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.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
26 * Copyright (c) 2012, 2015, Intel Corporation.
30 * This file is part of Lustre, http://www.lustre.org/
31 * Lustre is a trademark of Sun Microsystems, Inc.
33 * osc cache management.
35 * Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
38 #define DEBUG_SUBSYSTEM S_OSC
40 #include "osc_cl_internal.h"
41 #include "osc_internal.h"
43 static int extent_debug; /* set it to be true for more debug */
45 static void osc_update_pending(struct osc_object *obj, int cmd, int delta);
46 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
47 enum osc_extent_state state);
48 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
49 struct osc_async_page *oap, int sent, int rc);
50 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
52 static int osc_refresh_count(const struct lu_env *env,
53 struct osc_async_page *oap, int cmd);
54 static int osc_io_unplug_async(const struct lu_env *env,
55 struct client_obd *cli, struct osc_object *osc);
56 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
57 unsigned int lost_grant, unsigned int dirty_grant);
59 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
60 const char *func, int line);
61 #define osc_extent_tree_dump(lvl, obj) \
62 osc_extent_tree_dump0(lvl, obj, __func__, __LINE__)
64 static void osc_unreserve_grant(struct client_obd *cli, unsigned int reserved,
71 /* ------------------ osc extent ------------------ */
72 static inline char *ext_flags(struct osc_extent *ext, char *flags)
75 *buf++ = ext->oe_rw ? 'r' : 'w';
88 if (ext->oe_trunc_pending)
90 if (ext->oe_fsync_wait)
96 static inline char list_empty_marker(struct list_head *list)
98 return list_empty(list) ? '-' : '+';
101 #define EXTSTR "[%lu -> %lu/%lu]"
102 #define EXTPARA(ext) (ext)->oe_start, (ext)->oe_end, (ext)->oe_max_end
103 static const char *oes_strings[] = {
104 "inv", "active", "cache", "locking", "lockdone", "rpc", "trunc", NULL };
106 #define OSC_EXTENT_DUMP(lvl, extent, fmt, ...) do { \
107 struct osc_extent *__ext = (extent); \
111 "extent %p@{" EXTSTR ", " \
112 "[%d|%d|%c|%s|%s|%p], [%d|%d|%c|%c|%p|%u|%p]} " fmt, \
113 /* ----- extent part 0 ----- */ \
114 __ext, EXTPARA(__ext), \
115 /* ----- part 1 ----- */ \
116 atomic_read(&__ext->oe_refc), \
117 atomic_read(&__ext->oe_users), \
118 list_empty_marker(&__ext->oe_link), \
119 oes_strings[__ext->oe_state], ext_flags(__ext, __buf), \
121 /* ----- part 2 ----- */ \
122 __ext->oe_grants, __ext->oe_nr_pages, \
123 list_empty_marker(&__ext->oe_pages), \
124 waitqueue_active(&__ext->oe_waitq) ? '+' : '-', \
125 __ext->oe_dlmlock, __ext->oe_mppr, __ext->oe_owner, \
126 /* ----- part 4 ----- */ \
128 if (lvl == D_ERROR && __ext->oe_dlmlock != NULL) \
129 LDLM_ERROR(__ext->oe_dlmlock, "extent: %p", __ext); \
131 LDLM_DEBUG(__ext->oe_dlmlock, "extent: %p", __ext); \
135 #define EASSERTF(expr, ext, fmt, args...) do { \
137 OSC_EXTENT_DUMP(D_ERROR, (ext), fmt, ##args); \
138 osc_extent_tree_dump(D_ERROR, (ext)->oe_obj); \
144 #define EASSERT(expr, ext) EASSERTF(expr, ext, "\n")
146 static inline struct osc_extent *rb_extent(struct rb_node *n)
151 return container_of(n, struct osc_extent, oe_node);
154 static inline struct osc_extent *next_extent(struct osc_extent *ext)
159 LASSERT(ext->oe_intree);
160 return rb_extent(rb_next(&ext->oe_node));
163 static inline struct osc_extent *prev_extent(struct osc_extent *ext)
168 LASSERT(ext->oe_intree);
169 return rb_extent(rb_prev(&ext->oe_node));
172 static inline struct osc_extent *first_extent(struct osc_object *obj)
174 return rb_extent(rb_first(&obj->oo_root));
177 /* object must be locked by caller. */
178 static int osc_extent_sanity_check0(struct osc_extent *ext,
179 const char *func, const int line)
181 struct osc_object *obj = ext->oe_obj;
182 struct osc_async_page *oap;
186 if (!osc_object_is_locked(obj))
189 if (ext->oe_state >= OES_STATE_MAX)
192 if (atomic_read(&ext->oe_refc) <= 0)
195 if (atomic_read(&ext->oe_refc) < atomic_read(&ext->oe_users))
198 switch (ext->oe_state) {
200 if (ext->oe_nr_pages > 0 || !list_empty(&ext->oe_pages))
205 if (atomic_read(&ext->oe_users) == 0)
209 if (ext->oe_fsync_wait && !ext->oe_urgent)
213 if (ext->oe_grants == 0)
215 if (ext->oe_fsync_wait && !ext->oe_urgent && !ext->oe_hp)
218 if (atomic_read(&ext->oe_users) > 0)
222 if (ext->oe_max_end < ext->oe_end || ext->oe_end < ext->oe_start)
225 if (ext->oe_sync && ext->oe_grants > 0)
228 if (ext->oe_dlmlock != NULL && !ldlm_is_failed(ext->oe_dlmlock)) {
229 struct ldlm_extent *extent;
231 extent = &ext->oe_dlmlock->l_policy_data.l_extent;
232 if (!(extent->start <= cl_offset(osc2cl(obj), ext->oe_start) &&
233 extent->end >= cl_offset(osc2cl(obj), ext->oe_max_end)))
236 if (!(ext->oe_dlmlock->l_granted_mode & (LCK_PW | LCK_GROUP)))
240 if (ext->oe_nr_pages > ext->oe_mppr)
243 /* Do not verify page list if extent is in RPC. This is because an
244 * in-RPC extent is supposed to be exclusively accessible w/o lock. */
245 if (ext->oe_state > OES_CACHE)
252 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
253 pgoff_t index = osc_index(oap2osc(oap));
255 if (index > ext->oe_end || index < ext->oe_start)
258 if (page_count != ext->oe_nr_pages)
263 OSC_EXTENT_DUMP(D_ERROR, ext,
264 "%s:%d sanity check %p failed with rc = %d\n",
265 func, line, ext, rc);
269 #define sanity_check_nolock(ext) \
270 osc_extent_sanity_check0(ext, __func__, __LINE__)
272 #define sanity_check(ext) ({ \
274 osc_object_lock((ext)->oe_obj); \
275 __res = sanity_check_nolock(ext); \
276 osc_object_unlock((ext)->oe_obj); \
282 * sanity check - to make sure there is no overlapped extent in the tree.
284 static int osc_extent_is_overlapped(struct osc_object *obj,
285 struct osc_extent *ext)
287 struct osc_extent *tmp;
289 LASSERT(osc_object_is_locked(obj));
294 for (tmp = first_extent(obj); tmp != NULL; tmp = next_extent(tmp)) {
297 if (tmp->oe_end >= ext->oe_start &&
298 tmp->oe_start <= ext->oe_end)
304 static void osc_extent_state_set(struct osc_extent *ext, int state)
306 LASSERT(osc_object_is_locked(ext->oe_obj));
307 LASSERT(state >= OES_INV && state < OES_STATE_MAX);
309 /* Never try to sanity check a state changing extent :-) */
310 /* LASSERT(sanity_check_nolock(ext) == 0); */
312 /* TODO: validate the state machine */
313 ext->oe_state = state;
314 wake_up_all(&ext->oe_waitq);
317 static struct osc_extent *osc_extent_alloc(struct osc_object *obj)
319 struct osc_extent *ext;
321 OBD_SLAB_ALLOC_PTR_GFP(ext, osc_extent_kmem, GFP_NOFS);
325 RB_CLEAR_NODE(&ext->oe_node);
327 cl_object_get(osc2cl(obj));
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 cl_object_put(env, osc2cl(ext->oe_obj));
367 osc_extent_free(ext);
372 * osc_extent_put_trust() is a special version of osc_extent_put() when
373 * it's known that the caller is not the last user. This is to address the
374 * problem of lacking of lu_env ;-).
376 static void osc_extent_put_trust(struct osc_extent *ext)
378 LASSERT(atomic_read(&ext->oe_refc) > 1);
379 LASSERT(osc_object_is_locked(ext->oe_obj));
380 atomic_dec(&ext->oe_refc);
384 * Return the extent which includes pgoff @index, or return the greatest
385 * previous extent in the tree.
387 static struct osc_extent *osc_extent_search(struct osc_object *obj,
390 struct rb_node *n = obj->oo_root.rb_node;
391 struct osc_extent *tmp, *p = NULL;
393 LASSERT(osc_object_is_locked(obj));
396 if (index < tmp->oe_start) {
398 } else if (index > tmp->oe_end) {
409 * Return the extent covering @index, otherwise return NULL.
410 * caller must have held object lock.
412 static struct osc_extent *osc_extent_lookup(struct osc_object *obj,
415 struct osc_extent *ext;
417 ext = osc_extent_search(obj, index);
418 if (ext != NULL && ext->oe_start <= index && index <= ext->oe_end)
419 return osc_extent_get(ext);
423 /* caller must have held object lock. */
424 static void osc_extent_insert(struct osc_object *obj, struct osc_extent *ext)
426 struct rb_node **n = &obj->oo_root.rb_node;
427 struct rb_node *parent = NULL;
428 struct osc_extent *tmp;
430 LASSERT(ext->oe_intree == 0);
431 LASSERT(ext->oe_obj == obj);
432 LASSERT(osc_object_is_locked(obj));
437 if (ext->oe_end < tmp->oe_start)
439 else if (ext->oe_start > tmp->oe_end)
442 EASSERTF(0, tmp, EXTSTR"\n", EXTPARA(ext));
444 rb_link_node(&ext->oe_node, parent, n);
445 rb_insert_color(&ext->oe_node, &obj->oo_root);
450 /* caller must have held object lock. */
451 static void osc_extent_erase(struct osc_extent *ext)
453 struct osc_object *obj = ext->oe_obj;
454 LASSERT(osc_object_is_locked(obj));
455 if (ext->oe_intree) {
456 rb_erase(&ext->oe_node, &obj->oo_root);
458 /* rbtree held a refcount */
459 osc_extent_put_trust(ext);
463 static struct osc_extent *osc_extent_hold(struct osc_extent *ext)
465 struct osc_object *obj = ext->oe_obj;
467 LASSERT(osc_object_is_locked(obj));
468 LASSERT(ext->oe_state == OES_ACTIVE || ext->oe_state == OES_CACHE);
469 if (ext->oe_state == OES_CACHE) {
470 osc_extent_state_set(ext, OES_ACTIVE);
471 osc_update_pending(obj, OBD_BRW_WRITE, -ext->oe_nr_pages);
473 atomic_inc(&ext->oe_users);
474 list_del_init(&ext->oe_link);
475 return osc_extent_get(ext);
478 static void __osc_extent_remove(struct osc_extent *ext)
480 LASSERT(osc_object_is_locked(ext->oe_obj));
481 LASSERT(list_empty(&ext->oe_pages));
482 osc_extent_erase(ext);
483 list_del_init(&ext->oe_link);
484 osc_extent_state_set(ext, OES_INV);
485 OSC_EXTENT_DUMP(D_CACHE, ext, "destroyed.\n");
488 static void osc_extent_remove(struct osc_extent *ext)
490 struct osc_object *obj = ext->oe_obj;
492 osc_object_lock(obj);
493 __osc_extent_remove(ext);
494 osc_object_unlock(obj);
498 * This function is used to merge extents to get better performance. It checks
499 * if @cur and @victim are contiguous at block level.
501 static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
502 struct osc_extent *victim)
504 struct osc_object *obj = cur->oe_obj;
505 struct client_obd *cli = osc_cli(obj);
510 LASSERT(cur->oe_state == OES_CACHE);
511 LASSERT(osc_object_is_locked(obj));
515 if (victim->oe_state != OES_CACHE || victim->oe_fsync_wait)
518 if (cur->oe_max_end != victim->oe_max_end)
521 LASSERT(cur->oe_dlmlock == victim->oe_dlmlock);
522 ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_SHIFT;
523 chunk_start = cur->oe_start >> ppc_bits;
524 chunk_end = cur->oe_end >> ppc_bits;
525 if (chunk_start != (victim->oe_end >> ppc_bits) + 1 &&
526 chunk_end + 1 != victim->oe_start >> ppc_bits)
529 /* overall extent size should not exceed the max supported limit
530 * reported by the server */
531 if (cur->oe_end - cur->oe_start + 1 +
532 victim->oe_end - victim->oe_start + 1 > cli->cl_max_extent_pages)
535 OSC_EXTENT_DUMP(D_CACHE, victim, "will be merged by %p.\n", cur);
537 cur->oe_start = min(cur->oe_start, victim->oe_start);
538 cur->oe_end = max(cur->oe_end, victim->oe_end);
539 /* per-extent tax should be accounted only once for the whole extent */
540 cur->oe_grants += victim->oe_grants - cli->cl_grant_extent_tax;
541 cur->oe_nr_pages += victim->oe_nr_pages;
542 /* only the following bits are needed to merge */
543 cur->oe_urgent |= victim->oe_urgent;
544 cur->oe_memalloc |= victim->oe_memalloc;
545 list_splice_init(&victim->oe_pages, &cur->oe_pages);
546 list_del_init(&victim->oe_link);
547 victim->oe_nr_pages = 0;
549 osc_extent_get(victim);
550 __osc_extent_remove(victim);
551 osc_extent_put(env, victim);
553 OSC_EXTENT_DUMP(D_CACHE, cur, "after merging %p.\n", victim);
558 * Drop user count of osc_extent, and unplug IO asynchronously.
560 int osc_extent_release(const struct lu_env *env, struct osc_extent *ext)
562 struct osc_object *obj = ext->oe_obj;
563 struct client_obd *cli = osc_cli(obj);
567 LASSERT(atomic_read(&ext->oe_users) > 0);
568 LASSERT(sanity_check(ext) == 0);
569 LASSERT(ext->oe_grants > 0);
571 if (atomic_dec_and_lock(&ext->oe_users, &obj->oo_lock)) {
572 LASSERT(ext->oe_state == OES_ACTIVE);
573 if (ext->oe_trunc_pending) {
574 /* a truncate process is waiting for this extent.
575 * This may happen due to a race, check
576 * osc_cache_truncate_start(). */
577 osc_extent_state_set(ext, OES_TRUNC);
578 ext->oe_trunc_pending = 0;
582 osc_extent_state_set(ext, OES_CACHE);
583 osc_update_pending(obj, OBD_BRW_WRITE,
586 /* try to merge the previous and next extent. */
587 if (osc_extent_merge(env, ext, prev_extent(ext)) == 0)
588 grant += cli->cl_grant_extent_tax;
589 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
590 grant += cli->cl_grant_extent_tax;
592 osc_unreserve_grant(cli, 0, grant);
595 list_move_tail(&ext->oe_link,
596 &obj->oo_urgent_exts);
597 else if (ext->oe_nr_pages == ext->oe_mppr) {
598 list_move_tail(&ext->oe_link,
602 osc_object_unlock(obj);
604 osc_io_unplug_async(env, cli, obj);
606 osc_extent_put(env, ext);
610 static inline int overlapped(struct osc_extent *ex1, struct osc_extent *ex2)
612 return !(ex1->oe_end < ex2->oe_start || ex2->oe_end < ex1->oe_start);
616 * Find or create an extent which includes @index, core function to manage
619 static struct osc_extent *osc_extent_find(const struct lu_env *env,
620 struct osc_object *obj, pgoff_t index,
621 unsigned int *grants)
623 struct client_obd *cli = osc_cli(obj);
624 struct osc_lock *olck;
625 struct cl_lock_descr *descr;
626 struct osc_extent *cur;
627 struct osc_extent *ext;
628 struct osc_extent *conflict = NULL;
629 struct osc_extent *found = NULL;
632 unsigned int max_pages; /* max_pages_per_rpc */
633 unsigned int chunksize;
634 int ppc_bits; /* pages per chunk bits */
639 cur = osc_extent_alloc(obj);
641 RETURN(ERR_PTR(-ENOMEM));
643 olck = osc_env_io(env)->oi_write_osclock;
644 LASSERTF(olck != NULL, "page %lu is not covered by lock\n", index);
645 LASSERT(olck->ols_state == OLS_GRANTED);
647 descr = &olck->ols_cl.cls_lock->cll_descr;
648 LASSERT(descr->cld_mode >= CLM_WRITE);
650 LASSERTF(cli->cl_chunkbits >= PAGE_SHIFT,
651 "chunkbits: %u\n", cli->cl_chunkbits);
652 ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
653 chunk_mask = ~((1 << ppc_bits) - 1);
654 chunksize = 1 << cli->cl_chunkbits;
655 chunk = index >> ppc_bits;
657 /* align end to RPC edge. */
658 max_pages = cli->cl_max_pages_per_rpc;
659 if ((max_pages & ~chunk_mask) != 0) {
660 CERROR("max_pages: %#x chunkbits: %u chunk_mask: %#lx\n",
661 max_pages, cli->cl_chunkbits, chunk_mask);
662 RETURN(ERR_PTR(-EINVAL));
664 max_end = index - (index % max_pages) + max_pages - 1;
665 max_end = min_t(pgoff_t, max_end, descr->cld_end);
667 /* initialize new extent by parameters so far */
668 cur->oe_max_end = max_end;
669 cur->oe_start = index & chunk_mask;
670 cur->oe_end = ((index + ~chunk_mask + 1) & chunk_mask) - 1;
671 if (cur->oe_start < descr->cld_start)
672 cur->oe_start = descr->cld_start;
673 if (cur->oe_end > max_end)
674 cur->oe_end = max_end;
676 cur->oe_mppr = max_pages;
677 if (olck->ols_dlmlock != NULL) {
678 LASSERT(olck->ols_hold);
679 cur->oe_dlmlock = LDLM_LOCK_GET(olck->ols_dlmlock);
680 lu_ref_add(&olck->ols_dlmlock->l_reference, "osc_extent", cur);
683 /* grants has been allocated by caller */
684 LASSERTF(*grants >= chunksize + cli->cl_grant_extent_tax,
685 "%u/%u/%u.\n", *grants, chunksize, cli->cl_grant_extent_tax);
686 LASSERTF((max_end - cur->oe_start) < max_pages, EXTSTR"\n",
690 osc_object_lock(obj);
691 ext = osc_extent_search(obj, cur->oe_start);
693 ext = first_extent(obj);
694 while (ext != NULL) {
695 pgoff_t ext_chk_start = ext->oe_start >> ppc_bits;
696 pgoff_t ext_chk_end = ext->oe_end >> ppc_bits;
698 LASSERT(sanity_check_nolock(ext) == 0);
699 if (chunk > ext_chk_end + 1)
702 /* if covering by different locks, no chance to match */
703 if (olck->ols_dlmlock != ext->oe_dlmlock) {
704 EASSERTF(!overlapped(ext, cur), ext,
705 EXTSTR"\n", EXTPARA(cur));
707 ext = next_extent(ext);
711 /* discontiguous chunks? */
712 if (chunk + 1 < ext_chk_start) {
713 ext = next_extent(ext);
717 /* ok, from now on, ext and cur have these attrs:
718 * 1. covered by the same lock
719 * 2. contiguous at chunk level or overlapping. */
721 if (overlapped(ext, cur)) {
722 /* cur is the minimum unit, so overlapping means
724 EASSERTF((ext->oe_start <= cur->oe_start &&
725 ext->oe_end >= cur->oe_end),
726 ext, EXTSTR"\n", EXTPARA(cur));
728 if (ext->oe_state > OES_CACHE || ext->oe_fsync_wait) {
729 /* for simplicity, we wait for this extent to
730 * finish before going forward. */
731 conflict = osc_extent_get(ext);
735 found = osc_extent_hold(ext);
739 /* non-overlapped extent */
740 if (ext->oe_state != OES_CACHE || ext->oe_fsync_wait) {
741 /* we can't do anything for a non OES_CACHE extent, or
742 * if there is someone waiting for this extent to be
743 * flushed, try next one. */
744 ext = next_extent(ext);
748 /* check if they belong to the same rpc slot before trying to
749 * merge. the extents are not overlapped and contiguous at
750 * chunk level to get here. */
751 if (ext->oe_max_end != max_end) {
752 /* if they don't belong to the same RPC slot or
753 * max_pages_per_rpc has ever changed, do not merge. */
754 ext = next_extent(ext);
758 /* check whether maximum extent size will be hit */
759 if ((ext_chk_end - ext_chk_start + 1 + 1) << ppc_bits >
760 cli->cl_max_extent_pages) {
761 ext = next_extent(ext);
765 /* it's required that an extent must be contiguous at chunk
766 * level so that we know the whole extent is covered by grant
767 * (the pages in the extent are NOT required to be contiguous).
768 * Otherwise, it will be too much difficult to know which
769 * chunks have grants allocated. */
771 /* try to do front merge - extend ext's start */
772 if (chunk + 1 == ext_chk_start) {
773 /* ext must be chunk size aligned */
774 EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
776 /* pull ext's start back to cover cur */
777 ext->oe_start = cur->oe_start;
778 ext->oe_grants += chunksize;
779 *grants -= chunksize;
781 found = osc_extent_hold(ext);
782 } else if (chunk == ext_chk_end + 1) {
784 ext->oe_end = cur->oe_end;
785 ext->oe_grants += chunksize;
786 *grants -= chunksize;
788 /* try to merge with the next one because we just fill
790 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
791 /* we can save extent tax from next extent */
792 *grants += cli->cl_grant_extent_tax;
794 found = osc_extent_hold(ext);
799 ext = next_extent(ext);
802 osc_extent_tree_dump(D_CACHE, obj);
804 LASSERT(conflict == NULL);
805 if (!IS_ERR(found)) {
806 LASSERT(found->oe_dlmlock == cur->oe_dlmlock);
807 OSC_EXTENT_DUMP(D_CACHE, found,
808 "found caching ext for %lu.\n", index);
810 } else if (conflict == NULL) {
811 /* create a new extent */
812 EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
813 cur->oe_grants = chunksize + cli->cl_grant_extent_tax;
814 *grants -= cur->oe_grants;
815 LASSERT(*grants >= 0);
817 cur->oe_state = OES_CACHE;
818 found = osc_extent_hold(cur);
819 osc_extent_insert(obj, cur);
820 OSC_EXTENT_DUMP(D_CACHE, cur, "add into tree %lu/%lu.\n",
821 index, descr->cld_end);
823 osc_object_unlock(obj);
825 if (conflict != NULL) {
826 LASSERT(found == NULL);
828 /* waiting for IO to finish. Please notice that it's impossible
829 * to be an OES_TRUNC extent. */
830 rc = osc_extent_wait(env, conflict, OES_INV);
831 osc_extent_put(env, conflict);
834 GOTO(out, found = ERR_PTR(rc));
841 osc_extent_put(env, cur);
842 LASSERT(*grants >= 0);
847 * Called when IO is finished to an extent.
849 int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
852 struct client_obd *cli = osc_cli(ext->oe_obj);
853 struct osc_async_page *oap;
854 struct osc_async_page *tmp;
855 int nr_pages = ext->oe_nr_pages;
857 int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
862 OSC_EXTENT_DUMP(D_CACHE, ext, "extent finished.\n");
864 ext->oe_rc = rc ?: ext->oe_nr_pages;
865 EASSERT(ergo(rc == 0, ext->oe_state == OES_RPC), ext);
867 osc_lru_add_batch(cli, &ext->oe_pages);
868 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
870 list_del_init(&oap->oap_rpc_item);
871 list_del_init(&oap->oap_pending_item);
872 if (last_off <= oap->oap_obj_off) {
873 last_off = oap->oap_obj_off;
874 last_count = oap->oap_count;
878 osc_ap_completion(env, cli, oap, sent, rc);
880 EASSERT(ext->oe_nr_pages == 0, ext);
883 lost_grant = ext->oe_grants;
884 } else if (blocksize < PAGE_SIZE &&
885 last_count != PAGE_SIZE) {
886 /* For short writes we shouldn't count parts of pages that
887 * span a whole chunk on the OST side, or our accounting goes
888 * wrong. Should match the code in filter_grant_check. */
889 int offset = last_off & ~PAGE_MASK;
890 int count = last_count + (offset & (blocksize - 1));
891 int end = (offset + last_count) & (blocksize - 1);
893 count += blocksize - end;
895 lost_grant = PAGE_SIZE - count;
897 if (ext->oe_grants > 0)
898 osc_free_grant(cli, nr_pages, lost_grant, ext->oe_grants);
900 osc_extent_remove(ext);
901 /* put the refcount for RPC */
902 osc_extent_put(env, ext);
906 static int extent_wait_cb(struct osc_extent *ext, enum osc_extent_state state)
910 osc_object_lock(ext->oe_obj);
911 ret = ext->oe_state == state;
912 osc_object_unlock(ext->oe_obj);
918 * Wait for the extent's state to become @state.
920 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
921 enum osc_extent_state state)
923 struct osc_object *obj = ext->oe_obj;
924 struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(600), NULL,
925 LWI_ON_SIGNAL_NOOP, NULL);
929 osc_object_lock(obj);
930 LASSERT(sanity_check_nolock(ext) == 0);
931 /* `Kick' this extent only if the caller is waiting for it to be
933 if (state == OES_INV && !ext->oe_urgent && !ext->oe_hp) {
934 if (ext->oe_state == OES_ACTIVE) {
936 } else if (ext->oe_state == OES_CACHE) {
938 osc_extent_hold(ext);
942 osc_object_unlock(obj);
944 osc_extent_release(env, ext);
946 /* wait for the extent until its state becomes @state */
947 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state), &lwi);
948 if (rc == -ETIMEDOUT) {
949 OSC_EXTENT_DUMP(D_ERROR, ext,
950 "%s: wait ext to %u timedout, recovery in progress?\n",
951 cli_name(osc_cli(obj)), state);
953 lwi = LWI_INTR(NULL, NULL);
954 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state),
957 if (rc == 0 && ext->oe_rc < 0)
963 * Discard pages with index greater than @size. If @ext is overlapped with
964 * @size, then partial truncate happens.
966 static int osc_extent_truncate(struct osc_extent *ext, pgoff_t trunc_index,
971 struct osc_object *obj = ext->oe_obj;
972 struct client_obd *cli = osc_cli(obj);
973 struct osc_async_page *oap;
974 struct osc_async_page *tmp;
975 int pages_in_chunk = 0;
976 int ppc_bits = cli->cl_chunkbits -
978 __u64 trunc_chunk = trunc_index >> ppc_bits;
985 LASSERT(sanity_check(ext) == 0);
986 LASSERT(ext->oe_state == OES_TRUNC);
987 LASSERT(!ext->oe_urgent);
989 /* Request new lu_env.
990 * We can't use that env from osc_cache_truncate_start() because
991 * it's from lov_io_sub and not fully initialized. */
992 env = cl_env_get(&refcheck);
993 io = &osc_env_info(env)->oti_io;
994 io->ci_obj = cl_object_top(osc2cl(obj));
995 io->ci_ignore_layout = 1;
996 rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
1000 /* discard all pages with index greater than trunc_index */
1001 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
1003 pgoff_t index = osc_index(oap2osc(oap));
1004 struct cl_page *page = oap2cl_page(oap);
1006 LASSERT(list_empty(&oap->oap_rpc_item));
1008 /* only discard the pages with their index greater than
1009 * trunc_index, and ... */
1010 if (index < trunc_index ||
1011 (index == trunc_index && partial)) {
1012 /* accounting how many pages remaining in the chunk
1013 * so that we can calculate grants correctly. */
1014 if (index >> ppc_bits == trunc_chunk)
1019 list_del_init(&oap->oap_pending_item);
1022 lu_ref_add(&page->cp_reference, "truncate", current);
1024 if (cl_page_own(env, io, page) == 0) {
1025 cl_page_discard(env, io, page);
1026 cl_page_disown(env, io, page);
1028 LASSERT(page->cp_state == CPS_FREEING);
1032 lu_ref_del(&page->cp_reference, "truncate", current);
1033 cl_page_put(env, page);
1038 EASSERTF(ergo(ext->oe_start >= trunc_index + !!partial,
1039 ext->oe_nr_pages == 0),
1040 ext, "trunc_index %lu, partial %d\n", trunc_index, partial);
1042 osc_object_lock(obj);
1043 if (ext->oe_nr_pages == 0) {
1044 LASSERT(pages_in_chunk == 0);
1045 grants = ext->oe_grants;
1047 } else { /* calculate how many grants we can free */
1048 int chunks = (ext->oe_end >> ppc_bits) - trunc_chunk;
1052 /* if there is no pages in this chunk, we can also free grants
1053 * for the last chunk */
1054 if (pages_in_chunk == 0) {
1055 /* if this is the 1st chunk and no pages in this chunk,
1056 * ext->oe_nr_pages must be zero, so we should be in
1057 * the other if-clause. */
1058 LASSERT(trunc_chunk > 0);
1063 /* this is what we can free from this extent */
1064 grants = chunks << cli->cl_chunkbits;
1065 ext->oe_grants -= grants;
1066 last_index = ((trunc_chunk + 1) << ppc_bits) - 1;
1067 ext->oe_end = min(last_index, ext->oe_max_end);
1068 LASSERT(ext->oe_end >= ext->oe_start);
1069 LASSERT(ext->oe_grants > 0);
1071 osc_object_unlock(obj);
1073 if (grants > 0 || nr_pages > 0)
1074 osc_free_grant(cli, nr_pages, grants, grants);
1077 cl_io_fini(env, io);
1078 cl_env_put(env, &refcheck);
1083 * This function is used to make the extent prepared for transfer.
1084 * A race with flusing page - ll_writepage() has to be handled cautiously.
1086 static int osc_extent_make_ready(const struct lu_env *env,
1087 struct osc_extent *ext)
1089 struct osc_async_page *oap;
1090 struct osc_async_page *last = NULL;
1091 struct osc_object *obj = ext->oe_obj;
1092 unsigned int page_count = 0;
1096 /* we're going to grab page lock, so object lock must not be taken. */
1097 LASSERT(sanity_check(ext) == 0);
1098 /* in locking state, any process should not touch this extent. */
1099 EASSERT(ext->oe_state == OES_LOCKING, ext);
1100 EASSERT(ext->oe_owner != NULL, ext);
1102 OSC_EXTENT_DUMP(D_CACHE, ext, "make ready\n");
1104 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1106 if (last == NULL || last->oap_obj_off < oap->oap_obj_off)
1109 /* checking ASYNC_READY is race safe */
1110 if ((oap->oap_async_flags & ASYNC_READY) != 0)
1113 rc = osc_make_ready(env, oap, OBD_BRW_WRITE);
1116 spin_lock(&oap->oap_lock);
1117 oap->oap_async_flags |= ASYNC_READY;
1118 spin_unlock(&oap->oap_lock);
1121 LASSERT((oap->oap_async_flags & ASYNC_READY) != 0);
1124 LASSERTF(0, "unknown return code: %d\n", rc);
1128 LASSERT(page_count == ext->oe_nr_pages);
1129 LASSERT(last != NULL);
1130 /* the last page is the only one we need to refresh its count by
1131 * the size of file. */
1132 if (!(last->oap_async_flags & ASYNC_COUNT_STABLE)) {
1133 int last_oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE);
1134 LASSERT(last_oap_count > 0);
1135 LASSERT(last->oap_page_off + last_oap_count <= PAGE_SIZE);
1136 last->oap_count = last_oap_count;
1137 spin_lock(&last->oap_lock);
1138 last->oap_async_flags |= ASYNC_COUNT_STABLE;
1139 spin_unlock(&last->oap_lock);
1142 /* for the rest of pages, we don't need to call osf_refresh_count()
1143 * because it's known they are not the last page */
1144 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1145 if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
1146 oap->oap_count = PAGE_SIZE - oap->oap_page_off;
1147 spin_lock(&oap->oap_lock);
1148 oap->oap_async_flags |= ASYNC_COUNT_STABLE;
1149 spin_unlock(&oap->oap_lock);
1153 osc_object_lock(obj);
1154 osc_extent_state_set(ext, OES_RPC);
1155 osc_object_unlock(obj);
1156 /* get a refcount for RPC. */
1157 osc_extent_get(ext);
1163 * Quick and simple version of osc_extent_find(). This function is frequently
1164 * called to expand the extent for the same IO. To expand the extent, the
1165 * page index must be in the same or next chunk of ext->oe_end.
1167 static int osc_extent_expand(struct osc_extent *ext, pgoff_t index,
1168 unsigned int *grants)
1170 struct osc_object *obj = ext->oe_obj;
1171 struct client_obd *cli = osc_cli(obj);
1172 struct osc_extent *next;
1173 int ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
1174 pgoff_t chunk = index >> ppc_bits;
1177 unsigned int chunksize = 1 << cli->cl_chunkbits;
1181 LASSERT(ext->oe_max_end >= index && ext->oe_start <= index);
1182 osc_object_lock(obj);
1183 LASSERT(sanity_check_nolock(ext) == 0);
1184 end_chunk = ext->oe_end >> ppc_bits;
1185 if (chunk > end_chunk + 1)
1186 GOTO(out, rc = -ERANGE);
1188 if (end_chunk >= chunk)
1191 LASSERT(end_chunk + 1 == chunk);
1193 /* try to expand this extent to cover @index */
1194 end_index = min(ext->oe_max_end, ((chunk + 1) << ppc_bits) - 1);
1196 /* don't go over the maximum extent size reported by server */
1197 if (end_index - ext->oe_start + 1 > cli->cl_max_extent_pages)
1198 GOTO(out, rc = -ERANGE);
1200 next = next_extent(ext);
1201 if (next != NULL && next->oe_start <= end_index)
1202 /* complex mode - overlapped with the next extent,
1203 * this case will be handled by osc_extent_find() */
1204 GOTO(out, rc = -EAGAIN);
1206 ext->oe_end = end_index;
1207 ext->oe_grants += chunksize;
1208 *grants -= chunksize;
1209 LASSERT(*grants >= 0);
1210 EASSERTF(osc_extent_is_overlapped(obj, ext) == 0, ext,
1211 "overlapped after expanding for %lu.\n", index);
1215 osc_object_unlock(obj);
1219 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
1220 const char *func, int line)
1222 struct osc_extent *ext;
1225 CDEBUG(level, "Dump object %p extents at %s:%d, mppr: %u.\n",
1226 obj, func, line, osc_cli(obj)->cl_max_pages_per_rpc);
1228 /* osc_object_lock(obj); */
1230 for (ext = first_extent(obj); ext != NULL; ext = next_extent(ext))
1231 OSC_EXTENT_DUMP(level, ext, "in tree %d.\n", cnt++);
1234 list_for_each_entry(ext, &obj->oo_hp_exts, oe_link)
1235 OSC_EXTENT_DUMP(level, ext, "hp %d.\n", cnt++);
1238 list_for_each_entry(ext, &obj->oo_urgent_exts, oe_link)
1239 OSC_EXTENT_DUMP(level, ext, "urgent %d.\n", cnt++);
1242 list_for_each_entry(ext, &obj->oo_reading_exts, oe_link)
1243 OSC_EXTENT_DUMP(level, ext, "reading %d.\n", cnt++);
1244 /* osc_object_unlock(obj); */
1247 /* ------------------ osc extent end ------------------ */
1249 static inline int osc_is_ready(struct osc_object *osc)
1251 return !list_empty(&osc->oo_ready_item) ||
1252 !list_empty(&osc->oo_hp_ready_item);
1255 #define OSC_IO_DEBUG(OSC, STR, args...) \
1256 CDEBUG(D_CACHE, "obj %p ready %d|%c|%c wr %d|%c|%c rd %d|%c " STR, \
1257 (OSC), osc_is_ready(OSC), \
1258 list_empty_marker(&(OSC)->oo_hp_ready_item), \
1259 list_empty_marker(&(OSC)->oo_ready_item), \
1260 atomic_read(&(OSC)->oo_nr_writes), \
1261 list_empty_marker(&(OSC)->oo_hp_exts), \
1262 list_empty_marker(&(OSC)->oo_urgent_exts), \
1263 atomic_read(&(OSC)->oo_nr_reads), \
1264 list_empty_marker(&(OSC)->oo_reading_exts), \
1267 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
1270 struct osc_page *opg = oap2osc_page(oap);
1271 struct cl_page *page = oap2cl_page(oap);
1274 LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
1277 result = cl_page_make_ready(env, page, CRT_WRITE);
1279 opg->ops_submit_time = cfs_time_current();
1283 static int osc_refresh_count(const struct lu_env *env,
1284 struct osc_async_page *oap, int cmd)
1286 struct osc_page *opg = oap2osc_page(oap);
1287 pgoff_t index = osc_index(oap2osc(oap));
1288 struct cl_object *obj;
1289 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
1294 /* readpage queues with _COUNT_STABLE, shouldn't get here. */
1295 LASSERT(!(cmd & OBD_BRW_READ));
1296 LASSERT(opg != NULL);
1297 obj = opg->ops_cl.cpl_obj;
1299 cl_object_attr_lock(obj);
1300 result = cl_object_attr_get(env, obj, attr);
1301 cl_object_attr_unlock(obj);
1304 kms = attr->cat_kms;
1305 if (cl_offset(obj, index) >= kms)
1306 /* catch race with truncate */
1308 else if (cl_offset(obj, index + 1) > kms)
1309 /* catch sub-page write at end of file */
1310 return kms % PAGE_SIZE;
1315 static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
1318 struct osc_page *opg = oap2osc_page(oap);
1319 struct cl_page *page = oap2cl_page(oap);
1320 enum cl_req_type crt;
1325 cmd &= ~OBD_BRW_NOQUOTA;
1326 LASSERTF(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ),
1327 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1328 LASSERTF(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE),
1329 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1330 LASSERT(opg->ops_transfer_pinned);
1332 crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
1333 /* Clear opg->ops_transfer_pinned before VM lock is released. */
1334 opg->ops_transfer_pinned = 0;
1336 opg->ops_submit_time = 0;
1337 srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
1340 if (rc == 0 && srvlock) {
1341 struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
1342 struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
1343 size_t bytes = oap->oap_count;
1345 if (crt == CRT_READ)
1346 stats->os_lockless_reads += bytes;
1348 stats->os_lockless_writes += bytes;
1352 * This has to be the last operation with the page, as locks are
1353 * released in cl_page_completion() and nothing except for the
1354 * reference counter protects page from concurrent reclaim.
1356 lu_ref_del(&page->cp_reference, "transfer", page);
1358 cl_page_completion(env, page, crt, rc);
1359 cl_page_put(env, page);
1364 #define OSC_DUMP_GRANT(lvl, cli, fmt, args...) do { \
1365 struct client_obd *__tmp = (cli); \
1366 CDEBUG(lvl, "%s: grant { dirty: %ld/%ld dirty_pages: %ld/%lu " \
1367 "dropped: %ld avail: %ld, dirty_grant: %ld, " \
1368 "reserved: %ld, flight: %d } lru {in list: %ld, " \
1369 "left: %ld, waiters: %d }" fmt "\n", \
1371 __tmp->cl_dirty_pages, __tmp->cl_dirty_max_pages, \
1372 atomic_long_read(&obd_dirty_pages), obd_max_dirty_pages, \
1373 __tmp->cl_lost_grant, __tmp->cl_avail_grant, \
1374 __tmp->cl_dirty_grant, \
1375 __tmp->cl_reserved_grant, __tmp->cl_w_in_flight, \
1376 atomic_long_read(&__tmp->cl_lru_in_list), \
1377 atomic_long_read(&__tmp->cl_lru_busy), \
1378 atomic_read(&__tmp->cl_lru_shrinkers), ##args); \
1381 /* caller must hold loi_list_lock */
1382 static void osc_consume_write_grant(struct client_obd *cli,
1383 struct brw_page *pga)
1385 assert_spin_locked(&cli->cl_loi_list_lock);
1386 LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
1387 atomic_long_inc(&obd_dirty_pages);
1388 cli->cl_dirty_pages++;
1389 pga->flag |= OBD_BRW_FROM_GRANT;
1390 CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
1391 PAGE_SIZE, pga, pga->pg);
1392 osc_update_next_shrink(cli);
1395 /* the companion to osc_consume_write_grant, called when a brw has completed.
1396 * must be called with the loi lock held. */
1397 static void osc_release_write_grant(struct client_obd *cli,
1398 struct brw_page *pga)
1402 assert_spin_locked(&cli->cl_loi_list_lock);
1403 if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
1408 pga->flag &= ~OBD_BRW_FROM_GRANT;
1409 atomic_long_dec(&obd_dirty_pages);
1410 cli->cl_dirty_pages--;
1411 if (pga->flag & OBD_BRW_NOCACHE) {
1412 pga->flag &= ~OBD_BRW_NOCACHE;
1413 atomic_long_dec(&obd_dirty_transit_pages);
1414 cli->cl_dirty_transit--;
1420 * To avoid sleeping with object lock held, it's good for us allocate enough
1421 * grants before entering into critical section.
1423 * client_obd_list_lock held by caller
1425 static int osc_reserve_grant(struct client_obd *cli, unsigned int bytes)
1429 if (cli->cl_avail_grant >= bytes) {
1430 cli->cl_avail_grant -= bytes;
1431 cli->cl_reserved_grant += bytes;
1437 static void __osc_unreserve_grant(struct client_obd *cli,
1438 unsigned int reserved, unsigned int unused)
1440 /* it's quite normal for us to get more grant than reserved.
1441 * Thinking about a case that two extents merged by adding a new
1442 * chunk, we can save one extent tax. If extent tax is greater than
1443 * one chunk, we can save more grant by adding a new chunk */
1444 cli->cl_reserved_grant -= reserved;
1445 if (unused > reserved) {
1446 cli->cl_avail_grant += reserved;
1447 cli->cl_lost_grant += unused - reserved;
1448 cli->cl_dirty_grant -= unused - reserved;
1450 cli->cl_avail_grant += unused;
1451 cli->cl_dirty_grant += reserved - unused;
1455 static void osc_unreserve_grant(struct client_obd *cli,
1456 unsigned int reserved, unsigned int unused)
1458 spin_lock(&cli->cl_loi_list_lock);
1459 __osc_unreserve_grant(cli, reserved, unused);
1461 osc_wake_cache_waiters(cli);
1462 spin_unlock(&cli->cl_loi_list_lock);
1466 * Free grant after IO is finished or canceled.
1468 * @lost_grant is used to remember how many grants we have allocated but not
1469 * used, we should return these grants to OST. There're two cases where grants
1472 * 2. blocksize at OST is less than PAGE_SIZE and a partial page was
1473 * written. In this case OST may use less chunks to serve this partial
1474 * write. OSTs don't actually know the page size on the client side. so
1475 * clients have to calculate lost grant by the blocksize on the OST.
1476 * See filter_grant_check() for details.
1478 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
1479 unsigned int lost_grant, unsigned int dirty_grant)
1481 unsigned long grant;
1483 grant = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
1485 spin_lock(&cli->cl_loi_list_lock);
1486 atomic_long_sub(nr_pages, &obd_dirty_pages);
1487 cli->cl_dirty_pages -= nr_pages;
1488 cli->cl_lost_grant += lost_grant;
1489 cli->cl_dirty_grant -= dirty_grant;
1490 if (cli->cl_avail_grant < grant && cli->cl_lost_grant >= grant) {
1491 /* borrow some grant from truncate to avoid the case that
1492 * truncate uses up all avail grant */
1493 cli->cl_lost_grant -= grant;
1494 cli->cl_avail_grant += grant;
1496 osc_wake_cache_waiters(cli);
1497 spin_unlock(&cli->cl_loi_list_lock);
1498 CDEBUG(D_CACHE, "lost %u grant: %lu avail: %lu dirty: %lu/%lu\n",
1499 lost_grant, cli->cl_lost_grant,
1500 cli->cl_avail_grant, cli->cl_dirty_pages << PAGE_SHIFT,
1501 cli->cl_dirty_grant);
1505 * The companion to osc_enter_cache(), called when @oap is no longer part of
1506 * the dirty accounting due to error.
1508 static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap)
1510 spin_lock(&cli->cl_loi_list_lock);
1511 osc_release_write_grant(cli, &oap->oap_brw_page);
1512 spin_unlock(&cli->cl_loi_list_lock);
1516 * Non-blocking version of osc_enter_cache() that consumes grant only when it
1519 static int osc_enter_cache_try(struct client_obd *cli,
1520 struct osc_async_page *oap,
1521 int bytes, int transient)
1525 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1527 rc = osc_reserve_grant(cli, bytes);
1531 if (cli->cl_dirty_pages < cli->cl_dirty_max_pages &&
1532 1 + atomic_long_read(&obd_dirty_pages) <= obd_max_dirty_pages) {
1533 osc_consume_write_grant(cli, &oap->oap_brw_page);
1535 cli->cl_dirty_transit++;
1536 atomic_long_inc(&obd_dirty_transit_pages);
1537 oap->oap_brw_flags |= OBD_BRW_NOCACHE;
1541 __osc_unreserve_grant(cli, bytes, bytes);
1547 static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
1550 spin_lock(&cli->cl_loi_list_lock);
1551 rc = list_empty(&ocw->ocw_entry);
1552 spin_unlock(&cli->cl_loi_list_lock);
1557 * The main entry to reserve dirty page accounting. Usually the grant reserved
1558 * in this function will be freed in bulk in osc_free_grant() unless it fails
1559 * to add osc cache, in that case, it will be freed in osc_exit_cache().
1561 * The process will be put into sleep if it's already run out of grant.
1563 static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
1564 struct osc_async_page *oap, int bytes)
1566 struct osc_object *osc = oap->oap_obj;
1567 struct lov_oinfo *loi = osc->oo_oinfo;
1568 struct osc_cache_waiter ocw;
1569 struct l_wait_info lwi;
1573 lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(AT_OFF ? obd_timeout : at_max),
1574 NULL, LWI_ON_SIGNAL_NOOP, NULL);
1576 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1578 spin_lock(&cli->cl_loi_list_lock);
1580 /* force the caller to try sync io. this can jump the list
1581 * of queued writes and create a discontiguous rpc stream */
1582 if (OBD_FAIL_CHECK(OBD_FAIL_OSC_NO_GRANT) ||
1583 cli->cl_dirty_max_pages == 0 ||
1584 cli->cl_ar.ar_force_sync || loi->loi_ar.ar_force_sync) {
1585 OSC_DUMP_GRANT(D_CACHE, cli, "forced sync i/o\n");
1586 GOTO(out, rc = -EDQUOT);
1589 /* Hopefully normal case - cache space and write credits available */
1590 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1591 OSC_DUMP_GRANT(D_CACHE, cli, "granted from cache\n");
1595 /* We can get here for two reasons: too many dirty pages in cache, or
1596 * run out of grants. In both cases we should write dirty pages out.
1597 * Adding a cache waiter will trigger urgent write-out no matter what
1599 * The exiting condition is no avail grants and no dirty pages caching,
1600 * that really means there is no space on the OST. */
1601 init_waitqueue_head(&ocw.ocw_waitq);
1603 ocw.ocw_grant = bytes;
1604 while (cli->cl_dirty_pages > 0 || cli->cl_w_in_flight > 0) {
1605 list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
1607 spin_unlock(&cli->cl_loi_list_lock);
1609 osc_io_unplug_async(env, cli, NULL);
1611 CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
1612 cli_name(cli), &ocw, oap);
1614 rc = l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
1616 spin_lock(&cli->cl_loi_list_lock);
1619 /* l_wait_event is interrupted by signal or timed out */
1620 list_del_init(&ocw.ocw_entry);
1623 LASSERT(list_empty(&ocw.ocw_entry));
1628 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1636 OSC_DUMP_GRANT(D_CACHE, cli, "finally got grant space\n");
1639 OSC_DUMP_GRANT(D_CACHE, cli,
1640 "timeout, fall back to sync i/o\n");
1641 osc_extent_tree_dump(D_CACHE, osc);
1642 /* fall back to synchronous I/O */
1646 /* Ensures restartability - LU-3581 */
1647 OSC_DUMP_GRANT(D_CACHE, cli, "interrupted\n");
1651 OSC_DUMP_GRANT(D_CACHE, cli,
1652 "no grant space, fall back to sync i/o\n");
1655 CDEBUG(D_CACHE, "%s: event for cache space @ %p never arrived "
1656 "due to %d, fall back to sync i/o\n",
1657 cli_name(cli), &ocw, rc);
1662 spin_unlock(&cli->cl_loi_list_lock);
1666 /* caller must hold loi_list_lock */
1667 void osc_wake_cache_waiters(struct client_obd *cli)
1669 struct list_head *l, *tmp;
1670 struct osc_cache_waiter *ocw;
1673 list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
1674 ocw = list_entry(l, struct osc_cache_waiter, ocw_entry);
1675 list_del_init(&ocw->ocw_entry);
1677 ocw->ocw_rc = -EDQUOT;
1678 /* we can't dirty more */
1679 if ((cli->cl_dirty_pages >= cli->cl_dirty_max_pages) ||
1680 (1 + atomic_long_read(&obd_dirty_pages) >
1681 obd_max_dirty_pages)) {
1682 CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
1683 "osc max %ld, sys max %ld\n",
1684 cli->cl_dirty_pages, cli->cl_dirty_max_pages,
1685 obd_max_dirty_pages);
1689 if (osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
1692 CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
1693 ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
1695 wake_up(&ocw->ocw_waitq);
1701 static int osc_max_rpc_in_flight(struct client_obd *cli, struct osc_object *osc)
1703 int hprpc = !!list_empty(&osc->oo_hp_exts);
1704 return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
1707 /* This maintains the lists of pending pages to read/write for a given object
1708 * (lop). This is used by osc_check_rpcs->osc_next_obj() and osc_list_maint()
1709 * to quickly find objects that are ready to send an RPC. */
1710 static int osc_makes_rpc(struct client_obd *cli, struct osc_object *osc,
1713 int invalid_import = 0;
1716 /* if we have an invalid import we want to drain the queued pages
1717 * by forcing them through rpcs that immediately fail and complete
1718 * the pages. recovery relies on this to empty the queued pages
1719 * before canceling the locks and evicting down the llite pages */
1720 if ((cli->cl_import == NULL || cli->cl_import->imp_invalid))
1723 if (cmd & OBD_BRW_WRITE) {
1724 if (atomic_read(&osc->oo_nr_writes) == 0)
1726 if (invalid_import) {
1727 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1730 if (!list_empty(&osc->oo_hp_exts)) {
1731 CDEBUG(D_CACHE, "high prio request forcing RPC\n");
1734 if (!list_empty(&osc->oo_urgent_exts)) {
1735 CDEBUG(D_CACHE, "urgent request forcing RPC\n");
1738 /* trigger a write rpc stream as long as there are dirtiers
1739 * waiting for space. as they're waiting, they're not going to
1740 * create more pages to coalesce with what's waiting.. */
1741 if (!list_empty(&cli->cl_cache_waiters)) {
1742 CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
1745 if (!list_empty(&osc->oo_full_exts)) {
1746 CDEBUG(D_CACHE, "full extent ready, make an RPC\n");
1750 if (atomic_read(&osc->oo_nr_reads) == 0)
1752 if (invalid_import) {
1753 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1756 /* all read are urgent. */
1757 if (!list_empty(&osc->oo_reading_exts))
1764 static void osc_update_pending(struct osc_object *obj, int cmd, int delta)
1766 struct client_obd *cli = osc_cli(obj);
1767 if (cmd & OBD_BRW_WRITE) {
1768 atomic_add(delta, &obj->oo_nr_writes);
1769 atomic_add(delta, &cli->cl_pending_w_pages);
1770 LASSERT(atomic_read(&obj->oo_nr_writes) >= 0);
1772 atomic_add(delta, &obj->oo_nr_reads);
1773 atomic_add(delta, &cli->cl_pending_r_pages);
1774 LASSERT(atomic_read(&obj->oo_nr_reads) >= 0);
1776 OSC_IO_DEBUG(obj, "update pending cmd %d delta %d.\n", cmd, delta);
1779 static int osc_makes_hprpc(struct osc_object *obj)
1781 return !list_empty(&obj->oo_hp_exts);
1784 static void on_list(struct list_head *item, struct list_head *list,
1787 if (list_empty(item) && should_be_on)
1788 list_add_tail(item, list);
1789 else if (!list_empty(item) && !should_be_on)
1790 list_del_init(item);
1793 /* maintain the osc's cli list membership invariants so that osc_send_oap_rpc
1794 * can find pages to build into rpcs quickly */
1795 static int __osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1797 if (osc_makes_hprpc(osc)) {
1799 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list, 0);
1800 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
1802 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
1803 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list,
1804 osc_makes_rpc(cli, osc, OBD_BRW_WRITE) ||
1805 osc_makes_rpc(cli, osc, OBD_BRW_READ));
1808 on_list(&osc->oo_write_item, &cli->cl_loi_write_list,
1809 atomic_read(&osc->oo_nr_writes) > 0);
1811 on_list(&osc->oo_read_item, &cli->cl_loi_read_list,
1812 atomic_read(&osc->oo_nr_reads) > 0);
1814 return osc_is_ready(osc);
1817 static int osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1821 spin_lock(&cli->cl_loi_list_lock);
1822 is_ready = __osc_list_maint(cli, osc);
1823 spin_unlock(&cli->cl_loi_list_lock);
1828 /* this is trying to propogate async writeback errors back up to the
1829 * application. As an async write fails we record the error code for later if
1830 * the app does an fsync. As long as errors persist we force future rpcs to be
1831 * sync so that the app can get a sync error and break the cycle of queueing
1832 * pages for which writeback will fail. */
1833 static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
1840 ar->ar_force_sync = 1;
1841 ar->ar_min_xid = ptlrpc_sample_next_xid();
1846 if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
1847 ar->ar_force_sync = 0;
1850 /* this must be called holding the loi list lock to give coverage to exit_cache,
1851 * async_flag maintenance, and oap_request */
1852 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
1853 struct osc_async_page *oap, int sent, int rc)
1855 struct osc_object *osc = oap->oap_obj;
1856 struct lov_oinfo *loi = osc->oo_oinfo;
1860 if (oap->oap_request != NULL) {
1861 xid = ptlrpc_req_xid(oap->oap_request);
1862 ptlrpc_req_finished(oap->oap_request);
1863 oap->oap_request = NULL;
1866 /* As the transfer for this page is being done, clear the flags */
1867 spin_lock(&oap->oap_lock);
1868 oap->oap_async_flags = 0;
1869 spin_unlock(&oap->oap_lock);
1870 oap->oap_interrupted = 0;
1872 if (oap->oap_cmd & OBD_BRW_WRITE && xid > 0) {
1873 spin_lock(&cli->cl_loi_list_lock);
1874 osc_process_ar(&cli->cl_ar, xid, rc);
1875 osc_process_ar(&loi->loi_ar, xid, rc);
1876 spin_unlock(&cli->cl_loi_list_lock);
1879 rc = osc_completion(env, oap, oap->oap_cmd, rc);
1881 CERROR("completion on oap %p obj %p returns %d.\n",
1887 struct extent_rpc_data {
1888 struct list_head *erd_rpc_list;
1889 unsigned int erd_page_count;
1890 unsigned int erd_max_pages;
1891 unsigned int erd_max_chunks;
1892 unsigned int erd_max_extents;
1895 static inline unsigned osc_extent_chunks(const struct osc_extent *ext)
1897 struct client_obd *cli = osc_cli(ext->oe_obj);
1898 unsigned ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
1900 return (ext->oe_end >> ppc_bits) - (ext->oe_start >> ppc_bits) + 1;
1904 * Try to add extent to one RPC. We need to think about the following things:
1905 * - # of pages must not be over max_pages_per_rpc
1906 * - extent must be compatible with previous ones
1908 static int try_to_add_extent_for_io(struct client_obd *cli,
1909 struct osc_extent *ext,
1910 struct extent_rpc_data *data)
1912 struct osc_extent *tmp;
1913 unsigned int chunk_count;
1914 struct osc_async_page *oap = list_first_entry(&ext->oe_pages,
1915 struct osc_async_page,
1919 EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE),
1921 OSC_EXTENT_DUMP(D_CACHE, ext, "trying to add this extent\n");
1923 if (data->erd_max_extents == 0)
1926 chunk_count = osc_extent_chunks(ext);
1927 EASSERTF(data->erd_page_count != 0 ||
1928 chunk_count <= data->erd_max_chunks, ext,
1929 "The first extent to be fit in a RPC contains %u chunks, "
1930 "which is over the limit %u.\n", chunk_count,
1931 data->erd_max_chunks);
1932 if (chunk_count > data->erd_max_chunks)
1935 data->erd_max_pages = max(ext->oe_mppr, data->erd_max_pages);
1936 EASSERTF(data->erd_page_count != 0 ||
1937 ext->oe_nr_pages <= data->erd_max_pages, ext,
1938 "The first extent to be fit in a RPC contains %u pages, "
1939 "which is over the limit %u.\n", ext->oe_nr_pages,
1940 data->erd_max_pages);
1941 if (data->erd_page_count + ext->oe_nr_pages > data->erd_max_pages)
1944 list_for_each_entry(tmp, data->erd_rpc_list, oe_link) {
1945 struct osc_async_page *oap2;
1946 oap2 = list_first_entry(&tmp->oe_pages, struct osc_async_page,
1948 EASSERT(tmp->oe_owner == current, tmp);
1950 if (overlapped(tmp, ext)) {
1951 OSC_EXTENT_DUMP(D_ERROR, tmp, "overlapped %p.\n", ext);
1955 if (oap2cl_page(oap)->cp_type != oap2cl_page(oap2)->cp_type) {
1956 CDEBUG(D_CACHE, "Do not permit different types of IO "
1961 if (tmp->oe_srvlock != ext->oe_srvlock ||
1962 !tmp->oe_grants != !ext->oe_grants ||
1963 tmp->oe_no_merge || ext->oe_no_merge)
1966 /* remove break for strict check */
1970 data->erd_max_extents--;
1971 data->erd_max_chunks -= chunk_count;
1972 data->erd_page_count += ext->oe_nr_pages;
1973 list_move_tail(&ext->oe_link, data->erd_rpc_list);
1974 ext->oe_owner = current;
1978 static inline unsigned osc_max_write_chunks(const struct client_obd *cli)
1983 * The maximum size of a single transaction is about 64MB in ZFS.
1984 * #define DMU_MAX_ACCESS (64 * 1024 * 1024)
1986 * Since ZFS is a copy-on-write file system, a single dirty page in
1987 * a chunk will result in the rewrite of the whole chunk, therefore
1988 * an RPC shouldn't be allowed to contain too many chunks otherwise
1989 * it will make transaction size much bigger than 64MB, especially
1990 * with big block size for ZFS.
1992 * This piece of code is to make sure that OSC won't send write RPCs
1993 * with too many chunks. The maximum chunk size that an RPC can cover
1994 * is set to PTLRPC_MAX_BRW_SIZE, which is defined to 16MB. Ideally
1995 * OST should tell the client what the biggest transaction size is,
1996 * but it's good enough for now.
1998 * This limitation doesn't apply to ldiskfs, which allows as many
1999 * chunks in one RPC as we want. However, it won't have any benefits
2000 * to have too many discontiguous pages in one RPC.
2002 * An osc_extent won't cover over a RPC size, so the chunks in an
2003 * osc_extent won't bigger than PTLRPC_MAX_BRW_SIZE >> chunkbits.
2005 return PTLRPC_MAX_BRW_SIZE >> cli->cl_chunkbits;
2009 * In order to prevent multiple ptlrpcd from breaking contiguous extents,
2010 * get_write_extent() takes all appropriate extents in atomic.
2012 * The following policy is used to collect extents for IO:
2013 * 1. Add as many HP extents as possible;
2014 * 2. Add the first urgent extent in urgent extent list and take it out of
2016 * 3. Add subsequent extents of this urgent extent;
2017 * 4. If urgent list is not empty, goto 2;
2018 * 5. Traverse the extent tree from the 1st extent;
2019 * 6. Above steps exit if there is no space in this RPC.
2021 static unsigned int get_write_extents(struct osc_object *obj,
2022 struct list_head *rpclist)
2024 struct client_obd *cli = osc_cli(obj);
2025 struct osc_extent *ext;
2026 struct extent_rpc_data data = {
2027 .erd_rpc_list = rpclist,
2028 .erd_page_count = 0,
2029 .erd_max_pages = cli->cl_max_pages_per_rpc,
2030 .erd_max_chunks = osc_max_write_chunks(cli),
2031 .erd_max_extents = 256,
2034 LASSERT(osc_object_is_locked(obj));
2035 while (!list_empty(&obj->oo_hp_exts)) {
2036 ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
2038 LASSERT(ext->oe_state == OES_CACHE);
2039 if (!try_to_add_extent_for_io(cli, ext, &data))
2040 return data.erd_page_count;
2041 EASSERT(ext->oe_nr_pages <= data.erd_max_pages, ext);
2043 if (data.erd_page_count == data.erd_max_pages)
2044 return data.erd_page_count;
2046 while (!list_empty(&obj->oo_urgent_exts)) {
2047 ext = list_entry(obj->oo_urgent_exts.next,
2048 struct osc_extent, oe_link);
2049 if (!try_to_add_extent_for_io(cli, ext, &data))
2050 return data.erd_page_count;
2052 if (data.erd_page_count == data.erd_max_pages)
2053 return data.erd_page_count;
2055 /* One key difference between full extents and other extents: full
2056 * extents can usually only be added if the rpclist was empty, so if we
2057 * can't add one, we continue on to trying to add normal extents. This
2058 * is so we don't miss adding extra extents to an RPC containing high
2059 * priority or urgent extents. */
2060 while (!list_empty(&obj->oo_full_exts)) {
2061 ext = list_entry(obj->oo_full_exts.next,
2062 struct osc_extent, oe_link);
2063 if (!try_to_add_extent_for_io(cli, ext, &data))
2066 if (data.erd_page_count == data.erd_max_pages)
2067 return data.erd_page_count;
2069 ext = first_extent(obj);
2070 while (ext != NULL) {
2071 if ((ext->oe_state != OES_CACHE) ||
2072 /* this extent may be already in current rpclist */
2073 (!list_empty(&ext->oe_link) && ext->oe_owner != NULL)) {
2074 ext = next_extent(ext);
2078 if (!try_to_add_extent_for_io(cli, ext, &data))
2079 return data.erd_page_count;
2081 ext = next_extent(ext);
2083 return data.erd_page_count;
2087 osc_send_write_rpc(const struct lu_env *env, struct client_obd *cli,
2088 struct osc_object *osc)
2091 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2092 struct osc_extent *ext;
2093 struct osc_extent *tmp;
2094 struct osc_extent *first = NULL;
2095 unsigned int page_count = 0;
2100 LASSERT(osc_object_is_locked(osc));
2102 page_count = get_write_extents(osc, &rpclist);
2103 LASSERT(equi(page_count == 0, list_empty(&rpclist)));
2105 if (list_empty(&rpclist))
2108 osc_update_pending(osc, OBD_BRW_WRITE, -page_count);
2110 list_for_each_entry(ext, &rpclist, oe_link) {
2111 LASSERT(ext->oe_state == OES_CACHE ||
2112 ext->oe_state == OES_LOCK_DONE);
2113 if (ext->oe_state == OES_CACHE)
2114 osc_extent_state_set(ext, OES_LOCKING);
2116 osc_extent_state_set(ext, OES_RPC);
2119 /* we're going to grab page lock, so release object lock because
2120 * lock order is page lock -> object lock. */
2121 osc_object_unlock(osc);
2123 list_for_each_entry_safe(ext, tmp, &rpclist, oe_link) {
2124 if (ext->oe_state == OES_LOCKING) {
2125 rc = osc_extent_make_ready(env, ext);
2126 if (unlikely(rc < 0)) {
2127 list_del_init(&ext->oe_link);
2128 osc_extent_finish(env, ext, 0, rc);
2132 if (first == NULL) {
2134 srvlock = ext->oe_srvlock;
2136 LASSERT(srvlock == ext->oe_srvlock);
2140 if (!list_empty(&rpclist)) {
2141 LASSERT(page_count > 0);
2142 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_WRITE);
2143 LASSERT(list_empty(&rpclist));
2146 osc_object_lock(osc);
2151 * prepare pages for ASYNC io and put pages in send queue.
2153 * \param cmd OBD_BRW_* macroses
2154 * \param lop pending pages
2156 * \return zero if no page added to send queue.
2157 * \return 1 if pages successfully added to send queue.
2158 * \return negative on errors.
2161 osc_send_read_rpc(const struct lu_env *env, struct client_obd *cli,
2162 struct osc_object *osc)
2165 struct osc_extent *ext;
2166 struct osc_extent *next;
2167 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2168 struct extent_rpc_data data = {
2169 .erd_rpc_list = &rpclist,
2170 .erd_page_count = 0,
2171 .erd_max_pages = cli->cl_max_pages_per_rpc,
2172 .erd_max_chunks = UINT_MAX,
2173 .erd_max_extents = UINT_MAX,
2178 LASSERT(osc_object_is_locked(osc));
2179 list_for_each_entry_safe(ext, next, &osc->oo_reading_exts, oe_link) {
2180 EASSERT(ext->oe_state == OES_LOCK_DONE, ext);
2181 if (!try_to_add_extent_for_io(cli, ext, &data))
2183 osc_extent_state_set(ext, OES_RPC);
2184 EASSERT(ext->oe_nr_pages <= data.erd_max_pages, ext);
2186 LASSERT(data.erd_page_count <= data.erd_max_pages);
2188 osc_update_pending(osc, OBD_BRW_READ, -data.erd_page_count);
2190 if (!list_empty(&rpclist)) {
2191 osc_object_unlock(osc);
2193 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_READ);
2194 LASSERT(list_empty(&rpclist));
2196 osc_object_lock(osc);
2201 #define list_to_obj(list, item) ({ \
2202 struct list_head *__tmp = (list)->next; \
2203 list_del_init(__tmp); \
2204 list_entry(__tmp, struct osc_object, oo_##item); \
2207 /* This is called by osc_check_rpcs() to find which objects have pages that
2208 * we could be sending. These lists are maintained by osc_makes_rpc(). */
2209 static struct osc_object *osc_next_obj(struct client_obd *cli)
2213 /* First return objects that have blocked locks so that they
2214 * will be flushed quickly and other clients can get the lock,
2215 * then objects which have pages ready to be stuffed into RPCs */
2216 if (!list_empty(&cli->cl_loi_hp_ready_list))
2217 RETURN(list_to_obj(&cli->cl_loi_hp_ready_list, hp_ready_item));
2218 if (!list_empty(&cli->cl_loi_ready_list))
2219 RETURN(list_to_obj(&cli->cl_loi_ready_list, ready_item));
2221 /* then if we have cache waiters, return all objects with queued
2222 * writes. This is especially important when many small files
2223 * have filled up the cache and not been fired into rpcs because
2224 * they don't pass the nr_pending/object threshhold */
2225 if (!list_empty(&cli->cl_cache_waiters) &&
2226 !list_empty(&cli->cl_loi_write_list))
2227 RETURN(list_to_obj(&cli->cl_loi_write_list, write_item));
2229 /* then return all queued objects when we have an invalid import
2230 * so that they get flushed */
2231 if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
2232 if (!list_empty(&cli->cl_loi_write_list))
2233 RETURN(list_to_obj(&cli->cl_loi_write_list,
2235 if (!list_empty(&cli->cl_loi_read_list))
2236 RETURN(list_to_obj(&cli->cl_loi_read_list,
2242 /* called with the loi list lock held */
2243 static void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli)
2244 __must_hold(&cli->cl_loi_list_lock)
2246 struct osc_object *osc;
2250 while ((osc = osc_next_obj(cli)) != NULL) {
2251 struct cl_object *obj = osc2cl(osc);
2252 struct lu_ref_link link;
2254 OSC_IO_DEBUG(osc, "%lu in flight\n", rpcs_in_flight(cli));
2256 if (osc_max_rpc_in_flight(cli, osc)) {
2257 __osc_list_maint(cli, osc);
2262 spin_unlock(&cli->cl_loi_list_lock);
2263 lu_object_ref_add_at(&obj->co_lu, &link, "check", current);
2265 /* attempt some read/write balancing by alternating between
2266 * reads and writes in an object. The makes_rpc checks here
2267 * would be redundant if we were getting read/write work items
2268 * instead of objects. we don't want send_oap_rpc to drain a
2269 * partial read pending queue when we're given this object to
2270 * do io on writes while there are cache waiters */
2271 osc_object_lock(osc);
2272 if (osc_makes_rpc(cli, osc, OBD_BRW_WRITE)) {
2273 rc = osc_send_write_rpc(env, cli, osc);
2275 CERROR("Write request failed with %d\n", rc);
2277 /* osc_send_write_rpc failed, mostly because of
2280 * It can't break here, because if:
2281 * - a page was submitted by osc_io_submit, so
2283 * - no request in flight
2284 * - no subsequent request
2285 * The system will be in live-lock state,
2286 * because there is no chance to call
2287 * osc_io_unplug() and osc_check_rpcs() any
2288 * more. pdflush can't help in this case,
2289 * because it might be blocked at grabbing
2290 * the page lock as we mentioned.
2292 * Anyway, continue to drain pages. */
2296 if (osc_makes_rpc(cli, osc, OBD_BRW_READ)) {
2297 rc = osc_send_read_rpc(env, cli, osc);
2299 CERROR("Read request failed with %d\n", rc);
2301 osc_object_unlock(osc);
2303 osc_list_maint(cli, osc);
2304 lu_object_ref_del_at(&obj->co_lu, &link, "check", current);
2305 cl_object_put(env, obj);
2307 spin_lock(&cli->cl_loi_list_lock);
2311 static int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
2312 struct osc_object *osc, int async)
2316 if (osc != NULL && osc_list_maint(cli, osc) == 0)
2320 spin_lock(&cli->cl_loi_list_lock);
2321 osc_check_rpcs(env, cli);
2322 spin_unlock(&cli->cl_loi_list_lock);
2324 CDEBUG(D_CACHE, "Queue writeback work for client %p.\n", cli);
2325 LASSERT(cli->cl_writeback_work != NULL);
2326 rc = ptlrpcd_queue_work(cli->cl_writeback_work);
2331 static int osc_io_unplug_async(const struct lu_env *env,
2332 struct client_obd *cli, struct osc_object *osc)
2334 return osc_io_unplug0(env, cli, osc, 1);
2337 void osc_io_unplug(const struct lu_env *env, struct client_obd *cli,
2338 struct osc_object *osc)
2340 (void)osc_io_unplug0(env, cli, osc, 0);
2343 int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
2344 struct page *page, loff_t offset)
2346 struct obd_export *exp = osc_export(osc);
2347 struct osc_async_page *oap = &ops->ops_oap;
2351 return cfs_size_round(sizeof(*oap));
2353 oap->oap_magic = OAP_MAGIC;
2354 oap->oap_cli = &exp->exp_obd->u.cli;
2357 oap->oap_page = page;
2358 oap->oap_obj_off = offset;
2359 LASSERT(!(offset & ~PAGE_MASK));
2361 if (cfs_capable(CFS_CAP_SYS_RESOURCE))
2362 oap->oap_brw_flags = OBD_BRW_NOQUOTA;
2364 INIT_LIST_HEAD(&oap->oap_pending_item);
2365 INIT_LIST_HEAD(&oap->oap_rpc_item);
2367 spin_lock_init(&oap->oap_lock);
2368 CDEBUG(D_INFO, "oap %p page %p obj off %llu\n",
2369 oap, page, oap->oap_obj_off);
2373 int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
2374 struct osc_page *ops)
2376 struct osc_io *oio = osc_env_io(env);
2377 struct osc_extent *ext = NULL;
2378 struct osc_async_page *oap = &ops->ops_oap;
2379 struct client_obd *cli = oap->oap_cli;
2380 struct osc_object *osc = oap->oap_obj;
2383 unsigned int grants = 0;
2384 u32 brw_flags = OBD_BRW_ASYNC;
2385 int cmd = OBD_BRW_WRITE;
2386 int need_release = 0;
2390 if (oap->oap_magic != OAP_MAGIC)
2393 if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
2396 if (!list_empty(&oap->oap_pending_item) ||
2397 !list_empty(&oap->oap_rpc_item))
2400 /* Set the OBD_BRW_SRVLOCK before the page is queued. */
2401 brw_flags |= ops->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
2402 if (cfs_capable(CFS_CAP_SYS_RESOURCE)) {
2403 brw_flags |= OBD_BRW_NOQUOTA;
2404 cmd |= OBD_BRW_NOQUOTA;
2407 /* check if the file's owner/group is over quota */
2408 if (!(cmd & OBD_BRW_NOQUOTA)) {
2409 struct cl_object *obj;
2410 struct cl_attr *attr;
2411 unsigned int qid[LL_MAXQUOTAS];
2413 obj = cl_object_top(&osc->oo_cl);
2414 attr = &osc_env_info(env)->oti_attr;
2416 cl_object_attr_lock(obj);
2417 rc = cl_object_attr_get(env, obj, attr);
2418 cl_object_attr_unlock(obj);
2420 qid[USRQUOTA] = attr->cat_uid;
2421 qid[GRPQUOTA] = attr->cat_gid;
2422 if (rc == 0 && osc_quota_chkdq(cli, qid) == NO_QUOTA)
2429 oap->oap_page_off = ops->ops_from;
2430 oap->oap_count = ops->ops_to - ops->ops_from;
2431 /* No need to hold a lock here,
2432 * since this page is not in any list yet. */
2433 oap->oap_async_flags = 0;
2434 oap->oap_brw_flags = brw_flags;
2436 OSC_IO_DEBUG(osc, "oap %p page %p added for cmd %d\n",
2437 oap, oap->oap_page, oap->oap_cmd & OBD_BRW_RWMASK);
2439 index = osc_index(oap2osc(oap));
2441 /* Add this page into extent by the following steps:
2442 * 1. if there exists an active extent for this IO, mostly this page
2443 * can be added to the active extent and sometimes we need to
2444 * expand extent to accomodate this page;
2445 * 2. otherwise, a new extent will be allocated. */
2447 ext = oio->oi_active;
2448 if (ext != NULL && ext->oe_start <= index && ext->oe_max_end >= index) {
2449 /* one chunk plus extent overhead must be enough to write this
2451 grants = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
2452 if (ext->oe_end >= index)
2455 /* it doesn't need any grant to dirty this page */
2456 spin_lock(&cli->cl_loi_list_lock);
2457 rc = osc_enter_cache_try(cli, oap, grants, 0);
2458 spin_unlock(&cli->cl_loi_list_lock);
2459 if (rc == 0) { /* try failed */
2462 } else if (ext->oe_end < index) {
2464 /* try to expand this extent */
2465 rc = osc_extent_expand(ext, index, &tmp);
2468 /* don't free reserved grant */
2470 OSC_EXTENT_DUMP(D_CACHE, ext,
2471 "expanded for %lu.\n", index);
2472 osc_unreserve_grant(cli, grants, tmp);
2477 } else if (ext != NULL) {
2478 /* index is located outside of active extent */
2482 osc_extent_release(env, ext);
2483 oio->oi_active = NULL;
2488 tmp = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
2490 /* try to find new extent to cover this page */
2491 LASSERT(oio->oi_active == NULL);
2492 /* we may have allocated grant for this page if we failed
2493 * to expand the previous active extent. */
2494 LASSERT(ergo(grants > 0, grants >= tmp));
2498 /* we haven't allocated grant for this page. */
2499 rc = osc_enter_cache(env, cli, oap, tmp);
2506 ext = osc_extent_find(env, osc, index, &tmp);
2508 LASSERT(tmp == grants);
2509 osc_exit_cache(cli, oap);
2513 oio->oi_active = ext;
2517 osc_unreserve_grant(cli, grants, tmp);
2520 LASSERT(ergo(rc == 0, ext != NULL));
2522 EASSERTF(ext->oe_end >= index && ext->oe_start <= index,
2523 ext, "index = %lu.\n", index);
2524 LASSERT((oap->oap_brw_flags & OBD_BRW_FROM_GRANT) != 0);
2526 osc_object_lock(osc);
2527 if (ext->oe_nr_pages == 0)
2528 ext->oe_srvlock = ops->ops_srvlock;
2530 LASSERT(ext->oe_srvlock == ops->ops_srvlock);
2532 list_add_tail(&oap->oap_pending_item, &ext->oe_pages);
2533 osc_object_unlock(osc);
2538 int osc_teardown_async_page(const struct lu_env *env,
2539 struct osc_object *obj, struct osc_page *ops)
2541 struct osc_async_page *oap = &ops->ops_oap;
2545 LASSERT(oap->oap_magic == OAP_MAGIC);
2547 CDEBUG(D_INFO, "teardown oap %p page %p at index %lu.\n",
2548 oap, ops, osc_index(oap2osc(oap)));
2550 if (!list_empty(&oap->oap_rpc_item)) {
2551 CDEBUG(D_CACHE, "oap %p is not in cache.\n", oap);
2553 } else if (!list_empty(&oap->oap_pending_item)) {
2554 struct osc_extent *ext = NULL;
2556 osc_object_lock(obj);
2557 ext = osc_extent_lookup(obj, osc_index(oap2osc(oap)));
2558 osc_object_unlock(obj);
2559 /* only truncated pages are allowed to be taken out.
2560 * See osc_extent_truncate() and osc_cache_truncate_start()
2562 if (ext != NULL && ext->oe_state != OES_TRUNC) {
2563 OSC_EXTENT_DUMP(D_ERROR, ext, "trunc at %lu.\n",
2564 osc_index(oap2osc(oap)));
2568 osc_extent_put(env, ext);
2574 * This is called when a page is picked up by kernel to write out.
2576 * We should find out the corresponding extent and add the whole extent
2577 * into urgent list. The extent may be being truncated or used, handle it
2580 int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
2581 struct osc_page *ops)
2583 struct osc_extent *ext = NULL;
2584 struct osc_object *obj = cl2osc(ops->ops_cl.cpl_obj);
2585 struct cl_page *cp = ops->ops_cl.cpl_page;
2586 pgoff_t index = osc_index(ops);
2587 struct osc_async_page *oap = &ops->ops_oap;
2588 bool unplug = false;
2592 osc_object_lock(obj);
2593 ext = osc_extent_lookup(obj, index);
2595 osc_extent_tree_dump(D_ERROR, obj);
2596 LASSERTF(0, "page index %lu is NOT covered.\n", index);
2599 switch (ext->oe_state) {
2602 CL_PAGE_DEBUG(D_ERROR, env, cp, "flush an in-rpc page?\n");
2606 /* If we know this extent is being written out, we should abort
2607 * so that the writer can make this page ready. Otherwise, there
2608 * exists a deadlock problem because other process can wait for
2609 * page writeback bit holding page lock; and meanwhile in
2610 * vvp_page_make_ready(), we need to grab page lock before
2611 * really sending the RPC. */
2613 /* race with truncate, page will be redirtied */
2615 /* The extent is active so we need to abort and let the caller
2616 * re-dirty the page. If we continued on here, and we were the
2617 * one making the extent active, we could deadlock waiting for
2618 * the page writeback to clear but it won't because the extent
2619 * is active and won't be written out. */
2620 GOTO(out, rc = -EAGAIN);
2625 rc = cl_page_prep(env, io, cp, CRT_WRITE);
2629 spin_lock(&oap->oap_lock);
2630 oap->oap_async_flags |= ASYNC_READY|ASYNC_URGENT;
2631 spin_unlock(&oap->oap_lock);
2633 if (memory_pressure_get())
2634 ext->oe_memalloc = 1;
2637 if (ext->oe_state == OES_CACHE) {
2638 OSC_EXTENT_DUMP(D_CACHE, ext,
2639 "flush page %p make it urgent.\n", oap);
2640 if (list_empty(&ext->oe_link))
2641 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2648 osc_object_unlock(obj);
2649 osc_extent_put(env, ext);
2651 osc_io_unplug_async(env, osc_cli(obj), obj);
2656 * this is called when a sync waiter receives an interruption. Its job is to
2657 * get the caller woken as soon as possible. If its page hasn't been put in an
2658 * rpc yet it can dequeue immediately. Otherwise it has to mark the rpc as
2659 * desiring interruption which will forcefully complete the rpc once the rpc
2662 int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops)
2664 struct osc_async_page *oap = &ops->ops_oap;
2665 struct osc_object *obj = oap->oap_obj;
2666 struct client_obd *cli = osc_cli(obj);
2667 struct osc_extent *ext;
2668 struct osc_extent *found = NULL;
2669 struct list_head *plist;
2670 pgoff_t index = osc_index(ops);
2675 LASSERT(!oap->oap_interrupted);
2676 oap->oap_interrupted = 1;
2678 /* Find out the caching extent */
2679 osc_object_lock(obj);
2680 if (oap->oap_cmd & OBD_BRW_WRITE) {
2681 plist = &obj->oo_urgent_exts;
2682 cmd = OBD_BRW_WRITE;
2684 plist = &obj->oo_reading_exts;
2687 list_for_each_entry(ext, plist, oe_link) {
2688 if (ext->oe_start <= index && ext->oe_end >= index) {
2689 LASSERT(ext->oe_state == OES_LOCK_DONE);
2690 /* For OES_LOCK_DONE state extent, it has already held
2691 * a refcount for RPC. */
2692 found = osc_extent_get(ext);
2696 if (found != NULL) {
2697 list_del_init(&found->oe_link);
2698 osc_update_pending(obj, cmd, -found->oe_nr_pages);
2699 osc_object_unlock(obj);
2701 osc_extent_finish(env, found, 0, -EINTR);
2702 osc_extent_put(env, found);
2705 osc_object_unlock(obj);
2706 /* ok, it's been put in an rpc. only one oap gets a request
2708 if (oap->oap_request != NULL) {
2709 ptlrpc_mark_interrupted(oap->oap_request);
2710 ptlrpcd_wake(oap->oap_request);
2711 ptlrpc_req_finished(oap->oap_request);
2712 oap->oap_request = NULL;
2716 osc_list_maint(cli, obj);
2720 int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
2721 struct list_head *list, int cmd, int brw_flags)
2723 struct client_obd *cli = osc_cli(obj);
2724 struct osc_extent *ext;
2725 struct osc_async_page *oap;
2727 int mppr = cli->cl_max_pages_per_rpc;
2728 bool can_merge = true;
2729 pgoff_t start = CL_PAGE_EOF;
2733 list_for_each_entry(oap, list, oap_pending_item) {
2734 struct osc_page *opg = oap2osc_page(oap);
2735 pgoff_t index = osc_index(opg);
2742 mppr <<= (page_count > mppr);
2744 if (unlikely(opg->ops_from > 0 || opg->ops_to < PAGE_SIZE))
2748 ext = osc_extent_alloc(obj);
2750 struct osc_async_page *tmp;
2752 list_for_each_entry_safe(oap, tmp, list, oap_pending_item) {
2753 list_del_init(&oap->oap_pending_item);
2754 osc_ap_completion(env, cli, oap, 0, -ENOMEM);
2759 ext->oe_rw = !!(cmd & OBD_BRW_READ);
2761 ext->oe_no_merge = !can_merge;
2763 ext->oe_start = start;
2764 ext->oe_end = ext->oe_max_end = end;
2766 ext->oe_srvlock = !!(brw_flags & OBD_BRW_SRVLOCK);
2767 ext->oe_nr_pages = page_count;
2768 ext->oe_mppr = mppr;
2769 list_splice_init(list, &ext->oe_pages);
2771 osc_object_lock(obj);
2772 /* Reuse the initial refcount for RPC, don't drop it */
2773 osc_extent_state_set(ext, OES_LOCK_DONE);
2774 if (cmd & OBD_BRW_WRITE) {
2775 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2776 osc_update_pending(obj, OBD_BRW_WRITE, page_count);
2778 list_add_tail(&ext->oe_link, &obj->oo_reading_exts);
2779 osc_update_pending(obj, OBD_BRW_READ, page_count);
2781 osc_object_unlock(obj);
2783 osc_io_unplug_async(env, cli, obj);
2788 * Called by osc_io_setattr_start() to freeze and destroy covering extents.
2790 int osc_cache_truncate_start(const struct lu_env *env, struct osc_object *obj,
2791 __u64 size, struct osc_extent **extp)
2793 struct client_obd *cli = osc_cli(obj);
2794 struct osc_extent *ext;
2795 struct osc_extent *waiting = NULL;
2797 struct list_head list = LIST_HEAD_INIT(list);
2802 /* pages with index greater or equal to index will be truncated. */
2803 index = cl_index(osc2cl(obj), size);
2804 partial = size > cl_offset(osc2cl(obj), index);
2807 osc_object_lock(obj);
2808 ext = osc_extent_search(obj, index);
2810 ext = first_extent(obj);
2811 else if (ext->oe_end < index)
2812 ext = next_extent(ext);
2813 while (ext != NULL) {
2814 EASSERT(ext->oe_state != OES_TRUNC, ext);
2816 if (ext->oe_state > OES_CACHE || ext->oe_urgent) {
2817 /* if ext is in urgent state, it means there must exist
2818 * a page already having been flushed by write_page().
2819 * We have to wait for this extent because we can't
2820 * truncate that page. */
2821 OSC_EXTENT_DUMP(D_CACHE, ext,
2822 "waiting for busy extent\n");
2823 waiting = osc_extent_get(ext);
2827 OSC_EXTENT_DUMP(D_CACHE, ext, "try to trunc:%llu.\n", size);
2829 osc_extent_get(ext);
2830 if (ext->oe_state == OES_ACTIVE) {
2831 /* though we grab inode mutex for write path, but we
2832 * release it before releasing extent(in osc_io_end()),
2833 * so there is a race window that an extent is still
2834 * in OES_ACTIVE when truncate starts. */
2835 LASSERT(!ext->oe_trunc_pending);
2836 ext->oe_trunc_pending = 1;
2838 EASSERT(ext->oe_state == OES_CACHE, ext);
2839 osc_extent_state_set(ext, OES_TRUNC);
2840 osc_update_pending(obj, OBD_BRW_WRITE,
2843 /* This extent could be on the full extents list, that's OK */
2844 EASSERT(!ext->oe_hp && !ext->oe_urgent, ext);
2845 if (!list_empty(&ext->oe_link))
2846 list_move_tail(&ext->oe_link, &list);
2848 list_add_tail(&ext->oe_link, &list);
2850 ext = next_extent(ext);
2852 osc_object_unlock(obj);
2854 osc_list_maint(cli, obj);
2856 while (!list_empty(&list)) {
2859 ext = list_entry(list.next, struct osc_extent, oe_link);
2860 list_del_init(&ext->oe_link);
2862 /* extent may be in OES_ACTIVE state because inode mutex
2863 * is released before osc_io_end() in file write case */
2864 if (ext->oe_state != OES_TRUNC)
2865 osc_extent_wait(env, ext, OES_TRUNC);
2867 rc = osc_extent_truncate(ext, index, partial);
2872 OSC_EXTENT_DUMP(D_ERROR, ext,
2873 "truncate error %d\n", rc);
2874 } else if (ext->oe_nr_pages == 0) {
2875 osc_extent_remove(ext);
2877 /* this must be an overlapped extent which means only
2878 * part of pages in this extent have been truncated.
2880 EASSERTF(ext->oe_start <= index, ext,
2881 "trunc index = %lu/%d.\n", index, partial);
2882 /* fix index to skip this partially truncated extent */
2883 index = ext->oe_end + 1;
2886 /* we need to hold this extent in OES_TRUNC state so
2887 * that no writeback will happen. This is to avoid
2889 * Only partial truncate can reach here, if @size is
2890 * not zero, the caller should provide a valid @extp. */
2891 LASSERT(*extp == NULL);
2892 *extp = osc_extent_get(ext);
2893 OSC_EXTENT_DUMP(D_CACHE, ext,
2894 "trunc at %llu\n", size);
2896 osc_extent_put(env, ext);
2898 if (waiting != NULL) {
2901 /* ignore the result of osc_extent_wait the write initiator
2902 * should take care of it. */
2903 rc = osc_extent_wait(env, waiting, OES_INV);
2905 OSC_EXTENT_DUMP(D_CACHE, waiting, "error: %d.\n", rc);
2907 osc_extent_put(env, waiting);
2915 * Called after osc_io_setattr_end to add oio->oi_trunc back to cache.
2917 void osc_cache_truncate_end(const struct lu_env *env, struct osc_extent *ext)
2920 struct osc_object *obj = ext->oe_obj;
2921 bool unplug = false;
2923 EASSERT(ext->oe_nr_pages > 0, ext);
2924 EASSERT(ext->oe_state == OES_TRUNC, ext);
2925 EASSERT(!ext->oe_urgent, ext);
2927 OSC_EXTENT_DUMP(D_CACHE, ext, "trunc -> cache.\n");
2928 osc_object_lock(obj);
2929 osc_extent_state_set(ext, OES_CACHE);
2930 if (ext->oe_fsync_wait && !ext->oe_urgent) {
2932 list_move_tail(&ext->oe_link, &obj->oo_urgent_exts);
2935 osc_update_pending(obj, OBD_BRW_WRITE, ext->oe_nr_pages);
2936 osc_object_unlock(obj);
2937 osc_extent_put(env, ext);
2940 osc_io_unplug_async(env, osc_cli(obj), obj);
2945 * Wait for extents in a specific range to be written out.
2946 * The caller must have called osc_cache_writeback_range() to issue IO
2947 * otherwise it will take a long time for this function to finish.
2949 * Caller must hold inode_mutex , or cancel exclusive dlm lock so that
2950 * nobody else can dirty this range of file while we're waiting for
2951 * extents to be written.
2953 int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
2954 pgoff_t start, pgoff_t end)
2956 struct osc_extent *ext;
2957 pgoff_t index = start;
2962 osc_object_lock(obj);
2963 ext = osc_extent_search(obj, index);
2965 ext = first_extent(obj);
2966 else if (ext->oe_end < index)
2967 ext = next_extent(ext);
2968 while (ext != NULL) {
2971 if (ext->oe_start > end)
2974 if (!ext->oe_fsync_wait) {
2975 ext = next_extent(ext);
2979 EASSERT(ergo(ext->oe_state == OES_CACHE,
2980 ext->oe_hp || ext->oe_urgent), ext);
2981 EASSERT(ergo(ext->oe_state == OES_ACTIVE,
2982 !ext->oe_hp && ext->oe_urgent), ext);
2984 index = ext->oe_end + 1;
2985 osc_extent_get(ext);
2986 osc_object_unlock(obj);
2988 rc = osc_extent_wait(env, ext, OES_INV);
2991 osc_extent_put(env, ext);
2994 osc_object_unlock(obj);
2996 OSC_IO_DEBUG(obj, "sync file range.\n");
3001 * Called to write out a range of osc object.
3003 * @hp : should be set this is caused by lock cancel;
3004 * @discard: is set if dirty pages should be dropped - file will be deleted or
3005 * truncated, this implies there is no partially discarding extents.
3007 * Return how many pages will be issued, or error code if error occurred.
3009 int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
3010 pgoff_t start, pgoff_t end, int hp, int discard)
3012 struct osc_extent *ext;
3013 struct list_head discard_list = LIST_HEAD_INIT(discard_list);
3014 bool unplug = false;
3018 osc_object_lock(obj);
3019 ext = osc_extent_search(obj, start);
3021 ext = first_extent(obj);
3022 else if (ext->oe_end < start)
3023 ext = next_extent(ext);
3024 while (ext != NULL) {
3025 if (ext->oe_start > end)
3028 ext->oe_fsync_wait = 1;
3029 switch (ext->oe_state) {
3031 result += ext->oe_nr_pages;
3033 struct list_head *list = NULL;
3035 EASSERT(!ext->oe_hp, ext);
3037 list = &obj->oo_hp_exts;
3038 } else if (!ext->oe_urgent) {
3040 list = &obj->oo_urgent_exts;
3043 list_move_tail(&ext->oe_link, list);
3046 /* the only discarder is lock cancelling, so
3047 * [start, end] must contain this extent */
3048 EASSERT(ext->oe_start >= start &&
3049 ext->oe_max_end <= end, ext);
3050 osc_extent_state_set(ext, OES_LOCKING);
3051 ext->oe_owner = current;
3052 list_move_tail(&ext->oe_link,
3054 osc_update_pending(obj, OBD_BRW_WRITE,
3059 /* It's pretty bad to wait for ACTIVE extents, because
3060 * we don't know how long we will wait for it to be
3061 * flushed since it may be blocked at awaiting more
3062 * grants. We do this for the correctness of fsync. */
3063 LASSERT(hp == 0 && discard == 0);
3067 /* this extent is being truncated, can't do anything
3068 * for it now. it will be set to urgent after truncate
3069 * is finished in osc_cache_truncate_end(). */
3073 ext = next_extent(ext);
3075 osc_object_unlock(obj);
3077 LASSERT(ergo(!discard, list_empty(&discard_list)));
3078 if (!list_empty(&discard_list)) {
3079 struct osc_extent *tmp;
3082 osc_list_maint(osc_cli(obj), obj);
3083 list_for_each_entry_safe(ext, tmp, &discard_list, oe_link) {
3084 list_del_init(&ext->oe_link);
3085 EASSERT(ext->oe_state == OES_LOCKING, ext);
3087 /* Discard caching pages. We don't actually write this
3088 * extent out but we complete it as if we did. */
3089 rc = osc_extent_make_ready(env, ext);
3090 if (unlikely(rc < 0)) {
3091 OSC_EXTENT_DUMP(D_ERROR, ext,
3092 "make_ready returned %d\n", rc);
3097 /* finish the extent as if the pages were sent */
3098 osc_extent_finish(env, ext, 0, 0);
3103 osc_io_unplug(env, osc_cli(obj), obj);
3105 if (hp || discard) {
3107 rc = osc_cache_wait_range(env, obj, start, end);
3108 if (result >= 0 && rc < 0)
3112 OSC_IO_DEBUG(obj, "pageout [%lu, %lu], %d.\n", start, end, result);
3117 * Returns a list of pages by a given [start, end] of \a obj.
3119 * \param resched If not NULL, then we give up before hogging CPU for too
3120 * long and set *resched = 1, in that case caller should implement a retry
3123 * Gang tree lookup (radix_tree_gang_lookup()) optimization is absolutely
3124 * crucial in the face of [offset, EOF] locks.
3126 * Return at least one page in @queue unless there is no covered page.
3128 int osc_page_gang_lookup(const struct lu_env *env, struct cl_io *io,
3129 struct osc_object *osc, pgoff_t start, pgoff_t end,
3130 osc_page_gang_cbt cb, void *cbdata)
3132 struct osc_page *ops;
3138 int res = CLP_GANG_OKAY;
3139 bool tree_lock = true;
3143 pvec = osc_env_info(env)->oti_pvec;
3144 spin_lock(&osc->oo_tree_lock);
3145 while ((nr = radix_tree_gang_lookup(&osc->oo_tree, pvec,
3146 idx, OTI_PVEC_SIZE)) > 0) {
3147 struct cl_page *page;
3148 bool end_of_region = false;
3150 for (i = 0, j = 0; i < nr; ++i) {
3154 idx = osc_index(ops);
3156 end_of_region = true;
3160 page = ops->ops_cl.cpl_page;
3161 LASSERT(page->cp_type == CPT_CACHEABLE);
3162 if (page->cp_state == CPS_FREEING)
3166 lu_ref_add_atomic(&page->cp_reference,
3167 "gang_lookup", current);
3173 * Here a delicate locking dance is performed. Current thread
3174 * holds a reference to a page, but has to own it before it
3175 * can be placed into queue. Owning implies waiting, so
3176 * radix-tree lock is to be released. After a wait one has to
3177 * check that pages weren't truncated (cl_page_own() returns
3178 * error in the latter case).
3180 spin_unlock(&osc->oo_tree_lock);
3183 for (i = 0; i < j; ++i) {
3185 if (res == CLP_GANG_OKAY)
3186 res = (*cb)(env, io, ops, cbdata);
3188 page = ops->ops_cl.cpl_page;
3189 lu_ref_del(&page->cp_reference, "gang_lookup", current);
3190 cl_page_put(env, page);
3192 if (nr < OTI_PVEC_SIZE || end_of_region)
3195 if (res == CLP_GANG_OKAY && need_resched())
3196 res = CLP_GANG_RESCHED;
3197 if (res != CLP_GANG_OKAY)
3200 spin_lock(&osc->oo_tree_lock);
3204 spin_unlock(&osc->oo_tree_lock);
3209 * Check if page @page is covered by an extra lock or discard it.
3211 static int check_and_discard_cb(const struct lu_env *env, struct cl_io *io,
3212 struct osc_page *ops, void *cbdata)
3214 struct osc_thread_info *info = osc_env_info(env);
3215 struct osc_object *osc = cbdata;
3218 index = osc_index(ops);
3219 if (index >= info->oti_fn_index) {
3220 struct ldlm_lock *tmp;
3221 struct cl_page *page = ops->ops_cl.cpl_page;
3223 /* refresh non-overlapped index */
3224 tmp = osc_dlmlock_at_pgoff(env, osc, index,
3225 OSC_DAP_FL_TEST_LOCK);
3227 __u64 end = tmp->l_policy_data.l_extent.end;
3228 /* Cache the first-non-overlapped index so as to skip
3229 * all pages within [index, oti_fn_index). This is safe
3230 * because if tmp lock is canceled, it will discard
3232 info->oti_fn_index = cl_index(osc2cl(osc), end + 1);
3233 if (end == OBD_OBJECT_EOF)
3234 info->oti_fn_index = CL_PAGE_EOF;
3236 } else if (cl_page_own(env, io, page) == 0) {
3237 /* discard the page */
3238 cl_page_discard(env, io, page);
3239 cl_page_disown(env, io, page);
3241 LASSERT(page->cp_state == CPS_FREEING);
3245 info->oti_next_index = index + 1;
3246 return CLP_GANG_OKAY;
3249 static int discard_cb(const struct lu_env *env, struct cl_io *io,
3250 struct osc_page *ops, void *cbdata)
3252 struct osc_thread_info *info = osc_env_info(env);
3253 struct cl_page *page = ops->ops_cl.cpl_page;
3255 /* page is top page. */
3256 info->oti_next_index = osc_index(ops) + 1;
3257 if (cl_page_own(env, io, page) == 0) {
3258 if (!ergo(page->cp_type == CPT_CACHEABLE,
3259 !PageDirty(cl_page_vmpage(page))))
3260 CL_PAGE_DEBUG(D_ERROR, env, page,
3261 "discard dirty page?\n");
3263 /* discard the page */
3264 cl_page_discard(env, io, page);
3265 cl_page_disown(env, io, page);
3267 LASSERT(page->cp_state == CPS_FREEING);
3270 return CLP_GANG_OKAY;
3274 * Discard pages protected by the given lock. This function traverses radix
3275 * tree to find all covering pages and discard them. If a page is being covered
3276 * by other locks, it should remain in cache.
3278 * If error happens on any step, the process continues anyway (the reasoning
3279 * behind this being that lock cancellation cannot be delayed indefinitely).
3281 int osc_lock_discard_pages(const struct lu_env *env, struct osc_object *osc,
3282 pgoff_t start, pgoff_t end, enum cl_lock_mode mode)
3284 struct osc_thread_info *info = osc_env_info(env);
3285 struct cl_io *io = &info->oti_io;
3286 osc_page_gang_cbt cb;
3292 io->ci_obj = cl_object_top(osc2cl(osc));
3293 io->ci_ignore_layout = 1;
3294 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
3298 cb = mode == CLM_READ ? check_and_discard_cb : discard_cb;
3299 info->oti_fn_index = info->oti_next_index = start;
3301 res = osc_page_gang_lookup(env, io, osc,
3302 info->oti_next_index, end, cb, osc);
3303 if (info->oti_next_index > end)
3306 if (res == CLP_GANG_RESCHED)
3308 } while (res != CLP_GANG_OKAY);
3310 cl_io_fini(env, io);