1 /* AFS file locking support
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
14 #define AFS_LOCK_GRANTED 0
15 #define AFS_LOCK_PENDING 1
16 #define AFS_LOCK_YOUR_TRY 2
18 struct workqueue_struct *afs_lock_manager;
20 static void afs_next_locker(struct afs_vnode *vnode, int error);
21 static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl);
22 static void afs_fl_release_private(struct file_lock *fl);
24 static const struct file_lock_operations afs_lock_ops = {
25 .fl_copy_lock = afs_fl_copy_lock,
26 .fl_release_private = afs_fl_release_private,
29 static inline void afs_set_lock_state(struct afs_vnode *vnode, enum afs_lock_state state)
31 _debug("STATE %u -> %u", vnode->lock_state, state);
32 vnode->lock_state = state;
35 static atomic_t afs_file_lock_debug_id;
38 * if the callback is broken on this vnode, then the lock may now be available
40 void afs_lock_may_be_available(struct afs_vnode *vnode)
42 _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
44 spin_lock(&vnode->lock);
45 if (vnode->lock_state == AFS_VNODE_LOCK_WAITING_FOR_CB)
46 afs_next_locker(vnode, 0);
47 trace_afs_flock_ev(vnode, NULL, afs_flock_callback_break, 0);
48 spin_unlock(&vnode->lock);
52 * the lock will time out in 5 minutes unless we extend it, so schedule
53 * extension in a bit less than that time
55 static void afs_schedule_lock_extension(struct afs_vnode *vnode)
57 ktime_t expires_at, now, duration;
60 expires_at = ktime_add_ms(vnode->locked_at, AFS_LOCKWAIT * 1000 / 2);
61 now = ktime_get_real();
62 duration = ktime_sub(expires_at, now);
66 duration_j = nsecs_to_jiffies(ktime_to_ns(duration));
68 queue_delayed_work(afs_lock_manager, &vnode->lock_work, duration_j);
72 * In the case of successful completion of a lock operation, record the time
73 * the reply appeared and start the lock extension timer.
75 void afs_lock_op_done(struct afs_call *call)
77 struct afs_vnode *vnode = call->xvnode;
79 if (call->error == 0) {
80 spin_lock(&vnode->lock);
81 trace_afs_flock_ev(vnode, NULL, afs_flock_timestamp, 0);
82 vnode->locked_at = call->reply_time;
83 afs_schedule_lock_extension(vnode);
84 spin_unlock(&vnode->lock);
89 * grant one or more locks (readlocks are allowed to jump the queue if the
90 * first lock in the queue is itself a readlock)
91 * - the caller must hold the vnode lock
93 static void afs_grant_locks(struct afs_vnode *vnode)
95 struct file_lock *p, *_p;
96 bool exclusive = (vnode->lock_type == AFS_LOCK_WRITE);
98 list_for_each_entry_safe(p, _p, &vnode->pending_locks, fl_u.afs.link) {
99 if (!exclusive && p->fl_type == F_WRLCK)
102 list_move_tail(&p->fl_u.afs.link, &vnode->granted_locks);
103 p->fl_u.afs.state = AFS_LOCK_GRANTED;
104 trace_afs_flock_op(vnode, p, afs_flock_op_grant);
105 wake_up(&p->fl_wait);
110 * If an error is specified, reject every pending lock that matches the
111 * authentication and type of the lock we failed to get. If there are any
112 * remaining lockers, try to wake up one of them to have a go.
114 static void afs_next_locker(struct afs_vnode *vnode, int error)
116 struct file_lock *p, *_p, *next = NULL;
117 struct key *key = vnode->lock_key;
118 unsigned int fl_type = F_RDLCK;
122 if (vnode->lock_type == AFS_LOCK_WRITE)
125 list_for_each_entry_safe(p, _p, &vnode->pending_locks, fl_u.afs.link) {
127 p->fl_type == fl_type &&
128 afs_file_key(p->fl_file) == key) {
129 list_del_init(&p->fl_u.afs.link);
130 p->fl_u.afs.state = error;
131 wake_up(&p->fl_wait);
134 /* Select the next locker to hand off to. */
136 (next->fl_type == F_WRLCK || p->fl_type == F_RDLCK))
141 vnode->lock_key = NULL;
145 afs_set_lock_state(vnode, AFS_VNODE_LOCK_SETTING);
146 next->fl_u.afs.state = AFS_LOCK_YOUR_TRY;
147 trace_afs_flock_op(vnode, next, afs_flock_op_wake);
148 wake_up(&next->fl_wait);
150 afs_set_lock_state(vnode, AFS_VNODE_LOCK_NONE);
151 trace_afs_flock_ev(vnode, NULL, afs_flock_no_lockers, 0);
158 * Kill off all waiters in the the pending lock queue due to the vnode being
161 static void afs_kill_lockers_enoent(struct afs_vnode *vnode)
165 afs_set_lock_state(vnode, AFS_VNODE_LOCK_DELETED);
167 while (!list_empty(&vnode->pending_locks)) {
168 p = list_entry(vnode->pending_locks.next,
169 struct file_lock, fl_u.afs.link);
170 list_del_init(&p->fl_u.afs.link);
171 p->fl_u.afs.state = -ENOENT;
172 wake_up(&p->fl_wait);
175 key_put(vnode->lock_key);
176 vnode->lock_key = NULL;
180 * Get a lock on a file
182 static int afs_set_lock(struct afs_vnode *vnode, struct key *key,
183 afs_lock_type_t type)
185 struct afs_fs_cursor fc;
188 _enter("%s{%llx:%llu.%u},%x,%u",
193 key_serial(key), type);
196 if (afs_begin_vnode_operation(&fc, vnode, key, true)) {
197 while (afs_select_fileserver(&fc)) {
198 fc.cb_break = afs_calc_vnode_cb_break(vnode);
199 afs_fs_set_lock(&fc, type);
202 afs_check_for_remote_deletion(&fc, fc.vnode);
203 afs_vnode_commit_status(&fc, vnode, fc.cb_break);
204 ret = afs_end_vnode_operation(&fc);
207 _leave(" = %d", ret);
212 * Extend a lock on a file
214 static int afs_extend_lock(struct afs_vnode *vnode, struct key *key)
216 struct afs_fs_cursor fc;
219 _enter("%s{%llx:%llu.%u},%x",
227 if (afs_begin_vnode_operation(&fc, vnode, key, false)) {
228 while (afs_select_current_fileserver(&fc)) {
229 fc.cb_break = afs_calc_vnode_cb_break(vnode);
230 afs_fs_extend_lock(&fc);
233 afs_check_for_remote_deletion(&fc, fc.vnode);
234 afs_vnode_commit_status(&fc, vnode, fc.cb_break);
235 ret = afs_end_vnode_operation(&fc);
238 _leave(" = %d", ret);
243 * Release a lock on a file
245 static int afs_release_lock(struct afs_vnode *vnode, struct key *key)
247 struct afs_fs_cursor fc;
250 _enter("%s{%llx:%llu.%u},%x",
258 if (afs_begin_vnode_operation(&fc, vnode, key, false)) {
259 while (afs_select_current_fileserver(&fc)) {
260 fc.cb_break = afs_calc_vnode_cb_break(vnode);
261 afs_fs_release_lock(&fc);
264 afs_check_for_remote_deletion(&fc, fc.vnode);
265 afs_vnode_commit_status(&fc, vnode, fc.cb_break);
266 ret = afs_end_vnode_operation(&fc);
269 _leave(" = %d", ret);
274 * do work for a lock, including:
275 * - probing for a lock we're waiting on but didn't get immediately
276 * - extending a lock that's close to timing out
278 void afs_lock_work(struct work_struct *work)
280 struct afs_vnode *vnode =
281 container_of(work, struct afs_vnode, lock_work.work);
285 _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
287 spin_lock(&vnode->lock);
290 _debug("wstate %u for %p", vnode->lock_state, vnode);
291 switch (vnode->lock_state) {
292 case AFS_VNODE_LOCK_NEED_UNLOCK:
293 afs_set_lock_state(vnode, AFS_VNODE_LOCK_UNLOCKING);
294 trace_afs_flock_ev(vnode, NULL, afs_flock_work_unlocking, 0);
295 spin_unlock(&vnode->lock);
297 /* attempt to release the server lock; if it fails, we just
298 * wait 5 minutes and it'll expire anyway */
299 ret = afs_release_lock(vnode, vnode->lock_key);
300 if (ret < 0 && vnode->lock_state != AFS_VNODE_LOCK_DELETED) {
301 trace_afs_flock_ev(vnode, NULL, afs_flock_release_fail,
303 printk(KERN_WARNING "AFS:"
304 " Failed to release lock on {%llx:%llx} error %d\n",
305 vnode->fid.vid, vnode->fid.vnode, ret);
308 spin_lock(&vnode->lock);
310 afs_kill_lockers_enoent(vnode);
312 afs_next_locker(vnode, 0);
313 spin_unlock(&vnode->lock);
316 /* If we've already got a lock, then it must be time to extend that
317 * lock as AFS locks time out after 5 minutes.
319 case AFS_VNODE_LOCK_GRANTED:
322 ASSERT(!list_empty(&vnode->granted_locks));
324 key = key_get(vnode->lock_key);
325 afs_set_lock_state(vnode, AFS_VNODE_LOCK_EXTENDING);
326 trace_afs_flock_ev(vnode, NULL, afs_flock_work_extending, 0);
327 spin_unlock(&vnode->lock);
329 ret = afs_extend_lock(vnode, key); /* RPC */
333 trace_afs_flock_ev(vnode, NULL, afs_flock_extend_fail,
335 pr_warning("AFS: Failed to extend lock on {%llx:%llx} error %d\n",
336 vnode->fid.vid, vnode->fid.vnode, ret);
339 spin_lock(&vnode->lock);
341 if (ret == -ENOENT) {
342 afs_kill_lockers_enoent(vnode);
343 spin_unlock(&vnode->lock);
347 if (vnode->lock_state != AFS_VNODE_LOCK_EXTENDING)
349 afs_set_lock_state(vnode, AFS_VNODE_LOCK_GRANTED);
352 queue_delayed_work(afs_lock_manager, &vnode->lock_work,
354 spin_unlock(&vnode->lock);
358 /* If we're waiting for a callback to indicate lock release, we can't
359 * actually rely on this, so need to recheck at regular intervals. The
360 * problem is that the server might not notify us if the lock just
361 * expires (say because a client died) rather than being explicitly
364 case AFS_VNODE_LOCK_WAITING_FOR_CB:
366 afs_next_locker(vnode, 0);
367 spin_unlock(&vnode->lock);
370 case AFS_VNODE_LOCK_DELETED:
371 afs_kill_lockers_enoent(vnode);
372 spin_unlock(&vnode->lock);
377 /* Looks like a lock request was withdrawn. */
378 spin_unlock(&vnode->lock);
385 * pass responsibility for the unlocking of a vnode on the server to the
386 * manager thread, lest a pending signal in the calling thread interrupt
388 * - the caller must hold the vnode lock
390 static void afs_defer_unlock(struct afs_vnode *vnode)
392 _enter("%u", vnode->lock_state);
394 if (list_empty(&vnode->granted_locks) &&
395 (vnode->lock_state == AFS_VNODE_LOCK_GRANTED ||
396 vnode->lock_state == AFS_VNODE_LOCK_EXTENDING)) {
397 cancel_delayed_work(&vnode->lock_work);
399 afs_set_lock_state(vnode, AFS_VNODE_LOCK_NEED_UNLOCK);
400 trace_afs_flock_ev(vnode, NULL, afs_flock_defer_unlock, 0);
401 queue_delayed_work(afs_lock_manager, &vnode->lock_work, 0);
406 * Check that our view of the file metadata is up to date and check to see
407 * whether we think that we have a locking permit.
409 static int afs_do_setlk_check(struct afs_vnode *vnode, struct key *key,
410 enum afs_flock_mode mode, afs_lock_type_t type)
415 /* Make sure we've got a callback on this file and that our view of the
416 * data version is up to date.
418 ret = afs_validate(vnode, key);
422 /* Check the permission set to see if we're actually going to be
423 * allowed to get a lock on this file.
425 ret = afs_check_permit(vnode, key, &access);
429 /* At a rough estimation, you need LOCK, WRITE or INSERT perm to
430 * read-lock a file and WRITE or INSERT perm to write-lock a file.
432 * We can't rely on the server to do this for us since if we want to
433 * share a read lock that we already have, we won't go the server.
435 if (type == AFS_LOCK_READ) {
436 if (!(access & (AFS_ACE_INSERT | AFS_ACE_WRITE | AFS_ACE_LOCK)))
439 if (!(access & (AFS_ACE_INSERT | AFS_ACE_WRITE)))
447 * request a lock on a file on the server
449 static int afs_do_setlk(struct file *file, struct file_lock *fl)
451 struct inode *inode = locks_inode(file);
452 struct afs_vnode *vnode = AFS_FS_I(inode);
453 enum afs_flock_mode mode = AFS_FS_S(inode->i_sb)->flock_mode;
454 afs_lock_type_t type;
455 struct key *key = afs_file_key(file);
456 bool partial, no_server_lock = false;
459 if (mode == afs_flock_mode_unset)
460 mode = afs_flock_mode_openafs;
462 _enter("{%llx:%llu},%llu-%llu,%u,%u",
463 vnode->fid.vid, vnode->fid.vnode,
464 fl->fl_start, fl->fl_end, fl->fl_type, mode);
466 fl->fl_ops = &afs_lock_ops;
467 INIT_LIST_HEAD(&fl->fl_u.afs.link);
468 fl->fl_u.afs.state = AFS_LOCK_PENDING;
470 partial = (fl->fl_start != 0 || fl->fl_end != OFFSET_MAX);
471 type = (fl->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE;
472 if (mode == afs_flock_mode_write && partial)
473 type = AFS_LOCK_WRITE;
475 ret = afs_do_setlk_check(vnode, key, mode, type);
479 trace_afs_flock_op(vnode, fl, afs_flock_op_set_lock);
481 /* AFS3 protocol only supports full-file locks and doesn't provide any
482 * method of upgrade/downgrade, so we need to emulate for partial-file
485 * The OpenAFS client only gets a server lock for a full-file lock and
486 * keeps partial-file locks local. Allow this behaviour to be emulated
489 if (mode == afs_flock_mode_local ||
490 (partial && mode == afs_flock_mode_openafs)) {
491 no_server_lock = true;
492 goto skip_server_lock;
495 spin_lock(&vnode->lock);
496 list_add_tail(&fl->fl_u.afs.link, &vnode->pending_locks);
499 if (vnode->lock_state == AFS_VNODE_LOCK_DELETED)
502 /* If we've already got a lock on the server then try to move to having
503 * the VFS grant the requested lock. Note that this means that other
504 * clients may get starved out.
506 _debug("try %u", vnode->lock_state);
507 if (vnode->lock_state == AFS_VNODE_LOCK_GRANTED) {
508 if (type == AFS_LOCK_READ) {
509 _debug("instant readlock");
510 list_move_tail(&fl->fl_u.afs.link, &vnode->granted_locks);
511 fl->fl_u.afs.state = AFS_LOCK_GRANTED;
512 goto vnode_is_locked_u;
515 if (vnode->lock_type == AFS_LOCK_WRITE) {
516 _debug("instant writelock");
517 list_move_tail(&fl->fl_u.afs.link, &vnode->granted_locks);
518 fl->fl_u.afs.state = AFS_LOCK_GRANTED;
519 goto vnode_is_locked_u;
523 if (vnode->lock_state == AFS_VNODE_LOCK_NONE &&
524 !(fl->fl_flags & FL_SLEEP)) {
526 if (type == AFS_LOCK_READ) {
527 if (vnode->status.lock_count == -1)
528 goto lock_is_contended; /* Write locked */
530 if (vnode->status.lock_count != 0)
531 goto lock_is_contended; /* Locked */
535 if (vnode->lock_state != AFS_VNODE_LOCK_NONE)
539 /* We don't have a lock on this vnode and we aren't currently waiting
540 * for one either, so ask the server for a lock.
542 * Note that we need to be careful if we get interrupted by a signal
543 * after dispatching the request as we may still get the lock, even
544 * though we don't wait for the reply (it's not too bad a problem - the
545 * lock will expire in 5 mins anyway).
547 trace_afs_flock_ev(vnode, fl, afs_flock_try_to_lock, 0);
548 vnode->lock_key = key_get(key);
549 vnode->lock_type = type;
550 afs_set_lock_state(vnode, AFS_VNODE_LOCK_SETTING);
551 spin_unlock(&vnode->lock);
553 ret = afs_set_lock(vnode, key, type); /* RPC */
555 spin_lock(&vnode->lock);
562 fl->fl_u.afs.state = ret;
563 trace_afs_flock_ev(vnode, fl, afs_flock_fail_perm, ret);
564 list_del_init(&fl->fl_u.afs.link);
565 afs_next_locker(vnode, ret);
569 fl->fl_u.afs.state = ret;
570 trace_afs_flock_ev(vnode, fl, afs_flock_fail_other, ret);
571 list_del_init(&fl->fl_u.afs.link);
572 afs_kill_lockers_enoent(vnode);
576 fl->fl_u.afs.state = ret;
577 trace_afs_flock_ev(vnode, fl, afs_flock_fail_other, ret);
578 list_del_init(&fl->fl_u.afs.link);
579 afs_next_locker(vnode, 0);
583 /* The server doesn't have a lock-waiting queue, so the client
584 * will have to retry. The server will break the outstanding
585 * callbacks on a file when a lock is released.
587 ASSERT(list_empty(&vnode->granted_locks));
588 ASSERTCMP(vnode->pending_locks.next, ==, &fl->fl_u.afs.link);
589 goto lock_is_contended;
592 afs_set_lock_state(vnode, AFS_VNODE_LOCK_GRANTED);
593 trace_afs_flock_ev(vnode, fl, afs_flock_acquired, type);
594 afs_grant_locks(vnode);
595 goto vnode_is_locked_u;
599 spin_unlock(&vnode->lock);
601 /* the lock has been granted by the server... */
602 ASSERTCMP(fl->fl_u.afs.state, ==, AFS_LOCK_GRANTED);
605 /* ... but the VFS still needs to distribute access on this client. */
606 trace_afs_flock_ev(vnode, fl, afs_flock_vfs_locking, 0);
607 ret = locks_lock_file_wait(file, fl);
608 trace_afs_flock_ev(vnode, fl, afs_flock_vfs_lock, ret);
610 goto vfs_rejected_lock;
612 /* Again, make sure we've got a callback on this file and, again, make
613 * sure that our view of the data version is up to date (we ignore
614 * errors incurred here and deal with the consequences elsewhere).
616 afs_validate(vnode, key);
621 if (!(fl->fl_flags & FL_SLEEP)) {
622 list_del_init(&fl->fl_u.afs.link);
623 afs_next_locker(vnode, 0);
628 afs_set_lock_state(vnode, AFS_VNODE_LOCK_WAITING_FOR_CB);
629 trace_afs_flock_ev(vnode, fl, afs_flock_would_block, ret);
630 queue_delayed_work(afs_lock_manager, &vnode->lock_work, HZ * 5);
633 /* We're going to have to wait. Either this client doesn't have a lock
634 * on the server yet and we need to wait for a callback to occur, or
635 * the client does have a lock on the server, but it's shared and we
636 * need an exclusive lock.
638 spin_unlock(&vnode->lock);
640 trace_afs_flock_ev(vnode, fl, afs_flock_waiting, 0);
641 ret = wait_event_interruptible(fl->fl_wait,
642 fl->fl_u.afs.state != AFS_LOCK_PENDING);
643 trace_afs_flock_ev(vnode, fl, afs_flock_waited, ret);
645 if (fl->fl_u.afs.state >= 0 && fl->fl_u.afs.state != AFS_LOCK_GRANTED) {
646 spin_lock(&vnode->lock);
648 switch (fl->fl_u.afs.state) {
649 case AFS_LOCK_YOUR_TRY:
650 fl->fl_u.afs.state = AFS_LOCK_PENDING;
652 case AFS_LOCK_PENDING:
654 /* We need to retry the lock. We may not be
655 * notified by the server if it just expired
656 * rather than being released.
658 ASSERTCMP(vnode->lock_state, ==, AFS_VNODE_LOCK_WAITING_FOR_CB);
659 afs_set_lock_state(vnode, AFS_VNODE_LOCK_SETTING);
660 fl->fl_u.afs.state = AFS_LOCK_PENDING;
664 case AFS_LOCK_GRANTED:
669 spin_unlock(&vnode->lock);
672 if (fl->fl_u.afs.state == AFS_LOCK_GRANTED)
673 goto vnode_is_locked;
674 ret = fl->fl_u.afs.state;
678 /* The VFS rejected the lock we just obtained, so we have to discard
679 * what we just got. We defer this to the lock manager work item to
682 _debug("vfs refused %d", ret);
685 spin_lock(&vnode->lock);
686 list_del_init(&fl->fl_u.afs.link);
687 afs_defer_unlock(vnode);
690 spin_unlock(&vnode->lock);
692 _leave(" = %d", ret);
697 * unlock on a file on the server
699 static int afs_do_unlk(struct file *file, struct file_lock *fl)
701 struct afs_vnode *vnode = AFS_FS_I(locks_inode(file));
704 _enter("{%llx:%llu},%u", vnode->fid.vid, vnode->fid.vnode, fl->fl_type);
706 trace_afs_flock_op(vnode, fl, afs_flock_op_unlock);
708 /* Flush all pending writes before doing anything with locks. */
711 ret = locks_lock_file_wait(file, fl);
712 _leave(" = %d [%u]", ret, vnode->lock_state);
717 * return information about a lock we currently hold, if indeed we hold one
719 static int afs_do_getlk(struct file *file, struct file_lock *fl)
721 struct afs_vnode *vnode = AFS_FS_I(locks_inode(file));
722 struct key *key = afs_file_key(file);
727 if (vnode->lock_state == AFS_VNODE_LOCK_DELETED)
730 fl->fl_type = F_UNLCK;
732 /* check local lock records first */
733 posix_test_lock(file, fl);
734 if (fl->fl_type == F_UNLCK) {
735 /* no local locks; consult the server */
736 ret = afs_fetch_status(vnode, key, false);
740 lock_count = READ_ONCE(vnode->status.lock_count);
741 if (lock_count != 0) {
743 fl->fl_type = F_RDLCK;
745 fl->fl_type = F_WRLCK;
747 fl->fl_end = OFFSET_MAX;
754 _leave(" = %d [%hd]", ret, fl->fl_type);
759 * manage POSIX locks on a file
761 int afs_lock(struct file *file, int cmd, struct file_lock *fl)
763 struct afs_vnode *vnode = AFS_FS_I(locks_inode(file));
764 enum afs_flock_operation op;
767 _enter("{%llx:%llu},%d,{t=%x,fl=%x,r=%Ld:%Ld}",
768 vnode->fid.vid, vnode->fid.vnode, cmd,
769 fl->fl_type, fl->fl_flags,
770 (long long) fl->fl_start, (long long) fl->fl_end);
772 /* AFS doesn't support mandatory locks */
773 if (__mandatory_lock(&vnode->vfs_inode) && fl->fl_type != F_UNLCK)
777 return afs_do_getlk(file, fl);
779 fl->fl_u.afs.debug_id = atomic_inc_return(&afs_file_lock_debug_id);
780 trace_afs_flock_op(vnode, fl, afs_flock_op_lock);
782 if (fl->fl_type == F_UNLCK)
783 ret = afs_do_unlk(file, fl);
785 ret = afs_do_setlk(file, fl);
788 case 0: op = afs_flock_op_return_ok; break;
789 case -EAGAIN: op = afs_flock_op_return_eagain; break;
790 case -EDEADLK: op = afs_flock_op_return_edeadlk; break;
791 default: op = afs_flock_op_return_error; break;
793 trace_afs_flock_op(vnode, fl, op);
798 * manage FLOCK locks on a file
800 int afs_flock(struct file *file, int cmd, struct file_lock *fl)
802 struct afs_vnode *vnode = AFS_FS_I(locks_inode(file));
803 enum afs_flock_operation op;
806 _enter("{%llx:%llu},%d,{t=%x,fl=%x}",
807 vnode->fid.vid, vnode->fid.vnode, cmd,
808 fl->fl_type, fl->fl_flags);
811 * No BSD flocks over NFS allowed.
812 * Note: we could try to fake a POSIX lock request here by
813 * using ((u32) filp | 0x80000000) or some such as the pid.
814 * Not sure whether that would be unique, though, or whether
815 * that would break in other places.
817 if (!(fl->fl_flags & FL_FLOCK))
820 fl->fl_u.afs.debug_id = atomic_inc_return(&afs_file_lock_debug_id);
821 trace_afs_flock_op(vnode, fl, afs_flock_op_flock);
823 /* we're simulating flock() locks using posix locks on the server */
824 if (fl->fl_type == F_UNLCK)
825 ret = afs_do_unlk(file, fl);
827 ret = afs_do_setlk(file, fl);
830 case 0: op = afs_flock_op_return_ok; break;
831 case -EAGAIN: op = afs_flock_op_return_eagain; break;
832 case -EDEADLK: op = afs_flock_op_return_edeadlk; break;
833 default: op = afs_flock_op_return_error; break;
835 trace_afs_flock_op(vnode, fl, op);
840 * the POSIX lock management core VFS code copies the lock record and adds the
841 * copy into its own list, so we need to add that copy to the vnode's lock
842 * queue in the same place as the original (which will be deleted shortly
845 static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl)
847 struct afs_vnode *vnode = AFS_FS_I(locks_inode(fl->fl_file));
851 new->fl_u.afs.debug_id = atomic_inc_return(&afs_file_lock_debug_id);
853 spin_lock(&vnode->lock);
854 trace_afs_flock_op(vnode, new, afs_flock_op_copy_lock);
855 list_add(&new->fl_u.afs.link, &fl->fl_u.afs.link);
856 spin_unlock(&vnode->lock);
860 * need to remove this lock from the vnode queue when it's removed from the
863 static void afs_fl_release_private(struct file_lock *fl)
865 struct afs_vnode *vnode = AFS_FS_I(locks_inode(fl->fl_file));
869 spin_lock(&vnode->lock);
871 trace_afs_flock_op(vnode, fl, afs_flock_op_release_lock);
872 list_del_init(&fl->fl_u.afs.link);
873 if (list_empty(&vnode->granted_locks))
874 afs_defer_unlock(vnode);
876 _debug("state %u for %p", vnode->lock_state, vnode);
877 spin_unlock(&vnode->lock);