4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
27 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2012, 2014, Intel Corporation.
34 * This file is part of Lustre, http://www.lustre.org/
35 * Lustre is a trademark of Sun Microsystems, Inc.
37 * osc cache management.
39 * Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
42 #define DEBUG_SUBSYSTEM S_OSC
44 #include "osc_cl_internal.h"
45 #include "osc_internal.h"
47 static int extent_debug; /* set it to be true for more debug */
49 static void osc_update_pending(struct osc_object *obj, int cmd, int delta);
50 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
51 enum osc_extent_state state);
52 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
53 struct osc_async_page *oap, int sent, int rc);
54 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
56 static int osc_refresh_count(const struct lu_env *env,
57 struct osc_async_page *oap, int cmd);
58 static int osc_io_unplug_async(const struct lu_env *env,
59 struct client_obd *cli, struct osc_object *osc);
60 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
61 unsigned int lost_grant);
63 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
64 const char *func, int line);
65 #define osc_extent_tree_dump(lvl, obj) \
66 osc_extent_tree_dump0(lvl, obj, __func__, __LINE__)
72 /* ------------------ osc extent ------------------ */
73 static inline char *ext_flags(struct osc_extent *ext, char *flags)
76 *buf++ = ext->oe_rw ? 'r' : 'w';
89 if (ext->oe_trunc_pending)
91 if (ext->oe_fsync_wait)
97 static inline char list_empty_marker(struct list_head *list)
99 return list_empty(list) ? '-' : '+';
102 #define EXTSTR "[%lu -> %lu/%lu]"
103 #define EXTPARA(ext) (ext)->oe_start, (ext)->oe_end, (ext)->oe_max_end
104 static const char *oes_strings[] = {
105 "inv", "active", "cache", "locking", "lockdone", "rpc", "trunc", NULL };
107 #define OSC_EXTENT_DUMP(lvl, extent, fmt, ...) do { \
108 struct osc_extent *__ext = (extent); \
112 "extent %p@{" EXTSTR ", " \
113 "[%d|%d|%c|%s|%s|%p], [%d|%d|%c|%c|%p|%u|%p]} " fmt, \
114 /* ----- extent part 0 ----- */ \
115 __ext, EXTPARA(__ext), \
116 /* ----- part 1 ----- */ \
117 atomic_read(&__ext->oe_refc), \
118 atomic_read(&__ext->oe_users), \
119 list_empty_marker(&__ext->oe_link), \
120 oes_strings[__ext->oe_state], ext_flags(__ext, __buf), \
122 /* ----- part 2 ----- */ \
123 __ext->oe_grants, __ext->oe_nr_pages, \
124 list_empty_marker(&__ext->oe_pages), \
125 waitqueue_active(&__ext->oe_waitq) ? '+' : '-', \
126 __ext->oe_dlmlock, __ext->oe_mppr, __ext->oe_owner, \
127 /* ----- part 4 ----- */ \
129 if (lvl == D_ERROR && __ext->oe_dlmlock != NULL) \
130 LDLM_ERROR(__ext->oe_dlmlock, "extent: %p\n", __ext); \
132 LDLM_DEBUG(__ext->oe_dlmlock, "extent: %p\n", __ext); \
136 #define EASSERTF(expr, ext, fmt, args...) do { \
138 OSC_EXTENT_DUMP(D_ERROR, (ext), fmt, ##args); \
139 osc_extent_tree_dump(D_ERROR, (ext)->oe_obj); \
145 #define EASSERT(expr, ext) EASSERTF(expr, ext, "\n")
147 static inline struct osc_extent *rb_extent(struct rb_node *n)
152 return container_of(n, struct osc_extent, oe_node);
155 static inline struct osc_extent *next_extent(struct osc_extent *ext)
160 LASSERT(ext->oe_intree);
161 return rb_extent(rb_next(&ext->oe_node));
164 static inline struct osc_extent *prev_extent(struct osc_extent *ext)
169 LASSERT(ext->oe_intree);
170 return rb_extent(rb_prev(&ext->oe_node));
173 static inline struct osc_extent *first_extent(struct osc_object *obj)
175 return rb_extent(rb_first(&obj->oo_root));
178 /* object must be locked by caller. */
179 static int osc_extent_sanity_check0(struct osc_extent *ext,
180 const char *func, const int line)
182 struct osc_object *obj = ext->oe_obj;
183 struct osc_async_page *oap;
187 if (!osc_object_is_locked(obj))
190 if (ext->oe_state >= OES_STATE_MAX)
193 if (atomic_read(&ext->oe_refc) <= 0)
196 if (atomic_read(&ext->oe_refc) < atomic_read(&ext->oe_users))
199 switch (ext->oe_state) {
201 if (ext->oe_nr_pages > 0 || !list_empty(&ext->oe_pages))
206 if (atomic_read(&ext->oe_users) == 0)
210 if (ext->oe_fsync_wait && !ext->oe_urgent)
214 if (ext->oe_grants == 0)
216 if (ext->oe_fsync_wait && !ext->oe_urgent && !ext->oe_hp)
219 if (atomic_read(&ext->oe_users) > 0)
223 if (ext->oe_max_end < ext->oe_end || ext->oe_end < ext->oe_start)
226 if (ext->oe_sync && ext->oe_grants > 0)
229 if (ext->oe_dlmlock != NULL) {
230 struct ldlm_extent *extent;
232 extent = &ext->oe_dlmlock->l_policy_data.l_extent;
233 if (!(extent->start <= cl_offset(osc2cl(obj), ext->oe_start) &&
234 extent->end >= cl_offset(osc2cl(obj), ext->oe_max_end)))
237 if (!(ext->oe_dlmlock->l_granted_mode & (LCK_PW | LCK_GROUP)))
241 if (ext->oe_nr_pages > ext->oe_mppr)
244 /* Do not verify page list if extent is in RPC. This is because an
245 * in-RPC extent is supposed to be exclusively accessible w/o lock. */
246 if (ext->oe_state > OES_CACHE)
253 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
254 pgoff_t index = osc_index(oap2osc(oap));
256 if (index > ext->oe_end || index < ext->oe_start)
259 if (page_count != ext->oe_nr_pages)
264 OSC_EXTENT_DUMP(D_ERROR, ext,
265 "%s:%d sanity check %p failed with rc = %d\n",
266 func, line, ext, rc);
270 #define sanity_check_nolock(ext) \
271 osc_extent_sanity_check0(ext, __func__, __LINE__)
273 #define sanity_check(ext) ({ \
275 osc_object_lock((ext)->oe_obj); \
276 __res = sanity_check_nolock(ext); \
277 osc_object_unlock((ext)->oe_obj); \
283 * sanity check - to make sure there is no overlapped extent in the tree.
285 static int osc_extent_is_overlapped(struct osc_object *obj,
286 struct osc_extent *ext)
288 struct osc_extent *tmp;
290 LASSERT(osc_object_is_locked(obj));
295 for (tmp = first_extent(obj); tmp != NULL; tmp = next_extent(tmp)) {
298 if (tmp->oe_end >= ext->oe_start &&
299 tmp->oe_start <= ext->oe_end)
305 static void osc_extent_state_set(struct osc_extent *ext, int state)
307 LASSERT(osc_object_is_locked(ext->oe_obj));
308 LASSERT(state >= OES_INV && state < OES_STATE_MAX);
310 /* Never try to sanity check a state changing extent :-) */
311 /* LASSERT(sanity_check_nolock(ext) == 0); */
313 /* TODO: validate the state machine */
314 ext->oe_state = state;
315 wake_up_all(&ext->oe_waitq);
318 static struct osc_extent *osc_extent_alloc(struct osc_object *obj)
320 struct osc_extent *ext;
322 OBD_SLAB_ALLOC_PTR_GFP(ext, osc_extent_kmem, GFP_IOFS);
326 RB_CLEAR_NODE(&ext->oe_node);
328 atomic_set(&ext->oe_refc, 1);
329 atomic_set(&ext->oe_users, 0);
330 INIT_LIST_HEAD(&ext->oe_link);
331 ext->oe_state = OES_INV;
332 INIT_LIST_HEAD(&ext->oe_pages);
333 init_waitqueue_head(&ext->oe_waitq);
334 ext->oe_dlmlock = NULL;
339 static void osc_extent_free(struct osc_extent *ext)
341 OBD_SLAB_FREE_PTR(ext, osc_extent_kmem);
344 static struct osc_extent *osc_extent_get(struct osc_extent *ext)
346 LASSERT(atomic_read(&ext->oe_refc) >= 0);
347 atomic_inc(&ext->oe_refc);
351 static void osc_extent_put(const struct lu_env *env, struct osc_extent *ext)
353 LASSERT(atomic_read(&ext->oe_refc) > 0);
354 if (atomic_dec_and_test(&ext->oe_refc)) {
355 LASSERT(list_empty(&ext->oe_link));
356 LASSERT(atomic_read(&ext->oe_users) == 0);
357 LASSERT(ext->oe_state == OES_INV);
358 LASSERT(!ext->oe_intree);
360 if (ext->oe_dlmlock != NULL) {
361 lu_ref_add(&ext->oe_dlmlock->l_reference,
363 LDLM_LOCK_PUT(ext->oe_dlmlock);
364 ext->oe_dlmlock = NULL;
366 osc_extent_free(ext);
371 * osc_extent_put_trust() is a special version of osc_extent_put() when
372 * it's known that the caller is not the last user. This is to address the
373 * problem of lacking of lu_env ;-).
375 static void osc_extent_put_trust(struct osc_extent *ext)
377 LASSERT(atomic_read(&ext->oe_refc) > 1);
378 LASSERT(osc_object_is_locked(ext->oe_obj));
379 atomic_dec(&ext->oe_refc);
383 * Return the extent which includes pgoff @index, or return the greatest
384 * previous extent in the tree.
386 static struct osc_extent *osc_extent_search(struct osc_object *obj,
389 struct rb_node *n = obj->oo_root.rb_node;
390 struct osc_extent *tmp, *p = NULL;
392 LASSERT(osc_object_is_locked(obj));
395 if (index < tmp->oe_start) {
397 } else if (index > tmp->oe_end) {
408 * Return the extent covering @index, otherwise return NULL.
409 * caller must have held object lock.
411 static struct osc_extent *osc_extent_lookup(struct osc_object *obj,
414 struct osc_extent *ext;
416 ext = osc_extent_search(obj, index);
417 if (ext != NULL && ext->oe_start <= index && index <= ext->oe_end)
418 return osc_extent_get(ext);
422 /* caller must have held object lock. */
423 static void osc_extent_insert(struct osc_object *obj, struct osc_extent *ext)
425 struct rb_node **n = &obj->oo_root.rb_node;
426 struct rb_node *parent = NULL;
427 struct osc_extent *tmp;
429 LASSERT(ext->oe_intree == 0);
430 LASSERT(ext->oe_obj == obj);
431 LASSERT(osc_object_is_locked(obj));
436 if (ext->oe_end < tmp->oe_start)
438 else if (ext->oe_start > tmp->oe_end)
441 EASSERTF(0, tmp, EXTSTR"\n", EXTPARA(ext));
443 rb_link_node(&ext->oe_node, parent, n);
444 rb_insert_color(&ext->oe_node, &obj->oo_root);
449 /* caller must have held object lock. */
450 static void osc_extent_erase(struct osc_extent *ext)
452 struct osc_object *obj = ext->oe_obj;
453 LASSERT(osc_object_is_locked(obj));
454 if (ext->oe_intree) {
455 rb_erase(&ext->oe_node, &obj->oo_root);
457 /* rbtree held a refcount */
458 osc_extent_put_trust(ext);
462 static struct osc_extent *osc_extent_hold(struct osc_extent *ext)
464 struct osc_object *obj = ext->oe_obj;
466 LASSERT(osc_object_is_locked(obj));
467 LASSERT(ext->oe_state == OES_ACTIVE || ext->oe_state == OES_CACHE);
468 if (ext->oe_state == OES_CACHE) {
469 osc_extent_state_set(ext, OES_ACTIVE);
470 osc_update_pending(obj, OBD_BRW_WRITE, -ext->oe_nr_pages);
472 atomic_inc(&ext->oe_users);
473 list_del_init(&ext->oe_link);
474 return osc_extent_get(ext);
477 static void __osc_extent_remove(struct osc_extent *ext)
479 LASSERT(osc_object_is_locked(ext->oe_obj));
480 LASSERT(list_empty(&ext->oe_pages));
481 osc_extent_erase(ext);
482 list_del_init(&ext->oe_link);
483 osc_extent_state_set(ext, OES_INV);
484 OSC_EXTENT_DUMP(D_CACHE, ext, "destroyed.\n");
487 static void osc_extent_remove(struct osc_extent *ext)
489 struct osc_object *obj = ext->oe_obj;
491 osc_object_lock(obj);
492 __osc_extent_remove(ext);
493 osc_object_unlock(obj);
497 * This function is used to merge extents to get better performance. It checks
498 * if @cur and @victim are contiguous at chunk level.
500 static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
501 struct osc_extent *victim)
503 struct osc_object *obj = cur->oe_obj;
508 LASSERT(cur->oe_state == OES_CACHE);
509 LASSERT(osc_object_is_locked(obj));
513 if (victim->oe_state != OES_CACHE || victim->oe_fsync_wait)
516 if (cur->oe_max_end != victim->oe_max_end)
519 LASSERT(cur->oe_dlmlock == victim->oe_dlmlock);
520 ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_CACHE_SHIFT;
521 chunk_start = cur->oe_start >> ppc_bits;
522 chunk_end = cur->oe_end >> ppc_bits;
523 if (chunk_start != (victim->oe_end >> ppc_bits) + 1 &&
524 chunk_end + 1 != victim->oe_start >> ppc_bits)
527 OSC_EXTENT_DUMP(D_CACHE, victim, "will be merged by %p.\n", cur);
529 cur->oe_start = min(cur->oe_start, victim->oe_start);
530 cur->oe_end = max(cur->oe_end, victim->oe_end);
531 cur->oe_grants += victim->oe_grants;
532 cur->oe_nr_pages += victim->oe_nr_pages;
533 /* only the following bits are needed to merge */
534 cur->oe_urgent |= victim->oe_urgent;
535 cur->oe_memalloc |= victim->oe_memalloc;
536 list_splice_init(&victim->oe_pages, &cur->oe_pages);
537 list_del_init(&victim->oe_link);
538 victim->oe_nr_pages = 0;
540 osc_extent_get(victim);
541 __osc_extent_remove(victim);
542 osc_extent_put(env, victim);
544 OSC_EXTENT_DUMP(D_CACHE, cur, "after merging %p.\n", victim);
549 * Drop user count of osc_extent, and unplug IO asynchronously.
551 int osc_extent_release(const struct lu_env *env, struct osc_extent *ext)
553 struct osc_object *obj = ext->oe_obj;
557 LASSERT(atomic_read(&ext->oe_users) > 0);
558 LASSERT(sanity_check(ext) == 0);
559 LASSERT(ext->oe_grants > 0);
561 if (atomic_dec_and_lock(&ext->oe_users, &obj->oo_lock)) {
562 LASSERT(ext->oe_state == OES_ACTIVE);
563 if (ext->oe_trunc_pending) {
564 /* a truncate process is waiting for this extent.
565 * This may happen due to a race, check
566 * osc_cache_truncate_start(). */
567 osc_extent_state_set(ext, OES_TRUNC);
568 ext->oe_trunc_pending = 0;
570 osc_extent_state_set(ext, OES_CACHE);
571 osc_update_pending(obj, OBD_BRW_WRITE,
574 /* try to merge the previous and next extent. */
575 osc_extent_merge(env, ext, prev_extent(ext));
576 osc_extent_merge(env, ext, next_extent(ext));
579 list_move_tail(&ext->oe_link,
580 &obj->oo_urgent_exts);
582 osc_object_unlock(obj);
584 osc_io_unplug_async(env, osc_cli(obj), obj);
586 osc_extent_put(env, ext);
590 static inline int overlapped(struct osc_extent *ex1, struct osc_extent *ex2)
592 return !(ex1->oe_end < ex2->oe_start || ex2->oe_end < ex1->oe_start);
596 * Find or create an extent which includes @index, core function to manage
599 static struct osc_extent *osc_extent_find(const struct lu_env *env,
600 struct osc_object *obj, pgoff_t index,
601 unsigned int *grants)
603 struct client_obd *cli = osc_cli(obj);
604 struct osc_lock *olck;
605 struct cl_lock_descr *descr;
606 struct osc_extent *cur;
607 struct osc_extent *ext;
608 struct osc_extent *conflict = NULL;
609 struct osc_extent *found = NULL;
612 unsigned int max_pages; /* max_pages_per_rpc */
613 unsigned int chunksize;
614 int ppc_bits; /* pages per chunk bits */
619 cur = osc_extent_alloc(obj);
621 RETURN(ERR_PTR(-ENOMEM));
623 olck = osc_env_io(env)->oi_write_osclock;
624 LASSERTF(olck != NULL, "page %lu is not covered by lock\n", index);
625 LASSERT(olck->ols_state == OLS_GRANTED);
627 descr = &olck->ols_cl.cls_lock->cll_descr;
628 LASSERT(descr->cld_mode >= CLM_WRITE);
630 LASSERT(cli->cl_chunkbits >= PAGE_CACHE_SHIFT);
631 ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
632 chunk_mask = ~((1 << ppc_bits) - 1);
633 chunksize = 1 << cli->cl_chunkbits;
634 chunk = index >> ppc_bits;
636 /* align end to rpc edge, rpc size may not be a power 2 integer. */
637 max_pages = cli->cl_max_pages_per_rpc;
638 LASSERT((max_pages & ~chunk_mask) == 0);
639 max_end = index - (index % max_pages) + max_pages - 1;
640 max_end = min_t(pgoff_t, max_end, descr->cld_end);
642 /* initialize new extent by parameters so far */
643 cur->oe_max_end = max_end;
644 cur->oe_start = index & chunk_mask;
645 cur->oe_end = ((index + ~chunk_mask + 1) & chunk_mask) - 1;
646 if (cur->oe_start < descr->cld_start)
647 cur->oe_start = descr->cld_start;
648 if (cur->oe_end > max_end)
649 cur->oe_end = max_end;
651 cur->oe_mppr = max_pages;
652 if (olck->ols_dlmlock != NULL) {
653 LASSERT(olck->ols_hold);
654 cur->oe_dlmlock = LDLM_LOCK_GET(olck->ols_dlmlock);
655 lu_ref_add(&olck->ols_dlmlock->l_reference, "osc_extent", cur);
658 /* grants has been allocated by caller */
659 LASSERTF(*grants >= chunksize + cli->cl_extent_tax,
660 "%u/%u/%u.\n", *grants, chunksize, cli->cl_extent_tax);
661 LASSERTF((max_end - cur->oe_start) < max_pages, EXTSTR"\n",
665 osc_object_lock(obj);
666 ext = osc_extent_search(obj, cur->oe_start);
668 ext = first_extent(obj);
669 while (ext != NULL) {
670 pgoff_t ext_chk_start = ext->oe_start >> ppc_bits;
671 pgoff_t ext_chk_end = ext->oe_end >> ppc_bits;
673 LASSERT(sanity_check_nolock(ext) == 0);
674 if (chunk > ext_chk_end + 1)
677 /* if covering by different locks, no chance to match */
678 if (olck->ols_dlmlock != ext->oe_dlmlock) {
679 EASSERTF(!overlapped(ext, cur), ext,
680 EXTSTR"\n", EXTPARA(cur));
682 ext = next_extent(ext);
686 /* discontiguous chunks? */
687 if (chunk + 1 < ext_chk_start) {
688 ext = next_extent(ext);
692 /* ok, from now on, ext and cur have these attrs:
693 * 1. covered by the same lock
694 * 2. contiguous at chunk level or overlapping. */
696 if (overlapped(ext, cur)) {
697 /* cur is the minimum unit, so overlapping means
699 EASSERTF((ext->oe_start <= cur->oe_start &&
700 ext->oe_end >= cur->oe_end),
701 ext, EXTSTR"\n", EXTPARA(cur));
703 if (ext->oe_state > OES_CACHE || ext->oe_fsync_wait) {
704 /* for simplicity, we wait for this extent to
705 * finish before going forward. */
706 conflict = osc_extent_get(ext);
710 found = osc_extent_hold(ext);
714 /* non-overlapped extent */
715 if (ext->oe_state != OES_CACHE || ext->oe_fsync_wait) {
716 /* we can't do anything for a non OES_CACHE extent, or
717 * if there is someone waiting for this extent to be
718 * flushed, try next one. */
719 ext = next_extent(ext);
723 /* check if they belong to the same rpc slot before trying to
724 * merge. the extents are not overlapped and contiguous at
725 * chunk level to get here. */
726 if (ext->oe_max_end != max_end) {
727 /* if they don't belong to the same RPC slot or
728 * max_pages_per_rpc has ever changed, do not merge. */
729 ext = next_extent(ext);
733 /* it's required that an extent must be contiguous at chunk
734 * level so that we know the whole extent is covered by grant
735 * (the pages in the extent are NOT required to be contiguous).
736 * Otherwise, it will be too much difficult to know which
737 * chunks have grants allocated. */
739 /* try to do front merge - extend ext's start */
740 if (chunk + 1 == ext_chk_start) {
741 /* ext must be chunk size aligned */
742 EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
744 /* pull ext's start back to cover cur */
745 ext->oe_start = cur->oe_start;
746 ext->oe_grants += chunksize;
747 *grants -= chunksize;
749 found = osc_extent_hold(ext);
750 } else if (chunk == ext_chk_end + 1) {
752 ext->oe_end = cur->oe_end;
753 ext->oe_grants += chunksize;
754 *grants -= chunksize;
756 /* try to merge with the next one because we just fill
758 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
759 /* we can save extent tax from next extent */
760 *grants += cli->cl_extent_tax;
762 found = osc_extent_hold(ext);
767 ext = next_extent(ext);
770 osc_extent_tree_dump(D_CACHE, obj);
772 LASSERT(conflict == NULL);
773 if (!IS_ERR(found)) {
774 LASSERT(found->oe_dlmlock == cur->oe_dlmlock);
775 OSC_EXTENT_DUMP(D_CACHE, found,
776 "found caching ext for %lu.\n", index);
778 } else if (conflict == NULL) {
779 /* create a new extent */
780 EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
781 cur->oe_grants = chunksize + cli->cl_extent_tax;
782 *grants -= cur->oe_grants;
783 LASSERT(*grants >= 0);
785 cur->oe_state = OES_CACHE;
786 found = osc_extent_hold(cur);
787 osc_extent_insert(obj, cur);
788 OSC_EXTENT_DUMP(D_CACHE, cur, "add into tree %lu/%lu.\n",
789 index, descr->cld_end);
791 osc_object_unlock(obj);
793 if (conflict != NULL) {
794 LASSERT(found == NULL);
796 /* waiting for IO to finish. Please notice that it's impossible
797 * to be an OES_TRUNC extent. */
798 rc = osc_extent_wait(env, conflict, OES_INV);
799 osc_extent_put(env, conflict);
802 GOTO(out, found = ERR_PTR(rc));
809 osc_extent_put(env, cur);
810 LASSERT(*grants >= 0);
815 * Called when IO is finished to an extent.
817 int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
820 struct client_obd *cli = osc_cli(ext->oe_obj);
821 struct osc_async_page *oap;
822 struct osc_async_page *tmp;
823 int nr_pages = ext->oe_nr_pages;
825 int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
830 OSC_EXTENT_DUMP(D_CACHE, ext, "extent finished.\n");
832 ext->oe_rc = rc ?: ext->oe_nr_pages;
833 EASSERT(ergo(rc == 0, ext->oe_state == OES_RPC), ext);
835 osc_lru_add_batch(cli, &ext->oe_pages);
836 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
838 list_del_init(&oap->oap_rpc_item);
839 list_del_init(&oap->oap_pending_item);
840 if (last_off <= oap->oap_obj_off) {
841 last_off = oap->oap_obj_off;
842 last_count = oap->oap_count;
846 osc_ap_completion(env, cli, oap, sent, rc);
848 EASSERT(ext->oe_nr_pages == 0, ext);
851 lost_grant = ext->oe_grants;
852 } else if (blocksize < PAGE_CACHE_SIZE &&
853 last_count != PAGE_CACHE_SIZE) {
854 /* For short writes we shouldn't count parts of pages that
855 * span a whole chunk on the OST side, or our accounting goes
856 * wrong. Should match the code in filter_grant_check. */
857 int offset = last_off & ~PAGE_MASK;
858 int count = last_count + (offset & (blocksize - 1));
859 int end = (offset + last_count) & (blocksize - 1);
861 count += blocksize - end;
863 lost_grant = PAGE_CACHE_SIZE - count;
865 if (ext->oe_grants > 0)
866 osc_free_grant(cli, nr_pages, lost_grant);
868 osc_extent_remove(ext);
869 /* put the refcount for RPC */
870 osc_extent_put(env, ext);
874 static int extent_wait_cb(struct osc_extent *ext, enum osc_extent_state state)
878 osc_object_lock(ext->oe_obj);
879 ret = ext->oe_state == state;
880 osc_object_unlock(ext->oe_obj);
886 * Wait for the extent's state to become @state.
888 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
889 enum osc_extent_state state)
891 struct osc_object *obj = ext->oe_obj;
892 struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(600), NULL,
893 LWI_ON_SIGNAL_NOOP, NULL);
897 osc_object_lock(obj);
898 LASSERT(sanity_check_nolock(ext) == 0);
899 /* `Kick' this extent only if the caller is waiting for it to be
901 if (state == OES_INV && !ext->oe_urgent && !ext->oe_hp) {
902 if (ext->oe_state == OES_ACTIVE) {
904 } else if (ext->oe_state == OES_CACHE) {
906 osc_extent_hold(ext);
910 osc_object_unlock(obj);
912 osc_extent_release(env, ext);
914 /* wait for the extent until its state becomes @state */
915 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state), &lwi);
916 if (rc == -ETIMEDOUT) {
917 OSC_EXTENT_DUMP(D_ERROR, ext,
918 "%s: wait ext to %u timedout, recovery in progress?\n",
919 osc_export(obj)->exp_obd->obd_name, state);
921 lwi = LWI_INTR(NULL, NULL);
922 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state),
925 if (rc == 0 && ext->oe_rc < 0)
931 * Discard pages with index greater than @size. If @ext is overlapped with
932 * @size, then partial truncate happens.
934 static int osc_extent_truncate(struct osc_extent *ext, pgoff_t trunc_index,
937 struct cl_env_nest nest;
940 struct osc_object *obj = ext->oe_obj;
941 struct client_obd *cli = osc_cli(obj);
942 struct osc_async_page *oap;
943 struct osc_async_page *tmp;
944 int pages_in_chunk = 0;
945 int ppc_bits = cli->cl_chunkbits -
947 __u64 trunc_chunk = trunc_index >> ppc_bits;
953 LASSERT(sanity_check(ext) == 0);
954 LASSERT(ext->oe_state == OES_TRUNC);
955 LASSERT(!ext->oe_urgent);
957 /* Request new lu_env.
958 * We can't use that env from osc_cache_truncate_start() because
959 * it's from lov_io_sub and not fully initialized. */
960 env = cl_env_nested_get(&nest);
961 io = &osc_env_info(env)->oti_io;
962 io->ci_obj = cl_object_top(osc2cl(obj));
963 rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
967 /* discard all pages with index greater than trunc_index */
968 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
970 pgoff_t index = osc_index(oap2osc(oap));
971 struct cl_page *page = oap2cl_page(oap);
973 LASSERT(list_empty(&oap->oap_rpc_item));
975 /* only discard the pages with their index greater than
976 * trunc_index, and ... */
977 if (index < trunc_index ||
978 (index == trunc_index && partial)) {
979 /* accounting how many pages remaining in the chunk
980 * so that we can calculate grants correctly. */
981 if (index >> ppc_bits == trunc_chunk)
986 list_del_init(&oap->oap_pending_item);
989 lu_ref_add(&page->cp_reference, "truncate", current);
991 if (cl_page_own(env, io, page) == 0) {
992 cl_page_discard(env, io, page);
993 cl_page_disown(env, io, page);
995 LASSERT(page->cp_state == CPS_FREEING);
999 lu_ref_del(&page->cp_reference, "truncate", current);
1000 cl_page_put(env, page);
1005 EASSERTF(ergo(ext->oe_start >= trunc_index + !!partial,
1006 ext->oe_nr_pages == 0),
1007 ext, "trunc_index %lu, partial %d\n", trunc_index, partial);
1009 osc_object_lock(obj);
1010 if (ext->oe_nr_pages == 0) {
1011 LASSERT(pages_in_chunk == 0);
1012 grants = ext->oe_grants;
1014 } else { /* calculate how many grants we can free */
1015 int chunks = (ext->oe_end >> ppc_bits) - trunc_chunk;
1019 /* if there is no pages in this chunk, we can also free grants
1020 * for the last chunk */
1021 if (pages_in_chunk == 0) {
1022 /* if this is the 1st chunk and no pages in this chunk,
1023 * ext->oe_nr_pages must be zero, so we should be in
1024 * the other if-clause. */
1025 LASSERT(trunc_chunk > 0);
1030 /* this is what we can free from this extent */
1031 grants = chunks << cli->cl_chunkbits;
1032 ext->oe_grants -= grants;
1033 last_index = ((trunc_chunk + 1) << ppc_bits) - 1;
1034 ext->oe_end = min(last_index, ext->oe_max_end);
1035 LASSERT(ext->oe_end >= ext->oe_start);
1036 LASSERT(ext->oe_grants > 0);
1038 osc_object_unlock(obj);
1040 if (grants > 0 || nr_pages > 0)
1041 osc_free_grant(cli, nr_pages, grants);
1044 cl_io_fini(env, io);
1045 cl_env_nested_put(&nest, env);
1050 * This function is used to make the extent prepared for transfer.
1051 * A race with flusing page - ll_writepage() has to be handled cautiously.
1053 static int osc_extent_make_ready(const struct lu_env *env,
1054 struct osc_extent *ext)
1056 struct osc_async_page *oap;
1057 struct osc_async_page *last = NULL;
1058 struct osc_object *obj = ext->oe_obj;
1059 unsigned int page_count = 0;
1063 /* we're going to grab page lock, so object lock must not be taken. */
1064 LASSERT(sanity_check(ext) == 0);
1065 /* in locking state, any process should not touch this extent. */
1066 EASSERT(ext->oe_state == OES_LOCKING, ext);
1067 EASSERT(ext->oe_owner != NULL, ext);
1069 OSC_EXTENT_DUMP(D_CACHE, ext, "make ready\n");
1071 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1073 if (last == NULL || last->oap_obj_off < oap->oap_obj_off)
1076 /* checking ASYNC_READY is race safe */
1077 if ((oap->oap_async_flags & ASYNC_READY) != 0)
1080 rc = osc_make_ready(env, oap, OBD_BRW_WRITE);
1083 spin_lock(&oap->oap_lock);
1084 oap->oap_async_flags |= ASYNC_READY;
1085 spin_unlock(&oap->oap_lock);
1088 LASSERT((oap->oap_async_flags & ASYNC_READY) != 0);
1091 LASSERTF(0, "unknown return code: %d\n", rc);
1095 LASSERT(page_count == ext->oe_nr_pages);
1096 LASSERT(last != NULL);
1097 /* the last page is the only one we need to refresh its count by
1098 * the size of file. */
1099 if (!(last->oap_async_flags & ASYNC_COUNT_STABLE)) {
1100 int last_oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE);
1101 LASSERT(last_oap_count > 0);
1102 LASSERT(last->oap_page_off + last_oap_count <= PAGE_CACHE_SIZE);
1103 last->oap_count = last_oap_count;
1104 spin_lock(&last->oap_lock);
1105 last->oap_async_flags |= ASYNC_COUNT_STABLE;
1106 spin_unlock(&last->oap_lock);
1109 /* for the rest of pages, we don't need to call osf_refresh_count()
1110 * because it's known they are not the last page */
1111 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1112 if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
1113 oap->oap_count = PAGE_CACHE_SIZE - oap->oap_page_off;
1114 spin_lock(&oap->oap_lock);
1115 oap->oap_async_flags |= ASYNC_COUNT_STABLE;
1116 spin_unlock(&oap->oap_lock);
1120 osc_object_lock(obj);
1121 osc_extent_state_set(ext, OES_RPC);
1122 osc_object_unlock(obj);
1123 /* get a refcount for RPC. */
1124 osc_extent_get(ext);
1130 * Quick and simple version of osc_extent_find(). This function is frequently
1131 * called to expand the extent for the same IO. To expand the extent, the
1132 * page index must be in the same or next chunk of ext->oe_end.
1134 static int osc_extent_expand(struct osc_extent *ext, pgoff_t index,
1135 unsigned int *grants)
1137 struct osc_object *obj = ext->oe_obj;
1138 struct client_obd *cli = osc_cli(obj);
1139 struct osc_extent *next;
1140 int ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
1141 pgoff_t chunk = index >> ppc_bits;
1144 unsigned int chunksize = 1 << cli->cl_chunkbits;
1148 LASSERT(ext->oe_max_end >= index && ext->oe_start <= index);
1149 osc_object_lock(obj);
1150 LASSERT(sanity_check_nolock(ext) == 0);
1151 end_chunk = ext->oe_end >> ppc_bits;
1152 if (chunk > end_chunk + 1)
1153 GOTO(out, rc = -ERANGE);
1155 if (end_chunk >= chunk)
1158 LASSERT(end_chunk + 1 == chunk);
1159 /* try to expand this extent to cover @index */
1160 end_index = min(ext->oe_max_end, ((chunk + 1) << ppc_bits) - 1);
1162 next = next_extent(ext);
1163 if (next != NULL && next->oe_start <= end_index)
1164 /* complex mode - overlapped with the next extent,
1165 * this case will be handled by osc_extent_find() */
1166 GOTO(out, rc = -EAGAIN);
1168 ext->oe_end = end_index;
1169 ext->oe_grants += chunksize;
1170 *grants -= chunksize;
1171 LASSERT(*grants >= 0);
1172 EASSERTF(osc_extent_is_overlapped(obj, ext) == 0, ext,
1173 "overlapped after expanding for %lu.\n", index);
1177 osc_object_unlock(obj);
1181 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
1182 const char *func, int line)
1184 struct osc_extent *ext;
1187 CDEBUG(level, "Dump object %p extents at %s:%d, mppr: %u.\n",
1188 obj, func, line, osc_cli(obj)->cl_max_pages_per_rpc);
1190 /* osc_object_lock(obj); */
1192 for (ext = first_extent(obj); ext != NULL; ext = next_extent(ext))
1193 OSC_EXTENT_DUMP(level, ext, "in tree %d.\n", cnt++);
1196 list_for_each_entry(ext, &obj->oo_hp_exts, oe_link)
1197 OSC_EXTENT_DUMP(level, ext, "hp %d.\n", cnt++);
1200 list_for_each_entry(ext, &obj->oo_urgent_exts, oe_link)
1201 OSC_EXTENT_DUMP(level, ext, "urgent %d.\n", cnt++);
1204 list_for_each_entry(ext, &obj->oo_reading_exts, oe_link)
1205 OSC_EXTENT_DUMP(level, ext, "reading %d.\n", cnt++);
1206 /* osc_object_unlock(obj); */
1209 /* ------------------ osc extent end ------------------ */
1211 static inline int osc_is_ready(struct osc_object *osc)
1213 return !list_empty(&osc->oo_ready_item) ||
1214 !list_empty(&osc->oo_hp_ready_item);
1217 #define OSC_IO_DEBUG(OSC, STR, args...) \
1218 CDEBUG(D_CACHE, "obj %p ready %d|%c|%c wr %d|%c|%c rd %d|%c " STR, \
1219 (OSC), osc_is_ready(OSC), \
1220 list_empty_marker(&(OSC)->oo_hp_ready_item), \
1221 list_empty_marker(&(OSC)->oo_ready_item), \
1222 atomic_read(&(OSC)->oo_nr_writes), \
1223 list_empty_marker(&(OSC)->oo_hp_exts), \
1224 list_empty_marker(&(OSC)->oo_urgent_exts), \
1225 atomic_read(&(OSC)->oo_nr_reads), \
1226 list_empty_marker(&(OSC)->oo_reading_exts), \
1229 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
1232 struct osc_page *opg = oap2osc_page(oap);
1233 struct cl_page *page = oap2cl_page(oap);
1236 LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
1239 result = cl_page_make_ready(env, page, CRT_WRITE);
1241 opg->ops_submit_time = cfs_time_current();
1245 static int osc_refresh_count(const struct lu_env *env,
1246 struct osc_async_page *oap, int cmd)
1248 struct osc_page *opg = oap2osc_page(oap);
1249 pgoff_t index = osc_index(oap2osc(oap));
1250 struct cl_object *obj;
1251 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
1256 /* readpage queues with _COUNT_STABLE, shouldn't get here. */
1257 LASSERT(!(cmd & OBD_BRW_READ));
1258 LASSERT(opg != NULL);
1259 obj = opg->ops_cl.cpl_obj;
1261 cl_object_attr_lock(obj);
1262 result = cl_object_attr_get(env, obj, attr);
1263 cl_object_attr_unlock(obj);
1266 kms = attr->cat_kms;
1267 if (cl_offset(obj, index) >= kms)
1268 /* catch race with truncate */
1270 else if (cl_offset(obj, index + 1) > kms)
1271 /* catch sub-page write at end of file */
1272 return kms % PAGE_CACHE_SIZE;
1274 return PAGE_CACHE_SIZE;
1277 static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
1280 struct osc_page *opg = oap2osc_page(oap);
1281 struct cl_page *page = oap2cl_page(oap);
1282 struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
1283 enum cl_req_type crt;
1288 cmd &= ~OBD_BRW_NOQUOTA;
1289 LASSERTF(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ),
1290 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1291 LASSERTF(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE),
1292 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1293 LASSERT(opg->ops_transfer_pinned);
1296 * page->cp_req can be NULL if io submission failed before
1297 * cl_req was allocated.
1299 if (page->cp_req != NULL)
1300 cl_req_page_done(env, page);
1301 LASSERT(page->cp_req == NULL);
1303 crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
1304 /* Clear opg->ops_transfer_pinned before VM lock is released. */
1305 opg->ops_transfer_pinned = 0;
1307 spin_lock(&obj->oo_seatbelt);
1308 LASSERT(opg->ops_submitter != NULL);
1309 LASSERT(!list_empty(&opg->ops_inflight));
1310 list_del_init(&opg->ops_inflight);
1311 opg->ops_submitter = NULL;
1312 spin_unlock(&obj->oo_seatbelt);
1314 opg->ops_submit_time = 0;
1315 srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
1318 if (rc == 0 && srvlock) {
1319 struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
1320 struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
1321 size_t bytes = oap->oap_count;
1323 if (crt == CRT_READ)
1324 stats->os_lockless_reads += bytes;
1326 stats->os_lockless_writes += bytes;
1330 * This has to be the last operation with the page, as locks are
1331 * released in cl_page_completion() and nothing except for the
1332 * reference counter protects page from concurrent reclaim.
1334 lu_ref_del(&page->cp_reference, "transfer", page);
1336 cl_page_completion(env, page, crt, rc);
1341 #define OSC_DUMP_GRANT(lvl, cli, fmt, args...) do { \
1342 struct client_obd *__tmp = (cli); \
1343 CDEBUG(lvl, "%s: grant { dirty: %ld/%ld dirty_pages: %ld/%lu " \
1344 "dropped: %ld avail: %ld, reserved: %ld, flight: %d }" \
1345 "lru {in list: %ld, left: %ld, waiters: %d }"fmt"\n", \
1346 __tmp->cl_import->imp_obd->obd_name, \
1347 __tmp->cl_dirty_pages, __tmp->cl_dirty_max_pages, \
1348 atomic_long_read(&obd_dirty_pages), obd_max_dirty_pages, \
1349 __tmp->cl_lost_grant, __tmp->cl_avail_grant, \
1350 __tmp->cl_reserved_grant, __tmp->cl_w_in_flight, \
1351 atomic_long_read(&__tmp->cl_lru_in_list), \
1352 atomic_long_read(&__tmp->cl_lru_busy), \
1353 atomic_read(&__tmp->cl_lru_shrinkers), ##args); \
1356 /* caller must hold loi_list_lock */
1357 static void osc_consume_write_grant(struct client_obd *cli,
1358 struct brw_page *pga)
1360 assert_spin_locked(&cli->cl_loi_list_lock);
1361 LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
1362 atomic_long_inc(&obd_dirty_pages);
1363 cli->cl_dirty_pages++;
1364 pga->flag |= OBD_BRW_FROM_GRANT;
1365 CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
1366 PAGE_CACHE_SIZE, pga, pga->pg);
1367 osc_update_next_shrink(cli);
1370 /* the companion to osc_consume_write_grant, called when a brw has completed.
1371 * must be called with the loi lock held. */
1372 static void osc_release_write_grant(struct client_obd *cli,
1373 struct brw_page *pga)
1377 assert_spin_locked(&cli->cl_loi_list_lock);
1378 if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
1383 pga->flag &= ~OBD_BRW_FROM_GRANT;
1384 atomic_long_dec(&obd_dirty_pages);
1385 cli->cl_dirty_pages--;
1386 if (pga->flag & OBD_BRW_NOCACHE) {
1387 pga->flag &= ~OBD_BRW_NOCACHE;
1388 atomic_long_dec(&obd_dirty_transit_pages);
1389 cli->cl_dirty_transit--;
1395 * To avoid sleeping with object lock held, it's good for us allocate enough
1396 * grants before entering into critical section.
1398 * client_obd_list_lock held by caller
1400 static int osc_reserve_grant(struct client_obd *cli, unsigned int bytes)
1404 if (cli->cl_avail_grant >= bytes) {
1405 cli->cl_avail_grant -= bytes;
1406 cli->cl_reserved_grant += bytes;
1412 static void __osc_unreserve_grant(struct client_obd *cli,
1413 unsigned int reserved, unsigned int unused)
1415 /* it's quite normal for us to get more grant than reserved.
1416 * Thinking about a case that two extents merged by adding a new
1417 * chunk, we can save one extent tax. If extent tax is greater than
1418 * one chunk, we can save more grant by adding a new chunk */
1419 cli->cl_reserved_grant -= reserved;
1420 if (unused > reserved) {
1421 cli->cl_avail_grant += reserved;
1422 cli->cl_lost_grant += unused - reserved;
1424 cli->cl_avail_grant += unused;
1428 static void osc_unreserve_grant(struct client_obd *cli,
1429 unsigned int reserved, unsigned int unused)
1431 spin_lock(&cli->cl_loi_list_lock);
1432 __osc_unreserve_grant(cli, reserved, unused);
1434 osc_wake_cache_waiters(cli);
1435 spin_unlock(&cli->cl_loi_list_lock);
1439 * Free grant after IO is finished or canceled.
1441 * @lost_grant is used to remember how many grants we have allocated but not
1442 * used, we should return these grants to OST. There're two cases where grants
1445 * 2. blocksize at OST is less than PAGE_CACHE_SIZE and a partial page was
1446 * written. In this case OST may use less chunks to serve this partial
1447 * write. OSTs don't actually know the page size on the client side. so
1448 * clients have to calculate lost grant by the blocksize on the OST.
1449 * See filter_grant_check() for details.
1451 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
1452 unsigned int lost_grant)
1454 unsigned long grant = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
1456 spin_lock(&cli->cl_loi_list_lock);
1457 atomic_long_sub(nr_pages, &obd_dirty_pages);
1458 cli->cl_dirty_pages -= nr_pages;
1459 cli->cl_lost_grant += lost_grant;
1460 if (cli->cl_avail_grant < grant && cli->cl_lost_grant >= grant) {
1461 /* borrow some grant from truncate to avoid the case that
1462 * truncate uses up all avail grant */
1463 cli->cl_lost_grant -= grant;
1464 cli->cl_avail_grant += grant;
1466 osc_wake_cache_waiters(cli);
1467 spin_unlock(&cli->cl_loi_list_lock);
1468 CDEBUG(D_CACHE, "lost %u grant: %lu avail: %lu dirty: %lu\n",
1469 lost_grant, cli->cl_lost_grant,
1470 cli->cl_avail_grant, cli->cl_dirty_pages << PAGE_CACHE_SHIFT);
1474 * The companion to osc_enter_cache(), called when @oap is no longer part of
1475 * the dirty accounting due to error.
1477 static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap)
1479 spin_lock(&cli->cl_loi_list_lock);
1480 osc_release_write_grant(cli, &oap->oap_brw_page);
1481 spin_unlock(&cli->cl_loi_list_lock);
1485 * Non-blocking version of osc_enter_cache() that consumes grant only when it
1488 static int osc_enter_cache_try(struct client_obd *cli,
1489 struct osc_async_page *oap,
1490 int bytes, int transient)
1494 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1496 rc = osc_reserve_grant(cli, bytes);
1500 if (cli->cl_dirty_pages < cli->cl_dirty_max_pages &&
1501 1 + atomic_long_read(&obd_dirty_pages) <= obd_max_dirty_pages) {
1502 osc_consume_write_grant(cli, &oap->oap_brw_page);
1504 cli->cl_dirty_transit++;
1505 atomic_long_inc(&obd_dirty_transit_pages);
1506 oap->oap_brw_flags |= OBD_BRW_NOCACHE;
1510 __osc_unreserve_grant(cli, bytes, bytes);
1516 static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
1519 spin_lock(&cli->cl_loi_list_lock);
1520 rc = list_empty(&ocw->ocw_entry);
1521 spin_unlock(&cli->cl_loi_list_lock);
1526 * The main entry to reserve dirty page accounting. Usually the grant reserved
1527 * in this function will be freed in bulk in osc_free_grant() unless it fails
1528 * to add osc cache, in that case, it will be freed in osc_exit_cache().
1530 * The process will be put into sleep if it's already run out of grant.
1532 static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
1533 struct osc_async_page *oap, int bytes)
1535 struct osc_object *osc = oap->oap_obj;
1536 struct lov_oinfo *loi = osc->oo_oinfo;
1537 struct osc_cache_waiter ocw;
1538 struct l_wait_info lwi;
1542 lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(AT_OFF ? obd_timeout : at_max),
1543 NULL, LWI_ON_SIGNAL_NOOP, NULL);
1545 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1547 spin_lock(&cli->cl_loi_list_lock);
1549 /* force the caller to try sync io. this can jump the list
1550 * of queued writes and create a discontiguous rpc stream */
1551 if (OBD_FAIL_CHECK(OBD_FAIL_OSC_NO_GRANT) ||
1552 cli->cl_dirty_max_pages == 0 ||
1553 cli->cl_ar.ar_force_sync || loi->loi_ar.ar_force_sync) {
1554 OSC_DUMP_GRANT(D_CACHE, cli, "forced sync i/o\n");
1555 GOTO(out, rc = -EDQUOT);
1558 /* Hopefully normal case - cache space and write credits available */
1559 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1560 OSC_DUMP_GRANT(D_CACHE, cli, "granted from cache\n");
1564 /* We can get here for two reasons: too many dirty pages in cache, or
1565 * run out of grants. In both cases we should write dirty pages out.
1566 * Adding a cache waiter will trigger urgent write-out no matter what
1568 * The exiting condition is no avail grants and no dirty pages caching,
1569 * that really means there is no space on the OST. */
1570 init_waitqueue_head(&ocw.ocw_waitq);
1572 ocw.ocw_grant = bytes;
1573 while (cli->cl_dirty_pages > 0 || cli->cl_w_in_flight > 0) {
1574 list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
1576 spin_unlock(&cli->cl_loi_list_lock);
1578 osc_io_unplug_async(env, cli, NULL);
1580 CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
1581 cli->cl_import->imp_obd->obd_name, &ocw, oap);
1583 rc = l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
1585 spin_lock(&cli->cl_loi_list_lock);
1588 /* l_wait_event is interrupted by signal or timed out */
1589 list_del_init(&ocw.ocw_entry);
1592 LASSERT(list_empty(&ocw.ocw_entry));
1597 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1605 OSC_DUMP_GRANT(D_CACHE, cli, "finally got grant space\n");
1608 OSC_DUMP_GRANT(D_CACHE, cli,
1609 "timeout, fall back to sync i/o\n");
1610 osc_extent_tree_dump(D_CACHE, osc);
1611 /* fall back to synchronous I/O */
1615 /* Ensures restartability - LU-3581 */
1616 OSC_DUMP_GRANT(D_CACHE, cli, "interrupted\n");
1620 OSC_DUMP_GRANT(D_CACHE, cli,
1621 "no grant space, fall back to sync i/o\n");
1624 CDEBUG(D_CACHE, "%s: event for cache space @ %p never arrived "
1625 "due to %d, fall back to sync i/o\n",
1626 cli->cl_import->imp_obd->obd_name, &ocw, rc);
1631 spin_unlock(&cli->cl_loi_list_lock);
1635 /* caller must hold loi_list_lock */
1636 void osc_wake_cache_waiters(struct client_obd *cli)
1638 struct list_head *l, *tmp;
1639 struct osc_cache_waiter *ocw;
1642 list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
1643 ocw = list_entry(l, struct osc_cache_waiter, ocw_entry);
1644 list_del_init(&ocw->ocw_entry);
1646 ocw->ocw_rc = -EDQUOT;
1647 /* we can't dirty more */
1648 if ((cli->cl_dirty_pages >= cli->cl_dirty_max_pages) ||
1649 (1 + atomic_long_read(&obd_dirty_pages) >
1650 obd_max_dirty_pages)) {
1651 CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
1652 "osc max %ld, sys max %ld\n",
1653 cli->cl_dirty_pages, cli->cl_dirty_max_pages,
1654 obd_max_dirty_pages);
1658 if (osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
1661 CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
1662 ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
1664 wake_up(&ocw->ocw_waitq);
1670 static int osc_max_rpc_in_flight(struct client_obd *cli, struct osc_object *osc)
1672 int hprpc = !!list_empty(&osc->oo_hp_exts);
1673 return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
1676 /* This maintains the lists of pending pages to read/write for a given object
1677 * (lop). This is used by osc_check_rpcs->osc_next_obj() and osc_list_maint()
1678 * to quickly find objects that are ready to send an RPC. */
1679 static int osc_makes_rpc(struct client_obd *cli, struct osc_object *osc,
1682 int invalid_import = 0;
1685 /* if we have an invalid import we want to drain the queued pages
1686 * by forcing them through rpcs that immediately fail and complete
1687 * the pages. recovery relies on this to empty the queued pages
1688 * before canceling the locks and evicting down the llite pages */
1689 if ((cli->cl_import == NULL || cli->cl_import->imp_invalid))
1692 if (cmd & OBD_BRW_WRITE) {
1693 if (atomic_read(&osc->oo_nr_writes) == 0)
1695 if (invalid_import) {
1696 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1699 if (!list_empty(&osc->oo_hp_exts)) {
1700 CDEBUG(D_CACHE, "high prio request forcing RPC\n");
1703 if (!list_empty(&osc->oo_urgent_exts)) {
1704 CDEBUG(D_CACHE, "urgent request forcing RPC\n");
1707 /* trigger a write rpc stream as long as there are dirtiers
1708 * waiting for space. as they're waiting, they're not going to
1709 * create more pages to coalesce with what's waiting.. */
1710 if (!list_empty(&cli->cl_cache_waiters)) {
1711 CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
1714 if (atomic_read(&osc->oo_nr_writes) >=
1715 cli->cl_max_pages_per_rpc)
1718 if (atomic_read(&osc->oo_nr_reads) == 0)
1720 if (invalid_import) {
1721 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1724 /* all read are urgent. */
1725 if (!list_empty(&osc->oo_reading_exts))
1732 static void osc_update_pending(struct osc_object *obj, int cmd, int delta)
1734 struct client_obd *cli = osc_cli(obj);
1735 if (cmd & OBD_BRW_WRITE) {
1736 atomic_add(delta, &obj->oo_nr_writes);
1737 atomic_add(delta, &cli->cl_pending_w_pages);
1738 LASSERT(atomic_read(&obj->oo_nr_writes) >= 0);
1740 atomic_add(delta, &obj->oo_nr_reads);
1741 atomic_add(delta, &cli->cl_pending_r_pages);
1742 LASSERT(atomic_read(&obj->oo_nr_reads) >= 0);
1744 OSC_IO_DEBUG(obj, "update pending cmd %d delta %d.\n", cmd, delta);
1747 static int osc_makes_hprpc(struct osc_object *obj)
1749 return !list_empty(&obj->oo_hp_exts);
1752 static void on_list(struct list_head *item, struct list_head *list,
1755 if (list_empty(item) && should_be_on)
1756 list_add_tail(item, list);
1757 else if (!list_empty(item) && !should_be_on)
1758 list_del_init(item);
1761 /* maintain the osc's cli list membership invariants so that osc_send_oap_rpc
1762 * can find pages to build into rpcs quickly */
1763 static int __osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1765 if (osc_makes_hprpc(osc)) {
1767 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list, 0);
1768 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
1770 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
1771 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list,
1772 osc_makes_rpc(cli, osc, OBD_BRW_WRITE) ||
1773 osc_makes_rpc(cli, osc, OBD_BRW_READ));
1776 on_list(&osc->oo_write_item, &cli->cl_loi_write_list,
1777 atomic_read(&osc->oo_nr_writes) > 0);
1779 on_list(&osc->oo_read_item, &cli->cl_loi_read_list,
1780 atomic_read(&osc->oo_nr_reads) > 0);
1782 return osc_is_ready(osc);
1785 static int osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1789 spin_lock(&cli->cl_loi_list_lock);
1790 is_ready = __osc_list_maint(cli, osc);
1791 spin_unlock(&cli->cl_loi_list_lock);
1796 /* this is trying to propogate async writeback errors back up to the
1797 * application. As an async write fails we record the error code for later if
1798 * the app does an fsync. As long as errors persist we force future rpcs to be
1799 * sync so that the app can get a sync error and break the cycle of queueing
1800 * pages for which writeback will fail. */
1801 static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
1808 ar->ar_force_sync = 1;
1809 ar->ar_min_xid = ptlrpc_sample_next_xid();
1814 if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
1815 ar->ar_force_sync = 0;
1818 /* this must be called holding the loi list lock to give coverage to exit_cache,
1819 * async_flag maintenance, and oap_request */
1820 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
1821 struct osc_async_page *oap, int sent, int rc)
1823 struct osc_object *osc = oap->oap_obj;
1824 struct lov_oinfo *loi = osc->oo_oinfo;
1828 if (oap->oap_request != NULL) {
1829 xid = ptlrpc_req_xid(oap->oap_request);
1830 ptlrpc_req_finished(oap->oap_request);
1831 oap->oap_request = NULL;
1834 /* As the transfer for this page is being done, clear the flags */
1835 spin_lock(&oap->oap_lock);
1836 oap->oap_async_flags = 0;
1837 spin_unlock(&oap->oap_lock);
1838 oap->oap_interrupted = 0;
1840 if (oap->oap_cmd & OBD_BRW_WRITE && xid > 0) {
1841 spin_lock(&cli->cl_loi_list_lock);
1842 osc_process_ar(&cli->cl_ar, xid, rc);
1843 osc_process_ar(&loi->loi_ar, xid, rc);
1844 spin_unlock(&cli->cl_loi_list_lock);
1847 rc = osc_completion(env, oap, oap->oap_cmd, rc);
1849 CERROR("completion on oap %p obj %p returns %d.\n",
1856 * Try to add extent to one RPC. We need to think about the following things:
1857 * - # of pages must not be over max_pages_per_rpc
1858 * - extent must be compatible with previous ones
1860 static int try_to_add_extent_for_io(struct client_obd *cli,
1861 struct osc_extent *ext,
1862 struct list_head *rpclist,
1863 unsigned int *pc, unsigned int *max_pages)
1865 struct osc_extent *tmp;
1866 struct osc_async_page *oap = list_first_entry(&ext->oe_pages,
1867 struct osc_async_page,
1871 EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE),
1874 *max_pages = max(ext->oe_mppr, *max_pages);
1875 if (*pc + ext->oe_nr_pages > *max_pages)
1878 list_for_each_entry(tmp, rpclist, oe_link) {
1879 struct osc_async_page *oap2;
1880 oap2 = list_first_entry(&tmp->oe_pages, struct osc_async_page,
1882 EASSERT(tmp->oe_owner == current, tmp);
1884 if (overlapped(tmp, ext)) {
1885 OSC_EXTENT_DUMP(D_ERROR, tmp, "overlapped %p.\n", ext);
1889 if (oap2cl_page(oap)->cp_type != oap2cl_page(oap2)->cp_type) {
1890 CDEBUG(D_CACHE, "Do not permit different type of IO"
1891 " for a same RPC\n");
1895 if (tmp->oe_srvlock != ext->oe_srvlock ||
1896 !tmp->oe_grants != !ext->oe_grants)
1899 /* remove break for strict check */
1903 *pc += ext->oe_nr_pages;
1904 list_move_tail(&ext->oe_link, rpclist);
1905 ext->oe_owner = current;
1910 * In order to prevent multiple ptlrpcd from breaking contiguous extents,
1911 * get_write_extent() takes all appropriate extents in atomic.
1913 * The following policy is used to collect extents for IO:
1914 * 1. Add as many HP extents as possible;
1915 * 2. Add the first urgent extent in urgent extent list and take it out of
1917 * 3. Add subsequent extents of this urgent extent;
1918 * 4. If urgent list is not empty, goto 2;
1919 * 5. Traverse the extent tree from the 1st extent;
1920 * 6. Above steps exit if there is no space in this RPC.
1922 static unsigned int get_write_extents(struct osc_object *obj,
1923 struct list_head *rpclist)
1925 struct client_obd *cli = osc_cli(obj);
1926 struct osc_extent *ext;
1927 unsigned int page_count = 0;
1928 unsigned int max_pages = cli->cl_max_pages_per_rpc;
1930 LASSERT(osc_object_is_locked(obj));
1931 while (!list_empty(&obj->oo_hp_exts)) {
1932 ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
1934 LASSERT(ext->oe_state == OES_CACHE);
1935 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1938 EASSERT(ext->oe_nr_pages <= max_pages, ext);
1940 if (page_count == max_pages)
1943 while (!list_empty(&obj->oo_urgent_exts)) {
1944 ext = list_entry(obj->oo_urgent_exts.next,
1945 struct osc_extent, oe_link);
1946 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1950 if (!ext->oe_intree)
1953 while ((ext = next_extent(ext)) != NULL) {
1954 if ((ext->oe_state != OES_CACHE) ||
1955 (!list_empty(&ext->oe_link) &&
1956 ext->oe_owner != NULL))
1959 if (!try_to_add_extent_for_io(cli, ext, rpclist,
1960 &page_count, &max_pages))
1964 if (page_count == max_pages)
1967 ext = first_extent(obj);
1968 while (ext != NULL) {
1969 if ((ext->oe_state != OES_CACHE) ||
1970 /* this extent may be already in current rpclist */
1971 (!list_empty(&ext->oe_link) && ext->oe_owner != NULL)) {
1972 ext = next_extent(ext);
1976 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1980 ext = next_extent(ext);
1986 osc_send_write_rpc(const struct lu_env *env, struct client_obd *cli,
1987 struct osc_object *osc)
1990 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
1991 struct osc_extent *ext;
1992 struct osc_extent *tmp;
1993 struct osc_extent *first = NULL;
1994 unsigned int page_count = 0;
1999 LASSERT(osc_object_is_locked(osc));
2001 page_count = get_write_extents(osc, &rpclist);
2002 LASSERT(equi(page_count == 0, list_empty(&rpclist)));
2004 if (list_empty(&rpclist))
2007 osc_update_pending(osc, OBD_BRW_WRITE, -page_count);
2009 list_for_each_entry(ext, &rpclist, oe_link) {
2010 LASSERT(ext->oe_state == OES_CACHE ||
2011 ext->oe_state == OES_LOCK_DONE);
2012 if (ext->oe_state == OES_CACHE)
2013 osc_extent_state_set(ext, OES_LOCKING);
2015 osc_extent_state_set(ext, OES_RPC);
2018 /* we're going to grab page lock, so release object lock because
2019 * lock order is page lock -> object lock. */
2020 osc_object_unlock(osc);
2022 list_for_each_entry_safe(ext, tmp, &rpclist, oe_link) {
2023 if (ext->oe_state == OES_LOCKING) {
2024 rc = osc_extent_make_ready(env, ext);
2025 if (unlikely(rc < 0)) {
2026 list_del_init(&ext->oe_link);
2027 osc_extent_finish(env, ext, 0, rc);
2031 if (first == NULL) {
2033 srvlock = ext->oe_srvlock;
2035 LASSERT(srvlock == ext->oe_srvlock);
2039 if (!list_empty(&rpclist)) {
2040 LASSERT(page_count > 0);
2041 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_WRITE);
2042 LASSERT(list_empty(&rpclist));
2045 osc_object_lock(osc);
2050 * prepare pages for ASYNC io and put pages in send queue.
2052 * \param cmd OBD_BRW_* macroses
2053 * \param lop pending pages
2055 * \return zero if no page added to send queue.
2056 * \return 1 if pages successfully added to send queue.
2057 * \return negative on errors.
2060 osc_send_read_rpc(const struct lu_env *env, struct client_obd *cli,
2061 struct osc_object *osc)
2064 struct osc_extent *ext;
2065 struct osc_extent *next;
2066 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2067 unsigned int page_count = 0;
2068 unsigned int max_pages = cli->cl_max_pages_per_rpc;
2072 LASSERT(osc_object_is_locked(osc));
2073 list_for_each_entry_safe(ext, next,
2074 &osc->oo_reading_exts, oe_link) {
2075 EASSERT(ext->oe_state == OES_LOCK_DONE, ext);
2076 if (!try_to_add_extent_for_io(cli, ext, &rpclist, &page_count,
2079 osc_extent_state_set(ext, OES_RPC);
2080 EASSERT(ext->oe_nr_pages <= max_pages, ext);
2082 LASSERT(page_count <= max_pages);
2084 osc_update_pending(osc, OBD_BRW_READ, -page_count);
2086 if (!list_empty(&rpclist)) {
2087 osc_object_unlock(osc);
2089 LASSERT(page_count > 0);
2090 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_READ);
2091 LASSERT(list_empty(&rpclist));
2093 osc_object_lock(osc);
2098 #define list_to_obj(list, item) ({ \
2099 struct list_head *__tmp = (list)->next; \
2100 list_del_init(__tmp); \
2101 list_entry(__tmp, struct osc_object, oo_##item); \
2104 /* This is called by osc_check_rpcs() to find which objects have pages that
2105 * we could be sending. These lists are maintained by osc_makes_rpc(). */
2106 static struct osc_object *osc_next_obj(struct client_obd *cli)
2110 /* First return objects that have blocked locks so that they
2111 * will be flushed quickly and other clients can get the lock,
2112 * then objects which have pages ready to be stuffed into RPCs */
2113 if (!list_empty(&cli->cl_loi_hp_ready_list))
2114 RETURN(list_to_obj(&cli->cl_loi_hp_ready_list, hp_ready_item));
2115 if (!list_empty(&cli->cl_loi_ready_list))
2116 RETURN(list_to_obj(&cli->cl_loi_ready_list, ready_item));
2118 /* then if we have cache waiters, return all objects with queued
2119 * writes. This is especially important when many small files
2120 * have filled up the cache and not been fired into rpcs because
2121 * they don't pass the nr_pending/object threshhold */
2122 if (!list_empty(&cli->cl_cache_waiters) &&
2123 !list_empty(&cli->cl_loi_write_list))
2124 RETURN(list_to_obj(&cli->cl_loi_write_list, write_item));
2126 /* then return all queued objects when we have an invalid import
2127 * so that they get flushed */
2128 if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
2129 if (!list_empty(&cli->cl_loi_write_list))
2130 RETURN(list_to_obj(&cli->cl_loi_write_list,
2132 if (!list_empty(&cli->cl_loi_read_list))
2133 RETURN(list_to_obj(&cli->cl_loi_read_list,
2139 /* called with the loi list lock held */
2140 static void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli)
2141 __must_hold(&cli->cl_loi_list_lock)
2143 struct osc_object *osc;
2147 while ((osc = osc_next_obj(cli)) != NULL) {
2148 struct cl_object *obj = osc2cl(osc);
2149 struct lu_ref_link link;
2151 OSC_IO_DEBUG(osc, "%lu in flight\n", rpcs_in_flight(cli));
2153 if (osc_max_rpc_in_flight(cli, osc)) {
2154 __osc_list_maint(cli, osc);
2159 spin_unlock(&cli->cl_loi_list_lock);
2160 lu_object_ref_add_at(&obj->co_lu, &link, "check", current);
2162 /* attempt some read/write balancing by alternating between
2163 * reads and writes in an object. The makes_rpc checks here
2164 * would be redundant if we were getting read/write work items
2165 * instead of objects. we don't want send_oap_rpc to drain a
2166 * partial read pending queue when we're given this object to
2167 * do io on writes while there are cache waiters */
2168 osc_object_lock(osc);
2169 if (osc_makes_rpc(cli, osc, OBD_BRW_WRITE)) {
2170 rc = osc_send_write_rpc(env, cli, osc);
2172 CERROR("Write request failed with %d\n", rc);
2174 /* osc_send_write_rpc failed, mostly because of
2177 * It can't break here, because if:
2178 * - a page was submitted by osc_io_submit, so
2180 * - no request in flight
2181 * - no subsequent request
2182 * The system will be in live-lock state,
2183 * because there is no chance to call
2184 * osc_io_unplug() and osc_check_rpcs() any
2185 * more. pdflush can't help in this case,
2186 * because it might be blocked at grabbing
2187 * the page lock as we mentioned.
2189 * Anyway, continue to drain pages. */
2193 if (osc_makes_rpc(cli, osc, OBD_BRW_READ)) {
2194 rc = osc_send_read_rpc(env, cli, osc);
2196 CERROR("Read request failed with %d\n", rc);
2198 osc_object_unlock(osc);
2200 osc_list_maint(cli, osc);
2201 lu_object_ref_del_at(&obj->co_lu, &link, "check", current);
2202 cl_object_put(env, obj);
2204 spin_lock(&cli->cl_loi_list_lock);
2208 static int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
2209 struct osc_object *osc, int async)
2213 if (osc != NULL && osc_list_maint(cli, osc) == 0)
2217 /* disable osc_lru_shrink() temporarily to avoid
2218 * potential stack overrun problem. LU-2859 */
2219 atomic_inc(&cli->cl_lru_shrinkers);
2220 spin_lock(&cli->cl_loi_list_lock);
2221 osc_check_rpcs(env, cli);
2222 spin_unlock(&cli->cl_loi_list_lock);
2223 atomic_dec(&cli->cl_lru_shrinkers);
2225 CDEBUG(D_CACHE, "Queue writeback work for client %p.\n", cli);
2226 LASSERT(cli->cl_writeback_work != NULL);
2227 rc = ptlrpcd_queue_work(cli->cl_writeback_work);
2232 static int osc_io_unplug_async(const struct lu_env *env,
2233 struct client_obd *cli, struct osc_object *osc)
2235 return osc_io_unplug0(env, cli, osc, 1);
2238 void osc_io_unplug(const struct lu_env *env, struct client_obd *cli,
2239 struct osc_object *osc)
2241 (void)osc_io_unplug0(env, cli, osc, 0);
2244 int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
2245 struct page *page, loff_t offset)
2247 struct obd_export *exp = osc_export(osc);
2248 struct osc_async_page *oap = &ops->ops_oap;
2252 return cfs_size_round(sizeof(*oap));
2254 oap->oap_magic = OAP_MAGIC;
2255 oap->oap_cli = &exp->exp_obd->u.cli;
2258 oap->oap_page = page;
2259 oap->oap_obj_off = offset;
2260 LASSERT(!(offset & ~PAGE_MASK));
2262 if (!client_is_remote(exp) && cfs_capable(CFS_CAP_SYS_RESOURCE))
2263 oap->oap_brw_flags = OBD_BRW_NOQUOTA;
2265 INIT_LIST_HEAD(&oap->oap_pending_item);
2266 INIT_LIST_HEAD(&oap->oap_rpc_item);
2268 spin_lock_init(&oap->oap_lock);
2269 CDEBUG(D_INFO, "oap %p page %p obj off "LPU64"\n",
2270 oap, page, oap->oap_obj_off);
2274 int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
2275 struct osc_page *ops)
2277 struct osc_io *oio = osc_env_io(env);
2278 struct osc_extent *ext = NULL;
2279 struct osc_async_page *oap = &ops->ops_oap;
2280 struct client_obd *cli = oap->oap_cli;
2281 struct osc_object *osc = oap->oap_obj;
2284 unsigned int grants = 0;
2285 u32 brw_flags = OBD_BRW_ASYNC;
2286 int cmd = OBD_BRW_WRITE;
2287 int need_release = 0;
2291 if (oap->oap_magic != OAP_MAGIC)
2294 if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
2297 if (!list_empty(&oap->oap_pending_item) ||
2298 !list_empty(&oap->oap_rpc_item))
2301 /* Set the OBD_BRW_SRVLOCK before the page is queued. */
2302 brw_flags |= ops->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
2303 if (!client_is_remote(osc_export(osc)) &&
2304 cfs_capable(CFS_CAP_SYS_RESOURCE)) {
2305 brw_flags |= OBD_BRW_NOQUOTA;
2306 cmd |= OBD_BRW_NOQUOTA;
2309 /* check if the file's owner/group is over quota */
2310 if (!(cmd & OBD_BRW_NOQUOTA)) {
2311 struct cl_object *obj;
2312 struct cl_attr *attr;
2313 unsigned int qid[MAXQUOTAS];
2315 obj = cl_object_top(&osc->oo_cl);
2316 attr = &osc_env_info(env)->oti_attr;
2318 cl_object_attr_lock(obj);
2319 rc = cl_object_attr_get(env, obj, attr);
2320 cl_object_attr_unlock(obj);
2322 qid[USRQUOTA] = attr->cat_uid;
2323 qid[GRPQUOTA] = attr->cat_gid;
2324 if (rc == 0 && osc_quota_chkdq(cli, qid) == NO_QUOTA)
2331 oap->oap_page_off = ops->ops_from;
2332 oap->oap_count = ops->ops_to - ops->ops_from;
2333 /* No need to hold a lock here,
2334 * since this page is not in any list yet. */
2335 oap->oap_async_flags = 0;
2336 oap->oap_brw_flags = brw_flags;
2338 OSC_IO_DEBUG(osc, "oap %p page %p added for cmd %d\n",
2339 oap, oap->oap_page, oap->oap_cmd & OBD_BRW_RWMASK);
2341 index = osc_index(oap2osc(oap));
2343 /* Add this page into extent by the following steps:
2344 * 1. if there exists an active extent for this IO, mostly this page
2345 * can be added to the active extent and sometimes we need to
2346 * expand extent to accomodate this page;
2347 * 2. otherwise, a new extent will be allocated. */
2349 ext = oio->oi_active;
2350 if (ext != NULL && ext->oe_start <= index && ext->oe_max_end >= index) {
2351 /* one chunk plus extent overhead must be enough to write this
2353 grants = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
2354 if (ext->oe_end >= index)
2357 /* it doesn't need any grant to dirty this page */
2358 spin_lock(&cli->cl_loi_list_lock);
2359 rc = osc_enter_cache_try(cli, oap, grants, 0);
2360 spin_unlock(&cli->cl_loi_list_lock);
2361 if (rc == 0) { /* try failed */
2364 } else if (ext->oe_end < index) {
2366 /* try to expand this extent */
2367 rc = osc_extent_expand(ext, index, &tmp);
2370 /* don't free reserved grant */
2372 OSC_EXTENT_DUMP(D_CACHE, ext,
2373 "expanded for %lu.\n", index);
2374 osc_unreserve_grant(cli, grants, tmp);
2379 } else if (ext != NULL) {
2380 /* index is located outside of active extent */
2384 osc_extent_release(env, ext);
2385 oio->oi_active = NULL;
2390 tmp = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
2392 /* try to find new extent to cover this page */
2393 LASSERT(oio->oi_active == NULL);
2394 /* we may have allocated grant for this page if we failed
2395 * to expand the previous active extent. */
2396 LASSERT(ergo(grants > 0, grants >= tmp));
2400 /* we haven't allocated grant for this page. */
2401 rc = osc_enter_cache(env, cli, oap, tmp);
2408 ext = osc_extent_find(env, osc, index, &tmp);
2410 LASSERT(tmp == grants);
2411 osc_exit_cache(cli, oap);
2415 oio->oi_active = ext;
2419 osc_unreserve_grant(cli, grants, tmp);
2422 LASSERT(ergo(rc == 0, ext != NULL));
2424 EASSERTF(ext->oe_end >= index && ext->oe_start <= index,
2425 ext, "index = %lu.\n", index);
2426 LASSERT((oap->oap_brw_flags & OBD_BRW_FROM_GRANT) != 0);
2428 osc_object_lock(osc);
2429 if (ext->oe_nr_pages == 0)
2430 ext->oe_srvlock = ops->ops_srvlock;
2432 LASSERT(ext->oe_srvlock == ops->ops_srvlock);
2434 list_add_tail(&oap->oap_pending_item, &ext->oe_pages);
2435 osc_object_unlock(osc);
2440 int osc_teardown_async_page(const struct lu_env *env,
2441 struct osc_object *obj, struct osc_page *ops)
2443 struct osc_async_page *oap = &ops->ops_oap;
2444 struct osc_extent *ext = NULL;
2448 LASSERT(oap->oap_magic == OAP_MAGIC);
2450 CDEBUG(D_INFO, "teardown oap %p page %p at index %lu.\n",
2451 oap, ops, osc_index(oap2osc(oap)));
2453 osc_object_lock(obj);
2454 if (!list_empty(&oap->oap_rpc_item)) {
2455 CDEBUG(D_CACHE, "oap %p is not in cache.\n", oap);
2457 } else if (!list_empty(&oap->oap_pending_item)) {
2458 ext = osc_extent_lookup(obj, osc_index(oap2osc(oap)));
2459 /* only truncated pages are allowed to be taken out.
2460 * See osc_extent_truncate() and osc_cache_truncate_start()
2462 if (ext != NULL && ext->oe_state != OES_TRUNC) {
2463 OSC_EXTENT_DUMP(D_ERROR, ext, "trunc at %lu.\n",
2464 osc_index(oap2osc(oap)));
2468 osc_object_unlock(obj);
2470 osc_extent_put(env, ext);
2475 * This is called when a page is picked up by kernel to write out.
2477 * We should find out the corresponding extent and add the whole extent
2478 * into urgent list. The extent may be being truncated or used, handle it
2481 int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
2482 struct osc_page *ops)
2484 struct osc_extent *ext = NULL;
2485 struct osc_object *obj = cl2osc(ops->ops_cl.cpl_obj);
2486 struct cl_page *cp = ops->ops_cl.cpl_page;
2487 pgoff_t index = osc_index(ops);
2488 struct osc_async_page *oap = &ops->ops_oap;
2489 bool unplug = false;
2493 osc_object_lock(obj);
2494 ext = osc_extent_lookup(obj, index);
2496 osc_extent_tree_dump(D_ERROR, obj);
2497 LASSERTF(0, "page index %lu is NOT covered.\n", index);
2500 switch (ext->oe_state) {
2503 CL_PAGE_DEBUG(D_ERROR, env, cp, "flush an in-rpc page?\n");
2507 /* If we know this extent is being written out, we should abort
2508 * so that the writer can make this page ready. Otherwise, there
2509 * exists a deadlock problem because other process can wait for
2510 * page writeback bit holding page lock; and meanwhile in
2511 * vvp_page_make_ready(), we need to grab page lock before
2512 * really sending the RPC. */
2514 /* race with truncate, page will be redirtied */
2516 /* The extent is active so we need to abort and let the caller
2517 * re-dirty the page. If we continued on here, and we were the
2518 * one making the extent active, we could deadlock waiting for
2519 * the page writeback to clear but it won't because the extent
2520 * is active and won't be written out. */
2521 GOTO(out, rc = -EAGAIN);
2526 rc = cl_page_prep(env, io, cp, CRT_WRITE);
2530 spin_lock(&oap->oap_lock);
2531 oap->oap_async_flags |= ASYNC_READY|ASYNC_URGENT;
2532 spin_unlock(&oap->oap_lock);
2534 if (memory_pressure_get())
2535 ext->oe_memalloc = 1;
2538 if (ext->oe_state == OES_CACHE) {
2539 OSC_EXTENT_DUMP(D_CACHE, ext,
2540 "flush page %p make it urgent.\n", oap);
2541 if (list_empty(&ext->oe_link))
2542 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2549 osc_object_unlock(obj);
2550 osc_extent_put(env, ext);
2552 osc_io_unplug_async(env, osc_cli(obj), obj);
2557 * this is called when a sync waiter receives an interruption. Its job is to
2558 * get the caller woken as soon as possible. If its page hasn't been put in an
2559 * rpc yet it can dequeue immediately. Otherwise it has to mark the rpc as
2560 * desiring interruption which will forcefully complete the rpc once the rpc
2563 int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops)
2565 struct osc_async_page *oap = &ops->ops_oap;
2566 struct osc_object *obj = oap->oap_obj;
2567 struct client_obd *cli = osc_cli(obj);
2568 struct osc_extent *ext;
2569 struct osc_extent *found = NULL;
2570 struct list_head *plist;
2571 pgoff_t index = osc_index(ops);
2576 LASSERT(!oap->oap_interrupted);
2577 oap->oap_interrupted = 1;
2579 /* Find out the caching extent */
2580 osc_object_lock(obj);
2581 if (oap->oap_cmd & OBD_BRW_WRITE) {
2582 plist = &obj->oo_urgent_exts;
2583 cmd = OBD_BRW_WRITE;
2585 plist = &obj->oo_reading_exts;
2588 list_for_each_entry(ext, plist, oe_link) {
2589 if (ext->oe_start <= index && ext->oe_end >= index) {
2590 LASSERT(ext->oe_state == OES_LOCK_DONE);
2591 /* For OES_LOCK_DONE state extent, it has already held
2592 * a refcount for RPC. */
2593 found = osc_extent_get(ext);
2597 if (found != NULL) {
2598 list_del_init(&found->oe_link);
2599 osc_update_pending(obj, cmd, -found->oe_nr_pages);
2600 osc_object_unlock(obj);
2602 osc_extent_finish(env, found, 0, -EINTR);
2603 osc_extent_put(env, found);
2606 osc_object_unlock(obj);
2607 /* ok, it's been put in an rpc. only one oap gets a request
2609 if (oap->oap_request != NULL) {
2610 ptlrpc_mark_interrupted(oap->oap_request);
2611 ptlrpcd_wake(oap->oap_request);
2612 ptlrpc_req_finished(oap->oap_request);
2613 oap->oap_request = NULL;
2617 osc_list_maint(cli, obj);
2621 int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
2622 struct list_head *list, int cmd, int brw_flags)
2624 struct client_obd *cli = osc_cli(obj);
2625 struct osc_extent *ext;
2626 struct osc_async_page *oap;
2628 int mppr = cli->cl_max_pages_per_rpc;
2629 pgoff_t start = CL_PAGE_EOF;
2633 list_for_each_entry(oap, list, oap_pending_item) {
2634 pgoff_t index = osc_index(oap2osc(oap));
2640 mppr <<= (page_count > mppr);
2643 ext = osc_extent_alloc(obj);
2645 struct osc_async_page *tmp;
2647 list_for_each_entry_safe(oap, tmp, list, oap_pending_item) {
2648 list_del_init(&oap->oap_pending_item);
2649 osc_ap_completion(env, cli, oap, 0, -ENOMEM);
2654 ext->oe_rw = !!(cmd & OBD_BRW_READ);
2657 ext->oe_start = start;
2658 ext->oe_end = ext->oe_max_end = end;
2660 ext->oe_srvlock = !!(brw_flags & OBD_BRW_SRVLOCK);
2661 ext->oe_nr_pages = page_count;
2662 ext->oe_mppr = mppr;
2663 list_splice_init(list, &ext->oe_pages);
2665 osc_object_lock(obj);
2666 /* Reuse the initial refcount for RPC, don't drop it */
2667 osc_extent_state_set(ext, OES_LOCK_DONE);
2668 if (cmd & OBD_BRW_WRITE) {
2669 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2670 osc_update_pending(obj, OBD_BRW_WRITE, page_count);
2672 list_add_tail(&ext->oe_link, &obj->oo_reading_exts);
2673 osc_update_pending(obj, OBD_BRW_READ, page_count);
2675 osc_object_unlock(obj);
2677 osc_io_unplug_async(env, cli, obj);
2682 * Called by osc_io_setattr_start() to freeze and destroy covering extents.
2684 int osc_cache_truncate_start(const struct lu_env *env, struct osc_io *oio,
2685 struct osc_object *obj, __u64 size)
2687 struct client_obd *cli = osc_cli(obj);
2688 struct osc_extent *ext;
2689 struct osc_extent *waiting = NULL;
2691 struct list_head list = LIST_HEAD_INIT(list);
2696 /* pages with index greater or equal to index will be truncated. */
2697 index = cl_index(osc2cl(obj), size);
2698 partial = size > cl_offset(osc2cl(obj), index);
2701 osc_object_lock(obj);
2702 ext = osc_extent_search(obj, index);
2704 ext = first_extent(obj);
2705 else if (ext->oe_end < index)
2706 ext = next_extent(ext);
2707 while (ext != NULL) {
2708 EASSERT(ext->oe_state != OES_TRUNC, ext);
2710 if (ext->oe_state > OES_CACHE || ext->oe_urgent) {
2711 /* if ext is in urgent state, it means there must exist
2712 * a page already having been flushed by write_page().
2713 * We have to wait for this extent because we can't
2714 * truncate that page. */
2715 LASSERT(!ext->oe_hp);
2716 OSC_EXTENT_DUMP(D_CACHE, ext,
2717 "waiting for busy extent\n");
2718 waiting = osc_extent_get(ext);
2722 OSC_EXTENT_DUMP(D_CACHE, ext, "try to trunc:"LPU64".\n", size);
2724 osc_extent_get(ext);
2725 if (ext->oe_state == OES_ACTIVE) {
2726 /* though we grab inode mutex for write path, but we
2727 * release it before releasing extent(in osc_io_end()),
2728 * so there is a race window that an extent is still
2729 * in OES_ACTIVE when truncate starts. */
2730 LASSERT(!ext->oe_trunc_pending);
2731 ext->oe_trunc_pending = 1;
2733 EASSERT(ext->oe_state == OES_CACHE, ext);
2734 osc_extent_state_set(ext, OES_TRUNC);
2735 osc_update_pending(obj, OBD_BRW_WRITE,
2738 EASSERT(list_empty(&ext->oe_link), ext);
2739 list_add_tail(&ext->oe_link, &list);
2741 ext = next_extent(ext);
2743 osc_object_unlock(obj);
2745 osc_list_maint(cli, obj);
2747 while (!list_empty(&list)) {
2750 ext = list_entry(list.next, struct osc_extent, oe_link);
2751 list_del_init(&ext->oe_link);
2753 /* extent may be in OES_ACTIVE state because inode mutex
2754 * is released before osc_io_end() in file write case */
2755 if (ext->oe_state != OES_TRUNC)
2756 osc_extent_wait(env, ext, OES_TRUNC);
2758 rc = osc_extent_truncate(ext, index, partial);
2763 OSC_EXTENT_DUMP(D_ERROR, ext,
2764 "truncate error %d\n", rc);
2765 } else if (ext->oe_nr_pages == 0) {
2766 osc_extent_remove(ext);
2768 /* this must be an overlapped extent which means only
2769 * part of pages in this extent have been truncated.
2771 EASSERTF(ext->oe_start <= index, ext,
2772 "trunc index = %lu/%d.\n", index, partial);
2773 /* fix index to skip this partially truncated extent */
2774 index = ext->oe_end + 1;
2777 /* we need to hold this extent in OES_TRUNC state so
2778 * that no writeback will happen. This is to avoid
2780 LASSERT(oio->oi_trunc == NULL);
2781 oio->oi_trunc = osc_extent_get(ext);
2782 OSC_EXTENT_DUMP(D_CACHE, ext,
2783 "trunc at "LPU64"\n", size);
2785 osc_extent_put(env, ext);
2787 if (waiting != NULL) {
2790 /* ignore the result of osc_extent_wait the write initiator
2791 * should take care of it. */
2792 rc = osc_extent_wait(env, waiting, OES_INV);
2794 OSC_EXTENT_DUMP(D_CACHE, waiting, "error: %d.\n", rc);
2796 osc_extent_put(env, waiting);
2804 * Called after osc_io_setattr_end to add oio->oi_trunc back to cache.
2806 void osc_cache_truncate_end(const struct lu_env *env, struct osc_io *oio,
2807 struct osc_object *obj)
2809 struct osc_extent *ext = oio->oi_trunc;
2811 oio->oi_trunc = NULL;
2813 bool unplug = false;
2815 EASSERT(ext->oe_nr_pages > 0, ext);
2816 EASSERT(ext->oe_state == OES_TRUNC, ext);
2817 EASSERT(!ext->oe_urgent, ext);
2819 OSC_EXTENT_DUMP(D_CACHE, ext, "trunc -> cache.\n");
2820 osc_object_lock(obj);
2821 osc_extent_state_set(ext, OES_CACHE);
2822 if (ext->oe_fsync_wait && !ext->oe_urgent) {
2824 list_move_tail(&ext->oe_link, &obj->oo_urgent_exts);
2827 osc_update_pending(obj, OBD_BRW_WRITE, ext->oe_nr_pages);
2828 osc_object_unlock(obj);
2829 osc_extent_put(env, ext);
2832 osc_io_unplug_async(env, osc_cli(obj), obj);
2837 * Wait for extents in a specific range to be written out.
2838 * The caller must have called osc_cache_writeback_range() to issue IO
2839 * otherwise it will take a long time for this function to finish.
2841 * Caller must hold inode_mutex , or cancel exclusive dlm lock so that
2842 * nobody else can dirty this range of file while we're waiting for
2843 * extents to be written.
2845 int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
2846 pgoff_t start, pgoff_t end)
2848 struct osc_extent *ext;
2849 pgoff_t index = start;
2854 osc_object_lock(obj);
2855 ext = osc_extent_search(obj, index);
2857 ext = first_extent(obj);
2858 else if (ext->oe_end < index)
2859 ext = next_extent(ext);
2860 while (ext != NULL) {
2863 if (ext->oe_start > end)
2866 if (!ext->oe_fsync_wait) {
2867 ext = next_extent(ext);
2871 EASSERT(ergo(ext->oe_state == OES_CACHE,
2872 ext->oe_hp || ext->oe_urgent), ext);
2873 EASSERT(ergo(ext->oe_state == OES_ACTIVE,
2874 !ext->oe_hp && ext->oe_urgent), ext);
2876 index = ext->oe_end + 1;
2877 osc_extent_get(ext);
2878 osc_object_unlock(obj);
2880 rc = osc_extent_wait(env, ext, OES_INV);
2883 osc_extent_put(env, ext);
2886 osc_object_unlock(obj);
2888 OSC_IO_DEBUG(obj, "sync file range.\n");
2893 * Called to write out a range of osc object.
2895 * @hp : should be set this is caused by lock cancel;
2896 * @discard: is set if dirty pages should be dropped - file will be deleted or
2897 * truncated, this implies there is no partially discarding extents.
2899 * Return how many pages will be issued, or error code if error occurred.
2901 int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
2902 pgoff_t start, pgoff_t end, int hp, int discard)
2904 struct osc_extent *ext;
2905 struct list_head discard_list = LIST_HEAD_INIT(discard_list);
2906 bool unplug = false;
2910 osc_object_lock(obj);
2911 ext = osc_extent_search(obj, start);
2913 ext = first_extent(obj);
2914 else if (ext->oe_end < start)
2915 ext = next_extent(ext);
2916 while (ext != NULL) {
2917 if (ext->oe_start > end)
2920 ext->oe_fsync_wait = 1;
2921 switch (ext->oe_state) {
2923 result += ext->oe_nr_pages;
2925 struct list_head *list = NULL;
2927 EASSERT(!ext->oe_hp, ext);
2929 list = &obj->oo_hp_exts;
2930 } else if (!ext->oe_urgent) {
2932 list = &obj->oo_urgent_exts;
2935 list_move_tail(&ext->oe_link, list);
2938 /* the only discarder is lock cancelling, so
2939 * [start, end] must contain this extent */
2940 EASSERT(ext->oe_start >= start &&
2941 ext->oe_max_end <= end, ext);
2942 osc_extent_state_set(ext, OES_LOCKING);
2943 ext->oe_owner = current;
2944 list_move_tail(&ext->oe_link,
2946 osc_update_pending(obj, OBD_BRW_WRITE,
2951 /* It's pretty bad to wait for ACTIVE extents, because
2952 * we don't know how long we will wait for it to be
2953 * flushed since it may be blocked at awaiting more
2954 * grants. We do this for the correctness of fsync. */
2955 LASSERT(hp == 0 && discard == 0);
2959 /* this extent is being truncated, can't do anything
2960 * for it now. it will be set to urgent after truncate
2961 * is finished in osc_cache_truncate_end(). */
2965 ext = next_extent(ext);
2967 osc_object_unlock(obj);
2969 LASSERT(ergo(!discard, list_empty(&discard_list)));
2970 if (!list_empty(&discard_list)) {
2971 struct osc_extent *tmp;
2974 osc_list_maint(osc_cli(obj), obj);
2975 list_for_each_entry_safe(ext, tmp, &discard_list, oe_link) {
2976 list_del_init(&ext->oe_link);
2977 EASSERT(ext->oe_state == OES_LOCKING, ext);
2979 /* Discard caching pages. We don't actually write this
2980 * extent out but we complete it as if we did. */
2981 rc = osc_extent_make_ready(env, ext);
2982 if (unlikely(rc < 0)) {
2983 OSC_EXTENT_DUMP(D_ERROR, ext,
2984 "make_ready returned %d\n", rc);
2989 /* finish the extent as if the pages were sent */
2990 osc_extent_finish(env, ext, 0, 0);
2995 osc_io_unplug(env, osc_cli(obj), obj);
2997 if (hp || discard) {
2999 rc = osc_cache_wait_range(env, obj, start, end);
3000 if (result >= 0 && rc < 0)
3004 OSC_IO_DEBUG(obj, "pageout [%lu, %lu], %d.\n", start, end, result);
3009 * Returns a list of pages by a given [start, end] of \a obj.
3011 * \param resched If not NULL, then we give up before hogging CPU for too
3012 * long and set *resched = 1, in that case caller should implement a retry
3015 * Gang tree lookup (radix_tree_gang_lookup()) optimization is absolutely
3016 * crucial in the face of [offset, EOF] locks.
3018 * Return at least one page in @queue unless there is no covered page.
3020 int osc_page_gang_lookup(const struct lu_env *env, struct cl_io *io,
3021 struct osc_object *osc, pgoff_t start, pgoff_t end,
3022 osc_page_gang_cbt cb, void *cbdata)
3024 struct osc_page *ops;
3030 int res = CLP_GANG_OKAY;
3031 bool tree_lock = true;
3035 pvec = osc_env_info(env)->oti_pvec;
3036 spin_lock(&osc->oo_tree_lock);
3037 while ((nr = radix_tree_gang_lookup(&osc->oo_tree, pvec,
3038 idx, OTI_PVEC_SIZE)) > 0) {
3039 struct cl_page *page;
3040 bool end_of_region = false;
3042 for (i = 0, j = 0; i < nr; ++i) {
3046 idx = osc_index(ops);
3048 end_of_region = true;
3052 page = ops->ops_cl.cpl_page;
3053 LASSERT(page->cp_type == CPT_CACHEABLE);
3054 if (page->cp_state == CPS_FREEING)
3058 lu_ref_add_atomic(&page->cp_reference,
3059 "gang_lookup", current);
3065 * Here a delicate locking dance is performed. Current thread
3066 * holds a reference to a page, but has to own it before it
3067 * can be placed into queue. Owning implies waiting, so
3068 * radix-tree lock is to be released. After a wait one has to
3069 * check that pages weren't truncated (cl_page_own() returns
3070 * error in the latter case).
3072 spin_unlock(&osc->oo_tree_lock);
3075 for (i = 0; i < j; ++i) {
3077 if (res == CLP_GANG_OKAY)
3078 res = (*cb)(env, io, ops, cbdata);
3080 page = ops->ops_cl.cpl_page;
3081 lu_ref_del(&page->cp_reference, "gang_lookup", current);
3082 cl_page_put(env, page);
3084 if (nr < OTI_PVEC_SIZE || end_of_region)
3087 if (res == CLP_GANG_OKAY && need_resched())
3088 res = CLP_GANG_RESCHED;
3089 if (res != CLP_GANG_OKAY)
3092 spin_lock(&osc->oo_tree_lock);
3096 spin_unlock(&osc->oo_tree_lock);
3101 * Check if page @page is covered by an extra lock or discard it.
3103 static int check_and_discard_cb(const struct lu_env *env, struct cl_io *io,
3104 struct osc_page *ops, void *cbdata)
3106 struct osc_thread_info *info = osc_env_info(env);
3107 struct osc_object *osc = cbdata;
3110 index = osc_index(ops);
3111 if (index >= info->oti_fn_index) {
3112 struct ldlm_lock *tmp;
3113 struct cl_page *page = ops->ops_cl.cpl_page;
3115 /* refresh non-overlapped index */
3116 tmp = osc_dlmlock_at_pgoff(env, osc, index,
3117 OSC_DAP_FL_TEST_LOCK);
3119 __u64 end = tmp->l_policy_data.l_extent.end;
3120 /* Cache the first-non-overlapped index so as to skip
3121 * all pages within [index, oti_fn_index). This is safe
3122 * because if tmp lock is canceled, it will discard
3124 info->oti_fn_index = cl_index(osc2cl(osc), end + 1);
3125 if (end == OBD_OBJECT_EOF)
3126 info->oti_fn_index = CL_PAGE_EOF;
3128 } else if (cl_page_own(env, io, page) == 0) {
3129 /* discard the page */
3130 cl_page_discard(env, io, page);
3131 cl_page_disown(env, io, page);
3133 LASSERT(page->cp_state == CPS_FREEING);
3137 info->oti_next_index = index + 1;
3138 return CLP_GANG_OKAY;
3141 static int discard_cb(const struct lu_env *env, struct cl_io *io,
3142 struct osc_page *ops, void *cbdata)
3144 struct osc_thread_info *info = osc_env_info(env);
3145 struct cl_page *page = ops->ops_cl.cpl_page;
3147 /* page is top page. */
3148 info->oti_next_index = osc_index(ops) + 1;
3149 if (cl_page_own(env, io, page) == 0) {
3150 KLASSERT(ergo(page->cp_type == CPT_CACHEABLE,
3151 !PageDirty(cl_page_vmpage(page))));
3153 /* discard the page */
3154 cl_page_discard(env, io, page);
3155 cl_page_disown(env, io, page);
3157 LASSERT(page->cp_state == CPS_FREEING);
3160 return CLP_GANG_OKAY;
3164 * Discard pages protected by the given lock. This function traverses radix
3165 * tree to find all covering pages and discard them. If a page is being covered
3166 * by other locks, it should remain in cache.
3168 * If error happens on any step, the process continues anyway (the reasoning
3169 * behind this being that lock cancellation cannot be delayed indefinitely).
3171 int osc_lock_discard_pages(const struct lu_env *env, struct osc_object *osc,
3172 pgoff_t start, pgoff_t end, enum cl_lock_mode mode)
3174 struct osc_thread_info *info = osc_env_info(env);
3175 struct cl_io *io = &info->oti_io;
3176 osc_page_gang_cbt cb;
3182 io->ci_obj = cl_object_top(osc2cl(osc));
3183 io->ci_ignore_layout = 1;
3184 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
3188 cb = mode == CLM_READ ? check_and_discard_cb : discard_cb;
3189 info->oti_fn_index = info->oti_next_index = start;
3191 res = osc_page_gang_lookup(env, io, osc,
3192 info->oti_next_index, end, cb, osc);
3193 if (info->oti_next_index > end)
3196 if (res == CLP_GANG_RESCHED)
3198 } while (res != CLP_GANG_OKAY);
3200 cl_io_fini(env, io);