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 "osc_cl_internal.h"
41 #include "osc_internal.h"
43 static int extent_debug; /* set it to be true for more debug */
45 static void osc_update_pending(struct osc_object *obj, int cmd, int delta);
46 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
47 enum osc_extent_state state);
48 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
49 struct osc_async_page *oap, int sent, int rc);
50 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
52 static int osc_refresh_count(const struct lu_env *env,
53 struct osc_async_page *oap, int cmd);
54 static int osc_io_unplug_async(const struct lu_env *env,
55 struct client_obd *cli, struct osc_object *osc);
56 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
57 unsigned int lost_grant, unsigned int dirty_grant);
59 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
60 const char *func, int line);
61 #define osc_extent_tree_dump(lvl, obj) \
62 osc_extent_tree_dump0(lvl, obj, __func__, __LINE__)
64 static void osc_unreserve_grant(struct client_obd *cli, unsigned int reserved,
71 /* ------------------ osc extent ------------------ */
72 static inline char *ext_flags(struct osc_extent *ext, char *flags)
75 *buf++ = ext->oe_rw ? 'r' : 'w';
88 if (ext->oe_trunc_pending)
90 if (ext->oe_fsync_wait)
96 static inline char list_empty_marker(struct list_head *list)
98 return list_empty(list) ? '-' : '+';
101 #define EXTSTR "[%lu -> %lu/%lu]"
102 #define EXTPARA(ext) (ext)->oe_start, (ext)->oe_end, (ext)->oe_max_end
103 static const char *oes_strings[] = {
104 "inv", "active", "cache", "locking", "lockdone", "rpc", "trunc", NULL };
106 #define OSC_EXTENT_DUMP(lvl, extent, fmt, ...) do { \
107 struct osc_extent *__ext = (extent); \
111 "extent %p@{" EXTSTR ", " \
112 "[%d|%d|%c|%s|%s|%p], [%d|%d|%c|%c|%p|%u|%p]} " fmt, \
113 /* ----- extent part 0 ----- */ \
114 __ext, EXTPARA(__ext), \
115 /* ----- part 1 ----- */ \
116 atomic_read(&__ext->oe_refc), \
117 atomic_read(&__ext->oe_users), \
118 list_empty_marker(&__ext->oe_link), \
119 oes_strings[__ext->oe_state], ext_flags(__ext, __buf), \
121 /* ----- part 2 ----- */ \
122 __ext->oe_grants, __ext->oe_nr_pages, \
123 list_empty_marker(&__ext->oe_pages), \
124 waitqueue_active(&__ext->oe_waitq) ? '+' : '-', \
125 __ext->oe_dlmlock, __ext->oe_mppr, __ext->oe_owner, \
126 /* ----- part 4 ----- */ \
128 if (lvl == D_ERROR && __ext->oe_dlmlock != NULL) \
129 LDLM_ERROR(__ext->oe_dlmlock, "extent: %p", __ext); \
131 LDLM_DEBUG(__ext->oe_dlmlock, "extent: %p", __ext); \
135 #define EASSERTF(expr, ext, fmt, args...) do { \
137 OSC_EXTENT_DUMP(D_ERROR, (ext), fmt, ##args); \
138 osc_extent_tree_dump(D_ERROR, (ext)->oe_obj); \
144 #define EASSERT(expr, ext) EASSERTF(expr, ext, "\n")
146 static inline struct osc_extent *rb_extent(struct rb_node *n)
151 return container_of(n, struct osc_extent, oe_node);
154 static inline struct osc_extent *next_extent(struct osc_extent *ext)
159 LASSERT(ext->oe_intree);
160 return rb_extent(rb_next(&ext->oe_node));
163 static inline struct osc_extent *prev_extent(struct osc_extent *ext)
168 LASSERT(ext->oe_intree);
169 return rb_extent(rb_prev(&ext->oe_node));
172 static inline struct osc_extent *first_extent(struct osc_object *obj)
174 return rb_extent(rb_first(&obj->oo_root));
177 /* object must be locked by caller. */
178 static int osc_extent_sanity_check0(struct osc_extent *ext,
179 const char *func, const int line)
181 struct osc_object *obj = ext->oe_obj;
182 struct osc_async_page *oap;
186 if (!osc_object_is_locked(obj))
189 if (ext->oe_state >= OES_STATE_MAX)
192 if (atomic_read(&ext->oe_refc) <= 0)
195 if (atomic_read(&ext->oe_refc) < atomic_read(&ext->oe_users))
198 switch (ext->oe_state) {
200 if (ext->oe_nr_pages > 0 || !list_empty(&ext->oe_pages))
205 if (atomic_read(&ext->oe_users) == 0)
209 if (ext->oe_fsync_wait && !ext->oe_urgent)
213 if (ext->oe_grants == 0)
215 if (ext->oe_fsync_wait && !ext->oe_urgent && !ext->oe_hp)
218 if (atomic_read(&ext->oe_users) > 0)
222 if (ext->oe_max_end < ext->oe_end || ext->oe_end < ext->oe_start)
225 if (ext->oe_sync && ext->oe_grants > 0)
228 if (ext->oe_dlmlock != NULL && !ldlm_is_failed(ext->oe_dlmlock)) {
229 struct ldlm_extent *extent;
231 extent = &ext->oe_dlmlock->l_policy_data.l_extent;
232 if (!(extent->start <= cl_offset(osc2cl(obj), ext->oe_start) &&
233 extent->end >= cl_offset(osc2cl(obj), ext->oe_max_end)))
236 if (!(ext->oe_dlmlock->l_granted_mode & (LCK_PW | LCK_GROUP)))
240 if (ext->oe_nr_pages > ext->oe_mppr)
243 /* Do not verify page list if extent is in RPC. This is because an
244 * in-RPC extent is supposed to be exclusively accessible w/o lock. */
245 if (ext->oe_state > OES_CACHE)
252 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
253 pgoff_t index = osc_index(oap2osc(oap));
255 if (index > ext->oe_end || index < ext->oe_start)
258 if (page_count != ext->oe_nr_pages)
263 OSC_EXTENT_DUMP(D_ERROR, ext,
264 "%s:%d sanity check %p failed with rc = %d\n",
265 func, line, ext, rc);
269 #define sanity_check_nolock(ext) \
270 osc_extent_sanity_check0(ext, __func__, __LINE__)
272 #define sanity_check(ext) ({ \
274 osc_object_lock((ext)->oe_obj); \
275 __res = sanity_check_nolock(ext); \
276 osc_object_unlock((ext)->oe_obj); \
282 * sanity check - to make sure there is no overlapped extent in the tree.
284 static int osc_extent_is_overlapped(struct osc_object *obj,
285 struct osc_extent *ext)
287 struct osc_extent *tmp;
289 LASSERT(osc_object_is_locked(obj));
294 for (tmp = first_extent(obj); tmp != NULL; tmp = next_extent(tmp)) {
297 if (tmp->oe_end >= ext->oe_start &&
298 tmp->oe_start <= ext->oe_end)
304 static void osc_extent_state_set(struct osc_extent *ext, int state)
306 LASSERT(osc_object_is_locked(ext->oe_obj));
307 LASSERT(state >= OES_INV && state < OES_STATE_MAX);
309 /* Never try to sanity check a state changing extent :-) */
310 /* LASSERT(sanity_check_nolock(ext) == 0); */
312 /* TODO: validate the state machine */
313 ext->oe_state = state;
314 wake_up_all(&ext->oe_waitq);
317 static struct osc_extent *osc_extent_alloc(struct osc_object *obj)
319 struct osc_extent *ext;
321 OBD_SLAB_ALLOC_PTR_GFP(ext, osc_extent_kmem, GFP_NOFS);
325 RB_CLEAR_NODE(&ext->oe_node);
327 cl_object_get(osc2cl(obj));
328 atomic_set(&ext->oe_refc, 1);
329 atomic_set(&ext->oe_users, 0);
330 INIT_LIST_HEAD(&ext->oe_link);
331 ext->oe_state = OES_INV;
332 INIT_LIST_HEAD(&ext->oe_pages);
333 init_waitqueue_head(&ext->oe_waitq);
334 ext->oe_dlmlock = NULL;
339 static void osc_extent_free(struct osc_extent *ext)
341 OBD_SLAB_FREE_PTR(ext, osc_extent_kmem);
344 static struct osc_extent *osc_extent_get(struct osc_extent *ext)
346 LASSERT(atomic_read(&ext->oe_refc) >= 0);
347 atomic_inc(&ext->oe_refc);
351 static void osc_extent_put(const struct lu_env *env, struct osc_extent *ext)
353 LASSERT(atomic_read(&ext->oe_refc) > 0);
354 if (atomic_dec_and_test(&ext->oe_refc)) {
355 LASSERT(list_empty(&ext->oe_link));
356 LASSERT(atomic_read(&ext->oe_users) == 0);
357 LASSERT(ext->oe_state == OES_INV);
358 LASSERT(!ext->oe_intree);
360 if (ext->oe_dlmlock != NULL) {
361 lu_ref_add(&ext->oe_dlmlock->l_reference,
363 LDLM_LOCK_PUT(ext->oe_dlmlock);
364 ext->oe_dlmlock = NULL;
366 cl_object_put(env, osc2cl(ext->oe_obj));
367 osc_extent_free(ext);
372 * osc_extent_put_trust() is a special version of osc_extent_put() when
373 * it's known that the caller is not the last user. This is to address the
374 * problem of lacking of lu_env ;-).
376 static void osc_extent_put_trust(struct osc_extent *ext)
378 LASSERT(atomic_read(&ext->oe_refc) > 1);
379 LASSERT(osc_object_is_locked(ext->oe_obj));
380 atomic_dec(&ext->oe_refc);
384 * Return the extent which includes pgoff @index, or return the greatest
385 * previous extent in the tree.
387 static struct osc_extent *osc_extent_search(struct osc_object *obj,
390 struct rb_node *n = obj->oo_root.rb_node;
391 struct osc_extent *tmp, *p = NULL;
393 LASSERT(osc_object_is_locked(obj));
396 if (index < tmp->oe_start) {
398 } else if (index > tmp->oe_end) {
409 * Return the extent covering @index, otherwise return NULL.
410 * caller must have held object lock.
412 static struct osc_extent *osc_extent_lookup(struct osc_object *obj,
415 struct osc_extent *ext;
417 ext = osc_extent_search(obj, index);
418 if (ext != NULL && ext->oe_start <= index && index <= ext->oe_end)
419 return osc_extent_get(ext);
423 /* caller must have held object lock. */
424 static void osc_extent_insert(struct osc_object *obj, struct osc_extent *ext)
426 struct rb_node **n = &obj->oo_root.rb_node;
427 struct rb_node *parent = NULL;
428 struct osc_extent *tmp;
430 LASSERT(ext->oe_intree == 0);
431 LASSERT(ext->oe_obj == obj);
432 LASSERT(osc_object_is_locked(obj));
437 if (ext->oe_end < tmp->oe_start)
439 else if (ext->oe_start > tmp->oe_end)
442 EASSERTF(0, tmp, EXTSTR"\n", EXTPARA(ext));
444 rb_link_node(&ext->oe_node, parent, n);
445 rb_insert_color(&ext->oe_node, &obj->oo_root);
450 /* caller must have held object lock. */
451 static void osc_extent_erase(struct osc_extent *ext)
453 struct osc_object *obj = ext->oe_obj;
454 LASSERT(osc_object_is_locked(obj));
455 if (ext->oe_intree) {
456 rb_erase(&ext->oe_node, &obj->oo_root);
458 /* rbtree held a refcount */
459 osc_extent_put_trust(ext);
463 static struct osc_extent *osc_extent_hold(struct osc_extent *ext)
465 struct osc_object *obj = ext->oe_obj;
467 LASSERT(osc_object_is_locked(obj));
468 LASSERT(ext->oe_state == OES_ACTIVE || ext->oe_state == OES_CACHE);
469 if (ext->oe_state == OES_CACHE) {
470 osc_extent_state_set(ext, OES_ACTIVE);
471 osc_update_pending(obj, OBD_BRW_WRITE, -ext->oe_nr_pages);
473 atomic_inc(&ext->oe_users);
474 list_del_init(&ext->oe_link);
475 return osc_extent_get(ext);
478 static void __osc_extent_remove(struct osc_extent *ext)
480 LASSERT(osc_object_is_locked(ext->oe_obj));
481 LASSERT(list_empty(&ext->oe_pages));
482 osc_extent_erase(ext);
483 list_del_init(&ext->oe_link);
484 osc_extent_state_set(ext, OES_INV);
485 OSC_EXTENT_DUMP(D_CACHE, ext, "destroyed.\n");
488 static void osc_extent_remove(struct osc_extent *ext)
490 struct osc_object *obj = ext->oe_obj;
492 osc_object_lock(obj);
493 __osc_extent_remove(ext);
494 osc_object_unlock(obj);
498 * This function is used to merge extents to get better performance. It checks
499 * if @cur and @victim are contiguous at block level.
501 static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
502 struct osc_extent *victim)
504 struct osc_object *obj = cur->oe_obj;
505 struct client_obd *cli = osc_cli(obj);
510 LASSERT(cur->oe_state == OES_CACHE);
511 LASSERT(osc_object_is_locked(obj));
515 if (victim->oe_state != OES_CACHE || victim->oe_fsync_wait)
518 if (cur->oe_max_end != victim->oe_max_end)
521 LASSERT(cur->oe_dlmlock == victim->oe_dlmlock);
522 ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_SHIFT;
523 chunk_start = cur->oe_start >> ppc_bits;
524 chunk_end = cur->oe_end >> ppc_bits;
525 if (chunk_start != (victim->oe_end >> ppc_bits) + 1 &&
526 chunk_end + 1 != victim->oe_start >> ppc_bits)
529 /* overall extent size should not exceed the max supported limit
530 * reported by the server */
531 if (cur->oe_end - cur->oe_start + 1 +
532 victim->oe_end - victim->oe_start + 1 > cli->cl_max_extent_pages)
535 OSC_EXTENT_DUMP(D_CACHE, victim, "will be merged by %p.\n", cur);
537 cur->oe_start = min(cur->oe_start, victim->oe_start);
538 cur->oe_end = max(cur->oe_end, victim->oe_end);
539 /* per-extent tax should be accounted only once for the whole extent */
540 cur->oe_grants += victim->oe_grants - cli->cl_grant_extent_tax;
541 cur->oe_nr_pages += victim->oe_nr_pages;
542 /* only the following bits are needed to merge */
543 cur->oe_urgent |= victim->oe_urgent;
544 cur->oe_memalloc |= victim->oe_memalloc;
545 list_splice_init(&victim->oe_pages, &cur->oe_pages);
546 list_del_init(&victim->oe_link);
547 victim->oe_nr_pages = 0;
549 osc_extent_get(victim);
550 __osc_extent_remove(victim);
551 osc_extent_put(env, victim);
553 OSC_EXTENT_DUMP(D_CACHE, cur, "after merging %p.\n", victim);
558 * Drop user count of osc_extent, and unplug IO asynchronously.
560 int osc_extent_release(const struct lu_env *env, struct osc_extent *ext)
562 struct osc_object *obj = ext->oe_obj;
563 struct client_obd *cli = osc_cli(obj);
567 LASSERT(atomic_read(&ext->oe_users) > 0);
568 LASSERT(sanity_check(ext) == 0);
569 LASSERT(ext->oe_grants > 0);
571 if (atomic_dec_and_lock(&ext->oe_users, &obj->oo_lock)) {
572 LASSERT(ext->oe_state == OES_ACTIVE);
573 if (ext->oe_trunc_pending) {
574 /* a truncate process is waiting for this extent.
575 * This may happen due to a race, check
576 * osc_cache_truncate_start(). */
577 osc_extent_state_set(ext, OES_TRUNC);
578 ext->oe_trunc_pending = 0;
582 osc_extent_state_set(ext, OES_CACHE);
583 osc_update_pending(obj, OBD_BRW_WRITE,
586 /* try to merge the previous and next extent. */
587 if (osc_extent_merge(env, ext, prev_extent(ext)) == 0)
588 grant += cli->cl_grant_extent_tax;
589 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
590 grant += cli->cl_grant_extent_tax;
592 osc_unreserve_grant(cli, 0, grant);
595 list_move_tail(&ext->oe_link,
596 &obj->oo_urgent_exts);
597 else if (ext->oe_nr_pages == ext->oe_mppr) {
598 list_move_tail(&ext->oe_link,
602 osc_object_unlock(obj);
604 osc_io_unplug_async(env, cli, obj);
606 osc_extent_put(env, ext);
610 static inline int overlapped(struct osc_extent *ex1, struct osc_extent *ex2)
612 return !(ex1->oe_end < ex2->oe_start || ex2->oe_end < ex1->oe_start);
616 * Find or create an extent which includes @index, core function to manage
619 static struct osc_extent *osc_extent_find(const struct lu_env *env,
620 struct osc_object *obj, pgoff_t index,
621 unsigned int *grants)
623 struct client_obd *cli = osc_cli(obj);
624 struct osc_lock *olck;
625 struct cl_lock_descr *descr;
626 struct osc_extent *cur;
627 struct osc_extent *ext;
628 struct osc_extent *conflict = NULL;
629 struct osc_extent *found = NULL;
632 unsigned int max_pages; /* max_pages_per_rpc */
633 unsigned int chunksize;
634 int ppc_bits; /* pages per chunk bits */
639 cur = osc_extent_alloc(obj);
641 RETURN(ERR_PTR(-ENOMEM));
643 olck = osc_env_io(env)->oi_write_osclock;
644 LASSERTF(olck != NULL, "page %lu is not covered by lock\n", index);
645 LASSERT(olck->ols_state == OLS_GRANTED);
647 descr = &olck->ols_cl.cls_lock->cll_descr;
648 LASSERT(descr->cld_mode >= CLM_WRITE);
650 LASSERTF(cli->cl_chunkbits >= PAGE_SHIFT,
651 "chunkbits: %u\n", cli->cl_chunkbits);
652 ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
653 chunk_mask = ~((1 << ppc_bits) - 1);
654 chunksize = 1 << cli->cl_chunkbits;
655 chunk = index >> ppc_bits;
657 /* align end to RPC edge. */
658 max_pages = cli->cl_max_pages_per_rpc;
659 if ((max_pages & ~chunk_mask) != 0) {
660 CERROR("max_pages: %#x chunkbits: %u chunk_mask: %#lx\n",
661 max_pages, cli->cl_chunkbits, chunk_mask);
662 RETURN(ERR_PTR(-EINVAL));
664 max_end = index - (index % max_pages) + max_pages - 1;
665 max_end = min_t(pgoff_t, max_end, descr->cld_end);
667 /* initialize new extent by parameters so far */
668 cur->oe_max_end = max_end;
669 cur->oe_start = index & chunk_mask;
670 cur->oe_end = ((index + ~chunk_mask + 1) & chunk_mask) - 1;
671 if (cur->oe_start < descr->cld_start)
672 cur->oe_start = descr->cld_start;
673 if (cur->oe_end > max_end)
674 cur->oe_end = max_end;
676 cur->oe_mppr = max_pages;
677 if (olck->ols_dlmlock != NULL) {
678 LASSERT(olck->ols_hold);
679 cur->oe_dlmlock = LDLM_LOCK_GET(olck->ols_dlmlock);
680 lu_ref_add(&olck->ols_dlmlock->l_reference, "osc_extent", cur);
683 /* grants has been allocated by caller */
684 LASSERTF(*grants >= chunksize + cli->cl_grant_extent_tax,
685 "%u/%u/%u.\n", *grants, chunksize, cli->cl_grant_extent_tax);
686 LASSERTF((max_end - cur->oe_start) < max_pages, EXTSTR"\n",
690 osc_object_lock(obj);
691 ext = osc_extent_search(obj, cur->oe_start);
693 ext = first_extent(obj);
694 while (ext != NULL) {
695 pgoff_t ext_chk_start = ext->oe_start >> ppc_bits;
696 pgoff_t ext_chk_end = ext->oe_end >> ppc_bits;
698 LASSERT(sanity_check_nolock(ext) == 0);
699 if (chunk > ext_chk_end + 1)
702 /* if covering by different locks, no chance to match */
703 if (olck->ols_dlmlock != ext->oe_dlmlock) {
704 EASSERTF(!overlapped(ext, cur), ext,
705 EXTSTR"\n", EXTPARA(cur));
707 ext = next_extent(ext);
711 /* discontiguous chunks? */
712 if (chunk + 1 < ext_chk_start) {
713 ext = next_extent(ext);
717 /* ok, from now on, ext and cur have these attrs:
718 * 1. covered by the same lock
719 * 2. contiguous at chunk level or overlapping. */
721 if (overlapped(ext, cur)) {
722 /* cur is the minimum unit, so overlapping means
724 EASSERTF((ext->oe_start <= cur->oe_start &&
725 ext->oe_end >= cur->oe_end),
726 ext, EXTSTR"\n", EXTPARA(cur));
728 if (ext->oe_state > OES_CACHE || ext->oe_fsync_wait) {
729 /* for simplicity, we wait for this extent to
730 * finish before going forward. */
731 conflict = osc_extent_get(ext);
735 found = osc_extent_hold(ext);
739 /* non-overlapped extent */
740 if (ext->oe_state != OES_CACHE || ext->oe_fsync_wait) {
741 /* we can't do anything for a non OES_CACHE extent, or
742 * if there is someone waiting for this extent to be
743 * flushed, try next one. */
744 ext = next_extent(ext);
748 /* check if they belong to the same rpc slot before trying to
749 * merge. the extents are not overlapped and contiguous at
750 * chunk level to get here. */
751 if (ext->oe_max_end != max_end) {
752 /* if they don't belong to the same RPC slot or
753 * max_pages_per_rpc has ever changed, do not merge. */
754 ext = next_extent(ext);
758 /* check whether maximum extent size will be hit */
759 if ((ext_chk_end - ext_chk_start + 1 + 1) << ppc_bits >
760 cli->cl_max_extent_pages) {
761 ext = next_extent(ext);
765 /* it's required that an extent must be contiguous at chunk
766 * level so that we know the whole extent is covered by grant
767 * (the pages in the extent are NOT required to be contiguous).
768 * Otherwise, it will be too much difficult to know which
769 * chunks have grants allocated. */
771 /* try to do front merge - extend ext's start */
772 if (chunk + 1 == ext_chk_start) {
773 /* ext must be chunk size aligned */
774 EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
776 /* pull ext's start back to cover cur */
777 ext->oe_start = cur->oe_start;
778 ext->oe_grants += chunksize;
779 LASSERT(*grants >= chunksize);
780 *grants -= chunksize;
782 found = osc_extent_hold(ext);
783 } else if (chunk == ext_chk_end + 1) {
785 ext->oe_end = cur->oe_end;
786 ext->oe_grants += chunksize;
787 LASSERT(*grants >= chunksize);
788 *grants -= chunksize;
790 /* try to merge with the next one because we just fill
792 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
793 /* we can save extent tax from next extent */
794 *grants += cli->cl_grant_extent_tax;
796 found = osc_extent_hold(ext);
801 ext = next_extent(ext);
804 osc_extent_tree_dump(D_CACHE, obj);
806 LASSERT(conflict == NULL);
807 if (!IS_ERR(found)) {
808 LASSERT(found->oe_dlmlock == cur->oe_dlmlock);
809 OSC_EXTENT_DUMP(D_CACHE, found,
810 "found caching ext for %lu.\n", index);
812 } else if (conflict == NULL) {
813 /* create a new extent */
814 EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
815 cur->oe_grants = chunksize + cli->cl_grant_extent_tax;
816 LASSERT(*grants >= cur->oe_grants);
817 *grants -= cur->oe_grants;
819 cur->oe_state = OES_CACHE;
820 found = osc_extent_hold(cur);
821 osc_extent_insert(obj, cur);
822 OSC_EXTENT_DUMP(D_CACHE, cur, "add into tree %lu/%lu.\n",
823 index, descr->cld_end);
825 osc_object_unlock(obj);
827 if (conflict != NULL) {
828 LASSERT(found == NULL);
830 /* waiting for IO to finish. Please notice that it's impossible
831 * to be an OES_TRUNC extent. */
832 rc = osc_extent_wait(env, conflict, OES_INV);
833 osc_extent_put(env, conflict);
836 GOTO(out, found = ERR_PTR(rc));
843 osc_extent_put(env, cur);
848 * Called when IO is finished to an extent.
850 int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
853 struct client_obd *cli = osc_cli(ext->oe_obj);
854 struct osc_async_page *oap;
855 struct osc_async_page *tmp;
856 int nr_pages = ext->oe_nr_pages;
858 int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
863 OSC_EXTENT_DUMP(D_CACHE, ext, "extent finished.\n");
865 ext->oe_rc = rc ?: ext->oe_nr_pages;
866 EASSERT(ergo(rc == 0, ext->oe_state == OES_RPC), ext);
868 osc_lru_add_batch(cli, &ext->oe_pages);
869 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
871 list_del_init(&oap->oap_rpc_item);
872 list_del_init(&oap->oap_pending_item);
873 if (last_off <= oap->oap_obj_off) {
874 last_off = oap->oap_obj_off;
875 last_count = oap->oap_count;
879 osc_ap_completion(env, cli, oap, sent, rc);
881 EASSERT(ext->oe_nr_pages == 0, ext);
884 lost_grant = ext->oe_grants;
885 } else if (blocksize < PAGE_SIZE &&
886 last_count != PAGE_SIZE) {
887 /* For short writes we shouldn't count parts of pages that
888 * span a whole chunk on the OST side, or our accounting goes
889 * wrong. Should match the code in filter_grant_check. */
890 int offset = last_off & ~PAGE_MASK;
891 int count = last_count + (offset & (blocksize - 1));
892 int end = (offset + last_count) & (blocksize - 1);
894 count += blocksize - end;
896 lost_grant = PAGE_SIZE - count;
898 if (ext->oe_grants > 0)
899 osc_free_grant(cli, nr_pages, lost_grant, ext->oe_grants);
901 osc_extent_remove(ext);
902 /* put the refcount for RPC */
903 osc_extent_put(env, ext);
907 static int extent_wait_cb(struct osc_extent *ext, enum osc_extent_state state)
911 osc_object_lock(ext->oe_obj);
912 ret = ext->oe_state == state;
913 osc_object_unlock(ext->oe_obj);
919 * Wait for the extent's state to become @state.
921 static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
922 enum osc_extent_state state)
924 struct osc_object *obj = ext->oe_obj;
925 struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(600), NULL,
926 LWI_ON_SIGNAL_NOOP, NULL);
930 osc_object_lock(obj);
931 LASSERT(sanity_check_nolock(ext) == 0);
932 /* `Kick' this extent only if the caller is waiting for it to be
934 if (state == OES_INV && !ext->oe_urgent && !ext->oe_hp) {
935 if (ext->oe_state == OES_ACTIVE) {
937 } else if (ext->oe_state == OES_CACHE) {
939 osc_extent_hold(ext);
943 osc_object_unlock(obj);
945 osc_extent_release(env, ext);
947 /* wait for the extent until its state becomes @state */
948 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state), &lwi);
949 if (rc == -ETIMEDOUT) {
950 OSC_EXTENT_DUMP(D_ERROR, ext,
951 "%s: wait ext to %u timedout, recovery in progress?\n",
952 cli_name(osc_cli(obj)), state);
954 lwi = LWI_INTR(NULL, NULL);
955 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state),
958 if (rc == 0 && ext->oe_rc < 0)
964 * Discard pages with index greater than @size. If @ext is overlapped with
965 * @size, then partial truncate happens.
967 static int osc_extent_truncate(struct osc_extent *ext, pgoff_t trunc_index,
972 struct osc_object *obj = ext->oe_obj;
973 struct client_obd *cli = osc_cli(obj);
974 struct osc_async_page *oap;
975 struct osc_async_page *tmp;
976 int pages_in_chunk = 0;
977 int ppc_bits = cli->cl_chunkbits -
979 __u64 trunc_chunk = trunc_index >> ppc_bits;
986 LASSERT(sanity_check(ext) == 0);
987 LASSERT(ext->oe_state == OES_TRUNC);
988 LASSERT(!ext->oe_urgent);
990 /* Request new lu_env.
991 * We can't use that env from osc_cache_truncate_start() because
992 * it's from lov_io_sub and not fully initialized. */
993 env = cl_env_get(&refcheck);
995 RETURN(PTR_ERR(env));
997 io = &osc_env_info(env)->oti_io;
998 io->ci_obj = cl_object_top(osc2cl(obj));
999 io->ci_ignore_layout = 1;
1000 rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
1004 /* discard all pages with index greater than trunc_index */
1005 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
1007 pgoff_t index = osc_index(oap2osc(oap));
1008 struct cl_page *page = oap2cl_page(oap);
1010 LASSERT(list_empty(&oap->oap_rpc_item));
1012 /* only discard the pages with their index greater than
1013 * trunc_index, and ... */
1014 if (index < trunc_index ||
1015 (index == trunc_index && partial)) {
1016 /* accounting how many pages remaining in the chunk
1017 * so that we can calculate grants correctly. */
1018 if (index >> ppc_bits == trunc_chunk)
1023 list_del_init(&oap->oap_pending_item);
1026 lu_ref_add(&page->cp_reference, "truncate", current);
1028 if (cl_page_own(env, io, page) == 0) {
1029 cl_page_discard(env, io, page);
1030 cl_page_disown(env, io, page);
1032 LASSERT(page->cp_state == CPS_FREEING);
1036 lu_ref_del(&page->cp_reference, "truncate", current);
1037 cl_page_put(env, page);
1042 EASSERTF(ergo(ext->oe_start >= trunc_index + !!partial,
1043 ext->oe_nr_pages == 0),
1044 ext, "trunc_index %lu, partial %d\n", trunc_index, partial);
1046 osc_object_lock(obj);
1047 if (ext->oe_nr_pages == 0) {
1048 LASSERT(pages_in_chunk == 0);
1049 grants = ext->oe_grants;
1051 } else { /* calculate how many grants we can free */
1052 int chunks = (ext->oe_end >> ppc_bits) - trunc_chunk;
1056 /* if there is no pages in this chunk, we can also free grants
1057 * for the last chunk */
1058 if (pages_in_chunk == 0) {
1059 /* if this is the 1st chunk and no pages in this chunk,
1060 * ext->oe_nr_pages must be zero, so we should be in
1061 * the other if-clause. */
1062 LASSERT(trunc_chunk > 0);
1067 /* this is what we can free from this extent */
1068 grants = chunks << cli->cl_chunkbits;
1069 ext->oe_grants -= grants;
1070 last_index = ((trunc_chunk + 1) << ppc_bits) - 1;
1071 ext->oe_end = min(last_index, ext->oe_max_end);
1072 LASSERT(ext->oe_end >= ext->oe_start);
1073 LASSERT(ext->oe_grants > 0);
1075 osc_object_unlock(obj);
1077 if (grants > 0 || nr_pages > 0)
1078 osc_free_grant(cli, nr_pages, grants, grants);
1081 cl_io_fini(env, io);
1082 cl_env_put(env, &refcheck);
1087 * This function is used to make the extent prepared for transfer.
1088 * A race with flusing page - ll_writepage() has to be handled cautiously.
1090 static int osc_extent_make_ready(const struct lu_env *env,
1091 struct osc_extent *ext)
1093 struct osc_async_page *oap;
1094 struct osc_async_page *last = NULL;
1095 struct osc_object *obj = ext->oe_obj;
1096 unsigned int page_count = 0;
1100 /* we're going to grab page lock, so object lock must not be taken. */
1101 LASSERT(sanity_check(ext) == 0);
1102 /* in locking state, any process should not touch this extent. */
1103 EASSERT(ext->oe_state == OES_LOCKING, ext);
1104 EASSERT(ext->oe_owner != NULL, ext);
1106 OSC_EXTENT_DUMP(D_CACHE, ext, "make ready\n");
1108 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1110 if (last == NULL || last->oap_obj_off < oap->oap_obj_off)
1113 /* checking ASYNC_READY is race safe */
1114 if ((oap->oap_async_flags & ASYNC_READY) != 0)
1117 rc = osc_make_ready(env, oap, OBD_BRW_WRITE);
1120 spin_lock(&oap->oap_lock);
1121 oap->oap_async_flags |= ASYNC_READY;
1122 spin_unlock(&oap->oap_lock);
1125 LASSERT((oap->oap_async_flags & ASYNC_READY) != 0);
1128 LASSERTF(0, "unknown return code: %d\n", rc);
1132 LASSERT(page_count == ext->oe_nr_pages);
1133 LASSERT(last != NULL);
1134 /* the last page is the only one we need to refresh its count by
1135 * the size of file. */
1136 if (!(last->oap_async_flags & ASYNC_COUNT_STABLE)) {
1137 int last_oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE);
1138 LASSERT(last_oap_count > 0);
1139 LASSERT(last->oap_page_off + last_oap_count <= PAGE_SIZE);
1140 last->oap_count = last_oap_count;
1141 spin_lock(&last->oap_lock);
1142 last->oap_async_flags |= ASYNC_COUNT_STABLE;
1143 spin_unlock(&last->oap_lock);
1146 /* for the rest of pages, we don't need to call osf_refresh_count()
1147 * because it's known they are not the last page */
1148 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1149 if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
1150 oap->oap_count = PAGE_SIZE - oap->oap_page_off;
1151 spin_lock(&oap->oap_lock);
1152 oap->oap_async_flags |= ASYNC_COUNT_STABLE;
1153 spin_unlock(&oap->oap_lock);
1157 osc_object_lock(obj);
1158 osc_extent_state_set(ext, OES_RPC);
1159 osc_object_unlock(obj);
1160 /* get a refcount for RPC. */
1161 osc_extent_get(ext);
1167 * Quick and simple version of osc_extent_find(). This function is frequently
1168 * called to expand the extent for the same IO. To expand the extent, the
1169 * page index must be in the same or next chunk of ext->oe_end.
1171 static int osc_extent_expand(struct osc_extent *ext, pgoff_t index,
1172 unsigned int *grants)
1174 struct osc_object *obj = ext->oe_obj;
1175 struct client_obd *cli = osc_cli(obj);
1176 struct osc_extent *next;
1177 int ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
1178 pgoff_t chunk = index >> ppc_bits;
1181 unsigned int chunksize = 1 << cli->cl_chunkbits;
1185 LASSERT(ext->oe_max_end >= index && ext->oe_start <= index);
1186 osc_object_lock(obj);
1187 LASSERT(sanity_check_nolock(ext) == 0);
1188 end_chunk = ext->oe_end >> ppc_bits;
1189 if (chunk > end_chunk + 1)
1190 GOTO(out, rc = -ERANGE);
1192 if (end_chunk >= chunk)
1195 LASSERT(end_chunk + 1 == chunk);
1197 /* try to expand this extent to cover @index */
1198 end_index = min(ext->oe_max_end, ((chunk + 1) << ppc_bits) - 1);
1200 /* don't go over the maximum extent size reported by server */
1201 if (end_index - ext->oe_start + 1 > cli->cl_max_extent_pages)
1202 GOTO(out, rc = -ERANGE);
1204 next = next_extent(ext);
1205 if (next != NULL && next->oe_start <= end_index)
1206 /* complex mode - overlapped with the next extent,
1207 * this case will be handled by osc_extent_find() */
1208 GOTO(out, rc = -EAGAIN);
1210 ext->oe_end = end_index;
1211 ext->oe_grants += chunksize;
1212 LASSERT(*grants >= chunksize);
1213 *grants -= chunksize;
1214 EASSERTF(osc_extent_is_overlapped(obj, ext) == 0, ext,
1215 "overlapped after expanding for %lu.\n", index);
1219 osc_object_unlock(obj);
1223 static void osc_extent_tree_dump0(int level, struct osc_object *obj,
1224 const char *func, int line)
1226 struct osc_extent *ext;
1229 CDEBUG(level, "Dump object %p extents at %s:%d, mppr: %u.\n",
1230 obj, func, line, osc_cli(obj)->cl_max_pages_per_rpc);
1232 /* osc_object_lock(obj); */
1234 for (ext = first_extent(obj); ext != NULL; ext = next_extent(ext))
1235 OSC_EXTENT_DUMP(level, ext, "in tree %d.\n", cnt++);
1238 list_for_each_entry(ext, &obj->oo_hp_exts, oe_link)
1239 OSC_EXTENT_DUMP(level, ext, "hp %d.\n", cnt++);
1242 list_for_each_entry(ext, &obj->oo_urgent_exts, oe_link)
1243 OSC_EXTENT_DUMP(level, ext, "urgent %d.\n", cnt++);
1246 list_for_each_entry(ext, &obj->oo_reading_exts, oe_link)
1247 OSC_EXTENT_DUMP(level, ext, "reading %d.\n", cnt++);
1248 /* osc_object_unlock(obj); */
1251 /* ------------------ osc extent end ------------------ */
1253 static inline int osc_is_ready(struct osc_object *osc)
1255 return !list_empty(&osc->oo_ready_item) ||
1256 !list_empty(&osc->oo_hp_ready_item);
1259 #define OSC_IO_DEBUG(OSC, STR, args...) \
1260 CDEBUG(D_CACHE, "obj %p ready %d|%c|%c wr %d|%c|%c rd %d|%c " STR, \
1261 (OSC), osc_is_ready(OSC), \
1262 list_empty_marker(&(OSC)->oo_hp_ready_item), \
1263 list_empty_marker(&(OSC)->oo_ready_item), \
1264 atomic_read(&(OSC)->oo_nr_writes), \
1265 list_empty_marker(&(OSC)->oo_hp_exts), \
1266 list_empty_marker(&(OSC)->oo_urgent_exts), \
1267 atomic_read(&(OSC)->oo_nr_reads), \
1268 list_empty_marker(&(OSC)->oo_reading_exts), \
1271 static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
1274 struct osc_page *opg = oap2osc_page(oap);
1275 struct cl_page *page = oap2cl_page(oap);
1278 LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
1281 result = cl_page_make_ready(env, page, CRT_WRITE);
1283 opg->ops_submit_time = cfs_time_current();
1287 static int osc_refresh_count(const struct lu_env *env,
1288 struct osc_async_page *oap, int cmd)
1290 struct osc_page *opg = oap2osc_page(oap);
1291 pgoff_t index = osc_index(oap2osc(oap));
1292 struct cl_object *obj;
1293 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
1298 /* readpage queues with _COUNT_STABLE, shouldn't get here. */
1299 LASSERT(!(cmd & OBD_BRW_READ));
1300 LASSERT(opg != NULL);
1301 obj = opg->ops_cl.cpl_obj;
1303 cl_object_attr_lock(obj);
1304 result = cl_object_attr_get(env, obj, attr);
1305 cl_object_attr_unlock(obj);
1308 kms = attr->cat_kms;
1309 if (cl_offset(obj, index) >= kms)
1310 /* catch race with truncate */
1312 else if (cl_offset(obj, index + 1) > kms)
1313 /* catch sub-page write at end of file */
1314 return kms % PAGE_SIZE;
1319 static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
1322 struct osc_page *opg = oap2osc_page(oap);
1323 struct cl_page *page = oap2cl_page(oap);
1324 enum cl_req_type crt;
1329 cmd &= ~OBD_BRW_NOQUOTA;
1330 LASSERTF(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ),
1331 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1332 LASSERTF(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE),
1333 "cp_state:%u, cmd:%d\n", page->cp_state, cmd);
1334 LASSERT(opg->ops_transfer_pinned);
1336 crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
1337 /* Clear opg->ops_transfer_pinned before VM lock is released. */
1338 opg->ops_transfer_pinned = 0;
1340 opg->ops_submit_time = 0;
1341 srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
1344 if (rc == 0 && srvlock) {
1345 struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
1346 struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
1347 size_t bytes = oap->oap_count;
1349 if (crt == CRT_READ)
1350 stats->os_lockless_reads += bytes;
1352 stats->os_lockless_writes += bytes;
1356 * This has to be the last operation with the page, as locks are
1357 * released in cl_page_completion() and nothing except for the
1358 * reference counter protects page from concurrent reclaim.
1360 lu_ref_del(&page->cp_reference, "transfer", page);
1362 cl_page_completion(env, page, crt, rc);
1363 cl_page_put(env, page);
1368 #define OSC_DUMP_GRANT(lvl, cli, fmt, args...) do { \
1369 struct client_obd *__tmp = (cli); \
1370 CDEBUG(lvl, "%s: grant { dirty: %ld/%ld dirty_pages: %ld/%lu " \
1371 "dropped: %ld avail: %ld, dirty_grant: %ld, " \
1372 "reserved: %ld, flight: %d } lru {in list: %ld, " \
1373 "left: %ld, waiters: %d }" fmt "\n", \
1375 __tmp->cl_dirty_pages, __tmp->cl_dirty_max_pages, \
1376 atomic_long_read(&obd_dirty_pages), obd_max_dirty_pages, \
1377 __tmp->cl_lost_grant, __tmp->cl_avail_grant, \
1378 __tmp->cl_dirty_grant, \
1379 __tmp->cl_reserved_grant, __tmp->cl_w_in_flight, \
1380 atomic_long_read(&__tmp->cl_lru_in_list), \
1381 atomic_long_read(&__tmp->cl_lru_busy), \
1382 atomic_read(&__tmp->cl_lru_shrinkers), ##args); \
1385 /* caller must hold loi_list_lock */
1386 static void osc_consume_write_grant(struct client_obd *cli,
1387 struct brw_page *pga)
1389 assert_spin_locked(&cli->cl_loi_list_lock);
1390 LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
1391 atomic_long_inc(&obd_dirty_pages);
1392 cli->cl_dirty_pages++;
1393 pga->flag |= OBD_BRW_FROM_GRANT;
1394 CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
1395 PAGE_SIZE, pga, pga->pg);
1396 osc_update_next_shrink(cli);
1399 /* the companion to osc_consume_write_grant, called when a brw has completed.
1400 * must be called with the loi lock held. */
1401 static void osc_release_write_grant(struct client_obd *cli,
1402 struct brw_page *pga)
1406 assert_spin_locked(&cli->cl_loi_list_lock);
1407 if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
1412 pga->flag &= ~OBD_BRW_FROM_GRANT;
1413 atomic_long_dec(&obd_dirty_pages);
1414 cli->cl_dirty_pages--;
1415 if (pga->flag & OBD_BRW_NOCACHE) {
1416 pga->flag &= ~OBD_BRW_NOCACHE;
1417 atomic_long_dec(&obd_dirty_transit_pages);
1418 cli->cl_dirty_transit--;
1424 * To avoid sleeping with object lock held, it's good for us allocate enough
1425 * grants before entering into critical section.
1427 * client_obd_list_lock held by caller
1429 static int osc_reserve_grant(struct client_obd *cli, unsigned int bytes)
1433 if (cli->cl_avail_grant >= bytes) {
1434 cli->cl_avail_grant -= bytes;
1435 cli->cl_reserved_grant += bytes;
1441 static void __osc_unreserve_grant(struct client_obd *cli,
1442 unsigned int reserved, unsigned int unused)
1444 /* it's quite normal for us to get more grant than reserved.
1445 * Thinking about a case that two extents merged by adding a new
1446 * chunk, we can save one extent tax. If extent tax is greater than
1447 * one chunk, we can save more grant by adding a new chunk */
1448 cli->cl_reserved_grant -= reserved;
1449 if (unused > reserved) {
1450 cli->cl_avail_grant += reserved;
1451 cli->cl_lost_grant += unused - reserved;
1452 cli->cl_dirty_grant -= unused - reserved;
1454 cli->cl_avail_grant += unused;
1455 cli->cl_dirty_grant += reserved - unused;
1459 static void osc_unreserve_grant(struct client_obd *cli,
1460 unsigned int reserved, unsigned int unused)
1462 spin_lock(&cli->cl_loi_list_lock);
1463 __osc_unreserve_grant(cli, reserved, unused);
1465 osc_wake_cache_waiters(cli);
1466 spin_unlock(&cli->cl_loi_list_lock);
1470 * Free grant after IO is finished or canceled.
1472 * @lost_grant is used to remember how many grants we have allocated but not
1473 * used, we should return these grants to OST. There're two cases where grants
1476 * 2. blocksize at OST is less than PAGE_SIZE and a partial page was
1477 * written. In this case OST may use less chunks to serve this partial
1478 * write. OSTs don't actually know the page size on the client side. so
1479 * clients have to calculate lost grant by the blocksize on the OST.
1480 * See filter_grant_check() for details.
1482 static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
1483 unsigned int lost_grant, unsigned int dirty_grant)
1485 unsigned long grant;
1487 grant = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
1489 spin_lock(&cli->cl_loi_list_lock);
1490 atomic_long_sub(nr_pages, &obd_dirty_pages);
1491 cli->cl_dirty_pages -= nr_pages;
1492 cli->cl_lost_grant += lost_grant;
1493 cli->cl_dirty_grant -= dirty_grant;
1494 if (cli->cl_avail_grant < grant && cli->cl_lost_grant >= grant) {
1495 /* borrow some grant from truncate to avoid the case that
1496 * truncate uses up all avail grant */
1497 cli->cl_lost_grant -= grant;
1498 cli->cl_avail_grant += grant;
1500 osc_wake_cache_waiters(cli);
1501 spin_unlock(&cli->cl_loi_list_lock);
1502 CDEBUG(D_CACHE, "lost %u grant: %lu avail: %lu dirty: %lu/%lu\n",
1503 lost_grant, cli->cl_lost_grant,
1504 cli->cl_avail_grant, cli->cl_dirty_pages << PAGE_SHIFT,
1505 cli->cl_dirty_grant);
1509 * The companion to osc_enter_cache(), called when @oap is no longer part of
1510 * the dirty accounting due to error.
1512 static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap)
1514 spin_lock(&cli->cl_loi_list_lock);
1515 osc_release_write_grant(cli, &oap->oap_brw_page);
1516 spin_unlock(&cli->cl_loi_list_lock);
1520 * Non-blocking version of osc_enter_cache() that consumes grant only when it
1523 static int osc_enter_cache_try(struct client_obd *cli,
1524 struct osc_async_page *oap,
1525 int bytes, int transient)
1529 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1531 rc = osc_reserve_grant(cli, bytes);
1535 if (cli->cl_dirty_pages < cli->cl_dirty_max_pages &&
1536 1 + atomic_long_read(&obd_dirty_pages) <= obd_max_dirty_pages) {
1537 osc_consume_write_grant(cli, &oap->oap_brw_page);
1539 cli->cl_dirty_transit++;
1540 atomic_long_inc(&obd_dirty_transit_pages);
1541 oap->oap_brw_flags |= OBD_BRW_NOCACHE;
1545 __osc_unreserve_grant(cli, bytes, bytes);
1551 static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
1554 spin_lock(&cli->cl_loi_list_lock);
1555 rc = list_empty(&ocw->ocw_entry);
1556 spin_unlock(&cli->cl_loi_list_lock);
1561 * The main entry to reserve dirty page accounting. Usually the grant reserved
1562 * in this function will be freed in bulk in osc_free_grant() unless it fails
1563 * to add osc cache, in that case, it will be freed in osc_exit_cache().
1565 * The process will be put into sleep if it's already run out of grant.
1567 static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
1568 struct osc_async_page *oap, int bytes)
1570 struct osc_object *osc = oap->oap_obj;
1571 struct lov_oinfo *loi = osc->oo_oinfo;
1572 struct osc_cache_waiter ocw;
1573 struct l_wait_info lwi;
1577 lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(AT_OFF ? obd_timeout : at_max),
1578 NULL, LWI_ON_SIGNAL_NOOP, NULL);
1580 OSC_DUMP_GRANT(D_CACHE, cli, "need:%d\n", bytes);
1582 spin_lock(&cli->cl_loi_list_lock);
1584 /* force the caller to try sync io. this can jump the list
1585 * of queued writes and create a discontiguous rpc stream */
1586 if (OBD_FAIL_CHECK(OBD_FAIL_OSC_NO_GRANT) ||
1587 cli->cl_dirty_max_pages == 0 ||
1588 cli->cl_ar.ar_force_sync || loi->loi_ar.ar_force_sync) {
1589 OSC_DUMP_GRANT(D_CACHE, cli, "forced sync i/o\n");
1590 GOTO(out, rc = -EDQUOT);
1593 /* Hopefully normal case - cache space and write credits available */
1594 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1595 OSC_DUMP_GRANT(D_CACHE, cli, "granted from cache\n");
1599 /* We can get here for two reasons: too many dirty pages in cache, or
1600 * run out of grants. In both cases we should write dirty pages out.
1601 * Adding a cache waiter will trigger urgent write-out no matter what
1603 * The exiting condition is no avail grants and no dirty pages caching,
1604 * that really means there is no space on the OST. */
1605 init_waitqueue_head(&ocw.ocw_waitq);
1607 ocw.ocw_grant = bytes;
1608 while (cli->cl_dirty_pages > 0 || cli->cl_w_in_flight > 0) {
1609 list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
1611 spin_unlock(&cli->cl_loi_list_lock);
1613 osc_io_unplug_async(env, cli, NULL);
1615 CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
1616 cli_name(cli), &ocw, oap);
1618 rc = l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
1620 spin_lock(&cli->cl_loi_list_lock);
1623 /* l_wait_event is interrupted by signal or timed out */
1624 list_del_init(&ocw.ocw_entry);
1627 LASSERT(list_empty(&ocw.ocw_entry));
1632 if (osc_enter_cache_try(cli, oap, bytes, 0)) {
1640 OSC_DUMP_GRANT(D_CACHE, cli, "finally got grant space\n");
1643 OSC_DUMP_GRANT(D_CACHE, cli,
1644 "timeout, fall back to sync i/o\n");
1645 osc_extent_tree_dump(D_CACHE, osc);
1646 /* fall back to synchronous I/O */
1650 /* Ensures restartability - LU-3581 */
1651 OSC_DUMP_GRANT(D_CACHE, cli, "interrupted\n");
1655 OSC_DUMP_GRANT(D_CACHE, cli,
1656 "no grant space, fall back to sync i/o\n");
1659 CDEBUG(D_CACHE, "%s: event for cache space @ %p never arrived "
1660 "due to %d, fall back to sync i/o\n",
1661 cli_name(cli), &ocw, rc);
1666 spin_unlock(&cli->cl_loi_list_lock);
1670 /* caller must hold loi_list_lock */
1671 void osc_wake_cache_waiters(struct client_obd *cli)
1673 struct list_head *l, *tmp;
1674 struct osc_cache_waiter *ocw;
1677 list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
1678 ocw = list_entry(l, struct osc_cache_waiter, ocw_entry);
1679 list_del_init(&ocw->ocw_entry);
1681 ocw->ocw_rc = -EDQUOT;
1682 /* we can't dirty more */
1683 if ((cli->cl_dirty_pages >= cli->cl_dirty_max_pages) ||
1684 (1 + atomic_long_read(&obd_dirty_pages) >
1685 obd_max_dirty_pages)) {
1686 CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
1687 "osc max %ld, sys max %ld\n",
1688 cli->cl_dirty_pages, cli->cl_dirty_max_pages,
1689 obd_max_dirty_pages);
1693 if (osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
1696 CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
1697 ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
1699 wake_up(&ocw->ocw_waitq);
1705 static int osc_max_rpc_in_flight(struct client_obd *cli, struct osc_object *osc)
1707 int hprpc = !!list_empty(&osc->oo_hp_exts);
1708 return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
1711 /* This maintains the lists of pending pages to read/write for a given object
1712 * (lop). This is used by osc_check_rpcs->osc_next_obj() and osc_list_maint()
1713 * to quickly find objects that are ready to send an RPC. */
1714 static int osc_makes_rpc(struct client_obd *cli, struct osc_object *osc,
1717 int invalid_import = 0;
1720 /* if we have an invalid import we want to drain the queued pages
1721 * by forcing them through rpcs that immediately fail and complete
1722 * the pages. recovery relies on this to empty the queued pages
1723 * before canceling the locks and evicting down the llite pages */
1724 if ((cli->cl_import == NULL || cli->cl_import->imp_invalid))
1727 if (cmd & OBD_BRW_WRITE) {
1728 if (atomic_read(&osc->oo_nr_writes) == 0)
1730 if (invalid_import) {
1731 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1734 if (!list_empty(&osc->oo_hp_exts)) {
1735 CDEBUG(D_CACHE, "high prio request forcing RPC\n");
1738 if (!list_empty(&osc->oo_urgent_exts)) {
1739 CDEBUG(D_CACHE, "urgent request forcing RPC\n");
1742 /* trigger a write rpc stream as long as there are dirtiers
1743 * waiting for space. as they're waiting, they're not going to
1744 * create more pages to coalesce with what's waiting.. */
1745 if (!list_empty(&cli->cl_cache_waiters)) {
1746 CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
1749 if (!list_empty(&osc->oo_full_exts)) {
1750 CDEBUG(D_CACHE, "full extent ready, make an RPC\n");
1754 if (atomic_read(&osc->oo_nr_reads) == 0)
1756 if (invalid_import) {
1757 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1760 /* all read are urgent. */
1761 if (!list_empty(&osc->oo_reading_exts))
1768 static void osc_update_pending(struct osc_object *obj, int cmd, int delta)
1770 struct client_obd *cli = osc_cli(obj);
1771 if (cmd & OBD_BRW_WRITE) {
1772 atomic_add(delta, &obj->oo_nr_writes);
1773 atomic_add(delta, &cli->cl_pending_w_pages);
1774 LASSERT(atomic_read(&obj->oo_nr_writes) >= 0);
1776 atomic_add(delta, &obj->oo_nr_reads);
1777 atomic_add(delta, &cli->cl_pending_r_pages);
1778 LASSERT(atomic_read(&obj->oo_nr_reads) >= 0);
1780 OSC_IO_DEBUG(obj, "update pending cmd %d delta %d.\n", cmd, delta);
1783 static int osc_makes_hprpc(struct osc_object *obj)
1785 return !list_empty(&obj->oo_hp_exts);
1788 static void on_list(struct list_head *item, struct list_head *list,
1791 if (list_empty(item) && should_be_on)
1792 list_add_tail(item, list);
1793 else if (!list_empty(item) && !should_be_on)
1794 list_del_init(item);
1797 /* maintain the osc's cli list membership invariants so that osc_send_oap_rpc
1798 * can find pages to build into rpcs quickly */
1799 static int __osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1801 if (osc_makes_hprpc(osc)) {
1803 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list, 0);
1804 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
1806 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
1807 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list,
1808 osc_makes_rpc(cli, osc, OBD_BRW_WRITE) ||
1809 osc_makes_rpc(cli, osc, OBD_BRW_READ));
1812 on_list(&osc->oo_write_item, &cli->cl_loi_write_list,
1813 atomic_read(&osc->oo_nr_writes) > 0);
1815 on_list(&osc->oo_read_item, &cli->cl_loi_read_list,
1816 atomic_read(&osc->oo_nr_reads) > 0);
1818 return osc_is_ready(osc);
1821 static int osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1825 spin_lock(&cli->cl_loi_list_lock);
1826 is_ready = __osc_list_maint(cli, osc);
1827 spin_unlock(&cli->cl_loi_list_lock);
1832 /* this is trying to propogate async writeback errors back up to the
1833 * application. As an async write fails we record the error code for later if
1834 * the app does an fsync. As long as errors persist we force future rpcs to be
1835 * sync so that the app can get a sync error and break the cycle of queueing
1836 * pages for which writeback will fail. */
1837 static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
1844 ar->ar_force_sync = 1;
1845 ar->ar_min_xid = ptlrpc_sample_next_xid();
1850 if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
1851 ar->ar_force_sync = 0;
1854 /* this must be called holding the loi list lock to give coverage to exit_cache,
1855 * async_flag maintenance, and oap_request */
1856 static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
1857 struct osc_async_page *oap, int sent, int rc)
1859 struct osc_object *osc = oap->oap_obj;
1860 struct lov_oinfo *loi = osc->oo_oinfo;
1864 if (oap->oap_request != NULL) {
1865 xid = ptlrpc_req_xid(oap->oap_request);
1866 ptlrpc_req_finished(oap->oap_request);
1867 oap->oap_request = NULL;
1870 /* As the transfer for this page is being done, clear the flags */
1871 spin_lock(&oap->oap_lock);
1872 oap->oap_async_flags = 0;
1873 spin_unlock(&oap->oap_lock);
1874 oap->oap_interrupted = 0;
1876 if (oap->oap_cmd & OBD_BRW_WRITE && xid > 0) {
1877 spin_lock(&cli->cl_loi_list_lock);
1878 osc_process_ar(&cli->cl_ar, xid, rc);
1879 osc_process_ar(&loi->loi_ar, xid, rc);
1880 spin_unlock(&cli->cl_loi_list_lock);
1883 rc = osc_completion(env, oap, oap->oap_cmd, rc);
1885 CERROR("completion on oap %p obj %p returns %d.\n",
1891 struct extent_rpc_data {
1892 struct list_head *erd_rpc_list;
1893 unsigned int erd_page_count;
1894 unsigned int erd_max_pages;
1895 unsigned int erd_max_chunks;
1896 unsigned int erd_max_extents;
1899 static inline unsigned osc_extent_chunks(const struct osc_extent *ext)
1901 struct client_obd *cli = osc_cli(ext->oe_obj);
1902 unsigned ppc_bits = cli->cl_chunkbits - PAGE_SHIFT;
1904 return (ext->oe_end >> ppc_bits) - (ext->oe_start >> ppc_bits) + 1;
1908 * Try to add extent to one RPC. We need to think about the following things:
1909 * - # of pages must not be over max_pages_per_rpc
1910 * - extent must be compatible with previous ones
1912 static int try_to_add_extent_for_io(struct client_obd *cli,
1913 struct osc_extent *ext,
1914 struct extent_rpc_data *data)
1916 struct osc_extent *tmp;
1917 unsigned int chunk_count;
1918 struct osc_async_page *oap = list_first_entry(&ext->oe_pages,
1919 struct osc_async_page,
1923 EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE),
1925 OSC_EXTENT_DUMP(D_CACHE, ext, "trying to add this extent\n");
1927 if (data->erd_max_extents == 0)
1930 chunk_count = osc_extent_chunks(ext);
1931 EASSERTF(data->erd_page_count != 0 ||
1932 chunk_count <= data->erd_max_chunks, ext,
1933 "The first extent to be fit in a RPC contains %u chunks, "
1934 "which is over the limit %u.\n", chunk_count,
1935 data->erd_max_chunks);
1936 if (chunk_count > data->erd_max_chunks)
1939 data->erd_max_pages = max(ext->oe_mppr, data->erd_max_pages);
1940 EASSERTF(data->erd_page_count != 0 ||
1941 ext->oe_nr_pages <= data->erd_max_pages, ext,
1942 "The first extent to be fit in a RPC contains %u pages, "
1943 "which is over the limit %u.\n", ext->oe_nr_pages,
1944 data->erd_max_pages);
1945 if (data->erd_page_count + ext->oe_nr_pages > data->erd_max_pages)
1948 list_for_each_entry(tmp, data->erd_rpc_list, oe_link) {
1949 struct osc_async_page *oap2;
1950 oap2 = list_first_entry(&tmp->oe_pages, struct osc_async_page,
1952 EASSERT(tmp->oe_owner == current, tmp);
1954 if (overlapped(tmp, ext)) {
1955 OSC_EXTENT_DUMP(D_ERROR, tmp, "overlapped %p.\n", ext);
1959 if (oap2cl_page(oap)->cp_type != oap2cl_page(oap2)->cp_type) {
1960 CDEBUG(D_CACHE, "Do not permit different types of IO "
1965 if (tmp->oe_srvlock != ext->oe_srvlock ||
1966 !tmp->oe_grants != !ext->oe_grants ||
1967 tmp->oe_no_merge || ext->oe_no_merge)
1970 /* remove break for strict check */
1974 data->erd_max_extents--;
1975 data->erd_max_chunks -= chunk_count;
1976 data->erd_page_count += ext->oe_nr_pages;
1977 list_move_tail(&ext->oe_link, data->erd_rpc_list);
1978 ext->oe_owner = current;
1982 static inline unsigned osc_max_write_chunks(const struct client_obd *cli)
1987 * The maximum size of a single transaction is about 64MB in ZFS.
1988 * #define DMU_MAX_ACCESS (64 * 1024 * 1024)
1990 * Since ZFS is a copy-on-write file system, a single dirty page in
1991 * a chunk will result in the rewrite of the whole chunk, therefore
1992 * an RPC shouldn't be allowed to contain too many chunks otherwise
1993 * it will make transaction size much bigger than 64MB, especially
1994 * with big block size for ZFS.
1996 * This piece of code is to make sure that OSC won't send write RPCs
1997 * with too many chunks. The maximum chunk size that an RPC can cover
1998 * is set to PTLRPC_MAX_BRW_SIZE, which is defined to 16MB. Ideally
1999 * OST should tell the client what the biggest transaction size is,
2000 * but it's good enough for now.
2002 * This limitation doesn't apply to ldiskfs, which allows as many
2003 * chunks in one RPC as we want. However, it won't have any benefits
2004 * to have too many discontiguous pages in one RPC.
2006 * An osc_extent won't cover over a RPC size, so the chunks in an
2007 * osc_extent won't bigger than PTLRPC_MAX_BRW_SIZE >> chunkbits.
2009 return PTLRPC_MAX_BRW_SIZE >> cli->cl_chunkbits;
2013 * In order to prevent multiple ptlrpcd from breaking contiguous extents,
2014 * get_write_extent() takes all appropriate extents in atomic.
2016 * The following policy is used to collect extents for IO:
2017 * 1. Add as many HP extents as possible;
2018 * 2. Add the first urgent extent in urgent extent list and take it out of
2020 * 3. Add subsequent extents of this urgent extent;
2021 * 4. If urgent list is not empty, goto 2;
2022 * 5. Traverse the extent tree from the 1st extent;
2023 * 6. Above steps exit if there is no space in this RPC.
2025 static unsigned int get_write_extents(struct osc_object *obj,
2026 struct list_head *rpclist)
2028 struct client_obd *cli = osc_cli(obj);
2029 struct osc_extent *ext;
2030 struct extent_rpc_data data = {
2031 .erd_rpc_list = rpclist,
2032 .erd_page_count = 0,
2033 .erd_max_pages = cli->cl_max_pages_per_rpc,
2034 .erd_max_chunks = osc_max_write_chunks(cli),
2035 .erd_max_extents = 256,
2038 LASSERT(osc_object_is_locked(obj));
2039 while (!list_empty(&obj->oo_hp_exts)) {
2040 ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
2042 LASSERT(ext->oe_state == OES_CACHE);
2043 if (!try_to_add_extent_for_io(cli, ext, &data))
2044 return data.erd_page_count;
2045 EASSERT(ext->oe_nr_pages <= data.erd_max_pages, ext);
2047 if (data.erd_page_count == data.erd_max_pages)
2048 return data.erd_page_count;
2050 while (!list_empty(&obj->oo_urgent_exts)) {
2051 ext = list_entry(obj->oo_urgent_exts.next,
2052 struct osc_extent, oe_link);
2053 if (!try_to_add_extent_for_io(cli, ext, &data))
2054 return data.erd_page_count;
2056 if (data.erd_page_count == data.erd_max_pages)
2057 return data.erd_page_count;
2059 /* One key difference between full extents and other extents: full
2060 * extents can usually only be added if the rpclist was empty, so if we
2061 * can't add one, we continue on to trying to add normal extents. This
2062 * is so we don't miss adding extra extents to an RPC containing high
2063 * priority or urgent extents. */
2064 while (!list_empty(&obj->oo_full_exts)) {
2065 ext = list_entry(obj->oo_full_exts.next,
2066 struct osc_extent, oe_link);
2067 if (!try_to_add_extent_for_io(cli, ext, &data))
2070 if (data.erd_page_count == data.erd_max_pages)
2071 return data.erd_page_count;
2073 ext = first_extent(obj);
2074 while (ext != NULL) {
2075 if ((ext->oe_state != OES_CACHE) ||
2076 /* this extent may be already in current rpclist */
2077 (!list_empty(&ext->oe_link) && ext->oe_owner != NULL)) {
2078 ext = next_extent(ext);
2082 if (!try_to_add_extent_for_io(cli, ext, &data))
2083 return data.erd_page_count;
2085 ext = next_extent(ext);
2087 return data.erd_page_count;
2091 osc_send_write_rpc(const struct lu_env *env, struct client_obd *cli,
2092 struct osc_object *osc)
2095 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2096 struct osc_extent *ext;
2097 struct osc_extent *tmp;
2098 struct osc_extent *first = NULL;
2099 unsigned int page_count = 0;
2104 LASSERT(osc_object_is_locked(osc));
2106 page_count = get_write_extents(osc, &rpclist);
2107 LASSERT(equi(page_count == 0, list_empty(&rpclist)));
2109 if (list_empty(&rpclist))
2112 osc_update_pending(osc, OBD_BRW_WRITE, -page_count);
2114 list_for_each_entry(ext, &rpclist, oe_link) {
2115 LASSERT(ext->oe_state == OES_CACHE ||
2116 ext->oe_state == OES_LOCK_DONE);
2117 if (ext->oe_state == OES_CACHE)
2118 osc_extent_state_set(ext, OES_LOCKING);
2120 osc_extent_state_set(ext, OES_RPC);
2123 /* we're going to grab page lock, so release object lock because
2124 * lock order is page lock -> object lock. */
2125 osc_object_unlock(osc);
2127 list_for_each_entry_safe(ext, tmp, &rpclist, oe_link) {
2128 if (ext->oe_state == OES_LOCKING) {
2129 rc = osc_extent_make_ready(env, ext);
2130 if (unlikely(rc < 0)) {
2131 list_del_init(&ext->oe_link);
2132 osc_extent_finish(env, ext, 0, rc);
2136 if (first == NULL) {
2138 srvlock = ext->oe_srvlock;
2140 LASSERT(srvlock == ext->oe_srvlock);
2144 if (!list_empty(&rpclist)) {
2145 LASSERT(page_count > 0);
2146 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_WRITE);
2147 LASSERT(list_empty(&rpclist));
2150 osc_object_lock(osc);
2155 * prepare pages for ASYNC io and put pages in send queue.
2157 * \param cmd OBD_BRW_* macroses
2158 * \param lop pending pages
2160 * \return zero if no page added to send queue.
2161 * \return 1 if pages successfully added to send queue.
2162 * \return negative on errors.
2165 osc_send_read_rpc(const struct lu_env *env, struct client_obd *cli,
2166 struct osc_object *osc)
2169 struct osc_extent *ext;
2170 struct osc_extent *next;
2171 struct list_head rpclist = LIST_HEAD_INIT(rpclist);
2172 struct extent_rpc_data data = {
2173 .erd_rpc_list = &rpclist,
2174 .erd_page_count = 0,
2175 .erd_max_pages = cli->cl_max_pages_per_rpc,
2176 .erd_max_chunks = UINT_MAX,
2177 .erd_max_extents = UINT_MAX,
2182 LASSERT(osc_object_is_locked(osc));
2183 list_for_each_entry_safe(ext, next, &osc->oo_reading_exts, oe_link) {
2184 EASSERT(ext->oe_state == OES_LOCK_DONE, ext);
2185 if (!try_to_add_extent_for_io(cli, ext, &data))
2187 osc_extent_state_set(ext, OES_RPC);
2188 EASSERT(ext->oe_nr_pages <= data.erd_max_pages, ext);
2190 LASSERT(data.erd_page_count <= data.erd_max_pages);
2192 osc_update_pending(osc, OBD_BRW_READ, -data.erd_page_count);
2194 if (!list_empty(&rpclist)) {
2195 osc_object_unlock(osc);
2197 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_READ);
2198 LASSERT(list_empty(&rpclist));
2200 osc_object_lock(osc);
2205 #define list_to_obj(list, item) ({ \
2206 struct list_head *__tmp = (list)->next; \
2207 list_del_init(__tmp); \
2208 list_entry(__tmp, struct osc_object, oo_##item); \
2211 /* This is called by osc_check_rpcs() to find which objects have pages that
2212 * we could be sending. These lists are maintained by osc_makes_rpc(). */
2213 static struct osc_object *osc_next_obj(struct client_obd *cli)
2217 /* First return objects that have blocked locks so that they
2218 * will be flushed quickly and other clients can get the lock,
2219 * then objects which have pages ready to be stuffed into RPCs */
2220 if (!list_empty(&cli->cl_loi_hp_ready_list))
2221 RETURN(list_to_obj(&cli->cl_loi_hp_ready_list, hp_ready_item));
2222 if (!list_empty(&cli->cl_loi_ready_list))
2223 RETURN(list_to_obj(&cli->cl_loi_ready_list, ready_item));
2225 /* then if we have cache waiters, return all objects with queued
2226 * writes. This is especially important when many small files
2227 * have filled up the cache and not been fired into rpcs because
2228 * they don't pass the nr_pending/object threshhold */
2229 if (!list_empty(&cli->cl_cache_waiters) &&
2230 !list_empty(&cli->cl_loi_write_list))
2231 RETURN(list_to_obj(&cli->cl_loi_write_list, write_item));
2233 /* then return all queued objects when we have an invalid import
2234 * so that they get flushed */
2235 if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
2236 if (!list_empty(&cli->cl_loi_write_list))
2237 RETURN(list_to_obj(&cli->cl_loi_write_list,
2239 if (!list_empty(&cli->cl_loi_read_list))
2240 RETURN(list_to_obj(&cli->cl_loi_read_list,
2246 /* called with the loi list lock held */
2247 static void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli)
2248 __must_hold(&cli->cl_loi_list_lock)
2250 struct osc_object *osc;
2254 while ((osc = osc_next_obj(cli)) != NULL) {
2255 struct cl_object *obj = osc2cl(osc);
2256 struct lu_ref_link link;
2258 OSC_IO_DEBUG(osc, "%lu in flight\n", rpcs_in_flight(cli));
2260 if (osc_max_rpc_in_flight(cli, osc)) {
2261 __osc_list_maint(cli, osc);
2266 spin_unlock(&cli->cl_loi_list_lock);
2267 lu_object_ref_add_at(&obj->co_lu, &link, "check", current);
2269 /* attempt some read/write balancing by alternating between
2270 * reads and writes in an object. The makes_rpc checks here
2271 * would be redundant if we were getting read/write work items
2272 * instead of objects. we don't want send_oap_rpc to drain a
2273 * partial read pending queue when we're given this object to
2274 * do io on writes while there are cache waiters */
2275 osc_object_lock(osc);
2276 if (osc_makes_rpc(cli, osc, OBD_BRW_WRITE)) {
2277 rc = osc_send_write_rpc(env, cli, osc);
2279 CERROR("Write request failed with %d\n", rc);
2281 /* osc_send_write_rpc failed, mostly because of
2284 * It can't break here, because if:
2285 * - a page was submitted by osc_io_submit, so
2287 * - no request in flight
2288 * - no subsequent request
2289 * The system will be in live-lock state,
2290 * because there is no chance to call
2291 * osc_io_unplug() and osc_check_rpcs() any
2292 * more. pdflush can't help in this case,
2293 * because it might be blocked at grabbing
2294 * the page lock as we mentioned.
2296 * Anyway, continue to drain pages. */
2300 if (osc_makes_rpc(cli, osc, OBD_BRW_READ)) {
2301 rc = osc_send_read_rpc(env, cli, osc);
2303 CERROR("Read request failed with %d\n", rc);
2305 osc_object_unlock(osc);
2307 osc_list_maint(cli, osc);
2308 lu_object_ref_del_at(&obj->co_lu, &link, "check", current);
2309 cl_object_put(env, obj);
2311 spin_lock(&cli->cl_loi_list_lock);
2315 static int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
2316 struct osc_object *osc, int async)
2320 if (osc != NULL && osc_list_maint(cli, osc) == 0)
2324 spin_lock(&cli->cl_loi_list_lock);
2325 osc_check_rpcs(env, cli);
2326 spin_unlock(&cli->cl_loi_list_lock);
2328 CDEBUG(D_CACHE, "Queue writeback work for client %p.\n", cli);
2329 LASSERT(cli->cl_writeback_work != NULL);
2330 rc = ptlrpcd_queue_work(cli->cl_writeback_work);
2335 static int osc_io_unplug_async(const struct lu_env *env,
2336 struct client_obd *cli, struct osc_object *osc)
2338 return osc_io_unplug0(env, cli, osc, 1);
2341 void osc_io_unplug(const struct lu_env *env, struct client_obd *cli,
2342 struct osc_object *osc)
2344 (void)osc_io_unplug0(env, cli, osc, 0);
2347 int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
2348 struct page *page, loff_t offset)
2350 struct obd_export *exp = osc_export(osc);
2351 struct osc_async_page *oap = &ops->ops_oap;
2355 return cfs_size_round(sizeof(*oap));
2357 oap->oap_magic = OAP_MAGIC;
2358 oap->oap_cli = &exp->exp_obd->u.cli;
2361 oap->oap_page = page;
2362 oap->oap_obj_off = offset;
2363 LASSERT(!(offset & ~PAGE_MASK));
2365 if (cfs_capable(CFS_CAP_SYS_RESOURCE))
2366 oap->oap_brw_flags = OBD_BRW_NOQUOTA;
2368 INIT_LIST_HEAD(&oap->oap_pending_item);
2369 INIT_LIST_HEAD(&oap->oap_rpc_item);
2371 spin_lock_init(&oap->oap_lock);
2372 CDEBUG(D_INFO, "oap %p page %p obj off %llu\n",
2373 oap, page, oap->oap_obj_off);
2377 int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
2378 struct osc_page *ops)
2380 struct osc_io *oio = osc_env_io(env);
2381 struct osc_extent *ext = NULL;
2382 struct osc_async_page *oap = &ops->ops_oap;
2383 struct client_obd *cli = oap->oap_cli;
2384 struct osc_object *osc = oap->oap_obj;
2387 unsigned int grants = 0;
2388 u32 brw_flags = OBD_BRW_ASYNC;
2389 int cmd = OBD_BRW_WRITE;
2390 int need_release = 0;
2394 if (oap->oap_magic != OAP_MAGIC)
2397 if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
2400 if (!list_empty(&oap->oap_pending_item) ||
2401 !list_empty(&oap->oap_rpc_item))
2404 /* Set the OBD_BRW_SRVLOCK before the page is queued. */
2405 brw_flags |= ops->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
2406 if (cfs_capable(CFS_CAP_SYS_RESOURCE)) {
2407 brw_flags |= OBD_BRW_NOQUOTA;
2408 cmd |= OBD_BRW_NOQUOTA;
2411 /* check if the file's owner/group is over quota */
2412 if (!(cmd & OBD_BRW_NOQUOTA)) {
2413 struct cl_object *obj;
2414 struct cl_attr *attr;
2415 unsigned int qid[LL_MAXQUOTAS];
2417 obj = cl_object_top(&osc->oo_cl);
2418 attr = &osc_env_info(env)->oti_attr;
2420 cl_object_attr_lock(obj);
2421 rc = cl_object_attr_get(env, obj, attr);
2422 cl_object_attr_unlock(obj);
2424 qid[USRQUOTA] = attr->cat_uid;
2425 qid[GRPQUOTA] = attr->cat_gid;
2426 qid[PRJQUOTA] = attr->cat_projid;
2427 if (rc == 0 && osc_quota_chkdq(cli, qid) == NO_QUOTA)
2434 oap->oap_page_off = ops->ops_from;
2435 oap->oap_count = ops->ops_to - ops->ops_from;
2436 /* No need to hold a lock here,
2437 * since this page is not in any list yet. */
2438 oap->oap_async_flags = 0;
2439 oap->oap_brw_flags = brw_flags;
2441 OSC_IO_DEBUG(osc, "oap %p page %p added for cmd %d\n",
2442 oap, oap->oap_page, oap->oap_cmd & OBD_BRW_RWMASK);
2444 index = osc_index(oap2osc(oap));
2446 /* Add this page into extent by the following steps:
2447 * 1. if there exists an active extent for this IO, mostly this page
2448 * can be added to the active extent and sometimes we need to
2449 * expand extent to accomodate this page;
2450 * 2. otherwise, a new extent will be allocated. */
2452 ext = oio->oi_active;
2453 if (ext != NULL && ext->oe_start <= index && ext->oe_max_end >= index) {
2454 /* one chunk plus extent overhead must be enough to write this
2456 grants = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
2457 if (ext->oe_end >= index)
2460 /* it doesn't need any grant to dirty this page */
2461 spin_lock(&cli->cl_loi_list_lock);
2462 rc = osc_enter_cache_try(cli, oap, grants, 0);
2463 spin_unlock(&cli->cl_loi_list_lock);
2464 if (rc == 0) { /* try failed */
2467 } else if (ext->oe_end < index) {
2469 /* try to expand this extent */
2470 rc = osc_extent_expand(ext, index, &tmp);
2473 /* don't free reserved grant */
2475 OSC_EXTENT_DUMP(D_CACHE, ext,
2476 "expanded for %lu.\n", index);
2477 osc_unreserve_grant(cli, grants, tmp);
2482 } else if (ext != NULL) {
2483 /* index is located outside of active extent */
2487 osc_extent_release(env, ext);
2488 oio->oi_active = NULL;
2493 tmp = (1 << cli->cl_chunkbits) + cli->cl_grant_extent_tax;
2495 /* try to find new extent to cover this page */
2496 LASSERT(oio->oi_active == NULL);
2497 /* we may have allocated grant for this page if we failed
2498 * to expand the previous active extent. */
2499 LASSERT(ergo(grants > 0, grants >= tmp));
2503 /* we haven't allocated grant for this page. */
2504 rc = osc_enter_cache(env, cli, oap, tmp);
2511 ext = osc_extent_find(env, osc, index, &tmp);
2513 LASSERT(tmp == grants);
2514 osc_exit_cache(cli, oap);
2518 oio->oi_active = ext;
2522 osc_unreserve_grant(cli, grants, tmp);
2525 LASSERT(ergo(rc == 0, ext != NULL));
2527 EASSERTF(ext->oe_end >= index && ext->oe_start <= index,
2528 ext, "index = %lu.\n", index);
2529 LASSERT((oap->oap_brw_flags & OBD_BRW_FROM_GRANT) != 0);
2531 osc_object_lock(osc);
2532 if (ext->oe_nr_pages == 0)
2533 ext->oe_srvlock = ops->ops_srvlock;
2535 LASSERT(ext->oe_srvlock == ops->ops_srvlock);
2537 list_add_tail(&oap->oap_pending_item, &ext->oe_pages);
2538 osc_object_unlock(osc);
2543 int osc_teardown_async_page(const struct lu_env *env,
2544 struct osc_object *obj, struct osc_page *ops)
2546 struct osc_async_page *oap = &ops->ops_oap;
2550 LASSERT(oap->oap_magic == OAP_MAGIC);
2552 CDEBUG(D_INFO, "teardown oap %p page %p at index %lu.\n",
2553 oap, ops, osc_index(oap2osc(oap)));
2555 if (!list_empty(&oap->oap_rpc_item)) {
2556 CDEBUG(D_CACHE, "oap %p is not in cache.\n", oap);
2558 } else if (!list_empty(&oap->oap_pending_item)) {
2559 struct osc_extent *ext = NULL;
2561 osc_object_lock(obj);
2562 ext = osc_extent_lookup(obj, osc_index(oap2osc(oap)));
2563 osc_object_unlock(obj);
2564 /* only truncated pages are allowed to be taken out.
2565 * See osc_extent_truncate() and osc_cache_truncate_start()
2567 if (ext != NULL && ext->oe_state != OES_TRUNC) {
2568 OSC_EXTENT_DUMP(D_ERROR, ext, "trunc at %lu.\n",
2569 osc_index(oap2osc(oap)));
2573 osc_extent_put(env, ext);
2579 * This is called when a page is picked up by kernel to write out.
2581 * We should find out the corresponding extent and add the whole extent
2582 * into urgent list. The extent may be being truncated or used, handle it
2585 int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
2586 struct osc_page *ops)
2588 struct osc_extent *ext = NULL;
2589 struct osc_object *obj = cl2osc(ops->ops_cl.cpl_obj);
2590 struct cl_page *cp = ops->ops_cl.cpl_page;
2591 pgoff_t index = osc_index(ops);
2592 struct osc_async_page *oap = &ops->ops_oap;
2593 bool unplug = false;
2597 osc_object_lock(obj);
2598 ext = osc_extent_lookup(obj, index);
2600 osc_extent_tree_dump(D_ERROR, obj);
2601 LASSERTF(0, "page index %lu is NOT covered.\n", index);
2604 switch (ext->oe_state) {
2607 CL_PAGE_DEBUG(D_ERROR, env, cp, "flush an in-rpc page?\n");
2611 /* If we know this extent is being written out, we should abort
2612 * so that the writer can make this page ready. Otherwise, there
2613 * exists a deadlock problem because other process can wait for
2614 * page writeback bit holding page lock; and meanwhile in
2615 * vvp_page_make_ready(), we need to grab page lock before
2616 * really sending the RPC. */
2618 /* race with truncate, page will be redirtied */
2620 /* The extent is active so we need to abort and let the caller
2621 * re-dirty the page. If we continued on here, and we were the
2622 * one making the extent active, we could deadlock waiting for
2623 * the page writeback to clear but it won't because the extent
2624 * is active and won't be written out. */
2625 GOTO(out, rc = -EAGAIN);
2630 rc = cl_page_prep(env, io, cp, CRT_WRITE);
2634 spin_lock(&oap->oap_lock);
2635 oap->oap_async_flags |= ASYNC_READY|ASYNC_URGENT;
2636 spin_unlock(&oap->oap_lock);
2638 if (memory_pressure_get())
2639 ext->oe_memalloc = 1;
2642 if (ext->oe_state == OES_CACHE) {
2643 OSC_EXTENT_DUMP(D_CACHE, ext,
2644 "flush page %p make it urgent.\n", oap);
2645 if (list_empty(&ext->oe_link))
2646 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2653 osc_object_unlock(obj);
2654 osc_extent_put(env, ext);
2656 osc_io_unplug_async(env, osc_cli(obj), obj);
2661 * this is called when a sync waiter receives an interruption. Its job is to
2662 * get the caller woken as soon as possible. If its page hasn't been put in an
2663 * rpc yet it can dequeue immediately. Otherwise it has to mark the rpc as
2664 * desiring interruption which will forcefully complete the rpc once the rpc
2667 int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops)
2669 struct osc_async_page *oap = &ops->ops_oap;
2670 struct osc_object *obj = oap->oap_obj;
2671 struct client_obd *cli = osc_cli(obj);
2672 struct osc_extent *ext;
2673 struct osc_extent *found = NULL;
2674 struct list_head *plist;
2675 pgoff_t index = osc_index(ops);
2680 LASSERT(!oap->oap_interrupted);
2681 oap->oap_interrupted = 1;
2683 /* Find out the caching extent */
2684 osc_object_lock(obj);
2685 if (oap->oap_cmd & OBD_BRW_WRITE) {
2686 plist = &obj->oo_urgent_exts;
2687 cmd = OBD_BRW_WRITE;
2689 plist = &obj->oo_reading_exts;
2692 list_for_each_entry(ext, plist, oe_link) {
2693 if (ext->oe_start <= index && ext->oe_end >= index) {
2694 LASSERT(ext->oe_state == OES_LOCK_DONE);
2695 /* For OES_LOCK_DONE state extent, it has already held
2696 * a refcount for RPC. */
2697 found = osc_extent_get(ext);
2701 if (found != NULL) {
2702 list_del_init(&found->oe_link);
2703 osc_update_pending(obj, cmd, -found->oe_nr_pages);
2704 osc_object_unlock(obj);
2706 osc_extent_finish(env, found, 0, -EINTR);
2707 osc_extent_put(env, found);
2710 osc_object_unlock(obj);
2711 /* ok, it's been put in an rpc. only one oap gets a request
2713 if (oap->oap_request != NULL) {
2714 ptlrpc_mark_interrupted(oap->oap_request);
2715 ptlrpcd_wake(oap->oap_request);
2716 ptlrpc_req_finished(oap->oap_request);
2717 oap->oap_request = NULL;
2721 osc_list_maint(cli, obj);
2725 int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
2726 struct list_head *list, int cmd, int brw_flags)
2728 struct client_obd *cli = osc_cli(obj);
2729 struct osc_extent *ext;
2730 struct osc_async_page *oap;
2732 int mppr = cli->cl_max_pages_per_rpc;
2733 bool can_merge = true;
2734 pgoff_t start = CL_PAGE_EOF;
2738 list_for_each_entry(oap, list, oap_pending_item) {
2739 struct osc_page *opg = oap2osc_page(oap);
2740 pgoff_t index = osc_index(opg);
2747 mppr <<= (page_count > mppr);
2749 if (unlikely(opg->ops_from > 0 || opg->ops_to < PAGE_SIZE))
2753 ext = osc_extent_alloc(obj);
2755 struct osc_async_page *tmp;
2757 list_for_each_entry_safe(oap, tmp, list, oap_pending_item) {
2758 list_del_init(&oap->oap_pending_item);
2759 osc_ap_completion(env, cli, oap, 0, -ENOMEM);
2764 ext->oe_rw = !!(cmd & OBD_BRW_READ);
2766 ext->oe_no_merge = !can_merge;
2768 ext->oe_start = start;
2769 ext->oe_end = ext->oe_max_end = end;
2771 ext->oe_srvlock = !!(brw_flags & OBD_BRW_SRVLOCK);
2772 ext->oe_nr_pages = page_count;
2773 ext->oe_mppr = mppr;
2774 list_splice_init(list, &ext->oe_pages);
2776 osc_object_lock(obj);
2777 /* Reuse the initial refcount for RPC, don't drop it */
2778 osc_extent_state_set(ext, OES_LOCK_DONE);
2779 if (cmd & OBD_BRW_WRITE) {
2780 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2781 osc_update_pending(obj, OBD_BRW_WRITE, page_count);
2783 list_add_tail(&ext->oe_link, &obj->oo_reading_exts);
2784 osc_update_pending(obj, OBD_BRW_READ, page_count);
2786 osc_object_unlock(obj);
2788 osc_io_unplug_async(env, cli, obj);
2793 * Called by osc_io_setattr_start() to freeze and destroy covering extents.
2795 int osc_cache_truncate_start(const struct lu_env *env, struct osc_object *obj,
2796 __u64 size, struct osc_extent **extp)
2798 struct client_obd *cli = osc_cli(obj);
2799 struct osc_extent *ext;
2800 struct osc_extent *waiting = NULL;
2802 struct list_head list = LIST_HEAD_INIT(list);
2807 /* pages with index greater or equal to index will be truncated. */
2808 index = cl_index(osc2cl(obj), size);
2809 partial = size > cl_offset(osc2cl(obj), index);
2812 osc_object_lock(obj);
2813 ext = osc_extent_search(obj, index);
2815 ext = first_extent(obj);
2816 else if (ext->oe_end < index)
2817 ext = next_extent(ext);
2818 while (ext != NULL) {
2819 EASSERT(ext->oe_state != OES_TRUNC, ext);
2821 if (ext->oe_state > OES_CACHE || ext->oe_urgent) {
2822 /* if ext is in urgent state, it means there must exist
2823 * a page already having been flushed by write_page().
2824 * We have to wait for this extent because we can't
2825 * truncate that page. */
2826 OSC_EXTENT_DUMP(D_CACHE, ext,
2827 "waiting for busy extent\n");
2828 waiting = osc_extent_get(ext);
2832 OSC_EXTENT_DUMP(D_CACHE, ext, "try to trunc:%llu.\n", size);
2834 osc_extent_get(ext);
2835 if (ext->oe_state == OES_ACTIVE) {
2836 /* though we grab inode mutex for write path, but we
2837 * release it before releasing extent(in osc_io_end()),
2838 * so there is a race window that an extent is still
2839 * in OES_ACTIVE when truncate starts. */
2840 LASSERT(!ext->oe_trunc_pending);
2841 ext->oe_trunc_pending = 1;
2843 EASSERT(ext->oe_state == OES_CACHE, ext);
2844 osc_extent_state_set(ext, OES_TRUNC);
2845 osc_update_pending(obj, OBD_BRW_WRITE,
2848 /* This extent could be on the full extents list, that's OK */
2849 EASSERT(!ext->oe_hp && !ext->oe_urgent, ext);
2850 if (!list_empty(&ext->oe_link))
2851 list_move_tail(&ext->oe_link, &list);
2853 list_add_tail(&ext->oe_link, &list);
2855 ext = next_extent(ext);
2857 osc_object_unlock(obj);
2859 osc_list_maint(cli, obj);
2861 while (!list_empty(&list)) {
2864 ext = list_entry(list.next, struct osc_extent, oe_link);
2865 list_del_init(&ext->oe_link);
2867 /* extent may be in OES_ACTIVE state because inode mutex
2868 * is released before osc_io_end() in file write case */
2869 if (ext->oe_state != OES_TRUNC)
2870 osc_extent_wait(env, ext, OES_TRUNC);
2872 rc = osc_extent_truncate(ext, index, partial);
2877 OSC_EXTENT_DUMP(D_ERROR, ext,
2878 "truncate error %d\n", rc);
2879 } else if (ext->oe_nr_pages == 0) {
2880 osc_extent_remove(ext);
2882 /* this must be an overlapped extent which means only
2883 * part of pages in this extent have been truncated.
2885 EASSERTF(ext->oe_start <= index, ext,
2886 "trunc index = %lu/%d.\n", index, partial);
2887 /* fix index to skip this partially truncated extent */
2888 index = ext->oe_end + 1;
2891 /* we need to hold this extent in OES_TRUNC state so
2892 * that no writeback will happen. This is to avoid
2894 * Only partial truncate can reach here, if @size is
2895 * not zero, the caller should provide a valid @extp. */
2896 LASSERT(*extp == NULL);
2897 *extp = osc_extent_get(ext);
2898 OSC_EXTENT_DUMP(D_CACHE, ext,
2899 "trunc at %llu\n", size);
2901 osc_extent_put(env, ext);
2903 if (waiting != NULL) {
2906 /* ignore the result of osc_extent_wait the write initiator
2907 * should take care of it. */
2908 rc = osc_extent_wait(env, waiting, OES_INV);
2910 OSC_EXTENT_DUMP(D_CACHE, waiting, "error: %d.\n", rc);
2912 osc_extent_put(env, waiting);
2920 * Called after osc_io_setattr_end to add oio->oi_trunc back to cache.
2922 void osc_cache_truncate_end(const struct lu_env *env, struct osc_extent *ext)
2925 struct osc_object *obj = ext->oe_obj;
2926 bool unplug = false;
2928 EASSERT(ext->oe_nr_pages > 0, ext);
2929 EASSERT(ext->oe_state == OES_TRUNC, ext);
2930 EASSERT(!ext->oe_urgent, ext);
2932 OSC_EXTENT_DUMP(D_CACHE, ext, "trunc -> cache.\n");
2933 osc_object_lock(obj);
2934 osc_extent_state_set(ext, OES_CACHE);
2935 if (ext->oe_fsync_wait && !ext->oe_urgent) {
2937 list_move_tail(&ext->oe_link, &obj->oo_urgent_exts);
2940 osc_update_pending(obj, OBD_BRW_WRITE, ext->oe_nr_pages);
2941 osc_object_unlock(obj);
2942 osc_extent_put(env, ext);
2945 osc_io_unplug_async(env, osc_cli(obj), obj);
2950 * Wait for extents in a specific range to be written out.
2951 * The caller must have called osc_cache_writeback_range() to issue IO
2952 * otherwise it will take a long time for this function to finish.
2954 * Caller must hold inode_mutex , or cancel exclusive dlm lock so that
2955 * nobody else can dirty this range of file while we're waiting for
2956 * extents to be written.
2958 int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
2959 pgoff_t start, pgoff_t end)
2961 struct osc_extent *ext;
2962 pgoff_t index = start;
2967 osc_object_lock(obj);
2968 ext = osc_extent_search(obj, index);
2970 ext = first_extent(obj);
2971 else if (ext->oe_end < index)
2972 ext = next_extent(ext);
2973 while (ext != NULL) {
2976 if (ext->oe_start > end)
2979 if (!ext->oe_fsync_wait) {
2980 ext = next_extent(ext);
2984 EASSERT(ergo(ext->oe_state == OES_CACHE,
2985 ext->oe_hp || ext->oe_urgent), ext);
2986 EASSERT(ergo(ext->oe_state == OES_ACTIVE,
2987 !ext->oe_hp && ext->oe_urgent), ext);
2989 index = ext->oe_end + 1;
2990 osc_extent_get(ext);
2991 osc_object_unlock(obj);
2993 rc = osc_extent_wait(env, ext, OES_INV);
2996 osc_extent_put(env, ext);
2999 osc_object_unlock(obj);
3001 OSC_IO_DEBUG(obj, "sync file range.\n");
3006 * Called to write out a range of osc object.
3008 * @hp : should be set this is caused by lock cancel;
3009 * @discard: is set if dirty pages should be dropped - file will be deleted or
3010 * truncated, this implies there is no partially discarding extents.
3012 * Return how many pages will be issued, or error code if error occurred.
3014 int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
3015 pgoff_t start, pgoff_t end, int hp, int discard)
3017 struct osc_extent *ext;
3018 struct list_head discard_list = LIST_HEAD_INIT(discard_list);
3019 bool unplug = false;
3023 osc_object_lock(obj);
3024 ext = osc_extent_search(obj, start);
3026 ext = first_extent(obj);
3027 else if (ext->oe_end < start)
3028 ext = next_extent(ext);
3029 while (ext != NULL) {
3030 if (ext->oe_start > end)
3033 ext->oe_fsync_wait = 1;
3034 switch (ext->oe_state) {
3036 result += ext->oe_nr_pages;
3038 struct list_head *list = NULL;
3040 EASSERT(!ext->oe_hp, ext);
3042 list = &obj->oo_hp_exts;
3043 } else if (!ext->oe_urgent) {
3045 list = &obj->oo_urgent_exts;
3048 list_move_tail(&ext->oe_link, list);
3051 /* the only discarder is lock cancelling, so
3052 * [start, end] must contain this extent */
3053 EASSERT(ext->oe_start >= start &&
3054 ext->oe_max_end <= end, ext);
3055 osc_extent_state_set(ext, OES_LOCKING);
3056 ext->oe_owner = current;
3057 list_move_tail(&ext->oe_link,
3059 osc_update_pending(obj, OBD_BRW_WRITE,
3064 /* It's pretty bad to wait for ACTIVE extents, because
3065 * we don't know how long we will wait for it to be
3066 * flushed since it may be blocked at awaiting more
3067 * grants. We do this for the correctness of fsync. */
3068 LASSERT(hp == 0 && discard == 0);
3072 /* this extent is being truncated, can't do anything
3073 * for it now. it will be set to urgent after truncate
3074 * is finished in osc_cache_truncate_end(). */
3078 ext = next_extent(ext);
3080 osc_object_unlock(obj);
3082 LASSERT(ergo(!discard, list_empty(&discard_list)));
3083 if (!list_empty(&discard_list)) {
3084 struct osc_extent *tmp;
3087 osc_list_maint(osc_cli(obj), obj);
3088 list_for_each_entry_safe(ext, tmp, &discard_list, oe_link) {
3089 list_del_init(&ext->oe_link);
3090 EASSERT(ext->oe_state == OES_LOCKING, ext);
3092 /* Discard caching pages. We don't actually write this
3093 * extent out but we complete it as if we did. */
3094 rc = osc_extent_make_ready(env, ext);
3095 if (unlikely(rc < 0)) {
3096 OSC_EXTENT_DUMP(D_ERROR, ext,
3097 "make_ready returned %d\n", rc);
3102 /* finish the extent as if the pages were sent */
3103 osc_extent_finish(env, ext, 0, 0);
3108 osc_io_unplug(env, osc_cli(obj), obj);
3110 if (hp || discard) {
3112 rc = osc_cache_wait_range(env, obj, start, end);
3113 if (result >= 0 && rc < 0)
3117 OSC_IO_DEBUG(obj, "pageout [%lu, %lu], %d.\n", start, end, result);
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);
3214 * Check if page @page is covered by an extra lock or discard it.
3216 static int check_and_discard_cb(const struct lu_env *env, struct cl_io *io,
3217 struct osc_page *ops, void *cbdata)
3219 struct osc_thread_info *info = osc_env_info(env);
3220 struct osc_object *osc = cbdata;
3223 index = osc_index(ops);
3224 if (index >= info->oti_fn_index) {
3225 struct ldlm_lock *tmp;
3226 struct cl_page *page = ops->ops_cl.cpl_page;
3228 /* refresh non-overlapped index */
3229 tmp = osc_dlmlock_at_pgoff(env, osc, index,
3230 OSC_DAP_FL_TEST_LOCK);
3232 __u64 end = tmp->l_policy_data.l_extent.end;
3233 /* Cache the first-non-overlapped index so as to skip
3234 * all pages within [index, oti_fn_index). This is safe
3235 * because if tmp lock is canceled, it will discard
3237 info->oti_fn_index = cl_index(osc2cl(osc), end + 1);
3238 if (end == OBD_OBJECT_EOF)
3239 info->oti_fn_index = CL_PAGE_EOF;
3241 } else if (cl_page_own(env, io, page) == 0) {
3242 /* discard the page */
3243 cl_page_discard(env, io, page);
3244 cl_page_disown(env, io, page);
3246 LASSERT(page->cp_state == CPS_FREEING);
3250 info->oti_next_index = index + 1;
3251 return CLP_GANG_OKAY;
3254 static int discard_cb(const struct lu_env *env, struct cl_io *io,
3255 struct osc_page *ops, void *cbdata)
3257 struct osc_thread_info *info = osc_env_info(env);
3258 struct cl_page *page = ops->ops_cl.cpl_page;
3260 /* page is top page. */
3261 info->oti_next_index = osc_index(ops) + 1;
3262 if (cl_page_own(env, io, page) == 0) {
3263 if (!ergo(page->cp_type == CPT_CACHEABLE,
3264 !PageDirty(cl_page_vmpage(page))))
3265 CL_PAGE_DEBUG(D_ERROR, env, page,
3266 "discard dirty page?\n");
3268 /* discard the page */
3269 cl_page_discard(env, io, page);
3270 cl_page_disown(env, io, page);
3272 LASSERT(page->cp_state == CPS_FREEING);
3275 return CLP_GANG_OKAY;
3279 * Discard pages protected by the given lock. This function traverses radix
3280 * tree to find all covering pages and discard them. If a page is being covered
3281 * by other locks, it should remain in cache.
3283 * If error happens on any step, the process continues anyway (the reasoning
3284 * behind this being that lock cancellation cannot be delayed indefinitely).
3286 int osc_lock_discard_pages(const struct lu_env *env, struct osc_object *osc,
3287 pgoff_t start, pgoff_t end, enum cl_lock_mode mode)
3289 struct osc_thread_info *info = osc_env_info(env);
3290 struct cl_io *io = &info->oti_io;
3291 osc_page_gang_cbt cb;
3297 io->ci_obj = cl_object_top(osc2cl(osc));
3298 io->ci_ignore_layout = 1;
3299 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
3303 cb = mode == CLM_READ ? check_and_discard_cb : discard_cb;
3304 info->oti_fn_index = info->oti_next_index = start;
3306 res = osc_page_gang_lookup(env, io, osc,
3307 info->oti_next_index, end, cb, osc);
3308 if (info->oti_next_index > end)
3311 if (res == CLP_GANG_RESCHED)
3313 } while (res != CLP_GANG_OKAY);
3315 cl_io_fini(env, io);