1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 only,
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15 * General Public License version 2 for more details (a copy is included
16 * in the LICENSE file that accompanied this code).
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20 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
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23 * CA 95054 USA or visit www.sun.com if you need additional information or
29 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
30 * Use is subject to license terms.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * Implementation of cl_lock for OSC layer.
38 * Author: Nikita Danilov <nikita.danilov@sun.com>
41 #define DEBUG_SUBSYSTEM S_OSC
44 # include <libcfs/libcfs.h>
46 # include <liblustre.h>
48 /* fid_build_reg_res_name() */
49 #include <lustre_fid.h>
51 #include "osc_cl_internal.h"
57 #define _PAGEREF_MAGIC (-10000000)
59 /*****************************************************************************
65 static const struct cl_lock_operations osc_lock_ops;
66 static const struct cl_lock_operations osc_lock_lockless_ops;
67 static void osc_lock_to_lockless(const struct lu_env *env,
68 struct osc_lock *ols, int force);
69 static int osc_lock_has_pages(struct osc_lock *olck);
71 int osc_lock_is_lockless(const struct osc_lock *olck)
73 return (olck->ols_cl.cls_ops == &osc_lock_lockless_ops);
77 * Returns a weak pointer to the ldlm lock identified by a handle. Returned
78 * pointer cannot be dereferenced, as lock is not protected from concurrent
79 * reclaim. This function is a helper for osc_lock_invariant().
81 static struct ldlm_lock *osc_handle_ptr(struct lustre_handle *handle)
83 struct ldlm_lock *lock;
85 lock = ldlm_handle2lock(handle);
92 * Invariant that has to be true all of the time.
94 static int osc_lock_invariant(struct osc_lock *ols)
96 struct ldlm_lock *lock = osc_handle_ptr(&ols->ols_handle);
97 struct ldlm_lock *olock = ols->ols_lock;
98 int handle_used = lustre_handle_is_used(&ols->ols_handle);
101 ergo(osc_lock_is_lockless(ols),
102 ols->ols_locklessable && ols->ols_lock == NULL) ||
103 (ergo(olock != NULL, handle_used) &&
105 olock->l_handle.h_cookie == ols->ols_handle.cookie) &&
107 * Check that ->ols_handle and ->ols_lock are consistent, but
108 * take into account that they are set at the different time.
111 ergo(lock != NULL && olock != NULL, lock == olock) &&
112 ergo(lock == NULL, olock == NULL)) &&
113 ergo(ols->ols_state == OLS_CANCELLED,
114 olock == NULL && !handle_used) &&
116 * DLM lock is destroyed only after we have seen cancellation
119 ergo(olock != NULL && ols->ols_state < OLS_CANCELLED,
120 !olock->l_destroyed) &&
121 ergo(ols->ols_state == OLS_GRANTED,
123 olock->l_req_mode == olock->l_granted_mode &&
127 /*****************************************************************************
134 * Breaks a link between osc_lock and dlm_lock.
136 static void osc_lock_detach(const struct lu_env *env, struct osc_lock *olck)
138 struct ldlm_lock *dlmlock;
140 cfs_spin_lock(&osc_ast_guard);
141 dlmlock = olck->ols_lock;
142 if (dlmlock == NULL) {
143 cfs_spin_unlock(&osc_ast_guard);
147 olck->ols_lock = NULL;
148 /* wb(); --- for all who checks (ols->ols_lock != NULL) before
149 * call to osc_lock_detach() */
150 dlmlock->l_ast_data = NULL;
151 olck->ols_handle.cookie = 0ULL;
152 cfs_spin_unlock(&osc_ast_guard);
154 lock_res_and_lock(dlmlock);
155 if (dlmlock->l_granted_mode == dlmlock->l_req_mode) {
156 struct cl_object *obj = olck->ols_cl.cls_obj;
157 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
160 cl_object_attr_lock(obj);
161 /* Must get the value under the lock to avoid possible races. */
162 old_kms = cl2osc(obj)->oo_oinfo->loi_kms;
163 /* Update the kms. Need to loop all granted locks.
164 * Not a problem for the client */
165 attr->cat_kms = ldlm_extent_shift_kms(dlmlock, old_kms);
167 cl_object_attr_set(env, obj, attr, CAT_KMS);
168 cl_object_attr_unlock(obj);
170 unlock_res_and_lock(dlmlock);
172 /* release a reference taken in osc_lock_upcall0(). */
173 LASSERT(olck->ols_has_ref);
174 lu_ref_del(&dlmlock->l_reference, "osc_lock", olck);
175 LDLM_LOCK_RELEASE(dlmlock);
176 olck->ols_has_ref = 0;
179 static int osc_lock_unhold(struct osc_lock *ols)
185 result = osc_cancel_base(&ols->ols_handle,
186 ols->ols_einfo.ei_mode);
191 static int osc_lock_unuse(const struct lu_env *env,
192 const struct cl_lock_slice *slice)
194 struct osc_lock *ols = cl2osc_lock(slice);
196 LASSERT(ols->ols_state == OLS_GRANTED ||
197 ols->ols_state == OLS_UPCALL_RECEIVED);
198 LINVRNT(osc_lock_invariant(ols));
200 if (ols->ols_glimpse) {
201 LASSERT(ols->ols_hold == 0);
204 LASSERT(ols->ols_hold);
207 * Move lock into OLS_RELEASED state before calling osc_cancel_base()
208 * so that possible synchronous cancellation (that always happens
209 * e.g., for liblustre) sees that lock is released.
211 ols->ols_state = OLS_RELEASED;
212 return osc_lock_unhold(ols);
215 static void osc_lock_fini(const struct lu_env *env,
216 struct cl_lock_slice *slice)
218 struct osc_lock *ols = cl2osc_lock(slice);
220 LINVRNT(osc_lock_invariant(ols));
222 * ->ols_hold can still be true at this point if, for example, a
223 * thread that requested a lock was killed (and released a reference
224 * to the lock), before reply from a server was received. In this case
225 * lock is destroyed immediately after upcall.
227 osc_lock_unhold(ols);
228 LASSERT(ols->ols_lock == NULL);
229 LASSERT(cfs_atomic_read(&ols->ols_pageref) == 0 ||
230 cfs_atomic_read(&ols->ols_pageref) == _PAGEREF_MAGIC);
232 OBD_SLAB_FREE_PTR(ols, osc_lock_kmem);
235 void osc_lock_build_res(const struct lu_env *env, const struct osc_object *obj,
236 struct ldlm_res_id *resname)
238 const struct lu_fid *fid = lu_object_fid(&obj->oo_cl.co_lu);
241 * In the perfect world of the future, where ost servers talk
244 fid_build_reg_res_name(fid, resname);
247 * In reality, where ost server expects ->lsm_object_id and
248 * ->lsm_object_seq in rename.
250 osc_build_res_name(obj->oo_oinfo->loi_id, obj->oo_oinfo->loi_seq,
255 static void osc_lock_build_policy(const struct lu_env *env,
256 const struct cl_lock *lock,
257 ldlm_policy_data_t *policy)
259 const struct cl_lock_descr *d = &lock->cll_descr;
261 osc_index2policy(policy, d->cld_obj, d->cld_start, d->cld_end);
262 policy->l_extent.gid = d->cld_gid;
265 static int osc_enq2ldlm_flags(__u32 enqflags)
269 LASSERT((enqflags & ~CEF_MASK) == 0);
271 if (enqflags & CEF_NONBLOCK)
272 result |= LDLM_FL_BLOCK_NOWAIT;
273 if (enqflags & CEF_ASYNC)
274 result |= LDLM_FL_HAS_INTENT;
275 if (enqflags & CEF_DISCARD_DATA)
276 result |= LDLM_AST_DISCARD_DATA;
281 * Global spin-lock protecting consistency of ldlm_lock::l_ast_data
282 * pointers. Initialized in osc_init().
284 cfs_spinlock_t osc_ast_guard;
286 static struct osc_lock *osc_ast_data_get(struct ldlm_lock *dlm_lock)
288 struct osc_lock *olck;
290 lock_res_and_lock(dlm_lock);
291 cfs_spin_lock(&osc_ast_guard);
292 olck = dlm_lock->l_ast_data;
294 struct cl_lock *lock = olck->ols_cl.cls_lock;
296 * If osc_lock holds a reference on ldlm lock, return it even
297 * when cl_lock is in CLS_FREEING state. This way
299 * osc_ast_data_get(dlmlock) == NULL
301 * guarantees that all osc references on dlmlock were
302 * released. osc_dlm_blocking_ast0() relies on that.
304 if (lock->cll_state < CLS_FREEING || olck->ols_has_ref) {
305 cl_lock_get_trust(lock);
306 lu_ref_add_atomic(&lock->cll_reference,
307 "ast", cfs_current());
311 cfs_spin_unlock(&osc_ast_guard);
312 unlock_res_and_lock(dlm_lock);
316 static void osc_ast_data_put(const struct lu_env *env, struct osc_lock *olck)
318 struct cl_lock *lock;
320 lock = olck->ols_cl.cls_lock;
321 lu_ref_del(&lock->cll_reference, "ast", cfs_current());
322 cl_lock_put(env, lock);
326 * Updates object attributes from a lock value block (lvb) received together
327 * with the DLM lock reply from the server. Copy of osc_update_enqueue()
330 * This can be optimized to not update attributes when lock is a result of a
333 * Called under lock and resource spin-locks.
335 static void osc_lock_lvb_update(const struct lu_env *env, struct osc_lock *olck,
339 struct cl_object *obj;
340 struct lov_oinfo *oinfo;
341 struct cl_attr *attr;
346 if (!(olck->ols_flags & LDLM_FL_LVB_READY)) {
351 lvb = &olck->ols_lvb;
352 obj = olck->ols_cl.cls_obj;
353 oinfo = cl2osc(obj)->oo_oinfo;
354 attr = &osc_env_info(env)->oti_attr;
355 valid = CAT_BLOCKS | CAT_ATIME | CAT_CTIME | CAT_MTIME | CAT_SIZE;
356 cl_lvb2attr(attr, lvb);
358 cl_object_attr_lock(obj);
360 struct ldlm_lock *dlmlock;
363 dlmlock = olck->ols_lock;
364 LASSERT(dlmlock != NULL);
366 /* re-grab LVB from a dlm lock under DLM spin-locks. */
367 *lvb = *(struct ost_lvb *)dlmlock->l_lvb_data;
368 size = lvb->lvb_size;
369 /* Extend KMS up to the end of this lock and no further
370 * A lock on [x,y] means a KMS of up to y + 1 bytes! */
371 if (size > dlmlock->l_policy_data.l_extent.end)
372 size = dlmlock->l_policy_data.l_extent.end + 1;
373 if (size >= oinfo->loi_kms) {
374 LDLM_DEBUG(dlmlock, "lock acquired, setting rss="LPU64
375 ", kms="LPU64, lvb->lvb_size, size);
377 attr->cat_kms = size;
379 LDLM_DEBUG(dlmlock, "lock acquired, setting rss="
380 LPU64"; leaving kms="LPU64", end="LPU64,
381 lvb->lvb_size, oinfo->loi_kms,
382 dlmlock->l_policy_data.l_extent.end);
384 ldlm_lock_allow_match_locked(dlmlock);
385 } else if (rc == -ENAVAIL && olck->ols_glimpse) {
386 CDEBUG(D_INODE, "glimpsed, setting rss="LPU64"; leaving"
387 " kms="LPU64"\n", lvb->lvb_size, oinfo->loi_kms);
392 cl_object_attr_set(env, obj, attr, valid);
394 cl_object_attr_unlock(obj);
400 * Called when a lock is granted, from an upcall (when server returned a
401 * granted lock), or from completion AST, when server returned a blocked lock.
403 * Called under lock and resource spin-locks, that are released temporarily
406 static void osc_lock_granted(const struct lu_env *env, struct osc_lock *olck,
407 struct ldlm_lock *dlmlock, int rc)
409 struct ldlm_extent *ext;
410 struct cl_lock *lock;
411 struct cl_lock_descr *descr;
413 LASSERT(dlmlock->l_granted_mode == dlmlock->l_req_mode);
416 if (olck->ols_state < OLS_GRANTED) {
417 lock = olck->ols_cl.cls_lock;
418 ext = &dlmlock->l_policy_data.l_extent;
419 descr = &osc_env_info(env)->oti_descr;
420 descr->cld_obj = lock->cll_descr.cld_obj;
422 /* XXX check that ->l_granted_mode is valid. */
423 descr->cld_mode = osc_ldlm2cl_lock(dlmlock->l_granted_mode);
424 descr->cld_start = cl_index(descr->cld_obj, ext->start);
425 descr->cld_end = cl_index(descr->cld_obj, ext->end);
426 descr->cld_gid = ext->gid;
428 * tell upper layers the extent of the lock that was actually
431 olck->ols_state = OLS_GRANTED;
432 osc_lock_lvb_update(env, olck, rc);
434 /* release DLM spin-locks to allow cl_lock_{modify,signal}()
435 * to take a semaphore on a parent lock. This is safe, because
436 * spin-locks are needed to protect consistency of
437 * dlmlock->l_*_mode and LVB, and we have finished processing
439 unlock_res_and_lock(dlmlock);
440 cl_lock_modify(env, lock, descr);
441 cl_lock_signal(env, lock);
442 LINVRNT(osc_lock_invariant(olck));
443 lock_res_and_lock(dlmlock);
448 static void osc_lock_upcall0(const struct lu_env *env, struct osc_lock *olck)
451 struct ldlm_lock *dlmlock;
455 dlmlock = ldlm_handle2lock_long(&olck->ols_handle, 0);
456 LASSERT(dlmlock != NULL);
458 lock_res_and_lock(dlmlock);
459 cfs_spin_lock(&osc_ast_guard);
460 LASSERT(dlmlock->l_ast_data == olck);
461 LASSERT(olck->ols_lock == NULL);
462 olck->ols_lock = dlmlock;
463 cfs_spin_unlock(&osc_ast_guard);
466 * Lock might be not yet granted. In this case, completion ast
467 * (osc_ldlm_completion_ast()) comes later and finishes lock
470 if (dlmlock->l_granted_mode == dlmlock->l_req_mode)
471 osc_lock_granted(env, olck, dlmlock, 0);
472 unlock_res_and_lock(dlmlock);
475 * osc_enqueue_interpret() decrefs asynchronous locks, counter
478 ldlm_lock_addref(&olck->ols_handle, olck->ols_einfo.ei_mode);
481 /* lock reference taken by ldlm_handle2lock_long() is owned by
482 * osc_lock and released in osc_lock_detach() */
483 lu_ref_add(&dlmlock->l_reference, "osc_lock", olck);
484 olck->ols_has_ref = 1;
488 * Lock upcall function that is executed either when a reply to ENQUEUE rpc is
489 * received from a server, or after osc_enqueue_base() matched a local DLM
492 static int osc_lock_upcall(void *cookie, int errcode)
494 struct osc_lock *olck = cookie;
495 struct cl_lock_slice *slice = &olck->ols_cl;
496 struct cl_lock *lock = slice->cls_lock;
498 struct cl_env_nest nest;
501 env = cl_env_nested_get(&nest);
505 cl_lock_mutex_get(env, lock);
507 LASSERT(lock->cll_state >= CLS_QUEUING);
508 if (olck->ols_state == OLS_ENQUEUED) {
509 olck->ols_state = OLS_UPCALL_RECEIVED;
510 rc = ldlm_error2errno(errcode);
511 } else if (olck->ols_state == OLS_CANCELLED) {
514 CERROR("Impossible state: %d\n", olck->ols_state);
518 struct ldlm_lock *dlmlock;
520 dlmlock = ldlm_handle2lock(&olck->ols_handle);
521 if (dlmlock != NULL) {
522 lock_res_and_lock(dlmlock);
523 cfs_spin_lock(&osc_ast_guard);
524 LASSERT(olck->ols_lock == NULL);
525 dlmlock->l_ast_data = NULL;
526 olck->ols_handle.cookie = 0ULL;
527 cfs_spin_unlock(&osc_ast_guard);
528 unlock_res_and_lock(dlmlock);
529 LDLM_LOCK_PUT(dlmlock);
532 if (olck->ols_glimpse)
533 olck->ols_glimpse = 0;
534 osc_lock_upcall0(env, olck);
537 /* Error handling, some errors are tolerable. */
538 if (olck->ols_locklessable && rc == -EUSERS) {
539 /* This is a tolerable error, turn this lock into
542 osc_object_set_contended(cl2osc(slice->cls_obj));
543 LASSERT(slice->cls_ops == &osc_lock_ops);
545 /* Change this lock to ldlmlock-less lock. */
546 osc_lock_to_lockless(env, olck, 1);
547 olck->ols_state = OLS_GRANTED;
549 } else if (olck->ols_glimpse && rc == -ENAVAIL) {
550 osc_lock_lvb_update(env, olck, rc);
551 cl_lock_delete(env, lock);
552 /* Hide the error. */
557 /* on error, lock was signaled by cl_lock_error() */
558 cl_lock_signal(env, lock);
560 cl_lock_error(env, lock, rc);
562 cl_lock_mutex_put(env, lock);
564 /* release cookie reference, acquired by osc_lock_enqueue() */
565 lu_ref_del(&lock->cll_reference, "upcall", lock);
566 cl_lock_put(env, lock);
567 cl_env_nested_put(&nest, env);
569 /* should never happen, similar to osc_ldlm_blocking_ast(). */
575 * Core of osc_dlm_blocking_ast() logic.
577 static void osc_lock_blocking(const struct lu_env *env,
578 struct ldlm_lock *dlmlock,
579 struct osc_lock *olck, int blocking)
581 struct cl_lock *lock = olck->ols_cl.cls_lock;
583 LASSERT(olck->ols_lock == dlmlock);
584 CLASSERT(OLS_BLOCKED < OLS_CANCELLED);
585 LASSERT(!osc_lock_is_lockless(olck));
588 * Lock might be still addref-ed here, if e.g., blocking ast
589 * is sent for a failed lock.
591 osc_lock_unhold(olck);
593 if (blocking && olck->ols_state < OLS_BLOCKED)
595 * Move osc_lock into OLS_BLOCKED before canceling the lock,
596 * because it recursively re-enters osc_lock_blocking(), with
597 * the state set to OLS_CANCELLED.
599 olck->ols_state = OLS_BLOCKED;
601 * cancel and destroy lock at least once no matter how blocking ast is
602 * entered (see comment above osc_ldlm_blocking_ast() for use
603 * cases). cl_lock_cancel() and cl_lock_delete() are idempotent.
605 cl_lock_cancel(env, lock);
606 cl_lock_delete(env, lock);
610 * Helper for osc_dlm_blocking_ast() handling discrepancies between cl_lock
611 * and ldlm_lock caches.
613 static int osc_dlm_blocking_ast0(const struct lu_env *env,
614 struct ldlm_lock *dlmlock,
615 void *data, int flag)
617 struct osc_lock *olck;
618 struct cl_lock *lock;
622 LASSERT(flag == LDLM_CB_BLOCKING || flag == LDLM_CB_CANCELING);
625 olck = osc_ast_data_get(dlmlock);
627 lock = olck->ols_cl.cls_lock;
628 cl_lock_mutex_get(env, lock);
629 LINVRNT(osc_lock_invariant(olck));
630 if (olck->ols_ast_wait) {
631 /* wake up osc_lock_use() */
632 cl_lock_signal(env, lock);
633 olck->ols_ast_wait = 0;
636 * Lock might have been canceled while this thread was
637 * sleeping for lock mutex, but olck is pinned in memory.
639 if (olck == dlmlock->l_ast_data) {
641 * NOTE: DLM sends blocking AST's for failed locks
642 * (that are still in pre-OLS_GRANTED state)
643 * too, and they have to be canceled otherwise
644 * DLM lock is never destroyed and stuck in
647 * Alternatively, ldlm_cli_cancel() can be
648 * called here directly for osc_locks with
649 * ols_state < OLS_GRANTED to maintain an
650 * invariant that ->clo_cancel() is only called
651 * for locks that were granted.
653 LASSERT(data == olck);
654 osc_lock_blocking(env, dlmlock,
655 olck, flag == LDLM_CB_BLOCKING);
658 cl_lock_mutex_put(env, lock);
659 osc_ast_data_put(env, olck);
662 * DLM lock exists, but there is no cl_lock attached to it.
663 * This is a `normal' race. cl_object and its cl_lock's can be
664 * removed by memory pressure, together with all pages.
666 cancel = (flag == LDLM_CB_BLOCKING);
669 struct lustre_handle *lockh;
671 lockh = &osc_env_info(env)->oti_handle;
672 ldlm_lock2handle(dlmlock, lockh);
673 result = ldlm_cli_cancel(lockh);
680 * Blocking ast invoked by ldlm when dlm lock is either blocking progress of
681 * some other lock, or is canceled. This function is installed as a
682 * ldlm_lock::l_blocking_ast() for client extent locks.
684 * Control flow is tricky, because ldlm uses the same call-back
685 * (ldlm_lock::l_blocking_ast()) for both blocking and cancellation ast's.
687 * \param dlmlock lock for which ast occurred.
689 * \param new description of a conflicting lock in case of blocking ast.
691 * \param data value of dlmlock->l_ast_data
693 * \param flag LDLM_CB_BLOCKING or LDLM_CB_CANCELING. Used to distinguish
694 * cancellation and blocking ast's.
696 * Possible use cases:
698 * - ldlm calls dlmlock->l_blocking_ast(..., LDLM_CB_CANCELING) to cancel
699 * lock due to lock lru pressure, or explicit user request to purge
702 * - ldlm calls dlmlock->l_blocking_ast(..., LDLM_CB_BLOCKING) to notify
703 * us that dlmlock conflicts with another lock that some client is
704 * enqueing. Lock is canceled.
706 * - cl_lock_cancel() is called. osc_lock_cancel() calls
707 * ldlm_cli_cancel() that calls
709 * dlmlock->l_blocking_ast(..., LDLM_CB_CANCELING)
711 * recursively entering osc_ldlm_blocking_ast().
713 * - client cancels lock voluntary (e.g., as a part of early cancellation):
716 * osc_lock_cancel()->
717 * ldlm_cli_cancel()->
718 * dlmlock->l_blocking_ast(..., LDLM_CB_CANCELING)
721 static int osc_ldlm_blocking_ast(struct ldlm_lock *dlmlock,
722 struct ldlm_lock_desc *new, void *data,
726 struct cl_env_nest nest;
730 * This can be called in the context of outer IO, e.g.,
733 * ->osc_enqueue_base()->...
734 * ->ldlm_prep_elc_req()->...
735 * ->ldlm_cancel_callback()->...
736 * ->osc_ldlm_blocking_ast()
738 * new environment has to be created to not corrupt outer context.
740 env = cl_env_nested_get(&nest);
742 result = osc_dlm_blocking_ast0(env, dlmlock, data, flag);
743 cl_env_nested_put(&nest, env);
745 result = PTR_ERR(env);
747 * XXX This should never happen, as cl_lock is
748 * stuck. Pre-allocated environment a la vvp_inode_fini_env
754 if (result == -ENODATA)
757 CERROR("BAST failed: %d\n", result);
762 static int osc_ldlm_completion_ast(struct ldlm_lock *dlmlock,
763 int flags, void *data)
765 struct cl_env_nest nest;
767 struct osc_lock *olck;
768 struct cl_lock *lock;
772 /* first, do dlm part of the work */
773 dlmrc = ldlm_completion_ast_async(dlmlock, flags, data);
774 /* then, notify cl_lock */
775 env = cl_env_nested_get(&nest);
777 olck = osc_ast_data_get(dlmlock);
779 lock = olck->ols_cl.cls_lock;
780 cl_lock_mutex_get(env, lock);
782 * ldlm_handle_cp_callback() copied LVB from request
783 * to lock->l_lvb_data, store it in osc_lock.
785 LASSERT(dlmlock->l_lvb_data != NULL);
786 lock_res_and_lock(dlmlock);
787 olck->ols_lvb = *(struct ost_lvb *)dlmlock->l_lvb_data;
788 if (olck->ols_lock == NULL) {
790 * upcall (osc_lock_upcall()) hasn't yet been
791 * called. Do nothing now, upcall will bind
792 * olck to dlmlock and signal the waiters.
794 * This maintains an invariant that osc_lock
795 * and ldlm_lock are always bound when
796 * osc_lock is in OLS_GRANTED state.
798 } else if (dlmlock->l_granted_mode ==
799 dlmlock->l_req_mode) {
800 osc_lock_granted(env, olck, dlmlock, dlmrc);
802 unlock_res_and_lock(dlmlock);
805 CL_LOCK_DEBUG(D_ERROR, env, lock,
806 "dlmlock returned %d\n", dlmrc);
807 cl_lock_error(env, lock, dlmrc);
809 cl_lock_mutex_put(env, lock);
810 osc_ast_data_put(env, olck);
813 result = -ELDLM_NO_LOCK_DATA;
814 cl_env_nested_put(&nest, env);
816 result = PTR_ERR(env);
817 return dlmrc ?: result;
820 static int osc_ldlm_glimpse_ast(struct ldlm_lock *dlmlock, void *data)
822 struct ptlrpc_request *req = data;
823 struct osc_lock *olck;
824 struct cl_lock *lock;
825 struct cl_object *obj;
826 struct cl_env_nest nest;
829 struct req_capsule *cap;
832 LASSERT(lustre_msg_get_opc(req->rq_reqmsg) == LDLM_GL_CALLBACK);
834 env = cl_env_nested_get(&nest);
837 * osc_ast_data_get() has to go after environment is
838 * allocated, because osc_ast_data() acquires a
839 * reference to a lock, and it can only be released in
842 olck = osc_ast_data_get(dlmlock);
844 lock = olck->ols_cl.cls_lock;
845 cl_lock_mutex_get(env, lock);
847 req_capsule_extend(cap, &RQF_LDLM_GL_CALLBACK);
848 req_capsule_set_size(cap, &RMF_DLM_LVB, RCL_SERVER,
850 result = req_capsule_server_pack(cap);
852 lvb = req_capsule_server_get(cap, &RMF_DLM_LVB);
853 obj = lock->cll_descr.cld_obj;
854 result = cl_object_glimpse(env, obj, lvb);
856 cl_lock_mutex_put(env, lock);
857 osc_ast_data_put(env, olck);
860 * These errors are normal races, so we don't want to
861 * fill the console with messages by calling
864 lustre_pack_reply(req, 1, NULL, NULL);
865 result = -ELDLM_NO_LOCK_DATA;
867 cl_env_nested_put(&nest, env);
869 result = PTR_ERR(env);
870 req->rq_status = result;
874 static unsigned long osc_lock_weigh(const struct lu_env *env,
875 const struct cl_lock_slice *slice)
878 * don't need to grab coh_page_guard since we don't care the exact #
881 return cl_object_header(slice->cls_obj)->coh_pages;
885 * Get the weight of dlm lock for early cancellation.
887 * XXX: it should return the pages covered by this \a dlmlock.
889 static unsigned long osc_ldlm_weigh_ast(struct ldlm_lock *dlmlock)
891 struct cl_env_nest nest;
893 struct osc_lock *lock;
895 unsigned long weight;
900 * osc_ldlm_weigh_ast has a complex context since it might be called
901 * because of lock canceling, or from user's input. We have to make
902 * a new environment for it. Probably it is implementation safe to use
903 * the upper context because cl_lock_put don't modify environment
904 * variables. But in case of ..
906 env = cl_env_nested_get(&nest);
908 /* Mostly because lack of memory, tend to eliminate this lock*/
911 LASSERT(dlmlock->l_resource->lr_type == LDLM_EXTENT);
912 lock = osc_ast_data_get(dlmlock);
914 /* cl_lock was destroyed because of memory pressure.
915 * It is much reasonable to assign this type of lock
918 GOTO(out, weight = 0);
921 cll = lock->ols_cl.cls_lock;
922 cl_lock_mutex_get(env, cll);
923 weight = cl_lock_weigh(env, cll);
924 cl_lock_mutex_put(env, cll);
925 osc_ast_data_put(env, lock);
929 cl_env_nested_put(&nest, env);
933 static void osc_lock_build_einfo(const struct lu_env *env,
934 const struct cl_lock *clock,
935 struct osc_lock *lock,
936 struct ldlm_enqueue_info *einfo)
938 enum cl_lock_mode mode;
940 mode = clock->cll_descr.cld_mode;
941 if (mode == CLM_PHANTOM)
943 * For now, enqueue all glimpse locks in read mode. In the
944 * future, client might choose to enqueue LCK_PW lock for
945 * glimpse on a file opened for write.
949 einfo->ei_type = LDLM_EXTENT;
950 einfo->ei_mode = osc_cl_lock2ldlm(mode);
951 einfo->ei_cb_bl = osc_ldlm_blocking_ast;
952 einfo->ei_cb_cp = osc_ldlm_completion_ast;
953 einfo->ei_cb_gl = osc_ldlm_glimpse_ast;
954 einfo->ei_cb_wg = osc_ldlm_weigh_ast;
955 einfo->ei_cbdata = lock; /* value to be put into ->l_ast_data */
959 * Determine if the lock should be converted into a lockless lock.
962 * - if the lock has an explicite requirment for a non-lockless lock;
963 * - if the io lock request type ci_lockreq;
964 * - send the enqueue rpc to ost to make the further decision;
965 * - special treat to truncate lockless lock
967 * Additional policy can be implemented here, e.g., never do lockless-io
970 static void osc_lock_to_lockless(const struct lu_env *env,
971 struct osc_lock *ols, int force)
973 struct cl_lock_slice *slice = &ols->ols_cl;
974 struct cl_lock *lock = slice->cls_lock;
976 LASSERT(ols->ols_state == OLS_NEW ||
977 ols->ols_state == OLS_UPCALL_RECEIVED);
980 ols->ols_locklessable = 1;
981 LASSERT(cl_lock_is_mutexed(lock));
982 slice->cls_ops = &osc_lock_lockless_ops;
984 struct osc_io *oio = osc_env_io(env);
985 struct cl_io *io = oio->oi_cl.cis_io;
986 struct cl_object *obj = slice->cls_obj;
987 struct osc_object *oob = cl2osc(obj);
988 const struct osc_device *osd = lu2osc_dev(obj->co_lu.lo_dev);
989 struct obd_connect_data *ocd;
991 LASSERT(io->ci_lockreq == CILR_MANDATORY ||
992 io->ci_lockreq == CILR_MAYBE ||
993 io->ci_lockreq == CILR_NEVER);
995 ocd = &class_exp2cliimp(osc_export(oob))->imp_connect_data;
996 ols->ols_locklessable = (io->ci_type != CIT_SETATTR) &&
997 (io->ci_lockreq == CILR_MAYBE) &&
998 (ocd->ocd_connect_flags & OBD_CONNECT_SRVLOCK);
999 if (io->ci_lockreq == CILR_NEVER ||
1001 (ols->ols_locklessable && osc_object_is_contended(oob)) ||
1002 /* lockless truncate */
1003 (cl_io_is_trunc(io) &&
1004 (ocd->ocd_connect_flags & OBD_CONNECT_TRUNCLOCK) &&
1005 osd->od_lockless_truncate)) {
1006 ols->ols_locklessable = 1;
1007 slice->cls_ops = &osc_lock_lockless_ops;
1010 LASSERT(ergo(ols->ols_glimpse, !osc_lock_is_lockless(ols)));
1013 static int osc_lock_compatible(const struct osc_lock *qing,
1014 const struct osc_lock *qed)
1016 enum cl_lock_mode qing_mode;
1017 enum cl_lock_mode qed_mode;
1019 qing_mode = qing->ols_cl.cls_lock->cll_descr.cld_mode;
1020 if (qed->ols_glimpse &&
1021 (qed->ols_state >= OLS_UPCALL_RECEIVED || qing_mode == CLM_READ))
1024 qed_mode = qed->ols_cl.cls_lock->cll_descr.cld_mode;
1025 return ((qing_mode == CLM_READ) && (qed_mode == CLM_READ));
1029 * Cancel all conflicting locks and wait for them to be destroyed.
1031 * This function is used for two purposes:
1033 * - early cancel all conflicting locks before starting IO, and
1035 * - guarantee that pages added to the page cache by lockless IO are never
1036 * covered by locks other than lockless IO lock, and, hence, are not
1037 * visible to other threads.
1039 static int osc_lock_enqueue_wait(const struct lu_env *env,
1040 const struct osc_lock *olck)
1042 struct cl_lock *lock = olck->ols_cl.cls_lock;
1043 struct cl_lock_descr *descr = &lock->cll_descr;
1044 struct cl_object_header *hdr = cl_object_header(descr->cld_obj);
1045 struct cl_lock *scan;
1046 struct cl_lock *conflict= NULL;
1047 int lockless = osc_lock_is_lockless(olck);
1051 LASSERT(cl_lock_is_mutexed(lock));
1052 LASSERT(lock->cll_state == CLS_QUEUING);
1054 /* make it enqueue anyway for glimpse lock, because we actually
1055 * don't need to cancel any conflicting locks. */
1056 if (olck->ols_glimpse)
1059 cfs_spin_lock(&hdr->coh_lock_guard);
1060 cfs_list_for_each_entry(scan, &hdr->coh_locks, cll_linkage) {
1061 struct cl_lock_descr *cld = &scan->cll_descr;
1062 const struct osc_lock *scan_ols;
1067 if (scan->cll_state < CLS_QUEUING ||
1068 scan->cll_state == CLS_FREEING ||
1069 cld->cld_start > descr->cld_end ||
1070 cld->cld_end < descr->cld_start)
1073 /* overlapped and living locks. */
1075 /* We're not supposed to give up group lock. */
1076 if (scan->cll_descr.cld_mode == CLM_GROUP) {
1077 LASSERT(descr->cld_mode != CLM_GROUP ||
1078 descr->cld_gid != scan->cll_descr.cld_gid);
1082 scan_ols = osc_lock_at(scan);
1084 /* We need to cancel the compatible locks if we're enqueuing
1085 * a lockless lock, for example:
1086 * imagine that client has PR lock on [0, 1000], and thread T0
1087 * is doing lockless IO in [500, 1500] region. Concurrent
1088 * thread T1 can see lockless data in [500, 1000], which is
1089 * wrong, because these data are possibly stale. */
1090 if (!lockless && osc_lock_compatible(olck, scan_ols))
1093 /* Now @scan is conflicting with @lock, this means current
1094 * thread have to sleep for @scan being destroyed. */
1095 if (scan_ols->ols_owner == osc_env_io(env)) {
1096 CERROR("DEADLOCK POSSIBLE!\n");
1097 CL_LOCK_DEBUG(D_ERROR, env, scan, "queued.\n");
1098 CL_LOCK_DEBUG(D_ERROR, env, lock, "queuing.\n");
1099 libcfs_debug_dumpstack(NULL);
1101 cl_lock_get_trust(scan);
1105 cfs_spin_unlock(&hdr->coh_lock_guard);
1108 if (lock->cll_descr.cld_mode == CLM_GROUP) {
1109 /* we want a group lock but a previous lock request
1110 * conflicts, we do not wait but return 0 so the
1111 * request is send to the server
1113 CDEBUG(D_DLMTRACE, "group lock %p is conflicted "
1114 "with %p, no wait, send to server\n",
1116 cl_lock_put(env, conflict);
1119 CDEBUG(D_DLMTRACE, "lock %p is conflicted with %p, "
1122 LASSERT(lock->cll_conflict == NULL);
1123 lu_ref_add(&conflict->cll_reference, "cancel-wait",
1125 lock->cll_conflict = conflict;
1133 * Implementation of cl_lock_operations::clo_enqueue() method for osc
1134 * layer. This initiates ldlm enqueue:
1136 * - cancels conflicting locks early (osc_lock_enqueue_wait());
1138 * - calls osc_enqueue_base() to do actual enqueue.
1140 * osc_enqueue_base() is supplied with an upcall function that is executed
1141 * when lock is received either after a local cached ldlm lock is matched, or
1142 * when a reply from the server is received.
1144 * This function does not wait for the network communication to complete.
1146 static int osc_lock_enqueue(const struct lu_env *env,
1147 const struct cl_lock_slice *slice,
1148 struct cl_io *unused, __u32 enqflags)
1150 struct osc_lock *ols = cl2osc_lock(slice);
1151 struct cl_lock *lock = ols->ols_cl.cls_lock;
1155 LASSERT(cl_lock_is_mutexed(lock));
1156 LASSERT(lock->cll_state == CLS_QUEUING);
1157 LASSERT(ols->ols_state == OLS_NEW);
1159 ols->ols_flags = osc_enq2ldlm_flags(enqflags);
1160 if (ols->ols_flags & LDLM_FL_HAS_INTENT)
1161 ols->ols_glimpse = 1;
1162 if (!osc_lock_is_lockless(ols) && !(enqflags & CEF_MUST))
1163 /* try to convert this lock to a lockless lock */
1164 osc_lock_to_lockless(env, ols, (enqflags & CEF_NEVER));
1166 result = osc_lock_enqueue_wait(env, ols);
1168 if (!osc_lock_is_lockless(ols)) {
1169 struct osc_object *obj = cl2osc(slice->cls_obj);
1170 struct osc_thread_info *info = osc_env_info(env);
1171 struct ldlm_res_id *resname = &info->oti_resname;
1172 ldlm_policy_data_t *policy = &info->oti_policy;
1173 struct ldlm_enqueue_info *einfo = &ols->ols_einfo;
1175 if (ols->ols_locklessable)
1176 ols->ols_flags |= LDLM_FL_DENY_ON_CONTENTION;
1178 /* a reference for lock, passed as an upcall cookie */
1180 lu_ref_add(&lock->cll_reference, "upcall", lock);
1181 ols->ols_state = OLS_ENQUEUED;
1184 * XXX: this is possible blocking point as
1185 * ldlm_lock_match(LDLM_FL_LVB_READY) waits for
1188 osc_lock_build_res(env, obj, resname);
1189 osc_lock_build_policy(env, lock, policy);
1190 result = osc_enqueue_base(osc_export(obj), resname,
1191 &ols->ols_flags, policy,
1193 obj->oo_oinfo->loi_kms_valid,
1195 ols, einfo, &ols->ols_handle,
1198 lu_ref_del(&lock->cll_reference,
1200 cl_lock_put(env, lock);
1203 ols->ols_state = OLS_GRANTED;
1204 ols->ols_owner = osc_env_io(env);
1207 LASSERT(ergo(ols->ols_glimpse, !osc_lock_is_lockless(ols)));
1211 static int osc_lock_wait(const struct lu_env *env,
1212 const struct cl_lock_slice *slice)
1214 struct osc_lock *olck = cl2osc_lock(slice);
1215 struct cl_lock *lock = olck->ols_cl.cls_lock;
1217 LINVRNT(osc_lock_invariant(olck));
1218 if (olck->ols_glimpse && olck->ols_state >= OLS_UPCALL_RECEIVED)
1221 LASSERT(equi(olck->ols_state >= OLS_UPCALL_RECEIVED &&
1222 lock->cll_error == 0, olck->ols_lock != NULL));
1224 return lock->cll_error ?: olck->ols_state >= OLS_GRANTED ? 0 : CLO_WAIT;
1228 * An implementation of cl_lock_operations::clo_use() method that pins cached
1231 static int osc_lock_use(const struct lu_env *env,
1232 const struct cl_lock_slice *slice)
1234 struct osc_lock *olck = cl2osc_lock(slice);
1237 LASSERT(!olck->ols_hold);
1240 * Atomically check for LDLM_FL_CBPENDING and addref a lock if this
1241 * flag is not set. This protects us from a concurrent blocking ast.
1243 rc = ldlm_lock_addref_try(&olck->ols_handle, olck->ols_einfo.ei_mode);
1246 olck->ols_state = OLS_GRANTED;
1248 struct cl_lock *lock;
1251 * Lock is being cancelled somewhere within
1252 * ldlm_handle_bl_callback(): LDLM_FL_CBPENDING is already
1253 * set, but osc_ldlm_blocking_ast() hasn't yet acquired
1256 lock = slice->cls_lock;
1257 LASSERT(lock->cll_state == CLS_INTRANSIT);
1258 LASSERT(lock->cll_users > 0);
1259 /* set a flag for osc_dlm_blocking_ast0() to signal the
1261 olck->ols_ast_wait = 1;
1267 static int osc_lock_flush(struct osc_lock *ols, int discard)
1269 struct cl_lock *lock = ols->ols_cl.cls_lock;
1270 struct cl_env_nest nest;
1274 env = cl_env_nested_get(&nest);
1276 result = cl_lock_page_out(env, lock, discard);
1277 cl_env_nested_put(&nest, env);
1279 result = PTR_ERR(env);
1282 LINVRNT(!osc_lock_has_pages(ols));
1288 * Implements cl_lock_operations::clo_cancel() method for osc layer. This is
1289 * called (as part of cl_lock_cancel()) when lock is canceled either voluntary
1290 * (LRU pressure, early cancellation, umount, etc.) or due to the conflict
1291 * with some other lock some where in the cluster. This function does the
1294 * - invalidates all pages protected by this lock (after sending dirty
1295 * ones to the server, as necessary);
1297 * - decref's underlying ldlm lock;
1299 * - cancels ldlm lock (ldlm_cli_cancel()).
1301 static void osc_lock_cancel(const struct lu_env *env,
1302 const struct cl_lock_slice *slice)
1304 struct cl_lock *lock = slice->cls_lock;
1305 struct osc_lock *olck = cl2osc_lock(slice);
1306 struct ldlm_lock *dlmlock = olck->ols_lock;
1310 LASSERT(cl_lock_is_mutexed(lock));
1311 LINVRNT(osc_lock_invariant(olck));
1313 if (dlmlock != NULL) {
1316 discard = dlmlock->l_flags & LDLM_FL_DISCARD_DATA;
1317 result = osc_lock_flush(olck, discard);
1318 osc_lock_unhold(olck);
1320 lock_res_and_lock(dlmlock);
1321 /* Now that we're the only user of dlm read/write reference,
1322 * mostly the ->l_readers + ->l_writers should be zero.
1323 * However, there is a corner case.
1324 * See bug 18829 for details.*/
1325 do_cancel = (dlmlock->l_readers == 0 &&
1326 dlmlock->l_writers == 0);
1327 dlmlock->l_flags |= LDLM_FL_CBPENDING;
1328 unlock_res_and_lock(dlmlock);
1330 result = ldlm_cli_cancel(&olck->ols_handle);
1332 CL_LOCK_DEBUG(D_ERROR, env, lock,
1333 "lock %p cancel failure with error(%d)\n",
1336 olck->ols_state = OLS_CANCELLED;
1337 osc_lock_detach(env, olck);
1340 void cl_lock_page_list_fixup(const struct lu_env *env,
1341 struct cl_io *io, struct cl_lock *lock,
1342 struct cl_page_list *queue);
1344 #ifdef INVARIANT_CHECK
1346 * Returns true iff there are pages under \a olck not protected by other
1349 static int osc_lock_has_pages(struct osc_lock *olck)
1351 struct cl_lock *lock;
1352 struct cl_lock_descr *descr;
1353 struct cl_object *obj;
1354 struct osc_object *oob;
1355 struct cl_page_list *plist;
1356 struct cl_page *page;
1357 struct cl_env_nest nest;
1362 env = cl_env_nested_get(&nest);
1364 obj = olck->ols_cl.cls_obj;
1366 io = &oob->oo_debug_io;
1367 lock = olck->ols_cl.cls_lock;
1368 descr = &lock->cll_descr;
1369 plist = &osc_env_info(env)->oti_plist;
1370 cl_page_list_init(plist);
1372 cfs_mutex_lock(&oob->oo_debug_mutex);
1374 io->ci_obj = cl_object_top(obj);
1375 cl_io_init(env, io, CIT_MISC, io->ci_obj);
1376 cl_page_gang_lookup(env, obj, io,
1377 descr->cld_start, descr->cld_end, plist, 0,
1379 cl_lock_page_list_fixup(env, io, lock, plist);
1380 if (plist->pl_nr > 0) {
1381 CL_LOCK_DEBUG(D_ERROR, env, lock, "still has pages\n");
1382 cl_page_list_for_each(page, plist)
1383 CL_PAGE_DEBUG(D_ERROR, env, page, "\n");
1385 result = plist->pl_nr > 0;
1386 cl_page_list_disown(env, io, plist);
1387 cl_page_list_fini(env, plist);
1388 cl_io_fini(env, io);
1389 cfs_mutex_unlock(&oob->oo_debug_mutex);
1390 cl_env_nested_put(&nest, env);
1396 static int osc_lock_has_pages(struct osc_lock *olck)
1400 #endif /* INVARIANT_CHECK */
1402 static void osc_lock_delete(const struct lu_env *env,
1403 const struct cl_lock_slice *slice)
1405 struct osc_lock *olck;
1407 olck = cl2osc_lock(slice);
1408 if (olck->ols_glimpse) {
1409 LASSERT(!olck->ols_hold);
1410 LASSERT(!olck->ols_lock);
1414 LINVRNT(osc_lock_invariant(olck));
1415 LINVRNT(!osc_lock_has_pages(olck));
1417 osc_lock_unhold(olck);
1418 osc_lock_detach(env, olck);
1422 * Implements cl_lock_operations::clo_state() method for osc layer.
1424 * Maintains osc_lock::ols_owner field.
1426 * This assumes that lock always enters CLS_HELD (from some other state) in
1427 * the same IO context as one that requested the lock. This should not be a
1428 * problem, because context is by definition shared by all activity pertaining
1429 * to the same high-level IO.
1431 static void osc_lock_state(const struct lu_env *env,
1432 const struct cl_lock_slice *slice,
1433 enum cl_lock_state state)
1435 struct osc_lock *lock = cl2osc_lock(slice);
1438 * XXX multiple io contexts can use the lock at the same time.
1440 LINVRNT(osc_lock_invariant(lock));
1441 if (state == CLS_HELD && slice->cls_lock->cll_state != CLS_HELD) {
1442 struct osc_io *oio = osc_env_io(env);
1444 LASSERT(lock->ols_owner == NULL);
1445 lock->ols_owner = oio;
1446 } else if (state != CLS_HELD)
1447 lock->ols_owner = NULL;
1450 static int osc_lock_print(const struct lu_env *env, void *cookie,
1451 lu_printer_t p, const struct cl_lock_slice *slice)
1453 struct osc_lock *lock = cl2osc_lock(slice);
1456 * XXX print ldlm lock and einfo properly.
1458 (*p)(env, cookie, "%p %08x "LPX64" %d %p ",
1459 lock->ols_lock, lock->ols_flags, lock->ols_handle.cookie,
1460 lock->ols_state, lock->ols_owner);
1461 osc_lvb_print(env, cookie, p, &lock->ols_lvb);
1465 static int osc_lock_fits_into(const struct lu_env *env,
1466 const struct cl_lock_slice *slice,
1467 const struct cl_lock_descr *need,
1468 const struct cl_io *io)
1470 struct osc_lock *ols = cl2osc_lock(slice);
1472 if (need->cld_enq_flags & CEF_NEVER)
1475 if (need->cld_mode == CLM_PHANTOM) {
1477 * Note: the QUEUED lock can't be matched here, otherwise
1478 * it might cause the deadlocks.
1480 * P1: enqueued read lock, create sublock1
1481 * P2: enqueued write lock, create sublock2(conflicted
1483 * P1: Grant read lock.
1484 * P1: enqueued glimpse lock(with holding sublock1_read),
1485 * matched with sublock2, waiting sublock2 to be granted.
1486 * But sublock2 can not be granted, because P1
1487 * will not release sublock1. Bang!
1489 if (ols->ols_state < OLS_GRANTED ||
1490 ols->ols_state > OLS_RELEASED)
1492 } else if (need->cld_enq_flags & CEF_MUST) {
1494 * If the lock hasn't ever enqueued, it can't be matched
1495 * because enqueue process brings in many information
1496 * which can be used to determine things such as lockless,
1499 if (ols->ols_state < OLS_UPCALL_RECEIVED &&
1500 ols->ols_locklessable)
1506 static const struct cl_lock_operations osc_lock_ops = {
1507 .clo_fini = osc_lock_fini,
1508 .clo_enqueue = osc_lock_enqueue,
1509 .clo_wait = osc_lock_wait,
1510 .clo_unuse = osc_lock_unuse,
1511 .clo_use = osc_lock_use,
1512 .clo_delete = osc_lock_delete,
1513 .clo_state = osc_lock_state,
1514 .clo_cancel = osc_lock_cancel,
1515 .clo_weigh = osc_lock_weigh,
1516 .clo_print = osc_lock_print,
1517 .clo_fits_into = osc_lock_fits_into,
1520 static int osc_lock_lockless_unuse(const struct lu_env *env,
1521 const struct cl_lock_slice *slice)
1523 struct osc_lock *ols = cl2osc_lock(slice);
1524 struct cl_lock *lock = slice->cls_lock;
1526 LASSERT(ols->ols_state == OLS_GRANTED);
1527 LINVRNT(osc_lock_invariant(ols));
1529 cl_lock_cancel(env, lock);
1530 cl_lock_delete(env, lock);
1534 static void osc_lock_lockless_cancel(const struct lu_env *env,
1535 const struct cl_lock_slice *slice)
1537 struct osc_lock *ols = cl2osc_lock(slice);
1540 result = osc_lock_flush(ols, 0);
1542 CERROR("Pages for lockless lock %p were not purged(%d)\n",
1544 ols->ols_state = OLS_CANCELLED;
1547 static int osc_lock_lockless_wait(const struct lu_env *env,
1548 const struct cl_lock_slice *slice)
1550 struct osc_lock *olck = cl2osc_lock(slice);
1551 struct cl_lock *lock = olck->ols_cl.cls_lock;
1553 LINVRNT(osc_lock_invariant(olck));
1554 LASSERT(olck->ols_state >= OLS_UPCALL_RECEIVED);
1556 return lock->cll_error;
1559 static void osc_lock_lockless_state(const struct lu_env *env,
1560 const struct cl_lock_slice *slice,
1561 enum cl_lock_state state)
1563 struct osc_lock *lock = cl2osc_lock(slice);
1565 LINVRNT(osc_lock_invariant(lock));
1566 if (state == CLS_HELD) {
1567 struct osc_io *oio = osc_env_io(env);
1569 LASSERT(ergo(lock->ols_owner, lock->ols_owner == oio));
1570 lock->ols_owner = oio;
1572 /* set the io to be lockless if this lock is for io's
1574 if (cl_object_same(oio->oi_cl.cis_obj, slice->cls_obj))
1575 oio->oi_lockless = 1;
1579 static int osc_lock_lockless_fits_into(const struct lu_env *env,
1580 const struct cl_lock_slice *slice,
1581 const struct cl_lock_descr *need,
1582 const struct cl_io *io)
1584 struct osc_lock *lock = cl2osc_lock(slice);
1586 if (!(need->cld_enq_flags & CEF_NEVER))
1589 /* lockless lock should only be used by its owning io. b22147 */
1590 return (lock->ols_owner == osc_env_io(env));
1593 static const struct cl_lock_operations osc_lock_lockless_ops = {
1594 .clo_fini = osc_lock_fini,
1595 .clo_enqueue = osc_lock_enqueue,
1596 .clo_wait = osc_lock_lockless_wait,
1597 .clo_unuse = osc_lock_lockless_unuse,
1598 .clo_state = osc_lock_lockless_state,
1599 .clo_fits_into = osc_lock_lockless_fits_into,
1600 .clo_cancel = osc_lock_lockless_cancel,
1601 .clo_print = osc_lock_print
1604 int osc_lock_init(const struct lu_env *env,
1605 struct cl_object *obj, struct cl_lock *lock,
1606 const struct cl_io *unused)
1608 struct osc_lock *clk;
1611 OBD_SLAB_ALLOC_PTR_GFP(clk, osc_lock_kmem, CFS_ALLOC_IO);
1613 osc_lock_build_einfo(env, lock, clk, &clk->ols_einfo);
1614 cfs_atomic_set(&clk->ols_pageref, 0);
1615 clk->ols_state = OLS_NEW;
1616 cl_lock_slice_add(lock, &clk->ols_cl, obj, &osc_lock_ops);
1623 int osc_dlm_lock_pageref(struct ldlm_lock *dlm)
1625 struct osc_lock *olock;
1628 cfs_spin_lock(&osc_ast_guard);
1629 olock = dlm->l_ast_data;
1631 * there's a very rare race with osc_page_addref_lock(), but that
1632 * doesn't matter because in the worst case we don't cancel a lock
1633 * which we actually can, that's no harm.
1635 if (olock != NULL &&
1636 cfs_atomic_add_return(_PAGEREF_MAGIC,
1637 &olock->ols_pageref) != _PAGEREF_MAGIC) {
1638 cfs_atomic_sub(_PAGEREF_MAGIC, &olock->ols_pageref);
1641 cfs_spin_unlock(&osc_ast_guard);