xref: /openbmc/linux/fs/nfsd/nfs4state.c (revision 78c99ba1)
1 /*
2 *  linux/fs/nfsd/nfs4state.c
3 *
4 *  Copyright (c) 2001 The Regents of the University of Michigan.
5 *  All rights reserved.
6 *
7 *  Kendrick Smith <kmsmith@umich.edu>
8 *  Andy Adamson <kandros@umich.edu>
9 *
10 *  Redistribution and use in source and binary forms, with or without
11 *  modification, are permitted provided that the following conditions
12 *  are met:
13 *
14 *  1. Redistributions of source code must retain the above copyright
15 *     notice, this list of conditions and the following disclaimer.
16 *  2. Redistributions in binary form must reproduce the above copyright
17 *     notice, this list of conditions and the following disclaimer in the
18 *     documentation and/or other materials provided with the distribution.
19 *  3. Neither the name of the University nor the names of its
20 *     contributors may be used to endorse or promote products derived
21 *     from this software without specific prior written permission.
22 *
23 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26 *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30 *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 *
35 */
36 
37 #include <linux/param.h>
38 #include <linux/major.h>
39 #include <linux/slab.h>
40 
41 #include <linux/sunrpc/svc.h>
42 #include <linux/nfsd/nfsd.h>
43 #include <linux/nfsd/cache.h>
44 #include <linux/file.h>
45 #include <linux/mount.h>
46 #include <linux/workqueue.h>
47 #include <linux/smp_lock.h>
48 #include <linux/kthread.h>
49 #include <linux/nfs4.h>
50 #include <linux/nfsd/state.h>
51 #include <linux/nfsd/xdr4.h>
52 #include <linux/namei.h>
53 #include <linux/swap.h>
54 #include <linux/mutex.h>
55 #include <linux/lockd/bind.h>
56 #include <linux/module.h>
57 #include <linux/sunrpc/svcauth_gss.h>
58 
59 #define NFSDDBG_FACILITY                NFSDDBG_PROC
60 
61 /* Globals */
62 static time_t lease_time = 90;     /* default lease time */
63 static time_t user_lease_time = 90;
64 static time_t boot_time;
65 static u32 current_ownerid = 1;
66 static u32 current_fileid = 1;
67 static u32 current_delegid = 1;
68 static u32 nfs4_init;
69 static stateid_t zerostateid;             /* bits all 0 */
70 static stateid_t onestateid;              /* bits all 1 */
71 static u64 current_sessionid = 1;
72 
73 #define ZERO_STATEID(stateid) (!memcmp((stateid), &zerostateid, sizeof(stateid_t)))
74 #define ONE_STATEID(stateid)  (!memcmp((stateid), &onestateid, sizeof(stateid_t)))
75 
76 /* forward declarations */
77 static struct nfs4_stateid * find_stateid(stateid_t *stid, int flags);
78 static struct nfs4_delegation * find_delegation_stateid(struct inode *ino, stateid_t *stid);
79 static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
80 static void nfs4_set_recdir(char *recdir);
81 
82 /* Locking: */
83 
84 /* Currently used for almost all code touching nfsv4 state: */
85 static DEFINE_MUTEX(client_mutex);
86 
87 /*
88  * Currently used for the del_recall_lru and file hash table.  In an
89  * effort to decrease the scope of the client_mutex, this spinlock may
90  * eventually cover more:
91  */
92 static DEFINE_SPINLOCK(recall_lock);
93 
94 static struct kmem_cache *stateowner_slab = NULL;
95 static struct kmem_cache *file_slab = NULL;
96 static struct kmem_cache *stateid_slab = NULL;
97 static struct kmem_cache *deleg_slab = NULL;
98 
99 void
100 nfs4_lock_state(void)
101 {
102 	mutex_lock(&client_mutex);
103 }
104 
105 void
106 nfs4_unlock_state(void)
107 {
108 	mutex_unlock(&client_mutex);
109 }
110 
111 static inline u32
112 opaque_hashval(const void *ptr, int nbytes)
113 {
114 	unsigned char *cptr = (unsigned char *) ptr;
115 
116 	u32 x = 0;
117 	while (nbytes--) {
118 		x *= 37;
119 		x += *cptr++;
120 	}
121 	return x;
122 }
123 
124 static struct list_head del_recall_lru;
125 
126 static inline void
127 put_nfs4_file(struct nfs4_file *fi)
128 {
129 	if (atomic_dec_and_lock(&fi->fi_ref, &recall_lock)) {
130 		list_del(&fi->fi_hash);
131 		spin_unlock(&recall_lock);
132 		iput(fi->fi_inode);
133 		kmem_cache_free(file_slab, fi);
134 	}
135 }
136 
137 static inline void
138 get_nfs4_file(struct nfs4_file *fi)
139 {
140 	atomic_inc(&fi->fi_ref);
141 }
142 
143 static int num_delegations;
144 unsigned int max_delegations;
145 
146 /*
147  * Open owner state (share locks)
148  */
149 
150 /* hash tables for nfs4_stateowner */
151 #define OWNER_HASH_BITS              8
152 #define OWNER_HASH_SIZE             (1 << OWNER_HASH_BITS)
153 #define OWNER_HASH_MASK             (OWNER_HASH_SIZE - 1)
154 
155 #define ownerid_hashval(id) \
156         ((id) & OWNER_HASH_MASK)
157 #define ownerstr_hashval(clientid, ownername) \
158         (((clientid) + opaque_hashval((ownername.data), (ownername.len))) & OWNER_HASH_MASK)
159 
160 static struct list_head	ownerid_hashtbl[OWNER_HASH_SIZE];
161 static struct list_head	ownerstr_hashtbl[OWNER_HASH_SIZE];
162 
163 /* hash table for nfs4_file */
164 #define FILE_HASH_BITS                   8
165 #define FILE_HASH_SIZE                  (1 << FILE_HASH_BITS)
166 #define FILE_HASH_MASK                  (FILE_HASH_SIZE - 1)
167 /* hash table for (open)nfs4_stateid */
168 #define STATEID_HASH_BITS              10
169 #define STATEID_HASH_SIZE              (1 << STATEID_HASH_BITS)
170 #define STATEID_HASH_MASK              (STATEID_HASH_SIZE - 1)
171 
172 #define file_hashval(x) \
173         hash_ptr(x, FILE_HASH_BITS)
174 #define stateid_hashval(owner_id, file_id)  \
175         (((owner_id) + (file_id)) & STATEID_HASH_MASK)
176 
177 static struct list_head file_hashtbl[FILE_HASH_SIZE];
178 static struct list_head stateid_hashtbl[STATEID_HASH_SIZE];
179 
180 static struct nfs4_delegation *
181 alloc_init_deleg(struct nfs4_client *clp, struct nfs4_stateid *stp, struct svc_fh *current_fh, u32 type)
182 {
183 	struct nfs4_delegation *dp;
184 	struct nfs4_file *fp = stp->st_file;
185 	struct nfs4_callback *cb = &stp->st_stateowner->so_client->cl_callback;
186 
187 	dprintk("NFSD alloc_init_deleg\n");
188 	if (fp->fi_had_conflict)
189 		return NULL;
190 	if (num_delegations > max_delegations)
191 		return NULL;
192 	dp = kmem_cache_alloc(deleg_slab, GFP_KERNEL);
193 	if (dp == NULL)
194 		return dp;
195 	num_delegations++;
196 	INIT_LIST_HEAD(&dp->dl_perfile);
197 	INIT_LIST_HEAD(&dp->dl_perclnt);
198 	INIT_LIST_HEAD(&dp->dl_recall_lru);
199 	dp->dl_client = clp;
200 	get_nfs4_file(fp);
201 	dp->dl_file = fp;
202 	dp->dl_flock = NULL;
203 	get_file(stp->st_vfs_file);
204 	dp->dl_vfs_file = stp->st_vfs_file;
205 	dp->dl_type = type;
206 	dp->dl_recall.cbr_dp = NULL;
207 	dp->dl_recall.cbr_ident = cb->cb_ident;
208 	dp->dl_recall.cbr_trunc = 0;
209 	dp->dl_stateid.si_boot = boot_time;
210 	dp->dl_stateid.si_stateownerid = current_delegid++;
211 	dp->dl_stateid.si_fileid = 0;
212 	dp->dl_stateid.si_generation = 0;
213 	fh_copy_shallow(&dp->dl_fh, &current_fh->fh_handle);
214 	dp->dl_time = 0;
215 	atomic_set(&dp->dl_count, 1);
216 	list_add(&dp->dl_perfile, &fp->fi_delegations);
217 	list_add(&dp->dl_perclnt, &clp->cl_delegations);
218 	return dp;
219 }
220 
221 void
222 nfs4_put_delegation(struct nfs4_delegation *dp)
223 {
224 	if (atomic_dec_and_test(&dp->dl_count)) {
225 		dprintk("NFSD: freeing dp %p\n",dp);
226 		put_nfs4_file(dp->dl_file);
227 		kmem_cache_free(deleg_slab, dp);
228 		num_delegations--;
229 	}
230 }
231 
232 /* Remove the associated file_lock first, then remove the delegation.
233  * lease_modify() is called to remove the FS_LEASE file_lock from
234  * the i_flock list, eventually calling nfsd's lock_manager
235  * fl_release_callback.
236  */
237 static void
238 nfs4_close_delegation(struct nfs4_delegation *dp)
239 {
240 	struct file *filp = dp->dl_vfs_file;
241 
242 	dprintk("NFSD: close_delegation dp %p\n",dp);
243 	dp->dl_vfs_file = NULL;
244 	/* The following nfsd_close may not actually close the file,
245 	 * but we want to remove the lease in any case. */
246 	if (dp->dl_flock)
247 		vfs_setlease(filp, F_UNLCK, &dp->dl_flock);
248 	nfsd_close(filp);
249 }
250 
251 /* Called under the state lock. */
252 static void
253 unhash_delegation(struct nfs4_delegation *dp)
254 {
255 	list_del_init(&dp->dl_perfile);
256 	list_del_init(&dp->dl_perclnt);
257 	spin_lock(&recall_lock);
258 	list_del_init(&dp->dl_recall_lru);
259 	spin_unlock(&recall_lock);
260 	nfs4_close_delegation(dp);
261 	nfs4_put_delegation(dp);
262 }
263 
264 /*
265  * SETCLIENTID state
266  */
267 
268 /* Hash tables for nfs4_clientid state */
269 #define CLIENT_HASH_BITS                 4
270 #define CLIENT_HASH_SIZE                (1 << CLIENT_HASH_BITS)
271 #define CLIENT_HASH_MASK                (CLIENT_HASH_SIZE - 1)
272 
273 #define clientid_hashval(id) \
274 	((id) & CLIENT_HASH_MASK)
275 #define clientstr_hashval(name) \
276 	(opaque_hashval((name), 8) & CLIENT_HASH_MASK)
277 /*
278  * reclaim_str_hashtbl[] holds known client info from previous reset/reboot
279  * used in reboot/reset lease grace period processing
280  *
281  * conf_id_hashtbl[], and conf_str_hashtbl[] hold confirmed
282  * setclientid_confirmed info.
283  *
284  * unconf_str_hastbl[] and unconf_id_hashtbl[] hold unconfirmed
285  * setclientid info.
286  *
287  * client_lru holds client queue ordered by nfs4_client.cl_time
288  * for lease renewal.
289  *
290  * close_lru holds (open) stateowner queue ordered by nfs4_stateowner.so_time
291  * for last close replay.
292  */
293 static struct list_head	reclaim_str_hashtbl[CLIENT_HASH_SIZE];
294 static int reclaim_str_hashtbl_size = 0;
295 static struct list_head	conf_id_hashtbl[CLIENT_HASH_SIZE];
296 static struct list_head	conf_str_hashtbl[CLIENT_HASH_SIZE];
297 static struct list_head	unconf_str_hashtbl[CLIENT_HASH_SIZE];
298 static struct list_head	unconf_id_hashtbl[CLIENT_HASH_SIZE];
299 static struct list_head client_lru;
300 static struct list_head close_lru;
301 
302 static void unhash_generic_stateid(struct nfs4_stateid *stp)
303 {
304 	list_del(&stp->st_hash);
305 	list_del(&stp->st_perfile);
306 	list_del(&stp->st_perstateowner);
307 }
308 
309 static void free_generic_stateid(struct nfs4_stateid *stp)
310 {
311 	put_nfs4_file(stp->st_file);
312 	kmem_cache_free(stateid_slab, stp);
313 }
314 
315 static void release_lock_stateid(struct nfs4_stateid *stp)
316 {
317 	unhash_generic_stateid(stp);
318 	locks_remove_posix(stp->st_vfs_file, (fl_owner_t)stp->st_stateowner);
319 	free_generic_stateid(stp);
320 }
321 
322 static void unhash_lockowner(struct nfs4_stateowner *sop)
323 {
324 	struct nfs4_stateid *stp;
325 
326 	list_del(&sop->so_idhash);
327 	list_del(&sop->so_strhash);
328 	list_del(&sop->so_perstateid);
329 	while (!list_empty(&sop->so_stateids)) {
330 		stp = list_first_entry(&sop->so_stateids,
331 				struct nfs4_stateid, st_perstateowner);
332 		release_lock_stateid(stp);
333 	}
334 }
335 
336 static void release_lockowner(struct nfs4_stateowner *sop)
337 {
338 	unhash_lockowner(sop);
339 	nfs4_put_stateowner(sop);
340 }
341 
342 static void
343 release_stateid_lockowners(struct nfs4_stateid *open_stp)
344 {
345 	struct nfs4_stateowner *lock_sop;
346 
347 	while (!list_empty(&open_stp->st_lockowners)) {
348 		lock_sop = list_entry(open_stp->st_lockowners.next,
349 				struct nfs4_stateowner, so_perstateid);
350 		/* list_del(&open_stp->st_lockowners);  */
351 		BUG_ON(lock_sop->so_is_open_owner);
352 		release_lockowner(lock_sop);
353 	}
354 }
355 
356 static void release_open_stateid(struct nfs4_stateid *stp)
357 {
358 	unhash_generic_stateid(stp);
359 	release_stateid_lockowners(stp);
360 	nfsd_close(stp->st_vfs_file);
361 	free_generic_stateid(stp);
362 }
363 
364 static void unhash_openowner(struct nfs4_stateowner *sop)
365 {
366 	struct nfs4_stateid *stp;
367 
368 	list_del(&sop->so_idhash);
369 	list_del(&sop->so_strhash);
370 	list_del(&sop->so_perclient);
371 	list_del(&sop->so_perstateid); /* XXX: necessary? */
372 	while (!list_empty(&sop->so_stateids)) {
373 		stp = list_first_entry(&sop->so_stateids,
374 				struct nfs4_stateid, st_perstateowner);
375 		release_open_stateid(stp);
376 	}
377 }
378 
379 static void release_openowner(struct nfs4_stateowner *sop)
380 {
381 	unhash_openowner(sop);
382 	list_del(&sop->so_close_lru);
383 	nfs4_put_stateowner(sop);
384 }
385 
386 static DEFINE_SPINLOCK(sessionid_lock);
387 #define SESSION_HASH_SIZE	512
388 static struct list_head sessionid_hashtbl[SESSION_HASH_SIZE];
389 
390 static inline int
391 hash_sessionid(struct nfs4_sessionid *sessionid)
392 {
393 	struct nfsd4_sessionid *sid = (struct nfsd4_sessionid *)sessionid;
394 
395 	return sid->sequence % SESSION_HASH_SIZE;
396 }
397 
398 static inline void
399 dump_sessionid(const char *fn, struct nfs4_sessionid *sessionid)
400 {
401 	u32 *ptr = (u32 *)(&sessionid->data[0]);
402 	dprintk("%s: %u:%u:%u:%u\n", fn, ptr[0], ptr[1], ptr[2], ptr[3]);
403 }
404 
405 static void
406 gen_sessionid(struct nfsd4_session *ses)
407 {
408 	struct nfs4_client *clp = ses->se_client;
409 	struct nfsd4_sessionid *sid;
410 
411 	sid = (struct nfsd4_sessionid *)ses->se_sessionid.data;
412 	sid->clientid = clp->cl_clientid;
413 	sid->sequence = current_sessionid++;
414 	sid->reserved = 0;
415 }
416 
417 /*
418  * Give the client the number of slots it requests bound by
419  * NFSD_MAX_SLOTS_PER_SESSION and by sv_drc_max_pages.
420  *
421  * If we run out of pages (sv_drc_pages_used == sv_drc_max_pages) we
422  * should (up to a point) re-negotiate active sessions and reduce their
423  * slot usage to make rooom for new connections. For now we just fail the
424  * create session.
425  */
426 static int set_forechannel_maxreqs(struct nfsd4_channel_attrs *fchan)
427 {
428 	int status = 0, np = fchan->maxreqs * NFSD_PAGES_PER_SLOT;
429 
430 	spin_lock(&nfsd_serv->sv_lock);
431 	if (np + nfsd_serv->sv_drc_pages_used > nfsd_serv->sv_drc_max_pages)
432 		np = nfsd_serv->sv_drc_max_pages - nfsd_serv->sv_drc_pages_used;
433 	nfsd_serv->sv_drc_pages_used += np;
434 	spin_unlock(&nfsd_serv->sv_lock);
435 
436 	if (np <= 0) {
437 		status = nfserr_resource;
438 		fchan->maxreqs = 0;
439 	} else
440 		fchan->maxreqs = np / NFSD_PAGES_PER_SLOT;
441 
442 	return status;
443 }
444 
445 /*
446  * fchan holds the client values on input, and the server values on output
447  */
448 static int init_forechannel_attrs(struct svc_rqst *rqstp,
449 				    struct nfsd4_session *session,
450 				    struct nfsd4_channel_attrs *fchan)
451 {
452 	int status = 0;
453 	__u32   maxcount = svc_max_payload(rqstp);
454 
455 	/* headerpadsz set to zero in encode routine */
456 
457 	/* Use the client's max request and max response size if possible */
458 	if (fchan->maxreq_sz > maxcount)
459 		fchan->maxreq_sz = maxcount;
460 	session->se_fmaxreq_sz = fchan->maxreq_sz;
461 
462 	if (fchan->maxresp_sz > maxcount)
463 		fchan->maxresp_sz = maxcount;
464 	session->se_fmaxresp_sz = fchan->maxresp_sz;
465 
466 	/* Set the max response cached size our default which is
467 	 * a multiple of PAGE_SIZE and small */
468 	session->se_fmaxresp_cached = NFSD_PAGES_PER_SLOT * PAGE_SIZE;
469 	fchan->maxresp_cached = session->se_fmaxresp_cached;
470 
471 	/* Use the client's maxops if possible */
472 	if (fchan->maxops > NFSD_MAX_OPS_PER_COMPOUND)
473 		fchan->maxops = NFSD_MAX_OPS_PER_COMPOUND;
474 	session->se_fmaxops = fchan->maxops;
475 
476 	/* try to use the client requested number of slots */
477 	if (fchan->maxreqs > NFSD_MAX_SLOTS_PER_SESSION)
478 		fchan->maxreqs = NFSD_MAX_SLOTS_PER_SESSION;
479 
480 	/* FIXME: Error means no more DRC pages so the server should
481 	 * recover pages from existing sessions. For now fail session
482 	 * creation.
483 	 */
484 	status = set_forechannel_maxreqs(fchan);
485 
486 	session->se_fnumslots = fchan->maxreqs;
487 	return status;
488 }
489 
490 static int
491 alloc_init_session(struct svc_rqst *rqstp, struct nfs4_client *clp,
492 		   struct nfsd4_create_session *cses)
493 {
494 	struct nfsd4_session *new, tmp;
495 	int idx, status = nfserr_resource, slotsize;
496 
497 	memset(&tmp, 0, sizeof(tmp));
498 
499 	/* FIXME: For now, we just accept the client back channel attributes. */
500 	status = init_forechannel_attrs(rqstp, &tmp, &cses->fore_channel);
501 	if (status)
502 		goto out;
503 
504 	/* allocate struct nfsd4_session and slot table in one piece */
505 	slotsize = tmp.se_fnumslots * sizeof(struct nfsd4_slot);
506 	new = kzalloc(sizeof(*new) + slotsize, GFP_KERNEL);
507 	if (!new)
508 		goto out;
509 
510 	memcpy(new, &tmp, sizeof(*new));
511 
512 	new->se_client = clp;
513 	gen_sessionid(new);
514 	idx = hash_sessionid(&new->se_sessionid);
515 	memcpy(clp->cl_sessionid.data, new->se_sessionid.data,
516 	       NFS4_MAX_SESSIONID_LEN);
517 
518 	new->se_flags = cses->flags;
519 	kref_init(&new->se_ref);
520 	spin_lock(&sessionid_lock);
521 	list_add(&new->se_hash, &sessionid_hashtbl[idx]);
522 	list_add(&new->se_perclnt, &clp->cl_sessions);
523 	spin_unlock(&sessionid_lock);
524 
525 	status = nfs_ok;
526 out:
527 	return status;
528 }
529 
530 /* caller must hold sessionid_lock */
531 static struct nfsd4_session *
532 find_in_sessionid_hashtbl(struct nfs4_sessionid *sessionid)
533 {
534 	struct nfsd4_session *elem;
535 	int idx;
536 
537 	dump_sessionid(__func__, sessionid);
538 	idx = hash_sessionid(sessionid);
539 	dprintk("%s: idx is %d\n", __func__, idx);
540 	/* Search in the appropriate list */
541 	list_for_each_entry(elem, &sessionid_hashtbl[idx], se_hash) {
542 		dump_sessionid("list traversal", &elem->se_sessionid);
543 		if (!memcmp(elem->se_sessionid.data, sessionid->data,
544 			    NFS4_MAX_SESSIONID_LEN)) {
545 			return elem;
546 		}
547 	}
548 
549 	dprintk("%s: session not found\n", __func__);
550 	return NULL;
551 }
552 
553 /* caller must hold sessionid_lock */
554 static void
555 unhash_session(struct nfsd4_session *ses)
556 {
557 	list_del(&ses->se_hash);
558 	list_del(&ses->se_perclnt);
559 }
560 
561 static void
562 release_session(struct nfsd4_session *ses)
563 {
564 	spin_lock(&sessionid_lock);
565 	unhash_session(ses);
566 	spin_unlock(&sessionid_lock);
567 	nfsd4_put_session(ses);
568 }
569 
570 static void nfsd4_release_respages(struct page **respages, short resused);
571 
572 void
573 free_session(struct kref *kref)
574 {
575 	struct nfsd4_session *ses;
576 	int i;
577 
578 	ses = container_of(kref, struct nfsd4_session, se_ref);
579 	for (i = 0; i < ses->se_fnumslots; i++) {
580 		struct nfsd4_cache_entry *e = &ses->se_slots[i].sl_cache_entry;
581 		nfsd4_release_respages(e->ce_respages, e->ce_resused);
582 	}
583 	kfree(ses);
584 }
585 
586 static inline void
587 renew_client(struct nfs4_client *clp)
588 {
589 	/*
590 	* Move client to the end to the LRU list.
591 	*/
592 	dprintk("renewing client (clientid %08x/%08x)\n",
593 			clp->cl_clientid.cl_boot,
594 			clp->cl_clientid.cl_id);
595 	list_move_tail(&clp->cl_lru, &client_lru);
596 	clp->cl_time = get_seconds();
597 }
598 
599 /* SETCLIENTID and SETCLIENTID_CONFIRM Helper functions */
600 static int
601 STALE_CLIENTID(clientid_t *clid)
602 {
603 	if (clid->cl_boot == boot_time)
604 		return 0;
605 	dprintk("NFSD stale clientid (%08x/%08x) boot_time %08lx\n",
606 		clid->cl_boot, clid->cl_id, boot_time);
607 	return 1;
608 }
609 
610 /*
611  * XXX Should we use a slab cache ?
612  * This type of memory management is somewhat inefficient, but we use it
613  * anyway since SETCLIENTID is not a common operation.
614  */
615 static struct nfs4_client *alloc_client(struct xdr_netobj name)
616 {
617 	struct nfs4_client *clp;
618 
619 	clp = kzalloc(sizeof(struct nfs4_client), GFP_KERNEL);
620 	if (clp == NULL)
621 		return NULL;
622 	clp->cl_name.data = kmalloc(name.len, GFP_KERNEL);
623 	if (clp->cl_name.data == NULL) {
624 		kfree(clp);
625 		return NULL;
626 	}
627 	memcpy(clp->cl_name.data, name.data, name.len);
628 	clp->cl_name.len = name.len;
629 	return clp;
630 }
631 
632 static void
633 shutdown_callback_client(struct nfs4_client *clp)
634 {
635 	struct rpc_clnt *clnt = clp->cl_callback.cb_client;
636 
637 	if (clnt) {
638 		/*
639 		 * Callback threads take a reference on the client, so there
640 		 * should be no outstanding callbacks at this point.
641 		 */
642 		clp->cl_callback.cb_client = NULL;
643 		rpc_shutdown_client(clnt);
644 	}
645 }
646 
647 static inline void
648 free_client(struct nfs4_client *clp)
649 {
650 	shutdown_callback_client(clp);
651 	nfsd4_release_respages(clp->cl_slot.sl_cache_entry.ce_respages,
652 			     clp->cl_slot.sl_cache_entry.ce_resused);
653 	if (clp->cl_cred.cr_group_info)
654 		put_group_info(clp->cl_cred.cr_group_info);
655 	kfree(clp->cl_principal);
656 	kfree(clp->cl_name.data);
657 	kfree(clp);
658 }
659 
660 void
661 put_nfs4_client(struct nfs4_client *clp)
662 {
663 	if (atomic_dec_and_test(&clp->cl_count))
664 		free_client(clp);
665 }
666 
667 static void
668 expire_client(struct nfs4_client *clp)
669 {
670 	struct nfs4_stateowner *sop;
671 	struct nfs4_delegation *dp;
672 	struct list_head reaplist;
673 
674 	dprintk("NFSD: expire_client cl_count %d\n",
675 	                    atomic_read(&clp->cl_count));
676 
677 	INIT_LIST_HEAD(&reaplist);
678 	spin_lock(&recall_lock);
679 	while (!list_empty(&clp->cl_delegations)) {
680 		dp = list_entry(clp->cl_delegations.next, struct nfs4_delegation, dl_perclnt);
681 		dprintk("NFSD: expire client. dp %p, fp %p\n", dp,
682 				dp->dl_flock);
683 		list_del_init(&dp->dl_perclnt);
684 		list_move(&dp->dl_recall_lru, &reaplist);
685 	}
686 	spin_unlock(&recall_lock);
687 	while (!list_empty(&reaplist)) {
688 		dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru);
689 		list_del_init(&dp->dl_recall_lru);
690 		unhash_delegation(dp);
691 	}
692 	list_del(&clp->cl_idhash);
693 	list_del(&clp->cl_strhash);
694 	list_del(&clp->cl_lru);
695 	while (!list_empty(&clp->cl_openowners)) {
696 		sop = list_entry(clp->cl_openowners.next, struct nfs4_stateowner, so_perclient);
697 		release_openowner(sop);
698 	}
699 	while (!list_empty(&clp->cl_sessions)) {
700 		struct nfsd4_session  *ses;
701 		ses = list_entry(clp->cl_sessions.next, struct nfsd4_session,
702 				 se_perclnt);
703 		release_session(ses);
704 	}
705 	put_nfs4_client(clp);
706 }
707 
708 static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir)
709 {
710 	struct nfs4_client *clp;
711 
712 	clp = alloc_client(name);
713 	if (clp == NULL)
714 		return NULL;
715 	memcpy(clp->cl_recdir, recdir, HEXDIR_LEN);
716 	atomic_set(&clp->cl_count, 1);
717 	atomic_set(&clp->cl_callback.cb_set, 0);
718 	INIT_LIST_HEAD(&clp->cl_idhash);
719 	INIT_LIST_HEAD(&clp->cl_strhash);
720 	INIT_LIST_HEAD(&clp->cl_openowners);
721 	INIT_LIST_HEAD(&clp->cl_delegations);
722 	INIT_LIST_HEAD(&clp->cl_sessions);
723 	INIT_LIST_HEAD(&clp->cl_lru);
724 	return clp;
725 }
726 
727 static void copy_verf(struct nfs4_client *target, nfs4_verifier *source)
728 {
729 	memcpy(target->cl_verifier.data, source->data,
730 			sizeof(target->cl_verifier.data));
731 }
732 
733 static void copy_clid(struct nfs4_client *target, struct nfs4_client *source)
734 {
735 	target->cl_clientid.cl_boot = source->cl_clientid.cl_boot;
736 	target->cl_clientid.cl_id = source->cl_clientid.cl_id;
737 }
738 
739 static void copy_cred(struct svc_cred *target, struct svc_cred *source)
740 {
741 	target->cr_uid = source->cr_uid;
742 	target->cr_gid = source->cr_gid;
743 	target->cr_group_info = source->cr_group_info;
744 	get_group_info(target->cr_group_info);
745 }
746 
747 static int same_name(const char *n1, const char *n2)
748 {
749 	return 0 == memcmp(n1, n2, HEXDIR_LEN);
750 }
751 
752 static int
753 same_verf(nfs4_verifier *v1, nfs4_verifier *v2)
754 {
755 	return 0 == memcmp(v1->data, v2->data, sizeof(v1->data));
756 }
757 
758 static int
759 same_clid(clientid_t *cl1, clientid_t *cl2)
760 {
761 	return (cl1->cl_boot == cl2->cl_boot) && (cl1->cl_id == cl2->cl_id);
762 }
763 
764 /* XXX what about NGROUP */
765 static int
766 same_creds(struct svc_cred *cr1, struct svc_cred *cr2)
767 {
768 	return cr1->cr_uid == cr2->cr_uid;
769 }
770 
771 static void gen_clid(struct nfs4_client *clp)
772 {
773 	static u32 current_clientid = 1;
774 
775 	clp->cl_clientid.cl_boot = boot_time;
776 	clp->cl_clientid.cl_id = current_clientid++;
777 }
778 
779 static void gen_confirm(struct nfs4_client *clp)
780 {
781 	static u32 i;
782 	u32 *p;
783 
784 	p = (u32 *)clp->cl_confirm.data;
785 	*p++ = get_seconds();
786 	*p++ = i++;
787 }
788 
789 static int check_name(struct xdr_netobj name)
790 {
791 	if (name.len == 0)
792 		return 0;
793 	if (name.len > NFS4_OPAQUE_LIMIT) {
794 		dprintk("NFSD: check_name: name too long(%d)!\n", name.len);
795 		return 0;
796 	}
797 	return 1;
798 }
799 
800 static void
801 add_to_unconfirmed(struct nfs4_client *clp, unsigned int strhashval)
802 {
803 	unsigned int idhashval;
804 
805 	list_add(&clp->cl_strhash, &unconf_str_hashtbl[strhashval]);
806 	idhashval = clientid_hashval(clp->cl_clientid.cl_id);
807 	list_add(&clp->cl_idhash, &unconf_id_hashtbl[idhashval]);
808 	list_add_tail(&clp->cl_lru, &client_lru);
809 	clp->cl_time = get_seconds();
810 }
811 
812 static void
813 move_to_confirmed(struct nfs4_client *clp)
814 {
815 	unsigned int idhashval = clientid_hashval(clp->cl_clientid.cl_id);
816 	unsigned int strhashval;
817 
818 	dprintk("NFSD: move_to_confirm nfs4_client %p\n", clp);
819 	list_del_init(&clp->cl_strhash);
820 	list_move(&clp->cl_idhash, &conf_id_hashtbl[idhashval]);
821 	strhashval = clientstr_hashval(clp->cl_recdir);
822 	list_add(&clp->cl_strhash, &conf_str_hashtbl[strhashval]);
823 	renew_client(clp);
824 }
825 
826 static struct nfs4_client *
827 find_confirmed_client(clientid_t *clid)
828 {
829 	struct nfs4_client *clp;
830 	unsigned int idhashval = clientid_hashval(clid->cl_id);
831 
832 	list_for_each_entry(clp, &conf_id_hashtbl[idhashval], cl_idhash) {
833 		if (same_clid(&clp->cl_clientid, clid))
834 			return clp;
835 	}
836 	return NULL;
837 }
838 
839 static struct nfs4_client *
840 find_unconfirmed_client(clientid_t *clid)
841 {
842 	struct nfs4_client *clp;
843 	unsigned int idhashval = clientid_hashval(clid->cl_id);
844 
845 	list_for_each_entry(clp, &unconf_id_hashtbl[idhashval], cl_idhash) {
846 		if (same_clid(&clp->cl_clientid, clid))
847 			return clp;
848 	}
849 	return NULL;
850 }
851 
852 /*
853  * Return 1 iff clp's clientid establishment method matches the use_exchange_id
854  * parameter. Matching is based on the fact the at least one of the
855  * EXCHGID4_FLAG_USE_{NON_PNFS,PNFS_MDS,PNFS_DS} flags must be set for v4.1
856  *
857  * FIXME: we need to unify the clientid namespaces for nfsv4.x
858  * and correctly deal with client upgrade/downgrade in EXCHANGE_ID
859  * and SET_CLIENTID{,_CONFIRM}
860  */
861 static inline int
862 match_clientid_establishment(struct nfs4_client *clp, bool use_exchange_id)
863 {
864 	bool has_exchange_flags = (clp->cl_exchange_flags != 0);
865 	return use_exchange_id == has_exchange_flags;
866 }
867 
868 static struct nfs4_client *
869 find_confirmed_client_by_str(const char *dname, unsigned int hashval,
870 			     bool use_exchange_id)
871 {
872 	struct nfs4_client *clp;
873 
874 	list_for_each_entry(clp, &conf_str_hashtbl[hashval], cl_strhash) {
875 		if (same_name(clp->cl_recdir, dname) &&
876 		    match_clientid_establishment(clp, use_exchange_id))
877 			return clp;
878 	}
879 	return NULL;
880 }
881 
882 static struct nfs4_client *
883 find_unconfirmed_client_by_str(const char *dname, unsigned int hashval,
884 			       bool use_exchange_id)
885 {
886 	struct nfs4_client *clp;
887 
888 	list_for_each_entry(clp, &unconf_str_hashtbl[hashval], cl_strhash) {
889 		if (same_name(clp->cl_recdir, dname) &&
890 		    match_clientid_establishment(clp, use_exchange_id))
891 			return clp;
892 	}
893 	return NULL;
894 }
895 
896 /* a helper function for parse_callback */
897 static int
898 parse_octet(unsigned int *lenp, char **addrp)
899 {
900 	unsigned int len = *lenp;
901 	char *p = *addrp;
902 	int n = -1;
903 	char c;
904 
905 	for (;;) {
906 		if (!len)
907 			break;
908 		len--;
909 		c = *p++;
910 		if (c == '.')
911 			break;
912 		if ((c < '0') || (c > '9')) {
913 			n = -1;
914 			break;
915 		}
916 		if (n < 0)
917 			n = 0;
918 		n = (n * 10) + (c - '0');
919 		if (n > 255) {
920 			n = -1;
921 			break;
922 		}
923 	}
924 	*lenp = len;
925 	*addrp = p;
926 	return n;
927 }
928 
929 /* parse and set the setclientid ipv4 callback address */
930 static int
931 parse_ipv4(unsigned int addr_len, char *addr_val, unsigned int *cbaddrp, unsigned short *cbportp)
932 {
933 	int temp = 0;
934 	u32 cbaddr = 0;
935 	u16 cbport = 0;
936 	u32 addrlen = addr_len;
937 	char *addr = addr_val;
938 	int i, shift;
939 
940 	/* ipaddress */
941 	shift = 24;
942 	for(i = 4; i > 0  ; i--) {
943 		if ((temp = parse_octet(&addrlen, &addr)) < 0) {
944 			return 0;
945 		}
946 		cbaddr |= (temp << shift);
947 		if (shift > 0)
948 		shift -= 8;
949 	}
950 	*cbaddrp = cbaddr;
951 
952 	/* port */
953 	shift = 8;
954 	for(i = 2; i > 0  ; i--) {
955 		if ((temp = parse_octet(&addrlen, &addr)) < 0) {
956 			return 0;
957 		}
958 		cbport |= (temp << shift);
959 		if (shift > 0)
960 			shift -= 8;
961 	}
962 	*cbportp = cbport;
963 	return 1;
964 }
965 
966 static void
967 gen_callback(struct nfs4_client *clp, struct nfsd4_setclientid *se)
968 {
969 	struct nfs4_callback *cb = &clp->cl_callback;
970 
971 	/* Currently, we only support tcp for the callback channel */
972 	if ((se->se_callback_netid_len != 3) || memcmp((char *)se->se_callback_netid_val, "tcp", 3))
973 		goto out_err;
974 
975 	if ( !(parse_ipv4(se->se_callback_addr_len, se->se_callback_addr_val,
976 	                 &cb->cb_addr, &cb->cb_port)))
977 		goto out_err;
978 	cb->cb_prog = se->se_callback_prog;
979 	cb->cb_ident = se->se_callback_ident;
980 	return;
981 out_err:
982 	dprintk(KERN_INFO "NFSD: this client (clientid %08x/%08x) "
983 		"will not receive delegations\n",
984 		clp->cl_clientid.cl_boot, clp->cl_clientid.cl_id);
985 
986 	return;
987 }
988 
989 void
990 nfsd4_set_statp(struct svc_rqst *rqstp, __be32 *statp)
991 {
992 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
993 
994 	resp->cstate.statp = statp;
995 }
996 
997 /*
998  * Dereference the result pages.
999  */
1000 static void
1001 nfsd4_release_respages(struct page **respages, short resused)
1002 {
1003 	int i;
1004 
1005 	dprintk("--> %s\n", __func__);
1006 	for (i = 0; i < resused; i++) {
1007 		if (!respages[i])
1008 			continue;
1009 		put_page(respages[i]);
1010 		respages[i] = NULL;
1011 	}
1012 }
1013 
1014 static void
1015 nfsd4_copy_pages(struct page **topages, struct page **frompages, short count)
1016 {
1017 	int i;
1018 
1019 	for (i = 0; i < count; i++) {
1020 		topages[i] = frompages[i];
1021 		if (!topages[i])
1022 			continue;
1023 		get_page(topages[i]);
1024 	}
1025 }
1026 
1027 /*
1028  * Cache the reply pages up to NFSD_PAGES_PER_SLOT + 1, clearing the previous
1029  * pages. We add a page to NFSD_PAGES_PER_SLOT for the case where the total
1030  * length of the XDR response is less than se_fmaxresp_cached
1031  * (NFSD_PAGES_PER_SLOT * PAGE_SIZE) but the xdr_buf pages is used for a
1032  * of the reply (e.g. readdir).
1033  *
1034  * Store the base and length of the rq_req.head[0] page
1035  * of the NFSv4.1 data, just past the rpc header.
1036  */
1037 void
1038 nfsd4_store_cache_entry(struct nfsd4_compoundres *resp)
1039 {
1040 	struct nfsd4_cache_entry *entry = &resp->cstate.slot->sl_cache_entry;
1041 	struct svc_rqst *rqstp = resp->rqstp;
1042 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
1043 	struct nfsd4_op *op = &args->ops[resp->opcnt];
1044 	struct kvec *resv = &rqstp->rq_res.head[0];
1045 
1046 	dprintk("--> %s entry %p\n", __func__, entry);
1047 
1048 	/* Don't cache a failed OP_SEQUENCE. */
1049 	if (resp->opcnt == 1 && op->opnum == OP_SEQUENCE && resp->cstate.status)
1050 		return;
1051 
1052 	nfsd4_release_respages(entry->ce_respages, entry->ce_resused);
1053 	entry->ce_opcnt = resp->opcnt;
1054 	entry->ce_status = resp->cstate.status;
1055 
1056 	/*
1057 	 * Don't need a page to cache just the sequence operation - the slot
1058 	 * does this for us!
1059 	 */
1060 
1061 	if (nfsd4_not_cached(resp)) {
1062 		entry->ce_resused = 0;
1063 		entry->ce_rpchdrlen = 0;
1064 		dprintk("%s Just cache SEQUENCE. ce_cachethis %d\n", __func__,
1065 			resp->cstate.slot->sl_cache_entry.ce_cachethis);
1066 		return;
1067 	}
1068 	entry->ce_resused = rqstp->rq_resused;
1069 	if (entry->ce_resused > NFSD_PAGES_PER_SLOT + 1)
1070 		entry->ce_resused = NFSD_PAGES_PER_SLOT + 1;
1071 	nfsd4_copy_pages(entry->ce_respages, rqstp->rq_respages,
1072 			 entry->ce_resused);
1073 	entry->ce_datav.iov_base = resp->cstate.statp;
1074 	entry->ce_datav.iov_len = resv->iov_len - ((char *)resp->cstate.statp -
1075 				(char *)page_address(rqstp->rq_respages[0]));
1076 	/* Current request rpc header length*/
1077 	entry->ce_rpchdrlen = (char *)resp->cstate.statp -
1078 				(char *)page_address(rqstp->rq_respages[0]);
1079 }
1080 
1081 /*
1082  * We keep the rpc header, but take the nfs reply from the replycache.
1083  */
1084 static int
1085 nfsd41_copy_replay_data(struct nfsd4_compoundres *resp,
1086 			struct nfsd4_cache_entry *entry)
1087 {
1088 	struct svc_rqst *rqstp = resp->rqstp;
1089 	struct kvec *resv = &resp->rqstp->rq_res.head[0];
1090 	int len;
1091 
1092 	/* Current request rpc header length*/
1093 	len = (char *)resp->cstate.statp -
1094 			(char *)page_address(rqstp->rq_respages[0]);
1095 	if (entry->ce_datav.iov_len + len > PAGE_SIZE) {
1096 		dprintk("%s v41 cached reply too large (%Zd).\n", __func__,
1097 			entry->ce_datav.iov_len);
1098 		return 0;
1099 	}
1100 	/* copy the cached reply nfsd data past the current rpc header */
1101 	memcpy((char *)resv->iov_base + len, entry->ce_datav.iov_base,
1102 		entry->ce_datav.iov_len);
1103 	resv->iov_len = len + entry->ce_datav.iov_len;
1104 	return 1;
1105 }
1106 
1107 /*
1108  * Keep the first page of the replay. Copy the NFSv4.1 data from the first
1109  * cached page.  Replace any futher replay pages from the cache.
1110  */
1111 __be32
1112 nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp,
1113 			 struct nfsd4_sequence *seq)
1114 {
1115 	struct nfsd4_cache_entry *entry = &resp->cstate.slot->sl_cache_entry;
1116 	__be32 status;
1117 
1118 	dprintk("--> %s entry %p\n", __func__, entry);
1119 
1120 	/*
1121 	 * If this is just the sequence operation, we did not keep
1122 	 * a page in the cache entry because we can just use the
1123 	 * slot info stored in struct nfsd4_sequence that was checked
1124 	 * against the slot in nfsd4_sequence().
1125 	 *
1126 	 * This occurs when seq->cachethis is FALSE, or when the client
1127 	 * session inactivity timer fires and a solo sequence operation
1128 	 * is sent (lease renewal).
1129 	 */
1130 	if (seq && nfsd4_not_cached(resp)) {
1131 		seq->maxslots = resp->cstate.session->se_fnumslots;
1132 		return nfs_ok;
1133 	}
1134 
1135 	if (!nfsd41_copy_replay_data(resp, entry)) {
1136 		/*
1137 		 * Not enough room to use the replay rpc header, send the
1138 		 * cached header. Release all the allocated result pages.
1139 		 */
1140 		svc_free_res_pages(resp->rqstp);
1141 		nfsd4_copy_pages(resp->rqstp->rq_respages, entry->ce_respages,
1142 			entry->ce_resused);
1143 	} else {
1144 		/* Release all but the first allocated result page */
1145 
1146 		resp->rqstp->rq_resused--;
1147 		svc_free_res_pages(resp->rqstp);
1148 
1149 		nfsd4_copy_pages(&resp->rqstp->rq_respages[1],
1150 				 &entry->ce_respages[1],
1151 				 entry->ce_resused - 1);
1152 	}
1153 
1154 	resp->rqstp->rq_resused = entry->ce_resused;
1155 	resp->opcnt = entry->ce_opcnt;
1156 	resp->cstate.iovlen = entry->ce_datav.iov_len + entry->ce_rpchdrlen;
1157 	status = entry->ce_status;
1158 
1159 	return status;
1160 }
1161 
1162 /*
1163  * Set the exchange_id flags returned by the server.
1164  */
1165 static void
1166 nfsd4_set_ex_flags(struct nfs4_client *new, struct nfsd4_exchange_id *clid)
1167 {
1168 	/* pNFS is not supported */
1169 	new->cl_exchange_flags |= EXCHGID4_FLAG_USE_NON_PNFS;
1170 
1171 	/* Referrals are supported, Migration is not. */
1172 	new->cl_exchange_flags |= EXCHGID4_FLAG_SUPP_MOVED_REFER;
1173 
1174 	/* set the wire flags to return to client. */
1175 	clid->flags = new->cl_exchange_flags;
1176 }
1177 
1178 __be32
1179 nfsd4_exchange_id(struct svc_rqst *rqstp,
1180 		  struct nfsd4_compound_state *cstate,
1181 		  struct nfsd4_exchange_id *exid)
1182 {
1183 	struct nfs4_client *unconf, *conf, *new;
1184 	int status;
1185 	unsigned int		strhashval;
1186 	char			dname[HEXDIR_LEN];
1187 	nfs4_verifier		verf = exid->verifier;
1188 	u32			ip_addr = svc_addr_in(rqstp)->sin_addr.s_addr;
1189 
1190 	dprintk("%s rqstp=%p exid=%p clname.len=%u clname.data=%p "
1191 		" ip_addr=%u flags %x, spa_how %d\n",
1192 		__func__, rqstp, exid, exid->clname.len, exid->clname.data,
1193 		ip_addr, exid->flags, exid->spa_how);
1194 
1195 	if (!check_name(exid->clname) || (exid->flags & ~EXCHGID4_FLAG_MASK_A))
1196 		return nfserr_inval;
1197 
1198 	/* Currently only support SP4_NONE */
1199 	switch (exid->spa_how) {
1200 	case SP4_NONE:
1201 		break;
1202 	case SP4_SSV:
1203 		return nfserr_encr_alg_unsupp;
1204 	default:
1205 		BUG();				/* checked by xdr code */
1206 	case SP4_MACH_CRED:
1207 		return nfserr_serverfault;	/* no excuse :-/ */
1208 	}
1209 
1210 	status = nfs4_make_rec_clidname(dname, &exid->clname);
1211 
1212 	if (status)
1213 		goto error;
1214 
1215 	strhashval = clientstr_hashval(dname);
1216 
1217 	nfs4_lock_state();
1218 	status = nfs_ok;
1219 
1220 	conf = find_confirmed_client_by_str(dname, strhashval, true);
1221 	if (conf) {
1222 		if (!same_verf(&verf, &conf->cl_verifier)) {
1223 			/* 18.35.4 case 8 */
1224 			if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) {
1225 				status = nfserr_not_same;
1226 				goto out;
1227 			}
1228 			/* Client reboot: destroy old state */
1229 			expire_client(conf);
1230 			goto out_new;
1231 		}
1232 		if (!same_creds(&conf->cl_cred, &rqstp->rq_cred)) {
1233 			/* 18.35.4 case 9 */
1234 			if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) {
1235 				status = nfserr_perm;
1236 				goto out;
1237 			}
1238 			expire_client(conf);
1239 			goto out_new;
1240 		}
1241 		if (ip_addr != conf->cl_addr &&
1242 		    !(exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A)) {
1243 			/* Client collision. 18.35.4 case 3 */
1244 			status = nfserr_clid_inuse;
1245 			goto out;
1246 		}
1247 		/*
1248 		 * Set bit when the owner id and verifier map to an already
1249 		 * confirmed client id (18.35.3).
1250 		 */
1251 		exid->flags |= EXCHGID4_FLAG_CONFIRMED_R;
1252 
1253 		/*
1254 		 * Falling into 18.35.4 case 2, possible router replay.
1255 		 * Leave confirmed record intact and return same result.
1256 		 */
1257 		copy_verf(conf, &verf);
1258 		new = conf;
1259 		goto out_copy;
1260 	} else {
1261 		/* 18.35.4 case 7 */
1262 		if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) {
1263 			status = nfserr_noent;
1264 			goto out;
1265 		}
1266 	}
1267 
1268 	unconf  = find_unconfirmed_client_by_str(dname, strhashval, true);
1269 	if (unconf) {
1270 		/*
1271 		 * Possible retry or client restart.  Per 18.35.4 case 4,
1272 		 * a new unconfirmed record should be generated regardless
1273 		 * of whether any properties have changed.
1274 		 */
1275 		expire_client(unconf);
1276 	}
1277 
1278 out_new:
1279 	/* Normal case */
1280 	new = create_client(exid->clname, dname);
1281 	if (new == NULL) {
1282 		status = nfserr_resource;
1283 		goto out;
1284 	}
1285 
1286 	copy_verf(new, &verf);
1287 	copy_cred(&new->cl_cred, &rqstp->rq_cred);
1288 	new->cl_addr = ip_addr;
1289 	gen_clid(new);
1290 	gen_confirm(new);
1291 	add_to_unconfirmed(new, strhashval);
1292 out_copy:
1293 	exid->clientid.cl_boot = new->cl_clientid.cl_boot;
1294 	exid->clientid.cl_id = new->cl_clientid.cl_id;
1295 
1296 	new->cl_slot.sl_seqid = 0;
1297 	exid->seqid = 1;
1298 	nfsd4_set_ex_flags(new, exid);
1299 
1300 	dprintk("nfsd4_exchange_id seqid %d flags %x\n",
1301 		new->cl_slot.sl_seqid, new->cl_exchange_flags);
1302 	status = nfs_ok;
1303 
1304 out:
1305 	nfs4_unlock_state();
1306 error:
1307 	dprintk("nfsd4_exchange_id returns %d\n", ntohl(status));
1308 	return status;
1309 }
1310 
1311 static int
1312 check_slot_seqid(u32 seqid, struct nfsd4_slot *slot)
1313 {
1314 	dprintk("%s enter. seqid %d slot->sl_seqid %d\n", __func__, seqid,
1315 		slot->sl_seqid);
1316 
1317 	/* The slot is in use, and no response has been sent. */
1318 	if (slot->sl_inuse) {
1319 		if (seqid == slot->sl_seqid)
1320 			return nfserr_jukebox;
1321 		else
1322 			return nfserr_seq_misordered;
1323 	}
1324 	/* Normal */
1325 	if (likely(seqid == slot->sl_seqid + 1))
1326 		return nfs_ok;
1327 	/* Replay */
1328 	if (seqid == slot->sl_seqid)
1329 		return nfserr_replay_cache;
1330 	/* Wraparound */
1331 	if (seqid == 1 && (slot->sl_seqid + 1) == 0)
1332 		return nfs_ok;
1333 	/* Misordered replay or misordered new request */
1334 	return nfserr_seq_misordered;
1335 }
1336 
1337 __be32
1338 nfsd4_create_session(struct svc_rqst *rqstp,
1339 		     struct nfsd4_compound_state *cstate,
1340 		     struct nfsd4_create_session *cr_ses)
1341 {
1342 	u32 ip_addr = svc_addr_in(rqstp)->sin_addr.s_addr;
1343 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
1344 	struct nfs4_client *conf, *unconf;
1345 	struct nfsd4_slot *slot = NULL;
1346 	int status = 0;
1347 
1348 	nfs4_lock_state();
1349 	unconf = find_unconfirmed_client(&cr_ses->clientid);
1350 	conf = find_confirmed_client(&cr_ses->clientid);
1351 
1352 	if (conf) {
1353 		slot = &conf->cl_slot;
1354 		status = check_slot_seqid(cr_ses->seqid, slot);
1355 		if (status == nfserr_replay_cache) {
1356 			dprintk("Got a create_session replay! seqid= %d\n",
1357 				slot->sl_seqid);
1358 			cstate->slot = slot;
1359 			cstate->status = status;
1360 			/* Return the cached reply status */
1361 			status = nfsd4_replay_cache_entry(resp, NULL);
1362 			goto out;
1363 		} else if (cr_ses->seqid != conf->cl_slot.sl_seqid + 1) {
1364 			status = nfserr_seq_misordered;
1365 			dprintk("Sequence misordered!\n");
1366 			dprintk("Expected seqid= %d but got seqid= %d\n",
1367 				slot->sl_seqid, cr_ses->seqid);
1368 			goto out;
1369 		}
1370 		conf->cl_slot.sl_seqid++;
1371 	} else if (unconf) {
1372 		if (!same_creds(&unconf->cl_cred, &rqstp->rq_cred) ||
1373 		    (ip_addr != unconf->cl_addr)) {
1374 			status = nfserr_clid_inuse;
1375 			goto out;
1376 		}
1377 
1378 		slot = &unconf->cl_slot;
1379 		status = check_slot_seqid(cr_ses->seqid, slot);
1380 		if (status) {
1381 			/* an unconfirmed replay returns misordered */
1382 			status = nfserr_seq_misordered;
1383 			goto out;
1384 		}
1385 
1386 		slot->sl_seqid++; /* from 0 to 1 */
1387 		move_to_confirmed(unconf);
1388 
1389 		/*
1390 		 * We do not support RDMA or persistent sessions
1391 		 */
1392 		cr_ses->flags &= ~SESSION4_PERSIST;
1393 		cr_ses->flags &= ~SESSION4_RDMA;
1394 
1395 		conf = unconf;
1396 	} else {
1397 		status = nfserr_stale_clientid;
1398 		goto out;
1399 	}
1400 
1401 	status = alloc_init_session(rqstp, conf, cr_ses);
1402 	if (status)
1403 		goto out;
1404 
1405 	memcpy(cr_ses->sessionid.data, conf->cl_sessionid.data,
1406 	       NFS4_MAX_SESSIONID_LEN);
1407 	cr_ses->seqid = slot->sl_seqid;
1408 
1409 	slot->sl_inuse = true;
1410 	cstate->slot = slot;
1411 	/* Ensure a page is used for the cache */
1412 	slot->sl_cache_entry.ce_cachethis = 1;
1413 out:
1414 	nfs4_unlock_state();
1415 	dprintk("%s returns %d\n", __func__, ntohl(status));
1416 	return status;
1417 }
1418 
1419 __be32
1420 nfsd4_destroy_session(struct svc_rqst *r,
1421 		      struct nfsd4_compound_state *cstate,
1422 		      struct nfsd4_destroy_session *sessionid)
1423 {
1424 	struct nfsd4_session *ses;
1425 	u32 status = nfserr_badsession;
1426 
1427 	/* Notes:
1428 	 * - The confirmed nfs4_client->cl_sessionid holds destroyed sessinid
1429 	 * - Should we return nfserr_back_chan_busy if waiting for
1430 	 *   callbacks on to-be-destroyed session?
1431 	 * - Do we need to clear any callback info from previous session?
1432 	 */
1433 
1434 	dump_sessionid(__func__, &sessionid->sessionid);
1435 	spin_lock(&sessionid_lock);
1436 	ses = find_in_sessionid_hashtbl(&sessionid->sessionid);
1437 	if (!ses) {
1438 		spin_unlock(&sessionid_lock);
1439 		goto out;
1440 	}
1441 
1442 	unhash_session(ses);
1443 	spin_unlock(&sessionid_lock);
1444 
1445 	/* wait for callbacks */
1446 	shutdown_callback_client(ses->se_client);
1447 	nfsd4_put_session(ses);
1448 	status = nfs_ok;
1449 out:
1450 	dprintk("%s returns %d\n", __func__, ntohl(status));
1451 	return status;
1452 }
1453 
1454 __be32
1455 nfsd4_sequence(struct svc_rqst *rqstp,
1456 	       struct nfsd4_compound_state *cstate,
1457 	       struct nfsd4_sequence *seq)
1458 {
1459 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
1460 	struct nfsd4_session *session;
1461 	struct nfsd4_slot *slot;
1462 	int status;
1463 
1464 	if (resp->opcnt != 1)
1465 		return nfserr_sequence_pos;
1466 
1467 	spin_lock(&sessionid_lock);
1468 	status = nfserr_badsession;
1469 	session = find_in_sessionid_hashtbl(&seq->sessionid);
1470 	if (!session)
1471 		goto out;
1472 
1473 	status = nfserr_badslot;
1474 	if (seq->slotid >= session->se_fnumslots)
1475 		goto out;
1476 
1477 	slot = &session->se_slots[seq->slotid];
1478 	dprintk("%s: slotid %d\n", __func__, seq->slotid);
1479 
1480 	status = check_slot_seqid(seq->seqid, slot);
1481 	if (status == nfserr_replay_cache) {
1482 		cstate->slot = slot;
1483 		cstate->session = session;
1484 		/* Return the cached reply status and set cstate->status
1485 		 * for nfsd4_svc_encode_compoundres processing */
1486 		status = nfsd4_replay_cache_entry(resp, seq);
1487 		cstate->status = nfserr_replay_cache;
1488 		goto replay_cache;
1489 	}
1490 	if (status)
1491 		goto out;
1492 
1493 	/* Success! bump slot seqid */
1494 	slot->sl_inuse = true;
1495 	slot->sl_seqid = seq->seqid;
1496 	slot->sl_cache_entry.ce_cachethis = seq->cachethis;
1497 	/* Always set the cache entry cachethis for solo sequence */
1498 	if (nfsd4_is_solo_sequence(resp))
1499 		slot->sl_cache_entry.ce_cachethis = 1;
1500 
1501 	cstate->slot = slot;
1502 	cstate->session = session;
1503 
1504 replay_cache:
1505 	/* Renew the clientid on success and on replay.
1506 	 * Hold a session reference until done processing the compound:
1507 	 * nfsd4_put_session called only if the cstate slot is set.
1508 	 */
1509 	renew_client(session->se_client);
1510 	nfsd4_get_session(session);
1511 out:
1512 	spin_unlock(&sessionid_lock);
1513 	dprintk("%s: return %d\n", __func__, ntohl(status));
1514 	return status;
1515 }
1516 
1517 __be32
1518 nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
1519 		  struct nfsd4_setclientid *setclid)
1520 {
1521 	struct sockaddr_in	*sin = svc_addr_in(rqstp);
1522 	struct xdr_netobj 	clname = {
1523 		.len = setclid->se_namelen,
1524 		.data = setclid->se_name,
1525 	};
1526 	nfs4_verifier		clverifier = setclid->se_verf;
1527 	unsigned int 		strhashval;
1528 	struct nfs4_client	*conf, *unconf, *new;
1529 	__be32 			status;
1530 	char			*princ;
1531 	char                    dname[HEXDIR_LEN];
1532 
1533 	if (!check_name(clname))
1534 		return nfserr_inval;
1535 
1536 	status = nfs4_make_rec_clidname(dname, &clname);
1537 	if (status)
1538 		return status;
1539 
1540 	/*
1541 	 * XXX The Duplicate Request Cache (DRC) has been checked (??)
1542 	 * We get here on a DRC miss.
1543 	 */
1544 
1545 	strhashval = clientstr_hashval(dname);
1546 
1547 	nfs4_lock_state();
1548 	conf = find_confirmed_client_by_str(dname, strhashval, false);
1549 	if (conf) {
1550 		/* RFC 3530 14.2.33 CASE 0: */
1551 		status = nfserr_clid_inuse;
1552 		if (!same_creds(&conf->cl_cred, &rqstp->rq_cred)) {
1553 			dprintk("NFSD: setclientid: string in use by client"
1554 				" at %pI4\n", &conf->cl_addr);
1555 			goto out;
1556 		}
1557 	}
1558 	/*
1559 	 * section 14.2.33 of RFC 3530 (under the heading "IMPLEMENTATION")
1560 	 * has a description of SETCLIENTID request processing consisting
1561 	 * of 5 bullet points, labeled as CASE0 - CASE4 below.
1562 	 */
1563 	unconf = find_unconfirmed_client_by_str(dname, strhashval, false);
1564 	status = nfserr_resource;
1565 	if (!conf) {
1566 		/*
1567 		 * RFC 3530 14.2.33 CASE 4:
1568 		 * placed first, because it is the normal case
1569 		 */
1570 		if (unconf)
1571 			expire_client(unconf);
1572 		new = create_client(clname, dname);
1573 		if (new == NULL)
1574 			goto out;
1575 		gen_clid(new);
1576 	} else if (same_verf(&conf->cl_verifier, &clverifier)) {
1577 		/*
1578 		 * RFC 3530 14.2.33 CASE 1:
1579 		 * probable callback update
1580 		 */
1581 		if (unconf) {
1582 			/* Note this is removing unconfirmed {*x***},
1583 			 * which is stronger than RFC recommended {vxc**}.
1584 			 * This has the advantage that there is at most
1585 			 * one {*x***} in either list at any time.
1586 			 */
1587 			expire_client(unconf);
1588 		}
1589 		new = create_client(clname, dname);
1590 		if (new == NULL)
1591 			goto out;
1592 		copy_clid(new, conf);
1593 	} else if (!unconf) {
1594 		/*
1595 		 * RFC 3530 14.2.33 CASE 2:
1596 		 * probable client reboot; state will be removed if
1597 		 * confirmed.
1598 		 */
1599 		new = create_client(clname, dname);
1600 		if (new == NULL)
1601 			goto out;
1602 		gen_clid(new);
1603 	} else {
1604 		/*
1605 		 * RFC 3530 14.2.33 CASE 3:
1606 		 * probable client reboot; state will be removed if
1607 		 * confirmed.
1608 		 */
1609 		expire_client(unconf);
1610 		new = create_client(clname, dname);
1611 		if (new == NULL)
1612 			goto out;
1613 		gen_clid(new);
1614 	}
1615 	copy_verf(new, &clverifier);
1616 	new->cl_addr = sin->sin_addr.s_addr;
1617 	new->cl_flavor = rqstp->rq_flavor;
1618 	princ = svc_gss_principal(rqstp);
1619 	if (princ) {
1620 		new->cl_principal = kstrdup(princ, GFP_KERNEL);
1621 		if (new->cl_principal == NULL) {
1622 			free_client(new);
1623 			goto out;
1624 		}
1625 	}
1626 	copy_cred(&new->cl_cred, &rqstp->rq_cred);
1627 	gen_confirm(new);
1628 	gen_callback(new, setclid);
1629 	add_to_unconfirmed(new, strhashval);
1630 	setclid->se_clientid.cl_boot = new->cl_clientid.cl_boot;
1631 	setclid->se_clientid.cl_id = new->cl_clientid.cl_id;
1632 	memcpy(setclid->se_confirm.data, new->cl_confirm.data, sizeof(setclid->se_confirm.data));
1633 	status = nfs_ok;
1634 out:
1635 	nfs4_unlock_state();
1636 	return status;
1637 }
1638 
1639 
1640 /*
1641  * Section 14.2.34 of RFC 3530 (under the heading "IMPLEMENTATION") has
1642  * a description of SETCLIENTID_CONFIRM request processing consisting of 4
1643  * bullets, labeled as CASE1 - CASE4 below.
1644  */
1645 __be32
1646 nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
1647 			 struct nfsd4_compound_state *cstate,
1648 			 struct nfsd4_setclientid_confirm *setclientid_confirm)
1649 {
1650 	struct sockaddr_in *sin = svc_addr_in(rqstp);
1651 	struct nfs4_client *conf, *unconf;
1652 	nfs4_verifier confirm = setclientid_confirm->sc_confirm;
1653 	clientid_t * clid = &setclientid_confirm->sc_clientid;
1654 	__be32 status;
1655 
1656 	if (STALE_CLIENTID(clid))
1657 		return nfserr_stale_clientid;
1658 	/*
1659 	 * XXX The Duplicate Request Cache (DRC) has been checked (??)
1660 	 * We get here on a DRC miss.
1661 	 */
1662 
1663 	nfs4_lock_state();
1664 
1665 	conf = find_confirmed_client(clid);
1666 	unconf = find_unconfirmed_client(clid);
1667 
1668 	status = nfserr_clid_inuse;
1669 	if (conf && conf->cl_addr != sin->sin_addr.s_addr)
1670 		goto out;
1671 	if (unconf && unconf->cl_addr != sin->sin_addr.s_addr)
1672 		goto out;
1673 
1674 	/*
1675 	 * section 14.2.34 of RFC 3530 has a description of
1676 	 * SETCLIENTID_CONFIRM request processing consisting
1677 	 * of 4 bullet points, labeled as CASE1 - CASE4 below.
1678 	 */
1679 	if (conf && unconf && same_verf(&confirm, &unconf->cl_confirm)) {
1680 		/*
1681 		 * RFC 3530 14.2.34 CASE 1:
1682 		 * callback update
1683 		 */
1684 		if (!same_creds(&conf->cl_cred, &unconf->cl_cred))
1685 			status = nfserr_clid_inuse;
1686 		else {
1687 			/* XXX: We just turn off callbacks until we can handle
1688 			  * change request correctly. */
1689 			atomic_set(&conf->cl_callback.cb_set, 0);
1690 			gen_confirm(conf);
1691 			nfsd4_remove_clid_dir(unconf);
1692 			expire_client(unconf);
1693 			status = nfs_ok;
1694 
1695 		}
1696 	} else if (conf && !unconf) {
1697 		/*
1698 		 * RFC 3530 14.2.34 CASE 2:
1699 		 * probable retransmitted request; play it safe and
1700 		 * do nothing.
1701 		 */
1702 		if (!same_creds(&conf->cl_cred, &rqstp->rq_cred))
1703 			status = nfserr_clid_inuse;
1704 		else
1705 			status = nfs_ok;
1706 	} else if (!conf && unconf
1707 			&& same_verf(&unconf->cl_confirm, &confirm)) {
1708 		/*
1709 		 * RFC 3530 14.2.34 CASE 3:
1710 		 * Normal case; new or rebooted client:
1711 		 */
1712 		if (!same_creds(&unconf->cl_cred, &rqstp->rq_cred)) {
1713 			status = nfserr_clid_inuse;
1714 		} else {
1715 			unsigned int hash =
1716 				clientstr_hashval(unconf->cl_recdir);
1717 			conf = find_confirmed_client_by_str(unconf->cl_recdir,
1718 							    hash, false);
1719 			if (conf) {
1720 				nfsd4_remove_clid_dir(conf);
1721 				expire_client(conf);
1722 			}
1723 			move_to_confirmed(unconf);
1724 			conf = unconf;
1725 			nfsd4_probe_callback(conf);
1726 			status = nfs_ok;
1727 		}
1728 	} else if ((!conf || (conf && !same_verf(&conf->cl_confirm, &confirm)))
1729 	    && (!unconf || (unconf && !same_verf(&unconf->cl_confirm,
1730 				    				&confirm)))) {
1731 		/*
1732 		 * RFC 3530 14.2.34 CASE 4:
1733 		 * Client probably hasn't noticed that we rebooted yet.
1734 		 */
1735 		status = nfserr_stale_clientid;
1736 	} else {
1737 		/* check that we have hit one of the cases...*/
1738 		status = nfserr_clid_inuse;
1739 	}
1740 out:
1741 	nfs4_unlock_state();
1742 	return status;
1743 }
1744 
1745 /* OPEN Share state helper functions */
1746 static inline struct nfs4_file *
1747 alloc_init_file(struct inode *ino)
1748 {
1749 	struct nfs4_file *fp;
1750 	unsigned int hashval = file_hashval(ino);
1751 
1752 	fp = kmem_cache_alloc(file_slab, GFP_KERNEL);
1753 	if (fp) {
1754 		atomic_set(&fp->fi_ref, 1);
1755 		INIT_LIST_HEAD(&fp->fi_hash);
1756 		INIT_LIST_HEAD(&fp->fi_stateids);
1757 		INIT_LIST_HEAD(&fp->fi_delegations);
1758 		spin_lock(&recall_lock);
1759 		list_add(&fp->fi_hash, &file_hashtbl[hashval]);
1760 		spin_unlock(&recall_lock);
1761 		fp->fi_inode = igrab(ino);
1762 		fp->fi_id = current_fileid++;
1763 		fp->fi_had_conflict = false;
1764 		return fp;
1765 	}
1766 	return NULL;
1767 }
1768 
1769 static void
1770 nfsd4_free_slab(struct kmem_cache **slab)
1771 {
1772 	if (*slab == NULL)
1773 		return;
1774 	kmem_cache_destroy(*slab);
1775 	*slab = NULL;
1776 }
1777 
1778 void
1779 nfsd4_free_slabs(void)
1780 {
1781 	nfsd4_free_slab(&stateowner_slab);
1782 	nfsd4_free_slab(&file_slab);
1783 	nfsd4_free_slab(&stateid_slab);
1784 	nfsd4_free_slab(&deleg_slab);
1785 }
1786 
1787 static int
1788 nfsd4_init_slabs(void)
1789 {
1790 	stateowner_slab = kmem_cache_create("nfsd4_stateowners",
1791 			sizeof(struct nfs4_stateowner), 0, 0, NULL);
1792 	if (stateowner_slab == NULL)
1793 		goto out_nomem;
1794 	file_slab = kmem_cache_create("nfsd4_files",
1795 			sizeof(struct nfs4_file), 0, 0, NULL);
1796 	if (file_slab == NULL)
1797 		goto out_nomem;
1798 	stateid_slab = kmem_cache_create("nfsd4_stateids",
1799 			sizeof(struct nfs4_stateid), 0, 0, NULL);
1800 	if (stateid_slab == NULL)
1801 		goto out_nomem;
1802 	deleg_slab = kmem_cache_create("nfsd4_delegations",
1803 			sizeof(struct nfs4_delegation), 0, 0, NULL);
1804 	if (deleg_slab == NULL)
1805 		goto out_nomem;
1806 	return 0;
1807 out_nomem:
1808 	nfsd4_free_slabs();
1809 	dprintk("nfsd4: out of memory while initializing nfsv4\n");
1810 	return -ENOMEM;
1811 }
1812 
1813 void
1814 nfs4_free_stateowner(struct kref *kref)
1815 {
1816 	struct nfs4_stateowner *sop =
1817 		container_of(kref, struct nfs4_stateowner, so_ref);
1818 	kfree(sop->so_owner.data);
1819 	kmem_cache_free(stateowner_slab, sop);
1820 }
1821 
1822 static inline struct nfs4_stateowner *
1823 alloc_stateowner(struct xdr_netobj *owner)
1824 {
1825 	struct nfs4_stateowner *sop;
1826 
1827 	if ((sop = kmem_cache_alloc(stateowner_slab, GFP_KERNEL))) {
1828 		if ((sop->so_owner.data = kmalloc(owner->len, GFP_KERNEL))) {
1829 			memcpy(sop->so_owner.data, owner->data, owner->len);
1830 			sop->so_owner.len = owner->len;
1831 			kref_init(&sop->so_ref);
1832 			return sop;
1833 		}
1834 		kmem_cache_free(stateowner_slab, sop);
1835 	}
1836 	return NULL;
1837 }
1838 
1839 static struct nfs4_stateowner *
1840 alloc_init_open_stateowner(unsigned int strhashval, struct nfs4_client *clp, struct nfsd4_open *open) {
1841 	struct nfs4_stateowner *sop;
1842 	struct nfs4_replay *rp;
1843 	unsigned int idhashval;
1844 
1845 	if (!(sop = alloc_stateowner(&open->op_owner)))
1846 		return NULL;
1847 	idhashval = ownerid_hashval(current_ownerid);
1848 	INIT_LIST_HEAD(&sop->so_idhash);
1849 	INIT_LIST_HEAD(&sop->so_strhash);
1850 	INIT_LIST_HEAD(&sop->so_perclient);
1851 	INIT_LIST_HEAD(&sop->so_stateids);
1852 	INIT_LIST_HEAD(&sop->so_perstateid);  /* not used */
1853 	INIT_LIST_HEAD(&sop->so_close_lru);
1854 	sop->so_time = 0;
1855 	list_add(&sop->so_idhash, &ownerid_hashtbl[idhashval]);
1856 	list_add(&sop->so_strhash, &ownerstr_hashtbl[strhashval]);
1857 	list_add(&sop->so_perclient, &clp->cl_openowners);
1858 	sop->so_is_open_owner = 1;
1859 	sop->so_id = current_ownerid++;
1860 	sop->so_client = clp;
1861 	sop->so_seqid = open->op_seqid;
1862 	sop->so_confirmed = 0;
1863 	rp = &sop->so_replay;
1864 	rp->rp_status = nfserr_serverfault;
1865 	rp->rp_buflen = 0;
1866 	rp->rp_buf = rp->rp_ibuf;
1867 	return sop;
1868 }
1869 
1870 static inline void
1871 init_stateid(struct nfs4_stateid *stp, struct nfs4_file *fp, struct nfsd4_open *open) {
1872 	struct nfs4_stateowner *sop = open->op_stateowner;
1873 	unsigned int hashval = stateid_hashval(sop->so_id, fp->fi_id);
1874 
1875 	INIT_LIST_HEAD(&stp->st_hash);
1876 	INIT_LIST_HEAD(&stp->st_perstateowner);
1877 	INIT_LIST_HEAD(&stp->st_lockowners);
1878 	INIT_LIST_HEAD(&stp->st_perfile);
1879 	list_add(&stp->st_hash, &stateid_hashtbl[hashval]);
1880 	list_add(&stp->st_perstateowner, &sop->so_stateids);
1881 	list_add(&stp->st_perfile, &fp->fi_stateids);
1882 	stp->st_stateowner = sop;
1883 	get_nfs4_file(fp);
1884 	stp->st_file = fp;
1885 	stp->st_stateid.si_boot = boot_time;
1886 	stp->st_stateid.si_stateownerid = sop->so_id;
1887 	stp->st_stateid.si_fileid = fp->fi_id;
1888 	stp->st_stateid.si_generation = 0;
1889 	stp->st_access_bmap = 0;
1890 	stp->st_deny_bmap = 0;
1891 	__set_bit(open->op_share_access & ~NFS4_SHARE_WANT_MASK,
1892 		  &stp->st_access_bmap);
1893 	__set_bit(open->op_share_deny, &stp->st_deny_bmap);
1894 	stp->st_openstp = NULL;
1895 }
1896 
1897 static void
1898 move_to_close_lru(struct nfs4_stateowner *sop)
1899 {
1900 	dprintk("NFSD: move_to_close_lru nfs4_stateowner %p\n", sop);
1901 
1902 	list_move_tail(&sop->so_close_lru, &close_lru);
1903 	sop->so_time = get_seconds();
1904 }
1905 
1906 static int
1907 same_owner_str(struct nfs4_stateowner *sop, struct xdr_netobj *owner,
1908 							clientid_t *clid)
1909 {
1910 	return (sop->so_owner.len == owner->len) &&
1911 		0 == memcmp(sop->so_owner.data, owner->data, owner->len) &&
1912 		(sop->so_client->cl_clientid.cl_id == clid->cl_id);
1913 }
1914 
1915 static struct nfs4_stateowner *
1916 find_openstateowner_str(unsigned int hashval, struct nfsd4_open *open)
1917 {
1918 	struct nfs4_stateowner *so = NULL;
1919 
1920 	list_for_each_entry(so, &ownerstr_hashtbl[hashval], so_strhash) {
1921 		if (same_owner_str(so, &open->op_owner, &open->op_clientid))
1922 			return so;
1923 	}
1924 	return NULL;
1925 }
1926 
1927 /* search file_hashtbl[] for file */
1928 static struct nfs4_file *
1929 find_file(struct inode *ino)
1930 {
1931 	unsigned int hashval = file_hashval(ino);
1932 	struct nfs4_file *fp;
1933 
1934 	spin_lock(&recall_lock);
1935 	list_for_each_entry(fp, &file_hashtbl[hashval], fi_hash) {
1936 		if (fp->fi_inode == ino) {
1937 			get_nfs4_file(fp);
1938 			spin_unlock(&recall_lock);
1939 			return fp;
1940 		}
1941 	}
1942 	spin_unlock(&recall_lock);
1943 	return NULL;
1944 }
1945 
1946 static inline int access_valid(u32 x, u32 minorversion)
1947 {
1948 	if ((x & NFS4_SHARE_ACCESS_MASK) < NFS4_SHARE_ACCESS_READ)
1949 		return 0;
1950 	if ((x & NFS4_SHARE_ACCESS_MASK) > NFS4_SHARE_ACCESS_BOTH)
1951 		return 0;
1952 	x &= ~NFS4_SHARE_ACCESS_MASK;
1953 	if (minorversion && x) {
1954 		if ((x & NFS4_SHARE_WANT_MASK) > NFS4_SHARE_WANT_CANCEL)
1955 			return 0;
1956 		if ((x & NFS4_SHARE_WHEN_MASK) > NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED)
1957 			return 0;
1958 		x &= ~(NFS4_SHARE_WANT_MASK | NFS4_SHARE_WHEN_MASK);
1959 	}
1960 	if (x)
1961 		return 0;
1962 	return 1;
1963 }
1964 
1965 static inline int deny_valid(u32 x)
1966 {
1967 	/* Note: unlike access bits, deny bits may be zero. */
1968 	return x <= NFS4_SHARE_DENY_BOTH;
1969 }
1970 
1971 /*
1972  * We store the NONE, READ, WRITE, and BOTH bits separately in the
1973  * st_{access,deny}_bmap field of the stateid, in order to track not
1974  * only what share bits are currently in force, but also what
1975  * combinations of share bits previous opens have used.  This allows us
1976  * to enforce the recommendation of rfc 3530 14.2.19 that the server
1977  * return an error if the client attempt to downgrade to a combination
1978  * of share bits not explicable by closing some of its previous opens.
1979  *
1980  * XXX: This enforcement is actually incomplete, since we don't keep
1981  * track of access/deny bit combinations; so, e.g., we allow:
1982  *
1983  *	OPEN allow read, deny write
1984  *	OPEN allow both, deny none
1985  *	DOWNGRADE allow read, deny none
1986  *
1987  * which we should reject.
1988  */
1989 static void
1990 set_access(unsigned int *access, unsigned long bmap) {
1991 	int i;
1992 
1993 	*access = 0;
1994 	for (i = 1; i < 4; i++) {
1995 		if (test_bit(i, &bmap))
1996 			*access |= i;
1997 	}
1998 }
1999 
2000 static void
2001 set_deny(unsigned int *deny, unsigned long bmap) {
2002 	int i;
2003 
2004 	*deny = 0;
2005 	for (i = 0; i < 4; i++) {
2006 		if (test_bit(i, &bmap))
2007 			*deny |= i ;
2008 	}
2009 }
2010 
2011 static int
2012 test_share(struct nfs4_stateid *stp, struct nfsd4_open *open) {
2013 	unsigned int access, deny;
2014 
2015 	set_access(&access, stp->st_access_bmap);
2016 	set_deny(&deny, stp->st_deny_bmap);
2017 	if ((access & open->op_share_deny) || (deny & open->op_share_access))
2018 		return 0;
2019 	return 1;
2020 }
2021 
2022 /*
2023  * Called to check deny when READ with all zero stateid or
2024  * WRITE with all zero or all one stateid
2025  */
2026 static __be32
2027 nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type)
2028 {
2029 	struct inode *ino = current_fh->fh_dentry->d_inode;
2030 	struct nfs4_file *fp;
2031 	struct nfs4_stateid *stp;
2032 	__be32 ret;
2033 
2034 	dprintk("NFSD: nfs4_share_conflict\n");
2035 
2036 	fp = find_file(ino);
2037 	if (!fp)
2038 		return nfs_ok;
2039 	ret = nfserr_locked;
2040 	/* Search for conflicting share reservations */
2041 	list_for_each_entry(stp, &fp->fi_stateids, st_perfile) {
2042 		if (test_bit(deny_type, &stp->st_deny_bmap) ||
2043 		    test_bit(NFS4_SHARE_DENY_BOTH, &stp->st_deny_bmap))
2044 			goto out;
2045 	}
2046 	ret = nfs_ok;
2047 out:
2048 	put_nfs4_file(fp);
2049 	return ret;
2050 }
2051 
2052 static inline void
2053 nfs4_file_downgrade(struct file *filp, unsigned int share_access)
2054 {
2055 	if (share_access & NFS4_SHARE_ACCESS_WRITE) {
2056 		drop_file_write_access(filp);
2057 		filp->f_mode = (filp->f_mode | FMODE_READ) & ~FMODE_WRITE;
2058 	}
2059 }
2060 
2061 /*
2062  * Recall a delegation
2063  */
2064 static int
2065 do_recall(void *__dp)
2066 {
2067 	struct nfs4_delegation *dp = __dp;
2068 
2069 	dp->dl_file->fi_had_conflict = true;
2070 	nfsd4_cb_recall(dp);
2071 	return 0;
2072 }
2073 
2074 /*
2075  * Spawn a thread to perform a recall on the delegation represented
2076  * by the lease (file_lock)
2077  *
2078  * Called from break_lease() with lock_kernel() held.
2079  * Note: we assume break_lease will only call this *once* for any given
2080  * lease.
2081  */
2082 static
2083 void nfsd_break_deleg_cb(struct file_lock *fl)
2084 {
2085 	struct nfs4_delegation *dp=  (struct nfs4_delegation *)fl->fl_owner;
2086 	struct task_struct *t;
2087 
2088 	dprintk("NFSD nfsd_break_deleg_cb: dp %p fl %p\n",dp,fl);
2089 	if (!dp)
2090 		return;
2091 
2092 	/* We're assuming the state code never drops its reference
2093 	 * without first removing the lease.  Since we're in this lease
2094 	 * callback (and since the lease code is serialized by the kernel
2095 	 * lock) we know the server hasn't removed the lease yet, we know
2096 	 * it's safe to take a reference: */
2097 	atomic_inc(&dp->dl_count);
2098 	atomic_inc(&dp->dl_client->cl_count);
2099 
2100 	spin_lock(&recall_lock);
2101 	list_add_tail(&dp->dl_recall_lru, &del_recall_lru);
2102 	spin_unlock(&recall_lock);
2103 
2104 	/* only place dl_time is set. protected by lock_kernel*/
2105 	dp->dl_time = get_seconds();
2106 
2107 	/*
2108 	 * We don't want the locks code to timeout the lease for us;
2109 	 * we'll remove it ourself if the delegation isn't returned
2110 	 * in time.
2111 	 */
2112 	fl->fl_break_time = 0;
2113 
2114 	t = kthread_run(do_recall, dp, "%s", "nfs4_cb_recall");
2115 	if (IS_ERR(t)) {
2116 		struct nfs4_client *clp = dp->dl_client;
2117 
2118 		printk(KERN_INFO "NFSD: Callback thread failed for "
2119 			"for client (clientid %08x/%08x)\n",
2120 			clp->cl_clientid.cl_boot, clp->cl_clientid.cl_id);
2121 		put_nfs4_client(dp->dl_client);
2122 		nfs4_put_delegation(dp);
2123 	}
2124 }
2125 
2126 /*
2127  * The file_lock is being reapd.
2128  *
2129  * Called by locks_free_lock() with lock_kernel() held.
2130  */
2131 static
2132 void nfsd_release_deleg_cb(struct file_lock *fl)
2133 {
2134 	struct nfs4_delegation *dp = (struct nfs4_delegation *)fl->fl_owner;
2135 
2136 	dprintk("NFSD nfsd_release_deleg_cb: fl %p dp %p dl_count %d\n", fl,dp, atomic_read(&dp->dl_count));
2137 
2138 	if (!(fl->fl_flags & FL_LEASE) || !dp)
2139 		return;
2140 	dp->dl_flock = NULL;
2141 }
2142 
2143 /*
2144  * Set the delegation file_lock back pointer.
2145  *
2146  * Called from setlease() with lock_kernel() held.
2147  */
2148 static
2149 void nfsd_copy_lock_deleg_cb(struct file_lock *new, struct file_lock *fl)
2150 {
2151 	struct nfs4_delegation *dp = (struct nfs4_delegation *)new->fl_owner;
2152 
2153 	dprintk("NFSD: nfsd_copy_lock_deleg_cb: new fl %p dp %p\n", new, dp);
2154 	if (!dp)
2155 		return;
2156 	dp->dl_flock = new;
2157 }
2158 
2159 /*
2160  * Called from setlease() with lock_kernel() held
2161  */
2162 static
2163 int nfsd_same_client_deleg_cb(struct file_lock *onlist, struct file_lock *try)
2164 {
2165 	struct nfs4_delegation *onlistd =
2166 		(struct nfs4_delegation *)onlist->fl_owner;
2167 	struct nfs4_delegation *tryd =
2168 		(struct nfs4_delegation *)try->fl_owner;
2169 
2170 	if (onlist->fl_lmops != try->fl_lmops)
2171 		return 0;
2172 
2173 	return onlistd->dl_client == tryd->dl_client;
2174 }
2175 
2176 
2177 static
2178 int nfsd_change_deleg_cb(struct file_lock **onlist, int arg)
2179 {
2180 	if (arg & F_UNLCK)
2181 		return lease_modify(onlist, arg);
2182 	else
2183 		return -EAGAIN;
2184 }
2185 
2186 static struct lock_manager_operations nfsd_lease_mng_ops = {
2187 	.fl_break = nfsd_break_deleg_cb,
2188 	.fl_release_private = nfsd_release_deleg_cb,
2189 	.fl_copy_lock = nfsd_copy_lock_deleg_cb,
2190 	.fl_mylease = nfsd_same_client_deleg_cb,
2191 	.fl_change = nfsd_change_deleg_cb,
2192 };
2193 
2194 
2195 __be32
2196 nfsd4_process_open1(struct nfsd4_compound_state *cstate,
2197 		    struct nfsd4_open *open)
2198 {
2199 	clientid_t *clientid = &open->op_clientid;
2200 	struct nfs4_client *clp = NULL;
2201 	unsigned int strhashval;
2202 	struct nfs4_stateowner *sop = NULL;
2203 
2204 	if (!check_name(open->op_owner))
2205 		return nfserr_inval;
2206 
2207 	if (STALE_CLIENTID(&open->op_clientid))
2208 		return nfserr_stale_clientid;
2209 
2210 	strhashval = ownerstr_hashval(clientid->cl_id, open->op_owner);
2211 	sop = find_openstateowner_str(strhashval, open);
2212 	open->op_stateowner = sop;
2213 	if (!sop) {
2214 		/* Make sure the client's lease hasn't expired. */
2215 		clp = find_confirmed_client(clientid);
2216 		if (clp == NULL)
2217 			return nfserr_expired;
2218 		goto renew;
2219 	}
2220 	/* When sessions are used, skip open sequenceid processing */
2221 	if (nfsd4_has_session(cstate))
2222 		goto renew;
2223 	if (!sop->so_confirmed) {
2224 		/* Replace unconfirmed owners without checking for replay. */
2225 		clp = sop->so_client;
2226 		release_openowner(sop);
2227 		open->op_stateowner = NULL;
2228 		goto renew;
2229 	}
2230 	if (open->op_seqid == sop->so_seqid - 1) {
2231 		if (sop->so_replay.rp_buflen)
2232 			return nfserr_replay_me;
2233 		/* The original OPEN failed so spectacularly
2234 		 * that we don't even have replay data saved!
2235 		 * Therefore, we have no choice but to continue
2236 		 * processing this OPEN; presumably, we'll
2237 		 * fail again for the same reason.
2238 		 */
2239 		dprintk("nfsd4_process_open1: replay with no replay cache\n");
2240 		goto renew;
2241 	}
2242 	if (open->op_seqid != sop->so_seqid)
2243 		return nfserr_bad_seqid;
2244 renew:
2245 	if (open->op_stateowner == NULL) {
2246 		sop = alloc_init_open_stateowner(strhashval, clp, open);
2247 		if (sop == NULL)
2248 			return nfserr_resource;
2249 		open->op_stateowner = sop;
2250 	}
2251 	list_del_init(&sop->so_close_lru);
2252 	renew_client(sop->so_client);
2253 	return nfs_ok;
2254 }
2255 
2256 static inline __be32
2257 nfs4_check_delegmode(struct nfs4_delegation *dp, int flags)
2258 {
2259 	if ((flags & WR_STATE) && (dp->dl_type == NFS4_OPEN_DELEGATE_READ))
2260 		return nfserr_openmode;
2261 	else
2262 		return nfs_ok;
2263 }
2264 
2265 static struct nfs4_delegation *
2266 find_delegation_file(struct nfs4_file *fp, stateid_t *stid)
2267 {
2268 	struct nfs4_delegation *dp;
2269 
2270 	list_for_each_entry(dp, &fp->fi_delegations, dl_perfile) {
2271 		if (dp->dl_stateid.si_stateownerid == stid->si_stateownerid)
2272 			return dp;
2273 	}
2274 	return NULL;
2275 }
2276 
2277 static __be32
2278 nfs4_check_deleg(struct nfs4_file *fp, struct nfsd4_open *open,
2279 		struct nfs4_delegation **dp)
2280 {
2281 	int flags;
2282 	__be32 status = nfserr_bad_stateid;
2283 
2284 	*dp = find_delegation_file(fp, &open->op_delegate_stateid);
2285 	if (*dp == NULL)
2286 		goto out;
2287 	flags = open->op_share_access == NFS4_SHARE_ACCESS_READ ?
2288 						RD_STATE : WR_STATE;
2289 	status = nfs4_check_delegmode(*dp, flags);
2290 	if (status)
2291 		*dp = NULL;
2292 out:
2293 	if (open->op_claim_type != NFS4_OPEN_CLAIM_DELEGATE_CUR)
2294 		return nfs_ok;
2295 	if (status)
2296 		return status;
2297 	open->op_stateowner->so_confirmed = 1;
2298 	return nfs_ok;
2299 }
2300 
2301 static __be32
2302 nfs4_check_open(struct nfs4_file *fp, struct nfsd4_open *open, struct nfs4_stateid **stpp)
2303 {
2304 	struct nfs4_stateid *local;
2305 	__be32 status = nfserr_share_denied;
2306 	struct nfs4_stateowner *sop = open->op_stateowner;
2307 
2308 	list_for_each_entry(local, &fp->fi_stateids, st_perfile) {
2309 		/* ignore lock owners */
2310 		if (local->st_stateowner->so_is_open_owner == 0)
2311 			continue;
2312 		/* remember if we have seen this open owner */
2313 		if (local->st_stateowner == sop)
2314 			*stpp = local;
2315 		/* check for conflicting share reservations */
2316 		if (!test_share(local, open))
2317 			goto out;
2318 	}
2319 	status = 0;
2320 out:
2321 	return status;
2322 }
2323 
2324 static inline struct nfs4_stateid *
2325 nfs4_alloc_stateid(void)
2326 {
2327 	return kmem_cache_alloc(stateid_slab, GFP_KERNEL);
2328 }
2329 
2330 static __be32
2331 nfs4_new_open(struct svc_rqst *rqstp, struct nfs4_stateid **stpp,
2332 		struct nfs4_delegation *dp,
2333 		struct svc_fh *cur_fh, int flags)
2334 {
2335 	struct nfs4_stateid *stp;
2336 
2337 	stp = nfs4_alloc_stateid();
2338 	if (stp == NULL)
2339 		return nfserr_resource;
2340 
2341 	if (dp) {
2342 		get_file(dp->dl_vfs_file);
2343 		stp->st_vfs_file = dp->dl_vfs_file;
2344 	} else {
2345 		__be32 status;
2346 		status = nfsd_open(rqstp, cur_fh, S_IFREG, flags,
2347 				&stp->st_vfs_file);
2348 		if (status) {
2349 			if (status == nfserr_dropit)
2350 				status = nfserr_jukebox;
2351 			kmem_cache_free(stateid_slab, stp);
2352 			return status;
2353 		}
2354 	}
2355 	*stpp = stp;
2356 	return 0;
2357 }
2358 
2359 static inline __be32
2360 nfsd4_truncate(struct svc_rqst *rqstp, struct svc_fh *fh,
2361 		struct nfsd4_open *open)
2362 {
2363 	struct iattr iattr = {
2364 		.ia_valid = ATTR_SIZE,
2365 		.ia_size = 0,
2366 	};
2367 	if (!open->op_truncate)
2368 		return 0;
2369 	if (!(open->op_share_access & NFS4_SHARE_ACCESS_WRITE))
2370 		return nfserr_inval;
2371 	return nfsd_setattr(rqstp, fh, &iattr, 0, (time_t)0);
2372 }
2373 
2374 static __be32
2375 nfs4_upgrade_open(struct svc_rqst *rqstp, struct svc_fh *cur_fh, struct nfs4_stateid *stp, struct nfsd4_open *open)
2376 {
2377 	struct file *filp = stp->st_vfs_file;
2378 	struct inode *inode = filp->f_path.dentry->d_inode;
2379 	unsigned int share_access, new_writer;
2380 	__be32 status;
2381 
2382 	set_access(&share_access, stp->st_access_bmap);
2383 	new_writer = (~share_access) & open->op_share_access
2384 			& NFS4_SHARE_ACCESS_WRITE;
2385 
2386 	if (new_writer) {
2387 		int err = get_write_access(inode);
2388 		if (err)
2389 			return nfserrno(err);
2390 		err = mnt_want_write(cur_fh->fh_export->ex_path.mnt);
2391 		if (err)
2392 			return nfserrno(err);
2393 		file_take_write(filp);
2394 	}
2395 	status = nfsd4_truncate(rqstp, cur_fh, open);
2396 	if (status) {
2397 		if (new_writer)
2398 			put_write_access(inode);
2399 		return status;
2400 	}
2401 	/* remember the open */
2402 	filp->f_mode |= open->op_share_access;
2403 	__set_bit(open->op_share_access, &stp->st_access_bmap);
2404 	__set_bit(open->op_share_deny, &stp->st_deny_bmap);
2405 
2406 	return nfs_ok;
2407 }
2408 
2409 
2410 static void
2411 nfs4_set_claim_prev(struct nfsd4_open *open)
2412 {
2413 	open->op_stateowner->so_confirmed = 1;
2414 	open->op_stateowner->so_client->cl_firststate = 1;
2415 }
2416 
2417 /*
2418  * Attempt to hand out a delegation.
2419  */
2420 static void
2421 nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_stateid *stp)
2422 {
2423 	struct nfs4_delegation *dp;
2424 	struct nfs4_stateowner *sop = stp->st_stateowner;
2425 	struct nfs4_callback *cb = &sop->so_client->cl_callback;
2426 	struct file_lock fl, *flp = &fl;
2427 	int status, flag = 0;
2428 
2429 	flag = NFS4_OPEN_DELEGATE_NONE;
2430 	open->op_recall = 0;
2431 	switch (open->op_claim_type) {
2432 		case NFS4_OPEN_CLAIM_PREVIOUS:
2433 			if (!atomic_read(&cb->cb_set))
2434 				open->op_recall = 1;
2435 			flag = open->op_delegate_type;
2436 			if (flag == NFS4_OPEN_DELEGATE_NONE)
2437 				goto out;
2438 			break;
2439 		case NFS4_OPEN_CLAIM_NULL:
2440 			/* Let's not give out any delegations till everyone's
2441 			 * had the chance to reclaim theirs.... */
2442 			if (locks_in_grace())
2443 				goto out;
2444 			if (!atomic_read(&cb->cb_set) || !sop->so_confirmed)
2445 				goto out;
2446 			if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
2447 				flag = NFS4_OPEN_DELEGATE_WRITE;
2448 			else
2449 				flag = NFS4_OPEN_DELEGATE_READ;
2450 			break;
2451 		default:
2452 			goto out;
2453 	}
2454 
2455 	dp = alloc_init_deleg(sop->so_client, stp, fh, flag);
2456 	if (dp == NULL) {
2457 		flag = NFS4_OPEN_DELEGATE_NONE;
2458 		goto out;
2459 	}
2460 	locks_init_lock(&fl);
2461 	fl.fl_lmops = &nfsd_lease_mng_ops;
2462 	fl.fl_flags = FL_LEASE;
2463 	fl.fl_type = flag == NFS4_OPEN_DELEGATE_READ? F_RDLCK: F_WRLCK;
2464 	fl.fl_end = OFFSET_MAX;
2465 	fl.fl_owner =  (fl_owner_t)dp;
2466 	fl.fl_file = stp->st_vfs_file;
2467 	fl.fl_pid = current->tgid;
2468 
2469 	/* vfs_setlease checks to see if delegation should be handed out.
2470 	 * the lock_manager callbacks fl_mylease and fl_change are used
2471 	 */
2472 	if ((status = vfs_setlease(stp->st_vfs_file, fl.fl_type, &flp))) {
2473 		dprintk("NFSD: setlease failed [%d], no delegation\n", status);
2474 		unhash_delegation(dp);
2475 		flag = NFS4_OPEN_DELEGATE_NONE;
2476 		goto out;
2477 	}
2478 
2479 	memcpy(&open->op_delegate_stateid, &dp->dl_stateid, sizeof(dp->dl_stateid));
2480 
2481 	dprintk("NFSD: delegation stateid=(%08x/%08x/%08x/%08x)\n\n",
2482 	             dp->dl_stateid.si_boot,
2483 	             dp->dl_stateid.si_stateownerid,
2484 	             dp->dl_stateid.si_fileid,
2485 	             dp->dl_stateid.si_generation);
2486 out:
2487 	if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS
2488 			&& flag == NFS4_OPEN_DELEGATE_NONE
2489 			&& open->op_delegate_type != NFS4_OPEN_DELEGATE_NONE)
2490 		dprintk("NFSD: WARNING: refusing delegation reclaim\n");
2491 	open->op_delegate_type = flag;
2492 }
2493 
2494 /*
2495  * called with nfs4_lock_state() held.
2496  */
2497 __be32
2498 nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
2499 {
2500 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2501 	struct nfs4_file *fp = NULL;
2502 	struct inode *ino = current_fh->fh_dentry->d_inode;
2503 	struct nfs4_stateid *stp = NULL;
2504 	struct nfs4_delegation *dp = NULL;
2505 	__be32 status;
2506 
2507 	status = nfserr_inval;
2508 	if (!access_valid(open->op_share_access, resp->cstate.minorversion)
2509 			|| !deny_valid(open->op_share_deny))
2510 		goto out;
2511 	/*
2512 	 * Lookup file; if found, lookup stateid and check open request,
2513 	 * and check for delegations in the process of being recalled.
2514 	 * If not found, create the nfs4_file struct
2515 	 */
2516 	fp = find_file(ino);
2517 	if (fp) {
2518 		if ((status = nfs4_check_open(fp, open, &stp)))
2519 			goto out;
2520 		status = nfs4_check_deleg(fp, open, &dp);
2521 		if (status)
2522 			goto out;
2523 	} else {
2524 		status = nfserr_bad_stateid;
2525 		if (open->op_claim_type == NFS4_OPEN_CLAIM_DELEGATE_CUR)
2526 			goto out;
2527 		status = nfserr_resource;
2528 		fp = alloc_init_file(ino);
2529 		if (fp == NULL)
2530 			goto out;
2531 	}
2532 
2533 	/*
2534 	 * OPEN the file, or upgrade an existing OPEN.
2535 	 * If truncate fails, the OPEN fails.
2536 	 */
2537 	if (stp) {
2538 		/* Stateid was found, this is an OPEN upgrade */
2539 		status = nfs4_upgrade_open(rqstp, current_fh, stp, open);
2540 		if (status)
2541 			goto out;
2542 		update_stateid(&stp->st_stateid);
2543 	} else {
2544 		/* Stateid was not found, this is a new OPEN */
2545 		int flags = 0;
2546 		if (open->op_share_access & NFS4_SHARE_ACCESS_READ)
2547 			flags |= NFSD_MAY_READ;
2548 		if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
2549 			flags |= NFSD_MAY_WRITE;
2550 		status = nfs4_new_open(rqstp, &stp, dp, current_fh, flags);
2551 		if (status)
2552 			goto out;
2553 		init_stateid(stp, fp, open);
2554 		status = nfsd4_truncate(rqstp, current_fh, open);
2555 		if (status) {
2556 			release_open_stateid(stp);
2557 			goto out;
2558 		}
2559 		if (nfsd4_has_session(&resp->cstate))
2560 			update_stateid(&stp->st_stateid);
2561 	}
2562 	memcpy(&open->op_stateid, &stp->st_stateid, sizeof(stateid_t));
2563 
2564 	if (nfsd4_has_session(&resp->cstate))
2565 		open->op_stateowner->so_confirmed = 1;
2566 
2567 	/*
2568 	* Attempt to hand out a delegation. No error return, because the
2569 	* OPEN succeeds even if we fail.
2570 	*/
2571 	nfs4_open_delegation(current_fh, open, stp);
2572 
2573 	status = nfs_ok;
2574 
2575 	dprintk("nfs4_process_open2: stateid=(%08x/%08x/%08x/%08x)\n",
2576 	            stp->st_stateid.si_boot, stp->st_stateid.si_stateownerid,
2577 	            stp->st_stateid.si_fileid, stp->st_stateid.si_generation);
2578 out:
2579 	if (fp)
2580 		put_nfs4_file(fp);
2581 	if (status == 0 && open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS)
2582 		nfs4_set_claim_prev(open);
2583 	/*
2584 	* To finish the open response, we just need to set the rflags.
2585 	*/
2586 	open->op_rflags = NFS4_OPEN_RESULT_LOCKTYPE_POSIX;
2587 	if (!open->op_stateowner->so_confirmed &&
2588 	    !nfsd4_has_session(&resp->cstate))
2589 		open->op_rflags |= NFS4_OPEN_RESULT_CONFIRM;
2590 
2591 	return status;
2592 }
2593 
2594 __be32
2595 nfsd4_renew(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
2596 	    clientid_t *clid)
2597 {
2598 	struct nfs4_client *clp;
2599 	__be32 status;
2600 
2601 	nfs4_lock_state();
2602 	dprintk("process_renew(%08x/%08x): starting\n",
2603 			clid->cl_boot, clid->cl_id);
2604 	status = nfserr_stale_clientid;
2605 	if (STALE_CLIENTID(clid))
2606 		goto out;
2607 	clp = find_confirmed_client(clid);
2608 	status = nfserr_expired;
2609 	if (clp == NULL) {
2610 		/* We assume the client took too long to RENEW. */
2611 		dprintk("nfsd4_renew: clientid not found!\n");
2612 		goto out;
2613 	}
2614 	renew_client(clp);
2615 	status = nfserr_cb_path_down;
2616 	if (!list_empty(&clp->cl_delegations)
2617 			&& !atomic_read(&clp->cl_callback.cb_set))
2618 		goto out;
2619 	status = nfs_ok;
2620 out:
2621 	nfs4_unlock_state();
2622 	return status;
2623 }
2624 
2625 struct lock_manager nfsd4_manager = {
2626 };
2627 
2628 static void
2629 nfsd4_end_grace(void)
2630 {
2631 	dprintk("NFSD: end of grace period\n");
2632 	nfsd4_recdir_purge_old();
2633 	locks_end_grace(&nfsd4_manager);
2634 }
2635 
2636 static time_t
2637 nfs4_laundromat(void)
2638 {
2639 	struct nfs4_client *clp;
2640 	struct nfs4_stateowner *sop;
2641 	struct nfs4_delegation *dp;
2642 	struct list_head *pos, *next, reaplist;
2643 	time_t cutoff = get_seconds() - NFSD_LEASE_TIME;
2644 	time_t t, clientid_val = NFSD_LEASE_TIME;
2645 	time_t u, test_val = NFSD_LEASE_TIME;
2646 
2647 	nfs4_lock_state();
2648 
2649 	dprintk("NFSD: laundromat service - starting\n");
2650 	if (locks_in_grace())
2651 		nfsd4_end_grace();
2652 	list_for_each_safe(pos, next, &client_lru) {
2653 		clp = list_entry(pos, struct nfs4_client, cl_lru);
2654 		if (time_after((unsigned long)clp->cl_time, (unsigned long)cutoff)) {
2655 			t = clp->cl_time - cutoff;
2656 			if (clientid_val > t)
2657 				clientid_val = t;
2658 			break;
2659 		}
2660 		dprintk("NFSD: purging unused client (clientid %08x)\n",
2661 			clp->cl_clientid.cl_id);
2662 		nfsd4_remove_clid_dir(clp);
2663 		expire_client(clp);
2664 	}
2665 	INIT_LIST_HEAD(&reaplist);
2666 	spin_lock(&recall_lock);
2667 	list_for_each_safe(pos, next, &del_recall_lru) {
2668 		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
2669 		if (time_after((unsigned long)dp->dl_time, (unsigned long)cutoff)) {
2670 			u = dp->dl_time - cutoff;
2671 			if (test_val > u)
2672 				test_val = u;
2673 			break;
2674 		}
2675 		dprintk("NFSD: purging unused delegation dp %p, fp %p\n",
2676 			            dp, dp->dl_flock);
2677 		list_move(&dp->dl_recall_lru, &reaplist);
2678 	}
2679 	spin_unlock(&recall_lock);
2680 	list_for_each_safe(pos, next, &reaplist) {
2681 		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
2682 		list_del_init(&dp->dl_recall_lru);
2683 		unhash_delegation(dp);
2684 	}
2685 	test_val = NFSD_LEASE_TIME;
2686 	list_for_each_safe(pos, next, &close_lru) {
2687 		sop = list_entry(pos, struct nfs4_stateowner, so_close_lru);
2688 		if (time_after((unsigned long)sop->so_time, (unsigned long)cutoff)) {
2689 			u = sop->so_time - cutoff;
2690 			if (test_val > u)
2691 				test_val = u;
2692 			break;
2693 		}
2694 		dprintk("NFSD: purging unused open stateowner (so_id %d)\n",
2695 			sop->so_id);
2696 		release_openowner(sop);
2697 	}
2698 	if (clientid_val < NFSD_LAUNDROMAT_MINTIMEOUT)
2699 		clientid_val = NFSD_LAUNDROMAT_MINTIMEOUT;
2700 	nfs4_unlock_state();
2701 	return clientid_val;
2702 }
2703 
2704 static struct workqueue_struct *laundry_wq;
2705 static void laundromat_main(struct work_struct *);
2706 static DECLARE_DELAYED_WORK(laundromat_work, laundromat_main);
2707 
2708 static void
2709 laundromat_main(struct work_struct *not_used)
2710 {
2711 	time_t t;
2712 
2713 	t = nfs4_laundromat();
2714 	dprintk("NFSD: laundromat_main - sleeping for %ld seconds\n", t);
2715 	queue_delayed_work(laundry_wq, &laundromat_work, t*HZ);
2716 }
2717 
2718 static struct nfs4_stateowner *
2719 search_close_lru(u32 st_id, int flags)
2720 {
2721 	struct nfs4_stateowner *local = NULL;
2722 
2723 	if (flags & CLOSE_STATE) {
2724 		list_for_each_entry(local, &close_lru, so_close_lru) {
2725 			if (local->so_id == st_id)
2726 				return local;
2727 		}
2728 	}
2729 	return NULL;
2730 }
2731 
2732 static inline int
2733 nfs4_check_fh(struct svc_fh *fhp, struct nfs4_stateid *stp)
2734 {
2735 	return fhp->fh_dentry->d_inode != stp->st_vfs_file->f_path.dentry->d_inode;
2736 }
2737 
2738 static int
2739 STALE_STATEID(stateid_t *stateid)
2740 {
2741 	if (stateid->si_boot == boot_time)
2742 		return 0;
2743 	dprintk("NFSD: stale stateid (%08x/%08x/%08x/%08x)!\n",
2744 		stateid->si_boot, stateid->si_stateownerid, stateid->si_fileid,
2745 		stateid->si_generation);
2746 	return 1;
2747 }
2748 
2749 static inline int
2750 access_permit_read(unsigned long access_bmap)
2751 {
2752 	return test_bit(NFS4_SHARE_ACCESS_READ, &access_bmap) ||
2753 		test_bit(NFS4_SHARE_ACCESS_BOTH, &access_bmap) ||
2754 		test_bit(NFS4_SHARE_ACCESS_WRITE, &access_bmap);
2755 }
2756 
2757 static inline int
2758 access_permit_write(unsigned long access_bmap)
2759 {
2760 	return test_bit(NFS4_SHARE_ACCESS_WRITE, &access_bmap) ||
2761 		test_bit(NFS4_SHARE_ACCESS_BOTH, &access_bmap);
2762 }
2763 
2764 static
2765 __be32 nfs4_check_openmode(struct nfs4_stateid *stp, int flags)
2766 {
2767         __be32 status = nfserr_openmode;
2768 
2769 	if ((flags & WR_STATE) && (!access_permit_write(stp->st_access_bmap)))
2770                 goto out;
2771 	if ((flags & RD_STATE) && (!access_permit_read(stp->st_access_bmap)))
2772                 goto out;
2773 	status = nfs_ok;
2774 out:
2775 	return status;
2776 }
2777 
2778 static inline __be32
2779 check_special_stateids(svc_fh *current_fh, stateid_t *stateid, int flags)
2780 {
2781 	if (ONE_STATEID(stateid) && (flags & RD_STATE))
2782 		return nfs_ok;
2783 	else if (locks_in_grace()) {
2784 		/* Answer in remaining cases depends on existance of
2785 		 * conflicting state; so we must wait out the grace period. */
2786 		return nfserr_grace;
2787 	} else if (flags & WR_STATE)
2788 		return nfs4_share_conflict(current_fh,
2789 				NFS4_SHARE_DENY_WRITE);
2790 	else /* (flags & RD_STATE) && ZERO_STATEID(stateid) */
2791 		return nfs4_share_conflict(current_fh,
2792 				NFS4_SHARE_DENY_READ);
2793 }
2794 
2795 /*
2796  * Allow READ/WRITE during grace period on recovered state only for files
2797  * that are not able to provide mandatory locking.
2798  */
2799 static inline int
2800 grace_disallows_io(struct inode *inode)
2801 {
2802 	return locks_in_grace() && mandatory_lock(inode);
2803 }
2804 
2805 static int check_stateid_generation(stateid_t *in, stateid_t *ref, int flags)
2806 {
2807 	/*
2808 	 * When sessions are used the stateid generation number is ignored
2809 	 * when it is zero.
2810 	 */
2811 	if ((flags & HAS_SESSION) && in->si_generation == 0)
2812 		goto out;
2813 
2814 	/* If the client sends us a stateid from the future, it's buggy: */
2815 	if (in->si_generation > ref->si_generation)
2816 		return nfserr_bad_stateid;
2817 	/*
2818 	 * The following, however, can happen.  For example, if the
2819 	 * client sends an open and some IO at the same time, the open
2820 	 * may bump si_generation while the IO is still in flight.
2821 	 * Thanks to hard links and renames, the client never knows what
2822 	 * file an open will affect.  So it could avoid that situation
2823 	 * only by serializing all opens and IO from the same open
2824 	 * owner.  To recover from the old_stateid error, the client
2825 	 * will just have to retry the IO:
2826 	 */
2827 	if (in->si_generation < ref->si_generation)
2828 		return nfserr_old_stateid;
2829 out:
2830 	return nfs_ok;
2831 }
2832 
2833 static int is_delegation_stateid(stateid_t *stateid)
2834 {
2835 	return stateid->si_fileid == 0;
2836 }
2837 
2838 /*
2839 * Checks for stateid operations
2840 */
2841 __be32
2842 nfs4_preprocess_stateid_op(struct nfsd4_compound_state *cstate,
2843 			   stateid_t *stateid, int flags, struct file **filpp)
2844 {
2845 	struct nfs4_stateid *stp = NULL;
2846 	struct nfs4_delegation *dp = NULL;
2847 	struct svc_fh *current_fh = &cstate->current_fh;
2848 	struct inode *ino = current_fh->fh_dentry->d_inode;
2849 	__be32 status;
2850 
2851 	if (filpp)
2852 		*filpp = NULL;
2853 
2854 	if (grace_disallows_io(ino))
2855 		return nfserr_grace;
2856 
2857 	if (nfsd4_has_session(cstate))
2858 		flags |= HAS_SESSION;
2859 
2860 	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
2861 		return check_special_stateids(current_fh, stateid, flags);
2862 
2863 	status = nfserr_stale_stateid;
2864 	if (STALE_STATEID(stateid))
2865 		goto out;
2866 
2867 	status = nfserr_bad_stateid;
2868 	if (is_delegation_stateid(stateid)) {
2869 		dp = find_delegation_stateid(ino, stateid);
2870 		if (!dp)
2871 			goto out;
2872 		status = check_stateid_generation(stateid, &dp->dl_stateid,
2873 						  flags);
2874 		if (status)
2875 			goto out;
2876 		status = nfs4_check_delegmode(dp, flags);
2877 		if (status)
2878 			goto out;
2879 		renew_client(dp->dl_client);
2880 		if (filpp)
2881 			*filpp = dp->dl_vfs_file;
2882 	} else { /* open or lock stateid */
2883 		stp = find_stateid(stateid, flags);
2884 		if (!stp)
2885 			goto out;
2886 		if (nfs4_check_fh(current_fh, stp))
2887 			goto out;
2888 		if (!stp->st_stateowner->so_confirmed)
2889 			goto out;
2890 		status = check_stateid_generation(stateid, &stp->st_stateid,
2891 						  flags);
2892 		if (status)
2893 			goto out;
2894 		status = nfs4_check_openmode(stp, flags);
2895 		if (status)
2896 			goto out;
2897 		renew_client(stp->st_stateowner->so_client);
2898 		if (filpp)
2899 			*filpp = stp->st_vfs_file;
2900 	}
2901 	status = nfs_ok;
2902 out:
2903 	return status;
2904 }
2905 
2906 static inline int
2907 setlkflg (int type)
2908 {
2909 	return (type == NFS4_READW_LT || type == NFS4_READ_LT) ?
2910 		RD_STATE : WR_STATE;
2911 }
2912 
2913 /*
2914  * Checks for sequence id mutating operations.
2915  */
2916 static __be32
2917 nfs4_preprocess_seqid_op(struct nfsd4_compound_state *cstate, u32 seqid,
2918 			 stateid_t *stateid, int flags,
2919 			 struct nfs4_stateowner **sopp,
2920 			 struct nfs4_stateid **stpp, struct nfsd4_lock *lock)
2921 {
2922 	struct nfs4_stateid *stp;
2923 	struct nfs4_stateowner *sop;
2924 	struct svc_fh *current_fh = &cstate->current_fh;
2925 	__be32 status;
2926 
2927 	dprintk("NFSD: preprocess_seqid_op: seqid=%d "
2928 			"stateid = (%08x/%08x/%08x/%08x)\n", seqid,
2929 		stateid->si_boot, stateid->si_stateownerid, stateid->si_fileid,
2930 		stateid->si_generation);
2931 
2932 	*stpp = NULL;
2933 	*sopp = NULL;
2934 
2935 	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
2936 		dprintk("NFSD: preprocess_seqid_op: magic stateid!\n");
2937 		return nfserr_bad_stateid;
2938 	}
2939 
2940 	if (STALE_STATEID(stateid))
2941 		return nfserr_stale_stateid;
2942 
2943 	if (nfsd4_has_session(cstate))
2944 		flags |= HAS_SESSION;
2945 
2946 	/*
2947 	* We return BAD_STATEID if filehandle doesn't match stateid,
2948 	* the confirmed flag is incorrecly set, or the generation
2949 	* number is incorrect.
2950 	*/
2951 	stp = find_stateid(stateid, flags);
2952 	if (stp == NULL) {
2953 		/*
2954 		 * Also, we should make sure this isn't just the result of
2955 		 * a replayed close:
2956 		 */
2957 		sop = search_close_lru(stateid->si_stateownerid, flags);
2958 		if (sop == NULL)
2959 			return nfserr_bad_stateid;
2960 		*sopp = sop;
2961 		goto check_replay;
2962 	}
2963 
2964 	*stpp = stp;
2965 	*sopp = sop = stp->st_stateowner;
2966 
2967 	if (lock) {
2968 		clientid_t *lockclid = &lock->v.new.clientid;
2969 		struct nfs4_client *clp = sop->so_client;
2970 		int lkflg = 0;
2971 		__be32 status;
2972 
2973 		lkflg = setlkflg(lock->lk_type);
2974 
2975 		if (lock->lk_is_new) {
2976 			if (!sop->so_is_open_owner)
2977 				return nfserr_bad_stateid;
2978 			if (!(flags & HAS_SESSION) &&
2979 			    !same_clid(&clp->cl_clientid, lockclid))
2980 				return nfserr_bad_stateid;
2981 			/* stp is the open stateid */
2982 			status = nfs4_check_openmode(stp, lkflg);
2983 			if (status)
2984 				return status;
2985 		} else {
2986 			/* stp is the lock stateid */
2987 			status = nfs4_check_openmode(stp->st_openstp, lkflg);
2988 			if (status)
2989 				return status;
2990                }
2991 	}
2992 
2993 	if (nfs4_check_fh(current_fh, stp)) {
2994 		dprintk("NFSD: preprocess_seqid_op: fh-stateid mismatch!\n");
2995 		return nfserr_bad_stateid;
2996 	}
2997 
2998 	/*
2999 	*  We now validate the seqid and stateid generation numbers.
3000 	*  For the moment, we ignore the possibility of
3001 	*  generation number wraparound.
3002 	*/
3003 	if (!(flags & HAS_SESSION) && seqid != sop->so_seqid)
3004 		goto check_replay;
3005 
3006 	if (sop->so_confirmed && flags & CONFIRM) {
3007 		dprintk("NFSD: preprocess_seqid_op: expected"
3008 				" unconfirmed stateowner!\n");
3009 		return nfserr_bad_stateid;
3010 	}
3011 	if (!sop->so_confirmed && !(flags & CONFIRM)) {
3012 		dprintk("NFSD: preprocess_seqid_op: stateowner not"
3013 				" confirmed yet!\n");
3014 		return nfserr_bad_stateid;
3015 	}
3016 	status = check_stateid_generation(stateid, &stp->st_stateid, flags);
3017 	if (status)
3018 		return status;
3019 	renew_client(sop->so_client);
3020 	return nfs_ok;
3021 
3022 check_replay:
3023 	if (seqid == sop->so_seqid - 1) {
3024 		dprintk("NFSD: preprocess_seqid_op: retransmission?\n");
3025 		/* indicate replay to calling function */
3026 		return nfserr_replay_me;
3027 	}
3028 	dprintk("NFSD: preprocess_seqid_op: bad seqid (expected %d, got %d)\n",
3029 			sop->so_seqid, seqid);
3030 	*sopp = NULL;
3031 	return nfserr_bad_seqid;
3032 }
3033 
3034 __be32
3035 nfsd4_open_confirm(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
3036 		   struct nfsd4_open_confirm *oc)
3037 {
3038 	__be32 status;
3039 	struct nfs4_stateowner *sop;
3040 	struct nfs4_stateid *stp;
3041 
3042 	dprintk("NFSD: nfsd4_open_confirm on file %.*s\n",
3043 			(int)cstate->current_fh.fh_dentry->d_name.len,
3044 			cstate->current_fh.fh_dentry->d_name.name);
3045 
3046 	status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0);
3047 	if (status)
3048 		return status;
3049 
3050 	nfs4_lock_state();
3051 
3052 	if ((status = nfs4_preprocess_seqid_op(cstate,
3053 					oc->oc_seqid, &oc->oc_req_stateid,
3054 					CONFIRM | OPEN_STATE,
3055 					&oc->oc_stateowner, &stp, NULL)))
3056 		goto out;
3057 
3058 	sop = oc->oc_stateowner;
3059 	sop->so_confirmed = 1;
3060 	update_stateid(&stp->st_stateid);
3061 	memcpy(&oc->oc_resp_stateid, &stp->st_stateid, sizeof(stateid_t));
3062 	dprintk("NFSD: nfsd4_open_confirm: success, seqid=%d "
3063 		"stateid=(%08x/%08x/%08x/%08x)\n", oc->oc_seqid,
3064 		         stp->st_stateid.si_boot,
3065 		         stp->st_stateid.si_stateownerid,
3066 		         stp->st_stateid.si_fileid,
3067 		         stp->st_stateid.si_generation);
3068 
3069 	nfsd4_create_clid_dir(sop->so_client);
3070 out:
3071 	if (oc->oc_stateowner) {
3072 		nfs4_get_stateowner(oc->oc_stateowner);
3073 		cstate->replay_owner = oc->oc_stateowner;
3074 	}
3075 	nfs4_unlock_state();
3076 	return status;
3077 }
3078 
3079 
3080 /*
3081  * unset all bits in union bitmap (bmap) that
3082  * do not exist in share (from successful OPEN_DOWNGRADE)
3083  */
3084 static void
3085 reset_union_bmap_access(unsigned long access, unsigned long *bmap)
3086 {
3087 	int i;
3088 	for (i = 1; i < 4; i++) {
3089 		if ((i & access) != i)
3090 			__clear_bit(i, bmap);
3091 	}
3092 }
3093 
3094 static void
3095 reset_union_bmap_deny(unsigned long deny, unsigned long *bmap)
3096 {
3097 	int i;
3098 	for (i = 0; i < 4; i++) {
3099 		if ((i & deny) != i)
3100 			__clear_bit(i, bmap);
3101 	}
3102 }
3103 
3104 __be32
3105 nfsd4_open_downgrade(struct svc_rqst *rqstp,
3106 		     struct nfsd4_compound_state *cstate,
3107 		     struct nfsd4_open_downgrade *od)
3108 {
3109 	__be32 status;
3110 	struct nfs4_stateid *stp;
3111 	unsigned int share_access;
3112 
3113 	dprintk("NFSD: nfsd4_open_downgrade on file %.*s\n",
3114 			(int)cstate->current_fh.fh_dentry->d_name.len,
3115 			cstate->current_fh.fh_dentry->d_name.name);
3116 
3117 	if (!access_valid(od->od_share_access, cstate->minorversion)
3118 			|| !deny_valid(od->od_share_deny))
3119 		return nfserr_inval;
3120 
3121 	nfs4_lock_state();
3122 	if ((status = nfs4_preprocess_seqid_op(cstate,
3123 					od->od_seqid,
3124 					&od->od_stateid,
3125 					OPEN_STATE,
3126 					&od->od_stateowner, &stp, NULL)))
3127 		goto out;
3128 
3129 	status = nfserr_inval;
3130 	if (!test_bit(od->od_share_access, &stp->st_access_bmap)) {
3131 		dprintk("NFSD:access not a subset current bitmap: 0x%lx, input access=%08x\n",
3132 			stp->st_access_bmap, od->od_share_access);
3133 		goto out;
3134 	}
3135 	if (!test_bit(od->od_share_deny, &stp->st_deny_bmap)) {
3136 		dprintk("NFSD:deny not a subset current bitmap: 0x%lx, input deny=%08x\n",
3137 			stp->st_deny_bmap, od->od_share_deny);
3138 		goto out;
3139 	}
3140 	set_access(&share_access, stp->st_access_bmap);
3141 	nfs4_file_downgrade(stp->st_vfs_file,
3142 	                    share_access & ~od->od_share_access);
3143 
3144 	reset_union_bmap_access(od->od_share_access, &stp->st_access_bmap);
3145 	reset_union_bmap_deny(od->od_share_deny, &stp->st_deny_bmap);
3146 
3147 	update_stateid(&stp->st_stateid);
3148 	memcpy(&od->od_stateid, &stp->st_stateid, sizeof(stateid_t));
3149 	status = nfs_ok;
3150 out:
3151 	if (od->od_stateowner) {
3152 		nfs4_get_stateowner(od->od_stateowner);
3153 		cstate->replay_owner = od->od_stateowner;
3154 	}
3155 	nfs4_unlock_state();
3156 	return status;
3157 }
3158 
3159 /*
3160  * nfs4_unlock_state() called after encode
3161  */
3162 __be32
3163 nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
3164 	    struct nfsd4_close *close)
3165 {
3166 	__be32 status;
3167 	struct nfs4_stateid *stp;
3168 
3169 	dprintk("NFSD: nfsd4_close on file %.*s\n",
3170 			(int)cstate->current_fh.fh_dentry->d_name.len,
3171 			cstate->current_fh.fh_dentry->d_name.name);
3172 
3173 	nfs4_lock_state();
3174 	/* check close_lru for replay */
3175 	if ((status = nfs4_preprocess_seqid_op(cstate,
3176 					close->cl_seqid,
3177 					&close->cl_stateid,
3178 					OPEN_STATE | CLOSE_STATE,
3179 					&close->cl_stateowner, &stp, NULL)))
3180 		goto out;
3181 	status = nfs_ok;
3182 	update_stateid(&stp->st_stateid);
3183 	memcpy(&close->cl_stateid, &stp->st_stateid, sizeof(stateid_t));
3184 
3185 	/* release_stateid() calls nfsd_close() if needed */
3186 	release_open_stateid(stp);
3187 
3188 	/* place unused nfs4_stateowners on so_close_lru list to be
3189 	 * released by the laundromat service after the lease period
3190 	 * to enable us to handle CLOSE replay
3191 	 */
3192 	if (list_empty(&close->cl_stateowner->so_stateids))
3193 		move_to_close_lru(close->cl_stateowner);
3194 out:
3195 	if (close->cl_stateowner) {
3196 		nfs4_get_stateowner(close->cl_stateowner);
3197 		cstate->replay_owner = close->cl_stateowner;
3198 	}
3199 	nfs4_unlock_state();
3200 	return status;
3201 }
3202 
3203 __be32
3204 nfsd4_delegreturn(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
3205 		  struct nfsd4_delegreturn *dr)
3206 {
3207 	struct nfs4_delegation *dp;
3208 	stateid_t *stateid = &dr->dr_stateid;
3209 	struct inode *inode;
3210 	__be32 status;
3211 	int flags = 0;
3212 
3213 	if ((status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0)))
3214 		return status;
3215 	inode = cstate->current_fh.fh_dentry->d_inode;
3216 
3217 	if (nfsd4_has_session(cstate))
3218 		flags |= HAS_SESSION;
3219 	nfs4_lock_state();
3220 	status = nfserr_bad_stateid;
3221 	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
3222 		goto out;
3223 	status = nfserr_stale_stateid;
3224 	if (STALE_STATEID(stateid))
3225 		goto out;
3226 	status = nfserr_bad_stateid;
3227 	if (!is_delegation_stateid(stateid))
3228 		goto out;
3229 	dp = find_delegation_stateid(inode, stateid);
3230 	if (!dp)
3231 		goto out;
3232 	status = check_stateid_generation(stateid, &dp->dl_stateid, flags);
3233 	if (status)
3234 		goto out;
3235 	renew_client(dp->dl_client);
3236 
3237 	unhash_delegation(dp);
3238 out:
3239 	nfs4_unlock_state();
3240 
3241 	return status;
3242 }
3243 
3244 
3245 /*
3246  * Lock owner state (byte-range locks)
3247  */
3248 #define LOFF_OVERFLOW(start, len)      ((u64)(len) > ~(u64)(start))
3249 #define LOCK_HASH_BITS              8
3250 #define LOCK_HASH_SIZE             (1 << LOCK_HASH_BITS)
3251 #define LOCK_HASH_MASK             (LOCK_HASH_SIZE - 1)
3252 
3253 static inline u64
3254 end_offset(u64 start, u64 len)
3255 {
3256 	u64 end;
3257 
3258 	end = start + len;
3259 	return end >= start ? end: NFS4_MAX_UINT64;
3260 }
3261 
3262 /* last octet in a range */
3263 static inline u64
3264 last_byte_offset(u64 start, u64 len)
3265 {
3266 	u64 end;
3267 
3268 	BUG_ON(!len);
3269 	end = start + len;
3270 	return end > start ? end - 1: NFS4_MAX_UINT64;
3271 }
3272 
3273 #define lockownerid_hashval(id) \
3274         ((id) & LOCK_HASH_MASK)
3275 
3276 static inline unsigned int
3277 lock_ownerstr_hashval(struct inode *inode, u32 cl_id,
3278 		struct xdr_netobj *ownername)
3279 {
3280 	return (file_hashval(inode) + cl_id
3281 			+ opaque_hashval(ownername->data, ownername->len))
3282 		& LOCK_HASH_MASK;
3283 }
3284 
3285 static struct list_head lock_ownerid_hashtbl[LOCK_HASH_SIZE];
3286 static struct list_head	lock_ownerstr_hashtbl[LOCK_HASH_SIZE];
3287 static struct list_head lockstateid_hashtbl[STATEID_HASH_SIZE];
3288 
3289 static struct nfs4_stateid *
3290 find_stateid(stateid_t *stid, int flags)
3291 {
3292 	struct nfs4_stateid *local;
3293 	u32 st_id = stid->si_stateownerid;
3294 	u32 f_id = stid->si_fileid;
3295 	unsigned int hashval;
3296 
3297 	dprintk("NFSD: find_stateid flags 0x%x\n",flags);
3298 	if (flags & (LOCK_STATE | RD_STATE | WR_STATE)) {
3299 		hashval = stateid_hashval(st_id, f_id);
3300 		list_for_each_entry(local, &lockstateid_hashtbl[hashval], st_hash) {
3301 			if ((local->st_stateid.si_stateownerid == st_id) &&
3302 			    (local->st_stateid.si_fileid == f_id))
3303 				return local;
3304 		}
3305 	}
3306 
3307 	if (flags & (OPEN_STATE | RD_STATE | WR_STATE)) {
3308 		hashval = stateid_hashval(st_id, f_id);
3309 		list_for_each_entry(local, &stateid_hashtbl[hashval], st_hash) {
3310 			if ((local->st_stateid.si_stateownerid == st_id) &&
3311 			    (local->st_stateid.si_fileid == f_id))
3312 				return local;
3313 		}
3314 	}
3315 	return NULL;
3316 }
3317 
3318 static struct nfs4_delegation *
3319 find_delegation_stateid(struct inode *ino, stateid_t *stid)
3320 {
3321 	struct nfs4_file *fp;
3322 	struct nfs4_delegation *dl;
3323 
3324 	dprintk("NFSD:find_delegation_stateid stateid=(%08x/%08x/%08x/%08x)\n",
3325                     stid->si_boot, stid->si_stateownerid,
3326                     stid->si_fileid, stid->si_generation);
3327 
3328 	fp = find_file(ino);
3329 	if (!fp)
3330 		return NULL;
3331 	dl = find_delegation_file(fp, stid);
3332 	put_nfs4_file(fp);
3333 	return dl;
3334 }
3335 
3336 /*
3337  * TODO: Linux file offsets are _signed_ 64-bit quantities, which means that
3338  * we can't properly handle lock requests that go beyond the (2^63 - 1)-th
3339  * byte, because of sign extension problems.  Since NFSv4 calls for 64-bit
3340  * locking, this prevents us from being completely protocol-compliant.  The
3341  * real solution to this problem is to start using unsigned file offsets in
3342  * the VFS, but this is a very deep change!
3343  */
3344 static inline void
3345 nfs4_transform_lock_offset(struct file_lock *lock)
3346 {
3347 	if (lock->fl_start < 0)
3348 		lock->fl_start = OFFSET_MAX;
3349 	if (lock->fl_end < 0)
3350 		lock->fl_end = OFFSET_MAX;
3351 }
3352 
3353 /* Hack!: For now, we're defining this just so we can use a pointer to it
3354  * as a unique cookie to identify our (NFSv4's) posix locks. */
3355 static struct lock_manager_operations nfsd_posix_mng_ops  = {
3356 };
3357 
3358 static inline void
3359 nfs4_set_lock_denied(struct file_lock *fl, struct nfsd4_lock_denied *deny)
3360 {
3361 	struct nfs4_stateowner *sop;
3362 	unsigned int hval;
3363 
3364 	if (fl->fl_lmops == &nfsd_posix_mng_ops) {
3365 		sop = (struct nfs4_stateowner *) fl->fl_owner;
3366 		hval = lockownerid_hashval(sop->so_id);
3367 		kref_get(&sop->so_ref);
3368 		deny->ld_sop = sop;
3369 		deny->ld_clientid = sop->so_client->cl_clientid;
3370 	} else {
3371 		deny->ld_sop = NULL;
3372 		deny->ld_clientid.cl_boot = 0;
3373 		deny->ld_clientid.cl_id = 0;
3374 	}
3375 	deny->ld_start = fl->fl_start;
3376 	deny->ld_length = NFS4_MAX_UINT64;
3377 	if (fl->fl_end != NFS4_MAX_UINT64)
3378 		deny->ld_length = fl->fl_end - fl->fl_start + 1;
3379 	deny->ld_type = NFS4_READ_LT;
3380 	if (fl->fl_type != F_RDLCK)
3381 		deny->ld_type = NFS4_WRITE_LT;
3382 }
3383 
3384 static struct nfs4_stateowner *
3385 find_lockstateowner_str(struct inode *inode, clientid_t *clid,
3386 		struct xdr_netobj *owner)
3387 {
3388 	unsigned int hashval = lock_ownerstr_hashval(inode, clid->cl_id, owner);
3389 	struct nfs4_stateowner *op;
3390 
3391 	list_for_each_entry(op, &lock_ownerstr_hashtbl[hashval], so_strhash) {
3392 		if (same_owner_str(op, owner, clid))
3393 			return op;
3394 	}
3395 	return NULL;
3396 }
3397 
3398 /*
3399  * Alloc a lock owner structure.
3400  * Called in nfsd4_lock - therefore, OPEN and OPEN_CONFIRM (if needed) has
3401  * occured.
3402  *
3403  * strhashval = lock_ownerstr_hashval
3404  */
3405 
3406 static struct nfs4_stateowner *
3407 alloc_init_lock_stateowner(unsigned int strhashval, struct nfs4_client *clp, struct nfs4_stateid *open_stp, struct nfsd4_lock *lock) {
3408 	struct nfs4_stateowner *sop;
3409 	struct nfs4_replay *rp;
3410 	unsigned int idhashval;
3411 
3412 	if (!(sop = alloc_stateowner(&lock->lk_new_owner)))
3413 		return NULL;
3414 	idhashval = lockownerid_hashval(current_ownerid);
3415 	INIT_LIST_HEAD(&sop->so_idhash);
3416 	INIT_LIST_HEAD(&sop->so_strhash);
3417 	INIT_LIST_HEAD(&sop->so_perclient);
3418 	INIT_LIST_HEAD(&sop->so_stateids);
3419 	INIT_LIST_HEAD(&sop->so_perstateid);
3420 	INIT_LIST_HEAD(&sop->so_close_lru); /* not used */
3421 	sop->so_time = 0;
3422 	list_add(&sop->so_idhash, &lock_ownerid_hashtbl[idhashval]);
3423 	list_add(&sop->so_strhash, &lock_ownerstr_hashtbl[strhashval]);
3424 	list_add(&sop->so_perstateid, &open_stp->st_lockowners);
3425 	sop->so_is_open_owner = 0;
3426 	sop->so_id = current_ownerid++;
3427 	sop->so_client = clp;
3428 	/* It is the openowner seqid that will be incremented in encode in the
3429 	 * case of new lockowners; so increment the lock seqid manually: */
3430 	sop->so_seqid = lock->lk_new_lock_seqid + 1;
3431 	sop->so_confirmed = 1;
3432 	rp = &sop->so_replay;
3433 	rp->rp_status = nfserr_serverfault;
3434 	rp->rp_buflen = 0;
3435 	rp->rp_buf = rp->rp_ibuf;
3436 	return sop;
3437 }
3438 
3439 static struct nfs4_stateid *
3440 alloc_init_lock_stateid(struct nfs4_stateowner *sop, struct nfs4_file *fp, struct nfs4_stateid *open_stp)
3441 {
3442 	struct nfs4_stateid *stp;
3443 	unsigned int hashval = stateid_hashval(sop->so_id, fp->fi_id);
3444 
3445 	stp = nfs4_alloc_stateid();
3446 	if (stp == NULL)
3447 		goto out;
3448 	INIT_LIST_HEAD(&stp->st_hash);
3449 	INIT_LIST_HEAD(&stp->st_perfile);
3450 	INIT_LIST_HEAD(&stp->st_perstateowner);
3451 	INIT_LIST_HEAD(&stp->st_lockowners); /* not used */
3452 	list_add(&stp->st_hash, &lockstateid_hashtbl[hashval]);
3453 	list_add(&stp->st_perfile, &fp->fi_stateids);
3454 	list_add(&stp->st_perstateowner, &sop->so_stateids);
3455 	stp->st_stateowner = sop;
3456 	get_nfs4_file(fp);
3457 	stp->st_file = fp;
3458 	stp->st_stateid.si_boot = boot_time;
3459 	stp->st_stateid.si_stateownerid = sop->so_id;
3460 	stp->st_stateid.si_fileid = fp->fi_id;
3461 	stp->st_stateid.si_generation = 0;
3462 	stp->st_vfs_file = open_stp->st_vfs_file; /* FIXME refcount?? */
3463 	stp->st_access_bmap = open_stp->st_access_bmap;
3464 	stp->st_deny_bmap = open_stp->st_deny_bmap;
3465 	stp->st_openstp = open_stp;
3466 
3467 out:
3468 	return stp;
3469 }
3470 
3471 static int
3472 check_lock_length(u64 offset, u64 length)
3473 {
3474 	return ((length == 0)  || ((length != NFS4_MAX_UINT64) &&
3475 	     LOFF_OVERFLOW(offset, length)));
3476 }
3477 
3478 /*
3479  *  LOCK operation
3480  */
3481 __be32
3482 nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
3483 	   struct nfsd4_lock *lock)
3484 {
3485 	struct nfs4_stateowner *open_sop = NULL;
3486 	struct nfs4_stateowner *lock_sop = NULL;
3487 	struct nfs4_stateid *lock_stp;
3488 	struct file *filp;
3489 	struct file_lock file_lock;
3490 	struct file_lock conflock;
3491 	__be32 status = 0;
3492 	unsigned int strhashval;
3493 	unsigned int cmd;
3494 	int err;
3495 
3496 	dprintk("NFSD: nfsd4_lock: start=%Ld length=%Ld\n",
3497 		(long long) lock->lk_offset,
3498 		(long long) lock->lk_length);
3499 
3500 	if (check_lock_length(lock->lk_offset, lock->lk_length))
3501 		 return nfserr_inval;
3502 
3503 	if ((status = fh_verify(rqstp, &cstate->current_fh,
3504 				S_IFREG, NFSD_MAY_LOCK))) {
3505 		dprintk("NFSD: nfsd4_lock: permission denied!\n");
3506 		return status;
3507 	}
3508 
3509 	nfs4_lock_state();
3510 
3511 	if (lock->lk_is_new) {
3512 		/*
3513 		 * Client indicates that this is a new lockowner.
3514 		 * Use open owner and open stateid to create lock owner and
3515 		 * lock stateid.
3516 		 */
3517 		struct nfs4_stateid *open_stp = NULL;
3518 		struct nfs4_file *fp;
3519 
3520 		status = nfserr_stale_clientid;
3521 		if (!nfsd4_has_session(cstate) &&
3522 		    STALE_CLIENTID(&lock->lk_new_clientid))
3523 			goto out;
3524 
3525 		/* validate and update open stateid and open seqid */
3526 		status = nfs4_preprocess_seqid_op(cstate,
3527 				        lock->lk_new_open_seqid,
3528 		                        &lock->lk_new_open_stateid,
3529 					OPEN_STATE,
3530 		                        &lock->lk_replay_owner, &open_stp,
3531 					lock);
3532 		if (status)
3533 			goto out;
3534 		open_sop = lock->lk_replay_owner;
3535 		/* create lockowner and lock stateid */
3536 		fp = open_stp->st_file;
3537 		strhashval = lock_ownerstr_hashval(fp->fi_inode,
3538 				open_sop->so_client->cl_clientid.cl_id,
3539 				&lock->v.new.owner);
3540 		/* XXX: Do we need to check for duplicate stateowners on
3541 		 * the same file, or should they just be allowed (and
3542 		 * create new stateids)? */
3543 		status = nfserr_resource;
3544 		lock_sop = alloc_init_lock_stateowner(strhashval,
3545 				open_sop->so_client, open_stp, lock);
3546 		if (lock_sop == NULL)
3547 			goto out;
3548 		lock_stp = alloc_init_lock_stateid(lock_sop, fp, open_stp);
3549 		if (lock_stp == NULL)
3550 			goto out;
3551 	} else {
3552 		/* lock (lock owner + lock stateid) already exists */
3553 		status = nfs4_preprocess_seqid_op(cstate,
3554 				       lock->lk_old_lock_seqid,
3555 				       &lock->lk_old_lock_stateid,
3556 				       LOCK_STATE,
3557 				       &lock->lk_replay_owner, &lock_stp, lock);
3558 		if (status)
3559 			goto out;
3560 		lock_sop = lock->lk_replay_owner;
3561 	}
3562 	/* lock->lk_replay_owner and lock_stp have been created or found */
3563 	filp = lock_stp->st_vfs_file;
3564 
3565 	status = nfserr_grace;
3566 	if (locks_in_grace() && !lock->lk_reclaim)
3567 		goto out;
3568 	status = nfserr_no_grace;
3569 	if (!locks_in_grace() && lock->lk_reclaim)
3570 		goto out;
3571 
3572 	locks_init_lock(&file_lock);
3573 	switch (lock->lk_type) {
3574 		case NFS4_READ_LT:
3575 		case NFS4_READW_LT:
3576 			file_lock.fl_type = F_RDLCK;
3577 			cmd = F_SETLK;
3578 		break;
3579 		case NFS4_WRITE_LT:
3580 		case NFS4_WRITEW_LT:
3581 			file_lock.fl_type = F_WRLCK;
3582 			cmd = F_SETLK;
3583 		break;
3584 		default:
3585 			status = nfserr_inval;
3586 		goto out;
3587 	}
3588 	file_lock.fl_owner = (fl_owner_t)lock_sop;
3589 	file_lock.fl_pid = current->tgid;
3590 	file_lock.fl_file = filp;
3591 	file_lock.fl_flags = FL_POSIX;
3592 	file_lock.fl_lmops = &nfsd_posix_mng_ops;
3593 
3594 	file_lock.fl_start = lock->lk_offset;
3595 	file_lock.fl_end = last_byte_offset(lock->lk_offset, lock->lk_length);
3596 	nfs4_transform_lock_offset(&file_lock);
3597 
3598 	/*
3599 	* Try to lock the file in the VFS.
3600 	* Note: locks.c uses the BKL to protect the inode's lock list.
3601 	*/
3602 
3603 	err = vfs_lock_file(filp, cmd, &file_lock, &conflock);
3604 	switch (-err) {
3605 	case 0: /* success! */
3606 		update_stateid(&lock_stp->st_stateid);
3607 		memcpy(&lock->lk_resp_stateid, &lock_stp->st_stateid,
3608 				sizeof(stateid_t));
3609 		status = 0;
3610 		break;
3611 	case (EAGAIN):		/* conflock holds conflicting lock */
3612 		status = nfserr_denied;
3613 		dprintk("NFSD: nfsd4_lock: conflicting lock found!\n");
3614 		nfs4_set_lock_denied(&conflock, &lock->lk_denied);
3615 		break;
3616 	case (EDEADLK):
3617 		status = nfserr_deadlock;
3618 		break;
3619 	default:
3620 		dprintk("NFSD: nfsd4_lock: vfs_lock_file() failed! status %d\n",err);
3621 		status = nfserr_resource;
3622 		break;
3623 	}
3624 out:
3625 	if (status && lock->lk_is_new && lock_sop)
3626 		release_lockowner(lock_sop);
3627 	if (lock->lk_replay_owner) {
3628 		nfs4_get_stateowner(lock->lk_replay_owner);
3629 		cstate->replay_owner = lock->lk_replay_owner;
3630 	}
3631 	nfs4_unlock_state();
3632 	return status;
3633 }
3634 
3635 /*
3636  * The NFSv4 spec allows a client to do a LOCKT without holding an OPEN,
3637  * so we do a temporary open here just to get an open file to pass to
3638  * vfs_test_lock.  (Arguably perhaps test_lock should be done with an
3639  * inode operation.)
3640  */
3641 static int nfsd_test_lock(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file_lock *lock)
3642 {
3643 	struct file *file;
3644 	int err;
3645 
3646 	err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file);
3647 	if (err)
3648 		return err;
3649 	err = vfs_test_lock(file, lock);
3650 	nfsd_close(file);
3651 	return err;
3652 }
3653 
3654 /*
3655  * LOCKT operation
3656  */
3657 __be32
3658 nfsd4_lockt(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
3659 	    struct nfsd4_lockt *lockt)
3660 {
3661 	struct inode *inode;
3662 	struct file_lock file_lock;
3663 	int error;
3664 	__be32 status;
3665 
3666 	if (locks_in_grace())
3667 		return nfserr_grace;
3668 
3669 	if (check_lock_length(lockt->lt_offset, lockt->lt_length))
3670 		 return nfserr_inval;
3671 
3672 	lockt->lt_stateowner = NULL;
3673 	nfs4_lock_state();
3674 
3675 	status = nfserr_stale_clientid;
3676 	if (!nfsd4_has_session(cstate) && STALE_CLIENTID(&lockt->lt_clientid))
3677 		goto out;
3678 
3679 	if ((status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0))) {
3680 		dprintk("NFSD: nfsd4_lockt: fh_verify() failed!\n");
3681 		if (status == nfserr_symlink)
3682 			status = nfserr_inval;
3683 		goto out;
3684 	}
3685 
3686 	inode = cstate->current_fh.fh_dentry->d_inode;
3687 	locks_init_lock(&file_lock);
3688 	switch (lockt->lt_type) {
3689 		case NFS4_READ_LT:
3690 		case NFS4_READW_LT:
3691 			file_lock.fl_type = F_RDLCK;
3692 		break;
3693 		case NFS4_WRITE_LT:
3694 		case NFS4_WRITEW_LT:
3695 			file_lock.fl_type = F_WRLCK;
3696 		break;
3697 		default:
3698 			dprintk("NFSD: nfs4_lockt: bad lock type!\n");
3699 			status = nfserr_inval;
3700 		goto out;
3701 	}
3702 
3703 	lockt->lt_stateowner = find_lockstateowner_str(inode,
3704 			&lockt->lt_clientid, &lockt->lt_owner);
3705 	if (lockt->lt_stateowner)
3706 		file_lock.fl_owner = (fl_owner_t)lockt->lt_stateowner;
3707 	file_lock.fl_pid = current->tgid;
3708 	file_lock.fl_flags = FL_POSIX;
3709 
3710 	file_lock.fl_start = lockt->lt_offset;
3711 	file_lock.fl_end = last_byte_offset(lockt->lt_offset, lockt->lt_length);
3712 
3713 	nfs4_transform_lock_offset(&file_lock);
3714 
3715 	status = nfs_ok;
3716 	error = nfsd_test_lock(rqstp, &cstate->current_fh, &file_lock);
3717 	if (error) {
3718 		status = nfserrno(error);
3719 		goto out;
3720 	}
3721 	if (file_lock.fl_type != F_UNLCK) {
3722 		status = nfserr_denied;
3723 		nfs4_set_lock_denied(&file_lock, &lockt->lt_denied);
3724 	}
3725 out:
3726 	nfs4_unlock_state();
3727 	return status;
3728 }
3729 
3730 __be32
3731 nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
3732 	    struct nfsd4_locku *locku)
3733 {
3734 	struct nfs4_stateid *stp;
3735 	struct file *filp = NULL;
3736 	struct file_lock file_lock;
3737 	__be32 status;
3738 	int err;
3739 
3740 	dprintk("NFSD: nfsd4_locku: start=%Ld length=%Ld\n",
3741 		(long long) locku->lu_offset,
3742 		(long long) locku->lu_length);
3743 
3744 	if (check_lock_length(locku->lu_offset, locku->lu_length))
3745 		 return nfserr_inval;
3746 
3747 	nfs4_lock_state();
3748 
3749 	if ((status = nfs4_preprocess_seqid_op(cstate,
3750 					locku->lu_seqid,
3751 					&locku->lu_stateid,
3752 					LOCK_STATE,
3753 					&locku->lu_stateowner, &stp, NULL)))
3754 		goto out;
3755 
3756 	filp = stp->st_vfs_file;
3757 	BUG_ON(!filp);
3758 	locks_init_lock(&file_lock);
3759 	file_lock.fl_type = F_UNLCK;
3760 	file_lock.fl_owner = (fl_owner_t) locku->lu_stateowner;
3761 	file_lock.fl_pid = current->tgid;
3762 	file_lock.fl_file = filp;
3763 	file_lock.fl_flags = FL_POSIX;
3764 	file_lock.fl_lmops = &nfsd_posix_mng_ops;
3765 	file_lock.fl_start = locku->lu_offset;
3766 
3767 	file_lock.fl_end = last_byte_offset(locku->lu_offset, locku->lu_length);
3768 	nfs4_transform_lock_offset(&file_lock);
3769 
3770 	/*
3771 	*  Try to unlock the file in the VFS.
3772 	*/
3773 	err = vfs_lock_file(filp, F_SETLK, &file_lock, NULL);
3774 	if (err) {
3775 		dprintk("NFSD: nfs4_locku: vfs_lock_file failed!\n");
3776 		goto out_nfserr;
3777 	}
3778 	/*
3779 	* OK, unlock succeeded; the only thing left to do is update the stateid.
3780 	*/
3781 	update_stateid(&stp->st_stateid);
3782 	memcpy(&locku->lu_stateid, &stp->st_stateid, sizeof(stateid_t));
3783 
3784 out:
3785 	if (locku->lu_stateowner) {
3786 		nfs4_get_stateowner(locku->lu_stateowner);
3787 		cstate->replay_owner = locku->lu_stateowner;
3788 	}
3789 	nfs4_unlock_state();
3790 	return status;
3791 
3792 out_nfserr:
3793 	status = nfserrno(err);
3794 	goto out;
3795 }
3796 
3797 /*
3798  * returns
3799  * 	1: locks held by lockowner
3800  * 	0: no locks held by lockowner
3801  */
3802 static int
3803 check_for_locks(struct file *filp, struct nfs4_stateowner *lowner)
3804 {
3805 	struct file_lock **flpp;
3806 	struct inode *inode = filp->f_path.dentry->d_inode;
3807 	int status = 0;
3808 
3809 	lock_kernel();
3810 	for (flpp = &inode->i_flock; *flpp != NULL; flpp = &(*flpp)->fl_next) {
3811 		if ((*flpp)->fl_owner == (fl_owner_t)lowner) {
3812 			status = 1;
3813 			goto out;
3814 		}
3815 	}
3816 out:
3817 	unlock_kernel();
3818 	return status;
3819 }
3820 
3821 __be32
3822 nfsd4_release_lockowner(struct svc_rqst *rqstp,
3823 			struct nfsd4_compound_state *cstate,
3824 			struct nfsd4_release_lockowner *rlockowner)
3825 {
3826 	clientid_t *clid = &rlockowner->rl_clientid;
3827 	struct nfs4_stateowner *sop;
3828 	struct nfs4_stateid *stp;
3829 	struct xdr_netobj *owner = &rlockowner->rl_owner;
3830 	struct list_head matches;
3831 	int i;
3832 	__be32 status;
3833 
3834 	dprintk("nfsd4_release_lockowner clientid: (%08x/%08x):\n",
3835 		clid->cl_boot, clid->cl_id);
3836 
3837 	/* XXX check for lease expiration */
3838 
3839 	status = nfserr_stale_clientid;
3840 	if (STALE_CLIENTID(clid))
3841 		return status;
3842 
3843 	nfs4_lock_state();
3844 
3845 	status = nfserr_locks_held;
3846 	/* XXX: we're doing a linear search through all the lockowners.
3847 	 * Yipes!  For now we'll just hope clients aren't really using
3848 	 * release_lockowner much, but eventually we have to fix these
3849 	 * data structures. */
3850 	INIT_LIST_HEAD(&matches);
3851 	for (i = 0; i < LOCK_HASH_SIZE; i++) {
3852 		list_for_each_entry(sop, &lock_ownerid_hashtbl[i], so_idhash) {
3853 			if (!same_owner_str(sop, owner, clid))
3854 				continue;
3855 			list_for_each_entry(stp, &sop->so_stateids,
3856 					st_perstateowner) {
3857 				if (check_for_locks(stp->st_vfs_file, sop))
3858 					goto out;
3859 				/* Note: so_perclient unused for lockowners,
3860 				 * so it's OK to fool with here. */
3861 				list_add(&sop->so_perclient, &matches);
3862 			}
3863 		}
3864 	}
3865 	/* Clients probably won't expect us to return with some (but not all)
3866 	 * of the lockowner state released; so don't release any until all
3867 	 * have been checked. */
3868 	status = nfs_ok;
3869 	while (!list_empty(&matches)) {
3870 		sop = list_entry(matches.next, struct nfs4_stateowner,
3871 								so_perclient);
3872 		/* unhash_stateowner deletes so_perclient only
3873 		 * for openowners. */
3874 		list_del(&sop->so_perclient);
3875 		release_lockowner(sop);
3876 	}
3877 out:
3878 	nfs4_unlock_state();
3879 	return status;
3880 }
3881 
3882 static inline struct nfs4_client_reclaim *
3883 alloc_reclaim(void)
3884 {
3885 	return kmalloc(sizeof(struct nfs4_client_reclaim), GFP_KERNEL);
3886 }
3887 
3888 int
3889 nfs4_has_reclaimed_state(const char *name, bool use_exchange_id)
3890 {
3891 	unsigned int strhashval = clientstr_hashval(name);
3892 	struct nfs4_client *clp;
3893 
3894 	clp = find_confirmed_client_by_str(name, strhashval, use_exchange_id);
3895 	return clp ? 1 : 0;
3896 }
3897 
3898 /*
3899  * failure => all reset bets are off, nfserr_no_grace...
3900  */
3901 int
3902 nfs4_client_to_reclaim(const char *name)
3903 {
3904 	unsigned int strhashval;
3905 	struct nfs4_client_reclaim *crp = NULL;
3906 
3907 	dprintk("NFSD nfs4_client_to_reclaim NAME: %.*s\n", HEXDIR_LEN, name);
3908 	crp = alloc_reclaim();
3909 	if (!crp)
3910 		return 0;
3911 	strhashval = clientstr_hashval(name);
3912 	INIT_LIST_HEAD(&crp->cr_strhash);
3913 	list_add(&crp->cr_strhash, &reclaim_str_hashtbl[strhashval]);
3914 	memcpy(crp->cr_recdir, name, HEXDIR_LEN);
3915 	reclaim_str_hashtbl_size++;
3916 	return 1;
3917 }
3918 
3919 static void
3920 nfs4_release_reclaim(void)
3921 {
3922 	struct nfs4_client_reclaim *crp = NULL;
3923 	int i;
3924 
3925 	for (i = 0; i < CLIENT_HASH_SIZE; i++) {
3926 		while (!list_empty(&reclaim_str_hashtbl[i])) {
3927 			crp = list_entry(reclaim_str_hashtbl[i].next,
3928 			                struct nfs4_client_reclaim, cr_strhash);
3929 			list_del(&crp->cr_strhash);
3930 			kfree(crp);
3931 			reclaim_str_hashtbl_size--;
3932 		}
3933 	}
3934 	BUG_ON(reclaim_str_hashtbl_size);
3935 }
3936 
3937 /*
3938  * called from OPEN, CLAIM_PREVIOUS with a new clientid. */
3939 static struct nfs4_client_reclaim *
3940 nfs4_find_reclaim_client(clientid_t *clid)
3941 {
3942 	unsigned int strhashval;
3943 	struct nfs4_client *clp;
3944 	struct nfs4_client_reclaim *crp = NULL;
3945 
3946 
3947 	/* find clientid in conf_id_hashtbl */
3948 	clp = find_confirmed_client(clid);
3949 	if (clp == NULL)
3950 		return NULL;
3951 
3952 	dprintk("NFSD: nfs4_find_reclaim_client for %.*s with recdir %s\n",
3953 		            clp->cl_name.len, clp->cl_name.data,
3954 			    clp->cl_recdir);
3955 
3956 	/* find clp->cl_name in reclaim_str_hashtbl */
3957 	strhashval = clientstr_hashval(clp->cl_recdir);
3958 	list_for_each_entry(crp, &reclaim_str_hashtbl[strhashval], cr_strhash) {
3959 		if (same_name(crp->cr_recdir, clp->cl_recdir)) {
3960 			return crp;
3961 		}
3962 	}
3963 	return NULL;
3964 }
3965 
3966 /*
3967 * Called from OPEN. Look for clientid in reclaim list.
3968 */
3969 __be32
3970 nfs4_check_open_reclaim(clientid_t *clid)
3971 {
3972 	return nfs4_find_reclaim_client(clid) ? nfs_ok : nfserr_reclaim_bad;
3973 }
3974 
3975 /* initialization to perform at module load time: */
3976 
3977 int
3978 nfs4_state_init(void)
3979 {
3980 	int i, status;
3981 
3982 	status = nfsd4_init_slabs();
3983 	if (status)
3984 		return status;
3985 	for (i = 0; i < CLIENT_HASH_SIZE; i++) {
3986 		INIT_LIST_HEAD(&conf_id_hashtbl[i]);
3987 		INIT_LIST_HEAD(&conf_str_hashtbl[i]);
3988 		INIT_LIST_HEAD(&unconf_str_hashtbl[i]);
3989 		INIT_LIST_HEAD(&unconf_id_hashtbl[i]);
3990 	}
3991 	for (i = 0; i < SESSION_HASH_SIZE; i++)
3992 		INIT_LIST_HEAD(&sessionid_hashtbl[i]);
3993 	for (i = 0; i < FILE_HASH_SIZE; i++) {
3994 		INIT_LIST_HEAD(&file_hashtbl[i]);
3995 	}
3996 	for (i = 0; i < OWNER_HASH_SIZE; i++) {
3997 		INIT_LIST_HEAD(&ownerstr_hashtbl[i]);
3998 		INIT_LIST_HEAD(&ownerid_hashtbl[i]);
3999 	}
4000 	for (i = 0; i < STATEID_HASH_SIZE; i++) {
4001 		INIT_LIST_HEAD(&stateid_hashtbl[i]);
4002 		INIT_LIST_HEAD(&lockstateid_hashtbl[i]);
4003 	}
4004 	for (i = 0; i < LOCK_HASH_SIZE; i++) {
4005 		INIT_LIST_HEAD(&lock_ownerid_hashtbl[i]);
4006 		INIT_LIST_HEAD(&lock_ownerstr_hashtbl[i]);
4007 	}
4008 	memset(&onestateid, ~0, sizeof(stateid_t));
4009 	INIT_LIST_HEAD(&close_lru);
4010 	INIT_LIST_HEAD(&client_lru);
4011 	INIT_LIST_HEAD(&del_recall_lru);
4012 	for (i = 0; i < CLIENT_HASH_SIZE; i++)
4013 		INIT_LIST_HEAD(&reclaim_str_hashtbl[i]);
4014 	reclaim_str_hashtbl_size = 0;
4015 	return 0;
4016 }
4017 
4018 static void
4019 nfsd4_load_reboot_recovery_data(void)
4020 {
4021 	int status;
4022 
4023 	nfs4_lock_state();
4024 	nfsd4_init_recdir(user_recovery_dirname);
4025 	status = nfsd4_recdir_load();
4026 	nfs4_unlock_state();
4027 	if (status)
4028 		printk("NFSD: Failure reading reboot recovery data\n");
4029 }
4030 
4031 unsigned long
4032 get_nfs4_grace_period(void)
4033 {
4034 	return max(user_lease_time, lease_time) * HZ;
4035 }
4036 
4037 /*
4038  * Since the lifetime of a delegation isn't limited to that of an open, a
4039  * client may quite reasonably hang on to a delegation as long as it has
4040  * the inode cached.  This becomes an obvious problem the first time a
4041  * client's inode cache approaches the size of the server's total memory.
4042  *
4043  * For now we avoid this problem by imposing a hard limit on the number
4044  * of delegations, which varies according to the server's memory size.
4045  */
4046 static void
4047 set_max_delegations(void)
4048 {
4049 	/*
4050 	 * Allow at most 4 delegations per megabyte of RAM.  Quick
4051 	 * estimates suggest that in the worst case (where every delegation
4052 	 * is for a different inode), a delegation could take about 1.5K,
4053 	 * giving a worst case usage of about 6% of memory.
4054 	 */
4055 	max_delegations = nr_free_buffer_pages() >> (20 - 2 - PAGE_SHIFT);
4056 }
4057 
4058 /* initialization to perform when the nfsd service is started: */
4059 
4060 static void
4061 __nfs4_state_start(void)
4062 {
4063 	unsigned long grace_time;
4064 
4065 	boot_time = get_seconds();
4066 	grace_time = get_nfs4_grace_period();
4067 	lease_time = user_lease_time;
4068 	locks_start_grace(&nfsd4_manager);
4069 	printk(KERN_INFO "NFSD: starting %ld-second grace period\n",
4070 	       grace_time/HZ);
4071 	laundry_wq = create_singlethread_workqueue("nfsd4");
4072 	queue_delayed_work(laundry_wq, &laundromat_work, grace_time);
4073 	set_max_delegations();
4074 }
4075 
4076 void
4077 nfs4_state_start(void)
4078 {
4079 	if (nfs4_init)
4080 		return;
4081 	nfsd4_load_reboot_recovery_data();
4082 	__nfs4_state_start();
4083 	nfs4_init = 1;
4084 	return;
4085 }
4086 
4087 time_t
4088 nfs4_lease_time(void)
4089 {
4090 	return lease_time;
4091 }
4092 
4093 static void
4094 __nfs4_state_shutdown(void)
4095 {
4096 	int i;
4097 	struct nfs4_client *clp = NULL;
4098 	struct nfs4_delegation *dp = NULL;
4099 	struct list_head *pos, *next, reaplist;
4100 
4101 	for (i = 0; i < CLIENT_HASH_SIZE; i++) {
4102 		while (!list_empty(&conf_id_hashtbl[i])) {
4103 			clp = list_entry(conf_id_hashtbl[i].next, struct nfs4_client, cl_idhash);
4104 			expire_client(clp);
4105 		}
4106 		while (!list_empty(&unconf_str_hashtbl[i])) {
4107 			clp = list_entry(unconf_str_hashtbl[i].next, struct nfs4_client, cl_strhash);
4108 			expire_client(clp);
4109 		}
4110 	}
4111 	INIT_LIST_HEAD(&reaplist);
4112 	spin_lock(&recall_lock);
4113 	list_for_each_safe(pos, next, &del_recall_lru) {
4114 		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
4115 		list_move(&dp->dl_recall_lru, &reaplist);
4116 	}
4117 	spin_unlock(&recall_lock);
4118 	list_for_each_safe(pos, next, &reaplist) {
4119 		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
4120 		list_del_init(&dp->dl_recall_lru);
4121 		unhash_delegation(dp);
4122 	}
4123 
4124 	nfsd4_shutdown_recdir();
4125 	nfs4_init = 0;
4126 }
4127 
4128 void
4129 nfs4_state_shutdown(void)
4130 {
4131 	cancel_rearming_delayed_workqueue(laundry_wq, &laundromat_work);
4132 	destroy_workqueue(laundry_wq);
4133 	locks_end_grace(&nfsd4_manager);
4134 	nfs4_lock_state();
4135 	nfs4_release_reclaim();
4136 	__nfs4_state_shutdown();
4137 	nfs4_unlock_state();
4138 }
4139 
4140 /*
4141  * user_recovery_dirname is protected by the nfsd_mutex since it's only
4142  * accessed when nfsd is starting.
4143  */
4144 static void
4145 nfs4_set_recdir(char *recdir)
4146 {
4147 	strcpy(user_recovery_dirname, recdir);
4148 }
4149 
4150 /*
4151  * Change the NFSv4 recovery directory to recdir.
4152  */
4153 int
4154 nfs4_reset_recoverydir(char *recdir)
4155 {
4156 	int status;
4157 	struct path path;
4158 
4159 	status = kern_path(recdir, LOOKUP_FOLLOW, &path);
4160 	if (status)
4161 		return status;
4162 	status = -ENOTDIR;
4163 	if (S_ISDIR(path.dentry->d_inode->i_mode)) {
4164 		nfs4_set_recdir(recdir);
4165 		status = 0;
4166 	}
4167 	path_put(&path);
4168 	return status;
4169 }
4170 
4171 char *
4172 nfs4_recoverydir(void)
4173 {
4174 	return user_recovery_dirname;
4175 }
4176 
4177 /*
4178  * Called when leasetime is changed.
4179  *
4180  * The only way the protocol gives us to handle on-the-fly lease changes is to
4181  * simulate a reboot.  Instead of doing that, we just wait till the next time
4182  * we start to register any changes in lease time.  If the administrator
4183  * really wants to change the lease time *now*, they can go ahead and bring
4184  * nfsd down and then back up again after changing the lease time.
4185  *
4186  * user_lease_time is protected by nfsd_mutex since it's only really accessed
4187  * when nfsd is starting
4188  */
4189 void
4190 nfs4_reset_lease(time_t leasetime)
4191 {
4192 	user_lease_time = leasetime;
4193 }
4194