xref: /linux/fs/nfs/nfs4state.c (revision af901ca181d92aac3a7dc265144a9081a86d8f39)
1 /*
2  *  fs/nfs/nfs4state.c
3  *
4  *  Client-side XDR for NFSv4.
5  *
6  *  Copyright (c) 2002 The Regents of the University of Michigan.
7  *  All rights reserved.
8  *
9  *  Kendrick Smith <kmsmith@umich.edu>
10  *
11  *  Redistribution and use in source and binary forms, with or without
12  *  modification, are permitted provided that the following conditions
13  *  are met:
14  *
15  *  1. Redistributions of source code must retain the above copyright
16  *     notice, this list of conditions and the following disclaimer.
17  *  2. Redistributions in binary form must reproduce the above copyright
18  *     notice, this list of conditions and the following disclaimer in the
19  *     documentation and/or other materials provided with the distribution.
20  *  3. Neither the name of the University nor the names of its
21  *     contributors may be used to endorse or promote products derived
22  *     from this software without specific prior written permission.
23  *
24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35  *
36  * Implementation of the NFSv4 state model.  For the time being,
37  * this is minimal, but will be made much more complex in a
38  * subsequent patch.
39  */
40 
41 #include <linux/kernel.h>
42 #include <linux/slab.h>
43 #include <linux/smp_lock.h>
44 #include <linux/nfs_fs.h>
45 #include <linux/nfs_idmap.h>
46 #include <linux/kthread.h>
47 #include <linux/module.h>
48 #include <linux/random.h>
49 #include <linux/workqueue.h>
50 #include <linux/bitops.h>
51 
52 #include "nfs4_fs.h"
53 #include "callback.h"
54 #include "delegation.h"
55 #include "internal.h"
56 
57 #define OPENOWNER_POOL_SIZE	8
58 
59 const nfs4_stateid zero_stateid;
60 
61 static LIST_HEAD(nfs4_clientid_list);
62 
63 int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
64 {
65 	unsigned short port;
66 	int status;
67 
68 	port = nfs_callback_tcpport;
69 	if (clp->cl_addr.ss_family == AF_INET6)
70 		port = nfs_callback_tcpport6;
71 
72 	status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred);
73 	if (status == 0)
74 		status = nfs4_proc_setclientid_confirm(clp, cred);
75 	if (status == 0)
76 		nfs4_schedule_state_renewal(clp);
77 	return status;
78 }
79 
80 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
81 {
82 	struct rpc_cred *cred = NULL;
83 
84 	if (clp->cl_machine_cred != NULL)
85 		cred = get_rpccred(clp->cl_machine_cred);
86 	return cred;
87 }
88 
89 static void nfs4_clear_machine_cred(struct nfs_client *clp)
90 {
91 	struct rpc_cred *cred;
92 
93 	spin_lock(&clp->cl_lock);
94 	cred = clp->cl_machine_cred;
95 	clp->cl_machine_cred = NULL;
96 	spin_unlock(&clp->cl_lock);
97 	if (cred != NULL)
98 		put_rpccred(cred);
99 }
100 
101 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
102 {
103 	struct nfs4_state_owner *sp;
104 	struct rb_node *pos;
105 	struct rpc_cred *cred = NULL;
106 
107 	for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
108 		sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
109 		if (list_empty(&sp->so_states))
110 			continue;
111 		cred = get_rpccred(sp->so_cred);
112 		break;
113 	}
114 	return cred;
115 }
116 
117 #if defined(CONFIG_NFS_V4_1)
118 
119 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
120 {
121 	struct rpc_cred *cred;
122 
123 	spin_lock(&clp->cl_lock);
124 	cred = nfs4_get_machine_cred_locked(clp);
125 	spin_unlock(&clp->cl_lock);
126 	return cred;
127 }
128 
129 #endif /* CONFIG_NFS_V4_1 */
130 
131 struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
132 {
133 	struct nfs4_state_owner *sp;
134 	struct rb_node *pos;
135 	struct rpc_cred *cred;
136 
137 	spin_lock(&clp->cl_lock);
138 	cred = nfs4_get_machine_cred_locked(clp);
139 	if (cred != NULL)
140 		goto out;
141 	pos = rb_first(&clp->cl_state_owners);
142 	if (pos != NULL) {
143 		sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
144 		cred = get_rpccred(sp->so_cred);
145 	}
146 out:
147 	spin_unlock(&clp->cl_lock);
148 	return cred;
149 }
150 
151 static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
152 		__u64 minval, int maxbits)
153 {
154 	struct rb_node **p, *parent;
155 	struct nfs_unique_id *pos;
156 	__u64 mask = ~0ULL;
157 
158 	if (maxbits < 64)
159 		mask = (1ULL << maxbits) - 1ULL;
160 
161 	/* Ensure distribution is more or less flat */
162 	get_random_bytes(&new->id, sizeof(new->id));
163 	new->id &= mask;
164 	if (new->id < minval)
165 		new->id += minval;
166 retry:
167 	p = &root->rb_node;
168 	parent = NULL;
169 
170 	while (*p != NULL) {
171 		parent = *p;
172 		pos = rb_entry(parent, struct nfs_unique_id, rb_node);
173 
174 		if (new->id < pos->id)
175 			p = &(*p)->rb_left;
176 		else if (new->id > pos->id)
177 			p = &(*p)->rb_right;
178 		else
179 			goto id_exists;
180 	}
181 	rb_link_node(&new->rb_node, parent, p);
182 	rb_insert_color(&new->rb_node, root);
183 	return;
184 id_exists:
185 	for (;;) {
186 		new->id++;
187 		if (new->id < minval || (new->id & mask) != new->id) {
188 			new->id = minval;
189 			break;
190 		}
191 		parent = rb_next(parent);
192 		if (parent == NULL)
193 			break;
194 		pos = rb_entry(parent, struct nfs_unique_id, rb_node);
195 		if (new->id < pos->id)
196 			break;
197 	}
198 	goto retry;
199 }
200 
201 static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
202 {
203 	rb_erase(&id->rb_node, root);
204 }
205 
206 static struct nfs4_state_owner *
207 nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
208 {
209 	struct nfs_client *clp = server->nfs_client;
210 	struct rb_node **p = &clp->cl_state_owners.rb_node,
211 		       *parent = NULL;
212 	struct nfs4_state_owner *sp, *res = NULL;
213 
214 	while (*p != NULL) {
215 		parent = *p;
216 		sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
217 
218 		if (server < sp->so_server) {
219 			p = &parent->rb_left;
220 			continue;
221 		}
222 		if (server > sp->so_server) {
223 			p = &parent->rb_right;
224 			continue;
225 		}
226 		if (cred < sp->so_cred)
227 			p = &parent->rb_left;
228 		else if (cred > sp->so_cred)
229 			p = &parent->rb_right;
230 		else {
231 			atomic_inc(&sp->so_count);
232 			res = sp;
233 			break;
234 		}
235 	}
236 	return res;
237 }
238 
239 static struct nfs4_state_owner *
240 nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
241 {
242 	struct rb_node **p = &clp->cl_state_owners.rb_node,
243 		       *parent = NULL;
244 	struct nfs4_state_owner *sp;
245 
246 	while (*p != NULL) {
247 		parent = *p;
248 		sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
249 
250 		if (new->so_server < sp->so_server) {
251 			p = &parent->rb_left;
252 			continue;
253 		}
254 		if (new->so_server > sp->so_server) {
255 			p = &parent->rb_right;
256 			continue;
257 		}
258 		if (new->so_cred < sp->so_cred)
259 			p = &parent->rb_left;
260 		else if (new->so_cred > sp->so_cred)
261 			p = &parent->rb_right;
262 		else {
263 			atomic_inc(&sp->so_count);
264 			return sp;
265 		}
266 	}
267 	nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
268 	rb_link_node(&new->so_client_node, parent, p);
269 	rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
270 	return new;
271 }
272 
273 static void
274 nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
275 {
276 	if (!RB_EMPTY_NODE(&sp->so_client_node))
277 		rb_erase(&sp->so_client_node, &clp->cl_state_owners);
278 	nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
279 }
280 
281 /*
282  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
283  * create a new state_owner.
284  *
285  */
286 static struct nfs4_state_owner *
287 nfs4_alloc_state_owner(void)
288 {
289 	struct nfs4_state_owner *sp;
290 
291 	sp = kzalloc(sizeof(*sp),GFP_KERNEL);
292 	if (!sp)
293 		return NULL;
294 	spin_lock_init(&sp->so_lock);
295 	INIT_LIST_HEAD(&sp->so_states);
296 	INIT_LIST_HEAD(&sp->so_delegations);
297 	rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue");
298 	sp->so_seqid.sequence = &sp->so_sequence;
299 	spin_lock_init(&sp->so_sequence.lock);
300 	INIT_LIST_HEAD(&sp->so_sequence.list);
301 	atomic_set(&sp->so_count, 1);
302 	return sp;
303 }
304 
305 static void
306 nfs4_drop_state_owner(struct nfs4_state_owner *sp)
307 {
308 	if (!RB_EMPTY_NODE(&sp->so_client_node)) {
309 		struct nfs_client *clp = sp->so_client;
310 
311 		spin_lock(&clp->cl_lock);
312 		rb_erase(&sp->so_client_node, &clp->cl_state_owners);
313 		RB_CLEAR_NODE(&sp->so_client_node);
314 		spin_unlock(&clp->cl_lock);
315 	}
316 }
317 
318 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
319 {
320 	struct nfs_client *clp = server->nfs_client;
321 	struct nfs4_state_owner *sp, *new;
322 
323 	spin_lock(&clp->cl_lock);
324 	sp = nfs4_find_state_owner(server, cred);
325 	spin_unlock(&clp->cl_lock);
326 	if (sp != NULL)
327 		return sp;
328 	new = nfs4_alloc_state_owner();
329 	if (new == NULL)
330 		return NULL;
331 	new->so_client = clp;
332 	new->so_server = server;
333 	new->so_cred = cred;
334 	spin_lock(&clp->cl_lock);
335 	sp = nfs4_insert_state_owner(clp, new);
336 	spin_unlock(&clp->cl_lock);
337 	if (sp == new)
338 		get_rpccred(cred);
339 	else {
340 		rpc_destroy_wait_queue(&new->so_sequence.wait);
341 		kfree(new);
342 	}
343 	return sp;
344 }
345 
346 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
347 {
348 	struct nfs_client *clp = sp->so_client;
349 	struct rpc_cred *cred = sp->so_cred;
350 
351 	if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
352 		return;
353 	nfs4_remove_state_owner(clp, sp);
354 	spin_unlock(&clp->cl_lock);
355 	rpc_destroy_wait_queue(&sp->so_sequence.wait);
356 	put_rpccred(cred);
357 	kfree(sp);
358 }
359 
360 static struct nfs4_state *
361 nfs4_alloc_open_state(void)
362 {
363 	struct nfs4_state *state;
364 
365 	state = kzalloc(sizeof(*state), GFP_KERNEL);
366 	if (!state)
367 		return NULL;
368 	atomic_set(&state->count, 1);
369 	INIT_LIST_HEAD(&state->lock_states);
370 	spin_lock_init(&state->state_lock);
371 	seqlock_init(&state->seqlock);
372 	return state;
373 }
374 
375 void
376 nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
377 {
378 	if (state->state == fmode)
379 		return;
380 	/* NB! List reordering - see the reclaim code for why.  */
381 	if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
382 		if (fmode & FMODE_WRITE)
383 			list_move(&state->open_states, &state->owner->so_states);
384 		else
385 			list_move_tail(&state->open_states, &state->owner->so_states);
386 	}
387 	state->state = fmode;
388 }
389 
390 static struct nfs4_state *
391 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
392 {
393 	struct nfs_inode *nfsi = NFS_I(inode);
394 	struct nfs4_state *state;
395 
396 	list_for_each_entry(state, &nfsi->open_states, inode_states) {
397 		if (state->owner != owner)
398 			continue;
399 		if (atomic_inc_not_zero(&state->count))
400 			return state;
401 	}
402 	return NULL;
403 }
404 
405 static void
406 nfs4_free_open_state(struct nfs4_state *state)
407 {
408 	kfree(state);
409 }
410 
411 struct nfs4_state *
412 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
413 {
414 	struct nfs4_state *state, *new;
415 	struct nfs_inode *nfsi = NFS_I(inode);
416 
417 	spin_lock(&inode->i_lock);
418 	state = __nfs4_find_state_byowner(inode, owner);
419 	spin_unlock(&inode->i_lock);
420 	if (state)
421 		goto out;
422 	new = nfs4_alloc_open_state();
423 	spin_lock(&owner->so_lock);
424 	spin_lock(&inode->i_lock);
425 	state = __nfs4_find_state_byowner(inode, owner);
426 	if (state == NULL && new != NULL) {
427 		state = new;
428 		state->owner = owner;
429 		atomic_inc(&owner->so_count);
430 		list_add(&state->inode_states, &nfsi->open_states);
431 		state->inode = igrab(inode);
432 		spin_unlock(&inode->i_lock);
433 		/* Note: The reclaim code dictates that we add stateless
434 		 * and read-only stateids to the end of the list */
435 		list_add_tail(&state->open_states, &owner->so_states);
436 		spin_unlock(&owner->so_lock);
437 	} else {
438 		spin_unlock(&inode->i_lock);
439 		spin_unlock(&owner->so_lock);
440 		if (new)
441 			nfs4_free_open_state(new);
442 	}
443 out:
444 	return state;
445 }
446 
447 void nfs4_put_open_state(struct nfs4_state *state)
448 {
449 	struct inode *inode = state->inode;
450 	struct nfs4_state_owner *owner = state->owner;
451 
452 	if (!atomic_dec_and_lock(&state->count, &owner->so_lock))
453 		return;
454 	spin_lock(&inode->i_lock);
455 	list_del(&state->inode_states);
456 	list_del(&state->open_states);
457 	spin_unlock(&inode->i_lock);
458 	spin_unlock(&owner->so_lock);
459 	iput(inode);
460 	nfs4_free_open_state(state);
461 	nfs4_put_state_owner(owner);
462 }
463 
464 /*
465  * Close the current file.
466  */
467 static void __nfs4_close(struct path *path, struct nfs4_state *state, fmode_t fmode, int wait)
468 {
469 	struct nfs4_state_owner *owner = state->owner;
470 	int call_close = 0;
471 	fmode_t newstate;
472 
473 	atomic_inc(&owner->so_count);
474 	/* Protect against nfs4_find_state() */
475 	spin_lock(&owner->so_lock);
476 	switch (fmode & (FMODE_READ | FMODE_WRITE)) {
477 		case FMODE_READ:
478 			state->n_rdonly--;
479 			break;
480 		case FMODE_WRITE:
481 			state->n_wronly--;
482 			break;
483 		case FMODE_READ|FMODE_WRITE:
484 			state->n_rdwr--;
485 	}
486 	newstate = FMODE_READ|FMODE_WRITE;
487 	if (state->n_rdwr == 0) {
488 		if (state->n_rdonly == 0) {
489 			newstate &= ~FMODE_READ;
490 			call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
491 			call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
492 		}
493 		if (state->n_wronly == 0) {
494 			newstate &= ~FMODE_WRITE;
495 			call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
496 			call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
497 		}
498 		if (newstate == 0)
499 			clear_bit(NFS_DELEGATED_STATE, &state->flags);
500 	}
501 	nfs4_state_set_mode_locked(state, newstate);
502 	spin_unlock(&owner->so_lock);
503 
504 	if (!call_close) {
505 		nfs4_put_open_state(state);
506 		nfs4_put_state_owner(owner);
507 	} else
508 		nfs4_do_close(path, state, wait);
509 }
510 
511 void nfs4_close_state(struct path *path, struct nfs4_state *state, fmode_t fmode)
512 {
513 	__nfs4_close(path, state, fmode, 0);
514 }
515 
516 void nfs4_close_sync(struct path *path, struct nfs4_state *state, fmode_t fmode)
517 {
518 	__nfs4_close(path, state, fmode, 1);
519 }
520 
521 /*
522  * Search the state->lock_states for an existing lock_owner
523  * that is compatible with current->files
524  */
525 static struct nfs4_lock_state *
526 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
527 {
528 	struct nfs4_lock_state *pos;
529 	list_for_each_entry(pos, &state->lock_states, ls_locks) {
530 		if (pos->ls_owner != fl_owner)
531 			continue;
532 		atomic_inc(&pos->ls_count);
533 		return pos;
534 	}
535 	return NULL;
536 }
537 
538 /*
539  * Return a compatible lock_state. If no initialized lock_state structure
540  * exists, return an uninitialized one.
541  *
542  */
543 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
544 {
545 	struct nfs4_lock_state *lsp;
546 	struct nfs_client *clp = state->owner->so_client;
547 
548 	lsp = kzalloc(sizeof(*lsp), GFP_KERNEL);
549 	if (lsp == NULL)
550 		return NULL;
551 	rpc_init_wait_queue(&lsp->ls_sequence.wait, "lock_seqid_waitqueue");
552 	spin_lock_init(&lsp->ls_sequence.lock);
553 	INIT_LIST_HEAD(&lsp->ls_sequence.list);
554 	lsp->ls_seqid.sequence = &lsp->ls_sequence;
555 	atomic_set(&lsp->ls_count, 1);
556 	lsp->ls_state = state;
557 	lsp->ls_owner = fl_owner;
558 	spin_lock(&clp->cl_lock);
559 	nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
560 	spin_unlock(&clp->cl_lock);
561 	INIT_LIST_HEAD(&lsp->ls_locks);
562 	return lsp;
563 }
564 
565 static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
566 {
567 	struct nfs_client *clp = lsp->ls_state->owner->so_client;
568 
569 	spin_lock(&clp->cl_lock);
570 	nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
571 	spin_unlock(&clp->cl_lock);
572 	rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
573 	kfree(lsp);
574 }
575 
576 /*
577  * Return a compatible lock_state. If no initialized lock_state structure
578  * exists, return an uninitialized one.
579  *
580  */
581 static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
582 {
583 	struct nfs4_lock_state *lsp, *new = NULL;
584 
585 	for(;;) {
586 		spin_lock(&state->state_lock);
587 		lsp = __nfs4_find_lock_state(state, owner);
588 		if (lsp != NULL)
589 			break;
590 		if (new != NULL) {
591 			list_add(&new->ls_locks, &state->lock_states);
592 			set_bit(LK_STATE_IN_USE, &state->flags);
593 			lsp = new;
594 			new = NULL;
595 			break;
596 		}
597 		spin_unlock(&state->state_lock);
598 		new = nfs4_alloc_lock_state(state, owner);
599 		if (new == NULL)
600 			return NULL;
601 	}
602 	spin_unlock(&state->state_lock);
603 	if (new != NULL)
604 		nfs4_free_lock_state(new);
605 	return lsp;
606 }
607 
608 /*
609  * Release reference to lock_state, and free it if we see that
610  * it is no longer in use
611  */
612 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
613 {
614 	struct nfs4_state *state;
615 
616 	if (lsp == NULL)
617 		return;
618 	state = lsp->ls_state;
619 	if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock))
620 		return;
621 	list_del(&lsp->ls_locks);
622 	if (list_empty(&state->lock_states))
623 		clear_bit(LK_STATE_IN_USE, &state->flags);
624 	spin_unlock(&state->state_lock);
625 	nfs4_free_lock_state(lsp);
626 }
627 
628 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
629 {
630 	struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
631 
632 	dst->fl_u.nfs4_fl.owner = lsp;
633 	atomic_inc(&lsp->ls_count);
634 }
635 
636 static void nfs4_fl_release_lock(struct file_lock *fl)
637 {
638 	nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
639 }
640 
641 static const struct file_lock_operations nfs4_fl_lock_ops = {
642 	.fl_copy_lock = nfs4_fl_copy_lock,
643 	.fl_release_private = nfs4_fl_release_lock,
644 };
645 
646 int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
647 {
648 	struct nfs4_lock_state *lsp;
649 
650 	if (fl->fl_ops != NULL)
651 		return 0;
652 	lsp = nfs4_get_lock_state(state, fl->fl_owner);
653 	if (lsp == NULL)
654 		return -ENOMEM;
655 	fl->fl_u.nfs4_fl.owner = lsp;
656 	fl->fl_ops = &nfs4_fl_lock_ops;
657 	return 0;
658 }
659 
660 /*
661  * Byte-range lock aware utility to initialize the stateid of read/write
662  * requests.
663  */
664 void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
665 {
666 	struct nfs4_lock_state *lsp;
667 	int seq;
668 
669 	do {
670 		seq = read_seqbegin(&state->seqlock);
671 		memcpy(dst, &state->stateid, sizeof(*dst));
672 	} while (read_seqretry(&state->seqlock, seq));
673 	if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
674 		return;
675 
676 	spin_lock(&state->state_lock);
677 	lsp = __nfs4_find_lock_state(state, fl_owner);
678 	if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
679 		memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
680 	spin_unlock(&state->state_lock);
681 	nfs4_put_lock_state(lsp);
682 }
683 
684 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
685 {
686 	struct nfs_seqid *new;
687 
688 	new = kmalloc(sizeof(*new), GFP_KERNEL);
689 	if (new != NULL) {
690 		new->sequence = counter;
691 		INIT_LIST_HEAD(&new->list);
692 	}
693 	return new;
694 }
695 
696 void nfs_free_seqid(struct nfs_seqid *seqid)
697 {
698 	if (!list_empty(&seqid->list)) {
699 		struct rpc_sequence *sequence = seqid->sequence->sequence;
700 
701 		spin_lock(&sequence->lock);
702 		list_del(&seqid->list);
703 		spin_unlock(&sequence->lock);
704 		rpc_wake_up(&sequence->wait);
705 	}
706 	kfree(seqid);
707 }
708 
709 /*
710  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
711  * failed with a seqid incrementing error -
712  * see comments nfs_fs.h:seqid_mutating_error()
713  */
714 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
715 {
716 	BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
717 	switch (status) {
718 		case 0:
719 			break;
720 		case -NFS4ERR_BAD_SEQID:
721 			if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
722 				return;
723 			printk(KERN_WARNING "NFS: v4 server returned a bad"
724 					" sequence-id error on an"
725 					" unconfirmed sequence %p!\n",
726 					seqid->sequence);
727 		case -NFS4ERR_STALE_CLIENTID:
728 		case -NFS4ERR_STALE_STATEID:
729 		case -NFS4ERR_BAD_STATEID:
730 		case -NFS4ERR_BADXDR:
731 		case -NFS4ERR_RESOURCE:
732 		case -NFS4ERR_NOFILEHANDLE:
733 			/* Non-seqid mutating errors */
734 			return;
735 	};
736 	/*
737 	 * Note: no locking needed as we are guaranteed to be first
738 	 * on the sequence list
739 	 */
740 	seqid->sequence->counter++;
741 }
742 
743 void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
744 {
745 	struct nfs4_state_owner *sp = container_of(seqid->sequence,
746 					struct nfs4_state_owner, so_seqid);
747 	struct nfs_server *server = sp->so_server;
748 
749 	if (status == -NFS4ERR_BAD_SEQID)
750 		nfs4_drop_state_owner(sp);
751 	if (!nfs4_has_session(server->nfs_client))
752 		nfs_increment_seqid(status, seqid);
753 }
754 
755 /*
756  * Increment the seqid if the LOCK/LOCKU succeeded, or
757  * failed with a seqid incrementing error -
758  * see comments nfs_fs.h:seqid_mutating_error()
759  */
760 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
761 {
762 	nfs_increment_seqid(status, seqid);
763 }
764 
765 int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
766 {
767 	struct rpc_sequence *sequence = seqid->sequence->sequence;
768 	int status = 0;
769 
770 	spin_lock(&sequence->lock);
771 	if (list_empty(&seqid->list))
772 		list_add_tail(&seqid->list, &sequence->list);
773 	if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
774 		goto unlock;
775 	rpc_sleep_on(&sequence->wait, task, NULL);
776 	status = -EAGAIN;
777 unlock:
778 	spin_unlock(&sequence->lock);
779 	return status;
780 }
781 
782 static int nfs4_run_state_manager(void *);
783 
784 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
785 {
786 	smp_mb__before_clear_bit();
787 	clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
788 	smp_mb__after_clear_bit();
789 	wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
790 	rpc_wake_up(&clp->cl_rpcwaitq);
791 }
792 
793 /*
794  * Schedule the nfs_client asynchronous state management routine
795  */
796 void nfs4_schedule_state_manager(struct nfs_client *clp)
797 {
798 	struct task_struct *task;
799 
800 	if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
801 		return;
802 	__module_get(THIS_MODULE);
803 	atomic_inc(&clp->cl_count);
804 	task = kthread_run(nfs4_run_state_manager, clp, "%s-manager",
805 				rpc_peeraddr2str(clp->cl_rpcclient,
806 							RPC_DISPLAY_ADDR));
807 	if (!IS_ERR(task))
808 		return;
809 	nfs4_clear_state_manager_bit(clp);
810 	nfs_put_client(clp);
811 	module_put(THIS_MODULE);
812 }
813 
814 /*
815  * Schedule a state recovery attempt
816  */
817 void nfs4_schedule_state_recovery(struct nfs_client *clp)
818 {
819 	if (!clp)
820 		return;
821 	if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
822 		set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
823 	nfs4_schedule_state_manager(clp);
824 }
825 
826 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
827 {
828 
829 	set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
830 	/* Don't recover state that expired before the reboot */
831 	if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
832 		clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
833 		return 0;
834 	}
835 	set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
836 	set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
837 	return 1;
838 }
839 
840 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
841 {
842 	set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
843 	clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
844 	set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
845 	set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
846 	return 1;
847 }
848 
849 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
850 {
851 	struct inode *inode = state->inode;
852 	struct nfs_inode *nfsi = NFS_I(inode);
853 	struct file_lock *fl;
854 	int status = 0;
855 
856 	if (inode->i_flock == NULL)
857 		return 0;
858 
859 	/* Guard against delegation returns and new lock/unlock calls */
860 	down_write(&nfsi->rwsem);
861 	/* Protect inode->i_flock using the BKL */
862 	lock_kernel();
863 	for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
864 		if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
865 			continue;
866 		if (nfs_file_open_context(fl->fl_file)->state != state)
867 			continue;
868 		unlock_kernel();
869 		status = ops->recover_lock(state, fl);
870 		switch (status) {
871 			case 0:
872 				break;
873 			case -ESTALE:
874 			case -NFS4ERR_ADMIN_REVOKED:
875 			case -NFS4ERR_STALE_STATEID:
876 			case -NFS4ERR_BAD_STATEID:
877 			case -NFS4ERR_EXPIRED:
878 			case -NFS4ERR_NO_GRACE:
879 			case -NFS4ERR_STALE_CLIENTID:
880 				goto out;
881 			default:
882 				printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
883 						__func__, status);
884 			case -ENOMEM:
885 			case -NFS4ERR_DENIED:
886 			case -NFS4ERR_RECLAIM_BAD:
887 			case -NFS4ERR_RECLAIM_CONFLICT:
888 				/* kill_proc(fl->fl_pid, SIGLOST, 1); */
889 				status = 0;
890 		}
891 		lock_kernel();
892 	}
893 	unlock_kernel();
894 out:
895 	up_write(&nfsi->rwsem);
896 	return status;
897 }
898 
899 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
900 {
901 	struct nfs4_state *state;
902 	struct nfs4_lock_state *lock;
903 	int status = 0;
904 
905 	/* Note: we rely on the sp->so_states list being ordered
906 	 * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
907 	 * states first.
908 	 * This is needed to ensure that the server won't give us any
909 	 * read delegations that we have to return if, say, we are
910 	 * recovering after a network partition or a reboot from a
911 	 * server that doesn't support a grace period.
912 	 */
913 restart:
914 	spin_lock(&sp->so_lock);
915 	list_for_each_entry(state, &sp->so_states, open_states) {
916 		if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
917 			continue;
918 		if (state->state == 0)
919 			continue;
920 		atomic_inc(&state->count);
921 		spin_unlock(&sp->so_lock);
922 		status = ops->recover_open(sp, state);
923 		if (status >= 0) {
924 			status = nfs4_reclaim_locks(state, ops);
925 			if (status >= 0) {
926 				list_for_each_entry(lock, &state->lock_states, ls_locks) {
927 					if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
928 						printk("%s: Lock reclaim failed!\n",
929 							__func__);
930 				}
931 				nfs4_put_open_state(state);
932 				goto restart;
933 			}
934 		}
935 		switch (status) {
936 			default:
937 				printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
938 						__func__, status);
939 			case -ENOENT:
940 			case -ENOMEM:
941 			case -ESTALE:
942 				/*
943 				 * Open state on this file cannot be recovered
944 				 * All we can do is revert to using the zero stateid.
945 				 */
946 				memset(state->stateid.data, 0,
947 					sizeof(state->stateid.data));
948 				/* Mark the file as being 'closed' */
949 				state->state = 0;
950 				break;
951 			case -NFS4ERR_ADMIN_REVOKED:
952 			case -NFS4ERR_STALE_STATEID:
953 			case -NFS4ERR_BAD_STATEID:
954 			case -NFS4ERR_RECLAIM_BAD:
955 			case -NFS4ERR_RECLAIM_CONFLICT:
956 				nfs4_state_mark_reclaim_nograce(sp->so_client, state);
957 				break;
958 			case -NFS4ERR_EXPIRED:
959 			case -NFS4ERR_NO_GRACE:
960 				nfs4_state_mark_reclaim_nograce(sp->so_client, state);
961 			case -NFS4ERR_STALE_CLIENTID:
962 				goto out_err;
963 		}
964 		nfs4_put_open_state(state);
965 		goto restart;
966 	}
967 	spin_unlock(&sp->so_lock);
968 	return 0;
969 out_err:
970 	nfs4_put_open_state(state);
971 	return status;
972 }
973 
974 static void nfs4_clear_open_state(struct nfs4_state *state)
975 {
976 	struct nfs4_lock_state *lock;
977 
978 	clear_bit(NFS_DELEGATED_STATE, &state->flags);
979 	clear_bit(NFS_O_RDONLY_STATE, &state->flags);
980 	clear_bit(NFS_O_WRONLY_STATE, &state->flags);
981 	clear_bit(NFS_O_RDWR_STATE, &state->flags);
982 	list_for_each_entry(lock, &state->lock_states, ls_locks) {
983 		lock->ls_seqid.flags = 0;
984 		lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
985 	}
986 }
987 
988 static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
989 {
990 	struct nfs4_state_owner *sp;
991 	struct rb_node *pos;
992 	struct nfs4_state *state;
993 
994 	/* Reset all sequence ids to zero */
995 	for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
996 		sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
997 		sp->so_seqid.flags = 0;
998 		spin_lock(&sp->so_lock);
999 		list_for_each_entry(state, &sp->so_states, open_states) {
1000 			if (mark_reclaim(clp, state))
1001 				nfs4_clear_open_state(state);
1002 		}
1003 		spin_unlock(&sp->so_lock);
1004 	}
1005 }
1006 
1007 static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
1008 {
1009 	/* Mark all delegations for reclaim */
1010 	nfs_delegation_mark_reclaim(clp);
1011 	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
1012 }
1013 
1014 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
1015 {
1016 	struct nfs4_state_owner *sp;
1017 	struct rb_node *pos;
1018 	struct nfs4_state *state;
1019 
1020 	if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1021 		return;
1022 
1023 	for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1024 		sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1025 		spin_lock(&sp->so_lock);
1026 		list_for_each_entry(state, &sp->so_states, open_states) {
1027 			if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
1028 				continue;
1029 			nfs4_state_mark_reclaim_nograce(clp, state);
1030 		}
1031 		spin_unlock(&sp->so_lock);
1032 	}
1033 
1034 	nfs_delegation_reap_unclaimed(clp);
1035 }
1036 
1037 static void nfs_delegation_clear_all(struct nfs_client *clp)
1038 {
1039 	nfs_delegation_mark_reclaim(clp);
1040 	nfs_delegation_reap_unclaimed(clp);
1041 }
1042 
1043 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
1044 {
1045 	nfs_delegation_clear_all(clp);
1046 	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
1047 }
1048 
1049 static void nfs4_state_end_reclaim_nograce(struct nfs_client *clp)
1050 {
1051 	clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1052 }
1053 
1054 static void nfs4_recovery_handle_error(struct nfs_client *clp, int error)
1055 {
1056 	switch (error) {
1057 		case -NFS4ERR_CB_PATH_DOWN:
1058 			nfs_handle_cb_pathdown(clp);
1059 			break;
1060 		case -NFS4ERR_STALE_CLIENTID:
1061 		case -NFS4ERR_LEASE_MOVED:
1062 			set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1063 			nfs4_state_start_reclaim_reboot(clp);
1064 			break;
1065 		case -NFS4ERR_EXPIRED:
1066 			set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1067 			nfs4_state_start_reclaim_nograce(clp);
1068 		case -NFS4ERR_BADSESSION:
1069 		case -NFS4ERR_BADSLOT:
1070 		case -NFS4ERR_BAD_HIGH_SLOT:
1071 		case -NFS4ERR_DEADSESSION:
1072 		case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1073 		case -NFS4ERR_SEQ_FALSE_RETRY:
1074 		case -NFS4ERR_SEQ_MISORDERED:
1075 			set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1076 	}
1077 }
1078 
1079 static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
1080 {
1081 	struct rb_node *pos;
1082 	int status = 0;
1083 
1084 restart:
1085 	spin_lock(&clp->cl_lock);
1086 	for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
1087 		struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
1088 		if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
1089 			continue;
1090 		atomic_inc(&sp->so_count);
1091 		spin_unlock(&clp->cl_lock);
1092 		status = nfs4_reclaim_open_state(sp, ops);
1093 		if (status < 0) {
1094 			set_bit(ops->owner_flag_bit, &sp->so_flags);
1095 			nfs4_put_state_owner(sp);
1096 			nfs4_recovery_handle_error(clp, status);
1097 			return status;
1098 		}
1099 		nfs4_put_state_owner(sp);
1100 		goto restart;
1101 	}
1102 	spin_unlock(&clp->cl_lock);
1103 	return status;
1104 }
1105 
1106 static int nfs4_check_lease(struct nfs_client *clp)
1107 {
1108 	struct rpc_cred *cred;
1109 	struct nfs4_state_maintenance_ops *ops =
1110 		nfs4_state_renewal_ops[clp->cl_minorversion];
1111 	int status = -NFS4ERR_EXPIRED;
1112 
1113 	/* Is the client already known to have an expired lease? */
1114 	if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
1115 		return 0;
1116 	spin_lock(&clp->cl_lock);
1117 	cred = ops->get_state_renewal_cred_locked(clp);
1118 	spin_unlock(&clp->cl_lock);
1119 	if (cred == NULL) {
1120 		cred = nfs4_get_setclientid_cred(clp);
1121 		if (cred == NULL)
1122 			goto out;
1123 	}
1124 	status = ops->renew_lease(clp, cred);
1125 	put_rpccred(cred);
1126 out:
1127 	nfs4_recovery_handle_error(clp, status);
1128 	return status;
1129 }
1130 
1131 static int nfs4_reclaim_lease(struct nfs_client *clp)
1132 {
1133 	struct rpc_cred *cred;
1134 	struct nfs4_state_recovery_ops *ops =
1135 		nfs4_reboot_recovery_ops[clp->cl_minorversion];
1136 	int status = -ENOENT;
1137 
1138 	cred = ops->get_clid_cred(clp);
1139 	if (cred != NULL) {
1140 		status = ops->establish_clid(clp, cred);
1141 		put_rpccred(cred);
1142 		/* Handle case where the user hasn't set up machine creds */
1143 		if (status == -EACCES && cred == clp->cl_machine_cred) {
1144 			nfs4_clear_machine_cred(clp);
1145 			status = -EAGAIN;
1146 		}
1147 		if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
1148 			status = -EPROTONOSUPPORT;
1149 	}
1150 	return status;
1151 }
1152 
1153 #ifdef CONFIG_NFS_V4_1
1154 static void nfs4_session_recovery_handle_error(struct nfs_client *clp, int err)
1155 {
1156 	switch (err) {
1157 	case -NFS4ERR_STALE_CLIENTID:
1158 		set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1159 		set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1160 	}
1161 }
1162 
1163 static int nfs4_reset_session(struct nfs_client *clp)
1164 {
1165 	int status;
1166 
1167 	status = nfs4_proc_destroy_session(clp->cl_session);
1168 	if (status && status != -NFS4ERR_BADSESSION &&
1169 	    status != -NFS4ERR_DEADSESSION) {
1170 		nfs4_session_recovery_handle_error(clp, status);
1171 		goto out;
1172 	}
1173 
1174 	memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
1175 	status = nfs4_proc_create_session(clp, 1);
1176 	if (status)
1177 		nfs4_session_recovery_handle_error(clp, status);
1178 		/* fall through*/
1179 out:
1180 	/* Wake up the next rpc task even on error */
1181 	rpc_wake_up_next(&clp->cl_session->fc_slot_table.slot_tbl_waitq);
1182 	return status;
1183 }
1184 
1185 static int nfs4_initialize_session(struct nfs_client *clp)
1186 {
1187 	int status;
1188 
1189 	status = nfs4_proc_create_session(clp, 0);
1190 	if (!status) {
1191 		nfs_mark_client_ready(clp, NFS_CS_READY);
1192 	} else if (status == -NFS4ERR_STALE_CLIENTID) {
1193 		set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1194 		set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
1195 	} else {
1196 		nfs_mark_client_ready(clp, status);
1197 	}
1198 	return status;
1199 }
1200 #else /* CONFIG_NFS_V4_1 */
1201 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
1202 static int nfs4_initialize_session(struct nfs_client *clp) { return 0; }
1203 #endif /* CONFIG_NFS_V4_1 */
1204 
1205 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
1206  * on EXCHANGE_ID for v4.1
1207  */
1208 static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
1209 {
1210 	if (nfs4_has_session(clp)) {
1211 		switch (status) {
1212 		case -NFS4ERR_DELAY:
1213 		case -NFS4ERR_CLID_INUSE:
1214 		case -EAGAIN:
1215 			break;
1216 
1217 		case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
1218 					 * in nfs4_exchange_id */
1219 		default:
1220 			return;
1221 		}
1222 	}
1223 	set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
1224 }
1225 
1226 static void nfs4_state_manager(struct nfs_client *clp)
1227 {
1228 	int status = 0;
1229 
1230 	/* Ensure exclusive access to NFSv4 state */
1231 	for(;;) {
1232 		if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
1233 			/* We're going to have to re-establish a clientid */
1234 			status = nfs4_reclaim_lease(clp);
1235 			if (status) {
1236 				nfs4_set_lease_expired(clp, status);
1237 				if (status == -EAGAIN)
1238 					continue;
1239 				if (clp->cl_cons_state ==
1240 							NFS_CS_SESSION_INITING)
1241 					nfs_mark_client_ready(clp, status);
1242 				goto out_error;
1243 			}
1244 			clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
1245 		}
1246 
1247 		if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
1248 			status = nfs4_check_lease(clp);
1249 			if (status != 0)
1250 				continue;
1251 		}
1252 		/* Initialize or reset the session */
1253 		if (test_and_clear_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state)
1254 		   && nfs4_has_session(clp)) {
1255 			if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
1256 				status = nfs4_initialize_session(clp);
1257 			else
1258 				status = nfs4_reset_session(clp);
1259 			if (status) {
1260 				if (status == -NFS4ERR_STALE_CLIENTID)
1261 					continue;
1262 				goto out_error;
1263 			}
1264 		}
1265 		/* First recover reboot state... */
1266 		if (test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
1267 			status = nfs4_do_reclaim(clp,
1268 				nfs4_reboot_recovery_ops[clp->cl_minorversion]);
1269 			if (status == -NFS4ERR_STALE_CLIENTID)
1270 				continue;
1271 			if (test_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state))
1272 				continue;
1273 			nfs4_state_end_reclaim_reboot(clp);
1274 			continue;
1275 		}
1276 
1277 		/* Now recover expired state... */
1278 		if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
1279 			status = nfs4_do_reclaim(clp,
1280 				nfs4_nograce_recovery_ops[clp->cl_minorversion]);
1281 			if (status < 0) {
1282 				set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
1283 				if (status == -NFS4ERR_STALE_CLIENTID)
1284 					continue;
1285 				if (status == -NFS4ERR_EXPIRED)
1286 					continue;
1287 				if (test_bit(NFS4CLNT_SESSION_SETUP,
1288 								&clp->cl_state))
1289 					continue;
1290 				goto out_error;
1291 			} else
1292 				nfs4_state_end_reclaim_nograce(clp);
1293 			continue;
1294 		}
1295 
1296 		if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
1297 			nfs_client_return_marked_delegations(clp);
1298 			continue;
1299 		}
1300 
1301 		nfs4_clear_state_manager_bit(clp);
1302 		/* Did we race with an attempt to give us more work? */
1303 		if (clp->cl_state == 0)
1304 			break;
1305 		if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
1306 			break;
1307 	}
1308 	return;
1309 out_error:
1310 	printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
1311 			" with error %d\n", clp->cl_hostname, -status);
1312 	if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
1313 		nfs4_state_end_reclaim_reboot(clp);
1314 	nfs4_clear_state_manager_bit(clp);
1315 }
1316 
1317 static int nfs4_run_state_manager(void *ptr)
1318 {
1319 	struct nfs_client *clp = ptr;
1320 
1321 	allow_signal(SIGKILL);
1322 	nfs4_state_manager(clp);
1323 	nfs_put_client(clp);
1324 	module_put_and_exit(0);
1325 	return 0;
1326 }
1327 
1328 /*
1329  * Local variables:
1330  *  c-basic-offset: 8
1331  * End:
1332  */
1333