NFS: Properly handle the case where the delegation is revoked
[firefly-linux-kernel-4.4.55.git] / fs / nfs / nfs4state.c
1 /*
2  *  fs/nfs/nfs4state.c
3  *
4  *  Client-side XDR for NFSv4.
5  *
6  *  Copyright (c) 2002 The Regents of the University of Michigan.
7  *  All rights reserved.
8  *
9  *  Kendrick Smith <kmsmith@umich.edu>
10  *
11  *  Redistribution and use in source and binary forms, with or without
12  *  modification, are permitted provided that the following conditions
13  *  are met:
14  *
15  *  1. Redistributions of source code must retain the above copyright
16  *     notice, this list of conditions and the following disclaimer.
17  *  2. Redistributions in binary form must reproduce the above copyright
18  *     notice, this list of conditions and the following disclaimer in the
19  *     documentation and/or other materials provided with the distribution.
20  *  3. Neither the name of the University nor the names of its
21  *     contributors may be used to endorse or promote products derived
22  *     from this software without specific prior written permission.
23  *
24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35  *
36  * Implementation of the NFSv4 state model.  For the time being,
37  * this is minimal, but will be made much more complex in a
38  * subsequent patch.
39  */
40
41 #include <linux/kernel.h>
42 #include <linux/slab.h>
43 #include <linux/fs.h>
44 #include <linux/nfs_fs.h>
45 #include <linux/nfs_idmap.h>
46 #include <linux/kthread.h>
47 #include <linux/module.h>
48 #include <linux/random.h>
49 #include <linux/ratelimit.h>
50 #include <linux/workqueue.h>
51 #include <linux/bitops.h>
52 #include <linux/jiffies.h>
53
54 #include "nfs4_fs.h"
55 #include "callback.h"
56 #include "delegation.h"
57 #include "internal.h"
58 #include "pnfs.h"
59
60 #define OPENOWNER_POOL_SIZE     8
61
62 const nfs4_stateid zero_stateid;
63
64 static LIST_HEAD(nfs4_clientid_list);
65
66 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
67 {
68         struct nfs4_setclientid_res clid = {
69                 .clientid = clp->cl_clientid,
70                 .confirm = clp->cl_confirm,
71         };
72         unsigned short port;
73         int status;
74
75         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
76                 goto do_confirm;
77         port = nfs_callback_tcpport;
78         if (clp->cl_addr.ss_family == AF_INET6)
79                 port = nfs_callback_tcpport6;
80
81         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
82         if (status != 0)
83                 goto out;
84         clp->cl_clientid = clid.clientid;
85         clp->cl_confirm = clid.confirm;
86         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
87 do_confirm:
88         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
89         if (status != 0)
90                 goto out;
91         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
92         nfs4_schedule_state_renewal(clp);
93 out:
94         return status;
95 }
96
97 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
98 {
99         struct rpc_cred *cred = NULL;
100
101         if (clp->cl_machine_cred != NULL)
102                 cred = get_rpccred(clp->cl_machine_cred);
103         return cred;
104 }
105
106 static void nfs4_clear_machine_cred(struct nfs_client *clp)
107 {
108         struct rpc_cred *cred;
109
110         spin_lock(&clp->cl_lock);
111         cred = clp->cl_machine_cred;
112         clp->cl_machine_cred = NULL;
113         spin_unlock(&clp->cl_lock);
114         if (cred != NULL)
115                 put_rpccred(cred);
116 }
117
118 static struct rpc_cred *
119 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
120 {
121         struct rpc_cred *cred = NULL;
122         struct nfs4_state_owner *sp;
123         struct rb_node *pos;
124
125         for (pos = rb_first(&server->state_owners);
126              pos != NULL;
127              pos = rb_next(pos)) {
128                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
129                 if (list_empty(&sp->so_states))
130                         continue;
131                 cred = get_rpccred(sp->so_cred);
132                 break;
133         }
134         return cred;
135 }
136
137 /**
138  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
139  * @clp: client state handle
140  *
141  * Returns an rpc_cred with reference count bumped, or NULL.
142  * Caller must hold clp->cl_lock.
143  */
144 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
145 {
146         struct rpc_cred *cred = NULL;
147         struct nfs_server *server;
148
149         rcu_read_lock();
150         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
151                 cred = nfs4_get_renew_cred_server_locked(server);
152                 if (cred != NULL)
153                         break;
154         }
155         rcu_read_unlock();
156         return cred;
157 }
158
159 #if defined(CONFIG_NFS_V4_1)
160
161 static int nfs41_setup_state_renewal(struct nfs_client *clp)
162 {
163         int status;
164         struct nfs_fsinfo fsinfo;
165
166         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
167                 nfs4_schedule_state_renewal(clp);
168                 return 0;
169         }
170
171         status = nfs4_proc_get_lease_time(clp, &fsinfo);
172         if (status == 0) {
173                 /* Update lease time and schedule renewal */
174                 spin_lock(&clp->cl_lock);
175                 clp->cl_lease_time = fsinfo.lease_time * HZ;
176                 clp->cl_last_renewal = jiffies;
177                 spin_unlock(&clp->cl_lock);
178
179                 nfs4_schedule_state_renewal(clp);
180         }
181
182         return status;
183 }
184
185 /*
186  * Back channel returns NFS4ERR_DELAY for new requests when
187  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
188  * is ended.
189  */
190 static void nfs4_end_drain_session(struct nfs_client *clp)
191 {
192         struct nfs4_session *ses = clp->cl_session;
193         struct nfs4_slot_table *tbl;
194         int max_slots;
195
196         if (ses == NULL)
197                 return;
198         tbl = &ses->fc_slot_table;
199         if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
200                 spin_lock(&tbl->slot_tbl_lock);
201                 max_slots = tbl->max_slots;
202                 while (max_slots--) {
203                         if (rpc_wake_up_first(&tbl->slot_tbl_waitq,
204                                                 nfs4_set_task_privileged,
205                                                 NULL) == NULL)
206                                 break;
207                 }
208                 spin_unlock(&tbl->slot_tbl_lock);
209         }
210 }
211
212 static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
213 {
214         spin_lock(&tbl->slot_tbl_lock);
215         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
216                 INIT_COMPLETION(tbl->complete);
217                 spin_unlock(&tbl->slot_tbl_lock);
218                 return wait_for_completion_interruptible(&tbl->complete);
219         }
220         spin_unlock(&tbl->slot_tbl_lock);
221         return 0;
222 }
223
224 static int nfs4_begin_drain_session(struct nfs_client *clp)
225 {
226         struct nfs4_session *ses = clp->cl_session;
227         int ret = 0;
228
229         set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
230         /* back channel */
231         ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
232         if (ret)
233                 return ret;
234         /* fore channel */
235         return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
236 }
237
238 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
239 {
240         int status;
241
242         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
243                 goto do_confirm;
244         nfs4_begin_drain_session(clp);
245         status = nfs4_proc_exchange_id(clp, cred);
246         if (status != 0)
247                 goto out;
248         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
249 do_confirm:
250         status = nfs4_proc_create_session(clp);
251         if (status != 0)
252                 goto out;
253         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
254         nfs41_setup_state_renewal(clp);
255         nfs_mark_client_ready(clp, NFS_CS_READY);
256 out:
257         return status;
258 }
259
260 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
261 {
262         struct rpc_cred *cred;
263
264         spin_lock(&clp->cl_lock);
265         cred = nfs4_get_machine_cred_locked(clp);
266         spin_unlock(&clp->cl_lock);
267         return cred;
268 }
269
270 #endif /* CONFIG_NFS_V4_1 */
271
272 static struct rpc_cred *
273 nfs4_get_setclientid_cred_server(struct nfs_server *server)
274 {
275         struct nfs_client *clp = server->nfs_client;
276         struct rpc_cred *cred = NULL;
277         struct nfs4_state_owner *sp;
278         struct rb_node *pos;
279
280         spin_lock(&clp->cl_lock);
281         pos = rb_first(&server->state_owners);
282         if (pos != NULL) {
283                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
284                 cred = get_rpccred(sp->so_cred);
285         }
286         spin_unlock(&clp->cl_lock);
287         return cred;
288 }
289
290 /**
291  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
292  * @clp: client state handle
293  *
294  * Returns an rpc_cred with reference count bumped, or NULL.
295  */
296 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
297 {
298         struct nfs_server *server;
299         struct rpc_cred *cred;
300
301         spin_lock(&clp->cl_lock);
302         cred = nfs4_get_machine_cred_locked(clp);
303         spin_unlock(&clp->cl_lock);
304         if (cred != NULL)
305                 goto out;
306
307         rcu_read_lock();
308         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
309                 cred = nfs4_get_setclientid_cred_server(server);
310                 if (cred != NULL)
311                         break;
312         }
313         rcu_read_unlock();
314
315 out:
316         return cred;
317 }
318
319 static struct nfs4_state_owner *
320 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
321 {
322         struct rb_node **p = &server->state_owners.rb_node,
323                        *parent = NULL;
324         struct nfs4_state_owner *sp;
325
326         while (*p != NULL) {
327                 parent = *p;
328                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
329
330                 if (cred < sp->so_cred)
331                         p = &parent->rb_left;
332                 else if (cred > sp->so_cred)
333                         p = &parent->rb_right;
334                 else {
335                         if (!list_empty(&sp->so_lru))
336                                 list_del_init(&sp->so_lru);
337                         atomic_inc(&sp->so_count);
338                         return sp;
339                 }
340         }
341         return NULL;
342 }
343
344 static struct nfs4_state_owner *
345 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
346 {
347         struct nfs_server *server = new->so_server;
348         struct rb_node **p = &server->state_owners.rb_node,
349                        *parent = NULL;
350         struct nfs4_state_owner *sp;
351         int err;
352
353         while (*p != NULL) {
354                 parent = *p;
355                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
356
357                 if (new->so_cred < sp->so_cred)
358                         p = &parent->rb_left;
359                 else if (new->so_cred > sp->so_cred)
360                         p = &parent->rb_right;
361                 else {
362                         if (!list_empty(&sp->so_lru))
363                                 list_del_init(&sp->so_lru);
364                         atomic_inc(&sp->so_count);
365                         return sp;
366                 }
367         }
368         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
369         if (err)
370                 return ERR_PTR(err);
371         rb_link_node(&new->so_server_node, parent, p);
372         rb_insert_color(&new->so_server_node, &server->state_owners);
373         return new;
374 }
375
376 static void
377 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
378 {
379         struct nfs_server *server = sp->so_server;
380
381         if (!RB_EMPTY_NODE(&sp->so_server_node))
382                 rb_erase(&sp->so_server_node, &server->state_owners);
383         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
384 }
385
386 static void
387 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
388 {
389         sc->flags = 0;
390         sc->counter = 0;
391         spin_lock_init(&sc->lock);
392         INIT_LIST_HEAD(&sc->list);
393         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
394 }
395
396 static void
397 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
398 {
399         rpc_destroy_wait_queue(&sc->wait);
400 }
401
402 /*
403  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
404  * create a new state_owner.
405  *
406  */
407 static struct nfs4_state_owner *
408 nfs4_alloc_state_owner(struct nfs_server *server,
409                 struct rpc_cred *cred,
410                 gfp_t gfp_flags)
411 {
412         struct nfs4_state_owner *sp;
413
414         sp = kzalloc(sizeof(*sp), gfp_flags);
415         if (!sp)
416                 return NULL;
417         sp->so_server = server;
418         sp->so_cred = get_rpccred(cred);
419         spin_lock_init(&sp->so_lock);
420         INIT_LIST_HEAD(&sp->so_states);
421         nfs4_init_seqid_counter(&sp->so_seqid);
422         atomic_set(&sp->so_count, 1);
423         INIT_LIST_HEAD(&sp->so_lru);
424         return sp;
425 }
426
427 static void
428 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
429 {
430         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
431                 struct nfs_server *server = sp->so_server;
432                 struct nfs_client *clp = server->nfs_client;
433
434                 spin_lock(&clp->cl_lock);
435                 rb_erase(&sp->so_server_node, &server->state_owners);
436                 RB_CLEAR_NODE(&sp->so_server_node);
437                 spin_unlock(&clp->cl_lock);
438         }
439 }
440
441 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
442 {
443         nfs4_destroy_seqid_counter(&sp->so_seqid);
444         put_rpccred(sp->so_cred);
445         kfree(sp);
446 }
447
448 static void nfs4_gc_state_owners(struct nfs_server *server)
449 {
450         struct nfs_client *clp = server->nfs_client;
451         struct nfs4_state_owner *sp, *tmp;
452         unsigned long time_min, time_max;
453         LIST_HEAD(doomed);
454
455         spin_lock(&clp->cl_lock);
456         time_max = jiffies;
457         time_min = (long)time_max - (long)clp->cl_lease_time;
458         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
459                 /* NB: LRU is sorted so that oldest is at the head */
460                 if (time_in_range(sp->so_expires, time_min, time_max))
461                         break;
462                 list_move(&sp->so_lru, &doomed);
463                 nfs4_remove_state_owner_locked(sp);
464         }
465         spin_unlock(&clp->cl_lock);
466
467         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
468                 list_del(&sp->so_lru);
469                 nfs4_free_state_owner(sp);
470         }
471 }
472
473 /**
474  * nfs4_get_state_owner - Look up a state owner given a credential
475  * @server: nfs_server to search
476  * @cred: RPC credential to match
477  *
478  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
479  */
480 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
481                                               struct rpc_cred *cred,
482                                               gfp_t gfp_flags)
483 {
484         struct nfs_client *clp = server->nfs_client;
485         struct nfs4_state_owner *sp, *new;
486
487         spin_lock(&clp->cl_lock);
488         sp = nfs4_find_state_owner_locked(server, cred);
489         spin_unlock(&clp->cl_lock);
490         if (sp != NULL)
491                 goto out;
492         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
493         if (new == NULL)
494                 goto out;
495         do {
496                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
497                         break;
498                 spin_lock(&clp->cl_lock);
499                 sp = nfs4_insert_state_owner_locked(new);
500                 spin_unlock(&clp->cl_lock);
501         } while (sp == ERR_PTR(-EAGAIN));
502         if (sp != new)
503                 nfs4_free_state_owner(new);
504 out:
505         nfs4_gc_state_owners(server);
506         return sp;
507 }
508
509 /**
510  * nfs4_put_state_owner - Release a nfs4_state_owner
511  * @sp: state owner data to release
512  */
513 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
514 {
515         struct nfs_server *server = sp->so_server;
516         struct nfs_client *clp = server->nfs_client;
517
518         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
519                 return;
520
521         if (!RB_EMPTY_NODE(&sp->so_server_node)) {
522                 sp->so_expires = jiffies;
523                 list_add_tail(&sp->so_lru, &server->state_owners_lru);
524                 spin_unlock(&clp->cl_lock);
525         } else {
526                 nfs4_remove_state_owner_locked(sp);
527                 spin_unlock(&clp->cl_lock);
528                 nfs4_free_state_owner(sp);
529         }
530 }
531
532 /**
533  * nfs4_purge_state_owners - Release all cached state owners
534  * @server: nfs_server with cached state owners to release
535  *
536  * Called at umount time.  Remaining state owners will be on
537  * the LRU with ref count of zero.
538  */
539 void nfs4_purge_state_owners(struct nfs_server *server)
540 {
541         struct nfs_client *clp = server->nfs_client;
542         struct nfs4_state_owner *sp, *tmp;
543         LIST_HEAD(doomed);
544
545         spin_lock(&clp->cl_lock);
546         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
547                 list_move(&sp->so_lru, &doomed);
548                 nfs4_remove_state_owner_locked(sp);
549         }
550         spin_unlock(&clp->cl_lock);
551
552         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
553                 list_del(&sp->so_lru);
554                 nfs4_free_state_owner(sp);
555         }
556 }
557
558 static struct nfs4_state *
559 nfs4_alloc_open_state(void)
560 {
561         struct nfs4_state *state;
562
563         state = kzalloc(sizeof(*state), GFP_NOFS);
564         if (!state)
565                 return NULL;
566         atomic_set(&state->count, 1);
567         INIT_LIST_HEAD(&state->lock_states);
568         spin_lock_init(&state->state_lock);
569         seqlock_init(&state->seqlock);
570         return state;
571 }
572
573 void
574 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
575 {
576         if (state->state == fmode)
577                 return;
578         /* NB! List reordering - see the reclaim code for why.  */
579         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
580                 if (fmode & FMODE_WRITE)
581                         list_move(&state->open_states, &state->owner->so_states);
582                 else
583                         list_move_tail(&state->open_states, &state->owner->so_states);
584         }
585         state->state = fmode;
586 }
587
588 static struct nfs4_state *
589 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
590 {
591         struct nfs_inode *nfsi = NFS_I(inode);
592         struct nfs4_state *state;
593
594         list_for_each_entry(state, &nfsi->open_states, inode_states) {
595                 if (state->owner != owner)
596                         continue;
597                 if (atomic_inc_not_zero(&state->count))
598                         return state;
599         }
600         return NULL;
601 }
602
603 static void
604 nfs4_free_open_state(struct nfs4_state *state)
605 {
606         kfree(state);
607 }
608
609 struct nfs4_state *
610 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
611 {
612         struct nfs4_state *state, *new;
613         struct nfs_inode *nfsi = NFS_I(inode);
614
615         spin_lock(&inode->i_lock);
616         state = __nfs4_find_state_byowner(inode, owner);
617         spin_unlock(&inode->i_lock);
618         if (state)
619                 goto out;
620         new = nfs4_alloc_open_state();
621         spin_lock(&owner->so_lock);
622         spin_lock(&inode->i_lock);
623         state = __nfs4_find_state_byowner(inode, owner);
624         if (state == NULL && new != NULL) {
625                 state = new;
626                 state->owner = owner;
627                 atomic_inc(&owner->so_count);
628                 list_add(&state->inode_states, &nfsi->open_states);
629                 ihold(inode);
630                 state->inode = inode;
631                 spin_unlock(&inode->i_lock);
632                 /* Note: The reclaim code dictates that we add stateless
633                  * and read-only stateids to the end of the list */
634                 list_add_tail(&state->open_states, &owner->so_states);
635                 spin_unlock(&owner->so_lock);
636         } else {
637                 spin_unlock(&inode->i_lock);
638                 spin_unlock(&owner->so_lock);
639                 if (new)
640                         nfs4_free_open_state(new);
641         }
642 out:
643         return state;
644 }
645
646 void nfs4_put_open_state(struct nfs4_state *state)
647 {
648         struct inode *inode = state->inode;
649         struct nfs4_state_owner *owner = state->owner;
650
651         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
652                 return;
653         spin_lock(&inode->i_lock);
654         list_del(&state->inode_states);
655         list_del(&state->open_states);
656         spin_unlock(&inode->i_lock);
657         spin_unlock(&owner->so_lock);
658         iput(inode);
659         nfs4_free_open_state(state);
660         nfs4_put_state_owner(owner);
661 }
662
663 /*
664  * Close the current file.
665  */
666 static void __nfs4_close(struct nfs4_state *state,
667                 fmode_t fmode, gfp_t gfp_mask, int wait)
668 {
669         struct nfs4_state_owner *owner = state->owner;
670         int call_close = 0;
671         fmode_t newstate;
672
673         atomic_inc(&owner->so_count);
674         /* Protect against nfs4_find_state() */
675         spin_lock(&owner->so_lock);
676         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
677                 case FMODE_READ:
678                         state->n_rdonly--;
679                         break;
680                 case FMODE_WRITE:
681                         state->n_wronly--;
682                         break;
683                 case FMODE_READ|FMODE_WRITE:
684                         state->n_rdwr--;
685         }
686         newstate = FMODE_READ|FMODE_WRITE;
687         if (state->n_rdwr == 0) {
688                 if (state->n_rdonly == 0) {
689                         newstate &= ~FMODE_READ;
690                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
691                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
692                 }
693                 if (state->n_wronly == 0) {
694                         newstate &= ~FMODE_WRITE;
695                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
696                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
697                 }
698                 if (newstate == 0)
699                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
700         }
701         nfs4_state_set_mode_locked(state, newstate);
702         spin_unlock(&owner->so_lock);
703
704         if (!call_close) {
705                 nfs4_put_open_state(state);
706                 nfs4_put_state_owner(owner);
707         } else {
708                 bool roc = pnfs_roc(state->inode);
709
710                 nfs4_do_close(state, gfp_mask, wait, roc);
711         }
712 }
713
714 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
715 {
716         __nfs4_close(state, fmode, GFP_NOFS, 0);
717 }
718
719 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
720 {
721         __nfs4_close(state, fmode, GFP_KERNEL, 1);
722 }
723
724 /*
725  * Search the state->lock_states for an existing lock_owner
726  * that is compatible with current->files
727  */
728 static struct nfs4_lock_state *
729 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
730 {
731         struct nfs4_lock_state *pos;
732         list_for_each_entry(pos, &state->lock_states, ls_locks) {
733                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
734                         continue;
735                 switch (pos->ls_owner.lo_type) {
736                 case NFS4_POSIX_LOCK_TYPE:
737                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
738                                 continue;
739                         break;
740                 case NFS4_FLOCK_LOCK_TYPE:
741                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
742                                 continue;
743                 }
744                 atomic_inc(&pos->ls_count);
745                 return pos;
746         }
747         return NULL;
748 }
749
750 /*
751  * Return a compatible lock_state. If no initialized lock_state structure
752  * exists, return an uninitialized one.
753  *
754  */
755 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
756 {
757         struct nfs4_lock_state *lsp;
758         struct nfs_server *server = state->owner->so_server;
759
760         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
761         if (lsp == NULL)
762                 return NULL;
763         nfs4_init_seqid_counter(&lsp->ls_seqid);
764         atomic_set(&lsp->ls_count, 1);
765         lsp->ls_state = state;
766         lsp->ls_owner.lo_type = type;
767         switch (lsp->ls_owner.lo_type) {
768         case NFS4_FLOCK_LOCK_TYPE:
769                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
770                 break;
771         case NFS4_POSIX_LOCK_TYPE:
772                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
773                 break;
774         default:
775                 goto out_free;
776         }
777         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
778         if (lsp->ls_seqid.owner_id < 0)
779                 goto out_free;
780         INIT_LIST_HEAD(&lsp->ls_locks);
781         return lsp;
782 out_free:
783         kfree(lsp);
784         return NULL;
785 }
786
787 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         nfs4_state_mark_reclaim_nograce(clp, state);
1110         nfs4_schedule_state_manager(clp);
1111 }
1112
1113 void nfs_inode_find_state_and_recover(struct inode *inode,
1114                 const nfs4_stateid *stateid)
1115 {
1116         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1117         struct nfs_inode *nfsi = NFS_I(inode);
1118         struct nfs_open_context *ctx;
1119         struct nfs4_state *state;
1120         bool found = false;
1121
1122         spin_lock(&inode->i_lock);
1123         list_for_each_entry(ctx, &nfsi->open_files, list) {
1124                 state = ctx->state;
1125                 if (state == NULL)
1126                         continue;
1127                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1128                         continue;
1129                 if (memcmp(state->stateid.data, stateid->data, sizeof(state->stateid.data)) != 0)
1130                         continue;
1131                 nfs4_state_mark_reclaim_nograce(clp, state);
1132                 found = true;
1133         }
1134         spin_unlock(&inode->i_lock);
1135         if (found)
1136                 nfs4_schedule_state_manager(clp);
1137 }
1138
1139
1140 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1141 {
1142         struct inode *inode = state->inode;
1143         struct nfs_inode *nfsi = NFS_I(inode);
1144         struct file_lock *fl;
1145         int status = 0;
1146
1147         if (inode->i_flock == NULL)
1148                 return 0;
1149
1150         /* Guard against delegation returns and new lock/unlock calls */
1151         down_write(&nfsi->rwsem);
1152         /* Protect inode->i_flock using the BKL */
1153         lock_flocks();
1154         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1155                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1156                         continue;
1157                 if (nfs_file_open_context(fl->fl_file)->state != state)
1158                         continue;
1159                 unlock_flocks();
1160                 status = ops->recover_lock(state, fl);
1161                 switch (status) {
1162                         case 0:
1163                                 break;
1164                         case -ESTALE:
1165                         case -NFS4ERR_ADMIN_REVOKED:
1166                         case -NFS4ERR_STALE_STATEID:
1167                         case -NFS4ERR_BAD_STATEID:
1168                         case -NFS4ERR_EXPIRED:
1169                         case -NFS4ERR_NO_GRACE:
1170                         case -NFS4ERR_STALE_CLIENTID:
1171                         case -NFS4ERR_BADSESSION:
1172                         case -NFS4ERR_BADSLOT:
1173                         case -NFS4ERR_BAD_HIGH_SLOT:
1174                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1175                                 goto out;
1176                         default:
1177                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1178                                         "Zeroing state\n", __func__, status);
1179                         case -ENOMEM:
1180                         case -NFS4ERR_DENIED:
1181                         case -NFS4ERR_RECLAIM_BAD:
1182                         case -NFS4ERR_RECLAIM_CONFLICT:
1183                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1184                                 status = 0;
1185                 }
1186                 lock_flocks();
1187         }
1188         unlock_flocks();
1189 out:
1190         up_write(&nfsi->rwsem);
1191         return status;
1192 }
1193
1194 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1195 {
1196         struct nfs4_state *state;
1197         struct nfs4_lock_state *lock;
1198         int status = 0;
1199
1200         /* Note: we rely on the sp->so_states list being ordered 
1201          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1202          * states first.
1203          * This is needed to ensure that the server won't give us any
1204          * read delegations that we have to return if, say, we are
1205          * recovering after a network partition or a reboot from a
1206          * server that doesn't support a grace period.
1207          */
1208 restart:
1209         spin_lock(&sp->so_lock);
1210         list_for_each_entry(state, &sp->so_states, open_states) {
1211                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1212                         continue;
1213                 if (state->state == 0)
1214                         continue;
1215                 atomic_inc(&state->count);
1216                 spin_unlock(&sp->so_lock);
1217                 status = ops->recover_open(sp, state);
1218                 if (status >= 0) {
1219                         status = nfs4_reclaim_locks(state, ops);
1220                         if (status >= 0) {
1221                                 spin_lock(&state->state_lock);
1222                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1223                                         if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
1224                                                 printk("NFS: %s: Lock reclaim "
1225                                                         "failed!\n", __func__);
1226                                 }
1227                                 spin_unlock(&state->state_lock);
1228                                 nfs4_put_open_state(state);
1229                                 goto restart;
1230                         }
1231                 }
1232                 switch (status) {
1233                         default:
1234                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1235                                         "Zeroing state\n", __func__, status);
1236                         case -ENOENT:
1237                         case -ENOMEM:
1238                         case -ESTALE:
1239                                 /*
1240                                  * Open state on this file cannot be recovered
1241                                  * All we can do is revert to using the zero stateid.
1242                                  */
1243                                 memset(state->stateid.data, 0,
1244                                         sizeof(state->stateid.data));
1245                                 /* Mark the file as being 'closed' */
1246                                 state->state = 0;
1247                                 break;
1248                         case -EKEYEXPIRED:
1249                                 /*
1250                                  * User RPCSEC_GSS context has expired.
1251                                  * We cannot recover this stateid now, so
1252                                  * skip it and allow recovery thread to
1253                                  * proceed.
1254                                  */
1255                                 break;
1256                         case -NFS4ERR_ADMIN_REVOKED:
1257                         case -NFS4ERR_STALE_STATEID:
1258                         case -NFS4ERR_BAD_STATEID:
1259                         case -NFS4ERR_RECLAIM_BAD:
1260                         case -NFS4ERR_RECLAIM_CONFLICT:
1261                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1262                                 break;
1263                         case -NFS4ERR_EXPIRED:
1264                         case -NFS4ERR_NO_GRACE:
1265                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1266                         case -NFS4ERR_STALE_CLIENTID:
1267                         case -NFS4ERR_BADSESSION:
1268                         case -NFS4ERR_BADSLOT:
1269                         case -NFS4ERR_BAD_HIGH_SLOT:
1270                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1271                                 goto out_err;
1272                 }
1273                 nfs4_put_open_state(state);
1274                 goto restart;
1275         }
1276         spin_unlock(&sp->so_lock);
1277         return 0;
1278 out_err:
1279         nfs4_put_open_state(state);
1280         return status;
1281 }
1282
1283 static void nfs4_clear_open_state(struct nfs4_state *state)
1284 {
1285         struct nfs4_lock_state *lock;
1286
1287         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1288         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1289         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1290         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1291         spin_lock(&state->state_lock);
1292         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1293                 lock->ls_seqid.flags = 0;
1294                 lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
1295         }
1296         spin_unlock(&state->state_lock);
1297 }
1298
1299 static void nfs4_reset_seqids(struct nfs_server *server,
1300         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1301 {
1302         struct nfs_client *clp = server->nfs_client;
1303         struct nfs4_state_owner *sp;
1304         struct rb_node *pos;
1305         struct nfs4_state *state;
1306
1307         spin_lock(&clp->cl_lock);
1308         for (pos = rb_first(&server->state_owners);
1309              pos != NULL;
1310              pos = rb_next(pos)) {
1311                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1312                 sp->so_seqid.flags = 0;
1313                 spin_lock(&sp->so_lock);
1314                 list_for_each_entry(state, &sp->so_states, open_states) {
1315                         if (mark_reclaim(clp, state))
1316                                 nfs4_clear_open_state(state);
1317                 }
1318                 spin_unlock(&sp->so_lock);
1319         }
1320         spin_unlock(&clp->cl_lock);
1321 }
1322
1323 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1324         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1325 {
1326         struct nfs_server *server;
1327
1328         rcu_read_lock();
1329         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1330                 nfs4_reset_seqids(server, mark_reclaim);
1331         rcu_read_unlock();
1332 }
1333
1334 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1335 {
1336         /* Mark all delegations for reclaim */
1337         nfs_delegation_mark_reclaim(clp);
1338         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1339 }
1340
1341 static void nfs4_reclaim_complete(struct nfs_client *clp,
1342                                  const struct nfs4_state_recovery_ops *ops)
1343 {
1344         /* Notify the server we're done reclaiming our state */
1345         if (ops->reclaim_complete)
1346                 (void)ops->reclaim_complete(clp);
1347 }
1348
1349 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1350 {
1351         struct nfs_client *clp = server->nfs_client;
1352         struct nfs4_state_owner *sp;
1353         struct rb_node *pos;
1354         struct nfs4_state *state;
1355
1356         spin_lock(&clp->cl_lock);
1357         for (pos = rb_first(&server->state_owners);
1358              pos != NULL;
1359              pos = rb_next(pos)) {
1360                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1361                 spin_lock(&sp->so_lock);
1362                 list_for_each_entry(state, &sp->so_states, open_states) {
1363                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1364                                                 &state->flags))
1365                                 continue;
1366                         nfs4_state_mark_reclaim_nograce(clp, state);
1367                 }
1368                 spin_unlock(&sp->so_lock);
1369         }
1370         spin_unlock(&clp->cl_lock);
1371 }
1372
1373 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1374 {
1375         struct nfs_server *server;
1376
1377         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1378                 return 0;
1379
1380         rcu_read_lock();
1381         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1382                 nfs4_clear_reclaim_server(server);
1383         rcu_read_unlock();
1384
1385         nfs_delegation_reap_unclaimed(clp);
1386         return 1;
1387 }
1388
1389 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1390 {
1391         if (!nfs4_state_clear_reclaim_reboot(clp))
1392                 return;
1393         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1394 }
1395
1396 static void nfs_delegation_clear_all(struct nfs_client *clp)
1397 {
1398         nfs_delegation_mark_reclaim(clp);
1399         nfs_delegation_reap_unclaimed(clp);
1400 }
1401
1402 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1403 {
1404         nfs_delegation_clear_all(clp);
1405         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1406 }
1407
1408 static void nfs4_warn_keyexpired(const char *s)
1409 {
1410         printk_ratelimited(KERN_WARNING "Error: state manager"
1411                         " encountered RPCSEC_GSS session"
1412                         " expired against NFSv4 server %s.\n",
1413                         s);
1414 }
1415
1416 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1417 {
1418         switch (error) {
1419                 case 0:
1420                         break;
1421                 case -NFS4ERR_CB_PATH_DOWN:
1422                         nfs_handle_cb_pathdown(clp);
1423                         break;
1424                 case -NFS4ERR_NO_GRACE:
1425                         nfs4_state_end_reclaim_reboot(clp);
1426                         break;
1427                 case -NFS4ERR_STALE_CLIENTID:
1428                 case -NFS4ERR_LEASE_MOVED:
1429                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1430                         nfs4_state_clear_reclaim_reboot(clp);
1431                         nfs4_state_start_reclaim_reboot(clp);
1432                         break;
1433                 case -NFS4ERR_EXPIRED:
1434                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1435                         nfs4_state_start_reclaim_nograce(clp);
1436                         break;
1437                 case -NFS4ERR_BADSESSION:
1438                 case -NFS4ERR_BADSLOT:
1439                 case -NFS4ERR_BAD_HIGH_SLOT:
1440                 case -NFS4ERR_DEADSESSION:
1441                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1442                 case -NFS4ERR_SEQ_FALSE_RETRY:
1443                 case -NFS4ERR_SEQ_MISORDERED:
1444                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1445                         /* Zero session reset errors */
1446                         break;
1447                 case -EKEYEXPIRED:
1448                         /* Nothing we can do */
1449                         nfs4_warn_keyexpired(clp->cl_hostname);
1450                         break;
1451                 default:
1452                         return error;
1453         }
1454         return 0;
1455 }
1456
1457 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1458 {
1459         struct nfs4_state_owner *sp;
1460         struct nfs_server *server;
1461         struct rb_node *pos;
1462         int status = 0;
1463
1464 restart:
1465         rcu_read_lock();
1466         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1467                 nfs4_purge_state_owners(server);
1468                 spin_lock(&clp->cl_lock);
1469                 for (pos = rb_first(&server->state_owners);
1470                      pos != NULL;
1471                      pos = rb_next(pos)) {
1472                         sp = rb_entry(pos,
1473                                 struct nfs4_state_owner, so_server_node);
1474                         if (!test_and_clear_bit(ops->owner_flag_bit,
1475                                                         &sp->so_flags))
1476                                 continue;
1477                         atomic_inc(&sp->so_count);
1478                         spin_unlock(&clp->cl_lock);
1479                         rcu_read_unlock();
1480
1481                         status = nfs4_reclaim_open_state(sp, ops);
1482                         if (status < 0) {
1483                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1484                                 nfs4_put_state_owner(sp);
1485                                 return nfs4_recovery_handle_error(clp, status);
1486                         }
1487
1488                         nfs4_put_state_owner(sp);
1489                         goto restart;
1490                 }
1491                 spin_unlock(&clp->cl_lock);
1492         }
1493         rcu_read_unlock();
1494         return status;
1495 }
1496
1497 static int nfs4_check_lease(struct nfs_client *clp)
1498 {
1499         struct rpc_cred *cred;
1500         const struct nfs4_state_maintenance_ops *ops =
1501                 clp->cl_mvops->state_renewal_ops;
1502         int status;
1503
1504         /* Is the client already known to have an expired lease? */
1505         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1506                 return 0;
1507         spin_lock(&clp->cl_lock);
1508         cred = ops->get_state_renewal_cred_locked(clp);
1509         spin_unlock(&clp->cl_lock);
1510         if (cred == NULL) {
1511                 cred = nfs4_get_setclientid_cred(clp);
1512                 status = -ENOKEY;
1513                 if (cred == NULL)
1514                         goto out;
1515         }
1516         status = ops->renew_lease(clp, cred);
1517         put_rpccred(cred);
1518 out:
1519         return nfs4_recovery_handle_error(clp, status);
1520 }
1521
1522 static int nfs4_reclaim_lease(struct nfs_client *clp)
1523 {
1524         struct rpc_cred *cred;
1525         const struct nfs4_state_recovery_ops *ops =
1526                 clp->cl_mvops->reboot_recovery_ops;
1527         int status = -ENOENT;
1528
1529         cred = ops->get_clid_cred(clp);
1530         if (cred != NULL) {
1531                 status = ops->establish_clid(clp, cred);
1532                 put_rpccred(cred);
1533                 /* Handle case where the user hasn't set up machine creds */
1534                 if (status == -EACCES && cred == clp->cl_machine_cred) {
1535                         nfs4_clear_machine_cred(clp);
1536                         status = -EAGAIN;
1537                 }
1538                 if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1539                         status = -EPROTONOSUPPORT;
1540         }
1541         return status;
1542 }
1543
1544 #ifdef CONFIG_NFS_V4_1
1545 void nfs4_schedule_session_recovery(struct nfs4_session *session)
1546 {
1547         struct nfs_client *clp = session->clp;
1548
1549         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1550         nfs4_schedule_lease_recovery(clp);
1551 }
1552 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1553
1554 void nfs41_handle_recall_slot(struct nfs_client *clp)
1555 {
1556         set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1557         nfs4_schedule_state_manager(clp);
1558 }
1559
1560 static void nfs4_reset_all_state(struct nfs_client *clp)
1561 {
1562         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1563                 clp->cl_boot_time = CURRENT_TIME;
1564                 nfs4_state_start_reclaim_nograce(clp);
1565                 nfs4_schedule_state_manager(clp);
1566         }
1567 }
1568
1569 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1570 {
1571         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1572                 nfs4_state_start_reclaim_reboot(clp);
1573                 nfs4_schedule_state_manager(clp);
1574         }
1575 }
1576
1577 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1578 {
1579         /* Temporary */
1580         nfs4_reset_all_state(clp);
1581 }
1582
1583 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1584 {
1585         /* This will need to handle layouts too */
1586         nfs_expire_all_delegations(clp);
1587 }
1588
1589 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
1590 {
1591         nfs_expire_all_delegations(clp);
1592         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
1593                 nfs4_schedule_state_manager(clp);
1594 }
1595
1596 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
1597 {
1598         if (!flags)
1599                 return;
1600         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
1601                 nfs41_handle_server_reboot(clp);
1602         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
1603                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
1604                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
1605                             SEQ4_STATUS_LEASE_MOVED))
1606                 nfs41_handle_state_revoked(clp);
1607         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
1608                 nfs41_handle_recallable_state_revoked(clp);
1609         if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
1610                             SEQ4_STATUS_BACKCHANNEL_FAULT |
1611                             SEQ4_STATUS_CB_PATH_DOWN_SESSION))
1612                 nfs41_handle_cb_path_down(clp);
1613 }
1614
1615 static int nfs4_reset_session(struct nfs_client *clp)
1616 {
1617         int status;
1618
1619         nfs4_begin_drain_session(clp);
1620         status = nfs4_proc_destroy_session(clp->cl_session);
1621         if (status && status != -NFS4ERR_BADSESSION &&
1622             status != -NFS4ERR_DEADSESSION) {
1623                 status = nfs4_recovery_handle_error(clp, status);
1624                 goto out;
1625         }
1626
1627         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1628         status = nfs4_proc_create_session(clp);
1629         if (status) {
1630                 status = nfs4_recovery_handle_error(clp, status);
1631                 goto out;
1632         }
1633         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1634         /* create_session negotiated new slot table */
1635         clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
1636
1637          /* Let the state manager reestablish state */
1638         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1639                 nfs41_setup_state_renewal(clp);
1640 out:
1641         return status;
1642 }
1643
1644 static int nfs4_recall_slot(struct nfs_client *clp)
1645 {
1646         struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
1647         struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
1648         struct nfs4_slot *new, *old;
1649         int i;
1650
1651         nfs4_begin_drain_session(clp);
1652         new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
1653                       GFP_NOFS);
1654         if (!new)
1655                 return -ENOMEM;
1656
1657         spin_lock(&fc_tbl->slot_tbl_lock);
1658         for (i = 0; i < fc_tbl->target_max_slots; i++)
1659                 new[i].seq_nr = fc_tbl->slots[i].seq_nr;
1660         old = fc_tbl->slots;
1661         fc_tbl->slots = new;
1662         fc_tbl->max_slots = fc_tbl->target_max_slots;
1663         fc_tbl->target_max_slots = 0;
1664         fc_attrs->max_reqs = fc_tbl->max_slots;
1665         spin_unlock(&fc_tbl->slot_tbl_lock);
1666
1667         kfree(old);
1668         nfs4_end_drain_session(clp);
1669         return 0;
1670 }
1671
1672 #else /* CONFIG_NFS_V4_1 */
1673 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1674 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
1675 static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
1676 #endif /* CONFIG_NFS_V4_1 */
1677
1678 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1679  * on EXCHANGE_ID for v4.1
1680  */
1681 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1682 {
1683         switch (status) {
1684         case -NFS4ERR_CLID_INUSE:
1685         case -NFS4ERR_STALE_CLIENTID:
1686                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1687                 break;
1688         case -NFS4ERR_DELAY:
1689         case -ETIMEDOUT:
1690         case -EAGAIN:
1691                 ssleep(1);
1692                 break;
1693
1694         case -EKEYEXPIRED:
1695                 nfs4_warn_keyexpired(clp->cl_hostname);
1696         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1697                                  * in nfs4_exchange_id */
1698         default:
1699                 return;
1700         }
1701         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1702 }
1703
1704 static void nfs4_state_manager(struct nfs_client *clp)
1705 {
1706         int status = 0;
1707
1708         /* Ensure exclusive access to NFSv4 state */
1709         do {
1710                 if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1711                         /* We're going to have to re-establish a clientid */
1712                         status = nfs4_reclaim_lease(clp);
1713                         if (status) {
1714                                 nfs4_set_lease_expired(clp, status);
1715                                 if (test_bit(NFS4CLNT_LEASE_EXPIRED,
1716                                                         &clp->cl_state))
1717                                         continue;
1718                                 if (clp->cl_cons_state ==
1719                                                         NFS_CS_SESSION_INITING)
1720                                         nfs_mark_client_ready(clp, status);
1721                                 goto out_error;
1722                         }
1723                         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1724
1725                         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH,
1726                                                &clp->cl_state))
1727                                 nfs4_state_start_reclaim_nograce(clp);
1728                         else
1729                                 set_bit(NFS4CLNT_RECLAIM_REBOOT,
1730                                         &clp->cl_state);
1731
1732                         pnfs_destroy_all_layouts(clp);
1733                 }
1734
1735                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1736                         status = nfs4_check_lease(clp);
1737                         if (status < 0)
1738                                 goto out_error;
1739                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1740                                 continue;
1741                 }
1742
1743                 /* Initialize or reset the session */
1744                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
1745                    && nfs4_has_session(clp)) {
1746                         status = nfs4_reset_session(clp);
1747                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1748                                 continue;
1749                         if (status < 0)
1750                                 goto out_error;
1751                 }
1752
1753                 /* First recover reboot state... */
1754                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1755                         status = nfs4_do_reclaim(clp,
1756                                 clp->cl_mvops->reboot_recovery_ops);
1757                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1758                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
1759                                 continue;
1760                         nfs4_state_end_reclaim_reboot(clp);
1761                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1762                                 continue;
1763                         if (status < 0)
1764                                 goto out_error;
1765                 }
1766
1767                 /* Now recover expired state... */
1768                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1769                         status = nfs4_do_reclaim(clp,
1770                                 clp->cl_mvops->nograce_recovery_ops);
1771                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
1772                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
1773                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1774                                 continue;
1775                         if (status < 0)
1776                                 goto out_error;
1777                 }
1778
1779                 nfs4_end_drain_session(clp);
1780                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1781                         nfs_client_return_marked_delegations(clp);
1782                         continue;
1783                 }
1784                 /* Recall session slots */
1785                 if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
1786                    && nfs4_has_session(clp)) {
1787                         status = nfs4_recall_slot(clp);
1788                         if (status < 0)
1789                                 goto out_error;
1790                         continue;
1791                 }
1792
1793
1794                 nfs4_clear_state_manager_bit(clp);
1795                 /* Did we race with an attempt to give us more work? */
1796                 if (clp->cl_state == 0)
1797                         break;
1798                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1799                         break;
1800         } while (atomic_read(&clp->cl_count) > 1);
1801         return;
1802 out_error:
1803         printk(KERN_WARNING "NFS: state manager failed on NFSv4 server %s"
1804                         " with error %d\n", clp->cl_hostname, -status);
1805         nfs4_end_drain_session(clp);
1806         nfs4_clear_state_manager_bit(clp);
1807 }
1808
1809 static int nfs4_run_state_manager(void *ptr)
1810 {
1811         struct nfs_client *clp = ptr;
1812
1813         allow_signal(SIGKILL);
1814         nfs4_state_manager(clp);
1815         nfs_put_client(clp);
1816         module_put_and_exit(0);
1817         return 0;
1818 }
1819
1820 /*
1821  * Local variables:
1822  *  c-basic-offset: 8
1823  * End:
1824  */