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27 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
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30 * Copyright (c) 2011, 2013, Intel Corporation.
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);
100 if (ergo(osc_lock_is_lockless(ols),
101 ols->ols_locklessable && ols->ols_lock == NULL))
105 * If all the following "ergo"s are true, return 1, otherwise 0
107 if (! ergo(olock != NULL, handle_used))
110 if (! ergo(olock != NULL,
111 olock->l_handle.h_cookie == ols->ols_handle.cookie))
114 if (! ergo(handle_used,
115 ergo(lock != NULL && olock != NULL, lock == olock) &&
116 ergo(lock == NULL, olock == NULL)))
119 * Check that ->ols_handle and ->ols_lock are consistent, but
120 * take into account that they are set at the different time.
122 if (! ergo(ols->ols_state == OLS_CANCELLED,
123 olock == NULL && !handle_used))
126 * DLM lock is destroyed only after we have seen cancellation
129 if (! ergo(olock != NULL && ols->ols_state < OLS_CANCELLED,
130 ((olock->l_flags & LDLM_FL_DESTROYED) == 0)))
133 if (! ergo(ols->ols_state == OLS_GRANTED,
135 olock->l_req_mode == olock->l_granted_mode &&
141 /*****************************************************************************
148 * Breaks a link between osc_lock and dlm_lock.
150 static void osc_lock_detach(const struct lu_env *env, struct osc_lock *olck)
152 struct ldlm_lock *dlmlock;
154 spin_lock(&osc_ast_guard);
155 dlmlock = olck->ols_lock;
156 if (dlmlock == NULL) {
157 spin_unlock(&osc_ast_guard);
161 olck->ols_lock = NULL;
162 /* wb(); --- for all who checks (ols->ols_lock != NULL) before
163 * call to osc_lock_detach() */
164 dlmlock->l_ast_data = NULL;
165 olck->ols_handle.cookie = 0ULL;
166 spin_unlock(&osc_ast_guard);
168 lock_res_and_lock(dlmlock);
169 if (dlmlock->l_granted_mode == dlmlock->l_req_mode) {
170 struct cl_object *obj = olck->ols_cl.cls_obj;
171 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
174 cl_object_attr_lock(obj);
175 /* Must get the value under the lock to avoid possible races. */
176 old_kms = cl2osc(obj)->oo_oinfo->loi_kms;
177 /* Update the kms. Need to loop all granted locks.
178 * Not a problem for the client */
179 attr->cat_kms = ldlm_extent_shift_kms(dlmlock, old_kms);
181 cl_object_attr_set(env, obj, attr, CAT_KMS);
182 cl_object_attr_unlock(obj);
184 unlock_res_and_lock(dlmlock);
186 /* release a reference taken in osc_lock_upcall0(). */
187 LASSERT(olck->ols_has_ref);
188 lu_ref_del(&dlmlock->l_reference, "osc_lock", olck);
189 LDLM_LOCK_RELEASE(dlmlock);
190 olck->ols_has_ref = 0;
193 static int osc_lock_unhold(struct osc_lock *ols)
199 result = osc_cancel_base(&ols->ols_handle,
200 ols->ols_einfo.ei_mode);
205 static int osc_lock_unuse(const struct lu_env *env,
206 const struct cl_lock_slice *slice)
208 struct osc_lock *ols = cl2osc_lock(slice);
210 LINVRNT(osc_lock_invariant(ols));
212 switch (ols->ols_state) {
214 LASSERT(!ols->ols_hold);
215 LASSERT(ols->ols_agl);
217 case OLS_UPCALL_RECEIVED:
218 osc_lock_unhold(ols);
220 LASSERT(!ols->ols_hold);
221 osc_lock_detach(env, ols);
222 ols->ols_state = OLS_NEW;
225 LASSERT(!ols->ols_glimpse);
226 LASSERT(ols->ols_hold);
228 * Move lock into OLS_RELEASED state before calling
229 * osc_cancel_base() so that possible synchronous cancellation
230 * (that always happens e.g., for liblustre) sees that lock is
233 ols->ols_state = OLS_RELEASED;
234 return osc_lock_unhold(ols);
236 CERROR("Impossible state: %d\n", ols->ols_state);
241 static void osc_lock_fini(const struct lu_env *env,
242 struct cl_lock_slice *slice)
244 struct osc_lock *ols = cl2osc_lock(slice);
246 LINVRNT(osc_lock_invariant(ols));
248 * ->ols_hold can still be true at this point if, for example, a
249 * thread that requested a lock was killed (and released a reference
250 * to the lock), before reply from a server was received. In this case
251 * lock is destroyed immediately after upcall.
253 osc_lock_unhold(ols);
254 LASSERT(ols->ols_lock == NULL);
255 LASSERT(cfs_atomic_read(&ols->ols_pageref) == 0 ||
256 cfs_atomic_read(&ols->ols_pageref) == _PAGEREF_MAGIC);
258 OBD_SLAB_FREE_PTR(ols, osc_lock_kmem);
261 static void osc_lock_build_policy(const struct lu_env *env,
262 const struct cl_lock *lock,
263 ldlm_policy_data_t *policy)
265 const struct cl_lock_descr *d = &lock->cll_descr;
267 osc_index2policy(policy, d->cld_obj, d->cld_start, d->cld_end);
268 policy->l_extent.gid = d->cld_gid;
271 static __u64 osc_enq2ldlm_flags(__u32 enqflags)
275 LASSERT((enqflags & ~CEF_MASK) == 0);
277 if (enqflags & CEF_NONBLOCK)
278 result |= LDLM_FL_BLOCK_NOWAIT;
279 if (enqflags & CEF_ASYNC)
280 result |= LDLM_FL_HAS_INTENT;
281 if (enqflags & CEF_DISCARD_DATA)
282 result |= LDLM_FL_AST_DISCARD_DATA;
287 * Global spin-lock protecting consistency of ldlm_lock::l_ast_data
288 * pointers. Initialized in osc_init().
290 spinlock_t osc_ast_guard;
292 static struct osc_lock *osc_ast_data_get(struct ldlm_lock *dlm_lock)
294 struct osc_lock *olck;
296 lock_res_and_lock(dlm_lock);
297 spin_lock(&osc_ast_guard);
298 olck = dlm_lock->l_ast_data;
300 struct cl_lock *lock = olck->ols_cl.cls_lock;
302 * If osc_lock holds a reference on ldlm lock, return it even
303 * when cl_lock is in CLS_FREEING state. This way
305 * osc_ast_data_get(dlmlock) == NULL
307 * guarantees that all osc references on dlmlock were
308 * released. osc_dlm_blocking_ast0() relies on that.
310 if (lock->cll_state < CLS_FREEING || olck->ols_has_ref) {
311 cl_lock_get_trust(lock);
312 lu_ref_add_atomic(&lock->cll_reference,
313 "ast", cfs_current());
317 spin_unlock(&osc_ast_guard);
318 unlock_res_and_lock(dlm_lock);
322 static void osc_ast_data_put(const struct lu_env *env, struct osc_lock *olck)
324 struct cl_lock *lock;
326 lock = olck->ols_cl.cls_lock;
327 lu_ref_del(&lock->cll_reference, "ast", cfs_current());
328 cl_lock_put(env, lock);
332 * Updates object attributes from a lock value block (lvb) received together
333 * with the DLM lock reply from the server. Copy of osc_update_enqueue()
336 * This can be optimized to not update attributes when lock is a result of a
339 * Called under lock and resource spin-locks.
341 static void osc_lock_lvb_update(const struct lu_env *env, struct osc_lock *olck,
345 struct cl_object *obj;
346 struct lov_oinfo *oinfo;
347 struct cl_attr *attr;
352 if (!(olck->ols_flags & LDLM_FL_LVB_READY))
355 lvb = &olck->ols_lvb;
356 obj = olck->ols_cl.cls_obj;
357 oinfo = cl2osc(obj)->oo_oinfo;
358 attr = &osc_env_info(env)->oti_attr;
359 valid = CAT_BLOCKS | CAT_ATIME | CAT_CTIME | CAT_MTIME | CAT_SIZE;
360 cl_lvb2attr(attr, lvb);
362 cl_object_attr_lock(obj);
364 struct ldlm_lock *dlmlock;
367 dlmlock = olck->ols_lock;
368 LASSERT(dlmlock != NULL);
370 /* re-grab LVB from a dlm lock under DLM spin-locks. */
371 *lvb = *(struct ost_lvb *)dlmlock->l_lvb_data;
372 size = lvb->lvb_size;
373 /* Extend KMS up to the end of this lock and no further
374 * A lock on [x,y] means a KMS of up to y + 1 bytes! */
375 if (size > dlmlock->l_policy_data.l_extent.end)
376 size = dlmlock->l_policy_data.l_extent.end + 1;
377 if (size >= oinfo->loi_kms) {
378 LDLM_DEBUG(dlmlock, "lock acquired, setting rss="LPU64
379 ", kms="LPU64, lvb->lvb_size, size);
381 attr->cat_kms = size;
383 LDLM_DEBUG(dlmlock, "lock acquired, setting rss="
384 LPU64"; leaving kms="LPU64", end="LPU64,
385 lvb->lvb_size, oinfo->loi_kms,
386 dlmlock->l_policy_data.l_extent.end);
388 ldlm_lock_allow_match_locked(dlmlock);
389 } else if (rc == -ENAVAIL && olck->ols_glimpse) {
390 CDEBUG(D_INODE, "glimpsed, setting rss="LPU64"; leaving"
391 " kms="LPU64"\n", lvb->lvb_size, oinfo->loi_kms);
396 cl_object_attr_set(env, obj, attr, valid);
398 cl_object_attr_unlock(obj);
404 * Called when a lock is granted, from an upcall (when server returned a
405 * granted lock), or from completion AST, when server returned a blocked lock.
407 * Called under lock and resource spin-locks, that are released temporarily
410 static void osc_lock_granted(const struct lu_env *env, struct osc_lock *olck,
411 struct ldlm_lock *dlmlock, int rc)
413 struct ldlm_extent *ext;
414 struct cl_lock *lock;
415 struct cl_lock_descr *descr;
417 LASSERT(dlmlock->l_granted_mode == dlmlock->l_req_mode);
420 if (olck->ols_state < OLS_GRANTED) {
421 lock = olck->ols_cl.cls_lock;
422 ext = &dlmlock->l_policy_data.l_extent;
423 descr = &osc_env_info(env)->oti_descr;
424 descr->cld_obj = lock->cll_descr.cld_obj;
426 /* XXX check that ->l_granted_mode is valid. */
427 descr->cld_mode = osc_ldlm2cl_lock(dlmlock->l_granted_mode);
428 descr->cld_start = cl_index(descr->cld_obj, ext->start);
429 descr->cld_end = cl_index(descr->cld_obj, ext->end);
430 descr->cld_gid = ext->gid;
432 * tell upper layers the extent of the lock that was actually
435 olck->ols_state = OLS_GRANTED;
436 osc_lock_lvb_update(env, olck, rc);
438 /* release DLM spin-locks to allow cl_lock_{modify,signal}()
439 * to take a semaphore on a parent lock. This is safe, because
440 * spin-locks are needed to protect consistency of
441 * dlmlock->l_*_mode and LVB, and we have finished processing
443 unlock_res_and_lock(dlmlock);
444 cl_lock_modify(env, lock, descr);
445 cl_lock_signal(env, lock);
446 LINVRNT(osc_lock_invariant(olck));
447 lock_res_and_lock(dlmlock);
452 static void osc_lock_upcall0(const struct lu_env *env, struct osc_lock *olck)
455 struct ldlm_lock *dlmlock;
459 dlmlock = ldlm_handle2lock_long(&olck->ols_handle, 0);
460 LASSERT(dlmlock != NULL);
462 lock_res_and_lock(dlmlock);
463 spin_lock(&osc_ast_guard);
464 LASSERT(dlmlock->l_ast_data == olck);
465 LASSERT(olck->ols_lock == NULL);
466 olck->ols_lock = dlmlock;
467 spin_unlock(&osc_ast_guard);
470 * Lock might be not yet granted. In this case, completion ast
471 * (osc_ldlm_completion_ast()) comes later and finishes lock
474 if (dlmlock->l_granted_mode == dlmlock->l_req_mode)
475 osc_lock_granted(env, olck, dlmlock, 0);
476 unlock_res_and_lock(dlmlock);
479 * osc_enqueue_interpret() decrefs asynchronous locks, counter
482 ldlm_lock_addref(&olck->ols_handle, olck->ols_einfo.ei_mode);
485 /* lock reference taken by ldlm_handle2lock_long() is owned by
486 * osc_lock and released in osc_lock_detach() */
487 lu_ref_add(&dlmlock->l_reference, "osc_lock", olck);
488 olck->ols_has_ref = 1;
492 * Lock upcall function that is executed either when a reply to ENQUEUE rpc is
493 * received from a server, or after osc_enqueue_base() matched a local DLM
496 static int osc_lock_upcall(void *cookie, int errcode)
498 struct osc_lock *olck = cookie;
499 struct cl_lock_slice *slice = &olck->ols_cl;
500 struct cl_lock *lock = slice->cls_lock;
502 struct cl_env_nest nest;
505 env = cl_env_nested_get(&nest);
509 cl_lock_mutex_get(env, lock);
511 LASSERT(lock->cll_state >= CLS_QUEUING);
512 if (olck->ols_state == OLS_ENQUEUED) {
513 olck->ols_state = OLS_UPCALL_RECEIVED;
514 rc = ldlm_error2errno(errcode);
515 } else if (olck->ols_state == OLS_CANCELLED) {
518 CERROR("Impossible state: %d\n", olck->ols_state);
522 struct ldlm_lock *dlmlock;
524 dlmlock = ldlm_handle2lock(&olck->ols_handle);
525 if (dlmlock != NULL) {
526 lock_res_and_lock(dlmlock);
527 spin_lock(&osc_ast_guard);
528 LASSERT(olck->ols_lock == NULL);
529 dlmlock->l_ast_data = NULL;
530 olck->ols_handle.cookie = 0ULL;
531 spin_unlock(&osc_ast_guard);
532 ldlm_lock_fail_match_locked(dlmlock);
533 unlock_res_and_lock(dlmlock);
534 LDLM_LOCK_PUT(dlmlock);
537 if (olck->ols_glimpse)
538 olck->ols_glimpse = 0;
539 osc_lock_upcall0(env, olck);
542 /* Error handling, some errors are tolerable. */
543 if (olck->ols_locklessable && rc == -EUSERS) {
544 /* This is a tolerable error, turn this lock into
547 osc_object_set_contended(cl2osc(slice->cls_obj));
548 LASSERT(slice->cls_ops == &osc_lock_ops);
550 /* Change this lock to ldlmlock-less lock. */
551 osc_lock_to_lockless(env, olck, 1);
552 olck->ols_state = OLS_GRANTED;
554 } else if (olck->ols_glimpse && rc == -ENAVAIL) {
555 osc_lock_lvb_update(env, olck, rc);
556 cl_lock_delete(env, lock);
557 /* Hide the error. */
562 /* For AGL case, the RPC sponsor may exits the cl_lock
563 * processing without wait() called before related OSC
564 * lock upcall(). So update the lock status according
565 * to the enqueue result inside AGL upcall(). */
567 lock->cll_flags |= CLF_FROM_UPCALL;
568 cl_wait_try(env, lock);
569 lock->cll_flags &= ~CLF_FROM_UPCALL;
570 if (!olck->ols_glimpse)
573 cl_lock_signal(env, lock);
574 /* del user for lock upcall cookie */
575 cl_unuse_try(env, lock);
577 /* del user for lock upcall cookie */
578 cl_lock_user_del(env, lock);
579 cl_lock_error(env, lock, rc);
582 /* release cookie reference, acquired by osc_lock_enqueue() */
583 cl_lock_hold_release(env, lock, "upcall", lock);
584 cl_lock_mutex_put(env, lock);
586 lu_ref_del(&lock->cll_reference, "upcall", lock);
587 /* This maybe the last reference, so must be called after
588 * cl_lock_mutex_put(). */
589 cl_lock_put(env, lock);
591 cl_env_nested_put(&nest, env);
593 /* should never happen, similar to osc_ldlm_blocking_ast(). */
600 * Core of osc_dlm_blocking_ast() logic.
602 static void osc_lock_blocking(const struct lu_env *env,
603 struct ldlm_lock *dlmlock,
604 struct osc_lock *olck, int blocking)
606 struct cl_lock *lock = olck->ols_cl.cls_lock;
608 LASSERT(olck->ols_lock == dlmlock);
609 CLASSERT(OLS_BLOCKED < OLS_CANCELLED);
610 LASSERT(!osc_lock_is_lockless(olck));
613 * Lock might be still addref-ed here, if e.g., blocking ast
614 * is sent for a failed lock.
616 osc_lock_unhold(olck);
618 if (blocking && olck->ols_state < OLS_BLOCKED)
620 * Move osc_lock into OLS_BLOCKED before canceling the lock,
621 * because it recursively re-enters osc_lock_blocking(), with
622 * the state set to OLS_CANCELLED.
624 olck->ols_state = OLS_BLOCKED;
626 * cancel and destroy lock at least once no matter how blocking ast is
627 * entered (see comment above osc_ldlm_blocking_ast() for use
628 * cases). cl_lock_cancel() and cl_lock_delete() are idempotent.
630 cl_lock_cancel(env, lock);
631 cl_lock_delete(env, lock);
635 * Helper for osc_dlm_blocking_ast() handling discrepancies between cl_lock
636 * and ldlm_lock caches.
638 static int osc_dlm_blocking_ast0(const struct lu_env *env,
639 struct ldlm_lock *dlmlock,
640 void *data, int flag)
642 struct osc_lock *olck;
643 struct cl_lock *lock;
647 LASSERT(flag == LDLM_CB_BLOCKING || flag == LDLM_CB_CANCELING);
650 olck = osc_ast_data_get(dlmlock);
652 lock = olck->ols_cl.cls_lock;
653 cl_lock_mutex_get(env, lock);
654 LINVRNT(osc_lock_invariant(olck));
655 if (olck->ols_ast_wait) {
656 /* wake up osc_lock_use() */
657 cl_lock_signal(env, lock);
658 olck->ols_ast_wait = 0;
661 * Lock might have been canceled while this thread was
662 * sleeping for lock mutex, but olck is pinned in memory.
664 if (olck == dlmlock->l_ast_data) {
666 * NOTE: DLM sends blocking AST's for failed locks
667 * (that are still in pre-OLS_GRANTED state)
668 * too, and they have to be canceled otherwise
669 * DLM lock is never destroyed and stuck in
672 * Alternatively, ldlm_cli_cancel() can be
673 * called here directly for osc_locks with
674 * ols_state < OLS_GRANTED to maintain an
675 * invariant that ->clo_cancel() is only called
676 * for locks that were granted.
678 LASSERT(data == olck);
679 osc_lock_blocking(env, dlmlock,
680 olck, flag == LDLM_CB_BLOCKING);
683 cl_lock_mutex_put(env, lock);
684 osc_ast_data_put(env, olck);
687 * DLM lock exists, but there is no cl_lock attached to it.
688 * This is a `normal' race. cl_object and its cl_lock's can be
689 * removed by memory pressure, together with all pages.
691 cancel = (flag == LDLM_CB_BLOCKING);
694 struct lustre_handle *lockh;
696 lockh = &osc_env_info(env)->oti_handle;
697 ldlm_lock2handle(dlmlock, lockh);
698 result = ldlm_cli_cancel(lockh, LCF_ASYNC);
705 * Blocking ast invoked by ldlm when dlm lock is either blocking progress of
706 * some other lock, or is canceled. This function is installed as a
707 * ldlm_lock::l_blocking_ast() for client extent locks.
709 * Control flow is tricky, because ldlm uses the same call-back
710 * (ldlm_lock::l_blocking_ast()) for both blocking and cancellation ast's.
712 * \param dlmlock lock for which ast occurred.
714 * \param new description of a conflicting lock in case of blocking ast.
716 * \param data value of dlmlock->l_ast_data
718 * \param flag LDLM_CB_BLOCKING or LDLM_CB_CANCELING. Used to distinguish
719 * cancellation and blocking ast's.
721 * Possible use cases:
723 * - ldlm calls dlmlock->l_blocking_ast(..., LDLM_CB_CANCELING) to cancel
724 * lock due to lock lru pressure, or explicit user request to purge
727 * - ldlm calls dlmlock->l_blocking_ast(..., LDLM_CB_BLOCKING) to notify
728 * us that dlmlock conflicts with another lock that some client is
729 * enqueing. Lock is canceled.
731 * - cl_lock_cancel() is called. osc_lock_cancel() calls
732 * ldlm_cli_cancel() that calls
734 * dlmlock->l_blocking_ast(..., LDLM_CB_CANCELING)
736 * recursively entering osc_ldlm_blocking_ast().
738 * - client cancels lock voluntary (e.g., as a part of early cancellation):
741 * osc_lock_cancel()->
742 * ldlm_cli_cancel()->
743 * dlmlock->l_blocking_ast(..., LDLM_CB_CANCELING)
746 static int osc_ldlm_blocking_ast(struct ldlm_lock *dlmlock,
747 struct ldlm_lock_desc *new, void *data,
751 struct cl_env_nest nest;
755 * This can be called in the context of outer IO, e.g.,
758 * ->osc_enqueue_base()->...
759 * ->ldlm_prep_elc_req()->...
760 * ->ldlm_cancel_callback()->...
761 * ->osc_ldlm_blocking_ast()
763 * new environment has to be created to not corrupt outer context.
765 env = cl_env_nested_get(&nest);
767 result = osc_dlm_blocking_ast0(env, dlmlock, data, flag);
768 cl_env_nested_put(&nest, env);
770 result = PTR_ERR(env);
772 * XXX This should never happen, as cl_lock is
773 * stuck. Pre-allocated environment a la vvp_inode_fini_env
779 if (result == -ENODATA)
782 CERROR("BAST failed: %d\n", result);
787 static int osc_ldlm_completion_ast(struct ldlm_lock *dlmlock,
788 __u64 flags, void *data)
790 struct cl_env_nest nest;
792 struct osc_lock *olck;
793 struct cl_lock *lock;
797 /* first, do dlm part of the work */
798 dlmrc = ldlm_completion_ast_async(dlmlock, flags, data);
799 /* then, notify cl_lock */
800 env = cl_env_nested_get(&nest);
802 olck = osc_ast_data_get(dlmlock);
804 lock = olck->ols_cl.cls_lock;
805 cl_lock_mutex_get(env, lock);
807 * ldlm_handle_cp_callback() copied LVB from request
808 * to lock->l_lvb_data, store it in osc_lock.
810 LASSERT(dlmlock->l_lvb_data != NULL);
811 lock_res_and_lock(dlmlock);
812 olck->ols_lvb = *(struct ost_lvb *)dlmlock->l_lvb_data;
813 if (olck->ols_lock == NULL) {
815 * upcall (osc_lock_upcall()) hasn't yet been
816 * called. Do nothing now, upcall will bind
817 * olck to dlmlock and signal the waiters.
819 * This maintains an invariant that osc_lock
820 * and ldlm_lock are always bound when
821 * osc_lock is in OLS_GRANTED state.
823 } else if (dlmlock->l_granted_mode ==
824 dlmlock->l_req_mode) {
825 osc_lock_granted(env, olck, dlmlock, dlmrc);
827 unlock_res_and_lock(dlmlock);
830 CL_LOCK_DEBUG(D_ERROR, env, lock,
831 "dlmlock returned %d\n", dlmrc);
832 cl_lock_error(env, lock, dlmrc);
834 cl_lock_mutex_put(env, lock);
835 osc_ast_data_put(env, olck);
838 result = -ELDLM_NO_LOCK_DATA;
839 cl_env_nested_put(&nest, env);
841 result = PTR_ERR(env);
842 return dlmrc ?: result;
845 static int osc_ldlm_glimpse_ast(struct ldlm_lock *dlmlock, void *data)
847 struct ptlrpc_request *req = data;
848 struct osc_lock *olck;
849 struct cl_lock *lock;
850 struct cl_object *obj;
851 struct cl_env_nest nest;
854 struct req_capsule *cap;
857 LASSERT(lustre_msg_get_opc(req->rq_reqmsg) == LDLM_GL_CALLBACK);
859 env = cl_env_nested_get(&nest);
861 /* osc_ast_data_get() has to go after environment is
862 * allocated, because osc_ast_data() acquires a
863 * reference to a lock, and it can only be released in
866 olck = osc_ast_data_get(dlmlock);
868 lock = olck->ols_cl.cls_lock;
869 /* Do not grab the mutex of cl_lock for glimpse.
870 * See LU-1274 for details.
871 * BTW, it's okay for cl_lock to be cancelled during
872 * this period because server can handle this race.
873 * See ldlm_server_glimpse_ast() for details.
874 * cl_lock_mutex_get(env, lock); */
876 req_capsule_extend(cap, &RQF_LDLM_GL_CALLBACK);
877 req_capsule_set_size(cap, &RMF_DLM_LVB, RCL_SERVER,
879 result = req_capsule_server_pack(cap);
881 lvb = req_capsule_server_get(cap, &RMF_DLM_LVB);
882 obj = lock->cll_descr.cld_obj;
883 result = cl_object_glimpse(env, obj, lvb);
885 if (!exp_connect_lvb_type(req->rq_export))
886 req_capsule_shrink(&req->rq_pill,
888 sizeof(struct ost_lvb_v1),
890 osc_ast_data_put(env, olck);
893 * These errors are normal races, so we don't want to
894 * fill the console with messages by calling
897 lustre_pack_reply(req, 1, NULL, NULL);
898 result = -ELDLM_NO_LOCK_DATA;
900 cl_env_nested_put(&nest, env);
902 result = PTR_ERR(env);
903 req->rq_status = result;
907 static unsigned long osc_lock_weigh(const struct lu_env *env,
908 const struct cl_lock_slice *slice)
911 * don't need to grab coh_page_guard since we don't care the exact #
914 return cl_object_header(slice->cls_obj)->coh_pages;
917 static void osc_lock_build_einfo(const struct lu_env *env,
918 const struct cl_lock *clock,
919 struct osc_lock *lock,
920 struct ldlm_enqueue_info *einfo)
922 enum cl_lock_mode mode;
924 mode = clock->cll_descr.cld_mode;
925 if (mode == CLM_PHANTOM)
927 * For now, enqueue all glimpse locks in read mode. In the
928 * future, client might choose to enqueue LCK_PW lock for
929 * glimpse on a file opened for write.
933 einfo->ei_type = LDLM_EXTENT;
934 einfo->ei_mode = osc_cl_lock2ldlm(mode);
935 einfo->ei_cb_bl = osc_ldlm_blocking_ast;
936 einfo->ei_cb_cp = osc_ldlm_completion_ast;
937 einfo->ei_cb_gl = osc_ldlm_glimpse_ast;
938 einfo->ei_cbdata = lock; /* value to be put into ->l_ast_data */
942 * Determine if the lock should be converted into a lockless lock.
945 * - if the lock has an explicite requirment for a non-lockless lock;
946 * - if the io lock request type ci_lockreq;
947 * - send the enqueue rpc to ost to make the further decision;
948 * - special treat to truncate lockless lock
950 * Additional policy can be implemented here, e.g., never do lockless-io
953 static void osc_lock_to_lockless(const struct lu_env *env,
954 struct osc_lock *ols, int force)
956 struct cl_lock_slice *slice = &ols->ols_cl;
958 LASSERT(ols->ols_state == OLS_NEW ||
959 ols->ols_state == OLS_UPCALL_RECEIVED);
962 ols->ols_locklessable = 1;
963 slice->cls_ops = &osc_lock_lockless_ops;
965 struct osc_io *oio = osc_env_io(env);
966 struct cl_io *io = oio->oi_cl.cis_io;
967 struct cl_object *obj = slice->cls_obj;
968 struct osc_object *oob = cl2osc(obj);
969 const struct osc_device *osd = lu2osc_dev(obj->co_lu.lo_dev);
970 struct obd_connect_data *ocd;
972 LASSERT(io->ci_lockreq == CILR_MANDATORY ||
973 io->ci_lockreq == CILR_MAYBE ||
974 io->ci_lockreq == CILR_NEVER);
976 ocd = &class_exp2cliimp(osc_export(oob))->imp_connect_data;
977 ols->ols_locklessable = (io->ci_type != CIT_SETATTR) &&
978 (io->ci_lockreq == CILR_MAYBE) &&
979 (ocd->ocd_connect_flags & OBD_CONNECT_SRVLOCK);
980 if (io->ci_lockreq == CILR_NEVER ||
982 (ols->ols_locklessable && osc_object_is_contended(oob)) ||
983 /* lockless truncate */
984 (cl_io_is_trunc(io) &&
985 (ocd->ocd_connect_flags & OBD_CONNECT_TRUNCLOCK) &&
986 osd->od_lockless_truncate)) {
987 ols->ols_locklessable = 1;
988 slice->cls_ops = &osc_lock_lockless_ops;
991 LASSERT(ergo(ols->ols_glimpse, !osc_lock_is_lockless(ols)));
994 static int osc_lock_compatible(const struct osc_lock *qing,
995 const struct osc_lock *qed)
997 enum cl_lock_mode qing_mode;
998 enum cl_lock_mode qed_mode;
1000 qing_mode = qing->ols_cl.cls_lock->cll_descr.cld_mode;
1001 if (qed->ols_glimpse &&
1002 (qed->ols_state >= OLS_UPCALL_RECEIVED || qing_mode == CLM_READ))
1005 qed_mode = qed->ols_cl.cls_lock->cll_descr.cld_mode;
1006 return ((qing_mode == CLM_READ) && (qed_mode == CLM_READ));
1010 * Cancel all conflicting locks and wait for them to be destroyed.
1012 * This function is used for two purposes:
1014 * - early cancel all conflicting locks before starting IO, and
1016 * - guarantee that pages added to the page cache by lockless IO are never
1017 * covered by locks other than lockless IO lock, and, hence, are not
1018 * visible to other threads.
1020 static int osc_lock_enqueue_wait(const struct lu_env *env,
1021 const struct osc_lock *olck)
1023 struct cl_lock *lock = olck->ols_cl.cls_lock;
1024 struct cl_lock_descr *descr = &lock->cll_descr;
1025 struct cl_object_header *hdr = cl_object_header(descr->cld_obj);
1026 struct cl_lock *scan;
1027 struct cl_lock *conflict= NULL;
1028 int lockless = osc_lock_is_lockless(olck);
1032 LASSERT(cl_lock_is_mutexed(lock));
1034 /* make it enqueue anyway for glimpse lock, because we actually
1035 * don't need to cancel any conflicting locks. */
1036 if (olck->ols_glimpse)
1039 spin_lock(&hdr->coh_lock_guard);
1040 cfs_list_for_each_entry(scan, &hdr->coh_locks, cll_linkage) {
1041 struct cl_lock_descr *cld = &scan->cll_descr;
1042 const struct osc_lock *scan_ols;
1047 if (scan->cll_state < CLS_QUEUING ||
1048 scan->cll_state == CLS_FREEING ||
1049 cld->cld_start > descr->cld_end ||
1050 cld->cld_end < descr->cld_start)
1053 /* overlapped and living locks. */
1055 /* We're not supposed to give up group lock. */
1056 if (scan->cll_descr.cld_mode == CLM_GROUP) {
1057 LASSERT(descr->cld_mode != CLM_GROUP ||
1058 descr->cld_gid != scan->cll_descr.cld_gid);
1062 scan_ols = osc_lock_at(scan);
1064 /* We need to cancel the compatible locks if we're enqueuing
1065 * a lockless lock, for example:
1066 * imagine that client has PR lock on [0, 1000], and thread T0
1067 * is doing lockless IO in [500, 1500] region. Concurrent
1068 * thread T1 can see lockless data in [500, 1000], which is
1069 * wrong, because these data are possibly stale. */
1070 if (!lockless && osc_lock_compatible(olck, scan_ols))
1073 cl_lock_get_trust(scan);
1077 spin_unlock(&hdr->coh_lock_guard);
1080 if (lock->cll_descr.cld_mode == CLM_GROUP) {
1081 /* we want a group lock but a previous lock request
1082 * conflicts, we do not wait but return 0 so the
1083 * request is send to the server
1085 CDEBUG(D_DLMTRACE, "group lock %p is conflicted "
1086 "with %p, no wait, send to server\n",
1088 cl_lock_put(env, conflict);
1091 CDEBUG(D_DLMTRACE, "lock %p is conflicted with %p, "
1094 LASSERT(lock->cll_conflict == NULL);
1095 lu_ref_add(&conflict->cll_reference, "cancel-wait",
1097 lock->cll_conflict = conflict;
1105 * Implementation of cl_lock_operations::clo_enqueue() method for osc
1106 * layer. This initiates ldlm enqueue:
1108 * - cancels conflicting locks early (osc_lock_enqueue_wait());
1110 * - calls osc_enqueue_base() to do actual enqueue.
1112 * osc_enqueue_base() is supplied with an upcall function that is executed
1113 * when lock is received either after a local cached ldlm lock is matched, or
1114 * when a reply from the server is received.
1116 * This function does not wait for the network communication to complete.
1118 static int osc_lock_enqueue(const struct lu_env *env,
1119 const struct cl_lock_slice *slice,
1120 struct cl_io *unused, __u32 enqflags)
1122 struct osc_lock *ols = cl2osc_lock(slice);
1123 struct cl_lock *lock = ols->ols_cl.cls_lock;
1127 LASSERT(cl_lock_is_mutexed(lock));
1128 LASSERTF(ols->ols_state == OLS_NEW,
1129 "Impossible state: %d\n", ols->ols_state);
1131 LASSERTF(ergo(ols->ols_glimpse, lock->cll_descr.cld_mode <= CLM_READ),
1132 "lock = %p, ols = %p\n", lock, ols);
1134 result = osc_lock_enqueue_wait(env, ols);
1136 if (!osc_lock_is_lockless(ols)) {
1137 struct osc_object *obj = cl2osc(slice->cls_obj);
1138 struct osc_thread_info *info = osc_env_info(env);
1139 struct ldlm_res_id *resname = &info->oti_resname;
1140 ldlm_policy_data_t *policy = &info->oti_policy;
1141 struct ldlm_enqueue_info *einfo = &ols->ols_einfo;
1143 /* lock will be passed as upcall cookie,
1144 * hold ref to prevent to be released. */
1145 cl_lock_hold_add(env, lock, "upcall", lock);
1146 /* a user for lock also */
1147 cl_lock_user_add(env, lock);
1148 ols->ols_state = OLS_ENQUEUED;
1151 * XXX: this is possible blocking point as
1152 * ldlm_lock_match(LDLM_FL_LVB_READY) waits for
1155 ostid_build_res_name(&obj->oo_oinfo->loi_oi, resname);
1156 osc_lock_build_policy(env, lock, policy);
1157 result = osc_enqueue_base(osc_export(obj), resname,
1158 &ols->ols_flags, policy,
1160 obj->oo_oinfo->loi_kms_valid,
1162 ols, einfo, &ols->ols_handle,
1163 PTLRPCD_SET, 1, ols->ols_agl);
1165 cl_lock_user_del(env, lock);
1166 cl_lock_unhold(env, lock, "upcall", lock);
1167 if (unlikely(result == -ECANCELED)) {
1168 ols->ols_state = OLS_NEW;
1173 ols->ols_state = OLS_GRANTED;
1174 ols->ols_owner = osc_env_io(env);
1177 LASSERT(ergo(ols->ols_glimpse, !osc_lock_is_lockless(ols)));
1181 static int osc_lock_wait(const struct lu_env *env,
1182 const struct cl_lock_slice *slice)
1184 struct osc_lock *olck = cl2osc_lock(slice);
1185 struct cl_lock *lock = olck->ols_cl.cls_lock;
1187 LINVRNT(osc_lock_invariant(olck));
1189 if (olck->ols_glimpse && olck->ols_state >= OLS_UPCALL_RECEIVED) {
1190 if (olck->ols_flags & LDLM_FL_LVB_READY) {
1192 } else if (olck->ols_agl) {
1193 if (lock->cll_flags & CLF_FROM_UPCALL)
1194 /* It is from enqueue RPC reply upcall for
1195 * updating state. Do not re-enqueue. */
1198 olck->ols_state = OLS_NEW;
1200 LASSERT(lock->cll_error);
1201 return lock->cll_error;
1205 if (olck->ols_state == OLS_NEW) {
1208 LASSERT(olck->ols_agl);
1210 rc = osc_lock_enqueue(env, slice, NULL, CEF_ASYNC | CEF_MUST);
1214 return CLO_REENQUEUED;
1217 LASSERT(equi(olck->ols_state >= OLS_UPCALL_RECEIVED &&
1218 lock->cll_error == 0, olck->ols_lock != NULL));
1220 return lock->cll_error ?: olck->ols_state >= OLS_GRANTED ? 0 : CLO_WAIT;
1224 * An implementation of cl_lock_operations::clo_use() method that pins cached
1227 static int osc_lock_use(const struct lu_env *env,
1228 const struct cl_lock_slice *slice)
1230 struct osc_lock *olck = cl2osc_lock(slice);
1233 LASSERT(!olck->ols_hold);
1236 * Atomically check for LDLM_FL_CBPENDING and addref a lock if this
1237 * flag is not set. This protects us from a concurrent blocking ast.
1239 rc = ldlm_lock_addref_try(&olck->ols_handle, olck->ols_einfo.ei_mode);
1242 olck->ols_state = OLS_GRANTED;
1244 struct cl_lock *lock;
1247 * Lock is being cancelled somewhere within
1248 * ldlm_handle_bl_callback(): LDLM_FL_CBPENDING is already
1249 * set, but osc_ldlm_blocking_ast() hasn't yet acquired
1252 lock = slice->cls_lock;
1253 LASSERT(lock->cll_state == CLS_INTRANSIT);
1254 LASSERT(lock->cll_users > 0);
1255 /* set a flag for osc_dlm_blocking_ast0() to signal the
1257 olck->ols_ast_wait = 1;
1263 static int osc_lock_flush(struct osc_lock *ols, int discard)
1265 struct cl_lock *lock = ols->ols_cl.cls_lock;
1266 struct cl_env_nest nest;
1271 env = cl_env_nested_get(&nest);
1273 struct osc_object *obj = cl2osc(ols->ols_cl.cls_obj);
1274 struct cl_lock_descr *descr = &lock->cll_descr;
1277 if (descr->cld_mode >= CLM_WRITE) {
1278 result = osc_cache_writeback_range(env, obj,
1279 descr->cld_start, descr->cld_end,
1281 LDLM_DEBUG(ols->ols_lock,
1282 "lock %p: %d pages were %s.\n", lock, result,
1283 discard ? "discarded" : "written");
1288 rc = cl_lock_discard_pages(env, lock);
1289 if (result == 0 && rc < 0)
1292 cl_env_nested_put(&nest, env);
1294 result = PTR_ERR(env);
1297 LINVRNT(!osc_lock_has_pages(ols));
1303 * Implements cl_lock_operations::clo_cancel() method for osc layer. This is
1304 * called (as part of cl_lock_cancel()) when lock is canceled either voluntary
1305 * (LRU pressure, early cancellation, umount, etc.) or due to the conflict
1306 * with some other lock some where in the cluster. This function does the
1309 * - invalidates all pages protected by this lock (after sending dirty
1310 * ones to the server, as necessary);
1312 * - decref's underlying ldlm lock;
1314 * - cancels ldlm lock (ldlm_cli_cancel()).
1316 static void osc_lock_cancel(const struct lu_env *env,
1317 const struct cl_lock_slice *slice)
1319 struct cl_lock *lock = slice->cls_lock;
1320 struct osc_lock *olck = cl2osc_lock(slice);
1321 struct ldlm_lock *dlmlock = olck->ols_lock;
1325 LASSERT(cl_lock_is_mutexed(lock));
1326 LINVRNT(osc_lock_invariant(olck));
1328 if (dlmlock != NULL) {
1331 discard = !!(dlmlock->l_flags & LDLM_FL_DISCARD_DATA);
1332 if (olck->ols_state >= OLS_GRANTED)
1333 result = osc_lock_flush(olck, discard);
1334 osc_lock_unhold(olck);
1336 lock_res_and_lock(dlmlock);
1337 /* Now that we're the only user of dlm read/write reference,
1338 * mostly the ->l_readers + ->l_writers should be zero.
1339 * However, there is a corner case.
1340 * See bug 18829 for details.*/
1341 do_cancel = (dlmlock->l_readers == 0 &&
1342 dlmlock->l_writers == 0);
1343 dlmlock->l_flags |= LDLM_FL_CBPENDING;
1344 unlock_res_and_lock(dlmlock);
1346 result = ldlm_cli_cancel(&olck->ols_handle, LCF_ASYNC);
1348 CL_LOCK_DEBUG(D_ERROR, env, lock,
1349 "lock %p cancel failure with error(%d)\n",
1352 olck->ols_state = OLS_CANCELLED;
1353 olck->ols_flags &= ~LDLM_FL_LVB_READY;
1354 osc_lock_detach(env, olck);
1357 #ifdef CONFIG_LUSTRE_DEBUG_EXPENSIVE_CHECK
1358 static int check_cb(const struct lu_env *env, struct cl_io *io,
1359 struct cl_page *page, void *cbdata)
1361 struct cl_lock *lock = cbdata;
1363 if (lock->cll_descr.cld_mode == CLM_READ) {
1364 struct cl_lock *tmp;
1365 tmp = cl_lock_at_page(env, lock->cll_descr.cld_obj,
1368 cl_lock_put(env, tmp);
1369 return CLP_GANG_OKAY;
1373 CL_LOCK_DEBUG(D_ERROR, env, lock, "still has pages\n");
1374 CL_PAGE_DEBUG(D_ERROR, env, page, "\n");
1375 return CLP_GANG_ABORT;
1379 * Returns true iff there are pages under \a olck not protected by other
1382 static int osc_lock_has_pages(struct osc_lock *olck)
1384 struct cl_lock *lock;
1385 struct cl_lock_descr *descr;
1386 struct cl_object *obj;
1387 struct osc_object *oob;
1388 struct cl_env_nest nest;
1393 env = cl_env_nested_get(&nest);
1397 obj = olck->ols_cl.cls_obj;
1399 io = &oob->oo_debug_io;
1400 lock = olck->ols_cl.cls_lock;
1401 descr = &lock->cll_descr;
1403 mutex_lock(&oob->oo_debug_mutex);
1405 io->ci_obj = cl_object_top(obj);
1406 io->ci_ignore_layout = 1;
1407 cl_io_init(env, io, CIT_MISC, io->ci_obj);
1409 result = cl_page_gang_lookup(env, obj, io,
1410 descr->cld_start, descr->cld_end,
1411 check_cb, (void *)lock);
1412 if (result == CLP_GANG_ABORT)
1414 if (result == CLP_GANG_RESCHED)
1416 } while (result != CLP_GANG_OKAY);
1417 cl_io_fini(env, io);
1418 mutex_unlock(&oob->oo_debug_mutex);
1419 cl_env_nested_put(&nest, env);
1421 return (result == CLP_GANG_ABORT);
1424 static int osc_lock_has_pages(struct osc_lock *olck)
1428 #endif /* CONFIG_LUSTRE_DEBUG_EXPENSIVE_CHECK */
1430 static void osc_lock_delete(const struct lu_env *env,
1431 const struct cl_lock_slice *slice)
1433 struct osc_lock *olck;
1435 olck = cl2osc_lock(slice);
1436 if (olck->ols_glimpse) {
1437 LASSERT(!olck->ols_hold);
1438 LASSERT(!olck->ols_lock);
1442 LINVRNT(osc_lock_invariant(olck));
1443 LINVRNT(!osc_lock_has_pages(olck));
1445 osc_lock_unhold(olck);
1446 osc_lock_detach(env, olck);
1450 * Implements cl_lock_operations::clo_state() method for osc layer.
1452 * Maintains osc_lock::ols_owner field.
1454 * This assumes that lock always enters CLS_HELD (from some other state) in
1455 * the same IO context as one that requested the lock. This should not be a
1456 * problem, because context is by definition shared by all activity pertaining
1457 * to the same high-level IO.
1459 static void osc_lock_state(const struct lu_env *env,
1460 const struct cl_lock_slice *slice,
1461 enum cl_lock_state state)
1463 struct osc_lock *lock = cl2osc_lock(slice);
1466 * XXX multiple io contexts can use the lock at the same time.
1468 LINVRNT(osc_lock_invariant(lock));
1469 if (state == CLS_HELD && slice->cls_lock->cll_state != CLS_HELD) {
1470 struct osc_io *oio = osc_env_io(env);
1472 LASSERT(lock->ols_owner == NULL);
1473 lock->ols_owner = oio;
1474 } else if (state != CLS_HELD)
1475 lock->ols_owner = NULL;
1478 static int osc_lock_print(const struct lu_env *env, void *cookie,
1479 lu_printer_t p, const struct cl_lock_slice *slice)
1481 struct osc_lock *lock = cl2osc_lock(slice);
1484 * XXX print ldlm lock and einfo properly.
1486 (*p)(env, cookie, "%p %#16llx "LPX64" %d %p ",
1487 lock->ols_lock, lock->ols_flags, lock->ols_handle.cookie,
1488 lock->ols_state, lock->ols_owner);
1489 osc_lvb_print(env, cookie, p, &lock->ols_lvb);
1493 static int osc_lock_fits_into(const struct lu_env *env,
1494 const struct cl_lock_slice *slice,
1495 const struct cl_lock_descr *need,
1496 const struct cl_io *io)
1498 struct osc_lock *ols = cl2osc_lock(slice);
1500 if (need->cld_enq_flags & CEF_NEVER)
1503 if (ols->ols_state >= OLS_CANCELLED)
1506 if (need->cld_mode == CLM_PHANTOM) {
1508 return !(ols->ols_state > OLS_RELEASED);
1511 * Note: the QUEUED lock can't be matched here, otherwise
1512 * it might cause the deadlocks.
1514 * P1: enqueued read lock, create sublock1
1515 * P2: enqueued write lock, create sublock2(conflicted
1517 * P1: Grant read lock.
1518 * P1: enqueued glimpse lock(with holding sublock1_read),
1519 * matched with sublock2, waiting sublock2 to be granted.
1520 * But sublock2 can not be granted, because P1
1521 * will not release sublock1. Bang!
1523 if (ols->ols_state < OLS_GRANTED ||
1524 ols->ols_state > OLS_RELEASED)
1526 } else if (need->cld_enq_flags & CEF_MUST) {
1528 * If the lock hasn't ever enqueued, it can't be matched
1529 * because enqueue process brings in many information
1530 * which can be used to determine things such as lockless,
1533 if (ols->ols_state < OLS_UPCALL_RECEIVED &&
1534 ols->ols_locklessable)
1540 static const struct cl_lock_operations osc_lock_ops = {
1541 .clo_fini = osc_lock_fini,
1542 .clo_enqueue = osc_lock_enqueue,
1543 .clo_wait = osc_lock_wait,
1544 .clo_unuse = osc_lock_unuse,
1545 .clo_use = osc_lock_use,
1546 .clo_delete = osc_lock_delete,
1547 .clo_state = osc_lock_state,
1548 .clo_cancel = osc_lock_cancel,
1549 .clo_weigh = osc_lock_weigh,
1550 .clo_print = osc_lock_print,
1551 .clo_fits_into = osc_lock_fits_into,
1554 static int osc_lock_lockless_unuse(const struct lu_env *env,
1555 const struct cl_lock_slice *slice)
1557 struct osc_lock *ols = cl2osc_lock(slice);
1558 struct cl_lock *lock = slice->cls_lock;
1560 LASSERT(ols->ols_state == OLS_GRANTED);
1561 LINVRNT(osc_lock_invariant(ols));
1563 cl_lock_cancel(env, lock);
1564 cl_lock_delete(env, lock);
1568 static void osc_lock_lockless_cancel(const struct lu_env *env,
1569 const struct cl_lock_slice *slice)
1571 struct osc_lock *ols = cl2osc_lock(slice);
1574 result = osc_lock_flush(ols, 0);
1576 CERROR("Pages for lockless lock %p were not purged(%d)\n",
1578 ols->ols_state = OLS_CANCELLED;
1581 static int osc_lock_lockless_wait(const struct lu_env *env,
1582 const struct cl_lock_slice *slice)
1584 struct osc_lock *olck = cl2osc_lock(slice);
1585 struct cl_lock *lock = olck->ols_cl.cls_lock;
1587 LINVRNT(osc_lock_invariant(olck));
1588 LASSERT(olck->ols_state >= OLS_UPCALL_RECEIVED);
1590 return lock->cll_error;
1593 static void osc_lock_lockless_state(const struct lu_env *env,
1594 const struct cl_lock_slice *slice,
1595 enum cl_lock_state state)
1597 struct osc_lock *lock = cl2osc_lock(slice);
1599 LINVRNT(osc_lock_invariant(lock));
1600 if (state == CLS_HELD) {
1601 struct osc_io *oio = osc_env_io(env);
1603 LASSERT(ergo(lock->ols_owner, lock->ols_owner == oio));
1604 lock->ols_owner = oio;
1606 /* set the io to be lockless if this lock is for io's
1608 if (cl_object_same(oio->oi_cl.cis_obj, slice->cls_obj))
1609 oio->oi_lockless = 1;
1613 static int osc_lock_lockless_fits_into(const struct lu_env *env,
1614 const struct cl_lock_slice *slice,
1615 const struct cl_lock_descr *need,
1616 const struct cl_io *io)
1618 struct osc_lock *lock = cl2osc_lock(slice);
1620 if (!(need->cld_enq_flags & CEF_NEVER))
1623 /* lockless lock should only be used by its owning io. b22147 */
1624 return (lock->ols_owner == osc_env_io(env));
1627 static const struct cl_lock_operations osc_lock_lockless_ops = {
1628 .clo_fini = osc_lock_fini,
1629 .clo_enqueue = osc_lock_enqueue,
1630 .clo_wait = osc_lock_lockless_wait,
1631 .clo_unuse = osc_lock_lockless_unuse,
1632 .clo_state = osc_lock_lockless_state,
1633 .clo_fits_into = osc_lock_lockless_fits_into,
1634 .clo_cancel = osc_lock_lockless_cancel,
1635 .clo_print = osc_lock_print
1638 int osc_lock_init(const struct lu_env *env,
1639 struct cl_object *obj, struct cl_lock *lock,
1640 const struct cl_io *unused)
1642 struct osc_lock *clk;
1645 OBD_SLAB_ALLOC_PTR_GFP(clk, osc_lock_kmem, __GFP_IO);
1647 __u32 enqflags = lock->cll_descr.cld_enq_flags;
1649 osc_lock_build_einfo(env, lock, clk, &clk->ols_einfo);
1650 cfs_atomic_set(&clk->ols_pageref, 0);
1651 clk->ols_state = OLS_NEW;
1653 clk->ols_flags = osc_enq2ldlm_flags(enqflags);
1654 clk->ols_agl = !!(enqflags & CEF_AGL);
1656 clk->ols_flags |= LDLM_FL_BLOCK_NOWAIT;
1657 if (clk->ols_flags & LDLM_FL_HAS_INTENT)
1658 clk->ols_glimpse = 1;
1660 cl_lock_slice_add(lock, &clk->ols_cl, obj, &osc_lock_ops);
1662 if (!(enqflags & CEF_MUST))
1663 /* try to convert this lock to a lockless lock */
1664 osc_lock_to_lockless(env, clk, (enqflags & CEF_NEVER));
1665 if (clk->ols_locklessable && !(enqflags & CEF_DISCARD_DATA))
1666 clk->ols_flags |= LDLM_FL_DENY_ON_CONTENTION;
1668 LDLM_DEBUG_NOLOCK("lock %p, osc lock %p, flags %llx\n",
1669 lock, clk, clk->ols_flags);
1677 int osc_dlm_lock_pageref(struct ldlm_lock *dlm)
1679 struct osc_lock *olock;
1682 spin_lock(&osc_ast_guard);
1683 olock = dlm->l_ast_data;
1685 * there's a very rare race with osc_page_addref_lock(), but that
1686 * doesn't matter because in the worst case we don't cancel a lock
1687 * which we actually can, that's no harm.
1689 if (olock != NULL &&
1690 cfs_atomic_add_return(_PAGEREF_MAGIC,
1691 &olock->ols_pageref) != _PAGEREF_MAGIC) {
1692 cfs_atomic_sub(_PAGEREF_MAGIC, &olock->ols_pageref);
1695 spin_unlock(&osc_ast_guard);