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, 2015, Intel Corporation.
34 * This file is part of Lustre, http://www.lustre.org/
35 * Lustre is a trademark of Sun Microsystems, Inc.
37 * osc cache management.
39 * Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
42 #define DEBUG_SUBSYSTEM S_OSC
44 #include "osc_cl_internal.h"
45 #include "osc_internal.h"
47 static int extent_debug; /* set it to be true for more debug */
49 static void osc_update_pending(struct osc_object *obj, int cmd, int delta);
50 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
51 enum osc_extent_state state);
52 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
53 struct osc_async_page *oap, int sent, int rc);
54 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
56 static int osc_refresh_count(const struct lu_env *env,
57 struct osc_async_page *oap, int cmd);
58 static int osc_io_unplug_async(const struct lu_env *env,
59 struct client_obd *cli, struct osc_object *osc);
60 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
61 unsigned int lost_grant, unsigned int dirty_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__)
68 static void osc_unreserve_grant(struct client_obd *cli, unsigned int reserved,
75 /* ------------------ osc extent ------------------ */
76 static inline char *ext_flags(struct osc_extent *ext, char *flags)
79 *buf++ = ext->oe_rw ? 'r' : 'w';
92 if (ext->oe_trunc_pending)
94 if (ext->oe_fsync_wait)
100 static inline char list_empty_marker(struct list_head *list)
102 return list_empty(list) ? '-' : '+';
105 #define EXTSTR "[%lu -> %lu/%lu]"
106 #define EXTPARA(ext) (ext)->oe_start, (ext)->oe_end, (ext)->oe_max_end
107 static const char *oes_strings[] = {
108 "inv", "active", "cache", "locking", "lockdone", "rpc", "trunc", NULL };
110 #define OSC_EXTENT_DUMP(lvl, extent, fmt, ...) do { \
111 struct osc_extent *__ext = (extent); \
115 "extent %p@{" EXTSTR ", " \
116 "[%d|%d|%c|%s|%s|%p], [%d|%d|%c|%c|%p|%u|%p]} " fmt, \
117 /* ----- extent part 0 ----- */ \
118 __ext, EXTPARA(__ext), \
119 /* ----- part 1 ----- */ \
120 atomic_read(&__ext->oe_refc), \
121 atomic_read(&__ext->oe_users), \
122 list_empty_marker(&__ext->oe_link), \
123 oes_strings[__ext->oe_state], ext_flags(__ext, __buf), \
125 /* ----- part 2 ----- */ \
126 __ext->oe_grants, __ext->oe_nr_pages, \
127 list_empty_marker(&__ext->oe_pages), \
128 waitqueue_active(&__ext->oe_waitq) ? '+' : '-', \
129 __ext->oe_dlmlock, __ext->oe_mppr, __ext->oe_owner, \
130 /* ----- part 4 ----- */ \
132 if (lvl == D_ERROR && __ext->oe_dlmlock != NULL) \
133 LDLM_ERROR(__ext->oe_dlmlock, "extent: %p\n", __ext); \
135 LDLM_DEBUG(__ext->oe_dlmlock, "extent: %p\n", __ext); \
139 #define EASSERTF(expr, ext, fmt, args...) do { \
141 OSC_EXTENT_DUMP(D_ERROR, (ext), fmt, ##args); \
142 osc_extent_tree_dump(D_ERROR, (ext)->oe_obj); \
148 #define EASSERT(expr, ext) EASSERTF(expr, ext, "\n")
150 static inline struct osc_extent *rb_extent(struct rb_node *n)
155 return container_of(n, struct osc_extent, oe_node);
158 static inline struct osc_extent *next_extent(struct osc_extent *ext)
163 LASSERT(ext->oe_intree);
164 return rb_extent(rb_next(&ext->oe_node));
167 static inline struct osc_extent *prev_extent(struct osc_extent *ext)
172 LASSERT(ext->oe_intree);
173 return rb_extent(rb_prev(&ext->oe_node));
176 static inline struct osc_extent *first_extent(struct osc_object *obj)
178 return rb_extent(rb_first(&obj->oo_root));
181 /* object must be locked by caller. */
182 static int osc_extent_sanity_check0(struct osc_extent *ext,
183 const char *func, const int line)
185 struct osc_object *obj = ext->oe_obj;
186 struct osc_async_page *oap;
190 if (!osc_object_is_locked(obj))
193 if (ext->oe_state >= OES_STATE_MAX)
196 if (atomic_read(&ext->oe_refc) <= 0)
199 if (atomic_read(&ext->oe_refc) < atomic_read(&ext->oe_users))
202 switch (ext->oe_state) {
204 if (ext->oe_nr_pages > 0 || !list_empty(&ext->oe_pages))
209 if (atomic_read(&ext->oe_users) == 0)
213 if (ext->oe_fsync_wait && !ext->oe_urgent)
217 if (ext->oe_grants == 0)
219 if (ext->oe_fsync_wait && !ext->oe_urgent && !ext->oe_hp)
222 if (atomic_read(&ext->oe_users) > 0)
226 if (ext->oe_max_end < ext->oe_end || ext->oe_end < ext->oe_start)
229 if (ext->oe_sync && ext->oe_grants > 0)
232 if (ext->oe_dlmlock != NULL && !ldlm_is_failed(ext->oe_dlmlock)) {
233 struct ldlm_extent *extent;
235 extent = &ext->oe_dlmlock->l_policy_data.l_extent;
236 if (!(extent->start <= cl_offset(osc2cl(obj), ext->oe_start) &&
237 extent->end >= cl_offset(osc2cl(obj), ext->oe_max_end)))
240 if (!(ext->oe_dlmlock->l_granted_mode & (LCK_PW | LCK_GROUP)))
244 if (ext->oe_nr_pages > ext->oe_mppr)
247 /* Do not verify page list if extent is in RPC. This is because an
248 * in-RPC extent is supposed to be exclusively accessible w/o lock. */
249 if (ext->oe_state > OES_CACHE)
256 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
257 pgoff_t index = osc_index(oap2osc(oap));
259 if (index > ext->oe_end || index < ext->oe_start)
262 if (page_count != ext->oe_nr_pages)
267 OSC_EXTENT_DUMP(D_ERROR, ext,
268 "%s:%d sanity check %p failed with rc = %d\n",
269 func, line, ext, rc);
273 #define sanity_check_nolock(ext) \
274 osc_extent_sanity_check0(ext, __func__, __LINE__)
276 #define sanity_check(ext) ({ \
278 osc_object_lock((ext)->oe_obj); \
279 __res = sanity_check_nolock(ext); \
280 osc_object_unlock((ext)->oe_obj); \
286 * sanity check - to make sure there is no overlapped extent in the tree.
288 static int osc_extent_is_overlapped(struct osc_object *obj,
289 struct osc_extent *ext)
291 struct osc_extent *tmp;
293 LASSERT(osc_object_is_locked(obj));
298 for (tmp = first_extent(obj); tmp != NULL; tmp = next_extent(tmp)) {
301 if (tmp->oe_end >= ext->oe_start &&
302 tmp->oe_start <= ext->oe_end)
308 static void osc_extent_state_set(struct osc_extent *ext, int state)
310 LASSERT(osc_object_is_locked(ext->oe_obj));
311 LASSERT(state >= OES_INV && state < OES_STATE_MAX);
313 /* Never try to sanity check a state changing extent :-) */
314 /* LASSERT(sanity_check_nolock(ext) == 0); */
316 /* TODO: validate the state machine */
317 ext->oe_state = state;
318 wake_up_all(&ext->oe_waitq);
321 static struct osc_extent *osc_extent_alloc(struct osc_object *obj)
323 struct osc_extent *ext;
325 OBD_SLAB_ALLOC_PTR_GFP(ext, osc_extent_kmem, GFP_IOFS);
329 RB_CLEAR_NODE(&ext->oe_node);
331 cl_object_get(osc2cl(obj));
332 atomic_set(&ext->oe_refc, 1);
333 atomic_set(&ext->oe_users, 0);
334 INIT_LIST_HEAD(&ext->oe_link);
335 ext->oe_state = OES_INV;
336 INIT_LIST_HEAD(&ext->oe_pages);
337 init_waitqueue_head(&ext->oe_waitq);
338 ext->oe_dlmlock = NULL;
343 static void osc_extent_free(struct osc_extent *ext)
345 OBD_SLAB_FREE_PTR(ext, osc_extent_kmem);
348 static struct osc_extent *osc_extent_get(struct osc_extent *ext)
350 LASSERT(atomic_read(&ext->oe_refc) >= 0);
351 atomic_inc(&ext->oe_refc);
355 static void osc_extent_put(const struct lu_env *env, struct osc_extent *ext)
357 LASSERT(atomic_read(&ext->oe_refc) > 0);
358 if (atomic_dec_and_test(&ext->oe_refc)) {
359 LASSERT(list_empty(&ext->oe_link));
360 LASSERT(atomic_read(&ext->oe_users) == 0);
361 LASSERT(ext->oe_state == OES_INV);
362 LASSERT(!ext->oe_intree);
364 if (ext->oe_dlmlock != NULL) {
365 lu_ref_add(&ext->oe_dlmlock->l_reference,
367 LDLM_LOCK_PUT(ext->oe_dlmlock);
368 ext->oe_dlmlock = NULL;
370 cl_object_put(env, osc2cl(ext->oe_obj));
371 osc_extent_free(ext);
376 * osc_extent_put_trust() is a special version of osc_extent_put() when
377 * it's known that the caller is not the last user. This is to address the
378 * problem of lacking of lu_env ;-).
380 static void osc_extent_put_trust(struct osc_extent *ext)
382 LASSERT(atomic_read(&ext->oe_refc) > 1);
383 LASSERT(osc_object_is_locked(ext->oe_obj));
384 atomic_dec(&ext->oe_refc);
388 * Return the extent which includes pgoff @index, or return the greatest
389 * previous extent in the tree.
391 static struct osc_extent *osc_extent_search(struct osc_object *obj,
394 struct rb_node *n = obj->oo_root.rb_node;
395 struct osc_extent *tmp, *p = NULL;
397 LASSERT(osc_object_is_locked(obj));
400 if (index < tmp->oe_start) {
402 } else if (index > tmp->oe_end) {
413 * Return the extent covering @index, otherwise return NULL.
414 * caller must have held object lock.
416 static struct osc_extent *osc_extent_lookup(struct osc_object *obj,
419 struct osc_extent *ext;
421 ext = osc_extent_search(obj, index);
422 if (ext != NULL && ext->oe_start <= index && index <= ext->oe_end)
423 return osc_extent_get(ext);
427 /* caller must have held object lock. */
428 static void osc_extent_insert(struct osc_object *obj, struct osc_extent *ext)
430 struct rb_node **n = &obj->oo_root.rb_node;
431 struct rb_node *parent = NULL;
432 struct osc_extent *tmp;
434 LASSERT(ext->oe_intree == 0);
435 LASSERT(ext->oe_obj == obj);
436 LASSERT(osc_object_is_locked(obj));
441 if (ext->oe_end < tmp->oe_start)
443 else if (ext->oe_start > tmp->oe_end)
446 EASSERTF(0, tmp, EXTSTR"\n", EXTPARA(ext));
448 rb_link_node(&ext->oe_node, parent, n);
449 rb_insert_color(&ext->oe_node, &obj->oo_root);
454 /* caller must have held object lock. */
455 static void osc_extent_erase(struct osc_extent *ext)
457 struct osc_object *obj = ext->oe_obj;
458 LASSERT(osc_object_is_locked(obj));
459 if (ext->oe_intree) {
460 rb_erase(&ext->oe_node, &obj->oo_root);
462 /* rbtree held a refcount */
463 osc_extent_put_trust(ext);
467 static struct osc_extent *osc_extent_hold(struct osc_extent *ext)
469 struct osc_object *obj = ext->oe_obj;
471 LASSERT(osc_object_is_locked(obj));
472 LASSERT(ext->oe_state == OES_ACTIVE || ext->oe_state == OES_CACHE);
473 if (ext->oe_state == OES_CACHE) {
474 osc_extent_state_set(ext, OES_ACTIVE);
475 osc_update_pending(obj, OBD_BRW_WRITE, -ext->oe_nr_pages);
477 atomic_inc(&ext->oe_users);
478 list_del_init(&ext->oe_link);
479 return osc_extent_get(ext);
482 static void __osc_extent_remove(struct osc_extent *ext)
484 LASSERT(osc_object_is_locked(ext->oe_obj));
485 LASSERT(list_empty(&ext->oe_pages));
486 osc_extent_erase(ext);
487 list_del_init(&ext->oe_link);
488 osc_extent_state_set(ext, OES_INV);
489 OSC_EXTENT_DUMP(D_CACHE, ext, "destroyed.\n");
492 static void osc_extent_remove(struct osc_extent *ext)
494 struct osc_object *obj = ext->oe_obj;
496 osc_object_lock(obj);
497 __osc_extent_remove(ext);
498 osc_object_unlock(obj);
502 * This function is used to merge extents to get better performance. It checks
503 * if @cur and @victim are contiguous at block level.
505 static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
506 struct osc_extent *victim)
508 struct osc_object *obj = cur->oe_obj;
509 struct client_obd *cli = osc_cli(obj);
514 LASSERT(cur->oe_state == OES_CACHE);
515 LASSERT(osc_object_is_locked(obj));
519 if (victim->oe_state != OES_CACHE || victim->oe_fsync_wait)
522 if (cur->oe_max_end != victim->oe_max_end)
525 LASSERT(cur->oe_dlmlock == victim->oe_dlmlock);
526 ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_CACHE_SHIFT;
527 chunk_start = cur->oe_start >> ppc_bits;
528 chunk_end = cur->oe_end >> ppc_bits;
529 if (chunk_start != (victim->oe_end >> ppc_bits) + 1 &&
530 chunk_end + 1 != victim->oe_start >> ppc_bits)
533 /* overall extent size should not exceed the max supported limit
534 * reported by the server */
535 if (cur->oe_end - cur->oe_start + 1 +
536 victim->oe_end - victim->oe_start + 1 > cli->cl_max_extent_pages)
539 OSC_EXTENT_DUMP(D_CACHE, victim, "will be merged by %p.\n", cur);
541 cur->oe_start = min(cur->oe_start, victim->oe_start);
542 cur->oe_end = max(cur->oe_end, victim->oe_end);
543 /* per-extent tax should be accounted only once for the whole extent */
544 cur->oe_grants += victim->oe_grants - cli->cl_grant_extent_tax;
545 cur->oe_nr_pages += victim->oe_nr_pages;
546 /* only the following bits are needed to merge */
547 cur->oe_urgent |= victim->oe_urgent;
548 cur->oe_memalloc |= victim->oe_memalloc;
549 list_splice_init(&victim->oe_pages, &cur->oe_pages);
550 list_del_init(&victim->oe_link);
551 victim->oe_nr_pages = 0;
553 osc_extent_get(victim);
554 __osc_extent_remove(victim);
555 osc_extent_put(env, victim);
557 OSC_EXTENT_DUMP(D_CACHE, cur, "after merging %p.\n", victim);
562 * Drop user count of osc_extent, and unplug IO asynchronously.
564 int osc_extent_release(const struct lu_env *env, struct osc_extent *ext)
566 struct osc_object *obj = ext->oe_obj;
567 struct client_obd *cli = osc_cli(obj);
571 LASSERT(atomic_read(&ext->oe_users) > 0);
572 LASSERT(sanity_check(ext) == 0);
573 LASSERT(ext->oe_grants > 0);
575 if (atomic_dec_and_lock(&ext->oe_users, &obj->oo_lock)) {
576 LASSERT(ext->oe_state == OES_ACTIVE);
577 if (ext->oe_trunc_pending) {
578 /* a truncate process is waiting for this extent.
579 * This may happen due to a race, check
580 * osc_cache_truncate_start(). */
581 osc_extent_state_set(ext, OES_TRUNC);
582 ext->oe_trunc_pending = 0;
586 osc_extent_state_set(ext, OES_CACHE);
587 osc_update_pending(obj, OBD_BRW_WRITE,
590 /* try to merge the previous and next extent. */
591 if (osc_extent_merge(env, ext, prev_extent(ext)) == 0)
592 grant += cli->cl_grant_extent_tax;
593 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
594 grant += cli->cl_grant_extent_tax;
596 osc_unreserve_grant(cli, 0, grant);
599 list_move_tail(&ext->oe_link,
600 &obj->oo_urgent_exts);
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 LASSERT(cli->cl_chunkbits >= PAGE_CACHE_SHIFT);
651 ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
652 chunk_mask = ~((1 << ppc_bits) - 1);
653 chunksize = 1 << cli->cl_chunkbits;
654 chunk = index >> ppc_bits;
656 /* align end to rpc edge, rpc size may not be a power 2 integer. */
657 max_pages = cli->cl_max_pages_per_rpc;
658 LASSERT((max_pages & ~chunk_mask) == 0);
659 max_end = index - (index % max_pages) + max_pages - 1;
660 max_end = min_t(pgoff_t, max_end, descr->cld_end);
662 /* initialize new extent by parameters so far */
663 cur->oe_max_end = max_end;
664 cur->oe_start = index & chunk_mask;
665 cur->oe_end = ((index + ~chunk_mask + 1) & chunk_mask) - 1;
666 if (cur->oe_start < descr->cld_start)
667 cur->oe_start = descr->cld_start;
668 if (cur->oe_end > max_end)
669 cur->oe_end = max_end;
671 cur->oe_mppr = max_pages;
672 if (olck->ols_dlmlock != NULL) {
673 LASSERT(olck->ols_hold);
674 cur->oe_dlmlock = LDLM_LOCK_GET(olck->ols_dlmlock);
675 lu_ref_add(&olck->ols_dlmlock->l_reference, "osc_extent", cur);
678 /* grants has been allocated by caller */
679 LASSERTF(*grants >= chunksize + cli->cl_grant_extent_tax,
680 "%u/%u/%u.\n", *grants, chunksize, cli->cl_grant_extent_tax);
681 LASSERTF((max_end - cur->oe_start) < max_pages, EXTSTR"\n",
685 osc_object_lock(obj);
686 ext = osc_extent_search(obj, cur->oe_start);
688 ext = first_extent(obj);
689 while (ext != NULL) {
690 pgoff_t ext_chk_start = ext->oe_start >> ppc_bits;
691 pgoff_t ext_chk_end = ext->oe_end >> ppc_bits;
693 LASSERT(sanity_check_nolock(ext) == 0);
694 if (chunk > ext_chk_end + 1)
697 /* if covering by different locks, no chance to match */
698 if (olck->ols_dlmlock != ext->oe_dlmlock) {
699 EASSERTF(!overlapped(ext, cur), ext,
700 EXTSTR"\n", EXTPARA(cur));
702 ext = next_extent(ext);
706 /* discontiguous chunks? */
707 if (chunk + 1 < ext_chk_start) {
708 ext = next_extent(ext);
712 /* ok, from now on, ext and cur have these attrs:
713 * 1. covered by the same lock
714 * 2. contiguous at chunk level or overlapping. */
716 if (overlapped(ext, cur)) {
717 /* cur is the minimum unit, so overlapping means
719 EASSERTF((ext->oe_start <= cur->oe_start &&
720 ext->oe_end >= cur->oe_end),
721 ext, EXTSTR"\n", EXTPARA(cur));
723 if (ext->oe_state > OES_CACHE || ext->oe_fsync_wait) {
724 /* for simplicity, we wait for this extent to
725 * finish before going forward. */
726 conflict = osc_extent_get(ext);
730 found = osc_extent_hold(ext);
734 /* non-overlapped extent */
735 if (ext->oe_state != OES_CACHE || ext->oe_fsync_wait) {
736 /* we can't do anything for a non OES_CACHE extent, or
737 * if there is someone waiting for this extent to be
738 * flushed, try next one. */
739 ext = next_extent(ext);
743 /* check if they belong to the same rpc slot before trying to
744 * merge. the extents are not overlapped and contiguous at
745 * chunk level to get here. */
746 if (ext->oe_max_end != max_end) {
747 /* if they don't belong to the same RPC slot or
748 * max_pages_per_rpc has ever changed, do not merge. */
749 ext = next_extent(ext);
753 /* check whether maximum extent size will be hit */
754 if ((ext_chk_end - ext_chk_start + 1 + 1) << ppc_bits >
755 cli->cl_max_extent_pages) {
756 ext = next_extent(ext);
760 /* it's required that an extent must be contiguous at chunk
761 * level so that we know the whole extent is covered by grant
762 * (the pages in the extent are NOT required to be contiguous).
763 * Otherwise, it will be too much difficult to know which
764 * chunks have grants allocated. */
766 /* try to do front merge - extend ext's start */
767 if (chunk + 1 == ext_chk_start) {
768 /* ext must be chunk size aligned */
769 EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
771 /* pull ext's start back to cover cur */
772 ext->oe_start = cur->oe_start;
773 ext->oe_grants += chunksize;
774 *grants -= chunksize;
776 found = osc_extent_hold(ext);
777 } else if (chunk == ext_chk_end + 1) {
779 ext->oe_end = cur->oe_end;
780 ext->oe_grants += chunksize;
781 *grants -= chunksize;
783 /* try to merge with the next one because we just fill
785 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
786 /* we can save extent tax from next extent */
787 *grants += cli->cl_grant_extent_tax;
789 found = osc_extent_hold(ext);
794 ext = next_extent(ext);
797 osc_extent_tree_dump(D_CACHE, obj);
799 LASSERT(conflict == NULL);
800 if (!IS_ERR(found)) {
801 LASSERT(found->oe_dlmlock == cur->oe_dlmlock);
802 OSC_EXTENT_DUMP(D_CACHE, found,
803 "found caching ext for %lu.\n", index);
805 } else if (conflict == NULL) {
806 /* create a new extent */
807 EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
808 cur->oe_grants = chunksize + cli->cl_grant_extent_tax;
809 *grants -= cur->oe_grants;
810 LASSERT(*grants >= 0);
812 cur->oe_state = OES_CACHE;
813 found = osc_extent_hold(cur);
814 osc_extent_insert(obj, cur);
815 OSC_EXTENT_DUMP(D_CACHE, cur, "add into tree %lu/%lu.\n",
816 index, descr->cld_end);
818 osc_object_unlock(obj);
820 if (conflict != NULL) {
821 LASSERT(found == NULL);
823 /* waiting for IO to finish. Please notice that it's impossible
824 * to be an OES_TRUNC extent. */
825 rc = osc_extent_wait(env, conflict, OES_INV);
826 osc_extent_put(env, conflict);
829 GOTO(out, found = ERR_PTR(rc));
836 osc_extent_put(env, cur);
837 LASSERT(*grants >= 0);
842 * Called when IO is finished to an extent.
844 int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
847 struct client_obd *cli = osc_cli(ext->oe_obj);
848 struct osc_async_page *oap;
849 struct osc_async_page *tmp;
850 int nr_pages = ext->oe_nr_pages;
852 int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
857 OSC_EXTENT_DUMP(D_CACHE, ext, "extent finished.\n");
859 ext->oe_rc = rc ?: ext->oe_nr_pages;
860 EASSERT(ergo(rc == 0, ext->oe_state == OES_RPC), ext);
862 osc_lru_add_batch(cli, &ext->oe_pages);
863 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
865 list_del_init(&oap->oap_rpc_item);
866 list_del_init(&oap->oap_pending_item);
867 if (last_off <= oap->oap_obj_off) {
868 last_off = oap->oap_obj_off;
869 last_count = oap->oap_count;
873 osc_ap_completion(env, cli, oap, sent, rc);
875 EASSERT(ext->oe_nr_pages == 0, ext);
878 lost_grant = ext->oe_grants;
879 } else if (blocksize < PAGE_CACHE_SIZE &&
880 last_count != PAGE_CACHE_SIZE) {
881 /* For short writes we shouldn't count parts of pages that
882 * span a whole chunk on the OST side, or our accounting goes
883 * wrong. Should match the code in filter_grant_check. */
884 int offset = last_off & ~PAGE_MASK;
885 int count = last_count + (offset & (blocksize - 1));
886 int end = (offset + last_count) & (blocksize - 1);
888 count += blocksize - end;
890 lost_grant = PAGE_CACHE_SIZE - count;
892 if (ext->oe_grants > 0)
893 osc_free_grant(cli, nr_pages, lost_grant, ext->oe_grants);
895 osc_extent_remove(ext);
896 /* put the refcount for RPC */
897 osc_extent_put(env, ext);
901 static int extent_wait_cb(struct osc_extent *ext, enum osc_extent_state state)
905 osc_object_lock(ext->oe_obj);
906 ret = ext->oe_state == state;
907 osc_object_unlock(ext->oe_obj);
913 * Wait for the extent's state to become @state.
915 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
916 enum osc_extent_state state)
918 struct osc_object *obj = ext->oe_obj;
919 struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(600), NULL,
920 LWI_ON_SIGNAL_NOOP, NULL);
924 osc_object_lock(obj);
925 LASSERT(sanity_check_nolock(ext) == 0);
926 /* `Kick' this extent only if the caller is waiting for it to be
928 if (state == OES_INV && !ext->oe_urgent && !ext->oe_hp) {
929 if (ext->oe_state == OES_ACTIVE) {
931 } else if (ext->oe_state == OES_CACHE) {
933 osc_extent_hold(ext);
937 osc_object_unlock(obj);
939 osc_extent_release(env, ext);
941 /* wait for the extent until its state becomes @state */
942 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state), &lwi);
943 if (rc == -ETIMEDOUT) {
944 OSC_EXTENT_DUMP(D_ERROR, ext,
945 "%s: wait ext to %u timedout, recovery in progress?\n",
946 cli_name(osc_cli(obj)), state);
948 lwi = LWI_INTR(NULL, NULL);
949 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state),
952 if (rc == 0 && ext->oe_rc < 0)
958 * Discard pages with index greater than @size. If @ext is overlapped with
959 * @size, then partial truncate happens.
961 static int osc_extent_truncate(struct osc_extent *ext, pgoff_t trunc_index,
964 struct cl_env_nest nest;
967 struct osc_object *obj = ext->oe_obj;
968 struct client_obd *cli = osc_cli(obj);
969 struct osc_async_page *oap;
970 struct osc_async_page *tmp;
971 int pages_in_chunk = 0;
972 int ppc_bits = cli->cl_chunkbits -
974 __u64 trunc_chunk = trunc_index >> ppc_bits;
980 LASSERT(sanity_check(ext) == 0);
981 LASSERT(ext->oe_state == OES_TRUNC);
982 LASSERT(!ext->oe_urgent);
984 /* Request new lu_env.
985 * We can't use that env from osc_cache_truncate_start() because
986 * it's from lov_io_sub and not fully initialized. */
987 env = cl_env_nested_get(&nest);
988 io = &osc_env_info(env)->oti_io;
989 io->ci_obj = cl_object_top(osc2cl(obj));
990 rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
994 /* discard all pages with index greater than trunc_index */
995 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
997 pgoff_t index = osc_index(oap2osc(oap));
998 struct cl_page *page = oap2cl_page(oap);
1000 LASSERT(list_empty(&oap->oap_rpc_item));
1002 /* only discard the pages with their index greater than
1003 * trunc_index, and ... */
1004 if (index < trunc_index ||
1005 (index == trunc_index && partial)) {
1006 /* accounting how many pages remaining in the chunk
1007 * so that we can calculate grants correctly. */
1008 if (index >> ppc_bits == trunc_chunk)
1013 list_del_init(&oap->oap_pending_item);
1016 lu_ref_add(&page->cp_reference, "truncate", current);
1018 if (cl_page_own(env, io, page) == 0) {
1019 cl_page_discard(env, io, page);
1020 cl_page_disown(env, io, page);
1022 LASSERT(page->cp_state == CPS_FREEING);
1026 lu_ref_del(&page->cp_reference, "truncate", current);
1027 cl_page_put(env, page);
1032 EASSERTF(ergo(ext->oe_start >= trunc_index + !!partial,
1033 ext->oe_nr_pages == 0),
1034 ext, "trunc_index %lu, partial %d\n", trunc_index, partial);
1036 osc_object_lock(obj);
1037 if (ext->oe_nr_pages == 0) {
1038 LASSERT(pages_in_chunk == 0);
1039 grants = ext->oe_grants;
1041 } else { /* calculate how many grants we can free */
1042 int chunks = (ext->oe_end >> ppc_bits) - trunc_chunk;
1046 /* if there is no pages in this chunk, we can also free grants
1047 * for the last chunk */
1048 if (pages_in_chunk == 0) {
1049 /* if this is the 1st chunk and no pages in this chunk,
1050 * ext->oe_nr_pages must be zero, so we should be in
1051 * the other if-clause. */
1052 LASSERT(trunc_chunk > 0);
1057 /* this is what we can free from this extent */
1058 grants = chunks << cli->cl_chunkbits;
1059 ext->oe_grants -= grants;
1060 last_index = ((trunc_chunk + 1) << ppc_bits) - 1;
1061 ext->oe_end = min(last_index, ext->oe_max_end);
1062 LASSERT(ext->oe_end >= ext->oe_start);
1063 LASSERT(ext->oe_grants > 0);
1065 osc_object_unlock(obj);
1067 if (grants > 0 || nr_pages > 0)
1068 osc_free_grant(cli, nr_pages, grants, grants);
1071 cl_io_fini(env, io);
1072 cl_env_nested_put(&nest, env);
1077 * This function is used to make the extent prepared for transfer.
1078 * A race with flusing page - ll_writepage() has to be handled cautiously.
1080 static int osc_extent_make_ready(const struct lu_env *env,
1081 struct osc_extent *ext)
1083 struct osc_async_page *oap;
1084 struct osc_async_page *last = NULL;
1085 struct osc_object *obj = ext->oe_obj;
1086 unsigned int page_count = 0;
1090 /* we're going to grab page lock, so object lock must not be taken. */
1091 LASSERT(sanity_check(ext) == 0);
1092 /* in locking state, any process should not touch this extent. */
1093 EASSERT(ext->oe_state == OES_LOCKING, ext);
1094 EASSERT(ext->oe_owner != NULL, ext);
1096 OSC_EXTENT_DUMP(D_CACHE, ext, "make ready\n");
1098 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1100 if (last == NULL || last->oap_obj_off < oap->oap_obj_off)
1103 /* checking ASYNC_READY is race safe */
1104 if ((oap->oap_async_flags & ASYNC_READY) != 0)
1107 rc = osc_make_ready(env, oap, OBD_BRW_WRITE);
1110 spin_lock(&oap->oap_lock);
1111 oap->oap_async_flags |= ASYNC_READY;
1112 spin_unlock(&oap->oap_lock);
1115 LASSERT((oap->oap_async_flags & ASYNC_READY) != 0);
1118 LASSERTF(0, "unknown return code: %d\n", rc);
1122 LASSERT(page_count == ext->oe_nr_pages);
1123 LASSERT(last != NULL);
1124 /* the last page is the only one we need to refresh its count by
1125 * the size of file. */
1126 if (!(last->oap_async_flags & ASYNC_COUNT_STABLE)) {
1127 int last_oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE);
1128 LASSERT(last_oap_count > 0);
1129 LASSERT(last->oap_page_off + last_oap_count <= PAGE_CACHE_SIZE);
1130 last->oap_count = last_oap_count;
1131 spin_lock(&last->oap_lock);
1132 last->oap_async_flags |= ASYNC_COUNT_STABLE;
1133 spin_unlock(&last->oap_lock);
1136 /* for the rest of pages, we don't need to call osf_refresh_count()
1137 * because it's known they are not the last page */
1138 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1139 if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
1140 oap->oap_count = PAGE_CACHE_SIZE - oap->oap_page_off;
1141 spin_lock(&oap->oap_lock);
1142 oap->oap_async_flags |= ASYNC_COUNT_STABLE;
1143 spin_unlock(&oap->oap_lock);
1147 osc_object_lock(obj);
1148 osc_extent_state_set(ext, OES_RPC);
1149 osc_object_unlock(obj);
1150 /* get a refcount for RPC. */
1151 osc_extent_get(ext);
1157 * Quick and simple version of osc_extent_find(). This function is frequently
1158 * called to expand the extent for the same IO. To expand the extent, the
1159 * page index must be in the same or next chunk of ext->oe_end.
1161 static int osc_extent_expand(struct osc_extent *ext, pgoff_t index,
1162 unsigned int *grants)
1164 struct osc_object *obj = ext->oe_obj;
1165 struct client_obd *cli = osc_cli(obj);
1166 struct osc_extent *next;
1167 int ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
1168 pgoff_t chunk = index >> ppc_bits;
1171 unsigned int chunksize = 1 << cli->cl_chunkbits;
1175 LASSERT(ext->oe_max_end >= index && ext->oe_start <= index);
1176 osc_object_lock(obj);
1177 LASSERT(sanity_check_nolock(ext) == 0);
1178 end_chunk = ext->oe_end >> ppc_bits;
1179 if (chunk > end_chunk + 1)
1180 GOTO(out, rc = -ERANGE);
1182 if (end_chunk >= chunk)
1185 LASSERT(end_chunk + 1 == chunk);
1187 /* try to expand this extent to cover @index */
1188 end_index = min(ext->oe_max_end, ((chunk + 1) << ppc_bits) - 1);
1190 /* don't go over the maximum extent size reported by server */
1191 if (end_index - ext->oe_start + 1 > cli->cl_max_extent_pages)
1192 GOTO(out, rc = -ERANGE);
1194 next = next_extent(ext);
1195 if (next != NULL && next->oe_start <= end_index)
1196 /* complex mode - overlapped with the next extent,
1197 * this case will be handled by osc_extent_find() */
1198 GOTO(out, rc = -EAGAIN);
1200 ext->oe_end = end_index;
1201 ext->oe_grants += chunksize;
1202 *grants -= chunksize;
1203 LASSERT(*grants >= 0);
1204 EASSERTF(osc_extent_is_overlapped(obj, ext) == 0, ext,
1205 "overlapped after expanding for %lu.\n", index);
1209 osc_object_unlock(obj);
1213 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
1214 const char *func, int line)
1216 struct osc_extent *ext;
1219 CDEBUG(level, "Dump object %p extents at %s:%d, mppr: %u.\n",
1220 obj, func, line, osc_cli(obj)->cl_max_pages_per_rpc);
1222 /* osc_object_lock(obj); */
1224 for (ext = first_extent(obj); ext != NULL; ext = next_extent(ext))
1225 OSC_EXTENT_DUMP(level, ext, "in tree %d.\n", cnt++);
1228 list_for_each_entry(ext, &obj->oo_hp_exts, oe_link)
1229 OSC_EXTENT_DUMP(level, ext, "hp %d.\n", cnt++);
1232 list_for_each_entry(ext, &obj->oo_urgent_exts, oe_link)
1233 OSC_EXTENT_DUMP(level, ext, "urgent %d.\n", cnt++);
1236 list_for_each_entry(ext, &obj->oo_reading_exts, oe_link)
1237 OSC_EXTENT_DUMP(level, ext, "reading %d.\n", cnt++);
1238 /* osc_object_unlock(obj); */
1241 /* ------------------ osc extent end ------------------ */
1243 static inline int osc_is_ready(struct osc_object *osc)
1245 return !list_empty(&osc->oo_ready_item) ||
1246 !list_empty(&osc->oo_hp_ready_item);
1249 #define OSC_IO_DEBUG(OSC, STR, args...) \
1250 CDEBUG(D_CACHE, "obj %p ready %d|%c|%c wr %d|%c|%c rd %d|%c " STR, \
1251 (OSC), osc_is_ready(OSC), \
1252 list_empty_marker(&(OSC)->oo_hp_ready_item), \
1253 list_empty_marker(&(OSC)->oo_ready_item), \
1254 atomic_read(&(OSC)->oo_nr_writes), \
1255 list_empty_marker(&(OSC)->oo_hp_exts), \
1256 list_empty_marker(&(OSC)->oo_urgent_exts), \
1257 atomic_read(&(OSC)->oo_nr_reads), \
1258 list_empty_marker(&(OSC)->oo_reading_exts), \
1261 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
1264 struct osc_page *opg = oap2osc_page(oap);
1265 struct cl_page *page = oap2cl_page(oap);
1268 LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
1271 result = cl_page_make_ready(env, page, CRT_WRITE);
1273 opg->ops_submit_time = cfs_time_current();
1277 static int osc_refresh_count(const struct lu_env *env,
1278 struct osc_async_page *oap, int cmd)
1280 struct osc_page *opg = oap2osc_page(oap);
1281 pgoff_t index = osc_index(oap2osc(oap));
1282 struct cl_object *obj;
1283 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
1288 /* readpage queues with _COUNT_STABLE, shouldn't get here. */
1289 LASSERT(!(cmd & OBD_BRW_READ));
1290 LASSERT(opg != NULL);
1291 obj = opg->ops_cl.cpl_obj;
1293 cl_object_attr_lock(obj);
1294 result = cl_object_attr_get(env, obj, attr);
1295 cl_object_attr_unlock(obj);
1298 kms = attr->cat_kms;
1299 if (cl_offset(obj, index) >= kms)
1300 /* catch race with truncate */
1302 else if (cl_offset(obj, index + 1) > kms)
1303 /* catch sub-page write at end of file */
1304 return kms % PAGE_CACHE_SIZE;
1306 return PAGE_CACHE_SIZE;
1309 static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
1312 struct osc_page *opg = oap2osc_page(oap);
1313 struct cl_page *page = oap2cl_page(oap);
1314 enum cl_req_type crt;
1319 cmd &= ~OBD_BRW_NOQUOTA;
1320 LASSERTF(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ),
1321 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1322 LASSERTF(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE),
1323 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1324 LASSERT(opg->ops_transfer_pinned);
1326 crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
1327 /* Clear opg->ops_transfer_pinned before VM lock is released. */
1328 opg->ops_transfer_pinned = 0;
1330 opg->ops_submit_time = 0;
1331 srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
1334 if (rc == 0 && srvlock) {
1335 struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
1336 struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
1337 size_t bytes = oap->oap_count;
1339 if (crt == CRT_READ)
1340 stats->os_lockless_reads += bytes;
1342 stats->os_lockless_writes += bytes;
1346 * This has to be the last operation with the page, as locks are
1347 * released in cl_page_completion() and nothing except for the
1348 * reference counter protects page from concurrent reclaim.
1350 lu_ref_del(&page->cp_reference, "transfer", page);
1352 cl_page_completion(env, page, crt, rc);
1353 cl_page_put(env, page);
1358 #define OSC_DUMP_GRANT(lvl, cli, fmt, args...) do { \
1359 struct client_obd *__tmp = (cli); \
1360 CDEBUG(lvl, "%s: grant { dirty: %ld/%ld dirty_pages: %ld/%lu " \
1361 "dropped: %ld avail: %ld, dirty_grant: %ld, " \
1362 "reserved: %ld, flight: %d } lru {in list: %ld, " \
1363 "left: %ld, waiters: %d }" fmt "\n", \
1365 __tmp->cl_dirty_pages, __tmp->cl_dirty_max_pages, \
1366 atomic_long_read(&obd_dirty_pages), obd_max_dirty_pages, \
1367 __tmp->cl_lost_grant, __tmp->cl_avail_grant, \
1368 __tmp->cl_dirty_grant, \
1369 __tmp->cl_reserved_grant, __tmp->cl_w_in_flight, \
1370 atomic_long_read(&__tmp->cl_lru_in_list), \
1371 atomic_long_read(&__tmp->cl_lru_busy), \
1372 atomic_read(&__tmp->cl_lru_shrinkers), ##args); \
1375 /* caller must hold loi_list_lock */
1376 static void osc_consume_write_grant(struct client_obd *cli,
1377 struct brw_page *pga)
1379 assert_spin_locked(&cli->cl_loi_list_lock);
1380 LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
1381 atomic_long_inc(&obd_dirty_pages);
1382 cli->cl_dirty_pages++;
1383 pga->flag |= OBD_BRW_FROM_GRANT;
1384 CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
1385 PAGE_CACHE_SIZE, pga, pga->pg);
1386 osc_update_next_shrink(cli);
1389 /* the companion to osc_consume_write_grant, called when a brw has completed.
1390 * must be called with the loi lock held. */
1391 static void osc_release_write_grant(struct client_obd *cli,
1392 struct brw_page *pga)
1396 assert_spin_locked(&cli->cl_loi_list_lock);
1397 if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
1402 pga->flag &= ~OBD_BRW_FROM_GRANT;
1403 atomic_long_dec(&obd_dirty_pages);
1404 cli->cl_dirty_pages--;
1405 if (pga->flag & OBD_BRW_NOCACHE) {
1406 pga->flag &= ~OBD_BRW_NOCACHE;
1407 atomic_long_dec(&obd_dirty_transit_pages);
1408 cli->cl_dirty_transit--;
1414 * To avoid sleeping with object lock held, it's good for us allocate enough
1415 * grants before entering into critical section.
1417 * client_obd_list_lock held by caller
1419 static int osc_reserve_grant(struct client_obd *cli, unsigned int bytes)
1423 if (cli->cl_avail_grant >= bytes) {
1424 cli->cl_avail_grant -= bytes;
1425 cli->cl_reserved_grant += bytes;
1431 static void __osc_unreserve_grant(struct client_obd *cli,
1432 unsigned int reserved, unsigned int unused)
1434 /* it's quite normal for us to get more grant than reserved.
1435 * Thinking about a case that two extents merged by adding a new
1436 * chunk, we can save one extent tax. If extent tax is greater than
1437 * one chunk, we can save more grant by adding a new chunk */
1438 cli->cl_reserved_grant -= reserved;
1439 if (unused > reserved) {
1440 cli->cl_avail_grant += reserved;
1441 cli->cl_lost_grant += unused - reserved;
1442 cli->cl_dirty_grant -= unused - reserved;
1444 cli->cl_avail_grant += unused;
1445 cli->cl_dirty_grant += reserved - unused;
1449 static void osc_unreserve_grant(struct client_obd *cli,
1450 unsigned int reserved, unsigned int unused)
1452 spin_lock(&cli->cl_loi_list_lock);
1453 __osc_unreserve_grant(cli, reserved, unused);
1455 osc_wake_cache_waiters(cli);
1456 spin_unlock(&cli->cl_loi_list_lock);
1460 * Free grant after IO is finished or canceled.
1462 * @lost_grant is used to remember how many grants we have allocated but not
1463 * used, we should return these grants to OST. There're two cases where grants
1466 * 2. blocksize at OST is less than PAGE_CACHE_SIZE and a partial page was
1467 * written. In this case OST may use less chunks to serve this partial
1468 * write. OSTs don't actually know the page size on the client side. so
1469 * clients have to calculate lost grant by the blocksize on the OST.
1470 * See filter_grant_check() for details.
1472 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
1473 unsigned int lost_grant, unsigned int dirty_grant)
1475 unsigned long grant;
1477 grant = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
1479 spin_lock(&cli->cl_loi_list_lock);
1480 atomic_long_sub(nr_pages, &obd_dirty_pages);
1481 cli->cl_dirty_pages -= nr_pages;
1482 cli->cl_lost_grant += lost_grant;
1483 cli->cl_dirty_grant -= dirty_grant;
1484 if (cli->cl_avail_grant < grant && cli->cl_lost_grant >= grant) {
1485 /* borrow some grant from truncate to avoid the case that
1486 * truncate uses up all avail grant */
1487 cli->cl_lost_grant -= grant;
1488 cli->cl_avail_grant += grant;
1490 osc_wake_cache_waiters(cli);
1491 spin_unlock(&cli->cl_loi_list_lock);
1492 CDEBUG(D_CACHE, "lost %u grant: %lu avail: %lu dirty: %lu/%lu\n",
1493 lost_grant, cli->cl_lost_grant,
1494 cli->cl_avail_grant, cli->cl_dirty_pages << PAGE_CACHE_SHIFT,
1495 cli->cl_dirty_grant);
1499 * The companion to osc_enter_cache(), called when @oap is no longer part of
1500 * the dirty accounting due to error.
1502 static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap)
1504 spin_lock(&cli->cl_loi_list_lock);
1505 osc_release_write_grant(cli, &oap->oap_brw_page);
1506 spin_unlock(&cli->cl_loi_list_lock);
1510 * Non-blocking version of osc_enter_cache() that consumes grant only when it
1513 static int osc_enter_cache_try(struct client_obd *cli,
1514 struct osc_async_page *oap,
1515 int bytes, int transient)
1519 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1521 rc = osc_reserve_grant(cli, bytes);
1525 if (cli->cl_dirty_pages < cli->cl_dirty_max_pages &&
1526 1 + atomic_long_read(&obd_dirty_pages) <= obd_max_dirty_pages) {
1527 osc_consume_write_grant(cli, &oap->oap_brw_page);
1529 cli->cl_dirty_transit++;
1530 atomic_long_inc(&obd_dirty_transit_pages);
1531 oap->oap_brw_flags |= OBD_BRW_NOCACHE;
1535 __osc_unreserve_grant(cli, bytes, bytes);
1541 static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
1544 spin_lock(&cli->cl_loi_list_lock);
1545 rc = list_empty(&ocw->ocw_entry);
1546 spin_unlock(&cli->cl_loi_list_lock);
1551 * The main entry to reserve dirty page accounting. Usually the grant reserved
1552 * in this function will be freed in bulk in osc_free_grant() unless it fails
1553 * to add osc cache, in that case, it will be freed in osc_exit_cache().
1555 * The process will be put into sleep if it's already run out of grant.
1557 static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
1558 struct osc_async_page *oap, int bytes)
1560 struct osc_object *osc = oap->oap_obj;
1561 struct lov_oinfo *loi = osc->oo_oinfo;
1562 struct osc_cache_waiter ocw;
1563 struct l_wait_info lwi;
1567 lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(AT_OFF ? obd_timeout : at_max),
1568 NULL, LWI_ON_SIGNAL_NOOP, NULL);
1570 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1572 spin_lock(&cli->cl_loi_list_lock);
1574 /* force the caller to try sync io. this can jump the list
1575 * of queued writes and create a discontiguous rpc stream */
1576 if (OBD_FAIL_CHECK(OBD_FAIL_OSC_NO_GRANT) ||
1577 cli->cl_dirty_max_pages == 0 ||
1578 cli->cl_ar.ar_force_sync || loi->loi_ar.ar_force_sync) {
1579 OSC_DUMP_GRANT(D_CACHE, cli, "forced sync i/o\n");
1580 GOTO(out, rc = -EDQUOT);
1583 /* Hopefully normal case - cache space and write credits available */
1584 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1585 OSC_DUMP_GRANT(D_CACHE, cli, "granted from cache\n");
1589 /* We can get here for two reasons: too many dirty pages in cache, or
1590 * run out of grants. In both cases we should write dirty pages out.
1591 * Adding a cache waiter will trigger urgent write-out no matter what
1593 * The exiting condition is no avail grants and no dirty pages caching,
1594 * that really means there is no space on the OST. */
1595 init_waitqueue_head(&ocw.ocw_waitq);
1597 ocw.ocw_grant = bytes;
1598 while (cli->cl_dirty_pages > 0 || cli->cl_w_in_flight > 0) {
1599 list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
1601 spin_unlock(&cli->cl_loi_list_lock);
1603 osc_io_unplug_async(env, cli, NULL);
1605 CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
1606 cli_name(cli), &ocw, oap);
1608 rc = l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
1610 spin_lock(&cli->cl_loi_list_lock);
1613 /* l_wait_event is interrupted by signal or timed out */
1614 list_del_init(&ocw.ocw_entry);
1617 LASSERT(list_empty(&ocw.ocw_entry));
1622 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1630 OSC_DUMP_GRANT(D_CACHE, cli, "finally got grant space\n");
1633 OSC_DUMP_GRANT(D_CACHE, cli,
1634 "timeout, fall back to sync i/o\n");
1635 osc_extent_tree_dump(D_CACHE, osc);
1636 /* fall back to synchronous I/O */
1640 /* Ensures restartability - LU-3581 */
1641 OSC_DUMP_GRANT(D_CACHE, cli, "interrupted\n");
1645 OSC_DUMP_GRANT(D_CACHE, cli,
1646 "no grant space, fall back to sync i/o\n");
1649 CDEBUG(D_CACHE, "%s: event for cache space @ %p never arrived "
1650 "due to %d, fall back to sync i/o\n",
1651 cli_name(cli), &ocw, rc);
1656 spin_unlock(&cli->cl_loi_list_lock);
1660 /* caller must hold loi_list_lock */
1661 void osc_wake_cache_waiters(struct client_obd *cli)
1663 struct list_head *l, *tmp;
1664 struct osc_cache_waiter *ocw;
1667 list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
1668 ocw = list_entry(l, struct osc_cache_waiter, ocw_entry);
1669 list_del_init(&ocw->ocw_entry);
1671 ocw->ocw_rc = -EDQUOT;
1672 /* we can't dirty more */
1673 if ((cli->cl_dirty_pages >= cli->cl_dirty_max_pages) ||
1674 (1 + atomic_long_read(&obd_dirty_pages) >
1675 obd_max_dirty_pages)) {
1676 CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
1677 "osc max %ld, sys max %ld\n",
1678 cli->cl_dirty_pages, cli->cl_dirty_max_pages,
1679 obd_max_dirty_pages);
1683 if (osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
1686 CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
1687 ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
1689 wake_up(&ocw->ocw_waitq);
1695 static int osc_max_rpc_in_flight(struct client_obd *cli, struct osc_object *osc)
1697 int hprpc = !!list_empty(&osc->oo_hp_exts);
1698 return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
1701 /* This maintains the lists of pending pages to read/write for a given object
1702 * (lop). This is used by osc_check_rpcs->osc_next_obj() and osc_list_maint()
1703 * to quickly find objects that are ready to send an RPC. */
1704 static int osc_makes_rpc(struct client_obd *cli, struct osc_object *osc,
1707 int invalid_import = 0;
1710 /* if we have an invalid import we want to drain the queued pages
1711 * by forcing them through rpcs that immediately fail and complete
1712 * the pages. recovery relies on this to empty the queued pages
1713 * before canceling the locks and evicting down the llite pages */
1714 if ((cli->cl_import == NULL || cli->cl_import->imp_invalid))
1717 if (cmd & OBD_BRW_WRITE) {
1718 if (atomic_read(&osc->oo_nr_writes) == 0)
1720 if (invalid_import) {
1721 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1724 if (!list_empty(&osc->oo_hp_exts)) {
1725 CDEBUG(D_CACHE, "high prio request forcing RPC\n");
1728 if (!list_empty(&osc->oo_urgent_exts)) {
1729 CDEBUG(D_CACHE, "urgent request forcing RPC\n");
1732 /* trigger a write rpc stream as long as there are dirtiers
1733 * waiting for space. as they're waiting, they're not going to
1734 * create more pages to coalesce with what's waiting.. */
1735 if (!list_empty(&cli->cl_cache_waiters)) {
1736 CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
1739 if (atomic_read(&osc->oo_nr_writes) >=
1740 cli->cl_max_pages_per_rpc)
1743 if (atomic_read(&osc->oo_nr_reads) == 0)
1745 if (invalid_import) {
1746 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1749 /* all read are urgent. */
1750 if (!list_empty(&osc->oo_reading_exts))
1757 static void osc_update_pending(struct osc_object *obj, int cmd, int delta)
1759 struct client_obd *cli = osc_cli(obj);
1760 if (cmd & OBD_BRW_WRITE) {
1761 atomic_add(delta, &obj->oo_nr_writes);
1762 atomic_add(delta, &cli->cl_pending_w_pages);
1763 LASSERT(atomic_read(&obj->oo_nr_writes) >= 0);
1765 atomic_add(delta, &obj->oo_nr_reads);
1766 atomic_add(delta, &cli->cl_pending_r_pages);
1767 LASSERT(atomic_read(&obj->oo_nr_reads) >= 0);
1769 OSC_IO_DEBUG(obj, "update pending cmd %d delta %d.\n", cmd, delta);
1772 static int osc_makes_hprpc(struct osc_object *obj)
1774 return !list_empty(&obj->oo_hp_exts);
1777 static void on_list(struct list_head *item, struct list_head *list,
1780 if (list_empty(item) && should_be_on)
1781 list_add_tail(item, list);
1782 else if (!list_empty(item) && !should_be_on)
1783 list_del_init(item);
1786 /* maintain the osc's cli list membership invariants so that osc_send_oap_rpc
1787 * can find pages to build into rpcs quickly */
1788 static int __osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1790 if (osc_makes_hprpc(osc)) {
1792 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list, 0);
1793 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
1795 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
1796 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list,
1797 osc_makes_rpc(cli, osc, OBD_BRW_WRITE) ||
1798 osc_makes_rpc(cli, osc, OBD_BRW_READ));
1801 on_list(&osc->oo_write_item, &cli->cl_loi_write_list,
1802 atomic_read(&osc->oo_nr_writes) > 0);
1804 on_list(&osc->oo_read_item, &cli->cl_loi_read_list,
1805 atomic_read(&osc->oo_nr_reads) > 0);
1807 return osc_is_ready(osc);
1810 static int osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1814 spin_lock(&cli->cl_loi_list_lock);
1815 is_ready = __osc_list_maint(cli, osc);
1816 spin_unlock(&cli->cl_loi_list_lock);
1821 /* this is trying to propogate async writeback errors back up to the
1822 * application. As an async write fails we record the error code for later if
1823 * the app does an fsync. As long as errors persist we force future rpcs to be
1824 * sync so that the app can get a sync error and break the cycle of queueing
1825 * pages for which writeback will fail. */
1826 static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
1833 ar->ar_force_sync = 1;
1834 ar->ar_min_xid = ptlrpc_sample_next_xid();
1839 if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
1840 ar->ar_force_sync = 0;
1843 /* this must be called holding the loi list lock to give coverage to exit_cache,
1844 * async_flag maintenance, and oap_request */
1845 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
1846 struct osc_async_page *oap, int sent, int rc)
1848 struct osc_object *osc = oap->oap_obj;
1849 struct lov_oinfo *loi = osc->oo_oinfo;
1853 if (oap->oap_request != NULL) {
1854 xid = ptlrpc_req_xid(oap->oap_request);
1855 ptlrpc_req_finished(oap->oap_request);
1856 oap->oap_request = NULL;
1859 /* As the transfer for this page is being done, clear the flags */
1860 spin_lock(&oap->oap_lock);
1861 oap->oap_async_flags = 0;
1862 spin_unlock(&oap->oap_lock);
1863 oap->oap_interrupted = 0;
1865 if (oap->oap_cmd & OBD_BRW_WRITE && xid > 0) {
1866 spin_lock(&cli->cl_loi_list_lock);
1867 osc_process_ar(&cli->cl_ar, xid, rc);
1868 osc_process_ar(&loi->loi_ar, xid, rc);
1869 spin_unlock(&cli->cl_loi_list_lock);
1872 rc = osc_completion(env, oap, oap->oap_cmd, rc);
1874 CERROR("completion on oap %p obj %p returns %d.\n",
1881 * Try to add extent to one RPC. We need to think about the following things:
1882 * - # of pages must not be over max_pages_per_rpc
1883 * - extent must be compatible with previous ones
1885 static int try_to_add_extent_for_io(struct client_obd *cli,
1886 struct osc_extent *ext,
1887 struct list_head *rpclist,
1888 unsigned int *pc, unsigned int *max_pages)
1890 struct osc_extent *tmp;
1891 struct osc_async_page *oap = list_first_entry(&ext->oe_pages,
1892 struct osc_async_page,
1896 EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE),
1899 *max_pages = max(ext->oe_mppr, *max_pages);
1900 if (*pc + ext->oe_nr_pages > *max_pages)
1903 list_for_each_entry(tmp, rpclist, oe_link) {
1904 struct osc_async_page *oap2;
1905 oap2 = list_first_entry(&tmp->oe_pages, struct osc_async_page,
1907 EASSERT(tmp->oe_owner == current, tmp);
1909 if (overlapped(tmp, ext)) {
1910 OSC_EXTENT_DUMP(D_ERROR, tmp, "overlapped %p.\n", ext);
1914 if (oap2cl_page(oap)->cp_type != oap2cl_page(oap2)->cp_type) {
1915 CDEBUG(D_CACHE, "Do not permit different type of IO"
1916 " for a same RPC\n");
1920 if (tmp->oe_srvlock != ext->oe_srvlock ||
1921 !tmp->oe_grants != !ext->oe_grants ||
1922 tmp->oe_no_merge || ext->oe_no_merge)
1925 /* remove break for strict check */
1929 *pc += ext->oe_nr_pages;
1930 list_move_tail(&ext->oe_link, rpclist);
1931 ext->oe_owner = current;
1936 * In order to prevent multiple ptlrpcd from breaking contiguous extents,
1937 * get_write_extent() takes all appropriate extents in atomic.
1939 * The following policy is used to collect extents for IO:
1940 * 1. Add as many HP extents as possible;
1941 * 2. Add the first urgent extent in urgent extent list and take it out of
1943 * 3. Add subsequent extents of this urgent extent;
1944 * 4. If urgent list is not empty, goto 2;
1945 * 5. Traverse the extent tree from the 1st extent;
1946 * 6. Above steps exit if there is no space in this RPC.
1948 static unsigned int get_write_extents(struct osc_object *obj,
1949 struct list_head *rpclist)
1951 struct client_obd *cli = osc_cli(obj);
1952 struct osc_extent *ext;
1953 unsigned int page_count = 0;
1954 unsigned int max_pages = cli->cl_max_pages_per_rpc;
1956 LASSERT(osc_object_is_locked(obj));
1957 while (!list_empty(&obj->oo_hp_exts)) {
1958 ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
1960 LASSERT(ext->oe_state == OES_CACHE);
1961 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1964 EASSERT(ext->oe_nr_pages <= max_pages, ext);
1966 if (page_count == max_pages)
1969 while (!list_empty(&obj->oo_urgent_exts)) {
1970 ext = list_entry(obj->oo_urgent_exts.next,
1971 struct osc_extent, oe_link);
1972 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1976 if (!ext->oe_intree)
1979 while ((ext = next_extent(ext)) != NULL) {
1980 if ((ext->oe_state != OES_CACHE) ||
1981 (!list_empty(&ext->oe_link) &&
1982 ext->oe_owner != NULL))
1985 if (!try_to_add_extent_for_io(cli, ext, rpclist,
1986 &page_count, &max_pages))
1990 if (page_count == max_pages)
1993 ext = first_extent(obj);
1994 while (ext != NULL) {
1995 if ((ext->oe_state != OES_CACHE) ||
1996 /* this extent may be already in current rpclist */
1997 (!list_empty(&ext->oe_link) && ext->oe_owner != NULL)) {
1998 ext = next_extent(ext);
2002 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
2006 ext = next_extent(ext);
2012 osc_send_write_rpc(const struct lu_env *env, struct client_obd *cli,
2013 struct osc_object *osc)
2016 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2017 struct osc_extent *ext;
2018 struct osc_extent *tmp;
2019 struct osc_extent *first = NULL;
2020 unsigned int page_count = 0;
2025 LASSERT(osc_object_is_locked(osc));
2027 page_count = get_write_extents(osc, &rpclist);
2028 LASSERT(equi(page_count == 0, list_empty(&rpclist)));
2030 if (list_empty(&rpclist))
2033 osc_update_pending(osc, OBD_BRW_WRITE, -page_count);
2035 list_for_each_entry(ext, &rpclist, oe_link) {
2036 LASSERT(ext->oe_state == OES_CACHE ||
2037 ext->oe_state == OES_LOCK_DONE);
2038 if (ext->oe_state == OES_CACHE)
2039 osc_extent_state_set(ext, OES_LOCKING);
2041 osc_extent_state_set(ext, OES_RPC);
2044 /* we're going to grab page lock, so release object lock because
2045 * lock order is page lock -> object lock. */
2046 osc_object_unlock(osc);
2048 list_for_each_entry_safe(ext, tmp, &rpclist, oe_link) {
2049 if (ext->oe_state == OES_LOCKING) {
2050 rc = osc_extent_make_ready(env, ext);
2051 if (unlikely(rc < 0)) {
2052 list_del_init(&ext->oe_link);
2053 osc_extent_finish(env, ext, 0, rc);
2057 if (first == NULL) {
2059 srvlock = ext->oe_srvlock;
2061 LASSERT(srvlock == ext->oe_srvlock);
2065 if (!list_empty(&rpclist)) {
2066 LASSERT(page_count > 0);
2067 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_WRITE);
2068 LASSERT(list_empty(&rpclist));
2071 osc_object_lock(osc);
2076 * prepare pages for ASYNC io and put pages in send queue.
2078 * \param cmd OBD_BRW_* macroses
2079 * \param lop pending pages
2081 * \return zero if no page added to send queue.
2082 * \return 1 if pages successfully added to send queue.
2083 * \return negative on errors.
2086 osc_send_read_rpc(const struct lu_env *env, struct client_obd *cli,
2087 struct osc_object *osc)
2090 struct osc_extent *ext;
2091 struct osc_extent *next;
2092 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2093 unsigned int page_count = 0;
2094 unsigned int max_pages = cli->cl_max_pages_per_rpc;
2098 LASSERT(osc_object_is_locked(osc));
2099 list_for_each_entry_safe(ext, next,
2100 &osc->oo_reading_exts, oe_link) {
2101 EASSERT(ext->oe_state == OES_LOCK_DONE, ext);
2102 if (!try_to_add_extent_for_io(cli, ext, &rpclist, &page_count,
2105 osc_extent_state_set(ext, OES_RPC);
2106 EASSERT(ext->oe_nr_pages <= max_pages, ext);
2108 LASSERT(page_count <= max_pages);
2110 osc_update_pending(osc, OBD_BRW_READ, -page_count);
2112 if (!list_empty(&rpclist)) {
2113 osc_object_unlock(osc);
2115 LASSERT(page_count > 0);
2116 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_READ);
2117 LASSERT(list_empty(&rpclist));
2119 osc_object_lock(osc);
2124 #define list_to_obj(list, item) ({ \
2125 struct list_head *__tmp = (list)->next; \
2126 list_del_init(__tmp); \
2127 list_entry(__tmp, struct osc_object, oo_##item); \
2130 /* This is called by osc_check_rpcs() to find which objects have pages that
2131 * we could be sending. These lists are maintained by osc_makes_rpc(). */
2132 static struct osc_object *osc_next_obj(struct client_obd *cli)
2136 /* First return objects that have blocked locks so that they
2137 * will be flushed quickly and other clients can get the lock,
2138 * then objects which have pages ready to be stuffed into RPCs */
2139 if (!list_empty(&cli->cl_loi_hp_ready_list))
2140 RETURN(list_to_obj(&cli->cl_loi_hp_ready_list, hp_ready_item));
2141 if (!list_empty(&cli->cl_loi_ready_list))
2142 RETURN(list_to_obj(&cli->cl_loi_ready_list, ready_item));
2144 /* then if we have cache waiters, return all objects with queued
2145 * writes. This is especially important when many small files
2146 * have filled up the cache and not been fired into rpcs because
2147 * they don't pass the nr_pending/object threshhold */
2148 if (!list_empty(&cli->cl_cache_waiters) &&
2149 !list_empty(&cli->cl_loi_write_list))
2150 RETURN(list_to_obj(&cli->cl_loi_write_list, write_item));
2152 /* then return all queued objects when we have an invalid import
2153 * so that they get flushed */
2154 if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
2155 if (!list_empty(&cli->cl_loi_write_list))
2156 RETURN(list_to_obj(&cli->cl_loi_write_list,
2158 if (!list_empty(&cli->cl_loi_read_list))
2159 RETURN(list_to_obj(&cli->cl_loi_read_list,
2165 /* called with the loi list lock held */
2166 static void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli)
2167 __must_hold(&cli->cl_loi_list_lock)
2169 struct osc_object *osc;
2173 while ((osc = osc_next_obj(cli)) != NULL) {
2174 struct cl_object *obj = osc2cl(osc);
2175 struct lu_ref_link link;
2177 OSC_IO_DEBUG(osc, "%lu in flight\n", rpcs_in_flight(cli));
2179 if (osc_max_rpc_in_flight(cli, osc)) {
2180 __osc_list_maint(cli, osc);
2185 spin_unlock(&cli->cl_loi_list_lock);
2186 lu_object_ref_add_at(&obj->co_lu, &link, "check", current);
2188 /* attempt some read/write balancing by alternating between
2189 * reads and writes in an object. The makes_rpc checks here
2190 * would be redundant if we were getting read/write work items
2191 * instead of objects. we don't want send_oap_rpc to drain a
2192 * partial read pending queue when we're given this object to
2193 * do io on writes while there are cache waiters */
2194 osc_object_lock(osc);
2195 if (osc_makes_rpc(cli, osc, OBD_BRW_WRITE)) {
2196 rc = osc_send_write_rpc(env, cli, osc);
2198 CERROR("Write request failed with %d\n", rc);
2200 /* osc_send_write_rpc failed, mostly because of
2203 * It can't break here, because if:
2204 * - a page was submitted by osc_io_submit, so
2206 * - no request in flight
2207 * - no subsequent request
2208 * The system will be in live-lock state,
2209 * because there is no chance to call
2210 * osc_io_unplug() and osc_check_rpcs() any
2211 * more. pdflush can't help in this case,
2212 * because it might be blocked at grabbing
2213 * the page lock as we mentioned.
2215 * Anyway, continue to drain pages. */
2219 if (osc_makes_rpc(cli, osc, OBD_BRW_READ)) {
2220 rc = osc_send_read_rpc(env, cli, osc);
2222 CERROR("Read request failed with %d\n", rc);
2224 osc_object_unlock(osc);
2226 osc_list_maint(cli, osc);
2227 lu_object_ref_del_at(&obj->co_lu, &link, "check", current);
2228 cl_object_put(env, obj);
2230 spin_lock(&cli->cl_loi_list_lock);
2234 static int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
2235 struct osc_object *osc, int async)
2239 if (osc != NULL && osc_list_maint(cli, osc) == 0)
2243 spin_lock(&cli->cl_loi_list_lock);
2244 osc_check_rpcs(env, cli);
2245 spin_unlock(&cli->cl_loi_list_lock);
2247 CDEBUG(D_CACHE, "Queue writeback work for client %p.\n", cli);
2248 LASSERT(cli->cl_writeback_work != NULL);
2249 rc = ptlrpcd_queue_work(cli->cl_writeback_work);
2254 static int osc_io_unplug_async(const struct lu_env *env,
2255 struct client_obd *cli, struct osc_object *osc)
2257 return osc_io_unplug0(env, cli, osc, 1);
2260 void osc_io_unplug(const struct lu_env *env, struct client_obd *cli,
2261 struct osc_object *osc)
2263 (void)osc_io_unplug0(env, cli, osc, 0);
2266 int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
2267 struct page *page, loff_t offset)
2269 struct obd_export *exp = osc_export(osc);
2270 struct osc_async_page *oap = &ops->ops_oap;
2274 return cfs_size_round(sizeof(*oap));
2276 oap->oap_magic = OAP_MAGIC;
2277 oap->oap_cli = &exp->exp_obd->u.cli;
2280 oap->oap_page = page;
2281 oap->oap_obj_off = offset;
2282 LASSERT(!(offset & ~PAGE_MASK));
2284 if (!client_is_remote(exp) && cfs_capable(CFS_CAP_SYS_RESOURCE))
2285 oap->oap_brw_flags = OBD_BRW_NOQUOTA;
2287 INIT_LIST_HEAD(&oap->oap_pending_item);
2288 INIT_LIST_HEAD(&oap->oap_rpc_item);
2290 spin_lock_init(&oap->oap_lock);
2291 CDEBUG(D_INFO, "oap %p page %p obj off "LPU64"\n",
2292 oap, page, oap->oap_obj_off);
2296 int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
2297 struct osc_page *ops)
2299 struct osc_io *oio = osc_env_io(env);
2300 struct osc_extent *ext = NULL;
2301 struct osc_async_page *oap = &ops->ops_oap;
2302 struct client_obd *cli = oap->oap_cli;
2303 struct osc_object *osc = oap->oap_obj;
2306 unsigned int grants = 0;
2307 u32 brw_flags = OBD_BRW_ASYNC;
2308 int cmd = OBD_BRW_WRITE;
2309 int need_release = 0;
2313 if (oap->oap_magic != OAP_MAGIC)
2316 if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
2319 if (!list_empty(&oap->oap_pending_item) ||
2320 !list_empty(&oap->oap_rpc_item))
2323 /* Set the OBD_BRW_SRVLOCK before the page is queued. */
2324 brw_flags |= ops->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
2325 if (!client_is_remote(osc_export(osc)) &&
2326 cfs_capable(CFS_CAP_SYS_RESOURCE)) {
2327 brw_flags |= OBD_BRW_NOQUOTA;
2328 cmd |= OBD_BRW_NOQUOTA;
2331 /* check if the file's owner/group is over quota */
2332 if (!(cmd & OBD_BRW_NOQUOTA)) {
2333 struct cl_object *obj;
2334 struct cl_attr *attr;
2335 unsigned int qid[MAXQUOTAS];
2337 obj = cl_object_top(&osc->oo_cl);
2338 attr = &osc_env_info(env)->oti_attr;
2340 cl_object_attr_lock(obj);
2341 rc = cl_object_attr_get(env, obj, attr);
2342 cl_object_attr_unlock(obj);
2344 qid[USRQUOTA] = attr->cat_uid;
2345 qid[GRPQUOTA] = attr->cat_gid;
2346 if (rc == 0 && osc_quota_chkdq(cli, qid) == NO_QUOTA)
2353 oap->oap_page_off = ops->ops_from;
2354 oap->oap_count = ops->ops_to - ops->ops_from;
2355 /* No need to hold a lock here,
2356 * since this page is not in any list yet. */
2357 oap->oap_async_flags = 0;
2358 oap->oap_brw_flags = brw_flags;
2360 OSC_IO_DEBUG(osc, "oap %p page %p added for cmd %d\n",
2361 oap, oap->oap_page, oap->oap_cmd & OBD_BRW_RWMASK);
2363 index = osc_index(oap2osc(oap));
2365 /* Add this page into extent by the following steps:
2366 * 1. if there exists an active extent for this IO, mostly this page
2367 * can be added to the active extent and sometimes we need to
2368 * expand extent to accomodate this page;
2369 * 2. otherwise, a new extent will be allocated. */
2371 ext = oio->oi_active;
2372 if (ext != NULL && ext->oe_start <= index && ext->oe_max_end >= index) {
2373 /* one chunk plus extent overhead must be enough to write this
2375 grants = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
2376 if (ext->oe_end >= index)
2379 /* it doesn't need any grant to dirty this page */
2380 spin_lock(&cli->cl_loi_list_lock);
2381 rc = osc_enter_cache_try(cli, oap, grants, 0);
2382 spin_unlock(&cli->cl_loi_list_lock);
2383 if (rc == 0) { /* try failed */
2386 } else if (ext->oe_end < index) {
2388 /* try to expand this extent */
2389 rc = osc_extent_expand(ext, index, &tmp);
2392 /* don't free reserved grant */
2394 OSC_EXTENT_DUMP(D_CACHE, ext,
2395 "expanded for %lu.\n", index);
2396 osc_unreserve_grant(cli, grants, tmp);
2401 } else if (ext != NULL) {
2402 /* index is located outside of active extent */
2406 osc_extent_release(env, ext);
2407 oio->oi_active = NULL;
2412 tmp = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
2414 /* try to find new extent to cover this page */
2415 LASSERT(oio->oi_active == NULL);
2416 /* we may have allocated grant for this page if we failed
2417 * to expand the previous active extent. */
2418 LASSERT(ergo(grants > 0, grants >= tmp));
2422 /* we haven't allocated grant for this page. */
2423 rc = osc_enter_cache(env, cli, oap, tmp);
2430 ext = osc_extent_find(env, osc, index, &tmp);
2432 LASSERT(tmp == grants);
2433 osc_exit_cache(cli, oap);
2437 oio->oi_active = ext;
2441 osc_unreserve_grant(cli, grants, tmp);
2444 LASSERT(ergo(rc == 0, ext != NULL));
2446 EASSERTF(ext->oe_end >= index && ext->oe_start <= index,
2447 ext, "index = %lu.\n", index);
2448 LASSERT((oap->oap_brw_flags & OBD_BRW_FROM_GRANT) != 0);
2450 osc_object_lock(osc);
2451 if (ext->oe_nr_pages == 0)
2452 ext->oe_srvlock = ops->ops_srvlock;
2454 LASSERT(ext->oe_srvlock == ops->ops_srvlock);
2456 list_add_tail(&oap->oap_pending_item, &ext->oe_pages);
2457 osc_object_unlock(osc);
2462 int osc_teardown_async_page(const struct lu_env *env,
2463 struct osc_object *obj, struct osc_page *ops)
2465 struct osc_async_page *oap = &ops->ops_oap;
2469 LASSERT(oap->oap_magic == OAP_MAGIC);
2471 CDEBUG(D_INFO, "teardown oap %p page %p at index %lu.\n",
2472 oap, ops, osc_index(oap2osc(oap)));
2474 if (!list_empty(&oap->oap_rpc_item)) {
2475 CDEBUG(D_CACHE, "oap %p is not in cache.\n", oap);
2477 } else if (!list_empty(&oap->oap_pending_item)) {
2478 struct osc_extent *ext = NULL;
2480 osc_object_lock(obj);
2481 ext = osc_extent_lookup(obj, osc_index(oap2osc(oap)));
2482 osc_object_unlock(obj);
2483 /* only truncated pages are allowed to be taken out.
2484 * See osc_extent_truncate() and osc_cache_truncate_start()
2486 if (ext != NULL && ext->oe_state != OES_TRUNC) {
2487 OSC_EXTENT_DUMP(D_ERROR, ext, "trunc at %lu.\n",
2488 osc_index(oap2osc(oap)));
2492 osc_extent_put(env, ext);
2498 * This is called when a page is picked up by kernel to write out.
2500 * We should find out the corresponding extent and add the whole extent
2501 * into urgent list. The extent may be being truncated or used, handle it
2504 int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
2505 struct osc_page *ops)
2507 struct osc_extent *ext = NULL;
2508 struct osc_object *obj = cl2osc(ops->ops_cl.cpl_obj);
2509 struct cl_page *cp = ops->ops_cl.cpl_page;
2510 pgoff_t index = osc_index(ops);
2511 struct osc_async_page *oap = &ops->ops_oap;
2512 bool unplug = false;
2516 osc_object_lock(obj);
2517 ext = osc_extent_lookup(obj, index);
2519 osc_extent_tree_dump(D_ERROR, obj);
2520 LASSERTF(0, "page index %lu is NOT covered.\n", index);
2523 switch (ext->oe_state) {
2526 CL_PAGE_DEBUG(D_ERROR, env, cp, "flush an in-rpc page?\n");
2530 /* If we know this extent is being written out, we should abort
2531 * so that the writer can make this page ready. Otherwise, there
2532 * exists a deadlock problem because other process can wait for
2533 * page writeback bit holding page lock; and meanwhile in
2534 * vvp_page_make_ready(), we need to grab page lock before
2535 * really sending the RPC. */
2537 /* race with truncate, page will be redirtied */
2539 /* The extent is active so we need to abort and let the caller
2540 * re-dirty the page. If we continued on here, and we were the
2541 * one making the extent active, we could deadlock waiting for
2542 * the page writeback to clear but it won't because the extent
2543 * is active and won't be written out. */
2544 GOTO(out, rc = -EAGAIN);
2549 rc = cl_page_prep(env, io, cp, CRT_WRITE);
2553 spin_lock(&oap->oap_lock);
2554 oap->oap_async_flags |= ASYNC_READY|ASYNC_URGENT;
2555 spin_unlock(&oap->oap_lock);
2557 if (memory_pressure_get())
2558 ext->oe_memalloc = 1;
2561 if (ext->oe_state == OES_CACHE) {
2562 OSC_EXTENT_DUMP(D_CACHE, ext,
2563 "flush page %p make it urgent.\n", oap);
2564 if (list_empty(&ext->oe_link))
2565 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2572 osc_object_unlock(obj);
2573 osc_extent_put(env, ext);
2575 osc_io_unplug_async(env, osc_cli(obj), obj);
2580 * this is called when a sync waiter receives an interruption. Its job is to
2581 * get the caller woken as soon as possible. If its page hasn't been put in an
2582 * rpc yet it can dequeue immediately. Otherwise it has to mark the rpc as
2583 * desiring interruption which will forcefully complete the rpc once the rpc
2586 int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops)
2588 struct osc_async_page *oap = &ops->ops_oap;
2589 struct osc_object *obj = oap->oap_obj;
2590 struct client_obd *cli = osc_cli(obj);
2591 struct osc_extent *ext;
2592 struct osc_extent *found = NULL;
2593 struct list_head *plist;
2594 pgoff_t index = osc_index(ops);
2599 LASSERT(!oap->oap_interrupted);
2600 oap->oap_interrupted = 1;
2602 /* Find out the caching extent */
2603 osc_object_lock(obj);
2604 if (oap->oap_cmd & OBD_BRW_WRITE) {
2605 plist = &obj->oo_urgent_exts;
2606 cmd = OBD_BRW_WRITE;
2608 plist = &obj->oo_reading_exts;
2611 list_for_each_entry(ext, plist, oe_link) {
2612 if (ext->oe_start <= index && ext->oe_end >= index) {
2613 LASSERT(ext->oe_state == OES_LOCK_DONE);
2614 /* For OES_LOCK_DONE state extent, it has already held
2615 * a refcount for RPC. */
2616 found = osc_extent_get(ext);
2620 if (found != NULL) {
2621 list_del_init(&found->oe_link);
2622 osc_update_pending(obj, cmd, -found->oe_nr_pages);
2623 osc_object_unlock(obj);
2625 osc_extent_finish(env, found, 0, -EINTR);
2626 osc_extent_put(env, found);
2629 osc_object_unlock(obj);
2630 /* ok, it's been put in an rpc. only one oap gets a request
2632 if (oap->oap_request != NULL) {
2633 ptlrpc_mark_interrupted(oap->oap_request);
2634 ptlrpcd_wake(oap->oap_request);
2635 ptlrpc_req_finished(oap->oap_request);
2636 oap->oap_request = NULL;
2640 osc_list_maint(cli, obj);
2644 int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
2645 struct list_head *list, int cmd, int brw_flags)
2647 struct client_obd *cli = osc_cli(obj);
2648 struct osc_extent *ext;
2649 struct osc_async_page *oap;
2651 int mppr = cli->cl_max_pages_per_rpc;
2652 bool can_merge = true;
2653 pgoff_t start = CL_PAGE_EOF;
2657 list_for_each_entry(oap, list, oap_pending_item) {
2658 struct osc_page *opg = oap2osc_page(oap);
2659 pgoff_t index = osc_index(opg);
2666 mppr <<= (page_count > mppr);
2668 if (unlikely(opg->ops_from > 0 || opg->ops_to < PAGE_SIZE))
2672 ext = osc_extent_alloc(obj);
2674 struct osc_async_page *tmp;
2676 list_for_each_entry_safe(oap, tmp, list, oap_pending_item) {
2677 list_del_init(&oap->oap_pending_item);
2678 osc_ap_completion(env, cli, oap, 0, -ENOMEM);
2683 ext->oe_rw = !!(cmd & OBD_BRW_READ);
2685 ext->oe_no_merge = !can_merge;
2687 ext->oe_start = start;
2688 ext->oe_end = ext->oe_max_end = end;
2690 ext->oe_srvlock = !!(brw_flags & OBD_BRW_SRVLOCK);
2691 ext->oe_nr_pages = page_count;
2692 ext->oe_mppr = mppr;
2693 list_splice_init(list, &ext->oe_pages);
2695 osc_object_lock(obj);
2696 /* Reuse the initial refcount for RPC, don't drop it */
2697 osc_extent_state_set(ext, OES_LOCK_DONE);
2698 if (cmd & OBD_BRW_WRITE) {
2699 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2700 osc_update_pending(obj, OBD_BRW_WRITE, page_count);
2702 list_add_tail(&ext->oe_link, &obj->oo_reading_exts);
2703 osc_update_pending(obj, OBD_BRW_READ, page_count);
2705 osc_object_unlock(obj);
2707 osc_io_unplug_async(env, cli, obj);
2712 * Called by osc_io_setattr_start() to freeze and destroy covering extents.
2714 int osc_cache_truncate_start(const struct lu_env *env, struct osc_object *obj,
2715 __u64 size, struct osc_extent **extp)
2717 struct client_obd *cli = osc_cli(obj);
2718 struct osc_extent *ext;
2719 struct osc_extent *waiting = NULL;
2721 struct list_head list = LIST_HEAD_INIT(list);
2726 /* pages with index greater or equal to index will be truncated. */
2727 index = cl_index(osc2cl(obj), size);
2728 partial = size > cl_offset(osc2cl(obj), index);
2731 osc_object_lock(obj);
2732 ext = osc_extent_search(obj, index);
2734 ext = first_extent(obj);
2735 else if (ext->oe_end < index)
2736 ext = next_extent(ext);
2737 while (ext != NULL) {
2738 EASSERT(ext->oe_state != OES_TRUNC, ext);
2740 if (ext->oe_state > OES_CACHE || ext->oe_urgent) {
2741 /* if ext is in urgent state, it means there must exist
2742 * a page already having been flushed by write_page().
2743 * We have to wait for this extent because we can't
2744 * truncate that page. */
2745 OSC_EXTENT_DUMP(D_CACHE, ext,
2746 "waiting for busy extent\n");
2747 waiting = osc_extent_get(ext);
2751 OSC_EXTENT_DUMP(D_CACHE, ext, "try to trunc:"LPU64".\n", size);
2753 osc_extent_get(ext);
2754 if (ext->oe_state == OES_ACTIVE) {
2755 /* though we grab inode mutex for write path, but we
2756 * release it before releasing extent(in osc_io_end()),
2757 * so there is a race window that an extent is still
2758 * in OES_ACTIVE when truncate starts. */
2759 LASSERT(!ext->oe_trunc_pending);
2760 ext->oe_trunc_pending = 1;
2762 EASSERT(ext->oe_state == OES_CACHE, ext);
2763 osc_extent_state_set(ext, OES_TRUNC);
2764 osc_update_pending(obj, OBD_BRW_WRITE,
2767 EASSERT(list_empty(&ext->oe_link), ext);
2768 list_add_tail(&ext->oe_link, &list);
2770 ext = next_extent(ext);
2772 osc_object_unlock(obj);
2774 osc_list_maint(cli, obj);
2776 while (!list_empty(&list)) {
2779 ext = list_entry(list.next, struct osc_extent, oe_link);
2780 list_del_init(&ext->oe_link);
2782 /* extent may be in OES_ACTIVE state because inode mutex
2783 * is released before osc_io_end() in file write case */
2784 if (ext->oe_state != OES_TRUNC)
2785 osc_extent_wait(env, ext, OES_TRUNC);
2787 rc = osc_extent_truncate(ext, index, partial);
2792 OSC_EXTENT_DUMP(D_ERROR, ext,
2793 "truncate error %d\n", rc);
2794 } else if (ext->oe_nr_pages == 0) {
2795 osc_extent_remove(ext);
2797 /* this must be an overlapped extent which means only
2798 * part of pages in this extent have been truncated.
2800 EASSERTF(ext->oe_start <= index, ext,
2801 "trunc index = %lu/%d.\n", index, partial);
2802 /* fix index to skip this partially truncated extent */
2803 index = ext->oe_end + 1;
2806 /* we need to hold this extent in OES_TRUNC state so
2807 * that no writeback will happen. This is to avoid
2809 * Only partial truncate can reach here, if @size is
2810 * not zero, the caller should provide a valid @extp. */
2811 LASSERT(*extp == NULL);
2812 *extp = osc_extent_get(ext);
2813 OSC_EXTENT_DUMP(D_CACHE, ext,
2814 "trunc at "LPU64"\n", size);
2816 osc_extent_put(env, ext);
2818 if (waiting != NULL) {
2821 /* ignore the result of osc_extent_wait the write initiator
2822 * should take care of it. */
2823 rc = osc_extent_wait(env, waiting, OES_INV);
2825 OSC_EXTENT_DUMP(D_CACHE, waiting, "error: %d.\n", rc);
2827 osc_extent_put(env, waiting);
2835 * Called after osc_io_setattr_end to add oio->oi_trunc back to cache.
2837 void osc_cache_truncate_end(const struct lu_env *env, struct osc_extent *ext)
2840 struct osc_object *obj = ext->oe_obj;
2841 bool unplug = false;
2843 EASSERT(ext->oe_nr_pages > 0, ext);
2844 EASSERT(ext->oe_state == OES_TRUNC, ext);
2845 EASSERT(!ext->oe_urgent, ext);
2847 OSC_EXTENT_DUMP(D_CACHE, ext, "trunc -> cache.\n");
2848 osc_object_lock(obj);
2849 osc_extent_state_set(ext, OES_CACHE);
2850 if (ext->oe_fsync_wait && !ext->oe_urgent) {
2852 list_move_tail(&ext->oe_link, &obj->oo_urgent_exts);
2855 osc_update_pending(obj, OBD_BRW_WRITE, ext->oe_nr_pages);
2856 osc_object_unlock(obj);
2857 osc_extent_put(env, ext);
2860 osc_io_unplug_async(env, osc_cli(obj), obj);
2865 * Wait for extents in a specific range to be written out.
2866 * The caller must have called osc_cache_writeback_range() to issue IO
2867 * otherwise it will take a long time for this function to finish.
2869 * Caller must hold inode_mutex , or cancel exclusive dlm lock so that
2870 * nobody else can dirty this range of file while we're waiting for
2871 * extents to be written.
2873 int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
2874 pgoff_t start, pgoff_t end)
2876 struct osc_extent *ext;
2877 pgoff_t index = start;
2882 osc_object_lock(obj);
2883 ext = osc_extent_search(obj, index);
2885 ext = first_extent(obj);
2886 else if (ext->oe_end < index)
2887 ext = next_extent(ext);
2888 while (ext != NULL) {
2891 if (ext->oe_start > end)
2894 if (!ext->oe_fsync_wait) {
2895 ext = next_extent(ext);
2899 EASSERT(ergo(ext->oe_state == OES_CACHE,
2900 ext->oe_hp || ext->oe_urgent), ext);
2901 EASSERT(ergo(ext->oe_state == OES_ACTIVE,
2902 !ext->oe_hp && ext->oe_urgent), ext);
2904 index = ext->oe_end + 1;
2905 osc_extent_get(ext);
2906 osc_object_unlock(obj);
2908 rc = osc_extent_wait(env, ext, OES_INV);
2911 osc_extent_put(env, ext);
2914 osc_object_unlock(obj);
2916 OSC_IO_DEBUG(obj, "sync file range.\n");
2921 * Called to write out a range of osc object.
2923 * @hp : should be set this is caused by lock cancel;
2924 * @discard: is set if dirty pages should be dropped - file will be deleted or
2925 * truncated, this implies there is no partially discarding extents.
2927 * Return how many pages will be issued, or error code if error occurred.
2929 int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
2930 pgoff_t start, pgoff_t end, int hp, int discard)
2932 struct osc_extent *ext;
2933 struct list_head discard_list = LIST_HEAD_INIT(discard_list);
2934 bool unplug = false;
2938 osc_object_lock(obj);
2939 ext = osc_extent_search(obj, start);
2941 ext = first_extent(obj);
2942 else if (ext->oe_end < start)
2943 ext = next_extent(ext);
2944 while (ext != NULL) {
2945 if (ext->oe_start > end)
2948 ext->oe_fsync_wait = 1;
2949 switch (ext->oe_state) {
2951 result += ext->oe_nr_pages;
2953 struct list_head *list = NULL;
2955 EASSERT(!ext->oe_hp, ext);
2957 list = &obj->oo_hp_exts;
2958 } else if (!ext->oe_urgent) {
2960 list = &obj->oo_urgent_exts;
2963 list_move_tail(&ext->oe_link, list);
2966 /* the only discarder is lock cancelling, so
2967 * [start, end] must contain this extent */
2968 EASSERT(ext->oe_start >= start &&
2969 ext->oe_max_end <= end, ext);
2970 osc_extent_state_set(ext, OES_LOCKING);
2971 ext->oe_owner = current;
2972 list_move_tail(&ext->oe_link,
2974 osc_update_pending(obj, OBD_BRW_WRITE,
2979 /* It's pretty bad to wait for ACTIVE extents, because
2980 * we don't know how long we will wait for it to be
2981 * flushed since it may be blocked at awaiting more
2982 * grants. We do this for the correctness of fsync. */
2983 LASSERT(hp == 0 && discard == 0);
2987 /* this extent is being truncated, can't do anything
2988 * for it now. it will be set to urgent after truncate
2989 * is finished in osc_cache_truncate_end(). */
2993 ext = next_extent(ext);
2995 osc_object_unlock(obj);
2997 LASSERT(ergo(!discard, list_empty(&discard_list)));
2998 if (!list_empty(&discard_list)) {
2999 struct osc_extent *tmp;
3002 osc_list_maint(osc_cli(obj), obj);
3003 list_for_each_entry_safe(ext, tmp, &discard_list, oe_link) {
3004 list_del_init(&ext->oe_link);
3005 EASSERT(ext->oe_state == OES_LOCKING, ext);
3007 /* Discard caching pages. We don't actually write this
3008 * extent out but we complete it as if we did. */
3009 rc = osc_extent_make_ready(env, ext);
3010 if (unlikely(rc < 0)) {
3011 OSC_EXTENT_DUMP(D_ERROR, ext,
3012 "make_ready returned %d\n", rc);
3017 /* finish the extent as if the pages were sent */
3018 osc_extent_finish(env, ext, 0, 0);
3023 osc_io_unplug(env, osc_cli(obj), obj);
3025 if (hp || discard) {
3027 rc = osc_cache_wait_range(env, obj, start, end);
3028 if (result >= 0 && rc < 0)
3032 OSC_IO_DEBUG(obj, "pageout [%lu, %lu], %d.\n", start, end, result);
3037 * Returns a list of pages by a given [start, end] of \a obj.
3039 * \param resched If not NULL, then we give up before hogging CPU for too
3040 * long and set *resched = 1, in that case caller should implement a retry
3043 * Gang tree lookup (radix_tree_gang_lookup()) optimization is absolutely
3044 * crucial in the face of [offset, EOF] locks.
3046 * Return at least one page in @queue unless there is no covered page.
3048 int osc_page_gang_lookup(const struct lu_env *env, struct cl_io *io,
3049 struct osc_object *osc, pgoff_t start, pgoff_t end,
3050 osc_page_gang_cbt cb, void *cbdata)
3052 struct osc_page *ops;
3058 int res = CLP_GANG_OKAY;
3059 bool tree_lock = true;
3063 pvec = osc_env_info(env)->oti_pvec;
3064 spin_lock(&osc->oo_tree_lock);
3065 while ((nr = radix_tree_gang_lookup(&osc->oo_tree, pvec,
3066 idx, OTI_PVEC_SIZE)) > 0) {
3067 struct cl_page *page;
3068 bool end_of_region = false;
3070 for (i = 0, j = 0; i < nr; ++i) {
3074 idx = osc_index(ops);
3076 end_of_region = true;
3080 page = ops->ops_cl.cpl_page;
3081 LASSERT(page->cp_type == CPT_CACHEABLE);
3082 if (page->cp_state == CPS_FREEING)
3086 lu_ref_add_atomic(&page->cp_reference,
3087 "gang_lookup", current);
3093 * Here a delicate locking dance is performed. Current thread
3094 * holds a reference to a page, but has to own it before it
3095 * can be placed into queue. Owning implies waiting, so
3096 * radix-tree lock is to be released. After a wait one has to
3097 * check that pages weren't truncated (cl_page_own() returns
3098 * error in the latter case).
3100 spin_unlock(&osc->oo_tree_lock);
3103 for (i = 0; i < j; ++i) {
3105 if (res == CLP_GANG_OKAY)
3106 res = (*cb)(env, io, ops, cbdata);
3108 page = ops->ops_cl.cpl_page;
3109 lu_ref_del(&page->cp_reference, "gang_lookup", current);
3110 cl_page_put(env, page);
3112 if (nr < OTI_PVEC_SIZE || end_of_region)
3115 if (res == CLP_GANG_OKAY && need_resched())
3116 res = CLP_GANG_RESCHED;
3117 if (res != CLP_GANG_OKAY)
3120 spin_lock(&osc->oo_tree_lock);
3124 spin_unlock(&osc->oo_tree_lock);
3129 * Check if page @page is covered by an extra lock or discard it.
3131 static int check_and_discard_cb(const struct lu_env *env, struct cl_io *io,
3132 struct osc_page *ops, void *cbdata)
3134 struct osc_thread_info *info = osc_env_info(env);
3135 struct osc_object *osc = cbdata;
3138 index = osc_index(ops);
3139 if (index >= info->oti_fn_index) {
3140 struct ldlm_lock *tmp;
3141 struct cl_page *page = ops->ops_cl.cpl_page;
3143 /* refresh non-overlapped index */
3144 tmp = osc_dlmlock_at_pgoff(env, osc, index,
3145 OSC_DAP_FL_TEST_LOCK);
3147 __u64 end = tmp->l_policy_data.l_extent.end;
3148 /* Cache the first-non-overlapped index so as to skip
3149 * all pages within [index, oti_fn_index). This is safe
3150 * because if tmp lock is canceled, it will discard
3152 info->oti_fn_index = cl_index(osc2cl(osc), end + 1);
3153 if (end == OBD_OBJECT_EOF)
3154 info->oti_fn_index = CL_PAGE_EOF;
3156 } else if (cl_page_own(env, io, page) == 0) {
3157 /* discard the page */
3158 cl_page_discard(env, io, page);
3159 cl_page_disown(env, io, page);
3161 LASSERT(page->cp_state == CPS_FREEING);
3165 info->oti_next_index = index + 1;
3166 return CLP_GANG_OKAY;
3169 static int discard_cb(const struct lu_env *env, struct cl_io *io,
3170 struct osc_page *ops, void *cbdata)
3172 struct osc_thread_info *info = osc_env_info(env);
3173 struct cl_page *page = ops->ops_cl.cpl_page;
3175 /* page is top page. */
3176 info->oti_next_index = osc_index(ops) + 1;
3177 if (cl_page_own(env, io, page) == 0) {
3178 if (!ergo(page->cp_type == CPT_CACHEABLE,
3179 !PageDirty(cl_page_vmpage(page))))
3180 CL_PAGE_DEBUG(D_ERROR, env, page,
3181 "discard dirty page?\n");
3183 /* discard the page */
3184 cl_page_discard(env, io, page);
3185 cl_page_disown(env, io, page);
3187 LASSERT(page->cp_state == CPS_FREEING);
3190 return CLP_GANG_OKAY;
3194 * Discard pages protected by the given lock. This function traverses radix
3195 * tree to find all covering pages and discard them. If a page is being covered
3196 * by other locks, it should remain in cache.
3198 * If error happens on any step, the process continues anyway (the reasoning
3199 * behind this being that lock cancellation cannot be delayed indefinitely).
3201 int osc_lock_discard_pages(const struct lu_env *env, struct osc_object *osc,
3202 pgoff_t start, pgoff_t end, enum cl_lock_mode mode)
3204 struct osc_thread_info *info = osc_env_info(env);
3205 struct cl_io *io = &info->oti_io;
3206 osc_page_gang_cbt cb;
3212 io->ci_obj = cl_object_top(osc2cl(osc));
3213 io->ci_ignore_layout = 1;
3214 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
3218 cb = mode == CLM_READ ? check_and_discard_cb : discard_cb;
3219 info->oti_fn_index = info->oti_next_index = start;
3221 res = osc_page_gang_lookup(env, io, osc,
3222 info->oti_next_index, end, cb, osc);
3223 if (info->oti_next_index > end)
3226 if (res == CLP_GANG_RESCHED)
3228 } while (res != CLP_GANG_OKAY);
3230 cl_io_fini(env, io);