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37#include <linux/fs.h>
38#include <linux/sched.h>
39#include <linux/mm.h>
40#include <linux/highmem.h>
41#include <linux/pagemap.h>
42
43#define DEBUG_SUBSYSTEM S_LLITE
44
45#include <obd_support.h>
46#include <lustre_lite.h>
47#include <lustre_dlm.h>
48#include "llite_internal.h"
49
50#define SA_OMITTED_ENTRY_MAX 8ULL
51
52typedef enum {
53
54 SA_ENTRY_INIT = 0,
55 SA_ENTRY_SUCC = 1,
56 SA_ENTRY_INVA = 2,
57 SA_ENTRY_DEST = 3,
58} se_stat_t;
59
60struct ll_sa_entry {
61
62 struct list_head se_link;
63
64 struct list_head se_list;
65
66 struct list_head se_hash;
67
68 atomic_t se_refcount;
69
70 __u64 se_index;
71
72 __u64 se_handle;
73
74 se_stat_t se_stat;
75
76 int se_size;
77
78 struct md_enqueue_info *se_minfo;
79
80 struct ptlrpc_request *se_req;
81
82 struct inode *se_inode;
83
84 struct qstr se_qstr;
85};
86
87static unsigned int sai_generation = 0;
88static DEFINE_SPINLOCK(sai_generation_lock);
89
90static inline int ll_sa_entry_unhashed(struct ll_sa_entry *entry)
91{
92 return list_empty(&entry->se_hash);
93}
94
95
96
97
98static inline int ll_sa_entry_stated(struct ll_sa_entry *entry)
99{
100 smp_rmb();
101 return (entry->se_stat != SA_ENTRY_INIT);
102}
103
104static inline int ll_sa_entry_hash(int val)
105{
106 return val & LL_SA_CACHE_MASK;
107}
108
109
110
111
112static inline void
113ll_sa_entry_enhash(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
114{
115 int i = ll_sa_entry_hash(entry->se_qstr.hash);
116
117 spin_lock(&sai->sai_cache_lock[i]);
118 list_add_tail(&entry->se_hash, &sai->sai_cache[i]);
119 spin_unlock(&sai->sai_cache_lock[i]);
120}
121
122
123
124
125static inline void
126ll_sa_entry_unhash(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
127{
128 int i = ll_sa_entry_hash(entry->se_qstr.hash);
129
130 spin_lock(&sai->sai_cache_lock[i]);
131 list_del_init(&entry->se_hash);
132 spin_unlock(&sai->sai_cache_lock[i]);
133}
134
135static inline int agl_should_run(struct ll_statahead_info *sai,
136 struct inode *inode)
137{
138 return (inode != NULL && S_ISREG(inode->i_mode) && sai->sai_agl_valid);
139}
140
141static inline struct ll_sa_entry *
142sa_first_received_entry(struct ll_statahead_info *sai)
143{
144 return list_entry(sai->sai_entries_received.next,
145 struct ll_sa_entry, se_list);
146}
147
148static inline struct ll_inode_info *
149agl_first_entry(struct ll_statahead_info *sai)
150{
151 return list_entry(sai->sai_entries_agl.next,
152 struct ll_inode_info, lli_agl_list);
153}
154
155static inline int sa_sent_full(struct ll_statahead_info *sai)
156{
157 return atomic_read(&sai->sai_cache_count) >= sai->sai_max;
158}
159
160static inline int sa_received_empty(struct ll_statahead_info *sai)
161{
162 return list_empty(&sai->sai_entries_received);
163}
164
165static inline int agl_list_empty(struct ll_statahead_info *sai)
166{
167 return list_empty(&sai->sai_entries_agl);
168}
169
170
171
172
173
174
175
176static inline int sa_low_hit(struct ll_statahead_info *sai)
177{
178 return ((sai->sai_hit > 7 && sai->sai_hit < 4 * sai->sai_miss) ||
179 (sai->sai_consecutive_miss > 8));
180}
181
182
183
184
185
186static inline int is_omitted_entry(struct ll_statahead_info *sai, __u64 index)
187{
188 return ((__u64)sai->sai_max + index + SA_OMITTED_ENTRY_MAX <
189 sai->sai_index);
190}
191
192
193
194
195static struct ll_sa_entry *
196ll_sa_entry_alloc(struct ll_statahead_info *sai, __u64 index,
197 const char *name, int len)
198{
199 struct ll_inode_info *lli;
200 struct ll_sa_entry *entry;
201 int entry_size;
202 char *dname;
203
204 entry_size = sizeof(struct ll_sa_entry) + (len & ~3) + 4;
205 OBD_ALLOC(entry, entry_size);
206 if (unlikely(entry == NULL))
207 return ERR_PTR(-ENOMEM);
208
209 CDEBUG(D_READA, "alloc sa entry %.*s(%p) index "LPU64"\n",
210 len, name, entry, index);
211
212 entry->se_index = index;
213
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234
235
236
237 atomic_set(&entry->se_refcount, 2);
238 entry->se_stat = SA_ENTRY_INIT;
239 entry->se_size = entry_size;
240 dname = (char *)entry + sizeof(struct ll_sa_entry);
241 memcpy(dname, name, len);
242 dname[len] = 0;
243 entry->se_qstr.hash = full_name_hash(name, len);
244 entry->se_qstr.len = len;
245 entry->se_qstr.name = dname;
246
247 lli = ll_i2info(sai->sai_inode);
248 spin_lock(&lli->lli_sa_lock);
249 list_add_tail(&entry->se_link, &sai->sai_entries);
250 INIT_LIST_HEAD(&entry->se_list);
251 ll_sa_entry_enhash(sai, entry);
252 spin_unlock(&lli->lli_sa_lock);
253
254 atomic_inc(&sai->sai_cache_count);
255
256 return entry;
257}
258
259
260
261
262
263
264
265
266static struct ll_sa_entry *
267ll_sa_entry_get_byname(struct ll_statahead_info *sai, const struct qstr *qstr)
268{
269 struct ll_sa_entry *entry;
270 int i = ll_sa_entry_hash(qstr->hash);
271
272 list_for_each_entry(entry, &sai->sai_cache[i], se_hash) {
273 if (entry->se_qstr.hash == qstr->hash &&
274 entry->se_qstr.len == qstr->len &&
275 memcmp(entry->se_qstr.name, qstr->name, qstr->len) == 0)
276 return entry;
277 }
278 return NULL;
279}
280
281
282
283
284
285
286
287
288static struct ll_sa_entry *
289ll_sa_entry_get_byindex(struct ll_statahead_info *sai, __u64 index)
290{
291 struct ll_sa_entry *entry;
292
293 list_for_each_entry(entry, &sai->sai_entries, se_link) {
294 if (entry->se_index == index) {
295 LASSERT(atomic_read(&entry->se_refcount) > 0);
296 atomic_inc(&entry->se_refcount);
297 return entry;
298 }
299 if (entry->se_index > index)
300 break;
301 }
302 return NULL;
303}
304
305static void ll_sa_entry_cleanup(struct ll_statahead_info *sai,
306 struct ll_sa_entry *entry)
307{
308 struct md_enqueue_info *minfo = entry->se_minfo;
309 struct ptlrpc_request *req = entry->se_req;
310
311 if (minfo) {
312 entry->se_minfo = NULL;
313 ll_intent_release(&minfo->mi_it);
314 iput(minfo->mi_dir);
315 OBD_FREE_PTR(minfo);
316 }
317
318 if (req) {
319 entry->se_req = NULL;
320 ptlrpc_req_finished(req);
321 }
322}
323
324static void ll_sa_entry_put(struct ll_statahead_info *sai,
325 struct ll_sa_entry *entry)
326{
327 if (atomic_dec_and_test(&entry->se_refcount)) {
328 CDEBUG(D_READA, "free sa entry %.*s(%p) index "LPU64"\n",
329 entry->se_qstr.len, entry->se_qstr.name, entry,
330 entry->se_index);
331
332 LASSERT(list_empty(&entry->se_link));
333 LASSERT(list_empty(&entry->se_list));
334 LASSERT(ll_sa_entry_unhashed(entry));
335
336 ll_sa_entry_cleanup(sai, entry);
337 if (entry->se_inode)
338 iput(entry->se_inode);
339
340 OBD_FREE(entry, entry->se_size);
341 atomic_dec(&sai->sai_cache_count);
342 }
343}
344
345static inline void
346do_sa_entry_fini(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
347{
348 struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
349
350 LASSERT(!ll_sa_entry_unhashed(entry));
351 LASSERT(!list_empty(&entry->se_link));
352
353 ll_sa_entry_unhash(sai, entry);
354
355 spin_lock(&lli->lli_sa_lock);
356 entry->se_stat = SA_ENTRY_DEST;
357 list_del_init(&entry->se_link);
358 if (likely(!list_empty(&entry->se_list)))
359 list_del_init(&entry->se_list);
360 spin_unlock(&lli->lli_sa_lock);
361
362 ll_sa_entry_put(sai, entry);
363}
364
365
366
367
368static void
369ll_sa_entry_fini(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
370{
371 struct ll_sa_entry *pos, *next;
372
373 if (entry)
374 do_sa_entry_fini(sai, entry);
375
376
377 list_for_each_entry_safe(pos, next, &sai->sai_entries, se_link) {
378 if (!is_omitted_entry(sai, pos->se_index))
379 break;
380 do_sa_entry_fini(sai, pos);
381 }
382}
383
384
385
386
387static void
388do_sa_entry_to_stated(struct ll_statahead_info *sai,
389 struct ll_sa_entry *entry, se_stat_t stat)
390{
391 struct ll_sa_entry *se;
392 struct list_head *pos = &sai->sai_entries_stated;
393
394 if (!list_empty(&entry->se_list))
395 list_del_init(&entry->se_list);
396
397 list_for_each_entry_reverse(se, &sai->sai_entries_stated, se_list) {
398 if (se->se_index < entry->se_index) {
399 pos = &se->se_list;
400 break;
401 }
402 }
403
404 list_add(&entry->se_list, pos);
405 entry->se_stat = stat;
406}
407
408
409
410
411
412
413static int
414ll_sa_entry_to_stated(struct ll_statahead_info *sai,
415 struct ll_sa_entry *entry, se_stat_t stat)
416{
417 struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
418 int ret = 1;
419
420 ll_sa_entry_cleanup(sai, entry);
421
422 spin_lock(&lli->lli_sa_lock);
423 if (likely(entry->se_stat != SA_ENTRY_DEST)) {
424 do_sa_entry_to_stated(sai, entry, stat);
425 ret = 0;
426 }
427 spin_unlock(&lli->lli_sa_lock);
428
429 return ret;
430}
431
432
433
434
435static void ll_agl_add(struct ll_statahead_info *sai,
436 struct inode *inode, int index)
437{
438 struct ll_inode_info *child = ll_i2info(inode);
439 struct ll_inode_info *parent = ll_i2info(sai->sai_inode);
440 int added = 0;
441
442 spin_lock(&child->lli_agl_lock);
443 if (child->lli_agl_index == 0) {
444 child->lli_agl_index = index;
445 spin_unlock(&child->lli_agl_lock);
446
447 LASSERT(list_empty(&child->lli_agl_list));
448
449 igrab(inode);
450 spin_lock(&parent->lli_agl_lock);
451 if (agl_list_empty(sai))
452 added = 1;
453 list_add_tail(&child->lli_agl_list, &sai->sai_entries_agl);
454 spin_unlock(&parent->lli_agl_lock);
455 } else {
456 spin_unlock(&child->lli_agl_lock);
457 }
458
459 if (added > 0)
460 wake_up(&sai->sai_agl_thread.t_ctl_waitq);
461}
462
463static struct ll_statahead_info *ll_sai_alloc(void)
464{
465 struct ll_statahead_info *sai;
466 int i;
467
468 OBD_ALLOC_PTR(sai);
469 if (!sai)
470 return NULL;
471
472 atomic_set(&sai->sai_refcount, 1);
473
474 spin_lock(&sai_generation_lock);
475 sai->sai_generation = ++sai_generation;
476 if (unlikely(sai_generation == 0))
477 sai->sai_generation = ++sai_generation;
478 spin_unlock(&sai_generation_lock);
479
480 sai->sai_max = LL_SA_RPC_MIN;
481 sai->sai_index = 1;
482 init_waitqueue_head(&sai->sai_waitq);
483 init_waitqueue_head(&sai->sai_thread.t_ctl_waitq);
484 init_waitqueue_head(&sai->sai_agl_thread.t_ctl_waitq);
485
486 INIT_LIST_HEAD(&sai->sai_entries);
487 INIT_LIST_HEAD(&sai->sai_entries_received);
488 INIT_LIST_HEAD(&sai->sai_entries_stated);
489 INIT_LIST_HEAD(&sai->sai_entries_agl);
490
491 for (i = 0; i < LL_SA_CACHE_SIZE; i++) {
492 INIT_LIST_HEAD(&sai->sai_cache[i]);
493 spin_lock_init(&sai->sai_cache_lock[i]);
494 }
495 atomic_set(&sai->sai_cache_count, 0);
496
497 return sai;
498}
499
500static inline struct ll_statahead_info *
501ll_sai_get(struct ll_statahead_info *sai)
502{
503 atomic_inc(&sai->sai_refcount);
504 return sai;
505}
506
507static void ll_sai_put(struct ll_statahead_info *sai)
508{
509 struct inode *inode = sai->sai_inode;
510 struct ll_inode_info *lli = ll_i2info(inode);
511
512 if (atomic_dec_and_lock(&sai->sai_refcount, &lli->lli_sa_lock)) {
513 struct ll_sa_entry *entry, *next;
514
515 if (unlikely(atomic_read(&sai->sai_refcount) > 0)) {
516
517
518 spin_unlock(&lli->lli_sa_lock);
519 return;
520 }
521
522 LASSERT(lli->lli_opendir_key == NULL);
523 LASSERT(thread_is_stopped(&sai->sai_thread));
524 LASSERT(thread_is_stopped(&sai->sai_agl_thread));
525
526 lli->lli_sai = NULL;
527 lli->lli_opendir_pid = 0;
528 spin_unlock(&lli->lli_sa_lock);
529
530 if (sai->sai_sent > sai->sai_replied)
531 CDEBUG(D_READA,"statahead for dir "DFID" does not "
532 "finish: [sent:"LPU64"] [replied:"LPU64"]\n",
533 PFID(&lli->lli_fid),
534 sai->sai_sent, sai->sai_replied);
535
536 list_for_each_entry_safe(entry, next,
537 &sai->sai_entries, se_link)
538 do_sa_entry_fini(sai, entry);
539
540 LASSERT(list_empty(&sai->sai_entries));
541 LASSERT(sa_received_empty(sai));
542 LASSERT(list_empty(&sai->sai_entries_stated));
543
544 LASSERT(atomic_read(&sai->sai_cache_count) == 0);
545 LASSERT(agl_list_empty(sai));
546
547 iput(inode);
548 OBD_FREE_PTR(sai);
549 }
550}
551
552
553static void ll_agl_trigger(struct inode *inode, struct ll_statahead_info *sai)
554{
555 struct ll_inode_info *lli = ll_i2info(inode);
556 __u64 index = lli->lli_agl_index;
557 int rc;
558
559 LASSERT(list_empty(&lli->lli_agl_list));
560
561
562 if (is_omitted_entry(sai, index + 1)) {
563 lli->lli_agl_index = 0;
564 iput(inode);
565 return;
566 }
567
568
569 rc = down_write_trylock(&lli->lli_glimpse_sem);
570 if (rc == 0) {
571 lli->lli_agl_index = 0;
572 iput(inode);
573 return;
574 }
575
576
577
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586
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588
589 if (lli->lli_glimpse_time != 0 &&
590 cfs_time_before(cfs_time_shift(-1), lli->lli_glimpse_time)) {
591 up_write(&lli->lli_glimpse_sem);
592 lli->lli_agl_index = 0;
593 iput(inode);
594 return;
595 }
596
597 CDEBUG(D_READA, "Handling (init) async glimpse: inode = "
598 DFID", idx = "LPU64"\n", PFID(&lli->lli_fid), index);
599
600 cl_agl(inode);
601 lli->lli_agl_index = 0;
602 lli->lli_glimpse_time = cfs_time_current();
603 up_write(&lli->lli_glimpse_sem);
604
605 CDEBUG(D_READA, "Handled (init) async glimpse: inode= "
606 DFID", idx = "LPU64", rc = %d\n",
607 PFID(&lli->lli_fid), index, rc);
608
609 iput(inode);
610}
611
612static void ll_post_statahead(struct ll_statahead_info *sai)
613{
614 struct inode *dir = sai->sai_inode;
615 struct inode *child;
616 struct ll_inode_info *lli = ll_i2info(dir);
617 struct ll_sa_entry *entry;
618 struct md_enqueue_info *minfo;
619 struct lookup_intent *it;
620 struct ptlrpc_request *req;
621 struct mdt_body *body;
622 int rc = 0;
623
624 spin_lock(&lli->lli_sa_lock);
625 if (unlikely(sa_received_empty(sai))) {
626 spin_unlock(&lli->lli_sa_lock);
627 return;
628 }
629 entry = sa_first_received_entry(sai);
630 atomic_inc(&entry->se_refcount);
631 list_del_init(&entry->se_list);
632 spin_unlock(&lli->lli_sa_lock);
633
634 LASSERT(entry->se_handle != 0);
635
636 minfo = entry->se_minfo;
637 it = &minfo->mi_it;
638 req = entry->se_req;
639 body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
640 if (body == NULL)
641 GOTO(out, rc = -EFAULT);
642
643 child = entry->se_inode;
644 if (child == NULL) {
645
646
647
648 LASSERT(fid_is_zero(&minfo->mi_data.op_fid2));
649
650
651
652 if (body->valid & OBD_MD_MDS)
653 GOTO(out, rc = -EAGAIN);
654 } else {
655
656
657
658
659 if (unlikely(!lu_fid_eq(&minfo->mi_data.op_fid2, &body->fid1))){
660 entry->se_inode = NULL;
661 iput(child);
662 child = NULL;
663 }
664 }
665
666 it->d.lustre.it_lock_handle = entry->se_handle;
667 rc = md_revalidate_lock(ll_i2mdexp(dir), it, ll_inode2fid(dir), NULL);
668 if (rc != 1)
669 GOTO(out, rc = -EAGAIN);
670
671 rc = ll_prep_inode(&child, req, dir->i_sb, it);
672 if (rc)
673 GOTO(out, rc);
674
675 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
676 child, child->i_ino, child->i_generation);
677 ll_set_lock_data(ll_i2sbi(dir)->ll_md_exp, child, it, NULL);
678
679 entry->se_inode = child;
680
681 if (agl_should_run(sai, child))
682 ll_agl_add(sai, child, entry->se_index);
683
684out:
685
686
687
688
689 rc = ll_sa_entry_to_stated(sai, entry,
690 rc < 0 ? SA_ENTRY_INVA : SA_ENTRY_SUCC);
691 if (rc == 0 && entry->se_index == sai->sai_index_wait)
692 wake_up(&sai->sai_waitq);
693 ll_sa_entry_put(sai, entry);
694}
695
696static int ll_statahead_interpret(struct ptlrpc_request *req,
697 struct md_enqueue_info *minfo, int rc)
698{
699 struct lookup_intent *it = &minfo->mi_it;
700 struct inode *dir = minfo->mi_dir;
701 struct ll_inode_info *lli = ll_i2info(dir);
702 struct ll_statahead_info *sai = NULL;
703 struct ll_sa_entry *entry;
704 int wakeup;
705
706 if (it_disposition(it, DISP_LOOKUP_NEG))
707 rc = -ENOENT;
708
709 spin_lock(&lli->lli_sa_lock);
710
711 if (unlikely(lli->lli_sai == NULL ||
712 lli->lli_sai->sai_generation != minfo->mi_generation)) {
713 spin_unlock(&lli->lli_sa_lock);
714 GOTO(out, rc = -ESTALE);
715 } else {
716 sai = ll_sai_get(lli->lli_sai);
717 if (unlikely(!thread_is_running(&sai->sai_thread))) {
718 sai->sai_replied++;
719 spin_unlock(&lli->lli_sa_lock);
720 GOTO(out, rc = -EBADFD);
721 }
722
723 entry = ll_sa_entry_get_byindex(sai, minfo->mi_cbdata);
724 if (entry == NULL) {
725 sai->sai_replied++;
726 spin_unlock(&lli->lli_sa_lock);
727 GOTO(out, rc = -EIDRM);
728 }
729
730 if (rc != 0) {
731 do_sa_entry_to_stated(sai, entry, SA_ENTRY_INVA);
732 wakeup = (entry->se_index == sai->sai_index_wait);
733 } else {
734 entry->se_minfo = minfo;
735 entry->se_req = ptlrpc_request_addref(req);
736
737
738
739
740 entry->se_handle = it->d.lustre.it_lock_handle;
741 ll_intent_drop_lock(it);
742 wakeup = sa_received_empty(sai);
743 list_add_tail(&entry->se_list,
744 &sai->sai_entries_received);
745 }
746 sai->sai_replied++;
747 spin_unlock(&lli->lli_sa_lock);
748
749 ll_sa_entry_put(sai, entry);
750 if (wakeup)
751 wake_up(&sai->sai_thread.t_ctl_waitq);
752 }
753
754out:
755 if (rc != 0) {
756 ll_intent_release(it);
757 iput(dir);
758 OBD_FREE_PTR(minfo);
759 }
760 if (sai != NULL)
761 ll_sai_put(sai);
762 return rc;
763}
764
765static void sa_args_fini(struct md_enqueue_info *minfo,
766 struct ldlm_enqueue_info *einfo)
767{
768 LASSERT(minfo && einfo);
769 iput(minfo->mi_dir);
770 capa_put(minfo->mi_data.op_capa1);
771 capa_put(minfo->mi_data.op_capa2);
772 OBD_FREE_PTR(minfo);
773 OBD_FREE_PTR(einfo);
774}
775
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782
783
784
785static int sa_args_init(struct inode *dir, struct inode *child,
786 struct ll_sa_entry *entry, struct md_enqueue_info **pmi,
787 struct ldlm_enqueue_info **pei,
788 struct obd_capa **pcapa)
789{
790 struct qstr *qstr = &entry->se_qstr;
791 struct ll_inode_info *lli = ll_i2info(dir);
792 struct md_enqueue_info *minfo;
793 struct ldlm_enqueue_info *einfo;
794 struct md_op_data *op_data;
795
796 OBD_ALLOC_PTR(einfo);
797 if (einfo == NULL)
798 return -ENOMEM;
799
800 OBD_ALLOC_PTR(minfo);
801 if (minfo == NULL) {
802 OBD_FREE_PTR(einfo);
803 return -ENOMEM;
804 }
805
806 op_data = ll_prep_md_op_data(&minfo->mi_data, dir, child, qstr->name,
807 qstr->len, 0, LUSTRE_OPC_ANY, NULL);
808 if (IS_ERR(op_data)) {
809 OBD_FREE_PTR(einfo);
810 OBD_FREE_PTR(minfo);
811 return PTR_ERR(op_data);
812 }
813
814 minfo->mi_it.it_op = IT_GETATTR;
815 minfo->mi_dir = igrab(dir);
816 minfo->mi_cb = ll_statahead_interpret;
817 minfo->mi_generation = lli->lli_sai->sai_generation;
818 minfo->mi_cbdata = entry->se_index;
819
820 einfo->ei_type = LDLM_IBITS;
821 einfo->ei_mode = it_to_lock_mode(&minfo->mi_it);
822 einfo->ei_cb_bl = ll_md_blocking_ast;
823 einfo->ei_cb_cp = ldlm_completion_ast;
824 einfo->ei_cb_gl = NULL;
825 einfo->ei_cbdata = NULL;
826
827 *pmi = minfo;
828 *pei = einfo;
829 pcapa[0] = op_data->op_capa1;
830 pcapa[1] = op_data->op_capa2;
831
832 return 0;
833}
834
835static int do_sa_lookup(struct inode *dir, struct ll_sa_entry *entry)
836{
837 struct md_enqueue_info *minfo;
838 struct ldlm_enqueue_info *einfo;
839 struct obd_capa *capas[2];
840 int rc;
841
842 rc = sa_args_init(dir, NULL, entry, &minfo, &einfo, capas);
843 if (rc)
844 return rc;
845
846 rc = md_intent_getattr_async(ll_i2mdexp(dir), minfo, einfo);
847 if (!rc) {
848 capa_put(capas[0]);
849 capa_put(capas[1]);
850 } else {
851 sa_args_fini(minfo, einfo);
852 }
853
854 return rc;
855}
856
857
858
859
860
861
862
863static int do_sa_revalidate(struct inode *dir, struct ll_sa_entry *entry,
864 struct dentry *dentry)
865{
866 struct inode *inode = dentry->d_inode;
867 struct lookup_intent it = { .it_op = IT_GETATTR,
868 .d.lustre.it_lock_handle = 0 };
869 struct md_enqueue_info *minfo;
870 struct ldlm_enqueue_info *einfo;
871 struct obd_capa *capas[2];
872 int rc;
873
874 if (unlikely(inode == NULL))
875 return 1;
876
877 if (d_mountpoint(dentry))
878 return 1;
879
880 if (unlikely(dentry == dentry->d_sb->s_root))
881 return 1;
882
883 entry->se_inode = igrab(inode);
884 rc = md_revalidate_lock(ll_i2mdexp(dir), &it, ll_inode2fid(inode),NULL);
885 if (rc == 1) {
886 entry->se_handle = it.d.lustre.it_lock_handle;
887 ll_intent_release(&it);
888 return 1;
889 }
890
891 rc = sa_args_init(dir, inode, entry, &minfo, &einfo, capas);
892 if (rc) {
893 entry->se_inode = NULL;
894 iput(inode);
895 return rc;
896 }
897
898 rc = md_intent_getattr_async(ll_i2mdexp(dir), minfo, einfo);
899 if (!rc) {
900 capa_put(capas[0]);
901 capa_put(capas[1]);
902 } else {
903 entry->se_inode = NULL;
904 iput(inode);
905 sa_args_fini(minfo, einfo);
906 }
907
908 return rc;
909}
910
911static void ll_statahead_one(struct dentry *parent, const char* entry_name,
912 int entry_name_len)
913{
914 struct inode *dir = parent->d_inode;
915 struct ll_inode_info *lli = ll_i2info(dir);
916 struct ll_statahead_info *sai = lli->lli_sai;
917 struct dentry *dentry = NULL;
918 struct ll_sa_entry *entry;
919 int rc;
920 int rc1;
921
922 entry = ll_sa_entry_alloc(sai, sai->sai_index, entry_name,
923 entry_name_len);
924 if (IS_ERR(entry))
925 return;
926
927 dentry = d_lookup(parent, &entry->se_qstr);
928 if (!dentry) {
929 rc = do_sa_lookup(dir, entry);
930 } else {
931 rc = do_sa_revalidate(dir, entry, dentry);
932 if (rc == 1 && agl_should_run(sai, dentry->d_inode))
933 ll_agl_add(sai, dentry->d_inode, entry->se_index);
934 }
935
936 if (dentry != NULL)
937 dput(dentry);
938
939 if (rc) {
940 rc1 = ll_sa_entry_to_stated(sai, entry,
941 rc < 0 ? SA_ENTRY_INVA : SA_ENTRY_SUCC);
942 if (rc1 == 0 && entry->se_index == sai->sai_index_wait)
943 wake_up(&sai->sai_waitq);
944 } else {
945 sai->sai_sent++;
946 }
947
948 sai->sai_index++;
949
950 ll_sa_entry_put(sai, entry);
951}
952
953static int ll_agl_thread(void *arg)
954{
955 struct dentry *parent = (struct dentry *)arg;
956 struct inode *dir = parent->d_inode;
957 struct ll_inode_info *plli = ll_i2info(dir);
958 struct ll_inode_info *clli;
959 struct ll_sb_info *sbi = ll_i2sbi(dir);
960 struct ll_statahead_info *sai = ll_sai_get(plli->lli_sai);
961 struct ptlrpc_thread *thread = &sai->sai_agl_thread;
962 struct l_wait_info lwi = { 0 };
963
964 CDEBUG(D_READA, "agl thread started: [pid %d] [parent %.*s]\n",
965 current_pid(), parent->d_name.len, parent->d_name.name);
966
967 atomic_inc(&sbi->ll_agl_total);
968 spin_lock(&plli->lli_agl_lock);
969 sai->sai_agl_valid = 1;
970 thread_set_flags(thread, SVC_RUNNING);
971 spin_unlock(&plli->lli_agl_lock);
972 wake_up(&thread->t_ctl_waitq);
973
974 while (1) {
975 l_wait_event(thread->t_ctl_waitq,
976 !agl_list_empty(sai) ||
977 !thread_is_running(thread),
978 &lwi);
979
980 if (!thread_is_running(thread))
981 break;
982
983 spin_lock(&plli->lli_agl_lock);
984
985
986 if (!agl_list_empty(sai)) {
987 clli = agl_first_entry(sai);
988 list_del_init(&clli->lli_agl_list);
989 spin_unlock(&plli->lli_agl_lock);
990 ll_agl_trigger(&clli->lli_vfs_inode, sai);
991 } else {
992 spin_unlock(&plli->lli_agl_lock);
993 }
994 }
995
996 spin_lock(&plli->lli_agl_lock);
997 sai->sai_agl_valid = 0;
998 while (!agl_list_empty(sai)) {
999 clli = agl_first_entry(sai);
1000 list_del_init(&clli->lli_agl_list);
1001 spin_unlock(&plli->lli_agl_lock);
1002 clli->lli_agl_index = 0;
1003 iput(&clli->lli_vfs_inode);
1004 spin_lock(&plli->lli_agl_lock);
1005 }
1006 thread_set_flags(thread, SVC_STOPPED);
1007 spin_unlock(&plli->lli_agl_lock);
1008 wake_up(&thread->t_ctl_waitq);
1009 ll_sai_put(sai);
1010 CDEBUG(D_READA, "agl thread stopped: [pid %d] [parent %.*s]\n",
1011 current_pid(), parent->d_name.len, parent->d_name.name);
1012 return 0;
1013}
1014
1015static void ll_start_agl(struct dentry *parent, struct ll_statahead_info *sai)
1016{
1017 struct ptlrpc_thread *thread = &sai->sai_agl_thread;
1018 struct l_wait_info lwi = { 0 };
1019 struct ll_inode_info *plli;
1020 struct task_struct *task;
1021
1022 CDEBUG(D_READA, "start agl thread: [pid %d] [parent %.*s]\n",
1023 current_pid(), parent->d_name.len, parent->d_name.name);
1024
1025 plli = ll_i2info(parent->d_inode);
1026 task = kthread_run(ll_agl_thread, parent,
1027 "ll_agl_%u", plli->lli_opendir_pid);
1028 if (IS_ERR(task)) {
1029 CERROR("can't start ll_agl thread, rc: %ld\n", PTR_ERR(task));
1030 thread_set_flags(thread, SVC_STOPPED);
1031 return;
1032 }
1033
1034 l_wait_event(thread->t_ctl_waitq,
1035 thread_is_running(thread) || thread_is_stopped(thread),
1036 &lwi);
1037}
1038
1039static int ll_statahead_thread(void *arg)
1040{
1041 struct dentry *parent = (struct dentry *)arg;
1042 struct inode *dir = parent->d_inode;
1043 struct ll_inode_info *plli = ll_i2info(dir);
1044 struct ll_inode_info *clli;
1045 struct ll_sb_info *sbi = ll_i2sbi(dir);
1046 struct ll_statahead_info *sai = ll_sai_get(plli->lli_sai);
1047 struct ptlrpc_thread *thread = &sai->sai_thread;
1048 struct ptlrpc_thread *agl_thread = &sai->sai_agl_thread;
1049 struct page *page;
1050 __u64 pos = 0;
1051 int first = 0;
1052 int rc = 0;
1053 struct ll_dir_chain chain;
1054 struct l_wait_info lwi = { 0 };
1055
1056 CDEBUG(D_READA, "statahead thread started: [pid %d] [parent %.*s]\n",
1057 current_pid(), parent->d_name.len, parent->d_name.name);
1058
1059 if (sbi->ll_flags & LL_SBI_AGL_ENABLED)
1060 ll_start_agl(parent, sai);
1061
1062 atomic_inc(&sbi->ll_sa_total);
1063 spin_lock(&plli->lli_sa_lock);
1064 thread_set_flags(thread, SVC_RUNNING);
1065 spin_unlock(&plli->lli_sa_lock);
1066 wake_up(&thread->t_ctl_waitq);
1067
1068 ll_dir_chain_init(&chain);
1069 page = ll_get_dir_page(dir, pos, &chain);
1070
1071 while (1) {
1072 struct lu_dirpage *dp;
1073 struct lu_dirent *ent;
1074
1075 if (IS_ERR(page)) {
1076 rc = PTR_ERR(page);
1077 CDEBUG(D_READA, "error reading dir "DFID" at "LPU64
1078 "/"LPU64": [rc %d] [parent %u]\n",
1079 PFID(ll_inode2fid(dir)), pos, sai->sai_index,
1080 rc, plli->lli_opendir_pid);
1081 GOTO(out, rc);
1082 }
1083
1084 dp = page_address(page);
1085 for (ent = lu_dirent_start(dp); ent != NULL;
1086 ent = lu_dirent_next(ent)) {
1087 __u64 hash;
1088 int namelen;
1089 char *name;
1090
1091 hash = le64_to_cpu(ent->lde_hash);
1092 if (unlikely(hash < pos))
1093
1094
1095
1096 continue;
1097
1098 namelen = le16_to_cpu(ent->lde_namelen);
1099 if (unlikely(namelen == 0))
1100
1101
1102
1103 continue;
1104
1105 name = ent->lde_name;
1106 if (name[0] == '.') {
1107 if (namelen == 1) {
1108
1109
1110
1111 continue;
1112 } else if (name[1] == '.' && namelen == 2) {
1113
1114
1115
1116 continue;
1117 } else if (!sai->sai_ls_all) {
1118
1119
1120
1121 sai->sai_skip_hidden++;
1122 continue;
1123 }
1124 }
1125
1126
1127
1128
1129 if (unlikely(++first == 1))
1130 continue;
1131
1132keep_it:
1133 l_wait_event(thread->t_ctl_waitq,
1134 !sa_sent_full(sai) ||
1135 !sa_received_empty(sai) ||
1136 !agl_list_empty(sai) ||
1137 !thread_is_running(thread),
1138 &lwi);
1139
1140interpret_it:
1141 while (!sa_received_empty(sai))
1142 ll_post_statahead(sai);
1143
1144 if (unlikely(!thread_is_running(thread))) {
1145 ll_release_page(page, 0);
1146 GOTO(out, rc = 0);
1147 }
1148
1149
1150
1151
1152 if (sa_sent_full(sai)) {
1153 spin_lock(&plli->lli_agl_lock);
1154 while (!agl_list_empty(sai)) {
1155 clli = agl_first_entry(sai);
1156 list_del_init(&clli->lli_agl_list);
1157 spin_unlock(&plli->lli_agl_lock);
1158 ll_agl_trigger(&clli->lli_vfs_inode,
1159 sai);
1160
1161 if (!sa_received_empty(sai))
1162 goto interpret_it;
1163
1164 if (unlikely(
1165 !thread_is_running(thread))) {
1166 ll_release_page(page, 0);
1167 GOTO(out, rc = 0);
1168 }
1169
1170 if (!sa_sent_full(sai))
1171 goto do_it;
1172
1173 spin_lock(&plli->lli_agl_lock);
1174 }
1175 spin_unlock(&plli->lli_agl_lock);
1176
1177 goto keep_it;
1178 }
1179
1180do_it:
1181 ll_statahead_one(parent, name, namelen);
1182 }
1183 pos = le64_to_cpu(dp->ldp_hash_end);
1184 if (pos == MDS_DIR_END_OFF) {
1185
1186
1187
1188 ll_release_page(page, 0);
1189 while (1) {
1190 l_wait_event(thread->t_ctl_waitq,
1191 !sa_received_empty(sai) ||
1192 sai->sai_sent == sai->sai_replied||
1193 !thread_is_running(thread),
1194 &lwi);
1195
1196 while (!sa_received_empty(sai))
1197 ll_post_statahead(sai);
1198
1199 if (unlikely(!thread_is_running(thread)))
1200 GOTO(out, rc = 0);
1201
1202 if (sai->sai_sent == sai->sai_replied &&
1203 sa_received_empty(sai))
1204 break;
1205 }
1206
1207 spin_lock(&plli->lli_agl_lock);
1208 while (!agl_list_empty(sai) &&
1209 thread_is_running(thread)) {
1210 clli = agl_first_entry(sai);
1211 list_del_init(&clli->lli_agl_list);
1212 spin_unlock(&plli->lli_agl_lock);
1213 ll_agl_trigger(&clli->lli_vfs_inode, sai);
1214 spin_lock(&plli->lli_agl_lock);
1215 }
1216 spin_unlock(&plli->lli_agl_lock);
1217
1218 GOTO(out, rc = 0);
1219 } else if (1) {
1220
1221
1222
1223
1224 ll_release_page(page, le32_to_cpu(dp->ldp_flags) &
1225 LDF_COLLIDE);
1226 sai->sai_in_readpage = 1;
1227 page = ll_get_dir_page(dir, pos, &chain);
1228 sai->sai_in_readpage = 0;
1229 } else {
1230 LASSERT(le32_to_cpu(dp->ldp_flags) & LDF_COLLIDE);
1231 ll_release_page(page, 1);
1232
1233
1234
1235 }
1236 }
1237
1238out:
1239 if (sai->sai_agl_valid) {
1240 spin_lock(&plli->lli_agl_lock);
1241 thread_set_flags(agl_thread, SVC_STOPPING);
1242 spin_unlock(&plli->lli_agl_lock);
1243 wake_up(&agl_thread->t_ctl_waitq);
1244
1245 CDEBUG(D_READA, "stop agl thread: [pid %d]\n",
1246 current_pid());
1247 l_wait_event(agl_thread->t_ctl_waitq,
1248 thread_is_stopped(agl_thread),
1249 &lwi);
1250 } else {
1251
1252 thread_set_flags(&sai->sai_agl_thread, SVC_STOPPED);
1253 }
1254 ll_dir_chain_fini(&chain);
1255 spin_lock(&plli->lli_sa_lock);
1256 if (!sa_received_empty(sai)) {
1257 thread_set_flags(thread, SVC_STOPPING);
1258 spin_unlock(&plli->lli_sa_lock);
1259
1260
1261 while (!sa_received_empty(sai))
1262 ll_post_statahead(sai);
1263
1264 spin_lock(&plli->lli_sa_lock);
1265 }
1266 thread_set_flags(thread, SVC_STOPPED);
1267 spin_unlock(&plli->lli_sa_lock);
1268 wake_up(&sai->sai_waitq);
1269 wake_up(&thread->t_ctl_waitq);
1270 ll_sai_put(sai);
1271 dput(parent);
1272 CDEBUG(D_READA, "statahead thread stopped: [pid %d] [parent %.*s]\n",
1273 current_pid(), parent->d_name.len, parent->d_name.name);
1274 return rc;
1275}
1276
1277
1278
1279
1280void ll_stop_statahead(struct inode *dir, void *key)
1281{
1282 struct ll_inode_info *lli = ll_i2info(dir);
1283
1284 if (unlikely(key == NULL))
1285 return;
1286
1287 spin_lock(&lli->lli_sa_lock);
1288 if (lli->lli_opendir_key != key || lli->lli_opendir_pid == 0) {
1289 spin_unlock(&lli->lli_sa_lock);
1290 return;
1291 }
1292
1293 lli->lli_opendir_key = NULL;
1294
1295 if (lli->lli_sai) {
1296 struct l_wait_info lwi = { 0 };
1297 struct ptlrpc_thread *thread = &lli->lli_sai->sai_thread;
1298
1299 if (!thread_is_stopped(thread)) {
1300 thread_set_flags(thread, SVC_STOPPING);
1301 spin_unlock(&lli->lli_sa_lock);
1302 wake_up(&thread->t_ctl_waitq);
1303
1304 CDEBUG(D_READA, "stop statahead thread: [pid %d]\n",
1305 current_pid());
1306 l_wait_event(thread->t_ctl_waitq,
1307 thread_is_stopped(thread),
1308 &lwi);
1309 } else {
1310 spin_unlock(&lli->lli_sa_lock);
1311 }
1312
1313
1314
1315
1316
1317
1318 ll_sai_put(lli->lli_sai);
1319 } else {
1320 lli->lli_opendir_pid = 0;
1321 spin_unlock(&lli->lli_sa_lock);
1322 }
1323}
1324
1325enum {
1326
1327
1328
1329 LS_NONE_FIRST_DE = 0,
1330
1331
1332
1333 LS_FIRST_DE,
1334
1335
1336
1337 LS_FIRST_DOT_DE
1338};
1339
1340static int is_first_dirent(struct inode *dir, struct dentry *dentry)
1341{
1342 struct ll_dir_chain chain;
1343 struct qstr *target = &dentry->d_name;
1344 struct page *page;
1345 __u64 pos = 0;
1346 int dot_de;
1347 int rc = LS_NONE_FIRST_DE;
1348
1349 ll_dir_chain_init(&chain);
1350 page = ll_get_dir_page(dir, pos, &chain);
1351
1352 while (1) {
1353 struct lu_dirpage *dp;
1354 struct lu_dirent *ent;
1355
1356 if (IS_ERR(page)) {
1357 struct ll_inode_info *lli = ll_i2info(dir);
1358
1359 rc = PTR_ERR(page);
1360 CERROR("error reading dir "DFID" at "LPU64": "
1361 "[rc %d] [parent %u]\n",
1362 PFID(ll_inode2fid(dir)), pos,
1363 rc, lli->lli_opendir_pid);
1364 break;
1365 }
1366
1367 dp = page_address(page);
1368 for (ent = lu_dirent_start(dp); ent != NULL;
1369 ent = lu_dirent_next(ent)) {
1370 __u64 hash;
1371 int namelen;
1372 char *name;
1373
1374 hash = le64_to_cpu(ent->lde_hash);
1375
1376
1377 if (unlikely(hash < pos))
1378 continue;
1379
1380 namelen = le16_to_cpu(ent->lde_namelen);
1381 if (unlikely(namelen == 0))
1382
1383
1384
1385 continue;
1386
1387 name = ent->lde_name;
1388 if (name[0] == '.') {
1389 if (namelen == 1)
1390
1391
1392
1393 continue;
1394 else if (name[1] == '.' && namelen == 2)
1395
1396
1397
1398 continue;
1399 else
1400 dot_de = 1;
1401 } else {
1402 dot_de = 0;
1403 }
1404
1405 if (dot_de && target->name[0] != '.') {
1406 CDEBUG(D_READA, "%.*s skip hidden file %.*s\n",
1407 target->len, target->name,
1408 namelen, name);
1409 continue;
1410 }
1411
1412 if (target->len != namelen ||
1413 memcmp(target->name, name, namelen) != 0)
1414 rc = LS_NONE_FIRST_DE;
1415 else if (!dot_de)
1416 rc = LS_FIRST_DE;
1417 else
1418 rc = LS_FIRST_DOT_DE;
1419
1420 ll_release_page(page, 0);
1421 GOTO(out, rc);
1422 }
1423 pos = le64_to_cpu(dp->ldp_hash_end);
1424 if (pos == MDS_DIR_END_OFF) {
1425
1426
1427
1428 ll_release_page(page, 0);
1429 break;
1430 } else if (1) {
1431
1432
1433
1434
1435 ll_release_page(page, le32_to_cpu(dp->ldp_flags) &
1436 LDF_COLLIDE);
1437 page = ll_get_dir_page(dir, pos, &chain);
1438 } else {
1439
1440
1441
1442 LASSERT(le32_to_cpu(dp->ldp_flags) & LDF_COLLIDE);
1443 ll_release_page(page, 1);
1444 }
1445 }
1446
1447out:
1448 ll_dir_chain_fini(&chain);
1449 return rc;
1450}
1451
1452static void
1453ll_sai_unplug(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
1454{
1455 struct ptlrpc_thread *thread = &sai->sai_thread;
1456 struct ll_sb_info *sbi = ll_i2sbi(sai->sai_inode);
1457 int hit;
1458
1459 if (entry != NULL && entry->se_stat == SA_ENTRY_SUCC)
1460 hit = 1;
1461 else
1462 hit = 0;
1463
1464 ll_sa_entry_fini(sai, entry);
1465 if (hit) {
1466 sai->sai_hit++;
1467 sai->sai_consecutive_miss = 0;
1468 sai->sai_max = min(2 * sai->sai_max, sbi->ll_sa_max);
1469 } else {
1470 struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
1471
1472 sai->sai_miss++;
1473 sai->sai_consecutive_miss++;
1474 if (sa_low_hit(sai) && thread_is_running(thread)) {
1475 atomic_inc(&sbi->ll_sa_wrong);
1476 CDEBUG(D_READA, "Statahead for dir "DFID" hit "
1477 "ratio too low: hit/miss "LPU64"/"LPU64
1478 ", sent/replied "LPU64"/"LPU64", stopping "
1479 "statahead thread: pid %d\n",
1480 PFID(&lli->lli_fid), sai->sai_hit,
1481 sai->sai_miss, sai->sai_sent,
1482 sai->sai_replied, current_pid());
1483 spin_lock(&lli->lli_sa_lock);
1484 if (!thread_is_stopped(thread))
1485 thread_set_flags(thread, SVC_STOPPING);
1486 spin_unlock(&lli->lli_sa_lock);
1487 }
1488 }
1489
1490 if (!thread_is_stopped(thread))
1491 wake_up(&thread->t_ctl_waitq);
1492}
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503int do_statahead_enter(struct inode *dir, struct dentry **dentryp,
1504 int only_unplug)
1505{
1506 struct ll_inode_info *lli = ll_i2info(dir);
1507 struct ll_statahead_info *sai = lli->lli_sai;
1508 struct dentry *parent;
1509 struct ll_sa_entry *entry;
1510 struct ptlrpc_thread *thread;
1511 struct l_wait_info lwi = { 0 };
1512 int rc = 0;
1513 struct ll_inode_info *plli;
1514
1515 LASSERT(lli->lli_opendir_pid == current_pid());
1516
1517 if (sai) {
1518 thread = &sai->sai_thread;
1519 if (unlikely(thread_is_stopped(thread) &&
1520 list_empty(&sai->sai_entries_stated))) {
1521
1522 ll_stop_statahead(dir, lli->lli_opendir_key);
1523 return -EAGAIN;
1524 }
1525
1526 if ((*dentryp)->d_name.name[0] == '.') {
1527 if (sai->sai_ls_all ||
1528 sai->sai_miss_hidden >= sai->sai_skip_hidden) {
1529
1530
1531
1532
1533
1534 } else {
1535 if (!sai->sai_ls_all)
1536
1537
1538
1539
1540
1541
1542 sai->sai_ls_all = 1;
1543
1544
1545
1546
1547
1548 sai->sai_miss_hidden++;
1549 return -EAGAIN;
1550 }
1551 }
1552
1553 entry = ll_sa_entry_get_byname(sai, &(*dentryp)->d_name);
1554 if (entry == NULL || only_unplug) {
1555 ll_sai_unplug(sai, entry);
1556 return entry ? 1 : -EAGAIN;
1557 }
1558
1559
1560 while (!ll_sa_entry_stated(entry) &&
1561 sai->sai_in_readpage &&
1562 !sa_received_empty(sai))
1563 ll_post_statahead(sai);
1564
1565 if (!ll_sa_entry_stated(entry)) {
1566 sai->sai_index_wait = entry->se_index;
1567 lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(30), NULL,
1568 LWI_ON_SIGNAL_NOOP, NULL);
1569 rc = l_wait_event(sai->sai_waitq,
1570 ll_sa_entry_stated(entry) ||
1571 thread_is_stopped(thread),
1572 &lwi);
1573 if (rc < 0) {
1574 ll_sai_unplug(sai, entry);
1575 return -EAGAIN;
1576 }
1577 }
1578
1579 if (entry->se_stat == SA_ENTRY_SUCC &&
1580 entry->se_inode != NULL) {
1581 struct inode *inode = entry->se_inode;
1582 struct lookup_intent it = { .it_op = IT_GETATTR,
1583 .d.lustre.it_lock_handle =
1584 entry->se_handle };
1585 __u64 bits;
1586
1587 rc = md_revalidate_lock(ll_i2mdexp(dir), &it,
1588 ll_inode2fid(inode), &bits);
1589 if (rc == 1) {
1590 if ((*dentryp)->d_inode == NULL) {
1591 *dentryp = ll_splice_alias(inode,
1592 *dentryp);
1593 } else if ((*dentryp)->d_inode != inode) {
1594
1595 CDEBUG(D_READA,
1596 "stale dentry %.*s inode %lu/%u, "
1597 "statahead inode %lu/%u\n",
1598 (*dentryp)->d_name.len,
1599 (*dentryp)->d_name.name,
1600 (*dentryp)->d_inode->i_ino,
1601 (*dentryp)->d_inode->i_generation,
1602 inode->i_ino,
1603 inode->i_generation);
1604 ll_sai_unplug(sai, entry);
1605 return -ESTALE;
1606 } else {
1607 iput(inode);
1608 }
1609 entry->se_inode = NULL;
1610
1611 if ((bits & MDS_INODELOCK_LOOKUP) &&
1612 d_lustre_invalid(*dentryp))
1613 d_lustre_revalidate(*dentryp);
1614 ll_intent_release(&it);
1615 }
1616 }
1617
1618 ll_sai_unplug(sai, entry);
1619 return rc;
1620 }
1621
1622
1623 rc = is_first_dirent(dir, *dentryp);
1624 if (rc == LS_NONE_FIRST_DE)
1625
1626 GOTO(out, rc = -EAGAIN);
1627
1628 sai = ll_sai_alloc();
1629 if (sai == NULL)
1630 GOTO(out, rc = -ENOMEM);
1631
1632 sai->sai_ls_all = (rc == LS_FIRST_DOT_DE);
1633 sai->sai_inode = igrab(dir);
1634 if (unlikely(sai->sai_inode == NULL)) {
1635 CWARN("Do not start stat ahead on dying inode "DFID"\n",
1636 PFID(&lli->lli_fid));
1637 GOTO(out, rc = -ESTALE);
1638 }
1639
1640
1641 parent = dget((*dentryp)->d_parent);
1642 if (unlikely(sai->sai_inode != parent->d_inode)) {
1643 struct ll_inode_info *nlli = ll_i2info(parent->d_inode);
1644
1645 CWARN("Race condition, someone changed %.*s just now: "
1646 "old parent "DFID", new parent "DFID"\n",
1647 (*dentryp)->d_name.len, (*dentryp)->d_name.name,
1648 PFID(&lli->lli_fid), PFID(&nlli->lli_fid));
1649 dput(parent);
1650 iput(sai->sai_inode);
1651 GOTO(out, rc = -EAGAIN);
1652 }
1653
1654 CDEBUG(D_READA, "start statahead thread: [pid %d] [parent %.*s]\n",
1655 current_pid(), parent->d_name.len, parent->d_name.name);
1656
1657 lli->lli_sai = sai;
1658
1659 plli = ll_i2info(parent->d_inode);
1660 rc = PTR_ERR(kthread_run(ll_statahead_thread, parent,
1661 "ll_sa_%u", plli->lli_opendir_pid));
1662 thread = &sai->sai_thread;
1663 if (IS_ERR_VALUE(rc)) {
1664 CERROR("can't start ll_sa thread, rc: %d\n", rc);
1665 dput(parent);
1666 lli->lli_opendir_key = NULL;
1667 thread_set_flags(thread, SVC_STOPPED);
1668 thread_set_flags(&sai->sai_agl_thread, SVC_STOPPED);
1669 ll_sai_put(sai);
1670 LASSERT(lli->lli_sai == NULL);
1671 return -EAGAIN;
1672 }
1673
1674 l_wait_event(thread->t_ctl_waitq,
1675 thread_is_running(thread) || thread_is_stopped(thread),
1676 &lwi);
1677
1678
1679
1680
1681
1682 return -EAGAIN;
1683
1684out:
1685 if (sai != NULL)
1686 OBD_FREE_PTR(sai);
1687 spin_lock(&lli->lli_sa_lock);
1688 lli->lli_opendir_key = NULL;
1689 lli->lli_opendir_pid = 0;
1690 spin_unlock(&lli->lli_sa_lock);
1691 return rc;
1692}
1693