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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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 LOV layer.
38 * Author: Nikita Danilov <nikita.danilov@sun.com>
41 #define DEBUG_SUBSYSTEM S_LOV
43 #include "lov_cl_internal.h"
49 static struct cl_lock_closure *lov_closure_get(const struct lu_env *env,
50 struct cl_lock *parent);
52 static int lov_lock_unuse(const struct lu_env *env,
53 const struct cl_lock_slice *slice);
54 /*****************************************************************************
56 * Lov lock operations.
60 static struct lov_sublock_env *lov_sublock_env_get(const struct lu_env *env,
61 struct cl_lock *parent,
62 struct lov_lock_sub *lls)
64 struct lov_sublock_env *subenv;
65 struct lov_io *lio = lov_env_io(env);
66 struct cl_io *io = lio->lis_cl.cis_io;
67 struct lov_io_sub *sub;
69 subenv = &lov_env_session(env)->ls_subenv;
72 * FIXME: We tend to use the subio's env & io to call the sublock
73 * lock operations because osc lock sometimes stores some control
74 * variables in thread's IO infomation(Now only lockless information).
75 * However, if the lock's host(object) is different from the object
76 * for current IO, we have no way to get the subenv and subio because
77 * they are not initialized at all. As a temp fix, in this case,
78 * we still borrow the parent's env to call sublock operations.
80 if (!io || !cl_object_same(io->ci_obj, parent->cll_descr.cld_obj)) {
81 subenv->lse_env = env;
83 subenv->lse_sub = NULL;
85 sub = lov_sub_get(env, lio, lls->sub_stripe);
87 subenv->lse_env = sub->sub_env;
88 subenv->lse_io = sub->sub_io;
89 subenv->lse_sub = sub;
97 static void lov_sublock_env_put(struct lov_sublock_env *subenv)
99 if (subenv && subenv->lse_sub)
100 lov_sub_put(subenv->lse_sub);
103 static void lov_sublock_adopt(const struct lu_env *env, struct lov_lock *lck,
104 struct cl_lock *sublock, int idx,
105 struct lov_lock_link *link)
107 struct lovsub_lock *lsl;
108 struct cl_lock *parent = lck->lls_cl.cls_lock;
111 LASSERT(cl_lock_is_mutexed(parent));
112 LASSERT(cl_lock_is_mutexed(sublock));
115 lsl = cl2sub_lock(sublock);
117 * check that sub-lock doesn't have lock link to this top-lock.
119 LASSERT(lov_lock_link_find(env, lck, lsl) == NULL);
120 LASSERT(idx < lck->lls_nr);
122 lck->lls_sub[idx].sub_lock = lsl;
123 lck->lls_nr_filled++;
124 LASSERT(lck->lls_nr_filled <= lck->lls_nr);
125 cfs_list_add_tail(&link->lll_list, &lsl->lss_parents);
127 link->lll_super = lck;
129 lu_ref_add(&parent->cll_reference, "lov-child", sublock);
130 lck->lls_sub[idx].sub_flags |= LSF_HELD;
131 cl_lock_user_add(env, sublock);
133 rc = lov_sublock_modify(env, lck, lsl, &sublock->cll_descr, idx);
134 LASSERT(rc == 0); /* there is no way this can fail, currently */
138 static struct cl_lock *lov_sublock_alloc(const struct lu_env *env,
139 const struct cl_io *io,
140 struct lov_lock *lck,
141 int idx, struct lov_lock_link **out)
143 struct cl_lock *sublock;
144 struct cl_lock *parent;
145 struct lov_lock_link *link;
147 LASSERT(idx < lck->lls_nr);
150 OBD_SLAB_ALLOC_PTR_GFP(link, lov_lock_link_kmem, CFS_ALLOC_IO);
152 struct lov_sublock_env *subenv;
153 struct lov_lock_sub *lls;
154 struct cl_lock_descr *descr;
156 parent = lck->lls_cl.cls_lock;
157 lls = &lck->lls_sub[idx];
158 descr = &lls->sub_descr;
160 subenv = lov_sublock_env_get(env, parent, lls);
161 if (!IS_ERR(subenv)) {
162 /* CAVEAT: Don't try to add a field in lov_lock_sub
163 * to remember the subio. This is because lock is able
164 * to be cached, but this is not true for IO. This
165 * further means a sublock might be referenced in
166 * different io context. -jay */
168 sublock = cl_lock_hold(subenv->lse_env, subenv->lse_io,
169 descr, "lov-parent", parent);
170 lov_sublock_env_put(subenv);
173 sublock = (void*)subenv;
176 if (!IS_ERR(sublock))
179 OBD_SLAB_FREE_PTR(link, lov_lock_link_kmem);
181 sublock = ERR_PTR(-ENOMEM);
185 static void lov_sublock_unlock(const struct lu_env *env,
186 struct lovsub_lock *lsl,
187 struct cl_lock_closure *closure,
188 struct lov_sublock_env *subenv)
191 lov_sublock_env_put(subenv);
192 lsl->lss_active = NULL;
193 cl_lock_disclosure(env, closure);
197 static int lov_sublock_lock(const struct lu_env *env,
198 struct lov_lock *lck,
199 struct lov_lock_sub *lls,
200 struct cl_lock_closure *closure,
201 struct lov_sublock_env **lsep)
203 struct lovsub_lock *sublock;
204 struct cl_lock *child;
208 LASSERT(cfs_list_empty(&closure->clc_list));
210 sublock = lls->sub_lock;
211 child = sublock->lss_cl.cls_lock;
212 result = cl_lock_closure_build(env, child, closure);
214 struct cl_lock *parent = closure->clc_origin;
216 LASSERT(cl_lock_is_mutexed(child));
217 sublock->lss_active = parent;
219 if (unlikely((child->cll_state == CLS_FREEING) ||
220 (child->cll_flags & CLF_CANCELLED))) {
221 struct lov_lock_link *link;
223 * we could race with lock deletion which temporarily
224 * put the lock in freeing state, bug 19080.
226 LASSERT(!(lls->sub_flags & LSF_HELD));
228 link = lov_lock_link_find(env, lck, sublock);
229 LASSERT(link != NULL);
230 lov_lock_unlink(env, link, sublock);
231 lov_sublock_unlock(env, sublock, closure, NULL);
232 lck->lls_cancel_race = 1;
235 struct lov_sublock_env *subenv;
236 subenv = lov_sublock_env_get(env, parent, lls);
237 if (IS_ERR(subenv)) {
238 lov_sublock_unlock(env, sublock,
240 result = PTR_ERR(subenv);
250 * Updates the result of a top-lock operation from a result of sub-lock
251 * sub-operations. Top-operations like lov_lock_{enqueue,use,unuse}() iterate
252 * over sub-locks and lov_subresult() is used to calculate return value of a
253 * top-operation. To this end, possible return values of sub-operations are
257 * - CLO_WAIT wait for event
258 * - CLO_REPEAT repeat top-operation
259 * - -ne fundamental error
261 * Top-level return code can only go down through this list. CLO_REPEAT
262 * overwrites CLO_WAIT, because lock mutex was released and sleeping condition
263 * has to be rechecked by the upper layer.
265 static int lov_subresult(int result, int rc)
270 LASSERT(result <= 0 || result == CLO_REPEAT || result == CLO_WAIT);
271 LASSERT(rc <= 0 || rc == CLO_REPEAT || rc == CLO_WAIT);
272 CLASSERT(CLO_WAIT < CLO_REPEAT);
276 /* calculate ranks in the ordering above */
277 result_rank = result < 0 ? 1 + CLO_REPEAT : result;
278 rc_rank = rc < 0 ? 1 + CLO_REPEAT : rc;
280 if (result_rank < rc_rank)
286 * Creates sub-locks for a given lov_lock for the first time.
288 * Goes through all sub-objects of top-object, and creates sub-locks on every
289 * sub-object intersecting with top-lock extent. This is complicated by the
290 * fact that top-lock (that is being created) can be accessed concurrently
291 * through already created sub-locks (possibly shared with other top-locks).
293 static int lov_lock_sub_init(const struct lu_env *env,
294 struct lov_lock *lck, const struct cl_io *io)
304 struct lov_object *loo = cl2lov(lck->lls_cl.cls_obj);
305 struct lov_layout_raid0 *r0 = lov_r0(loo);
306 struct cl_lock *parent = lck->lls_cl.cls_lock;
310 lck->lls_orig = parent->cll_descr;
311 file_start = cl_offset(lov2cl(loo), parent->cll_descr.cld_start);
312 file_end = cl_offset(lov2cl(loo), parent->cll_descr.cld_end + 1) - 1;
314 for (i = 0, nr = 0; i < r0->lo_nr; i++) {
316 * XXX for wide striping smarter algorithm is desirable,
317 * breaking out of the loop, early.
319 if (lov_stripe_intersects(r0->lo_lsm, i,
320 file_start, file_end, &start, &end))
324 OBD_ALLOC(lck->lls_sub, nr * sizeof lck->lls_sub[0]);
325 if (lck->lls_sub == NULL)
330 * First, fill in sub-lock descriptions in
331 * lck->lls_sub[].sub_descr. They are used by lov_sublock_alloc()
332 * (called below in this function, and by lov_lock_enqueue()) to
333 * create sub-locks. At this moment, no other thread can access
336 for (i = 0, nr = 0; i < r0->lo_nr; ++i) {
337 if (lov_stripe_intersects(r0->lo_lsm, i,
338 file_start, file_end, &start, &end)) {
339 struct cl_lock_descr *descr;
341 descr = &lck->lls_sub[nr].sub_descr;
343 LASSERT(descr->cld_obj == NULL);
344 descr->cld_obj = lovsub2cl(r0->lo_sub[i]);
345 descr->cld_start = cl_index(descr->cld_obj, start);
346 descr->cld_end = cl_index(descr->cld_obj, end);
347 descr->cld_mode = parent->cll_descr.cld_mode;
348 descr->cld_gid = parent->cll_descr.cld_gid;
349 descr->cld_enq_flags = parent->cll_descr.cld_enq_flags;
350 /* XXX has no effect */
351 lck->lls_sub[nr].sub_got = *descr;
352 lck->lls_sub[nr].sub_stripe = i;
356 LASSERT(nr == lck->lls_nr);
358 * Then, create sub-locks. Once at least one sub-lock was created,
359 * top-lock can be reached by other threads.
361 for (i = 0; i < lck->lls_nr; ++i) {
362 struct cl_lock *sublock;
363 struct lov_lock_link *link;
365 if (lck->lls_sub[i].sub_lock == NULL) {
366 sublock = lov_sublock_alloc(env, io, lck, i, &link);
367 if (IS_ERR(sublock)) {
368 result = PTR_ERR(sublock);
371 cl_lock_get_trust(sublock);
372 cl_lock_mutex_get(env, sublock);
373 cl_lock_mutex_get(env, parent);
375 * recheck under mutex that sub-lock wasn't created
376 * concurrently, and that top-lock is still alive.
378 if (lck->lls_sub[i].sub_lock == NULL &&
379 parent->cll_state < CLS_FREEING) {
380 lov_sublock_adopt(env, lck, sublock, i, link);
381 cl_lock_mutex_put(env, parent);
383 OBD_SLAB_FREE_PTR(link, lov_lock_link_kmem);
384 cl_lock_mutex_put(env, parent);
385 cl_lock_unhold(env, sublock,
386 "lov-parent", parent);
388 cl_lock_mutex_put(env, sublock);
389 cl_lock_put(env, sublock);
393 * Some sub-locks can be missing at this point. This is not a problem,
394 * because enqueue will create them anyway. Main duty of this function
395 * is to fill in sub-lock descriptions in a race free manner.
400 static int lov_sublock_release(const struct lu_env *env, struct lov_lock *lck,
401 int i, int deluser, int rc)
403 struct cl_lock *parent = lck->lls_cl.cls_lock;
405 LASSERT(cl_lock_is_mutexed(parent));
408 if (lck->lls_sub[i].sub_flags & LSF_HELD) {
409 struct cl_lock *sublock;
412 LASSERT(lck->lls_sub[i].sub_lock != NULL);
413 sublock = lck->lls_sub[i].sub_lock->lss_cl.cls_lock;
414 LASSERT(cl_lock_is_mutexed(sublock));
416 lck->lls_sub[i].sub_flags &= ~LSF_HELD;
418 cl_lock_user_del(env, sublock);
420 * If the last hold is released, and cancellation is pending
421 * for a sub-lock, release parent mutex, to avoid keeping it
422 * while sub-lock is being paged out.
424 dying = (sublock->cll_descr.cld_mode == CLM_PHANTOM ||
425 sublock->cll_descr.cld_mode == CLM_GROUP ||
426 (sublock->cll_flags & (CLF_CANCELPEND|CLF_DOOMED))) &&
427 sublock->cll_holds == 1;
429 cl_lock_mutex_put(env, parent);
430 cl_lock_unhold(env, sublock, "lov-parent", parent);
432 cl_lock_mutex_get(env, parent);
433 rc = lov_subresult(rc, CLO_REPEAT);
436 * From now on lck->lls_sub[i].sub_lock is a "weak" pointer,
437 * not backed by a reference on a
438 * sub-lock. lovsub_lock_delete() will clear
439 * lck->lls_sub[i].sub_lock under semaphores, just before
440 * sub-lock is destroyed.
446 static void lov_sublock_hold(const struct lu_env *env, struct lov_lock *lck,
449 struct cl_lock *parent = lck->lls_cl.cls_lock;
451 LASSERT(cl_lock_is_mutexed(parent));
454 if (!(lck->lls_sub[i].sub_flags & LSF_HELD)) {
455 struct cl_lock *sublock;
457 LASSERT(lck->lls_sub[i].sub_lock != NULL);
458 sublock = lck->lls_sub[i].sub_lock->lss_cl.cls_lock;
459 LASSERT(cl_lock_is_mutexed(sublock));
460 LASSERT(sublock->cll_state != CLS_FREEING);
462 lck->lls_sub[i].sub_flags |= LSF_HELD;
464 cl_lock_get_trust(sublock);
465 cl_lock_hold_add(env, sublock, "lov-parent", parent);
466 cl_lock_user_add(env, sublock);
467 cl_lock_put(env, sublock);
472 static void lov_lock_fini(const struct lu_env *env,
473 struct cl_lock_slice *slice)
475 struct lov_lock *lck;
479 lck = cl2lov_lock(slice);
480 LASSERT(lck->lls_nr_filled == 0);
481 if (lck->lls_sub != NULL) {
482 for (i = 0; i < lck->lls_nr; ++i)
484 * No sub-locks exists at this point, as sub-lock has
485 * a reference on its parent.
487 LASSERT(lck->lls_sub[i].sub_lock == NULL);
488 OBD_FREE(lck->lls_sub, lck->lls_nr * sizeof lck->lls_sub[0]);
490 OBD_SLAB_FREE_PTR(lck, lov_lock_kmem);
496 * \retval 0 if state-transition can proceed
497 * \retval -ve otherwise.
499 static int lov_lock_enqueue_wait(const struct lu_env *env,
500 struct lov_lock *lck,
501 struct cl_lock *sublock)
503 struct cl_lock *lock = lck->lls_cl.cls_lock;
504 struct cl_lock *conflict = sublock->cll_conflict;
505 int result = CLO_REPEAT;
508 LASSERT(cl_lock_is_mutexed(lock));
509 LASSERT(cl_lock_is_mutexed(sublock));
510 LASSERT(sublock->cll_state == CLS_QUEUING);
511 LASSERT(conflict != NULL);
513 sublock->cll_conflict = NULL;
514 cl_lock_mutex_put(env, lock);
515 cl_lock_mutex_put(env, sublock);
517 LASSERT(cl_lock_nr_mutexed(env) == 0);
519 cl_lock_mutex_get(env, conflict);
520 cl_lock_cancel(env, conflict);
521 cl_lock_delete(env, conflict);
522 while (conflict->cll_state != CLS_FREEING) {
525 rc = cl_lock_state_wait(env, conflict);
529 result = lov_subresult(result, rc);
532 cl_lock_mutex_put(env, conflict);
533 lu_ref_del(&conflict->cll_reference, "cancel-wait", sublock);
534 cl_lock_put(env, conflict);
536 cl_lock_mutex_get(env, lock);
541 * Tries to advance a state machine of a given sub-lock toward enqueuing of
544 * \retval 0 if state-transition can proceed
545 * \retval -ve otherwise.
547 static int lov_lock_enqueue_one(const struct lu_env *env, struct lov_lock *lck,
548 struct cl_lock *sublock,
549 struct cl_io *io, __u32 enqflags, int last)
554 /* first, try to enqueue a sub-lock ... */
555 result = cl_enqueue_try(env, sublock, io, enqflags);
556 if (sublock->cll_state == CLS_ENQUEUED)
557 /* if it is enqueued, try to `wait' on it---maybe it's already
559 result = cl_wait_try(env, sublock);
561 * If CEF_ASYNC flag is set, then all sub-locks can be enqueued in
562 * parallel, otherwise---enqueue has to wait until sub-lock is granted
563 * before proceeding to the next one.
565 if (result == CLO_WAIT && sublock->cll_state <= CLS_HELD &&
566 enqflags & CEF_ASYNC && !last)
572 * Helper function for lov_lock_enqueue() that creates missing sub-lock.
574 static int lov_sublock_fill(const struct lu_env *env, struct cl_lock *parent,
575 struct cl_io *io, struct lov_lock *lck, int idx)
577 struct lov_lock_link *link;
578 struct cl_lock *sublock;
581 LASSERT(parent->cll_depth == 1);
582 cl_lock_mutex_put(env, parent);
583 sublock = lov_sublock_alloc(env, io, lck, idx, &link);
584 if (!IS_ERR(sublock))
585 cl_lock_mutex_get(env, sublock);
586 cl_lock_mutex_get(env, parent);
588 if (!IS_ERR(sublock)) {
589 cl_lock_get_trust(sublock);
590 if (parent->cll_state == CLS_QUEUING &&
591 lck->lls_sub[idx].sub_lock == NULL) {
592 lov_sublock_adopt(env, lck, sublock, idx, link);
594 OBD_SLAB_FREE_PTR(link, lov_lock_link_kmem);
595 /* other thread allocated sub-lock, or enqueue is no
597 cl_lock_mutex_put(env, parent);
598 cl_lock_unhold(env, sublock, "lov-parent", parent);
599 cl_lock_mutex_get(env, parent);
601 cl_lock_mutex_put(env, sublock);
602 cl_lock_put(env, sublock);
605 result = PTR_ERR(sublock);
610 * Implementation of cl_lock_operations::clo_enqueue() for lov layer. This
611 * function is rather subtle, as it enqueues top-lock (i.e., advances top-lock
612 * state machine from CLS_QUEUING to CLS_ENQUEUED states) by juggling sub-lock
613 * state machines in the face of sub-locks sharing (by multiple top-locks),
614 * and concurrent sub-lock cancellations.
616 static int lov_lock_enqueue(const struct lu_env *env,
617 const struct cl_lock_slice *slice,
618 struct cl_io *io, __u32 enqflags)
620 struct cl_lock *lock = slice->cls_lock;
621 struct lov_lock *lck = cl2lov_lock(slice);
622 struct cl_lock_closure *closure = lov_closure_get(env, lock);
625 enum cl_lock_state minstate;
629 for (result = 0, minstate = CLS_FREEING, i = 0; i < lck->lls_nr; ++i) {
631 struct lovsub_lock *sub;
632 struct lov_lock_sub *lls;
633 struct cl_lock *sublock;
634 struct lov_sublock_env *subenv;
636 if (lock->cll_state != CLS_QUEUING) {
638 * Lock might have left QUEUING state if previous
639 * iteration released its mutex. Stop enqueing in this
640 * case and let the upper layer to decide what to do.
642 LASSERT(i > 0 && result != 0);
646 lls = &lck->lls_sub[i];
649 * Sub-lock might have been canceled, while top-lock was
653 result = lov_sublock_fill(env, lock, io, lck, i);
654 /* lov_sublock_fill() released @lock mutex,
658 sublock = sub->lss_cl.cls_lock;
659 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
661 lov_sublock_hold(env, lck, i);
662 rc = lov_lock_enqueue_one(subenv->lse_env, lck, sublock,
663 subenv->lse_io, enqflags,
664 i == lck->lls_nr - 1);
665 minstate = min(minstate, sublock->cll_state);
666 if (rc == CLO_WAIT) {
667 switch (sublock->cll_state) {
669 /* take recursive mutex, the lock is
670 * released in lov_lock_enqueue_wait.
672 cl_lock_mutex_get(env, sublock);
673 lov_sublock_unlock(env, sub, closure,
675 rc = lov_lock_enqueue_wait(env, lck,
679 rc = lov_sublock_release(env, lck, i,
682 lov_sublock_unlock(env, sub, closure,
687 LASSERT(sublock->cll_conflict == NULL);
688 lov_sublock_unlock(env, sub, closure, subenv);
691 result = lov_subresult(result, rc);
695 cl_lock_closure_fini(closure);
696 RETURN(result ?: minstate >= CLS_ENQUEUED ? 0 : CLO_WAIT);
699 static int lov_lock_unuse(const struct lu_env *env,
700 const struct cl_lock_slice *slice)
702 struct lov_lock *lck = cl2lov_lock(slice);
703 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
709 for (result = 0, i = 0; i < lck->lls_nr; ++i) {
711 struct lovsub_lock *sub;
712 struct cl_lock *sublock;
713 struct lov_lock_sub *lls;
714 struct lov_sublock_env *subenv;
716 /* top-lock state cannot change concurrently, because single
717 * thread (one that released the last hold) carries unlocking
718 * to the completion. */
719 LASSERT(slice->cls_lock->cll_state == CLS_INTRANSIT);
720 lls = &lck->lls_sub[i];
725 sublock = sub->lss_cl.cls_lock;
726 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
728 if (lls->sub_flags & LSF_HELD) {
729 LASSERT(sublock->cll_state == CLS_HELD);
730 rc = cl_unuse_try(subenv->lse_env, sublock);
731 rc = lov_sublock_release(env, lck, i, 0, rc);
733 lov_sublock_unlock(env, sub, closure, subenv);
735 result = lov_subresult(result, rc);
738 if (result == 0 && lck->lls_cancel_race) {
739 lck->lls_cancel_race = 0;
742 cl_lock_closure_fini(closure);
747 static void lov_lock_cancel(const struct lu_env *env,
748 const struct cl_lock_slice *slice)
750 struct lov_lock *lck = cl2lov_lock(slice);
751 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
757 for (result = 0, i = 0; i < lck->lls_nr; ++i) {
759 struct lovsub_lock *sub;
760 struct cl_lock *sublock;
761 struct lov_lock_sub *lls;
762 struct lov_sublock_env *subenv;
764 /* top-lock state cannot change concurrently, because single
765 * thread (one that released the last hold) carries unlocking
766 * to the completion. */
767 lls = &lck->lls_sub[i];
772 sublock = sub->lss_cl.cls_lock;
773 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
775 if (!(lls->sub_flags & LSF_HELD)) {
776 lov_sublock_unlock(env, sub, closure, subenv);
780 switch(sublock->cll_state) {
782 rc = cl_unuse_try(subenv->lse_env,
784 lov_sublock_release(env, lck, i, 0, 0);
787 /* TODO: it's not a good idea to cancel this
788 * lock because it's innocent. But it's
789 * acceptable. The better way would be to
790 * define a new lock method to unhold the
792 cl_lock_cancel(env, sublock);
794 lov_sublock_release(env, lck, i, 1, 0);
797 lov_sublock_unlock(env, sub, closure, subenv);
800 if (rc == CLO_REPEAT) {
805 result = lov_subresult(result, rc);
809 CL_LOCK_DEBUG(D_ERROR, env, slice->cls_lock,
810 "lov_lock_cancel fails with %d.\n", result);
812 cl_lock_closure_fini(closure);
815 static int lov_lock_wait(const struct lu_env *env,
816 const struct cl_lock_slice *slice)
818 struct lov_lock *lck = cl2lov_lock(slice);
819 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
820 enum cl_lock_state minstate;
826 for (result = 0, minstate = CLS_FREEING, i = 0; i < lck->lls_nr; ++i) {
828 struct lovsub_lock *sub;
829 struct cl_lock *sublock;
830 struct lov_lock_sub *lls;
831 struct lov_sublock_env *subenv;
833 lls = &lck->lls_sub[i];
835 LASSERT(sub != NULL);
836 sublock = sub->lss_cl.cls_lock;
837 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
839 LASSERT(sublock->cll_state >= CLS_ENQUEUED);
840 if (sublock->cll_state < CLS_HELD)
841 rc = cl_wait_try(env, sublock);
843 minstate = min(minstate, sublock->cll_state);
844 lov_sublock_unlock(env, sub, closure, subenv);
846 result = lov_subresult(result, rc);
850 cl_lock_closure_fini(closure);
851 RETURN(result ?: minstate >= CLS_HELD ? 0 : CLO_WAIT);
854 static int lov_lock_use(const struct lu_env *env,
855 const struct cl_lock_slice *slice)
857 struct lov_lock *lck = cl2lov_lock(slice);
858 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
862 LASSERT(slice->cls_lock->cll_state == CLS_INTRANSIT);
865 for (result = 0, i = 0; i < lck->lls_nr; ++i) {
867 struct lovsub_lock *sub;
868 struct cl_lock *sublock;
869 struct lov_lock_sub *lls;
870 struct lov_sublock_env *subenv;
872 LASSERT(slice->cls_lock->cll_state == CLS_INTRANSIT);
874 lls = &lck->lls_sub[i];
878 * Sub-lock might have been canceled, while top-lock was
885 sublock = sub->lss_cl.cls_lock;
886 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
888 LASSERT(sublock->cll_state != CLS_FREEING);
889 lov_sublock_hold(env, lck, i);
890 if (sublock->cll_state == CLS_CACHED) {
891 rc = cl_use_try(subenv->lse_env, sublock, 0);
893 rc = lov_sublock_release(env, lck,
896 lov_sublock_unlock(env, sub, closure, subenv);
898 result = lov_subresult(result, rc);
903 if (lck->lls_cancel_race) {
905 * If there is unlocking happened at the same time, then
906 * sublock_lock state should be FREEING, and lov_sublock_lock
907 * should return CLO_REPEAT. In this case, it should return
908 * ESTALE, and up layer should reset the lock state to be NEW.
910 lck->lls_cancel_race = 0;
911 LASSERT(result != 0);
914 cl_lock_closure_fini(closure);
919 static int lock_lock_multi_match()
921 struct cl_lock *lock = slice->cls_lock;
922 struct cl_lock_descr *subneed = &lov_env_info(env)->lti_ldescr;
923 struct lov_object *loo = cl2lov(lov->lls_cl.cls_obj);
924 struct lov_layout_raid0 *r0 = lov_r0(loo);
925 struct lov_lock_sub *sub;
926 struct cl_object *subobj;
933 fstart = cl_offset(need->cld_obj, need->cld_start);
934 fend = cl_offset(need->cld_obj, need->cld_end + 1) - 1;
935 subneed->cld_mode = need->cld_mode;
936 cl_lock_mutex_get(env, lock);
937 for (i = 0; i < lov->lls_nr; ++i) {
938 sub = &lov->lls_sub[i];
939 if (sub->sub_lock == NULL)
941 subobj = sub->sub_descr.cld_obj;
942 if (!lov_stripe_intersects(r0->lo_lsm, sub->sub_stripe,
943 fstart, fend, &start, &end))
945 subneed->cld_start = cl_index(subobj, start);
946 subneed->cld_end = cl_index(subobj, end);
947 subneed->cld_obj = subobj;
948 if (!cl_lock_ext_match(&sub->sub_got, subneed)) {
953 cl_lock_mutex_put(env, lock);
958 * Check if the extent region \a descr is covered by \a child against the
959 * specific \a stripe.
961 static int lov_lock_stripe_is_matching(const struct lu_env *env,
962 struct lov_object *lov, int stripe,
963 const struct cl_lock_descr *child,
964 const struct cl_lock_descr *descr)
966 struct lov_stripe_md *lsm = lov_r0(lov)->lo_lsm;
971 if (lov_r0(lov)->lo_nr == 1)
972 return cl_lock_ext_match(child, descr);
975 * For a multi-stripes object:
976 * - make sure the descr only covers child's stripe, and
977 * - check if extent is matching.
979 start = cl_offset(&lov->lo_cl, descr->cld_start);
980 end = cl_offset(&lov->lo_cl, descr->cld_end + 1) - 1;
981 result = end - start <= lsm->lsm_stripe_size &&
982 stripe == lov_stripe_number(lsm, start) &&
983 stripe == lov_stripe_number(lsm, end);
985 struct cl_lock_descr *subd = &lov_env_info(env)->lti_ldescr;
989 subd->cld_obj = NULL; /* don't need sub object at all */
990 subd->cld_mode = descr->cld_mode;
991 subd->cld_gid = descr->cld_gid;
992 result = lov_stripe_intersects(lsm, stripe, start, end,
993 &sub_start, &sub_end);
995 subd->cld_start = cl_index(child->cld_obj, sub_start);
996 subd->cld_end = cl_index(child->cld_obj, sub_end);
997 result = cl_lock_ext_match(child, subd);
1003 * An implementation of cl_lock_operations::clo_fits_into() method.
1005 * Checks whether a lock (given by \a slice) is suitable for \a
1006 * io. Multi-stripe locks can be used only for "quick" io, like truncate, or
1009 * \see ccc_lock_fits_into().
1011 static int lov_lock_fits_into(const struct lu_env *env,
1012 const struct cl_lock_slice *slice,
1013 const struct cl_lock_descr *need,
1014 const struct cl_io *io)
1016 struct lov_lock *lov = cl2lov_lock(slice);
1017 struct lov_object *obj = cl2lov(slice->cls_obj);
1020 LASSERT(cl_object_same(need->cld_obj, slice->cls_obj));
1021 LASSERT(lov->lls_nr > 0);
1025 if (need->cld_mode == CLM_GROUP)
1027 * always allow to match group lock.
1029 result = cl_lock_ext_match(&lov->lls_orig, need);
1030 else if (lov->lls_nr == 1) {
1031 struct cl_lock_descr *got = &lov->lls_sub[0].sub_got;
1032 result = lov_lock_stripe_is_matching(env,
1033 cl2lov(slice->cls_obj),
1034 lov->lls_sub[0].sub_stripe,
1036 } else if (io->ci_type != CIT_SETATTR && io->ci_type != CIT_MISC &&
1037 !cl_io_is_append(io) && need->cld_mode != CLM_PHANTOM)
1039 * Multi-stripe locks are only suitable for `quick' IO and for
1045 * Most general case: multi-stripe existing lock, and
1046 * (potentially) multi-stripe @need lock. Check that @need is
1047 * covered by @lov's sub-locks.
1049 * For now, ignore lock expansions made by the server, and
1050 * match against original lock extent.
1052 result = cl_lock_ext_match(&lov->lls_orig, need);
1053 CDEBUG(D_DLMTRACE, DDESCR"/"DDESCR" %d %d/%d: %d\n",
1054 PDESCR(&lov->lls_orig), PDESCR(&lov->lls_sub[0].sub_got),
1055 lov->lls_sub[0].sub_stripe, lov->lls_nr, lov_r0(obj)->lo_nr,
1060 void lov_lock_unlink(const struct lu_env *env,
1061 struct lov_lock_link *link, struct lovsub_lock *sub)
1063 struct lov_lock *lck = link->lll_super;
1064 struct cl_lock *parent = lck->lls_cl.cls_lock;
1066 LASSERT(cl_lock_is_mutexed(parent));
1067 LASSERT(cl_lock_is_mutexed(sub->lss_cl.cls_lock));
1070 cfs_list_del_init(&link->lll_list);
1071 LASSERT(lck->lls_sub[link->lll_idx].sub_lock == sub);
1072 /* yank this sub-lock from parent's array */
1073 lck->lls_sub[link->lll_idx].sub_lock = NULL;
1074 LASSERT(lck->lls_nr_filled > 0);
1075 lck->lls_nr_filled--;
1076 lu_ref_del(&parent->cll_reference, "lov-child", sub->lss_cl.cls_lock);
1077 cl_lock_put(env, parent);
1078 OBD_SLAB_FREE_PTR(link, lov_lock_link_kmem);
1082 struct lov_lock_link *lov_lock_link_find(const struct lu_env *env,
1083 struct lov_lock *lck,
1084 struct lovsub_lock *sub)
1086 struct lov_lock_link *scan;
1088 LASSERT(cl_lock_is_mutexed(sub->lss_cl.cls_lock));
1091 cfs_list_for_each_entry(scan, &sub->lss_parents, lll_list) {
1092 if (scan->lll_super == lck)
1099 * An implementation of cl_lock_operations::clo_delete() method. This is
1100 * invoked for "top-to-bottom" delete, when lock destruction starts from the
1101 * top-lock, e.g., as a result of inode destruction.
1103 * Unlinks top-lock from all its sub-locks. Sub-locks are not deleted there:
1104 * this is done separately elsewhere:
1106 * - for inode destruction, lov_object_delete() calls cl_object_kill() for
1107 * each sub-object, purging its locks;
1109 * - in other cases (e.g., a fatal error with a top-lock) sub-locks are
1110 * left in the cache.
1112 static void lov_lock_delete(const struct lu_env *env,
1113 const struct cl_lock_slice *slice)
1115 struct lov_lock *lck = cl2lov_lock(slice);
1116 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
1117 struct lov_lock_link *link;
1121 LASSERT(slice->cls_lock->cll_state == CLS_FREEING);
1124 for (i = 0; i < lck->lls_nr; ++i) {
1125 struct lov_lock_sub *lls = &lck->lls_sub[i];
1126 struct lovsub_lock *lsl = lls->sub_lock;
1128 if (lsl == NULL) /* already removed */
1131 rc = lov_sublock_lock(env, lck, lls, closure, NULL);
1132 if (rc == CLO_REPEAT) {
1138 LASSERT(lsl->lss_cl.cls_lock->cll_state < CLS_FREEING);
1140 if (lls->sub_flags & LSF_HELD)
1141 lov_sublock_release(env, lck, i, 1, 0);
1143 link = lov_lock_link_find(env, lck, lsl);
1144 LASSERT(link != NULL);
1145 lov_lock_unlink(env, link, lsl);
1146 LASSERT(lck->lls_sub[i].sub_lock == NULL);
1148 lov_sublock_unlock(env, lsl, closure, NULL);
1151 cl_lock_closure_fini(closure);
1155 static int lov_lock_print(const struct lu_env *env, void *cookie,
1156 lu_printer_t p, const struct cl_lock_slice *slice)
1158 struct lov_lock *lck = cl2lov_lock(slice);
1161 (*p)(env, cookie, "%d\n", lck->lls_nr);
1162 for (i = 0; i < lck->lls_nr; ++i) {
1163 struct lov_lock_sub *sub;
1165 sub = &lck->lls_sub[i];
1166 (*p)(env, cookie, " %d %x: ", i, sub->sub_flags);
1167 if (sub->sub_lock != NULL)
1168 cl_lock_print(env, cookie, p,
1169 sub->sub_lock->lss_cl.cls_lock);
1171 (*p)(env, cookie, "---\n");
1176 static const struct cl_lock_operations lov_lock_ops = {
1177 .clo_fini = lov_lock_fini,
1178 .clo_enqueue = lov_lock_enqueue,
1179 .clo_wait = lov_lock_wait,
1180 .clo_use = lov_lock_use,
1181 .clo_unuse = lov_lock_unuse,
1182 .clo_cancel = lov_lock_cancel,
1183 .clo_fits_into = lov_lock_fits_into,
1184 .clo_delete = lov_lock_delete,
1185 .clo_print = lov_lock_print
1188 int lov_lock_init_raid0(const struct lu_env *env, struct cl_object *obj,
1189 struct cl_lock *lock, const struct cl_io *io)
1191 struct lov_lock *lck;
1195 OBD_SLAB_ALLOC_PTR_GFP(lck, lov_lock_kmem, CFS_ALLOC_IO);
1197 cl_lock_slice_add(lock, &lck->lls_cl, obj, &lov_lock_ops);
1198 result = lov_lock_sub_init(env, lck, io);
1204 static struct cl_lock_closure *lov_closure_get(const struct lu_env *env,
1205 struct cl_lock *parent)
1207 struct cl_lock_closure *closure;
1209 closure = &lov_env_info(env)->lti_closure;
1210 LASSERT(cfs_list_empty(&closure->clc_list));
1211 cl_lock_closure_init(env, closure, parent, 1);