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, 2013, 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,
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';
87 if (ext->oe_trunc_pending)
89 if (ext->oe_fsync_wait)
95 static inline char list_empty_marker(struct list_head *list)
97 return list_empty(list) ? '-' : '+';
100 #define EXTSTR "[%lu -> %lu/%lu]"
101 #define EXTPARA(ext) (ext)->oe_start, (ext)->oe_end, (ext)->oe_max_end
102 static const char *oes_strings[] = {
103 "inv", "active", "cache", "locking", "lockdone", "rpc", "trunc", NULL };
105 #define OSC_EXTENT_DUMP(lvl, extent, fmt, ...) do { \
106 struct osc_extent *__ext = (extent); \
110 "extent %p@{" EXTSTR ", " \
111 "[%d|%d|%c|%s|%s|%p], [%d|%d|%c|%c|%p|%u|%p]} " fmt, \
112 /* ----- extent part 0 ----- */ \
113 __ext, EXTPARA(__ext), \
114 /* ----- part 1 ----- */ \
115 atomic_read(&__ext->oe_refc), \
116 atomic_read(&__ext->oe_users), \
117 list_empty_marker(&__ext->oe_link), \
118 oes_strings[__ext->oe_state], ext_flags(__ext, __buf), \
120 /* ----- part 2 ----- */ \
121 __ext->oe_grants, __ext->oe_nr_pages, \
122 list_empty_marker(&__ext->oe_pages), \
123 waitqueue_active(&__ext->oe_waitq) ? '+' : '-', \
124 __ext->oe_osclock, __ext->oe_mppr, __ext->oe_owner, \
125 /* ----- part 4 ----- */ \
130 #define EASSERTF(expr, ext, fmt, args...) do { \
132 OSC_EXTENT_DUMP(D_ERROR, (ext), fmt, ##args); \
133 osc_extent_tree_dump(D_ERROR, (ext)->oe_obj); \
139 #define EASSERT(expr, ext) EASSERTF(expr, ext, "\n")
141 static inline struct osc_extent *rb_extent(struct rb_node *n)
146 return container_of(n, struct osc_extent, oe_node);
149 static inline struct osc_extent *next_extent(struct osc_extent *ext)
154 LASSERT(ext->oe_intree);
155 return rb_extent(rb_next(&ext->oe_node));
158 static inline struct osc_extent *prev_extent(struct osc_extent *ext)
163 LASSERT(ext->oe_intree);
164 return rb_extent(rb_prev(&ext->oe_node));
167 static inline struct osc_extent *first_extent(struct osc_object *obj)
169 return rb_extent(rb_first(&obj->oo_root));
172 /* object must be locked by caller. */
173 static int osc_extent_sanity_check0(struct osc_extent *ext,
174 const char *func, const int line)
176 struct osc_object *obj = ext->oe_obj;
177 struct osc_async_page *oap;
181 if (!osc_object_is_locked(obj))
184 if (ext->oe_state >= OES_STATE_MAX)
187 if (atomic_read(&ext->oe_refc) <= 0)
190 if (atomic_read(&ext->oe_refc) < atomic_read(&ext->oe_users))
193 switch (ext->oe_state) {
195 if (ext->oe_nr_pages > 0 || !list_empty(&ext->oe_pages))
200 if (atomic_read(&ext->oe_users) == 0)
204 if (ext->oe_fsync_wait && !ext->oe_urgent)
208 if (ext->oe_grants == 0)
210 if (ext->oe_fsync_wait && !ext->oe_urgent && !ext->oe_hp)
213 if (atomic_read(&ext->oe_users) > 0)
217 if (ext->oe_max_end < ext->oe_end || ext->oe_end < ext->oe_start)
220 if (ext->oe_osclock == NULL && ext->oe_grants > 0)
223 if (ext->oe_osclock) {
224 struct cl_lock_descr *descr;
225 descr = &ext->oe_osclock->cll_descr;
226 if (!(descr->cld_start <= ext->oe_start &&
227 descr->cld_end >= ext->oe_max_end))
231 if (ext->oe_nr_pages > ext->oe_mppr)
234 /* Do not verify page list if extent is in RPC. This is because an
235 * in-RPC extent is supposed to be exclusively accessible w/o lock. */
236 if (ext->oe_state > OES_CACHE)
243 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
244 pgoff_t index = osc_index(oap2osc(oap));
246 if (index > ext->oe_end || index < ext->oe_start)
249 if (page_count != ext->oe_nr_pages)
254 OSC_EXTENT_DUMP(D_ERROR, ext,
255 "%s:%d sanity check %p failed with rc = %d\n",
256 func, line, ext, rc);
260 #define sanity_check_nolock(ext) \
261 osc_extent_sanity_check0(ext, __func__, __LINE__)
263 #define sanity_check(ext) ({ \
265 osc_object_lock((ext)->oe_obj); \
266 __res = sanity_check_nolock(ext); \
267 osc_object_unlock((ext)->oe_obj); \
273 * sanity check - to make sure there is no overlapped extent in the tree.
275 static int osc_extent_is_overlapped(struct osc_object *obj,
276 struct osc_extent *ext)
278 struct osc_extent *tmp;
280 LASSERT(osc_object_is_locked(obj));
285 for (tmp = first_extent(obj); tmp != NULL; tmp = next_extent(tmp)) {
288 if (tmp->oe_end >= ext->oe_start &&
289 tmp->oe_start <= ext->oe_end)
295 static void osc_extent_state_set(struct osc_extent *ext, int state)
297 LASSERT(osc_object_is_locked(ext->oe_obj));
298 LASSERT(state >= OES_INV && state < OES_STATE_MAX);
300 /* Never try to sanity check a state changing extent :-) */
301 /* LASSERT(sanity_check_nolock(ext) == 0); */
303 /* TODO: validate the state machine */
304 ext->oe_state = state;
305 wake_up_all(&ext->oe_waitq);
308 static struct osc_extent *osc_extent_alloc(struct osc_object *obj)
310 struct osc_extent *ext;
312 OBD_SLAB_ALLOC_PTR_GFP(ext, osc_extent_kmem, GFP_IOFS);
316 RB_CLEAR_NODE(&ext->oe_node);
318 atomic_set(&ext->oe_refc, 1);
319 atomic_set(&ext->oe_users, 0);
320 INIT_LIST_HEAD(&ext->oe_link);
321 ext->oe_state = OES_INV;
322 INIT_LIST_HEAD(&ext->oe_pages);
323 init_waitqueue_head(&ext->oe_waitq);
324 ext->oe_osclock = NULL;
329 static void osc_extent_free(struct osc_extent *ext)
331 OBD_SLAB_FREE_PTR(ext, osc_extent_kmem);
334 static struct osc_extent *osc_extent_get(struct osc_extent *ext)
336 LASSERT(atomic_read(&ext->oe_refc) >= 0);
337 atomic_inc(&ext->oe_refc);
341 static void osc_extent_put(const struct lu_env *env, struct osc_extent *ext)
343 LASSERT(atomic_read(&ext->oe_refc) > 0);
344 if (atomic_dec_and_test(&ext->oe_refc)) {
345 LASSERT(list_empty(&ext->oe_link));
346 LASSERT(atomic_read(&ext->oe_users) == 0);
347 LASSERT(ext->oe_state == OES_INV);
348 LASSERT(!ext->oe_intree);
350 if (ext->oe_osclock) {
351 cl_lock_put(env, ext->oe_osclock);
352 ext->oe_osclock = NULL;
354 osc_extent_free(ext);
359 * osc_extent_put_trust() is a special version of osc_extent_put() when
360 * it's known that the caller is not the last user. This is to address the
361 * problem of lacking of lu_env ;-).
363 static void osc_extent_put_trust(struct osc_extent *ext)
365 LASSERT(atomic_read(&ext->oe_refc) > 1);
366 LASSERT(osc_object_is_locked(ext->oe_obj));
367 atomic_dec(&ext->oe_refc);
371 * Return the extent which includes pgoff @index, or return the greatest
372 * previous extent in the tree.
374 static struct osc_extent *osc_extent_search(struct osc_object *obj,
377 struct rb_node *n = obj->oo_root.rb_node;
378 struct osc_extent *tmp, *p = NULL;
380 LASSERT(osc_object_is_locked(obj));
383 if (index < tmp->oe_start) {
385 } else if (index > tmp->oe_end) {
396 * Return the extent covering @index, otherwise return NULL.
397 * caller must have held object lock.
399 static struct osc_extent *osc_extent_lookup(struct osc_object *obj,
402 struct osc_extent *ext;
404 ext = osc_extent_search(obj, index);
405 if (ext != NULL && ext->oe_start <= index && index <= ext->oe_end)
406 return osc_extent_get(ext);
410 /* caller must have held object lock. */
411 static void osc_extent_insert(struct osc_object *obj, struct osc_extent *ext)
413 struct rb_node **n = &obj->oo_root.rb_node;
414 struct rb_node *parent = NULL;
415 struct osc_extent *tmp;
417 LASSERT(ext->oe_intree == 0);
418 LASSERT(ext->oe_obj == obj);
419 LASSERT(osc_object_is_locked(obj));
424 if (ext->oe_end < tmp->oe_start)
426 else if (ext->oe_start > tmp->oe_end)
429 EASSERTF(0, tmp, EXTSTR"\n", EXTPARA(ext));
431 rb_link_node(&ext->oe_node, parent, n);
432 rb_insert_color(&ext->oe_node, &obj->oo_root);
437 /* caller must have held object lock. */
438 static void osc_extent_erase(struct osc_extent *ext)
440 struct osc_object *obj = ext->oe_obj;
441 LASSERT(osc_object_is_locked(obj));
442 if (ext->oe_intree) {
443 rb_erase(&ext->oe_node, &obj->oo_root);
445 /* rbtree held a refcount */
446 osc_extent_put_trust(ext);
450 static struct osc_extent *osc_extent_hold(struct osc_extent *ext)
452 struct osc_object *obj = ext->oe_obj;
454 LASSERT(osc_object_is_locked(obj));
455 LASSERT(ext->oe_state == OES_ACTIVE || ext->oe_state == OES_CACHE);
456 if (ext->oe_state == OES_CACHE) {
457 osc_extent_state_set(ext, OES_ACTIVE);
458 osc_update_pending(obj, OBD_BRW_WRITE, -ext->oe_nr_pages);
460 atomic_inc(&ext->oe_users);
461 list_del_init(&ext->oe_link);
462 return osc_extent_get(ext);
465 static void __osc_extent_remove(struct osc_extent *ext)
467 LASSERT(osc_object_is_locked(ext->oe_obj));
468 LASSERT(list_empty(&ext->oe_pages));
469 osc_extent_erase(ext);
470 list_del_init(&ext->oe_link);
471 osc_extent_state_set(ext, OES_INV);
472 OSC_EXTENT_DUMP(D_CACHE, ext, "destroyed.\n");
475 static void osc_extent_remove(struct osc_extent *ext)
477 struct osc_object *obj = ext->oe_obj;
479 osc_object_lock(obj);
480 __osc_extent_remove(ext);
481 osc_object_unlock(obj);
485 * This function is used to merge extents to get better performance. It checks
486 * if @cur and @victim are contiguous at chunk level.
488 static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
489 struct osc_extent *victim)
491 struct osc_object *obj = cur->oe_obj;
496 LASSERT(cur->oe_state == OES_CACHE);
497 LASSERT(osc_object_is_locked(obj));
501 if (victim->oe_state != OES_CACHE || victim->oe_fsync_wait)
504 if (cur->oe_max_end != victim->oe_max_end)
507 LASSERT(cur->oe_osclock == victim->oe_osclock);
508 ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_CACHE_SHIFT;
509 chunk_start = cur->oe_start >> ppc_bits;
510 chunk_end = cur->oe_end >> ppc_bits;
511 if (chunk_start != (victim->oe_end >> ppc_bits) + 1 &&
512 chunk_end + 1 != victim->oe_start >> ppc_bits)
515 OSC_EXTENT_DUMP(D_CACHE, victim, "will be merged by %p.\n", cur);
517 cur->oe_start = min(cur->oe_start, victim->oe_start);
518 cur->oe_end = max(cur->oe_end, victim->oe_end);
519 cur->oe_grants += victim->oe_grants;
520 cur->oe_nr_pages += victim->oe_nr_pages;
521 /* only the following bits are needed to merge */
522 cur->oe_urgent |= victim->oe_urgent;
523 cur->oe_memalloc |= victim->oe_memalloc;
524 list_splice_init(&victim->oe_pages, &cur->oe_pages);
525 list_del_init(&victim->oe_link);
526 victim->oe_nr_pages = 0;
528 osc_extent_get(victim);
529 __osc_extent_remove(victim);
530 osc_extent_put(env, victim);
532 OSC_EXTENT_DUMP(D_CACHE, cur, "after merging %p.\n", victim);
537 * Drop user count of osc_extent, and unplug IO asynchronously.
539 int osc_extent_release(const struct lu_env *env, struct osc_extent *ext)
541 struct osc_object *obj = ext->oe_obj;
545 LASSERT(atomic_read(&ext->oe_users) > 0);
546 LASSERT(sanity_check(ext) == 0);
547 LASSERT(ext->oe_grants > 0);
549 if (atomic_dec_and_lock(&ext->oe_users, &obj->oo_lock)) {
550 LASSERT(ext->oe_state == OES_ACTIVE);
551 if (ext->oe_trunc_pending) {
552 /* a truncate process is waiting for this extent.
553 * This may happen due to a race, check
554 * osc_cache_truncate_start(). */
555 osc_extent_state_set(ext, OES_TRUNC);
556 ext->oe_trunc_pending = 0;
558 osc_extent_state_set(ext, OES_CACHE);
559 osc_update_pending(obj, OBD_BRW_WRITE,
562 /* try to merge the previous and next extent. */
563 osc_extent_merge(env, ext, prev_extent(ext));
564 osc_extent_merge(env, ext, next_extent(ext));
567 list_move_tail(&ext->oe_link,
568 &obj->oo_urgent_exts);
570 osc_object_unlock(obj);
572 osc_io_unplug_async(env, osc_cli(obj), obj);
574 osc_extent_put(env, ext);
578 static inline int overlapped(struct osc_extent *ex1, struct osc_extent *ex2)
580 return !(ex1->oe_end < ex2->oe_start || ex2->oe_end < ex1->oe_start);
584 * Find or create an extent which includes @index, core function to manage
587 struct osc_extent *osc_extent_find(const struct lu_env *env,
588 struct osc_object *obj, pgoff_t index,
592 struct client_obd *cli = osc_cli(obj);
593 struct cl_lock *lock;
594 struct osc_extent *cur;
595 struct osc_extent *ext;
596 struct osc_extent *conflict = NULL;
597 struct osc_extent *found = NULL;
600 int max_pages; /* max_pages_per_rpc */
602 int ppc_bits; /* pages per chunk bits */
607 cur = osc_extent_alloc(obj);
609 RETURN(ERR_PTR(-ENOMEM));
611 lock = cl_lock_at_pgoff(env, osc2cl(obj), index, NULL, 1, 0);
612 LASSERT(lock != NULL);
613 LASSERT(lock->cll_descr.cld_mode >= CLM_WRITE);
615 LASSERT(cli->cl_chunkbits >= PAGE_CACHE_SHIFT);
616 ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
617 chunk_mask = ~((1 << ppc_bits) - 1);
618 chunksize = 1 << cli->cl_chunkbits;
619 chunk = index >> ppc_bits;
621 /* align end to rpc edge, rpc size may not be a power 2 integer. */
622 max_pages = cli->cl_max_pages_per_rpc;
623 LASSERT((max_pages & ~chunk_mask) == 0);
624 max_end = index - (index % max_pages) + max_pages - 1;
625 max_end = min_t(pgoff_t, max_end, lock->cll_descr.cld_end);
627 /* initialize new extent by parameters so far */
628 cur->oe_max_end = max_end;
629 cur->oe_start = index & chunk_mask;
630 cur->oe_end = ((index + ~chunk_mask + 1) & chunk_mask) - 1;
631 if (cur->oe_start < lock->cll_descr.cld_start)
632 cur->oe_start = lock->cll_descr.cld_start;
633 if (cur->oe_end > max_end)
634 cur->oe_end = max_end;
635 cur->oe_osclock = lock;
637 cur->oe_mppr = max_pages;
639 /* grants has been allocated by caller */
640 LASSERTF(*grants >= chunksize + cli->cl_extent_tax,
641 "%u/%u/%u.\n", *grants, chunksize, cli->cl_extent_tax);
642 LASSERTF((max_end - cur->oe_start) < max_pages, EXTSTR"\n",
646 osc_object_lock(obj);
647 ext = osc_extent_search(obj, cur->oe_start);
649 ext = first_extent(obj);
650 while (ext != NULL) {
651 loff_t ext_chk_start = ext->oe_start >> ppc_bits;
652 loff_t ext_chk_end = ext->oe_end >> ppc_bits;
654 LASSERT(sanity_check_nolock(ext) == 0);
655 if (chunk > ext_chk_end + 1)
658 /* if covering by different locks, no chance to match */
659 if (lock != ext->oe_osclock) {
660 EASSERTF(!overlapped(ext, cur), ext,
661 EXTSTR"\n", EXTPARA(cur));
663 ext = next_extent(ext);
667 /* discontiguous chunks? */
668 if (chunk + 1 < ext_chk_start) {
669 ext = next_extent(ext);
673 /* ok, from now on, ext and cur have these attrs:
674 * 1. covered by the same lock
675 * 2. contiguous at chunk level or overlapping. */
677 if (overlapped(ext, cur)) {
678 /* cur is the minimum unit, so overlapping means
680 EASSERTF((ext->oe_start <= cur->oe_start &&
681 ext->oe_end >= cur->oe_end),
682 ext, EXTSTR"\n", EXTPARA(cur));
684 if (ext->oe_state > OES_CACHE || ext->oe_fsync_wait) {
685 /* for simplicity, we wait for this extent to
686 * finish before going forward. */
687 conflict = osc_extent_get(ext);
691 found = osc_extent_hold(ext);
695 /* non-overlapped extent */
696 if (ext->oe_state != OES_CACHE || ext->oe_fsync_wait) {
697 /* we can't do anything for a non OES_CACHE extent, or
698 * if there is someone waiting for this extent to be
699 * flushed, try next one. */
700 ext = next_extent(ext);
704 /* check if they belong to the same rpc slot before trying to
705 * merge. the extents are not overlapped and contiguous at
706 * chunk level to get here. */
707 if (ext->oe_max_end != max_end) {
708 /* if they don't belong to the same RPC slot or
709 * max_pages_per_rpc has ever changed, do not merge. */
710 ext = next_extent(ext);
714 /* it's required that an extent must be contiguous at chunk
715 * level so that we know the whole extent is covered by grant
716 * (the pages in the extent are NOT required to be contiguous).
717 * Otherwise, it will be too much difficult to know which
718 * chunks have grants allocated. */
720 /* try to do front merge - extend ext's start */
721 if (chunk + 1 == ext_chk_start) {
722 /* ext must be chunk size aligned */
723 EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
725 /* pull ext's start back to cover cur */
726 ext->oe_start = cur->oe_start;
727 ext->oe_grants += chunksize;
728 *grants -= chunksize;
730 found = osc_extent_hold(ext);
731 } else if (chunk == ext_chk_end + 1) {
733 ext->oe_end = cur->oe_end;
734 ext->oe_grants += chunksize;
735 *grants -= chunksize;
737 /* try to merge with the next one because we just fill
739 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
740 /* we can save extent tax from next extent */
741 *grants += cli->cl_extent_tax;
743 found = osc_extent_hold(ext);
748 ext = next_extent(ext);
751 osc_extent_tree_dump(D_CACHE, obj);
753 LASSERT(conflict == NULL);
754 if (!IS_ERR(found)) {
755 LASSERT(found->oe_osclock == cur->oe_osclock);
756 OSC_EXTENT_DUMP(D_CACHE, found,
757 "found caching ext for %lu.\n", index);
759 } else if (conflict == NULL) {
760 /* create a new extent */
761 EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
762 cur->oe_grants = chunksize + cli->cl_extent_tax;
763 *grants -= cur->oe_grants;
764 LASSERT(*grants >= 0);
766 cur->oe_state = OES_CACHE;
767 found = osc_extent_hold(cur);
768 osc_extent_insert(obj, cur);
769 OSC_EXTENT_DUMP(D_CACHE, cur, "add into tree %lu/%lu.\n",
770 index, lock->cll_descr.cld_end);
772 osc_object_unlock(obj);
774 if (conflict != NULL) {
775 LASSERT(found == NULL);
777 /* waiting for IO to finish. Please notice that it's impossible
778 * to be an OES_TRUNC extent. */
779 rc = osc_extent_wait(env, conflict, OES_INV);
780 osc_extent_put(env, conflict);
783 GOTO(out, found = ERR_PTR(rc));
790 osc_extent_put(env, cur);
791 LASSERT(*grants >= 0);
796 * Called when IO is finished to an extent.
798 int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
801 struct client_obd *cli = osc_cli(ext->oe_obj);
802 struct osc_async_page *oap;
803 struct osc_async_page *tmp;
804 int nr_pages = ext->oe_nr_pages;
806 int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
811 OSC_EXTENT_DUMP(D_CACHE, ext, "extent finished.\n");
813 ext->oe_rc = rc ?: ext->oe_nr_pages;
814 EASSERT(ergo(rc == 0, ext->oe_state == OES_RPC), ext);
816 osc_lru_add_batch(cli, &ext->oe_pages);
817 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
819 list_del_init(&oap->oap_rpc_item);
820 list_del_init(&oap->oap_pending_item);
821 if (last_off <= oap->oap_obj_off) {
822 last_off = oap->oap_obj_off;
823 last_count = oap->oap_count;
827 osc_ap_completion(env, cli, oap, sent, rc);
829 EASSERT(ext->oe_nr_pages == 0, ext);
832 lost_grant = ext->oe_grants;
833 } else if (blocksize < PAGE_CACHE_SIZE &&
834 last_count != PAGE_CACHE_SIZE) {
835 /* For short writes we shouldn't count parts of pages that
836 * span a whole chunk on the OST side, or our accounting goes
837 * wrong. Should match the code in filter_grant_check. */
838 int offset = last_off & ~CFS_PAGE_MASK;
839 int count = last_count + (offset & (blocksize - 1));
840 int end = (offset + last_count) & (blocksize - 1);
842 count += blocksize - end;
844 lost_grant = PAGE_CACHE_SIZE - count;
846 if (ext->oe_grants > 0)
847 osc_free_grant(cli, nr_pages, lost_grant);
849 osc_extent_remove(ext);
850 /* put the refcount for RPC */
851 osc_extent_put(env, ext);
855 static int extent_wait_cb(struct osc_extent *ext, int state)
859 osc_object_lock(ext->oe_obj);
860 ret = ext->oe_state == state;
861 osc_object_unlock(ext->oe_obj);
867 * Wait for the extent's state to become @state.
869 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
872 struct osc_object *obj = ext->oe_obj;
873 struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(600), NULL,
874 LWI_ON_SIGNAL_NOOP, NULL);
878 osc_object_lock(obj);
879 LASSERT(sanity_check_nolock(ext) == 0);
880 /* `Kick' this extent only if the caller is waiting for it to be
882 if (state == OES_INV && !ext->oe_urgent && !ext->oe_hp) {
883 if (ext->oe_state == OES_ACTIVE) {
885 } else if (ext->oe_state == OES_CACHE) {
887 osc_extent_hold(ext);
891 osc_object_unlock(obj);
893 osc_extent_release(env, ext);
895 /* wait for the extent until its state becomes @state */
896 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state), &lwi);
897 if (rc == -ETIMEDOUT) {
898 OSC_EXTENT_DUMP(D_ERROR, ext,
899 "%s: wait ext to %d timedout, recovery in progress?\n",
900 osc_export(obj)->exp_obd->obd_name, state);
902 lwi = LWI_INTR(NULL, NULL);
903 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state),
906 if (rc == 0 && ext->oe_rc < 0)
912 * Discard pages with index greater than @size. If @ext is overlapped with
913 * @size, then partial truncate happens.
915 static int osc_extent_truncate(struct osc_extent *ext, pgoff_t trunc_index,
918 struct cl_env_nest nest;
921 struct osc_object *obj = ext->oe_obj;
922 struct client_obd *cli = osc_cli(obj);
923 struct osc_async_page *oap;
924 struct osc_async_page *tmp;
925 int pages_in_chunk = 0;
926 int ppc_bits = cli->cl_chunkbits -
928 __u64 trunc_chunk = trunc_index >> ppc_bits;
934 LASSERT(sanity_check(ext) == 0);
935 LASSERT(ext->oe_state == OES_TRUNC);
936 LASSERT(!ext->oe_urgent);
938 /* Request new lu_env.
939 * We can't use that env from osc_cache_truncate_start() because
940 * it's from lov_io_sub and not fully initialized. */
941 env = cl_env_nested_get(&nest);
942 io = &osc_env_info(env)->oti_io;
943 io->ci_obj = cl_object_top(osc2cl(obj));
944 rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
948 /* discard all pages with index greater then trunc_index */
949 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
951 pgoff_t index = osc_index(oap2osc(oap));
952 struct cl_page *page = oap2cl_page(oap);
954 LASSERT(list_empty(&oap->oap_rpc_item));
956 /* only discard the pages with their index greater than
957 * trunc_index, and ... */
958 if (index < trunc_index ||
959 (index == trunc_index && partial)) {
960 /* accounting how many pages remaining in the chunk
961 * so that we can calculate grants correctly. */
962 if (index >> ppc_bits == trunc_chunk)
967 list_del_init(&oap->oap_pending_item);
970 lu_ref_add(&page->cp_reference, "truncate", current);
972 if (cl_page_own(env, io, page) == 0) {
973 cl_page_discard(env, io, page);
974 cl_page_disown(env, io, page);
976 LASSERT(page->cp_state == CPS_FREEING);
980 lu_ref_del(&page->cp_reference, "truncate", current);
981 cl_page_put(env, page);
986 EASSERTF(ergo(ext->oe_start >= trunc_index + !!partial,
987 ext->oe_nr_pages == 0),
988 ext, "trunc_index %lu, partial %d\n", trunc_index, partial);
990 osc_object_lock(obj);
991 if (ext->oe_nr_pages == 0) {
992 LASSERT(pages_in_chunk == 0);
993 grants = ext->oe_grants;
995 } else { /* calculate how many grants we can free */
996 int chunks = (ext->oe_end >> ppc_bits) - trunc_chunk;
1000 /* if there is no pages in this chunk, we can also free grants
1001 * for the last chunk */
1002 if (pages_in_chunk == 0) {
1003 /* if this is the 1st chunk and no pages in this chunk,
1004 * ext->oe_nr_pages must be zero, so we should be in
1005 * the other if-clause. */
1006 LASSERT(trunc_chunk > 0);
1011 /* this is what we can free from this extent */
1012 grants = chunks << cli->cl_chunkbits;
1013 ext->oe_grants -= grants;
1014 last_index = ((trunc_chunk + 1) << ppc_bits) - 1;
1015 ext->oe_end = min(last_index, ext->oe_max_end);
1016 LASSERT(ext->oe_end >= ext->oe_start);
1017 LASSERT(ext->oe_grants > 0);
1019 osc_object_unlock(obj);
1021 if (grants > 0 || nr_pages > 0)
1022 osc_free_grant(cli, nr_pages, grants);
1025 cl_io_fini(env, io);
1026 cl_env_nested_put(&nest, env);
1031 * This function is used to make the extent prepared for transfer.
1032 * A race with flusing page - ll_writepage() has to be handled cautiously.
1034 static int osc_extent_make_ready(const struct lu_env *env,
1035 struct osc_extent *ext)
1037 struct osc_async_page *oap;
1038 struct osc_async_page *last = NULL;
1039 struct osc_object *obj = ext->oe_obj;
1044 /* we're going to grab page lock, so object lock must not be taken. */
1045 LASSERT(sanity_check(ext) == 0);
1046 /* in locking state, any process should not touch this extent. */
1047 EASSERT(ext->oe_state == OES_LOCKING, ext);
1048 EASSERT(ext->oe_owner != NULL, ext);
1050 OSC_EXTENT_DUMP(D_CACHE, ext, "make ready\n");
1052 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1054 if (last == NULL || last->oap_obj_off < oap->oap_obj_off)
1057 /* checking ASYNC_READY is race safe */
1058 if ((oap->oap_async_flags & ASYNC_READY) != 0)
1061 rc = osc_make_ready(env, oap, OBD_BRW_WRITE);
1064 spin_lock(&oap->oap_lock);
1065 oap->oap_async_flags |= ASYNC_READY;
1066 spin_unlock(&oap->oap_lock);
1069 LASSERT((oap->oap_async_flags & ASYNC_READY) != 0);
1072 LASSERTF(0, "unknown return code: %d\n", rc);
1076 LASSERT(page_count == ext->oe_nr_pages);
1077 LASSERT(last != NULL);
1078 /* the last page is the only one we need to refresh its count by
1079 * the size of file. */
1080 if (!(last->oap_async_flags & ASYNC_COUNT_STABLE)) {
1081 last->oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE);
1082 LASSERT(last->oap_count > 0);
1083 LASSERT(last->oap_page_off + last->oap_count <= PAGE_CACHE_SIZE);
1084 spin_lock(&last->oap_lock);
1085 last->oap_async_flags |= ASYNC_COUNT_STABLE;
1086 spin_unlock(&last->oap_lock);
1089 /* for the rest of pages, we don't need to call osf_refresh_count()
1090 * because it's known they are not the last page */
1091 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1092 if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
1093 oap->oap_count = PAGE_CACHE_SIZE - oap->oap_page_off;
1094 spin_lock(&oap->oap_lock);
1095 oap->oap_async_flags |= ASYNC_COUNT_STABLE;
1096 spin_unlock(&oap->oap_lock);
1100 osc_object_lock(obj);
1101 osc_extent_state_set(ext, OES_RPC);
1102 osc_object_unlock(obj);
1103 /* get a refcount for RPC. */
1104 osc_extent_get(ext);
1110 * Quick and simple version of osc_extent_find(). This function is frequently
1111 * called to expand the extent for the same IO. To expand the extent, the
1112 * page index must be in the same or next chunk of ext->oe_end.
1114 static int osc_extent_expand(struct osc_extent *ext, pgoff_t index, int *grants)
1116 struct osc_object *obj = ext->oe_obj;
1117 struct client_obd *cli = osc_cli(obj);
1118 struct osc_extent *next;
1119 int ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
1120 pgoff_t chunk = index >> ppc_bits;
1123 int chunksize = 1 << cli->cl_chunkbits;
1127 LASSERT(ext->oe_max_end >= index && ext->oe_start <= index);
1128 osc_object_lock(obj);
1129 LASSERT(sanity_check_nolock(ext) == 0);
1130 end_chunk = ext->oe_end >> ppc_bits;
1131 if (chunk > end_chunk + 1)
1132 GOTO(out, rc = -ERANGE);
1134 if (end_chunk >= chunk)
1137 LASSERT(end_chunk + 1 == chunk);
1138 /* try to expand this extent to cover @index */
1139 end_index = min(ext->oe_max_end, ((chunk + 1) << ppc_bits) - 1);
1141 next = next_extent(ext);
1142 if (next != NULL && next->oe_start <= end_index)
1143 /* complex mode - overlapped with the next extent,
1144 * this case will be handled by osc_extent_find() */
1145 GOTO(out, rc = -EAGAIN);
1147 ext->oe_end = end_index;
1148 ext->oe_grants += chunksize;
1149 *grants -= chunksize;
1150 LASSERT(*grants >= 0);
1151 EASSERTF(osc_extent_is_overlapped(obj, ext) == 0, ext,
1152 "overlapped after expanding for %lu.\n", index);
1156 osc_object_unlock(obj);
1160 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
1161 const char *func, int line)
1163 struct osc_extent *ext;
1166 CDEBUG(level, "Dump object %p extents at %s:%d, mppr: %u.\n",
1167 obj, func, line, osc_cli(obj)->cl_max_pages_per_rpc);
1169 /* osc_object_lock(obj); */
1171 for (ext = first_extent(obj); ext != NULL; ext = next_extent(ext))
1172 OSC_EXTENT_DUMP(level, ext, "in tree %d.\n", cnt++);
1175 list_for_each_entry(ext, &obj->oo_hp_exts, oe_link)
1176 OSC_EXTENT_DUMP(level, ext, "hp %d.\n", cnt++);
1179 list_for_each_entry(ext, &obj->oo_urgent_exts, oe_link)
1180 OSC_EXTENT_DUMP(level, ext, "urgent %d.\n", cnt++);
1183 list_for_each_entry(ext, &obj->oo_reading_exts, oe_link)
1184 OSC_EXTENT_DUMP(level, ext, "reading %d.\n", cnt++);
1185 /* osc_object_unlock(obj); */
1188 /* ------------------ osc extent end ------------------ */
1190 static inline int osc_is_ready(struct osc_object *osc)
1192 return !list_empty(&osc->oo_ready_item) ||
1193 !list_empty(&osc->oo_hp_ready_item);
1196 #define OSC_IO_DEBUG(OSC, STR, args...) \
1197 CDEBUG(D_CACHE, "obj %p ready %d|%c|%c wr %d|%c|%c rd %d|%c " STR, \
1198 (OSC), osc_is_ready(OSC), \
1199 list_empty_marker(&(OSC)->oo_hp_ready_item), \
1200 list_empty_marker(&(OSC)->oo_ready_item), \
1201 atomic_read(&(OSC)->oo_nr_writes), \
1202 list_empty_marker(&(OSC)->oo_hp_exts), \
1203 list_empty_marker(&(OSC)->oo_urgent_exts), \
1204 atomic_read(&(OSC)->oo_nr_reads), \
1205 list_empty_marker(&(OSC)->oo_reading_exts), \
1208 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
1211 struct osc_page *opg = oap2osc_page(oap);
1212 struct cl_page *page = oap2cl_page(oap);
1215 LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
1218 result = cl_page_make_ready(env, page, CRT_WRITE);
1220 opg->ops_submit_time = cfs_time_current();
1224 static int osc_refresh_count(const struct lu_env *env,
1225 struct osc_async_page *oap, int cmd)
1227 struct osc_page *opg = oap2osc_page(oap);
1228 pgoff_t index = osc_index(oap2osc(oap));
1229 struct cl_object *obj;
1230 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
1235 /* readpage queues with _COUNT_STABLE, shouldn't get here. */
1236 LASSERT(!(cmd & OBD_BRW_READ));
1237 LASSERT(opg != NULL);
1238 obj = opg->ops_cl.cpl_obj;
1240 cl_object_attr_lock(obj);
1241 result = cl_object_attr_get(env, obj, attr);
1242 cl_object_attr_unlock(obj);
1245 kms = attr->cat_kms;
1246 if (cl_offset(obj, index) >= kms)
1247 /* catch race with truncate */
1249 else if (cl_offset(obj, index + 1) > kms)
1250 /* catch sub-page write at end of file */
1251 return kms % PAGE_CACHE_SIZE;
1253 return PAGE_CACHE_SIZE;
1256 static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
1259 struct osc_page *opg = oap2osc_page(oap);
1260 struct cl_page *page = oap2cl_page(oap);
1261 struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
1262 enum cl_req_type crt;
1267 cmd &= ~OBD_BRW_NOQUOTA;
1268 LASSERTF(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ),
1269 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1270 LASSERTF(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE),
1271 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1272 LASSERT(opg->ops_transfer_pinned);
1275 * page->cp_req can be NULL if io submission failed before
1276 * cl_req was allocated.
1278 if (page->cp_req != NULL)
1279 cl_req_page_done(env, page);
1280 LASSERT(page->cp_req == NULL);
1282 crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
1283 /* Clear opg->ops_transfer_pinned before VM lock is released. */
1284 opg->ops_transfer_pinned = 0;
1286 spin_lock(&obj->oo_seatbelt);
1287 LASSERT(opg->ops_submitter != NULL);
1288 LASSERT(!list_empty(&opg->ops_inflight));
1289 list_del_init(&opg->ops_inflight);
1290 opg->ops_submitter = NULL;
1291 spin_unlock(&obj->oo_seatbelt);
1293 opg->ops_submit_time = 0;
1294 srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
1297 if (rc == 0 && srvlock) {
1298 struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
1299 struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
1300 int bytes = oap->oap_count;
1302 if (crt == CRT_READ)
1303 stats->os_lockless_reads += bytes;
1305 stats->os_lockless_writes += bytes;
1309 * This has to be the last operation with the page, as locks are
1310 * released in cl_page_completion() and nothing except for the
1311 * reference counter protects page from concurrent reclaim.
1313 lu_ref_del(&page->cp_reference, "transfer", page);
1315 cl_page_completion(env, page, crt, rc);
1320 #define OSC_DUMP_GRANT(lvl, cli, fmt, args...) do { \
1321 struct client_obd *__tmp = (cli); \
1322 CDEBUG(lvl, "%s: grant { dirty: %ld/%ld dirty_pages: %d/%d " \
1323 "dropped: %ld avail: %ld, reserved: %ld, flight: %d }" \
1324 "lru {in list: %d, left: %d, waiters: %d }" fmt "\n", \
1325 __tmp->cl_import->imp_obd->obd_name, \
1326 __tmp->cl_dirty_pages, __tmp->cl_dirty_max_pages, \
1327 atomic_read(&obd_dirty_pages), obd_max_dirty_pages, \
1328 __tmp->cl_lost_grant, __tmp->cl_avail_grant, \
1329 __tmp->cl_reserved_grant, __tmp->cl_w_in_flight, \
1330 atomic_read(&__tmp->cl_lru_in_list), \
1331 atomic_read(&__tmp->cl_lru_busy), \
1332 atomic_read(&__tmp->cl_lru_shrinkers), ##args); \
1335 /* caller must hold loi_list_lock */
1336 static void osc_consume_write_grant(struct client_obd *cli,
1337 struct brw_page *pga)
1339 assert_spin_locked(&cli->cl_loi_list_lock.lock);
1340 LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
1341 atomic_inc(&obd_dirty_pages);
1342 cli->cl_dirty_pages++;
1343 pga->flag |= OBD_BRW_FROM_GRANT;
1344 CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
1345 PAGE_CACHE_SIZE, pga, pga->pg);
1346 osc_update_next_shrink(cli);
1349 /* the companion to osc_consume_write_grant, called when a brw has completed.
1350 * must be called with the loi lock held. */
1351 static void osc_release_write_grant(struct client_obd *cli,
1352 struct brw_page *pga)
1356 assert_spin_locked(&cli->cl_loi_list_lock.lock);
1357 if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
1362 pga->flag &= ~OBD_BRW_FROM_GRANT;
1363 atomic_dec(&obd_dirty_pages);
1364 cli->cl_dirty_pages--;
1365 if (pga->flag & OBD_BRW_NOCACHE) {
1366 pga->flag &= ~OBD_BRW_NOCACHE;
1367 atomic_dec(&obd_dirty_transit_pages);
1368 cli->cl_dirty_transit--;
1374 * To avoid sleeping with object lock held, it's good for us allocate enough
1375 * grants before entering into critical section.
1377 * client_obd_list_lock held by caller
1379 static int osc_reserve_grant(struct client_obd *cli, unsigned int bytes)
1383 if (cli->cl_avail_grant >= bytes) {
1384 cli->cl_avail_grant -= bytes;
1385 cli->cl_reserved_grant += bytes;
1391 static void __osc_unreserve_grant(struct client_obd *cli,
1392 unsigned int reserved, unsigned int unused)
1394 /* it's quite normal for us to get more grant than reserved.
1395 * Thinking about a case that two extents merged by adding a new
1396 * chunk, we can save one extent tax. If extent tax is greater than
1397 * one chunk, we can save more grant by adding a new chunk */
1398 cli->cl_reserved_grant -= reserved;
1399 if (unused > reserved) {
1400 cli->cl_avail_grant += reserved;
1401 cli->cl_lost_grant += unused - reserved;
1403 cli->cl_avail_grant += unused;
1407 void osc_unreserve_grant(struct client_obd *cli,
1408 unsigned int reserved, unsigned int unused)
1410 client_obd_list_lock(&cli->cl_loi_list_lock);
1411 __osc_unreserve_grant(cli, reserved, unused);
1413 osc_wake_cache_waiters(cli);
1414 client_obd_list_unlock(&cli->cl_loi_list_lock);
1418 * Free grant after IO is finished or canceled.
1420 * @lost_grant is used to remember how many grants we have allocated but not
1421 * used, we should return these grants to OST. There're two cases where grants
1424 * 2. blocksize at OST is less than PAGE_CACHE_SIZE and a partial page was
1425 * written. In this case OST may use less chunks to serve this partial
1426 * write. OSTs don't actually know the page size on the client side. so
1427 * clients have to calculate lost grant by the blocksize on the OST.
1428 * See filter_grant_check() for details.
1430 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
1431 unsigned int lost_grant)
1433 int grant = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
1435 client_obd_list_lock(&cli->cl_loi_list_lock);
1436 atomic_sub(nr_pages, &obd_dirty_pages);
1437 cli->cl_dirty_pages -= nr_pages;
1438 cli->cl_lost_grant += lost_grant;
1439 if (cli->cl_avail_grant < grant && cli->cl_lost_grant >= grant) {
1440 /* borrow some grant from truncate to avoid the case that
1441 * truncate uses up all avail grant */
1442 cli->cl_lost_grant -= grant;
1443 cli->cl_avail_grant += grant;
1445 osc_wake_cache_waiters(cli);
1446 client_obd_list_unlock(&cli->cl_loi_list_lock);
1447 CDEBUG(D_CACHE, "lost %u grant: %lu avail: %lu dirty: %lu\n",
1448 lost_grant, cli->cl_lost_grant,
1449 cli->cl_avail_grant, cli->cl_dirty_pages << PAGE_CACHE_SHIFT);
1453 * The companion to osc_enter_cache(), called when @oap is no longer part of
1454 * the dirty accounting due to error.
1456 static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap)
1458 client_obd_list_lock(&cli->cl_loi_list_lock);
1459 osc_release_write_grant(cli, &oap->oap_brw_page);
1460 client_obd_list_unlock(&cli->cl_loi_list_lock);
1464 * Non-blocking version of osc_enter_cache() that consumes grant only when it
1467 static int osc_enter_cache_try(struct client_obd *cli,
1468 struct osc_async_page *oap,
1469 int bytes, int transient)
1473 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d", bytes);
1475 rc = osc_reserve_grant(cli, bytes);
1479 if (cli->cl_dirty_pages < cli->cl_dirty_max_pages &&
1480 1 + atomic_read(&obd_dirty_pages) <= obd_max_dirty_pages) {
1481 osc_consume_write_grant(cli, &oap->oap_brw_page);
1483 cli->cl_dirty_transit++;
1484 atomic_inc(&obd_dirty_transit_pages);
1485 oap->oap_brw_flags |= OBD_BRW_NOCACHE;
1489 __osc_unreserve_grant(cli, bytes, bytes);
1495 static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
1498 client_obd_list_lock(&cli->cl_loi_list_lock);
1499 rc = list_empty(&ocw->ocw_entry);
1500 client_obd_list_unlock(&cli->cl_loi_list_lock);
1505 * The main entry to reserve dirty page accounting. Usually the grant reserved
1506 * in this function will be freed in bulk in osc_free_grant() unless it fails
1507 * to add osc cache, in that case, it will be freed in osc_exit_cache().
1509 * The process will be put into sleep if it's already run out of grant.
1511 static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
1512 struct osc_async_page *oap, int bytes)
1514 struct osc_object *osc = oap->oap_obj;
1515 struct lov_oinfo *loi = osc->oo_oinfo;
1516 struct osc_cache_waiter ocw;
1517 struct l_wait_info lwi;
1521 lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(AT_OFF ? obd_timeout : at_max),
1522 NULL, LWI_ON_SIGNAL_NOOP, NULL);
1524 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d", bytes);
1526 client_obd_list_lock(&cli->cl_loi_list_lock);
1528 /* force the caller to try sync io. this can jump the list
1529 * of queued writes and create a discontiguous rpc stream */
1530 if (OBD_FAIL_CHECK(OBD_FAIL_OSC_NO_GRANT) ||
1531 cli->cl_dirty_max_pages == 0 ||
1532 cli->cl_ar.ar_force_sync || loi->loi_ar.ar_force_sync) {
1533 OSC_DUMP_GRANT(D_CACHE, cli, "forced sync i/o");
1534 GOTO(out, rc = -EDQUOT);
1537 /* Hopefully normal case - cache space and write credits available */
1538 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1539 OSC_DUMP_GRANT(D_CACHE, cli, "granted from cache");
1543 /* We can get here for two reasons: too many dirty pages in cache, or
1544 * run out of grants. In both cases we should write dirty pages out.
1545 * Adding a cache waiter will trigger urgent write-out no matter what
1547 * The exiting condition is no avail grants and no dirty pages caching,
1548 * that really means there is no space on the OST. */
1549 init_waitqueue_head(&ocw.ocw_waitq);
1551 ocw.ocw_grant = bytes;
1552 while (cli->cl_dirty_pages > 0 || cli->cl_w_in_flight > 0) {
1553 list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
1555 client_obd_list_unlock(&cli->cl_loi_list_lock);
1557 osc_io_unplug_async(env, cli, NULL);
1559 CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
1560 cli->cl_import->imp_obd->obd_name, &ocw, oap);
1562 rc = l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
1564 client_obd_list_lock(&cli->cl_loi_list_lock);
1567 /* l_wait_event is interrupted by signal or timed out */
1568 list_del_init(&ocw.ocw_entry);
1571 LASSERT(list_empty(&ocw.ocw_entry));
1576 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1584 OSC_DUMP_GRANT(D_CACHE, cli, "finally got grant space");
1587 OSC_DUMP_GRANT(D_CACHE, cli, "timeout, fall back to sync i/o");
1588 osc_extent_tree_dump(D_CACHE, osc);
1589 /* fall back to synchronous I/O */
1593 /* Ensures restartability - LU-3581 */
1594 OSC_DUMP_GRANT(D_CACHE, cli, "interrupted");
1598 OSC_DUMP_GRANT(D_CACHE, cli, "no grant space, fall back to sync"
1602 CDEBUG(D_CACHE, "%s: event for cache space @ %p never arrived "
1603 "due to %d, fall back to sync i/o\n",
1604 cli->cl_import->imp_obd->obd_name, &ocw, rc);
1605 /* fall back to synchronous I/O */
1611 client_obd_list_unlock(&cli->cl_loi_list_lock);
1615 /* caller must hold loi_list_lock */
1616 void osc_wake_cache_waiters(struct client_obd *cli)
1618 struct list_head *l, *tmp;
1619 struct osc_cache_waiter *ocw;
1622 list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
1623 ocw = list_entry(l, struct osc_cache_waiter, ocw_entry);
1624 list_del_init(&ocw->ocw_entry);
1626 ocw->ocw_rc = -EDQUOT;
1627 /* we can't dirty more */
1628 if ((cli->cl_dirty_pages >= cli->cl_dirty_max_pages) ||
1629 (1 + atomic_read(&obd_dirty_pages) > obd_max_dirty_pages)) {
1630 CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
1631 "osc max %ld, sys max %d\n", cli->cl_dirty_pages,
1632 cli->cl_dirty_max_pages, obd_max_dirty_pages);
1636 if (osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
1639 CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
1640 ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
1642 wake_up(&ocw->ocw_waitq);
1648 static int osc_max_rpc_in_flight(struct client_obd *cli, struct osc_object *osc)
1650 int hprpc = !!list_empty(&osc->oo_hp_exts);
1651 return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
1654 /* This maintains the lists of pending pages to read/write for a given object
1655 * (lop). This is used by osc_check_rpcs->osc_next_obj() and osc_list_maint()
1656 * to quickly find objects that are ready to send an RPC. */
1657 static int osc_makes_rpc(struct client_obd *cli, struct osc_object *osc,
1660 int invalid_import = 0;
1663 /* if we have an invalid import we want to drain the queued pages
1664 * by forcing them through rpcs that immediately fail and complete
1665 * the pages. recovery relies on this to empty the queued pages
1666 * before canceling the locks and evicting down the llite pages */
1667 if ((cli->cl_import == NULL || cli->cl_import->imp_invalid))
1670 if (cmd & OBD_BRW_WRITE) {
1671 if (atomic_read(&osc->oo_nr_writes) == 0)
1673 if (invalid_import) {
1674 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1677 if (!list_empty(&osc->oo_hp_exts)) {
1678 CDEBUG(D_CACHE, "high prio request forcing RPC\n");
1681 if (!list_empty(&osc->oo_urgent_exts)) {
1682 CDEBUG(D_CACHE, "urgent request forcing RPC\n");
1685 /* trigger a write rpc stream as long as there are dirtiers
1686 * waiting for space. as they're waiting, they're not going to
1687 * create more pages to coalesce with what's waiting.. */
1688 if (!list_empty(&cli->cl_cache_waiters)) {
1689 CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
1692 if (atomic_read(&osc->oo_nr_writes) >=
1693 cli->cl_max_pages_per_rpc)
1696 if (atomic_read(&osc->oo_nr_reads) == 0)
1698 if (invalid_import) {
1699 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1702 /* all read are urgent. */
1703 if (!list_empty(&osc->oo_reading_exts))
1710 static void osc_update_pending(struct osc_object *obj, int cmd, int delta)
1712 struct client_obd *cli = osc_cli(obj);
1713 if (cmd & OBD_BRW_WRITE) {
1714 atomic_add(delta, &obj->oo_nr_writes);
1715 atomic_add(delta, &cli->cl_pending_w_pages);
1716 LASSERT(atomic_read(&obj->oo_nr_writes) >= 0);
1718 atomic_add(delta, &obj->oo_nr_reads);
1719 atomic_add(delta, &cli->cl_pending_r_pages);
1720 LASSERT(atomic_read(&obj->oo_nr_reads) >= 0);
1722 OSC_IO_DEBUG(obj, "update pending cmd %d delta %d.\n", cmd, delta);
1725 static int osc_makes_hprpc(struct osc_object *obj)
1727 return !list_empty(&obj->oo_hp_exts);
1730 static void on_list(struct list_head *item, struct list_head *list,
1733 if (list_empty(item) && should_be_on)
1734 list_add_tail(item, list);
1735 else if (!list_empty(item) && !should_be_on)
1736 list_del_init(item);
1739 /* maintain the osc's cli list membership invariants so that osc_send_oap_rpc
1740 * can find pages to build into rpcs quickly */
1741 static int __osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1743 if (osc_makes_hprpc(osc)) {
1745 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list, 0);
1746 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
1748 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
1749 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list,
1750 osc_makes_rpc(cli, osc, OBD_BRW_WRITE) ||
1751 osc_makes_rpc(cli, osc, OBD_BRW_READ));
1754 on_list(&osc->oo_write_item, &cli->cl_loi_write_list,
1755 atomic_read(&osc->oo_nr_writes) > 0);
1757 on_list(&osc->oo_read_item, &cli->cl_loi_read_list,
1758 atomic_read(&osc->oo_nr_reads) > 0);
1760 return osc_is_ready(osc);
1763 static int osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1767 client_obd_list_lock(&cli->cl_loi_list_lock);
1768 is_ready = __osc_list_maint(cli, osc);
1769 client_obd_list_unlock(&cli->cl_loi_list_lock);
1774 /* this is trying to propogate async writeback errors back up to the
1775 * application. As an async write fails we record the error code for later if
1776 * the app does an fsync. As long as errors persist we force future rpcs to be
1777 * sync so that the app can get a sync error and break the cycle of queueing
1778 * pages for which writeback will fail. */
1779 static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
1786 ar->ar_force_sync = 1;
1787 ar->ar_min_xid = ptlrpc_sample_next_xid();
1792 if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
1793 ar->ar_force_sync = 0;
1796 /* this must be called holding the loi list lock to give coverage to exit_cache,
1797 * async_flag maintenance, and oap_request */
1798 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
1799 struct osc_async_page *oap, int sent, int rc)
1801 struct osc_object *osc = oap->oap_obj;
1802 struct lov_oinfo *loi = osc->oo_oinfo;
1806 if (oap->oap_request != NULL) {
1807 xid = ptlrpc_req_xid(oap->oap_request);
1808 ptlrpc_req_finished(oap->oap_request);
1809 oap->oap_request = NULL;
1812 /* As the transfer for this page is being done, clear the flags */
1813 spin_lock(&oap->oap_lock);
1814 oap->oap_async_flags = 0;
1815 spin_unlock(&oap->oap_lock);
1816 oap->oap_interrupted = 0;
1818 if (oap->oap_cmd & OBD_BRW_WRITE && xid > 0) {
1819 client_obd_list_lock(&cli->cl_loi_list_lock);
1820 osc_process_ar(&cli->cl_ar, xid, rc);
1821 osc_process_ar(&loi->loi_ar, xid, rc);
1822 client_obd_list_unlock(&cli->cl_loi_list_lock);
1825 rc = osc_completion(env, oap, oap->oap_cmd, rc);
1827 CERROR("completion on oap %p obj %p returns %d.\n",
1834 * Try to add extent to one RPC. We need to think about the following things:
1835 * - # of pages must not be over max_pages_per_rpc
1836 * - extent must be compatible with previous ones
1838 static int try_to_add_extent_for_io(struct client_obd *cli,
1839 struct osc_extent *ext,
1840 struct list_head *rpclist,
1841 int *pc, unsigned int *max_pages)
1843 struct osc_extent *tmp;
1844 struct osc_async_page *oap = list_first_entry(&ext->oe_pages,
1845 struct osc_async_page,
1849 EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE),
1852 *max_pages = max(ext->oe_mppr, *max_pages);
1853 if (*pc + ext->oe_nr_pages > *max_pages)
1856 list_for_each_entry(tmp, rpclist, oe_link) {
1857 struct osc_async_page *oap2;
1858 oap2 = list_first_entry(&tmp->oe_pages, struct osc_async_page,
1860 EASSERT(tmp->oe_owner == current, tmp);
1862 if (overlapped(tmp, ext)) {
1863 OSC_EXTENT_DUMP(D_ERROR, tmp, "overlapped %p.\n", ext);
1867 if (oap2cl_page(oap)->cp_type != oap2cl_page(oap2)->cp_type) {
1868 CDEBUG(D_CACHE, "Do not permit different type of IO"
1869 " for a same RPC\n");
1873 if (tmp->oe_srvlock != ext->oe_srvlock ||
1874 !tmp->oe_grants != !ext->oe_grants)
1877 /* remove break for strict check */
1881 *pc += ext->oe_nr_pages;
1882 list_move_tail(&ext->oe_link, rpclist);
1883 ext->oe_owner = current;
1888 * In order to prevent multiple ptlrpcd from breaking contiguous extents,
1889 * get_write_extent() takes all appropriate extents in atomic.
1891 * The following policy is used to collect extents for IO:
1892 * 1. Add as many HP extents as possible;
1893 * 2. Add the first urgent extent in urgent extent list and take it out of
1895 * 3. Add subsequent extents of this urgent extent;
1896 * 4. If urgent list is not empty, goto 2;
1897 * 5. Traverse the extent tree from the 1st extent;
1898 * 6. Above steps exit if there is no space in this RPC.
1900 static int get_write_extents(struct osc_object *obj, struct list_head *rpclist)
1902 struct client_obd *cli = osc_cli(obj);
1903 struct osc_extent *ext;
1905 unsigned int max_pages = cli->cl_max_pages_per_rpc;
1907 LASSERT(osc_object_is_locked(obj));
1908 while (!list_empty(&obj->oo_hp_exts)) {
1909 ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
1911 LASSERT(ext->oe_state == OES_CACHE);
1912 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1915 EASSERT(ext->oe_nr_pages <= max_pages, ext);
1917 if (page_count == max_pages)
1920 while (!list_empty(&obj->oo_urgent_exts)) {
1921 ext = list_entry(obj->oo_urgent_exts.next,
1922 struct osc_extent, oe_link);
1923 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1927 if (!ext->oe_intree)
1930 while ((ext = next_extent(ext)) != NULL) {
1931 if ((ext->oe_state != OES_CACHE) ||
1932 (!list_empty(&ext->oe_link) &&
1933 ext->oe_owner != NULL))
1936 if (!try_to_add_extent_for_io(cli, ext, rpclist,
1937 &page_count, &max_pages))
1941 if (page_count == max_pages)
1944 ext = first_extent(obj);
1945 while (ext != NULL) {
1946 if ((ext->oe_state != OES_CACHE) ||
1947 /* this extent may be already in current rpclist */
1948 (!list_empty(&ext->oe_link) && ext->oe_owner != NULL)) {
1949 ext = next_extent(ext);
1953 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1957 ext = next_extent(ext);
1963 osc_send_write_rpc(const struct lu_env *env, struct client_obd *cli,
1964 struct osc_object *osc, pdl_policy_t pol)
1967 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
1968 struct osc_extent *ext;
1969 struct osc_extent *tmp;
1970 struct osc_extent *first = NULL;
1971 obd_count page_count = 0;
1976 LASSERT(osc_object_is_locked(osc));
1978 page_count = get_write_extents(osc, &rpclist);
1979 LASSERT(equi(page_count == 0, list_empty(&rpclist)));
1981 if (list_empty(&rpclist))
1984 osc_update_pending(osc, OBD_BRW_WRITE, -page_count);
1986 list_for_each_entry(ext, &rpclist, oe_link) {
1987 LASSERT(ext->oe_state == OES_CACHE ||
1988 ext->oe_state == OES_LOCK_DONE);
1989 if (ext->oe_state == OES_CACHE)
1990 osc_extent_state_set(ext, OES_LOCKING);
1992 osc_extent_state_set(ext, OES_RPC);
1995 /* we're going to grab page lock, so release object lock because
1996 * lock order is page lock -> object lock. */
1997 osc_object_unlock(osc);
1999 list_for_each_entry_safe(ext, tmp, &rpclist, oe_link) {
2000 if (ext->oe_state == OES_LOCKING) {
2001 rc = osc_extent_make_ready(env, ext);
2002 if (unlikely(rc < 0)) {
2003 list_del_init(&ext->oe_link);
2004 osc_extent_finish(env, ext, 0, rc);
2008 if (first == NULL) {
2010 srvlock = ext->oe_srvlock;
2012 LASSERT(srvlock == ext->oe_srvlock);
2016 if (!list_empty(&rpclist)) {
2017 LASSERT(page_count > 0);
2018 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_WRITE, pol);
2019 LASSERT(list_empty(&rpclist));
2022 osc_object_lock(osc);
2027 * prepare pages for ASYNC io and put pages in send queue.
2029 * \param cmd OBD_BRW_* macroses
2030 * \param lop pending pages
2032 * \return zero if no page added to send queue.
2033 * \return 1 if pages successfully added to send queue.
2034 * \return negative on errors.
2037 osc_send_read_rpc(const struct lu_env *env, struct client_obd *cli,
2038 struct osc_object *osc, pdl_policy_t pol)
2041 struct osc_extent *ext;
2042 struct osc_extent *next;
2043 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2045 unsigned int max_pages = cli->cl_max_pages_per_rpc;
2049 LASSERT(osc_object_is_locked(osc));
2050 list_for_each_entry_safe(ext, next,
2051 &osc->oo_reading_exts, oe_link) {
2052 EASSERT(ext->oe_state == OES_LOCK_DONE, ext);
2053 if (!try_to_add_extent_for_io(cli, ext, &rpclist, &page_count,
2056 osc_extent_state_set(ext, OES_RPC);
2057 EASSERT(ext->oe_nr_pages <= max_pages, ext);
2059 LASSERT(page_count <= max_pages);
2061 osc_update_pending(osc, OBD_BRW_READ, -page_count);
2063 if (!list_empty(&rpclist)) {
2064 osc_object_unlock(osc);
2066 LASSERT(page_count > 0);
2067 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_READ, pol);
2068 LASSERT(list_empty(&rpclist));
2070 osc_object_lock(osc);
2075 #define list_to_obj(list, item) ({ \
2076 struct list_head *__tmp = (list)->next; \
2077 list_del_init(__tmp); \
2078 list_entry(__tmp, struct osc_object, oo_##item); \
2081 /* This is called by osc_check_rpcs() to find which objects have pages that
2082 * we could be sending. These lists are maintained by osc_makes_rpc(). */
2083 static struct osc_object *osc_next_obj(struct client_obd *cli)
2087 /* First return objects that have blocked locks so that they
2088 * will be flushed quickly and other clients can get the lock,
2089 * then objects which have pages ready to be stuffed into RPCs */
2090 if (!list_empty(&cli->cl_loi_hp_ready_list))
2091 RETURN(list_to_obj(&cli->cl_loi_hp_ready_list, hp_ready_item));
2092 if (!list_empty(&cli->cl_loi_ready_list))
2093 RETURN(list_to_obj(&cli->cl_loi_ready_list, ready_item));
2095 /* then if we have cache waiters, return all objects with queued
2096 * writes. This is especially important when many small files
2097 * have filled up the cache and not been fired into rpcs because
2098 * they don't pass the nr_pending/object threshhold */
2099 if (!list_empty(&cli->cl_cache_waiters) &&
2100 !list_empty(&cli->cl_loi_write_list))
2101 RETURN(list_to_obj(&cli->cl_loi_write_list, write_item));
2103 /* then return all queued objects when we have an invalid import
2104 * so that they get flushed */
2105 if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
2106 if (!list_empty(&cli->cl_loi_write_list))
2107 RETURN(list_to_obj(&cli->cl_loi_write_list,
2109 if (!list_empty(&cli->cl_loi_read_list))
2110 RETURN(list_to_obj(&cli->cl_loi_read_list,
2116 /* called with the loi list lock held */
2117 static void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli,
2119 __must_hold(&cli->cl_loi_list_lock)
2121 struct osc_object *osc;
2125 while ((osc = osc_next_obj(cli)) != NULL) {
2126 struct cl_object *obj = osc2cl(osc);
2127 struct lu_ref_link link;
2129 OSC_IO_DEBUG(osc, "%lu in flight\n", rpcs_in_flight(cli));
2131 if (osc_max_rpc_in_flight(cli, osc)) {
2132 __osc_list_maint(cli, osc);
2137 client_obd_list_unlock(&cli->cl_loi_list_lock);
2138 lu_object_ref_add_at(&obj->co_lu, &link, "check", current);
2140 /* attempt some read/write balancing by alternating between
2141 * reads and writes in an object. The makes_rpc checks here
2142 * would be redundant if we were getting read/write work items
2143 * instead of objects. we don't want send_oap_rpc to drain a
2144 * partial read pending queue when we're given this object to
2145 * do io on writes while there are cache waiters */
2146 osc_object_lock(osc);
2147 if (osc_makes_rpc(cli, osc, OBD_BRW_WRITE)) {
2148 rc = osc_send_write_rpc(env, cli, osc, pol);
2150 CERROR("Write request failed with %d\n", rc);
2152 /* osc_send_write_rpc failed, mostly because of
2155 * It can't break here, because if:
2156 * - a page was submitted by osc_io_submit, so
2158 * - no request in flight
2159 * - no subsequent request
2160 * The system will be in live-lock state,
2161 * because there is no chance to call
2162 * osc_io_unplug() and osc_check_rpcs() any
2163 * more. pdflush can't help in this case,
2164 * because it might be blocked at grabbing
2165 * the page lock as we mentioned.
2167 * Anyway, continue to drain pages. */
2171 if (osc_makes_rpc(cli, osc, OBD_BRW_READ)) {
2172 rc = osc_send_read_rpc(env, cli, osc, pol);
2174 CERROR("Read request failed with %d\n", rc);
2176 osc_object_unlock(osc);
2178 osc_list_maint(cli, osc);
2179 lu_object_ref_del_at(&obj->co_lu, &link, "check", current);
2180 cl_object_put(env, obj);
2182 client_obd_list_lock(&cli->cl_loi_list_lock);
2186 static int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
2187 struct osc_object *osc, pdl_policy_t pol, int async)
2191 if (osc != NULL && osc_list_maint(cli, osc) == 0)
2195 /* disable osc_lru_shrink() temporarily to avoid
2196 * potential stack overrun problem. LU-2859 */
2197 atomic_inc(&cli->cl_lru_shrinkers);
2198 client_obd_list_lock(&cli->cl_loi_list_lock);
2199 osc_check_rpcs(env, cli, pol);
2200 client_obd_list_unlock(&cli->cl_loi_list_lock);
2201 atomic_dec(&cli->cl_lru_shrinkers);
2203 CDEBUG(D_CACHE, "Queue writeback work for client %p.\n", cli);
2204 LASSERT(cli->cl_writeback_work != NULL);
2205 rc = ptlrpcd_queue_work(cli->cl_writeback_work);
2210 static int osc_io_unplug_async(const struct lu_env *env,
2211 struct client_obd *cli, struct osc_object *osc)
2213 /* XXX: policy is no use actually. */
2214 return osc_io_unplug0(env, cli, osc, PDL_POLICY_ROUND, 1);
2217 void osc_io_unplug(const struct lu_env *env, struct client_obd *cli,
2218 struct osc_object *osc, pdl_policy_t pol)
2220 (void)osc_io_unplug0(env, cli, osc, pol, 0);
2223 int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
2224 struct page *page, loff_t offset)
2226 struct obd_export *exp = osc_export(osc);
2227 struct osc_async_page *oap = &ops->ops_oap;
2231 return cfs_size_round(sizeof(*oap));
2233 oap->oap_magic = OAP_MAGIC;
2234 oap->oap_cli = &exp->exp_obd->u.cli;
2237 oap->oap_page = page;
2238 oap->oap_obj_off = offset;
2239 LASSERT(!(offset & ~CFS_PAGE_MASK));
2241 if (!client_is_remote(exp) && cfs_capable(CFS_CAP_SYS_RESOURCE))
2242 oap->oap_brw_flags = OBD_BRW_NOQUOTA;
2244 INIT_LIST_HEAD(&oap->oap_pending_item);
2245 INIT_LIST_HEAD(&oap->oap_rpc_item);
2247 spin_lock_init(&oap->oap_lock);
2248 CDEBUG(D_INFO, "oap %p page %p obj off "LPU64"\n",
2249 oap, page, oap->oap_obj_off);
2253 int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
2254 struct osc_page *ops)
2256 struct osc_io *oio = osc_env_io(env);
2257 struct osc_extent *ext = NULL;
2258 struct osc_async_page *oap = &ops->ops_oap;
2259 struct client_obd *cli = oap->oap_cli;
2260 struct osc_object *osc = oap->oap_obj;
2263 int brw_flags = OBD_BRW_ASYNC;
2264 int cmd = OBD_BRW_WRITE;
2265 int need_release = 0;
2269 if (oap->oap_magic != OAP_MAGIC)
2272 if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
2275 if (!list_empty(&oap->oap_pending_item) ||
2276 !list_empty(&oap->oap_rpc_item))
2279 /* Set the OBD_BRW_SRVLOCK before the page is queued. */
2280 brw_flags |= ops->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
2281 if (!client_is_remote(osc_export(osc)) &&
2282 cfs_capable(CFS_CAP_SYS_RESOURCE)) {
2283 brw_flags |= OBD_BRW_NOQUOTA;
2284 cmd |= OBD_BRW_NOQUOTA;
2287 /* check if the file's owner/group is over quota */
2288 if (!(cmd & OBD_BRW_NOQUOTA)) {
2289 struct cl_object *obj;
2290 struct cl_attr *attr;
2291 unsigned int qid[MAXQUOTAS];
2293 obj = cl_object_top(&osc->oo_cl);
2294 attr = &osc_env_info(env)->oti_attr;
2296 cl_object_attr_lock(obj);
2297 rc = cl_object_attr_get(env, obj, attr);
2298 cl_object_attr_unlock(obj);
2300 qid[USRQUOTA] = attr->cat_uid;
2301 qid[GRPQUOTA] = attr->cat_gid;
2302 if (rc == 0 && osc_quota_chkdq(cli, qid) == NO_QUOTA)
2309 oap->oap_page_off = ops->ops_from;
2310 oap->oap_count = ops->ops_to - ops->ops_from;
2311 /* No need to hold a lock here,
2312 * since this page is not in any list yet. */
2313 oap->oap_async_flags = 0;
2314 oap->oap_brw_flags = brw_flags;
2316 OSC_IO_DEBUG(osc, "oap %p page %p added for cmd %d\n",
2317 oap, oap->oap_page, oap->oap_cmd & OBD_BRW_RWMASK);
2319 index = osc_index(oap2osc(oap));
2321 /* Add this page into extent by the following steps:
2322 * 1. if there exists an active extent for this IO, mostly this page
2323 * can be added to the active extent and sometimes we need to
2324 * expand extent to accomodate this page;
2325 * 2. otherwise, a new extent will be allocated. */
2327 ext = oio->oi_active;
2328 if (ext != NULL && ext->oe_start <= index && ext->oe_max_end >= index) {
2329 /* one chunk plus extent overhead must be enough to write this
2331 grants = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
2332 if (ext->oe_end >= index)
2335 /* it doesn't need any grant to dirty this page */
2336 client_obd_list_lock(&cli->cl_loi_list_lock);
2337 rc = osc_enter_cache_try(cli, oap, grants, 0);
2338 client_obd_list_unlock(&cli->cl_loi_list_lock);
2339 if (rc == 0) { /* try failed */
2342 } else if (ext->oe_end < index) {
2344 /* try to expand this extent */
2345 rc = osc_extent_expand(ext, index, &tmp);
2348 /* don't free reserved grant */
2350 OSC_EXTENT_DUMP(D_CACHE, ext,
2351 "expanded for %lu.\n", index);
2352 osc_unreserve_grant(cli, grants, tmp);
2357 } else if (ext != NULL) {
2358 /* index is located outside of active extent */
2362 osc_extent_release(env, ext);
2363 oio->oi_active = NULL;
2368 int tmp = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
2370 /* try to find new extent to cover this page */
2371 LASSERT(oio->oi_active == NULL);
2372 /* we may have allocated grant for this page if we failed
2373 * to expand the previous active extent. */
2374 LASSERT(ergo(grants > 0, grants >= tmp));
2378 /* we haven't allocated grant for this page. */
2379 rc = osc_enter_cache(env, cli, oap, tmp);
2386 ext = osc_extent_find(env, osc, index, &tmp);
2388 LASSERT(tmp == grants);
2389 osc_exit_cache(cli, oap);
2393 oio->oi_active = ext;
2397 osc_unreserve_grant(cli, grants, tmp);
2400 LASSERT(ergo(rc == 0, ext != NULL));
2402 EASSERTF(ext->oe_end >= index && ext->oe_start <= index,
2403 ext, "index = %lu.\n", index);
2404 LASSERT((oap->oap_brw_flags & OBD_BRW_FROM_GRANT) != 0);
2406 osc_object_lock(osc);
2407 if (ext->oe_nr_pages == 0)
2408 ext->oe_srvlock = ops->ops_srvlock;
2410 LASSERT(ext->oe_srvlock == ops->ops_srvlock);
2412 list_add_tail(&oap->oap_pending_item, &ext->oe_pages);
2413 osc_object_unlock(osc);
2418 int osc_teardown_async_page(const struct lu_env *env,
2419 struct osc_object *obj, struct osc_page *ops)
2421 struct osc_async_page *oap = &ops->ops_oap;
2422 struct osc_extent *ext = NULL;
2426 LASSERT(oap->oap_magic == OAP_MAGIC);
2428 CDEBUG(D_INFO, "teardown oap %p page %p at index %lu.\n",
2429 oap, ops, osc_index(oap2osc(oap)));
2431 osc_object_lock(obj);
2432 if (!list_empty(&oap->oap_rpc_item)) {
2433 CDEBUG(D_CACHE, "oap %p is not in cache.\n", oap);
2435 } else if (!list_empty(&oap->oap_pending_item)) {
2436 ext = osc_extent_lookup(obj, osc_index(oap2osc(oap)));
2437 /* only truncated pages are allowed to be taken out.
2438 * See osc_extent_truncate() and osc_cache_truncate_start()
2440 if (ext != NULL && ext->oe_state != OES_TRUNC) {
2441 OSC_EXTENT_DUMP(D_ERROR, ext, "trunc at %lu.\n",
2442 osc_index(oap2osc(oap)));
2446 osc_object_unlock(obj);
2448 osc_extent_put(env, ext);
2453 * This is called when a page is picked up by kernel to write out.
2455 * We should find out the corresponding extent and add the whole extent
2456 * into urgent list. The extent may be being truncated or used, handle it
2459 int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
2460 struct osc_page *ops)
2462 struct osc_extent *ext = NULL;
2463 struct osc_object *obj = cl2osc(ops->ops_cl.cpl_obj);
2464 struct cl_page *cp = ops->ops_cl.cpl_page;
2465 pgoff_t index = osc_index(ops);
2466 struct osc_async_page *oap = &ops->ops_oap;
2467 bool unplug = false;
2471 osc_object_lock(obj);
2472 ext = osc_extent_lookup(obj, index);
2474 osc_extent_tree_dump(D_ERROR, obj);
2475 LASSERTF(0, "page index %lu is NOT covered.\n", index);
2478 switch (ext->oe_state) {
2481 CL_PAGE_DEBUG(D_ERROR, env, cp, "flush an in-rpc page?\n");
2485 /* If we know this extent is being written out, we should abort
2486 * so that the writer can make this page ready. Otherwise, there
2487 * exists a deadlock problem because other process can wait for
2488 * page writeback bit holding page lock; and meanwhile in
2489 * vvp_page_make_ready(), we need to grab page lock before
2490 * really sending the RPC. */
2492 /* race with truncate, page will be redirtied */
2494 /* The extent is active so we need to abort and let the caller
2495 * re-dirty the page. If we continued on here, and we were the
2496 * one making the extent active, we could deadlock waiting for
2497 * the page writeback to clear but it won't because the extent
2498 * is active and won't be written out. */
2499 GOTO(out, rc = -EAGAIN);
2504 rc = cl_page_prep(env, io, cp, CRT_WRITE);
2508 spin_lock(&oap->oap_lock);
2509 oap->oap_async_flags |= ASYNC_READY|ASYNC_URGENT;
2510 spin_unlock(&oap->oap_lock);
2512 if (memory_pressure_get())
2513 ext->oe_memalloc = 1;
2516 if (ext->oe_state == OES_CACHE) {
2517 OSC_EXTENT_DUMP(D_CACHE, ext,
2518 "flush page %p make it urgent.\n", oap);
2519 if (list_empty(&ext->oe_link))
2520 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2527 osc_object_unlock(obj);
2528 osc_extent_put(env, ext);
2530 osc_io_unplug_async(env, osc_cli(obj), obj);
2535 * this is called when a sync waiter receives an interruption. Its job is to
2536 * get the caller woken as soon as possible. If its page hasn't been put in an
2537 * rpc yet it can dequeue immediately. Otherwise it has to mark the rpc as
2538 * desiring interruption which will forcefully complete the rpc once the rpc
2541 int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops)
2543 struct osc_async_page *oap = &ops->ops_oap;
2544 struct osc_object *obj = oap->oap_obj;
2545 struct client_obd *cli = osc_cli(obj);
2546 struct osc_extent *ext;
2547 struct osc_extent *found = NULL;
2548 struct list_head *plist;
2549 pgoff_t index = osc_index(ops);
2554 LASSERT(!oap->oap_interrupted);
2555 oap->oap_interrupted = 1;
2557 /* Find out the caching extent */
2558 osc_object_lock(obj);
2559 if (oap->oap_cmd & OBD_BRW_WRITE) {
2560 plist = &obj->oo_urgent_exts;
2561 cmd = OBD_BRW_WRITE;
2563 plist = &obj->oo_reading_exts;
2566 list_for_each_entry(ext, plist, oe_link) {
2567 if (ext->oe_start <= index && ext->oe_end >= index) {
2568 LASSERT(ext->oe_state == OES_LOCK_DONE);
2569 /* For OES_LOCK_DONE state extent, it has already held
2570 * a refcount for RPC. */
2571 found = osc_extent_get(ext);
2575 if (found != NULL) {
2576 list_del_init(&found->oe_link);
2577 osc_update_pending(obj, cmd, -found->oe_nr_pages);
2578 osc_object_unlock(obj);
2580 osc_extent_finish(env, found, 0, -EINTR);
2581 osc_extent_put(env, found);
2584 osc_object_unlock(obj);
2585 /* ok, it's been put in an rpc. only one oap gets a request
2587 if (oap->oap_request != NULL) {
2588 ptlrpc_mark_interrupted(oap->oap_request);
2589 ptlrpcd_wake(oap->oap_request);
2590 ptlrpc_req_finished(oap->oap_request);
2591 oap->oap_request = NULL;
2595 osc_list_maint(cli, obj);
2599 int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
2600 struct list_head *list, int cmd, int brw_flags)
2602 struct client_obd *cli = osc_cli(obj);
2603 struct osc_extent *ext;
2604 struct osc_async_page *oap;
2606 int mppr = cli->cl_max_pages_per_rpc;
2607 pgoff_t start = CL_PAGE_EOF;
2611 list_for_each_entry(oap, list, oap_pending_item) {
2612 pgoff_t index = osc_index(oap2osc(oap));
2618 mppr <<= (page_count > mppr);
2621 ext = osc_extent_alloc(obj);
2623 list_for_each_entry(oap, list, oap_pending_item) {
2624 list_del_init(&oap->oap_pending_item);
2625 osc_ap_completion(env, cli, oap, 0, -ENOMEM);
2630 ext->oe_rw = !!(cmd & OBD_BRW_READ);
2632 ext->oe_start = start;
2633 ext->oe_end = ext->oe_max_end = end;
2635 ext->oe_srvlock = !!(brw_flags & OBD_BRW_SRVLOCK);
2636 ext->oe_nr_pages = page_count;
2637 ext->oe_mppr = mppr;
2638 list_splice_init(list, &ext->oe_pages);
2640 osc_object_lock(obj);
2641 /* Reuse the initial refcount for RPC, don't drop it */
2642 osc_extent_state_set(ext, OES_LOCK_DONE);
2643 if (cmd & OBD_BRW_WRITE) {
2644 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2645 osc_update_pending(obj, OBD_BRW_WRITE, page_count);
2647 list_add_tail(&ext->oe_link, &obj->oo_reading_exts);
2648 osc_update_pending(obj, OBD_BRW_READ, page_count);
2650 osc_object_unlock(obj);
2652 osc_io_unplug_async(env, cli, obj);
2657 * Called by osc_io_setattr_start() to freeze and destroy covering extents.
2659 int osc_cache_truncate_start(const struct lu_env *env, struct osc_io *oio,
2660 struct osc_object *obj, __u64 size)
2662 struct client_obd *cli = osc_cli(obj);
2663 struct osc_extent *ext;
2664 struct osc_extent *waiting = NULL;
2666 struct list_head list = LIST_HEAD_INIT(list);
2671 /* pages with index greater or equal to index will be truncated. */
2672 index = cl_index(osc2cl(obj), size);
2673 partial = size > cl_offset(osc2cl(obj), index);
2676 osc_object_lock(obj);
2677 ext = osc_extent_search(obj, index);
2679 ext = first_extent(obj);
2680 else if (ext->oe_end < index)
2681 ext = next_extent(ext);
2682 while (ext != NULL) {
2683 EASSERT(ext->oe_state != OES_TRUNC, ext);
2685 if (ext->oe_state > OES_CACHE || ext->oe_urgent) {
2686 /* if ext is in urgent state, it means there must exist
2687 * a page already having been flushed by write_page().
2688 * We have to wait for this extent because we can't
2689 * truncate that page. */
2690 LASSERT(!ext->oe_hp);
2691 OSC_EXTENT_DUMP(D_CACHE, ext,
2692 "waiting for busy extent\n");
2693 waiting = osc_extent_get(ext);
2697 OSC_EXTENT_DUMP(D_CACHE, ext, "try to trunc:"LPU64".\n", size);
2699 osc_extent_get(ext);
2700 if (ext->oe_state == OES_ACTIVE) {
2701 /* though we grab inode mutex for write path, but we
2702 * release it before releasing extent(in osc_io_end()),
2703 * so there is a race window that an extent is still
2704 * in OES_ACTIVE when truncate starts. */
2705 LASSERT(!ext->oe_trunc_pending);
2706 ext->oe_trunc_pending = 1;
2708 EASSERT(ext->oe_state == OES_CACHE, ext);
2709 osc_extent_state_set(ext, OES_TRUNC);
2710 osc_update_pending(obj, OBD_BRW_WRITE,
2713 EASSERT(list_empty(&ext->oe_link), ext);
2714 list_add_tail(&ext->oe_link, &list);
2716 ext = next_extent(ext);
2718 osc_object_unlock(obj);
2720 osc_list_maint(cli, obj);
2722 while (!list_empty(&list)) {
2725 ext = list_entry(list.next, struct osc_extent, oe_link);
2726 list_del_init(&ext->oe_link);
2728 /* extent may be in OES_ACTIVE state because inode mutex
2729 * is released before osc_io_end() in file write case */
2730 if (ext->oe_state != OES_TRUNC)
2731 osc_extent_wait(env, ext, OES_TRUNC);
2733 rc = osc_extent_truncate(ext, index, partial);
2738 OSC_EXTENT_DUMP(D_ERROR, ext,
2739 "truncate error %d\n", rc);
2740 } else if (ext->oe_nr_pages == 0) {
2741 osc_extent_remove(ext);
2743 /* this must be an overlapped extent which means only
2744 * part of pages in this extent have been truncated.
2746 EASSERTF(ext->oe_start <= index, ext,
2747 "trunc index = %lu/%d.\n", index, partial);
2748 /* fix index to skip this partially truncated extent */
2749 index = ext->oe_end + 1;
2752 /* we need to hold this extent in OES_TRUNC state so
2753 * that no writeback will happen. This is to avoid
2755 LASSERT(oio->oi_trunc == NULL);
2756 oio->oi_trunc = osc_extent_get(ext);
2757 OSC_EXTENT_DUMP(D_CACHE, ext,
2758 "trunc at "LPU64"\n", size);
2760 osc_extent_put(env, ext);
2762 if (waiting != NULL) {
2765 /* ignore the result of osc_extent_wait the write initiator
2766 * should take care of it. */
2767 rc = osc_extent_wait(env, waiting, OES_INV);
2769 OSC_EXTENT_DUMP(D_CACHE, waiting, "error: %d.\n", rc);
2771 osc_extent_put(env, waiting);
2779 * Called after osc_io_setattr_end to add oio->oi_trunc back to cache.
2781 void osc_cache_truncate_end(const struct lu_env *env, struct osc_io *oio,
2782 struct osc_object *obj)
2784 struct osc_extent *ext = oio->oi_trunc;
2786 oio->oi_trunc = NULL;
2788 bool unplug = false;
2790 EASSERT(ext->oe_nr_pages > 0, ext);
2791 EASSERT(ext->oe_state == OES_TRUNC, ext);
2792 EASSERT(!ext->oe_urgent, ext);
2794 OSC_EXTENT_DUMP(D_CACHE, ext, "trunc -> cache.\n");
2795 osc_object_lock(obj);
2796 osc_extent_state_set(ext, OES_CACHE);
2797 if (ext->oe_fsync_wait && !ext->oe_urgent) {
2799 list_move_tail(&ext->oe_link, &obj->oo_urgent_exts);
2802 osc_update_pending(obj, OBD_BRW_WRITE, ext->oe_nr_pages);
2803 osc_object_unlock(obj);
2804 osc_extent_put(env, ext);
2807 osc_io_unplug_async(env, osc_cli(obj), obj);
2812 * Wait for extents in a specific range to be written out.
2813 * The caller must have called osc_cache_writeback_range() to issue IO
2814 * otherwise it will take a long time for this function to finish.
2816 * Caller must hold inode_mutex , or cancel exclusive dlm lock so that
2817 * nobody else can dirty this range of file while we're waiting for
2818 * extents to be written.
2820 int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
2821 pgoff_t start, pgoff_t end)
2823 struct osc_extent *ext;
2824 pgoff_t index = start;
2829 osc_object_lock(obj);
2830 ext = osc_extent_search(obj, index);
2832 ext = first_extent(obj);
2833 else if (ext->oe_end < index)
2834 ext = next_extent(ext);
2835 while (ext != NULL) {
2838 if (ext->oe_start > end)
2841 if (!ext->oe_fsync_wait) {
2842 ext = next_extent(ext);
2846 EASSERT(ergo(ext->oe_state == OES_CACHE,
2847 ext->oe_hp || ext->oe_urgent), ext);
2848 EASSERT(ergo(ext->oe_state == OES_ACTIVE,
2849 !ext->oe_hp && ext->oe_urgent), ext);
2851 index = ext->oe_end + 1;
2852 osc_extent_get(ext);
2853 osc_object_unlock(obj);
2855 rc = osc_extent_wait(env, ext, OES_INV);
2858 osc_extent_put(env, ext);
2861 osc_object_unlock(obj);
2863 OSC_IO_DEBUG(obj, "sync file range.\n");
2868 * Called to write out a range of osc object.
2870 * @hp : should be set this is caused by lock cancel;
2871 * @discard: is set if dirty pages should be dropped - file will be deleted or
2872 * truncated, this implies there is no partially discarding extents.
2874 * Return how many pages will be issued, or error code if error occurred.
2876 int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
2877 pgoff_t start, pgoff_t end, int hp, int discard)
2879 struct osc_extent *ext;
2880 struct list_head discard_list = LIST_HEAD_INIT(discard_list);
2881 bool unplug = false;
2885 osc_object_lock(obj);
2886 ext = osc_extent_search(obj, start);
2888 ext = first_extent(obj);
2889 else if (ext->oe_end < start)
2890 ext = next_extent(ext);
2891 while (ext != NULL) {
2892 if (ext->oe_start > end)
2895 ext->oe_fsync_wait = 1;
2896 switch (ext->oe_state) {
2898 result += ext->oe_nr_pages;
2900 struct list_head *list = NULL;
2902 EASSERT(!ext->oe_hp, ext);
2904 list = &obj->oo_hp_exts;
2905 } else if (!ext->oe_urgent) {
2907 list = &obj->oo_urgent_exts;
2910 list_move_tail(&ext->oe_link, list);
2913 /* the only discarder is lock cancelling, so
2914 * [start, end] must contain this extent */
2915 EASSERT(ext->oe_start >= start &&
2916 ext->oe_max_end <= end, ext);
2917 osc_extent_state_set(ext, OES_LOCKING);
2918 ext->oe_owner = current;
2919 list_move_tail(&ext->oe_link,
2921 osc_update_pending(obj, OBD_BRW_WRITE,
2926 /* It's pretty bad to wait for ACTIVE extents, because
2927 * we don't know how long we will wait for it to be
2928 * flushed since it may be blocked at awaiting more
2929 * grants. We do this for the correctness of fsync. */
2930 LASSERT(hp == 0 && discard == 0);
2934 /* this extent is being truncated, can't do anything
2935 * for it now. it will be set to urgent after truncate
2936 * is finished in osc_cache_truncate_end(). */
2940 ext = next_extent(ext);
2942 osc_object_unlock(obj);
2944 LASSERT(ergo(!discard, list_empty(&discard_list)));
2945 if (!list_empty(&discard_list)) {
2946 struct osc_extent *tmp;
2949 osc_list_maint(osc_cli(obj), obj);
2950 list_for_each_entry_safe(ext, tmp, &discard_list, oe_link) {
2951 list_del_init(&ext->oe_link);
2952 EASSERT(ext->oe_state == OES_LOCKING, ext);
2954 /* Discard caching pages. We don't actually write this
2955 * extent out but we complete it as if we did. */
2956 rc = osc_extent_make_ready(env, ext);
2957 if (unlikely(rc < 0)) {
2958 OSC_EXTENT_DUMP(D_ERROR, ext,
2959 "make_ready returned %d\n", rc);
2964 /* finish the extent as if the pages were sent */
2965 osc_extent_finish(env, ext, 0, 0);
2970 osc_io_unplug(env, osc_cli(obj), obj, PDL_POLICY_ROUND);
2972 if (hp || discard) {
2974 rc = osc_cache_wait_range(env, obj, start, end);
2975 if (result >= 0 && rc < 0)
2979 OSC_IO_DEBUG(obj, "pageout [%lu, %lu], %d.\n", start, end, result);
2984 * Returns a list of pages by a given [start, end] of \a obj.
2986 * \param resched If not NULL, then we give up before hogging CPU for too
2987 * long and set *resched = 1, in that case caller should implement a retry
2990 * Gang tree lookup (radix_tree_gang_lookup()) optimization is absolutely
2991 * crucial in the face of [offset, EOF] locks.
2993 * Return at least one page in @queue unless there is no covered page.
2995 int osc_page_gang_lookup(const struct lu_env *env, struct cl_io *io,
2996 struct osc_object *osc, pgoff_t start, pgoff_t end,
2997 osc_page_gang_cbt cb, void *cbdata)
2999 struct osc_page *ops;
3005 int res = CLP_GANG_OKAY;
3006 bool tree_lock = true;
3010 pvec = osc_env_info(env)->oti_pvec;
3011 spin_lock(&osc->oo_tree_lock);
3012 while ((nr = radix_tree_gang_lookup(&osc->oo_tree, pvec,
3013 idx, OTI_PVEC_SIZE)) > 0) {
3014 struct cl_page *page;
3015 bool end_of_region = false;
3017 for (i = 0, j = 0; i < nr; ++i) {
3021 idx = osc_index(ops);
3023 end_of_region = true;
3027 page = ops->ops_cl.cpl_page;
3028 LASSERT(page->cp_type == CPT_CACHEABLE);
3029 if (page->cp_state == CPS_FREEING)
3033 lu_ref_add_atomic(&page->cp_reference,
3034 "gang_lookup", current);
3040 * Here a delicate locking dance is performed. Current thread
3041 * holds a reference to a page, but has to own it before it
3042 * can be placed into queue. Owning implies waiting, so
3043 * radix-tree lock is to be released. After a wait one has to
3044 * check that pages weren't truncated (cl_page_own() returns
3045 * error in the latter case).
3047 spin_unlock(&osc->oo_tree_lock);
3050 for (i = 0; i < j; ++i) {
3052 if (res == CLP_GANG_OKAY)
3053 res = (*cb)(env, io, ops, cbdata);
3055 page = ops->ops_cl.cpl_page;
3056 lu_ref_del(&page->cp_reference, "gang_lookup", current);
3057 cl_page_put(env, page);
3059 if (nr < OTI_PVEC_SIZE || end_of_region)
3062 if (res == CLP_GANG_OKAY && need_resched())
3063 res = CLP_GANG_RESCHED;
3064 if (res != CLP_GANG_OKAY)
3067 spin_lock(&osc->oo_tree_lock);
3071 spin_unlock(&osc->oo_tree_lock);
3076 * Check if page @page is covered by an extra lock or discard it.
3078 static int check_and_discard_cb(const struct lu_env *env, struct cl_io *io,
3079 struct osc_page *ops, void *cbdata)
3081 struct osc_thread_info *info = osc_env_info(env);
3082 struct cl_lock *lock = cbdata;
3085 index = osc_index(ops);
3086 if (index >= info->oti_fn_index) {
3087 struct cl_lock *tmp;
3088 struct cl_page *page = ops->ops_cl.cpl_page;
3090 /* refresh non-overlapped index */
3091 tmp = cl_lock_at_pgoff(env, lock->cll_descr.cld_obj, index,
3094 /* Cache the first-non-overlapped index so as to skip
3095 * all pages within [index, oti_fn_index). This
3096 * is safe because if tmp lock is canceled, it will
3097 * discard these pages. */
3098 info->oti_fn_index = tmp->cll_descr.cld_end + 1;
3099 if (tmp->cll_descr.cld_end == CL_PAGE_EOF)
3100 info->oti_fn_index = CL_PAGE_EOF;
3101 cl_lock_put(env, tmp);
3102 } else if (cl_page_own(env, io, page) == 0) {
3103 /* discard the page */
3104 cl_page_discard(env, io, page);
3105 cl_page_disown(env, io, page);
3107 LASSERT(page->cp_state == CPS_FREEING);
3111 info->oti_next_index = index + 1;
3112 return CLP_GANG_OKAY;
3115 static int discard_cb(const struct lu_env *env, struct cl_io *io,
3116 struct osc_page *ops, void *cbdata)
3118 struct osc_thread_info *info = osc_env_info(env);
3119 struct cl_lock *lock = cbdata;
3120 struct cl_page *page = ops->ops_cl.cpl_page;
3122 LASSERT(lock->cll_descr.cld_mode >= CLM_WRITE);
3124 /* page is top page. */
3125 info->oti_next_index = osc_index(ops) + 1;
3126 if (cl_page_own(env, io, page) == 0) {
3127 KLASSERT(ergo(page->cp_type == CPT_CACHEABLE,
3128 !PageDirty(cl_page_vmpage(page))));
3130 /* discard the page */
3131 cl_page_discard(env, io, page);
3132 cl_page_disown(env, io, page);
3134 LASSERT(page->cp_state == CPS_FREEING);
3137 return CLP_GANG_OKAY;
3141 * Discard pages protected by the given lock. This function traverses radix
3142 * tree to find all covering pages and discard them. If a page is being covered
3143 * by other locks, it should remain in cache.
3145 * If error happens on any step, the process continues anyway (the reasoning
3146 * behind this being that lock cancellation cannot be delayed indefinitely).
3148 int osc_lock_discard_pages(const struct lu_env *env, struct osc_lock *ols)
3150 struct osc_thread_info *info = osc_env_info(env);
3151 struct cl_io *io = &info->oti_io;
3152 struct cl_object *osc = ols->ols_cl.cls_obj;
3153 struct cl_lock *lock = ols->ols_cl.cls_lock;
3154 struct cl_lock_descr *descr = &lock->cll_descr;
3155 osc_page_gang_cbt cb;
3161 io->ci_obj = cl_object_top(osc);
3162 io->ci_ignore_layout = 1;
3163 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
3167 cb = descr->cld_mode == CLM_READ ? check_and_discard_cb : discard_cb;
3168 info->oti_fn_index = info->oti_next_index = descr->cld_start;
3170 res = osc_page_gang_lookup(env, io, cl2osc(osc),
3171 info->oti_next_index, descr->cld_end,
3173 if (info->oti_next_index > descr->cld_end)
3176 if (res == CLP_GANG_RESCHED)
3178 } while (res != CLP_GANG_OKAY);
3180 cl_io_fini(env, io);