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5
6
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9#include <linux/sched.h>
10#include <linux/slab.h>
11#include <linux/spinlock.h>
12#include <linux/buffer_head.h>
13#include <linux/delay.h>
14#include <linux/sort.h>
15#include <linux/hash.h>
16#include <linux/jhash.h>
17#include <linux/kallsyms.h>
18#include <linux/gfs2_ondisk.h>
19#include <linux/list.h>
20#include <linux/wait.h>
21#include <linux/module.h>
22#include <linux/uaccess.h>
23#include <linux/seq_file.h>
24#include <linux/debugfs.h>
25#include <linux/kthread.h>
26#include <linux/freezer.h>
27#include <linux/workqueue.h>
28#include <linux/jiffies.h>
29#include <linux/rcupdate.h>
30#include <linux/rculist_bl.h>
31#include <linux/bit_spinlock.h>
32#include <linux/percpu.h>
33#include <linux/list_sort.h>
34#include <linux/lockref.h>
35#include <linux/rhashtable.h>
36
37#include "gfs2.h"
38#include "incore.h"
39#include "glock.h"
40#include "glops.h"
41#include "inode.h"
42#include "lops.h"
43#include "meta_io.h"
44#include "quota.h"
45#include "super.h"
46#include "util.h"
47#include "bmap.h"
48#define CREATE_TRACE_POINTS
49#include "trace_gfs2.h"
50
51struct gfs2_glock_iter {
52 struct gfs2_sbd *sdp;
53 struct rhashtable_iter hti;
54 struct gfs2_glock *gl;
55 loff_t last_pos;
56};
57
58typedef void (*glock_examiner) (struct gfs2_glock * gl);
59
60static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target);
61static void __gfs2_glock_dq(struct gfs2_holder *gh);
62
63static struct dentry *gfs2_root;
64static struct workqueue_struct *glock_workqueue;
65struct workqueue_struct *gfs2_delete_workqueue;
66static LIST_HEAD(lru_list);
67static atomic_t lru_count = ATOMIC_INIT(0);
68static DEFINE_SPINLOCK(lru_lock);
69
70#define GFS2_GL_HASH_SHIFT 15
71#define GFS2_GL_HASH_SIZE BIT(GFS2_GL_HASH_SHIFT)
72
73static const struct rhashtable_params ht_parms = {
74 .nelem_hint = GFS2_GL_HASH_SIZE * 3 / 4,
75 .key_len = offsetofend(struct lm_lockname, ln_type),
76 .key_offset = offsetof(struct gfs2_glock, gl_name),
77 .head_offset = offsetof(struct gfs2_glock, gl_node),
78};
79
80static struct rhashtable gl_hash_table;
81
82#define GLOCK_WAIT_TABLE_BITS 12
83#define GLOCK_WAIT_TABLE_SIZE (1 << GLOCK_WAIT_TABLE_BITS)
84static wait_queue_head_t glock_wait_table[GLOCK_WAIT_TABLE_SIZE] __cacheline_aligned;
85
86struct wait_glock_queue {
87 struct lm_lockname *name;
88 wait_queue_entry_t wait;
89};
90
91static int glock_wake_function(wait_queue_entry_t *wait, unsigned int mode,
92 int sync, void *key)
93{
94 struct wait_glock_queue *wait_glock =
95 container_of(wait, struct wait_glock_queue, wait);
96 struct lm_lockname *wait_name = wait_glock->name;
97 struct lm_lockname *wake_name = key;
98
99 if (wake_name->ln_sbd != wait_name->ln_sbd ||
100 wake_name->ln_number != wait_name->ln_number ||
101 wake_name->ln_type != wait_name->ln_type)
102 return 0;
103 return autoremove_wake_function(wait, mode, sync, key);
104}
105
106static wait_queue_head_t *glock_waitqueue(struct lm_lockname *name)
107{
108 u32 hash = jhash2((u32 *)name, ht_parms.key_len / 4, 0);
109
110 return glock_wait_table + hash_32(hash, GLOCK_WAIT_TABLE_BITS);
111}
112
113
114
115
116
117static void wake_up_glock(struct gfs2_glock *gl)
118{
119 wait_queue_head_t *wq = glock_waitqueue(&gl->gl_name);
120
121 if (waitqueue_active(wq))
122 __wake_up(wq, TASK_NORMAL, 1, &gl->gl_name);
123}
124
125static void gfs2_glock_dealloc(struct rcu_head *rcu)
126{
127 struct gfs2_glock *gl = container_of(rcu, struct gfs2_glock, gl_rcu);
128
129 kfree(gl->gl_lksb.sb_lvbptr);
130 if (gl->gl_ops->go_flags & GLOF_ASPACE)
131 kmem_cache_free(gfs2_glock_aspace_cachep, gl);
132 else
133 kmem_cache_free(gfs2_glock_cachep, gl);
134}
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149static bool glock_blocked_by_withdraw(struct gfs2_glock *gl)
150{
151 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
152
153 if (likely(!gfs2_withdrawn(sdp)))
154 return false;
155 if (gl->gl_ops->go_flags & GLOF_NONDISK)
156 return false;
157 if (!sdp->sd_jdesc ||
158 gl->gl_name.ln_number == sdp->sd_jdesc->jd_no_addr)
159 return false;
160 return true;
161}
162
163void gfs2_glock_free(struct gfs2_glock *gl)
164{
165 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
166
167 gfs2_glock_assert_withdraw(gl, atomic_read(&gl->gl_revokes) == 0);
168 rhashtable_remove_fast(&gl_hash_table, &gl->gl_node, ht_parms);
169 smp_mb();
170 wake_up_glock(gl);
171 call_rcu(&gl->gl_rcu, gfs2_glock_dealloc);
172 if (atomic_dec_and_test(&sdp->sd_glock_disposal))
173 wake_up(&sdp->sd_glock_wait);
174}
175
176
177
178
179
180
181
182void gfs2_glock_hold(struct gfs2_glock *gl)
183{
184 GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
185 lockref_get(&gl->gl_lockref);
186}
187
188
189
190
191
192
193
194
195static int demote_ok(const struct gfs2_glock *gl)
196{
197 const struct gfs2_glock_operations *glops = gl->gl_ops;
198
199 if (gl->gl_state == LM_ST_UNLOCKED)
200 return 0;
201
202
203
204
205
206
207 if (!list_empty(&gl->gl_holders))
208 return 0;
209 if (glops->go_demote_ok)
210 return glops->go_demote_ok(gl);
211 return 1;
212}
213
214
215void gfs2_glock_add_to_lru(struct gfs2_glock *gl)
216{
217 if (!(gl->gl_ops->go_flags & GLOF_LRU))
218 return;
219
220 spin_lock(&lru_lock);
221
222 list_move_tail(&gl->gl_lru, &lru_list);
223
224 if (!test_bit(GLF_LRU, &gl->gl_flags)) {
225 set_bit(GLF_LRU, &gl->gl_flags);
226 atomic_inc(&lru_count);
227 }
228
229 spin_unlock(&lru_lock);
230}
231
232static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
233{
234 if (!(gl->gl_ops->go_flags & GLOF_LRU))
235 return;
236
237 spin_lock(&lru_lock);
238 if (test_bit(GLF_LRU, &gl->gl_flags)) {
239 list_del_init(&gl->gl_lru);
240 atomic_dec(&lru_count);
241 clear_bit(GLF_LRU, &gl->gl_flags);
242 }
243 spin_unlock(&lru_lock);
244}
245
246
247
248
249
250static void __gfs2_glock_queue_work(struct gfs2_glock *gl, unsigned long delay) {
251 if (!queue_delayed_work(glock_workqueue, &gl->gl_work, delay)) {
252
253
254
255
256
257
258 GLOCK_BUG_ON(gl, gl->gl_lockref.count < 2);
259 gl->gl_lockref.count--;
260 }
261}
262
263static void gfs2_glock_queue_work(struct gfs2_glock *gl, unsigned long delay) {
264 spin_lock(&gl->gl_lockref.lock);
265 __gfs2_glock_queue_work(gl, delay);
266 spin_unlock(&gl->gl_lockref.lock);
267}
268
269static void __gfs2_glock_put(struct gfs2_glock *gl)
270{
271 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
272 struct address_space *mapping = gfs2_glock2aspace(gl);
273
274 lockref_mark_dead(&gl->gl_lockref);
275
276 gfs2_glock_remove_from_lru(gl);
277 spin_unlock(&gl->gl_lockref.lock);
278 GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders));
279 if (mapping) {
280 truncate_inode_pages_final(mapping);
281 if (!gfs2_withdrawn(sdp))
282 GLOCK_BUG_ON(gl, !mapping_empty(mapping));
283 }
284 trace_gfs2_glock_put(gl);
285 sdp->sd_lockstruct.ls_ops->lm_put_lock(gl);
286}
287
288
289
290
291void gfs2_glock_queue_put(struct gfs2_glock *gl)
292{
293 gfs2_glock_queue_work(gl, 0);
294}
295
296
297
298
299
300
301
302void gfs2_glock_put(struct gfs2_glock *gl)
303{
304
305 might_sleep();
306
307 if (lockref_put_or_lock(&gl->gl_lockref))
308 return;
309
310 __gfs2_glock_put(gl);
311}
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327static inline bool may_grant(struct gfs2_glock *gl,
328 struct gfs2_holder *current_gh,
329 struct gfs2_holder *gh)
330{
331 if (current_gh) {
332 GLOCK_BUG_ON(gl, !test_bit(HIF_HOLDER, ¤t_gh->gh_iflags));
333
334 switch(current_gh->gh_state) {
335 case LM_ST_EXCLUSIVE:
336
337
338
339
340
341
342
343 return gh->gh_state == LM_ST_EXCLUSIVE &&
344 (current_gh->gh_flags & LM_FLAG_NODE_SCOPE) &&
345 (gh->gh_flags & LM_FLAG_NODE_SCOPE);
346
347 case LM_ST_SHARED:
348 case LM_ST_DEFERRED:
349 return gh->gh_state == current_gh->gh_state;
350
351 default:
352 return false;
353 }
354 }
355
356 if (gl->gl_state == gh->gh_state)
357 return true;
358 if (gh->gh_flags & GL_EXACT)
359 return false;
360 if (gl->gl_state == LM_ST_EXCLUSIVE) {
361 return gh->gh_state == LM_ST_SHARED ||
362 gh->gh_state == LM_ST_DEFERRED;
363 }
364 if (gh->gh_flags & LM_FLAG_ANY)
365 return gl->gl_state != LM_ST_UNLOCKED;
366 return false;
367}
368
369static void gfs2_holder_wake(struct gfs2_holder *gh)
370{
371 clear_bit(HIF_WAIT, &gh->gh_iflags);
372 smp_mb__after_atomic();
373 wake_up_bit(&gh->gh_iflags, HIF_WAIT);
374 if (gh->gh_flags & GL_ASYNC) {
375 struct gfs2_sbd *sdp = gh->gh_gl->gl_name.ln_sbd;
376
377 wake_up(&sdp->sd_async_glock_wait);
378 }
379}
380
381
382
383
384
385
386
387static void do_error(struct gfs2_glock *gl, const int ret)
388{
389 struct gfs2_holder *gh, *tmp;
390
391 list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
392 if (!test_bit(HIF_WAIT, &gh->gh_iflags))
393 continue;
394 if (ret & LM_OUT_ERROR)
395 gh->gh_error = -EIO;
396 else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
397 gh->gh_error = GLR_TRYFAILED;
398 else
399 continue;
400 list_del_init(&gh->gh_list);
401 trace_gfs2_glock_queue(gh, 0);
402 gfs2_holder_wake(gh);
403 }
404}
405
406
407
408
409
410
411static void demote_incompat_holders(struct gfs2_glock *gl,
412 struct gfs2_holder *new_gh)
413{
414 struct gfs2_holder *gh, *tmp;
415
416
417
418
419
420
421 list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
422
423
424
425
426 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
427 return;
428 if (test_bit(HIF_MAY_DEMOTE, &gh->gh_iflags) &&
429 !may_grant(gl, new_gh, gh)) {
430
431
432
433
434
435 __gfs2_glock_dq(gh);
436 }
437 }
438}
439
440
441
442
443
444
445static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl)
446{
447 struct gfs2_holder *gh;
448
449 if (!list_empty(&gl->gl_holders)) {
450 gh = list_first_entry(&gl->gl_holders, struct gfs2_holder,
451 gh_list);
452 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
453 return gh;
454 }
455 return NULL;
456}
457
458
459
460
461
462
463
464static inline struct gfs2_holder *
465find_first_strong_holder(struct gfs2_glock *gl)
466{
467 struct gfs2_holder *gh;
468
469 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
470 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
471 return NULL;
472 if (!test_bit(HIF_MAY_DEMOTE, &gh->gh_iflags))
473 return gh;
474 }
475 return NULL;
476}
477
478
479
480
481
482
483
484
485int gfs2_instantiate(struct gfs2_holder *gh)
486{
487 struct gfs2_glock *gl = gh->gh_gl;
488 const struct gfs2_glock_operations *glops = gl->gl_ops;
489 int ret;
490
491again:
492 if (!test_bit(GLF_INSTANTIATE_NEEDED, &gl->gl_flags))
493 return 0;
494
495
496
497
498
499 if (test_and_set_bit(GLF_INSTANTIATE_IN_PROG, &gl->gl_flags)) {
500 wait_on_bit(&gl->gl_flags, GLF_INSTANTIATE_IN_PROG,
501 TASK_UNINTERRUPTIBLE);
502
503
504
505
506
507
508
509 goto again;
510 }
511
512 ret = glops->go_instantiate(gh);
513 if (!ret)
514 clear_bit(GLF_INSTANTIATE_NEEDED, &gl->gl_flags);
515 clear_and_wake_up_bit(GLF_INSTANTIATE_IN_PROG, &gl->gl_flags);
516 return ret;
517}
518
519
520
521
522
523
524
525
526
527static int do_promote(struct gfs2_glock *gl)
528__releases(&gl->gl_lockref.lock)
529__acquires(&gl->gl_lockref.lock)
530{
531 struct gfs2_holder *gh, *tmp, *first_gh;
532 bool incompat_holders_demoted = false;
533 bool lock_released;
534 int ret;
535
536restart:
537 first_gh = find_first_strong_holder(gl);
538 list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
539 lock_released = false;
540 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
541 continue;
542 if (!may_grant(gl, first_gh, gh)) {
543
544
545
546
547
548 if (gh->gh_list.prev == &gl->gl_holders)
549 return 1;
550 do_error(gl, 0);
551 break;
552 }
553 if (!incompat_holders_demoted) {
554 demote_incompat_holders(gl, first_gh);
555 incompat_holders_demoted = true;
556 first_gh = gh;
557 }
558 if (test_bit(GLF_INSTANTIATE_NEEDED, &gl->gl_flags) &&
559 !(gh->gh_flags & GL_SKIP) && gl->gl_ops->go_instantiate) {
560 lock_released = true;
561 spin_unlock(&gl->gl_lockref.lock);
562 ret = gfs2_instantiate(gh);
563 spin_lock(&gl->gl_lockref.lock);
564 if (ret) {
565 if (ret == 1)
566 return 2;
567 gh->gh_error = ret;
568 list_del_init(&gh->gh_list);
569 trace_gfs2_glock_queue(gh, 0);
570 gfs2_holder_wake(gh);
571 goto restart;
572 }
573 }
574 set_bit(HIF_HOLDER, &gh->gh_iflags);
575 trace_gfs2_promote(gh);
576 gfs2_holder_wake(gh);
577
578
579
580
581
582 if (lock_released)
583 goto restart;
584 }
585 return 0;
586}
587
588
589
590
591
592
593static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl)
594{
595 struct gfs2_holder *gh;
596
597 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
598 if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
599 return gh;
600 }
601 return NULL;
602}
603
604
605
606
607
608
609
610static void state_change(struct gfs2_glock *gl, unsigned int new_state)
611{
612 int held1, held2;
613
614 held1 = (gl->gl_state != LM_ST_UNLOCKED);
615 held2 = (new_state != LM_ST_UNLOCKED);
616
617 if (held1 != held2) {
618 GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
619 if (held2)
620 gl->gl_lockref.count++;
621 else
622 gl->gl_lockref.count--;
623 }
624 if (new_state != gl->gl_target)
625
626 gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR,
627 GL_GLOCK_MIN_HOLD);
628 gl->gl_state = new_state;
629 gl->gl_tchange = jiffies;
630}
631
632static void gfs2_set_demote(struct gfs2_glock *gl)
633{
634 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
635
636 set_bit(GLF_DEMOTE, &gl->gl_flags);
637 smp_mb();
638 wake_up(&sdp->sd_async_glock_wait);
639}
640
641static void gfs2_demote_wake(struct gfs2_glock *gl)
642{
643 gl->gl_demote_state = LM_ST_EXCLUSIVE;
644 clear_bit(GLF_DEMOTE, &gl->gl_flags);
645 smp_mb__after_atomic();
646 wake_up_bit(&gl->gl_flags, GLF_DEMOTE);
647}
648
649
650
651
652
653
654
655
656static void finish_xmote(struct gfs2_glock *gl, unsigned int ret)
657{
658 const struct gfs2_glock_operations *glops = gl->gl_ops;
659 struct gfs2_holder *gh;
660 unsigned state = ret & LM_OUT_ST_MASK;
661 int rv;
662
663 spin_lock(&gl->gl_lockref.lock);
664 trace_gfs2_glock_state_change(gl, state);
665 state_change(gl, state);
666 gh = find_first_waiter(gl);
667
668
669 if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
670 state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED)
671 gl->gl_target = LM_ST_UNLOCKED;
672
673
674 if (unlikely(state != gl->gl_target)) {
675 if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) {
676
677 if (ret & LM_OUT_CANCELED) {
678 if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0)
679 list_move_tail(&gh->gh_list, &gl->gl_holders);
680 gh = find_first_waiter(gl);
681 gl->gl_target = gh->gh_state;
682 goto retry;
683 }
684
685 if ((ret & LM_OUT_ERROR) ||
686 (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
687 gl->gl_target = gl->gl_state;
688 do_error(gl, ret);
689 goto out;
690 }
691 }
692 switch(state) {
693
694 case LM_ST_UNLOCKED:
695retry:
696 do_xmote(gl, gh, gl->gl_target);
697 break;
698
699 case LM_ST_SHARED:
700 case LM_ST_DEFERRED:
701 do_xmote(gl, gh, LM_ST_UNLOCKED);
702 break;
703 default:
704 fs_err(gl->gl_name.ln_sbd, "wanted %u got %u\n",
705 gl->gl_target, state);
706 GLOCK_BUG_ON(gl, 1);
707 }
708 spin_unlock(&gl->gl_lockref.lock);
709 return;
710 }
711
712
713 if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags))
714 gfs2_demote_wake(gl);
715 if (state != LM_ST_UNLOCKED) {
716 if (glops->go_xmote_bh) {
717 spin_unlock(&gl->gl_lockref.lock);
718 rv = glops->go_xmote_bh(gl);
719 spin_lock(&gl->gl_lockref.lock);
720 if (rv) {
721 do_error(gl, rv);
722 goto out;
723 }
724 }
725 rv = do_promote(gl);
726 if (rv == 2)
727 goto out_locked;
728 }
729out:
730 clear_bit(GLF_LOCK, &gl->gl_flags);
731out_locked:
732 spin_unlock(&gl->gl_lockref.lock);
733}
734
735static bool is_system_glock(struct gfs2_glock *gl)
736{
737 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
738 struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
739
740 if (gl == m_ip->i_gl)
741 return true;
742 return false;
743}
744
745
746
747
748
749
750
751
752
753static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target)
754__releases(&gl->gl_lockref.lock)
755__acquires(&gl->gl_lockref.lock)
756{
757 const struct gfs2_glock_operations *glops = gl->gl_ops;
758 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
759 unsigned int lck_flags = (unsigned int)(gh ? gh->gh_flags : 0);
760 int ret;
761
762 if (target != LM_ST_UNLOCKED && glock_blocked_by_withdraw(gl) &&
763 gh && !(gh->gh_flags & LM_FLAG_NOEXP))
764 return;
765 lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP |
766 LM_FLAG_PRIORITY);
767 GLOCK_BUG_ON(gl, gl->gl_state == target);
768 GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target);
769 if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) &&
770 glops->go_inval) {
771
772
773
774
775
776 if (test_and_set_bit(GLF_INVALIDATE_IN_PROGRESS,
777 &gl->gl_flags))
778 return;
779 do_error(gl, 0);
780 }
781 gl->gl_req = target;
782 set_bit(GLF_BLOCKING, &gl->gl_flags);
783 if ((gl->gl_req == LM_ST_UNLOCKED) ||
784 (gl->gl_state == LM_ST_EXCLUSIVE) ||
785 (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB)))
786 clear_bit(GLF_BLOCKING, &gl->gl_flags);
787 spin_unlock(&gl->gl_lockref.lock);
788 if (glops->go_sync) {
789 ret = glops->go_sync(gl);
790
791
792
793
794 if (ret) {
795 if (cmpxchg(&sdp->sd_log_error, 0, ret)) {
796 fs_err(sdp, "Error %d syncing glock \n", ret);
797 gfs2_dump_glock(NULL, gl, true);
798 }
799 goto skip_inval;
800 }
801 }
802 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) {
803
804
805
806
807
808
809
810 if ((atomic_read(&gl->gl_ail_count) != 0) &&
811 (!cmpxchg(&sdp->sd_log_error, 0, -EIO))) {
812 gfs2_glock_assert_warn(gl,
813 !atomic_read(&gl->gl_ail_count));
814 gfs2_dump_glock(NULL, gl, true);
815 }
816 glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA);
817 clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
818 }
819
820skip_inval:
821 gfs2_glock_hold(gl);
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843 if (unlikely(sdp->sd_log_error && !gfs2_withdrawn(sdp)))
844 gfs2_withdraw_delayed(sdp);
845 if (glock_blocked_by_withdraw(gl) &&
846 (target != LM_ST_UNLOCKED ||
847 test_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags))) {
848 if (!is_system_glock(gl)) {
849 gfs2_glock_queue_work(gl, GL_GLOCK_DFT_HOLD);
850 goto out;
851 } else {
852 clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
853 }
854 }
855
856 if (sdp->sd_lockstruct.ls_ops->lm_lock) {
857
858 ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags);
859 if (ret == -EINVAL && gl->gl_target == LM_ST_UNLOCKED &&
860 target == LM_ST_UNLOCKED &&
861 test_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags)) {
862 finish_xmote(gl, target);
863 gfs2_glock_queue_work(gl, 0);
864 } else if (ret) {
865 fs_err(sdp, "lm_lock ret %d\n", ret);
866 GLOCK_BUG_ON(gl, !gfs2_withdrawn(sdp));
867 }
868 } else {
869 finish_xmote(gl, target);
870 gfs2_glock_queue_work(gl, 0);
871 }
872out:
873 spin_lock(&gl->gl_lockref.lock);
874}
875
876
877
878
879
880
881
882
883static void run_queue(struct gfs2_glock *gl, const int nonblock)
884__releases(&gl->gl_lockref.lock)
885__acquires(&gl->gl_lockref.lock)
886{
887 struct gfs2_holder *gh = NULL;
888 int ret;
889
890 if (test_and_set_bit(GLF_LOCK, &gl->gl_flags))
891 return;
892
893 GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags));
894
895 if (test_bit(GLF_DEMOTE, &gl->gl_flags) &&
896 gl->gl_demote_state != gl->gl_state) {
897 if (find_first_holder(gl))
898 goto out_unlock;
899 if (nonblock)
900 goto out_sched;
901 set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
902 GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE);
903 gl->gl_target = gl->gl_demote_state;
904 } else {
905 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
906 gfs2_demote_wake(gl);
907 ret = do_promote(gl);
908 if (ret == 0)
909 goto out_unlock;
910 if (ret == 2)
911 goto out;
912 gh = find_first_waiter(gl);
913 gl->gl_target = gh->gh_state;
914 if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)))
915 do_error(gl, 0);
916 }
917 do_xmote(gl, gh, gl->gl_target);
918out:
919 return;
920
921out_sched:
922 clear_bit(GLF_LOCK, &gl->gl_flags);
923 smp_mb__after_atomic();
924 gl->gl_lockref.count++;
925 __gfs2_glock_queue_work(gl, 0);
926 return;
927
928out_unlock:
929 clear_bit(GLF_LOCK, &gl->gl_flags);
930 smp_mb__after_atomic();
931 return;
932}
933
934void gfs2_inode_remember_delete(struct gfs2_glock *gl, u64 generation)
935{
936 struct gfs2_inode_lvb *ri = (void *)gl->gl_lksb.sb_lvbptr;
937
938 if (ri->ri_magic == 0)
939 ri->ri_magic = cpu_to_be32(GFS2_MAGIC);
940 if (ri->ri_magic == cpu_to_be32(GFS2_MAGIC))
941 ri->ri_generation_deleted = cpu_to_be64(generation);
942}
943
944bool gfs2_inode_already_deleted(struct gfs2_glock *gl, u64 generation)
945{
946 struct gfs2_inode_lvb *ri = (void *)gl->gl_lksb.sb_lvbptr;
947
948 if (ri->ri_magic != cpu_to_be32(GFS2_MAGIC))
949 return false;
950 return generation <= be64_to_cpu(ri->ri_generation_deleted);
951}
952
953static void gfs2_glock_poke(struct gfs2_glock *gl)
954{
955 int flags = LM_FLAG_TRY_1CB | LM_FLAG_ANY | GL_SKIP;
956 struct gfs2_holder gh;
957 int error;
958
959 __gfs2_holder_init(gl, LM_ST_SHARED, flags, &gh, _RET_IP_);
960 error = gfs2_glock_nq(&gh);
961 if (!error)
962 gfs2_glock_dq(&gh);
963 gfs2_holder_uninit(&gh);
964}
965
966static bool gfs2_try_evict(struct gfs2_glock *gl)
967{
968 struct gfs2_inode *ip;
969 bool evicted = false;
970
971
972
973
974
975
976
977
978
979
980
981 spin_lock(&gl->gl_lockref.lock);
982 ip = gl->gl_object;
983 if (ip && !igrab(&ip->i_inode))
984 ip = NULL;
985 spin_unlock(&gl->gl_lockref.lock);
986 if (ip) {
987 struct gfs2_glock *inode_gl = NULL;
988
989 gl->gl_no_formal_ino = ip->i_no_formal_ino;
990 set_bit(GIF_DEFERRED_DELETE, &ip->i_flags);
991 d_prune_aliases(&ip->i_inode);
992 iput(&ip->i_inode);
993
994
995 spin_lock(&gl->gl_lockref.lock);
996 ip = gl->gl_object;
997 if (ip) {
998 inode_gl = ip->i_gl;
999 lockref_get(&inode_gl->gl_lockref);
1000 clear_bit(GIF_DEFERRED_DELETE, &ip->i_flags);
1001 }
1002 spin_unlock(&gl->gl_lockref.lock);
1003 if (inode_gl) {
1004 gfs2_glock_poke(inode_gl);
1005 gfs2_glock_put(inode_gl);
1006 }
1007 evicted = !ip;
1008 }
1009 return evicted;
1010}
1011
1012static void delete_work_func(struct work_struct *work)
1013{
1014 struct delayed_work *dwork = to_delayed_work(work);
1015 struct gfs2_glock *gl = container_of(dwork, struct gfs2_glock, gl_delete);
1016 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
1017 struct inode *inode;
1018 u64 no_addr = gl->gl_name.ln_number;
1019
1020 spin_lock(&gl->gl_lockref.lock);
1021 clear_bit(GLF_PENDING_DELETE, &gl->gl_flags);
1022 spin_unlock(&gl->gl_lockref.lock);
1023
1024 if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042 if (gfs2_try_evict(gl)) {
1043 if (gfs2_queue_delete_work(gl, 5 * HZ))
1044 return;
1045 }
1046 goto out;
1047 }
1048
1049 inode = gfs2_lookup_by_inum(sdp, no_addr, gl->gl_no_formal_ino,
1050 GFS2_BLKST_UNLINKED);
1051 if (!IS_ERR_OR_NULL(inode)) {
1052 d_prune_aliases(inode);
1053 iput(inode);
1054 }
1055out:
1056 gfs2_glock_put(gl);
1057}
1058
1059static void glock_work_func(struct work_struct *work)
1060{
1061 unsigned long delay = 0;
1062 struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work);
1063 unsigned int drop_refs = 1;
1064
1065 if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) {
1066 finish_xmote(gl, gl->gl_reply);
1067 drop_refs++;
1068 }
1069 spin_lock(&gl->gl_lockref.lock);
1070 if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
1071 gl->gl_state != LM_ST_UNLOCKED &&
1072 gl->gl_demote_state != LM_ST_EXCLUSIVE) {
1073 unsigned long holdtime, now = jiffies;
1074
1075 holdtime = gl->gl_tchange + gl->gl_hold_time;
1076 if (time_before(now, holdtime))
1077 delay = holdtime - now;
1078
1079 if (!delay) {
1080 clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
1081 gfs2_set_demote(gl);
1082 }
1083 }
1084 run_queue(gl, 0);
1085 if (delay) {
1086
1087 drop_refs--;
1088 if (gl->gl_name.ln_type != LM_TYPE_INODE)
1089 delay = 0;
1090 __gfs2_glock_queue_work(gl, delay);
1091 }
1092
1093
1094
1095
1096
1097
1098 gl->gl_lockref.count -= drop_refs;
1099 if (!gl->gl_lockref.count) {
1100 __gfs2_glock_put(gl);
1101 return;
1102 }
1103 spin_unlock(&gl->gl_lockref.lock);
1104}
1105
1106static struct gfs2_glock *find_insert_glock(struct lm_lockname *name,
1107 struct gfs2_glock *new)
1108{
1109 struct wait_glock_queue wait;
1110 wait_queue_head_t *wq = glock_waitqueue(name);
1111 struct gfs2_glock *gl;
1112
1113 wait.name = name;
1114 init_wait(&wait.wait);
1115 wait.wait.func = glock_wake_function;
1116
1117again:
1118 prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
1119 rcu_read_lock();
1120 if (new) {
1121 gl = rhashtable_lookup_get_insert_fast(&gl_hash_table,
1122 &new->gl_node, ht_parms);
1123 if (IS_ERR(gl))
1124 goto out;
1125 } else {
1126 gl = rhashtable_lookup_fast(&gl_hash_table,
1127 name, ht_parms);
1128 }
1129 if (gl && !lockref_get_not_dead(&gl->gl_lockref)) {
1130 rcu_read_unlock();
1131 schedule();
1132 goto again;
1133 }
1134out:
1135 rcu_read_unlock();
1136 finish_wait(wq, &wait.wait);
1137 return gl;
1138}
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
1154 const struct gfs2_glock_operations *glops, int create,
1155 struct gfs2_glock **glp)
1156{
1157 struct super_block *s = sdp->sd_vfs;
1158 struct lm_lockname name = { .ln_number = number,
1159 .ln_type = glops->go_type,
1160 .ln_sbd = sdp };
1161 struct gfs2_glock *gl, *tmp;
1162 struct address_space *mapping;
1163 struct kmem_cache *cachep;
1164 int ret = 0;
1165
1166 gl = find_insert_glock(&name, NULL);
1167 if (gl) {
1168 *glp = gl;
1169 return 0;
1170 }
1171 if (!create)
1172 return -ENOENT;
1173
1174 if (glops->go_flags & GLOF_ASPACE)
1175 cachep = gfs2_glock_aspace_cachep;
1176 else
1177 cachep = gfs2_glock_cachep;
1178 gl = kmem_cache_alloc(cachep, GFP_NOFS);
1179 if (!gl)
1180 return -ENOMEM;
1181
1182 memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb));
1183
1184 if (glops->go_flags & GLOF_LVB) {
1185 gl->gl_lksb.sb_lvbptr = kzalloc(GDLM_LVB_SIZE, GFP_NOFS);
1186 if (!gl->gl_lksb.sb_lvbptr) {
1187 kmem_cache_free(cachep, gl);
1188 return -ENOMEM;
1189 }
1190 }
1191
1192 atomic_inc(&sdp->sd_glock_disposal);
1193 gl->gl_node.next = NULL;
1194 gl->gl_flags = glops->go_instantiate ? BIT(GLF_INSTANTIATE_NEEDED) : 0;
1195 gl->gl_name = name;
1196 lockdep_set_subclass(&gl->gl_lockref.lock, glops->go_subclass);
1197 gl->gl_lockref.count = 1;
1198 gl->gl_state = LM_ST_UNLOCKED;
1199 gl->gl_target = LM_ST_UNLOCKED;
1200 gl->gl_demote_state = LM_ST_EXCLUSIVE;
1201 gl->gl_ops = glops;
1202 gl->gl_dstamp = 0;
1203 preempt_disable();
1204
1205 gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type];
1206 preempt_enable();
1207 gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0;
1208 gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0;
1209 gl->gl_tchange = jiffies;
1210 gl->gl_object = NULL;
1211 gl->gl_hold_time = GL_GLOCK_DFT_HOLD;
1212 INIT_DELAYED_WORK(&gl->gl_work, glock_work_func);
1213 if (gl->gl_name.ln_type == LM_TYPE_IOPEN)
1214 INIT_DELAYED_WORK(&gl->gl_delete, delete_work_func);
1215
1216 mapping = gfs2_glock2aspace(gl);
1217 if (mapping) {
1218 mapping->a_ops = &gfs2_meta_aops;
1219 mapping->host = s->s_bdev->bd_inode;
1220 mapping->flags = 0;
1221 mapping_set_gfp_mask(mapping, GFP_NOFS);
1222 mapping->private_data = NULL;
1223 mapping->writeback_index = 0;
1224 }
1225
1226 tmp = find_insert_glock(&name, gl);
1227 if (!tmp) {
1228 *glp = gl;
1229 goto out;
1230 }
1231 if (IS_ERR(tmp)) {
1232 ret = PTR_ERR(tmp);
1233 goto out_free;
1234 }
1235 *glp = tmp;
1236
1237out_free:
1238 kfree(gl->gl_lksb.sb_lvbptr);
1239 kmem_cache_free(cachep, gl);
1240 if (atomic_dec_and_test(&sdp->sd_glock_disposal))
1241 wake_up(&sdp->sd_glock_wait);
1242
1243out:
1244 return ret;
1245}
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256void __gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, u16 flags,
1257 struct gfs2_holder *gh, unsigned long ip)
1258{
1259 INIT_LIST_HEAD(&gh->gh_list);
1260 gh->gh_gl = gl;
1261 gh->gh_ip = ip;
1262 gh->gh_owner_pid = get_pid(task_pid(current));
1263 gh->gh_state = state;
1264 gh->gh_flags = flags;
1265 gh->gh_error = 0;
1266 gh->gh_iflags = 0;
1267 gfs2_glock_hold(gl);
1268}
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280void gfs2_holder_reinit(unsigned int state, u16 flags, struct gfs2_holder *gh)
1281{
1282 gh->gh_state = state;
1283 gh->gh_flags = flags;
1284 gh->gh_iflags = 0;
1285 gh->gh_ip = _RET_IP_;
1286 put_pid(gh->gh_owner_pid);
1287 gh->gh_owner_pid = get_pid(task_pid(current));
1288}
1289
1290
1291
1292
1293
1294
1295
1296void gfs2_holder_uninit(struct gfs2_holder *gh)
1297{
1298 put_pid(gh->gh_owner_pid);
1299 gfs2_glock_put(gh->gh_gl);
1300 gfs2_holder_mark_uninitialized(gh);
1301 gh->gh_ip = 0;
1302}
1303
1304static void gfs2_glock_update_hold_time(struct gfs2_glock *gl,
1305 unsigned long start_time)
1306{
1307
1308 if (time_after(jiffies, start_time + HZ)) {
1309
1310 gl->gl_hold_time = min(gl->gl_hold_time + GL_GLOCK_HOLD_INCR,
1311 GL_GLOCK_MAX_HOLD);
1312 }
1313}
1314
1315
1316
1317
1318
1319
1320
1321
1322int gfs2_glock_wait(struct gfs2_holder *gh)
1323{
1324 unsigned long start_time = jiffies;
1325
1326 might_sleep();
1327 wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE);
1328 gfs2_glock_update_hold_time(gh->gh_gl, start_time);
1329 return gh->gh_error;
1330}
1331
1332static int glocks_pending(unsigned int num_gh, struct gfs2_holder *ghs)
1333{
1334 int i;
1335
1336 for (i = 0; i < num_gh; i++)
1337 if (test_bit(HIF_WAIT, &ghs[i].gh_iflags))
1338 return 1;
1339 return 0;
1340}
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs)
1353{
1354 struct gfs2_sbd *sdp = ghs[0].gh_gl->gl_name.ln_sbd;
1355 int i, ret = 0, timeout = 0;
1356 unsigned long start_time = jiffies;
1357 bool keep_waiting;
1358
1359 might_sleep();
1360
1361
1362
1363
1364 for (i = 0; i < num_gh; i++)
1365 timeout += ghs[i].gh_gl->gl_hold_time << 1;
1366
1367wait_for_dlm:
1368 if (!wait_event_timeout(sdp->sd_async_glock_wait,
1369 !glocks_pending(num_gh, ghs), timeout))
1370 ret = -ESTALE;
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386 keep_waiting = false;
1387 for (i = 0; i < num_gh; i++) {
1388
1389 if (!gfs2_holder_queued(&ghs[i]))
1390 continue;
1391
1392 if (test_bit(HIF_WAIT, &ghs[i].gh_iflags)) {
1393 keep_waiting = true;
1394 continue;
1395 }
1396
1397 if (test_bit(HIF_HOLDER, &ghs[i].gh_iflags)) {
1398 if (ret == -ESTALE)
1399 gfs2_glock_dq(&ghs[i]);
1400 else
1401 gfs2_glock_update_hold_time(ghs[i].gh_gl,
1402 start_time);
1403 }
1404 if (!ret)
1405 ret = ghs[i].gh_error;
1406 }
1407
1408 if (keep_waiting)
1409 goto wait_for_dlm;
1410
1411
1412
1413
1414 return ret;
1415}
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428static void handle_callback(struct gfs2_glock *gl, unsigned int state,
1429 unsigned long delay, bool remote)
1430{
1431 if (delay)
1432 set_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
1433 else
1434 gfs2_set_demote(gl);
1435 if (gl->gl_demote_state == LM_ST_EXCLUSIVE) {
1436 gl->gl_demote_state = state;
1437 gl->gl_demote_time = jiffies;
1438 } else if (gl->gl_demote_state != LM_ST_UNLOCKED &&
1439 gl->gl_demote_state != state) {
1440 gl->gl_demote_state = LM_ST_UNLOCKED;
1441 }
1442 if (gl->gl_ops->go_callback)
1443 gl->gl_ops->go_callback(gl, remote);
1444 trace_gfs2_demote_rq(gl, remote);
1445}
1446
1447void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
1448{
1449 struct va_format vaf;
1450 va_list args;
1451
1452 va_start(args, fmt);
1453
1454 if (seq) {
1455 seq_vprintf(seq, fmt, args);
1456 } else {
1457 vaf.fmt = fmt;
1458 vaf.va = &args;
1459
1460 pr_err("%pV", &vaf);
1461 }
1462
1463 va_end(args);
1464}
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476static inline void add_to_queue(struct gfs2_holder *gh)
1477__releases(&gl->gl_lockref.lock)
1478__acquires(&gl->gl_lockref.lock)
1479{
1480 struct gfs2_glock *gl = gh->gh_gl;
1481 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
1482 struct list_head *insert_pt = NULL;
1483 struct gfs2_holder *gh2;
1484 int try_futile = 0;
1485
1486 GLOCK_BUG_ON(gl, gh->gh_owner_pid == NULL);
1487 if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
1488 GLOCK_BUG_ON(gl, true);
1489
1490 if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
1491 if (test_bit(GLF_LOCK, &gl->gl_flags)) {
1492 struct gfs2_holder *first_gh;
1493
1494 first_gh = find_first_strong_holder(gl);
1495 try_futile = !may_grant(gl, first_gh, gh);
1496 }
1497 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
1498 goto fail;
1499 }
1500
1501 list_for_each_entry(gh2, &gl->gl_holders, gh_list) {
1502 if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid &&
1503 (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK) &&
1504 !test_bit(HIF_MAY_DEMOTE, &gh2->gh_iflags)))
1505 goto trap_recursive;
1506 if (try_futile &&
1507 !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
1508fail:
1509 gh->gh_error = GLR_TRYFAILED;
1510 gfs2_holder_wake(gh);
1511 return;
1512 }
1513 if (test_bit(HIF_HOLDER, &gh2->gh_iflags))
1514 continue;
1515 if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt))
1516 insert_pt = &gh2->gh_list;
1517 }
1518 trace_gfs2_glock_queue(gh, 1);
1519 gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT);
1520 gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT);
1521 if (likely(insert_pt == NULL)) {
1522 list_add_tail(&gh->gh_list, &gl->gl_holders);
1523 if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY))
1524 goto do_cancel;
1525 return;
1526 }
1527 list_add_tail(&gh->gh_list, insert_pt);
1528do_cancel:
1529 gh = list_first_entry(&gl->gl_holders, struct gfs2_holder, gh_list);
1530 if (!(gh->gh_flags & LM_FLAG_PRIORITY)) {
1531 spin_unlock(&gl->gl_lockref.lock);
1532 if (sdp->sd_lockstruct.ls_ops->lm_cancel)
1533 sdp->sd_lockstruct.ls_ops->lm_cancel(gl);
1534 spin_lock(&gl->gl_lockref.lock);
1535 }
1536 return;
1537
1538trap_recursive:
1539 fs_err(sdp, "original: %pSR\n", (void *)gh2->gh_ip);
1540 fs_err(sdp, "pid: %d\n", pid_nr(gh2->gh_owner_pid));
1541 fs_err(sdp, "lock type: %d req lock state : %d\n",
1542 gh2->gh_gl->gl_name.ln_type, gh2->gh_state);
1543 fs_err(sdp, "new: %pSR\n", (void *)gh->gh_ip);
1544 fs_err(sdp, "pid: %d\n", pid_nr(gh->gh_owner_pid));
1545 fs_err(sdp, "lock type: %d req lock state : %d\n",
1546 gh->gh_gl->gl_name.ln_type, gh->gh_state);
1547 gfs2_dump_glock(NULL, gl, true);
1548 BUG();
1549}
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560int gfs2_glock_nq(struct gfs2_holder *gh)
1561{
1562 struct gfs2_glock *gl = gh->gh_gl;
1563 int error = 0;
1564
1565 if (glock_blocked_by_withdraw(gl) && !(gh->gh_flags & LM_FLAG_NOEXP))
1566 return -EIO;
1567
1568 if (test_bit(GLF_LRU, &gl->gl_flags))
1569 gfs2_glock_remove_from_lru(gl);
1570
1571 spin_lock(&gl->gl_lockref.lock);
1572 add_to_queue(gh);
1573 if (unlikely((LM_FLAG_NOEXP & gh->gh_flags) &&
1574 test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))) {
1575 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
1576 gl->gl_lockref.count++;
1577 __gfs2_glock_queue_work(gl, 0);
1578 }
1579 run_queue(gl, 1);
1580 spin_unlock(&gl->gl_lockref.lock);
1581
1582 if (!(gh->gh_flags & GL_ASYNC))
1583 error = gfs2_glock_wait(gh);
1584
1585 return error;
1586}
1587
1588
1589
1590
1591
1592
1593
1594
1595int gfs2_glock_poll(struct gfs2_holder *gh)
1596{
1597 return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1;
1598}
1599
1600static inline bool needs_demote(struct gfs2_glock *gl)
1601{
1602 return (test_bit(GLF_DEMOTE, &gl->gl_flags) ||
1603 test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags));
1604}
1605
1606static void __gfs2_glock_dq(struct gfs2_holder *gh)
1607{
1608 struct gfs2_glock *gl = gh->gh_gl;
1609 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
1610 unsigned delay = 0;
1611 int fast_path = 0;
1612
1613
1614
1615
1616
1617
1618
1619 while (gh) {
1620
1621
1622
1623
1624
1625
1626
1627 if (test_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags) &&
1628 glock_blocked_by_withdraw(gl) &&
1629 gh->gh_gl != sdp->sd_jinode_gl) {
1630 sdp->sd_glock_dqs_held++;
1631 spin_unlock(&gl->gl_lockref.lock);
1632 might_sleep();
1633 wait_on_bit(&sdp->sd_flags, SDF_WITHDRAW_RECOVERY,
1634 TASK_UNINTERRUPTIBLE);
1635 spin_lock(&gl->gl_lockref.lock);
1636 }
1637
1638
1639
1640
1641
1642
1643 if (gh->gh_flags & GL_NOCACHE)
1644 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
1645
1646 list_del_init(&gh->gh_list);
1647 clear_bit(HIF_HOLDER, &gh->gh_iflags);
1648 trace_gfs2_glock_queue(gh, 0);
1649
1650
1651
1652
1653
1654 if (!needs_demote(gl)) {
1655 if (list_empty(&gl->gl_holders))
1656 fast_path = 1;
1657 break;
1658 }
1659
1660
1661
1662
1663 if (find_first_strong_holder(gl))
1664 break;
1665
1666
1667
1668
1669
1670
1671 gh = find_first_holder(gl);
1672 }
1673
1674 if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl))
1675 gfs2_glock_add_to_lru(gl);
1676
1677 if (unlikely(!fast_path)) {
1678 gl->gl_lockref.count++;
1679 if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
1680 !test_bit(GLF_DEMOTE, &gl->gl_flags) &&
1681 gl->gl_name.ln_type == LM_TYPE_INODE)
1682 delay = gl->gl_hold_time;
1683 __gfs2_glock_queue_work(gl, delay);
1684 }
1685}
1686
1687
1688
1689
1690
1691
1692void gfs2_glock_dq(struct gfs2_holder *gh)
1693{
1694 struct gfs2_glock *gl = gh->gh_gl;
1695
1696 spin_lock(&gl->gl_lockref.lock);
1697 __gfs2_glock_dq(gh);
1698 spin_unlock(&gl->gl_lockref.lock);
1699}
1700
1701void gfs2_glock_dq_wait(struct gfs2_holder *gh)
1702{
1703 struct gfs2_glock *gl = gh->gh_gl;
1704 gfs2_glock_dq(gh);
1705 might_sleep();
1706 wait_on_bit(&gl->gl_flags, GLF_DEMOTE, TASK_UNINTERRUPTIBLE);
1707}
1708
1709
1710
1711
1712
1713
1714
1715void gfs2_glock_dq_uninit(struct gfs2_holder *gh)
1716{
1717 gfs2_glock_dq(gh);
1718 gfs2_holder_uninit(gh);
1719}
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
1734 const struct gfs2_glock_operations *glops,
1735 unsigned int state, u16 flags, struct gfs2_holder *gh)
1736{
1737 struct gfs2_glock *gl;
1738 int error;
1739
1740 error = gfs2_glock_get(sdp, number, glops, CREATE, &gl);
1741 if (!error) {
1742 error = gfs2_glock_nq_init(gl, state, flags, gh);
1743 gfs2_glock_put(gl);
1744 }
1745
1746 return error;
1747}
1748
1749
1750
1751
1752
1753
1754
1755
1756static int glock_compare(const void *arg_a, const void *arg_b)
1757{
1758 const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a;
1759 const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b;
1760 const struct lm_lockname *a = &gh_a->gh_gl->gl_name;
1761 const struct lm_lockname *b = &gh_b->gh_gl->gl_name;
1762
1763 if (a->ln_number > b->ln_number)
1764 return 1;
1765 if (a->ln_number < b->ln_number)
1766 return -1;
1767 BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type);
1768 return 0;
1769}
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs,
1782 struct gfs2_holder **p)
1783{
1784 unsigned int x;
1785 int error = 0;
1786
1787 for (x = 0; x < num_gh; x++)
1788 p[x] = &ghs[x];
1789
1790 sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL);
1791
1792 for (x = 0; x < num_gh; x++) {
1793 p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1794
1795 error = gfs2_glock_nq(p[x]);
1796 if (error) {
1797 while (x--)
1798 gfs2_glock_dq(p[x]);
1799 break;
1800 }
1801 }
1802
1803 return error;
1804}
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1817{
1818 struct gfs2_holder *tmp[4];
1819 struct gfs2_holder **pph = tmp;
1820 int error = 0;
1821
1822 switch(num_gh) {
1823 case 0:
1824 return 0;
1825 case 1:
1826 ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
1827 return gfs2_glock_nq(ghs);
1828 default:
1829 if (num_gh <= 4)
1830 break;
1831 pph = kmalloc_array(num_gh, sizeof(struct gfs2_holder *),
1832 GFP_NOFS);
1833 if (!pph)
1834 return -ENOMEM;
1835 }
1836
1837 error = nq_m_sync(num_gh, ghs, pph);
1838
1839 if (pph != tmp)
1840 kfree(pph);
1841
1842 return error;
1843}
1844
1845
1846
1847
1848
1849
1850
1851
1852void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
1853{
1854 while (num_gh--)
1855 gfs2_glock_dq(&ghs[num_gh]);
1856}
1857
1858void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state)
1859{
1860 unsigned long delay = 0;
1861 unsigned long holdtime;
1862 unsigned long now = jiffies;
1863
1864 gfs2_glock_hold(gl);
1865 spin_lock(&gl->gl_lockref.lock);
1866 holdtime = gl->gl_tchange + gl->gl_hold_time;
1867 if (!list_empty(&gl->gl_holders) &&
1868 gl->gl_name.ln_type == LM_TYPE_INODE) {
1869 if (time_before(now, holdtime))
1870 delay = holdtime - now;
1871 if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags))
1872 delay = gl->gl_hold_time;
1873 }
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891 if (!find_first_strong_holder(gl)) {
1892 struct gfs2_holder mock_gh = {
1893 .gh_gl = gl,
1894 .gh_state = (state == LM_ST_UNLOCKED) ?
1895 LM_ST_EXCLUSIVE : state,
1896 .gh_iflags = BIT(HIF_HOLDER)
1897 };
1898
1899 demote_incompat_holders(gl, &mock_gh);
1900 }
1901 handle_callback(gl, state, delay, true);
1902 __gfs2_glock_queue_work(gl, delay);
1903 spin_unlock(&gl->gl_lockref.lock);
1904}
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917static int gfs2_should_freeze(const struct gfs2_glock *gl)
1918{
1919 const struct gfs2_holder *gh;
1920
1921 if (gl->gl_reply & ~LM_OUT_ST_MASK)
1922 return 0;
1923 if (gl->gl_target == LM_ST_UNLOCKED)
1924 return 0;
1925
1926 list_for_each_entry(gh, &gl->gl_holders, gh_list) {
1927 if (test_bit(HIF_HOLDER, &gh->gh_iflags))
1928 continue;
1929 if (LM_FLAG_NOEXP & gh->gh_flags)
1930 return 0;
1931 }
1932
1933 return 1;
1934}
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
1946{
1947 struct lm_lockstruct *ls = &gl->gl_name.ln_sbd->sd_lockstruct;
1948
1949 spin_lock(&gl->gl_lockref.lock);
1950 gl->gl_reply = ret;
1951
1952 if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) {
1953 if (gfs2_should_freeze(gl)) {
1954 set_bit(GLF_FROZEN, &gl->gl_flags);
1955 spin_unlock(&gl->gl_lockref.lock);
1956 return;
1957 }
1958 }
1959
1960 gl->gl_lockref.count++;
1961 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
1962 __gfs2_glock_queue_work(gl, 0);
1963 spin_unlock(&gl->gl_lockref.lock);
1964}
1965
1966static int glock_cmp(void *priv, const struct list_head *a,
1967 const struct list_head *b)
1968{
1969 struct gfs2_glock *gla, *glb;
1970
1971 gla = list_entry(a, struct gfs2_glock, gl_lru);
1972 glb = list_entry(b, struct gfs2_glock, gl_lru);
1973
1974 if (gla->gl_name.ln_number > glb->gl_name.ln_number)
1975 return 1;
1976 if (gla->gl_name.ln_number < glb->gl_name.ln_number)
1977 return -1;
1978
1979 return 0;
1980}
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996static void gfs2_dispose_glock_lru(struct list_head *list)
1997__releases(&lru_lock)
1998__acquires(&lru_lock)
1999{
2000 struct gfs2_glock *gl;
2001
2002 list_sort(NULL, list, glock_cmp);
2003
2004 while(!list_empty(list)) {
2005 gl = list_first_entry(list, struct gfs2_glock, gl_lru);
2006 list_del_init(&gl->gl_lru);
2007 clear_bit(GLF_LRU, &gl->gl_flags);
2008 if (!spin_trylock(&gl->gl_lockref.lock)) {
2009add_back_to_lru:
2010 list_add(&gl->gl_lru, &lru_list);
2011 set_bit(GLF_LRU, &gl->gl_flags);
2012 atomic_inc(&lru_count);
2013 continue;
2014 }
2015 if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
2016 spin_unlock(&gl->gl_lockref.lock);
2017 goto add_back_to_lru;
2018 }
2019 gl->gl_lockref.count++;
2020 if (demote_ok(gl))
2021 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
2022 WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags));
2023 __gfs2_glock_queue_work(gl, 0);
2024 spin_unlock(&gl->gl_lockref.lock);
2025 cond_resched_lock(&lru_lock);
2026 }
2027}
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038static long gfs2_scan_glock_lru(int nr)
2039{
2040 struct gfs2_glock *gl;
2041 LIST_HEAD(skipped);
2042 LIST_HEAD(dispose);
2043 long freed = 0;
2044
2045 spin_lock(&lru_lock);
2046 while ((nr-- >= 0) && !list_empty(&lru_list)) {
2047 gl = list_first_entry(&lru_list, struct gfs2_glock, gl_lru);
2048
2049
2050 if (!test_bit(GLF_LOCK, &gl->gl_flags)) {
2051 list_move(&gl->gl_lru, &dispose);
2052 atomic_dec(&lru_count);
2053 freed++;
2054 continue;
2055 }
2056
2057 list_move(&gl->gl_lru, &skipped);
2058 }
2059 list_splice(&skipped, &lru_list);
2060 if (!list_empty(&dispose))
2061 gfs2_dispose_glock_lru(&dispose);
2062 spin_unlock(&lru_lock);
2063
2064 return freed;
2065}
2066
2067static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink,
2068 struct shrink_control *sc)
2069{
2070 if (!(sc->gfp_mask & __GFP_FS))
2071 return SHRINK_STOP;
2072 return gfs2_scan_glock_lru(sc->nr_to_scan);
2073}
2074
2075static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink,
2076 struct shrink_control *sc)
2077{
2078 return vfs_pressure_ratio(atomic_read(&lru_count));
2079}
2080
2081static struct shrinker glock_shrinker = {
2082 .seeks = DEFAULT_SEEKS,
2083 .count_objects = gfs2_glock_shrink_count,
2084 .scan_objects = gfs2_glock_shrink_scan,
2085};
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp)
2098{
2099 struct gfs2_glock *gl;
2100 struct rhashtable_iter iter;
2101
2102 rhashtable_walk_enter(&gl_hash_table, &iter);
2103
2104 do {
2105 rhashtable_walk_start(&iter);
2106
2107 while ((gl = rhashtable_walk_next(&iter)) && !IS_ERR(gl)) {
2108 if (gl->gl_name.ln_sbd == sdp)
2109 examiner(gl);
2110 }
2111
2112 rhashtable_walk_stop(&iter);
2113 } while (cond_resched(), gl == ERR_PTR(-EAGAIN));
2114
2115 rhashtable_walk_exit(&iter);
2116}
2117
2118bool gfs2_queue_delete_work(struct gfs2_glock *gl, unsigned long delay)
2119{
2120 bool queued;
2121
2122 spin_lock(&gl->gl_lockref.lock);
2123 queued = queue_delayed_work(gfs2_delete_workqueue,
2124 &gl->gl_delete, delay);
2125 if (queued)
2126 set_bit(GLF_PENDING_DELETE, &gl->gl_flags);
2127 spin_unlock(&gl->gl_lockref.lock);
2128 return queued;
2129}
2130
2131void gfs2_cancel_delete_work(struct gfs2_glock *gl)
2132{
2133 if (cancel_delayed_work(&gl->gl_delete)) {
2134 clear_bit(GLF_PENDING_DELETE, &gl->gl_flags);
2135 gfs2_glock_put(gl);
2136 }
2137}
2138
2139bool gfs2_delete_work_queued(const struct gfs2_glock *gl)
2140{
2141 return test_bit(GLF_PENDING_DELETE, &gl->gl_flags);
2142}
2143
2144static void flush_delete_work(struct gfs2_glock *gl)
2145{
2146 if (gl->gl_name.ln_type == LM_TYPE_IOPEN) {
2147 if (cancel_delayed_work(&gl->gl_delete)) {
2148 queue_delayed_work(gfs2_delete_workqueue,
2149 &gl->gl_delete, 0);
2150 }
2151 }
2152}
2153
2154void gfs2_flush_delete_work(struct gfs2_sbd *sdp)
2155{
2156 glock_hash_walk(flush_delete_work, sdp);
2157 flush_workqueue(gfs2_delete_workqueue);
2158}
2159
2160
2161
2162
2163
2164
2165
2166static void thaw_glock(struct gfs2_glock *gl)
2167{
2168 if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
2169 return;
2170 if (!lockref_get_not_dead(&gl->gl_lockref))
2171 return;
2172 set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
2173 gfs2_glock_queue_work(gl, 0);
2174}
2175
2176
2177
2178
2179
2180
2181
2182static void clear_glock(struct gfs2_glock *gl)
2183{
2184 gfs2_glock_remove_from_lru(gl);
2185
2186 spin_lock(&gl->gl_lockref.lock);
2187 if (!__lockref_is_dead(&gl->gl_lockref)) {
2188 gl->gl_lockref.count++;
2189 if (gl->gl_state != LM_ST_UNLOCKED)
2190 handle_callback(gl, LM_ST_UNLOCKED, 0, false);
2191 __gfs2_glock_queue_work(gl, 0);
2192 }
2193 spin_unlock(&gl->gl_lockref.lock);
2194}
2195
2196
2197
2198
2199
2200
2201
2202void gfs2_glock_thaw(struct gfs2_sbd *sdp)
2203{
2204 glock_hash_walk(thaw_glock, sdp);
2205}
2206
2207static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl, bool fsid)
2208{
2209 spin_lock(&gl->gl_lockref.lock);
2210 gfs2_dump_glock(seq, gl, fsid);
2211 spin_unlock(&gl->gl_lockref.lock);
2212}
2213
2214static void dump_glock_func(struct gfs2_glock *gl)
2215{
2216 dump_glock(NULL, gl, true);
2217}
2218
2219
2220
2221
2222
2223
2224
2225
2226void gfs2_gl_hash_clear(struct gfs2_sbd *sdp)
2227{
2228 set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags);
2229 flush_workqueue(glock_workqueue);
2230 glock_hash_walk(clear_glock, sdp);
2231 flush_workqueue(glock_workqueue);
2232 wait_event_timeout(sdp->sd_glock_wait,
2233 atomic_read(&sdp->sd_glock_disposal) == 0,
2234 HZ * 600);
2235 glock_hash_walk(dump_glock_func, sdp);
2236}
2237
2238void gfs2_glock_finish_truncate(struct gfs2_inode *ip)
2239{
2240 struct gfs2_glock *gl = ip->i_gl;
2241 int ret;
2242
2243 ret = gfs2_truncatei_resume(ip);
2244 gfs2_glock_assert_withdraw(gl, ret == 0);
2245
2246 spin_lock(&gl->gl_lockref.lock);
2247 clear_bit(GLF_LOCK, &gl->gl_flags);
2248 run_queue(gl, 1);
2249 spin_unlock(&gl->gl_lockref.lock);
2250}
2251
2252static const char *state2str(unsigned state)
2253{
2254 switch(state) {
2255 case LM_ST_UNLOCKED:
2256 return "UN";
2257 case LM_ST_SHARED:
2258 return "SH";
2259 case LM_ST_DEFERRED:
2260 return "DF";
2261 case LM_ST_EXCLUSIVE:
2262 return "EX";
2263 }
2264 return "??";
2265}
2266
2267static const char *hflags2str(char *buf, u16 flags, unsigned long iflags)
2268{
2269 char *p = buf;
2270 if (flags & LM_FLAG_TRY)
2271 *p++ = 't';
2272 if (flags & LM_FLAG_TRY_1CB)
2273 *p++ = 'T';
2274 if (flags & LM_FLAG_NOEXP)
2275 *p++ = 'e';
2276 if (flags & LM_FLAG_ANY)
2277 *p++ = 'A';
2278 if (flags & LM_FLAG_PRIORITY)
2279 *p++ = 'p';
2280 if (flags & LM_FLAG_NODE_SCOPE)
2281 *p++ = 'n';
2282 if (flags & GL_ASYNC)
2283 *p++ = 'a';
2284 if (flags & GL_EXACT)
2285 *p++ = 'E';
2286 if (flags & GL_NOCACHE)
2287 *p++ = 'c';
2288 if (test_bit(HIF_HOLDER, &iflags))
2289 *p++ = 'H';
2290 if (test_bit(HIF_WAIT, &iflags))
2291 *p++ = 'W';
2292 if (test_bit(HIF_MAY_DEMOTE, &iflags))
2293 *p++ = 'D';
2294 if (flags & GL_SKIP)
2295 *p++ = 's';
2296 *p = 0;
2297 return buf;
2298}
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh,
2309 const char *fs_id_buf)
2310{
2311 struct task_struct *gh_owner = NULL;
2312 char flags_buf[32];
2313
2314 rcu_read_lock();
2315 if (gh->gh_owner_pid)
2316 gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID);
2317 gfs2_print_dbg(seq, "%s H: s:%s f:%s e:%d p:%ld [%s] %pS\n",
2318 fs_id_buf, state2str(gh->gh_state),
2319 hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags),
2320 gh->gh_error,
2321 gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1,
2322 gh_owner ? gh_owner->comm : "(ended)",
2323 (void *)gh->gh_ip);
2324 rcu_read_unlock();
2325}
2326
2327static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
2328{
2329 const unsigned long *gflags = &gl->gl_flags;
2330 char *p = buf;
2331
2332 if (test_bit(GLF_LOCK, gflags))
2333 *p++ = 'l';
2334 if (test_bit(GLF_DEMOTE, gflags))
2335 *p++ = 'D';
2336 if (test_bit(GLF_PENDING_DEMOTE, gflags))
2337 *p++ = 'd';
2338 if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags))
2339 *p++ = 'p';
2340 if (test_bit(GLF_DIRTY, gflags))
2341 *p++ = 'y';
2342 if (test_bit(GLF_LFLUSH, gflags))
2343 *p++ = 'f';
2344 if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags))
2345 *p++ = 'i';
2346 if (test_bit(GLF_REPLY_PENDING, gflags))
2347 *p++ = 'r';
2348 if (test_bit(GLF_INITIAL, gflags))
2349 *p++ = 'I';
2350 if (test_bit(GLF_FROZEN, gflags))
2351 *p++ = 'F';
2352 if (!list_empty(&gl->gl_holders))
2353 *p++ = 'q';
2354 if (test_bit(GLF_LRU, gflags))
2355 *p++ = 'L';
2356 if (gl->gl_object)
2357 *p++ = 'o';
2358 if (test_bit(GLF_BLOCKING, gflags))
2359 *p++ = 'b';
2360 if (test_bit(GLF_PENDING_DELETE, gflags))
2361 *p++ = 'P';
2362 if (test_bit(GLF_FREEING, gflags))
2363 *p++ = 'x';
2364 if (test_bit(GLF_INSTANTIATE_NEEDED, gflags))
2365 *p++ = 'n';
2366 if (test_bit(GLF_INSTANTIATE_IN_PROG, gflags))
2367 *p++ = 'N';
2368 *p = 0;
2369 return buf;
2370}
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl, bool fsid)
2391{
2392 const struct gfs2_glock_operations *glops = gl->gl_ops;
2393 unsigned long long dtime;
2394 const struct gfs2_holder *gh;
2395 char gflags_buf[32];
2396 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
2397 char fs_id_buf[sizeof(sdp->sd_fsname) + 7];
2398 unsigned long nrpages = 0;
2399
2400 if (gl->gl_ops->go_flags & GLOF_ASPACE) {
2401 struct address_space *mapping = gfs2_glock2aspace(gl);
2402
2403 nrpages = mapping->nrpages;
2404 }
2405 memset(fs_id_buf, 0, sizeof(fs_id_buf));
2406 if (fsid && sdp)
2407 sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
2408 dtime = jiffies - gl->gl_demote_time;
2409 dtime *= 1000000/HZ;
2410 if (!test_bit(GLF_DEMOTE, &gl->gl_flags))
2411 dtime = 0;
2412 gfs2_print_dbg(seq, "%sG: s:%s n:%u/%llx f:%s t:%s d:%s/%llu a:%d "
2413 "v:%d r:%d m:%ld p:%lu\n",
2414 fs_id_buf, state2str(gl->gl_state),
2415 gl->gl_name.ln_type,
2416 (unsigned long long)gl->gl_name.ln_number,
2417 gflags2str(gflags_buf, gl),
2418 state2str(gl->gl_target),
2419 state2str(gl->gl_demote_state), dtime,
2420 atomic_read(&gl->gl_ail_count),
2421 atomic_read(&gl->gl_revokes),
2422 (int)gl->gl_lockref.count, gl->gl_hold_time, nrpages);
2423
2424 list_for_each_entry(gh, &gl->gl_holders, gh_list)
2425 dump_holder(seq, gh, fs_id_buf);
2426
2427 if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump)
2428 glops->go_dump(seq, gl, fs_id_buf);
2429}
2430
2431static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr)
2432{
2433 struct gfs2_glock *gl = iter_ptr;
2434
2435 seq_printf(seq, "G: n:%u/%llx rtt:%llu/%llu rttb:%llu/%llu irt:%llu/%llu dcnt: %llu qcnt: %llu\n",
2436 gl->gl_name.ln_type,
2437 (unsigned long long)gl->gl_name.ln_number,
2438 (unsigned long long)gl->gl_stats.stats[GFS2_LKS_SRTT],
2439 (unsigned long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR],
2440 (unsigned long long)gl->gl_stats.stats[GFS2_LKS_SRTTB],
2441 (unsigned long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB],
2442 (unsigned long long)gl->gl_stats.stats[GFS2_LKS_SIRT],
2443 (unsigned long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR],
2444 (unsigned long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT],
2445 (unsigned long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]);
2446 return 0;
2447}
2448
2449static const char *gfs2_gltype[] = {
2450 "type",
2451 "reserved",
2452 "nondisk",
2453 "inode",
2454 "rgrp",
2455 "meta",
2456 "iopen",
2457 "flock",
2458 "plock",
2459 "quota",
2460 "journal",
2461};
2462
2463static const char *gfs2_stype[] = {
2464 [GFS2_LKS_SRTT] = "srtt",
2465 [GFS2_LKS_SRTTVAR] = "srttvar",
2466 [GFS2_LKS_SRTTB] = "srttb",
2467 [GFS2_LKS_SRTTVARB] = "srttvarb",
2468 [GFS2_LKS_SIRT] = "sirt",
2469 [GFS2_LKS_SIRTVAR] = "sirtvar",
2470 [GFS2_LKS_DCOUNT] = "dlm",
2471 [GFS2_LKS_QCOUNT] = "queue",
2472};
2473
2474#define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype))
2475
2476static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr)
2477{
2478 struct gfs2_sbd *sdp = seq->private;
2479 loff_t pos = *(loff_t *)iter_ptr;
2480 unsigned index = pos >> 3;
2481 unsigned subindex = pos & 0x07;
2482 int i;
2483
2484 if (index == 0 && subindex != 0)
2485 return 0;
2486
2487 seq_printf(seq, "%-10s %8s:", gfs2_gltype[index],
2488 (index == 0) ? "cpu": gfs2_stype[subindex]);
2489
2490 for_each_possible_cpu(i) {
2491 const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i);
2492
2493 if (index == 0)
2494 seq_printf(seq, " %15u", i);
2495 else
2496 seq_printf(seq, " %15llu", (unsigned long long)lkstats->
2497 lkstats[index - 1].stats[subindex]);
2498 }
2499 seq_putc(seq, '\n');
2500 return 0;
2501}
2502
2503int __init gfs2_glock_init(void)
2504{
2505 int i, ret;
2506
2507 ret = rhashtable_init(&gl_hash_table, &ht_parms);
2508 if (ret < 0)
2509 return ret;
2510
2511 glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM |
2512 WQ_HIGHPRI | WQ_FREEZABLE, 0);
2513 if (!glock_workqueue) {
2514 rhashtable_destroy(&gl_hash_table);
2515 return -ENOMEM;
2516 }
2517 gfs2_delete_workqueue = alloc_workqueue("delete_workqueue",
2518 WQ_MEM_RECLAIM | WQ_FREEZABLE,
2519 0);
2520 if (!gfs2_delete_workqueue) {
2521 destroy_workqueue(glock_workqueue);
2522 rhashtable_destroy(&gl_hash_table);
2523 return -ENOMEM;
2524 }
2525
2526 ret = register_shrinker(&glock_shrinker);
2527 if (ret) {
2528 destroy_workqueue(gfs2_delete_workqueue);
2529 destroy_workqueue(glock_workqueue);
2530 rhashtable_destroy(&gl_hash_table);
2531 return ret;
2532 }
2533
2534 for (i = 0; i < GLOCK_WAIT_TABLE_SIZE; i++)
2535 init_waitqueue_head(glock_wait_table + i);
2536
2537 return 0;
2538}
2539
2540void gfs2_glock_exit(void)
2541{
2542 unregister_shrinker(&glock_shrinker);
2543 rhashtable_destroy(&gl_hash_table);
2544 destroy_workqueue(glock_workqueue);
2545 destroy_workqueue(gfs2_delete_workqueue);
2546}
2547
2548static void gfs2_glock_iter_next(struct gfs2_glock_iter *gi, loff_t n)
2549{
2550 struct gfs2_glock *gl = gi->gl;
2551
2552 if (gl) {
2553 if (n == 0)
2554 return;
2555 if (!lockref_put_not_zero(&gl->gl_lockref))
2556 gfs2_glock_queue_put(gl);
2557 }
2558 for (;;) {
2559 gl = rhashtable_walk_next(&gi->hti);
2560 if (IS_ERR_OR_NULL(gl)) {
2561 if (gl == ERR_PTR(-EAGAIN)) {
2562 n = 1;
2563 continue;
2564 }
2565 gl = NULL;
2566 break;
2567 }
2568 if (gl->gl_name.ln_sbd != gi->sdp)
2569 continue;
2570 if (n <= 1) {
2571 if (!lockref_get_not_dead(&gl->gl_lockref))
2572 continue;
2573 break;
2574 } else {
2575 if (__lockref_is_dead(&gl->gl_lockref))
2576 continue;
2577 n--;
2578 }
2579 }
2580 gi->gl = gl;
2581}
2582
2583static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
2584 __acquires(RCU)
2585{
2586 struct gfs2_glock_iter *gi = seq->private;
2587 loff_t n;
2588
2589
2590
2591
2592
2593 if (*pos < gi->last_pos) {
2594 rhashtable_walk_exit(&gi->hti);
2595 rhashtable_walk_enter(&gl_hash_table, &gi->hti);
2596 n = *pos + 1;
2597 } else {
2598 n = *pos - gi->last_pos;
2599 }
2600
2601 rhashtable_walk_start(&gi->hti);
2602
2603 gfs2_glock_iter_next(gi, n);
2604 gi->last_pos = *pos;
2605 return gi->gl;
2606}
2607
2608static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr,
2609 loff_t *pos)
2610{
2611 struct gfs2_glock_iter *gi = seq->private;
2612
2613 (*pos)++;
2614 gi->last_pos = *pos;
2615 gfs2_glock_iter_next(gi, 1);
2616 return gi->gl;
2617}
2618
2619static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
2620 __releases(RCU)
2621{
2622 struct gfs2_glock_iter *gi = seq->private;
2623
2624 rhashtable_walk_stop(&gi->hti);
2625}
2626
2627static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
2628{
2629 dump_glock(seq, iter_ptr, false);
2630 return 0;
2631}
2632
2633static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos)
2634{
2635 preempt_disable();
2636 if (*pos >= GFS2_NR_SBSTATS)
2637 return NULL;
2638 return pos;
2639}
2640
2641static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr,
2642 loff_t *pos)
2643{
2644 (*pos)++;
2645 if (*pos >= GFS2_NR_SBSTATS)
2646 return NULL;
2647 return pos;
2648}
2649
2650static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr)
2651{
2652 preempt_enable();
2653}
2654
2655static const struct seq_operations gfs2_glock_seq_ops = {
2656 .start = gfs2_glock_seq_start,
2657 .next = gfs2_glock_seq_next,
2658 .stop = gfs2_glock_seq_stop,
2659 .show = gfs2_glock_seq_show,
2660};
2661
2662static const struct seq_operations gfs2_glstats_seq_ops = {
2663 .start = gfs2_glock_seq_start,
2664 .next = gfs2_glock_seq_next,
2665 .stop = gfs2_glock_seq_stop,
2666 .show = gfs2_glstats_seq_show,
2667};
2668
2669static const struct seq_operations gfs2_sbstats_sops = {
2670 .start = gfs2_sbstats_seq_start,
2671 .next = gfs2_sbstats_seq_next,
2672 .stop = gfs2_sbstats_seq_stop,
2673 .show = gfs2_sbstats_seq_show,
2674};
2675
2676#define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL)
2677
2678static int __gfs2_glocks_open(struct inode *inode, struct file *file,
2679 const struct seq_operations *ops)
2680{
2681 int ret = seq_open_private(file, ops, sizeof(struct gfs2_glock_iter));
2682 if (ret == 0) {
2683 struct seq_file *seq = file->private_data;
2684 struct gfs2_glock_iter *gi = seq->private;
2685
2686 gi->sdp = inode->i_private;
2687 seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
2688 if (seq->buf)
2689 seq->size = GFS2_SEQ_GOODSIZE;
2690
2691
2692
2693
2694 gi->last_pos = -1;
2695 gi->gl = NULL;
2696 rhashtable_walk_enter(&gl_hash_table, &gi->hti);
2697 }
2698 return ret;
2699}
2700
2701static int gfs2_glocks_open(struct inode *inode, struct file *file)
2702{
2703 return __gfs2_glocks_open(inode, file, &gfs2_glock_seq_ops);
2704}
2705
2706static int gfs2_glocks_release(struct inode *inode, struct file *file)
2707{
2708 struct seq_file *seq = file->private_data;
2709 struct gfs2_glock_iter *gi = seq->private;
2710
2711 if (gi->gl)
2712 gfs2_glock_put(gi->gl);
2713 rhashtable_walk_exit(&gi->hti);
2714 return seq_release_private(inode, file);
2715}
2716
2717static int gfs2_glstats_open(struct inode *inode, struct file *file)
2718{
2719 return __gfs2_glocks_open(inode, file, &gfs2_glstats_seq_ops);
2720}
2721
2722static const struct file_operations gfs2_glocks_fops = {
2723 .owner = THIS_MODULE,
2724 .open = gfs2_glocks_open,
2725 .read = seq_read,
2726 .llseek = seq_lseek,
2727 .release = gfs2_glocks_release,
2728};
2729
2730static const struct file_operations gfs2_glstats_fops = {
2731 .owner = THIS_MODULE,
2732 .open = gfs2_glstats_open,
2733 .read = seq_read,
2734 .llseek = seq_lseek,
2735 .release = gfs2_glocks_release,
2736};
2737
2738DEFINE_SEQ_ATTRIBUTE(gfs2_sbstats);
2739
2740void gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
2741{
2742 sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root);
2743
2744 debugfs_create_file("glocks", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp,
2745 &gfs2_glocks_fops);
2746
2747 debugfs_create_file("glstats", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp,
2748 &gfs2_glstats_fops);
2749
2750 debugfs_create_file("sbstats", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp,
2751 &gfs2_sbstats_fops);
2752}
2753
2754void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp)
2755{
2756 debugfs_remove_recursive(sdp->debugfs_dir);
2757 sdp->debugfs_dir = NULL;
2758}
2759
2760void gfs2_register_debugfs(void)
2761{
2762 gfs2_root = debugfs_create_dir("gfs2", NULL);
2763}
2764
2765void gfs2_unregister_debugfs(void)
2766{
2767 debugfs_remove(gfs2_root);
2768 gfs2_root = NULL;
2769}
2770