4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
26 * Copyright (c) 2012, 2016, Intel Corporation.
30 * This file is part of Lustre, http://www.lustre.org/
31 * Lustre is a trademark of Sun Microsystems, Inc.
33 * osc cache management.
35 * Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
38 #define DEBUG_SUBSYSTEM S_OSC
40 #include <lustre_osc.h>
42 #include "osc_internal.h"
44 static int extent_debug; /* set it to be true for more debug */
46 static void osc_update_pending(struct osc_object *obj, int cmd, int delta);
47 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
48 enum osc_extent_state state);
49 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
50 struct osc_async_page *oap, int sent, int rc);
51 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
53 static int osc_refresh_count(const struct lu_env *env,
54 struct osc_async_page *oap, int cmd);
55 static int osc_io_unplug_async(const struct lu_env *env,
56 struct client_obd *cli, struct osc_object *osc);
57 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
58 unsigned int lost_grant, unsigned int dirty_grant);
60 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
61 const char *func, int line);
62 #define osc_extent_tree_dump(lvl, obj) \
63 osc_extent_tree_dump0(lvl, obj, __func__, __LINE__)
65 static void osc_unreserve_grant(struct client_obd *cli, unsigned int reserved,
72 /* ------------------ osc extent ------------------ */
73 static inline char *ext_flags(struct osc_extent *ext, char *flags)
76 *buf++ = ext->oe_rw ? 'r' : 'w';
89 if (ext->oe_trunc_pending)
91 if (ext->oe_fsync_wait)
97 static inline char list_empty_marker(struct list_head *list)
99 return list_empty(list) ? '-' : '+';
102 #define EXTSTR "[%lu -> %lu/%lu]"
103 #define EXTPARA(ext) (ext)->oe_start, (ext)->oe_end, (ext)->oe_max_end
104 static const char *oes_strings[] = {
105 "inv", "active", "cache", "locking", "lockdone", "rpc", "trunc", NULL };
107 #define OSC_EXTENT_DUMP(lvl, extent, fmt, ...) do { \
108 struct osc_extent *__ext = (extent); \
112 "extent %p@{" EXTSTR ", " \
113 "[%d|%d|%c|%s|%s|%p], [%d|%d|%c|%c|%p|%u|%p]} " fmt, \
114 /* ----- extent part 0 ----- */ \
115 __ext, EXTPARA(__ext), \
116 /* ----- part 1 ----- */ \
117 atomic_read(&__ext->oe_refc), \
118 atomic_read(&__ext->oe_users), \
119 list_empty_marker(&__ext->oe_link), \
120 oes_strings[__ext->oe_state], ext_flags(__ext, __buf), \
122 /* ----- part 2 ----- */ \
123 __ext->oe_grants, __ext->oe_nr_pages, \
124 list_empty_marker(&__ext->oe_pages), \
125 waitqueue_active(&__ext->oe_waitq) ? '+' : '-', \
126 __ext->oe_dlmlock, __ext->oe_mppr, __ext->oe_owner, \
127 /* ----- part 4 ----- */ \
129 if (lvl == D_ERROR && __ext->oe_dlmlock != NULL) \
130 LDLM_ERROR(__ext->oe_dlmlock, "extent: %p", __ext); \
132 LDLM_DEBUG(__ext->oe_dlmlock, "extent: %p", __ext); \
136 #define EASSERTF(expr, ext, fmt, args...) do { \
138 OSC_EXTENT_DUMP(D_ERROR, (ext), fmt, ##args); \
139 osc_extent_tree_dump(D_ERROR, (ext)->oe_obj); \
145 #define EASSERT(expr, ext) EASSERTF(expr, ext, "\n")
147 static inline struct osc_extent *rb_extent(struct rb_node *n)
152 return container_of(n, struct osc_extent, oe_node);
155 static inline struct osc_extent *next_extent(struct osc_extent *ext)
160 LASSERT(ext->oe_intree);
161 return rb_extent(rb_next(&ext->oe_node));
164 static inline struct osc_extent *prev_extent(struct osc_extent *ext)
169 LASSERT(ext->oe_intree);
170 return rb_extent(rb_prev(&ext->oe_node));
173 static inline struct osc_extent *first_extent(struct osc_object *obj)
175 return rb_extent(rb_first(&obj->oo_root));
178 /* object must be locked by caller. */
179 static int osc_extent_sanity_check0(struct osc_extent *ext,
180 const char *func, const int line)
182 struct osc_object *obj = ext->oe_obj;
183 struct osc_async_page *oap;
187 if (!osc_object_is_locked(obj))
190 if (ext->oe_state >= OES_STATE_MAX)
193 if (atomic_read(&ext->oe_refc) <= 0)
196 if (atomic_read(&ext->oe_refc) < atomic_read(&ext->oe_users))
199 switch (ext->oe_state) {
201 if (ext->oe_nr_pages > 0 || !list_empty(&ext->oe_pages))
206 if (atomic_read(&ext->oe_users) == 0)
210 if (ext->oe_fsync_wait && !ext->oe_urgent)
214 if (ext->oe_grants == 0)
216 if (ext->oe_fsync_wait && !ext->oe_urgent && !ext->oe_hp)
219 if (atomic_read(&ext->oe_users) > 0)
223 if (ext->oe_max_end < ext->oe_end || ext->oe_end < ext->oe_start)
226 if (ext->oe_sync && ext->oe_grants > 0)
229 if (ext->oe_dlmlock != NULL &&
230 ext->oe_dlmlock->l_resource->lr_type == LDLM_EXTENT &&
231 !ldlm_is_failed(ext->oe_dlmlock)) {
232 struct ldlm_extent *extent;
234 extent = &ext->oe_dlmlock->l_policy_data.l_extent;
235 if (!(extent->start <= cl_offset(osc2cl(obj), ext->oe_start) &&
236 extent->end >= cl_offset(osc2cl(obj), ext->oe_max_end)))
239 if (!(ext->oe_dlmlock->l_granted_mode & (LCK_PW | LCK_GROUP)))
243 if (ext->oe_nr_pages > ext->oe_mppr)
246 /* Do not verify page list if extent is in RPC. This is because an
247 * in-RPC extent is supposed to be exclusively accessible w/o lock. */
248 if (ext->oe_state > OES_CACHE)
255 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
256 pgoff_t index = osc_index(oap2osc(oap));
258 if (index > ext->oe_end || index < ext->oe_start)
261 if (page_count != ext->oe_nr_pages)
266 OSC_EXTENT_DUMP(D_ERROR, ext,
267 "%s:%d sanity check %p failed with rc = %d\n",
268 func, line, ext, rc);
272 #define sanity_check_nolock(ext) \
273 osc_extent_sanity_check0(ext, __func__, __LINE__)
275 #define sanity_check(ext) ({ \
277 osc_object_lock((ext)->oe_obj); \
278 __res = sanity_check_nolock(ext); \
279 osc_object_unlock((ext)->oe_obj); \
285 * sanity check - to make sure there is no overlapped extent in the tree.
287 static int osc_extent_is_overlapped(struct osc_object *obj,
288 struct osc_extent *ext)
290 struct osc_extent *tmp;
292 LASSERT(osc_object_is_locked(obj));
297 for (tmp = first_extent(obj); tmp != NULL; tmp = next_extent(tmp)) {
300 if (tmp->oe_end >= ext->oe_start &&
301 tmp->oe_start <= ext->oe_end)
307 static void osc_extent_state_set(struct osc_extent *ext, int state)
309 LASSERT(osc_object_is_locked(ext->oe_obj));
310 LASSERT(state >= OES_INV && state < OES_STATE_MAX);
312 /* Never try to sanity check a state changing extent :-) */
313 /* LASSERT(sanity_check_nolock(ext) == 0); */
315 /* TODO: validate the state machine */
316 ext->oe_state = state;
317 wake_up_all(&ext->oe_waitq);
320 static struct osc_extent *osc_extent_alloc(struct osc_object *obj)
322 struct osc_extent *ext;
324 OBD_SLAB_ALLOC_PTR_GFP(ext, osc_extent_kmem, GFP_NOFS);
328 RB_CLEAR_NODE(&ext->oe_node);
330 cl_object_get(osc2cl(obj));
331 atomic_set(&ext->oe_refc, 1);
332 atomic_set(&ext->oe_users, 0);
333 INIT_LIST_HEAD(&ext->oe_link);
334 ext->oe_state = OES_INV;
335 INIT_LIST_HEAD(&ext->oe_pages);
336 init_waitqueue_head(&ext->oe_waitq);
337 ext->oe_dlmlock = NULL;
342 static void osc_extent_free(struct osc_extent *ext)
344 OBD_SLAB_FREE_PTR(ext, osc_extent_kmem);
347 static struct osc_extent *osc_extent_get(struct osc_extent *ext)
349 LASSERT(atomic_read(&ext->oe_refc) >= 0);
350 atomic_inc(&ext->oe_refc);
354 static void osc_extent_put(const struct lu_env *env, struct osc_extent *ext)
356 LASSERT(atomic_read(&ext->oe_refc) > 0);
357 if (atomic_dec_and_test(&ext->oe_refc)) {
358 LASSERT(list_empty(&ext->oe_link));
359 LASSERT(atomic_read(&ext->oe_users) == 0);
360 LASSERT(ext->oe_state == OES_INV);
361 LASSERT(!ext->oe_intree);
363 if (ext->oe_dlmlock != NULL) {
364 lu_ref_add(&ext->oe_dlmlock->l_reference,
366 LDLM_LOCK_PUT(ext->oe_dlmlock);
367 ext->oe_dlmlock = NULL;
369 cl_object_put(env, osc2cl(ext->oe_obj));
370 osc_extent_free(ext);
375 * osc_extent_put_trust() is a special version of osc_extent_put() when
376 * it's known that the caller is not the last user. This is to address the
377 * problem of lacking of lu_env ;-).
379 static void osc_extent_put_trust(struct osc_extent *ext)
381 LASSERT(atomic_read(&ext->oe_refc) > 1);
382 LASSERT(osc_object_is_locked(ext->oe_obj));
383 atomic_dec(&ext->oe_refc);
387 * Return the extent which includes pgoff @index, or return the greatest
388 * previous extent in the tree.
390 static struct osc_extent *osc_extent_search(struct osc_object *obj,
393 struct rb_node *n = obj->oo_root.rb_node;
394 struct osc_extent *tmp, *p = NULL;
396 LASSERT(osc_object_is_locked(obj));
399 if (index < tmp->oe_start) {
401 } else if (index > tmp->oe_end) {
412 * Return the extent covering @index, otherwise return NULL.
413 * caller must have held object lock.
415 static struct osc_extent *osc_extent_lookup(struct osc_object *obj,
418 struct osc_extent *ext;
420 ext = osc_extent_search(obj, index);
421 if (ext != NULL && ext->oe_start <= index && index <= ext->oe_end)
422 return osc_extent_get(ext);
426 /* caller must have held object lock. */
427 static void osc_extent_insert(struct osc_object *obj, struct osc_extent *ext)
429 struct rb_node **n = &obj->oo_root.rb_node;
430 struct rb_node *parent = NULL;
431 struct osc_extent *tmp;
433 LASSERT(ext->oe_intree == 0);
434 LASSERT(ext->oe_obj == obj);
435 LASSERT(osc_object_is_locked(obj));
440 if (ext->oe_end < tmp->oe_start)
442 else if (ext->oe_start > tmp->oe_end)
445 EASSERTF(0, tmp, EXTSTR"\n", EXTPARA(ext));
447 rb_link_node(&ext->oe_node, parent, n);
448 rb_insert_color(&ext->oe_node, &obj->oo_root);
453 /* caller must have held object lock. */
454 static void osc_extent_erase(struct osc_extent *ext)
456 struct osc_object *obj = ext->oe_obj;
457 LASSERT(osc_object_is_locked(obj));
458 if (ext->oe_intree) {
459 rb_erase(&ext->oe_node, &obj->oo_root);
461 /* rbtree held a refcount */
462 osc_extent_put_trust(ext);
466 static struct osc_extent *osc_extent_hold(struct osc_extent *ext)
468 struct osc_object *obj = ext->oe_obj;
470 LASSERT(osc_object_is_locked(obj));
471 LASSERT(ext->oe_state == OES_ACTIVE || ext->oe_state == OES_CACHE);
472 if (ext->oe_state == OES_CACHE) {
473 osc_extent_state_set(ext, OES_ACTIVE);
474 osc_update_pending(obj, OBD_BRW_WRITE, -ext->oe_nr_pages);
476 atomic_inc(&ext->oe_users);
477 list_del_init(&ext->oe_link);
478 return osc_extent_get(ext);
481 static void __osc_extent_remove(struct osc_extent *ext)
483 LASSERT(osc_object_is_locked(ext->oe_obj));
484 LASSERT(list_empty(&ext->oe_pages));
485 osc_extent_erase(ext);
486 list_del_init(&ext->oe_link);
487 osc_extent_state_set(ext, OES_INV);
488 OSC_EXTENT_DUMP(D_CACHE, ext, "destroyed.\n");
491 static void osc_extent_remove(struct osc_extent *ext)
493 struct osc_object *obj = ext->oe_obj;
495 osc_object_lock(obj);
496 __osc_extent_remove(ext);
497 osc_object_unlock(obj);
501 * This function is used to merge extents to get better performance. It checks
502 * if @cur and @victim are contiguous at block level.
504 static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
505 struct osc_extent *victim)
507 struct osc_object *obj = cur->oe_obj;
508 struct client_obd *cli = osc_cli(obj);
513 LASSERT(cur->oe_state == OES_CACHE);
514 LASSERT(osc_object_is_locked(obj));
518 if (victim->oe_state != OES_CACHE || victim->oe_fsync_wait)
521 if (cur->oe_max_end != victim->oe_max_end)
524 LASSERT(cur->oe_dlmlock == victim->oe_dlmlock);
525 ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_SHIFT;
526 chunk_start = cur->oe_start >> ppc_bits;
527 chunk_end = cur->oe_end >> ppc_bits;
528 if (chunk_start != (victim->oe_end >> ppc_bits) + 1 &&
529 chunk_end + 1 != victim->oe_start >> ppc_bits)
532 /* overall extent size should not exceed the max supported limit
533 * reported by the server */
534 if (cur->oe_end - cur->oe_start + 1 +
535 victim->oe_end - victim->oe_start + 1 > cli->cl_max_extent_pages)
538 OSC_EXTENT_DUMP(D_CACHE, victim, "will be merged by %p.\n", cur);
540 cur->oe_start = min(cur->oe_start, victim->oe_start);
541 cur->oe_end = max(cur->oe_end, victim->oe_end);
542 /* per-extent tax should be accounted only once for the whole extent */
543 cur->oe_grants += victim->oe_grants - cli->cl_grant_extent_tax;
544 cur->oe_nr_pages += victim->oe_nr_pages;
545 /* only the following bits are needed to merge */
546 cur->oe_urgent |= victim->oe_urgent;
547 cur->oe_memalloc |= victim->oe_memalloc;
548 list_splice_init(&victim->oe_pages, &cur->oe_pages);
549 list_del_init(&victim->oe_link);
550 victim->oe_nr_pages = 0;
552 osc_extent_get(victim);
553 __osc_extent_remove(victim);
554 osc_extent_put(env, victim);
556 OSC_EXTENT_DUMP(D_CACHE, cur, "after merging %p.\n", victim);
561 * Drop user count of osc_extent, and unplug IO asynchronously.
563 int osc_extent_release(const struct lu_env *env, struct osc_extent *ext)
565 struct osc_object *obj = ext->oe_obj;
566 struct client_obd *cli = osc_cli(obj);
570 LASSERT(atomic_read(&ext->oe_users) > 0);
571 LASSERT(sanity_check(ext) == 0);
572 LASSERT(ext->oe_grants > 0);
574 if (atomic_dec_and_lock(&ext->oe_users, &obj->oo_lock)) {
575 LASSERT(ext->oe_state == OES_ACTIVE);
576 if (ext->oe_trunc_pending) {
577 /* a truncate process is waiting for this extent.
578 * This may happen due to a race, check
579 * osc_cache_truncate_start(). */
580 osc_extent_state_set(ext, OES_TRUNC);
581 ext->oe_trunc_pending = 0;
585 osc_extent_state_set(ext, OES_CACHE);
586 osc_update_pending(obj, OBD_BRW_WRITE,
589 /* try to merge the previous and next extent. */
590 if (osc_extent_merge(env, ext, prev_extent(ext)) == 0)
591 grant += cli->cl_grant_extent_tax;
592 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
593 grant += cli->cl_grant_extent_tax;
595 osc_unreserve_grant(cli, 0, grant);
598 list_move_tail(&ext->oe_link,
599 &obj->oo_urgent_exts);
600 else if (ext->oe_nr_pages == ext->oe_mppr) {
601 list_move_tail(&ext->oe_link,
605 osc_object_unlock(obj);
607 osc_io_unplug_async(env, cli, obj);
609 osc_extent_put(env, ext);
613 static inline int overlapped(struct osc_extent *ex1, struct osc_extent *ex2)
615 return !(ex1->oe_end < ex2->oe_start || ex2->oe_end < ex1->oe_start);
619 * Find or create an extent which includes @index, core function to manage
622 static struct osc_extent *osc_extent_find(const struct lu_env *env,
623 struct osc_object *obj, pgoff_t index,
624 unsigned int *grants)
626 struct client_obd *cli = osc_cli(obj);
627 struct osc_lock *olck;
628 struct cl_lock_descr *descr;
629 struct osc_extent *cur;
630 struct osc_extent *ext;
631 struct osc_extent *conflict = NULL;
632 struct osc_extent *found = NULL;
635 unsigned int max_pages; /* max_pages_per_rpc */
636 unsigned int chunksize;
637 int ppc_bits; /* pages per chunk bits */
642 cur = osc_extent_alloc(obj);
644 RETURN(ERR_PTR(-ENOMEM));
646 olck = osc_env_io(env)->oi_write_osclock;
647 LASSERTF(olck != NULL, "page %lu is not covered by lock\n", index);
648 LASSERT(olck->ols_state == OLS_GRANTED);
650 descr = &olck->ols_cl.cls_lock->cll_descr;
651 LASSERT(descr->cld_mode >= CLM_WRITE);
653 LASSERTF(cli->cl_chunkbits >= PAGE_SHIFT,
654 "chunkbits: %u\n", cli->cl_chunkbits);
655 ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
656 chunk_mask = ~((1 << ppc_bits) - 1);
657 chunksize = 1 << cli->cl_chunkbits;
658 chunk = index >> ppc_bits;
660 /* align end to RPC edge. */
661 max_pages = cli->cl_max_pages_per_rpc;
662 if ((max_pages & ~chunk_mask) != 0) {
663 CERROR("max_pages: %#x chunkbits: %u chunk_mask: %#lx\n",
664 max_pages, cli->cl_chunkbits, chunk_mask);
665 RETURN(ERR_PTR(-EINVAL));
667 max_end = index - (index % max_pages) + max_pages - 1;
668 max_end = min_t(pgoff_t, max_end, descr->cld_end);
670 /* initialize new extent by parameters so far */
671 cur->oe_max_end = max_end;
672 cur->oe_start = index & chunk_mask;
673 cur->oe_end = ((index + ~chunk_mask + 1) & chunk_mask) - 1;
674 if (cur->oe_start < descr->cld_start)
675 cur->oe_start = descr->cld_start;
676 if (cur->oe_end > max_end)
677 cur->oe_end = max_end;
679 cur->oe_mppr = max_pages;
680 if (olck->ols_dlmlock != NULL) {
681 LASSERT(olck->ols_hold);
682 cur->oe_dlmlock = LDLM_LOCK_GET(olck->ols_dlmlock);
683 lu_ref_add(&olck->ols_dlmlock->l_reference, "osc_extent", cur);
686 /* grants has been allocated by caller */
687 LASSERTF(*grants >= chunksize + cli->cl_grant_extent_tax,
688 "%u/%u/%u.\n", *grants, chunksize, cli->cl_grant_extent_tax);
689 LASSERTF((max_end - cur->oe_start) < max_pages, EXTSTR"\n",
693 osc_object_lock(obj);
694 ext = osc_extent_search(obj, cur->oe_start);
696 ext = first_extent(obj);
697 while (ext != NULL) {
698 pgoff_t ext_chk_start = ext->oe_start >> ppc_bits;
699 pgoff_t ext_chk_end = ext->oe_end >> ppc_bits;
701 LASSERT(sanity_check_nolock(ext) == 0);
702 if (chunk > ext_chk_end + 1)
705 /* if covering by different locks, no chance to match */
706 if (olck->ols_dlmlock != ext->oe_dlmlock) {
707 EASSERTF(!overlapped(ext, cur), ext,
708 EXTSTR"\n", EXTPARA(cur));
710 ext = next_extent(ext);
714 /* discontiguous chunks? */
715 if (chunk + 1 < ext_chk_start) {
716 ext = next_extent(ext);
720 /* ok, from now on, ext and cur have these attrs:
721 * 1. covered by the same lock
722 * 2. contiguous at chunk level or overlapping. */
724 if (overlapped(ext, cur)) {
725 /* cur is the minimum unit, so overlapping means
727 EASSERTF((ext->oe_start <= cur->oe_start &&
728 ext->oe_end >= cur->oe_end),
729 ext, EXTSTR"\n", EXTPARA(cur));
731 if (ext->oe_state > OES_CACHE || ext->oe_fsync_wait) {
732 /* for simplicity, we wait for this extent to
733 * finish before going forward. */
734 conflict = osc_extent_get(ext);
738 found = osc_extent_hold(ext);
742 /* non-overlapped extent */
743 if (ext->oe_state != OES_CACHE || ext->oe_fsync_wait) {
744 /* we can't do anything for a non OES_CACHE extent, or
745 * if there is someone waiting for this extent to be
746 * flushed, try next one. */
747 ext = next_extent(ext);
751 /* check if they belong to the same rpc slot before trying to
752 * merge. the extents are not overlapped and contiguous at
753 * chunk level to get here. */
754 if (ext->oe_max_end != max_end) {
755 /* if they don't belong to the same RPC slot or
756 * max_pages_per_rpc has ever changed, do not merge. */
757 ext = next_extent(ext);
761 /* check whether maximum extent size will be hit */
762 if ((ext_chk_end - ext_chk_start + 1 + 1) << ppc_bits >
763 cli->cl_max_extent_pages) {
764 ext = next_extent(ext);
768 /* it's required that an extent must be contiguous at chunk
769 * level so that we know the whole extent is covered by grant
770 * (the pages in the extent are NOT required to be contiguous).
771 * Otherwise, it will be too much difficult to know which
772 * chunks have grants allocated. */
774 /* try to do front merge - extend ext's start */
775 if (chunk + 1 == ext_chk_start) {
776 /* ext must be chunk size aligned */
777 EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
779 /* pull ext's start back to cover cur */
780 ext->oe_start = cur->oe_start;
781 ext->oe_grants += chunksize;
782 LASSERT(*grants >= chunksize);
783 *grants -= chunksize;
785 found = osc_extent_hold(ext);
786 } else if (chunk == ext_chk_end + 1) {
788 ext->oe_end = cur->oe_end;
789 ext->oe_grants += chunksize;
790 LASSERT(*grants >= chunksize);
791 *grants -= chunksize;
793 /* try to merge with the next one because we just fill
795 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
796 /* we can save extent tax from next extent */
797 *grants += cli->cl_grant_extent_tax;
799 found = osc_extent_hold(ext);
804 ext = next_extent(ext);
807 osc_extent_tree_dump(D_CACHE, obj);
809 LASSERT(conflict == NULL);
810 if (!IS_ERR(found)) {
811 LASSERT(found->oe_dlmlock == cur->oe_dlmlock);
812 OSC_EXTENT_DUMP(D_CACHE, found,
813 "found caching ext for %lu.\n", index);
815 } else if (conflict == NULL) {
816 /* create a new extent */
817 EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
818 cur->oe_grants = chunksize + cli->cl_grant_extent_tax;
819 LASSERT(*grants >= cur->oe_grants);
820 *grants -= cur->oe_grants;
822 cur->oe_state = OES_CACHE;
823 found = osc_extent_hold(cur);
824 osc_extent_insert(obj, cur);
825 OSC_EXTENT_DUMP(D_CACHE, cur, "add into tree %lu/%lu.\n",
826 index, descr->cld_end);
828 osc_object_unlock(obj);
830 if (conflict != NULL) {
831 LASSERT(found == NULL);
833 /* waiting for IO to finish. Please notice that it's impossible
834 * to be an OES_TRUNC extent. */
835 rc = osc_extent_wait(env, conflict, OES_INV);
836 osc_extent_put(env, conflict);
839 GOTO(out, found = ERR_PTR(rc));
846 osc_extent_put(env, cur);
851 * Called when IO is finished to an extent.
853 int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
856 struct client_obd *cli = osc_cli(ext->oe_obj);
857 struct osc_async_page *oap;
858 struct osc_async_page *tmp;
859 int nr_pages = ext->oe_nr_pages;
861 int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
866 OSC_EXTENT_DUMP(D_CACHE, ext, "extent finished.\n");
868 ext->oe_rc = rc ?: ext->oe_nr_pages;
869 EASSERT(ergo(rc == 0, ext->oe_state == OES_RPC), ext);
871 osc_lru_add_batch(cli, &ext->oe_pages);
872 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
874 list_del_init(&oap->oap_rpc_item);
875 list_del_init(&oap->oap_pending_item);
876 if (last_off <= oap->oap_obj_off) {
877 last_off = oap->oap_obj_off;
878 last_count = oap->oap_count;
882 osc_ap_completion(env, cli, oap, sent, rc);
884 EASSERT(ext->oe_nr_pages == 0, ext);
887 lost_grant = ext->oe_grants;
888 } else if (blocksize < PAGE_SIZE &&
889 last_count != PAGE_SIZE) {
890 /* For short writes we shouldn't count parts of pages that
891 * span a whole chunk on the OST side, or our accounting goes
892 * wrong. Should match the code in filter_grant_check. */
893 int offset = last_off & ~PAGE_MASK;
894 int count = last_count + (offset & (blocksize - 1));
895 int end = (offset + last_count) & (blocksize - 1);
897 count += blocksize - end;
899 lost_grant = PAGE_SIZE - count;
901 if (ext->oe_grants > 0)
902 osc_free_grant(cli, nr_pages, lost_grant, ext->oe_grants);
904 osc_extent_remove(ext);
905 /* put the refcount for RPC */
906 osc_extent_put(env, ext);
910 static int extent_wait_cb(struct osc_extent *ext, enum osc_extent_state state)
914 osc_object_lock(ext->oe_obj);
915 ret = ext->oe_state == state;
916 osc_object_unlock(ext->oe_obj);
922 * Wait for the extent's state to become @state.
924 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
925 enum osc_extent_state state)
927 struct osc_object *obj = ext->oe_obj;
928 struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(600), NULL,
929 LWI_ON_SIGNAL_NOOP, NULL);
933 osc_object_lock(obj);
934 LASSERT(sanity_check_nolock(ext) == 0);
935 /* `Kick' this extent only if the caller is waiting for it to be
937 if (state == OES_INV && !ext->oe_urgent && !ext->oe_hp) {
938 if (ext->oe_state == OES_ACTIVE) {
940 } else if (ext->oe_state == OES_CACHE) {
942 osc_extent_hold(ext);
946 osc_object_unlock(obj);
948 osc_extent_release(env, ext);
950 /* wait for the extent until its state becomes @state */
951 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state), &lwi);
952 if (rc == -ETIMEDOUT) {
953 OSC_EXTENT_DUMP(D_ERROR, ext,
954 "%s: wait ext to %u timedout, recovery in progress?\n",
955 cli_name(osc_cli(obj)), state);
957 lwi = LWI_INTR(NULL, NULL);
958 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state),
961 if (rc == 0 && ext->oe_rc < 0)
967 * Discard pages with index greater than @size. If @ext is overlapped with
968 * @size, then partial truncate happens.
970 static int osc_extent_truncate(struct osc_extent *ext, pgoff_t trunc_index,
975 struct osc_object *obj = ext->oe_obj;
976 struct client_obd *cli = osc_cli(obj);
977 struct osc_async_page *oap;
978 struct osc_async_page *tmp;
979 int pages_in_chunk = 0;
980 int ppc_bits = cli->cl_chunkbits -
982 __u64 trunc_chunk = trunc_index >> ppc_bits;
989 LASSERT(sanity_check(ext) == 0);
990 LASSERT(ext->oe_state == OES_TRUNC);
991 LASSERT(!ext->oe_urgent);
993 /* Request new lu_env.
994 * We can't use that env from osc_cache_truncate_start() because
995 * it's from lov_io_sub and not fully initialized. */
996 env = cl_env_get(&refcheck);
998 RETURN(PTR_ERR(env));
1000 io = &osc_env_info(env)->oti_io;
1001 io->ci_obj = cl_object_top(osc2cl(obj));
1002 io->ci_ignore_layout = 1;
1003 rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
1007 /* discard all pages with index greater than trunc_index */
1008 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
1010 pgoff_t index = osc_index(oap2osc(oap));
1011 struct cl_page *page = oap2cl_page(oap);
1013 LASSERT(list_empty(&oap->oap_rpc_item));
1015 /* only discard the pages with their index greater than
1016 * trunc_index, and ... */
1017 if (index < trunc_index ||
1018 (index == trunc_index && partial)) {
1019 /* accounting how many pages remaining in the chunk
1020 * so that we can calculate grants correctly. */
1021 if (index >> ppc_bits == trunc_chunk)
1026 list_del_init(&oap->oap_pending_item);
1029 lu_ref_add(&page->cp_reference, "truncate", current);
1031 if (cl_page_own(env, io, page) == 0) {
1032 cl_page_discard(env, io, page);
1033 cl_page_disown(env, io, page);
1035 LASSERT(page->cp_state == CPS_FREEING);
1039 lu_ref_del(&page->cp_reference, "truncate", current);
1040 cl_page_put(env, page);
1045 EASSERTF(ergo(ext->oe_start >= trunc_index + !!partial,
1046 ext->oe_nr_pages == 0),
1047 ext, "trunc_index %lu, partial %d\n", trunc_index, partial);
1049 osc_object_lock(obj);
1050 if (ext->oe_nr_pages == 0) {
1051 LASSERT(pages_in_chunk == 0);
1052 grants = ext->oe_grants;
1054 } else { /* calculate how many grants we can free */
1055 int chunks = (ext->oe_end >> ppc_bits) - trunc_chunk;
1059 /* if there is no pages in this chunk, we can also free grants
1060 * for the last chunk */
1061 if (pages_in_chunk == 0) {
1062 /* if this is the 1st chunk and no pages in this chunk,
1063 * ext->oe_nr_pages must be zero, so we should be in
1064 * the other if-clause. */
1065 LASSERT(trunc_chunk > 0);
1070 /* this is what we can free from this extent */
1071 grants = chunks << cli->cl_chunkbits;
1072 ext->oe_grants -= grants;
1073 last_index = ((trunc_chunk + 1) << ppc_bits) - 1;
1074 ext->oe_end = min(last_index, ext->oe_max_end);
1075 LASSERT(ext->oe_end >= ext->oe_start);
1076 LASSERT(ext->oe_grants > 0);
1078 osc_object_unlock(obj);
1080 if (grants > 0 || nr_pages > 0)
1081 osc_free_grant(cli, nr_pages, grants, grants);
1084 cl_io_fini(env, io);
1085 cl_env_put(env, &refcheck);
1090 * This function is used to make the extent prepared for transfer.
1091 * A race with flusing page - ll_writepage() has to be handled cautiously.
1093 static int osc_extent_make_ready(const struct lu_env *env,
1094 struct osc_extent *ext)
1096 struct osc_async_page *oap;
1097 struct osc_async_page *last = NULL;
1098 struct osc_object *obj = ext->oe_obj;
1099 unsigned int page_count = 0;
1103 /* we're going to grab page lock, so object lock must not be taken. */
1104 LASSERT(sanity_check(ext) == 0);
1105 /* in locking state, any process should not touch this extent. */
1106 EASSERT(ext->oe_state == OES_LOCKING, ext);
1107 EASSERT(ext->oe_owner != NULL, ext);
1109 OSC_EXTENT_DUMP(D_CACHE, ext, "make ready\n");
1111 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1113 if (last == NULL || last->oap_obj_off < oap->oap_obj_off)
1116 /* checking ASYNC_READY is race safe */
1117 if ((oap->oap_async_flags & ASYNC_READY) != 0)
1120 rc = osc_make_ready(env, oap, OBD_BRW_WRITE);
1123 spin_lock(&oap->oap_lock);
1124 oap->oap_async_flags |= ASYNC_READY;
1125 spin_unlock(&oap->oap_lock);
1128 LASSERT((oap->oap_async_flags & ASYNC_READY) != 0);
1131 LASSERTF(0, "unknown return code: %d\n", rc);
1135 LASSERT(page_count == ext->oe_nr_pages);
1136 LASSERT(last != NULL);
1137 /* the last page is the only one we need to refresh its count by
1138 * the size of file. */
1139 if (!(last->oap_async_flags & ASYNC_COUNT_STABLE)) {
1140 int last_oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE);
1141 LASSERT(last_oap_count > 0);
1142 LASSERT(last->oap_page_off + last_oap_count <= PAGE_SIZE);
1143 last->oap_count = last_oap_count;
1144 spin_lock(&last->oap_lock);
1145 last->oap_async_flags |= ASYNC_COUNT_STABLE;
1146 spin_unlock(&last->oap_lock);
1149 /* for the rest of pages, we don't need to call osf_refresh_count()
1150 * because it's known they are not the last page */
1151 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1152 if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
1153 oap->oap_count = PAGE_SIZE - oap->oap_page_off;
1154 spin_lock(&oap->oap_lock);
1155 oap->oap_async_flags |= ASYNC_COUNT_STABLE;
1156 spin_unlock(&oap->oap_lock);
1160 osc_object_lock(obj);
1161 osc_extent_state_set(ext, OES_RPC);
1162 osc_object_unlock(obj);
1163 /* get a refcount for RPC. */
1164 osc_extent_get(ext);
1170 * Quick and simple version of osc_extent_find(). This function is frequently
1171 * called to expand the extent for the same IO. To expand the extent, the
1172 * page index must be in the same or next chunk of ext->oe_end.
1174 static int osc_extent_expand(struct osc_extent *ext, pgoff_t index,
1175 unsigned int *grants)
1177 struct osc_object *obj = ext->oe_obj;
1178 struct client_obd *cli = osc_cli(obj);
1179 struct osc_extent *next;
1180 int ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
1181 pgoff_t chunk = index >> ppc_bits;
1184 unsigned int chunksize = 1 << cli->cl_chunkbits;
1188 LASSERT(ext->oe_max_end >= index && ext->oe_start <= index);
1189 osc_object_lock(obj);
1190 LASSERT(sanity_check_nolock(ext) == 0);
1191 end_chunk = ext->oe_end >> ppc_bits;
1192 if (chunk > end_chunk + 1)
1193 GOTO(out, rc = -ERANGE);
1195 if (end_chunk >= chunk)
1198 LASSERT(end_chunk + 1 == chunk);
1200 /* try to expand this extent to cover @index */
1201 end_index = min(ext->oe_max_end, ((chunk + 1) << ppc_bits) - 1);
1203 /* don't go over the maximum extent size reported by server */
1204 if (end_index - ext->oe_start + 1 > cli->cl_max_extent_pages)
1205 GOTO(out, rc = -ERANGE);
1207 next = next_extent(ext);
1208 if (next != NULL && next->oe_start <= end_index)
1209 /* complex mode - overlapped with the next extent,
1210 * this case will be handled by osc_extent_find() */
1211 GOTO(out, rc = -EAGAIN);
1213 ext->oe_end = end_index;
1214 ext->oe_grants += chunksize;
1215 LASSERT(*grants >= chunksize);
1216 *grants -= chunksize;
1217 EASSERTF(osc_extent_is_overlapped(obj, ext) == 0, ext,
1218 "overlapped after expanding for %lu.\n", index);
1222 osc_object_unlock(obj);
1226 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
1227 const char *func, int line)
1229 struct osc_extent *ext;
1232 if (!cfs_cdebug_show(level, DEBUG_SUBSYSTEM))
1235 CDEBUG(level, "Dump object %p extents at %s:%d, mppr: %u.\n",
1236 obj, func, line, osc_cli(obj)->cl_max_pages_per_rpc);
1238 /* osc_object_lock(obj); */
1240 for (ext = first_extent(obj); ext != NULL; ext = next_extent(ext))
1241 OSC_EXTENT_DUMP(level, ext, "in tree %d.\n", cnt++);
1244 list_for_each_entry(ext, &obj->oo_hp_exts, oe_link)
1245 OSC_EXTENT_DUMP(level, ext, "hp %d.\n", cnt++);
1248 list_for_each_entry(ext, &obj->oo_urgent_exts, oe_link)
1249 OSC_EXTENT_DUMP(level, ext, "urgent %d.\n", cnt++);
1252 list_for_each_entry(ext, &obj->oo_reading_exts, oe_link)
1253 OSC_EXTENT_DUMP(level, ext, "reading %d.\n", cnt++);
1254 /* osc_object_unlock(obj); */
1257 /* ------------------ osc extent end ------------------ */
1259 static inline int osc_is_ready(struct osc_object *osc)
1261 return !list_empty(&osc->oo_ready_item) ||
1262 !list_empty(&osc->oo_hp_ready_item);
1265 #define OSC_IO_DEBUG(OSC, STR, args...) \
1266 CDEBUG(D_CACHE, "obj %p ready %d|%c|%c wr %d|%c|%c rd %d|%c " STR, \
1267 (OSC), osc_is_ready(OSC), \
1268 list_empty_marker(&(OSC)->oo_hp_ready_item), \
1269 list_empty_marker(&(OSC)->oo_ready_item), \
1270 atomic_read(&(OSC)->oo_nr_writes), \
1271 list_empty_marker(&(OSC)->oo_hp_exts), \
1272 list_empty_marker(&(OSC)->oo_urgent_exts), \
1273 atomic_read(&(OSC)->oo_nr_reads), \
1274 list_empty_marker(&(OSC)->oo_reading_exts), \
1277 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
1280 struct osc_page *opg = oap2osc_page(oap);
1281 struct cl_page *page = oap2cl_page(oap);
1284 LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
1287 result = cl_page_make_ready(env, page, CRT_WRITE);
1289 opg->ops_submit_time = cfs_time_current();
1293 static int osc_refresh_count(const struct lu_env *env,
1294 struct osc_async_page *oap, int cmd)
1296 struct osc_page *opg = oap2osc_page(oap);
1297 pgoff_t index = osc_index(oap2osc(oap));
1298 struct cl_object *obj;
1299 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
1303 /* readpage queues with _COUNT_STABLE, shouldn't get here. */
1304 LASSERT(!(cmd & OBD_BRW_READ));
1305 LASSERT(opg != NULL);
1306 obj = opg->ops_cl.cpl_obj;
1308 cl_object_attr_lock(obj);
1309 result = cl_object_attr_get(env, obj, attr);
1310 cl_object_attr_unlock(obj);
1313 kms = attr->cat_kms;
1314 if (cl_offset(obj, index) >= kms)
1315 /* catch race with truncate */
1317 else if (cl_offset(obj, index + 1) > kms)
1318 /* catch sub-page write at end of file */
1319 return kms % PAGE_SIZE;
1324 static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
1327 struct osc_page *opg = oap2osc_page(oap);
1328 struct cl_page *page = oap2cl_page(oap);
1329 enum cl_req_type crt;
1334 cmd &= ~OBD_BRW_NOQUOTA;
1335 LASSERTF(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ),
1336 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1337 LASSERTF(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE),
1338 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1339 LASSERT(opg->ops_transfer_pinned);
1341 crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
1342 /* Clear opg->ops_transfer_pinned before VM lock is released. */
1343 opg->ops_transfer_pinned = 0;
1345 opg->ops_submit_time = 0;
1346 srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
1349 if (rc == 0 && srvlock) {
1350 struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
1351 struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
1352 size_t bytes = oap->oap_count;
1354 if (crt == CRT_READ)
1355 stats->os_lockless_reads += bytes;
1357 stats->os_lockless_writes += bytes;
1361 * This has to be the last operation with the page, as locks are
1362 * released in cl_page_completion() and nothing except for the
1363 * reference counter protects page from concurrent reclaim.
1365 lu_ref_del(&page->cp_reference, "transfer", page);
1367 cl_page_completion(env, page, crt, rc);
1368 cl_page_put(env, page);
1373 #define OSC_DUMP_GRANT(lvl, cli, fmt, args...) do { \
1374 struct client_obd *__tmp = (cli); \
1375 CDEBUG(lvl, "%s: grant { dirty: %ld/%ld dirty_pages: %ld/%lu " \
1376 "dropped: %ld avail: %ld, dirty_grant: %ld, " \
1377 "reserved: %ld, flight: %d } lru {in list: %ld, " \
1378 "left: %ld, waiters: %d }" fmt "\n", \
1380 __tmp->cl_dirty_pages, __tmp->cl_dirty_max_pages, \
1381 atomic_long_read(&obd_dirty_pages), obd_max_dirty_pages, \
1382 __tmp->cl_lost_grant, __tmp->cl_avail_grant, \
1383 __tmp->cl_dirty_grant, \
1384 __tmp->cl_reserved_grant, __tmp->cl_w_in_flight, \
1385 atomic_long_read(&__tmp->cl_lru_in_list), \
1386 atomic_long_read(&__tmp->cl_lru_busy), \
1387 atomic_read(&__tmp->cl_lru_shrinkers), ##args); \
1390 /* caller must hold loi_list_lock */
1391 static void osc_consume_write_grant(struct client_obd *cli,
1392 struct brw_page *pga)
1394 assert_spin_locked(&cli->cl_loi_list_lock);
1395 LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
1396 atomic_long_inc(&obd_dirty_pages);
1397 cli->cl_dirty_pages++;
1398 pga->flag |= OBD_BRW_FROM_GRANT;
1399 CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
1400 PAGE_SIZE, pga, pga->pg);
1401 osc_update_next_shrink(cli);
1404 /* the companion to osc_consume_write_grant, called when a brw has completed.
1405 * must be called with the loi lock held. */
1406 static void osc_release_write_grant(struct client_obd *cli,
1407 struct brw_page *pga)
1411 assert_spin_locked(&cli->cl_loi_list_lock);
1412 if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
1417 pga->flag &= ~OBD_BRW_FROM_GRANT;
1418 atomic_long_dec(&obd_dirty_pages);
1419 cli->cl_dirty_pages--;
1420 if (pga->flag & OBD_BRW_NOCACHE) {
1421 pga->flag &= ~OBD_BRW_NOCACHE;
1422 atomic_long_dec(&obd_dirty_transit_pages);
1423 cli->cl_dirty_transit--;
1429 * To avoid sleeping with object lock held, it's good for us allocate enough
1430 * grants before entering into critical section.
1432 * client_obd_list_lock held by caller
1434 static int osc_reserve_grant(struct client_obd *cli, unsigned int bytes)
1438 if (cli->cl_avail_grant >= bytes) {
1439 cli->cl_avail_grant -= bytes;
1440 cli->cl_reserved_grant += bytes;
1446 static void __osc_unreserve_grant(struct client_obd *cli,
1447 unsigned int reserved, unsigned int unused)
1449 /* it's quite normal for us to get more grant than reserved.
1450 * Thinking about a case that two extents merged by adding a new
1451 * chunk, we can save one extent tax. If extent tax is greater than
1452 * one chunk, we can save more grant by adding a new chunk */
1453 cli->cl_reserved_grant -= reserved;
1454 if (unused > reserved) {
1455 cli->cl_avail_grant += reserved;
1456 cli->cl_lost_grant += unused - reserved;
1457 cli->cl_dirty_grant -= unused - reserved;
1459 cli->cl_avail_grant += unused;
1460 cli->cl_dirty_grant += reserved - unused;
1464 static void osc_unreserve_grant(struct client_obd *cli,
1465 unsigned int reserved, unsigned int unused)
1467 spin_lock(&cli->cl_loi_list_lock);
1468 __osc_unreserve_grant(cli, reserved, unused);
1470 osc_wake_cache_waiters(cli);
1471 spin_unlock(&cli->cl_loi_list_lock);
1475 * Free grant after IO is finished or canceled.
1477 * @lost_grant is used to remember how many grants we have allocated but not
1478 * used, we should return these grants to OST. There're two cases where grants
1481 * 2. blocksize at OST is less than PAGE_SIZE and a partial page was
1482 * written. In this case OST may use less chunks to serve this partial
1483 * write. OSTs don't actually know the page size on the client side. so
1484 * clients have to calculate lost grant by the blocksize on the OST.
1485 * See filter_grant_check() for details.
1487 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
1488 unsigned int lost_grant, unsigned int dirty_grant)
1490 unsigned long grant;
1492 grant = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
1494 spin_lock(&cli->cl_loi_list_lock);
1495 atomic_long_sub(nr_pages, &obd_dirty_pages);
1496 cli->cl_dirty_pages -= nr_pages;
1497 cli->cl_lost_grant += lost_grant;
1498 cli->cl_dirty_grant -= dirty_grant;
1499 if (cli->cl_avail_grant < grant && cli->cl_lost_grant >= grant) {
1500 /* borrow some grant from truncate to avoid the case that
1501 * truncate uses up all avail grant */
1502 cli->cl_lost_grant -= grant;
1503 cli->cl_avail_grant += grant;
1505 osc_wake_cache_waiters(cli);
1506 spin_unlock(&cli->cl_loi_list_lock);
1507 CDEBUG(D_CACHE, "lost %u grant: %lu avail: %lu dirty: %lu/%lu\n",
1508 lost_grant, cli->cl_lost_grant,
1509 cli->cl_avail_grant, cli->cl_dirty_pages << PAGE_SHIFT,
1510 cli->cl_dirty_grant);
1514 * The companion to osc_enter_cache(), called when @oap is no longer part of
1515 * the dirty accounting due to error.
1517 static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap)
1519 spin_lock(&cli->cl_loi_list_lock);
1520 osc_release_write_grant(cli, &oap->oap_brw_page);
1521 spin_unlock(&cli->cl_loi_list_lock);
1525 * Non-blocking version of osc_enter_cache() that consumes grant only when it
1528 static int osc_enter_cache_try(struct client_obd *cli,
1529 struct osc_async_page *oap,
1530 int bytes, int transient)
1534 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1536 rc = osc_reserve_grant(cli, bytes);
1540 if (cli->cl_dirty_pages < cli->cl_dirty_max_pages &&
1541 1 + atomic_long_read(&obd_dirty_pages) <= obd_max_dirty_pages) {
1542 osc_consume_write_grant(cli, &oap->oap_brw_page);
1544 cli->cl_dirty_transit++;
1545 atomic_long_inc(&obd_dirty_transit_pages);
1546 oap->oap_brw_flags |= OBD_BRW_NOCACHE;
1550 __osc_unreserve_grant(cli, bytes, bytes);
1556 static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
1559 spin_lock(&cli->cl_loi_list_lock);
1560 rc = list_empty(&ocw->ocw_entry);
1561 spin_unlock(&cli->cl_loi_list_lock);
1566 * The main entry to reserve dirty page accounting. Usually the grant reserved
1567 * in this function will be freed in bulk in osc_free_grant() unless it fails
1568 * to add osc cache, in that case, it will be freed in osc_exit_cache().
1570 * The process will be put into sleep if it's already run out of grant.
1572 static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
1573 struct osc_async_page *oap, int bytes)
1575 struct osc_object *osc = oap->oap_obj;
1576 struct lov_oinfo *loi = osc->oo_oinfo;
1577 struct osc_cache_waiter ocw;
1578 struct l_wait_info lwi;
1582 lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(AT_OFF ? obd_timeout : at_max),
1583 NULL, LWI_ON_SIGNAL_NOOP, NULL);
1585 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1587 spin_lock(&cli->cl_loi_list_lock);
1589 /* force the caller to try sync io. this can jump the list
1590 * of queued writes and create a discontiguous rpc stream */
1591 if (OBD_FAIL_CHECK(OBD_FAIL_OSC_NO_GRANT) ||
1592 cli->cl_dirty_max_pages == 0 ||
1593 cli->cl_ar.ar_force_sync || loi->loi_ar.ar_force_sync) {
1594 OSC_DUMP_GRANT(D_CACHE, cli, "forced sync i/o\n");
1595 GOTO(out, rc = -EDQUOT);
1598 /* Hopefully normal case - cache space and write credits available */
1599 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1600 OSC_DUMP_GRANT(D_CACHE, cli, "granted from cache\n");
1604 /* We can get here for two reasons: too many dirty pages in cache, or
1605 * run out of grants. In both cases we should write dirty pages out.
1606 * Adding a cache waiter will trigger urgent write-out no matter what
1608 * The exiting condition is no avail grants and no dirty pages caching,
1609 * that really means there is no space on the OST. */
1610 init_waitqueue_head(&ocw.ocw_waitq);
1612 ocw.ocw_grant = bytes;
1613 while (cli->cl_dirty_pages > 0 || cli->cl_w_in_flight > 0) {
1614 list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
1616 spin_unlock(&cli->cl_loi_list_lock);
1618 osc_io_unplug_async(env, cli, NULL);
1620 CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
1621 cli_name(cli), &ocw, oap);
1623 rc = l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
1625 spin_lock(&cli->cl_loi_list_lock);
1628 /* l_wait_event is interrupted by signal or timed out */
1629 list_del_init(&ocw.ocw_entry);
1632 LASSERT(list_empty(&ocw.ocw_entry));
1637 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1645 OSC_DUMP_GRANT(D_CACHE, cli, "finally got grant space\n");
1648 OSC_DUMP_GRANT(D_CACHE, cli,
1649 "timeout, fall back to sync i/o\n");
1650 osc_extent_tree_dump(D_CACHE, osc);
1651 /* fall back to synchronous I/O */
1655 /* Ensures restartability - LU-3581 */
1656 OSC_DUMP_GRANT(D_CACHE, cli, "interrupted\n");
1660 OSC_DUMP_GRANT(D_CACHE, cli,
1661 "no grant space, fall back to sync i/o\n");
1664 CDEBUG(D_CACHE, "%s: event for cache space @ %p never arrived "
1665 "due to %d, fall back to sync i/o\n",
1666 cli_name(cli), &ocw, rc);
1671 spin_unlock(&cli->cl_loi_list_lock);
1675 /* caller must hold loi_list_lock */
1676 void osc_wake_cache_waiters(struct client_obd *cli)
1678 struct list_head *l, *tmp;
1679 struct osc_cache_waiter *ocw;
1682 list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
1683 ocw = list_entry(l, struct osc_cache_waiter, ocw_entry);
1684 list_del_init(&ocw->ocw_entry);
1686 ocw->ocw_rc = -EDQUOT;
1687 /* we can't dirty more */
1688 if ((cli->cl_dirty_pages >= cli->cl_dirty_max_pages) ||
1689 (1 + atomic_long_read(&obd_dirty_pages) >
1690 obd_max_dirty_pages)) {
1691 CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
1692 "osc max %ld, sys max %ld\n",
1693 cli->cl_dirty_pages, cli->cl_dirty_max_pages,
1694 obd_max_dirty_pages);
1698 if (osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
1701 CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
1702 ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
1704 wake_up(&ocw->ocw_waitq);
1709 EXPORT_SYMBOL(osc_wake_cache_waiters);
1711 static int osc_max_rpc_in_flight(struct client_obd *cli, struct osc_object *osc)
1713 int hprpc = !!list_empty(&osc->oo_hp_exts);
1714 return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
1717 /* This maintains the lists of pending pages to read/write for a given object
1718 * (lop). This is used by osc_check_rpcs->osc_next_obj() and osc_list_maint()
1719 * to quickly find objects that are ready to send an RPC. */
1720 static int osc_makes_rpc(struct client_obd *cli, struct osc_object *osc,
1723 int invalid_import = 0;
1726 /* if we have an invalid import we want to drain the queued pages
1727 * by forcing them through rpcs that immediately fail and complete
1728 * the pages. recovery relies on this to empty the queued pages
1729 * before canceling the locks and evicting down the llite pages */
1730 if ((cli->cl_import == NULL || cli->cl_import->imp_invalid))
1733 if (cmd & OBD_BRW_WRITE) {
1734 if (atomic_read(&osc->oo_nr_writes) == 0)
1736 if (invalid_import) {
1737 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1740 if (!list_empty(&osc->oo_hp_exts)) {
1741 CDEBUG(D_CACHE, "high prio request forcing RPC\n");
1744 if (!list_empty(&osc->oo_urgent_exts)) {
1745 CDEBUG(D_CACHE, "urgent request forcing RPC\n");
1748 /* trigger a write rpc stream as long as there are dirtiers
1749 * waiting for space. as they're waiting, they're not going to
1750 * create more pages to coalesce with what's waiting.. */
1751 if (!list_empty(&cli->cl_cache_waiters)) {
1752 CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
1755 if (!list_empty(&osc->oo_full_exts)) {
1756 CDEBUG(D_CACHE, "full extent ready, make an RPC\n");
1760 if (atomic_read(&osc->oo_nr_reads) == 0)
1762 if (invalid_import) {
1763 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1766 /* all read are urgent. */
1767 if (!list_empty(&osc->oo_reading_exts))
1774 static void osc_update_pending(struct osc_object *obj, int cmd, int delta)
1776 struct client_obd *cli = osc_cli(obj);
1777 if (cmd & OBD_BRW_WRITE) {
1778 atomic_add(delta, &obj->oo_nr_writes);
1779 atomic_add(delta, &cli->cl_pending_w_pages);
1780 LASSERT(atomic_read(&obj->oo_nr_writes) >= 0);
1782 atomic_add(delta, &obj->oo_nr_reads);
1783 atomic_add(delta, &cli->cl_pending_r_pages);
1784 LASSERT(atomic_read(&obj->oo_nr_reads) >= 0);
1786 OSC_IO_DEBUG(obj, "update pending cmd %d delta %d.\n", cmd, delta);
1789 static int osc_makes_hprpc(struct osc_object *obj)
1791 return !list_empty(&obj->oo_hp_exts);
1794 static void on_list(struct list_head *item, struct list_head *list,
1797 if (list_empty(item) && should_be_on)
1798 list_add_tail(item, list);
1799 else if (!list_empty(item) && !should_be_on)
1800 list_del_init(item);
1803 /* maintain the osc's cli list membership invariants so that osc_send_oap_rpc
1804 * can find pages to build into rpcs quickly */
1805 static int __osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1807 if (osc_makes_hprpc(osc)) {
1809 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list, 0);
1810 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
1812 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
1813 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list,
1814 osc_makes_rpc(cli, osc, OBD_BRW_WRITE) ||
1815 osc_makes_rpc(cli, osc, OBD_BRW_READ));
1818 on_list(&osc->oo_write_item, &cli->cl_loi_write_list,
1819 atomic_read(&osc->oo_nr_writes) > 0);
1821 on_list(&osc->oo_read_item, &cli->cl_loi_read_list,
1822 atomic_read(&osc->oo_nr_reads) > 0);
1824 return osc_is_ready(osc);
1827 static int osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1831 spin_lock(&cli->cl_loi_list_lock);
1832 is_ready = __osc_list_maint(cli, osc);
1833 spin_unlock(&cli->cl_loi_list_lock);
1838 /* this is trying to propogate async writeback errors back up to the
1839 * application. As an async write fails we record the error code for later if
1840 * the app does an fsync. As long as errors persist we force future rpcs to be
1841 * sync so that the app can get a sync error and break the cycle of queueing
1842 * pages for which writeback will fail. */
1843 static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
1850 ar->ar_force_sync = 1;
1851 ar->ar_min_xid = ptlrpc_sample_next_xid();
1856 if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
1857 ar->ar_force_sync = 0;
1860 /* this must be called holding the loi list lock to give coverage to exit_cache,
1861 * async_flag maintenance, and oap_request */
1862 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
1863 struct osc_async_page *oap, int sent, int rc)
1865 struct osc_object *osc = oap->oap_obj;
1866 struct lov_oinfo *loi = osc->oo_oinfo;
1870 if (oap->oap_request != NULL) {
1871 xid = ptlrpc_req_xid(oap->oap_request);
1872 ptlrpc_req_finished(oap->oap_request);
1873 oap->oap_request = NULL;
1876 /* As the transfer for this page is being done, clear the flags */
1877 spin_lock(&oap->oap_lock);
1878 oap->oap_async_flags = 0;
1879 spin_unlock(&oap->oap_lock);
1880 oap->oap_interrupted = 0;
1882 if (oap->oap_cmd & OBD_BRW_WRITE && xid > 0) {
1883 spin_lock(&cli->cl_loi_list_lock);
1884 osc_process_ar(&cli->cl_ar, xid, rc);
1885 osc_process_ar(&loi->loi_ar, xid, rc);
1886 spin_unlock(&cli->cl_loi_list_lock);
1889 rc = osc_completion(env, oap, oap->oap_cmd, rc);
1891 CERROR("completion on oap %p obj %p returns %d.\n",
1897 struct extent_rpc_data {
1898 struct list_head *erd_rpc_list;
1899 unsigned int erd_page_count;
1900 unsigned int erd_max_pages;
1901 unsigned int erd_max_chunks;
1902 unsigned int erd_max_extents;
1905 static inline unsigned osc_extent_chunks(const struct osc_extent *ext)
1907 struct client_obd *cli = osc_cli(ext->oe_obj);
1908 unsigned ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
1910 return (ext->oe_end >> ppc_bits) - (ext->oe_start >> ppc_bits) + 1;
1914 * Try to add extent to one RPC. We need to think about the following things:
1915 * - # of pages must not be over max_pages_per_rpc
1916 * - extent must be compatible with previous ones
1918 static int try_to_add_extent_for_io(struct client_obd *cli,
1919 struct osc_extent *ext,
1920 struct extent_rpc_data *data)
1922 struct osc_extent *tmp;
1923 unsigned int chunk_count;
1924 struct osc_async_page *oap = list_first_entry(&ext->oe_pages,
1925 struct osc_async_page,
1929 EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE),
1931 OSC_EXTENT_DUMP(D_CACHE, ext, "trying to add this extent\n");
1933 if (data->erd_max_extents == 0)
1936 chunk_count = osc_extent_chunks(ext);
1937 EASSERTF(data->erd_page_count != 0 ||
1938 chunk_count <= data->erd_max_chunks, ext,
1939 "The first extent to be fit in a RPC contains %u chunks, "
1940 "which is over the limit %u.\n", chunk_count,
1941 data->erd_max_chunks);
1942 if (chunk_count > data->erd_max_chunks)
1945 data->erd_max_pages = max(ext->oe_mppr, data->erd_max_pages);
1946 EASSERTF(data->erd_page_count != 0 ||
1947 ext->oe_nr_pages <= data->erd_max_pages, ext,
1948 "The first extent to be fit in a RPC contains %u pages, "
1949 "which is over the limit %u.\n", ext->oe_nr_pages,
1950 data->erd_max_pages);
1951 if (data->erd_page_count + ext->oe_nr_pages > data->erd_max_pages)
1954 list_for_each_entry(tmp, data->erd_rpc_list, oe_link) {
1955 struct osc_async_page *oap2;
1956 oap2 = list_first_entry(&tmp->oe_pages, struct osc_async_page,
1958 EASSERT(tmp->oe_owner == current, tmp);
1960 if (overlapped(tmp, ext)) {
1961 OSC_EXTENT_DUMP(D_ERROR, tmp, "overlapped %p.\n", ext);
1965 if (oap2cl_page(oap)->cp_type != oap2cl_page(oap2)->cp_type) {
1966 CDEBUG(D_CACHE, "Do not permit different types of IO "
1971 if (tmp->oe_srvlock != ext->oe_srvlock ||
1972 !tmp->oe_grants != !ext->oe_grants ||
1973 tmp->oe_no_merge || ext->oe_no_merge)
1976 /* remove break for strict check */
1980 data->erd_max_extents--;
1981 data->erd_max_chunks -= chunk_count;
1982 data->erd_page_count += ext->oe_nr_pages;
1983 list_move_tail(&ext->oe_link, data->erd_rpc_list);
1984 ext->oe_owner = current;
1988 static inline unsigned osc_max_write_chunks(const struct client_obd *cli)
1993 * The maximum size of a single transaction is about 64MB in ZFS.
1994 * #define DMU_MAX_ACCESS (64 * 1024 * 1024)
1996 * Since ZFS is a copy-on-write file system, a single dirty page in
1997 * a chunk will result in the rewrite of the whole chunk, therefore
1998 * an RPC shouldn't be allowed to contain too many chunks otherwise
1999 * it will make transaction size much bigger than 64MB, especially
2000 * with big block size for ZFS.
2002 * This piece of code is to make sure that OSC won't send write RPCs
2003 * with too many chunks. The maximum chunk size that an RPC can cover
2004 * is set to PTLRPC_MAX_BRW_SIZE, which is defined to 16MB. Ideally
2005 * OST should tell the client what the biggest transaction size is,
2006 * but it's good enough for now.
2008 * This limitation doesn't apply to ldiskfs, which allows as many
2009 * chunks in one RPC as we want. However, it won't have any benefits
2010 * to have too many discontiguous pages in one RPC.
2012 * An osc_extent won't cover over a RPC size, so the chunks in an
2013 * osc_extent won't bigger than PTLRPC_MAX_BRW_SIZE >> chunkbits.
2015 return PTLRPC_MAX_BRW_SIZE >> cli->cl_chunkbits;
2019 * In order to prevent multiple ptlrpcd from breaking contiguous extents,
2020 * get_write_extent() takes all appropriate extents in atomic.
2022 * The following policy is used to collect extents for IO:
2023 * 1. Add as many HP extents as possible;
2024 * 2. Add the first urgent extent in urgent extent list and take it out of
2026 * 3. Add subsequent extents of this urgent extent;
2027 * 4. If urgent list is not empty, goto 2;
2028 * 5. Traverse the extent tree from the 1st extent;
2029 * 6. Above steps exit if there is no space in this RPC.
2031 static unsigned int get_write_extents(struct osc_object *obj,
2032 struct list_head *rpclist)
2034 struct client_obd *cli = osc_cli(obj);
2035 struct osc_extent *ext;
2036 struct extent_rpc_data data = {
2037 .erd_rpc_list = rpclist,
2038 .erd_page_count = 0,
2039 .erd_max_pages = cli->cl_max_pages_per_rpc,
2040 .erd_max_chunks = osc_max_write_chunks(cli),
2041 .erd_max_extents = 256,
2044 LASSERT(osc_object_is_locked(obj));
2045 while (!list_empty(&obj->oo_hp_exts)) {
2046 ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
2048 LASSERT(ext->oe_state == OES_CACHE);
2049 if (!try_to_add_extent_for_io(cli, ext, &data))
2050 return data.erd_page_count;
2051 EASSERT(ext->oe_nr_pages <= data.erd_max_pages, ext);
2053 if (data.erd_page_count == data.erd_max_pages)
2054 return data.erd_page_count;
2056 while (!list_empty(&obj->oo_urgent_exts)) {
2057 ext = list_entry(obj->oo_urgent_exts.next,
2058 struct osc_extent, oe_link);
2059 if (!try_to_add_extent_for_io(cli, ext, &data))
2060 return data.erd_page_count;
2062 if (data.erd_page_count == data.erd_max_pages)
2063 return data.erd_page_count;
2065 /* One key difference between full extents and other extents: full
2066 * extents can usually only be added if the rpclist was empty, so if we
2067 * can't add one, we continue on to trying to add normal extents. This
2068 * is so we don't miss adding extra extents to an RPC containing high
2069 * priority or urgent extents. */
2070 while (!list_empty(&obj->oo_full_exts)) {
2071 ext = list_entry(obj->oo_full_exts.next,
2072 struct osc_extent, oe_link);
2073 if (!try_to_add_extent_for_io(cli, ext, &data))
2076 if (data.erd_page_count == data.erd_max_pages)
2077 return data.erd_page_count;
2079 ext = first_extent(obj);
2080 while (ext != NULL) {
2081 if ((ext->oe_state != OES_CACHE) ||
2082 /* this extent may be already in current rpclist */
2083 (!list_empty(&ext->oe_link) && ext->oe_owner != NULL)) {
2084 ext = next_extent(ext);
2088 if (!try_to_add_extent_for_io(cli, ext, &data))
2089 return data.erd_page_count;
2091 ext = next_extent(ext);
2093 return data.erd_page_count;
2097 osc_send_write_rpc(const struct lu_env *env, struct client_obd *cli,
2098 struct osc_object *osc)
2101 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2102 struct osc_extent *ext;
2103 struct osc_extent *tmp;
2104 struct osc_extent *first = NULL;
2105 unsigned int page_count = 0;
2110 LASSERT(osc_object_is_locked(osc));
2112 page_count = get_write_extents(osc, &rpclist);
2113 LASSERT(equi(page_count == 0, list_empty(&rpclist)));
2115 if (list_empty(&rpclist))
2118 osc_update_pending(osc, OBD_BRW_WRITE, -page_count);
2120 list_for_each_entry(ext, &rpclist, oe_link) {
2121 LASSERT(ext->oe_state == OES_CACHE ||
2122 ext->oe_state == OES_LOCK_DONE);
2123 if (ext->oe_state == OES_CACHE)
2124 osc_extent_state_set(ext, OES_LOCKING);
2126 osc_extent_state_set(ext, OES_RPC);
2129 /* we're going to grab page lock, so release object lock because
2130 * lock order is page lock -> object lock. */
2131 osc_object_unlock(osc);
2133 list_for_each_entry_safe(ext, tmp, &rpclist, oe_link) {
2134 if (ext->oe_state == OES_LOCKING) {
2135 rc = osc_extent_make_ready(env, ext);
2136 if (unlikely(rc < 0)) {
2137 list_del_init(&ext->oe_link);
2138 osc_extent_finish(env, ext, 0, rc);
2142 if (first == NULL) {
2144 srvlock = ext->oe_srvlock;
2146 LASSERT(srvlock == ext->oe_srvlock);
2150 if (!list_empty(&rpclist)) {
2151 LASSERT(page_count > 0);
2152 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_WRITE);
2153 LASSERT(list_empty(&rpclist));
2156 osc_object_lock(osc);
2161 * prepare pages for ASYNC io and put pages in send queue.
2163 * \param cmd OBD_BRW_* macroses
2164 * \param lop pending pages
2166 * \return zero if no page added to send queue.
2167 * \return 1 if pages successfully added to send queue.
2168 * \return negative on errors.
2171 osc_send_read_rpc(const struct lu_env *env, struct client_obd *cli,
2172 struct osc_object *osc)
2175 struct osc_extent *ext;
2176 struct osc_extent *next;
2177 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2178 struct extent_rpc_data data = {
2179 .erd_rpc_list = &rpclist,
2180 .erd_page_count = 0,
2181 .erd_max_pages = cli->cl_max_pages_per_rpc,
2182 .erd_max_chunks = UINT_MAX,
2183 .erd_max_extents = UINT_MAX,
2188 LASSERT(osc_object_is_locked(osc));
2189 list_for_each_entry_safe(ext, next, &osc->oo_reading_exts, oe_link) {
2190 EASSERT(ext->oe_state == OES_LOCK_DONE, ext);
2191 if (!try_to_add_extent_for_io(cli, ext, &data))
2193 osc_extent_state_set(ext, OES_RPC);
2194 EASSERT(ext->oe_nr_pages <= data.erd_max_pages, ext);
2196 LASSERT(data.erd_page_count <= data.erd_max_pages);
2198 osc_update_pending(osc, OBD_BRW_READ, -data.erd_page_count);
2200 if (!list_empty(&rpclist)) {
2201 osc_object_unlock(osc);
2203 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_READ);
2204 LASSERT(list_empty(&rpclist));
2206 osc_object_lock(osc);
2211 #define list_to_obj(list, item) ({ \
2212 struct list_head *__tmp = (list)->next; \
2213 list_del_init(__tmp); \
2214 list_entry(__tmp, struct osc_object, oo_##item); \
2217 /* This is called by osc_check_rpcs() to find which objects have pages that
2218 * we could be sending. These lists are maintained by osc_makes_rpc(). */
2219 static struct osc_object *osc_next_obj(struct client_obd *cli)
2223 /* First return objects that have blocked locks so that they
2224 * will be flushed quickly and other clients can get the lock,
2225 * then objects which have pages ready to be stuffed into RPCs */
2226 if (!list_empty(&cli->cl_loi_hp_ready_list))
2227 RETURN(list_to_obj(&cli->cl_loi_hp_ready_list, hp_ready_item));
2228 if (!list_empty(&cli->cl_loi_ready_list))
2229 RETURN(list_to_obj(&cli->cl_loi_ready_list, ready_item));
2231 /* then if we have cache waiters, return all objects with queued
2232 * writes. This is especially important when many small files
2233 * have filled up the cache and not been fired into rpcs because
2234 * they don't pass the nr_pending/object threshhold */
2235 if (!list_empty(&cli->cl_cache_waiters) &&
2236 !list_empty(&cli->cl_loi_write_list))
2237 RETURN(list_to_obj(&cli->cl_loi_write_list, write_item));
2239 /* then return all queued objects when we have an invalid import
2240 * so that they get flushed */
2241 if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
2242 if (!list_empty(&cli->cl_loi_write_list))
2243 RETURN(list_to_obj(&cli->cl_loi_write_list,
2245 if (!list_empty(&cli->cl_loi_read_list))
2246 RETURN(list_to_obj(&cli->cl_loi_read_list,
2252 /* called with the loi list lock held */
2253 static void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli)
2254 __must_hold(&cli->cl_loi_list_lock)
2256 struct osc_object *osc;
2260 while ((osc = osc_next_obj(cli)) != NULL) {
2261 struct cl_object *obj = osc2cl(osc);
2262 struct lu_ref_link link;
2264 OSC_IO_DEBUG(osc, "%lu in flight\n", rpcs_in_flight(cli));
2266 if (osc_max_rpc_in_flight(cli, osc)) {
2267 __osc_list_maint(cli, osc);
2272 spin_unlock(&cli->cl_loi_list_lock);
2273 lu_object_ref_add_at(&obj->co_lu, &link, "check", current);
2275 /* attempt some read/write balancing by alternating between
2276 * reads and writes in an object. The makes_rpc checks here
2277 * would be redundant if we were getting read/write work items
2278 * instead of objects. we don't want send_oap_rpc to drain a
2279 * partial read pending queue when we're given this object to
2280 * do io on writes while there are cache waiters */
2281 osc_object_lock(osc);
2282 if (osc_makes_rpc(cli, osc, OBD_BRW_WRITE)) {
2283 rc = osc_send_write_rpc(env, cli, osc);
2285 CERROR("Write request failed with %d\n", rc);
2287 /* osc_send_write_rpc failed, mostly because of
2290 * It can't break here, because if:
2291 * - a page was submitted by osc_io_submit, so
2293 * - no request in flight
2294 * - no subsequent request
2295 * The system will be in live-lock state,
2296 * because there is no chance to call
2297 * osc_io_unplug() and osc_check_rpcs() any
2298 * more. pdflush can't help in this case,
2299 * because it might be blocked at grabbing
2300 * the page lock as we mentioned.
2302 * Anyway, continue to drain pages. */
2306 if (osc_makes_rpc(cli, osc, OBD_BRW_READ)) {
2307 rc = osc_send_read_rpc(env, cli, osc);
2309 CERROR("Read request failed with %d\n", rc);
2311 osc_object_unlock(osc);
2313 osc_list_maint(cli, osc);
2314 lu_object_ref_del_at(&obj->co_lu, &link, "check", current);
2315 cl_object_put(env, obj);
2317 spin_lock(&cli->cl_loi_list_lock);
2321 int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
2322 struct osc_object *osc, int async)
2326 if (osc != NULL && osc_list_maint(cli, osc) == 0)
2330 spin_lock(&cli->cl_loi_list_lock);
2331 osc_check_rpcs(env, cli);
2332 spin_unlock(&cli->cl_loi_list_lock);
2334 CDEBUG(D_CACHE, "Queue writeback work for client %p.\n", cli);
2335 LASSERT(cli->cl_writeback_work != NULL);
2336 rc = ptlrpcd_queue_work(cli->cl_writeback_work);
2340 EXPORT_SYMBOL(osc_io_unplug0);
2342 int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
2343 struct page *page, loff_t offset)
2345 struct obd_export *exp = osc_export(osc);
2346 struct osc_async_page *oap = &ops->ops_oap;
2350 return cfs_size_round(sizeof(*oap));
2352 oap->oap_magic = OAP_MAGIC;
2353 oap->oap_cli = &exp->exp_obd->u.cli;
2356 oap->oap_page = page;
2357 oap->oap_obj_off = offset;
2358 LASSERT(!(offset & ~PAGE_MASK));
2360 if (cfs_capable(CFS_CAP_SYS_RESOURCE))
2361 oap->oap_brw_flags = OBD_BRW_NOQUOTA;
2363 INIT_LIST_HEAD(&oap->oap_pending_item);
2364 INIT_LIST_HEAD(&oap->oap_rpc_item);
2366 spin_lock_init(&oap->oap_lock);
2367 CDEBUG(D_INFO, "oap %p page %p obj off %llu\n",
2368 oap, page, oap->oap_obj_off);
2371 EXPORT_SYMBOL(osc_prep_async_page);
2373 int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
2374 struct osc_page *ops)
2376 struct osc_io *oio = osc_env_io(env);
2377 struct osc_extent *ext = NULL;
2378 struct osc_async_page *oap = &ops->ops_oap;
2379 struct client_obd *cli = oap->oap_cli;
2380 struct osc_object *osc = oap->oap_obj;
2383 unsigned int grants = 0;
2384 u32 brw_flags = OBD_BRW_ASYNC;
2385 int cmd = OBD_BRW_WRITE;
2386 int need_release = 0;
2390 if (oap->oap_magic != OAP_MAGIC)
2393 if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
2396 if (!list_empty(&oap->oap_pending_item) ||
2397 !list_empty(&oap->oap_rpc_item))
2400 /* Set the OBD_BRW_SRVLOCK before the page is queued. */
2401 brw_flags |= ops->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
2402 if (cfs_capable(CFS_CAP_SYS_RESOURCE)) {
2403 brw_flags |= OBD_BRW_NOQUOTA;
2404 cmd |= OBD_BRW_NOQUOTA;
2407 /* check if the file's owner/group is over quota */
2408 if (!(cmd & OBD_BRW_NOQUOTA)) {
2409 struct cl_object *obj;
2410 struct cl_attr *attr;
2411 unsigned int qid[LL_MAXQUOTAS];
2413 obj = cl_object_top(&osc->oo_cl);
2414 attr = &osc_env_info(env)->oti_attr;
2416 cl_object_attr_lock(obj);
2417 rc = cl_object_attr_get(env, obj, attr);
2418 cl_object_attr_unlock(obj);
2420 qid[USRQUOTA] = attr->cat_uid;
2421 qid[GRPQUOTA] = attr->cat_gid;
2422 qid[PRJQUOTA] = attr->cat_projid;
2423 if (rc == 0 && osc_quota_chkdq(cli, qid) == NO_QUOTA)
2430 oap->oap_page_off = ops->ops_from;
2431 oap->oap_count = ops->ops_to - ops->ops_from;
2432 /* No need to hold a lock here,
2433 * since this page is not in any list yet. */
2434 oap->oap_async_flags = 0;
2435 oap->oap_brw_flags = brw_flags;
2437 OSC_IO_DEBUG(osc, "oap %p page %p added for cmd %d\n",
2438 oap, oap->oap_page, oap->oap_cmd & OBD_BRW_RWMASK);
2440 index = osc_index(oap2osc(oap));
2442 /* Add this page into extent by the following steps:
2443 * 1. if there exists an active extent for this IO, mostly this page
2444 * can be added to the active extent and sometimes we need to
2445 * expand extent to accomodate this page;
2446 * 2. otherwise, a new extent will be allocated. */
2448 ext = oio->oi_active;
2449 if (ext != NULL && ext->oe_start <= index && ext->oe_max_end >= index) {
2450 /* one chunk plus extent overhead must be enough to write this
2452 grants = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
2453 if (ext->oe_end >= index)
2456 /* it doesn't need any grant to dirty this page */
2457 spin_lock(&cli->cl_loi_list_lock);
2458 rc = osc_enter_cache_try(cli, oap, grants, 0);
2459 spin_unlock(&cli->cl_loi_list_lock);
2460 if (rc == 0) { /* try failed */
2463 } else if (ext->oe_end < index) {
2465 /* try to expand this extent */
2466 rc = osc_extent_expand(ext, index, &tmp);
2469 /* don't free reserved grant */
2471 OSC_EXTENT_DUMP(D_CACHE, ext,
2472 "expanded for %lu.\n", index);
2473 osc_unreserve_grant(cli, grants, tmp);
2478 } else if (ext != NULL) {
2479 /* index is located outside of active extent */
2483 osc_extent_release(env, ext);
2484 oio->oi_active = NULL;
2489 tmp = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
2491 /* try to find new extent to cover this page */
2492 LASSERT(oio->oi_active == NULL);
2493 /* we may have allocated grant for this page if we failed
2494 * to expand the previous active extent. */
2495 LASSERT(ergo(grants > 0, grants >= tmp));
2499 /* we haven't allocated grant for this page. */
2500 rc = osc_enter_cache(env, cli, oap, tmp);
2507 ext = osc_extent_find(env, osc, index, &tmp);
2509 LASSERT(tmp == grants);
2510 osc_exit_cache(cli, oap);
2514 oio->oi_active = ext;
2518 osc_unreserve_grant(cli, grants, tmp);
2521 LASSERT(ergo(rc == 0, ext != NULL));
2523 EASSERTF(ext->oe_end >= index && ext->oe_start <= index,
2524 ext, "index = %lu.\n", index);
2525 LASSERT((oap->oap_brw_flags & OBD_BRW_FROM_GRANT) != 0);
2527 osc_object_lock(osc);
2528 if (ext->oe_nr_pages == 0)
2529 ext->oe_srvlock = ops->ops_srvlock;
2531 LASSERT(ext->oe_srvlock == ops->ops_srvlock);
2533 list_add_tail(&oap->oap_pending_item, &ext->oe_pages);
2534 osc_object_unlock(osc);
2540 int osc_teardown_async_page(const struct lu_env *env,
2541 struct osc_object *obj, struct osc_page *ops)
2543 struct osc_async_page *oap = &ops->ops_oap;
2547 LASSERT(oap->oap_magic == OAP_MAGIC);
2549 CDEBUG(D_INFO, "teardown oap %p page %p at index %lu.\n",
2550 oap, ops, osc_index(oap2osc(oap)));
2552 if (!list_empty(&oap->oap_rpc_item)) {
2553 CDEBUG(D_CACHE, "oap %p is not in cache.\n", oap);
2555 } else if (!list_empty(&oap->oap_pending_item)) {
2556 struct osc_extent *ext = NULL;
2558 osc_object_lock(obj);
2559 ext = osc_extent_lookup(obj, osc_index(oap2osc(oap)));
2560 osc_object_unlock(obj);
2561 /* only truncated pages are allowed to be taken out.
2562 * See osc_extent_truncate() and osc_cache_truncate_start()
2564 if (ext != NULL && ext->oe_state != OES_TRUNC) {
2565 OSC_EXTENT_DUMP(D_ERROR, ext, "trunc at %lu.\n",
2566 osc_index(oap2osc(oap)));
2570 osc_extent_put(env, ext);
2576 * This is called when a page is picked up by kernel to write out.
2578 * We should find out the corresponding extent and add the whole extent
2579 * into urgent list. The extent may be being truncated or used, handle it
2582 int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
2583 struct osc_page *ops)
2585 struct osc_extent *ext = NULL;
2586 struct osc_object *obj = cl2osc(ops->ops_cl.cpl_obj);
2587 struct cl_page *cp = ops->ops_cl.cpl_page;
2588 pgoff_t index = osc_index(ops);
2589 struct osc_async_page *oap = &ops->ops_oap;
2590 bool unplug = false;
2594 osc_object_lock(obj);
2595 ext = osc_extent_lookup(obj, index);
2597 osc_extent_tree_dump(D_ERROR, obj);
2598 LASSERTF(0, "page index %lu is NOT covered.\n", index);
2601 switch (ext->oe_state) {
2604 CL_PAGE_DEBUG(D_ERROR, env, cp, "flush an in-rpc page?\n");
2608 /* If we know this extent is being written out, we should abort
2609 * so that the writer can make this page ready. Otherwise, there
2610 * exists a deadlock problem because other process can wait for
2611 * page writeback bit holding page lock; and meanwhile in
2612 * vvp_page_make_ready(), we need to grab page lock before
2613 * really sending the RPC. */
2615 /* race with truncate, page will be redirtied */
2617 /* The extent is active so we need to abort and let the caller
2618 * re-dirty the page. If we continued on here, and we were the
2619 * one making the extent active, we could deadlock waiting for
2620 * the page writeback to clear but it won't because the extent
2621 * is active and won't be written out. */
2622 GOTO(out, rc = -EAGAIN);
2627 rc = cl_page_prep(env, io, cp, CRT_WRITE);
2631 spin_lock(&oap->oap_lock);
2632 oap->oap_async_flags |= ASYNC_READY|ASYNC_URGENT;
2633 spin_unlock(&oap->oap_lock);
2635 if (memory_pressure_get())
2636 ext->oe_memalloc = 1;
2639 if (ext->oe_state == OES_CACHE) {
2640 OSC_EXTENT_DUMP(D_CACHE, ext,
2641 "flush page %p make it urgent.\n", oap);
2642 if (list_empty(&ext->oe_link))
2643 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2650 osc_object_unlock(obj);
2651 osc_extent_put(env, ext);
2653 osc_io_unplug_async(env, osc_cli(obj), obj);
2658 * this is called when a sync waiter receives an interruption. Its job is to
2659 * get the caller woken as soon as possible. If its page hasn't been put in an
2660 * rpc yet it can dequeue immediately. Otherwise it has to mark the rpc as
2661 * desiring interruption which will forcefully complete the rpc once the rpc
2664 int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops)
2666 struct osc_async_page *oap = &ops->ops_oap;
2667 struct osc_object *obj = oap->oap_obj;
2668 struct client_obd *cli = osc_cli(obj);
2669 struct osc_extent *ext;
2670 struct osc_extent *found = NULL;
2671 struct list_head *plist;
2672 pgoff_t index = osc_index(ops);
2677 LASSERT(!oap->oap_interrupted);
2678 oap->oap_interrupted = 1;
2680 /* Find out the caching extent */
2681 osc_object_lock(obj);
2682 if (oap->oap_cmd & OBD_BRW_WRITE) {
2683 plist = &obj->oo_urgent_exts;
2684 cmd = OBD_BRW_WRITE;
2686 plist = &obj->oo_reading_exts;
2689 list_for_each_entry(ext, plist, oe_link) {
2690 if (ext->oe_start <= index && ext->oe_end >= index) {
2691 LASSERT(ext->oe_state == OES_LOCK_DONE);
2692 /* For OES_LOCK_DONE state extent, it has already held
2693 * a refcount for RPC. */
2694 found = osc_extent_get(ext);
2698 if (found != NULL) {
2699 list_del_init(&found->oe_link);
2700 osc_update_pending(obj, cmd, -found->oe_nr_pages);
2701 osc_object_unlock(obj);
2703 osc_extent_finish(env, found, 0, -EINTR);
2704 osc_extent_put(env, found);
2707 osc_object_unlock(obj);
2708 /* ok, it's been put in an rpc. only one oap gets a request
2710 if (oap->oap_request != NULL) {
2711 ptlrpc_mark_interrupted(oap->oap_request);
2712 ptlrpcd_wake(oap->oap_request);
2713 ptlrpc_req_finished(oap->oap_request);
2714 oap->oap_request = NULL;
2718 osc_list_maint(cli, obj);
2722 int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
2723 struct list_head *list, int cmd, int brw_flags)
2725 struct client_obd *cli = osc_cli(obj);
2726 struct osc_extent *ext;
2727 struct osc_async_page *oap;
2729 int mppr = cli->cl_max_pages_per_rpc;
2730 bool can_merge = true;
2731 pgoff_t start = CL_PAGE_EOF;
2735 list_for_each_entry(oap, list, oap_pending_item) {
2736 struct osc_page *opg = oap2osc_page(oap);
2737 pgoff_t index = osc_index(opg);
2744 mppr <<= (page_count > mppr);
2746 if (unlikely(opg->ops_from > 0 || opg->ops_to < PAGE_SIZE))
2750 ext = osc_extent_alloc(obj);
2752 struct osc_async_page *tmp;
2754 list_for_each_entry_safe(oap, tmp, list, oap_pending_item) {
2755 list_del_init(&oap->oap_pending_item);
2756 osc_ap_completion(env, cli, oap, 0, -ENOMEM);
2761 ext->oe_rw = !!(cmd & OBD_BRW_READ);
2763 ext->oe_no_merge = !can_merge;
2765 ext->oe_start = start;
2766 ext->oe_end = ext->oe_max_end = end;
2768 ext->oe_srvlock = !!(brw_flags & OBD_BRW_SRVLOCK);
2769 ext->oe_nr_pages = page_count;
2770 ext->oe_mppr = mppr;
2771 list_splice_init(list, &ext->oe_pages);
2773 osc_object_lock(obj);
2774 /* Reuse the initial refcount for RPC, don't drop it */
2775 osc_extent_state_set(ext, OES_LOCK_DONE);
2776 if (cmd & OBD_BRW_WRITE) {
2777 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2778 osc_update_pending(obj, OBD_BRW_WRITE, page_count);
2780 list_add_tail(&ext->oe_link, &obj->oo_reading_exts);
2781 osc_update_pending(obj, OBD_BRW_READ, page_count);
2783 osc_object_unlock(obj);
2785 osc_io_unplug_async(env, cli, obj);
2790 * Called by osc_io_setattr_start() to freeze and destroy covering extents.
2792 int osc_cache_truncate_start(const struct lu_env *env, struct osc_object *obj,
2793 __u64 size, struct osc_extent **extp)
2795 struct client_obd *cli = osc_cli(obj);
2796 struct osc_extent *ext;
2797 struct osc_extent *waiting = NULL;
2799 struct list_head list = LIST_HEAD_INIT(list);
2804 /* pages with index greater or equal to index will be truncated. */
2805 index = cl_index(osc2cl(obj), size);
2806 partial = size > cl_offset(osc2cl(obj), index);
2809 osc_object_lock(obj);
2810 ext = osc_extent_search(obj, index);
2812 ext = first_extent(obj);
2813 else if (ext->oe_end < index)
2814 ext = next_extent(ext);
2815 while (ext != NULL) {
2816 EASSERT(ext->oe_state != OES_TRUNC, ext);
2818 if (ext->oe_state > OES_CACHE || ext->oe_urgent) {
2819 /* if ext is in urgent state, it means there must exist
2820 * a page already having been flushed by write_page().
2821 * We have to wait for this extent because we can't
2822 * truncate that page. */
2823 OSC_EXTENT_DUMP(D_CACHE, ext,
2824 "waiting for busy extent\n");
2825 waiting = osc_extent_get(ext);
2829 OSC_EXTENT_DUMP(D_CACHE, ext, "try to trunc:%llu.\n", size);
2831 osc_extent_get(ext);
2832 if (ext->oe_state == OES_ACTIVE) {
2833 /* though we grab inode mutex for write path, but we
2834 * release it before releasing extent(in osc_io_end()),
2835 * so there is a race window that an extent is still
2836 * in OES_ACTIVE when truncate starts. */
2837 LASSERT(!ext->oe_trunc_pending);
2838 ext->oe_trunc_pending = 1;
2840 EASSERT(ext->oe_state == OES_CACHE, ext);
2841 osc_extent_state_set(ext, OES_TRUNC);
2842 osc_update_pending(obj, OBD_BRW_WRITE,
2845 /* This extent could be on the full extents list, that's OK */
2846 EASSERT(!ext->oe_hp && !ext->oe_urgent, ext);
2847 if (!list_empty(&ext->oe_link))
2848 list_move_tail(&ext->oe_link, &list);
2850 list_add_tail(&ext->oe_link, &list);
2852 ext = next_extent(ext);
2854 osc_object_unlock(obj);
2856 osc_list_maint(cli, obj);
2858 while (!list_empty(&list)) {
2861 ext = list_entry(list.next, struct osc_extent, oe_link);
2862 list_del_init(&ext->oe_link);
2864 /* extent may be in OES_ACTIVE state because inode mutex
2865 * is released before osc_io_end() in file write case */
2866 if (ext->oe_state != OES_TRUNC)
2867 osc_extent_wait(env, ext, OES_TRUNC);
2869 rc = osc_extent_truncate(ext, index, partial);
2874 OSC_EXTENT_DUMP(D_ERROR, ext,
2875 "truncate error %d\n", rc);
2876 } else if (ext->oe_nr_pages == 0) {
2877 osc_extent_remove(ext);
2879 /* this must be an overlapped extent which means only
2880 * part of pages in this extent have been truncated.
2882 EASSERTF(ext->oe_start <= index, ext,
2883 "trunc index = %lu/%d.\n", index, partial);
2884 /* fix index to skip this partially truncated extent */
2885 index = ext->oe_end + 1;
2888 /* we need to hold this extent in OES_TRUNC state so
2889 * that no writeback will happen. This is to avoid
2891 * Only partial truncate can reach here, if @size is
2892 * not zero, the caller should provide a valid @extp. */
2893 LASSERT(*extp == NULL);
2894 *extp = osc_extent_get(ext);
2895 OSC_EXTENT_DUMP(D_CACHE, ext,
2896 "trunc at %llu\n", size);
2898 osc_extent_put(env, ext);
2900 if (waiting != NULL) {
2903 /* ignore the result of osc_extent_wait the write initiator
2904 * should take care of it. */
2905 rc = osc_extent_wait(env, waiting, OES_INV);
2907 OSC_EXTENT_DUMP(D_CACHE, waiting, "error: %d.\n", rc);
2909 osc_extent_put(env, waiting);
2915 EXPORT_SYMBOL(osc_cache_truncate_start);
2918 * Called after osc_io_setattr_end to add oio->oi_trunc back to cache.
2920 void osc_cache_truncate_end(const struct lu_env *env, struct osc_extent *ext)
2923 struct osc_object *obj = ext->oe_obj;
2924 bool unplug = false;
2926 EASSERT(ext->oe_nr_pages > 0, ext);
2927 EASSERT(ext->oe_state == OES_TRUNC, ext);
2928 EASSERT(!ext->oe_urgent, ext);
2930 OSC_EXTENT_DUMP(D_CACHE, ext, "trunc -> cache.\n");
2931 osc_object_lock(obj);
2932 osc_extent_state_set(ext, OES_CACHE);
2933 if (ext->oe_fsync_wait && !ext->oe_urgent) {
2935 list_move_tail(&ext->oe_link, &obj->oo_urgent_exts);
2938 osc_update_pending(obj, OBD_BRW_WRITE, ext->oe_nr_pages);
2939 osc_object_unlock(obj);
2940 osc_extent_put(env, ext);
2943 osc_io_unplug_async(env, osc_cli(obj), obj);
2948 * Wait for extents in a specific range to be written out.
2949 * The caller must have called osc_cache_writeback_range() to issue IO
2950 * otherwise it will take a long time for this function to finish.
2952 * Caller must hold inode_mutex , or cancel exclusive dlm lock so that
2953 * nobody else can dirty this range of file while we're waiting for
2954 * extents to be written.
2956 int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
2957 pgoff_t start, pgoff_t end)
2959 struct osc_extent *ext;
2960 pgoff_t index = start;
2965 osc_object_lock(obj);
2966 ext = osc_extent_search(obj, index);
2968 ext = first_extent(obj);
2969 else if (ext->oe_end < index)
2970 ext = next_extent(ext);
2971 while (ext != NULL) {
2974 if (ext->oe_start > end)
2977 if (!ext->oe_fsync_wait) {
2978 ext = next_extent(ext);
2982 EASSERT(ergo(ext->oe_state == OES_CACHE,
2983 ext->oe_hp || ext->oe_urgent), ext);
2984 EASSERT(ergo(ext->oe_state == OES_ACTIVE,
2985 !ext->oe_hp && ext->oe_urgent), ext);
2987 index = ext->oe_end + 1;
2988 osc_extent_get(ext);
2989 osc_object_unlock(obj);
2991 rc = osc_extent_wait(env, ext, OES_INV);
2994 osc_extent_put(env, ext);
2997 osc_object_unlock(obj);
2999 OSC_IO_DEBUG(obj, "sync file range.\n");
3002 EXPORT_SYMBOL(osc_cache_wait_range);
3005 * Called to write out a range of osc object.
3007 * @hp : should be set this is caused by lock cancel;
3008 * @discard: is set if dirty pages should be dropped - file will be deleted or
3009 * truncated, this implies there is no partially discarding extents.
3011 * Return how many pages will be issued, or error code if error occurred.
3013 int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
3014 pgoff_t start, pgoff_t end, int hp, int discard)
3016 struct osc_extent *ext;
3017 struct list_head discard_list = LIST_HEAD_INIT(discard_list);
3018 bool unplug = false;
3022 osc_object_lock(obj);
3023 ext = osc_extent_search(obj, start);
3025 ext = first_extent(obj);
3026 else if (ext->oe_end < start)
3027 ext = next_extent(ext);
3028 while (ext != NULL) {
3029 if (ext->oe_start > end)
3032 ext->oe_fsync_wait = 1;
3033 switch (ext->oe_state) {
3035 result += ext->oe_nr_pages;
3037 struct list_head *list = NULL;
3039 EASSERT(!ext->oe_hp, ext);
3041 list = &obj->oo_hp_exts;
3042 } else if (!ext->oe_urgent) {
3044 list = &obj->oo_urgent_exts;
3047 list_move_tail(&ext->oe_link, list);
3050 /* the only discarder is lock cancelling, so
3051 * [start, end] must contain this extent */
3052 EASSERT(ext->oe_start >= start &&
3053 ext->oe_max_end <= end, ext);
3054 osc_extent_state_set(ext, OES_LOCKING);
3055 ext->oe_owner = current;
3056 list_move_tail(&ext->oe_link,
3058 osc_update_pending(obj, OBD_BRW_WRITE,
3063 /* It's pretty bad to wait for ACTIVE extents, because
3064 * we don't know how long we will wait for it to be
3065 * flushed since it may be blocked at awaiting more
3066 * grants. We do this for the correctness of fsync. */
3067 LASSERT(hp == 0 && discard == 0);
3071 /* this extent is being truncated, can't do anything
3072 * for it now. it will be set to urgent after truncate
3073 * is finished in osc_cache_truncate_end(). */
3077 ext = next_extent(ext);
3079 osc_object_unlock(obj);
3081 LASSERT(ergo(!discard, list_empty(&discard_list)));
3082 if (!list_empty(&discard_list)) {
3083 struct osc_extent *tmp;
3086 osc_list_maint(osc_cli(obj), obj);
3087 list_for_each_entry_safe(ext, tmp, &discard_list, oe_link) {
3088 list_del_init(&ext->oe_link);
3089 EASSERT(ext->oe_state == OES_LOCKING, ext);
3091 /* Discard caching pages. We don't actually write this
3092 * extent out but we complete it as if we did. */
3093 rc = osc_extent_make_ready(env, ext);
3094 if (unlikely(rc < 0)) {
3095 OSC_EXTENT_DUMP(D_ERROR, ext,
3096 "make_ready returned %d\n", rc);
3101 /* finish the extent as if the pages were sent */
3102 osc_extent_finish(env, ext, 0, 0);
3107 osc_io_unplug(env, osc_cli(obj), obj);
3109 if (hp || discard) {
3111 rc = osc_cache_wait_range(env, obj, start, end);
3112 if (result >= 0 && rc < 0)
3116 OSC_IO_DEBUG(obj, "pageout [%lu, %lu], %d.\n", start, end, result);
3119 EXPORT_SYMBOL(osc_cache_writeback_range);
3122 * Returns a list of pages by a given [start, end] of \a obj.
3124 * \param resched If not NULL, then we give up before hogging CPU for too
3125 * long and set *resched = 1, in that case caller should implement a retry
3128 * Gang tree lookup (radix_tree_gang_lookup()) optimization is absolutely
3129 * crucial in the face of [offset, EOF] locks.
3131 * Return at least one page in @queue unless there is no covered page.
3133 int osc_page_gang_lookup(const struct lu_env *env, struct cl_io *io,
3134 struct osc_object *osc, pgoff_t start, pgoff_t end,
3135 osc_page_gang_cbt cb, void *cbdata)
3137 struct osc_page *ops;
3143 int res = CLP_GANG_OKAY;
3144 bool tree_lock = true;
3148 pvec = osc_env_info(env)->oti_pvec;
3149 spin_lock(&osc->oo_tree_lock);
3150 while ((nr = radix_tree_gang_lookup(&osc->oo_tree, pvec,
3151 idx, OTI_PVEC_SIZE)) > 0) {
3152 struct cl_page *page;
3153 bool end_of_region = false;
3155 for (i = 0, j = 0; i < nr; ++i) {
3159 idx = osc_index(ops);
3161 end_of_region = true;
3165 page = ops->ops_cl.cpl_page;
3166 LASSERT(page->cp_type == CPT_CACHEABLE);
3167 if (page->cp_state == CPS_FREEING)
3171 lu_ref_add_atomic(&page->cp_reference,
3172 "gang_lookup", current);
3178 * Here a delicate locking dance is performed. Current thread
3179 * holds a reference to a page, but has to own it before it
3180 * can be placed into queue. Owning implies waiting, so
3181 * radix-tree lock is to be released. After a wait one has to
3182 * check that pages weren't truncated (cl_page_own() returns
3183 * error in the latter case).
3185 spin_unlock(&osc->oo_tree_lock);
3188 for (i = 0; i < j; ++i) {
3190 if (res == CLP_GANG_OKAY)
3191 res = (*cb)(env, io, ops, cbdata);
3193 page = ops->ops_cl.cpl_page;
3194 lu_ref_del(&page->cp_reference, "gang_lookup", current);
3195 cl_page_put(env, page);
3197 if (nr < OTI_PVEC_SIZE || end_of_region)
3200 if (res == CLP_GANG_OKAY && need_resched())
3201 res = CLP_GANG_RESCHED;
3202 if (res != CLP_GANG_OKAY)
3205 spin_lock(&osc->oo_tree_lock);
3209 spin_unlock(&osc->oo_tree_lock);
3212 EXPORT_SYMBOL(osc_page_gang_lookup);
3215 * Check if page @page is covered by an extra lock or discard it.
3217 static int check_and_discard_cb(const struct lu_env *env, struct cl_io *io,
3218 struct osc_page *ops, void *cbdata)
3220 struct osc_thread_info *info = osc_env_info(env);
3221 struct osc_object *osc = cbdata;
3224 index = osc_index(ops);
3225 if (index >= info->oti_fn_index) {
3226 struct ldlm_lock *tmp;
3227 struct cl_page *page = ops->ops_cl.cpl_page;
3229 /* refresh non-overlapped index */
3230 tmp = osc_dlmlock_at_pgoff(env, osc, index,
3231 OSC_DAP_FL_TEST_LOCK);
3233 __u64 end = tmp->l_policy_data.l_extent.end;
3234 /* Cache the first-non-overlapped index so as to skip
3235 * all pages within [index, oti_fn_index). This is safe
3236 * because if tmp lock is canceled, it will discard
3238 info->oti_fn_index = cl_index(osc2cl(osc), end + 1);
3239 if (end == OBD_OBJECT_EOF)
3240 info->oti_fn_index = CL_PAGE_EOF;
3242 } else if (cl_page_own(env, io, page) == 0) {
3243 /* discard the page */
3244 cl_page_discard(env, io, page);
3245 cl_page_disown(env, io, page);
3247 LASSERT(page->cp_state == CPS_FREEING);
3251 info->oti_next_index = index + 1;
3252 return CLP_GANG_OKAY;
3255 int osc_discard_cb(const struct lu_env *env, struct cl_io *io,
3256 struct osc_page *ops, void *cbdata)
3258 struct osc_thread_info *info = osc_env_info(env);
3259 struct cl_page *page = ops->ops_cl.cpl_page;
3261 /* page is top page. */
3262 info->oti_next_index = osc_index(ops) + 1;
3263 if (cl_page_own(env, io, page) == 0) {
3264 if (!ergo(page->cp_type == CPT_CACHEABLE,
3265 !PageDirty(cl_page_vmpage(page))))
3266 CL_PAGE_DEBUG(D_ERROR, env, page,
3267 "discard dirty page?\n");
3269 /* discard the page */
3270 cl_page_discard(env, io, page);
3271 cl_page_disown(env, io, page);
3273 LASSERT(page->cp_state == CPS_FREEING);
3276 return CLP_GANG_OKAY;
3278 EXPORT_SYMBOL(osc_discard_cb);
3281 * Discard pages protected by the given lock. This function traverses radix
3282 * tree to find all covering pages and discard them. If a page is being covered
3283 * by other locks, it should remain in cache.
3285 * If error happens on any step, the process continues anyway (the reasoning
3286 * behind this being that lock cancellation cannot be delayed indefinitely).
3288 int osc_lock_discard_pages(const struct lu_env *env, struct osc_object *osc,
3289 pgoff_t start, pgoff_t end, bool discard)
3291 struct osc_thread_info *info = osc_env_info(env);
3292 struct cl_io *io = &info->oti_io;
3293 osc_page_gang_cbt cb;
3299 io->ci_obj = cl_object_top(osc2cl(osc));
3300 io->ci_ignore_layout = 1;
3301 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
3305 cb = discard ? osc_discard_cb : check_and_discard_cb;
3306 info->oti_fn_index = info->oti_next_index = start;
3308 res = osc_page_gang_lookup(env, io, osc,
3309 info->oti_next_index, end, cb, osc);
3310 if (info->oti_next_index > end)
3313 if (res == CLP_GANG_RESCHED)
3315 } while (res != CLP_GANG_OKAY);
3317 cl_io_fini(env, io);