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staging/lustre/llite: fix 'data race condition' issues of lli_flags
[mirror_ubuntu-hirsute-kernel.git] / drivers / staging / lustre / lustre / osc / osc_cache.c
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d7e09d03
PT		 1/*
2 * GPL HEADER START
3 *
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
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.
9 *
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).
15 *
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19 *
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
22 * have any questions.
23 *
24 * GPL HEADER END
25 */
26/*
27 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
29 *
30 * Copyright (c) 2012, Intel Corporation.
31 *
32 */
33/*
34 * This file is part of Lustre, http://www.lustre.org/
35 * Lustre is a trademark of Sun Microsystems, Inc.
36 *
37 * osc cache management.
38 *
39 * Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
40 */
41
42#define DEBUG_SUBSYSTEM S_OSC
43
44#include "osc_cl_internal.h"
45#include "osc_internal.h"
46
47static int extent_debug; /* set it to be true for more debug */
48
49static void osc_update_pending(struct osc_object *obj, int cmd, int delta);
50static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
51 int state);
52static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
53 struct osc_async_page *oap, int sent, int rc);
54static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
55 int cmd);
56static int osc_refresh_count(const struct lu_env *env,
57 struct osc_async_page *oap, int cmd);
58static int osc_io_unplug_async(const struct lu_env *env,
59 struct client_obd *cli, struct osc_object *osc);
60static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
61 unsigned int lost_grant);
62
63static void osc_extent_tree_dump0(int level, struct osc_object *obj,
64 const char *func, int line);
65#define osc_extent_tree_dump(lvl, obj) \
66 osc_extent_tree_dump0(lvl, obj, __func__, __LINE__)
67
68/** \addtogroup osc
69 * @{
70 */
71
72/* ------------------ osc extent ------------------ */
73static inline char *ext_flags(struct osc_extent *ext, char *flags)
74{
75 char *buf = flags;
76 *buf++ = ext->oe_rw ? 'r' : 'w';
77 if (ext->oe_intree)
78 *buf++ = 'i';
79 if (ext->oe_srvlock)
80 *buf++ = 's';
81 if (ext->oe_hp)
82 *buf++ = 'h';
83 if (ext->oe_urgent)
84 *buf++ = 'u';
85 if (ext->oe_memalloc)
86 *buf++ = 'm';
87 if (ext->oe_trunc_pending)
88 *buf++ = 't';
89 if (ext->oe_fsync_wait)
90 *buf++ = 'Y';
91 *buf = 0;
92 return flags;
93}
94
95static inline char list_empty_marker(struct list_head *list)
96{
97 return list_empty(list) ? '-' : '+';
98}
99
100#define EXTSTR "[%lu -> %lu/%lu]"
101#define EXTPARA(ext) (ext)->oe_start, (ext)->oe_end, (ext)->oe_max_end
cad6fafa
BJ		 102static const char *oes_strings[] = {
103 "inv", "active", "cache", "locking", "lockdone", "rpc", "trunc", NULL };
d7e09d03
PT		 104
105#define OSC_EXTENT_DUMP(lvl, extent, fmt, ...) do { \
106 struct osc_extent *__ext = (extent); \
d7e09d03
PT		 107 char __buf[16]; \
108 \
109 CDEBUG(lvl, \
110 "extent %p@{" EXTSTR ", " \
111 "[%d|%d|%c|%s|%s|%p], [%d|%d|%c|%c|%p|%u|%p]} " fmt, \
112 /* ----- extent part 0 ----- */ \
113 __ext, EXTPARA(__ext), \
114 /* ----- part 1 ----- */ \
115 atomic_read(&__ext->oe_refc), \
116 atomic_read(&__ext->oe_users), \
117 list_empty_marker(&__ext->oe_link), \
cad6fafa 118 oes_strings[__ext->oe_state], ext_flags(__ext, __buf), \
d7e09d03
PT		 119 __ext->oe_obj, \
120 /* ----- part 2 ----- */ \
121 __ext->oe_grants, __ext->oe_nr_pages, \
122 list_empty_marker(&__ext->oe_pages), \
123 waitqueue_active(&__ext->oe_waitq) ? '+' : '-', \
124 __ext->oe_osclock, __ext->oe_mppr, __ext->oe_owner, \
125 /* ----- part 4 ----- */ \
126 ## __VA_ARGS__); \
127} while (0)
128
129#undef EASSERTF
130#define EASSERTF(expr, ext, fmt, args...) do { \
131 if (!(expr)) { \
cad6fafa
BJ		 132 OSC_EXTENT_DUMP(D_ERROR, (ext), fmt, ##args); \
133 osc_extent_tree_dump(D_ERROR, (ext)->oe_obj); \
d7e09d03 134 LASSERT(expr); \
cad6fafa 135 } \
d7e09d03
PT		 136} while (0)
137
138#undef EASSERT
139#define EASSERT(expr, ext) EASSERTF(expr, ext, "\n")
140
141static inline struct osc_extent *rb_extent(struct rb_node *n)
142{
143 if (n == NULL)
144 return NULL;
145
146 return container_of(n, struct osc_extent, oe_node);
147}
148
149static inline struct osc_extent *next_extent(struct osc_extent *ext)
150{
151 if (ext == NULL)
152 return NULL;
153
154 LASSERT(ext->oe_intree);
155 return rb_extent(rb_next(&ext->oe_node));
156}
157
158static inline struct osc_extent *prev_extent(struct osc_extent *ext)
159{
160 if (ext == NULL)
161 return NULL;
162
163 LASSERT(ext->oe_intree);
164 return rb_extent(rb_prev(&ext->oe_node));
165}
166
167static inline struct osc_extent *first_extent(struct osc_object *obj)
168{
169 return rb_extent(rb_first(&obj->oo_root));
170}
171
172/* object must be locked by caller. */
173static int osc_extent_sanity_check0(struct osc_extent *ext,
174 const char *func, const int line)
175{
176 struct osc_object *obj = ext->oe_obj;
177 struct osc_async_page *oap;
178 int page_count;
179 int rc = 0;
180
181 if (!osc_object_is_locked(obj))
182 GOTO(out, rc = 9);
183
184 if (ext->oe_state >= OES_STATE_MAX)
185 GOTO(out, rc = 10);
186
187 if (atomic_read(&ext->oe_refc) <= 0)
188 GOTO(out, rc = 20);
189
190 if (atomic_read(&ext->oe_refc) < atomic_read(&ext->oe_users))
191 GOTO(out, rc = 30);
192
193 switch (ext->oe_state) {
194 case OES_INV:
195 if (ext->oe_nr_pages > 0 || !list_empty(&ext->oe_pages))
196 GOTO(out, rc = 35);
197 GOTO(out, rc = 0);
198 break;
199 case OES_ACTIVE:
200 if (atomic_read(&ext->oe_users) == 0)
201 GOTO(out, rc = 40);
202 if (ext->oe_hp)
203 GOTO(out, rc = 50);
204 if (ext->oe_fsync_wait && !ext->oe_urgent)
205 GOTO(out, rc = 55);
206 break;
207 case OES_CACHE:
208 if (ext->oe_grants == 0)
209 GOTO(out, rc = 60);
210 if (ext->oe_fsync_wait && !ext->oe_urgent && !ext->oe_hp)
211 GOTO(out, rc = 65);
212 default:
213 if (atomic_read(&ext->oe_users) > 0)
214 GOTO(out, rc = 70);
215 }
216
217 if (ext->oe_max_end < ext->oe_end || ext->oe_end < ext->oe_start)
218 GOTO(out, rc = 80);
219
220 if (ext->oe_osclock == NULL && ext->oe_grants > 0)
221 GOTO(out, rc = 90);
222
223 if (ext->oe_osclock) {
224 struct cl_lock_descr *descr;
225 descr = &ext->oe_osclock->cll_descr;
226 if (!(descr->cld_start <= ext->oe_start &&
227 descr->cld_end >= ext->oe_max_end))
228 GOTO(out, rc = 100);
229 }
230
231 if (ext->oe_nr_pages > ext->oe_mppr)
232 GOTO(out, rc = 105);
233
234 /* Do not verify page list if extent is in RPC. This is because an
235 * in-RPC extent is supposed to be exclusively accessible w/o lock. */
236 if (ext->oe_state > OES_CACHE)
237 GOTO(out, rc = 0);
238
239 if (!extent_debug)
240 GOTO(out, rc = 0);
241
242 page_count = 0;
243 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
244 pgoff_t index = oap2cl_page(oap)->cp_index;
245 ++page_count;
246 if (index > ext->oe_end || index < ext->oe_start)
247 GOTO(out, rc = 110);
248 }
249 if (page_count != ext->oe_nr_pages)
250 GOTO(out, rc = 120);
251
252out:
253 if (rc != 0)
254 OSC_EXTENT_DUMP(D_ERROR, ext,
255 "%s:%d sanity check %p failed with rc = %d\n",
256 func, line, ext, rc);
257 return rc;
258}
259
260#define sanity_check_nolock(ext) \
261 osc_extent_sanity_check0(ext, __func__, __LINE__)
262
263#define sanity_check(ext) ({ \
264 int __res; \
265 osc_object_lock((ext)->oe_obj); \
266 __res = sanity_check_nolock(ext); \
267 osc_object_unlock((ext)->oe_obj); \
268 __res; \
269})
270
271
272/**
273 * sanity check - to make sure there is no overlapped extent in the tree.
274 */
275static int osc_extent_is_overlapped(struct osc_object *obj,
276 struct osc_extent *ext)
277{
278 struct osc_extent *tmp;
279
280 LASSERT(osc_object_is_locked(obj));
281
282 if (!extent_debug)
283 return 0;
284
285 for (tmp = first_extent(obj); tmp != NULL; tmp = next_extent(tmp)) {
286 if (tmp == ext)
287 continue;
288 if (tmp->oe_end >= ext->oe_start &&
289 tmp->oe_start <= ext->oe_end)
290 return 1;
291 }
292 return 0;
293}
294
295static void osc_extent_state_set(struct osc_extent *ext, int state)
296{
297 LASSERT(osc_object_is_locked(ext->oe_obj));
298 LASSERT(state >= OES_INV && state < OES_STATE_MAX);
299
300 /* Never try to sanity check a state changing extent :-) */
301 /* LASSERT(sanity_check_nolock(ext) == 0); */
302
303 /* TODO: validate the state machine */
304 ext->oe_state = state;
305 wake_up_all(&ext->oe_waitq);
306}
307
308static struct osc_extent *osc_extent_alloc(struct osc_object *obj)
309{
310 struct osc_extent *ext;
311
312 OBD_SLAB_ALLOC_PTR_GFP(ext, osc_extent_kmem, GFP_IOFS);
313 if (ext == NULL)
314 return NULL;
315
316 RB_CLEAR_NODE(&ext->oe_node);
317 ext->oe_obj = obj;
318 atomic_set(&ext->oe_refc, 1);
319 atomic_set(&ext->oe_users, 0);
320 INIT_LIST_HEAD(&ext->oe_link);
321 ext->oe_state = OES_INV;
322 INIT_LIST_HEAD(&ext->oe_pages);
323 init_waitqueue_head(&ext->oe_waitq);
324 ext->oe_osclock = NULL;
325
326 return ext;
327}
328
329static void osc_extent_free(struct osc_extent *ext)
330{
331 OBD_SLAB_FREE_PTR(ext, osc_extent_kmem);
332}
333
334static struct osc_extent *osc_extent_get(struct osc_extent *ext)
335{
336 LASSERT(atomic_read(&ext->oe_refc) >= 0);
337 atomic_inc(&ext->oe_refc);
338 return ext;
339}
340
341static void osc_extent_put(const struct lu_env *env, struct osc_extent *ext)
342{
343 LASSERT(atomic_read(&ext->oe_refc) > 0);
344 if (atomic_dec_and_test(&ext->oe_refc)) {
345 LASSERT(list_empty(&ext->oe_link));
346 LASSERT(atomic_read(&ext->oe_users) == 0);
347 LASSERT(ext->oe_state == OES_INV);
348 LASSERT(!ext->oe_intree);
349
350 if (ext->oe_osclock) {
351 cl_lock_put(env, ext->oe_osclock);
352 ext->oe_osclock = NULL;
353 }
354 osc_extent_free(ext);
355 }
356}
357
358/**
359 * osc_extent_put_trust() is a special version of osc_extent_put() when
360 * it's known that the caller is not the last user. This is to address the
361 * problem of lacking of lu_env ;-).
362 */
363static void osc_extent_put_trust(struct osc_extent *ext)
364{
365 LASSERT(atomic_read(&ext->oe_refc) > 1);
366 LASSERT(osc_object_is_locked(ext->oe_obj));
367 atomic_dec(&ext->oe_refc);
368}
369
370/**
371 * Return the extent which includes pgoff @index, or return the greatest
372 * previous extent in the tree.
373 */
374static struct osc_extent *osc_extent_search(struct osc_object *obj,
375 pgoff_t index)
376{
377 struct rb_node *n = obj->oo_root.rb_node;
378 struct osc_extent *tmp, *p = NULL;
379
380 LASSERT(osc_object_is_locked(obj));
381 while (n != NULL) {
382 tmp = rb_extent(n);
383 if (index < tmp->oe_start) {
384 n = n->rb_left;
385 } else if (index > tmp->oe_end) {
386 p = rb_extent(n);
387 n = n->rb_right;
388 } else {
389 return tmp;
390 }
391 }
392 return p;
393}
394
395/*
396 * Return the extent covering @index, otherwise return NULL.
397 * caller must have held object lock.
398 */
399static struct osc_extent *osc_extent_lookup(struct osc_object *obj,
400 pgoff_t index)
401{
402 struct osc_extent *ext;
403
404 ext = osc_extent_search(obj, index);
405 if (ext != NULL && ext->oe_start <= index && index <= ext->oe_end)
406 return osc_extent_get(ext);
407 return NULL;
408}
409
410/* caller must have held object lock. */
411static void osc_extent_insert(struct osc_object *obj, struct osc_extent *ext)
412{
413 struct rb_node **n = &obj->oo_root.rb_node;
414 struct rb_node *parent = NULL;
415 struct osc_extent *tmp;
416
417 LASSERT(ext->oe_intree == 0);
418 LASSERT(ext->oe_obj == obj);
419 LASSERT(osc_object_is_locked(obj));
420 while (*n != NULL) {
421 tmp = rb_extent(*n);
422 parent = *n;
423
424 if (ext->oe_end < tmp->oe_start)
425 n = &(*n)->rb_left;
426 else if (ext->oe_start > tmp->oe_end)
427 n = &(*n)->rb_right;
428 else
429 EASSERTF(0, tmp, EXTSTR, EXTPARA(ext));
430 }
431 rb_link_node(&ext->oe_node, parent, n);
432 rb_insert_color(&ext->oe_node, &obj->oo_root);
433 osc_extent_get(ext);
434 ext->oe_intree = 1;
435}
436
437/* caller must have held object lock. */
438static void osc_extent_erase(struct osc_extent *ext)
439{
440 struct osc_object *obj = ext->oe_obj;
441 LASSERT(osc_object_is_locked(obj));
442 if (ext->oe_intree) {
443 rb_erase(&ext->oe_node, &obj->oo_root);
444 ext->oe_intree = 0;
445 /* rbtree held a refcount */
446 osc_extent_put_trust(ext);
447 }
448}
449
450static struct osc_extent *osc_extent_hold(struct osc_extent *ext)
451{
452 struct osc_object *obj = ext->oe_obj;
453
454 LASSERT(osc_object_is_locked(obj));
455 LASSERT(ext->oe_state == OES_ACTIVE || ext->oe_state == OES_CACHE);
456 if (ext->oe_state == OES_CACHE) {
457 osc_extent_state_set(ext, OES_ACTIVE);
458 osc_update_pending(obj, OBD_BRW_WRITE, -ext->oe_nr_pages);
459 }
460 atomic_inc(&ext->oe_users);
461 list_del_init(&ext->oe_link);
462 return osc_extent_get(ext);
463}
464
465static void __osc_extent_remove(struct osc_extent *ext)
466{
467 LASSERT(osc_object_is_locked(ext->oe_obj));
468 LASSERT(list_empty(&ext->oe_pages));
469 osc_extent_erase(ext);
470 list_del_init(&ext->oe_link);
471 osc_extent_state_set(ext, OES_INV);
472 OSC_EXTENT_DUMP(D_CACHE, ext, "destroyed.\n");
473}
474
475static void osc_extent_remove(struct osc_extent *ext)
476{
477 struct osc_object *obj = ext->oe_obj;
478
479 osc_object_lock(obj);
480 __osc_extent_remove(ext);
481 osc_object_unlock(obj);
482}
483
484/**
485 * This function is used to merge extents to get better performance. It checks
486 * if @cur and @victim are contiguous at chunk level.
487 */
488static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
489 struct osc_extent *victim)
490{
491 struct osc_object *obj = cur->oe_obj;
492 pgoff_t chunk_start;
493 pgoff_t chunk_end;
494 int ppc_bits;
495
496 LASSERT(cur->oe_state == OES_CACHE);
497 LASSERT(osc_object_is_locked(obj));
498 if (victim == NULL)
499 return -EINVAL;
500
501 if (victim->oe_state != OES_CACHE || victim->oe_fsync_wait)
502 return -EBUSY;
503
504 if (cur->oe_max_end != victim->oe_max_end)
505 return -ERANGE;
506
507 LASSERT(cur->oe_osclock == victim->oe_osclock);
508 ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_CACHE_SHIFT;
509 chunk_start = cur->oe_start >> ppc_bits;
510 chunk_end = cur->oe_end >> ppc_bits;
511 if (chunk_start != (victim->oe_end >> ppc_bits) + 1 &&
512 chunk_end + 1 != victim->oe_start >> ppc_bits)
513 return -ERANGE;
514
515 OSC_EXTENT_DUMP(D_CACHE, victim, "will be merged by %p.\n", cur);
516
517 cur->oe_start = min(cur->oe_start, victim->oe_start);
518 cur->oe_end = max(cur->oe_end, victim->oe_end);
519 cur->oe_grants += victim->oe_grants;
520 cur->oe_nr_pages += victim->oe_nr_pages;
521 /* only the following bits are needed to merge */
522 cur->oe_urgent |= victim->oe_urgent;
523 cur->oe_memalloc |= victim->oe_memalloc;
524 list_splice_init(&victim->oe_pages, &cur->oe_pages);
525 list_del_init(&victim->oe_link);
526 victim->oe_nr_pages = 0;
527
528 osc_extent_get(victim);
529 __osc_extent_remove(victim);
530 osc_extent_put(env, victim);
531
532 OSC_EXTENT_DUMP(D_CACHE, cur, "after merging %p.\n", victim);
533 return 0;
534}
535
536/**
537 * Drop user count of osc_extent, and unplug IO asynchronously.
538 */
539int osc_extent_release(const struct lu_env *env, struct osc_extent *ext)
540{
541 struct osc_object *obj = ext->oe_obj;
542 int rc = 0;
543 ENTRY;
544
545 LASSERT(atomic_read(&ext->oe_users) > 0);
546 LASSERT(sanity_check(ext) == 0);
547 LASSERT(ext->oe_grants > 0);
548
549 if (atomic_dec_and_lock(&ext->oe_users, &obj->oo_lock)) {
550 LASSERT(ext->oe_state == OES_ACTIVE);
551 if (ext->oe_trunc_pending) {
552 /* a truncate process is waiting for this extent.
553 * This may happen due to a race, check
554 * osc_cache_truncate_start(). */
555 osc_extent_state_set(ext, OES_TRUNC);
556 ext->oe_trunc_pending = 0;
557 } else {
558 osc_extent_state_set(ext, OES_CACHE);
559 osc_update_pending(obj, OBD_BRW_WRITE,
560 ext->oe_nr_pages);
561
562 /* try to merge the previous and next extent. */
563 osc_extent_merge(env, ext, prev_extent(ext));
564 osc_extent_merge(env, ext, next_extent(ext));
565
566 if (ext->oe_urgent)
567 list_move_tail(&ext->oe_link,
568 &obj->oo_urgent_exts);
569 }
570 osc_object_unlock(obj);
571
572 osc_io_unplug_async(env, osc_cli(obj), obj);
573 }
574 osc_extent_put(env, ext);
575 RETURN(rc);
576}
577
578static inline int overlapped(struct osc_extent *ex1, struct osc_extent *ex2)
579{
580 return !(ex1->oe_end < ex2->oe_start || ex2->oe_end < ex1->oe_start);
581}
582
583/**
584 * Find or create an extent which includes @index, core function to manage
585 * extent tree.
586 */
587struct osc_extent *osc_extent_find(const struct lu_env *env,
588 struct osc_object *obj, pgoff_t index,
589 int *grants)
590
591{
592 struct client_obd *cli = osc_cli(obj);
593 struct cl_lock *lock;
594 struct osc_extent *cur;
595 struct osc_extent *ext;
596 struct osc_extent *conflict = NULL;
597 struct osc_extent *found = NULL;
598 pgoff_t chunk;
599 pgoff_t max_end;
600 int max_pages; /* max_pages_per_rpc */
601 int chunksize;
602 int ppc_bits; /* pages per chunk bits */
603 int chunk_mask;
604 int rc;
605 ENTRY;
606
607 cur = osc_extent_alloc(obj);
608 if (cur == NULL)
609 RETURN(ERR_PTR(-ENOMEM));
610
611 lock = cl_lock_at_pgoff(env, osc2cl(obj), index, NULL, 1, 0);
612 LASSERT(lock != NULL);
613 LASSERT(lock->cll_descr.cld_mode >= CLM_WRITE);
614
615 LASSERT(cli->cl_chunkbits >= PAGE_CACHE_SHIFT);
616 ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
617 chunk_mask = ~((1 << ppc_bits) - 1);
618 chunksize = 1 << cli->cl_chunkbits;
619 chunk = index >> ppc_bits;
620
621 /* align end to rpc edge, rpc size may not be a power 2 integer. */
622 max_pages = cli->cl_max_pages_per_rpc;
623 LASSERT((max_pages & ~chunk_mask) == 0);
624 max_end = index - (index % max_pages) + max_pages - 1;
625 max_end = min_t(pgoff_t, max_end, lock->cll_descr.cld_end);
626
627 /* initialize new extent by parameters so far */
628 cur->oe_max_end = max_end;
629 cur->oe_start = index & chunk_mask;
630 cur->oe_end = ((index + ~chunk_mask + 1) & chunk_mask) - 1;
631 if (cur->oe_start < lock->cll_descr.cld_start)
632 cur->oe_start = lock->cll_descr.cld_start;
633 if (cur->oe_end > max_end)
634 cur->oe_end = max_end;
635 cur->oe_osclock = lock;
636 cur->oe_grants = 0;
637 cur->oe_mppr = max_pages;
638
639 /* grants has been allocated by caller */
640 LASSERTF(*grants >= chunksize + cli->cl_extent_tax,
641 "%u/%u/%u.\n", *grants, chunksize, cli->cl_extent_tax);
642 LASSERTF((max_end - cur->oe_start) < max_pages, EXTSTR, EXTPARA(cur));
643
644restart:
645 osc_object_lock(obj);
646 ext = osc_extent_search(obj, cur->oe_start);
647 if (ext == NULL)
648 ext = first_extent(obj);
649 while (ext != NULL) {
650 loff_t ext_chk_start = ext->oe_start >> ppc_bits;
651 loff_t ext_chk_end = ext->oe_end >> ppc_bits;
652
653 LASSERT(sanity_check_nolock(ext) == 0);
654 if (chunk > ext_chk_end + 1)
655 break;
656
657 /* if covering by different locks, no chance to match */
658 if (lock != ext->oe_osclock) {
659 EASSERTF(!overlapped(ext, cur), ext,
660 EXTSTR, EXTPARA(cur));
661
662 ext = next_extent(ext);
663 continue;
664 }
665
666 /* discontiguous chunks? */
667 if (chunk + 1 < ext_chk_start) {
668 ext = next_extent(ext);
669 continue;
670 }
671
672 /* ok, from now on, ext and cur have these attrs:
673 * 1. covered by the same lock
674 * 2. contiguous at chunk level or overlapping. */
675
676 if (overlapped(ext, cur)) {
677 /* cur is the minimum unit, so overlapping means
678 * full contain. */
679 EASSERTF((ext->oe_start <= cur->oe_start &&
680 ext->oe_end >= cur->oe_end),
681 ext, EXTSTR, EXTPARA(cur));
682
683 if (ext->oe_state > OES_CACHE || ext->oe_fsync_wait) {
684 /* for simplicity, we wait for this extent to
685 * finish before going forward. */
686 conflict = osc_extent_get(ext);
687 break;
688 }
689
690 found = osc_extent_hold(ext);
691 break;
692 }
693
694 /* non-overlapped extent */
695 if (ext->oe_state != OES_CACHE || ext->oe_fsync_wait) {
696 /* we can't do anything for a non OES_CACHE extent, or
697 * if there is someone waiting for this extent to be
698 * flushed, try next one. */
699 ext = next_extent(ext);
700 continue;
701 }
702
703 /* check if they belong to the same rpc slot before trying to
704 * merge. the extents are not overlapped and contiguous at
705 * chunk level to get here. */
706 if (ext->oe_max_end != max_end) {
707 /* if they don't belong to the same RPC slot or
708 * max_pages_per_rpc has ever changed, do not merge. */
709 ext = next_extent(ext);
710 continue;
711 }
712
713 /* it's required that an extent must be contiguous at chunk
714 * level so that we know the whole extent is covered by grant
715 * (the pages in the extent are NOT required to be contiguous).
716 * Otherwise, it will be too much difficult to know which
717 * chunks have grants allocated. */
718
719 /* try to do front merge - extend ext's start */
720 if (chunk + 1 == ext_chk_start) {
721 /* ext must be chunk size aligned */
722 EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
723
724 /* pull ext's start back to cover cur */
725 ext->oe_start = cur->oe_start;
726 ext->oe_grants += chunksize;
727 *grants -= chunksize;
728
729 found = osc_extent_hold(ext);
730 } else if (chunk == ext_chk_end + 1) {
731 /* rear merge */
732 ext->oe_end = cur->oe_end;
733 ext->oe_grants += chunksize;
734 *grants -= chunksize;
735
736 /* try to merge with the next one because we just fill
737 * in a gap */
738 if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
739 /* we can save extent tax from next extent */
740 *grants += cli->cl_extent_tax;
741
742 found = osc_extent_hold(ext);
743 }
744 if (found != NULL)
745 break;
746
747 ext = next_extent(ext);
748 }
749
750 osc_extent_tree_dump(D_CACHE, obj);
751 if (found != NULL) {
752 LASSERT(conflict == NULL);
753 if (!IS_ERR(found)) {
754 LASSERT(found->oe_osclock == cur->oe_osclock);
755 OSC_EXTENT_DUMP(D_CACHE, found,
756 "found caching ext for %lu.\n", index);
757 }
758 } else if (conflict == NULL) {
759 /* create a new extent */
760 EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
761 cur->oe_grants = chunksize + cli->cl_extent_tax;
762 *grants -= cur->oe_grants;
763 LASSERT(*grants >= 0);
764
765 cur->oe_state = OES_CACHE;
766 found = osc_extent_hold(cur);
767 osc_extent_insert(obj, cur);
768 OSC_EXTENT_DUMP(D_CACHE, cur, "add into tree %lu/%lu.\n",
769 index, lock->cll_descr.cld_end);
770 }
771 osc_object_unlock(obj);
772
773 if (conflict != NULL) {
774 LASSERT(found == NULL);
775
776 /* waiting for IO to finish. Please notice that it's impossible
777 * to be an OES_TRUNC extent. */
778 rc = osc_extent_wait(env, conflict, OES_INV);
779 osc_extent_put(env, conflict);
780 conflict = NULL;
781 if (rc < 0)
782 GOTO(out, found = ERR_PTR(rc));
783
784 goto restart;
785 }
786 EXIT;
787
788out:
789 osc_extent_put(env, cur);
790 LASSERT(*grants >= 0);
791 return found;
792}
793
794/**
795 * Called when IO is finished to an extent.
796 */
797int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
798 int sent, int rc)
799{
800 struct client_obd *cli = osc_cli(ext->oe_obj);
801 struct osc_async_page *oap;
802 struct osc_async_page *tmp;
803 int nr_pages = ext->oe_nr_pages;
804 int lost_grant = 0;
805 int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
806 __u64 last_off = 0;
807 int last_count = -1;
808 ENTRY;
809
810 OSC_EXTENT_DUMP(D_CACHE, ext, "extent finished.\n");
811
812 ext->oe_rc = rc ?: ext->oe_nr_pages;
813 EASSERT(ergo(rc == 0, ext->oe_state == OES_RPC), ext);
814 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
815 oap_pending_item) {
816 list_del_init(&oap->oap_rpc_item);
817 list_del_init(&oap->oap_pending_item);
818 if (last_off <= oap->oap_obj_off) {
819 last_off = oap->oap_obj_off;
820 last_count = oap->oap_count;
821 }
822
823 --ext->oe_nr_pages;
824 osc_ap_completion(env, cli, oap, sent, rc);
825 }
826 EASSERT(ext->oe_nr_pages == 0, ext);
827
828 if (!sent) {
829 lost_grant = ext->oe_grants;
830 } else if (blocksize < PAGE_CACHE_SIZE &&
831 last_count != PAGE_CACHE_SIZE) {
832 /* For short writes we shouldn't count parts of pages that
833 * span a whole chunk on the OST side, or our accounting goes
834 * wrong. Should match the code in filter_grant_check. */
835 int offset = oap->oap_page_off & ~CFS_PAGE_MASK;
836 int count = oap->oap_count + (offset & (blocksize - 1));
837 int end = (offset + oap->oap_count) & (blocksize - 1);
838 if (end)
839 count += blocksize - end;
840
841 lost_grant = PAGE_CACHE_SIZE - count;
842 }
843 if (ext->oe_grants > 0)
844 osc_free_grant(cli, nr_pages, lost_grant);
845
846 osc_extent_remove(ext);
847 /* put the refcount for RPC */
848 osc_extent_put(env, ext);
849 RETURN(0);
850}
851
852static int extent_wait_cb(struct osc_extent *ext, int state)
853{
854 int ret;
855
856 osc_object_lock(ext->oe_obj);
857 ret = ext->oe_state == state;
858 osc_object_unlock(ext->oe_obj);
859
860 return ret;
861}
862
863/**
864 * Wait for the extent's state to become @state.
865 */
866static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
867 int state)
868{
869 struct osc_object *obj = ext->oe_obj;
870 struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(600), NULL,
871 LWI_ON_SIGNAL_NOOP, NULL);
872 int rc = 0;
873 ENTRY;
874
875 osc_object_lock(obj);
876 LASSERT(sanity_check_nolock(ext) == 0);
877 /* `Kick' this extent only if the caller is waiting for it to be
878 * written out. */
879 if (state == OES_INV && !ext->oe_urgent && !ext->oe_hp) {
880 if (ext->oe_state == OES_ACTIVE) {
881 ext->oe_urgent = 1;
882 } else if (ext->oe_state == OES_CACHE) {
883 ext->oe_urgent = 1;
884 osc_extent_hold(ext);
885 rc = 1;
886 }
887 }
888 osc_object_unlock(obj);
889 if (rc == 1)
890 osc_extent_release(env, ext);
891
892 /* wait for the extent until its state becomes @state */
893 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state), &lwi);
894 if (rc == -ETIMEDOUT) {
895 OSC_EXTENT_DUMP(D_ERROR, ext,
896 "%s: wait ext to %d timedout, recovery in progress?\n",
897 osc_export(obj)->exp_obd->obd_name, state);
898
899 lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
900 rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state),
901 &lwi);
902 }
903 if (rc == 0 && ext->oe_rc < 0)
904 rc = ext->oe_rc;
905 RETURN(rc);
906}
907
908/**
909 * Discard pages with index greater than @size. If @ext is overlapped with
910 * @size, then partial truncate happens.
911 */
912static int osc_extent_truncate(struct osc_extent *ext, pgoff_t trunc_index,
913 bool partial)
914{
915 struct cl_env_nest nest;
916 struct lu_env *env;
917 struct cl_io *io;
918 struct osc_object *obj = ext->oe_obj;
919 struct client_obd *cli = osc_cli(obj);
920 struct osc_async_page *oap;
921 struct osc_async_page *tmp;
922 int pages_in_chunk = 0;
923 int ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
924 __u64 trunc_chunk = trunc_index >> ppc_bits;
925 int grants = 0;
926 int nr_pages = 0;
927 int rc = 0;
928 ENTRY;
929
930 LASSERT(sanity_check(ext) == 0);
931 LASSERT(ext->oe_state == OES_TRUNC);
932 LASSERT(!ext->oe_urgent);
933
934 /* Request new lu_env.
935 * We can't use that env from osc_cache_truncate_start() because
936 * it's from lov_io_sub and not fully initialized. */
937 env = cl_env_nested_get(&nest);
938 io = &osc_env_info(env)->oti_io;
939 io->ci_obj = cl_object_top(osc2cl(obj));
940 rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
941 if (rc < 0)
942 GOTO(out, rc);
943
944 /* discard all pages with index greater then trunc_index */
945 list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
946 oap_pending_item) {
947 struct cl_page *sub = oap2cl_page(oap);
948 struct cl_page *page = cl_page_top(sub);
949
950 LASSERT(list_empty(&oap->oap_rpc_item));
951
952 /* only discard the pages with their index greater than
953 * trunc_index, and ... */
954 if (sub->cp_index < trunc_index ||
955 (sub->cp_index == trunc_index && partial)) {
956 /* accounting how many pages remaining in the chunk
957 * so that we can calculate grants correctly. */
958 if (sub->cp_index >> ppc_bits == trunc_chunk)
959 ++pages_in_chunk;
960 continue;
961 }
962
963 list_del_init(&oap->oap_pending_item);
964
965 cl_page_get(page);
966 lu_ref_add(&page->cp_reference, "truncate", current);
967
968 if (cl_page_own(env, io, page) == 0) {
969 cl_page_unmap(env, io, page);
970 cl_page_discard(env, io, page);
971 cl_page_disown(env, io, page);
972 } else {
973 LASSERT(page->cp_state == CPS_FREEING);
974 LASSERT(0);
975 }
976
977 lu_ref_del(&page->cp_reference, "truncate", current);
978 cl_page_put(env, page);
979
980 --ext->oe_nr_pages;
981 ++nr_pages;
982 }
983 EASSERTF(ergo(ext->oe_start >= trunc_index + !!partial,
984 ext->oe_nr_pages == 0),
985 ext, "trunc_index %lu, partial %d\n", trunc_index, partial);
986
987 osc_object_lock(obj);
988 if (ext->oe_nr_pages == 0) {
989 LASSERT(pages_in_chunk == 0);
990 grants = ext->oe_grants;
991 ext->oe_grants = 0;
992 } else { /* calculate how many grants we can free */
993 int chunks = (ext->oe_end >> ppc_bits) - trunc_chunk;
994 pgoff_t last_index;
995
996
997 /* if there is no pages in this chunk, we can also free grants
998 * for the last chunk */
999 if (pages_in_chunk == 0) {
1000 /* if this is the 1st chunk and no pages in this chunk,
1001 * ext->oe_nr_pages must be zero, so we should be in
1002 * the other if-clause. */
1003 LASSERT(trunc_chunk > 0);
1004 --trunc_chunk;
1005 ++chunks;
1006 }
1007
1008 /* this is what we can free from this extent */
1009 grants = chunks << cli->cl_chunkbits;
1010 ext->oe_grants -= grants;
1011 last_index = ((trunc_chunk + 1) << ppc_bits) - 1;
1012 ext->oe_end = min(last_index, ext->oe_max_end);
1013 LASSERT(ext->oe_end >= ext->oe_start);
1014 LASSERT(ext->oe_grants > 0);
1015 }
1016 osc_object_unlock(obj);
1017
1018 if (grants > 0 || nr_pages > 0)
1019 osc_free_grant(cli, nr_pages, grants);
1020
1021out:
1022 cl_io_fini(env, io);
1023 cl_env_nested_put(&nest, env);
1024 RETURN(rc);
1025}
1026
1027/**
1028 * This function is used to make the extent prepared for transfer.
1029 * A race with flusing page - ll_writepage() has to be handled cautiously.
1030 */
1031static int osc_extent_make_ready(const struct lu_env *env,
1032 struct osc_extent *ext)
1033{
1034 struct osc_async_page *oap;
1035 struct osc_async_page *last = NULL;
1036 struct osc_object *obj = ext->oe_obj;
1037 int page_count = 0;
1038 int rc;
1039 ENTRY;
1040
1041 /* we're going to grab page lock, so object lock must not be taken. */
1042 LASSERT(sanity_check(ext) == 0);
1043 /* in locking state, any process should not touch this extent. */
1044 EASSERT(ext->oe_state == OES_LOCKING, ext);
1045 EASSERT(ext->oe_owner != NULL, ext);
1046
1047 OSC_EXTENT_DUMP(D_CACHE, ext, "make ready\n");
1048
1049 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1050 ++page_count;
1051 if (last == NULL || last->oap_obj_off < oap->oap_obj_off)
1052 last = oap;
1053
1054 /* checking ASYNC_READY is race safe */
1055 if ((oap->oap_async_flags & ASYNC_READY) != 0)
1056 continue;
1057
1058 rc = osc_make_ready(env, oap, OBD_BRW_WRITE);
1059 switch (rc) {
1060 case 0:
1061 spin_lock(&oap->oap_lock);
1062 oap->oap_async_flags |= ASYNC_READY;
1063 spin_unlock(&oap->oap_lock);
1064 break;
1065 case -EALREADY:
1066 LASSERT((oap->oap_async_flags & ASYNC_READY) != 0);
1067 break;
1068 default:
1069 LASSERTF(0, "unknown return code: %d\n", rc);
1070 }
1071 }
1072
1073 LASSERT(page_count == ext->oe_nr_pages);
1074 LASSERT(last != NULL);
1075 /* the last page is the only one we need to refresh its count by
1076 * the size of file. */
1077 if (!(last->oap_async_flags & ASYNC_COUNT_STABLE)) {
1078 last->oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE);
1079 LASSERT(last->oap_count > 0);
1080 LASSERT(last->oap_page_off + last->oap_count <= PAGE_CACHE_SIZE);
1081 last->oap_async_flags |= ASYNC_COUNT_STABLE;
1082 }
1083
1084 /* for the rest of pages, we don't need to call osf_refresh_count()
1085 * because it's known they are not the last page */
1086 list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
1087 if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
1088 oap->oap_count = PAGE_CACHE_SIZE - oap->oap_page_off;
1089 oap->oap_async_flags |= ASYNC_COUNT_STABLE;
1090 }
1091 }
1092
1093 osc_object_lock(obj);
1094 osc_extent_state_set(ext, OES_RPC);
1095 osc_object_unlock(obj);
1096 /* get a refcount for RPC. */
1097 osc_extent_get(ext);
1098
1099 RETURN(0);
1100}
1101
1102/**
1103 * Quick and simple version of osc_extent_find(). This function is frequently
1104 * called to expand the extent for the same IO. To expand the extent, the
1105 * page index must be in the same or next chunk of ext->oe_end.
1106 */
1107static int osc_extent_expand(struct osc_extent *ext, pgoff_t index, int *grants)
1108{
1109 struct osc_object *obj = ext->oe_obj;
1110 struct client_obd *cli = osc_cli(obj);
1111 struct osc_extent *next;
1112 int ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
1113 pgoff_t chunk = index >> ppc_bits;
1114 pgoff_t end_chunk;
1115 pgoff_t end_index;
1116 int chunksize = 1 << cli->cl_chunkbits;
1117 int rc = 0;
1118 ENTRY;
1119
1120 LASSERT(ext->oe_max_end >= index && ext->oe_start <= index);
1121 osc_object_lock(obj);
1122 LASSERT(sanity_check_nolock(ext) == 0);
1123 end_chunk = ext->oe_end >> ppc_bits;
1124 if (chunk > end_chunk + 1)
1125 GOTO(out, rc = -ERANGE);
1126
1127 if (end_chunk >= chunk)
1128 GOTO(out, rc = 0);
1129
1130 LASSERT(end_chunk + 1 == chunk);
1131 /* try to expand this extent to cover @index */
1132 end_index = min(ext->oe_max_end, ((chunk + 1) << ppc_bits) - 1);
1133
1134 next = next_extent(ext);
1135 if (next != NULL && next->oe_start <= end_index)
1136 /* complex mode - overlapped with the next extent,
1137 * this case will be handled by osc_extent_find() */
1138 GOTO(out, rc = -EAGAIN);
1139
1140 ext->oe_end = end_index;
1141 ext->oe_grants += chunksize;
1142 *grants -= chunksize;
1143 LASSERT(*grants >= 0);
1144 EASSERTF(osc_extent_is_overlapped(obj, ext) == 0, ext,
1145 "overlapped after expanding for %lu.\n", index);
1146 EXIT;
1147
1148out:
1149 osc_object_unlock(obj);
1150 RETURN(rc);
1151}
1152
1153static void osc_extent_tree_dump0(int level, struct osc_object *obj,
1154 const char *func, int line)
1155{
1156 struct osc_extent *ext;
1157 int cnt;
1158
1159 CDEBUG(level, "Dump object %p extents at %s:%d, mppr: %u.\n",
1160 obj, func, line, osc_cli(obj)->cl_max_pages_per_rpc);
1161
1162 /* osc_object_lock(obj); */
1163 cnt = 1;
1164 for (ext = first_extent(obj); ext != NULL; ext = next_extent(ext))
1165 OSC_EXTENT_DUMP(level, ext, "in tree %d.\n", cnt++);
1166
1167 cnt = 1;
1168 list_for_each_entry(ext, &obj->oo_hp_exts, oe_link)
1169 OSC_EXTENT_DUMP(level, ext, "hp %d.\n", cnt++);
1170
1171 cnt = 1;
1172 list_for_each_entry(ext, &obj->oo_urgent_exts, oe_link)
1173 OSC_EXTENT_DUMP(level, ext, "urgent %d.\n", cnt++);
1174
1175 cnt = 1;
1176 list_for_each_entry(ext, &obj->oo_reading_exts, oe_link)
1177 OSC_EXTENT_DUMP(level, ext, "reading %d.\n", cnt++);
1178 /* osc_object_unlock(obj); */
1179}
1180
1181/* ------------------ osc extent end ------------------ */
1182
1183static inline int osc_is_ready(struct osc_object *osc)
1184{
1185 return !list_empty(&osc->oo_ready_item) ||
1186 !list_empty(&osc->oo_hp_ready_item);
1187}
1188
1189#define OSC_IO_DEBUG(OSC, STR, args...) \
1190 CDEBUG(D_CACHE, "obj %p ready %d|%c|%c wr %d|%c|%c rd %d|%c " STR, \
1191 (OSC), osc_is_ready(OSC), \
1192 list_empty_marker(&(OSC)->oo_hp_ready_item), \
1193 list_empty_marker(&(OSC)->oo_ready_item), \
1194 atomic_read(&(OSC)->oo_nr_writes), \
1195 list_empty_marker(&(OSC)->oo_hp_exts), \
1196 list_empty_marker(&(OSC)->oo_urgent_exts), \
1197 atomic_read(&(OSC)->oo_nr_reads), \
1198 list_empty_marker(&(OSC)->oo_reading_exts), \
1199 ##args)
1200
1201static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
1202 int cmd)
1203{
1204 struct osc_page *opg = oap2osc_page(oap);
1205 struct cl_page *page = cl_page_top(oap2cl_page(oap));
1206 int result;
1207
1208 LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
1209
1210 ENTRY;
1211 result = cl_page_make_ready(env, page, CRT_WRITE);
1212 if (result == 0)
1213 opg->ops_submit_time = cfs_time_current();
1214 RETURN(result);
1215}
1216
1217static int osc_refresh_count(const struct lu_env *env,
1218 struct osc_async_page *oap, int cmd)
1219{
1220 struct osc_page *opg = oap2osc_page(oap);
1221 struct cl_page *page = oap2cl_page(oap);
1222 struct cl_object *obj;
1223 struct cl_attr *attr = &osc_env_info(env)->oti_attr;
1224
1225 int result;
1226 loff_t kms;
1227
1228 /* readpage queues with _COUNT_STABLE, shouldn't get here. */
1229 LASSERT(!(cmd & OBD_BRW_READ));
1230 LASSERT(opg != NULL);
1231 obj = opg->ops_cl.cpl_obj;
1232
1233 cl_object_attr_lock(obj);
1234 result = cl_object_attr_get(env, obj, attr);
1235 cl_object_attr_unlock(obj);
1236 if (result < 0)
1237 return result;
1238 kms = attr->cat_kms;
1239 if (cl_offset(obj, page->cp_index) >= kms)
1240 /* catch race with truncate */
1241 return 0;
1242 else if (cl_offset(obj, page->cp_index + 1) > kms)
1243 /* catch sub-page write at end of file */
1244 return kms % PAGE_CACHE_SIZE;
1245 else
1246 return PAGE_CACHE_SIZE;
1247}
1248
1249static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
1250 int cmd, int rc)
1251{
1252 struct osc_page *opg = oap2osc_page(oap);
1253 struct cl_page *page = cl_page_top(oap2cl_page(oap));
1254 struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
1255 enum cl_req_type crt;
1256 int srvlock;
1257
1258 ENTRY;
1259
1260 cmd &= ~OBD_BRW_NOQUOTA;
1261 LASSERT(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ));
1262 LASSERT(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE));
1263 LASSERT(opg->ops_transfer_pinned);
1264
1265 /*
1266 * page->cp_req can be NULL if io submission failed before
1267 * cl_req was allocated.
1268 */
1269 if (page->cp_req != NULL)
1270 cl_req_page_done(env, page);
1271 LASSERT(page->cp_req == NULL);
1272
1273 crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
1274 /* Clear opg->ops_transfer_pinned before VM lock is released. */
1275 opg->ops_transfer_pinned = 0;
1276
1277 spin_lock(&obj->oo_seatbelt);
1278 LASSERT(opg->ops_submitter != NULL);
1279 LASSERT(!list_empty(&opg->ops_inflight));
1280 list_del_init(&opg->ops_inflight);
1281 opg->ops_submitter = NULL;
1282 spin_unlock(&obj->oo_seatbelt);
1283
1284 opg->ops_submit_time = 0;
1285 srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
1286
1287 /* statistic */
1288 if (rc == 0 && srvlock) {
1289 struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
1290 struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
1291 int bytes = oap->oap_count;
1292
1293 if (crt == CRT_READ)
1294 stats->os_lockless_reads += bytes;
1295 else
1296 stats->os_lockless_writes += bytes;
1297 }
1298
1299 /*
1300 * This has to be the last operation with the page, as locks are
1301 * released in cl_page_completion() and nothing except for the
1302 * reference counter protects page from concurrent reclaim.
1303 */
1304 lu_ref_del(&page->cp_reference, "transfer", page);
1305
1306 cl_page_completion(env, page, crt, rc);
1307
1308 RETURN(0);
1309}
1310
1311#define OSC_DUMP_GRANT(cli, fmt, args...) do { \
1312 struct client_obd *__tmp = (cli); \
1313 CDEBUG(D_CACHE, "%s: { dirty: %ld/%ld dirty_pages: %d/%d " \
c52f69c5 1314 "dropped: %ld avail: %ld, reserved: %ld, flight: %d } " fmt, \
d7e09d03
PT		 1315 __tmp->cl_import->imp_obd->obd_name, \
1316 __tmp->cl_dirty, __tmp->cl_dirty_max, \
1317 atomic_read(&obd_dirty_pages), obd_max_dirty_pages, \
d7e09d03
PT		 1318 __tmp->cl_lost_grant, __tmp->cl_avail_grant, \
1319 __tmp->cl_reserved_grant, __tmp->cl_w_in_flight, ##args); \
1320} while (0)
1321
1322/* caller must hold loi_list_lock */
1323static void osc_consume_write_grant(struct client_obd *cli,
1324 struct brw_page *pga)
1325{
1326 LASSERT(spin_is_locked(&cli->cl_loi_list_lock.lock));
1327 LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
1328 atomic_inc(&obd_dirty_pages);
1329 cli->cl_dirty += PAGE_CACHE_SIZE;
1330 pga->flag |= OBD_BRW_FROM_GRANT;
1331 CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
1332 PAGE_CACHE_SIZE, pga, pga->pg);
1333 osc_update_next_shrink(cli);
1334}
1335
1336/* the companion to osc_consume_write_grant, called when a brw has completed.
1337 * must be called with the loi lock held. */
1338static void osc_release_write_grant(struct client_obd *cli,
1339 struct brw_page *pga)
1340{
1341 ENTRY;
1342
1343 LASSERT(spin_is_locked(&cli->cl_loi_list_lock.lock));
1344 if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
1345 EXIT;
1346 return;
1347 }
1348
1349 pga->flag &= ~OBD_BRW_FROM_GRANT;
1350 atomic_dec(&obd_dirty_pages);
1351 cli->cl_dirty -= PAGE_CACHE_SIZE;
1352 if (pga->flag & OBD_BRW_NOCACHE) {
1353 pga->flag &= ~OBD_BRW_NOCACHE;
1354 atomic_dec(&obd_dirty_transit_pages);
1355 cli->cl_dirty_transit -= PAGE_CACHE_SIZE;
1356 }
1357 EXIT;
1358}
1359
1360/**
1361 * To avoid sleeping with object lock held, it's good for us allocate enough
1362 * grants before entering into critical section.
1363 *
1364 * client_obd_list_lock held by caller
1365 */
1366static int osc_reserve_grant(struct client_obd *cli, unsigned int bytes)
1367{
1368 int rc = -EDQUOT;
1369
1370 if (cli->cl_avail_grant >= bytes) {
1371 cli->cl_avail_grant -= bytes;
1372 cli->cl_reserved_grant += bytes;
1373 rc = 0;
1374 }
1375 return rc;
1376}
1377
1378static void __osc_unreserve_grant(struct client_obd *cli,
1379 unsigned int reserved, unsigned int unused)
1380{
1381 /* it's quite normal for us to get more grant than reserved.
1382 * Thinking about a case that two extents merged by adding a new
1383 * chunk, we can save one extent tax. If extent tax is greater than
1384 * one chunk, we can save more grant by adding a new chunk */
1385 cli->cl_reserved_grant -= reserved;
1386 if (unused > reserved) {
1387 cli->cl_avail_grant += reserved;
1388 cli->cl_lost_grant += unused - reserved;
1389 } else {
1390 cli->cl_avail_grant += unused;
1391 }
1392}
1393
1394void osc_unreserve_grant(struct client_obd *cli,
1395 unsigned int reserved, unsigned int unused)
1396{
1397 client_obd_list_lock(&cli->cl_loi_list_lock);
1398 __osc_unreserve_grant(cli, reserved, unused);
1399 if (unused > 0)
1400 osc_wake_cache_waiters(cli);
1401 client_obd_list_unlock(&cli->cl_loi_list_lock);
1402}
1403
1404/**
1405 * Free grant after IO is finished or canceled.
1406 *
1407 * @lost_grant is used to remember how many grants we have allocated but not
1408 * used, we should return these grants to OST. There're two cases where grants
1409 * can be lost:
1410 * 1. truncate;
1411 * 2. blocksize at OST is less than PAGE_CACHE_SIZE and a partial page was
1412 * written. In this case OST may use less chunks to serve this partial
1413 * write. OSTs don't actually know the page size on the client side. so
1414 * clients have to calculate lost grant by the blocksize on the OST.
1415 * See filter_grant_check() for details.
1416 */
1417static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
1418 unsigned int lost_grant)
1419{
1420 int grant = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
1421
1422 client_obd_list_lock(&cli->cl_loi_list_lock);
1423 atomic_sub(nr_pages, &obd_dirty_pages);
1424 cli->cl_dirty -= nr_pages << PAGE_CACHE_SHIFT;
1425 cli->cl_lost_grant += lost_grant;
1426 if (cli->cl_avail_grant < grant && cli->cl_lost_grant >= grant) {
1427 /* borrow some grant from truncate to avoid the case that
1428 * truncate uses up all avail grant */
1429 cli->cl_lost_grant -= grant;
1430 cli->cl_avail_grant += grant;
1431 }
1432 osc_wake_cache_waiters(cli);
1433 client_obd_list_unlock(&cli->cl_loi_list_lock);
1434 CDEBUG(D_CACHE, "lost %u grant: %lu avail: %lu dirty: %lu\n",
1435 lost_grant, cli->cl_lost_grant,
1436 cli->cl_avail_grant, cli->cl_dirty);
1437}
1438
1439/**
1440 * The companion to osc_enter_cache(), called when @oap is no longer part of
1441 * the dirty accounting due to error.
1442 */
1443static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap)
1444{
1445 client_obd_list_lock(&cli->cl_loi_list_lock);
1446 osc_release_write_grant(cli, &oap->oap_brw_page);
1447 client_obd_list_unlock(&cli->cl_loi_list_lock);
1448}
1449
1450/**
1451 * Non-blocking version of osc_enter_cache() that consumes grant only when it
1452 * is available.
1453 */
1454static int osc_enter_cache_try(struct client_obd *cli,
1455 struct osc_async_page *oap,
1456 int bytes, int transient)
1457{
1458 int rc;
1459
1460 OSC_DUMP_GRANT(cli, "need:%d.\n", bytes);
1461
1462 rc = osc_reserve_grant(cli, bytes);
1463 if (rc < 0)
1464 return 0;
1465
1466 if (cli->cl_dirty + PAGE_CACHE_SIZE <= cli->cl_dirty_max &&
c52f69c5 1467 atomic_read(&obd_dirty_pages) + 1 <= obd_max_dirty_pages) {
d7e09d03
PT		 1468 osc_consume_write_grant(cli, &oap->oap_brw_page);
1469 if (transient) {
1470 cli->cl_dirty_transit += PAGE_CACHE_SIZE;
1471 atomic_inc(&obd_dirty_transit_pages);
1472 oap->oap_brw_flags |= OBD_BRW_NOCACHE;
1473 }
1474 rc = 1;
1475 } else {
1476 __osc_unreserve_grant(cli, bytes, bytes);
1477 rc = 0;
1478 }
1479 return rc;
1480}
1481
1482static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
1483{
1484 int rc;
1485 client_obd_list_lock(&cli->cl_loi_list_lock);
1486 rc = list_empty(&ocw->ocw_entry);
1487 client_obd_list_unlock(&cli->cl_loi_list_lock);
1488 return rc;
1489}
1490
1491/**
1492 * The main entry to reserve dirty page accounting. Usually the grant reserved
1493 * in this function will be freed in bulk in osc_free_grant() unless it fails
1494 * to add osc cache, in that case, it will be freed in osc_exit_cache().
1495 *
1496 * The process will be put into sleep if it's already run out of grant.
1497 */
1498static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
1499 struct osc_async_page *oap, int bytes)
1500{
1501 struct osc_object *osc = oap->oap_obj;
1502 struct lov_oinfo *loi = osc->oo_oinfo;
1503 struct osc_cache_waiter ocw;
1504 struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
1505 int rc = -EDQUOT;
1506 ENTRY;
1507
1508 OSC_DUMP_GRANT(cli, "need:%d.\n", bytes);
1509
1510 client_obd_list_lock(&cli->cl_loi_list_lock);
1511
1512 /* force the caller to try sync io. this can jump the list
1513 * of queued writes and create a discontiguous rpc stream */
1514 if (OBD_FAIL_CHECK(OBD_FAIL_OSC_NO_GRANT) ||
1515 cli->cl_dirty_max < PAGE_CACHE_SIZE ||
1516 cli->cl_ar.ar_force_sync || loi->loi_ar.ar_force_sync)
1517 GOTO(out, rc = -EDQUOT);
1518
1519 /* Hopefully normal case - cache space and write credits available */
1520 if (osc_enter_cache_try(cli, oap, bytes, 0))
1521 GOTO(out, rc = 0);
1522
1523 /* We can get here for two reasons: too many dirty pages in cache, or
1524 * run out of grants. In both cases we should write dirty pages out.
1525 * Adding a cache waiter will trigger urgent write-out no matter what
1526 * RPC size will be.
1527 * The exiting condition is no avail grants and no dirty pages caching,
1528 * that really means there is no space on the OST. */
1529 init_waitqueue_head(&ocw.ocw_waitq);
1530 ocw.ocw_oap = oap;
1531 ocw.ocw_grant = bytes;
1532 while (cli->cl_dirty > 0 || cli->cl_w_in_flight > 0) {
1533 list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
1534 ocw.ocw_rc = 0;
1535 client_obd_list_unlock(&cli->cl_loi_list_lock);
1536
1537 osc_io_unplug_async(env, cli, NULL);
1538
1539 CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
1540 cli->cl_import->imp_obd->obd_name, &ocw, oap);
1541
1542 rc = l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
1543
1544 client_obd_list_lock(&cli->cl_loi_list_lock);
1545
1546 /* l_wait_event is interrupted by signal */
1547 if (rc < 0) {
1548 list_del_init(&ocw.ocw_entry);
1549 GOTO(out, rc);
1550 }
1551
1552 LASSERT(list_empty(&ocw.ocw_entry));
1553 rc = ocw.ocw_rc;
1554
1555 if (rc != -EDQUOT)
1556 GOTO(out, rc);
1557 if (osc_enter_cache_try(cli, oap, bytes, 0))
1558 GOTO(out, rc = 0);
1559 }
1560 EXIT;
1561out:
1562 client_obd_list_unlock(&cli->cl_loi_list_lock);
1563 OSC_DUMP_GRANT(cli, "returned %d.\n", rc);
1564 RETURN(rc);
1565}
1566
1567/* caller must hold loi_list_lock */
1568void osc_wake_cache_waiters(struct client_obd *cli)
1569{
1570 struct list_head *l, *tmp;
1571 struct osc_cache_waiter *ocw;
1572
1573 ENTRY;
1574 list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
1575 ocw = list_entry(l, struct osc_cache_waiter, ocw_entry);
1576 list_del_init(&ocw->ocw_entry);
1577
1578 ocw->ocw_rc = -EDQUOT;
1579 /* we can't dirty more */
c52f69c5
OD		 1580 if ((cli->cl_dirty + PAGE_CACHE_SIZE > cli->cl_dirty_max) ||
1581 (atomic_read(&obd_dirty_pages) + 1 >
1582 obd_max_dirty_pages)) {
d7e09d03
PT		 1583 CDEBUG(D_CACHE, "no dirty room: dirty: %ld "
1584 "osc max %ld, sys max %d\n", cli->cl_dirty,
1585 cli->cl_dirty_max, obd_max_dirty_pages);
1586 goto wakeup;
1587 }
1588
1589 ocw->ocw_rc = 0;
1590 if (!osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
1591 ocw->ocw_rc = -EDQUOT;
1592
1593wakeup:
1594 CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
1595 ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
1596
1597 wake_up(&ocw->ocw_waitq);
1598 }
1599
1600 EXIT;
1601}
1602
1603static int osc_max_rpc_in_flight(struct client_obd *cli, struct osc_object *osc)
1604{
1605 int hprpc = !!list_empty(&osc->oo_hp_exts);
1606 return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
1607}
1608
1609/* This maintains the lists of pending pages to read/write for a given object
1610 * (lop). This is used by osc_check_rpcs->osc_next_obj() and osc_list_maint()
1611 * to quickly find objects that are ready to send an RPC. */
1612static int osc_makes_rpc(struct client_obd *cli, struct osc_object *osc,
1613 int cmd)
1614{
1615 int invalid_import = 0;
1616 ENTRY;
1617
1618 /* if we have an invalid import we want to drain the queued pages
1619 * by forcing them through rpcs that immediately fail and complete
1620 * the pages. recovery relies on this to empty the queued pages
1621 * before canceling the locks and evicting down the llite pages */
1622 if ((cli->cl_import == NULL || cli->cl_import->imp_invalid))
1623 invalid_import = 1;
1624
1625 if (cmd & OBD_BRW_WRITE) {
1626 if (atomic_read(&osc->oo_nr_writes) == 0)
1627 RETURN(0);
1628 if (invalid_import) {
1629 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1630 RETURN(1);
1631 }
1632 if (!list_empty(&osc->oo_hp_exts)) {
1633 CDEBUG(D_CACHE, "high prio request forcing RPC\n");
1634 RETURN(1);
1635 }
1636 if (!list_empty(&osc->oo_urgent_exts)) {
1637 CDEBUG(D_CACHE, "urgent request forcing RPC\n");
1638 RETURN(1);
1639 }
1640 /* trigger a write rpc stream as long as there are dirtiers
1641 * waiting for space. as they're waiting, they're not going to
1642 * create more pages to coalesce with what's waiting.. */
1643 if (!list_empty(&cli->cl_cache_waiters)) {
1644 CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
1645 RETURN(1);
1646 }
1647 if (atomic_read(&osc->oo_nr_writes) >=
1648 cli->cl_max_pages_per_rpc)
1649 RETURN(1);
1650 } else {
1651 if (atomic_read(&osc->oo_nr_reads) == 0)
1652 RETURN(0);
1653 if (invalid_import) {
1654 CDEBUG(D_CACHE, "invalid import forcing RPC\n");
1655 RETURN(1);
1656 }
1657 /* all read are urgent. */
1658 if (!list_empty(&osc->oo_reading_exts))
1659 RETURN(1);
1660 }
1661
1662 RETURN(0);
1663}
1664
1665static void osc_update_pending(struct osc_object *obj, int cmd, int delta)
1666{
1667 struct client_obd *cli = osc_cli(obj);
1668 if (cmd & OBD_BRW_WRITE) {
1669 atomic_add(delta, &obj->oo_nr_writes);
1670 atomic_add(delta, &cli->cl_pending_w_pages);
1671 LASSERT(atomic_read(&obj->oo_nr_writes) >= 0);
1672 } else {
1673 atomic_add(delta, &obj->oo_nr_reads);
1674 atomic_add(delta, &cli->cl_pending_r_pages);
1675 LASSERT(atomic_read(&obj->oo_nr_reads) >= 0);
1676 }
1677 OSC_IO_DEBUG(obj, "update pending cmd %d delta %d.\n", cmd, delta);
1678}
1679
1680static int osc_makes_hprpc(struct osc_object *obj)
1681{
1682 return !list_empty(&obj->oo_hp_exts);
1683}
1684
1685static void on_list(struct list_head *item, struct list_head *list, int should_be_on)
1686{
1687 if (list_empty(item) && should_be_on)
1688 list_add_tail(item, list);
1689 else if (!list_empty(item) && !should_be_on)
1690 list_del_init(item);
1691}
1692
1693/* maintain the osc's cli list membership invariants so that osc_send_oap_rpc
1694 * can find pages to build into rpcs quickly */
1695static int __osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1696{
1697 if (osc_makes_hprpc(osc)) {
1698 /* HP rpc */
1699 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list, 0);
1700 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
1701 } else {
1702 on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
1703 on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list,
1704 osc_makes_rpc(cli, osc, OBD_BRW_WRITE) ||
1705 osc_makes_rpc(cli, osc, OBD_BRW_READ));
1706 }
1707
1708 on_list(&osc->oo_write_item, &cli->cl_loi_write_list,
1709 atomic_read(&osc->oo_nr_writes) > 0);
1710
1711 on_list(&osc->oo_read_item, &cli->cl_loi_read_list,
1712 atomic_read(&osc->oo_nr_reads) > 0);
1713
1714 return osc_is_ready(osc);
1715}
1716
1717static int osc_list_maint(struct client_obd *cli, struct osc_object *osc)
1718{
1719 int is_ready;
1720
1721 client_obd_list_lock(&cli->cl_loi_list_lock);
1722 is_ready = __osc_list_maint(cli, osc);
1723 client_obd_list_unlock(&cli->cl_loi_list_lock);
1724
1725 return is_ready;
1726}
1727
1728/* this is trying to propogate async writeback errors back up to the
1729 * application. As an async write fails we record the error code for later if
1730 * the app does an fsync. As long as errors persist we force future rpcs to be
1731 * sync so that the app can get a sync error and break the cycle of queueing
1732 * pages for which writeback will fail. */
1733static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
1734 int rc)
1735{
1736 if (rc) {
1737 if (!ar->ar_rc)
1738 ar->ar_rc = rc;
1739
1740 ar->ar_force_sync = 1;
1741 ar->ar_min_xid = ptlrpc_sample_next_xid();
1742 return;
1743
1744 }
1745
1746 if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
1747 ar->ar_force_sync = 0;
1748}
1749
d7e09d03
PT		 1750
1751/* this must be called holding the loi list lock to give coverage to exit_cache,
1752 * async_flag maintenance, and oap_request */
1753static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
1754 struct osc_async_page *oap, int sent, int rc)
1755{
1756 struct osc_object *osc = oap->oap_obj;
1757 struct lov_oinfo *loi = osc->oo_oinfo;
1758 __u64 xid = 0;
1759
1760 ENTRY;
1761 if (oap->oap_request != NULL) {
d7e09d03
PT		 1762 xid = ptlrpc_req_xid(oap->oap_request);
1763 ptlrpc_req_finished(oap->oap_request);
1764 oap->oap_request = NULL;
1765 }
1766
1767 /* As the transfer for this page is being done, clear the flags */
1768 spin_lock(&oap->oap_lock);
1769 oap->oap_async_flags = 0;
1770 spin_unlock(&oap->oap_lock);
1771 oap->oap_interrupted = 0;
1772
1773 if (oap->oap_cmd & OBD_BRW_WRITE && xid > 0) {
1774 client_obd_list_lock(&cli->cl_loi_list_lock);
1775 osc_process_ar(&cli->cl_ar, xid, rc);
1776 osc_process_ar(&loi->loi_ar, xid, rc);
1777 client_obd_list_unlock(&cli->cl_loi_list_lock);
1778 }
1779
1780 rc = osc_completion(env, oap, oap->oap_cmd, rc);
1781 if (rc)
1782 CERROR("completion on oap %p obj %p returns %d.\n",
1783 oap, osc, rc);
1784
1785 EXIT;
1786}
1787
1788/**
1789 * Try to add extent to one RPC. We need to think about the following things:
1790 * - # of pages must not be over max_pages_per_rpc
1791 * - extent must be compatible with previous ones
1792 */
1793static int try_to_add_extent_for_io(struct client_obd *cli,
1794 struct osc_extent *ext, struct list_head *rpclist,
1795 int *pc, unsigned int *max_pages)
1796{
1797 struct osc_extent *tmp;
1798 ENTRY;
1799
1800 EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE),
1801 ext);
1802
1803 *max_pages = max(ext->oe_mppr, *max_pages);
1804 if (*pc + ext->oe_nr_pages > *max_pages)
1805 RETURN(0);
1806
1807 list_for_each_entry(tmp, rpclist, oe_link) {
1808 EASSERT(tmp->oe_owner == current, tmp);
1809#if 0
1810 if (overlapped(tmp, ext)) {
1811 OSC_EXTENT_DUMP(D_ERROR, tmp, "overlapped %p.\n", ext);
1812 EASSERT(0, ext);
1813 }
1814#endif
1815
1816 if (tmp->oe_srvlock != ext->oe_srvlock ||
1817 !tmp->oe_grants != !ext->oe_grants)
1818 RETURN(0);
1819
1820 /* remove break for strict check */
1821 break;
1822 }
1823
1824 *pc += ext->oe_nr_pages;
1825 list_move_tail(&ext->oe_link, rpclist);
1826 ext->oe_owner = current;
1827 RETURN(1);
1828}
1829
1830/**
1831 * In order to prevent multiple ptlrpcd from breaking contiguous extents,
1832 * get_write_extent() takes all appropriate extents in atomic.
1833 *
1834 * The following policy is used to collect extents for IO:
1835 * 1. Add as many HP extents as possible;
1836 * 2. Add the first urgent extent in urgent extent list and take it out of
1837 * urgent list;
1838 * 3. Add subsequent extents of this urgent extent;
1839 * 4. If urgent list is not empty, goto 2;
1840 * 5. Traverse the extent tree from the 1st extent;
1841 * 6. Above steps exit if there is no space in this RPC.
1842 */
1843static int get_write_extents(struct osc_object *obj, struct list_head *rpclist)
1844{
1845 struct client_obd *cli = osc_cli(obj);
1846 struct osc_extent *ext;
1847 int page_count = 0;
1848 unsigned int max_pages = cli->cl_max_pages_per_rpc;
1849
1850 LASSERT(osc_object_is_locked(obj));
1851 while (!list_empty(&obj->oo_hp_exts)) {
1852 ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
1853 oe_link);
1854 LASSERT(ext->oe_state == OES_CACHE);
1855 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1856 &max_pages))
1857 return page_count;
1858 EASSERT(ext->oe_nr_pages <= max_pages, ext);
1859 }
1860 if (page_count == max_pages)
1861 return page_count;
1862
1863 while (!list_empty(&obj->oo_urgent_exts)) {
1864 ext = list_entry(obj->oo_urgent_exts.next,
1865 struct osc_extent, oe_link);
1866 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1867 &max_pages))
1868 return page_count;
1869
1870 if (!ext->oe_intree)
1871 continue;
1872
1873 while ((ext = next_extent(ext)) != NULL) {
1874 if ((ext->oe_state != OES_CACHE) ||
1875 (!list_empty(&ext->oe_link) &&
1876 ext->oe_owner != NULL))
1877 continue;
1878
1879 if (!try_to_add_extent_for_io(cli, ext, rpclist,
1880 &page_count, &max_pages))
1881 return page_count;
1882 }
1883 }
1884 if (page_count == max_pages)
1885 return page_count;
1886
1887 ext = first_extent(obj);
1888 while (ext != NULL) {
1889 if ((ext->oe_state != OES_CACHE) ||
1890 /* this extent may be already in current rpclist */
1891 (!list_empty(&ext->oe_link) && ext->oe_owner != NULL)) {
1892 ext = next_extent(ext);
1893 continue;
1894 }
1895
1896 if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
1897 &max_pages))
1898 return page_count;
1899
1900 ext = next_extent(ext);
1901 }
1902 return page_count;
1903}
1904
1905static int
1906osc_send_write_rpc(const struct lu_env *env, struct client_obd *cli,
1907 struct osc_object *osc, pdl_policy_t pol)
1908{
1909 LIST_HEAD(rpclist);
1910 struct osc_extent *ext;
1911 struct osc_extent *tmp;
1912 struct osc_extent *first = NULL;
1913 obd_count page_count = 0;
1914 int srvlock = 0;
1915 int rc = 0;
1916 ENTRY;
1917
1918 LASSERT(osc_object_is_locked(osc));
1919
1920 page_count = get_write_extents(osc, &rpclist);
1921 LASSERT(equi(page_count == 0, list_empty(&rpclist)));
1922
1923 if (list_empty(&rpclist))
1924 RETURN(0);
1925
1926 osc_update_pending(osc, OBD_BRW_WRITE, -page_count);
1927
1928 list_for_each_entry(ext, &rpclist, oe_link) {
1929 LASSERT(ext->oe_state == OES_CACHE ||
1930 ext->oe_state == OES_LOCK_DONE);
1931 if (ext->oe_state == OES_CACHE)
1932 osc_extent_state_set(ext, OES_LOCKING);
1933 else
1934 osc_extent_state_set(ext, OES_RPC);
1935 }
1936
1937 /* we're going to grab page lock, so release object lock because
1938 * lock order is page lock -> object lock. */
1939 osc_object_unlock(osc);
1940
1941 list_for_each_entry_safe(ext, tmp, &rpclist, oe_link) {
1942 if (ext->oe_state == OES_LOCKING) {
1943 rc = osc_extent_make_ready(env, ext);
1944 if (unlikely(rc < 0)) {
1945 list_del_init(&ext->oe_link);
1946 osc_extent_finish(env, ext, 0, rc);
1947 continue;
1948 }
1949 }
1950 if (first == NULL) {
1951 first = ext;
1952 srvlock = ext->oe_srvlock;
1953 } else {
1954 LASSERT(srvlock == ext->oe_srvlock);
1955 }
1956 }
1957
1958 if (!list_empty(&rpclist)) {
1959 LASSERT(page_count > 0);
1960 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_WRITE, pol);
1961 LASSERT(list_empty(&rpclist));
1962 }
1963
1964 osc_object_lock(osc);
1965 RETURN(rc);
1966}
1967
1968/**
1969 * prepare pages for ASYNC io and put pages in send queue.
1970 *
1971 * \param cmd OBD_BRW_* macroses
1972 * \param lop pending pages
1973 *
1974 * \return zero if no page added to send queue.
1975 * \return 1 if pages successfully added to send queue.
1976 * \return negative on errors.
1977 */
1978static int
1979osc_send_read_rpc(const struct lu_env *env, struct client_obd *cli,
1980 struct osc_object *osc, pdl_policy_t pol)
1981{
1982 struct osc_extent *ext;
1983 struct osc_extent *next;
1984 LIST_HEAD(rpclist);
1985 int page_count = 0;
1986 unsigned int max_pages = cli->cl_max_pages_per_rpc;
1987 int rc = 0;
1988 ENTRY;
1989
1990 LASSERT(osc_object_is_locked(osc));
1991 list_for_each_entry_safe(ext, next,
1992 &osc->oo_reading_exts, oe_link) {
1993 EASSERT(ext->oe_state == OES_LOCK_DONE, ext);
1994 if (!try_to_add_extent_for_io(cli, ext, &rpclist, &page_count,
1995 &max_pages))
1996 break;
1997 osc_extent_state_set(ext, OES_RPC);
1998 EASSERT(ext->oe_nr_pages <= max_pages, ext);
1999 }
2000 LASSERT(page_count <= max_pages);
2001
2002 osc_update_pending(osc, OBD_BRW_READ, -page_count);
2003
2004 if (!list_empty(&rpclist)) {
2005 osc_object_unlock(osc);
2006
2007 LASSERT(page_count > 0);
2008 rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_READ, pol);
2009 LASSERT(list_empty(&rpclist));
2010
2011 osc_object_lock(osc);
2012 }
2013 RETURN(rc);
2014}
2015
2016#define list_to_obj(list, item) ({ \
2017 struct list_head *__tmp = (list)->next; \
2018 list_del_init(__tmp); \
2019 list_entry(__tmp, struct osc_object, oo_##item); \
2020})
2021
2022/* This is called by osc_check_rpcs() to find which objects have pages that
2023 * we could be sending. These lists are maintained by osc_makes_rpc(). */
2024static struct osc_object *osc_next_obj(struct client_obd *cli)
2025{
2026 ENTRY;
2027
2028 /* First return objects that have blocked locks so that they
2029 * will be flushed quickly and other clients can get the lock,
2030 * then objects which have pages ready to be stuffed into RPCs */
2031 if (!list_empty(&cli->cl_loi_hp_ready_list))
2032 RETURN(list_to_obj(&cli->cl_loi_hp_ready_list, hp_ready_item));
2033 if (!list_empty(&cli->cl_loi_ready_list))
2034 RETURN(list_to_obj(&cli->cl_loi_ready_list, ready_item));
2035
2036 /* then if we have cache waiters, return all objects with queued
2037 * writes. This is especially important when many small files
2038 * have filled up the cache and not been fired into rpcs because
2039 * they don't pass the nr_pending/object threshhold */
2040 if (!list_empty(&cli->cl_cache_waiters) &&
2041 !list_empty(&cli->cl_loi_write_list))
2042 RETURN(list_to_obj(&cli->cl_loi_write_list, write_item));
2043
2044 /* then return all queued objects when we have an invalid import
2045 * so that they get flushed */
2046 if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
2047 if (!list_empty(&cli->cl_loi_write_list))
2048 RETURN(list_to_obj(&cli->cl_loi_write_list,
2049 write_item));
2050 if (!list_empty(&cli->cl_loi_read_list))
2051 RETURN(list_to_obj(&cli->cl_loi_read_list,
2052 read_item));
2053 }
2054 RETURN(NULL);
2055}
2056
2057/* called with the loi list lock held */
2058static void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli,
2059 pdl_policy_t pol)
2060{
2061 struct osc_object *osc;
2062 int rc = 0;
2063 ENTRY;
2064
2065 while ((osc = osc_next_obj(cli)) != NULL) {
2066 struct cl_object *obj = osc2cl(osc);
2067 struct lu_ref_link *link;
2068
2069 OSC_IO_DEBUG(osc, "%lu in flight\n", rpcs_in_flight(cli));
2070
2071 if (osc_max_rpc_in_flight(cli, osc)) {
2072 __osc_list_maint(cli, osc);
2073 break;
2074 }
2075
2076 cl_object_get(obj);
2077 client_obd_list_unlock(&cli->cl_loi_list_lock);
2078 link = lu_object_ref_add(&obj->co_lu, "check", current);
2079
2080 /* attempt some read/write balancing by alternating between
2081 * reads and writes in an object. The makes_rpc checks here
2082 * would be redundant if we were getting read/write work items
2083 * instead of objects. we don't want send_oap_rpc to drain a
2084 * partial read pending queue when we're given this object to
2085 * do io on writes while there are cache waiters */
2086 osc_object_lock(osc);
2087 if (osc_makes_rpc(cli, osc, OBD_BRW_WRITE)) {
2088 rc = osc_send_write_rpc(env, cli, osc, pol);
2089 if (rc < 0) {
2090 CERROR("Write request failed with %d\n", rc);
2091
2092 /* osc_send_write_rpc failed, mostly because of
2093 * memory pressure.
2094 *
2095 * It can't break here, because if:
2096 * - a page was submitted by osc_io_submit, so
2097 * page locked;
2098 * - no request in flight
2099 * - no subsequent request
2100 * The system will be in live-lock state,
2101 * because there is no chance to call
2102 * osc_io_unplug() and osc_check_rpcs() any
2103 * more. pdflush can't help in this case,
2104 * because it might be blocked at grabbing
2105 * the page lock as we mentioned.
2106 *
2107 * Anyway, continue to drain pages. */
2108 /* break; */
2109 }
2110 }
2111 if (osc_makes_rpc(cli, osc, OBD_BRW_READ)) {
2112 rc = osc_send_read_rpc(env, cli, osc, pol);
2113 if (rc < 0)
2114 CERROR("Read request failed with %d\n", rc);
2115 }
2116 osc_object_unlock(osc);
2117
2118 osc_list_maint(cli, osc);
2119 lu_object_ref_del_at(&obj->co_lu, link, "check", current);
2120 cl_object_put(env, obj);
2121
2122 client_obd_list_lock(&cli->cl_loi_list_lock);
2123 }
2124}
2125
2126static int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
2127 struct osc_object *osc, pdl_policy_t pol, int async)
2128{
d7e09d03
PT		 2129 int rc = 0;
2130
cad6fafa
BJ		 2131 if (osc != NULL && osc_list_maint(cli, osc) == 0)
2132 return 0;
2133
2134 if (!async) {
2135 /* disable osc_lru_shrink() temporarily to avoid
2136 * potential stack overrun problem. LU-2859 */
2137 atomic_inc(&cli->cl_lru_shrinkers);
2138 client_obd_list_lock(&cli->cl_loi_list_lock);
2139 osc_check_rpcs(env, cli, pol);
2140 client_obd_list_unlock(&cli->cl_loi_list_lock);
2141 atomic_dec(&cli->cl_lru_shrinkers);
2142 } else {
2143 CDEBUG(D_CACHE, "Queue writeback work for client %p.\n", cli);
2144 LASSERT(cli->cl_writeback_work != NULL);
2145 rc = ptlrpcd_queue_work(cli->cl_writeback_work);
d7e09d03 2146 }
d7e09d03
PT		 2147 return rc;
2148}
2149
2150static int osc_io_unplug_async(const struct lu_env *env,
2151 struct client_obd *cli, struct osc_object *osc)
2152{
2153 /* XXX: policy is no use actually. */
2154 return osc_io_unplug0(env, cli, osc, PDL_POLICY_ROUND, 1);
2155}
2156
2157void osc_io_unplug(const struct lu_env *env, struct client_obd *cli,
2158 struct osc_object *osc, pdl_policy_t pol)
2159{
2160 (void)osc_io_unplug0(env, cli, osc, pol, 0);
2161}
2162
2163int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
2164 struct page *page, loff_t offset)
2165{
2166 struct obd_export *exp = osc_export(osc);
2167 struct osc_async_page *oap = &ops->ops_oap;
2168 ENTRY;
2169
2170 if (!page)
2171 return cfs_size_round(sizeof(*oap));
2172
2173 oap->oap_magic = OAP_MAGIC;
2174 oap->oap_cli = &exp->exp_obd->u.cli;
2175 oap->oap_obj = osc;
2176
2177 oap->oap_page = page;
2178 oap->oap_obj_off = offset;
2179 LASSERT(!(offset & ~CFS_PAGE_MASK));
2180
2181 if (!client_is_remote(exp) && cfs_capable(CFS_CAP_SYS_RESOURCE))
2182 oap->oap_brw_flags = OBD_BRW_NOQUOTA;
2183
2184 INIT_LIST_HEAD(&oap->oap_pending_item);
2185 INIT_LIST_HEAD(&oap->oap_rpc_item);
2186
2187 spin_lock_init(&oap->oap_lock);
2188 CDEBUG(D_INFO, "oap %p page %p obj off "LPU64"\n",
2189 oap, page, oap->oap_obj_off);
2190 RETURN(0);
2191}
2192
2193int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
2194 struct osc_page *ops)
2195{
2196 struct osc_io *oio = osc_env_io(env);
2197 struct osc_extent *ext = NULL;
2198 struct osc_async_page *oap = &ops->ops_oap;
2199 struct client_obd *cli = oap->oap_cli;
2200 struct osc_object *osc = oap->oap_obj;
2201 pgoff_t index;
2202 int grants = 0;
2203 int brw_flags = OBD_BRW_ASYNC;
2204 int cmd = OBD_BRW_WRITE;
2205 int need_release = 0;
2206 int rc = 0;
2207 ENTRY;
2208
2209 if (oap->oap_magic != OAP_MAGIC)
2210 RETURN(-EINVAL);
2211
2212 if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
2213 RETURN(-EIO);
2214
2215 if (!list_empty(&oap->oap_pending_item) ||
2216 !list_empty(&oap->oap_rpc_item))
2217 RETURN(-EBUSY);
2218
2219 /* Set the OBD_BRW_SRVLOCK before the page is queued. */
2220 brw_flags |= ops->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
2221 if (!client_is_remote(osc_export(osc)) &&
2222 cfs_capable(CFS_CAP_SYS_RESOURCE)) {
2223 brw_flags |= OBD_BRW_NOQUOTA;
2224 cmd |= OBD_BRW_NOQUOTA;
2225 }
2226
2227 /* check if the file's owner/group is over quota */
2228 if (!(cmd & OBD_BRW_NOQUOTA)) {
2229 struct cl_object *obj;
2230 struct cl_attr *attr;
2231 unsigned int qid[MAXQUOTAS];
2232
2233 obj = cl_object_top(&osc->oo_cl);
2234 attr = &osc_env_info(env)->oti_attr;
2235
2236 cl_object_attr_lock(obj);
2237 rc = cl_object_attr_get(env, obj, attr);
2238 cl_object_attr_unlock(obj);
2239
2240 qid[USRQUOTA] = attr->cat_uid;
2241 qid[GRPQUOTA] = attr->cat_gid;
2242 if (rc == 0 && osc_quota_chkdq(cli, qid) == NO_QUOTA)
2243 rc = -EDQUOT;
2244 if (rc)
2245 RETURN(rc);
2246 }
2247
2248 oap->oap_cmd = cmd;
2249 oap->oap_page_off = ops->ops_from;
2250 oap->oap_count = ops->ops_to - ops->ops_from;
2251 oap->oap_async_flags = 0;
2252 oap->oap_brw_flags = brw_flags;
2253
2254 OSC_IO_DEBUG(osc, "oap %p page %p added for cmd %d\n",
2255 oap, oap->oap_page, oap->oap_cmd & OBD_BRW_RWMASK);
2256
2257 index = oap2cl_page(oap)->cp_index;
2258
2259 /* Add this page into extent by the following steps:
2260 * 1. if there exists an active extent for this IO, mostly this page
2261 * can be added to the active extent and sometimes we need to
2262 * expand extent to accomodate this page;
2263 * 2. otherwise, a new extent will be allocated. */
2264
2265 ext = oio->oi_active;
2266 if (ext != NULL && ext->oe_start <= index && ext->oe_max_end >= index) {
2267 /* one chunk plus extent overhead must be enough to write this
2268 * page */
2269 grants = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
2270 if (ext->oe_end >= index)
2271 grants = 0;
2272
2273 /* it doesn't need any grant to dirty this page */
2274 client_obd_list_lock(&cli->cl_loi_list_lock);
2275 rc = osc_enter_cache_try(cli, oap, grants, 0);
2276 client_obd_list_unlock(&cli->cl_loi_list_lock);
2277 if (rc == 0) { /* try failed */
2278 grants = 0;
2279 need_release = 1;
2280 } else if (ext->oe_end < index) {
2281 int tmp = grants;
2282 /* try to expand this extent */
2283 rc = osc_extent_expand(ext, index, &tmp);
2284 if (rc < 0) {
2285 need_release = 1;
2286 /* don't free reserved grant */
2287 } else {
2288 OSC_EXTENT_DUMP(D_CACHE, ext,
2289 "expanded for %lu.\n", index);
2290 osc_unreserve_grant(cli, grants, tmp);
2291 grants = 0;
2292 }
2293 }
2294 rc = 0;
2295 } else if (ext != NULL) {
2296 /* index is located outside of active extent */
2297 need_release = 1;
2298 }
2299 if (need_release) {
2300 osc_extent_release(env, ext);
2301 oio->oi_active = NULL;
2302 ext = NULL;
2303 }
2304
2305 if (ext == NULL) {
2306 int tmp = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
2307
2308 /* try to find new extent to cover this page */
2309 LASSERT(oio->oi_active == NULL);
2310 /* we may have allocated grant for this page if we failed
2311 * to expand the previous active extent. */
2312 LASSERT(ergo(grants > 0, grants >= tmp));
2313
2314 rc = 0;
2315 if (grants == 0) {
2316 /* we haven't allocated grant for this page. */
2317 rc = osc_enter_cache(env, cli, oap, tmp);
2318 if (rc == 0)
2319 grants = tmp;
2320 }
2321
2322 tmp = grants;
2323 if (rc == 0) {
2324 ext = osc_extent_find(env, osc, index, &tmp);
2325 if (IS_ERR(ext)) {
2326 LASSERT(tmp == grants);
2327 osc_exit_cache(cli, oap);
2328 rc = PTR_ERR(ext);
2329 ext = NULL;
2330 } else {
2331 oio->oi_active = ext;
2332 }
2333 }
2334 if (grants > 0)
2335 osc_unreserve_grant(cli, grants, tmp);
2336 }
2337
2338 LASSERT(ergo(rc == 0, ext != NULL));
2339 if (ext != NULL) {
2340 EASSERTF(ext->oe_end >= index && ext->oe_start <= index,
2341 ext, "index = %lu.\n", index);
2342 LASSERT((oap->oap_brw_flags & OBD_BRW_FROM_GRANT) != 0);
2343
2344 osc_object_lock(osc);
2345 if (ext->oe_nr_pages == 0)
2346 ext->oe_srvlock = ops->ops_srvlock;
2347 else
2348 LASSERT(ext->oe_srvlock == ops->ops_srvlock);
2349 ++ext->oe_nr_pages;
2350 list_add_tail(&oap->oap_pending_item, &ext->oe_pages);
2351 osc_object_unlock(osc);
2352 }
2353 RETURN(rc);
2354}
2355
2356int osc_teardown_async_page(const struct lu_env *env,
2357 struct osc_object *obj, struct osc_page *ops)
2358{
2359 struct osc_async_page *oap = &ops->ops_oap;
2360 struct osc_extent *ext = NULL;
2361 int rc = 0;
2362 ENTRY;
2363
2364 LASSERT(oap->oap_magic == OAP_MAGIC);
2365
2366 CDEBUG(D_INFO, "teardown oap %p page %p at index %lu.\n",
2367 oap, ops, oap2cl_page(oap)->cp_index);
2368
2369 osc_object_lock(obj);
2370 if (!list_empty(&oap->oap_rpc_item)) {
2371 CDEBUG(D_CACHE, "oap %p is not in cache.\n", oap);
2372 rc = -EBUSY;
2373 } else if (!list_empty(&oap->oap_pending_item)) {
2374 ext = osc_extent_lookup(obj, oap2cl_page(oap)->cp_index);
2375 /* only truncated pages are allowed to be taken out.
2376 * See osc_extent_truncate() and osc_cache_truncate_start()
2377 * for details. */
2378 if (ext != NULL && ext->oe_state != OES_TRUNC) {
2379 OSC_EXTENT_DUMP(D_ERROR, ext, "trunc at %lu.\n",
2380 oap2cl_page(oap)->cp_index);
2381 rc = -EBUSY;
2382 }
2383 }
2384 osc_object_unlock(obj);
2385 if (ext != NULL)
2386 osc_extent_put(env, ext);
2387 RETURN(rc);
2388}
2389
2390/**
2391 * This is called when a page is picked up by kernel to write out.
2392 *
2393 * We should find out the corresponding extent and add the whole extent
2394 * into urgent list. The extent may be being truncated or used, handle it
2395 * carefully.
2396 */
2397int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
2398 struct osc_page *ops)
2399{
2400 struct osc_extent *ext = NULL;
2401 struct osc_object *obj = cl2osc(ops->ops_cl.cpl_obj);
2402 struct cl_page *cp = ops->ops_cl.cpl_page;
2403 pgoff_t index = cp->cp_index;
2404 struct osc_async_page *oap = &ops->ops_oap;
2405 bool unplug = false;
2406 int rc = 0;
2407 ENTRY;
2408
2409 osc_object_lock(obj);
2410 ext = osc_extent_lookup(obj, index);
2411 if (ext == NULL) {
2412 osc_extent_tree_dump(D_ERROR, obj);
2413 LASSERTF(0, "page index %lu is NOT covered.\n", index);
2414 }
2415
2416 switch (ext->oe_state) {
2417 case OES_RPC:
2418 case OES_LOCK_DONE:
2419 CL_PAGE_DEBUG(D_ERROR, env, cl_page_top(cp),
2420 "flush an in-rpc page?\n");
2421 LASSERT(0);
2422 break;
2423 case OES_LOCKING:
2424 /* If we know this extent is being written out, we should abort
2425 * so that the writer can make this page ready. Otherwise, there
2426 * exists a deadlock problem because other process can wait for
2427 * page writeback bit holding page lock; and meanwhile in
2428 * vvp_page_make_ready(), we need to grab page lock before
2429 * really sending the RPC. */
2430 case OES_TRUNC:
2431 /* race with truncate, page will be redirtied */
2432 GOTO(out, rc = -EAGAIN);
2433 default:
2434 break;
2435 }
2436
2437 rc = cl_page_prep(env, io, cl_page_top(cp), CRT_WRITE);
2438 if (rc)
2439 GOTO(out, rc);
2440
2441 spin_lock(&oap->oap_lock);
2442 oap->oap_async_flags |= ASYNC_READY|ASYNC_URGENT;
2443 spin_unlock(&oap->oap_lock);
2444
2445 if (memory_pressure_get())
2446 ext->oe_memalloc = 1;
2447
2448 ext->oe_urgent = 1;
2449 if (ext->oe_state == OES_CACHE) {
2450 OSC_EXTENT_DUMP(D_CACHE, ext,
2451 "flush page %p make it urgent.\n", oap);
2452 if (list_empty(&ext->oe_link))
2453 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2454 unplug = true;
2455 }
2456 rc = 0;
2457 EXIT;
2458
2459out:
2460 osc_object_unlock(obj);
2461 osc_extent_put(env, ext);
2462 if (unplug)
2463 osc_io_unplug_async(env, osc_cli(obj), obj);
2464 return rc;
2465}
2466
2467/**
2468 * this is called when a sync waiter receives an interruption. Its job is to
2469 * get the caller woken as soon as possible. If its page hasn't been put in an
2470 * rpc yet it can dequeue immediately. Otherwise it has to mark the rpc as
2471 * desiring interruption which will forcefully complete the rpc once the rpc
2472 * has timed out.
2473 */
2474int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops)
2475{
2476 struct osc_async_page *oap = &ops->ops_oap;
2477 struct osc_object *obj = oap->oap_obj;
2478 struct client_obd *cli = osc_cli(obj);
2479 struct osc_extent *ext;
2480 struct osc_extent *found = NULL;
2481 struct list_head *plist;
2482 pgoff_t index = oap2cl_page(oap)->cp_index;
2483 int rc = -EBUSY;
2484 int cmd;
2485 ENTRY;
2486
2487 LASSERT(!oap->oap_interrupted);
2488 oap->oap_interrupted = 1;
2489
2490 /* Find out the caching extent */
2491 osc_object_lock(obj);
2492 if (oap->oap_cmd & OBD_BRW_WRITE) {
2493 plist = &obj->oo_urgent_exts;
2494 cmd = OBD_BRW_WRITE;
2495 } else {
2496 plist = &obj->oo_reading_exts;
2497 cmd = OBD_BRW_READ;
2498 }
2499 list_for_each_entry(ext, plist, oe_link) {
2500 if (ext->oe_start <= index && ext->oe_end >= index) {
2501 LASSERT(ext->oe_state == OES_LOCK_DONE);
2502 /* For OES_LOCK_DONE state extent, it has already held
2503 * a refcount for RPC. */
2504 found = osc_extent_get(ext);
2505 break;
2506 }
2507 }
2508 if (found != NULL) {
2509 list_del_init(&found->oe_link);
2510 osc_update_pending(obj, cmd, -found->oe_nr_pages);
2511 osc_object_unlock(obj);
2512
2513 osc_extent_finish(env, found, 0, -EINTR);
2514 osc_extent_put(env, found);
2515 rc = 0;
2516 } else {
2517 osc_object_unlock(obj);
2518 /* ok, it's been put in an rpc. only one oap gets a request
2519 * reference */
2520 if (oap->oap_request != NULL) {
2521 ptlrpc_mark_interrupted(oap->oap_request);
2522 ptlrpcd_wake(oap->oap_request);
2523 ptlrpc_req_finished(oap->oap_request);
2524 oap->oap_request = NULL;
2525 }
2526 }
2527
2528 osc_list_maint(cli, obj);
2529 RETURN(rc);
2530}
2531
2532int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
2533 struct list_head *list, int cmd, int brw_flags)
2534{
2535 struct client_obd *cli = osc_cli(obj);
2536 struct osc_extent *ext;
f13ab92e 2537 struct osc_async_page *oap, *tmp;
d7e09d03
PT		 2538 int page_count = 0;
2539 int mppr = cli->cl_max_pages_per_rpc;
2540 pgoff_t start = CL_PAGE_EOF;
2541 pgoff_t end = 0;
2542 ENTRY;
2543
2544 list_for_each_entry(oap, list, oap_pending_item) {
2545 struct cl_page *cp = oap2cl_page(oap);
2546 if (cp->cp_index > end)
2547 end = cp->cp_index;
2548 if (cp->cp_index < start)
2549 start = cp->cp_index;
2550 ++page_count;
2551 mppr <<= (page_count > mppr);
2552 }
2553
2554 ext = osc_extent_alloc(obj);
2555 if (ext == NULL) {
f13ab92e 2556 list_for_each_entry_safe(oap, tmp, list, oap_pending_item) {
d7e09d03
PT		 2557 list_del_init(&oap->oap_pending_item);
2558 osc_ap_completion(env, cli, oap, 0, -ENOMEM);
2559 }
2560 RETURN(-ENOMEM);
2561 }
2562
2563 ext->oe_rw = !!(cmd & OBD_BRW_READ);
2564 ext->oe_urgent = 1;
2565 ext->oe_start = start;
2566 ext->oe_end = ext->oe_max_end = end;
2567 ext->oe_obj = obj;
2568 ext->oe_srvlock = !!(brw_flags & OBD_BRW_SRVLOCK);
2569 ext->oe_nr_pages = page_count;
2570 ext->oe_mppr = mppr;
2571 list_splice_init(list, &ext->oe_pages);
2572
2573 osc_object_lock(obj);
2574 /* Reuse the initial refcount for RPC, don't drop it */
2575 osc_extent_state_set(ext, OES_LOCK_DONE);
2576 if (cmd & OBD_BRW_WRITE) {
2577 list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
2578 osc_update_pending(obj, OBD_BRW_WRITE, page_count);
2579 } else {
2580 list_add_tail(&ext->oe_link, &obj->oo_reading_exts);
2581 osc_update_pending(obj, OBD_BRW_READ, page_count);
2582 }
2583 osc_object_unlock(obj);
2584
2585 osc_io_unplug(env, cli, obj, PDL_POLICY_ROUND);
2586 RETURN(0);
2587}
2588
2589/**
2590 * Called by osc_io_setattr_start() to freeze and destroy covering extents.
2591 */
2592int osc_cache_truncate_start(const struct lu_env *env, struct osc_io *oio,
2593 struct osc_object *obj, __u64 size)
2594{
2595 struct client_obd *cli = osc_cli(obj);
2596 struct osc_extent *ext;
2597 struct osc_extent *waiting = NULL;
2598 pgoff_t index;
2599 LIST_HEAD(list);
2600 int result = 0;
2601 bool partial;
2602 ENTRY;
2603
2604 /* pages with index greater or equal to index will be truncated. */
2605 index = cl_index(osc2cl(obj), size);
2606 partial = size > cl_offset(osc2cl(obj), index);
2607
2608again:
2609 osc_object_lock(obj);
2610 ext = osc_extent_search(obj, index);
2611 if (ext == NULL)
2612 ext = first_extent(obj);
2613 else if (ext->oe_end < index)
2614 ext = next_extent(ext);
2615 while (ext != NULL) {
2616 EASSERT(ext->oe_state != OES_TRUNC, ext);
2617
2618 if (ext->oe_state > OES_CACHE || ext->oe_urgent) {
2619 /* if ext is in urgent state, it means there must exist
2620 * a page already having been flushed by write_page().
2621 * We have to wait for this extent because we can't
2622 * truncate that page. */
2623 LASSERT(!ext->oe_hp);
2624 OSC_EXTENT_DUMP(D_CACHE, ext,
2625 "waiting for busy extent\n");
2626 waiting = osc_extent_get(ext);
2627 break;
2628 }
2629
2630 OSC_EXTENT_DUMP(D_CACHE, ext, "try to trunc:"LPU64".\n", size);
2631
2632 osc_extent_get(ext);
2633 if (ext->oe_state == OES_ACTIVE) {
2634 /* though we grab inode mutex for write path, but we
2635 * release it before releasing extent(in osc_io_end()),
2636 * so there is a race window that an extent is still
2637 * in OES_ACTIVE when truncate starts. */
2638 LASSERT(!ext->oe_trunc_pending);
2639 ext->oe_trunc_pending = 1;
2640 } else {
2641 EASSERT(ext->oe_state == OES_CACHE, ext);
2642 osc_extent_state_set(ext, OES_TRUNC);
2643 osc_update_pending(obj, OBD_BRW_WRITE,
2644 -ext->oe_nr_pages);
2645 }
2646 EASSERT(list_empty(&ext->oe_link), ext);
2647 list_add_tail(&ext->oe_link, &list);
2648
2649 ext = next_extent(ext);
2650 }
2651 osc_object_unlock(obj);
2652
2653 osc_list_maint(cli, obj);
2654
2655 while (!list_empty(&list)) {
2656 int rc;
2657
2658 ext = list_entry(list.next, struct osc_extent, oe_link);
2659 list_del_init(&ext->oe_link);
2660
2661 /* extent may be in OES_ACTIVE state because inode mutex
2662 * is released before osc_io_end() in file write case */
2663 if (ext->oe_state != OES_TRUNC)
2664 osc_extent_wait(env, ext, OES_TRUNC);
2665
2666 rc = osc_extent_truncate(ext, index, partial);
2667 if (rc < 0) {
2668 if (result == 0)
2669 result = rc;
2670
2671 OSC_EXTENT_DUMP(D_ERROR, ext,
2672 "truncate error %d\n", rc);
2673 } else if (ext->oe_nr_pages == 0) {
2674 osc_extent_remove(ext);
2675 } else {
2676 /* this must be an overlapped extent which means only
2677 * part of pages in this extent have been truncated.
2678 */
2679 EASSERTF(ext->oe_start <= index, ext,
2680 "trunc index = %lu/%d.\n", index, partial);
2681 /* fix index to skip this partially truncated extent */
2682 index = ext->oe_end + 1;
2683 partial = false;
2684
2685 /* we need to hold this extent in OES_TRUNC state so
2686 * that no writeback will happen. This is to avoid
2687 * BUG 17397. */
2688 LASSERT(oio->oi_trunc == NULL);
2689 oio->oi_trunc = osc_extent_get(ext);
2690 OSC_EXTENT_DUMP(D_CACHE, ext,
2691 "trunc at "LPU64"\n", size);
2692 }
2693 osc_extent_put(env, ext);
2694 }
2695 if (waiting != NULL) {
2696 int rc;
2697
2698 /* ignore the result of osc_extent_wait the write initiator
2699 * should take care of it. */
2700 rc = osc_extent_wait(env, waiting, OES_INV);
2701 if (rc < 0)
451721cc 2702 OSC_EXTENT_DUMP(D_CACHE, waiting, "error: %d.\n", rc);
d7e09d03
PT		 2703
2704 osc_extent_put(env, waiting);
2705 waiting = NULL;
2706 goto again;
2707 }
2708 RETURN(result);
2709}
2710
2711/**
2712 * Called after osc_io_setattr_end to add oio->oi_trunc back to cache.
2713 */
2714void osc_cache_truncate_end(const struct lu_env *env, struct osc_io *oio,
2715 struct osc_object *obj)
2716{
2717 struct osc_extent *ext = oio->oi_trunc;
2718
2719 oio->oi_trunc = NULL;
2720 if (ext != NULL) {
2721 bool unplug = false;
2722
2723 EASSERT(ext->oe_nr_pages > 0, ext);
2724 EASSERT(ext->oe_state == OES_TRUNC, ext);
2725 EASSERT(!ext->oe_urgent, ext);
2726
2727 OSC_EXTENT_DUMP(D_CACHE, ext, "trunc -> cache.\n");
2728 osc_object_lock(obj);
2729 osc_extent_state_set(ext, OES_CACHE);
2730 if (ext->oe_fsync_wait && !ext->oe_urgent) {
2731 ext->oe_urgent = 1;
2732 list_move_tail(&ext->oe_link, &obj->oo_urgent_exts);
2733 unplug = true;
2734 }
2735 osc_update_pending(obj, OBD_BRW_WRITE, ext->oe_nr_pages);
2736 osc_object_unlock(obj);
2737 osc_extent_put(env, ext);
2738
2739 if (unplug)
2740 osc_io_unplug_async(env, osc_cli(obj), obj);
2741 }
2742}
2743
2744/**
2745 * Wait for extents in a specific range to be written out.
2746 * The caller must have called osc_cache_writeback_range() to issue IO
2747 * otherwise it will take a long time for this function to finish.
2748 *
2749 * Caller must hold inode_mutex , or cancel exclusive dlm lock so that
2750 * nobody else can dirty this range of file while we're waiting for
2751 * extents to be written.
2752 */
2753int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
2754 pgoff_t start, pgoff_t end)
2755{
2756 struct osc_extent *ext;
2757 pgoff_t index = start;
2758 int result = 0;
2759 ENTRY;
2760
2761again:
2762 osc_object_lock(obj);
2763 ext = osc_extent_search(obj, index);
2764 if (ext == NULL)
2765 ext = first_extent(obj);
2766 else if (ext->oe_end < index)
2767 ext = next_extent(ext);
2768 while (ext != NULL) {
2769 int rc;
2770
2771 if (ext->oe_start > end)
2772 break;
2773
2774 if (!ext->oe_fsync_wait) {
2775 ext = next_extent(ext);
2776 continue;
2777 }
2778
2779 EASSERT(ergo(ext->oe_state == OES_CACHE,
2780 ext->oe_hp || ext->oe_urgent), ext);
2781 EASSERT(ergo(ext->oe_state == OES_ACTIVE,
2782 !ext->oe_hp && ext->oe_urgent), ext);
2783
2784 index = ext->oe_end + 1;
2785 osc_extent_get(ext);
2786 osc_object_unlock(obj);
2787
2788 rc = osc_extent_wait(env, ext, OES_INV);
2789 if (result == 0)
2790 result = rc;
2791 osc_extent_put(env, ext);
2792 goto again;
2793 }
2794 osc_object_unlock(obj);
2795
2796 OSC_IO_DEBUG(obj, "sync file range.\n");
2797 RETURN(result);
2798}
2799
2800/**
2801 * Called to write out a range of osc object.
2802 *
2803 * @hp : should be set this is caused by lock cancel;
2804 * @discard: is set if dirty pages should be dropped - file will be deleted or
2805 * truncated, this implies there is no partially discarding extents.
2806 *
2807 * Return how many pages will be issued, or error code if error occurred.
2808 */
2809int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
2810 pgoff_t start, pgoff_t end, int hp, int discard)
2811{
2812 struct osc_extent *ext;
2813 LIST_HEAD(discard_list);
2814 bool unplug = false;
2815 int result = 0;
2816 ENTRY;
2817
2818 osc_object_lock(obj);
2819 ext = osc_extent_search(obj, start);
2820 if (ext == NULL)
2821 ext = first_extent(obj);
2822 else if (ext->oe_end < start)
2823 ext = next_extent(ext);
2824 while (ext != NULL) {
2825 if (ext->oe_start > end)
2826 break;
2827
2828 ext->oe_fsync_wait = 1;
2829 switch (ext->oe_state) {
2830 case OES_CACHE:
2831 result += ext->oe_nr_pages;
2832 if (!discard) {
2833 struct list_head *list = NULL;
2834 if (hp) {
2835 EASSERT(!ext->oe_hp, ext);
2836 ext->oe_hp = 1;
2837 list = &obj->oo_hp_exts;
2838 } else if (!ext->oe_urgent) {
2839 ext->oe_urgent = 1;
2840 list = &obj->oo_urgent_exts;
2841 }
2842 if (list != NULL)
2843 list_move_tail(&ext->oe_link, list);
2844 unplug = true;
2845 } else {
2846 /* the only discarder is lock cancelling, so
2847 * [start, end] must contain this extent */
2848 EASSERT(ext->oe_start >= start &&
2849 ext->oe_max_end <= end, ext);
2850 osc_extent_state_set(ext, OES_LOCKING);
2851 ext->oe_owner = current;
2852 list_move_tail(&ext->oe_link,
2853 &discard_list);
2854 osc_update_pending(obj, OBD_BRW_WRITE,
2855 -ext->oe_nr_pages);
2856 }
2857 break;
2858 case OES_ACTIVE:
2859 /* It's pretty bad to wait for ACTIVE extents, because
2860 * we don't know how long we will wait for it to be
2861 * flushed since it may be blocked at awaiting more
2862 * grants. We do this for the correctness of fsync. */
2863 LASSERT(hp == 0 && discard == 0);
2864 ext->oe_urgent = 1;
2865 break;
2866 case OES_TRUNC:
2867 /* this extent is being truncated, can't do anything
2868 * for it now. it will be set to urgent after truncate
2869 * is finished in osc_cache_truncate_end(). */
2870 default:
2871 break;
2872 }
2873 ext = next_extent(ext);
2874 }
2875 osc_object_unlock(obj);
2876
2877 LASSERT(ergo(!discard, list_empty(&discard_list)));
2878 if (!list_empty(&discard_list)) {
2879 struct osc_extent *tmp;
2880 int rc;
2881
2882 osc_list_maint(osc_cli(obj), obj);
2883 list_for_each_entry_safe(ext, tmp, &discard_list, oe_link) {
2884 list_del_init(&ext->oe_link);
2885 EASSERT(ext->oe_state == OES_LOCKING, ext);
2886
2887 /* Discard caching pages. We don't actually write this
2888 * extent out but we complete it as if we did. */
2889 rc = osc_extent_make_ready(env, ext);
2890 if (unlikely(rc < 0)) {
2891 OSC_EXTENT_DUMP(D_ERROR, ext,
2892 "make_ready returned %d\n", rc);
2893 if (result >= 0)
2894 result = rc;
2895 }
2896
2897 /* finish the extent as if the pages were sent */
2898 osc_extent_finish(env, ext, 0, 0);
2899 }
2900 }
2901
2902 if (unplug)
2903 osc_io_unplug(env, osc_cli(obj), obj, PDL_POLICY_ROUND);
2904
2905 if (hp || discard) {
2906 int rc;
2907 rc = osc_cache_wait_range(env, obj, start, end);
2908 if (result >= 0 && rc < 0)
2909 result = rc;
2910 }
2911
2912 OSC_IO_DEBUG(obj, "cache page out.\n");
2913 RETURN(result);
2914}
2915
2916/** @} osc */
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