Merge remote-tracking branch 'asoc/topic/adau1701' into asoc-next
[platform/adaptation/renesas_rcar/renesas_kernel.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 <linux/sunrpc/clnt.h>
55
56 #include "nfs4_fs.h"
57 #include "callback.h"
58 #include "delegation.h"
59 #include "internal.h"
60 #include "nfs4session.h"
61 #include "pnfs.h"
62 #include "netns.h"
63
64 #define NFSDBG_FACILITY         NFSDBG_STATE
65
66 #define OPENOWNER_POOL_SIZE     8
67
68 const nfs4_stateid zero_stateid;
69 static DEFINE_MUTEX(nfs_clid_init_mutex);
70
71 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
72 {
73         struct nfs4_setclientid_res clid = {
74                 .clientid = clp->cl_clientid,
75                 .confirm = clp->cl_confirm,
76         };
77         unsigned short port;
78         int status;
79         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
80
81         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
82                 goto do_confirm;
83         port = nn->nfs_callback_tcpport;
84         if (clp->cl_addr.ss_family == AF_INET6)
85                 port = nn->nfs_callback_tcpport6;
86
87         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
88         if (status != 0)
89                 goto out;
90         clp->cl_clientid = clid.clientid;
91         clp->cl_confirm = clid.confirm;
92         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
93 do_confirm:
94         status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
95         if (status != 0)
96                 goto out;
97         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
98         nfs4_schedule_state_renewal(clp);
99 out:
100         return status;
101 }
102
103 /**
104  * nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
105  *
106  * @clp: nfs_client under test
107  * @result: OUT: found nfs_client, or clp
108  * @cred: credential to use for trunking test
109  *
110  * Returns zero, a negative errno, or a negative NFS4ERR status.
111  * If zero is returned, an nfs_client pointer is planted in
112  * "result".
113  *
114  * Note: The returned client may not yet be marked ready.
115  */
116 int nfs40_discover_server_trunking(struct nfs_client *clp,
117                                    struct nfs_client **result,
118                                    struct rpc_cred *cred)
119 {
120         struct nfs4_setclientid_res clid = {
121                 .clientid = clp->cl_clientid,
122                 .confirm = clp->cl_confirm,
123         };
124         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
125         unsigned short port;
126         int status;
127
128         port = nn->nfs_callback_tcpport;
129         if (clp->cl_addr.ss_family == AF_INET6)
130                 port = nn->nfs_callback_tcpport6;
131
132         status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
133         if (status != 0)
134                 goto out;
135         clp->cl_clientid = clid.clientid;
136         clp->cl_confirm = clid.confirm;
137
138         status = nfs40_walk_client_list(clp, result, cred);
139         if (status == 0) {
140                 /* Sustain the lease, even if it's empty.  If the clientid4
141                  * goes stale it's of no use for trunking discovery. */
142                 nfs4_schedule_state_renewal(*result);
143         }
144 out:
145         return status;
146 }
147
148 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
149 {
150         struct rpc_cred *cred = NULL;
151
152         if (clp->cl_machine_cred != NULL)
153                 cred = get_rpccred(clp->cl_machine_cred);
154         return cred;
155 }
156
157 static struct rpc_cred *
158 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
159 {
160         struct rpc_cred *cred = NULL;
161         struct nfs4_state_owner *sp;
162         struct rb_node *pos;
163
164         for (pos = rb_first(&server->state_owners);
165              pos != NULL;
166              pos = rb_next(pos)) {
167                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
168                 if (list_empty(&sp->so_states))
169                         continue;
170                 cred = get_rpccred(sp->so_cred);
171                 break;
172         }
173         return cred;
174 }
175
176 /**
177  * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
178  * @clp: client state handle
179  *
180  * Returns an rpc_cred with reference count bumped, or NULL.
181  * Caller must hold clp->cl_lock.
182  */
183 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
184 {
185         struct rpc_cred *cred = NULL;
186         struct nfs_server *server;
187
188         /* Use machine credentials if available */
189         cred = nfs4_get_machine_cred_locked(clp);
190         if (cred != NULL)
191                 goto out;
192
193         rcu_read_lock();
194         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
195                 cred = nfs4_get_renew_cred_server_locked(server);
196                 if (cred != NULL)
197                         break;
198         }
199         rcu_read_unlock();
200
201 out:
202         return cred;
203 }
204
205 #if defined(CONFIG_NFS_V4_1)
206
207 static int nfs41_setup_state_renewal(struct nfs_client *clp)
208 {
209         int status;
210         struct nfs_fsinfo fsinfo;
211
212         if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
213                 nfs4_schedule_state_renewal(clp);
214                 return 0;
215         }
216
217         status = nfs4_proc_get_lease_time(clp, &fsinfo);
218         if (status == 0) {
219                 /* Update lease time and schedule renewal */
220                 spin_lock(&clp->cl_lock);
221                 clp->cl_lease_time = fsinfo.lease_time * HZ;
222                 clp->cl_last_renewal = jiffies;
223                 spin_unlock(&clp->cl_lock);
224
225                 nfs4_schedule_state_renewal(clp);
226         }
227
228         return status;
229 }
230
231 /*
232  * Back channel returns NFS4ERR_DELAY for new requests when
233  * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
234  * is ended.
235  */
236 static void nfs4_end_drain_session(struct nfs_client *clp)
237 {
238         struct nfs4_session *ses = clp->cl_session;
239         struct nfs4_slot_table *tbl;
240
241         if (ses == NULL)
242                 return;
243         tbl = &ses->fc_slot_table;
244         if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
245                 spin_lock(&tbl->slot_tbl_lock);
246                 nfs41_wake_slot_table(tbl);
247                 spin_unlock(&tbl->slot_tbl_lock);
248         }
249 }
250
251 /*
252  * Signal state manager thread if session fore channel is drained
253  */
254 void nfs4_slot_tbl_drain_complete(struct nfs4_slot_table *tbl)
255 {
256         if (nfs4_slot_tbl_draining(tbl))
257                 complete(&tbl->complete);
258 }
259
260 static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
261 {
262         set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
263         spin_lock(&tbl->slot_tbl_lock);
264         if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
265                 INIT_COMPLETION(tbl->complete);
266                 spin_unlock(&tbl->slot_tbl_lock);
267                 return wait_for_completion_interruptible(&tbl->complete);
268         }
269         spin_unlock(&tbl->slot_tbl_lock);
270         return 0;
271 }
272
273 static int nfs4_begin_drain_session(struct nfs_client *clp)
274 {
275         struct nfs4_session *ses = clp->cl_session;
276         int ret = 0;
277
278         /* back channel */
279         ret = nfs4_drain_slot_tbl(&ses->bc_slot_table);
280         if (ret)
281                 return ret;
282         /* fore channel */
283         return nfs4_drain_slot_tbl(&ses->fc_slot_table);
284 }
285
286 static void nfs41_finish_session_reset(struct nfs_client *clp)
287 {
288         clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
289         clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
290         /* create_session negotiated new slot table */
291         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
292         nfs41_setup_state_renewal(clp);
293 }
294
295 int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
296 {
297         int status;
298
299         if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
300                 goto do_confirm;
301         nfs4_begin_drain_session(clp);
302         status = nfs4_proc_exchange_id(clp, cred);
303         if (status != 0)
304                 goto out;
305         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
306 do_confirm:
307         status = nfs4_proc_create_session(clp, cred);
308         if (status != 0)
309                 goto out;
310         nfs41_finish_session_reset(clp);
311         nfs_mark_client_ready(clp, NFS_CS_READY);
312 out:
313         return status;
314 }
315
316 /**
317  * nfs41_discover_server_trunking - Detect server IP address trunking (mv1)
318  *
319  * @clp: nfs_client under test
320  * @result: OUT: found nfs_client, or clp
321  * @cred: credential to use for trunking test
322  *
323  * Returns NFS4_OK, a negative errno, or a negative NFS4ERR status.
324  * If NFS4_OK is returned, an nfs_client pointer is planted in
325  * "result".
326  *
327  * Note: The returned client may not yet be marked ready.
328  */
329 int nfs41_discover_server_trunking(struct nfs_client *clp,
330                                    struct nfs_client **result,
331                                    struct rpc_cred *cred)
332 {
333         int status;
334
335         status = nfs4_proc_exchange_id(clp, cred);
336         if (status != NFS4_OK)
337                 return status;
338         set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
339
340         return nfs41_walk_client_list(clp, result, cred);
341 }
342
343 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
344 {
345         struct rpc_cred *cred;
346
347         spin_lock(&clp->cl_lock);
348         cred = nfs4_get_machine_cred_locked(clp);
349         spin_unlock(&clp->cl_lock);
350         return cred;
351 }
352
353 #endif /* CONFIG_NFS_V4_1 */
354
355 static struct rpc_cred *
356 nfs4_get_setclientid_cred_server(struct nfs_server *server)
357 {
358         struct nfs_client *clp = server->nfs_client;
359         struct rpc_cred *cred = NULL;
360         struct nfs4_state_owner *sp;
361         struct rb_node *pos;
362
363         spin_lock(&clp->cl_lock);
364         pos = rb_first(&server->state_owners);
365         if (pos != NULL) {
366                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
367                 cred = get_rpccred(sp->so_cred);
368         }
369         spin_unlock(&clp->cl_lock);
370         return cred;
371 }
372
373 /**
374  * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
375  * @clp: client state handle
376  *
377  * Returns an rpc_cred with reference count bumped, or NULL.
378  */
379 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
380 {
381         struct nfs_server *server;
382         struct rpc_cred *cred;
383
384         spin_lock(&clp->cl_lock);
385         cred = nfs4_get_machine_cred_locked(clp);
386         spin_unlock(&clp->cl_lock);
387         if (cred != NULL)
388                 goto out;
389
390         rcu_read_lock();
391         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
392                 cred = nfs4_get_setclientid_cred_server(server);
393                 if (cred != NULL)
394                         break;
395         }
396         rcu_read_unlock();
397
398 out:
399         return cred;
400 }
401
402 static struct nfs4_state_owner *
403 nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
404 {
405         struct rb_node **p = &server->state_owners.rb_node,
406                        *parent = NULL;
407         struct nfs4_state_owner *sp;
408
409         while (*p != NULL) {
410                 parent = *p;
411                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
412
413                 if (cred < sp->so_cred)
414                         p = &parent->rb_left;
415                 else if (cred > sp->so_cred)
416                         p = &parent->rb_right;
417                 else {
418                         if (!list_empty(&sp->so_lru))
419                                 list_del_init(&sp->so_lru);
420                         atomic_inc(&sp->so_count);
421                         return sp;
422                 }
423         }
424         return NULL;
425 }
426
427 static struct nfs4_state_owner *
428 nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
429 {
430         struct nfs_server *server = new->so_server;
431         struct rb_node **p = &server->state_owners.rb_node,
432                        *parent = NULL;
433         struct nfs4_state_owner *sp;
434         int err;
435
436         while (*p != NULL) {
437                 parent = *p;
438                 sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
439
440                 if (new->so_cred < sp->so_cred)
441                         p = &parent->rb_left;
442                 else if (new->so_cred > sp->so_cred)
443                         p = &parent->rb_right;
444                 else {
445                         if (!list_empty(&sp->so_lru))
446                                 list_del_init(&sp->so_lru);
447                         atomic_inc(&sp->so_count);
448                         return sp;
449                 }
450         }
451         err = ida_get_new(&server->openowner_id, &new->so_seqid.owner_id);
452         if (err)
453                 return ERR_PTR(err);
454         rb_link_node(&new->so_server_node, parent, p);
455         rb_insert_color(&new->so_server_node, &server->state_owners);
456         return new;
457 }
458
459 static void
460 nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
461 {
462         struct nfs_server *server = sp->so_server;
463
464         if (!RB_EMPTY_NODE(&sp->so_server_node))
465                 rb_erase(&sp->so_server_node, &server->state_owners);
466         ida_remove(&server->openowner_id, sp->so_seqid.owner_id);
467 }
468
469 static void
470 nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
471 {
472         sc->create_time = ktime_get();
473         sc->flags = 0;
474         sc->counter = 0;
475         spin_lock_init(&sc->lock);
476         INIT_LIST_HEAD(&sc->list);
477         rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
478 }
479
480 static void
481 nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
482 {
483         rpc_destroy_wait_queue(&sc->wait);
484 }
485
486 /*
487  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
488  * create a new state_owner.
489  *
490  */
491 static struct nfs4_state_owner *
492 nfs4_alloc_state_owner(struct nfs_server *server,
493                 struct rpc_cred *cred,
494                 gfp_t gfp_flags)
495 {
496         struct nfs4_state_owner *sp;
497
498         sp = kzalloc(sizeof(*sp), gfp_flags);
499         if (!sp)
500                 return NULL;
501         sp->so_server = server;
502         sp->so_cred = get_rpccred(cred);
503         spin_lock_init(&sp->so_lock);
504         INIT_LIST_HEAD(&sp->so_states);
505         nfs4_init_seqid_counter(&sp->so_seqid);
506         atomic_set(&sp->so_count, 1);
507         INIT_LIST_HEAD(&sp->so_lru);
508         seqcount_init(&sp->so_reclaim_seqcount);
509         mutex_init(&sp->so_delegreturn_mutex);
510         return sp;
511 }
512
513 static void
514 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
515 {
516         struct rb_node *rb_node = &sp->so_server_node;
517
518         if (!RB_EMPTY_NODE(rb_node)) {
519                 struct nfs_server *server = sp->so_server;
520                 struct nfs_client *clp = server->nfs_client;
521
522                 spin_lock(&clp->cl_lock);
523                 if (!RB_EMPTY_NODE(rb_node)) {
524                         rb_erase(rb_node, &server->state_owners);
525                         RB_CLEAR_NODE(rb_node);
526                 }
527                 spin_unlock(&clp->cl_lock);
528         }
529 }
530
531 static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
532 {
533         nfs4_destroy_seqid_counter(&sp->so_seqid);
534         put_rpccred(sp->so_cred);
535         kfree(sp);
536 }
537
538 static void nfs4_gc_state_owners(struct nfs_server *server)
539 {
540         struct nfs_client *clp = server->nfs_client;
541         struct nfs4_state_owner *sp, *tmp;
542         unsigned long time_min, time_max;
543         LIST_HEAD(doomed);
544
545         spin_lock(&clp->cl_lock);
546         time_max = jiffies;
547         time_min = (long)time_max - (long)clp->cl_lease_time;
548         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
549                 /* NB: LRU is sorted so that oldest is at the head */
550                 if (time_in_range(sp->so_expires, time_min, time_max))
551                         break;
552                 list_move(&sp->so_lru, &doomed);
553                 nfs4_remove_state_owner_locked(sp);
554         }
555         spin_unlock(&clp->cl_lock);
556
557         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
558                 list_del(&sp->so_lru);
559                 nfs4_free_state_owner(sp);
560         }
561 }
562
563 /**
564  * nfs4_get_state_owner - Look up a state owner given a credential
565  * @server: nfs_server to search
566  * @cred: RPC credential to match
567  *
568  * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
569  */
570 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
571                                               struct rpc_cred *cred,
572                                               gfp_t gfp_flags)
573 {
574         struct nfs_client *clp = server->nfs_client;
575         struct nfs4_state_owner *sp, *new;
576
577         spin_lock(&clp->cl_lock);
578         sp = nfs4_find_state_owner_locked(server, cred);
579         spin_unlock(&clp->cl_lock);
580         if (sp != NULL)
581                 goto out;
582         new = nfs4_alloc_state_owner(server, cred, gfp_flags);
583         if (new == NULL)
584                 goto out;
585         do {
586                 if (ida_pre_get(&server->openowner_id, gfp_flags) == 0)
587                         break;
588                 spin_lock(&clp->cl_lock);
589                 sp = nfs4_insert_state_owner_locked(new);
590                 spin_unlock(&clp->cl_lock);
591         } while (sp == ERR_PTR(-EAGAIN));
592         if (sp != new)
593                 nfs4_free_state_owner(new);
594 out:
595         nfs4_gc_state_owners(server);
596         return sp;
597 }
598
599 /**
600  * nfs4_put_state_owner - Release a nfs4_state_owner
601  * @sp: state owner data to release
602  *
603  * Note that we keep released state owners on an LRU
604  * list.
605  * This caches valid state owners so that they can be
606  * reused, to avoid the OPEN_CONFIRM on minor version 0.
607  * It also pins the uniquifier of dropped state owners for
608  * a while, to ensure that those state owner names are
609  * never reused.
610  */
611 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
612 {
613         struct nfs_server *server = sp->so_server;
614         struct nfs_client *clp = server->nfs_client;
615
616         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
617                 return;
618
619         sp->so_expires = jiffies;
620         list_add_tail(&sp->so_lru, &server->state_owners_lru);
621         spin_unlock(&clp->cl_lock);
622 }
623
624 /**
625  * nfs4_purge_state_owners - Release all cached state owners
626  * @server: nfs_server with cached state owners to release
627  *
628  * Called at umount time.  Remaining state owners will be on
629  * the LRU with ref count of zero.
630  */
631 void nfs4_purge_state_owners(struct nfs_server *server)
632 {
633         struct nfs_client *clp = server->nfs_client;
634         struct nfs4_state_owner *sp, *tmp;
635         LIST_HEAD(doomed);
636
637         spin_lock(&clp->cl_lock);
638         list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
639                 list_move(&sp->so_lru, &doomed);
640                 nfs4_remove_state_owner_locked(sp);
641         }
642         spin_unlock(&clp->cl_lock);
643
644         list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
645                 list_del(&sp->so_lru);
646                 nfs4_free_state_owner(sp);
647         }
648 }
649
650 static struct nfs4_state *
651 nfs4_alloc_open_state(void)
652 {
653         struct nfs4_state *state;
654
655         state = kzalloc(sizeof(*state), GFP_NOFS);
656         if (!state)
657                 return NULL;
658         atomic_set(&state->count, 1);
659         INIT_LIST_HEAD(&state->lock_states);
660         spin_lock_init(&state->state_lock);
661         seqlock_init(&state->seqlock);
662         return state;
663 }
664
665 void
666 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
667 {
668         if (state->state == fmode)
669                 return;
670         /* NB! List reordering - see the reclaim code for why.  */
671         if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
672                 if (fmode & FMODE_WRITE)
673                         list_move(&state->open_states, &state->owner->so_states);
674                 else
675                         list_move_tail(&state->open_states, &state->owner->so_states);
676         }
677         state->state = fmode;
678 }
679
680 static struct nfs4_state *
681 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
682 {
683         struct nfs_inode *nfsi = NFS_I(inode);
684         struct nfs4_state *state;
685
686         list_for_each_entry(state, &nfsi->open_states, inode_states) {
687                 if (state->owner != owner)
688                         continue;
689                 if (!nfs4_valid_open_stateid(state))
690                         continue;
691                 if (atomic_inc_not_zero(&state->count))
692                         return state;
693         }
694         return NULL;
695 }
696
697 static void
698 nfs4_free_open_state(struct nfs4_state *state)
699 {
700         kfree(state);
701 }
702
703 struct nfs4_state *
704 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
705 {
706         struct nfs4_state *state, *new;
707         struct nfs_inode *nfsi = NFS_I(inode);
708
709         spin_lock(&inode->i_lock);
710         state = __nfs4_find_state_byowner(inode, owner);
711         spin_unlock(&inode->i_lock);
712         if (state)
713                 goto out;
714         new = nfs4_alloc_open_state();
715         spin_lock(&owner->so_lock);
716         spin_lock(&inode->i_lock);
717         state = __nfs4_find_state_byowner(inode, owner);
718         if (state == NULL && new != NULL) {
719                 state = new;
720                 state->owner = owner;
721                 atomic_inc(&owner->so_count);
722                 list_add(&state->inode_states, &nfsi->open_states);
723                 ihold(inode);
724                 state->inode = inode;
725                 spin_unlock(&inode->i_lock);
726                 /* Note: The reclaim code dictates that we add stateless
727                  * and read-only stateids to the end of the list */
728                 list_add_tail(&state->open_states, &owner->so_states);
729                 spin_unlock(&owner->so_lock);
730         } else {
731                 spin_unlock(&inode->i_lock);
732                 spin_unlock(&owner->so_lock);
733                 if (new)
734                         nfs4_free_open_state(new);
735         }
736 out:
737         return state;
738 }
739
740 void nfs4_put_open_state(struct nfs4_state *state)
741 {
742         struct inode *inode = state->inode;
743         struct nfs4_state_owner *owner = state->owner;
744
745         if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
746                 return;
747         spin_lock(&inode->i_lock);
748         list_del(&state->inode_states);
749         list_del(&state->open_states);
750         spin_unlock(&inode->i_lock);
751         spin_unlock(&owner->so_lock);
752         iput(inode);
753         nfs4_free_open_state(state);
754         nfs4_put_state_owner(owner);
755 }
756
757 /*
758  * Close the current file.
759  */
760 static void __nfs4_close(struct nfs4_state *state,
761                 fmode_t fmode, gfp_t gfp_mask, int wait)
762 {
763         struct nfs4_state_owner *owner = state->owner;
764         int call_close = 0;
765         fmode_t newstate;
766
767         atomic_inc(&owner->so_count);
768         /* Protect against nfs4_find_state() */
769         spin_lock(&owner->so_lock);
770         switch (fmode & (FMODE_READ | FMODE_WRITE)) {
771                 case FMODE_READ:
772                         state->n_rdonly--;
773                         break;
774                 case FMODE_WRITE:
775                         state->n_wronly--;
776                         break;
777                 case FMODE_READ|FMODE_WRITE:
778                         state->n_rdwr--;
779         }
780         newstate = FMODE_READ|FMODE_WRITE;
781         if (state->n_rdwr == 0) {
782                 if (state->n_rdonly == 0) {
783                         newstate &= ~FMODE_READ;
784                         call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
785                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
786                 }
787                 if (state->n_wronly == 0) {
788                         newstate &= ~FMODE_WRITE;
789                         call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
790                         call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
791                 }
792                 if (newstate == 0)
793                         clear_bit(NFS_DELEGATED_STATE, &state->flags);
794         }
795         nfs4_state_set_mode_locked(state, newstate);
796         spin_unlock(&owner->so_lock);
797
798         if (!call_close) {
799                 nfs4_put_open_state(state);
800                 nfs4_put_state_owner(owner);
801         } else
802                 nfs4_do_close(state, gfp_mask, wait);
803 }
804
805 void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
806 {
807         __nfs4_close(state, fmode, GFP_NOFS, 0);
808 }
809
810 void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
811 {
812         __nfs4_close(state, fmode, GFP_KERNEL, 1);
813 }
814
815 /*
816  * Search the state->lock_states for an existing lock_owner
817  * that is compatible with current->files
818  */
819 static struct nfs4_lock_state *
820 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
821 {
822         struct nfs4_lock_state *pos;
823         list_for_each_entry(pos, &state->lock_states, ls_locks) {
824                 if (type != NFS4_ANY_LOCK_TYPE && pos->ls_owner.lo_type != type)
825                         continue;
826                 switch (pos->ls_owner.lo_type) {
827                 case NFS4_POSIX_LOCK_TYPE:
828                         if (pos->ls_owner.lo_u.posix_owner != fl_owner)
829                                 continue;
830                         break;
831                 case NFS4_FLOCK_LOCK_TYPE:
832                         if (pos->ls_owner.lo_u.flock_owner != fl_pid)
833                                 continue;
834                 }
835                 atomic_inc(&pos->ls_count);
836                 return pos;
837         }
838         return NULL;
839 }
840
841 /*
842  * Return a compatible lock_state. If no initialized lock_state structure
843  * exists, return an uninitialized one.
844  *
845  */
846 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)
847 {
848         struct nfs4_lock_state *lsp;
849         struct nfs_server *server = state->owner->so_server;
850
851         lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
852         if (lsp == NULL)
853                 return NULL;
854         nfs4_init_seqid_counter(&lsp->ls_seqid);
855         atomic_set(&lsp->ls_count, 1);
856         lsp->ls_state = state;
857         lsp->ls_owner.lo_type = type;
858         switch (lsp->ls_owner.lo_type) {
859         case NFS4_FLOCK_LOCK_TYPE:
860                 lsp->ls_owner.lo_u.flock_owner = fl_pid;
861                 break;
862         case NFS4_POSIX_LOCK_TYPE:
863                 lsp->ls_owner.lo_u.posix_owner = fl_owner;
864                 break;
865         default:
866                 goto out_free;
867         }
868         lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS);
869         if (lsp->ls_seqid.owner_id < 0)
870                 goto out_free;
871         INIT_LIST_HEAD(&lsp->ls_locks);
872         return lsp;
873 out_free:
874         kfree(lsp);
875         return NULL;
876 }
877
878 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
879 {
880         ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id);
881         nfs4_destroy_seqid_counter(&lsp->ls_seqid);
882         kfree(lsp);
883 }
884
885 /*
886  * Return a compatible lock_state. If no initialized lock_state structure
887  * exists, return an uninitialized one.
888  *
889  */
890 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner, pid_t pid, unsigned int type)
891 {
892         struct nfs4_lock_state *lsp, *new = NULL;
893         
894         for(;;) {
895                 spin_lock(&state->state_lock);
896                 lsp = __nfs4_find_lock_state(state, owner, pid, type);
897                 if (lsp != NULL)
898                         break;
899                 if (new != NULL) {
900                         list_add(&new->ls_locks, &state->lock_states);
901                         set_bit(LK_STATE_IN_USE, &state->flags);
902                         lsp = new;
903                         new = NULL;
904                         break;
905                 }
906                 spin_unlock(&state->state_lock);
907                 new = nfs4_alloc_lock_state(state, owner, pid, type);
908                 if (new == NULL)
909                         return NULL;
910         }
911         spin_unlock(&state->state_lock);
912         if (new != NULL)
913                 nfs4_free_lock_state(state->owner->so_server, new);
914         return lsp;
915 }
916
917 /*
918  * Release reference to lock_state, and free it if we see that
919  * it is no longer in use
920  */
921 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
922 {
923         struct nfs_server *server;
924         struct nfs4_state *state;
925
926         if (lsp == NULL)
927                 return;
928         state = lsp->ls_state;
929         if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
930                 return;
931         list_del(&lsp->ls_locks);
932         if (list_empty(&state->lock_states))
933                 clear_bit(LK_STATE_IN_USE, &state->flags);
934         spin_unlock(&state->state_lock);
935         server = state->owner->so_server;
936         if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
937                 struct nfs_client *clp = server->nfs_client;
938
939                 clp->cl_mvops->free_lock_state(server, lsp);
940         } else
941                 nfs4_free_lock_state(server, lsp);
942 }
943
944 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
945 {
946         struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
947
948         dst->fl_u.nfs4_fl.owner = lsp;
949         atomic_inc(&lsp->ls_count);
950 }
951
952 static void nfs4_fl_release_lock(struct file_lock *fl)
953 {
954         nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
955 }
956
957 static const struct file_lock_operations nfs4_fl_lock_ops = {
958         .fl_copy_lock = nfs4_fl_copy_lock,
959         .fl_release_private = nfs4_fl_release_lock,
960 };
961
962 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
963 {
964         struct nfs4_lock_state *lsp;
965
966         if (fl->fl_ops != NULL)
967                 return 0;
968         if (fl->fl_flags & FL_POSIX)
969                 lsp = nfs4_get_lock_state(state, fl->fl_owner, 0, NFS4_POSIX_LOCK_TYPE);
970         else if (fl->fl_flags & FL_FLOCK)
971                 lsp = nfs4_get_lock_state(state, NULL, fl->fl_pid,
972                                 NFS4_FLOCK_LOCK_TYPE);
973         else
974                 return -EINVAL;
975         if (lsp == NULL)
976                 return -ENOMEM;
977         fl->fl_u.nfs4_fl.owner = lsp;
978         fl->fl_ops = &nfs4_fl_lock_ops;
979         return 0;
980 }
981
982 static int nfs4_copy_lock_stateid(nfs4_stateid *dst,
983                 struct nfs4_state *state,
984                 const struct nfs_lockowner *lockowner)
985 {
986         struct nfs4_lock_state *lsp;
987         fl_owner_t fl_owner;
988         pid_t fl_pid;
989         int ret = -ENOENT;
990
991
992         if (lockowner == NULL)
993                 goto out;
994
995         if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
996                 goto out;
997
998         fl_owner = lockowner->l_owner;
999         fl_pid = lockowner->l_pid;
1000         spin_lock(&state->state_lock);
1001         lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
1002         if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
1003                 nfs4_stateid_copy(dst, &lsp->ls_stateid);
1004                 ret = 0;
1005                 smp_rmb();
1006                 if (!list_empty(&lsp->ls_seqid.list))
1007                         ret = -EWOULDBLOCK;
1008         }
1009         spin_unlock(&state->state_lock);
1010         nfs4_put_lock_state(lsp);
1011 out:
1012         return ret;
1013 }
1014
1015 static int nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
1016 {
1017         const nfs4_stateid *src;
1018         int ret;
1019         int seq;
1020
1021         do {
1022                 src = &zero_stateid;
1023                 seq = read_seqbegin(&state->seqlock);
1024                 if (test_bit(NFS_OPEN_STATE, &state->flags))
1025                         src = &state->open_stateid;
1026                 nfs4_stateid_copy(dst, src);
1027                 ret = 0;
1028                 smp_rmb();
1029                 if (!list_empty(&state->owner->so_seqid.list))
1030                         ret = -EWOULDBLOCK;
1031         } while (read_seqretry(&state->seqlock, seq));
1032         return ret;
1033 }
1034
1035 /*
1036  * Byte-range lock aware utility to initialize the stateid of read/write
1037  * requests.
1038  */
1039 int nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
1040                 fmode_t fmode, const struct nfs_lockowner *lockowner)
1041 {
1042         int ret = 0;
1043         if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
1044                 goto out;
1045         ret = nfs4_copy_lock_stateid(dst, state, lockowner);
1046         if (ret != -ENOENT)
1047                 goto out;
1048         ret = nfs4_copy_open_stateid(dst, state);
1049 out:
1050         if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41))
1051                 dst->seqid = 0;
1052         return ret;
1053 }
1054
1055 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
1056 {
1057         struct nfs_seqid *new;
1058
1059         new = kmalloc(sizeof(*new), gfp_mask);
1060         if (new != NULL) {
1061                 new->sequence = counter;
1062                 INIT_LIST_HEAD(&new->list);
1063                 new->task = NULL;
1064         }
1065         return new;
1066 }
1067
1068 void nfs_release_seqid(struct nfs_seqid *seqid)
1069 {
1070         struct nfs_seqid_counter *sequence;
1071
1072         if (list_empty(&seqid->list))
1073                 return;
1074         sequence = seqid->sequence;
1075         spin_lock(&sequence->lock);
1076         list_del_init(&seqid->list);
1077         if (!list_empty(&sequence->list)) {
1078                 struct nfs_seqid *next;
1079
1080                 next = list_first_entry(&sequence->list,
1081                                 struct nfs_seqid, list);
1082                 rpc_wake_up_queued_task(&sequence->wait, next->task);
1083         }
1084         spin_unlock(&sequence->lock);
1085 }
1086
1087 void nfs_free_seqid(struct nfs_seqid *seqid)
1088 {
1089         nfs_release_seqid(seqid);
1090         kfree(seqid);
1091 }
1092
1093 /*
1094  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
1095  * failed with a seqid incrementing error -
1096  * see comments nfs_fs.h:seqid_mutating_error()
1097  */
1098 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
1099 {
1100         switch (status) {
1101                 case 0:
1102                         break;
1103                 case -NFS4ERR_BAD_SEQID:
1104                         if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
1105                                 return;
1106                         pr_warn_ratelimited("NFS: v4 server returned a bad"
1107                                         " sequence-id error on an"
1108                                         " unconfirmed sequence %p!\n",
1109                                         seqid->sequence);
1110                 case -NFS4ERR_STALE_CLIENTID:
1111                 case -NFS4ERR_STALE_STATEID:
1112                 case -NFS4ERR_BAD_STATEID:
1113                 case -NFS4ERR_BADXDR:
1114                 case -NFS4ERR_RESOURCE:
1115                 case -NFS4ERR_NOFILEHANDLE:
1116                         /* Non-seqid mutating errors */
1117                         return;
1118         };
1119         /*
1120          * Note: no locking needed as we are guaranteed to be first
1121          * on the sequence list
1122          */
1123         seqid->sequence->counter++;
1124 }
1125
1126 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
1127 {
1128         struct nfs4_state_owner *sp = container_of(seqid->sequence,
1129                                         struct nfs4_state_owner, so_seqid);
1130         struct nfs_server *server = sp->so_server;
1131
1132         if (status == -NFS4ERR_BAD_SEQID)
1133                 nfs4_drop_state_owner(sp);
1134         if (!nfs4_has_session(server->nfs_client))
1135                 nfs_increment_seqid(status, seqid);
1136 }
1137
1138 /*
1139  * Increment the seqid if the LOCK/LOCKU succeeded, or
1140  * failed with a seqid incrementing error -
1141  * see comments nfs_fs.h:seqid_mutating_error()
1142  */
1143 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
1144 {
1145         nfs_increment_seqid(status, seqid);
1146 }
1147
1148 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
1149 {
1150         struct nfs_seqid_counter *sequence = seqid->sequence;
1151         int status = 0;
1152
1153         spin_lock(&sequence->lock);
1154         seqid->task = task;
1155         if (list_empty(&seqid->list))
1156                 list_add_tail(&seqid->list, &sequence->list);
1157         if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
1158                 goto unlock;
1159         rpc_sleep_on(&sequence->wait, task, NULL);
1160         status = -EAGAIN;
1161 unlock:
1162         spin_unlock(&sequence->lock);
1163         return status;
1164 }
1165
1166 static int nfs4_run_state_manager(void *);
1167
1168 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
1169 {
1170         smp_mb__before_clear_bit();
1171         clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
1172         smp_mb__after_clear_bit();
1173         wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
1174         rpc_wake_up(&clp->cl_rpcwaitq);
1175 }
1176
1177 /*
1178  * Schedule the nfs_client asynchronous state management routine
1179  */
1180 void nfs4_schedule_state_manager(struct nfs_client *clp)
1181 {
1182         struct task_struct *task;
1183         char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
1184
1185         if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1186                 return;
1187         __module_get(THIS_MODULE);
1188         atomic_inc(&clp->cl_count);
1189
1190         /* The rcu_read_lock() is not strictly necessary, as the state
1191          * manager is the only thread that ever changes the rpc_xprt
1192          * after it's initialized.  At this point, we're single threaded. */
1193         rcu_read_lock();
1194         snprintf(buf, sizeof(buf), "%s-manager",
1195                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
1196         rcu_read_unlock();
1197         task = kthread_run(nfs4_run_state_manager, clp, buf);
1198         if (IS_ERR(task)) {
1199                 printk(KERN_ERR "%s: kthread_run: %ld\n",
1200                         __func__, PTR_ERR(task));
1201                 nfs4_clear_state_manager_bit(clp);
1202                 nfs_put_client(clp);
1203                 module_put(THIS_MODULE);
1204         }
1205 }
1206
1207 /*
1208  * Schedule a lease recovery attempt
1209  */
1210 void nfs4_schedule_lease_recovery(struct nfs_client *clp)
1211 {
1212         if (!clp)
1213                 return;
1214         if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1215                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1216         dprintk("%s: scheduling lease recovery for server %s\n", __func__,
1217                         clp->cl_hostname);
1218         nfs4_schedule_state_manager(clp);
1219 }
1220 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
1221
1222 int nfs4_wait_clnt_recover(struct nfs_client *clp)
1223 {
1224         int res;
1225
1226         might_sleep();
1227
1228         res = wait_on_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
1229                         nfs_wait_bit_killable, TASK_KILLABLE);
1230         if (res)
1231                 return res;
1232
1233         if (clp->cl_cons_state < 0)
1234                 return clp->cl_cons_state;
1235         return 0;
1236 }
1237
1238 int nfs4_client_recover_expired_lease(struct nfs_client *clp)
1239 {
1240         unsigned int loop;
1241         int ret;
1242
1243         for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) {
1244                 ret = nfs4_wait_clnt_recover(clp);
1245                 if (ret != 0)
1246                         break;
1247                 if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) &&
1248                     !test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state))
1249                         break;
1250                 nfs4_schedule_state_manager(clp);
1251                 ret = -EIO;
1252         }
1253         return ret;
1254 }
1255
1256 /*
1257  * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
1258  * @clp: client to process
1259  *
1260  * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
1261  * resend of the SETCLIENTID and hence re-establish the
1262  * callback channel. Then return all existing delegations.
1263  */
1264 static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
1265 {
1266         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1267         nfs_expire_all_delegations(clp);
1268         dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__,
1269                         clp->cl_hostname);
1270 }
1271
1272 void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
1273 {
1274         nfs40_handle_cb_pathdown(clp);
1275         nfs4_schedule_state_manager(clp);
1276 }
1277
1278 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
1279 {
1280
1281         set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1282         /* Don't recover state that expired before the reboot */
1283         if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
1284                 clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1285                 return 0;
1286         }
1287         set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
1288         set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1289         return 1;
1290 }
1291
1292 static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
1293 {
1294         set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
1295         clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
1296         set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
1297         set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1298         return 1;
1299 }
1300
1301 int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
1302 {
1303         struct nfs_client *clp = server->nfs_client;
1304
1305         if (!nfs4_valid_open_stateid(state))
1306                 return -EBADF;
1307         nfs4_state_mark_reclaim_nograce(clp, state);
1308         dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
1309                         clp->cl_hostname);
1310         nfs4_schedule_state_manager(clp);
1311         return 0;
1312 }
1313 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
1314
1315 void nfs_inode_find_state_and_recover(struct inode *inode,
1316                 const nfs4_stateid *stateid)
1317 {
1318         struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
1319         struct nfs_inode *nfsi = NFS_I(inode);
1320         struct nfs_open_context *ctx;
1321         struct nfs4_state *state;
1322         bool found = false;
1323
1324         spin_lock(&inode->i_lock);
1325         list_for_each_entry(ctx, &nfsi->open_files, list) {
1326                 state = ctx->state;
1327                 if (state == NULL)
1328                         continue;
1329                 if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
1330                         continue;
1331                 if (!nfs4_stateid_match(&state->stateid, stateid))
1332                         continue;
1333                 nfs4_state_mark_reclaim_nograce(clp, state);
1334                 found = true;
1335         }
1336         spin_unlock(&inode->i_lock);
1337         if (found)
1338                 nfs4_schedule_state_manager(clp);
1339 }
1340
1341 static void nfs4_state_mark_open_context_bad(struct nfs4_state *state)
1342 {
1343         struct inode *inode = state->inode;
1344         struct nfs_inode *nfsi = NFS_I(inode);
1345         struct nfs_open_context *ctx;
1346
1347         spin_lock(&inode->i_lock);
1348         list_for_each_entry(ctx, &nfsi->open_files, list) {
1349                 if (ctx->state != state)
1350                         continue;
1351                 set_bit(NFS_CONTEXT_BAD, &ctx->flags);
1352         }
1353         spin_unlock(&inode->i_lock);
1354 }
1355
1356 static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)
1357 {
1358         set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags);
1359         nfs4_state_mark_open_context_bad(state);
1360 }
1361
1362
1363 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
1364 {
1365         struct inode *inode = state->inode;
1366         struct nfs_inode *nfsi = NFS_I(inode);
1367         struct file_lock *fl;
1368         int status = 0;
1369
1370         if (inode->i_flock == NULL)
1371                 return 0;
1372
1373         /* Guard against delegation returns and new lock/unlock calls */
1374         down_write(&nfsi->rwsem);
1375         /* Protect inode->i_flock using the BKL */
1376         lock_flocks();
1377         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
1378                 if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
1379                         continue;
1380                 if (nfs_file_open_context(fl->fl_file)->state != state)
1381                         continue;
1382                 unlock_flocks();
1383                 status = ops->recover_lock(state, fl);
1384                 switch (status) {
1385                         case 0:
1386                                 break;
1387                         case -ESTALE:
1388                         case -NFS4ERR_ADMIN_REVOKED:
1389                         case -NFS4ERR_STALE_STATEID:
1390                         case -NFS4ERR_BAD_STATEID:
1391                         case -NFS4ERR_EXPIRED:
1392                         case -NFS4ERR_NO_GRACE:
1393                         case -NFS4ERR_STALE_CLIENTID:
1394                         case -NFS4ERR_BADSESSION:
1395                         case -NFS4ERR_BADSLOT:
1396                         case -NFS4ERR_BAD_HIGH_SLOT:
1397                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1398                                 goto out;
1399                         default:
1400                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1401                                         "Zeroing state\n", __func__, status);
1402                         case -ENOMEM:
1403                         case -NFS4ERR_DENIED:
1404                         case -NFS4ERR_RECLAIM_BAD:
1405                         case -NFS4ERR_RECLAIM_CONFLICT:
1406                                 /* kill_proc(fl->fl_pid, SIGLOST, 1); */
1407                                 status = 0;
1408                 }
1409                 lock_flocks();
1410         }
1411         unlock_flocks();
1412 out:
1413         up_write(&nfsi->rwsem);
1414         return status;
1415 }
1416
1417 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
1418 {
1419         struct nfs4_state *state;
1420         struct nfs4_lock_state *lock;
1421         int status = 0;
1422
1423         /* Note: we rely on the sp->so_states list being ordered 
1424          * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
1425          * states first.
1426          * This is needed to ensure that the server won't give us any
1427          * read delegations that we have to return if, say, we are
1428          * recovering after a network partition or a reboot from a
1429          * server that doesn't support a grace period.
1430          */
1431         spin_lock(&sp->so_lock);
1432         write_seqcount_begin(&sp->so_reclaim_seqcount);
1433 restart:
1434         list_for_each_entry(state, &sp->so_states, open_states) {
1435                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
1436                         continue;
1437                 if (!nfs4_valid_open_stateid(state))
1438                         continue;
1439                 if (state->state == 0)
1440                         continue;
1441                 atomic_inc(&state->count);
1442                 spin_unlock(&sp->so_lock);
1443                 status = ops->recover_open(sp, state);
1444                 if (status >= 0) {
1445                         status = nfs4_reclaim_locks(state, ops);
1446                         if (status >= 0) {
1447                                 spin_lock(&state->state_lock);
1448                                 list_for_each_entry(lock, &state->lock_states, ls_locks) {
1449                                         if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
1450                                                 pr_warn_ratelimited("NFS: "
1451                                                         "%s: Lock reclaim "
1452                                                         "failed!\n", __func__);
1453                                 }
1454                                 spin_unlock(&state->state_lock);
1455                                 nfs4_put_open_state(state);
1456                                 spin_lock(&sp->so_lock);
1457                                 goto restart;
1458                         }
1459                 }
1460                 switch (status) {
1461                         default:
1462                                 printk(KERN_ERR "NFS: %s: unhandled error %d. "
1463                                         "Zeroing state\n", __func__, status);
1464                         case -ENOENT:
1465                         case -ENOMEM:
1466                         case -ESTALE:
1467                                 /*
1468                                  * Open state on this file cannot be recovered
1469                                  * All we can do is revert to using the zero stateid.
1470                                  */
1471                                 nfs4_state_mark_recovery_failed(state, status);
1472                                 break;
1473                         case -EAGAIN:
1474                                 ssleep(1);
1475                         case -NFS4ERR_ADMIN_REVOKED:
1476                         case -NFS4ERR_STALE_STATEID:
1477                         case -NFS4ERR_BAD_STATEID:
1478                         case -NFS4ERR_RECLAIM_BAD:
1479                         case -NFS4ERR_RECLAIM_CONFLICT:
1480                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1481                                 break;
1482                         case -NFS4ERR_EXPIRED:
1483                         case -NFS4ERR_NO_GRACE:
1484                                 nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
1485                         case -NFS4ERR_STALE_CLIENTID:
1486                         case -NFS4ERR_BADSESSION:
1487                         case -NFS4ERR_BADSLOT:
1488                         case -NFS4ERR_BAD_HIGH_SLOT:
1489                         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1490                                 goto out_err;
1491                 }
1492                 nfs4_put_open_state(state);
1493                 spin_lock(&sp->so_lock);
1494                 goto restart;
1495         }
1496         write_seqcount_end(&sp->so_reclaim_seqcount);
1497         spin_unlock(&sp->so_lock);
1498         return 0;
1499 out_err:
1500         nfs4_put_open_state(state);
1501         spin_lock(&sp->so_lock);
1502         write_seqcount_end(&sp->so_reclaim_seqcount);
1503         spin_unlock(&sp->so_lock);
1504         return status;
1505 }
1506
1507 static void nfs4_clear_open_state(struct nfs4_state *state)
1508 {
1509         struct nfs4_lock_state *lock;
1510
1511         clear_bit(NFS_DELEGATED_STATE, &state->flags);
1512         clear_bit(NFS_O_RDONLY_STATE, &state->flags);
1513         clear_bit(NFS_O_WRONLY_STATE, &state->flags);
1514         clear_bit(NFS_O_RDWR_STATE, &state->flags);
1515         spin_lock(&state->state_lock);
1516         list_for_each_entry(lock, &state->lock_states, ls_locks) {
1517                 lock->ls_seqid.flags = 0;
1518                 clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags);
1519         }
1520         spin_unlock(&state->state_lock);
1521 }
1522
1523 static void nfs4_reset_seqids(struct nfs_server *server,
1524         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1525 {
1526         struct nfs_client *clp = server->nfs_client;
1527         struct nfs4_state_owner *sp;
1528         struct rb_node *pos;
1529         struct nfs4_state *state;
1530
1531         spin_lock(&clp->cl_lock);
1532         for (pos = rb_first(&server->state_owners);
1533              pos != NULL;
1534              pos = rb_next(pos)) {
1535                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1536                 sp->so_seqid.flags = 0;
1537                 spin_lock(&sp->so_lock);
1538                 list_for_each_entry(state, &sp->so_states, open_states) {
1539                         if (mark_reclaim(clp, state))
1540                                 nfs4_clear_open_state(state);
1541                 }
1542                 spin_unlock(&sp->so_lock);
1543         }
1544         spin_unlock(&clp->cl_lock);
1545 }
1546
1547 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
1548         int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
1549 {
1550         struct nfs_server *server;
1551
1552         rcu_read_lock();
1553         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1554                 nfs4_reset_seqids(server, mark_reclaim);
1555         rcu_read_unlock();
1556 }
1557
1558 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1559 {
1560         /* Mark all delegations for reclaim */
1561         nfs_delegation_mark_reclaim(clp);
1562         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1563 }
1564
1565 static void nfs4_reclaim_complete(struct nfs_client *clp,
1566                                  const struct nfs4_state_recovery_ops *ops)
1567 {
1568         /* Notify the server we're done reclaiming our state */
1569         if (ops->reclaim_complete)
1570                 (void)ops->reclaim_complete(clp);
1571 }
1572
1573 static void nfs4_clear_reclaim_server(struct nfs_server *server)
1574 {
1575         struct nfs_client *clp = server->nfs_client;
1576         struct nfs4_state_owner *sp;
1577         struct rb_node *pos;
1578         struct nfs4_state *state;
1579
1580         spin_lock(&clp->cl_lock);
1581         for (pos = rb_first(&server->state_owners);
1582              pos != NULL;
1583              pos = rb_next(pos)) {
1584                 sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
1585                 spin_lock(&sp->so_lock);
1586                 list_for_each_entry(state, &sp->so_states, open_states) {
1587                         if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
1588                                                 &state->flags))
1589                                 continue;
1590                         nfs4_state_mark_reclaim_nograce(clp, state);
1591                 }
1592                 spin_unlock(&sp->so_lock);
1593         }
1594         spin_unlock(&clp->cl_lock);
1595 }
1596
1597 static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
1598 {
1599         struct nfs_server *server;
1600
1601         if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1602                 return 0;
1603
1604         rcu_read_lock();
1605         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
1606                 nfs4_clear_reclaim_server(server);
1607         rcu_read_unlock();
1608
1609         nfs_delegation_reap_unclaimed(clp);
1610         return 1;
1611 }
1612
1613 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1614 {
1615         if (!nfs4_state_clear_reclaim_reboot(clp))
1616                 return;
1617         nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
1618 }
1619
1620 static void nfs_delegation_clear_all(struct nfs_client *clp)
1621 {
1622         nfs_delegation_mark_reclaim(clp);
1623         nfs_delegation_reap_unclaimed(clp);
1624 }
1625
1626 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1627 {
1628         nfs_delegation_clear_all(clp);
1629         nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1630 }
1631
1632 static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1633 {
1634         switch (error) {
1635                 case 0:
1636                         break;
1637                 case -NFS4ERR_CB_PATH_DOWN:
1638                         nfs40_handle_cb_pathdown(clp);
1639                         break;
1640                 case -NFS4ERR_NO_GRACE:
1641                         nfs4_state_end_reclaim_reboot(clp);
1642                         break;
1643                 case -NFS4ERR_STALE_CLIENTID:
1644                 case -NFS4ERR_LEASE_MOVED:
1645                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1646                         nfs4_state_clear_reclaim_reboot(clp);
1647                         nfs4_state_start_reclaim_reboot(clp);
1648                         break;
1649                 case -NFS4ERR_EXPIRED:
1650                         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1651                         nfs4_state_start_reclaim_nograce(clp);
1652                         break;
1653                 case -NFS4ERR_BADSESSION:
1654                 case -NFS4ERR_BADSLOT:
1655                 case -NFS4ERR_BAD_HIGH_SLOT:
1656                 case -NFS4ERR_DEADSESSION:
1657                 case -NFS4ERR_SEQ_FALSE_RETRY:
1658                 case -NFS4ERR_SEQ_MISORDERED:
1659                         set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1660                         /* Zero session reset errors */
1661                         break;
1662                 case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1663                         set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1664                         break;
1665                 default:
1666                         dprintk("%s: failed to handle error %d for server %s\n",
1667                                         __func__, error, clp->cl_hostname);
1668                         return error;
1669         }
1670         dprintk("%s: handled error %d for server %s\n", __func__, error,
1671                         clp->cl_hostname);
1672         return 0;
1673 }
1674
1675 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1676 {
1677         struct nfs4_state_owner *sp;
1678         struct nfs_server *server;
1679         struct rb_node *pos;
1680         int status = 0;
1681
1682 restart:
1683         rcu_read_lock();
1684         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
1685                 nfs4_purge_state_owners(server);
1686                 spin_lock(&clp->cl_lock);
1687                 for (pos = rb_first(&server->state_owners);
1688                      pos != NULL;
1689                      pos = rb_next(pos)) {
1690                         sp = rb_entry(pos,
1691                                 struct nfs4_state_owner, so_server_node);
1692                         if (!test_and_clear_bit(ops->owner_flag_bit,
1693                                                         &sp->so_flags))
1694                                 continue;
1695                         atomic_inc(&sp->so_count);
1696                         spin_unlock(&clp->cl_lock);
1697                         rcu_read_unlock();
1698
1699                         status = nfs4_reclaim_open_state(sp, ops);
1700                         if (status < 0) {
1701                                 set_bit(ops->owner_flag_bit, &sp->so_flags);
1702                                 nfs4_put_state_owner(sp);
1703                                 return nfs4_recovery_handle_error(clp, status);
1704                         }
1705
1706                         nfs4_put_state_owner(sp);
1707                         goto restart;
1708                 }
1709                 spin_unlock(&clp->cl_lock);
1710         }
1711         rcu_read_unlock();
1712         return status;
1713 }
1714
1715 static int nfs4_check_lease(struct nfs_client *clp)
1716 {
1717         struct rpc_cred *cred;
1718         const struct nfs4_state_maintenance_ops *ops =
1719                 clp->cl_mvops->state_renewal_ops;
1720         int status;
1721
1722         /* Is the client already known to have an expired lease? */
1723         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1724                 return 0;
1725         spin_lock(&clp->cl_lock);
1726         cred = ops->get_state_renewal_cred_locked(clp);
1727         spin_unlock(&clp->cl_lock);
1728         if (cred == NULL) {
1729                 cred = nfs4_get_setclientid_cred(clp);
1730                 status = -ENOKEY;
1731                 if (cred == NULL)
1732                         goto out;
1733         }
1734         status = ops->renew_lease(clp, cred);
1735         put_rpccred(cred);
1736         if (status == -ETIMEDOUT) {
1737                 set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1738                 return 0;
1739         }
1740 out:
1741         return nfs4_recovery_handle_error(clp, status);
1742 }
1743
1744 /* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors
1745  * and for recoverable errors on EXCHANGE_ID for v4.1
1746  */
1747 static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
1748 {
1749         switch (status) {
1750         case -NFS4ERR_SEQ_MISORDERED:
1751                 if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
1752                         return -ESERVERFAULT;
1753                 /* Lease confirmation error: retry after purging the lease */
1754                 ssleep(1);
1755                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1756                 break;
1757         case -NFS4ERR_STALE_CLIENTID:
1758                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1759                 nfs4_state_clear_reclaim_reboot(clp);
1760                 nfs4_state_start_reclaim_reboot(clp);
1761                 break;
1762         case -NFS4ERR_CLID_INUSE:
1763                 pr_err("NFS: Server %s reports our clientid is in use\n",
1764                         clp->cl_hostname);
1765                 nfs_mark_client_ready(clp, -EPERM);
1766                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1767                 return -EPERM;
1768         case -EACCES:
1769         case -NFS4ERR_DELAY:
1770         case -ETIMEDOUT:
1771         case -EAGAIN:
1772                 ssleep(1);
1773                 break;
1774
1775         case -NFS4ERR_MINOR_VERS_MISMATCH:
1776                 if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1777                         nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
1778                 dprintk("%s: exit with error %d for server %s\n",
1779                                 __func__, -EPROTONOSUPPORT, clp->cl_hostname);
1780                 return -EPROTONOSUPPORT;
1781         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1782                                  * in nfs4_exchange_id */
1783         default:
1784                 dprintk("%s: exit with error %d for server %s\n", __func__,
1785                                 status, clp->cl_hostname);
1786                 return status;
1787         }
1788         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1789         dprintk("%s: handled error %d for server %s\n", __func__, status,
1790                         clp->cl_hostname);
1791         return 0;
1792 }
1793
1794 static int nfs4_establish_lease(struct nfs_client *clp)
1795 {
1796         struct rpc_cred *cred;
1797         const struct nfs4_state_recovery_ops *ops =
1798                 clp->cl_mvops->reboot_recovery_ops;
1799         int status;
1800
1801         cred = ops->get_clid_cred(clp);
1802         if (cred == NULL)
1803                 return -ENOENT;
1804         status = ops->establish_clid(clp, cred);
1805         put_rpccred(cred);
1806         if (status != 0)
1807                 return status;
1808         pnfs_destroy_all_layouts(clp);
1809         return 0;
1810 }
1811
1812 /*
1813  * Returns zero or a negative errno.  NFS4ERR values are converted
1814  * to local errno values.
1815  */
1816 static int nfs4_reclaim_lease(struct nfs_client *clp)
1817 {
1818         int status;
1819
1820         status = nfs4_establish_lease(clp);
1821         if (status < 0)
1822                 return nfs4_handle_reclaim_lease_error(clp, status);
1823         if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state))
1824                 nfs4_state_start_reclaim_nograce(clp);
1825         if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
1826                 set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
1827         clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1828         clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1829         return 0;
1830 }
1831
1832 static int nfs4_purge_lease(struct nfs_client *clp)
1833 {
1834         int status;
1835
1836         status = nfs4_establish_lease(clp);
1837         if (status < 0)
1838                 return nfs4_handle_reclaim_lease_error(clp, status);
1839         clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1840         set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1841         nfs4_state_start_reclaim_nograce(clp);
1842         return 0;
1843 }
1844
1845 /**
1846  * nfs4_discover_server_trunking - Detect server IP address trunking
1847  *
1848  * @clp: nfs_client under test
1849  * @result: OUT: found nfs_client, or clp
1850  *
1851  * Returns zero or a negative errno.  If zero is returned,
1852  * an nfs_client pointer is planted in "result".
1853  *
1854  * Note: since we are invoked in process context, and
1855  * not from inside the state manager, we cannot use
1856  * nfs4_handle_reclaim_lease_error().
1857  */
1858 int nfs4_discover_server_trunking(struct nfs_client *clp,
1859                                   struct nfs_client **result)
1860 {
1861         const struct nfs4_state_recovery_ops *ops =
1862                                 clp->cl_mvops->reboot_recovery_ops;
1863         struct rpc_clnt *clnt;
1864         struct rpc_cred *cred;
1865         int i, status;
1866
1867         dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
1868
1869         clnt = clp->cl_rpcclient;
1870         i = 0;
1871
1872         mutex_lock(&nfs_clid_init_mutex);
1873 again:
1874         status  = -ENOENT;
1875         cred = ops->get_clid_cred(clp);
1876         if (cred == NULL)
1877                 goto out_unlock;
1878
1879         status = ops->detect_trunking(clp, result, cred);
1880         put_rpccred(cred);
1881         switch (status) {
1882         case 0:
1883                 break;
1884         case -NFS4ERR_DELAY:
1885         case -ETIMEDOUT:
1886         case -EAGAIN:
1887                 ssleep(1);
1888         case -NFS4ERR_STALE_CLIENTID:
1889                 dprintk("NFS: %s after status %d, retrying\n",
1890                         __func__, status);
1891                 goto again;
1892         case -EACCES:
1893                 if (i++)
1894                         break;
1895         case -NFS4ERR_CLID_INUSE:
1896         case -NFS4ERR_WRONGSEC:
1897                 clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
1898                 if (IS_ERR(clnt)) {
1899                         status = PTR_ERR(clnt);
1900                         break;
1901                 }
1902                 /* Note: this is safe because we haven't yet marked the
1903                  * client as ready, so we are the only user of
1904                  * clp->cl_rpcclient
1905                  */
1906                 clnt = xchg(&clp->cl_rpcclient, clnt);
1907                 rpc_shutdown_client(clnt);
1908                 clnt = clp->cl_rpcclient;
1909                 goto again;
1910
1911         case -NFS4ERR_MINOR_VERS_MISMATCH:
1912                 status = -EPROTONOSUPPORT;
1913                 break;
1914
1915         case -EKEYEXPIRED:
1916         case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1917                                  * in nfs4_exchange_id */
1918                 status = -EKEYEXPIRED;
1919                 break;
1920         default:
1921                 pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
1922                                 __func__, status);
1923                 status = -EIO;
1924         }
1925
1926 out_unlock:
1927         mutex_unlock(&nfs_clid_init_mutex);
1928         dprintk("NFS: %s: status = %d\n", __func__, status);
1929         return status;
1930 }
1931
1932 #ifdef CONFIG_NFS_V4_1
1933 void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
1934 {
1935         struct nfs_client *clp = session->clp;
1936
1937         switch (err) {
1938         default:
1939                 set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
1940                 break;
1941         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1942                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
1943         }
1944         nfs4_schedule_lease_recovery(clp);
1945 }
1946 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
1947
1948 static void nfs41_ping_server(struct nfs_client *clp)
1949 {
1950         /* Use CHECK_LEASE to ping the server with a SEQUENCE */
1951         set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1952         nfs4_schedule_state_manager(clp);
1953 }
1954
1955 void nfs41_server_notify_target_slotid_update(struct nfs_client *clp)
1956 {
1957         nfs41_ping_server(clp);
1958 }
1959
1960 void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp)
1961 {
1962         nfs41_ping_server(clp);
1963 }
1964
1965 static void nfs4_reset_all_state(struct nfs_client *clp)
1966 {
1967         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1968                 set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
1969                 clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
1970                 nfs4_state_start_reclaim_nograce(clp);
1971                 dprintk("%s: scheduling reset of all state for server %s!\n",
1972                                 __func__, clp->cl_hostname);
1973                 nfs4_schedule_state_manager(clp);
1974         }
1975 }
1976
1977 static void nfs41_handle_server_reboot(struct nfs_client *clp)
1978 {
1979         if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
1980                 nfs4_state_start_reclaim_reboot(clp);
1981                 dprintk("%s: server %s rebooted!\n", __func__,
1982                                 clp->cl_hostname);
1983                 nfs4_schedule_state_manager(clp);
1984         }
1985 }
1986
1987 static void nfs41_handle_state_revoked(struct nfs_client *clp)
1988 {
1989         nfs4_reset_all_state(clp);
1990         dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
1991 }
1992
1993 static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
1994 {
1995         /* This will need to handle layouts too */
1996         nfs_expire_all_delegations(clp);
1997         dprintk("%s: Recallable state revoked on server %s!\n", __func__,
1998                         clp->cl_hostname);
1999 }
2000
2001 static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
2002 {
2003         nfs_expire_all_delegations(clp);
2004         if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
2005                 nfs4_schedule_state_manager(clp);
2006         dprintk("%s: server %s declared a backchannel fault\n", __func__,
2007                         clp->cl_hostname);
2008 }
2009
2010 static void nfs41_handle_cb_path_down(struct nfs_client *clp)
2011 {
2012         if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2013                 &clp->cl_state) == 0)
2014                 nfs4_schedule_state_manager(clp);
2015 }
2016
2017 void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
2018 {
2019         if (!flags)
2020                 return;
2021
2022         dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
2023                 __func__, clp->cl_hostname, clp->cl_clientid, flags);
2024
2025         if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
2026                 nfs41_handle_server_reboot(clp);
2027         if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
2028                             SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
2029                             SEQ4_STATUS_ADMIN_STATE_REVOKED |
2030                             SEQ4_STATUS_LEASE_MOVED))
2031                 nfs41_handle_state_revoked(clp);
2032         if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
2033                 nfs41_handle_recallable_state_revoked(clp);
2034         if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
2035                 nfs41_handle_backchannel_fault(clp);
2036         else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
2037                                 SEQ4_STATUS_CB_PATH_DOWN_SESSION))
2038                 nfs41_handle_cb_path_down(clp);
2039 }
2040
2041 static int nfs4_reset_session(struct nfs_client *clp)
2042 {
2043         struct rpc_cred *cred;
2044         int status;
2045
2046         if (!nfs4_has_session(clp))
2047                 return 0;
2048         nfs4_begin_drain_session(clp);
2049         cred = nfs4_get_exchange_id_cred(clp);
2050         status = nfs4_proc_destroy_session(clp->cl_session, cred);
2051         switch (status) {
2052         case 0:
2053         case -NFS4ERR_BADSESSION:
2054         case -NFS4ERR_DEADSESSION:
2055                 break;
2056         case -NFS4ERR_BACK_CHAN_BUSY:
2057         case -NFS4ERR_DELAY:
2058                 set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
2059                 status = 0;
2060                 ssleep(1);
2061                 goto out;
2062         default:
2063                 status = nfs4_recovery_handle_error(clp, status);
2064                 goto out;
2065         }
2066
2067         memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
2068         status = nfs4_proc_create_session(clp, cred);
2069         if (status) {
2070                 dprintk("%s: session reset failed with status %d for server %s!\n",
2071                         __func__, status, clp->cl_hostname);
2072                 status = nfs4_handle_reclaim_lease_error(clp, status);
2073                 goto out;
2074         }
2075         nfs41_finish_session_reset(clp);
2076         dprintk("%s: session reset was successful for server %s!\n",
2077                         __func__, clp->cl_hostname);
2078 out:
2079         if (cred)
2080                 put_rpccred(cred);
2081         return status;
2082 }
2083
2084 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2085 {
2086         struct rpc_cred *cred;
2087         int ret;
2088
2089         if (!nfs4_has_session(clp))
2090                 return 0;
2091         nfs4_begin_drain_session(clp);
2092         cred = nfs4_get_exchange_id_cred(clp);
2093         ret = nfs4_proc_bind_conn_to_session(clp, cred);
2094         if (cred)
2095                 put_rpccred(cred);
2096         clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2097         switch (ret) {
2098         case 0:
2099                 dprintk("%s: bind_conn_to_session was successful for server %s!\n",
2100                         __func__, clp->cl_hostname);
2101                 break;
2102         case -NFS4ERR_DELAY:
2103                 ssleep(1);
2104                 set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
2105                 break;
2106         default:
2107                 return nfs4_recovery_handle_error(clp, ret);
2108         }
2109         return 0;
2110 }
2111 #else /* CONFIG_NFS_V4_1 */
2112 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
2113 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
2114
2115 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
2116 {
2117         return 0;
2118 }
2119 #endif /* CONFIG_NFS_V4_1 */
2120
2121 static void nfs4_state_manager(struct nfs_client *clp)
2122 {
2123         int status = 0;
2124         const char *section = "", *section_sep = "";
2125
2126         /* Ensure exclusive access to NFSv4 state */
2127         do {
2128                 if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
2129                         section = "purge state";
2130                         status = nfs4_purge_lease(clp);
2131                         if (status < 0)
2132                                 goto out_error;
2133                         continue;
2134                 }
2135
2136                 if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
2137                         section = "lease expired";
2138                         /* We're going to have to re-establish a clientid */
2139                         status = nfs4_reclaim_lease(clp);
2140                         if (status < 0)
2141                                 goto out_error;
2142                         continue;
2143                 }
2144
2145                 /* Initialize or reset the session */
2146                 if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) {
2147                         section = "reset session";
2148                         status = nfs4_reset_session(clp);
2149                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
2150                                 continue;
2151                         if (status < 0)
2152                                 goto out_error;
2153                 }
2154
2155                 /* Send BIND_CONN_TO_SESSION */
2156                 if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
2157                                 &clp->cl_state)) {
2158                         section = "bind conn to session";
2159                         status = nfs4_bind_conn_to_session(clp);
2160                         if (status < 0)
2161                                 goto out_error;
2162                         continue;
2163                 }
2164
2165                 if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
2166                         section = "check lease";
2167                         status = nfs4_check_lease(clp);
2168                         if (status < 0)
2169                                 goto out_error;
2170                         continue;
2171                 }
2172
2173                 /* First recover reboot state... */
2174                 if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
2175                         section = "reclaim reboot";
2176                         status = nfs4_do_reclaim(clp,
2177                                 clp->cl_mvops->reboot_recovery_ops);
2178                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
2179                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
2180                                 continue;
2181                         nfs4_state_end_reclaim_reboot(clp);
2182                         if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
2183                                 continue;
2184                         if (status < 0)
2185                                 goto out_error;
2186                 }
2187
2188                 /* Now recover expired state... */
2189                 if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
2190                         section = "reclaim nograce";
2191                         status = nfs4_do_reclaim(clp,
2192                                 clp->cl_mvops->nograce_recovery_ops);
2193                         if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
2194                             test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
2195                             test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
2196                                 continue;
2197                         if (status < 0)
2198                                 goto out_error;
2199                 }
2200
2201                 nfs4_end_drain_session(clp);
2202                 if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
2203                         nfs_client_return_marked_delegations(clp);
2204                         continue;
2205                 }
2206
2207                 nfs4_clear_state_manager_bit(clp);
2208                 /* Did we race with an attempt to give us more work? */
2209                 if (clp->cl_state == 0)
2210                         break;
2211                 if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
2212                         break;
2213         } while (atomic_read(&clp->cl_count) > 1);
2214         return;
2215 out_error:
2216         if (strlen(section))
2217                 section_sep = ": ";
2218         pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s"
2219                         " with error %d\n", section_sep, section,
2220                         clp->cl_hostname, -status);
2221         ssleep(1);
2222         nfs4_end_drain_session(clp);
2223         nfs4_clear_state_manager_bit(clp);
2224 }
2225
2226 static int nfs4_run_state_manager(void *ptr)
2227 {
2228         struct nfs_client *clp = ptr;
2229
2230         allow_signal(SIGKILL);
2231         nfs4_state_manager(clp);
2232         nfs_put_client(clp);
2233         module_put_and_exit(0);
2234         return 0;
2235 }
2236
2237 /*
2238  * Local variables:
2239  *  c-basic-offset: 8
2240  * End:
2241  */