struct nfs4_lock_state *lock;
1261
1262         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1263         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1264         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1265         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1266         spin_lock(&state->state_lock);
1267         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1268                 lock->ls_seqid.flags = 0;
1269                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1270         }
1271         spin_unlock(&state->state_lock);
1272 }
1273
1274 static void nfs4_reset_seqids(struct nfs_server *server,
1275         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1276 {
1277         struct nfs_client *clp = server->nfs_client;
1278         struct nfs4_state_owner *sp;
1279         struct rb_node *pos;
1280         struct nfs4_state *state;
1281
1282         spin_lock(&clp->cl_lock);
1283         for (pos = rb_first(&server->state_owners);
1284              pos != NULL;
1285              pos = rb_next(pos)) {
1286                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1287                 sp->so_seqid.flags = 0;
1288                 spin_lock(&sp->so_lock);
1289                 list_for_each_entry(state, &sp->so_states, open_states) {
1290                         if (mark_reclaim(clp, state))
1291                                 nfs4_clear_open_state(state);
1292                 }
1293                 spin_unlock(&sp->so_lock);
1294         }
1295         spin_unlock(&clp->cl_lock);
1296 }
1297
1298 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1299         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1300 {
1301         struct nfs_server *server;
1302
1303         rcu_read_lock();
1304         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1305                 nfs4_reset_seqids(server, mark_reclaim);
1306         rcu_read_unlock();
1307 }
1308
1309 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1310 {
1311         /* Mark all delegations for reclaim */
1312         nfs_delegation_mark_reclaim(clp);
1313         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1314 }
1315
1316 static void nfs4_reclaim_complete(struct nfs_client *clp,
1317                                  const struct nfs4_state_recovery_ops *ops)
1318 {
1319         /* Notify the server we're done reclaiming our state */
1320         if (ops->reclaim_complete)
1321                 (void)ops->reclaim_complete(clp);
1322 }
1323
1324 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1325 {
1326         struct nfs_client *clp = server->nfs_client;
1327         struct nfs4_state_owner *sp;
1328         struct rb_node *pos;
1329         struct nfs4_state *state;
1330
1331         spin_lock(&clp->cl_lock);
1332         for (pos = rb_first(&server->state_owners);
1333              pos != NULL;
1334              pos = rb_next(pos)) {
1335                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1336                 spin_lock(&sp->so_lock);
1337                 list_for_each_entry(state, &sp->so_states, open_states) {
1338                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1339                                                 &state->flags))
1340                                 continue;
1341                         nfs4_state_mark_reclaim_nograce(clp, state);
1342                 }
1343                 spin_unlock(&sp->so_lock);
1344         }
1345         spin_unlock(&clp->cl_lock);
1346 }
1347
1348 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1349 {
1350         struct nfs_server *server;
1351
1352         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1353                 return 0;
1354
1355         rcu_read_lock();
1356         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1357                 nfs4_clear_reclaim_server(server);
1358         rcu_read_unlock();
1359
1360         nfs_delegation_reap_unclaimed(clp);
1361         return 1;
1362 }
1363
1364 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1365 {
1366         if (!nfs4_state_clear_reclaim_reboot(clp))
1367                 return;
1368         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1369 }
1370
1371 static void nfs_delegation_clear_all(struct nfs_client *clp)
1372 {
1373         nfs_delegation_mark_reclaim(clp);
1374         nfs_delegation_reap_unclaimed(clp);
1375 }
1376
1377 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1378 {
1379         nfs_delegation_clear_all(clp);
1380         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1381 }
1382
1383 static void nfs4_warn_keyexpired(const char *s)
1384 {
1385         printk_ratelimited(KERN_WARNING "Error: state manager"
1386                         " encountered RPCSEC_GSS session"
1387                         " expired against NFSv4 server %s.\n",
1388                         s);
1389 }
1390
1391 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1392 {
1393         switch (error) {
1394                 case 0:
1395                         break;
1396                 case -NFS4ERR_CB_PATH_DOWN:
1397                         nfs_handle_cb_pathdown(clp);
1398                         break;
1399                 case -NFS4ERR_NO_GRACE:
1400                         nfs4_state_end_reclaim_reboot(clp);
1401                         break;
1402                 case -NFS4ERR_STALE_CLIENTID:
1403                 case -NFS4ERR_LEASE_MOVED:
1404                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1405                         nfs4_state_clear_reclaim_reboot(clp);
1406                         nfs4_state_start_reclaim_reboot(clp);
1407                         break;
1408                 case -NFS4ERR_EXPIRED:
1409                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1410                         nfs4_state_start_reclaim_nograce(clp);
1411                         break;
1412                 case -NFS4ERR_BADSESSION:
1413                 case -NFS4ERR_BADSLOT:
1414                 case -NFS4ERR_BAD_HIGH_SLOT:
1415                 case -NFS4ERR_DEADSESSION:
1416                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1417                 case -NFS4ERR_SEQ_FALSE_RETRY:
1418                 case -NFS4ERR_SEQ_MISORDERED:
1419                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1420                         /* Zero session reset errors */
1421                         break;
1422                 case -EKEYEXPIRED:
1423                         /* Nothing we can do */
1424                         nfs4_warn_keyexpired(clp->cl_hostname);
1425                         break;
1426                 default:
1427                         return error;
1428         }
1429         return 0;
1430 }
1431
1432 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1433 {
1434         struct nfs4_state_owner *sp;
1435         struct nfs_server *server;
1436         struct rb_node *pos;
1437         int status = 0;
1438
1439 restart:
1440         rcu_read_lock();
1441         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1442                 nfs4_purge_state_owners(server);
1443                 spin_lock(&clp->cl_lock);
1444                 for (pos = rb_first(&server->state_owners);
1445                      pos != NULL;
1446                      pos = rb_next(pos)) {
1447                         sp = rb_entry(pos,
1448                                 struct nfs4_state_owner, so_server_node);
1449                         if (!test_and_clear_bit(ops->owner_flag_bit,
1450                                                         &sp->so_flags))
1451                                 continue;
1452                         atomic_inc(&sp->so_count);
1453                         spin_unlock(&clp->cl_lock);
1454                         rcu_read_unlock();
1455
1456                         status = nfs4_reclaim_open_state(sp, ops);
1457                         if (status < 0) {
1458                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1459                                 nfs4_put_state_owner(sp);
1460                                 return nfs4_recovery_handle_error(clp, status);
1461                         }
1462
1463                         nfs4_put_state_owner(sp);
1464                         goto restart;
1465                 }
1466                 spin_unlock(&clp->cl_lock);
1467         }
1468         rcu_read_unlock();
1469         return status;
1470 }
1471
1472 static int nfs4_check_lease(struct nfs_client *clp)
1473 {
1474         struct rpc_cred *cred;
1475         const struct nfs4_state_maintenance_ops *ops =
1476                 clp->cl_mvops->state_renewal_ops;
1477         int status;
1478
1479         /* Is the client already known to have an expired lease? */
1480         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1481                 return 0;
1482         spin_lock(&clp->cl_lock);
1483         cred = ops->get_state_renewal_cred_locked(clp);
1484         spin_unlock(&clp->cl_lock);
1485         if (cred == NULL) {
1486                 cred = nfs4_get_setclientid_cred(clp);
1487                 status = -ENOKEY;
1488                 if (cred == NULL)
1489                         goto out;
1490         }
1491         status = ops->renew_lease(clp, cred);
1492         put_rpccred(cred);
1493 out:
1494         return nfs4_recovery_handle_error(clp, status);
1495 }
1496
1497 static int nfs4_reclaim_lease(struct nfs_client *clp)
1498 {
1499         struct rpc_cred *cred;
1500         const struct nfs4_state_recovery_ops *ops =
1501                 clp->cl_mvops->reboot_recovery_ops;
1502         int status = -ENOENT;
1503
1504         cred = ops->get_clid_cred(clp);
1505         if (cred != NULL) {
1506                 status = ops->establish_clid(clp, cred);
1507                 put_rpccred(cred);
1508                 /* Handle case where the user hasn't set up machine creds */
1509                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1510                         nfs4_clear_machine_cred(clp);
1511                         status = -EAGAIN;
1512                 }
1513                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1514                         status = -EPROTONOSUPPORT;
1515         }
1516         return status;
1517 }
1518
1519 #ifdef CONFIG_NFS_V4_1
1520 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1521 {
1522         struct nfs_client *clp = session->clp;
1523
1524         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1525         nfs4_schedule_lease_recovery(clp);
1526 }
1527 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1528
1529 void nfs41_handle_recall_slot(struct nfs_client *clp)
1530 {
1531         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1532         nfs4_schedule_state_manager(clp);
1533 }
1534
1535 static void nfs4_reset_all_state(struct nfs_client *clp)
1536 {
1537         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1538                 clp->cl_boot_time = CURRENT_TIME;
1539                 nfs4_state_start_reclaim_nograce(clp);
1540                 nfs4_schedule_state_manager(clp);
1541         }
1542 }
1543
1544 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1545 {
1546         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1547                 nfs4_state_start_reclaim_reboot(clp);
1548                 nfs4_schedule_state_manager(clp);
1549         }
1550 }
1551
1552 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1553 {
1554         /* Temporary */
1555         nfs4_reset_all_state(clp);
1556 }
1557
1558 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1559 {
1560         /* This will need to handle layouts too */
1561         nfs_expire_all_delegations(clp);
1562 }
1563
1564 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1565 {
1566         nfs_expire_all_delegations(clp);
1567         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1568                 nfs4_schedule_state_manager(clp);
1569 }
1570
1571 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1572 {
1573         if (!flags)
1574                 return;
1575         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1576                 nfs41_handle_server_reboot(clp);
1577         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1578                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1579                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1580                             SEQ4_STATUS_LEASE_MOVED))
1581                 nfs41_handle_state_revoked(clp);
1582         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1583                 nfs41_handle_recallable_state_revoked(clp);
1584         if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1585                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1586                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1587                 nfs41_handle_cb_path_down(clp);
1588 }
1589
1590 static int nfs4_reset_session(struct nfs_client *clp)
1591 {
1592         int status;
1593
1594         nfs4_begin_drain_session(clp);
1595         status = nfs4_proc_destroy_session(clp->cl_session);
1596         if (status && status != -NFS4ERR_BADSESSION &&
1597             status != -NFS4ERR_DEADSESSION) {
1598                 status = nfs4_recovery_handle_error(clp, status);
1599                 goto out;
1600         }
1601
1602         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1603         status = nfs4_proc_create_session(clp);
1604         if (status) {
1605                 status = nfs4_recovery_handle_error(clp, status);
1606                 goto out;
1607         }
1608         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1609         /* create_session negotiated new slot table */
1610         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1611
1612          /* Let the state manager reestablish state */
1613         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1614                 nfs41_setup_state_renewal(clp);
1615 out:
1616         return status;
1617 }
1618
1619 static int nfs4_recall_slot(struct nfs_client *clp)
1620 {
1621         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1622         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1623         struct nfs4_slot *new, *old;
1624         int i;
1625
1626         nfs4_begin_drain_session(clp);
1627         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1628                       GFP_NOFS);
1629         if (!new)
1630                 return -ENOMEM;
1631
1632         spin_lock(&fc_tbl->slot_tbl_lock);
1633         for (i = 0; i < fc_tbl->target_max_slots; i++)
1634                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1635         old = fc_tbl->slots;
1636         fc_tbl->slots = new;
1637         fc_tbl->max_slots = fc_tbl->target_max_slots;
1638         fc_tbl->target_max_slots = 0;
1639         fc_attrs->max_reqs = fc_tbl->max_slots;
1640         spin_unlock(&fc_tbl->slot_tbl_lock);
1641
1642         kfree(old);
1643         nfs4_end_drain_session(clp);
1644         return 0;
1645 }
1646
1647 #else /* CONFIG_NFS_V4_1 */
1648 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1649 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1650 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1651 #endif /* CONFIG_NFS_V4_1 */
1652
1653 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1654  * on EXCHANGE_ID for v4.1
1655  */
1656 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1657 {
1658         switch (status) {
1659         case -NFS4ERR_CLID_INUSE:
1660         case -NFS4ERR_STALE_CLIENTID:
1661                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1662                 break;
1663         case -NFS4ERR_DELAY:
1664         case -ETIMEDOUT:
1665         case -EAGAIN:
1666                 ssleep(1);
1667                 break;
1668
1669         case -EKEYEXPIRED:
1670                 nfs4_warn_keyexpired(clp->cl_hostname);
1671         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1672                                  * in nfs4_exchange_id */
1673         default:
1674                 return;
1675         }
1676         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1677 }
1678
1679 static void nfs4_state_manager(struct nfs_client *clp)
1680 {
1681         int status = 0;
1682
1683         /* Ensure exclusive access to NFSv4 state */
1684         do {
1685                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1686                         /* We're going to have to re-establish a clientid */
1687                         status = nfs4_reclaim_lease(clp);
1688                         if (status) {
1689                                 nfs4_set_lease_expired(clp, status);
1690                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1691                                                         &clp->cl_state))
1692                                         continue;
1693                                 if (clp->cl_cons_state ==
1694                                                         NFS_CS_SESSION_INITING)
1695                                         nfs_mark_client_ready(clp, status);
1696                                 goto out_error;
1697                         }
1698                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1699
1700                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1701                                                &clp->cl_state))
1702                                 nfs4_state_start_reclaim_nograce(clp);
1703                         else
1704                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1705                                         &clp->cl_state);
1706
1707                         pnfs_destroy_all_layouts(clp);
1708                 }
1709
1710                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1711                         status = nfs4_check_lease(clp);
1712                         if (status < 0)
1713                                 goto out_error;
1714                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1715                                 continue;
1716                 }
1717
1718                 /* Initialize or reset the session */
1719                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1720                    && nfs4_has_session(clp)) {
1721                         status = nfs4_reset_session(clp);
1722                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1723                                 continue;
1724                         if (status < 0)
1725                                 goto out_error;
1726                 }
1727
1728                 /* First recover reboot state... */
1729                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1730                         status = nfs4_do_reclaim(clp,
1731                                 clp->cl_mvops->reboot_recovery_ops);
1732                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1733                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1734                                 continue;
1735                         nfs4_state_end_reclaim_reboot(clp);
1736                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1737                                 continue;
1738                         if (status < 0)
1739                                 goto out_error;
1740                 }
1741
1742                 /* Now recover expired state... */
1743                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1744                         status = nfs4_do_reclaim(clp,
1745                                 clp->cl_mvops->nograce_recovery_ops);
1746                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1747                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1748                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1749                                 continue;
1750                         if (status < 0)
1751                                 goto out_error;
1752                 }
1753
1754                 nfs4_end_drain_session(clp);
1755                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1756                         nfs_client_return_marked_delegations(clp);
1757                         continue;
1758                 }
1759                 /* Recall session slots */
1760                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1761                    && nfs4_has_session(clp)) {
1762                         status = nfs4_recall_slot(clp);
1763                         if (status < 0)
1764                                 goto out_error;
1765                         continue;
1766                 }
1767
1768
1769                 nfs4_clear_state_manager_bit(clp);
1770                 /* Did we race with an attempt to give us more work? */
1771                 if (clp->cl_state == 0)
1772                         break;
1773                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1774                         break;
1775         } while (atomic_read(&clp->cl_count) > 1);
1776         return;
1777 out_error:
1778         printk(KERN_WARNING "NFS: state manager failed on NFSv4 server %s"
1779                         " with error %d\n", clp->cl_hostname, -status);
1780         nfs4_end_drain_session(clp);
1781         nfs4_clear_state_manager_bit(clp);
1782 }
1783
1784 static int nfs4_run_state_manager(void *ptr)
1785 {
1786         struct nfs_client *clp = ptr;
1787
1788         allow_signal(SIGKILL);
1789         nfs4_state_manager(clp);
1790         nfs_put_client(clp);
1791         module_put_and_exit(0);
1792         return 0;
1793 }
1794
1795 /*
1796  * Local variables:
1797  *  c-basic-offset: 8
1798  * End:
1799  */