forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathgc.c
1115 lines (936 loc) · 27.3 KB
/
gc.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* fs/f2fs/gc.c
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/backing-dev.h>
#include <linux/init.h>
#include <linux/f2fs_fs.h>
#include <linux/kthread.h>
#include <linux/delay.h>
#include <linux/freezer.h>
#include "f2fs.h"
#include "node.h"
#include "segment.h"
#include "gc.h"
#include <trace/events/f2fs.h>
static int gc_thread_func(void *data)
{
struct f2fs_sb_info *sbi = data;
struct f2fs_gc_kthread *gc_th = sbi->gc_thread;
wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head;
unsigned int wait_ms;
wait_ms = gc_th->min_sleep_time;
set_freezable();
do {
wait_event_interruptible_timeout(*wq,
kthread_should_stop() || freezing(current) ||
gc_th->gc_wake,
msecs_to_jiffies(wait_ms));
/* give it a try one time */
if (gc_th->gc_wake)
gc_th->gc_wake = 0;
if (try_to_freeze())
continue;
if (kthread_should_stop())
break;
if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) {
increase_sleep_time(gc_th, &wait_ms);
continue;
}
#ifdef CONFIG_F2FS_FAULT_INJECTION
if (time_to_inject(sbi, FAULT_CHECKPOINT)) {
f2fs_show_injection_info(FAULT_CHECKPOINT);
f2fs_stop_checkpoint(sbi, false);
}
#endif
if (!sb_start_write_trylock(sbi->sb))
continue;
/*
* [GC triggering condition]
* 0. GC is not conducted currently.
* 1. There are enough dirty segments.
* 2. IO subsystem is idle by checking the # of writeback pages.
* 3. IO subsystem is idle by checking the # of requests in
* bdev's request list.
*
* Note) We have to avoid triggering GCs frequently.
* Because it is possible that some segments can be
* invalidated soon after by user update or deletion.
* So, I'd like to wait some time to collect dirty segments.
*/
if (!mutex_trylock(&sbi->gc_mutex))
goto next;
if (gc_th->gc_urgent) {
wait_ms = gc_th->urgent_sleep_time;
goto do_gc;
}
if (!is_idle(sbi)) {
increase_sleep_time(gc_th, &wait_ms);
mutex_unlock(&sbi->gc_mutex);
goto next;
}
if (has_enough_invalid_blocks(sbi))
decrease_sleep_time(gc_th, &wait_ms);
else
increase_sleep_time(gc_th, &wait_ms);
do_gc:
stat_inc_bggc_count(sbi);
/* if return value is not zero, no victim was selected */
if (f2fs_gc(sbi, test_opt(sbi, FORCE_FG_GC), true, NULL_SEGNO))
wait_ms = gc_th->no_gc_sleep_time;
trace_f2fs_background_gc(sbi->sb, wait_ms,
prefree_segments(sbi), free_segments(sbi));
/* balancing f2fs's metadata periodically */
f2fs_balance_fs_bg(sbi);
next:
sb_end_write(sbi->sb);
} while (!kthread_should_stop());
return 0;
}
int start_gc_thread(struct f2fs_sb_info *sbi)
{
struct f2fs_gc_kthread *gc_th;
dev_t dev = sbi->sb->s_bdev->bd_dev;
int err = 0;
gc_th = f2fs_kmalloc(sbi, sizeof(struct f2fs_gc_kthread), GFP_KERNEL);
if (!gc_th) {
err = -ENOMEM;
goto out;
}
gc_th->urgent_sleep_time = DEF_GC_THREAD_URGENT_SLEEP_TIME;
gc_th->min_sleep_time = DEF_GC_THREAD_MIN_SLEEP_TIME;
gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME;
gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME;
gc_th->gc_idle = 0;
gc_th->gc_urgent = 0;
gc_th->gc_wake= 0;
sbi->gc_thread = gc_th;
init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head);
sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi,
"f2fs_gc-%u:%u", MAJOR(dev), MINOR(dev));
if (IS_ERR(gc_th->f2fs_gc_task)) {
err = PTR_ERR(gc_th->f2fs_gc_task);
kfree(gc_th);
sbi->gc_thread = NULL;
}
out:
return err;
}
void stop_gc_thread(struct f2fs_sb_info *sbi)
{
struct f2fs_gc_kthread *gc_th = sbi->gc_thread;
if (!gc_th)
return;
kthread_stop(gc_th->f2fs_gc_task);
kfree(gc_th);
sbi->gc_thread = NULL;
}
static int select_gc_type(struct f2fs_gc_kthread *gc_th, int gc_type)
{
int gc_mode = (gc_type == BG_GC) ? GC_CB : GC_GREEDY;
if (gc_th && gc_th->gc_idle) {
if (gc_th->gc_idle == 1)
gc_mode = GC_CB;
else if (gc_th->gc_idle == 2)
gc_mode = GC_GREEDY;
}
return gc_mode;
}
static void select_policy(struct f2fs_sb_info *sbi, int gc_type,
int type, struct victim_sel_policy *p)
{
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
if (p->alloc_mode == SSR) {
p->gc_mode = GC_GREEDY;
p->dirty_segmap = dirty_i->dirty_segmap[type];
p->max_search = dirty_i->nr_dirty[type];
p->ofs_unit = 1;
} else {
p->gc_mode = select_gc_type(sbi->gc_thread, gc_type);
p->dirty_segmap = dirty_i->dirty_segmap[DIRTY];
p->max_search = dirty_i->nr_dirty[DIRTY];
p->ofs_unit = sbi->segs_per_sec;
}
/* we need to check every dirty segments in the FG_GC case */
if (gc_type != FG_GC && p->max_search > sbi->max_victim_search)
p->max_search = sbi->max_victim_search;
/* let's select beginning hot/small space first */
if (type == CURSEG_HOT_DATA || IS_NODESEG(type))
p->offset = 0;
else
p->offset = SIT_I(sbi)->last_victim[p->gc_mode];
}
static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
struct victim_sel_policy *p)
{
/* SSR allocates in a segment unit */
if (p->alloc_mode == SSR)
return sbi->blocks_per_seg;
if (p->gc_mode == GC_GREEDY)
return 2 * sbi->blocks_per_seg * p->ofs_unit;
else if (p->gc_mode == GC_CB)
return UINT_MAX;
else /* No other gc_mode */
return 0;
}
static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
{
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
unsigned int secno;
/*
* If the gc_type is FG_GC, we can select victim segments
* selected by background GC before.
* Those segments guarantee they have small valid blocks.
*/
for_each_set_bit(secno, dirty_i->victim_secmap, MAIN_SECS(sbi)) {
if (sec_usage_check(sbi, secno))
continue;
if (no_fggc_candidate(sbi, secno))
continue;
clear_bit(secno, dirty_i->victim_secmap);
return GET_SEG_FROM_SEC(sbi, secno);
}
return NULL_SEGNO;
}
static unsigned int get_cb_cost(struct f2fs_sb_info *sbi, unsigned int segno)
{
struct sit_info *sit_i = SIT_I(sbi);
unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
unsigned int start = GET_SEG_FROM_SEC(sbi, secno);
unsigned long long mtime = 0;
unsigned int vblocks;
unsigned char age = 0;
unsigned char u;
unsigned int i;
for (i = 0; i < sbi->segs_per_sec; i++)
mtime += get_seg_entry(sbi, start + i)->mtime;
vblocks = get_valid_blocks(sbi, segno, true);
mtime = div_u64(mtime, sbi->segs_per_sec);
vblocks = div_u64(vblocks, sbi->segs_per_sec);
u = (vblocks * 100) >> sbi->log_blocks_per_seg;
/* Handle if the system time has changed by the user */
if (mtime < sit_i->min_mtime)
sit_i->min_mtime = mtime;
if (mtime > sit_i->max_mtime)
sit_i->max_mtime = mtime;
if (sit_i->max_mtime != sit_i->min_mtime)
age = 100 - div64_u64(100 * (mtime - sit_i->min_mtime),
sit_i->max_mtime - sit_i->min_mtime);
return UINT_MAX - ((100 * (100 - u) * age) / (100 + u));
}
static inline unsigned int get_gc_cost(struct f2fs_sb_info *sbi,
unsigned int segno, struct victim_sel_policy *p)
{
if (p->alloc_mode == SSR)
return get_seg_entry(sbi, segno)->ckpt_valid_blocks;
/* alloc_mode == LFS */
if (p->gc_mode == GC_GREEDY)
return get_valid_blocks(sbi, segno, true);
else
return get_cb_cost(sbi, segno);
}
static unsigned int count_bits(const unsigned long *addr,
unsigned int offset, unsigned int len)
{
unsigned int end = offset + len, sum = 0;
while (offset < end) {
if (test_bit(offset++, addr))
++sum;
}
return sum;
}
/*
* This function is called from two paths.
* One is garbage collection and the other is SSR segment selection.
* When it is called during GC, it just gets a victim segment
* and it does not remove it from dirty seglist.
* When it is called from SSR segment selection, it finds a segment
* which has minimum valid blocks and removes it from dirty seglist.
*/
static int get_victim_by_default(struct f2fs_sb_info *sbi,
unsigned int *result, int gc_type, int type, char alloc_mode)
{
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
struct sit_info *sm = SIT_I(sbi);
struct victim_sel_policy p;
unsigned int secno, last_victim;
unsigned int last_segment = MAIN_SEGS(sbi);
unsigned int nsearched = 0;
mutex_lock(&dirty_i->seglist_lock);
p.alloc_mode = alloc_mode;
select_policy(sbi, gc_type, type, &p);
p.min_segno = NULL_SEGNO;
p.min_cost = get_max_cost(sbi, &p);
if (*result != NULL_SEGNO) {
if (IS_DATASEG(get_seg_entry(sbi, *result)->type) &&
get_valid_blocks(sbi, *result, false) &&
!sec_usage_check(sbi, GET_SEC_FROM_SEG(sbi, *result)))
p.min_segno = *result;
goto out;
}
if (p.max_search == 0)
goto out;
last_victim = sm->last_victim[p.gc_mode];
if (p.alloc_mode == LFS && gc_type == FG_GC) {
p.min_segno = check_bg_victims(sbi);
if (p.min_segno != NULL_SEGNO)
goto got_it;
}
while (1) {
unsigned long cost;
unsigned int segno;
segno = find_next_bit(p.dirty_segmap, last_segment, p.offset);
if (segno >= last_segment) {
if (sm->last_victim[p.gc_mode]) {
last_segment =
sm->last_victim[p.gc_mode];
sm->last_victim[p.gc_mode] = 0;
p.offset = 0;
continue;
}
break;
}
p.offset = segno + p.ofs_unit;
if (p.ofs_unit > 1) {
p.offset -= segno % p.ofs_unit;
nsearched += count_bits(p.dirty_segmap,
p.offset - p.ofs_unit,
p.ofs_unit);
} else {
nsearched++;
}
secno = GET_SEC_FROM_SEG(sbi, segno);
if (sec_usage_check(sbi, secno))
goto next;
if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap))
goto next;
if (gc_type == FG_GC && p.alloc_mode == LFS &&
no_fggc_candidate(sbi, secno))
goto next;
cost = get_gc_cost(sbi, segno, &p);
if (p.min_cost > cost) {
p.min_segno = segno;
p.min_cost = cost;
}
next:
if (nsearched >= p.max_search) {
if (!sm->last_victim[p.gc_mode] && segno <= last_victim)
sm->last_victim[p.gc_mode] = last_victim + 1;
else
sm->last_victim[p.gc_mode] = segno + 1;
sm->last_victim[p.gc_mode] %= MAIN_SEGS(sbi);
break;
}
}
if (p.min_segno != NULL_SEGNO) {
got_it:
if (p.alloc_mode == LFS) {
secno = GET_SEC_FROM_SEG(sbi, p.min_segno);
if (gc_type == FG_GC)
sbi->cur_victim_sec = secno;
else
set_bit(secno, dirty_i->victim_secmap);
}
*result = (p.min_segno / p.ofs_unit) * p.ofs_unit;
trace_f2fs_get_victim(sbi->sb, type, gc_type, &p,
sbi->cur_victim_sec,
prefree_segments(sbi), free_segments(sbi));
}
out:
mutex_unlock(&dirty_i->seglist_lock);
return (p.min_segno == NULL_SEGNO) ? 0 : 1;
}
static const struct victim_selection default_v_ops = {
.get_victim = get_victim_by_default,
};
static struct inode *find_gc_inode(struct gc_inode_list *gc_list, nid_t ino)
{
struct inode_entry *ie;
ie = radix_tree_lookup(&gc_list->iroot, ino);
if (ie)
return ie->inode;
return NULL;
}
static void add_gc_inode(struct gc_inode_list *gc_list, struct inode *inode)
{
struct inode_entry *new_ie;
if (inode == find_gc_inode(gc_list, inode->i_ino)) {
iput(inode);
return;
}
new_ie = f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS);
new_ie->inode = inode;
f2fs_radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie);
list_add_tail(&new_ie->list, &gc_list->ilist);
}
static void put_gc_inode(struct gc_inode_list *gc_list)
{
struct inode_entry *ie, *next_ie;
list_for_each_entry_safe(ie, next_ie, &gc_list->ilist, list) {
radix_tree_delete(&gc_list->iroot, ie->inode->i_ino);
iput(ie->inode);
list_del(&ie->list);
kmem_cache_free(inode_entry_slab, ie);
}
}
static int check_valid_map(struct f2fs_sb_info *sbi,
unsigned int segno, int offset)
{
struct sit_info *sit_i = SIT_I(sbi);
struct seg_entry *sentry;
int ret;
down_read(&sit_i->sentry_lock);
sentry = get_seg_entry(sbi, segno);
ret = f2fs_test_bit(offset, sentry->cur_valid_map);
up_read(&sit_i->sentry_lock);
return ret;
}
/*
* This function compares node address got in summary with that in NAT.
* On validity, copy that node with cold status, otherwise (invalid node)
* ignore that.
*/
static void gc_node_segment(struct f2fs_sb_info *sbi,
struct f2fs_summary *sum, unsigned int segno, int gc_type)
{
struct f2fs_summary *entry;
block_t start_addr;
int off;
int phase = 0;
start_addr = START_BLOCK(sbi, segno);
next_step:
entry = sum;
for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
nid_t nid = le32_to_cpu(entry->nid);
struct page *node_page;
struct node_info ni;
/* stop BG_GC if there is not enough free sections. */
if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0))
return;
if (check_valid_map(sbi, segno, off) == 0)
continue;
if (phase == 0) {
ra_meta_pages(sbi, NAT_BLOCK_OFFSET(nid), 1,
META_NAT, true);
continue;
}
if (phase == 1) {
ra_node_page(sbi, nid);
continue;
}
/* phase == 2 */
node_page = get_node_page(sbi, nid);
if (IS_ERR(node_page))
continue;
/* block may become invalid during get_node_page */
if (check_valid_map(sbi, segno, off) == 0) {
f2fs_put_page(node_page, 1);
continue;
}
get_node_info(sbi, nid, &ni);
if (ni.blk_addr != start_addr + off) {
f2fs_put_page(node_page, 1);
continue;
}
move_node_page(node_page, gc_type);
stat_inc_node_blk_count(sbi, 1, gc_type);
}
if (++phase < 3)
goto next_step;
}
/*
* Calculate start block index indicating the given node offset.
* Be careful, caller should give this node offset only indicating direct node
* blocks. If any node offsets, which point the other types of node blocks such
* as indirect or double indirect node blocks, are given, it must be a caller's
* bug.
*/
block_t start_bidx_of_node(unsigned int node_ofs, struct inode *inode)
{
unsigned int indirect_blks = 2 * NIDS_PER_BLOCK + 4;
unsigned int bidx;
if (node_ofs == 0)
return 0;
if (node_ofs <= 2) {
bidx = node_ofs - 1;
} else if (node_ofs <= indirect_blks) {
int dec = (node_ofs - 4) / (NIDS_PER_BLOCK + 1);
bidx = node_ofs - 2 - dec;
} else {
int dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1);
bidx = node_ofs - 5 - dec;
}
return bidx * ADDRS_PER_BLOCK + ADDRS_PER_INODE(inode);
}
static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
struct node_info *dni, block_t blkaddr, unsigned int *nofs)
{
struct page *node_page;
nid_t nid;
unsigned int ofs_in_node;
block_t source_blkaddr;
nid = le32_to_cpu(sum->nid);
ofs_in_node = le16_to_cpu(sum->ofs_in_node);
node_page = get_node_page(sbi, nid);
if (IS_ERR(node_page))
return false;
get_node_info(sbi, nid, dni);
if (sum->version != dni->version) {
f2fs_msg(sbi->sb, KERN_WARNING,
"%s: valid data with mismatched node version.",
__func__);
set_sbi_flag(sbi, SBI_NEED_FSCK);
}
*nofs = ofs_of_node(node_page);
source_blkaddr = datablock_addr(NULL, node_page, ofs_in_node);
f2fs_put_page(node_page, 1);
if (source_blkaddr != blkaddr)
return false;
return true;
}
/*
* Move data block via META_MAPPING while keeping locked data page.
* This can be used to move blocks, aka LBAs, directly on disk.
*/
static void move_data_block(struct inode *inode, block_t bidx,
unsigned int segno, int off)
{
struct f2fs_io_info fio = {
.sbi = F2FS_I_SB(inode),
.ino = inode->i_ino,
.type = DATA,
.temp = COLD,
.op = REQ_OP_READ,
.op_flags = 0,
.encrypted_page = NULL,
.in_list = false,
};
struct dnode_of_data dn;
struct f2fs_summary sum;
struct node_info ni;
struct page *page;
block_t newaddr;
int err;
/* do not read out */
page = f2fs_grab_cache_page(inode->i_mapping, bidx, false);
if (!page)
return;
if (!check_valid_map(F2FS_I_SB(inode), segno, off))
goto out;
if (f2fs_is_atomic_file(inode))
goto out;
if (f2fs_is_pinned_file(inode)) {
f2fs_pin_file_control(inode, true);
goto out;
}
set_new_dnode(&dn, inode, NULL, NULL, 0);
err = get_dnode_of_data(&dn, bidx, LOOKUP_NODE);
if (err)
goto out;
if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
ClearPageUptodate(page);
goto put_out;
}
/*
* don't cache encrypted data into meta inode until previous dirty
* data were writebacked to avoid racing between GC and flush.
*/
f2fs_wait_on_page_writeback(page, DATA, true);
get_node_info(fio.sbi, dn.nid, &ni);
set_summary(&sum, dn.nid, dn.ofs_in_node, ni.version);
/* read page */
fio.page = page;
fio.new_blkaddr = fio.old_blkaddr = dn.data_blkaddr;
allocate_data_block(fio.sbi, NULL, fio.old_blkaddr, &newaddr,
&sum, CURSEG_COLD_DATA, NULL, false);
fio.encrypted_page = f2fs_pagecache_get_page(META_MAPPING(fio.sbi),
newaddr, FGP_LOCK | FGP_CREAT, GFP_NOFS);
if (!fio.encrypted_page) {
err = -ENOMEM;
goto recover_block;
}
err = f2fs_submit_page_bio(&fio);
if (err)
goto put_page_out;
/* write page */
lock_page(fio.encrypted_page);
if (unlikely(fio.encrypted_page->mapping != META_MAPPING(fio.sbi))) {
err = -EIO;
goto put_page_out;
}
if (unlikely(!PageUptodate(fio.encrypted_page))) {
err = -EIO;
goto put_page_out;
}
set_page_dirty(fio.encrypted_page);
f2fs_wait_on_page_writeback(fio.encrypted_page, DATA, true);
if (clear_page_dirty_for_io(fio.encrypted_page))
dec_page_count(fio.sbi, F2FS_DIRTY_META);
set_page_writeback(fio.encrypted_page);
/* allocate block address */
f2fs_wait_on_page_writeback(dn.node_page, NODE, true);
fio.op = REQ_OP_WRITE;
fio.op_flags = REQ_SYNC;
fio.new_blkaddr = newaddr;
err = f2fs_submit_page_write(&fio);
if (err) {
if (PageWriteback(fio.encrypted_page))
end_page_writeback(fio.encrypted_page);
goto put_page_out;
}
f2fs_update_iostat(fio.sbi, FS_GC_DATA_IO, F2FS_BLKSIZE);
f2fs_update_data_blkaddr(&dn, newaddr);
set_inode_flag(inode, FI_APPEND_WRITE);
if (page->index == 0)
set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
put_page_out:
f2fs_put_page(fio.encrypted_page, 1);
recover_block:
if (err)
__f2fs_replace_block(fio.sbi, &sum, newaddr, fio.old_blkaddr,
true, true);
put_out:
f2fs_put_dnode(&dn);
out:
f2fs_put_page(page, 1);
}
static void move_data_page(struct inode *inode, block_t bidx, int gc_type,
unsigned int segno, int off)
{
struct page *page;
page = get_lock_data_page(inode, bidx, true);
if (IS_ERR(page))
return;
if (!check_valid_map(F2FS_I_SB(inode), segno, off))
goto out;
if (f2fs_is_atomic_file(inode))
goto out;
if (f2fs_is_pinned_file(inode)) {
if (gc_type == FG_GC)
f2fs_pin_file_control(inode, true);
goto out;
}
if (gc_type == BG_GC) {
if (PageWriteback(page))
goto out;
set_page_dirty(page);
set_cold_data(page);
} else {
struct f2fs_io_info fio = {
.sbi = F2FS_I_SB(inode),
.ino = inode->i_ino,
.type = DATA,
.temp = COLD,
.op = REQ_OP_WRITE,
.op_flags = REQ_SYNC,
.old_blkaddr = NULL_ADDR,
.page = page,
.encrypted_page = NULL,
.need_lock = LOCK_REQ,
.io_type = FS_GC_DATA_IO,
};
bool is_dirty = PageDirty(page);
int err;
retry:
set_page_dirty(page);
f2fs_wait_on_page_writeback(page, DATA, true);
if (clear_page_dirty_for_io(page)) {
inode_dec_dirty_pages(inode);
remove_dirty_inode(inode);
}
set_cold_data(page);
err = do_write_data_page(&fio);
if (err == -ENOMEM && is_dirty) {
congestion_wait(BLK_RW_ASYNC, HZ/50);
goto retry;
}
}
out:
f2fs_put_page(page, 1);
}
/*
* This function tries to get parent node of victim data block, and identifies
* data block validity. If the block is valid, copy that with cold status and
* modify parent node.
* If the parent node is not valid or the data block address is different,
* the victim data block is ignored.
*/
static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
struct gc_inode_list *gc_list, unsigned int segno, int gc_type)
{
struct super_block *sb = sbi->sb;
struct f2fs_summary *entry;
block_t start_addr;
int off;
int phase = 0;
start_addr = START_BLOCK(sbi, segno);
next_step:
entry = sum;
for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
struct page *data_page;
struct inode *inode;
struct node_info dni; /* dnode info for the data */
unsigned int ofs_in_node, nofs;
block_t start_bidx;
nid_t nid = le32_to_cpu(entry->nid);
/* stop BG_GC if there is not enough free sections. */
if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0))
return;
if (check_valid_map(sbi, segno, off) == 0)
continue;
if (phase == 0) {
ra_meta_pages(sbi, NAT_BLOCK_OFFSET(nid), 1,
META_NAT, true);
continue;
}
if (phase == 1) {
ra_node_page(sbi, nid);
continue;
}
/* Get an inode by ino with checking validity */
if (!is_alive(sbi, entry, &dni, start_addr + off, &nofs))
continue;
if (phase == 2) {
ra_node_page(sbi, dni.ino);
continue;
}
ofs_in_node = le16_to_cpu(entry->ofs_in_node);
if (phase == 3) {
inode = f2fs_iget(sb, dni.ino);
if (IS_ERR(inode) || is_bad_inode(inode))
continue;
/* if encrypted inode, let's go phase 3 */
if (f2fs_encrypted_file(inode)) {
add_gc_inode(gc_list, inode);
continue;
}
if (!down_write_trylock(
&F2FS_I(inode)->dio_rwsem[WRITE])) {
iput(inode);
continue;
}
start_bidx = start_bidx_of_node(nofs, inode);
data_page = get_read_data_page(inode,
start_bidx + ofs_in_node, REQ_RAHEAD,
true);
up_write(&F2FS_I(inode)->dio_rwsem[WRITE]);
if (IS_ERR(data_page)) {
iput(inode);
continue;
}
f2fs_put_page(data_page, 0);
add_gc_inode(gc_list, inode);
continue;
}
/* phase 4 */
inode = find_gc_inode(gc_list, dni.ino);
if (inode) {
struct f2fs_inode_info *fi = F2FS_I(inode);
bool locked = false;
if (S_ISREG(inode->i_mode)) {
if (!down_write_trylock(&fi->dio_rwsem[READ]))
continue;
if (!down_write_trylock(
&fi->dio_rwsem[WRITE])) {
up_write(&fi->dio_rwsem[READ]);
continue;
}
locked = true;
/* wait for all inflight aio data */
inode_dio_wait(inode);
}
start_bidx = start_bidx_of_node(nofs, inode)
+ ofs_in_node;
if (f2fs_encrypted_file(inode))
move_data_block(inode, start_bidx, segno, off);
else
move_data_page(inode, start_bidx, gc_type,
segno, off);
if (locked) {
up_write(&fi->dio_rwsem[WRITE]);
up_write(&fi->dio_rwsem[READ]);
}
stat_inc_data_blk_count(sbi, 1, gc_type);
}
}
if (++phase < 5)
goto next_step;
}
static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim,
int gc_type)
{
struct sit_info *sit_i = SIT_I(sbi);
int ret;
down_write(&sit_i->sentry_lock);
ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type,
NO_CHECK_TYPE, LFS);
up_write(&sit_i->sentry_lock);
return ret;
}
static int do_garbage_collect(struct f2fs_sb_info *sbi,
unsigned int start_segno,
struct gc_inode_list *gc_list, int gc_type)
{
struct page *sum_page;
struct f2fs_summary_block *sum;
struct blk_plug plug;
unsigned int segno = start_segno;
unsigned int end_segno = start_segno + sbi->segs_per_sec;
int seg_freed = 0;
unsigned char type = IS_DATASEG(get_seg_entry(sbi, segno)->type) ?
SUM_TYPE_DATA : SUM_TYPE_NODE;
/* readahead multi ssa blocks those have contiguous address */
if (sbi->segs_per_sec > 1)
ra_meta_pages(sbi, GET_SUM_BLOCK(sbi, segno),
sbi->segs_per_sec, META_SSA, true);
/* reference all summary page */
while (segno < end_segno) {
sum_page = get_sum_page(sbi, segno++);
unlock_page(sum_page);
}
blk_start_plug(&plug);
for (segno = start_segno; segno < end_segno; segno++) {
/* find segment summary of victim */
sum_page = find_get_page(META_MAPPING(sbi),
GET_SUM_BLOCK(sbi, segno));
f2fs_put_page(sum_page, 0);
if (get_valid_blocks(sbi, segno, false) == 0 ||
!PageUptodate(sum_page) ||
unlikely(f2fs_cp_error(sbi)))
goto next;
sum = page_address(sum_page);
f2fs_bug_on(sbi, type != GET_SUM_TYPE((&sum->footer)));
/*
* this is to avoid deadlock:
* - lock_page(sum_page) - f2fs_replace_block
* - check_valid_map() - down_write(sentry_lock)
* - down_read(sentry_lock) - change_curseg()
* - lock_page(sum_page)
*/
if (type == SUM_TYPE_NODE)
gc_node_segment(sbi, sum->entries, segno, gc_type);
else
gc_data_segment(sbi, sum->entries, gc_list, segno,
gc_type);
stat_inc_seg_count(sbi, type, gc_type);
if (gc_type == FG_GC &&
get_valid_blocks(sbi, segno, false) == 0)
seg_freed++;
next:
f2fs_put_page(sum_page, 0);
}
if (gc_type == FG_GC)
f2fs_submit_merged_write(sbi,
(type == SUM_TYPE_NODE) ? NODE : DATA);
blk_finish_plug(&plug);
stat_inc_call_count(sbi->stat_info);
return seg_freed;
}
int f2fs_gc(struct f2fs_sb_info *sbi, bool sync,
bool background, unsigned int segno)