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,
10 * as published by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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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19 * version 2 along with this program; If not, see
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 2008 Sun Microsystems, Inc. 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"
45 /** \addtogroup lov lov @{ */
47 static struct cl_lock_closure *lov_closure_get(const struct lu_env *env,
48 struct cl_lock *parent);
50 /*****************************************************************************
52 * Lov lock operations.
56 static struct lov_sublock_env *lov_sublock_env_get(const struct lu_env *env,
57 struct cl_lock *parent,
58 struct lov_lock_sub *lls)
60 struct lov_sublock_env *subenv;
61 struct lov_io *lio = lov_env_io(env);
62 struct cl_io *io = lio->lis_cl.cis_io;
63 struct lov_io_sub *sub;
65 subenv = &lov_env_session(env)->ls_subenv;
68 * FIXME: We tend to use the subio's env & io to call the sublock
69 * lock operations because osc lock sometimes stores some control
70 * variables in thread's IO infomation(Now only lockless information).
71 * However, if the lock's host(object) is different from the object
72 * for current IO, we have no way to get the subenv and subio because
73 * they are not initialized at all. As a temp fix, in this case,
74 * we still borrow the parent's env to call sublock operations.
76 if (!cl_object_same(io->ci_obj, parent->cll_descr.cld_obj)) {
77 subenv->lse_env = env;
79 subenv->lse_sub = NULL;
82 sub = lov_sub_get(env, lio, lls->sub_stripe);
84 subenv->lse_env = sub->sub_env;
85 subenv->lse_io = sub->sub_io;
86 subenv->lse_sub = sub;
94 static void lov_sublock_env_put(struct lov_sublock_env *subenv)
96 if (subenv && subenv->lse_sub)
97 lov_sub_put(subenv->lse_sub);
100 static void lov_sublock_adopt(const struct lu_env *env, struct lov_lock *lck,
101 struct cl_lock *sublock, int idx,
102 struct lov_lock_link *link)
104 struct lovsub_lock *lsl;
105 struct cl_lock *parent = lck->lls_cl.cls_lock;
108 LASSERT(cl_lock_is_mutexed(parent));
109 LASSERT(cl_lock_is_mutexed(sublock));
112 lsl = cl2sub_lock(sublock);
114 * check that sub-lock doesn't have lock link to this top-lock.
116 LASSERT(lov_lock_link_find(env, lck, lsl) == NULL);
117 LASSERT(idx < lck->lls_nr);
119 lck->lls_sub[idx].sub_lock = lsl;
120 lck->lls_nr_filled++;
121 LASSERT(lck->lls_nr_filled <= lck->lls_nr);
122 list_add_tail(&link->lll_list, &lsl->lss_parents);
124 link->lll_super = lck;
126 lu_ref_add(&parent->cll_reference, "lov-child", sublock);
127 lck->lls_sub[idx].sub_flags |= LSF_HELD;
128 cl_lock_user_add(env, sublock);
130 rc = lov_sublock_modify(env, lck, lsl, &sublock->cll_descr, idx);
131 LASSERT(rc == 0); /* there is no way this can fail, currently */
135 static struct cl_lock *lov_sublock_alloc(const struct lu_env *env,
136 const struct cl_io *io,
137 struct lov_lock *lck,
138 int idx, struct lov_lock_link **out)
140 struct cl_lock *sublock;
141 struct cl_lock *parent;
142 struct lov_lock_link *link;
144 LASSERT(idx < lck->lls_nr);
147 OBD_SLAB_ALLOC_PTR_GFP(link, lov_lock_link_kmem, CFS_ALLOC_IO);
149 struct lov_sublock_env *subenv;
150 struct lov_lock_sub *lls;
151 struct cl_lock_descr *descr;
153 parent = lck->lls_cl.cls_lock;
154 lls = &lck->lls_sub[idx];
155 descr = &lls->sub_descr;
157 subenv = lov_sublock_env_get(env, parent, lls);
158 if (!IS_ERR(subenv)) {
159 /* CAVEAT: Don't try to add a field in lov_lock_sub
160 * to remember the subio. This is because lock is able
161 * to be cached, but this is not true for IO. This
162 * further means a sublock might be referenced in
163 * different io context. -jay */
165 sublock = cl_lock_hold(subenv->lse_env, subenv->lse_io,
166 descr, "lov-parent", parent);
167 lov_sublock_env_put(subenv);
170 sublock = (void*)subenv;
173 if (!IS_ERR(sublock))
176 OBD_SLAB_FREE_PTR(link, lov_lock_link_kmem);
178 sublock = ERR_PTR(-ENOMEM);
182 static void lov_sublock_unlock(const struct lu_env *env,
183 struct lovsub_lock *lsl,
184 struct cl_lock_closure *closure,
185 struct lov_sublock_env *subenv)
188 lov_sublock_env_put(subenv);
189 lsl->lss_active = NULL;
190 cl_lock_disclosure(env, closure);
194 static int lov_sublock_lock(const struct lu_env *env,
195 struct lov_lock *lck,
196 struct lov_lock_sub *lls,
197 struct cl_lock_closure *closure,
198 struct lov_sublock_env **lsep)
200 struct lovsub_lock *sublock;
201 struct cl_lock *child;
205 LASSERT(list_empty(&closure->clc_list));
207 sublock = lls->sub_lock;
208 child = sublock->lss_cl.cls_lock;
209 result = cl_lock_closure_build(env, child, closure);
211 struct cl_lock *parent = closure->clc_origin;
213 LASSERT(cl_lock_is_mutexed(child));
214 sublock->lss_active = parent;
216 if (unlikely(child->cll_state == CLS_FREEING)) {
217 struct lov_lock_link *link;
219 * we could race with lock deletion which temporarily
220 * put the lock in freeing state, bug 19080.
222 LASSERT(!(lls->sub_flags & LSF_HELD));
224 link = lov_lock_link_find(env, lck, sublock);
225 LASSERT(link != NULL);
226 lov_lock_unlink(env, link, sublock);
227 lov_sublock_unlock(env, sublock, closure, NULL);
230 struct lov_sublock_env *subenv;
231 subenv = lov_sublock_env_get(env, parent, lls);
232 if (IS_ERR(subenv)) {
233 lov_sublock_unlock(env, sublock,
235 result = PTR_ERR(subenv);
245 * Updates the result of a top-lock operation from a result of sub-lock
246 * sub-operations. Top-operations like lov_lock_{enqueue,use,unuse}() iterate
247 * over sub-locks and lov_subresult() is used to calculate return value of a
248 * top-operation. To this end, possible return values of sub-operations are
252 * - CLO_WAIT wait for event
253 * - CLO_REPEAT repeat top-operation
254 * - -ne fundamental error
256 * Top-level return code can only go down through this list. CLO_REPEAT
257 * overwrites CLO_WAIT, because lock mutex was released and sleeping condition
258 * has to be rechecked by the upper layer.
260 static int lov_subresult(int result, int rc)
265 LASSERT(result <= 0 || result == CLO_REPEAT || result == CLO_WAIT);
266 LASSERT(rc <= 0 || rc == CLO_REPEAT || rc == CLO_WAIT);
267 CLASSERT(CLO_WAIT < CLO_REPEAT);
271 /* calculate ranks in the ordering above */
272 result_rank = result < 0 ? 1 + CLO_REPEAT : result;
273 rc_rank = rc < 0 ? 1 + CLO_REPEAT : rc;
275 if (result_rank < rc_rank)
281 * Creates sub-locks for a given lov_lock for the first time.
283 * Goes through all sub-objects of top-object, and creates sub-locks on every
284 * sub-object intersecting with top-lock extent. This is complicated by the
285 * fact that top-lock (that is being created) can be accessed concurrently
286 * through already created sub-locks (possibly shared with other top-locks).
288 static int lov_lock_sub_init(const struct lu_env *env,
289 struct lov_lock *lck, const struct cl_io *io)
302 struct lov_object *loo = cl2lov(lck->lls_cl.cls_obj);
303 struct lov_layout_raid0 *r0 = lov_r0(loo);
304 struct cl_lock *parent = lck->lls_cl.cls_lock;
308 lck->lls_orig = parent->cll_descr;
309 file_start = cl_offset(lov2cl(loo), parent->cll_descr.cld_start);
310 file_end = cl_offset(lov2cl(loo), parent->cll_descr.cld_end + 1) - 1;
312 start_stripe = lov_stripe_number(r0->lo_lsm, file_start);
313 for (i = 0, nr = 0; i < r0->lo_nr; i++) {
315 * XXX for wide striping smarter algorithm is desirable,
316 * breaking out of the loop, early.
318 stripe = (start_stripe + i) % r0->lo_nr;
319 if (lov_stripe_intersects(r0->lo_lsm, stripe,
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 (j = 0, nr = 0; j < i; ++j) {
337 stripe = (start_stripe + j) % r0->lo_nr;
338 if (lov_stripe_intersects(r0->lo_lsm, stripe,
339 file_start, file_end, &start, &end)) {
340 struct cl_lock_descr *descr;
342 descr = &lck->lls_sub[nr].sub_descr;
344 LASSERT(descr->cld_obj == NULL);
345 descr->cld_obj = lovsub2cl(r0->lo_sub[stripe]);
346 descr->cld_start = cl_index(descr->cld_obj, start);
347 descr->cld_end = cl_index(descr->cld_obj, end);
348 descr->cld_mode = parent->cll_descr.cld_mode;
349 descr->cld_gid = parent->cll_descr.cld_gid;
350 /* XXX has no effect */
351 lck->lls_sub[nr].sub_got = *descr;
352 lck->lls_sub[nr].sub_stripe = stripe;
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_mutex_get(env, sublock);
372 cl_lock_mutex_get(env, parent);
374 * recheck under mutex that sub-lock wasn't created
375 * concurrently, and that top-lock is still alive.
377 if (lck->lls_sub[i].sub_lock == NULL &&
378 parent->cll_state < CLS_FREEING) {
379 lov_sublock_adopt(env, lck, sublock, i, link);
380 cl_lock_mutex_put(env, parent);
382 OBD_SLAB_FREE_PTR(link, lov_lock_link_kmem);
383 cl_lock_mutex_put(env, parent);
384 cl_lock_unhold(env, sublock,
385 "lov-parent", parent);
387 cl_lock_mutex_put(env, sublock);
391 * Some sub-locks can be missing at this point. This is not a problem,
392 * because enqueue will create them anyway. Main duty of this function
393 * is to fill in sub-lock descriptions in a race free manner.
398 static int lov_sublock_release(const struct lu_env *env, struct lov_lock *lck,
399 int i, int deluser, int rc)
401 struct cl_lock *parent = lck->lls_cl.cls_lock;
403 LASSERT(cl_lock_is_mutexed(parent));
406 if (lck->lls_sub[i].sub_flags & LSF_HELD) {
407 struct cl_lock *sublock;
410 LASSERT(lck->lls_sub[i].sub_lock != NULL);
411 sublock = lck->lls_sub[i].sub_lock->lss_cl.cls_lock;
412 LASSERT(cl_lock_is_mutexed(sublock));
414 lck->lls_sub[i].sub_flags &= ~LSF_HELD;
416 cl_lock_user_del(env, sublock);
418 * If the last hold is released, and cancellation is pending
419 * for a sub-lock, release parent mutex, to avoid keeping it
420 * while sub-lock is being paged out.
422 dying = (sublock->cll_descr.cld_mode == CLM_PHANTOM ||
423 sublock->cll_descr.cld_mode == CLM_GROUP ||
424 (sublock->cll_flags & (CLF_CANCELPEND|CLF_DOOMED))) &&
425 sublock->cll_holds == 1;
427 cl_lock_mutex_put(env, parent);
428 cl_lock_unhold(env, sublock, "lov-parent", parent);
430 cl_lock_mutex_get(env, parent);
431 rc = lov_subresult(rc, CLO_REPEAT);
434 * From now on lck->lls_sub[i].sub_lock is a "weak" pointer,
435 * not backed by a reference on a
436 * sub-lock. lovsub_lock_delete() will clear
437 * lck->lls_sub[i].sub_lock under semaphores, just before
438 * sub-lock is destroyed.
444 static void lov_sublock_hold(const struct lu_env *env, struct lov_lock *lck,
447 struct cl_lock *parent = lck->lls_cl.cls_lock;
449 LASSERT(cl_lock_is_mutexed(parent));
452 if (!(lck->lls_sub[i].sub_flags & LSF_HELD)) {
453 struct cl_lock *sublock;
455 LASSERT(lck->lls_sub[i].sub_lock != NULL);
456 sublock = lck->lls_sub[i].sub_lock->lss_cl.cls_lock;
457 LASSERT(cl_lock_is_mutexed(sublock));
458 LASSERT(sublock->cll_state != CLS_FREEING);
460 lck->lls_sub[i].sub_flags |= LSF_HELD;
462 cl_lock_get_trust(sublock);
463 cl_lock_hold_add(env, sublock, "lov-parent", parent);
464 cl_lock_user_add(env, sublock);
465 cl_lock_put(env, sublock);
470 static void lov_lock_fini(const struct lu_env *env,
471 struct cl_lock_slice *slice)
473 struct lov_lock *lck;
477 lck = cl2lov_lock(slice);
478 LASSERT(lck->lls_nr_filled == 0);
479 if (lck->lls_sub != NULL) {
480 for (i = 0; i < lck->lls_nr; ++i)
482 * No sub-locks exists at this point, as sub-lock has
483 * a reference on its parent.
485 LASSERT(lck->lls_sub[i].sub_lock == NULL);
486 OBD_FREE(lck->lls_sub, lck->lls_nr * sizeof lck->lls_sub[0]);
488 OBD_SLAB_FREE_PTR(lck, lov_lock_kmem);
493 * Tries to advance a state machine of a given sub-lock toward enqueuing of
496 * \retval 0 if state-transition can proceed
497 * \retval -ve otherwise.
499 static int lov_lock_enqueue_one(const struct lu_env *env, struct lov_lock *lck,
500 struct cl_lock *sublock,
501 struct cl_io *io, __u32 enqflags, int last)
506 /* first, try to enqueue a sub-lock ... */
507 result = cl_enqueue_try(env, sublock, io, enqflags);
508 if (sublock->cll_state == CLS_ENQUEUED)
509 /* if it is enqueued, try to `wait' on it---maybe it's already
511 result = cl_wait_try(env, sublock);
513 * If CEF_ASYNC flag is set, then all sub-locks can be enqueued in
514 * parallel, otherwise---enqueue has to wait until sub-lock is granted
515 * before proceeding to the next one.
517 if (result == CLO_WAIT && sublock->cll_state <= CLS_HELD &&
518 enqflags & CEF_ASYNC && !last)
524 * Helper function for lov_lock_enqueue() that creates missing sub-lock.
526 static int lov_sublock_fill(const struct lu_env *env, struct cl_lock *parent,
527 struct cl_io *io, struct lov_lock *lck, int idx)
529 struct lov_lock_link *link;
530 struct cl_lock *sublock;
533 LASSERT(parent->cll_depth == 1);
534 cl_lock_mutex_put(env, parent);
535 sublock = lov_sublock_alloc(env, io, lck, idx, &link);
536 if (!IS_ERR(sublock))
537 cl_lock_mutex_get(env, sublock);
538 cl_lock_mutex_get(env, parent);
540 if (!IS_ERR(sublock)) {
541 if (parent->cll_state == CLS_QUEUING &&
542 lck->lls_sub[idx].sub_lock == NULL)
543 lov_sublock_adopt(env, lck, sublock, idx, link);
545 OBD_SLAB_FREE_PTR(link, lov_lock_link_kmem);
546 /* other thread allocated sub-lock, or enqueue is no
548 cl_lock_mutex_put(env, parent);
549 cl_lock_unhold(env, sublock, "lov-parent", parent);
550 cl_lock_mutex_get(env, parent);
552 cl_lock_mutex_put(env, sublock);
555 result = PTR_ERR(sublock);
560 * Implementation of cl_lock_operations::clo_enqueue() for lov layer. This
561 * function is rather subtle, as it enqueues top-lock (i.e., advances top-lock
562 * state machine from CLS_QUEUING to CLS_ENQUEUED states) by juggling sub-lock
563 * state machines in the face of sub-locks sharing (by multiple top-locks),
564 * and concurrent sub-lock cancellations.
566 static int lov_lock_enqueue(const struct lu_env *env,
567 const struct cl_lock_slice *slice,
568 struct cl_io *io, __u32 enqflags)
570 struct cl_lock *lock = slice->cls_lock;
571 struct lov_lock *lck = cl2lov_lock(slice);
572 struct cl_lock_closure *closure = lov_closure_get(env, lock);
575 enum cl_lock_state minstate;
579 for (result = 0, minstate = CLS_FREEING, i = 0; i < lck->lls_nr; ++i) {
581 struct lovsub_lock *sub;
582 struct lov_lock_sub *lls;
583 struct cl_lock *sublock;
584 struct lov_sublock_env *subenv;
586 if (lock->cll_state != CLS_QUEUING) {
588 * Lock might have left QUEUING state if previous
589 * iteration released its mutex. Stop enqueing in this
590 * case and let the upper layer to decide what to do.
592 LASSERT(i > 0 && result != 0);
596 lls = &lck->lls_sub[i];
599 * Sub-lock might have been canceled, while top-lock was
603 result = lov_sublock_fill(env, lock, io, lck, i);
604 /* lov_sublock_fill() released @lock mutex,
608 sublock = sub->lss_cl.cls_lock;
609 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
611 lov_sublock_hold(env, lck, i);
612 rc = lov_lock_enqueue_one(subenv->lse_env, lck, sublock,
613 subenv->lse_io, enqflags,
614 i == lck->lls_nr - 1);
615 minstate = min(minstate, sublock->cll_state);
617 * Don't hold a sub-lock in CLS_CACHED state, see
618 * description for lov_lock::lls_sub.
620 if (sublock->cll_state > CLS_HELD)
621 rc = lov_sublock_release(env, lck, i, 1, rc);
622 lov_sublock_unlock(env, sub, closure, subenv);
624 result = lov_subresult(result, rc);
628 cl_lock_closure_fini(closure);
629 RETURN(result ?: minstate >= CLS_ENQUEUED ? 0 : CLO_WAIT);
632 static int lov_lock_unuse(const struct lu_env *env,
633 const struct cl_lock_slice *slice)
635 struct lov_lock *lck = cl2lov_lock(slice);
636 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
642 for (result = 0, i = 0; i < lck->lls_nr; ++i) {
644 struct lovsub_lock *sub;
645 struct cl_lock *sublock;
646 struct lov_lock_sub *lls;
647 struct lov_sublock_env *subenv;
649 /* top-lock state cannot change concurrently, because single
650 * thread (one that released the last hold) carries unlocking
651 * to the completion. */
652 LASSERT(slice->cls_lock->cll_state == CLS_UNLOCKING);
653 lls = &lck->lls_sub[i];
658 sublock = sub->lss_cl.cls_lock;
659 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
661 if (lck->lls_sub[i].sub_flags & LSF_HELD) {
662 LASSERT(sublock->cll_state == CLS_HELD);
663 rc = cl_unuse_try(subenv->lse_env, sublock);
665 rc = lov_sublock_release(env, lck,
668 lov_sublock_unlock(env, sub, closure, subenv);
670 result = lov_subresult(result, rc);
674 if (result == 0 && lck->lls_unuse_race) {
675 lck->lls_unuse_race = 0;
678 cl_lock_closure_fini(closure);
682 static int lov_lock_wait(const struct lu_env *env,
683 const struct cl_lock_slice *slice)
685 struct lov_lock *lck = cl2lov_lock(slice);
686 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
687 enum cl_lock_state minstate;
693 for (result = 0, minstate = CLS_FREEING, i = 0; i < lck->lls_nr; ++i) {
695 struct lovsub_lock *sub;
696 struct cl_lock *sublock;
697 struct lov_lock_sub *lls;
698 struct lov_sublock_env *subenv;
700 lls = &lck->lls_sub[i];
702 LASSERT(sub != NULL);
703 sublock = sub->lss_cl.cls_lock;
704 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
706 LASSERT(sublock->cll_state >= CLS_ENQUEUED);
707 if (sublock->cll_state < CLS_HELD)
708 rc = cl_wait_try(env, sublock);
710 minstate = min(minstate, sublock->cll_state);
711 lov_sublock_unlock(env, sub, closure, subenv);
713 result = lov_subresult(result, rc);
717 cl_lock_closure_fini(closure);
718 RETURN(result ?: minstate >= CLS_HELD ? 0 : CLO_WAIT);
721 static int lov_lock_use(const struct lu_env *env,
722 const struct cl_lock_slice *slice)
724 struct lov_lock *lck = cl2lov_lock(slice);
725 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
729 LASSERT(slice->cls_lock->cll_state == CLS_CACHED);
732 for (result = 0, i = 0; i < lck->lls_nr; ++i) {
734 struct lovsub_lock *sub;
735 struct cl_lock *sublock;
736 struct lov_lock_sub *lls;
737 struct lov_sublock_env *subenv;
739 if (slice->cls_lock->cll_state != CLS_CACHED) {
740 /* see comment in lov_lock_enqueue(). */
741 LASSERT(i > 0 && result != 0);
745 * if a sub-lock was destroyed while top-lock was in
746 * CLS_CACHED state, top-lock would have been moved into
747 * CLS_NEW state, so all sub-locks have to be in place.
749 lls = &lck->lls_sub[i];
751 LASSERT(sub != NULL);
752 sublock = sub->lss_cl.cls_lock;
753 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
755 LASSERT(sublock->cll_state != CLS_FREEING);
756 lov_sublock_hold(env, lck, i);
757 if (sublock->cll_state == CLS_CACHED) {
758 rc = cl_use_try(subenv->lse_env, sublock);
760 rc = lov_sublock_release(env, lck,
764 lov_sublock_unlock(env, sub, closure, subenv);
766 result = lov_subresult(result, rc);
770 cl_lock_closure_fini(closure);
775 static int lock_lock_multi_match()
777 struct cl_lock *lock = slice->cls_lock;
778 struct cl_lock_descr *subneed = &lov_env_info(env)->lti_ldescr;
779 struct lov_object *loo = cl2lov(lov->lls_cl.cls_obj);
780 struct lov_layout_raid0 *r0 = lov_r0(loo);
781 struct lov_lock_sub *sub;
782 struct cl_object *subobj;
789 fstart = cl_offset(need->cld_obj, need->cld_start);
790 fend = cl_offset(need->cld_obj, need->cld_end + 1) - 1;
791 subneed->cld_mode = need->cld_mode;
792 cl_lock_mutex_get(env, lock);
793 for (i = 0; i < lov->lls_nr; ++i) {
794 sub = &lov->lls_sub[i];
795 if (sub->sub_lock == NULL)
797 subobj = sub->sub_descr.cld_obj;
798 if (!lov_stripe_intersects(r0->lo_lsm, sub->sub_stripe,
799 fstart, fend, &start, &end))
801 subneed->cld_start = cl_index(subobj, start);
802 subneed->cld_end = cl_index(subobj, end);
803 subneed->cld_obj = subobj;
804 if (!cl_lock_ext_match(&sub->sub_got, subneed)) {
809 cl_lock_mutex_put(env, lock);
814 * Check if the extent region \a descr is covered by \a child against the
815 * specific \a stripe.
817 static int lov_lock_stripe_is_matching(const struct lu_env *env,
818 struct lov_object *lov, int stripe,
819 const struct cl_lock_descr *child,
820 const struct cl_lock_descr *descr)
822 struct lov_stripe_md *lsm = lov_r0(lov)->lo_lsm;
827 if (lov_r0(lov)->lo_nr == 1)
828 return cl_lock_ext_match(child, descr);
831 * For a multi-stripes object:
832 * - make sure the descr only covers child's stripe, and
833 * - check if extent is matching.
835 start = cl_offset(&lov->lo_cl, descr->cld_start);
836 end = cl_offset(&lov->lo_cl, descr->cld_end + 1) - 1;
837 result = end - start <= lsm->lsm_stripe_size &&
838 stripe == lov_stripe_number(lsm, start) &&
839 stripe == lov_stripe_number(lsm, end);
841 struct cl_lock_descr *subd = &lov_env_info(env)->lti_ldescr;
845 subd->cld_obj = NULL; /* don't need sub object at all */
846 subd->cld_mode = descr->cld_mode;
847 subd->cld_gid = descr->cld_gid;
848 result = lov_stripe_intersects(lsm, stripe, start, end,
849 &sub_start, &sub_end);
851 subd->cld_start = cl_index(child->cld_obj, sub_start);
852 subd->cld_end = cl_index(child->cld_obj, sub_end);
853 result = cl_lock_ext_match(child, subd);
859 * An implementation of cl_lock_operations::clo_fits_into() method.
861 * Checks whether a lock (given by \a slice) is suitable for \a
862 * io. Multi-stripe locks can be used only for "quick" io, like truncate, or
865 * \see ccc_lock_fits_into().
867 static int lov_lock_fits_into(const struct lu_env *env,
868 const struct cl_lock_slice *slice,
869 const struct cl_lock_descr *need,
870 const struct cl_io *io)
872 struct lov_lock *lov = cl2lov_lock(slice);
873 struct lov_object *obj = cl2lov(slice->cls_obj);
876 LASSERT(cl_object_same(need->cld_obj, slice->cls_obj));
877 LASSERT(lov->lls_nr > 0);
881 if (need->cld_mode == CLM_GROUP)
883 * always allow to match group lock.
885 result = cl_lock_ext_match(&lov->lls_orig, need);
886 else if (lov->lls_nr == 1) {
887 struct cl_lock_descr *got = &lov->lls_sub[0].sub_got;
888 result = lov_lock_stripe_is_matching(env,
889 cl2lov(slice->cls_obj),
890 lov->lls_sub[0].sub_stripe,
892 } else if (io->ci_type != CIT_TRUNC && io->ci_type != CIT_MISC &&
893 !cl_io_is_append(io) && need->cld_mode != CLM_PHANTOM)
895 * Multi-stripe locks are only suitable for `quick' IO and for
901 * Most general case: multi-stripe existing lock, and
902 * (potentially) multi-stripe @need lock. Check that @need is
903 * covered by @lov's sub-locks.
905 * For now, ignore lock expansions made by the server, and
906 * match against original lock extent.
908 result = cl_lock_ext_match(&lov->lls_orig, need);
909 CDEBUG(D_DLMTRACE, DDESCR"/"DDESCR" %i %i/%i: %i\n",
910 PDESCR(&lov->lls_orig), PDESCR(&lov->lls_sub[0].sub_got),
911 lov->lls_sub[0].sub_stripe, lov->lls_nr, lov_r0(obj)->lo_nr,
916 void lov_lock_unlink(const struct lu_env *env,
917 struct lov_lock_link *link, struct lovsub_lock *sub)
919 struct lov_lock *lck = link->lll_super;
920 struct cl_lock *parent = lck->lls_cl.cls_lock;
922 LASSERT(cl_lock_is_mutexed(parent));
923 LASSERT(cl_lock_is_mutexed(sub->lss_cl.cls_lock));
926 list_del_init(&link->lll_list);
927 LASSERT(lck->lls_sub[link->lll_idx].sub_lock == sub);
928 /* yank this sub-lock from parent's array */
929 lck->lls_sub[link->lll_idx].sub_lock = NULL;
930 LASSERT(lck->lls_nr_filled > 0);
931 lck->lls_nr_filled--;
932 lu_ref_del(&parent->cll_reference, "lov-child", sub->lss_cl.cls_lock);
933 cl_lock_put(env, parent);
934 OBD_SLAB_FREE_PTR(link, lov_lock_link_kmem);
938 struct lov_lock_link *lov_lock_link_find(const struct lu_env *env,
939 struct lov_lock *lck,
940 struct lovsub_lock *sub)
942 struct lov_lock_link *scan;
944 LASSERT(cl_lock_is_mutexed(sub->lss_cl.cls_lock));
947 list_for_each_entry(scan, &sub->lss_parents, lll_list) {
948 if (scan->lll_super == lck)
955 * An implementation of cl_lock_operations::clo_delete() method. This is
956 * invoked for "top-to-bottom" delete, when lock destruction starts from the
957 * top-lock, e.g., as a result of inode destruction.
959 * Unlinks top-lock from all its sub-locks. Sub-locks are not deleted there:
960 * this is done separately elsewhere:
962 * - for inode destruction, lov_object_delete() calls cl_object_kill() for
963 * each sub-object, purging its locks;
965 * - in other cases (e.g., a fatal error with a top-lock) sub-locks are
968 static void lov_lock_delete(const struct lu_env *env,
969 const struct cl_lock_slice *slice)
971 struct lov_lock *lck = cl2lov_lock(slice);
972 struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
975 LASSERT(slice->cls_lock->cll_state == CLS_FREEING);
978 for (i = 0; i < lck->lls_nr; ++i) {
979 struct lov_lock_sub *lls;
980 struct lovsub_lock *lsl;
981 struct cl_lock *sublock;
984 lls = &lck->lls_sub[i];
989 sublock = lsl->lss_cl.cls_lock;
990 rc = lov_sublock_lock(env, lck, lls, closure, NULL);
992 if (lck->lls_sub[i].sub_flags & LSF_HELD)
993 lov_sublock_release(env, lck, i, 1, 0);
994 if (sublock->cll_state < CLS_FREEING) {
995 struct lov_lock_link *link;
997 link = lov_lock_link_find(env, lck, lsl);
998 LASSERT(link != NULL);
999 lov_lock_unlink(env, link, lsl);
1000 LASSERT(lck->lls_sub[i].sub_lock == NULL);
1002 lov_sublock_unlock(env, lsl, closure, NULL);
1003 } else if (rc == CLO_REPEAT) {
1004 --i; /* repeat with this lock */
1006 CL_LOCK_DEBUG(D_ERROR, env, sublock,
1007 "Cannot get sub-lock for delete: %i\n",
1011 cl_lock_closure_fini(closure);
1015 static int lov_lock_print(const struct lu_env *env, void *cookie,
1016 lu_printer_t p, const struct cl_lock_slice *slice)
1018 struct lov_lock *lck = cl2lov_lock(slice);
1021 (*p)(env, cookie, "%d\n", lck->lls_nr);
1022 for (i = 0; i < lck->lls_nr; ++i) {
1023 struct lov_lock_sub *sub;
1025 sub = &lck->lls_sub[i];
1026 (*p)(env, cookie, " %d %x: ", i, sub->sub_flags);
1027 if (sub->sub_lock != NULL)
1028 cl_lock_print(env, cookie, p,
1029 sub->sub_lock->lss_cl.cls_lock);
1031 (*p)(env, cookie, "---\n");
1036 static const struct cl_lock_operations lov_lock_ops = {
1037 .clo_fini = lov_lock_fini,
1038 .clo_enqueue = lov_lock_enqueue,
1039 .clo_wait = lov_lock_wait,
1040 .clo_use = lov_lock_use,
1041 .clo_unuse = lov_lock_unuse,
1042 .clo_fits_into = lov_lock_fits_into,
1043 .clo_delete = lov_lock_delete,
1044 .clo_print = lov_lock_print
1047 int lov_lock_init_raid0(const struct lu_env *env, struct cl_object *obj,
1048 struct cl_lock *lock, const struct cl_io *io)
1050 struct lov_lock *lck;
1054 OBD_SLAB_ALLOC_PTR_GFP(lck, lov_lock_kmem, CFS_ALLOC_IO);
1056 cl_lock_slice_add(lock, &lck->lls_cl, obj, &lov_lock_ops);
1057 result = lov_lock_sub_init(env, lck, io);
1063 static struct cl_lock_closure *lov_closure_get(const struct lu_env *env,
1064 struct cl_lock *parent)
1066 struct cl_lock_closure *closure;
1068 closure = &lov_env_info(env)->lti_closure;
1069 LASSERT(list_empty(&closure->clc_list));
1070 cl_lock_closure_init(env, closure, parent, 1);