a95d260b713790214ef0865c20e15bb641290194
[linux-2.6.git] / fs / lockd / svclock.c
1 /*
2  * linux/fs/lockd/svclock.c
3  *
4  * Handling of server-side locks, mostly of the blocked variety.
5  * This is the ugliest part of lockd because we tread on very thin ice.
6  * GRANT and CANCEL calls may get stuck, meet in mid-flight, etc.
7  * IMNSHO introducing the grant callback into the NLM protocol was one
8  * of the worst ideas Sun ever had. Except maybe for the idea of doing
9  * NFS file locking at all.
10  *
11  * I'm trying hard to avoid race conditions by protecting most accesses
12  * to a file's list of blocked locks through a semaphore. The global
13  * list of blocked locks is not protected in this fashion however.
14  * Therefore, some functions (such as the RPC callback for the async grant
15  * call) move blocked locks towards the head of the list *while some other
16  * process might be traversing it*. This should not be a problem in
17  * practice, because this will only cause functions traversing the list
18  * to visit some blocks twice.
19  *
20  * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
21  */
22
23 #include <linux/config.h>
24 #include <linux/types.h>
25 #include <linux/errno.h>
26 #include <linux/kernel.h>
27 #include <linux/sched.h>
28 #include <linux/smp_lock.h>
29 #include <linux/sunrpc/clnt.h>
30 #include <linux/sunrpc/svc.h>
31 #include <linux/lockd/nlm.h>
32 #include <linux/lockd/lockd.h>
33
34 #define NLMDBG_FACILITY         NLMDBG_SVCLOCK
35
36 #ifdef CONFIG_LOCKD_V4
37 #define nlm_deadlock    nlm4_deadlock
38 #else
39 #define nlm_deadlock    nlm_lck_denied
40 #endif
41
42 static void nlmsvc_release_block(struct nlm_block *block);
43 static void     nlmsvc_insert_block(struct nlm_block *block, unsigned long);
44 static int      nlmsvc_remove_block(struct nlm_block *block);
45
46 static int nlmsvc_setgrantargs(struct nlm_rqst *call, struct nlm_lock *lock);
47 static void nlmsvc_freegrantargs(struct nlm_rqst *call);
48 static const struct rpc_call_ops nlmsvc_grant_ops;
49
50 /*
51  * The list of blocked locks to retry
52  */
53 static struct nlm_block *       nlm_blocked;
54
55 /*
56  * Insert a blocked lock into the global list
57  */
58 static void
59 nlmsvc_insert_block(struct nlm_block *block, unsigned long when)
60 {
61         struct nlm_block **bp, *b;
62
63         dprintk("lockd: nlmsvc_insert_block(%p, %ld)\n", block, when);
64         kref_get(&block->b_count);
65         if (block->b_queued)
66                 nlmsvc_remove_block(block);
67         bp = &nlm_blocked;
68         if (when != NLM_NEVER) {
69                 if ((when += jiffies) == NLM_NEVER)
70                         when ++;
71                 while ((b = *bp) && time_before_eq(b->b_when,when) && b->b_when != NLM_NEVER)
72                         bp = &b->b_next;
73         } else
74                 while ((b = *bp) != 0)
75                         bp = &b->b_next;
76
77         block->b_queued = 1;
78         block->b_when = when;
79         block->b_next = b;
80         *bp = block;
81 }
82
83 /*
84  * Remove a block from the global list
85  */
86 static int
87 nlmsvc_remove_block(struct nlm_block *block)
88 {
89         struct nlm_block **bp, *b;
90
91         if (!block->b_queued)
92                 return 1;
93         for (bp = &nlm_blocked; (b = *bp) != 0; bp = &b->b_next) {
94                 if (b == block) {
95                         *bp = block->b_next;
96                         block->b_queued = 0;
97                         nlmsvc_release_block(block);
98                         return 1;
99                 }
100         }
101
102         return 0;
103 }
104
105 /*
106  * Find a block for a given lock and optionally remove it from
107  * the list.
108  */
109 static struct nlm_block *
110 nlmsvc_lookup_block(struct nlm_file *file, struct nlm_lock *lock, int remove)
111 {
112         struct nlm_block        **head, *block;
113         struct file_lock        *fl;
114
115         dprintk("lockd: nlmsvc_lookup_block f=%p pd=%d %Ld-%Ld ty=%d\n",
116                                 file, lock->fl.fl_pid,
117                                 (long long)lock->fl.fl_start,
118                                 (long long)lock->fl.fl_end, lock->fl.fl_type);
119         for (head = &nlm_blocked; (block = *head) != 0; head = &block->b_next) {
120                 fl = &block->b_call.a_args.lock.fl;
121                 dprintk("lockd: check f=%p pd=%d %Ld-%Ld ty=%d cookie=%s\n",
122                                 block->b_file, fl->fl_pid,
123                                 (long long)fl->fl_start,
124                                 (long long)fl->fl_end, fl->fl_type,
125                                 nlmdbg_cookie2a(&block->b_call.a_args.cookie));
126                 if (block->b_file == file && nlm_compare_locks(fl, &lock->fl)) {
127                         if (remove) {
128                                 *head = block->b_next;
129                                 block->b_queued = 0;
130                         }
131                         kref_get(&block->b_count);
132                         return block;
133                 }
134         }
135
136         return NULL;
137 }
138
139 static inline int nlm_cookie_match(struct nlm_cookie *a, struct nlm_cookie *b)
140 {
141         if(a->len != b->len)
142                 return 0;
143         if(memcmp(a->data,b->data,a->len))
144                 return 0;
145         return 1;
146 }
147
148 /*
149  * Find a block with a given NLM cookie.
150  */
151 static inline struct nlm_block *
152 nlmsvc_find_block(struct nlm_cookie *cookie,  struct sockaddr_in *sin)
153 {
154         struct nlm_block *block;
155
156         for (block = nlm_blocked; block; block = block->b_next) {
157                 dprintk("cookie: head of blocked queue %p, block %p\n", 
158                         nlm_blocked, block);
159                 if (nlm_cookie_match(&block->b_call.a_args.cookie,cookie)
160                                 && nlm_cmp_addr(sin, &block->b_host->h_addr))
161                         break;
162         }
163
164         if (block != NULL)
165                 kref_get(&block->b_count);
166         return block;
167 }
168
169 /*
170  * Create a block and initialize it.
171  *
172  * Note: we explicitly set the cookie of the grant reply to that of
173  * the blocked lock request. The spec explicitly mentions that the client
174  * should _not_ rely on the callback containing the same cookie as the
175  * request, but (as I found out later) that's because some implementations
176  * do just this. Never mind the standards comittees, they support our
177  * logging industries.
178  */
179 static inline struct nlm_block *
180 nlmsvc_create_block(struct svc_rqst *rqstp, struct nlm_file *file,
181                                 struct nlm_lock *lock, struct nlm_cookie *cookie)
182 {
183         struct nlm_block        *block;
184         struct nlm_host         *host;
185         struct nlm_rqst         *call;
186
187         /* Create host handle for callback */
188         host = nlmsvc_lookup_host(rqstp);
189         if (host == NULL)
190                 return NULL;
191
192         /* Allocate memory for block, and initialize arguments */
193         if (!(block = (struct nlm_block *) kmalloc(sizeof(*block), GFP_KERNEL)))
194                 goto failed;
195         memset(block, 0, sizeof(*block));
196         locks_init_lock(&block->b_call.a_args.lock.fl);
197         locks_init_lock(&block->b_call.a_res.lock.fl);
198         kref_init(&block->b_count);
199
200         if (!nlmsvc_setgrantargs(&block->b_call, lock))
201                 goto failed_free;
202
203         /* Set notifier function for VFS, and init args */
204         block->b_call.a_args.lock.fl.fl_flags |= FL_SLEEP;
205         block->b_call.a_args.lock.fl.fl_lmops = &nlmsvc_lock_operations;
206         block->b_call.a_args.cookie = *cookie;  /* see above */
207
208         dprintk("lockd: created block %p...\n", block);
209
210         /* Create and initialize the block */
211         block->b_daemon = rqstp->rq_server;
212         block->b_host   = host;
213         block->b_file   = file;
214
215         /* Add to file's list of blocks */
216         block->b_fnext  = file->f_blocks;
217         file->f_blocks  = block;
218
219         /* Set up RPC arguments for callback */
220         call = &block->b_call;
221         call->a_host    = host;
222         call->a_flags   = RPC_TASK_ASYNC;
223
224         return block;
225
226 failed_free:
227         kfree(block);
228 failed:
229         nlm_release_host(host);
230         return NULL;
231 }
232
233 /*
234  * Delete a block. If the lock was cancelled or the grant callback
235  * failed, unlock is set to 1.
236  * It is the caller's responsibility to check whether the file
237  * can be closed hereafter.
238  */
239 static int nlmsvc_unlink_block(struct nlm_block *block)
240 {
241         int status;
242         dprintk("lockd: unlinking block %p...\n", block);
243
244         /* Remove block from list */
245         status = posix_unblock_lock(block->b_file->f_file, &block->b_call.a_args.lock.fl);
246         nlmsvc_remove_block(block);
247         return status;
248 }
249
250 static void nlmsvc_free_block(struct kref *kref)
251 {
252         struct nlm_block *block = container_of(kref, struct nlm_block, b_count);
253         struct nlm_file         *file = block->b_file;
254         struct nlm_block        **bp;
255
256         dprintk("lockd: freeing block %p...\n", block);
257
258         /* Remove block from file's list of blocks */
259         for (bp = &file->f_blocks; *bp; bp = &(*bp)->b_fnext) {
260                 if (*bp == block) {
261                         *bp = block->b_fnext;
262                         break;
263                 }
264         }
265
266         if (block->b_host)
267                 nlm_release_host(block->b_host);
268         nlmsvc_freegrantargs(&block->b_call);
269         kfree(block);
270 }
271
272 static void nlmsvc_release_block(struct nlm_block *block)
273 {
274         if (block != NULL)
275                 kref_put(&block->b_count, nlmsvc_free_block);
276 }
277
278 /*
279  * Loop over all blocks and perform the action specified.
280  * (NLM_ACT_CHECK handled by nlmsvc_inspect_file).
281  */
282 int
283 nlmsvc_traverse_blocks(struct nlm_host *host, struct nlm_file *file, int action)
284 {
285         struct nlm_block        *block, *next;
286         /* XXX: Will everything get cleaned up if we don't unlock here? */
287
288         down(&file->f_sema);
289         for (block = file->f_blocks; block; block = next) {
290                 next = block->b_fnext;
291                 if (action == NLM_ACT_MARK)
292                         block->b_host->h_inuse = 1;
293                 else if (action == NLM_ACT_UNLOCK) {
294                         if (host == NULL || host == block->b_host)
295                                 nlmsvc_unlink_block(block);
296                 }
297         }
298         up(&file->f_sema);
299         return 0;
300 }
301
302 /*
303  * Initialize arguments for GRANTED call. The nlm_rqst structure
304  * has been cleared already.
305  */
306 static int nlmsvc_setgrantargs(struct nlm_rqst *call, struct nlm_lock *lock)
307 {
308         locks_copy_lock(&call->a_args.lock.fl, &lock->fl);
309         memcpy(&call->a_args.lock.fh, &lock->fh, sizeof(call->a_args.lock.fh));
310         call->a_args.lock.caller = system_utsname.nodename;
311         call->a_args.lock.oh.len = lock->oh.len;
312
313         /* set default data area */
314         call->a_args.lock.oh.data = call->a_owner;
315         call->a_args.lock.svid = lock->fl.fl_pid;
316
317         if (lock->oh.len > NLMCLNT_OHSIZE) {
318                 void *data = kmalloc(lock->oh.len, GFP_KERNEL);
319                 if (!data) {
320                         nlmsvc_freegrantargs(call);
321                         return 0;
322                 }
323                 call->a_args.lock.oh.data = (u8 *) data;
324         }
325
326         memcpy(call->a_args.lock.oh.data, lock->oh.data, lock->oh.len);
327         return 1;
328 }
329
330 static void nlmsvc_freegrantargs(struct nlm_rqst *call)
331 {
332         struct file_lock *fl = &call->a_args.lock.fl;
333         /*
334          * Check whether we allocated memory for the owner.
335          */
336         if (call->a_args.lock.oh.data != (u8 *) call->a_owner) {
337                 kfree(call->a_args.lock.oh.data);
338         }
339         if (fl->fl_ops && fl->fl_ops->fl_release_private)
340                 fl->fl_ops->fl_release_private(fl);
341         if (fl->fl_lmops && fl->fl_lmops->fl_release_private)
342                 fl->fl_lmops->fl_release_private(fl);
343 }
344
345 /*
346  * Attempt to establish a lock, and if it can't be granted, block it
347  * if required.
348  */
349 u32
350 nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
351                         struct nlm_lock *lock, int wait, struct nlm_cookie *cookie)
352 {
353         struct nlm_block        *block, *newblock = NULL;
354         int                     error;
355         u32                     ret;
356
357         dprintk("lockd: nlmsvc_lock(%s/%ld, ty=%d, pi=%d, %Ld-%Ld, bl=%d)\n",
358                                 file->f_file->f_dentry->d_inode->i_sb->s_id,
359                                 file->f_file->f_dentry->d_inode->i_ino,
360                                 lock->fl.fl_type, lock->fl.fl_pid,
361                                 (long long)lock->fl.fl_start,
362                                 (long long)lock->fl.fl_end,
363                                 wait);
364
365
366         lock->fl.fl_flags &= ~FL_SLEEP;
367 again:
368         /* Lock file against concurrent access */
369         down(&file->f_sema);
370         /* Get existing block (in case client is busy-waiting) */
371         block = nlmsvc_lookup_block(file, lock, 0);
372         if (block == NULL) {
373                 if (newblock != NULL)
374                         lock = &newblock->b_call.a_args.lock;
375         } else
376                 lock = &block->b_call.a_args.lock;
377
378         error = posix_lock_file(file->f_file, &lock->fl);
379         lock->fl.fl_flags &= ~FL_SLEEP;
380
381         dprintk("lockd: posix_lock_file returned %d\n", error);
382
383         switch(error) {
384                 case 0:
385                         ret = nlm_granted;
386                         goto out;
387                 case -EAGAIN:
388                         break;
389                 case -EDEADLK:
390                         ret = nlm_deadlock;
391                         goto out;
392                 default:                        /* includes ENOLCK */
393                         ret = nlm_lck_denied_nolocks;
394                         goto out;
395         }
396
397         ret = nlm_lck_denied;
398         if (!wait)
399                 goto out;
400
401         ret = nlm_lck_blocked;
402         if (block != NULL)
403                 goto out;
404
405         /* If we don't have a block, create and initialize it. Then
406          * retry because we may have slept in kmalloc. */
407         /* We have to release f_sema as nlmsvc_create_block may try to
408          * to claim it while doing host garbage collection */
409         if (newblock == NULL) {
410                 up(&file->f_sema);
411                 dprintk("lockd: blocking on this lock (allocating).\n");
412                 if (!(newblock = nlmsvc_create_block(rqstp, file, lock, cookie)))
413                         return nlm_lck_denied_nolocks;
414                 goto again;
415         }
416
417         /* Append to list of blocked */
418         nlmsvc_insert_block(newblock, NLM_NEVER);
419 out:
420         up(&file->f_sema);
421         nlmsvc_release_block(newblock);
422         nlmsvc_release_block(block);
423         dprintk("lockd: nlmsvc_lock returned %u\n", ret);
424         return ret;
425 }
426
427 /*
428  * Test for presence of a conflicting lock.
429  */
430 u32
431 nlmsvc_testlock(struct nlm_file *file, struct nlm_lock *lock,
432                                        struct nlm_lock *conflock)
433 {
434         dprintk("lockd: nlmsvc_testlock(%s/%ld, ty=%d, %Ld-%Ld)\n",
435                                 file->f_file->f_dentry->d_inode->i_sb->s_id,
436                                 file->f_file->f_dentry->d_inode->i_ino,
437                                 lock->fl.fl_type,
438                                 (long long)lock->fl.fl_start,
439                                 (long long)lock->fl.fl_end);
440
441         if (posix_test_lock(file->f_file, &lock->fl, &conflock->fl)) {
442                 dprintk("lockd: conflicting lock(ty=%d, %Ld-%Ld)\n",
443                                 conflock->fl.fl_type,
444                                 (long long)conflock->fl.fl_start,
445                                 (long long)conflock->fl.fl_end);
446                 conflock->caller = "somehost";  /* FIXME */
447                 conflock->oh.len = 0;           /* don't return OH info */
448                 conflock->svid = conflock->fl.fl_pid;
449                 return nlm_lck_denied;
450         }
451
452         return nlm_granted;
453 }
454
455 /*
456  * Remove a lock.
457  * This implies a CANCEL call: We send a GRANT_MSG, the client replies
458  * with a GRANT_RES call which gets lost, and calls UNLOCK immediately
459  * afterwards. In this case the block will still be there, and hence
460  * must be removed.
461  */
462 u32
463 nlmsvc_unlock(struct nlm_file *file, struct nlm_lock *lock)
464 {
465         int     error;
466
467         dprintk("lockd: nlmsvc_unlock(%s/%ld, pi=%d, %Ld-%Ld)\n",
468                                 file->f_file->f_dentry->d_inode->i_sb->s_id,
469                                 file->f_file->f_dentry->d_inode->i_ino,
470                                 lock->fl.fl_pid,
471                                 (long long)lock->fl.fl_start,
472                                 (long long)lock->fl.fl_end);
473
474         /* First, cancel any lock that might be there */
475         nlmsvc_cancel_blocked(file, lock);
476
477         lock->fl.fl_type = F_UNLCK;
478         error = posix_lock_file(file->f_file, &lock->fl);
479
480         return (error < 0)? nlm_lck_denied_nolocks : nlm_granted;
481 }
482
483 /*
484  * Cancel a previously blocked request.
485  *
486  * A cancel request always overrides any grant that may currently
487  * be in progress.
488  * The calling procedure must check whether the file can be closed.
489  */
490 u32
491 nlmsvc_cancel_blocked(struct nlm_file *file, struct nlm_lock *lock)
492 {
493         struct nlm_block        *block;
494         int status = 0;
495
496         dprintk("lockd: nlmsvc_cancel(%s/%ld, pi=%d, %Ld-%Ld)\n",
497                                 file->f_file->f_dentry->d_inode->i_sb->s_id,
498                                 file->f_file->f_dentry->d_inode->i_ino,
499                                 lock->fl.fl_pid,
500                                 (long long)lock->fl.fl_start,
501                                 (long long)lock->fl.fl_end);
502
503         down(&file->f_sema);
504         if ((block = nlmsvc_lookup_block(file, lock, 1)) != NULL) {
505                 status = nlmsvc_unlink_block(block);
506                 nlmsvc_release_block(block);
507         }
508         up(&file->f_sema);
509         return status ? nlm_lck_denied : nlm_granted;
510 }
511
512 /*
513  * Unblock a blocked lock request. This is a callback invoked from the
514  * VFS layer when a lock on which we blocked is removed.
515  *
516  * This function doesn't grant the blocked lock instantly, but rather moves
517  * the block to the head of nlm_blocked where it can be picked up by lockd.
518  */
519 static void
520 nlmsvc_notify_blocked(struct file_lock *fl)
521 {
522         struct nlm_block        **bp, *block;
523
524         dprintk("lockd: VFS unblock notification for block %p\n", fl);
525         for (bp = &nlm_blocked; (block = *bp) != 0; bp = &block->b_next) {
526                 if (nlm_compare_locks(&block->b_call.a_args.lock.fl, fl)) {
527                         nlmsvc_insert_block(block, 0);
528                         svc_wake_up(block->b_daemon);
529                         return;
530                 }
531         }
532
533         printk(KERN_WARNING "lockd: notification for unknown block!\n");
534 }
535
536 static int nlmsvc_same_owner(struct file_lock *fl1, struct file_lock *fl2)
537 {
538         return fl1->fl_owner == fl2->fl_owner && fl1->fl_pid == fl2->fl_pid;
539 }
540
541 struct lock_manager_operations nlmsvc_lock_operations = {
542         .fl_compare_owner = nlmsvc_same_owner,
543         .fl_notify = nlmsvc_notify_blocked,
544 };
545
546 /*
547  * Try to claim a lock that was previously blocked.
548  *
549  * Note that we use both the RPC_GRANTED_MSG call _and_ an async
550  * RPC thread when notifying the client. This seems like overkill...
551  * Here's why:
552  *  -   we don't want to use a synchronous RPC thread, otherwise
553  *      we might find ourselves hanging on a dead portmapper.
554  *  -   Some lockd implementations (e.g. HP) don't react to
555  *      RPC_GRANTED calls; they seem to insist on RPC_GRANTED_MSG calls.
556  */
557 static void
558 nlmsvc_grant_blocked(struct nlm_block *block)
559 {
560         struct nlm_file         *file = block->b_file;
561         struct nlm_lock         *lock = &block->b_call.a_args.lock;
562         int                     error;
563
564         dprintk("lockd: grant blocked lock %p\n", block);
565
566         /* First thing is lock the file */
567         down(&file->f_sema);
568
569         /* Unlink block request from list */
570         nlmsvc_unlink_block(block);
571
572         /* If b_granted is true this means we've been here before.
573          * Just retry the grant callback, possibly refreshing the RPC
574          * binding */
575         if (block->b_granted) {
576                 nlm_rebind_host(block->b_host);
577                 goto callback;
578         }
579
580         /* Try the lock operation again */
581         lock->fl.fl_flags |= FL_SLEEP;
582         error = posix_lock_file(file->f_file, &lock->fl);
583         lock->fl.fl_flags &= ~FL_SLEEP;
584
585         switch (error) {
586         case 0:
587                 break;
588         case -EAGAIN:
589                 dprintk("lockd: lock still blocked\n");
590                 nlmsvc_insert_block(block, NLM_NEVER);
591                 goto out_unlock;
592         default:
593                 printk(KERN_WARNING "lockd: unexpected error %d in %s!\n",
594                                 -error, __FUNCTION__);
595                 nlmsvc_insert_block(block, 10 * HZ);
596                 goto out_unlock;
597         }
598
599 callback:
600         /* Lock was granted by VFS. */
601         dprintk("lockd: GRANTing blocked lock.\n");
602         block->b_granted = 1;
603
604         /* Schedule next grant callback in 30 seconds */
605         nlmsvc_insert_block(block, 30 * HZ);
606
607         /* Call the client */
608         kref_get(&block->b_count);
609         if (nlmsvc_async_call(&block->b_call, NLMPROC_GRANTED_MSG,
610                                                 &nlmsvc_grant_ops) < 0)
611                 nlmsvc_release_block(block);
612 out_unlock:
613         up(&file->f_sema);
614 }
615
616 /*
617  * This is the callback from the RPC layer when the NLM_GRANTED_MSG
618  * RPC call has succeeded or timed out.
619  * Like all RPC callbacks, it is invoked by the rpciod process, so it
620  * better not sleep. Therefore, we put the blocked lock on the nlm_blocked
621  * chain once more in order to have it removed by lockd itself (which can
622  * then sleep on the file semaphore without disrupting e.g. the nfs client).
623  */
624 static void nlmsvc_grant_callback(struct rpc_task *task, void *data)
625 {
626         struct nlm_rqst         *call = data;
627         struct nlm_block        *block = container_of(call, struct nlm_block, b_call);
628         unsigned long           timeout;
629
630         dprintk("lockd: GRANT_MSG RPC callback\n");
631
632         /* Technically, we should down the file semaphore here. Since we
633          * move the block towards the head of the queue only, no harm
634          * can be done, though. */
635         if (task->tk_status < 0) {
636                 /* RPC error: Re-insert for retransmission */
637                 timeout = 10 * HZ;
638         } else if (block->b_done) {
639                 /* Block already removed, kill it for real */
640                 timeout = 0;
641         } else {
642                 /* Call was successful, now wait for client callback */
643                 timeout = 60 * HZ;
644         }
645         nlmsvc_insert_block(block, timeout);
646         svc_wake_up(block->b_daemon);
647 }
648
649 void nlmsvc_grant_release(void *data)
650 {
651         nlmsvc_release_block(data);
652 }
653
654 static const struct rpc_call_ops nlmsvc_grant_ops = {
655         .rpc_call_done = nlmsvc_grant_callback,
656         .rpc_release = nlmsvc_grant_release,
657 };
658
659 /*
660  * We received a GRANT_RES callback. Try to find the corresponding
661  * block.
662  */
663 void
664 nlmsvc_grant_reply(struct svc_rqst *rqstp, struct nlm_cookie *cookie, u32 status)
665 {
666         struct nlm_block        *block;
667         struct nlm_file         *file;
668
669         dprintk("grant_reply: looking for cookie %x, host (%08x), s=%d \n", 
670                 *(unsigned int *)(cookie->data), 
671                 ntohl(rqstp->rq_addr.sin_addr.s_addr), status);
672         if (!(block = nlmsvc_find_block(cookie, &rqstp->rq_addr)))
673                 return;
674         file = block->b_file;
675
676         file->f_count++;
677         down(&file->f_sema);
678         if (block) {
679                 if (status == NLM_LCK_DENIED_GRACE_PERIOD) {
680                         /* Try again in a couple of seconds */
681                         nlmsvc_insert_block(block, 10 * HZ);
682                 } else {
683                         /* Lock is now held by client, or has been rejected.
684                          * In both cases, the block should be removed. */
685                         nlmsvc_unlink_block(block);
686                 }
687         }
688         up(&file->f_sema);
689         nlm_release_file(file);
690         nlmsvc_release_block(block);
691 }
692
693 /*
694  * Retry all blocked locks that have been notified. This is where lockd
695  * picks up locks that can be granted, or grant notifications that must
696  * be retransmitted.
697  */
698 unsigned long
699 nlmsvc_retry_blocked(void)
700 {
701         struct nlm_block        *block;
702
703         dprintk("nlmsvc_retry_blocked(%p, when=%ld)\n",
704                         nlm_blocked,
705                         nlm_blocked? nlm_blocked->b_when : 0);
706         while ((block = nlm_blocked) != 0) {
707                 if (block->b_when == NLM_NEVER)
708                         break;
709                 if (time_after(block->b_when,jiffies))
710                         break;
711                 dprintk("nlmsvc_retry_blocked(%p, when=%ld, done=%d)\n",
712                         block, block->b_when, block->b_done);
713                 kref_get(&block->b_count);
714                 if (block->b_done)
715                         nlmsvc_unlink_block(block);
716                 else
717                         nlmsvc_grant_blocked(block);
718                 nlmsvc_release_block(block);
719         }
720
721         if ((block = nlm_blocked) && block->b_when != NLM_NEVER)
722                 return (block->b_when - jiffies);
723
724         return MAX_SCHEDULE_TIMEOUT;
725 }